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H J Müller

Publications and source records attributed to H J Müller.

At least 109 records · Page 6Linked to original sources

Membrane solubility of chlorpromazine. Hygroscopic desorption and centrifugation methods yield comparable results.

Binding of the positively charged drug chlorpromazine to artificial and erythrocyte bilayer membranes was investigated by the filtration method called hygroscopic desorption [Conrad & Singer (1979) Proc. Natl. Acad. Sci. U.S.A. 76, 5202-5206] and by the conventional centrifugation method. Only minor differences in the partition coefficients were observed using the two methods. Our finding is not consistent with the observation of Conrad & Singer that amphipaths are completely excluded from biological membranes. However, the partition coefficient is dependent on membrane composition, which means dependent on the physical properties of a membrane.

Cell Membrane↗

Major histocompatibility complex of the mole-rat. I. Serological and biochemical analysis.

The mole-rat, Spalax ehrenbergi, is a complex subterranean rodent species whose habitat is restricted largely to the Middle East and North Africa. We typed over 50 mole-rats with mouse monoclonal and polyclonal antibodies specific for class I and class II major histocompatibility complex (Mhc) molecules. Some of these antibodies were produced against mouse Mhc molecules, others against Mhc molecules of other species. About 25% of the antibodies reacted with mole-rat lymphocytes in the cytotoxic test. Some of the serologically positive antibodies precipitated from a glycoprotein pool of mole-rat spleen cell molecules that corresponded in size with class I and class II molecules of other species. We conclude, therefore, that mole-rats, like other mammals, possess the Mhc which consists of class I and class II loci. We call this Mhc Spalax major histocompatibility (Smh) complex. The occurrence of a large number of different serotypes among the tested animals suggests that Smh loci are polymorphic. This Mhc polymorphism of the mole-rat contrasts with the monomorphism or oligomorphism of the Syrian hamster, a rodent with a similar ecology. Thus far no qualitative correlation could be found between Smh polymorphism and chromosome variation described in this superspecies.

Animals↗

[Esophageal cancer].

Surgery of oesophageal cancer has a high risk demonstrated by the hospital lethality. 72 resections of the oesophagus done by one surgeon are analysed. The following parameters were used: 1) a nutritional index developed in carcinoma patients in a prospective analysis, 2) the EKG result, 3) the lung-function. Adding these 3 indices we get a certain correlation between the judgement of the preoperative risk and hospital lethality. The preoperative criteria of risk are essential for patients with cancer of the oesophagus since we have to choose among 3 groups of surgical treatment, the risks of which are significantly different.

Electrocardiography↗

[The somatostatin infusion test for the evaluation of glucose utilization in bezafibrate medication].

The utilisation of blood glucose may be used for definition of insulin resistance in type II diabetes mellitus. To evaluate this possibility we adapted an infusion test of somatostatin in 10 normal persons (age 26 +/- 3 years, relative body weight 26 +/- 10% according to Broca) in a randomized cross-over therapy with bezafibrate (3 X 200 mg/die). As the coefficient of variation (VC) of measured blood glucose continuously increased the best time of a steady state was between 90 and 130 min after beginning the infusion (mean VC 8.9%). While insulin remained nearly constant (41 (45; 38) microU/ml) blood glucose dropped by about 14% and reached a steady state of 89 (134; 45) mg/dl. During the therapy of bezafibrate blood glucose was significantly decreased by 36% 130 min after beginning the infusion. Although the effect was not significant during the whole time of the steady state it became evident by a negative correlation with lactate (r = -0.687) and pyruvate (r = -0.843). A correlation with a concomitant decrease of triglyceride and cholesterol also induced by bezafibrate could not be proven. The results show that the infusion test of somatostatin is fitted to measure a steady state of blood glucose and insulin and that it is possible by this technique to quantify a changed utilisation of blood glucose induced by specific therapy.

Adult↗

Pressure variation of the lateral diffusion in lipid bilayer membranes.

A pressure-induced decrease of the lateral diffusion in pure and cholesterol containing phosphatidylcholine bilayer membranes has been determined by the excimer formation technique using pyrene as probe molecule. The experimental results at pressures up to 150 bars are described satisfactorily by the free volume theory of a molecular transport in liquids. A pressure increase of extrapolated 575 bars decreases the lateral diffusion of lipids by a factor of two in pure dipalmitoylphosphatidylcholine membranes. Higher pressures are necessary to induce the same effect in cholesterol containing membranes. This result is interpreted by the condensing effect of cholesterol in fluid bilayer membranes.

Cholesterol↗

[Antagonistic effects of glucocorticoids and aristolochic acid on the immunocyte adherence phenomenon (author's transl)].

The influence of prednisolone and 3,4-methylenedioxy-8-methoxy-10-nitrophenanthrenecarbonic acid-1 (aristolochic acid) on the immunocyte adherence phenomenon in the rat was investigated. The following results were obtained: Prednisolone diminishes the number of rosettes. Aristolochic acid itself has no influence on the number of rosettes but compensates the diminuation caused by prednisolone. Equal effects were found for 5 mg/kg b.w. prednisolone and 0.005 mg/kg aristolochic acid. This effect of aristolochic acid is interpreted as competitive inhibition of surface receptors of lymphocytes.

Animals↗

Pathological cell aggregates in bone marrow cultures from patients with various hematological diseases.

Non-clonal growth of macroscopic cell aggregates in methylcellulose cultures of abnormal marrow is described. They were seen in all patients with Graft-versus-Host Disease, graft rejection, and autoimmune disease presumably directed against hemopoietic cells, we found them in 35% of patients with primary hematological neoplasias and rarely in patients with solid tumors. They were never encountered in 80 healthy controls. The aggregates originated from small cell clumps which sedimented with the "buffy coat" in contrast to normal bone marrow particles. They contained tumor cells, grafted myeloid cells, or target cells of autoimmune disease in association with a widely varying amount of macrophages. Preliminary results suggest that the frequency of macrophages within the aggregates correlates inversely with the aggressiveness of the clinical condition. We propose that appearance of such aggregates in an indicator of immune activation; we expect that further quantitation of the phenomenon will reveal important clinical correlations and provide a model for the study of host defense to "foreign" cells.

Anemia, Hemolytic, Autoimmune↗

[Betaglucuronidase activity in ovarian carcinoma (author's transl)].

Beta-glucuronidase activity was recorded from the tissue of 45 ovarian carcinomas and compared to the activity in normal human ovarian tissue. Mean activities were 1442 micrograms Ph./h/g tissue in ovarian carcinomas and 574 micrograms Ph./h/g in intact ovarian tissue. No relationship was found to exist between the amount of beta-glucuronidase activity and the stage of the disease.

Adult↗

Loss of the Y chromosome from bone marrow cells of males with myeloproliferative disorders. Report of two cases and review of the literature.

Two additional cases of myeloproliferative disorders are described showing as the only chromosome abnormality a loss of the Y chromosome. Comparing these cases with cases reviewed from the literature indicates that a loss of the Y chromosome in Ph1-positive and Ph1-negative CML may cause only a somewhat longer life expectancy following diagnosis. The exact role of the Y chromosome, however, in the initiation or progression of a malignant disorder cannot be stated at this time.

Adult↗

[Beta-glucuronidase activity in human ovarian tissue during the life- and cycle-phases of the woman].

The behaviour of the beta-glucuronidase activity during the life phases and the phase of the cycle of a woman has been studied in 51 human ovaries after the Dohrmann method. The study clearly indicates a dependency on age, that is demonstrated by a rise in beta-glucuronidase activity from 536 microgram Ph/h/g ovarial tissue during full functioning to 705 microgram Ph/h/g ovarial tissue in the premenopause and by dropping to 529 microgram Ph/h/g ovarial tissue in the menopause and the senium. The premenopause values are significantly higher compared to that of the other two functional phases. The activity of the beta-glucuronidase is significantly higher in the secretory phase than in the proliferation phase. Existing relations between the beta-glucuronidase of the ovary and the gonadotropic hormones of the hypophysis and the oestrogen metabolism are discussed.

Adult↗

A simple fluorescence staining technique for the differentiation of human tissue transplanted into nude mice.

Human and mouse nuclei can be distinguished by differences in the constitutive heterochromatin when stained with quinacrine dihydrochloride. With the staining method described, mouse heterochromatin during interphase appears as brilliant fluorescent chromocenters. By replacing the commonly used aqueous buffer mounting medium with a xylene-diluted synthetic resin, the haziness of the nuclear fluorescence is eliminated thus allowing identification of the heterochromatin pattern in histological preparations. A requirement for the definite identification of cells of human or murine origin in the nude mouse is the knowledge that the heterochromatin arrangements changes according to the stage of differentiation of the cell of the position of a particular nucleus within the cell cycle.

Animals↗