Surface wave elastography is a reliable method to correlate muscle elasticity, torque, and electromyography activity level

Abstract The shear elastic modulus is one of the most important parameters to characterize the mechanical behavior of soft tissues. In biomechanics, ultrasound elastography is the gold standard for measuring and mapping it locally in skeletal muscle in vivo. However, their applications are limited to the laboratory or clinic. Thus, low‐frequency elastography methods have recently emerged as a novel alternative to ultrasound elastography. Avoiding the use of high frequencies, these methods allow obtaining a mean value of bulk shear elasticity. However, they are frequently susceptible to diffraction, guided waves, and near field effects, which introduces biases in the estimates. The goal of this work is to test the performance of the non‐ultrasound surface wave elastography (NU‐SWE), which is portable and is based on new algorithms designed to correct the incidence of such effects. Thus, we show its first application to muscle biomechanics. We performed two experiments to assess the relationships of muscle shear elasticity versus joint torque (experiment 1) and the electromyographic activity level (experiment 2). Our results were comparable regarding previous works using the reference ultrasonic methods. Thus, the NU‐SWE showed its potentiality to get wide the biomechanical applications of elastography in many areas of health and sports sciences

Protein versus DNA as a marker for peripheral blood mononuclear cell counting

Quantitative analysis of intracellular analytes requires an accurate and precise assay not only for the quantitation of the analytes, but also for the quantitation of the number of cells in which they were determined. In this technical note we compare protein and DNA as markers for the number of peripheral blood mononuclear cells (PBMCs) isolated from whole blood. The protein content of samples was highly influenced by red blood cell contamination and was, therefore, a less suitable marker. The DNA-based method was unaffected by red blood cell contamination and was finally validated over a range from 10 × 106 to 300 × 106 PBMCs/mL

Short- and long-term follow-up after fecal microbiota transplantation as treatment for recurrent Clostridioides difficile infection in patients with inflammatory bowel disease

Background: Patients with inflammatory bowel disease (IBD) are at an increased risk of developing Clostridioides difficile infection (CDI). Treatment of CDI in patients with IBD is challenging due to higher failure rates and concomitant IBD activity. Objectives: We performed a multicentre cohort study in patients with IBD who received fecal microbiota transplantation (FMT) for recurrent CDI (rCDI), to further investigate factors that influence the clinical outcome and course of both rCDI and IBD. Design: This is a multicentre cohort study conducted in five European FMT centres. Methods: Adult IBD patients treated with FMT for rCDI were studied. Cure was defined as clinical resolution of diarrhoea or diarrhoea with a negative C. difficile test. The definition of an IBD flare was record based. Long-term follow-up data were collected including new episodes of CDI, IBD flares, infections, hospital admissions, and death. Results  In total, 113 IBD patients underwent FMT because of rCDI. Mean age of the patients was 48 years; 64% had ulcerative colitis. Concomitant rCDI was associated with an IBD flare in 54%, of whom 63% had received IBD remission-induction therapy prior to FMT. All FMT procedures were preceded by vancomycin treatment, 40% of patients received FMT via colonoscopy. CDI cure rate was 71%. Long-term follow-up data were available in 90 patients with a median follow-up of 784 days (402-1251). IBD activity decreased in 39% of patients who had active IBD at baseline, whereas an IBD flare occurred in only 5%. During follow-up of up to 2 years, 27% of the patients had infections, 39% were hospitalized, 5% underwent colectomy, and 10% died (median age of these latter patients: 72 years). Conclusion: FMT for rCDI in IBD patients is safe and effective, and IBD exacerbation after FMT is infrequent. Further studies should investigate the effects on IBD course following FMT.Cellular mechanisms in basic and clinical gastroenterology and hepatolog

High-Throughput Analysis of Promoter Occupancy Reveals New Targets for Arx, a Gene Mutated in Mental Retardation and Interneuronopathies

Genetic investigations of X-linked intellectual disabilities have implicated the ARX (Aristaless-related homeobox) gene in a wide spectrum of disorders extending from phenotypes characterised by severe neuronal migration defects such as lissencephaly, to mild or moderate forms of mental retardation without apparent brain abnormalities but with associated features of dystonia and epilepsy. Analysis of Arx spatio-temporal localisation profile in mouse revealed expression in telencephalic structures, mainly restricted to populations of GABAergic neurons at all stages of development. Furthermore, studies of the effects of ARX loss of function in humans and animal models revealed varying defects, suggesting multiple roles of this gene during brain development. However, to date, little is known about how ARX functions as a transcription factor and the nature of its targets. To better understand its role, we combined chromatin immunoprecipitation and mRNA expression with microarray analysis and identified a total of 1006 gene promoters bound by Arx in transfected neuroblastoma (N2a) cells and in mouse embryonic brain. Approximately 24% of Arx-bound genes were found to show expression changes following Arx overexpression or knock-down. Several of the Arx target genes we identified are known to be important for a variety of functions in brain development and some of them suggest new functions for Arx. Overall, these results identified multiple new candidate targets for Arx and should help to better understand the pathophysiological mechanisms of intellectual disability and epilepsy associated with ARX mutations

Vaccine breakthrough hypoxemic COVID-19 pneumonia in patients with auto-Abs neutralizing type I IFNs

Life-threatening `breakthrough' cases of critical COVID-19 are attributed to poor or waning antibody response to the SARS- CoV-2 vaccine in individuals already at risk. Pre-existing autoantibodies (auto-Abs) neutralizing type I IFNs underlie at least 15% of critical COVID-19 pneumonia cases in unvaccinated individuals; however, their contribution to hypoxemic breakthrough cases in vaccinated people remains unknown. Here, we studied a cohort of 48 individuals ( age 20-86 years) who received 2 doses of an mRNA vaccine and developed a breakthrough infection with hypoxemic COVID-19 pneumonia 2 weeks to 4 months later. Antibody levels to the vaccine, neutralization of the virus, and auto- Abs to type I IFNs were measured in the plasma. Forty-two individuals had no known deficiency of B cell immunity and a normal antibody response to the vaccine. Among them, ten (24%) had auto-Abs neutralizing type I IFNs (aged 43-86 years). Eight of these ten patients had auto-Abs neutralizing both IFN-a2 and IFN-., while two neutralized IFN-omega only. No patient neutralized IFN-ss. Seven neutralized 10 ng/mL of type I IFNs, and three 100 pg/mL only. Seven patients neutralized SARS-CoV-2 D614G and the Delta variant (B.1.617.2) efficiently, while one patient neutralized Delta slightly less efficiently. Two of the three patients neutralizing only 100 pg/mL of type I IFNs neutralized both D61G and Delta less efficiently. Despite two mRNA vaccine inoculations and the presence of circulating antibodies capable of neutralizing SARS-CoV-2, auto-Abs neutralizing type I IFNs may underlie a significant proportion of hypoxemic COVID-19 pneumonia cases, highlighting the importance of this particularly vulnerable population