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Biomedical subjects

M Classen

Publications and source records attributed to M Classen.

At least 541 records · Page 30Linked to original sources
PubMedDate not supplied

Laser versus laser plus afterloading with iridium-192 in the palliative treatment of malignant stenosis of the esophagus: a prospective, randomized, and controlled study.

Thirty-nine patients with malignant stenoses of the esophagus (22 adenocarcinomas, 17 squamous cell carcinomas) were treated either with Nd:YAG laser recanalization alone (N = 20) or with laser recanalization and subsequent endoluminal afterloading irradiation with iridium-192 at a dose of 3 x 7 Gy (6 x 7 Gy). Squamous cell carcinoma patients in the afterloading group showed a prolonged dysphagia-free first interval (65 vs. 30 days, p less than 0.03), while patients with an adenocarcinoma did not share this benefit, and had a need for more frequent endoscopic procedures (p less than 0.05). The complication of esophagitis was only seen following afterloading treatment (21%, N = 4). Re-stenosis occurred in all patients. Neither the duration of relative dysphagia nor survival time was prolonged after endoluminal irradiation in adenocarcinoma or squamous cell carcinoma patients. After prior laser recanalization, palliative afterloading treatment with iridium-192 would seem helpful only in cases of squamous cell carcinoma with a high performance status with the aim of prolonging the first dysphagia-free interval.

Adenocarcinoma↗
PubMedDate not supplied

Evaluation of submucosal upper gastrointestinal tract lesions by endoscopic ultrasound.

The proper diagnosis of submucosal upper gastrointestinal tract mass lesions by endoscopy or barium study is difficult. Differentiation between submucosal tumors, vascular structures, and extrinsic organs is often impossible. We performed endoscopic ultrasound examination of 91 patients with upper gastrointestinal submucosal mass lesions. Endoscopic ultrasound was accurate in determining the site of origin in 48 of 50 cases where pathology or angiography comparison was available. Leiomyoma, lipoma, varices, and carcinoma had characteristic ultrasonographic findings. Endoscopic ultrasound is a useful procedure in the evaluation of upper gastrointestinal submucosal mass lesions.

Endoscopy, Gastrointestinal↗
PubMedDate not supplied

Local staging and assessment of resectability in carcinoma of the esophagus, stomach, and duodenum by endoscopic ultrasonography.

Eighty-eight patients with carcinoma of the esophagus (N = 44), stomach (N = 41), and duodenum (N = 3) who underwent surgery were pre-operatively examined by endoscopic ultrasonography (EUS). The ability of EUS to accurately predict the T stage and the N stage was 82% and 70% for esophageal carcinoma, 71% and 75% for gastric cancer, and 100% and 66% for duodenal malignancy. In esophageal carcinoma, the accuracy of T staging was only slightly lower in cases with non-traversable tumor stenoses (77%) compared with traversable carcinomas (84%). This was probably due to the fact that all non-traversable tumors were either in stage T3 or T4. The accuracy of EUS in predicting the stages T1 to T3, which correspond to R0 resectability (no macroscopic or microscopic tumor remains), was 92% for adenocarcinoma of the distal esophagus and 85% for gastric cancer. However, in squamous cell carcinoma of the esophagus, R0 resection was possible in only 66% of all cases, whereas EUS predicted an 84% R0 resection rate. In adenocarcinoma of the distal esophagus and stomach, EUS prediction of stages T1 to T3 correlated well with the actual rate of R0 resection. These results show that EUS is a reliable diagnostic method for the local staging of upper gastrointestinal cancer. Its impact on treatment and hence on prognosis of patients with these malignancies has yet to be determined.

Adenocarcinoma↗
PubMedDate not supplied

Primary sclerosing cholangitis in children.

Primary sclerosing cholangitis (PSC) in eight children, five males and three females between the ages of 4 and 13 years, presented with minimal clinical symptoms and few signs of liver disease. Diagnosis was made by a highly characteristic histology in all and additional endoscopic retrograde cholangiography (ERC) in four patients. Six children suffered from concomitant inflammatory bowel disease (IBD). Laboratory abnormalities consisted of mild elevation of transaminases and alkaline phosphatase, with marked elevation of immunoglobulin G in seven and detection of anti-nuclear antibodies in four of the eight children. In all cases, needle liver biopsy specimens revealed portal tracts considerably expanded by edema and chronic inflammation diagnostic of nonsuppurative cholangitis and nonsuppurative fibrosing pericholangitis. ERC showed decreased arborization in the whole biliary tree. In two patients, changes were confined to the intrahepatic portion of the biliary tract. No specific drug therapy was given to our patients. Those with concomitant IBD were treated with salazosulfapyridine (SASP). The clinical course has been mild in all patients up to now. It is concluded that PSC may be much more frequent in childhood than was considered before, especially in children with IBD.

Adolescent↗
PubMedDate not supplied

Treatment of an esophagorespiratory fistula by insertion of an esophageal Montgomery and tracheal dynamic stent after failure of conventional endoprosthesis.

Esophagorespiratory fistulae at the adult age can develop through malignant tumor growth, endoscopy, bougienage, laser therapy, or through a radiochemotherapy. We report a female patient with inoperable bronchial cancer, who developed a symptomatic esophagorespiratory fistula during radiochemotherapy with cisplatin. At first, conventional plastic tubes and then novel selfexpanding silicone-coated Gianturco-Song stents were used in an unsuccessful attempt to close the fistula. After the extraction of two Gianturco-Song stents, the insertion of a Montgomery-Salivary bypass stent in the esophagus and a dynamic stent in the trachea resulted in a permanent occlusion of the fistula. This case demonstrates that Montgomery-Salivary bypass stents do not tend to migrate due to their characteristic shape and self-fixation, and that the novel self-expanding, silicone coated Gianturco-Song stents can be extracted with rigid endoscopy if necessary.

Adult↗
PubMedDate not supplied

Oxyntomodulin: a cAMP-dependent stimulus of rat parietal cell function via the receptor for glucagon-like peptide-1 (7-36)NH2.

We have previously shown that in highly enriched rat gastric parietal cells the intestinal peptide hormones oxyntomodulin and glucagon-like peptide-2 (GLP-2) compete for receptor-binding with glucagon-like peptide-1 (GLP-1), a potent cAMP-dependent stimulus of H+ production in vitro. It is, however, unknown whether oxyntomodulin and GLP-2 elicit a biological response by interacting with the GLP-1 receptor. Therefore, we used enriched rat parietal cells to investigate the effects of both hormones on the production of cAMP and H+ ([14C]aminopyrine accumulation). Both parameters were stimulated by oxyntomodulin in a concentration-dependent manner. EC50 values were 6.2.10(-8) and 2.5.10(-7) M oxyntomodulin for stimulation of H+ and cAMP production, respectively. The maximally effective concentrations for stimulation of [14C]aminopyrine accumulation and cAMP production were 1.10(-6) and 1.10(-5) M oxyntomodulin, respectively. At these concentrations oxyntomodulin was nearly as effective as 10(-4) M histamine and equally effective as 10(-8) M GLP-1 (7-36)NH2. In the enriched parietal cell preparation there was no immunocytochemical evidence of contaminating D cells. Accordingly, the responses to oxyntomodulin and GLP-1 (7-36)NH2 were not augmented by incubating the cells in the presence of a polyclonal anti-somatostatin antibody. [14C]Aminopyrine accumulation in response to oxyntomodulin was inhibited by the GLP-1 (7-36)NH2 receptor antagonist, exendin (9-39)NH2, but not by the H2-receptor antagonist, ranitidine. Oxyntomodulin and carbachol acted additively to stimulate [14C]aminopyrine accumulation. GLP-2 (10(-7) to 10(-5)M) was without effect on basal H+ and cAMP production; however, at 10(-5) M GLP-2 markedly inhibited oxyntomodulin-stimulated [14C]aminopyrine accumulation. It is concluded that, by interacting with parietal cell receptors for GLP-1 (7-36)NH2, oxyntomodulin, but not GLP-2, directly stimulates H+ production by activating the adenylate cyclase.

Aminopyrine↗
PubMedDate not supplied

Reduced levels of coagulation factor XIII in patients with advanced tumor disease.

BACKGROUND/AIMS: Coagulation factor XIII, which induces the stabilization of fibrin the final step in the coagulation cascade, has various physiological effects. Among these, its beneficial effect in gastrointestinal bleeding episodes is well known. With the exception of inflammatory bowel disease, however, few data are available about this effect, particularly with regard to its role in diffuse bleeding in tumor patients. The study was designed to carry out prospective follow-up investigations, gathering data concerning factor XIII levels in patients with advanced gastrointestinal tumors and evaluating the course of the disease as well as the incidence of bleeding. METHODOLOGY: Sixty patients (22 women, 38 men; median age: 60; range: 29-79) with advanced gastrointestinal tumors were followed-up prospectively. Factor XIII levels were measured using chromogenic substrate. The correlation between the FXIII level and the patients' survival was analyzed using the Cox model. RESULTS: Factor XIII deficiency (below 70%) was seen in only 7 patients (11.6%), 6 of whom died within a median of 1.5 months after the measurement. In all patients however, there was a significant correlation (P = 0.0133) between FXIII levels and the risk of death. Four bleeding episodes occurred in 3 patients, three times with FXIII levels being below the lower normal range. When substitution was attempted, it was only successful in 1 patient in whom the FXIII level was reduced. CONCLUSIONS: FXIII may have predictive value as a marker for the prognosis in these patients with advanced tumor disease. Bleeding episodes were rarely seen, but when they do occur they may be associated with reduced levels of FXIII, and substitution may be beneficial as an adjunct or even as the sole therapeutic intervention.

Adult↗
PubMedDate not supplied

[Endoscopy in the diagnosis and treatment of acute obstructive pancreatitis].

Opie's theory that obstruction of the Ampulla of Vateri can be a significant factor in acute pancreatitis, is supported by various clinical observations. The significance of further pathogenetic factors such as anatomic variance of the duct systems, pressure differences, direction of flow and composition of secretions will have to be established in future studies. The ERCP plays an important role as a safe and sensitive diagnostic procedure. Therefore, ERC should be carried out in all suspected acute obstructive pancreatitis cases. The appropriate selection of patients employing clinical and laboratory criteria and other imaging procedures should, in the future, be defined more accurately. Presently, in proven ampullary obstruction we always perform immediate endoscopic therapy. However, the gallstone-induced obstructive pancreatitis usually has a good recovery course, even with conservative management. Therefore, clinical studies should prospectively direct us to those cases, in which the invasive endoscopic procedure should be limited, i.e. patients with expected serious courses. Diagnostic and therapeutic endoscopy does not increase the morbidity and mortality of the acute obstructive pancreatitis. Unlike the surgical approach, the endoscopic procedure is less invasive and is preferred by patients.

Acute Disease↗
PubMedDate not supplied

Endoscopic lithotripsy of bile duct stones using a new laser with automatic stone recognition.

Biliary stones can be removed in 85% to 90% of patients using endoscopic sphincterotomy; in the rest alternative methods are required. Thirty-eight consecutive patients in whom conventional methods had failed underwent laser lithotripsy with a new laser system. A flashlamp-pumped pulsed laser with rhodamine 6G as dye (594 nm) has a tissue-stone recognition system that can identify bile duct stones by analyzing backscattered light and interrupt the pulse in case of tissue contact (Lithognost, Telemit, Munich, Germany). Access of the 0.25- or 0.30-mm-diameter laser fiber to the stones was achieved perorally in 18 patients. In 13 of these cases, eccentrically located stones in the middle or proximal common bile duct were targeted with a 3.4-mm miniscope introduced through a standard duodenoscope. Fluoroscopically guided peroral lithotripsy was performed in 5 patients with stones in the distal common bile duct that could be approached with a standard ERCP catheter. Percutaneous cholangioscopic laser lithotripsy was carried out in 20 patients with stones not amenable to retrograde techniques. The mean number of bile duct stones per patient was 3.6, and the average diameter of the largest stone of each patient was 25 mm (range, 8 to 52 mm). The bile ducts were cleared in all but 1 patient in a mean number of 1.3 sessions lasting 15 to 115 minutes (mean, 60). No laser-related complications were observed. The Lithognost laser was successfully used in 37 of 38 patients referred for the removal of difficult bile duct stones.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMedDate not supplied

Long-term follow-up of endoscopic therapy in patients with post-surgical biliary leakage.

BACKGROUND/AIMS: Leakage is a rare complication of biliary surgery which is thought to follow a benign course after appropriate treatment. However there is a paucity of long-term follow-up data. PATIENTS AND METHODS: In this retrospective analysis, we present our experience with 21 patients in whom a biliary leakage was diagnosed following conventional and laparoscopic cholecystectomy (n = 14) or other types of biliary surgeries such as liver transplantation or segmental liver resection. Long-term follow-up (mean: 15.5 months) was obtained by telephone contact with patients, families or referring physicians. RESULTS: Endoscopic therapy was primarily successful in 20 of 21 patients and failed in 1 case with complete common bile duct dissection. Closure of the leakage was achieved by placement of nasobiliary tubes or endoprostheses with (n = 16) or without (n = 4) endoscopic papillotomy. Despite successful endoscopic therapy 3 patients died, 1 unrelated to the intervention, and 2 due to prolonged biliary sepsis (mortality: 9.5%; 30 day: 4.8%). Long-term follow-up in the surviving 18 patients showed them to be free of biliary complaints. CONCLUSION: ERCP is the primary modality to diagnose and treat post-operative biliary leakages. Despite rapid healing of the leakage in all 20 successfully treated cases, complications-related mortality was higher than previously suspected.

Adult↗
PubMedDate not supplied

Colonic bacterial activity determines the symptoms in people with fructose-malabsorption.

BACKGROUND/AIM: This study was performed to find a parameter to discriminate symptomatic from asymptomatic subjects with fructose-malabsorption. PATIENTS AND METHODS: Thirty-four subjects (12 m, 22 f; average age, 28.6 years; range 16-60) were investigated after an overnight fast. After intake of 25 g fructose, H2-tests were carried out. Endexspiratory breath samples were taken before the ingestion of the tested sugar and at 30 minute intervals over a 2 hour period. Hydrogen determination was performed immediately after sampling. Results were considered pathological if there was a rise in hydrogen over 20 ppm and a twofold increase from the initial value. Aerobic and anaerobic cultures from stool bacteria were set and incubated with 0.5 g fructose. RESULTS: Among 34 healthy controls, 13 malabsorbers (38%) were detected. Out of these malabsorbers, 6 (46%) reported gastrointestinal concomitant symptoms. Symptomatic and asymptomatic subjects with fructose-malabsorption showed a comparable increase in hydrogen levels. The disappearance rate of fructose in the stool cultures was significantly elevated in the symptomatic group compared with the asymptomatic, but only in the anaerobic culture. CONCLUSION: This activity of colonic bacteria, significantly discriminating symptomatic subjects with fructose-malabsorption from asymptomatic, enhances the importance of fructose-malabsorption in the differential diagnosis of people with non-specific abdominal complaints. Antibiotic therapy in severe cases should be considered a therapeutical approach. Moreover these results may support the role of nutritional carbohydrates in the pathogenesis of colonic diseases.

Adult↗