Risperidone is an atypical antipsychotic agent with efficacy for both positive and negative symptoms of schizophrenia. However, what makes an antipsychotic 'atypical' remains unclear. We recently found that the T102C polymorphism in the 5-HT2A receptor gene could affect risperidone's efficacy for negative symptoms. The present study investigated the effect of the Ser311Cys polymorphism in the dopamine D2 receptor (DRD2) gene on risperidone treatment response. A total of 123 Han Chinese patients with acutely exacerbated schizophrenia were given risperidone for up to 42 days. Clinical manifestations were measured bi-weekly with Positive and Negative Syndrome Scale (PANSS) and Nurses' Observation Scale for Inpatients Evaluation (NOSIE, for assessment of social function). For adjusting the within-subject dependence over repeated assessments, multiple linear regression with generalized estimating equation methods was utilized to analyse the effects of Ser311Cys polymorphism and other covariates on clinical performance. Compared with patients who had the Ser311Ser genotype, patients with the Ser311Cys genotype had lower scores on PANSS Positive, Negative, General Psychopathology and Cognitive subscales and NOSIE, after adjustment for 5-HT2A T102C polymorphisms and other confounders. The 5-HT2A T102C polymorphism had marginal influences on PANSS Total and Negative subscale scores. Male gender, fewer previous hospitalizations, and higher risperidone dose predicted better treatment response after control for other variables. The preliminary results suggest that variations in the DRD2 gene influence risperidone treatment response for positive, negative, and cognitive symptoms, general psychopathology, and social functioning. Several clinical factors may also contribute to inter-individual differences in risperidone treatment response.

These observations argue that amygdala-kindling-induced sleep-wake alterations are modulated by central increases in CRH or IL-1.

FAAH-like anandamide transporter (FLAT) regulates anandamide transport for hydrolysis and may be an attractive drug target for pain regulation. We aimed to discover potential FLAT antagonists from traditional Chinese medicine (TCM) using virtual screening, ligand-based drug design and molecular dynamics simulation (MD). Guineensine and Retrofractamide A exhibited high Dock Scores in FLAT. Consensus from multiple linear regression (MLR; R2 = 08973) and support vector machine (SVM; R2 = 0.7988) showed similar bioactivities for Guineensine and the FAAH-1 inhibitor (9Z)-1-(5-pyridin-2-yl-1,3,4-oxadiazol-2-yl)octadec-9-en-1-one. Contour of Guineensine to CoMFA and CoMSIA features also imply bioactivity. MD revealed shake or vibration in the secondary structure of FLAT complexed with Guineensine and (9Z)-1-(5-pyridin-2-yl-1,3,4-oxadiazol-2-yl)octadec-9-en-1-one. Ligand movement might contribute to protein changes leading to vibration patterns. Violent vibrations leading to an overall decrease in FLAT function could be the underlying mechanism for Guineensine. Here we suggest Guineensine as a drug-like compound with potential application in relieving neuropathic pain by inhibiting FLAT.

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The clinical features of a patient in a Chinese family with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS syndrome) are reported. The study revealed that hearing and visual impairments and miscarriages may be early clinical presentations in MELAS. A heteroplasmic A to G transition in the tRNAIAu(uuR) gene was noted at the nucleotide pair 3243 in the mitochondrial DNA of muscle, blood, and hair follicles of the proband and his maternal relatives. Quantitative analysis of the mutated mitochondrial DNA revealed variable proportions in different tissues and subjects of maternal lineage in the family. Muscle tissue contained a higher proportion of the mutant mitochondria than other tissues examined. The function of the reproductive system of the proband seems to be impaired. In one clinically healthy sibling, the 3243rd point mutation was found in sperm mitochondrial DNA, although sperm motility was not affected. It seems that biochemical defects in mitochondrial respiration and oxidative phosphorylation are tissue specific expressions of the 3243rd point mutation in the mitochondrial DNA of the affected target tissues.

Nlybrominated dibenzo-p-dioxins (PBDDs) and dibenzolurans (PBDFs) occur as trace (ppb) contaminantsin brominated flame retardants and are produced during combustion ofthese chemicals. They are also formed when organics are incinerated in the presence ofbromine, e. g., in municipal and industrial incinerators and in internal-combustion engines. Combustion of organics in the presence of both bromine and chlorine results in the formation of mixed (ie., bromo, bromo/chloro and chloro) halogenated dibenzo-p-dioxins and dibenzofurans (HDDs and HDFs

Risperidone and other newer atypical antipsychotics are becoming the mainstay for schizophrenia treatment. Recent studies suggest that the 5-hydroxytryptamine receptor 2A (5-HT2A) gene (HTR2A) T102C and G-1438A polymorphisms may influence treatment response of risperidone or olanzapine for schizophrenia's negative symptoms (e.g., blunted affect and social withdrawal). In addition, the HTR6 T267C polymorphism has been linked to risperidone response for positive symptoms (delusions and hallucinations). The dopamine D2 receptor (DRD2) Ser311Cys polymorphism may also play a role in determining risperidone efficacy for positive, negative and cognitive symptoms, the DRD2 Ins-A2/Del-A1 diplotype may predict better risperidone response, and the DRD3 Ser311Cys variant may affect general treatment response of several atypical agents. Although investigators have started to explore genetic effects on cognitions of schizophrenia patients receiving antipsychotics, future larger sized pharmacogenetic studies on both psychotic symptoms and cognitive functions are warranted.