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H Hebestreit

Publications and source records attributed to H Hebestreit.

27 records · Page 2Linked to original sources
PubMed1996

Expression and function of the Fas receptor on human blood and tissue eosinophils.

The interaction between activated T cells and eosinophils has been proposed to play an important role in the pathogenesis of allergic diseases. T cell-derived cytokines such as interleukin-5 and granulocyte/macrophage colony-stimulating factor inhibit eosinophil apoptosis and may therefore contribute to the development of tissue and blood eosinophilia in these disorders. Withdrawal of these cytokines leads to eosinophil apoptosis in vitro. In contrast, the mechanisms which actively induce apoptosis in eosinophils are at present not completely understood. In this study, we demonstrate that freshly isolated human eosinophils express mRNA and protein for the Fas receptor. Using anti-Fas monoclonal antibody (mAb), we show that Fas activation accelerates apoptotic eosinophil death in vitro. Moreover, treatment of nasal polyps ex vivo with anti-Fas mAb decreased eosinophilic tissue inflammation. However, we observed that blood as well as tissue eosinophils derived from some eosinophilic donors do not express functional Fas receptors, although Fas protein is normally expressed in these cells. This implies that the susceptibility of the Fas receptor is a matter of regulation in eosinophils as previously observed in other systems. These data suggest that Fas ligand/Fas interactions are involved in the regulation of eosinophil apoptosis and that defects in this system could contribute to the accumulation of these cells in allergic and asthmatic diseases.

Antibodies, Monoclonal↗
PubMed1996

Plasma metabolites, volume and electrolytes following 30-s high-intensity exercise in boys and men.

It has been shown that boys recover faster than men following brief, high-intensity exercise. Better to understand this difference, plasma metabolite concentration, volume, electrolyte concentration [electrolyte], and hydrogen ion concentration [H+] changes were compared in five prepubescent boys [mean age 9.6 (SD 0.9) years] and 5 men [mean age 24.9 (SD 4.3) years] following 30-s, all-out cycling. Blood was collected prior to, at the end, and at the 1st, 3rd and 10th min following exercise. At the 10th min of recovery, the men's lactate concentration was 14.2 (SD 1.8) mmol.l-1 and [H+] was 66.1 (SD 5.9) nmol.l-1, compared with 5.7 (SD 0.7) mmol.l-1 and 47.5 (SD 1.2) nmol.l-1 respectively, in the boys (P < 0.01 for both). The glycerol concentration was higher in the boys at the end of exercise and until the 3rd min of recovery. Plasma volume (PV) decreased more in the men [16.9 (SD 3.0)%] than in the boys [9.4 (SD 2.8)%]. In both groups, [electrolyte] increased after exercise, tending to be higher in the men. Recovery of plasma [electrolyte] and PV started earlier in the boys (1st min) than in the men (3rd min). These findings would support the notion of a lesser reliance on glycolytic energy pathways in children and may explain the faster recovery of muscle power in boys compared to men.

Adult↗
PubMed1996

Isolated dihydroxyacetonephosphate-acyl-transferase deficiency in rhizomelic chondrodysplasia punctata: clinical presentation, metabolic and histological findings.

UNLABELLED: Rhizomelic chondrodysplasia punctata (RCDP) is clinically characterized by symmetrical shortening of the proximal limbs, contractures of joints, a characteristic dysmorphic face, and cataracts. In the classical form an impairment of several peroxisomal functions and enzymes (plasmalogen synthesis, phytanic acid oxidation, 3-oxoacyl-CoA thiolase) has been repeatedly shown. Recently a variant involving only the peroxisomal dihydroxyacetonephosphate acyltransferase (DHAP-AT) has been described. We present a patient with isolated DHAP-AT deficiency and all clinical, radiological and pathological features of classical RCDP. For the first time, microscopy and immunocytochemistry of hepatocytes could be performed. CONCLUSION: In contrast to studies on classical rhizomelic chondrodysplasia punctata which have shown enlarged peroxisomes in numbers varying from hepatocyte to hepatocyte, the peroxisomes in our patient seem to be normal in size, number and shape.

Acyltransferases↗
PubMed1995

Climate-related corrections for improved estimation of energy expenditure from heart rate in children.

The purpose of this study was to determine the relationship between children's heart rate (HR) and climatic heat stress at several O2 uptake (Vo2) levels and to construct equations and nomograms for an improved estimation of energy expenditure (EE) from HR monitoring. On four occasions 12 boys and 8 girls (8-11 yr) cycled for 5 min each at 35, 55, and 75% of peak Vo2 (random order), with rest periods in between, in a climatic chamber. The randomly assigned conditions were 22 degrees C dry bulb temperature, 50% relative humidity (RH); 28 degrees C, 55% RH; 32 degrees C, 52% RH; or 35 degrees C, 58% RH. HR and Vo2 were determined during the final 2 min of rest and exercise bouts. HR measured at a dry bulb temperature (T) (HRmeas) was then related to a HR at 22 degrees C that would have been expected to occur at an identical Vo2 (HRcalc22) by using individual 22 degrees C HR-Vo2 regression lines. HRcalc22 could be estimated from HRmeas.[1.175032-(0.007956.T)], with a mean error of prediction for the entire group < 1.5 beats/min for each temperature. The following conclusions were drawn: 1) children's HR at a given Vo2 increases linearly with ambient temperature at 22-35 degrees C, 50-60% RH; and 2) HR can be corrected for the influence of climate in groups of children resting and exercising at the above conditions, thereby reducing the error of estimating EE from HR.

Child↗
PubMed1993

Muscle performance and gross motor function of children with spastic cerebral palsy.

The purpose of this study was to determine whether, and to what extent, performance on a measure of motor function (Gross Motor Function Measure, GMFM) was related to the physiological fitness of children with cerebral palsy (CP). Two elements of physiological function were measured: aerobic power and anaerobic power of the arms and legs. 15 boys and eight girls aged between seven and 13.9 years with spastic CP participated in the study. There was a good relationship between the standing and walking, running and jumping sub-sections and the total score of the GMFM on one hand, and anaerobic capacity of the legs on the other. However, the relationships for the arms were limited, indicating that the GMFM is not a suitable tool for providing information about aerobic fitness in children with CP, or about anaerobic power of the arms.

Adolescent↗
PubMed1993

Recovery of muscle power after high-intensity short-term exercise: comparing boys and men.

This study was conducted to determine whether boys differ from men in their ability to recover from high-intensity exercise. Two groups of volunteers, 8 prepubertal boys (9-12 yr) and 8 young men (19-23 yr), were similar in their peak oxygen uptake (49.6 +/- 6.6 vs. 51.1 +/- 6.6 ml.min-1 x kg-1), adiposity, and activity levels. On three different occasions subjects performed two consecutive 30-s all-out cycling tasks [Wingate anaerobic test (WAnT)], separated by a 1-, 2-, or 10-min recovery interval. In the boys, mean power reached 89.9 +/- 3.6% of the initial value after 1 min of recovery, 96.4 +/- 2.3% after 2 min, and 103.5 +/- 1.3% after 10 min. For the men, the values were 71.2 +/- 2.6, 77.1 +/- 2.4, and 94.0 +/- 1.3%, respectively (boys vs. men, P < 0.0001). Relative to the external work performed during the first WAnT, the boys had a higher net oxygen uptake (exercise--resting) during the test than the men (83.8 +/- 18.4 vs. 57.8 +/- 6.1 ml/kJ). After the WAnT, the net CO2 output and the respiratory exchange ratio were lower in the boys, and they recovered faster. It was concluded that boys recover faster than men from high-intensity short-term exercise. This may reflect a lower reliance on glycolysis during the WAnT in the boys, leading to less acidosis. It is also possible that the boys had a faster postexercise removal of metabolites.

Adult↗
PubMed1992

Anaerobic endurance and peak muscle power in children with spastic cerebral palsy.

The aim of this study was to provide information on anaerobic muscle endurance (mean power) and peak muscle power in children with spastic cerebral palsy. We measured peak power and mean power of the upper and lower limbs in 29 boys and 20 girls, aged from 6 to 14 years, by means of the Wingate Anaerobic Test. In addition, the physical components (physical capacity, upper limb, and lower limb) of a system used for evaluating function in the physically disabled were assessed. Of the 49 subjects, 46 and 37 successfully completed the arm and leg Wingate Anaerobic Test, respectively. Compared with norms for age and gender (healthy, nonathletic children), peak and mean power in the patients, even when corrected for body weight, were distinctly subnormal. The performance of subjects with quadriplegia was 3 to 4 SDs below the mean for controls. Twenty-five of diplegic and hemiplegic subjects had values below 2 SDs. When the data were analyzed according to the severity of the cerebral palsy, with the use of the physical capacity, upper limb, and lower limb score, those children with moderate to severe cerebral palsy had values for mean and peak power of the arm and leg 3 to 4 SDs below the normal mean. Values for children with only mild cerebral palsy also fell below the mean, but the data were more scattered, especially for the leg. The lower muscle performance may reflect both quantitative and qualitative differences in the upper- and lower-limb muscles, due to altered innervation and, in the more severely affected children, disuse.

Adolescent↗
PubMed1990

[Pellagra in anticonvulsive therapy].

The case of a mentally handicapped female patient is presented who developed typical pellagra with dermatitis, diarrhoea and mental alteration following a long-term antiepileptic treatment with phenytoin, ethosuximide and valproic acid. In addition, she had a deficient meat intake. A course of treatment with multivitamins proved successful in resolving the symptoms within 2 weeks.

Adult↗