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PubMed1992

[Resection of the sigmoid via laparoscopy: an experimental study of its feasibility].

The authors describe an experimental laparoscopic sigmoid colon resection performed in the porcine model. The operation begins with the introduction of the laparoscope via an umbilical trocar. Five other trocars are then placed allowing different maneuvers. The sigmoid colon is grasped in order to gain access to its mesenteric vessels which are clipped and divided, carrying out the dissection of the entire sigmoid colon. Two modified Endo-GIA are then fired both cranially and caudally, in order to obtain a closed sigmoid specimen and to maintain patent the lumen of the descending colon and rectum. The sigmoid is removed transanally. A P-CEEA stapler is introduced via the rectum and its detached anvil is put into the lumen of the descending colon. A purse-string is applied and closed around the anvil rod. The P-CEEA is retracted, and the rectal stump closed with another Endo-GIA. After reintroducing the trocar-loaded stapler, the trocar is advanced through the suture line of the rectum and removed via a port. The stapler is then reassembled, fired and extracted through the anus. Taking into account the oncologic criteria, we think that this mini-invasive technique could be applied, after an adequate training period on the animal model, to humans also.

Anastomosis, Surgical↗
PubMed2004

[A case of metachronous carcinoma of the colon diagnosed and radical operated with restorative anastomosis after more than 5 years from the first left hemicolectomy].

The authors described their observation about the female patient with an advanced carcinoma (T4) of the descendent colon where left hemicolectomy was done in the beginning of 1998. The patient is operated again after more than 5 years because of the cancer in the site of the anastomosis. Radical reresection with restorative anasomosis is performed and for this reason the colon is putting via mesenteric radix. The case is analyzed and there are suggestion about is this a local recurrence or "de novo" carcinoma It is important to follow up the patients during lifetime for early uncovering of local recurrence. Endocoloscopy and scener are preferable for this aim.

Adenocarcinoma↗
PubMed1996

Selective inhibition of neuropeptide Y Y1 receptors by BIBP3226 in rat and human epithelial preparations.

BIBP3226 (N2-(diphenylacetyl)-N-[4-hydroxyphenyl)methyl]-D-arginine amide) has been used to examine the presence of neuropeptide Y Y1 receptors in 3 gastrointestinal epithelial preparations, namely the rat jejunum and descending colon mucosae and a human colonic adenocarcinoma cell line. The selective Y1 receptor antagonist (1 microM BIBP3226) had no significant effect upon either peptide YY (PYY) responses or on electric field stimulated changes in electrogenic ion transport in rat jejunum mucosa. Partial inhibition of PYY responses was observed following BIBP3226 pretreatment of rat colon mucosal preparations in the presence and absence of tetrodotoxin. Responses to the Y1 selective agonist [Leu31,Pro34]neuropeptide Y ([Leu31, Pro34]NPY) in descending colon preparations were significantly attenuated by BIBP3226 (1 microM). The same concentration of antagonist abolished responses to PYY and [Leu31,Pro34]NPY but had no effect upon human pancreatic polypeptide (hPP) in monolayer cultures of the human adenocarcinoma cell line, Colony-6. Schild analysis of BIBP3226 antagonism of PYY responses in Colony-6 cells provided a pA2 value of 7.9 with a Hill slope of 1.03, indicating competitive antagonism at these epithelial Y1 receptors.

Animals↗
PubMed2001

Colitis cystica profunda.

A 39-year-old woman with inflammatory bowel disease was admitted to the hospital because of cramping abdominal pain and diarrhea. Ultrasound of the abdomen revealed thickening of the wall of the descending colon. At endoscopy mucosa-covered nodules with substenosis were seen. A double-contrast examination showed narrowing in the transition zone between the descending colon and sigmoid with mucosal nodularities and barium spots in between. Examination of the resection specimen revealed colitis cystica profunda. After surgical treatment the history of the patient was uneventful.

Adult↗
PubMed2000

[Rheumatoid vasculitis with multiple intestinal ulcerations: report of a case].

Rheumatoid vasculitis is a relatively uncommon complication of rheumatoid arthritis (RA). It shows wide variety of extra-articular features including skin and neurologic involvement, but rarely shows gastrointestinal involvement. We describe a 79-old-man of rheumatoid vasculitis manifesting as small bowel multiple ulcerations accompanied by perforation of the descending colon diverticulum. The patient was admitted to our hospital with rectal bleeding and severe anemia. He had had rheumatoid arthritis for more than 10 years with treatment of non-steroidal anti-inflammatory drugs (NSAIDs) and low-dose prednisone. Upper endoscopy or colonoscopy revealed no evidence of bleeding. Suddenly he developed cramping abdominal pain, and emergency operation was performed. Segments of the descending colon and small bowel were resected to reveal perforation of the descending diverticulum and severe multiple ulcer of small bowel. The pathological examination showed multiple ulcerations of the small intestine was caused by vasculitis.

Aged↗
PubMed2003

Surgical treatment of noncommunicating duplication of the colon in a dog.

A 4-month-old sexually intact male Jack Russell Terrier was evaluated because of stranguria and tenesmus. A tubular abdominal mass was palpable abdominally and rectally. Radiographic examination of the abdomen revealed a soft tissue mass located laterally and to the left of the descending colon, which was associated with extraluminal colonic obstruction and urethral compression. During abdominal exploratory surgery, a large cystic mass that was adhered to the antimesenteric border of the descending colon was removed. Porcine small intestinal submucosa was used to reinforce repair of the excision site. Histologic examination of samples of excised tissue identified normal colonic epithelium supported by submucosa and muscular tunics, which was consistent with duplication of the colon. The embryologic etiology of alimentary duplication is poorly understood, and colonic duplication is an extremely rare congenital anomaly.

Animals↗
PubMed1972

Mass peristalsis in the human colon after contact with oxyphenisatin.

Colonic motility studies using time-lapse cinefluorography and intraluminal pressure recording before and after the introduction per rectum of a mixture of barium sulphate and oxyphenisatin solution show the different forms of movement of the colonic contents. Oxyphenisatin was found to be a selective actuator of a form of progressive mass propulsion indistinguishable from spontaneous mass peristalsis. Less than 0.5 mg distributed through the pelvic and distal descending colon was enough to produce a peristaltic response; larger quantities tended to increase the number of resulting movements.A standard dose of 4 mg of the drug was followed by mass peristalsis in 82% of the subjects in whom it came into adequate contact with colonic mucosa. The response usually took place within 20 minutes. The more sensitive the subject, the greater was the number of peristaltic responses and the shorter the interval before the response began. In 73% of the subjects who responded, the mass peristalsis came to a halt between 40 and 25 cm from the anal margin, and many of those in whom it extended farther appeared to have shortened distal colons. The likelihood of the drug giving rise to peristalsis diminished abruptly distal to about 45 cm from the anus; its effectiveness was greatest in the proximal descending colon.

Barium Sulfate↗
PubMedDate not supplied

J.J. Bonica Lecture--2000: Physiology, pathophysiology, and pharmacology of visceral pain.

BACKGROUND AND OBJECTIVES: The principal objective of this report is to review recent experimental advances in our understanding of the physiology and pathophysiology of visceral pain and to describe results of studies of opioid modulation of visceral nociception. METHODS: Results are drawn from electrophysiological studies of single pelvic nerve afferent fibers innervating the descending colon in the rat. RESULTS: The important findings include the following: identification of a subset of pelvic nerve fibers that likely function to signal acute visceral pain, sensitization of mechanosensitive pelvic nerve fibers, and documentation of the presence of silent nociceptors in the pelvic nerve. With respect to pharmacological modulation of pelvic nerve fiber responses to colonic distension, only kappa-opioid receptor agonists, and not mu- or delta-opioid receptor agonists, were effective. CONCLUSIONS: All pelvic nerve fibers innervating the descending colon can be sensitized and contribute to visceral pain; their responses are modulated by kappa-opioid receptor agonists acting in the periphery.

Animals↗
PubMed1999

Protein kinase A regulatory subunits in colon cancer.

The protein kinase A (PKA) is classified as type I or II depending on the association of the catalytic subunit with either the R(I) or R(II) regulatory subunits. Alterations in the levels of these regulatory subunits and PKA activity itself appear to affect cellular proliferation and tumorigenesis. We examined colorectal tumor specimens from 45 patients to investigate the potential role of cAMP-related signaling molecules in regulating tumorigenesis. Western blot analysis (PKA subunit protein levels) and in vitro kemptide phosphorylation assays (PKA catalytic subunit activity) were performed on human colorectal tumor tissue homogenates. R(I)beta protein levels were decreased 200% in ascending and 50% in descending colonic tumors compared to adjacent mucosa. R(II) protein levels were decreased 77% in descending colonic tumors but no change was observed in ascending colonic tumors compared to adjacent mucosa. PKA activity and the absolute amount of catalytic subunit protein in ascending and descending tumors were unchanged compared to adjacent mucosa. Differences in cAMP-related signaling molecules exist between neoplastic and normal colorectal tissues. These differences may not only serve as potential therapeutic targets for chemotherapeutic agents, but also lead to the identification of novel regulatory mechanisms involved in cellular proliferation and tumorigenesis.

Adult↗
PubMed1996

Distribution of mesalazine enemas in active and quiescent ulcerative colitis.

BACKGROUND: The efficacy of mesalazine enemas depends on intraluminal concentration of the drug and is therefore limited by the enema distribution in the colon. Active ulcerative colitis changes colon motility and this leads to uncertainty about enema spread. AIM: To assess the influence of disease activity on enema distribution, we conducted a physician-blinded, longitudinal study of the retrograde spread of three mesalazine enemas. METHODS: Thirty-one patients with mild to moderate ulcerative colitis were subdivided into three groups, and treated with 2 g mesalazine in 30 mL (group I, n = 10), 4 g mesalazine in 60 mL (group II, n = 12) or 1 g mesalazine in 100 mL (group III, n = 9). All patients received oral mesalazine 500 mg t.d.s. Enemas were labelled by adding 10 MBq (99mTc)technetium-sulphur colloid. Anterior scintigraphic images were taken at the start of the study and after 12 weeks of therapy; retrograde spread was assessed by calculating the percentage of the enema in each colonic segment. RESULTS: The activity score of ulcerative colitis diminished significantly after 12 weeks of treatment, but five patients dropped out of the study. At the start of treatment enema activity in group I was mainly concentrated in the sigmoid (99%); in group II activity was found in the rectum (9%), the sigmoid (61%) and the descending colon (15%); in group III activity was distributed between the sigmoid (66%) and descending colon (25%). The colonic distribution of mesalazine enemas was not influenced by disease activity. CONCLUSION: Volume, but not disease activity, is the important determinant of retrograde colonic spread of mesalazine enemas in ulcerative colitis.

Adult↗
PubMed1998

[Protective effect of glutamine on microcirculation of the intestine in experimental colitis].

Parenteral glutamine application can stabilize intestinal permeability and mucosal integrity. It is not known whether glutamine influences the microcirculation in the large intestine. This study thus employs intravital microscopy to investigate mucosal microcirculation in the ascending and descending Colon of Sprague-Dawley rats with TNBS colitis. The animals were randomized and treated with either saline solution (placebo) or glutamine (verum). In the severely inflamed descending colon, TNBS colitis involves a significant capillary blood flow reduction that is not improved by glutamine application. Though the ascending colon shows only a mild inflammatory reaction, its microcirculation is likewise significantly reduced. Here glutamine therapy is associated with an increase in capillary blood flow, indicating that it has a protective effect on the microcirculation of the secondarily involved intestinal segment.

Animals↗
PubMed1988

Distribution, quantitation, and origin of immunoreactive neuropeptide Y in the human gastrointestinal tract.

A radioimmunoassay for measurement of immunoreactive neuropeptide Y has been developed using antiserum from a rabbit (221) immunized with porcine neuropeptide Y. Antibody 221 has been characterized for both sensitivity and specificity. To determine the distribution of neuropeptide Y in the human gastrointestinal tract, fresh tissue specimens were separated by microdissection into the muscularis externa and the mucosa-submucosa. To examine the origin of neuropeptide Y in human colon, specimens of aganglionic and ganglionic colon were obtained from patients with Hirschsprung's disease. Immunoreactive neuropeptide Y in human gut was present in highest concentrations in the muscularis externa of the stomach and in lowest concentrations in the muscularis externa of the ileum and descending colon. Neuropeptide Y in the stomach was present in higher concentrations in the muscularis externa than in the mucosa-submucosa, but in the descending colon there were lower concentrations of neuropeptide Y in the muscularis externa than in the mucosa-submucosa. In Hirschsprung's disease, concentrations of neuropeptide Y were increased in aganglionic colon in both the muscularis externa and the mucosa-submucosa, compared to corresponding layers from proximal ganglionic colon. Extracts of the gastric muscularis externa and the colonic mucosa-submucosa were separated by C18 reverse-phase high-performance liquid chromatography. One major immunoreactive species was identified by radioimmunoassay which eluted in a position similar to synthetic human neuropeptide Y. These results demonstrated both regional and layer differences in concentrations of neuropeptide Y in human gut. Increased concentrations of neuropeptide Y in aganglionic colon from Hirschsprung's disease most likely result from enlargement of neuropeptide Y-containing extrinsic nerve fibers in both the mucosa-submucosa and the muscularis externa.

Animals↗
PubMed1978

Effect of aldosterone on ion transport by rabbit colon in vitro.

Segments of descending colon obtained from rabbits, that had been maintained on drinking water containing 25 mM NaCl and an artificial diet which contains 1% Na and is nominally K-free, respond to aldosterone in vitro (after a 30 to 60-min lag period) with a marked increase in the short-circuit current (Isc), an equivalent increase in the rate of active Na absorption (JNa net) and a decline in tissue resistance (Rt). Aldosterone also brings about a marked increase in the unidirection influx of Na into the cells across the mucosal membrane ("zero-time" rate of uptake) which does not differ significantly from the inrease m Isc. Treatment of control tissues with amphotericin B brings about sustained increases in Isc and JNa net to levels observed in aldosterone-treated tissues. However, addition of amphotericin B to the mucosal solution of aldosterone-treated tissues does not result in a sustained increase in Isc or JNa net and these values do not differ markedly from those observed in control tissues treated with amphotericin B. These findings, together with other evidence that Na entry in the presence of amphotericin B is sufficiently rapid to saturate the active Na extrusion mechanism at the baso-lateral membrane, are consistent with the notion that the aldosterone-induced protein increases the permeability of the mucosal membrane to Na but does not increase the "saturation level" of the active Na "pump" within the time-frame of these studies (3 hr). Finally, aldosterone has no effect on the bidirectional or net transepithelial movements of K under short-circuit conditions, suggesting that the enhanced secretion of K observed in vivo is the result of increased diffusion of K from plasma to lumen via paracellular pathways in response to an increased transepithelial electrical potential difference (lumen negative).

Aldosterone↗
PubMed2003

Mucosal secretion and expression of basic fibroblast growth factor in patients with collagenous colitis.

OBJECTIVES: Collagenous colitis (CC), a condition of unknown ethiology and pathophysiology, is characterized by watery diarrhea and increased amounts of collagen in the colonic mucosa. Basic fibroblast growth factor (bFGF) is a potent multifunctional growth factor that stimulates proliferation and differentiation of fibroblasts that was recently detected in high intraluminal concentrations in patients with ulcerative colitis. In this study we examined the secretion and expression of bFGF in the colorectal mucosa of patients with CC. METHODS: Ten CC patients and 10 control patients underwent colonoscope-based segmental perfusion of the descending colon and rectum. The concentrations of bFGF in perfusate and serum were determined by immunochemical methods, and the expression of bFGF was analyzed immunohistochemically in biopsy samples from colonic mucosa. RESULTS: The median concentrations of bFGF in perfusates from the descending colon and rectum were increased 4-fold in CC patients compared with control patients. The median concentration of bFGF in serum was not significantly different in patients and controls. Immunohistochemical staining of bFGF was located in the colorectal epithelial cells and in exsudate on the luminal side of these cells. In the lamina propria, inflammatory cells and fibroblasts contained bFGF. There were no differences in the intensity of bFGF staining in surface epithelium or lamina propria between patients and controls. CONCLUSIONS: Local investigation of the colorectal mucosa seems to be crucial when studying the pathophysiology of CC. Increased colorectal mucosal secretion of bFGF in patients with CC may promote differentiation of fibroblasts and thereby lead to increased subepithelial collagen deposition.

Adult↗
PubMed1978

Left-sided colectomy with retroileal colorectal anastomosis.

Following resection of the sigmoid and descending colon for cancer or extensive diverticular disease, it may be impossible to make a colorectal anastomosis due to inadequate length of the residual transverse colon. To correct this problem, the remaining transverse colon may be pulled into the pelvis by making a "window" in the terminal part of the ileal mesentery. From January 1966 to January 1975, 302 resections of the descending colon with colorectal anastomoses were performed by one of the authors (R.B.T.) for upper sigmoid cancer and extensive diverticulitis at the Cleveland Clinic. Eleven patients (4%) had retroileal colorectal anastomoses. The retroileal apprach is a technical aid when performing an extensive left-sided colectomy and/or when there is insufficient length of residual transverse colon to make a tension-free colorectal anastomosis.

Adult↗
PubMed1993

Effect of a 5HT3-antagonist (ondansetron) on rectal sensitivity and compliance in health and the irritable bowel syndrome.

In some patients with the irritable bowel syndrome, rectal urgency and discomfort are major clinical problems and, under experimental conditions, these symptoms are perceived at lesser volumes of rectal distension than they are in asymptomatic controls. Further, a 5-hydroxytryptamine type-3 receptor antagonist increased the threshold for rectal discomfort in irritable bowel syndrome. Our aims were, (a) to measure rectal sensation during isobaric distensions of the rectum, and (b) to test the effect of another selective 5HT3-antagonist, ondansetron 0.15 mg/kg, on rectal sensitivity, colonic tone, rectal tone and manometric responses. Ten healthy volunteers and five patients with diarrhoea-predominant irritable bowel syndrome were studied. A multilumen barostat-manometric assembly was placed in the descending colon, and a second barostat balloon was positioned in the rectum. Tone in the wall of the colon and rectum was measured by the barostat balloon volume during a constant pressure clamp, while intraluminal pressures were recorded by manometry; perceived sensations were also recorded before and after the intravenous administration of ondansetron or placebo in blinded fashion. Rectal resistance to stretch was greater and rectal urgency was induced by lower distending pressures in irritable bowel syndrome, however, basal tone in the rectum was similar in health and irritable bowel syndrome. Ondansetron did not change rectal sensitivity (first sensation or urgency) or tone. Rectal distension did not alter tone in the descending colon or colonic manometry; ondansetron did not influence any index of colonic function.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2006

Serotonin-producing enterochromaffin (EC) cells of gastrointestinal mucosa in dexamethasone-treated rats.

The aim of our study was to investigate the morphological, immunohistochemical and ultrastructural changes of rat serotonin-producing enterochromaffin (EC) cells of gastrointestinal mucosa in dexamethasone-treated rats (D). After 12-daily intraperitoneal administration of 2 mg/kg dexamethasone, rats developed diabetes similar to human diabetes type 2. Stomach, small and large intestines were examined. Large serotonin positive EC cells appeared in the corpus mucosa epithelium of D group of rats, although these cells were not present in control (C) rats. Both volume fraction and the number of EC cells per mm(2) of mucosa were significantly increased only in the duodenum. However, the number of EC cells per circular sections of both antrum and small intestine was increased, but reduced both in the ascending and descending colon in D group. The dexamethasone treatment caused a strong reduction in number of granules in the antral EC cells, while it was gradually increased beginning from the jejunum to descending colon. The mean granular content was reduced in the antral EC cells but increased in the jejunal EC cells in D group. In conclusion, the present study showed that morphological changes in gut serotonin-producing EC cells occurred in diabetic rats.

Animals↗
PubMed2005

Morphology of myenteric plexuses in the human large intestine: comparison between large intestines with and without colonic diverticula.

BACKGROUND: Large intestines with diverticula exhibit functionally abnormal peristaltic activity and elevated luminal pressure that may indicate functional changes in the myenteric plexus; however, no studies have investigated the characteristics of either normal or diverticula myenteric plexuses. METHODS: Tissue specimens obtained from 93 colorectal cancer patients without diverticula, 14 patients with perforated diverticulitis, and 12 colorectal cancer patients with asymptomatic diverticula were included in this study. Myenteric plexuses and ganglion cells were counted per centimeter, and the area and maximum diameter of the nuclei of ganglion cells were measured using an image analyzer. RESULTS: The number of myenteric plexuses and ganglion cells per centimeter was significantly higher in the descending colon, sigmoid colon, and rectum than in the cecum, ascending colon, and transverse colon. The area of the nuclei of ganglion cells was significantly larger in the descending colon and sigmoid colon than in the cecum and ascending colon. Compared with large intestines without diverticula, the number of myenteric plexuses was significantly higher in large intestines with diverticula, whereas the number of ganglion cells decreased in both right-sided and left-sided large intestines with perforated diverticulitis or asymptomatic diverticula. The area of the nuclei of ganglion cells was significantly smaller in large intestines with diverticula. CONCLUSION: The morphology of myenteric plexuses and the ganglion cells differs significantly among segments of the human large intestine. Large intestines with diverticula had significantly more plexuses but significantly fewer ganglion cells than large intestines without diverticula. The area of the nuclei of ganglion cells was also significantly smaller in large intestines with diverticula. Further studies are required to clarify how these changes are related to intestinal function and how they are involved in the etiology of diverticulosis.

Adult↗