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Intestinal Bacteria (intestinal + bacteria)
Selected AbstractsIncreased exposure to bacterial antigen RpL7/L12 in early stage colorectal cancer patientsCANCER, Issue 17 2010Annemarie Boleij MSc Abstract BACKGROUND: Intestinal bacteria have long been implicated in colorectal cancer pathology, and many reports point to a close linkage between Streptococcus bovis biotype I (recently renamed Streptococcus gallolyticus) infections and tumors of the human colon. This work aims to investigate the humoral immune response to this bacterium during different stages of colorectal cancer. METHODS: The presence of serum antibodies against S. bovis antigen RpL7/L12, previously assigned as a potential diagnostic antigen, was evaluated in Dutch (n = 209) and American (n = 112) populations using a newly developed enzyme-linked immunosorbent assay. RESULTS: The analyses consistently showed that an immune response against this bacterial antigen was increased in polyp patients and stage I/II colorectal cancer patients as compared with asymptomatic individuals. This was not paralleled by increased antibody production to endotoxin, an intrinsic cell wall component of the majority of intestinal bacteria, which implies that the humoral immune response against RpL7/L12 is not a general phenomenon induced by the loss of colonic barrier function. Notably, increased anti-RpL7/L12 levels were not or were only mildly detected in late stage colorectal cancer patients having lymph node or distant metastasis. CONCLUSIONS: These findings are indicative of an increased exposure to antigen RpL7/L12 during early stages of colon carcinogenesis and suggest that intestinal bacteria such as S. bovis constitute a risk factor for the progression of premalignant lesions into early stage carcinomas. Clearly, the current findings emphasize the necessity for further studies on the possible etiologic relationship between intestinal bacteria and human colorectal cancer. Cancer 2010. © 2010 American Cancer Society. [source] The amount of secreted IgA may not determine the secretory IgA coating ratio of gastrointestinal bacteriaFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 2 2009Takeshi Tsuruta Abstract It is reported that some, but not all, bacteria in human faeces are coated with secretory immunoglobulin A (S-IgA). We evaluated the proportion of S-IgA-coated bacteria to total intestinal bacteria (S-IgA coating ratio) in the gastrointestinal tract of two different strains of mice supplied by two different suppliers. The S-IgA coating ratio was significantly different in each gastrointestinal segment and between mouse suppliers. The amount of non-bacteria-bound IgA (free IgA) in each gastrointestinal segment indicated that this difference in the S-IgA coating ratio might not be due to the amount of secreted IgA. Furthermore, immunoblotting analysis revealed that only a small amount of IgA (<5% to free-IgA) was used for the coating. This indicates that, although sufficient S-IgA was secreted to coat the entire intestinal population of bacteria, only some part of the bacteria were coated with S-IgA. This study suggests that the amount of luminal S-IgA may not determine the S-IgA coating ratio, and that the amount of IgA coating intestinal commensal bacteria is very small. [source] Prebiotics in chronic intestinal inflammationINFLAMMATORY BOWEL DISEASES, Issue 3 2009Mirjam A.C. Looijer, Van Langen MD Abstract Prebiotics are nondigestible fermentable fibers that are reported to have health benefits for the host. Older as well as more recent studies show beneficial effects in experimental colitis and lately also in human inflammatory bowel diseases (IBD), such as Crohn's disease, ulcerative colitis, and chronic pouchitis. In this review we give an overview of the benefits of prebiotics in rodent IBD models and in IBD patients and discuss their possible protective mechanisms. Commensal intestinal bacteria induce and perpetuate chronic intestinal inflammation, whereas others are protective. However, most of the current medications are directed against the exaggerated proinflammatory immune response of the host, some of them toxic and costly. Feeding prebiotics changes the composition of the intestinal microflora toward more protective intestinal bacteria and alters systemic and mucosal immune responses of the host. Therapy for IBD targeting intestinal bacteria and their function is just emerging. Prebiotics have the promise to be relatively safe, inexpensive, and easy to administer. Unraveling their protective mechanisms will help to develop rational applications of prebiotics. However, the initial promising results with dietary prebiotics in preclinical trials as well as small studies in human IBD will need to be confirmed in large randomized controlled clinical trials. (Inflamm Bowel Dis 2008) [source] Seasonal variation of enteric infections and inflammatory bowel diseaseINFLAMMATORY BOWEL DISEASES, Issue 7 2008Amnon Sonnenberg MD Abstract Background: The time trends of inflammatory bowel disease are characterized by short-term variations that affect Crohn's disease and ulcerative colitis alike. The aim of the present study was to test whether these variations might be related to exacerbations of inflammatory bowel disease secondary to superimposed gastrointestinal infection. Methods: The Hospital Episode Statistics (HES) comprises a data set of all patients admitted to hospitals throughout England, which includes inpatients and day cases. This data set was used to analyze the monthly variations in all hospital admissions for Crohn's disease (ICD10 code K50), ulcerative colitis (K51), bacterial intestinal infections (A04), viral intestinal infections (A08), diarrhea and infectious gastroenteritis (A09), upper respiratory infections (J06), pneumonia secondary to unspecified organism (J18), and unspecified acute lower respiratory infection (J22). Results: The temporal analysis revealed similar monthly fluctuations of hospital admissions for Crohn's disease, ulcerative colitis, and bacterial intestinal infections. Viral intestinal infections and infectious gastroenteritis were characterized by different seasonal variations that showed no relationship with any of the fluctuations of inflammatory bowel disease or bacterial intestinal infections. Similarly, respiratory infections resulted in marked cyclical variations in hospital admissions unrelated to any changes in inflammatory bowel disease or enteric infections. Conclusions: The similarity in the time trends of Crohn's disease, ulcerative colitis, and bacterial intestinal infections suggests that superinfection by intestinal bacteria are responsible for the fluctuations in hospital admissions for inflammatory bowel disease. (Inflamm Bowel Dis 2008) [source] CD4+ T lymphocytes mediate colitis in HLA-B27 transgenic rats monoassociated with nonpathogenic Bacteroides vulgatusINFLAMMATORY BOWEL DISEASES, Issue 3 2007Frank Hoentjen MD Abstract Background: HLA-B27/,2 microglobulin transgenic (TG) rats develop spontaneous colitis when raised under specific pathogen-free (SPF) conditions or after monoassociation with Bacteroides vulgatus (B. vulgatus), whereas germ-free TG rats fail to develop intestinal inflammation. SPF HLA-B27 TG rnu/rnu rats, which are congenitally athymic, remain disease free. These results indicate that commensal intestinal bacteria and T cells are both pivotal for the development of colitis in TG rats. However, it is not known if T cells are also required in the induction of colitis by a single bacterial strain. The aim of this study was therefore to investigate the role of T cells in the development of colitis in B. vulgatus,monoassociated HLA-B27 TG rats. Methods: HLA-B27 TG rnu/rnu and rnu/+ rats were monoassociated with B. vulgatus for 8,12 weeks. CD4+ T cells from mesenteric lymph nodes (MLNs) of B. vulgatus,monoassociated rnu/+ TG donor rats were transferred into B. vulgatus,monoassociated rnu/rnu TG recipients. Results:B. vulgatus,monoassociated rnu/+ rats showed higher histologic inflammatory scores and elevated colonic interferon-, mRNA, cecal myeloperoxidase, and cecal IL-1, levels compared to those in rnu/rnu TG rats that did not contain T cells. After transfer of CD4+ cells from colitic B. vulgatus,monoassociated rnu/+ TG donor rats, B. vulgatus,monoassociated rnu/rnu TG recipients developed colitis that was accompanied by B. vulgatus- induced IFN-, production by MLN cells in vitro and inflammatory parameters similar to rnu/+ TG rats. Conclusions: These results implicate CD4+ T cells in the development of colitis in HLA-B27 TG rats monoassociated with the nonpathogenic bacterial strain B. vulgatus. (Inflamm Bowel Dis 2007) [source] Preliminary study of ciprofloxacin in active Crohn's diseaseINFLAMMATORY BOWEL DISEASES, Issue 1 2002Dr. George L. Arnold Abstract Based on limited reports of the successful use of antibiotics in the treatment of Crohn's disease (CD) and on the possibility that intestinal bacteria may be one of the etiologic factors playing a role in the pathogenesis of this condition, we undertook a study to evaluate the use of a broad-spectrum antibiotic in CD. Our team studied the efficacy of adding the antibiotic ciprofloxacin to the treatment of moderately active, but resistant cases of CD. Forty-seven adults with moderately active CD were randomly assigned treatment with ciprofloxacin 500 mg twice daily versus placebo twice daily for 6 months. The primary endpoint was the change in scores on the Crohn's Disease Activity Index (CDAI) from baseline to month 6. Although 47 patients were randomized, at 1 month of follow-up 28 patients received ciprofloxacin and 19 received placebo. The mean entry CDAI scores were not significantly different: 187 for the ciprofloxacin group versus 230 for the placebo group (p = 0.638). Mean CDAI scores at the completion of study were 112 for the ciprofloxacin group (n = 25) and 205 for the placebo group (n = 12), (p < 0.001). Disease remission is defined as a decrease in the CDAI score to less than 150 points. Our preliminary study suggests that ciprofloxacin may be an effective agent when added to the treatment of moderately active, resistant CD. [source] Probiotics and inflammatory bowel disease: Is there a scientific rationale?INFLAMMATORY BOWEL DISEASES, Issue 2 2000Dr. Fergus Shanahan Abstract Most conventional forms of drug therapy suppress or modify the host immunoinflammatory response and neglect the other contributor to disease pathogenesis,the environmental microflora. Probiotics are live microbial food ingredients that alter the enteric microflora and have a beneficial effect on health. The rationale for using probiotics in IBD is mainly based on evidence from human studies and experimental animal models implicating intestinal bacteria in the pathogenesis of these disorders. The relationship between bacteria and intestinal inflammation is complex and does not appear to reflect a simple cause and effect. Similarly, the field of probiotics is complex and in need of rigorous research. Until the indigenous flora are better characterized and mechanisms of probiotic action defined, the promise of probiotics in IBD is unlikely to be fulfilled. Because of strain-specific variability and clinical and therapeutic heterogeneity within Crohn's disease and ulcerative colitis, it cannot be assumed that a given probiotic is equally suitable for all individuals. Although preliminary results of probiotic therapy in animal models and humans with ulcerative colitis and pouchitis have been encouraging, their efficacy in treatment or maintenance of remission of Crohn's disease remains to be clarified. However, the circumstantial evidence for some form of biotherapeutic modification of the enteric flora in Crohn's disease seems compelling. In the future, probiotics may offer a simple adjunct to conventional therapy with the emphasis on diet shifting from one of nutritional replenishment alone to a more functional role. [source] Bacteria,diet interactions affect longevity in the medfly ,Ceratitis capitataJOURNAL OF APPLIED ENTOMOLOGY, Issue 9-10 2008M. Ben-Yosef Abstract Mediterranean fruit flies (Ceratitis capitata Wiedemann, Dipt.: Tephritidae) harbour a diverse community of bacteria in their digestive system. This microbiota may have important functions impacting on the fly's fitness. Recently, we described the effect of eliminating intestinal bacteria on the reproductive success of C. capitata males and females. Here, we expand the view on the nature of fly,bacteria interactions by examining the effect of bacteria on male and female longevity. Antibiotics were used to suppress the gut bacterial community and mortality rates were compared between antibiotic-treated and non-treated flies when either nutritionally stressed (maintained on sugar) or provided with a full diet. These tests revealed that eliminating the gut bacterial population prolonged longevity, but only when flies were nutritionally stressed, indicating that the effect of bacteria on lifespan was diet dependent. Considering these results in light of other known effects of bacteria on fitness components of the fly demonstrates a cost-benefit relationship between C. capitata and its gut microbiota. [source] Phylogenetic analysis of intestinal bacteria in the Chinese mitten crab (Eriocheir sinensis)JOURNAL OF APPLIED MICROBIOLOGY, Issue 3 2007K. Li Abstract Aims:, To identify the dominant intestinal bacteria in the Chinese mitten crab, and to investigate the differences in the intestinal bacteria between pond-raised and wild crabs. Methods and Results:, The diversity of intestinal bacteria in the Chinese mitten crabs was investigated by denaturing gradient gel electrophoresis (DGGE) fingerprinting, 16S rRNA gene clone library analysis and real-time quantitative PCR. The principal component analysis of DGGE profiles indicated that substantial intersubject variations existed in intestinal bacteria in pond-raised crab. The sequencing of 16S rRNA genes revealed that 90,95% of the phylotypes in the clone libraries were affiliated with Proteobacteria and Bacteroidetes. Some genera were identified as unique in wild crabs and in pond-raised crabs, whereas Bacteroidetes was found to be common in all sampled crab groups. Real-time quantitative PCR indicated that the abundance of Bacteroides and the total bacterial load were approximately four-to-10 times higher in pond-raised crabs than in wild crabs. A significant portion of the phylotypes shared low similarity with previously sequenced organisms, indicating that the bacteria in the gut of Chinese mitten crabs are yet to be described. Conclusions:, The intestinal bacteria of pond-raised crabs showed higher intersubject variation, total diversity and abundance than that observed in wild crabs. The high proportion of the clones of Proteobacteria and Bacteroidetes in the clone library is an indication that these bacteria may be the dominant population in the gut of the Chinese mitten crab. Significance and Impact of the Study:, This study demonstrated obvious differences in the intestinal bacterial composition of pond-raised crabs and wild crabs. This knowledge will increase our understanding of the effects of aquaculture operations on bacterial community composition in the crab gut and provide necessary data for the development of probiotic products for crab cultivation. [source] Growth-inhibiting effects of seco-tanapartholides identified in Artemisia princeps var. orientalis whole plant on human intestinal bacteriaJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2003S.-H. Cho Abstract Aims: The present work aimed at isolating antibacterial constituents from the whole plant of Artemisia princeps var. orientalis active towards nine human intestinal bacteria. Methods and Results: The growth-inhibiting activities of materials derived from the Artemisia whole plant towards test bacteria were examined using an impregnated paper disc method. The biologically active constituents of the Artemisia whole plant were characterized as the sesquiterpene lactones seco-tanapartholides A and B by spectroscopic analysis. In a test using 1 mg per disc, seco-tanapartholides A and B produced a clear inhibitory effect against Clostridium perfringens, Bacteroides fragilis and Staphylococcus aureus. These compounds did not affect the growth of test lactic acid-producing bacteria (Bifidobacterium adolescentis, Bif. breve, Lactobacillus acidophilus and Lact. casei) and Escherichia coli, whereas weak growth inhibition towards Bif. bifidum was observed. At 0·5 mg per disc, seco-tanapartholides A and B exhibited moderate growth inhibition towards Cl. perfringens but weak growth inhibition towards Bact. fragilis and Staph. aureus. Conclusions: Inhibitory action of seco-tanapartholides A and B towards specific bacteria without any adverse effects on lactic acid-producing bacteria may be an indication of at least one of the pharmacological actions of A. princeps var. orientalis whole plant. Significance and Impact of the Study: These naturally occurring Artemisia whole plant-derived materials could be useful as a new preventive agent against various diseases caused by harmful intestinal bacteria such as clostridia. [source] Repetitive administration of Shaoyao-Gancao-tang to rats restores the bioavailability of glycyrrhizin reduced by antibiotic treatmentJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 11 2003Ju-Xiu He ABSTRACT Shaoyao-Gancao-tang (SGT), a traditional Chinese formulation, is often used together with antibiotics such as amoxicillin and metronidazole (AMPC-MET) for the treatment of peptic ulcers in Japan. However, the bioavailability of glycyrrhizin (GL) in SGT is severely reduced by a single administration of AMPC-MET, and the reducing effect continues for 12 days. GL is one of the major pharmacologically important glycosides in SGT and is transformed into the active metabolite 18,-glycyrrhetic acid (GA) by intestinal bacteria in the gut, followed by absorption of the latter into the blood. In order to reduce the negative effect of AMPC-MET on the bioavailability of GL, the optimum scheduling of the medications was examined. We found that the reduction in the plasma GA concentration and the GL-metabolizing activity in faeces caused by a single dose of AMPC-MET could be sharply attenuated by the repetitive administration of SGT for 4 days. The GA concentration and the GL-metabolizing activity were strongly enhanced by further continuous administration of SGT. These findings suggest that repetitive administration of SGT starting 1 or 2 days after the administration of AMPC-MET speeds the recovery of the bioavailability of GL in SGT. Similar strategies for administering medications may also be useful for combination therapy of antibiotics with other traditional Chinese formulations containing bioactive glycosides. [source] Metronidazole Increases Intracolonic but Not Peripheral Blood Acetaldehyde in Chronic Ethanol-Treated RatsALCOHOLISM, Issue 4 2000Jyrki Tillonen Background: Metronidazole leads to the overgrowth of aerobic flora in the large intestine by reducing the number of anaerobes. According to our previous studies, this shift may increase intracolonic bacterial acetaldehyde formation if ethanol is present. Metronidazole is also reported to cause disulfiram-like effects after alcohol intake, although the mechanism behind this is obscure. Therefore, the aim was to study the effect of long-term metronidazole and alcohol treatment on intracolonic acetaldehyde levels and to explore the possible role of intestinal bacteria in the metronidazole related disulfiram-like reaction. Methods: A total of 32 rats were divided into four groups: controls (n= 6), controls receiving metronidazole (n= 6), ethanol group (n= 10), and ethanol and metronidazole group (n= 10). All rats were pair-fed with the liquid diet for 6-weeks, whereafter blood and intracolonic acetaldehyde levels and liver and colonic mucosal alcohol (ADH) and aldehyde dehydrogenase (ALDH) activities were analyzed. Results: The rats receiving ethanol and metronidazole had five times higher intracolonic acetaldehyde levels than the rats receiving only ethanol (431.4 ± 163.5 ,M vs. 84.7 ± 14.4 ,M, p= 0.0035). In contrast, blood acetaldehyde levels were equal. Cecal cultures showed the increased growth of Enterobacteriaceae in the metronidazole groups. Metronidazole had no inhibitory effect on hepatic or colonic mucosal ADH and ALDH activities. Conclusions: The increase in intracolonic acetaldehyde after metronidazole treatment is probably due to the replacement of intestinal anaerobes by ADH-containing aerobes. Unlike disulfiram, metronidazole neither inhibits liver ALDH nor increases blood acetaldehyde. Thus, our findings suggested that the mechanism behind metronidazole related disulfiram-like reaction might be located in the gut flora instead of the liver. [source] Food and feed components for gut health-promoting adhesion of E. coli and Salmonella entericaJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 11 2008Petra M Becker Abstract BACKGROUND: A host runs less risk of contracting a gastrointestinal infection when enteropathogenic bacteria adhere to dietary fibers instead of to epithelial cell receptors. The aim of this study was to test the binding capacity of food and feed components for intestinal bacteria from various hosts using a miniaturized in vitro assay. In total, 18 dietary components were tested with four strains of E. coli, seven strains of Salmonella enterica and two strains of Lactobacillus. RESULTS: A comparison of the results obtained for all Salmonella strains tested revealed that konjac gum and sesame seed extract represented the most efficient binding matrices. Similarly, for all E. coli strains tested, sesame seed extract and artichoke performed well as binding matrices. Salmonella isolates from chickens adhered best to sesame seed extract. E. coli K88 and S. enterica sv. Typhimurium isolated from pigs effectively bound to BioMos®, pumpkin, sesame seed extract, and tomato. Sesame seed extract and tomato also had adhesive capacities for E. coli K 99, S. enterica sv. Dublin, and S. enterica sv. Typhimurium from calves. With human isolates, konjac gum showed a high binding potential for S. enterica and E. coli. CONCLUSION: The adhesion screening of different food and feed components resulted in highly discriminating product rankings. Copyright © 2008 Society of Chemical Industry [source] In vitro fermentation of cereal dietary fibre carbohydrates by probiotic and intestinal bacteriaJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 8 2002Ross Crittenden Abstract A range of probiotic and other intestinal bacteria were examined for their ability to ferment the dietary fibre carbohydrates ,-glucan, xylan, xylo-oligosaccharides (XOS) and arabinoxylan. ,-Glucan was fermented by Bacteroides spp and Clostridium beijerinckii but was not fermented by lactobacilli, bifidobacteria, enterococci or Escherichia coli. Unsubstituted xylan was not fermented by any of the probiotic bacteria examined. However, many Bifidobacterium species and Lactobacillus brevis were able to grow to high yields using XOS. XOS were also efficiently fermented by some Bacteroides isolates but not by E coli, enterococci, Clostridium difficile, Clostridium perfringens or by the majority of intestinal Lactobacillus species examined. Bifidobacterium longum strains were able to grow well using arabinoxylan as the sole carbon source. These organisms hydrolysed and fermented the arabinosyl residues from arabinoxylan but did not substantially utilise the xylan backbone of the polysaccharide. Arabinoxylan was not fermented by lactobacilli, enterococci, E coli, C perfringens or C difficile and has potential to be an applicable carbohydrate to complement probiotic Bif longum strains in synbiotic combinations. © 2002 Society of Chemical Industry [source] Clinical trial: randomized study of clarithromycin versus placebo in active Crohn's diseaseALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 12 2008K. LEIPER Summary Background, Crohn's disease is characterized by defective innate immune responses to intestinal bacteria. Clarithromycin is a broad-spectrum antibiotic that has good penetration into macrophages. Aim, To assess the efficacy of clarithromycin in active Crohn's disease. Methods, Patients with Crohn's disease activity index > 200 and serum C-reactive protein , 10 mg/L were randomized to receive clarithromycin 1 g o.d. or placebo for 3 months. Patients taking more than 10 mg/day prednisolone or 3 mg/day budesonide were excluded. Primary outcome was remission (CDAI , 150) or response (fall in CDAI , 70 from pre-treatment level) at 3 months. Results, The trial was stopped after 41 patients had been recruited because of poor overall efficacy. There was no difference in combined remission or response rates at 3 months between clarithromycin: 26% (five of 19) and placebo: 27% (six of 22) (P = 1.00). The mean (s.d.) fall in Crohn's disease activity index was 35 (80) clarithromycin and ,2 (114) placebo (P = 0.24). However, post hoc analysis showed a significant difference in response/remission determined by Crohn's disease activity index after 1 month: 53% (10 of 19) clarithromycin vs. 14% (three of 22) placebo (P = 0.01). Conclusion, Clarithromycin 1 g for 3 months is ineffective in active Crohn's disease but possible benefit was observed at 1 month, suggesting that an initial effect may be attenuated by subsequent bacterial resistance. [source] Efficacy of Lactobacillus GG in maintaining remission of ulcerative colitisALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 11 2006M. A. ZOCCO Summary Background Aminosalicylates are the mainstay of therapy to prevent relapse of quiescent ulcerative colitis. The rationale for using probiotics is based on the evidence implicating intestinal bacteria in the pathogenesis of this disorder. Aim To evaluate the efficacy of Lactobacillus GG alone or in combination with mesalazine vs. mesalazine as maintenance treatment in ulcerative colitis. Patients and methods 187 ulcerative colitis patients with quiescent disease were randomized to receive Lactobacillus GG 18 × 109 viable bacteria/day (65 patients), mesalazine 2400 mg/day (60 patients) or Lactobacillus GG + mesalazine (62 patients). Disease activity index, endoscopic and histological scores were determined at 0, 6 and 12 months and in case of relapse. The primary end point was to evaluate sustained remission. Results Overall analysis showed no difference in relapse rate at 6 (P = 0.44) and 12 months (P = 0.77) among the three treatment groups. However, the treatment with Lactobacillus GG seems to be more effective than standard treatment with mesalazine in prolonging the relapse-free time (P < 0.05). Conclusions Lactobacillus GG seems to be effective and safe for maintaining remission in patients with ulcerative colitis, and it could represent a good therapeutic option for preventing relapse in this group of patients. [source] Bifidobacterium and Lactobacillus DNA in the human placentaLETTERS IN APPLIED MICROBIOLOGY, Issue 1 2009R. Satokari Abstract Aims:, Bifidobacteria and lactobacilli are part of the human normal intestinal microbiota and may possibly be transferred to the placenta. It was hypothesized that intestinal bacteria or their components are present in the placenta and that the foetus may be exposed to them. We investigated the presence of bifidobacteria and lactobacilli and their DNA in the human placenta. Methods and Results:, We studied 34 human placentae (25 vaginal and nine caesarean deliveries) for the presence Bifidobacterium spp. and Lactobacillus rhamnosus. Cultivation was used for the detection of viable cells and genus and species-specific PCR for the detection of DNA. No bifidobacteria or lactobacilli were found by cultivation. Bifidobacterial DNA was detected in 33 and L. rhamnosus DNA in 31 placenta samples. Conclusions:, DNA from intestinal bacteria was found in most placenta samples. The results suggest that horizontal transfer of bacterial DNA from mother to foetus may occur via placenta. Significance and Impact of the Study:, Bacterial DNA contains unmethylated CpG oligodeoxynucleotide motifs which induce immune effects. Specific CpG motifs activate Toll-like receptor 9 and subsequently trigger Th-1-type immune responses. Although the newborn infant is considered immunologically immature, exposure by bacterial DNA may programme the infant's immune development during foetal life earlier than previously considered. [source] ,-Glucuronidase inhibitor tectorigenin isolated from the flower of Pueraria thunbergiana protects carbon tetrachloride-induced liver injuryLIVER INTERNATIONAL, Issue 4 2003Hae-Woong Lee Abstract Background/Aim: To understand the relationship between the fluctuation in serum ,-glucuronidase and hepatotoxicity, an inhibitor of ,-glucuronidase was isolated from the flowers of Pueraria thunbergiana and its hepatoprotective activity was measured. Method: Tectorigenin was isolated from the flowers of pueria thunbergiana as an inhibitor of ,-glucuronidase, and serum ALT, AST and biological parameters as markers for its hepatoprotective activity were measured on CCl4 -induced liver injury in mice. The relationship between serum ,-glucuronidase and hepatoprotective activities in mice was measured. Results: When tectorigenin at a dose of 100 mg/kg was intraperitoneally administered on CCl4 -induced liver injury in mice, it significantly inhibited the increase of plasma ALT, AST and LDH activities. The inhibitory effect of tectorigenin is much more potent than that of dimethyl diphenyl bicarboxylate (DDB), which has been used as a commercial hepatoprotective agent. When tectoridin transformed to tectorigenin by intestinal bacteria was orally administered to mice, it showed hepatoprotective activity. However, when tectoridin was intraperitoneally administrated to mice, it did not exhibit hepatoprotective activity. Moreover, orally administered tectoridin not only inhibited ,-glucuronidase but also increased GSH content and GST activity on CCl4 -induced hepatotoxicity of mice. Conclusion: We insist that an inhibitor of ,-glucuronidase tectorigenin may be hepatoprotective and tectoridin should be a prodrug transformed to tectorigenin. [source] Isolation and identification of metabolites from dihydromyricetinMAGNETIC RESONANCE IN CHEMISTRY, Issue 11 2007Yansong Zhang Abstract Dihydromyricetin (DHM) is the major bioactive constituent of Rattan Tea, which is the tender stems and leaves of Ampelopsis grossendentata. Seven metabolites (2,8) of DHM (1) were obtained by the chromatographic method. The metabolites 2,5 were obtained from the urine of rats administered orally with DHM; and metabolites 6,8 were detected in the fecal specimens of rats, which were also produced by human intestinal bacteria (HIB) in vitro, and were separated from the cultured media of HIB containing DHM. Their structures were elucidated as 5,7,3,,5,-tetrahydroxyflavanonol (2); 5,7,3,,5,-tetrahydroxy-4,-methoxyflavanonol (3); 5,7,4,,5,-tetrahydroxy-3,-methoxyflavanonol (4); and dihydromyricetin- O -5-,- D -glucuronide (5); (2R,3S)-5,7,3,,4,,5,-pentahydroxyflavanonol (6); 3,4,5,7,3,,4,,5,-hepthydroxyflavan (7) and 5,7,3,,4,,5,-pentahydroxyflavanone (8) on the basis of UV, NMR and LC-MS/MS data. These seven metabolites were formed through familiar metabolic reactions. Dihydromyricetin- O -5-,- D -glucuronide (5) is a new compound. The 13C-NMR data of (2) and (4) are reported for the first time. Copyright © 2007 John Wiley & Sons, Ltd. [source] Metabolism of Maillard reaction products by the human gut microbiota , implications for healthMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 9 2006Kieran M. Tuohy Abstract The human colonic microbiota imparts metabolic versatility on the colon, interacts at many levels in healthy intestinal and systemic metabolism, and plays protective roles in chronic disease and acute infection. Colonic bacterial metabolism is largely dependant on dietary residues from the upper gut. Carbohydrates, resistant to digestion, drive colonic bacterial fermentation and the resulting end products are considered beneficial. Many colonic species ferment proteins but the end products are not always beneficial and include toxic compounds, such as amines and phenols. Most components of a typical Western diet are heat processed. The Maillard reaction, involving food protein and sugar, is a complex network of reactions occurring during thermal processing. The resultant modified protein resists digestion in the small intestine but is available for colonic bacterial fermentation. Little is known about the fate of the modified protein but some Maillard reaction products (MRP) are biologically active by, e. g. altering bacterial population levels within the colon or, upon absorption, interacting with human disease mechanisms by induction of inflammatory responses. This review presents current understanding of the interactions between MRP and intestinal bacteria. Recent scientific advances offering the possibility of elucidating the consequences of microbe-MRP interactions within the gut are discussed. [source] Enteric bacteria may play a role in mammalian arsenic metabolismAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 6 2001Koichi Kuroda Abstract The cecal content of rats administered dimethylarsinic acid for 6 months via drinking water was cultured in GAM medium with 10,mg l,1 of dimethylarsinic acid. Arsenic compounds in the culture were analyzed by ion chromatography with inductively coupled plasma mass spectrometry (IC,ICP-MS). Dimethylarsinic acid was metabolized. Two bacterial Escherichia coli strains, A3-4 and A3-6, were isolated from the culture. These strains metabolized dimethylarsinic acid and yielded two unidentified arsenic compounds, M-2 and M-3. A3-6 methylated dimethylarsinic acid to trimethylarsine oxide. Both strains metabolized trimethylarsine oxide and yielded an unidentified arsenic compound, M-1. These unknown arsenic compounds were the same compounds as detected in the urine and the feces of rats administered dimethylarsinic acid. The strains reduced arsenate to arsenite efficiently. Cysteine was required for metabolism of dimethylarsinic acid by these bacteria, but glutathione was not required. These results strongly suggested that the intestinal bacteria have a different arsenic metabolism from that in mammals and that they may play a possible role in mammalian arsenic metabolism. Copyright © 2001 John Wiley & Sons, Ltd. [source] Assessing the use of a dietary probiotic/prebiotic as an enhancer of spinefoot rabbitfish Siganus rivulatus survival and growthAQUACULTURE NUTRITION, Issue 6 2007A.Y. EL-DAKAR Abstract The use of prebiotics and probiotics as feed supplements that improve efficiency of intestinal bacteria is becoming de rigueur in animal husbandry in many regions worldwide. We tested the effects of a commercial probiotic (Biogen®) containing allicin, high unit hydrolytic enzyme, Bacillus subtilis spores and ginseng extracts on survival, growth, carcass composition and feed cost/benefit in rabbitfish Siganus rivulatus. Fifteen net cages (100 × 100 × 40 cm; L × W × H) were stocked with 10 juvenile rabbitfish (10.3 g per fish) each and placed in a large rectangular tank and offered feed at 4% body weight daily. Cages were offered one of five isonitrogenous and isocaloric diets containing 0, 1, 2, 3 and 4 g kg,1 probiotic at three replicates per treatment for 98 days. Fish in all cages were weighed at 2-week intervals and feed regimen was adjusted accordingly. Rabbitfish offered the control diet exhibited lower growth and feed utilization than all experimental treatments. There was no effect of probiotic inclusion level on survival but growth was better at all inclusion levels than in the control. No significant differences (P > 0.05) in growth were observed among fish groups fed various levels of the probiotic. Carcass composition was not affected by dietary probiotic inclusion. Ultimately, when all variables are considered, Biogen® inclusion to diets appears to reduce feed cost per unit growth of rabbitfish. [source] Lactic acid bacteria vs. pathogens in the gastrointestinal tract of fish: a reviewAQUACULTURE RESEARCH, Issue 4 2010Einar Ringų Abstract Intensive fish production worldwide has increased the risk of infectious diseases. However, before any infection can be established, pathogens must penetrate the primary barrier. In fish, the three major routes of infection are the skin, gills and gastrointestinal (GI) tract. The GI tract is essentially a muscular tube lined by a mucous membrane of columnar epithelial cells that exhibit a regional variation in structure and function. In the last two decades, our understanding of the endocytosis and translocation of bacteria across this mucosa, and the sorts of cell damage caused by pathogenic bacteria, has increased. Electron microscopy has made a valuable contribution to this knowledge. In the fish-farming industry, severe economic losses are caused by furunculosis (agent, Aeromonas salmonicida spp. salmonicida) and vibriosis [agent, Vibrio (Listonella) anguillarum]. This article provides an overview of the GI tract of fish from an electron microscopical perspective focusing on cellular damage (specific attack on tight junctions and desmosomes) caused by pathogenic bacteria, and interactions between the ,good' intestinal bacteria [e.g. lactic acid bacteria (LAB)] and pathogens. Using different in vitro methods, several studies have demonstrated that co-incubation of Atlantic salmon (Salmo salar L.) foregut (proximal intestine) with LAB and pathogens can have beneficial effects, the cell damage caused by the pathogens being prevented, to some extent, by the LAB. However, there is uncertainty over whether or not similar effects are observed in other species such as Atlantic cod (Gadus morhua L.). When discussing cellular damage in the GI tract of fish caused by pathogenic bacteria, several important questions arise including: (1) Do different pathogenic bacteria use different mechanisms to infect the gut? (2) Does the gradual development of the GI tract from larva to adult affect infection? (3) Are there different infection patterns between different fish species? The present article addresses these and other questions. [source] Novel physiological function of fructooligosaccharidesBIOFACTORS, Issue 1-4 2004Takahisa Tokunaga Abstract Two key properties of short chain fructooligosaccharides (sc-FOS) which lead to physiological functions are indigestibility in the small intestine and fermentability in the colon. Sc-FOS is converted into short chain fatty acids (SCFAs) by intestinal bacteria in the colon and absorbed. Through the metabolic pathway, sc-FOS improves gastrointestinal (GI) condition such as relief from constipation, formation of preferable intestinal microflora and intestinal immunomodulation those are known as prebiotics' function. Besides improvement of GI condition, dietary sc-FOS influences on calcium and magnesium absorption in the colon. A major mineral absorption site is the small intestine, but the colon also works as a Ca and Mg absorption site with an aid of SCFAs made from sc-FOS. Furthermore dietary sc-FOS influences on bioavailability of soy-isoflavones. Plasma and urinal concentration of Genistein and Daidzein, aglycones of Daidzin and Genistin, are higher in the rat fed with sc-FOS than the control rat. An additive effect of dietary isoflavone and sc-FOS was observed on the bone mineral density in OVX mice and moreover sc-FOS increased ceacal ,-glycosidase activity and equol production. These results suggest that FOS increase the bioavailability of isoflavones. [source] Increased exposure to bacterial antigen RpL7/L12 in early stage colorectal cancer patientsCANCER, Issue 17 2010Annemarie Boleij MSc Abstract BACKGROUND: Intestinal bacteria have long been implicated in colorectal cancer pathology, and many reports point to a close linkage between Streptococcus bovis biotype I (recently renamed Streptococcus gallolyticus) infections and tumors of the human colon. This work aims to investigate the humoral immune response to this bacterium during different stages of colorectal cancer. METHODS: The presence of serum antibodies against S. bovis antigen RpL7/L12, previously assigned as a potential diagnostic antigen, was evaluated in Dutch (n = 209) and American (n = 112) populations using a newly developed enzyme-linked immunosorbent assay. RESULTS: The analyses consistently showed that an immune response against this bacterial antigen was increased in polyp patients and stage I/II colorectal cancer patients as compared with asymptomatic individuals. This was not paralleled by increased antibody production to endotoxin, an intrinsic cell wall component of the majority of intestinal bacteria, which implies that the humoral immune response against RpL7/L12 is not a general phenomenon induced by the loss of colonic barrier function. Notably, increased anti-RpL7/L12 levels were not or were only mildly detected in late stage colorectal cancer patients having lymph node or distant metastasis. CONCLUSIONS: These findings are indicative of an increased exposure to antigen RpL7/L12 during early stages of colon carcinogenesis and suggest that intestinal bacteria such as S. bovis constitute a risk factor for the progression of premalignant lesions into early stage carcinomas. Clearly, the current findings emphasize the necessity for further studies on the possible etiologic relationship between intestinal bacteria and human colorectal cancer. Cancer 2010. © 2010 American Cancer Society. [source] | |||||||||||||||||||