Endoscopic and percutaneous treatment of benign biliary strictures is not only a short-term treatment, but also an adequate long-term therapeutic alternative to surgery, with tolerable complication rates. The period of stenting appears to influence the outcome, and the diameter of the stents used also probably plays a role. Prospective studies are required for further evaluation of these observations.
The nitric oxide (NO) signaling pathway is a major nonadrenergic-noncholinergic transmitter mechanism in the enteric nervous system. Our aim was to localize the enzymes in question, i.e., neuronal nitric oxide synthase (nNOS), soluble guanylate cyclase (sGC), and cGMP-dependent kinase type I (cGK-I) in rat small intestine by indirect immunofluorescence. nNOS staining was found in neurons of the myenteric plexus and in varicose nerve fibers mainly in the circular muscle layer. The cells positive for neurokinin-1 (NK-1) receptor and c-kit (interstitial cells of Cajal, ICC) in the deep muscular plexus (DMP) did not show nNOS reactivity, but nNOS-positive nerve fibers were directly adjacent to them. sGC was found in flattened cells surrounding myenteric ganglia (periganglionic cells, PGC), in ICC of the DMP, faintly in smooth muscle cells (SMC), and in cells perivascularly scattered throughout the circular muscle layer. cGK-I immunoreactivity was found abundantly in PGC (which presumably are ICC), in ICC of DMP, in SMC of the innermost circular and longitudinal muscle layers, but less intensively in the outer circular layer. Weak cGK-I staining occurred in nerve cells within the myenteric and submucosal plexus. Conclusively the key enzymes of the NO signaling pathway are differentially distributed: Occurrence of nNOS exclusively in neurons and the presence of sGC and cGK-I predominantly in ICC suggest a sequence of neuronal NO release, activation of ICC, and consecutive smooth muscle relaxation. ICC of the DMP seem to be the primary targets for neurally released NO.
The most common pancreatic tumour is the ductal adenocarcinoma. Many other benign and malignant pancreatic neoplasms have to be recognised and now account for more than 50 % of the pancreatic lesions seen in our daily routine. An improved differential diagnosis is, therefore, mandatory and will be discussed in this review.
Around 10-20% of the population suffer from the hallmark symptoms of heartburn, regurgitation, sour burping and retrosternal pain. Based on their characteristic medical history alone, such patients can usually be presumed to have gastroesophageal reflux disease (GERD). In around 30-50% of them, the endoscopic examination will reveal the typical erosions and ulcerations in the esophagus. In addition to the clinical symptoms, endoscopy plays a central role in diagnosing GERD. An endoscopy is always indicated whenever these warnings symptoms are present. In patients with persistent reflux problems, endoscopy is indicated to diagnose erosive reflux esophagitis. This procedure should include a routine biopsy taken distal to the Z-line to enable histological detection of the metaplasia associated with Barrett's esophagus. Although the majority of patients exhibit the classical symptoms and respond to acid suppression therapy, endoscopy may not find erosions (non-erosive reflux disease NERD). In these cases, further diagnostic steps must be taken to verify the diagnosis of gastroesophageal reflux disease. There are patients, moreover, who exhibit unclear, uncharacteristic reflux symptoms, such as respiratory diseases with bronchial asthma, chronic bronchitis, chronic cough or ENT problems like posterior laryngitis and globus sensation (a lump in the throat). In these uncertain cases and in patients with NERD, 24-hour pH monitoring can verify and objectify and acid gastroesophageal reflux. An association can then be made between acid reflux and symptomatology. As an alternative, trial therapy with a proton pump inhibitor can help identify patients who have acid-related problems and symptoms. Other functional tests such as radiographic examination, manometry or scintigraphy are less well suited, if at all, for primary diagnostics of gastroesophageal reflux disease.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.