A new study appearing finds that ketamine’s acute antidepressant effect requires opioid system activation, the first time that a receptor site has been shown in humans to be necessary for any antidepressant’s mechanism of action. While opioids have been used historically to treat depression, they are known to carry a high risk of dependence. Alan F. Schatzberg, M.D., who led this research at Stanford, cautions against widespread and repeated use of ketamine for depression treatment until more research can be done on both the mechanism of action and the risk of tolerance, abuse and dependence.
Previous research has found ketamine to have rapid-onset antidepressant effects. While the specific mechanism of action for these effects was unknown, it had been generally thought to be due to NMDA receptor antagonism. Since many efforts to develop NMDA antagonists as antidepressants have been unsuccessful, this new study aimed at determining the role of the opioid system in ketamine’s antidepressant and dissociative effects in adults with treatment-resistant depression.
Nolan R. Williams, M.D., and Boris D. Heifets, M.D., Ph.D., from Stanford University, co-first authors of the article, hypothesized that ketamine’s antidepressant effects may be related to intrinsic opioid receptor properties of ketamine. The study looked at whether use of naltrexone, an opioid blocker, prior to ketamine treatment would reduce the acute antidepressant effects of the ketamine or its dissociative effects. The researchers conducted a randomized double-blind crossover trial involving individuals with treatment-resistant depression. Participants received the opioid blocker or a placebo prior to ketamine infusion treatment. Twelve participants completed both conditions in randomized order.
Use of naltrexone dramatically blocked the antidepressant effects of the ketamine but not the dissociative effects, so the trial was halted at the interim analysis. Participants receiving the ketamine plus naltrexone experienced much less reduction in depression symptoms than participants receiving ketamine plus placebo. There were no differences in ketamine-induced dissociation between those receiving naltrexone or a placebo.

American Psychiatric Associationhttps://tinyurl.com/yaon4xuw

A new study led by ANU has discovered a promising way to significantly lower doses of X-rays that has the potential to revolutionize 3D medical imaging and make screening for early signs of disease much cheaper and safer.
The research team, which involved the European Synchrotron Radiation Facility and Monash University, built upon an unconventional imaging approach known as “ghost imaging” to take 3D X-ray images of an object’s interior that is opaque to visible light.
Lead researcher Dr Andrew Kingston said the study was the first to achieve 3D X-ray imaging using the ghost imaging approach, which has the potential to make 3D medical imaging much cheaper, safer and more accessible.    
“The beauty of using the ghost imaging technique for 3D imaging is that most of the X-ray dose is not even directed towards the object you want to capture – that’s the ghostly nature of what we’re doing,” said Dr Kingston from the ANU Research School of Physics and Engineering.
“There’s great potential to significantly lower doses of X-rays in medical imaging with 3D ghost imaging and to really improve early detection of diseases like breast cancer.”
Too much radiation from medical X-ray imaging can increase cancer risk, which limits how often patients can be tested with CT systems, 3D mammography for breast cancer screening and other 3D X-ray approaches.
“A variation of our approach doesn’t require an X-ray camera at all, just a sensor – this would make a 3D medical imaging setup much cheaper,” Dr Kingston said.
The proof-of-concept approach took a 3D ghost image of a simple object of 5.6mm diameter at a relatively low resolution of about 0.1mm.
The researchers devised a new ghost imaging measurement system that used a series of X-ray beams with patterns.
Each beam was then split into two identical beams. The pattern was recorded in the primary beam, which acted as a reference since it never passed through the object that the researchers were imaging. The secondary beam passed through the object, with only the total X-ray transmission measured by a single sensor.
The researchers then used a computer to create a 2D X-ray projection image of the object from these measurements.
This process was repeated with the object at different orientations to construct a 3D image.
“Our most important innovation is to extend this 2D concept to achieve 3D imaging of the interior of objects that are opaque to visible light,” Dr Kingston said.
“3D X-ray ghost imaging, or ghost tomography, is a completely new field, so there’s an opportunity for the scientific community and industry to work together to explore and develop this exciting innovation.”
Co-researcher Professor David Paganin from Monash University said the team’s achievement could be compared to the early days of electron microscopes, which could only achieve a magnification of 14 times.
“This result was not as good as could be obtained with even the crudest of glass lenses using visible light,” he said.
“However, the microscope using electrons rather than light had the potential – realised only after decades of subsequent development – to see individual atoms, which are much tinier than an ordinary microscope using visible light can see.”

Australian National Universityhttps://tinyurl.com/y7xeop7k

Infants with diabetes can drop insulin syringes. Researchers from Bergen and Exeter have been leading the work, which causes children worldwide to replace insulin syringes with tablets.
"All infants diagnosed with diabetes before 6-7 months of age should be given a rapid gene test to change treatment as soon as possible from insulin to sulfonylurea tablets. They can expect a long and very good effect of the treatment of blood sugar control, and the treatment is safe," says Professor Pål Rasmus Njølstad at the University of Bergen.
It was in 2004 discovered that relatively high doses of sulfonylurea tablets could be used to treat diabetes in infants. This principle has given a new life for children with this type of diabetes, because 90% can stop insulin injections and even achieve better blood sugar control, at least for one year without the same low blood sugar problem. However, it has been unknown whether this treatment can be maintained in the long term, especially as sulfonylureas fail in half of those with type 2 diabetes after five years of treatment.
The results are now available from an international multi-center study from centers in Bergen, Exeter, Rome, Paris, and Krakow. This included 81 people who 10 years ago had changed the treatment from insulin to sulfonylurea tablets. It was found that the failure effect of treatment, which is often seen in type 2 diabetes, rarely exists in this type of infant diabetes. Sulfonylurea is safe in this treatment, even with the relatively high doses needed. An excellent control of blood glucose was retained after ten years of treatment. Some children initially experienced a certain recovery of neurological features, but most of them did not have any clear improvement in the problems.
"These findings will give many children a new and better quality of life," says Njølstad. "This is one of the few examples of lasting effect of precision medicine."

ScienceDaily
www.sciencedaily.com/releases/2018/06/180607101013.htm

Infants born to women exposed to high levels of air pollution in the week before delivery are more likely to be admitted to a newborn intensive care unit (NICU), suggests an analysis by researchers at the National Institutes of Health. Depending on the type of pollution, chances for NICU admission increased from about 4% to as much as 147%, compared to infants whose mothers did not encounter high levels of air pollution during the week before delivery. The study was led by Pauline Mendola, Ph.D., of the Epidemiology Branch at NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development.
 “Short-term exposure to most types of air pollutants may increase the risk for NICU admission,” Dr. Mendola said. “If our findings are confirmed, they suggest that pregnant women may want to consider limiting their time outdoors when air quality advisories indicate unhealthy conditions.”
Previous studies have linked elevated levels of certain kinds of air pollutants to higher risks for gestational diabetes and preeclampsia, a blood pressure disorder of pregnancy. Earlier research also has shown that infants born to women exposed to high levels of air pollutants are at risk for preterm birth, of being small for their gestational age at birth and of growing more slowly than normal in the uterus. Given these associations, the study authors sought to determine whether prenatal exposure to air pollution might increase the chance for NICU admission.
Researchers analysed data from the Consortium on Safe Labor, which compiled information on more than 223,000 births at 12 clinical sites in the United States from 2002 to 2008. They linked records from more than 27,000 NICU admissions to data modified from the Community Multiscale Air Quality Modeling System, which estimates environmental pollution concentrations in the United States. Researchers matched air quality data in the area where each birth occurred to the week before delivery, the day before delivery and the day of delivery. They then compared these time intervals to air quality data two weeks before delivery and two weeks after delivery to identify risk of NICU admission associated with pollution levels.
The researchers also examined the odds of NICU admission associated with high concentrations of particulate matter (pollution particles) less than 2.5 microns in diameter (PM2.5). These types of particles originate from various sources, among them diesel and petrol engines, power plants, landfills, sewage facilities and industrial processes. Exposure to high concentrations of organic compounds in the air was associated with a 147% increase in risk of NICU admission. Elemental carbon and ammonium ions presented similar increases in risk (35% and 37%, respectively), while exposure to nitrate compounds was associated with a 16% higher risk of NICU admission.
Chances of NICU admission increased significantly with exposures to traffic-related pollutants on the day before and the day of delivery, compared to the week before delivery: 4% and 3%, respectively, for an approximately 300 parts per million (ppm) increase in carbon monoxide; 13% and 9% for an approximately 26 ppm increase in nitrogen dioxide; and 6% and 3% for an approximately 3 ppm increase in sulphur dioxide.
Researchers do not know why exposure to air pollution might increase the chances for NICU admission. They theorize, however, that pollutants increase inflammation, leading to impaired blood vessel growth, particularly in the placenta, which supplies oxygen and nutrients to the developing fetus.
Eunice Kennedy Shriver National Institute of Child Health and Human Developmenthttps://tinyurl.com/y3flll6e