1.The distribution of nerve growth factor in rabbits' eyes after intraocular injection in two different means
Chinese Journal of Ocular Fundus Diseases 2009;25(6):470-473
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.
2.Safety of intravitreal injection of nerve growth factor and its distribution in retina
Danning LIU ; Jishan FAN ; Zhengqin YIN
Chongqing Medicine 2015;(3):289-292
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 .
3.Electrophysiological and morphological features of retinal ganglion cells in rats
Zonghua WANG ; Zhengqin YIN ; Shijun WANG
Chinese Journal of Ocular Fundus Diseases 2001;0(03):-
Objective To observe the electrophysiological and morphological features of retinal ganglion cells (RGCs) in rats, and investigate its effect on the visual signal conduction. Methods Whole cell recordings were obtained from 112 RGCs of 30 rats at the age of 7-30 days. Resting membrane potential (RMP) was recorded, and input impedance was noted after given 2 mV hyperpolarizing current by voltage clamp. The action potential (AP) was induced by deplorizing current at different densities. The histological staining was actualized by injecting with biotin into the RGCs, and the diameter of the cells was measured. Results Three different discharge patterns of RGCs in response to maintained depolarizing currents were recorded: single spike (25 RGCs), transient firing (40 RGCs), and sustained firing (47 RGCs). The diameter was 14-16 ?m in 57.14% transient firing RGCs, and 10-12 ?m in 62.50% sustained firing RGCs. The maximum frequency of AP of sustained firing RGCs was significantly higher than that of transient firing RGCs (P
4.Noggin induces human bone marrow-derived mesenchymal stem cells to differentiate into neural cells
Yuxiang TAO ; Haiwei XU ; Zhengqin YIN
Journal of Third Military Medical University 2003;0(09):-
Objective To study whether noggin alone can induce human bone marrow mesenchymal stem cells (MSCs) to differentiate into neural cells for the treatment of neural degenerative diseases.Methods Human bone marrow MSCs were primarily cultured and then divided into control,Ad group of empty adenovirus vector and Ad-noggin group of adenovirus vector with noggin gene.Their morphological changes were observed with fluorescence microscopy and laser confocal microscopy,and the results of 48 h,4,7,10 d were analyzed with statistical methods.Results Both the vector made human bone marrow MSCs carry green fluorescence.Ad group didn’t show any morphological changes.While for Ad-noggin group,a few neural-like cells appeared in 48 h after transfection.The number of such cells was increased,and there were some neurites around the cells after 4 d.The cells amplified greatly after 10 d.Compared to those of 7 d after transfection,the soma and dendritic diameters of Ad-noggin group were significantly increased after 10 d (P
5.Improvement of RPE cells growth and metabolism abilities by mitochondrial transfer of neural stem cells
Rongsha, SUN ; Haiwei, XU ; Zhengqin, YIN
Chinese Journal of Experimental Ophthalmology 2015;33(5):424-429
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.
6.The current study, challenges and application of stem cell transplantation in ophthalmology
Zhengqin, YIN ; Shiying, LI ; Qian, JIAN
Chinese Journal of Experimental Ophthalmology 2015;33(9):769-773
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.
7.Multifocal electroretinogram of rod and cone cells in patients with retinitis pigmentosa
Yong LIU ; Yanji YU ; Zhengqin YIN
Chinese Journal of Ocular Fundus Diseases 2009;25(6):433-436
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.
8.Bevacizumab intravitreal injection with photocoagulation for diabetic retinopathy macular edema
Ling LIU ; Yong LIU ; Zhengqin YIN
Journal of Regional Anatomy and Operative Surgery 2015;(3):260-262,263
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 (P<0. 05) after treatment and the treatment group got a better result compared to the control group(P <0. 05). The preoperative macular retinal thickness in treatment and control groups were respectively (510. 75 ± 61. 06)μm and(487. 47 ± 43. 41)μm, and the difference between them was not statistically significant (P>0. 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.
9.The relationship between electrophysiological and morphological properties of neurons in visual cortex of developing rat-intracellular staining study
Yali TU ; Zhengqin YIN ; Yingbing LIU
Chinese Journal of Ocular Fundus Diseases 2000;0(04):-
Objective To investigate the relationship between electrophysiological and morphological properties of neurons in visual cortex of developing rat, speculate the coincided degree between electrophysiological and morphological change and realize the mechanism of normal visual development. Methods Whole cell patch-clamp recording and intracellular staining were used to acquire cellular microelectrode recording in visual cortex from Sprague-Dawley rats (4~28 days old). The histological process was made. Results The differences of electrical feature between pyramidal cells and non-pyramidal cells were significant. The morphological maturity degree is different in developing visual cortex. Conclusion The different function of pyramidal and non- pyramidal cells in local integrition is reflected by their electrical feature in the process of visual development. In critical period of visual development, the coincision degree of the electrophysiological and morphological change in visual cortex is larger than that in the subcortex constructure.
10.Effects of human vitreous fluid on the proliferation of cultured human retinal pigment epithelial cells and vascular endothelial cells
Yong LIU ; Yi WANG ; Zhengqin YIN
Chinese Journal of Ocular Fundus Diseases 1999;0(02):-
Purpose To investigate the effects of human vitreous fluid on proliferation of cultured human retinal pigment epithelial (RPE) cells and vascular endothelial cell lines(VEC304). Methods Human RPE cells and VEC304 were cultured and treated in different human vitreous conditioned medium (VCM) with or without serum, vitreous volume concentrations of VCM were 1∶8, 1∶4 and 1∶2. Cells proliferation was assayed by tetrazolium (MTT) colorimetry at the 2nd, 4th and 6th day respectively. Results In the presence of serum, 1∶4, 1∶2 VCM had a significantly stimulative effect on RPE cells proliferation compared with control group at the 2nd, 4th, and 6th day retrospectively ( P