Tehran University Medical Journal

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A random panel of 500 healthy unrelated subjects from Isfahan province were HLA typed for A, B and C locus antigens. The lymphocytes were separated from 5 ml of whole peripheral blood and HLA-A, B, C typing were performed on them, using the standard two stage microlymphocytotoxic NIH technique. The antigens HLA-A1, A2, A3, A9, HLA-B5, B35, HLA-CW4 had the higher frequency than other HLA antigens among the population studied. The distribution of HLA class I antigens in Isfahan is similar with their distribution in Tehran and Mashhad.

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Obstructive cholestasis is associated with overproduction of endogenous opioids (EOP), nitric oxide (NO), and cytokins in the blood streams. Therefore we investigated the relationship between obstructive cholestasis and function of germ cells in adult male rats.
Material and Methods: To study this, we used three groups of animals: No-surgery, Sham-surgery, and surgical ligation of the bile duct. After 3 weeks all animal were killed by ether, serum concentrations of FSH, LH and testosterone were determined by Radioimmunoassay, apoptosis was evaluated by DNA fragmentation detected by in situ terminal deoxynucloetidyl Transfrase-mediated dUTP nike end labeling (TUNEL).
Results: The mean of FSH level in cholestatic, control and sham groups were 13.22+ 1.038, 18.14+ 1.276, and 16.92+ 1.072 ng/ml, respectively. The mean of LH level in cholestatic, control and sham groups were 0.83 + 0.21, 2.058 ± 0.26, and 1.84 + 0.17 ng/ml, respectively. In addition, the mean of testosterone level in cholestatic, control and sham groups were 1.52 ± 0.16, 2.41 ± 0.18, and 2.31 + 0.14 ng/ml, respectively. The results of this study were indicated that serum FSH, LH and testosterone were significantly lower in cholestatic than control and sham groups (p=0.0195, P= 0.0029, and P=0.0023, respectively). However there was no significant difference in apoptotic index between all of groups (P=0.195). The apoptotic index in cholestatic, control and sham rats were 9.897± 1.374, 7.086 + 0.91, and 7.729 + 1.101, respectively.
Conclusion: These findings have been shown which as obstructive cholestasis was decreased the levels of serum gonadotropins and testosterone but it has no significant effector testicular germinal cells apoptosis.

 

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Background: Hyaluronan has an important role on the permeability and motility of sperm and the interaction of gametes and these can play a considerable role on the fertility rate. Therefore, in this study, we assessed the effect of different doses of hyaluronan on the morphology, motility, vitality and fertility rate of mice.

Methods: We used 40 mice (6-8 week) in this study which twenty of them were male and the rest were female. The sperm of each male mouse were divided into four groups. The group 1 (control): They were maintained in RPMI media without any hyaluronan supplementation for 2 hour. Hyaluronan with the doses of 750, 1000 and 1250 µg/ml were added into RPMI media in groups 2, 3 and 4, respectively. After 2 hour. incubation, the numbers of sperms were assessed, using haemocytometer. Also, their morphology with papanicolaeu staining and their vitality with Eosin B dye were assessed. As well as sperms motility measured under inverted microscope by observation and fertility rate evaluated after routine IVF by counting two-cell stage embryos.

Results: Our results demonstrated that, the dose of 750 µ g/ml has the greatest effect on the motility, vitality and fertility rate of sperms. The effect of dose of 1000 µ g/ml also was positive on them. On the other hand, none of these doses had any effect on sperm morphology.

Conclusion: Hyaluronan may have an influence on motility, vitality and fertility rate of sperms and the dose of 750µ g/ml had a significant effect on these factors.

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Background: The aim of this study was to determine the level of lipid peroxidation and tissue protein after superior mesenteric artery occlusion tissue damage. The effect of melatonin as anti oxidant and free radical scavenger in prevention of tissue damage, were also evaluated.

Methods: Thity six young male Wisatr-Albino rats (weight: 80-120 gr), were divided equally in 6 group with different concentrations of melatonin (10,20,30 mg/kg) treatment. Group 1was control, group 2 the sham that surgical process was applied until superior mesenteric artery dissection and received vehicle solution only in equally volume by intra muscular route. Group 3 was ischemia- reperfusion (I/R), group 4 was I/R plus melatonin 10 mg/kg, group 5 I/R plus melatonin 20 mg/kg and finally group 6 I/R plus melatonin 30 mg/kg. After laparatomy, a microvascular atraumatic clip was placed across the superior mesenteric artery under general anaesthesia and itbremoved after ischemia for 30 minutes. The first dose of melatonin was applied just beforereperfusion, second dose, after reperfusion and third dose on the second day .On third day rats were killed and their bowels were removed. The level of tissue melandialdehyde (MDA) as index of lipid peroxidation and tissue protein was determined.

Results: The level of tissue MDA were significantly lower in group 4, 5, 6 than group 3 (p<0.05). Tissue protein levels were significantly upper in group 4 than group 3. (p<0.001). There was no significant difference tissue protein level in group 5, 6 than group 3(p>0, 05).

Conclusion: These results suggest that melatonin 10 mg/kg has antioxidant effect in prevention of inducing tissue damage during SMA occlusion in rat intestine.

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Background: Studying the behavior of a society of neurons, extracting the communication mechanisms of brain with other tissues, finding treatment for some nervous system diseases and designing neuroprosthetic devices, require an algorithm to sort neuralspikes automatically. However, sorting neural spikes is a challenging task because of the low signal to noise ratio (SNR) of the spikes. The main purpose of this study was to design an automatic algorithm for classifying neuronal spikes that are emitted from a specific region of the nervous system.

Methods: The spike sorting process usually consists of three stages: detection, feature extraction and sorting. We initially used signal statistics to detect neural spikes. Then, we chose a limited number of typical spikes as features and finally used them to train a radial basis function (RBF) neural network to sort the spikes. In most spike sorting devices, these signals are not linearly discriminative. In order to solve this problem, the aforesaid RBF neural network was used.

Results: After the learning process, our proposed algorithm classified any arbitrary spike. The obtained results showed that even though the proposed Radial Basis Spike Sorter (RBSS) reached to the same error as the previous methods, however, the computational costs were much lower compared to other algorithms. Moreover, the competitive points of the proposed algorithm were its good speed and low computational complexity.

Conclusion: Regarding the results of this study, the proposed algorithm seems to serve the purpose of procedures that require real-time processing and spike sorting.

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Background: Spermatogenesis is a complex and highly organized process of proliferation and differentiation of spermatogonial stem cells. Spermatogonial stem cells (SSCs) as a unique stem cell have the potential to self-renewal, differentiation and transmit genetic information to the next generation and play a vital role in maintaining fertility. Sertoli cells as the only somatic cells within the seminiferous epithelium play central roles in the formation of niche and balance between self-renewal and differentiation by secrete many growth factors. Given the importance and widespread use of SSCs, particularly in the treatment of infertility, the aim of this study was to create an optimal environment for the proliferation of SSCs. So we decided to study of undifferentiated (ID4) and differentiated (c-Kit) gene expression in SSCs followed by co-culture with Sertoli cells for a one-month.

Methods: This experimental study was conducted from November 2013 to December 2014 in Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, on immature NMRI mouse (6-3 days old). Initially, Sertoli cells and SSCs were isolated from neonates mouse testes during the two-step enzymatic digestion characteristics Sertoli cells with vimentin marker and SSCs with promyelocytic leukemia zinc-finger (PLZF) marker were confirmed. Then SSCs were cultured in two groups: co-culture with Sertoli and without co-culture (control). Undifferentiated (ID4) and differentiation (c-Kit) gene expression were evaluated by Real-time PCR technique.

Results: Spermatogonial stem cells purity was obtained 66.91% by flow cytometry. The relative expression levels of gene ID4 in co-culture group at the end of each week, compared to the control group showed a significant increase (P<0.05). While the expression of this gene significantly decreased in each group over time (P<0.05). The results of the comparison of the relative expression of c-Kit gene in co-culture group are indicated significant decrease than the control group at the end of each week (P<0.05). In addition, this gene expression was showed significant increase in each group individually over time (P<0.05) ID4 gene expression showed a significant (P<0.05) increase toward the control group, while in the expression of c-Kit was observed a significant (P<0.05) decrease compared with the control group at the end of each week.

Conclusion: According to the results of this study, co-culture with Sertoli cells maintains SSCs in the prolifration stage for long-term, so can be used to optimize the culture medium at the clinic.

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