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PubMed1995

Laparoscopic anatomy of the equine abdomen.

Laparoscopy was performed on 6 horses (2 mares, 2 geldings, 2 stallions) to determine the normal laparoscopic anatomy of the equine abdomen. After withholding feed for 36 hours, horses were examined from the left and right paralumbar fossae, and the visceral anatomic structures were recorded by videotape and photography. One mare developed emphysema located subcutaneously at the primary laparoscopic portal; otherwise, there were no complications. The anatomic structures of diagnostic importance that were observed in the left half of the abdomen were the hepatic duct; left lateral and quadrate lobes of the liver; stomach; spleen; left kidney with the associated nephrosplenic ligament; segments of jejunum, descending colon, and ascending colon; left side of the male and female reproductive tracts; urinary bladder; vaginal ring; and mesorchium. Important structures observed in the right side of the abdomen were portions of the common hepatic duct; left lateral, quadrate, and right lobes of the liver; caudate process of the liver; stomach; duodenum; right dorsal colon, epiploic foramen; omental bursa; right kidney; base of the cecum; segments of jejunum, descending colon, and ascending colon; urinary bladder; right half of the male and female reproductive tracts; and rectum.

Abdomen↗
PubMed1992

Right and left colonic transit after eating assessed by a dual isotopic technique in healthy humans.

Propulsion of colonic contents after eating in the whole colon was studied in 15 volunteers by scintigraphy with injection of 111In-diethylenetriamine-pentaacetic acid and 99mTc-sulfur colloid into the colon through a nasogastric tube. The radionuclide was injected into the cecoascending colon (n = 7), the hepatic flexure (n = 6), the splenic flexure (n = 9), and the descending colon (n = 4). Changes of activity in the regions distal from and proximal to the injection points were determined before and after a 1000-kcal meal. Isotopic movements were also analyzed when a simultaneous injection of the two markers in the right and left parts of the colon was achieved (n = 11). During fasting, no significant change of activity was seen. After eating, radioactivity injected into the cecoascending and the hepatic flexure was transferred distally (P less than 0.01 and P = 0.07); radioactivity injected into the splenic flexure was transferred both distally (P = 0.07) and proximally (P less than 0.02); and no significant change of activity was seen proximally from or distally to the descending colon. Both antegrade and retrograde isotopic movements increased after eating (P less than 0.01), but the number of antegrade movements was significantly greater (P less than 0.05). This study confirms the colonic propulsive effect of eating and shows that this response is different in the right and left parts of the colon.

Adult↗
PubMed1984

Effects of dopamine and bromocriptine on colonic motility in dog.

The effects of intravenous infusions of dopamine (0.1 to 1 mg kg-1h-1) and bromocriptine (10 to 40 micrograms kg-1h-1) on colonic motility were investigated in fasted dogs fitted with permanent strain gauges on the ascending, transverse and descending colon. Infused at rates of 0.5 and 1 mg kg-1h-1 during 1 h, dopamine immediately stimulated the motility of the descending colon; after a delay of 40 to 60 min this effect was balanced by an inhibition of the motility of the ascending and transverse colon. Bromocriptine infused intravenously at doses of 10 to 40 micrograms kg-1h-1 stimulated the motility of the whole colon but these effects were limited to the duration of the infusion (60 min). Both propranolol (0.5 mg kg-1) and tolazoline (2 mg kg-1) failed to block the effects of dopamine and bromocriptine whereas phentolamine (0.1 mg kg-1) and prazosin (0.2 mg kg-1) partially reduced the inhibitory effects of dopamine on the proximal colon. Haloperidol at doses higher than 0.2 mg kg-1 and domperidone blocked the bromocriptine-induced stimulation of colonic motility which was unaffected by previous treatment with alpha- and beta-adrenoceptor blocking agents. These results suggest that in the dog, dopamine and bromocriptine stimulate colonic motility through specific dopamine receptors. However, they suggest that the inhibitory effects of dopamine on the proximal colon which are blocked by dopamine antagonists are also partially due to an effect on alpha 1-adrenoceptors.

Adrenergic alpha-Antagonists↗
PubMed1989

Distribution of 2-naphthol sulphotransferase and its endogenous substrate adenosine 3'-phosphate 5'-phosphosulphate in human tissues.

The activity of sulphotransferase towards 2-naphthol and the concentration of its endogenous substrate, adenosine 3'-phosphate 5'-phosphosulphate (PAPS), have been measured in five specimens of human liver, lung, and kidney, and the mucosa from the ileum and the ascending, descending and sigmoid colon. The activity of 2-naphthol sulphotransferase (mean nmol.min-1.mg-1 protein) was 1.82 (liver); 0.034 (kidney); 0.19 (lung); 0.64 (ileum); 0.47 (ascending colon); 0.50 (descending colon); 0.40 (sigmoid colon). The concentration of PAPS (mean nmol.g-1 wet tissue) was 22.6 (liver); 4.8 (kidney); 4.3 (lung); 12.8 (ileum); 8.1 (ascending colon); 7.5 (descending colon); 6.2 (sigmoid colon). The concentration of PAPS and the activity of 2-naphthol sulphotransferase were higher in the liver than in the extrahepatic tissues. There was significant difference between ileum and ascending colon, both the activity of sulphotransferase and the concentration of PAPS being higher in the former. 2-Naphthol sulphotransferase activity and the concentration of PAPS have consistent distribution patterns. Differences between the tissues studied were more marked for sulphotransferase than for its endogenous substrate.

Adenine Nucleotides↗
PubMed1979

Method of preparing isolated colonic epithelial cells (colonocytes) for metabolic studies.

Suspensions of isolated colonic epithelial cells (colonocytes) have been obtained from rats by incubating everted lengths of colon with EDTA at 37 degrees C in Krebs-Henseleit saline from which calcium was omitted and containing 0.25% (w/v) bovine serum albumin. Measurements of oxygen consumption and lactate production by cell suspensions indicate that they are metabolically active for at least one hour. The method has been modified for the preparation of isolated epithelial cells from the human colon by including an enzyme digestion step and by increasing the concentration of EDTA to 10 mM. Human colonocytes have been obtained either from normal mucosa (ascending and descending colon) or from the mucosa in ulcerative colitis (descending colon). Oxygen consumption of human cell suspensions is lower than in the rat but in colonocytes from both species the rate is increased by glucose and by n-butyrate, a normal constituent of the colonic lumen. The method yields metabolically active cell suspensions from diseased colonic mucosa and promises to be of value for biochemical studies of ulcerative colitis.

Animals↗
PubMed2002

Small colonic J-pouch improves colonic retention of liquids--randomized, controlled trial with scintigraphy.

PURPOSE: A small 6-cm colonic J-pouch improves stool frequency and continence, without stool evacuation problems. However, the reservoir function is not improved on physiologic studies. Hence, a scintigraphy technique was devised to study the transit of solid and liquid colonic contents in these patients. METHODS: Patients were randomly assigned to straight or colonic J-pouch anal anastomoses after ultralow anterior resection. At 1 year after surgery, they were studied by bowel questionnaire, anorectal manometry, and technetium TC 99m tin-colloid liquid test meal/I-131 microcapsule scintigraphy. In the latter, technetium TC 99m tin-colloid was ingested orally to image the colonic liquids. I-131 microcapsules taken simultaneously imaged the solid stools. After ingestion of the radioisotopes, imaging was performed at intervals of 7 to 8, 24, and 56 hours later. Two independent observers noted the presence of technetium TC 99m tin-colloid liquid and I-131 microcapsules in various areas of interest drawn over the colon. RESULTS: There were six patients (5 males, mean age, 61.5 (SE mean, 1.9) years) in the straight, and six patients (5 males, mean age, 63.2 (4.5) years) in the colonic J-pouch group. Stool frequency was more in the straight group (4.8 (0.4) vs. 3 (0.2) stools/day; P <.001). Continence, evacuation problems, and anorectal physiologic findings were not different. Technetium TC 99m tin-colloid (imaging liquids) transited significantly faster than I-131 microcapsules (imaging solids), at various areas of interest in the colon. In the colonic J-pouch patients, technetium TC 99m tin-colloid liquid was retained significantly longer in the descending colon at 24 hours (P <.05). Stool frequency was higher when technetium TC 99m tin-colloid was not retained in the descending colon at 56 hours (3.3 (0.5) vs. 4.3 (0.4) stools/day) but this did not reach statistical significance. There were no significant differences in the distribution of the ingested I-131 microcapsules between colonic J-pouch and straight groups. CONCLUSIONS: Reduced stool frequency after colonic J-pouch may be related to factors causing better retention of liquid stools in the distal colon. No difference in solid stool transit could possibly account for minimal evacuation problems in small pouches.

Aged↗
PubMed1995

Hyperglycemia inhibits mechanoreceptor-mediated gastrocolonic responses and colonic peristaltic reflexes in healthy humans.

BACKGROUND/AIMS: The effects of hyperglycemia on colonic motor function are unknown. Therefore, colonic neuromuscular function was tested in normal volunteers as a model for constipation in diabetes. METHODS: Extended (gastrocolonic response) and local (peristaltic reflex) neural responses and colonic muscle contractility were tested under control, hyperglycemic clamp, and euglycemic, hyperinsulinemic clamp conditions with placement of barostat-regulated balloons in the descending colon to measure changes in tone as differences in balloon volume. RESULTS: Hyperglycemic clamping to 274 +/- 3 mg/dL blunted increases in colon tone evoked by gastric distention (gastrocolonic response) (100-300 mL) but did not affect gastric tone. Three descending colonic balloons in series assessed the peristaltic reflex. Inflation of the middle stimulus balloon increased proximal tone, an increase that was blunted by hyperglycemia, but produced distal relaxation followed by increases in tone that were unaffected by hyperglycemia. Euglycemic, hyperinsulinemic clamping had no effect on the gastrocolonic response or peristaltic reflex. Tonic increases evoked by bethanechol (5 mg administered subcutaneously) were unaffected by hyperglycemic clamping. CONCLUSIONS: Hyperglycemia blunts mechanoreceptor-mediated gastrocolonic responses and ascending contractions but not descending components of the peristaltic reflex in humans, effects not caused by hyperinsulinemia or direct muscle actions. These inhibitory effects on long and short neural reflexes that modulate colonic motility may contribute to constipation in diabetes.

Adult↗
PubMed2000

Perianal Crohn's disease.

A 13-year-old girl with a history of 4 months of perianal skin lesions is described. Physical examination revealed three 0.5 I 1-cm red, swollen, fleshy, skin tags extending from the perianal area to the perineum (Fig. 1). The patient reported intermittent fever, diarrhea, and abdominal pain, and her body weight was below the third percentile for her age. Laboratory studies showed an erythrocyte sedimentation rate of 101 mm/h; hematocrit of 26%; white blood cell count of 9800/mm3; serum iron of 15 mg/L (normal value (NV), 60-160 mg/L); ferritin of 43.4 microg/L (NV, 12-150 microg/L); transferrin of 203 mg/100 mL (NV, 200-400 mg/100 mL); transferrin saturation of 6% (NV, 20-50%); hypoalbuminemia; negative purified protein derivative (PPD), cytomegalovirus (CMV), human immunodeficiency virus (HIV), venereal disease research laboratory (VDRL), and antinuclear antibody tests; and Toxoplasma titers of 1/16, Van de Kamer 1.67 g/day. A barium examination revealed marked irregularity of the descending colon, and a colonoscopy showed uneven areas of mucosal edema and pseudopolyps in the transverse and descending colon, associated with irregular thickening and stenosis. Histopathologically, large intestine and skin lesions consisted of noncaseating epithelioid and giant cell granulomas (Fig. 2). Cultures for acid-fast bacilli and fungi were negative, and under polarized light no foreign bodies were seen. Treatment with metronidazole (250 mg three times a day), prednisone (0.5 mg/kg/day), and acetylsalicylic acid (75 mg/kg/day) was moderately effective. Vitamin, folic acid, and iron supplements were also added.

Adolescent↗
PubMed1993

Continuing trends in the prevalence of right-sided lesions among colorectal carcinomas.

The shift of colorectal carcinoma location toward the proximal colon has been reported. This study documents that this statistically significant trend has continued through 1992. An increase in transverse and descending colon cancers is now apparent also. Only 59% of all large-bowel cancers occurred distal to the descending colon between 1978 and 1992. Both right-sided and distal large-bowel cancers have significantly decreased in size, yet the incidence and frequency of lymph node metastases have not changed over a 65-year interval (from 1928 to 1992). This constant proportion of lymph node metastases may suggest distinct biological subsets of cancers (lymph node avid vs lymph node avoidance). The progression from small size with fewer metastases to large size with more lymph node metastases occurs only in some of the smallest distal colorectal cancers.

Boston↗
PubMed2000

Application of an object-oriented programming paradigm in three-dimensional computer modeling of mechanically active gastrointestinal tissues.

The aim of this study was to develop a novel three-dimensional (3-D) object-oriented modeling approach incorporating knowledge of the anatomy, electrophysiology, and mechanics of externally stimulated excitable gastrointestinal (GI) tissues and emphasizing the "stimulus-response" principle of extracting the modeling parameters. The modeling method used clusters of class hierarchies representing GI tissues from three perspectives: 1) anatomical; 2) electrophysiological; and 3) mechanical. We elaborated on the first four phases of the object-oriented system development life-cycle: 1) analysis; 2) design; 3) implementation; and 4) testing. Generalized cylinders were used for the implementation of 3-D tissue objects modeling the cecum, the descending colon, and the colonic circular smooth muscle tissue. The model was tested using external neural electrical tissue excitation of the descending colon with virtual implanted electrodes and the stimulating current density distributions over the modeled surfaces were calculated. Finally, the tissue deformations invoked by electrical stimulation were estimated and represented by a mesh-surface visualization technique.

Biomechanical Phenomena↗
PubMed2005

Assessment of large bowel motility by cine magnetic resonance imaging using two different prokinetic agents: a feasibility study.

OBJECTIVES: We sought to assess large bowel motility, induced by 2 prokinetic agents, senna tea and erythromycin, using functional cine magnetic resonance imaging (MRI). MATERIALS AND METHODS: Twelve volunteers underwent functional cine MRI before and after the administration of senna tea or erythromycin. The protocol consisted of 2 sets of repeated measurements using coronal T2-weighted HASTE sequences, adjusted to the course of the colon. For the assessment of large bowel motility, the changes of the luminal diameter were measured at 5 defined locations in the ascending, transverse, and descending colon. RESULTS: In all examined volunteers after senna tea, the mean number of significant changes in the ascending colon was 8.6 and after erythromycin, 7.2. In the transverse colon, 9.6 diameters changed significantly for senna tea and 7.2 for erythromycin. In the descending colon, 6.6 diameters changed after senna tea and 7.2 after erythromycin. CONCLUSION: Senna tea and erythromycin proved to induce large bowel motility; senna tea was more effective. Functional cine MRI is a reliable, noninvasive method for the assessment of colonic motility.

Administration, Oral↗
PubMed1996

Natural history of aberrant crypt foci. A surgical approach.

BACKGROUND: The aberrant crypt focus (ACF) appears to be an important early step in colorectal carcinogenesis. Our objectives were to determine the natural history of ACF in a surgical model. METHODS: The natural history of ACF was followed by marking the lesions in vivo with tattoos. Rats were given four weekly injections of azoxymethand (AOM; 20 mg/kg). One hundred days after the first injection of AOM, rats were anesthetized, and individual aberrant crypt focus was identified by staining with methylene blue. A 3 x 3 mm area, identifying one large (4-8 crypts) ACF was marked with a tattoo dye in each colon. Control animals received saline or AOM injections and were tattooed in areas without ACF. At 200 days, colons were examined for the presence of macroscopic lesions. RESULTS: A total of 54 tumors were found in the study group of 38 animals, and 21 of these were in the transverse and proximal descending colon. The marked areas (all in transverse and proximal descending colon) yielded 6 tumors and 2 ACF, but in 30 instances no abnormality was noted. Probability of observing a tumor in the 3 x 3 mm area of the colon that was identified as containing ACFs was 17 times greater than expected from the observed tumor rate in approximately the same zone (16 vs. 1.7 percent; 95 confidence interval, 10 to 22 and 0.5 to 1.3 percent). Twenty control animals receiving saline had no tumors of epithelial origin. Nine control animals that were carcinogen-treated and tattooed in areas without ACF had no tumors in the marked areas. CONCLUSION: Results thus show regression of many ACF identified early in the carcinogenesis process. Results also support the hypothesis that some ACF are precursor lesions for adenomas and cancers.

Adenoma↗
PubMed2005

Rare association of severe hypoplasia of the abdominal aorta with imperforate anus, colonic atresia, and choledochal cyst.

Hypoplasia of the abdominal aorta (HAA) is a rare condition that causes marked hypertension. Although multiple etiologies have been postulated for HAA, congenital structural anomalies are rarely observed except in cases associated with some hereditary syndromes. The authors describe a neonatal case with HAA complicated by multiple anomalies including colonic atresia (CA), imperforate anus, choledochal cyst, facial cleft, and brain defects. This patient showed CA in the descending colon and caliber change in the transverse colon mimicking Hirschsprung disease, both of which were thought to be caused by vascular insult to the mesentery due to HAA. Although multiple surgical corrections were successfully performed, the hypertension was uncontrollable.

Abnormalities, Multiple↗
PubMed1994

[A case-control study on colorectal cancer and dietary fiber and calcium of various sources].

A population-based case-control study was conducted in 726 incident cases with colorectal cancer and 1400 controls matched on age and sex in Shanghai, to explore the possible difference in associations between colorectal cancer and dietary fiber and calcium of various sources. The results showed reverse correlation between intake of vegetable fiber and ascending and descending colon cancer and rectal cancer, and between intake of fruit fiber and ascending colon cancer only. Dietary intake of calcium from animal sources could reduce the relative risk of ascending and descending colon cancer. These associations still existed after adjustment of the effects of the factors such as age, sex, intakes of total calorie, vitamin C, saturated fatty acid, etc. with logistic regression model, which indicated all of those variables were independent of other ones. Intake of dietary fiber from grains and calcium from plant sources had no significant protection from colorectal cancer. This study also showed the protective effects of dietary fiber and calcium on colorectal cancer not only correlated to their intake, but also closely to their sorts and sources.

Adult↗
PubMed2003

Scirrhous colonic metastasis from ductal carcinoma of the breast: report of a case.

Metastasis of breast cancer to the colon is rare. We report a case of a 49-year-old female who presented with a stenotic tumor of the descending colon five years after treatment of breast cancer with mastectomy and pedicled transverse rectus abdominis musculocutaneous flap. Laparotomy showed a diffusely infiltrated tumor over the descending colon. Anterior resection with loop ileostomy was performed, and the pathology showed that the colonic wall and the mesentery were diffusely infiltrated with poorly differentiated adenocarcinoma, which stained strongly for cytokeratin 7. The histologic diagnosis is consistent with colonic metastasis from ductal carcinoma of breast origin. In a patient with a history of breast cancer, colonic metastasis from the breast primary cancer should be considered, especially if the colonic lesion is scirrhous in nature. The incision for laparotomy and the probable stoma site should be planned carefully in females after breast reconstructive surgery.

Adenocarcinoma, Scirrhous↗
PubMed1983

Colonic perforation after corticosteroid and surgical treatment of intervertebral disk disease in a dog.

Colonic perforation after corticosteroid and surgical treatment of intervertebral disk disease in a dog Perforation of the distal segment of the descending colon, after corticosteroid and neurosurgical treatment for an intervertebral disk herniation, resulted in the death of a 3-year-old, male, Lhasa Apso. Initially, the dog was paraparetic in the hindlimbs, but became paraplegic after 4 days of conservative treatment. Corticosteroids were administered before referral and during decompressive hemilaminectomy. Six days after surgery, the dog had improved neurologically, but was depressed, anorectic, and vomiting. Abdominocentesis revealed septic peritonitis. The dog died shortly after a perforation in the descending colon was surgically corrected.

Adrenal Cortex Hormones↗
PubMed2002

Laparoscopic-assisted resection of giant sigmoid lipoma under colonoscopic guidance.

Colonic lipomata are rare and mostly asymptomatic lesions; but as they become larger they may produce abdominal pain, constipation, diarrhea, hemorrhage, and intussusception. We report the case of a 75-year-old man who suffered from nonspecific recurrent abdominal pain in the left upper and lower quadrants and had variable episodes of diarrhea and constipation of 4 weeks' duration. During colonoscopy, a giant intraluminal polyp was diagnosed at 35 cm. Abdominal helical computed tomography (CT) revealed a constipating colonic tumor with a diameter of >or=50 mm and density values equal to fat. During laparoscopic surgery in the lithotomy position, the sigmoid and the descending colon were mobilized using a Harmonic scalpel. The origin of the polyp was localized precisely under colonoscopic guidance. The former 12-mm incision in the left lower quadrant was expanded to approximately 70 mm for extracorporal tumor resection. The left and sigmoid colon resections were carried out, and the polyp was removed by full-wall excision. After closure with a single-layer suture, the colon was pushed back into the peritoneal cavity. The patient had an uneventful recovery and was discharged 10 days postoperatively. Histology confirmed a benign lipoma of the descending colon. Laparoscopic-assisted resection under endoscopic guidance proved to be suitable for the removal of large colonic polyps without complications.

Aged↗
PubMed1990

Role of prostaglandins and calcium in the effects of Entamoeba histolytica on colonic electrolyte transport.

We have previously shown that Entamoeba histolytica lysates contain the neurohormones serotonin, neurotensin, immunoreactive substance P, and probably acetylcholine, and that amebic lysates inhibit sodium and chloride absorption and stimulate chloride secretion in the rat descending colon as measured by the Ussing chamber-voltage clamp technique. We now demonstrate that these transport effects have both calcium-dependent and calcium-independent components. In addition, arachidonic acid metabolites of the cyclooxygenase pathway are probably involved in the Entamoeba histolytica-induced changes in colonic transport that are not dependent on Ca++ entry. Prostaglandin E2 (10(-5) M), indomethacin (10(-6) M), piroxicam (5 x 10(-5) M), and mepacrine (10(-4) M) partially inhibited the amebic lysate effect on active transport in the rat descending colon. In addition, verapamil (10(-4) M) partially inhibited the effect of amebic lysates. The effect of verapamil was additive with that of indomethacin, totally blocking the effect of amebic lysate on short-circuit current. However, amebic lysates do not contain prostaglandin E2 as measured by sensitive radioimmunoassay. Amebic lysates stimulated prostaglandin E2 release from rat colonic mucosal strips. Amebic lysate significantly increased colonic cyclic adenosine monophosphate content. Piroxicam inhibited the lysate-induced increase in colonic cyclic adenosine monophosphate content. These results indicate that although amebic lysate does not contain prostaglandin E2, it caused arachidonic acid metabolites to be produced by the cyclooxygenase pathway, and these are probably involved in the Entamoeba histolytica-induced changes in colonic transport. Neurohormones in Entamoeba histolytica may act directly on colonic tissue to stimulate intestinal secretion, probably via a Ca+(+)-dependent mechanism that is blockable by verapamil, or indirectly via stimulation of prostaglandin E2 generation and release from the rat colon via a cyclic adenosine monophosphate-dependent mechanism. These effects appear separate. The cyclic adenosine monophosphate-dependent secretion is the predominant mechanism in this model of colonic amebic diarrhea.

Amebiasis↗