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A 57-year-old man with a background of chronic pancreatitis presented with acutely worsening abdominal pain and vomiting. He previously had a pancreatic duct stent in situ which had been removed 1 year prior to presentation. Initially suspected to be acute-on-chronic pancreatitis, a computed tomography (CT) scan of the abdomen and pelvis revealed an atrophic pancreas and a new mass in the pancreatic head, raising the suspicion of pancreatic malignancy. An urgent endoscopic ultrasound (EUS)-guided fine needle biopsy of the pancreatic head mass surprisingly revealed the presence of actinomyces colonies on histological evaluation. Prompt initiation of a prolonged antibiotic course led to significant clinical and radiological improvement. This case highlights the rare presentation of pancreatic actinomycosis which can often masquerade as malignancy. Although a gut commensal, actinomyces can elicit pathogenic effects if allowed to enter tissues through a breach in the mucosal lining such as following abdominal surgery or pancreatic duct intervention as observed in this case. Early recognition and appropriate treatment with antibiotics can lead to clinical recovery and complete resolution of the infection.
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We describe a precision medicine workflow, the integrated single nucleotide polymorphism network platform (iSNP), designed to determine the mechanisms by which SNPs affect cellular regulatory networks, and how SNP co-occurrences contribute to disease pathogenesis in ulcerative colitis (UC). Using SNP profiles of 378 UC patients we map the regulatory effects of the SNPs to a human signalling network containing protein-protein, miRNA-mRNA and transcription factor binding interactions. With unsupervised clustering algorithms we group these patient-specific networks into four distinct clusters driven by PRKCB, HLA, SNAI1/CEBPB/PTPN1 and VEGFA/XPO5/POLH hubs. The pathway analysis identifies calcium homeostasis, wound healing and cell motility as key processes in UC pathogenesis. Using transcriptomic data from an independent patient cohort, with three complementary validation approaches focusing on the SNP-affected genes, the patient specific modules and affected functions, we confirm the regulatory impact of non-coding SNPs. iSNP identified regulatory effects for disease-associated non-coding SNPs, and by predicting the patient-specific pathogenic processes, we propose a systems-level way to stratify patients.
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Colitis Ulcerosa , MicroARNs , Algoritmos , Colitis Ulcerosa/genética , Genómica , Humanos , Carioferinas/genética , Polimorfismo de Nucleótido SimpleRESUMEN
Patients with inflammatory bowel disease (IBD) are known to have perturbations in microRNA (miRNA) levels as well as altered miRNA regulation. Although experimental methods have provided initial insights into the functional consequences that may arise due to these changes, researchers are increasingly utilising novel bioinformatics approaches to further dissect the role of miRNAs in IBD. The recent exponential increase in transcriptomics datasets provides an excellent opportunity to further explore the role of miRNAs in IBD pathogenesis. To effectively understand miRNA-target gene interactions from gene expression data, multiple database resources are required, which have become available in recent years. In this technical note, we provide a step-by-step protocol for utilising these state-of-the-art resources, as well as systems biology approaches to understand the role of miRNAs in complex disease pathogenesis. We demonstrate through a case study example how to combine the resulting miRNA-target gene networks with transcriptomics data to find potential disease-specific miRNA regulators and miRNA-target genes in Crohn's disease. This approach could help to identify miRNAs that may have important disease-modifying effects in IBD and other complex disorders, and facilitate the discovery of novel therapeutic targets.
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Enfermedad de Crohn , Enfermedades Inflamatorias del Intestino , MicroARNs , Enfermedad de Crohn/genética , Redes Reguladoras de Genes , Humanos , Enfermedades Inflamatorias del Intestino/genética , MicroARNs/metabolismo , Transcriptoma/genéticaRESUMEN
Inflammatory bowel disease (IBD) is a chronic immune-mediated inflammatory disorder of the gastrointestinal tract that arises due to complex interactions between host genetic risk factors, environmental factors, and a dysbiotic gut microbiota. Although metagenomic approaches have attempted to characterise the dysbiosis occurring in IBD, the precise mechanistic pathways interlinking the gut microbiota and the intestinal mucosa are still yet to be unravelled. To deconvolute these complex interactions, a more reductionist approach involving microbial metabolites has been suggested. Bile acids have emerged as a key class of microbiota-associated metabolites that are perturbed in IBD patients. In recent years, metabolomics studies have revealed a consistent defect in bile acid metabolism with an increase in primary bile acids and a reduction in secondary bile acids in IBD patients. This review explores the evolving evidence that specific bile acid metabolites interact with intestinal epithelial and immune cells to contribute to the inflammatory milieu seen in IBD. Furthermore, we summarise evidence linking bile acids with intracellular pathways that are known to be relevant in IBD including autophagy, apoptosis, and the inflammasome pathway. Finally, we discuss how novel experimental and bioinformatics approaches could further advance our understanding of the role of bile acids and inform novel therapeutic strategies in IBD.
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Ácidos y Sales Biliares/fisiología , Microbioma Gastrointestinal/fisiología , Enfermedades Inflamatorias del Intestino/etiología , Animales , Ácidos y Sales Biliares/metabolismo , Disbiosis/patología , Humanos , Mucosa Intestinal/patologíaRESUMEN
The gastrointestinal (GI) tract harbours a complex microbial community, which contributes to its homeostasis. A disrupted microbiome can cause GI-related diseases, including inflammatory bowel disease (IBD), therefore identifying host-microbe interactions is crucial for better understanding gut health. Bacterial extracellular vesicles (BEVs), released into the gut lumen, can cross the mucus layer and access underlying immune cells. To study BEV-host interactions, we examined the influence of BEVs generated by the gut commensal bacterium, Bacteroides thetaiotaomicron, on host immune cells. Single-cell RNA sequencing data and host-microbe protein-protein interaction networks were used to predict the effect of BEVs on dendritic cells, macrophages and monocytes focusing on the Toll-like receptor (TLR) pathway. We identified biological processes affected in each immune cell type and cell-type specific processes including myeloid cell differentiation. TLR pathway analysis highlighted that BEV targets differ among cells and between the same cells in healthy versus disease (ulcerative colitis) conditions. The in silico findings were validated in BEV-monocyte co-cultures demonstrating the requirement for TLR4 and Toll-interleukin-1 receptor domain-containing adaptor protein (TIRAP) in BEV-elicited NF-kB activation. This study demonstrates that both cell-type and health status influence BEV-host communication. The results and the pipeline could facilitate BEV-based therapies for the treatment of IBD.
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Bacteroides thetaiotaomicron/metabolismo , Vesículas Extracelulares/metabolismo , Microbioma Gastrointestinal/inmunología , Enfermedades Inflamatorias del Intestino/inmunología , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Interacciones Microbiota-Huesped , Humanos , Enfermedades Inflamatorias del Intestino/microbiología , Macrófagos/inmunología , Macrófagos/metabolismo , Glicoproteínas de Membrana/antagonistas & inhibidores , Monocitos/inmunología , Monocitos/metabolismo , Mapas de Interacción de Proteínas , Receptores de Interleucina-1/antagonistas & inhibidores , Transducción de Señal , Receptor Toll-Like 4/antagonistas & inhibidores , Receptores Toll-Like/metabolismoRESUMEN
Inflammatory bowel disease (IBD) is a chronic immune-mediated condition arising due to complex interactions between multiple genetic and environmental factors. Despite recent advances, the pathogenesis of the condition is not fully understood and patients still experience suboptimal clinical outcomes. Over the past few years, investigators are increasingly capturing multi-omics data from patient cohorts to better characterise the disease. However, reaching clinically translatable endpoints from these complex multi-omics datasets is an arduous task. Network biology, a branch of systems biology that utilises mathematical graph theory to represent, integrate and analyse biological data through networks, will be key to addressing this challenge. In this narrative review, we provide an overview of various types of network biology approaches that have been utilised in IBD including protein-protein interaction networks, metabolic networks, gene regulatory networks and gene co-expression networks. We also include examples of multi-layered networks that have combined various network types to gain deeper insights into IBD pathogenesis. Finally, we discuss the need to incorporate other data sources including metabolomic, histopathological, and high-quality clinical meta-data. Together with more robust network data integration and analysis frameworks, such efforts have the potential to realise the key goal of precision medicine in IBD.
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Intercellular communication mediated by cytokines is critical to the development of immune responses, particularly in the context of infectious and inflammatory diseases. By releasing these small molecular weight peptides, the source cells can influence numerous intracellular processes in the target cells, including the secretion of other cytokines downstream. However, there are no readily available bioinformatic resources that can model cytokine-cytokine interactions. In this effort, we built a communication map between major tissues and blood cells that reveals how cytokine-mediated intercellular networks form during homeostatic conditions. We collated the most prevalent cytokines from the literature and assigned the proteins and their corresponding receptors to source tissue and blood cell types based on enriched consensus RNA-Seq data from the Human Protein Atlas database. To assign more confidence to the interactions, we integrated the literature information on cell-cytokine interactions from two systems of immunology databases, immuneXpresso and ImmunoGlobe. From the collated information, we defined two metanetworks: a cell-cell communication network connected by cytokines; and a cytokine-cytokine interaction network depicting the potential ways in which cytokines can affect the activity of each other. Using expression data from disease states, we then applied this resource to reveal perturbations in cytokine-mediated intercellular signalling in inflammatory and infectious diseases (ulcerative colitis and COVID-19, respectively). For ulcerative colitis, with CytokineLink, we demonstrated a significant rewiring of cytokine-mediated intercellular communication between non-inflamed and inflamed colonic tissues. For COVID-19, we were able to identify cell types and cytokine interactions following SARS-CoV-2 infection, highlighting important cytokine interactions that might contribute to severe illness in a subgroup of patients. Such findings have the potential to inform the development of novel, cytokine-targeted therapeutic strategies. CytokineLink is freely available for the scientific community through the NDEx platform and the project github repository.
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COVID-19/inmunología , Citocinas/metabolismo , Inmunidad , Enfermedades Inflamatorias del Intestino/inmunología , Comunicación Celular , Colitis Ulcerosa/inmunología , Colitis Ulcerosa/patología , Bases de Datos Genéticas , Humanos , Enfermedades Inflamatorias del Intestino/patología , Transducción de SeñalRESUMEN
Background and study aims Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has emerged as an important method for obtaining a preoperative tissue diagnosis for suspected cholangiocarcinoma. However, doubts remain about test sensitivity. This study assessed the value and limitations of EUS-FNA in clinical practice. Patients and methods Patients undergoing EUS-FNA for biliary strictures/masses at a UK tertiary referral center from 2005 to 2014 were prospectively enrolled. Data on EUS-FNA findings, histology, and endoscopy and patient outcomes were collected to evaluate test performance and identify factors predictive of an inaccurate diagnostic result. Results Ninety-seven patients underwent a total of 112 EUS-FNA procedures. Overall test sensitivity for an initial EUS-FNA for suspected cholangiocarcinoma was 75â% (95â% CI 64â%-84â%), with specificity 100â% (95â% CI 85â%-100â%) and negative predictive value 0.62 (95â% CI 0.47-0.75). Hilar lesions, the presence of a biliary stent, and a diagnosis of PSC were significantly independently associated with an inaccurate result. For the most difficult cases, repeat sampling and use of the Papanicolaou cytopathology grading scale led to an increase in test sensitivity from 17â% to 100â% ( P â=â0.015) with no loss of specificity. Conclusions EUS-FNA was found to be a useful method for obtaining a preoperative tissue diagnosis for patients with suspected cholangiocarcinoma. This study identified markers that can reduce test accuracy and measures that can improve test performance of EUS-FNA.
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PURPOSE: A growing body of preclinical and observational research suggests that statins have potential as a therapeutic strategy in patients with cancer. This systematic review of randomised controlled trials (RCTs) in patients with solid tumours aimed to determine the efficacy of statin therapy on mortality outcomes, their safety profile and the risk of bias of included studies. METHODS: Full-text articles comparing statin therapy versus control in solid tumours and reporting mortality outcomes were identified from Medline and Embase from conception to February 2020. A systematic review with qualitative (primarily) and quantitative synthesis was conducted. This systematic review was prospectively registered (Prospero registration CRD42018116364). RESULTS: Eleven trials of 2165 patients were included. Primary tumour sites investigated included lung, colorectal, gastro-oesophageal, pancreatic and liver. Most trials recruited patients with advanced malignancy and used sub-maximal statin doses for relatively short durations. Aside from one trial which demonstrated benefit with allocation to pravastatin 40 mg in hepatocellular carcinoma, the remaining ten trials did not demonstrate efficacy with statins. The pooled hazard ratio for all-cause mortality with allocation to pravastatin in patients with hepatocellular carcinoma in two trials was 0.69 (95% confidence interval CI 0.30-1.61). Study estimates were imprecise. There were no clinically important differences in statin-related adverse events between groups. Overall, included trials were deemed low risk of bias. CONCLUSION: The trial evidence is not sufficiently robust to confirm or refute the efficacy and safety of statins in patients with solid malignant tumours. Study and patient characteristics may explain this uncertainty. The potential role of high-dose statins in adjuvant settings deserves further research.
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Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Neoplasias/tratamiento farmacológico , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Neoplasias/mortalidad , Pravastatina/administración & dosificación , Pravastatina/efectos adversos , Supervivencia sin Progresión , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de TiempoRESUMEN
Adult-onset immunoglobulin (IgA) vasculitis presenting as terminal ileitis is a rare clinical encounter which can mimic inflammatory bowel disease or infectious gastroenteritis. A high index of clinical suspicion is required to reach the correct diagnosis and to implement the appropriate management plans. Herein, we report a case of an elderly female presenting with a short history of abdominal pain, vomiting, bloody diarrhoea, fatigue and reduced appetite. Based on the blood tests and imaging, she was initially managed as having an infective or inflammatory bowel condition. Subsequently, she developed a vasculitic rash in her lower limbs with accompanying renal involvement including haematuria and sub-nephrotic range proteinuria. She underwent a renal biopsy which confirmed the diagnosis of IgA vasculitis. She was started on a course of corticosteroid therapy which induced clinical remission.
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Enfermedad de Crohn , Vasculitis por IgA , Vasculitis , Adulto , Anciano , Femenino , Hemorragia Gastrointestinal , Humanos , Vasculitis por IgA/complicaciones , Vasculitis por IgA/diagnóstico , Inmunoglobulina ARESUMEN
Tragically, many of the infections and deaths recorded in the global coronavirus disease 2019 (COVID-19) pandemic have occurred in healthcare workers. Some have attributed this to inadequate provision of personal protective equipment (PPE). In the UK, several organisations have voiced their concerns that the national PPE guidance issued by Public Health England is inadequate. Despite recent revisions to these guidelines, concerns remain that they offer insufficient protection to frontline NHS healthcare workers. In this report, we evaluate whether these concerns are merited, through critical appraisal of the available evidence, review of international PPE guidance, and consideration of the ethical implications.
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RATIONALE AND OBJECTIVE: To evaluate the relationship between receipt of annual physicals and the receipt of provider recommendation for preventive services, during a period when Medicare did not cover annual physicals (before 2011). METHODS: Electronic medical records of patients aged 65 years and older from a US health care system were extracted for the 2001 to 2007 period. A fixed-effects logistic model was used to assess the relationship between receipt of periodic health examination (PHE) and receipt of provider recommendation for mammogram screening for 6466 female Medicare beneficiaries. Logistic regression models were used to assess the relationship between receipt of PHE and receipt of provider recommendation for colonoscopy screening and pneumococcal vaccination for 10 318 Medicare beneficiaries. Nine primary care providers from the network were also interviewed, selected by random sampling stratified by care model. RESULTS: Electronic medical record analyses suggest that patients with a PHE were more likely to obtain provider recommendations for mammogram screening (OR = 2.17, P < 0.0001), colonoscopy screening (OR = 1.54, P < 0.0001), and pneumococcal vaccination (OR = 1.10, P < 0.0001). Providers suggested that prevention care quality improves with the PHE because certain screening measures (eg, skin cancer screening, breast exam) would be neglected without it, and healthy patients could miss recommended preventive services entirely. Without the PHE, some providers reported having tried to incorporate discussions of preventive services by scheduling more frequent follow-up chronic care visits than they would have otherwise, and some routinely charged Medicare for a more complex follow-up visit than they would have charged without the preventive service discussions. CONCLUSION: Periodic health examination is important in connecting patients to recommended preventive services. Provider interviews suggested that, indirectly, Medicare ended up paying for the PHE via greater frequency of follow-up visits or higher visit charges from providers integrating the services with other visits.
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Detección Precoz del Cáncer , Examen Físico , Vacunas Neumococicas/administración & dosificación , Servicios Preventivos de Salud , Anciano , Detección Precoz del Cáncer/métodos , Detección Precoz del Cáncer/estadística & datos numéricos , Registros Electrónicos de Salud/estadística & datos numéricos , Femenino , Humanos , Masculino , Medicare/economía , Medicare/estadística & datos numéricos , Examen Físico/economía , Examen Físico/métodos , Examen Físico/normas , Servicios Preventivos de Salud/economía , Servicios Preventivos de Salud/métodos , Servicios Preventivos de Salud/normas , Estados Unidos/epidemiologíaRESUMEN
We performed an updated meta-analysis incorporating the results of recent randomised controlled trials (RCTs) to measure the effectiveness of probiotic supplementation in preventing necrotising enterocolitis (NEC) and death in very low-birth-weight (VLBW) infants, and to investigate any differences in efficacy by probiotic agent. Using meta-regression analysis, we assessed the contribution of other measured variables on the overall effect size and between-study variability. CONCLUSION: Overall, probiotics lead to significant reductions in NEC incidence and mortality in VLBW infants. Differences in probiotic agents and the influence of prenatal steroids and feeding regimens may explain the differences in outcomes between studies.