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Biomedical subjects

A Hagen

Publications and source records attributed to A Hagen.

At least 55 records · Page 3Linked to original sources
PubMed1990

[Potential cardiotonic agents. 10. Synthesis and positive inotropic action of 5-(4-pyridinyl)- and 5-phenyl-substituted 2-alkylthio-3-cyan-pyridines and their S-oxidation products].

The alkylation of the 5-(4-pyridinyl)- and 5-phenyl-substituted 3-cyan-2(1H)-pyridinethiones 1 with alkyl iodides and halomethylcarbonyl compounds led to the 2-alkylthio-pyridines 3a-c, 3e, 3f and the thieno[2,3-b]pyridines 4, respectively. In an other way the 2-ethylthio-5-(4-pyridinyl)pyridines 3b and 3d were formed from the corresponding 2-chloroderivatives and ethylmercaptan. By means of oxidation of the 2-alkylthio-pyridines 3 with 3-chloroperbenzoic acid and potassium permanganate, respectively, the 2-sulfinyl- and 2-sulfonyl-pyridines 5 and 6 were obtained. The 3-cyano-5-(4-pyridinyl)pyridine-2-sulfonic acid 7 was prepared by oxidation of the 2(1H)-pyridinethione 1a with potassium permanganate. Some derivatives possess positive inotropic properties.

Animals↗
PubMed1990

[Synthesis and pharmacologic properties of pranolium and its optical isomers].

Propranolol is a well-known powerful betareceptor-blocking agent. Its quaternary dimethyl derivative, designated as pranolium was firstly prepared by Lucchesi. Compared to propranolol it possesses no betareceptor-blocking activity and no local anaesthetic properties but shows the same antiarrhythmic action as the starting material. The synthesis of pranolium and its optical isomers starting from the corresponding propranolol derivatives is described. Their pharmacological activities have been tested. No significant differences regarding the pharmacological action could be observed.

Aconitine↗
PubMed1990

[Potential cardiotonic agents. 6. Synthesis and cardiovascular properties of 5-(4-pyridinyl)-, 6-methyl-5-(4-pyridinyl)- and 6-methyl-5-phenyl-substituted 3-cyano-2-oxaalkyoxy-pyridines].

The headline compounds were prepared by the reaction of 2-chloropyridines 1-3 with the appropriate alcohols in presence of potassium hydroxide and the sodium alkoxides, respectively. Especially some of the 3-cyano-2-hydroxyalkoxy-5-(4-pyridinyl)pyridines showed remarkable positive inotropic potency and, additionally, a vasodilator activity. In spontaneously beating isolated guinea pig atria they had a greater activity than amrinone.

Amrinone↗
PubMed1990

[Potential cardiotonics. 7. Synthesis and cardiovascular effects of 5-(4-pyridinyl)-, 6-methyl-4-(4-pyridinyl) and 6-methyl-5-phenyl-substituted 3-cyano-2-aminoalkylamino-pyridines].

The title compounds were synthesized by treating of 2-chloro-pyridines 1-3 with the appropriate aminoalkylamines or piperazines. In isolated guinea pig atria some compounds showed greater positive inotropic activity than amrinone. Heart rate was decreased or remained unchanged. In anesthetized dogs some derivatives exerted a dose-dependent increase in myocardial contractility and, additionally, a decrease in blood pressure.

Animals↗
PubMed1990

[Potential cardiotonic agents. 8. 2-acyloxyalkylamino-, 2-acyloxyalkoxy-, and 2-acylaminoalkylamino-3-cyan-5-(pyrid-4-yl) pyridine].

By acylation of our previously described cardiotonic active 2-hydroxyalkylamino, 2-hydroxyalkoxy, 2-aminoalkyl-amino and 2-piperazino substituted 3-cyano-5-(4-pyridinyl) pyridines with acetic anhydride, propionic anhydride or aroyl and heteroaroyl chlorides, respectively, the corresponding in position 2 O- or N-acylated 3-cyano-5-(4-pyridinyl)pyridines were prepared. Cardiovascular activity of the obtained derivatives is discussed in comparison with that of the parent compounds.

Amines↗
PubMed1989

[Comparative ultrasound and computerized tomography studies of lumbar intervertebral disks and the lumbar canal].

Sonography and computerised tomography were carried out on 61 lumbar segments (L5/S1, L4/5, L3/4) of 30 patients not having vertebrogenous symptoms. Transabdominal lumbar sonography with a 3.5 MHz sector probe proved to be a valuable imaging method, allowing to demonstrate the shape and dorsal outline of the lumbar discs. Bowl-shaped, right-angled and funnel-shaped configurations of the dorsal spinal canal are typical findings. The interpretation of the ultrasonic tomograms and the identification of normal anatomy are improved through comparative imaging by computerised tomography.

Humans↗
PubMed1989

[Potential cardiotonic agents. 4. Synthesis, cardiovascular activity, molecular and crystal structure of 5-phenyl- and 4-(4-pyridinyl)-substituted 2(1H)-pyridinethiones].

Cyclisation of the vinylogous amidinium salt 1 or the 4-ethoxy- and 4-morpholino-3-butene-2-ones, respectively, 4 and 6 with cyano-thioacetamide yielded the 5-(4-pyridinyl)-, 6-methyl-5-(4-pyridinyl)- and 6-methyl-5-phenyl-, respectively, substituted 3-cyano-2(1H)-pyridinethiones 3, 5 and 7. The 2(1H)-pyridinethiones 3, 5 and 7a as well as the in 3-position unsubstituted or carbamoyl substituted derivatives 8 and 9 were obtained from the corresponding 2-chloro-pyridines and potassium sulfide, too. Especially compound 5 showed remarkable positive inotropic potency and, additionally, vasodilator activity. The molecular and crystal structure of 5 have been determines by X-ray structure analysis. Based on the molecular structure charge distribution and electrostatic potential were evaluated. The results are discussed in comparison with those of milrinone.

Animals↗
PubMed1989

[Potential cardiotonic agents. 1. Synthesis and pharmacologic properties of 3-cyano-2-oxaalkylamino-5-(4-pyridinyl)pyridines].

Synthesis, physicochemical properties and evaluation of positive inotropic and vasodilator activities are described in a series of substituted 2-amino-3-cyano-5-(4-pyridinyl)pyridines. Some of the 2-oxaalkylamino derivatives showed remarkable positive inotropic activities and, additionally, a decrease in blood pressure. The most potent compounds 11 and 13 have a greater activity than amrinone.

Aminopyridines↗
PubMed1989

[Potential cardiotonic agents. 2. Synthesis and pharmacologic properties of 5-(pyri-4-yl)- and 5-phenyl substituted 3-cyano-6-methyl-2-oxaalkylaminopyridines].

The authors describe the preparation, the physicochemical properties and the results of evaluation of positive inotropic and vasodilator activities in a series of 5-(4-pyridinyl)- and 5-phenyl-substituted 3-cyano-6-methyl-2-oxaalkylamino-pyridines. Some of the compounds are comparable in their positive inotropic potency to that of amrinone and cause, additionally, a decrease in blood pressure.

Aminopyridines↗
PubMed1989

[Incidence of abnormalities following the use of hormonal contraceptives].

In order to get evidence about the incidence of malformations as because of intrauterine exposition of steroids as after cessation of hormonal contraception in dependence on the time interval between the last intake of hormonale contraceptives (h.c.) and on different pills 5,866 pregnant women have been entered into a case-control-study. 2,834 pregnant women had taken h.c. during pregnancy or got pregnant within 6 menstrual cycles after discontinuation of pills (= cases). For control the data of 3,032 pregnant women were examined. These one had never taken pills or their pregnancy occurred after 7 menstrual cycles after cessation of pill ingestion. Perinatal mortality, Apgar-score (5 min) and incidence of twins were not different in cases and controls. The incidence of malformations was significant (p less than or equal to 0.01) higher in controls than in cases. It depended on age in form of an increase with rising age. The incidence of malformations in both groups increased significantly (p less than or equal to 0.01) with a rising cigarette consumption during pregnancy. The results of this study suggest that smoking regarding malformations represents a higher risk than the intake of h.c.

Abnormalities, Drug-Induced↗
PubMed1989

[Ultrasound tomography following surgery of tumors of the cerebellopontile angle].

After operations of the posterior fossa, ultrasonic tomography is a suitable noninvasive imaging procedure. After osteoclastic trepanation 45 patients were investigated with ultrasonic tomography. Below it were 18 patients with tumours of the cerebellopontine angle. A sector probe with a frequency of 3,5 MHz was used for the sonographical procedure. Ultrasonographical cross-sectional images were produced from occipital-retroauriculare or suboccipital. Solid processes have a definable echodense structure. Cystic processes and substantial defects of the brain are echopoor or echofree. Ultrasonic tomography allows an aimed application of CT controls.

Cerebellar Neoplasms↗
PubMed1988

[Ultrasound tomography in postoperative monitoring of infratentorial space-occupying lesions].

After osteoclastic trepanations of the posterior fossa for cystic or solid processes of the cerebellum and the cerebellopontine angle, ultrasonic tomography is a suitable imaging procedure. A mechanical sector probe with a frequency of 3.5 MHz is recommended as transducer. The postoperative ultrasonic findings are the basis for the sonographic observation of the further evolution. Cystic and solid processes can be localized and their dimensions metrically determined by means of multiple plane cross-sectional imaging. Ultrasonic tomography is recommended as a primary diagnostic method owing to its lack of invasivity and radiation exposure, simple handling and repeatability. As a consequence, CT examinations can be better aimed.

Adult↗
PubMed1988

[Transabdominal lumbal ultrasonic tomometry--sonographic measurement of the lumbar spine].

Transabdominal sonography was carried out on 102 lumbar segments that were myelographically without abnormalities of the dural sack. A sector probe with a frequency of 3.5 mHz was used as transducer. Diameters of lumbar discs and lumbar canal were measured in a transversal plane. Echogenicity of the epidural fat in the lumbar canal allows to depict both the limitation of the dorsal outline of the lumbar discs and the dorsolateral vertebral arch. The following mean values were calculated for the spinal canal: Sagittal diameter-L5/S1:18.5 mm, L4/5:20.4 mm, L3/4:19.9 mm Transversal diameter-L5/S1:20.9 mm, L4/5: 21.4 mm, L3/4:21.2 mm Sonographic measurement of the spinal canal is possible.

Adolescent↗