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Objective:To understand the prevalence and epidemiological characteristics of glaucoma among people over 40 years old in rural areas of Chongqing.Methods:From August to October 2018, a stratified cluster random sampling method was used to investigate the cases of glaucoma among people over 40 years old in a rural population of the Rongchang and Qijiang Districts in Chongqing.The subjects had been living in the local area for over ten years.Basic information for each patient, including gender and age was documented, and their visual acuity and intraocular pressure were routinely measured.The Van Herick method was used to evaluate the depth of the central and peripheral anterior chamber, a preset lens was used to examine the fundus, and the cup to disc ratio(C/D) of the optic disc was emphasized.All suspected glaucoma patients underwent further standard glaucoma examinations.This study protocol was approved by the Ethics Committee of the First Affiliated Hospital of Army Medical University.Results:A total of 4 680 people were identified, and 4 073 respondents participated in the survey, and the response rate was 87%.The prevalence of glaucoma was 1.72% (70/4 073). There were no significant differences in the prevalence of primary angle-closure glaucoma (PACG) and primary open angle glaucoma (POAG) between different genders ( χ2=0.042, P=0.837; χ2=2.838, P=0.092). The prevalence of glaucoma in people over 70 years old was 2.5%, significantly higher than that in other age groups.In patients with glaucoma, the rate of visual impairment was 68.57%(48/70), and the rate of blindness was 47.14%(33/70). There was no significant difference in the incidence of low vision between different types of glaucoma ( χ2=2.785, P=0.248), but there was a significant difference in the rate of blindness ( χ2=10.668, P=0.005). The highest rate of blindness was found in secondary glaucoma.The detection rate of intraocular pressure, anterior chamber depth and C/D was statistically significant ( χ2=43.325, P<0.001), and the positive rate of C/D was the highest.When the factors of intraocular pressure, and C/D were considered jointly, the detection rate of glaucoma could be increased to 55.88%. Conclusions:The prevalence of glaucoma is 1.72% among people over 40 years old in rural areas of Chongqing, the prevalence of PACG is lower than previously recorded, but the proportion of glaucoma-induced visual impairment is higher.In field screening, the morphological examination of the fundus optic nerve is very important for the diagnosis of glaucoma.
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Objective To compare the clinical efficacy and safety following the topical application of pazufloxacin mesylate eye drops with levofloxacin eye drops (LOFX) for bacterial conjunctivitis.Methods A multicenter,randomized,investigator-masked,parallel-controlled clinical trial was performed.Five hundred and twenty eyes of 520 patients with bacterial conjunctivitis were enrolled from March to October 2008 in seven ophthalmic centers in China.The patients were randomized into trial group and control group in 3 ∶ 1 ratio with the 390 eyes in the trial group and 130 eyes in the control group.Pazufloxacin mesylate eye drops was topically used 4 times per day for consecutively 7-14 days in the trial group,and levofloxacin eye drops was used in the same way in the control group.Microbiological cultures for conjunctiva sac secretions and drug sensitive test were carried out before and at the end of the administration of eye drops.The signs and symptoms were observed and scored before treatment and 0,3,7 and 14days after treatment.The adverse events following the administration of the eye drops were evaluated and compared.Results The intention to treat analysis (ITT) showed that the cure rate was 59.38％ in the trial group and 60.47％ in the control group,with the effective rate 88.80％ and 86.05％,respectively,with an insignificant difference between the two groups (x2 =0.12,P =0.72).The clinically evaluable analysis (CE) exhibited that the cure rates were 63.48％ in the trial group and 63.87％ in the control group,with the effective rate 92.46％ and 88.24％,whichwas not significantly different between them (x2 =0.54,P=0.46).The modified-ITT analysis (mITT) showed that the cure rates were 60.57％ in the trial group and 62.07％ in the control group,with the effective rate 90.32％ and 88.51％,without significant difference between the two groups (P＞0.05).Based on microbiologically evaluable analysis (ME),the clinical cure rates were 63.71％ and 63.41％ in the trial group and control group,and the effective rates were 93.44％ and 90.24％,respectively.There was no significantly difference between the both groups (P＞0.05).In the trial group and control group,the bacterial eradication rate was 89.42％ and 90.80％ based on ITT,90.11％ and 92.77％ based on CE,respectively.There was no significant difference in incidences of adverse events following the administration of the drug between the trial group and control group,including ocular tolerance,burning sensation,pricking and itching (P =0.34).Conclusions The effectiveness and adverse response were resemble between Pazufloxacin mesylate eye drops and LOFV following the topical application for bacterial conjunctivitis,which indicate that Pazufloxacin mesylate eye drops is effective and safe.
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Objective To investigate the safety of autologous bone marrow mesenchymal stem cells (ABMSCs) transplantation into the subretinal space for the treatment of proliferative diabetic retinopathy (PDR). Methods The clinical data of four PDR patients ( four eyes ) who received ABMSCs transplantation into the subretinal space were collected in Army Medical University,Southwest Eye Hospital from March 2014 to December 2015,including 3 males and 1 female;the average age was 55 years old;the average course of diabetes was 10 years, and the blood glucoses were all well controlled before treatment. All the patients underwent conventional ophthalmologic examination,and visual acuity,slit lamp microscope,color fundus photography,fluorescein angiography (FFA) and optical coherence tomography ( OCT) examination were performed at 1 week,1 month,3 months,6 months,9 months and 12 months after surgery. This study protocol was approved by Ethic Committee of Army Medical University,Southwest Eye Hospital (No. 2013-34). Results Four patients diagnosed as PDR were enrolled in this study. All patients were performed ABMSC transplantation,and no one felt discomfort after treatment. FFA and OCT showed that the transplanted cells were present in the subretinal space until 1 month after transplantation. The macular edema of one patient diagnosed as macular edema preoperatively was relived gradually after transplantation,and the effects lasted 3 months after transplantation. The preoperative best corrected visual acuity (BCVA) of the two patients were improved from hand movement and finger counting to 20/20 ( 84 ETDRS) and 20/200 ( 38 ETDRS) after transplantation,respectively,and the visual acuities of the other two eyes were both stable. All patients underwent panretinal photocoagulatio 3 months after transplantation, and the follow-up treatment complied with the routine of post-vitrectomy for DR, no complications occurred during the follow-up period. Conclusions Subretinal transplantation of ABMSCs for PDR is safe. The transplanted cells show local anti-inflammatory effect,and no effect on cell proliferation or circulatory improvement are observed.
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Objective To explore the immune-microenvironment of the retinas at different stages of retinal degeneration in Royal College of Surgeon (RCS) rats. Methods RCS-rdy--P+(RCS) rats at early stage (P20), middle stage (P40) and late stage (P60) were involved,12 rats at each post-natal day,RCS-rdy+-P+rats severed as control. Relative concentrations of rat cytokines in rat retina homogenate were detected by using Bio-Plex Suspension Array System. Relative expressions of interleukin-2 (IL-2),C-C motif ligand 2 (CCL2),chemokine (C-X-C motif) ligand 9 (CXCL9),CXCL10,CXCL11 and interferon-γ(IFN-γ) mRNA in rat retina were analyzed by real-time PCR. Expressions of IFN-γ and immune cells surface marker CD4,CD8 and CD161 in the retinas were detected by immunohistochemical staining. Percentage of IFN-γ positive T lymphocytes and natural killer(NK) cells in rat retina were analyzed by flow cytometry. The concentrations of IFN-γ in rat retina homogenate were evaluated by enzyme-linked immunosorbent assay ( ELISA ). The use and care of the animals complied with Regulations for the Administration of Affair Concerning Experimental Animals by State Science and Technology Commission. Results Lymphocytes related cytokines and chemokines mRNA expression levels in the RCS rat retinas showed increase trends with the extension of time. The expression levels of IL-2,CCL2,CXCL9,CXCL10,CXCL11 and IFN-γ mRNA in P60 RCS rat retinas were significantly increased than those in the P20 RCS rat retinas and the control rat retinas (all at P<0.05).The positive rates of CD4,CD8 and CD161 cells in the retinas of P60 RCS rats was (9.09±0.89)%, (18.77±0.38)% and (9.41±0.38)% ,respectively. The proportion of IFN-γ positive cells in the retinas of P60 RCS rats was (8.29±0.27)%,which was significantly higher than that of the control rats ([0.28±0.02]%),with a significant difference between them (t=29.03,P=0.00). CD4+,CD8+and CD161+lymphocytes were mainly distributed in the retinas of P60 RCS rats, and the expressions of IFN-γ were co-located with lymphocyte surface markers. There were significant differences in the concentrations of IFN-γ in the retinas of RCS rats and control rats at different day ages (Fgroup=16.49,P<0.01; Ftime=21.05,P<0.01),the concentration of IFN-γ in retinas of P60 RCS rats was significantly higher than that of P20 RCS rats, P40 RCS rats and control rats, and the differences were statistically significant ( all at P<0.05). Conclusions Along with the process of retinal degeneration,immune privilege balance in the retinas is disrupted, the expressions of lymphocytes related chemokines and cytokines are elevated. Lymphocytes infiltration and activation are appeared in the retina highly activated at the late stage of RP, leading to the significant up-regulation of inflammatory cytokine IFN-γ in microenvironment, which indicates that lymphocytes mediated immune response may take part in retinal degeneration.
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Retinal degeneration is an incurable and irreversible blinding disease caused by the retinal neural cell death. An effective and safe strategy to substitute these injured cells is necessary for retinal recovery. Neural stem cells (NSCs) can differentiate into neural and glial cells. While Müller cells,the main endogenous NSCs in retina, have the features to reentry into the cell cycle and differentiate into neural cells after retinal damage. Although it is highly effective for retinal Müller cell differentiation spontaneously after retinal injury in vertebrates,this feature is rigorously restricted in mammals. Recently,some transcription factors,such as Ascl1,sox2,lin28 and atoh7,can drive quiescent Müller cells back into proliferation to generate new retinal neurons. Moreover,combining Ascl1 expression with a histone deacetylase inhibitor can bypass the limitation and increase the generation of new neurons in adult retina. These regenerated neurons integrate the existing neuronal network and are able to respond to light,indicating that they can likely be used to restore vision. In addition,transplantation of exogenous stem cells can induce Müller cell reprogramming. While these results are extremely promising, the regenerative response is still limited, likely because the proliferative capacity of mammalian Müller cells is low in comparison to their zebrafish counterparts. There may be some kinds of unclear reverse mechanism that suppresses the reprogramming of Müller cells. It is indeed necessary to identify new factors increasing the efficiency of regenerative response.
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Background Normal ultrastructure is the anatomical basis of retinal pigment epithelial(RPE) cells to perform normal physiological function.At present the precipitation method is often used to detect the ultrastructure of RPE cells with transmission electron microscopy(TEM).Objective The aim of this study was to explore a simple and feasible approach to examine the ultrastructure of human embryonic stem cell-derived retinal pigment epithelial (hESC-RPE) cells.Methods hESCs were induced and differentiated into RPE cells by the spontaneous differentiation method,and the expressions of microphthalmia associated transcription factor MITF and paired-box gene 6 (PAX6),specific protein of RPE cells,in the cells were detected by immunofluorescence assay.hESC-RPE cells were inoculated into Transwell filter,and the ultrastructure of the cell sheet was examined under the TEM.Then the ultrastructure of the cell sheet specimens was compared with those of hESC-RPE cells from cell precipitation and RPE cell specimens of 90-day-old Long Evans rats.Results MITF and PAX6 were positively expressed in hESC-RPE cells.The normal ultrastructure were visible in the RPE cells of rats under the TEM,including apical microvilli,polarized melanin granules,cellular nucleus,basement membrane and intercellular junctions,and the ultrastructure of hESC-RPE cell sheet on Transwell was similar to the RPE cells in rats.However,only scatter melanin granules,nonpolar nucleus and scanty microvilli were observed under the TEM in the hESC-RPE cells by cell precipitation method.Conclusions Without digestion process,hESC-RPE cell sheet on Transwell can retain the normal ultrastructure of hESC-RPE cells under the TEM,with a more simple and reliable advantage.
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Objective To observe the clinical efficacy of bevacizumab intravitreal injection combined with laser photocoagulation for di-abetic retinopathy macular edema(DME). Methods 25 DME patients (15 patients, 24 eyes in control group and 10 patients,13 eyes in treatment group) were selected from January 2013 to November 2014 in our hospital. The control group received single Krypton laser (510 nm red and 483 nm yellow) grid photocoagulation or big“C” photocoagulation, while the treatment group received bevacizumab intrav-itreal injection after Krypton laser photocoagulation. The visual acuity were checked, and the macular retinal thickness was detected by opti-cal coherence tomography ( OCT) . Results The difference in preoperative visual acuity between the two groups was not statistically signifi-cant (P>0. 05). All visual acuity improved significantly (P0. 05). And the macular retinal thickness were respectively ( 253. 41 ± 39. 12 )μm and ( 358. 81 ± 43. 24 )μm after treatment, which were all decreased than before (P<0. 05). The macular retinal thickness of the treatment group was better than that of the treatment group after treatment (P<0. 05). Conclusion Single Krypton laser photocoagulation and bevacizumab intravitreal injection combined with Krypton laser photocoagulation are all effective for DME. But treatment combined with Krypton laser photocoagulation could get significantly better postoperative visual acuity re-covery and significantly faster absorption of macular edema.
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Objective To observe safety of intravitreal injection of mouse nerve growth factor and its distribution in retina in rabbits .Methods The behavioral observation ,slit lamp examination ,fundus examination ,eye B ultrasonic and histopathological ex‐amination were carried out on 1 ,7 and 30 d after intravitreal injection 30 μg/100 μL mNGF to determine the safety in eye .The dis‐tribution and peak time in retina were investigated at 15 ,30 min ,1 ,3 ,6 ,8 ,12 ,24 ,48 h after intravitreal injection 125 I‐NGF 30 μg/100 μL .Results No abnormal changes were found in their cornea ,lens ,vitreous body and retina after mNGF intravitreal injection . And the each layer of retinal cells layout were regular according to the result of morphological observation on 30 days after treat‐ment .The peak concentration of mNGF in retina and the highest in whole eye was (118 .32 ± 18 .74)% ID/g and the peak time was at 3 hour after injection .Conclusion It is safe for intravitreal injection of mNGF and mNGF could gather in retina quickly after in‐travitreal injection .
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Stem cells are a group of undifferentiated cells with indefinite self-renewal and pluripotent differentiation ability.They are able to differentiate into precursor/progenitor cells and a variety of cell types and further regenerate new cells to be involved in the repair and rebuilding of injured tissue.Therefore,stem cells are becoming the major research objects in the study on tissue engineering therapy and regenerative medicine.As a sense organ composed of several kinds of neurons and other cells,eyes possesse the dominant superiority in stem cell transplantation therapy because of its good operation controllability and visuality,less demand for seed cells and low rejection after transplantation.These advantages have aroused growing interesting of the fundamental research and clinical trail in stem cell transplantation for irreversible eye diseases.Some exciting advances in the field of stem cell fundamental research,several phase Ⅰ/Ⅱ clinical trials are in progress.The patients with degenerative eye diseases for phase Ⅰ clinical trials are in recruiting in China to evaluate future curative effect and security of stem cell-based therapies.Currently,several issues in stem cell-based eye disease therapies are still pending.We discuss the updated development of stem cell-based transplantation in ophthalmology and future researching direction in order to help ophthalmological researchers to understand the concepts and research strategies.
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Background Researches showed that stem cells can rescue damaged cells through mitochondrial transfer.This mode has been used to regenerative cell-based therapy.Retinal pigment degeneration is an eye disease of retinal pigment epithelial (RPE) cell apoptosis as pathogenetic mechanism.Whether stem cells can repair the target cells by above mechanism has not been clarified.Objective This study was to investigate the influence of mitochondrial transfer on the function of RPE cells.Methods The RPE cells of Long-Evans rats were isolated and cultured and the third generation of cells were used in sequential experiment.The cells were identified by detecting the expressions of RPE65 and Bestrophin proteins with immunofluorescence stain.Mouse neural stem cells (NSCs) (C17.2 strain) with green fluorescence protein (GFP) and without GFP were cultured.Mitotracker-green and Mitotracker-red staining were separately used to labeled the mitochondria of RPE cells and NSCs.RPE cells were cocultured with NSCs,and wheat germ agglutinin (WGA) was used to mark the tunneling nanotubes (TNT) between the two kinds of cells,and then the mitochondrial migration in TNT was exhibited by the laser scanning confocal microscope.The proportion of RPE cells in different cycles was assayed after marked with propidium iodide (PI) by flow cytometry.The contents of ATP,ADP and AMP in RPE cells were detected by high performance liquid chromatography (HPLC).Results The third-generation of RPE cells grew well with the RPE65-and Bestrophinpositive rate ＞85％.The Mitotracker-red-labeled rates of NSCs and RPE cells were no less than 95％.TNT structure was seen to appear the blue fluorescence between RPE cells and NSCs 24 hours after co-cultured and the red dye mitochondria from NSCs migrated toward red dye mitochondria from RPEs with the lapse of time.The RPE cell proportion reduced in G1 phase and increased by 5％ and 2％ in the S phase and G2/M phase respectively after mitochondrial transfer than before (P=0.016,0.114,0.189).The contents of ATP,ADP and AMP in the RPE cells were (8.77 ±3.68),(2.76±0.92) and (1.07 ±0.65) μg/mg after cell co-culture,and those before co-culture were (11.29±2.29),(3.12±0.95) and (1.59± 1.22) μg/mg,without significant differences between them (P =0.370,0.668,0.553).Conclusions NSCs can transfer normal mitochondria to co-cultured RPEs via TNT structure.Mitochondrial exchange might be one of therapeutic mechanisms of NSCs recuing damaged RPE cells.
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<p><b>BACKGROUND</b>Lowering intraocular pressure (IOP) is currently the only therapeutic approach in primary open-angle glaucoma. and the fixed-combination medications are needed to achieve sufficiently low target IOP. A multicenter prospective study in the Chinese population was needed to confirm the safety and efficacy of Bimatoprost/Timolol Fixed Combination Eye Drop in China. In this study, we evaluated the safety and efficacy of Bimatoprost/Timolol Fixed Combination with concurrent administration of its components in Chinese patients with open-angle glaucoma or ocular hypertension.</p><p><b>METHODS</b>In this multicenter, randomized, double-masked, parallel controlled study, patients with open-angle glaucoma or ocular hypertension who were insufficiently responsive to monotherapy with either topical β-blockers or prostaglandin analogues were randomized to one of two active treatment groups in a 1:1 ratio at 11 Chinese ophthalmic departments. Bimatoprost/timolol fixed combination treatment was a fixed combination of 0.03% bimatoprost and 0.5% timolol (followed by vehicle for masking) once daily at 19:00 P.M. and concurrent treatment was 0.03% bimatoprost followed by 0.5% timolol once daily at 19:00 P.M. The primary efficacy variable was change from baseline in mean diurnal intraocular pressure (IOP) at week 4 visit in the intent-to-treat (ITT) population. Primary analysis evaluated the non-inferiority of bimatoprost/ timolol fixed combination to concurrent with respect to the primary variable using a confidence interval (CI) approach. Bimatoprost/timolol fixed combination was to be considered non-inferior to concurrent if the upper limit of the 95% CI for the between-treatment (bimatoprost/timolol fixed combination minus concurrent) difference was ≤ 1.5 mmHg. Adverse events were collected and slit-lamp examinations were performed to assess safety. Between-group comparisons of the incidence of adverse events were performed using the Pearson chi-square test or Fisher's exact test.</p><p><b>RESULTS</b>Of the enrolled 235 patients, 121 patients were randomized to receive bimatoprost/timolol fixed combination and, 114 patients were randomized to receive concurrent treatment. At baseline the mean value of mean diurnal IOP was (25.20 ± 3.06) mmHg in the bimatoprost/timolol fixed combination group and (24.87 ± 3.88) mmHg in the concurrent group. The difference between the treatment groups was not statistically significant. The mean change from baseline in mean diurnal IOP (± standard deviation) in the bimatoprost/timolol fixed combination group was (-9.38 ± 4.66) mmHg and it was (-8.93 ± 4.25) mmHg in the concurrent group (P < 0.01). The difference between the two treatment groups (bimatoprost/timolol fixed combination minus concurrent) in the change from baseline of mean diurnal IOP was -0.556 mmHg (95% CI: -1.68, 0.57, P = 0.330). The upper limit of the 95% CI was less than 1.5 mmHg, the predefined margin of non-inferiority. Adverse events occurred in 26.4% (32/121) of the bimatoprost/timolol fixed combination patients and 30.7% (35/114) of the concurrent patients. The most frequent adverse event was conjunctival hyperemia, which was reported as treatment related in 16.5% (20/121) in the bimatoprost/timolol fixed combination group and 18.4% (21/114) in the concurrent group (P > 0.05).</p><p><b>CONCLUSIONS</b>Bimatoprost/Timolol Fixed Combination administered in Chinese patients with open-angle glaucoma or ocular hypertension was not inferior to concurrent dosing with the individual components. Safety profiles were similar between the treatment groups.</p>
Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Amides , Therapeutic Uses , Bimatoprost , Cloprostenol , Therapeutic Uses , Glaucoma, Open-Angle , Drug Therapy , Ocular Hypertension , Drug Therapy , Timolol , Therapeutic UsesABSTRACT
<p><b>OBJECTIVE</b>A systematic review of literature was performed to compare various visual function parameters including the final visual acuity outcome and/or adverse events between corneal refractive surgery (CLRS) and phakic intraocular lens implantation (p-IOLi) in the treatment of refractive amblyopic children.</p><p><b>DATA SOURCES</b>Two reviewers independently searched the PubMed, EMBASE, and Controlled Trials Register databases for publications from 1991 to 2013.</p><p><b>STUDY SELECTION</b>There were 25 articles, including 597 patients and 682 eyes, was included in CLRS group. Among them, 21 articles reported the use of CLRS in the treatment of myopic anisometropia for 318 patients (13 photorefractive keratectomy or laser epithelial keratomileusis and eight laser in situ keratomileusis). And 11 articles had the results of CLRS in treating hyperopic anisometropic amblyopia children. Eleven articles reported the effect of p-IOLi for treating high myopia or anisometropic amblyopia, including 61 patients (75 eyes). Age, pre- and postoperation best-corrected vision acuity (BCVA), and spherical equivalent (SE) were compared in CLRS and p-IOLi groups.</p><p><b>RESULTS</b>The average age of CLRS group and p-IOLi group has no statistically significant difference. The SE in CLRS group for myopic anisometropia amblyopia patients was (-10.13 ± 2.73) diopters (D) and for hyperopic anisometropia amblyopia patients was (5.58 ± 1.28) D. In p-IOLi group the SE was (-14.01 ± 1.93) D. BCVA was improved significantly in both groups, and even better in p-IOLi group. Refractive errors were corrected in both groups, but there was no clinically significant difference in final SE between each group. More than one-half of the children had improved binocular fusion and stereopsis function in both groups.</p><p><b>CONCLUSIONS</b>Both CLRS group and p-IOLi group showed their advantage in treating refractive amblyopia in children. In comparing p-IOLi with CLRS for treatment of refractive amblyopia, no statistically significant difference in final BCVA was observed.</p>
Subject(s)
Child , Child, Preschool , Humans , Amblyopia , General Surgery , Therapeutics , Anisometropia , MyopiaABSTRACT
<p><b>OBJECTIVE</b>To assess the effect of preformed orbital titanium mesh in the reconstruction of orbital fracture.</p><p><b>METHOD</b>Twenty-seven cases of blow-out orbital fracture were diagnosed in the period from January 2012 to July 2012, all with serious defect of the orbital wall and herniation of the orbital soft tissues. Preformed orbital titanium mesh was grafted to the traumatic orbital walls. Orbital axial and coronal CT and three-dimension CT scan examination were performed routinely in all cases preoperatively and postoperatively to evaluate the postoperative exophthalmos and orbital wall reconstruction.</p><p><b>RESULTS</b>All the patients were followed up for 3 months. Orbital wall reconstruction was successfully performed in all cases without serious complications. The postoperative enophthalmos was less than 3 mm in 23 of the 27 cases.</p><p><b>CONCLUSION</b>Preformed orbital titanium mesh allows accurate reconstruction of orbital wall fracture.</p>
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Adolescent , Adult , Aged , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Young Adult , Orbital Fractures , General Surgery , Prosthesis Design , Plastic Surgery Procedures , Methods , Surgical Mesh , TitaniumABSTRACT
Objective To observe the mutifocal electroretinogram (mfERG) characteristics of rod and cone cells in patients with retinitis pigmentosa (RP) and to evaluate the function of photosensory cell.Methods The mfERG recording technique for rod cell in eight normal subjects (eight eyes) were established and the influence of different brightness lightstimulus in P1 wave amplitude were analyzed.The cone and rod cells mfERG of 38 eyes in 19 patients were recorded and then calculated positive ratio from local signal-noise ratio.The average visual acuity and P1 wave amplitude density of cone mtERG in different types were compared and statistically analyzed.Meanwhile,the changes in P1 wave amplitude of cone and rod mfERG in four quadrants also compared and analyzed.Results Rod cell mfERG in normal subjects can be recorded stably by using blue flashes with low light intensity as 0.04 cd/m~2.In patients with RP,the cone and rod cells mfERG can he detectd 65.790./00 and 10.51% respectively.P1 wave amplitude density in type I of cone cell mfERG was significantly higher than that in type Ⅱ (t=5.21,P=0.000).There were no differences in average visual acuity (t=1.15,P=0.612).P1 wave amplitude density in type Ⅰ was negatively related to IogMAR visual acuity (r=-0.48,P=0.04 ).The comparison of rod and cone cells mfERG in local wave characteristics showed that P_1 wave amplitude densities had spatial relationship in each area.Conclusions The results suggested highly variable central responses in cone cell in RP patients,higher positive recorded ratio in cone cell than rod cell and spatial correspondence between the function of reserved cone and rod cells.
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Objective To observe the distribution and concentration of ~(125)I-nerve growth factor (NG-F) in rabbits' eyes after intravitreal injection and posterior juxtascleral injection.Methods Intravitreal injection(group A) and posterior juxtascleral injection (group B) were performed with the dosage of 30μg/100μl ~(125)I-NGF on left and right eyes in 45 white rabbits respectively.The γ-counts and the concentration of ~(125)I-NGF (%ID/g) of each ocular tissue was determined 15 and 30 minutes,and 1,3,6,12,24,and 48hours after injection.Results The ~(125)I-NGF diffusion in group A was faster in ocular content and ocular inner wall.The vitreous content of ~(125)I-NGF decreased gradually in group A,the curve changes in other eye tissues were normal.The concentration of ~(125)I-NGF reached the peak 3 hours after injection in aqueous humor,iris and ciliary body,retina,and choroids,but 6 hours after injection in sclera and 8 hours in cornea.The changes of concentration of ~(125)I-NGF in group B showed normal curve change.The peak time in group B were all 6 hours,in all the tissues except aqueous humor (3 hours).Except the high concentration in vitreous body caused by intravitreal injection,the concentration of ~(125)I-NGF in retina was the highest in group A.Conclusion Intravitreal injection of ~(125)I-NGF can gain higher concentration in each ocular tissue than posterior juxtaseleral injection,especially in retina.So intravitreal injection of NGF is a better ocular delivery method to treat the ocular fundus diseases.
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Objective To explore the electrophysiological properties and the disparity of visual cortical neurons in developing rats. Methods Whole cell patch clamp recording and intracellular labeling of brain slices were performed on rats at postnatal 14 and 28 days. The electrophysiological data were analyzed according to the cellular input resistance and resting membrane potential. Results When the input impedance of visual cortical neurons(IR) was lower, increased peak value of postsynaptic currents(PSCs), prolonged rise and decay time were found. At postnatal 14th day(before eyes opened), the intermediate cells and mature cells were 59.2% and 14.9% respectively, but at postnatal 28th day(14 days after eyes opened), the mature cells and immature cells were 62.5% and 12.5% respectively. Conclusion During the period of postnatal development, the visual cortical neurons become mature gradually, but maturation is not completely correlated with age.
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Objective To investigate the electrophysiological properties of neurons in visual cortex of binocular form-deprivated rats during the developmental stages and to explore the synaptic and cellular mechanisms of plasticity in the visual cortex. Methods Whole cell patch clamp technique was applied to the visual cortex slices prepared from 61 Wistar rats of both genders, which were divided into two groups; control group and binocular form-deprivation (BFD) group. Excitatory postsynaptic currents (EPSCs) and long term potentiation (LTP) of the neurons were recorded. Results (1) The percentage of silent response in BFD group was significantly higher than that in the control group(P
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Objective To investigate the electrophysiological properties of retinal ganglion cells(RGCs) in Long Evans rats during different postnatal developmental stages so as to explore the intracellular mechanism of retinal neuron maturation. Methods Whole cell patch clamp recordings of RGCs in acute retinal slices of Long Evans rats (postnatal days 3 to 31) were performed. Depolarizing current pulses of different densities were inflicted on RGCs to evoke action potentials(AP) . Results A total of 94 RGCs, single spike cells, transient and sustained cells, were acquired in 33 rats. The proportion of the three types of TGCs was different. There was significant difference in electrophysiological properties. Conclusion During the period of postnatal development, gradually matured electrophysiological properties of RGCs and differences in amplitudes and frequencies of AP suggest that different types of RGCs may play different roles in coding and transmitting spatial and temporal information.
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0.05) , but significant difference in latency time of N145 was found between the three groups (P
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Objective To study the membrane properties of rat retinal ganglion cells during postnatal development, including the passive membrane properties and the action potentials evoked by depolarizing current injections and the relationship between the membrane properties and ages. Methods Whole cell patch clamp recordings of the retinal ganglion cells (RGCs) in retinal slices of postnatal rats (age ranging from postnatal days 7 to 30) were performed. Results (1) A total of 112 RGCs were recorded from postnatal rats. (2) The electrophysiological properties of RGCs changed significantly during development. The excitability of RGCs increased in an age-dependent manner. There was significant difference between before-eye-opening group(P7-13d) and after-eye-opening group(P14-30d) . (3) Three different discharge patterns of RGCs in response to sustained depolarizing current pulses were recorded: single-spike firing, transient firing and sustained firing. During development, retinal ganglion cells of rats exhibited pronounced changes in the discharge patterns(P