Balanced Salt Solution Group Research Articles

Flow characterization and structural alterations in Ahmed glaucoma FP7 tubes after in-vitro aging in silicone oil.

Patients with intraocular silicone oil (SO) display higher odds of surgical failure after Ahmed glaucoma valve (AGV) implantation compared to patients without SO. However, the structural impact of SO exposure on silicone-made AGV tubes and the resulting changes in flow rate remain unexplored. This in-vitro study evaluated changes in tube dimensions and flow rates of AGV FP7 tubes after SO exposure to inform clinicians how such changes may impact AGV functionality. AGV FP7 tube segments underwent accelerated aging to approximate 90 days of exposure to the following media: Balanced Salt Solution (BSS), 1000 centistokes (cs) SO, and 5000cs SO. Tube dimensions were measured before and after aging. A constant gravity flow test setup was created to measure flow rates through tubes before and after aging. The students' T-test was used to compare the mean change between groups post-aging. Post-exposure, 1000cs and 5000cs SO tube segments increased in length by 5.94% and 5.55%, respectively, compared to 0.38% of BSS tubes (P < 0.05 for both). The inner lumen area expanded for tube segments in 1000cs and 5000cs SO by 11.75% and 2.70%, respectively, but contracted for tubes in BSS by -2.70% (P < 0.01 and P = 0.068 for 1000cs and 5000cs SO, respectively). Post aging, the flow rates increased on average by 61.0% and 98.6% for 1000cs and 5000cs SO, respectively, whereas flow rates for BSS tube segments slightly decreased by -4.92%. The difference was statistically significant for BSS vs. SO groups (P < 0.01 for both). Prolonged exposure to SO structurally altered the AGV FP7 tube segments by expanding their cross-sectional area, potentially leading to increased flow rates. These results may inform clinicians about potential in-vivo interactions in patients with the simultaneous presence of glaucoma drainage devices and intraocular SO.

Efficacy of 2% Hydroxypropyl Methylcellulose and Bandage Contact Lens for the Management of Dry Eye Disease after Cataract Surgery

Objectives. To investigate the effect of 2% hydroxypropyl methylcellulose (HPMC) and bandage contact lens (BCL) on dry eye disease after cataract surgery. Methods. This prospective randomized controlled trial included 63 eyes which were divided into the balanced salt solution (BSS), HPMC, BCL, and combined HPMC and BCL (H&amp;B) groups. The Ocular Surface Disease Index (OSDI), tear meniscus height (TMH), and average tear break-up time were measured before cataract surgery and 30 days postoperatively. Differences in corneal nerve fiber (CNF) and dendritic cell (DC) density in various directions were evaluated and compared. The CNFs and DCs in central and infratemporal directions were observed using in vivo confocal microscopy. Data were evaluated using the Kruskal–Wallis rank-sum test and analysis of variance. Results. The differences in variations in OSDI and TMH after cataract surgery between the four groups were statistically significant (P&lt;0.05). The postoperative OSDI of the HPMC group decreased compared with their preoperative OSDI. A statistically significant difference in the variations of OSDI score was observed between the HPMC and other groups (P&lt;0.05). The postoperative variations in TMH in the HPMC group were significantly higher than those observed preoperatively and significantly differed between HPMC and BCL groups and between BCL and H&amp;B groups (P&lt;0.05). Postoperatively, the density of corneal DCs decreased in BSS and HPMC groups and increased in BCL and H&amp;B groups (P&lt;0.001). Conclusions. The application of 2% HPMC in cataract surgery has a certain effect on managing dry eye after cataract surgery. Although the use of BCLs after cataract surgery has some benefits, it may cause mild ocular surface inflammation. Nevertheless, using 2% HPMC with BCLs in the perioperative phase of cataract surgery can alleviate the subjective discomfort of patients and can safely and effectively replace eye patch after cataract surgery.

A pilot study of viscoelastic agent to prevent recurrent vitreous hemorrhage after vitrectomy for proliferative diabetic retinopathy

BackgroundTo evaluate the possibilty of preventing recurrent vitreous hemorrhage (RVH) after vitrectomy in proliferative diabetic retinopathy (PDR) patients with unabsorbed vitreous hemorrhage (VH) by intravitreal injection of viscoelastic agent (VA) at the end of the surgery and compared its effect with triamcinolone acetonide (TA).MethodsThis was a pilot prospective, observational study. PDR patients with VH who underwent vitrectomy were assigned to 3 groups according to the tamponade applicated at the end of the surgery, including VA group (intravitreally injected 1 ml VA if the retina was prone to bleed during the operation), TA group (intravitreally injected 2 mg TA when there was much exudates), or balanced salt solution (BSS) group (no tamponade). Then postoperative follow-up was performed routinely until 6 months after surgery. The primary outcome was the incidence of RVH, secondary outcome were the best-corrected visual acuity (BCVA) and introcular pressure (IOP). Cataract formation and other complication were also assessed.ResultsA total of 68 eyes, from 68 patients, were included. 18,18,32 eyes were enrolled in the VA group, TA group and BSS group, respectively. The integral incidence of RVH after vitrectomy was 5.6%, 5.6% and 12.5% respectively (P = 0.602). There was no early RVH in VA or TA group, whereas 3 early RVHs were identified in BSS group, however there was no significant difference (P = 0.171). Every group had one late RVH case. In all groups, final BCVA showed significant improvement compared to baseline. BCVA at any postoperative visit showed no significant differences among 3 groups. Mean IOP was higher 1 week after surgery in VA group compared with the other groups; however, in other times the differences were not significant. No cataract formation and other complication was noted in 3 groups.ConclusionIntravitreal injection of VA or TA at the end of vitrectomy for PDR patients with unabsorbed VH tend to reduce the incidence of early RVH after vitrectomy similarly. As VA was preferred to applicate in the eyes that were prone to bleed, intravitreal injection of VA at the end of vitrectomy might be a promising method for preventing RVH in PDR patients.

The Inhibitory Effect of Connective Tissue Growth Factor Antibody on Postoperative Fibrosis in a Rabbit Model of Trabeculectomy.

To compare the efficacy of subconjunctival injection of an anti-connective tissue growth factor antibody (anti-CTGF) versus mitomycin-C (MMC) and placebo in reducing scar formation in a rabbit model of trabeculectomy. A total of 14 rabbits were included. Nine rabbits underwent trabeculectomy with subconjunctival injections of either anti-CTGF antibody, MMC, or balanced salt solution (BSS), each administered in three eyes, before peritomy. The anti-CTGF group received a repeated dose of the antibody five days after surgery. All nine rabbits were euthanized on day 14; the globes were stained with hematoxylin & eosin, Masson's Trichrome, and immunohistochemistry for detecting alpha-smooth muscle (α-SMA) actin. RNA extraction was performed on five eyes of the remaining rabbits which included one eye without any surgery, one eye 5 hr after trabeculectomy without any injection, one eye five days after trabeculectomy without any injection, and two eyes five days after trabeculectomy with administration of MMC and BSS, respectively. The mean bleb area in the anti-CTGF, MMC, and control groups was 3.8 1.45, 5.9 1.4, and 3.5 1.9 mm2, respectively. Collagenous tissue was found to occupy the bleb area by 13.7%, 13.5%, and 18.5%, respectively. This ratio was significantly higher in the BSS group (P = 0.04). The expression of CTGF mRNA after 5 hr and five days in eyes undergoing trabeculectomy were significantly more pronounced as compared to the unoperated eye. The mean H-SCORE of α-SMA-immune reactive cells calculated as the grade of staining multiplied by the percentage of immune stained cells was 14.6, 10.22, and 140.58 in the anti-CTGF, MMC, and control groups, respectively. While the control eyes had a significantly higher score (Ps 0.001), the anti-CTGF and MMC groups were comparable (P = 0.87). Based on the results of this animal study, the anti-CTGF antibody injection resulted in a significant reduction in collagenous tissue and myofibroblast cells after trabeculectomy.

Comparison of different endophthalmitis prophylactic measures in cataract surgery - An analysis of 2.4 lakh cases.

To compare different endophthalmitis prophylaxis methods adopted in cataract surgery (manual small-incision cataract surgery and phacoemulsification) between the years 2013 and 2021 in the community eye care section of a tertiary eye care hospital in South India and report their outcomes. All cataract surgeries performed from January 2013 to December 2021 (2,46,874 surgeries) at a single center were included in this retrospective study. The different endophthalmitis rates with each regimen were analyzed and evaluated. 70,081 surgeries were performed from January 2013 to February 2015, where Tobramycin was added to Balanced Salt Solution (BSS) (Group A). From March 2015 to January 2017, 63,245 surgeries were performed when intracameral Moxifloxacin was given (Group B). From February 2017 to December 2021, 1,13,548 surgeries were performed were Amikacin was added to BSS (Group C). In total, 42 cases of postoperative endophthalmitis were reported during the study period (0.02%). There was no significant difference in the endophthalmitis rates between groups A and B (P = 0.4152); however, there was a significant decrease in endophthalmitis rates in group C when compared with group A (P = 0.04) and group B (P = 0.006). There was a significant reduction in the rates of endophthalmitis following the addition of amikacin in irrigating BSS. Nocardia was one of the predominant organisms isolated from these endophthalmitis patients. This is the first single-center study to report a comparative analysis of different endophthalmitis prophylactic measures in a community eye care set up with a high incidence of Nocardia endophthalmitis prevented with amikacin in BSS irrigating solution.

Inhibition of experimental autoimmune uveitis by intravitreal AAV-Equine-IL10 gene therapy.

Equine recurrent uveitis (ERU) is a spontaneous, painful, and vision threatening disease affecting up to 25% of equine populations worldwide. Current treatments of ERU are non-specific and have many side effects which limits them to short-term use. In order to develop an effective therapy for ERU, we investigated the use of adeno-associated virus (AAV) gene therapy, exploiting a natural immune tolerance mechanism induced by equine interleukin-10 (Equine-IL10). The purpose of this study was to evaluate the therapeutic efficacy of a single intravitreal (IVT) dose of AAV8-Equine-IL10 gene therapy for inhibition of experimental autoimmune uveitis (EAU) in rats. Each rat was dosed intravitreally (IVT) in both eyes with either balanced salt solution (BSS) (control; n = 4), AAV8-Equine-IL10 at a low dose (2.4x109 vg; n = 5) or high dose (2.4x1010 vg; n = 5). EAU was induced in all groups of rats 7 days after IVT injections and euthanized 21 days post-injection. Ophthalmic examination and aqueous humor (AH) cell counts were recorded with the observer blinded to the treatment groups. Histopathology and qPCR were performed on selected ocular tissues. Data presented herein demonstrate that AAV8-Equine-IL10 treated rats exhibited a significant decrease in clinical inflammatory scores and AH cell counts compared to BSS-treated EAU eyes on days 10, 12 and 14 post EAU induction at both administered vector doses. Mean cellular histologic infiltrative scores were also significantly less in AAV8-Equine-IL10 dosed rats compared to the BSS group. Intravitreal injection of AAV8-Equine-IL10 resulted in Equine-IL10 cDNA expression in the ciliary body, retina, cornea, and optic nerve in a dose-dependent manner. A single IVT injection of AAV8-Equine-IL10 appeared to be well-tolerated and inhibited EAU even at the lowest administered dose. These results demonstrate safety and efficacy of AAV8-Equine-IL10 to prevent EAU and support continued exploration of AAV gene therapy for the treatment of equine and perhaps human recurrent uveitis.

Therapeutic potential of human umbilical cord-derived mesenchymal stem cells transplantation in rats with optic nerve injury.

Purpose:There are no effective treatments currently available for optic nerve transection injuries. Stem cell therapy represents a feasible future treatment option. This study investigated the therapeutic potential of human umbilical cord–derived mesenchymal stem cell (hUC-MSC) transplantation in rats with optic nerve injury.Methods:Sprague–Dawley (SD) rats were divided into three groups: a no-treatment control group (n = 6), balanced salt solution (BSS) treatment group (n = 6), and hUC-MSCs treatment group (n = 6). Visual functions were assessed by flash visual evoked potential (fVEP) at baseline, Week 3, and Week 6 after optic nerve crush injury. Right eyes were enucleated after 6 weeks for histology.Results:The fVEP showed shortened latency delay and increased amplitude in the hUC-MSCs treated group compared with control and BSS groups. Higher cellular density was detected in the hUC-MSC treated group compared with the BSS and control groups. Co-localized expression of STEM 121 and anti-S100B antibody was observed in areas of higher nuclear density, both in the central and peripheral regions.Conclusion:Peribulbar transplantation of hUC-MSCs demonstrated cellular integration that can potentially preserve the optic nerve function with a significant shorter latency delay in fVEP and higher nuclear density on histology, and immunohistochemical studies observed cell migration particularly to the peripheral regions of the optic nerve.

Phacoemulsification and IOL-Implantation without Using Viscoelastics: Combined Modeling of Thermo Fluid Dynamics, Clinical Outcomes, and Endothelial Cell Density.

Phacoemulsification is a widely used surgical method in cataract surgery with a high energy ultrasound source. The viscoelastic is considered to be tissue protective. The aim of this study is to investigate during surgery the impact of using viscoelastic versus no viscoelastic on clinical outcomes, potential complications and effect on endothelial cell density. The study group included 64 patients, who were subjected to phacoemulsification using balanced salt solution (BSS). Control group consisted of 62 patients, who underwent phacoemulsification using Hyaloronic acid 1% Healon 1%. Student’s t-test was applied for statistical analysis. The simulations of temperature changes during phacoemulsification were performed by COMSOL Multiphysics software. In the BSS group, a mean endothelial cell loss (ECL) of 4.5% was measured one month postoperatively, while in the Healon group ECL was 5.3%. Data analysis showed no significant difference in ECL between the groups (Student’s t-test, p = 0.8). No significant difference was observed in endothelial cell morphology and IOP between the two groups pre- and postoperatively (all p > 0.05). The modeling of thermo fluid dynamics showed that the heating of the cornea is slightly less when Healon was used as irrigation fluid. The phacoemulsification technique can be performed by an experienced surgeon with viscoelastics or continuous anterior chamber (AC) irrigation on the same level of safety regarding endothelial cell damage, providing equally satisfying clinical outcomes.

Anti-inflammatory effects of glycine thymosin β4 eye drops in experimental dry eye.

The aim of the present study was to investigate the anti-inflammatory effects of glycine thymosin β4 (Gly-Tβ4) eye drops, and to compare the efficacy of topical Gly-Tβ4 with Cyclosporine A (CsA) in a mouse model of experimental dry eye (EDE). Eye drops consisting of balanced salt solution (BSS), 0.1% Gly-Tβ4 or 0.05% CsA were used for treatment of EDE. Tear volume, tear film break-up time and corneal staining scores were measured after 7 and 14 days. Periodic acid-Schiff staining for conjunctival gobleT cells, TUNEL assay for corneal apoptotic positive cells, multiplex immunobead assay for interleukin (IL)-1β, IL-6, tumor necrosis factor-α and interferon-γ levels, and flow cytometry for CD4+/CCR5+ T cells were performed after 14 days. All clinical parameters showed improvement in the Gly-Tβ4 and CsA groups (all P<0.05). Significantly increased conjunctival gobleT cells and decreased corneal TUNEL positive cells were observed in the Gly-Tβ4 and CsA groups. The Gly-Tβ4 and CsA treated groups showed significantly reduced inflammatory cytokine levels and T cells in the conjunctiva compared with the EDE and BSS groups (all P<0.05). However, there were no significant differences observed in the inflammatory and clinical parameters between the Gly-Tβ4 and CsA treatment groups. Topical application of 0.1% Gly-Tβ4 significantly reduced inflammation on the ocular surface, as well as clinical parameters of EDE, with a similar efficacy to that of 0.05% CsA emulsions, suggesting that Gly-Tβ4 eye drops may be used as a therapeutic agent for treatment of dry eye disease.

Choroidal changes after intravitreal injection of interferon alpha-2b.

Intravitreal injection of interferon alpha-2b (IFN-α2b) is used to treat uveitis but its effect on the choroid is unknown. We histologically evaluated the choroidal changes after intravitreal injection of IFN-α2b. We compared histological samples of IFN-α2b-injected eyes to eyes with lipopolysaccharide (LPS)-induced uveitis and eyes injected with balanced salt solution (BSS) as controls. Rabbit eyes received intravitreal injections of BSS, IFN-α2b, or LPS, and enucleation was done seven days later. Choroidal changes were evaluated on histological cut sections. The thickness of the choroid was measured in micrometer and the severity of inflammation was scored. The mean maximum choroidal thickness was significantly greater in the IFN-α2b group in comparison to the LPS and BSS groups ( P &lt; 0.001). The mean minimum choroidal thickness was also significantly greater in the IFN group compared to the BSS group ( P = 0.009). The observed changes were mainly due to vasodilation rather than interstitial fluid retention or inflammation. Mild inflammatory cell infiltration was observed in the choroid of four eyes in the IFN group and of three eyes in the LPS group. No inflammation was seen in the control group. The difference in inflammatory cell infiltration between the LPS and IFN groups was not statistically significant. Significant choroidal hyperemia was present after injection of IFN-α2b. This fact may suggest for some pharmacological applications of IFN-α2b when increased choroidal circulation is needed. However, further studies are required to elucidate the mechanisms involved.Impact statementType I interferons are proteins that are naturally secreted by cells in response to certain stimuli. They are approved for medical use to regulate immune responses in many disease states. Our findings of increased choroidal circulation after treatment of the eye with interferon alpha-2b indicate a possible effect of this cytokine on blood circulation. This is a novel finding that needs further investigation to elucidate mechanisms and applications.

Triphasic polymeric corneal coating gel versus a balanced salt solution irrigation during cataract surgery: A postoperative anterior segment optical coherence tomography analysis and confocal microscopy evaluation

To investigate the safety and efficacy of the intraoperative use of a triphasic polymeric gel as corneal coating during cataract surgery and its effect on postoperative ocular comfort. Eye Clinic, University of Florence, Italy. Longitudinal observational retrospective study. Data on patients who received an application of a polysaccharide blend of hydroxypropyl methylcellulose, xanthan gum, and carrageenan (EyeDRO) on the corneal surface and data on patients who received a balanced salt solution during phacoemulsification surgery were analyzed. The central corneal thickness (CCT) and epithelial thickness were examined using anterior segment optical coherence tomography, and the corneal basal epithelial cell (BEC) and Langerhans cell densities by invivo confocal microscopy. The ocular surface disease index (OSDI) score, tear breakup time (TBUT), and Schirmer test I values were evaluated. The study comprised data on 28 patients in the coating gel group and 26 patients in the balanced salt solution group. In the coating gel group, the CCT and epithelial thickness values returned to the baseline value within 5 and 15 postoperative days, respectively; the BEC and Langerhans cell densities returned to baseline levels within 15 and 30 postoperative days. In the balanced salt solution group, the mean BEC and Langerhans cell densities were significantly different from the preoperative values at all follow-up assessments. The TBUT returned to the preoperative level at day 5 in the coating gel group. The OSDI scores returned to the preoperative values after 15days in the coating gel group and 30days in the balanced salt solution group. The use of a tripolymeric gel as a corneal coating during cataract surgery played a protective role on the corneal surface and reduced postoperative discomfort symptoms.

Effect of Air Tamponade on Postoperative Visual Acuity and Intraretinal Cystoid Changes after Peeling of Idiopathic Epiretinal Membranes in Pseudophakic Patients

Purpose: Epiretinal membrane is a macular disorder leading to metamorphopsia and decreased visual acuity. The aim of the present study was to assess the possible effects of air tamponade, balanced salt solution (BSS), and combined phacoemulsification on functional and anatomical outcomes. Procedures: This prospective exploratory analysis included 72 eyes with idiopathic epiretinal membranes, scheduled to undergo 23-G pars plana vitrectomy with membrane peeling. Air tamponade or BSS was used in all cases. Optical coherence tomography (OCT) imaging was performed intraoperatively, and follow-up including visual acuity testing and OCT measurements was conducted until 3 months postoperatively. Results: Mean best-corrected visual acuity improved between +2.1 and +3.1 letters, and mean central subfield thickness of the macula decreased between –29.6 and –76 µm in the examined groups, without significant differences between the air tamponade and BSS groups. There was no significant difference in the presence of intraretinal cystoid changes between the groups. Conclusions: The use of air tamponade did not show any significant differences in the anatomical and functional postoperative results compared to BSS. Furthermore, phacovitrectomy did not result in significantly more intraretinal cystoid changes 3 months after surgery.

The Efficiency of Cyclosporine A-Eluting Contact Lenses for the Treatment of Dry Eye

ABSTRACTPurpose: To investigate the efficacy and safety of a new cyclosporine A (CsA) delivery system using contact lenses (CLs) for the treatment of experimental dry eye (EDE).Methods: CsA-laden porous carriers and CsA-eluting CLs were fabricated using the supercritical fluid technique. The release of CsA from carriers and CLs was investigated using high-performance liquid chromatography. The CsA concentrations in the cornea, conjunctiva, and crystalline lens of rabbits were measured. Dry eye was induced using 0.1% benzalkonium chloride in rabbits, which were subdivided into the normal, EDE, balanced salt solution (BSS), 0.05% CsA, hydrogel CL, or CsA-CL groups. Tear volume, tear film break-up time (TBUT), and corneal staining scores were measured at 1 and 2 weeks after treatment. Periodic acid-Schiff staining for the evaluation of conjunctival goblet cell density was performed at 2 weeks. Interleukin (IL)-1β, IL-6, tumor necrosis factor-α, and interferon-γ levels in the conjunctiva were measured using enzyme-linked immune-sorbent assay.Results: The porous carrier showed the release of drug. CsA-eluting CLs showed initial burst and sustained release of CsA until 48 h. The concentration of CsA elevated in the cornea, conjunctiva, and lens until 48 h after application of CsA-CLs. The CsA-CL group showed significantly higher tear volume, TBUT, and lower corneal staining scores compared to the other groups (p < 0.05). Goblet cell density was significantly higher in the CsA-CL group compared to the other groups. The CsA-CLs group showed a lower level of IL-1β than the BSS and soft CL groups (p < 0.01), and a lower level of IFN-γ than the other groups (all p < 0.01).Conclusions: The newly designed CsA-eluting CLs released drug continuously and showed good penetration in the eye. In addition, the use of CsA-eluting CLs improved clinical parameters and conjunctival goblet cell density and decreased inflammatory cytokines.

Balanced Salt Solution-Assisted Intraocular Lens Implantation in Phacoemulsification Surgery: Intraocular Pressure and Endothelial Cell Effects.

Objectives:The purpose of this study was to evaluate the effect of balanced salt solution (BSS)-assisted intraocular lens (IOL) implantation on postoperative intraocular pressure (IOP) and endothelial cells and to compare BSS-assisted IOL implantation with the use of ophthalmic viscosurgical devices during IOL implantation.Methods:A total of 52 eyes of 40 patients (25 female, 15 male) with a cataract who underwent phacoemulsification surgery with BSS-assisted (26 eyes) or viscoelastic-assisted IOL implantation (26 eyes) were evaluated. BSS-assisted IOL implantation was performed with the aid of irrigation cannula and BSS without using a viscoelastic substance. Viscoelastic-assisted IOL implantation was performed according to standard procedures to facilitate IOL implantation. IOP measurements and endothelial changes after phacoemulsification surgery, as well as the surgical time were noted and compared. The eyes were also evaluated in terms of cataract density preoperatively and phaco parameters were assessed peroperatively.Results:The mean age of the patients was 67.5±7.8 years in the BSS-assisted group and 67.8±9.4 years in the viscoelastic group. The mean preoperative IOP and postoperative IOP on day 1, week 1, and month 1 was 14.2±2.3, 14.7±3.1, 13.2±1.5, and 13.8±2.7 mmHg, respectively, for the BSS-assisted group and 14.1±2.9, 19.1±3.4, 13.8±3.1, and 13.2±2.9 mmHg, respectively, for the viscoelastic-assisted IOL implantation group. The IOP increase was significantly greater on the first day in the viscoelastic-assisted IOL implantation group (p=0.007). The surgical time was 12.3±2.1 minutes in the BSS group and 14.6±3.1 minutes in the viscoelastic group (p=0.035). The difference in endothelial changes was not statistically significant between groups (p=0.88).Conclusion:IOL implantation using BSS in phacoemulsification surgery is a reliable technique, and this method has a significantly shorter surgery time and a much smaller postoperative IOP increase. The reduced IOP increase after cataract surgery might be particularly helpful for glaucoma patients.

Thin Rigid Contact Lens Used in Vitreous-Retinal Surgery for Corneal Protection: A Randomized Controlled Trial.

To design a rigid contact lens (CL) to be used in combination with a wide-angle viewing system and analyze its protection for corneal epithelial during vitreous-retinal surgery. A thin and lightweight rigid CL was designed and constructed. The impact of the CL on the visualized fundus range was evaluated using a concrete eye model. Patients with severe proliferative diabetic retinopathy (PDR) were randomized to either the CL group, corneal protective agent (CPA) group, or balanced salt solution (BSS) group. All patients underwent phacoemulsification and a standard 23-gauge three-port vitrectomy. Surgery time and corneal fluorescein staining score (FSS) postoperatively were mainly measured. In the eye model, a larger area of fundus was visualized with the use of our CL under 128 D or 60 D Resight lens. The mean surgery time was 51.36±8.06 min, 50.89±8.26 min, and 55.46±9.14 in CL, CPA, and BSS group, respectively (F=2.325, P=0.105). In eight eyes in the BSS group, corneal epithelial layer was peeled off because the dryness of the cornea could not maintain a clear fundus image. The FSS in BSS group was markedly higher than that of CL and BSS group 1 day (P<0.001), 3 days (P<0.001), and 7 days (P=0.002) postoperatively. There was no statistical significance of the FSS between CL and CPA group at each follow-up endpoint. The CL that we designed can slightly enlarge the visible fundus range and efficiently protect corneal epithelium during vitrectomy for patients with PDR.

Effect of propolis on preserving human periodontal ligament cells and regulating pro-inflammatory cytokines.

Propolis has been suggested as a storage medium for avulsed teeth. The aim of this study was to compare the effectiveness of Brazilian propolis with Hank's balanced salt solution and milk in maintaining the viability of human periodontal ligament cells, their osteogenic differentiation potential, and pro-inflammatory cytokine expression. Cell Counting Kit 8 assays were performed to test human periodontal ligament cell viability in different storage media. The preservative effect on osteogenic differentiation was evaluated using alkaline phosphatase staining and activity assays, Alizarin Red S staining, and western blotting. Quantification of pro-inflammatory cytokines was performed using real-time PCR and enzyme-linked immunosorbent assays. Brazilian propolis at 10 μg/ml was not cytotoxic toward human periodontal ligament cells. The milk group showed the highest cell viability. Brazilian propolis and Hank's balanced salt solution groups showed similar cell viabilities. Alkaline phosphatase staining and activity were similar in all groups. Calcium deposition and mineralization nodule formation were similar in the Brazilian propolis and Hank's balanced salt solution groups, but were higher in the milk group. Osteogenic marker gene and protein levels were similar in all groups. The genes and protein expression levels of IL1β, IL6, and IL8 decreased significantly after treatment with Brazilian propolis. TNFα mRNA expression showed no significant difference among the experimental groups. Pro-inflammatory cytokine levels in the milk group were higher than in the Brazilian propolis and Hank's balanced salt solution groups. Brazilian propolis, Hank's balanced salt solution, and milk maintained the viability of human periodontal ligament cells and preserved their osteogenic differentiation ability similarly. However, Brazilian propolis showed a better anti-inflammatory effect. This article is protected by copyright. All rights reserved.

The influence of human umbilical cord mesenchymal stem cells transplanted into the tail vein of diabetic rats on apoptosis of retinal neurons and the retinal expression of glial fibrillary acidic protein

Objective To observe the influence of human umbilical cord mesenchymal stem cells(hUCMSC) transplanted into the tail vein of diabetic rats on apoptosis of retinal neurons and the retinal expression level of glial fibrillary acidic protein (GFAP). Methods Seventy clean male Sprague-Dawley rats were randomly divided into the normal control group (group A), diabetes mellitus (DM) only group (group B), DM + balanced salt solution (BSS) group (group C), DM + hUCMSC group (group D), with 10 rats in each group. DM rats were induced by intraperitoneal injection of streptozotocin. Apoptosis of retinal cells was assayed by dUTP nick end labeling. Immunohistochemistry and Western blot was performed to detect the retinal expressions of GFAP in rats. Results Compared with group A, large numbers of apoptotic cells could be found in the retinal ganglion cell layer (GCL) and inner nuclear layer (INL) of group B and group C, however the apoptotic cells in group D were significantly reduced than group B and C. The expression of GFAP was mainly located in the retinal GCL and retinal nerve fibre layer (RNFL) in group A, throughout the inner plexiform layer(IPL) in group B and C, only distributed in RNFL and GCL in group D. It was obvious that the expression of GFAP in group B and C was higher than group A. Compared with group B and C, the expression of GFAP in group D was significantly reduced. The difference of GFAP expression among the 4 groups was significant(F=79.635, P<0.05). Conclusion hUCMSC could inhibit the apoptosis of retinal cells and activation of glial cells in early DM rats. Key words: Diabetic retinopathy; Mesenchymal stem cells; Neurons; Apoptosis

The effect of netrin-1 on activation of Mueller cell in diabetes rats

Objective To observe the effect of netrin-1 on retinal Muller cells in diabetes mellitus (DM) rats. Methods Fifty Sprague-Dawley rats were randomly divided into the normal control group (group A), normal + balanced salt solution (BSS) group (group B), normal+netrin-1 group (group C), DM+BSS group (group D) and DM+netrin-1 group (group E), with 10 rats in each group. DM rats were induced by intraperitoneal injection of Streptozotocin (60 mg/kg). The expression level of glial fibrillary acidic protein (GFAP) on retinal Muller cells was determined by immunohistochemistry, the level of GFAP mRNA was analyzed by real-time fluorescence quantitative reverse transcription polymerase chain reaction. Results Immunohistochemistry showed that GFAP was distributed in retinal ganglion cells and retinal nerve fiber layer in group A, B and C. Compared to group B, GFAP staining was brighter in the group D. There were significant differences in the expression of GFAP protein and mRNA among groups A-E (F=203.43, 72.91; P=0.00, 0.00), they were higher in group D than group A (t=−26.01, 22.26; P=0.00, 0.00), and group E (t=−10.78, 3.93; P=0.00, 0.00). They were higher in group E than group A (t=7.00, −9.82; P=0.00, 0.00). There were no significant differences in between group A and group C (t=−0.29, 0.50; P=0.77, 0.62). Conclusion The expression of GFAP in Muller cells of DM rats could be decreased by injecting netrin-1 into vitreous. Key words: Diabetic retinopathy/physiopathology; Microglia/physiology; Nerve growth factors; Animal experimentation

The effect of netrin-1 on the retinal vascular permeability in diabetes mellitus rats

Objective To observe the effect of different concentration netrin-1 on retinal vascular permeability in diabetes mellitus (DM) rats. Methods Eighty adult Sprague-Dawley rats were randomly divided into 8 groups, 10 rats in each group, including normal control group (group A), normal+ balanced salt solution (BSS) group (group B), normal+ netrin-1 (500 μg/ml) group (group C) and DM group (50 rats in 5 subgroups). DM rats were induced by intraperitoneal injection of streptozocin. Three months after intraperitoneal injection, 10 DM rats in the control group were injected with BSS (group D). Forty DM rats were injected with 5 μl of different concentrate netrin-1, and were divided into DM+netrin-1 10 μg/ml group (group E), DM+netrin-1 50 μg/ml group (group F), DM+ netrin-1 100 μg/ml group (group G), DM+ netrin-1 500 μg/ml group (group H) according to the different concentration. Non-DM rats in group C were injected with netrin-1 500 μg/ml. The expression of occludin was determined by immunohistochemistry for protein, and by real-time fluorescence quantitative reverse transcription polymerase chain reaction for mRNA level. Retinal vascular permeability was measured by Evans blue infusion. Results The expression of occludin protein and mRNA in group D were less than group A (t=27.71, 8.59; P=0.00, 0.00). However, the retinal vascular permeability increased in group D (t=-42.72, P=0.00). The expression of occluding protein, occludin mRNA and retinal vascular permeability showed significant differences between group D, E, F, G and H (F=146.31, 16.54, 67.77; P=0.00, 0.00, 0.00). Compared the group B with group C, there was no significant differences between the expression of occludin protein, occludin mRNA and the retinal vascular permeability (t=-1.13, 0.93, 1.04; P=0.27, 0.36, 0.31). The concentrate of netrin-1 showed a significant positive correlation to the expression level of occludin and occludin mRNA (r=0.73, 0.81; P=0.00, 0.00), but negative correlation to the vascular permeability (r=-0.61, P=0.00). Conclusion Netrin-1 can reduce the DM rats' retinal vascular permeability, which depended on the concentration of netrin-1. Key words: Diabetic retinopathy/physiopathology; Blood retinal barrier/physiopathology; Nerve growth factors; Animal experimentation

Characterization of a Standardized Ex-vivo Porcine Model to Assess Short Term Intraocular Pressure Changes and Trabecular Meshwork Vitality After Pars Plana Vitrectomy with Different Silicone Oil and BSS Tamponades

ABSTRACTPurpose: The aim of this study was to characterize a standardized porcine ex-vivo testing system for intraocular pressure (IOP) monitoring after vitrectomy with different endotamponades.Methods: Twenty-four pig eyes, six per endotamponade group were obtained immediately postmortem. After pars plana vitrectomy, vitreous substitutes (silicone oil 1000 mPas, 2000 mPas, 5000 mPas, and Balanced Salt Solution (BSS)) were instillated and IOP was observed over 24-hours. Infusion pumps with Dulbecco’s Modified Eagle Medium (DMEM) simulated a constant aqueous humor circulation. A histological examination of the trabecular meshwork with DAPI- and TUNEL-staining was performed to detect the amount of apoptotic cells.Results: TUNEL-assay showed a mean cell death rate of 3.78% (SD ± 1.46%) for silicone oil endotamponades compared to 5.05% (SD ± 2.18%) in BSS group. One-way ANOVA (p = 0.425) showed no significant difference between both groups. Mean IOP in silicone oil endotamponades was 9.50 mmHg (SD ± 1.68 mmHg) at baseline, 13.23 mmHg (SD ± 0.79 mmHg) after 1 hour, 18.46 mmHg (SD ± 2.13 mmHg) after 12 hours and 15.51 mmHg (SD ± 2.82 mmHg) 24 hours after instillation. A comparison of all silicone oil groups (one-way ANOVA, Bonferroni post-hoc test, p = 0.269 to 1.000) didn’t reveal significant differences in mean IOP.Conclusion: The standardized ex-vivo porcine model represents an effective alternative to the in-vivo testing in animals. Maintaining the trabecular and uveoscleral outflow pathway enables a pseudo in-vivo analysis.