OBJECTIVE To study the biocompatibility of skin reproductive membrane. METHODS According to ISO’s standards, the extractions of the skin reproductive membrane were prepared, and the acute systematic toxicity test, primary skin irritant test, cytotoxicity test, gene expression of type I collagen and fibronectin were detected to evaluate the biocompatibility of skin reproductive membrane. RESULTS All of those tests showed negative results. CONCLUSION The skin reproductive membrane has excellent biocompatibility in the level of the systematic, cellular and molecular biology.
【Abstract】 Objective To investigate the effect of retinoic acid (RA) on cell apoptosis and gene regulation of IGF-2in chondrocyte. Methods One 1-month-old Chinese rabbit weighted 500 g was used in this experiment. The chondrocyte from rabbit knee were cultured by enzyme digestion. Twenty-five μL all-trans-retinoic acid (ATRA) (1×10-6 mol/L) were added in the media of cultured chondrocyte for 24 hours as experimental group, while 25 μL DMEM were added as control group. The secretion of collagen Ⅱ was observed by immunohistochemistry method, cell apoptosis was detected by flow cytometry, IGF-2 mRNA and protein expression in chondrocyte were detected by RT-PCR and Western blot analysis. Results The expression of collagen Ⅱ was down-regulated by ATRA in the experimental group. The cell apoptosis in chondrocyte exposed to ATRA at 1 ×10-6 mol/L was 21% ± 2%, which increased 5 times compared with the control group（5% ± 1%）. The IGF-2 mRNA and protein level in the experimental group were decreased 75% and 57%, respectively, compared to the control group. There weresignificant difference between the experimental group and control group in each index (P lt; 0.05). Conclusion RA may down-regulate the secretion and cell prol iferation, but up-regulate the cell apoptosis in chondrocyte. The apoptotic effect may carry out through inhibiting the IGF-2 expression of chondrocyte.
ObjectiveTo observe the effect of preserving tibial residual fibers on the expressions of ligament remodeling related genes in rabbit anterior cruciate ligament (ACL) reconstruction model. MethodsSixty healthy adult New Zealand white rabbits were randomly divided into 4 groups:normal control group (group A, n=6) , sham-operation group (group B, n=18) , non tibial remnant preserved group (group C, n=18) , and tibial remnant preserved group (group D, n=18) . At 2, 6, and 12 weeks after operation, the ligament tissue was harvested to detect the mRNA expressions of collagen type 1A1(COL1A1) , collagen type 3A1(COL3A1) , transforming growth factor β1(TGF-β1), vascular endothelial growth factor (VEGF), growth-associated protein 43(GAP-43) , and neurotrophin 3(NT-3) by real-time fluorescent quantitative PCR. ResultsAt each time point, there was no significant difference in the mRNA expressions of COL1A1, COL3A1, VEGF, and NT-3 between group A and group B (P>0.05) . In group D, the mRNA expressions of COL1A1, COL3A1, TGF-β1, and GAP-43 significantly increased when compared with those of group C at 6 weeks after operation (P＜0.05) ; an increased level of VEGF mRNA was also detected in the group D at 12 weeks after operation (P＜0.05) ; and an increased level of NT-3 mRNA was also observed in group D at 2 and 12 weeks after operation (P＜0.05) . ConclusionThere is a time-dependent manner of angiogenesis-promoting, repair-related, and nerve-related gene expressions after ACL reconstruction with preserving tibial residual fibers during the process of ligamentization. Furthermore, the remnant preservation in ACL reconstruction can promote the expressions of related genes in some time points.
Objective To investigate the development and metastasis of malignant choroidal melanoma cell strain OCM-1-gfp modified with green fluorescent protein(GFP) and the factors which affected the tumor biological behaviors. Methods GFP was transfected into malignant melanoma cell strain OCM-1.Melanoma cells with high and stable expression of GFP were injected into subretinal space and the subcutaneous space of hind leg of Balb/c nude mouse respectively in order to establish orthotopic and heterotopic transplanted tumor models.The development and metastasis process of orthotopic tumor models was observed directly by fluorescence microscope，and the size of the hypodermal tumor was measured by vernier.The expressions of 13 genes in melanoma were detected by means of immunohistochemistry staining. Results Malignant choroidal melanoma cell strain OCM-1 stably expressed GFP and preserved the characteristics of parental generation，OCM-1-gfp may develop melanoma and continue to metastasize in nude mouse.Positive expression of most of the antibodies，including Rb，p53，p21，E2F，NFkappa;B，cyclin D1，proliferation cellular nuclear antigen（PCNA），bcl2、bclXL/S，bax，and epithelial growth factor（EGF）and its receptor（EGFR），was found.While the staining of inhibition gene p16 was negative. Conclusions GFP is the marker for observing the development and metastasis of malignant choroidal melanoma in vivo.The rate of tumor formation and development process in orthotopic models does not differs much from which in heterotopic models of malignant choroidal melanoma.The expressions of lots of genes in malignant choroidal melanoma developed from OCM-1-gfp including p16、p53、NFkappa;B，cyclin D，PCNA，EGF，and EGFR are abnormal. (Chin J Ocul Fundus Dis, 2006, 22: 170-173)
Objective To investigate proliferating cell nuclear antigen (PCNA) gene expression in retinal pigment epithelium (RPE) cells and inhibition of antisense oligonucleotides(AS-OND) encoding PCNA mRNA to gene expression and proliferation of RPE cells, so as to search for new genetic therapy way for pro1iferative vitreoretinopathy (PVR). Methods (1) Rabbit RPE cells cultured in vitro were detected for PCNA expression by streptoavidin-biotin-enzyme complex (SABC) immunohistochemistry at several times. (2) The liposome-mediated synthetic antisense oligodeoxynucleotides (AS-ODN) and sense oligodeoxynucleotides (S-ODN) encoding PCNA were delivered to the RPE cells at different concentrations, then PCNA expresstion were detected by immunohistochemistry. (3) Exposed to different concentrations of AS-ODN and S-ODN, growth activity and suppressive rate of RPE cells were measured by methyl thiazolyl tetrazolium (MTT) methods. Results (1) PCNA were expressed in RPE cells, culmination in 48 hours of culture. (2) PCNA expression were markedly suppressed in the RPE cells treated with 0.28 and 1.12 μmol/L PCNA AS-ODN. (3) 0.28 μmol/L and 1.12 μmol/L PCNA AS-ODN significantly inhibited proliferative activity of RPE cells in a dose-dependent manner, the arrest rates of cellular growth reached 53% and 81% respectively. Conclusion AS-ODN complementary to PCNA mRNA at some concentration can sequence-specifically suppress PCNA expression in RPE cells and cellular proliferative activity, and show potential application to further experimental study for PVR genetic medication. (Chin J Ocul Fundus Dis, 2002, 18: 231-233)
Ion channels are involved in the mechanism of anesthetic action and side effect. The transcription and expression of ion channel genes can be modulated by general anesthetics. The adverse effect of continuous infusion of etomidate has been concerned. However, the effects of etomidate on mRNA expressions of ion channel genes remain unclear. In this study, we exposed Daphnia pulex in 250 μmol/L of etomidate for 240 min and observed the change of heart rate, phototactic behavior and blood glucose during the period of exposure, as well as the mRNA expressions of 120 ion channel genes at the end of the experiment. Compared to the controls, heart rate, phototactic behavior and blood glucose were not influenced by 250 μmol/L of etomidate. According to the quantitative PCR results, 18 of 120 Daphnia pulex ion channel genes transcripts were affected by persistent 240 min exposure to 250 μmol/L of etomidate: 2 genes were upregulated and 16 genes were down-regulated, suggesting that etomidate showed effects on many different ion channels in transcription level. Systematical exploration of transcriptional changes of ion channels could contribute to understanding of the pharmacological mechanism of etomidate.
Objective To study the differentiation of the human osteoblasts during the construction of the tissue engineered periosteum with the human acellular amniotic membrane(HAAM).Methods To construct the tissue engineered periosteum (n=60) with HAAM, the human fetal osteoblasts were used. The fetal osteoblasts were cultured for 2, 4, 6, 8, and10 days, and then their total RNA was extracted, which were reversely transcripted to cDNA. The realtime PCR analysis was used to reveal Cbfal and Osterix, and the cycle threshold (Ct) was also measured. The simplycultured osteoblasts were used as the control group (n=20).Results The expression of Cbfa1 was higher in the experimental group on the 2nd day when compared with that on the 4th, 6th, and 8th day(P＜0.05). The same result existed on the 10th day when compared with that on the 4th and 8th day. The expression of Osterix increased and was highest on the 8th day when compared with the other results(P＜0.05). Both of the 2 gene expressions were decreased in the control group when compared with those in the experimental group, but with no significant difference(P＞0.05). Conclusion Cbfa1 and Osterix can be normally expressed by the osteoblasts after their integration with HAAM. As a scaffold, HAAM can be used to keep the osteoblast phenotype and differentiation with an osteoconductive ability. Such a cell-scaffold complex may provide a basis for the osteogenesis.
RNA can be labeled by more than 170 chemical modifications after transcription, and these chemical modifications are collectively referred to as RNA modifications. It opened a new chapter of epigenetic research and became a major research hotspot in recent years. RNA modification regulates the expression of genes from the transcriptome level by regulating the fate of RNA, thus participating in many biological processes and disease occurrence and development. With the deepening of research, the diversity and complexity of RNA modification, as well as its physiological significance and potential as a therapeutic target, can not be ignored.