[Effect of CIDR, eCG and artificial insemination on conception rate and lambing rate in Zell ewes]

Use of different estrus synchronization protocols and artificial insemination methods made variations in fecundity of Iranian Zell ewes. The purpose of the present study was to investigate pregnancy and lambing rates in Zell breed ewes following diverse progesterone treatment durations, eCG treatment doses and artificial insemination by transvaginal and/or laparoscopy methods. 180 cyclic, multiparous Iranian Zell ewes 45.5 +/- 2.5kg, were used in this experiment. The ewes were allocated randomly to 3 different groups [n = 60]. Estrus was synchronized using CIDR for 10 [A group], 12 [B group] and 14 [C group] days. At CIDR removal time, the ewes in each group was assigned into 3 subgroups [n = 20 and received eCG [0, 400 and 500 IU], respectively. 54 hours after CIDR removal, the ewes in each subgroup was randomly divided into 2 equal groups [n=10] and inseminated by transvaginal and laparoscopy, respectively. While combination of eCG treatment and CIDR removal increased pregnancy rate in all groups, the number of estrus have been augmented only in A and B groups. The artificial insemination by laparoscopy method made higher pregnancy and lambing rate compared to transvaginal technique. 500 IU eCG administration simultaneous with CIDR removal and artificial insemination by laparoscopy exhibited the best performance for pregnancy and lambing rate in Iranian Zell ewes

Bone marrow-mesenchymal stem cells as a suitable model for assessment of environmental pollution

Stem cells are considered as ideal model for assessment of environmental toxins on proliferation, multipotency and differentiation. The aim of this study was to investigate the effect of lead as harmaful environmental pollutant on proliferation and neural differentiation of murine bone marrow-MSCs. In this experimental study, MSC cells were exposed to different concentrations of lead [0 to 100 micro M] for 24h, and the level of cell proliferation was determined by 3-[4, 5-dimethyl-2-thiazolyl]-2, 5-dipheny-2H-tetrazolium bromide [MTT] reduction assay. In addition, DNA fragmentation was evaluated with comet assay at a single cell level. To induce the neural phenotype, MSCs were cultured for 2 days in the presence of 50 micro Pb[2+] for 48 h. At the end of this period, the medium was replaced by fresh medium supplemented with 1 mM beta-ME for 24 hr and then fresh medium supplemented with 7 mM beta-ME for 4 hours respectively. The expression of neural marker such as nestin, MAP2, and tau was assessed by immunocytochemistry, while the expression of neuronal specific genes such as Neur-1, Nestin, and beta-tubulin III was determined by RT-PCR analysis. Exposure to lead reduced the level of cell proliferation in a dose-dependent manner. The comet assay of cells exposed to lead showed varying degrees of DNA damaged. Change in cell morphology was observed 1 to 4 hr post neural exposure. The percentage of the MAP2 positive cells was reduced significantly at greater than 40 micro M lead concentration. This observation was further verified by assessment of the expression of neural markers. This study clearly indicated lead is highly cytotoxic to MSCs and these cells appear to be an excellent choice for establishment of guidelines for environmental hazards and drugs on cell proliferation and differentiation

[Corneal endothelial cell evaluation in donors with aluminum phosphide intoxication]

To evaluate corneal endothelial cells of donors who died from aluminum phosphide intoxication. Endothelial cell count and quality of eight corneas from four donors with aluminum phosphide intoxication were evaluated by slit lamp biomicroscopy and specular microscopy at the Eye Bank of I.R. Iran. Confocal scan examination was carried out only in one of the recipients. Donor age ranged from 21 to 60 years. All corneas were clear and the estimated endothelial cell density was very good to excellent. The endothelial cell density ranged from 2600 to 3300 cell/mm2 with a mean of 2920 cell/mm2. The pleomorphism ranged from 33% to 50% with mean of 40% and the polymegathism ranged from 31% to 39% with mean of 35%. In one recipient, 5 months after penetrating keratoplasty, the endothelial cell density was 2848 cells/mm2 on confocal scan with 40.8% polymegathism and 44.9% pleomorphism. Oral intoxication with aluminum phosphide seems not to affect corneal endothelial cell count and viability. Further experimental study is suggested