|
Team finds bovine kobuvirus in US
University of Illinois at Urbana-Champaign, News Bureau Share Print E-Mail IMAGE IMAGE: University of Illinois veterinary clinical medicine professor Dr. Leyi Wang led the team that detected bovine kobuvirus in the U.S. view more Credit: Photo by L. Brian Stauffer CHAMPAIGN, Ill. -- A virus that afflicts cattle that was first discovered in Japan in 2003 has made its way to the U.S., researchers report in the journal Emerging Infectious Diseases. Bovine kobuvirus is fairly new to science, so its ill effects are not fully understood. It belongs to a family of viruses known as Picornaviridae, which includes Rhinovirus, a source of head colds and sinus infections in humans; and Poliovirus, which causes polio. Previous studies conducted elsewhere in the world have found bovine kobuvirus in fecal samples of cattle with diarrhea. The new study confirmed this association by sequencing the microbial DNA in samples from cattle in the U.S. and analyzing the intestines of two calves that died after infection. "Only bovine kobuvirus was detected in both cases," said University of Illinois veterinary clinical medicine professor Dr. Leyi Wang, who led the new study. "This provides evidence that this virus is the causative agent for calf diarrhea." So far, no other negative associations with bovine infection have been observed. However, since almost no one in North America is looking for the virus in cattle or other species, it remains to be seen how this emerging disease agent influences health, Wang said. "Continued surveillance of bovine kobuvirus is urgently needed to determine how widespread it is," Wang said. "Scientists have access to only a few genetic sequences of this virus in public databases. We need to be sequencing these viruses to learn more about their genetic diversity and evolution." Four of nine samples tested at the U. of I. Veterinary Diagnostic Laboratory were found to harbor bovine kobuvirus, the team reported. All of the infected cows were from the state of Illinois. Elsewhere in the world, bovine kobuvirus has been detected in about 10 countries in Asia, Europe, South America and Africa. |
Salmonella the most common cause of foodborne outbreaks in the European Union
Nearly one in three foodborne outbreaks in the EU in 2018 were caused by Salmonella, say the European Centre for Disease Prevention and Control and the European Food Safety Authority (EFSA) European Centre for Disease Prevention and Control (ECDC) Share Print E-Mail Nearly one in three foodborne outbreaks in the EU in 2018 were caused by Salmonella. This is one of the main findings of the annual report on trends and sources of zoonoses published today by the European Food Safety Authority (EFSA) and the European Centre for Disease Prevention and Control (ECDC). In 2018, EU Member States reported 5 146 foodborne outbreaks affecting 48 365 people. A foodborne disease outbreak is an incident during which at least two people contract the same illness from the same contaminated food or drink. Slovakia, Spain and Poland accounted for 67% of the 1581 Salmonella outbreaks. These outbreaks were mainly linked to eggs. "Findings from our latest Eurobarometer show that less than one third of European citizens rank food poisoning from bacteria among their top five concerns when it comes to food safety. The number of reported outbreaks suggests that there's room for raising awareness among consumers as many foodborne illnesses are preventable by improving hygiene measures when handling and preparing food" said EFSA's chief scientist Marta Hugas. Salmonellosis was the second most commonly reported gastrointestinal infection in humans in the EU (91 857 cases reported), after campylobacteriosis (246,571). West Nile virus and STEC infections at unusually high levels By far the highest increase in the zoonoses covered by this report was in the number of West Nile virus infections. Cases of this zoonotic mosquito-borne disease were seven times higher than in 2017 (1605 versus 212) and exceeded all cases reported between 2011 and 2017. "The reasons for the peak in 2018 are not fully understood yet. Factors like temperature, humidity or rainfall have been shown to influence seasonal activity of mosquitoes and may have played a role. While we cannot predict how intense the next transmission seasons will be, we know that the West Nile virus is actively circulating in many countries in the EU, affecting humans, horses and birds. ECDC is stepping up its support to countries in the areas of surveillance, preparedness, communication and vector control", said ECDC's chief scientist Mike Catchpole. Most locally acquired West Nile virus infections were reported by Italy (610), Greece (315) and Romania (277). Czechia and Slovenia reported their first cases since 2013. Italy and Hungary have also registered an increasing number of West Nile virus outbreaks in horses and other equine species in recent years. Shiga toxin-producing E. coli (STEC) has become the third most common cause of foodborne zoonotic disease with 8 161 reported cases - replacing yersiniosis with a 37% increase compared to 2017. This may be partly explained by the growing use of new laboratory technologies, making the detection of sporadic cases easier. The number of people affected by listeriosis in 2018 is similar to 2017 (2 549 in 2018 against 2 480 the previous year). However, the trend has been upward over the past ten years. Of the zoonotic diseases covered by the report, listeriosis accounts for the highest proportion of hospitalised cases (97%) and highest number of deaths (229), making it one of the most serious foodborne diseases. |
Paving the way to healing complex trauma
La Trobe University Share Print E-Mail A major study led by researchers at La Trobe University in Australia has identified key themes that will be used to inform strategies to support Australian Aboriginal and Torres Strait Islander parents in the first years of their children's lives. The Healing the Past by Nurturing the Future project aims to break the cycle of intergenerational and complex trauma experienced by Aboriginal and Torres Strait islander people, by co-designing strategies for new parents. The international research team, led by Associate Professor Catherine Chamberlain of La Trobe's Judith Lumley Centre and published today in the journal PLOS ONE, reviewed more than 20,000 scholarly articles to build a comprehensive understanding of pregnancy and birth for parents who have experienced trauma in their own childhood. The study identified seven themes, derived from studying interviews with more than 350 parents who experienced trauma as children, relate to parents' experiences during pregnancy, birth and the first few weeks after birth. Associate Professor Catherine Chamberlain said the research is critical for informing discussions with Aboriginal parents and communities to create a strong foundation for work to heal complex trauma. "This gives us a thorough and deep understanding needed to help co-design support strategies with communities to improve the lives of Aboriginal and Torres Strait Islander people and their babies," Associate Professor Chamberlain said. "We have shared these themes in discussions with Aboriginal and Torres Strait Islander parents and community members to see if any are relevant. Doing so also helps parents to understand these experiences are shared, even in other countries. "The next stage of our Healing the Past by Nurturing the Future project will use these themes to examine what support strategies have been evaluated in research. We will look at whether this research reflects what support parents say they want and what they feel works." The seven themes are: • New beginnings: Becoming a parent is an opportunity for 'a fresh start', to put the past behind them and move forward with hope for the future to create a new life for themselves and their child. • Changing roles and identities: Becoming a parent is a major life transition, influenced by perceptions of the parenting role. • Feeling connected: The quality of relationships with self, baby and others has major impacts on the experiences of becoming a parent. • Compassionate care: Kindness, empathy and sensitivity enables parents to build trust and feel valued and cared for. • Empowerment: Control, choice and 'having a voice' are critical to fostering safety. • Creating safety: Parents perceive the 'world as unsafe' and use conscious strategies to build safe places and relationships to protect themselves and their baby. • 'Reweaving' a future: Managing distress and healing while becoming a parent is a personal ongoing and complex process requiring strength, hope and support. Associate Professor Chamberlain said the seven themes also resonated strongly with Aboriginal and Torres Strait Islander parents and she was grateful to the research team for all their hard work and expertise, and to Lowitja Institute and the NHMRC for funding this phase of her work. |
News Release 13-Dec-2019
Breast-conserving treatment without surgery not supported at this time Results of NRG Oncology study BR005 NRG Oncology Share Print E-Mail SAN ANTONIO, TX - Results from NRG Oncology's BR005 study show that breast-conserving treatment without surgery cannot be recommended, based on the study criteria of clinical complete response, radiological complete response (rCR)/near rCR, and negative tumor bed biopsies. These findings were presented at the 2019 San Antonio Breast Cancer Symposium, held December 10-14. This phase II study, which opened in June 2017, was designed as a two-stage trial to assess the accuracy of tumor bed biopsies in predicting pathologic response in patients with clinical complete and radiological complete/near complete response after neoadjuvant chemotherapy to determine if they could avoid surgery. All patients had received chemotherapy for their breast cancer, but had not yet had surgery. All underwent an image-guided biopsy after receiving chemotherapy. A total of 105 patients were enrolled from August 2017 through June 2019, with 98 being evaluable for analysis. Accrual was temporarily closed for futility analysis on June 26, 2019, because 36 of the evaluable patients had residual disease at surgery, which actually met the numbers for the primary analysis. The negative predictive value of the biopsy was 77.5% (95%CI: 66.8% to 86.1%) which did not meet the pre-specified threshold of >90% required to support the feasibility of initiating a study in which surgery could be omitted. "Further analysis including central review of tri-modality imaging and assessment of an imaging algorithm with and without the addition of biopsy are underway. Once these are combined with information on biologic subtypes, a new prediction model will be defined," according to Mark Basik, MD, from Jewish General Hospital, and lead investigator of the study. ### NRG Oncology BR005 was supported by grants U10CA180868 (NRG Oncology Operations), and U10CA180822 (NRG Oncology SDMC). Clinicaltrials.gov identifier: NCT03188393. Citation Basik M, Cecchini RS, De Los Santos JF, Umphrey HR, Julian TB, Mamounas EP, White J, Lucas PC, Balanoff C, Tan AR, Weber JJ, Edmonson DA, Brown-Glaberman UA, Diego EJ, Teshome M, Matsen CB, Seaward SA, Wapnir IL, Wagner JL, Tjoe JA, Thompson AM, Wolmark N. Primary analysis of NRG-BR005, a phase II trial assessing accuracy of tumor bed biopsies in predicting pathologic complete response in patients with clinical/radiological complete response after neoadjuvant chemotherapy to explore the feasibility of breast-conserving treatment without surgery. San Antonio Breast Cancer Symposium 2019. Prog #: GS5-05. About NRG Oncology NRG Oncology conducts practice-changing, multi-institutional clinical and translational research to improve the lives of patients with cancer. Founded in 2012, NRG Oncology is a Pennsylvania-based nonprofit corporation that integrates the research of the legacy National Surgical Adjuvant Breast and Bowel Project (NSABP), Radiation Therapy Oncology Group (RTOG), and Gynecologic Oncology Group (GOG) programs. The research network seeks to carry out clinical trials with emphases on gender-specific malignancies, including gynecologic, breast, and prostate cancers, and on localized or locally advanced cancers of all types. NRG Oncology's extensive research organization comprises multidisciplinary investigators, including medical oncologists, radiation oncologists, surgeons, physicists, pathologists, and statisticians, and encompasses more than 1,300 research sites located world-wide with predominance in the United States and Canada. NRG Oncology is supported primarily through grants from the National Cancer Institute (NCI) and is one of five research groups in the NCI's National Clinical Trials Network. http://www.nrgoncology.org |
News Release 13-Dec-2019
Taking shape: Scientists propose new structure for shell of HIV-1 virus A newly proposed model for the shape of the HIV-1 viral shell may change how we understand the disease University of Alberta Share Print E-Mail IMAGE IMAGE: A new study proposes a new structure for the shell of the HIV-1 virus, pictured here. Image credit Marcelo Marcet. view more Credit: Marcelo Marcet The matrix shell of the HIV-1 virus may have a different shape than previously thought, and a newly proposed model has significant implications for understanding how the virus functions, according to a new study by University of Alberta scientists. The research suggests that the HIV-1 virus is housed within a spherical matrix shell. When it infects a healthy cell, the shell fuses to the outside of the target cell and then releases the viral capsid inside where it attacks the cell. "Our new proposed structure for the HIV-1 virus has a very peculiar shape, almost like petals of a flower," said Sean Graves, instructor in the Department of Mathematical and Statistical Sciences and co-author on the study. "A better structural knowledge of the matrix shell may help us understand the fusing and infection process." Graves is also coordinator of the Decima Robinson Support Centre, providing support to more than 1000 undergraduate students each term. The research shows that the previous model used to describe the structure of the HIV-1 matrix shell was mathematically impossible and provides a viable alternative. While it is too early to anticipate whether the model will translate into new treatment for HIV, the research will help scientists to better understand and make predictions about the behaviour of the HIV-1 virus. Around the world, nearly 38 million people suffer from HIV or AIDS. "Our contribution uses mathematical principles to help guide the scientific community in the right direction," added Marcelo Marcet-Palacios, adjunct professor of medicine in the Faculty of Medicine & Dentistry and co-author. "If our model is correct, then we can begin investigating ways we could block or interrupt the mechanism of viral entry. For example, by using a medication that could cross-link the 'petals' of the structure together to prevent the opening of the particle and thus stopping entry of the viral genome into the host cell." The model is available to anyone, anywhere in the world online. This research is the result of the work of an interdisciplinary team from the fields of biology, mathematics and computing science. One such collaborator is Weijie Sun, Faculty of Science alumnus and a former student of Graves'. "This collaboration made it possible to come up with a new model consistent with previously observed evidence and allowed us to develop a computer program freely accessible online that other scientists around the world can use to recreate our work and further develop this new model," said Sun. "It is incredible what can be achieved in science when experts from different disciplines get together and collaborate." ### |
News Release 12-Dec-2019
Ultrasound blasts potent glioblastoma drug into brain tumor Treatment successfully delivers drug across the blood-brain barrier directly to brain tumor in mice Northwestern University Share Print E-Mail • Glioblastoma currently has no cure. New treatments urgently needed • Powerful drug is 1,400 times more potent than current treatment against the brain tumor • Scientists applying to FDA for approval to test this novel treatment in patients with recurrent glioblastoma CHICAGO --- One of most potent drugs for treatment of glioblastoma, the most deadly type of brain tumor, can't be used in patients because of two problems. First, it can't reach its target because it's blocked by the blood-brain barrier, a microscopic structure that protects the brain from toxins in the blood. And the conventional formulation for this drug is toxic to the brain. But now Northwestern Medicine scientists have used a novel technology for opening the blood-brain barrier with an implantable ultrasound, and have delivered the powerful drug to the tumor in mice. In a new paper, they report on their findings of extensive preclinical research. The scientists also discovered brain toxicity for the conventional formulation for this drug - paclitaxel -to the brain was caused by the solution required to dissolve the drug (cremophor.) Scientists tested a new formulation of the drug that uses albumin as opposed to cremophor, and it was not harmful to the brain. Opening of the blood-brain barrier with an ultrasound increased the concentrations of this paclitaxel in the brain by five-fold. The study also showed that the brain tumor-bearing mice live much longer when treated with the powerful cancer-fighting drug paclitaxel, and survival was even further extended when treated in combination with ultrasound to open the blood-brain barrier. The study will be published Dec. 12 in Clinical Cancer Research, a journal of the American Association for Cancer Research. In the laboratory, paclitaxel is much more potent than the currently used chemotherapy temozolomide. When paclitaxel was tested against the brain tumor in a dish outside an organism, a 1,400-fold lesser drug concentration was necessary to kill same number of tumor cells, compared to the conventional chemotherapy used for this cancer. The scientists are now applying to the U.S. Food & Drug Administration to launch a clinical trial to test this concept of a new formulation of paclitaxel in combination with the novel ultrasound technology to open the blood-brain barrier in patients. The planned trial aims to determine if the treatment is safe, and if it prolongs survival of patients with brain cancer. "Glioblastoma currently has no cure, and when the tumor recurs there are not many treatment options," said the principal investigator for this study, Dr. Adam Sonabend, an assistant professor of neurological surgery at Northwestern University Feinberg School of Medicine and a Northwestern Medicine physician. "We urgently need effective new treatments." The ultrasound technology may have broader benefits. "This ultrasound technology now will enable us to use many agents established in other cancers for patients with brain tumors," said co-investigator Roger Stupp, chief of neuro-oncology and the Paul C. Bucy Professor of Neurological Surgery at Feinberg. Other clinical trials are testing ultrasound-based opening of the blood brain barrier with various chemotherapy agents, but none are using such a potent drug as paclitaxel. How does it work? The tiny ultrasound would be implanted during surgery into a window in the skull that does not contain bone. It is used in combination with microscopic gas bubbles injected into the blood at the same time the ultrasound begins. When the bubbles hit the sound waves, these vibrate and mechanically disrupt the blood-brain barrier. The opening is immediate, allowing penetration of the drug molecules. The blood-brain barrier opening is reversible and lasts for several hours after the sonication. The ultrasound emitter remains in the skull for repeated delivery of the drug. |
News Release 12-Dec-2019
The mathematics of prey detection in spider orb-webs Society for Industrial and Applied Mathematics Share Print E-Mail Spider webs are one of nature's most fascinating manifestations. Many spiders extrude proteinaceous silk to weave sticky webs that ensnare unsuspecting prey who venture into their threads. Despite their elasticity, these webs possess incredible tensile strength. In recent years, scientists have expressed increased interest in the spider orb-web as a biological-mechanical system. The web's sensory mechanisms are especially fascinating, given that most web-weaving spiders--regardless of their vision level--use generated vibrations to effectively locate ensnared prey. "The spider orb-web is a natural, lightweight, elegant structure with an extreme strength-to-weight ratio that is rarely observed among other structures, either natural or manmade," Antonino Morassi said. "Its primary functions are catching prey and gathering sensory information, and study of the mechanisms that guide these processes through web vibration has been one of the main research goals in the field." To understand the mechanics of orb-webs, researchers have previously utilized simplified patterns of wave propagation or relied upon numerical models that reproduce a spider web's exact geometry via one-dimensional elements. While these numerical models adequately handle wind, prey movement, and other sources of vibration, they fall short of providing insight into the physical phenomena responsible for web dynamics. In an article publishing this week in the SIAM Journal on Applied Mathematics, Morassi and Alexandre Kawano present a theoretical mechanical model to study the inverse problem of source identification and localize a prey in a spider orb-web. Due to structural interconnectivity between the circumferential and radial threads, vibrations in an orb-web spread laterally and move beyond the stimulated radius. This observation led Kawano and Morassi towards realistic mechanical models that measure a fibred web's two-dimensionality, rather than more limiting one-dimensional models. "There was no mechanical model--even a simplified one--that described the web as it really is: a two-dimensional vibrating system," Morassi said. "We decided to use a continuous membrane model since theoretical models often permit a deeper insight in the physical phenomena through analysis of the underlying mathematical structure of the governing equations." These equations are also useful in identifying the most relevant parameters that dictate a web's response. The authors classify their model as a network of two intersecting groups of circumferential and radial threads that form an uninterrupted, continuous elastic membrane with a specific fibrous structure. To set up the inverse problem, they consider the spider's dynamic response to the prey's induced vibrations from the center of the web (where the spider usually waits). For the sake of simplicity, Kawano and Morassi limit the model's breadth to circular webs. The geometry of their model allows for a specific fibrous structure, the radial threads of which are denser towards the web's center. The researchers note that the minimal data set to ensure uniqueness in the prey's localization seems to accurately reproduce real data that the spider collects right after the prey makes contact with the web. "By continuously testing the web, the spider acquires the dynamical response of the web approximately on a circle centered at the web's origin, and with radius significantly small with respect to the web dimensions," Kawano said. "Numerical simulations show that identification of the prey's position is rather good, even when the observation is taken on the discrete set of points corresponding to the eight legs of the spider." Ultimately, the authors hope that their novel mechanical model will encourage future research pertaining to nearly periodic signals and more general sources of vibration. They are already thinking about ways to further expand their model. "We believe that it may be of interest to generalize the approach to more realistic geometries -- for example, for spider webs that deviate a little from the circular axisymmetric shape and maintain only a single axis of symmetry," Morassi said. "Furthermore, here we considered the transversal dynamic response caused by orthogonal impact of a prey on the web. In real-world situations, impact can be inclined and cause in-plane vibrations to propagate throughout the web. The analysis of these aspects, among others, may provide novel and important insights, not only for the prey's catching problem but also for bioinspired fibrous networks for sensing applications involving smart multifunctional materials." |
News Release 11-Dec-2019
Virtual reality and drones help to predict and protect koala habitat Queensland University of Technology Share Print E-Mail Volume 90% VIDEO: QUT researchers have used a combination of virtual reality (VR), aerial thermal-imaging and ground surveys to build a better statistical model for predicting the location of koalas and, ultimately, protecting... view more Credit: QUT QUT researchers have used a combination of virtual reality (VR), aerial thermal-imaging and ground surveys to build a better statistical model for predicting the location of koalas and, ultimately, protecting their habitat. In the study, published in the journal PLoS ONE, researchers from QUT and the ARC Centre of Excellence for Mathematical and Statistical Frontiers (ACEMS) used the mashup of high-tech 360-degree imagery and heat-seeking drone cameras along with traditional techniques of ground surveys to develop a model that could be used to identify areas most likely to be home to koalas, which are facing population decline. Lead author Dr Catherine Leigh, who is also an Associate Investigator with ACEMS, said the advantage of the multi-pronged approach was that it greatly increased the accuracy of the statistical model. "It's about building a model that tells us with confidence where koalas are and where they're not," Dr Leigh said. "When you start building up a model with all of that data, you get a much better idea about where the koalas are likely to be. "If you can predict where koalas are, and the types of habitats they are hanging around in, then you know not only where to go to keep monitoring them but also the areas you need to protect." In the study, the researchers used ground survey information captured between 2102 and 2017 from Alexander Clarke Park in Loganholme, south-east Queensland, which is an area that has vegetation ranging from dense forest to grass fields and contains facilities including playgrounds and a dog park. Dr Leigh said one of the challenges with ground survey observations was that they could show a statistical bias of higher koala populations close to paths and other areas easily accessible by observers. "When you're out in the field as an experienced koala observer or a citizen scientist, you really are restricted where you can walk. And koalas are hard to see, even by trained observers," Dr Leigh said. "They are slow moving and often hidden high in the canopy." To counteract that, the researchers surveyed the area from the air using thermal cameras near sunrise, when the body heat of the koalas is detectable against the surrounding foliage. The third part of the study involved sending researchers out to some of the 82 specific locations in the area where koalas were known to either be or not be, to take 360-degree images. Those images were then shown to a panel of koala experts wearing VR headsets, with the experts asked to state how likely the environment they were viewing in was 'good koala habitat'. Dr Leigh said the advantage of using VR for the survey was it enabled them to bring the environment to the experts rather than having to take the experts to the field. "They're called immersive experiences," Dr Leigh said. "A lot of the research done on immersive experiences suggests that it helps to bring back the memories associated with when that expert has been in the field in the past, so they can be more cognizant of making the decision about the likelihood that a koala would be there." The researchers found that the three-pronged system of VR-prompted expert information, thermal imagery and ground surveys proved to be 75 per cent more accurate at predicting koala locations than ground surveys alone. "You put all three together and you get a much better model," Dr Leigh said. Dr Leigh said the methods could be used by councils and town planning authorities to obtain critical information needed for koala protection. |
Volume 90%
VIDEO: QUT researchers have used a combination of virtual reality (VR), aerial thermal-imaging and ground surveys to build a better statistical model for predicting the location of koalas and, ultimately, protecting... view more Credit: QUT QUT researchers have used a combination of virtual reality (VR), aerial thermal-imaging and ground surveys to build a better statistical model for predicting the location of koalas and, ultimately, protecting their habitat. In the study, published in the journal PLoS ONE, researchers from QUT and the ARC Centre of Excellence for Mathematical and Statistical Frontiers (ACEMS) used the mashup of high-tech 360-degree imagery and heat-seeking drone cameras along with traditional techniques of ground surveys to develop a model that could be used to identify areas most likely to be home to koalas, which are facing population decline. Lead author Dr Catherine Leigh, who is also an Associate Investigator with ACEMS, said the advantage of the multi-pronged approach was that it greatly increased the accuracy of the statistical model. "It's about building a model that tells us with confidence where koalas are and where they're not," Dr Leigh said. "When you start building up a model with all of that data, you get a much better idea about where the koalas are likely to be. "If you can predict where koalas are, and the types of habitats they are hanging around in, then you know not only where to go to keep monitoring them but also the areas you need to protect." In the study, the researchers used ground survey information captured between 2102 and 2017 from Alexander Clarke Park in Loganholme, south-east Queensland, which is an area that has vegetation ranging from dense forest to grass fields and contains facilities including playgrounds and a dog park. Dr Leigh said one of the challenges with ground survey observations was that they could show a statistical bias of higher koala populations close to paths and other areas easily accessible by observers. "When you're out in the field as an experienced koala observer or a citizen scientist, you really are restricted where you can walk. And koalas are hard to see, even by trained observers," Dr Leigh said. "They are slow moving and often hidden high in the canopy." To counteract that, the researchers surveyed the area from the air using thermal cameras near sunrise, when the body heat of the koalas is detectable against the surrounding foliage. The third part of the study involved sending researchers out to some of the 82 specific locations in the area where koalas were known to either be or not be, to take 360-degree images. Those images were then shown to a panel of koala experts wearing VR headsets, with the experts asked to state how likely the environment they were viewing in was 'good koala habitat'. Dr Leigh said the advantage of using VR for the survey was it enabled them to bring the environment to the experts rather than having to take the experts to the field. "They're called immersive experiences," Dr Leigh said. "A lot of the research done on immersive experiences suggests that it helps to bring back the memories associated with when that expert has been in the field in the past, so they can be more cognizant of making the decision about the likelihood that a koala would be there." The researchers found that the three-pronged system of VR-prompted expert information, thermal imagery and ground surveys proved to be 75 per cent more accurate at predicting koala locations than ground surveys alone. "You put all three together and you get a much better model," Dr Leigh said. Dr Leigh said the methods could be used by councils and town planning authorities to obtain critical information needed for koala protection. |
News Release 13-Dec-2019
How a protein in your brain could protect against Alzheimer's disease New research sets the stage for new therapeutic strategies for Alzheimer's disease University of Alberta Share Print E-Mail Research shows that white blood cells in the human brain are regulated by a protein called CD33--a finding with important implications in the fight against Alzheimer's disease, according to a new study by University of Alberta chemists. "Immune cells in the brain, called microglia, play a critical role in Alzheimer's disease," explained Matthew Macauley, assistant professor in theDepartment of Chemistry and co-author on the paper. "They can be harmful or protective. Swaying microglia from a harmful to protective state could be the key to treating the disease." Scientists have identified the CD33 protein as a factor that may decrease a person's likelihood of Alzheimer's disease. Less than 10 percent of the population have a version of CD33 that makes them less likely to get Alzheimer's disease. "The fact that CD33 is found on microglia suggests that immune cells can protect the brain from Alzheimer's disease under the right circumstances," said Abhishek Bhattacherjee, first author and postdoctoral fellow in the Macauley lab. Now, Macauley's research shows that the most common type of CD33 protein plays a crucial role in modulating the function of microglia. "These findings set the stage for future testing of a causal relationship between CD33 and Alzheimer's Disease, as well as testing therapeutic strategies to sway microglia from harmful to protecting against the disease--by targeting CD33," said Macauley. "Microglia have the potential to 'clean up' the neurodegenerative plaques, through a process called phagocytosis--so a therapy to harness this ability to slow down or reverse Alzheimer's disease can be envisioned." Macauley is an investigator with GlycoNet, a Canada-wide network of researchers based at the University of Alberta that is working to further our understanding of biological roles for sugars. GlycoNet provided key funding to get this project off the ground in the Macauley lab and continues to support the ongoing applications of the project. According to the Alzheimer's Association, 747,000 Canadians are currently living with Alzheimer's or another form of dementia. The disease affects more than 44 million people around the world. |
News Release 13-Dec-2019
Growing carbon nanotubes with the right twist Researchers synthetize nanotubes with a specific structure expanding previous theories on carbon nanotube growth Institute for Basic Science Share Print E-Mail IMAGE IMAGE: (a) Carbon nanotubes (CNTs) could be viewed as single-atom layer thick graphene sheets rolled into a cylinder. Different directions of rolling determine CNTs' properties. (b) Schematic diagram showing a carbon... view more Credit: IBS In a recently published paper in Science Advances, Feng Ding of the Center for Multidimensional Carbon Materials, within the Institute of Basic Science (IBS, South Korea) and colleagues, have achieved the creation of a specific type of carbon nanotubes (CNTs) with a selectivity of 90%, and expanded the current theory that explains the synthesis of these promising nano-cylinders. CNTs are incredibly strong and light nanomaterials made of carbon with superior current carrying capacity and very high thermal conductivity, making them ideal for electronic applications. Although CNTs are considered as some of the most interesting materials for the future, scientists are still struggling for their controllable synthesis. The CNTs' shape can be compared to paper tubes: in the same way as a cylinder can be created by rolling a sheet of paper, so CNTs can be imagined as a single layer of graphite rolled up on itself. Similarly, as different tubes can be produced by rolling a paper around its long side, its short side, or diagonally at different angles. Depending on the rolling direction, a graphite layer can produce different CNT structures, some are conducting and others are semiconducting, thus selectively creating a specific type of CNT will be key for their future use, such as building energy efficient computer chips. However, CNTs are not produced by rolling, but are grown nanometer after nanometer, adding carbon at the rim of nano-cylinders, one atom at a time. Despite various studies during the last three decades, the understanding on CNT growth remains very limited and rational experimental design for the growth of specific types of CNTs is challenging. One of the most promising manufacturing methods for CNT is the chemical vapor deposition (CVD). In this process, metal nanoparticles combined with carbon-containing gases form CNTs inside a high-temperature furnace. On the tip of the tubes, the metal nanoparticles play a critical role as catalysts: they dissociate the carbon source from the gases, and assist the attachment of these carbon atoms to the CNT wall, making the tubes longer and longer. The growth of the CNT terminates once the catalyst particle is encapsulated by graphitic or amorphous carbon. Carbon atoms are inserted onto the interface between a growing CNT and a catalyst nanoparticle, in active sites of the rim, and are available to incorporate new atoms. A previous model of CNT's growth rate showed that the latter is proportional to the density of these active sites at the interface between CNT and the catalyst, or the specific structure of the CNT. In this study, the researchers monitored the steady growth of CNTs on a magnesium oxide (MgO) support with carbon monoxide (CO) as the carbon feedstock and cobalt nanoparticles as catalysts at 700oC. The direct experimental measurements of 16 CNTs showed how to expand the previous theory. "It was surprising that the growth rate of a carbon nanotubes only depends on the size of the catalyst particle. This implies that our previous understanding on carbon nanotubes growth was not complete," says Maoshuai He, the first author of the paper. More specifically, carbon atoms that are deposited on the catalyst particle surface can be either incorporated on the active side of the CNT or removed by etching agents, such as H2, H2O, O2, or CO2. To explain the new experimental observations, the team included the effects of carbon insertion and removal during CNT growth and discovered that the growth rate depends on the catalyst's surface area and tube diameter ratio. "Compared to the previous model, we added three more factors: the rate of precursor deposition, the rate of carbon removal by etching agents, and the rate of carbon insertion into a carbon nanotube wall. When feedstock dissociation cannot be balanced by carbon etching, the rate of carbon nanotube growth will no longer depend on the structure of the carbon nanotube. On the other hand, the previous theory is still valid if the etching is dominating," explains Ding, a group leader of the Center for Multidimensional Carbon Materials. Interestingly, the new theory of CNT growth leads to a new mechanism to selectively grow a specific type of CNTs, denoted as (2n, n) CNTs, which is characterized by the maximum number of active sites at the interface between the CNT and the catalyst. This CNT structure would correspond to rolling a sheet of graphite diagonally at an angle of around 19 degrees. "If there is no carbon etching and the carbon nanotubes growth is slow, carbon atoms on the catalyst surface will accumulate," says Jin Zhang, co-author of the study and professor of Peking University, China. "This may lead to the formation of graphitic or amorphous carbon, which are established mechanisms of carbon nanotube growth termination. In this case, only carbon nanotubes which are able to add carbon atoms on their walls, that is with the highest number of active sites, can survive." Guided by the new theoretical understanding, the researchers were able to design experiments that produced (2n, n) CNTs with a selectivity of up to 90%: the highest selective growth of this type of CNT was achieved in the absence of any etching agent and with a high feedstock concentration. |
News Release 13-Dec-2019
Nanoscience breakthrough: Probing particles smaller than a billionth of a meter Tokyo Institute of Technology Share Print E-Mail IMAGE IMAGE: Tin oxide SNCs finely prepared by a dendrimer template method are loaded on the thin silica shell layers of plasmonic amplifiers, such that the Raman signals of the SNCs are... view more Credit: Science Advances Scientists at Tokyo Institute of Technology (Tokyo Tech) developed a new methodology that allows researchers to assess the chemical composition and structure of metallic particles with a diameter of only 0.5 to 2 nm. This breakthrough in analytical techniques will enable the development and application of minuscule materials in the fields of electronics, biomedicine, chemistry, and more. The study and development of novel materials have enabled countless technological breakthroughs and are essential across most fields of science, from medicine and bioengineering to cutting-edge electronics. The rational design and analysis of innovative materials at nanoscopic scales allows us to push through the limits of previous devices and methodologies to reach unprecedented levels of efficiency and new capabilities. Such is the case for metal nanoparticles, which are currently in the spotlight of modern research because of their myriad potential applications. A recently developed synthesis method using dendrimer molecules as a template allows researchers to create metallic nanocrystals with diameters of 0.5 to 2 nm (billionths of a meter). These incredibly small particles, called "subnano clusters" (SNCs), have very distinctive properties, such as being excellent catalyzers for (electro)chemical reactions and exhibiting peculiar quantum phenomena that are very sensitive to changes in the number of constituent atoms of the clusters. Unfortunately, the existing analytic methods for studying the structure of nanoscale materials and particles are not suitable for SNC detection. One such method, called Raman spectroscopy, consists of irradiating a sample with a laser and analyzing the resulting scattered spectra to obtain a molecular fingerprint or profile of the possible components of the material. Although traditional Raman spectroscopy and its variants have been invaluable tools for researchers, they still cannot be used for SNCs because of their low sensitivity. Therefore, a research team from Tokyo Tech, including Dr. Akiyoshi Kuzume, Prof. Kimihisa Yamamoto and colleagues, studied a way to enhance Raman spectroscopy measurements and make them competent for SNC analysis (Figure). One particular type of Raman spectroscopy approach is called surface-enhanced Raman spectroscopy. In its more refined variant, gold and/or silver nanoparticles enclosed in an inert thin silica shell are added to the sample to amplify optical signals and thus increase the sensitivity of the technique. The research team first focused on theoretically determining their optimal size and composition, where 100-nm silver optical amplifiers (almost twice the size commonly used) can greatly amplify the signals of the SNCs adhered to the porous silica shell. "This spectroscopic technique selectively generates Raman signals of substances that are in close proximity to the surface of the optical amplifiers," explains Prof. Yamamoto. To put these findings to test, they measured the Raman spectra of tin oxide SNCs to see if they could find an explanation in their structural or chemical composition for their inexplicably high catalytic activity in certain chemical reactions. By comparing their Raman measurements with structural simulations and theoretical analyses, they found new insights on the structure of the tin oxide SNCs, explaining the origin of atomicity-dependent specific catalytic activity of tin oxide SNCs. The methodology employed in this research could have great impact on the development of better analytic techniques and subnanoscale science. "Detailed understanding of the physical and chemical nature of substances facilitates the rational design of subnanomaterials for practical applications. Highly sensitive spectroscopic methods will accelerate material innovation and promote subnanoscience as an interdisciplinary research field," concludes Prof. Yamamoto. Breakthroughs such as the one presented by this research team will be essential for broadening the scope for the application of subnanomaterials in various fields including biosensors, electronics, and catalysts. |
News Release 13-Dec-2019
City College leads new photonics breakthrough City College of New York Share Print E-Mail IMAGE IMAGE: Light localized in space inside the topological crystal, entangled by interaction and topology. view more Credit: ITMO University A new approach to trapping light in artificial photonic materials by a City College of New York-led team could lead to a tremendous boost in the transfer speed of data online. Research into topological photonic metamaterials headed by City College physicist Alexander B. Khanikaev reveals that long-range interactions in the metamaterial changes the common behavior of light waves forcing them to localize in space. Further, the study shows that by controlling the degree of such interactions one can switch between trapped and extended (propagating) character of optical waves. "The new approach to trap light allows the design of new types of optical resonators, which may have a significant impact on devices used on a daily basis, said Khanikaev. "These range from antennas in smartphones and Wi-Fi routers, to optical chips in optoelectronics used for transferring data over the Internet with unprecedented speeds." Entitled "Higher-order topological states in photonic kagome crystals with long-range interactions," the research appears in the journal Nature Photonics published today. It is a collaboration between CCNY, the Photonics Initiative at the Graduate Center, CUNY; and ITMO University in St. Petersburg, Russia. As the lead organization, CCNY initiated the research and designed the structures, which were then tested both at CCNY and at ITMO University. Khanikaev's research partners included: Andrea Alù, Mengyao Li, Xiang Ni (CCNY/CUNY); Dmitry Zhirihin (CCNY/ ITMO); Maxim Gorlach, Alexey Slobozhanyuk (both ITMO), and Dmitry Filonov (Center for Photonics and 2D Materials, Moscow Institute of Physics and Technology. Research continues to extend the new approach to trap visible and infra-red light. This would further expand the range of possible applications of the discovery. |
News Release 13-Dec-2019
Colliding molecules and antiparticles A new theoretical study of the interaction between positrons and simple tetrahedral and octahedral molecules agrees with experimental work and could have useful implications for PET scanning techniques. Springer Share Print E-Mail Antiparticles - subatomic particles that have exactly opposite properties to those that make up everyday matter - may seem like a concept out of science fiction, but they are real, and the study of matter-antimatter interactions has important medical and technological applications. Marcos Barp and Felipe Arretche from the Universidade Federal de Santa Catarina, Brazil have modelled the interaction between simple molecules and antiparticles known as positrons and found that this model agreed well with experimental observations. This study has been published in EPJ D. Positrons, the antimatter equivalent of electrons, are the simplest and most abundant antiparticles, and they have been known and studied since the 1930s. Particle accelerators generate huge quantities of high-energy positrons, and most lab experiments require this energy to be reduced to a specific value. Typically, this is achieved by passing the positrons through a gas in an apparatus called a buffer-gas positron trap, so they lose energy by colliding with the molecules of the gas. However, we do not yet fully understand the mechanisms of energy loss at the atomic level, so it is difficult to predict the resulting energy loss precisely. Some of this energy is lost as rotational energy, when the positrons collide with gas molecules and cause them to spin. Barp and Arretche developed a model to predict this form of energy loss when positrons collide with molecules often used in buffer-gas positron traps: the tetrahedral carbon tetrafluoride (CF4) and methane (CH4), and the octahedral sulphur hexafluoride (SF6). They found that this model compared very well to experimental results. This model can be applied to collisions between positrons and any tetrahedral or octahedral molecules. Barp and Arretche hope that this improved understanding of how positrons interact with molecules will be used to improve techniques for positron emission tomography (PET) scanning in medicine, for example. |
News Release 13-Dec-2019
Better studying superconductivity in single-layer graphene An existing technique is better suited to describing superconductivity in pure, single-layer graphene than current methods Springer Share Print E-Mail Made up of 2D sheets of carbon atoms arranged in honeycomb lattices, graphene has been intensively studied in recent years. As well as the material's diverse structural properties, physicists have paid particular attention to the intriguing dynamics of the charge carriers its many variants can contain. The mathematical techniques used to study these physical processes have proved useful so far, but they have had limited success in explaining graphene's 'critical temperature' of superconductivity, below which its' electrical resistance drops to zero. In a new study published in EPJ B, Jacques Tempere and colleagues at the University of Antwerp in Belgium demonstrate that an existing technique is better suited for probing superconductivity in pure, single-layer graphene than previously thought. The team's insights could allow physicists to understand more about the widely varied properties of graphene; potentially aiding the development of new technologies. Typically, the approach they used in the study is used to calculate critical temperatures in conventional superconductors. In this case, however, it was more accurate than current techniques in explaining how critical temperatures are suppressed with lower densities of charge carriers, as seen in pure, single-layer graphene. In addition, it proved more effective in modelling the conditions which give rise to interacting pairs of electrons named 'Cooper pairs', which strongly influence the electrical properties of the material. Tempere's team made their calculations using the 'dielectric function method' (DFM), which accounts for the transfer of heat and mass within materials when calculating critical temperatures. Having demonstrated the advantages of the technique, they now suggest that it could prove useful for future studies aiming to boost and probe for superconductivity in single and bilayer graphene. As graphene research continues to be one of the most diverse, fast-paced fields in materials physics, the use of DFM could better equip researchers to utilise it for ever more advanced technological applications. |
News Release 13-Dec-2019
Research calls for new measures to treat mental illness and opioid use University of Waterloo Share Print E-Mail Opioid use among psychiatric hospital patients needs to be addressed through an integrated approach to managing mental illness, pain and substance use, a study by researchers at the University of Waterloo has found. The study found that 7.5 per cent of 165,434 patients admitted to psychiatric hospitals in Ontario between 2006 and 2017 had used opioids in the year prior to admission, which compares to estimates that 2 per cent of the general population used opioids in 2015. Among patients who said they experience daily pain, the percentage who reported opiate use jumped to 22 per cent. "The patterns of use we saw are problematic," said Christopher Perlman, a public health researcher. "Opiate use is strongly linked to pain, mental health conditions and use of other drugs. While we don't know how many patients were initially prescribed an opioid for pain, we do know that a large number of patients reporting pain in psychiatry also have an addiction concern." The study highlights the challenging circumstances faced by those who use opioids. For instance, opiate use was almost twice as common among those whose employment or education was at risk (10.5 per cent) compared to those not at risk (5.8 per cent). Many patients who had used opiates did not have a partner or spouse, and individuals living in rural and northern communities were more likely to use opiates, as were young people, and males rather than females. "If we are serious about supporting people with mental and physical health concerns, we need an integrated approach to service delivery, which includes assessing and addressing the risk of addiction," said Perlman, who is a professor in the School of Public Health and Health Systems at the University of Waterloo. "Right now, the way our health system is structured and funded, it's not easy to integrate physical, mental and substance use services." "This study was able to shed some light on the needs of persons who use opioids, but this is really the tip of the iceberg. Because we lack integrated health information systems across various health providers, we really don't know the extent of the physical and health needs of individuals who use opioids across the population. That means they are either getting help elsewhere, which would be good - or more likely, that they are not getting care they need." The paper, "Factors Associated With Opiate Use Among Psychiatric Inpatients: A Population-Based Study of Hospital Admissions in Ontario, Canada" was co-authored by Oluwakemi Aderibigbe (Waterloo), Anthony Renda (independent), and Christopher Perlman (Waterloo), and published in Health Services Insights. |
News Release 13-Dec-2019
Excessive antibiotic prescriptions for children in low-, middle-income countries Many of the prescriptions given from birth through age 5 are unnecessary and might exacerbate resistance Harvard T.H. Chan School of Public Health Share Print E-Mail Boston, MA - Children in low- and middle-income countries (LMICs) are receiving an average of 25 antibiotic prescriptions during their first five years of life, an excessive amount that could harm the children's ability to fight pathogens as well as increase antibiotic resistance worldwide, according to a new study from the Swiss Tropical and Public Health Institute (Swiss TPH) and Harvard T.H. Chan School of Public Health. "We knew children in LMICs are sick more often, and we knew antibiotic prescription rates are high in many countries. What we did not know was how these elements translate into actual antibiotic exposure--and the results are rather alarming," said Günther Fink, lead author of the study and head of the Household Economics and Health Systems Research unit at Swiss TPH. The study--the first to look at total antibiotic prescribing in children under the age of five in LMICs--will be published on 13 December in The Lancet Infectious Diseases. Global health threat Antimicrobial resistance is one of today's biggest threats to global health and development, according to the World Health Organization. One factor contributing to this global health threat is the excessive use of antibiotics worldwide. Previous studies have shown that antibiotics are overprescribed to children in many countries. In Tanzania, for instance, several studies have shown that over 90% of children who visit a health facility receive an antibiotic, although only in about 20% of the cases treatment was actually required. The research team from Swiss TPH and Harvard Chan School analyzed data from 2007-2017 from health facilities and household surveys from eight countries: Haiti, Kenya, Malawi, Namibia, Nepal, Senegal, Tanzania, and Uganda. The study found that, on average, children received 25 antibiotic prescriptions through age five--a "remarkable" estimate, the authors wrote, given that two antibiotic prescriptions per year is considered excessive in many high-income settings. Results showed that antibiotics were administered in 81% of cases for children with a respiratory illness, in 50% for children with diarrhea, and in 28% for children with malaria. The researchers found that the number of antibiotic prescriptions in early childhood varied from country to country: While a child in Senegal received approximately one antibiotic prescription per year in the first five years of life, a child in Uganda was prescribed up to 12. In comparison, a prior study showed that children under five in Europe receive less than one antibiotic prescription per year on average. "This number is still high given that the vast majority of infections in this age group are of viral origin," said Valérie D'Acremont, a study co-author and head of the Management of Fevers group at Swiss TPH. "What is unique about this study is that it provides a much more comprehensive picture of pediatric antibiotic exposure in LMICs than what has been reported previously. It combines both household data on where and when children are brought for care with data from direct observations of health care workers caring for sick children," said Jessica Cohen, the Bruce A. Beal, Robert L. Beal, and Alexander S. Beal Associate Professor of Global Health at Harvard Chan School and senior author of the study. Impact on children "The consequences of antibiotic overprescription not only pose a huge threat to global health, but can also result in a concrete health impact for these children," said Valérie D'Acremont. "Excess antibiotic use destroys the natural gut flora which is essential to fighting pathogens." A Swiss TPH research project is underway to better comprehend the health impact of overusing antibiotics on children. "Understanding the concrete impact on individual children is crucial to achieve a policy change," said Fink. His research team is currently comparing policies at a country level to identify best practices that lead to lower antibiotic prescription rates. |
13-Dec-2019
Mayo Clinic researchers present findings at the 2019 San Antonio Breast Cancer Symposium Mayo Clinic Share Print E-Mail SAN ANTONIO -- Mayo Clinic researchers will present findings at the San Antonio Breast Cancer Symposium Dec. 10-14 in San Antonio. New Mayo Clinic studies to be presented include: •"Women at Elevated Risk of Developing Breast Cancer May Benefit From Taking Anti-inflammatory Drugs" •Embargoed until Friday, Dec. 13, at 6 p.m. EST •Research from Mayo Clinic investigators suggest that some women with an elevated risk of developing breast cancer may benefit from taking anti-inflammatory medications. "Several studies have evaluated whether the use of anti-inflammatory medications such as aspirin, ibuprofen and naproxen affect a woman's risk of developing breast cancer," says Amy Degnim, M.D., a breast surgical oncologist at Mayo Clinic in Minnesota, "but little is known about how use of these drugs might affect their risk after a benign breast biopsy." Dr. Degnim says about one million women receive a diagnosis of benign breast disease annually in the U.S. and having this history increases their risk of developing breast cancer. Researchers surveyed women who had undergone a benign breast biopsy at Mayo Clinic between 1992 and 2001, and asked them to report which types of these medications they had used and for how long. Researchers also obtained information on which women had developed breast cancer at any point in the years after their initial benign biopsy. "We found that women who reported using ibuprofen or naproxen had an approximately 40% reduction in breast cancer risk, while women who reported using aspirin had no reduction in breast cancer risk," says Dr. Degnim. "Women who used the drugs more frequently on a regular basis also had greater protection from breast cancer." Dr. Degnim says the findings suggest that women who have had a benign breast biopsy may benefit from medications that reduce inflammation, except for aspirin, in terms of reducing later breast cancer risk. She cautions that this study was not a clinical trial and she does not recommend that all women should take these medications to reduce their breast cancer risk. "Our results support the need for a clinical trial to further investigate the risks and benefits of taking these medications to lower breast cancer risk." "Young Women With Breast Cancer May Help Preserve Fertility by Avoiding Intensive Chemotherapy" Embargoed until Thursday, Dec. 12, at 8 a.m. EST Young women with HER 2-positive breast cancer may help preserve their fertility by choosing one type of chemotherapy over another according to the findings of a study led by Kathryn Ruddy, M.D., an oncologist at Mayo Clinic. "Ovarian dysfunction is an important issue after cancer treatment because it can be associated with infertility and menopausal symptoms, such as hot flashes and impaired sexual function," says Dr. Ruddy. Dr. Ruddy and her team surveyed study participants taking part in a randomized clinical trial testing the efficacy of T-DM1 versus a combination of paclitaxel and trastuzumab. Participants were asked questions about menstrual periods. "We found that young women with HER 2-positive breast cancer may be more likely to resume menstruation after receipt of two relatively new treatments, T-DM1 or a combination of paclitaxel and trastuzumab, than we have seen previously in young women who received older, more intensive chemotherapy regimens." Dr. Ruddy says the findings should be good news for women who want to maintain fertility after treatment for breast cancer and that menopausal symptoms such as hot flashes may be less burdensome for patients treated with the newer regimens. Dr. Ruddy and her colleagues will perform additional analyses on the effect of tamoxifen on these results before publishing a paper on this study. "Researchers Develop Tool to Identify Patients at Higher Risk of Heart Damage From Breast Cancer Therapy" Embargoed until Friday, Dec. 13, at 6 p.m. EST Researchers at Mayo Clinic in Florida have developed a tool to help identify patients who may be at higher risk of developing heart damage from anti HER 2 breast cancer therapy at an early stage. "Cardiac toxicity is a known complication of anti-HER 2 therapy," says Pooja Advani, M.B.B.S., M.D., a Mayo Clinic oncologist. Dr. Advani says clinical studies have confirmed that the use of anti-HER 2 therapy in breast cancer patients can have a profound effect on patient survival. "The most common manifestation of cardiac toxicity in breast cancer patients receiving anti-HER 2 therapy is a reduction in the ejection fraction without any symptoms," says Dr. Advani. Ejection fraction is a measurement of the percentage of blood leaving the heart each time it contracts. Dr. Advani says risk factors, such as older age; a lower ejection fraction prior to the start of treatment; and the use of anthracycline chemotherapy, such as doxorubin or Adriamycin, have been consistently associated with a higher risk of cardiac toxicity from anti-HER 2 therapy. Dr. Advani and her colleagues followed 604 breast cancer patients who were treated with anti-HER 2 agents at Mayo Clinic. They collected patient data, including, age, race, gender, body mass index, smoking history, medical comorbidities, use of heart medications, baseline heart function, thickness of the heart muscle and prior use of anthracycline chemotherapy. Researchers identified patients who developed cardiac toxicity -- asymptomatic, symptomatic, or both. They performed a statistical analysis to identify risk factors that were associated with a high risk of developing cardiac dysfunction. "We found that patients with certain risk factors including being over the age of 55, having a lower baseline heart function (ejection fraction less than 60 percent), having received anthracycline chemotherapy or patients having enlargement and thickening of the heart walls were most significantly associated with an increased risk of developing cardiac toxicity," says Dr. Advani. "This is consistent with previously reported studies." Dr. Advani says patients receiving radiation therapy as a part of their breast cancer treatment were not found to be at a significantly higher risk of developing cardiac toxicity from anti-HER 2 therapy based on their findings. Dr. Advani and her colleagues created a risk prediction model by assigning a score to each factor mentioned above and found that the cumulative risk score was a highly significant predictor of cardiac toxicity in patients. "Using a risk prediction model at therapy initiation may help us identify patients who may benefit from an early referral to a cardiologist for close cardiac monitoring and treatment with medications to protect their heart function," says Dr. Advani. |
News Release 13-Dec-2019
Research calls for new measures to treat mental illness and opioid use University of Waterloo Share Print E-Mail Opioid use among psychiatric hospital patients needs to be addressed through an integrated approach to managing mental illness, pain and substance use, a study by researchers at the University of Waterloo has found. The study found that 7.5 per cent of 165,434 patients admitted to psychiatric hospitals in Ontario between 2006 and 2017 had used opioids in the year prior to admission, which compares to estimates that 2 per cent of the general population used opioids in 2015. Among patients who said they experience daily pain, the percentage who reported opiate use jumped to 22 per cent. "The patterns of use we saw are problematic," said Christopher Perlman, a public health researcher. "Opiate use is strongly linked to pain, mental health conditions and use of other drugs. While we don't know how many patients were initially prescribed an opioid for pain, we do know that a large number of patients reporting pain in psychiatry also have an addiction concern." The study highlights the challenging circumstances faced by those who use opioids. For instance, opiate use was almost twice as common among those whose employment or education was at risk (10.5 per cent) compared to those not at risk (5.8 per cent). Many patients who had used opiates did not have a partner or spouse, and individuals living in rural and northern communities were more likely to use opiates, as were young people, and males rather than females. "If we are serious about supporting people with mental and physical health concerns, we need an integrated approach to service delivery, which includes assessing and addressing the risk of addiction," said Perlman, who is a professor in the School of Public Health and Health Systems at the University of Waterloo. "Right now, the way our health system is structured and funded, it's not easy to integrate physical, mental and substance use services." "This study was able to shed some light on the needs of persons who use opioids, but this is really the tip of the iceberg. Because we lack integrated health information systems across various health providers, we really don't know the extent of the physical and health needs of individuals who use opioids across the population. That means they are either getting help elsewhere, which would be good - or more likely, that they are not getting care they need." The paper, "Factors Associated With Opiate Use Among Psychiatric Inpatients: A Population-Based Study of Hospital Admissions in Ontario, Canada" was co-authored by Oluwakemi Aderibigbe (Waterloo), Anthony Renda (independent), and Christopher Perlman (Waterloo), and published in Health Services Insights |
News Release 13-Dec-2019
New methods could help researchers watch neurons compute Stanford University Share Print E-Mail Since the 1950s at least, researchers have speculated that the brain is a kind of computer in which neurons make up complex circuits that perform untold numbers of calculations every second. Decades later, neuroscientists know that these brain circuits exist, yet technical limitations have kept most details of their computations out of reach. Now, neuroscientists reported December 12 in Cell, they may finally be able to reveal what circuits deep in the brain are up to, thanks in large part to a molecule that lights up brighter than ever before in response to subtle electrical changes that neurons use to perform their compuations. Currently, one of the best ways to track neurons' electrical activity is with molecules that light up in the presence of calcium ions, a proxy for a neuron spike, the moment when one neuron passes an electrical signal to another. But calcium flows too slowly to catch all the details of a neuron spike, and it doesn't respond at all to the subtle electrical changes that lead up to a spike. (One alternative is to implant electrodes, but those implants ultimately damage neurons, and it isn't practical to place electrodes in more than a handful of neurons at once in living animals.) To solve those problems, researchers led by Michael Lin, an associate professor of neurobiology and of bioengineering and a member of the Wu Tsai Neurosciences Institute, and Stéphane Dieudonné, an INSERM research director at the École Normale Supérieure in Paris, focused on fluorescent molecules whose brightness responds directly to voltage changes in neurons, an idea Lin and his team had been working on for years. Still, those molecules had a problem of their own: Their brightness hasn't always been that responsive to voltage, so Lin and his team at Stanford turned to a well-known method in biology called electroporation. In that technique, researchers use electrical probes to zap holes in cell membranes, with the side effect that their voltage drops rapidly to zero like a punctured battery. By zapping a library of candidate molecules, Lin and colleagues could then select those whose brightness was most responsive to the voltage shift. The resulting molecule, called ASAP3, is the most responsive voltage indicator to date, Lin said. Dieudonné and his lab focused on another problem: how to scan neurons deep in the brain more efficiently. To make fluorescent molecules such as ASAP3 light up deep in the brain, researchers often use a technique called two-photon imaging, which employs infrared laser beams that can penetrate through tissue. Then, in order to scan multiple neurons fast enough to see a spike, which itself lasts only about a thousandth of a second, researchers must move the laser spot quickly from neuron to neuron -- something hard to do reliably in moving animals. The solution, Dieudonné and colleagues found, was a new algorithm called ultrafast local volume excitation, or ULoVE, in which a laser rapidly scans several points in the volume around a neuron, all at once. "Such strategies, where each laser pulse is shaped and sent to the right volume within the tissue, constitute the optimal use of light power and will hopefully allow us to record and stimulate millions of locations in the brain each second," Dieudonné said. that illuminates multiple points at once. Putting those techniques together, the researchers showed in mice that they could track fine details of brain activity in much of the mouse cortex, the top layers of the brain that control movement, decision making and other higher cognitive functions. "You can now look at neurons in living mouse brains with very high accuracy, and you can track that for long periods of time," Lin said. Among other things, that opens the door to studying not only how neurons process signals from other neurons and how they decide, so to speak, when to spike, but also how neurons' calculations change over time. In the meantime, Lin and colleagues are focused on further improving on their methods. "ASAP3 is very usable now, but we're confident there will be an ASAP4 and ASAP5," he said. |
| All times are GMT. The time now is 05:20. |
VietBF - Vietnamese Best Forum Copyright ©2006 - 2024
User Alert System provided by
Advanced User Tagging (Pro) -
vBulletin Mods & Addons Copyright © 2024 DragonByte Technologies Ltd.