Street children in Tehran and risk factors for substance abuse

Present study has been conducted with the purpose of determining substance abuse style for street children in Tehran. 576 street children of 10-19 years were evaluated. Data were gathered by demographic and substance use check list. Theses check lists were designed by the researchers and included some simple question about type and duration of substance use. Several psychiatrist confirmed the content of check list. 36.7% of the children had lifetime smoking of cigarette. The frequency of smoking in boys was significantly higher than girls [P<0.05]. The mean age of the girls with smoking habit was significantly lower than the boys [P<0.05]. It should be noted that street children are at high risk group for using tobacco. Theses children are also exposed to the dangerous behaviors and sexually transmitted diseases

Epigenetic and genetic aberrations of the brain dopaminergic system in schizophrenia and bipolar disorder: Achievements and prospective

The molecular mechanisms of the fact that more than 50% of the individuals with the same genetic make up [e.g. identical twins in schizophrenia] do not show the same psychiatric phenotype remained undefined in psychiatry. This along with the failure to find responsible genes with major effects in psychiatric disorders and lack of consistency of genetic association studies led to the current unanimous conclusion that, in addition to the genetic factors, environmental and epigenetic factors influence the functions of brain and the presentation of the symptoms in mental diseases. Here we reviewed the potential epigenetic dysregulations of genes related to dopaminergic [DAergic] system. A comprehensive genetic and epigenetic analysis of the DAergic and the interacting pathways such as serotoninergic and glutaminergic systems could help to understand the molecular bases of the differences in disease severity in individuals with similar or identical genetic make-up that can assist for the identification of novel targets with therapeutic and preventive applications

detection of dopamine gene receptors [DRD[1]-DRD[5]] expression on human peripheral blood lymphocytes by real time PCR

There is interrelationship between the immune and nervous systems that is accomplished by the molecular mediators. Dopamine is one of the most important neurotransmitters. Five different dopamine receptor genes [DRD1, DRD2, DRD3, DRD4, and DRD5] have been recognized and cloned. The expression of the dopamine receptors is well characterized in the brain but little work has been done to examine their expression in other organ tissues. In certain diseases of the immune and nervous systems, alterations in dopamine receptors gene expression in different cells have been reported. This suggests that dopamine and its receptors have important role in pathophysiology of above-mentioned diseases. In the present study, using Real Time Polymerase Chain Reaction [PCR] technique, we investigated dopamine receptors genes expression in PBMC of normal individuals. The PBMC was separated from normal whole blood by Ficoll-hypaque; the total cellular RNA was then extracted and the cDNA was synthesized. This process followed by real time-PCR using primer pairs specific for five dopamine receptors mRNAs and beta-actin as internal control. The results showed the presence of all types of dopamine receptors in lymphocytes of normal individuals. The specificities of the obtained PCR products for the respective dopamine receptors fragments were confirmed by sequenced analysis capillary system. In conclusion, the present study has shown that human lymphocytes express five dopamine receptors DR1-DR5. However, the conclusive evidence on the possible function of these receptors in lymphocytes remains unknown. Because lymphocytes express all of the five neuronal dopamine receptors, it is quite reasonable to consider them as a model of dopaminergic neuron