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Archive - Jul 2017


July 25th

Brain Disease in Former Football Players: 110 of 111 Deceased Former NFL Players Found to Show Signs of Chronic Traumatic Encephalopathy (CTE) in New Study; Significant CTE Also Found in Deceased Players from Lower Competitive Levels

Nearly every former National Football League (NFL) player (110 of 111) who played at least one regular season game and whose brain then was donated for research was diagnosed post-mortem with chronic traumatic encephalopathy (CTE). Among former college football players, those numbers were slightly less, at 91 percent. The findings of the largest CTE case series ever published, which appeared today (July 25, 2017) in the Journal of the American Medical Association (JAMA), suggest that CTE may be related to prior participation in football and that a long duration of play may be related to substantial disease burden. The article is titled “Clinicopathological Evaluation of Chronic Traumatic Encephalopathy in Players of American Football.” CTE is a progressive degenerative disease of the brain found in athletes and others with a history of repetitive brain trauma, including symptomatic concussions as well as asymptomatic sub-concussive hits to the head. Although the incidence and prevalence of CTE is unknown, it has been diagnosed in former amateur and professional contact sport athletes, as well as military veterans. Given the millions of contact sport athletes and military service members exposed to repetitive head impacts each year, CTE has become a major public health concern. Researchers from the VA Boston Healthcare System (VABHS) and the Boston University School of Medicine (BUSM) studied 202 deceased American football players whose brains were donated for research. They found CTE in 177 American football players across all levels of play (87 percent) including: 110 of 111 National Football League players (99 percent); 7 of 8 Canadian Football League (88 percent); 9 of 14 semi-professional players (64 percent); 48 of 53 college players (91 percent) and 3 of 14 high school players (21 percent).

Dodder Parasitic Plant Involved in Host Plant Alarm System; Host Plants Communicate Warning Signals Through Parasite Network When Insects Attack

Plants of the genus Cuscuta (dodder plants) have colorful folk names, such as wizard's net, devil's guts, strangle tare, or witch's hair. They are leaf- and root-less parasites and grow on their host plants without touching the soil. Their haustoria penetrate their host plants to extract water and nutrients. Dodder vines fuse their vascular systems with those of its host plants, connecting them with its network. A team of scientists led by Dr. Jianqiang Wu from the Kunming Institute of Botany in China and Dr. Ian Baldwin from the Max Planck Institute for Chemical Ecology in Jena have now taken a closer look at the ecological significance of dodder. They wanted to know whether the parasite is not only tapping the plants' supply system, but also playing a role in plant-plant communication. "It has been found that plants can communicate through volatile cues and underground mycorrhizal networks. We therefore wanted to know whether dodder can transmit insect-feeding-induced signals among different hosts and whether these signals can even activate defenses against insects," explains Dr. Jianqiang Wu, who worked at the Max Planck Institute for Chemical Ecology as a PhD student and later a project leader, and who is now heading a Max Planck Partner Group in China. In agriculture, dodder causes considerable economic damages in pasture farming with alfalfa and clover. In China, dodder parasitization leads to large losses in soybean yield. Therefore, the researchers used soybean plants for their experiments; but thale cress, tobacco, and wild tomato were also connected pairwise or in clusters with the parasite. In order to induce defense reactions, caterpillars of Spodoptera litura, a worldwide agricultural pest, were put on the plants.

July 24th

Exosome Diagnostics Completes $30 Million Series C Financing

Exosome Diagnostics Inc., a leader in the liquid biopsy market, today (July 24, 2017) announced the close of its $30 million Series C financing, led by insiders, Tiger Partners and Forbion Capital Partners. Blue Ridge Capital, NGN Capital, Arcus Ventures, b-to-v Partners, CD Ventures, and others participated in the round, which was oversubscribed. Exosome Diagnostics intends to use the funds to support the rapid commercial expansion of its ExoDx® Prostate(IntelliScore) and other diagnostic tests in the oncology market. The company will also continue to leverage its proprietary technologies for tests in other areas, such as neurodegenerative diseases, transplant rejection monitoring, and cardiology. Exosome Diagnostics will continue to invest in the expansion of its companion diagnostics (CDx) business and build out its exosomal instrumentation business by expanding its placement of units in the CDx market and continuing its point-of-care clinical development roadmap. These divisions and technology differentiators, such as one reaction RNA and cell-free DNA interrogation within its pipeline for signal enhancement, and its “Shahky” point-of-care instrumentation which is based on, sample in - answer out, protein biomarker interrogation capabilities, will further distinguish Exosome Diagnostics as the industry leader in the liquid biopsy space, the company believes. The preservation of Exosomes in the isolation process is essential, and will be vital for the derivation of highly specific and sensitive diagnostic tests. The company will also use the funds towards advancing its current technology platform capabilities and for the commercialization of its new technologies, such as its ability to isolate disease-specific exosomes based on tissue type.

"Molecular Archeology" Study of Over 7,000 Genes in 100 Species Generates New Phylogenetic Tree for Jawed Vertebrates

Using the largest and most informative molecular phylogenetic dataset ever analyzed, evolutionary biologists were able to construct a new phylogenetic tree of jawed vertebrates. This new tree resolves several key relationships that have remained controversial, including the identification of lungfishes as the closest living relatives of land vertebrates. The evolution of jawed vertebrates is part of our own history because humans belong to the tetrapods more specifically we are mammals, or, even more specifically, primates. The study utilized a novel set of newly developed analyses for building and reconstructing, large-scale genomic datasets. In the future, this method might also be used to reconstruct the evolutionary relationships among other enigmatic groups of organisms that await resolution. The research was done as part of a large collaborative work among several laboratories, with evolutionary biologists Dr. Iker Irisarri and Professor Axel Meyer from the University of Konstanz (Germany) among the principal investigators. Their research results were published online in Nature Ecology & Evolution on July 24, 2017. The article is titled “Phylotranscriptomic Consolidation of the Jawed Vertebrate Timetree.” Fishes, amphibians, mammals, snakes, turtles, lizards, crocodiles, and birds are all groups of animals that include thousands of species and are morphologically very different from each other. These animal lineages show huge differences in species richness, life history, behavior, and many other aspects of their biology. Notwithstanding these differences, these animals all possess a backbone and jaws. Since their origin about 470 million years ago, jawed vertebrates have diversified extraordinarily: they include more than 68,000 described species, not counting those that went extinct.

Beetle at “Dawn of the “Great Rise” Astonishes Entomologists and Paleontologists

He’s Australian, around half a centimeter long, fairly nondescript, 300 million years old – and he’s currently causing astonishment among both entomologists and paleontologists. The discovery of a beetle from the late Permian period (299 million to 251 million years ago), when even the dinosaurs had not yet appeared on the scene, is throwing a completely new light on the earliest developments in this group of insects. The reconstruction and interpretation of the characteristics of the beetle “Ponomarenkia belmonthensis” were achieved by Professor Dr. Rolf Georg Beutel and Dr. Evgeny V. Yan of Friedrich Schiller University Jena (Germany). They have published this discovery, together with renowned beetle researcher Dr. John Lawrence and Australian geologist Dr. Robert Beattie, online on Juy 21, 2017 in the Journal of Systematic Palaeontology. It was Dr. Beattie who discovered the only two known fossilized specimens of the beetle in former marshland in Belmont, Australia. The article is titled “At the Dawn of the Great Rise: Ponomarenkia belmonthensis (Insecta: Coleoptera), A Remarkable New Late Permian Beetle from the Southern Hemisphere.” “Beetles, which, with nearly 400,000 described species today, make up almost one-third of all known organisms, still lived a rather shadowy and cryptic existence in the Permian period,” explains Jena zoologist Dr. Beutel. “The fossils known to date have all belonged to an ‘ancestral’ beetle lineage, with species preferring narrow spaces under bark of coniferous trees.

July 23rd

Ribosomes Optimized for Autocatalytic Production; Theory Accurately Predicts Large-Scale Features, Revealing Why Ribosomes Are Made of Large Number of Unusually Small, Uniformly Sized Proteins, and a Few Strands of RNA That Vary Greatly in Size

Optimization for self-production may explain key features of ribosomes, the protein production factories of the cell, reported researchers from Harvard Medical School in Nature online on July 19, 2017. The article is titled “Ribosomes Are Optimized for Autocatalytic Production.” In a new study, a team led by Dr. Johan Paulsson, Professor of Systems Biology at Harvard Medical School, mathematically demonstrated that ribosomes are precisely structured to produce additional ribosomes as quickly as possible, in order to support efficient cell growth and division. The study's theoretical predictions accurately reflect observed large-scale features of ribosomes -- revealing why are they made of an unusually large number of small, uniformly sized proteins and a few strands of RNA that vary greatly in size -- and provide perspective on the evolution of an exceptional molecular machine. "The ribosome is one of the most important molecular complexes in all of life, and it's been studied across scientific disciplines for decades," Dr. Paulsson said. "I was always puzzled by the fact that it seemed like we could explain its finer details, but ribosomes have these bizarre features that have not often been addressed, or, if so, in an unsatisfying way." Every living cell, whether a single bacterium or a human neuron, is a biological system as dynamic and complex as any city. Contained within cells are walls, highways, power plants, libraries, recycling centers and much more, all working together in unison to ensure the continuation of life. The vast majority of these myriad structures are made of and made by proteins. And those proteins are made by ribosomes.

Evolutionary History of Salivary Protein (MUC7) Points to Possible Interbreeding Between Humans and a “Ghost” Species of Ancient Human; MUC7 May Also Be Key to Oral Microbiome Composition

In saliva, scientists have found hints that a "ghost" species of archaic humans may have contributed genetic material to ancestors of people living in Sub-Saharan Africa today. The research adds to a growing body of evidence suggesting that sexual rendezvous between different archaic human species may not have been unusual. Past studies have concluded that the forebears of modern humans in Asia and Europe interbred with other early hominin species, including Neanderthals and Denisovans. The new research is among more recent genetic analyses indicating that ancient Africans also had trysts with other early hominins. "It seems that interbreeding between different early hominin species is not the exception -- it's the norm," says Omer Gokcumen, PhD, an Assistant Professor of Biological Sciences in the University at Buffalo (UB) College of Arts and Sciences. "Our research traced the evolution of an important mucin protein called MUC7 that is found in saliva," he says. "When we looked at the history of the gene that codes for the protein, we see the signature of archaic admixture in modern day Sub-Saharan African populations." The research was published online on July 21, 2017 in Molecular Biology and Evolution. The study was led by Dr. Gokcumen and Stefan Ruhl, DDS, PhD, a professor of oral biology in UB's School of Dental Medicine. The open-access article is titled “Archaic Hominin Introgression in Africa Contributes to Functional Salivary MUC7 Genetic Variation.” The scientists came upon their findings while researching the purpose and origins of the MUC7 protein, which helps give spit its slimy consistency and binds to microbes, potentially helping to rid the body of disease-causing bacteria. As part of this investigation, the team examined the MUC7 gene in more than 2,500 modern human genomes.

July 22nd

Elephant Seals Recognize Each Other by Rhythm of Their Calls; Finding Is First for Non-Human Mammals

Every day, humans pick up on idiosyncrasies such as slow drawls, high-pitched squeaks, or hints of accents to put names to voices from afar. This ability may not be as unique as once thought, researchers report on July 20, 2017 in Current Biology. The open-access article is titled "Northern Elephant Seals Memorize the Rhythm and Timbre of Their Rivals' Voices." The scientists find that, unlike all other non-human mammals that have been studied, northern elephant seal males consider the spacing and timing of vocal pulses in addition to vocal tones when identifying the calls of their rivals. "This is the first natural example where on a daily basis, an animal uses the memory and the perception of rhythm to recognize other members of the population," says first author Dr. Nicolas Mathevon, of the Université de Lyon/Saint-Etienne in France. "There have been experiments with other mammals showing that they can detect rhythm, but only with conditioning." Over several years studying an elephant seal colony in Año Nuevo State Park, California, the researchers were able to recognize many of the individual animals just by the rhythm of their voices, he says. To test whether the elephant seals themselves made those distinctions in the same way, the researchers designed an experiment based on the social behavior of the colony's "beta males," who shy away upon hearing the call of a more powerful "alpha male," but ignore or confront other beta males and still-weaker "peripheral males." Upon hearing computer-modified alpha male calls with a sped-up or slowed-down tempo or a shifted pitch range, the beta males fled the scene if the alteration was minute enough to be within the individual variation of a particular alpha male's roar, but stayed put when confronted with more extreme changes.

Patch-Clamp Technique Extended to Intracellular Vesicles

Ion channels in the membrane vesicles that mediate intracellular protein transport play a crucial role in cell physiology. A method developed by a team at Ludwig-Maximilians-Universitaet (LMU) in Munich now allows these vesicles to be studied with greater specificity than ever before. Tiny membrane-bound vesicles known as endosomes and lysosomes serve as vehicles for the transport of protein cargoes within animal cells. Embedded in the vesicle membranes are proteins called ion channels, which control the passage of ions into and out of these intracellular organelles. Defects in these proteins play a central role in the pathogenesis of many diseases, and dissection of their molecular functions is vital for the development of effective therapies for these disorders. PD Christian Grimm and Professor Christian Wahl-Schott of the Department of Pharmacy (Director: Professor Martin Biel) at LMU Munich are among Europe's leading specialists in the use of the so-called “patch-clamp” technique for the study of ion channels in cell membranes. In the July 20, 2017 issue of Nature Protocols, these scientists and colleagues describe how they have adapted the method for use with endolysosomal vesicles. The Nature Protocols article is titled “Patch-Clamp Technique to Characterize Ion Channels in Enlarged Individual Endolysosomes.” In a second study, published in the July 20, 2017 issue of Cell Chemical Biology, the scientists go on to demonstrate how patch clamping can be applied to specific functional classes of transport vesicles. This article is titled “Small Molecules for Early Endosome-Specific Patch Clamping.” The work described in the to articles opens up entirely new perspectives for the characterization of ion channels and the mechanisms that regulate them.

Animal Model for Coffin-Siris Disorder May Provide Insights into Genetic Bases of Some Neuropsychiatric Disorders

A study by scientists at the Children’s Medical Center Research Institute at University of Texas Southwestern (CRI) is providing insight into the genetic basis of neuropsychiatric disorders. In this research, the first mouse model of a mutation in the arid1b gene was created and then used to show that growth hormone treatments reverse some manifestations of the mutation. The ARID1B gene is one of the most commonly mutated genes in patients with intellectual disability and autism spectrum disorders, but scientists have not yet discerned if and how defects in the ARID1B gene contribute to these clinical manifestations. To understand how reduced levels of the protein product of the gene might cause these disorders, a team of researchers led by Hao Zhu, MD (photo) and including graduate student Cemre Celen genetically modified mice to carry a mutation in one of two copies of the arid1b gene. This mutation replicates the genetics of Coffin-Siris syndrome, a disorder that some patients with defects in the ARID1B gene have that is characterized by speech and social development problems, intellectual disability, and delayed physical growth. The hope is that by understanding the molecular basis of Coffin-Siris syndrome, scientists will gain a deeper understanding of more common diseases involving intellectual and social impairment. Scientists found mice with the mutated arid1b gene exhibited the same type of physical and social changes seen in children with Coffin-Siris syndrome, such as abnormal brain development, muscle weakness, and increased anxiety and fear. The mice also displayed features consistent with autism spectrum disorder, such as social interaction abnormalities, repetitive behaviors, and abnormal “squeaks” or vocalizations.