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PubMed1993

Quality of mucosal coating in double-contrast barium enema studies: comparison of two barium preparations.

To determine which of two types of barium preparation, a dry powder (AC-14, E-Z-EM, Montreal) or a premixed suspension (Liquid Polibar Plus, E-Z-EM), gives better mucosal coating for double-contrast enema studies, the authors compared the results of two series of 80 examinations each, one for each of the preparations. The films were retrospectively reviewed by two independent observers, who did not know which preparation had been used for a given examination. Mucosal coating was graded on a five-point scale and the amount of barium on a three-point scale. Each area of the colon--the cecum, the ascending, the transverse and the descending colon and the rectosigmoid--was rated separately. The premixed barium suspension yielded significantly better mucosal coating than the dry powder in all areas of the colon (p < 0.01). There was no significant difference between the two preparations in the amount of barium deposited in any region of the colon (p > 0.05) or in the proportion of unsatisfactory examinations (p > 0.05). The authors conclude that the premixed suspension yielded better-quality mucosal coating than a suspension made from the dry powder and resulted in a similar high proportion of technically satisfactory studies.

Barium Sulfate↗
PubMed1982

Noise analysis reveals K+ channel conductance fluctuations in the apical membrane of rabbit colon.

In this paper we describe current fluctuations in the mammalian epithelium, rabbit descending colon. Pieces of isolated colon epithelium bathed in Na+ or K+ Ringer's solutions were studied under short-circuit conditions with the current noise spectra recorded over the range of 1-200 Hz. When the epithelium was bathed on both sides with Na+ Ringer's solution (the mucosal solution contained 50 microM amiloride), no Lorentzian components were found in the power spectrum. After imposition of a potassium gradient across the epithelium by replacement of the mucosal solution by K+ Ringer's (containing 50 microM amiloride), a Lorentzian component appeared with an average corner frequency, fc = 15.6 +/- 0.91 Hz and a mean plateau value So = (7.04 +/- 2.94) x 10(-20) A2 sec/cm2. The Lorentzian component was enhanced by voltage clamping the colon in a direction favorable for K+ entry across the apical membrane. Elimination of the K+ gradient by bathing the colon on both sides with K+ Ringer's solutions abolished the noise signal. The Lorentzian component was also depressed by mucosal addition of Cs+ or tetraethylammonium (TEA) and by serosal addition of Ba2+. The one-sided action of these K+ channel blockers suggests a cellular location for the fluctuating channels. Addition of nystatin to the mucosal solution abolished the Lorentzian component. Serosal nystatin did not affect the Lorentzian noise. This finding indicates an apical membrane location for the fluctuating channels. The data were similar in some respects to K+ channel fluctuations recorded from the apical membranes of amphibian epithelia such as the frog skin and toad gallbladder. The results are relevant to recent reports concerning transcellular potassium secretion in the colon and indicate that the colon possesses spontaneously fluctuating potassium channels in its apical membranes in parallel to the Na+ transport pathway.

Animals↗
PubMed1984

Colonic cancer in pregnancy.

We have described a case of adenocarcinoma of the descending colon in a 29-year-old pregnant woman, and have reviewed the problems of diagnosis and management and the role of reproductive and hormonal factors in relation to colonic cancer. Ours is the 20th reported case of colonic cancer during pregnancy.

Adenocarcinoma, Mucinous↗
PubMed1980

[Inhibition of sodium transport in the colon by the diuretic amiloride (author's transl)].

In isolated epithelia of rabbit descending colon the short-circuit current (Isc) is solely attributable to net transepithelial Na-transport, which in turn is identical with the unidirectional Na-influx across the luminal cell membranes. Amiloride blocks Isc by inhibiting luminal Na-influx into the cells. The type of inhibition exerted by amiloride in this tissue has to be termed mixed-type, since both the affinity of Na to its transport system and the maximal transport capacity are reduced. Na, on the other hand, is a competitive antagonist of the amiloride effect with a Ki of 136 mM; therefore KA, the amiloride-concentration at which the amiloride-effect is half-maximal, is increased from 0.14 microM at 5 mM Na in the incubation medium to 0.29 microM at 140 mM Na. It is conceivable that an "amiloride-like" action of Na may be responsible for the saturability of luminal Na-influx with increasing Na-concentrations.

Amiloride↗
PubMed1977

Colonic obstruction by giant pseudopolyposis.

A case of obstructing giant pseudopolyposis of the descending colon is described. A review of the clinical course of this patient and a discussion of giant pseudopolyposis is presented. The pathological features of this giant pseudopolyp is described. Carcinoma of the colon has not been found to arise in inflammatory polyps and it is felt that surgery in nonobstructed patients with giant pseudopolyposis may not be necessary.

Adult↗
PubMed1981

Effect of estrogen on cell proliferation in colonic mucosa of the mouse.

The effect of estrogen on cell proliferation in the descending colon of the mouse as an example of a non-target organ was investigated. Ovariectomized mice were given single or multiple injections of 10 ng/g body weight of 17 beta-estradiol and were killed 1 h after 3H-thymidine injection. Estrogen treatments decreased incorporation of 3H-thymidine into the DNA of colonic mucosa most markedly at 4 h after the single or the last of multiple injections. The inhibitory effect of estrogen on 3H-thymidine incorporation was greater and lasted longer after a single injection than after multiple ones. A similar inhibitory effect was observed in the colonic mucosa of male mice as well as in the mucosa of mice in which colonic epithelial cell proliferation was enhanced by refeeding after 48 h of fasting. However, the colonic mucosa of mice treated with estrogen implants for up to 4 days was not affected. Estrogen treatments caused no significant change in the DNA, RNA and protein contents of the colonic mucosa. The efficacy of estrogen treatments was verified by an increase in both the wet and dry weights of the uterine horns of ovariectomized mice.

Animals↗
PubMed1977

Vascular occlusion and stricture of the sigmoid colon secondary to trauma from a pneumatic hammer.

A patient with stricture of the descending colon secondary to use of a pneumatic hammer is presented. Barium enema and angiographic studies suggested that the etiology was a traumatic vascular injury. Barium granulomata, found in the resected specimen, were presumably due to barium having entered the devitalized tissues during an air contrast study performed during an acute ischemic colitis. The mechanisms of traumatic strictures of the colon are discussed.

Accidents, Occupational↗
PubMed1988

Rhein stimulates active chloride secretion in the short-circuited rat colonic mucosa.

In a short-circuited mucosa-submucosa preparation of the rat descending colon with preserved Meissner's plexus mounted as an everted sac rhein transiently increased the potential difference and short-circuit current (Isc) when administered serosally and mucosally, but serosal application was more effective. Maximal effects were obtained at rhein concentrations of 1.6 X 10(-4) and 3 X 10(-4) mol/l. Net chloride absorption was decreased. Indomethacin (5 X 10(-6) mol/l) did not inhibit the increase of Isc, but omission of calcium from the serosal side as well as tetrodoxin (2 X 10(-7) mol/l) decreased it by 50 and 60%. Mechanical removal of Meissner's plexus partly blocked the effect of rhein, too. It is concluded that rhein stimulates colonic secretion by a direct action on the epithelial cells together with an indirect action via neurohumoral mechanisms.

Animals↗
PubMed1996

[A case of solitary splenic metastasis from colon cancer].

A 58-year-old male who had a left hemicolectomy for descending colon cancer on July 1, 1993 was admitted to our hospital. A CT scan revealed a homogeneous low-density mass in the inferior portion of the spleen. Under the diagnosis of solitary splenic metastasis, a splenectomy was performed on August 10, 1995. Histologically, splenic tumor revealed moderately differentiated adenocarcinoma consistent with the primary tumor. Flow cytometric analysis revealed DNA diploidy in the primary tumor, and DNA aneuploidy (DNA index = 1.76) in the metastatic tumor. Using fluorescence in situ hybridization with p17 H8, numerical aerrations of chromosome 17 were observed in the primary tumor.

Adenocarcinoma↗
PubMed1989

Colonic complications of severe acute pancreatitis.

Colonic complications are rare in acute pancreatitis. Over the last 9 years at St. Mary's Hospital, London, UK, we have managed severe acute pancreatitis by intensive supportive therapy followed by sub-total pancreatic resection and/or debridement in those who fail to improve. Of the 22 patients who have undergone this form of surgery, nine were found to have colonic involvement in the form of either necrosis or perforation. In addition, one patient presenting at West Middlesex University Hospital, Isleworth, UK, had severe acute pancreatitis and almost total colonic necrosis as an unexpected finding at emergency laparotomy. These ten patients comprised seven men and three women of median age 59 years and with a median of four Ranson criteria. In seven patients, colonic involvement was discovered at the time of pancreatic surgery or laparotomy for pancreatitis and in the remainder it presented between 1 and 3 weeks later as either a faecal fistula (n = 2) or persistent abdominal sepsis (n = 1). The ascending colon was involved in one patient, the splenic flexure and descending colon in one, the transverse colon in three, the splenic flexure alone in four, and one patient had almost total colonic involvement. All patients underwent resection of the involved colon and exteriorization with either a proximal colostomy (n = 7) or ileostomy (n = 3) and a distal mucous fistula. Pathological examination of the resected colons revealed a spectrum of changes from pericolitis through to ischaemic necrosis suggesting at least two possible mechanisms. Six patients died from overwhelming sepsis between 1 day and 4 weeks (median 11 days) after colonic resection. Severe acute pancreatitis must be recognized as a cause of colonic ischaemia and necrosis; this complication is associated with a very poor prognosis despite surgical intervention.

Acute Disease↗
PubMed2003

Frequency of loss of hMLH1 expression in colorectal carcinoma increases with advancing age.

BACKGROUND: The correlation between age at diagnosis and loss of expression of hMLH1 protein in patients with colorectal carcinoma (CRC) has not been evaluated systematically. METHODS: Immunohistochemistry was performed for hMLH1 protein in tumor samples from 867 patients with CRC. The authors defined tumors arising in the cecum, ascending colon, and transverse colon as right-sided and tumors arising in the descending colon, sigmoid colon, and rectum as left-sided. Patients' gender, tumor location (side), and hMLH1 expression were analyzed by age groups. RESULTS: The percentage of tumors with hMLH1 expression loss increased significantly with advancing age (P < 0.0001): There were no tumors in patients age < 40 years that manifested loss of hMLH1 expression, compared with 29% of tumors that manifested loss of hMLH1 expression in patients age > 90 years. Loss of hMLH1 expression occurred more often in patients with right-sided tumors (32.7% vs. 5.2% of patients with left-sided tumors; P < 0.0001) and in tumors from female patients (24.3% vs. 11.5% of tumors from male patients; P < 0.0001). There was no evidence of interaction between gender and tumor location. CONCLUSIONS: Loss of hMLH1 expression in patients with CRC was associated strongly with increasing age. hMLH1 expression loss was more pronounced in tumors from female patients and in tumors that originated on the right side of the colon. Loss of hMLH1 expression in right-sided tumors occurred in nearly 50% of patients age > 90 years. This age-related trend also was observed for males and in tumors that originated in the left colon.

Adaptor Proteins, Signal Transducing↗
PubMed2006

Early effects of fibrin sealant on colonic anastomosis in rats: an experimental and case-control study.

BACKGROUND: Leakage from colonic anastomoses leads to mortality and morbidity. Fibrin adhesives can be used to increase the strength of the anastomosis. In this study, we evaluated the early effects of fibrin sealant and hyaluronic acid-carboxymethylcellulose on colonic anastomosis in rats. METHODS: Anastomoses were made in the descending colon of 38 female Wistar-Albino rats, in three groups: control group (n = 12), group 1 treated with hyaluronic acid-carboxymethylcellulose (n = 16), and group 2 treated with fibrin sealant (n = 10). After 72 hours, adhesion scores, bursting pressure, rupture strength and histopathologic healing scores were evaluated. RESULTS: Due to postoperative mortality, we evaluated 10, 10 and 9 rats in the control group and in groups 1 and 2, respectively. Of these, we excluded 4, 5 and 4 rats that had macroperforations at autopsy. In the remaining rats, bursting pressure (123.2 +/- 14.8 mmHg) and rupture strength (400 +/- 16 mg) in the fibrin sealant group were significantly greater than in the two other groups ( CONTROL: 68.0 +/- 10.6 p = 0.006 and 325 +/- 52 p = 0.009; Group 1: 74.0 +/- 9.8 p = 0.03, 330 +/- 27 p = 0.016). However, we did not observe any significant difference between adhesion scores (2.5 +/- 0.6, 2.0 +/- 0.7, 2.0 +/- 0.7, p = 0.343). CONCLUSIONS: In this experimental study, fibrin sealant increased bursting pressure and rupture strength of colonic anastomoses while hyaluronic acid-carboxymethylcellulose had no effects in rats, but both of them showed no effect on adhesion scores. In order to use fibrin sealant to decrease the rate of early leakages from colonic anastomoses, further studies have to be performed.

Anastomosis, Surgical↗
PubMed1998

Review article: colonic sensorimotor physiology in health, and its alteration in constipation and diarrhoeal disorders.

AIM: To review the physiology of colonic motility and sensation in healthy humans and the pathophysiological changes associated with constipation and diarrhoea. SOURCE: Medline Search from 1965 using the index terms: human, colonic motility, sensation, pharmacology, neurohormonal control, gastrointestinal transit, constipation, diarrhoea and combinations of these. RESULTS: In health, the ascending and transverse regions of colon function as reservoirs to accommodate ileal chyme and the descending colon acts as a conduit; the neuromuscular functions and transmitters control colonic motility and sensation and play pivotal roles in disorders associated with constipation and/or diarrhoea. Disorders of proximal colonic transit contribute to symptoms in idiopathic constipation, diarrhoea-predominant irritable bowel syndrome and carcinoid diarrhoea. Colonic function in patients presenting with constipation is best assessed clinically by colonic transit time using radiopaque markers ingested orally. Measurements of colonic contractility are less useful clinically but they can help identify motor abnormalities including colonic inertia; in some patients with irritable bowel syndrome, abdominal pain, urgency and diarrhoea are temporally associated with high amplitude contractions, which originate in the proximal colon and traverse the distal conduit at very high propagation velocities. Visceral hypersensitivity contributes to the urgency and tenesmus in irritable bowel syndrome and inflammatory bowel disease. Colonic motility and sensation can be reduced by anticholinergic agents, somatostatin analogues and 5HT3 antagonists. CONCLUSION: Physiological and pharmacological studies of the human colon have provided new insights into the pathophysiology of colonic disorders, and offer possibilities of novel therapeutic approaches for constipation or diarrhoea associated with colonic motor or sensory dysfunction.

Colon↗
PubMed1994

[Enterocolic fistula due to foreign body perforation].

A 26-year-old man reported diarrhoea, abdominal pain and weight loss (16 kg in 3 weeks). Ultrasonography and computed tomography showed a 5 x 5 cm abnormal rosette-shaped mass with surrounding infiltration in the area of the left colic flexure. Laboratory tests indicated a florid inflammation. Coloscopy and double-contrast radiology of the colon revealed a fistula at the junction between sigmoid and descending colon. At laparotomy a large tumorous mass was found (18 x 15 x 10 cm), which was removed completely by partial resection of small intestine and colon. Histological examination revealed occlusion of an intestinal loop by a plastic foreign body (probably the cap of a household cleaner bottle). The patient would not provide any explanation of the circumstances leading to its ingestion.

Adult↗
PubMed1990

Mechanical aspects of rabbit fecal dehydration.

The hydrostatic pressure required to reduce the water content of rabbit feces in an odometer from greater than 80 to less than 65% was approximately 5 atm. This pressure was unaffected by raising the temperature from 20 to 37 degrees C. It became progressively more difficult to dehydrate feces as consolidation occurred, as is evident from the significant (P less than 0.001) reduction in the fecal consolidation coefficient (Co) from 1.76 +/- 0.25 X 10(-6) (n = 4) to 1.35 +/- 0.093 X 10(-7) m2/s (n = 4) and the fecal fluid permeability coefficient (k) from 4.10 +/- 0.51 X 10(-8) (n = 4) to 1.42 +/- 0.12 X 10(-10) m/s (n = 4), concomitant with the reduction in fecal water content. The results suggest that rabbit hard feces are unlikely to be produced, under physiological conditions, by mechanical pressure exerted by the wall of the colon or by a prolonged retention time of hard feces by the distal colon. The hypertonic absorbate (1,000 mosmol/kg) produced by rabbit descending colon is of sufficient magnitude to overcome the fecal resistance to dehydration.

Animals↗
PubMed1996

Sonographically guided hydrostatic reduction of childhood intussusception using Hartmann's solution.

OBJECTIVE: Currently, the standard methods for therapeutic reduction of intussusception in children involve considerable ionizing radiation. This study tested the effectiveness of sonographically guided hydrostatic reduction of intussusception using Hartmann's solution, a fluid with near-physiologic composition. SUBJECTS AND METHODS: Between March 1, 1994, and January 31, 1996, all children clinically suspected of having intussusception were evaluated by sonography. Those with positive findings on sonography were entered into the study and underwent confirmatory sonographically guided meglumine diatrizoate enema. During continuous sonographic monitoring, we used Hartmann's solution for attempted reduction of intussusception. Criteria for successful reduction were disappearance of the intussusceptum and passage of fluid through the ileocecal valve. Another sonographically guided meglumine diatrizoate enema was used to confirm successful reduction. RESULTS: We detected 25 consecutive intussusceptions in 22 patients. The patients were 12 girls and 10 boys, with a mean age of 14 months (range, 1-72 months). Sonograms revealed in all patients doughnut or pseudokidney signs or both. The sites of intussusception were the transverse colon (17 of 25), hepatic flexure (4 of 25), ascending colon (2 of 25), splenic flexure (1 of 25), and descending colon (1 of 25). Other findings were dilated fluid-filled small bowel (11 of 25) and free intraperitoneal fluid (9 of 25). The success rate of our sonographically guided attempts at hydrostatic reduction was 76% (19 of 25). Success was proven by meglumine diatrizoate enema in all 19 patients. The mean time of the reduction procedure was 18 min (range, 2-45 min). No complications occurred. All six patients in whom hydrostatic reduction was unsuccessful underwent surgery. Five of these patients had ileoileocolic intussusceptions. On sonography, when surrounded by fluid, ileoileocolic intussusceptions had a typically complex, fronded appearance. The remaining patient in whom hydrostatic reduction was unsuccessful had ileocolic intussusception. Of six ileoileocolic intussusceptions, one was hydrostatically reduced and a second was converted into an ileoileal intussusception before requiring surgery. The other four intussusceptions were surgically treated. CONCLUSION: Our data suggest that sonographically guided hydrostatic reduction with Hartmann's solution can be used to treat ileocolic intussusception and to diagnose ileoileocolic intussusception.

Catheterization↗
PubMed2002

Diagnostic and pathogenetic implications of colorectal carcinomas with multidirectional differentiation: a report of 4 cases.

Multidirectional differentiation in colorectal carcinomas is a rare phenomenon. Four cases are reported herein, and their clinical and pathologic characteristics are discussed. Two men and 2 women between the ages of 56 and 76 years who presented with abdominal symptoms are included in this report. Two tumors were located in the right colon, one in the splenic flexure, and one in the descending colon. Distant metastases were evident at presentation in 3 of 4 cases. Histologically, two tumors exhibited neuroendocrine and glandular differentiation; the third tumor was an adenocarcinoma with a sarcomatous component and the fourth tumor showed 3 lines of differentiation (glandular, squamous, and sarcomatoid). In all tumors evaluated, areas of adenocarcinomas were positive for low-molecular weight cytokeratin (CAM 5.2) and mucicarmine, but negative for high-molecular weight cytokeratin (AE3). The squamous cell component was AE3 positive and CAM 5.2 negative. The neuroendocrine component was highlighted by neuroendocrine markers and the sarcomatoid component revealed smooth muscle differentiation. All tumors (except one mucinous tumor) were negative for cytokeratin-20 staining. One patient was on supportive care for terminal metastatic carcinoma, and 2 patients were being treated with adjuvant chemotherapy at the time of this report. Colon carcinoma with multidirectional differentiation is a rare event and may originate from stem cells within the gastrointestinal mucosa, and/or represent the convergence of multiple tumors arising at the same site. This type of tumor should be considered in the differential diagnosis of a bowel biopsy with multiple histopathologic variants.

Adenocarcinoma↗
PubMed1999

A new rectal model for dosimetry applications.

UNLABELLED: A revised geometric representative model of the lower part of the colon, including the rectum, the urinary bladder and prostate, is proposed for use in the calculation of absorbed dose from injected radiopharmaceuticals. The lower segment of the sigmoid colon as described in the 1987 Oak Ridge National Laboratory mathematical phantoms does not accurately represent the combined urinary bladder/rectal/prostate geometry. In the revised model in this study, the lower part of the abdomen includes an explicitly defined rectum. The shape of sigmoid colon is more anatomically structured, and the diameters of the descending colon are modified to better approximate their true anatomic dimensions. To avoid organ overlap and for more accurate representation of the urinary bladder and the prostate gland (in the male), these organs are shifted from their originally defined positions. The insertion of the rectum and the shifting of the urinary bladder will not overlap with or displace the female phantom's ovaries or the uterus. In the adult male phantom, the prostatic urethra and seminal duct are also included explicitly in the model. The relevant structures are defined for the newborn and 1-, 5-, 10- and 15-y-old (adult female) and adult male phantoms. METHODS: Values of the specific absorbed fractions and radionuclide S values were calculated with the SIMDOS dosimetry package. Results for 99mTc and other radionuclides are compared with previously reported values. RESULTS: The new model was used to calculate S values that may be crucial to calculations of the effective dose equivalent. For 131I, the S (prostate<--urinary bladder contents) and S (lower large intestine [LLI] wall<--urinary bladder contents) are 6.7 x 10(-6) and 3.41 x 10(-6) mGy/MBq x s, respectively. Corresponding values given by the MIRDOSE3 computer program are 6.23 x 10(-6) and 1.53 x 10(-6) mGy/MBq x s, respectively. The value of S (rectum wall<--urinary bladder contents) is 4.84 x 10(-5) mGy/MBq x s. For 99mTc, we report S (testes<--prostate) and S (LLI wall<--prostate) of 9.41 x 10(-7) and 1.53 x 10(-7) mGy/MBq x s versus 1.33 x 10(-6) and 7.57 x 10(-6) mGy/MBq x s given by MIRDOSE3, respectively. The value of S (rectum wall<--prostate) for 99mTc is given as 4.05 x 10(-6) mGy/MBq x s in the present model. CONCLUSION: The new revised rectal model describes an anatomically realistic lower abdomen region, thus giving improved estimates of absorbed dose. Due to shifting the prostate gland, a 30%-45% reduction in the testes dose and the insertion of the rectum leads to 48%-55% increase in the LLI wall dose when the prostate is the source organ.

Adult↗