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1.
Pregnancy Hypertens ; 23: 211-219, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33530034

RESUMO

Preeclampsia is a pregnancy-specific disorder characterized by hypertension and dysfunction of several organs, that is associated with maternal and fetal complications. The human gut microbiota is related to health and disease including hypertension. Alterations in gut microbiota composition can change the short-chain fatty acid profile released by the bacteria and contribute to hypertension and metabolic syndrome. It is unclear if the composition of the gut microbiota is altered in women who develop late-onset preeclampsia. In this study, we investigated the composition of the gut microbiota at 28 weeks gestation in women who developed late-onset (>34 weeks gestation) preeclampsia (DPE) by 16S rRNA gene amplicon sequencing of fecal samples obtained from 213 pregnant women in the SPRING cohort (Study of Probiotics IN Gestational diabetes). Quantitative real-time PCR was used to assess the density of butyrate-producing genes. Gut microbiota composition was compared between women with and without DPE. The abundance of the butyrate-producing Coprococcus genus significantly decreased in DPE. Abundance of Coprococcus is significantly and positively correlated with the abundance of genes encoding the terminal step in bacterial butyrate formation (but and buk). Women with DPE also had significantly reduced levels of serum butyrate prior to the development of symptoms than controls. This study suggests that a reduction in the abundance of butyrate-producing bacteria, and Coprococcus spp. in particular, may contribute to an increased risk of developing preeclampsia in pregnant women.

2.
Head Neck ; 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33527579

RESUMO

BACKGROUND: Patients with oral cavity cancer (OCC) and oropharyngeal cancer (OPC) are often seen with locoregionally advanced disease requiring complex multimodality treatments. These treatments may have detrimental effects on the oral microbiome, which is critical to maintaining physiological balance and health. METHODS: The effects of different OCC and OPC treatment types on the oral microbiome and metabolomic profiles for 24-month post-treatment in patients with OCC and OPC were investigated using 16S rRNA gene amplicon next-generation sequencing and gas chromatography-mass spectrometry (GC-MS), respectively. RESULTS: Chemoradiation resulted in oral dysbiosis with specific depletion of genera which regulate the enterosalivary nitrate-nitrite-nitric oxide pathway. These data also correlate with the oral metabolomic profiles with nitric oxide-related precursor, modulator, or catalyst significantly downregulated in saliva samples from patients' postchemoradiation. CONCLUSIONS: Together, we have shown that oral dysbiosis due to the effects of chemoradiation could potentially have an impact on OCC and OPC patient's quality of life post-treatment.

3.
Nephrology (Carlton) ; 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33501716

RESUMO

BACKGROUND: There are few studies that have examined whether dysbiosis occurs in kidney donors and transplant recipients following kidney transplant surgery. AIM: To ascertain whether changes occur in the gastrointestinal microbiota of the kidney donor and recipient following kidney transplantation. METHODS: Kidney transplant recipients and their donors were prospectively enrolled in a pilot study to collect one faecal sample prior to, and another faecal sample between four to eight weeks following surgery. Gastrointestinal microbiota richness, Shannon diversity measures and functional assessments of kidney donors and recipients were analysed via metagenomic sequencing. RESULTS: The study included 12 donors (median age 56 years, 6 females) and 12 recipients (median age 51 years, 3 females). Donor microbiota showed no significant changes in gastrointestinal microbiota richness, Shannon diversity, or functional assessments before and after nephrectomy. Recipient microbiota was altered post-transplant, reflected in reductions of the mean (±SD) richness values (156 ± 46.5 to 116 ± 38.6, p = 0.002), and Shannon diversity (3.57 ± 0.49 to 3.14 ± 0.52, p = 0.007), and a dramatic increase in Roseburia spp. abundance post-transplant (26-fold increase from 0.16 ± 0.0091 to 4.6 ± 0.3; p = 0.006; FDR = 0.12). Functionally, the post-transplant microbial community shifted towards those taxa using the glycolysis pathway (1.2-fold increase; p = 0.02; FDR = 0.26) for energy metabolism, while those functions involved with reactive oxygen species degradation decreased (2.6-fold; p = 0.006; FDR = 0.14). CONCLUSION: Live donor kidney transplantation and standard care post-transplant result in significant alterations in gut microbiota richness, diversity, composition and functional parameters in kidney transplant recipients but not in their kidney donors.

4.
Ann Rheum Dis ; 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397732

RESUMO

OBJECTIVES: Analysis of oral dysbiosis in individuals sharing genetic and environmental risk factors with rheumatoid arthritis (RA) patients may illuminate how microbiota contribute to disease susceptibility. We studied the oral microbiota in a prospective cohort of patients with RA, first-degree relatives (FDR) and healthy controls (HC), then genomically and functionally characterised streptococcal species from each group to understand their potential contribution to RA development. METHODS: After DNA extraction from tongue swabs, targeted 16S rRNA gene sequencing and statistical analysis, we defined a microbial dysbiosis score based on an operational taxonomic unit signature of disease. After selective culture from swabs, we identified streptococci by sequencing. We examined the ability of streptococcal cell walls (SCW) from isolates to induce cytokines from splenocytes and arthritis in ZAP-70-mutant SKG mice. RESULTS: RA and FDR were more likely to have periodontitis symptoms. An oral microbial dysbiosis score discriminated RA and HC subjects and predicted similarity of FDR to RA. Streptococcaceae were major contributors to the score. We identified 10 out of 15 streptococcal isolates as S. parasalivarius sp. nov., a distinct sister species to S. salivarius. Tumour necrosis factor and interleukin 6 production in vitro differed in response to individual S. parasalivarius isolates, suggesting strain specific effects on innate immunity. Cytokine secretion was associated with the presence of proteins potentially involved in S. parasalivarius SCW synthesis. Systemic administration of SCW from RA and HC-associated S. parasalivarius strains induced similar chronic arthritis. CONCLUSIONS: Dysbiosis-associated periodontal inflammation and barrier dysfunction may permit arthritogenic insoluble pro-inflammatory pathogen-associated molecules, like SCW, to reach synovial tissue.

5.
J Clin Gastroenterol ; 55(1): 21-24, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33021560

RESUMO

Since the first fiberoptic instruments, gastrointestinal endoscopy has shaped the field of gastroenterology and is now a key diagnostic and therapeutic tool. Compared with the initial fiberoptic endoscopes state-of-the-art optical chips (or charge-coupled device technology) allowed a quantum leap in image quality. Despite these advances, gastrointestinal endoscopy is far from being perfect. The diagnostic yield (eg, for adenoma detection rates) is highly operator dependent and there is still the need for sedation or even anesthesia to address discomfort during the procedure. Despite highly standardized cleaning and high-level disinfection the reuse of contemporary (and difficult to clean) endoscopes with multiple channels exposes patients to the risk of transmission of infections. Artificial intelligence and pattern recognition should eliminate interindividual variability including polyp detection rates, self-propelled, and (potentially remotely controlled) scopes with a soft shaft could reduce the discomfort during procedures and abolish the need for sedation and anesthesia altogether and single-use designs should eliminate the risk of patient-to-patient transmission of infections. While these innovations are feasible and could be implemented rapidly utilizing available technology, they require a paradigm shift affecting all levels of the value chain from the supplier of the instruments to the end-users. Some may negate the need for a paradigm shift, but it is evident that a major redesign of the endoscopic equipment is overdue to fully utilize novel technologies and most importantly ensure the best possible outcomes for patients.

6.
Gastroenterology ; 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33011176

RESUMO

BACKGROUND & AIMS: Proteus spp, Gram-negative facultative anaerobic bacilli, have recently been associated with Crohn's disease (CD) recurrence after intestinal resection. We investigated the genomic and functional role of Proteus as a gut pathogen in CD. METHODS: Proteus spp abundance was assessed by ure gene-specific polymerase chain in 54 pairs of fecal samples and 101 intestinal biopsies from patients with CD and healthy controls. The adherence, invasion, and intracellular presence of 2 distinct isolates of Proteus mirabilis in epithelial cells were evaluated using immunofluorescence and electron microscopy. Intracellular gene expression profiles and regulated pathways were analyzed by RNA sequencing and KEGG pathway analysis. Biologic functions of 2 isolates of P mirabilis were determined by in vitro cell culture, and in vivo using conventional mice and germ-free mice. RESULTS: Proteus spp were significantly more prevalent and abundant in fecal samples and colonic tissue of patients with CD than controls. A greater abundance of the genus Fusobacterium and a lesser abundance of the genus Faecalibacterium were seen in patients with CD with a high Proteus spp abundance. All 24 Proteus monoclones isolated from patients with CD belonged to members of P mirabilis lineages and 2 isolates, recovered from stool or mucosa, were used in further studies. Mice gavaged with either P mirabilis strain had more severe colonic inflammation. Co-culture of the isolates with epithelial cell lines showed bacterial adherence, invasion, increased production of pro-inflammatory cytokines IL-18 and IL-1α, and cell necrosis. Both isolates induced key pro-inflammatory pathways, including NOD-like receptor signaling, Jak-STAT signaling, and MAPK signaling, and induced pro-inflammatory genes and activated inflammation-related pathways in gnotobiotic mice. CONCLUSIONS: P mirabilis in the gut is associated with CD and can induce inflammation in cells and animal models of colitis. P mirabilis can act as a pathobiont and play a crucial role in the pathogenesis of CD.

7.
Food Funct ; 11(9): 7892-7904, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32813756

RESUMO

Using in vitro fermentation conditions, this study investigated the fermentation characteristics of arabinoxylan (AX) and xyloglucan (XG) with a fecal inoculum that was collected either from humans consuming unrestricted diets or pigs fed a semi-defined diet with cellulose being the sole non-starch polysaccharide for 10 days prior to fecal collection. Metagenomic analysis revealed that microbial communities in the two types of inoculum were distinctively different, which led to distinct fermentation characteristics with the polysaccharides. The microbial communities fermented with the porcine fecal inoculum were clustered according to the fermentation time, while those fermented with the human fecal inoculum were differentiated by the substrates. Using the porcine fecal inoculum, irrespective of the substrates, Prevotella copri and the unclassified lineage rc4-4 were the dominant operational taxonomic units (OTUs) promoted during fermentation. Fermentation of wheat AX (WAX) and galacto-XG (GXG) with the human fecal inoculum, however, promoted different OTUs, except for a shared OTU belonging to Lachnospiraceae. Specifically, WAX promoted the growth of Bacteroides plebeius and a Blautia sp., while GXG promoted an unclassified Bacteroidales, Parabacteroides distasonis, Bacteroides uniformis and Bacteroides sp. 2. These changes in bacterial communities were in accordance with the short chain fatty acid (SCFA) production, where comparable SCFA profiles were obtained from the porcine fecal fermentation while different amounts and proportions of SCFA were acquired from fermentation of WAX and GXG with the human fecal inoculum. Altogether, this study indicated that the starting inoculum composition had a greater effect than polysaccharide chemistry in driving fermentation outcomes.

8.
Elife ; 92020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32720643

RESUMO

Inhibition of mTOR (mechanistic Target Of Rapamycin) signaling by rapamycin promotes healthspan and longevity more strongly in females than males, perhaps because inhibition of hepatic mTORC2 (mTOR Complex 2) specifically reduces the lifespan of males. Here, we demonstrate using gonadectomy that the sex-specific impact of reduced hepatic mTORC2 is not reversed by depletion of sex hormones. Intriguingly, we find that ovariectomy uncouples lifespan from metabolic health, with ovariectomized females having improved survival despite paradoxically having increased adiposity and decreased control of blood glucose levels. Further, ovariectomy unexpectedly promotes midlife survival of female mice lacking hepatic mTORC2, significantly increasing the survival of those mice that do not develop cancer. In addition to identifying a sex hormone-dependent role for hepatic mTORC2 in female longevity, our results demonstrate that metabolic health is not inextricably linked to lifespan in mammals, and highlight the importance of evaluating healthspan in mammalian longevity studies.

9.
Food Funct ; 11(6): 5635-5646, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32537617

RESUMO

A slower rate of starch digestion in the small intestine increases the amount of resistant starch (RS) entering the large intestine, which is associated with health benefits. Although increasing the amylose (AM) content of dietary starch intake is one way to increase RS, the processes involved in gut microbial hydrolysis and fermentation of high AM-RS substrates are poorly understood. In this study, five high AM wheat (HAW) starches ranging from 47% AM to 93% AM and a wild type (37% AM), in both native granular and cooked forms, were subjected to in vitro fermentation with a porcine faecal inoculum. Fermentation kinetics, temporal microbial changes, amylolytic enzyme activities and residual starch were determined. All granular starches showed similar fermentation characteristics, independent of AM level, whereas cooking accelerated fermentation of lower AM but slowed fermentation of high AM starches. HAW starches with a very high AM content (>85%) all had similar fermentation kinetics and short-chain fatty acid end-product profiles. Microbial α-amylase, ß-amylase, pullulanase and amyloglucosidase enzymatic activities were all detected and followed fermentation kinetics. HAW starch promoted shifts in the microbial community, with increases of the family Lachnospiraceae and the genus Treponema observed, while the genera Prevotella and Streptococcus were reduced in comparison to 37% AM. Overall, these findings suggest that any HAW starch incorporated into high RS food products would be expected to have beneficial microbiota-mediated effects in terms of fermentation kinetics and end products.

10.
Aliment Pharmacol Ther ; 52(1): 155-167, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32412673

RESUMO

BACKGROUND: Small intestinal bacterial overgrowth may play a role in gastrointestinal and non-gastrointestinal diseases. AIMS: To use quantitative polymerase chain reaction (qPCR) to determine and compare bacterial loads of duodenal biopsies in asymptomatic controls, and patients with functional gastrointestinal disorders (FGIDs) and inflammatory bowel disease (IBD) including ulcerative colitis (UC) and Crohn's disease (CD). To define effects of gastric acid inhibition on bacterial load, explore links of bacterial load and gastrointestinal symptoms in response to a standardised nutrient challenge and compare bacterial load with glucose breath test results. METHODS: In 237 patients (63 controls, 84 FGID and 90 IBD), we collected mucosal samples under aseptic conditions during endoscopy extracted and total DNA. Bacterial load metric was calculated utilising qPCR measurements of the bacterial 16S rRNA gene, normalised to human beta-actin expression. Standard glucose breath test and nutrient challenge test were performed. RESULTS: The duodenal microbial load was higher in patients with FGID (0.22 ± 0.03) than controls (0.07 ± 0.05; P = 0.007) and patients with UC (0.01 ± 0.05) or CD (0.02 ± 0.09), (P = 0.0001). While patients treated with proton pump inhibitors (PPI) had significantly higher bacterial loads than non-users (P < 0.05), this did not explain differences between patient groups and controls. Bacterial load was significantly (r = 0.21, P < 0.016) associated with the symptom response to standardised nutrient challenge test. Methane, but not hydrogen values on glucose breath test were associated with bacterial load measured utilising qPCR. CONCLUSIONS: Utilising qPCR, a diagnosis of FGID and treatment with PPI were independently associated with increased bacterial loads. Increased bacterial loads are associated with an augmented symptom response to a standardised nutrient challenge.


Assuntos
Duodeno/microbiologia , Gastroenteropatias/microbiologia , Doenças Inflamatórias Intestinais/microbiologia , Adulto , Idoso , Bactérias/genética , Bactérias/isolamento & purificação , Carga Bacteriana , Biópsia , Testes Respiratórios/métodos , Feminino , Gastroenteropatias/metabolismo , Glucose/metabolismo , Humanos , Doenças Inflamatórias Intestinais/metabolismo , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , RNA Ribossômico 16S/genética
11.
Biomolecules ; 10(5)2020 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-32429496

RESUMO

Esophageal adenocarcinoma (EAC) incidence has been rapidly increasing, potentially associated with the prevalence of the risk factors gastroesophageal reflux disease (GERD), obesity, high-fat diet (HFD), and the precursor condition Barrett's esophagus (BE). EAC development occurs over several years, with stepwise changes of the squamous esophageal epithelium, through cardiac metaplasia, to BE, and then EAC. To establish the roles of GERD and HFD in initiating BE, we developed a dietary intervention model in C57/BL6 mice using experimental HFD and GERD (0.2% deoxycholic acid, DCA, in drinking water), and then analyzed the gastroesophageal junction tissue lipidome and microbiome to reveal potential mechanisms. Chronic (9 months) HFD alone induced esophageal inflammation and metaplasia, the first steps in BE/EAC pathogenesis. While 0.2% deoxycholic acid (DCA) alone had no effect on esophageal morphology, it synergized with HFD to increase inflammation severity and metaplasia length, potentially via increased microbiome diversity. Furthermore, we identify a tissue lipid signature for inflammation and metaplasia, which is characterized by elevated very-long-chain ceramides and reduced lysophospholipids. In summary, we report a non-transgenic mouse model, and a tissue lipid signature for early BE. Validation of the lipid signature in human patient cohorts could pave the way for specific dietary strategies to reduce the risk of BE in high-risk individuals.

13.
Liver Int ; 40(6): 1356-1365, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32243703

RESUMO

BACKGROUND: Bile acids (BAs) are synthesized by the liver and modified by gut bacteria, and may play an intermediary role between the gut microbiome and liver in promoting fibrosis in non-alcoholic fatty liver disease (NAFLD). We investigated the associations between serum and faecal BAs, gut microbiome and fibrosis in patients with and without NAFLD and examined the impact of diet and alcohol consumption on these relationships. METHODS: Adult patients (n = 122) underwent liver biopsy and BAs characterization by high-performance liquid chromatography/mass spectrometry. Gut microbiome composition was analysed using next-generation 16S rRNA sequencing. Diet and alcohol intake were determined by 3-day food diary. RESULTS: Serum and faecal BA concentrations increased progressively among non-NAFLD controls (n = 55), NAFLD patients with no/mild fibrosis (F0-2, n = 58) and NAFLD with advanced fibrosis (F3/4, n = 9). Progressive increases in serum BAs were driven by primary conjugated BAs including glycocholic acid [GCA] and secondary conjugated BAs. In contrast, faecal BA increase was driven by secondary unconjugated BAs (predominately deoxycholic acid [DCA]). Serum GCA levels and faecal DCA levels correlated with the abundance of Bacteroidaceae and Lachnospiraceae, and stool secondary BAs with an unclassifiable family of the order Bacteroidales (Bacteroidales;other). These bacterial taxa were also associated with advanced fibrosis. Modest alcohol consumption was positively correlated with faecal DCA levels and relative abundance of Lachnospiracaea and Bacteroidales;other. CONCLUSIONS: Higher serum and faecal BA levels are associated with advanced fibrosis in NAFLD. Specific gut bacteria link alterations in BA profiles and advanced fibrosis, and may be influenced by low-level alcohol consumption.

14.
Am J Gastroenterol ; 115(6): 814-822, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32250997

RESUMO

Primary sclerosing cholangitis (PSC) is a rare, immune-mediated, chronic cholestatic liver disease associated with a unique phenotype of inflammatory bowel disease that frequently manifests as pancolitis with right-sided predominance. Available data suggest a bidirectional interplay of the gut-liver axis with critical roles for the gastrointestinal microbiome and circulating bile acids (BAs) in the pathophysiology of PSC. BAs shape the gut microbiome, whereas gut microbes have the potential to alter BAs, and there are emerging data that alterations of BAs and the microbiome are not simply a consequence but the cause of PSC. Clustering of PSC in families may suggest that PSC occurs in genetically susceptible individuals. After exposure to an environmental trigger (e.g., microbial byproducts or BAs), an aberrant or exaggerated cholangiocyte-induced immune cascade occurs, ultimately leading to bile duct damage and progressive fibrosis. The pathophysiology can be conceptualized as a triad of (1) gut dysbiosis, (2) altered BA metabolism, and (3) immune-mediated biliary injury. Immune activation seems to be central to the disease process, but immunosuppression does not improve clinical outcomes or alter the natural history of PSC. Currently, orthoptic liver transplantation is the only established life-saving treatment, whereas antimicrobial therapy or fecal transplantation is an emerging therapeutic option for PSC. The beneficial effects of these microbiome-based therapies are likely mediated by a shift of the gut microbiome with favorable effects on BA metabolism. In the future, personalized approaches will allow to better target the interdependence between microbiome, immune function, and BA metabolism and potentially cure patients with PSC.


Assuntos
Anti-Infecciosos/uso terapêutico , Ácidos e Sais Biliares/metabolismo , Colangite Esclerosante/terapia , Disbiose/terapia , Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais/microbiologia , Colangite Esclerosante/imunologia , Colangite Esclerosante/metabolismo , Colangite Esclerosante/microbiologia , Disbiose/imunologia , Disbiose/metabolismo , Transplante de Microbiota Fecal , Humanos , Imunidade nas Mucosas/imunologia , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Transplante de Fígado
15.
Int J Parasitol ; 50(3): 217-225, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32135180

RESUMO

Polyparasitism, involving soil-transmitted helminths. and Schistosoma blood flukes, is common in low to middle income countries. These helminths impact on the gut environment and can cause changes to the gut microbiome composition. Here we examined the gut microbiome in individuals with polyparasitism from two human cohorts in the Philippines utilising DNA sequencing-based profiling. Multiple helminth species infections were high with 70.3% of study participants harbouring at least two parasite species, and 16% harbouring at least five species. Increased numbers of helminth co-infections, in particular with the gut-resident soil-transmitted helminths, were significantly associated with increased bacterial diversity; however no significant parasite-gut microbiome associations were evident for individuals infected only with Schistosoma japonicum. In general, a healthy gut is associated with high bacterial diversity, which in these human cohorts may be the result of helminth-mediated immune modulation, or due to changes in the gut environment caused by these parasitic helminths.


Assuntos
Coinfecção , Microbioma Gastrointestinal/genética , Helmintíase/epidemiologia , Helmintos/isolamento & purificação , Esquistossomose/epidemiologia , Adolescente , Adulto , Albendazol/uso terapêutico , Ancylostoma/isolamento & purificação , Ancylostomatoidea/isolamento & purificação , Animais , Ascaris/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Criança , Pré-Escolar , Estudos de Coortes , Coinfecção/microbiologia , Coinfecção/parasitologia , Fezes/microbiologia , Fezes/parasitologia , Feminino , Genes Bacterianos , Helmintíase/tratamento farmacológico , Helmintos/genética , Interações Hospedeiro-Parasita , Humanos , Masculino , Metagenômica , Interações Microbianas , Pessoa de Meia-Idade , Patologia Molecular , Filipinas/epidemiologia , Schistosoma/isolamento & purificação , Esquistossomose/tratamento farmacológico , Solo/parasitologia , Trichuris/isolamento & purificação , Adulto Jovem
16.
Nutrients ; 12(3)2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32204474

RESUMO

(1) Background: The Food Agricultural Organization/World Health Organization (FAO/WHO) International Food Standards Codex Alimentarius CXS 192e International Food Standards (hereafter, CODEX) declares additives non-toxic, but they have been associated with changes to the microbiota changes and thinning of the mucus layer of the gut. Their widespread use has occurred in parallel with increased inflammatory bowel disease (IBD) incidence. This paper reports on the development and validation of surveys to estimate additive intake. (2) Methods: Dietitians created a food-additive database, with a focus on additives that have been associated with IBD. For each additive, information on the CODEX food-category they are permitted in and the associated maximum permissible levels (mg/kg) was recorded. Based on the database, questions to assess early life (part 1) and recent (part 2) additive intake were written. Forward-backward translation from English to Chinese was undertaken. Thirty-one individuals were evaluated to assess understandability. A further fifty-seven individuals completed the tool on two occasions, a fortnight apart; agreement was assessed using Cohen's kappa coefficient or the intra-class correlation coefficient (ICC). (3) Results: The participants reported that it was difficult to remember food intake and estimate portion sizes. The participants also noted confusion around the term 'home-grown'. Instructions and definitions were added; after this, respondents judged the questionnaires as clear. The average kappa coefficient for part 1 and part 2 questions were 0.61 and 0.67, respectively. The average ICC ranged from 0.30 to 0.94; three food lists were removed due to low reliability. (4) Conclusions: Two tools have been created and validated, in two languages, that reliably assess remote and recent food additive intake.

17.
Am J Gastroenterol ; 115(2): 190-201, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31913194

RESUMO

INTRODUCTION: We conducted a systematic review and meta-analysis to compare the prevalence of small intestinal bacterial overgrowth (SIBO) in patients with irritable bowel syndrome (IBS) and controls. METHODS: Electronic databases were searched up to December 2018 for studies reporting SIBO prevalence in patients with IBS. Prevalence rates, odds ratios (ORs), and 95% confidence intervals (CIs) of SIBO in patients with IBS and controls were calculated. RESULTS: We included 25 studies with 3,192 patients with IBS and 3,320 controls. SIBO prevalence in patients with IBS was significantly increased compared with controls (OR = 3.7, 95% CI 2.3-6.0). In studies using only healthy controls, the OR for SIBO in patients with IBS was 4.9 (95% CI 2.8-8.6). With breath testing, SIBO prevalence in patients with IBS was 35.5% (95% CI 33.6-37.4) vs 29.7% (95% CI 27.6-31.8) in controls. Culture-based studies yielded a SIBO prevalence of 13.9% (95% CI 11.5-16.4) in patients with IBS and 5.0% (95% CI 3.9-6.2) in controls with a cutoff value of 10 colony-forming units per milliliter vs 33.5% (95% CI 30.1-36.9) in patients with IBS and 8.2% (95% CI 6.8-9.6) in controls with a cutoff value of 10 colony-forming unit per milliliter, respectively. SIBO prevalence diagnosed by lactulose breath test is much greater in both patients with IBS (3.6-fold) and controls (7.6-fold) compared with glucose breath test. Similar difference is seen when lactulose breath test is compared with culture methods. OR for SIBO in patients with IBS-diarrhea compared with IBS-constipation was 1.86 (95% CI 1.83-2.8). Methane-positive breath tests were significantly more prevalent in IBS-constipation compared with IBS-diarrhea (OR = 2.3, 95% CI 1.2-4.2). In patients with IBS, proton pump inhibitor was not associated with SIBO (OR = 0.8, 95% CI 0.5-1.5, P = 0.55). DISCUSSION: This systematic review and meta-analysis suggests a link between IBS and SIBO. However, the overall quality of the evidence is low. This is mainly due to substantial "clinical heterogeneity" due to lack of uniform selection criteria for cases and controls and limited sensitivity and specificity of the available diagnostic tests.


Assuntos
Síndrome da Alça Cega/epidemiologia , Intestino Delgado , Síndrome do Intestino Irritável/epidemiologia , Antibacterianos/uso terapêutico , Síndrome da Alça Cega/diagnóstico , Síndrome da Alça Cega/tratamento farmacológico , Testes Respiratórios , Estudos de Casos e Controles , Humanos , Prevalência
18.
Nephrology (Carlton) ; 25(1): 5-13, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31587409

RESUMO

Infectious complications are common following kidney transplantation and rank in the top five causes of death in patients with allograft function. Over the last 5 years, there has been emerging evidence that changes in the gastrointestinal microbiota following kidney transplantation may play a key role in the pathogenesis of transplant-associated infections. Different factors have emerged which may disrupt the interaction between the gastrointestinal microbiota and the immune system, which may lead to infective complications in kidney transplant recipients. Over the last 5 years, there has been emerging evidence that changes in the gastrointestinal microbiota following kidney transplantation may play a key role in the pathogenesis of transplant-associated infections. This review will discuss the structure and function of the gastrointestinal microbiota, the changes that occur in the gastrointestinal microbiota following kidney transplantation and the factors underpinning these changes, how these changes may lead to transplant-associated infectious complications and potential treatments which may be instituted to mitigate this risk.


Assuntos
Infecções Bacterianas/microbiologia , Microbioma Gastrointestinal , Trato Gastrointestinal/microbiologia , Transplante de Rim/efeitos adversos , Infecções Oportunistas/microbiologia , Animais , Infecções Bacterianas/imunologia , Infecções Bacterianas/prevenção & controle , Disbiose , Interações Hospedeiro-Patógeno , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/efeitos adversos , Infecções Oportunistas/imunologia , Infecções Oportunistas/prevenção & controle , Prebióticos/administração & dosagem , Probióticos/administração & dosagem , Fatores de Risco , Simbióticos/administração & dosagem , Resultado do Tratamento
19.
Ann Rheum Dis ; 79(1): 132-140, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31662318

RESUMO

OBJECTIVES: Diverse evidence including clinical, genetic and microbiome studies support a major role of the gut microbiome in the common immune-mediated arthropathy, ankylosing spondylitis (AS). We set out to (1) further define the key microbial characteristics driving disease, and (2) examine the effects of tumour necrosis factor-inhibitor (TNFi) therapy upon the microbiome. METHODS: The stools from a case-control cohort of 250 Han-Chinese subjects underwent shotgun metagenomic sequencing. All subjects were genotyped using the Illumina CoreExome SNP microarray. RESULTS: Previous reports of gut dysbiosis in AS were reconfirmed and several notable bacterial species and functional categories were differentially abundant. TNFi therapy was correlated with a restoration the perturbed microbiome observed in untreated AS cases to that of healthy controls, including several important bacterial species that have been previously associated with AS and other related diseases. Enrichment of bacterial peptides homologous to HLA-B27-presented epitopes was observed in the stools of patients with AS, suggesting that either HLA-B27 fails to clear these or that they are involved in driving HLA-B27-associated immune reactions. TNFi therapy largely restored the perturbed microbiome observed in untreated AS cases to that of healthy controls, including several important bacterial species that have been previously associated with AS and other related diseases. TNFi therapy of patients with AS was also associated with a reduction of potentially arthritogenic bacterial peptides, relative to untreated patients. CONCLUSION: These findings emphasise the key role that the gut microbiome plays in driving the pathogenesis of AS and highlight potential therapeutic and/or preventative targets.


Assuntos
Disbiose/microbiologia , Microbioma Gastrointestinal/genética , Metagenoma , Espondilite Anquilosante/microbiologia , Adulto , Grupo com Ancestrais do Continente Asiático , Estudos de Casos e Controles , China , Reações Cruzadas , Disbiose/imunologia , Epitopos/imunologia , Feminino , Microbioma Gastrointestinal/imunologia , Antígeno HLA-B27/imunologia , Humanos , Masculino , Metagenômica , Pessoa de Meia-Idade , Peptídeos/imunologia , Espondilite Anquilosante/tratamento farmacológico , Espondilite Anquilosante/imunologia , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Adulto Jovem
20.
Medicina (Kaunas) ; 55(10)2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31590269

RESUMO

The incidence of infectious complications, compared with the general population and the pre-transplant status of the recipient, increases substantially following kidney transplantation, causing significant morbidity and mortality. The potent immunosuppressive therapy given to prevent graft rejection in kidney transplant recipients results in an increased susceptibility to a wide range of opportunistic infections including bacterial, viral and fungal infections. Over the last five years, several advances have occurred that may have changed the burden of infectious complications in kidney transplant recipients. Due to the availability of direct-acting antivirals to manage donor-derived hepatitis C infection, this has opened the way for donors with hepatitis C infection to be considered in the donation process. In addition, there have been the development of medications targeting the growing burden of resistant cytomegalovirus, as well as the discovery of the potentially important role of the gastrointestinal microbiota in the pathogenesis of post-transplant infection. In this narrative review, we will discuss these three advances and their potential implications for clinical practice.


Assuntos
Infecções por Citomegalovirus/classificação , Hepatite C/complicações , Transplante de Rim/efeitos adversos , Adulto , Citomegalovirus/patogenicidade , Infecções por Citomegalovirus/fisiopatologia , Feminino , Microbioma Gastrointestinal , Hepacivirus/patogenicidade , Hepatite C/fisiopatologia , Humanos , Incidência , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia
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