Researchers at the Johns Hopkins Bloomberg School of Public Health have, for the first time, shown that infection with dengue virus turns on mosquito genes that makes them hungrier and better feeders, and therefore possibly more likely to spread the disease to humans. Specifically, they found that dengue virus infection of the mosquito's salivary gland triggered a response that involved genes of the insect's immune system, feeding behavior and the mosquito's ability to sense odors. The researchers findings are published in PLoS Pathogens. Dengue virus is primarily spread to people by the mosquito Aedes aegypti. Over 2.5 billion people live in areas where dengue fever is endemic. The World Health Organization estimates that there are between 50 million and 100 million dengue infections each year.
Scientists looking for ways to get minute doses of drugs, so-called "nano-medicines", into the right places in the human body have turned to "backpacking" bacteria to ferry the cargo. This week, at the 243rd National Meeting & Exposition of the American Chemical Society (ACS) in San Diego, Dr David H Gracias, from Johns Hopkins University in Baltimore, Maryland, gave an account of the progress he and his team are making in this area. Gracias told the press: "Cargo-carrying bacteria may be an answer to a major roadblock in using nano-medicine to prevent, diagnose and treat disease." Nano-technology concerns itself with making ultra-tiny devices, small enough to fit a million or so on the head of a pin. In medicine the idea is to use them to transport particles of medication, sensors and other materials to precise locations in the human body.
Bringing the goal of personalized medicine a step closer, scientists who design anti-cancer treatments and clinical trials now have access to a huge cancer knowledge resource, thanks to a collaboration between industry and academia. A report in the 28 March online issue of Nature describes how the Cancer Cell Line Encyclopedia (CCLE) brings together genome data and predictors of drug response for 947 cancer cell lines. The ultimate cancer treatment is one that matches the right drug to the right target in the right patient. This is the goal of personalized medicine. But to realize this goal, treatment designers need to know the specific genome alterations in the individual, how sensitive they are to specific drugs, and then tailor the drugs accordingly. For each cancer cell line, the CCLE compiles information on gene expression, chromosomal copy number, and massively parallel sequencing data.
Shortly after a mouse embryo starts to form, some of its stem cells undergo a dramatic metabolic shift to enter the next stage of development, Seattle researchers report. These stem cells start using and producing energy like cancer cells. This discovery is published in EMBO, the European Molecular Biology Organization journal. "These findings not only have implications for stem cell research and the study of how embryos grow and take shape, but also for cancer therapy, " said the senior author of the study, Dr. Hannele Ruohola-Baker, University of Washington professor of biochemistry. The study was collaborative among several research labs in Seattle. The metabolic transition they discovered occurs very early as the mouse embryo, barely more than a speck of dividing cells, implants in the mother's uterus.
Researchers say a 3.4 million-year-old fossilized foot found in Ethiopia did not belong to a member of Australopithecus afarensis, the hominin species of our early upright-walking ancestor "Lucy", but to a tree-climbing hominin cousin with whom she and her relatives co-existed. They write about how they came to this conclusion in the 29 March online issue of Nature. The fossil of the partial foot was found in 3.4-million-year-old rocks at Woranso-Mille in the Afar region of Ethiopia, where lead author Dr Yohannes Haile-Selassie, curator of physical anthropology at The Cleveland Museum of Natural History in the US, led the field research. Bones of Australopithecus afarensis, have also been found in the area, which is known locally as Burtele. Haile-Selassie and colleagues say the partial foot fossil, which was discovered in February 2009, indicates that more than one species of early human ancestor with different means of locomotion, one walking upright, and the other climbing trees, existed between 3 and 4 million years ago: "The Burtele partial foot clearly shows that at 3.