Background Retinal vein occlusion is a common retinal vascular diseases.Thromblysis and anticoagulation therapies are main approaches.However,systemic thrombolysis is relatively inefficient,and it often enhances the risk of hemorrhage.Objective This study was to investigate the therapeutic effects of PLM-ΔK,a kringle deficiency mutant of plasmin,on photochemically induced branch retinal vein occlusion (BRVO) after intravitreal injection.Methods BRVO models were established by the combination of caudal vein injection of Rose Bengal with argon laser radiation of periphery area of retinal veins in SD rats.Forty model rats were randomized into balance salt solution (BSS) group and 0.01 U,0.02 U,0.03 U PLM-ΔK group,and 10 μl corresponding drug was intravtreally injected 12 hours after modeling.Ophthalmoscopy and fundus fluorescein angiography (FFA) were performed to observe the change of retinal veins.The animals were sacrificed 3 days after intravitreal injection,and hematoxylin and eosin staining was used for the histopathological and ultrastructural examination of retinas.The retina of the rats was isolated for the stretched preparation of retina.The expressions of fibronectin (FN) and laminin (LN) in eyeball wall were assayed by immunofluorescence technology.The use and care of the animals complied with Statement of the Association for Research in Vision and Ophthalmology.Results The revascularization of over 2 retinal veins was found in 0,3,6 and 8 rats in the BBS group and 0.01 U,0.02 U,0.03 U PLM-ΔK group 3 days after intravitreal injection,respectively,showing a significant difference among the groups (x2=9.635,P =0.022),and the rat number with revascularization in 0.01 U PLM-ΔK group was not significantly different from that in BSS group (Z=-1.558,P =0.119),but the difference between 0.03 U PLM-ΔK group and 0.01 U PLM-ΔK group was significant (Z=-2.762,P=0.006).In the third day after intravitreal injection,retinal vein thrombus were found in the BSS group under the light microscope,and angiogenesis was seen on the retinal flatmount nuclear.In the 0.03 U PLM-ΔK group,posterior vitreal detachment was exhibited under the light microcope,and no retinal new vessel and cell damage were seen.FN was strongly expressed in the inner limiting membrane (ILM) layer,photocyte layer,outer limiting membrane (OLM) layer,choroid and scleral layer,and LN was expressed mainly in the ILM,OLM and scleral layer in the BSS group.However,the expression intensities of FN and LN were obviously weakened in the 0.03 U PLM-ΔK group.Conclusions Intravitreal injection of PLM-ΔK can enhance the reperfusion of occluded branch retinal vein and serve as a potential therapeutic drug for BRVO.Also it can permeate into choroid after intravitreal injection to degradate FN and LN.

Objective To master the technique of mouse embryonic stem (ES) cells differentiate into endothelial cells,which would be a new therapeutic approach for cardiovascular disease.Methods Expression of selfrenewal marker genes in E 14 cells was assessed.Expression of vascular endothelial growth factor receptor 2 (Flk 1) in monolayer differentiation on day 4 and vascular endothelial cadherin (VE-cadherin) on day 8 were detected.On day 8,differentiation cells were also observed under phase contrast microscopy (PCM) and transmission electron microscope (TEM).ES cells and endothelial-specific molecular markers were assessed by RT-PCR at different time-points.Results As self-renewal marker genes were expressed in E14 cells,E14 cells was identified to maintain their selfrenewal pluripotency.The marker gene of letarl,Flk1 was expressed on differentiation day 4.On differentiation day 8 the marker gene VE-cadherin was expressed and as observed under PCM endothelial cells with spindle shape and TEM with Weibel-Palade body,thus were the major populations generated after VEGF induction,and E14 cells were confirmed differentiated into mature endothelial cells.The expressions of genes octamer binding transcription factor 4 (Oct4),Flk1 and VE-cadherin were detected on differentiation day 2,4,6,8 and 10.Conclusions As VE-cadherin gene was expressed in monolayer on differentiation day 8,E14 cells were confirmed differentiated into endothelial cells,which would be a new therapeutic approach for cardiovascular disease.

Objective To study the putative mechanisms underlying fetal alcohol syndrome by comparative protein-profile analysis between normal and ethanol-treated zebrafish embryo with twodimensional electrophoresis (2-DE).Methods Zebrafish embryos were exposed in 400 mmol/L ethanol at dome stage for 3 hours,and then ethanol-induced abnormalities were observed.Proteomes of zebrafish embryos at early stages including zygote stage,dome stage,shield stage and 5-somite stage,were separated by 2-DE.The subtraction analysis method was applied to eliminate the interference from maternal derived proteins.The ethanol-treated embryos at 5-somite stage was analyzed by 2-DE,and the protein profile was compared with that generated from control embryos at the same stage.The data obtained from 2-DE analysis were verified by in-situ hybridization.Results 400 mmol/L ethanol treatment caused axial malformation (62%) and cyclopia (60%) in zebrafish embryos.The 2-DE analysis showed that the expression of Collagen2al (Col2a1) and TAR DNA binding protein (TDP) was decreased in 12 hours post fertilization (12 hpf) ethanol-treated embryos by 81% and 73%,respectively.The in-situ hybridization also demonstrated that the expression of Col2al in axial mesoderm was reduced by ethanol treatment at the same stage.But for 24 hpf ethanoltreated embryos,the expression of Col2al in axis recovered to a comparable level to that in control embryos,while the structure of neural tube was disrupted severely by ethanol exposure.Conclusions It is suggested that the expressions of Col2al and TDP were disrupted by ethanol during early stage,which might induce the zebrafish developmental abnormalities.The ethanol interference on early expression of Col2al is supposed to be one of the major reasons leading to later abnormalities of axis and neutral tube.

Objective To establish a zebrafish IGFBP-2 gene knock-down model by morphilino modified antisense oligonucleotide injection, so as to investigate the abnormal phenotypes of heart and vessels in early stage of zebrafish development and the expression of zebrafish cardiogenesis related genes. Methods The spatiotemporal expression of IGFBP-2 gene in early stage of zebrafish development was testified by whole mount in situ hybridization with antisense RNA IGFBP-2 probe. The IGFBP-2 morpholino (IGFBP-2 MO) that especially inhibited the gene promoter and standard control morpholino (Con-MO) were designed and synthesized by Gene-tools Corporation. Four different concentration gradients (0.05, 0.10, 0.25 and 1.0 mmol/L) were set as IGFBP-MO injection groups with 0.25 mmol/L Con-MO injection group and wild type group as controls. Contribution to the incidence of heart abnormal phenotypes and mortality rate induced by 4 different IGFBP-2 concentrations injection group was recorded and compared with 2 control groups. Heart abnormal phenotypes at different developmental stages in 0.25 mmol/L IGFBP-2 injection group were observed in detail. To validate the effectiveness of IGFBP-2 MO, the expression of enhanced green fluorescence presented by wild type zebrafish embryos at 12hpf which received single injection of IGFBP-2 EGFP recombinant plasmid and those co-injected with Con-MO or IGFBP-2 MO were detected. To investigate the regulation relationship between IGFBP-2 gene and other cardiogenesis related genes, expression of atrium specific marker gene Amhc was detected in IGFBP-2 MO and wild type group by in situ hybridization. Ventricle specific green fluorescence of Vmhc-EGFP transgenic zebrafish embryos whose IGFBP-2 gene was knocked-down were compared with those untreated. Zebrafish peripheral vascular development in the IGFBP-2 MO group was also checked out by micro-angiography. Results Whole mount in situ hybridization revealed that IGFBP-2 gene expressed in turn at eyes, midbrain and then focused on liver in early stage of zebrafish development. The micro-injection of 0.25 mmol/L IGFBP-2 MO resulted in heart malformation in nearly 60% of all injected zebrafish embryos. Heart malformation phenotypes included slow heart beat, pericardial edema, weak ventricle systole contraction and heart tube looping disorder. Some of them represented atria dilation, blood regurgitation and ciculation obstruction. Wild type zebrafish embryos that received single injection of IGFBP-2 EGFP plasmid DNA or co-injected with Con-MO presented strong enhanced green fluorescence at 12hpf, meanwhile, the fluorescence was barely seen in the embryos co-injected with IGFBP-2 MO. This strongly validated the gene specific knock-down effect of IGFBP-2 MO. Amhc was down-regulated at 48hpf in IGFBP-2 MO group. Vmhc-EGFP transgenic zebrafish down-regulated by IGFBP-2 gene also resulted in attenuated expression of ventriclar-specific green fluorescence protein at 48hpf. Intersegmental blood vessels of IGFBP-2 MO group by micro-angiography at 60hpf demonstrated an sparsate and chaos image, which suggested that IGFBP-2 gene expression was involved in the regulation of normal vascular development. Conclusions Micro-injection of IGFBP-2 MO is an efficient way to knock-down IGFBP-2 gene in zebrafish embryos. IGFBP-2 gene expression down-regulation leads to heart and vessels maldevelopment and have an impact on the expression of cardiogenesis related genes of zebrafish embryos as well. In short, IGFBP-2 plays a critical role in the normal cardiovascular development of zebrafish embryos.

Objective To study the effect of retinal dehydrogenase type 2 inhibitor (4-diethylaminobenzaldehyde,DEAB) on embryonic CSrdiac develclpment of zebrafish model with retinoic acid(RA)deficiency. Methods Zebrafish embryos were treated with DEAB at various concentrations including 1×10~(-6),5×10~(-6),10×10~(-6),25×10~(-6)mol/L at 5,8 and 10.3 hours post fertilization,respectively.The effects of DEAB on the embryonic development were assessed under microscope.1×10~(-9)mol/L exogenous RA was then added to detect the antagonistic effect against DEAB.The abnormal cardiac phenotype,heart rate and ventricular systolic fraction were observed and analyzed between wild type and DEAB treated groups.The expression of specific cardiac gene, natriuretic peptide precursor A,was monitored by whole-mount in situ hybridization to demonstrate the effect of RA signaling on early cardiac development. Results The survival rate of zebrafish embryos declined with the increase of DEAB concentration at different developmental stage.The percentage of abnormal embryos reached 100% when DEAB over 5×10~(-6)mol/L.1×10~(-9) mol/L exogenous RA could eliminate the teratogenic effect of DEAB(≥5×10~(-6)mol/L).DEAB treated embryos presented abnormal cardiac phenotype,including tubular heart,incomplete D-loop,abnormal atrioventricular development,regurgitation,slow blood flow and weak heart beat.The difference of heart rate and ventrieular systolic fraction between wild type and RA deficiency embryos was of statistical significance(P<0.05).The natriuretic peptide precursor A expression remained in the ventricle,but reduced obviously in the atrium with RA signaling deficiency. Conclusions The effects of DEAB on the embryonic development are dose-dependent and time-dependent,and could be rescued by exogenous RA.RA signaling plays a critical role in several key stages of early cardiac development and natriuretie peptide precursor A expression.

Background The vitreoretinal traction plays a critical role in the formation of macular hole and cystoid macular edema.Enzymatic vitreolysis has potential in relieving vitreoretinal traction as a simple and less invasive method in comparison with pars plane vitrectomy.ObjectiveThis study is to investigate the effects of plasmin mutant with kringle domains deficiency(Plm△K)on vitreoretinal interface in new Zealand white rabbits.Methods Plm△K was prepared through activating plasminogen mutant with Kringle domains deficiency (Plg△K) by tissue plasminogen activator (tPA).100μL of Plm△K at the dose of 0.5,1.0 and 1.5μmol/min was injected respectively into the vitreous of 48 New Zealand white rabbits and 16 eyes for each dose.B-scan and optical coherence tomography (OCT) were performed to detect the structure variety at the vitreoretinal interface in 1 day and 7 days after injection.The gross anatomy analysis with triamcinolone acetonide fine particle suspension,as well as histopathological examinations by scanning electron microscopy,was performed in the different time points mentioned above.Results Two peptide chains were determined with the relative molecular weight about 26000 and 5000 by the gel imaging analysis of reduced SDS-PAGE.Separation of the posterior vitreous cortex from retina was found after intravitreous injection under the B-scan and OCT.The ultrastructure change of vitreoretinal interface as well as the examination of fine particle suspension by triamcinolone acetonide demonstrated the same outcome.The degree of remnants of vitreous cortex showed the negative correlation with the dosage of Plm△K (r=-0.9516,P=0.048).No significant correlation was found between the degree of remnants of vitreous cortex and the action time(r=-0.720,P=0.470).There was no obvious morphological difference in outer layer of retina between control eyes and Plm△K-treated eyes.No drug-related adverse event was found after intravitreous injection of Plm△K.Conclusion Intravitreous injection of Plm△K alone can induce complete separation of vitreous from retina.This procedure is safe and effective.

Whole mount in situ hybridization with BHC80 RNA probe showed that BHC80 was expressed in zebrafish central nervous system. Morpholino-modified antisense oligonucleotide was injected into zebrafish zygotes to knock down BHC80 expression. BHC80 knockdown resulted in striking decrease of erythrocytes and accumulation of erythrocytes at PBI. Further investigation of embryonic erythrocytes marker βe3 globin and hematopoiesis transcription factors gata1, c-myb and lmo2 by in situ hybridization showed that the erythroid progenitors marked with gata1 in BHC80 knockdown embryos were high proliferation and their differentiation were delayed, which led to decrease of erythrocytes and accumulation of erythrocytes at PBI. Both in situ hybridization and microangiography indicated that vasculature pattern of BHC80 knockdown embryos were almost normal.

Objective To construct a folic acid deficient model in zebrafish and to observe the axial development in folic acid deficient embryos, so as to probe the mechanism by which folic acid deficiency induces abnormal development of axis. Methods We constructed the folic acid deficient zebrafish model by both using the antagonism of dihydrofolate reductase (MTX) and knocking-down dihydrofolate reductase gene. Then we observed the axial excursion of folic acid deficient embryos at 17 hpf under microscope. We labeled and observed the positions of liver, spleen and heart by using whole-mount in situ hybridization with specific antisense RNA probes. The expressions of some genes, which are down stream factors of Nodal signal pathway and important for axial development, were detected by whole-mount in situ hybridization and Real-time PCR. Results Parts of folic acid deficient embryos had axial excursion and abnormal positions of liver, spleen and heart. The expressing intensities of ntl and gsc appeared normal in folic acid deficient embryos, but the expressing spatial patterns were abnormal, which revealed the malformation of axial mesoderm. Conclusions Folic acid deficiency induced the abnormal development of axis and the malformation of axial mesoderm. Folic acid deficiency had no obviouse effect on Nodal pathway.

Objective: To evaluate the frequency of MSI in epithelial ovarian tumors and its relationship with clinicopathologic features. Methods: Ninety fresh specimens of epithelial ovarian tumors, including 74 primary and 16 secondary tumors, were collected. Microsatellite analysis was carried out using 5 mono- and dinucleotide markers from the National Cancer Institute Consensus Panel by fluorescence-labeled polymerase chain reaction. Results: Of 90 epithelial ovarian tumors analyzed, 18 demonstrated a high level of microsatellite instability (MSI-H), 30 demonstrated a low level of microsatellite instability (MSI-L), and the remaining 42 exhibited microsatellite stability (MSS). Frequency of microsatellite instability (MSI) at loci BAT-25 was higher than that at any other loci. No correlation was found between MSI level and patient age, tumor type, tumor differentiation (P>0.05). But the microsatellite instability-high phenotype correlates with clinical stage.It tended to occur more frequently in early-stage tumors (P=0.03). Conclusion: The frequent MSI in epithelial ovarian tumors suggests that it is an early event to involve in the development of epithelial ovarian tumors.

Aim To produce poly (lactic-co-glycolic acid) (PLGA) microspheres, containing a staphylokinase variant (K35R, DGR) with reduced immunogenecity and antiplatclet aggregation activities,which allowed the preservation of protein stability during both particle processing and drug release.Methods DGR-loaded microspheres were fabricated using a double emulsion-solvent evaporation technique. The effects of preparative parameters, such as stirring rate, polymer concentration, and the excipients of both internal and external aqueous phase (W2 ), on DGR encapsulation efficiency and microsphere characteristics were investigated. In vitro and in vivo release of DGR were conducted and the cause for instability of DGR during release was also investigated. Results Moderate ultrasonic treatment of aqueous DGR/dichloromethane mixtures caused approximately. Eighty four per cent DGR denaturation.However, the activity recovery of DGR almost amounted to 100% when 2% polyvinyl alcohol (PVA) was added into the aqueous phase. It was found that NaCl in the external water phase significantly increased DGR encapsulation efficiency. Furthermore, NaCl in the external water phase played a role in determining size and surface morphology of microsphere. In vitro release test showed a burst release of DGR from microspheres, followed by sustained release of 50% total activity over 15 days. In vivo experiments showed that DGR released from microspheres sustained 5 days. Denaturation of DGR within microspheres might be resulted from acidic microclimate. Conclusion The stability of DGR was effectively protected during microencapsulation and a relatively high encapsulation efficiency of DGR was obtained. PLGA microspheres could be an effective carrier for DGR.