28 results on '"Kyoung Min Lee"'
Search Results
2. Radiographic differences in the concomitant deformities in two types of medial ankle osteoarthritis.
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Wooyoung Choi, Chin Youb Chung, Moon Seok Park, Sanghoon Lee, and Kyoung Min Lee
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Medicine ,Science - Abstract
ObjectivesMotion preserving surgeries could be unsuccessful because of underestimation of deformities of the foot and knee in ankle osteoarthritis. This study aimed to investigate the concomitant deformities in medial ankle osteoarthritis and the difference between the two types, varus angulation and medial translation.MethodsA retrospective study was conducted using medical records and radiographic data. Patients with medial ankle osteoarthritis that underwent weight-bearing X ray imaging and radiographic measurements including tibial plafond inclination (TPI), tibiotalar tilt angle (TT), lateral talo-first metatarsal angle, naviculo-cuboid overlap, and mechanical tibiofemoral angle (mTFA) were studied. The patients were categorized into two groups, the varus angulation group (TT ≥4°) and medial translation group (TT ResultsA total of 102 patients (male = 44; female = 58) were included; the mean age was 64.9 years (SD 8.3 years). The varus rotation group (N = 66) showed a significantly smaller lateral talo-first metatarsal angle (pConclusionsVarus angulation of the ankle was correlated with knee alignment and foot deformity. Radiographic indices were different between the varus angulation and medial translation groups. The role of concomitant deformities needs to be further investigated in terms of a causal relationship. Surgeons need to pay attention to concomitant deformities in the treatment of medial ankle osteoarthritis.
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- 2021
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3. Central retinal vascular trunk deviation in unilateral normal-tension glaucoma.
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Ho-Kyung Choung, Martha Kim, Sohee Oh, Kyoung Min Lee, and Seok Hwan Kim
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Medicine ,Science - Abstract
PurposeTo investigate whether the position of the central retinal vascular trunk (CRVT), as a surrogate of lamina cribrosa (LC) offset, was associated with the presence of glaucoma in normal-tension glaucoma (NTG) patients.MethodsThe position of the CRVT was measured as the deviation from the center of the Bruch's membrane opening (BMO), as delineated by spectral-domain optical coherence tomography imaging. The offset index was calculated as the distance of the CRVT from the BMO center relative to that of the BMO margin. The angular deviation of CRVT was measured with the horizontal nasal midline as 0° and the superior location as a positive value. The offset index and angular deviation were compared between glaucoma and fellow control eyes within individuals.ResultsNTG eyes had higher baseline intraocular pressure (P = 0.001), a larger β-zone parapapillary atrophy area (P = 0.013), and a larger offset index (PConclusionsThe offset index was larger in the unilateral NTG eyes, which fact is suggestive of the potential role of LC/BMO offset as a loco-regional susceptibility factor.
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- 2021
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4. Relationship between ankle varus moment during gait and radiographic measurements in patients with medial ankle osteoarthritis.
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Ji Hye Choi, Hee Soo Han, Young Jin Park, Seungbum Koo, Taeyong Lee, and Kyoung Min Lee
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Medicine ,Science - Abstract
BackgroundKinetic data obtained during gait can be used to clarify the biomechanical pathogenesis of osteoarthritis of the lower extremity. This study aimed to investigate the difference in ankle varus moment between the varus angulation and medial translation types of medial ankle osteoarthritis, and to identify the radiographic measurements associated with ankle varus moment.MethodsTwenty-four consecutive patients [mean age 65.8 (SD) 8.0 years; 9 men and 15 women] with medial ankle osteoarthritis were included. Fourteen and 10 patients had the varus angulation (tibiotalar tilt angle≥3 degrees) and medial translation (tibiotalar tilt angleResultsThe mean tibial plafond inclination, tibiotalar tilt angle, talar dome inclination, lateral talo-first metatarsal angle, and maximum ankle varus moment were 6.4 degrees (SD 3.3 degrees), 5.0 degrees (SD 4.6 degrees), 11.4 degrees (SD 5.2 degrees), -6.5 degrees (SD 11.7 degrees), and 0.185 (SD 0.082) Nm/kg, respectively. The varus angulation type showed a greater maximum ankle varus moment than the medial translation type (p = .005). The lateral talo-first metatarsal angle was significantly associated with the maximum ankle varus moment (p = .041) in the multiple regression analysis.ConclusionThe varus angulation type of medial ankle osteoarthritis is considered to be more imbalanced biomechanically than the medial displacement type. The lateral talo-first metatarsal angle, being significantly associated with the ankle varus moment, should be considered for correction during motion-preserving surgeries for medial ankle osteoarthritis to restore the biomechanical balance of the ankle.
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- 2021
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5. Hemisphere opposite to vascular trunk deviation is earlier affected by glaucomatous damage in myopic high-tension glaucoma.
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Kyoung Min Lee, Martha Kim, Sohee Oh, and Seok Hwan Kim
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Medicine ,Science - Abstract
PURPOSE:To investigate whether the position of the central vascular trunk, as a surrogate of lamina cribrosa (LC) shift, is associated with the initial hemisphere of visual field defect in myopic high-tension glaucoma (HTG) eyes. METHODS:The deviation of the central vascular trunk was measured from the center of the Bruch's membrane opening (BMO), which was delineated by OCT imaging. The angular deviation was measured with the horizontal nasal midline as 0° and the superior location as a positive value. The initial hemisphere developing visual field defect was defined as three connected abnormal points (having a P value with less than 0.5% probability of being normal) appearing in only one hemisphere in pattern deviation plots. If those points were observed in both hemispheres initially, the eye was classified as bi-hemispheric visual field defect. RESULTS:Initially, 36 eyes (44%) had superior visual field defects, 27 (33%) inferior visual field defects, and 18 (22%) bi-hemispheric visual field defects. After a mean follow-up of 5 years, the number of bi-hemispheric visual field defects had increased to 34 (42%). A logistic regression analysis revealed that inferior deviation of vascular trunk was the only factor associated with initial inferior visual field defect (P = 0.001), while initial bi-hemispheric visual field defects were associated with worse mean deviation at initial visits (P
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- 2020
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6. Effects of walking speed and slope on pedobarographic findings in young healthy adults.
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Seungbum Koo, Moon Seok Park, Chin Youb Chung, Ji Soo Yoon, Chulhee Park, and Kyoung Min Lee
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Medicine ,Science - Abstract
BackgroundThis study aimed to investigate the effects of walking speed and slope on foot pressure changes in young healthy adults.MethodsTwenty young healthy adults (mean age 22.4 years, SD 1.2 years; 10 male and 10 female) participated in the study. Dynamic pedobarographic data during treadmill walking were obtained for combinations of three different walking speeds (3.2 km/hr, 4.3 km/hr, and 5.4 km/hr) and 5 different slopes (downhill 8 degrees, downhill 4 degrees, ground walking (0 degree), uphill 4 degrees, and uphill 8 degrees). Pedobarographic data such as the peak pressure and pressure-time integral were measured on five plantar segments: medial forefoot (MFF), lateral forefoot (LFF), medial midfoot (MMF), lateral midfoot (LMF), and heel. Maximum ankle dorsiflexion was also recorded using the Plug in Gait marker set.ResultsAll participants maintained heel-toe gait in all walking conditions. The peak pressure on the MFF during downhill slope walking was lower than that during ground and uphill walking, whereas the peak pressure on the MFF during uphill slope walking was similar to that during ground walking at each walking speed. The peak pressures on the heel were similar for different walking slopes at each walking speed. The peak pressures on the MFF and heel increased with an increase in walking speed. The pressure-time integral of the MFF did not show significant changes at different walking speeds and slopes. The pressure-time integral of the heel increased with an increase in walking slope and decrease in walking speed.ConclusionsDifferent walking speeds and slopes affected the pedobarographic characteristics of young healthy adults. Downhill walking with slower speed appeared to be beneficial to reduce or optimize MFF pressures, while downhill walking at a comfortable speed would be helpful to reduce or optimize heel pressures. The findings of this study have clinical implications in recommending activities to patients with foot pressure-related symptoms and disorders.
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- 2019
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7. Correction: Effects of walking speed and slope on pedobarographic findings in young healthy adults.
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Seungbum Koo, Moon Seok Park, Chin Youb Chung, Ji Soo Yoon, Chulhee Park, and Kyoung Min Lee
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Medicine ,Science - Abstract
[This corrects the article DOI: 10.1371/journal.pone.0220073.].
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- 2019
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8. Factors associated with visual field defects of optic disc drusen.
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Kyoung Min Lee, Se Joon Woo, and Jeong-Min Hwang
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Medicine ,Science - Abstract
To investigate the prevalence and risk factors for visual field defect in patients with optic disc drusen (ODD).We assessed the visual field status of patients with ODD whose diagnosis were confirmed by spectral-domain optical coherence tomography (SD-OCT). Visual field defects were classified as normal, enlarged blind spot, or other defects. ODD were classified into either type 1 (without hyperreflective border and heterogenic internal reflectance) or type 2 (with hyperreflective border and lower internal reflectance). The prevalence and risk factors for each visual field defect was analyzed using logistic regression analysis and classification and regression tree (CART) modeling.Of the 40 eyes with ODD, 33 (83%) eyes were categorized as type 1 and 7 (17%) eyes were categorized as type 2 ODD. Regarding the visual field defects, 19 (48%) eyes showed normal visual field, 11 (28%) eyes showed enlarged blind spot, and 9 (24%) eyes showed other defects. The latter was more frequent in type 2 ODD (P = 0.001). Logistic regression analysis revealed that the factor associated with other defects was the thinning of the average retinal nerve fiber layer (RNFL) (per 10 μm decrease, OR = 3.436, P = 0.004), and the factor associated with enlarged blind spot was the height of ODD (per 100 μm increase, OR = 3.956, P = 0.023). CART modeling revealed that the average RNFL thickness lesser than 85.5 μm, and then the ODD height larger than 348 μm were the best split-up factors for predicting the type of visual field defects.In this study, one-quarter of ODD patients showed abnormal visual field defect other than enlarged blind spot. These other visual field defects appeared to be associated with the axonal loss in the eyes with type 2 ODD.
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- 2018
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9. Factors associated with knee pain in 5148 women aged 50 years and older: A population-based study.
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Kyoung Min Lee, Seung-Baik Kang, Chin Youb Chung, Moon Seok Park, Dong-Wan Kang, and Chong Bum Chang
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Medicine ,Science - Abstract
This study was performed to investigate the factors associated with the level of knee pain in a nationally representative sample of noninstitutionalized women aged 50 years or older.Women aged 50 years or older were selected and included in the data analyses from the Korean National Health and Nutrition Examination Surveys (2010-2013). Those having malignant diseases or using osteoarthritis medication were excluded. Significant factors associated with the level of knee pain were analyzed using multivariate regression analysis.A total of 5148 women (average age, 62.9 years; standard deviation, 9.3 years) were included. For women without knee osteoarthritis, level of hip pain (p
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- 2018
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10. Association between diabetic foot ulcer and diabetic retinopathy.
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Duck Jin Hwang, Kyoung Min Lee, Moon Seok Park, Sung Hee Choi, Ji In Park, Joon Hee Cho, Kyu Hyung Park, and Se Joon Woo
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Medicine ,Science - Abstract
PURPOSE:We aimed to investigate the prevalence of diabetic retinopathy (DR) in patients with diabetic foot ulcer (DFU) and elucidate the association between DR and DFU severities and their shared risk factors. METHODS:A retrospective review was conducted on DFU patients who underwent ophthalmic and vascular examinations within 6 months; 100 type 2 diabetic patients with DFU were included. The medical records of 2496 type 2 diabetic patients without DFU served as control data. DR prevalence and severity were assessed in DFU patients. DFU patients were compared with the control group regarding each clinical variable. Additionally, DFU patients were divided into two groups according to DR severity and compared. RESULTS:Out of 100 DFU patients, 90 patients (90%) had DR and 55 (55%) had proliferative DR (PDR). There was no significant association between DR and DFU severities (R = 0.034, p = 0.734). A multivariable analysis comparing type 2 diabetic patients with and without DFUs showed that the presence of DR [OR, 226.12; 95% confidence interval (CI), 58.07-880.49; p < 0.001] and proliferative DR [OR, 306.27; 95% CI, 64.35-1457.80; p < 0.001), higher HbA1c (%, OR, 1.97, 95% CI, 1.46-2.67; p < 0.001), higher serum creatinine (mg/dL, OR, 1.62, 95% CI, 1.06-2.50; p = 0.027), older age (years, OR, 1.12; 95% CI, 1.06-1.17; p < 0.001), higher pulse pressure (mmHg, OR, 1.03; 95% CI, 1.00-1.06; p = 0.025), lower cholesterol (mg/dL, OR, 0.94; 95% CI, 0.92-0.97; p < 0.001), lower BMI (kg/m2, OR, 0.87, 95% CI, 0.75-1.00; p = 0.044) and lower hematocrit (%, OR, 0.80, 95% CI, 0.74-0.87; p < 0.001) were associated with DFUs. In a subgroup analysis of DFU patients, the PDR group had a longer duration of diabetes mellitus, higher serum BUN, and higher serum creatinine than the non-PDR group. In the multivariable analysis, only higher serum creatinine was associated with PDR in DFU patients (OR, 1.37; 95% CI, 1.05-1.78; p = 0.021). CONCLUSIONS:Diabetic retinopathy is prevalent in patients with DFU and about half of DFU patients had PDR. No significant association was found in terms of the severity of these two diabetic complications. To prevent blindness, patients with DFU, and especially those with high serum creatinine, should undergo retinal examinations for timely PDR diagnosis and management.
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- 2017
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11. Factors Associated with the Retinal Nerve Fiber Layer Loss after Acute Primary Angle Closure: A Prospective EDI-OCT Study.
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Eun Ji Lee, Tae-Woo Kim, Kyoung Min Lee, Seung Hyen Lee, and Hyunjoong Kim
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Medicine ,Science - Abstract
PURPOSE:To determine the factors associated with retinal nerve fiber layer (RNFL) loss in eyes with acute primary angle-closure (APAC), particularly focusing on the influence of the change in the anterior lamina cribrosa surface depth (LCD). METHODS:After the initial presentation, 30 eyes with unilateral APAC were followed up at the following specific time points over a 12-month period: 1 week, 1~2 months, 2~3 months, 5~6 months, and 11~12 months. These follow-ups involved intraocular pressure measurements, enhanced depth-imaging spectral-domain optical coherence tomography (SD-OCT) scanning of the optic disc, and measurements of the circumpapillary RNFL thickness. The prelaminar tissue thickness (PLT) and LCD were determined in the SD-OCT images obtained at each follow-up visit. RESULTS:Repeated measures analysis of variance revealed a significant pattern of decrease in the global RNFL thickness, PLT, and LCD (all p
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- 2017
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12. Comparison of the Abilities of SD-OCT and SS-OCT in Evaluating the Thickness of the Macular Inner Retinal Layer for Glaucoma Diagnosis.
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Kyoung Min Lee, Eun Ji Lee, Tae-Woo Kim, and Hyunjoong Kim
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Medicine ,Science - Abstract
PURPOSE:To compare the abilities of spectral-domain optical coherence tomography (OCT) (SD-OCT; Spectralis, Heidelberg Engineering) and swept-source OCT (SS-OCT; DRI-OCT1 Atlantis system, Topcon) for analyzing the macular inner retinal layers in diagnosing glaucoma. METHODS:The study included 60 patients with primary open-angle glaucoma (POAG) and 60 healthy control subjects. Macular cube area was scanned using SD-OCT and SS-OCT on the same day to assess the thicknesses of the macular retinal nerve fiber layer (mRNFL), ganglion cell layer plus inner plexiform layer (GCIPL), and total retinal layer in nine subfields defined by the Early Treatment Diabetic Retinopathy Study (ETDRS). The abilities of the parameters to discriminate between the POAG and control groups were assessed using areas under the receiver operating characteristic curves (AUCs). RESULTS:Glaucoma-associated mRNFL and GCIPL thinning was more common in the outer zones than inner zones for both SD-OCT and SS-OCT. The mRNFL and GCIPL measurements showed distinct pattern differences between SD-OCT and SS-OCT in each ETDRS subfield. Although the glaucoma-diagnosis ability was comparable between SD-OCT and SS-OCT for most of the parameters, AUC was significantly larger for SD-OCT measurements of the GCIPL thickness in the outer temporal zones (p = 0.003) and of the mRNFL thickness in the outer nasal zones (p = 0.001), with the former having the largest AUC for discriminating POAG from healthy eyes (AUC = 0.894). CONCLUSION:Spectralis SD-OCT and DRI SS-OCT have similar glaucoma-diagnosis abilities based on macular inner layer thickness analysis. However, Spectralis SD-OCT was potentially superior to DRI SS-OCT in detecting GCIPL thinning in the outer temporal zone, where the glaucomatous damage predominantly occurs.
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- 2016
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13. Correction: Anterior Lamina Cribrosa Insertion in Primary Open-Angle Glaucoma Patients and Healthy Subjects.
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Kyoung Min Lee, Tae-Woo Kim, Robert N Weinreb, Eun Ji Lee, Michaël J A Girard, and Jean Martial Mari
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Medicine ,Science - Published
- 2016
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14. Anterior lamina cribrosa insertion in primary open-angle glaucoma patients and healthy subjects.
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Kyoung Min Lee, Tae-Woo Kim, Robert N Weinreb, Eun Ji Lee, Michaël J A Girard, and Jean Martial Mari
- Subjects
Medicine ,Science - Abstract
PURPOSE:To determine using swept-source optical coherence tomography (SS-OCT) whether there are differences in the location of the anterior lamina cribrosa insertion (ALI) in primary open-angle glaucoma (POAG) patients and healthy subjects. METHODS:Fifty three eyes from 53 patients with POAG, and 53 eyes from 53 age-matched healthy subjects were included prospectively in Seoul National University Bundang Hospital. Twelve radial line B-scans centered on the optic disc in every half-clock-hour meridian were acquired using SS-OCT. The ALI position was assessed by measuring two parameters: (1) ALI distance (ALID)--the distance from the anterior scleral canal opening (ASCO) to the ALI; and (2) marginal anterior lamina cribrosa surface depth (mALCSD)--the perpendicular distance from the ASCO plane to the anterior lamina cribrosa surface. These parameters were compared between the two groups for each meridian. RESULTS:Both ALID (256 ± 54 vs. 209 ± 37 µm, mean ± SD, p < 0.001) and mALCSD (232 ± 63 vs. 187 ± 40 µm, p < 0.001) were significantly greater in the POAG group than in the normal group. The largest difference was observed at the 6.5 o'clock and 11.5 o'clock meridians for both ALID and mALCSD. Multiple regression analysis revealed a negative correlation between age and both ALID and mALCSD in the control group, and a negative correlation between mean deviation of the visual field test and both ALID and mALCSD in the POAG group. CONCLUSIONS:The ALI was displaced posteriorly in eyes with POAG compared to those of healthy controls. This finding suggests that the posteriorly located lamina cribrosa insertion is an important component of glaucomatous optic nerve excavation.
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- 2014
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15. Factors associated with knee pain in 5148 women aged 50 years and older: A population-based study
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Chong Bum Chang, Kyoung Min Lee, Chin Youb Chung, Dong Wan Kang, Seung Baik Kang, and Moon Seok Park
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Knee Joint ,Physiology ,Knees ,Sensory Physiology ,lcsh:Medicine ,Osteoarthritis ,Knee Joints ,Pathology and Laboratory Medicine ,Body Mass Index ,0302 clinical medicine ,Mathematical and Statistical Techniques ,Weight loss ,Risk Factors ,Back pain ,Medicine and Health Sciences ,030212 general & internal medicine ,lcsh:Science ,Musculoskeletal System ,Multidisciplinary ,Alcohol Consumption ,Middle Aged ,Osteoarthritis, Knee ,Nutrition Surveys ,musculoskeletal system ,Arthralgia ,Sensory Systems ,Somatosensory System ,Physical Sciences ,Regression Analysis ,Legs ,Female ,medicine.symptom ,Anatomy ,Statistics (Mathematics) ,Research Article ,musculoskeletal diseases ,medicine.medical_specialty ,Lower Back Pain ,Pain ,Research and Analysis Methods ,Pelvis ,03 medical and health sciences ,Lumbar ,Signs and Symptoms ,Rheumatology ,Diagnostic Medicine ,Republic of Korea ,medicine ,Humans ,Statistical Methods ,Aged ,Nutrition ,030203 arthritis & rheumatology ,Hip ,business.industry ,Arthritis ,Limbs (Anatomy) ,lcsh:R ,Biology and Life Sciences ,Pain Sensation ,medicine.disease ,Diet ,Joints (Anatomy) ,Knee pain ,Back Pain ,Concomitant ,Multivariate Analysis ,Physical therapy ,lcsh:Q ,business ,Body mass index ,human activities ,Mathematics ,Neuroscience - Abstract
Objective This study was performed to investigate the factors associated with the level of knee pain in a nationally representative sample of noninstitutionalized women aged 50 years or older. Methods Women aged 50 years or older were selected and included in the data analyses from the Korean National Health and Nutrition Examination Surveys (2010–2013). Those having malignant diseases or using osteoarthritis medication were excluded. Significant factors associated with the level of knee pain were analyzed using multivariate regression analysis. Results A total of 5148 women (average age, 62.9 years; standard deviation, 9.3 years) were included. For women without knee osteoarthritis, level of hip pain (p
- Published
- 2018
16. Correction: Effects of walking speed and slope on pedobarographic findings in young healthy adults
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Chin Youb Chung, Moon Seok Park, Seungbum Koo, Chulhee Park, Kyoung Min Lee, and Ji Soo Yoon
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Male ,medicine.medical_specialty ,Multidisciplinary ,Foot ,Science ,Correction ,Biomechanical Phenomena ,Walking Speed ,Preferred walking speed ,Young Adult ,Physical medicine and rehabilitation ,Pressure ,medicine ,Humans ,Medicine ,Female ,Psychology - Abstract
This study aimed to investigate the effects of walking speed and slope on foot pressure changes in young healthy adults.Twenty young healthy adults (mean age 22.4 years, SD 1.2 years; 10 male and 10 female) participated in the study. Dynamic pedobarographic data during treadmill walking were obtained for combinations of three different walking speeds (3.2 km/hr, 4.3 km/hr, and 5.4 km/hr) and 5 different slopes (downhill 8 degrees, downhill 4 degrees, ground walking (0 degree), uphill 4 degrees, and uphill 8 degrees). Pedobarographic data such as the peak pressure and pressure-time integral were measured on five plantar segments: medial forefoot (MFF), lateral forefoot (LFF), medial midfoot (MMF), lateral midfoot (LMF), and heel. Maximum ankle dorsiflexion was also recorded using the Plug in Gait marker set.All participants maintained heel-toe gait in all walking conditions. The peak pressure on the MFF during downhill slope walking was lower than that during ground and uphill walking, whereas the peak pressure on the MFF during uphill slope walking was similar to that during ground walking at each walking speed. The peak pressures on the heel were similar for different walking slopes at each walking speed. The peak pressures on the MFF and heel increased with an increase in walking speed. The pressure-time integral of the MFF did not show significant changes at different walking speeds and slopes. The pressure-time integral of the heel increased with an increase in walking slope and decrease in walking speed.Different walking speeds and slopes affected the pedobarographic characteristics of young healthy adults. Downhill walking with slower speed appeared to be beneficial to reduce or optimize MFF pressures, while downhill walking at a comfortable speed would be helpful to reduce or optimize heel pressures. The findings of this study have clinical implications in recommending activities to patients with foot pressure-related symptoms and disorders.
- Published
- 2019
17. Effects of walking speed and slope on pedobarographic findings in young healthy adults
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Moon Seok Park, Kyoung Min Lee, Chin Youb Chung, Chulhee Park, Seungbum Koo, and Ji Soo Yoon
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Kinematics ,Heel ,Physiology ,Peak pressure ,Orthopedic Surgery ,Walking ,Pathology and Laboratory Medicine ,Treadmill walking ,Endocrinology ,0302 clinical medicine ,Medicine and Health Sciences ,Foot pressure ,Musculoskeletal System ,Ulcers ,Multidisciplinary ,Feet ,Physics ,Classical Mechanics ,medicine.anatomical_structure ,Physical Sciences ,Medicine ,Legs ,Anatomy ,Research Article ,medicine.medical_specialty ,Endocrine Disorders ,Science ,Pain ,Surgical and Invasive Medical Procedures ,03 medical and health sciences ,Signs and Symptoms ,Musculoskeletal System Procedures ,Physical medicine and rehabilitation ,Diagnostic Medicine ,Diabetes Mellitus ,medicine ,Ankle dorsiflexion ,Neuropathic Pain ,Biological Locomotion ,business.industry ,Forefoot ,Ankles ,Biology and Life Sciences ,030229 sport sciences ,Gait ,body regions ,Preferred walking speed ,Body Limbs ,Metabolic Disorders ,business ,human activities ,030217 neurology & neurosurgery - Abstract
BackgroundThis study aimed to investigate the effects of walking speed and slope on foot pressure changes in young healthy adults.MethodsTwenty young healthy adults (mean age 22.4 years, SD 1.2 years; 10 male and 10 female) participated in the study. Dynamic pedobarographic data during treadmill walking were obtained for combinations of three different walking speeds (3.2 km/hr, 4.3 km/hr, and 5.4 km/hr) and 5 different slopes (downhill 8 degrees, downhill 4 degrees, ground walking (0 degree), uphill 4 degrees, and uphill 8 degrees). Pedobarographic data such as the peak pressure and pressure-time integral were measured on five plantar segments: medial forefoot (MFF), lateral forefoot (LFF), medial midfoot (MMF), lateral midfoot (LMF), and heel. Maximum ankle dorsiflexion was also recorded using the Plug in Gait marker set.ResultsAll participants maintained heel-toe gait in all walking conditions. The peak pressure on the MFF during downhill slope walking was lower than that during ground and uphill walking, whereas the peak pressure on the MFF during uphill slope walking was similar to that during ground walking at each walking speed. The peak pressures on the heel were similar for different walking slopes at each walking speed. The peak pressures on the MFF and heel increased with an increase in walking speed. The pressure-time integral of the MFF did not show significant changes at different walking speeds and slopes. The pressure-time integral of the heel increased with an increase in walking slope and decrease in walking speed.ConclusionsDifferent walking speeds and slopes affected the pedobarographic characteristics of young healthy adults. Downhill walking with slower speed appeared to be beneficial to reduce or optimize MFF pressures, while downhill walking at a comfortable speed would be helpful to reduce or optimize heel pressures. The findings of this study have clinical implications in recommending activities to patients with foot pressure-related symptoms and disorders.
- Published
- 2019
18. Comparison of the Abilities of SD-OCT and SS-OCT in Evaluating the Thickness of the Macular Inner Retinal Layer for Glaucoma Diagnosis
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Eun Ji Lee, Tae Woo Kim, Kyoung Min Lee, and Hyunjoong Kim
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0301 basic medicine ,Retinal Ganglion Cells ,Male ,Fovea Centralis ,Eye Diseases ,genetic structures ,Vision ,Glaucoma ,Social Sciences ,lcsh:Medicine ,Diagnostic Radiology ,chemistry.chemical_compound ,0302 clinical medicine ,Nerve Fibers ,Animal Cells ,Area under curve ,Medicine and Health Sciences ,Psychology ,Macula Lutea ,Prospective Studies ,lcsh:Science ,Tomography ,Neurons ,Multidisciplinary ,medicine.diagnostic_test ,Radiology and Imaging ,Physics ,Classical Mechanics ,Middle Aged ,medicine.anatomical_structure ,Area Under Curve ,Physical Sciences ,Sensory Perception ,Female ,Anatomy ,Cellular Types ,Glaucoma, Open-Angle ,Tomography, Optical Coherence ,Research Article ,medicine.medical_specialty ,Ganglion Cells ,Imaging Techniques ,Ocular Anatomy ,Research and Analysis Methods ,03 medical and health sciences ,Optical coherence tomography ,Diagnostic Medicine ,Ocular System ,Ophthalmology ,medicine ,Humans ,Aged ,Damage Mechanics ,business.industry ,lcsh:R ,Fovea centralis ,Biology and Life Sciences ,Afferent Neurons ,Retinal ,Cell Biology ,medicine.disease ,Axons ,eye diseases ,030104 developmental biology ,Cross-Sectional Studies ,chemistry ,ROC Curve ,Case-Control Studies ,030221 ophthalmology & optometry ,Optometry ,Eyes ,lcsh:Q ,sense organs ,business ,Head ,Neuroscience - Abstract
Purpose To compare the abilities of spectral-domain optical coherence tomography (OCT) (SD-OCT; Spectralis, Heidelberg Engineering) and swept-source OCT (SS-OCT; DRI-OCT1 Atlantis system, Topcon) for analyzing the macular inner retinal layers in diagnosing glaucoma. Methods The study included 60 patients with primary open-angle glaucoma (POAG) and 60 healthy control subjects. Macular cube area was scanned using SD-OCT and SS-OCT on the same day to assess the thicknesses of the macular retinal nerve fiber layer (mRNFL), ganglion cell layer plus inner plexiform layer (GCIPL), and total retinal layer in nine subfields defined by the Early Treatment Diabetic Retinopathy Study (ETDRS). The abilities of the parameters to discriminate between the POAG and control groups were assessed using areas under the receiver operating characteristic curves (AUCs). Results Glaucoma-associated mRNFL and GCIPL thinning was more common in the outer zones than inner zones for both SD-OCT and SS-OCT. The mRNFL and GCIPL measurements showed distinct pattern differences between SD-OCT and SS-OCT in each ETDRS subfield. Although the glaucoma-diagnosis ability was comparable between SD-OCT and SS-OCT for most of the parameters, AUC was significantly larger for SD-OCT measurements of the GCIPL thickness in the outer temporal zones (p = 0.003) and of the mRNFL thickness in the outer nasal zones (p = 0.001), with the former having the largest AUC for discriminating POAG from healthy eyes (AUC = 0.894). Conclusion Spectralis SD-OCT and DRI SS-OCT have similar glaucoma-diagnosis abilities based on macular inner layer thickness analysis. However, Spectralis SD-OCT was potentially superior to DRI SS-OCT in detecting GCIPL thinning in the outer temporal zone, where the glaucomatous damage predominantly occurs.
- Published
- 2016
19. Correction: Anterior Lamina Cribrosa Insertion in Primary Open-Angle Glaucoma Patients and Healthy Subjects
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Jean Martial Mari, Tae Woo Kim, Robert N. Weinreb, Eun Lee, Michael J A Girard, and Kyoung Min Lee
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Multidisciplinary ,Blindness ,Open angle glaucoma ,General Science & Technology ,business.industry ,lcsh:R ,Healthy subjects ,lcsh:Medicine ,medicine.disease ,Bioinformatics ,medicine ,Optometry ,lcsh:Q ,business ,lcsh:Science ,health care economics and organizations - Abstract
There is an error in the Funding section. The correct funding information is as follows: The work was supported by a grant from the Seoul National University Bundang Hospital Research Fund (02-2014-047), the National Research Foundation of Korea funded by the Korean Government (no. 2013R1A1A1A05004781) and an unrestricted grant from Research to Prevent Blindness (New York, NY). The funding organizations had no role in the design or conduct of this research.
- Published
- 2016
20. Factors Associated with the Retinal Nerve Fiber Layer Loss after Acute Primary Angle Closure: A Prospective EDI-OCT Study
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Tae Woo Kim, Hyunjoong Kim, Kyoung Min Lee, Seung Hyen Lee, and Eun Ji Lee
- Subjects
Male ,0301 basic medicine ,Intraocular pressure ,Time Factors ,Eye Diseases ,genetic structures ,Vision ,Visual Acuity ,Nerve fiber layer ,Optic disk ,lcsh:Medicine ,Social Sciences ,Glaucoma ,Cornea ,chemistry.chemical_compound ,Nerve Fibers ,0302 clinical medicine ,Animal Cells ,Medicine and Health Sciences ,Psychology ,Prospective Studies ,lcsh:Science ,Neurons ,Aged, 80 and over ,Multidisciplinary ,Remission Induction ,Middle Aged ,medicine.anatomical_structure ,Optic nerve ,Sensory Perception ,Female ,Anatomy ,Cellular Types ,Glaucoma, Angle-Closure ,Tomography, Optical Coherence ,Research Article ,Optic disc ,medicine.medical_specialty ,Ocular Anatomy ,Optic Disk ,Optic Disc ,Retina ,03 medical and health sciences ,Ocular System ,Ophthalmology ,medicine ,Humans ,Intraocular Pressure ,Aged ,Choroid ,business.industry ,lcsh:R ,Biology and Life Sciences ,Repeated measures design ,Optic Nerve ,Retinal ,Cell Biology ,medicine.disease ,eye diseases ,030104 developmental biology ,chemistry ,Cellular Neuroscience ,030221 ophthalmology & optometry ,Eyes ,lcsh:Q ,sense organs ,business ,Head ,Neuroscience - Abstract
PURPOSE:To determine the factors associated with retinal nerve fiber layer (RNFL) loss in eyes with acute primary angle-closure (APAC), particularly focusing on the influence of the change in the anterior lamina cribrosa surface depth (LCD). METHODS:After the initial presentation, 30 eyes with unilateral APAC were followed up at the following specific time points over a 12-month period: 1 week, 1~2 months, 2~3 months, 5~6 months, and 11~12 months. These follow-ups involved intraocular pressure measurements, enhanced depth-imaging spectral-domain optical coherence tomography (SD-OCT) scanning of the optic disc, and measurements of the circumpapillary RNFL thickness. The prelaminar tissue thickness (PLT) and LCD were determined in the SD-OCT images obtained at each follow-up visit. RESULTS:Repeated measures analysis of variance revealed a significant pattern of decrease in the global RNFL thickness, PLT, and LCD (all p
- Published
- 2017
21. The frontal eye fields limit the capacity of visual short-term memory in rhesus monkeys
- Author
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Kyung Ha Ahn and Kyoung Min Lee
- Subjects
Central Nervous System ,genetic structures ,Visual System ,Cognitive Neuroscience ,Spatial Behavior ,Neurophysiology ,lcsh:Medicine ,Biology ,Eye ,Behavioral Neuroscience ,Cognition ,Memory ,Neuropsychology ,Saccades ,Animals ,Memory impairment ,Visual short-term memory ,Working Memory ,Color contrast ,lcsh:Science ,Motor Systems ,Multidisciplinary ,lcsh:R ,Iconic memory ,Frontal eye fields ,Macaca mulatta ,Animal Cognition ,Sensory Systems ,Chemical inactivation ,Capacity limit ,Saccade ,Female ,lcsh:Q ,Visual Fields ,Neuroscience ,Research Article - Abstract
The frontal eye fields (FEF) in rhesus monkeys have been implicated in visual short-term memory (VSTM) as well as control of visual attention. Here we examined the importance of the area in the VSTM capacity and the relationship between VSTM and attention, using the chemical inactivation technique and multi-target saccade tasks with or without the need of target-location memory. During FEF inactivation, serial saccades to targets defined by color contrast were unaffected, but saccades relying on short-term memory were impaired when the target count was at the capacity limit of VSTM. The memory impairment was specific to the FEF-coded retinotopic locations, and subject to competition among targets distributed across visual fields. These results together suggest that the FEF plays a crucial role during the entry of information into VSTM, by enabling attention deployment on targets to be remembered. In this view, the memory capacity results from the limited availability of attentional resources provided by FEF: The FEF can concurrently maintain only a limited number of activations to register the targets into memory. When lesions render part of the area unavailable for activation, the number would decrease, further reducing the capacity of VSTM.
- Published
- 2013
22. Selection of appropriate reference genes for RT-qPCR analysis in a streptozotocin-induced Alzheimer's disease model of cynomolgus monkeys (Macaca fascicularis)
- Author
-
Kyu-Tae Chang, Kang Jin Jeong, Sang-Je Park, Sang-Hyun Kim, Youngjeon Lee, Young-Hyun Kim, Kyoung-Min Kim, Ji-Su Kim, Jae-Won Huh, Sun-Uk Kim, Heui-Soo Kim, Kyoung Min Lee, and Sang-Rae Lee
- Subjects
Clinical Research Design ,Gene Expression ,lcsh:Medicine ,Biology ,Real-Time Polymerase Chain Reaction ,Streptozocin ,law.invention ,Model Organisms ,Genome Analysis Tools ,Alzheimer Disease ,law ,Reference genes ,Molecular Cell Biology ,Gene expression ,Genetics ,Animals ,Animal Models of Disease ,lcsh:Science ,Gene ,Polymerase chain reaction ,Multidisciplinary ,Gene Expression Profiling ,lcsh:R ,Brain ,Genomics ,Animal Models ,Reference Standards ,Reverse transcriptase ,Gene expression profiling ,Macaca fascicularis ,Real-time polymerase chain reaction ,Neurology ,Genes ,YWHAZ ,Medicine ,Dementia ,lcsh:Q ,Macaque ,Research Article - Abstract
Reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) has been widely used to quantify relative gene expression because of the specificity, sensitivity, and accuracy of this technique. In order to obtain reliable gene expression data from RT-qPCR experiments, it is important to utilize optimal reference genes for the normalization of target gene expression under varied experimental conditions. Previously, we developed and validated a novel icv-STZ cynomolgus monkey model for Alzheimer's disease (AD) research. However, in order to enhance the reliability of this disease model, appropriate reference genes must be selected to allow meaningful analysis of the gene expression levels in the icv-STZ cynomolgus monkey brain. In this study, we assessed the expression stability of 9 candidate reference genes in 2 matched-pair brain samples (5 regions) of control cynomolgus monkeys and those who had received intracerebroventricular injection of streptozotocin (icv-STZ). Three well-known analytical programs geNorm, NormFinder, and BestKeeper were used to choose the suitable reference genes from the total sample group, control group, and icv-STZ group. Combination analysis of the 3 different programs clearly indicated that the ideal reference genes are RPS19 and YWHAZ in the total sample group, GAPDH and RPS19 in the control group, and ACTB and GAPDH in the icv-STZ group. Additionally, we validated the normalization accuracy of the most appropriate reference genes (RPS19 and YWHAZ) by comparison with the least stable gene (TBP) using quantification of the APP and MAPT genes in the total sample group. To the best of our knowledge, this research is the first study to identify and validate the appropriate reference genes in cynomolgus monkey brains. These findings provide useful information for future studies involving the expression of target genes in the cynomolgus monkey.
- Published
- 2013
23. Intermittent Hypoxia Can Aggravate Motor Neuronal Loss and Cognitive Dysfunction in ALS Mice
- Author
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Seung Hyun Kim, Jeeheun Shon, Jeong Seon Lee, Heejaung Kim, Gye Sun Jeon, Kyung Seok Park, Kyoung Min Lee, Kwang Woo Lee, Jung-Joon Sung, Suk Won Ahn, and Sung Min Kim
- Subjects
Male ,Science ,Inflammation ,Biology ,medicine.disease_cause ,Rotarod performance test ,Mice ,In vivo ,medicine ,Animals ,Muscle Strength ,Amyotrophic lateral sclerosis ,Hypoxia ,Motor Neurons ,Multidisciplinary ,Amyotrophic Lateral Sclerosis ,Intermittent hypoxia ,Hypoxia (medical) ,medicine.disease ,Spinal cord ,Disease Models, Animal ,Oxidative Stress ,medicine.anatomical_structure ,Rotarod Performance Test ,Anesthesia ,Medicine ,Female ,medicine.symptom ,Neuroscience ,Psychomotor Performance ,Oxidative stress ,Research Article ,Signal Transduction - Abstract
BackgroundPatients with ALS may be exposed to variable degrees of chronic intermittent hypoxia. However, all previous experimental studies on the effects of hypoxia in ALS have only used a sustained hypoxia model and it is possible that chronic intermittent hypoxia exerts effects via a different molecular mechanism from that of sustained hypoxia. No study has yet shown that hypoxia (either chronic intermittent or sustained) can affect the loss of motor neurons or cognitive function in an in vivo model of ALS.ObjectiveTo evaluate the effects of chronic intermittent hypoxia on motor and cognitive function in ALS mice.MethodsSixteen ALS mice and 16 wild-type mice were divided into 2 groups and subjected to either chronic intermittent hypoxia or normoxia for 2 weeks. The effects of chronic intermittent hypoxia on ALS mice were evaluated using the rotarod, Y-maze, and wire-hanging tests. In addition, numbers of motor neurons in the ventral horn of the spinal cord were counted and western blot analyses were performed for markers of oxidative stress and inflammatory pathway activation.ResultsCompared to ALS mice kept in normoxic conditions, ALS mice that experienced chronic intermittent hypoxia had poorer motor learning on the rotarod test, poorer spatial memory on the Y-maze test, shorter wire hanging time, and fewer motor neurons in the ventral spinal cord. Compared to ALS-normoxic and wild-type mice, ALS mice that experienced chronic intermittent hypoxia had higher levels of oxidative stress and inflammation.ConclusionsChronic intermittent hypoxia can aggravate motor neuronal death, neuromuscular weakness, and probably cognitive dysfunction in ALS mice. The generation of oxidative stress with activation of inflammatory pathways may be associated with this mechanism. Our study will provide insight into the association of hypoxia with disease progression, and in turn, the rationale for an early non-invasive ventilation treatment in patients with ALS.
- Published
- 2013
24. Nocturnal Hypoxia in ALS Is Related to Cognitive Dysfunction and Can Occur as Clusters of Desaturations
- Author
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Kyoung Min Lee, Jung-Joon Sung, Kwang Woo Lee, Kyung Seok Park, Sung Min Kim, SangYun Kim, Hyunwoo Nam, and Su Yeon Park
- Subjects
Adult ,Male ,medicine.medical_specialty ,Weakness ,lcsh:Medicine ,Disease ,Nocturnal ,Biology ,Memory ,Internal medicine ,medicine ,Humans ,Amyotrophic lateral sclerosis ,Respiratory system ,Hypoxia ,lcsh:Science ,Aged ,Aged, 80 and over ,Multidisciplinary ,Amyotrophic Lateral Sclerosis ,lcsh:R ,Cognition ,Middle Aged ,Hypoxia (medical) ,medicine.disease ,Hypoventilation ,Cardiology ,Physical therapy ,Female ,lcsh:Q ,medicine.symptom ,Cognition Disorders ,Research Article - Abstract
Background: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that leads to progressive weakness of the respiratory and limb muscles. Consequently, most patients with ALS exhibit progressive hypoventilation, which worsens during sleep. The aim of this study was to evaluate the relationship between nocturnal hypoxia and cognitive dysfunction and to assess the pattern of nocturnal hypoxia in patients with ALS. Method: Twenty-five patients with definite or probable ALS underwent neuropsychologic testing, nocturnal pulse oximetry, and capnography. Patients were grouped according to the presence of nocturnal hypoxia (SpO(2)= 10% of the night) and their clinical characteristics and cognitive function were compared. Results: Compared to patients without nocturnal hypoxia, those with nocturnal hypoxia (n = 10, 40%) had poor memory retention (p = 0.039) and retrieval efficiency (p = 0.045). A cluster-of-desaturation pattern was identified in 7 patients (70%) in the Hypoxia Group. Conclusions: These results suggest that nocturnal hypoxia can be related to cognitive dysfunction in ALS. In addition, a considerable number of patients with ALS may be exposed to repeated episodes of deoxygenation-reoxygenation (a cluster-of-desaturation pattern) during sleep, which could be associated with the generation of reactive oxygen species. Further studies are required to define the exact causal relationships between these phenomena, the exact manifestations of nocturnal cluster-of-desaturation patterns, and the effect of clusters of desaturation on ALS progression.
- Published
- 2013
25. Persistence of metric biases in body representation during the body ownership illusion.
- Author
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Min-Hee Seo, Jeh-Kwang Ryu, Byung-Cheol Kim, Sang-Bin Jeon, and Kyoung-Min Lee
- Subjects
Medicine ,Science - Abstract
Our perception of the body's metric is influenced by bias according to the axis, called the systematic metric bias in body representation. Systematic metric bias was first reported as Weber's illusion and observed in several parts of the body in various patterns. However, the systematic metric bias was not observed with a fake hand under the influence of the body ownership illusion during the line length judgment task. The lack of metric bias observed during the line length judgment task with a fake hand implies that the tactile modality occupies a relatively less dominant position than perception occurring through the real body. The change in weight between visual and tactile modalities during the body ownership illusion has not been adequately investigated yet, despite being a factor that influences the perception through body ownership illusion. Therefore, this study aimed to investigate whether the dominance of vision over tactile modality is prominent, regardless of the task type. To investigate whether visual dominance persists during the process of inducing body ownership illusion regardless of task type, we introduced spatial visuotactile incongruence (2 cm, 3 cm) in the longitudinal and transverse axes during the visuotactile localization tasks and measured the intensity of the body ownership illusion using a questionnaire. The results indicated that participants perceived smaller visuotactile incongruence when the discrepancy occurred in the transverse axis rather than in the longitudinal axis. The anisotropy in the tolerance of visuotactile incongruence implies the persistence of metric biases in body representation. The results suggest the need for further research regarding the factors influencing the weight of visual and tactile modalities.
- Published
- 2022
- Full Text
- View/download PDF
26. The frontal eye fields limit the capacity of visual short-term memory in rhesus monkeys.
- Author
-
Kyoung-Min Lee and Kyung-Ha Ahn
- Subjects
Medicine ,Science - Abstract
The frontal eye fields (FEF) in rhesus monkeys have been implicated in visual short-term memory (VSTM) as well as control of visual attention. Here we examined the importance of the area in the VSTM capacity and the relationship between VSTM and attention, using the chemical inactivation technique and multi-target saccade tasks with or without the need of target-location memory. During FEF inactivation, serial saccades to targets defined by color contrast were unaffected, but saccades relying on short-term memory were impaired when the target count was at the capacity limit of VSTM. The memory impairment was specific to the FEF-coded retinotopic locations, and subject to competition among targets distributed across visual fields. These results together suggest that the FEF plays a crucial role during the entry of information into VSTM, by enabling attention deployment on targets to be remembered. In this view, the memory capacity results from the limited availability of attentional resources provided by FEF: The FEF can concurrently maintain only a limited number of activations to register the targets into memory. When lesions render part of the area unavailable for activation, the number would decrease, further reducing the capacity of VSTM.
- Published
- 2013
- Full Text
- View/download PDF
27. Selection of appropriate reference genes for RT-qPCR analysis in a streptozotocin-induced Alzheimer's disease model of cynomolgus monkeys (Macaca fascicularis).
- Author
-
Sang-Je Park, Young-Hyun Kim, Youngjeon Lee, Kyoung-Min Kim, Heui-Soo Kim, Sang-Rae Lee, Sun-Uk Kim, Sang-Hyun Kim, Ji-Su Kim, Kang-Jin Jeong, Kyoung-Min Lee, Jae-Won Huh, and Kyu-Tae Chang
- Subjects
Medicine ,Science - Abstract
Reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) has been widely used to quantify relative gene expression because of the specificity, sensitivity, and accuracy of this technique. In order to obtain reliable gene expression data from RT-qPCR experiments, it is important to utilize optimal reference genes for the normalization of target gene expression under varied experimental conditions. Previously, we developed and validated a novel icv-STZ cynomolgus monkey model for Alzheimer's disease (AD) research. However, in order to enhance the reliability of this disease model, appropriate reference genes must be selected to allow meaningful analysis of the gene expression levels in the icv-STZ cynomolgus monkey brain. In this study, we assessed the expression stability of 9 candidate reference genes in 2 matched-pair brain samples (5 regions) of control cynomolgus monkeys and those who had received intracerebroventricular injection of streptozotocin (icv-STZ). Three well-known analytical programs geNorm, NormFinder, and BestKeeper were used to choose the suitable reference genes from the total sample group, control group, and icv-STZ group. Combination analysis of the 3 different programs clearly indicated that the ideal reference genes are RPS19 and YWHAZ in the total sample group, GAPDH and RPS19 in the control group, and ACTB and GAPDH in the icv-STZ group. Additionally, we validated the normalization accuracy of the most appropriate reference genes (RPS19 and YWHAZ) by comparison with the least stable gene (TBP) using quantification of the APP and MAPT genes in the total sample group. To the best of our knowledge, this research is the first study to identify and validate the appropriate reference genes in cynomolgus monkey brains. These findings provide useful information for future studies involving the expression of target genes in the cynomolgus monkey.
- Published
- 2013
- Full Text
- View/download PDF
28. Saccade generation by the frontal eye fields in rhesus monkeys is separable from visual detection and bottom-up attention shift.
- Author
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Kyoung-Min Lee, Kyung-Ha Ahn, and Edward L Keller
- Subjects
Medicine ,Science - Abstract
The frontal eye fields (FEF), originally identified as an oculomotor cortex, have also been implicated in perceptual functions, such as constructing a visual saliency map and shifting visual attention. Further dissecting the area's role in the transformation from visual input to oculomotor command has been difficult because of spatial confounding between stimuli and responses and consequently between intermediate cognitive processes, such as attention shift and saccade preparation. Here we developed two tasks in which the visual stimulus and the saccade response were dissociated in space (the extended memory-guided saccade task), and bottom-up attention shift and saccade target selection were independent (the four-alternative delayed saccade task). Reversible inactivation of the FEF in rhesus monkeys disrupted, as expected, contralateral memory-guided saccades, but visual detection was demonstrated to be intact at the same field. Moreover, saccade behavior was impaired when a bottom-up shift of attention was not a prerequisite for saccade target selection, indicating that the inactivation effect was independent of the previously reported dysfunctions in bottom-up attention control. These findings underscore the motor aspect of the area's functions, especially in situations where saccades are generated by internal cognitive processes, including visual short-term memory and long-term associative memory.
- Published
- 2012
- Full Text
- View/download PDF
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