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1.
Gregor Gorkiewicz Gerhard G. Thallinger Slave Trajanoski Stefan Lackner Gernot Stocker Thomas Hinterleitner Christian Gülly Christoph H?genauer 《PloS one》2013,8(2)
Background & Aims
Diseases of the human gastrointestinal (GI) tract are often accompanied by diarrhea with profound alterations in the GI microbiota termed dysbiosis. Whether dysbiosis is due to the disease itself or to the accompanying diarrhea remains elusive. With this study we characterized the net effects of osmotic diarrhea on the composition of the GI microbiota in the absence of disease.Methods
We induced osmotic diarrhea in four healthy adults by oral administration of polyethylene glycol 4000 (PEG). Stool as well as mucosa specimens were collected before, during and after diarrhea and 16S rDNA-based microbial community profiling was used to assess the microbial community structure.Results
Stool and mucosal microbiotas were strikingly different, with Firmicutes dominating the mucosa and Bacteroidetes the stools. Osmotic diarrhea decreased phylotype richness and showed a strong tendency to equalize the otherwise individualized microbiotas on the mucosa. Moreover, diarrhea led to significant relative shifts in the phyla Bacteroidetes and Firmicutes and to a relative increase in the abundance of Proteobacteria on the mucosa, a phenomenon also noted in several inflammatory and diarrheal GI diseases.Conclusions
Changes in microbial community structure induced by osmotic diarrhea are profound and show similarities to changes observed in other GI diseases including IBD. These effects so must be considered when specimens from diarrheal diseases (i.e. obtained by stratification of samples according to diarrheal status) or conditions wherein bowel preparations like PEG (i.e. specimens obtained during endoscopy) are used. 相似文献2.
Seok?Jin?Kim Hyun?Ae?Jung Shih-Sung?Chuang Huangming?Hong Cheng-Cheng?Guo Junning?Cao Xiao-Nan?Hong Ritsuro?Suzuki Hye?Jin?Kang Jong?Ho?Won Wee-Joo?Chng Yok-Lam?Kwong Cheolwon?Suh Yu-Qin?Song Jun?Zhu Kevin?Tay Soon?Thye?Lim Junji?Suzumiya Tong-Yu?Lin
Background
The gastrointestinal (GI) tract is one of the most common extranasal sites in extranodal NK/T-cell lymphoma (ENKTL). However, data regarding ENKTL involving the GI tract are relatively scarce. Thus, we performed a multicenter, multinational retrospective study to analyze clinical features and treatment outcomes of ENKTL involving the GI tract.Patients and methods
Patients with ENKTL involving the GI tract diagnosed in twelve participating centers between 1991 and 2012 were retrospectively analyzed from five Asian countries.Results
The analysis of 81 patients with ENKTL involving the GI tract revealed that more than 60% of patients presented as advanced disease with B symptoms. 55 patients (68%) had GI manifestations including abdominal pain (n = 26, 32%), GI tract bleeding (n = 17, 21%) and bowel perforation (n = 12, 15%). The most common GI site was the small intestine, including the jejunum and ileum (n = 57, 70.3%). There were 34 patients (42%) who received systemic chemotherapy while 33 patients (41%) underwent surgery plus chemotherapy. However, 35 patients (43%) died due to disease progression, and treatment-related mortality including sepsis occurred in 17 patients (21%). Thus, the median overall survival was 7.8 months (95% Confidence interval: 3.9 – 11.7 months). Patients who could undergo surgery plus chemotherapy showed a trend of better survival than those treated with chemotherapy alone.Conclusion
Overall, the data indicated that ENKTL involving the GI tract has a dismal prognosis despite active treatment including chemotherapy and surgery. Thus, more effective treatment strategies are required for this disease entity.3.
ACC deaminase‐containing plant growth‐promoting rhizobacteria protect Papaver somniferum from downy mildew 下载免费PDF全文
N. Bharti A. Pandey T. Ray S. Singh C.S. Chanotiya A. Kalra 《Journal of applied microbiology》2017,122(5):1286-1298
Aims
Analysis of the stability and safety of Sulfolobus monocaudavirus 1 (SMV1) during passage through the mammalian GI tract.Methods and Results
A major challenge of using nano‐vectors to target gut microbiome is their survival during passage through the extremely acidic and proteolytic environment of the mammalian GI tract. Here, we investigated the thermo‐acidophilic archaeal virus SMV1 as a candidate therapeutic nano‐vector for the distal mammalian GI tract microbiome. We investigated the anatomical distribution, vector stability and immunogenicity of this virus following oral ingestion in mice and compared these traits to the more classically used Inovirus vector M13KE. We found that SMV1 particles were highly stable under both simulated GI tract conditions (in vitro) and in mice (in vivo). Moreover, SMV1 could not be detected in tissues outside the GI tract and it elicited a nearly undetectable inflammatory response. Finally, we used human intestinal organoids (HIOs) to show that labelled SMV1 did not invade or otherwise perturb the human GI tract epithelium.Conclusion
Sulfolobus monocaudavirus 1 appeared stable and safe during passage though the mammalian GI tract.Significance and Impact of the Study
This is the first study evaluating an archaeal virus as a potential therapeutic nanoparticle delivery system and it opens new possibilities for future development of novel nanoplatforms. 相似文献4.
Gabriella d’Ettorre Giancarlo Ceccarelli Noemi Giustini Sara Serafino Nina Calantone Gabriella De Girolamo Luigi Bianchi Valeria Bellelli Tommaso Ascoli-Bartoli Sonia Marcellini Ombretta Turriziani Jason M. Brenchley Vincenzo Vullo 《PloS one》2015,10(9)
Background
HIV infection results in damage to the gastrointestinal (GI) tract, microbial translocation and immune activation. These are not completely normalized with combined antiretroviral therapy (cART). Moreover, increate morbidity and mortality of cART-treated HIV-infected individuals is associated with inflammation.Methods
In order to enhance GI tract immunity, we recruited and treated 20 HIV-infected humans with cART supplemented with probiotics and followed inflammation and immunological parameters (clinical trial number NCT02164344). 11 HIV seronegative subjects were included as control group. The enumeration of CD4+, CD8+, CD38+ and HLA-DR+ lymphocytes were evaluated on peripheral blood; HIV-RNA levels, sCD14, d-dimer, C-reactive protein (CRP) high sensitivity C-reactive protein (hsCRP), IL-6 and Lipopolysaccharide Binding Protein (LBP) were assayed on plasma.Results
We observe that cART does not normalize the levels of immune activation in HIV positive patients anyway inflammation and markers of microbial translocation were significantly reduced with probiotic supplementation. Patients show a clear and statistically significant reduction in the levels of immune activation on CD4 T-lymphocytes, for both markers CD38 and HLA-DR and their simultaneous expression, LBP and hsCRP plasma levels after probiotic diet supplementation settling to values comparable to controls.Conclusions
Supplementing cART with probiotics in HIV-infected individuals may improve GI tract immunity and there by mitigate inflammatory sequelae, ultimately improving prognosis.Trial Registration
ClinicalTrials.gov NCT02164344 相似文献5.
Ian M. Carroll Tamar Ringel-Kulka Laurent Ferrier Michael C. Wu Jennica P. Siddle Lionel Bueno Yehuda Ringel 《PloS one》2013,8(10)
Objective
Intestinal proteases carry out a variety of functions in the gastrointestinal (GI) tract. Studies have reported that elevated enteric proteases in patients with GI disease can alter intestinal physiology, however the origin (human vs. microbial) of elevated proteases in patients with GI disease is unclear.Aim
The aim of this study was to investigate the association between protease activity and the microbiota in human fecal samples.Design
In order to capture a wide range of fecal protease (FP) activity stool samples were collected from 30 IBS patients and 24 healthy controls. The intestinal microbiota was characterized using 454 high throughput pyro-sequencing of the 16S rRNA gene. The composition and diversity of microbial communities were determined and compared using the Quantitative Insights Into Microbial Ecology (QIIME) pipeline. FP activity levels were determined using an ELISA-based method. FP activity was ranked and top and bottom quartiles (n=13 per quartile) were identified as having high and low FP activity, respectively.Results
The overall diversity of the intestinal microbiota displayed significant clustering separation (p = 0.001) between samples with high vs. low FP activity. The Lactobacillales, Lachnospiraceae, and Streptococcaceae groups were positively associated with FP activity across the entire study population, whilst the Ruminococcaceae family and an unclassified Coriobacteriales family were negatively associated with FP activity.Conclusions
These data demonstrate significant associations between specific intestinal bacterial groups and fecal protease activity and provide a basis for further causative studies investigating the role of enteric microbes and GI diseases. 相似文献6.
Lotta Krogius-Kurikka Anna Kassinen Lars Paulin Jukka Corander Harri M?kivuokko Jarno Tuimala Airi Palva 《BMC microbiology》2009,9(1):68
Background
The human gastrointestinal (GI) tract microbiota is characterised by an abundance of uncultured bacteria most often assigned in phyla Firmicutes and Bacteroidetes. Diversity of this microbiota, even though approached with culture independent techniques in several studies, still requires more elucidation. The main purpose of this work was to study whether the genomic percent guanine and cytosine (%G+C) -based profiling and fractioning prior to 16S rRNA gene sequence analysis reveal higher microbiota diversity, especially with high G+C bacteria suggested to be underrepresented in previous studies. 相似文献7.
Background and Aim
The largest source of melatonin, according to animal studies, is the gastrointestinal (GI) tract but this is not yet thoroughly characterized in humans. This study aims to map the expression of melatonin and its two receptors in human GI tract and pancreas using microarray analysis and immunohistochemistry.Method
Gene expression data from normal intestine and pancreas and inflamed colon tissue due to ulcerative colitis were analyzed for expression of enzymes relevant for serotonin and melatonin production and their receptors. Sections from paraffin-embedded normal tissue from 42 individuals, representing the different parts of the GI tract (n=39) and pancreas (n=3) were studied with immunohistochemistry using antibodies with specificity for melatonin, MT1 and MT2 receptors and serotonin.Results
Enzymes needed for production of melatonin are expressed in both GI tract and pancreas tissue. Strong melatonin immunoreactivity (IR) was seen in enterochromaffin (EC) cells partially co-localized with serotonin IR. Melatonin IR was also seen in pancreas islets. MT1 and MT2 IR were both found in the intestinal epithelium, in the submucosal and myenteric plexus, and in vessels in the GI tract as well as in pancreatic islets. MT1 and MT2 IR was strongest in the epithelium of the large intestine. In the other cell types, both MT2 gene expression and IR were generally elevated compared to MT1. Strong MT2, IR was noted in EC cells but not MT1 IR. Changes in gene expression that may result in reduced levels of melatonin were seen in relation to inflammation.Conclusion
Widespread gastroenteropancreatic expression of melatonin and its receptors in the GI tract and pancreas is in agreement with the multiple roles ascribed to melatonin, which include regulation of gastrointestinal motility, epithelial permeability as well as enteropancreatic cross-talk with plausible impact on metabolic control. 相似文献8.
Gary V. Martinez Suryakiran Navath Kamini Sewda Venkataramanarao Rao Parastou Foroutan Ramesh Alleti Valerie E. Moberg Ali M. Ahad Domenico Coppola Mark C. Lloyd Robert J. Gillies David L. Morse Eugene A. Mash 《Bioorganic & medicinal chemistry letters》2013,23(7):2061-2064
A scaffold bearing eight terminal alkyne groups was synthesized from sucrose, and copies of an azide-terminated Gd–DOTA complex were attached via copper(I)-catalyzed azide-alkyne cycloaddition. The resulting contrast agent (CA) was administered by gavage to C3H mice. Passage of the CA through the gastrointestinal (GI) tract was followed by T1-weighted magnetic resonance imaging (MRI) over a period of 47 h, by which time the CA had exited the GI tract. No evidence for leakage of the CA from the GI tract was observed. Thus, a new, orally administered CA for MRI of the GI tract has been developed and successfully demonstrated. 相似文献
9.
Xuesong He Yan Tian Lihong Guo Takashi Ano Renate Lux David R. Zusman Wenyuan Shi 《Microbial ecology》2010,60(3):665-676
The gastrointestinal (GI) tract is home to trillions of microbes. Within the same GI tract, substantial differences in the
bacterial species that inhabit the oral cavity and intestinal tract have been noted. While the influence of host environments
and nutritional availability in shaping different microbial communities is widely accepted, we hypothesize that the existing
microbial flora also plays a role in selecting the bacterial species that are being integrated into the community. In this
study, we used cultivable microbial communities isolated from different parts of the GI tract of mice (oral cavity and intestines)
as a model system to examine this hypothesis. Microbes from these two areas were harvested and cultured using the same nutritional
conditions, which led to two distinct microbial communities, each with about 20 different species as revealed by PCR-based
denaturing gradient gel electrophoresis analysis. In vitro community competition assays showed that the two microbial floras
exhibited antagonistic interactions toward each other. More interestingly, all the original isolates tested and their closely
related species displayed striking community preferences: They persisted when introduced into the bacterial community of the
same origin, while their viable count declined more than three orders of magnitude after 4 days of coincubation with the microbial
flora of foreign origin. These results suggest that an existing microbial community might impose a selective pressure on incoming
foreign bacterial species independent of host selection. The observed inter-flora interactions could contribute to the protective
effect of established microbial communities against the integration of foreign bacteria to maintain the stability of the existing
communities. 相似文献
10.
Background
Due to their role of receptors or transporters, membrane proteins play a key role in many important biological functions. In our work we used Grammatical Inference (GI) to localize transmembrane segments. Our GI process is based specifically on the inference of Even Linear Languages. 相似文献11.
12.
13.
Andrew Reed Jon C. Pigage Helen K. Pigage Cody Glickman Jeremy M. Bono 《Ecology and evolution》2019,9(23):13344-13358
Microbiota inhabiting the gastrointestinal (GI) tract of animals has important impacts on many host physiological processes. Although host diet is a major factor influencing the composition of the gut micro‐organismal community, few comparative studies have considered how differences in diet influence community composition across the length of the GI tract. We used 16S sequencing to compare the microbiota along the length of the GI tract in Abert's (Sciurus aberti) and fox squirrels (S. niger) living in the same habitat. While fox squirrels are generalist omnivores, the diet of Abert's squirrels is unusually high in plant fiber, particularly in winter when they extensively consume fiber‐rich inner bark of ponderosa pine (Pinus ponderosa). Consistent with previous studies, microbiota of the upper GI tract of both species consisted primarily of facultative anaerobes and was less diverse than that of the lower GI tract, which included mainly obligate anaerobes. While we found relatively little differentiation between the species in the microbiota of the upper GI tract, the community composition of the lower GI tract was clearly delineated. Notably, the Abert's squirrel lower GI community was more stable in composition and enriched for microbes that play a role in the degradation of plant fiber. In contrast, overall microbial diversity was higher in fox squirrels. We hypothesize that these disparities reflect differences in diet quality and diet breadth between the species. 相似文献
14.
Introduction
Although the safety of celecoxib has been investigated, limited data are available on complications affecting the entire (upper and lower) gastrointestinal (GI) tract, with no patient-level pooled analyses of upper and lower GI outcomes available. We therefore evaluated the upper and lower GI safety of celecoxib by using patient-level data from randomized controlled trials (RCTs).Methods
This patient-level pooled analysis included 52 prospective, randomized, double-blind parallel-group studies from the Celecoxib Clinical Database. Each study had a planned duration of continuous treatment with celecoxib or a nonselective nonsteroidal antiinflammatory drug (nsNSAID), rofecoxib, or the placebo comparator arm for at least 4 weeks. All studies with final reports completed by 1 October 2007 were included. The primary end point was the combined incidence of clinically significant upper and lower GI events (CSULGIEs). An independent blinded committee reviewed and adjudicated all end points by using predefined criteria and all available reported adverse events, laboratory data, and case narratives. All doses of celecoxib and all doses of all nsNSAIDs were pooled for analysis.Results
The pooled analysis involved 51,048 patients; 28,614 were randomized to celecoxib; 15,278 to nsNSAIDs (including 3,248 patients taking naproxen, 2,640 taking ibuprofen, 8,066 taking diclofenac, 1,234 taking loxoprofen, and 90 taking ketoprofen); 5,827 to placebo and 1,329 to rofecoxib. The mean age was 60 years, and 65% were women. Data on 1,042 patients with potential GI events were reviewed for end-points adjudication; the adjudication committee confirmed 89 patients with CSULGIEs. The majority were in the celecoxib and nsNSAID groups (with raw incidence proportions of 37 (0.1%) and 40 (0.3%), respectively). The incidence rates were 0.3, 0.9 and 0.3 per 100 patient-years in the celecoxib, nsNSAID, and placebo groups, respectively. The time to incidence of CSULGIEs was significantly longer with celecoxib than with nsNSAIDs (P = 0.0004).Conclusions
When compared with nsNSAIDs, celecoxib is associated with a significantly lower risk of all clinically significant GI events throughout the entire GI tract. This pooled analysis of 52 RCTs significantly advances the understanding of the upper and lower GI safety profile of celecoxib and its potential benefits to patients. 相似文献15.
H. Panwar N. Rokana S. V. Aparna J. Kaur A. Singh J. Singh K.S. Singh V. Chaudhary A.K. Puniya 《Journal of applied microbiology》2021,130(4):1035-1061
The human gastrointestinal (GI) tract has been bestowed with the most difficult task of protecting the underlying biological compartments from the resident commensal flora and the potential pathogens in transit through the GI tract. It has a unique environment in which several defence tactics are at play while maintaining homeostasis and health. The GI tract shows myriad number of environmental extremes, which includes pH variations, anaerobic conditions, nutrient limitations, elevated osmolarity etc., which puts a check to colonization and growth of nonfriendly microbial strains. The GI tract acts as a highly selective barrier/platform for ingested food and is the primary playground for balance between the resident and uninvited organisms. This review focuses on antimicrobial defense mechanisms of different sections of human GI tract. In addition, the protective mechanisms used by microbes to combat the human GI defence systems are also discussed. The ability to survive this innate defence mechanism determines the capability of probiotic or pathogen strains to confer health benefits or induce clinical events respectively. 相似文献
16.
Background
The first microbial genome sequence, Haemophilus influenzae, was published in 1995. Since then, more than 400 microbial genome sequences have been completed or commenced. This massive influx of data provides the opportunity to obtain biological insights through comparative genomics. However few tools are available for this scale of comparative analysis. 相似文献17.
Kristofer Andréasson Tore Saxne Agneta Scheja Izabela Bartosik Thomas Mandl Roger Hesselstrand 《Arthritis research & therapy》2014,16(1):R46
Introduction
Faecal calprotectin (FC) has been proposed to be a biomarker of gastrointestinal (GI) disease in systemic sclerosis (SSc). The purpose of this study was to extend cross-sectional observations and prospectively assess the variability of FC over time in SSc patients. We also aimed to examine FC in relation to immunosuppressive therapy. Finally we wanted to analyse FC in other rheumatic diseases to evaluate the specificity of FC for SSc GI disease.Methods
FC was measured in consecutive patients with SSc, primary Sjögren’s syndrome (pSS), rheumatoid arthritis (RA) and in healthy hospital workers. The intraindividual variability of FC in SSc was assessed with intra class correlation (ICC) and κ statistics. Associations between FC and objective markers of GI disease and immunosuppressive medication were investigated.Results
FC was associated with micronutrient deficiency and GI pathology as assessed by cineradiography confirming our previous results. FC showed only a limited intra-individual variation in SSc, ICC = 0.69 (95% confidence interval, CI: 0.57-0.78) and κ = 0.64 (95% CI: 0.56-0.73). Generalised immunosuppression did not have any significant impact on FC. FC was significantly higher in SSc patients compared to patients with pSS or RA as well as compared to healthy subjects.Conclusions
FC is a promising non-invasive biomarker for GI disease in SSc. In view of stable levels over time, FC could be a useful marker when novel, more specific drugs targeting the GI tract in SSc will be introduced. 相似文献18.
Evaluation of the bacterial diversity in the feces of cattle using 16S rDNA bacterial tag-encoded FLX amplicon pyrosequencing (bTEFAP) 总被引:1,自引:0,他引:1
Scot E Dowd Todd R Callaway Randall D Wolcott Yan Sun Trevor McKeehan Robert G Hagevoort Thomas S Edrington 《BMC microbiology》2008,8(1):125
Background
The microbiota of an animal's intestinal tract plays important roles in the animal's overall health, productivity and well-being. There is still a scarcity of information on the microbial diversity in the gut of livestock species such as cattle. The primary reason for this lack of data relates to the expense of methods needed to generate such data. Here we have utilized a bacterial tag-encoded FLX 16s rDNA amplicon pyrosequencing (bTEFAP) approach that is able to perform diversity analyses of gastrointestinal populations. bTEFAP is relatively inexpensive in terms of both time and labor due to the implementation of a novel tag priming method and an efficient bioinformatics pipeline. We have evaluated the microbiome from the feces of 20 commercial, lactating dairy cows. 相似文献19.
Jakub Fichna JodiAnne T. Wood Malvina Papanastasiou Subramanian K. Vadivel Piotr Oprocha Maciej Sa?aga Marta Sobczak Anna Mokrowiecka Adam I. Cygankiewicz Piotr K. Zakrzewski Ewa Ma?ecka-Panas Wanda M. Krajewska Piotr Ko?cielniak Alexandros Makriyannis Martin A. Storr 《PloS one》2013,8(12)
Aims
Irritable bowel syndrome (IBS) is a functional gastrointestinal (GI) disorder, associated with alterations of bowel function, abdominal pain and other symptoms related to the GI tract. Recently the endogenous cannabinoid system (ECS) was shown to be involved in the physiological and pathophysiological control of the GI function. The aim of this pilot study was to investigate whether IBS defining symptoms correlate with changes in endocannabinoids or cannabinoid like fatty acid levels in IBS patients.Methods
AEA, 2-AG, OEA and PEA plasma levels were determined in diarrhoea-predominant (IBS-D) and constipation-predominant (IBS-C) patients and were compared to healthy subjects, following the establishment of correlations between biolipid contents and disease symptoms. FAAH mRNA levels were evaluated in colonic biopsies from IBS-D and IBS-C patients and matched controls.Results
Patients with IBS-D had higher levels of 2AG and lower levels of OEA and PEA. In contrast, patients with IBS-C had higher levels of OEA. Multivariate analysis found that lower PEA levels are associated with cramping abdominal pain. FAAH mRNA levels were lower in patients with IBS-C.Conclusion
IBS subtypes and their symptoms show distinct alterations of endocannabinoid and endocannabinoid-like fatty acid levels. These changes may partially result from reduced FAAH expression. The here reported changes support the notion that the ECS is involved in the pathophysiology of IBS and the development of IBS symptoms. 相似文献20.
Jessica Schwarz Jasmine Burguet Olivier Rampin Gilles Fromentin Philippe Andrey Daniel Tomé Yves Maurin Nicolas Darcel 《PloS one》2010,5(2)