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Felix Rockmann

Publications and source records attributed to Felix Rockmann.

5 recordsLinked to original sources

Glucagon production of the rat insulinoma cell line INS-1-A quantitative comparison with primary rat pancreatic islets.

The rat insulinoma cell line INS-1 is the most commonly used clonal cell model in pancreatic beta-cell research. Considering the multihormonality of many insulinomas we examined as to how INS-1 cells comply with the notion of resembling a pure beta-cell line. Glucagon immunoassays revealed that INS-1 cells secrete glucagon in a similar range as islets. By immunohistochemistry we detected a cytoplasmic glucagon signal in INS-1 cells which colocalized with C-peptide. Cellular content of preproglucagon-mRNA and glucagon protein in INS-1 cells was less than two percent of the respective values in islets, which probably reflects differences in the intracellular metabolism and/or secretory pathways. Taken together, it is obvious that INS-1 cells do not represent an exclusively insulin producing beta-cell line.

Animals↗

Microsatellite analysis of pleural supernatants could increase sensitivity of pleural fluid cytology.

Pleural effusions may result from various inflammatory, hemodynamic, or neoplastic conditions. A common diagnostic problem lies in distinguishing malignant from benign pleural effusions using routine cytological evaluation. We studied pleural fluid samples obtained from 14 patients with histologically confirmed malignancy and from 6 patients with benign pleural effusions using 12 microsatellite markers from 8 different chromosomal regions. Supernatants and cellular sediments of all 20 pleural fluid samples were analyzed. Routine cytological examination was 100% specific for malignancy but was only 57% sensitive. Microsatellite analyses of pleural fluid supernatants showed genetic alterations in tumor patients only. However, 50% of pleural effusions that were considered negative for malignancy by routine cytological analysis showed either loss of heterozygosity or microsatellite instability. The sensitivity of pleural fluid examination rose to 79% when routine cytological assessment was supplemented by molecular studies. Our data suggest that microsatellite analysis increases the sensitivity of cytological pleural fluid examination in assessing potential malignancy and that combining cytological and molecular methods may improve yield and certainty in diagnostically challenging cases.

Aged↗

Association of Crohn's disease and latent celiac disease: a case report and review of the literature.

BACKGROUND: Crohn's disease is a chronic inflammatory disease of the intestine potentially affecting all parts of the intestine with predilection sites in the terminal ileum and proximal colon. Its prevalence in Western Europe is 20-40/100,000 with equal affection of both sexes and familiar accumulation. Histopathologically, it is characterized by a discontinuous, segmental manifestation and implication of all intestinal layers. Celiac disease, on the other hand, is defined by histologically proven villous atrophy associated with hyperplasia of crypts, lymphocytic infiltration and clinical improvement after a gluten-free diet. CASE REPORT: We report the case of a 52-year-old man presenting with long-term diarrhea and loss of weight associated with Crohn's disease. After interventional therapy for an unstable coronary artery syndrome and medical therapy for hyperthyroidism, the diarrhea stopped only after maintaining a gluten-free diet. A latent form of celiac disease (clinical symptoms, improvement after gluten-free diet, detection of anti-gliadin IgA antibodies, negative histology) was diagnosed. CONCLUSION: To our knowledge, this is the first report on the association of Crohn's disease and the latent form of celiac disease in the same patient. Whereas in most cases, Crohn's disease develops secondary to a pre-existing celiac disease, in our patient, latent celiac disease was diagnosed years after the onset of and therapy for Crohn's disease.

Celiac Disease↗