Cellular toxicity profile of a new ophthalmic sponge.

Introduction: Ophthalmic sponges are used for cleaning the eye surface and absorbing fluids during ophthalmic procedures. This study compared the biological safety and stability of a new ophthalmic sponge, Occucell® (OccuTech Inc, Seongnam, Korea), on the human conjunctival epithelial cells with those of preexisting products to evaluate its clinical application.Materials and Methods: The cytotoxicity of four products, Occucell, a new product, Ultracell®, Eyetec-1, and Eyetec-2, on conjunctival epithelial cells, was evaluated using the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) analysis. Additionally, human conjunctival epithelial cells were stained with a Live & Dead marker and observed using a fluorescence microscope. To evaluate the effect of the ophthalmic sponges on the secretion of IL-1ß and TNF-α, cultured conjunctival epithelial cells were treated with 0.5% DMSO eluates of the ophthalmic sponges, and IL-1ß and TNF-α mRNA levels were estimated using real-time polymerase chain reaction assays.Results: Cells treated with Occucell showed comparable viability to those treated with other preexisting products. Conjunctival epithelial cells showed more than 90% viability when treated with the ophthalmic sponge extracts, as determined by the MTT assay. No significant differences in the number of live & dead cells were observed between the control and treatment groups. Cells treated with all four ophthalmic sponge eluates showed similar IL-1ß and TNF-α mRNA levels.Discussion: Occucell, an eye sponge used during ophthalmic surgery in clinical practice, did not affect the viability of conjunctival epithelial cells, and more than 90% of the cells were viable after the treatment. Further, Occucell showed similar effects on IL-1ß and TNF-α secretion as that of other ophthalmic sponges used in the clinic. This suggested that Occucell is a safe product comparable to the preexisting products.

Comparison of a preservative-free nonsteroidal anti-inflammatory drug and preservative-free corticosteroid after uneventful cataract surgery: multicenter, randomized, evaluator-blinded clinical trial.

PURPOSE: To compare the efficacy of nonsteroidal anti-inflammatory drugs (NSAIDs) and steroidal eyedrops for inflammation management after cataract surgery using slitlamp indicators. SETTING: 11 eye centers in South Korea. DESIGN: Randomized prospective multicenter study with a blinded evaluator. METHOD: In 125 (250 eyes) patients who underwent cataract surgery, bromfenac sodium hydrate 0.1% (NSAID group) was applied twice a day in 1 eye, whereas the other eye was treated with fluorometholone 0.1% (steroid group), 4 times a day for 4 weeks postoperatively. The primary efficacy outcome was the presence of anterior chamber cells and flare at 1 week postoperatively. Anterior chamber cells and flare at 4 to 8 weeks, corrected distance visual acuity, central corneal thickness, conjunctival hyperemia, dry eye parameters, foveal thickness, and ocular and visual discomfort were evaluated as secondary outcomes. RESULTS: At week 1, residual anterior chamber inflammation was not statistically significantly different between the groups (-1.03 ± 1.27 vs -0.95 ± 1.24, P = .4850). However, the NSAID group recovered from conjunctival hyperemia more rapidly than the steroid group (0.30 ± 0.52 vs 0.44 ± 0.81, P = .0144 at week 1). The increase in central corneal thickness in the NSAID group was less than that in the steroid group 1 week postoperatively (7.87 ± 22.46 vs 29.47 ± 46.60 µm, P < .0001). The change in foveal thickness in the NSAID group was significantly less than that in the steroid group (18.11 ± 68.19 vs 22.25 ± 42.37 µm, P = .0002). Lower levels of postoperative ocular and visual discomfort were reported in the NSAID group than in the steroid group under treatment. CONCLUSIONS: Preservative-free bromfenac was as effective as preservative-free fluorometholone eyedrops in anterior chamber inflammation control and showed better signs and symptoms after cataract surgery.

New Biodegradable Drug Delivery System for Patients with Dry Eye.

PURPOSE: This study aimed to develop a new type of drug delivery system (DDS) for treatment of dry eye. METHODS: A new lens-type biodegradable DDS was manufactured using gelatin methacryloly, antibiotics, and conjunctival epithelial cells as bio-inks in a Bio X 3D Bioprinter. Gelatin methacryloly was used as a base, and the conditions were analyzed to maintain the overall shape by using a mixture of 0.1%, 0.15%, and 0.3% hyaluronic acid. In addition, an experiment was conducted to measure the appropriate concentration by evaluating its cytotoxicity according to the concentration of antibiotics mixed therein to prevent infection. The degree of degradation according to the storage temperature and post-processing of the new lens-type biodegradable DDS was measured. RESULTS: Optimal conditions were maintained when using a nozzle pressure of 80 kPa and speed of 4 mm/sec, nozzle pressure of 50 kPa and speed of 3 mm/sec, nozzle pressure of 60 kPa and speed of 8 mm/sec for 0.1%, 0.15%, and 0.3% hyaluronic acid concentrations, respectively. Degradation did not occur at 4°C and all the lenses were degraded at 37°C within 24 hours. In addition, the degradation rate was delayed according to the ultraviolet crosslink treatment time. Tobramycin 1% was used as an antibiotic during manufacture. CONCLUSIONS: A new lens-type biodegradable DDS that can control the degree of degradation was designed using a 3-dimentional bioprinter. This DDS will contribute to ease of treatment, protection of the cornea, and regeneration of the epithelium in patients with dry eye.

Clinical Features and Management of Stenotrophomonas Maltophilia Keratitis.

INTRODUCTION: Stenotrophomonas maltophilia keratitis is an uncommon infectious disease of the cornea. The clinical features, antibiotic susceptibility, and clinical outcomes of S. maltophilia keratitis were investigated in this study. METHODS: Between January 2015 and February 2020, the medical records of 16 patients with culture-proven S. maltophilia-associated infectious keratitis were retrospectively reviewed. Clinical data were analyzed regarding risk factors, clinical presentation, antibiotic susceptibility, and clinical outcomes. RESULTS: The average age of the patients was 56.24 ± 24.84 years. The most common risk factors for S. maltophilia keratitis were trauma (6/16, 37.5%), use of contact lenses (6/16, 37.5%), and herpes simplex virus keratitis (3/16, 18.8%), which caused ocular instability. Regarding the antibiotic sensitivities, most isolates (15/16, 93.8%) were susceptible to fluoroquinolones, 87.5% (14/16) of them to aminoglycosides, and 81.3% (13/16) of them to beta-lactams. Patients were classified into two groups according to the initial antibiotic eye drops, and there were significant differences in the final visual acuity between two groups: mixed fluoroquinolone, beta-lactam, aminoglycoside group, and mixed beta-lactam and aminoglycoside groups (p = 0.039). CONCLUSION: Ocular infection due to S. maltophilia is an opportunistic infection followed by instability of the ocular surface. In cases of S. maltophilia infection, mixed use of fluoroquinolone, beta-lactam, and aminoglycoside should be considered for treatment of choice.

Reactive oxygen species-sensitive nanophotosensitizers of aminophenyl boronic acid pinacol ester conjugated chitosan-g-methoxy poly(ethylene glycol) copolymer for photodynamic treatment of cancer.

The aim of this study is to prepare reactive oxygen species (ROS)-sensitive nanophotosensitizers for targeted delivery of chlorin e6 (Ce6) and photodynamic tumor therapy. For this purpose, thiodipropionic acid (TDPA) was conjugated with phenyl boronic acid pinacol ester (PBAP) (TDPA-PBAP conjugates) and then the TDPA-PBAP conjugates were attached to the chitosan backbone of chitosan-g-methoxy poly(ethylene glycol) (ChitoPEG) copolymer (ChitoPEG-PBAP). Ce6-incorporated ChitoPEG-PBAP nanophotosensitizers have an ROS-sensitive manner in vitro. The size of ChitoPEG-PBAP nanoparticles increased or disintegrated in a responsive manner against H2O2 concentration. The Ce6 release rate from ChitoPEG-PBAP nanophotosensitizers also increased by adding H2O2. These results indicated that nanophotosensitizers have sensitivity against ROS and showed triggered Ce6 release behavior. ChitoPEG-PBAP nanophotosensitizers can be more efficiently internalized into cancer cells compared to Ce6 alone and then produce ROS in a more efficient manner. Furthermore, ChitoPEG-PBAP nanophotosensitizers suppressed the viability of cancer cells in vitro and tumor growth in vivo with higher efficacy compared to Ce6 alone. Furthermore, ChitoPEG-PBAP nanophotosensitizers were efficiently delivered to irradiated tumor tissues, indicating that ChitoPEG-PBAP nanophotosensitizers can be delivered to the tumor with ROS-sensitive manner. We suggest that a ChitoPEG-PBAP nanophotosensitizer is a promising candidate for photodynamic therapy of cancers.

Conjugation of Cell-Penetrating Peptides to Antimicrobial Peptides Enhances Antibacterial Activity.

Antimicrobial peptides (AMPs), essential elements in host innate immune defenses against numerous pathogens, have received considerable attention as potential alternatives to conventional antibiotics. Most AMPs exert broad-spectrum antimicrobial activity through depolarization and permeabilization of the bacterial cytoplasmic membrane. Here, we introduce a new approach for enhancing the antibiotic activity of AMPs by conjugation of a cationic cell-penetrating peptide (CPP). Interestingly, CPP-conjugated AMPs elicited only a 2- to 4-fold increase in antimicrobial activity against Gram-positive bacteria, but showed a 4- to 16-fold increase in antimicrobial activity against Gram-negative bacteria. Although CPP-AMP conjugates did not significantly increase membrane permeability, they efficiently translocated across a lipid bilayer. Indeed, confocal microscopy showed that, while AMPs were localized mainly in the membrane of Escherichia coli, the conjugates readily penetrated bacterial cells. In addition, the conjugates exhibited a higher affinity for DNA than unconjugated AMPs. Collectively, we demonstrate that CPP-AMP conjugates possess multiple functional properties, including membrane permeabilization, membrane translocation, and DNA binding, which are involved in their enhanced antibacterial activity against Gram-negative bacteria. We propose that conjugation of CPPs to AMPs may present an effective approach for the development of novel antimicrobials against Gram-negative bacteria.

Choroidal Blood Flow Change in Eyes with High Myopia.

PURPOSE: To evaluate choroidal blood flow changes in eyes with high myopia according to the pulsatile components of ocular blood flow analysis. METHODS: A total of 104 subjects (52 males and 52 females) were included in this study. One eye of each participant was randomly selected and assigned to one of four refractive groups, designated as, hyperopes (n = 20; refractive error, ≥+1.00 diopter [D]), emmetropes (n = 28; refractive error, ±0.75 D), lower myopes (n = 33; refractive error, -1.00 to -4.75 D), and high myopes (n = 23; refractive error, ≤-5.00 D). Components of pulse amplitude (OBFa), pulse volume (OBFv), pulse rate (OBFr), and pulsatile ocular blood flow (POBF) were analyzed using a blood flow analyzer. Intraocular pressure and axial length were measured. RESULTS: Pulsatile components of OBFa, OBFv, and POBF showed positive correlations with refractive error and showed negative correlations with axial length (r = 0.729, r = 0.772, r = 0.781, respectively, all p < 0.001; r = -0.727, r = -0.762, r = -0.771, respectively, all p < 0.001). The correlations of refractive error and axial length with OBFr were irrelevant (r = -0.157, p = 0.113; r = 0.123, p = 0.213). High myopes showed significantly lower OBFa, OBFv, and POBF than the other groups (all p < 0.001). CONCLUSIONS: Axial length changes in high myopes potentially influence choroidal blood flow, assuming the changes are caused by narrowing of the choroidal vessel diameter and increasing rigidity of the choroidal vessel wall. These finding explains the influence of axial length on OBFa, OBFv, and POBF, but not on OBFr. Thus, changes in axial length and the possible influence of these changes on the physical properties of choroidal vessels is the mechanism believed to be responsible for putting high myopes at risk for ocular vascular diseases.

Association Between Platelet Function and Disc Hemorrhage in Patients With Normal-Tension Glaucoma: A Prospective Cross-Sectional Study.

PURPOSE: To evaluate the association between platelet function and disc hemorrhage in patients with normal-tension glaucoma. DESIGN: Prospective, cross-sectional study. METHODS: Study involved a total of 315 subjects, including patients with normal-tension glaucoma and disc hemorrhage (n = 120), patients with normal-tension glaucoma without disc hemorrhage (n = 75), and healthy individuals (control group, n = 120). A detailed eye examination including visual field testing, color disc photography, optical coherence tomography scanning, and measurement of collagen/epinephrine closure time using a platelet function analyzer were performed for all subjects. RESULTS: The collagen/epinephrine closure time (s) as measured by the platelet function analyzer was approximately 14%-24% longer in the normal-tension glaucoma and disc hemorrhage group compared with the other groups (141.92 ± 53.44 [with normal-tension glaucoma and disc hemorrhage] vs 124.60 ± 46.72 [with normal-tension glaucoma without disc hemorrhage] vs 114.84 ± 34.84 [healthy individuals], 1-way analysis of variance test, P < .001). The activated partial thromboplastin time (s) value of the normal-tension glaucoma with disc hemorrhage group was also higher than the control group. Stepwise multiple logistic regression analysis revealed that only a longer collagen/epinephrine closure time (OR adjusted for age, sex, prothrombin time, activated partial thromboplastin time, diabetes mellitus, hypertension, hypotension, heart disease, hypothyroidism, migraine, stroke, hypercholesterolemia: 2.94; 95% CI: 1.40-6.17) was independently associated with disc hemorrhage. A similar trend was observed when platelet function was compared among the 3 groups with respect to age. CONCLUSIONS: Our results suggest that platelet function is significantly associated with disc hemorrhage in patients with normal-tension glaucoma. Delayed absorption resulted from prolonged bleeding due to delayed platelet aggregation may have an effect on the detectability of disc hemorrhage in patients with normal-tension glaucoma.

Prognostic value of timing of antibiotic administration in patients with septic shock treated with early quantitative resuscitation.

BACKGROUND: The Surviving Sepsis Campaign recommends initiating broad-spectrum antibiotic treatment within 1 hour of septic shock recognition. However, there is controversy regarding this owing to contradictory studies. This study investigated the relationship between the antibiotic administration interval and 28-day mortality in septic shock patients treated with an early quantitative resuscitation protocol in an emergency department (ED). METHODS: 715 consecutive septic shock patients were prospectively collected from January 2010 to December 2012. Of these, 426 patients developed shock at or after initial assessment, and the time of initial antibiotic administration was recorded. The primary outcome was 28-day mortality. RESULTS: The median antibiotic administration interval was 91.5 (47.0-158.0) minutes, and the 28-day mortality was 20.0%. Mortality did not change with hourly delays in antibiotic administration up to 5 hours after shock recognition: 1 hour (odds ratio [OR]: 0.81, 95% confidence interval [CI]: 0.45-1.45), 2 hours (OR: 0.72, 95% CI: 0.40-1.29) and 3 hours (OR: 0.61, 95% CI: 0.30-1.25). However, inability to achieve early resuscitation goals (OR: 1.94, 95% CI: 1.07-3.51), sequential organ failure assessment score (OR: 1.30, 95% CI: 1.17-1.44) and lactic acid concentration (OR: 1.66, 95% CI: 1.11-2.49) were significantly associated with an increased risk of 28-day mortality. CONCLUSIONS: Among septic shock patients who underwent early quantitative resuscitation in an ED, mortality did not increase with hourly delays in antibiotic administration. These data call into question the strength of the association between hourly delays in antibiotic administration and mortality in septic shock patients.

Comparative quantification of plasma TDRD7 mRNA in cataract patients by real-time polymerase chain reaction.

PURPOSE: To investigate the relationship between plasma TDRD7 mRNA and lens transparency, and to evaluate plasma TDRD7 mRNA as a potential marker for cataracts and its sub-type by quantitatively analyzing human peripheral blood. METHODS: Plasma RNA was extracted from 40 patients with cataracts, and 30 normal controls of matched age and gender. Blood cholesterol and fasting glucose were measured, and the RNA extracted from the sample was synthesized into cDNA. After polymerase chain reaction, the results were compared after quantifying the TDRD7 mRNA using ABL1 mRNA for normalization. We analyzed the relative gene expression data via the ΔΔCt method. RESULTS: The normalized 2(-ΔΔCt) of plasma TDRD7 mRNA based on ABL1 mRNA was 1.52 ± 0.63 in the case of the control group and 1.05 ± 0.34 in the case of the cataract patients, and the TDRD7 expression level of the cataract patients was lower than that of the control group (p = 0.048). The comparison of the genetic values of different types of cataracts demonstrated that the TDRD7 expression level of the cortical type and mixed type were lower than those of the nuclear type and posterior subcapsular opacity type (p = 0.017). CONCLUSIONS: Human cataracts and the TDRD7 gene loss-of-function mutations are strongly causally related, as the expression level of plasma TDRD7 mRNA in patients with cataracts was statistically significantly lower than in the normal control group.

Sleep deprivation reduces tear secretion and impairs the tear film.

PURPOSE: We investigated whether sleep deprivation (SD) disturbs the tear film. METHODS: A total of 20 healthy male subjects with no ocular disease was recruited: 10 were allocated to the SD group and 10 to the control group The 10 subjects in the SD group were deprived of sleep in an experimental setting and their outcomes were compared to those of the control group, which was not sleep-deprived. Tear film and ocular surface were evaluated at 2 PM, 10 PM, and 6 AM and 2 PM the following day. Tear osmolarity, Schirmer's test, tear film break-up time (TBUT), pain on a visual analog scale (VAS), and IOP were measured. RESULTS: At 6 AM the following day, mean tear osmolarity level increased (P = 0.004), TBUT was significantly shorter (P = 0.01), and tear secretion measured by Schirmer's test was significantly reduced in the SD group than in the control group (P = 0.004). No significant change in IOP was observed in either group. CONCLUSIONS: Sleep deprivation induced tear hyperosmolarity, shortened TBUT, and reduced tear secretion, all of which can trigger the development of ocular surface diseases. Therefore, SD can exacerbate signs and symptoms in patients with ocular surface diseases. (ClinicalTrials.gov number, NCT02026986.).

Keratitis with Elizabethkingia meningoseptica occurring after contact lens wear: a case report.

To report keratitis with Elizabethkingia meningoseptica, which occurred in a healthy patient after wearing contact lenses for 6 months. A 24-year-old male patient visited our hospital with ocular pain. This patient had a history of wearing soft contact lenses for 6 months, about 10 hours per day. At initial presentation, slit lamp examination showed corneal stromal infiltrations and small epithelial defect. Microbiological examinations were performed from corneal scrapings, contact lenses, and the contact lens case and solution. The culture results from contact lenses, contact lens case and solution were all positive for Elizabethkingia meningoseptica. Thus, we could confirm that the direct cause of keratitis was contamination of the contact lenses. The patient was treated with 0.3% gatifloxacin. After treatment, the corneal epithelial defect was completely healed, and a slight residual subepithelial corneal opacity was observed. We diagnosed keratitis with Elizabethkingia meningoseptica in a healthy young male wearing soft contact lenses. We conclude that Elizabethkingia meningoseptica should be considered as a rare but potential pathogen for lens-related keratitis in a healthy host.

Cytotoxicity of ganciclovir on cultured human corneal endothelial cells.

BACKGROUND: Intraocular cytomegalovirus (CMV) infections, including endotheliitis and retinitis, have been reported to threaten the host's vision. These infections have been treated with systemic or intravitreal GCV injection. Intracameral GCV injection can be an effective treatment option that avoids systemic side effects. The cytotoxic effect of ganciclovir (GCV) on cultured human corneal endothelial cells (HCECs) was evaluated. METHODS: HCECs were cultured and exposed to various concentrations (0-20 mg/ml) of GCV (Cytovene(®)). Cell viability was assessed by the Cell Counting Kit-8 method and live/dead viability/cytotoxicity assays. Cell morphology was assessed using phase-contrast microscopy after 48 h exposure to GCV. Cell cycle and apoptosis were analysed using NC-3000 to evaluate the effect of GCV on HCECs. The cell proliferation rate was evaluated by a bromodeoxyuridine proliferation assay. RESULTS: Cytotoxicity tests showed that GCV had a dose-dependent cytotoxic effect on HCECs. GCV concentrations of ≥5 mg/ml resulted in a significant reduction in cell viability. Higher concentrations of GCV resulted in cell cycle delay, low proliferation rate, and an increased number of apoptotic cells, indicating activation of the pro-apoptotic pathway. CONCLUSIONS: Our results suggest that intracameral GCV concentrations of ≥5 mg/ml may increase the risk of corneal endothelial damage, although GCV concentrations of ≤0.5 mg/ml do not decrease cell viability.

Effects of cadmium chloride on the cultured human lens epithelial cells.

PURPOSE: To investigate cadmium chloride cytotoxicity in human lens epithelial cells as well as the mode of cell death and its mechanism. METHODS: Cultured human lens epithelial cells were challenged with cadmium chloride. Morphological changes of human lens epithelial cells caused by cadmium chloride exposure were evaluated by microscope. Cell viability was evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-dipheny tetrazolium bromice (MTT) assay. To explore the mechanism of cell death, p53 and caspase-8 levels were measured by western blotting. RESULTS: Microscopic examination indicated that cell death increased after cadmium chloride exposure compared to untreated cells. The MTT assay demonstrated that cadmium chloride significantly decreased cell viability in a dose dependent way. Western blot and quantitative analysis showed that both p53 and caspase-8 increased after cell exposure to cadmium chloride. p53 increased 210% and caspase-8 increased 30% in the experimental group as compared with the control group. CONCLUSIONS: Cadmium chloride induced cytotoxicity and apoptosis in human lens epithelial cells and the mechanism of apoptosis involve an increased expression of p53 and caspase-8.

Achromobacter xylosoxidans keratitis after contact lens usage.

To report on Achromobacter xylosoxidans keratitis in two healthy patients who had worn contact lenses foran extended period of time. A 36-year-old female and a 21-year-old female visited our hospital with ocular pain and blurred vision. Both patients had a history of wearing soft contact lenses for over fve years with occasional overnight wear. At the initial presentation, a slit lamp examination revealed corneal stromal infiltrations and epithelial defects with peripheral neovascularization in both patients. Microbiological examinations were performed from samples of corneal scrapings, contact lenses, contact lens cases, and solution. The culture resulting from the samples taken from the contact lenses, contact lens cases, and solution were all positive for Achromobacter xylosoxidans. Confrming that the direct cause of the keratitis was the contact lenses, the frst patient was prescribed ceftazidime and amikacin drops sensitive to Achromobacter xylosoxidans. The second patient was treated with 0.3% gatifoxacin and fortifed tobramycin drops. After treatment, the corneal epithelial defects were completely healed, and subepithelial corneal opacity was observed. Two cases of Achromobacter xylosoxidans keratitis were reported in healthy young females who wore soft contact lenses. Achromobacter xylosoxidans should be considered a rare but potentially harmful pathogen for lens-induced keratitis in healthy hosts.

Optimal insertion depth of central venous catheters--is a formula required? A prospective cohort study.

INTRODUCTION: To determine the optimal length for initial insertion of central venous catheters (CVCs) and to evaluate whether a recommended depth predicted optimal positioning of CVCs. MATERIALS AND METHODS: All patients who were CVC-cannulated and who underwent chest computed tomography (CT) during a 10-month period were included. We measured the distance from catheter insertion to the superior vena cava/right atrium (SVC/RA) junction and calculated a recommended insertion depth. We compared the accuracy of the recommended depth with that suggested by the formula of Peres for predicting optimal positioning of a CVC. RESULTS: Of the 1238 patients who were CVC-cannulated over 10 months, 106 underwent chest CT. Based on the mean distance from the CVC insertion point to the distal SVC, we determined that the recommended depth of insertion should be 14 cm for the right subclavian vein, 15 cm for the right internal jugular vein, 17 cm for the left subclavian vein and 18 cm for left internal jugular vein. Using these guidelines, initial placement of a CVC in the distal SVC was more accurate than when the Peres formula was used (91.5% vs. 77.4%, p<0.05). CONCLUSIONS: For Asian populations, we found that these guidelines are more accurate than those derived from the Peres formulae and more simple to use, thus increasing the likelihood of optimal tip location within the SVC on the first attempt and eliminating the need for later repositioning.

Combined treatment with antioxidants and immunosuppressants on cytokine release by human peripheral blood mononuclear cells - chemically injured keratocyte reaction.

PURPOSE: To investigate the effect of antioxidants and immunosuppresants on mixed peripheral blood mononuclear cells (PBMC) - chemically injured keratocytes reaction (MLKR). METHODS: The PBMC stimulation assay was performed using chemically injured keratocytes treated with 0.05 N NaOH for 90 s (MLKR). MLKR were treated with various drugs including rapamycin, dexamethasone, mycophenoleic acid (MPA), alpha lipoic acid (ALA), and N-acetyl cysteine (NAC). Matrix metalloprotease-9 (MMP-9), transforming growth factor-beta 1 (TGF-ß1), interleukin-6 (IL-6), and macrophage migration inhibitory factor (MIF) secretion profiles of activated PBMCs stimulated by NaOH-treated keratocytes were determined by ELISA. RESULTS: Anti-oxidants as well as immunosuppressants suppressed PBMC proliferation. MMP-9 levels were lower in antioxidants group. IL-6 levels decreased in dexamethasone group and anti-oxidants group. Combination of immunosuppressants and antioxidants suppressed more PBMC proliferation except for rapamycin + ALA group, suppressed MMP-9 production except for MPA + ALA group, decreased IL-6 levels and increased MIF levels except for rapamycin + ALA group. TGF-ß1 levels were elevated in rapamycin group and rapamycin + ALA group. CONCLUSIONS: Cytokine production was different depending on combination of drugs.Our results suggest that the different drugs should be selected for treatment according to the phases of corneal chemical burn.

Mechanisms of apoptosis on human lens epithelium after ultraviolet light exposure.

PURPOSE: The purpose of this study is to understand the mechanism of apoptosis occurring on a cultured human lens epithelial cell line after exposure to ultraviolet (UV) light. We intended to confirm the presence of cellular toxicity and apoptosis and to reveal the roles of p53, caspase 3 and NOXA in these processes. METHODS: Cells were irradiated with an ultraviolet lamp. Cellular toxicity was measured by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Hoechst staining and fluorescent anti-caspase 3 antibodies were used for apoptosis investigation. The quantities of p53, caspase 3, and NOXA were measured by Western blotting for to investigate the apoptosis pathway. RESULTS: Cellular toxicity on the human lens epithelium markedly increased with time after UV exposure. On Hoechst staining, we found that apoptosis also remarkably increased after exposure to ultraviolet light, compared with a control group. In the immunochemical study using anti-caspase 3 antibodies, active caspase 3 significantly increased after exposure to ultraviolet light. On Western blotting, p53 decreased, while caspase 3 and NOXA increased. CONCLUSIONS: Exposure of cultured human lens epithelial cell lines to ultraviolet light induces apoptosis, which promotes the expression of NOXA and caspase 3 increases without increasing p53. This may suggest that UV induced apoptosis is caused by a p53-independent pathway in human lens epithelial cells.

Effects of prostaglandin F2α on small intestinal interstitial cells of Cajal.

AIM: To explore the role of prostaglandin F(2α) (PGF(2α))) on pacemaker activity in interstitial cells of Cajal (ICC) from mouse small intestine. METHODS: In this study, effects of PGF(2α) in the cultured ICC cells were investigated with patch clamp technology combined with Ca(2+) image analysis. RESULTS: Externally applied PGF(2α) (10 µmol/L) produced membrane depolarization in current-clamp mode and increased tonic inward pacemaker currents in voltage-clamp mode. The application of flufenamic acid (a non-selective cation channel inhibitor) or niflumic acid (a Cl(-) channel inhibitor) abolished the generation of pacemaker currents but only flufenamic acid inhibited the PGF(2α)-induced tonic inward currents. In addition, the tonic inward currents induced by PGF(2α) were not inhibited by intracellular application of 5'-[-thio]diphosphate trilithium salt. Pretreatment with Ca(2+) free solution, U-73122, an active phospholipase C inhibitor, and thapsigargin, a Ca(2+)-ATPase inhibitor in endoplasmic reticulum, abolished the generation of pacemaker currents and suppressed the PGF(2α)-induced tonic inward currents. However, chelerythrine or calphostin C, protein kinase C inhibitors, did not block the PGF(2α)-induced effects on pacemaker currents. When recording intracellular Ca(2+) ([Ca(2+)](i)) concentration using fluo-3/AM, PGF(2α) broadly increased the spontaneous [Ca(2+)](i) oscillations. CONCLUSION: These results suggest that PGF(2α) can modulate pacemaker activity of ICC by acting non-selective action channels through phospholipase C-dependent pathway via [Ca(2+)]i regulation.