Colonic Anastomotic Leak Model in Swine.

INTRODUCTION: Anastomotic leaks (ALs) are serious postoperative complications. Current experimental studies designed to investigate leaks are based on acute intraoperative dehiscence of the anastomosis. Clinically, however, AL usually happens later in the postoperative course. Presented here is a clinically relevant colonic AL model in swine. METHODS: Seventeen Yorkshire pigs were divided into 2 groups: the control group (n = 6) and the experimental group (n = 11). An enterotomy was performed on the descending colon and an end-to-end handsewn anastomosis was created in the groups. The proximal and distal ends of the suture were exteriorized and tied to a plastic tube. Subsequently, the suture was cut and pulled to induce breakdown of the anastomosis in the experimental group 3-4 h postoperatively. Study endpoints included behavioral changes, clinical assessment, laboratory indicators, and macroscopic indicators of leakage. RESULTS: Leaks were successfully created in 8/11 of the experimental group animals and confirmed through exploratory relaparotomy. Seven of the experimental pigs showed complete anastomotic breakdown and one showed partial rupture. Fecal peritonitis and enteric spillage were observed macroscopically within the abdomen of the experimental pigs, confirming the presence of a leak. The remaining (3/11) experimental pigs did not experience those findings due to either a tamponade/containment by the abdominal wall or surrounding organs. Statistical significance (p < 0.05) was achieved between the experimental and control cohorts for laboratory and clinical indicators including fever, leukocytosis, and decreased blood potassium. CONCLUSION: This animal model generated postoperative induced leak in approximately three-quarters (8/11) of experimental pigs, allowing control over the time of leak onset to simulate clinical settings.

Exploration of O-GlcNAc transferase glycosylation sites reveals a target sequence compositional bias.

O-GlcNAc transferase (OGT) is an essential glycosylating enzyme that catalyzes the addition of N-acetylglucosamine to serine or threonine residues of nuclear and cytoplasmic proteins. The enzyme glycosylates a broad range of peptide sequences and the prediction of glycosylation sites has proven challenging. The lack of an experimentally verified set of polypeptide sequences that are not glycosylated by OGT has made prediction of legitimate glycosylation sites more difficult. Here, we tested a number of intrinsically disordered protein regions as substrates of OGT to establish a set of sequences that are not glycosylated by OGT. The negative data set suggests an amino acid compositional bias for OGT targets. This compositional bias was validated by modifying the amino acid composition of the protein fused in sarcoma (FUS) to enhance glycosylation. NMR experiments demonstrate that the tetratricopeptide repeat region of OGT can bind FUS and that glycosylation-promoting mutations enhance binding. These results provide evidence that the tetratricopeptide repeat region recognizes disordered segments of substrates with particular compositions to promote glycosylation, providing insight into the broad specificity of OGT.

Mental Health Consequences of the COVID-19 Pandemic Among Ontario's Youth: A Cross-Sectional Study.

The coronavirus disease 2019 (COVID-19) pandemic has had a significant impact on the mental health and wellbeing of Ontario's youth. Our study investigated the psychological impacts of COVID-19 on the pediatric population of Ontario, using a survey derived from the Revised Children's Anxiety and Depression Scale (RCADS) system to identify children who may benefit from seeking professional help. Our cross-sectional study examined the potential risk factors that contributed to worsening mental health and wellbeing in children, including changes in sleep patterns, appetite, and physical activity levels, as well as the diagnosis of a family member with COVID-19. Our study found that 24%, 9.4%, and 15.5% of participants exhibited symptoms of depression, anxiety, and obsessive-compulsive disorder (OCD), respectively, according to the RCADS system. Furthermore, there were significant associations between the presence of symptoms and the diagnosis of a family member with COVID-19 or a frontline worker in the family. This suggests a need to create interventions to support the families of frontline workers and those directly affected by a COVID-19 diagnosis.

Yoga for the Management of Attention-Deficit/Hyperactivity Disorder.

Yoga has been shown to play a role in reducing the symptoms associated with the inattentive and hyperactive-impulsive forms of attention-deficit/hyperactivity disorder (ADHD). The medical history and clinical findings for a nine-year-old patient presenting with difficulty paying attention and impulsive speech and actions at home and school are presented. After the diagnosis of combination type ADHD by assessment of DSM-5 criteria, both at home and school and through parent and teacher evaluations using National Institute for Children's Health Quality (NICHQ) Vanderbilt Assessment Scales, the patient initiated a yoga training regimen. Six months after initiating the yoga training regimen, follow-up parent and teacher questionnaires revealed improvement in both the inattentive and hyperactive-impulsive symptoms. Literature sourced from the PubMed database to explore the efficacy of yoga for ADHD was used to support the research hypothesis that a structured yoga training regimen improves the symptoms associated with the inattentive and hyperactive-impulsive forms of ADHD, and thus, yoga is recommended as a management technique for individuals with ADHD.

Non-cooperative 4E-BP2 folding with exchange between eIF4E-binding and binding-incompatible states tunes cap-dependent translation inhibition.

Phosphorylation of intrinsically disordered eIF4E binding proteins (4E-BPs) regulates cap-dependent translation by weakening their ability to compete with eIF4G for eIF4E binding within the translation initiation complex. We previously showed that phosphorylation of T37 and T46 in 4E-BP2 induces folding of a four-stranded beta-fold domain, partially sequestering the canonical eIF4E-binding helix. The C-terminal intrinsically disordered region (C-IDR), remaining disordered after phosphorylation, contains the secondary eIF4E-binding site and three other phospho-sites, whose mechanisms in inhibiting binding are not understood. Here we report that the domain is non-cooperatively folded, with exchange between beta strands and helical conformations. C-IDR phosphorylation shifts the conformational equilibrium, controlling access to eIF4E binding sites. The hairpin turns formed by pT37/pT46 are remarkably stable and function as transplantable units for phospho-regulation of stability. These results demonstrate how non-cooperative folding and conformational exchange leads to graded inhibition of 4E-BP2:eIF4E binding, shifting 4E-BP2 into an eIF4E binding-incompatible conformation and regulating translation initiation.