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Rectal colonization with group B streptococcus: relation to vaginal colonization of pregnant women.

Anorectal carriage as a possible primary source of vaginal colonization by group B Streptococcus was investigated. The study was performed during two separate periods and included 789 pregnant women and 422 neonates. Specimens from multiple sites were obtained for culture from all women and infants and were streaked onto blood agar plates containing 8 mug of gentamicin sulfate/ml and 15 mug of nalidixic acid/ml, which allow selective growth of streptococci. Cultures positive for group B streptococci were obtained from 162 (20.5%) of the pregnant women and from 50 (11.8%) of the neonates. Rectal cultures were positive for streptococci in 142 (17.9%) of the women, and vaginal cultures gave positive results in 81 (10.2%). The higher incidence of positive results in rectal as opposed to vaginal cultures (ratio of 2:1) was encountered during all phases of the study. This finding suggests that the gastrointestinal tract may be the primary site of colonization by group B Streptococcus and that vaginal colonization may represent contamination from this source.

Culture Media

Glycoprotein synthesis and secretion in human colon cancers and normal colonic mucosa.

Glycoprotein synthesis and secretion were measured in short-term organ culture of normal and neoplastic colonic mucosa from 11 patients undergoing colectomy for colon cancer. Mucosal explants were incubated for up to 24 hr with [3H]glucosamine, which was incorporated into both explant and secreted glycoproteins. Structural and functional viability was documented by morphological studies that showed excellent preservation of architectural detail and biochemical studies that documented a steady increase in glycoprotein synthesis during 24-hr incubation. The major difference between normal and neoplastic mucosa was a 35% decrease (p less than 0.02) in the incorporation of [3H]glucosamine into tumor explants, as compared to the amount incorporated into normal explants from the same patient. The rate of secretion of radiolabeled glycoproteins into the medium did not differ significantly. Separation of explants into particulate and cytosol fractions showed that the overall decreases in glycoprotein synthesis in tumor explants was primarily due to a marked reduction in particulate glycoprotein synthesis in the cancer tissue.

Adenocarcinoma

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

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

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

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

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

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

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

The role of colon anaerobes in the metabolism of bile acids and steroids, and its relation to colon cancer.

The principle enzymes in the metabolism of both the substituent groups and the nucleus of the bile acids and of cholesterol are reviewed, together with their possible relevence to the etiology of large bowel cancer. Since the incidence of the disease appears to be related to the bile acid concentration and the activity of the 7-dehydroxylase and the delta4-dehydrogenase enzymes, the study of bile acids with a 4,6-dien-3-one structure is strongly recommended.

Anaerobiosis