Abstract: Objective To investigate the influence of cryopreservation on cellular viability of latepregnancy fetal valved allografts in human. Methods The fetal valved allografts with gestational ages ranged from 24 to 40 weeks were sterilely procured within 6 hours after brain death. Each sample was bisected into control group and experiment group. The cellular viability of control group was directly tested and that of experiment group was examined after being storaged in liquid nitrogen for a week through a programmed frozen procedure. The light microscopy, tissue culture and Methylthiazol tetrazolium assay (MTT assay) were used to determine the cellular viability. Results Twelve latepregnancy fetal valved aortic allografts were procured. Light microscopy showed the integrity of the basic structure of the thawed aorta, the normal structure of the collagen and elastic fibers, with part of vascular endothelium lost. There were lots of cells deriving from both groups,but the cellular growing rate of the experiment group was relatively slower. At 490 nm, MTT assay valve of control group was 0.442±0.046, and that of experiment group was 0.424±0.041. The difference between two groups failed to statistically significance(t=1.617, P=0.328). Conclusion There were viable cells in latepregnancy fetal valved allografts after cryopreservation.
Objective To investigate effects of neural retina on development of the structure of outer blood retinal barrier in embryogenesis. Methods The retinal neural epithelium (RNE) and pigment epithelium (RPE) layers of 150, 120 and 90 embryonic chicken eyes incubated for 7,10, and 14 days were peeled off. RNE was used to prepare the culture medium with different conditions (7drcSF3, 10drcSF3, 14drcSF3). RPE cells of 7- and 14-incubated chicken embryos were cultured on laminin-coated transwell filter. The SF3, 7drcSF3, 10drcSF3 , 14drcSF3 medium were used respectively in the apical chamber and SF2 was used in basolateral chamber. After the formation of monolayer, the transepithelial electrical resistance of the RPE was detected. After the fixation of RPE cells, the condition of the tight junction among the cells was observed by immunohis tochemistry and transmission electron microscopy. Results For the RPE cells of 7-and 14-day incubated embryonic eyes, the difference of TER in various medium of SF3/SF2, 7drcSF3/SF2, 10drcSF3/SF2, 14drcSF3/SF2 was statistically significant (P＜0.01). The polarity of RPE cells was induced and the netlike tight junctional strands was urged in the retina-conditioned medium. Conclusion The neural retina may actively promote the formation of the structure of outer blood retinal barrier. (Chin J Ocul Fundus Dis，2004，20：237-240)
Abstract In order to repair the bone defect afteroperation of benign lesion of extremity, the fetal demineralized bone was applied in 10 cases. These cases were followed up for 6 months to 8 years. The results showed that the grafted bone was integrated with the host bone in 6 months. Noadverse effect was found. The demineralized bone did not induce rejection. The advantages of using fetal demineralized bone were as follows: easily obtainable,its preparation and method of storage simple, and low finacial cast.
Objective To investigate the feasibility of fetal liver cells for liver tissue engineering, the supporting function of poly L lactic acid (PLLA) scaffold for fetal liver cells and the effects of oncostatin M (OSM), nicotinamide (NA) and dimethyl sulfoxide(DMSO) on growth and hepatic differentiation. Methods After three dimensional PLLA scaffolds having a porous structure were prepared by using NH 4HCO 3 particle, fetal liver cells obtained from E14.5 C57BL/6CrSlc murine embryos were inoculated in the scaffolds. Cells were cultured in Williams’E medium with or without OSM, NA and DMSO for 30 days. Changes in cell number, liver-specific function, and cellular morphology were observed. Results When compared with in monolayer culture, cell number and albumin secretion increased obviously in three-dimensional PLLA. Alburmin secretion increased slightly in OSM group of monolayer culture, but increased obviously in OSM groupo of PLLA culture and in OSM/NA/DMSO group of both monlayer and PLLA cultures. Conclusion The three-dimensional PLLA scaffold is a good supporting material for the cultivation of tetal liver cells. OSM, NA and DMSO remarkaly stimulated maturation of hepatic parenchymal cells in vitro in terms of morphology and liver-specific function.
Objective To observe the effect of BMSCs transplantation on gene and protein expression of VEGF receptor fetal l iver kinase 1 (Flk-1) after spinal cord injury (SCI), and to investigate the mechanism of repairing the SCI by BMSCs transplantation. Methods BMSCs were isolated and cultured from five 4-week-old male Wistar rats weighing100-120 g. The SCI model was made by using the modified Allen’s impactor device. Eighty-one adult female Wistar rats weighing 220-250 g were randomly divided into 3 groups: sham-operated group (group A, n=21), in which spinous process and vertebral plate of thorax 8-10 spinal cord segment were removed; DMEM group (group B, n=30), in which rats received four injections of DMEM in the peri-lesion area; and BMSCs group (group C, n=30), in which rats received four injections of BMSCs in the peri-lesion area. The changes of Flk-1 mRNA expression in rats’ spinal cord tissues were detected with RT-PCR method 1, 3 and 5 days after transplantation. The expression of Flk-1 protein was observed by using immunohistochemical technology in spinal cord 3, 7 and 14 days after transplantation. Results Morphology of the primary cultured BMSCs was various. Cell morphology tended to be uniform with the accumulation of passages, which appeared flat and spindle-shaped. RT-PCR results showed that there was no significant differences (P gt; 0.05) in Flk-1 mRNA expression between group C and group B at different time points after transplantation. But Flk-1 mRNA levels of group B and group C significantly increased and peaked 1 day after transplantation (P lt; 0.01), and then decreased 3 days after transplantation (P lt; 0.01) compared with that of group A, and were still higher than that of group A 5 days after transplantation (P lt; 0.05). Immunohistochemical staining results revealed that the expression of Flk-1 in group B was enhanced 3 and 7 days after transplantation compared with group A, which was significantly different (P lt; 0.01). There was no significant difference in the expression of Flk-1 between group B and groupp A 14 days after transplantation (P gt; 0.05). There was no significant difference in Flk-1 protein expression between group C and group B 3 days after transplantation (P gt; 0.05). The expression of Flk-1 protein in group C was significantly higher than that in group B 7 and14 days after transplantation (P lt; 0.01). Conclusion BMSCs transplantation after SCI does not have regulatary effect onthe expression of Flk-1 mRNA, but it does upregulate the Flk-1 protein expression, which may be one of the mechanisms of repairing SCI.
OBJECTIVE: To select a satisfactory surgical approach in vaginoplasty with minimum injury and maximum effectiveness. METHODS: From January 1997 to December 1998, 86 cases of congenital absence of vagina were treated by three types of vaginoplasty, using abdominal skin graft, fetal skin graft and vulvar-inguinal skin flap respectively. The duration of operation and hospitalization, the wound healing of donor site, as well as the moist sensation of the artificial vagina and the sexual life quality were compared among the three types of vaginoplasty. RESULTS: Compared with those by abdominal skin graft and vulvar-inguinal skin flaps, the vaginoplasty by fetal skin graft had the shortest surgical duration (P lt; 0.01); the duration of hospitalization with fetal skin grafting was shorter than that of abdominal skin grafting (P lt; 0.01) but almost the same as that of vulvar-inguinal skin transferring (P gt; 0.05). The fetal skin grafting had minimum injury. Moreover, artificial vagina by fetal skin grafting had the best moist sensation and the most satisfactory sexual life quality (P lt; 0.01). CONCLUSION: In view of the minimum injury and maximum mimic of nature vagina, the vaginoplasty by fetal skin graft is the most ideal approach among the three types of vaginoplasty investigated in this trial.
ObjectiveThis study aims to compare different references for the fetal risk of drugs used in pregnancy to provide evidence for the safety of drug use in pregnancy.MethodsFour drug databases, including Lexicomp, Micromedex, TERIS, and Reprotox, as well as two books of drugs in pregnancy edited by Briggs and Schaefer, were searched. Descriptive analysis was performed regarding the definition of pregnancy recommendations and the specific content of medication.ResultsThe six references employed slightly different approaches to drugs in pregnancy, however, all of them included summaries of the risk in pregnancy, data of crossing the placenta, and human and animal data. The databases of Micromedex, TERIS, and a book edited by Briggs had their risk classification systems for drug use during pregnancy. For specific drugs, the summary of different information in pregnancy was different, the amount and content of listed evidence varied, and there was no evaluation of the quality and relevance of evidence among the references.ConclusionsThere is no consensus on the risk assessment of drugs in pregnancy. Risk classification systems for drugs in pregnancy are still an important method for determining the fetal risk of drugs. The existing references merely list studies of drugs in pregnancy, without comprehensive quality assessment. A methodological study of assessment of the risk of drugs in pregnancy is required.
OBJECTIVE: To investigate the repairing effect of transplantation of allogeneic fetal bone in combination with a covering cryopreserved periosteal allograft to bone defect. METHODS: Twenty Long-eared white male rabbits were chosen as experimental model of bilateral 12 mm combined bony and periosteal radial defect. Cryopreserved allograft periosteum with allogeneic fetal bone were implanted in the left defect as experimental side and fetal bone was simply transplanted in the right defect as control side. Bone repair process in the two groups were compared by macroscopy, microscopy, roentgenograms and the contents of calcium and phosphate in the defect area at 2, 4, 8 and 12 weeks after transplantation. RESULTS: There was significant statistic difference in the contents of calcium and phosphate between the experimental and control sides at 4, 8 and 12 weeks after transplantation (P lt; 0.05). With time passing by, the contents of calcium and phosphate have the increasing trends. In the experimental group, lamella bone was seen and medullary canal recanalized at 8 weeks postoperatively. The histological section showed the bone lacuna and lamella bone were formed. CONCLUSION: It suggests that allogeneic fetal bone in combination with a covering cryopreserved periosteal allograft can promote bone repair, and allogeneic fetal bone is excellent bone substitute.
Objective To investigate the possibility of culturing human oral keratinocyte using autologous serum in order to provide theoretical and technical foundation for clinical application of tissue engineering oral mucosa epithelium.Methods The human oral keratinocytes were cultured by the medium containing different concentrations of autologous serum(10%,20%,30%)and fetalbovine serum (10%), respectively. The growth conditions for the cell and the mucosa epithelium in the groups were observed, the cell growth curves were drawn, and the population doubling time (PDT) was counted. Results The results showed that the human oral keratinocyte could proliferate well in the medium containing autologous serum or fetal bovine serum. The differences in the 24hour clone rate and PDT were not significant. Both the area and the thickness of the cultured oral epithelium increased with the increase of the autologous serum concentration, and the difference between autologous serum and fetal bovine serum was significant, especially with the medium containing 20% autologous serum( P＜0.05) . The human nature of the cultured epithelium was demonstrated by the immunofluorescent mouse anti-HLA antigen. Conclusion The autologous serum can replace the fetal bovine serum to culture the oral keratinocyte well, and the cultured oral mucosa epithelium can be better differentiated in the autologous serum than in the fetal bovine serum.
Objective Neuron purification is essential to procedure of various nerve cell experimental research, however, at present there is few reports on the effect of various factors on neural axons during purification. To find out a simple method of neuron purification, and to investigate the influence factors of corresponding purification culture in dorsal root gangl ion (DRG) tissue culture on β3-tubul in positive axon. Methods The DRGs were obtained from the 3 days neonatal SD rat microscopically and were made into cell suspension. Then, the amount of attached DRG neurons and non neuronal cells in poly-D-lysine (PDL) group, PDL/Laminin (PDL/LN) group and collagen-I (Col I) group was observed from 10 to 100 minutes. Then, the extension and arborization of β3-tubul in positive axons were observed after 72 hours completely randomised DRG tissue culture for the research of the influences among culture substrates (PDL, PDL/LN, and Col I), FBS (0, 5%, and 10%), 5 fluorouracil (5-Fu, 0, 20, and 40 μmol/L), and cytrarabine (Ara-C, 0, 10, and 20 μmol/L). Results Adherent cells were observed instantly after inoculation by inverted phase contrast microscope and inverted fluoresence microscope; after cell suspension was removed, adherent growth of DRGn cells and non-DRGn cells were still seen. In PDL group, the amount of NSE negative cells was significantly higher than that of NSE positive cells at 10 and 30 minutes (P lt; 0.05); the amount of NSE positive cells was significantly higher than that of NSE negative cells at 80, 90 and 100 minutes (P lt; 0.05). In PDL/LN gruop, there was no significant difference (P gt; 0.05) in the amount of NSE negative cells and NSE positive cells at 10, 20, 30, 40, and 50 minutes; the amount of NSE positive cells was significantly higher (P lt; 0.05) than that of NSE negative cells at 60, 70, 80, 90, 100 minutes. In Col I group, the amount of NSE negative cells was higher than that of NSE positive cells at 10-40 minutes, but showing no significant difference (P gt; 0.05); the amount of NSE positive cells was significantly higher (P lt; 0.05) than that of NSE negative cells at 70-100 minutes. At 72 hours after DRG tissue culture, the best result of β3-tubul in positive axon extension and arborization was obtained when the substrate level was PDL/LN, and the average length of PDL/LN level was significantly larger than that of other two substrates (P lt; 0.05). The highest number of β3-tubul in positive axon distal end was obtained at 5% concentration level of FBS (P lt; 0.05), but showing no significant differences in β3-tubul in positive axon length among three levels (P gt; 0.05). Both the most of β3-tubul in positive axon distal ends and the longest β3-tubul in positive axon average length were obtained at 0 μmol/L concentration level of 5-Fu, showing significant differences between 0 μmol/L level and 20, 40 μmol/L levels (P lt; 0.05). A similar result of β3-tubul in positive axon distal end was got at the 0 μmol/L level and 10 μmol/L level of Ara-C, which was significantly higher than that of 20 μmol/L level (Plt; 0.05). Conclusion? A purified DRG neuron suspension for neuron culture could be obtained via PDL differential attachment for 30 minutes. When DRG neuron culture, neuron special medium, PDL/LN substrate and 10 μmol/L Ara-C are recommended in β3-tubul in positive axon research.