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1.
2.
M. Puka-Sundvall E. Gilland E. Bona A. Lehmann M. Sandberg H. Hagberg 《Metabolic brain disease》1996,11(2):109-123
The aim of this study was to investigate the possible role of excitatory amino acids (EAAs) and cysteine in the development of brain damage after hypoxia-ischemia (HI) in neonates. In a rat model of neonatal HI, changes in extracellular (ec) amino acids in cerebral cortex were measured with microdialysis and correlated with the extent of brain damage at the site of probe placement. Extracellular concentrations of glutamate, aspartate and cysteine increased during HI and remained elevated during reperfusion. During HI the pattern of EAA changes was the same in the infarcted, undamaged and border zone regions. During reperfusion, however, the ec concentrations of glutamate, aspartate and cysteine were higher in infarcted and border zone areas compared to undamaged tissue. HI also produced a slight increase of tissue concentration of cysteine and decrease of tissue concentration of glutamate in parietal cortex of the HI hemisphere. The effect of cysteine on brain damage induced by HI and glutamate was also investigated. A subtoxic dose of cysteine potentiated glutamate toxicity in the arcuate nucleus and enhanced brain infarction after HI in neonatal rats. The results show that in neonatal HI the extracellular levels of EAAs during HI are not directly related to brain injury but the EAA levels during reflow predict the extent of infarction. Cysteine increases HI-induced brain injury and potentiates glutamate toxicity in neonatal rats. Speculatively, elevated level of cysteine during reperfusion may participate in the excitotoxic cascade leading to brain injury. 相似文献
3.
Various neocortical areas from four females aged 16–24 years with Rett syndrome (RS) were investigated and compared with
brains of therapy-resistant partial epilepsy (TRPE) patients (18–25 years), infantile autism (IA), and control brains (24
and 58 years). The cytoarchitecture of area 10 (frontal), area 21 (temporal), area 4 (primary motor cortex), and area 17 (primary
visual cortex) was studied by the combined Klüver-Barrera (luxol fast blue and cresyl violet) standard procedure. Autofluorescence
of lipofuscin, immunofluorescence of synaptic vesicle proteins [synaptophysin (p38)] and lectin-stained (Wisteria floribunda agglutinin) perineuronal nets (PNs) were studied in the cortices using dual-channel confocal laser scanning microscopy. The
brains of RS females show various types of morphological/cytoarchitectonical abnormalities of single pyramidal neurons in
layers II–III, and V–VII of different cortical areas. The abnormalities include mild losses of pyramidal neurons, more pronounced
in layers II and III than in layers V and VII, and more evident in frontal and temporal areas than in the visual cortex. Microdysgenesis,
including abnormalities due to neuronal migration disorders, was not found in RS, in contrast to the observations in TRPE
patients, strongly indicating that RS is not a neuronal migration disorder. Lipofuscin distribution was normal but amounts
were lower in RS cases than in control and TRPE brains. PNs were less expressed in cortices of the IA case, but were clearly
overexpressed in the motor cortex of RS. Quantitative analysis of p38 showed a decrease in the area occupied by p38 immunoreactivity
by 20–40% in RS compared with controls. It is concluded that RS could best be explained by a postnatal synaptogenic developmental
deficiency; the basic defect, however, is still completely unknown.
Received: 26 February 1996 / Revised, accepted: 11 July 1996 相似文献
4.
M Hagberg H Morgenstern M Kelsh 《Scandinavian journal of work, environment & health》1992,18(6):337-345
In this investigation reported epidemiologic studies on carpal tunnel syndrome (CTS) (15 cross-sectional studies involving 32 occupational or exposure groups and six case-referent studies) were reviewed. The prevalence of CTS in the different occupational groups varied between 0.6 and 61%. The highest prevalence was noted for grinders, butchers, grocery store workers, frozen food factory workers, platers, and workers with high-force, high-repetitive manual movements. Odds ratios greater than 10 were reported for exposed groups in three studies. On the basis of epidemiologic and other evidence, it was concluded that exposure to physical work load factors, such as repetitive and forceful gripping, is probably a major risk factor for CTS in several types of worker populations. At least 50%, and as much as 90%, of all of the CTS cases in these exposed populations appeared to be attributable to physical work load. 相似文献
5.
Salla disease variants. Sialoylaciduric encephalopathy with increased sialidase activity in two non-Finnish children 总被引:2,自引:0,他引:2
V Ylitalo B Hagberg J Rapola J E M?nsson L Svennerholm G Sanner B Tonnby 《Neuropediatrics》1986,17(1):44-47
The case reports of two Swedish girls with initially pseudostationary clinical pictures, one simulating ataxic and the other dyskinetic cerebral palsy, are presented. It was eventually revealed that they had a slowly progressive encephalopathy with pronounced gross motor disability and signs of severe dyskinesia, but only mild intellectual delay. Electron microscopy of skin biopsies showed a picture identical to that in Salla disease. They had a moderately increased 5-10 fold urinary free sialic acid excretion, increased sialidase activity in lymphocytes but normal activity in cultured fibroblasts. These two Swedish cases represent variants of Salla disease, a group of conditions with probable genetic heterogeneity. 相似文献
6.
Depression and a reduction in the performance of pleasant activities have been reported in patients with end-stage renal disease receiving hemodialysis therapy. The purpose of this study was to examine the relationship between depression and the patients' capacity to engage in physical activity. The patients' VO2max, or maximal oxygen consumption, was found to be positively associated with three standardized self-report measures of depression in a sample of 15 patients receiving hemodialysis. The clinical and theoretical implications of this finding are considered. 相似文献
7.
M. Hagberg S. Ahlstedt L. Hanson 《European journal of clinical microbiology & infectious diseases》1982,1(1):59-65
Antibodies againstEscherichia coli O antigen from rabbits immunized with formalin-killed bacteria were tested for cytotoxic capacity in an antibody-dependent cell-mediated cytotoxicity (ADCC) assay with human lymphocytes as effector cells and autologous papainized erythrocytes coated with O antigen as target cells. The cytotoxic titres were compared with the titres obtained with three methods of antibody quantitation. It was found that ADCC recorded antibodies with similar sensitivity as the enzyme-linked immunosorbent assay (ELISA) for IgG, but was much more sensitive than the ammonium sulphate precipitation (ASP) and indirect haemagglutination (IHA) usingβ-mercaptoethanol reduced sera. The ADCC titres were found to correlate very well with the titres obtained with ASP, ELISA and IHA for IgG but not for IgM, which is in accordance with a previous notion that ADCC is primarily mediated via IgG antibodies. ADCC should be considered as a possible immunopathologic mechanism in renal parenchymal damage in connection with urinary tract infections. 相似文献
8.
Rabon-Stith KM Hagberg JM Phares DA Kostek MC Delmonico MJ Roth SM Ferrell RE Conway JM Ryan AS Hurley BF 《Experimental physiology》2005,90(4):653-661
To determine the influence of the vitamin D receptor (VDR) gene FokI and BsmI genotype on bone mineral density response to two exercise training modalities, 206 healthy men and women (50-81 years old) were studied before and after approximately 5-6 months of either aerobic exercise training (AT) or strength training (ST). A totla of 123 subjects completed AT (51 men, 72 women) and 83 subjects completed ST (40 men, 43 women). DNA was extracted from blood samples of all subjects and genotyping was performed at the VDR FokI and BsmI locus to determine its association to training response. Total body, greater trochanter and femoral neck bone mineral density (BMD) were measured before and after both training programmes using dual-energy X-ray absorptiometry. VDR BsmI genotype was not significantly related to BMD at baseline or after ST or AT. However, VDR FokI genotype was significantly related to ST- but not AT-induced changes in femoral neck BMD (P < 0.05). The heterozygotes (Ff) in the ST group approached a significantly greater increase in femoral neck BMD (P = 0.058) compared to f homozygotes. There were no significant genotype relationships in the AT group. These data indicate that VDR FokI genotype may influence femoral neck BMD response to ST, but not AT. 相似文献
9.
Older and younger aerobically trained and sedentary adults participated in an S1-S2-S3 paradigm designed to elicit event-related potential (ERP) and behavioral responses to determine the influence of cardiovascular fitness on cognitive and motor processes. The paradigm provided warning (S1) as to the difficulty level of an upcoming decision task (S2). Participants had to decide the taller of two bars on presentation of S2 but hold their response until S3, to which they indicated their choice motorically. Results revealed age-related differences for ERP measures as older participants showed increased amplitude of the stimulus preceding negativity (SPN) prior to S2, and longer latencies and equipotentiality of P3 in response to S2. Fitness effects were also observed for the contingent negative variation (CNV) with decreased amplitude for fit relative to sedentary individuals. Age interacted with fitness for P3 latency to S2 as older sedentary individuals showed the longest latency followed by older fit and both younger groups. No significant group differences were observed for reaction time (RT) to S3. Therefore, physical fitness is associated with attenuation of cognitive decline in older individuals and greater economy of motor preparation for both young and older participants. 相似文献
10.
Helen Elden Hans-Christian Ostgaard Monika Fagevik-Olsen Lars Ladfors Henrik Hagberg 《BMC complementary and alternative medicine》2008,8(1):34