ABSTRACT
@#BACKGROUND. In the present situation, other than establishing the cause of death, one other major problem that the world is still facing in the forensic medical science is determining the time of death. To meet this requirement, scientists have been studying the organ system at cellular level based on medical and other sciences. Determining the time of death solves the problem which judicial organization has to face and it is significant to demonstrate citizen’s religion and traditional rituals. Now there are two methods, early and late reflection in the corpse. When we determine the time of death, we have purposed changes of epithelial cell structures and movements in the smear from the cornea after death. The studies related with those have not yet being undertaken in our country. Therefore, we want to investigate what changes are related with corneal cytology depend on the time of death. PURPOSE: To study the changes of epithelial cell structure and movement in the smear from the cornea after death. CONCLUSION: We observed the marked changes in the cell structure, including increased nucleus/cytoplasmic ratio and also a nuclear karyolysis of the epithelial cells of the cornea at 1-2 hours, 3-4 hours, 5-7 hours, 8-11 hours, 12-17 hours, 1 day and 2 days after the death, respectively. From the research results, by observing the number of epithelial cell of the cornea, we can see that when the time of death is prolonged, the number of epithelial cell increases. When we compared the time of death with the determined number of epithelial cells, there are statistically significant (ρ=0.981, p<0.001).
ABSTRACT
AIM:To investigate the effects of amnion epithelial cell ( AEC) suspension liquid on the biological behavior of the rabbit's corneal epithelium, combined with the in vitro and in vivo experiments. · METHODS: The rabbit's corneal epithelium were cultured in the lower chamber of transwell, and AEC suspension liquid was dropwised in the upper chamber. There was only culture medium in the upper chamber of the control group. The proliferation of rabbit's corneal epithelium was observed with CCK-8 automated colorimetry and the expression of PCNA was detected by immunocytochemistry. We used the scratch wound assay to detect the migration of corneal epithelial cell ( CEC ) . The in vivo models were established by placing a 10mm diameter corneal trephine in the center of the cornea, within 1mol/L NaOH for 1min. We divided those into three groups: treatment group of AEC suspension liquid eye drop, AEC suspension liquid subconjunctival injection and the control group without any treatment. Using the slit- lamp biomicroscope and fluorescence staining to observe the cornea per week. After 28d we took the eyeballs with the HE staining. The expression of VEGF was detected by immunohistochemistry. ·RESULTS: The activity of CEC with AEC treatment was much higher than the control group ( P< 0. 05 ). The expression of PCNA increased in AEC group (P<0. 05). And the migration of CEC in the AEC group was faster than the control one. In vivo, the inflammation of the corneal and the CNV of the AEC group were all significantly reduced compared with the control group (P<0. 05 ). There were less invasive cells and more ordered organization arrangement in ACE group observed by the HE staining. The expression of VEGF and mcp-1 in these two AEC treatment groups all significantly decreased compared with the control group (P<0. 05). ·CONCLUSION: AEC suspension liquid can promote the proliferation and migration of the rabbit's corneal epithelium. The potential of AEC suspension liquid as a therapy for acute corneal alkali burn.
ABSTRACT
PURPOSE: To identify the effects of microenvironmental changes caused by human corneal epithelial damages to characteristics or differentiation of human mesenchymal stem cells (hMSCs). METHODS: Artificial corneal damage was induced onto a cultured monolayer of human corneal epithelial cells. hMSCs were then co-cultured with damaged human corneal epithelial cells (dIHCE). Morphological changes in the co-cultured hMSCs were observed. To elucidate the differentiation of hMSCs into corneal keratocytes or epithelial cells, the expressions of alpha-smooth muscle actin, keratin-3/-12, and E-cadherin were confirmed by immunofluorescence. RESULTS: hMSCs co-cultured with dIHCE showed enhanced adherence in the neighborhood of dIHCE and morphological change into dendritic shapes at 6 days post-seeding. Although the expression of alpha-smooth muscle actin, known as hMSCs marker, significantly decreased at the dIHCE-contacted site of hMSCs; there were no expressional changes on keratin-3/-12 and E-cadherin, the markers of corneal epithelial cells. Interestingly, positive expression of corneal epithelial marker keratin-3/-12 was observed in dIHCE co-cultured hMSCs. hMSCs co-cultured with normal human corneal epithelial cells (nIHCE) were unable to attach, and showed no change in the expression of alpha-smooth muscle actin. CONCLUSIONS: It is proposed that dIHCE causes a morphological change in hMSCs, and decreased expression of alpha-smooth muscle actin. These results suggest that dIHCE can affect a change in the characteristics and differentiation of hMSCs.