January 26, 2006, 12:52 AM CT
'Vioxx like' drugs may still be best option for arthritis
In a Nature Reviews of Drug Discovery article this month the scientists from Imperial College London and Queen Mary, University of London examine the use of selective inhibitors of cyclo-oxygenase-2 (COX-2).
They argue that eventhough this class of drugs, which includes Vioxx, has been associated with an increase in the risk of cardiovascular events such as heart attacks and strokes in some patients, the same may be true for traditional non-steroid anti-inflammatory drugs (NSAIDs).
All NSAIDs, including COX-2 inhibitors, work by blocking the actions of both COX-1 and COX-2 enzymes. Blocking COX-2 relieves inflammation and pain, but blocking COX-1 can increase the risk of gastric ulcers and bleeds. For this reason COX-2 selective drugs were developed with the simple aim that they would retain the therapeutic actions of NSAIDs (linked to inhibition of COX-2) but lose the gastric side effects (linked to inhibition of COX-1).
The scientists reviewed over one hundred papers on the subject and looked at the latest recommendations from organisations such as the American Federal Drugs Administration on the use of COX-2 inhibitors and NSAIDs.
The scientists point out that the calls for the removal of COX-2 inhibitors, and a return to using NSAIDs, may cause additional problems. Eventhough NSAIDs have been marketed for many years, they have never been mandatory to meet the clinical trial standards now set for COX-2 inhibitors, meaning they may not be any safer.........
Posted by: Mark Permalink
January 26, 2006, 12:10 AM CT
Anxious fathers make caesarean ops more painful
In a study involving 65 women scheduled for an elective caesarean, scientists found that the way their birth partners felt during the operation influenced the womans own levels of fear and anxiety about the operation.
This increased the amount of pain the woman felt immediately after the operation, which could affect her immediate recovery as well as potentially influence other related factors such as breast feeding and parent-child bonding.
The lead scientists from the University of Bath (Dr Keogh) and Imperial College London (Dr Anita Holdcroft ) suggest that helping prepare the birth partner for a caesarean, both at antenatal classes and before the operation, could help reduce the pain experienced by the mother and improve the birth experience.
One in four babies born in the UK is now delivered by caesarean section (CS), with a number of hospitals delivering almost 30 per cent in this way. Fear of pain during childbirth is often cited as one of the contributory factors for the increasing rate of CS delivery.
But despite the popular notion that caesarean deliveries are the 'easy option', with respect to overall pain experiences compared with labour pain, this may not be the case.
"Caesarean sections involve major surgery and are often performed whilst the mother is awake under regional anaesthesia which numbs the lower part of the body, said Dr Ed Keogh from the University of Bath.........
Posted by: Emily Permalink
January 26, 2006, 11:52 AM CT
Link Between Cat Faeces And Schizophrenia
Research published recently in Procedings of the Royal Society B, shows how the invasion or replication of the parasite Toxoplasma gondii in rats may be inhibited by using anti-psychotic or mood stabilising drugs.
The scientists tested anti-psychotic and mood stabilising medications used for the therapy of schizophrenia on rats infected with T. gondii and found they were as, or more, effective at preventing behaviourial alterations as anti-T. gondii drugs. This led them to think that T. gondii may have a role in the development of some cases of schizophrenia.
Dr Joanne Webster from Imperial College London, and lead researcher said: "Eventhough we are certainly not saying that exposure to this parasite does definitely lead to the development of schizophrenia, this and prior studies do show there may be a link in a few individuals, providing new clues for how we treat toxoplasmosis and schizophrenia".
Prior epidemiological and neuropathological studies have indicated some cases of schizophrenia may be associated with environmental factors, such as exposure to the parasite T. gondii. At the same time several of the medications used to treat schizophrenia have been shown to posess anti-parasitic and in particular anti-T.gondii properties. This led the authors to suspect that the anti-psychotic activity of these medications may be due to their inhibition of these parasites.........
Posted by: Daniel Permalink
January 25, 2006, 9:01 PM CT
Defective Synapse Generator Leads To Alzheimer
A new UCLA/Veterans Affairs study implicates defects in the machinery that creates connections between brain cells as responsible for the onset of Alzheimer disease.
The defect in PAK enzyme signaling pathways - vital to creation of these connections, or synapses - is correlation to loss of a synapse protein in certain forms of mental retardation, such as Down syndrome. The new finding suggests therapies designed to address the PAK defect could treat cognitive problems in both patient populations.
The peer-reviewed journal Nature Neuroscience published the study online Jan. 15.
"The emerging lesson is that cognitive problems in Alzheimer disease are correlation to defects in the machinery controlling neuronal connections, not the lesions observed by pathologists," said principal investigator Greg Cole, professor of medicine and neurology at the David Geffen School of Medicine and Alzheimer Disease Research Center at UCLA, and the Geriatric Research Education and Clinical Center at the Veterans Affairs Greater Los Angeles Health Care System and Sepulveda Ambulatory Care Center. "Our findings show that PAK defects in the brains of Alzheimer patients appear sufficient to directly cause cognitive difficulties".
In some families, early-onset Alzheimer disease can be caused by mutations in different genes that all increase the production of a sticky protein called Abeta42 (Ab42). The increase causes the protein to form aggregates, little clusters or long filaments that pile up and make lesions in the brain called plaques.........
Posted by: Daniel Permalink
January 25, 2006, 8:51 PM CT
Nano Motor Powered By Solar Energy
Image courtesy of UCLA
Chemists at Italy's University of Bologna, UCLA and the California NanoSystems Institute have designed and constructed a molecular motor of nanometer size that does not consume fuels; their nano motor is powered only by sunlight. The research, federally funded by the National Science Foundation, will be published Jan. 31 in Proceedings of the National Academy of Sciences (PNAS).
The nano motor can work continuously without any external interference, and operates without consuming or generating chemical fuels or waste, said Fraser Stoddart, UCLA's Fred Kavli Professor of NanoSystems Sciences and director of the institute.
"We design and make sunlight-powered nano motors and then 'test drive' them much as an engineer would a new motorcar," Stoddart said. "It is as if we had managed to get a solar-powered motor car onto the road and running".
Precisely how light-powered nano motors will be used in the future is still not clear, Stoddart said, but he listed many possible areas for applications: nanoelectronics, molecular computers and nano valves that perhaps could be used for the delivery of anti-cancer drugs and other medications.
"The achievement reported in PNAS is the culmination of a research effort lasting a quarter of a century and involving hundreds of students and millions of dollars," Stoddart said.........
Posted by: Scott Permalink
January 25, 2006, 8:42 PM CT
Heart And Alzheimer's Disease Protein Imaged
Karl H. Weisgraber, Ph.D.
Scientists for the first time have created a three-dimensional image of apolipoprotein E, a protein long associated with cardiovascular disease and more recently with Alzheimer's disease, as it appears when it is bound to fat-like substances known as lipids.
Using the technique known as x-ray crystallography, researchers at the Gladstone Institute of Cardiovascular Disease (GICD) have created the highest-resolution x-ray structure of a lipoprotein particle to date.
The work focuses apoE4, one of three specific forms of apolipoprotein E, usually known as apoE. The breakthrough has already answered long-standing questions about the configuration of apoE4 in its active, or native, state. A complete understanding of the protein's functioning will be a key factor for development of future therapeutic interventions, as per the researchers.
Details of the works are published in the January 13 edition of the Journal of Biological Chemistry.
"This is the first successful use of x-ray crystallography to reveal the structure of a protein bound to lipids," explains senior author Karl Weisgraber, PhD, a senior investigator at both GICD and the Gladstone Institute of Neurological Disease (GIND). "It's crucial to understand this molecule, since it plays such a pivotal role in both cardiovascular and neurological disease.........
Posted by: Daniel Permalink
January 24, 2006, 9:42 PM CT
Obesity Is A Risk Factor For Kidney Failure
Scientists at the University of California, San Francisco have determined that there is a strong relationship between being obese and developing end-stage renal disease, or kidney failure.
The long-range study found that the obese have up to a seven times greater risk of kidney failure than normal weight people, suggesting that obesity should be considered a risk factor for the condition, and that kidney failure is yet another consequence of obesity.
"There are more and more people with kidney failure, but it hasn't been appreciated much that kidney failure can be a consequence of obesity," said Chi-yuan Hsu, MD, UCSF assistant professor of medicine and lead author of the study. "We think this study is important because it demonstrates quite convincingly that people who are obese or overweight are at much higher risk of kidney failure."
The study, reported in the January 3 issue of the Annals of Internal Medicine, was conducted jointly with Kaiser Permanente of Northern California Division of Research.
Research findings showed that being even moderately overweight nearly doubles the risk of developing the condition, which is a complete failure of the kidneys to process waste so that dialysis or transplantation become necessary.
"If you are mildly overweight, not even frankly obese, you are roughly 90 percent more likely to develop end-stage renal failure," Hsu said, with the risk reaching over 700 percent greater for the morbidly obese.........
Posted by: JoAnn Permalink
January 24, 2006, 9:38 PM CT
Resistance Patterns To Aids Drugs
Some HIV medications lead to the development of drug-resistant HIV when patients take as few as two percent of their medications. For other medications, resistance occurs only when patients take most of their pills. These differences appear to be explained by the different levels of viral "fitness" of the drug-resistant HIV, say AIDS scientists in a new study.
The research, led by David Bangsberg, MD, MPH, an AIDS specialist at the University of California, San Francisco, is published in the January 9 issue of the journal AIDS.
Viral "fitness" refers to the inherent ability of a virus to replicate and cause disease. Incomplete pill-taking by patients causes HIV to mutate and become resistant to the effects of the medications, while the medications that were consumed, in turn, cause the newly resistant virus to become less fit.
The type of medicine also factors in. Differences in viral fitness of mutated resistant virus occur between different classes of antiretroviral drugs, said Bangsberg, who is an associate professor of medicine at UCSF and director of the UCSF Epidemiology and Prevention Interventions Center at San Francisco General Hospital Medical Center.
When patients succeed in completely suppressing HIV, which requires that patients take all or almost all of their medications as directed, resistant strains either do not occur or are suppressed, he added.........
Posted by: Mark Permalink
January 23, 2006, 9:41 PM CT
Obesity And Sleep Apnea In Kids
Jennifer Miller, M.D
Growth hormone helps hundreds of children with a rare disorder that causes them to gorge on food, but for some, starting therapy can worsen a dangerous nighttime breathing problem, University of Florida scientists have found.
Sleep apnea disrupts breathing during sleep and is common among morbidly obese children, including those with Prader-Willi syndrome, a disease that compels them to eat nonstop. Scientists say that uncovering how to treat obesity and related problems in children genetically wired to be overweight could help them better battle childhood obesity in general.
Growth hormone has shown to be one of the most effective ways to treat children and adults with Prader-Willi. But UF scientists found that starting therapys can worsen or trigger sleep apnea in obese children exposed to colds, potentially leading to death, as per findings published online recently in The Journal of Clinical Endocrinology and Metabolism.
"Every kid we studied had abnormal sleep at the beginning, before growth hormone," said Dr. Jennifer Miller, a UF assistant professor of pediatrics and the study's lead author. "On growth hormone, most of them got better but not all of them. The ones that got worse tended to be school age. Some of them were just entering school and then they were coming home with upper-respiratory infections.........
Posted by: JoAnn Permalink
January 23, 2006, 9:30 PM CT
A Robot That Follows Patients As They Move
The MRI and Computerized axial tomography scan may one day have a robotic cousin capable of following and peering into patients as they move around.
A University of Florida engineer has designed a robot to shadow and shoot X-ray video of sufferers of orthopedic injuries as they walk, climb stairs, stand up from a seated position or pursue other normal activities - and maybe even athletic ones like swinging a bat.
UF mechanical and aerospace engineer Scott Banks' goal is to augment static images of patients' bones, muscles and joints with an interior view of these and other parts in action during normal physical activity. By merging such full-motion X-rays with computerized representations, orthopedic surgeons will make better diagnoses, suggest more appropriate therapys and get a clearer idea of post-operative successes and failures, he said.
"Our goal is come up with a way to observe and measure how joints are moving when people are actually using them," Banks said. "We think this will be tremendously powerful, not only for research but also in the clinical setting as well".
Complaints about orthopedic injuries are among the most common reasons people visit the doctor, as per the American Academy of Orthopedic Surgeons. More than 8 million people were hospitalized in 2003 for musculoskeletal conditions or injuries, which are estimated to cost the United States at least $215 billion annually.........
Posted by: Mark Permalink