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Biomedical subjects

U Heinrich

Publications and source records attributed to U Heinrich.

At least 91 records · Page 5Linked to original sources
PubMed1988

Preparative separation of human B and T lymphocytes by free flow electrophoresis.

An electrophoretic method for the quantitative separation of human B and T lymphocytes in a carrier-free system is presented. The method is based on the fact that B and T lymphocytes show marked overlap in their size and density characteristics, but differ sufficiently in surface charge to be separable by electrophoresis. The technique is performed in phosphate-buffered saline and appears to be especially suitable for the enrichment of nonstimulated, functionally intact lymphocytes which can be directly used for further immunological or biochemical studies.

B-Lymphocytes↗
PubMed1988

Urinary and faecal excretion of chrysene and chrysene metabolites by rats after oral, intraperitoneal, intratracheal or intrapulmonary application.

The urinary and faecal excretion of chrysene and its phenolic metabolites after oral, intraperitoneal, intratracheal, and intrapulmonary administration to rats have been studied by means of gas chromatography/mass spectrometry. The metabolite profile was found to depend on the mode of excretion and on the route of administration. In all cases the oxidation of chrysene in the 1,2- or 3,4-position predominates, whereas oxidation in the 5,6-position (K-region) seems be a minor pathway.

Administration, Inhalation↗
PubMed1988

Urinary excretion of aldosterone metabolite Kelly-M1 in patients with adrenal dysfunction.

Using tetrahydroaldosterone antibody a radioimmunoassay was developed to measure substance Kelly-M1 (K-M1) in human urine. The normal values were lower than observed by Kelly et al. who discovered the catabolite after giving large doses of exogenous aldosterone. While in essential hypertension the excretion of K-M1 was predominantly within the normal range, elevated values were found in most cases of 21-hydroxylase deficiency, both the simple virilizing and salt losing form, primary aldosteronism, renal hypertension and cystinosis. Our findings suggest that K-M1 may be formed from 21-deoxyaldosterone and/or by microbial intervention from aldosterone or its metabolites.

Adrenal Gland Diseases↗
PubMed1988

Improvement of growth and food utilization by human recombinant growth hormone in uremia.

We compared growth rate, food conversion ratio and morphology of the growth zone in female Sprague-Dawley rats with subtotal nephrectomy or sham operation. Both groups were either given vehicle or 1.4 IU/day recombinant human growth hormone (GH) by s.c. osmotic minipump, or 2.5 IU twice daily intraperitoneally for 14 or 20 days, respectively. Compared to uremic rats infused with vehicle, infusion of GH significantly (P less than 0.01) improved growth; that is, it increased gain of weight (delta 27.0 +/- 7.7 g vs. 11.6 +/- 4.9 g) and length (delta 1.8 +/- 0.3 cm vs. 1.12 +/- 0.44 cm) in ad libitum fed uremic rats. This was accompanied by increased food utilization ratio (0.146 vs. 0.065 g weight gain per g food intake). A similar increment of growth and food utilization ratio was also observed in GH versus solvent infused controls, either pairfed as for the uremic animals or fed ad libitum. Despite administration of GH, growth was not completely restored to normal in uremic animals. Circulating immunoreactive IGF I was not significantly increased by GH infusion in either uremic animals or controls. Histological analyses of the proximal tibia showed increased rate of longitudinal growth, as evaluated by tetracyclin-labeling, and increased volumetric density of primary spongiosa with unchanged width of primary spongiosa trabecules when GH was infused in uremic animals. The data suggest that growth impairment in the uremic rat is partially responsive to GH, and this is not accompanied by an increase of circulating IGF I. Therapeutic trials with recombinant GH in uremic children appear justified.

Animal Nutritional Physiological Phenomena↗
PubMed1987

Quantitative evaluation of optical reflection spectra of blood-free perfused guinea pig brain using a nonlinear multicomponent analysis.

After developing a blood-free perfused preparation of the guinea pig brain a nonlinear multicomponent analysis (NLMCA) of the reflection spectra of the brain surface was worked out by which the redox state of cytochrome aa3, c, and b could be evaluated quantitatively and almost continuously. The NLMCA allowed to simulate the tissue reflection spectra in such a way that only a small statistical error remained between the recorded and the computed spectra. Using redox states of cytochrome aa3 and c as an intracellular oxygen probe it was found that in order to supply the guinea brain with sufficient oxygen by a saline medium equilibrated with 95% oxygen and 5% CO2 the temperature had to be reduced to 18-20 degrees C. At this temperature cytochrome aa3 was 95% oxidized.

Animals↗
PubMed1987

Clitoromegaly and abdominal tumour as leading signs of a mediastinal non-Hodgkin lymphoma.

A 2-year-old girl was admitted with clitoromegaly, mediastinal tumour and enlarged kidneys. A seventh cranial nerve palsy was associated with an increased cell count in cerebrospinal fluid. The diagnosis of a lymphoblastic lymphoma was confirmed by a cervical lymph-node biopsy. Six years after diagnosis and treatment according to the BFM protocol the girl remains in first complete remission.

Abdominal Neoplasms↗
PubMed1987

Atrial natriuretic peptide in infants and children.

Atrial natriuretic peptide (ANP) was measured in the plasma of 192 normal infants and children aged 1 day to 18 years. Plasma ANP was high during postnatal adaptation, particularly in premature infants. In 96 infants and children aged 4 months to 18 years, plasma ANP was similar to values obtained in 7 healthy adult volunteers (23.9 +/- 11.9 vs. 25.7 +/- 4.6 fmol/ml). There was no significant relationship between ANP and age. ANP is elevated about twofold in full-term neonates being 3-4 days of age, and returned to normal thereafter. It is concluded that ANP is raised during the postnatal adaptation. This hormone is possibly involved in the postnatal volume contraction and may antagonize vasoconstrictor hormones that are elevated during the postnatal period.

Adolescent↗
PubMed1987

21-Deoxyaldosterone excretion in patients with primary aldosteronism and 21-hydroxylase deficiency.

21-Deoxyaldosterone appears in urine in free and conjugated forms. Total excretion is best determined after acid hydrolysis (pH 1) of urine, followed by extraction, repeated chromatographic purification, and quantitation of the steroid by RIA. 21-Deoxyaldosterone excretion was normal in 70% of patients with essential hypertension (n = 18), while 30% (n = 8) had more or less elevated values. In patients with primary aldosteronism (n = 21) elevated as well as normal values of urinary 21-deoxyaldosterone were found, indicating that in some patients aldosterone may be formed not only from corticosterone but also from the 21-deoxy compound. In patients with 21-hydroxylase deficiency (n = 21) urinary 21-deoxyaldosterone was invariably elevated, whether the patients had the virilizing or salt-losing form of the disease. Although the clinical manifestations of the salt-losing form seem unrelated to the inability to convert 21-deoxyaldosterone to aldosterone, the determination of 21-deoxyaldosterone adds insight into the biosynthesis of aldosterone in primary aldosteronism and 21-hydroxylase deficiency.

Adolescent↗
PubMed1986

Chronic effects on the respiratory tract of hamsters, mice and rats after long-term inhalation of high concentrations of filtered and unfiltered diesel engine emissions.

A long-term exposure study with hamsters, mice and rats inhaling filtered and unfiltered diesel engine exhaust was carried out to investigate effects of chronic toxicity and, predominantly, carcinogenicity in the respiratory tract. The level of diesel exhaust in the exposure chambers corresponded to a concentration close to 4 mg m-3 in the unfiltered diesel exhaust. Satellite groups of animals were additionally treated with BaP, DBahA or nitrosamines in order to check for syncarcinogenic effects. In hamsters and rats, alveolar lung clearance and mechanical lung function tests as well as biochemical and cytological measurements in lung lavage fluids showed significant changes only after exposure to unfiltered diesel exhaust and, predominantly, in rats. No lung tumors were found in hamsters. Spontaneous tumor rates occurred in mice and both types of diesel exhaust increased the incidence of adenocarcinomas in the lungs. In rats, only the unfiltered diesel exhaust caused a lung tumor incidence. It amounted to 16% with no tumors in the controls. The heavy load of particulate matter in the lungs of rats was caused by an exposure-related impairment of the alveolar lung clearance and may have been instrumental in the induction of squamous cell tumors. However, an effect of particle-associated PAH cannot be excluded. Syncarcinogenic effects of diesel exhaust after initial carcinogen treatment were found only in the respiratory tract of rats.

Animals↗
PubMed1986

Radioimmunoassay of urinary 21-deoxytetrahydroaldosterone in primary aldosteronism and 21-hydroxylase deficiency.

A radioimmunoassay of 21-deoxytetrahydroaldosterone was developed. Normal daily excretion of the unconjugated metabolite was 1.2 +/- 1.3 micrograms and of the glucuronized metabolite, 11.9 +/- 7 micrograms. The tetrahydroaldosterone/21-deoxytetrahydroaldosterone ratio varied more in patients with primary aldosteronism than in control subjects. Thus, measurements of the urinary excretion of the tetrahydroaldosterone or 21-deoxytetrahydroaldosterone alone did not provide an accurate expression for aldosterone production. Their sum correlated well with the clinical condition, i.e. clear-cut elevation in patients with primary aldosteronism. The diminished tetrahydroaldosterone/21-deoxytetrahydroaldosterone ratio found in patients with 21-hydroxylase deficiency may be attributed to increased bacterial conversion of tetrahydroaldosterone to 21-deoxytetrahydroaldosterone but could also stem from a deficiency implicating zona glomerulosa (aldosterone biosynthesis) regardless of the stage and clinical presentation of the disease.

Adrenal Hyperplasia, Congenital↗
PubMed1986

Lung tumours in rats and mice after inhalation of PAH-rich emissions.

Rats and mice were exposed to a PAH-rich emission to test the carcinogenic activity. The BaP content of the exposure atmosphere was only 2-3 times higher than the concentration of about 30 micrograms/m3 measured in older coke plants. Although only half of the rats exposed to the exhaust have been investigated histologically up to now, the lung cancer incidence already amounts to 11%, no lung tumours were found in the control animals. Also the mice exposed to the exhaust with and without additional treatment with BaP, DBahA or urethane to induce a "base tumour rate" in the lung, showed a clear exhaust exposure-related carcinogenic effect. The lung tumour multiplicity as well as the incidence was significantly higher. The epidemiological findings of an increased lung cancer risk in coke oven workers can now be supported by the results of this animal inhalation study.

Air Pollutants↗
PubMed1986

Effects of methotrexate on rabbit testes. Part 1: Morphological changes.

Methotrexate (MTX) has the potential of eradicating small infiltrations of leukemic cells in the gonads. We examined the morphological changes in rabbit testes after a single dose (57.5 mg/kgBW) or repeated low doses (6 mg/kgBW once a week for 14 weeks) of MTX IV. Fertility rate and spermatogenic activity were evaluated using the tubular fertility index (TFI). Testicular MTX concentrations (measured by RIA) were in the same range in both groups. Only after repeated MTX application were reduction of TFI and signs of germinal cell line degeneration found. When given repetitively, MTX therapy may modify the fertility and tubular morphology. Long-term follow-up will show how these changes affect future fertility.

Animals↗
PubMed1986

Effects of methotrexate on rabbit testes. Part 2: Hormonal changes.

Thirty mature and peripubertal male rabbits were examined for endocrine function and tissue methotrexate (MTX) concentration after single (57.5 mg/kgBW, group 1) and repeated (6 mg/kgBW, once a week for 14 weeks, group 2) MTX doses. Follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone, and androstenedione plasma levels were measured by radioimmunoassay (RIA). We found elevated plasma FSH levels in both groups. Elevated plasma androstenedione level and reduced plasma testosterone level in group 2 suggest an enzymatic defect in the gonadal steroid synthesis. Unchanged LH plasma level, when compared to controls, is thought to be the result of a combined effect of MTX on the gonadal steroids and gonadotropin synthesis.

Androstenedione↗