Search results for "Colon"
showing 10 items of 2038 documents
Pharmacological investigation into the effects of histamine and histamine analogues on guinea-pig and rat colon in vitro.
1986
The effects of histamine and specific histamine agonists has been examined on isolated longitudinal colon strips of guinea-pig and rat. Histamine and 2-pyridyl-ethylamine but not 4 methylhistamine produced a concentration-related contractile response in the guinea-pig colon. The H1-antagonist clemizole antagonized competitively the effect of histamine but the H2-antagonist ranitidine did not modify the dose-response curve to histamine in the guinea-pig colon. Atropine, hexamethonium, prazosin and propranolol failed to modify the contractile response to histamine. Tone induced with KCl in guinea-pig isolated colon was not modified by histamine agonists even in tissues pretreated with clemizo…
Rhein stimulates active chloride secretion in the short-circuited rat colonic mucosa.
1988
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,…
Identification of α2-adrenoceptors and non-adrenergic idazoxan binding sites in rabbit colon epithelial cells
1990
alpha 2-Adrenoceptors are possibly involved in the regulation of the hydroelectrolytic flux across the digestive mucosa. As no data are available concerning the existence of these receptors in colon epithelial cells, we aimed to investigate the existence of alpha 2-adrenoceptors in this tissue using tritiated antagonists. [3H]Yohimbine and [3H]rauwolscine were not usable to label colonic alpha 2-adrenoceptors because of their very high level of non-specific binding. In contrast, the methoxy derivative of idazoxan, [3H]RX821002, appeared a convenient radioligand for the purpose. [3H]RX821002 bound with high affinity (KD = 6.2 +/- 0.8 nM) to a single population of non-interacting sites (Bmax …
Effect of the stable prostacyclin analogue iloprost on water and electrolyte transfer of the rat ileum and colon in vivo.
1988
The effect of iloprost on water and ion transfer was measured simultaneously in tied-off loops of the rat ileum and colon in vivo. (1) In the ileal loops iloprost had no effect on water and ion transfer neither by intraluminal, nor intraaortal or intravenous application. (2) In the colonic loops only intraaortal bolus application of the high dose of 500 micrograms iloprost significantly decreased net water, sodium and chloride absorption, but did not induce net secretion. (3) Inhibition of endogenous prostaglandin synthesis by indomethacin did not change net water and electrolyte transfer in the ileum and colon. (4) Under this pretreatment i.v.-application of 100 micrograms iloprost, ineffe…
Intestinal filtration as a consequence of increased mucosal hydraulic permeability
1980
Two mechanisms have been proposed to explain the secretory action of laxative compounds in the intestine: 1. increase of the intracellular amount of cyclic adenosine monophosphate due to stimulation of the adenylate cyclase system and 2. inhibition of intestinal transfer processes, in particular the Na,K-ATPase activated sodium absorption. In a set of in vivo and in vitro experiments in rat colon it could be demonstrated that dihydroxy bile acids (deoxycholate) and diphenolic laxatives (oxyphenisatin) enhance the hydraulic permeability of the mucosal tissue. The permeability changes take place--and there is good experimental evidence--at the zonulae occludentes which bind the epithelial cel…
Oral administration of taurolidine ameliorates chronic DSS colitis in mice.
2007
Taurolidine (TRD) has antimicrobial and anti-inflammatory properties. However, the anti-inflammatory effects of TRD in inflammatory bowel diseases (IBD) have not been investigated. Here, we have analyzed the toxicity of TRD after oral long-term application in mice and examined the impact of oral TRD in a dextran sulfate sodium (DSS) model of experimental colitis. Female C57/BL6 mice received TRD in various concentrations (0.1% to 0.4%) for 60 days. Toxicity was evaluated by use of a disease activity index (DAI) and histological examination of major metabolic organs. Furthermore, the impact of 0.2% TRD on a chronic DSS colitis was examined by daily DAI, histological crypt damage score (CDS),…
Bladder augmentation and urinary diversion in patients with neurogenic bladder: Non-surgical considerations
2011
Segments from almost all parts of the bowel have been used for urinary diversion. As a result, the available absorptive surface area of the bowel is reduced, and the incorporation of bowel segments into the urinary tract may have metabolic consequences. This is an area somewhat neglected in the literature. Metabolic complications are rare, but sub-clinical metabolic disturbances are quite common. Several studies have demonstrated that some of the absorbent and secreting properties of the bowel tissue are preserved after incorporation into the urinary tract. Hyperchloraemic metabolic acidosis can occur if ileal and/or colon segments are used, as well as malabsorption of vitamin B(12) and bil…
Role of fluorine 18 fluorodeoxyglucose positron emission tomography/computed tomography in gastrointestinal cancers
2015
AbstractFluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) has become a routine imaging modality for many malignancies and its use is currently increasing. In the present review article, we will summarize the evidence for FDG-PET/CT use in digestive cancers (excluding neuroendocrine tumours), and review the existing recommendations. While PET/CT is nowadays considered to be an important tool in the initial workup of oesophageal and anal cancers, new data are emerging regarding its use in assessing therapeutic efficacy, radiotherapy treatment planning, and detection of recurrence in case of isolated tumour marker elevation. Moreover, PET/CT may help …
Virtual chromoendoscopy with iSCAN as an alternative method to dye-spray chromoendoscopy for dysplasia detection in long-standing colonic inflammator…
2021
Patients with long-standing colonic inflammatory bowel disease (cIBD) are at increased risk of developing colorectal cancer (CRC). Dye-spray chromoendoscopy (DCE) with targeted biopsies is the preferred technique for surveillance of dysplasia. Virtual chromoendoscopy (VCE) are arising to improve detection rates and adherence to surveillance guidelines, although its role is not yet well defined. The purpose of this study is to assess the effectiveness of VCE with iSCAN as an alternative method for dysplasia detection in cIBD.Retrospective case-control study with 191 patients included, 98 in the DCE (Indigo carmine) group and 93 in the VCE (iSCAN, twin-mode 1-3) group. The dysplasia detection…
Feasibility and Safety of Laparoscopic Complete Mesocolic Excision (CME) for Right-sided Colon Cancer
2020
OBJECTIVE The aim of this prospective clinical study is to compare short-term outcome of laparoscopic right hemicolectomy using the Complete Mesocolic Excision (CME group) with patients who underwent conventional right-sided colonic resection (NCME group). SUMMARY BACKGROUND DATA Although CME with central vascular ligation in laparoscopic right hemicolectomy is associated with a significant decrease in local recurrence rates and improvements in cancer-related 5-year survival, there may be additional risks associated with this technique because of increased surgical complications. As a result, there is controversy surrounding its use. METHODS In this randomized controlled trial, several prim…