Objective To review research progress of corneal tissueengineering.Methods The recent articles on corneal tissue engineering focus on source and selection of corneal cells, the effects of growth factors on culture of corneal cells in vitro. The preparation and selection of three-dimensional biomaterial scaffolds and their b and weak points were discussed. Results The corneal tissue engineering cells come from normal human corneal cells. The embryo corneal cell was excellent. Several kinds of growth factors play important roles in culture, growth and proliferation of corneal cell, and incroporated into matrix.Growth factors including basic fibroblast growth factor, keratinocyte growth factor, transforming growth factor β1 and epidermal growth factor was favor to corneal cell. Collagen, chitosan and glycosaninoglycans were chosen as biomaterial scaffolds. Conclusion Human tissue engineering cornea can be reconstructed and transplanted. It has good tissue compatibility and can be used as human corneal equivalents.
目的:探讨胚胎发育不良性神经上皮肿瘤(DNT)的临床、影像及病理学特征、诊断及鉴别诊断.方法:回顾性分析8例胚胎发育不良性神经上皮肿瘤患者的临床和影像学资料,进行光镜和免疫组织化学染色观察,并获得6例的随访资料.结果:胚胎发育不良性神经上皮肿瘤男性7例,女性1例,年龄为5～19岁,平均年龄13岁,5例以癫痫小发作为主要临床表现,病变均位于幕上,以皮层为主,影像学检查均无明显的占位效应及瘤周水肿。肿瘤细胞主要由少突胶质样细胞(OLC)、神经元和星形细胞组成,4例伴有皮质发育不良。免疫组织化学结果为神经元及部分少突胶质样细胞呈嗜铬素A、突触素及S-100阳性表达;少突胶质样细胞呈胶质纤维酸性蛋白(GFAP)阴性表达,而星形细胞呈GFAP阳性表达;Ki-67抗原标记指数lt;1%。结论: 胚胎发育不良性神经上皮肿瘤为WHOⅠ级良性肿瘤,可结合临床、影像及病理学表现明确诊断,预后良好,无需放疗和化疗。
Objective To investigate the effects of platelet-derived growth factor(PDGF) on the expression of α-smooth muscle actin(α-SMA) of cultured human retinal pigment epithelium cells(RPE). Methods Cultured human RPE cells of the 4-6 th passages were divided into two groups: Delbecco′s modified Eagle′s medium (DMEM) and 2%DMEM (20 g/L foeta calf serum+DMEM). PDGF (0,1,50 ng/ml) was added to medium.The expression of α-SMA was detected and quantitatively analyzed by image process of immunofluorescence.Results PDGF stimulated the expression of α-SMA of human RPE cells.In group of DMEM, The rate of RPE of α-SMA expression was 40%-50% and the intension of fluorescence was 8.08 without PDGF. After stimulated by PDGF(1 ng/ml,50 ng/ml), the rates were 80% and 90% respectively, and the intension of fluorescence were 12.35 and 17.23. In 2%DMEM group, The rates of RPE of α-SMA expression were 85% without PDGF, and 95% ,100% respectively treated with PDGF (1 ng/ml,50 ng/ml). The intension of fluorescence was 14.79 without PDGF, and after stimulated by PDGF, they were 16.28 at 1 ng/ml and 21.36 at 50 ng/ml，which was 2 .7 times ber than that in DMEM group without PDGF. Conclusion PDGF could stimulate RPE cells to express α-SMA. (Chin J Ocul Fundus Dis，2003，19：201-268)
Objective To study the expressions of Wnt5a, MMP2, and MMP14 in the primary lesions of gastric cancer and the influences on clinicopathologic features. Methods The expressions of Wnt5a, MMP2, and MMP14 in the specimens of 106 patients with gastric cancer and 39 patients from the adjacent normal gastric tissues were detected by immunohistochemical staining, χ2 test and non-parametric test were used to analyze the relationships among them and between them and their influences on the clinicopathologic features. Results Extensive expressions of Wnt5a, MMP2, and MMP14 were demonstrated in the gastric cancer, which were significantly higher than those in the normal gastric tissues respectively (Plt;0.05). Positive expression of Wnt5a was associated with larger tumor diameter, deeper depth of invasion, higher degree of regional lymph node metastasis, later TNM stage, and higher rate of lymph node metastasis (Plt;0.05). In addition, Wnt5a expression was also associated with lymphatic infiltration and vascular infiltration (Plt;0.05). The expressions of MMP2 and MMP14 were associated with lymphatic infiltration, but not with vascular infiltration. Higher expressions of MMP2 and MMP14 were correlated with deeper tumor invasion, higher degree of regional lymph node metastasis, later TNM stage, and higher rate of lymph node metastasis (Plt;0.05). In addition, higher expression of MMP2 possesed greater tumor diameter (Plt;0.05). Spearman rank correlation analysis revealed the positive relation between Wnt5a and MMP2 （rs=0.240, P=0.014）, Wnt5a and MMP14 （rs=0.251, P=0.010）, as well as MMP2 and MMP14 （rs=0.444, P=0.000）. Conclusion Higher expressions of Wnt5a, MMP2, and MMP14 seem to promote invasion and metastasis of gastric cancer, and there are positive relations among their expressions.
Objective To observe the effect of exogenous basic fibrob last growth factor (bFGF) on apoptosis of cultured human retinal pigment epithelial (RPE) cells exposed to visible light,and determine the role of bFGF, fibroblast growth factor receptor 1 (FGFR1),bcl-2 and caspase-3. Methods 2000±500) lx cold white light was used. Exogenous bFGF was utilized during culture. Annexin annexin V-fluoresce in isothiocyanate/propidium iodium (V-FITC/PI) labeling,flow cytometry, Immunocytochemical staining, enzyme associated absorb examing and reverse transcriptional polymerase chain reaction (RT-PCR) were used to determine the apoptosis, the expression levels of bFGF, FGFR1, bcl-2, as well as the activity of caspase-3. Results No protective effect of bFGF was observed under the concentration 5 ng/ml.A significant inhibition of apoptosis was found in 10 ng/ml and 20 ng/ml groups （P＜0.05）. The upregulation of bcl-2 was observed in bFGF (10 ng/ml, 20 ng/ml) protreated groups（P＜0.01）.Compared to no light exposure group,all light exposure groups (including bFGF pro-treated) had higher endogenous bFGF and FGFR1 levels （P ＜0.05）, and the increase was concentration dependent.The bFGF and FGFR1 levels were higher in exogenous bFGF applied (gt;5 ng/ml) groups than light exposure groups（P＜0.05）. The caspase-3 activity was significantly inhibited in bFGF (10 ng/ml) pro-treated groups. Conclusions Human RPE cells exposed to visible light were rescued by application of exogenous bFGF in vitro.The probable protective mechanism of bFGF partly is directly binding to FGFR1 or potentiating endogenous bFGF autocrine loop,to upregulate bcl-2 and to inhibit caspase-3 activation. (Chin J Ocul Fundus Dis，2003，19：24-28)
Objective To explore the expression and activation of transcription factor E2F1 in cultured human retinal pigment epithelium (RPE) cells. Methods Cultured human RPE cells were divided into two groups after synchronization: one was cultured in Dulbecco′s modified Eagle′s medium (DMEM) without serum; the other was cultured in DMEM supplemented with 20% serum of newborn calf. The expressions of E2F1 protein in two groups were detected by Western blot analysis. The E2F1-DNA binding activities were measured by gel mobility-shift assay(EMSA). Results E2F1 protein of 60 000 molecular weight was detected in the nuclear extract of human RPE cells, and serum stimulation could increase its expression（P＜0.001）. EMSA exhibited the increased binding activity of E2F1 in the serum-stimulated RPE cells with DNA. Conclusions E2F1 is expressed in the nuclei of human RPE cells. Serum stimulation can increase its protein expression as well as binding activity, so as to play a regulation role of gene transcription. (Chin J Ocul Fundus Dis, 2002, 18: 224-226)
Objective To establish a method for primary culture of iris pigment epithelial cells(IPE). MethodsEnzyme-Assisted microdissection was used to isolate and cultivate the IPE cells.An identification was made with microscopic and immunohistochemical observations.Results IPE were successfully sultured and showed on differences with RPE in primary culture and subculture.ConclusionEnzyme-Assisted microdissection is a reliable and quick method for the isolation of IPE.
Endogenous pigment epithelium derived factor (PEDF) shows great potential as a drug target for the treatment of diabetes retinopathy (DR) due to its anti-angiogenesis, anti-inflammatory, neuroprotective and neurotrophic effects. PEDF plays a biological role by combining with receptor proteins on cell membrane surface and regulating a variety of signaling pathways. Low density lipoprotein receptor related protein 6 plays a role in inhibiting oxidative stress reaction, inflammatory reaction, and neovascularization of DR. Adipose triglyceride lipase, laminin receptor, plexin domain containing 1 (PLXDC) 1, PLXDC2 and F1-adenosine triphosphate synthase have the effect of promoting endothelial cell apoptosis, among which PLXDC1 also has neuroprotective effect. By clarifying the receptor that PEDF acts on, exploring the affinity between the receptor and PEDF, the difference in the expression level of each receptor in the process of disease, and the specific function that PEDF plays after binding with specific receptors, we can develop fusion protein drugs for the active domain of high affinity of receptors, have a clearer understanding of the pathogenesis of DR, and take PEDF or PEDF receptor as the target to consolidate the theoretical basis for the development of new therapeutic drugs and strategies for DR.