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Biomedical subjects

J Baumann

Publications and source records attributed to J Baumann.

At least 73 records · Page 4Linked to original sources
PubMed1981

[Influence of Hydroxy-1,4-naphthoquinone Derivatives on Prostaglandin synthesis (author's transl)].

Inhibition of cyclo-oxygenase reaction during prostaglandin formation in the renal medulla of the rat by 1,4-naphthoquinone derivatives is compared with the known enzyme inhibition properties of natural and synthetic flavonols. Structure-activity relationship study shows strong correlation between chemical properties (vicinal hydroxy-oxo structure of planar molecules) and physicochemical parameters (polarity and acidity). The most potent compounds are 2-ethyl-5-hydroxy-1,4-naphthoquinone (9) and 2-methyl-3-hydroxy-1,4-naphthoquinone (6).

Animals↗
PubMed1980

Flavonoids and related compounds as inhibition of arachidonic acid peroxidation.

Until now only few data have been reported on biochemically explicable pharmacological effects of flavonoid structures. When tested against arachidonic acid metabolism many flavonoids were found to be effective against the lipoxygenase and cyclo-oxygenase pathways. Some flavonoids were predominant inhibitors of either cyclo-oxygenase or lipoxygenase, others were equally effective against both enzymes. Therefore, these compounds proved to be useful tools to elucidate fatty acid peroxidation problems.

Animals↗
PubMed1980

Hemophilia A in a phenotypic female with normal male karyotype associated with a low factor XII level.

Hemophilia A was detected in a 40-year-old black Gabonese female prior to thoracic surgery for empyema. The diagnosis of mild hemophilia A was supported by the findings of low factor VIII coagulant activity (VIII:C 4%), normal levels of factors VIII related antigen (VIIIR:Ag) and VIII von Willebrand (VIIIR:WF), without detectable circulating anticoagulant. Neither the patient nor her immediate relatives had past histories of abnormal bleeding. The physical features were phenotypically female with developed breasts, pubic hair and normal external genitalia: however, she had primary amenorrhea, a blind vagina with no uterus and her karyotype was 46,XY. These findings are consistent with the diagnosis of testicular feminization thereby explaining the apparent contradiction between the phenotype and the known six-linked inheritance of hemophilia A. In addition to factor VIII deficiency a low level of factor XII (20%) was detected although it cannot be concluded whether the patient is truly factor XII deficient or whether she represents a low variant of the normal distribution.

Adult↗
PubMed1979

A structure-activity study on the influence of phenolic compounds and bioflavonoids on rat renal prostaglandin synthetase.

The stimulating or inhibiting influences of 33 phenolic compounds on the prostaglandin synthetase of rat renal medulla were tested. Dihydroxyphenylcarbonic acids clearly proved to be activators of the prostaglandin synthetase. Dimethoxyphenylcarbonic acids were ineffective. Aminoethylphenols as well as p-substituted monohydroxybenzenes with a carbonic acid side chain were clear stimulators in contrast to their alkyl derivatives which are pronounced inhibitors. Among the tested bioflavonoids (+)-cyanidanol-3 and morin were inhibitors of the prostaglandin synthesis. Flavonoids with polar substitution in 3,5,7-position such as rutin on the other hand showed activating properties.

Animals↗
PubMed1979

(+)-Cyanidanol-3 as inhibitor of prostaglandin synthetase. Studies on renal medulla and liver of the rat in vitro and in vivo.

(+)-Cyanidanol-3 inhibits the prostaglandin synthetase of the renal medulla and of the liver of rats in vitro and after treatment of the animals with 200 mg/kg. A half-maximal inhibition of the enzyme was obtained with 5 . 10(-5) M cyanidanol. If the microsomal inhibitor CFT1201 is first applied, the inhibitory effect in vivo of 50% is increased to 80%. It is supposed that cyanidanol is converted to metabolites which, according to our earlier studies, activate the enzyme system. An enzyme activity of the rat liver was measured which - with a turnover of 18-20% - was significantly higher than the values obtained by other authors.

Animals↗
PubMed1978

[A balanced synthetic diet (Berlamin) in colonic surgery (author's transl)].

In preparation for surgery of the colon and rectum 50 patients were fed an oral balanced synthetic diet. Additionally, antibiotics were administered. With the exception of 4 patients the bowel was completely free from faeces. During the preoperative period, averaging 5 days, no pathological laboratory findings were observed. On the 5th day of the oral diet feeding there was a total N-retention rate of +2,8 +/- 1,2 N/day.

Colon↗
PubMed1977

Comparison of the in vitro conversion of estradiol-17 beta to estrone of normal and neoplastic human breast tissue.

Specific activity of 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) was measured in 48 tissue specimens of human female breast cancer and, in addition, 48 nonmalignant tissue specimens obtained in each case from the same cancer-bearing breast. In all cases the nonmalignant tissue showed greater conversion of estradiol-17 beta into estrone than the neoplastic tissues. In normal human breast tissue of premenopausal women specific enzyme activity depended on the phase of the MENSTRUAL CYCLE: the highest values of 17 beta-HSD activity were found in the early secretory phase. To determine the intracellular distribution of the 17 beta-HSD, purified microsomes, mitochondria, peroxysomes, lysosomes, nuclei and cytosol fractions were prepared. The purity of each fraction was monitored by marker enzymes. It was found that the 17 beta-HSD was mainly located in mitochondria and microsomes. Furthermore it could be demonstrated that the microsomal enzyme was bound tightly to the membranes of the endoplasmic reticulum, while the mitochondrial 17 beta-HSD was mainly associated with the outer membranes of the organelle. Kinetic parameters (Km-values, coenzyme requirements and maximal velocities) of a cytoplasmic, nuclear, mitochondrial and microsomal 17 beta-HSD of normal and neoplastic human mammary tissue were compared. Maximal velocity was highest in enzyme preparations of normal mammary tissue obtained from premenopausal women in the early secretory phase. Km-values wrere nearly identical in normal and neoplastic mammary tissue preparations (approx. 1 X 10(-6) M). NAD was more efficient than NADP as a cofactor. For the conversion of estradiol to estrone the optimum temperature was approximately 40 degrees C and the optimum pH 9.5. For the reduction of estrone the optimum pH was 6.5. Sulphydryl groups were shown to be essential for catalysis.

Breast↗