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Archive - Nov 19, 2018

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Activation of Inhibitory Neurons Prior to Epileptic Seizures Observed for First Time in Humans

(BY RACHEL DERITA, PhD Candidate,Thomas Jefferson University, Department of Cancer Biology) Epileptic seizures are established to neuroscience as global excitation of neurons in the brain. However, new research from Jefferson (Philadelphia University & Jefferson University) in Philadelphia and collaborating institutions has uncovered a previously unknown period of time before an epileptic seizure in which there is an activation of inhibitory neurons. “This is the first time, to our knowledge, that this phenomenon of inhibition at the start of a seizure has been observed in humans,” states senior author of the study Shennan Weiss, MD, PhD, Assistant Professor of Neurology and Head of the Thomas Jefferson Computational Epilepsy Laboratory at the Vickie & Jack Farber Institute for Neuroscience at Jefferson. Before now, this was a phenomenon only observed in chemically-induced seizures in research animals, and was therefore considered an artifact of the experimental models. In the current study, published online on September 4, 2018, in the Annals of Neurology, surgeons collaborating between Jefferson and the University of California at Los Angeles (UCLA), used electrodes to determine the exact location of the seizures occurring in an epilepsy patient. They then were able to track action potentials from single neurons, classified as either excitatory or inhibitory. It was observed that there was a burst of activity from the inhibitory neurons prior to activity of the excitatory neurons. Epileptic patients often experience a period of time prior to a seizure characterized by auras, confusion, and an inability to speak clearly or form coherent sentences.

New Work Suggests That Non-Homologous End-Joining (NHEJ) & Retrotransposons Led to Evolution of Spliceosome and Advance of Eukaryotic Life

A previously unappreciated interaction in the genome turns out to have possibly been one of the driving forces in the emergence of advanced life, billions of years ago. This discovery began with a curiosity for retrotransposons, known as "jumping genes," which are DNA sequences that copy and paste themselves within the genome, multiplying rapidly. Nearly half of the human genome is made up of retrotransposons, but bacteria hardly have them at all. Nigel Goldenfeld, PhD, Swanlund Endowed Chair of Physics at the University of Illinois at Urbana-Champaigne (UIUC), and Director of NASA Astrobiology Institute for Universal Biology at UIUC; and Thomas Kuhlman, PhD, a former Physics Professor at UIUC who is now at the University of California, Riverside, wondered why this is. "We thought a really simple thing to try was to just take one (retrotransposon) out of my genome and put it into the bacteria just to see what would happen," Dr. Kuhlman said. "And it turned out to be really quite interesting." Their results, published online on November 19, 2018 in PNAS, give more depth to the history of how advanced life may have emerged billions of years ago -- and could also help determine the possibility and nature of life on other planets. The title of the open-access PNAS article is “Testing the Retroelement Invasion Hypothesis for the Emergence of the Ancestral Eukaryotic Cell.”Along the way to explaining life, the researchers first encountered death -- bacterial death, that is. When they put retrotransposons in bacteria, the outcome was fatal. "As they jump around and make copies of themselves, they jump into genes that the bacteria need to survive," Dr. Kuhlman said. "It's incredibly lethal to them."

Good Nutrition Could Protect Children from Cognitive Difficulties Caused by Early-Life Stress

Good nutrition in early life may protect against stress-induced changes in brain development in young mice, according to data presented at the Society for Endocrinology 2018 Annual Conference in Glasgow (November 19-21). The study findings suggests that a nutrient-rich diet may have protective effects on brain development in young mice exposed to early-life stress, which reduces their risk of learning and memory issues in later life. It has been reported, in humans and animals, that exposure to adversities, such as stress, in early life can have long-lasting effects on brain function, and may lead to cognitive problems in later life. The period just after birth is critical for brain development and demand for nutrients is high, both for energy and as essential building blocks for the developing brain. Therefore any deficit in essential nutrients during this time could result in long-lasting abnormalities in brain function, including learning processes. The stress and metabolic processes of the body are closely interlinked, and whether stress-related cognitive problems in early life can be prevented or even reversed by ensuring good nutrition has not been fully investigated. In this study, Dr. Aniko Korosi and colleagues from the University of Amsterdam, investigated the effects of essential nutrients on brain function using a mouse model of early-life stress. Early-life stress was mimicked by reducing the amount of maternal care and attention given to pups within the first 2 weeks of birth. By the age of 4 months, these neglected mice show several impairments, including increased body fat levels, high stress hormone levels, and poor performance in learning and memory tasks.

Michael Bloomberg Gives Record $1.8 Billion to Johns Hopkins for Financial Aid--Historic Gift Is Largest Ever to a US College or University

Philanthropist, business leader, and three-term New York City Mayor Michael R. Bloomberg will commit a record-breaking $1.8 billion to support undergraduate financial aid at Johns Hopkins, the university announced on October 18, 2018, the largest-ever single contribution to a US college or university. "This historic gift reflects Mike Bloomberg's deep belief in the transformative power of higher education and his insistence that it be accessible to all qualified students, regardless of financial means," Johns Hopkins University President Ronald J. Daniels wrote in a message to the university community today (see text below). "It also affirms Mike's profound devotion to this university for the role that it played in enriching his life." Bloomberg, a 1964 Johns Hopkins graduate, announced his historic gift in a New York Times op-ed (https://www.nytimes.com/2018/11/18/opinion/bloomberg-college-donation-fi...) in which he identified college affordability as a national challenge. "America is at its best when we reward people based on the quality of their work, not the size of their pocketbook," Bloomberg said. "Denying students entry to a college based on their ability to pay undermines equal opportunity. It perpetuates inter-generational poverty. And it strikes at the heart of the American dream: the idea that every person, from every community, has the chance to rise based on merit." For more on Bloomberg's gift, read the full text of President Daniels' message to the community below. "Dear Members of the Johns Hopkins Community: