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Archive - Aug 18, 2017

Mysteries in Development of Smallpox Vaccine—A Historical Investigation

Smallpox is an infectious disease caused by variola virus that has killed millions of people over the centuries. The disease is characterized by the growth of innumerable bumps that cover the entire body of the patient. The disease is fatal in 30% of cases, but this rate is much higher for hemorrhagic smallpox and flat-type smallpox. Vaccination against smallpox throughout the 19th and 20th centuries was successful and contributed to the eradication of the disease in 1977, after a successful worldwide campaign (1967-1977) coordinated by the World Health Organization. The vaccine was developed by British physician Edward Jenner in 1796 and the virus circulating in the vaccine was named as vaccinia virus. Cowpox virus, a cousin of variola virus, causes a mild smallpox-like disease in cows. The story goes that Jenner was told that milkers who acquired the "cow-version" of smallpox were immune to the human version of the disease. Thus, one day Jenner decided to perform a risky experiment. The researcher took pustular material from the lesion of a milker and used it to inoculate a young boy, the eight-year-old son of his gardener. If the hypothesis that previous cowpox infection protected humans from smallpox proved right, then the boy would not develop smallpox when later challenged with smallpox pustular material. Sure enough, the young boy remained immune to smallpox and the experiment was a milestone in the history of the smallpox vaccine (see additional information at Wikipedia link below). Following this success, vaccination (from the Latin vacca meaning cow) was adopted worldwide as the main strategy to prevent smallpox.

Ocean Channel in Bahamas Marks Genetic Divide in Brazilian Free-Tailed Bats

Brazilian free-tailed bats are expert flyers, capable of migrating hundreds of miles and regularly traveling more than 30 miles a night. But they pull up short at a narrow ocean channel that cuts across the Bahamas, dividing bat populations that last shared an ancestor hundreds of thousands of years ago. A new study, published online on August 17, 2017, in Ecology and Evolution, uncovers a dramatic and unexpected genetic rift between populations of Tadarida brasiliensis on either side of the Northwest and Northeast Providence Channels, about 35 miles across at their most narrow point. Genetic analysis of the populations suggests that bats from Florida colonized the northern Bahamian islands while bats from other parts of the Caribbean likely colonized the southern Bahamas. The open-access article is titled “Population Structure of a Widespread Bat (Tadarida Brasiliensis) in an Island System.” Why the bats balk at crossing a channel so narrow they can likely see land on the other side while in flight remains a mystery, said Kelly Speer, the study's lead author who completed the research while a master's student at the Florida Museum of Natural History. "Based on their mainland population behavior, we know they're able to disperse much farther than the distances between islands in the Caribbean," said Speer, now a doctoral student at the American Museum of Natural History. "It doesn't seem like distance is the factor, and there's no association with wind direction. We don't have any idea why they don't cross this channel." Because they can fly, bats are good models for studying mammal movement in fragmented habitats, Speer said.

How Cilia Beat in One Direction to Promote Fluid flow in the Brain

Researchers at Nagoya University in Japan have identified a molecule that enables cell appendages called cilia to beat in a coordinated way to drive the flow of fluid around the brain; this prevents the accumulation of this fluid, which otherwise leads to swelling of the head as found in the condition hydrocephalus. Some cells in the body contain long thin structures called cilia on their surfaces, which exhibit a whip-like motion that promotes the flow of fluid past the cell. Although these cilia are known to play vital roles in the body, much remains to be understood about their molecular components and the mechanisms by which they work. This is especially true for the cilia on cells that line the ventricles of the brain, which contain cerebrospinal fluid (CSF) that has various functions including cushioning the brain against potentially damaging impacts. A team at Nagoya University has shed light on this issue by revealing that a molecule called Daple is essential for cilia to adopt an arrangement by which they can beat in one direction at the same time, thereby creating a flow of fluid past the cell exterior. This arrangement on cell surfaces all along the lining of ventricles in the brain ensures the correct flow of CSF, which in turn prevents its accumulation associated with brain swelling known as hydrocephalus. The work was published in the July 25, 2017 issue of Cell Reports. The title of the open-access article is “Daple Coordinates Planar Polarized Microtubule Dynamics in Ependymal Cells and Contributes to Hydrocephalus.” The team revealed the importance of Daple by creating mutant mice that did not express the Daple protein. By approximately 20 days after birth, these mice had enlarged heads, similar to those seen in human hydrocephalus cases.

Solving ME/CFS Initiative (SMCI) Announces New Research Program at Brigham & Women’s Hospital to Study Myalgic Encephalomyelitis/Chronic Fatigue Syndrome(ME/CFS)

On August 16, 2017, the Solve ME/CFS Initiative (SMCI) announced that the SMCI and its partners are initiating a new ME/CFS Research Fund at Brigham and Women’s Hospital (BWH) in Boston, Massachusetts. The establishment of this fund supports the continuation of BWH’s Dr. David Systrom’s ME/CFS research. This work will further understanding of the autonomic, peripheral neuropathy, and cardiovascular features of ME/CFS. In other words, this research focuses on the involuntary nervous system, nerve pain in the hands and feet, and the heart and blood vessels. Specifically, the work aims to characterize the connection between small fiber polyneuropathy (nerve damage) and exertional intolerance during the course of cardiopulmonary (relating to the heart and the lungs) testing. Future study directions will include a continued focus on exertion intolerance with particular attention to the development of therapeutic interventions. Under Dr. Zaher Nahle, Chief Scientific Officer at SMCI’s leadership, the SMCI is committed to creating and advancing stand-alone ME/CFS programs, like this one, at major research universities and medical centers. The SMCI is extremely pleased to facilitate this work at the prestigious BWH. Notably, this was made possible by a donation from a visionary patient through the recently established “patient scientist” program, designed to facilitate patient participation in research through partnerships between patients, SMCI, and selected medical programs.