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991.
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In the human central nervous system, progesterone is rapidly metabolised to 5 alpha-dihydroprogesterone which subsequently is further reduced to allopregnanolone (AP). These conversions are catalysed by 5 alpha-reductase and 3 alpha-hydroxysteroid dehydrogenase (3 alpha-HSD). Although different isoforms of both enzymes have been identified in the brain, our knowledge of their expression in the human brain remains limited. The aim of the present study was to investigate the mRNA expression of 5 alpha-reductase 1 as well as 3 alpha-HSD 1, 2, 3 and 20 alpha-HSD in brain tissue from patients with pharmacoresistant temporal lobe epilepsy (TLE). Specimens were derived from either the hippocampus or the temporal lobe cortex and from the tumor-free approach corridor tissue of patients with brain tumors. Quantification of different mRNAs was achieved by real time PCR. In addition, we provide data on simultaneous evaluation of serum AP concentrations. We could demonstrate that 3 alpha-HSD 1 was not expressed in the hippocampus and temporal lobe of patients with TLE. In the hippocampus and temporal lobe, the expression levels of 3 alpha-HSD 2 were about 20% of that in liver tissue, those of 3 alpha-HSD 3 about 7% and those of 20 alpha-HSD about 2%, respectively. In patients with TLE, expression of 3 alpha-HSD 2 was significantly higher in the hippocampus than in temporal lobe cortex tissue (P<0.006). AP concentrations did not correlate significantly with the mRNA expression levels of 5 alpha-reductase 1, 3 alpha-HSD 2 and 3 and 20 alpha-HSD in any of the patient groups under investigation. In conclusion, the present study demonstrates mRNA expression of 5 alpha-reductase 1 and 3 alpha-HSD 2 and 3 and 20 alpha-HSD in the hippocampus and temporal lobe of epileptic patients. These findings provide further molecular biological evidence for the formation and metabolism of neuroactive steroids in the human brain.  相似文献   
993.
We report the clinical, genetic and cardiac magnetic resonance imaging (MRI) findings in 11 German patients with heterozygous E245D, D339Y, R350P and L377P desmin mutations and without cardiac symptoms. Clinical evaluation revealed a marked variability of skeletal muscle, respiratory and cardiac involvement even between patients with identical mutations, ranging from asymptomatic to severely affected. While echocardiography did not show any pathological findings in all 11 patients, cine MRI revealed focal left ventricular hypertrophy in 2 patients and MR delayed enhancement imaging displayed intramyocardial fibrosis in the left ventricle in 4 patients indicating early myocardial involvement. Our data argue against distinct genotype-phenotype correlations and suggest that comprehensive cardiac MRI is superior to conventional echocardiography for the detection of early and clinically asymptomatic stages of cardiomyopathy in desminopathy patients. Therefore, cardiac MRI may serve as a screening tool to identify patients at risk, which might benefit from early pharmacological and/or interventional (e.g. implantable cardioverter-defibrillator devices) therapy.  相似文献   
994.
BACKGROUND: Hippocampal volume reduction is a well replicated finding in schizophrenia. Evidence indicates a contribution of genetic and environmental factors, especially the influence of obstetric complications to this volume reduction. The aim of this study was to compare hippocampal volume of schizophrenic patients as well as and their relatives with control subjects and to quantify the additional contribution of obstetric complications. METHODS: T1 weighted MRI brain scans of 50 schizophrenic patients, 88 first-degree relatives and 53 healthy control subjects were used to perform volumetric measurements on the left and right hippocampus. A set of clinical measures including obstetric complications were recorded for all family members. RESULTS: Numerically our measurements revealed a hippocampal volume reduction in schizophrenic patients (left: - 14%, right: - 15%) and, although less pronounced, in their unaffected relatives (left: - 6%, right: - 10%). Noted differences in hippocampal volume between schizophrenic patients and controls were only significant for the left side. Hippocampal volumes of patients and their relatives with obstetric complications were reduced bilaterally. CONCLUSIONS: Hippocampal volume reduction is present in schizophrenic patients and their first-degree relatives, suggesting an influence of genetic factors.. In addition, however, obstetric complications have also been shown to play a major role.  相似文献   
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Abdominal Radiology - To assess the extents of pelvic floor descent both during the maximal straining phase and the defecation phase in healthy volunteers and in patients with pelvic floor...  相似文献   
998.
Whole‐body vibration (WBV) training is commonly practiced and may enhance peripheral blood flow. Here, we investigated muscle morphology and acute microcirculatory responses before and after a 6‐week resistive exercise training intervention without (RE) or with (RVE) simultaneous whole‐body vibrations (20 Hz, 6 mm peak‐to‐peak amplitude) in 26 healthy men in a randomized, controlled parallel‐design study. Total haemoglobin (tHb) and tissue oxygenation index (TOI) were measured in gastrocnemius muscle (GM) with near‐infrared spectroscopy (NIRS). Whole‐body oxygen consumption (VO2) was measured via spirometry, and skeletal muscle morphology was determined in soleus (SOL) muscle biopsies. Our data reveal that exercise‐induced muscle deoxygenation both before and after 6 weeks training was similar in RE and RVE (= 0·76), although VO2 was 20% higher in the RVE group (P<0·001). The RVE group showed a 14%‐point increase in reactive hyperaemia (= 0·007) and a 27% increase in blood volume (P<0·01) in GM after 6 weeks of training. The number of capillaries around fibres was increased by 15% after 6 weeks training in both groups (P<0·001) with no specific effect of superimposed WBV (= 0·61). Neither of the training regimens induced fibre hypertrophy in SOL. The present findings suggest an increased blood volume and vasodilator response in GM as an adaptation to long‐term RVE, which was not observed after RE alone. We conclude that RVE training enhances vasodilation of small arterioles and possibly capillaries. This effect might be advantageous for muscle thermoregulation and the delivery of oxygen and nutrients to exercising muscle and removal of carbon dioxide and metabolites.  相似文献   
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