Search PubMed⌕ Search

Biomedical subjects

W Schulze

Publications and source records attributed to W Schulze.

At least 163 records · Page 9Linked to original sources
PubMed1981

Electroncytochemical studies on changes of the adenylcyclase activity following experimental hypoxia and ischaemia in perfused rat hearts.

Changes in activity and localization of adenylcyclase were studied in rat heart perfused according to LANGENDORFF after N2-and CO-hypoxia and ischaemia. Under hypoxic conditions an increase of adenylcylase activity was found in the first minutes. Following 3 h nitrogen or 30 min CP perfusion the intensity of reaction was diminished. This later decrease of reaction intensity was not encountered under ischaemic conditions. Changes in localization were not observed either in hypoxia or in ischaemia. After reserpine or propranolol pre-treatment the posthypoxic/ischaemic initial activity-increase did not occur. It is assumed that the early increase in adenylcyclase activity (reaction intensity) following hypoxia/ischaemia is due to endogenous catecholamine release.

Adenylyl Cyclases↗
PubMed1981

[On the methodology of the determination of alkylating activities of nitrogen mustards with nitrobenzylpyridine (NBP) in biological material (author's transl)].

It is dealt with modifications to the spectrophotometric determination of the alkylating behaviour of bifunctional nitrogen mustards with 4-(4'-nitrobenzyl)pyridine (NBP). The authors succeeded in characterizing spectrophotometrically, by means of a one-phase procedure, not only soluble, but also difficultly soluble, therapeutically known and newly synthetized mustards in regard to their alkylating behaviour. In the framework of in vitro studies, the authors report of experimental details of the proper preparation of biological material for the determination of residual activities, the analytical approach being always depending on the structure of the respective mustard. The differences in the time courses of the acylating attacks in serum, blood and suspensions of leukaemic cells are demonstrated by the example of some selected nitrogen mustards.

Alkylating Agents↗
PubMed1979

Mass isolation of cell surface membrane fragments from pigeon heart.

Cell surface membrane fragments were isolated and purified by successive rate zonal and isopycnic centrifugation of calcium oxalate-loaded pigeon heart microsomes in sucrose density gradients. The most highly purified cell membrane fraction sediments at a buoyant density of 1.105 g/ml. Some of the membrane pieces are present as open fragments and leaky vesicles, while others form tightly sealed vesicles of both inside-in and inside-out membrane orientation. The pigeon heart cell membrane preparation exhibits high (Na+ + K+ + Mg2+)-ATPase and adenylate cyclase activities. Additional activity of these enzymes is uncovered by sodium dodecyl sulfate and alamethicin, respectively. Electron microscopic inspection of the cell surface membrane preparation revealed (a) a predominance of thick-walled vesicles with smooth surfaces on negative staining and (b) binding of concanavalin A to the bulk of isolated membrane pieces following their incubation with the lectin.

Adenylyl Cyclases↗
PubMed1979

[Cancerostatic effect of some fluorenone azomethines tested against leukemia L 1210 (author's transl)].

Eight of fifteen Fluorenone-Azomethines without alkylating function have been found effective against the leukemia L 1210. Little modifications concerning the structure of the compounds caused loss of effectiveness. It seems remarkably that one corresponding derivative with a nitrogen mustard group (4) was ineffective. Correlations between chemical structure and biological effect have not yet been found.

Animals↗
PubMed1979

[Carbonyl derivatives of tilorone. Part 2: On the cancerostatic activity of carbonyl derivatives of tilorone (author's transl)].

A series of carbonyl derivatives of tilorone was synthetized by reaction with appropriate amino compounds, mainly hydrazines and hydrazides. The condensation products obtained were tested for cancerostatic activity against the murine leucaemia L 1210 and the Walker carcinosarcoma of the rat. Only three of the substances under investigation (1a, 5, 13) proved active against the Walker carcinosarcoma, one of which (5) being comparable to tilorone. No activity against L 1210 was observed, even tilorone exerted no effect. The reduction in activity against the Walker carcinosarcoma which resulted from the carbonyl substitution might be caused by a decrease in the ability to intercalate into DNA.

Animals↗
PubMed1979

[Inhibition of concanavalin A and phytohemagglutinine P mediated agglutination of L 1210 cells by different azomethines and possible relations to their cytostatic activity (author's transl)].

Compounds of a special azomethine type have been tested on their activity against concanavalin A and phytohemagglutinine P mediated agglutination of leukemia L 1210 cells. With exception of two compounds possessing a bis-(beta-hydroxyethyl) amino group at the phenyl moiety in para-position to the azomethine group all substances considerable inhibited agglutination of L 1210 cells. In vitro active concentrations are also obtained in animal experiments at least for a short time at the site of injection (i.p.) The importance of cellular reactions for effectivity in vivo is discussed.

Agglutination↗
PubMed1977

[Laryngeal ruptures (author's transl)].

Laryngeal ruptures are caused by vertical traction on the larynx and trachea, mainly by pushing the chin upon a dashboard or by so called whiplash trauma. Forteen cases could be classified in supraglottic ruptures, subglottic rupture and laryngotracheal ruptures. In supraglottic ruptures the epiglottis and parts of the ventricular folds are separated from the thyroid cartilage. In subglottic rupture the cricothyroid membrane is ruptured. The most common type is the partial avulsion of the trachea from the cricoid cartilage. In all types the laryngotracheal axis is kinked and scar tissue grows into the larynx. To avoid consecutive stenosis of the larynx in every case a straight dilator should be introduced as an internal splint.

Humans↗