Objective Tissue engineering advance in supplying the reparative and reconstructive medicine with promising tissue engineered medical products(TEMPs) and the new therapy alternative. The related supervision and administration of TEMPs is being developed and the standard research of TEMPs is also in progress. The Food and Drug Administration(FDA) of the United States has treated TEMPs as combined products and supervised them according to the level of risk to patients. Lately, FDA has determined that the Center for Devices and Radiological Health (CDRH) should take charge of examination and approval of TEMPs, with the cooperation of the Center for Biological Evaluations and Research(CBER). The regulatory controls have been established respectively in European Union and Japan. In China, TEMPs are identified as medical devices combined with cells. The Department of Medical Device of the State Food and Drug Administration (SFDA) is responsible for the examination and approval of TEMPs, and National Institute for the Control of Pharmaceutical amp; Biological Products(NICPBP) is responsible for evaluation tests. The standards of TEMPs are formulated mainly by the American Society of Testing Materials(ASTM) and International Standardization Organization(ISO).
OBJECTIVE:To verify the safe dose of cephradine in intravitreal injection. METHODS:After injecting different doses of cephradine(100mu;g,200mu;g,250mu;g,300mu;g,400mu;g)into vitreous cavity of different group of rabbits the activities of the retinal enzymes (SDH,LDH )on different time (Id,3d, 7d ) were determined respectively, and the histological and ultrastructural changes of retinas were also observed simuhaneously. RESULTS:The activity of rellnal SDH and LDH was found to be decreased gradually with tbe icreasing of the dosage of intravitreal cephradine. The activities of SDH and LDH were found in the lowest level on tile 3rd and lsl day,but they recover to normal levels on tile 7th day after intravitreal in}eetion in 100mu;g,200mu;g groups,and still lower tban normal in the other groups. Histologically,retinal edema was found both in 100mu;g and 200mu;g groups,but degradation of retinal cells,and loss of cones and rods were round in the 250mu;g, 300mu;g and 400mu;g groups. CONCLUSION: The safe dose of intravitreal injection of cepbradlnc is 200mu;g. （Chin J Ocul Fundus Dis,1997,13:139-142 ）
Objective To investigate the effects of QUE on proliferation and DNA synthesis of cultured retinal pigment epithelium(RPE) cells with or without EGF. Methods With or without EGF, cultured RPE cells were treated with QUE by various concentrations(200,100,50,1mu;mol/L) and with QUE 200mu;mol/L at different times(24-168 hr), cells proliferation and DNA synthesis were evaluated by cell count method and the uptake of thymidine. The viability of cells was determined by trypanblue exclusion. Results The best concentration of QUE which inhibits proliferation and DNA synthesis of PRE cells was 200mu;mol/L. The significant inhibition effect of QUE occurred at 48hr, and the best inhibition of QUE occurred at 96hr. QUE had more powerful effect of antiproliferation on RPE cells, and the viability of RPE cells was over85%. Conclusion The results suggested that QUE could inhibit the proliferation of RPE cells in a dose-dependent and time-dependent manner, especially inhibit the proliferation induced by EGF stimulating. QUE had no cyto-toxic effect on RPE cells cultured in vitro. (Chin J Ocul Fundus Dis,1999,15:27-29)
Objective To observe the inhibitory effects and characteristics of intravitreal injection with bevacizumab on laser induced choroidal neovascularization (CNV).Methods Twelve male brown norway（BN）rats were divided into the bevacizumab group and control group with six rats in each group. One eye of rats were received a series of 8 diode laser esions around optic disc to induce CNV,then the rats in bevacizumab group and control group underwent intravitreal injection with 2 mu;l bevacizumab and ringer's lactate.On days 7,14,and 21，the morphology and leakage of CNV were observed by fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA).On day 21 after photocoagulation,the photocoagulated eyes were enucleated and processed for histopathologic examination, including hematoxylin and eosin (Hamp;E) staining and immunohistochemistry staining for vascular endothelial growth factor（VEGF）.Results On day 7 after photocoagulation,ICGA showed that CNV developed in the bevacizumab group and the control group. FFA showed that leakage intensity in the bevacizumab group was significantly lower than that in the control group，but the bevacizumab group gradually increased over time. The mean thickness of CNV significantly decreased in the bevacizumab group.The CNV in the bevacizumab group were negative for VEGF according to the result of immmuohistochemistry staining.Conclusions Early intravitreal injection with 2 mu;l bevacizumab can reduce the thickness of CNV and inhibit the leakage of CNV. However, bevacizumab could neither block the formation of CNV, nor suppress the permeability permanently. Combined other therapies with bevacizumab may be more potential to treat CNV effectively.
Objective To observe the influence of the indomethacin on the proliferative and invasive activity of OCM-1 human choroidal melanoma cells. Methods OCM-1 cells were cultured with different concentrations of indomethacin (25, 50, 100, 200, 400 mu;mol/L ), and their proliferation were assessed by methyl thiazolyl tetrazolium（MTT）, invasive behaviors were examined by cell invasion assays, expression of survivin and VEGF were evaluated by reverse transcriptase polymerase chain reaction（RT-PCR）, immunofluorescence staining, ELISA and western blot analysis. Result All concentrations of indomethacin in this study can inhibit the proliferation and invasion of OCM-1 cells in a time and dosage-dependant manner（MTT/24 h：F=19.642，P＜0.01；MTT/48 h：F=136.597，P＜0.01；MTT/72 h：F=582.543，P＜0.01；invasion assays：F=54.225，P＜0.01）. Immunofluorescence staining indicated that survivin and VEGF mainly expressed in the cytoplasm of OCM-1 cells. Survivin mRNA in OCM-1 cells was inhibited by 100, 200, 400 mu;mol/L indomethacin（F=16.679，P＜0.01）. The concentrations of survivin were (787.3plusmn;47.37), (257.0plusmn;26.21), (123.3plusmn;8.02) pg/ml in control group and 100, 400 mu;mol/L indomethacin groups, respectively. Survivin expression was also significantly down-regulated in indomethacin-treated cells by Western blot analysis.Indomethacin had no effects on VEGF expression in OCM-1 cells.Conclusions Indomethacin can inhibit proliferation and invasion of OCM-1 cells in vitro,down-regulated expression of survivin may be the mechanism.
Objective To observe the effect of medicineinduced posterior vitreous detachment (PVD) on proliferative vitreoretinopathy (PVR). Methods PVR was induced in the left eyes of 24 pigmented rabbits by intravitreal injection with platelet rich plasma. The rabbits were randomly divided into two experimental groups (group A and B) and one control group with 8 eyes in each group. Three hours later, the eyes in group A and B and the control group underwent intravireal injection with 1 U plasmin 0.05 ml+20 U hyaluronidase 0.05 ml, plasmin 0.1 ml, and balance salt solution 0.1 ml, respectively. The grade of PVR was recorded 1, 7, and 28 days after the intravitreal injection, and the eyes were examined by flash electroretinogram (FERG), B-scan, and retinal histopathological examination. Results The PVR models of rabbit eyes were induced successfully. On the 7th day after injection, complete and partial PVD was found in 5 and 3 eyes respectively in group A; partial PVD in 5 eyes and no complete PVD was observed in group B; there was no PVD in the other 3 eyes in group B and also in the eyes in the control group. On the 28th day after intravitreal injection, PVR grade of group A and B were both obviously lower than that of the control group（D=75.6, 98.9；P=0.003，P=0.011）; On the 7th and 28th day after injection, the b-wave amplitude in group A and B was significantly higher than that in the control group; PVR grade of the PVD eyes was lower than that of nonPVD eyes; PVR grade of the complete PVD eyes was only 0～1. Conclusions Three hours after the PVR models of rabbit eyes were induced, complete PVD induced by intravitreal injection of plasmin combined with hyaluronidase could prevent the development of PVR of rabbit eyes in some degree; partial PVD induced by plasmin alone or combined with hyaluronidase could relieve the development of PVR.
Objective To investigate the retinal toxicity and verify the safe dose of intravitreal injecting fluconazole. Methods Twelve healthy adult white rabbits were divided at random into 6 groups：a normal control group and 5 groups received intravitreal injection of a single dose of fluconazole ranging from 10 to 200 mu;g respectively.Retinal toxicity was examined by ophthalmoscopy, electroretinography, light and transmission electron microscopy (TEM) on the third and fourteenth day after injection. Results The ultrastructures of the retinal tissues of the normal control group and fluconazole 10～150 mu;g groups were normal on the third and fourteen day after injection.The light microscopy and TEM showed that cells of all the retinal layers in the 200 mu;g group revealed apparent degenerative changes on the fourteenth day after injection, and the light microscopic picture showed the vacuolar degeneration of outer segments of photoreceptors, the nuclei in outer nuclear layer drop out into inner segments, the vacuolar degeneration of nerve fiber layer, and the proliferation of pigment epithelium. TEM revealed expansion of paranucl eus space and karyopyknosis of the bipolar cells, the swelling of nerve fibers and disappearance of the synapses in the inner plexiform layer, the vacuolation and disappearance of microvilli of the pigment epithelium cells. Conclusion The safe dose of fluconazole injected intravitreally should be 100～150 mu;g. (Chin J Ocul Fundus Dis，2000，16：139-212)
Objective To investigate the retinal toxicity and verify the safe dose of intravitreal injection of nonsteroid anti-inflamatory drug,diclofenac sodium.Methods Twenty-eight healthy adult white rabbits were divided at random into 7 groups and received in every right eye the intravitreal injection of a single dose of diclofenac sodium solution ranging from 0.4-0.1 mg/0.1ml respectively ,the left eyes were regarded as conreol ones.Before injection and on the 1st,3rd,7th,14th,21st,and 28th day after injection the electroretinography on both eyes was examined.On the 28th day after injection the retinas of two rabbits of every group were examined by using light microscopy.On the 10th and 30th day after injection the retinal tissues around the optic nerve sisk of two eyes from every group at random were tested by using transmission electron microscopy.Results The retio of amplitude ofb wave of electroretinography in 0.4mg and 0.5mg groups had no sighnificant difference from groups before injection,the retinal tissues showed no structural changes in light and ecectron microscopy examination.The ratio of amplitude ofb wave of photoptic electroretinogrphy in 0.6mg groups in the early stage after injection was markedly reduced（P＜0.05）and returned to that before injection with time,reversible change of the edematou retina was discovered.The ratio of amplitude of b wave of electroretinography in 0.7-1.0mg groups was distinctly descreaded after injection（P＜0.05 or P＜0.01）,the cells of all the retinal layer revealed apparent and irreversible damage.Conclusion The largest dose of safety of intravitreal diclofenac sodium should be not more than 0.6mg.The toxic effect of intravitreal diclofenac sodium on retina is concerned mostly to cones and rods.
Objective To observe the efficacy of the anti-tumor necrosis factor-alpha; monoclonal antibody (TNF-alpha; MCAb) in the treatment of experimental autoimmune uveoretinitis (EAU). Methods EAU animal models were induced by interphotoreceptor retinoid-binding protein (IRBP) R16 peptide with immunization. The rats were divided into 2 groups according to the injection times. TNF-alpha; MCAb was administered intravenously on day 6 or 4, 6 and 8 post-immunization respectively, and then to observe the clinical expression by slit-lamp microscope. Meanwhile, take the rats which did not accept TNF-alpha; MCAb as control group. Delayed type hypersensitivity (DTH) responses were measured on day 13 post-immunization of IRBP R16; the rats were killed on day 14 post-immunization of IRBP R16, and then enucleated the eyes for histopathological examination. To detect the cytokine level of IFN-gamma;, IL-4 in serum and IFN-gamma; in aqueous humor by enzyme-liked immunosorbent assay (ELISA) on day 14 post-injection. The hyperplasia responses of antigen specific lymphocyte of draining lymph node cells were detected. Results The TNF-alpha; MCAb group had mitigated ocular inflammation and decreased pathological grades compared with the control group; the IFN-gamma; concentrations in aqueous humor and serum were decreased, IL-4 was increased in serum; DTH responses were decreased; the hyperplasia responses of draining lymphocytes to IRBP R16 peptide were decreased, all the differences were statistically significant (P＜0.01). The rats accepted TNF-alpha; MCAb thrice had much better curative effect than the rats injected once (P＜0.05). Conclusions Injection of TNF-alpha; MCAb can inhibit ocular inflammation and specific immune cells of EAU remarkably and change the Th1/Th2 balance. Many times injections of TNF-alpha; MCAb were more effective than once.