Anatomical Sciences Journal
Year:2004 | Volume:2 | Issue:1|Papers Count:9

Purpose: Yolk sac hematopoietic stem cells (YS-HSC) have two dominant characteristices: a larger reproductive capacity and the absence of the expression of MHC associated antigens. Therefore, these cells are promising candidates for transplantation, cell therapy and gene manipulation. There are controversial reports on the effects of erythropoietin (EPO) on the differentiation of yolk sac cells (YSC) to erythroid lineage in vitro.Materials and Methods: The yolk sacs were dissected from 10 - day - old NMRI mouse embryos and separated mechanically and enzyme digestions (0.1% collagenase or 0.25% trypsin/O.02% EDTA). The colony assay of these cells was performed in the presence of interleukin-3, stem cell factors and different dosages of EPO in a semisolid medium. A control group was also considered in the absence of EOP. After 14 days, benzidine staining on the colonies was carried out and positive benzidine colonies were counted as erythroid colonies. Also, the cytospine slides of those colonies were prepared and stained using benzidine and wright giemsa staining. There was not good result from direct culturing of yolk sac cells. So these cells were co-cultured on the bone marrow stromal cells as a feeder layer.Results: The results showed that in the presence and absence of EPO, the YSCs were differentiated to erythroid cells. However, the number of the positive benzidine colonies (55.4%) and the size of colonies in the presence of EPO (1 U/ml) were increased compared to the control group. There was no statistically significant difference between these groups. Co-culture of these cells with feeder layer also revealed that in the presence of EPO, a better differentiating effect could be observed.Conclusion: In conclusion, in vitro differentiation of YSCs to erythroid lineage was seen in the absence of EPO. However EPO could have a positive effect on the improvement of the erythroid colonies, it needs more investigation.

Purpose: We investigated the effect of (bFGF) (basic-Fibroblast Growth Factor) on the differentiation of divided cardiomyocytes from mouse embryonic stem cells (ES) and their pharmacological properties.Materials and Methods: The mouse embryonic stem cells (Royan B1) were cultured as 800 cells per 20µl of a hanging drop. After two days, ES cells in each drop aggregated to form embryoid bodies (EBs). The EBs were cultured in bacterial dishes for 5 days. In the first two days of culture in the bacterial dishes, the cells were treated with 10ng/ml bFGF.Then the EBs were plated in gelatin- coated 24-well plates individually, and the beating rates of the EBs were recorded in the control and bFGF groups no a daily basis.Moreover, the chronotropic effects of isoprenaline, carbachol and phenylephrine on ES cells-derived cardiomyocytes were investigated.Results: Treatment of cardiomyocytes with isoprenaline and phenylephrine, increased the rate of heart beat in both groups, but this rate was enhanced in early stages of development in the bFGF group more than that in the controls (p<0.035 and p<0.015). Furthermore, although, carbachol decreased the heart rate, this difference was not statistically different in both groups. The beating rate was higher in the EBs in the control group than that in the bFGF group (7+5 day with p<0.012, 7+7 day with p<0.002, 7+9 day with p<0.0001, 7+17 day with p<0.014, 7+19 day with p<.001 was significant). Also, the beating rate was found to the more stable in the control group.Conclusion: These results showed that although bFGF probably exerts its effects on the expression or function of some cardiomycytes receptors, individually it has no significant effect on cardiogenesis.

Purpose: Semen freezing is an important technique in human infertility treatment in many different patients but it damages sperms. Low-power lasers are physical agents that have biostimulatory effects. In this study, low-power helium-neon laser's (16J/cm2, one time irradiation) effect on motility and ultrastructure of fresh and frozen-thawed human sperm were studied.Materials and Methods: Thirty healthy men referring to Koassar Infertility Center in 2003 were chosen according to WHO's criteria. Semen samples were taken and divided into four different study groups. Sperm analysis was done before and after He-Ne laser irradiation, after thawing, and after irradiation on the thawed samples. Specimens were prepared for transmission electron microscopy (TEM) study. Sperm motility and its grades was analyzed using Wilcoxon test.Results: Semen cryopreservation signicantly decreased the motility of the sperms (p=0.0001). Laser had no effect on fresh semens but increased the motility rate of frozen-thawed semens significantly (p=0.033). TEM study revealed that after laser irradiation, nuclear envelope was not only irregular and in some parts disrupted, but was also away from nucleus together with acrosome. Freeze-thawing caused morphological abnormalities.Conclusion: Low power laser can increase sperm motility rate after freeze-thawing and may increase the fertility rate with frozen sperm.

Purpose: The nucleus raphe magnus (NRM) is a medullary nucleus containing serotonergic and non serotonergic neurons, both of which densely project to spinal cord. The goal of this study was to determine the role of these non serotonergic neurons in pain perception and their cytological changes after the specific lesion of bulbo-spinal serotonergic pathway.Materials and Methods: Male rats were intrathecally administered 5,6 Dihydroxytryptamine (5,6 DHT). Then animals were perfused 5, 14 and 30 days after the injection of neurotoxin or vehicle. Serial microtom sections (5-8 microns) were Nissl Stained, and the cytological changes of neurons were evaluated by light microscope.Results: The results revealed that the number of all three types of NRM neurons was significantly reduced following the intrathecal injection of 5, 6 DHT. The reduction was not recovered within one month, although; the pain perception returned to normal level. In addition, a significant enlargement (increase in long axis) was also observed in NRM neurons after the chemical lesions of descending 5-HT pathways (p<0.001).Conclusion: It is concluded that no evident recovery will be seen in serotonergic pathways after their select in destruction, although the pain perception becomes normal after one month. Normal threshold of pain indicates a probable function adaptation of other transmission systems, which compensates for the loss of serotonergic neurons.

Purpose: This Study evaluated the resumption of meiosis, in vitro maturtion and department of immature mouse oocytes with b- mercaptothanol.Materials and methods: Immature oocytes were recovered from NMRI mouse strain (4-6 weeks) in different 4 experiments groups: the control group, the oocytes were matured in MEM-a+ medium containing + FCS 55%; group 1: the oocytes were matured in MEM- a medium containing + FCS 5% and b-mercaptoethanol; group 2: the oocytes were matured in MEM-a+ FCS 5%, rFSH 100mIU and group 3: the oocytes were mature in MEM- a medium containing, FCS 5%, hCG 7.5IU, rFSH100mIU, b-mer-captoethanol 100 mm. Fertilization and embryo development were done in T6 medium.Results: There were significant differences on in vitro maturation between control group than the group 1 and group 3 (p=0.01, p=0.007) and resumption of miosis between control group than the group 1 and group 3 (p=0.009, p=0.001).The rates of the resumpsion of meiosis in experimental groups were 74.20 (control), 82.71 (group 1), 84.49 (group 2) and 85.49% (group 3), In vitro maturation also increased significantly with (3-mercapthoethanol (group 1=69.49%, group 3=70.22%).The embryo formation on the fourth day in group 1 than the control group, group 2, group 3 (p=0.001, p=0.000,p=0.000) increased more significantly than that in the other groups.Conclusion: The results of this study showed that b-mer-captoethanol (100 mm)has an effect on in vitro maturation and resumption of meiosis of mouse oocytes and improves embryo development.

Purpose: This study sought to determine sex differences in surface anatomical parameters (thickness and surface areas) of human cerebral cortex in different lobes of the left hemisphere in normal right-handed subjects and right-handed subjects suffering from Alzheimer and Parkinson's diseases.Materials and Methods: This cross-sectional descriptive study was performed on 72 normal human brains (38 males, 34 females); 11 brains suffered from Alzheimer (4 males, 7 females), and 13 brains suffered from Parkinson's disease (9 males, 4 females). The age of the males and females in each group was similar.The right hemisphere of each brain was used for neuropathological diagnosis, and the left one was used for morphometrical analysis. The stmation of thickness and surface areas in the cerebral cortex of different lobes of the left hemisphere was performed on photographs of 5mm serial coronal sections of this hemisphere with a linear grid based on unbiased sterelogical method. The results were analyzed by t-student and non-parametrical Mann- Whitney statistical tests.Results: The thickness of the left parietal cortex was significantly smaller in healthy right-handed women than in men (p=0.02). The thickness of cortex in other lobes of the left hemisphere showed no significant sexual difference in healthy right-handed subjects; however, there was a tendency (0.05<p<0.1) for a smaller thickness in women rather than in men. The outer surface area of the left parietal and temporal cortices was similar between two sexes in healthy right-handed subjects, whereas the outer surface area of the left frontal cortex was smaller in women (p=0.02), and there was also a tendency (0.05<p<0.1) for a smaller outer surface area in the left occipital cortex in women. The inner and mean cortical surface areas in different lobes of the left hemisphere were almost similar between two sexes in healthy right-handed subjects. There was a tendency (0.05<p<0.1) for smaller inner and mean surface areas of the left occipital cortex in women. The surface anatomical parameters (thickness and surface areas) of the cortex in different lobes of the left hemisphere were similar between males and females in right-handed subjects suffering from Alzheimer and Parkinson's diseases.Conclusion: It is concluded that the thickness of the left parietal cortex and the outer surface area of the left frontal cortex is smaller in healthy right-handed women than in men. These normal sexual differences in surface anatomical parameters of the cerebral cortex disappear in alzheimer and Parkirison's diseases. Changes in the normal pattern of cortical sexual dimorphism in neurodegenerative diseases can be due to more degeneration of the cerebral cortex in men.

Purpose: Previous investigations have shown that chemical absorbent can produce toxicity which may affect many biological organs. Among these materials, phenol is used in chemical, hygienic and pharmaceutical industries as well as in anatomy laboratories, where it is widely used as an agent of fixation. The aim of this investigation was to evaluate the toxically dose-dependent effects of phenol on the neurobehavioral reactions in the rat.Materials and Methods: In this study, adult rats in the experimental groups (1, 2 and 3) administrated intrapritonneally three different dose of phenol (50, 100 and 200 mg/kg body weight) for 10 days and their magnitute of tremors (slight, moderate and severe) were evaluated by electrophysidogical methods.Results: Our findings showed that 3-5 minutes after the administration of phenol, tremor appeared and continued up to 7-14 minutes. The magnitude and severity of the tremor (slight, moderate and severe) depended up on the dose of phenol administratered.Conclusion: These data indicate that phenol as the same as many chemical compounds, may affect on the activities of the central nervous system and lead to block respiratory and cardiac activities and even cause death in severe cases.

Purpose: We studied of quality and quantity differentation of mouse uterus after the injection of L-Name, L-Arg and normal saline on the 3rd, 4th and 5th days of pregnancy.Materials and Methods: Twenty mice that were 8 weeks old and 200-250g were kept in animal house conditions for one week. By looking at the vaginal plaque, we devided the pregnant mice into 4 groups of 5, consisting of: 1/control group, 2/normal saline group 3/L-Name group and 4) L-Arg group. L-A and L-N were injected according to ip on the 3rd, 4th, and 5th days of pregnancy. On the 18th day of pregnancy, after anesthesia with ether, laparatomy was performed to separate the mothers uteruses. After weighting and fixation with formalin 10%, the prepreations, cutting were done. There were 5 micron cuts, colored with heamatoxillin- Eosin, ready to be studies.Results: The results showed that there was a significant difference between the groups in terms of the mother's, weight, uterus weight, uterus volum and the thickness of endometerium, myometerium and uterus wall (p<0.01). In L-Name group the most increasing, but in L-Arg group the reverse results were seen. Conclusion: Injection of L-Name, L-Arg on the 3rd, 4th and 5th days of pregnancy caused quanlitative and quantitative diffentiation in the uterus of pregnant mice.