Gut inflammation and adaptive immunity amplify acetaminophen toxicity in bowel and liver.

BACKGROUND AND AIM: Prevention of liver failure arising from accidental or deliberate paracetamol (acetaminophen [APAP]) overdose remains a vexed health problem despite well-publicized guidelines for its early detection and treatment. It is recognized that the gut may aggravate liver pathology, via the gut-liver axis. The main aim of this study was to assess the role of the colon in APAP-induced liver toxicity. METHODS: Liver necrosis and colitis were studied following sublethal doses of APAP administered intraperitoneally to C57Bl/6 wild-type (WT) mice, as well as to C57Bl/6 Winnie mice, which develop a spontaneous colitis caused by a SNP in Muc2, and WT mice with acute DSS-induced colitis. Repeated APAP exposure was studied in WT and Rag1 ko mice that lack mature T and B lymphocytes. RESULTS: APAP overdose resulted in significant colonic injury in WT mice (P < 0.05), which resolved by 24 h. Underlying colitis was not associated with liver necrosis, but colitis exacerbated APAP-induced liver injury and extended APAP-colonic injury. Prior APAP exposure exacerbated both APAP-liver and APAP-colonic injury more so in WT than Rag1 ko mice. APAP impaired barrier function with increased intestinal permeability and associated bacterial translocation to the liver and spleen in mice with the Winnie phenotype. CONCLUSIONS: This study identifies novel roles for APAP in causing colitis, the amplification of APAP-liver toxicity where there is underlying colitis, and involvement of immune memory in APAP-toxicity. The latter could be key for decoding the poorly understood but important clinical entity of chronic APAP liver failure.

Epithelial TLR4 Signaling Activates DUOX2 to Induce Microbiota-Driven Tumorigenesis.

BACKGROUND & AIMS: Chronic colonic inflammation leads to dysplasia and cancer in patients with inflammatory bowel disease. We have described the critical role of innate immune signaling via Toll-like receptor 4 (TLR4) in the pathogenesis of dysplasia and cancer. In the current study, we interrogate the intersection of TLR4 signaling, epithelial redox activity, and the microbiota in colitis-associated neoplasia. METHODS: Inflammatory bowel disease and colorectal cancer data sets were analyzed for expression of TLR4, dual oxidase 2 (DUOX2), and NADPH oxidase 1 (NOX1). Epithelial production of hydrogen peroxide (H2O2) was analyzed in murine colonic epithelial cells and colonoid cultures. Colorectal cancer models were carried out in villin-TLR4 mice, carrying a constitutively active form of TLR4, their littermates, and villin-TLR4 mice backcrossed to DUOXA-knockout mice. The role of the TLR4-shaped microbiota in tumor development was tested in wild-type germ-free mice. RESULTS: Activation of epithelial TLR4 was associated with up-regulation of DUOX2 and NOX1 in inflammatory bowel disease and colorectal cancer. DUOX2 was exquisitely dependent on TLR4 signaling and mediated the production of epithelial H2O2. Epithelial H2O2 was significantly increased in villin-TLR4 mice; TLR4-dependent tumorigenesis required the presence of DUOX2 and a microbiota. Mucosa-associated microbiota transferred from villin-TLR4 mice to wild-type germ-free mice caused increased H2O2 production and tumorigenesis. CONCLUSIONS: Increased TLR4 signaling in colitis drives expression of DUOX2 and epithelial production of H2O2. The local milieu imprints the mucosal microbiota and imbues it with pathogenic properties demonstrated by enhanced epithelial reactive oxygen species and increased development of colitis-associated tumors. The inter-relationship between epithelial reactive oxygen species and tumor-promoting microbiota requires a 2-pronged strategy to reduce the risk of dysplasia in colitis patients.

Gadolinium: pharmacokinetics and toxicity in humans and laboratory animals following contrast agent administration.

Gadolinium-based contrast agents (GBCAs) have transformed magnetic resonance imaging (MRI) by facilitating the use of contrast-enhanced MRI to allow vital clinical diagnosis in a plethora of disease that would otherwise remain undetected. Although over 500 million doses have been administered worldwide, scientific research has documented the retention of gadolinium in tissues, long after exposure, and the discovery of a GBCA-associated disease termed nephrogenic systemic fibrosis, found in patients with impaired renal function. An understanding of the pharmacokinetics in humans and animals alike are pivotal to the understanding of the distribution and excretion of gadolinium and GBCAs, and ultimately their potential retention. This has been well studied in humans and more so in animals, and recently there has been a particular focus on potential toxicities associated with multiple GBCA administration. The purpose of this review is to highlight what is currently known in the literature regarding the pharmacokinetics of gadolinium in humans and animals, and any toxicity associated with GBCA use.

Adhesion to E-selectin primes macrophages for activation through AKT and mTOR.

The endothelial adhesion protein E-selectin/CD62E is not required for leukocyte homing, unlike closely related family member P-selectin/CD62P. As transmigration through the endothelium is one of the first steps in generating a local immune response, we hypothesized that E-selectin may play additional roles in the early stages of immune activation. We found contact with E-selectin, but not P-selectin or vascular cell adhesion molecule 1 (CD106), induced phosphorylation of protein kinase B (AKT) and nuclear factor-κB in mouse bone marrow-derived macrophages (BMDMs) in vitro. This occurred within 15 min of E-selectin contact and was dependent on phosphatidylinositol-3 kinase activity. Binding to E-selectin activated downstream proteins including mammalian target of rapamycin, p70 ribosomal protein S6 kinase and eukaryotic translation initiation factor 4E-binding protein 1. Functionally, adhesion to E-selectin induced upregulation of CD86 expression and CCL2 secretion. We next asked whether contact with E-selectin impacts further BMDM stimulation. We found enhanced secretion of both interleukin (IL)-10 and CCL2, but not tumor necrosis factor or IL-6 in response to lipopolysaccharide (LPS) stimulation after adhesion to E-selectin. Importantly, adhesion to E-selectin did not polarize BMDMs to one type of response but enhanced both arginase activity and nitric oxide production following IL-4 or LPS stimulation, respectively. In cultured human monocytes, adhesion to E-selectin similarly induced phosphorylation of AKT. Finally, when E-selectin was blocked in vivo in mice, thioglycollate-elicited macrophages showed reduced CD86 expression, validating our in vitro studies. Our results imply functions for E-selectin beyond homing and suggest that E-selectin plays an early role in priming and amplifying innate immune responses.

Intestinal exposure to PCB 153 induces inflammation via the ATM/NEMO pathway.

BACKGROUND: Polychlorinated biphenyls (PCBs) are persistent organic pollutants that adversely affect human health. PCBs bio-accumulate in organisms important for human consumption. PCBs accumulation in the body leads to activation of the transcription factor NF-κB, a major driver of inflammation. Despite dietary exposure being one of the main routes of exposure to PCBs, the gut has been widely ignored when studying the effects of PCBs. OBJECTIVES: We investigated the effects of PCB 153 on the intestine and addressed whether PCB 153 affected intestinal permeability or inflammation and the mechanism by which this occurred. METHODS: Mice were orally exposed to PCB 153 and gut permeability was assessed. Intestinal epithelial cells (IECs) were collected and evaluated for evidence of genotoxicity and inflammation. A human IEC line (SW480) was used to examine the direct effects of PCB 153 on epithelial function. NF-кB activation was measured using a reporter assay, DNA damage was assessed, and cytokine expression was ascertained with real-time PCR. RESULTS: Mice orally exposed to PCB 153 had an increase in intestinal permeability and inflammatory cytokine expression in their IECs; inhibition of NF-кB ameliorated both these effects. This inflammation was associated with genotoxic damage and NF-кB activation. Exposure of SW480 cells to PCB 153 led to similar effects as seen in vivo. We found that activation of the ATM/NEMO pathway by genotoxic stress was upstream of NF-kB activation. CONCLUSIONS: These results demonstrate that oral exposure to PCB 153 is genotoxic to IECs and induces downstream inflammation and barrier dysfunction in the intestinal epithelium.

Validity of auditory perceptual assessment of velopharyngeal function and dysfunction - the VPC-Sum and the VPC-Rate.

Overall weighted or composite variables for perceptual auditory estimation of velopharyngeal closure or competence have been used in several studies for evaluation of velopharyngeal function during speech. The aim of the present study was to investigate the validity of a composite score (VPC-Sum) and of auditory perceptual ratings of velopharyngeal competence (VPC-Rate). Available VPC-Sum scores and judgments of associated variables (hypernasality, audible nasal air leakage, weak pressure consonants, and non-oral articulation) from 391 5-year olds with repaired cleft palate (the Scandcleft project) were used to investigate content validity, and 339 of these were compared with an overall judgment of velopharyngeal competence (VPC-Rate) on the same patients by the same listeners. Significant positive correlations were found between the VPC-Sum and each of the associated variables (Cronbachs alpha 0.55-0.87, P < 0.001), and a moderately significant positive correlation between VPC-Sum and VPC-Rate (Rho 0.698, P < 0.01). The latter classified cases well when VPC-Sum was dichotomized with 67% predicted velopharyngeal competence and 90% velopharyngeal incompetence. The validity of the VPC-Sum was good and the VPC-Rate a good predictor, suggesting possible use of both measures depending on the objective.

Intestinal Epithelial Toll-Like Receptor 4 Signaling Affects Epithelial Function and Colonic Microbiota and Promotes a Risk for Transmissible Colitis.

Evidence obtained from gene knockout studies supports the role of Toll-like receptor 4 (TLR4) in intestinal inflammation and microbiota recognition. Increased epithelial TLR4 expression is observed in patients with inflammatory bowel disease. However, little is known of the effect of increased TLR4 signaling on intestinal homeostasis. Here, we examined the effect of increased TLR4 signaling on epithelial function and microbiota by using transgenic villin-TLR4 mice that overexpress TLR4 in the intestinal epithelium. Our results revealed that villin-TLR4 mice are characterized by increases in the density of mucosa-associated bacteria and bacterial translocation. Furthermore, increased epithelial TLR4 signaling was associated with an impaired epithelial barrier, altered expression of antimicrobial peptide genes, and altered epithelial cell differentiation. The composition of the colonic luminal and mucosa-associated microbiota differed between villin-TLR4 and wild-type (WT) littermates. Interestingly, WT mice cohoused with villin-TLR4 mice displayed greater susceptibility to acute colitis than singly housed WT mice did. The results of this study suggest that epithelial TLR4 expression shapes the microbiota and affects the functional properties of the epithelium. The changes in the microbiota induced by increased epithelial TLR4 signaling are transmissible and exacerbate dextran sodium sulfate-induced colitis. Together, our findings imply that host innate immune signaling can modulate intestinal bacteria and ultimately the host's susceptibility to colitis.

Cuprizone demyelination induces a unique inflammatory response in the subventricular zone.

BACKGROUND: Cuprizone leads to demyelination of the corpus callosum (CC) and activates progenitor cells in the adjacent subventricular zone (SVZ), a stem cell niche which contributes to remyelination. The healthy SVZ contains semi-activated microglia and constitutively expresses the pro-inflammatory molecule galectin-3 (Gal-3) suggesting the niche uniquely regulates inflammation. METHODS: We studied the inflammatory response to cuprizone in the SVZ and CC in Gal-3 knockout mice using immunohistochemistry and with the in vitro neurosphere assay. RESULTS: Cuprizone caused loss of myelin basic protein (MBP) immunofluorescence in the CC suggesting demyelination. Cuprizone increased the density of CD45+/Iba1+ microglial cells and also increased Gal-3 expression in the CC. Surprisingly, the number of Gal-3+ and CD45+ cells decreased in the SVZ after cuprizone, suggesting inflammation was selectively reduced therein. Inflammation can regulate SVZ proliferation and indeed the number of phosphohistone H3+ (PHi3+) cells decreased in the SVZ but increased in the CC in both genotypes after cuprizone treatment. BrdU+ SVZ cell numbers also decreased in the SVZ after cuprizone, and this effect was significantly greater at 3 weeks in Gal-3 (-/-) mice compared to WT, suggesting Gal-3 normally limits SVZ cell emigration following cuprizone treatment. CONCLUSIONS: This study reveals a uniquely regulated inflammatory response in the SVZ and shows that Gal-3 participates in remyelination in the cuprizone model. This contrasts with more severe models of demyelination which induce SVZ inflammation and suggests the extent of demyelination affects the SVZ neurogenic response.

Host-microbe interactions in the small bowel.

PURPOSE OF REVIEW: The intestine - home to a vast microbiome - balances its immune reactivity on a knife's edge. This review will summarize recent studies examining innate immune signals that shape the microbiota, and how pathogens can usurp protective responses to their advantage. RECENT FINDINGS: Innate signaling uses several pathways to maintain epithelial defense. Toll-like receptor signaling through myeloid differentiation factor 88 maintains segregation between bacteria and the epithelium through production of antimicrobial proteins, and inflammasome signaling mediates efficient goblet cell release of mucus containing granules. Conversely, negative regulators of Toll-like receptor signaling help maintain a healthy microbiota resistant to pathogen infection. Methods to evade immune elimination by pathogens associated with human infections and inflammatory bowel disease are described. Emerging evidence that pattern recognition receptors can differentiate between commensals and pathogens will be examined. SUMMARY: The balance of innate signaling in the intestine is crucial to homeostasis: too little and bacteria can directly contact the epithelium, too much depletes the protective microbiota, creating a niche for pathogens. Understanding the dynamic interaction between the immune system and the microbiota in a variety of infection and inflammation models will hopefully translate to new therapies.

The innate immune system and inflammatory bowel disease.

The innate immune system is a key factor in understanding the pathogenesis of inflammatory bowel disease (IBD) and in the hopes of improving its treatment. NOD2, a pattern recognition receptor, was one of the first major susceptibility genes identified in Crohn's disease (CD). This discovery has been followed by genome-wide association studies that have identified other genes involved in innate immune responses. Most notably, polymorphisms in the interleukin (IL)-23 receptor have also been linked to IBD - both CD and ulcerative colitis. At the core of the innate immune defects associated with IBD is a lack of generating a robust response to control invasive commensal or pathogenic bacteria. The defect sometimes lies in a failure of the epithelium to express antimicrobial peptides or in defective control of intracellular bacteria by phagocytic cells such as dendritic cells, macrophages, or neutrophils. The recent identification of innate lymphoid cells that express the IL-23 receptor and generate both proinflammatory and protective or regulatory responses to commensal or pathogenic bacteria provides another layer of complexity to the interplay of host protection and dysregulated inflammation. Although inhibition of tumor necrosis factor has been highly successful as a strategy in treating IBD, we must better understand the nuanced role of other innate cytokines before we may incorporate these in the treatment of IBD.

Does Improving Depression Symptoms in Young Adults With Inflammatory Bowel Disease Alter Their Microbiome?

BACKGROUND: Patients with inflammatory bowel diseases (IBDs) are more likely to have depression and anxiety symptoms compared with healthy individuals and those with other chronic illnesses. Previous studies have shown a link between the microbiome composition and depression symptoms; however, many antidepressant medications have antibacterial activity confounding cross-sectional studies of these populations. Therefore, we aimed to determine whether we could detect longitudinal changes in the microbiome of a subset of patients who participated in a previously published mindfulness-based cognitive therapy (MBCT) study to improve depression symptoms in adolescents and young adults with IBD. METHODS: Stool samples were collected at baseline and 8 weeks (n = 24 participants, 37 total samples, 13 paired samples). During this time, some participants achieved a 50% reduction in their depression symptoms either through MBCT or treatment as usual with their mental health team (responders). The microbiome composition and function of responders were compared with participants who did not improve their depression scores (nonresponders). Depression scores were determined using the depression, anxiety, and stress score (DASS-21), and metagenomic sequencing of stool samples was performed. RESULTS: No difference in alpha diversity was found between responders and nonresponders. Beta diversity measures were similarly unchanged. Clinical features including fecal calprotectin, C-reactive protein, and serum IL-6 levels were unchanged. CONCLUSIONS: In this small longitudinal study, we were not able to detect longitudinal changes in the microbiome associated with improvement in depression scores. Follow-up studies that are sufficiently powered to detect changes in the microbiome are required to confirm our results.

In a small cohort of young adults with inflammatory bowel disease and depression symptoms, we observed no significant longitudinal changes in their microbiome following improvement in their depression scores.

Striving for equity: exploring gender-inclusive medical leadership in India.

INTRODUCTION: There is a notable gap in studies examining the impact of gender within sociocultural norms in non-western professional settings, especially concerning the well-being of women physicians. METHODS: Using purposive sampling and thematic data analysis, we recorded interviews with 30 physicians in India during May-July 2023. Participants were aged 34 to 65 years, with experience ranging from five to 35 years, in various clinical (37%), surgical (30%), paraclinical (23%) and hospital administration (10%) roles, 97% were postgraduates and 53% were women. The research questions explored how leadership roles happened, managing key challenges, barriers and enablers, and practical interventions to support women into medical leadership positions. RESULTS: Findings revealed that the majority of interviewees believed gender-related barriers were obstructing women's progress and success in medical leadership roles in India. These barriers were identified within three overarching domains: (1) specialty, (2) organisational and (3) sociocultural. Interviewees commonly acknowledged the male-dominated landscape of medical leadership although some women stated that they did not perceive any barriers for women's advancement into leadership roles. Interestingly, some men surgeons held the perception that women might not be as effective in certain surgical disciplines, such as orthopaedics and neurosurgery. Some men physicians, however, considered women physicians in India to be highly effective multitaskers. CONCLUSION: We recommend structural reforms in medical education, leadership development, workplace systems and cultures, and improved implementation of equality, diversity and inclusion policies in the Indian context.

Preexisting tissue mechanical hypertension at adherens junctions disrupts apoptotic extrusion in epithelia.

Apical extrusion is a tissue-intrinsic process that allows epithelia to eliminate unfit or surplus cells. This is exemplified by the early extrusion of apoptotic cells, which is critical to maintain the epithelial barrier and prevent inflammation. Apoptotic extrusion is an active mechanical process, which involves mechanotransduction between apoptotic cells and their neighbors, as well as local changes in tissue mechanics. Here we report that the preexisting mechanical tension at adherens junctions (AJs) conditions the efficacy of apoptotic extrusion. Specifically, increasing baseline mechanical tension by overexpression of a phosphomimetic Myosin II regulatory light chain (MRLC) compromises apoptotic extrusion. This occurs when tension is increased in either the apoptotic cell or its surrounding epithelium. Further, we find that the proinflammatory cytokine, TNFα, stimulates Myosin II and increases baseline AJ tension to disrupt apical extrusion, causing apoptotic cells to be retained in monolayers. Importantly, reversal of mechanical tension with an inhibitory MRLC mutant or tropomyosin inhibitors is sufficient to restore apoptotic extrusion in TNFα-treated monolayers. Together, these findings demonstrate that baseline levels of tissue tension are important determinants of apoptotic extrusion, which can potentially be coopted by pathogenetic factors to disrupt the homeostatic response of epithelia to apoptosis.

Profiling UK injectable aesthetic practitioners: A national cohort analysis.

INTRODUCTION: The United Kingdom (UK) injectables market has been growing rapidly with a lack of robust regulation and to date, no information regarding the profile of practitioners has been published. AIM: We aim to provide a descriptive and qualitative analysis of the advertised practitioners in the United Kingdom. METHODS: We performed a systematic search using the internet search engine Google to perform a qualitative descriptive analysis of aesthetic practitioners in the UK. For each contiguous country in the UK: England, Scotland, and Wales, five searches were performed. The list of practitioners was then cross-referenced with professional regulatory bodies, with extraction of registration number, date of registration and presence or absence from the Specialist Register or General Practitioner Register. RESULTS: 3000 websites were visited and evaluated. 1224 independent clinics with 4405 practitioners were identified. 738 were identified as those in business support functions and the remaining 3667 practitioners were undertaking injectable practice. The profile of professions were doctors 32%, nurses 13%, dentists 24% and dental nurses 8%. Of the 1163 doctors identified 481 were on the specialist register (41%) and 219 were on the GP register (19%). 27 specialties were represented in this cohort analysis. Plastic Surgery formed the majority of those who were on the specialist register at 37%, followed by Dermatology at 18%. CONCLUSION: This paper is the first to describe the range of practitioners, their professional backgrounds and experience who perform non-surgical aesthetic interventions. The range of backgrounds may have an impact on the potential risks to patients and will be an important consideration in proposed legislation to introduce licensing to the industry.

Cosmetic business mechanics in London: A cross-sectional analysis and audit of ASA compliance.

INTRODUCTION: The proliferation of providers and practitioners of cosmetic botulinum toxin and dermal filler has profound public health implications. The Advertising Standards Authority (ASA) regulates the use of advertising materials in the United Kingdom and prohibits the promotion of prescription-only medicines. AIMS: We aim to perform a cross-sectional analysis of the practitioners in London, UK to evaluate the distribution of clinics within Greater London, prices advertised for interventions, and compliance with the ASA code. We also aim to identify whether there are any differences in cost of botulinum toxin or dermal filler between the boroughs. METHODS: Between December 2021 and January 2022, we performed a systematic search using the internet search engine Google. Five searches were performed (1) [london] botox, (2) [london] botulinum toxin, (3) [london] anti wrinkle injection, (4) [london] filler, (5) [london] dermal filler. One hundred websites per search string were systematically reviewed and those which met the inclusion/exclusion criteria of each search string were included and analyzed. Each clinic's product/service range compliance with the ASA/CAP code was assessed. Any reference to Botulinum Toxin or anti-wrinkle injections was noted and analyzed. Further analysis would look to calculate price per milliliter (mL) of botulinum toxin and dermal filler per borough and to calculate whether there were any statistical differences between the 32 different London boroughs. RESULTS: A total of 500 websites were visited and evaluated. After removal of duplicates, a total of 233 independent clinics was identified. A total of 206 out of the 233 clinics sampled (88%) were in direct infringement of the enforcement notice through advertising a prescription medicine. The overall average cost per mL of dermal filler was £330.89 and there was a statistically significant variance across London boroughs (p < 0.05). The overall average cost per mL of Botulinum Toxin was £284.45 and the variance across London boroughs was close to significant (p = 0.058). CONCLUSION: This paper demonstrates poor compliance with the ASA/CAP guidelines and further provides an insight into the industry mechanics associated with aesthetic injectables in a major UK city, identifying regional variance in price and clinic density. The advertising of prescription-only medication may pose a potential risk to patients and will be an important consideration in proposed legislation to introduce licensing to the industry.

The flutemetamol analogue cyano-flutemetamol detects myocardial AL and ATTR amyloid deposits: a post-mortem histofluorescence analysis.

BACKGROUND: [18F]flutemetamol is a PET radioligand used to image brain amyloid, but its detection of myocardial amyloid is not well-characterized. This histological study characterized binding of fluorescently labeled flutemetamol (cyano-flutemetamol) to amyloid deposits in myocardium. METHODS: Myocardial tissue was obtained post-mortem from 29 subjects with cardiac amyloidosis including transthyretin wild-type (ATTRwt), hereditary/variant transthyretin (ATTRv) and immunoglobulin light-chain (AL) types, and from 10 cardiac amyloid-free controls. Most subjects had antemortem electrocardiography, echocardiography, SPECT and cardiac MRI. Cyano-flutemetamol labeling patterns and integrated density values were evaluated relative to fluorescent derivatives of Congo red (X-34) and Pittsburgh compound-B (cyano-PiB). RESULTS: Cyano-flutemetamol labeling was not detectable in control subjects. In subjects with cardiac amyloidosis, cyano-flutemetamol labeling matched X-34- and cyano-PiB-labeled, and transthyretin- or lambda light chain-immunoreactive, amyloid deposits and was prevented by formic acid pre-treatment of myocardial sections. Cyano-flutemetamol mean fluorescence intensity, when adjusted for X-34 signal, was higher in the ATTRwt than the AL group. Cyano-flutemetamol integrated density correlated strongly with echocardiography measures of ventricular septal thickness and posterior wall thickness, and with heart mass. CONCLUSION: The high selectivity of cyano-flutemetamol binding to myocardial amyloid supports the diagnostic utility of [18F]flutemetamol PET imaging in patients with ATTR and AL types of cardiac amyloidosis.

Quantitative and qualitative analysis of individual experiences post botulinum toxin injection - United Kingdom Survey.

Introduction: In the United Kingdom (UK), complications that arise following the administration of Botulinum Toxin are reported to the Medicines and Health Regulatory Agency (MHRA) via the Yellow Card Reporting Scheme. Over the past decade, there has been a significant increase in the number of non-surgical aesthetic procedures. Concerns have been raised that the MHRA is not fully capturing complications in terms of volume and impact on patients. Aim: This novel study explores the lived experiences of individuals who have experienced an adverse event following administration of Botulinum Toxin for aesthetic purposes. Using a combination of qualitative and quantitative methodologies, this analysis evaluates data relating to long-lasting physical, psychological, emotional, and financial sequelae of complications arising from cosmetic Botulinum Toxin injections in the UK. Methods: A mixed method, qualitative and quantitative approach was adopted to gain comprehensive insights into patients' experiences. A focus group which comprised patient representatives, psychologists, and researchers reached a consensus on a 17-question survey which was disseminated via social media channels. Deductive thematic analysis was used to analyse coded themes. Furthermore, for secondary analysis, sentiment analysis was used computationally as an innovative approach to identify and categorise free text responses associated with sentiments using natural language processing (NLP). Results: In the study, 655 responses were received, with 287 (44%) of respondents completing all questions. The mean age of respondents was 42.6 years old. 94.1% of respondents identified as female. In the sample, 79% of respondents reported an adverse event following their procedure, with the most common event being reported as 'anxiety'. Findings revealed that 69% of respondents reported long-lasting adverse effects. From the responses, 68.4% reported not having recovered physically, 63.5% of respondents stated that they had not recovered emotionally from complications, and 61.7% said that they have not recovered psychologically. In addition, 84% of respondents stated that they do not know who regulates the aesthetics industry. Furthermore, 92% of participants reported that their clinic or practitioner did not inform them about the Yellow Card Reporting Scheme. The sentiment analysis using the AFINN Lexicon yielded adjusted scores ranging from -3 to +2, with a mean value of -1.58. Conclusion: This is the largest survey in the UK completed by patients who experienced an adverse outcome following the aesthetic administration of Botulinum Toxin. Our study highlights the extent of the challenges faced by patients who experience an adverse event from physical, emotional, psychological, and financial perspectives. The lack of awareness of MHRA reporting structures and the lack of regulation within the UK's cosmetic injectables sector represent a significant public health challenge.

MUC13 Cell Surface Mucin Limits Salmonella Typhimurium Infection by Protecting the Mucosal Epithelial Barrier.

BACKGROUND & AIMS: MUC13 cell surface mucin is highly expressed on the mucosal surface throughout the intestine, yet its role against bacterial infection is unknown. We investigated how MUC13 impacts Salmonella typhimurium (S Tm) infection and elucidated its mechanisms of action. METHODS: Muc13-/- and wild-type littermate mice were gavaged with 2 isogenic strains of S Tm after pre-conditioning with streptomycin. We assessed clinical parameters, cecal histology, local and systemic bacterial load, and proinflammatory cytokines after infection. Cecal enteroids and epithelial cell lines were used to evaluate the mechanism of MUC13 activity after infection. The interaction between bacterial SiiE and MUC13 was assessed by using siiE-deficient Salmonella. RESULTS: S Tm-infected Muc13-/- mice had increased disease activity, histologic damage, and higher local and systemic bacterial loads. Mechanistically, we found that S Tm binds to MUC13 through its giant SiiE adhesin and that MUC13 acts as a pathogen-binding decoy shed from the epithelial cell surface after pathogen engagement, limiting bacterial invasion. In addition, MUC13 reduces epithelial cell death and intestinal barrier breakdown by enhancing nuclear factor kappa B signaling during infection, independent of its decoy function. CONCLUSIONS: We show for the first time that MUC13 plays a critical role in antimicrobial defense against pathogenic S Tm at the intestinal mucosal surface by both acting as a releasable decoy limiting bacterial invasion and reducing pathogen-induced cell death. This further implicates the cell surface mucin family in mucosal defense from bacterial infection.

Exploring how and why social prescribing evaluations work: a realist review.

OBJECTIVE: The evidence base for social prescribing is inconclusive, and evaluations have been criticised for lacking rigour. This realist review sought to understand how and why social prescribing evaluations work or do not work. Findings from this review will contribute to the development of an evidence-based evaluation framework and reporting standards for social prescribing. DESIGN: A realist review. DATA SOURCES: ASSIA, CINAHL, Embase, Medline, PsycINFO, PubMed, Scopus Online, Social Care Online, Web of Science and grey literature. ELIGIBILITY CRITERIA: Documents reporting on social prescribing evaluations using any methods, published between 1998 and 2020 were included. Documents not reporting findings or lacking detail on methods for data collection and outcomes were excluded. ANALYSIS: Included documents were segregated into subcases based on methodology. Data relating to context, mechanisms and outcomes and the programme theory were extracted and context-mechanism-outcome configurations were developed. Meta-inferences were drawn from all subcases to refine the programme theory. RESULTS: 83 documents contributed to analysis. Generally, studies lacked in-depth descriptions of the methods and evaluation processes employed. A cyclical process of social prescribing evaluation was identified, involving preparation, conducting the study and interpretation. The analysis found that coproduction, alignment, research agency, sequential mixed-methods design and integration of findings all contributed to the development of an acceptable, high-quality social prescribing evaluation design. Context-mechanism-outcome configurations relating to these themes are reported. CONCLUSIONS: To develop the social prescribing evidence base and address gaps in our knowledge about the impact of social prescribing and how it works, evaluations must be high quality and acceptable to stakeholders. Development of an evaluation framework and reporting standards drawing on the findings of this realist review will support this aim. PROSPERO REGISTRATION NUMBER: CRD42020183065.