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21.
It has been postulated that drugs of abuse act synergistically with HIV, leading to increased neurotoxicity and neurocognitive impairment. The CNS impacts of HIV and drug use converge on the mesocorticolimbic dopamine (DA) system, which contains two main receptor subtypes: dopamine receptors 1 (DRD1) and 2 (DRD2). DRD1 and DRD2 have been linked to substance dependence; whether they predict HIV-associated neurocognitive disorder (HAND) is unclear. Using an advanced-stage HIV+ population, we sought to determine if drug dependence impacts the contribution of DA receptor polymorphisms on neurocognition. We observed that both DRD1 and DRD2 polymorphisms were associated with opiate and cocaine dependence (P?<?0.05) in Caucasian subjects, but not African-American individuals. Using linear regression analysis, we examined the polymorphisms for associations with neuropsychological performance in global and cognitive domain T-scores (Motor, Processing Speed, Verbal Fluency, Learning, Memory, Executive Functioning, Working Memory) while controlling for opiate and cocaine dependency. In the Motor domain, we observed an association for two DRD2 polymorphisms (P?<?0.05) in Caucasian subjects. The effects differed for substance dependence groups as the direction of the correlations with DRD2 were opposite to what was seen in subjects without these dependencies. In African-American subjects, associations were observed in nearly every domain, and again, the direction of the correlation differed between substance-dependent and substance-independent groups. We conclude that studies to examine genetic risk for HAND must carefully account for substance dependence patterns when assaying dopaminergic systems, as the neurobiological substrates of cognition in HIV populations may vary with tonic alterations secondary to chronic substance exposures.  相似文献   
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Curcumin, the yellow spice derived from the roots (rhizomes) of the plant Curcuma longa, has been reported to have a chemoprotective effect against several neoplasms. The protective effect of curcumin during N-nitrosodiethylamine- and carbon tetrachloride-induced hepatocarcinogenesis in Sprague–Dawley rats and its effect on the expression of IkappaB-alpha mRNA were evaluated. Sixty male rats were randomly assigned into four experimental groups. Group A animals received a single i.p. injection of N-nitrosodiethylamine (200 mg/kg b.w.). After 1 week, the animals received weekly s.c. injections of carbon tetrachloride (3 ml/kg b.w./week) for 6 weeks. Group B was given diet containing 0.2 % curcumin 2 weeks before the injection of N-nitrosodiethylamine and continued throughout the experimental period (20 weeks). Group C was given only a diet containing 0.2 % curcumin for the whole period of the experiment. Group D animals served as control. The level of IkappaB-alpha (IкB-α) mRNA was determined by semiquantitative PCR. Administration of diet containing 0.2 % curcumin, 2 weeks before the injection of N-nitrosodiethylamine and throughout the period of experiment, decreased percentage of preneoplastic foci in hepatic parenchyma and inhibited the development of hepatocellular carcinoma, cholangiofibrosis, and cystic cholangioma in rat liver. Moreover, curcumin administration decreased the number and size of the preneoplastic foci induced by N-nitrosodiethylamine and carbon tetrachloride in the liver. The densitometric analysis of the IкB-α mRNA bands revealed that curcumin administration blocked the decrease of IкB-α mRNA induced by N-nitrosodiethylamine and carbon tetrachloride. These results concluded that curcumin inhibited hepatocarcinogenesis induced by N-nitrosodiethylamine and carbon tetrachloride through blocking IкB-α degradation.  相似文献   
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International Journal of Mental Health and Addiction - There is an urgent need to assess the impacts of the Coronavirus-19 disease (COVID-19) outbreak on mental health among the general population...  相似文献   
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The aim of this study was to report an unusual case of mucoepidermoid carcinoma (MEC) in a 39-year-old woman. The tumor showed a prominent population of clear and intermediate basal cells. Clear cells rarely predominate over other cell types. Such cases are called clear cell variant of MEC. The case also revealed a variable amount of calcified material in the tumor mass. Calcifications are rare in clear cell MEC. These structures were periodic acid-Schiff positive and diastase resistant, excluding glycogen origin. Immunohistochemistry was performed, and the epidermoid component was positive for cytokeratin (CK)7, CK13, CK14, and CK19. The mucous and clear cells presented mild staining for CK7. Cytokeratins 7, 13, and 19 stained luminal cells, and intermediate cells exhibited positivity for CK7, CK14, and vimentin. The origin of the calcifications is speculated to be the result of dystrophic calcification of the amorphous eosinophilic material secreted by intermediate basal cells.  相似文献   
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Objectives. This study examined the psychometric properties of the Multidimensional Fatigue Symptom Inventory-Short Form (MFSI-SF) in a community-based sample of African-Americans.

Design. A sample of 340 African-Americans (116 men, 224 women) ranging in age from 18–81 years were recruited from the community (e.g., churches, health fairs, and beauty salons). Participants completed a brief demographic survey, the MFSI-SF and the Positive and Negative Affect Schedule.

Results. The structural validity of the MFSI-SF for a community-based sample of African-Americans was not supported. The five dimensions of fatigue (General, Emotional, Physical, Mental, Vigor) found for Whites in prior research were not found for African-Americans in this study. Instead, fatigue, while multidimensional for African-Americans, was best represented by a unique four-four profile in which general and emotional fatigue are collapsed into a single dimension and physical fatigue, mental fatigue, and vigor are relatively distinct. Hence, in the absence of modifications, the MFSI-SF cannot be considered to be structurally invariant across ethnic groups. A modified four-factor version of the MFSI-SF exhibited excellent internal consistency reliability and evidence supports its convergent validity. Using the modified four-factor version, gender, and age were not meaningfully associated with MFSI-SF scores.

Conclusion. Future research should further examine whether modifications to the MFSI-SF would, as the findings suggest, improve its validity as a measure of multidimensional fatigue in African-Americans.  相似文献   

28.
The association between international and domestic migration and alcohol use among indigenous communities is poorly understood. We explored migration-related factors associated with alcohol use behaviors among an indigenous Mayan, binational population. From January to March 2012, 650 indigenous participants from the high-emigration town of Tunkás in the Mexican state of Yucatán (n = 650) residing in Mexico and California completed surveys. Multivariate logistic regression identified migration-related factors associated with alcohol use behaviors. US migration of shorter duration (<5 years) was independently associated with at-risk drinking (adjusted odds ratio (AOR) 2.34; 95 % confidence interval (CI) 1.09–5.03), as was longer-duration domestic migration (≥5 years) (AOR 2.34; 95 % CI 1.12–4.87). Ability to speak Maya (AOR 0.26; 95 % CI 0.13–0.48) was protective against at-risk drinking. Culturally appropriate alcohol use prevention interventions are needed for domestic and international indigenous Mexican migrants to address alcohol use behavior in the context of migration.  相似文献   
29.
Epidepride is a benzamide with high affinity for central D2- and D3-dopamine receptors. The anatomical distribution of [125I]epidepride binding was examined by autoradiography, using postmortem human whole-hemisphere cryosections. The density of [125I]epidepride binding sites was high in caudate nucleus and putamen. [125I]epidepride also labeled receptors in extrastriatal region such as in the pallidum, some thalamic nuclei, the neocortex, and the substantia nigra. The neocortical binding was heterogeneously distributed. In most cortical regions, binding sites were located in superficial layers (I-II). However, in basal levels of the occipital cortex, [125I]epidepride binding was located in a deeper layer, probably corresponding to layer V. Competition studies indicated that most of the [125I]epidepride binding represented predominantly D2-dopamine receptors, in striatal as well as in extrastriatal regions. The presence of extrastriatal D2-dopamine receptor populations is of particular interest for research on schizophrenia and antipsychotic drug action. © 1996 Wiley-Liss, Inc.  相似文献   
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