Common herbal supplement can cause dangerous interactions with prescription drugs

St. John’s wort, the leading complementary and alternative treatment for depression in the United States, can be dangerous when taken with many commonly prescribed drugs, according to a study by researchers at Wake Forest Baptist Medical Center.The researchers reported that the herbal supplement can reduce the concentration of numerous drugs in the body, including oral contraceptive, blood thinners, cancer chemotherapy and blood pressure medications, resulting in impaired effectiveness and treatment failure.”Patients may have a false sense of safety with so-called ‘natural’ treatments like St. John’s wort,” said Sarah Taylor, M.D., assistant professor of dermatology at Wake Forest Baptist and lead author of the study. “And it is crucial for physicians to know the dangers of ‘natural’ treatments and to communicate the risks to patients effectively.” The study is published in the current online issue of The Journal of Alternative and Complementary Medicine.To determine how often S. John’s wort (SJW) was being prescribed or taken with other medications, the team conducted a retrospective analysis of nationally representative data collected by the National Ambulatory Medical Care Survey from 1993 to 2010. The research team found the use of SJW in potentially harmful combinations in 28 percent of the cases reviewed.Possible drug interactions can include serotonin syndrome, a potentially fatal condition that causes high levels of the chemical serotonin to accumulate in your body, heart disease due to impaired efficacy of blood pressure medications or unplanned pregnancy due to contraceptive failure, Taylor said.Limitations of the study are that only medications recorded by the physician were analyzed. However, she said the rate of SJW interactions may actually be underestimated because the database did not include patients who were using SJW but did not tell their doctor.”Labeling requirements for helpful supplements such as St. John’s wort need to provide appropriate cautions and risk information,” Taylor said, adding that France has banned the use of St. John’s wort products and several other countries, including Japan, the United Kingdom, and Canada, are in the process of including drug-herb interaction warnings on St. John’s wort products.”Doctors also need to be trained to always ask if the patient is taking any supplements, vitamins, minerals or herbs, especially before prescribing any of the common drugs that might interact with St. …

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‘3-D’ test could reduce reliance on animals for testing asthma and allergy medications

To determine whether new medicines are safe and effective for humans, researchers must first test them in animals, which is costly and time-consuming, as well as ethically challenging. In a study published in ACS’ journal Molecular Pharmaceutics, scientists report that they’ve developed a simple, “3D” laboratory method to test asthma and allergy medications that mimics what happens in the body, which could help reduce the need for animal testing.Amir Ghaemmaghami and colleagues note that respiratory conditions, such as asthma and allergies, are becoming more common. These conditions affect the lungs and the airway leading to the lungs, making it difficult to breathe. Every year, respiratory symptoms lead to expensive hospital visits, as well as absences from work and school. Better drugs could provide relief, but before giving new medicines to people, researchers must first test them in animals — a costly and laborious process. Sometimes, researchers will use “2D” tests in which they apply the drug to a layer of human cells in a lab dish instead, but this isn’t an adequate way to tell how a medicine will work in a whole animal or a whole person. So, Ghaemmaghami’s team developed a new, 3D alternative.Their test includes three types of human cells that are typically in a person’s airway. In the body, these cells are close together and are involved in the development of respiratory conditions. The 3D “model” reacted just like a real person’s airway when they exposed it to allergens and bacterial extract. They say that the model has the potential of reducing the need for some animal testing of new drugs for respiratory conditions.Story Source:The above story is based on materials provided by American Chemical Society. …

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Natural plant compounds may assist chemotherapy

Researchers at Plant & Food Research have identified plant compounds present in carrots and parsley that may one day support more effective delivery of chemotherapy treatments.Scientists at Plant & Food Research, working together with researchers at The University of Auckland and the National Cancer Institute of The Netherlands, have discovered specific plant compounds able to inhibit transport mechanisms in the body that select what compounds are absorbed into the body, and eventually into cells. These same transport mechanisms are known to interfere with cancer chemotherapy treatment.The teams’ research, recently published in the European Journal of Pharmacology, showed that falcarinol type compounds such as those found in carrots and parsley may support the delivery of drug compounds which fight breast cancer by addressing the over-expression of Breast Cancer Resistance Protein (BCRP/ABCG2), a protein that leads to some malignant tissues ability to become resistant to chemotherapy.”It’s very exciting work,” says Plant & Food Research Senior Scientist, Dr Arjan Scheepens. “Our work is uncovering new means to alter how the body absorbs specific chemical and natural compounds. Ultimately we are interested in how food could be used to complement conventional treatments to potentially deliver better results for patients.”Story Source:The above story is based on materials provided by New Zealand Institute for Plant and Food Research. Note: Materials may be edited for content and length.

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MRI reveals genetic activity: Deciphering genes’ roles in learning and memory

Doctors commonly use magnetic resonance imaging (MRI) to diagnose tumors, damage from stroke, and many other medical conditions. Neuroscientists also rely on it as a research tool for identifying parts of the brain that carry out different cognitive functions.Now, a team of biological engineers at MIT is trying to adapt MRI to a much smaller scale, allowing researchers to visualize gene activity inside the brains of living animals. Tracking these genes with MRI would enable scientists to learn more about how the genes control processes such as forming memories and learning new skills, says Alan Jasanoff, an MIT associate professor of biological engineering and leader of the research team.”The dream of molecular imaging is to provide information about the biology of intact organisms, at the molecule level,” says Jasanoff, who is also an associate member of MIT’s McGovern Institute for Brain Research. “The goal is to not have to chop up the brain, but instead to actually see things that are happening inside.”To help reach that goal, Jasanoff and colleagues have developed a new way to image a “reporter gene” — an artificial gene that turns on or off to signal events in the body, much like an indicator light on a car’s dashboard. In the new study, the reporter gene encodes an enzyme that interacts with a magnetic contrast agent injected into the brain, making the agent visible with MRI. This approach, described in a recent issue of the journal Chemical Biology, allows researchers to determine when and where that reporter gene is turned on.An on/off switchMRI uses magnetic fields and radio waves that interact with protons in the body to produce detailed images of the body’s interior. In brain studies, neuroscientists commonly use functional MRI to measure blood flow, which reveals which parts of the brain are active during a particular task. When scanning other organs, doctors sometimes use magnetic “contrast agents” to boost the visibility of certain tissues.The new MIT approach includes a contrast agent called a manganese porphyrin and the new reporter gene, which codes for a genetically engineered enzyme that alters the electric charge on the contrast agent. Jasanoff and colleagues designed the contrast agent so that it is soluble in water and readily eliminated from the body, making it difficult to detect by MRI. However, when the engineered enzyme, known as SEAP, slices phosphate molecules from the manganese porphyrin, the contrast agent becomes insoluble and starts to accumulate in brain tissues, allowing it to be seen.The natural version of SEAP is found in the placenta, but not in other tissues. …

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Military dermatologists making strides in applying treatments for wounded warriors to injured civilians

For the millions of men and women serving in the U.S. military, injuries are a job hazard that can be nearly impossible to avoid in the line of duty. As a result, many in the military suffer from scars and wounds that, in some cases, last a lifetime and pose considerable challenges by restricting motion in affected limbs when performing common, everyday activities.To aid in the function and appearance of battlefield scars, military dermatologists began experimenting with ablative fractional laser surgery — known to improve the appearance of acne scars. Results over the last seven years have been impressive, and dermatologists now are treating civilians injured from car accidents, fires and job and household accidents with this laser therapy to enhance scar and wound healing.Information was provided by board-certified dermatologist Chad M. Hivnor, MD, LtCol, USAF, MC, FS, staff dermatologist (Chief Research, Chief Lasers) for the San Antonio Military Health System.Dr. Hivnor recently received the Paul W. Myers Award from the Air Force Association for his work using fractional lasers to treat scars and improve range of motion for wounded service members. The Paul W. Myers Award honors the Air Force medical corps officer who has made the largest contribution to the overall health and well-being of men and women in the branch.Physical and Cosmetic Aspects of Scars Improve With LaserAblative fractional lasers work by delivering very tiny columns of heat quickly to the top and deeper layers of skin, which produces a wound that heals with the help of the surrounding healthy skin tissue. When Dr. …

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Scientists find mechanism to reset body clock

Researchers from The University of Manchester have discovered a new mechanism that governs how body clocks react to changes in the environment.And the discovery, which is being published in Current Biology, could provide a solution for alleviating the detrimental effects of chronic shift work and jet-lag.The team’s findings reveal that the enzyme casein kinase 1epsilon (CK1epsilon) controls how easily the body’s clockwork can be adjusted or reset by environmental cues such as light and temperature.Internal biological timers (circadian clocks) are found in almost every species on the planet. In mammals including humans, circadian clocks are found in most cells and tissues of the body, and orchestrate daily rhythms in our physiology, including our sleep/wake patterns and metabolism.Dr David Bechtold, who led The University of Manchester’s research team, said: “At the heart of these clocks are a complex set of molecules whose interaction provides robust and precise 24 hour timing. Importantly, our clocks are kept in synchrony with the environment by being responsive to light and dark information.”This work, funded by the Biotechnology and Biological Sciences Research Council, was undertaken by a team from The University of Manchester in collaboration with scientists from Pfizer led by Dr Travis Wager.The research identifies a new mechanism through which our clocks respond to these light inputs. During the study, mice lacking CK1epsilon, a component of the clock, were able to shift to a new light-dark environment (much like the experience in shift work or long-haul air travel) much faster than normal.The research team went on to show that drugs that inhibit CK1epsilon were able to speed up shift responses of normal mice, and critically, that faster adaption to the new environment minimised metabolic disturbances caused by the time shift.Dr Bechtold said: “We already know that modern society poses many challenges to our health and wellbeing — things that are viewed as commonplace, such as shift-work, sleep deprivation, and jet lag disrupt our body’s clocks. It is now becoming clear that clock disruption is increasing the incidence and severity of diseases including obesity and diabetes.”We are not genetically pre-disposed to quickly adapt to shift-work or long-haul flights, and as so our bodies’ clocks are built to resist such rapid changes. Unfortunately, we must deal with these issues today, and there is very clear evidence that disruption of our body clocks has real and negative consequences for our health.”He continues: “As this work progresses in clinical terms, we may be able to enhance the clock’s ability to deal with shift work, and importantly understand how maladaptation of the clock contributes to diseases such as diabetes and chronic inflammation.”Story Source:The above story is based on materials provided by University of Manchester. Note: Materials may be edited for content and length.

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Older adults: Build muscle and you’ll live longer

New UCLA research suggests that the more muscle mass older Americans have, the less likely they are to die prematurely. The findings add to the growing evidence that overall body composition — and not the widely used body mass index, or BMI — is a better predictor of all-cause mortality.The study, published in the American Journal of Medicine, is the culmination of previous UCLA research led by Dr. Preethi Srikanthan, an assistant clinical professor in the endocrinology division at the David Geffen School of Medicine at UCLA, that found that building muscle mass is important in decreasing metabolic risk.”As there is no gold-standard measure of body composition, several studies have addressed this question using different measurement techniques and have obtained different results,” Srikanthan said. “So many studies on the mortality impact of obesity focus on BMI. Our study indicates that clinicians need to be focusing on ways to improve body composition, rather than on BMI alone, when counseling older adults on preventative health behaviors.”The researchers analyzed data collected by the National Health and Nutrition Examination Survey (NHANES) III, conducted between 1988 and 1994. They focused on a group of 3,659 individuals that included men who were 55 or older and women who were 65 or older at the time of the survey. The authors then determined how many of those individuals had died from natural causes based on a follow-up survey done in 2004.The body composition of the study subjects was measured using bioelectrical impedance, which involves running an electrical current through the body. Muscle allows the current to pass more easily than fat does, due to muscle’s water content. In this way, the researchers could determine a muscle mass index — the amount of muscle relative to height — similar to a body mass index. They looked at how this muscle mass index was related to the risk of death. …

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Big stride in understanding PP1, the ubiquitous enzyme

In the Proceedings of the National Academy of Sciences, a team of scientists at Brown University reports a major step forward in determining the specific behavior of the ubiquitous enzyme PP1 implicated in a wide range of diseases including cancer.PP1, whose role is to enable the passage of molecular messages among cells, is found pretty much everywhere in the body. Its wide range of responsibilities means it is essential to many healthy functions and, when things go wrong, to diseases. But its very versatility has prevented it from being a target for drug development, said Rebecca Page, associate professor of biology at Brown and the paper’s corresponding author.”The amazing thing about PP1 is that no one has wanted to touch it for the most part as a drug target because PP1 is involved in nearly every biological process,” Page said. “It’s not like you could just target the PP1 active site for, let’s say, diabetes because then you are going to affect drug addiction, Alzheimer’s disease and all these other diseases at the same time.”In other words, make a medicine to block PP1 in one bodily context and you’d ruin it in all other contexts. Structural biologists such as Page and Brown co-author Wolfgang Peti have therefore been eager to learn what makes PP1 behave in specific ways in specific situations.The key is the way PP1 binds with more than 200 different regulatory proteins. Scientists know of these proteins and know the sequences of amino acids that compose them, but they don’t know their structure or how they actually guide PP1.”The ability to predict how these PP1 interacting proteins bind PP1 from sequence alone is still missing,” Page and her colleagues wrote in PNAS.Now, through experiments in which her team including lead author Meng Choy combined NMR spectroscopy, X-ray crystallography and techniques in biochemistry, she has learned how PP1 binds to a targeting protein called PNUTS, forming “binding motifs.” That knowledge, combined with what she learned in earlier studies about two other targeting proteins — NIPP1 and spinophilin — has allowed her team to predict how PP1 binds with 43 of the 200 regulatory proteins that give it specific behavior.”What this work in conjunction with two of our previous structures allowed us to do was to define two entirely new motifs,” she said. “From that, comparing the sequences with the known proteins that interact with PP1 whose structures we don’t have, we were able to predict that 20 percent of them likely interact in a way that is similar to these three proteins.”So by resolving the structure of just three proteins with PP1, Page now has the means to understand the binding of many proteins without having to resolve their structure. Instead she need only know the few motifs and the proteins’ sequences.As for PP1’s interactions with the other 80 percent or so of regulatory proteins, those remain a mystery. But Page said the success her team has had in the lab working with PP1 and resolving key motifs makes her optimistic that those interactions can be solved, too.Story Source:The above story is based on materials provided by Brown University. Note: Materials may be edited for content and length.

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New approach to breast reconstruction surgery reduces opioid painkiller use, hospital stays

A new approach to breast reconstruction surgery aimed at helping patients’ bodies get back to normal more quickly cut their postoperative opioid painkiller use in half and meant a day less in the hospital on average, a Mayo Clinic study found. The method includes new pain control techniques, preventive anti-nausea treatment and getting women eating and walking soon after free flap breast reconstruction surgery. It has proved so effective, it is now being used across plastic surgery at Mayo Clinic. The findings were being presented at the Plastic Surgery Research Council annual meeting March 7-9 in New York.Breast reconstruction surgery is common after breast tissue is removed to prevent or treat breast cancer; in free flap breast reconstruction, the plastic surgeon transfers a section of tissue from one part of the body to the chest. Using traditional care, the hospital stay averaged roughly four and a half days after that procedure. Using a new approach known as an “enhanced recovery pathway,” patients spent an average of three days in the hospital, the researchers found.Opioid painkiller use by patients in the hospital after surgery also declined with the new method, and those patients reported less pain at 24 hours after surgery than those who received the traditional approach. Calculated in oral morphine equivalents, opioid use averaged 142.3 milligrams over the first three days in the hospital, compared with an average of 321.3 milligrams over the same period with traditional care.Patients are giving the changes positive reviews, says senior author Michel Saint-Cyr, M.D., a plastic surgeon in the Breast Diagnostic Clinic at Mayo Clinic in Rochester, Minn.”I think it minimizes their apprehension and anxiety preoperatively and they go into surgery with a better mindset. The majority do not think it was as painful as they thought it would be after surgery,” Dr. Saint-Cyr says. “We’re seeing pain scales ranging from 0 to 4 out of 10, compared to 6 to 8 out of 10 before the pathway. …

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Acupuncture holds promise for treating inflammatory disease

When acupuncture first became popular in the western hemisphere it had its doubters. It still does. But over time, through detailed observation, scientists have produced real evidence that ancient Chinese practitioners of the medical arts were onto something.Now new research documents a direct connection between the use of acupuncture and physical processes that could alleviate sepsis, a condition that often develops in hospital intensive care units, springs from infection and inflammation, and takes an estimated 250,000 lives in the United States every year.”Sepsis is the major cause of death in the hospital,” says Luis Ulloa, an immunologist at Rutgers New Jersey Medical School who led the study, which has been published by the journal Nature Medicine. “But in many cases patients don’t die because of the infection. They die because of the inflammatory disorder they develop after the infection. So we hoped to study how to control the inflammatory disorder.”The researchers already knew that stimulation of one of the body’s major nerves, the vagus nerve, triggers processes in the body that reduce inflammation, so they set out to see whether a form of acupuncture that sends a small electric current through that and other nerves could reduce inflammation and organ injury in septic mice. Ulloa explains that increasing the current magnifies the effect of needle placement, and notes that electrification is already FDA-approved for treating pain in human patients.When electroacupuncture was applied to mice with sepsis, molecules called cytokines that help limit inflammation were stimulated as predicted, and half of those mice survived for at least a week. There was zero survival among mice that did not receive acupuncture.Ulloa and his team then probed further, to figure out exactly why the acupuncture treatments had succeeded. And they made a discovery that, on its face, was very disappointing. They found that when they removed adrenal glands — which produce hormones in the body — the electroacpuncture stopped working. …

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Clutter cutter: Computer modeling used to understand how messy cells contribute to cancer

Life can be messy at all scales, requiring different organizational strategies — from cleaning the house, to removing damaged or expired cells from the body to avoid cancer progression.In a messy house, people use computers to manage paper and photo clutter; companies use computer systems to track their inventory. Now a team of researchers at Vanderbilt University in Nashville, Tenn., is taking a similar approach to cell-molecular inventory control for cancer. They have created computer models, using their programming framework (PySB), which enable them to explore the complex biochemical processes that drive cancer growth.”Our hypothesis is that understanding how the cell uses their protein inventory will lead to understanding why cells dysregulate and become carcinogenic. We expect model outputs will lead to novel, targeted cancer therapies — possibly by 2019,” explained researcher Carlos F. Lopez, who will present the work at the 58th annual Biophysical Society Meeting in San Francisco, Feb.15-19.Lopez is interested in understanding how cells in multicellular organisms engage programmed cell death — so-called “cell suicide” — for cellular removal. It is a natural part of many cells’ life cycle.When cancer cells avoid programmed cell death, uncontrolled growth fuels tumor progression. The Vanderbilt team expects their computer models to identify what goes wrong in these cases, at a speed and scale never before possible. Lopez noted: “We are bridging the nanoscale molecular-level biochemical interactions with the macroscale cancer tumor outcomes, which is a huge range in scales. Most people don’t realize this, but molecular chemical reactions at the nanometer and nanosecond level affect things that happen at the timescale level of years — nine orders of magnitude in space and time! For comparison, a nanosecond is to a second like a second is to one century.”Rather than listing the cellular biochemical reactions by hand, PySB enables the researchers to “write” the biochemical cellular processes as computer programs. …

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How gut bacteria communicate within our bodies, build special relationship

Communication is vital to any successful relationship. Researchers from the Institute of Food Research and the University of East Anglia have discovered how the beneficial bacteria in our guts communicate with our own cells.This is a key step in understanding how our bodies maintain a close relationship with the population of gut bacteria that plays crucial roles in maintaining our health, fighting infection and digesting our food.A study, published in the journal Cell Reports, shows that the gut bacteria produce an enzyme that modifies signalling in cells lining the gut. The enzyme also has another role in breaking down food components.”Our study provides a breakthrough in understanding how bacteria communicate across different kingdoms to influence our own cells’ behavior, as well as how we digest our food,” said Dr Regis Stentz from the IFR, which is strategically funded by the Biotechnology and Biological Sciences Research Council.We all rely on trillions of bacteria in our gut to break down certain components of our diet. One example is phytate, the form phosphorus takes in cereals and vegetables. Broken down phytate is a source of vital nutrients, but in its undigested form it has detrimental properties. It binds to important minerals preventing them being taken up by the body, causing conditions like anemia, especially in developing countries. Phytate also leads to excess phosphorus leaching into the soil from farm animal waste, and feed supplements are used to minimize this.But despite the importance of phytate, we know very little about how it is broken down in our gut. To address this Dr Stentz and colleagues screened the genomes of hundreds of different species of gut bacteria. They found, in one of the most prominent gut bacteria species, an enzyme able to break down phytate. In collaboration with Norwich Research Park colleagues at the University of East Anglia, they crystallized this enzyme and solved its 3D structure. …

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The number of tumor cells spread to sentinel lymph nodes affects melanoma prognosis

Cancer cell spread to the sentinel node — the lymph node to which cancer cells are most likely to spread from a primary tumor — is a risk factor for melanoma death. According to a study published in this week’s PLOS Medicine by Anja Ulmer, Christoph Klein and colleagues from the Universities of Tbingen and Regensburg, Germany, the prognosis of a patient largely depends on the number of disseminated cancer cells per million lymphocytes in the sentinel node. Even very low numbers were found to be predictive for reduced survival.The leading cause of death from skin disease is melanoma, which is the most dangerous type of skin cancer. When melanoma metastasizes and spreads to other parts of the body, treatment options become limited and the prognosis is poor. Melanoma staging (and prognosis) is currently focused on the primary tumor itself, with characteristics like tumor thickness, mitotic rate, and ulceration (break in the skin caused by the tumor) indicating the likelihood that the tumor has started to spread. Looking for tumor cells in the sentinel nodes is done for patients who are at increased risk for spread, but standard procedures for how to measure spread to the nodes and how to integrate this information with the tumor histology are needed. Since melanoma is one of the deadliest cancers, better predictors of prognosis for melanoma patients are needed for patient information and to determine treatment options.The researchers prospectively collected a large number of samples for this relatively rare cancer: 1,834 sentinel lymph nodes from 1,027 patients with melanoma who had been followed for 5 years after the samples were taken. They labelled disseminated cancer cells (DCCs) in the lymph nodes through the use of a marker for melanoma cells, counted them, and calculated DCC density. They then asked whether DCC density was related to a patient’s survival. They found that patients with high DCC density in the lymph nodes were more likely to die from melanoma within 5 years. …

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Scientists chip away at mystery of what lives in our mouths

Scientists have pieced together sections of DNA from 12 individual cells to sequence the genome of a bacterium known to live in healthy human mouths.With this new data about a part of the body considered “biological dark matter,” the researchers were able to reinforce a theory that genes in a closely related bacterium could be culprits in its ability to cause severe gum disease.Why the dark matter reference? More than 60 percent of bacteria in the human mouth refuse to grow in a laboratory dish, meaning they have never been classified, named or studied. The newly sequenced bacterium, Tannerella BU063, is among those that to date have not successfully been grown in culture — and its genome is identified as “most wanted” by the Human Microbiome Project.The federal Human Microbiome Project aims to improve research about the microbes that play a role in health and disease. Those 12 cells of BU063 are a good example of the complexity of life in the mouth: They came from a single healthy person but represented eight different strains of the bacterium.BU063 is closely related to the pathogen Tannerella forsythia, a bacterium linked to the gum disease periodontitis. Despite being “cousins,” this research revealed that they have clear differences in their genetic makeup.Those genes lacking in BU063 but present in forsythia — meaning they are a likely secret behind forsythia’s virulence — are now identified as good targets for further study, researchers say.”One of the tantalizing things about this study was the ability to do random searches of other bacteria whose levels are higher in periodontitis,” said Clifford Beall, research assistant professor of oral biology at The Ohio State University and lead author of the study. “We looked for genes that were present in these bacteria and forsythia and not in BU063. There is one particular gene complex in a whole list of these periodontitis-related bacteria that could be involved with virulence.”The research is published in the journal PLOS ONE.Periodontitis results when extensive inflammation or infection of the gums spreads beyond the gums to damage structures that support the teeth, including bone. Pockets that form between the gums and teeth are filled with different kinds of bacteria. Treatment typically involves deep cleaning or surgery to remove these infected pockets. Because multiple bacteria are associated with the disease, antibiotics have not been considered effective for treatment.And though many bacteria in these pockets have been collected and at least partially identified, their characteristics remain a mystery.”We think some of the gene differences we’ve found in this study are important, but it’s still not clear what all these genes do, meaning we still don’t know why certain bacteria in periodontitis are pathogenic in the first place. …

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Embryology: Scientists crack open ‘black box’ of development and see a ‘rosette’

We know much about how embryos develop, but one key stage — implantation — has remained a mystery. Now, scientists from Cambridge have discovered a way to study and film this ‘black box’ of development. Their results — which will lead to the rewriting of biology text books worldwide — are published in the journal Cell.Embryo development in mammals occurs in two phases. During the first phase, pre-implantation, the embryo is a small, free-floating ball of cells called a blastocyst. In the second, post-implantation, phase the blastocyst embeds itself in the mother’s uterus.While blastocysts can be grown and studied outside the body, the same has not been true from implantation. And because embryos are so closely connected to their mothers, implantation has also been difficult to study in the womb.According to study author Professor Magdalena Zernicka-Goetz of the University of Cambridge: “We know a lot about pre-implantation, but what happens after implantation — and particularly the moment of implantation — is an enigma.”Scientists are interested in studying implantation because the embryo undergoes huge changes in such a short space of time.”During these two days, it goes from a relatively simple ball to a much larger, more complex cup-like structure, but exactly how that happens was a mystery — a black box of development. That is why we needed to develop a method that would allow us to culture and study embryos during implantation,” she explained.Working with mouse cells, Professor Zernicka-Goetz and her colleague Dr Ivan Bedzhov succeeded in creating the right conditions outside the womb to study the implantation process.To be able to support development, they created a system comprising a gel and medium that, as well as having the right chemical and biological properties, was of similar elasticity to uterine tissue. Crucially, this gel was transparent to optical light, allowing then to film the embryo during implantation.This new method revealed that on its way from ball to cup, the blastocyst becomes a ‘rosette’ of wedge-shaped cells, a structure never before seen by scientists.”It’s a beautiful structure. This rosette is what a mouse looks like on the 4th day of its life, and most likely what we look like on the 7th day of ours, and it’s fascinating how beautiful we are then, and how these small cells organise so perfectly to allow us to develop.”As well as answering a fundamental question in developmental biology, the new method will allow scientists to study embryo growth and development at implantation for the first time, which could help improve the success of IVF, and extend our knowledge of stem cells, which could advance their use in regenerative medicine.The findings also mean developmental biology text books will need rewriting. “The text books make an educated guess of what happened during this part of development, but we now know that what I learned and what I teach my students about this was totally wrong,” said Professor Zernicka-Goetz.Story Source:The above story is based on materials provided by University of Cambridge. …

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‘Sexy’ underwear is not the only way to feel feminine on Valentine’s Day

TV makeover shows and glossy magazines can leave women feeling guilty for not wearing “sexy” lingerie – especially on Valentine’s Day.But in fact, many different types of underwear could make them feel feminine, according to an expert on underwear consumption.Dr Christiana Tsaousi, a lecturer in marketing and consumption at the University of Leicester’s School of Management, believes underwear choices are hugely affected by personal taste influenced by social background, professional status and upbringing, and why every woman’s underwear needs are individual.Her research on the subject is published today by SAGE in the Journal of Consumer Culture.The ‘shaping’ underwear, for example, prescribed by reality TV shows, such as How To Look Good Naked and 10 Years Younger, is an unhelpful way of thinking about how women should choose what they wear, Dr Tsaousi has concluded.”On Valentine’s Day, some women may feel the only way to feel feminine is to wear the “sexy” underwear promoted by the media in general. But this is really not the case.”“Reality makeover shows and media in general have one purpose – to make women look feminine in line with western ideals,” she said.“They present femininity as this thing where you feel nice about yourself because you have a body that needs to be expressed. Having that as an aim, participants on the shows are given underwear that’s going to mould the body in a certain way.”But Dr Tsaousi, who has conducted extensive research into the consumption of underwear, says that women think very carefully about choosing the right underwear for the right situation – and that comfort is often as important as “sexiness”.“Women learn to choose underwear for the right situation. In an ideal world, it would be good if reality shows acknowledge that women can feel feminine by wearing different underwear.“Some women don’t like these shows because they always show a specific type of femininity, which is not the reality in most cases. They can make you feel guilty about the way you look and the way you feel about your body if you aren’t wearing underwear considered sexy.“When partners are looking to buy underwear as Valentine’s gifts for their wives or girlfriends, they should choose underwear which will fit their partners well and will make them feel comfortable – rather than the stereotypical tiny, uncomfortable types. This will ultimately lead to them feeling nice about themselves.”In her new paper for the Journal of Consumer Culture, Dr Tsaousi interviewed women from a wide range of groups and backgrounds, including university lecturers, young mums, and female rugby players. She looked at the influence of women’s upbringing, profession, age, and social status on their underwear choices.She found that some groups such as the young rugby girls favoured “cute” underwear while for others such as academics something that supports their professional dress was the main priority.“The paper indicates that women’s choices in underwear are determined by factors such as our ways of thinking, up-bringing, taste and status in society,” Dr Tsaousi said. “The paper also suggests that women make similar judgements about their underwear as they would their outerwear.”For many women another big influence on their taste in underwear is their mother.“We can’t forget that the mother normally buys the first bra for her daughter. It is the first act of being feminine, and introduces girls to the idea that they are becoming a woman,” Dr Tsaousi said.Dr Tsaousi added that the study of the consumption of underwear is an area which has not been explored in detail by academics – but is very important to the market.“Obviously women’s outer dress is visible so it is under scrutiny by others. Underwear on the other hand is hidden but people make similar judgements.“Other forms of dress have been widely discussed in consumption studies, but underwear is an area that hasn’t been fully researched. …

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Scientists reprogram skin cells into insulin-producing pancreas cells

A cure for type 1 diabetes has long eluded even the top experts. Not because they do not know what must be done — but because the tools did not exist to do it. But now scientists at the Gladstone Institutes, harnessing the power of regenerative medicine, have developed a technique in animal models that could replenish the very cells destroyed by the disease. The team’s findings, published online today in the journal Cell Stem Cell, are an important step towards freeing an entire generation of patients from the life-long injections that characterize this devastating disease.Type 1 diabetes, which usually manifests during childhood, is caused by the destruction of -cells, a type of cell that normally resides in the pancreas and produces a hormone called insulin. Without insulin, the body’s organs have difficulty absorbing sugars, such as glucose, from the blood. Once a death sentence, the disease can now be managed with regular glucose monitoring and insulin injections. A more permanent solution, however, would be to replace the missing -cells. But these cells are hard to come by, so researchers have looked towards stem cell technology as a way to make them.”The power of regenerative medicine is that it can potentially provide an unlimited source of functional, insulin-producing -cells that can then be transplanted into the patient,” said Dr. Ding, who is also a professor at the University of California, San Francisco (UCSF), with which Gladstone is affiliated. “But previous attempts to produce large quantities of healthy -cells — and to develop a workable delivery system — have not been entirely successful. …

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Toxin in seafood causes kidney damage in mice at levels considered safe for consumption

A chemical that can accumulate in seafood and is known to cause brain damage is also toxic to the kidneys, but at much lower concentrations. The findings, which come from a study appearing in an upcoming issue of the Journal of the American Society of Nephrology (JASN), suggest that officials may need to reconsider what levels of the toxin are safe for human consumption.The world’s oceans contain algae that produce certain chemicals that can be harmful to humans and other living creatures. Many of these chemicals are considered neurotoxins because they cause damage to the brain. The neurotoxin domoic acid, also called “Amnesic Shellfish Poisoning,” is a very stable, heat resistant toxin that is becoming more prominent in coastal regions, likely due to environmental changes. It can accumulate in mussels, clams, scallops, and fish, and the FDA has set a legal limit of domoic acid in seafood based primarily on its adverse neurological effects.Because domoic acid is cleared from the body by the kidneys, P. Darwin Bell, PhD, Jason Funk, PhD (Medical University of South Carolina), and their colleagues looked to see if the toxin might also have detrimental effects on these organs. By giving mice varying doses of domoic acid and the assessing animals’ kidney health, the team found that the kidney is much more sensitive to this toxin than the brain.”We have found that domoic acid damages kidneys at concentrations that are 100 times lower than what causes neurological effects,” said Dr. Bell. “This means that humans who consume seafood may be at an increased risk of kidney damage possibly leading to kidney failure and dialysis.” While the findings need to be verified in humans, the researchers would like to see increased awareness and monitoring of domoic acid levels in all seafood. They say that the FDA may also need to reconsider the legal limit of domoic acid in food due to its kidney toxicity.Story Source:The above story is based on materials provided by American Society of Nephrology (ASN). …

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What falling in love does to your heart and brain

Getting struck by Cupid’s arrow may very well take your breath away and make your heart go pitter-patter this Valentine’s Day, reports sexual wellness specialists at Loyola University Health System.”Falling in love causes our body to release a flood of feel-good chemicals that trigger specific physical reactions,” said Pat Mumby, PhD, co-director of the Loyola Sexual Wellness Clinic and professor, Department of Psychiatry & Behavioral Neurosciences, Loyola University Chicago Stritch School of Medicine (SSOM). “This internal elixir of love is responsible for making our cheeks flush, our palms sweat and our hearts race.”Levels of these substances, which include dopamine, adrenaline and norepinephrine, increase when two people fall in love. Dopamine creates feelings of euphoria while adrenaline and norepinephrine are responsible for the pitter-patter of the heart, restlessness and overall preoccupation that go along with experiencing love.MRI scans indicate that love lights up the pleasure center of the brain. When we fall in love, blood flow increases in this area, which is the same part of the brain implicated in obsessive-compulsive behaviors.”Love lowers serotonin levels, which is common in people with obsessive-compulsive disorders,” said Mary Lynn, DO, co-director of the Loyola Sexual Wellness Clinic and assistant professor, Department of Obstetrics & Gynecology, SSOM. “This may explain why we concentrate on little other than our partner during the early stages of a relationship.”Doctors caution that these physical responses to love may work to our disadvantage.”The phrase ‘love is blind’ is a valid notion because we tend to idealize our partner and see only things that we want to see in the early stages of the relationship,” Dr. Mumby said. “Outsiders may have a much more objective and rational perspective on the partnership than the two people involved do.”There are three phases of love, which include lust, attraction and attachment. Lust is a hormone-driven phase where we experience desire. Blood flow to the pleasure center of the brain happens during the attraction phase, when we feel an overwhelming fixation with our partner. This behavior fades during the attachment phase, when the body develops a tolerance to the pleasure stimulants. …

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Do you have a sweet tooth? Honeybees have a sweet claw

New research on the ability of honeybees to taste with claws on their forelegs reveals details on how this information is processed, according to a study published in the open-access journal, Frontiers in Behavioral Neuroscience.Insects taste through sensilla, hair-like structures on the body that contain receptor nerve cells, each of which is sensitive to a particular substance. In many insects, for example the honeybee, sensilla are found on the mouthparts, antenna and the tarsi — the end part of the legs. Honeybees weigh information from both front tarsi to decide whether to feed, finds the latest study led by Dr. Gabriela de Brito Sanchez, researcher, University of Toulouse, and Dr. Martin Giurfa, Director of the Research Centre on Animal Cognition, University of Toulouse, France.Hundreds of honeybees were included in the study. Sugary, bitter and salty solutions were applied to the tarsi of the forelegs to test if this stimulated the bees to extend or retract their tongue — reflex actions that indicate whether or not they like the taste and are preparing to drink. Results revealed that honeybee tarsi are highly sensitive to sugar: even dilute sucrose solutions prompted the bees to extend their tongue. Measurements of nerve cell activity showed that the part of the honeybee tarsus most sensitive to sugary tastes is the double claw at its end. Also, the segments of the tarsus before the claws, known as the tarsomeres, were found to be highly sensitive to saline solutions.”Honeybees rely on their color vision, memory, and sense of smell and taste to find nectar and pollen in the ever-changing environment around the colony,” says Dr. Giurfa. …

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