[Analysis of the relationship between intestinal segmented filamentous bacteria and rotavirus infection in children].

Objective: To investigate the association between intestinal colonization of segmented filamentous bacteria (SFB) and the risk of rotavirus infection, and the possible mechanisms by which SFB resist rotavirus infection. Methods: This case-control study enrolled 50 children aged 0 to 5 years who present to the outpatient Department of Children's Hospital, Zhejiang University School of Medicine with diarrhea and positive stool tests for rotavirus. The children were divided into rotavirus enteritis group and control group consisting of 55 children with non-gastrointestinal and non-infectious surgical diseases.The age and sex composition of the two groups was matched. The DNA of the fecal flora was extracted and SFB was detected by real-time fluorescence quantitative PCR analysis. The children in the rotavirus enteritis group and the control group were subgrouped by age and sex to analyze the differences in SFB positivity rates between different groups, and further compare and analyze the differences in SFB positivity rates between these two groups of children in the ≤2 years old subgroup and the >2-5 years old subgroup. Neutralization test was performed with p3340 protein and rotavirus to determine the relationship between rotavirus infection rate and p3340 concentration in Vero cells. χ2 test or Fisher's exact probability method was used for comparison between the two groups. Results: There were 50 children in the rotavirus enteritis group with an age of (1.7±0.9) years, and 55 children in the control group with an age of (1.8±1.1) years. The positive rate of SFB in children with rotavirus enteritis showed a declining trend across ages groups, with the highest rate of 10/14 in the ≤1 year old group, followed by 67% (14/21) in the >1-2 years old group, 9/15 in the >2-5 years old group, and there was no statistically significant difference (P=0.867). The positive rate of SFB in the control group was 12/15 in the ≤1 year old group, 95% (19/20) in the >1-2 years old group, 50% (10/20) in the >2-5 years old group, with statistical significance (P=0.004). The positive rate of SFB in children with rotavirus enteritis was 74% (20/27) in males and 56% (13/23) in females (χ2=1.71, P=0.192). In the control group, it was 79% (22/28) in males and 70% (19/27) in females (χ2=0.49, P=0.485). The positive rate of SFB was 66% (33/50) in the rotavirus enteritis group and 75% (41/55) in the control group, with no statistically significant (χ2=0.56, P=0.454). In the children ≤2 years old, the SFB positivity rate was 69% (24/35) in the rotavirus enteritis group and 89% (31/35) in the control group, with a statistically significant difference (χ2=4.16, P=0.041). However, in the children >2-5 years old, no statistically significant difference was observed, with the positive rate of SFB being 9/15 in the rotavirus enteritis group and 50% (10/20) in the control group (P=0.734). Pearson correlation analysis revealed a negative correlation between rotavirus infection and SFB positivity (r=-0.87,P<0.001). As the concentration of the p3340 specific protein increased, the luminescence intensity of the luciferase in the Vero cells, which were suitable for cultivating rotavirus, exhibited a decreasing trend (F=4.17, P=0.001). Conclusions: SFB colonization in infants less than 2 years old is associated with a reduced risk of rotavirus infection. Cloning of specific SFB functional protein p3340 neutralizes rotavirus infection of Vero cells, and this mechanism of targeting rotavirus infection differs from the common antiviral mechanism.

Investigation of potentially pathogenic Vibrionaceae in Saint-Louis city, Senegal.

Introduction: as cholera, due to toxigenic bacteria Vibrio cholera (serogroups O1 and O139), is a major public health threat in Africa, the aim of this work was to investigate potentially pathogenic Vibrionaceae bacteria firstly from human stool samples, and secondly from various environmental water points of Saint-Louis city in Senegal. Methods: a hospital-based study was conducted between 2013 and 2015. Stool samples were taken and cultured from daily incoming patients or hospitalized for acute diarrhea at Saint-Louis´ regional hospital. For environment, a monthly longitudinal sampling from January to October 2016 was carried out at 10 sites in the city. We used total DNA extracted from APW (alkaline peptone water) broth solutions and on suspect bacterial colonies to run PCR Multiplex targeting specific DNA fragments to detect Vibrio genus and specific species. In case of positivity, a simplex PCR was performed to test for cholera toxins Ctx, and V. parahaemolyticus TRH and TDH. Results: for 43 patients screened, bacterial culture was positive in 6% of cases but no strain of V. cholerae or other Vibrio sp. was isolated. PCR on 90 APW solutions were positive for Vibrio sp.(n = 43), V. cholera(n = 27), V. mimicus(n = 16), V. parahaemolyticus(8), V. alginolyticus(n = 4), and V. vulnificus(n = 2). Unlike for those on suspected colonies which were positive for a majority of V. parahaemolyticus (n = 40) and V. cholerae non-O1 / O139 (n = 35). Six strains of V. parahaemolyticus carried TRH gene, 3 of which expressed simultaneously virulence TRH and TDH genes. For physicochemical parameters, all temperatures varied similarly according to a unimodal seasonality, as well as salinity. Conclusion: despite the presence of natural populations of Vibrionaceae, even toxigenic ones, was noted in water environment, along with favorable habitat conditions that could play a role in transmission of Vibriosis in the Saint Louis population, we did not isolate any of them from patients screened at the hospital.

Analysis of gut microecological characteristics and differences between children with biliary atresia and non-biliary atresia in infantile cholestasis.

Introduction: In infants with cholestasis, variations in the enterohepatic circulation of bile acids and the gut microbiota (GM) characteristics differ between those with biliary atresia (BA) and non-BA, prompting a differential analysis of their respective GM profiles. Methods: Using 16S rDNA gene sequencing to analyse the variance in GM composition among three groups: infants with BA (BA group, n=26), non-BA cholestasis (IC group, n=37), and healthy infants (control group, n=50). Additionally, correlation analysis was conducted between GM and liver function-related indicators. Results: Principal component analysis using Bray-Curtis distance measurement revealed a significant distinction between microbial samples in the IC group compared to the two other groups. IC-accumulated co-abundance groups exhibited positive correlations with aspartate aminotransferase, alanine aminotransferase, total bilirubin, direct bilirubin, and total bile acid serum levels. These correlations were notably reinforced upon the exclusion of microbial samples from children with BA. Conclusion: The varying "enterohepatic circulation" status of bile acids in children with BA and non-BA cholestasis contributes to distinct GM structures and functions. This divergence underscores the potential for targeted GM interventions tailored to the specific aetiologies of cholestasis.

Ad libitum feeding of silkworm larvae powder-containing diets specifically influences metabolism-related and short-chain fatty acid-producing gut bacteria in mice.

Silkworm (Bombyx mori) larvae are expected to be useful as an ingredient in entomophagy. They are full of nutrients, including indigestible proteins; however, there have been few studies on the effects of the consumption of the entire body of silkworms on the intestinal microflora. We prepared a customized diet containing silkworm larval powder (SLP), and investigated the effects of ad libitum feeding of the SLP diet on the intestinal microbiota and the amount of short-chain fatty acids (SCFAs) in mice. We found that the diversity of the cecal and fecal microbiota increased in the mice fed the SLP diet (SLP group), and that the composition of their intestinal microbiota differed from that of the control mice. Furthermore, a genus-level microbiota analysis showed that in the SLP group, the proportions of Alistipes, Lachnospiraceae A2, and RF39, which are associated with the prevention of obesity, were significantly increased, while the proportions of Helicobacter and Anaerotruncus, which are associated with obesity, were significantly decreased. Additionally, the level of butyrate was increased in the SLP group, and Clostridia UCG 014 and Lachnospiraceae FCS020 were found to be associated with the level of butyrate, one of the major SCFAs. These findings indicated that silkworm powder may be useful as an insect food that might also improve obesity.

Taxonomic and phenotypic analysis of bifidobacteria isolated from IBD patients as potential probiotic strains.

BACKGROUND: Inflammatory Bowel Diseases (IBD) are a major public health issue with unclear aetiology. Changes in the composition and functionality of the intestinal microbiota are associated with these pathologies, including the depletion of strict anaerobes such as Feacalibacterium prausnitzii. Less evidence is observed for depletion in other anaerobes, among which bifidobacteria. This study characterized the taxonomic and functional diversity of bifidobacteria isolated from the human intestinal microbiota in active and non-active IBD patients by a culturomics approach and evaluated if these bifidobacteria might be used as probiotics for gut health. RESULTS: A total of 341 bifidobacteria were isolated from the intestinal microbiota of IBD patients (52 Crohn's disease and 26 ulcerative colitis patients), with a high proportion of Bifidobacterium dentium strains (28% of isolated bifidobacteria). In ulcerative colitis, the major species identified was B. dentium (39% of isolated bifidobacteria), in active and non-active ulcerative colitis. In Crohn's disease, B. adolescentis was the major species isolated from non-active patients (40%), while similar amounts of B. dentium and B. adolescentis were found in active Crohn's disease patients. The relative abundance of B. dentium was increased with age, both in Crohn's disease and ulcerative colitis and active and non-active IBD patients. Antibacterial capacities of bifidobacteria isolated from non-active ulcerative colitis against Escherichia coli LF82 and Salmonella enterica ATCC 14028 were observed more often compared to strains isolated from active ulcerative colitis. Finally, B. longum were retained as strains with the highest probiotic potential as they were the major strains presenting exopolysaccharide synthesis, antibacterial activity, and anti-inflammatory capacities. Antimicrobial activity and EPS synthesis were further correlated to the presence of antimicrobial and EPS gene clusters by in silico analysis. CONCLUSIONS: Different bifidobacterial taxonomic profiles were identified in the microbiota of IBD patients. The most abundant species were B. dentium, mainly associated to the microbiota of ulcerative colitis patients and B. adolescentis, in the intestinal microbiota of Crohn's disease patients. Additionally, the relative abundance of B. dentium significantly increased with age. Furthermore, this study evidenced that bifidobacteria with probiotic potential (antipathogenic activity, exopolysaccharide production and anti-inflammatory activity), especially B. longum strains, can be isolated from the intestinal microbiota of both active and non-active Crohn's disease and ulcerative colitis patients.

Faecalibaterium prausnitzii strain EXL01 boosts efficacy of immune checkpoint inhibitors.

Gut microbiota impacts responses to immune checkpoint inhibitors (ICI). A high level of Faecalibacterium prausnitzii have been associated with a positive response to ICI in multiple cancer types. Here, based on fecal shotgun metagenomics data, we show in two independent cohorts of patients with non-small cell lung cancer and advanced melanoma that a high level of F. prausnitzii at baseline is positively associated with a better clinical response to ICI. In MCA205 tumor-bearing mice, administration of F. prausnitzii strain EXL01, already in clinical development for Inflammatory Bowel Disease, restores the anti-tumor response to ICI in the context of antibiotic-induced microbiota perturbation at clinical and tumor transcriptomics level. In vitro, EXL01 strain enhances T cell activation in the presence of ICI. Interestingly, oral administration of EXL01 strain did not induce any change in fecal microbiota diversity or composition, suggesting a direct effect on immune cells in the small intestine. F. prausnitzii strain EXL01 will be evaluated as an adjuvant to ICI in multiple cancers in the near future.

Host specificity and zoonotic Enterocytozoon bieneusi genotypes in wild rodents from the Inner Mongolian Autonomous Region and Liaoning Province of China.

Introduction: Wild rodents can serve as reservoirs or carriers of E. bieneusi, thereby enabling parasite transmission to domestic animals and humans. This study aimed to investigate the prevalence of E. bieneusi in wild rodents from the Inner Mongolian Autonomous Region and Liaoning Province of China. Moreover, to evaluate the potential for zoonotic transmission at the genotype level, a genetic analysis of the isolates was performed. Methods: A total of 486 wild rodents were captured from two provinces in China. Polymerase chain reaction (PCR) was performed to amplify the vertebrate cytochrome b (cytb) gene in the fecal DNA of the rodents to detect their species. The genotype of E. bieneusi was determined via PCR amplification of the internal transcribed spacer (ITS) region of rDNA. The examination of genetic characteristics and zoonotic potential requires the application of similarity and phylogenetic analysis. Results: The infection rates of E. bieneusi in the four identified rodent species were 5.2% for Apodemus agrarius (n = 89), 4.5% for Cricetulus barabensis (n = 96), 11.3% for Mus musculus (n = 106), and 38.5% for Rattus norvegicus (n = 195). Infection was detected at an average rate of 17.4% among 486 rodents. Of the 11 identified genotypes, nine were known: SHR1 (detected in 32 samples), D (30 samples), EbpA (9 samples), PigEbITS7 (8 samples), HNR-IV (6 samples), Type IV (5 samples), HNR-VII (2 samples), HNH7 (1 sample), and HNPL-V (1 sample). Two novel genotypes were also discovered, NMR-I and NMR-II, each comprising one sample. The genotypes were classified into group 1 and group 13 via phylogenetic analysis. Discussion: Based on the initial report, E. bieneusi is highly prevalent and genetically diverse in wild rodents residing in the respective province and region. This indicates that these animals are crucial for the dissemination of E. bieneusi. Zoonotic E. bieneusi-carrying animals present a significant hazard to local inhabitants. Therefore, it is necessary to increase awareness regarding the dangers presented by these rodents and reduce their population to prevent environmental contamination.

Emerging importance of stool preservation methods in OMICS studies with special focus on cancer biology.

The intricate consortium of microorganisms in the human gut plays a crucial role in different physiological functions. The complex known-unknown elements of the gut microbiome are perplexing and the absence of standardized procedures for collecting and preserving samples has hindered continuous research in comprehending it. The technological bias produced because of lack of standard protocols has affected the reproducibility of results. The complex nature of diseases like colorectal cancer, gastric cancer, hepatocellular carcinoma and breast cancer require a thorough understanding of its etiology for an efficient and timely diagnosis. The designated protocols for collection and preservation of stool specimens have great variance, hence generate inconsistencies in OMICS studies. Due to the complications associated to the nature of sample, it is important to preserve the sample to be studied later in a laboratory or to be used in the future research purpose. Stool preservation is gaining importance due to the increased use of treatment options like fecal microbiota transplantation to cure conditions like recurrent Clostridium difficile infections and for OMICS studies including metagenomics, metabolomics and culturomics. This review provides an insight into the importance of omics studies for the identification and development of novel biomarkers for quick and noninvasive diagnosis of various diseases.

Multikingdom characterization of gut microbiota in patients with rheumatoid arthritis and rheumatoid arthritis-associated interstitial lung disease.

Rheumatoid arthritis-associated interstitial lung disease (RA-ILD) is a serious and common extra-articular disease manifestation. Patients with RA-ILD experience reduced bacterial diversity and gut bacteriome alterations. However, the gut mycobiome and virome in these patients have been largely neglected. In this study, we performed whole-metagenome shotgun sequencing on fecal samples from 30 patients with RA-ILD, and 30 with RA-non-ILD, and 40 matched healthy controls. The gut bacteriome and mycobiome were explored using a reference-based approach, while the gut virome was profiled based on a nonredundant viral operational taxonomic unit (vOTU) catalog. The results revealed significant alterations in the gut microbiomes of both RA-ILD and RA-non-ILD groups compared with healthy controls. These alterations encompassed changes in the relative abundances of 351 bacterial species, 65 fungal species, and 4,367 vOTUs. Bacteria such as Bifidobacterium longum, Dorea formicigenerans, and Collinsella aerofaciens were enriched in both patient groups. Ruminococcus gnavus (RA-ILD), Gemmiger formicilis, and Ruminococcus bromii (RA-non-ILD) were uniquely enriched. Conversely, Faecalibacterium prausnitzii, Bacteroides spp., and Roseburia inulinivorans showed depletion in both patient groups. Mycobiome analysis revealed depletion of certain fungi, including Saccharomyces cerevisiae and Candida albicans, in patients with RA compared with healthy subjects. Notably, gut virome alterations were characterized by an increase in Siphoviridae and a decrease in Myoviridae, Microviridae, and Autographiviridae in both patient groups. Hence, multikingdom gut microbial signatures showed promise as diagnostic indicators for both RA-ILD and RA-non-ILD. Overall, this study provides comprehensive insights into the fecal virome, bacteriome, and mycobiome landscapes of RA-ILD and RA-non-ILD gut microbiota, thereby offering potential biomarkers for further mechanistic and clinical research.

Pilot study assessing gut microbial diversity among sexual and gender minority young adults.

Evidence supports that people identifying as a sexual or gender minority (SGMs) experience minority-related stress resulting from discrimination or expectations of prejudice, and that this is associated with increased mental and physical health problems compared to cisgender heterosexuals. However, the biological mechanisms driving minority-related stress impacts remain unknown, including the role of the gut microbiome. Thus, the aim of this study was to determine the relationship between SGM status and gut microbiome health among young adults attending a 4-year university. To this end, a prospective pilot study was completed in the fall and spring semesters of 2021-22. Self-identified SGMs (N = 22) and cisgender-heterosexuals (CIS-HET, N = 43) completed in-person interviews to provide mental health data and demographic information. Nail and saliva samples were collected at the time of interview to quantify chronic and acute cortisol. Stool samples were collected within 48 hours of interview for microbiome analysis. Assessment of the gut microbiota identified a significant reduction in alpha diversity among the SGM group, even when adjusting for mental health outcome. SGM group showed trends for higher abundance of microbes in phylum Bacteroidetes and lower abundance of microbes in phyla Firmicutes, Actinobacteria, and Proteobacteria compared to the CIS-HET group. These findings support that the gut microbiome could be contributing to negative health effects among the SGM community.

Occurrence and genotyping of Enterocytozoon bieneusi in flying squirrels (Trogopterus xanthipes) from China.

Enterocytozoon bieneusi is an obligate intracellular microsporidian parasite with a worldwide distribution. As a zoonotic pathogen, E. bieneusi can infect a wide range of wildlife hosts through the fecal-oral route. Although the feces of flying squirrels (Trogopterus xanthipes) are considered a traditional Chinese medicine (as "faeces trogopterori"), no literature is available on E. bieneusi infection in flying squirrels to date. In this study, a total of 340 fresh flying squirrel fecal specimens from two captive populations were collected in Pingdingshan city, China, to detect the prevalence of E. bieneusi and assess their zoonotic potential. By nested PCR amplification of the ITS gene, six specimens tested positive, with positive samples from each farm, with an overall low infection rate of 1.8%. The ITS sequences revealed three genotypes, including known genotype D and two novel genotypes, HNFS01 and HNFS02. Genotype HNFS01 was the most prevalent (4/6, 66.7%). Phylogenetic analysis showed that all genotypes clustered into zoonotic Group 1, with the novel genotypes clustering into different subgroups. To our knowledge, this is the first report of E. bieneusi infection in flying squirrels, suggesting that flying squirrels could act as a potential reservoir and zoonotic threat for E. bieneusi transmission to humans in China.

Title: Occurrence et génotypage d'Enterocytozoon bieneusi chez les écureuils volants (Trogopterus xanthipes) de Chine. Abstract: Enterocytozoon bieneusi est un parasite microsporidien intracellulaire obligatoire présent dans le monde entier. En tant qu'agent pathogène zoonotique, E. bieneusi peut infecter un large éventail d'hôtes sauvages par la voie fécale-orale. Bien que les excréments d'écureuils volants (Trogopterus xanthipes) soient considérés comme un ingrédient de médecine traditionnelle chinoise (comme « faeces trogopterori ¼), aucune littérature n'est disponible à ce jour sur l'infection par E. bieneusi chez les écureuils volants. Dans cette étude, un total de 340 spécimens fécaux frais d'écureuils volants provenant de deux populations captives ont été collectés dans la ville de Pingdingshan, en Chine, pour détecter la prévalence d'E. bieneusi et évaluer leur potentiel zoonotique. Par amplification PCR nichée du gène ITS, six échantillons se sont révélés positifs, avec des échantillons positifs dans chaque ferme, et un taux d'infection global faible, à 1,8 %. Les séquences ITS ont révélé trois génotypes, dont le génotype D connu et deux nouveaux génotypes, HNFS01 et HNFS02. Le génotype HNFS01 était le plus répandu (4/6, 66,7 %). L'analyse phylogénétique a montré que tous les génotypes se regroupaient dans le groupe zoonotique 1, les nouveaux génotypes se regroupant en différents sous-groupes. À notre connaissance, il s'agit du premier rapport d'infection par E. bieneusi chez des écureuils volants, ce qui suggère que les écureuils volants pourraient agir comme un réservoir potentiel et une menace zoonotique pour la transmission d'E. bieneusi aux humains en Chine.

Changes of composition and antibiotic resistance of fecal coliform bacteria in municipal wastewater treatment plant.

The dynamics of the composition and antibiotic resistance of the fecal coliform bacteria (FCB) in a typical wastewater treatment plant (WWTP) were investigated concerning the seasonal changes. Results showed that WWTP could remove the FCB concentration by 3∼5 logs within the effluent of 104∼105 CFU/L, but the antibiotic resistant rate of FCB species increased significantly after WWTP. The dominant FCB changed from Escherichia coli in the influent (∼73.0%) to Klebsiella pneumoniae in the effluent (∼53.3%) after WWTP, where the Escherichia coli was removed the most, while Klebsiella pneumoniae was the most persistent. The secondary tank removed the most of FCB (by 3∼4 logs) compared to other processes, but increased all the concerned antibiotic resistant rate. The potential super bugs of FCB community showing resistance to all the target antibiotics were selected in the biological treatment unit of WWTP. The FCB showed the highest multiple antibiotic resistance (92.9%) in total which even increased to 100% in the effluent. Klebsiella has the highest antibiotic resistant rate in FCB, with a multiple antibiotic resistance rate of 98.4%. These indicated that the Klebsiella pneumoniae not just Escherichia coli should be specially emphasized after WWTP concerning the health risk associated with FCB community.

Multicenter comparative study of Enterocytozoon bieneusi DNA extraction methods from stool samples, and mechanical pretreatment protocols evaluation.

Nowadays, the use of qPCR for the diagnosis of intestinal microsporidiosis is increasing. There are several studies on the evaluation of qPCR performance but very few focus on the stool pretreatment step before DNA extraction, which is nevertheless a crucial step. This study focuses on the mechanical pretreatment of stools for Enterocytozoon bieneusi spores DNA extraction. Firstly, a multicenter comparative study was conducted evaluating seven extraction methods (manual or automated) including various mechanical pretreatment. Secondly, several durations and grinding speeds and types of beads were tested in order to optimize mechanical pretreatment. Extraction methods of the various centers had widely-varying performances especially for samples with low microsporidia loads. Nuclisens® easyMAG (BioMérieux) and Quick DNA Fecal/Soil Microbe Microprep kit (ZymoResearch) presented the best performances (highest frequencies of detection of low spore concentrations and lowest Ct values). Optimal performances of mechanical pretreatment were obtained by applying a speed of 30 Hz during 60 s with the TissueLyser II (Qiagen) using commercial beads of various materials and sizes (from ZymoResearch or MP Biomedicals). Overall, the optimal DNA extraction method for E. bieneusi spores contained in stool samples was obtained with a strong but short bead beating using small-sized beads from various materials.

Lactiplantibacillus argentoratensis AGMB00912 alleviates salmonellosis and modulates gut microbiota in weaned piglets: a pilot study.

This study aimed to evaluate the efficacy of Lactiplantibacillus argentoratensis AGMB00912 (LA) in reducing Salmonella Typhimurium infection in weaned piglets. The investigation focused on the influence of LA on the gut microbiota composition, growth performance, and Salmonella fecal shedding. The results indicated that LA supplementation significantly improved average daily gain and reduced the prevalence and severity of diarrhea. Fecal analysis revealed reduced Salmonella shedding in the LA-supplemented group. Furthermore, LA notably altered the composition of the gut microbiota, increasing the levels of beneficial Bacillus and decreasing those of harmful Proteobacteria and Spirochaetes. Histopathological examination showed less intestinal damage in LA-treated piglets than in the controls. The study also observed that LA affected metabolic functions related to carbohydrate, amino acid, and fatty acid metabolism, thereby enhancing gut health and resilience against infection. Short-chain fatty acid concentrations in the feces were higher in the LA group, suggesting improved gut microbial activity. LA supplementation enriched the population of beneficial bacteria, including Streptococcus, Clostridium, and Bifidobacterium, while reducing the number of harmful bacteria, such as Escherichia and Campylobacter. These findings indicate the potential of LA as a probiotic alternative for swine nutrition, offering protective effects to the gut microbiota against Salmonella infection.

Improved Diagnosis and Treatment Monitoring of Tuberculosis Using Stool and the Tuberculosis Bacterial Load Assay (TB-MBLA).

The diagnosis and monitoring of tuberculosis treatment is difficult as many patients are unable to produce sputum. This means that many patients are treated on the basis of clinical findings and consequently some will be exposed to anti-tuberculosis drugs unnecessarily. Moreover, for those appropriately on treatment and unable to produce a sputum sample, it will be impossible to monitor the response to treatment. We have shown that stool is a potential alternative sample type for diagnosis of tuberculosis. Currently, available protocols like the Xpert MTB/RIF use DNA as a target to detect Mycobacterium tuberculosis in stool but DNA survives long after the organism is dead so it is not certain whether a positive test is from an old or a partially treated infection. The TB MBLA only detects live organisms and thus, can be used to follow the response to treatment. In this chapter, we describe a protocol for TB-MBLA, an RNA-based assay, and apply it to quantify TB bacteria in stool.

A powerful machine learning approach to identify interactions of differentially abundant gut microbial subsets in patients with metastatic and non-metastatic pancreatic cancer.

Pancreatic cancer has a dismal prognosis, as it is often diagnosed at stage IV of the disease and is characterized by metastatic spread. Gut microbiota and its metabolites have been suggested to influence the metastatic spread by modulating the host immune system or by promoting angiogenesis. To date, the gut microbial profiles of metastatic and non-metastatic patients need to be explored. Taking advantage of the 16S metagenomic sequencing and the PEnalized LOgistic Regression Analysis (PELORA) we identified clusters of bacteria with differential abundances between metastatic and non-metastatic patients. An overall increase in Gram-negative bacteria in metastatic patients compared to non-metastatic ones was identified using this method. Furthermore, to gain more insight into how gut microbes can predict metastases, a machine learning approach (iterative Random Forest) was performed. Iterative Random Forest analysis revealed which microorganisms were characterized by a different level of relative abundance between metastatic and non-metastatic patients and established a functional relationship between the relative abundance and the probability of having metastases. At the species level, the following bacteria were found to have the highest discriminatory power: Anaerostipes hadrus, Coprobacter secundus, Clostridium sp. 619, Roseburia inulinivorans, Porphyromonas and Odoribacter at the genus level, and Rhodospirillaceae, Clostridiaceae and Peptococcaceae at the family level. Finally, these data were intertwined with those from a metabolomics analysis on fecal samples of patients with or without metastasis to better understand the role of gut microbiota in the metastatic process. Artificial intelligence has been applied in different areas of the medical field. Translating its application in the field of gut microbiota analysis may help fully exploit the potential information contained in such a large amount of data aiming to open up new supportive areas of intervention in the management of cancer.

Comprehensive assessment of machine learning methods for diagnosing gastrointestinal diseases through whole metagenome sequencing data.

The gut microbiome, linked significantly to host diseases, offers potential for disease diagnosis through machine learning (ML) pipelines. These pipelines, crucial in modeling diseases using high-dimensional microbiome data, involve selecting profile modalities, data preprocessing techniques, and classification algorithms, each impacting the model accuracy and generalizability. Despite whole metagenome shotgun sequencing (WMS) gaining popularity for human gut microbiome profiling, a consensus on the optimal methods for ML pipelines in disease diagnosis using WMS data remains elusive. Addressing this gap, we comprehensively evaluated ML methods for diagnosing Crohn's disease and colorectal cancer, using 2,553 fecal WMS samples from 21 case-control studies. Our study uncovered crucial insights: gut-specific, species-level taxonomic features proved to be the most effective for profiling; batch correction was not consistently beneficial for model performance; compositional data transformations markedly improved the models; and while nonlinear ensemble classification algorithms typically offered superior performance, linear models with proper regularization were found to be more effective for diseases that are linearly separable based on microbiome data. An optimal ML pipeline, integrating the most effective methods, was validated for generalizability using holdout data. This research offers practical guidelines for constructing reliable disease diagnostic ML models with fecal WMS data.

Long-term effects of fecal microbiota transplantation on gut microbiota after Helicobacter pylori eradication with bismuth quadruple therapy: A randomized controlled trial.

BACKGROUND: Eradicating Helicobacter pylori infection by bismuth quadruple therapy (BQT) is effective. However, the effect of BQT and subsequent fecal microbiota transplant (FMT) on the gut microbiota is less known. MATERIALS AND METHODS: This prospective randomized controlled trial was conducted at a tertiary hospital in China from January 2019 to October 2020, with the primary endpoints the effect of BQT on the gut microbiota and the effect of FMT on the gut microbiota after bismuth quadruple therapy eradication therapy. A 14-day BQT with amoxicillin and clarithromycin was administered to H. pylori-positive subjects, and after eradication therapy, patients received a one-time FMT or placebo treatment. We then collected stool samples to assess the effects of 14-day BQT and FMT on the gut microbiota. 16 s rDNA and metagenomic sequencing were used to analyze the structure and function of intestinal flora. We also used Gastrointestinal Symptom Rating Scale (GSRS) to evaluate gastrointestinal symptom during treatment. RESULTS: A total of 30 patients were recruited and 15 were assigned to either FMT or placebo groups. After eradication therapy, alpha-diversity was decreased in both groups. At the phylum level, the abundance of Bacteroidetes and Firmicutes decreased, while Proteobacteria increased. At the genus level, the abundance of beneficial bacteria decreased, while pathogenic bacteria increased. Eradication therapy reduced some resistance genes abundance while increased the resistance genes abundance linked to Escherichia coli. While they all returned to baseline by Week 10. Besides, the difference was observed in Week 10 by the diarrhea score between two groups. Compared to Week 2, the GSRS total score and diarrhea score decreased in Week 3 only in FMT group. CONCLUSIONS: The balance of intestinal flora in patients can be considerably impacted by BQT in the short term, but it has reverted back to baseline by Week 10. FMT can alleviate gastrointestinal symptoms even if there was no evidence it promoted restoration of intestinal flora.

Dietary fiber induces a fat preference associated with the gut microbiota.

Eating behavior is essential to human health. However, whether future eating behavior is subjected to the conditioning of preceding dietary composition is unknown. This study aimed to investigate the effect of dietary fiber consumption on subsequent nutrient-specific food preferences between palatable high-fat and high-sugar diets and explore its correlation with the gut microbiota. C57BL/6NJcl male mice were subjected to a 2-week dietary intervention and fed either a control (n = 6) or inulin (n = 6) diet. Afterward, all mice were subjected to a 3-day eating behavioral test to self-select from the simultaneously presented high-fat and high-sugar diets. The test diet feed intakes were recorded, and the mice's fecal samples were analyzed to evaluate the gut microbiota composition. The inulin-conditioned mice exhibited a preference for the high-fat diet over the high-sugar diet, associated with distinct gut microbiota composition profiles between the inulin-conditioned and control mice. The gut microbiota Oscillospiraceae sp., Bacteroides acidifaciens, and Clostridiales sp. positively correlated with a preference for fat. Further studies with fecal microbiota transplantation and eating behavior-related neurotransmitter analyses are warranted to establish the causal role of gut microbiota on host food preferences. Food preferences induced by dietary intervention are a novel observation, and the gut microbiome may be associated with this preference.

Encapsulation protocol for fecal microbiota transplantation.

Introduction: Clostridioides difficile infections (CDI) continue to pose a challenge for clinicians. Fecal microbiota transplantation (FMT) is an effective treatment option in CDI. Furthermore, recent and ongoing studies suggest potential benefits of FMT in other diseases as well. Methods: We would like to present a novel protocol for encapsulation of lyophilized fecal material. Our method provides with better compliance as well as improved flexibility, storage and safety. Results: FMT was conducted in 28 patients with an overall success rate of 82,14% using apsules containing lyophilized stool. 16 of patients were given capsules with lessened bacteria counts. The success rate in this group was 93,75%. Discussion: The results highlight the still unanswered questions about the mechanism of action and contribute to a wider use of FMT in the clinical praxis and in research.