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21.
Recent studies of the association between the metabotropic glutamate receptor 3 gene (GRM3) and schizophrenia have produced conflicting results, although GRM3 is a promising candidate gene. Fujii et al. found a single nuclear polymorphism (SNP) for within this gene, rs1468412 to have a positive association to schizophrenia in Japanese patients. To investigate this further, we genotyped 7 SNPs around GRM3 including rs1468412, in 752 Chinese patients with schizophrenia and 752 controls using Taqman technology. We did not detect any association between rs1468412 and schizophrenia, however we found differences in the allele frequency distribution of SNP rs2299225 (p=0.0297, odds ration [OR]=1.44, 95% confidence interval 1.05-1.99) between cases and controls. Moreover, the overall frequency of haplotypes constructed from three SNPs including rs2299225 showed significant differences between cases and controls (p=0.0017). Our results partially support the previous studies in other ethnic groups and indicate that the GRM3 gene may play an important role in the etiology of schizophrenia in the Han Chinese.  相似文献   
22.
Objective The purpose of our study was twofold: to better understand the relationship between medial meniscal extrusion (MME) and degenerative joint disease (DJD), and to determine whether a relationship exists between MME and medial meniscal root (MMR) pathology, radial tear and joint effusion.Design and patients Two hundred and five consecutive MR imaging examinations of the knee were prospectively evaluated, regardless of indication, for the presence and degree of MME, medial compartment marginal osteophytes, medial compartment articular cartilage loss, joint effusion, medial meniscal tear and MMR pathology. MME 3 mm was considered abnormal. All studies were performed using a 1.5 T GE Signa MR unit with a quadrature knee coil. The standard protocol included oblique sagittal, coronal and axial imaging.Results We found a strong association (P<0.0001) between 3 mm MME and medial joint line osteophytosis (77%), medial compartment articular cartilage loss (69%), MMR pathology (64%) and radial tear (58%) when compared with knees without these findings. Fifty-one percent of cases with a moderate/large joint effusion had <3 mm MME. We found that 20% (31/155) of patients with minimal or no evidence of DJD had 3 mm MME. Of this group, 62% (19/31) had either MMR pathology and/or radial tear, 13% (4/31) had joint effusion as their only abnormality and 6% (2/31) had a normal examination (other than the presence of MME). The remaining 19% consisted of three cases of different types of meniscal tear and three cases of small joint effusions but no other detectable pathology.Conclusion MME 3 mm is strongly associated with DJD, MMR pathology and radial tear. A significant number of cases with no or minimal evidence of DJD (20%) had 3 mm MME, suggesting that MME precedes, rather than follows, the development of DJD. We also found that joint effusion was not strongly associated with 3 mm MME.This paper was presented at the 2003 ARRS meeting  相似文献   
23.
A case control investigation was performed to examine the relatively high rate of unrecognized psychotic illness within an extended family with a high-density of psychotic illness and identify factors related to nonrecognition. The study was conducted within the catchment area of a Regional Mental Health Center in central Israel. Subjects were recruited using clinic records indicating multiple family members with mental illness. Additional subjects were recruited in the homes of the subjects through family members. A total of 247 subjects were recruited, 111 of whom were determined to suffer from a psychotic disorder based on criteria in standard use. Sixty-six subjects were members of a single extended family (clan) and 181 subjects were members of nonrelated families residing in the same geographic area. While the rate of unrecognized psychotic illness was insignificant among the members of the families not related to the clan, among clan members the rate of unrecognized psychotic illness was 45%. Among this clan, recognition of psychotic illness appeared to be directly related to disruptive behavior. Additionally, it was found that, overall, subjects were more likely to recognized by the mental health system if they had fewer ill family members and more education. We conclude that although nonrecognition of mental illness does not appear to be a problem among the families in the area who are not related to the particular clan, within the clan a particular subculture appears to have developed in which perceived need for psychiatric services is related to disruptive behavior. A high density of psychotic illness within a family and less education may create a family environment that becomes tolerant of psychotic symptoms that are not disruptive to others, resulting in nonrecognition of nondisruptive illness by the mental health system.  相似文献   
24.
A major focus of attention in structural brain-imaging research in major depression is the increased prevalence of T2-weighted image 'hyperintensities' (T2-WIH). Our aims in this study were to characterize the distribution and magnetic resonance imaging (MRI) presentation of brain hyperintensities in major depression patients compared to healthy control subjects and to explore the association between the presence of T2-WIH and measures of clinical and cognitive state. Thirty-seven patients suffering from major depression and 27 age- and sex-matched healthy controls underwent brain MRI and were evaluated by the Hamilton Rating Scale for Depression, the Mini Mental State Examination and the Haschinsky Ischaemia Index. T2-WIH (at least one) were found in 26 out of 37 major depression patients and 7 out of 27 controls (p=0.0001). The number of brain T2-WIH was significantly and positively correlated with age in depressed (p=0.001) but not in healthy subjects. Mean volume of T2-WIH was significantly greater (p=0.004) in depressed subjects. In the control group T2-WIH were exclusively located in the supratentorial hemispheral white matter while in the depressed group T2-WIH were also found in basal ganglia, temporal lobe, cerebellum and brainstem. More (52 vs. 20%; p=0.018) T2-WIH were demonstrable on T1 in depressed subjects. Depressed patients with T2-WIH in basal ganglia were clearly the most severely depressed and cognitively impaired subjects, and may constitute a clinically distinct subgroup within major depression.  相似文献   
25.
BACKGROUND: Tumor necrosis factor alpha (TNFalpha), a cytokine involved in inflammatory processes, has been implicated in the pathophysiology of schizophrenia. The chromosomal location in the major histocompatibility complex (MHC) region on 6p21.1-21.3, a region with evidence for linkage, suggests a role in susceptibility to schizophrenia. Association of the minor (A) allele of the -G308A TNFalpha gene polymorphism with schizophrenia has been reported [Mol. Psychiatry 6 (2001) 79]. METHODS: Association of the -G308A TNFalpha gene and the lymphotoxin alpha (LTalpha)+A252G gene polymorphisms with schizophrenia was studied in 79 sib pair families with linkage in the MHC region and in 128 trio families using the transmission disequilibrium test (TDT). RESULTS: Weak association of the common G allele was detected for TNFalpha -G308A in both samples independently with borderline significance in the sib pair families (0.064) and with a nominally significant value of P=0.022 in the trio families. Combining both samples produced P=0.003, while LTalpha+A252G, located approximately 2-3 kb distally, revealed P=0.03 and the two locus haplotype yielded a P value of 0.001. CONCLUSION: Our data suggests association of the common G allele of the -G308A TNFalpha gene polymorphism with schizophrenia in a sample of 207 families. However, linkage disequilibrium with a different allele of the TNFalpha gene or another gene in the MHC region cannot be excluded.  相似文献   
26.
Substantial evidence supports a role for dysfunction of brain serotonergic (5-HT) systems in the pathogenesis of major affective disorder, both unipolar (recurrent major depression) and bipolar.(1) Modification of serotonergic neurotransmission is pivotally implicated in the mechanism of action of antidepressant drugs(2) and also in the action of mood stabilizing agents, particularly lithium carbonate.(3) Accordingly, genes that code for the multiple subtypes of serotonin receptors that have been cloned and are expressed in brain,(4) are strong candidates for a role in the genetic etiology of affective illness. We examined a structural variant of the serotonin 2C (5-HT2C) receptor gene (HTR2C) that gives rise to a cysteine to serine substitution in the N terminal extracellular domain of the receptor protein (cys23ser),(5) in 513 patients with recurrent major depression (MDD-R), 649 patients with bipolar (BP) affective disorder and 901 normal controls. The subjects were drawn from nine European countries participating in the European Collaborative Project on Affective Disorders. There was significant variation in the frequency of the HT2CR ser23 allele among the 10 population groups included in the sample (from 24.6% in Greek control subjects to 9.2% in Scots, chi(2) = 20.9, df 9, P = 0.01). Logistic regression analysis demonstrated that over and above this inter-population variability, there was a significant excess of HT2CR ser23 allele carriers in patients compared to normal controls that was demonstrable for both the MDD (chi(2) = 7.34, df 1, P = 0.006) and BP (chi(2) = 5.45, df 1, P = 0.02) patients. These findings support a possible role for genetically based structural variation in 5-HT2C receptors in the pathogenesis of major affective disorder.  相似文献   
27.
Tardive dyskinesia (TD) is a long-term adverse effect of antipsychotic drugs that are dopamine D2 receptor blockers.(1) Serotonin receptor antagonism has been proposed as a common mechanism contributing to the low extrapyramidal effects profile of atypical antipsychotic drugs.(2) We examined the association of three polymorphisms in the 5-HT2A receptor gene (HTR2A) with TD susceptibility--T102C(3) and his452tyr(4) in the coding region and A-1438G(5) in the promoter--in matched schizophrenia patients with (n = 59, SCZ-TD-Y) and without TD (n = 62, SCZ-TD-N) and normal control subjects (n = 96). The T102C and the A-1438G polymorphisms are in complete linkage disequilibrium but not his452tyr. There was a significant excess of 102C and -1438G alleles (62.7%) in the SCZ-TD-Y patients compared to SCZ-TD-N patients (41.1%) and controls (45.9%; chi(2) = 12.8, df = 2, P = 0.002; SCZ-TD-Y vs SCZ-TD-N, chi(2) = 11.4, df = 1, P = 0.0008, OR 2.41, 95% CI 1.43-3.99) and of 102CC and -1438GG genotypes (SCZ-TD-Y 42.4%, SCZ-TD-N, 16.1%, controls 20.8%, chi(2) = 13.3, df = 4, P = 0.01). The 102CC and the -1438GG genotypes were associated with significantly higher AIMS trunk dyskinesia scores (F = 3.9; df = 2, 116; P = 0.02) and more incapacitation (F = 5.0; df = 2, 115; P = 0.006). The his452tyr polymorphism showed no association with TD. These findings suggest that the 5-HT2A receptor gene is significantly associated with susceptibility to TD in patients with chronic schizophrenia. Previously reported association of the T102C and A-1438G polymorphisms with schizophrenia(6) may reflect association of a sub-group of patients with a susceptibility to abnormal involuntary movements related to antipsychotic drug exposure.  相似文献   
28.
Clomipramine is a tricyclic antidepressant drug with a high affinity for the serotonin (5-HT) uptake site or transporter. Electrophysiological experiments have provided evidence that repeated administration of clomipramine induces an increase in the sensitivity of postsynaptic 5-HT(1A) receptors in the hippocampus. We have studied the effects of clomipramine, administered to rats at a dose of 10mg/kg/day for 28 days by osmotic minipumps, on presynaptic 5-HT(1A) and 5-HT(1B) autoreceptors in the hypothalamus, and on postsynaptic 5-HT(1A) receptors in the hippocampus, by using in vivo microdialysis to measure 5-HT and cyclic adenosine monophosphate (cAMP) levels. Postsynaptic 5-HT(1A) receptor sensitivity in the hypothalamus was determined by means of a neuroendocrine challenge procedure. Although the sensitivity of presynaptic 5-HT(1A) autoreceptors, as measured by the effect of a subcutaneous (s.c.) injection of 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT, 0.2mg/kg or 50 microg/kg) to reduce 5-HT levels, did not change, there was a reduction in sensitivity of presynaptic 5-HT(1B) receptors, as measured by the effect of an injection of the 5-HT(1B/1D) antagonist GR 127935 (5mg/kg, s.c.) to increase 5-HT levels. This effect probably accounted for the increase in basal 5-HT levels observed in the hypothalamus after chronic clomipramine administration. Postsynaptic 5-HT(1A) receptor sensitivity in the hippocampus, measured by the effect of 8-OH-DPAT to increase cAMP levels in the dialysate, was increased after chronic clomipramine. Animals that had received daily intraperitoneal injections of 10mg/kg clomipramine for 28 days did not show a change in postsynaptic 5-HT(1A) receptor sensitivity in the hypothalamus as measured by the ability of 8-OH-DPAT (50 microg/kg, s.c.) to stimulate secretion of corticosterone. Taken together with the results of previous experiments involving the cerebral cortex, these in vivo results show that chronic clomipramine exerts effects on both pre- and postsynaptic serotonin receptors, but that these effects are highly region-specific.  相似文献   
29.
OBJECTIVES: Carriers of the mutations 185delAG and 5382insC in the BRCA1 gene and 6174delT in the BRCA2 gene have a substantial life-time risk for breast and ovarian cancers (BC and OC). The aim of the study was to identify the clinical features and the hormonal risk modifiers in mutation carriers and the implication in suggested guidelines for treatment decisions in BRCA1/2 carrier patients. STUDY DESIGN: Breast and/or ovarian cancer patients from the Oncology and Cancer Genetic clinics were tested for the three Ashkenazi founder mutations: 87 patients were identified as carriers of one of these mutations. Clinical presentation and age at onset were correlated with the mutations, in patients with bilateral BC or BC and OC, the length of time that elapsed between the diagnosis of the two cancers was recorded. We compared BC and OC patients with regard to ages at menarche, first pregnancy and menopause, number of pregnancies and deliveries, the use of oral contraceptives, hormonal replacement therapy and fertility treatments. RESULTS: The carriers of the three BRCA1/2 Ashkenazi founder mutations did not differ in clinical presentation nor age at onset. Forty-three patients (74.1%) of 58 BC patients were diagnosed between the ages 30 and 50, only four (6.9%) patients were diagnosed after age 60. Of BC patients diagnosed before age 35, 63.6% developed second BC as compared to 25.5% of those diagnosed after age 35. Ovarian cancer was diagnosed after age 45 in 89.7% of the patients, only one patient was diagnosed under the age of 40. Oral contraceptives use was documented in 61.3% of BC patients as compared to 11.8% of OC patients. Other hormonal factors did not differ between the two groups. CONCLUSIONS: The carriers of the three Ashkenazi founder mutations should be considered at the same risk for BC and for OC and treatment options should be the same. Mutation carriers diagnosed with BC before the age of 35 are at a very high risk for developing second breast cancer. Most ovarian cancers in carriers were diagnosed after age 45, and prophylactic oophorectomy should be postponed to the age of 45. Oral contraceptives might elevate the risk of BC in mutation carriers.  相似文献   
30.
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