Epigenetic modifications such as DNA methylation, histone post-translational modifications, non-coding RNA are reversible, heritable alterations which are induced by environmental stimuli. Major risk factors of diabetes and diabetic complications including hyperglycemia, oxidative stress and advanced glycation end products, can lead to abnormal epigenetic modifications in retinal vascular endothelial cells and retinal pigment epithelium cells. Epigenetic mechanisms are involved in the pathogenesis of macular edema and neovascularization of diabetic retinopathy (DR), as well as diabetic metabolic memory. The heritable nature of epigenetic marks also playsakey role in familial diabetes mellitus. Further elucidation of epigenetic mechanisms in DR can open the way for the discovery of novel therapeutic targets to prevent DR progression.
In thiis study,we show thai carbachol stimulates the accumulation of inositol phosphates(InsPs)in human rellnal pigment epithelium (RPE)cells and atropine blocks the carbachol-induced effect ,suggesting the existence of musearinie acelyleholine receptors in human RPE cells. In contrast,noradrenaline,serotonin, cpidermal growth factor (EGF),isoproterenol,and
NECA (5'-[N-ethyl]-carboxamido-adenosine)do not influence the basal levels of InsPs.Moreover,isoprmerenol and NECA do not affect the carhaehol elevated levels of InsPs.EGF,howcvcr,does potentiate the carhaehol stimulated elevation of InsPs in a dose-dependent manner ,suggesting an interaction between EGF and musearinie receptors in cultured human RPE cells.
（Chin J Ocul Fundus Dis,1994,10:220-222）
OBJECTIVE: To isolate and characterize mesenchymal stem cells (MSCs) derived from bone marrow of Banna minipig inbred line (BMI). METHODS: BMI-MSCs was isolated from bone marrow by density gradient centrifugation and cultured in DMEM (containing 15% bovine serum) at 37 degrees C with humidified 5% CO2. These cultured stem cells were characterized in clonal growth, expression of specific markers and capability of differentiation. RESULTS: Mesenchymal stem cells were proliferative and could be expanded rapidly in vitro. Clonal growth of these cells can be observed when small amount of cells was inoculated. These cells were SH2, SH3, SH4, SB10 and SB21 positive. And it was proved that these cells possess osteo-differentiation ability, up-regulated alkaline phosphatase expression and calcium secretion after osteosupplement was added into the media for several days. CONCLUSION: Mesenchymal stem cells derived from bone marrow of BMI possess the general characters of stem cell.
ObjectiveTo observe the effect of subretinal injection of retinal pigment epithelium (RPE) cells for RPE in mice.
MethodsA total of 30 postnatal day 7 C57BL/6J mice were randomly divided into normal mice group, OIR model group and OIR model cell transplanted group, 10 mice in each group. The OIR model was induced in mice of OIR model group and OIR model cell transplanted group. The RPE cells were subretinal injected into the RPE of mice in OIR model cell transplanted group. At 20 days after the injection, the RPE thickness was evaluated by fluorescence microscope. The expression of RPE65, Bestrophin and zonula occludens-1 (ZO-1) were estimated by Western blot and real-time quantitative PCR (RT-PCR).
ResultsThe thickness of RPE in OIR model mice was thinner than that in normal mice; the thickness of RPE in OIR model cell transplantation mice was significantly thicker than that in the OIR model mice. The results of Western blot and RT-PCR indicated that the differences of protein (F=8.597, 18.864, 25.691) and mRNA expression (F=39.458, 11.461, 34.796) of RPE65, Bestrophin, ZO-1 were statistically significant between OIR model group and OIR model cell transplanted group (P < 0.05).
ConclusionsSubretinal injection of RPE cells can promote RPE thickening. RPE65 and Bestrophin protein relative expression levels increased, ZO-1 protein relative expression levels reduced; mRNA expression levels of RPE65, Bestrophin and ZO-1 genes increased.
Objective To study the inhibitive effect of adenovirus mediated CD gene and 5-FC on proliferative human retinal pigment epithelial (HRPE) cells, and to search for an effective method to take precautions against proliferative vitroretinopathy (PVR).Method Different concentrations of CD and 5-FC were added respectively to the cultured third-growth-generation HRPE cells.Transferance rate was detected by positive HRPE cells marked by X-gal and LacZ. The number of HRPE cells were counted and evaluated by methylthiazol-tetrazollium (MTT) method. Results The adenovirus mediated CD gene could be transfered into HRPE cells with a dose-dependent manner. Positive HRPE cells with CD gene could transform 5-FC to 5-Fu,which could inhibit the increase of HRPE cells effectively. No obvious bystander effect on the growth of HRPE cells was detected.Conclusions The adenovirus may introduce a foreign gene into cultured HRPE cells efficiently. It could be a good method to treat and prevent PVR by medication. (Chin J Ocul Fundus Dis，2003，19：168-171)
OBJECTIVE: To provide an ideal method for repairing the circular cicatricial contracture of thigh. METHODS: Deep inferior epigastric perforator (DIEP) island flaps was elevated based only on the deep inferior epigastric artery and vein and transferred to cover the thigh wound after scar had been resected. RESULTS: Four DIEP island flaps was applied clinically and all flaps survived. The size of the flaps ranged from (8 cm x 28 cm) to (11 cm x 32 cm). Venous return and edema had been obviously improved postoperatively. There was no abdominal weakness and hernia in the donor sites. CONCLUSION: DIEP flap not only retains the advantages of TRAM flap such as good blood supply and rich tissue volume, but also preserves the integrity of the rectus abdominis muscle. DIEP island flap is a good material for repair of the circular cicatricial contracture of the thigh.
ObjectiveTo observe the expression of hot shock protein 47 (HSP47) in pre-retinal membrane of proliferative vitreoretinopathy (PVR) and the influence of transforming growth factor-β2 (TGF-β2) on the expression of HSP47 in retinal pigment epithelial (RPE) cell.
MethodsPre-retinal membranes were collected and observed by hematoxylin-eosin, Masson and immunohistochemical staining. Cultured ARPE-19 cells were treated with TGF-β2 at serial concentration (0, 1, 5, 10 ng/ml) and time (0, 12, 24, 48 hours), respectively. And then the mRNA and protein expressions of HSP47 and Col-Ⅰ were measured by fluorescence quantitative reverse transcription polymerase chain reaction and Western blot at the same time.
ResultsA lot of epithelial cells with pigmental particles were observed in pre-retinal membranes of PVR, much accumulated collagen protein was observed in the specimens, and HSP47 positive expression was bserved in cytoplasm and stroma of most of the epithelioid cells. Compared with 0 ng/ml group, the expressions of HSP47 mRNA in ARPE-19 were up-regulated by 1.32, 2.35, 1.85 fold, significant differences were observed in all groups (F=27.21, P<0.05); the expressions of protein were up-regulated by 2.33, 2.89, 2.60 fold, significant differences were observed in all groups (F=39.78, P<0.05). The expressions of Col-Ⅰ mRNA were up-regulated by 1.29, 1.52, 2.11 fold, significant differences were observed in all groups (F=23.45, P<0.05); the expressions of protein were up-regulated by 1.18, 1.49, 2.11 fold and significant differences were observed in all groups (F=29.10, P<0.05). Compared with 0 hour group, the expressions of HSP47 mRNA were up-regulated by 1.56, 1.84, 2.86 fold in ARPE-19 cells stimulated by 5 ng/ml TGF-β2 for 12, 24 and 48 hours, and the differences were all significant (F=31.56, P<0.05); the expressions of protein were up-regulated by 2.08, 2.37, 2.80 fold, and the differences were all significant (F=49.18, P<0.05). The expressions of Col-Ⅰ mRNA were up-regulated by 1.57, 1.86, 2.78 fold and the differences were all significant (F=54.43, P<0.05), the expressions of protein were up-regulated by 1.38, 1.59, 2.16 fold and the differences were all significant (F=42.52, P<0.05).
ConclusionTGF-β2 may play a role in the pathologic process of PVR by promoting the expression of HSP47 and then increasing the synthesis and accumulation of Col-Ⅰ.
ObjectiveTo summarize the therapeutic targets of pancreatic cancer (PC).
MethodsThe related literatures about the therapeutic targets of PC were reviewed.
ResultsPC was one of the most challenging tumor in worldwide, and was characterized as a highly aggressive disease with poor overall prognosis and a high mortality rate. The hallmark of PC was its poor response to radio-and chemo-therapy. Current chemotherapeutic regimens could not provide substantial survival benefit with a clear increase in overall survival. Recently, several new approaches which could significantly improve the clinical outcome of PC had been described, involving signal-transduction pathways, immune response, stroma reaction, and epigenetic changes.
ConclusionsMany therapeutic targets are involved in the treatment of PC. As current therapies failed to significantly improve the progression and the survival of PC, new therapeutic approaches and clinical studies are strongly required.
Objective
To investigate the effect of subretinal fluid (SRF) with different grades of proliferative vitreoretinopathy (PVR) on bcl-2 oncoprotein expression in retinal pigment epithelium (RPE) cells and fib roblast (FB)．
Methods
Using immunohistological staining technique and Western-blotting method to detect the expression of bcl-2 protein in RPE cells and FB under the stimulation of SRF．
Results
The expression levels of bcl-2 increased in both types of cells to a certain extent compared with those of the control group 4 hours after the cells subjected to SRF； 36 hours later, the expression levels of bcl-2 of experimental groups decreased more quickly than those of the control group， and the control group showed relatively higher bcl-2 protein levels at the end of observation．
Conclusions
SRF may stimulate the e xpression of bcl-2 in RPE cells and FB under culture at early stage, but accel arate the declining of bcl-2 protein levels a certain time after subjected to SRF．
(Chin J Ocul Fundus Dis, 2001,17:58-60)
Objective
To investigate the cilinical value of indocyanine green angiography(ICGA) in patients with Vogt-Koyanagi-Harada syndrome(VKH).
Methods
Fundus fluorescein angiography(FFA) and indocyanine green angiography(ICGA) were used for comparative analyses in 26 cases(52 eyes)of VKH.
Results
In the acute stage of VKH,FFA revealed the multifocal leakage in the pigment epithelium and the multifocal serous retinal detachment,and the typical FFA manifestations disappeard following treatment．In the acute stage of the disease the ICGA showed:(1)numerous patchy areas of hypofluorescence and decreased flurescence in large and middle choroidal vessels(66.7%);(2)dilatation of the choroidal vessels(70.8%)and(3)in latephase of ICGA,the patchy areas of hyperfluorescence(79.2%).During the recovery stage of the disease,the abnormal undings in ICGA were resolved slower than those found in FFA.
Conclusions
ICGA may assist in providing valuable informations on choroidal circulation of VKH and be useful in evaluating the curative effects．
(Chin J Ocul Fundus Dis,20000,16:9-11)
