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41.
OBJECTIVE: To examine whether data on the clinical profiles of psychiatric service users can inform the claim that Māori in the New Zealand community have an increased rate of bipolar disorder. METHOD: The standardized recordings of a variety of clinical phenomena previously collected in a New Zealand study of psychiatric service users was extracted for those persons who were diagnosed with a bipolar mental disorder. The individual clinical phenomena were then compared by ethnicity. RESULTS: The most dramatic result was the increased recording of high levels of overactivity or disruptive aggressive behaviour in Māori compared with European in psychiatric service users, despite which, the rates of the disorder did not significantly differ by ethnicity. CONCLUSION: In the community survey lay raters were deciding on the presence or absence of phenomena including hyperactivity without the contextual knowledge that clinicians use. It is possible that the Composite International Diagnostic Interview decision tree was being fed an excessive amount of that criterion.  相似文献   
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The radioligand 2-[(18)F]fluoro-A-85380 has been developed for imaging alpha(4)beta(2) nAChRs with PET. However, it has slow kinetics and a large fraction of bound activity is nondisplaceable. In an attempt to address these problems, two epibatidine-based alpha(4)beta(2) nicotinic antagonists, coded FPhEP and F(2)PhEP, were evaluated in vivo in baboons. They were radiolabeled with fluorine-18 from the corresponding N-Boc-protected bromo-derivatives and the no-carrier-added K[(18)F]F-Kryptofix(222) complex. Radiochemically pure [(18)F]FPhEP or [(18)F]F(2)PhEP was obtained in 80 min in amounts of 1.11-2.22 GBq (111-185 GBq/micromol). After injection of 215 MBq of [(18)F]FPhEP or [(18)F]F(2)PhEP, dynamic PET data were acquired. Thalamic radioactivity peaked at 20 min (4.9% +/- 0.2% ID/100 mL tissue) for [(18)F]FPhEP. For [(18)F]F(2)PhEP, the peak was at 45 min (3.3% +/- 0.1% ID/100 mL tissue). Regional distribution of both radiotracers was in accordance with the known distribution of nAChRs. In presaturation experiments, nicotine, cytosine, or FPhEP reduced brain radioactivity of [(18)F]FPhEP. In a displacement experiment with nicotine only a small amount of [(18)F]F(2)PhEP was dislodged. In spite of a moderate to high in vitro affinity, both ligands do not fulfill the widely adopted criteria for a PET radioligand.  相似文献   
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PURPOSE: To analyze and compare spectral properties and interdependencies of intracerebral EEG signals recorded during interictal periods from mesial temporal lobe structures in two groups of epileptic patients defined according to the involvement of these structures in the epileptogenic zone (EZ). METHODS: Interictal EEG activity in mesial temporal lobe (MTL) structures (hippocampus, entorhinal cortex and amygdala) was obtained from intracerebral recordings performed in 21 patients with drug-resistant mesial temporal lobe epilepsy (MTLE group). This group was compared with a "control" group of patients (non-MTLE group) in whom depth-EEG recordings of MTL show that seizures did not start from the MTL. Comparison criteria were based on spectral properties and statistical coupling (nonlinear correlation coefficient h(2)) of MTL signals. RESULTS: Power spectral density analysis showed a significant decrease in the theta frequency sub-band (p=0.01) in the MTLE group. Nonlinear correlation (h(2)) values were found to be higher in the MTLE group than in the NMTLE group (p=0.0014). This effect was significant for theta, alpha, beta and gamma frequencies. Correlation values were not correlated with the frequency of interictal spikes (IS) and significant differences between groups were still measureable even when spikes were suppressed from analyzed EEG periods. DISCUSSION: This study shows that, during the interictal state, the EZ in MTLE is characterized by a decrease of oscillations in the theta sub-band and by a general increase of signal interdependencies. This last finding suggests that the EZ is characterized by network of neuronal assemblies with a reinforced functional connectivity.  相似文献   
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A potentially traumatic event (PTE) contributes to trauma through its frequency, conditional probability of posttraumatic stress disorder (PTSD), and experience of other PTEs. A cross-sectional survey was conducted, enrolling 21,425 adults nationally representative of six European countries. Using the WHO-Composite International Diagnostic Interview, 8,797 were interviewed on 28 PTEs and PTSD. Prevalence of 12-month PTSD was 1.1%. When PTSD was present, the mean number of PTEs experienced was 3.2. In a multivariate analysis on PTEs and gender, six PTEs were found to be more traumatic, and to explain a large percentage of PTSD, as estimated by their attributable risk of PTSD: rape, undisclosed private event, having a child with serious illness, beaten by partner, stalked, beaten by caregiver.  相似文献   
47.

Introduction

Phytoestrogens are a group of compounds found in plants that structurally resemble the hormone oestradiol, and thus have the potential to act as oestrogen agonists or antagonists. Their potential effects may alter the risk of breast cancer, but only a limited range of phytoestrogens has been examined in prospective cohort studies.

Methods

Serum and urine samples from 237 incident breast cancer cases and 952 control individuals (aged 45 to 75 years) in the European Prospective into Cancer-Norfolk cohort were analysed for seven phytoestrogens (daidzein, enterodiol, enterolactone, genistein, glycitein, o-desmethylangolensin, and equol) using liquid chromatography/mass spectrometry. Data on participants' diet, demographics, anthropometrics, and medical history were collected upon recruitment. All models were adjusted for weight, fat and energy intake, family history of breast cancer, social class, analytical batch, and factors related to oestrogen exposure.

Results

Urinary or serum phytoestrogens were not associated with protection from breast cancer in the European Prospective into Cancer-Norfolk cohort. Breast cancer risk was marginally increased with higher levels of total urinary isoflavones (odds ratio = 1.08 (95% confidence interval = 1.00 to 1.16), P = 0.055); among those with oestrogen receptor-positive tumours, the risk of breast cancer was increased with higher levels of urinary equol (odds ratio = 1.07 (95% confidence interval = 1.01 to 1.12), P = 0.013).

Conclusion

There was limited evidence of an association between phytoestrogen biomarkers and breast cancer risk in the present study. There was no indication of decreased likelihood of breast cancer with higher levels of phytoestrogen biomarkers, but the observation that some phytoestrogen biomarkers may be associated with greater risk of breast cancer warrants further study with greater statistical power.  相似文献   
48.
BACKGROUND/AIMS: Cirrhosis of the liver is characterized by glucose intolerance and hyperinsulinemia. Both increased insulin secretion and decreased insulin clearance appear to contribute to hyperinsulinemia in cirrhotic patients. A decrease in hepatic insulin extraction rate may be due either to hepatocellular dysfunction or to portosystemic shunting with decreased first-pass insulin clearance. METHODS: To specifically address the contribution of portosystemic shunting to the pathogenesis of hyperinsulinemia in cirrhotic patients, we analyzed glycemic control and insulin levels in fasting serum in 23 cirrhotic patients before and after transjugular intrahepatic portosystemic shunt (TIPS). RESULTS: Compared to respective values in healthy controls, C-peptide, insulin and proinsulin concentrations at baseline were increased by 340%, 120% and by 100% in cirrhotic patients (all p<0.05). In cirrhotic patients insulin levels before TIPS averaged 104+/-73 pmol/l and increased by more than 50% to 163+/-118 pmol/l after TIPS (p<0.01), whereas levels of C-peptide and proinsulin showed no significant change. Glucose and fructosamin levels also remained unchanged after TIPS. CONCLUSION: Our data demonstrate that TIPS does not impair glycemic control in cirrhotic patients and that an increase in portosystemic shunting augments hyperinsulinemia, most likely by decreasing hepatic insulin clearance.  相似文献   
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Background: Breast cancer is the leading cause of cancer death in women in Algeria. The contribution of BRCA1 and BRCA2 mutations to hereditary breast/ovarian cancer in Algerian population is largely unknown. Here, we describe analysis of BRCA1 and BRCA2 genes in 86 individuals from 70 families from an Algerian cohort with a personal and family history suggestive of genetic predisposition to breast cancer. Methods: The approach used is based on BRCA1 and BRCA2 mutations screening by High-Resolution Melting (HRM) curve analysis followed by direct sequencing. All samples for which no pathogenic mutation was found were analyzed by MLPA for large deletions or duplications. Results: Three distinct pathogenic mutations c.83_84delTG, c.181T>G, c.798_799delTT and two large rearrangements involving deletion of exon 2 and exon 8 respectively, were detected in BRCA1 gene. Moreover 17 unclassified variants and polymorphisms were detected in BRCA1 gene (6 described for the first time). Two pathogenic mutations, c.1310_1313delAAGA and c.5722_5723delCT and 40 unclassified variants and polymorphisms (14 never described before) were identified in BRCA2 gene. Conclusions: For the first time, we used HRM and MLPA to identify BRCA1 and BRCA2 mutations in Algerian patients with a personal and family history suggestive of genetic predisposition to breast cancer. The implications of these new findings in regard to genetic testing and counseling are substantial for the Algerian population.  相似文献   
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