Search PubMed⌕ Search

Biomedical subjects

W Schmidt

Publications and source records attributed to W Schmidt.

At least 721 records · Page 40Linked to original sources

Orthotopic and heterotopic autotransplantation of the rat kidney.

End-to-end anastomosis of the kidney vessels and ureter can easily be done without suture. Artery and ureter are connected via an intraluminal silicone tube, anastomosis of the vein is performed with a cuff-technique. In case of orthotopic transplantation the left kidney is transplanted to the right side after right nephrectomy. Furthermore heterotopic transplantation was tried: kidney vessels were either connected with jugular or femoral vessels. In contrast to orthotopic transplantation higher thrombosis rate was observed, probably due to varying sizes of donor and recipient vessels. Our method of orthotopic autotransplantation is easier, less time consuming and has a lower complication rate than homologous kidney transplantation with suture techniques.

Animals↗

[Investigations in the streaming blood of the alert animal and man. III. Postprandial and therapeutically induced changes of electrolyte concentration and hematocrit in man during hemodialysis (author's transl)].

Arterial haematocrit and blood electrolyte concentrations are measured continuously by conductometry in three hemodialysis patients. Haematocrit elevation during meals, particularly when rich in carbohydrates, indicate fluid losses into the gut. Simultaneous biphasic responses in electrolyte concentration indicate osmotic and diffusional shifts of water and electrolytes. Similarly, blood volume and electrolyte concentration changes can be followed during and after intravenous infusion of colloid and crystalloid solutions. The quantitative aspects of such measurements are discussed.

Adult↗

Preparation of colony stimulating activity from large batches of human urine and production of antisera against it.

In vitro induction of myelopoetic colonies from mouse bone marrow has been used for measurement of leucopoetic colony stimulating activity (CSA) isolated from large batches of human urine. After high flow dialysis in artificial kidneys and immediate adsorption to DEAE-Cellulose, followed by purification on Con A-Sepharose, treatment with insoluble Papain and gelfiltration on Sephadex G 100, enrichment of CSA was about 6,000-fold. An important step of the enrichment procedure was the separation from a CSA-inhibiting protein, probably combining with CSA. Specific activity was further increased by preparative polyacrylamide gel electrophoresis to 5.3 X 10(6) units per mg protein. The total enrichment exceeded 25,000-fold. The final purification product consisted of a group of closely related proteins with high specific activity. Antisera raised with one of the electrophoretic fractions suppressed bioactivity in each of the different purification steps including the final CSA fractions differing in electrophoretic mobility. The antisera furthermore inhibited CSA in human lung and monocyte conditioned media but had only very little effect on partially purified CSA from stimulated human lymphocytes as well as CSA derived from mouse lung conditioned medium.

Chromatography, Gel↗

Alterations in calcium levels of coronary sinus blood during coronary arteriography in the dog.

Intracoronary administration of contrast materials causes myocardial depression which is related to serveral physiochemical properties of the contrast solution. The role of variations in ambient calcium ions (Ca++) in mediating this effect was evaluated in 19 anesthetized dogs. Sodium meglumine diatrizoate caused decreases in left ventricular peak systolic pressure (LVPSP),-12.6 +/- 3.2%, and dp/dt at a left ventricular pressure (LVP) of 40 mm Hg, -14.3 +/- 4.1%. The total calcium (Cat) decreased from 10.2 +/- 0.2 to 6.5 +/- 0.2 mg%, while Ca++ decreased from 4.6 +/- 0.1 mg% to 2.3 +/- 0.7 mg%. In the presence of systemic hypocalcemia the myocardial depressant actions of this contrast materials were accentuated. Intracoronary administration of contrast material with added Ca++, calcium sodium meglumine metrizoate, caused no myocardial depression. Total calcium decreased only slightly (10.2 +/- 0.2 to 9.1 +/- 0.2 mg%), while Ca++ increased (4.8 +/- 0.1 to 5.1 +/- 0.2 mg%. During systemic hypocalcemia, the calcium metrizoate compound induced increases in LVPSP and dp/dt/LBP40. Thus, contrast materials caused myocardial depression which, at least in part, was related to reduction of ambient calcium through a dilutional and binding action. The addition of Ca++ to monomeric contrast materials reversed the myocardial depressant action and produced a transient rise in ambient Ca++.

Animals↗

Degradation products of fibrinogen by elastase-like neutral protease from human granulocytes. Characterization and effects on blood coagulation in vitro.

We investigated the effect of elastase-like neutral protease isolated from human granolocytes on human fibrinogen. Dependent on enzyme concentration and time of incubation, the elastase-like protease induced a progressive degradation of fibrinogen. Analysis of the remaining polypeptide chains showed a high susceptibility of the Aalpha- and low susceptibility of the gamma-chain of fibrinogen towards the proteolytic action of the enzyme. The split products were characterized by polyacrylamide gel electrophoresis and two-dimensional immunoelectrophoresis. They showed antigenic determinants of fibrinogen and of plasmin-induced proteolysis products D and E. The cleavage fragments isolated by gel chromatography had distinct molecular weights. Coagulability of fibrinogen by thrombin was inhibited according to the concentration of the protease and the time of incubation. Split products of fibrinogen with higher molecular weight prolonged the coagulation time of native fibrinogen, whereas low molecular weight fragments were ineffective.

Blood Coagulation↗

[The determination of the oncolytic effect of clostridia with the hamster amelanotic Melanoma no.3--a quantitative study utilizing defined criteria of evaluation (author's transl)].

With a view of satisfying the practical demands on a diagnostic tumour clostridium assay the development of a biological tumour test model is of prime importance. We are interested in a safe method for differentiating between oncolytic clostridia and clostridial strains exerting no oncolytic capacity. It was therefore attempted to develop a reproducible assay system using hamster A-Mel-3 as a reference tumour. This was finally attained by quantifying oncolysis taking into account the criterium of spontaneous onconecrosis of this tumour. The proposed oncolytic assay system was submitted to a mathematical regression analysis using different strains of clostridia as well as different batches of cultivated spores of one and the same strain. The results are critically compared with the current literature.

Animals↗

[Cardio-pulmonary parameters after myocardial infarction in the late period of recovery. Investigation at rest and during exercise (author's transl)].

From 22 patients in the late period of recovery from myocardial infarction, cardio-pulmonary data were recorded at rest and during exercise. The physical work was increased stepwise until patients reached their individual limit of exercise. According to the different work capacity four groups of patients were formed with the aim to demonstrate the adaption processes of cardio-pulmonary parameters until reaching the peak of work capacity. In one half of the patients we still found signs of cardial insufficiency at rest. After only slight physical work signs of cardiac insufficiency appeared also in the other half of patients.

Female↗