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At least 55 records · Page 3Linked 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↗
PubMed1979

Nonspecific ulcers of the colon: a case presentation of ulceration of the transverse colon.

This paper describes a patient with nonspecific discrete ulcer of the transverse colon. The lesion was responsible for diarrhea which was cured by conservative resection. These uncommon ulcers, which mimic carcinoma radiographically and were previously thought to be uniformly fatal, may occasionally heal spontaneously. The patient has taken several drugs, some of which may have played a role in the pathogenesis of the ulcer, but the etiology of nonspecific colon ulcer remains uncertain.

Colonic Diseases↗
PubMed1978

Models for investigating the aetiology of cerebral arterial spasm: comparative responses of the human basilar artery with rat colon, anococcygeus, stomach fundus, and aorta and guinea-pig ileum and colon.

1 The pharmacological similarity between human basilar artery and a number of isolated tissues (rat colon, anococcygeus, stomach fundus and aorta and guinea-pig ileum and colon) has been assessed during investigations of the aetiology of cerebral arterial spasm. 2 The responses of each of the six tissues to human normal and abnormal cerebrospinal fluid (CSF) and to human serum were compared with those of the human isolated basilar artery. 3 These studies revealed the presence of a vasodilator factor in CSF from subarachnoid haemorrhage patients and several tissues may be of use for further work in identifying the vasoactive substances in CSF. 4 No tissue displayed exactly the same spectrum of biological reactivity as the human basilar artery. The rat stomach fundus showed the closest similarity and was further studied for similarities in drug-induced responses. 5 The rat stomach fundus, like the human basilar artery, was contracted by 5-hydroxytryptamine, prostaglandin F2alpha and histamine and relaxed by dopamine. However, noradrenaline relaxed the fundus but contracted the basilar artery.

Animals↗
PubMed1979

Scanning electron microscopy of interaction of peripheral blood lymphocytes from colonic cancer patients with human colonic cancer-derived cells; P-4788.

Peripheral blood lymphocytes and the various lymphocyte fractions from patients with cancer of the colon were cultivated with target cells (P-4788) derived from the colon cancer. Changes in the surface ultrastructure during tumor cell destruction were studied by scanning electron microscopy (SEM). P-4788 cells adhering to the coverslip showed various surface activity. The surfaces of some cells were relatively flat; others were smooth or had fine granules. Still other cells were villous, round or had marked blebs. When host lymphocytes were added to the target cells, adhesion of the two cell groups began by many fine projections. After incubation for 6 h, some lymphocytes had adhered to the target cells. Many lymphocytes had adhered to the target tumor cells by 24--48 h incubation. Ultimately the tumor cells became swollen and disrupted. Most lymphocytes adherent to the target cells had few microvilli. Lymphocytes after elimination of phagocytes by carbonyl iron treatment also adhered readily. Some target cells showed adhesion with lymphocytes passed through nylon-wool columns, although the number of lymphocytes adhering was fewer than in the case of lymphocytes not passed through nylon-wool columns. T cells were collected from lymphocytes that form rosettes with SRBC by isolation with NH4Cl. They had markedly elongated microvilli which in places were sparsely scattered and tended to be localized on the side, a finding which suggests loss of cell activity by the time of SEM. Only a few T cells adhered to target cells and they seemed to be T cells without activity. It was thought that there are cytotoxic cells among T cells and that the co-existence of T cells, non-T cells and monocytes caused target cell destruction.

Adenocarcinoma↗
PubMed1978

Acidification of rat colon with lactulose. Its effects on the healing of colonic anastomoses.

Preoperative preparation of rats with lactulose, 2.5 ml/kg of a 52.5% w/w solution, for two days resulted in increased bursting pressure and bursting wall tension of low colonic anastomoses three days postoperatively when compared with unprepared controls (85.8, viz, 36.1 mm Hg and 0.55, viz, 0.19 dynes/cm X 10(-5). After seven days, there was no appreciable difference in the rats with colonic acidification and in the controls.

Animals↗
PubMed1992

Genetic relationship of putative colonization factor O166 to colonization factor antigen I and coli surface antigen 4 of enterotoxigenic Escherichia coli.

Plasmid DNA from two strains of enterotoxigenic Escherichia coli harboring genes encoding coli surface antigen 4 (CS4) and from seven Indian enterotoxigenic E. coli isolates cross-hybridized at low stringency but not at high stringency with two polynucleotide probes derived from the colonization factor antigen I (CFA/I) operon. Low-stringency Southern blot hybridization of PstI-digested plasmid DNA from the seven Indian isolates yielded characteristic restriction fragment patterns, distinct from those of CS4- and CFA/I-associated plasmid DNA. Two of the Indian strains were transformed with a recombinant plasmid harboring the cfaD gene, which encodes a positive regulator of CFA/I and CS4 genes. The cfaD transformants produced large amounts of putative colonization factor O166 (PCFO166) irrespective of whether the nutrient agar contained bile salts, a growth factor otherwise required for adequate PCFO166 expression. A considerable interstrain variation in the level of PCFO166 production could be explained by differences in the proportion of bacteria that were fimbriated, as visualized by electron microscopy. The N-terminal amino acid sequence of PCFO166 fimbrial protein showed a high degree of homology with the corresponding sequences of CFA/I and CS4.

Amino Acid Sequence↗
PubMed1975

Crohn's disease of the colon. III. Toxic dilatation of the colon in Crohn's colitis.

In a group of 160 patients with Crohn's disease involving the colon, there were seven patients with toxic dilatation, four with granulomatous colitis and three with ileocolitis, all successfully treated without mortality. This complications is more common than previously recognized in Crohn's colitis. In Crohn's disease, toxic dilatation is less likely to proceed to perforation of the bowel, because of the nature of the pathology and is more likely to respond to conservative measures: intubation, with decompression, corticotropin, steroids and high-dose antibiotic administration. Although patients do recover from this life-threatening complication with conservative management, the majority of patients, if not all, will ultimately come to surgical excision of the colon. If surgery is mandatory, it should be carried out early, rather than late, in the patient who is failing to respond to medical therapy, certainly before the development of perforation, massive hemorrhage, or gram negative sepsis with shock. The surgical therapy will depend upon the state of the bowel at laparotomy. Thus, an intact bowel in a young patient, would favor subtotal colectomy or proctocolectomy; a sealed perforation, a diverting ileostomy with skin level colostomy decompression as suggested by Turnbull and a free perforation, the minimum adequate procedure which will tide the patient over the early postoperative period. Diverting ileostomy alone has been effective in two of our patients but should be avoided in ulcerative colitis. The critically ill patient with the ominous finding of "disintegrating colitis" and multiple leaks, will require nothing less than total radical excision of the diseased bowel in the hope of immediate salvage.

Adrenocorticotropic Hormone↗
PubMed1976

Studies of introital colonization in women with recurrent urinary infection. VI. Analysis of segmented leukocytes on the vaginal vestibule in relation to enterobacterial colonization.

Segmented leukocytes on the vaginal vestibule were quantitated in 93 specimens from 27 women with recurrent bacteriuria (1.03 times 10(5) plus or minus 4.9 times 10(5) cells per ml.) and compared to 251 specimens from 26 control women who had never had bacteriuria (8.0 times 10(4) plus or minus 1.7 times 10(5)). There was no significant difference (p more than 0.6). Leukocyte counts accompanying colonization with more than 100 Enterobacteriaceae per ml. (6.4 times 10(4) plus or minus 1.0 times 10(5) cells per ml). were no different from those unaccompanied by Enterobacteriaceae (8.7 times 10(4) plus or minus 3.3 times 10(5) cells per ml., p more than 0.9). No distinctive pattern was observed in excretion of vaginal leukocytes during the menstrual cycles of 21 premenopausal, control volunteers.

Adult↗
PubMed1975

Crohn's disease of the colon. V. Retroperitoneal lumbocrural abscess in Crohn's disease involving the colon.

Retroperitoneal lumbocrural abscess occurred in 12 patients of 231 with Crohn's colitis or ileocolitis. Although all patients with this complication fell within the group of 175 ileocolitis patients, at least four originated in fistulous tracts of the colon. Eleven of the 12 abscesses developed spontaneously as the first major complication of the disease. The prominent clinical features included pain radiating down the thigh, hip joint flexion, difficulty in walking, hydronephrosis and hydroureter. Internal and external fistulas were significantly more common in the abscess group of 12 patients than in the 219 patients without retroperitoneal abscess. Radiological evidence of granulomatous disease was found in all patients; fistulous tract formation was characteristic and the development of extraperitoneal gas bubbles, in four patients, pathognomonic of abscess with gast-forming organisms. In the presence of established retroperitoneal abscess, the surgical sequence suggested is drainage synchronous with, or followed by diversion and ultimately definitive resection. Resection with anastomosis should not be carried out in the presence of an acute inflammatory process with frank abscess or free pus communicating with the peritoneal cavity. The spontaneous development of retroperitoneal abscess is a serious development in the natural history of Crohn's (ileo) colitis. It frequently heralds the first of a series of operative procedures to deal with the abscess. It sequels are enterocutaneous fistulas and further extension of the disease process.

Abscess↗
PubMed1976

Colonization of soil by Histoplasma capsulatum: II. Effect of bat guano added to an area of reduced colonization.

Application of bat guano to an area with reduced but detectable colonization by Histoplasma capsulatum had no quantitative effect on the fungus. After seeding the guano treated area and an untreated area with a soil culture of the fungus, a quantitative effect was noted in the treated area but the period of survival did not appear to be extended. Twenty-four months after seeding, the fungus was no longer detectable in the study areas and they have remained negative for more than a year.

Animals↗
PubMed1978

Giant pseudopolyposis causing colonic obstruction. Report of a case seemingly associated with Crohn's disease of the colon.

Gian pseudopolyposis is uncommon and only one obstructive case has previously been reported. In that case the underlying disease was ulcerative colitis while the present case seemed associated with Crohn's disease. Clinically this condition imitates a malignant tumour, and because of the rarity we failed to reach the right preoperative diagnosis in spite of correct colonoscopy and biopsy findings.

Colonic Diseases↗