Biomedical subjects

W Leitner

Publications and source records attributed to W Leitner.

24 records · Page 2Linked to original sources

PubMed1992

[Autotransplantation of the spleen in rats: development, function and cytokine expression in intra-omental and subcutaneous regeneration].

The implantation of splenic tissue at different implantation sites (intraomental and subcutaneous) into one animal (Lewis rats) results in the development of splenic nodules at both sites. In a quantitative immunohistological analysis of splenic compartments such as red pulp (RP), periarteriolar lymphoid sheaths (PALS), marginal zone (MZ) and follicles (F) the T-cell reduction was related to the T(helper) cells in the MZ and T(supp/cyt) cells in the PALS. In contrast, the cell density of B cells and ED-1+ macrophages in the PALS and T(supp/cyt) cells in the MZ was increased. Significant differences between the implantation sites were restricted to CD5+ cells (thymocytes and T cells) in the MZ and OX-33+ cells (B cells with LCAB antigen) in the PALS. The reorganisation of the compartments of subcutaneous implants showed a delay of one week as compared with omental ones. Functional assays like haemolytic plaque assay, mitogen stimulation and mixed lymphocyte assay elicited an analogous delay of the functional maturation of IgM-positive B cells, a reduced proliferation of both transplant groups after pokeweed mitogen (PWM) stimulation, a decreased response after lipopolysaccharide (LPS) stimulation in solely subcutaneous replants and no differences concerning the mitogens concanavalin A (ConA) and phytohaemagglutinin (PHA). Both transplant groups showed a significantly reduced allogeneic response. The results of the functional analysis and the abnormal mRNA expression of Il-5, Il-6 (Interleukin 5 and 6), GMCSF (Granulocyte-Macrophage-Colony-Stimulation-Factor) and IFN-gamma (Interferon gamma) in subcutaneous replants indicate subtle molecular alterations (independent of a spleen-like immunoarchitecture) at this site.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1991

Gene expression of type I phospholipase A2 in pancreatic beta cells. Regulation of mRNA levels by starvation or glucose excess.

Messenger RNA from intact rat pancreatic islets, or from transformed hamster beta (HIT) cells, hybridized with the cDNA probe for type I (but not type II) phospholipase A2. The levels of phospholipase A2 mRNA increased in islets from fasted rats; they decreased in islets cultured in a high glucose concentration (control values at 5.5 mM glucose = 150 +/- 6% of those at 22 mM) which impaired subsequent insulin secretion (reduction in second-phase release = 70 +/- 11%). These studies uniquely demonstrate that type I phospholipase A2 is expressed specifically in beta cells and that nutrient availability modulates transcript levels, an effect which could that nutrient availability modulates transcript levels, an effect which could contribute to the detrimental influence of prolonged hyperglycemia on islet function.

Animals↗

PubMed1981

Influence of an antiarrhythmic premedication on the development of premature ventricular contractions during fiberoptic gastroduodenoscopy.

Heart rate, blood pressure and ECG changes during fiberoptic gastroscopy were examined in 128 patients, 60 of whom had been orally premedicated with Mexiletine. 55% of the non-premedicated patients developed occasional, and 22% of this group developed accumulated or frequent, premature ventricular contractions. In the patient group with antiarrhythmic premedication, the respective figures were 25% and 8%, and in this group patients with a normal ECG developed premature ventricular contractions less frequently than patients with pathological changes in the ST segment. The antiarrhythmic premedication had no influence on pulse or blood pressure.

Arrhythmias, Cardiac↗

PubMed1980

[Social profile and accompanying diseases in acute and chronic pancreatitis (author's transl)].

200 patients with pancreatitis were examined for various concomitant and previous diseases, and socioeconomic factors, in a retrospective study. This pancreatitis group (PG) was compared with a control group (CG) of 250 patients. Most frequent amongst the etiological factors, were biliary diseases, especially a state after cholecystectomy. Second in rank, was chronic alcoholism. For women, the incidence was highest in the 7th decade; for men, there was a double peak in the 4th and 6th decade, respectively. The incidence was about equal for both sexes. The following factors were found to play no essential role in the PG: type of profession, cigarette consumption, gastric and/or duodenal ulcers, partial gastric resection, renal and cardiac insufficiency, viral hepatitis, liver cirrhosis of hypertriglyceridemia. There is a significant accumulation of mumps in the history of the PG, which had gone along without any clinically detectable affection of the pancreas in childhood, in practically all cases.

Acute Disease↗

PubMed1979

[The influence of a beta-adrenolytic premedication on cardiovascular parameters and plasma free fatty acids during esophago-gastro-duodenoscopy (author's transl)].

Three groups of patients with different premedications were examined for changes of blood pressure, heart rate, ECG and plasma free fatty acid levels during esophago-gastro-duodenoscopy: Group A was premedicated with Bunitrolol, group B was premedicated with Hyoscin-N-butyl-bromide and diazepam, group C was endoscopied without premedication. The pulse rate rose significantly less in group A than in groups A and C; the same phenomenon was observed with regard to the systolic blood pressure. Premature beats occurred in all 3 groups: 32 per cent of the patients in group A, 43 per cent in group B and 60 per cent in group C had at least occasional premature beats; an accumulation of premature beats however occurred significantly less frequently in group A than in groups B or C. A drop of the ST-part of the ECG occurred with about the same frequency in each group. An increase of the plasma free fatty acids, which was noted in groups B and C, could be observed in Group A. A pre-endoscopic medication of beta blocking agents could be a useful measure in patients with labile arterial hypertension, vegatative dysregulation and a hyperkinetic heart syndrome.

Adrenergic beta-Antagonists↗

PubMed1979

[Early diagnosis of cancer of colorectal carcinoma by rectosigmoidoscopy (author's transl)].

The colorectal cancers in greater part grow out of polyps, which can be looked upon as optional precancerosis. Own results together with literature-reports show a distinct increase of the frequency of polyps beyond the age of fortyfive. The only digital palpation of the rectum is insufficient; it leads to the diagnosis of a rectum polyp only in 15.5%, to the diagnosis of a cancer in 13% of cases. With the rectosigmoidoscopy however the diagnosis is successful in 70% of cases. The percentage of precancerous polypous alterations detected by rectosigmoidoscopy is approximately the same in medical check-up as in directed examinations of patients with anorectal discomfort. A restriction of rectosigmoidoscopy to the last-named group of persons is not any longer justified. The polypectomy in the rectum is a real cancer-prevention.

Adenocarcinoma↗