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Purpose: To evaluate the anti‐haze effect and visual outcome after intraoperative mitomycin C (MMC) use during photorefractive keratectomy (PRK) in myopia or myopic astigmatism patients. Methods: We searched in PubMed, EMBASE, Cochrane Library and Google Scholar comprehensively to obtain studies comparing the clinical effects after PRK with and without MMC published until February 2020. Meta‐analysis of primary outcome (corneal haze rate) and secondary outcomes [predictability, efficacy, safety and corneal endothelial cell density (ECD)] were conducted. We used trial sequential analysis (TSA) in an effort to collect firm evidence supporting our conclusion. Results: Of the included 11 randomized controlled trials, five cohort and one case–control studies, 3536 eyes (2232 and 1304 in the MMC and control groups, respectively) were enrolled for meta‐analysis. The TSA disclosed strong evidence of decline in corneal haze rate in the MMC group compared with that of the control group. In the subgroup analysis of duration, MMC seemed to reduce corneal haze rate in early‐onset and late‐onset haze. Predictability of refraction and visual acuity were greater in the MMC groups, not significantly though. The proportion of patients losing at least two lines of best corrected visual acuity postoperatively in the MMC groups was lower than that in the control groups. The corneal postoperative ECD showed no significant difference between the MMC and control groups. Conclusion: Our meta‐analysis revealed that MMC is an important anti‐haze agent in PRK for reducing both early‐ and late‐onset haze and can also help improving predictability of refraction and subjective postoperative visual acuity. [ABSTRACT FROM AUTHOR]

Abstract Objective To develop a surgical approach for cell transplantation into mouse cochlear nerves via an intracranial route and investigate whether transplantation of human limbus–derived mesenchymal stromal cells (HL-MSCs) can improve hearing in this model of auditory neuropathy. Methods We used 8-week-old CBA/CaJ male mice and created ouabain-induced auditory neuropathy. The surgical approach passed through the cerebellum to reveal the superior semicircular canal and brainstem, allowing access to the auditory nerve. Then HL-MSCs were injected around the cochlear nerve trunk using a micropipette driven by a micropump. Hearing thresholds in the mice were determined by auditory brainstem responses (ABRs) and distortion product otoacoustic emissions (DPOAEs). Results We produced ouabain-induced neuropathy in mice with an elevated hearing threshold but normal DPOAE. Using immunohistological staining, we detected HL-MSCs were localized in the cochlear nerve trunk 2 days after cell transplantation via this occipital approach. More spiral ganglion neurons were detected in ouabain-treated cochleae 3 months after HL-MSCs transplantation compared to those without HL-MSCs transplantation. The ABR showed significant hearing improvement 3 months after HL-MSCs transplantation. Conclusions We successfully established a mouse model for cell transplantation into the intracranial cochlear nerve trunk and showed that HL-MSCs potentially can be applied as cell therapy to treat sensorineural hearing loss. [ABSTRACT FROM AUTHOR]

. Purpose: To investigate the effect of silibinin in myofibroblast transdifferentiation and in animal trabeculectomy models. Methods: The effect of silibinin on the expression of α-smooth muscle actin (α-SMA) and vimentin in response to transforming growth factor-β1 (TGF-β1) was determined in human tenon fibroblasts (HTFs). Cell migration and collagen contraction arrays were used to demonstrate the functionality of silibinin-modulated HTFs. ELISA analysis was used to determine the effect of silibinin on the release of type 1 collagen and connective tissue growth factor (CTGF). The effect of silibinin on the activation of the TGF-β receptor-related pathway was evaluated by Western blotting. A rabbit model of trabeculectomy was established to assess the effect of silibinin in vivo. Results: TGF-β1 elevated the expression of α-SMA and vimentin in HTFs; this elevation was inhibited by silibinin. TGF-β1 increased cell migration and collagen contraction of HTFs, which were also suppressed by silibinin. The production of both CTGF and type 1 collagen in TGF-β1-treated HTFs was inhibited by silibinin. The effects of silibinin on TGF-β1-stimulated HTFs were mediated via the down-regulation of TGF-β receptor-related SMAD signalling pathways. In the rabbit model of trabeculectomy, silibinin increased the period of decreasing intraocular pressure after trabeculectomy and reduced the production of collagen and α-SMA at the site of blebs in vivo. Conclusion: Silibinin inhibited the TGF-β receptor-related signalling pathway in TGF-β-treated HTFs and several of the downstream events associated with myofibroblast transdifferentiation. Silibinin also improved the outcome of trabeculectomies by reducing the fibrotic response in the bleb tissue in vivo. [ABSTRACT FROM AUTHOR]

Background: To evaluate the outcomes of Descemet-stripping automated endothelial keratoplasty (DSAEK) with the use of continuous air pumping technique in Asian eyes with previous Ahmed glaucoma valve implantation. Methods: The DSAEK procedure was modified in that complete air retention of the anterior chamber was maintained for 10 min using continuous air pumping at 30 mm Hg. The primary outcome measurement was graft survival, and postoperative clinical features including, rate of graft detachment, endothelial cell count, intraocular pressure (IOP), surgical time and cup/disc ratio were also recorded. Results: A total of 13 eyes of 13 patients which underwent modified DSAEK and 6 eyes of 6 patients which underwent conventional DSAEK were included. There was a significant difference in graft survival curves between two groups (P = 0.029); the 1-year graft survival rates were estimated as 100% and 66.7% for patients with modified DSAEK and those with traditional DSAEK, respectively. The rate of graft detachment were 0% and 33.3% for the modified DSAEK and conventional DSAEK groups, respectively (P = 0.088). The significantly lowered surgical time for air tamponade was noted in the modified DSAEK group compared to that in the conventional DSAEK group [median (IQR): 10.0 (10.0, 10.0) min vs. 24.5 (22.0, 27.0) min; P<0.001] Postoperatively, patients in the modified DSAEK group had significantly lower IOP as compared to the conventional DSAEK group [12.0 (11.0, 15.0) mm Hg vs. 16.0 (15.0, 18.0) mm Hg; P = 0.047]. Modified DSAEK patients had higher endothelial cell counts as compared to conventional DSAEK patients [2148.0 (1964.0, 2218.0) vs. 1529.0 (713.0, 2014.0)], but the difference did not reach statistical significance (P = 0.072). Conclusions: New continuous air pumping technique in DSAEK can be performed safely and effectively in patients with prior GDDs placement who have corneal failure. [ABSTRACT FROM AUTHOR]

. Purpose: To investigate the effect of bevacizumab treatment on connective tissue growth factor (CTGF) expression and the induction of epithelial-to-mesenchymal transition in ARPE-19 cells and human donor retinal pigment epithelium (HRPE) cells in vitro. Methods: We quantitated the protein and gene expression level of CTGF by ELISA. The effect of Fc-Fc receptor (Fc-FcR) interaction on CTGF expression was evaluated by CD64 siRNA silencing. Expression of epithelial-to-mesenchymal transition markers, alpha-smooth muscle actin (α-SMA) and zona occludens protein (ZO-1) was evaluated by Western blot. Cell migration and collagen gel contraction assay were examined by light microscopy, and collagen production was measured by ELISA. Results: Bevacizumab stimulation increased CTGF expression in ARPE-19 and HRPE cells in a dose-dependent manner. CD64 gene silencing inhibited the effect of bevacizumab-induced CTGF up-regulation. Bevacizumab increased the expression of α-SMA and decreased the expression of ZO-1 in ARPE-19 cells. Bevacizumab also caused the release of type-1 collagen and increased cell migration and contraction of collagen. Conclusions: Bevacizumab exerts pro-fibrotic effects on human RPE cells at clinical doses by up-regulation of CTGF expression via an Fc-FcR interaction. This effect of bevacizumab may be one of the underlying mechanisms involved in age-related macular degeneration therapy or intravitreal bevacizumab-associated complications. [ABSTRACT FROM AUTHOR]

Meibomian gland dysfunction and dry eye disease are closely related conditions that often coexist and can contribute to the development of each other. Understanding the similarities and differences between these diseases can assist clinicians in implementing effective treatments for both conditions in a clinical setting. Dry eye disease is a multifactorial disease of the tears and ocular surface. This study aimed to evaluate the demographic characteristics of patients with meibomian gland dysfunction in Taiwan, investigate the association between meibomian gland dysfunction and dry eye parameters, and estimate the prevalence of meibomian gland dysfunction among patients with dry eye symptoms at a tertiary referral centre. This cross-sectional study enrolled patients aged ≥20 years who complained of dry eye symptoms and visited a tertiary centre between September 2019 and March 2020. The patients completed the Ocular Surface Disease Index and Standard Patient Evaluation of Eye Dryness questionnaires before undergoing ocular examination. The lipid layer thickness and meiboscale scores were recorded. In addition, the study measured tear film break-up time, examined corneal staining, and evaluated the number of meibomian glands yielding liquid secretions using a slit lamp. The study evaluated 202 eyes of 202 patients with a mean age of 58.05 ± 13.34 years. The prevalence of meibomian gland dysfunction was 93%. Mean meiboscale score and age were negatively associated, and tear film break-up time was positively associated with the mean number of meibomian glands yielding liquid secretions. Hyperlipidaemia and smoking were the main risk factors for Meibomian gland dysfunction. The prevalence of meibomian gland dysfunction among patients with dry eye symptoms was extremely high at the tertiary centre, highlighting the strong relationship between Meibomian gland dysfunction and dry eye disease. Clinicians should consider meibomian gland dysfunction as a possible cause of dry eye. [ABSTRACT FROM AUTHOR]

Background: Doctors can detect symptoms of diabetic retinopathy (DR) early by using retinal ophthalmoscopy, and they can improve diagnostic efficiency with the assistance of deep learning to select treatments and support personnel workflow. Conventionally, most deep learning methods for DR diagnosis categorize retinal ophthalmoscopy images into training and validation data sets according to the 80/20 rule, and they use the synthetic minority oversampling technique (SMOTE) in data processing (e.g., rotating, scaling, and translating training images) to increase the number of training samples. Oversampling training may lead to overfitting of the training model. Therefore, untrained or unverified images can yield erroneous predictions. Although the accuracy of prediction results is 90%–99%, this overfitting of training data may distort training module variables. Results: This study uses a 2-stage training method to solve the overfitting problem. In the training phase, to build the model, the Learning module 1 used to identify the DR and no-DR. The Learning module 2 on SMOTE synthetic datasets to identify the mild-NPDR, moderate NPDR, severe NPDR and proliferative DR classification. These two modules also used early stopping and data dividing methods to reduce overfitting by oversampling. In the test phase, we use the DIARETDB0, DIARETDB1, eOphtha, MESSIDOR, and DRIVE datasets to evaluate the performance of the training network. The prediction accuracy achieved to 85.38%, 84.27%, 85.75%, 86.73%, and 92.5%. Conclusions: Based on the experiment, a general deep learning model for detecting DR was developed, and it could be used with all DR databases. We provided a simple method of addressing the imbalance of DR databases, and this method can be used with other medical images. [ABSTRACT FROM AUTHOR]

Corneal epithelial healing after refractive surgery is a clinically significant issue, especially for surface ablation procedures, and this can be monitored using optical coherence tomography (OCT). The aim of this work is to investigate the corneal epithelial thickness and irregularity by OCT after transepithelial photorefractive keratectomy (t-PRK) and analyse its correlation with visual and refractive outcomes. Patients aged ≥18 years with myopia, with or without astigmatism, who underwent t-PRK between May 2020 and August 2021 were included. All participants were subjected to complete ophthalmic examinations and OCT pachymetry at every follow-up visit. Patients were followed up at 1 week and 1, 3, and 6 months postoperatively. A total of 67 patients (126 eyes) were enrolled in this study. One month postoperatively, spherical equivalent refraction and visual acuity achieved preliminary stability. However, central corneal epithelial thickness (CCET) and standard deviation of the corneal epithelial thickness (SDcet) took 3–6 months to progressive recovery. Patients with higher baseline spherical equivalent refraction were associated with slower epithelial recovery. At every follow-up time point, a significant superior-inferior difference in the minimum corneal epithelial thickness area was observed. Higher stromal haze was correlated with higher spherical equivalent refraction (both baseline and residual) but had no relation with visual outcomes. There was a significant correlation between higher CCET with a better uncorrected distance visual acuity and lower corneal epithelial thickness irregularity. CCET and SDcet measured by OCT seem to be a good auxiliary indicator for reflecting the status of corneal wound recovery after t-PRK surgery. However, a well-designed randomised control study is needed to confirm the study results. [ABSTRACT FROM AUTHOR]

Uveitis, an intraocular inflammatory disease, occurs mostly in young people and can result in the loss of socioeconomic capabilities. Silibinin has been shown to exert anti-inflammatory effects in human retinal pigment epithelial (RPE) cells. The present study investigated the anti-inflammatory effect of silibinin pretreatment on endotoxin-induced uveitis (EIU) in rats and the mechanisms by which it exerts these effects. Uveitis was induced via injection of lipopolysaccharides (LPS) into Lewis rats. Twenty-four hours after the LPS injection, histological examination showed that silibinin decreased inflammatory cell infiltration in the anterior segment of the eyes of LPS-treated rats. Analyses of the aqueous humor showed that silibinin decreased cell infiltration, protein concentration, nitric oxide (NO), and prostaglandin (PG)-E2 production. Western blot analysis indicated that silibinin decreased the expression of inducible NO synthase (iNOS), cyclooxygenase (COX-2), and phosphorylated IkB in the iris-ciliary body (ICB). Immunohistochemistry showed that silibinin decreased intercellular adhesion molecule (ICAM-1) expression in the ICB. In addition, western blot analysis showed that silibinin attenuated the expression of iNOS, COX-2, ICAM-1, and nuclear p65 in LPS-treated RAW cells. In conclusion, silibinin pretreatment prevents EIU and the subsequent production of proinflammatory mediators and ICAM-1, at least in part, by blocking the NF-κB–dependent signaling pathway both in vivo and in vitro. These effects may contribute to the silibinin-mediated preventive effects on intraocular inflammatory diseases such as acute uveitis. [ABSTRACT FROM AUTHOR]

Benign smooth muscle tumor, leiomyoma, can occur throughout the whole body, including the most common sites of the genitourinary and gastrointestinal tracts, less frequently in the skin, and rarely in the deep soft tissue or uveal tract. A 23-year-old Chinese woman presented with a 4 month history of a pigmented ciliary body mass in her left eye. The tumor's clinical appearance and ancillary data were initially consistent with malignant melanoma. However, instead of enucleation, sclerotomy with a tumor biopsy was performed because of the patient's young age and the possibility of benign tumors. Under light microscopy, tumor cells were short spindle- or ovoid-shaped with fine nuclear chromatin and fibrillary cytoplasmic processes resembling neural tissue. Although the tumor displayed neurogenic morphology, it showed strong reactivity for α-smooth muscle-specific actin and h-caldesmon, and was negative for neurogenic markers, except CD56, by immunohistochemistry. Primary mesectodermal leiomyoma of the ciliary body was diagnosed because of both the myogenic and neurogenic characteristics. The tumor biopsy or intraoperative frozen section is suggested for accurate pathological diagnosis before enucleation. In a review of the literature, only 14 cases have been reported. Seven cases (50%) were subjected to enucleation and eventually showed a benign mesectodermal leiomyoma. This case report provides novel expression of h-caldesmon and CD56 by the tumor cells of mesectodermal leiomyoma. [ABSTRACT FROM AUTHOR]

Corneal scarring is a common poor outcome of corneal trauma. Transforming growth factor β-1 plays a vital role in corneal fibrosis, inducing keratocyte transformation to myofibroblasts. Other than corneal transplantation, no other curative treatment methods for corneal scarring are currently available. Hypercapnic acidosis exerts anti-inflammatory and anti-migratory effects on numerous organs; however, its effect on corneal fibroblasts remains unknown. Hence, this study aimed to evaluate the effect of hypercapnic acidosis on transforming growth factor β-1-induced fibrosis in corneal fibroblasts and to elucidate the underlying mechanisms. Corneal fibroblasts were obtained from human limbal tissue and cultured with or without transforming growth factor β-1 under hypercapnic acidosis or no-hypercapnic acidosis conditions, and subjected to scratch wound, cell migration, and collagen matrix contraction assays. Furthermore, immunocytochemistry was performed to evaluate the alpha-smooth muscle actin stress fiber. Finally, western blotting was performed to assess the expression of proteins in the NF-κB and Smad pathways. Hypercapnic acidosis suppressed collagen gel contraction capacity in transforming growth factor β-1-treated corneal fibroblasts and inhibited transforming growth factor β-1-induced cell migration. Moreover, hypercapnic acidosis downregulated corneal fibrosis marker alpha-smooth muscle actin in transforming growth factor β-1-treated corneal fibroblasts. Furthermore, hypercapnic acidosis suppressed transforming growth factor β-1-induced fibrosis, at least partly, by inhibiting Smad2/3 phosphorylation and down-regulating p-IκB-dependent and RelB signaling transduction. Hypercapnic acidosis inhibits transforming growth factor β-1-induced corneal fibroblast migration, collagen gel contraction capacity, and alpha smooth muscle actin expression, potentially through the Smad and NF-κB pathways. Therefore, hypercapnic acidosis may be a potentially useful anti-fibrotic therapy for corneal scarring. [ABSTRACT FROM AUTHOR]

This population-based retrospective cohort study investigated the prevalence of myopia among patients with Type 1 and Type 2 diabetes mellitus (DM) and evaluate risk factors for myopia in these groups. Records from 2000 to 2012 with at least one year of follow-up from the Taiwan National Health Insurance Research Database were included. This study included 35,538 patients with DM and 71,076 patients without DM. Patients with DM had a significantly higher adjusted hazard ratio for myopia in all age groups and both sexes compared with patients without DM. The subgroup analysis results revealed that the rates of myopia and astigmatism were significantly higher among patients with DM compared with patients without DM aged < 60 years. However, the rates of high myopia or myopia progression to high myopia did not differ significantly between the two groups. These findings indicate that DM is a critical risk factor for myopia and astigmatism among patients aged < 60 years. Therefore, active surveillance and earlier treatment of myopia are critical for patients with DM. [ABSTRACT FROM AUTHOR]

Purpose: We assessed whether mitomycin-C (MMC) has different antifibrotic mechanisms in trabeculectomy wound healing. Methods: We identified 2 concentrations of MMC as "low-dose" by using WST-1 assay, Lactic dehydrogenase assay, and fluorescence-activated cell sorting flow cytometry. Senescence-associated β-galactosidase (SA-β-gal) and fibrotic gene expression was examined through immunocytochemistry, flow cytometry, real-time quantitative reverse transcription polymerase chain reaction, Western blotting, zymography, and modified scratch assay in vitro. In vivo, 0.1 mL of MMC or normal saline was injected to Tenon's capsule before trabeculectomy in a rabbit model. SA-β-gal expression, apoptotic cell death, and collagen deposition in sites treated and not treated with MMC were evaluated using terminal dUTP nick end labeling assay and histochemical staining. Bleb function and intraocular pressure (IOP) levels were examined 3, 7, 14, 21, 28, and 35 days after trabeculectomy. Results: In vitro, human Tenon's fibroblast (HTF) senescence was confirmed by observing cell morphologic change, SA-β-gal accumulation, formation of senescence-associated heterochromatin, increased p16INK4a and p21CIP1/WAF1 expression, lower percentage of Ki-67-positive cells, and decreased COL1A1 release. Increased expression of α-SMA, COL1A1, and Smad2 signaling in TGF-β1-induced stress fibers were passivated in senescent HTFs. In addition, cellular migration enhanced by TGF-β1was inactivated. In vivo, histological examination indicated increased SA-β-gal accumulation, lower apoptosis ratios, and looser collagen deposition in sites treated with 0.2 μM MMC. Low-dose MMC-induced cellular senescence prolonged trabeculectomy bleb survival and reduced IOP levels in a rabbit model. Conclusion: Low-dose MMC-induced cellular senescence is involved in the antifibrotic mechanism of trabeculectomy wound healing. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to evaluate the relationship between diabetic mellitus (DM) treatment and the incidence rate of endogenous endophthalmitis (EE). Design: This study used a matched cohort design. We utilized the Longitudinal Health Insurance Database to identify outpatients and inpatients who were diagnosed with DM and treated with medication from 2000 to 2010. Methods: Several factors and different DM medications were also investigated. The influence of DM medication on the incidence of EE was examined by using Cox proportional hazards regression models, and the hazard ratios and 95% confidence intervals were determined. Results: The cumulative incidence of EE was lower in DM patients treated with medication than in subjects in the control group (P = 0.002). The adjusted hazard ratio (AHR) was 0.47-fold lower in the treatment group than in the control group (P = 0.004). With respect to DM medication, single-agent therapy with insulin, metformin, gliclazide, glimepiride, or repaglinide and combination therapy with glimepiride/metformin or repaglinide/metformin were associated with decreased AHRs (0.257–0.544, all P<0.05). Conclusions: Diabetic patients treated with medication had lower AHRs than those in the control group. Further stratification indicated that liver abscess, liver disease DM patients who were treated with medication had a lower risk of developing EE. Several specific DM medications may decrease the incidence of EE. [ABSTRACT FROM AUTHOR]

Ischemia–reperfusion (I/R) injury is associated with numerous retinal diseases, such as diabetic retinopathy, acute glaucoma, and other vascular retinopathies. Hypercapnic acidosis (HCA) has a protective effect on lung, myocardial, and central nervous system ischemic injury models. However, no study has evaluated its protective effects in an experimental retinal I/R injury model. In this study, retinal I/R injury was induced in Sprague Dawley rats by elevating the intraocular pressure to 110 mmHg for 60 minutes. HCA was induced before and after the injury. After 24 hours, the terminal dUTP nick end labeling assay was performed. Moreover, the ratios of cleaved caspase-3/total caspase-3, phosphorylated IκB/IκB, and phosphorylated p38 were measured through Western blotting. After 7 days, the rats’ aqueous humor was analyzed. In addition, electroretinography and retinal thickness measurement were performed in the rats. Moreover, the retinal neural cell line RGC-5 was exposed to 500 μM H2O2 for 24 hours to induce a sustained oxidative stress in vitro. The effects of HCA were evaluated by comparing oxidative stress, MAPK signals, NF-κB signals, survival rates, and apoptosis rates in the RGC-5 cells before and after H2O2 exposure. We further investigated whether the potent I/R-protective heat shock protein (HSP) 32 contribute to protective effects of HCA. Our results indicated that HCA has protective effects against retinal I/R injury both in vivo and in vitro, at multiple levels, including antiapoptotic, anti-inflammatory, antioxidative, and functional retinal cell protection. Further research clarifying the role of HCA in retinal I/R injury prevention and treatment is warranted. [ABSTRACT FROM AUTHOR]

Age-related macular degeneration (AMD) is a vision-threatening age-associated disease. The retinal pigment epithelial (RPE) cells phagocytose and digest photoreceptor outer segment (POS). Incomplete digestion of POS leads to lipofuscin accumulation, which contributes to the pathology of the AMD. Autophagy could help reduce the amount of lipofuscin accumulation. In the present study, we evaluated the effects of glucosamine (GlcN), a natural supplement, on the induction of autophagy and POS-derived lipofuscin-like autofluorescence (LLAF) in ARPE-19 cells in vitro, and investigated the potential molecular pathway involved. Our results revealed that GlcN had no effect on phagocytosis of POS at the lower doses. GlcN treatment induced autophagy in cells. GlcN decreased the LLAF in native POS-treated cells, whereas malondialdehyde or 4-hydroxynonenal-modified POS attenuated this effect. 3-Methyladenine inhibited GlcN-induced autophagy and attenuated the effect of GlcN on the decrease of the native POS-derived LLAF. Furthermore, GlcN induced the phosphorylation of AMP-activated protein kinase (AMPK) and inhibited the phosphorylation of mammalian target of rapamycin (mTOR), whereas Compound C inhibited these effects of GlcN. Altogether, these results suggest that GlcN decreased the native POS-derived LLAF through induction of autophagy, at least in part, by the AMPK–mTOR pathway. This mechanism has potential for the preventive treatment of lipofuscin-related retinal degeneration such as AMD. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effects of silibinin on cell proliferation in platelet-derived growth factor (PDGF)-treated human Tenon's fibroblasts (HTFs). The effect of silibinin on cell proliferation in PDGF-treated HTFs was determined by examining the expression of proliferating cell nuclear antigen (PCNA) and performing WST-1 assays. Cell cycle progression was evaluated using flow cytometry. The related cyclins and cyclin-dependent kinases (CDKs) were also analyzed using western blot. A modified rat trabeculectomy model was established to evaluate the effect of silibinin on cell proliferation in vivo. Western blot analysis was carried out to determine the effect of silibinin on the expression of PDGF receptor and on the downstream signaling pathways regulated by PDGF receptor. PDGF elevated the expression of PCNA in HTFs, and this elevation was inhibited by silibinin. The inhibitory effect of silibinin on cell proliferation was also confirmed via WST-1 assay. PDGF-stimulated cell cycle in HTFs was delayed by silibinin, and the related cyclin D1 and CDK4 were also suppressed by silibinin. In the rat model of trabeculectomy, silibinin reduced the expression of PCNA at the site of blebs in vivo. The effects of silibinin on PDGF-stimulated HTFs were mediated via the downregulation of PDGF receptor-regulated signaling pathways, such as ERKs and STATs, which may be partially caused by the downregulation of N-glycosylation of PDGF receptor beta (PDGFRβ). The effect of silibinin on modulation of N-glycosylation of PDGFRβ was mediated in a proteasome-dependent manner. Silibinin inhibited cell proliferation and delayed cell cycle progression in PDGF-treated HTFs in vitro. PDGF also modulated the process of N-glycosylation of the PDGFRβ in a proteasome-dependent manner. Our findings suggest that silibinin has potential therapeutic applications in glaucoma filtering surgery. [ABSTRACT FROM AUTHOR]

Autophagic (type II) cell death, characterized by the massive accumulation of autophagic vacuoles in the cytoplasm of cells, has been suggested to play pathogenetic roles in cerebral ischemia, brain trauma, and neurodegenerative disorders. 3,4-Methylenedioxymethamphetamine (MDMA or ecstasy) is an illicit drug causing long-term neurotoxicity in the brain. Apoptotic (type I) and necrotic (type III) cell death have been implicated in MDMA-induced neurotoxicity, while the role of autophagy in MDMA-elicited neurotoxicity has not been investigated. The present study aimed to evaluate the occurrence and contribution of autophagy to neurotoxicity in cultured rat cortical neurons challenged with MDMA. Autophagy activation was monitored by expression of microtubule-associated protein 1 light chain 3 (LC3; an autophagic marker) using immunofluorescence and western blot analysis. Here, we demonstrate that MDMA exposure induced monodansylcadaverine (MDC)- and LC3B-densely stained autophagosome formation and increased conversion of LC3B-I to LC3B-II, coinciding with the neurodegenerative phase of MDMA challenge. Autophagy inhibitor 3-methyladenine (3-MA) pretreatment significantly attenuated MDMA-induced autophagosome accumulation, LC3B-II expression, and ameliorated MDMA-triggered neurite damage and neuronal death. In contrast, enhanced autophagy flux by rapamycin or impaired autophagosome clearance by bafilomycin A1 led to more autophagosome accumulation in neurons and aggravated neurite degeneration, indicating that excessive autophagosome accumulation contributes to MDMA-induced neurotoxicity. Furthermore, MDMA induced phosphorylation of AMP-activated protein kinase (AMPK) and its downstream unc-51-like kinase 1 (ULK1), suggesting the AMPK/ULK1 signaling pathway might be involved in MDMA-induced autophagy activation. [ABSTRACT FROM AUTHOR]

Background: To assess the efficacy and safety of anterior chamber paracentesis (ACP) and the changes in pH values in eyes with acute primary angle closure (APAC). Methods: This retrospective case-control study involved 22 patients with APAC who underwent ACP (study group) and 21 patients with APAC who did not undergo ACP (control group). Intraocular pressure (IOP) and visual acuity were measured before treatment and 15 min and 24 h after treatment in both groups. The pH of aqueous humor was measured immediately after ACP in the study group. Results: A total of 43 eyes in 43 patients were reviewed. The IOP 15 min after ACP (23.3 ± 9.6 mmHg) and 24 h after ACP (21.6 ± 12.0 mmHg) were significantly lower than that before ACP (58.6 ± 12.9 mmHg). The IOP 15 min after ACP was significantly lower than the IOP 15 min after conventional treatment (55.4 ± 10.3 mmHg). Visual acuity recovery was achieved earlier after ACP than after conventional treatment. Hyphema after ACP was noted in one eye. The mean pH of the aqueous humor in APAC was 6.99 ± 0.35. The pH of the aqueous humor significantly correlated with the duration of acute IOP elevation and the IOP before ACP. Conclusions: ACP is an effective and safe procedure. The pH of aqueous humor is lower in eyes with APAC of longer duration and in eyes with higher IOP at presentation. [ABSTRACT FROM AUTHOR]

Abstract: Induced pluripotent stem cells (iPSCs) have promising potential in regenerative medicine, but whether iPSCs can promote corneal reconstruction remains undetermined. In this study, we successfully reprogrammed human corneal keratocytes into iPSCs. To prevent feeder cell contamination, these iPSCs were cultured onto a serum- and feeder-free system in which they remained stable through 30 passages and showed ESC-like pluripotent property. To investigate the availability of iPSCs as bioengineered substitutes in corneal repair, we developed a thermo-gelling injectable amphiphatic carboxymethyl-hexanoyl chitosan (CHC) nanoscale hydrogel and found that such gel increased the viability and CD44 + proportion of iPSCs, and maintained their stem-cell like gene expression, in the presence of culture media. Combined treatment of iPSC with CHC hydrogel (iPSC/CHC hydrogel) facilitated wound healing in surgical abrasion-injured corneas. In severe corneal damage induced by alkaline, iPSC/CHC hydrogel enhanced corneal reconstruction by downregulating oxidative stress and recruiting endogenous epithelial cells to restore corneal epithelial thickness. Therefore, we demonstrated that these human keratocyte-reprogrammed iPSCs, when combined with CHC hydrogel, can be used as a rapid delivery system to efficiently enhance corneal wound healing. In addition, iPSCs reprogrammed from corneal surgical residues may serve as an alternative cell source for personalized therapies for human corneal damage. [Copyright &y& Elsevier]

Abstract: Objectives: SHP2 (Src-homology-2 domain-containing protein tyrosine phosphatase) plays an important role in cell adhesion, migration and cell signaling. However, its role in focal adhesion, differentiation and migration of neural stem cells is still unclear. Methods: In this study, rat neurospheres were cultured in suspension and differentiated neural stem cells were cultured on collagen-coated surfaces. Results: The results showed that p-SHP2 co-localized with focal adhesion kinase (FAK) and paxillin in neurospheres and in differentiated neural precursor cells, astrocytes, neurons, and oligodendrocytes. Suppression of SHP2 activity by PTP4 or siRNA-mediated SHP2 silencing caused reduction in the cell migration and neurite outgrowth, and thinning of glial cell processes. Differentiation-induced activation of FAK, Src, paxillin, ERK1/2, and RhoA was decreased by SHP2 inactivation. Conclusions: These results indicate that SHP2 is recruited in focal adhesions of neural stem cells and regulates focal adhesion formation. SHP2-mediated regulation of neural differentiation and migration may be related to formation of focal adhesions and RhoA and ERK1/2 activation. [Copyright &y& Elsevier]

Extraintestinal manifestations are common in patients with inflammatory bowel disease (IBD), and optic neuritis (ON) is a rare but severe one. This study aimed to evaluate possible factors associated with ON in patients with IBD. Adult patients with IBD who were not with concomitant ON on the index date identified from the Taiwan National Health Insurance Research Database (NHIRD) from the years 2000 to 2013 were included. A four-fold matched group was selected using age, sex and year of index date for comparison. All the patients were followed up until the development of ON or the end of the study period. Data of included patients were extracted and analyzed statistically. The mean follow-up time for all patients was 7.13 ± 5.21 years. At the study period conclusion, eight (0.18%) and five (0.003%) patients with and without IBD, respectively, had developed ON (p = 0.001). Adjusted HRs showed that patients with IBD aged between 30 and 39 years, with comorbidities including neuromyelitis optica (NMO), acute disseminated encephalomyelitis (ADEM), systemic lupus erythematosus (SLE) and with a higher Charlson Comorbidity Index, had a significantly higher risk of developing ON (all p < 0.005). Among the eight IBD patients who developed ON, only one patient was diagnosed with Crohn's disease, the male gender was slightly dominant, and two (25%) patients received antitumor necrosis factor α (anti-TNF α) treatment for IBD. Patients with IBD have a higher risk of developing ON compared to patients without IBD. ON occurs more frequently in IBD patients aged between 30 and 39 years, with comorbidities including NMO, ADEM and SLE. Other factors besides anti-TNF α treatment for IBD are more likely associated with the development of ON. [ABSTRACT FROM AUTHOR]

Background: Transforming growth factor (TGF) family members play important roles in the regulation of corneal integrity, and the pathogenesis of corneal fibrosis. Currently, there are no effective agents targeting TGF-β signaling to diminish corneal fibrosis. Glucosamine (GlcN), which is widely used in the treatment of osteoarthritis, abrogates the morphologic effects of TGF-β2 on retinal pigmented epithelial cells in a mouse disease model. Here, we sought to determine whether GlcN would exert beneficial effects against TGF-β1-induced corneal fibrosis. Methods: In human corneal fibroblasts (HCFs) treated with GlcN, the expression of Krüppel-like factor 4 (KLF4) and its downstream signaling effects were determined in the presence and absence of TGF-β1 using immunoblot analysis. We further explored GlcN inhibition of fibroblast-to-myofibroblast differentiation via KLF4 siRNA. The effect of cycloheximide on KLF4 protein levels with or without GlcN administration was assessed to determine whether GlcN affects the stability of the KLF4 protein. Results: In HCFs, GlcN induced the expression of KLF4, which regulated the maturation and maintenance of the ocular surface. GlcN partially suppressed the TGF-β1-induced expression of alpha-smooth muscle actin (α-SMA) and reduced the collagen contraction capacity in HCFs, suggesting a decrease in fibroblast-to-myofibroblast differentiation. This effect appeared to be mediated through suppression of Smad2 phosphorylation and ERK-dependent signaling. The levels of KLF4 mRNA were increased by GlcN and decreased by TGF-β1 and the TGF-β1-induced α-SMA mRNA expression was upregulated when the KLF4 gene was silenced. GlcN also appeared to stabilize the KLF4 protein, reducing its turnover in corneal fibroblasts. Conclusion: These findings shed light on a novel mechanism by which GlcN suppresses TGF-β1-induced fibroblast-to-myofibroblast differentiation through the upregulation of KLF4 expression. Current strategies for treating corneal fibrosis were not effective. Elevating KLF4 levels through the use of GlcN might provide an effective alternative to alleviate the development and progression of corneal fibrosis. [ABSTRACT FROM AUTHOR]