Baseline colitogenicity and acute perturbations of gut microbiota in immunotherapy-related colitis.

Immunotherapy-related colitis (irC) frequently emerges as an immune-related adverse event during immune checkpoint inhibitor therapy and is presumably influenced by the gut microbiota. We longitudinally studied microbiomes from 38 ICI-treated cancer patients. We compared 13 ICI-treated subjects who developed irC against 25 ICI-treated subjects who remained irC-free, along with a validation cohort.

Gut microbiota strain richness is species specific and affects engraftment.

Despite the fundamental role of bacterial strain variation in gut microbiota function, the number of unique strains of a species that can stably colonize the human intestine is still unknown for almost all species. Here we determine the strain richness (SR) of common gut species using thousands of sequenced bacterial isolates with paired metagenomes. We show that SR varies across species, is transferable by faecal microbiota transplantation, and is uniquely low in the gut compared with soil and lake environments.

Immunoglobulin A antibody composition is sculpted to bind the self gut microbiome.

Despite being the most abundantly secreted immunoglobulin isotype, the pattern of reactivity of immunoglobulin A (IgA) antibodies toward each individual's own gut commensal bacteria still remains elusive. By colonizing germ-free mice with defined commensal bacteria, we found that the binding specificity of bulk fecal and serum IgA toward resident gut bacteria resolves well at the species level and has modest strain-level specificity. IgA hybridomas generated from lamina propria B cells of gnotobiotic mice showed that most IgA clones recognized a single bacterial species, whereas a small portion displayed cross-reactivity.

Precise quantification of bacterial strains after fecal microbiota transplantation delineates long-term engraftment and explains outcomes.

Fecal microbiota transplantation (FMT) has been successfully applied to treat recurrent Clostridium difficile infection in humans, but a precise method to measure which bacterial strains stably engraft in recipients and evaluate their association with clinical outcomes is lacking. We assembled a collection of >1,000 different bacterial strains that were cultured from the fecal samples of 22 FMT donors and recipients. Using our strain collection combined with metagenomic sequencing data from the same samples, we developed a statistical approach named Strainer for the detection and tracking of bacterial strains from metagenomic sequencing data.

Limited intestinal inflammation despite diarrhea, fecal viral RNA and SARS-CoV-2-specific IgA in patients with acute COVID-19.

Gastrointestinal symptoms are common in COVID-19 patients but the nature of the gut immune response to SARS-CoV-2 remains poorly characterized, partly due to the difficulty of obtaining biopsy specimens from infected individuals. In lieu of tissue samples, we measured cytokines, inflammatory markers, viral RNA, microbiome composition, and antibody responses in stool samples from a cohort of 44 hospitalized COVID-19 patients. SARS-CoV-2 RNA was detected in stool of 41% of patients and more frequently in patients with diarrhea.

Epigenomic regulation of human T-cell leukemia virus by chromatin-insulator CTCF.

Human T-cell leukemia virus type 1 (HTLV-1) is a retrovirus that causes an aggressive T-cell malignancy and a variety of inflammatory conditions. The integrated provirus includes a single binding site for the epigenomic insulator, CCCTC-binding protein (CTCF), but its function remains unclear. In the current study, a mutant virus was examined that eliminates the CTCF-binding site.

Intestinal Host Response to SARS-CoV-2 Infection and COVID-19 Outcomes in Patients With Gastrointestinal Symptoms.

Background & Aims: Given that gastrointestinal (GI) symptoms are a prominent extrapulmonary manifestation of COVID-19, we investigated intestinal infection with SARS-CoV-2, its effect on pathogenesis, and clinical significance.

Methods: Human intestinal biopsy tissues were obtained from patients with COVID-19 (n = 19) and uninfected control individuals (n = 10) for microscopic examination, cytometry by time of flight analyses, and RNA sequencing. Additionally, disease severity and mortality were examined in patients with and without GI symptoms in 2 large, independent cohorts of hospitalized patients in the United States (N = 634) and Europe (N = 287) using multivariate logistic regressions.

Gastrointestinal involvement attenuates COVID-19 severity and mortality.

Unlabelled: Given that gastrointestinal (GI) symptoms are a prominent extrapulmonary manifestation of coronavirus disease 2019 (COVID-19), we investigated intestinal infection with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and its effect on disease pathogenesis. SARS-CoV-2 was detected in small intestinal enterocytes by immunofluorescence staining or electron microscopy, in 13 of 15 patients studied. High dimensional analyses of GI tissues revealed low levels of inflammation in general, including active downregulation of key inflammatory genes such as and and reduced frequencies of proinflammatory dendritic cell subsets.

Limited intestinal inflammation despite diarrhea, fecal viral RNA and SARS-CoV-2-specific IgA in patients with acute COVID-19.

We sought to characterize the role of the gastrointestinal immune system in the pathogenesis of the inflammatory response associated with COVID-19. We measured cytokines, inflammatory markers, viral RNA, microbiome composition and antibody responses in stool from a cohort of 44 hospitalized COVID-19 patients. SARS-CoV-2 RNA was detected in stool of 41% of patients and more frequently in patients with diarrhea.

Inhibition of exendin-4-induced steatosis by protein kinase A in cultured HepG2 human hepatoma cells.

Nonalcoholic fatty liver is characterized by the abnormal accumulation of triglycerides within hepatocytes, resulting in a steatotic liver. Glucagon-like peptide 1 and its analog exendin-4 can ameliorate certain aspects of this syndrome by inducing weight loss and reducing hepatic triglyceride accumulation, but it is unclear whether these effects result from the effects of glucagon-like peptide 1 on the pancreas, or from direct action on the liver. This study investigated the direct action and putative cellular mechanism of exendin-4 on steatotic hepatocytes in culture.

Melatonin premedication versus placebo in wisdom teeth extraction: a randomised controlled trial.

Introduction: Pain after wisdom teeth surgery can be moderate in severity and is compounded by preoperative anxiety in young patients. We studied the effect of melatonin premedication on postoperative pain and preoperative anxiety in patients undergoing wisdom teeth extractions.

Methods: This randomised controlled trial recruited 76 patients at Khoo Teck Puat Hospital who were American Society of Anesthesiologists physical status I and II, aged 21 to 65 and scheduled to undergo elective extraction of all four wisdom teeth under general anaesthesia.

High STOP-BANG questionnaire scores predict intraoperative and early postoperative adverse events.

Introduction: Obstructive sleep apnoea (OSA) is the most common sleep-related breathing disorder associated with multisystemic organ involvement. The STOP-BANG questionnaire is a concise, validated questionnaire that is used to screen for OSA. This study aimed to establish the use of the STOP-BANG questionnaire for perioperative patient risk stratification.

Factors associated with falls among community-dwelling older people in Taiwan.

Introduction: Falls are common among older people. Previous studies have shown that falls were multifactorial. However, data regarding community-dwelling Chinese population are minimal.

Differential tissue and ligand-dependent signaling of GPR109A receptor: implications for anti-atherosclerotic therapeutic potential.

Until recently, the anti-atherosclerotic effects of niacin were attributed primarily to its lipid modification properties mediated by adipocyte G-protein coupled receptor GPR109A, though recent studies have raised significant doubts about this mechanism. In fact, in rodents it has recently been demonstrated that niacin inhibits progression of atherosclerosis through actions on immune cells, particularly via macrophage-expressed GPR109A, independent of lipid-modifying properties. Here, we studied GPR109A signal transduction in human Langerhans cells, macrophages and adipocytes.

Comparison of results from novice and trained personnel using the Macintosh laryngoscope, Pentax AWS®, C-MAC™ and Bonfils intubation fibrescope: a manikin study.

Introduction: Indirect laryngoscopes offer improved laryngeal view and higher success rates of intubation, particularly for difficult airways. We hypothesised that: (a) the time required for intubation, overall success rates and ease of intubation with indirect laryngoscopes would be better than with the Macintosh laryngoscope; and (b) novices may achieve higher success rates and intubate faster using indirect laryngoscopes.

Methods: In a cross-sectional observational study, 13 novices and 13 skilled anaesthetists were recruited.

Loss of T cell progenitor checkpoint control underlies leukemia initiation in Rag1-deficient nonobese diabetic mice.

NOD mice exhibit major defects in the earliest stages of T cell development in the thymus. Genome-wide genetic and transcriptome analyses were used to investigate the origins and consequences of an early T cell developmental checkpoint breakthrough in Rag1-deficient NOD mice. Quantitative trait locus analysis mapped the presence of checkpoint breakthrough cells to several known NOD diabetes susceptibility regions, particularly insulin-dependent diabetes susceptibility genes (Idd)9/11 on chromosome 4, suggesting common genetic origins for T cell defects affecting this trait and autoimmunity.

Inhibition of Mas G-protein signaling improves coronary blood flow, reduces myocardial infarct size, and provides long-term cardioprotection.

The Mas receptor is a class I G-protein-coupled receptor that is expressed in brain, testis, heart, and kidney. The intracellular signaling pathways activated downstream of Mas are still largely unknown. In the present study, we examined the expression pattern and signaling of Mas in the heart and assessed the participation of Mas in cardiac ischemia-reperfusion injury.

Sequence polymorphisms provide a common consensus sequence for GPR41 and GPR42.

GPR41 and GPR42 are two closely related genes that are part of a cluster of four adjacent G protein-coupled receptors (GPCRs) (GPR40, 41, 42, and 43) localized on human chromosome 19. There are only six nucleotide and amino acid differences between GPR41 and GPR42. High sequence homology between these two genes suggests that they are the result of a recent duplication event.

The role of the GPR91 ligand succinate in hematopoiesis.

Regulation of cellular metabolism by the citric acid cycle occurs in the mitochondria. However, the citric acid cycle intermediate succinate was shown recently to be a ligand for the G-protein-coupled receptor GPR91. Here, we describe a role for succinate and its receptor in the stimulation of hematopoietic progenitor cell (HPC) growth.

Myocardial expression, signaling, and function of GPR22: a protective role for an orphan G protein-coupled receptor.

G protein-coupled receptors (GPCRs) play an essential role in the regulation of cardiovascular function. Therapeutic modulation of GPCRs has proven to be beneficial in the treatment of human heart disease. Myocardial "orphan" GPCRs, for which the natural ligand is unknown, represent potential novel therapeutic targets for the treatment of heart disease.

(D)-beta-Hydroxybutyrate inhibits adipocyte lipolysis via the nicotinic acid receptor PUMA-G.

As a treatment for dyslipidemia, oral doses of 1-3 grams of nicotinic acid per day lower serum triglycerides, raise high density lipoprotein cholesterol, and reduce mortality from coronary heart disease (Tavintharan, S., and Kashyap, M. L.