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61.
There were 157 patients with rheumatoid arthritis. Of these, only 65 patients (41.4%) failed to show any factor at the disease onset, which could be estimated as provoking. Psychoemotional factor was most common (in 47.7% of cases). Later the indicated factor played a more important part: only 5.1% of the patients denied or doubted it. In most cases, the distress was caused by family relations. There was an appreciable difference in the intensity of the problems in family and single patients. Affective disorders (neurotic and hypopsychotic depressions) were mostly recorded among mental disorders. The life quality determined in accordance with the self-estimation of the "health" and happiness" noticeably depended both on biological factors (pain intensity, the degree of damage to the bones and joints, and the disease stage) and on social factors--the educational level and social position. The degree of personality merits defined according to the self-estimation of the "mentality" and "character" appeared higher in persons with higher education and in patients suffering from erosive arthritis. The data obtained provide evidence for the necessity of psychosomatic orientation of practicing physicians.  相似文献   
62.
We revised our hypothesis that the absence of motor behavior impairments at the presymptomatic stage of Parkinsonism, when degeneration of nigrostriatal dopaminergic neurons has already occurred, is the result of compensatory maintenance of a normal extracellular dopamine (DA) concentration in the striatum. We used microdialysis to measure extracellular levels of DA, its precursor L-dihydroxyphenylalanine (L-DOPA), and its metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in mouse striatum in a model of the presymptomatic stage of Parkinsonism. This stage was induced by a single subcutaneous injection of the neurotoxin precursor 1-methyl-4-phenyl-1,2,3,4-tetrahydropyridine (MPTP) at a dose of 12 mg/kg. At 14 days after MPTP injection, the extracellular DA content substantially decreased as compared to the control; however, it did not result in alterations of motor behavior, probably due to compensatory processes directed, not to the maintenance of extracellular DA at the normal level, but rather to the elevation of neuronal sensitivity to DA. The extracellular L-DOPA content remained at the normal level. We did not find any changes in the DOPAC and HVA contents.  相似文献   
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Rhabdoid phenotype and loss of SMARCB1 expression in a brain tumor are characteristic features of atypical teratoid/rhabdoid tumors (ATRT). Rare non‐rhabdoid brain tumors showing cribriform growth pattern and SMARCB1 loss have been designated cribriform neuroepithelial tumor (CRINET). Small case series suggest that CRINETs may have a relatively favorable prognosis. However, the long‐term outcome is unclear and it remains uncertain whether CRINET represents a distinct entity or a variant of ATRT. Therefore, 10 CRINETs were clinically and molecularly characterized and compared with 10 ATRTs of each of three recently described molecular subgroups (i.e. ATRT‐TYR, ATRT‐SHH and ATRT‐MYC) using Illumina Infinium HumanMethylation450 arrays, FISH, MLPA, and sequencing. Furthermore, outcome was compared to a larger cohort of 27 children with ATRT‐TYR. Median age of the 6 boys and 4 girls harboring a CRINET was 20 months. On histopathological examination, all CRINETs demonstrated a cribriform growth pattern and distinct tyrosinase staining. On unsupervised cluster analysis of methylation data, all CRINETs examined exclusively clustered within the ATRT‐TYR molecular subgroup. As ATRT‐TYR, CRINETs mainly showed large heterozygous 22q deletions (9/10) and SMARCB1 mutations of the other allele. In two patients, SMARCB1 mutations were also present in the germline. Estimated mean overall survival in patients with CRINETs was 125 months (95% confidence interval 100–151 months) as compared to only 53 (33–74) months in patients with ATRTs of the ATRT‐TYR subgroup (Log‐Rank P < 0.05). In conclusion, CRINET represents a SMARCB1‐deficient non‐rhabdoid tumor, which shares molecular similarities with the ATRT‐TYR subgroup but has distinct histopathological features and favorable long‐term outcome.  相似文献   
65.
A recent study reported on mutations in the active site of the isocitrate dehydrogenase (IDH1) gene in 12% of glioblastomas. All mutations detected resulted in an amino acid exchange in position 132. We analyzed the genomic region spanning wild type R132 of IDH1 by direct sequencing in 685 brain tumors including 41 pilocytic astrocytomas, 12 subependymal giant cell astrocytomas, 7 pleomorphic xanthoastrocytomas, 93 diffuse astrocytomas, 120 adult glioblastomas, 14 pediatric glioblastomas, 105 oligodendrogliomas, 83 oligoastrocytomas, 31 ependymomas, 58 medulloblastomas, 9 supratentorial primitive neuroectodermal tumors, 17 schwannomas, 72 meningiomas and 23 pituitary adenomas. A total of 221 somatic IDH1 mutations were detected and the highest frequencies occurred in diffuse astrocytomas (68%), oligodendrogliomas (69%), oligoastrocytomas (78%) and secondary glioblastomas (88%). Primary glioblastomas and other entities were characterized by a low frequency or absence of mutations in amino acid position 132 of IDH1. The very high frequency of IDH1 mutations in WHO grade II astrocytic and oligodendroglial gliomas suggests a role in early tumor development.  相似文献   
66.
Medulloblastoma is a highly malignant embryonal tumor of the cerebellum that accounts for 20%-25% of all intracranial pediatric tumors. The most frequent chromosomal rearrangement in medulloblastoma is isochromosome 17, or i(17q). Its frequency suggests that it serves an important role in tumor pathogenesis, possibly mediated by the disruption or permanent activation of a gene at the breakpoint. To address this question, we performed a detailed analysis of chromosome 17 DNA copy number from 18 medulloblastomas previously shown to carry an apparent i(17q). We identified two breakpoint regions, one well within band 17p11.2 (n = 16) and a second within the pericentromeric region (n = 2). To map the breakpoints more precisely, we constructed a tiling-path matrix-CGH array covering chromosomal band 17p11.2 to the centromere and utilized it to delineate two small breakpoint intervals mapping at Mb 19.0 and 21.7 in seven of the medulloblastomas and in nine hematological neoplasias with i(17q). The former interval contains two breakpoint clusters that each colocalize with a pair of head-to-head inverted DNA sequence repeats, and the latter maps close to a region of alpha-satellite repeats. No consensus coding sequence localizes in these regions. Together, these data strongly suggest that the effects of i(17q) in medulloblastoma are mediated by gene-dosage effects of genes on 17p or 17q rather than by the disruption or deregulation of a "breakpoint" gene. Furthermore, we identified artifacts introduced in DNA copy number data by cross-hybridization of low-copy repeat sequences and discuss the challenge these can pose in the interpretation of diagnostic microarrays.  相似文献   
67.
The cytogenetic profile of chromosome 17 was studied in 180 medlloblastomas by the interphasic FISH technique, which revealed the high incidence of this aberration and its association with the poor clinical course of the disease. The interphasic cytogenetic analysis of chromosome 17 abnormalities in medulloblastoma biopsy specimens may be recommended for its inclusion into a complex of laboratory diagnostic methods used in the examination of these tumors.  相似文献   
68.
Recently, we showed that genetic factors determine flow-dependent vascular remodeling. Among five inbred mouse strains, the SJL strain developed the largest intima in response to low flow. Because SJL mice have a spontaneous mutation in superoxide dismutase 2 (SOD-2) we tested the hypothesis that strain-specific variations in vascular function are due to alterations in redox and nitric oxide (NO) pathways. Vasorelaxation to acetylcholine was significantly impaired in aortic rings from SJL compared to C3H or FVB mice (up to 40%). Relaxation to the endothelium-independent vasodilator sodium nitroprusside (SNP) in SJL mice was also significantly impaired at low concentrations, with decreases in sensitivity and maximal relaxation to SNP compared to C3H and FVB mice. Western blot analyses showed significantly decreased expression (approximately 40%) of eNOS, PKG and SOD-2 proteins in SJL vasculature compared to C3H. Intact aortas from SJL showed significantly increased nitrotyrosine and decreased SOD-2 expression compared to C3H by immunohistochemistry. Basal levels of superoxide in aortas from SJL were not significantly different than C3H as measured by dihydroethidine. In summary, relatively small alterations in redox (SOD-2) and NO pathways (eNOS and PKG) may contribute to significantly impaired vasorelaxation in SJL mice.  相似文献   
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