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At least 19 recordsLinked to original sources
PubMed1978

The effects of small intestinal colonization by fecal and colonic bacteria on intestinal function in rats.

The effects of colonic and fecal bacterial proliferation on jejunal function were studied in normal rats and in low-germ rats after intraperitoneal injections of mecamylamine HCl. Jejunal bacteriology, bile salts, ultrastructure, and transport capacity were assessed. Normal rats given mecamylamine for 3 days had increased anaerobic bacteria in the intestinal fluid, and had high concentrations of deconjugated bile salts in the intraluminal contents. Jejunal bacteria were lodged between microvilli without penetrating the cell cytoplasm. However, there was focal cellular damage, including fused microvilli, dilated endoplasmic reticulum, and secondary lysosomes. In the mecamylamine treated normal rats intestinal glucose transport was reduced with an alteration compatible with noncompetitive inhibition. The absorption rates of galactose, fructose, 3-0-methyl-D-glucose, tyrosine, Na, and K were also decreased. In contrast, low-germ mecamylamine-treated rats showed no evidence of either increased anaerobic bacterial proliferation or deconjugation of bile salts, and had none of the fine structural alterations seen in regularly raised rats. Also, the transport of carbohydrates was unaltered. The findings suggest that non-invasive enteric proliferation of colonic and fecal bacterial anaerobes in rats may be associated with deconjugation of bile salts, ultrastructural alterations of the intestinal epithelial cells, and a diminished jejunal transport capacity of carbohydrates and other solutes.

Anaerobiosis↗
PubMed1978

[Restrictive artificial mechanisms in prevention of late complications after small intestine-colon anastomosis].

The experiments on 30 dogs proved that reduplication and semi-invagination serve as restrictive mechanisms before small intestine-colon anastomosis. These procedures slow dowm the evacuation of intestinal contents, interfere with small intestine-colonic outflow, improve digestion and absorption, contribute to the shortening of the time needed for compensation, provide better late results of the right hemicolonectomy.

Animals↗
PubMed2025

Genomic and phenotypic insights into ST164 blaNDM-1-positive Acinetobacter baumannii from intestinal colonization in China.

BACKGROUND: Carbapenem-resistant Acinetobacter baumannii (CRAB) poses a critical global threat, especially in ICUs. Yet, reports on ST164 CRAB harboring blaNDM-1 remain scarce. This study investigates two clinical CRAB isolates, L4773hy and L4796hy, derived from intestinal colonization in Hangzhou, China, focusing on their phenotypic and genomic characteristics as well as the broader transmission of ST164 A. baumannii. METHODS: Bacterial identification was performed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) mass spectrometry. Antimicrobial susceptibility was assessed via agar and broth microdilution. Whole-genome sequencing employed Illumina NovaSeq 6000 and Oxford Nanopore platforms. Resistance genes, insertion elements, transposons, and integrons were detected using ResFinder, PlasmidFinder, VFDB, ISFinder, pdifFinder, and IntegronFinder. Strains were typed by MLST, and a phylogenetic tree was constructed with kSNP3.0. Genetic environment diagrams were generated using Easyfig 2.2.5. RESULTS: Two blaNDM-1-carrying A. baumannii isolates exhibiting extensive resistance to carbapenems, cephalosporins, and fluoroquinolones. Whole-genome sequencing and genetic environment analysis revealed the presence of a conserved structural sequence (ISAba14-ISAba14-aphA-ISAba125-blaNDM-1-bleMBL) on their chromosomes. Phylogenetic and clonal dissemination analysis showed that ST164 CRAB is primarily distributed in China and exhibits clonal spread. Pathogenicity studies indicated that blaNDM-1-positive ST164 strains have enhanced survival under immune pressure but do not display increased virulence in infection models. CONCLUSION: This study provides the genomic and phenotypic characterization of intestinally colonized ST164 blaNDM-1 positive CRAB in Hangzhou, China. The elucidation of the genetic environment of blaNDM-1 further confirms the clonal dissemination of ST164 isolates, highlighting the importance of enhanced surveillance and infection control measures to mitigate the spread of these multidrug-resistant pathogens.

Acinetobacter baumannii↗
PubMed1992

Asymptomatic intestinal colonization by pathogenic Entamoeba histolytica in amebic liver abscess: prevalence, response to therapy, and pathogenic potential.

Since the application of isoenzyme electrophoresis to the study of Entamoeba histolytica, the prevalence and natural history of asymptomatic intestinal colonization in patients with amebic liver abscess (ALA) has not been addressed. We prospectively evaluated this enteric phase in 50 patients with ALA, using two dosage regimens of metronidazole. The overall prevalence of asymptomatic colonization was 72% (36/50). All these isolates, without exception, proved to express pathogenic zymodemes. Despite a 100% clinical response of the hepatic lesions, failure to eradicate the organism from the bowel occurred in 20 of these 36 subjects. During longitudinal posttreatment surveillance, three carriers returned with second bouts of invasive disease: one with dysentery and two with liver abscesses. Thus, in patients with ALA, there is a high prevalence of intestinal colonization with exclusively pathogenic strains, and treatment with metronidazole frequently results in a continued carrier state. These carriers have a propensity for developing recurrent invasive disease and constitute a public health hazard.

Adult↗
PubMed1979

A nosocomial outbreak of infections due to multiply resistant Proteus mirabilis: role of intestinal colonization as a major reservoir.

An outbreak of nosocomial infections involving an unusual strain of multiply resistant Proteus mirabilis (phage type 8888) occurred in 15 patients, 14 of whom were in the surgical intensive care unit at that time. No common source of infection was identified, and person-to-person transmission was the most likely mode of spread. Case-control analysis indicated a significantly increased risk infection related to length of hospital stay (P less than 0.005), number of operations (P less than 0.005), proximity to another case (P less than 0.01), number of antibiotics received (P less than 0.02), and use of a respirator (P less than 0.01). Only the number of operations (P less than 0.01) and proximity to another case (P less than 0.05) remained significant risk factors when related parameters were controlled by multivariate analysis. Thirteen of 14 patients prospectively cultured were colonized by the epidemic organism in the intestinal tract, while rectal carriage preceded infection by the same strain in at least four patients. These data suggest that intestinal colonization may have been an important reservoir for this outbreak, and the findings may explain the unduly prolonged course of intrahospital spread as well as the difficulty encountered in the eradication and control of the outbreak.

Cross Infection↗
PubMed1992

Major outer membrane proteins of Vibrio cholerae and their role in induction of protective immunity through inhibition of intestinal colonization.

Vibrio cholerae O1 organisms belonging to different biotypes and serotypes were shown to express major outer membrane proteins (MOMPs) with subunit molecular masses of 48 to 50, 40 to 43, 35 to 36, 27 to 28, and 20 kDa. Antisera raised against individual MOMPs of a V. cholerae O1 strain recognized MOMPs of corresponding molecular masses in other O1 and non-O1 strains. Serological data also suggested possible differences in the cell surface exposition of these MOMPs. However, no marked differences between V. cholerae cells grown in vitro and in vivo could be noted in respect to the expression or surface exposition of these MOMPs. Of five MOMPs studied in this work, 40- to 43- and 20-kDa cell surface proteins were shown to be of considerable importance, as antisera to these proteins induced significant protection against V. cholerae challenge in the suckling mouse model. Similar protection, although to a lesser extent, was demonstrable with the antiserum to the 27- to 28-kDa protein. These results were corroborated with the Fab (immunoglobulin G) [Fab(IgG)] fragments of the antisera, thereby suggesting that the observed protection induced by anti-MOMP antibodies did not arise as a result of bacterial clumping. Subsequent studies demonstrated that these antisera as well as their Fab (IgG) fragments induced significant inhibition of intestinal colonization of V. cholerae. The 40- to 43- and 27- to 28-kDa proteins appeared to be porinlike, while the 20-kDa protein was found to be antigenically related to TcpA (subunit A of toxin-coregulated pilus). All these results demonstrate the involvement of more than one cell surface antigen of V. cholerae in the induction of protective immunity through inhibition of intestinal colonization of vibrios.

Animals↗
PubMedDate not supplied

[Maternal lactation. II. Intestinal colonization in breast fed newborn infants].

Twenty-three low birth weight infants were studied to establish the role that breast milk plays in the intestinal colonization of the preterm infant, and in the control of epidemic diarrhea due to enteropathogenic E. coli, in nurseries. Twelve of these case were fed breast milk in bottles, and eleven with "humanized" powder cow's milk (NAN M.R.). Bacteriologic studies of feces were performed daily during the first 18 days of life. In 5 cases given breast milk, and in 8 receiving cow's milk, Staphylococcus aureus was isolated. Enteropathogenic E. coli was found in 3 cases with breast milk and in 6 with cow's milk. The finding of other non-pathogenic strains, was similar for both groups, except in the case of Proteus, that was found in 10 cases with breast milk, and in only 3 cases with cow's milk. Breast milk was unable to avoid the colonization by E. coli and in one case, was unable to eradicate this germ. None of the cases fed breast milk had diarrhea, including the three cases with E. coli. In another group, 4 cases developed severe acute diarrhea, due to enteropathogenic E. coli followed by 2 deaths. The results seem to point out that although colonization by enteropathogenic strains of E. coli is not completely avoided, these strains do not cause disease when these infants are fed breast milk.

Asepsis↗
PubMed1992

In vivo effect of cadmium chloride on intestinal colonization of rats by Campylobacter jejuni.

Campylobacter jejuni (10(8) C.F.U) fed intragastrically unto 18 laboratory rats (white whiskers) resulted in colonization of the 18 rats intestines and their eventual excretion of the organism for four months post infection. When 10(8) CFU of C. jejuni was mixed with 10 mu/ml of cadmium chloride (CdCl2) and fed immediately to another set of 18 rats, colonization of rats intestines was greatly reduced and C. jejuni was recovered from two (11%) out of 18 rats and the faeces were positive for C. jejuni for a maximum of 29 days. Six control rats given 1 ml of phosphate buffered saline (PBS) and a second set of another six control animals given 1 ml of PBS containing 10 micrograms/ml of CdCl2 gave negative result for C. jejuni throughout the experiment. This work depicts an in vivo effect of CdCl2 on C. jejuni and may be of importance in the control of C. jejuni colonization in experimental animals.

Administration, Oral↗
PubMed1978

[Inventory relating to roentgen diagnostics of the gastro-intestinal tract (especially of the small intestine, colon, and biliary tract) (author's transl)].

The article describes the authors' experience in their Department in Nijmegen (Holland) with the various types of x-ray equipment: in gastroenterology--especially in the examination of the small intestine, colon, and the bile ducts--and also within the framework of a general roentgenology diagnostics section. Problems of cost are also considered, relating on the one hand to the equipment required in an examination room, and on the other hand to gastroenterological examination. In conclusion, the authors suggest the most suitable type of apparatus to be acquired for a particular purpose.

Digestive System↗
PubMed1992

Antibodies to outer membrane proteins of Vibrio cholerae induce protection by inhibition of intestinal colonization of vibrios.

An antiserum was raised against the outer membrane (OM) preparation of a Vibrio cholerae 01 strain (Classical, Ogawa) and rendered specific for the outer membrane proteins (OMPs) by absorption with its lipopolysaccharide (LPS). The anti-OMP serum showed reactivity against OM preparations of other 01 and non-01 V. cholerae strains in enzyme-linked immunosorbent assay. The antiserum also induced significant protection against V. cholerae challenge in the suckling mouse model. This protection was found to be independent of biotype, serotype as well as serovar of the challenge organism and was demonstrable even at subagglutinating dilutions of antiserum. The Fab (IgG) fragment, prepared from the anti-OMP serum, also induced passive protection in similar experiments. Further studies demonstrated that the anti-OMP serum as well as its Fab (IgG) fragment markedly inhibited the intestinal colonization of a highly colonizing V. cholerae 01 strain A17 (El Tor, Ogawa). These results highlight the importance of V. cholerae OMPs in immunoprophylaxis against cholera.

Animals↗
PubMed1992

Intestinal colonization & production of diarrhoea by enteroadherent-aggregative Escherichia coli.

The ability of HEp-2 cell adherent Esch. coli of aggregative phenotype (EA-Agg EC) to cause diarrhoea and to colonize the bowel of rabbits was studied. Thirty six rabbits were challenged with one of three EA-Agg EC strains (F23A; H766C and F17A-15, 3 and 3 rabbits respectively) or a control strain (K12-15 rabbits) in reversible ileal-tie in adult rabbit diarrhoea (RITARD) model. The animals were sacrificed 72 h post challenge. Severe diarrhoea occurred in greater number of F23A challenged rabbits than the controls (P < 0.05). Mucosal cultures from proximal and distal small intestine and colon yielded about 1000 times more Esch. coli in the test than control rabbits (P < 0.001 in each case). EA-Agg EC were consistently grown from mucosa in the test rabbits who commonly showed mild to moderate villous stunting and grade + to nuclear fragmentation (karyorrhexis) in the small and large bowel epithelium. The control animals had either normal villi or very mild villous stunting. Results comparable to F23A were obtained with the other two EA-Agg EC strains tested in a smaller number of animals.

Animals↗
PubMed1978

Intestinal colonization and virulence of Salmonella in mice.

Within 3 h after oral challenge of mice with Salmonella typhimurium, foci of infection developed in the Peyer's patches of the small intestine. The numbers of organisms in the cecum, although in excess of those found in the small intestine, were not firmly associated with the cecal wall but were present largely in the cecum's contents. The Peyer's patches at first were remarkably incapable of eliminating even small numbers of Salmonella, but at about 7 days after infection developed the ability to eliminate a less virulent strain of S. typhimurium. Selected strains of Salmonella of varied virulence, and hybrid Escherichia coli/Salmonella typhimurium with varied O-antigens, revealed that those of low virulence could multiply within the intestinal Peyer's patches at nearly the same rate as a virulent strain, and the ability to multiply within the Peyer's patches was not dependent upon O-antigen type or smooth lipopolysaccharide. The ability of these strains to adhere to intestinal mucosa in vitro did not reflect on their ability to colonize the Peyer's patches, although strains of high in vitro adhesive ability appeared in greater numbers initially after oral challenge. Anti-O serum, ineffective in reducing the in vitro adhesive ability of virulent S. typhimurium, when given with the oral challenge prevented Peyer's patch colonization but was unable to prevent the appearance of a systemic infection. Anti-H serum, although effective in vitro in preventing adherence, had no effect in vivo. These experiments suggest that adhesiveness is neither essential nor sufficient for the virulence of Salmonella and that the usual development of a systemic infection after colonization of the small intestinal Peyer's patches may be subverted by the presence of O-antibody.

Antibodies, Bacterial↗
PubMedDate not supplied

[Methods for studying the motility in the small intestine, colon and recto-anal area].

Small bowel and colonic motility can be studied either indirectly by the determination of the transit time or directly in recording bowel contractions. Small bowel transit time is usually assessed with the H2-breath test when colonic transit time is mainly determined fluoroscopically in studying the progression of radiopaque markers along the large bowel. Scintigraphic techniques are promising but not routinely used techniques. In the small bowel, gut contractions are recorded with manometric probes. To study colonic movements, electromyography is more usual than manometry. In both cases, whatever the technique employed, the large inter- and intra (topographic and nycthemeral) variability need to be considered for the interpretation of the motor patterns. Rectoanal studies led to consider two aspects: how the rectum acts as a reservoir and anal function. The ability of the rectum to be a reservoir is assessed either by the volume remaining in the rectum during the rectal perfusion with saline or by the determination of the maximal tolerable volume of distension. Manometry and/or electromyography test anal function at rest and during a rectal distension, straining or a voluntary contraction.

Anal Canal↗
PubMed1976

Intestinal colonization with lactobacilli strains in neutropenic patients.

In order to protect granulopenic patients against infections by pathogens from their own digestive tract, large amounts of lactobacilli were given to 5 patients whose intestinal flora had been suppressed by oral antibiotics. In all these cases, lactobacilli failed to prevent spontaneous recolonization of the gastrointestinal tract by enteric bacteria. Six attempts of colonization were made; in spite of the importance of the inoculum administered orally, large numbers of lactobacilli were recovered from stools in only two cases.

Aged↗
PubMed1992

Intestinal colonization potential of turbot (Scophthalmus maximus)- and dab (Limanda limanda)-associated bacteria with inhibitory effects against Vibrio anguillarum.

Of more than 400 bacteria isolated from turbot (Scophthalmus maximus), 89 have previously been shown to inhibit the in vitro growth of the fish pathogen Vibrio anguillarum. The aim of the present study was to investigate the potential of seven of these strains, as well as of intestinal isolates (four strains) from a closely related fish, dab (Limanda limanda), for colonizing farmed turbot as a means of protecting the host from infection by V. anguillarum. In addition, the inhibitory effect of these strains on the pathogen was further studied. Colonization potential was measured by the capacity of the strains to adhere to and grow in turbot intestinal mucus. These parameters were also used to investigate the potential of V. anguillarum to amplify in the turbot intestinal tract. Because of the observed rapid growth of V. anguillarum in intestinal mucus, it can be proposed that the intestinal tract is a site for V. anguillarum multiplication. Strains isolated from the intestine showed greater capacity for adhesion to and growth in fish intestinal mucus than did the pathogen and the skin mucus isolates. All of the isolates released metabolites into the culture medium that had inhibitory effects against V. anguillarum. The results are discussed with emphasis on administering bacteria of host origin to farmed turbot in order to control V. anguillarum-induced disease.

Animals↗
PubMed1976

Gas gangrene infections of the small intestine, colon and rectum.

Thirty-three cases of gas gangrene infections originating from the small bowel, colon, and rectum are reviewed. The distinction between localized and diffuse, spreading, types of infection is made. The overall mortality rate was 42.4% and mortality was highest for infections following elective bowel resections. Treatment consisted of antibiotics and surgical debridement, with hyperbaric oxygen used as adjunctive therapy for the more serious cases. The importance of early recognition of clostridial infection is stressed as the key to improved survival.

Adolescent↗