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| Latest in medical technology |
 Scientists Engineer First Caffeine-addicted Bacteria |
First caffeine-addicted bacteria developed in lab may help combat water pollution, say scientists. They described bacteria being "addicted" to caffeine in a way that promises practical uses ranging from decontamination of wastewater to bioproduction of medications for asthma. Jeffrey E. Barrick and colleagues noted that caffeine and related chemical compounds have become important water pollutants due to widespread use in coffee, soda pop, tea, energy drinks, chocolate and certain medications. These include prescription drugs for asthma and other lung diseases. The scientists knew that a natural soil bacterium, Pseudomonas putida CBB5, can actually live solely on caffeine and could be used to clean up such environmental contamination. So they set out to transfer genetic gear for metabolizing, or breaking down, caffeine from P. putida into that old workhorse of biotechnology, E. coli, which is easy to handle and grow. They reported their success in doing so, as well as use of the E. coli for decaffeination and measuring the caffeine content of beverages. It describes development of a synthetic packet of genes for breaking down caffeine and related compounds that can be moved easily to other microbes. When engineered into certain E. coli, the result was bacteria literally addicted to caffeine. The genetic packet could have applications beyond environmental remediation, the scientists said, citing potential use as a sensor to measure caffeine levels in beverages, in recovery of nutrient-rich byproducts of coffee processing and for the cost-effective bioproduction of medicines. Their findings were reported in the journal ACS Synthetic Biology. SOURCE: Medindia.net |
| Brain Scans Help Predict Criminal Behavior |
First caffeine-addicted bacteria developed in lab may help combat water pollution, say scientists. They described bacteria being "addicted" to caffeine in a way that promises pThe paper, which is to be published in the Proceedings of the National Academy of Sciences, studied impulsive and antisocial behavior and centered on the anterior cingulate cortex (ACC), a portion of the brain that deals with regulating behavior and impulsivity. The study demonstrated that inmates with relatively low anterior cingulate activity were twice as likely to reoffend than inmates with high-brain activity in this region. "These findings have incredibly significant ramifications for the future of how our society deals with criminal justice and offenders," said Dr. Kent A. Kiehl, who was senior author on the study and is director of mobile imaging at MRN and an associate professor of psychology at the University of New Mexico. "Not only does this study give us a tool to predict which criminals may reoffend and which ones will not reoffend, it also provides a path forward for steering offenders into more effective targeted therapies to reduce the risk of future criminal activity." The study looked at 96 adult male criminal offenders aged 20-52 who volunteered to participate in research studies. This study population was followed over a period of up to four years after inmates were released from prison. "These results point the way toward a promising method of neuroprediction with great practical potential in the legal system," said Dr. Walter Sinnott-Armstrong, Stillman Professor of Practical Ethics in the Philosophy Department and the Kenan Institute for Ethics at Duke University, who collaborated on the study. "Much more work needs to be done, but this line of research could help to make our criminal justice system more effective." The study used the Mind Research Network's Mobile Magnetic Resonance Imaging (MRI) System to collect neuroimaging data as the inmate volunteers completed a series of mental tests. "People who reoffended were much more likely to have lower activity in the anterior cingulate cortices than those who had higher functioning ACCs," Kiehl said. "This means we can see on an MRI a part of the brain that might not be working correctly -- giving us a look into who is more likely to demonstrate impulsive and anti-social behavior that leads to re-arrest." The anterior cingulate cortex of the brain is "associated with error processing, conflict monitoring, response selection, and avoidance learning," according to the paper. People who have this area of the brain damaged have been "shown to produce changes in disinhibition, apathy, and aggressiveness. Indeed, ACC-damaged patients have been classed in the 'acquired psychopathic personality' genre." Kiehl says he is working on developing treatments that increase activity within the ACC to attempt to treat the high-risk offenders. |
| South Africa to Follow India, China to Make Life-Saving Medications Affordable |
Doctors Without Borders explains that the South African government should follow the lead of its BRICS peers to make life-saving medications affordable. Speaking in Johannesburg, MSF South Africa media liaison officer Kate Ribet said other BRICS countries have fulfilled the commitments they made in July 2011 to enact public health safeguards spelled out in World Trade Organization (WTO) agreements. "Decisive moves by Brazil, India and China have saved hundreds of millions of taxpayer dollars and dramatically increased access to medicine by bringing down prices," Xinhua quoted Ribet as saying. "South Africa lags far behind because it still grants and protects patent monopolies of pharmaceutical companies, at the expense of South Africans' health," she added. MSF said South Africa's patent system currently allows for patent protection of pharmaceuticals additional to WTO 20-year requirements, and does not take advantage of flexibilities for protecting health, like overriding patents with a compulsory license (CL) when drugs are priced out of reach for those in need. In India, a CL on cancer drug sorafenib was upheld earlier this month, making generic sorafenib available in India for $1 per 200 mg tablet, 97 percent less than the brand name product. "In South Africa, where no generic versions of this medicine are available, patients must pay 203.50 rands (about $2.2) for the same tablet," Ribet said. MSF said when Brazil issued a CL on the widely-used antiretroviral efavirenz in 2007, the switch to a generic saved the Brazilian government an estimated $103.5 million in treating HIV/AIDS from 2007-2011. According to the group, Pretoria has never issued a CL, despite being a major purchaser of antiretroviral drugs and TB treatment. This is partly due to outdated laws. By protecting poor-quality patent monopolies of pharmaceutical companies, South Africa cannot obtain more affordable generic medications available from BRICS countries like India, nor develop substantial local pharmaceutical production capacity. MSF and the Treatment Action Campaign (TAC) are jointly campaigning for the amendment of South Africa's patent laws, to put the country on par with its BRICS peers in protecting public health. |
| Plant Based Foods Contain DNA Damaging Toxins |
Harmful effects of flavorings on the DNA of cells are now being studied in a paired group of food chemistry and cancer biology. They found that liquid smoke flavoring, black and green teas and coffee activated the highest levels of a well-known, cancer-linked gene called p53. The p53 gene becomes activated when DNA is damaged. Its gene product makes repair proteins that mend DNA. The higher the level of DNA damage, the more p53 becomes activated. "We don't know much about the foods we eat and how they affect cells in our bodies," says Scott Kern, M.D., the Kovler Professor of Oncology and Pathology at the Johns Hopkins University School of Medicine. "But it's clear that plants contain many compounds that are meant to deter humans and animals from eating them, like cellulose in stems and bitter-tasting tannins in leaves and beans we use to make teas and coffees, and their impact needs to be assessed."Kern cautioned that his studies do not suggest people should stop using tea, coffee or flavorings, but do suggest the need for further research. The Johns Hopkins study began a year ago when graduate student Samuel Gilbert, working in Kern's laboratory, noted that a test Kern had developed to detect p53 activity had never been used to identify DNA-damaging substances in food. For the study, published online February 8 in Food and Chemical Toxicology, Kern and his team sought advice from scientists at the U.S. Department of Agriculture about food products and flavorings. "To do this study well, we had to think like food chemists to extract chemicals from food and dilute food products to levels that occur in a normal diet," he says. Using Kern's test for p53 activity, which makes a fluorescent compound that "glows" when p53 is activated, the scientists mixed dilutions of the food products and flavorings with human cells and grew them in laboratory dishes for 18 hours. Measuring and comparing p53 activity with baseline levels, the scientists found that liquid smoke flavoring, black and green teas and coffee showed up to nearly 30-fold increases in p53 activity, which was on par with their tests of p53 activity caused by a chemotherapy drug called etoposide. Previous studies have shown that liquid smoke flavoring damages DNA in animal models, so Kern's team analyzed p53 activity triggered by the chemicals found in liquid smoke. Postdoctoral fellow Zulfiquer Hossain tracked down the chemicals responsible for the p53 activity. The strongest p53 activity was found in two chemicals: pyrogallol and gallic acid. Pyrogallol, commonly found in smoked foods, is also found in cigarette smoke, hair dye, tea, coffee, bread crust, roasted malt and cocoa powder, according to Kern. Gallic acid, a variant of pyrogallol, is found in teas and coffees. Kern says that more studies are needed to examine the type of DNA damage caused by pyrogallol and gallic acid, but there could be ways to remove the two chemicals from foods and flavorings. "We found that Scotch whiskey, which has a smoky flavor and could be a substitute for liquid smoke, had minimal effect on p53 activity in our tests," says Kern. Liquid smoke, produced from the distilled condensation of natural smoke, is often used to add smoky flavor to sausages, other meats and vegan meat substitutes. It gained popularity when sausage manufacturers switched from natural casings to smoke-blocking artificial casings. Other flavorings like fish and oyster sauces, tabasco and soy sauces, and black bean sauces showed minimal p53 effects in Kern's tests, as did soybean paste, kim chee, wasabi powder, hickory smoke powders and smoked paprika. |
| Surgical Menopause may Up Risk of Stroke, Alzheimer's Disease |
Women who lose estrogen from surgical menopause had a decline in cognitive function and dementia, say researchers. "This is what the clinical studies indicate and our animal studies looking at the underlying mechanisms back this up," said Brann, corresponding author of the study in the journal Brain. "We wanted to find out why that is occurring. We suspect it's due to the premature loss of estrogen." In an effort to mimic what occurs in women, Brann and his colleagues looked at rats 10 weeks after removal of their estrogen-producing ovaries that were either immediately started on low-dose estrogen therapy, started therapy 10 weeks later or never given estrogen. When the researchers caused a stroke-like event in the brain's hippocampus, a center of learning and memory, they found the rodents treated late or not at all experienced more brain damage, specifically to a region of the hippocampus called CA3 that is normally stroke-resistant. To make matters worse, untreated or late-treated rats also began an abnormal, robust production of Alzheimer's disease-related proteins in the CA3 region, even becoming hypersensitive to one of the most toxic of the beta amyloid proteins that are a hallmark of Alzheimer's. Both problems appear associated with the increased production of free radicals in the brain. In fact, when the researchers blocked the excessive production, heightened stroke sensitivity and brain cell death in the CA3 region were reduced. Interestingly the brain's increased sensitivity to stressors such as inadequate oxygen was gender specific, Brann said. Removing testes in male rats, didn't affect stroke size or damage. Although exactly how it works is unknown, estrogen appears to help protect younger females from problems such as stroke and heart attack. Their risks of the maladies increase after menopause to about the same as males. Follow up studies are needed to see if estrogen therapy also reduces sensitivity to the beta amyloid protein in the CA3 region, as they expect, Brann noted. Brann earlier showed that prolonged estrogen deprivation in aging rats dramatically reduces the number of brain receptors for the hormone as well as its ability to prevent strokes. Damage was forestalled if estrogen replacement was started shortly after hormone levels drop, according to the 2011 study in the journal Proceedings of the National Academy of Sciences. The surprising results of the much-publicized Women's Health Initiative - a 12-year study of 161,808 women ages 50-79 - found hormone therapy generally increased rather than decreased stroke risk as well as other health problems. Critics said one problem with the study was that many of the women, like Brann's aged rats, had gone years without hormone replacement, bolstering the case that timing is everything |