Molecular Epidemiology of Adenoviral Keratoconjunctivitis in Korea.

Human adenoviruses (HAdVs) are a major cause of epidemic keratoconjunctivitis. We investigated the types of adenoviruses responsible for the recent epidemic of keratoconjunctivitis in Korea. From January to November 2019, 218 conjunctival swab samples were collected from patients clinically suspected as having adenoviral keratoconjunctivitis. Genotyping targeting of adenovirus capsid hexon genes was performed using PCR and sequencing. Of the 218 samples collected, 128 (58.7%) were positive for the adenovirus genes by PCR, and 126 samples were successfully genotyped. Adenovirus type 8 (HAdV-D8) was the most common type (67.5%), followed by HAdV-D64 (11.1%), HAdV-D37 (9.5%), HAdV-B3 (5.6%), HAdV-D53 (4.0%), HAdV-E4 (1.6%), and HAdV-D56 (0.8%). Adenoviral keratoconjunctivitis cases were the most frequent in July and August 2019, which were mainly caused by type 8. Phylogenetic analyses revealed little genetic distance among adenoviruses of the same type detected in our study. Our results provide basic data for further studies of adenoviral keratoconjunctivitis.

Traffic-related particulate matter aggravates ocular allergic inflammation by mediating dendritic cell maturation.

The aim of this study was to determine the effects of traffic-related particulate matter (PM) on allergic inflammation of ocular surfaces. BALB/c mice were sensitized with ovalbumin (OVA) and aluminum hydroxide via intraperitoneal injection. Two weeks later, mice were challenged with eye drops containing OVA concomitant with either traffic-related PM2.5 or vehicle eye drops. Topical OVA challenges were administered following unilateral subconjunctival injection of magnetic-bead-sorted CD11c+ dendritic cells (DC). The following were assessed: (1) clinical signs, (2) infiltration of inflammatory cells into conjunctiva, (3) serum levels of OVA-specific IgE production, and (4) T-cell cytokine secretion with topical application of PM2.5, compared to saline vehicle. PM2.5 was found to increase production of OVA-specific IgE in serum and Th2 immune response-related cytokines including interleukin (IL)-4, IL-17A, and IL-13 compared to vehicle control. It is of interest that PM2.5 treatment also elevated the population of mature DCs in draining lymph nodes (LNs). Exposure with PM2.5 was associated with a significant rise in conjunctival expression of IL-1ß, IL-6, IL-17, and TNF. After subconjunctival injection of CD11c+DCs from PM2.5-treated allergic conjunctivitis (AC) mice into naïve mice, T cell responses and OVA-specific IgE were also enhanced. Data suggest that traffic-related PM2.5 exacerbated allergic conjunctivitis as evidenced by increased infiltration of inflammatory cells into the conjunctiva and Th2 responses in the draining LNs associated with enhanced maturation of DCs. Our findings provide new insight into the hazardous potential of traffic-related PM2.5 on allergic diseases, such as asthma or atopic dermatitis.

Prediction Model for Dry Eye Syndrome Incidence Rate Using Air Pollutants and Meteorological Factors in South Korea: Analysis of Sub-Region Deviations.

Here, we develop a dry eye syndrome (DES) incidence rate prediction model using air pollutants (PM10, NO2, SO2, O3, and CO), meteorological factors (temperature, humidity, and wind speed), population rate, and clinical data for South Korea. The prediction model is well fitted to the incidence rate (R2 = 0.9443 and 0.9388, p < 2.2 × 10-16). To analyze regional deviations, we classify outpatient data, air pollutant, and meteorological factors in 16 administrative districts (seven metropolitan areas and nine states). Our results confirm NO2 and relative humidity are the factors impacting regional deviations in the prediction model.

Exposure to Traffic-Related Particulate Matter 2.5 Triggers Th2-Dominant Ocular Immune Response in a Murine Model.

Ambient particulate matter (PM), a major component of air pollution, aggravates ocular discomfort and inflammation, similarly to dry eye disease (DED) or allergies. However, the mechanism(s) by which PM induces the ocular inflammatory response is unknown. This study investigated the immunological response of traffic-related fine particulate matter (PM2.5) on the ocular surface in a murine model. C57BL/6 mice were exposed by topical application to PM2.5 or vehicle for 14 days to induce experimental environmental ocular disease. Corneal fluorescein staining and the number of ocular inflammatory cells were assessed in both groups. The expression of IL-1ß, IL-6, tumor necrosis factor (TNF)-α, and mucin 5AC (MUC5AC) in the ocular surface were evaluated by real-time PCR. An immunohistochemical assay evaluated apoptosis and goblet cell density. ELISA was used to determine the levels of serum IgE and cytokines of Type 1 helper (Th1) and Type 2 helper (Th2) cells after in vitro stimulation of T cells in the draining lymph nodes (LNs). Exposure to traffic-related PM2.5 significantly increased corneal fluorescein staining and cellular toxicity in the corneal epithelium compared with the vehicle control. A significant increase in the number of CD11b+ cells on the central cornea and mast cells in the conjunctiva was observed in the PM2.5 group. Exposure to PM2.5 was associated with a significant increase in the corneal or conjunctival expression of IL-1ß, IL-6, TNF, and MUC5AC compared to the vehicle, and increased maturation of dendric cells (DCs) (MHC-IIhighCD11c+) in draining LNs. In addition, PM2.5 exposure increased the level of serum IgE and Th2 cytokine production in draining LNs on day 14. In conclusion, exposure to traffic-related PM2.5 caused ocular surface damage and inflammation, which induced DC maturation and the Th2-cell-dominant allergic immune response in draining LNs.

Characteristics of nanoparticle formation and hazardous air pollutants emitted by 3D printer operations: from emission to inhalation.

This study examined the emissions of nanoparticles and hazardous air pollutants (HAPs) by 3D printer operations and evaluated nanoparticle deposition behavior using a prediction model. Nanoparticles and HAPs were sampled at the Inha University 3D printing center with five fused filament fabrication (FFF)-type 3D printers. The number size distribution of the nanoparticles exhibited a bimodal distribution with dominant peaks over a large size range between 70 and 100 nm and a smaller size range between 10 and 20 nm. With increasing 3D printer operation, the number concentration of 10 nm particles increased, and the final number concentration was 3.6 times higher than that of the background concentration. Nanoparticle formation and agglomeration were characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Model calculations revealed that a large number of nanoparticles between 10 and 30 nm in size are deposited in the lower human respiratory tract (generation number: 16-22). A total of 14 HAPs species were detected, among which hexane, acrylonitrile, and benzene concentrations were the highest.

Development of a Conjunctivitis Outpatient Rate Prediction Model Incorporating Ambient Ozone and Meteorological Factors in South Korea.

Ozone (O3) is a commonly known air pollutant that causes adverse health effects. This study developed a multi-level prediction model for conjunctivitis in outpatients due to exposure to O3 by using 3 years of ambient O3 data, meteorological data, and hospital data in Seoul, South Korea. We confirmed that the rate of conjunctivitis in outpatients (conjunctivitis outpatient rate) was highly correlated with O3 (R 2 = 0.49), temperature (R 2 = 0.72), and relative humidity (R 2 = 0.29). A multi-level regression model for the conjunctivitis outpatient rate was well-developed, on the basis of sex and age, by adding statistical factors. This model will contribute to the prediction of conjunctivitis outpatient rate for each sex and age, using O3 and meteorological data.

Tear Dysfunction Syndrome After Burn.

The objective of this study was to evaluate tear dysfunction of burn patients objectively. We retrospectively reviewed medical records of patients who had been examined within 1 week after burn injury. Visual acuity, intraocular pressure, cilia burned state, tear film break-up time (TBUT), and fluorescein corneal staining were evaluated. Sixty-four eyes of 32 patients (man 27, female 5) were included. Mean age was 44.41 ± 12.76 years old. Mean best corrected visual acuity was logMAR 0.04 ± 0.08, mean intraocular pressure was 13.41 ± 3.13 mm Hg, and mean TBUT was 5.48 ± 3.18 seconds. Thirty-four eyes (53.13%) showed burned cilia, 36 eyes (56.25%) showed corneal erosion on fluorescein stating. Intraocular pressure and TBUT were lower in TBSA with burn involved ≥ 10% group than TBSA with burn involved < 10% group (P = .000; P = .058). The percentage of TBSA of burn involved and tear break up time showed statistically significant negative correlations (r = -0.262; P = .037). Many burn patients have discomfort due to tear dysfunction syndrome. Tear dysfunction may be caused by direct injury of eye burn itself and body fluid deficiency. We recommend that when we treat burn patients, we have to pay attention to their symptoms and manage patient's eye symptoms properly such as routine artificial tear lubricant treatment.

Development of a population pharmacokinetic model to describe olmesartan medoxomil/ hydrochlorothiazide (20/12.5 mg) FDC tablet in male healthy South Korean subjects.

AIM: The objective of the present study was to develop population pharmacokinetic models for olmesartan medoxomil and hydrochlorothiazide and to investigate the influence of demographic factors on these population pharmacokinetics. METHODS: Plasma concentrations of olmesartan medoxomil and hydrochlorothiazide were measured in 41 healthy volunteers enrolled in our bioequivalence study by LC-MS/MS following oral administration of an olmesartan medoxomil/hydrochlorothiazide (20/12.5 mg) fixed-dose combination tablet. This data and covariates were subjected to nonlinear mixed-effect modeling analysis using the NONMEM software. Evaluation featured a visual predicted check and bootstrapping. RESULTS: The distributions of olmesartan medoxomil and hydrochlorothiazide were best fitted using a two-compartment model with no lag time and first-order elimination. When analyzing hydrochlorothiazide kinetics, we found that TCHO and CL/F were correlated, while. HB and Ka influenced olmesartan medoxomil modeling. All evaluations indicated that the pharmacokinetic profiles of olmesartan medoxomil and hydrochlorothiazide were adequately described using our PPK model. CONCLUSIONS: This study indicates that demographic factors influence the inter-individual variability in the disposition of the combination drug, and it might be more useful to apply it to the PK of olmesartan medoxomil/hydrochlorothiazide (20/12.5 mg) FDC tablets administered to patients with hypertension. *These two authors contributed equally to this work.

A simple pharmacokinetic model of alendronate developed using plasma concentration and urine excretion data from healthy men.

The study of pharmacokinetics of alendronate has been hampered by difficulties in accurately and reproducibly determining their concentrations in serum and urine. Thus, pharmacokinetic characteristics of alendronate have been described in many reports based on urinary excretion data; and plasma pharmacokinetics and the simultaneous pharmacokinetic models of alendronate in plasma and urine are not available. The aims of this study were to measure alendronate concentration in plasma and excretion in urine concurrently and to develop compartmental pharmacokinetic model using urine data. In open-label, single-dose pharmacokinetic study, 10 healthy male volunteers received oral dose of alendronate (70 mg tablet). Blood and urine alendronate concentrations were determined using validated high-performance liquid chromatography method. Non-compartmental analysis was performed using WinNonlin program (Pharsight Inc., Apex, NC). A one-compartment pharmacokinetic model was applied to describe pharmacokinetics of alendronate. A peak plasma alendronate concentration of 33.10 ± 14.32 ng/mL was attained after 1.00 ± 0.16 h. The cumulative amount of alendronate excreted in urine and peak excretion rate were 731.28 ± 654.57 µg and 314.68 ± 395.43 µg/h, respectively. The model, which included first-order absorption rate for oral dosing, showed good fit to alendronate data obtained from plasma and urine. The absorption rate constant was 2.68 ± 0.95 h(-1). The elimination rate constants Kurine and Knon-ur were 0.005 ± 0.004 h(-1) and 0.42 ± 0.08 h(-1), respectively. The pharmacokinetics of alendronate in plasma and urine of healthy men can be predicted using one-compartment model, and thus the behavior of drug in plasma can be estimated from urinary excretion data.

Inhibition of corneal neovascularization in rats by systemic administration of sorafenib.

PURPOSE: To evaluate the effect of orally administered sorafenib on corneal neovascularization in rat models. METHODS: In male Sprague-Dawley rats, a silver nitrate applicator was placed on the central cornea in both eyes to elicit angiogenesis. Rats were divided into 3 groups, the control group and the 2 sorafenib-treated groups (low dose, 30 mg · kg(-1) · day(-1); high dose, 60 mg · kg(-1) · day(-1)). The area of corneal neovascularization was measured by image analysis. Vascular endothelial growth factor receptor 2 (VEGFR2) messenger RNA expression was measured in rat corneas by reverse transcription-polymerase chain reaction, and the expression of phosphorylated extracellular signal-regulated kinase (ERK) was measured by Western blot analysis 1 week after cauterization. RESULTS: The area of corneal neovascularization was significantly reduced by 44% in the 30 mg · kg(-1) · day(-1) group and by 66% in the 60 mg · kg(-1) · day(-1) group, compared with the control group (P = 0.014 and P < 0.0001). Corneal VEGFR2 messenger RNA expression was higher in the control group than in the sorafenib-treated groups. The expression of phosphorylated ERK in rat corneas was suppressed in the sorafenib-treated groups but not in the control group. CONCLUSIONS: Oral administration of a multikinase inhibitor (sorafenib) significantly reduced the development of experimental corneal neovascularization in a dose-dependent manner. This inhibitory effect is probably related to the suppression of ERK phosphorylation by sorafenib.

A case of Stenotrophomonas maltophilia keratitis effectively treated with moxifloxacin.

A 70-year-old man with a long history of diabetes mellitus presented to our hospital (Department of Ophthalmology, Sahm Yook Medical Center, Seoul, Korea) complaining of severe ocular pain and visual disturbance in his left eye that had started three days prior to admission. A round 3.7 × 5.0 mm dense central stromal infiltrate with an overlying epithelial defect was noted on slit-lamp examination. Following corneal scrapings and culture, topical 0.5% moxifloxacin and 0.5% tobramycin were administered hourly. A few days later, Stenotrophomonas maltophilia was isolated in a bacterial culture from a corneal specimen. According to the results of susceptibility tests, topical 0.5% moxifloxacin was given every hour and 0.5% tobramycin was stopped. The patient's clinical features improved steadily with treatment. The corneal epithelium healed rapidly, and the infiltrate resolved within four weeks of the initiation of treatment. The patient's best corrected visual acuity improved from hand motion to 20 / 25.

Preclinical pharmacokinetics of PDE-310, a novel PDE4 inhibitor.

A novel phosphodiesterase-4 inhibitor, 2-aryl-7(3',4'-dialkoxyphenyl)-pyrazolo[1,5-alpha] pyrimidine (PDE-310), has been synthesized for the treatment of respiratory diseases. We conducted in vitro and in vivo studies to characterize the pharmacokinetics of PDE-310. The high liver microsomal stability and low inhibitory potency against CYP isoforms of PDE-310 suggested a low first-pass effect and high bioavailability. PDE-310 exhibited high Caco-2 cell permeability in the absorptive direction (apparent permeability coefficients, ∼20 × 10(-6) cm/s), with higher transport in the secretory direction, giving efflux ratios of 3.9 and 2.6 at 5 and 10 µM, respectively. In addition, the high efflux ratio and improved absorption on treatment with efflux transporter inhibitors such as verapamil and MK-571 indicated the involvement of P-gp, BCRP and MRP2 in intestinal transport. PDE-310 bound strongly to human plasma proteins, whereas significantly more PDE-310 (27-34%) was free in rat plasma. Following intravenous administration, nonlinear elimination of PDE-310 was observed at the tested dose ranges (K(m), 0.87 µg/mL; V(max), 0.3 mg·h(-1)·kg(-1)). Following oral PDE-310 administration, dose-normalized AUC and T(max) increased significantly in a dose-dependent manner. PDE-310 exhibited high oral bioavailability (>70%) and was distributed well to various tissues except brain and testis.

Intravitreal bevacizumab for treatment of diabetic macular edema.

PURPOSE: To evaluate the effect of intravitreal bevacizumab on visual function and retinal thickness in patients with diabetic macular edema (DME). METHODS: Thirty eyes of twenty-eight patients (mean age, 57.9+/-13.8 years) with DME were included in this study. Complete ophthalmic examination, including determination of best-corrected visual acuity (BCVA), stereoscopic biomicroscopy, and retinal thickness measurement by optical coherence tomography (OCT), was done at baseline and at each follow-up visit. All patients were treated with a 0.05 mL intravitreal injection containing 1.25 mg of bevacizumab. RESULTS: All patients completed 3 months of follow-up with a mean follow-up period of 5.26+/-2.39 months. The mean BCVA at baseline was 0.73+/-0.36 logMAR, which significantly improved to 0.63+/-0.41 (p=0.02), 0.58+/-0.36 (p=0.003), and 0.61+/-0.40 logMAR (p=0.006) at 1 week, 1 month, and 3 months. Final BCVA analysis demonstrated that 15 eyes (50%) remained stable and 12 (40%) improved >or=2 lines on BCVA. The mean central retinal thickness was 498.96+/-123.99 microm at baseline and decreased to 359.06+/-105.97 (p<0.001), 334.40+/-121.76 (p<0.001), 421.40+/-192.76 microm (p=0.035) at 1 week, 1 month, and 3 months. No ocular toxicity or adverse effects were observed. CONCLUSIONS: Intravitreal bevacizumab injection resulted in significant improvement in BCVA and central retinal thickness as early as 1 week after injection in patients with DME, and this beneficial effect persisted for up to 3 months. However, the slight reduction in this improvement at 3 months suggests that repeated bevacizumab injections might be necessary. To evaluate the long-term safety and efficacy, further prospective randomized controlled clinical trials will be needed.

Effects of smoking on the pharmacokinetics and pharmacodynamics of a nicotine patch.

The effect of smoking on the pharmacokinetics and pharmacodynamics of a nicotine transdermal delivery system, administered as a single dose or multiple doses, was examined in smokers (n=12) and nonsmokers (n=12). The study was a two-period, parallel trial. In the first period, a single dose of the Nicotinell TTS 20 patch was administered, followed by a 1-week washout period. Then, in the second period, multiple doses of the Nicotinell TTS 20 patch were administered over 4 days. Regarding the pharmacokinetics of nicotine, the AUC(36 h) and AUC(tau) of smokers were about 20% and 40% greater, respectively, than those of nonsmokers. Significant differences in heart rate were observed between smokers and nonsmokers at 10, 12, 16 and 24 h, and significant differences in systolic blood pressure were seen between smokers and nonsmokers at 12, 30 and 36 h in the single-dose study. With multiple doses, significant differences in systolic and diastolic blood pressures were detected between smokers and nonsmokers only at 72.5 and 82 h. Here, it is demonstrated for the first time that the pharmacokinetic and hemodynamic effects of a nicotine patch are significantly different between smokers and nonsmokers.