Geological processes that formed Oregon’s Painted Hills and Colorado Plateau ‘witnessed’

Date:
July 2, 2015

Source:
University of Oregon

Summary:
Geologists have seen ridges and valleys form in real time and — even though the work was a fast-forwarded operation done in a laboratory setting — they now have an idea of how climate change may impact landscapes.

 

 

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Graphic shows how the combination of hill-slope erosion and precipitation-generated runoff over geological time create a landscape of orderly ridges and valleys.
Credit: Courtesy of Joshua Roering

 

 

University of Oregon geologists have seen ridges and valleys form in real time and — even though the work was a fast-forwarded operation done in a laboratory setting — they now have an idea of how climate change may impact landscapes.

On a basic-science front, the findings, which appear in the July 3 issue of the journal Science, provide a long-sought answer to why some landscape features appear so orderly, with distinct and evenly spaced valleys and ridges.

Picture the Painted Hills near John Day, Oregon, the Colorado Plateau, the badlands of Montana and South Dakota, and even portions of the Coastal Range between Eugene and Florence, Oregon. These watersheds are masterpieces that nature has formed over geological timescales, said the UO’s Joshua J. Roering.

The regularity of hill and valley landforms, he said, is reached after a long tug-of-war between erosion driven by runoff, which influences how rivers cut their paths in valley floors, and soil movement on hillsides caused by disturbances from such things as burrowing gophers, tree roots, digging ants and frost.

The National Science Foundation-funded project (EAR 1252177) is part of a growing effort in geomorphology — the study of the origin and evolution of many landscape features — to understand how soil processes at work on hillsides compete with water runoff in the formation of valley floors.

Put simply, runoff processes carve valleys while soil movement on hill slopes tends to fill them. The relative vigor of these competing forces determines the spacing of hills and valleys and the degree of drainage dissection. “Hill-slope processes help determine valley density and the way valleys and ridges form,” Roering said. “These networks are climate dependent.”

Over the course of five 20-hour experiments conducted in small sandboxes, UO doctoral student Kristin E. Sweeney, the study’s lead author, extruded crystalline silica to represent uplift due to tectonic forces. To induce erosion, she used mist from 42 nozzles to create precipitation-driven runoff and 625 blunt needles that fired periodic bursts of large water drops to mimic natural disturbances that occur on hill slopes. Each experiment showed how the processes, acting together, converted flat plains into ridges and valleys.

“In our experiments we were able to dictate the processes involved and observe the landscapes that arise,” Sweeney said. “We were able to directly control the various processes. Previous research has only attempted to replicate channel processes — what the rivers do. We essentially started from scratch, working to see the movement of sediment slopes in a realistic way.

“Ridges and valleys are part of a fundamental landscape pattern that people easily recognize,” she said. “From an airplane, you look down and you see watersheds, you see valleys, and they tend to have very regular spacing. Explaining this pattern is a fundamental question in geomorphology.”

The study’s three-member team also included Christopher Ellis, senior research associate at the University of Minnesota’s St. Anthony Falls Laboratory where the experiments were conducted. The team spent more than a year developing a workable methodology to study the sediment transfer processes.

The study confirms earlier work using mathematical computations and actual landscape measurements by Taylor Perron of the Massachusetts Institute of Technology and published in the journal Nature in July 2009. The UO study provides the first physical documentation of the processes involved.

“The contribution of hill slopes to drainage basin formation has not been widely appreciated,” Roering said. “The more water on landscapes, the more vegetation, the more varmints and more life that is out there doing hill slope work. If you make things drier you tend to decrease the vigor of hill-slope processes and drainage networks should reflect that.”

Further information and animations:http://blogs.uoregon.edu/ksweeney/research/


Story Source:

The above post is reprinted from materials provided by University of Oregon. The original item was written by Jim Barlow. Note: Materials may be edited for content and length.


Journal Reference:

  1. K. E. Sweeney, J. J. Roering, C. Ellis. Experimental evidence for hillslope control of landscape scale. Science, 2015 DOI:10.1126/science.aab0017

 

Source: University of Oregon. “Ridges and valleys: Experiments open window on landscape formation: Geological processes that formed Oregon’s Painted Hills and Colorado Plateau ‘witnessed’.” ScienceDaily. ScienceDaily, 2 July 2015. <www.sciencedaily.com/releases/2015/07/150702151302.htm>.

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Seeing is believing

Date:
July 1, 2015

 

Source: 
Harvard Medical School

 

Summary: 
Researchers have uncovered key principles about the way vision-neurons work, explaining how the brain uses sensory information to guide the decisions that drive behaviors.

 

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Experiments tested detection of changes in direction of motion (left-hand pathway) or depth (right-hand pathway, in blue) after neurons in V2/V3 were inactivated.
Credit: Born lab

 

 

If your eyes deceive you, blame your brain. Many optical illusions work because what we see clashes with what we expect to see.

That 3D movie? Give credit to filmmakers who exploit binocular vision, or the way the brain merges the slightly different images from the two eyes to create depth.

These are examples of the brain making sense of the information coming from the eyes in order to produce what we “see.” The brain combines signals that reach your retina with the models your brain has learned to predict what to expect when you move through the world. Your brain solves problems by inferring what is the most likely cause of any given image on your retina, based on knowledge or experience.

Individual tuning

Scientists have explored the complex puzzle of visual perception with increasing precision, discovering that individual neurons are tuned to detect very specific motions: up, but not down; right, but not left; and in all directions. These same neurons, which live in the brain’s middle temporal visual area, are also sensitive to relative depth.

Now a Harvard Medical School team led by Richard Born has uncovered key principles about the way those neurons work, explaining how the brain uses sensory information to guide the decisions that underlie behaviors. Their findings, reported in Neuron, illuminate the nature and origin of the neural signals used to solve perceptual tasks.

Based on their previous work, the researchers knew that they could selectively interfere with signals concerning depth, while leaving the signals for direction of motion intact. They wanted to learn what happened next, after the visual information was received and used to make a judgment about the visual stimulus.

Was the next step based on “bottom-up” information coming from the retina as sensory evidence? Or, as in optical illusions, did top-down information originating in the brain’s decision centers influence what happened in response to a visual stimulus?

“We were able to show that there’s a direct bottom-up contribution to these signals,” said Born, HMS professor of neurobiology and senior author of the paper. “It’s told us some very interesting things about how the brain makes calculations and combines information from different sources, and how that information influences behaviors.”

Selective blocking

In their experiments with nonhuman primates, the researchers cooled specific neurons to temporarily block their signals, in the same way that ice makes a sprained ankle feel better because it prevents pain neurons from firing.

The team selectively blocked pathways that provide information about visual depth–how far something is from the viewer–but not the direction of motion. The animals were trained to watch flickering dots on a screen, something like “snow” on an old television, and detect when the dots suddenly lined up and moved in one direction or changed in depth.

If the animal detected motion or a change in depth, making an eye movement to look at the changed stimulus would result in delivery of a reward.

When the neurons were inactivated, the animals were less likely to detect depth, but their ability to detect motion was not affected. This told the scientists that feed-forward information, not feedback, was being used by the animal to make its decision. Their findings help explain how relative motion and depth work together.

Two pathways

“Combining two pathways that compute two different things in the same neurons is essential for vision, we think,” Born said. “But for these two particular calculations, first you have to compute them separately before you can put them together.”

Born believes there are other implications of their work.

“We think that the same operations that are happening in the visual system are happening at higher levels of the brain, so that by understanding these circuits that are easier to study we think we will gain traction on those higher level questions,” Born said.

This work was supported by the Sackler Scholarship, Quan Fellowship, the Natural Sciences and Engineering Research Council of Canada, National Eye Institute grant R01 EY11379 and the Core Grant for Vision Research EY12196.


Story Source:

The above post is reprinted from materials provided by Harvard Medical School. The original item was written by Elizabeth Cooney. Note: Materials may be edited for content and length.


Journal Reference:

  1. Alexandra Smolyanskaya, Ralf M. Haefner, Stephen G. Lomber, Richard T. Born. A Modality-Specific Feedforward Component of Choice-Related Activity in MT. Neuron, 2015; 87 (1): 208 DOI:10.1016/j.neuron.2015.06.018

 

Source: Harvard Medical School. “How brains make sense of the visual world: Seeing is believing.” ScienceDaily. ScienceDaily, 1 July 2015. <www.sciencedaily.com/releases/2015/07/150701123348.htm>.

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Date:
June 30, 2015

Source:
University of Washington

Summary:
Researchers have produced cell-to-cell communication in baker’s yeast — a first step in learning to build multicellular organisms or artificial organs from scratch.

 

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UW researchers have produced cell-to-cell communication in baker’s yeast, a first step in building multicellular organisms from scratch. The red yeast cells produce a plant hormone, which “tells” the green cells to express a gene differently.
Credit: University of Washington

 

 

For centuries, humans have been playing with yeast. But these simple fungal cells usually do their jobs — making bread rise or converting sugar into alcohol — without having to communicate or work together.

Now, a team of University of Washington researchers has engineered yeast cells (Saccharomyces cerevisiae) that can “talk” to one another, using a versatile plant hormone called auxin.

In a paper published June 23 in the American Chemical Society’s journal ACS Synthetic Biology, the researchers describe a novel cell-to-cell communication system that enables one yeast cell to regulate the expression of genes and influence the behavior of an entirely separate yeast cell.

It’s a basic step in understanding the communication and cooperative processes that might lead to synthetic stem cells that could grow into artificial organs or organisms that require different types of cells to work together.

“Until you can actually build a multicellular organism that starts from a single cell, you don’t really understand it. And until we can do that, it’s going to be hard to do things like regrow a kidney for someone who needs it,” said senior author Eric Klavins, a UW associate professor of electrical engineering and of bioengineering.

It might also enable engineered yeast to perform complicated behaviors that coordinated multicellular systems such as our immune system can pull off, like recognizing an invading pathogen and mounting a response. If so, one might program those cells to collaboratively diagnose the flu or malaria: just add saliva to a packet of yeast and see if it changes color.

For now, though, the team spearheaded by lead authors Arjun Khakhar, a UW doctoral student in bioengineering, and Nicholas J. Bolten, a UW doctoral student in electrical engineering, simply wanted to see if it could induce one yeast cell to send a signal that sets off a cascade of changes in another cell.

In the initial experiment, they used the plant hormone auxin — which yeast cells don’t normally recognize or respond to — to “turn off” a target gene in another cell. In this case, the gene that was switched off was an inserted jellyfish gene that turned the yeast fluorescent green.

“This project was to find out whether we could use auxin to make the cells talk to each other in a really simple way,” said Klavins. “We’re not sending complicated messages yet. One cell is saying ‘hello?’ and the other cell says ‘I can hear you.’ Eventually they’ll say ‘I’m this kind of cell. What are you? Let’s work together.’ But for now it’s pretty much ‘hi.'”

Synthetic biologists, who assemble genetic parts in new ways with the goal of popping them into an organism to produce reliable behaviors, have struggled to build modules that enable cell-to-cell communication in organisms that don’t naturally do it.

The UW team overcame this hurdle by engineering a suite of novel transcription factors — proteins that control whether a specific gene inside a cell’s DNA is expressed or not — with varying sensitivities to auxin. That “tunability” offers important control in regulating cell behavior.

With co-author and UW associate biology professor Jennifer Nemhauser, the UW team figured out how to make a “sender” yeast cell produce auxin, a versatile hormone that controls everything from where a plant’s roots develop to how effectively they fight off pathogens. Through trial and error, the team learned an enzyme borrowed from a soil bacterium can induce yeast to convert a commonly available chemical into auxin.

In the “receiver” yeast cells, the researchers inserted the new transcription factor — which was assembled from so many different genetic parts that they call it the “Frankenfactor” — and engineered it to activate the jellyfish gene that turned the cell green.

When the sender cell released auxin, additional proteins that the researchers introduced in the receiver cell were able to degrade the Frankenfactor and switch off the gene that turned the receiver cell green.

That type of simple communication forms the bedrock of multicellular organisms in which different types of cells collaborate to carry out complicated tasks. As a next step, the UW team plans to test whether auxin can induce more complex behaviors in yeast cells, such as forming patterns or cooperatively computing basic functions.

Since auxin is a plant hormone, mammalian cells also ignore it, making auxin a potentially useful tool in designing gene therapies or other applications without adverse reactions in humans. The UW method, which uses a “guide RNA” to target the gene of interest, could be adapted to produce a number of genetic or behavior changes.

“If you ask someone in computer science what they can do with a programming language, they’ll laugh and say they can do anything with it,” Klavins said. “If we can figure out the programming language of life, we can do anything that life does — except in a more controllable, reliable way.”

The research was funded by the National Science Foundation and the Paul Allen Family Foundation.


Story Source:

The above post is reprinted from materials provided by University of Washington. The original item was written by Jennifer Langston. Note: Materials may be edited for content and length.


Journal Reference:

  1. Arjun Khakhar, Nicholas J. Bolten, Jennifer Nemhauser, Eric Klavins.Cell-cell communication in yeast using auxin biosynthesis and auxin responsive CRISPR transcription factors. ACS Synthetic Biology, 2015; 150623113028004 DOI: 10.1021/acssynbio.5b00064

 

Source: University of Washington. “Scientists program solitary yeast cells to say ‘hello’ to one another.” ScienceDaily. ScienceDaily, 30 June 2015. <www.sciencedaily.com/releases/2015/06/150630141710.htm>.

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Date:
June 29, 2015

Source:
University of Maryland Medical Center/School of Medicine

Summary:
As the South Korean MERS outbreak continues, researchers have discovered and validated two therapeutics that show early promise in preventing and treating the disease, which can cause severe respiratory symptoms, and has a death rate of 40 percent.

 

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The South Korean MERS outbreak began last month when a traveler returned from Saudi Arabia, and infected many people before officials realized he had the disease. So far, around 180 people have been infected in South Korea, and nearly 30 have died.
Credit: © gwolters / Fotolia

 

 

As the South Korean epidemic of Middle East Respiratory Syndrome (MERS) continues unabated, researchers have raced to find treatments for the deadly virus, which has killed more than 400 people since it was first discovered three years ago in Saudi Arabia.

Now, scientists at the University of Maryland School of Medicine and Regeneron Pharmaceuticals, Inc., have discovered and validated two therapeutics that show early promise in preventing and treating the disease, which can cause severe respiratory symptoms, and has a death rate of 40 percent. These therapeutics are the first to succeed in protecting and treating animal models of the MERS virus. The study appears in the journalProceedings of the National Academy of Sciences (PNAS).

“While early, this is very exciting, and has real potential to help MERS patients,” says a lead researcher on the study, Matthew B. Frieman, PhD, an assistant professor of microbiology and immunology at the University of Maryland School of Medicine (UM SOM). “We hope that clinical study will progress on these two antibodies to see whether they can eventually be used to help humans infected with the virus.”

The two antibodies, REGN3051 and REGN3048, showed an ability to neutralize the virus. This research, done in collaboration with Regeneron, a biopharmaceutical company based in Tarrytown, New York, used several of the company’s proprietary technologies to search for and validate effective antibodies targeting the virus.

MERS was first discovered in 2012 in Saudi Arabia. It appears that the disease spread to humans from camels, who may themselves been infected by bats. Research has shown that it is similar to Severe acute respiratory syndrome (SARS); both are caused by Coronaviruses, both cause respiratory problems, and both are often fatal.

The paper also announced the development a novel strain of mice, which will help scientists understand the disease and look for treatments. This work relied on Regeneron’s VelociGene technology to create partially humanized mice that can be infected with MERS.

“Mice are typically not susceptible to MERS,” said Prof. Frieman, who is an expert on both MERS and SARS, as well as other emerging viruses. “This new mouse model will significantly boost our ability to study potential treatments and help scientists to understand how the virus causes disease in people.”

The South Korean outbreak began last month when a traveler returned from Saudi Arabia, and infected many people before officials realized he had the disease. So far, around 180 people have been infected in South Korea, and nearly 30 have died.

“Prof. Frieman’s work provides the first glimmer of hope that we can treat and cure this threatening virus,” said Dean E. Albert Reece, MD, PhD, MBA, who is also the vice president for Medical Affairs, University of Maryland, and the John Z. and Akiko K. Bowers Distinguished Professor and Dean of the School of Medicine. “I know that they will continue to work hard to see whether these compounds can take the next steps to clinical trials.”


Story Source:

The above post is reprinted from materials provided by University of Maryland Medical Center/School of Medicine. Note: Materials may be edited for content and length.


Journal Reference:

  1. Kristen E. Pascal, Christopher M. Coleman, Alejandro O. Mujica, Vishal Kamat, Ashok Badithe, Jeanette Fairhurst, Charleen Hunt, John Strein, Alexander Berrebi, Jeanne M. Sisk, Krystal L. Matthews, Robert Babb, Gang Chen, Ka-Man V. Lai, Tammy T. Huang, William Olson, George D. Yancopoulos, Neil Stahl, Matthew B. Frieman, and Christos A. Kyratsous.Pre- and postexposure efficacy of fully human antibodies against Spike protein in a novel humanized mouse model of MERS-CoV infection. PNAS, June 2015 DOI: 10.1073/pnas.1510830112

 

Source: University of Maryland Medical Center/School of Medicine. “First-ever possible treatments for MERS; two promising candidates.” ScienceDaily. ScienceDaily, 29 June 2015. <www.sciencedaily.com/releases/2015/06/150629162650.htm>.

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Target Health Featured in Profile Magazine

 

Below is an extract of an article in Profile Magazine that featured Target Health. The article in its entirety can be found at (http://profilemagazine.com/2015/target-health/). Notice Malcom Furlow’s Armani Indian in the background picture of the article.

 

Champion of Paperless Health Care: Independent thinking has paid off for Target Health’s Jules Mitchel, whose company has revolutionized the clinical trial process –By Amy Martino in Profile Magazine

Target Health is not your average contract research organization. In fact, it’s an “e-CRO.“ Key to becoming a player in the brave new e-world was Target Health’s development of its own suite of patented software and its championing of the paperless clinical trial. “I was always an independent thinker, but it was not always appreciated within large organizations,“ says president and cofounder Jules Mitchel. “No matter where I worked, even in smaller companies, I had a gut feeling I could do it better.“

Mitchel’s pharmaceutical industry experience includes work at Wyeth and Pfizer, as well as a background in research, which has informed his current role. “Basic research allowed me to express my passion for learning and to develop problem-solving and analytical skills, no matter what the problem,“ Mitchel says. “It also taught me how to experiment and to appreciate serendipitous findings, and not to be fearful of new knowledge and changing direction once there is an ?aha’ moment.“

The most important skill Mitchel honed in his early years, however, was patience. “I used to do aging studies that took three years to do,“ he says. “Things take time. A lot of people in business are not patient enough, so they make silly decisions.“

Patience came in handy when Target Health was cofounded in 1993 by Mitchel and his wife and CEO, Joyce Hays. “I have an MBA and a PhD and all that stuff, but it’s not the same as the real world of actually running a company,“ Mitchel says of the “reality check“ involved in guiding a company. In addition to generating business and hiring the right people, Mitchel had to adapt his leadership style. “When you have your own company, you have to balance empathy and concern about your employees, but also demonstrate a level of firmness, and you have to develop that,“ Mitchel says. “Not easy.“

 

Glorious Roan Sunset – Another Masterpiece by James Farley

 

From James: “Sunset from Jane Bald, facing Round Bald, with blooming Rhododendrons in view. This photo is a dream come true for me!

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©JFarley Photography 2015

 

ON TARGET is the newsletter of Target Health Inc., a NYC-based, full-service, contract research organization (eCRO), providing strategic planning, regulatory affairs, clinical research, data management, biostatistics, medical writing and software services to the pharmaceutical and device industries, including the paperless clinical trial.

 

For more information about Target Health contact Warren Pearlson (212-681-2100 ext. 104). For additional information about software tools for paperless clinical trials, please also feel free to contact Dr. Jules T. Mitchel or Ms. Joyce Hays. The Target Health software tools are designed to partner with both CROs and Sponsors. Please visit the Target Health Website.

 

Joyce Hays, Founder and Editor in Chief of On Target

Jules Mitchel, Editor

 

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Ancient Man Had a Neanderthal Great-Great Grandfather and You Have Neanderthal DNA

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Analysis of the jawbone of a man who lived about 40,000 years ago reveals the closest direct descendant of a Neanderthal who mated with a modern 1) ___. Scientists know that modern humans and Neanderthals lived together in Europe and occasionally 2) ___. A modern human who lived in eastern Europe between 37,000 and 42,000 years ago had at least one Neanderthal ancestor as little as four generations back – which is to say, a great-great-grandparent.

 

Scientists have known for at least half a decade that living humans bear traces of Neanderthal blood – or more specifically, Neanderthal DNA. Just when and where our ancestors bred with their now-extinct cousins, however, has been tricky to pin down until now. A new study published last week in the journal Nature has the highest percentage of Neanderthal 3) ___ of any modern human ever studied. “We were lucky to hit upon an individual like this,“ says study co-author Svante Paabo of the Max Planck Institute for Evolutionary Anthropology in Leipzig. The specimen, known as Oase 1, consists only of a male jawbone, and from the moment it was discovered in 2002 its shape suggested that it might belong to a hybrid between Homo 4) ___ and Neanderthal. Those claims have remained controversial, but the new analysis lays the controversy to rest. “It’s really stunning,“ says Oxford’s Tom Higham, an expert on the Neanderthal-human transition who was not involved in this research. Part of what stuns Higham is the genomic artistry it took to tease useful genetic information out of the tiny DNA samples lead author Qiaomei Fu of Harvard Medical School and her team were able to extract from the 5) ___. “We tried to do this in 2009 and failed,“ says Paabo. His lab has been working since then to improve their techniques, with resounding success. The genome they sequenced from the samples was incomplete, but it was enough for the scientists to conclude that between 6% and 9% of Oase 1’s genome is Neanderthal in origin. People living today have 4% at most. That difference is more significant than it might seem. “We found seven huge pieces of chromosomes that seemed to be purely of 6) ___ origin,“ says Paabo. That means pieces had to come from a relatively recent ancestor, since they hadn’t yet been broken up by the reshuffling that happens in each generation as parents’ chromosomes combine.

 

 

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This jawbone from a 40,000-year-old modern human shows some Neanderthal features – and DNA now confirms he had a Neanderthal ancestor as few as four generations back. Photograph By Svante Paabo, Max Planck Institute For Evolutionary Anthropology

 

The non-Neanderthal genome sequences, meanwhile, show that Oase 1 isn’t related to humans living today. His genealogical line died out at some point. This analysis represents a biotechnological tour de force, but it also puts paleoanthropologists a step closer to fully answering to what Higham calls the $64,000 question: What happened to wipe out the Neanderthals, and when? Genomic analysis of a 45,000-year-old human thigh bone last year suggested that humans and Neanderthals interbred in what is now Siberia sometime between 50,000 and 60,000 years ago – an extremely imprecise number, and a very broad conclusion. “The great breakthrough here,“ Higham says, “is the ability to say ?this specific person had a Neanderthal great-great-grandfather.’ That puts a human timescale on it.“ If scientists can figure out when 7) ___ took place in different parts of Europe and the Middle East, they’ll be able to say in detail just how rapidly humans spread across these regions, how long they were in contact with Neanderthals. An analysis of a first draft of the Neanderthal genome by the Max Planck Institute team, led by Svante Paabo, released in May 2010, indicates interbreeding probably occurred.“Those of us who live outside 8) ___ carry a little Neanderthal DNA in us,“ said Paabo, who led the study. “The proportion of Neanderthal-inherited genetic material is about 1 to 4%. It is a small but very real proportion of ancestry in non-Africans today,“ says Dr. David Reich of Harvard Medical School, who worked on the study. This research compared the 9) ___ of the Neanderthals to five modern humans from China, France, sub-Saharan Africa, and Papua New Guinea. The finding is that about 1 to 4 percent of the genes of the non-Africans came from Neanderthals, compared to the baseline defined by the two Africans. This indicates a gene flow from Neanderthals to modern humans, i.e., interbreeding between the two populations. Since the three non-African genomes show a similar proportion of Neanderthal sequences, the interbreeding must have occurred early in the migration of modern humans out of Africa, perhaps in the 10) ___ East. No evidence for gene flow in the direction from modern humans to Neanderthals was found. Gene flow from modern humans to Neanderthals would not be expected if contact occurred between a small colonizing population of modern humans and a much larger resident population of Neanderthals. A very limited amount of interbreeding could explain the findings, if it occurred early enough in the colonization process. Sources; National Geographic; Wikipedia; Nature; Wall Street Journal

 

ANSWERS: 1) human; 2) mated; 3) DNA; 4) sapiens; 5) jawbone; 6) Neanderthal; 7) interbreeding; 8) Africa; 9) genome; 10) Middle

 

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Paleogenetics – Svante Paabo (1955 to Present)

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Svante Paabo

 

Svante Paabo (born 20 April 1955) is a Swedish biologist specializing in evolutionary genetics. One of the founders of paleogenetics, a discipline that uses the methods of genetics to study early humans and other ancient populations, he has worked extensively on the Neanderthal genome. Paabo was born in Stockholm and grew up with his mother, Estonian chemist Karin Paabo. His father, biochemist Sune Bergstrom, who shared the Nobel Prize in Physiology or Medicine with Bengt I. Samuelsson and John R. Vane in 1982.

 

Paabo earned his PhD from Uppsala University in 1986. Since 1997, he has been director of the Department of Genetics at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. In 1997, Paabo and colleagues reported their successful sequencing of Neanderthal mitochondrial DNA (mtDNA), originating from a specimen found in Feldhofer grotto in the Neander valley. In August 2002, Paabo’s department published findings about the “language gene“, FOXP2, which is lacking or damaged in some individuals with language disabilities, and in 2006, Paabo announced a plan to reconstruct the entire genome of Neanderthals. In 2007, he was named one of Time magazine’s 100 most influential people of the year.

 

In February 2009, at the Annual Meeting of the American Association for the Advancement of Science (AAAS) in Chicago, it was announced that the Max Planck Institute for Evolutionary Anthropology had completed the first draft version of the Neanderthal genome. Over 3 billion base pairs were sequenced in collaboration with the 454 Life Sciences Corporation. This project, led by Paabo, has shed new light on the recent evolutionary history of modern humans. Paabo and his coworkers also published a report in 2010 about the DNA analysis of a finger bone found in the Denisova Cave in Siberia; the results suggest that the bone belonged to an extinct member of the genus Homo that had not yet been recognized, the Denisova hominin. In May 2010, Paabo and his colleagues published a draft sequence of the Neanderthal genome in the journal Science. He and his team also concluded that there was probably interbreeding between Neanderthals and Eurasian (but not African) humans. There is growing support in the scientific community for this theory of admixture between archaic and anatomically-modern humans, though some archeologists remain skeptical about this conclusion.

 

In 2014, Paabo published the book Neanderthal Man: In Search of Lost Genomes where he, in the mixed form of a memoir and popular science, tells the story of the research effort to map the Neanderthal genome combined with thought on human evolution.

 

In terms of awards, in 1992, Paabo received the Gottfried Wilhelm Leibniz Prize of the Deutsche Forschungsgemeinschaft, which is the highest honor awarded in German research. Paabo was also elected a member of the Royal Swedish Academy of Sciences in 2000. In October 2009 the Foundation For the Future announced that Paabo had been awarded the 2009 Kistler Prize for his work isolating and sequencing ancient DNA, beginning in 1984 with a 2,400-year-old mummy. Also, in June 2010 the Federation of European Biochemical Societies awarded him the Theodor Bucher Medal for outstanding achievements in Biochemistry and Molecular Biology, and in 2013, he received Gruber Prize in Genetics for ground breaking research in evolutionary genetics. In June 2015 he was awarded an honorary doctor of science degree from NUI Galway.

 

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Study of Ebola Survivors Opens in Liberia to Examine Long-Term Health Effects of Ebola Virus Disease

 

Congratulations to our colleagues at NIAID.

 

The Liberia-U.S. clinical research partnership known as PREVAIL has launched a study of people in Liberia who have survived Ebola virus disease (EVD) within the past two years. The study investigators hope to better understand the long-term health consequences of EVD, determine if survivors develop immunity that will protect them from future Ebola infection, and assess whether previously EVD-infected individuals can transmit infection to close contacts and sexual partners. The study, sponsored by the Ministry of Health of Liberia and the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, will take place at various sites in Liberia and is expected to enroll approximately 7,500 people, including 1,500 people of any age who survived EVD and 6,000 of their close contacts. Participants who test positive for HIV infection during the course of the study will be counseled and referred to treatment in accordance with standard medical practice in Liberia.

 

Study participants will undergo a medical history and physical and vision examination and have blood samples collected so researchers can identify and track any health issues, monitor organ and ocular function and record Ebola antibody levels. Some participants may also be asked to provide samples of bodily fluids, such as sweat, tears, and for adults, semen or cervical secretions. Participants will be asked if they would like to identify up to five close contacts (household members at the time of Ebola diagnosis and sexual partners after recovery from Ebola virus disease). Close contacts who agree to participate in the study will undergo a physical examination, have blood samples taken, and asked to complete a questionnaire detailing their contact with the Ebola survivor, such as touching, sleeping in the same bed and intimate relations. Staff from the NIH’s National Eye Institute have helped establish a new eye clinic at John F. Kennedy Medical Hospital, where ophthalmologists from NEI and Johns Hopkins will be evaluating study participants and their identified close contacts for visual problems. Treatment will be provided by Liberian ophthalmologists partnering in the study. There have been reports of inflammatory eye disease and vision loss among Ebola survivors and one goal of the study is to determine the incidence and extent of Ebola-related eye disease among survivors, risk factors contributing to its development, and optimal treatment strategies.

 

The research team will follow the Ebola survivors and their close contacts for up to five years with study visits occurring every six months. At each follow-up visit, participants will undergo a physical examination and additional blood draws, to allow study physicians to monitor and characterize any changes in Ebola antibody levels and to detect the presence of select medical conditions. This information will help to determine the evolution of Ebola antibodies and will provide insight on whether survivors can still transmit the virus and if so, whether these people get sick with Ebola virus disease. Using data collected at these site visits, the researchers will calculate the incidence, prevalence and risk factors for various health issues experienced by survivors, such as vision problems; immune system changes; mental disorders; joint pain; diabetes; hypertension; and pregnancy complications. Close contacts will be used as a control group to assess whether the risks of these conditions are the same or different from those who have not had Ebola virus disease.

 

PREVAIL, or the Partnership for Research on Ebola Virus in Liberia, is a clinical research partnership between the U.S. Department of Health and Human Services and the Liberian Ministry of Health. The new study, an Ebola natural history study known as PREVAIL III, is one of three research projects launched by the partnership. In February 2015, PREVAIL initiated two other Ebola clinical studies. PREVAIL I is a clinical trial to assess the safety and efficacy of two experimental vaccines to prevent Ebola virus infection. A total of 1,500 participants continue to be followed in the Phase 2 segment of this study. PREVAIL II is a clinical trial designed to obtain safety and efficacy data on various investigational drugs for the treatment of Ebola virus disease. The trial is ongoing in Liberia, Sierra Leone and the United States Additional information about the PREVAIL III Ebola natural history study is available at ClinicalTrials.gov using the identifier NCT02431923. For more information about NIAID’s Ebola research, visit the NIAID Ebola webpage.

 

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Efficacy of Handwashing with Soap and Nail Clipping on Intestinal Parasitic Infections in School-Aged Children

 

Intestinal parasitic infections are highly endemic among school-aged children in resource-limited settings. To lower their impact, preventive measures should be implemented that are sustainable with available resources. As a result, a study, published online in Pols Medicine (9 June 2015), was performed to assess the impact of handwashing with soap and nail clipping on the prevention of intestinal parasite reinfections.

 

In this trial, 367 parasite-negative school-aged children (aged 6-15 years of age) were randomly assigned to receive both, one or the other, or neither of the interventions in a 2×2 factorial design. Assignment sequence was concealed. After 6 months of follow-up, stool samples were examined using direct, concentration, and Kato-Katz methods. Hemoglobin levels were determined using a HemoCue spectrometer. The primary study outcomes were prevalence of intestinal parasite reinfection and infection intensity. The secondary outcome was anemia prevalence. Analysis was by intention to treat. Main effects were adjusted for gender, age, drinking water source, latrine use, pre-treatment parasites, handwashing with soap and nail clipping at baseline, and the other factor in the additive model.

 

Results showed that 14% of the children in the handwashing with soap intervention group were reinfected versus 29% in the groups with no handwashing with soap. Similarly, 17% of the children in the nail clipping intervention group were reinfected versus 26% in the groups with no nail clipping. Also, following the intervention, 13% of the children in the handwashing group were anemic versus 23% in the groups with no handwashing with soap. The prevalence of anemia did not differ significantly between children in the nail clipping group and those in the groups with no nail clipping.

 

According to the authors, handwashing with soap at key times and weekly nail clipping significantly decreased intestinal parasite reinfection rates. Furthermore, the handwashing intervention significantly reduced anemia prevalence in children. The authors noted that the intensive follow-up and monitoring during this study made it such that the assessment of the observed intervention benefits was under rather ideal circumstances, and hence the study could possibly overestimate the effects when compared to usual conditions. It was proposed that the next step should be implementing pragmatic studies and developing more effective approaches to promote and implement handwashing with soap and nail clipping at larger scales.

 

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FDA Approves New Antiplatelet Drug Used During Heart Procedure

 

According to the Centers for Disease Control and Prevention, percutaneous coronary intervention (PCI) is performed on approximately 500,000 people in the United States each year. For this procedure, the coronary arteries are opened by inflating a balloon at the site of the narrowing, usually followed by placement of a small mesh tube, called a stent, to keep the artery open.

 

The FDA has approved Kengreal (cangrelor), an intravenous antiplatelet drug that prevents formation of harmful blood clots in the coronary arteries, the blood vessels that supply blood to the heart. It is approved for adult patients undergoing PCI. By preventing platelets from accumulating, Kengreal reduces the risk of serious clotting complications related to the procedure, including heart attack and clotting of the stent (stent thrombosis). As with other FDA-approved anti-platelet drugs, bleeding, including life-threatening bleeding, is the most serious risk of Kengreal.

 

In a clinical trial that compared Kengreal to Plavix (clopidogrel) in more than 10,000 participants, Kengreal significantly reduced the occurrence of heart attack, the need for further procedures to open the artery and stent thrombosis. However, the overall occurrence of serious bleeding was low but more common with Kengreal than with clopidogrel. Approximately one in every 170 Kengreal patients had a serious bleed versus approximately one in every 275 clopidogrel patients.

 

Kengreal is manufactured by The Medicines Company based in Parsippany, New Jersey.

 

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