The most recent annual survey by the National Institute on Drug Abuse (NIDA) shows that the use of regular cigarettes by middle and high school students continues to trend downward. However, for the first time the NIDA survey includes questions about the use of e-cigarettes, and the results are startling. Already, the use of e-cigarettes among middle- and high-schoolers exceeds the use of regular cigarettes. Among eighth-graders, 8.7% have used e-cigarettes but only have used regular cigarettes. And by the 12th grade, 17% have used e-cigarettes and 13.7% have used regular cigarettes.
This is the first time the annual NIDA survey has included questions about e-cigarettes, so there's no way to determine how quickly e-cigarette use is rising among young people. Within the next year or so (once we have more data) the trend will become clearer.
Health officials and e-cigarette manufacturers couldn't be farther apart on their goals for e-cigarettes. Health officials would like to see e-cigarettes used only as a useful tool to help current smokers quit smoking. Their chief concern is that e-cigarettes may encourage a whole new generation of young people to smoke who might otherwise never have smoked. E-cigarette manufacturers, on other hand, stand to reap huge profits from the much larger youth market. My guess is that the e-cigarette manufacturers are secretly pleased by the latest statistics, though I don't expect them to say so.
Although e-cigarettes are considered to be relatively safe, they do contain nicotine, an addictive drug. It will be interesting to see how (or if) the federal government or the states choose to regulate e-cigarette use in the future.
Monday, December 22, 2014
Wednesday, December 17, 2014
The FDA Approves a New Version of Gardasil
The FDA has approved a "new and improved" version of Gardasil, the controversial vaccine against Human Papillomavirus (HPV), the group of viruses that cause cervical cancer. The original Gardasil was effective against four types of HPV. The new version, called "Gardasil 9", is effective against those four types of HPV plus five more, for a total of nine.
Gardasil 9 is approved for use in both males and females. In males it is approved for prevention of anal cancer, and coincidentally it would also be effective in preventing the spread of HPV to females. Like the original Gardasil, Gardasil 9 is administered as a series of three shots.
Gardasil remains a controversial vaccine. Some people think that vaccinating young girls against a sexually transmitted virus will lead to promiscuity, even though the available suggests otherwise (see this Blog Oct. 21, 2012). There's also a rumor going around that Gardasil has caused the deaths of dozens of young women; that's not true, either, according to a leading rumor-checking site. The CDC, which collects reports of "adverse effects" on all drugs, continues to stress that Gardasil is safe.
Gardasil 9 is approved for use in both males and females. In males it is approved for prevention of anal cancer, and coincidentally it would also be effective in preventing the spread of HPV to females. Like the original Gardasil, Gardasil 9 is administered as a series of three shots.
Gardasil remains a controversial vaccine. Some people think that vaccinating young girls against a sexually transmitted virus will lead to promiscuity, even though the available suggests otherwise (see this Blog Oct. 21, 2012). There's also a rumor going around that Gardasil has caused the deaths of dozens of young women; that's not true, either, according to a leading rumor-checking site. The CDC, which collects reports of "adverse effects" on all drugs, continues to stress that Gardasil is safe.
Sunday, December 14, 2014
Does Platelet-Rich Plasma Therapy Work?
Great in theory, unproven in practice. It's been at least six years since Platelet-Rich Plasma Therapy (PRPT) was first proposed as a technique for speeding recovery from joint and connective tissue injuries, and we still don't know if it works!
In PRPT, a patient's own plasma is enriched in platelets by removal of blood cells and most of the water (see this blog Feb. 18, 2009). The remaining platelet-rich plasma is injected directly into the patient's injured joint or connective tissue. In theory, proteins and growth factors released by the platelets should speed the healing process. But do they?
The problem is that despite numerous clinical studies, the results are still inconsistent, according to an NPR article. I reported on two such studies back in 2010 (see "Platelet-Rich Plasma Therapy Revisited"). Part of the problem is that in most studies the number of patients is relatively small (fewer than a hundred patients, rather than a thousand or more) and the techniques used and types of injuries treated vary. And since it's not yet proven to work, insurance companies don't pay for the procedure, meaning that the patient pays the total cost of roughly $600 to $1,500.
We should have known by now whether the technique works. We're still waiting....
In PRPT, a patient's own plasma is enriched in platelets by removal of blood cells and most of the water (see this blog Feb. 18, 2009). The remaining platelet-rich plasma is injected directly into the patient's injured joint or connective tissue. In theory, proteins and growth factors released by the platelets should speed the healing process. But do they?
The problem is that despite numerous clinical studies, the results are still inconsistent, according to an NPR article. I reported on two such studies back in 2010 (see "Platelet-Rich Plasma Therapy Revisited"). Part of the problem is that in most studies the number of patients is relatively small (fewer than a hundred patients, rather than a thousand or more) and the techniques used and types of injuries treated vary. And since it's not yet proven to work, insurance companies don't pay for the procedure, meaning that the patient pays the total cost of roughly $600 to $1,500.
We should have known by now whether the technique works. We're still waiting....
Friday, December 12, 2014
An Outbreak of Mumps in the National Hockey League
About a dozen National Hockey League players have come down with mumps in the past two months, according to CBS Sports. The outbreak seems to have started with the Anaheim Ducks (four players), but it soon spread to other teams, including the Minnesota Wild (five players), the New York Rangers (one player), and the New Jersey Devils (two players). A dozen cases of mumps on teams with a total player count of only a couple hundred players is a lot, considering that there have been only about a thousand cases of mumps in the entire country this year, according to the CDC.
But it makes sense, actually. Mumps is spread by contact with infected saliva or mucus, usually via coughing or sneezing. The close-knit conditions in a hockey locker room and frequent intense physical contact on the ice would be ideal conditions for the disease to spread. An infected person can infect others for several days before they exhibit the typical symptoms, of tiredness, fever, headaches, muscle pain, and glandular swelling - plenty of time for a hockey player to inadvertently pass his infection on to a player from another team. The Anaheim Ducks played the Minnesota Wild in mid-October. In addition, some infected persons never show the typical symptoms at all. Yet they can still infect others, making it hard to trace and eradicate an outbreak.
Although the NHL isn't too worried (mumps is not a particularly life-threatening disease), the outbreak has been disruptive in that players have had to miss games while they are sick. The league is warning teams and players about the outbreak in a hope of stemming the disease's spread. Most of the players had already been vaccinated against mumps (mumps is primarily disease of childhood, and vaccination against mumps is part of the normal vaccination regimen for children), but health officials report that the vaccine is not 100% effective; it's more like 78%. An additional vaccination can boost effectiveness to 88%, and some teams are offering the second vaccination as a precaution.
But it makes sense, actually. Mumps is spread by contact with infected saliva or mucus, usually via coughing or sneezing. The close-knit conditions in a hockey locker room and frequent intense physical contact on the ice would be ideal conditions for the disease to spread. An infected person can infect others for several days before they exhibit the typical symptoms, of tiredness, fever, headaches, muscle pain, and glandular swelling - plenty of time for a hockey player to inadvertently pass his infection on to a player from another team. The Anaheim Ducks played the Minnesota Wild in mid-October. In addition, some infected persons never show the typical symptoms at all. Yet they can still infect others, making it hard to trace and eradicate an outbreak.
Although the NHL isn't too worried (mumps is not a particularly life-threatening disease), the outbreak has been disruptive in that players have had to miss games while they are sick. The league is warning teams and players about the outbreak in a hope of stemming the disease's spread. Most of the players had already been vaccinated against mumps (mumps is primarily disease of childhood, and vaccination against mumps is part of the normal vaccination regimen for children), but health officials report that the vaccine is not 100% effective; it's more like 78%. An additional vaccination can boost effectiveness to 88%, and some teams are offering the second vaccination as a precaution.
Sunday, November 30, 2014
The Declining Availability of Fresh Water
The natural fresh water cycle (the cycling of water from oceans to the atmosphere, becoming precipitation in the form of rain and snow) is the source of the fresh water in the Earth's lakes, streams, and underground aquifers. The water cycle is timeless and largely unaffected by man, except for the probable influence of global warming. But the supply of clean fresh water available to humans (where humans choose to locate) is slowly but surely declining.
Many western U.S. cities rely primarily on water derived from the winter snowpack in nearby mountain ranges. The cities are growing and demand for water is up. To make matters worse, the winter snowpack has been declining in recent years. Some of the snowpack's decline may be due to global warming, but it may also be partly due to normal decades-long cyclic fluctuations in the water cycle. Centuries-old glaciers have been receding; some have disappeared entirely. If the current 30-year trend continues, Montana's Glacier National Park in may not have a single glacier by 2030. This does not bode well for Western lakes and streams.
Some human populations rely heavily on ancient underground aquifers for water to irrigate thirsty crops. China, India, and the U.S. plains States all rely heavily on aquifers that are not being replenished at the rates at which they are being used. Wells in some areas are going dry, leading to a loss of agricultural productivity.
Pollution of freshwater is a constant concern. Industries that use a lot of water or that run the risk of polluting rivers and streams, such as mining for coal, copper, and gold, face increasing government regulation or outright opposition from environmental groups. The world's largest gold mining company, Barrick Gold, shut down a major investment in a massive mine in Chile due in part to costs related to the risk of polluting nearby rivers and streams.
These are not problems that are going to go away quickly. Humans will have to adapt. We'll need to reduce water use in our homes, recycle water wherever possible, locate our human populations nearer to abundant supplies of fresh water, develop agricultural crops that require less water, irrigate crops more efficiently, and improve industrial techniques that require water. Some of these actions are already being taken. As they must, if we are to prosper in the long run.
Many western U.S. cities rely primarily on water derived from the winter snowpack in nearby mountain ranges. The cities are growing and demand for water is up. To make matters worse, the winter snowpack has been declining in recent years. Some of the snowpack's decline may be due to global warming, but it may also be partly due to normal decades-long cyclic fluctuations in the water cycle. Centuries-old glaciers have been receding; some have disappeared entirely. If the current 30-year trend continues, Montana's Glacier National Park in may not have a single glacier by 2030. This does not bode well for Western lakes and streams.
Some human populations rely heavily on ancient underground aquifers for water to irrigate thirsty crops. China, India, and the U.S. plains States all rely heavily on aquifers that are not being replenished at the rates at which they are being used. Wells in some areas are going dry, leading to a loss of agricultural productivity.
Pollution of freshwater is a constant concern. Industries that use a lot of water or that run the risk of polluting rivers and streams, such as mining for coal, copper, and gold, face increasing government regulation or outright opposition from environmental groups. The world's largest gold mining company, Barrick Gold, shut down a major investment in a massive mine in Chile due in part to costs related to the risk of polluting nearby rivers and streams.
These are not problems that are going to go away quickly. Humans will have to adapt. We'll need to reduce water use in our homes, recycle water wherever possible, locate our human populations nearer to abundant supplies of fresh water, develop agricultural crops that require less water, irrigate crops more efficiently, and improve industrial techniques that require water. Some of these actions are already being taken. As they must, if we are to prosper in the long run.
Wednesday, November 26, 2014
The Benefits of Genetically Modified Crops
Opponents of genetically modified (GM) crops are quick to point out the potential risks involved in planting GM crops and in eating foods with GM ingredients. Some of the risks, such as the potential for encouraging the emergence of "superweeds" that are resistant to the herbicides used on GM crops, and the inadvertent cross-pollination of normal crops by GM crops in nearby fields, are real. Others, such as the potential for causing future unspecified human health problems, are as yet undocumented.
Are there any known benefits of GM crops, other than for the farmer? A recent meta-analysis published in PLOS one concludes that indeed there are. The authors of the analysis reviewed all of the previous reports of the economic and agricultural impacts of three GM crops (soybeans, maize, and cotton) published in English between 1995 and early 2014; 147 studies in all. They found that in addition to improving farmer's profits by 68%, the use of GM crops increased crop yields by 22% and decreased chemical pesticide use by 37%.
Increased profits for farmers is not a bad thing, for it means they pay more taxes and have more money to spend (stimulating the economy). Increased crop yields allows more people to be fed per acre of agricultural land; something to think about as Earth's human population continues to rise even as the amount of arable land remains constant. Finally, reducing chemical pesticide use by more than a third can only be good for the environment.
I'm not saying that GM crops are perfect. I'm well aware that there are risks, some of which may still be unknown. I'm just saying that in any dialogue about whether we should allow GM crops, we should consider both the risks and the benefits, and not just focus on one or the other. Do not be fooled into thinking that there is only one side (yours?) in this debate.
Are there any known benefits of GM crops, other than for the farmer? A recent meta-analysis published in PLOS one concludes that indeed there are. The authors of the analysis reviewed all of the previous reports of the economic and agricultural impacts of three GM crops (soybeans, maize, and cotton) published in English between 1995 and early 2014; 147 studies in all. They found that in addition to improving farmer's profits by 68%, the use of GM crops increased crop yields by 22% and decreased chemical pesticide use by 37%.
Increased profits for farmers is not a bad thing, for it means they pay more taxes and have more money to spend (stimulating the economy). Increased crop yields allows more people to be fed per acre of agricultural land; something to think about as Earth's human population continues to rise even as the amount of arable land remains constant. Finally, reducing chemical pesticide use by more than a third can only be good for the environment.
I'm not saying that GM crops are perfect. I'm well aware that there are risks, some of which may still be unknown. I'm just saying that in any dialogue about whether we should allow GM crops, we should consider both the risks and the benefits, and not just focus on one or the other. Do not be fooled into thinking that there is only one side (yours?) in this debate.
Saturday, November 8, 2014
Increasing Incidence of Colorectal Cancers in Young People
A review of the nearly 400,000 reported cases of cancers of the colon and rectum between 1975 and 2010 reveals some interesting trends. Overall, the incidence of colorectal cancers declined by just under 1% per year, due to a steady decline in persons 50 years of age or older. However, the incidence of colorectal cancers rose in the youngest age group; persons aged 20-34. Based on current trends, rates of colorectal cancers in this age group will nearly double by 2030.
The current study provides no information regarding the cause of the upward trend. But this is how science works; based on an observation, (a rising rate of colorectal cancers in young people) a hypothesis must be formed and further study undertaken to test it.
Perhaps by 2030 we'll know why colorectal cancers are increasing in young people, and also know what to do about it. The optimist in me hopes so.
The current study provides no information regarding the cause of the upward trend. But this is how science works; based on an observation, (a rising rate of colorectal cancers in young people) a hypothesis must be formed and further study undertaken to test it.
Perhaps by 2030 we'll know why colorectal cancers are increasing in young people, and also know what to do about it. The optimist in me hopes so.
Thursday, November 6, 2014
The FDA approves a Vaccine for a Rare Meningitis
Last fall an outbreak of a rare form of meningitis called serotype B occurred on the campus of Princeton University. Months later a similar outbreak occurred at the University of California Santa Barbara (UCSB). Although a vaccine against serotype B meningitis was available in Canada and Europe, it had not yet been approved in the U.S. Nevertheless, because of the dangerous nature of meningitis and the ease with which the disease might spread on college campuses (it's spread by close contact such as kissing or sharing eating utensils) the FDA granted emergency approval of the vaccine, just for students of Princeton and UCSB. The vaccine worked, the outbreaks subsided, and a greater crisis was averted.
Recognizing that the normal approval process for a vaccine or drug can take years, the FDA has developed a fast-track approval process for vaccines and drugs that meet certain criteria. Two competing vaccines against meningitis serotype B were fast-tracked under this program, and last week the FDA approved the first one, Pfizer's Trumenba.
And that's interesting, because the vaccine approved on an emergency basis for the students of Princeton and UCSB was the other vaccine, called Bexero, made by Novartis. We hope it's just that Pfizer just did a better (and faster) job of satisfying the FDA of its product's safety and effectiveness.
Now that a vaccine for meningitis serotype B is available, should it become part of the standard vaccination schedule for all children? That hasn't been decided yet, but the decision rests with the Centers for Disease Control and Prevention (CDC), not the FDA.
Recognizing that the normal approval process for a vaccine or drug can take years, the FDA has developed a fast-track approval process for vaccines and drugs that meet certain criteria. Two competing vaccines against meningitis serotype B were fast-tracked under this program, and last week the FDA approved the first one, Pfizer's Trumenba.
And that's interesting, because the vaccine approved on an emergency basis for the students of Princeton and UCSB was the other vaccine, called Bexero, made by Novartis. We hope it's just that Pfizer just did a better (and faster) job of satisfying the FDA of its product's safety and effectiveness.
Now that a vaccine for meningitis serotype B is available, should it become part of the standard vaccination schedule for all children? That hasn't been decided yet, but the decision rests with the Centers for Disease Control and Prevention (CDC), not the FDA.
Saturday, November 1, 2014
New Uses for Wearable Skin Patches
Previously I talked about how wearable skin patches not much bigger than a Band-Aid that could be used to deliver drugs or vaccines (see "A Skin Patch to Deliver the Flu Vaccine"). Wearable skin patches are being developed for other uses as well, including monitoring a patient's vital signs and diagnosing specific diseases.
Swedish researchers are developing a wearable skin patch called the Bio-patch, with embedded wireless micro-sensors and a small battery. The Bio-patch could be used to monitor a patient's vital signs and send them wirelessly to a smartphone or to the patient's doctor. The Bio-patch would permit 24-hour monitoring of a patient, enabling a physician to know exactly when a patient's condition has changed. Sensors have been developed to monitor body temperature and the electrical activity of the heart (an electrocardiogram; ECG) and brain (an electroencephalogram; EEG).
An Australian group is developing a wearable skin patch with tiny micro-needles that penetrate the outer layer of the skin and sample the intradermal fluid. The tiny micro-needles are coated with antibodies that detect the presence of antigens from the malaria parasite, Plasmodium falciparum. The device can detect malaria in a patient without the need for a blood sample and blood analysis. So far the device has only been tested on mice, and only to detect malaria. But in theory, it should also work in humans and it could conceivably be used to test for nearly any disease in which disease antibodies are present in interstitial fluid.
It's a pretty good bet that within the next decate you'll see some of these products come to market.
Swedish researchers are developing a wearable skin patch called the Bio-patch, with embedded wireless micro-sensors and a small battery. The Bio-patch could be used to monitor a patient's vital signs and send them wirelessly to a smartphone or to the patient's doctor. The Bio-patch would permit 24-hour monitoring of a patient, enabling a physician to know exactly when a patient's condition has changed. Sensors have been developed to monitor body temperature and the electrical activity of the heart (an electrocardiogram; ECG) and brain (an electroencephalogram; EEG).
An Australian group is developing a wearable skin patch with tiny micro-needles that penetrate the outer layer of the skin and sample the intradermal fluid. The tiny micro-needles are coated with antibodies that detect the presence of antigens from the malaria parasite, Plasmodium falciparum. The device can detect malaria in a patient without the need for a blood sample and blood analysis. So far the device has only been tested on mice, and only to detect malaria. But in theory, it should also work in humans and it could conceivably be used to test for nearly any disease in which disease antibodies are present in interstitial fluid.
It's a pretty good bet that within the next decate you'll see some of these products come to market.
Monday, October 27, 2014
Recalled Dietary Supplements Return to the Shelves
Unlike pharmaceutical drugs, dietary supplements do not have to be proven safe and effective before they can be sold. All the FDA can do is to force specific products to be pulled from store shelves (recalled) after it receives complaints about the product's safety.
A study published in JAMA shows how ineffective the FDA's recall power really is. The authors of the study examined 27 dietary supplement products that had been recalled by the FDA. Some of the products were recalled for containing anabolic steroids or prescription drugs such as Viagra and Prozac. Several weight-loss products contained an amphetamine-like drug not approved in the U.S. The authors found that within an average of three years after recall, approximately 2/3 of the products were being sold again - under the same name and with the same ingredients. Even the manufacturers and distributors were the same! Most of the manufacturers are U.S.-based.
Why can't the FDA put a stop to this? In part, their hands are tied because dietary supplement manufacturers have the right to sell their products without any proof that they are safe and effective. Tainted products are only identified after they have hit store shelves and after complaints are received. And even then, recall can be difficult because many of these products are sold over the internet from unknown physical addresses.
Until the dietary supplements regulatory environment changes and the FDA is given more power to punish unscrupulous companies, it remains "buyer beware" when it comes to dietary supplements. Unfortunately for us, the authors did not name the manufacturers, distributors, or products in their study. That's a shame.
A study published in JAMA shows how ineffective the FDA's recall power really is. The authors of the study examined 27 dietary supplement products that had been recalled by the FDA. Some of the products were recalled for containing anabolic steroids or prescription drugs such as Viagra and Prozac. Several weight-loss products contained an amphetamine-like drug not approved in the U.S. The authors found that within an average of three years after recall, approximately 2/3 of the products were being sold again - under the same name and with the same ingredients. Even the manufacturers and distributors were the same! Most of the manufacturers are U.S.-based.
Why can't the FDA put a stop to this? In part, their hands are tied because dietary supplement manufacturers have the right to sell their products without any proof that they are safe and effective. Tainted products are only identified after they have hit store shelves and after complaints are received. And even then, recall can be difficult because many of these products are sold over the internet from unknown physical addresses.
Until the dietary supplements regulatory environment changes and the FDA is given more power to punish unscrupulous companies, it remains "buyer beware" when it comes to dietary supplements. Unfortunately for us, the authors did not name the manufacturers, distributors, or products in their study. That's a shame.
Wednesday, October 22, 2014
Canada Opens First Carbon Capture Power Plant
Canada recently completed the first commercial-scale coal-fired power plant designed to capture and sequester greenhouse gases. The plant will capture around 90% of the CO2 that the plant generates - about a million tons a year. The CO2 will either be sold to a nearby oil company to enhance oil production or buried deep underground.
The new plant, called Boundary Dam, demonstrates that it is possible to burn coal without damaging the environment in the process. But don't expect the more than 1,000 coal-fired power plants in the planning stages worldwide (most of them in China) to adapt the technology any time soon. The technology is economically feasible at the Boundary Dam plant because the plant received substantial subsidies from the Canadian government and because the plant is located in an area in which the CO2 could be sold to oil producers, who use the CO2 to enhance oil production.
And there's the irony. Some of the CO2 not released into the atmosphere by the coal-fired power plant will be used to enhance the production of oil, which of course is also a fossil fuel that releases CO2 when it is burned. I suppose there's still a net reduction in CO2 released into the atmosphere, but it's not the full million tons a year.
The new plant, called Boundary Dam, demonstrates that it is possible to burn coal without damaging the environment in the process. But don't expect the more than 1,000 coal-fired power plants in the planning stages worldwide (most of them in China) to adapt the technology any time soon. The technology is economically feasible at the Boundary Dam plant because the plant received substantial subsidies from the Canadian government and because the plant is located in an area in which the CO2 could be sold to oil producers, who use the CO2 to enhance oil production.
And there's the irony. Some of the CO2 not released into the atmosphere by the coal-fired power plant will be used to enhance the production of oil, which of course is also a fossil fuel that releases CO2 when it is burned. I suppose there's still a net reduction in CO2 released into the atmosphere, but it's not the full million tons a year.
Sunday, October 19, 2014
Another Artificial Sweetener
There's a new artificial sweetener about to hit the market that's more than 30 times sweeter than saccharine (Sweet-n-Low), aspartame (Nutrasweet and Equal), or sucralose (Splenda). The new sweetener, called advantame (it does not have a catchy brand name yet), is made by Ajinomoto, a Japanese company.
Although it's entering a crowded and competitive field, Advantame will probably find a niche in the marketplace because it doesn't break down as readily as other sweeteners under heat. That means that it'll probably become the artificial sweetener of choice in baked goods.
The FDA approved the new sweetener in May. It's not clear how long it'll be before it's found in the products you buy.
Although it's entering a crowded and competitive field, Advantame will probably find a niche in the marketplace because it doesn't break down as readily as other sweeteners under heat. That means that it'll probably become the artificial sweetener of choice in baked goods.
The FDA approved the new sweetener in May. It's not clear how long it'll be before it's found in the products you buy.
Topics:
diets and dieting,
digestion and nutrition
Sunday, October 12, 2014
Antibiotic Use in Farm Animals is Still Increasing
According to an FDA report issued recently, the amount of antibiotics sold for use in food-producing animals increased 16% between 2009 and 2012. The use of cephalosporins, a class of antibiotics widely used in humans, increased by a whopping 37% over the same time period. Health officials, of course, are worried that the overuse of antibiotics leads to the rise of antibiotic-resistant strains of bacteria, threatening human health.
The FDA issued new guidelines in 2013 that are meant to restrict the use of antibiotics in food-producing animals, but it's too early to tell whether they will work. Basically, the new rules prohibit the use of antibiotics in healthy animals for the sole purpose of increasing weight gain. Instead, antibiotics may used only in sick animals to treat disease, and only when prescribed by a veterinarian. The new rules will take effect over the next three years.
Ranchers know that antibiotics cause even healthy animals to gain weight. That means that ranchers have a big financial incentive to use antibiotics indiscriminately, and veterinarians who work in farm communities will have a financial incentive to write the prescriptions. The FDA is trying to (gently) nudge the livestock production industry toward practices that are better for society as a whole, but not for the food-producing industry. So you think the new rules will reduce antibiotic use in food-producing animals very much? If they don't, what would you suggest we do next?
The FDA issued new guidelines in 2013 that are meant to restrict the use of antibiotics in food-producing animals, but it's too early to tell whether they will work. Basically, the new rules prohibit the use of antibiotics in healthy animals for the sole purpose of increasing weight gain. Instead, antibiotics may used only in sick animals to treat disease, and only when prescribed by a veterinarian. The new rules will take effect over the next three years.
Ranchers know that antibiotics cause even healthy animals to gain weight. That means that ranchers have a big financial incentive to use antibiotics indiscriminately, and veterinarians who work in farm communities will have a financial incentive to write the prescriptions. The FDA is trying to (gently) nudge the livestock production industry toward practices that are better for society as a whole, but not for the food-producing industry. So you think the new rules will reduce antibiotic use in food-producing animals very much? If they don't, what would you suggest we do next?
Topics:
infectious disease,
science and society
Wednesday, October 8, 2014
FDA Approves Home Test for Colon Cancer
The FDA has approved a new home test for colon cancer. The new test, called "Cologuard", tests not only for hidden blood in the stool, but also for changes to DNA that may signal the presence of colon cancer.
Current recommendations by the U.S. Preventive Services Task Force for screening for colon cancer are that persons aged 50-75 should have an occult blood test every year and a colonoscopy every 10 years. Whether the Task Force will include Cologuard as an option in future recommendations is unknown. Nor is it clear yet whether Medicare or most insurance companies will pay for the test. That's critical to its acceptance because Cologuard costs nearly $600; much more than the standard occult blood test.
With any test, it's important to consider how accurate the test is. Cologuard appears to be better than the occult blood test at detecting cancers when they are present (92% of cancers detected, versus 74% for the occult blood test). However, Cologuard also has a higher "false positive" rate (reporting that cancer may be present when in fact it is not) of 13% versus 5% for the occult blood test. A positive result with Cologuard should be followed up with a colonoscopy, just to be sure.
Cologuard isn't perfect. But if it is used by people who refuse to go to the doctor for a blood test or especially for a colonoscopy, then it will serve a purpose.
Current recommendations by the U.S. Preventive Services Task Force for screening for colon cancer are that persons aged 50-75 should have an occult blood test every year and a colonoscopy every 10 years. Whether the Task Force will include Cologuard as an option in future recommendations is unknown. Nor is it clear yet whether Medicare or most insurance companies will pay for the test. That's critical to its acceptance because Cologuard costs nearly $600; much more than the standard occult blood test.
With any test, it's important to consider how accurate the test is. Cologuard appears to be better than the occult blood test at detecting cancers when they are present (92% of cancers detected, versus 74% for the occult blood test). However, Cologuard also has a higher "false positive" rate (reporting that cancer may be present when in fact it is not) of 13% versus 5% for the occult blood test. A positive result with Cologuard should be followed up with a colonoscopy, just to be sure.
Cologuard isn't perfect. But if it is used by people who refuse to go to the doctor for a blood test or especially for a colonoscopy, then it will serve a purpose.
Wednesday, October 1, 2014
First U.S. Ebola Case
A man who traveled to the U.S. from Liberia via Europe is now the first person to be diagnosed with Ebola while within the U.S. At least one of the major news services is giving this one "event" continuous coverage all day, which of course raises our fear level; it makes it sound like this one case of Ebola could lead to an epidemic in this country.
Nothing could be further from the truth. According to the CDC, Ebola is transmitted primarily in bodily fluids such as urine, saliva, or blood. In addition, Ebola patients can only infect others when they are actually sick - not before and not after. The patient in question didn't feel sick until several days after he arrived in the U.S. And four days after he began to feel sick, he was isolated in a hospital prepared to deal with diseases such as this. That means, for example, that he did not infect anyone on his incoming transatlantic flight, and he's probably not going to infect anyone else after the time he was hospitalized. At most, he could have infected some of the people with whom he had close contact in the four days during which he felt sick before he was hospitalized.
Public health officials certainly have their hands full finding all the people with whom the Ebola patient had direct contact, and monitoring them for 21 days. Surveillance is tedious, but it works. So relax; at least one expert doesn't think an Ebola epidemic is likely in this country. Ebola is just not transmitted easily enough.
Sensationalism sells. But the news services should dial back their continuous coverage of what is probably a non-event.
Nothing could be further from the truth. According to the CDC, Ebola is transmitted primarily in bodily fluids such as urine, saliva, or blood. In addition, Ebola patients can only infect others when they are actually sick - not before and not after. The patient in question didn't feel sick until several days after he arrived in the U.S. And four days after he began to feel sick, he was isolated in a hospital prepared to deal with diseases such as this. That means, for example, that he did not infect anyone on his incoming transatlantic flight, and he's probably not going to infect anyone else after the time he was hospitalized. At most, he could have infected some of the people with whom he had close contact in the four days during which he felt sick before he was hospitalized.
Public health officials certainly have their hands full finding all the people with whom the Ebola patient had direct contact, and monitoring them for 21 days. Surveillance is tedious, but it works. So relax; at least one expert doesn't think an Ebola epidemic is likely in this country. Ebola is just not transmitted easily enough.
Sensationalism sells. But the news services should dial back their continuous coverage of what is probably a non-event.
Monday, September 29, 2014
Ebola Update
The U.S. Centers for Disease Control and Prevention (CDC) reports that as of last week, over 6,000 people have been infected with the Ebola virus and more than 2,900 have died. Although Ebola infections have been identified in five countries, to date the epidemic is confined primarily to just three; Guinea, Sierra Leone, and Liberia. Senegal has had just one case (a man who traveled from Guinea) and Nigeria, with 8 deaths, hasn't had a new case in almost three weeks.
The death rate among infected persons remains close to 50%. This is a virus that kills its victims rather quickly and is difficult to treat. Fortunately, person-to-person transmission requires close contact in the form of exchange of fluids. But that means that the people at highest risk of becoming infected are health care workers. The World Health Organization reports that more than 120 health care workers have died since the outbreak began. The lack of proper facilities and equipment to effectively isolate patients and protect health care workers is a factor.
Most airlines have cancelled commercial flights to the three countries at the center of the outbreak. Travel between and within the three countries has been restricted as well. A side effect of travel bans is that the flow of health care workers and medical equipment/supplies to affected areas is made more difficult.
This epidemic is not over yet. It may not even have peaked.
The death rate among infected persons remains close to 50%. This is a virus that kills its victims rather quickly and is difficult to treat. Fortunately, person-to-person transmission requires close contact in the form of exchange of fluids. But that means that the people at highest risk of becoming infected are health care workers. The World Health Organization reports that more than 120 health care workers have died since the outbreak began. The lack of proper facilities and equipment to effectively isolate patients and protect health care workers is a factor.
Most airlines have cancelled commercial flights to the three countries at the center of the outbreak. Travel between and within the three countries has been restricted as well. A side effect of travel bans is that the flow of health care workers and medical equipment/supplies to affected areas is made more difficult.
This epidemic is not over yet. It may not even have peaked.
Tuesday, September 23, 2014
A National Strategy to Combat Antibiotic Resistance
In a 37-page document released this month, the Obama administration proposed a national strategy for combating the growing problem of antibiotic-resistant bacteria. It's about time. From an evolutionary point of view, the misuse and overuse of antibiotics in health care and food production will inevitably lead to the emergence of antibiotic-resistant strains of bacteria, because bacteria can adapt and evolve so quickly. We've been talking about this problem for a while now on this blog.
An interagency task force led by the secretaries of health and human services, agriculture, and defense has been tasked with developing a specific action plan within six months. The task force will then coordinate with government agencies to see that the required actions are taken. Finally, the task force will report regularly to the President on progress made toward specific goals outlined in the document.
The goals, objectives, and achievement targets listed in the document are clear, appropriate, and likely to be effective if they could actually be accomplished. It will be interesting to see, say five years from now, if any real progress has been made, or whether this is just a good plan without adequate follow-through. For example, one of the stated objectives; to "eliminate the use of medically important antibiotics for growth promotion in animals..." is likely to meet with stiff resistance from farmers.
I, for one, applaud the effort and hope for real progress.
For more on this subject, go to a previous blog post titled "First Official Report on Deaths from Antibiotic-resistant Bacteria."
An interagency task force led by the secretaries of health and human services, agriculture, and defense has been tasked with developing a specific action plan within six months. The task force will then coordinate with government agencies to see that the required actions are taken. Finally, the task force will report regularly to the President on progress made toward specific goals outlined in the document.
The goals, objectives, and achievement targets listed in the document are clear, appropriate, and likely to be effective if they could actually be accomplished. It will be interesting to see, say five years from now, if any real progress has been made, or whether this is just a good plan without adequate follow-through. For example, one of the stated objectives; to "eliminate the use of medically important antibiotics for growth promotion in animals..." is likely to meet with stiff resistance from farmers.
I, for one, applaud the effort and hope for real progress.
For more on this subject, go to a previous blog post titled "First Official Report on Deaths from Antibiotic-resistant Bacteria."
Thursday, September 18, 2014
E-cigarettes Help Smokers Quit
Say what you want about e-cigarettes, but the fact is that they work better than other methods at helping smokers quit on their own. According to a study just published in Addiction, smokers who choose e-cigarettes are more likely report that they have quit smoking than smokers who try to quit based on willpower alone and smokers who use nicotine replacement therapy products such as the nicotine patch.
And there’s the conundrum for regulators. On the one hand, they need to support regulations that keep e-cigarettes widely available, because if current smokers choose to use them and thereby ultimately quit smoking cigarettes, lives will be saved. On the other hand, they don’t want e-cigarettes to become too popular, especially among the young or people who have never smoked. The end result could be a lot of people who become nicotine addicts without ever having smoked cigarettes. And while e-cigarettes are thought to be much safer than cigarettes and probably don’t increase the risk of cancer, who wants a whole new generation of nicotine addicts? And how safe are e-cigarettes, anyway? It may be years before we know.
I expect regulators (the FDA) to focus on how e-cigarettes are marketed, and to develop regulations that try to prevent e-cigarettes from becoming too popular with young non-smokers. But of course, that’s precisely the market that manufacturers would like to reach, because it's a much larger market than just current smokers who seriously wish to quit. Regulators versus manufacturers - it’s the battle over the marketing of cigarettes all over again.
And there’s the conundrum for regulators. On the one hand, they need to support regulations that keep e-cigarettes widely available, because if current smokers choose to use them and thereby ultimately quit smoking cigarettes, lives will be saved. On the other hand, they don’t want e-cigarettes to become too popular, especially among the young or people who have never smoked. The end result could be a lot of people who become nicotine addicts without ever having smoked cigarettes. And while e-cigarettes are thought to be much safer than cigarettes and probably don’t increase the risk of cancer, who wants a whole new generation of nicotine addicts? And how safe are e-cigarettes, anyway? It may be years before we know.
I expect regulators (the FDA) to focus on how e-cigarettes are marketed, and to develop regulations that try to prevent e-cigarettes from becoming too popular with young non-smokers. But of course, that’s precisely the market that manufacturers would like to reach, because it's a much larger market than just current smokers who seriously wish to quit. Regulators versus manufacturers - it’s the battle over the marketing of cigarettes all over again.
Monday, September 15, 2014
Alcoholic Beverages Made From Non-GMO Grains
A leading manufacturer of distilled alcohol products has announced that it will begin manufacturing a line of neutral grain spirits from non-GMO grain, in addition to its traditional products made from genetically modified grains. The company says that it’s a market-driven decision, based on consumer perceptions that GMO foods may pose “unknown safety risks”.
If you oppose the development and planting of GMO plants because you think they might be bad for the environment, then you can rightfully cheer this decision. But if you think that drinking a distilled alcohol product made from GMO grains might be more harmful to drink than alcohol made from non-GMO grain, you’re misguided. Although the grain from GMO plants would contain a foreign protein or two, proteins are destroyed by the heat of the distillation process. And even if proteins weren’t destroyed by heat, they don’t vaporize and then condense again, so they wouldn’t end up in the final distillation product anyway. The final distillation product is essentially just alcohol and water.
The bottom line is that there aren’t any GMO proteins in distilled alcohol, even when it’s made from GMO grain. By making distilled alcohol products from non-GMO grain, the manufacturer is responding to the perception of a health risk by its potential customers, not the actual reality.
If you oppose the development and planting of GMO plants because you think they might be bad for the environment, then you can rightfully cheer this decision. But if you think that drinking a distilled alcohol product made from GMO grains might be more harmful to drink than alcohol made from non-GMO grain, you’re misguided. Although the grain from GMO plants would contain a foreign protein or two, proteins are destroyed by the heat of the distillation process. And even if proteins weren’t destroyed by heat, they don’t vaporize and then condense again, so they wouldn’t end up in the final distillation product anyway. The final distillation product is essentially just alcohol and water.
The bottom line is that there aren’t any GMO proteins in distilled alcohol, even when it’s made from GMO grain. By making distilled alcohol products from non-GMO grain, the manufacturer is responding to the perception of a health risk by its potential customers, not the actual reality.
Friday, September 5, 2014
The Connection Between HIV and Multiple Sclerosis
It began as an observation in 2011; an Australian doctor who treats patients with HIV noticed that he had never had an HIV patient who went on to develop multiple sclerosis (MS). A literature search essentially confirmed his observations - there was just one known HIV patient who developed MS, and that patient's symptoms went away after undergoing the usual treatment regimen for HIV. So, he thought; is HIV infection (or its treatment regimen) somehow protective against MS?
To find out, the doctor and his coworkers needed access to the records of a large number of patients, because the number of people in a population who are HIV-positive is not all that large, and the number who develop MS is smaller still. They found what they needed in the records of the National Health Service of England. Among over 21,000 HIV-positive patients, they found only seven MS patients, when (according to a non-HIV-infected control group) there should have been 18. In other words, HIV-positive patients being treated for their disease were 60% less likely to develop MS. The results are published in the Journal of Neurology, Neurosurgery, and Psychiatry.
MS develops when the patient's immune system attacks the sheaths protecting nerve cells in the central nervous system. Some researchers think that the trigger causing the immune system to attack is an unknown virus. If so, there's a good possibility that the antiviral cocktail used to treat HIV is also attacking this unknown virus, thereby reducing the risk of developing MS.
Much more research needs to be done before we can be sure. But here's a case where the curiosity of an observant doctor may ultimately lead to an effective treatment for MS.
To find out, the doctor and his coworkers needed access to the records of a large number of patients, because the number of people in a population who are HIV-positive is not all that large, and the number who develop MS is smaller still. They found what they needed in the records of the National Health Service of England. Among over 21,000 HIV-positive patients, they found only seven MS patients, when (according to a non-HIV-infected control group) there should have been 18. In other words, HIV-positive patients being treated for their disease were 60% less likely to develop MS. The results are published in the Journal of Neurology, Neurosurgery, and Psychiatry.
MS develops when the patient's immune system attacks the sheaths protecting nerve cells in the central nervous system. Some researchers think that the trigger causing the immune system to attack is an unknown virus. If so, there's a good possibility that the antiviral cocktail used to treat HIV is also attacking this unknown virus, thereby reducing the risk of developing MS.
Much more research needs to be done before we can be sure. But here's a case where the curiosity of an observant doctor may ultimately lead to an effective treatment for MS.
Sunday, August 31, 2014
Organic Foods Contain More Antioxidants
Back in 2012, a comprehensive meta-analysis of many previous studies concluded that in terms of nutrition, organic foods are generally no better for you than non-organic foods (this blog Sept. 6, 2012). Of course, that didn’t sit too well with supporters of the organic food movement. Well finally, proponents of organic foods have something to talk about, too. Another comprehensive meta-analysis, this one by primarily European researchers, concludes that organic foods have fewer pesticides and more antioxidants than non-organic foods.
The finding of fewer pesticides is to be expected, of course, since the pesticides they’re talking about aren’t supposed to be used on organically grown crops in the first place. The same was found in the previous nutritional study. The finding that organic foods contain more antioxidants will be welcomed by supporters of organic foods. As you may know, antioxidants are thought to be protective against cell damage, and hence could (in theory) assist in delaying cellular aging and possibly reducing the risk of cancer.
Unfortunately, “in theory” does not always coincide with “in reality”. Neither group of authors is claiming that eating organic foods actually leads to better health, because at the moment there is no evidence to support such a claim. If its better health we want, we should concentrate on eating more fruits and vegetables of either kind (organic or non-organic) according to our preference, and less refined sugar and fat.
The finding of fewer pesticides is to be expected, of course, since the pesticides they’re talking about aren’t supposed to be used on organically grown crops in the first place. The same was found in the previous nutritional study. The finding that organic foods contain more antioxidants will be welcomed by supporters of organic foods. As you may know, antioxidants are thought to be protective against cell damage, and hence could (in theory) assist in delaying cellular aging and possibly reducing the risk of cancer.
Unfortunately, “in theory” does not always coincide with “in reality”. Neither group of authors is claiming that eating organic foods actually leads to better health, because at the moment there is no evidence to support such a claim. If its better health we want, we should concentrate on eating more fruits and vegetables of either kind (organic or non-organic) according to our preference, and less refined sugar and fat.
Saturday, August 23, 2014
Illegal Human Organ Trafficking
It is illegal to sell or buy human organs in most countries. It is also against the principles of the Transplant Society and the International Society of Nephrology, whose joint Declaration of Istanbul states that organ trafficking and transplant tourism “ violate the principle of equity, justice, and respect for human dignity and should be prohibited.”
But where there’s money to be made, someone will try to make it. As the gap between the demand for kidneys and their supply (from cadavers or live donors) continues to widen, unscrupulous underground “businessmen” manage to bring desperate patients and willing sellers together, for money. If you can find one of these kidney brokers, the going price seems to be nearly $200,000 to buy a kidney, but less than $20,000 to sell one.
Kidney brokers are rarely caught and convicted, in part because they may not live on the same continent as the buyer and seller. So where exactly is the crime committed? Furthermore, brokers claim to enlist only altruistic donors who are not paid. They tell the potential buyer that the high price is to “cover expenses”. Donors are paid under the table and then coached to say that they are not doing it for money. No one really believes that, however, when the donor is from Costa Rica and the patient (a total stranger) is from Israel or the U.S. Desperate buyers are willing to turn a blind eye to the truth when their life is at stake. For a peek into this shadowy world, see the New York Times article on the subject or visit the Declaration of Istanbul website highlighted above.
Reasonable people have argued that the only way to eliminate the black market in human organs is to permit the buying and selling of organs, subject to controls to protect potential donors. They argue that thousands of lives could be saved every year. Whether buying/selling organs could be done without undue coercion of the poor is still an open question. At least one study in this country suggests that perhaps it could (this blog, April 26, 2010.) I’m not convinced, however, that the same results would hold in places where people are truly desperate, and not just below the average U.S. income. I’m reserving judgment on this idea for now.
But where there’s money to be made, someone will try to make it. As the gap between the demand for kidneys and their supply (from cadavers or live donors) continues to widen, unscrupulous underground “businessmen” manage to bring desperate patients and willing sellers together, for money. If you can find one of these kidney brokers, the going price seems to be nearly $200,000 to buy a kidney, but less than $20,000 to sell one.
Kidney brokers are rarely caught and convicted, in part because they may not live on the same continent as the buyer and seller. So where exactly is the crime committed? Furthermore, brokers claim to enlist only altruistic donors who are not paid. They tell the potential buyer that the high price is to “cover expenses”. Donors are paid under the table and then coached to say that they are not doing it for money. No one really believes that, however, when the donor is from Costa Rica and the patient (a total stranger) is from Israel or the U.S. Desperate buyers are willing to turn a blind eye to the truth when their life is at stake. For a peek into this shadowy world, see the New York Times article on the subject or visit the Declaration of Istanbul website highlighted above.
Reasonable people have argued that the only way to eliminate the black market in human organs is to permit the buying and selling of organs, subject to controls to protect potential donors. They argue that thousands of lives could be saved every year. Whether buying/selling organs could be done without undue coercion of the poor is still an open question. At least one study in this country suggests that perhaps it could (this blog, April 26, 2010.) I’m not convinced, however, that the same results would hold in places where people are truly desperate, and not just below the average U.S. income. I’m reserving judgment on this idea for now.
Wednesday, August 20, 2014
Why Societies Collapse
Why have some of the greatest human societies of all time essentially collapsed to insignificance, or at least undergone steep declines? What fate awaits today’s most important societies, or even the human race as a whole? Is collapse inevitable?
A study to be published in Ecological Economics offers some interesting observations on these questions, based on a mathematical modeling analysis of past societies. According to the authors of the paper, two commonly-observed events associated with societal collapse or steep decline are; 1) resource over-use beyond carrying capacity, and 2) social stratification (increased separation into rich versus poor). The first factor should be obvious to any student of biology: Any population, whether it be bacteria or humans, must ultimately undergo a decline in population or at least a decline in living standards if it depletes the resources available to it. That concept is at the heart of the philosophy that ultimately humans must learn to live within a “sustainable world” if we are to stay healthy, happy, and successful.
The second factor, social stratification, is not so obvious. The authors propose several ways that increased separation between rich and poor could affect a society. One might be that the rich over-utilize resources, leaving too few resources for the poor. Another could be that as the poor make it into the rich category, there are too few workers left to do a society’s work.
Press reports of the study have made it sound as if we’re doomed. But nothing about the study implies that at all. There’s no reason why an enlightened society couldn’t make an effort to minimize social stratification and learn to use its resources wisely. Forewarned is forearmed.
A study to be published in Ecological Economics offers some interesting observations on these questions, based on a mathematical modeling analysis of past societies. According to the authors of the paper, two commonly-observed events associated with societal collapse or steep decline are; 1) resource over-use beyond carrying capacity, and 2) social stratification (increased separation into rich versus poor). The first factor should be obvious to any student of biology: Any population, whether it be bacteria or humans, must ultimately undergo a decline in population or at least a decline in living standards if it depletes the resources available to it. That concept is at the heart of the philosophy that ultimately humans must learn to live within a “sustainable world” if we are to stay healthy, happy, and successful.
The second factor, social stratification, is not so obvious. The authors propose several ways that increased separation between rich and poor could affect a society. One might be that the rich over-utilize resources, leaving too few resources for the poor. Another could be that as the poor make it into the rich category, there are too few workers left to do a society’s work.
Press reports of the study have made it sound as if we’re doomed. But nothing about the study implies that at all. There’s no reason why an enlightened society couldn’t make an effort to minimize social stratification and learn to use its resources wisely. Forewarned is forearmed.
Friday, August 15, 2014
First Antibiotic-Resistant Bacteria; Now Herbicide-Resistant Weeds
Nearly all of the corn and soybeans planted in this country have been genetically modified to make them resistant to a common herbicide called Roundup (glyphosate). Such genetically modified organisms (GMOs) can be sprayed with Roundup during the growing season to kill weeds without harming the crop.
Given what we know about how the over-use of antibiotics has led to the appearance of antibiotic-resistant strains of bacteria, what did we think would happen when we began spraying GMO crops heavily with a single herbicide? Why, of course - Roundup-resistant weeds! According to a recent New York Times article, an invasive Roundup-resistant weed called palmer amaranth (carelessweed) is already sweeping northward from the south, wreaking havoc on farmers’ fields.
Monsanto, the manufacturer of Roundup and the developer of the GMO seeds most farmers now plant, is planning even more genetic modification of corn and soybeans to make them resistant to other herbicides as well, allowing farmers to spray more than one herbicide on their crops. Each new modification will buy farmers some time in the perpetual battle against weeds (and also enrich Monsanto). But it’s not hard to see that in the long run this is a losing game; the over-use of any herbicide will ultimately lead to the emergence of herbicide-resistant weeds. Adaptation and evolution are hallmarks of the natural world. Farmers will have to develop other approaches (in addition to just spraying herbicides) to combat weeds effectively.
Given what we know about how the over-use of antibiotics has led to the appearance of antibiotic-resistant strains of bacteria, what did we think would happen when we began spraying GMO crops heavily with a single herbicide? Why, of course - Roundup-resistant weeds! According to a recent New York Times article, an invasive Roundup-resistant weed called palmer amaranth (carelessweed) is already sweeping northward from the south, wreaking havoc on farmers’ fields.
Monsanto, the manufacturer of Roundup and the developer of the GMO seeds most farmers now plant, is planning even more genetic modification of corn and soybeans to make them resistant to other herbicides as well, allowing farmers to spray more than one herbicide on their crops. Each new modification will buy farmers some time in the perpetual battle against weeds (and also enrich Monsanto). But it’s not hard to see that in the long run this is a losing game; the over-use of any herbicide will ultimately lead to the emergence of herbicide-resistant weeds. Adaptation and evolution are hallmarks of the natural world. Farmers will have to develop other approaches (in addition to just spraying herbicides) to combat weeds effectively.
Saturday, August 9, 2014
Two Experimental Drugs Used to Treat Ebola
Desperate times call for desperate measures.
Two drugs are currently being used to treat patients with Ebola hemorrhagic fever (Ebola). Both are relatively untested, meaning they are a long way from being formally approved by the FDA. But when the choice is between watching patients die or trying something, it seems that trying something wins out.
The use of untested drugs and/or drugs in very short supply raises all kinds of ethical issues, of course. The first drug, called ZMapp, had never been tried on humans before now. It was first used on the two Americans who contracted the disease in Liberia and who have since been flown to Atlanta. Aside from the issue of risk to the two patients, there’s the troubling ethical question of favoritism; why was it given to the two Americans first, and not to any of the many African patients? (On the other hand, had it been given first to Africans, there would be complaints that Africans were being used as guinea pigs. You can’t win this one!).
The second drug, called TKM-Ebola, was already in the human testing phase when the Ebola epidemic began. But the tests, which were being conducted on normal human volunteers, had been halted temporarily because of side effects in one volunteer. Given the current situation, though, the FDA took the unprecedented step of approving TKM-Ebola for Ebola patients anyway. Apparently the FDA felt that the potential benefits to patients who actually had Ebola far outweighed the risks.
It takes time to ramp up the production of any drug. Both drugs will be in short supply in the near future, which means that choosing which patients will get them will remain an issue for a while. From a medical point of view, it’ll be interesting to see how effective they actually are.
Two drugs are currently being used to treat patients with Ebola hemorrhagic fever (Ebola). Both are relatively untested, meaning they are a long way from being formally approved by the FDA. But when the choice is between watching patients die or trying something, it seems that trying something wins out.
The use of untested drugs and/or drugs in very short supply raises all kinds of ethical issues, of course. The first drug, called ZMapp, had never been tried on humans before now. It was first used on the two Americans who contracted the disease in Liberia and who have since been flown to Atlanta. Aside from the issue of risk to the two patients, there’s the troubling ethical question of favoritism; why was it given to the two Americans first, and not to any of the many African patients? (On the other hand, had it been given first to Africans, there would be complaints that Africans were being used as guinea pigs. You can’t win this one!).
The second drug, called TKM-Ebola, was already in the human testing phase when the Ebola epidemic began. But the tests, which were being conducted on normal human volunteers, had been halted temporarily because of side effects in one volunteer. Given the current situation, though, the FDA took the unprecedented step of approving TKM-Ebola for Ebola patients anyway. Apparently the FDA felt that the potential benefits to patients who actually had Ebola far outweighed the risks.
It takes time to ramp up the production of any drug. Both drugs will be in short supply in the near future, which means that choosing which patients will get them will remain an issue for a while. From a medical point of view, it’ll be interesting to see how effective they actually are.
Tuesday, August 5, 2014
An Ebola Outbreak in West Africa
A recent outbreak of a viral disease called Ebola hemorrhagic fever (Ebola HF) has killed over 700 people in the West African nations of Guinea, Liberia, and Sierra Leone. Infected persons initially exhibit symptoms including a fever, fatigue, and joint, muscle and abdominal pain, similar to the flu. But unlike the flu, Ebola HF interferes with mechanisms involved in blood clotting, ultimately leading to hemorrhage in multiple organs. Over 55% of all persons infected with Ebola HF have died, making Ebola HF one of the most deadly viral diseases currently infecting humans.
Before you get too worried, you should know that the virus that causes Ebola HF is NOT transmitted through the air (like the common cold) or even by casual physical contact (e.g. a handshake). It is transmitted primarily through direct contact with bodily fluids. Persons most at risk are people who live with an infected person, health care workers, and persons who work with infected cadavers, such as funeral workers. The availability of good medical care (not always available in West Africa) reduces the death rate significantly. So far, two Americans have contracted the disease while working in Liberia; both have been transported to the U.S. and are being treated in a special medical unit at Emory University in Atlanta. Both are expected to recover.
The CDC will be sending 50 additional disease experts to the region within the next month in an effort to contain the outbreak. For updates and more information about Ebola HF, see the CDC’s website page on the topic.
Is there anything you should be doing right now to protect yourself? Well, yes… according to the CDC you should “avoid nonessential travel to the west African nations of Guinea, Liberia, and Sierra Leone”. Shouldn’t be too hard for most of us.
Before you get too worried, you should know that the virus that causes Ebola HF is NOT transmitted through the air (like the common cold) or even by casual physical contact (e.g. a handshake). It is transmitted primarily through direct contact with bodily fluids. Persons most at risk are people who live with an infected person, health care workers, and persons who work with infected cadavers, such as funeral workers. The availability of good medical care (not always available in West Africa) reduces the death rate significantly. So far, two Americans have contracted the disease while working in Liberia; both have been transported to the U.S. and are being treated in a special medical unit at Emory University in Atlanta. Both are expected to recover.
The CDC will be sending 50 additional disease experts to the region within the next month in an effort to contain the outbreak. For updates and more information about Ebola HF, see the CDC’s website page on the topic.
Is there anything you should be doing right now to protect yourself? Well, yes… according to the CDC you should “avoid nonessential travel to the west African nations of Guinea, Liberia, and Sierra Leone”. Shouldn’t be too hard for most of us.
Friday, August 1, 2014
Synthetic Human Growth Hormone Use by Teens
An increasing number of teens are using synthetic human growth hormone (HGH) to enhance their appearance and/or their athletic performance, according to the latest survey from the Partnership for Drug-Free Kids. Eleven percent of teens now say that they have used HGH at least once, up from 5% just a year ago. Girls are nearly as likely to use HGH as boys. Teens’ attitudes are changing, too; fewer teens report that there is a moderate or great risk associated with performance-enhancing drugs than in past years. The full survey on teens’ attitudes toward HGH and other performance-enhancing steroids, as well as marijuana and prescription medicines, can be accessed here.
Whether HGH actually does enhance teens’ appearance or athletic performance is still an open question. WebMD calls the effects of HGH on athletic performance “unknown”. Nor is it known whether there are any long-term negative effects of HGH use on health. And finally, there are no guarantees that HGH products sold illegally over the Internet actually contain HGH, as advertised.
The U.S. Food and Drug Administration (FDA), the agency responsible for regulating medical drugs, has approved HGH for use by prescription only, for specific medical conditions. It does not have the resources to prevent Internet sales of HGH, any more than the police are able to stop illicit prescription drug or marijuana use. Teens are taking a risk by buying HCG over the internet, without a prescription.
For more on this subject, go to a previous blog post titled "Athlete Caught Doping with Growth Hormone."
Whether HGH actually does enhance teens’ appearance or athletic performance is still an open question. WebMD calls the effects of HGH on athletic performance “unknown”. Nor is it known whether there are any long-term negative effects of HGH use on health. And finally, there are no guarantees that HGH products sold illegally over the Internet actually contain HGH, as advertised.
The U.S. Food and Drug Administration (FDA), the agency responsible for regulating medical drugs, has approved HGH for use by prescription only, for specific medical conditions. It does not have the resources to prevent Internet sales of HGH, any more than the police are able to stop illicit prescription drug or marijuana use. Teens are taking a risk by buying HCG over the internet, without a prescription.
For more on this subject, go to a previous blog post titled "Athlete Caught Doping with Growth Hormone."
Sunday, July 27, 2014
A New Drug for Type 2 Diabetics
In normal people, insulin causes sugar to be taken up by cells, especially in muscle, liver, and fat. But in Type 2 diabetics, insulin loses its effectiveness, and as a result too much sugar remains in the blood. Most of the drugs currently used to treat diabetes improve cells’ ability to take up sugar from the bloodstream, thereby lowering the blood sugar level back toward normal.
Now there’s a new drug that works in an entirely different way. Invokana was developed based on a basic knowledge of how the kidneys handle blood sugar. Normally, all of the sugar that is filtered in the kidneys is reabsorbed back into the bloodstream; none is excreted in the urine. It’s nature’s way of conserving energy (sugar). The mechanism of sugar reabsorption involves sugar transport “pumps” (comprised of certain proteins) in cells of the renal tubules. Invokana blocks those sugar transport pumps, so some of the some of the filtered sugar is not reabsorbed. Instead, it is excreted from the body in the urine. In diabetics (whose blood sugar is too high), that's a good thing, because it lowers the blood sugar level.
One of the potential side effects of Invokana is a slight loss of weight. That makes sense when you think about it; sugar lost in the urine equals calories lost. In diabetics who are also overweight, that could be a good thing. But I see a real danger here; what if people are led believe that Invokana would work as a diet pill (“just pee those extra calories out!”) and a black market develops for it?
I hope that doesn’t happen. There’s no data yet to prove that Invokana would result in enough weight loss to make a dieter happy. More importantly, in a person with a normal blood sugar level to begin with, Invokana might lower blood sugar to dangerously low levels. Unfortunately, people are willing to believe some pretty crazy things when marketers (black-marketers or otherwise) give them just a grain of truth.
Now there’s a new drug that works in an entirely different way. Invokana was developed based on a basic knowledge of how the kidneys handle blood sugar. Normally, all of the sugar that is filtered in the kidneys is reabsorbed back into the bloodstream; none is excreted in the urine. It’s nature’s way of conserving energy (sugar). The mechanism of sugar reabsorption involves sugar transport “pumps” (comprised of certain proteins) in cells of the renal tubules. Invokana blocks those sugar transport pumps, so some of the some of the filtered sugar is not reabsorbed. Instead, it is excreted from the body in the urine. In diabetics (whose blood sugar is too high), that's a good thing, because it lowers the blood sugar level.
One of the potential side effects of Invokana is a slight loss of weight. That makes sense when you think about it; sugar lost in the urine equals calories lost. In diabetics who are also overweight, that could be a good thing. But I see a real danger here; what if people are led believe that Invokana would work as a diet pill (“just pee those extra calories out!”) and a black market develops for it?
I hope that doesn’t happen. There’s no data yet to prove that Invokana would result in enough weight loss to make a dieter happy. More importantly, in a person with a normal blood sugar level to begin with, Invokana might lower blood sugar to dangerously low levels. Unfortunately, people are willing to believe some pretty crazy things when marketers (black-marketers or otherwise) give them just a grain of truth.
Sunday, July 20, 2014
The Cost of Not Understanding Risk
Many women believe that annual or biennial mammograms will dramatically reduce the risk of dying of breast cancer. Statistics prove them wrong, however. For more on risk versus women’s beliefs about risk when it comes to mammograms, see the New York Times article entitled “Universal Mammograms Shows We Don’t Understand Risk”.
You might think that understanding risk not that important. Think again. Screening all women over the age of 50 for breast cancer every other year is expensive. If it’s not going to save a significant number of lives (i.e. isn’t cost/effective), perhaps that money could be better spent on something that does have a significant effect on women’s health.
It’s not my intent to pick just on women here - men believe that screening for prostate cancer saves lots of lives, too, but it doesn’t. I’m also not arguing against screening tests in general, or against mammograms or prostate tests for individuals at high risk. Screening tests have a valuable place in our health care system. Let’s just use them wisely.
You might think that understanding risk not that important. Think again. Screening all women over the age of 50 for breast cancer every other year is expensive. If it’s not going to save a significant number of lives (i.e. isn’t cost/effective), perhaps that money could be better spent on something that does have a significant effect on women’s health.
It’s not my intent to pick just on women here - men believe that screening for prostate cancer saves lots of lives, too, but it doesn’t. I’m also not arguing against screening tests in general, or against mammograms or prostate tests for individuals at high risk. Screening tests have a valuable place in our health care system. Let’s just use them wisely.
Sunday, July 13, 2014
The Economic Impact of Climate Change
One of the problems with any discussion of climate change these days is that there is very little good information about the potential effects of climate change on the economy. Without such information, how can we decide what actions to take to slow or mitigate climate change’s economic impacts? Some politicians continue to deny that climate change even exists. I think its because acknowledging the problem would mean that we’d have to do something about it, and any fix is going to cost a lot of money. So we continue to avoid dealing with climate change….
In an effort to shed some light on the potential economic impacts of climate change, an independent, non-partisan group of business people and politicians has prepared an economic risk analysis of climate change. The group examined all of the current research findings available. The final document, called the Risky Business report, describes some of the potential impacts of climate change, region by region.
A key takeaway message from the report is that whether its an increase in sea level, changes in temperature or rainfall, or increased tornadoes/hurricanes, different regions of the country are going to be affected differently. You can access the Risky Business report here to see how your region of the country is likely to be affected.
In an effort to shed some light on the potential economic impacts of climate change, an independent, non-partisan group of business people and politicians has prepared an economic risk analysis of climate change. The group examined all of the current research findings available. The final document, called the Risky Business report, describes some of the potential impacts of climate change, region by region.
A key takeaway message from the report is that whether its an increase in sea level, changes in temperature or rainfall, or increased tornadoes/hurricanes, different regions of the country are going to be affected differently. You can access the Risky Business report here to see how your region of the country is likely to be affected.
Wednesday, July 9, 2014
The One-Dollar Microscope
A microscope that costs less than a dollar? The Foldscope is made primarily of paper, plus a sapphire ball lens, a LED light source, and a small button battery. It can be easily folded (assembled) into a working 2000-x microscope within minutes. Although not as versatile as a microscope costing hundreds of dollars, the Foldscope is good enough that one can see individual cells in a sample, and even identify some bacteria and tropical diseases such as malaria and schistosomiasis.
The Foldscope was designed by scientists at Stanford University. It is currently being tested by the first 10,000 persons who signed up to receive one. From their many experiences, the volunteers will also help develop a crowd-sourced microscopy manual. The goal of the scientists who developed the Foldscope was to create a simple cost-effective tool that could be used to stimulate curiosity in science and biology. It may also have applications in global health.
You can’t buy a Foldscope just yet. But at only a dollar apiece it may not be long before they are standard issue in most schools, and also in health clinics in poor countries.
The Foldscope was designed by scientists at Stanford University. It is currently being tested by the first 10,000 persons who signed up to receive one. From their many experiences, the volunteers will also help develop a crowd-sourced microscopy manual. The goal of the scientists who developed the Foldscope was to create a simple cost-effective tool that could be used to stimulate curiosity in science and biology. It may also have applications in global health.
You can’t buy a Foldscope just yet. But at only a dollar apiece it may not be long before they are standard issue in most schools, and also in health clinics in poor countries.
Sunday, July 6, 2014
Inhalable Insulin, Round Three
Last month the FDA approved yet another inhalable insulin product for use in controlling blood sugar in Type 1 and Type 2 diabetics. The new product (called Afreeza) delivers powdered insulin via an inhaler similar to those used by asthmatics. Designed to be used before each meal, Afreeza is apparently one of the most rapidly acting insulin products available.
It’ll be interesting to see whether anyone cares any more this time than they did last time. Inhalable insulin products have been attempted twice before, and both times the products were spectacular failures. Pfizer was the first pharmaceutical company to bring an inhalable insulin product (called Exubera) to market, back in 2006. The company quit making Exubera after just a year due to poor sales. Shortly thereafter, Eli Lilly halted the development of its own inhalable insulin product before it even came to market (see "Inhaled Insulin - Who Cares?").
But even in the face of these spectacular failures, it’s been hard for pharmaceutical companies to give up on the idea. The market for diabetes treatment products is huge – there are nearly 30 million diabetics in the U.S. alone. Even a small part of the sales of diabetic products would be a huge boost to the bottom line of most pharmaceutical companies. MannKind, the small company that spent nearly $2 billion developing Afreeza over the last decade, thinks that Afreeza will prove to be successful where others failed. But don’t hold your breath. Pfizer’s experience was that diabetics really didn’t mind their syringes and small needles all that much. Whether an inhalable insulin product ever gains widespread market acceptance may boil down to price.
It’ll be interesting to see whether anyone cares any more this time than they did last time. Inhalable insulin products have been attempted twice before, and both times the products were spectacular failures. Pfizer was the first pharmaceutical company to bring an inhalable insulin product (called Exubera) to market, back in 2006. The company quit making Exubera after just a year due to poor sales. Shortly thereafter, Eli Lilly halted the development of its own inhalable insulin product before it even came to market (see "Inhaled Insulin - Who Cares?").
But even in the face of these spectacular failures, it’s been hard for pharmaceutical companies to give up on the idea. The market for diabetes treatment products is huge – there are nearly 30 million diabetics in the U.S. alone. Even a small part of the sales of diabetic products would be a huge boost to the bottom line of most pharmaceutical companies. MannKind, the small company that spent nearly $2 billion developing Afreeza over the last decade, thinks that Afreeza will prove to be successful where others failed. But don’t hold your breath. Pfizer’s experience was that diabetics really didn’t mind their syringes and small needles all that much. Whether an inhalable insulin product ever gains widespread market acceptance may boil down to price.
Wednesday, July 2, 2014
Alicia Silverstone is Clueless (Again)
The latest actress to speak out against childhood vaccines is Alicia Silverstone, best known for the 1995 hit movie, “Clueless”. The actress had a baby several years ago, and apparently she thinks that qualifies her to give advice to future mothers. In her new book entitled “The Kind Mama: A Simple Guide to Supercharged Fertility, a Radiant Pregnancy, a Sweeter Birth, and a Healthier, More Beautiful Beginning”, the actress makes unsubstantiated claims about natural plant-based diets; claims tampons may cause infertility; and questions the safety of vaccines.
Regarding the schedule of childhood vaccines, she reports anecdotal concerns by other parents because she can’t find the scientific evidence to support her claim. She writes, “While there has not been a conclusive study of the negative effects of such a rigorous one-size-fits-all, shoot-‘em-up schedule, there is increasing anecdotal evidence from doctors who have gotten distressed phone calls from parents claiming their child was ‘never the same’ after receiving a vaccine. And I personally have friends whose babies were drastically affected in this way.”
She’s entitled to say whatever she wants, of course. The rest of us shouldn’t listen. Numerous scientific studies have failed to establish any link between vaccines and certain conditions such as autism, because there isn’t any link. Whether or not to vaccinate children shouldn’t still be an issue.
Regarding the schedule of childhood vaccines, she reports anecdotal concerns by other parents because she can’t find the scientific evidence to support her claim. She writes, “While there has not been a conclusive study of the negative effects of such a rigorous one-size-fits-all, shoot-‘em-up schedule, there is increasing anecdotal evidence from doctors who have gotten distressed phone calls from parents claiming their child was ‘never the same’ after receiving a vaccine. And I personally have friends whose babies were drastically affected in this way.”
She’s entitled to say whatever she wants, of course. The rest of us shouldn’t listen. Numerous scientific studies have failed to establish any link between vaccines and certain conditions such as autism, because there isn’t any link. Whether or not to vaccinate children shouldn’t still be an issue.
Wednesday, June 25, 2014
Childhood Vaccination Policy Challenged in Court
How do we balance the rights of an child to attend school against the need to protect society from disease? In New York City, children must be vaccinated against certain vaccine-preventable diseases in order to attend school, unless the child has been granted an exemption on either medical or religious grounds. The vaccination requirement is intended to protect society from disease; the exemption allows for the rights of an individual under certain special circumstances. So far, so good. But there's a catch...
To protect both the unvaccinated child and society as a whole from disease, New York City added an additional feature to its vaccination policy. In New York City, unvaccinated children can be barred from school whenever another child at the school has a vaccine-preventable disease. The policy that their child can be barred from school, even if only temporarily, does not sit well with some parents of unvaccinated children. The parents of two unvaccinated children sued the city, arguing that barring unvaccinated children from school violates their rights under the 14th amendment to the U.S. constitution. The 14th amendment, as you probably know, guarantees all citizens equal protection under the law. But does that include the right of an unvaccinated child to attend school, even when it puts themselves and others at risk?
The case is wending its way through the courts. Just this month a judge of the Federal District Court in Brooklyn ruled in favor of the school system, arguing that there’s nothing in the constitution that speaks to the issue of religion-based exemptions from vaccinations. This case will almost certainly be appealed.
To protect both the unvaccinated child and society as a whole from disease, New York City added an additional feature to its vaccination policy. In New York City, unvaccinated children can be barred from school whenever another child at the school has a vaccine-preventable disease. The policy that their child can be barred from school, even if only temporarily, does not sit well with some parents of unvaccinated children. The parents of two unvaccinated children sued the city, arguing that barring unvaccinated children from school violates their rights under the 14th amendment to the U.S. constitution. The 14th amendment, as you probably know, guarantees all citizens equal protection under the law. But does that include the right of an unvaccinated child to attend school, even when it puts themselves and others at risk?
The case is wending its way through the courts. Just this month a judge of the Federal District Court in Brooklyn ruled in favor of the school system, arguing that there’s nothing in the constitution that speaks to the issue of religion-based exemptions from vaccinations. This case will almost certainly be appealed.
Saturday, June 21, 2014
An Anti-aging Blood Protein
A blood protein called Growth Differentiation Factor 11 (GDF11) is one of the factors that keeps tissues and organs youthful. According to research described in a New York Times article, GDF11 stimulates stem cells within tissues, promoting tissue growth and regeneration.
Not surprisingly, GDF11 is abundant in young animals, but less abundant in older animals. But here’s the really interesting part; transfusing old mice with the blood of younger animals or giving them GDF11 appears to reverse some of the effects of aging, at least in mice.
That last finding has caught the public’s eye. People are already asking how to get the stuff on the Internet so they can use it on themselves to try to reverse some of the effects of aging. From an individual’s perspective that may seem like a good idea (who wouldn’t want to live longer and feel younger?) But is it really such a good idea?
From a evolutionary biologist’s perspective, it makes sense that GDF11 is found in higher concentrations in the young than the old. Tissues and organs are still growing and differentiating in the young, so you need the stuff. But after reproductive age, GDF11’s importance declines. Aging and death are just a normal part of the life cycle. In fact, it appears that we’re programmed in our genes to age and die once we are safely past reproductive age. Yes, we might be able to turn back the clock a little in an individual, but there may be a hidden risk; by encouraging stem cells to divide and differentiate we’d probably be increasing the risk of cancer cell as well.
A basic understanding of how GDF11 regulates normal cell growth and differentiation is certainly of interest. It may even lead to treatments for specific disorders, such as muscle wasting disorders or Alzheimer’s disease. But it’s highly unlikely that GDF11 will prove be the magic elixir that can turn back the clock on aging. There’s undoubtedly a lot more to aging than the slow decline in the concentration of a single blood protein.
Not surprisingly, GDF11 is abundant in young animals, but less abundant in older animals. But here’s the really interesting part; transfusing old mice with the blood of younger animals or giving them GDF11 appears to reverse some of the effects of aging, at least in mice.
That last finding has caught the public’s eye. People are already asking how to get the stuff on the Internet so they can use it on themselves to try to reverse some of the effects of aging. From an individual’s perspective that may seem like a good idea (who wouldn’t want to live longer and feel younger?) But is it really such a good idea?
From a evolutionary biologist’s perspective, it makes sense that GDF11 is found in higher concentrations in the young than the old. Tissues and organs are still growing and differentiating in the young, so you need the stuff. But after reproductive age, GDF11’s importance declines. Aging and death are just a normal part of the life cycle. In fact, it appears that we’re programmed in our genes to age and die once we are safely past reproductive age. Yes, we might be able to turn back the clock a little in an individual, but there may be a hidden risk; by encouraging stem cells to divide and differentiate we’d probably be increasing the risk of cancer cell as well.
A basic understanding of how GDF11 regulates normal cell growth and differentiation is certainly of interest. It may even lead to treatments for specific disorders, such as muscle wasting disorders or Alzheimer’s disease. But it’s highly unlikely that GDF11 will prove be the magic elixir that can turn back the clock on aging. There’s undoubtedly a lot more to aging than the slow decline in the concentration of a single blood protein.
Sunday, June 15, 2014
Saving Trauma Patients with Ice-Cold Saline?
According to a New York Times article, surgeons at the University of Pittsburgh Medical Center have been given approval to begin a unique clinical trial on certain trauma patients. In severe trauma patients, for example those with knife or gunshot wounds who have already lost so much blood that their heartbeat has ceased, the surgeons will rapidly replace the patient’s blood with ice-cold salt water before undertaking life-saving surgery.
Cooling the blood is routinely used to stop the heart before open-heart surgery. Lowering the body’s temperature lowers its metabolic rate, slowing the onset of tissue death and thus buying surgeons precious time. But replacing a patient’s blood entirely with ice-cold salt water is new. At such cold temperatures the patients will be devoid of brain activity, and thus the patient will appear to be dead.
Because of the unforeseen nature of their trauma, the patients in this study will not be in a position to give their informed consent. Nevertheless, the clinical trial apparently has been approved by whatever ethics committees needed to sign off on it. Presumably there is little to be lost, and everything to be gained, by at least giving it a try.
It’ll be interesting to hear the patients’ experiences of being “brought back” from a state of no brain activity.
Cooling the blood is routinely used to stop the heart before open-heart surgery. Lowering the body’s temperature lowers its metabolic rate, slowing the onset of tissue death and thus buying surgeons precious time. But replacing a patient’s blood entirely with ice-cold salt water is new. At such cold temperatures the patients will be devoid of brain activity, and thus the patient will appear to be dead.
Because of the unforeseen nature of their trauma, the patients in this study will not be in a position to give their informed consent. Nevertheless, the clinical trial apparently has been approved by whatever ethics committees needed to sign off on it. Presumably there is little to be lost, and everything to be gained, by at least giving it a try.
It’ll be interesting to hear the patients’ experiences of being “brought back” from a state of no brain activity.
Sunday, June 8, 2014
Sunburns, Teenagers, and Melanoma
A study of over 100,000 U.S. Caucasian women who were followed for 20 years confirms what we’ve long suspected; that too many sunburns early in life increases one’s risk of melanoma, the deadliest form of skin cancer. The study, published recently in Cancer Epidemiology, Biomarkers and Prevention, showed that women who reported having had at least five blistering sunburns during their teenage years had almost a 3-fold greater risk of developing a melanoma over the next 20 years, compared to women who never were sunburned in their teenage years.
Interestingly, the same did not hold true for older women who routinely exposed themselves to high amounts of ultraviolet radiation. Although their risks of several other types of less deadly skin cancers were increased by increased exposure to ultraviolet radiation, the risk of melanoma did not increase significantly.
Bottom line; it is particularly important that children and teenagers should be protected from sunburns. Skin damage early in life sets the stage for melanoma, and nobody needs that when protecting yourself and your children is so easy these days.
Interestingly, the same did not hold true for older women who routinely exposed themselves to high amounts of ultraviolet radiation. Although their risks of several other types of less deadly skin cancers were increased by increased exposure to ultraviolet radiation, the risk of melanoma did not increase significantly.
Bottom line; it is particularly important that children and teenagers should be protected from sunburns. Skin damage early in life sets the stage for melanoma, and nobody needs that when protecting yourself and your children is so easy these days.
Friday, June 6, 2014
A New Antibiotic for Use Against MRSA
A new antibiotic still under development that may offer the best defense yet against the flesh-eating bacteria called methicillin-resistant Staphyllococcus aureus (MRSA). It's called oritavancin. In recent tests, just a single dose of oritavancin proved just as effective against MRSA as a full 10-day course of intravenous vancomycin, the current best treatment for MRSA. That means that with oritavancin, a patient with MRSA could be given just a single treatment in an outpatient setting, without any need for hospitalization. In contrast, treatment with vancomycin usually requires a lengthy hospital stay. The cost savings in hospitalization alone would be huge. But with that potential cost savings in mind, it’s likely that the drug’s manufacturer will charge a lot for oritavancin.
One downside is that when a patient is treated with a single dose of a drug and sent home, doctors have less oversight over whether the drug is working or not. A protocol may need to be developed in which someone checks on the patient over the first few days after treatment.
The FDA is likely to approve oritavancin by this Fall under a program that fast-tracks promising new drugs.
One downside is that when a patient is treated with a single dose of a drug and sent home, doctors have less oversight over whether the drug is working or not. A protocol may need to be developed in which someone checks on the patient over the first few days after treatment.
The FDA is likely to approve oritavancin by this Fall under a program that fast-tracks promising new drugs.
Tuesday, June 3, 2014
Pregnant Women Have More Auto Accidents
According to a new study of more than half a million pregnant Canadian women, pregnancy is a risk factor for having an auto accident. Overall, women are 42% more likely to have a serious auto accident during pregnancy than before pregnancy.
Is it because pregnant women become distracted when the baby kicks? No, because the increased risk of an auto accident peaks in the fourth month of pregnancy, before the fetus is kicking. After the fourth month of pregnancy the risk declines each month until childbirth. And it doesn’t seem to matter whether it’s a first pregnancy or a subsequent one; the increased risk returns with each pregnancy.
It’s an interesting observation, but I’m not sure what to make of it. It does not appear that women have a tendency to take more risks during pregnancy. Their use of tobacco and alcohol declines during pregnancy, indicating a conscious tendency to reduce risky behaviors wherever possible.
Fortunately, no one is suggesting that pregnant women shouldn’t drive. At their very worst, pregnant women still have fewer accidents than men of the same age!
Is it because pregnant women become distracted when the baby kicks? No, because the increased risk of an auto accident peaks in the fourth month of pregnancy, before the fetus is kicking. After the fourth month of pregnancy the risk declines each month until childbirth. And it doesn’t seem to matter whether it’s a first pregnancy or a subsequent one; the increased risk returns with each pregnancy.
It’s an interesting observation, but I’m not sure what to make of it. It does not appear that women have a tendency to take more risks during pregnancy. Their use of tobacco and alcohol declines during pregnancy, indicating a conscious tendency to reduce risky behaviors wherever possible.
Fortunately, no one is suggesting that pregnant women shouldn’t drive. At their very worst, pregnant women still have fewer accidents than men of the same age!
Topics:
development and aging,
sensory mechanisms
Friday, May 30, 2014
A DNA-based HPV Test for Screening for Cervical Cancer
Last month the FDA approved a DNA-based genetic test for the presence of human papilloma virus (HPV) as a first-choice screening option for cervical cancer. The DNA-based HPV test takes advantage of the fact that nearly all cases of cervical cancer are caused by HPV infections. The FDA’s decision means that women (and their doctors) can now choose the DNA-based test for the HPV virus over the traditional Pap test for screening for cervical cancer, if they wish.
Just because the FDA approved the test doesn’t mean that doctors are required to switch to it, though. It just means that it’s available as another option. The Pap test has been the gold standard for screening for cervical cancer for fifty years, whereas the DNA-based HPV test has only been around for about 10 years. Millions of women routinely get a pap test (or smear) every three to five years; many of them may be reluctant to switch. On the other hand, some doctors will undoubtedly recommend both tests, just to cover all bases.
The DNA-based HPV test is likely to cost about twice as much as the traditional Pap test, but neither test is very expensive (under $100). At the moment there are no recommendations from professional medical societies regarding how often the new test should be done, and whether (or under what conditions) it has any advantage over the Pap test.
Regardless of which screening test is used, a positive result (possible cancer) is generally checked for accuracy by a biopsy before any treatment is undertaken.
For more on screening tests for cervical cancer, see a previous blog post titled "New Guidelines Advise Less Frequent Pap Tests."
Just because the FDA approved the test doesn’t mean that doctors are required to switch to it, though. It just means that it’s available as another option. The Pap test has been the gold standard for screening for cervical cancer for fifty years, whereas the DNA-based HPV test has only been around for about 10 years. Millions of women routinely get a pap test (or smear) every three to five years; many of them may be reluctant to switch. On the other hand, some doctors will undoubtedly recommend both tests, just to cover all bases.
The DNA-based HPV test is likely to cost about twice as much as the traditional Pap test, but neither test is very expensive (under $100). At the moment there are no recommendations from professional medical societies regarding how often the new test should be done, and whether (or under what conditions) it has any advantage over the Pap test.
Regardless of which screening test is used, a positive result (possible cancer) is generally checked for accuracy by a biopsy before any treatment is undertaken.
For more on screening tests for cervical cancer, see a previous blog post titled "New Guidelines Advise Less Frequent Pap Tests."
Wednesday, May 21, 2014
A Sperm Donor’s Child Custody Battle
Does a sperm donor have any parental rights? Can he be held financially responsible for supporting the child? Sperm donors, and persons who use donated sperm for in vitro fertilization procedures should consider the ramifications carefully before deciding how to proceed.
An anonymous sperm donor who donates to an anonymous recipient through a registered sperm bank usually signs away all rights and is absolved of any future responsibilities. However, if the sperm donor and recipient are in a relationship, or even if they just know each other, what is agreed to beforehand can make a big difference. A lack of an agreement could spell trouble.
Consider the case of actor Jason Patric. Four years ago he donated sperm to an ex-girlfriend for an in vitro fertilization procedure (they had been unable to conceive during their relationship). After the baby boy was born he and his ex-girlfriend remained on friendly terms, and he contributed financially and spent time with the boy. But then the relationship soured. Now she wants sole custody. She claims that Mr. Patric never intended to be an equal parent, and that he only agreed to donate his sperm on the condition that he not be held responsible. She points out that his name does not appear on the child’s birth certificate. Mr. Patric is suing for shared custody of the boy in the state of California. He claims that he has been part of the boy’s life from the beginning and that he intended to be a parent to the child when he donated his sperm.
However this case turns out, it's a cautionary tale for anyone who is not married to the other biological parent of their biological child. Make sure you have a legally binding agreement describing your rights and responsibilities (if any). It wouldn’t hurt to know laws of the your state of residence as well.
An anonymous sperm donor who donates to an anonymous recipient through a registered sperm bank usually signs away all rights and is absolved of any future responsibilities. However, if the sperm donor and recipient are in a relationship, or even if they just know each other, what is agreed to beforehand can make a big difference. A lack of an agreement could spell trouble.
Consider the case of actor Jason Patric. Four years ago he donated sperm to an ex-girlfriend for an in vitro fertilization procedure (they had been unable to conceive during their relationship). After the baby boy was born he and his ex-girlfriend remained on friendly terms, and he contributed financially and spent time with the boy. But then the relationship soured. Now she wants sole custody. She claims that Mr. Patric never intended to be an equal parent, and that he only agreed to donate his sperm on the condition that he not be held responsible. She points out that his name does not appear on the child’s birth certificate. Mr. Patric is suing for shared custody of the boy in the state of California. He claims that he has been part of the boy’s life from the beginning and that he intended to be a parent to the child when he donated his sperm.
However this case turns out, it's a cautionary tale for anyone who is not married to the other biological parent of their biological child. Make sure you have a legally binding agreement describing your rights and responsibilities (if any). It wouldn’t hurt to know laws of the your state of residence as well.
Monday, May 19, 2014
First Case of MERS Transmission Within the U.S.
According to the Centers for Disease Control and Prevention (CDC), an Illinois man has contracted the Middle East respiratory syndrome (MERS) virus in this country. There are now three confirmed cases of MERS virus in the U.S. The other two patients had traveled to or lived in Saudi Arabia. It is presumed that they picked up the virus there. The Illinois man met with the first MERS patient several times in the U.S. before the patient knew he was carrying the virus, and shook hands with him. He did not become particularly ill and did not require medical treatment.
MERS first appeared in humans in Saudi Arabia about two years ago. Scientists believe that it may have made the jump to humans from camels. It is a virus in the coronavirus family, making it a close relative of the common cold and of the SARS (sudden acute respiratory syndrome) virus that caused nearly 800 deaths a decade ago. Symptoms of MERS are similar to those of the common cold or flu, except that it can lead to pneumonia, kidney failure, and even death. Nearly 30% of the approximately 700 confirmed cases of MERS infection (most of them in the Middle East) have died. Transmission between humans seems to require close contact; most of the cases involve health care workers or relatives of infected patients.
A virus found in only three people in the U.S. hardly seems worth mentioning. Nevertheless, MERS is being watched closely because it is fairly deadly and because if it ever mutates to become easily transmissible (by casual contact, such as riding in the same bus), a major pandemic could ensue. For now, though, officials stress that the public is not at risk.
MERS first appeared in humans in Saudi Arabia about two years ago. Scientists believe that it may have made the jump to humans from camels. It is a virus in the coronavirus family, making it a close relative of the common cold and of the SARS (sudden acute respiratory syndrome) virus that caused nearly 800 deaths a decade ago. Symptoms of MERS are similar to those of the common cold or flu, except that it can lead to pneumonia, kidney failure, and even death. Nearly 30% of the approximately 700 confirmed cases of MERS infection (most of them in the Middle East) have died. Transmission between humans seems to require close contact; most of the cases involve health care workers or relatives of infected patients.
A virus found in only three people in the U.S. hardly seems worth mentioning. Nevertheless, MERS is being watched closely because it is fairly deadly and because if it ever mutates to become easily transmissible (by casual contact, such as riding in the same bus), a major pandemic could ensue. For now, though, officials stress that the public is not at risk.
Thursday, May 8, 2014
A Compounding Pharmacy Goes Bankrupt
New England Pharmacy Center, the compounding pharmacy responsible for preparing contaminated medications that ultimately sickened over 700 people in 20 states and caused 64 deaths (this blog Oct, 9, 2012) has gone into bankruptcy. According to a New York Times report, the bankruptcy settlement establishes a fund of approximately $100 million that will be used to compensate victims and their relatives.
This closes the book on a tragic accident that didn’t need to happen. As a result of this case, it came to light that many of today’s compounding pharmacies prepare medications for wide distribution to hospitals and doctors across state lines, while the regulation of pharmacies falls to the individual states’ pharmacy boards. There have been calls for national oversight of compounding pharmacies by the Food and Drug Administration (FDA), but so far the oversight is essentially voluntary (this blog Oct. 16, 2013).
We’ll hope there is not another tragic event in the future. Unfortunately, that may be what it takes before there is a stronger outcry for serious national oversight of compounding pharmacies that sell across state lines.
This closes the book on a tragic accident that didn’t need to happen. As a result of this case, it came to light that many of today’s compounding pharmacies prepare medications for wide distribution to hospitals and doctors across state lines, while the regulation of pharmacies falls to the individual states’ pharmacy boards. There have been calls for national oversight of compounding pharmacies by the Food and Drug Administration (FDA), but so far the oversight is essentially voluntary (this blog Oct. 16, 2013).
We’ll hope there is not another tragic event in the future. Unfortunately, that may be what it takes before there is a stronger outcry for serious national oversight of compounding pharmacies that sell across state lines.
Tuesday, May 6, 2014
WHO Report on Antimicrobial Resistance
A good source of current information on microbial resistance to antibiotics is the new World Health Organization (WHO) report entitled “Antimicrobial Resistance: Global Report on Surveillance 2014”. You can download a 7-page summary and/or the entire 257-page report.
The report paints a fairly gloomy picture of where we stand right now with respect to resistance to antibiotics. High rates of resistance to antibiotics are now found in common disease-causing bacteria in all regions of the world. To make matters worse, there are gaps in information gathering and surveillance that make it difficult to know the full extent of the problem. According to the summary, “The problem is so serious that it threatens the achievements of modern medicine.” The report warns that in this century we may return to an era similar to before antibiotics, when even simple infections and minor injuries routinely killed people.
The report concludes that improved surveillance is needed, and that governments will have to take action if we expect the situation to get any better. No surprise there. WHO is responsible for overseeing worldwide disease surveillance for the United Nations, but neither it nor the United Nations is empowered to take the kinds of specific actions that governments can take, such as passing laws to prevent antibiotic over-use or spending more money on antibiotic research. It’ll be interesting to see if anything comes of this report.
The report paints a fairly gloomy picture of where we stand right now with respect to resistance to antibiotics. High rates of resistance to antibiotics are now found in common disease-causing bacteria in all regions of the world. To make matters worse, there are gaps in information gathering and surveillance that make it difficult to know the full extent of the problem. According to the summary, “The problem is so serious that it threatens the achievements of modern medicine.” The report warns that in this century we may return to an era similar to before antibiotics, when even simple infections and minor injuries routinely killed people.
The report concludes that improved surveillance is needed, and that governments will have to take action if we expect the situation to get any better. No surprise there. WHO is responsible for overseeing worldwide disease surveillance for the United Nations, but neither it nor the United Nations is empowered to take the kinds of specific actions that governments can take, such as passing laws to prevent antibiotic over-use or spending more money on antibiotic research. It’ll be interesting to see if anything comes of this report.
Friday, May 2, 2014
Advanced Biofuels Production Targets Reduced
Most of the ethanol used in blended gasoline is produced from corn. Only about 15% is “advanced biofuels” - ethanol made from various types of non-food biomass such as cornstalks and corncobs, wheat stalks, wood chips, and the pulp waste from fruit processing.
Under the Energy Independence and Security Act of 2007 (EISA 2007), the EPA establishes specific production targets each year for corn ethanol and advanced biofuels. The EPA recently proposed reducing the production targets for 2014. A large proportion of the proposed reduction will come at the expense of advanced biofuels. Back in 2007, EISA set a target for advanced biofuel production of 21 billion gallons by 2022. With a proposed 2014 production rate of only 2.2 billion gallons, that target looks like a pipe dream now.
Why is the EPA reducing its targets for advanced biofuels? A steady supply of corn ethanol is one reason. In addition, gasoline manufacturers (and even the publics) general dislike the mandate that ethanol be blended with gasoline. The original proposal was that gasoline should eventually contain 15% ethanol, but resistance to the higher level means that most gasoline still only contains 10% ethanol. With corn alcohol production high and fuel alcohol demand low, advanced biofuels aren’t really needed right now.
The new proposed production targets may create difficulties for several companies doing research into advanced biofuels, as well as those companies currently building production facilities. That’s too bad, because in the long run it would be nice to be able to produce ethanol economically from something other than a food source (corn).
Under the Energy Independence and Security Act of 2007 (EISA 2007), the EPA establishes specific production targets each year for corn ethanol and advanced biofuels. The EPA recently proposed reducing the production targets for 2014. A large proportion of the proposed reduction will come at the expense of advanced biofuels. Back in 2007, EISA set a target for advanced biofuel production of 21 billion gallons by 2022. With a proposed 2014 production rate of only 2.2 billion gallons, that target looks like a pipe dream now.
Why is the EPA reducing its targets for advanced biofuels? A steady supply of corn ethanol is one reason. In addition, gasoline manufacturers (and even the publics) general dislike the mandate that ethanol be blended with gasoline. The original proposal was that gasoline should eventually contain 15% ethanol, but resistance to the higher level means that most gasoline still only contains 10% ethanol. With corn alcohol production high and fuel alcohol demand low, advanced biofuels aren’t really needed right now.
The new proposed production targets may create difficulties for several companies doing research into advanced biofuels, as well as those companies currently building production facilities. That’s too bad, because in the long run it would be nice to be able to produce ethanol economically from something other than a food source (corn).
Wednesday, April 30, 2014
Powdered Alcohol? Not Quite Yet…
You’ve all heard the joke about powdered water (“Just add water and stir”). But did you know that someone has actually managed to create a powdered alcohol product? It’s called Palcohol. Just add it to water and presto, you have an alcoholic beverage.
Last week it was reported that the U.S. Alcohol and Tobacco Tax and Trade Bureau had approved Palcohol. In truth, the bureau’s only role is to approve the packaging and labeling of alcoholic products. The choice of whether or not to allow the sale of alcoholic products is up to the individual states. After the story broke and people began expressing their opinions about the product, the bureau said that its approval of the product packaging had been “issued in error”. Final packaging approval is on hold for now. And whether any states will eventually approve Palcohol for sale is anybody’s guess.
Folks have come up with all sorts of imaginative ideas (both and good and bad) for how powdered alcohol could be used or abused. Not everyone is convinced that this product should ever reach store shelves. What do you think? Would you use it, and if so, how?
Last week it was reported that the U.S. Alcohol and Tobacco Tax and Trade Bureau had approved Palcohol. In truth, the bureau’s only role is to approve the packaging and labeling of alcoholic products. The choice of whether or not to allow the sale of alcoholic products is up to the individual states. After the story broke and people began expressing their opinions about the product, the bureau said that its approval of the product packaging had been “issued in error”. Final packaging approval is on hold for now. And whether any states will eventually approve Palcohol for sale is anybody’s guess.
Folks have come up with all sorts of imaginative ideas (both and good and bad) for how powdered alcohol could be used or abused. Not everyone is convinced that this product should ever reach store shelves. What do you think? Would you use it, and if so, how?
Topics:
dietary supplements,
science and society
Monday, April 21, 2014
Problems with Herbal Supplements
A study by Canadian researchers provides the best evidence yet that many herbal supplement products may not be what they seem.
Using DNA analysis, the researchers first developed a DNA “barcode” library of over 100 different species of plants commonly used in herbal remedies. Then they compared the DNA barcodes of the herbal plant ingredients in 44 different herbal supplement products from 12 manufacturers against the barcode library. All of the tested products are currently available in the U.S. and Canada.
The results were, in a word, shocking. Only about half of the supplement products tested were “authentic”, meaning that the plant species listed on the product label was present in the product. However, that did not mean that the product was pure; a third of these authentic products contained contaminants and/or fillers such as rice, wheat or alfalfa. Of the 44 products tested, fully a third were complete fakes; they contained none of the herb listed on the label.
How about the quality of the different supplement manufacturers? The number of samples tested was small (only 44 products tested from 12 companies) so statistical analysis isn’t possible. Nevertheless, the researchers report that only two companies’ products were all authentic and free of contaminants or fillers. At the other end of the scale, the tested products of three companies were all complete fakes. The researchers did not provide the names of the companies, but wouldn’t we like to know?!
It’s “buyer’s beware” when it comes to herbal supplements. Take them at your own risk.
Using DNA analysis, the researchers first developed a DNA “barcode” library of over 100 different species of plants commonly used in herbal remedies. Then they compared the DNA barcodes of the herbal plant ingredients in 44 different herbal supplement products from 12 manufacturers against the barcode library. All of the tested products are currently available in the U.S. and Canada.
The results were, in a word, shocking. Only about half of the supplement products tested were “authentic”, meaning that the plant species listed on the product label was present in the product. However, that did not mean that the product was pure; a third of these authentic products contained contaminants and/or fillers such as rice, wheat or alfalfa. Of the 44 products tested, fully a third were complete fakes; they contained none of the herb listed on the label.
How about the quality of the different supplement manufacturers? The number of samples tested was small (only 44 products tested from 12 companies) so statistical analysis isn’t possible. Nevertheless, the researchers report that only two companies’ products were all authentic and free of contaminants or fillers. At the other end of the scale, the tested products of three companies were all complete fakes. The researchers did not provide the names of the companies, but wouldn’t we like to know?!
It’s “buyer’s beware” when it comes to herbal supplements. Take them at your own risk.
Thursday, April 17, 2014
GINA Doesn’t Protect Against Genetic Discrimination
The costs of having your DNA analyzed for known genetic diseases has plummeted in recent years – to under $1,000. That is good news for those who might want their DNA analyzed. But some people have avoided being tested out of privacy concerns.
To protect the privacy of your genetic information, in 2008 Congress passed the Genetic Information Nondiscrimination Act (GINA). GINA stipulates that employers and health care providers cannot seek the results of genetic testing, and cannot discriminate on the basis of genetic information. It sounds good, right?
Wrong! It turns out that GINA does not apply to life, disability, or long-term care insurers! If you apply for life insurance after having your DNA tested, the insurance company can require you to answer truthfully (“Have you had your DNA tested?”) and then compel you to provide the results of your DNA test before deciding whether or not to insure you. And if your genetic profile indicates that you might be at risk for a specific genetic disease, you might find yourself uninsurable even though you are currently healthy.
I was surprised to learn that congressional sponsors of GINA were aware of this when GINA was passed in 2008. Apparently, it took more than a decade to get GINA approved by Congress. My guess is that there was intense opposition to GINA from the insurance industry. In the end, the bill’s sponsors had to settle for just part of what they wanted (non-discrimination in health insurance and employment), and give up on the rest.
Truthfully? GINA doesn’t fully live up to its name. And that’s unfortunate.
To protect the privacy of your genetic information, in 2008 Congress passed the Genetic Information Nondiscrimination Act (GINA). GINA stipulates that employers and health care providers cannot seek the results of genetic testing, and cannot discriminate on the basis of genetic information. It sounds good, right?
Wrong! It turns out that GINA does not apply to life, disability, or long-term care insurers! If you apply for life insurance after having your DNA tested, the insurance company can require you to answer truthfully (“Have you had your DNA tested?”) and then compel you to provide the results of your DNA test before deciding whether or not to insure you. And if your genetic profile indicates that you might be at risk for a specific genetic disease, you might find yourself uninsurable even though you are currently healthy.
I was surprised to learn that congressional sponsors of GINA were aware of this when GINA was passed in 2008. Apparently, it took more than a decade to get GINA approved by Congress. My guess is that there was intense opposition to GINA from the insurance industry. In the end, the bill’s sponsors had to settle for just part of what they wanted (non-discrimination in health insurance and employment), and give up on the rest.
Truthfully? GINA doesn’t fully live up to its name. And that’s unfortunate.
Topics:
genetic testing,
genetics and inheritance
Tuesday, April 15, 2014
A Blood Test for Concussions
A Swedish team of researchers has developed a blood test to help determine who might have suffered a concussion. The new test measures the amount of two specific proteins in the blood; a nerve cell protein called tau, and a protein called “S-100 calcium-binding protein B”, found in neuroglial supporting cells in the brain called astrocytes.
In developing and validating the test, the researchers took blood samples from 47 Swedish professional hockey players before the hockey season began, to establish baseline values of the two proteins. During the 2012-2013 Swedish hockey season 35 of the 288 hockey players who had agreed ahead of time to participate in the study suffered concussions. Blood samples were taken from the injured players at 1, 12, 36, and 144 hours after concussive injury. In these 35 players, the blood levels of both proteins rose within the first hour after the injury to approximately twice the baseline values. Both markers fell toward baseline in subsequent samples.
Together, the data suggest that elevated levels of these two markers an hour after a possible injury are a sign that a concussive injury has indeed occurred.
The new test could become part of the normal procedure for diagnosing head injuries in sports. If it could be packaged in a simple-to-use kit form, it may also help sports physicians and coaches decide whether a player should be allowed to return to play in the late stages of a game, or instead, sent for further medical diagnosis and treatment.
For more on the subject of diagnosing concussions, go to a previous blog post titled "Measuring the Severity of Head Impacts in Sports."
In developing and validating the test, the researchers took blood samples from 47 Swedish professional hockey players before the hockey season began, to establish baseline values of the two proteins. During the 2012-2013 Swedish hockey season 35 of the 288 hockey players who had agreed ahead of time to participate in the study suffered concussions. Blood samples were taken from the injured players at 1, 12, 36, and 144 hours after concussive injury. In these 35 players, the blood levels of both proteins rose within the first hour after the injury to approximately twice the baseline values. Both markers fell toward baseline in subsequent samples.
Together, the data suggest that elevated levels of these two markers an hour after a possible injury are a sign that a concussive injury has indeed occurred.
The new test could become part of the normal procedure for diagnosing head injuries in sports. If it could be packaged in a simple-to-use kit form, it may also help sports physicians and coaches decide whether a player should be allowed to return to play in the late stages of a game, or instead, sent for further medical diagnosis and treatment.
For more on the subject of diagnosing concussions, go to a previous blog post titled "Measuring the Severity of Head Impacts in Sports."
Monday, April 7, 2014
Omega-3 Fatty Acids Don’t Protect Against Heart Disease?
Do an Internet search on “omega-3 fatty acids” and you’ll find that omega-3s, as they are called, are a type of polyunsaturated fat. They’re a minor component of cell membranes and they have effects in blood clotting. And since your body doesn’t make them, some omega-3s in your diet are considered essential to good health. Eating fatty fish (such as sardines or salmon), nuts, or certain plant oils (canola or soybean oil) occasionally should be sufficient.
Dig a little deeper and you’ll undoubtedly read that omega-3s protect against heart disease and stroke. That claim has spawned a huge omega-3 supplements industry, which encourages you to take an omega-3 supplement pill every day to ward off heart disease. This claim is often backed by at least one research study to support the claim. But is it true?
A recent meta-analysis* of the role of various fats in cardiovascular disease questions the cardiovascular protective effect of omega-3s. To understand why this particular analysis is so important, you need to know what a “meta-analysis” is. Basically, a meta-analysis is a study of many previous studies. In a meta-analysis, each previous study is a single data point. That makes meta-analysis an exceedingly powerful tool to tease out small effects, when one paper may say one thing and another says something quite different.
This particular meta-analysis examined 72 previous research studies, involving over 500,000 people overall. Some of the studies were observational, meaning that they examined the relationship between measured specific fatty acid biomarkers and heart disease risk. Others studies were randomized, controlled experiments of fatty acid supplementation. Overall, there was not a statistically lower risk of cardiovascular disease among participants in the high omega-3 groups, in either kind of study.
Bottom line: You probably get enough of the minimum amounts of omega-3s required for good health in your normal diet. I, for one, won’t be taking an omega-3 pill every day just to avoid heart disease. (For those of you will still choose to take omega-3s “just to be sure”, rest easy; there was no evidence presented in this meta-study that they harm you, either.)
* The complete manuscript is only available by subscription.
Dig a little deeper and you’ll undoubtedly read that omega-3s protect against heart disease and stroke. That claim has spawned a huge omega-3 supplements industry, which encourages you to take an omega-3 supplement pill every day to ward off heart disease. This claim is often backed by at least one research study to support the claim. But is it true?
A recent meta-analysis* of the role of various fats in cardiovascular disease questions the cardiovascular protective effect of omega-3s. To understand why this particular analysis is so important, you need to know what a “meta-analysis” is. Basically, a meta-analysis is a study of many previous studies. In a meta-analysis, each previous study is a single data point. That makes meta-analysis an exceedingly powerful tool to tease out small effects, when one paper may say one thing and another says something quite different.
This particular meta-analysis examined 72 previous research studies, involving over 500,000 people overall. Some of the studies were observational, meaning that they examined the relationship between measured specific fatty acid biomarkers and heart disease risk. Others studies were randomized, controlled experiments of fatty acid supplementation. Overall, there was not a statistically lower risk of cardiovascular disease among participants in the high omega-3 groups, in either kind of study.
Bottom line: You probably get enough of the minimum amounts of omega-3s required for good health in your normal diet. I, for one, won’t be taking an omega-3 pill every day just to avoid heart disease. (For those of you will still choose to take omega-3s “just to be sure”, rest easy; there was no evidence presented in this meta-study that they harm you, either.)
* The complete manuscript is only available by subscription.
Friday, April 4, 2014
Stem Cell Paper Challenged
Two months ago I reported on an exciting new finding (this blog Feb. 3, 2014) that a Japanese and American team of researchers had developed a simple way to produce pluripotent stem cells from adult cells. The paper was hailed as a breakthrough of sorts. If true, it suggested that deriving stem cells from embryos (always controversial) might no longer be necessary.
That finding is now in serious doubt, because other researchers have been unable to verify the data. A blog site that is following attempts to duplicate the research says that most researchers no longer believe that the findings are real (search STAP cells). The research institute where the Japanese researchers work is investigating. So far the original paper has not been retracted, but that’s a distinct possibility.
How can we have any faith in scientific discoveries if the story changes month-to-month? The answer is that science is not about having faith. It’s about verifying and then verifying again, until we can have confidence, backed by reproducible data, in what we know. It’s messy. Sometimes the answer isn’t what we thought it was, but over time we get closer and closer to the truth, whatever it is.
As for pluripotent stem cells, it’s back to square one when it comes to creating them from adult cells, apparently. Embryos may yet be needed for awhile.
That finding is now in serious doubt, because other researchers have been unable to verify the data. A blog site that is following attempts to duplicate the research says that most researchers no longer believe that the findings are real (search STAP cells). The research institute where the Japanese researchers work is investigating. So far the original paper has not been retracted, but that’s a distinct possibility.
How can we have any faith in scientific discoveries if the story changes month-to-month? The answer is that science is not about having faith. It’s about verifying and then verifying again, until we can have confidence, backed by reproducible data, in what we know. It’s messy. Sometimes the answer isn’t what we thought it was, but over time we get closer and closer to the truth, whatever it is.
As for pluripotent stem cells, it’s back to square one when it comes to creating them from adult cells, apparently. Embryos may yet be needed for awhile.
Tuesday, April 1, 2014
Arizona Restricts the Use of Mifeprex (RU-486)
New rules take effect in Arizona today that limit the use of the abortion pill, RU-486. The new rules restrict the use of RU-486 to within the first seven weeks of pregnancy, and only in the doses approved by the FDA back in 2000. In addition, both doses of the drug (two are required) must be administered in a health clinic. The new rules make Arizona one of the most restrictive states in the nation regarding the use of RU-486.
The rules were announced in January, but implementation was delayed by a lawsuit filed by Planned Parenthood. Yesterday a U.S. District judge refused to grant an injunction against the rules, opening the way for them to take effect today.
Most states permit the use of RU-486 (when used in combination with a synthetic progesterone) up to nine weeks after pregnancy. The combination of the two drugs has been shown to be effective for two weeks longer than RU-486 alone, and it’s considered safer because a lower dose of RU-486 is needed. In addition, the combination drug can be taken at home.
Why did women’s health advocates fight the rules? It’s not just that two weeks are being cut off the available treatment window for a chemical abortion. More importantly, the rules restrict the use of RU-486 to a treatment regimen which is rarely used these days because it is no longer considered the most safe and effective by physicians.
Apparently that doesn’t matter in Arizona. The state has a history of proposing abortion-unfriendly legislation.
The rules were announced in January, but implementation was delayed by a lawsuit filed by Planned Parenthood. Yesterday a U.S. District judge refused to grant an injunction against the rules, opening the way for them to take effect today.
Most states permit the use of RU-486 (when used in combination with a synthetic progesterone) up to nine weeks after pregnancy. The combination of the two drugs has been shown to be effective for two weeks longer than RU-486 alone, and it’s considered safer because a lower dose of RU-486 is needed. In addition, the combination drug can be taken at home.
Why did women’s health advocates fight the rules? It’s not just that two weeks are being cut off the available treatment window for a chemical abortion. More importantly, the rules restrict the use of RU-486 to a treatment regimen which is rarely used these days because it is no longer considered the most safe and effective by physicians.
Apparently that doesn’t matter in Arizona. The state has a history of proposing abortion-unfriendly legislation.
Friday, March 28, 2014
Measuring the Severity of Head Impacts in Sports
It’s well known that repeated high-impact collisions in sports can cause acute concussive brain injury and even permanent brain damage. Unfortunately, there aren’t any simple quantitative tests to determine precisely who has suffered too many high-impact blows to the head. How severe does an impact have to be to cause injury? And how many moderate impacts are too many?
Devices designed to measure the relative severity and direction of head impacts may soon yield some answers. Already, at least one commercial product is available. The Checklight by Reebok is a relatively inexpensive monitoring device embedded into a skullcap that can be worn under a helmet. The Checklight combines a series of three accelerometers (to measure g-forces) with a gyroscope (to measure direction). A mathematical algorithm crunches the numbers and comes up with a relative measure of impact intensity. A green light on the device turns to yellow after a moderate impact and red after a more severe one.
But what do the indicator lights really mean? Reebok is careful not to call the Checklight a device for determining who has actually suffered a concussive blow to the head. They call it a “conversation starter”, meaning that it may allow coaches and medical personnel to decide who might need to be evaluated carefully by a medical professional. There is general agreement that more research is needed before these types of devices could be used to truly define who has suffered a concussion.
Some people worry that the device might lead to a false sense of complacency if too much reliance is placed on it. Others argue that we should be looking for ways to reduce the number and severity of head impacts in sports, instead of looking for better ways to determine who might be at risk of a concussion so that we can bench them. Still, it’s encouraging to see research-and-development efforts like this one being undertaken. There’s no reason we can’t take both approaches at once.
The Checklight is meant to be worn under a helmet. Researchers are working on similar impact-measuring devices that can be incorporated into a headband, for use in sports that don’t use helmets.
For more on this subject, go to a previous blog post titled "Diagnosing Concussions in Athletes Quickly and Inexpensively."
Devices designed to measure the relative severity and direction of head impacts may soon yield some answers. Already, at least one commercial product is available. The Checklight by Reebok is a relatively inexpensive monitoring device embedded into a skullcap that can be worn under a helmet. The Checklight combines a series of three accelerometers (to measure g-forces) with a gyroscope (to measure direction). A mathematical algorithm crunches the numbers and comes up with a relative measure of impact intensity. A green light on the device turns to yellow after a moderate impact and red after a more severe one.
But what do the indicator lights really mean? Reebok is careful not to call the Checklight a device for determining who has actually suffered a concussive blow to the head. They call it a “conversation starter”, meaning that it may allow coaches and medical personnel to decide who might need to be evaluated carefully by a medical professional. There is general agreement that more research is needed before these types of devices could be used to truly define who has suffered a concussion.
Some people worry that the device might lead to a false sense of complacency if too much reliance is placed on it. Others argue that we should be looking for ways to reduce the number and severity of head impacts in sports, instead of looking for better ways to determine who might be at risk of a concussion so that we can bench them. Still, it’s encouraging to see research-and-development efforts like this one being undertaken. There’s no reason we can’t take both approaches at once.
The Checklight is meant to be worn under a helmet. Researchers are working on similar impact-measuring devices that can be incorporated into a headband, for use in sports that don’t use helmets.
For more on this subject, go to a previous blog post titled "Diagnosing Concussions in Athletes Quickly and Inexpensively."
Sunday, March 23, 2014
A Blood Test to Predict Alzheimer’s Disease
The news media made a big deal this month of the finding that a blood test has been developed that can predict (with 90% accuracy in persons over 70 years of age) who will develop Alzheimer’s disease within the next two to three years. A representative news article is this one, by NPR.
The development of a blood test to predict who is likely to develop Alzheimer’s disease sounds like a major breakthrough until you realize that at the moment there is no way to prevent Alzheimer’s from developing, and no cure once you have it. That raises an interesting dilemma; if you’re not going to benefit from being tested (prevention or cure), why be tested? Would you want to know you’re going to develop Alzheimer’s if there was nothing you could do about it except get your affairs in order?
One other fact to consider: there’s no evidence that the test can predict 40, 20, or even 10 years in advance who will get Alzheimer’s disease. The test has only been proven to be accurate within 2-3 years of the onset of Alzheimer’s. You’d have to get the test every year just to know that you were about to develop Alzheimer’s very soon. What would be the total cost of a test every year for a lifetime? The biggest beneficiaries would be your doctor and the blood-testing company.
The new test will certainly benefit researchers searching for ways to prevent Alzheimer’s, though. That’s because it will allow researchers to test potential preventative measures on people who are almost certain to get Alzheimer’s disease (as determined by the test) before the disease actually develops. That is, provided that people are willing to be tested and then to join a research study if they test positive.
The development of a blood test to predict who is likely to develop Alzheimer’s disease sounds like a major breakthrough until you realize that at the moment there is no way to prevent Alzheimer’s from developing, and no cure once you have it. That raises an interesting dilemma; if you’re not going to benefit from being tested (prevention or cure), why be tested? Would you want to know you’re going to develop Alzheimer’s if there was nothing you could do about it except get your affairs in order?
One other fact to consider: there’s no evidence that the test can predict 40, 20, or even 10 years in advance who will get Alzheimer’s disease. The test has only been proven to be accurate within 2-3 years of the onset of Alzheimer’s. You’d have to get the test every year just to know that you were about to develop Alzheimer’s very soon. What would be the total cost of a test every year for a lifetime? The biggest beneficiaries would be your doctor and the blood-testing company.
The new test will certainly benefit researchers searching for ways to prevent Alzheimer’s, though. That’s because it will allow researchers to test potential preventative measures on people who are almost certain to get Alzheimer’s disease (as determined by the test) before the disease actually develops. That is, provided that people are willing to be tested and then to join a research study if they test positive.
Tuesday, March 18, 2014
Economic Theory is Applied to Kidney Donations
In 2012 the Nobel prize in economics was awarded to economist Alvin Roth and mathematician Lloyd Shapley, for their work in developing algorithms for efficient computerized matching of individuals with unique needs with other similar individuals or institutions. Their algorithms have been used to match employers with employees; hospitals with doctors seeking residencies; students with schools; even kidney donors with kidney recipients.
That’s right; kidneys. Matching donors to recipients is not all that easy, because although a donor may want to donate to a specific recipient (say a relative, or a spouse), often they can’t because the tissue match is not good enough. That’s where Dr. Roth and his computer algorithm come in. By entering all available potential donors and recipients into a computer file and then applying a matching algorithm based on each donor and recipient’s tissue type, the best possible match can be found for each donor and for each recipient, even though they might not even be aware of each other. The donor may end up donating to an unknown and unrelated recipient, but in exchange the recipient will get a kidney from another, also unrelated, donor. The effect is the same as if the donor had donated directly to his/her specific recipient of choice!
Dr. Roth’s matching algorithm was first applied to kidney donations back in 2004 by the New England Program for Kidney Exchange (NEPKE). The method worked so well that NEPKE was later folded into the current national kidney matching system, United Network for Organ Sharing (UNOS). Since 2004 Dr. Roth’s method of matching has resulted in over 2,000 kidney donations, most of them between unrelated donors and recipients.
That’s right; kidneys. Matching donors to recipients is not all that easy, because although a donor may want to donate to a specific recipient (say a relative, or a spouse), often they can’t because the tissue match is not good enough. That’s where Dr. Roth and his computer algorithm come in. By entering all available potential donors and recipients into a computer file and then applying a matching algorithm based on each donor and recipient’s tissue type, the best possible match can be found for each donor and for each recipient, even though they might not even be aware of each other. The donor may end up donating to an unknown and unrelated recipient, but in exchange the recipient will get a kidney from another, also unrelated, donor. The effect is the same as if the donor had donated directly to his/her specific recipient of choice!
Dr. Roth’s matching algorithm was first applied to kidney donations back in 2004 by the New England Program for Kidney Exchange (NEPKE). The method worked so well that NEPKE was later folded into the current national kidney matching system, United Network for Organ Sharing (UNOS). Since 2004 Dr. Roth’s method of matching has resulted in over 2,000 kidney donations, most of them between unrelated donors and recipients.
Thursday, March 13, 2014
A Skin Patch to Deliver the Flu Vaccine
What if you could get the flu vaccine in the form of a small patch that you could apply on your own, without having to go to a health professional? Perhaps you could even buy the flu patch over the Internet and have it mailed to your home!
That future may not be that far off, according to researchers at the Georgia Institute of Technology and Emory University. They’ve developed a small patch with 50 tiny dissolvable needles that penetrate into the deeper layers of the skin. The patch itself (without vaccine) has been tested extensively on human volunteers, according to an article in the April 1 issue of Vaccine (pp. 1856-1862). An abstract of the article can be viewed here.
Clinical trials with patches loaded with vaccine may begin as early as next year. Provided it works, the flu patch could become available within a couple more years. Think of it. No trip to a health facility for an annual flu shot. No needle and no muscle soreness later. Cheaper, more convenient, and less painful – what’s not to love about that?
That future may not be that far off, according to researchers at the Georgia Institute of Technology and Emory University. They’ve developed a small patch with 50 tiny dissolvable needles that penetrate into the deeper layers of the skin. The patch itself (without vaccine) has been tested extensively on human volunteers, according to an article in the April 1 issue of Vaccine (pp. 1856-1862). An abstract of the article can be viewed here.
Clinical trials with patches loaded with vaccine may begin as early as next year. Provided it works, the flu patch could become available within a couple more years. Think of it. No trip to a health facility for an annual flu shot. No needle and no muscle soreness later. Cheaper, more convenient, and less painful – what’s not to love about that?
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