Patients with major depressive disorder (MDD) have increased brain levels of a marker of microglial activation, a sign of inflammation, according to a new study in Biological Psychiatry by researchers at the University of Manchester, United Kingdom. In the study, Dr. Peter Talbot and colleagues found that the increase in the inflammatory marker was present specifically in patients with MDD who were experiencing suicidal thoughts, pinning the role of inflammation to suicidality rather than a diagnosis of MDD itself. "Our findings are the first results in living depressed patients to suggest that this microglial activation is most prominent in those with suicidal thinking," said Dr. Talbot. Previous studies suggesting this link have relied on brain tissue collected from patients after death. "This paper is an important addition to the view that inflammation is a feature of the neurobiology of a subgroup of depressed patients, in this case the group with suicidal ideation," said Dr. John Krystal, Editor of Biological Psychiatry. "This observation is particularly important in light of recent evidence supporting a personalized medicine approach to depression, i.e.., that anti-inflammatory drugs may have antidepressant effects that are limited to patients with demonstrable inflammation."
Name one civilization located in the Americas that pre-dates the arrival of Europeans. You probably replied with the Aztecs, the Inca or perhaps the Maya. A new paper, published in De Gruyter’s open access journal Open Archeology, by Michael E. Smith of Arizona State University shows how this view of American civilizations is narrow. It is entitled “The Teotihuacan Anomaly: The Historical Trajectory of Urban Design in Ancient Central Mexico”. Smith, using a map produced by the Teotihuacan mapping project, conducted a comparative analysis of the city with earlier and later Mesoamerican urban centers and has proved, for the first time, the uniqueness of the city. The paper outlines how the urban design of the city of Teotihuacan differed from past and subsequent cities, only to be rediscovered and partially modelled on many centuries later by the Aztecs.
Researchers at the University of Bristol have been taking a close-up look at the biting mouthparts of the African tsetse fly as part of ongoing work on the animal diseases it carries. Using the new high-powered scanning electron microscope in the University’s Life Sciences Building, researchers from the Trypanosome Research Group were able to see the rows of sharp teeth and rasps that the fly uses to chew through the skin when it bites. The teeth tear the delicate blood capillaries in the skin, so the fly can suck up the blood. To stop the blood clotting, the fly squirts saliva containing anti-coagulant into the wound through a narrow tube inside the proboscis. To their surprise, the researchers found that the tip of this tube is decorated with intricate finger-like structures with suckers. Professor Wendy Gibson from the School of Biological Sciences, led the research which has been published this week in the journal Parasites & Vectors. She said “This was an unexpected finding – the textbooks just show a plain pointed end to the saliva tube.
A new treatment for osteoporosis provides major improvements in bone density and more effective protection against fractures than the current standard treatment. These are the findings of a study published in the New England Journal of Medicine (NEJM). The study is the first that compares the effect of two osteoporosis medicines on fractures. “With the new treatment, we could offer significantly better protection against fractures and could thereby help many patients with severe osteoporosis,” says co-author of the study Mattias Lorentzon, Professor of Geriatrics at the Institute of Medicine, Sahlgrenska Academy, and Senior Physician at Sahlgrenska University Hospital. Many patients with severe osteoporosis and a high risk of fractures often cannot regain their original bone strength. They continue to have fractures even with treatment according to current standards with alendronate in tablet form every week.
iPS-derived neural stem cells in green and neurons in red from a healthy individual (to the left) and a person with lissencephaly (to the right). The sample from the healthy person gives rise to fewer immature cells (neural stem cells). Photo: Falk Laboratory
By reprogramming skin cells into nerve cells, researchers at Karolinska Institutet are creating cell models of the human brain. In a new study published in Molecular Psychiatry the researchers describe how cells from patients with the severe developmental disease lissencephaly differ from healthy cells. The method can provide vital new knowledge on difficult-to-study congenital diseases. Lissencephaly is a rare congenital developmental disease that can be caused by, amongst other anomalies, a mutation of the DCX gene. Affected individuals are born with serious developmental disabilities and a brain that is smooth instead of folded. The discovery that it is possible to reprogramme specialised cells such as skin cells in order to reverse their development back to stem cells was rewarded with the 2012 Nobel Prize. The resulting so-called iPS-cells (induced pluripotent stem cells) can then be turned into other specialised cell types. Anna Falk, docent at Karolinska Institutet’s Department of Neuroscience, uses this technique to build cell models of the human brain. In the present study, her team took skin cells from patients with lissencephaly and turned them into iPS cells, which they then cultivated under special conditions into neuronal stem cells and neurons that are copies of those in the patients’ brains.
Even Charles Darwin, the author of “The Origin of Species”, had a problem with species. “I was much struck how entirely vague and arbitrary is the distinction between species and varieties,” Darwin wrote in his seminal 1859 work.
Categorizing species can get especially hazy at small, microbial scales. After all, the classical definition of species as interbreeding individuals with sexually viable offspring doesn’t apply to asexual organisms. Examining shared DNA doesn’t help either: collectively, E. Coli bacteria have only 20 percent of genes in common. The classification process gets even trickier as many microbes work so closely that it is unclear what to call separate organisms, let alone separate species. The woes of classification generate contentious debates in the biology community. But, for postdoctoral fellow Mikhail Tikhonov, one field’s contentious debate is another’s theoretical playground. In new research, he asks: Could organism interactions be described without mentioning species at all?
Scientists at the University of Southampton have made a significant discovery in efforts to develop a vaccine against Zika, dengue and Hepatitis C viruses that affect millions of people around the world.
In a study published in Science Immunology, researchers have shown that natural killer cells (NK cells), which are a fundamental part of the body’s immune system, can recognise many different viruses including global pathogens such as Zika, dengue and Hepatitis C viruses, through a single receptor called KIR2DS2.
Lead researcher Salim Khakoo, Professor of Hepatology, said the findings are very exciting and could change the way viruses are targeted by vaccines but warned that the research is still at an early stage, and animal studies/clinical trials will be needed to test the findings.
Vaccines work by stimulating the immune response to the coat of proteins on the virus enabling the body to fight off the virus and recognise it in the future. However, the viruses are able to change their coat proteins, helping the virus to evade the antibodies, meaning some viruses can be very hard to vaccinate against.
Climatological model surface circulations in February: (a) for 1990–1995 and (b) for 1995–2000. The colour bar represents the surface current speed, while arrows show both speed and direction
Using a model developed at the JRC, scientists have successfully simulated the Black Sea’s long term currents, salt water content and temperature for the first time.Average surface temperatures of the Black Sea may not have risen, according to the surprising results of a new study from the JRC. The study used a model to simulate possible temperature changes and predict long term trends in the Black Sea’s hydrodynamics. While the surface showed no long term warming trend, the same simulations also indicated that average temperatures at 50 metres below the surface may be rising. The Black Sea has unique natural conditions like a positive net freshwater balance and very specific local currents. Observational data on temperature change is varied and scarce. As such it is not clear what the impacts of climate change have been on Black Sea water temperatures.
The organic pollution decomposing properties of titanium dioxide (TiO2) have been known for about half a century. However, practical applications have been few and hard to develop, but now a Greek paint producer claims to have found a solution. The photocatalytic properties of anatase, one of the three naturally occurring forms of titanium dioxide, were discovered in Japan in the late 1960s. Under the influence of the UV-radiation in sunlight, it can decompose organic pollutants such as bacteria, fungi and nicotine, and some inorganic materials into carbon dioxide. The catalytic effect is caused by the nanostructure of its crystals. Applied outdoors, this affordable and widely available material could represent an efficient self-cleaning solution for buildings. This is due to the chemical reaction, which leaves a residue on building façades, a residue then washed away when it rains. Applying it to monuments in urban areas may save our cultural heritage, which is threatened by pollutants.
Early weaning increases aggression and stereotypic behaviour in cats, shows a new study from Professor Hannes Lohi’s research group. Based on the study conducted at the University of Helsinki, the recommended weaning age of 12 weeks should be raised by at least two weeks. Delaying weaning is an easy and cost-efficient way of improving the quality of life of cats. The cat is the most popular companion animal, and people are increasingly interested in its wellbeing. One of the topics under international debate is the weaning age, i.e., the age at which kittens are separated from their mother and siblings and brought to a new home. In Finland, the recommended minimum age of weaning is 12 weeks, but in many other countries, such as the United States, weaning of kittens as young as 8 weeks is common. It has previously been thought that the critical period of socialisation in cats ends by 8 weeks of age, after which social experiences have little impact on behaviour.