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Biomedical subjects

J Schenk

Publications and source records attributed to J Schenk.

52 records · Page 3Linked to original sources
PubMed1978

Ultrastructural changes of colonic mucosa in patients with chronic laxative misuse.

Laxatives are amongst the most widely used and misused drugs. Especially the "irritant chathartics" are associated with severe cell poisoning. Electrolyte disturbances like potassium deficiency may occur as a result of enhanced potassium secretion into the colon. Ultrastructural studies of patients with chronic laxative misuse demonstrate, that this functional disorder is correlated with damage of the colonic epithelial cells consisting in stereotyped lesions as changes in microvilli, reduction and structural defects of cytoplasmic organelles and an increase of lysosomes and dense bodies. The lesions have a focal distribution and may explain the potassium loss from a morphological point of view.

Cathartics↗
PubMed1976

Therapeutic effects of HS-3, HS-6, benactyzine, and atropine in soman poisoning of dogs.

Investigations into the therapeutic properties of various combinations of the bispyridinium salts HS-3 and HS-6 and the cholinolytics atropine and benactyzine against soman poisoning in unanesthetized male beagles were performed. In our investigations we observed that: 1. The most effective protection against soman poisoning was attained if both oximes were applied early i.m. 6 min after intoxication together with the cholinolytics. 2. On the basis of clinical symptoms HS-6 proved to have a more intensive therapeutic effect than HS-3 upon early application. 3. If HS-3 was applied early after s.c. intoxication with low concentrations of soman (up to 3 LD50), a significant protection or reactivation effect on serium cholinesterase was measured. 4. When HS-3 was applied at the beginning of convulsions--generally 28 min after s.c. intoxication--it also raised the rate of surviving animals. 5. The maximal blood levels for HS-3 and HS-6 were measured 20-30 min after i.m. injection; the half-life values of HS-3 and HS-6 in plasma were 45-60 min.

Animals↗
PubMedDate not supplied

Effects of a supersulfated low molecular weight heparin (IK-SSH) on different hemostatic parameters.

In a phase I trial effects of a new supersulfated low molecular weight heparin (IK-SSH) on different hemostatic parameters were investigated in healthy volunteers. Parameters studied were activated partial thromboplastin time (aPTT), thrombin time, Heptest, anti-activated factor II (anti-FIIa) and anti-activated factor X (anti-FXa) activity, platelet adhesion, platelet count, platelet-induced thrombin generation time (PITT), bleeding time, antithrombin III, fibrinogen and several safety parameters. After single intravenous (i.v.) injections of IK-SSH (0.14, 0.33 and 0.66 mg/kg) aPTT, Heptest and PITT were strongly and dose-dependently prolonged. After ascending subcutaneous (s.c.) doses of IK-SSH (0.33, 0.66 and 1 mg/kg) aPTT, Heptest and PITT were prolonged in a dose-dependent manner. Repeat s.c. injections of 1 mg/kg IK-SSH for 5 days markedly prolonged aPTT, Heptest and PITT. No cumulative effects were observed. Anti-FIIa and anti-FXa activity were not or only slightly increased. Bleeding time, thrombin time and platelet adhesion were not significantly changed after i.v. and s.c. injections of IK-SSH. However, tissue factor pathway inhibitor (TFPI) concentration was markedly increased after each injection of IK-SSH and returned to the preinjection value 24 h later. IK-SSH prolongs aPTT, Heptest and PITT in a similar manner as other low molecular weight heparins but without significantly affecting thrombin time, FIIa and FXa activity. The release of TFPI may well be responsible for the prolongation of aPTT, Heptest and PITT. IK-SSH may be further developed as an antithrombotic agent.

Adult↗
PubMedDate not supplied

Effects of polysulfonate derivative (GL 522-Y-1) on coagulation in vitro and thrombosis in vivo.

We have investigated the influence of a polysulfonate derivative - GL 522-Y-1 - on platelet-induced thrombin generation time, platelet adhesion to siliconized glass, platelet aggregation induced by collagen and ADP, on aPTT, PT and TT in vitro and studied its antithrombotic effect in an animal model of thrombosis in vivo. In vitro, GL 522-Y-1 caused inhibition of ADP- and collagen-induced aggregation. In a dose-dependent manner this compound inhibited PITT, aPTT, and PT. GL 522-Y-1 did not prolong thrombin time. GL 522-Y-1 inhibited in vivo the laser-induced thrombus formation after intravenous and oral administration. On the basis of its unique antithrombotic properties, GL 522-Y-1 seems to open a new pathway in the field of antithrombotics.

Animals↗
PubMedDate not supplied

Controlled drinkers in comparison to abstinents and relapsed drinkers with regard to attitudes and social adjustment.

Referring to previous research and theoretical reflections the hypothesis was formulated that controlled drinkers follow a different model of alcoholism and its therapy than abstinents or relapsed drinkers. The patients of an abstinence-oriented program (N = 187) were interviewed at times between 1 1/2 and 4 1/2 years after treatment. According to their self-classification, three outcome groups were formed which were highly significantly differentiated by two discriminant functions. Symptom measures and subjective improvement following treatment had the highest coefficients on the first discriminant function, whereas the attitude toward alcoholism had the highest coefficients on the second one. On the first discriminant function the abstinents had the highest score, followed by the controlled drinkers and the relapsed ones. The differences between the three groups are significant. However, the difference between abstinents and controlled drinkers is due to the direct evaluation of therapy; the social adjustment measures do not differ between these two groups. On the second discriminant function the centroid of controlled drinkers stands out very much against the centroids of abstinents and relapsed drinkers, which are similar. Consequences are discussed.

Adult↗
PubMedDate not supplied

A study of acrylic resin denture base material distortion using computer-aided holographic interferometry.

A holographic interferometer for investigating deformations of dental prostheses is described. Residual stress relaxation resulting from the polymerization of acrylic resin dentures is qualitatively studied during the first 48 hours following fabrication. The resulting fringe patterns show a symmetry that is correlated to the shape of the denture. A quantitative analysis of the interferograms was performed with the aid of a computer program. The computer-aided holographic interferometer was tested using disk-shaped acrylic resin materials. Dimensional deformations resulting from temperature changes were measured with an accuracy better than 0.2 microns. Because of the aging of the resin material, the reaction to temperature changes may differ as a function of time and may be studied using quantitative comparison of deformation plots. For convenience, the original object shape can be added to or subtracted from the graphical deformation data.

Acrylic Resins↗