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991.
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This review deals with the results showing the relation between vitamin B(12) deficiency and neurotoxicity of homocysteine and nitrite (a metabolite of nitric oxide) in Parkinson's patients treated with levodopa (L-Dopa). We have already reported a linear relationship between the CSF levels of nitrite with glutamic acid and homocysteine suggesting that the production of nitrite is interrelated with the neurotoxic level of homocysteine. The levels of nitrite and homocysteine resulting in the deficiency of vitamin B(12) are some of the factors promoting degeneration in Parkinson's disease. This review emphasizes the importance of these parameters in designing suitable drug therapy for Parkinson disease. Additionally, there is evidence that increased homocysteine levels might accelerate dopaminergic cell death in Parkinson disease (PD), through neurotoxic effects. Furthermore, levodopa (L-Dopa) treatment of PD results in hyperhomocysteinemia as a consequence of L-Dopa methylation by catechol-O-methyltransferase (COMT). Therefore, higher dietary intakes of folate, vitamin B12, and vitamin B6 might decrease the risk of PD through decreasing plasma homocysteine.  相似文献   
993.
Cotard's syndrome is a rare syndrome, characterized by the presence of nihilistic delusions. The syndrome is typically related to depression and is mostly found in middle-aged or older people. A few cases have been reported in young people with 90% of these being females. We present a case of a young pregnant woman suffering from Cotard's syndrome. This is the first report of this syndrome in a pregnant woman. The case was diagnosed late, due to lack of awareness of psychiatric problems in primary care physicians resulting in undue suffering, loss of precious time and resources for the patient. Besides highlighting the rare combination of pregnancy and Cotard's syndrome this report delineates the difficulties faced by patients with such symptoms in a low resource setting.  相似文献   
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Tardive dyskinesia (TD), a syndrome of involuntary hyperkinesias in the orofacial region that develops in patients chronically treated with neuroleptic agents is a major limitation of the therapy. Rats chronically treated with haloperidol exhibit vacuous chewing movements (VCMs) with the twitching of facial musculature and tongue protrusion. The syndrome is widely used as an animal model of TD. Evidence suggests a role of 5-hydroxytryptamine (5-HT; serotonin)-1A receptors in the pathogenesis and treatment of TD because repeated administration of haloperidol resulted in an increase in the effectiveness of 5-HT-1A receptors while drugs with agonist activity at 5-HT-1A receptors could attenuate haloperidol-induced VCMs. The present study was designed to test the hypothesis that a decrease in the responsiveness of somatodendritic 5-HT-1A receptors by the coadministration of buspirone could reverse the induction of VCMs and supersensitivity at 5-HT-1A receptors by haloperidol. Rats treated with haloperidol at a dose of 1 mg/kg twice a day for 2 weeks displayed VCMs with twitching of facial musculature that increased in a time dependent manner as the treatment continued to 5 weeks. Coadministration of buspirone attenuated haloperidol-induced VCMs after 2 weeks and completely prevented it after 5 weeks. The intensity of 8-hydroxy-2-di (n-propylamino) tetralin (8-OH-DPAT)-induced locomotion was greater in saline+haloperidol injected animals but not in buspirone+haloperidol injected animals. 8-OH-DPAT-induced decreases of 5-HT metabolism were greater in saline+haloperidol injected animals but not in buspirone+haloperidol injected animals. It is suggested that an impaired somatodendritic 5-HT-1A receptor dependent response is a major contributing factor in the pathophysiology of TD and a normalization of the somatodendritic response by drugs may help extending therapeutics in schizophrenia.  相似文献   
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In 2003 the Thai government announced a radical shift in drug policy with the implementation of a War on Drugs. Although consequences of this controversial measure (e.g. drug dealer deaths) have received widespread attention relatively little work has evaluated changes in substance use. We used two anonymous representative samples of secondary school students to compare drug use in Northeast Thailand before (1998; n=4217) and after (2004/5; n=3489) the War on Drugs. Results indicate that reported levels of current illicit drug use reduced significantly between 1998 and 2004/5 (for methamphetamine from 4.2% to 0.9%). By examining trends in year of first methamphetamine use we identify that observed reductions in drug initiation are temporally consistent with the War on Drugs. However, while prevalence of alcohol use has also fallen, there was a three-fold increase in daily alcohol use. We suggest that this rise, combined with other negative impacts of 'wars' on drugs, means drug control requires a public health perspective that sees eliminating drug use as part of a wider strategy that has improvement in population health, not just drug prevention, as its core objective.  相似文献   
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