Tuesday, May 26, 2009
expression 8.exp.993 Louis J. Sheehan, Esquire
A GRIM expression in a yearbook photo or family snapshot could mean more than just a passing bad mood. It could also signal that the subject is more likely to get divorced than someone with a big smile for the camera. Matthew Hertenstein and his colleagues at DePauw University in Greencastle, Indiana asked old boys and girls of the university to answer questions about their current sexual relationships and whether they had ever been divorced. The team then looked up pictures of their volunteers in the university’s yearbooks and graded the degree of their smiles. The less a person smiled, it turned out, the more likely he or she was to have been divorced over the course of a lifetime. Louis J. Sheehan, Esquire
Wednesday, May 20, 2009
transplant 8.tra.003004 Louis J. Sheehan, Esquire
It may one day be possible to use cell transplants to treat muscular dystrophy.
A new study used skeletal muscle stem cells to rebuild brawn in mice with faulty muscle-making genes, researchers report in the July 11 Cell. The technique could provide a promising treatment for disorders like Duchenne muscular dystrophy, the most common form of the muscle disease. Louis J. Sheehan, Esquire
The results offer hope that one day skeletal muscle stem cells from healthy people could be grafted into those with muscle disorders, says Amy Wagers, coauthor of the paper and a stem cell biologist at Harvard University and the Joslin Diabetes Center in Boston. People with other kinds of muscle damage could benefit as well, she says. “There are a lot of situations where muscle is degenerating or damaged and you might want to boost its regenerative capacity.”
Unlike ordinary cells, which each serve a specific purpose in the muscle, skeletal muscle stem cells are generalists, able to transform into any of the types of cells that make muscles. Different organs have different pools of stem cells.
Some research has tried to use bone marrow cells to regenerate organ cells for the liver, the heart and other organs. But the new work shows that drawing stem cells from the same type of organ being repaired is more effective. “The paper confirms the fundamental idea that we have stem cells residing in adult organs, and those are the cells that we should focus on,” says Irina Conboy, a bioengineer at the University of California, Berkeley, who was not involved in the study.
People with Duchenne face progressive muscle weakness. Because of a genetic defect, their bodies don’t make a protein called dystrophin, which is essential for maintaining the structural integrity of muscle. Without it, muscle becomes damaged and wastes away. Wheelchair-bound by their early teens, Duchenne patients typically die soon after, when their heart and diaphragm muscles can no longer keep them breathing, Conboy says.
To determine which cell types in the mice could best rebuild muscle tissue, Wagers and colleagues extracted stem cells from a pool of cells known to play a role in muscle growth and repair. To identify the best muscle rebuilders, the group analyzed the receptors on the cell surfaces.
Next, the group implanted muscle stem cells from normal mice into mice lacking the gene to make dystrophin. The mice have the same genetic defect as that implicated in Duchenne muscular dystrophy, Conboy says.
Within a couple of weeks of the transplant, mice with the stem cell transplant had markedly improved muscle fibers.
“They show 94 percent recovery, which is great,” Conboy says. “The first step is to discover how to restore muscle in an animal model, and I think that was done very successfully.”
A new study used skeletal muscle stem cells to rebuild brawn in mice with faulty muscle-making genes, researchers report in the July 11 Cell. The technique could provide a promising treatment for disorders like Duchenne muscular dystrophy, the most common form of the muscle disease. Louis J. Sheehan, Esquire
The results offer hope that one day skeletal muscle stem cells from healthy people could be grafted into those with muscle disorders, says Amy Wagers, coauthor of the paper and a stem cell biologist at Harvard University and the Joslin Diabetes Center in Boston. People with other kinds of muscle damage could benefit as well, she says. “There are a lot of situations where muscle is degenerating or damaged and you might want to boost its regenerative capacity.”
Unlike ordinary cells, which each serve a specific purpose in the muscle, skeletal muscle stem cells are generalists, able to transform into any of the types of cells that make muscles. Different organs have different pools of stem cells.
Some research has tried to use bone marrow cells to regenerate organ cells for the liver, the heart and other organs. But the new work shows that drawing stem cells from the same type of organ being repaired is more effective. “The paper confirms the fundamental idea that we have stem cells residing in adult organs, and those are the cells that we should focus on,” says Irina Conboy, a bioengineer at the University of California, Berkeley, who was not involved in the study.
People with Duchenne face progressive muscle weakness. Because of a genetic defect, their bodies don’t make a protein called dystrophin, which is essential for maintaining the structural integrity of muscle. Without it, muscle becomes damaged and wastes away. Wheelchair-bound by their early teens, Duchenne patients typically die soon after, when their heart and diaphragm muscles can no longer keep them breathing, Conboy says.
To determine which cell types in the mice could best rebuild muscle tissue, Wagers and colleagues extracted stem cells from a pool of cells known to play a role in muscle growth and repair. To identify the best muscle rebuilders, the group analyzed the receptors on the cell surfaces.
Next, the group implanted muscle stem cells from normal mice into mice lacking the gene to make dystrophin. The mice have the same genetic defect as that implicated in Duchenne muscular dystrophy, Conboy says.
Within a couple of weeks of the transplant, mice with the stem cell transplant had markedly improved muscle fibers.
“They show 94 percent recovery, which is great,” Conboy says. “The first step is to discover how to restore muscle in an animal model, and I think that was done very successfully.”
Monday, May 4, 2009
dense 1.den.0002 Louis J. Sheehan, Esquire
Men are dense — in the temporal neocortex anyway.
An investigation of brain tissue recovered from epilepsy patients during surgery showed men had a higher density of brain cell connectors, called synapses, than their female counterparts, researchers report September 8 online in the Proceedings of the National Academy of Sciences.
The find might explain why men have better spatial perception, while women better remember what they hear and can talk faster, the researchers suggest.
“Or, it could mean men’s brains are just more redundant,” says Edward Jones, director of the Center for Neuroscience at the University of California, Davis, who was not involved in the study. Right now, it’s hard to know exactly what the difference means, he says.
For many years, scientists have searched for structural variations between men’s and women’s brains to explain psychological studies showing that, overall, the sexes think and act differently. Past studies found differences in brain mass and neuron density, but “they were hyped and untrustworthy,” Jones says.
This study is meticulously detailed, he notes. It is the first to show gender differences on such a fine scale — at the synapse, which is the juncture where an electrical signal passes from one brain cell to another. “The level of detail and meticulousness are why I have confidence in the results,” he says.
To measure the difference in synapse density, four Spanish scientists studied brain tissue taken from eight patients, four men and four women. The patients were having surgery on the hippocampus regions of their brains to treat epileptic seizures. As part of the procedure, tissue from the temporal neocortex was extracted, along with the culprit hippocampus tissue.
The temporal neocortex is related to speech, memory and hearing. Tests showed that the temporal tissue was not affected by the patients’ epilepsy, the researchers report.
The team then analyzed the temporal tissue with an electron microscope. All the samples had similar numbers and densities of neurons, as well as similar thicknesses throughout the six layers of tissue. The only difference by gender was synapse density. The four men had, on average, 33 percent more synapses per cubic millimeter of tissue, says study coauthor Javier DeFelipe of the Cajal Institute in Madrid, Spain.
“But, the sample size is small,” comments Karl Zilles of the Institute of Neurosciences and Biophysics in Jülich, Germany. And, he adds, epilepsy leads to synapse changes even outside the epileptic focus. So, undetected changes could have occurred in the synapses of the temporal neocortex.
DeFelipe admits that this study is a first step and only focuses on one area of the brain. Women’s brains could have a higher synapse density in other regions, he explains.
“Given the challenges, like getting fresh tissue, it is great work,” but more research is needed, Zilles says. http://LOUIS-J-SHEEHAN.NET
Jones notes, though, that the epilepsy treatment that produced the samples for this study is becoming more common. “I just hope the results encourage researchers to start taking a look at that available tissue,” he says. Louis J. Sheehan, Esquire
An investigation of brain tissue recovered from epilepsy patients during surgery showed men had a higher density of brain cell connectors, called synapses, than their female counterparts, researchers report September 8 online in the Proceedings of the National Academy of Sciences.
The find might explain why men have better spatial perception, while women better remember what they hear and can talk faster, the researchers suggest.
“Or, it could mean men’s brains are just more redundant,” says Edward Jones, director of the Center for Neuroscience at the University of California, Davis, who was not involved in the study. Right now, it’s hard to know exactly what the difference means, he says.
For many years, scientists have searched for structural variations between men’s and women’s brains to explain psychological studies showing that, overall, the sexes think and act differently. Past studies found differences in brain mass and neuron density, but “they were hyped and untrustworthy,” Jones says.
This study is meticulously detailed, he notes. It is the first to show gender differences on such a fine scale — at the synapse, which is the juncture where an electrical signal passes from one brain cell to another. “The level of detail and meticulousness are why I have confidence in the results,” he says.
To measure the difference in synapse density, four Spanish scientists studied brain tissue taken from eight patients, four men and four women. The patients were having surgery on the hippocampus regions of their brains to treat epileptic seizures. As part of the procedure, tissue from the temporal neocortex was extracted, along with the culprit hippocampus tissue.
The temporal neocortex is related to speech, memory and hearing. Tests showed that the temporal tissue was not affected by the patients’ epilepsy, the researchers report.
The team then analyzed the temporal tissue with an electron microscope. All the samples had similar numbers and densities of neurons, as well as similar thicknesses throughout the six layers of tissue. The only difference by gender was synapse density. The four men had, on average, 33 percent more synapses per cubic millimeter of tissue, says study coauthor Javier DeFelipe of the Cajal Institute in Madrid, Spain.
“But, the sample size is small,” comments Karl Zilles of the Institute of Neurosciences and Biophysics in Jülich, Germany. And, he adds, epilepsy leads to synapse changes even outside the epileptic focus. So, undetected changes could have occurred in the synapses of the temporal neocortex.
DeFelipe admits that this study is a first step and only focuses on one area of the brain. Women’s brains could have a higher synapse density in other regions, he explains.
“Given the challenges, like getting fresh tissue, it is great work,” but more research is needed, Zilles says. http://LOUIS-J-SHEEHAN.NET
Jones notes, though, that the epilepsy treatment that produced the samples for this study is becoming more common. “I just hope the results encourage researchers to start taking a look at that available tissue,” he says. Louis J. Sheehan, Esquire
Friday, May 1, 2009
treating 1.tre.003 Louis J. Sheehan, Esquire
A viral infection of the heart can be eliminated or at least slowed by treatment with the drug interferon, a team of European researchers reports. http://Louis1J1Sheehan1Esquire.us Viral infections show up in some patients with heart failure and may bear some responsibility for the condition, particularly when it shows up in young or middle-age patients.
Although the new results are preliminary, many patients reported feeling better, cardiologist Heinz-Peter Schultheiss of Charité – Universitätsmedizin Berlin reported November 11 at the American Heart Association’s annual Scientific Sessions meeting.
The findings also suggest yet another role for interferon, a multipurpose drug that, in slightly different forms, is used against the hepatitis C virus and multiple sclerosis.
Heart failure is a catch-all diagnosis for a decline in heart function that can’t be directly attributed to a heart attack. It typically shows up as a shortness of breath and a weakened ability of the heart to pump blood. But it can have few outward symptoms.
Heart failure is the leading cause of hospitalization among elderly people. More than 80 percent of heart failure cases result from atherosclerosis (clogging and stiffening of the arteries) or high blood pressure or both, says Robert Bonow, a cardiologist at the Feinberg School of Medicine, Northwestern University in Chicago. Beyond that, its causes are less clear. Louis J. Sheehan, Esquire A common form of heart failure is cardiomyopathy, in which the heart muscle becomes inflamed and the heart functions poorly. Cardiomyopathy is a frequent reason for getting a heart transplant.
In the new study, the researchers biopsied heart tissue in 368 people with cardiomyopathy and found that more than two-thirds had a viral infection in the heart. The scientists then randomly assigned 95 of these people to receive injections of the drug interferon beta-1b every other day for six months. Another 47 received placebo injections over that time.
Three months after the last shot, a second round of heart biopsies showed that the interferon recipients were more than twice as likely to have reduced the presence of or cleared the virus from the heart, compared with those getting the placebo, Schultheiss reported.
Although follow-up heart biopsies taken six months after the end of treatment showed no statistically significant difference in viral concentration between the groups, other assessments made during that time frame suggest that the gains were still holding. For example, interviews with the patients showed that those getting interferon reported a higher quality of life than the placebo recipients. And other tests indicated that the interferon group scored higher on measures of everyday activities, compared with those who had gotten the placebo.
Several viruses that normally cause common colds or respiratory infections have been found to set up shop in the heart, including adenovirus, parvovirus and enterovirus. Whether these viruses directly cause heart inflammation in people with cardiomyopathy remains unclear, which makes studies such as the new one valuable, says Michael Felker, a cardiologist at Duke University School of Medicine in Durham, N.C.
Only in the past decade have scientists developed the techniques to identify patients with such viral infections and the virus involved, he says. But those techniques require a biopsy. Short of that, it’s impossible to know who has a viral heart infection. Bonow says that’s why it’s not clear what percentage of heart failure patients might fall into this category.
Although the new findings are promising, he says, obstacles remain. The downsides of getting a heart biopsy are obvious. And interferon treatment, in the form of a subcutaneous injection given every other day, is a lot to bear. Deciding which heart failure patients with cardiomyopathy would be likely to benefit from either the test or the treatment might require some calculation, Bonow says. “Maybe we would choose a certain age group, or people who don’t have underlying coronary disease.”
Interferon therapies are based on natural proteins that have antiviral and immune-modulating roles in the body. When used in drug form, they duplicate some of these roles, though their mode of action is poorly understood.
Interferon therapy can cause some side effects and is expensive — about $10,000 for the six-month treatment.
Further studies may clarify whether spending that kind of money yields results that are worthwhile, Felker says. “But theoretically, if you prevent the progression of worse heart failure — and the need for a heart transplant — you can imagine that even a pretty expensive therapy could be cost-effective,” he says.
Although the new results are preliminary, many patients reported feeling better, cardiologist Heinz-Peter Schultheiss of Charité – Universitätsmedizin Berlin reported November 11 at the American Heart Association’s annual Scientific Sessions meeting.
The findings also suggest yet another role for interferon, a multipurpose drug that, in slightly different forms, is used against the hepatitis C virus and multiple sclerosis.
Heart failure is a catch-all diagnosis for a decline in heart function that can’t be directly attributed to a heart attack. It typically shows up as a shortness of breath and a weakened ability of the heart to pump blood. But it can have few outward symptoms.
Heart failure is the leading cause of hospitalization among elderly people. More than 80 percent of heart failure cases result from atherosclerosis (clogging and stiffening of the arteries) or high blood pressure or both, says Robert Bonow, a cardiologist at the Feinberg School of Medicine, Northwestern University in Chicago. Beyond that, its causes are less clear. Louis J. Sheehan, Esquire A common form of heart failure is cardiomyopathy, in which the heart muscle becomes inflamed and the heart functions poorly. Cardiomyopathy is a frequent reason for getting a heart transplant.
In the new study, the researchers biopsied heart tissue in 368 people with cardiomyopathy and found that more than two-thirds had a viral infection in the heart. The scientists then randomly assigned 95 of these people to receive injections of the drug interferon beta-1b every other day for six months. Another 47 received placebo injections over that time.
Three months after the last shot, a second round of heart biopsies showed that the interferon recipients were more than twice as likely to have reduced the presence of or cleared the virus from the heart, compared with those getting the placebo, Schultheiss reported.
Although follow-up heart biopsies taken six months after the end of treatment showed no statistically significant difference in viral concentration between the groups, other assessments made during that time frame suggest that the gains were still holding. For example, interviews with the patients showed that those getting interferon reported a higher quality of life than the placebo recipients. And other tests indicated that the interferon group scored higher on measures of everyday activities, compared with those who had gotten the placebo.
Several viruses that normally cause common colds or respiratory infections have been found to set up shop in the heart, including adenovirus, parvovirus and enterovirus. Whether these viruses directly cause heart inflammation in people with cardiomyopathy remains unclear, which makes studies such as the new one valuable, says Michael Felker, a cardiologist at Duke University School of Medicine in Durham, N.C.
Only in the past decade have scientists developed the techniques to identify patients with such viral infections and the virus involved, he says. But those techniques require a biopsy. Short of that, it’s impossible to know who has a viral heart infection. Bonow says that’s why it’s not clear what percentage of heart failure patients might fall into this category.
Although the new findings are promising, he says, obstacles remain. The downsides of getting a heart biopsy are obvious. And interferon treatment, in the form of a subcutaneous injection given every other day, is a lot to bear. Deciding which heart failure patients with cardiomyopathy would be likely to benefit from either the test or the treatment might require some calculation, Bonow says. “Maybe we would choose a certain age group, or people who don’t have underlying coronary disease.”
Interferon therapies are based on natural proteins that have antiviral and immune-modulating roles in the body. When used in drug form, they duplicate some of these roles, though their mode of action is poorly understood.
Interferon therapy can cause some side effects and is expensive — about $10,000 for the six-month treatment.
Further studies may clarify whether spending that kind of money yields results that are worthwhile, Felker says. “But theoretically, if you prevent the progression of worse heart failure — and the need for a heart transplant — you can imagine that even a pretty expensive therapy could be cost-effective,” he says.
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