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Long denigrated as vestigial or useless, the appendix now appears to have a reason to be —as a “safe house” for the beneficial bacteria living in the human gut. Drawing upon a series of observations and experiments, Duke University Medical Center investigators postulate that the beneficial bacteria in the appendix that aid digestion can ride out a bout of diarrhea that completely evacuates the intestines and emerge afterwards to repopulate the gut. Their theory appears online in the Journal of Theoretical Biology. The appendix is a slender two- to four-inch pouch located near the juncture of the large and small intestines. While its exact function in humans has been debated by physicians, it is known that there is immune system tissue in the appendix. The researchers believe that the immune system cells found in the appendix are there to protect, rather than harm, the good bacteria.

 

Researchers report in the New England Journal of Medicine that they can potentially target chemotherapy for breast cancer to only those women most likely to benefit, sparing the majority of patients from unnecessary side effects. The multi-center study, led by University of Michigan Comprehensive Cancer Center researchers, found women whose breast cancer expressed a protein called HER-2 were most likely to benefit from adding the drug Taxol to the chemotherapy regimen, while women whose tumors were fueled by estrogen but did not express HER-2 did not get any benefit from the added Taxol. About 15 percent to 20 percent of breast cancers express HER-2.

 

Science has found one likely contributor to the way that some folks eat to live and others live to eat. Researchers at the State University of New York at Buffalo have found that people with genetically lower dopamine, a neurotransmitter that helps make behaviors and substances more rewarding, find food to be more reinforcing than people without that genotype. In short, they are more motivated to eat, and they eat more. The findings appear in the journal Behavioral Neuroscience. Insights into genes and eating could inspire custom-tailored treatment programs for obesity, perhaps including genetically targeted drugs.

 

A new study finds treatment for breast cancer differs between African-American women and white women, though the differences are partly dependent on insurance type. The study, published in the journal CANCER, found that among patients with breast cancer that had spread to the lymph nodes, African-Americans were less likely to have adjuvant cancer therapy than white women. Researchers from the University of Michigan and Wayne State University also found that white women were almost five times more likely to take Tamoxifen, a widely-used cancer therapy medication, and over three times more likely to have chemotherapy. Women with early-stage breast cancer who had government health insurance were less likely to have combination breast-conserving cancer surgery and radiation, and more likely to have mastectomy without radiation than patients enrolled in non-governmental plans.

 

Relatives of patients with Parkinson’s disease may have an increased risk of developing dementia or cognitive impairment, according to a report in the Archives of Neurology. Parkinson’s disease is characterized by a decline in the functions of the central nervous system, such as motor skills and speech. Several studies have shown an increased risk of dementia in first-degree relatives of Parkinson’s disease patients, while other studies have not confirmed the association. The co-occurrence of Alzheimer’s disease and Parkinson’s disease in families and in individuals may be due to the sharing of susceptibility genetic variants, researchers at the Mayo Clinic College of Medicine, Rochester, Minnesota, said. Relatives of patients who experienced the onset of Parkinson’s disease at age 66 or younger had a particularly increased risk of developing dementia or cognitive impairment, the researchers found. The observed associations suggest the action of shared familial susceptibility factors, genetic or nongenetic, they said.

 

PNEUMONIA: PATIENTS WHO RECEIVED VACCINE HAVE LOWER DEATH RATE
Among patients hospitalized with community-acquired pneumonia, those who had previously received the pneumococcal vaccine had a lower risk of death and admission to the intensive care unit than patients who were not vaccinated, according to a report in the Archives of Internal Medicine. Community-acquired pneumonia is a common condition resulting in considerable illness and death. A vaccine against Streptococcus pneumoniae known as PPV has been has been available since 1983. Most guidelines recommend PPV for those at high risk of developing pneumonia, including older adults and nursing home residents. Researchers at the University of Alberta, Edmonton, Canada found that patients vaccinated with PPV were less likely to die or be admitted to the ICU than those who had not been vaccinated (10 percent vs. 21 percent). The researchers also found an economic benefit to use of the vaccine thanks to the reduction in the need for costly ICU admissions.

 

A study from Switzerland suggests that men who have surgery for prostate cancer appear less likely to die of the disease within 10 years than men who choose other treatment options, especially if they are younger or have cancers with certain tumor cell characteristics, according to a report in the Archives of Internal Medicine. Prostate cancer treatments are still being debated because they have not yet been compared in a randomized trial, in which men would be randomly assigned to one treatment or another. Treatment choice is strongly influenced by patient and physician personal preferences and experiences, researchers from Geneva University, Switzerland said. The researchers found that at 10 years, patients treated with radiotherapy or watchful waiting had a significantly increased risk of death from prostate cancer compared with patients who underwent prostatectomy. Ten-year survival rates from prostate cancer were 83 percent for prostatectomy, 75 percent for radiotherapy, 72 percent for watchful waiting, 41 percent for hormone therapy, and 71 percent for other treatment.

 

Researchers in a multi-center international study have identified a new gene that, if mutated, may increase a woman’s risk of breast cancer by more than a third. Further, the researchers from University of Michigan School of Public Health in collaboration with researchers in Spain, Israel, and multiple centers in the United States, found that the gene, HMMR, interacts with the well-known breast cancer gene BRCA1. Alternations in either gene cause genetic instability and interfere with cell division, which could be a path to breast cancer developing. The study, published online in Nature Genetics, leads researchers to not just a single gene, but a pathway that may be a potential target for treating or detecting breast cancer. In particular, the risk of breast cancer in women under age 40 who carry the HMMR variation was 2.7 times the risk in women without this variation. In addition, those women were diagnosed an average of 12 months younger than women from the control group, suggesting that HMMR is linked to early-onset breast cancer.

 

Scientists may have discovered a new way of killing tumors in what they hope could one day lead to alternative forms of cancer treatments. Researchers at the University of Manchester identified a key gene that appears to play a critical role in the normal process of cell division. A protein in cells called “Bub 1” is essential for normal cell division to take place. If the gene that generates Bub 1 is switched off, then the cells are unable to divide successfully. The researchers hope that because deactivating Bub 1 had such a profound effect on cell division at all stages of a cell’s life—known as the “cell cycle”—it will have a similar effect on cancer cells. Unlike some other genes that become mutated in cancer cells, the Bub 1 gene appears normal, indicating that it behaves in exactly the same way in cancer cells as it does in healthy cells. The researchers said if this is the case, they are confident that switching it off will stop cancer cells proliferating too.

 

A combination of drugs widely used to treat infections caused by HIV appears to stop brain damage caused by the virus as well, according to a study published in the journal Neurology. The study, conducted by researchers at the Clinic of Infectious Diseases SÄS in Borås, Sweden, involved 53 men and women. The participants were given a combination of several antiretroviral drugs known as Highly Active Anti-Retroviral Therapy (HAART) for one year. Researchers tested the participants’ cerebrospinal fluid before and after treatment to see if there were elevated levels of a particular biomarker for brain injury called neurofilament light protein. The study found 21 people had high levels of the protein, suggestive of brain damage, at the beginning of treatment. But after three months of taking HAART, those high levels of protein fell to normal levels in nearly half of the patients. After one year of treatment, only four people still had high levels of this particular biomarker for brain damage. 

 

Selective serotonin reuptake inhibitors (SSRIs), a group of drugs commonly used to treat depression, may double the risk of gastrointestinal bleeding, according to researchers from Wake Forest University School of Medicine and colleagues. When the drugs are taken with aspirin and other similar pain medications, the risk is more than six times higher. The research, reported online in Alimentary Pharmacology & Therapeutics, suggests clinicians who prescribe these medications should be aware of the potential risk and may need to consider alternatives. In addition, the researchers said regulatory authorities should consider revising existing package inserts to highlight the magnitude of the risk.

 

African-American men are more likely than white men to have their prostate cancer return after treatment, but their disease is no more aggressive when it does recur, according to by researchers at the Duke Prostate Center. African-American men tend to have higher levels of PSA, or prostate-specific antigen, a biomarker that indicates the presence of prostate cancer at initial diagnosis, despite being diagnosed at younger ages. The study, published online in the journal Cancer, found that African-American men were 28 percent more likely to experience a disease recurrence, but found that the aggressiveness of the disease was similar in the two racial groups. The researchers said their findings suggests that there may be an underlying genetic and biologic component that predisposes African-American men to prostate disease.

 

A new report from the National Research Council recommends that government agencies enhance their efforts to incorporate genomic data into risk assessments of chemicals and medicines, and calls for a concerted effort to fully develop these methods' potential to protect public health. Chemicals and drugs often cause health problems by altering gene expression and other cell activity, and research on these so-called “toxicogenomic” processes could eventually lead to more sensitive toxicity tests that can supplement current tests, the report says. Toxicogenomic tests can also pinpoint individuals with genetic vulnerabilities and help them avoid chemicals or medications that might make them ill. A major, coordinated effort approaching the scale of the Human Genome Project is needed both to develop these technologies fully and to address the ethical challenges they pose, such as protecting the confidentiality of individuals' genetic information, the report says. 

 

GlaxoSmithKline said it entered into a global collaboration with Synta Pharamceuticals to jointly develop and commercialize STA-4783, a first-in-class, small-molecule, oxidative stress inducer that is entering late-stage clinical development for the treatment of metastatic melanoma. Under the terms of the agreement, GSK will pay Synta, based in Lexington, Massachussetts, $80 million in upfront payments and milestones that could bring the total value of the deal to more than $1 billion. The companies will share responsibility for development and commercialization of STA-4783 in the U.S., and GSK will have exclusive responsibility for development and commercialization of STA-4783 outside the U.S. STA-4783 is a novel, injectable, investigational drug candidate that kills cancer cells by elevating oxidative stress levels beyond a breaking point, triggering programmed cell death. In preclinical models STA-4783 showed potent killing of a broad range of cancer cell types at high doses, and an ability to strongly enhance the efficacy of certain chemotherapy agents, with minimal additional toxicity, at moderate doses.

 

The majority of non-medical anabolic-androgenic steroid (AAS) users are not cheating athletes or risk-taking teenagers, according to a survey published in the online in the Journal of the International Society of Sports Nutrition. Researchers found the typical male user is about 30 years old, well-educated, and earning an above-average income in a white-collar occupation. Whereas athletes are tempted to take anabolic steroids to improve sports performance, the study suggests that physical self-improvement motivates the unrecognized majority of non-medical AAS users who particularly want to increase muscle mass, strength, and physical attractiveness. Although often considered similar to abusers of narcotics and other illicit drugs, non-medical AAS users are different. These users follow carefully planned drug regimens in conjunction with a healthy diet, ancillary drugs, and exercise. As opposed to the spontaneous and haphazard approach seen in abusers of psychotropic drugs, these users strategically plan everything to maximize benefits and minimize harm.

 

A report in the World Health Organization Bulletin calls for urgent attention to the politically sensitive issue of border control, and the need for coherent and robust national plans in the face of a catastrophic flu pandemic. The report comes after the recent confirmation of person-to-person transmission of a strain of avian influenza in northern Sumatra in Indonesia. Although the outbreak was contained by voluntary quarantine and rapid administration of antiviral medication, scientists admitted that the world had “dodged a bullet” and “may not be so lucky next time.” Researchers at the London School of Hygiene and Tropical Medicine in the United Kingdom, who authored the study, found while most European countries are better prepared than a year ago, fewer than half provided defined plans for distribution of antivirals or guidance on where vaccines would be stored and how they would be distributed and administered. The study also found two-thirds of national plans depart from WHO guidelines on the crucial step of limiting people’s movement from affected to unaffected areas.

 

An immune system protein could act as an early warning system for lung cancer, according to research published online in the journal Thorax. Lung cancer kills about 900,000 people every year, and can take 20 years or more to develop fully. But it is usually only diagnosed at an advanced stage, when the chances of successful treatment are slim. Researchers tested blood samples from patients with and without lung cancer for a panel of seven autoantibodies—immune system proteins directed at the body’s own tissues in response to specific chemical signals in the body. These particular autoantibodies are associated with “solid tumors,” such as lung, breast, ovarian, and prostate cancers, and triggered when cancerous changes are taking place. The researchers found the presence of all seven autoantibodies, and very high levels of at least one of the seven, in almost eight out of 10 samples taken from patients with confirmed lung cancer. These autoantibodies were found in eight out of the nine patients whose cancer had not infiltrated the lymph nodes, the body’s gatekeepers. This indicates that the disease had not yet spread elsewhere and offers an 80 percent chance of a cure.

 

Scientists at the University of Utah have developed new peptides that appear to be significantly more effective at blocking HIV's entry into cells than other drugs in their class. In a paper published online in the Proceedings of the National Academy of Sciences, the researchers say these peptides are sufficiently potent to begin pre-clinical studies as a new class of agents for the prevention and treatment of HIV/AIDS. The researchers were particularly interested in developing drugs to bind to an essential "pocket" structure found in all HIV strains that was previously identified as a promising drug target using structures determined at U.S. Department of Energy's Brookhaven National Laboratory. Numerous previous attempts to target this pocket failed to produce potent and non-toxic pocket-specific entry inhibitors. In the current work, the researchers used a high-throughput technique to screen a library containing hundreds of millions of peptides to identify the rare peptides that would bind to the pocket structure and inhibit HIV entry. The effort led to the discovery of D-peptides that the researchers said had up to a 40,000-fold improved antiviral potency over previously reported D-peptides. The structures also suggest ways to engineer the peptides to reduce the chance of drug resistance.

 

Tooth loss may predict the development of dementia late in life, according to research published in The Journal of the American Dental Association. Numerous past studies have shown that patients with dementia are more likely than patients without the condition to have poor oral health. Few researchers, however, have examined the relationship from the opposite direction, to determine whether poor oral health actually may contribute to the development of dementia. Researchers from the University of Kentucky College of Medicine and College of Dentistry in Lexington, studied data from 144 participants in the Nun Study, a study of aging and Alzheimer’s disease among Catholic sisters of the School Sisters of Notre Dame. The researchers used dental records and results of annual cognitive examinations to study participants from the Order’s Milwaukee province who were 75 to 98 years old. Of the participants who did not have dementia at the first examination, those with zero to nine teeth had an increased risk of developing dementia during the study compared with those who had 10 or more teeth, the researchers found. They proposed several possible reasons for the association between tooth loss and dementia: not only periodontal disease but also early-life nutritional deficiencies, infections, or chronic diseases that may result simultaneously in tooth loss and damage to the brain. The researchers, however, note further studies would be necessary to see if there was a causal relationship between tooth loss and dementia.

A report from the nation’s leading cancer organizations shows cancer death rates decreased on average 2.1 percent per year from 2002 through 2004, nearly twice the annual decrease of 1.1 percent per year from 1993 through 2002. The findings appear in the journal Cancer. Among the general population, the report shows that long-term declines in cancer death rates continued through 2004 for both sexes, and despite overall higher death rates for men, the declines from 2002 through 2004 were 2.6 percent per year among men and 1.8 percent per year among women. Death rates decreased for the majority of the top 15 cancers in men and women. Important declines were noted for the three leading causes of cancer deaths in men: lung, prostate, and colorectal cancers. In women, deaths rates from colorectal cancer and breast cancer decreased, while the rate of increase for lung cancer deaths slowed substantially. The researchers credit effective tobacco control, screening, early detection, and appropriate treatment for the drop in cancer deaths.

 

Researchers at MIT have discovered a link between a gene believed to promote long lifespan and a pathway that flushes cholesterol from the body. The finding could help researchers create drugs that lower the risk of diseases associated with high cholesterol, including atherosclerosis and Alzheimer's disease. The study focused on a gene called SIRT1, which the researchers found prevents cholesterol buildup by activating a cellular pathway that expels cholesterol from the body via HDL (high density lipoprotein, or “good cholesterol”). In the journal Molecular Cell, researchers report that low SIRT1 levels in mice lead to cholesterol buildup in cells such as macrophages, a type of immune cell, due to reduced activity of a protein called LXR (liver X receptor). LXR is responsible for transporting cholesterol out of macrophage cells. When full of cholesterol, the macrophages can generate plaques that clog arteries. SIRT1 boosts LXR activity, so that cholesterol is expelled from macrophages and out of the body by HDL.

The researchers said drugs that enhance the effects of SIRT1 could lower the risk of cholesterol-related diseases.

 

HIV: MANY IN AFRICA DON’T CONTINUE TREATMENT
More than one-third of patients receiving HIV medication in Africa discontinue their treatment within two years, according to a study published in PLoS Medicine. Boston University researchers found that 77.5 percent of patients remained on treatment after an average period of 9.9 months. Of the patients no longer on treatment, just under half had died and half had lost contact with the clinics for undetermined reasons. The average retention rate at two years was estimated at 61.6 percent, but individual programs ranged widely, between 46 percent and 85 percent. The researchers said one way to improve retention might be to start treating people with HIV earlier, before they become seriously ill.

 

Using household cleaning sprays and air fresheners as little as once a week can raise the risk of developing asthma in adults, according to researchers at the Municipal Institute of Medical Research in Barcelona. Such products have been associated with increased asthma rates in cleaning professionals, but a similar effect in nonprofessional users has never before been shown. The epidemiological study, the first to investigate the effects of cleaning products on occasional users rather than occupational users, appeared in the American Journal of Respiratory and Critical Care Medicine. The researchers found the risk of developing asthma increased with frequency of cleaning and number of different sprays used, but on average was about 30 to 50 percent higher in people regularly exposed to cleaning sprays than in others. The researchers found that cleaning sprays, especially air fresheners, furniture cleaners, and glass-cleaners, had a particularly strong effect.

 

Persons who reported chronic job strain after a first heart attack had about twice the risk of experiencing another coronary heart disease event such as heart attack or unstable angina than those without chronic job strain, according to a study in JAMA. Several studies have shown that job strain increases the risk of a first coronary heart disease event, but researchers at the Université Laval, Québec City, and colleagues conducted a study to determine whether job strain increases the risk of a recurrent event after a first heart attack. These results suggest that preventive interventions aimed at reducing job strain might have a significant impact on recurrent coronary heart disease events, the researchers said.

 

Workers who have diabetes with neuropathic symptoms such as numbness or tingling in feet or hands lose the equivalent of 1.4 hours a week or $3.65 billion per year in health-related lost productive time, a study in the Journal of Occupational and Environmental Medicine finds. The 1.4 hours lost was more than twice the amount of lost time of diabetic workers without neuropathic symptoms. Investigators at the Geisinger Center for Health Research in Danville, Pennsylvania, who conducted the study, found when they compared health-related lost productive time, it was 18 percent higher in diabetics with symptoms and 5 percent higher in diabetics without symptoms. Those with diabetes were about twice more likely than those without diabetes to be unemployed. The pharmaceutical company Pfizer supported this research.

 

A new study concludes that routine testing for HIV, as recommended by the Centers for Disease Control, may violate many states’ laws, according to researchers at Georgia State University College of Law. The study, published in the open-access journal PLoS ONE, found that more than thirty states require specific consent before HIV testing may occur. Nearly half of them require that consent to be in writing. Those state laws stand in contrast to recommendations issued by the CDC in 2006 for routine HIV testing for all Americans between ages 13 and 64. According to the CDC, adults should be tested after being notified, unless they refuse. Organizations around the country are now considering how to implement the CDC’s recommendations.