1.Contemporary Statistics of Acute Ischemic Stroke and Transient Ischemic Attack in 2021: Insights From the CRCS-K-NIH Registry
Do Yeon KIM ; Tai Hwan PARK ; Yong-Jin CHO ; Jong-Moo PARK ; Kyungbok LEE ; Minwoo LEE ; Juneyoung LEE ; Sang Yoon BAE ; Da Young HONG ; Hannah JUNG ; Eunvin KO ; Hyung Seok GUK ; Beom Joon KIM ; Jun Yup KIM ; Jihoon KANG ; Moon-Ku HAN ; Sang-Soon PARK ; Keun-Sik HONG ; Hong-Kyun PARK ; Jeong-Yoon LEE ; Byung-Chul LEE ; Kyung-Ho YU ; Mi Sun OH ; Dong-Eog KIM ; Dong-Seok GWAK ; Soo Joo LEE ; Jae Guk KIM ; Jun LEE ; Doo Hyuk KWON ; Jae-Kwan CHA ; Dae-Hyun KIM ; Joon-Tae KIM ; Kang-Ho CHOI ; Hyunsoo KIM ; Jay Chol CHOI ; Joong-Goo KIM ; Chul-Hoo KANG ; Sung-il SOHN ; Jeong-Ho HONG ; Hyungjong PARK ; Sang-Hwa LEE ; Chulho KIM ; Dong-Ick SHIN ; Kyu Sun YUM ; Kyusik KANG ; Kwang-Yeol PARK ; Hae-Bong JEONG ; Chan-Young PARK ; Keon-Joo LEE ; Jee Hyun KWON ; Wook-Joo KIM ; Ji Sung LEE ; Hee-Joon BAE ;
Journal of Korean Medical Science 2024;39(34):e278-
This report presents the latest statistics on the stroke population in South Korea, sourced from the Clinical Research Collaborations for Stroke in Korea-National Institute for Health (CRCS-K-NIH), a comprehensive, nationwide, multicenter stroke registry. The Korean cohort, unlike western populations, shows a male-to-female ratio of 1.5, attributed to lower risk factors in Korean women. The average ages for men and women are 67 and 73 years, respectively.Hypertension is the most common risk factor (67%), consistent with global trends, but there is a higher prevalence of diabetes (35%) and smoking (21%). The prevalence of atrial fibrillation (19%) is lower than in western populations, suggesting effective prevention strategies in the general population. A high incidence of large artery atherosclerosis (38%) is observed, likely due to prevalent intracranial arterial disease in East Asians and advanced imaging techniques.There has been a decrease in intravenous thrombolysis rates, from 12% in 2017–2019 to 10% in 2021, with no improvements in door-to-needle and door-to-puncture times, worsened by the coronavirus disease 2019 pandemic. While the use of aspirin plus clopidogrel for noncardioembolic stroke and direct oral anticoagulants for atrial fibrillation is well-established, the application of direct oral anticoagulants for non-atrial fibrillation cardioembolic strokes in the acute phase requires further research. The incidence of early neurological deterioration (13%) and the cumulative incidence of recurrent stroke at 3 months (3%) align with global figures. Favorable outcomes at 3 months (63%) are comparable internationally, yet the lack of improvement in dependency at 3 months highlights the need for advancements in acute stroke care.
2.Comparison of Factors Associated With Direct Versus Transferred-in Admission to Government-Designated Regional Centers Between Acute Ischemic Stroke and Myocardial Infarction in Korea
Dae-Hyun KIM ; Seok-Joo MOON ; Juneyoung LEE ; Jae-Kwan CHA ; Moo Hyun KIM ; Jong-Sung PARK ; Byeolnim BAN ; Jihoon KANG ; Beom Joon KIM ; Won-Seok KIM ; Chang-Hwan YOON ; Heeyoung LEE ; Seongheon KIM ; Eun Kyoung KANG ; Ae-Young HER ; Cindy W YOON ; Joung-Ho RHA ; Seong-Ill WOO ; Won Kyung LEE ; Han-Young JUNG ; Jang Hoon LEE ; Hun Sik PARK ; Yang-Ha HWANG ; Keonyeop KIM ; Rock Bum KIM ; Nack-Cheon CHOI ; Jinyong HWANG ; Hyun-Woong PARK ; Ki Soo PARK ; SangHak YI ; Jae Young CHO ; Nam-Ho KIM ; Kang-Ho CHOI ; Juhan KIM ; Jae-Young HAN ; Jay Chol CHOI ; Song-Yi KIM ; Joon-Hyouk CHOI ; Jei KIM ; Min Kyun SOHN ; Si Wan CHOI ; Dong-Ick SHIN ; Sang Yeub LEE ; Jang-Whan BAE ; Kun Sei LEE ; Hee-Joon BAE
Journal of Korean Medical Science 2022;37(42):e305-
Background:
There has been no comparison of the determinants of admission route between acute ischemic stroke (AIS) and acute myocardial infarction (AMI). We examined whether factors associated with direct versus transferred-in admission to regional cardiocerebrovascular centers (RCVCs) differed between AIS and AMI.
Methods:
Using a nationwide RCVC registry, we identified consecutive patients presenting with AMI and AIS between July 2016 and December 2018. We explored factors associated with direct admission to RCVCs in patients with AIS and AMI and examined whether those associations differed between AIS and AMI, including interaction terms between each factor and disease type in multivariable models. To explore the influence of emergency medical service (EMS) paramedics on hospital selection, stratified analyses according to use of EMS were also performed.
Results:
Among the 17,897 and 8,927 AIS and AMI patients, 66.6% and 48.2% were directly admitted to RCVCs, respectively. Multivariable analysis showed that previous coronary heart disease, prehospital awareness, higher education level, and EMS use increased the odds of direct admission to RCVCs, but the odds ratio (OR) was different between AIS and AMI (for the first 3 factors, AMI > AIS; for EMS use, AMI < AIS). EMS use was the single most important factor for both AIS and AMI (OR, 4.72 vs. 3.90). Hypertension and hyperlipidemia increased, while living alone decreased the odds of direct admission only in AMI;additionally, age (65–74 years), previous stroke, and presentation during non-working hours increased the odds only in AIS. EMS use weakened the associations between direct admission and most factors in both AIS and AMI.
Conclusions
Various patient factors were differentially associated with direct admission to RCVCs between AIS and AMI. Public education for symptom awareness and use of EMS is essential in optimizing the transportation and hospitalization of patients with AMI and AIS.
3.Cataract Surgery Practice in the Republic of Korea: A Survey of the Korean Society of Cataract and Refractive Surgery 2020
Chang Rae RHO ; Jin-Hyoung KIM ; In Kwon CHUNG ; Eun Chol KIM ; Young Keun HAN ; Sang Youp HAN ; Youngsub EOM ; Tae-Young CHUNG ; Do-Hyung LEE
Korean Journal of Ophthalmology 2021;35(4):272-279
Purpose:
To describe current cataract surgery practice patterns and trends among Korean ophthalmologists.
Methods:
A survey was conducted among members of the Korean Society of Cataract and Refractive Surgery in October 2020. Of the 998 questionnaires, 262 (26.3%) were received for analysis. Data were analyzed using descriptive statistics and compared with those of previous surveys.
Results:
The largest percentage of respondents (39%) had <5 years of practical experience, and 40% had >11 years of practical experience. The average, median, and mode monthly volumes of cataract surgeries performed by the Korean Society of Cataract and Refractive Surgery members were 31, 20, and 10 cases, respectively. Topical anesthesia was administered by 85% of the respondents. For intraocular lens (IOL) calculations, 96% of the respondents used optical biometry. The proportion of surgeons providing femtosecond laser-assisted cataract surgery increased significantly from 5% in 2018 to 29% in 2020. This increase was accompanied by an increase in the multifocal IOLs. Those who implant multifocal IOL for >10% of their cases increased from 16% (2018) to 29% (2020). Topical nonsteroidal anti-inflammatory drugs were prescribed postoperatively by 76% of the respondents. Most respondents (70%) prescribed these anti-inflammatory drugs for 4 weeks.
Conclusions
This survey provided a comprehensive update on current cataract surgery practice in the Republic of Korea. The results highlighted the increasing use of premium IOLs, femtosecond laser-assisted cataract surgery, optical biometry, and topical anesthesia to better meet the patients’ needs.
4.Fimasartan-Based Blood Pressure Control after Acute Cerebral Ischemia: The Fimasartan-Based Blood Pressure Control after Acute Cerebral Ischemia Study
Keun-Sik HONG ; Sun Uck KWON ; Jong-Ho PARK ; Jae-Kwan CHA ; Jin-Man JUNG ; Yong-Jae KIM ; Kyung Bok LEE ; Sung Il SOHN ; Yong-Seok LEE ; Joung-Ho RHA ; Jee-Hyun KWON ; Sang Won HAN ; Bum Joon KIM ; Jaseong KOO ; Jay Chol CHOI ; Sang Min SUNG ; Soo Joo LEE ; Man-Seok PARK ; Seong Hwan AHN ; Oh Young BANG ; Yang-Ha HWANG ; Hyo Suk NAM ; Jong-Moo PARK ; Hee-Joon BAE ; Eung Gyu KIM ; Kyung-Yul LEE ; Mi Sun OH
Journal of Clinical Neurology 2021;17(3):344-353
Background:
and Purpose: Blood pressure (BP) control is strongly recommended, but BP control rate has not been well studied in patients with stroke. We evaluated the BP control rate with fimasartan-based antihypertensive therapy initiated in patients with recent cerebral ischemia.
Methods:
This multicenter, prospective, single-arm trial involved 27 centers in South Korea. Key inclusion criteria were recent cerebral ischemia within 90 days and high BP [systolic blood pressure (SBP) >140 mm Hg or diastolic blood pressure (DBP) >90 mm Hg]. BP lowering was initiated with fimasartan. BP management during the follow-up was at the discretion of the responsible investigators. The primary endpoint was the target BP goal achievement rate (<140/90 mm Hg) at 24 weeks. Key secondary endpoints included achieved BP and BP changes at each visit, and clinical events (ClinicalTrials.gov Identifier: NCT03231293).
Results:
Of 1,035 patients enrolled, 1,026 were included in the safety analysis, and 951 in the efficacy analysis. Their mean age was 64.1 years, 33% were female, the median time interval from onset to enrollment was 10 days, and the baseline SBP and DBP were 162.3±16.0 and 92.2±12.4 mm Hg (mean±SD). During the study period, 55.5% of patients were maintained on fimasartan monotherapy, and 44.5% received antihypertensive therapies other than fimasartan monotherapy at at least one visit. The target BP goal achievement rate at 24-week was 67.3% (48.6% at 4-week and 61.4% at 12-week). The mean BP was 139.0/81.8±18.3/11.7, 133.8/79.2±16.4/11.0, and 132.8/78.5±15.6/10.9 mm Hg at 4-, 12-, and 24-week. The treatment-emergent adverse event rate was 5.4%, including one serious adverse event.
Conclusions
Fimasartan-based BP lowering achieved the target BP in two-thirds of patients at 24 weeks, and was generally well tolerated.
5.Percutaneous Left Atrial Appendage Occlusion Yields Favorable Neurological Outcomes in Patients with Non-Valvular Atrial Fibrillation
Oh-Hyun LEE ; Young Dae KIM ; Jung-Sun KIM ; Nak-Hoon SON ; Hui-Nam PAK ; Boyoung JOUNG ; Cheol-Woong YU ; Hyun-Jong LEE ; Woong-Chol KANG ; Eun-Seok SHIN ; Rak-kyeong CHOI ; Do-Sun LIM ; Yo Han JUNG ; Hye-Yeon CHOI ; Kyung-Yul LEE ; Bang-Hoon CHO ; Sang Won HAN ; Joong Hyun PARK ; Han-Jin CHO ; Hyung Jong PARK ; Hyo Suk NAM ; Ji Hoe HEO ; Chak-yu SO ; Gary Shing-Him CHEUNG ; Yat-yin LAM ; Xavier FREIXA ; Apostolos TZIKAS ; Yangsoo JANG ; Jai-Wun PARK
Korean Circulation Journal 2021;51(7):626-638
Background and Objectives:
Prior studies have shown that stroke patients treated with percutaneous left atrial appendage occlusion (LAAO) for non-valvular atrial fibrillation (NVAF) experience better outcomes than similar patients treated with warfarin. We investigated the impact of percutaneous left atrial appendage closure on post-stroke neurological outcomes in NVAF patients, compared with non-vitamin K antagonist oral anticoagulant (NOAC) therapy.
Methods:
Medical records for 1,427 patients in multiple registries and for 1,792 consecutive patients at 6 Korean hospitals were reviewed with respect to LAAO or NOAC treatment.Stroke severity in patients who experienced ischemic stroke or transient ischemic attack after either treatment was assessed with modified Rankin Scale (mRS) scoring at hospital discharge and at 3 and 12 months post-stroke.
Results:
mRS scores were significantly lower in LAAO patients at 3 (p<0.01) and 12 months (p<0.01) post-stroke, despite no significant differences in scores before the ischemic cerebrovascular event (p=0.22). The occurrences of disabling ischemic stroke in the LAAO and NOAC groups were 36.7% and 44.2% at discharge (p=0.47), 23.3% and 44.2% at 3 months post-stroke (p=0.04), and 13.3% and 43.0% at 12 months post-stroke (p=0.01), respectively.Recovery rates for disabling ischemic stroke at discharge to 12 months post-stroke were significantly higher for LAAO patients (50.0%) than for NOAC patients (5.6%) (p<0.01).
Conclusions
Percutaneous LAAO was associated with more favorable neurological outcomes after ischemic cerebrovascular event than NOAC treatment.
6.Fimasartan-Based Blood Pressure Control after Acute Cerebral Ischemia: The Fimasartan-Based Blood Pressure Control after Acute Cerebral Ischemia Study
Keun-Sik HONG ; Sun Uck KWON ; Jong-Ho PARK ; Jae-Kwan CHA ; Jin-Man JUNG ; Yong-Jae KIM ; Kyung Bok LEE ; Sung Il SOHN ; Yong-Seok LEE ; Joung-Ho RHA ; Jee-Hyun KWON ; Sang Won HAN ; Bum Joon KIM ; Jaseong KOO ; Jay Chol CHOI ; Sang Min SUNG ; Soo Joo LEE ; Man-Seok PARK ; Seong Hwan AHN ; Oh Young BANG ; Yang-Ha HWANG ; Hyo Suk NAM ; Jong-Moo PARK ; Hee-Joon BAE ; Eung Gyu KIM ; Kyung-Yul LEE ; Mi Sun OH
Journal of Clinical Neurology 2021;17(3):344-353
Background:
and Purpose: Blood pressure (BP) control is strongly recommended, but BP control rate has not been well studied in patients with stroke. We evaluated the BP control rate with fimasartan-based antihypertensive therapy initiated in patients with recent cerebral ischemia.
Methods:
This multicenter, prospective, single-arm trial involved 27 centers in South Korea. Key inclusion criteria were recent cerebral ischemia within 90 days and high BP [systolic blood pressure (SBP) >140 mm Hg or diastolic blood pressure (DBP) >90 mm Hg]. BP lowering was initiated with fimasartan. BP management during the follow-up was at the discretion of the responsible investigators. The primary endpoint was the target BP goal achievement rate (<140/90 mm Hg) at 24 weeks. Key secondary endpoints included achieved BP and BP changes at each visit, and clinical events (ClinicalTrials.gov Identifier: NCT03231293).
Results:
Of 1,035 patients enrolled, 1,026 were included in the safety analysis, and 951 in the efficacy analysis. Their mean age was 64.1 years, 33% were female, the median time interval from onset to enrollment was 10 days, and the baseline SBP and DBP were 162.3±16.0 and 92.2±12.4 mm Hg (mean±SD). During the study period, 55.5% of patients were maintained on fimasartan monotherapy, and 44.5% received antihypertensive therapies other than fimasartan monotherapy at at least one visit. The target BP goal achievement rate at 24-week was 67.3% (48.6% at 4-week and 61.4% at 12-week). The mean BP was 139.0/81.8±18.3/11.7, 133.8/79.2±16.4/11.0, and 132.8/78.5±15.6/10.9 mm Hg at 4-, 12-, and 24-week. The treatment-emergent adverse event rate was 5.4%, including one serious adverse event.
Conclusions
Fimasartan-based BP lowering achieved the target BP in two-thirds of patients at 24 weeks, and was generally well tolerated.
7.Percutaneous Left Atrial Appendage Occlusion Yields Favorable Neurological Outcomes in Patients with Non-Valvular Atrial Fibrillation
Oh-Hyun LEE ; Young Dae KIM ; Jung-Sun KIM ; Nak-Hoon SON ; Hui-Nam PAK ; Boyoung JOUNG ; Cheol-Woong YU ; Hyun-Jong LEE ; Woong-Chol KANG ; Eun-Seok SHIN ; Rak-kyeong CHOI ; Do-Sun LIM ; Yo Han JUNG ; Hye-Yeon CHOI ; Kyung-Yul LEE ; Bang-Hoon CHO ; Sang Won HAN ; Joong Hyun PARK ; Han-Jin CHO ; Hyung Jong PARK ; Hyo Suk NAM ; Ji Hoe HEO ; Chak-yu SO ; Gary Shing-Him CHEUNG ; Yat-yin LAM ; Xavier FREIXA ; Apostolos TZIKAS ; Yangsoo JANG ; Jai-Wun PARK
Korean Circulation Journal 2021;51(7):626-638
Background and Objectives:
Prior studies have shown that stroke patients treated with percutaneous left atrial appendage occlusion (LAAO) for non-valvular atrial fibrillation (NVAF) experience better outcomes than similar patients treated with warfarin. We investigated the impact of percutaneous left atrial appendage closure on post-stroke neurological outcomes in NVAF patients, compared with non-vitamin K antagonist oral anticoagulant (NOAC) therapy.
Methods:
Medical records for 1,427 patients in multiple registries and for 1,792 consecutive patients at 6 Korean hospitals were reviewed with respect to LAAO or NOAC treatment.Stroke severity in patients who experienced ischemic stroke or transient ischemic attack after either treatment was assessed with modified Rankin Scale (mRS) scoring at hospital discharge and at 3 and 12 months post-stroke.
Results:
mRS scores were significantly lower in LAAO patients at 3 (p<0.01) and 12 months (p<0.01) post-stroke, despite no significant differences in scores before the ischemic cerebrovascular event (p=0.22). The occurrences of disabling ischemic stroke in the LAAO and NOAC groups were 36.7% and 44.2% at discharge (p=0.47), 23.3% and 44.2% at 3 months post-stroke (p=0.04), and 13.3% and 43.0% at 12 months post-stroke (p=0.01), respectively.Recovery rates for disabling ischemic stroke at discharge to 12 months post-stroke were significantly higher for LAAO patients (50.0%) than for NOAC patients (5.6%) (p<0.01).
Conclusions
Percutaneous LAAO was associated with more favorable neurological outcomes after ischemic cerebrovascular event than NOAC treatment.
8.Cataract Surgery Practice in the Republic of Korea: A Survey of the Korean Society of Cataract and Refractive Surgery 2020
Chang Rae RHO ; Jin-Hyoung KIM ; In Kwon CHUNG ; Eun Chol KIM ; Young Keun HAN ; Sang Youp HAN ; Youngsub EOM ; Tae-Young CHUNG ; Do-Hyung LEE
Korean Journal of Ophthalmology 2021;35(4):272-279
Purpose:
To describe current cataract surgery practice patterns and trends among Korean ophthalmologists.
Methods:
A survey was conducted among members of the Korean Society of Cataract and Refractive Surgery in October 2020. Of the 998 questionnaires, 262 (26.3%) were received for analysis. Data were analyzed using descriptive statistics and compared with those of previous surveys.
Results:
The largest percentage of respondents (39%) had <5 years of practical experience, and 40% had >11 years of practical experience. The average, median, and mode monthly volumes of cataract surgeries performed by the Korean Society of Cataract and Refractive Surgery members were 31, 20, and 10 cases, respectively. Topical anesthesia was administered by 85% of the respondents. For intraocular lens (IOL) calculations, 96% of the respondents used optical biometry. The proportion of surgeons providing femtosecond laser-assisted cataract surgery increased significantly from 5% in 2018 to 29% in 2020. This increase was accompanied by an increase in the multifocal IOLs. Those who implant multifocal IOL for >10% of their cases increased from 16% (2018) to 29% (2020). Topical nonsteroidal anti-inflammatory drugs were prescribed postoperatively by 76% of the respondents. Most respondents (70%) prescribed these anti-inflammatory drugs for 4 weeks.
Conclusions
This survey provided a comprehensive update on current cataract surgery practice in the Republic of Korea. The results highlighted the increasing use of premium IOLs, femtosecond laser-assisted cataract surgery, optical biometry, and topical anesthesia to better meet the patients’ needs.
9.Changes in Aerobic Capacity Over Time in Elderly Patients With Acute Myocardial Infarction During Cardiac Rehabilitation
Ki-Hong KIM ; Yun-Chol JANG ; Min-Keun SONG ; Hyeng-Kyu PARK ; In-Sung CHOI ; Jae-Young HAN
Annals of Rehabilitation Medicine 2020;44(1):77-84
Objective:
To test the hypothesis that a longer duration of phase II cardiac rehabilitation is required to recover the exercise capacity of elderly patients compared to younger patients.
Methods:
We retrospectively reviewed and analyzed the medical records of patients who were referred to our cardiac rehabilitation (CR) center and underwent percutaneous coronary intervention for acute myocardial infarction (AMI). A total of 70 patients were enrolled who underwent an exercise tolerance test (ETT) 3 weeks after the occurrence of an AMI (T0), 6 weeks after the first ETT (T1), and 12 weeks after the first ETT (T2). Patients older than 65 years were assigned to the elderly group (n=24) and those aged 65 years and younger to the younger group (n=46). Both groups performed center-based or home-based CR for 12 weeks (3 times per week and 1 session per day). Exercise intensity for each individual was based on the target heart rate calculated by the Karvonen formula. The change in maximal metabolic equivalents (METmax) of the two groups was measured at each assessment point (T0, T1, and T2) to investigate the recovery of exercise capacity.
Results:
The younger group showed improvement in METmax between T0 and T1. However, METmax of the elderly group showed no significant improvement between T0 and T1. The exercise capacity, measured with METmax, of all groups showed improvement between T0 and T2.
Conclusion
Elderly patients with AMI need a longer duration of CR (>6 weeks) than younger patients with AMI.
10.Validation of the 8th AJCC Cancer Staging System for Pancreas Neuroendocrine Tumors Using Korean Nationwide Surgery Database
Yunghun YOU ; Jin Young JANG ; Song Cheol KIM ; Yoo Seok YOON ; Joon Seong PARK ; Chol Kyoon CHO ; Sang Jae PARK ; Jae Do YANG ; Woo Jung LEE ; Tae Ho HONG ; Keun Soo AHN ; Chi Young JEONG ; Hyeon Kook LEE ; Seung Eun LEE ; Young Hoon ROH ; Hee Joon KIM ; Hongbeom KIM ; In Woong HAN
Cancer Research and Treatment 2019;51(4):1639-1652
PURPOSE: The 8th edition of the American Joint Committee on Cancer (AJCC) staging system for pancreatic neuroendocrine tumor (PNET) included several significant changes. We aim to evaluate this staging system compared to the 7th edition AJCC staging system and European Neuroendocrine Tumors Society (ENETS) system. MATERIALS AND METHODS: We used Korean nationwide surgery database (2000-2014). Of 972 patients who had undergone surgery for PNET, excluding patients diagnosed with ENETS/World Health Organization 2010 grade 3 (G3), only 472 patients with accurate stage were included. RESULTS: Poor discrimination in overall survival rate (OSR) was noted between AJCC 8th stage III and IV (p=0.180). The disease-free survival (DFS) curves of 8th AJCC classification were well separated between all stages. Compared with stage I, the hazard ratio of II, III, and IV was 3.808, 13.928, and 30.618, respectively (p=0.007, p < 0.001, and p < 0.001). The curves of OSR and DFS of certain prognostic group in AJCC 7th and ENETS overlapped. In ENETS staging system, no significant difference in DFS between stage IIB versus IIIA (p=0.909) and IIIA versus IIIB (p=0.291). In multivariable analysis, lymphovascular invasion (p=0.002), perineural invasion (p=0.003), and grade (p < 0.001) were identified as independent prognostic factors for DFS. CONCLUSION: This is the first large-scale validation of the AJCC 8th edition staging system for PNET. The revised 8th system provides better discrimination compared to that of the 7th edition and ENETS TNM system. This supports the clinical use of the system.
Classification
;
Discrimination (Psychology)
;
Disease-Free Survival
;
Humans
;
Joints
;
Neoplasm Staging
;
Neuroectodermal Tumors, Primitive
;
Neuroendocrine Tumors
;
Pancreas
;
Survival Rate

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