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PubMed1994

Evidence for natural horizontal transfer of tetQ between bacteria that normally colonize humans and bacteria that normally colonize livestock.

Though numerous studies have shown that gene transfer occurs between distantly related bacterial genera under laboratory conditions, the frequency and breadth of horizontal transfer events in nature remain unknown. Previous evidence for natural intergeneric transfers came from studies of genes in human pathogens, bacteria that colonize the same host. We present evidence that natural transfer of a tetracycline resistance gene, tetQ, has occurred between bacterial genera that normally colonize different hosts. A DNA sequence comparative approach was taken to examine the extent of horizontal tetQ dissemination between species of Bacteroides, the predominant genus of the human colonic microflora, and between species of Bacteroides and of the distantly related genus Prevotella, a predominant genus of the microflora of the rumens and intestinal tracts of farm animals. Virtually identical tetQ sequences were found in a number of isolate pairs differing in taxonomy and geographic origin, indicating that extensive natural gene transmission has occurred. Among the exchange events indicated by the evidence was the very recent transfer of an allele of tetQ usually found in Prevotella spp. to a Bacteroides fragilis strain.

Animals↗
PubMed1989

Production and characterization of monoclonal antibodies to a pilus colonization factor (colonization factor antigen III) of human enterotoxigenic Escherichia coli.

Three monoclonal antibodies (MAbs) to a pilus colonization factor (colonization factor antigen III [CFA/III]) of human enterotoxigenic Escherichia coli (ETEC) were developed and characterized. All of the MAbs isolated belonged to the immunoglobulin G2a subclass. The specificity of these MAbs for CFA/III pili was demonstrated by the immunogold-labeling technique. The presence of more than one epitope in CFA/III pili was suggested. One of the three MAbs appears to recognize a polymeric conformational epitope(s) of CFA/III. CFA/III antigenicity distinct from that of other pilus colonization factors of ETEC was demonstrated by both a bacterial agglutination test and a sandwich enzyme-linked immunosorbent assay using the MAbs. Of the 100 strains of ETEC isolated from persons with traveler's diarrhea, 8% were found to carry CFA/III pili. Two enzyme-linked immunosorbent assay systems which could detect as little as several or 50 ng of CFA/III per ml were developed.

Antibodies, Bacterial↗
PubMed1992

Specificity of colon specific antigen and colon ovarian tumour antigen.

Sections (5 microns thick) from 101 primary adenocarcinomas (including ovarian, colorectal, gastric, breast, oesophageal, prostatic, pancreatic, endometrial and gall bladder) were incubated wtih anticolon specific antigen (CSA) and anticolon ovarian tumour antigen (COTA) antibodies using the peroxidase antiperoxidase technique with positive and negative controls. Anti-CSA positivity was seen in 19 of 20 colonic adenocarcinomas, but it was also seen in a large number of the other tumours. While anti-COTA staining was positive in 16 of 20 colonic adenocarcinomas and 20 of 30 ovarian adenocarcinomas, it was also positive in a large number of the tumours. Anti-CSA and anti-COTA are not adequately specific in the identification of a colonic or ovarian origin of an adenocarcinoma and cannot reliably be applied to the identification of a metastatic adenocarcinoma of unknown primary site.

Adenocarcinoma↗
PubMed1996

Colonic production of butyrate in patients with previous colonic cancer during long-term treatment with dietary fibre (Plantago ovata seeds).

BACKGROUND: Butyrate has antineoplastic properties against colorectal cancer cells and is the preferred oxidative substrate for colonocytes. Like acetate and propionate (short-chain fatty acids; SCFAs), butyrate is produced by colonic fermentation of dietary fibre. METHODS: Twenty patients resected for colorectal cancer were treated with 20 g/day of the fibre Plantago ovata seeds for 3 months, which increased the intake of fibre by 17.9 +/- 0.8 g/day, from basal levels of 19.2 +/- 1.7 g/day; 17 patients completed the study. Faecal samples were obtained on eight occasions, twice before treatment, and monthly three times during and three time after treatment. RESULTS: One month of fibre therapy increased faecal concentrations of butyrate by 42 +/- 12% (from 13.2 +/- 1.2 to 19.3 +/- 3.0 mmol/l; P < 10(-4)), acetate by 25 +/- 6% (P < 10(-4)), propionate by 28 +/- 9% (P = 0.01), and total SCFAs by 25 +/- 6% (P < 10 (-4)). Concentrations were increased during the 3-month fibre treatment but reversed to pretreatment levels within 1 to 2 months after cessation of fibre supplementation. The relative concentration (ratio) of butyrate was not altered owing to a simultaneous increase in acetate and propionate. Faecal pH decreased initially but was normalized after 2 months of fibre supplements. Fibre therapy increased the 24-h productions of butyrate by 47 +/- 10% (P < 10(-4)) and acetate by 50 +/- 7% (P < 10(-4)) in 16.6% faecal homogenates with added P. ovata seeds (20mg/ml), but SCFA productions returned to pretreatment levels after discontinuation of additional fibre intakes. CONCLUSIONS: Oral intake of P. ovata seeds adapted the colonic flora to increase the production of butyrate (and acetate) from this fibre and increased faecal concentrations of butyrate by 42% in patients resected for colonic cancer. The effects depended on continuity of treatment.

Aged↗
PubMed2001

Reconstruction of urinary tract utilizing transverse colon conduit for a cystectomized patient with post-ureterocutaneostomy complications and sigmoid colon cancer.

A seventy-four years old man had been suffering from symptomatic and infectious complications associated with conjoined cutaneoureterostomy following the radical cystectomy for advanced transitional cell carcinoma of the bladder 3 years ago. He underwent urinary reconstruction using transverse colon conduit after diagnostic exclusion of recurrent urothelial tumor in the upper urinary tract, evaluation of performance status and endoscopic examination of the colon. Enteroscopy incidentally revealed he had an early stage adenocarcinoma in his sigmoid colon to be resected, and the resection was followed by the urinary diversion. Postoperatively he is satisfied to be free from urinary complications and frequently visits the outpatient clinic for painful and troublesome ureteral catheter exchange.

Adenocarcinoma↗
PubMed1993

Comparison of the antiproliferative effects of colon mitosis inhibitor, thyroliberin and the somatostatin analog octreotide on rat colonic mucosal epithelial cells.

The effects of colon mitosis inhibitor (CMI), thyroliberin (TRH), and the somatostatin analogue octreotide (SMS 201-995) on rat colonic mucosal epithelial cell proliferation were studied. As an index of cell proliferation the incorporation of bromodeoxyuridine (BrDU) into cell nuclei was used. It was found that all three peptides inhibited the colonic mucosal epithelial cells proliferation, but the time course of inhibition was different. The effect of SMS 201-995 occurred 12 h after the peptide injection, while CMI and TRH suppressed the proliferation after 24 h. These observations suggest that the mechanisms of the antiproliferative actions of somatostatin and of related tripeptides CMI and TRH are different.

Animals↗
PubMed1989

Prevalence of nucleoside diphosphate kinase autophosphorylation in human colon carcinoma versus normal colon homogenates.

The G-regulatory proteins of adenylate cyclase, tubulin, and the ras oncogene protein product require the production of GTP from ATP in order to exert their effects within the cell. This implies that the activity of nucleoside diphosphate kinase (NDPK) plays a major role in the regulation of cellular events requiring GTP and that the level of activity of this enzyme is critical. This report presents a simple method for trapping a specific isozyme of NDPK in its high-energy phosphorylated form (NDPK approximately P) using EDTA and demonstrates that this NDPK approximately P is tenfold higher in malignant colon tumor tissue than in normal colon tissue. This autophosphorylation of the 21,000 and 24,000 Mr subunits of NDPK occurs rapidly at 0 degrees C, will use either [gamma-32P]ATP, [gamma-32P]GTP, or the corresponding 8-azidopurine photoprobes, is intramolecular, displays saturation effects, and is prevented from forming if GTP gamma S is added. Dephosphorylation in the homogenate occurs rapidly upon addition of Mg2+ or any nucleoside-5'-diphosphate. The subunits autophosphorylated in the homogenates are mostly in the soluble phase, and they comigrate with the subunits of pure NDPK from human erythrocytes. Cross-addition of normal and malignant homogenates does not decrease the level of autophosphorylation of NDPK, which indicates that the level of NDPK approximately P may be a quantitative measure of the level of this specific NDPK isozyme form. Assays for NDPK activity show correspondingly elevated levels in the malignant homogenates. Using western blot and photoaffinity labeling techniques, we distinguished the NDPK approximately P subunits from two closely migrating GTP-binding proteins. These were identified as the ras gene protein product and a 20,000 Mr protein, which comigrates identically with ADP-ribosylating factor (ARF). The ARF also comigrates in a tight band that is phosphorylated by [gamma 32P]ATP or [gamma-32P]GTP when Mg2+ is present.

Amino Acids↗
PubMed1989

Functional colonic ultrasonography: normal findings of colonic motility and follow-up in neuronal intestinal dysplasia.

Three types of neuronal intestinal dysplasia (type A, type B, and combination with Hirschsprung's disease) can be distinguished. Functional assessment of the affected bowel segments can be achieved by functional colonic ultrasonography, thus providing exact parameters for further therapeutical procedure. The technique is described. Ten children with neuronal intestinal dysplasia in whom functional colonic ultrasonography was employed and results of their follow-up examinations are reported.

Child↗
PubMed1987

Natural killer cell activity and autologous mixed lymphocyte response of splenic, mesenteric lymph node, and colonic lymphocytes during DMH-induced colon carcinogenesis in the rat.

Two in vitro models of immune surveillance were used to examine the immune status of the gut-associated lymphoid tissue, mesenteric lymph nodes, and spleen during the early stages of 1,2-dimethylhydrazine (DMN)-induced colon tumorigenesis. DMH- and vehicle-treated Fischer rats were sacrificed at one of three time points: one week, two months, or five months after cessation of treatment. Colonic, lymph node, and splenic natural killer cell cytolytic activity toward YAC-1 tumor targets and T-cell response to autologous Ia-induced blastogenesis were measured at each time point. We found little change in natural killer cell activity or T-cell proliferation induced by autologous Ia gene products at these time periods.

Animals↗
PubMed1998

Long pedunculated colonic polyp composed of mucosa and submucosa: proposal of a new entity, colonic muco-submucosal elongated polyp.

We encountered 15 patients with colonic polyps showing histologic features that did not belong to any of the known categories. All polyps were elongated and drumstick-shaped, with lengths of 12 to 160 (mean, 29 mm) mm. Histologically, the polyps were covered with normal mucosa and consisted of edematous, loose, fibrous, connective tissues and dense, fibrous submucosal layers, often showing dilation of blood vessels and lymphatics. Although the mechanism of generation of such polyps remains unknown, their elongation may be caused by intestinal motion. Because this kind of polyp has not been described previously outside Japan, we here introduce a new type of polyp, which we have proposed calling the colonic muco-submucosal elongated polyp.

Adult↗
PubMed1989

An endogenous colon mitosis inhibitor reduces proliferation of colon carcinoma cells (HT 29) in serum-restricted medium.

Extracts of mouse intestine contain a colonic epithelial mitosis inhibitor that has recently been purified and identified as a tripeptide (pGlu-His-GlyOH). In order to elucidate further the biological characteristics of this peptide, the effect of the tripeptide on cell proliferation in a human colon carcinoma cell line (HT 29) was examined. The incorporation of tritiated thymidine was significantly reduced at 20-30 h after addition of the tripeptide. The dose-response relationship was bell-shaped with loss of inhibitory effect at high or low doses. The number of cells were significantly reduced at a peptide concentration of 10(-8) M at 24 h, but not at 48 or 72 h after addition of the peptide. The inhibition was reversible, and was only observed when the cells were grown in a serum-restricted medium (1%). The inhibitory effect was abolished by increasing the serum content to 10% or adding insulin to the medium.

Cell Division↗
PubMed2000

[Actinomycosis of the colon as a rare differential diagnosis of colonic carcinoma].

INTRODUCTION: Abdominal actinomycosis is an uncommon disease. Nevertheless it should be considered in case of unclear tumor-like abdominal masses. METHODS: We report a case of a 49-year-old patient with an intrauterine device. The patient was submitted with a solid and painful tumor in the upper abdomen. After sonography, computerized tomography, gastroduodenoscopy and colonoscopy the preoperative presumptive diagnosis was a carcinoma of the transvers colon invading the abdominal wall. Pathological examination after a right hemicolectomy surprisingly revealed an actinomycosis. RESULTS: Based on this case diagnostic tools and therapeutic options of actinomycosis of the colon are discussed. CONCLUSIONS: This case illustrates the importance to consider the possibility of actinomycosis when finding an unclear abdominal mass. After a surgical excision an abdominal actinomycosis requires antibiotic therapy.

Actinomycosis↗
PubMed2002

Clinical and functional comparison between stapled colonic J-pouch low rectal anastomosis and hand-sewn colonic J-pouch anal anastomosis for very low rectal cancer.

PURPOSE: We investigated intersphincteric resection with hand-sewn coloanal anastomosis, which may be an alternative to standard low anterior resection for very low rectal cancer when stapled anastomosis is technically impossible. METHODS: The present study compared the clinical and functional results of 16 patients who underwent stapled colonic J-pouch low rectal anastomosis (CJLRA) with those of 15 patients who underwent intersphincteric excision and hand-sewn colonic J-pouch anal anastomosis (CJAA). RESULTS: After a median follow-up period of 59 months, local recurrence was found in four patients from the CJAA group, three of whom subsequently underwent curative abdominoperineal resection. Defecatory function 6 and 12 months after surgery did not differ between the groups, although pads were used significantly more frequently in the CJAA group. Anorectal physiologic study before and 12 months after surgery revealed that the internal anal sphincter function was impaired to a larger extent after CJAA than after CJLRA, probably due to the partial or subtotal resection of the internal sphincter, and the anal dilatation during resection and anastomosis. CONCLUSION: Although the prevention of intraoperative tumor implantation and the early detection of local recurrence is of utmost importance, CJAA may be an acceptable sphincter-preserving procedure for selected patients in whom stapled anastomosis is impossible.

Anal Canal↗
PubMed1992

Effect of dietary fiber on colonic bacterial enzymes and bile acids in relation to colon cancer.

Because of the potential significance of colonic bacteria and secondary bile acids in the pathogenesis of colon cancer, the present study investigated the effect of different types of dietary fiber on fecal bacterial enzymes, namely, beta-glucuronidase, 7 alpha-dehydroxylase, nitroreductase, and azoreductase, and on bile acids and neutral sterols in premenopausal women. The subjects consumed 13-15 g of wheat, oat, or corn bran daily for 8 weeks in addition to their normal diet. Stools collected during the normal and fiber diet periods were analyzed for the above constituents. Dietary wheat bran decreased the concentrations of fecal deoxycholic acid, lithocholic acid, 12-ketolithocholic acid, and neutral sterols and the activities of all bacterial enzymes. Oat bran had no effect on secondary bile acids and 7 alpha-dehydroxylase but decreased beta-glucuronidase, nitroreductase, and azoreductase levels. Dietary corn bran increased 7 alpha-dehydroxylase, lithocholic acid, and cholesterol levels and decreased deoxycholic acid coprostanol, cholestenone, nitroreductase, and azoreductase levels. These results show that the modifying effect of dietary fiber on secondary bile acids and bacterial enzymes that may play a role in carcinogenesis depends on the type of fiber consumed.

Adult↗
PubMed1994

Biochemical epidemiology of colon cancer: effect of types of dietary fiber on colonic diacylglycerols in women.

BACKGROUND/AIMS: In view of the potential significance of dietary fat and fiber in colon cancer and the possible indirect involvement of diacylglycerols (DAGs) in the pathogenesis of colon cancer, the effect of types of dietary fiber on fecal DAG in premenopausal women was investigated. METHODS: Forty-eight women consuming a typical western diet provided two 24-hour stool specimens and two sets of preintervention 4-day food records. They were randomly assigned to one of the fiber groups, namely, a wheat, oat, or corn bran supplement. They consumed their control diet plus 13-15 g of dietary fiber from each source for 8 weeks. At the end of the fiber period, each subject provided two 24-hour stool specimens and 4-day food records. Stool samples collected during the two periods were analyzed for total fat and DAG fatty acids. RESULTS: All sources of dietary fiber increased the amount of fecal fat excreted. Dietary wheat bran decreased the concentrations of total DAG and DAG containing lauric acid, myristic acid, palmitic acid, stearic acid, and linoleic acid, whereas oat bran increased the DAG composed of oleic acid and linoleic acid compared with the control diet. Corn bran decreased the DAG containing stearic acid. CONCLUSIONS: These results show that the modifying effect of dietary fiber on DAG depends on the type of fiber consumed.

Adult↗
PubMed1996

Colon cancer screening and the evaluation and follow-up of colonic polyps.

Approximately 150,000 new cases of colon cancer are diagnosed each year, and the mortality rate continues to be greater than 50% of those diagnosed. Screening for colon cancer should be part of the routine health maintenance program of the primary physician. Use of history, physical examination, and sigmoidoscopy is part of a complete program. Colonoscopic removal of polyps reduces cancer risk.

Colonic Neoplasms↗
PubMed1985

Adrenergic factors regulating cell division in the colonic crypt epithelium during carcinogenesis and in colonic adenoma and adenocarcinoma.

Evidence exists implicating adrenergic factors in the control of intestinal epithelial cell proliferation in both normal and diseased states. In this report, attention is focussed on changes in the amine requirements of proliferating cells during the chemical induction of tumours in the colon of mouse. Cell proliferation rates were measured stathmokinetically. Tumours were induced by s.c. injection of dimethylhydrazine (DMH). Results with a series of adrenoceptor agonists and antagonists suggest that there is an alpha 2-adrenoceptor mediated excitatory effect in normal colon but an alpha 2 adrenoceptor mediated inhibitory effect in adenoma and carcinoma. Alpha 1 adrenoceptors, on the other hand, have an inhibitory effect in normal crypts and in adenomas, and an excitatory effect in carcinomas. Beta adrenoceptors have an inhibitory effect in the normal and DMH-treated crypt, and in adenomas, but not in carcinomas. In the crypt epithelium of DMH-treated mice, two regions on cell proliferation, with differing regulatory factors, could be identified. In the upper region of the carcinogen-exposed crypt is a zone where cell proliferation is stimulated by an alpha 2 adrenergic mechanism, thus resembling the basal region of the normal crypt. By contrast, in the basal region of these crypts, cell proliferation is stimulated by an alpha 1 mechanism, thus resembling a malignant tumour.

1,2-Dimethylhydrazine↗