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PubMed1990

[Fecal contamination with nuclease-positive bacteria as one of the indices of intestinal dysbacteriosis].

A comparative study of the levels of fecal contamination with opportunistic anaerobic nuclease-positive microorganisms was carried out in 114 normal subjects with normal intestinal microflora and in 82 somatic patients with disordered microflora in order to find new integral indicators of disturbed microflora of the intestine; along with routine methods, new techniques were employed. Integral assessment of the intestinal microflora was carried out by scintillation of the total count of facultative anaerobic microorganisms and the share of nuclease-positive bacteria, that yielded nucleic acid depolymerization areas 2 mm or higher from the border of the colonies.

Bacterial Infections↗
PubMed1998

Role of intestinal permeability in monitoring mucosal barrier function. History, methodology, and significance of pathophysiology.

The intestinal barrier function is considered to play an important role in protecting the penetration of luminal antigens, associated with the development of secondary infection and sepsis and the initiation of the multiple organ dysfunction syndrome. The intestinal mucosal barrier against luminal macromolecules and microorganisms consists of both non-immunological and immunological defence mechanisms. The main constituents of the intestinal barrier are the endothelial and epithelial barriers. The epithelial barrier selectively restricts micromolecular permeation and almost completely restricts macromolecular permeation, while the endothelial barrier has a very limited restriction to micromolecules and only partly to macromolecules. Maintenance of the barrier depends on the integrity of cellular plasma membranes and tight junctions, as well as the elaboration of endothelial and epithelial secretory products. Focal denudation of the barrier results in permeation of potentially threatening luminal compounds including antigens, proteases, H+, bacteria and endotoxin, and also other factors chemotactic for inflammatory cells. By initiating inflammation and thus acting on subepithelial tissues, such factors can further influence endothelial and epithelial transport and barrier function. The repair of endothelial and epithelial injury is also complex, and both restitution and enhanced endothelial and epithelial cell proliferation are likely to be important. At present, however, mechanisms for intestinal epithelial and endothelial permeation, their alterations in disease and potential ways to prevent or repair injury, are still not fully elucidated.

Animals↗
PubMed1989

[Therapeutic study of the effect of selective decontamination on microbial overgrowth syndrome of the small intestine].

The microbial overgrowth syndrome of the small bowel (MOS) is characterized by clinically found symptoms of increased metabolic activities of microorganisms existing in a great number in the intestinal juice of these patients. We treated 15 patients who suffered from MOS following a modified scheme of selective intestinal decontamination (SID) with oral doses of BerlocombinR (trimethoprim/sulfamerazin) and polymyxin for three weeks. Comparative investigations of duodenal juices before and after treatment showed unchanged high germ-counts (total aerobes and total anaerobes up to 10(7) germs/ml juice). Only the increase of Clostridium (up to 10(6)/ml) was statistically significant which has to be disapproved. In most of the patients there was no subjective improvement. SID in the examined manner is not able to cure a microbial overgrowth in the upper gastrointestinal tract or to reduce facultatively pathogenic microorganisms.

Adult↗
PubMed1979

Metallothionein: an exceptional metal thiolate protein.

Metallothioneins are unusual, low molecular weight proteins of extremely high sulphur and metabl content. They occur in substantial quantity and in multiple variant forms in parenchymatous tissues (liver, kidney, intestines) of vertebrates and certain microorganisms (Neurospora crassa, yeast). They are though to play a central role in the cellular metabolism of metals such as zinc, copper and cadmium. All mammalian forms studied are single chains with 20 cysteinyl residues among a total of 61 amino acid residues and highly characteristic amino acid sequences. Their most conspicuous common features are seven -Cys-X-Cys- sequences where X stands for an alphatic residue other than Cys. Together with additional cysteinyl residues located elsewhere in the chain and brought into juxtaposition by appropriate chain folding, these dithiol sequences are believed to form the basis of the trithiolate chelating structures typical of most of the six or seven metal-binding sites of the mammalian cadium- and/or zinc-containing metallothioneins. The positions of the cysteinyl residues are preserved in evolution: the copper-containing metallothionein from Neurospora crassa, containing only 25 amino acid residues, has a distribution of metal-binding cysteinyl residues identical to that of the N-terminal portion of the mammalian chains. The detailed physiological role of metallothionein remains to be clarified but its biosynthesis is known to be modulated by nutritional and endocrine factors. Recent evidence suggests that metallothionein is a critical determinant in the homeostasis of zinc.

Amino Acid Sequence↗
PubMed2002

Increased enterocyte production in gnotobiotic rats mono-associated with Lactobacillus rhamnosus GG.

There is increasing scientific and commercial interest in using beneficial microorganisms (i.e., probiotics) to enhance intestinal health. Of the numerous microbial strains examined, Lactobacillus rhamnosus GG has been most extensively studied. Daily intake of L. rhamnosus GG shortens the course of rotavirus infection by mechanisms that have not been fully elucidated. Comparative studies with germfree and conventional rats have shown that the microbial status of an animal influences the intestinal cell kinetics and morphology. The present study was undertaken to study whether establishment of L. rhamnosus GG as a mono-associate in germfree rats influences intestinal cell kinetics and morphology. L. rhamnosus GG was easily established in germfree rats. After 3 days of mono-association, the rate of mitoses in the upper part of the small intestine (jejunum 1) increased as much as 14 and 22% compared to the rates in germfree and conventional counterparts, respectively. The most striking alteration in morphology was an increase in the number of cells in the villi. We hypothesis that the compartmentalized effects of L. rhamnosus GG may represent a reparative event for the mucosa.

Animals↗
PubMed1974

Influences of dietary and environmental stress on microbial populations in the murine gastrointestinal tract.

Aerobic and anaerobic cultural techniques and histological methods were used in a study of the effects of environmental and dietary stress on the indigenous microbiota of the gastrointestinal tract of mice. Mice previously inoculated with Salmonella typhimurium were examined in a similar manner. Three strains of mice (CD-1, Ha/ICr, and C57BL) were used. Control animals previously inoculated with S. typhimurium had low population levels of Salmonella bacteria in the small and large bowel. Mice previously inoculated with Salmonella and then deprived of food, water, and bedding for 48 h harbored high population levels of these bacteria in their small and large bowels. Coliforms increased in numbers in the large bowel of stressed mice inoculated with Salmonella and in the jejunum-ileum and cecum of stressed mice not previously inoculated with Salmonella. Control mice had high population levels of lactobacilli inhabiting the keratinized squamous epithelium of the stomach. Stressed mice showed dramatic reductions in these populations of lactobacilli. Populations of fusiform-shaped bacteria associated with the mucosal epithelium of the cecum and colon in control mice were reduced in stressed mice as determined by microscope examination of histological sections. Total anaerobic counts were similar, however, in both stressed and control animals. Environmental and dietary stress markedly alter the gastrointestinal microbiota in mice. Therefore, such stressful conditions profoundly affect the factors that regulate the localization and population levels of microorganisms in the stomach and intestines.

Aerobiosis↗
PubMed1992

Influence of decontamination on induction of arthritis in Lewis rats by cell wall fragments of Eubacterium aerofaciens. Arthropathic properties of indigenous anaerobic bacteria.

Although the cause (or causes) of rheumatoid arthritis is unknown, many workers have suggested that microorganisms play a part. The intestinal flora in particular has been related to the development of joint inflammation. It has been shown previously that cell wall fragments of several anaerobic Gram positive intestinal bacteria of human origin are arthritogenic after a single intraperitoneal injection in Lewis rats. The part played by indigenous microflora in this model has now been studied by decontaminating Lewis rats before the injection of Eubacterium aerofaciens cell wall fragments. The pattern and severity of arthritis appeared to be comparable in decontaminated and control rats. The second goal of this work was to isolate arthritogenic bacteria from the autochthonous intestinal flora of rats. Only a limited number of bacteria showing a resemblance to arthritogenic strains from human intestinal flora (i.e. E aerofaciens and Bifidobacterium adolescentis) could be isolated. These strains did not induce chronic arthritis after intraperitoneal injection. This may explain why spontaneous arthritis did not develop in Lewis rats.

Animals↗
PubMed2004

Clostridial orthopedic infections: case reports and review of the literature.

Clostridia are anaerobic Gram-positive bacilli that can be isolated from the soil and the intestinal tract of humans. These microorganisms are recognized as the cause of devastating soft tissue infections, such as cellulitis, myositis, and gas gangrene. However, such bacteria may also be involved in various postoperative orthopedic infections, including prosthetic joint infection. We present three clinical cases of clostridial orthopedic infection and review the related medical literature.

Adult↗
PubMed1992

Selective decontamination of the digestive tract as an infection-control measure in intensive care unit patients.

Infection is responsible for a large percentage of morbidity and mortality in intensive care unit (ICU) patients. Conventional infection-control measures are directed at decreasing infection by exogenous sources and have had variable success in significantly reducing nosocomial infection rates. Selective gastrointestinal decontamination with topical nonabsorbable antibiotics attempts to reduce infection by eliminating intestinal mucosal colonization by pathogenic microorganisms. These antibiotics are selectively bactericidal against gram-negative organisms and yeasts, thereby leaving the normal flora (mainly anaerobes) unharmed. In the majority of clinical trials, selective decontamination effectively reduced colonization and infection among ICU patients, with the most significant reductions observed in gram-negative respiratory infections. Resistance to the antimicrobials was not documented in the majority of trials; however, follow-up periods were minimal and may not have been adequate to detect selection of resistant strains. Reductions in infection do not alter mortality; however, patients without significant underlying disease appear to be the subgroup that will most likely benefit.

Anti-Infective Agents↗
PubMed1982

[Etiologic aspects of Reiter syndrome. Role of yersinial infections (author's transl)].

Reiter syndrome occurs as a reaction to various infections, either by intracellular microorganisms (Chlamydia, Mlycoplasma) or by intestinal bacteria (dysenteric bacilli, Salmonella, Campylobacter, Klebsiella, Yersinia). Four personal observations of Reiter syndrome following yersinial infections (Yersinia enterocolitis in two cases and Yersinia pseudotuberculosis in the two other cases) are reported. Data concerning the yersinial etiology of Reiter syndrome are reviewed.

Adult↗
PubMed1998

[Pathogenesis of Bechterew disease].

The etiopathogenesis of ankylosing spondylitis is still incompletely understood. HLA-B27 is important as more than 90% of the patients possess the antigen, but how this genetic marker confers disease susceptibility is yet to be understood. Recent studies of families and twins affected by ankylosing spondylitis have shown that additional non-HLA-B27 genes are necessary for disease development. The exogenous agent initiating chronic inflammation is yet to be identified, but Klebsiella pneumoniae remains a candidate. The microorganism may act through the intestinal canal as more than 60% of the patients exhibit inflammatory changes in the bowel.

Animals↗
PubMed1986

[Biological properties of opportunistic enterobacteria isolated from healthy persons and from patients with intestinal dysbacteriosis].

The comparative study of the signs of pathogenicity in 724 enterobacterial strains and in some species of nonfermenting microorganisms isolated from the feces of 115 somatic patients with intestinal dysbacteriosis and 80 healthy persons (565 strains) has revealed that microorganisms belonging to the same species may essentially differ in their occurrence, in the activity of the enzymes (DNAase, RNAase, phosphatase) which they release into the culture medium, as well as in their capacity to give the positive reaction with Congo red. At the same time, the cultures isolated in cases of intestinal dysbacteriosis have been found to be biologically more active.

Deoxyribonucleases↗
PubMedDate not supplied

[Bacteremia and localized suppurative Salmonella non-typhi infections in the elderly: a study of 4 cases observed at the Ivrea-Castellamonte Hospital].

Over a period of 60 months 137 cases of intestinal and extra-intestinal salmonellosis were registered in the microbiology department of the Ivrea-Castellamonte hospital. The authors conducted a retrospective study relative to the extra-intestinal salmonellosis manifested in elderly patients. In order to carry out such a study the authors considered only patients who were in the hospital, who were over the age of 65, and who had a clinical history different from the usual one of gastroenterocolitis. Out of 61 patients who were in hospital 50 were with complete registration data; 9 (18%) were over 65 years of age. The analysis of the clinical cards permitted the identification of 4 cases with unusual clinical histories due to the presence of serious systemic complications (sepsis with prolonged fever and positive blood cultures) or focal infections in extra-intestinal tissues (abscess of soft tissues, osteomyelitis). The authors focused their attention on these and described the general clinical characteristics of each patient, the type and the position of the isolated microorganism, the manifestations or extra-intestinal complications of the infection and the predisposing factors regarding the same complications. For each patient the essential clinical history and the treatment of the disease have been described. The authors conclude by affirming that in the cases of elderly patients with salmonellosis, apart from those infections in positions different from intestinal one, it would be opportune to consider an antimicrobe treatment also for enteritis infections and cases of asymptomatic infection.

Abscess↗
PubMed2004

Role of probiotics in the modulation of intestinal infections and inflammation.

PURPOSE OF REVIEW: Using microorganisms to influence positively the course of an illness caused by injurious microorganisms is an approach with mounting clinical evidence showing efficacy. Whereas antibiotics will remain an important therapeutic option, there are limitations and problems to their increasing and chronic usage, and probiotics offer a strategy to reduce antibiotic usage. Increasingly, it has become clear that the mechanisms whereby probiotics can impact in intestinal diseases involve a large repertoire of responses. This review summarizes recent findings on how probiotics may effect benefit through interactions with host eukaryotic cells. RECENT FINDINGS: Limiting the access of microbes associated with the development of disease to host mucosal surfaces and altering the responses of host to microbial insults are potential mechanisms whereby probiotics can influence the pathogenesis of disease. Evidence is accumulating that live, viable probiotic organisms diminish accessibility to intestinal epithelial cell; however, the mucosal exclusion is not through direct blockage of shared epithelial receptors between probiotic microbes and pathogenic organisms. Modulation of mucosal defenses such as innate protective mechanisms, enhanced epithelial cell survival, and immune responses have all been shown to have potential in aiding in these actions. Intestinal epithelial cell adherence influences response and, as such, appears to be necessary but may not be wholly sufficient, because soluble bacterial factors have been reported to effect modulation of immune and nonimmune responses of eukaryotic cells. SUMMARY: There is a considerable repertoire of responses potentially responsible for the effects of probiotics, and these responses appear to involve a complex interplay between the microbes of the intestinal tract and the cells of the host. Continued work can be expected to further the understanding of the mechanisms involved, and more work is needed to determine the relative clinical importance of each of the phenomena. These studies are expected to help direct the most efficacious use of probiotics for inflammatory conditions arising from the intestinal tract.

Journal Article↗
PubMed1990

[Effects of a new derivative of 5-alkyl-3N-furanones on the colonization resistance of the intestine in albino mice].

By its antagonistic function normal microflora provides the intestine with resistance to colonization with exogenic opportunistic and pathogenic microorganisms. The drug was effective in inducing a decrease in the intestine colonization resistance which in its turn leads to filling of free ecological niches with exogenic microflora. In this connection the suggestion that specification of a new chemical agent should include along with other criteria its effect on colonization resistance is valid. It was shown with the use of indicator microorganisms that when administered per os in doses of 40 and 80 mg/kg daily for 3 and 6 days, respectively, a new original compound 1929, a derivative of 5-alkyl-3H-furanones, with high antimicrobial activity induced no significant or more pronounced changes in the colonization resistance of the gastrointestinal tract of noninbred albino mice than furagin used as the reference drug.

Animals↗
PubMed1999

A study of infectious intestinal disease in England: microbiological findings in cases and controls.

A study was undertaken to identify the microorganisms and toxins in stool specimens associated with infectious intestinal disease (IID) among cases in the community and presenting to general practitioners (GPs) and in asymptomatic controls. Population based cohorts were recruited from practice lists in 70 practices and followed for 26 weeks (cohort component). Seven hundred and sixty-one cases of IID identified from the cohorts, 2893 cases who presented to GPs in 34 of the practices (GP component), and age/sex matched control subjects (555 and 2264, respectively) submitted stool specimens by post for comprehensive microbiological examination. Campylobacter spp (12.2% of stools tested), rotavirus group A (7.7%), and small round structured virus (SRSV) (6.5%) were the organisms most commonly detected in the GP component. SRSV was identified in 7.0% of cases in the community cohort. No target microorganisms or toxins were identified in 45.1% and 63.1% of cases in the two components. Aeromonas spp, Yersinia spp, and some enterovirulent groups of Escherichia coli were detected as frequently in controls as in cases. The higher frequency of detection of campylobacter, salmonella, and rotavirus among cases who presented to GPs than among those in the community suggests that those pathogens cause more severe illness. No enteropathogens were detected from a large proportion of cases although comprehensive standard methods were used to seek them.

Case-Control Studies↗
PubMed2003

Progress on isolation and short-term ex-vivo culture of highly purified non-apoptotic human intestinal epithelial cells (IEC).

Intestinal epithelial cells (IEC) form the largest surface of the human body and are of pivotal importance to digest and absorb nutrients. Furthermore these cells play a critical role shielding the organism against microorganisms and toxins present in the intestinal lumen. It is therefore not surprising that a large group of researchers take great interest in the study of these cells. However, to date it is a challenge to purify viable primary human intestinal epithelial cells and it has been even more fastidious to maintain IEC in culture ex-vivo as IEC undergo apoptosis within hours due to loss of cell anchorage ('anoikis') following the isolation process. Over recent years the authors aimed to continuously improve the isolation technique for primary IEC, allowing a simple, effective and rapid isolation of highly purified non-apoptotic human IEC. In this study the newly improved method is presented and applied to establish ex-vivo cultures of highly purified, fully viable primary IEC displaying important functional properties, making these cells amenable for ex-vivo research on primary human intestinal epithelial cells.

Apoptosis↗
PubMed2005

Leaky guts and lipid rafts.

The intestinal epithelium functions as a physical barrier separating luminal microorganisms from the underlying immune system. There is compelling evidence that several intestinal diseases are associated with the translocation of commensal bacteria across the epithelial barrier. Recent work has identified a novel mechanism by which normally non-invasive enteric bacteria breach the intestinal epithelium during periods of inflammation.

Bacterial Infections↗