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  Background & Objectives : Several studies have been conducted to explore anti-HIV drugs. Discovery and study of novel anti-HIV-1 compounds need live viruses and has serious biosafety concerns. In this research we reported a novel and safe system for assaying the cytopathic effects of HIV by using single cycle replicable (SCR) HIV-1 virions.

  Methods: To produce the SCR HIV-1 virions, pMD2G, pmzNL4-3 and pSPAX2 plasmids were co-transfected into HEK293T cells. Different amount of SCR virions were used to infect target cells (MT-2). Within the infected cells, the number of formed syncytia was counted under the light microscopy. The lethal effects of the SCR HIV virions were measured using XTT proliferation assay.

  Results: Formation of syncytia among SCR HIV infected cells was detectable 24 hours after infection. Highest amount of syncytia was seen 72 hours after infection. Increase in the amount of virions caused increasing of syncytia and the cytopathic effects of SCR HIV-1. Infection with more than 1600ng P24 SCR HIV decreased the syncytium formation and viability of all cells. The calculated IC50 (50 percent inhibitory capacity) for nevirapine and BMS806 using this method was 50nM and 30nM, respectively.

  Conclusion: SCR HIV-1 virions are replicable only for one cycle. Using these virions can improve the safety of HIV researches. Herein, we optimized the assaying of HIV induced cytopathic effects by using SCR HIV-1 (NL4-3) virions. The accuracy of this method was accepted by quantifying the anti-HIV-1 effects of nevirapine and BMS806 by (SCR) HIV-1 virions.

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Background & objectives: Toxoplasma gondii is a zoonotic obligate intracellular protozoan parasite that infects all warm-blooded animals as well as human worldwide. Determining the parasite genotype in intermediate hosts  is crucial in  evaluating the role of these types in human infections as wll as in prevention programs. Therefore, this study aimed to identify and detect the genotypes of Toxoplasma gondii in aborted fetuses of ewes in Lorestan province.
Methods: Identification of the parasite was performed  on the brain and liver tissues of 142 aborted fetuses using  a conventional PCR based on amplification of highly repetitive 529 bp region of the parasite genome. Genotyping of positive samples, which were isolated from the brain and liver, was performed by PCR-RFLP based on SAG2, SAG3 and GRA6 molecular markers.
Results: From a total of 142 samples  obtained from  brain  and fetus, 10 cases (7%) were determined as positive samples based on conventional PCR. The precence of parasite DNA was also confirmed in the liver of  3 positive samples. Evaluation of RFLP pattern of amplified SAG2, SAG3 and GRA6 genes showed the presence of various types of parasites, incuding type I in 3 samples, type II in 2 samples and atypical type in 5 samples.
Conclusion: Isolation of types I, II and atypical type of T. gondii from ewes in  Lorestan province suggests the need for greater attention to parasite transmission from livestock to human, particularly in pregnant women and people with weakened immune system.