July 28, 2016
University of British Columbia
New research suggests evolution is a driving mechanism behind plant migration, and that scientists may be underestimating how quickly species can move.
New research from the University of British Columbia suggests evolution is a driving mechanism behind plant migration, and that scientists may be underestimating how quickly species can move.
The study, published today in the journal Science, builds on previous research that has shown some plants and animals are moving farther north or to higher altitudes in an effort to escape rising global average temperatures due to climate change.
“We know from previous research that evolution might play a role in how fast a species can move across a region or continent,” said Jennifer Williams, the study’s lead author and an assistant professor in UBC’s department of geography. “But what our study suggests is that evolution is not only a factor in movement, but that it can, in fact, accelerate the spread, and can do so predictably.”
For the study, researchers used a small flowering plant (Arabidopsis thaliana), a common model organism in plant biology, to test the role of evolution in plant migration. Individual plants with different traits were cultivated together to create two sets of populations, one in which evolution was acting and another in which evolution was stopped.
They found that, after six generations, evolving plant populations dispersed seeds and migrated 11 per cent farther than non-evolving populations in landscapes with favourable conditions. Meanwhile, in landscapes where conditions were more challenging for the plants to disperse seeds, the evolving plant populations spread 200 per cent farther.
The findings suggest that evolution accelerates the speed of migration, said Williams.
However, more research is needed to determine why the researchers saw a larger effect of evolution under the more challenging conditions, which in this case increased the speed of movement.
“We know, for example, that there are some species of butterflies and plants that are expanding their ranges with climate change and moving north or up in elevation,” she said. “What our results suggest is that, with evolution, the species can move faster and faster because the traits that make them better at moving are becoming more common at the front of the invasion. In the case of our plants, in the evolving populations, their seeds can disperse a bit further.”
Williams said the findings underscore the importance for scientists to account for evolutionary change when predicting how quickly native species will be able to move as the Earth’s climate continues to warm.
The study was co-authored by Bruce Kendall of the University of California, Santa Barbara, and Jonathan Levine of the ETH Zurich.
- J. L. Williams, B. E. Kendall, J. M. Levine. Rapid evolution accelerates plant population spread in fragmented experimental landscapes.Science, 2016; 353 (6298): 482 DOI: 10.1126/science.aaf6268
Source: University of British Columbia. “Evolution drives how fast plants could migrate with climate change.” ScienceDaily. ScienceDaily, 28 July 2016. <www.sciencedaily.com/releases/2016/07/160728155005.htm>.
Relationship between decadal variations in temperatures in the Pacific and the tropopause identified
July 26, 2016
Helmholtz Centre for Ocean Research Kiel (GEOMAR)
In the late 20th century scientists observed a cooling at the transition between the troposphere and stratosphere at an altitude of about 15 kilometers. Climate scientists now show that the cooling could also be part of a natural decadal variation which is controlled by the water temperature of the Pacific.
Water plays a major role for our planet not only in its liquid form at the surface. In the atmosphere too, it considerably affects our lives as well as weather and climate. Clouds and rainfall are one example. Water vapor, the gaseous form of water, also plays a prominent role on Earth. It is the most important greenhouse gas in the atmosphere, without it the Earth would be a frozen planet. For climate variations, water vapor is particularly important in the stratosphere at altitudes between 15 and 50 kilometers. How much of the gas actually reaches the stratosphere mainly depends on the temperature at the transition between the lowest atmospheric layer, the troposphere, and the overlying stratosphere. This boundary layer is called the tropopause.
Now scientists of the GEOMAR Helmholtz Centre for Ocean Research Kiel, together with a colleague from Bergen (Norway), were able to demonstrate for the first time that natural fluctuations in water temperatures of the Pacific — which occur on decadal timescales — are directly related to the temperature of the tropical tropopause. “It has long been thought that human influences already affected the tropopause. However, it seems that natural variability is still the dominating factor,” says Dr. Wuke Wang from GEOMAR, lead author of the study just published in the international journal Scientific Reports.
For their study, the researchers used observations for the period 1979-2013 and also climate models. “We were thus able to extend the study period to nearly 150 years. The model allows us to easily look at both human and natural influences and to separate their impacts from each other,” explains Prof. Dr. Katja Matthes, climate researcher at GEOMAR and co-author of the study.
A well-known climatic phenomenon is the so-called Pacific Decadal Oscillation (PDO). “This natural variation with decadal timescale leads to anomalously high or low water temperatures of the Pacific,” explained Dr. Wang. The PDO influences the climate and ecosystems in the Pacific region and also the global mean temperature of the Earth.
The model simulations show that the fluctuations in water temperatures also affect the wind systems over the tropical and subtropical Pacific. This in turn also alters the air transport between the lower and upper layers of the troposphere, ultimately regulating the temperatures at the boundary to the stratosphere. “We were now able to demonstrate these relationships for the first time,” said Dr. Wang.
Thus, the current study contradicts earlier hypotheses about the temperature variability of the tropical tropopause. As early as in the late 20th century, scientists had seen a cooling trend there which began in the 1970s. They traced this observation back to anthropogenic causes, in particular the increase in greenhouse gases. “However, this assumption was based on a rather patchy data base and simplified climate models. Our study shows that the cooling of the tropical tropopause does not have to be a one-way street but could also be part of a natural fluctuation which extends over several decades,” Professor Matthes emphasized.
This knowledge is also of paramount importance for the general climate research. The temperature of the tropopause decides on the input of water vapor into the stratosphere: The higher the water vapor content in the stratosphere, the higher the increase in surface temperatures. Anthropogenic climate change also has an effect on the temperature of the tropopause, and this effect could become more evident in the coming decades. “Only if we can clearly distinguish natural variability from anthropogenic influences, we can make reliable forecasts for the future development of our climate,” Prof. Matthes summarizes.
- Wuke Wang, Katja Matthes, Nour-Eddine Omrani, Mojib Latif. Decadal variability of tropical tropopause temperature and its relationship to the Pacific Decadal Oscillation. Scientific Reports, 2016; 6: 29537 DOI:10.1038/srep29537
Source: Helmholtz Centre for Ocean Research Kiel (GEOMAR). “Decade-long cooling cycle: Middle atmosphere in sync with ocean: Relationship between decadal variations in temperatures in the Pacific and the tropopause identified.” ScienceDaily. ScienceDaily, 26 July 2016. <www.sciencedaily.com/releases/2016/07/160726123630.htm>.
July 26, 2016
German Primate Center
Our hands are highly developed grasping organs that are in continuous use. Long before we stir our first cup of coffee in the morning, our hands have executed a multitude of grasps. Directing a pen between our thumb and index finger over a piece of paper with absolute precision appears as easy as catching a ball or operating a doorknob. Now neuroscientists have studied how the brain controls the different grasping movements. In their research with rhesus macaques, it was found that the three brain areas that are responsible for planning and executing hand movements, perform different tasks within their neural network.
Our hands are highly developed grasping organs that are in continuous use. Long before we stir our first cup of coffee in the morning, our hands have executed a multitude of grasps. Directing a pen between our thumb and index finger over a piece of paper with absolute precision appears as easy as catching a ball or operating a doorknob. The neuroscientists Stefan Schaffelhofer and Hansjörg Scherberger of the German Primate Center (DPZ) have studied how the brain controls the different grasping movements.
In their research with rhesus macaques, it was found that the three brain areas AIP, F5 and M1 that are responsible for planning and executing hand movements, perform different tasks within their neural network. The AIP area is mainly responsible for processing visual features of objects, such as their size and shape. This optical information is translated into motor commands in the F5 area. The M1 area is ultimately responsible for turning this motor commands into actions. The results of the study contribute to the development of neuroprosthetics that should help paralyzed patients to regain their hand functions.
The three brain areas AIP, F5 and M1 lay in the cerebral cortex and form a neural network responsible for translating visual properties of an object into a corresponding hand movement. Until now, the details of how this “visuomotor transformation” are performed have been unclear. During the course of his PhD thesis at the German Primate Center, neuroscientist Stefan Schaffelhofer intensively studied the neural mechanisms that control grasping movements. “We wanted to find out how and where visual information about grasped objects, for example their shape or size, and motor characteristics of the hand, like the strength and type of a grip, are processed in the different grasp-related areas of the brain,” says Schaffelhofer.
For this, two rhesus macaques were trained to repeatedly grasp 50 different objects. At the same time, the activity of hundreds of nerve cells was measured with so-called microelectrode arrays. In order to compare the applied grip types with the neural signals, the monkeys wore an electromagnetic data glove that recorded all the finger and hand movements. The experimental setup was designed to individually observe the phases of the visuomotor transformation in the brain, namely the processing of visual object properties, the motion planning and execution. For this, the scientists developed a delayed grasping task. In order for the monkey to see the object, it was briefly lit before the start of the grasping movement. The subsequent movement took place in the dark with a short delay. In this way, visual and motor signals of neurons could be examined separately.
The results show that the AIP area is primarily responsible for the processing of visual object features. “The neurons mainly respond to the three-dimensional shape of different objects,” says Stefan Schaffelhofer. “Due to the different activity of the neurons, we could precisely distinguish as to whether the monkeys had seen a sphere, cube or cylinder. Even abstract object shapes could be differentiated based on the observed cell activity.”
In contrast to AIP, area F5 and M1 did not represent object geometries, but the corresponding hand configurations used to grasp the objects. The information of F5 and M1 neurons indicated a strong resemblance to the hand movements recorded with the data glove. “In our study we were able to show where and how visual properties of objects are converted into corresponding movement commands,” says Stefan Schaffelhofer. “In this process, the F5 area plays a central role in visuomotor transformation. Its neurons receive direct visual object information from AIP and can translate the signals into motor plans that are then executed in M1. Thus, area F5 has contact to both, the visual and motor part of the brain.”
Knowledge of how to control grasp movements is essential for the development of neuronal hand prosthetics. “In paraplegic patients, the connection between the brain and limbs is no longer functional. Neural interfaces can replace this functionality,” says Hansjörg Scherberger, head of the Neurobiology Laboratory at the DPZ. “They can read the motor signals in the brain and use them for prosthetic control. In order to program these interfaces properly, it is crucial to know how and where our brain controls the grasping movements.” The findings of this study will facilitate to new neuroprosthetic applications that can selectively process the areas’ individual information in order to improve their usability and accuracy.
- Stefan Schaffelhofer, Hansjörg Scherberger. Object vision to hand action in macaque parietal, premotor, and motor cortices. eLife, 2016; 5 DOI: 10.7554/eLife.15278
Source: German Primate Center. “From vision to hand action: Neuroscientists decipher how our brain controls grasping movements.” ScienceDaily. ScienceDaily, 26 July 2016. <www.sciencedaily.com/releases/2016/07/160726094220.htm>.
July 25, 2016
Researchers have developed a new index based on rib and body weight measurements that predicts whether a mammal lived on land, in water, or both. When applied to extinct mammalian species, the index showed that some could not have supported their own weight while walking or crawling, and thus must have been restricted to an aquatic life. The index reveals the habitats of extinct species and enables reconstruction of their lifestyles and the anatomical changes that accompanied adoption of an exclusively aquatic lifestyle.
Despite the extensive fossil record of mammals, it is often difficult to use fossil data to reconstruct the lifestyles and habitats of extinct species. The fact that some species spent all or part of their time underwater, respectively similar to modern-day whales and seals, further complicates this.
Konami Ando and Shin-chi Fujiwara, researchers at Nagoya University, addressed this by developing a new index for predicting if a species lived its entire life in the water. The index is based on how the ribs must be relatively strong for an animal to walk or crawl over land, but not for it to swim. After establishing the index via measurements of living terrestrial, semiaquatic, and exclusively aquatic species, Ando and Fujiwara used it to predict that some extinct species could not have supported themselves on land.
Although mammals originally evolved as terrestrial organisms, cladistics shows that some returned to aquatic lives, and that this sometimes occurred independently. Examples include whales, dolphins, and manatees, which never leave the water, and seals and hippopotamuses, which split time between land and water. Studies of fossils of extinct species also suggest some species spent all or some of their time in the water. However, inability to use fossil records alone to determine a species’ lifestyle has made this hard to confirm.
In their study, reported in the Journal of Anatomy, Ando and Fujiwara analyzed rib cages and their resistance to vertical compression in a range of mammalian species. This important factor represents an animal’s ability to support its body weight against gravity while walking or crawling; a trait aquatic organisms do not need. The researchers investigated 26 modern-day terrestrial, semiaquatic, and exclusively aquatic species, including the killer whale, polar bear, dugong, giraffe, and hippopotamus. They used their data to establish an index for differentiating between groups with different habitats. They then applied the index to four extinct mammalian species, all of which had retained their four limbs but showed signs of having been partially or completely aquatic, to shed light on their potential lifestyles.
“We selected mammals with different habitats from a range of taxa and analyzed fossils for which the bones in the thoracic region were well-preserved,” Fujiwara says. “We focused on the fracture loads of ribs. We found the sum of the fracture loads of all true ribs directly connected to the sternum divided by the body weight effectively separated the extant species groups by habitat. Exclusively aquatic species were clearly differentiated.”
After establishing that the index could correctly classify living species with known habitats and lifestyles, the researchers applied it to extinct groups:Ambulocetus, an early ancestor of whales, and three desmostylian species, which are the keens of elephants and sea cows. This was to confirm or reject earlier hypotheses about these groups’ lifestyles, which were based on other morphological findings.
“Our index lets us conclude that Ambulocetus and two desmostylians (Paleoparadoxia and Neoparadoxia) could not have supported themselves on land; they were exclusively aquatic,” Ando says. “But the findings were inconclusive for the third desmostylian (Desmostylus). We may need to perform additional studies on the intermediate group of semiaquatic species, include a bone density variable in our model, or improve our data on the body mass of extinct species to refine the index.”
The new index should help in both reconstructing the lifestyles and habitats of extinct mammals and clarifying anatomical changes associated with mammals shifting to a life partly or exclusively in the water.
- Konami Ando, Shin-ichi Fujiwara. Farewell to life on land – thoracic strength as a new indicator to determine paleoecology in secondary aquatic mammals. Journal of Anatomy, 2016; DOI:10.1111/joa.12518
Source: Nagoya University. “New index reveals likelihood of terrestrial or aquatic lifestyles of extinct mammals.” ScienceDaily. ScienceDaily, 25 July 2016. <www.sciencedaily.com/releases/2016/07/160725105228.htm>.
Linville Falls as Viewed at the Bottom of Linville Gorge – Great Place to Cool Off
Note from James Farley, colleague and photographer extraordinaire: Difficult day, as it was raining and there was thunder and lightning, while we hiked on the Plunge Basin Trail. Caught a brief moment, when the rain stopped, to get some stillness to the slower-moving water, and get a clear view through the water. Shot on my Canon 5D Mark III and 35mm f1.4 2nd Generation lens. 2 second exposure at f16 and ISO50. Lee Filters 0.6 ND Grad and Landscape Circular Polarizer used.
Linville Falls as Viewed at the Bottom of Linville Gorge ©JFarley Photography
Advice from the NIH: Summer is here and it’s blazing hot! So Please Stay Cool
It is important to be aware of the health risks that higher temperatures can bring. Older adults and people with chronic medical conditions are particularly susceptible to hyperthermia and other heat-related illnesses. Knowing the signs and recognizing the dangers to avoid problems is essential. The National Institute on Aging (NIA), part of the National Institutes of Health, offers advice to help combat the dangers of hot weather.
Heat fatigue, heat syncope (sudden dizziness after prolonged exposure to the heat), heat cramps, heat exhaustion and heat stroke are forms of hyperthermia, which is caused by a failure of the body’s heat-regulating mechanisms to deal with a hot environment. The combination of individual lifestyle, general health, and high temperatures can increase older adults’ risk for heat-related problems. Lifestyle factors can include not drinking enough fluids, living in housing without air conditioning, lack of mobility and access to transportation, overdressing, visiting overcrowded places and not understanding how to respond to hot weather conditions. On hot and humid days, older people, particularly those with chronic medical conditions like heart disease and diabetes, should stay indoors in cooler spaces, especially during an air pollution alert. People without air conditioners should go to places that do have air conditioning, such as senior centers, shopping malls, movie theaters and libraries. Cooling centers, which may be set up by local public health agencies, religious groups and social service organizations in many communities, are another option.
There are many things that can increase risk for hyperthermia, including:
Dehydration; Age-related changes to the skin such as poor blood circulation and inefficient sweat production; use of multiple medications; reduced sweating caused by medications such as diuretics, sedatives, tranquilizers and certain heart and blood pressure drugs; high blood pressure or other health conditions that require changes in diet; people on salt-restricted diets may be at increased risk, however, salt pills should not be used without first consulting a doctor; heart, lung and kidney diseases, as well as any illness that causes general weakness or fever; being substantially overweight or underweight; and alcohol use.
Heat stroke is a life-threatening form of hyperthermia. It occurs when the body is overwhelmed by heat and unable to control its temperature. Signs and symptoms of heat stroke include a significant increase in body temperature (generally above 104 degrees Fahrenheit), mental status changes (like confusion or combativeness), strong rapid pulse, dry flushed skin, lack of sweating, feeling faint, staggering or coma. It is critical to seek immediate emergency medical attention for a person with heat stroke symptoms, especially an older adult.
For more information about Target Health contact Warren Pearlson (212-681-2100 ext. 165). 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
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Impressive Immune System Discoveries
Maps of the lymphatic system: old (left) and updated to reflect UVA’s discovery.
Credit: University of Virginia Health System; ScienceDaily.com
In a discovery that overturns decades of textbook teaching, researchers at the University of Virginia School of Medicine have determined that the 1) ___ is directly connected to the immune system by vessels previously thought not to exist. That such vessels could have escaped detection when the lymphatic system has been so thoroughly mapped throughout the body is surprising on its own, but the true significance of the discovery lies in the effects it could have on the study and treatment of neurological diseases ranging from autism to Alzheimer’s disease to multiple sclerosis. Instead of asking, ‘How do we study the immune response of the brain?’ And, ‘Why do multiple sclerosis patients have the immune attacks?’ now we can approach this mechanistically. Because the brain is like every other tissue connected to the peripheral 2) ___ through meningeal lymphatic vessels, said Jonathan Kipnis, PhD, professor in the UVA Department of Neuroscience and director of UVA’s Center for Brain Immunology and Glia (BIG). It changes entirely the way we perceive the neuro-immune interaction. We always perceived it before as something esoteric that can’t be studied. But now we can ask mechanistic questions. We believe that for every neurological disease that has an immune component to it, these vessels may play a major role, Kipnis said. Hard to imagine that these vessels would not be involved in a [neurological] disease with an immune component.
New Discovery in Human Body
Kevin Lee, PhD, chairman of the UVA Department of Neuroscience, described his reaction to the discovery by Kipnis’ lab: The first time these guys showed me the basic result, I just said one sentence: ?They’ll have to change the textbooks.’ There has never been a lymphatic system for the central 3) ___ system, and it was very clear from that first singular observation — and they’ve done many studies since then to bolster the finding — that it will fundamentally change the way people look at the central nervous system’s relationship with the immune system. Even Kipnis was skeptical initially. I really did not believe there are structures in the body that we are not aware of. I thought the body was mapped, he said. I thought that these discoveries ended somewhere around the middle of the last 4) ___. But apparently they have not. The discovery was made possible by the work of Antoine Louveau, PhD, a postdoctoral fellow in Kipnis’ lab. The vessels were detected after Louveau developed a method to mount a mouse’s meninges — the membranes covering the brain — on a single slide so that they could be examined as a whole. It was fairly easy, actually, he said. There was one trick: We fixed the meninges within the skullcap, so that the tissue is secured in its physiological condition, and then we dissected it. If we had done it the other way around, it wouldn’t have worked. After noticing vessel-like patterns in the distribution of immune 5) ___ on his slides, he tested for lymphatic vessels and there they were. The impossible existed. The soft-spoken Louveau recalled the moment: I called Jony [Kipnis] to the microscope and I said, ?I think we have something.’
As to how the brain’s lymphatic vessels managed to escape notice all this time, Kipnis described them as very well hidden and noted that they follow a major 6) ___ vessel down into the sinuses, an area difficult to image. It’s so close to the blood vessel, you just miss it, he said. If you don’t know what you’re after, you just miss it. Live imaging of these vessels was crucial to demonstrate their function, and it would not be possible without collaboration with Tajie Harris, Kipnis noted. Harris, a PhD, is an assistant professor of neuroscience and a member of the BIG center. Kipnis also saluted the phenomenal surgical skills of Igor Smirnov, a research associate in the Kipnis lab whose work was critical to the imaging success of the study. The unexpected presence of the lymphatic vessels raises a tremendous number of questions that now need answers, both about the workings of the brain and the diseases that plague it. For example, take Alzheimer’s disease. In Alzheimer’s, there are accumulations of big 7) ___ chunks in the brain, Kipnis said. We think they may be accumulating in the brain because they’re not being efficiently removed by these vessels. He noted that the vessels look different with age, so the role they play in aging is another avenue to explore. And there’s an enormous array of other neurological diseases, from autism to multiple sclerosis, that must be reconsidered in light of the presence of something science insisted did not exist.
Interesting Developments Based on the Initial Discovery
In a startling discovery (discussed above) that raises fundamental questions about human behavior, researchers at the University of Virginia School of Medicine have determined, based on their research last year, that the immune system directly affects — and even controls — creatures’ social behavior, such as their desire to interact with others. So could immune system problems contribute to an inability to have normal social interactions? The answer appears to be yes, and that finding could have great implications for neurological conditions such as autism-spectrum disorders and schizophrenia.
The brain and the adaptive immune system were thought to be isolated from each other, and any immune activity in the brain was perceived as sign of a pathology. And now, not only are we showing that they are closely interacting, but some of our behavior traits might have evolved because of our immune response to pathogens, explained Jonathan Kipnis, PhD, chairman of UVA’s Department of Neuroscience. It’s crazy, but maybe we are just multicellular battlefields for two ancient forces: pathogens and the immune system. Part of our personality may actually be dictated by the immune system.
Evolutionary Forces at Work
The follow-up finding is equally illuminating, shedding light on both the workings of the brain and on evolution itself. The relationship between people and pathogens, the researchers suggest, could have directly affected the development of our social behavior, allowing us to engage in the social interactions necessary for the survival of the species while developing ways for our immune systems to protect us from the diseases that accompany those interactions. Social behavior is, of course, in the interest of8) ___, as it allows them to spread. The UVA researchers have shown that a specific immune molecule, interferon gamma, seems to be critical for social behavior and that a variety of creatures, such as flies, zebrafish, mice and rats, activate interferon gamma responses when they are social. Normally, this molecule is produced by the immune system in response to bacteria, viruses or parasites. Blocking the molecule in mice using genetic modification made regions of the brain hyperactive, causing the mice to become less social. Restoring the molecule restored the brain connectivity and behavior to normal. In a paper outlining theirfindings, the researchers note the immune 9) ___ plays a profound role in maintaining proper social function.
It’s extremely critical for an organism to be social for the survival of the species. It’s important for foraging, sexual reproduction, gathering, hunting, said Anthony J. Filiano, PhD, Hartwell postdoctoral fellow in the Kipnis lab and lead author of the study. So the hypothesis is that when organisms come together, you have a higher propensity to spread infection. So you need to be social, but [in doing so] you have a higher chance of spreading pathogens. The idea is that interferon gamma, in evolution, has been used as a more efficient way to both boost social behavior while boosting an anti-pathogen response.
The researchers note that a malfunctioning immune system may be responsible for social deficits in numerous neurological and psychiatric disorders. But exactly what this might mean for autism and other specific conditions requires further investigation. It is unlikely that any one molecule will be responsible for disease or the key to a cure, the researchers believe; instead, the causes are likely to be much more complex. But the discovery that the immune system — and possibly germs, by extension — can control our interactions raises many exciting avenues for scientists to explore, both in terms of battling neurological disorders and understanding human 10) ___. Immune molecules are actually defining how the brain is functioning. So, what is the overall impact of the immune system on our brain development and function? Kipnis said. I think the philosophical aspects of this work are very interesting, but it also has potentially very important clinical implications. Kipnis and his team worked closely with UVA’s Department of Pharmacology and the group of Vladimir Litvak, PhD, at the University of Massachusetts Medical School. Litvak’s team developed a computational approach to investigate the complex dialogue between immune signaling and brain function in health and disease. Using this approach we predicted a role for interferon gamma, an important cytokine secreted by T lymphocytes, in promoting social brain functions, Litvak said. Our findings contribute to a deeper understanding of social dysfunction in neurological disorders, such as autism and schizophrenia, and may open new avenues for therapeutic approaches.
Source: University of Virginia School of Medicine; University of Massachusetts Medical School; NIH.gov; ScienceDaily.com
- Antoine Louveau, Igor Smirnov, Timothy J. Keyes, Jacob D. Eccles, Sherin J. Rouhani, J. David Peske, Noel C. Derecki, David Castle, James W. Mandell, Kevin S. Lee, Tajie H. Harris, Jonathan Kipnis. Structural and functional features of central nervous system lymphatic vessels. Nature, 2015; DOI: 10.1038/nature14432
- The findings have been published online in the journal Nature. The article was written by Filiano, Yang Xu, Nicholas J. Tustison, Rachel L. Marsh, Wendy Baker, Igor Smirnov, Christopher C. Overall, Sachin P. Gadani, Stephen D. Turner, Zhiping Weng, Sayeda Najamussahar Peerzade, Hao Chen, Kevin S. Lee, Michael M. Scott, Mark P. Beenhakker, Litvak and Kipnis.
This work was supported by the National Institutes of Health (grants No. AG034113, NS081026 and T32-AI007496) and the Hartwell Foundation.
ANSWERS: 1) brain; 2) system; 3) nervous; 4) century; 5) cells; 6) blood; 7) protein; 8) pathogens; 9) molecule; 10) behavior
Emil Adolf von Behring MD: Antitoxins and Passive Serum Therapy
Emil Adolf von Behring MD (1854-1917)
Source: Public Domain, Wikimedia Commons.org
One of the most important pieces of evidence to support the earlier theory of antibodies came from Emil von Behring, who received the first-ever Nobel Prize in Medicine, in 1901. His Nobel Prize medal is now kept on display at the International Red Cross and Red Crescent Museum in Geneva.
Emil von Behring and his colleagues discovered in 1890 that animals, when injected with tiny, weakened doses of the bacteria that cause tetanus or diphtheria, produce chemicals in their blood that neutralize these microbes’ disease-causing toxins. Not only that, but von Behring established that transferring blood containing these antitoxin chemicals to other animals granted them immunity from the same disease. As opposed to ?active’ immunity, that is, the defense provided by a host’s immune system, receiving these antitoxins from another animal was said to provide ?passive immunity’. Taking this a stage further, von Behring showed that children injected with antitoxin-containing serum were cured of their diphtheria symptoms, and did not die of the disease. This was a hugely important discovery: the vaccines created by Jenner and Pasteur prevented diseases, but von Behring’s discoveries showed how a disease that had already taken hold could be cured. Von Behring was hailed as a savior of children and of soldiers, and the mass-produced form of his serum saved tens of thousands of lives every year in his native Germany alone. Unfortunately, this method of treatment – passive serum therapy – turned out to be useful for only a limited number of diseases. However, anyone who has ever received an anti-venom injection for snakebites has benefited directly from von Behring’s discoveries.
The achievements of von Behring, and of Metchnikov and Ehrlich, helped to establish a brand-new field of science called immunology, one that sought to explore the mysterious workings of the body’s inner defense mechanisms. And once anti-toxins had provided convincing experimental proof for Ehrlich’s antibodies, scientists rushed to investigate these toxin-neutralizing molecules in greater detail. Many diseases are caused by microorganisms, but the body can use its immune system to defend itself against attacks and become immune to new attacks. As part of its defenses, the immune system forms antibodies that neutralize poisons, or toxins, that are formed by bacteria. Emil von Behring and other researchers showed that by means of blood plasma, or serum, antibodies could be transferred from one person or animal to another person, who also then became immune. In 1900 Emil von Behring introduced serum from immune horses as a method to cure and prevent diphtheria.
Emil Adolf von Behring (15 March 1854 – 31 March 1917) was a German physiologist, born in Hansdorf, now Lawice, IIawa County, Poland. Between 1874 and 1878, he studied medicine at the Akademie fur das militararztliche Bildungswesen, Berlin. He was mainly a military doctor and then became Professor of Hygienics within the Faculty of Medicine at the University of Marburg (against the initial strenuous opposition of the faculty council), a position he would hold for the rest of his life. He and the pharmacologist Hans Horst Meyer had their laboratories in the same building, and Behring stimulated Meyer’s interest in the mode of action of tetanus toxin. Behring was the discoverer of diphtheria antitoxin in 1890 and attained a great reputation by that means and by his contributions to the study of immunity. He won the first Nobel Prize in Physiology or Medicine in 1901 for the development of serum therapies against diphtheria (which Kitasato Shibasaburo and Emile Roux also contributed to) and tetanus. Diphtheria had been a scourge of the population, especially children, whereas tetanus was a leading cause of death in wars, killing the wounded. He was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1902. At the International Tuberculosis Congress in 1905 he announced that he had discovered a substance proceeding from the virus of tuberculosis. This substance, which he designated T C, plays the important part in the immunizing action of Professor Behring’s bovivaccine, which prevents bovine tuberculosis. He tried unsuccessfully to obtain a protective and therapeutic agent for humans. His diphtheria serum was developed by repeatedly injecting the deadly toxin into a horse. The serum was used effectively during an epidemic in Germany. A chemical company preparing to undertake commercial production and marketing of the diphtheria serum offered him a contract.
In December 1896, Behring married the then eighteen-year-old Else Spinola, who was a daughter of Bernhard Spinola, the director of the Charite hospital in Berlin, and a Jewish-born mother who had converted to Christianity upon her marriage. They had six sons. They held their honeymoon at villa Behring on Capri 1897, where Behring owned a vacation home. In 1909-1911, the Russian writer Maxim Gorky lived at this villa. Behring died at Marburg, Hessen-Nassau, on 31 March 1917. His name survived with: the Dade Behring, organization, at the time, the world’s largest company dedicated solely to clinical diagnostics, (now part of the Siemens Healthcare Division), in CSL Behring, a manufacturer of plasma-derived biotherapies, in Behringwerke AG in Marburg, in Novartis Behring and in the Emil von Behring Prize of the University of Marburg, the highest endowed medicine award in Germany.
Sources: Nobelprize.org; Wikipedia
Advances in Possible Treatments for Gaucher and Parkinson’s Diseases
Gaucher disease affects an estimated 1 in 50,000 to 1 in 100,000 people in the general population. People of Eastern and Central European (Ashkenazi) Jewish heritage are more likely to get Gaucher disease. Parkinson’s disease affects 1.5-2% of people over age 60, and the incidence increases with age. In the United States, about 60,000 new cases are identified each year. Parkinson’s disease affects more than 1 million people in North America and 7-10 million people worldwide.
Gaucher disease occurs when GBA1, the gene that codes for the protein glucocerebrosidase, is mutated. This protein normally helps cells dispose of certain fats (lipids), a type of waste produced by all cells. When a person inherits two mutated copies of GBA1, lipids accumulate and can cause symptoms such as enlargement of the spleen, frequent bleeding and bruising, weakened bones and, in the most severe cases, neurological disease. People with even one mutated copy of GBA1 are at higher risk of developing Parkinson’s disease, a common disorder characterized by tremors, muscular rigidity and slowed movements.
According to an article published on line (12 June 2016) in the Journal of Neuroscience, with assistance from a high tech robot known at Tox21, National Institutes of Health researchers have identified and tested a molecule that shows promise as a possible treatment for Gaucher disease and Parkinson’s disease.
To better understand the connection between Gaucher and Parkinson’s diseases, the authors used a labor-intensive technology to develop pluripotent stem cells (unspecialized cells that can develop into various specialized body cells). The stem cells were created in the lab from the skin cells of Gaucher patients with and without Parkinson’s disease. The stem cells were then converted into neurons that had features that were identical to those in people with Gaucher disease. Results showed that the neurons from Gaucher patients, who also had Parkinson’s disease, had elevated levels of alpha-synuclein. This is the protein that accumulates in the brains of people with Parkinson’s disease impacting neurons responsible for controlling movement.
The authors then looked for a molecule that would help patients with mutant GBA1 break down cellular waste. In a process known as high-throughput drug screening, the authors used the Tox21 robot to evaluate hundreds of thousands of different molecules. The authors identified a promising molecule, NCGC607which helps to chaperone the mutated protein so that it can still function. In the patients’ stem cell-derived neurons, NCGC607 reversed the lipid accumulation and lowered the amount of alpha-synuclein, suggesting a possible treatment strategy for Parkinson’s disease.
Daniel Kastner, M.D., Ph.D., NHGRI scientific director and director of the institute’s Division of Intramural Research said that This research constitutes a major advance as it demonstrates how insights from a rare disorder such as Gaucher disease can have direct relevance to the treatment of common disorders like Parkinson’s disease. the authors will next test the new molecule to see if it might be developed into an appropriate prototype drug for patients with Gaucher disease and Parkinson’s disease.
Brain Circuits that Help People Cope with Stress
People encounter stressful situations and stimuli everywhere, every day, and studies have shown that long-term stress can contribute to a broad array of health problems. However, some people cope with stress better than others, and scientists have long wondered why.
According to a study published online (19 July 2016) in the Proceedings of the National Academy of Sciences, brain patterns in humans have been identified that appear to underlie resilient coping. Resilient coping encompasses the healthy emotional and behavioral responses to stress that help some people handle stressful situations better than others.
In a study of human volunteers, the authors used a brain scanning technique called functional magnetic resonance imaging (fMRI) to measure localized changes in brain activation during stress. Study participants were given fMRI scans while exposed to highly threatening, violent and stressful images followed by neutral, non-stressful images for six minutes each. While conducting the scans, the authors also measured non-brain indicators of stress among study participants, such as heart rate, and levels of cortisol, a stress hormone, in blood.
The brain scans revealed a sequence of three distinct patterns of response to stress, compared to non-stress exposure. The first pattern was characterized by sustained activation of brain regions known to signal, monitor and process potential threats. The second response pattern involved increased activation, and then decreased activation, of a circuit connecting brain areas involved in stress reaction and adaptation, perhaps as a means of reducing the initial distress to a perceived threat. The third pattern helped predict those who would regain emotional and behavioral control to stress. This pattern involved what the authors described as neuroflexibility, in a circuit between the brain’s medial prefrontal cortex and forebrain regions including the ventral striatum, extended amygdala, and hippocampus during sustained stress exposure. The authors explained that this neuroflexibility was characterized by initially decreased activation of this circuit in response to stress, followed by its increased activation with sustained stress exposure. The authors noted that previous research has consistently shown that repeated and chronic stress damages the structure, connections, and functions of the brain’s prefrontal cortex. The prefrontal cortex is the seat of higher order functions such as language, social behavior, mood, and attention, and which also helps regulate emotions, and more primitive areas of the brain.
In the current study, the authors reported that participants who did not show the neuroflexibility response in the prefrontal cortex during stress had higher levels of self-reported binge drinking, anger outbursts, and other maladaptive coping behaviors. They hypothesize that such individuals might be at increased risk for alcohol use disorder or emotional dysfunction problems, which are hallmarks of chronic exposure to high levels of stress.
FDA Approves First Intraocular Lens with Extended Range of Vision for Cataract Patients
Cataracts are a common eye condition where the natural lens becomes clouded, impairing a patient’s vision. According to the National Eye Institute, more than 20% of Americans will have cataracts by the age of 65, and the prevalence increases with age. In cataract surgery, the clouded natural lens is removed and replaced with an intraocular lens (IOL).
The FDA has approved the first IOL that provides cataract patients with an extended depth-of-focus, which helps improve their sharpness of vision (visual acuity) at near, intermediate and far distances. Traditional monofocal IOLs have been limited to improving distance vision. The Tecnis Symfony IOL improves visual acuity at close, intermediate and far ranges and, therefore, may reduce the need for patients to wear contact lenses or glasses after cataract surgery.
The approval is based on a review of results from a randomized clinical trial comparing 148 cataract patients implanted with the Tecnis Symfony IOL to 151 cataract patients implanted with a monofocal IOL. The study evaluated visual acuity at near, intermediate and far ranges; contrast sensitivity (the ability to distinguish small differences between light and dark); and adverse events for six months after implantation. Of the patients implanted with the Tecnis Symfony IOL, 77% had good vision (20/25), without glasses at intermediate distances, compared to 34% of those with the monofocal IOL. For near distances, patients with the Tecnis Symfony IOL were able to read two additional, progressively smaller lines on a standard eye chart than those with the monofocal IOL. Both sets of patients had comparable results for good distance vision.
Patients implanted with the Tecnis Symfony IOL may experience worsening of or blurred vision, bleeding or infection. The device may also cause reduced contrast sensitivity that becomes worse under poor visibility conditions such as dim light or fog. Some patients may experience visual halos, glare or starbursts. The device is not intended for use on patients who have had previous trauma to their eye.
The Tecnis Symfony Extended Range of Vision IOL, manufactured by Abbott Medical Optics, Inc. of Santa Ana, California, and is also available in four toric models, which are indicated for the reduction of residual refractive astigmatism or imperfections in the curvature of the eye.