Day: October 5, 2022

Categories : Diseases, Syndromes and Conditions Metabolic DisordersTags :

Strong Link of Type 1 Diabetes to Enterovirus Infection

On By ModernMedia
A 3D map of the islets in the human pancreas. Source: Wikimedia

A meta-analysis of molecular studies found a strong link between enterovirus infection and type 1 diabetes. Across 48 abstracts on the topic, people with type 1 diabetes were nearly eight times more likely to have an enterovirus infection than those with normal pancreatic function, according to a presentation at the European Association for the Study of Diabetes (EASD) meeting.

For this review, researchers examined 56 studies using molecular methods to identify enterovirus infection by looking for viral nucleic acid or protein in a human clinical sample.

People with islet autoimmunity were twice as likely to have had an enterovirus infection at any point in time, based on data from 18 studies.

Subgroup analysis of people who were diagnosed with the enterovirus within the past month found 16.22-fold higher odds of recent-onset type 1 diabetes, based upon 28 studies.

“This is very recent onset type 1 diabetes, and that was the highest risk group that we detected,” reported Sonia Isaacs, PhD candidate, of University of New South Wales in Australia, during a press conference.

Looking more closely at other subgroup criteria revealed associations.

First, those who had any islet autoimmunity and eventually progressed to full-blown type 1 diabetes were over five times more likely to have an enterovirus infection than controls; this was a higher risk than those who had islet autoimmunity and never progressed to type 1 diabetes. When it came to timing, only infections at the time of or after islet autoimmunity seroconversion carried higher risk (OR 5.1), whereas the increased risk wasn’t significant for infections prior to seroconversion.

Isaacs noted that those with a familial risk of type 1 diabetes (ie in a first-degree relative) also had a much higher risk for an enterovirus infection (OR 9.8), higher than the subgroup recruited for having a high-risk HLA gene. Those who had the high-risk HLA gene and a familiar risk of type 1 diabetes had 141.1-times higher odds of prior enterovirus infection.

Having several enterovirus infections was also linked with a doubled chance of islet autoimmunity.

Specific type of enterovirus linked to risk of type 1 diabetes included:

  • Enterovirus A: OR 3.7
  • Enterovirus B: OR 12.7
  • Enterovirus C: OR 13.8

“This is where the coxsackieviruses come from,” Isaacs pointed out. “Coxsackievirus B1 and B4 stood out.”

Isaacs suggested the possibility of enterovirus vaccinations and antivirals as a prevention strategy for type 1 diabetes.

Source: MedPage Today

Categories : Mental Health Obstetrics & GynaecologyTags :

Biological Changes in Mothers Experiencing Postpartum Depression

On By ModernMedia
Woman with depression
Photo by Sydney Sims on Unsplash

Newly discovered biological changes in mothers who suffer postpartum depression may help explain the condition, yield long-sought treatments and let doctors identify those at risk even before their babies are born. The findings were published in Molecular Psychiatry.

Postpartum depression strikes up to 20% of new mothers, and roughly 20% of maternal deaths after childbirth are from suicide. Postpartum depression can cause anxiety and irritability, feelings of self-doubt and difficulty bonding with the baby, cognitive impairment, and interfering with sleeping and eating. For the child, maternal postpartum depression can lead to cognitive, emotional and social development problems.

Risk factors for postpartum depression are thought to include the mother’s age at childbirth, diabetes and prior history of mental health issues. But the new discovery suggests a previously unknown biological contributor: an impairment of the body’s ability to clean up old genetic material and other cellular debris.

“The finding that cells aren’t cleaning out old proteins and cellular debris, called autophagy, occurs before women develop depression symptoms, indicating that it could be part of the disease process,” explained Jennifer L. Payne, MD, director of the Reproductive Psychiatry Research Program at the University of Virginia School of Medicine. “There are several medications that promote autophagy in cells, so this finding might open the door to new treatments and to identification of women at risk of postpartum depression before they become ill.”

Understanding Postpartum Depression

Dr Payne and colleagues wanted to determine if ‘extracellular RNA communication’, a newly discovered form of communication among cells, might contribute to postpartum depression. Extracellular RNA communication is heightened during pregnancy and is critical in embryo implantation and in the body’s inflammatory response afterward.

The researchers analysed blood plasma samples from 14 research participants with and without postpartum depression, collected during and after their pregnancies. The researchers found that extracellular RNA communication in immune cells was altered extensively in women who suffered postpartum depression. Further, they determined that this “large and consistent” change significantly limited the women’s bodies’ ability to perform important cellular cleanup – suggesting a potential biological cause for their depression.

“Deficits in autophagy are thought to cause toxicity that may lead to the changes in the brain and body associated with depression,” Dr Payne said. “We have never fully understood the biological basis for postpartum depression, and this finding gets us closer to an understanding.”

Source: University of Virginia Health System

Categories : Uncategorized

Study Reveals How Psychostimulants Affect Attention and Learning

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Photo by Myriam Zilles on Unsplash

Psychostimulants are commonly used as treatments of psychiatric disorders or to improve cognition, but the benefits of these drugs are not the same for everyone, as their effects vary greatly both across individuals and within the same patient. This variability hinders treatment strategies in psychiatry, and the reasons behind it are still not clear. Now, a study published in PNAS, researchers reported advances in understanding why this is.

One such psychostimulant is methylphenidate (Ritalin), which is used to treat attention deficit hyperactivity disorder (ADHD), and has significant variability in efficacy. In addition to treating ADHD, methylphenidate is widely used by healthy people for its cognition-improving effects. Methylphenidate acts in part by increasing levels of dopamine, a neurotransmitter involved in the brain’s reward system. 

The researchers tested the hypothesis that the effects of methylphenidate on learning based on reward or punishment depend on the baseline levels of dopamine in a person’s brain. To test this, one hundred young healthy adults received (in different sessions) methylphenidate, sulpiride (a medication used to treat symptoms of schizophrenia that acts more selectively on dopamine receptors), or a placebo, and were later scanned with functional magnetic resonance imaging (fMRI) during a reward/punishment reversal learning task. In this task, participants learned to predict whether a picture (of a face or a landscape) that is selected by the computer is followed by reward or punishment. A reward outcome consisted of a green smiley and a + €100 sign. A punishment consisted of a red sad smiley and a – €100 sign. Whether the face or the landscape was associated with reward or punishment changed frequently in the task, so to perform well people had to continue to pay attention and flexibly update their behaviour based on prediction errors. 
 
The researchers observed that the degree to which both methylphenidate and sulpiride improved reward compared with punishment learning depends on baseline dopamine synthesis capacity. These learning effects were also were accompanied by increased activity in the striatum, a dopamine-rich region deep inside the brain, and also by increased specificity of the activity in regions of the cortex near the back of the brain that are specialised for processing faces and landscapes.
 
Their findings provide strong support for two hypotheses related to methylphenidate: First, that dopamine enhances task-relevant cortical signals by acting on the striatum. Second, that differences between individuals in dopamine synthesis capacity in the striatum explain the variability in the drug’s cognitive effects.

Source: Human Brain Project

Categories : Medical Research & TechnologyTags :

Sleeping with Weighted Blankets Increases Melatonin

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Sleeping woman
Photo by Cottonbro on Pexels

A small study has shown that young adults sleeping using weighted blankets had increased levels of the hormone melatonin, which increases in response to darkness, and which some research suggests promotes sleep. The findings are published in the Journal of Sleep Research.

Weighted blankets have been suggested to ease insomnia in humans in previous research but underlying mechanisms are not fully understood. To address this, Uppsala University researchers recruited 26 young men and women to examine if the bedtime use of a weighted blanket increases the production of sleep-promoting and anti-stress hormones like melatonin and oxytocin. They also investigated whether the bedtime use of a weighted blanket (12% of participants’ body weight) reduced the activity of stress systems in the body. Saliva samples were collected from participants while they were covered with either a weighted or a light blanket to measure melatonin, oxytocin, cortisol, and sympathetic nervous system activity.

“Using a weighted blanket increased melatonin concentrations in saliva by about 30%. However, no differences in oxytocin, cortisol, and the activity of the sympathetic nervous system were observed between the weighted and light blanket conditions,” reported Elisa Meth, first author and PhD student.

“Our study may offer a mechanism explaining why weighted blankets may exert some therapeutic benefits, such as improved sleep. However, our findings rely on a small sample and investigated only the acute effects of a weighted blanket. Thus, larger trials are needed, including an investigation of whether the observed effects of a weighted blanket on melatonin are sustained over longer periods,” said senior author Christian Benedict, Associate Professor at Uppsala University.

Source: Uppsala University

Categories : UncategorizedTags :

Treatment for Resolving C. Diff Infection ‘So Effective’ that Trial Discontinued

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Clostridioides difficile. Source: CDC

In a clinical trial, researchers found that, after a course of vancomycin, faecal microbiota transplantation (FMT) resolved Clostridioides difficile infections significantly more effectively than standard care alone. The treatment was so effective that further participant recruitment was halted. The findings were published in The Lancet Gastroenterology and Hepatology.

The results of the randomised, double-blind, placebo-controlled trial are extremely encouraging, said Simon Mark Dahl Baunwall, a PhD student at the Department of Clinical Medicine and a doctor at Aarhus University Hospital.

“Our new study shows that we can effectively cure the infection through the early use of faecal microbiota transplantation (FMT) after completing the standard treatment, to prevent relapses,” he said.

Few treatment options are available for the urgent threat of C. diff infections. Microbiota restoration with faecal microbiota transplantation is an effective treatment option for patients with multiple recurring episodes of C. diff. The researchers compared the efficacy and safety of faecal microbiota transplantation compared with placebo after vancomycin for first or second C. diff infection.

At a Danish hospital, 42 eligible patients with first or second C. difficile infection were randomly assigned to either faecal microbiota transplantation or placebo administered on day 1 and between day 3 and 7, after they had received 125mg oral vancomycin four times daily for 10 days. The primary endpoint was resolution of C difficile-associated diarrhoea (CDAD) eight weeks after treatment, with patients followed for eight weeks or until recurrence.

Due to the efficacy The primary outcome and safety outcomes were analysed in the intention-to-treat population, which included all randomly assigned patients.

Findings

The trial was stopped after the interim analysis done on April 7, 2022 for ethical reasons because the placebo group had a much lower rate of resolution at week 8 (33%) than the treatment group (90%). The absolute risk reduction was 57%.

“In rare cases, it can happen that you discover that the treatment you are investigating is so effective that it is ethically indefensible to continue,” said Baunwall.

“Our study is one example, in that the new FMT treatment is so much better than the standard treatment with antibiotics that it would be unethical to continue, because the patients in the control group would risk not receiving the FMT treatment.”

Overall, 204 adverse events occurred, with one or more adverse events being reported in 20 of 21 patients in the FMT group and all 21 patients in the placebo group, with the most common being diarrhoea and abdominal pain.

Interpretation

The study authors concluded that FMT in patients with first or second C. diff infection, is highly effective and superior to the standard of care vancomycin alone in achieving sustained resolution from C. diff.

Source: Aarhus University