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PubMedDate not supplied

[Bacterial-fungal associations in the intestine under the conditions of colonization by yeast-like fungi of the genus Candida].

The composition of the fecal microflora in somatic patients and patients with enteric infections under the conditions of surpluscolonization by yeast-like fungi of the genus Candida was analyzed. The study revealed that the high level of fungal contamination was linked with decreased colonization resistance of the intestine (deficiency in bifidoflora) and with the presence of opportunistic microorganisms: Staphylococcus aureus, hemolytic and lactose-negative Escherichia coli, as well as nonfermenting Gram negative bacteria. The antilysozyme activity of enterobacteria was found to increase in the course of their joint cultivation with fungi of the genus Candida, that may be regarded as one of the mechanisms of the formation and maintenance of pathobiocenosis.

Bacteria↗
PubMed2001

[Pathogenetic mechanisms of impaired intestinal microflora in patients with destructive pulmonary tuberculosis].

Following 2-3 months of combined chemotherapy, most (97.5%) patients with destructive pulmonary tuberculosis were found to develop pathological changes in the intestinal microflora. Of them 92.3% had bifidobacterium deficiency, which creates conditions for opportunistic microorganisms to colonize the bowel, promoting the development of an inflammatory process in the gastroduodenal area, Bifidobacterium deficiency being a pathogenetic factor and opportunistic microbes acting as an etiological factor of the impaired intestinal microflora. Assessing of dysbiotic impairments makes it possible to specify the mechanisms of development of toxic reactions and inflammatory processes in the digestive tract.

Antitubercular Agents↗
PubMed1994

[Absorption, distribution and excretion of vitamin B12].

In our first communication, the complexity of vitamin B12 digestive transport was considered. This second presentation demonstrates the route of the vitamin in the body. As cobalamin or vitamin B12 has existed for Four Billion Years, they figure without any doubt amongst those molecules which have the most complex structure. The rarity of an architecture organised around a cobalt atom confirms their high level of originality. Their exceptional character is reflected in their cycle such as for mammals and for man where the intervention of binders, such as intrinsic factor, transcobalamin and haptocorrin is necessary for transporting them. As far as cellular metabolism is concerned, it is especially loaded sometimes with folates in the transfer of the methyl group. The Molecules are spiked with hydrophobic sites. Their membrane transfer is facilitated by several types of receptors. The intestinal absorption, which appears to require the presence of two receptors and two transporters, remains for the moment a unique assimilation model. The very probable existence of an enterohepatic cycle as well as a renal reabsorption saves this molecule, itself synthesised by microorganisms only.

Humans↗
PubMedDate not supplied

[Intestinal autoflora of the test subjects in a 6-month biological engineering experiment].

During a 6-month bioengineering experiment the intestinal microflora of four test subjects was examined. Changes in the composition of different groups of intestinal microflora (bifidobacteria, lactic-acid bacteria, sporogenous anaerobes, proteus, etc) were found. In spite of the unstable pattern of the intestinal microflora and its tendency for simplification, the total number of microorganisms in 1 g of feces remained relatively unchanged in all the test subjects.

Biomedical Engineering↗
PubMed2005

The intestinal flora in inflammatory bowel disease: normal or abnormal?

PURPOSE OF REVIEW: The human gut is the natural habitat for a large and dynamic bacterial community. There is a substantial body of evidence implicating the resident flora in the pathogenesis of chronic intestinal inflammation. This review discusses the possible role of a microbial imbalance in the pathophysiology of inflammatory bowel disease. RECENT FINDINGS: Recently developed molecular biologic tools suggest that a sizeable part of the microbial populations of the human gut remains to be defined. Conversely, the relevance of gut bacteria in the host's physiology is well documented. The specialised lymphoid follicles of the gut mucosa are the major sites for induction of effector and regulatory mechanisms of the intestinal immune system, and it is now becoming clear that resident and in-transit microorganisms play an essential role in the homeostasis of local and systemic immunity. An infectious origin of inflammatory bowel disease is not supported by our current knowledge. Several studies, however, have disclosed substantial differences in the intestinal flora between patients with inflammatory bowel disease and healthy subjects, in regard to both composition and mucosal colonisation. Aggressive species are abundant on the inflammatory bowel disease mucosal surface whereas protective genera are underrepresented, but the biologic relevance of these changes needs further investigation. SUMMARY: A balanced microbial environment would likely help in both prevention and control of inflammatory bowel disease. Research is needed to identify microorganisms able to mediate immunoregulation in the gut mucosa.

Bacteria, Aerobic↗
PubMed1985

[Interaction of Yersinia pseudotuberculosis with the epithelium of the small intestine in experimental infection].

Some data showing specific ways of interaction of Yersinia pseudotuberculosis with the epithelium of the small intestinal mucosa have been received for the first time by using light microscopy of semithin sections. Comparative study of the lesion of the epithelium of different parts of rabbit small intestine by oral inoculation with Yersinia tuberculosis has expanded the ideas of the infection entry. It has been established for the first time that the most intensive penetration of the microorganisms into the epithelium of the mucous membrane takes place in the duodenum and jejunum. As the infected contents is evacuated via the intestinal tract, the Yersinia pathogenicity decreases, and in the ileum, the invasion of the microorganisms becomes less pronounced. It has been revealed that in pseudotuberculosis, there takes place a repeated dissemination of the infection in the intestinal tract because of decay of the involved enterocytes, which is of pathogenetic importance for the progress and outcome of the infection.

Animals↗
PubMed2003

Decreased gastric bacterial killing and up-regulation of protective genes in small intestine in gastrin-deficient mouse.

Gastrin regulates gastric acid secretion, believed to be primarily responsible for killing ingested microbes. We examined gastric killing of gavaged E. coli in gastrin-deficient mice, which have decreased gastric acid production. Additionally, the expression of intestinal genes involved in epithelial protection were analyzed: the mucus layer glycoprotein muclin, the polymeric Ig receptor, trefoil factor 3, and small proline-rich protein 2a (sprr2a). Gastric pH was 2.5 pH units greater in gastrin-deficient mice, and E. coli survival was increased greater than 20-fold at 10 min after gavage compared to control. Muclin and sprr2a gene expression were significantly increased (2.0- and 2.6-fold) in the intestine, and antibiotic treatment reversed these effects. In conclusion, reduced gastric acid secretion results in increased survival of ingested microorganisms in gastrin-deficient mice. Bacterial survival is associated with increased expression of muclin and sprr2a in the intestine, indicating that these genes play protective roles in the intestine.

Animals↗
PubMed1987

Oral immunization in adult mice to live and heat-killed Vibrio cholerae.

Effects of systemic and intestinal local immune responses in mice fed ad libitum and forcedly with live or heat-killed Vibrio cholerae on the elimination of vibrios from the intestine were investigated. In mice fed with live vibrios, ad libitum feeding could induce potential delayed-type hypersensitivity and rapid production of vibriocidal antibody in the serum whereas forcedly feeding suppressed the delayed-type hypersensitivity and retarded the antibody production. In contrast, when killed microorganisms were used as antigens, significant delayed-type hypersensitivity and rapid response of vibriocidal antibody were induced in forcedly fed mice although ad libitum feeding suppressed the induction of the delayed-type hypersensitivity and retarded the production of vibriocidal antibody. The elimination of vibrios from the intestine of mice was promoted in both mice groups fed ad libitum and forcedly with live vibrios but not with killed microorganisms. Total IgA in the intestinal contents of mice fed with live vibrios both ad libitum and forcedly were higher than those of mice fed with killed antigens. In addition, when the extracts of intestinal contents were absorbed by live antigens, IgA contents in mice fed with live vibrios were reduced more markedly than those in mice immunized orally by the feeding with killed antigens. These findings suggested that the elimination of vibrios from the organ was closely related to local IgA antibody response to heat-labile substance of live Vibrio cholerae.

Animals↗
PubMedDate not supplied

[A new sorbent for the treatment of intestinal infections].

A new inorganic sorbent is proposed endowed with high adsorption-chemical activity towards microorganisms. Animal studies showed that the preparation "Evirhip" is superior to coal-based sorbents (KAY and CKN) and polymethilsiloxan (PMS) towards pathogenic microorganisms, PMS having relatively higher adhesive activity towards Salmonellas than coal-based sorbents.

Animals↗
PubMed1999

The composition and function of M cell apical membranes: implications for microbial pathogenesis.

M cells, an epithelial cell phenotype that occurs only over organized mucosal lymphoid follicles, deliver samples of foreign material by transepithelial transport from the lumen to organized lymphoid tissues within the mucosa of the small and large intestines. The apical membranes of M cells in the intestine are designed to facilitate adherence and uptake of antigens and microorganisms, a prerequisite for immunological sampling. The molecular features of M cell apical surfaces that promote adherence and transport are crucial for understanding the strategies that pathogens use to exploit this pathway.

Animals↗
PubMed2006

Metagenomic analysis of the human distal gut microbiome.

The human intestinal microbiota is composed of 10(13) to 10(14) microorganisms whose collective genome ("microbiome") contains at least 100 times as many genes as our own genome. We analyzed approximately 78 million base pairs of unique DNA sequence and 2062 polymerase chain reaction-amplified 16S ribosomal DNA sequences obtained from the fecal DNAs of two healthy adults. Using metabolic function analyses of identified genes, we compared our human genome with the average content of previously sequenced microbial genomes. Our microbiome has significantly enriched metabolism of glycans, amino acids, and xenobiotics; methanogenesis; and 2-methyl-d-erythritol 4-phosphate pathway-mediated biosynthesis of vitamins and isoprenoids. Thus, humans are superorganisms whose metabolism represents an amalgamation of microbial and human attributes.

Adult↗
PubMed1975

[Epidemiology, terminology and statistical classification of intestinal infections].

On the basis of critical survey of literature data and analysis of morbidity of intestinal infections in 5 towns of Donbass for 20 years and also of studying 5148 case histories an attempt is made of rational explantation of the causes of growth during the last years of the incidence of Sonne dysentery salmonelloses, escherichioses and other diseases caused by conditionally-pathogenic microorganisms. The importance of improvement of nomenclature and of statistical classification of intestinal infections was demonstrated.

Bacterial Infections↗
PubMed2000

Viability and beta-galactosidase activity of dairy propionibacteria subjected to digestion by artificial gastric and intestinal fluids.

An important criterion to consider in the selection of strains for dietary adjuncts is the ability of the microorganisms to survive the severe conditions of acidity and bile concentrations usually found in the gastrointestinal tract. In the present work, we report the effects of digestions by artificial gastric and intestinal fluids on beta-galactosidase activity and survival of four strains of dairy propionibacteria previously selected by their bile tolerance and beta-galactosidase activity. The strains were exposed to artificial gastric juice at pH values between 2 and 7 and then subjected to artificial intestinal digestion. Both viability and beta-galactosidase activity were seriously affected at pH 2. Skim milk and Emmental cheese juice exerted a protective effect on the parameters tested. The trypsin present in the intestinal fluid inactivated the enzyme beta-galactosidase in strains of Propionibacterium freudenreichii but not in Propionibacterium acidipropionici. Moreover, the presence of bile salts enhanced the beta-galactosidase activity of these strains by permeabilization of the cells during the first hour of exposure. The intestinal transit rate confirmed the permanence of the bacteria in the intestine for long enough to be permeabilized. These results suggest that P. acidipropionici would be a good source of beta-galactosidase activity in the intestine. We also propose a practical and effective in vitro method as a tool of screening and selection of potential probiotic bacteria.

Animals↗
PubMed2005

N-acetylcysteine attenuates bacterial translocation after partial hepatectomy in rats.

BACKGROUND: Translocating enteric bacteria have been suggested as playing a major role in the development of infections after partial hepatectomy. We investigated the effect of N-acetylcysteine (NAC) on bacterial translocation (BT) and intestinal mucosa as the first line of defense against BT. MATERIALS AND METHODS: We compared four groups of eight Sprague-Dawley male rats each: sham, control (partially hepatectomized), partial hepatectomy plus preoperative single-dose NAC, and a fourth that received partial hepatectomy with a preoperative single-dose NAC plus treatment with NAC for 2 days. Microorganism counts of tissues, lung injury score, lung tissue glutathione, and malondialdehyde levels and microscopy of intestinal mucosa were studied at the end of 48 h. RESULTS: Microorganism count in the lung and mesenteric lymph node cultures and lung injury score were significantly higher in the control group when compared with the sham, third, and fourth groups (lung: 9919.6 versus 0.0, 2912.9, 1550.0 cfu/g tissue; mesenteric lymph nodes: 8458.3 versus 0.0, 89.0, 88.9 cfu/g tissue; lung injury score: 3.25 versus 0.5, 1.13, 1.75). In the control group, the villous height of the distal ileal mucosa was significantly shorter than the sham group (65.25 versus 75.25 microm) and the difference from groups 3 and 4 was not statistically significant. Neutrophil infiltration in the distal ileal mucosa of the control group was significantly higher than the sham, third and fourth groups (3.13 versus 0.25, 0.38 and 1.0). CONCLUSIONS: The parenteral use of NAC attenuates bacterial translocation after partial hepatectomy in rats. Attenuation of the lung injury after partial hepatectomy in NAC-treated groups might be attributable to both anti-inflammatory effect and the effect on BT.

Acetylcysteine↗
PubMed1990

[Microbiocenosis and the status of the intestinal mucosa in alkylosing spondyloarthritis].

Intestinal microbiocenosis was examined in 53 patients with ankylosing spondyloarthritis (AS). Of these, 23 had the central and 30 presented with the peripheral form. 34 patients underwent endoscopic examinations (rectoromanoscopy, ileocolonoscopy). As a result, in 74% of cases with the central form of AS and in 80% of cases with the peripheral form of AS, alterations in the intestinal microflora were revealed, which can be regarded as intestinal dysbacteriosis (ID), with dysbacteriosis being more pronounced in patients with the peripheral form. In such patients it manifested by a considerable decrease of the amount of bifido- and lactoflora, which promoted the increment of the amount of opportunistic microorganisms, particularly Klebsiella. Macroscopic signs of nonspecific inflammation of the small and large intestines were identified in 63% of patients with the central and in 67% of those with the peripheral form of AS. Mean-while histomorphological study of biopsy specimens of the intestinal mucosa showed that all the examinees had chronic inflammation of varying degree.

Adolescent↗
PubMed2002

A gene-expression program reflecting the innate immune response of cultured intestinal epithelial cells to infection by Listeria monocytogenes.

BACKGROUND: Listeria monocytogenes is a Gram-positive, facultative, intracellular bacterial pathogen found in soil, which occasionally causes serious food-borne disease in humans. The outcome of an infection is dependent on the state of the infected individual's immune system, neutrophils being key players in clearing the microorganism from the body. The first line of host defense, however, is the intestinal epithelium. RESULTS: We have examined the transcriptional response of cultured human intestinal epithelial cells to infection by L. monocytogenes, which replicates in the host cell cytoplasm and spreads from cell to cell using a form of actin-based motility. We found that the predominant host response to infection was mediated by NFkappaB. To determine whether any host responses were due to recognition of specific virulence factors during infection, we also examined the transcriptional response to two bacterial mutants; actA which is defective in actin-based motility, and prfA, which is defective in the expression of all L. monocytogenes virulence genes. Remarkably, we found no detectable difference in the host transcriptional response to the wild-type and mutant bacteria. CONCLUSIONS: These results suggest that cultured intestinal epithelial cells are capable of mounting and recruiting a powerful innate immune response to L. monocytogenes infection. Our results imply that L. monocytogenes is not specifically detected in the host cytoplasm of Caco-2 cells by intracellular signals. This suggests that entry of bacteria is mediated in the host cell post-translationally, and that these bacteria seek the cytosol not only for the nutrient-rich environment, but also for protection from detection by the immune system.

Bacterial Proteins↗
PubMed1980

[Dissemination of Bdellovibrio acteriovorus in animals and their interaction with the agents of acute intestinal infections].

Cows, horses, pigs and ducks have been found to contain Bdellovibrio bacteriovorus in their intestine and to constantly excrete them with feces into the environment. These microorganisms have not been detected in the feces of man, white mice, frogs and fish. Bdellovibrio, if introduced together with Shigella or after them, prevent the development of keratoconjunctivitis in some of the rabbits. No manifestations of the lytic activity of Bdellovibrio in relation to Salmonella and Vibrio cholerae have been observed in the intestine of white mice and young rabbits.

Animals↗