October 21, 2011
In sub-Saharan Africa, tuberculosis is the disease that most often brings people with HIV into the clinic for treatment. Infection with both diseases is so common that in South Africa, for instance, 70% of tuberculosis patients are HIV positive. How best to treat these doubly infected patients– who number around 700,000 globally– is the subject of a new study, published in The New England Journal of Medicine, by scientists at Columbia University’s Mailman School of Public Health and CAPRISA (Centre for the AIDS Programme of Research in South Africa).
The authors had previously shown that integrating antiretroviral therapy (ART) concurrently with tuberculosis treatment reduces mortality among these patients and is preferable to treating the diseases sequentially. The new study investigates the best timing for introducing treatment for HIV. The researchers find that the optimal time for antiretroviral treatment depends on the patient’s immune status. Patients with very low T-cell counts, a measure of how well the immune system is working, appear to do better with an earlier integration of treatment for HIV.
Full study findings are available online in the October 20 issue of NEJM.
October 21, 2011
A commonly prescribed blood pressure-lowering medication appears to kick start recovery in the unaffected brain hemisphere after a stroke by boosting blood vessel growth, a new University of Georgia study has found.
The discovery, based on a study using rats and published recently in the online journal PLoS ONE, occurred only because the team, led by Susan Fagan, professor of clinical and administrative pharmacy at the UGA College of Pharmacy, struck a new path in stroke research by examining the healthy side of brain after the stroke occurred.
“I’m very excited because I think we can harness the restorative properties of the contralesional hemisphere-the other side of the brain-with drug therapies,” Fagan said. “When most researchers study stroke they compare the animal’s side of the brain that’s damaged to the opposite side, assuming that that side is normal or not affected.”
October 20, 2011
A recent UT Southwestern Medical Center study found that estrogen regulates energy expenditure, appetite and body weight, while insufficient estrogen receptors in specific parts of the brain may lead to obesity.
“Estrogen has a profound effect on metabolism,” said Dr. Deborah Clegg, associate professor of internal medicine and senior author of the study published Oct. 5 in Cell Metabolism. “We hadn’t previously thought of sex hormones as being critical regulators of food intake and body weight.”
The mouse study is the first to show that estrogen, acting through two hypothalamic neural centers in the brain, keeps female body weight in check by regulating hunger and energy expenditure. Female mice lacking estrogen receptor alpha – a molecule that sends estrogen signals to neurons – in those parts of the brain became obese and developed related diseases, such as diabetes and heart disease.
October 20, 2011
An investigational malaria vaccine — regarded as promising after earlier clinical trials — continued to show efficacy in African children in initial results from a large phase III trial, researchers reported.
Children who got the vaccine as intended had about a 44% reduction in the risk of a first clinical episode of the disease, compared with those who got a non-malaria comparator vaccine, according to Mary Hamel, MD, of the CDC, and colleagues.
The vaccine, dubbed RTS,S/AS01, also protected against severe disease, Hamel and colleagues reported online in the New England Journal of Medicine.
October 18, 2011
Chronic obstructive pulmonary disease (COPD) leads to persistent inflammation of the airways and is typically managed with corticosteroids, a class of anti-inflammatory medication. However, corticosteroids do not improve survival nor alter the progression of COPD and may reduce lung symptoms as little as 20 percent. A new study led by researchers at the Johns Hopkins Bloomberg School of Public Health, found why corticosteroids do not work well for COPD patients and how additional treatment with sulforaphane—an ingredient of broccoli and other vegetables—can improve the effectiveness of corticosteroids. The study was published online October 17, 2011, in advance of print in the Journal of Clinical Investigation.
COPD is a major public health problem for both the developed and the developing world, and is most often caused by cigarette smoking or exposure to pollutants from combustion. Characterized by chronic bronchitis and emphysema, COPD is the third leading cause of death in the U.S. and affects 24 million Americans and 210 million people worldwide.
Histone deacetylase 2 (HDAC2) is critical component in a chain of reactions that enable corticosteroids to reduce inflammation. However, HDAC2 is substantially reduced in the lung tissue of individuals with COPD. In the study, Johns Hopkins researchers found that S-nitrosylation causes HDAC2 dysfunction and leads to corticosteroid insensitivity in the alveolar macrophages of the lungs of individuals with COPD. S-nitrosylation of HDAC2 occurs from exposure to cigarette smoke, a primary cause of COPD.
October 18, 2011
New research has shown for the first time that omega-3 in fish oil could “substantially and significantly” reduce the signs and symptoms of osteoarthritis.
According to the University of Bristol study, funded by Arthritis Research UK and published in the journal Osteoarthritis and Cartilage, omega-3-rich diets fed to guinea pigs, which naturally develop osteoarthritis, reduced disease by 50 per cent compared to a standard diet.
The research is a major step forward in showing that omega-3 fatty acids, either sourced from fish oil or flax oil, may help to slow down the progression of osteoarthritis, or even prevent it occurring, confirming anecdotal reports and “old wives’ tales” about the benefits of fish oil for joint health.
Lead researcher Dr John Tarlton, from the Matrix Biology Research group at the University of Bristol’s School of Veterinary Sciences, said classic early signs of the condition, such as the degradation of collagen in cartilage and the loss of molecules that give it shock-absorbing properties, were both reduced with omega-3.
October 18, 2011
A protein in the nucleus of breast cancer cells that plays a role in fueling the growth of aggressive tumors may be a good target for new drugs, reports a research team at the Duke Cancer Institute.
The finding, published in the October 18, 2011, print issue of the journal Cancer Cell, presents a potential new way to inhibit breast cancer growth among so-called estrogen receptor negative cancers, which are especially lethal because they don’t respond to current hormone therapies.
“This is validation of a new drug target for a subset of breast cancers that have poor treatment options,” said the study’s senior author, Donald McDonnell, PhD, chairman of the Duke Department of Pharmacology and Cancer Biology.
October 17, 2011
Antiviral drugs used to target the herpes virus could be effective at slowing the progression of Alzheimer’s disease (AD), a new study shows.
The University of Manchester scientists have previously shown that the herpes simplex virus type 1 (HSV1) is a risk factor for Alzheimer’s when it is present in the brains of people who have a specific genetic risk to the disease.
AD is an incurable neurodegenerative condition affecting about 18 million people worldwide. The causes of the disease or of the abnormal protein structures seen in AD brains – amyloid plaques and neurofibrillary tangles – are completely unknown.
The Manchester team has established that the herpes virus causes accumulation of two key AD proteins – β-amyloid (Aβ) and abnormally phosphorylated tau (P-tau) – known to be the main components of plaques and tangles respectively. Both proteins are thought by many scientists to be involved in the development of the disease.
“We have found that the viral DNA in AD brains is very specifically located within amyloid plaques,” said Professor Ruth Itzhaki, who led the team in the University’s Faculty of Life Sciences. “This, together with the production of amyloid that the virus induces, suggests that HSV1 is a cause of toxic amyloid products and of plaques.
October 17, 2011
Within the next 20 years it is expected the number of people with Alzheimer’s disease (AD) will double from its current figure of half a million to one million.
A new study has looked at whether certain types of drugs used to treat high blood pressure, also called hypertension, might have beneficial effects in reducing the number of new cases of Alzheimer’s disease each year.
The team of researchers from the University of Bristol have looked at whether drugs already being used to treat hypertension, particularly ones that specifically reduce the activity of a biochemical pathway, called the renin angiotensin system, might reduce the occurrence of Alzheimer’s and another common type of dementia called vascular dementia.
The study, conducted with the support from North Bristol NHS Trust and published online in the Journal of Alzheimer’s Disease, stems from work by one of the team’s members, Dr Patrick Kehoe. Dr Kehoe, who is a Reader in Translational Dementia Research and co-leads the Dementia Research Group at Frenchay Hospital, Bristol, is a leading authority on the possible role of the renin angiotensin system in Alzheimer’s.
October 13, 2011
Itching is one of the most prevalent side effects of powerful, pain-killing drugs like morphine, oxycodone and other opioids. The opiate-associated itch is so common that even women who get epidurals for labor pain often complain of itching. For many years, scientists have scratched their own heads about why drugs that so effectively suppress pain also induce itch.
Now in mice, researchers at Washington University School of Medicine in St. Louis have shown they can control opioid-induced itching without interfering with a drug’s ability to relieve pain. The discovery raises tantalizing possibilities for new treatments to eliminate itch in cancer and surgery patients as well as others who rely on opioids to relieve chronic and severe pain.
The investigators report the findings Oct. 14 in the journal Cell.