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A new study by the Cornall group provides new insights into the importance of zinc in human health.
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Pathogenesis of Fistulating Crohn's Disease: A Review.
Sustained, transmural inflammation of the bowel wall may result in the development of a fistula in Crohn's disease (CD). Fistula formation is a recognized complication and cause of morbidity, occurring in 40% of patients with CD. Despite advanced treatment, one-third of patients experience recurrent fistulae. Development of targeting treatment for fistulae will be dependent on a more in depth understanding of its pathogenesis. Presently, pathogenesis of CD-associated fistulae remains poorly defined, in part due to the lack of accepted in vitro tissue models recapitulating the pathogenic cellular lesions linked to fistulae and limited in vivo models. This review provides a synthesis of the existing knowledge of the histopathological, immune, cellular, genetic, and microbial contributions to the pathogenesis of CD-associated fistulae including the widely accredited contribution of epithelial-to-mesenchymal transition, upregulation of matrix metalloproteinases, and overexpression of invasive molecules, resulting in tissue remodeling and subsequent fistula formation. We conclude by exploring how we might utilize advancing technologies to verify and broaden our current understanding while exploring novel causal pathways to provide further inroads to future therapeutic targets.
Tracking in situ checkpoint inhibitor-bound target T cells in patients with checkpoint-induced colitis.
The success of checkpoint inhibitors (CPIs) for cancer has been tempered by immune-related adverse effects including colitis. CPI-induced colitis is hallmarked by expansion of resident mucosal IFNγ cytotoxic CD8+ T cells, but how these arise is unclear. Here, we track CPI-bound T cells in intestinal tissue using multimodal single-cell and subcellular spatial transcriptomics (ST). Target occupancy was increased in inflamed tissue, with drug-bound T cells located in distinct microdomains distinguished by specific intercellular signaling and transcriptional gradients. CPI-bound cells were largely CD4+ T cells, including enrichment in CPI-bound peripheral helper, follicular helper, and regulatory T cells. IFNγ CD8+ T cells emerged from both tissue-resident memory (TRM) and peripheral populations, displayed more restricted target occupancy profiles, and co-localized with damaged epithelial microdomains lacking effective regulatory cues. Our multimodal analysis identifies causal pathways and constitutes a resource to inform novel preventive strategies.
Geography Influences Susceptibility to SARS-CoV-2 Serological Response in Patients With Inflammatory Bowel Disease: Multinational Analysis From the ICARUS-IBD Consortium.
BACKGROUND: Beyond systematic reviews and meta-analyses, there have been no direct studies of serological response to COVID-19 in patients with inflammatory bowel disease (IBD) across continents. In particular, there has been limited data from Asia, with no data reported from India. The ICARUS-IBD (International study of COVID-19 Antibody Response Under Sustained immunosuppression in IBD) consortium assessed serological response to SARS-CoV-2 in patients with IBD in North America, Europe, and Asia. METHODS: The ICARUS-IBD study is a multicenter observational cohort study spanning sites in 7 countries. We report seroprevalence data from 2303 patients with IBD before COVID-19 vaccination between May 2020 and November 2021. SARS-CoV-2 anti-spike and anti-nucleocapsid antibodies were analyzed. RESULTS: The highest and lowest SARS-CoV-2 anti-spike seropositivity rates were found in Asia (81.2% in Chandigarh and 57.9% in Delhi, India; and 0% in Hong Kong). By multivariable analysis, country (India: odds ratio [OR], 18.01; 95% confidence interval [CI], 12.03-26.95; P < .0001; United Kingdom: OR, 2.43; 95% CI, 1.58-3.72; P < .0001; United States: OR, 2.21; 95% CI, 1.27-3.85; P = .005), male sex (OR, 1.46; 95% CI, 1.07-1.99; P = .016), and diabetes (OR, 2.37; 95% CI, 1.04-5.46; P = .039) conferred higher seropositivity rates. Biological therapies associated with lower seroprevalence (OR, 0.22; 95% CI, 0.15-0.33; P < .0001). Multiple linear regression showed associations between anti-spike and anti-nucleocapsid titers with medications (P < .0001) but not with country (P = .3841). CONCLUSIONS: While the effects of medications on anti-SARS-CoV-2 antibody titers in patients with IBD were consistent across sites, geographical location conferred the highest risk of susceptibility to serologically detectable SARS-CoV-2 infection. Over half of IBD patients in India were seropositive prior to vaccination. These insights can help to inform shielding advice, therapeutic choices, and vaccine strategies in IBD patients for COVID-19 and future viral challenges.
Early management of acute severe UC in the biologics era: development and international validation of a prognostic clinical index to predict steroid response.
OBJECTIVES: We aimed to determine whether changes in acute severe colitis (ASC) management have translated to improved outcomes and to develop a simple model predicting steroid non-response on admission. DESIGN: Outcomes of 131 adult ASC admissions (117 patients) in Oxford, UK between 2015 and 2019 were compared with data from 1992 to 1993. All patients received standard treatment with intravenous corticosteroids and endoscopic disease activity scoring (Ulcerative Colitis Endoscopic Index of Severity (UCEIS)). Steroid non-response was defined as receiving medical rescue therapy or surgery. A predictive model developed in the Oxford cohort was validated in Australia and India (Gold Coast University Hospital 2015-2020, n=110; All India Institute of Medical Sciences, New Delhi 2018-2020, n=62). RESULTS: In the 2015-2019 Oxford cohort, 15% required colectomy during admission vs 29% in 1992-1993 (p=0.033), while 71 (54%) patients received medical rescue therapy (27% ciclosporin, 27% anti-tumour necrosis factor, compared with 27% ciclosporin in 1992-1993 (p=0.0015). Admission C reactive protein (CRP) (false discovery rate, p=0.00066), albumin (0.0066) and UCEIS scores (0.015) predicted steroid non-response. A four-point model was developed involving CRP of ≥100 mg/L (one point), albumin of ≤25 g/L (one point), and UCEIS score of ≥4 (1 point) or ≥7 (2 points). Patients scoring 0, 1, 2, 3 and 4 in the validation cohorts had steroid response rates of 100, 75.0%, 54.9%, 18.2% and 0%, respectively. Scoring of ≥3 was 84% (95% CI 0.70 to 0.98) predictive of steroid failure (OR 11.9, 95% CI 10.8 to 13.0). Colectomy rates in the validation cohorts were were 8%-11%. CONCLUSIONS: Emergency colectomy rates for ASC have halved in 25 years to 8%-15% worldwide. Patients who will not respond to corticosteroids are readily identified on admission and may be prioritised for early intensification of therapy.
Pain, well-being, body image and cosmesis: a comparison of single-port and four-port laparoscopic cholecystectomy.
BACKGROUND: This study aims to compare post-operative pain, well-being, body image and cosmesis in SILS cholecystectomy and four-port laparoscopic cholecystectomy (FPLC). MATERIAL AND METHODS: Forty-two consecutive patients (15 SILS, 27 FPLC) undergoing elective cholecystectomy were included in the study. Peri-operative pain, well-being, body image and cosmesis were evaluated using validated assessment tools. RESULTS: Significantly lower pain scores were reported one week post-operatively in the SILS group (5.6 vs 8.3; p = 0.035). No significant difference was found in analgesic requirements, physical or mental well-being at any time interval. Significantly higher (favourable) body image questionnaire scores were reported in the SILS group at one week (5.4 v 4.5; p < 0.01), two weeks (5.6 vs 4.8; p < 0.01) and one month (5.7 vs 5.0; p < 0.01) post-operatively. CONCLUSION: SILS patients have significantly reduced one-week pain scores and there was no significant difference in well-being between the two groups. Patients who underwent SILS had improved body image and cosmesis. If both techniques are found to be equivalent concerning safety, cost, learning curve and availability, SILS may play a key role in the new era of patient choice.
A randomised comparative study evaluating learning curves of novices in a basic single-incision laparoscopic surgery task.
OBJECTIVE: There is currently no objective quantification of the temporal changes in performance associated with a novice surgeon learning single-incision laparoscopic surgery (SILS) operative tasks. Analysing learning curves allows us to objectively quantify performance. The aim was to evaluate if the rate of learning and ultimate proficiency level reached in SILS when using straight or articulating instruments is different to conventional laparoscopy and if training in laparoscopy influences learning or proficiency for SILS. DESIGN AND SETTING: Thirty-six surgically naive medical students were randomised to complete the validated peg transfer task over 50 repetitions using a conventional laparoscopic set-up, SILS set-up with straight instruments or articulated instruments or SILS set-up after having reached proficiency using a conventional laparoscopy. RESULTS: There was a significant increased overall proficiency between the group trained in conventional laparoscopy and all other groups (p
Evaluating systemic stress response in single port vs. multi-port laparoscopic cholecystectomy.
BACKGROUND AND AIMS: Acute-phase proteins and inflammatory cytokines mediate measurable responses to surgical trauma, which are proportional to the extent of tissue injury and correlate with post-operative outcome. By comparing systemic stress following multi-port (LC) and single-incision laparoscopic cholecystectomy (SILC), we aim to determine whether reduced incision size induces a reduced stress response. METHODS: Thirty-five consecutive patients were included, 11 underwent SILC (mean ± SEM; age 44.8 ± 3.88 year; BMI 27 ± 1.44 kg/m(2)) and 24 underwent LC (56.17 ± 2.80 year; 31.72 ± 1.07 kg/m(2), p
Spatial fibroblast niches define Crohn's fistulae.
Crohn's disease often presents with fistulae, abnormal tunnels that connect the intestine to the skin or other organs. Despite their profound effect on morbidity, the molecular basis of fistula formation remains unclear, largely owing to the challenge of capturing intact fistula tracts and their inherent heterogeneity1-3. Here we construct a subcellular-resolution spatial atlas of 68 intestinal fistulae spanning diverse anatomical locations. We describe fistula-associated epithelial, immune and stromal cell states, revealing abnormal zonation of growth factors and morphogens linked to establishment of tunnelling anatomy. We identify fistula-associated stromal (FAS) fibroblasts, which are assembled in concentric layers: a proliferative, lumen-adjacent zone beneath neutrophil and macrophage-rich granulation tissue, an active lesion core of FAS cells and a quiescent, pro-fibrotic outer zone. We examine the architecture of the extracellular matrix in the fistula tract and demonstrate that FAS populations associate with distinct collagen structures, exhibiting properties ranging from proliferation, migration and extracellular matrix remodelling to dense collagen deposition and fibrosis. We define niches supporting epithelialization of fistula tunnels and a FAS-like population that is detected at the base of ulcers in non-penetrating Crohn's disease. Our study demonstrates that common molecular pathways and cellular niches underpin fistulae across intestinal locations, revealing the cellular protagonists of fistula establishment and persistence. This resource will inform the development of model systems and interventions to mitigate aberrant fibroblast activity while preserving their regenerative properties in Crohn's disease.
Development and validation of peripheral blood DNA methylation signatures to predict response to biological therapy in adults with Crohn's disease (EPIC-CD): an epigenome-wide association study.
BACKGROUND: Biological therapeutics are widely used in Crohn's disease, with evidence of efficacy from randomised trials and real-world experience. Primary non-response is a common, poorly understood problem. We aimed to assess blood methylation as a predictor of response to adalimumab, vedolizumab, or ustekinumab in patients with Crohn's disease. METHODS: This epigenome-wide association study used data from two ongoing biobanks (one from the Amsterdam University Medical Centre, University of Amsterdam, Amsterdam, Netherlands [discovery cohort] and the other from the John Radcliffe Hospital, Oxford, UK [validation cohort]) that recruited patients between Oct 1, 2009, and June 17, 2022. Adult participants (age ≥18 years) with active symptomatic and endoscopic Crohn's disease who were scheduled to start adalimumab, vedolizumab, or ustekinumab treatment were included. Patients with ongoing malignancy or serious concomitant inflammatory diseases were excluded. Treatment response was assessed after a median of 28 weeks of treatment (IQR 18-36). Response was defined as a combination of endoscopic criteria (50% or more reduction in the Simple Endoscopic Score for Crohn's Disease) with either clinical or biochemical criteria (corticosteroid-free clinical response: ≥3 point decrease in Harvey-Bradshaw Index [HBI] score or remission [HBI ≤4] and no systemic steroids at follow up; biochemical response: C-reactive protein reduction ≥50% or ≤5 mg/L and faecal calprotectin reduction ≥50% or ≤250 μg/g) compared with baseline. Epigenome-wide DNA methylation and transcriptome-wide gene expression analyses were done on whole peripheral blood leukocyte samples that were collected before the start of treatment. To identify baseline DNA methylation markers associated with response or non-response to treatment, we performed supervised machine learning through stability selected gradient boosting. In a post-hoc analysis, we compared our DNA methylation-based prediction model with clinical decision support tools (CDSTs). FINDINGS: We profiled the peripheral blood DNA methylome of 273 adults with Crohn's disease scheduled to start adalimumab, vedolizumab, or ustekinumab in the discovery (Amsterdam, n=183; 108 [59·0%] female and 75 [41·0%] male) and the validation cohort (Oxford, n=90; 46 [51·1%] female and 44 [48·9%] male). In the discovery cohort, we defined a panel of DNA methylation biomarkers that were associated with combined endoscopic and clinical or biochemical response to adalimumab (18 markers), vedolizumab (25 markers), or ustekinumab (68 markers), with an area under the curve (AUC) of 0·86 (95% CI 0·58-0·97) for adalimumab, 0·87 (0·67-0·98) for vedolizumab, and 0·89 (0·76-1·00) for ustekinumab. Validation in the Oxford cohort yielded an AUC of 0·25 (0·10-0·35) for adalimumab, 0·75 (0·65-0·85) for vedolizumab, and 0·75 (0·65-0·87) for ustekinumab. In comparison, implementing the CDSTs in the validation cohort yielded an AUC of 0·56 (0·44-0·68) for vedolizumab and 0·66 (0·54-0·77) for ustekinumab. Previous anti-TNF exposure was associated with a reduction in accuracy of the methylation models for vedolizumab (0·66 [0·55-0·73]) and ustekinumab (0·63 [0·52-0·70]) when analysed in the validation cohort. INTERPRETATION: Our findings provide evidence for the potential use of DNA methylation as a modality for personalised medicine for Crohn's disease by predicting response to vedolizumab and ustekinumab. The models were more accurate in biologically naive patients and outperform available vedolizumab and ustekinumab CDSTs. We were unable to predict response to adalimumab. The vedolizumab and ustekinumab prediction models are currently being tested in a multicentre randomised clinical trial. FUNDING: The Leona M and Harry B Helmsley Charitable Trust.
An Overview of Targeted Therapies in Acute Myeloid Leukemia.
Acute myeloid leukemia (AML) is the most aggressive adult leukemia, characterized by clonal differentiation arrest of progenitor or precursor hematopoietic cells. Intense preclinical and clinical research has led to regulatory approval of several targeted therapeutics, administered either as single agents or as combination therapies. However, the majority of patients still face a poor prognosis and disease relapse frequently occurs due to selection of therapy-resistant clones. Hence, more effective novel therapies, most likely as innovative, rational combination therapies, are urgently needed. Chromosomal aberrations, gene mutations, and epigenetic alterations drive AML pathogenesis but concurrently provide vulnerabilities to specifically target leukemic cells. Other molecules, either aberrantly active and/or overexpressed in leukemic stem cells, may also be leveraged for therapeutic benefit. This concise review of targeted therapies for AML treatment, which are either approved or are being actively investigated in clinical trials or recent preclinical studies, provides a flavor of the direction of travel, but also highlights the current challenges in AML treatment.