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Biomedical subjects

R Schmidt

Publications and source records attributed to R Schmidt.

At least 721 records · Page 40Linked to original sources
PubMed1980

[Clinical trial in couples of effectiveness and side-effects of gold and D-penicillamine in long term treatment of rheumatoid arthritis (author's transl)].

A prospective clinical trial in couples was done to compare effectiveness and toxicity of gold and D-penicillamine (D-Pen.) in treatment of rheumatoid arthritis (r.A.). Respecting defined criteria 70 patients were put to couples according to a random list and were treated with gold or D-Pen. alternatively. Physical and laboratory indices of inflammatory activity were checked every 3 months, X-rays every 12 months. Dropouts (side effects, missing compliance, uneffectiveness) were replaced by the nextcoming fitting patient. Thirty-two of 147 totally recruited patients stopped treatment because of side effects, three because of unsatisfying efficiency. Forty-two patients shuned the necessary controls. The clinical course was better in 16 couples with gold, only in sex couples with D-Pen. Thirteen pairs showed no difference in this respect (p = 0.05). Looking to the laboratory parameters separately D-Pen. tends to be superior (p < 0.05), radiografic deterioration seems to be more seldom with gold (< 0.05). Side effects occur with both drugs in comparable frequency (15/44 with D-Pen., 17/52 with gold), but the complications with D-Pen. are more serious. Altogether this trial shows gold superior to D-Pen. in the long-term treatment of r.A.

Adult↗
PubMed1980

[Technic and indication for controlled ultrafiltration].

The isolated ultrafiltration with commercial dialysators gives a possibility of the massive dehydration in a short time without disturbing the well-being of the patient. If in patients undergoing a dialysis a following haemodialysis (sequential ultrafiltration haemodialysis) is necessary, particularly in patients with acute complications hypotonic circulatory conditions may develop. An infusion of a fourfold concentrated human dry plasma during the ultrafiltration may prevent these hypotensions, since reduction of osmolality and losses of circulation-effective substances are prevented during haemodialysis. With the help of this kind of treatment conditions of hyperhydration of different genesis may be removed also in patients with inclination to hypotension.

Acute Kidney Injury↗
PubMed1980

[Experimental studies of the treatment of hypotensive blood circulation disorders during sequential ultrafiltration hemodialysis].

Particularly in risk patients who in the condition of hyperhydration underwent sequential ultrafiltrations-haemodialysis treatment the decrease of blood pressure which appears in individual cases under the treatment is negatively decisive for the success in therapy. In 33 hyperhydrated patients who underwent dialysis, therefore, with the help of the fourfold concentrated human dry plasma DAB 7 the influence of a combined osmo- and substitution therapy on this circulatory complication was investigated. Under the sequential ultrafiltration by means of application of human dry plasma also at an initial decrease of blood pressure not only a stabilisation, but also an increase of blood pressure is achieved. This favourable circulatory behaviour continues also during the following haemodialysis, Apparently by the application of the human dry plasma physiological compensation mechanisms are evoked by various factors such as pharmacological effects on the excitable structures by sodium, potassium and catecholamines and physical effects on the plasma volume by increase of the osmolality and increase of the oncotic pressure. The use of human dry plasma allows the performance of an ultrafiltration treatment as well as of a haemodialysis in hyperhydrated risk patients who are in a circulatory collapse and thus considerably enlarges the area of indication of the sequential ultrafiltration dialysis treatment.

Adult↗
PubMed1980

Mitochondrial release of Ca2+ during sustained nerve activity in the electric organ of Torpedo marmorata.

The calcium content of mitochondria isolated from the Torpedo electric organ was determined by atomic absorption spectroscopy. The mitochondrial fraction was found to contain 830 ng-atom Ca/mg protein. For comparison a fraction of isolated nerve endings contained 250 ng-atom Ca/mg protein. When tissue was continuously stimulated at a frequency of 5 Hz via the electromotor nerves, the Ca content of the mitochondrial fraction which is likely to contain both pre- and postsynaptic mitochondria was reduced proportionally to the decrease in transmitter content of the isolated nerve terminal fraction. After 5,000 pulses, the mitochondrial fraction had lost 80% of its Ca contents. When tissue was stimulated after previous perfusion with d-tubocurarine and blockade of electrical response the same number of pulses caused only a loss of 20--40% in the Ca content of the mitochondrial fraction. Release of transmitter was not affected by d-tubocurarine. The results suggest that repetitive stimulation in the absence of postsynaptic receptor blockade causes loss of Ca from both nerve terminal mitochondria and mitochondria of the myotube-derived electrocytes. In the presence of d-tubocurarine Ca is lost from presynaptic mitochondria only.

Acetylcholine↗
PubMed1980

Preferential calcium staining of mitochondria in stimulated cholinergic nerve endings.

The fine structure of the Torpedo electric organ was investigated during different functional states using fixation media with elevated calcium concentrations. When electric tissue was stimulated (5,000 pulses, 5 Hz) and subsequently fixed in an s-collidine buffered aldehyde fixative containing 5 mM CaCl2 mitochondria in both nerve terminals and postsynaptic electroplaque cells showed electron-dense deposits. When tissue blocks were stimulated in the presence of d-tubocurarine (250 microM) which blocked electrical response deposits were restricted to presynaptic mitochondria. Electron-dense deposits were never observed in unstimulated tissue. The observations suggest that after stimulation mitochondria have an increased calcium binding capacity. In conjunction with previous biochemical findings (Schmidt and Zimmermann, 1980), we suggest that this increased binding capacity is due to a previous stimulation induced loss of calcium from activated mitochondria.

Animals↗
PubMed1980

Plasminogen activator induction and platelet aggregation by phorbol and some of its derivatives: correlation with skin irritancy and tumor-promoting activity.

Phorbol and eight of its derivatives were investigated for their ability to stimulate the synthesis of the enzyme plasminogen activator in cultured chick embryo fibroblasts and to aggregate human blood platelets and have been assayed for tumor, promoting and skin, irritant activities. Over a range of concentrations, elevation in the levels of plasminogen activator activity induced by phorbol derivatives correlates well with their promoting and irritant properties. In the platelet aggregation assay however, the parallelism between the activities measured in different biological assays was less complete. While strong promoters, such as TPA, are potent aggregating agents, and weak promoters, such as PDA, are poor or ineffective inducers of aggregation, two derivatives, PDD and PDB, deviate from this general result. Platelets must be exposed to PDD in relatively high concentrations before they will aggregate, and PDB was found to be the most potent aggregating agent of all the derivatives tested.

Animals↗
PubMed1980

Isolation of protoplasts and vacuoles from storage tissue of red beet.

A fast and efficient method is described for the isolation of protoplasts and vacuoles from storage tissue of Beta vulgaris L. The viability of the isolated protoplasts is indicated by the development within a few hours of plasma strands with active cyclosis as well as by transport activity.The effect of aging of the tissue on the yield and on the properties of the protoplasts is examined. Adding 1 millimolar dithiothreitol to the water during the aging of the tissue prevents a change of the cell wall structure which otherwise reduces the protoplast yield within 2 days to zero. When protoplasts are isolated from tissue after different times of aging, they show an increase in transport activity which parallels that in the intact tissue.

Journal Article↗
PubMed1980

Hypercholesterolaemia and hypertriglyceridaemia in patients with analgesic nephropathy.

Patients with analgesic nephropathy are reported to have a higher risk of atherosclerosis. One possible reason for this is a high incidence of hyperlipaemia in patients with analgesic nephropathy. In a retrospective study, serum cholesterol and serum triglyceride concentrations of patients with analgesic nephropathy and moderately restricted renal function were significantly higher compared to a control group with other renal diseases of similar age and degree of renal insufficiency. Hyperlipaemia in analgesic nephropathy is not explained by end-stage renal failure on one side or protein loss as in nephrotic syndrome on the other side. Some possible mechanisms for hyperlipaemia in analgesic nephropathy are discussed.

Adult↗
PubMed1980

[Polyps of the sigmoid and rectum following ureterosigmoidostomy].

Implantation of the ureters in the sigma is practicable as far as cystectomy or congential malformations are concerned. The problem of the development of sigma-rectum polyps following ureterosigmoidostomy (uss) is being discussed within the description of three own case reports. The polyp of our first case is classified as an adenomatous polyp with marked retention of mucus. The polyp of our second case is regarded as a polypoid hamartia caused by the operation. The polypoid lesion of our third case must be regarded as a heterotopia of the urinary tract in connection with the known malformation of the urogenital tract of this patient. Patients who had undergone uss have an increased risk for the development of rectal carcinoma. But on the other hand the polypoid lesions following use must not necessarily be predecessors of carcinomas! In rather seems that the polyps following uss are very heterogenous. Only the first case being described in the present report may be regarded as a potential predecessor of a carcinoma. A tabulated review of the literature of the described polyps after uss is given. Etiological aspects are being discussed.

Adolescent↗
PubMed1980

[Possibilities for automatic quantitative image analysis of cell organelles stained ultrahistochemically].

Metal-containing secretory granules of alpha 2-cells of the Langerhans' islets of normal and alloxandiabetic rats were stained for electron microscopy by a special method. Thereafter the electron micrographs were analysed by the Quantimet 720 image analysing computer with respect to size of the granules and their quantitative distribution in classes. The following statistical tests verified significant differences between the distributions of the granules under normal and diabetic conditions. The secretory granules from alloxandiabetic animals were diminished distinctly. The examination by image analysing computer confirmed objectively observations, we have made and published formerly.

Animals↗
PubMed1980

[Hemodialysis with Bi-Flo cannulas].

It is reported on the use of the double-lumen Bi-Flo-puncture canule in chronic haemodialysis patients. In a sufficient flow through the atrioventricular fistula no significant decrease of the effect of dialysis was the result. It is recommended to render the proof of a perhaps existing shunt volume between the two lumina of the Bi-Flo-canule before the permanent use of it, in case of the existence of an only moderately functioning atrioventricular fistula.

Arteriovenous Shunt, Surgical↗