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排序方式: 共有406条查询结果,搜索用时 15 毫秒
1.
Mònica Gratacòs Juan R González Josep M Mercader Rafael de Cid Mikel Urretavizcaya Xavier Estivill 《Neuropsychopharmacology》2007,61(7):911-922
BACKGROUND: There is an increasing recognition that the pathophysiology of mental disorders could be the result of deregulation of synaptic plasticity with alterations of neurotrophins. The valine (Val)66-to-methionine (Met) variant, located in the pro brain-derived neurotrophic factor (BDNF) sequence, has been extensively studied through linkage and association approaches in several psychiatric disorders. METHODS: We performed a meta-analysis restricted to individual case-control studies in different categories of mental disorders and BDNF Val66Met polymorphism. We included data from 39 case-control studies encompassing psychiatric phenotypes: eating disorders, substance-related disorders, mood disorders, and schizophrenia, among others. RESULTS: The association of Val66Met was confined to three diagnoses: substance-related disorders, eating disorders, and schizophrenia. The Val/Met and the Met/Met genotypes increase the risk for eating disorders up to 33%, while these same genotypes confer a 21% protective effect in substance-related disorders. The homozygous carriers Met/Met showed a 19% increased risk of schizophrenia with respect to the heterozygous state. CONCLUSIONS: The study confirms the association of Val66Met to substance-related disorders, eating disorders, and schizophrenia. It remains to be determined if other variants in tight linkage disequilibrium with Val66Met could configure an extended functional haplotype that would explain observed discrepancies in risk estimations across studies. 相似文献
2.
Secretion of Igs and surface expression of HLA antigens was examined in lymphoid cells as a function of temp. Upon reducing the temp from 37 to 20 degrees C a progressive decrease in the secretion of Ig and surface expression of HLA antigens was noted. When the status of the oligosaccharides present on these glycoproteins was examined, conversion of high-mannose [endo-beta-N-acetylglucosaminidase-(Endo H) sensitive] to complex-type (Endo H resistant) oligosaccharides diminished with decreasing temp. At no time was an accumulation of Endo H resistant glycoproteins seen intracellularly. These results show that the phenomenon observed for synthesis and intracellular transport of viral glycoproteins in epithelial cells at reduced temp, namely intracellular accumulation of viral glycoproteins carrying complex sugar moieties, does not necessarily apply to glycoprotein transport in lymphoid cells. A difference in subcellular organization of epithelial and lymphoid cells may be responsible for this discrepancy. 相似文献
3.
M. G. De Simoni V. Guardabasso K. Misterek S. ALgeri 《Naunyn-Schmiedeberg's archives of pharmacology》1982,321(2):105-111
Summary Rats were made tolerant to morphine or to DALA, a synthetic analogue of met-enkephalin, by prolonged exposure to these compounds. Tolerance was assessed by evaluating the resistance of the treated rats to present catalepsy after an acute dose of the opiates. Both morphine and DALA induced tolerance and cross-tolerance to the cataleptic effect. Acute administration of morphine and DALA increased the concentration of DOPAC in striatum, limbic area and s.nigra of control rats. This increase was not present when morphine was given acutely to chronically morphine-treated rats, indicating that these animals were tolerant to this effect. Chronically morphine-treated rats given DALA presented partial tolerance to the biochemical effect of the peptide in limbic area and in s.nigra but not in striatum, indicating that only in certain areas was crosstolerance produced by chronic morphine. When DALA was administered at different doses to chronically DALA treated rats, the peptide induced rise in DA catabolite was similar to that produced in control animals, so clearly there was no tolerance to this biochemical effect. In these animals cross tolerance to morphine's effect on DA metabolism was present in s.nigra but not in the other two areas, indicating that s.nigra is particularly sensitive to opiate-induced tolerance on DA metabolism.Supported by CNR-ROME Grant no. CT81.00258.04 相似文献
4.
《Xenobiotica; the fate of foreign compounds in biological systems》2013,43(10):952-956
Abstract1.?Fibromyalgia syndrome (FMS) is a common chronic widespread pain syndrome mainly affecting women. The aim of this study was to explore the frequency and clinical significance of catechol-O-methyltransferase (COMT) gene Val158Met polymorphism in a large cohort of Turkish patients with FMS.2.?The study included 379 FMS patients and 290 controls. Genomic DNA was isolated and genotyped using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analyses.3.?The genotype frequencies of Val158Met polymorphism showed a small difference between FMS patients and healthy controls (p?=?0.047), however, the Met/Met genotype was significantly higher in FMS patients than healthy controls (p?=?0.016). No difference was observed for allele frequencies between two groups. Stratification analysis according to clinical features for this disease reveals that weight, FMS Impact Questionnaire score, algometry and Raynaud’s syndrome, were detected to have statistically significant associations with Val158Met polymorphism (p?=?0.037, p?=?0.042, p?=?0.039 and p?=?0.033, respectively). Pain sensitivity, measured by algometry, was statistically higher in patients with Met/Met genotype than the patients with Val/Val and Val/Met genotypes (p?=?0.017).4.?The results of this study suggested that COMT gene Val158Met polymorphism is positively associated with FMS and play a relevant role in the clinical symptoms of the disease. 相似文献
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6.
G. Dharaniprasad A. Samantaray L. Srikanth M. HanumanthaRao A. Chandra P.V.G.K. Sarma V. Bhan 《Revista espa?ola de anestesiología y reanimación》2021,68(3):128-136
ObjectivesMutations in the exon 4 of the COMT gene are associated with chronic persistent surgical pain (CPSP). Especially COMT mutated allele G472A (Val158Met) associated with CPSP patients is reported in different ethnic population. The purpose of this study is to evaluate the prevalence of genetic mutations and structural variations in exon 4 of COMT that can be related to the appearance of CPSP in patients under sternotomy.Materials and methodsOne hundred patients with American Society of Anesthesiologists (ASA) physical status grades i, ii and iii, who underwent sternotomy procedures, were selected to assess the development and magnitude of the CPSP evaluated with pain questionaries’ at the end of three months after surgery. This was correlated with COMT allele presence. The exon 4 of COMT gene (that contains the G472A allele) was studied. The polymerase chain reaction (PCR) products were sequenced and mutated sequences were deposited in GenBank®. The structural analysis of COMT was performed using ProCheck® and distortions of three-dimensional tertiary structural orientation was evaluated with root-mean-square deviation (RMSD) score.ResultsGenetic analysis carried out through PCR showed 220 bp amplicons. The 25% of patients with CPSP showed a Numeric Rating Scale (NRS) > 4 pain score. The 20% of these patients have known Val158Met mutation, 5% of patients showed novel mutations c.382C>G, c.383G>C, p.(Arg128Ala). The mutations in COMT gene contributed major structural variations in COMT leading to the formation of inactive COMT that correlates with CPSP.ConclusionThe results of the present study showed that both novel and previously reported mutations in COMT gene has strong association with CPSP. 相似文献
7.
IntroductionMissense variants and multiplications of the alpha-synuclein gene (SNCA) are established as rare causes of autosomal dominant forms of Parkinson's Disease (PD).MethodsTwo families of Turkish origins with PD were studied; the SNCA coding region was analyzed by Sanger sequencing, and by whole exome sequencing (WES) in the index patient of the first and the second family, respectively. Co-segregation studies and haplotype analysis across the SNCA locus were carried out. Functional studies included in vitro thioflavin-T aggregation assay and in silico structural modelling of the alpha-synuclein (α-syn) protein.ResultsWe identified a novel heterozygous SNCA variant, c.215C > T (p.Thr72Met), segregating with PD in a total of four members in the two families. A shared haplotype across the SNCA locus was found among variant carriers, suggestive of a common ancestor. We next showed that the Thr72Met α-syn displays enhanced aggregation in-vitro, compared to the wild-type species. In silico analysis of a tetrameric α-syn structural model revealed that Threonine 72 lies in the tetrameric interface, and substitution with the much larger methionine residue could potentially destabilize the tetramer.ConclusionWe present clinical, genetic, and functional data supporting a causative role of the SNCA c.215C > T (p.Thr72Met) variant in familial PD. Testing for this variant in patients with PD, especially of Turkish origin, might detect additional carriers. Further functional analyses might offer new insights into the shared biochemical properties of the PD-causing SNCA missense variants, and how they lead to neurodegeneration. 相似文献
8.
9.
Mesenchymal/radioresistant traits in granular astrocytomas: evidence from a combined clinical and molecular approach 下载免费PDF全文
10.
Despite a significant increase in the size of the Asian American elderly population, little is known about their social service needs and the level of service being provided them. This study used a survey methodology to examine all Asian American senior programs (N = 20) in a major American metropolitan region. The response rate was 90% with respondent agencies serving as the unit of analysis. Findings suggest that Asian elderly clients were primarily women and 'old-old', and that many of them were on SSI. Services provided were primarily tangible and facilitative, rather than clinical. Services needed but not provided were emergency psychiatric care, home attendants, home-delivered meals, legal services, medical services, and protective services. Findings of this study provide useful information for further research and program planning for Asian American elders in urban settings. 相似文献