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The process of microencapsulation and the development of microparticle-based drug formulations have gained increased pharmaceutical interest, particularly for drug delivery and bacterial-encapsulation purposes for probiotic delivery. Existing studies have examined microcomposite (MC) responses to gastrointestinal (GI) conditions with the aim of controlling disintegration, and thus release, across the small and large bowel. However, the delivery of MCs which remain intact, without degrading, could act as bacterial growth scaffolds or materials providing a prebiotic support, conferring potentially beneficial GI health properties. This present study employs prilling as a method to produce a portfolio of MCs using a variety of biopolymers (alginate, chitosan, pectin and gellan gum) with a range of MC diameters and density compositions. Fluorescent probes are co-encapsulated within each MC to enable flow-cytometry directed release profile assessments following exposure to chemical simulated gastric and intestinal digestion conditions. We observe that MC size, gel-strength, density, and biopolymer material all influence response to gastric and intestinal conditions. Gellan gum (GG) MCs demonstrated complete resistance to disintegration throughout GI-simulation in the stomach and small intestine. Considering these MCs could reach the colon intact, we then examined how such MCs, doped with prebiotic growth supporting carboxymethyl cellulose (CMC) polymers, could impact microbial communities using a bioreactor model of the colonic microbiome. Following supplementation with GGCMC MCs, mucosal bacterial diversity (using 16 s rRNA sequencing and Shannon entropy and observed feature diversity metrics) and taxonomic composition changes were observed. Concentrations of short chain fatty acid (SCFA) metabolites were also found to be altered. This is the first study to comprehensivelyexamine how MC physicochemistry can be manipulated to tailor MCs to have the desired GI release performance and subsequently, how GI-resistant MCs could have influential microbial altering properties and be adopted in novel prebiotic strategies.
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Microbioma Gastrointestinal , Prebióticos , Prebióticos/administração & dosagem , Microbioma Gastrointestinal/efeitos dos fármacos , Bactérias , Biopolímeros/química , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Humanos , Polissacarídeos Bacterianos/químicaRESUMO
Background: Primary sclerosing cholangitis (PSC) is one of the leading indications for liver transplantation in Europe, and a major risk factor for cancer in inflammatory bowel disease (IBD). However, it is not known how the epidemiology of PSC will change as that of IBD evolves. The aim of this study is to provide nationwide statistics on the past and current prevalence of PSC and IBD across England, and forecast how this is likely to change over time. Methods: We accessed and analysed a nationwide population-based administrative healthcare registry, which houses prospectively accrued data since April 1st 2001. In so doing, the past and current prevalence of PSC-IBD and IBD alone was determined among 18-60-year-olds in England, alongside average annual percentage change rates (AAPC), between the 1st of January 2015 and 2020. Past and current prevalence data, alongside trends in incidence and event-free survival rates, were then used to forecast future prevalence between 2021 and 2027. Findings: In 2015, the prevalence of PSC with prior IBD diagnosis was 5.0 per 100,000 population, rising to 5.7 when including those with IBD diagnosed after PSC. In 2020, prevalence increased to 7.6 (8.6 accounting for IBD developing after PSC), yielding an AAPC of 8.8. In 2027, PSC-IBD prevalence is forecast to be 11.7 (95% prediction interval [PI]: 10.8-12.7), and 13.3 when accounting for IBD developing after PSC (AAPC: 6.4; 95% PI: 5.3-7.5). Comparatively, the prevalence of IBD alone rose among 18-60-year-olds from 384.3 in 2015 to 538.7 in 2020 (AAPC 7.0), and forecast to increase to 742.5 by 2027 (95% PI: 736.4-748.0; AAPC: 4.7, 95% PI: 4.6-4.8). Interpretation: The rate of growth in PSC-IBD is predicted to exceed IBD-alone. Further research is needed to understand changes in disease epidemiology, including aetiological drivers of developing (invariably progressive) liver disease in IBD, and the implications of rising case burden on health care resources. Funding: This study was supported by an unrestricted grant provided by Gilead Sciences.
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This is the first of two articles from the joint British Society of Gastroenterology Nurses association and Research Committee working group. The group is dedicated to signposting and improving access to research for specialist nurses working in gastroenterology and hepatology. This article is an introduction to the significance and structure of the National Institute for Health Research clinical research landscape in the UK and the importance of encouraging nurse engagement in research. This paper describes and 'demystifies' the clinical trials infrastructure in the UK, which is one of the most organised in the world. Going forwards this working group will organise and conduct educational events encouraging specialist nurses to become more aware of and engage in clinical research in their area of practice.
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The first British Society of Gastroenterology (BSG) and Healthcare Infection Society (HIS)-endorsed faecal microbiota transplant (FMT) guidelines were published in 2018. Over the past 5 years, there has been considerable growth in the evidence base (including publication of outcomes from large national FMT registries), necessitating an updated critical review of the literature and a second edition of the BSG/HIS FMT guidelines. These have been produced in accordance with National Institute for Health and Care Excellence-accredited methodology, thus have particular relevance for UK-based clinicians, but are intended to be of pertinence internationally. This second edition of the guidelines have been divided into recommendations, good practice points and recommendations against certain practices. With respect to FMT for Clostridioides difficile infection (CDI), key focus areas centred around timing of administration, increasing clinical experience of encapsulated FMT preparations and optimising donor screening. The latter topic is of particular relevance given the COVID-19 pandemic, and cases of patient morbidity and mortality resulting from FMT-related pathogen transmission. The guidelines also considered emergent literature on the use of FMT in non-CDI settings (including both gastrointestinal and non-gastrointestinal indications), reviewing relevant randomised controlled trials. Recommendations are provided regarding special areas (including compassionate FMT use), and considerations regarding the evolving landscape of FMT and microbiome therapeutics.
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Infecções por Clostridium , Transplante de Microbiota Fecal , Gastroenterologia , Transplante de Microbiota Fecal/métodos , Humanos , Infecções por Clostridium/terapia , Gastroenterologia/normas , COVID-19/terapia , SARS-CoV-2 , Recidiva , Clostridioides difficile , Reino Unido , Sociedades MédicasRESUMO
In this second part of an introduction to research for gastroenterology and hepatology nurses, we aim to build on the first article that introduced the significance and structure of the National Institute for Health and Care Research clinical research landscape in the UK and the importance of nurse engagement. This article introduces possible career pathways available in the profession and specialty. Practical information on how to start research is provided, including an overview of the education, training and support required for a career in research delivery and academic research. Some of the potential barriers to nursing research careers are highlighted, and solutions to navigate a successful career in nursing research are proposed.
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Inflammatory bowel diseases (IBDs) are chronic intestinal disorders often characterized by a dysregulation of T cells, specifically T helper (Th) 1, 17 and T regulatory (Treg) repertoire. Increasing evidence demonstrates that dietary polyphenols from Mangifera indica L. extract (MIE, commonly known as mango) mitigate intestinal inflammation and splenic Th17/Treg ratio. In this study, we aimed to dissect the immunomodulatory and anti-inflammatory properties of MIE using a reverse translational approach, by initially using blood from an adult IBD inception cohort and then investigating the mechanism of action in a preclinical model of T cell-driven colitis. Of clinical relevance, MIE modulates TNF-α and IL-17 levels in LPS spiked sera from IBD patients as an ex vivo model of intestinal barrier breakdown. Preclinically, therapeutic administration of MIE significantly reduced colitis severity, pathogenic T-cell intestinal infiltrate and intestinal pro-inflammatory mediators (IL-6, IL-17A, TNF-α, IL-2, IL-22). Moreover, MIE reversed colitis-induced gut permeability and restored tight junction functionality and intestinal metabolites. Mechanistic insights revealed MIE had direct effects on blood vascular endothelial cells, blocking TNF-α/IFN-γ-induced up-regulation of COX-2 and the DP2 receptors. Collectively, we demonstrate the therapeutic potential of MIE to reverse the immunological perturbance during the onset of colitis and dampen the systemic inflammatory response, paving the way for its clinical use as nutraceutical and/or functional food.
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Colite , Doenças Inflamatórias Intestinais , Mangifera , Adulto , Humanos , Animais , Fator de Necrose Tumoral alfa/metabolismo , Células Endoteliais/metabolismo , Mucosa Intestinal , Modelos Animais de DoençasRESUMO
AIMS: Anemia is the most common extraintestinal complication of inflammatory bowel disease (IBD), with approximately half of cases caused by iron deficiency (ID). Intravenous iron is the preferred ID anemia (IDA) treatment where oral iron is contraindicated, ineffective or not tolerated, or where ID correction is urgent. The objective was to evaluate the cost-utility of ferric derisomaltose (FDI) versus ferric carboxymaltose (FCM) in patients with IBD and IDA in England, in whom IV iron treatment is preferred. MATERIALS AND METHODS: A patient-level simulation model was developed, capturing quality of life (QoL) differences based on SF-36v2 data from the PHOSPHARE-IBD randomized controlled trial, monitoring and incidence of post-infusion hypophosphatemia, and number of iron infusions required. Analyses were conducted over a five-year time horizon from the Department of Health and Social Care (DHSC) perspective, with healthcare provider and societal perspectives adopted in separate analyses. Future costs and effects were discounted at 3.5% per annum and one-way and probabilistic sensitivity analyses were performed. RESULTS: FDI increased quality-adjusted life expectancy by 0.075 QALYs versus FCM from 2.57 QALYs to 2.65 QALYs per patient. Patients receiving FDI required 1.63 fewer iron infusions over the five-year time horizon, driving infusion-related cost savings of GBP 496 per patient (GBP 2,188 versus GBP 1,692) from the DHSC perspective. Costs of monitoring and treating hypophosphatemia after FCM were GBP 226, yielding total savings of GBP 722 per patient (GBP 2,414 versus GBP 1,692) over the five-year time horizon. FDI also led to reduced costs versus FCM in the societal and provider analyses and was therefore the dominant intervention across all three perspectives. LIMITATIONS: The analysis did not capture patient adherence, hypophosphatemic osteomalacia, or fractures. CONCLUSIONS: Results showed that FDI improved patient QoL and reduced direct healthcare expenditure versus FCM in patients with IBD and IDA in England.
Ferric derisomaltose (FDI) is an intravenous iron approved for the treatment of clinically diagnosed iron deficiency in the United Kingdom (UK), and can be an important therapeutic option for patients with inflammatory bowel disease (IBD), who require regular and rapid iron replenishment. Ferric carboxymaltose (FCM) is the sole alternative intravenous iron formulation available in the UK, but is associated with reduced blood phosphate levels, potentially causing fatigue and weakening of the bones. We conducted an economic analysis to weigh the costs and clinical outcomes associated with FDI and FCM in the UK, for patients with IBD and iron deficiency anemia (IDA). The main clinical difference we investigated was reduced blood phosphate levels, which occurred more often after FCM than FDI. We also incorporated recent quality of life data from a clinical study, and calculated the number of infusions (and associated costs) of each iron formulation, that patients would require over five years. Clinical data were obtained from published medical literature, while cost data came from UK sources including the 2022/2023 National Tariff Payment System and the British National Formulary. Our model showed that FDI was associated with quality of life improvements, fewer overall infusions per treatment course, and reduced costs compared to FCM, from the English Department of Health and Social Care perspective, the societal perspective, and the perspective of individual healthcare providers (namely NHS Trusts) within NHS England. FDI is therefore likely to represent the best value intravenous iron for the treatment of IDA with IBD in the UK.
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Anemia Ferropriva , Anemia , Dissacarídeos , Hipofosfatemia , Doenças Inflamatórias Intestinais , Maltose/análogos & derivados , Humanos , Anemia Ferropriva/tratamento farmacológico , Anemia Ferropriva/etiologia , Qualidade de Vida , Análise Custo-Benefício , Compostos Férricos , Ferro , Inglaterra , Hipofosfatemia/complicações , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/tratamento farmacológicoRESUMO
BACKGROUND: The aim of this systematic review and meta-analysis is to assess the efficacy and safety of faecal microbiota transplantation [FMT] in the treatment of chronic pouchitis. METHODS: A PRISMA-compliant systematic review and meta-analysis was conducted using the following databases and clinical trial registers: Medline, Embase, Scopus, Cochrane Database of Systematic Reviews [CENTRAL], clinical trials.gov, ScienceDirect, and VHL [virtual health library]. The primary outcome was clinical response/remission in patients treated with FMT. Secondary outcomes included safety profile, quality of life, and changes in the gut microbiome. RESULTS: Seven observational cohort studies/case series and two randomised, controlled trials with a total of 103 patients were included. The route, preparation, and quantity of FMT administered varied among the included studies. Clinical response rate of 42.6% with a remission rate of 29.8% was estimated in our cohort following FMT therapy. Minor, self-limiting, adverse events were reported, and the treatment was well tolerated with good short- and long-term safety profiles. Successful FMT engraftment in recipients varied and, on average, microbial richness and diversity was lower in patients with pouchitis. In some instances, shifts with specific changes towards abundance of species, suggestive of a 'healthier' pouch microbiota, were observed following treatment with FMT. CONCLUSION: The evidence for FMT in the treatment of chronic pouchitis is sparse, which limits any recommendations being made for its use in clinical practice. Current evidence from low-quality studies suggests a variable clinical response and remission rate, but the treatment is well tolerated, with a good safety profile. This review emphasises the need for rationally designed, well-powered, randomised, placebo-controlled trials to understand the efficacy of FMT for the treatment of pouchitis.
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Microbioma Gastrointestinal , Pouchite , Humanos , Transplante de Microbiota Fecal/efeitos adversos , Pouchite/terapia , Pouchite/etiologia , Qualidade de Vida , Indução de Remissão , Resultado do Tratamento , Fezes , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
The gut microbiota is a reservoir for antimicrobial resistance genes (ARGs). With current sequencing methods, it is difficult to assign ARGs to their microbial hosts, particularly if these ARGs are located on plasmids. Metagenomic chromosome conformation capture approaches (meta3C and Hi-C) have recently been developed to link bacterial genes to phylogenetic markers, thus potentially allowing the assignment of ARGs to their hosts on a microbiome-wide scale. Here, we generated a meta3C dataset of a human stool sample and used previously published meta3C and Hi-C datasets to investigate bacterial hosts of ARGs in the human gut microbiome. Sequence reads mapping to repetitive elements were found to cause problematic noise in, and may importantly skew interpretation of, meta3C and Hi-C data. We provide a strategy to improve the signal-to-noise ratio by discarding reads that map to insertion sequence elements and to the end of contigs. We also show the importance of using spike-in controls to quantify whether the cross-linking step in meta3C and Hi-C protocols has been successful. After filtering to remove artefactual links, 87 ARGs were assigned to their bacterial hosts across all datasets, including 27 ARGs in the meta3C dataset we generated. We show that commensal gut bacteria are an important reservoir for ARGs, with genes coding for aminoglycoside and tetracycline resistance being widespread in anaerobic commensals of the human gut.
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Antibacterianos , Genes Bacterianos , Humanos , Antibacterianos/farmacologia , Filogenia , Bactérias , Resistência Microbiana a Medicamentos/genética , CromossomosRESUMO
BACKGROUND: Several randomised clinical trials (RCTs) performing faecal microbiota transplantation (FMT) for the management of inflammatory bowel disease (IBD), particularly for ulcerative colitis, have recently been published, but with major variations in study design. These include differences in administered dose, route and frequency of delivery, type of placebo and evaluated endpoints. Although the overall outcomes appear to be promising, they are highly dependent on both donor and recipient factors. OBJECTIVE: To develop concensus-based statements and recommendations for the evaluation, management and potential treatment of IBD using FMT in order to move towards standardised practices. DESIGN: An international panel of experts convened several times to generate evidence-based guidelines by performing a deep evaluation of currently available and/or published data. Twenty-five experts in IBD, immunology and microbiology collaborated in different working groups to provide statements on the following key issues related to FMT in IBD: (A) pathogenesis and rationale, (B) donor selection and biobanking, (C) FMT practices and (D) consideration of future studies and perspectives. Statements were evaluated and voted on by all members using an electronic Delphi process, culminating in a plenary consensus conference and generation of proposed guidelines. RESULTS AND CONCLUSIONS: Our group has provided specific statements and recommendations, based on best available evidence, with the end goal of providing guidance and general criteria required to promote FMT as a recognised strategy for the treatment of IBD.
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Colite Ulcerativa , Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Humanos , Transplante de Microbiota Fecal/métodos , Cidade de Roma , Doenças Inflamatórias Intestinais/terapia , Doenças Inflamatórias Intestinais/microbiologia , Colite Ulcerativa/terapia , Resultado do TratamentoRESUMO
Background and Aim: To evaluate the demographic and prognostic significance of gastrointestinal (GI) symptoms in patients with coronavirus disease 2019 (COVID-19). Methods: A systematic search of electronic information sources was conducted. Combined overall effect sizes were calculated using random-effects models for baseline demographic factors and outcomes including mortality, intensive care unit (ICU) admission, and length of hospital stay. Results: Twenty-four comparative observational studies reporting a total of 51 522 COVID-19 patients with (n = 6544) or without (n = 44 978) GI symptoms were identified. The patients with GI symptoms were of comparable age (mean difference [MD]: 0.25, 95% confidence interval [CI] -2.42 to 2.92, P = 0.86), rate of pre-existing hypertension (odds ratio [OR]: 1.11, 95% CI 0.86-1.42, P = 0.42), diabetes mellitus (OR: 1.14, 95% CI 0.91-1.44, P = 0.26), and coronary artery disease (OR: 1.00, 95% CI 0.86-1.16, P = 0.98) compared with those without GI symptoms. However, there were significantly more male patients in the GI symptoms group (OR: 0.85, 95% CI 0.75-0.95, P = 0.005). The presence of GI symptoms was associated with similar risk of mortality (OR: 0.73; 95% CI 0.47-1.13, P = 0.16), ICU admission (OR: 1.15; 95% CI 0.67-1.96, P = 0.62), and length of hospital stay (MD: 0.43; 95% CI -0.73 to 1.60, P = 0.47) when compared with their absence. Conclusion: Meta-analysis of the best possible available evidence demonstrated that GI symptoms in COVID-19 patients do not seem to affect patients with any specific demographic patterns and may not have any important prognostic significance. Although no randomized studies can be conducted on this topic, future high-quality studies can provide stronger evidence to further understand the impact of GI symptoms on outcomes of COVID-19 patients.
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Clostridioides difficile , Transplante de Microbiota Fecal , Fezes , Humanos , Monkeypox virusRESUMO
Autoimmune diseases have long been known to share a common pathogenesis involving a dysregulated immune system with a failure to recognize self from non-self-antigens. This immune dysregulation is now increasingly understood to be induced by environmental triggers in genetically predisposed individuals. Although several external environmental triggers have been defined in different autoimmune diseases, much attention is being paid to the role of the internal micro-environment occupied by the microbiome, which was once termed "the forgotten organ." In this regard, the gut microbiome, serving as an intermediary between some of those external environmental effectors and the immune system, helps programming of the immune system to be tolerant to innocent external and self-antigens. However, in the presence of perturbed gut microbiota (dysbiosis), the immune system could be erroneously directed in favor of pro-inflammatory pathways to instigate different autoimmune processes. An accumulating body of evidence, including both experimental and human studies (observational and interventional), points to the role of the gut microbiome in different autoimmune diseases. Such evidence could provide a rationale for gut microbiome manipulation with therapeutic and even preventative intent in patients with established or predisposed to autoimmune diseases, respectively. Perturbations of the gut microbiome have been delineated in some immune mediated diseases, IBD in particular. However, such patterns of disturbance (microbiome signatures) and related pathogenetic roles of the gut microbiome are context dependent and cannot be generalized in the same exact way to other autoimmune disorders, and the contribution of the gut microbiome to different disease phenotypes has to be precisely defined. In this review, we revise the evidence for a role of the gut microbiome in various autoimmune diseases and possible mechanisms mediating such a role.
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Doenças Autoimunes , Microbioma Gastrointestinal , Microbiota , Disbiose , Humanos , Sistema ImunitárioRESUMO
BACKGROUND: Faecal microbiota transplantation (FMT) has previously been explored as a treatment for ulcerative colitis (UC) however, biomarkers that predict and / or are associated with clinical response are poorly defined. The aim of this systematic review was to identify donor and recipient clinical, microbial and metabolomic predictive biomarkers of response to FMT in UC. METHODS: A systematic search of the relevant literature of studies exploring FMT in UC was conducted. Data on microbial diversity, taxonomic changes, metabolic changes, donor and recipient microbiota relationship and baseline predictors was examined. FINDINGS: 2852 studies were screened, and 25 papers were included in this systematic review. Following FMT, alpha diversity was seen to increase in responders along with increases in the abundance of Clostridiales clusters (order) and Bacteroides genus. Metabolomic analysis revealed short chain fatty acid (SCFA) production as a marker of FMT success. Donors or FMT batches with higher microbial alpha diversity and a greater abundance of taxa belonging to certain Bacteroides and Clostridia clusters were associated with clinical response to FMT. Baseline clinical predictors of response in patients with UC included younger age, less severe disease and possibly shorter disease duration. Baseline recipient microbial predictors at response consisted of higher faecal species richness, greater abundance of Candida and donor microbial profile similarity. INTERPRETATION: Distinct changes in gut microbiota profiles post-FMT indicate that certain baseline characteristics along with specific microbial and metabolomic alterations may predispose patients towards a successful therapeutic outcome. Opportunities towards a biomarker led precision medicine approach with FMT should be explored in future clinical studies. FUNDING: There no specific funding to declare.
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Colite Ulcerativa , Microbioma Gastrointestinal , Biomarcadores , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/etiologia , Colite Ulcerativa/terapia , Transplante de Microbiota Fecal/efeitos adversos , Fezes , Humanos , Resultado do TratamentoRESUMO
BACKGROUND: Faecal microbiota transplantation (FMT) is an emerging treatment modality, but its current clinical use and organisation are unknown. We aimed to describe the clinical use, conduct, and potential for FMT in Europe. METHODS: We invited all hospital-based FMT centres within the European Council member states to answer a web-based questionnaire covering their clinical activities, organisation, and regulation of FMT in 2019. Responders were identified from trials registered at clinicaltrials.gov and from the United European Gastroenterology (UEG) working group for stool banking and FMT. FINDINGS: In 2019, 31 FMT centres from 17 countries reported a total of 1,874 (median 25, quartile 10-64) FMT procedures; 1,077 (57%) with Clostridioides difficile infection (CDI) as indication, 791 (42%) with experimental indications, and 6 (0â¢3%) unaccounted for. Adjusted to population size, 0â¢257 per 100,000 population received FMT for CDI and 0â¢189 per 100,000 population for experimental indications. With estimated 12,400 (6,100-28,500) annual cases of multiple, recurrent CDI and indication for FMT in Europe, the current European FMT activity covers approximately 10% of the patients with indication. The participating centres demonstrated high safety standards and adherence to international consensus guidelines. Formal or informal regulation from health authorities was present at 21 (68%) centres. INTERPRETATION: FMT is a widespread routine treatment for multiple, recurrent CDI and an experimental treatment. Embedded within hospital settings, FMT centres operate with high standards across Europe to provide safe FMT. A significant gap in FMT coverage suggests the need to raise clinical awareness and increase the FMT activity in Europe by at least 10-fold to meet the true, indicated need. FUNDING: NordForsk under the Nordic Council and Innovation Fund Denmark (j.no. 8056-00006B).
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Laboratórios , Microbiota , Criança , Sequenciamento de Nucleotídeos em Larga Escala , HumanosAssuntos
COVID-19 , Colite Ulcerativa , Transplante de Microbiota Fecal , Fezes , Humanos , Reino Unido/epidemiologiaRESUMO
The mucosal surfaces of the body are characterised by complex, specialised microbial communities, often referred to as the microbiome. However, only much more recently-with the development of technologies allowing exploration of the composition and functionality of these communities-has meaningful research in this area become feasible. Over the past few years, there has been rapid growth in interest in the gut microbiome in particular, and its potential contribution to gastrointestinal and liver disease. This interest has already extended beyond clinicians to pharmaceutical companies, medical regulators and other stakeholders, and is high profile among patients and the lay public in general. Such expansion of knowledge holds the intriguing potential for translation into novel diagnostics and therapeutics; however, being such a nascent field, there remain many uncertainties, unanswered questions and areas of debate.