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C Hübner

Publications and source records attributed to C Hübner.

81 records · Page 5Linked to original sources
PubMed1989

A membrane fluidizing factor in sera from Duchenne muscular dystrophy patients: effect on lymphocyte membranes of incubation in patient and control lipoproteins.

Sera from Duchenne muscular dystrophy (DMD) patients showed a membrane fluidizing effect on DMD and control lymphocytes. To look for the cause of this membrane fluidizing effect, human lymphocytes from healthy subjects were incubated in sera and in different serum fractions from DMD patients and healthy control subjects, and membrane fluidity was determined by steady state fluorescence polarization of the probe diphenyl hexatriene. DMD sera and total DMD lipoproteins showed a similar membrane fluidizing effect (p less than 0.02) after incubation, whereas lipoprotein deficient serum did not show any effect on membrane fluidity. Control and DMD HDL showed a membrane fluidizing effect, the fluidizing effect of DMD HDL being slightly higher as compared to control HDL. Control LDL and DMD LDL showed a membrane rigidifying effect, the rigidifying effect of DMD LDL being significantly lower as compared to control LDL (p less than 0.02). These data demonstrate that the membrane fluidizing effect of DMD serum is lipoprotein associated, LDL being the most important mediator of this effect.

Adolescent↗
PubMed1988

Membrane fluidity and lipid composition of rat small intestinal brush-border membranes during postnatal maturation.

Fluidity and lipid composition of rat small intestinal brush-border membranes (BBM) were studied during maturation in five age groups: newborns, sucklings (1-3 weeks), weaned (4-6 weeks), juveniles (8-10 weeks), and adults (12 weeks). Brush-border membrane fluidity was measured by steady-state fluorescence polarization. Fluorescent probes used were: 1,6-diphenyl-1,3,5-hexatriene, 1-(4-trimethylammonium)phenyl)-6-phenyl-1,3,5-hexatriene, and a set of n-(9-anthroyloxy) fatty acids. Fluorescence anisotropy measured with all fluorophores was increased in adult versus newborn rats (P less than 0.004). The weight ratio of saturated to cis-unsaturated fatty acids increased from birth to the suckling age (P less than 0.0004). The cholesterol to phospholipid molar ratio increased from birth to the weaned age (P less than 0.0001). Cholesterol to protein ratio and phospholipid to protein ratio decreased after the weaned age (P less than 0.004). The results not only describe maturational changes of brush-border membranes but also give a better understanding of the correlations between biophysical and biochemical data in biological membranes.

Animals↗
PubMed1988

Decreased membrane fluidity of lymphocytes from patients with juvenile neuronal ceroid-lipofuscinosis.

The storage material in neuronal ceroid-lipofuscinoses (NCL) apparently contains breakdown products of membrane lipids. The storage could be due to an unknown enzyme deficiency in the degradation of lipids or to an alteration of the lipid substrate within the plasma membrane. We investigated the membrane fluidity of intact lymphocytes in juvenile NCL (McKusick no. 20420) by steady-state fluorescence polarization. Fluorescent probes used were diphenylhexatriene (DPH), trimethylammonium-DPH (TMA-DPH), and a set of n-(9-anthroyloxy) fatty acids. Membrane fluidity was decreased in NCl (n = 12) vs. control lymphocytes when measured with the labels DPH, TMA-DPH, 6-, 7-(9-anthroyloxy) stearic acid, and 16- (9-anthroyloxy) palmitic acid (P less than 0.05). In order to check for the influence of anticonvulsants on membrane fluidity, we investigated 17 epileptic patients (without NCL) treated with anticonvulsants. Membrane fluidity was increased in these patients when measured with DPH and with the anthroyloxy probes. Our results indicate a decreased fluidity of the outer membrane leaflet in NCL lymphocytes which is independent of the effect of anticonvulsants.

Adolescent↗
PubMed1988

CT scans and neuroleptic response in schizophrenia: a multidimensional approach.

Structural brain abnormalities in schizophrenia have been reported in a number of studies using computed tomography (CT). However, the prevalence and the localization of the abnormalities vary widely among studies. These discrepancies might stem from clinical and demographic differences among samples, from the choice of the CT parameters, or from the use of different criteria to define abnormalities. In an attempt to overcome these difficulties, we studied 12 CT parameters in 30 schizophrenic patients and 30 sex- and age-matched controls, and evaluated the data simultaneously through multidimensional scaling (MDS). MDS offers a graphic representation in which subtle deviations in the different CT parameters can be detected, independently of predetermined criteria for the definition of abnormalities. MDS distinguished 13 patients from the controls as having deviant values in one or more CT parameters. Five of these patients were first-onset schizophrenics. Patients with deviant CT parameters showed significantly poorer response to haloperidol therapy over 3 weeks than did patients without deviant CT parameters. Our results suggest that the MDS approach might be useful in identifying more precisely patients with and without structural brain abnormalities.

Adult↗
PubMed1987

Membrane fluidity of nonmuscle cells in Duchenne muscular dystrophy: effect on lymphocyte membranes of incubation in patient and control sera.

The membrane fluidity of intact fibroblasts, erythrocyte ghosts, and intact lymphocytes from Duchenne muscular dystrophy (DMD) patients and controls was measured by steady state fluorescence polarization. The fluorescent probes used were diphenylhexatriene (DPH), trimethylammonium-DPH, and a set of n-(9-anthroyloxy) fatty acids. Fluorescence anisotropies in DMD fibroblasts and DMD erythrocyte ghosts were normal. In DMD lymphocytes (n = 10) fluorescence anisotropy of DPH was decreased versus controls (0.212 +/- 0.028 versus 0.231 +/- 0.012, p less than 0.05). Linear regression analysis of creatine kinase activity in sera and DPH fluorescence anisotropy in lymphocytes from DMD patients showed a negative correlation (r = -0.93, p less than 0.001). DMD lymphocytes and control lymphocytes were incubated for 4 h in sera from DMD patients and from controls. When incubated in DMD sera, DPH fluorescence anisotropy of DMD lymphocytes decreased from 0.211 +/- 0.018 to 0.180 +/- 0.028, and fluorescence anisotropy of control lymphocytes decreased from 0.239 +/- 0.012 to 0.179 +/- 0.025 reaching the same level as did DMD lymphocytes. When incubated in control sera, DPH fluorescence anisotropy of DMD lymphocytes increased to 0.224 +/- 0.012, and fluorescence anisotropy of control lymphocytes decreased to 0.218 +/- 0.017. The fluorescence anisotropy changes after incubation in DMD versus control sera were different (p less than 0.05 for DMD lymphocytes and p less than 0.005 for control cells). Our findings do not support the hypothesis of a general membrane defect but suggest a toxic serum factor in DMD which attacks lymphocyte membranes and possibly muscle membranes at the same time.

Adolescent↗
PubMed1983

Bullectomy.

The aims of this study were to investigate whether a relevant functional improvement before and after bullectomy was achieved in cases of a localized bulla and generalized bullous changes early and late postoperatively and to establish clear criteria for bullectomy. For this purpose, 21 patients with a localized bulla compressing the rest of the lung, and 19 with generalized bullae with emphysematous changes of the remaining lung were examined before and after (1 1/2 months and 1 1/2 years) surgery. Comparison of the preoperative and postoperative data and the follow-up included X-ray studies with planimetric assessment of the size of the bullae, lung function tests, perfusion scintigrams and clinical findings. The preoperative and postoperative statistical values of lung volume and respiratory mechanics showed the most significant differences. Bullectomy for a localized bulla with compression of the rest of the lung led to an improvement in gas exchange and respiratory mechanics. This operation, however, produced no functional improvement in cases of generalized bullous changes. Functional and clinical success is greater, the larger and more delimited the bulla is to be seen on X-ray, the more the healthy lung tissue is compressed, and, finally, the less associated diseases such as chronic bronchitis are present. Indication for bullectomy should be limited to these cases. The size of the bulla should amount to at least 2/3 of the hemithorax, preoperative function should be clearly reduced and the patient should be suffering from dyspnea.

Follow-Up Studies↗
PubMed1982

[Sonographic findings in malignant lymphoblastic T-cell lymphomas in childhood].

Lymphoblastic T-cell lymphoma is the most frequent Non-Hodgkin's lymphoma in childhood. The generalized character of this malignancy in patients without early leukemic conversion can often be shown by ultrasonography. Sonography can be performed even in the dangerously ill patients without disturbance. Beside the intraabdominal extension the consequences of the mediastinal tumor, pericardial and pleural effusions can be demonstrated. We report our findings in 6 patients with lymphoblastic T-cell lymphoma without early leukemic conversion.

Adolescent↗