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PubMed1979

Diurnal variation in proliferative compartments and their relation to cryptogenic cells in the mouse colon.

The depth of the crypts in mouse descending colon varied diurnally, between twenty-six cells at 24.00 hours and thirty-eight cells at 12.00 hours. Cell loss from the colon was greatest immediately before the maximum faeces production, at the beginning of the dark period. The labelling index of the colon also changed, from 9% at 20.00 hours to 16% at 12.00 hours. The greatest variation in labelling index occurred at the top of the zone of proliferative cells, between the ninth and eighteenth cell position up the crypt. In this region a synchronized cohort of about forty cells apparently entered S phase once a day. Although the length of the proliferative zone doubled at 12.00 hours, that of the non-proliferative zone remained fairly constant all day. The number of cryptogenic cells per crypt was estimated by comparing single and split-dose X-ray survival curves. This gave a mean value of two cryptogenic cells per crypt. Crypts rarely regenerated from the base after irradiation. The cryptogenic cells probably lay between cell positions Nos 9 and 18 up the crypt and probably did not function as stem cells in the normal crypt.

Animals↗

PubMed1978

Localization of carbohydrate components in rat colon with fluoresceinated lectins.

Cryostat sections of rat descending colon were studied by fluorescence microscopy after exposure to conjugates of fluorescein isothicoyanate with lectins from Glycine max (soybean), Triticum vulgaris (wheat germ), Ricinus communis (castor bean), Ulex europaeus, (gorse), Dolichos biflorus (horse gram) and Canavalia ensiformis (concanavalin A) (Jack bean). No two lectins showed identical patterns of fluorescence. FITC-conjugates of soybean and D. biflorus lectins reacted strongly with the mucus present in the crypt lumens and with the surface (as well as cytoplasm) of the epithelial cells suggesting that these sites are rich in terminal, non-reducing, N-acetylgalactosamine residues. Wheat germ, R. communis, U. europaeus and concanavalin A-FITC conjugates did not stain mucus but showed fluorescence in the cytoplasm of absorptive cells as well as in the lamina propria and submucosa. The FITC-R. communis conjugate also reacted with structures in the apical portion of epithelial cells that may correspond to the Golgi apparatus.

Animals↗

PubMed1999

Microdeletion of chromosome sub-band 2q37.3 in two patients with abnormal situs viscerum.

We report on two cases of microdeletion of chromosome sub-band 2q37.3 with abnormal situs viscerum. The first patient had dextrocardia, duodenal and jejunal atresia, and an abdominal hernia. The liver was in the left upper quadrant, stomach in the right upper quadrant. In contrast anema the ascending colon was in the left, and descending colon on the right, with an area of atresia in the mid-jejunum. The second patient had malrotation and malposition of large and small bowel, with most of the bowels positioned above the liver and spleen. There was incomplete rotation of the cecum. The right kidney was malrotated and mal-positioned. The finding of 2q37.3 deletion in both patients implies that a locus or loci involved in the development of normal body situs lies within this chromosome region. Molecular cytogenetic evaluation for a possible 2q37.3 deletion should be considered in patients with abnormal situs viscerum.

Adolescent↗

PubMed1995

Is mechanical bowel preparation necessary before primary colonic anastomosis? An experimental study.

UNLABELLED: The necessity of preoperative or intraoperative mechanical bowel preparation of the colon, before primary anastomosis, has been recently challenged in clinical elective and emergency situations. PURPOSE: This experimental study in dogs investigated the safety of segmental resection and primary anastomosis in the unprepared or loaded colon. METHODS: Two segments of the descended colon were resected and anastomosed in each animal. Group I (12 anastomoses) received preoperative mechanical bowel preparation; the colon was not prepared in Group II (16 anastomoses); in Group III (12 anastomoses), a preliminary distal colonic obstruction was produced, and during the subsequent resection the colon was loaded. Postoperatively, animals were observed clinically, and anastomoses were assessed at autopsy on the ninth day. RESULTS: All animals recovered uneventfully. At autopsy there was no evidence of anastomotic leakage. CONCLUSIONS: In light of recent clinical reports and this experimental study, the ritual of mechanical bowel preparation should be further scrutinized.

Anastomosis, Surgical↗

PubMed1984

Diverticular disease of the colon in Japan. A review of 615 cases.

Of 615 patients with diverticular disease of the colon, 429 had diverticula in the cecum and ascending colon, 98 in the sigmoid and descending colon and 88 in both the right- and left-side colon. The right-sided type was more common in younger people and more predominant in men, whereas the left-sided type was more common in the elderly and showed no difference in numbers between men and women. More than 50 per cent of patients were asymptomatic and 25 per cent complained of disturbed bowel function. The frequency of diverticulitis was not related to location, but to the number of diverticula. Seventy-seven were complicated by acute inflammation (right-sided diverticulitis, 61, and left-sided diverticulitis, 16). Many patients with right-sided diverticulitis improved with medical treatment and the operative procedure of choice was drainage of the inflamed area with supplemental appendectomy.

Adult↗

PubMed1980

Amounts of intestinal microflorae in relation to colon carcinogenesis. An experimental study.

Quantitative analysis of intestinal microflorae in the diverted and feces-containing portions of the colon after performing an ascendo-descendostomy Roux en Y in Wistar-Lewis rats, the colonic portion from the ascending colon to the midportion of the descending colon being diverted from the fecal stream, disclosed a drastic decrease in the total amount of the intestinal microflora as well as most anaerobic microflorae in the diverted portion of the colon where the amount of the colonic content was extremely reduced. This diverted segment was least susceptible of developing macroscopical epithelial neoplasia after exposure to a carcinogen, MNNG, sufficient in amount to evoke multiple large neoplasia in the ordinary colon, although microscopical intramucosal neoplastic foci were induced there. Thus the existence of the intestinal content was essential for the process of promotion in experimental colonic carcinogenesis. The close parallelism between amounts of intestinal content and amounts of intestinal microflorae, especially anaerobic ones, suggested the roles of anaerobic microflorae in colonic carcinogenesis.

Anaerobiosis↗

PubMed2006

Risk of advanced proximal adenoma and cancer according to rectosigmoid findings in the Korean population.

Colorectal cancer is one of the leading causes of cancer death in the United States and Europe. Recently, the incidence of colorectal cancer has been increasing remarkably in Korea. To reduce the high incidence, screening of colorectal cancer in asymptomatic individuals has been advocated. Sigmoidoscopy is simpler, faster, and better tolerable than total colonoscopy, but the scope cannot reach the proximal colon segment and, therefore, may miss proximal colon cancer. In the present study, we intended to investigate the prevalence of proximal adenoma and cancer according to the findings in rectosigmoid colon and to find their risk factors. Data were collected retrospectively from 1541 consecutive patients who underwent total colonoscopy at the Department of Gastroenterology, Hanyang University, between October 2003 and December 2004. Neoplasms were classified as diminutive adenoma (< or =5 mm), small adenoma (6-9 mm), advanced adenoma (> or =10 mm, with villous component or high-grade dysplasia), and cancer. The sites of neoplasms were defined as rectosigmoid (rectum and sigmoid colon) and proximal (from cecum to descending colon) colon. The prevalence of advanced proximal adenoma was associated with severe rectosigmoid findings. On the other hand, the prevalence of proximal colon cancer did not show such a tendency. Among the 131 patients with proximal advanced adenoma, 66% had no neoplasm in the rectosigmoid colon. Moreover, among the 27 patients with proximal cancer, 52% had no neoplasm in the rectosigmoid colon. Multivariate logistic regression analysis revealed that age, gender, and advanced rectosigmoid adenoma were the risk factors of advanced proximal adenoma, but nothing was associated with the risk for proximal colon cancer. Advanced rectosigmoid adenoma may be the predictor of advanced proximal adenoma, especially in old males. However, nothing is related to the risk for proximal colon cancer. Therefore, colonoscopy may be more adequate for colorectal cancer screening than sigmoidoscopy in the Korean population.

Adenoma↗

PubMed1983

Intramural spread of colon carcinoma. A pathologic study.

The results of a pathologic study of 42 colorectal cancers have been presented. Of the 42 lesions, only 2 demonstrated intramural spread. The maximum extent of intramural spread was 2 cm. In one case, intramural spread was in the distal direction. Thirty-six percent of the lesions were in the rectum or rectosigmoid, 19 percent were in the sigmoid colon, 19 percent were in the descending colon, 5 percent were in the transverse colon, and 21 percent were in the right side of the colon. Of the lesions, 14.2 percent were classified Dukes' A, 45.2 percent Dukes' B, and 35.7 percent Dukes' C. Two lesions showed widely disseminated disease. All were adenocarcinomas. Of the five low-lying Dukes' C lesions, three had positive distal lymph nodes. Based on a review of the literature and the findings of this study, a distal margin of resection of 2.5 cm is deemed acceptable. Patients with lesions clinically suspected to be Dukes' C, however, should undergo abdominoperineal resection in an attempt to eradicate distal intramural or lymphatic spread.

Adenocarcinoma↗

PubMed1992

Distal colonic hyperplastic polyps do not predict proximal adenomas in asymptomatic average-risk subjects.

The significance of distal colonic hyperplastic polyps was investigated in 482 asymptomatic average-risk subjects, aged 50-75 years, in whom fecal occult blood test results were negative and who underwent screening colonoscopy. The incidence of adenomas in the colon proximal to the sigmoid-descending colon junction in subjects with hyperplastic polyps distal to that point was 18% and was similar to the incidence of proximal colonic adenomas in subjects with no distal colonic polyps (15%). The incidence of proximal colonic adenomas in subjects with no distal colonic adenomas was 38% and was significantly greater than the incidence found in individuals with no distal colonic polyps or only hyperplastic polyps. Our data do not support distal colonic hyperplastic polyps as markers for proximal colonic adenomas in asymptomatic average-risk subjects.

Adenoma↗

PubMed1991

Effects of selective opioid agonists on feline colonic transit.

The mu agonist morphine and the non-specific opioid antagonist naloxone both may accelerate feline colonic transit; the effects of morphine are dose dependent. Kappa and delta receptor function was studied in the present work. Colonic transit of a radionuclide marker instilled into the cecum was quantitated for 6 hr in a crossover study. The delta agonist [D-Pen2,D-pen5]enkephalin (1 mg/kg, i.m.) prolonged the cecum and ascending colon half-emptying time by 337% (P less than 0.05), and delayed the progression of the geometric center over time. The kappa agonist U-50,488 (1 mg/kg, i.m.) had no apparent effect on the cecum and ascending colon, but delayed filling of the descending colon. Loperamide, an antidiarrheal agent, also delayed colonic transit. Thus, selective opioid agonists have both site and functional differences in their effect on feline colonic transit.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh↗

PubMedDate not supplied

Safety and reliability of tattooing colorectal neoplasms prior to laparoscopic resection.

Accurate tumor localization is critical to performing minimally invasive colorectal resection. This study reviews the safety and reliability of tattooing colorectal neoplasms prior to laparoscopic resection. We retrospectively reviewed 50 consecutive patients with colorectal neoplasms who underwent endoscopic tattooing prior to laparoscopic resection. Data were obtained from medical charts, endoscopy records, and pathology reports. No complications related to endoscopy or tattooing were incurred. Five neoplasms (10%) were in the ascending colon, five (10%) were in the transverse colon, eight (16%) were in the descending colon, 23 (46%) were in the sigmoid colon, and nine (18%) were in the rectum. Tattoos were visualized intraoperatively and accurately localized the neoplasm in 44 patients (88%). Six patients (12%) did not have tattoos visualized laparoscopically and required intraoperative localization. On average, the pathology specimens in this series had a 15 cm proximal margin, a 12 cm distal margin, and 15 lymph nodes. In the context of laparoscopic colorectal resection, preoperative endoscopic tattooing is a safe and reliable method of tumor localization in most cases. Localizing colon and proximal rectal lesions with tattoos may be preferable to other localization techniques including intraoperative endoscopy.

Adenoma↗

PubMed1999

The mucosal phase of Listeria infection.

Listeria monocytogenes is an enteroinvasive bacterial pathogen of man and animals. Listeriae have been shown capable of infecting the host by translocating from the intestinal lumen through Peyer's Patches (PP), however, results of experiments now indicate that these facultative intracellular parasites may also translocate through PP-independent routes. With regards to this, on occasion we observed that listeriae were absent from the PP of mice inoculated intragastrically with L. monocytogenes, but were present in the mesenteric lymph nodes of these same mice. These observations suggested that PP were not necessary for listerial translocation from the intestinal lumen. Two experimental approaches were used to determine whether luminal listeriae could indeed infect the host through PP-independent routes. First, since it is known that: 1) following the intragastric inoculation of L. monocytogenes, listeriae rapidly transit the length of the gastrointestinal tract and reside in the colonic lumen for up to a week, 2) the colon lacks PP, and 3) the descending colon and rectum are drained exclusively by the caudal lymph node (CLN), it was determined whether colonic listeriae could access the CLN. Inoculation of listeriae into the rectum of mice resulted in the infection of the CLN which indicated that PP were not required for listerial translocation. Second, since germfree SCID mice lack PP, it was determined whether listeriae could translocate from the intestinal lumen and infect these immunoincompetent mice. Shortly after the intragastric inoculation of L. monocytogenes into germfree SCID mice, listeriae were found in the mesenteries, livers and spleens. These results also indicate that PP are not required for listerial translocation from the intestinal lumen. One possible route of translocation from the intestinal lumen might occur by listeriae entering enterocytes. Results were obtained showing that listeriae were capable of entering cultured mouse small intestine enterocytes. Internalized listeriae were observed to multiply and spread intracellularly between enterocytes.

Animals↗

PubMed1998

Family history of cancer and risk of colorectal cancer in Italy.

Subjects with a family history of colorectal cancer (CRC) are at increased risk of CRC, but quantification of the risk in different populations, the possible differences in risk according to localization of the cancer and the association of family history of other cancers with CRC risk are still open issues. We have therefore analysed data from a multicentric case-control study conducted in six Italian areas between 1992 and 1996 of 1225 incident cases of colon cancer, 728 cases of rectal cancer and 4154 controls admitted for acute conditions to the same network of hospitals as the cases. Unconditional logistic regression models including terms for gender, age, study centre, years of education and number of siblings were used to estimate the odds ratios (ORs) of CRC according to various aspects of history of CRC and other cancers in first-degree relatives. The OR for family history of CRC was 3.2 (95% confidence interval, CI, 2.5-4.1) for colon cancer and 2.2 (95% CI 1.6-3.1) for rectal cancer. Colon cancer was significantly associated with a family history of stomach (OR 1.4), bone (OR 2.1) and kidney (OR 2.3) cancers, while rectal cancer was significantly associated with a family history of lymphomas (OR 2.8). There was a 30% higher risk of colon and rectal cancer in subjects with a family history of any cancer, excluding intestine. The ORs for family history of CRC were 5.2 for colon and 6.3 for rectum when the proband's age was below 45 years. The ORs were similar when the affected relative was a parent or a sibling and in different strata of age of relative(s). For subjects with two or more first-degree relatives with CRC, the risk was 6.9 for the right colon, 5.8 for the transverse and descending colon, 3.8 for the sigma, 3.2 for the rectosigmoid junction and 1.9 for the rectum. This study confirms that a family history of CRC in first-degree relatives increases the risk of both colon and rectal cancer, the association being stronger at younger ages and for right colon.

Adult↗

PubMed1995

Randomized, double-blinded, placebo-controlled intervention study with supplemental calcium in families with hereditary nonpolyposis colorectal cancer.

BACKGROUND: A high-fat diet has been recognized for some time as a major risk factor for colorectal cancer. It is thought that fat promotes this disease by increasing the levels of fatty and bile acids within the colon. These acids irritate and damage the epithelial cells of the colon. As a result of this cellular destruction, an increase in the rate of cellular proliferation occurs. Oral calcium supplementation has been proposed as a dietary intervention for individuals at high risk of colorectal cancer because of its ability to reduce rectal epithelial cell proliferation through the binding of fatty and bile acids. Placebo-controlled studies, however, have yielded varying results. PURPOSE: We conducted a randomized, double-blinded, placebo-controlled trial to test oral calcium supplementation in patients at high risk of developing hereditary nonpolyposis colorectal cancer. METHODS: Thirty subjects at risk for this cancer, with an increased epithelial cell proliferation along the colon and rectum, were randomly assigned to either a placebo group (n = 15) or a treatment group (n = 15). They received either oral calcium carbonate (CaCO3) supplements (1.5 g) or placebo (cellulose and starch) three times a day during a 12-week period. Colonic biopsy specimens (rectal, sigmoidal, and descending) were obtained prior to and after the intervention trial, during endoscopy, for determination of labeling index (LI) of whole crypts and crypt compartments by 5-bromo-2'-deoxyuridine incorporation and immunohistochemistry. Proportional bile acid compositions in duodenal bile and cytolytic activity of fecal water were also determined. All P values represent two-tailed tests of statistical significance. RESULTS: Statistically significant reductions, comparing before with after intervention, in rectal whole-crypt LI after receiving either calcium supplements (from 10.9% +/- 5.2% [mean +/- SD] to 6.2% +/- 1.5%; P < .02) or placebo (from 11.7% +/- 4.7% to 8.2% +/- 3.1%; P < .05) were observed. In the three bowel segments, no statistically significant differences were observed between the supplemental calcium and placebo groups. A statistically significant reduction in cytolytic activity was determined during calcium supplementation (from 57% +/- 41% to 32% +/- 30%; P < .05), whereas in the placebo group, it did not change (from 42% +/- 41% to 36% +/- 27%; P > .10). CONCLUSIONS: Oral calcium supplementation was shown to cause only a minor nonstatistically significant reduction of epithelial cell proliferation in the rectum, compared with placebo, and to have no effect on the same parameter in the sigmoid and descending colon in first-degree relatives of hereditary nonpolyposis colorectal cancer patients. IMPLICATION: These results cast doubt on the value of calcium supplementation in the prevention of colorectal cancer, especially in individuals already consuming an adequate amount of dietary calcium.

Adolescent↗

PubMed2001

Experience with juvenile polyps in North American children: the need for pancolonoscopy.

We report a recent experience with juvenile polyps (JP) in a large cohort of North American children to determine if a pancolonoscopy (PC) is needed in all children with suspected polyps. We reviewed hospital charts of all patients with JP seen over a 9-yr period (January, 1990-October, 1998). A total of 331 JP were encountered during 195 procedures in 184 patients (64% males, 88% white, mean age 5.93 yr [range 0.42-15.5 yr], median age 4.84 yr). Painless rectal bleeding was the commonest symptom. PC was performed in 42% (82/195) of procedures, and 177 JP were encountered: 54% (97/177) were in the rectosigmoid colon, 14% (24/177) were in the descending colon, and 32% (56/177) were proximal to the splenic flexure (i.e., proximal polyps). Overall, proximal polyps were seen in 37% (31/82) of PC. Only proximal polyps were noted in 12% (10/82) of PC. Five patients were re-endoscoped after an initial limited examination because of continuing symptoms from proximal polyps. All but one of the polyps had typical features of a JP on histological examination. Though most JP are located in the left colon, a PC should be the initial procedure because: 1) 37% of PC revealed proximal polyps, 2) 32% of polyps were located proximal to splenic flexure, 3) persistence of symptoms from missed proximal polyp(s) necessitates a repeat study with attendant risks, and 4) there is a possibility of malignant transformation in an unidentified JP.

Adenomatous Polyposis Coli↗

PubMed1989

Pseudomembranous colitis with rectosigmoid sparing on barium studies.

The classic description of pseudomembranous colitis on barium enema studies is that of pancolitis with thickened haustral folds, a shaggy luminal contour, and/or mucosal plaques. However, the authors describe six patients with proved pseudomembranous colitis in whom barium studies (four double-contrast barium enema studies, one single-contrast barium enema study, and one peroral pneumocolon study) demonstrated rectosigmoid sparing with proximal colitis extending from the cecum to the sigmoid colon (three cases) or to the descending colon (three cases). In all six cases, endoscopy revealed a normal rectum or mild, nonspecific proctosigmoiditis without evidence of pseudomembranes in the rectosigmoid colon. Four patients had an atypical clinical presentation with bloody diarrhea (three cases) or minimal mucous diarrhea (one case). Thus, the diagnosis of pseudomembranous colitis may initially be suggested on barium studies in patients who have relative sparing of the rectosigmoid colon with characteristic findings more proximally in the colon.

Barium Sulfate↗

PubMed1999

Acute colorectal obstruction: treatment with self-expandable metallic stents before scheduled surgery--results of a multicenter study.

PURPOSE: To evaluate the efficacy of treatment with self-expandable metallic stents for acute colonic obstruction before elective surgical resection. MATERIALS AND METHODS: In 71 patients with malignant obstruction seen from October 1993 through December 1996, lesions were located in the transverse colon in one patient, in the descending colon in 22 patients, and in the rectosigmoid region in 48. A total of 72 self-expandable metallic stents were implanted within 24 hours of diagnosis. RESULTS: Technical success was obtained in 64 patients (90%). In two cases (3%), it was not possible to advance across the obstructing mass. In five cases (7%), the prostheses were poorly positioned at the site of obstruction, requiring placement of a new stent in three cases. Clinical improvement and resolution of the obstruction were confirmed in 66 patients (93%) within 96 hours. Minor complications developed in nine cases (13%). One patient (1%) underwent surgery to resolve a colonic perforation caused by wires at the ends of the stent. The mean time between stent placement and surgery was 8.6 days (range, 6-16 days). CONCLUSION: Implantation of colorectal stents is a safe treatment of acute malignant colonic obstruction before resection.

Acute Disease↗

PubMed2001

Viscoelastic properties of the human colon.

Our objectives were to characterize colonic viscoelastic properties of the human descending colon by assessing pressure-volume (P-V) relationships during barostatic balloon distension. In 16 healthy subjects, a balloon was inflated to 44 mmHg and then deflated to 0 mmHg in 4-mmHg steps at 10, 30, and 60 ml/min, allowing volume fluctuations to stabilize at each pressure increment. Thereafter, these "quasi-static" P-V curves were compared with "dynamic" distensions to 300 ml, at 1 and 10 ml/s, before and after intravenous atropine in another five subjects. During quasi-static curves, balloon volume stabilized at each pressure increment. Quasi-static P-V curves were reproducible within individuals and approximated to a power exponential function and revealed hysteresis, indicative of viscoelasticity. Body mass index influenced quasi-static P-V curves during inflation but not during deflation. The colon was less compliant during dynamic distensions at 10 ml/s than during quasi-static distensions. Atropine increased quasi-static compliance and attenuated differences between quasi-static and rapid distensions. We conclude that colonic viscoelastic properties can be assessed by quasi-static P-V curves. Rapid colonic distension activated neural reflexes, thereby reducing colonic compliance compared with quasi-static distensions.

Adult↗