A shocking diet: Researchers describe microbe that ‘eats’ electricity

There have been plenty of fad diets that captured the public’s imagination over the years, but Harvard scientists have identified what may be the strangest of them all — sunlight and electricity.Led by Peter Girguis, the John L. Loeb Associate Professor of the Natural Sciences, and Arpita Bose, a post-doctoral fellow in Organismic and Evolutionary Biology, a team of researchers showed that the commonly found bacterium Rhodopseudomonas palustris can use natural conductivity to pull electrons from minerals located deep in soil and sediment while remaining at the surface, where they absorb the sunlight needed to produce energy. The study is described in a February 26 paper in Nature Communications.”When you think about electricity and living organisms, most people default to Mary Shelley’s Frankenstein, but we’ve long understood that all organisms actually use electrons — what constitutes electricity — to do work,” Girguis said. “At the heart of this paper is a process called extracellular electron transfer (EET), which involves moving electrons in and out of cells. What we were able to show is that these microbes take up electricity, which goes into their central metabolism, and we were able to describe some of the systems that are involved in that process.”In the wild, the microbes rely on iron to provide the electrons they need to fuel energy generation, but tests in the lab suggest the iron itself isn’t critical for this process. By attaching an electrode to colonies of the microbes in the lab, researchers observed that they could take up electrons from a non-ferrous source, suggesting they might also use other electron-rich minerals — such as other metals and sulfur compounds — in the wild.”That’s a game-changer,” Girguis said. “We have understood for a long time that the aerobic and anaerobic worlds interact mainly through the diffusion of chemicals into and out of those domains. Accordingly, we also believe this process of diffusion governs the rates of many biogeochemical cycles. But this research indicates…that this ability to do EET is, in a sense, an end-run around diffusion. That could change the way we think about the interactions between the aerobic and anaerobic worlds, and might change the way we calculate the rates of biogeochemical cycling.”Using genetic tools, researchers were also able to identify a gene that is critical to the ability to take up electrons. …

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BPA linked to breast cancer tumor growth

UT Arlington biochemists say their newly published study brings researchers a step closer to understanding how the commonly used synthetic compound bisphenol-A, or BPA, may promote breast cancer growth.Subhrangsu Mandal, associate professor of chemistry/biochemistry, and Arunoday Bhan, a PhD student in Mandal’s lab, looked at a molecule called RNA HOTAIR. HOTAIR is an abbreviation for long, non-coding RNA, a part of DNA in humans and other vertebrates. HOTAIR does not produce a protein on its own but, when it is being expressed or functioning, it can suppress genes that would normally slow tumor growth or cause cancer cell death.High levels of HOTAIR expression have been linked to breast tumors, pancreatic and colorectal cancers, sarcoma and others.UT Arlington researchers found that when breast cancer and mammary gland cells were exposed to BPA in lab tests, the BPA worked together with naturally present molecules, including estrogen, to create abnormal amounts of HOTAIR expression. Their results were published online in February by the Journal of Steroid Biochemistry and Molecular Biology.”We can’t immediately say BPA causes cancer growth, but it could well contribute because it is disrupting the genes that defend against that growth,” said Mandal, who is corresponding author on the paper.”Understanding the developmental impact of these synthetic hormones is an important way to protect ourselves and could be important for treatment,” he said.Bhan is lead author on the new paper. Co-authors include Mandal lab members Imran Hussain and Khairul I Ansari, as well as Linda I. Perrotti, a UT Arlington psychology assistant professor, and Samara A.M. Bobzean, a member of Perrotti’s lab.”We were surprised to find that BPA not only increased HOTAIR in tumor cells but also in normal breast tissue,” said Bhan. He said further research is needed, but the results beg the question — are BPA and HOTAIR involved in tumor genesis in addition to tumor growth?BPA has been widely used in plastics, such as food storage containers, the lining of canned goods and, until recently, baby bottles. It belongs to a class of endocrine disrupting chemicals, or EDCs, which have been shown to mimic natural hormones. These endocrine disruptors interfere with hormone regulation and proper function of human cells, glands and tissue. …

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Mesothelioma Chemotherapy – 5 Commonly Asked Mesothelioma Chemotherapy Questions

Mesothelioma patients usually have some questions that they want answers for when they want to commence on Chemotherapy. These include:1. What is chemotherapy for mesothelioma? Chemotherapy involves one or more anti-cancer drugs taken either orally in pill form, or intravenously, or, in the case of pleural mesothelioma, injected directly into the lungs. These drugs inhibit the growth of cancerous cells, but they also damage normal healthy cells as well leading to the development of side effects.2. What are the common side effects of mesothelioma chemotherapy? Side effects are very common with the use of many Chemotherapy agents. The commonly seen side effects include:* hair loss * nausea * vomiting * diarrhea * constipation * anemia * hemorrhagingChemotherapy also causes many complicated side effects within the …

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Drug dosing for older heart patients should differ

Aug. 16, 2013 — Older heart patients present unique challenges for determining the optimal dosages of medications, so a new study from researchers at Duke Medicine offers some rare clarity about the use of drugs that are used to treat patients with heart attacks.For certain heart patients older than age 75, a half-dose of the anti-platelet drug prasugrel works about as well as the typical dosage of clopidogrel, according to a team led by the Duke Clinical Research Institute that looked at a sub-study of a large clinical trial.”As people live longer throughout the world, it’s increasingly important to establish appropriate treatments for conditions such as acute coronary syndromes that commonly occur later in life,” said Matthew T. Roe, M.D., MHS, associate professor of medicine at Duke and lead author of a study published Aug. 20, 2013, in the journal Circulation.”These patients are very vulnerable to side effects, including bleeding, if therapies are not properly dosed,” Roe said. “Additionally, existing practice guidelines have few specific recommendations for older patients with acute coronary syndromes as little evidence has been accrued from prior clinical trials in this population.”People older than age 75 comprise less than 10 percent of the U.S. population, but account for 35 percent of patients with acute coronary syndrome (ACS), which includes a recent heart attack or unstable chest pain. ACS is typically treated with anti-platelet therapies.Earlier studies, for example, had shown that the platelet inhibitor prasugrel reduced the risk of adverse outcomes compared with clopidogrel in ACS patients undergoing coronary stent implantation. Those studies used a 60-mg initial dose followed by a 10-mg/day maintenance dose.At that dosage level, however, patients older than age 75 had an increased risk of intracranial and fatal bleeding, as did younger patients weighing 132 pounds or less. The results led to warnings by the U.S. Food and Drug Administration and the European Medicines Agency for the use of the 10 mg/day maintenance dose of prasugrel in those populations, and consideration of a reduced dose (5 mg/day) to mitigate bleeding complications.To examine whether older patients might benefit from a lower dosage of prasugrel, the Duke-led researchers analyzed more than 2,000 older patients who participated in a large trial called TRILOGY ACS that compared prasugrel with clopidogrel to manage acute coronary syndromes without coronary stent implantation or coronary bypass surgery.The findings from this study, the first long-term data on outcomes specifically from elderly patients treated with the reduced dose of prasugrel, determined that a smaller dosage of 5-mg/day of prasugrel presented no greater risk of bleeding problems than the commonly prescribed 75-mg dose of clopidogrel in the elderly population.”The findings from our study indicate how difficult it is to identify the right dose of anti-clotting medications for the elderly, to improve outcomes after a heart attack,” said co-author Magnus Ohman, professor of medicine at Duke and chairman of the TRILOGY ACS study. …

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Ingested nanoparticle toxicity

June 26, 2013 — Ingestion of commonly encountered nanoparticles at typical environmental levels is unlikely to cause overt toxicity, according to US researchers. Nevertheless there is insufficient evidence to determine whether chronic exposures could lead to subtle alterations in intestinal immune function, protein profiles, or microbial balance.Writing in a forthcoming issue of the International Journal of Biomedical Nanoscience and Nanotechnology, researchers have compared existing laboratory and experimental animal studies pertaining to the toxicity of nanoparticles most likely to be intentionally or accidentally ingested. Based on their review, the researchers determined ingestion of nanoparticles at likely exposure levels is unlikely to cause health problems, at least with respect to acute toxicity. Furthermore, in vitro laboratory testing, which often shows toxicity at a cellular level, does not correspond well with in vivo testing, which tends to show less adverse effects.Ingrid Bergin in the Unit for Laboratory Animal Medicine, at the University of Michigan in Ann Arbor and Frank Witzmann in the Department of Cellular and Integrative Physiology, at Indiana University School of Medicine, in Indianapolis, explain that the use of particles that are in the nano size range (from 1 billionth to 100 billionths of a meter in diameter, 1-100 nm, other thereabouts) are finding applications in consumer products and medicine. These include particles such as nano-silver, which is increasingly used in consumer products and dietary supplements for its purported antimicrobial properties. Nanoparticles can have some intriguing and useful properties because they do not necessarily behave in the same chemical and physical ways as non-nanoparticle versions of the same material.Nanoparticles are now used as natural flavor enhancers in the form of liposomes and related materials, food pigments and in some so-called “health supplements.” They are also used in antibacterial toothbrushes coated with silver nanoparticles, for instance in food and drink containers and in hygienic infant feeding equipment. They are also used to carry pharmaceuticals to specific disease sites in the body to reduce side effects. Nanoparticles actually encompass a very wide range of materials from pure metals and alloys, to metal oxide nanoparticles, and carbon-based and plastic nanoparticles. Because of their increasing utilization in consumer products, there has been concern over whether these small scale materials could have unique toxicity effects when compared to more traditional versions of the same materials.Difficulties in assessing the health risks of nanoparticles include the fact that particles of differing materials and shapes can have different properties. Furthermore, the route of exposure (e.g. …

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