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Background The primary management for nasolacrimal duct obstruction is the combination of lacrimal duct probing with lacrimal duct stent implantation.However,conventional implant is undegradable.New degradable lacrimal duct prosthesis based on biopolymer materials is a research hotspot.Objective This study described herein a preparation method of novel degradable lacrimal duct prosthesis and its application.Methods A new degradable lacrimal tube stent was prepared with compound of poly L lactic acid (PLLA) and polycaprolactone (PCL) (6:4) and 15％ polyethylene glycol (PEG).Thirty-two Japanese rabbits aged 3-4 months were randomized into postoperative 1-week group,postoperative 4-week group,postoperative 8-week group and postoperative 16-week group.The degradable lacrimal tube stents were inserted into the lacrimal ducts of the left eyes of the rabbits.The prosthesis was removed in corresponding time points according to grouping,and the integrity and weight of the prosthesis were evaluated.The mucosal findings of the operative eyes were examined under the endoscope,and the histopathological and inflammatory reaction was observed by hematoxylin & eosin stain.The ultrastructure of the lacrimal mucosal surface was examined under the scanning electron microscope.The use and care of the rabbits complied with the Regulations for the Administration of Affair Concerning Experimental Animals by State Science and Technology Commission.Results The new degradable PLLA:PCL+15％ PEG lacrimal duct stents were smooth,flexible and hydrophilic tubes.The removed tubes were intact in the postoperative 1-week group,however,the rupture of the tubes appeared in the postoperative 4-week group,while discrete pieces of the tubes were seen in the postoperative 16-week group.The weight-loss rates of the tubes were (13.44±6.59)％,(23.96±6.33)％,(55.08-± 6.55) ％ and (78.00±8.74) ％ in the postoperative 1-week group,postoperative 4-week group,postoperative 8-week group and postoperative 16-week group,respectively,and the weight-loss rate of the tubes was significantly higher in the postoperative 16-week group than those in the postoperative 8-week group (q =4.27,P＜0.05).No significant difference was found in the weight-loss rate of the tubes between postoperative 1-week group and postoperative 4-week group (q =1.71,P＞0.05).The edema,hyperemia and mild proliferation of the lacrimal mucosal were exhibited in the eyes of the postoperative 4-and 8-week groups,and the mucosal findings were almost normal in the eyes of the postoperative 16-week group under the endoscope.Histopathological examination showed a large number of inflammatory cells in the postoperative 1-,4-and 8-week groups.However,few inflammatory cells were seen in the postoperative 16-week group.Mucosal folds,microvillus decrease and disorder were displayed in the lacrimal duct of the postoperative 8-week group,and no evident abnormality was seen in the lacrimal duct mucosal surface.No postoperative complication occurred in all the rabbits.Conclusions PLLA:PCL+15％ PEG lacrimal duct stent has an appropriate degradation speed and good biocompatibility after implant in rabbits,and its decay period of mechanical strength could match lacrimal duct healing period.
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Background Leber hereditary optic neuropathy (LHON) is mitochondrial DNA (mtDNA) disease and mainly leads to optical nerve degeneration.Its primary mechanism is synthesis disorder of DN4 protein due to variation of mtDNA 11778 locus.So to construct a vector with exogenous normal ND4 and transfect into mitochondria is a key of gene therapy for LHON.Objective This study was to investigate the in vitro transfection of adeno-associated virus (AAV)-ND4 gene into mitochondria.Methods Human renal epithelial cell lines transfected adenovirus E1A (293 cells) were regularly cultured and divided into two groups.Framework plasmids of recombinant AAV-ND4 or simple AAV2 were added to the cell medium respectively.The expression of ND4 in cells were located 12,24,36 and 48 hours after transfected by Y03 dual fluorescent quantum dots staining.The positive response for ND4 showed the green fluorescence.Results Cultured 293 cells grew well with 80％ confluence.Abundant green fluorescence particles were seen in cytoplasm in the AAV-ND4 transfected group,but only red fluorescence from mitochondrial protein was seen in the simple AAV transfected group under the fluorescence microscope.Conclusions Exogenous ND4 protein can been successfully transfected into mitochondria using the ND4 gene constructed AAV.This result provides experimental evidence for the further study on gene therapy of LHON.
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Mobile learning has the characteristics of mobility,timeliness,network and virtu-ality. We developed virtual hospital suitable for mobile devices and organized students in to a network. Through early training,clinical case screen,learning objective fix,learning process and results evaluation,mobile devices were employed to do problem-based learning,which is conducive to the integration of theory with practice,the shifting from discipline-centered to system-based courses and the improving of utilization rate of learning resource.
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Background Researchers are paying increasing attention to the effect of cellular senescence in vascular dysfunctional diseases,and it is hypothesized that cellular senescence may also be involved in the development of diabetes related vascular complications.The outstanding feature of cellular senescence is the upregulation of beta-galactosidase.Objective This study was to investigate the effects of high glucose on cell senescent in vitro and in vivo on bovine retinal endothelial cells (BRVECs) and mouse retina.Methods BRVECs were cultured and passaged,and the seventh generation of cells were employed in this study.The cells were divided into the control group and the high glucose culture group and cultivated using M199 medium containing 5.5 mmol/L or 25.0 mmol/L glucose,respectively.5-bromine-chlorine-4-3-indole-beta D galactose glucoside (X-Gal) staining was used to examine the expression of beta-galactosidase in the cells.Diabetic models were established in the SPF male C57BL/6J mice aged 8-10 weeks by intraperitoneal injection of streptozotocin (STZ),and the age-and gendermatched normal mice served as controls.The mouse retinas were collected and starched in the 48-well plates 3 months later.X-Gal staining was employed to calculate the positive cells.Results BRVECs grew well 24 hours after culture but showed irregular arrangement.Forty-eight hours later,the cells reached confluence with a tight connect.The ratios of positive BRVECs and total cells were (51.4±5.4) ％ and (36.6-±3.8) ％ in the high glucose culture group and the control group,with a significant difference between the two groups (t =-3.204,P =0.033).The number of positive cells for X-Gal in mouse retinas was (94.0± 15.1) /field in the diabetic group,which was higher than that in the control group ([60.0 ± 5.7]/field) (t =-2.974,P =0.041).Conclusions High glucose environment accelerates senescence of retinal cells,and high glucose induces premature cell senescence,which likely plays an important role in the pathogenesis of diabetic retinopathy.
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Objective To investigate the technique and application of nasolacrimal duct imaging using MR hydrography.Methods Eight healthy volunteers(16 lacrimal ducts)and 17 patients affected by primary epiphora(32 lacrimal ducts)underwent MRl with three.dimensional fast recovery fast spin echo (3D-FRFSE)MR dacryocystography(MRD)sequence after sterile saline solution had been instilled into the conjunctival sac.For all patients affected by primary epiphora,FRFSE T2-weighted oblique coronal and axial images were obtained after MRD.All patients(32 lacrimal ducts)underwem lacrimal endoscopy.which served as a standard of reference for confirming MR findings.Results Eight cases of 16 normal lacrimal passages were showed by MR hydrography with administering topical sterile saline solution,which demonstrated the lacrimal sac well and whole course of the nasolacrimal duct.Endoscopic findings confirmed nasolacrimal duct obstruction secondary to chronic non-specific inflammation:the color of the mucosa of the nasolaerimal ducts was grey-red,and the obstructive sinuses were filled with nonelastic grey-white membrane.The accuracy of 3D-FRFSE MRD sequence in diagnosing obstructive level was 78%(25/32). The lacrimal ducts above the obstructive level showed watery hypo-intensity on 3D-FRFSE MRD.and the lacrimal ducts below the obstructive level could not be showed.Abnormal findings were presented in all cases of obstructive nasolacrimal ducts with Axi-FRFSET2 WI and Cor-FRFSET,WI sequences:long T2 fluid signals were seen in the lumens of tlle lacrimal sac and(or)nasolacrimal duct above the obstructive level. equal or slightly long T2 soft-tissue signals were seen in the lumens of the nasolaerimal duct below the obstructive level.and the mucosa of the ducts thickened Conclusion MR imaging performed after the topical administration of sterile saline solution can reveal normal nasolacrimal duct and is feasible in evaluating obstructive nasolacrimal ducts.
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The effects of different concentrations of vascular endothelial cell growth factor (VEGF) on the fibrovascular ingrowth into rabbits hydroxyapatite orbital implant were investigated. Twelve New Zealand white rabbits were divided into 3 groups and received hydroxyapatite orbital implant surgery in their right eyes. Before and after the operation, the implants were treated with 10 ng/ml VEGF, 100 ng/ml VEGF, or normal saline as control group. The animals received technetium bones scan at 2, 4, and 6 weeks postoperatively. The mean radioactivity counts within region of interest (ROI) of the surgery eye (R) and the non-surgery eye (L) in the same animal were tested, and the R/L ratios were calculated. The implants were harvested at 6th weeks and examined histopathologically. The results showed that at second week, there was no significant difference in mean R/L ratios between VEGF group and control group (F=2.83, P=0.111); At 4th week (F=7.728, P=0.011) and 6th week (F=7.831, P=0.011) postoperatively, the mean ratios in VEGF groups were significantly higher than that in control group. At 6th week postoperatively, the fibrovascularization rates in VEGF groups were higher than in control group significantly (F=8.711, P=0.008). It was suggested that VEGF could promote the fibrovascular ingrowth into hydroxyapatite orbital implant, thus might shorten the time required for complete vascularization of the HA orbital implant.
Subject(s)
Eye, Artificial , Hydroxyapatites , Neovascularization, Physiologic/drug effects , Orbit/blood supply , Orbital Implants , Random Allocation , Vascular Endothelial Growth Factor A/pharmacologyABSTRACT
The effects of different concentrations of vascular endothelial cell growth factor (VEGF) on the fibrovascular ingrowth into rabbits hydroxyapatite orbital implant were investigated. Twelve New Zealand white rabbits were divided into 3 groups and received hydroxyapatite orbital implant surgery in their right eyes. Before and after the operation, the implants were treated with 10 ng/ml VEGF, 100 ng/ml VEGF, or normal saline as control group. The animals received technetium bones scan at 2, 4, and 6 weeks postoperatively. The mean radioactivity counts within region of interest (ROI) of the surgery eye (R) and the non-surgery eye (L) in the same animal were tested, and the R/L ratios were calculated. The implants were harvested at 6th weeks and examined histopathologically. The results showed that at second week, there was no significant difference in mean R/L ratios between VEGF group and control group (F=2.83, P=0.111); At 4th week (F=7.728, P=0.011) and 6th week (F=7.831, P=0.011) postoperatively, the mean ratios in VEGF groups were significantly higher than that in control group. At 6th week postoperatively, the fibrovascularization rates in VEGF groups were higher than in control group significantly (F=8.711, P=0.008). It was suggested that VEGF could promote the fibrovascular ingrowth into hydroxyapatite orbital implant, thus might shorten the time required for complete vascularization of the HA orbital implant.
Subject(s)
Animals , Rabbits , Eye, Artificial , Hydroxyapatites , Neovascularization, Physiologic , Orbit , Orbital Implants , Random Allocation , Vascular Endothelial Growth Factor A , PharmacologyABSTRACT
Chloridion participated in various kinds of biological function, such as cellular immunologic response , cell migration, cellular proliferation and differentiation, apoptosis. This kind of functional multiplicity corresponded with different gene encoding different chloride channel. It indicated that chloride channel function change or depletion concerned with many kinds of corneal disease. Therefore, the study of corneal chloride channel was very important This article summarized the effect of corneal chloride channel and its advances, and investigated the relationship between corneal disease and chloride channel.
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Objective To observe the expression of matrix metalloproteinase-9 (MMP-9), its tissue inhibitor of matrix metalloproteinase (TIMP-1), inducible nitric oxide synthase (iNOS) and contents of nitric oxide (NO) in the ocular tissues of Sprague-Dawley (SD) rats with endotoxin induced uveitis(EIU). Methods Ninety SD rats were randomly divided into experimental (81 rats) and control group (9 rats). The model of EIU was induced in rats in experimental group by injecting with lipoplysaccharide (LPS) 200 ?l into the hind feet pads, while the rats in the control group were not injected. Nine rats were executed 0, 6, 12, 18, 24, 48, 72, 96 hours and 7 days, respectively, after injecting with LPS; the NO content and concentration of protein in the aqueous humor in blood plasma, aqueous humor, and uveal tissues were detected. The expressions of MMP-9, TIMP-1 and iNOS in the ocular tissues were detected by immunohistochemistry, and the average absorbance (A) value was evaluated by computer medical image analysis system. Results iNOS, MMP-9 and TIMP-1 expressed in the epithelial cells of iris and ciliary body and exudated inflammatory cells of rats. The concentration of protein in the aqueous humor, the contents of NO in blood plasma, aqueous humor, and uveal tissues, and A value of MMP-9 had obvious relativity with the inflammatory extent, while no positive correlation was found between the inflammatory extent and the A value of iNOS and TIMP-1. Expression of iNOS was found 6 hours after injection, reached the peak after 12 hours, and then dropped gradually. The expression of TIMP-1 could be seen 24 hours after injection, and reached its peak after 72 hours. Conclusion The content of NO and expressions of iNOS, MMP-9 and TIMP-1 changes from the beginning and during the development of EIU, which suggests that NO, iNOS, MMP-9 and TIMP-1 are involved in the pathologic process of EIU.