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Objective To investigate the expression of γ-aminobutyric acid A receptor α1 subunit (GABAAα1) in the ventrolateral periaqueductal gray (vLPAG) in rats with formalin-induced acute pain. Methods The rats were randomly divided into two groups:control group(group C) and formalin-induced pain group(group F),12 rats in each group:0.9% sodium chloride solution or 2% formaldehyde 50 μL was injected into the ventral surface of right hind paw respectively. The pain scores were recorded for every 5 minutes and the mechanical pain threshold were recorded for every 10 minutes until 1 h. The expression levels of GABAAα1in vLPAG were determined by Western blot analysis in each group.Results The rats in formalin group showed significant nociceptive behaviors immedi-ately, such as paw withdrawal and/or paw licking. Results demonstrated that the rats exhibited a biphasic response to pain. The pain behavior scores in group F were significantly higher than that in group C (P<0.05),and the mechanical pain threshold in group F was decreased after injection compared with group C(P<0.05). The expression of GABAAα1 protein in group F was significantly higher than that in group C (P<0.05).Conclusions The up-regulation of GABAAα1 expression in ventrolateral periaqueductal gray is associated with the decrease of pain threshold in rats with acute pain.
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?AIM:To investigate the correlation between dry eye and different degrees of diabetic retinopathy ( DR ) in type 2 diabetic patients.?METHODS: In the cross-sectional study, 340 patients (340 eyes) with type 2 diabetes were enrolled. Tear film function tests including tear meniscus height, tear film breakup time ( BUT ) , fluorescein staining, Schirmer Ⅰtest were performed followed by surveying questionnaires about dry eye. Retinal status was evaluated by retinal color photography and indirect ophthalmoscopy exam with dilated pupils to evaluate DR and whether companied by macular edema.?RESULTS:The prevalence of dry eye was 49. 41%. The mean duration of diabetes in patients with dry eye was 11.15±7.07a, while 6.92±5.45a without dry eye(P<0.01). Dry eye had the positive correlation to the development of DR. The incidence of dry eye in people with mild nonproliferative diabetic retinopathy ( NPDR ) , moderate NPDR, severe NPDR and proliferative diabetic retinopathy (PDR) was 1. 097 times, 1. 724 times, 2. 86 times and 5. 43 times respectively, compared with people without DR. The occurrence of dry eye in people with macular edema increased by 3. 697 times compared with people without macular edema.?CONCLUSION: Dry eye was more prevalent in people with type 2 diabetes. The incidence of dry eye increased gradually with the occurrence and development of diabetic retinopathy.
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Background Posterior capsular opacification (PCO) following cataract extracapsular extraction is a major cause of the reduction of visual acuity.Topical administration of eye drops is a research hotspot for the prevention of PCO.Objective This study was to evaluate the release of cyclosporine A-loaded chitosan nanoparticles (CyA-CS-NP) by ionic gelation in vitro and its feasibility of modification of the surface of polymethylmethacrylate intraocular lens (PMMA IOL) with CyA-CS-NP.Methods The CS-NP and CyA-CS-NP were prepared by ionic gelation of CS with sodium tripolyphosphate.The characteristics of CS-NP,such as the appearance and mean size,and drug entrapment efficient (EE),loading capacity (LC),and the drug release were studied ; the CyA content on the IOL surface was detected by high performance liquid chromatography (HPLC).The IOL surface modified with CyA-CS-NP was observed by scanning electron microscope and X-ray photoelectron spectroscopy technique (XPS),the changes of elements and chemical bond types between simple plasma processed IOL and CyA-CS-NP modified IOL were analyzed.The transmittance at the wavelength of 360-490 nm and refraction of IOL were detected using back focal length method and spectrophotometer,and the effective resolution of IOL was evaluated according to the instruction of ISO/CD 11979-2.Loops anti fatigue test of IOL referred to the criteria of ISO/CD 11979-3.Results The CS-NP and CyA-CS-NP showed monodisperse,uniform appearance similar to spherical shape with a mean size of (158±18) nm and (219±29) nm,respectively.The CyA-CS-NP had high CyA association efficiency and loading capacity (64.2％ and 7.6％).In vitro release study revealed a fast release on the first day followed by a increased drug release during an 11-day following up.The sustained release was approximately 46.6％ at day 1 and 77.7％ at day 12,respectively.The surface of IOLs with cling film was smooth without CS-NP;while the edge of IOLs appeared a layer of CyA-CS-NP after modification.XPS analysis displayed some elements such as phosphonium,CNH2 and O =CN that appeared on the modified surface,indicating that CyA-CS-NP existed on the surface of IOLs edge.The mean quality of CyA on three IOLs surface after modification was 171.88 μg.The diopter,distinguishing ability and transmittance of modified IOL were (16.64±0.23) D,(90.28 ± 0.25) ％ and (73.57 ±0.62) ％,and those of unmodified IOL were (16.62±0.29) D,(90.28±0.21) ％,(73.61±0.60)％,without significant differences between them (t =0.381,0.078,2.291,all at P ＞ 0.05).The antifatigue ability of loops complied with the criteria of ISO/CD 11979-3.Conclusions The optical property and antifatigue ability of loops of the edge-modified IOLs by CyA-CS-NP reach the normal standard and meet the requirement of clinic application.The edge-modified IOLs by CyA-CS-NP can be a delivery system for intraocular drug release.
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BackgroundPterygia is a clinical common disease.A lot of surgical methods are developed to decrease the recurrence rate.Resent years,the application of fibrin glue is receiving more and more attention.Objective This study was to explore the effects of fibrin glue in decreasing inflammatory irritation and its mechanism. Methods Pterygia models were created in 12 clean rabbits by exsection of limbal tissue and topical administration of 1.25％ diluted hydrochloric acid,and then the conjunctival autograft surgery was performed in the experimental rabbits.The conjunctival flap was sutured in the left eyes,and the conjunctival wound was closed using fibrin glue in the right eyes.The operation duration for each group was documented and compared.The irritation sign was examined under the slit lamp in all the rabbits 1 week and 4 weeks respectively.The expressions of vascular endothelial growth factor (VFGF) and basic fibroblast growth factor (bFGF) proteins in the conjunctiva tissue were detected by immunochemistry,and the expressions of VFGF mRNA and bFGF mRNA in the conjunctival tissue were determined by reverse transcription polymerase chain reaction (RT-PCR).Results The operative duration was (21.3±0.2) minutes in suture group and( 10.1 ±0.1 )minutes in the fibrin glue group with a significant difference between two groups( t =102.242,P＜0.05 ).From 1 week through 4 weeks,the hyperemiain degree was obviously slight in fibrin glue group compared with suture group.Immunochemistry showed that VEGF and bFGF proteins were expressed mainly in the cytoplasm of conjunctival epithelium layer.The positive response intensity was weaker in the fibrin glue group than in suture group 1 week and 4 weeks after operation.RT-PCR revealed that the expression level of VEGF mRNA was significantly lower in fibrin glue group than in suture group,and the VEGF mRNA was gradually decreased with the time lapse ( Fgroup =174.443,P =0.000 ; Ftime =231.459,P =0.000 ).The similar outcomes were found in the expression of bFGF mRNA(Fgroup=41.727,P=0.000;Ftime=55.417,P=0.000). ConclusionsThe use of fibringluecanshortentheoperationdurationandreducepostoperationinflammatoryreaction.The downregulation of VEGF and bFGF in tissue is the possible mechanism of remitting irritation sign,which allows a reduce of the recurrence rate of pterygia.