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1.
BACKGROUND AND OBJECTIVE: Contradictory and confusing reports on serum dehydroepiandrosterone (DHEA) levels in schizophrenia led us to compare the serum concentration of its precursor, pregnenolone (PREG), between medicated schizophrenia patients and healthy subjects. The neurosteroid levels were monitored for two months and the relationship of these neurosteroids with schizophrenic symptomatology, emotional distress, and anxiety was examined. METHOD: We determined blood levels of PREG, and DHEA in 15 schizophrenia patients and 12 healthy controls at four time points: at the start of the study, after 2, 4 and 8 weeks. Analysis of covariance and canonical correlations across four time points were applied. RESULTS: Controlling for age, serum concentrations of PREG were lower, while the DHEA level and the molar ratio values of DHEA/PREG were higher in schizophrenia patients compared to healthy controls. Both levels of PREG and DHEA and their molar ratio did not change significantly during the study's period either among schizophrenia patients or healthy controls. The blood levels of PREG appear to be associated with trait-anxiety scores in the schizophrenia patients, while associations of clinical symptoms with two neurosteroids did not reach a significant level when the confounding effect of emotional distress, and anxiety scores was controlled. CONCLUSION: Low serum pregnenolone concentrations in schizophrenia appear to be associated with trait-anxiety scores independent of symptoms. Further research into the role of pregnenolone in schizophrenia is warranted.  相似文献   
2.
Neuroimaging in Pineal Tumors   总被引:4,自引:0,他引:4  
F Reis  MD  AV Faria  MD  PhD  VA Zanardi  MD  PhD  JR Menezes  MD  F Cendes  MD  PhD  LS Queiroz  MD  PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.  相似文献   
3.
The effects of rapid intravascular volume expansion were studied in 12 patients, 4 to 14 years after single prosthetic heart valve replacement. The data observed showed a statistically significant mean difference before and after volume expansion of right atrial mean pressure and right ventricular end diastolic and pulmonary capillary pressures. However, right atrial and pulmonary capillary pressures equilibration was not detected. The right atrial pressure form showed abnormal variations during inspiration. Dip and plateau right ventricular diastolic pressure configuration was recorded in 6 patients after expansion, was absent in 2 and questionable in 4. A deep Y descent with an M-shaped right atrial pressure form was recorded in all 12 patients. The explanation for these phenomena is unclear. Thus, in the absence of pressure equilibration and clinical evidence of constriction, the abnormalities recorded during rapid volume expansion should be cautiously interpreted.  相似文献   
4.
A case of true conversive hallucinations in a 19-year-old female soldier is described. This phenomenon is rare and should be distinguished from psychotic or dissociative states.  相似文献   
5.
6.
We determined the presence of antinuclear autoantibodies (ANA), antinative DNA and histone-reactive ANA in 3 groups of chronic schizophrenic patients (n= 85): haloperidol-treated patients (for at least 3 months) (n= 35), drug-free for at least 3 months (n= 35) and neuroleptic-naive patients (n= 15). The autoantibody titers were compared with those of healthy controls (n= 37). A significantly higher frequency of positive ANA was found among chronic schizophrenic patients (~20%) as compared with the controls (~5 %), irrespective of drug treatment, sex and age. No antinative ANA autoantibodies or histone reactive ANA were detected in either schizophrenic patients or controls. Further studies are needed to isolate and characterize in ANA-positive schizophrenic patients 1 a putative specific ANA profile.  相似文献   
7.
The brain vesicular monoamine transporter (VMAT2) is part of the re-uptake mechanism which regulates monoaminergic neurotransmission. We demonstrated previously a high degree of similarity between the pharmacodynamic characteristics of platelet and brain VMAT2. Nicotine induced increase of dopamine and serotonin neurotransmission in limbic structures may alter the expression of VMAT2 in brains of smokers. In this study we measured the VMAT2 pharmacodynamic characteristics using high-affinity [3H]dihydrotetrabenazine (TBZOH) binding to platelets of smokers (n=15) compared to sex and age matched healthy nonsmokers controls (n=14). A significant decrease (17%, P=0.02) in VMAT2 density (Bmax) was observed in platelets of smokers compared to nonsmokers. There was no significant difference in the affinity of [3H]TBZOH to its platelet binding site and the VMAT2 density did not correlate with the heaviness of smoking. The decreased density of the VMAT2 in the platelets of smokers may reflect nicotine induced desensitization of VMAT2, a phenomenon that may be relevant to the addictive properties of nicotine.  相似文献   
8.
The human small-conductance Ca(2+)-activated potassium channel gene KCNN3 has been involved in mechanisms underlying neuronal function and plasticity. A multiallelic CAG repeat polymorphism within the KCNN3 has been associated with schizophrenia and bipolar disorder. We have previously reported in a family-based study that longer CAG repeats are preferentially transmitted to patients with anorexia nervosa (AN). The present study extends the analysis of KCNN3 allele distribution to a larger series of AN female patients and control groups, incorporating information on ethnicity and co-morbidities associated with AN. The data analysis is presented while considering separately the two alleles of each individual, namely a minor (shorter) and a major (longer) allele. This study has found that the KCNN3 allele distribution in the general Israeli population does not differ significantly in at least four Jewish ethnic groups of Ashkenazi, North African, Iraqi, and Yemenite origin. These have been used as control groups in a matched case-control analysis that has demonstrated a significant over-representation of KCNN3 alleles with longer CAG repeats among AN patients (P < 0.001 for the major allele and P = 0.035 for allele sum). Under dichotomization, a significantly higher prevalence of the L allele (>19 repeats) has been observed among AN patients (P < 0.001). While considering AN and co-morbid phenotypes, a tendency towards longer (L) alleles has been observed in the subset of patients with obsessive-compulsive disorder (OCD) co-morbidity. These findings further implicate KCNN3 as a significant contributor to predisposition to AN.  相似文献   
9.
BACKGROUND: The knowledge available on electroconvulsive therapy (ECT) in adolescents is largely anecdotal, or based on findings from adults. The aim of the present study is to compare the use of ECT in adolescent and adult inpatients. METHODS: We retrospectively analyzed the files of all 36 adolescent (between the ages of 13 and 19) and 57 randomly selected adult inpatients (above the age of 20) treated with ECT in a university-affiliated mental heath center in Israel between 1991 and 1997. RESULTS: Sixty one percent of the adolescents improved by the end of treatment, and 53% were not hospitalized in the subsequent year. The respective percentages among adults were 83% and 49%. Whereas most adults were treated with ECT because of schizophrenic disorders, almost half of the adolescents received ECT for affective disorders. Significantly more adolescents were treated with ECT because of acute life-endangering conditions (catatonia or severe suicidal risk). No significant adverse effects were found in both groups. LIMITATIONS: Our study is based on a retrospective chart review. The adolescent and adult groups are different in psychiatric morbidity, diagnosis and outcome, have not been assessed in a blind manner, and we have not used standardized psychometric batteries for the evaluation of ECT-related memory disturbances. CONCLUSIONS: ECT may be an effective, well-tolerated and safe procedure in both adult and adolescent inpatients.  相似文献   
10.
Myo-inositol transport in the central nervous system   总被引:18,自引:0,他引:18  
  相似文献   
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