Brain imaging reveals signs of childhood trauma
People who experience trauma may develop dissociative symptoms, such as amnesia and feeling numb, to help them cope. Over time, these coping mechanisms can negatively affect their ability to function in relationships and day-to-day life. A team of investigators at McLean Hospital in Belmont, Mass., has used brain imaging analyses to identify changes in functional connections between brain regions associated with these trauma-triggered dissociative symptoms. To reveal these changes, the team applied machine learning to functional magnetic resonance imaging tests of 65 women with histories of childhood abuse and ongoing post-traumatic stress disorder (PTSD). The approach, developed by Mewling Li, of Actinulae A. Martinod Center for Biomedical Imaging and a lead author of the study, showed a correlation between measurements in different brain regions, in particular the default mode and frontoparietal control networks, and the women’s dissociative symptoms. Historically, dissociative symptoms and disorders often have been doubted, leading to stigmatization and underdiagnosis, the researchers said. As a result, victims of childhood trauma who continue to suffer from these symptoms often lack access to effective mental health interventions. This study could help to address this issue by showing that dissociative symptoms in the brain can be objectively measured. “Furthermore, between-network brain connectivity may provide an unbiased example of symptom severity, paving the way for more objective, clinically useful biomarkers of dissociation and advancing our understanding of its neural mechanisms,” the authors wrote. The study was published online Sept. 25, 2020, in The American Journal of Psychiatry.
Buyer beware for SARS-CoV-2 antibody detection
Researchers at King’s College London and the Guy’s and St. Thomas’ NHS Foundation Trust have taken a close look at 10 commercially available SARS-CoV-2 antibody detection kits and reported on strengths and weaknesses alike. The team tested 110 samples of COVID-19 patients and 50 pre-pandemic samples with all 10 kits and compared the results to those from a highly sensitive assay they developed themselves. They looked at antibody assays that utilized three different technologies, namely, “one chemiluminescence-based platform, two ELISAs and seven colloidal gold lateral flow immunoassays (LFIAs).” The assays showed a range of sensitivities and specificities, but in general performed better on samples that had been taken longer after infection. The team did, somewhat worryingly, identify some “clear outlying samples that were negative in all tests, but were later shown to be from individuals with mildest disease presentation.” Nevertheless, they also noted that “some of the best-performing tests were rapid lateral flow immunoassays, which are affordable, quick and easy to use, and if they are deployed appropriately could have considerable utility in healthcare settings.” They reported their results in the Sept. 24, 2020, issue of Plos Pathogens.
Tumor-associated cell cluster signal cancer alert
A multicenter, international, collaborative study led by Datary Cancer Genetics Ltd. has demonstrated that it is possible to identify healthy individuals who are at higher risk of cancer based on a simple blood draw. Their work, published online Sept. 21, 2020, in Cancer Prevention Research, focused on the detection of detectable circulating ensembles of tumor associated cells (C-ETACs) in blood. It showed that seemingly healthy middle-aged men and women with detectable clusters of C-ETACs in blood samples have a 230-fold increase in one-year risk of cancer diagnosis, compared with people with undetectable clusters. To test the approach, the team screened more than 10,000 asymptomatic adults for the presence of C-ETACs and followed them for one year. Simultaneously, they analyzed blood from more than 4,000 cancer patients with various solid organ tumors. The results showed that C-ETACs were present in more than 90% of cancer patients, but in less than 5% of normal individuals with no cancer diagnosis or symptoms. Over the one-year follow-up, however, 3.475% of C-ETAC-positive individuals – those with detectable clusters in the blood – were diagnosed with cancer, compared with 0.015% of C-ETAC-negative individuals. The study could lead to earlier detection of cancer and better risk stratification, both of which remain challenges today. “We conclude that detection of C-ETACs can identify patients at risk of cancer and can be reliably used to stratify asymptomatic individuals with an elevated 1-year risk of cancer,” the researchers wrote. The C-ETAC detection technology and test were developed by Data Cancer Genetics, a Nashik, India-based cancer research company. The test’s accuracy is 95.6% and covers more than 20 cancers, including breast, lung, pancreatic, colon and prostate.