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Biomedical subjects

T Schmidt

Publications and source records attributed to T Schmidt.

At least 271 records · Page 15Linked to original sources
PubMed1990

Influence of long-term treatment with ketanserin on blood pressure, pulmonary artery pressure, and cardiac output in patients with heart failure.

Ketanserin is a selective serotonin2-receptor blocker and by this mechanism decreases peripheral resistance and blood pressure in hypertensives. We examined the hemodynamic effects of ketanserin during long-term treatment in patients with heart failure. Five male patients with coronary artery disease and heart failure (NYHA classes II-III) were treated with ketanserin (80 mg daily) for 12 months. Before treatment, after 4 weeks, and after 12 months treatment, a Swan-Ganz catheter was placed into the pulmonary artery and pulmonary wedge pressure, cardiac output, mean arterial pressure, and heart rate were measured at rest and on exertion. The pulmonary wedge pressure at rest decreased from 8 mmHg before to 6 mmHg after 4 weeks and 12 months treatment; on exertion, it decreased from 31 mmHg before treatment to 24 mmHg after 4 weeks treatment and to 21 mmHg after 12 months treatment. The mean arterial pressure also decreased at rest and on exertion after 4 weeks treatment as well as after 12 months treatment. Cardiac output increased slightly and heart rate was unaltered. No serious side effects occurred. Ketanserin could become an alternative vasodilator drug in the treatment of patients with heart failure.

Aged↗
PubMed1990

Influence of carvedilol and propranolol on coronary blood flow.

A total of 17 patients with angiographically proven coronary artery disease and at least one stenosis blocking greater than or equal to 70% of the left anterior descending or circumflex artery were included in a double-blind, randomized study. They received either 5 mg carvedilol or 6 mg propranolol intravenously. Heart rate, aortic pressure, mean coronary sinus pressure and coronary flow (thermodilution) were measured and coronary resistance and the rate-pressure product were calculated before and 25 min after injection. Carvedilol significantly (P less than 0.05) lowered the heart rate (mean, 76 to 69 beats/min), aortic pressure (mean, 153/80-135/72 mm Hg), rate-pressure product (mean, 117-93 mm Hg/min), and coronary flow (mean, 114-94 ml/min). Coronary resistance (mean, 0.97-1.07 mm Hg x min/ml) and coronary flow related to the rate-pressure product (mean, 1.0-1.02 ml/mm Hg) showed no significant change after carvedilol treatment. Propranolol lowered the heart rate (mean, 76-64/min; P less than 0.05) and rate-pressure product (mean, 109-96 mm Hg/min; not significant). Aortic pressure (mean, 145/72-147/74 mm Hg), coronary flow (mean 109-101 ml/min), coronary resistance (mean, 1.1-1.2 mm Hg x min/ml), and coronary flow related to the rate-pressure product (mean, 1.12-1.19 ml/mm Hg) showed no significant change after propranolol administration. Following single application, carvedilol lowered the rate-pressure product more markedly than did propranolol on account of its acute blood-pressure-lowering effect. No differences in the hemodynamic effects of carvedilol and propranolol were found. Neither drug seems to influence the adaption of coronary flow to myocardial oxygen demand.

Adrenergic beta-Antagonists↗
PubMed1990

[A questionable parasitic macular cyst].

A 60 year old male patient is introduced who developed a loss of vision caused by chorioretinal cystic alteration in the macula of the left eye 9 months after a routine extracapsular cataract surgery with implantation of posterior chamber lens. There existed no other general symptoms, hematologic values and serology were regular. Having discussed literature the diagnosis of solitary Toxocara canis granuloma was produced.

Cysts↗
PubMed1990

In vitro investigation of BK-218, a new oral and parenteral cephalosporin.

The antibacterial activity of BK-218 was similar to that of cefamandole when it was tested against several laboratory strains. The inhibiting effect of BK-218 was greater than that of cephalexin and cefoxitin on penicillin-binding proteins of Escherichia coli HB101. This result was in close correlation with the relative inhibition of radiolabeled glucosamine incorporation (greatest with BK-218) and with the lytic effect (most intensive with BK-218). BK-218 proved to be a good inhibitor for all five of the beta-lactamases that were investigated, although two enzymes (Enterobacter cloacae P99 and Pseudomonas aeruginosa Cilote) hydrolyzed it to some extent.

Bacteria↗
PubMed1990

Hemodynamic effects of nebivolol at rest and on exertion in patients with heart failure.

Nebivolol is a novel B-1-adrenoceptor-blocking drug with an unusual hemodynamic profile unlike classical B-blockers. In dogs and in healthy volunteers it decreases blood pressure and heart rate but improves left ventricular function. The authors studied 10 male patients with coronary artery disease and heart failure (ejection fraction mean = 46%). A Swan-Ganz catheter was placed into the pulmonary artery, and the mean blood pressure, the heart rate, the pulmonary artery pressure, the pulmonary wedge pressure, the right atrial pressure, the cardiac output, and the stroke volume were measured at rest and on exertion before and after seven days' treatment with oral nebivolol (5 mg/day). While the blood pressure and the heart rate decreased significantly, the pulmonary artery and wedge pressures, as well as the right atrial pressure and the cardiac output, did not change during treatment. The stroke volume increased significantly. The maintained cardiac output cannot be explained by any changes in preload or afterload; instead a positive inotropic mechanism must be assumed. Unlike other B-blockers it seems to be possible to treat patients with heart failure with nebivolol without causing the hemodynamic situation to deteriorate.

Adrenergic beta-Antagonists↗
PubMed1990

A mycoplasmal protein influences tumour cell invasiveness and contact inhibition in vitro.

Fab fragments of a monoclonal antibody directed against p37, a protein associated with the surface of FS9 mouse sarcoma cells, were previously found to inhibit the highly invasive behaviour of FS9 cells in vitro. We show that p37 originates from Mycoplasma hyorhinis. Infecting various cell lines with the mycoplasma consistently increased their invasiveness when confronted with chicken heart fibroblasts using Abercrombie's confronted explant technique. Conversely, removing the mycoplasmas or blocking p37 with specific Fab fragments reduced invasiveness. Analysis of individual cell collisions using time-lapse filming showed that the addition of Fab fragments to cells infected with M. hyorhinis greatly increased the level of contact inhibition. The antibody also reduced the invasiveness of transformed cells that did not express the p37 antigen. Hence, a cellular protein or proteins that are structurally related to p37 apparently influence invasive behavior.

Animals↗
PubMed1990

[Analytical dye studies on the polarization microscopic detection of collagen with Solaminrot 4B. I].

It is known that the birefringency of the collagen fibres is selectively enhanced by staining with Sirius Red. According to experiences, the most authors usually take Sirius Red F3BA as dye. We use the disazo dyestuff Solaminrot 4B produced by VEB Chemiekombinat Bitterfeld. Thus, the present paper is dealing with physicochemical analysis of the dye. We investigated 2 charges of the Solaminrot 4B. The 1st charge contain supplementary substances; the 2nd charge is without ones. It is reported a series of data resulting from chromatographic and spectroscopic investigations.

Azo Compounds↗
PubMed1990

Prevention of an early re-occlusion after thrombolytic therapy of acute myocardial infarction by ketanserin.

A problem after successful thrombolytic therapy of acute myocardial infarction is the early occurrence of re-occlusions. An incidence between 10 and 30% is reported. All efforts made so far to reduce the re-occlusion rate using a variety of agents have been disappointing. In a pilot study 20 patients with acute myocardial infarction were treated, in whom a successful lytic therapy with urokinase or rt-PA was documented by means of coronary angiography 90 min after the beginning of treatment. Subsequently the patients were heparinised (thrombin time greater than 30 s), and in addition the selective serotonin-2 receptor-blocking agent ketanserin was given intravenously (4 mg/h). After 24 h the occurrence of early reocclusions was investigated by control angiography. None of the 20 patients showed reocclusions. The degree of stenosis in the infarcted vessel was 72% immediately after lytic therapy, and 68% after 24 h. These preliminary results may suggest a possible reduction in the re-occlusion rate after thrombolytic therapy with a combination of heparin and ketanserin.

Adult↗
PubMed1989

High-performance liquid chromatographic determination of some polar phospholipids in serum.

The experimental conditions have been optimized for high-performance liquid chromatographic determination of phosphatidylethanolamine (PE), phosphatidylcholine (PC) and sphingomyelin (SM) in serum. The phospholipids are separated on a silica gel column, using a mobile phase of acetonitrile-methanol-water (100:10:18, v/v), with ultraviolet photometric detection at 200 nm. The limit of detection was 0.2 micrograms (in 20 microliters) for natural phospholipids and 2.5 micrograms for synthetic phospholipids; the relative standard deviation was ca. 5%. An alternative detection is tensammetry at a mercury electrode, at a potential of -1.8 V, with an a.c. current frequency of 60 Hz and an amplitude of 20 mV. The tensammetric detection has an advantage in its independence of the structure of the phospholipids. In measurements without a column (flow-injection analysis), the tensammetric detection also yields a somewhat lower limit of detection than photometry (0.15 micrograms per 20 microliters), but this value increases more than ten times in chromatographic detection. The precision is poorer and is more susceptible to interferences. The method was applied to the determination of the above substances in the blood of obese children, as a function of physical stress and spa treatment. It was shown that physical exercise causes a decrease in the contents of PE and PC in the patients. On the other hand, the spa treatment has no pronounced effect on the phospholipid content in the blood.

Adolescent↗
PubMed1989

Protein-RNA interactions in an icosahedral virus at 3.0 A resolution.

Nearly 20 percent of the packaged RNA in bean-pod mottle virus (BPMV) binds to the capsid interior in a symmetric fashion and is clearly visible in the electron density map. The RNA displaying icosahedral symmetry is single-stranded with well-defined polarity and stereochemical properties. Interactions with protein are dominated by nonbonding forces with few specific contacts. The tertiary and quaternary structures of the BPMV capsid proteins are similar to those observed in animal picornaviruses, supporting the close relation between plant comoviruses and animal picornaviruses established by previous biological studies.

Amino Acid Sequence↗
PubMed1989

Signal transmission in exocrine cells is associated with rapid activity changes of acyltransferases and diacylglycerol kinase due to reversible protein phosphorylation.

Stimulation of secretion in guinea pig parotid gland lobules by either isoproterenol or carbachol is associated with a removal of acyl groups from the acyl-CoA pool and their incorporation into diacylglycerols and triglycerides (Söling, H. D., Machado-De Domenech, E., Kleineke, J., and Fest, W. (1987) J. Biol. Chem. 262, 16786-16792). This is associated with an increased incorporation of glycerol into diacylglycerol. These changes occur during the first 20-30 s of stimulation. We can show now that these changes are associated with a significant increase in the activities of lysophosphatidate acyltransferase, diacylglycerol kinase, and diacylglycerol acyltransferase which reaches a maximum during the first 60 s after stimulation. In vitro experiments with isolated parotid microsomes, the catalytic subunit of cAMP-dependent or Ca2+/calmodulin-dependent protein kinase, and with purified protein phosphatases indicate that the activation of enzyme activities in intact parotid gland cells results from protein phosphorylation. The two protein kinases seem to activate the three enzymes by phosphorylating the same site(s). Protein kinase C was almost ineffective. Glycerol kinase, glycerolphosphate acyltransferase, phosphatidate phosphohydrolase, CTP:phosphatidate cytidylyltransferase, and phosphatidylinositol synthase remained unchanged in the intact cell as well as during incubation with protein kinases in vitro. Lysophosphatidate acyltransferase, diacylglycerol kinase, and diacylglycerol acyltransferase can be activated by the two protein kinases also in microsomes from guinea pig cerebellum. It seems, therefore, that the regulation leading to rapid changes of enzyme activities during signal transmission in parotid acinar cells could be operative also in other cell types.

Acyltransferases↗
PubMed1989

A male accessory gland peptide with protease inhibitory activity in Drosophila funebris.

Male accessory glands of Drosophila funebris synthesize and secrete a peptide that shows a protease-inhibiting activity. Amino acid sequencing of the purified peptide revealed that the peptide consists of 63 amino acid residues. It is a serine protease inhibitor belonging to the pancreatic trypsin inhibitor (Kunitz) family. The inhibitory function and the kinetic characteristics of the inhibition have been examined with various substrates. The peptide possibly plays a role as an acrosin inhibitor involved in Drosophila reproduction.

Amino Acid Sequence↗
PubMed1989

Legionella infection of the colon presenting as acute attack of ulcerative colitis.

A 42-yr-old woman with long-standing ulcerative colitis of the descending colon, sigmoid, and rectum presented with bloody diarrhea, tenesmus, and high fever. Endoscopic findings were compatible with an acute attack of ulcerative colitis, which proved to be resistant to systemic corticosteroid treatment. In the presence of an acute abdomen with ascites and double-contoured colonic wall, hemicolectomy was performed. Postoperatively, high temperature, hyponatremia, and elevated liver enzyme levels persisted. Pleural effusions developed. Antibodies to Legionella pneumophila serogroup 3 were detected in the serum. Erythromycin therapy induced rapid improvement. In a massive submucosal edema of the affected colon, L. pneumophila of the same serogroup was demonstrated by direct immunofluorescence staining.

Acute Disease↗
PubMed1989

Mechanisms of short-term (second range) regulation of the activities of enzymes of lipid and phospholipid metabolism in secretory cells.

In isolated guinea pig parotid gland lobules the activities of the following enzymes were measured 30 sec after stimulation with either 2 X 10(-5) M isoproterenol or 10(-5) M carbachol: glycerol kinase (EC 2.7.1.30), glycerolphosphate acyltransferase (EC 2.3.1.15), lysophosphatidate acyltransferase (EC 2.3.1.51), phosphatidate phosphohydrolase (EC 3.1.3.4), diacylglycerol acyltransferase (EC 2.3.1.20), diacylglycerol kinase (EC 2.7.1.107), and CDP-diacylglycerol synthetase (EC 2.7.7.41). Lyso-phosphatidate acyltransferase, diacylglycerol kinase, and diacylglycerol acyltransferase exhibited significant increases following stimulation by both types of agonists. Stimulation of the activities of these three enzymes occurred also following in vitro incubation with the catalytic subunit of cAMP-dependent protein kinase or a Ca2+/calmodulin-dependent protein kinase II. These effects could be reversed by incubation with various protein phosphatases. When cells were first stimulated with either type of agonist, subsequent incubation with protein kinases was almost ineffective. Activation by the two types of protein kinases was not additive, indicating that they activate by phosphorylating identical sites on the enzyme proteins. The other enzymes examined showed no or only minor changes and their activities could not be affected by in vitro incubation with the two types of protein kinases. The results explain the rapid changes in acyl-group transfer from acyl-CoA to neutral lipids observed previously during the first seconds after stimulation of guinea pig parotid gland lobules with isoproterenol or carbachol (1). An analysis of a potential role of lipocortins for the regulation of phosphoinositide-specific phospholipases C reveals that these proteins do indeed inhibit these enzymes, but that this inhibition results from a calcium-dependent interaction of the lipocortins with the phospholipid substrate. A physiological role of lipocortins for the regulation of phospholipases is doubtful.

Acyltransferases↗
PubMed1989

[Facial hemiatrophy with monolateral fibrosis of all extraocular muscles].

Cases of facial hemiatrophy manifest a variety of symptoms of monolateral atrophic processes of the skin, muscles, and bones. The symptoms are usually progressive and may also involve the ocular bulb and the orbit. In this paper the authors report the case of a 53-year-old woman with congenital fibrosis of all extraocular muscles and restricted motility of the enophthalmic bulb in all directions of gaze. Since, in addition, the ipsilateral side of the face is affected by discrete atrophy, this case has been classified as congenital, nonprogressive facial hemiatrophy. The findings are compared with those in other published cases.

Blepharoptosis↗