We propose an adaptive shadow estimator to detect and eliminate the shadow of a moving object whi... more We propose an adaptive shadow estimator to detect and eliminate the shadow of a moving object while adapting to variation of illumination and the environment in an automatic manner. The proposed method discriminates between the shadow and the moving object by cascading three estimators which use the properties of chromaticity, brightness, and local intensity ratio. In the spatial adjustment step,
To solve the problem due to fast illumination change in a visual surveillance system, we propose ... more To solve the problem due to fast illumination change in a visual surveillance system, we propose a novel moving object detection algorithm for which we develop an illumination change model, a chromaticity difference model, and a brightness ratio model. When fast illumination change occurs, background pixels as well as moving object pixels are detected as foreground pixels. To separate detected foreground pixels into moving object pixels and false foreground pixels, we develop a chromaticity difference model and a brightness ratio model that estimates the intensity difference and intensity ratio of false foreground pixels, respectively. These models are based on the proposed illumination change model. Based on experimental results, the proposed method shows excellent performance under various illumination change conditions while operating in real-time.
To evaluate retinal nerve fiber layer (RNFL) thickness profiles according to the foveal position ... more To evaluate retinal nerve fiber layer (RNFL) thickness profiles according to the foveal position relative to the optic disc in myopia In 164 eyes of 164 healthy myopic subjects, the disc-foveal angle was defined as the angle between a horizontal line through the disc center and the line connecting the fovea and disc center in fundus photographs overlaid on Cirrus-HD optical coherence tomography (OCT) images. The quadrant/clock-hour based peripapillary RNFL thickness and differences between the inferior and superior (I-S) quadrant RNFL thicknesses were measured with OCT. RNFL thickness profiles were determined according to the disc-foveal angle and axial length (AL). As the disc-foveal angle increased (i.e., the fovea becomes more inferior to the optic disc), the superior RNFL decreased significantly (P = 0.003), whereas the inferior RNFL and I-S difference increased (P = 0.010 and P < 0.001, respectively). As the AL increased, the average and temporal RNFLs increased significantly (P = 0.013 and P < 0.001, respectively), and I-S difference was not affected (P = 0.231). The disc-foveal angle was significantly decreased with the distance between the fovea and the optic disc (P = 0.033). In multiple linear regression analysis, the disc-foveal angle was found to be a significant factor related to I-S differences, superior and inferior RNFL (all, P < 0.05) after adjusting for age, disc area, and AL. The intrinsic foveal position relative to the optic disc was an essential determinant of normal RNFL thickness in myopia. In particular, it was associated with the vertical asymmetry of RNFL distribution.
Studies in health technology and informatics, 2014
The inferior alveolar nerve canal is an important nerve canal in the jaw bone, and any damage to ... more The inferior alveolar nerve canal is an important nerve canal in the jaw bone, and any damage to this canal can cause pain or fatal complications. Since such damage can be caused by a wrong surgical procedure or surgery plan, accurate surgery planning is necessary. Cone-beam computed tomography (CBCT) is a three-dimensional medical imaging method that is mainly used in dental treatment; however, identifying the nerve canal is difficult in CBCT images as compared to conventional CT images. This paper proposes a new concept of a panoramic curve for nerve canal detection and a detection algorithm that is usually applied to facial recognition was introduced in this study for the automatic detection of nerve canal in CBCT images.
Osong public health and research perspectives, 2014
It is critical to implement effective multiple countermeasures to mitigate or retain the spread o... more It is critical to implement effective multiple countermeasures to mitigate or retain the spread of pandemic influenza. We propose a mathematical pandemic influenza model to assess the effectiveness of multiple countermeasures implemented in 2009. Age-specific parameters, including the transmission rate, the proportion of asymptomatic individuals, the vaccination rate, the social distancing rate, and the antiviral treatment rate are estimated using the least-square method calibrated to the incidence data. The multiple interventions (intensive vaccination, social distancing, antivrial treatment) were successfully implemented resulting in the dramatic reduction in the total number of incidence. The model output is sensitive to age-specific parameters and this leads to the fact that a more elaborate age group model should be developed and extensive further studies must be followed.
To investigate the long-term results of penetrating keratoplasty (PK) in patients with keratoconu... more To investigate the long-term results of penetrating keratoplasty (PK) in patients with keratoconus (KC) and to evaluate factors that might influence the final visual outcome. We retrospectively reviewed the data of all patients with clinical KC who had undergone PK by a single corneal surgeon in a single center from May 1980 to December 2005. The age of the patients, preoperative best-corrected visual acuity (BCVA), corneal thickness, death to preservation time, and preservation to transplantation time were recorded. Additionally, postoperative complications such as graft rejection, development of glaucoma and specular microscopy were checked during the follow-up. Sixty-nine eyes from 69 patients were finally included. The follow-up period was 8.64±6.13y. Graft rejection occurred in 4 eyes of 69 cases (5.8%), and the time to graft rejection was 2.1±1.3y. A Kaplan-Meier survival analysis showed that the estimated cumulative probability of graft rejection at 6, 13, and 17y after PK were 95.6%, 90.0%, and 78.8%, respectively. When we evaluated factors that might influence final BCVA in eyes, no disparity donor-host trephine size (same graft size) as well as higher spherical equivalent, and average K-value were associated with higher final BCVA. (P=0.006, 0.051, 0.092, and 0.021 in eyes with follow-up <8y; P=0.068, 0.065, and 0.030 in eyes with follow-up ≥8y, respectively). The long-term results of PK in patients with KC were favorable with a high percentage of good BCVA. Less myopic change and low average K-reading, as well as a surgical technique using the same size donor-recipient button may provide better visual outcomes particularly in patients with KC.
Capsular laxity is a main contributing factor in recurrent shoulder instability and is suggested ... more Capsular laxity is a main contributing factor in recurrent shoulder instability and is suggested to be correlated with increased capsular volume. Arthroscopic capsular shift combined with Bankart repair can reduce the capsular volume and reinforce the redundant capsule; however, as the capsuloligamentous structure has viscoelastic properties, it is possible for the shifted and tensioned capsule of the glenohumeral joint to slowly stretch out again over time, resulting in an increase in capsular volume. To analyze changes in capsular volume of the glenohumeral joint over time after arthroscopic Bankart repair and capsular shift, the factors associated with these changes, and their relevance to outcomes. Case series; Level of evidence, 4. Included in this study were 105 patients (mean age, 25.8 ± 8.2 years) who underwent arthroscopic Bankart repair and capsular shift for anterior shoulder instability and computed tomography arthrography (CTA) at 3 months and 1 year postoperatively and whose various functional outcomes were evaluated preoperatively and at the last follow-up (>12 months). Among these patients, 27 also had preoperative CTA. These 27 patients were used to make comparisons between preoperative and 3-month postoperative CTA measurements, and all 105 patients were used for all other comparisons. Two raters measured the separate anterior and posterior capsular volume and cross-sectional area at the 5-o'clock position using 3-dimensional (3D) Slicer software. These measurements were subsequently adjusted for each glenoid size. The changes in capsular volume and cross-sectional area at the 5-o'clock position over time, the factors related to higher change in anterior capsular volume, and their correlation with outcomes were evaluated. Three months postoperatively, the total and anterior capsular volume and anterior cross-sectional area significantly decreased; however, these values increased again at 1 year postoperatively (all P < .01). The inter- and intraobserver reliabilities of the measurements were excellent (interclass correlation coefficient = 0.717-0.945). Female sex, being an elite athlete, and more dislocations before surgery were related to a higher increase in anterior capsular volume at 1 year (all P < .05). Eight patients had redislocation, and 18 exhibited positive apprehension test postoperatively, and these patients showed significantly higher increases in anterior and total capsular volume at 1 year than did those without redislocation or positive apprehension sign (all P < .01). However, with the exception of Rowe score, a higher increase in anterior capsular volume was not related to functional outcome measures. Surgeons should be aware of the re-increase in anterior capsular volume or restretching trait of the anterior capsule over time, even after successful arthroscopic Bankart repair and capsular shift. In this study, women, elite athletes, and those with frequent dislocations were at high risk of capsular restretching. An increase in capsular volume was related to redislocation and positive apprehension sign as well as with Rowe score.
Here we report the discovery of a series of potent hepatitis C virus (HCV) NS5A inhibitors based ... more Here we report the discovery of a series of potent hepatitis C virus (HCV) NS5A inhibitors based on the benzidine prolinamide backbone. Taking a simple synthetic route, we developed a novel inhibitor structure, which allows easy modification, and through optimization of the capping group, we identified compound 6 with highly potent anti-HCV activity. Compound 6 is nontoxic and is anticipated to be an effective HCV drug candidate.
To use swept-source optical coherence tomography (OCT) to image the posterior sclera at the poste... more To use swept-source optical coherence tomography (OCT) to image the posterior sclera at the posterior pole and around the optic nerve head (ONH) and measure the subfoveal scleral thickness and laminar thickness to evaluate the relationship between the measured thicknesses and ocular parameters. Prospective, cross-sectional design. The study included 103 patients with glaucoma and 43 controls with axial lengths more than 26 mm. Swept-source OCT images were obtained to capture the subfoveal and ONH regions. Subfoveal scleral thickness and laminar thickness were measured from obtained B-scan images. To verify the reproducibility of the measurement, intraclass correlation coefficients were calculated from selected B-scans. Scleral and laminar thicknesses in patients with normal-tension glaucoma (NTG) was compared with that in patients with primary open-angle glaucoma (POAG). A Pearson correlation was calculated to assess the relationships of scleral and laminar thicknesses with ocular parameters. Posterior scleral thickness could be measured in 68.4% of patients, and laminar thickness could be measured in 88.6% by using swept-source OCT. Interobserver and intraobserver measurement reproducibility was moderate to excellent. The subfoveal scleral thickness was 670.84 ± 160.60 μm in the POAG group and 496.55 ± 115.20 μm in the NTG group; a significant difference between the groups was observed. Subfoveal scleral thickness (r = -0.677, P < 0.001) was negatively correlated with axial length only in patients with NTG, not in patients with POAG. Swept-source OCT detected differences in the thicknesses of the posterior sclera between eyes with NTG and eyes with POAG. Subfoveal scleral thickness was negatively correlated with axial length only in eyes with NTG.
Investigative ophthalmology & visual science, Jan 30, 2014
To assess the relationship between serum level of 25-hydroxyvitamin D (25(OH)D) and refractive er... more To assess the relationship between serum level of 25-hydroxyvitamin D (25(OH)D) and refractive error in Korean adolescents. A total of 2038 adolescent aged 13 to 18 years, who participated in the Korea National Health and Nutrition Examination Survey (KNHANES) from 2008 to 2011 underwent refractive examination using an autorefractor. Serum 25(OH)D concentration and other potential risk factors were examined. Multivariate regression analysis was performed to investigate the association between serum 25(OH)D and spherical equivalent (SE). Among the participants, 80.1% had myopia (-0.5 diopters [D] or more myopic) and 8.9% had high myopia (-6.0 D or more myopia). Age, total energy/Ca intake, area of residence, parental income, and smoking experience were significantly different among groups according to SE (All, P < 0.05). The age-adjusted distribution of SE according to serum 25(OH)D concentration showed a positive relationship (r = 0.067, P = 0.012). The myopia group had a significant positive relationship between SE and serum 25(OH)D tertile concentration (P = 0.020), whereas the nonmyopia group did not have any significant relationship (P = 0.599). In multiple linear regression analyses, SE was significantly associated with low serum 25(OH)D concentration after adjustment for area of residence, parental income, total energy intake, dietary Ca intake, milk consumption, and smoking experience (P = 0.047). The prevalence of high myopia was significantly associated with the lowest tertile of serum 25(OH)D concentration after adjustment for the confounding factors (P = 0.017). Low serum 25(OH)D concentration was associated with myopia prevalence in Korean adolescents. This relationship was particularly notable in adolescents with high myopia.
Atopic dermatitis (AD) is a chronic inflammatory skin disease with biphasic T cell-mediated abnor... more Atopic dermatitis (AD) is a chronic inflammatory skin disease with biphasic T cell-mediated abnormalities. Staphylococcal superantigens contribute to the exacerbation of inflammation in AD. The underlying immunopathological mechanisms are not fully understood. To determine whether epicutaneous application of recombinant staphylococcal enterotoxin A (rSEA) would exacerbate AD-like allergic inflammation induced by 2, 4-dinitrochlorobenzene (DNCB) and house dust mite extract (Dermatophagoides farinae extract, DFE) in a murine model. We first established an AD-like model using BALB/c mice exposed to DNCB/DFE on the ear. Next, Staphylococcus (S.) aureus or rSEA were topically applied to the mice. We evaluated the clinical and histopathological features of the animals. Serum immunoglobulin levels were also measured. In addition, real-time PCR analysis of cytokines produced by T cell subsets in the ears was conducted. Mice treated with S. aureus and rSEA had more severe clinical symptoms, including increased mean dermatitis scores and ear thickness, compared to animals with only AD-like lesions. Total IgE, IgG2a and serum histamine levels were increased in all groups except the normal control group. The S. aureus- and rSEA-treated groups showed increased levels of cytokines such as IL-4, IL-13, INF-γ, IL-17, and IL-18. In particular, increased cytokine expression was more conspicuous in the rSEA-treated group than in mice exposed to S. aureus. The results of this study showed that topical exposure to rSEA as well as SEA-producing S. aureus aggravate atopic skin inflammation. This may be associated with the induction of a mixed Th1/Th2 type dermatitis.
To determine the impact of β-1,3-glucan isolated from Euglena gracilis on corneal epithelial cell... more To determine the impact of β-1,3-glucan isolated from Euglena gracilis on corneal epithelial cell migration and on wound healing in a rat alkali burn model. Immortalized human corneal epithelial cells (HCECs) were cultured in media with 50, 100 and 200 μg/mL laminarin (β-1,3- and β-1,6-glucans), β-1,3-glucan and hyaluronic acid (HA)-conjugated β-1,3-glucan; Dulbecco's modified Eagle's medium (DMEM)/nutrient mixture F-12 (negative control) and serum containing DMEM/nutrient mixture F-12 (positive control). Migration assays were conducted via the manual scraping of HCECs. Next, alkali injuries were induced using 1 N NaOH in 40 eyes of 40 Sprague-Dawley male rats. The injury-only group (n = 10) received topical phosphate-buffered saline four times a day for 2 d. The study groups received 200 μg/mL topical laminarin (n = 10), β-1,3-glucan (n = 10) and β-1,3-glucan HA (n = 10). Using slit-lamp biomicroscopy, injured corneas were evaluated in terms of re-epithelialization and opacity, and tissue sections were histologically analyzed. Migration assay rates were enhanced as laminarin and β-1,3-glucan increased, compared to negative control cells (all p < 0.05). In the comparison between β-1,3-glucan and its HA conjugate form, β-1,3-glucan-HA showed more enhanced migration rate than β-1,3-glucan (p < 0.05). In rat alkali burn model, wound-healing ratio was greatest in β-1,3-glucan-HA groups (96.0 ± 4.1%), followed by β-1,3-glucan (86.0 ± 6.5%), laminarin (67.0 ± 7.5%) and injury-only group (54.0 ± 6.5%) (p < 0.0001; ANOVA). The opacity score was also lowest in β-1,3-glucan-HA groups (3.0 ± 0.75), followed by β-1,3-glucan (3.4 ± 0.5), laminarin (3.7 ± 0.8) and injury-only group (4.7 ± 0.46) (p < 0.0001; ANOVA) Histologically, relatively fewer polymorphonuclear leukocytes infiltrated the corneal stroma in the β-1,3-glucan and β-1,3-glucan-HA groups, compared to the injury-only group. β-1,3-Glucan, particularly when conjugated with HA, promoted epithelial wound healing in vitro and suppressed the acute inflammatory reaction in corneal alkali burns.
To define the diagnostic precision of the Humphrey Matrix 24-2 test and to determine a clinically... more To define the diagnostic precision of the Humphrey Matrix 24-2 test and to determine a clinically applicable cutoff criterion for the inclusion of preperimetric glaucoma. Eyes with preperimetric glaucoma (99 eyes) were defined as having normal standard automated perimetry (SAP) results and a glaucomatous optic nerve head, along with one or more optical coherence tomography (OCT) parameters flagged as <0.05 or a retinal nerve fiber layer (RNFL) defect on red-free fundus photographs. Normal controls (122 eyes) were defined as having a normal optic disc and RNFL with normal SAP. Receiver-operating characteristic (ROC) curves were constructed to determine the best-discriminating parameter of the frequency-doubling technology (FDT) Matrix. The sensitivity, specificity, and hit ratio of all available criteria were calculated from the FDT Matrix. Pattern standard deviation (PSD) showed a larger area under the ROC curve (AUC) (0.767) than mean deviation (MD) (0.619). A pattern deviation plot (PDP) analysis by modified Anderson criteria showed the highest discriminating power, with a sensitivity of 75.76%, followed by a PSD cutoff value of 3.14 dB (sensitivity, 73.74%). FDT Matrix seems to be a valuable clinical tool in the detection of preperimetric glaucoma. Among the parameters of the FDT Matrix, PDP analysis by modified Anderson criteria may provide a reliable cutoff criterion.
Magnaporthe oryzae, the causal agent of rice blast, forms a specialized infection structure, call... more Magnaporthe oryzae, the causal agent of rice blast, forms a specialized infection structure, called an appressorium, which is crucial for penetration and infection of the host plant. Pharmacological data suggest that calcium/calmodulin-dependent signaling is involved in appressorium formation in this fungus. To understand the role of the calcium/ calmodulin-activated protein phosphatase on appressorium formation at the molecular level, MCNA, a gene encoding the catalytic subunit of calcineurin, was functionally characterized in M. oryzae. Transformants expressing sense/antisense RNA of MCNA exhibited significant reductions in mycelial growth, conidiation, appressorium formation, and pathogenicity. cDNA of MCNA functionally complemented a calcineurin disruptant strain (cmp1::LEU2 cmp2::HIS3) of Saccharomyces cerevisiae. These data suggest that calcineurin A plays important roles in signal transduction pathways involved in the infection-related morphogenesis and pathogenicity of M. oryzae.
We propose an adaptive shadow estimator to detect and eliminate the shadow of a moving object whi... more We propose an adaptive shadow estimator to detect and eliminate the shadow of a moving object while adapting to variation of illumination and the environment in an automatic manner. The proposed method discriminates between the shadow and the moving object by cascading three estimators which use the properties of chromaticity, brightness, and local intensity ratio. In the spatial adjustment step,
To solve the problem due to fast illumination change in a visual surveillance system, we propose ... more To solve the problem due to fast illumination change in a visual surveillance system, we propose a novel moving object detection algorithm for which we develop an illumination change model, a chromaticity difference model, and a brightness ratio model. When fast illumination change occurs, background pixels as well as moving object pixels are detected as foreground pixels. To separate detected foreground pixels into moving object pixels and false foreground pixels, we develop a chromaticity difference model and a brightness ratio model that estimates the intensity difference and intensity ratio of false foreground pixels, respectively. These models are based on the proposed illumination change model. Based on experimental results, the proposed method shows excellent performance under various illumination change conditions while operating in real-time.
To evaluate retinal nerve fiber layer (RNFL) thickness profiles according to the foveal position ... more To evaluate retinal nerve fiber layer (RNFL) thickness profiles according to the foveal position relative to the optic disc in myopia In 164 eyes of 164 healthy myopic subjects, the disc-foveal angle was defined as the angle between a horizontal line through the disc center and the line connecting the fovea and disc center in fundus photographs overlaid on Cirrus-HD optical coherence tomography (OCT) images. The quadrant/clock-hour based peripapillary RNFL thickness and differences between the inferior and superior (I-S) quadrant RNFL thicknesses were measured with OCT. RNFL thickness profiles were determined according to the disc-foveal angle and axial length (AL). As the disc-foveal angle increased (i.e., the fovea becomes more inferior to the optic disc), the superior RNFL decreased significantly (P = 0.003), whereas the inferior RNFL and I-S difference increased (P = 0.010 and P < 0.001, respectively). As the AL increased, the average and temporal RNFLs increased significantly (P = 0.013 and P < 0.001, respectively), and I-S difference was not affected (P = 0.231). The disc-foveal angle was significantly decreased with the distance between the fovea and the optic disc (P = 0.033). In multiple linear regression analysis, the disc-foveal angle was found to be a significant factor related to I-S differences, superior and inferior RNFL (all, P < 0.05) after adjusting for age, disc area, and AL. The intrinsic foveal position relative to the optic disc was an essential determinant of normal RNFL thickness in myopia. In particular, it was associated with the vertical asymmetry of RNFL distribution.
Studies in health technology and informatics, 2014
The inferior alveolar nerve canal is an important nerve canal in the jaw bone, and any damage to ... more The inferior alveolar nerve canal is an important nerve canal in the jaw bone, and any damage to this canal can cause pain or fatal complications. Since such damage can be caused by a wrong surgical procedure or surgery plan, accurate surgery planning is necessary. Cone-beam computed tomography (CBCT) is a three-dimensional medical imaging method that is mainly used in dental treatment; however, identifying the nerve canal is difficult in CBCT images as compared to conventional CT images. This paper proposes a new concept of a panoramic curve for nerve canal detection and a detection algorithm that is usually applied to facial recognition was introduced in this study for the automatic detection of nerve canal in CBCT images.
Osong public health and research perspectives, 2014
It is critical to implement effective multiple countermeasures to mitigate or retain the spread o... more It is critical to implement effective multiple countermeasures to mitigate or retain the spread of pandemic influenza. We propose a mathematical pandemic influenza model to assess the effectiveness of multiple countermeasures implemented in 2009. Age-specific parameters, including the transmission rate, the proportion of asymptomatic individuals, the vaccination rate, the social distancing rate, and the antiviral treatment rate are estimated using the least-square method calibrated to the incidence data. The multiple interventions (intensive vaccination, social distancing, antivrial treatment) were successfully implemented resulting in the dramatic reduction in the total number of incidence. The model output is sensitive to age-specific parameters and this leads to the fact that a more elaborate age group model should be developed and extensive further studies must be followed.
To investigate the long-term results of penetrating keratoplasty (PK) in patients with keratoconu... more To investigate the long-term results of penetrating keratoplasty (PK) in patients with keratoconus (KC) and to evaluate factors that might influence the final visual outcome. We retrospectively reviewed the data of all patients with clinical KC who had undergone PK by a single corneal surgeon in a single center from May 1980 to December 2005. The age of the patients, preoperative best-corrected visual acuity (BCVA), corneal thickness, death to preservation time, and preservation to transplantation time were recorded. Additionally, postoperative complications such as graft rejection, development of glaucoma and specular microscopy were checked during the follow-up. Sixty-nine eyes from 69 patients were finally included. The follow-up period was 8.64±6.13y. Graft rejection occurred in 4 eyes of 69 cases (5.8%), and the time to graft rejection was 2.1±1.3y. A Kaplan-Meier survival analysis showed that the estimated cumulative probability of graft rejection at 6, 13, and 17y after PK were 95.6%, 90.0%, and 78.8%, respectively. When we evaluated factors that might influence final BCVA in eyes, no disparity donor-host trephine size (same graft size) as well as higher spherical equivalent, and average K-value were associated with higher final BCVA. (P=0.006, 0.051, 0.092, and 0.021 in eyes with follow-up <8y; P=0.068, 0.065, and 0.030 in eyes with follow-up ≥8y, respectively). The long-term results of PK in patients with KC were favorable with a high percentage of good BCVA. Less myopic change and low average K-reading, as well as a surgical technique using the same size donor-recipient button may provide better visual outcomes particularly in patients with KC.
Capsular laxity is a main contributing factor in recurrent shoulder instability and is suggested ... more Capsular laxity is a main contributing factor in recurrent shoulder instability and is suggested to be correlated with increased capsular volume. Arthroscopic capsular shift combined with Bankart repair can reduce the capsular volume and reinforce the redundant capsule; however, as the capsuloligamentous structure has viscoelastic properties, it is possible for the shifted and tensioned capsule of the glenohumeral joint to slowly stretch out again over time, resulting in an increase in capsular volume. To analyze changes in capsular volume of the glenohumeral joint over time after arthroscopic Bankart repair and capsular shift, the factors associated with these changes, and their relevance to outcomes. Case series; Level of evidence, 4. Included in this study were 105 patients (mean age, 25.8 ± 8.2 years) who underwent arthroscopic Bankart repair and capsular shift for anterior shoulder instability and computed tomography arthrography (CTA) at 3 months and 1 year postoperatively and whose various functional outcomes were evaluated preoperatively and at the last follow-up (>12 months). Among these patients, 27 also had preoperative CTA. These 27 patients were used to make comparisons between preoperative and 3-month postoperative CTA measurements, and all 105 patients were used for all other comparisons. Two raters measured the separate anterior and posterior capsular volume and cross-sectional area at the 5-o'clock position using 3-dimensional (3D) Slicer software. These measurements were subsequently adjusted for each glenoid size. The changes in capsular volume and cross-sectional area at the 5-o'clock position over time, the factors related to higher change in anterior capsular volume, and their correlation with outcomes were evaluated. Three months postoperatively, the total and anterior capsular volume and anterior cross-sectional area significantly decreased; however, these values increased again at 1 year postoperatively (all P < .01). The inter- and intraobserver reliabilities of the measurements were excellent (interclass correlation coefficient = 0.717-0.945). Female sex, being an elite athlete, and more dislocations before surgery were related to a higher increase in anterior capsular volume at 1 year (all P < .05). Eight patients had redislocation, and 18 exhibited positive apprehension test postoperatively, and these patients showed significantly higher increases in anterior and total capsular volume at 1 year than did those without redislocation or positive apprehension sign (all P < .01). However, with the exception of Rowe score, a higher increase in anterior capsular volume was not related to functional outcome measures. Surgeons should be aware of the re-increase in anterior capsular volume or restretching trait of the anterior capsule over time, even after successful arthroscopic Bankart repair and capsular shift. In this study, women, elite athletes, and those with frequent dislocations were at high risk of capsular restretching. An increase in capsular volume was related to redislocation and positive apprehension sign as well as with Rowe score.
Here we report the discovery of a series of potent hepatitis C virus (HCV) NS5A inhibitors based ... more Here we report the discovery of a series of potent hepatitis C virus (HCV) NS5A inhibitors based on the benzidine prolinamide backbone. Taking a simple synthetic route, we developed a novel inhibitor structure, which allows easy modification, and through optimization of the capping group, we identified compound 6 with highly potent anti-HCV activity. Compound 6 is nontoxic and is anticipated to be an effective HCV drug candidate.
To use swept-source optical coherence tomography (OCT) to image the posterior sclera at the poste... more To use swept-source optical coherence tomography (OCT) to image the posterior sclera at the posterior pole and around the optic nerve head (ONH) and measure the subfoveal scleral thickness and laminar thickness to evaluate the relationship between the measured thicknesses and ocular parameters. Prospective, cross-sectional design. The study included 103 patients with glaucoma and 43 controls with axial lengths more than 26 mm. Swept-source OCT images were obtained to capture the subfoveal and ONH regions. Subfoveal scleral thickness and laminar thickness were measured from obtained B-scan images. To verify the reproducibility of the measurement, intraclass correlation coefficients were calculated from selected B-scans. Scleral and laminar thicknesses in patients with normal-tension glaucoma (NTG) was compared with that in patients with primary open-angle glaucoma (POAG). A Pearson correlation was calculated to assess the relationships of scleral and laminar thicknesses with ocular parameters. Posterior scleral thickness could be measured in 68.4% of patients, and laminar thickness could be measured in 88.6% by using swept-source OCT. Interobserver and intraobserver measurement reproducibility was moderate to excellent. The subfoveal scleral thickness was 670.84 ± 160.60 μm in the POAG group and 496.55 ± 115.20 μm in the NTG group; a significant difference between the groups was observed. Subfoveal scleral thickness (r = -0.677, P < 0.001) was negatively correlated with axial length only in patients with NTG, not in patients with POAG. Swept-source OCT detected differences in the thicknesses of the posterior sclera between eyes with NTG and eyes with POAG. Subfoveal scleral thickness was negatively correlated with axial length only in eyes with NTG.
Investigative ophthalmology & visual science, Jan 30, 2014
To assess the relationship between serum level of 25-hydroxyvitamin D (25(OH)D) and refractive er... more To assess the relationship between serum level of 25-hydroxyvitamin D (25(OH)D) and refractive error in Korean adolescents. A total of 2038 adolescent aged 13 to 18 years, who participated in the Korea National Health and Nutrition Examination Survey (KNHANES) from 2008 to 2011 underwent refractive examination using an autorefractor. Serum 25(OH)D concentration and other potential risk factors were examined. Multivariate regression analysis was performed to investigate the association between serum 25(OH)D and spherical equivalent (SE). Among the participants, 80.1% had myopia (-0.5 diopters [D] or more myopic) and 8.9% had high myopia (-6.0 D or more myopia). Age, total energy/Ca intake, area of residence, parental income, and smoking experience were significantly different among groups according to SE (All, P < 0.05). The age-adjusted distribution of SE according to serum 25(OH)D concentration showed a positive relationship (r = 0.067, P = 0.012). The myopia group had a significant positive relationship between SE and serum 25(OH)D tertile concentration (P = 0.020), whereas the nonmyopia group did not have any significant relationship (P = 0.599). In multiple linear regression analyses, SE was significantly associated with low serum 25(OH)D concentration after adjustment for area of residence, parental income, total energy intake, dietary Ca intake, milk consumption, and smoking experience (P = 0.047). The prevalence of high myopia was significantly associated with the lowest tertile of serum 25(OH)D concentration after adjustment for the confounding factors (P = 0.017). Low serum 25(OH)D concentration was associated with myopia prevalence in Korean adolescents. This relationship was particularly notable in adolescents with high myopia.
Atopic dermatitis (AD) is a chronic inflammatory skin disease with biphasic T cell-mediated abnor... more Atopic dermatitis (AD) is a chronic inflammatory skin disease with biphasic T cell-mediated abnormalities. Staphylococcal superantigens contribute to the exacerbation of inflammation in AD. The underlying immunopathological mechanisms are not fully understood. To determine whether epicutaneous application of recombinant staphylococcal enterotoxin A (rSEA) would exacerbate AD-like allergic inflammation induced by 2, 4-dinitrochlorobenzene (DNCB) and house dust mite extract (Dermatophagoides farinae extract, DFE) in a murine model. We first established an AD-like model using BALB/c mice exposed to DNCB/DFE on the ear. Next, Staphylococcus (S.) aureus or rSEA were topically applied to the mice. We evaluated the clinical and histopathological features of the animals. Serum immunoglobulin levels were also measured. In addition, real-time PCR analysis of cytokines produced by T cell subsets in the ears was conducted. Mice treated with S. aureus and rSEA had more severe clinical symptoms, including increased mean dermatitis scores and ear thickness, compared to animals with only AD-like lesions. Total IgE, IgG2a and serum histamine levels were increased in all groups except the normal control group. The S. aureus- and rSEA-treated groups showed increased levels of cytokines such as IL-4, IL-13, INF-γ, IL-17, and IL-18. In particular, increased cytokine expression was more conspicuous in the rSEA-treated group than in mice exposed to S. aureus. The results of this study showed that topical exposure to rSEA as well as SEA-producing S. aureus aggravate atopic skin inflammation. This may be associated with the induction of a mixed Th1/Th2 type dermatitis.
To determine the impact of β-1,3-glucan isolated from Euglena gracilis on corneal epithelial cell... more To determine the impact of β-1,3-glucan isolated from Euglena gracilis on corneal epithelial cell migration and on wound healing in a rat alkali burn model. Immortalized human corneal epithelial cells (HCECs) were cultured in media with 50, 100 and 200 μg/mL laminarin (β-1,3- and β-1,6-glucans), β-1,3-glucan and hyaluronic acid (HA)-conjugated β-1,3-glucan; Dulbecco's modified Eagle's medium (DMEM)/nutrient mixture F-12 (negative control) and serum containing DMEM/nutrient mixture F-12 (positive control). Migration assays were conducted via the manual scraping of HCECs. Next, alkali injuries were induced using 1 N NaOH in 40 eyes of 40 Sprague-Dawley male rats. The injury-only group (n = 10) received topical phosphate-buffered saline four times a day for 2 d. The study groups received 200 μg/mL topical laminarin (n = 10), β-1,3-glucan (n = 10) and β-1,3-glucan HA (n = 10). Using slit-lamp biomicroscopy, injured corneas were evaluated in terms of re-epithelialization and opacity, and tissue sections were histologically analyzed. Migration assay rates were enhanced as laminarin and β-1,3-glucan increased, compared to negative control cells (all p < 0.05). In the comparison between β-1,3-glucan and its HA conjugate form, β-1,3-glucan-HA showed more enhanced migration rate than β-1,3-glucan (p < 0.05). In rat alkali burn model, wound-healing ratio was greatest in β-1,3-glucan-HA groups (96.0 ± 4.1%), followed by β-1,3-glucan (86.0 ± 6.5%), laminarin (67.0 ± 7.5%) and injury-only group (54.0 ± 6.5%) (p < 0.0001; ANOVA). The opacity score was also lowest in β-1,3-glucan-HA groups (3.0 ± 0.75), followed by β-1,3-glucan (3.4 ± 0.5), laminarin (3.7 ± 0.8) and injury-only group (4.7 ± 0.46) (p < 0.0001; ANOVA) Histologically, relatively fewer polymorphonuclear leukocytes infiltrated the corneal stroma in the β-1,3-glucan and β-1,3-glucan-HA groups, compared to the injury-only group. β-1,3-Glucan, particularly when conjugated with HA, promoted epithelial wound healing in vitro and suppressed the acute inflammatory reaction in corneal alkali burns.
To define the diagnostic precision of the Humphrey Matrix 24-2 test and to determine a clinically... more To define the diagnostic precision of the Humphrey Matrix 24-2 test and to determine a clinically applicable cutoff criterion for the inclusion of preperimetric glaucoma. Eyes with preperimetric glaucoma (99 eyes) were defined as having normal standard automated perimetry (SAP) results and a glaucomatous optic nerve head, along with one or more optical coherence tomography (OCT) parameters flagged as <0.05 or a retinal nerve fiber layer (RNFL) defect on red-free fundus photographs. Normal controls (122 eyes) were defined as having a normal optic disc and RNFL with normal SAP. Receiver-operating characteristic (ROC) curves were constructed to determine the best-discriminating parameter of the frequency-doubling technology (FDT) Matrix. The sensitivity, specificity, and hit ratio of all available criteria were calculated from the FDT Matrix. Pattern standard deviation (PSD) showed a larger area under the ROC curve (AUC) (0.767) than mean deviation (MD) (0.619). A pattern deviation plot (PDP) analysis by modified Anderson criteria showed the highest discriminating power, with a sensitivity of 75.76%, followed by a PSD cutoff value of 3.14 dB (sensitivity, 73.74%). FDT Matrix seems to be a valuable clinical tool in the detection of preperimetric glaucoma. Among the parameters of the FDT Matrix, PDP analysis by modified Anderson criteria may provide a reliable cutoff criterion.
Magnaporthe oryzae, the causal agent of rice blast, forms a specialized infection structure, call... more Magnaporthe oryzae, the causal agent of rice blast, forms a specialized infection structure, called an appressorium, which is crucial for penetration and infection of the host plant. Pharmacological data suggest that calcium/calmodulin-dependent signaling is involved in appressorium formation in this fungus. To understand the role of the calcium/ calmodulin-activated protein phosphatase on appressorium formation at the molecular level, MCNA, a gene encoding the catalytic subunit of calcineurin, was functionally characterized in M. oryzae. Transformants expressing sense/antisense RNA of MCNA exhibited significant reductions in mycelial growth, conidiation, appressorium formation, and pathogenicity. cDNA of MCNA functionally complemented a calcineurin disruptant strain (cmp1::LEU2 cmp2::HIS3) of Saccharomyces cerevisiae. These data suggest that calcineurin A plays important roles in signal transduction pathways involved in the infection-related morphogenesis and pathogenicity of M. oryzae.
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