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V Graef

Publications and source records attributed to V Graef.

At least 19 recordsLinked to original sources

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Cell Fractionation↗

Evaluation of serum and urinary estrogen levels in male patients with HIV-infection.

Several endocrine functions are described which are altered in patients with human immunodeficiency virus infection. However, there is limited information available on estrogens and their function in these patients. The aim of this study was to relate the stage of the disease with urinary and serum estrogens and the influence of heroin consumption on gonadal steroids. Forty human immunodeficiency virus infected outpatients without AIDS or the clinical picture of AIDS were involved in this cross-sectional study. The subjects were divided in two groups: heroin addicts and non heroin addicts. Blood samples were taken and 24 h urines collected. Serum follicle stimulating hormone, luteinizing hormone, prolactin, estrone, estradiol, testosterone and urinary total estrogens were measured by commercially available radioimmunoassays. Prolactin levels were not affected in the patients. However, compared with controls, follicle stimulating hormone and luteinizing hormone were significantly higher for both groups tested. In contrast, the elevated serum estrone levels were significantly lower expressed in the patients with heroin abuse compared to those of the other group. Urinary estrogens in human immunodeficiency virus infected patients of both groups were found to be higher than those compared to healthy controls. Since these drugs are known to enhance estrogen levels, we conclude that other factors are modulating estrogen formation and degradation in these patients.

Adult↗

Relationship between 1,25-dihydroxyvitamin-D, calcium and uric acid in urinary stone formers.

In order to clarify the role of 1,25-dihydroxyvitamin-D [1,25-(OH)2-D] in calcium stone formation, correlations between 1,25-(OH)2-D serum levels and levels of calcium, phosphate and uric acid (UA) in serum or urine and between the 1,25-(OH)2-D serum level and age were analyzed in 111 formers of urinary stones (57 Ca stones) and in 44 controls. Furthermore, 1,25-(OH)2-D serum levels as well as levels of Ca, phosphate and UA in serum and urine from formers of different urinary stones and controls were compared. 1,25-(OH)2-D serum levels were determined by a radio-receptor assay based on a calf thymus receptor. 1,25-(OH)2-D serum levels correlated positively with urinary UA excretion in formers of Ca stones and with urinary Ca excretion in formers of Ca stones and controls. In formers of Ca stones urinary Ca excretion was higher and serum phosphate was lower than in controls. 1,25-(OH)2-D serum levels did not differ. 1,25-(OH)2-D serum levels decreased with increasing age in controls, but not in stone formers. Our results show that urinary UA and 1,25-(OH)2-D in serum co-influence Ca stone formation, and they suggest that there is an increased sensitivity to 1,25-(OH)2-D in formers of Ca stones.

Age Factors↗

Evidence of impaired cartilage/bone turnover in patients with active ankylosing spondylitis.

OBJECTIVES: To compare serum markers of bone formation with the urinary excretion of pyridinium crosslinks (PYR) as a possible measure of bone and cartilage degradation which would detect changes in bone metabolism in patients with ankylosing spondylitis (AS) and to relate them to influences of inflammatory disease activity, and to treatment. METHODS: In 62 patients with AS, serum osteocalcin, alkaline phosphatase (ALP), and skeletal ALP isoenzyme levels were evaluated concurrently in comparison with urinary excretion of pyridinium cross links and were compared with values in 50 healthy controls. RESULTS: Osteocalcin concentrations in AS patients were in the middle normal range (3.5 (SD 1.2) ng/ml) and did not differ significantly from those in control subjects (4.2 (1.3) ng/ml); the same was true for ALP and skeletal ALP isoenzyme fraction (AS: ALP 149 (50.3) U/l, skeletal ALP 12.8 (4.1) micrograms/l; controls: ALP 133 (25.2) U/l, skeletal ALP 11.9 (4.3) micrograms/l). The urinary levels of PYR in AS (51.2 (25.2) nmol PYR/mmol creatinine) were significantly increased compared with controls (33.9 (12.4) nmol PYR/mmol creatinine (p < 0.001)). In the AS group there was a positive correlation between urinary excretion of PYR and inflammatory disease activity (erythrocyte sedimentation rate (ESR)) (r = 0.6, p < 0.0001) and C reactive protein (CRP) (r = 0.3, p = 0.02), but no significant correlation was found with ESR, CRP, and markers of bone formation. CONCLUSIONS: Bone metabolism in patients with AS is characterised by normal bone formation and enhanced cartilage/bone degradation, suggesting that impaired bone turnover is pronounced in active disease. The results clearly indicate that this comparison can be used to demonstrate impairment of cartilage/bone metabolism which correlates with disease activity. The data obtained further emphasise the importance of measuring both serum variables and urinary excretion of PYR crosslinks to obtain adequate evaluation of cartilage/bone metabolism in patients with AS.

Adult↗

Adrenal secretion of cortisol in patients with rheumatoid arthritis.

We studied secretory activity of the adrenal gland by determining cortisol blood levels throughout a 24-h cycle at 2-h intervals in 26 patients with rheumatoid arthritis (RA), not previously treated with glucocorticosteroids or disease modifying drugs. In patients with low erythrocyte sedimentation rates [(ESR) up to 40 mm/h] and medium disease activity (ESR between 40 and 80 mm/h), cortisol maxima and minima shifted to earlier times of the day whereas in patients with high activity (ESR higher than 80 mm/h) the circadian rhythm was lost or markedly reduced. The inflammatory activity of the RA significantly correlated with the adrenal cortisol secretion (linear regression analysis between ESR and the arithmetic mean value of cortisol throughout a 24-h cycle with a coefficient of regression r = 0.63, n = 26, p less than 0.001). The influence of mediators of inflammation, such as interleukin 1, on hypothalamic centers, stimulating the hypothalamus-pituitary-adrenal axis, is discussed.

Adrenal Glands↗

Enzyme catalytic concentrations in human plasma after a marathon.

Blood was obtained from 11 males participating in the Berlin marathon 1986, directly before and after the marathon, and on the three following days. Several observations were made: a) catalytic concentrations (activity) of creatine kinase (CK), lactate dehydrogenase (LDH), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (AP) increased directly after the marathon or on the three following days; b) Cholinesterase (CHE), amylase (AML) and gamma glutamyltransferase (GGT) decreased directly after the marathon; c) the time course of AP and LDH isoenzyme activity after the race indicated an elimination from plasma to lower values than those originally observed before the run.

Alanine Transaminase↗

Thin-layer chromatography--the forgotten alternative for the quantitative determination of steroids.

We have developed a high performance thin layer chromatography (HPTLC) system for quantitative determination of androgens, corticosteroids, mineralocorticoids and gestagens on silicagel KG-60 HPTLC-plates with different solvent systems. A complete separation of androgens, gestagens and metabolites was achieved with dichlormethane/cyclohexane/acetone (70:25:5). Corticosteroids, mineralocorticoids and their derivatives were completely separated with diethylether/isooctane/isopropanol (70:25:5). The quantitative in situ fluorescence determination was carried out after post-chromatographic derivatization with cinnamic aldehyde, 4-dimethylaminobenzaldehyde and sulfuric acid. The sensitivity of detection was found between 500 pg and 1 ng per spot. The steroid metabolism as catalysed by rat liver microsomal oxidoreductases was measured by these procedures, and was compared with determination of steroids by gas chromatography (GC). According to HPTLC, steroids were reduced by NADPH-5 alpha-reductase (EC 1.3.1.4) in the order progesterone greater than testosterone greater than aldosterone greater than cortisol greater than corticosterone. The enzyme activities as measured by HPTLC agree well with those obtained by GC (r = 0.94). When turnover of enzyme assays, speed of determination, detection limit, application to labile steroids and costs of steroid determination are considered, all points speak in favour of HPTLC.

Adrenal Cortex Hormones↗

Effect of flutamide on 5 alpha-reductases, 5 beta-reductases, and 3-hydroxysteroid dehydrogenases in rat liver.

Flutamide (0.5 mM) decreased in vitro the activity of NADH-5 alpha-reductase (substrate testosterone) in liver homogenate of male and female rats, whereas no change of activity of NADPH-5 alpha-reductase was observed. NADH- and NADPH-5 beta-reductase activity increased only in liver of female, but not of male rats. NAD+-3 beta-hydroxysteroid dehydrogenase and NAD+-3 alpha-hydroxysteroid dehydrogenase (substrate 5 alpha-dihydro-testosterone) in liver homogenate from female rats were inhibited by flutamide (0.5 mM), whereas the activity of NADP+-3 alpha-hydroxysteroid dehydrogenase (substrate 5 alpha-dihydrotestosterone) and of NAD+-3 alpha-hydroxysteroid dehydrogenase (substrate 5 beta-dihydrotestosterone) increased in presence of flutamide. The activity of NADH- and NADPH-5 alpha-reductase decreased after flutamide administration to female rats at a dose of 5 mg per day for 7 days.

3-Hydroxysteroid Dehydrogenases↗

[Endocrine rhythms in patients with rheumatoid arthritis: possible neurohormonal influence on immunological reactions].

Recent studies are reporting on an influence of ACTH and prolactin in physiological dosages on the intensity of the immune response in the animal model of adjuvant arthritis. Therefore, we studied the circadian secretion patterns of ACTH, cortisol and prolactin by measurements throughout a 24-hour cycle in two-hour intervals in patients with rheumatoid arthritis with different inflammatory activity of the disease. We only investigated patients who never before were treated with corticosteroids and drugs like gold, d-penicillamine or immunosuppressive drugs. The circadian secretion patterns of cortisol and ACTH were disturbed in most patients. High inflammatory activity was accompanied by severe disturbance of the circadian rhythm, whereas patients with low inflammatory activity showed a nearly normal secretion pattern. Also the measurements of prolactin showed a tendency of loss of circadian rhythm in relation to the inflammatory activity of the disease. According to the found changes of endocrine regulation of ACTH, cortisol and prolactin, an influence of mediators of inflammation on hypothalamic centers, analogous to endogenous pyrogen in fever should be discussed.

Adrenocorticotropic Hormone↗

High dosage desferrioxamine therapy in a female patient with acquired aplastic anaemia and transfusion siderosis.

A 32 year old woman with severe aplastic anaemia required frequent transfusions and consequently developed hyperferrioxaemia (54 microMol/l) and hyperferritinaemia (1,700 ng/ml). For the treatment of transfusion siderosis she was given 18 high dose courses each comprising 35 g of desferrioxamine. Because of pre-existing thrombocytopenia (platelet count 5 X 10(9)/l) the iron chelating agent was given by continuous intravenous infusion over 3 1/2 days. High dose desferrioxamine had to be abandoned because of severe bone pain. The desferrioxamine infusions achieved a negative iron balance, iron loss after each infusion being 100 to 200 mg in the urine and 400 mg in the faeces. Serum iron and ferritin concentrations fell almost to normal. This report shows that faecal iron excretion must be taken into account in assessing the balance of iron input and output during desferrioxamine treatment.

Adult↗

Properties and biochemical characterization of NADH 5 alpha-reductase from rat liver microsomes.

NADH 5 alpha-reductase is present in microsomes of various rat organs: heart and skeletal muscle, liver, adrenal glands, kidney, testes and prostate. The enzyme from rat liver microsomes utilizes B-hydrogen from the coenzyme NADH for steroid reduction. After solubilization of the enzyme with the nonionic detergent lubrol, phosphatidylcholine is necessary to restore the activity. This reactivation of the enzyme activity is paralleled by a corresponding increase of Vmax for testosterone (17 beta-hydroxy-4-androsten-3-one). Km and Vmax for testosterone change, Km and Vmax for the coenzyme NADH remain constant with an alteration of phosphate concentration in the incubation medium. The NADH 5 alpha-reductase is inhibited by numerous substances: amytal, phenobarbital, mepacrin, thenoyltrifluoracetone, gallic acid propyl ester, dicoumarol, pentachlorophenol, NADP and antibodies against rat liver NADPH ferrihemoprotein reductase. Antibodies against rat liver cytochrome-b5 reductase cause an activation of NADH 5 alpha-reductase.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗

Effect of medroxyprogesterone acetate on steroid reductases in rat liver.

Male and female rats were treated with medroxyprogesterone acetate (17 alpha-acetoxy-6 alpha-methyl-pregn-4-ene-3,20-dione, MPA) 600 mg/kg body weight i.p. daily for seven days. The steroid metabolizing enzymes in liver microsomes and liver homogenate were measured following MPA treatment and in control rats. The specific activity of NADPH- and NADH-5 alpha-reductase in female rats and of NADPH-5 alpha-reductase in male rats decreased by the treatment. NADP+- and NAD+-3-hydroxysteroid dehydrogenase activities were lower in female MPA rats if compared to untreated animals. In male rats only NADP+- and NAD+-3 beta-hydroxysteroid dehydrogenase activities (substrate 5 beta-dihydrotestosterone) were diminished by MPA administration. There was no effect on the cytoplasmatic 5 beta-reductases. Plasma concentrations of luteinising hormone (LH), testosterone and androstenedione were lowered by MPA treatment.

3-Hydroxysteroid Dehydrogenases↗

[Effect of cocoa on excretion of oxalate, citrate, magnesium and calcium in the urine of children].

Cocoa is a strong carrier of oxalic acid (average: 400 mg per 100 g). In three calcium oxalate stone formers clinical observation had been suggestive of excessive intake of cocoa products contributing to calculus formation. We studied the effect on renal oxalate excretion of an oral cocoa load (30 g per m2 body surface given on 2 consecutive days) in 12 former stone formers (group 1), 14 children with isolated microscopic haematuria (group 2), 13 healthy boys (group 3), and 12 healthy girls (group 4). A new enzymatic method was used to measure oxalic acid in cocoa products as well as in urine samples by a two step reaction: 1. Oxalate decarboxylase, 2. formiate dehydrogenase with photometry of NADH. In addition, the daily excretion of the following substances was measured: Citrate, magnesium, and calcium. There was a significant increase of urinary oxalate excretion from an average of 14.5 mg/24 hours before to an average of 22.2 mg/24 hours after the load in healthy children, and a similar increase in stone formers, but not in children with microscopic haematuria. The excretion of citrate and magnesium did not change following cocoa intake. The calcium excretion was higher in stone formers than in the other groups, but the difference was significant only compared to group 2. It is concluded that the risk of calculus formation may increase following continuous and excessive intake of cocoa products in children with a tendency toward hypercalciuria. Counselling of the stone formers resulted in a marked drop of the daily oxalate excretion, and there was no recurrence of calculus formation over a period of 6 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Effect of allylisopropylacetamide and Sedormid on enzymes of steroid metabolism in rat liver.

Female rats, treated with allylisopropylacetamide (AIA) showed a marked decrease of hepatic NADH-5 alpha-reductase, NADPH-5 alpha-reductase, NAD+- and NADP+-3 alpha-hydroxysteroid dehydrogenase activities and an increase of the activity of NADH- and NADPH-5 beta-reductase and NAD+ and NADP+-3 beta-hydroxysteroid dehydrogenase. Administration of Sedormid decreased the activities of 5 alpha-reductases and 3 alpha-hydroxysteroid dehydrogenases (substrate, 5 alpha-dihydrotestosterone) and increased the activity of NADH-5 beta-reductase, whereas no effect was seen on NADPH-5 beta-reductase and 3 beta-hydroxysteroid dehydrogenase.

Acetamides↗

Effect of 5 alpha-dihydrocorticoids on enzymes of gluconeogenesis in rat liver.

5 alpha-Dihydrocortisol (11 beta, 17, 21-trihydroxy-5 alpha-pregnane-3,20-dione), 5 alpha-dihydrocorticosterone (11 beta, 21-dihydroxy-5 alpha-pregnane-3,20-dione) as well as cortisol (11 beta, 17, 21-trihydroxy-4-pregnene-3,20-dione) and corticosterone (11 beta, 21-dihydroxy-4-pregnene-3,20-dione) were administered for seven days to male rats. Blood glucose increased in cortisol- and corticosterone-treated rats and blood insulin decreased after 5 alpha-dihydrocorticosteroid treatment. In the liver, total protein was elevated after cortisol, corticosterone and 5 alpha-dihydrocorticosterone application. Phosphoenolpyruvate carboxykinase and fructose-1,6-diphosphatase activities in liver were significantly lowered after treatment with 5 alpha-dihydrocortisol and 5 alpha-dihydrocorticosterone.

Animals↗

Circadian rhythm of acid phosphatase activity in rat liver microsomes and dependence of NADH 5 alpha-reductase on phosphatase activity.

The specific activity of acid phosphatase in male and female rats follows a circadian rhythm. Preincubation of liver microsomes with testosterone led to an increase of phosphatase activity and a loss of circadian rhythm. NADH 5 alpha-reductase was inactivated by several animal and bacterial acid and alkaline phosphatases while the acid phosphatase from potatoes was ineffective. The extent of inhibition depends on the course of circadian rhythm of NADH 5 alpha-reductase activity. Preincubation of microsomes in the presence of testosterone inhibited the NADH 5 alpha-reduction of testosterone. No such inhibition was observed after preincubation of microsomes with progesterone.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗