Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “INTESTINAL MICROORGANISMS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,153 records · Page 64Linked to original sources
PubMed2006

Microbiologicals for deactivating mycotoxins.

Mycotoxins are secondary metabolites of fungi affecting human and animal health. Five classes of mycotoxins are of major concern in animal husbandry, namely aflatoxins, trichothecenes, zearalenone, ochratoxins, and fumonisins. Due to their diverse structure these fungal toxins are able to cause a great variety of acute symptoms in animals. Clay minerals have been used in animal nutrition to bind mycotoxins, but the binders are only very specific for aflatoxins but not for other toxins. A novel strategy to control the problem of mycotoxicoses in animals is the application of microorganisms capable of biotransforming mycotoxins into nontoxic metabolites. The microbes act in the intestinal tract of animals prior to the resorption of the mycotoxins. A Eubacterium (BBSH 797) strain is able to deactivate trichothecenes by reduction of the epoxide ring (CAST, Mycotoxins, Risks in Plant, Animal and Human Systems, Task Force Report 139, Council of Agricultural Science and Technology, Ames Iowa 2003, p. 10.; Binder, E. M., Binder, J., Ellend, N., Schaffer, E. et al., in: Miraglia, M., van Egmond, H., Brera, C., Gilbert, J. (Eds.), Mycotoxins and Phycotoxins--Developments in Chemistry, Toxicology and Food Safety, Alaken, Fort Collins 1996, pp. 279-285). This strain was isolated out of bovine rumen fluid and the mode of action was proven in vitro and also in vivo. Further a novel yeast strain, capable of degrading ochratoxin A and zearalenone was isolated and characterized (Bruinink, A., Rasonyi, T., Sidler, C., Nat. Toxins 1999, 6, 173-177; Schatzmayr, G., Heidler, D., Fuchs, E., Mohnl, M. et al., Mycotoxin Res. 2003, 19, 124-128.) Due to the yeasts affiliation to the genus of Trichosporon and its property to degrade mycotoxins this strain was named Trichosporon mycotoxinivorans (Trichosporon MTV, 115).

Animals↗
PubMed2004

Risk potentials for humans of original and remediated PAH-contaminated soils: application of biomarkers of effect.

Contaminated soils represent a potential health risk for the human population. Risk assessment for humans requires specific methods, which must reflect the peculiarities of human behaviour, physiology and biochemistry with respect to contaminant uptake and processing. Biomarkers of effect or exposure have become an appropriate tool. Organic pollutants influence the expression profile of cytochromes P450 (CYP), and CYP1A1 has been shown to be a suitable biomarker for polycyclic aromatic hydrocarbons (PAH). The latter are widely distributed in soils and constitute an important soil contamination. Upon intake of PAH-contaminated soils, CYP1A1 is induced in various organs of rats and minipigs. Increased CYP1A1-levels in lung, kidney and spleen, after oral soil intake, indicate that contaminants escape the primary duodenal and hepatic metabolism and reach further organs. Dose-response relationships reveal that induction effects are to be expected in children based on known exposure conditions. Generally, CYP1A1-induction does not correlate with results of toxicity tests with lower organisms, performed with the same soils. The organic carbon content is largely responsible for this discrepancy. It severely affects the toxicity of soil bound PAH for microorganisms, but obviously affects the mobilization efficiency for PAH in the gastro-intestinal tract of mammals to a minor extent. Soil remediation by different methods may result in a significant reduction of the PAH content and of toxicity. Ingestion of remediated soils by rats shows, however, that the induction potential for CYP1A1 is only slightly decreased after remediation. This means that the major inducing components resist biological remediation or soil washing and remain in the soil. Because data obtained with experimental animals form the guiding principle for in vitro tests to be developed, the suitability of the animal model used for extrapolations to humans has to be proven. Upon soil ingestion, minipigs show a tissue-specific response pattern, which substantially differs from that of rats, which are widely used as animal models. It is not known which response pattern resembles that of man. In summary, cytochromes P450, in particular CYP1A1, are suitable biomarkers to assess the bioavailability of soil bound contaminants and their effects on mammalian species. There are, however, a number of questions to be answered in order to develop an in vitro test for human risk assessment. This concerns, for example, the identification of the suitable animal model, the identification of biomarkers for other contaminants and concepts to transpose the in vivo data to in vitro technologies or to mathematical modelling.

Animals↗
PubMed2004

Pathogenic Escherichia coli.

Few microorganisms are as versatile as Escherichia coli. An important member of the normal intestinal microflora of humans and other mammals, E. coli has also been widely exploited as a cloning host in recombinant DNA technology. But E. coli is more than just a laboratory workhorse or harmless intestinal inhabitant; it can also be a highly versatile, and frequently deadly, pathogen. Several different E. coli strains cause diverse intestinal and extraintestinal diseases by means of virulence factors that affect a wide range of cellular processes.

Animals↗
PubMed1998

[A case of AIDS complicated with isosporiosis as initial manifestation].

We reported a Thailander patient with isosporiasis accompanied by AIDS. The 34-year-old male, who had been living in Japan for six years, was admitted to our hospital complaining of diarrhea and body weight loss. After admission the patient developed acute renal failure due to dehydration resulting from diarrhea. Laboratory findings on admission showed neither significant microorganisms nor parasite ova in the stool. The patients was given both an intestinal drug and an antibacterial agent, but is vain. Frequent stool examinations disclosed Isospora oocyst in the feaces. Co-trimoxazole was administered resulting in remarkable diarrheal improvement. Renal function was also improved without dialysis. Although isosporiasis is rarely found in Japan, it is stressed that in the AIDS patient with persistent diarrhea who may develop a parasitic disease as did in this case, frequent fecal examinations should be conducted.

AIDS-Related Opportunistic Infections↗
PubMed2000

Epithelial M cells: differentiation and function.

M cells are distinctive epithelial cells that occur only in the follicle-associated epithelia that overlie organized mucosa-associated lymphoid tissues. They are structurally and functionally specialized for transepithelial transport, delivering foreign antigens and microorganisms to organized lymphoid tissues within the mucosae of the small and large intestines, tonsils and adenoids, and airways. M cell transport is a double-edged sword: Certain pathogens exploit the features of M cells that are intended to promote uptake for the purpose of immunological sampling. Eludication of the molecular architecture of M cell apical surfaces is important for understanding the strategies that pathogens use to exploit this pathway and for utilizing M cell transport for delivery of vaccines to the mucosal immune system. This article reviews the functional and biochemical features that distinguish M cells from other intestinal cell types. In addition it synthesizes the available information on development and differentiation of organized lymphoid tissues and the specialized epithelium associated with these immune inductive sites.

Animals↗
PubMedDate not supplied

[A new method of sanation and drainage of the abdominal cavity in experimental generalized suppurative peritonitis].

Elimination of microflora and its products from the abdomena, prevention of commissures, abscesses in postoperative peritonitis are essential for the disease outcome. The sack for this purpose made of polyvinilpirrolidone film (PVF) differs from the standard one by aceptic solution which washes the small intestine, eliminates microflora and products via the tube. This diminishes the count of microorganisms in the abdomena, arrests toxicity, activates immune system.

Abdominal Cavity↗
PubMed2005

[Probiotics for inflammatory bowel disease].

Probiotics are defined as live microorganisms that may beneficially affect the host by improving the balance of the intestinal micro flora. In spontaneous animal models of inflammatory bowel disease (IBD), the influence of the enteric flora on gut inflammatory activity has been demonstrated, as germ free animals do not develop disease. Modification of the activity of the intestinal flora using probiotics has been investigated as a way of controlling IBD. However, there is still considerable work to be done before probiotics can be considered as part of the standard treatment of IBD. Probiotic cocktails should be carefully studied and the individual bacterial constituents evaluated in clinical settings. Several studies are currently underway to assess these issues. Further study of placebo controlled trial testing therapeutic role of probiotic bacteria in human trials is warranted.

Animals↗
PubMed1987

[Skin autoflora in patients with encephalomyelopolyradiculoneuritis with a protracted course].

The deep and superficial skin autoflora has been investigated in 57 patients with encephalomyelopolyradiculoneuritis (EMPRN) characterized by a protracted course. There was a tendency toward an increase in the total colonization of the skin, particularly in the zone of thin intestine projection onto the anterior abdominal wall with the appearance of colonies of microorganisms fermenting mannitol and splitting red blood cells in the amounts exceeding the normal range. These alterations were more marked in deep autoflora and they were evaluated as an indicator of depressed immunobiological reactivity of the body in patients with EMPRN. Skin autoflora in these patients was predominantly presented by a pathogenetic epidermal staphylococcus. The presence of this staphylococcus is considered as a factor of risk and the indicator that the development of staphylococcal infections is highly possible, which makes the "immunological disarmament" in patients with a protracted course of EMPRN even more pronounced.

Adolescent↗
PubMed1993

[The intestines, their role in the critical patient and the concept of bacterial translocation].

The gut is a central organ during critical illnesses that occur as a result of injuries or postoperative infections. After the successful treatment of shock, pulmonary and renal failure, a prolonged septic state emerges, frequently without apparent origin. An immunological host defense failure, associated with the intensive care support that fails to provide the essential amino acid glutamine to the gut, promotes a iatrogenic host invasion by microorganism or soilage by their toxins. This process is called "Bacterial Translocation". The increased permeability of the intestine, coupled with changes in intestinal flora, allows the bowel to serve as a reservoir of pathogens that can enter the portal and systemic circulations and fuel the ongoing septic process. Activating the hepatic reticuloendothelial system, bacterial translocation initiates the Multiple Organ Failure Syndrome. We discuss new therapeutic approaches derived from the aforementioned concepts.

Animals↗
PubMed2004

[Anaerobic intestinal microflora in pathogenesis of autism?].

The present study provides information on differences in the gastrointestinal microflora of children with autism compared with a control group. Special attention was paid to the microbiological characteristic of the new obligate anaerobic microorganisms: Clostridium bolteae sp.nov. and Cetobacterium somerae sp.nov. observed in stools of children with autism. In light of recent publications, the hypothesis of interactions between intestinal microflora - and the brain based on possible alterations in bacterial toxins and other metabolites in the pathogenesis of autism is discussed.

Autistic Disorder↗
PubMedDate not supplied

The effect of ceftriaxone on the anaerobic bacterial flora and the bacterial enzymatic activity in the intestinal tract.

The normal flora of the intestinal tract, mainly consisting of anaerobic bacteria, protects the host against colonization by pathogenic microorganisms. Antimicrobial treatment with ceftriaxone may influence the colonic microflora and as a consequence, the protective effect. Ten healthy volunteers received 1 g of ceftriaxone intramuscularly for five days. This resulted in a significant decrease (p less than 0.05) of the mean cultural counts (+/- SEM) of total anaerobes from 10.67 (0.11) (prior to treatment) to 9.02 (0.45) and 8.97 (0.46) at days 3 and 5, respectively (during treatment). After treatment (days 10 and 15-19), the cultural counts of anaerobes returned to 10.17 (0.16) and 10.44 (0.18), respectively. Bacterial enzymes may serve as an indicator of protective microflora. beta- aspartylpeptidase and deoxycholate hydrolase activity was determined in faecal supernatants of the volunteers and compared with anaerobic culturing. Both enzymatic activities show a significant correlation with the total number of anaerobes present at day 3 of deftriaxone treatment. At day 5 and 8 only beta-aspartylpeptidase showed significant correlations with cultural counts of total anaerobes, Bacteroides spp. or bifidobacteria. At day 15 to 19 (ten to 14 days after treatment) beta-aspartylpeptidase showed only a significant correlation with the number of Bacteroides spp. This indicates that changes in the indigenous bacterial flora during and shortly after treatment with ceftriaxone can be monitored by determination of beta-aspartylpeptidase. Recovery of the intestinal flora is difficult to assess in this manner.

Adult↗
PubMed1987

Impact of Lactobacillus acidophilus supplements on the human oropharyngeal and intestinal microflora.

The influence of Lactobacillus acidophilus supplements on the oropharyngeal and intestinal microflora was studied before, during and after L. acidophilus administration. 10 healthy volunteers participated in the study. L. acidophilus was given as a fermented milk product containing 5 X 10(8)-2 X 10(9) CFU/ml in a dose of 250 ml twice a day for 7 days. Only minor changes in the number of aerobic and anaerobic microorganisms in the oropharynx were observed, with no increase in the number of lactobacilli. In the aerobic intestinal microflora a decrease in the number of Escherichia coli was observed in 6/10 subjects. Concerning the anaerobic intestinal microflora there was a significant increase in the number of lactobacilli in 9/10 subjects within 7 days of L. acidophilus administration. The increase in the number of lactobacilli remained as long as the subjects were consuming the L. acidophilus preparation. Lactobacilli returned to the same level as before the study 9 days after the L. acidophilus administration was stopped. Anaerobic cocci showed a decrease in 4/10 subjects, while the number of other anaerobic bacteria remained relatively constant throughout the observation time. These studies suggest that L. acidophilus in this type of preparation should be taken continuously in order to maintain high levels of lactobacilli in the intestine.

Adult↗
PubMed1998

Identification of bacterial isolates obtained from intestinal contents associated with 12,000-year-old mastodon remains.

Mastodon (Mammut americanum) remains unearthed during excavation of ancient sediments usually consist only of skeletal material, due to postmortem decomposition of soft tissues by microorganisms. Two recent excavations of skeletal remains in anoxic sediments in Ohio and Michigan, however, have uncovered organic masses which appear to be remnants of the small and large intestines, respectively. Macrobotanical examinations of the composition of these masses revealed assemblages of plant material radiocarbon dated to approximately 11,500 years before the present and thought to be incompletely digested food remains from this extinct mammal. We attempted to cultivate and identify bacteria from the intestinal contents, bone-associated sediments, and sediments not in proximity to the remains using a variety of general and selective media. In all, 295 isolates were cultivated, and 38 individual taxa were identified by fatty acid-methyl ester (FAME) profiles and biochemical characteristics (API-20E). The taxonomic positions of selected enteric and obligately anaerobic bacteria were confirmed by 16S ribosomal DNA (rDNA) sequencing. Results indicate that the intestinal and bone-associated samples contained the greatest diversity of bacterial taxa and that members of the family Enterobacteriaceae represented 41% of all isolates and were predominant in the intestinal masses and sediments in proximity to the skeleton but were uncommon in the background sediments. Enterobacter cloacae was the most commonly identified isolate, and partial rDNA sequencing revealed that Rahnella aquatilis was the correct identity of strains suggested by FAME profiles to be Yersinia enterocolitica. No Bacteroides spp. or expected intestinal anaerobes were recovered. The only obligate anaerobes recovered were clostridia, and these were not recovered from the small intestinal masses. Microbiological evidence from this study supports other, macrobotanical data indicating the intestinal origin of these masses. Whether these organisms are direct descendants of the original intestinal microbiota, however, cannot be established.

Animals↗
PubMed1995

Species-specific Mycobacterium genavense DNA in intestinal tissues of individuals not infected with human immunodeficiency virus.

Mycobacterium genavense species-specific DNA was detected in intestinal tissues from two of nine individuals not infected with human immunodeficiency virus. This newly described microorganism is well documented as a causative agent of disseminated infections in AIDS patients. Our results suggest that it may colonize the guts of individuals not infected with human immunodeficiency virus.

Base Sequence↗
PubMed2002

Phylogenetic analysis of the human gut microbiota using 16S rDNA clone libraries and strictly anaerobic culture-based methods.

The human gut microbiota from three healthy subjects were compared by the use of a sequence analysis of 16S rDNA libraries and a culture-based method. Direct counts ranged from 1.9 X 10" to 4.0 X 10" cells/g (wet weight), and plate counts totaled 6.6 X 10(10) to 1.2 X 10(11) CFU/g (wet weight). Sixty to seventy percent of the bacteria in the human intestinal tract cannot be cultured with currently available methods. The 16S rDNA libraries from three subjects were generated from total community DNA in the intestinal tract with universal primer sets. Randomly selected clones were partially sequenced. All purified colonies detected from the surface of the agar plate were used for a partial sequencing of 16S rDNA. On the basis of sequence similarities, the clones and colonies were classified into several clusters corresponding to the major phylum of the domain Bacteria. Among a total of 744 clones obtained, approximately 25% of them belonged to 31 known species. About 75% of the remaining clones were novel "phylotypes" (at least 98% similarity of clone sequence). The predominant intestinal microbial community consisted of 130 species or phylotypes according to the sequence data in this study. The 16S rDNA libraries and colonies included the Bacteroides group, Streptococcus group, Bifidobacterium group, and Clostridium rRNA clusters IV, IX, XIVa, and XVIII. Moreover, several previously uncharacterized and uncultured microorganisms were recognized in clone libraries and colonies. Our results also showed marked individual differences in the composition of intestinal microbiota.

Adult↗
PubMedDate not supplied

[Biocenotic activity of salmonellae of rare groups].

The symbiotic activity of 69 Salmonella cultures of rare groups, belonging to the strains of different origin, with respect to pathogenic and nonpathogenic bacteria, bacilli, Staphylococcus aureus was studied. The study revealed that salmonellae of rare groups were capable of synergetic activity with respect to all test cultures used in this study. The spectrum and manifestation of this property were found to depend on the origin of the strains. The direction of the synergetic activity of salmonellae of rare groups, isolated from the environment, made it possible to suggest the importance of this sign for their survival under unfavorable environmental conditions. Close relationship between the synergetic activity of microorganisms and the clinical course of infection gave grounds for the conclusion on the pathogenic importance of this property and the necessity of its study in the evaluation of the pathogenic potential of microorganisms.

Bacteria↗
PubMed1999

Study of adhesion of Lactobacillus casei CRL 431 to ileal intestinal cells of mice.

It is well known that the cell wall of Lactobacillus casei CRL 431, a strain present in probiotics, presents lectinlike surface molecules. Presence of these molecules stimulates the immune system. Given the role that lectins and lectinlike substances play in the adhesion phenomenon, it is probable that this is an initial stage in the immunostimulation produced by this bacterium. To confirm this, adhesion of this microorganism to exfoliated mouse ileal epithelial cells was studied in vitro. Other L. casei strains isolated from adult human intestines and one of dairy origin were also examined for their ability to adhere to ileal epithelial cells. Another strain, which was included in the present study, was Lactobacillus acidophilus CRL 730. L. casei strains isolated from humans showed good ability to adhere to ileal epithelial cells, whereas L. casei isolated from dairy origin did not. Adhesion was only observed at 37 degrees C and at a pH between 6 and 7.5. The exposure time needed for highest adhesion was 30 min. Presence of lectinlike substances on the surface of L. casei CRL 431 is important to this adhesion phenomenon, since adherence capacity was lost after removal of these substances.

Animals↗
PubMed1986

Antimicrobial induced alterations of the human oropharyngeal and intestinal microflora.

Although the role of the normal oropharyngeal and intestinal microflora is not fully understood, there are evidences that alterations in the flora may have serious consequences. The most common and significant cause of disturbances in the normal microflora is the administration of antimicrobial agents. The microflora can be influenced by antimicrobial agents because of incomplete absorption of any orally administered antimicrobial agent, secretion of an antimicrobial agent by the salivary glands or in the bile, or secretion from the intestinal mucosa. In most cases the influence is not beneficial to the patient because suppression of the indigenous microorganisms often permits potential pathogens to overgrow and cause septic conditions, stomatitis, diarrhoea, or colitis. Antimicrobial agents that influence the normal microflora also promote the emergence of antimicrobial-resistant strains. During the recent years, the impact of different antimicrobial agents on the human microflora has been investigated by our research group. Thus the effects on the oropharyngeal and intestinal microflora by peroral administration of penicillin, bacampicillin, erythromycin, clindamycin, doxycycline, nitroimidazole, norfloxacin and ciprofloxacin have been studied. The impact on the microflora by parenteral administration of ampicillin + sulbactam, azlocillin, aztreonam, piperacillin, cefoperazone, cefoxitin, ceftriaxone, moxalactam, imipenem, nitroimidazole and clindamycin has also been investigated. Pronounced changes were observed in the microflora in patients receiving clindamycin, erythromycin, cefoperazone, ceftriaxone and moxalactam, whereas moderate changes were seen in those patients receiving doxycycline, cefoxitin, aztreonam, ampicillin + sulbactam, azlocillin and piperacillin. Penicillin, bacampicillin, imipenem, nitroimidazole, ciprofloxacin and norfloxacin produced only minor changes.(ABSTRACT TRUNCATED AT 250 WORDS)

Anti-Bacterial Agents↗