نشریه زیست فناوری دانشگاه تربیت مدرس
پیاپی 1 (پاییز 1389)

Multiple sclerosis (MS) is commonest demyelinating disease among young adults. It demonstrates neurological dysfunctions in females more than males. Gonadal hormones have essential roles in maturation and differentiation of neurons and glial cells in both genders. The role of some gonadal female hormones such as progesterone has been well characterized on demyelination and remyelination in animal models. The role of androgens on neural system development and myelin maturation were identified. We previously observed that castration decreases the brain resistance against demyelinating insults and also reduces the subsequent repair. As the optic nerves and chiasm demyelination shows the hallmark characteristic in MS, inducing demyelination in optic apparatus, we have tried to find whether the effects of elimination of male gonadal hormones using gonadectomy could show the same, more or less changes in patterns of demyelination and repair comparing demyelinated females? Thus, to evaluate these alternations castrated male and female rats were compared by using visual evoked potentials and histological assessments on 2,7,14, and 28 days post lysolecithine (LPC) injection. Interestingly, we observed demyelination was started 2 day post lesion (dpl), reached to a maximum level at 7 and 14 dpl and then it partially but significantly reversed on 28 dpl. Demyelination and subsequent repair processes in both gonadectomized and female groups were shown almost the same patterns temporarily and in quality. Elimination of gonadal androgens could cause the male animals to undergone the same shape of de/remyelination compared female ones. In conclusion, differences between male and female demyelination and remyelination are substantially depending on male gonadal androgens. This work could be useful for understanding of the effects of sex hormones on demyelinating diseases and could offer fundamental information for repairing therapies in Multiple Sclerosis.

Lentiviruses are considered one of the most effective recombinant viruses for gene transfer to mammalian cells and tissues. In this study, the potential of HIV-1-based lentiviral vector to deliver transgenes into avian cells was examined. We co-transfected human embryonic kidney cell line HEK-293T with three lentivirus vectors called transfer, packaging and envelope vectors. We collected the supernatant from transfected cells 24 and 48 hours post-transfection and filtered them immediately. Then we subjected the filtered supernatant to Amicon protein columns for concentration purposes. Centrifugation removed a larger part of the supernatant presumably free of viruses and left behind a small volume of darken solution full of virions. We thereby produced a 500-µl-volume of virus stock. Various dilutions of this stock were added to chicken liver cell line LMH. The initial sign of infection appeared within 48 hours and by 96 hours post-infection 100% the LMH cells positively expressed transgenes. Our results indicated that the human HIV-1-based lentivirus vectors are capable of transducing and transferring foreign genes into chicken cells. Given the need for a high-titer virus stock for successful target cell transduction, our results indicate that the filtration method of virus concentration is able to produce high virus titer and is cost-effective and less time consuming than ultracentrifugation or other traditional methods.

Evaluation of Liver Enzymes’ Level in Blood Serum of Crystal Addicts

Crystal or dimetamphetamine is one of the harmful substances which are imported to Iran in the last few years. Crystal is made of pure heroin. Its harmful effects are more than heroin. Addiction to crystal can produce psychological and organ damage. In order to find out which part of body could be affected, examination of enzymes is useful. Liver is one of the organs which can be infected by drug abuse. Liver function test can be used to show these harmful effects. The aim of the present study is to exanimate of the effects of crystal abuse on liver enzymes such as Aspartat transaminase, Alanine transaminase and Alkaline phosphatase in crystal abusers.

The current study is a case-control and cross-sectional study on 105 crystal addicted as case group who had referred to addiction treatment center for the first time and 100 healthy people as control group. The activity of enzymes was measured by callorimetery-spectrophotometry method. Results were analyzed by T-test exam and SPSS-16 software.

results show that using crystal increases the level of AST, ALT and ALP and there is a significant relationship between crystal abuse and the level of ALP (p=0.027). In addition, there is a significant relationship between duration of crystal use and the level of ALP (p<0.05).

comparing with AST and ALT levels, ALP level is more affected by crystal abuse.