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Survival of Lactobacillus species (strain GG) in human gastrointestinal tract.

A newly isolated strain of a species of Lactobacillus of human origin, designated GG (Lactobacillus GG), has been studied to determine its ability to survive in the human gastrointestinal tract. When fed to 76 volunteers as a frozen concentrate or as a fermented preparation in milk or whey, Lactobacillus GG was recovered in the feces of all subjects receiving the fermented milk or whey and in 86% receiving the frozen concentrate when a single fecal specimen was cultured. The organism was also present in the feces of subjects concurrently receiving ampicillin. After terminating feeding of the organism, Lactobacillus GG persisted in the feces of 87% of volunteers four days later and in 33% of subjects seven days later. Lactobacillus GG lowered fecal bacterial beta-glucuronidase activity by approximately 80% in volunteers given the organism for four weeks. These studies demonstrate that Lactobacillus GG can survive and temporarily colonize the human gastrointestinal tract and can affect the metabolic activity of the resident microflora.

Digestive System↗

Acid resistance of Escherichia coli O157:H7 from the gastrointestinal tract of cattle fed hay or grain.

There has been strong debate as to whether feeding cattle hay prior to slaughter will reduce the number and/or virulence of Escherichia coli O157:H7 in the bovine gastrointestinal tract (GIT). This study addressed this issue by comparing numbers, persistence, and acid resistance of generic coliforms and E. coli O157:H7 from various gastrointestinal tract sites of cattle fed grain or hay. Mature Angus steers, doubly cannulated into the rumen and duodenum were inoculated with E. coli O157:H7. Aliquots of digesta from the rumen, duodenum, and rectum were cultured directly or acid shocked (pH 2.0) and then cultured to determine acid resistance. The culture technique used was as sensitive as standard immunomagnetic bead separation protocols. E. coli O157:H7 from hay-fed or grain-fed cattle were similarly acid resistant in all GIT locations. In contrast, generic coliforms from the rumen and rectum of hay-fed animals were more sensitive to an acid shock than coliforms from those GIT locations in grain-fed animals. E. coli O157:H7 colonized the most distal region of the GIT and was not consistently cultured from the rumen or the duodenum. Numbers in the upper GIT did not predict numbers or persistence of E. coli O157:H7 in rectal samples. Grain-feeding or hay-feeding did not affect survival of E. coli O157:H7 in the rumen, nor its passage through the abomasum (pH 2.0) to the duodenum. These data show that generic coliforms behave differently in the bovine host than E. coli O157:H7 and that E. coli O157:H7 acid resistance was independent of animal diet.

Animal Feed↗

THE DEVELOPMENT OF THE BACTERIAL FLORA IN THE GASTROINTESTINAL TRACT OF MICE.

Selective culture media, and equipment for anaerobic incubation of large numbers of specimens, have been developed to facilitate the quantitative enumeration of the various aerobic and anaerobic bacterial species present in the gastrointestinal tract. The evolution of this flora has been followed in young mice from several colonies by cultivating homogenates of the different parts of the gastrointestinal tract at daily intervals from the time of birth to the time of weaning. It has been found that the lactobacilli and anaerobic streptococci become established immediately after birth and persist in large numbers, not only in the large intestine but also in the stomach and in the small intestine. In contrast, the anaerobic bacilli of the bacteroides group become established only after the 16th day; they multiply only in the large intestine but persist in this organ in very large numbers. Other bacterial species become established at different periods of time after birth, exhibit characteristic anatomic localizations, and greatly fluctuate in numbers. In general, the populations of enterobacilli and enterococci decrease precipitously after having reached a maximum level shortly after the beginning of colonization.

Animals↗

Immunohistochemical characterisation of macrophages in human liver and gastrointestinal tract: expression of CD4, HLA-DR, OKM1, and the mature macrophage marker 25F9 in normal and diseased tissue.

This report describes the immunocytochemical characterisation of macrophages in sections of human liver, gastrointestinal tract, and associated lymphoid tissue and the inflammatory lesions of Crohn's disease. 25F9 is an antigen reported to be induced during the maturation of blood monocytes in vitro. The antigen was concentrated in cytoplasmic vesicular structures of isolated gastrointestinal macrophages. Similar labelled cells were observed in the apical regions of lamina propria in both small and large intestine in vivo. Their numbers and size were greatly increased in specimens of colon from patients with melanosis coli. Mucosal inflammatory lesions in specimens from patients with Crohn's disease did not contain 25F9-positive cells. The antigen was absent from giant cells and epithelioid cells in granulomata but was expressed on histiocytes in submucosal microgranulomata. In lymphoid organs, 25F9-positive cells were found in germinal centres, in the dome region of Peyer's patch, and in the medulla, but were largely excluded from T cell areas. In reactive nodes from Crohn's disease patients, the number of labelled cells in germinal centres and T cell areas was greatly increased. 25F9 was absent from the majority of typical liver Kupffer cells, but was expressed on cytoplasmic granules in a minor subpopulation of larger, more rounded cells in the liver. The results suggest that 25F9 is a marker for endocytosis rather than maturation. In parallel sections, resident macrophages of both liver and gastrointestinal tract labelled with Leu 3a/OKT4 (CD4) and with OKIa (HLA-DR antigen) but did not express OKM1 (type III complement receptor). By contrast, OKM1 was present on inflammatory cells, epithelioid cells, and giant cells in mucosal lesions of Crohn's disease.

Antigens, Differentiation, T-Lymphocyte↗

Localization of tissue fibrinolysis in the gastrointestinal tract.

Tissue fibrinolysis in the stomach and intestine of the rat was studied with a histochemical technique. After perfusion of blood vessels to reduce the influence of circulating plasminogen activator and inhibitor fibrinlysis was localized mainly to submucosal arteries and to the serosa of the gastrointestinal tract. This is opposite to previous observations, in which tissue fibrinolysis in the gastrointestinal tract was suggested to be mainly localized to veins. A method for semiquantitative analysis of tissue fibrolysis in the rat stomach is described.

Animals↗

Patients with brain metastases from gastrointestinal tract cancer treated with whole brain radiation therapy: prognostic factors and survival.

AIM: To identify the prognostic factors with regard to survival for patients with brain metastasis from primary tumors of the gastrointestinal tract. METHODS: Nine hundred and sixteen patients with brain metastases, treated with whole brain radiation therapy (WBRT) between January 1985 and December 2000 at the Department of Radiation Oncology, University Hospital Freiburg, were analyzed retrospectively. RESULTS: Fifty-seven patients presented with a primary tumor of the gastrointestinal tract (esophagus: n = 0, stomach: n = 10, colorectal: n = 47). Twenty-six patients had a solitary brain metastasis, 31 patients presented with multiple brain metastases. Surgical resection was performed in 25 patients. WBRT was applied with daily fractions of 2 Gray (Gy) or 3 Gy to a total dose of 50 Gy or 30 Gy, respectively. The interval between diagnoses of the primary tumors and brain metastases was 22.6 mo vs 8.0 mo for patients with primary tumors of the colon/rectum vs other primary tumors, respectively (P<0.01, log-rank). Median overall survival for all patients with brain metastases (n = 916) was 3.4 mo and 3.2 mo for patients with gastrointestinal neoplasms. Patients with gastrointestinal primary tumors presented significantly more often with a solitary brain metastasis than patients with other primary tumors (P<0.05, log-rank). In patients with gastrointestinal neoplasms (n = 57), the median overall survival was 5.8 mo for patients with solitary brain metastasis vs 2.7 mo for patients with multiple brain metastases (P<0.01, log-rank). The median overall survival for patients with a Karnofsky performance status (KPS) >=70 was 5.5 mo vs 2.1 mo for patients with KPS <70 (P<0.01, log-rank). At multivariate analysis (Cox Model) the performance status and the number of brain metastases were identified as independent prognostic factors for overall survival. CONCLUSION: Brain metastases occur late in the course of gastrointestinal tumors. Pretherapeutic variables like KPS and the number of brain metastases have a profound influence on treatment outcome.

Adult↗

[Malignant tumors of the gastrointestinal tract and their early diagnosis].

Malignant tumors of the gastrointestinal tract belong to the main causes of death. The overall 5-years-survival rate is low. Systematic investigations of early gastric cancer and polyps of the colon revealed that asymptomatic carcinomas are detectable and have a definite chance for curative treatment. Mass survey of the population by means of endoscopic or radiological procedures are impossible due to high financial expense. Therefore, other diagnostic tools have to be inaugurated. Besides a maximum diagnostic effort in each individual with gastrointestinal complaints, high risk groups with a significantly increased incidence rate of malignant tumor development have been established. Thorough observation of those persons is necessary as are simple, inexpensive and practicable methods for screening examinations.

Colonic Neoplasms↗

The distribution and ontogeny of gastrin/CCK-, somatostatin- and neurotensin-immunoreactive cells in the gastrointestinal tract of the chicken.

The distribution and time of appearance of cells with gastrin/CCK-, neurotensin- and somatostatin-like immunoreactivity were studied in samples from eight regions of the gastrointestinal tract of chick embryos from 11 days of incubation to hatching. No immunoreactive cells were found in any region at 11 days of incubation. Somatostatin- and neurotensin-immunoreactive cells appeared for the first time in the proventriculus, pyloric region and duodenum at 12 days of incubation with cells immunoreactive for neurotensin occurring in the rectum at the same stage. Gastrin/CCK-immunoreactive cells were detected in the small intestine first at 14 days and in the pyloric region two days later. Cells immunoreactive for somatostatin and neurotensin appeared in the upper and lower ileum at 14 days of incubation for the first time; neurotensin-immunoreactive cells, present in the caecum at 14 and 16 days, were rare. Cells of all three types were plentiful in the pyloric region by 17 1/2 days of incubation. No immunoreactive cells were detected in the gizzard at any stage studied. Endocrine cells were present in the relatively undifferentiated surface epithelium which occurs throughout the gastrointestinal tract of chick embryos at 12 days of incubation. Thereafter cells of all three types were detected in the glandular epithelium at or very soon after morphogenesis and differentiation of the latter had occurred.

Animals↗

Screening of bacteria from the cattle gastrointestinal tract for inhibitory activity against enterohemorrhagic Escherichia coli O157:H7, O111:H-, and O26:H11.

A quick and reproducible microgel plate assay was adapted to screen bacteria from cattle gastrointestinal tracts for production of compounds inhibitory to the growth of three enterohemorrhagic Escherichia coli (EHEC) serotypes: O157:H7, O111:H-, and O26:H11. The inhibitory activity of 309 bacteria, isolated on several agar media, was assessed by a microgel assay performed in 96-well microtiter plates. Fifty-three isolates secreted inhibitory compounds with a molecular weight of less than 1,000. In 12 isolates, the inhibitory activity was attributable to compounds other than lactic or acetic acid. These compounds were highly heat tolerant, with varying sensitivity to digestion by proteolytic enzymes. The inhibitory isolates were identified as lactic acid-producing bacteria on the basis of a combination of analyses, including 16S-rDNA restriction fragment length polymorphisms, 16S-rDNA gene sequences, and fermentation end products. The lactic acid bacteria of ruminants may contain antibacterial compounds not yet described. Naturally occurring populations of lactic acid bacteria may have potential as probiotics, to reduce the carriage of EHEC in the gastrointestinal tract of ruminants.

Animals↗

HPC-1/syntaxin-1A activity in the enteric nervous system of developing rat gastrointestinal tract.

The HPC-1/syntaxin-1A antigen was originally identified as a neuron-specific membrane protein in the central nervous system. The presence of HPC-1 antigen in the nervous system of the fetal rat gastrointestinal tract was immunohistochemically demonstrated using the antibody against HPC-1 to clarify the role of this protein in the development of the enteric nervous system. Rat gastrointestinal tract from 14-, 16-, 18-, and 20-day fetuses and adults were immunohistochemically examined for HPC-1 antigen by light microscopy. Acetylcholinesterase (AchE) activity was also examined as a comparison. HPC-1 activity was first detected on 18th day of gestation. AchE activity was first detected at the Auerbach's plexus of the esophagus on the 16th day of gestation. The presence of HPC-1 in the developing rat intestine revealed that the HPC-1 antigen may be a good indicator for expressing the maturation of enteric nervous system in the development of the enteric nervous system.

Acetylcholinesterase↗

Autoradiographic localization of 2[125I]iodomelatonin binding sites in the gastrointestinal tract of mammals including humans and birds.

In-vitro autoradiography was utilized to compare the distribution of 2[125I]iodomelatonin binding sites or putative melatonin receptors in the gastrointestinal tracts of humans, guinea pigs, mice, rats, hamsters, rabbits, ducks, chickens, pigeons, and quail. In humans, binding was detected in the mucosa of the colon, caecum, appendix, and on their blood vessels but not in the ileum. In the other mammals, significant binding was only demonstrated in the mucosa of the rabbit rectum, mouse colon, mouse rectum, and guinea pig ileum. The distribution of 2[125I]iodomelatonin binding in the avian gut varied with species. In the esophagus, binding was present in the lamina propria and blood vessels of all four birds. However, only the lamina propria of the chicken and quail proventriculus and ventriculus showed positive binding. For the duodenum and ileum, binding was very strong in the duck lamina propria, weak in the chicken lamina propria, and absent in the quail. In contrast, the pigeon muscle layer was weakly positive. The most striking species difference was found in the caecum where the duck lamina propria showed very strong binding, while the chicken lamina propria was only weakly positive. Conversely, the caecal muscle layer was strongly positive in chicken and quail but negative in duck and pigeon. In the rectum, a similar but less intense pattern of distribution was observed. The tremendous diversity in the distribution of 2[125I]iodomelatonin binding sites in the gastrointestinal tract is in accord with the hypothesis that melatonin may serve different functions in the gut of different species.

Animals↗

Detection of gastrointestinal tract events from multichannel intraluminal impedance measurements.

Investigation of Gastrointestinal tract (GIT) using multichannel intraluminal impedance technique (MII) is presented. The MII traces have large variations which correspond to the occurrence of certain activity that causes the impedance to change. A technique to detect the tract events from MII data is developed using wavelet transform. The resulting transformed signals are used to detect the occurrence of GIT events and to classify the events as swallow, reflux, or gas reflux. The technique is also used in estimating reflux event duration and the bolus velocity.

Electric Impedance↗

Leiomyoblastomas and their relationship to other smooth-muscle tumors of the gastrointestinal tract. An electron-microscopic study.

Twelve cases of gastrointestinal leiomyoblastoma were studied by electron microscopy, and the findings were compared with those in 12 cases of leiomyoma and nine cases of leiomyosarcoma of the gastrointestinal tract. All of the "classic" ultrastructural features of smooth-muscle tumors, including subplasmalemmal dense patches, pinocytotic vesicles, cytoplasmic microfilaments and dense bodies, and focal basement membrane formation, were present in the leiomyoblastomas ; however, extensive sampling was commonly necessary to demonstrate such findings. In contrast, these features were more prominent in leiomyomas and leiomyosarcomas.

Adult↗

Distribution of bombesin binding sites in the rat gastrointestinal tract.

In an attempt to identify potential target sites for the satiety action of bombesin (BN), the distribution and pharmacological specificity of bombesin binding sites were examined in the rat gastrointestinal tract by in vitro autoradiography utilizing (125I-Tyr4) bombesin. Specific BN binding was localized to the circular muscle level of the gastric fundus and antrum, submucosal layer of the small intestine and longitudinal and circular muscle and submucosal layers of the colon. Pharmacological studies indicated that gastrin releasing peptide (GRP), Ac-GRP20-27 and BN-like compounds, litorin and ranatensin, inhibited the binding of (125I-Tyr4)BN with high affinity while compounds which lacked COOH-terminal homology with BN demonstrated a low affinity for BN binding sites. The wide distribution of BN binding sites in the gastrointestinal tract provides a number of potential sites for the mediation of the satiety action of BN.

Animals↗

[Techniques of anastomoses in the gastrointestinal tract].

The authors analysed 718 operative interventions in which gastrointestinal anastomoses were formed at various levels of the gastrointestinal tract. It was established that the more distal the anastomosis is, the greater the risk of its incompetence and a fatal outcome due to it are. The advantages of the "closed" method for forming the anastomosis in operations on the ileum and colon were revealed. A method for creating anastomoses by the closed technique with a single-row suture is suggested.

Anastomosis, Surgical↗

Macrophage migration inhibitory factor (MIF) -173G/C promoter polymorphism influences upper gastrointestinal tract involvement and disease activity in patients with Crohn's disease.

BACKGROUND: Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine with increased expression in inflammatory bowel disease. The aim of the study was to analyze the role of the MIF -173G/C single nucleotide polymorphism in Crohn's disease (CD). METHODS: Using restriction fragment length polymorphism analysis, genomic DNA of 198 patients with CD and 159 unrelated controls was analyzed for the -173G/C SNP in the MIF promoter region. Colonic MIF mRNA expression was measured by quantitative polymerase chain reaction (PCR), serum MIF levels by enzyme-linked immunosorbent assay (ELISA). RESULTS: Thirty-six of the 146 G/G wildtype carriers (24.7%) but only 3 of the 45 G/C heterozygotes (6.7%) and only 1 of the C/C homozygotes (14.3%) were diagnosed with upper gastrointestinal tract involvement (P = 0.009, odds ratio [OR] = 0.22, 95% confidence interval [CI], 0.06-0.75 for wildtype versus hetero- and homozygous carriers). This result was confirmed in a second prospective study, in which all patients diagnosed with upper gastrointestinal involvement (n = 13) were G/G wildtype carriers (P = 0.01 versus controls). All patients (n = 12; 100%) with a Crohn's disease activity index (CDAI) > 300 were G/G wildtype carriers compared to only 65.6% wildtype carriers in the group with a CDAI < 150 (P = 0.016). MIF is expressed in the colonic mucosa of CD patients and intestinal epithelial cells but its mRNA expression does not correlate with the degree of inflammation and is not upregulated by proinflammatory cytokines. In CD, MIF serum levels are not influenced by the MIF -173G/C polymorphism. CONCLUSIONS: The MIF -173G/C polymorphism appears to be a factor contributing to a particular CD phenotype characterized by protection against upper gastrointestinal tract involvement and severe disease activity.

Adolescent↗

Systemic availability of the active metabolite hydroxy-fasudil after administration of fasudil to different sites of the human gastrointestinal tract.

This study evaluated the gastrointestinal absorption of fasudil, a novel Rho kinase inhibitor for the treatment of stable angina, at different sites using remote-controlled capsules and assessed the feasibility of developing an extended-release formulation. Ten healthy male volunteers were enrolled, and 8 subjects completed this single-dose, open-label, randomized, 5-way crossover study. Forty milligrams of fasudil HCl was administered as solution to the distal ileum and ascending colon, as powder to the ascending colon, and orally as an immediate-release tablet and solution. All treatments were well-tolerated and no serious adverse events were observed. The mean systemic availabilities of M3 relative to the oral solution were 1.04 (distal ileum, solution), 1.14 (ascending colon, solution), 1.27 (ascending colon, powder) and 1.04 (oral tablet), indicating similar systemic availability of M3 after administration of fasudil HCl to different gastrointestinal sites. The results suggest that development of a once-a-day extended-release formulation for fasudil HCl should be readily achievable.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗

Tachykinins stimulate lipid peroxidation mediated by free radicals in gastrointestinal tract of rat.

Tissue concentrations of malondialdehyde in the gastrointestinal tract of the rat were quantified as indicators of lipid peroxidation and tissue damage after challenge with tachykinins and after pretreatment with allopurinol. Neurokinin A, neurokinin B, and substance P given intravenously during 30 min increased the production of malondialdehyde in the stomach, duodenum, jejunum, and colon in a dose-dependent manner at doses from 100 to 400 pmol/kg/min (P < 0.05-0.01). However, the stomach seemed less responsive to the tachykinin challenge. For comparison, a similar dose-dependent increase of malondialdehyde was found in the liver and lung, with more pronounced effects of neurokinin B (P < 0.05-0.01). Pretreatment with allopurinol, 10 mg/kg, significantly reduced malondialdehyde responses to tachykinin challenge in intestinal tissues (P < 0.001). In conclusion, elaboration of malondialdehyde is suggested to reflect the ability of gastrointestinal tissues to react to tachykinins at high concentrations with liberation of free radicals as part of an inflammatory reaction.

Allopurinol↗