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At least 19 recordsLinked to original sources
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↗
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↗
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↗
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↗
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↗
PubMed1977

Intestinal colonization and adhesion by enteroxigenic Escherichia coli: ultrastructural observations on adherence to ileal epithelium of the pig.

Colonization of pig ileum by enterotoxigenic Escherichia coli that were enteropathogenic for pigs but that lacked K88 antigen (K88-) resulted in morphological characteristics similar to those reported for K88+ strains. Strains of enterotoxigenic E. coli from three different K88-serotypes adhered to the villous epithelium. In sections examined by transmission electron microscopy, adherent bacteria were separated from each other and from epithelial microvilli by peribacterial electron-lucent regions. The enterotoxigenic E. coli had appendages that extended into these regions. The appendages were morphologically characteristic for each strain. It is possible that these appendages were pili, polysaccharide K antigens, or structures resulting from some interaction between pili and polysaccharide. Certain pili or pilus-like structures may be virulence attributes that facilitate adhesion of enterotoxigenic E. coli to the intestinal epithelium.

Animals↗
PubMed1979

Dietary Na+ effects on transepithelial transport of NaCl by hen (Gallus domesticus) lower intestine (colon and coprodeum) perfused luminally in vivo.

The colon and coprodeum of anaesthetised laying hens was perfused luminally with solutions of varying compositions, to elucidate the influence of three levels of dietary NaCl and of luminal NaCl concentrations on coprodeal and colonic transport of NaCl. Net Na+ and Cl- absorption rates were increased in response to low dietary Na+ levels and higher luminal NaCl concentrations. Net Na+ absorption was always against the prevailing electrochemical gradient, saturably dependent on luminal Na+ concentrations in low Na+ diet birds, and linearly dependent on luminal concentrations in medium and high Na+ diet birds. Net Cl- absorption was usually down its electrochemical gradient. The Cl- flux rates were strongly linearly dependent on Na+ flux rates, and statistically this relationship could account for all significant variation of Cl- fluxes associated with dietary and perfusate treatments. Transmural electrical potential differences were invariably serosa positive, and partly correlated with Na+ fluxes.

Animals↗
PubMed1979

Transepithelial transport of K+, NH4+, inorganic phosphate and water by hen (Gallus domesticus) lower intestine (colon and coprodeum) perfused luminally in vivo.

The colon and coprodeum of anaesthetised laying hens was perfused luminally with solutions of varying compositions to elucidate the influence of three levels of dietary Na+ and of luminal fluid composition on transport of electrolytes and water. Net rates of secretion of K+ and absorption of NH4+ were increased in response to dietary Na+ depletion and increased luminal Na+ concentrations, but these fluxes were linked to Na+ transport and no dietary or perfusion treatment effects could be detected on them independently of effects on Na+ flux. Similar results were found for Na+-linked water absorption from isosmotic perfusates. Serosal-mucosal net osmotic flow with Na+-free perfusates was significantly reduced by Na+-depletion, but no significant dietary effect could be detected on the serosal-mucosal osmotic permeability coefficient. The reflexion coefficient was effectively unity. Mucosal-serosal inorganic phosphate flux was small. The flux was independent of Na+ flux and dietary Na+ levels, and apparently facilitated by serosalmucosal osmotic flow. The data allowed determination of the absorption/secretion in coprodeum and colon of the ions investigated, as compared to the renal excretion rate.

Ammonium Chloride↗
PubMed1978

"Small intestinal type" and "colonic type" intestinal metaplasia of the human stomach, and their relationship to the histogenetic types of gastric adenocarcinoma.

Intestinal metaplasia in the non-tumour bearing parts of the gastric mucosa was demonstrated in 24 cases in a material consisting of 27 consecutive patients operated for carcinoma of the stomach. Two mucin histochemical types of intestinal metaplasia could be identified. 1) "Small intestinal type" which was present in all 24 cases, and which was by far the most dominating type. 2) "Colonic type" which occurred in small foci in the gastric mucosa of 11 cases, and which was significantly more frequent in stomachs bearing tumours of presumed intestinal histogenesis, than in those bearing tumours of presumed non-intestinal histogenesis.

Adenocarcinoma↗
PubMed1979

Effects of age, ambient temperature, and heat-stable Escherichia coli enterotoxin on intestinal transit in infant mice.

Some interrelationships among age, ambient temperature, intestinal transit, and enterotoxigenic Escherichia coli infection were studied in an infant mouse model. The transit of dye in the small intestine was accelerated during the response to heat-stable E. coli enterotoxin. Transit in the small intestine of normal mice accelerated with increased age (from less than 17 h to 8 days old) and accelerated with increased ambient temperature (from 25 to 37 degrees C). Transit was more rapid in the jejunum than in the ileum throughout the range of experimental conditions studied. E. coli strains that do not produce any of the pili known facilitate intestinal colonization were cleared from the small intestine more rapidly at 37 degrees C than at 25 degrees C. This clearance was thought to be due to accelerated transit at the higher temperature. In contrast, a strain of E. coli that produces K99 (pili previously shown to facilitate intestinal colonization in other species) was not cleared from the small intestine and colonized more intensively at 37 degrees C than at 25 degrees C. Intensified colonization by this strain was thought to be due to increased production of K99 at the higher temperature. It was suggested that sluggish intestinal transit may also be characteristic of the neonates of other species and be one of the factors predisposing them to intestinal colonization by enteropathogens. It was speculated that this predisposition may be enhanced if the neonates are chilled. However, the effect of ambient temperature on intestinal transit in homeothermic neonates such as pigs, calves, and humans may be different from that in mice because neonatal mice are poikilothermic.

Aging↗
PubMed2026

Genomic Characterization of Antimicrobial Resistance and Virulence in ST11 Carbapenem-Resistant Klebsiella Pneumoniae Colonizing the Intestinal Tract of Elderly Inpatients.

BACKGROUND: This study aimed to elucidate the molecular epidemiology and virulence characteristics of ST11 carbapenem-resistant Klebsiella pneumoniae (CRKP) colonizing the intestinal tract of elderly inpatients in the Chongzhou region, providing a basis for controlling the transmission of such resistant bacteria in high-risk populations. METHODS: CRKP strains isolated from the intestines of elderly inpatients in this region between January 2023 and June 2024 were collected. ST11 strains were identified via multilocus sequence typing (MLST). Whole-genome sequencing, antimicrobial susceptibility testing, and string test, serum killing, biofilm formation, capsular polysaccharide quantification were employed to characterize their resistance genes, virulence genes, and molecular typing profiles. RESULTS: Among 58 CRKP isolates, 17 (29.3%) were ST11. ST11-KL64 was the dominant clone (70.6%). All isolates carried the carbapenemase gene bla KPC-2 and exhibited extensive drug resistance, with tigecycline retaining the highest susceptibility (64.7%). The yersiniabactin system genes (ybtS, fyuA, entB) were universally present, whereas the aerobactin gene cluster (iucABCD-iutA) was detected in only 17.6% of isolates. The virulence regulator rmpA2 was incomplete in all carriers. The hypermucoviscosity phenotype was observed in 35.3% of isolates, which correlated with serum resistance in some strains. Biofilm formation was variable. The mortality rate among colonized patients was 35.3%. CONCLUSION: The ST11-KL64 clone is dominant among CRKP strains colonizing the intestinal tract of elderly patients in this region. This clone universally carries the bla KPC-2 gene conferring carbapenem resistance and exhibits a unique virulence gene profile characterized by a low carriage rate of classical hypervirulence markers and an incomplete rmpA2 regulator gene. This finding clarifies the local epidemic status of this clone and underscores the importance of implementing active surveillance and targeted prevention strategies for high-risk populations.

KL64 serotype↗