The parasite that escaped out of Africa: Tracing origins of malaria parasite

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An international team of scientists has traced the origin of Plasmodium vivax, the second-worst malaria parasite of humans, to Africa, according to a study published this week in Nature Communications. Until recently, the closest genetic relatives of human P. vivax were found only in Asian macaques, leading researchers to believe that P. vivax originated in Asia.The study, led by researchers from the Perelman School of Medicine at the University of Pennsylvania, found that wild-living apes in central Africa are widely infected with parasites that, genetically, are nearly identical to human P. vivax.This finding overturns the dogma that P. vivax originated in Asia, despite being most prevalent in humans there now, and also solves other vexing questions about P. vivax infection: how a mutation conferring resistance to P. vivax occurs at high frequency in the very region where this parasite seems absent and how travelers returning from regions where almost all humans lack the receptor for P. vivax can be infected with this parasite.Of Ape and Human ParasitesMembers of the labs of Beatrice Hahn, MD, and George Shaw, MD, PhD, both professors of Medicine and Microbiology at Penn, in collaboration with Paul Sharp, PhD, an evolutionary biologist from the University of Edinburgh, and Martine Peeters, PhD, a microbiologist from the Institut de Recherche pour le Dveloppement and the University of Montpellier, tested over 5,000 ape fecal samples from dozens of field stations and sanctuaries in Africa for P. vivax DNA. …


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#Africa, #African, #Alternative-Medicine, #America, #Duffy, #Edinburgh, #Microbiology, #Nature, #Pennsylvania, #Plasmodium, #Receptor, #School

Asian elephants reassure others in distress: First empirical evidence of consolation in elephants

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Asian elephants console others who are in distress, using physical touches and vocalizations, finds a study to be published in the open access journal PeerJ. The findings are the first empirical evidence of consolation in elephants, says lead author Joshua Plotnik, who began the research as a graduate student of psychology at Emory University.”For centuries, people have observed that elephants seem to be highly intelligent and empathic animals, but as scientists we need to actually test it,” he says.Consolation behavior is rare in the animal kingdom, with empirical evidence previously provided only for the great apes, canines and certain corvids.”With their strong social bonds, it’s not surprising that elephants show concern for others,” says co-author Frans de Waal, an Emory professor of psychology and director of Living Links at Emory’s Yerkes National Primate Research Center. “This study demonstrates that elephants get distressed when they see others in distress, reaching out to calm them down, not unlike the way chimpanzees or humans embrace someone who is upset.”Plotnik received his Ph.D. from Emory in 2010 and is currently a lecturer in conservation biology at Mahidol University in Thailand and CEO of Think Elephants International, a non-profit focused on education and conservation. His main research interest is convergent cognitive evolution: The independent evolution of similar features of intelligence in species of different lineages.While Plotnik was still at Emory, he and de Waal provided evidence that elephants can both recognize themselves in a mirror — a test of self-awareness passed only by some apes, dolphins and magpies — and problem-solve cooperatively.”Humans are unique in many ways, but not in as many ways as we once thought,” Plotnik says.The current study focused on a group of 26 captive Asian elephants spread over about 30 acres at an elephant camp in northern Thailand. For nearly a year, the researchers observed and recorded incidents when an elephant displayed a stress reaction, and the responses from other nearby elephants.The initial stress responses came from either unobservable, or obvious, stimuli: Events such as a dog walking past, a snake or other potentially dangerous animal rustling the grass, or the presence of another, unfriendly elephant. “When an elephant gets spooked, its ears go out, its tail stands erect or curls out, and it may emit a low-frequency rumble, trumpet and roar to signal its distress,” Plotnik says.The study found that nearby elephants affiliated significantly more with a distressed individual through directed, physical contact following a stress event than during control periods. As a typical example, a nearby elephant would go to the side of the distressed animal and use its trunk to gently touch its face, or put its trunk in the other animal’s mouth.The gesture of putting their trunks in each other’s mouths is almost like an elephant handshake or hug, Plotnik says. “It’s a very vulnerable position to put yourself in, because you could get bitten. It may be sending a signal of, ‘I’m here to help you, not hurt you.’”The responding elephants also showed a tendency to vocalize. …


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#African, #Agriculture, #Asian, #Emory, #Humans, #Pregnancy, #Psychology, #Study

Massachusetts" fire-safe cigarette law appears to decrease likelihood of residential fires

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A six-year-old Massachusetts law requiring that only “fire-safe” cigarettes (FSCs) be sold in the state appears to decrease the likelihood of unintentional residential fires caused by cigarettes by 28%, according to a new study by Harvard School of Public Health (HSPH) researchers.The study will appear online February 13, 2014 in the American Journal of Public Health.”This study is the first rigorous population-based study to evaluate the effectiveness of the fire-safe cigarette standards, and shows that science-based tobacco product regulation can protect the public health,” said lead author Hillel Alpert, research scientist at the Center for Global Tobacco Control at HSPH.Burning cigarettes left smoldering on a bed, furniture, or other flammable material are a leading cause of residential fires in the United States, generating hundreds of millions of dollars each year in property damage, health care costs, lost productivity, death, and injuries. Young children, seniors, African Americans, Native Americans, the poor, people living in rural areas or in substandard housing, and firefighters are especially at risk.To evaluate the effectiveness of Massachusetts’ Fire Safe Cigarette Law, the researchers analyzed seven years of data from 2004 to 2010 on accidental residential fires, including 1,629 caused by cigarettes. The information was reported to the Massachusetts Fire Incident Reporting System, a system maintained by the Massachusetts Department of Fire Services.The results appear to show that the likelihood of unintentional residential fires caused by cigarettes decreased by 28% after the Massachusetts law was enacted in 2008. The largest reductions were among cigarette fires in which human factors, such as falling asleep while smoking, were involved, and among fires that were ignited on materials, which are the scenarios for which the standard was developed.”This study confirms that the fire standard compliant (FSC) cigarette law has reduced the number of fires from cigarettes started by igniting furniture and bedding as it was designed to do,” said Massachusetts Fire Marshal Stephen Coan.”We now have the science to support that all tobacco companies throughout the world should voluntarily make their cigarettes less likely to ignite fires,” said Gregory Connolly, professor of the practice of public health and director of the HSPH Center for Global Tobacco Control.Story Source:The above story is based on materials provided by Harvard School of Public Health. Note: Materials may be edited for content and length.


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#African, #American, #Cancer, #Control, #Department, #Law, #Public, #School

South African healthcare workers face greater risk for TB, HIV

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A large-scale survey of South African healthcare workers has revealed major gaps in workplace protection against tuberculosis, HIV and hepatitis, according to a University of British Columbia health researcher.Presenting findings today at the 2014 annual meeting of the American Association for the Advancement of Science (AAAS), Dr. Annalee Yassi says issues such as confidentiality, stigma, technological capacity and staff training need to be addressed while improving hospital resources and protocols.Preliminary results of the 2012 baseline survey of more than 1,000 healthcare workers in three hospitals show that more than 68 per cent of patient care staff had never been screened for TB; nearly 20 per cent were not vaccinated against hepatitis; and 55 per cent did not wear respiratory protection when needed. Despite South Africa’s high TB and HIV rates — 18 per cent of its adult population is HIV-positive — and risk of hepatitis transmission, recapping of used needles before disposal and washing and reusing of gloves were common, with more than 20 per cent surveyed reporting needlestick injury or unprotected exposure to bodily fluids.Yassi, who is helping South Africa implement occupational health guidelines developed by the World Health Organization (WHO), says healthcare workers in developing countries face greater health challenges while serving significantly more patients.”In addition to massive workloads, healthcare workers in developing countries are more likely to get sick from the workplace,” says Yassi, a professor in UBC’s School of Population and Public Health, noting that healthcare workers in South Africa are at three times the risk of contracting TB than other South Africans, and more than seven times more likely to be hospitalized for drug-resistant TB. A 2013 WHO estimate showed South Africans were almost 300 times more likely to contract TB than Americans.”Considerable progress is being made, including better standard operating procedures and screening,” says Yassi. “But there’s much more we can do to ensure a healthy workplace for the international health care workforce.”Story Source:The above story is based on materials provided by University of British Columbia. Note: Materials may be edited for content and length.


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#African, #Africans, #Alzheimer, #British, #Ecology, #Hiv, #Major, #Organization, #Science, #Southafricans

Mixed genes: Interactive world map of human genetic history reveals likely genetic impacts of historical events

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When individuals from different groups interbreed, their offspring’s DNA becomes a mixture of the DNA from each admixing group. Pieces of this DNA are then passed along through subsequent generations, carrying on all the way to the present day. Researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, Oxford University and University College London (UCL) have now produced a global map detailing the genetic histories of 95 different populations across the world, spanning the last four millennia.The interactive world map that is accessible via the internet, details the histories of genetic mixing between each of the 95 populations across Europe, Africa, Asia and South America. It shows likely genetic impacts of historical events including European colonialism, the Mongol Empire, the Arab slave trade and European traders near the Silk Road mixing with people in China.The study, published this week in Science, is the first to simultaneously identify, date and characterise genetic mixing between populations. To do this, the researchers developed sophisticated statistical methods to analyse the DNA of 1490 individuals in 95 populations around the world. “DNA really has the power to tell stories and uncover details of humanity’s past,” said Simon Myers of Oxford University’s Department of Statistics and Wellcome Trust Centre for Human Genetics, co-senior author of the study. “Because our approach uses only genetic data, it provides information independent from other sources. Many of our genetic observations match historical events, and we also see evidence of previously unrecorded genetic mixing. For example, the DNA of the Tu people in modern China suggests that in around 1200CE, Europeans similar to modern Greeks mixed with an otherwise Chinese-like population. Plausibly, the source of this European-like DNA might be merchants travelling the nearby Silk Road.”The powerful technique, christened ‘Globetrotter’, provides insight into past events such as the genetic legacy of the Mongol Empire. …


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#African, #Agriculture, #Alzheimer, #China, #Dna, #Europe, #Genetic, #Genetics, #Germany, #London, #Result, #Study

Coffee growing: More biodiversity, better harvest

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Bees, birds and bats make a huge contribution to the high yields produced by coffee farmers around Mount Kilimanjaro – an example of how biodiversity can pay off. This effect has been described as result of a study now published in the „Proceedings of the Royal Society B“. It has been conducted by tropical ecologists of the University Wrzburg Biocenter, jointly with colleagues from the LOEWE Biodiversity and Climate Research Centre (BiK-F, Frankfurt/Main) and the Institute for experimental Ecology of the University of Ulm.A large amount of coffee is grown on Kilimanjaro, the East African massif almost 6000 meters high. The most traditional form of cultivation can be found in the gardens of the Chagga people. Hhere the sun-shy coffee trees and many other crop plants thrive in the shade of banana trees and other tall trees. However, the largest part of the coffee is grown on plantations. Usually, the plantations still feature a large number of shade trees. But these are progressively being chopped down because of the increasing replacement of “conventional coffee varieties, which rely on shade, by varieties that tolerate lots of sun and are more resistant to fungi,” explains Professor Ingolf Steffan-Dewenter, a tropical ecologist at the University of Wrzburg’s Biocenter. This crop intensification is expected to result in higher yields. The plantation harvests might however stagnate: If there are only few shade trees left, the habitat may become unsuitable for the animal species that pollinate the coffee, eat pests, and thereby help to improve the yield.Teamwork on the slopes of Mount KilimanjaroSteffan-Dewenter and his doctoral student Alice Classen therefore wanted to understand how bees, birds, bats and other animals contribute to pollination and to biological pest control in the coffee fields. …


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#African, #Agriculture, #Animals, #Biocenter, #Birds, #Chagga, #Coffee, #Ecology, #Institute, #University