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Hanyang University Medical Center

Hospital / health systemSeoul, Seoul, South Korea

Research output, citation impact, and the most-cited recent papers from Hanyang University Medical Center (South Korea). Aggregated across the NobleBlocks index of 300M+ scholarly works.

Total works
1.7K
Citations
56.9K
h-index
97
i10-index
1.4K
Also known as
Hanyang University Medical Center한양대학교의료원

Top-cited papers from Hanyang University Medical Center

Prevalence of non-alcoholic fatty liver disease and risk factors for advanced fibrosis and mortality in the United States
Michael H. Le, Pardha Devaki, Nghiem B. Ha, Dae Won Jun +3 more
2017· PLoS ONE289doi:10.1371/journal.pone.0173499

In the United States, non-alcoholic fatty liver disease (NAFLD) is the most common liver disease and associated with higher mortality according to data from earlier National Health and Nutrition Examination Survey (NHANES) 1988-1994. Our goal was to determine the NAFLD prevalence in the recent 1999-2012 NHANES, risk factors for advanced fibrosis (stage 3-4) and mortality. NAFLD was defined as having a United States Fatty Liver Index (USFLI) > 30 in the absence of heavy alcohol use and other known liver diseases. The probability of low/high risk of having advanced fibrosis was determined by the NAFLD Fibrosis Score (NFS). In total, 6000 persons were included; of which, 30.0% had NAFLD and 10.3% of these had advanced fibrosis. Five and eight-year overall mortality in NAFLD subjects with advanced fibrosis was significantly higher than subjects without NAFLD ((18% and 35% vs. 2.6% and 5.5%, respectively) but not NAFLD subjects without advanced fibrosis (1.1% and 2.8%, respectively). NAFLD with advanced fibrosis (but not those without) is an independent predictor for mortality on multivariate analysis (HR = 3.13, 95% CI 1.93-5.08, p<0.001). In conclusion, in this most recent NHANES, NAFLD prevalence remains at 30% with 10.3% of these having advanced fibrosis. NAFLD per se was not a risk factor for increased mortality, but NAFLD with advanced fibrosis was. Mexican American ethnicity was a significant risk factor for NAFLD but not for advanced fibrosis or increased mortality.

Development and Validation of a Deep Learning System for Staging Liver Fibrosis by Using Contrast Agent–enhanced CT Images in the Liver
Kyu Jin Choi, Jong Keon Jang, Seung Soo Lee, Yu Sub Sung +4 more
2018· Radiology209doi:10.1148/radiol.2018180763

Purpose To develop and validate a deep learning system (DLS) for staging liver fibrosis by using CT images in the liver. Materials and Methods DLS for CT-based staging of liver fibrosis was created by using a development data set that included portal venous phase CT images in 7461 patients with pathologically confirmed liver fibrosis. The diagnostic performance of the DLS was evaluated in separate test data sets for 891 patients. The influence of patient characteristics and CT techniques on the staging accuracy of the DLS was evaluated by logistic regression analysis. In a subset of 421 patients, the diagnostic performance of the DLS was compared with that of the radiologist's assessment, aminotransferase-to-platelet ratio index (APRI), and fibrosis-4 index by using the area under the receiver operating characteristic curve (AUROC) and Obuchowski index. Results In the test data sets, the DLS had a staging accuracy of 79.4% (707 of 891) and an AUROC of 0.96, 0.97, and 0.95 for diagnosing significant fibrosis (F2-4), advanced fibrosis (F3-4), and cirrhosis (F4), respectively. At multivariable analysis, only pathologic fibrosis stage significantly affected the staging accuracy of the DLS (P = .016 and .013 for F1 and F2, respectively, compared with F4), whereas etiology of liver disease and CT technique did not. The DLS (Obuchowski index, 0.94) outperformed the radiologist's interpretation, APRI, and fibrosis-4 index (Obuchowski index range, 0.71-0.81; P ˂ .001) for staging liver fibrosis. Conclusion The deep learning system allows for accurate staging of liver fibrosis by using CT images. © RSNA, 2018 Online supplemental material is available for this article.

Randomized, Double-blind, Placebo-controlled Study of a Multispecies Probiotic Mixture in Nonalcoholic Fatty Liver Disease
Sang Bong Ahn, Dae Won Jun, Bo-Kyeong Kang, Jong Hyun Lim +2 more
2019· Scientific Reports206doi:10.1038/s41598-019-42059-3

The intestinal microbiota is closely associated with the development of obesity and nonalcoholic fatty liver disease (NAFLD). This study investigated the effects of probiotic treatment on visceral fat area (VFA) and intrahepatic fat (IHF) fraction in NAFLD. Sixty-eight obese NAFLD patients (>5% proton density fat fraction [PDFF] on magnetic resonance imaging [MRI]) were randomized to probiotic and placebo groups for 12 weeks. The probiotic mixture included 6 bacterial species. VFA and IHF were measured using the MRI-PDFF technique. Body weight and total body fat were reduced in the probiotic group but not in the placebo group. The mean IHF fraction was reduced after 12 weeks of treatment in the probiotic group compared to that at baseline (from 16.3 ± 15.0% to 14.1 ± 7.7%, p = 0.032) but was not reduced in the placebo group. The decrease in IHF (mean difference: -2.61%, p = 0.012) was also greater in the probiotic group than in the placebo group. Reduction of triglyceride was greater in the probiotic treatment group than in the placebo group (mean difference: -34.0 mg/dl, p = 0.0033). However, the changes in IHF percentage and triglyceride levels were not different between placebo and control groups after adjusting for changes in body weight. Treatment with probiotics for 12 weeks resulted in significant reduction in IHF and body weight in obese NAFLD patients.

The Effect of Synthetic Osteoconductive Bone Graft Material for Augmentation of Internally Fixed Unstable Trochanteric Fractures
Jin Myung Park, Jung Min Shin, Do Kyung Lee, Sung‐Sahn Lee +2 more
2019· BioMed Research International199doi:10.1155/2019/5879089

This study aimed to evaluate whether the augmentation of CaP into the femoral head around the lag screw results in superior clinical and radiological outcomes of treatment of unstable trochanteric fractures using an intramedullary (IM) implant. Fifty-six consecutive patients with unstable trochanteric fractures who had been surgically treated with IM devices between 2014 and 2016 were prospectively reviewed and randomly divided into two groups based on the use of CaP degradable cements: 28 patients were assigned to the CaP group, while the other 28 patients were assigned to the control group (no use of CaP). Clinical evaluations and radiological analyses were conducted during a minimum of 2-year follow-up. No significant differences in the mean visual analogue scale for the hip pain scores and modified Harris Hip Scores were found between the CaP group and the controls at postoperative 2 months and 2 years. However, earlier walker ambulation was possible in the CaP group (10 ± 9 days) compared to the control group (13 ± 12 days) (P = 0.02). In radiological analysis, the CaP group showed significantly lower difference between tip-apex distance measured immediately after surgery and that measured at one-year follow-up compared to the control group (P = 0.012). No screw cut-out occurred in the CaP group, while one patient in the control group was reoperated for screw cut-out. The CaP augmentation into the femoral head around lag screw can reduce lag screw penetration, prevent screw cut-out beyond the femoral head, and facilitate early ambulation in elderly patients with unstable trochanteric fractures.

Autoantibodies and neuropsychiatric events at the time of systemic lupus erythematosus diagnosis: Results from an international inception cohort study
John G. Hanly, Murray B. Urowitz, Fotios Siannis, Vernon T. Farewell +4 more
2008· Arthritis & Rheumatism193doi:10.1002/art.23218

OBJECTIVE: To examine, in an inception cohort of systemic lupus erythematosus (SLE) patients, the association between neuropsychiatric (NP) events and anti-ribosomal P (anti-P), antiphospholipid (lupus anticoagulant [LAC], anticardiolipin), anti-beta2-glycoprotein I, and anti-NR2 glutamate receptor antibodies. METHODS: NP events were identified using the American College of Rheumatology case definitions and clustered into central/peripheral and diffuse/focal events. Attribution of NP events to SLE was determined using decision rules of differing stringency. Autoantibodies were measured without knowledge of NP events or their attribution. RESULTS: Four hundred twelve patients were studied (87.4% female; mean +/- SD age 34.9 +/- 13.5 years, mean +/- SD disease duration 5.0 +/- 4.2 months). There were 214 NP events in 133 patients (32.3%). The proportion of NP events attributed to SLE varied from 15% to 36%. There was no association between autoantibodies and NP events overall. However, the frequency of anti-P antibodies in patients with central NP events attributed to SLE was 4 of 20 (20%), versus 3 of 107 (2.8%) in patients with other NP events and 24 of 279 (8.6%) in those with no NP events (P = 0.04). Among patients with diffuse NP events, 3 of 11 had anti-P antibodies (27%), compared with 4 of 111 patients with other NP events (3.6%) and 24 of 279 of those with no NP events (8.6%) (P = 0.02). Specific clinical-serologic associations were found between anti-P and psychosis attributed to SLE (P = 0.02) and between LAC and cerebrovascular disease attributed to SLE (P = 0.038). There was no significant association between other autoantibodies and NP events. CONCLUSION: Clinically distinct NP events attributed to SLE and occurring around the time of diagnosis were found to be associated with anti-P antibodies and LAC. This suggests that there are different autoimmune pathogenetic mechanisms, although low sensitivity limits the clinical application of testing for these antibodies.

Sensation of bloating and visible abdominal distension in patients with irritable bowel syndrome
Lin Chang, O. Y. Lee, Bruce Naliboff, Max J. Schmulson +1 more
2001· The American Journal of Gastroenterology191doi:10.1111/j.1572-0241.2001.05336.x

OBJECTIVES: Abdominal bloating and distension are common symptoms of irritable bowel syndrome (IBS). The postulated pathophysiological mechanisms underlying these symptoms include increased production, retention, or perception of gas or luminal contents. The aims of this study were to prospectively compare the prevalence of, and clinical factors related to, bloating and distension in an IBS patient population. METHODS: A total of 714 consecutive patients who met Rome I criteria for IBS were prospectively surveyed, and were classified as having bloating alone (B) or bloating and distension (B+D) based on a comprehensive bowel symptom questionnaire. GI, extraintestinal, and psychological symptoms, as well as health-related quality of life measures were also assessed using validated survey instruments. RESULTS: A total of 542 IBS patients (76%) who reported abdominal bloating were studied. Of these, 132 patients fulfilled criteria for the B group, whereas 410 patients fulfilled criteria for the B+D group. There was a significantly different gender distribution in the B and B+D groups (female:male ratios, 1.4:1 and 2.8:1, respectively p < 0.02). There was also a significantly different bowel habit subgroup distribution, with a greater predominance of constipation in B+D group and of diarrhea in the B group (p < 0.03). Both groups were similar in other clinical parameters, including progressive worsening of symptoms during the day, and relief by passing stool or gas. Both bloating and distension worsened when other abdominal symptoms worsened. Abdominal distension was associated with greater symptom severity and less diurnal variation in symptoms, and was less often perceived as associated with food intake. CONCLUSIONS: Bloating and visible abdominal distension may arise from two distinct but interrelated physiological processes. Although the sensation of bloating may be related to enhanced sensitivity to visceral afferent stimulation, abdominal distension in more severely affected patients may be related to triggering of a visceromotor reflex affecting the tone of abdominal wall muscles.

Association of STAT4 with Rheumatoid Arthritis in the Korean Population
Hye‐Soon Lee, Elaine F. Remmers, Julie Le, Daniel L. Kastner +2 more
2007· Molecular Medicine180doi:10.2119/2007-00072.lee

A recent study in the North American White population has documented the association of a common STAT4 haplotype (tagged by rs7574865) with risk for rheumatoid arthritis (RA) and systemic lupus erythematosus. To replicate this finding in the Korean population, we performed a case-control association study. We genotyped 67 single nucleotide polymorphisms (SNPs) within the STAT1 and STAT4 regions in 1123 Korean patients with RA and 1008 ethnicity-matched controls. The most significant four risk SNPs (rs11889341, rs7574865, rs8179673, and rs10181656 located within the third intron of STAT4) among 67 SNPs are identical with those in the North American study. All four SNPs have modest risk for RA susceptibility (odds ratio 1.21-1.27). A common haplotype defined by these markers (TTCG) carries significant risk for RA in Koreans [34 percent versus 28 percent, P=0.0027, OR (95 percent CI)=1.33 (1.10-1.60)]. By logistic regression analysis, this haplotype is an independent risk factor in addition to the classical shared epitope alleles at the HLA-DRB1 locus. There were no significant associations with age of disease onset, radiographic progression, or serologic status using either allelic or haplotypic analysis. Unlike several other risk genes for RA such as PTPN22, PADI4, and FCRL3, a haplotype of the STAT4 gene shows consistent association with RA susceptibility across Whites and Asians, suggesting that this risk haplotype predates the divergence of the major racial groups.

Long-Term Exposure to Air Pollutants and Cancer Mortality: A Meta-Analysis of Cohort Studies
Hong-Bae Kim, Jae‐Yong Shim, Byoungjin Park, Yong‐Jae Lee
2018· International Journal of Environmental Research and Public Health164doi:10.3390/ijerph15112608

The aim of this study was to examine the relationship between main air pollutants and all cancer mortality by performing a meta-analysis. We searched PubMed, EMBASE (a biomedical and pharmacological bibliographic database of published literature produced by Elsevier), and the reference lists of other reviews until April 2018. A random-effects model was employed to analyze the meta-estimates of each pollutant. A total of 30 cohort studies were included in the final analysis. Overall risk estimates of cancer mortality for 10 µg/m3 per increase of particulate matter (PM)2.5, PM10, and NO2 were 1.17 (95% confidence interval (CI): 1.11–1.24), 1.09 (95% CI: 1.04–1.14), and 1.06 (95% CI: 1.02–1.10), respectively. With respect to the type of cancer, significant hazardous influences of PM2.5 were noticed for lung cancer mortality and non-lung cancer mortality including liver cancer, colorectal cancer, bladder cancer, and kidney cancer, respectively, while PM10 had harmful effects on mortality from lung cancer, pancreas cancer, and larynx cancer. Our meta-analysis of cohort studies indicates that exposure to the main air pollutants is associated with increased mortality from all cancers.

Proxy‐reported health‐related quality of life of patients with juvenile idiopathic arthritis: The pediatric rheumatology international trials organization multinational quality of life cohort study
Sheila Oliveira, Angelo Ravelli, Angela Pistorio, E Castell +4 more
2007· Arthritis Care & Research162doi:10.1002/art.22473

OBJECTIVE: To investigate the proxy-reported health-related quality of life (HRQOL) and its determinants in patients with juvenile idiopathic arthritis (JIA). METHODS: In this multinational, multicenter, cross-sectional study, HRQOL of patients with JIA was assessed through the Child Health Questionnaire (CHQ) and was compared with that of healthy children of similar age from the same geographic area. Potential determinants of HRQOL included demographic data, physician's and parent's global assessments, measures of joint inflammation, Childhood Health Assessment Questionnaire (CHAQ), and erythrocyte sedimentation rate. RESULTS: A total of 6,639 participants (3,324 with JIA and 3,315 healthy) were enrolled from 32 countries. The mean +/- SD physical and psychosocial summary scores of the CHQ were significantly lower in patients with JIA than in healthy children (physical: 44.5 +/- 10.6 versus 54.6 +/- 4.0, P < 0.0001; psychosocial: 47.6 +/- 8.7 versus 51.9 +/- 7.5, P < 0.0001), with the physical well-being domain being most impaired. Patients with persistent oligoarthritis had better HRQOL compared with other subtypes, whereas HRQOL was similar across patients with systemic arthritis, polyarthritis, and extended oligoarthritis. A CHAQ score >1 and a pain intensity rating >3.4 cm on a 10-cm visual analog scale were the strongest determinants of poorer HRQOL in the physical and psychosocial domains, respectively. CONCLUSION: We found that patients with JIA have a significant impairment of their HRQOL compared with healthy peers, particularly in the physical domain. Physical well-being was mostly affected by the level of functional impairment, whereas the intensity of pain had the greatest influence on psychosocial health.

Expert panel consensus recommendations for ambulatory blood pressure monitoring in Asia: The HOPE Asia Network
Kazuomi Kario, Jinho Shin, Chen‐Huan Chen, Peera Buranakitjaroen +4 more
2019· Journal of Clinical Hypertension158doi:10.1111/jch.13652

Hypertension is an important public health issue because of its association with a number of significant diseases and adverse outcomes. However, there are important ethnic differences in the pathogenesis and cardio-/cerebrovascular consequences of hypertension. Given the large populations and rapidly aging demographic in Asian regions, optimal strategies to diagnose and manage hypertension are of high importance. Ambulatory blood pressure monitoring (ABPM) is an important out-of-office blood pressure (BP) measurement tool that should play a central role in hypertension detection and management. The use of ABPM is particularly important in Asia due to the specific features of hypertension in Asian patients, including a high prevalence of masked hypertension, disrupted BP variability with marked morning BP surge, and nocturnal hypertension. This HOPE Asia Network document summarizes region-specific literature on the relationship between ABPM parameters and cardiovascular risk and target organ damage, providing a rationale for consensus-based recommendations on the use of ABPM in Asia. The aim of these recommendations is to guide and improve clinical practice to facilitate optimal BP monitoring with the goal of optimizing patient management and expediting the efficient allocation of treatment and health care resources. This should contribute to the HOPE Asia Network mission of improving the management of hypertension and organ protection toward achieving "zero" cardiovascular events in Asia.

Hepatitis B virus (HBV) reactivation in rheumatic patients with hepatitis core antigen (HBV occult carriers) undergoing anti-tumor necrosis factor therapy.
Young Ho Lee, Sang‐Cheol Bae, Gwan Gyu Song
2013· PubMed155

OBJECTIVES: The aim of this study was to assess the effects of anti-tumour necrosis factor (TNF) agents on hepatitis B virus (HBV) reactivation in hepatitis B surface antigen (HBsAg)-negative and anti-hepatitis B core (HBc)-positive patients (HBV occult carriers) with rheumatic diseases. METHODS: Evidence of HBV reactivation after anti-TNF therapy in HBV occult carriers with a rheumatic disease was studied by summarising results and by performing meta-analysis analysis. RESULTS: A total of 468 HBsAg-negative and anti-HBc-positive patients with a rheumatic disease undergoing treatment with an anti-TNF agent were identified in nine studies. The anti-TNF agents used were etanercept in 269 cases, adalimumab in 95, and infliximab in 100 cases, and these were administered for rheumatoid arthritis (RA) in 327 patients, ankylosing spondylitis in 49, and psoriatic arthritis (PsA) in 73 patients. Follow-up periods ranged from 6 to 60 months. HBV reactivation in patients on an anti-TNF agent was reported in 8 cases (8/468 = 1.7%). Seven of these patients had RA and 1 had PsA. Seven patients received etanercept and one adalimumab. HBV-DNA was detectable in 7 of these 8 cases. Antiviral treatment was administered in 6 of the 8 (lamivudine in 2, entecavir in 4) and clinical outcomes were satisfactory in all 8 patients. CONCLUSIONS: HBV reactivation was found in 8 (1.7%) patients among 468 HBsAg-negative and anti-HBc-positive patients with rheumatic diseases treated with anti-TNF agents. Our data suggest that HBsAg-negative and anti-HBc-positive patients undergoing anti-TNF therapy need to be carefully monitored during anti-TNF therapy.

Hypertension and stroke in Asia: A comprehensive review from HOPE Asia
Yuda Turana, Jeslyn Tengkawan, Yook Chin Chia, Michael Nathaniel +4 more
2020· Journal of Clinical Hypertension154doi:10.1111/jch.14099

Stroke is the primary cause of disability and vascular death worldwide, including Asia. Asian characteristics that differ from the West lead to higher stroke incidence. Stroke epidemiology studies in Asia have shown varying levels of mortality, incidence, prevalence, and burden of disease. Hypertension is the most prevalent risk factor found in Asia. Besides ethnicity that is associated with stroke incidence, both systolic blood pressure, diastolic blood pressure, and blood pressure variability are positively correlated with stroke incidence. Post-stroke cognitive impairment is one of the sequelae that affect one-third of stroke survivors and has become a significant public health concern that is often neglected despite its increasing prevalence. Therefore, it is very important to prevent recurrence by treating stroke optimally and effectively. Increasing awareness and treatment adherence to hypertension, the leading risk factor for stroke, became the main goal in several countries in Asia.

The 2022 focused update of the 2018 Korean Hypertension Society Guidelines for the management of hypertension
Hack‐Lyoung Kim, Eun Mi Lee, Shin Young Ahn, Kwang‐Il Kim +4 more
2023· Clinical Hypertension148doi:10.1186/s40885-023-00234-9

Hypertension is the leading cause of death in human being, which shows high prevalence and associated complications that increase the mortality and morbidity. Controlling blood pressure (BP) is very important because it is well known that lowering high BP effectively improves patients' prognosis. This review aims to provide a focused update of the 2018 Korean Hypertension Society Guidelines for the management of hypertension. The importance of ambulatory BP and home BP monitoring was further emphasized not only for the diagnosis but also for treatment target. By adopting corresponding BPs, the updated guideline recommended out-of-office BP targets for both standard and intensive treatment. Based on the consensus on corresponding BPs and Systolic Blood Pressure Intervention Trial (SPRINT) revisit, the updated guidelines recommended target BP in high-risk patients below 130/80 mmHg and it applies to hypertensive patients with three or more additional cardiovascular risk factors, one or more risk factors with diabetes, or hypertensive patients with subclinical organ damages, coronary or vascular diseases, heart failure, chronic kidney disease with proteinuria, and cerebral lacunar infarction. Cerebral infarction and chronic kidney disease are also high-risk factors for cardiovascular disease. However, due to lack of evidence, the target BP was generally determined at < 140/90 mmHg in patients with those conditions as well as in the elderly. Updated contents regarding the management of hypertension in special situations are also discussed.

MR Enterography for the Evaluation of Small-Bowel Inflammation in Crohn Disease by Using Diffusion-weighted Imaging without Intravenous Contrast Material: A Prospective Noninferiority Study
Nieun Seo, Seong Ho Park, Kyung‐Jo Kim, Bo-Kyeong Kang +4 more
2015· Radiology147doi:10.1148/radiol.2015150809

PURPOSE: To determine whether magnetic resonance (MR) enterography performed with diffusion-weighted imaging (DWI) without intravenous contrast material is noninferior to contrast material-enhanced (CE) MR enterography for the evaluation of small-bowel inflammation in Crohn disease. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained for this prospective noninferiority study. Fifty consecutive adults suspected of having Crohn disease underwent clinical assessment, MR enterography, and ileocolonoscopy within 1 week. MR enterography included conventional imaging and DWI (b = 900 sec/mm(2)). In 44 patients with Crohn disease, 171 small-bowel segments that were generally well distended and showed a wide range of findings, from normalcy to severe inflammation (34 men, 10 women; mean age ± standard deviation, 26.9 years ± 6.1), were selected for analysis. Image sets consisting of (a) T2-weighted sequences with DWI and (b) T2-weighted sequences with CE T1-weighted sequences were reviewed by using a crossover design with blinding and randomization. Statistical analyses included noninferiority testing regarding proportional agreement between DWI and CE MR enterography for the identification of bowel inflammation with a noninferiority margin of 80%, correlation between DWI and CE MR enterography scores of bowel inflammation severity, and comparison of accuracy between DWI and CE MR enterography for the diagnosis of terminal ileal inflammation by using endoscopic findings as the reference standard. RESULTS: The agreement between DWI and CE MR enterography for the identification of bowel inflammation was 91.8% (157 of 171 segments; one-sided 95% confidence interval: ≥88.4%). The correlation coefficient between DWI and CE MR enterography scores was 0.937 (P < .001). DWI and CE MR enterography did not differ significantly regarding the sensitivity and specificity for the diagnosis of terminal ileal inflammation (P > .999). DWI and CE MR enterography concurred in the diagnosis of penetrating complications in five of eight segments. CONCLUSION: DWI MR enterography was noninferior to CE MR enterography for the evaluation of inflammation in Crohn disease in generally well-distended small bowel, except for the diagnosis of penetration.

Checkpoint-apoptosis uncoupling in human and mouse embryonic stem cells: a source of karyotpic instability
Charlie Mantel, Ying Guo, Man Ryul Lee, Min-Kyoung Kim +4 more
2007· Blood140doi:10.1182/blood-2006-10-054247

Karyotypic abnormalities in cultured embryonic stem cells (ESCs), especially near-diploid aneuploidy, are potential obstacles to ESC use in regenerative medicine. Events causing chromosomal abnormalities in ESCs may be related to events in tumor cells causing chromosomal instability (CIN) in human disease. However, the underlying mechanisms are unknown. Using multiparametric permeabilized-cell flow cytometric analysis, we found that the mitotic-spindle checkpoint, which helps maintain chromosomal integrity during all cell divisions, functions in human and mouse ESCs, but does not initiate apoptosis as it does in somatic cells. This allows an unusual tolerance to polyploidy resulting from failed mitosis, which is common in rapidly proliferating cell populations and which is reduced to near-diploid aneuploidy, which is also common in human neoplastic disease. Checkpoint activation in ESC-derived early-differentiated cells results in robust apoptosis without polyploidy/aneuploidy similar to that in somatic cells. Thus, the spindle checkpoint is "uncoupled" from apoptosis in ESCs and is a likely source of karyotypic abnormalities. This natural behavior of ESCs to tolerate/survive varying degrees of ploidy change could complicate genome-reprogramming studies and stem-cell plasticity studies, but could also reveal clues about the mechanisms of CIN in human tumors.

Mesenchymal stem cells' interaction with skin: Wound-healing effect on fibroblast cells and skin tissue
Young Keul Jeon, Yun Ho Jang, Dong Ryeol Yoo, Si Na Kim +2 more
2010· Wound Repair and Regeneration133doi:10.1111/j.1524-475x.2010.00636.x

Mesenchymal stem cells (MSCs) are multipotent progenitor cells with the ability to secrete growth factors. Because wound healing is associated with fibroblast cells and extracellular matrix (ECM) in the dermis and epidermis, we used fibroblast cells to resolve the question of whether or not MSCs regulate wound healing in vitro via a regenerative function. Using a cell proliferation assay, we demonstrated that conditioned media (CM) obtained from MSCs significantly enhanced the cell survival ability of fibroblast cells. Moreover, by measurement of mRNA and protein, we observed that CM also promoted the production or secretion of collagen, elastin, and fibronectin. To better understand the effects of ECM-related wound healing, we measured the level of collagen-degradative enzyme (matrix metalloprotease-1), and observed that CM suppressed matrix metalloprotease-1 expression. For the determination of oxidative stress, which has an influence on wound healing, we performed the superoxide dismutase and glutathione peroxidase assays; our results suggested that CM inhibited the oxidative stress of fibroblast cells. In order to widely investigate the wound-healing effects of MSCs, we performed in vivo experiments, and observed that MSCs stimulated wound healing. In summary, the results of this study suggest that MSCs inhibit the loss of fibroblast cells and ECM, and accumulation of oxidative stress. We found that MSCs stimulate wound healing in vitro and in vivo, suggesting that MSCs have the potential to enhance wound healing.

Phytosphingosine in combination with ionizing radiation enhances apoptotic cell death in radiation-resistant cancer cells through ROS-dependent and -independent AIF release
Moon-Taek Park, Min-Jung Kim, Young-Hee Kang, Soon-Young Choi +4 more
2004· Blood128doi:10.1182/blood-2004-07-2938

The use of chemical modifiers as radiosensitizers in combination with low-dose irradiation may increase the therapeutic effect on cancer by overcoming a high apoptotic threshold. Here, we showed that phytosphingosine treatment in combination with gamma-radiation enhanced apoptotic cell death of radiation-resistant human T-cell lymphoma in a caspase-independent manner. Combination treatment induced an increase in intracellular reactive oxygen species (ROS) level, mitochondrial relocalization of B-cell lymphoma-2(Bcl-2)-associated X protein (Bax), poly-adenosine diphosphate (ADP)-ribose polymerase 1 (PARP-1) activation, and nuclear translocation of apoptosis-inducing factor (AIF). siRNA targeting of AIF effectively protected cells from the combination treatment-induced cell death. An antioxidant, N-acetyl-L-cysteine (NAC), inhibited Bax relocalization and AIF translocation but not PARP-1 activation. Moreover, transfection of Bax-siRNA significantly inhibited AIF translocation. Pretreatment of PARP-1 inhibitor, DPQ (3,4-dihydro-5-[4-(1-piperidinyl)-butoxy]-1(2H)-isoquinolinone), or PARP-1-siRNA also partially attenuated AIF translocation, whereas the same treatment did not affect intracellular ROS level and Bax redistribution. Taken together, these results demonstrate that enhancement of cell death of radiation-resistant cancer cells by phytosphingosine treatment in combination with gamma-radiation is mediated by nuclear translocation of AIF, which is in turn mediated both by ROS-dependent Bax relocalization and ROS-independent PARP-1 activation. The molecular signaling pathways that we elucidated in this study may provide potential drug targets for radiation sensitization of cancers refractive to radiation therapy.

Reliability and validity of systemic lupus activity measure-revised (SLAM-R) for measuring clinical disease activity in systemic lupus erythematosus
S-C Bae, H-K Koh, D-K Chang, M-H Kim +2 more
2001· Lupus127doi:10.1191/096120301678646146

New clinical scales for semiquantitating disease activity in systemic lupus erythematosus (SLE) are widely used in research. They are reliable and valid measures. One of the original scales, the Systemic Lupus Activity Measure (SLAM), has been modified based on experience with it in multi-observer studies and training of individuals in its use. We tested the psychometric properties of the revised SLAM (SLAM-R). SLAM-R was tested on 30 SLE patients, who fulfilled 1997 revised ACR criteria and were selected to represent a range of disease activity. The patients were evaluated independently by two physicians, who studied the instruction booklet and who had never used SLAM-R, on two occasions 2-4 weeks apart. At the first visit, the physician's global assessment of activity using visual analog scale, anti-dsDNA Ab, C3 and C4 were checked for construct validity. The psychometric properties were analyzed with nested analysis of variance and Pearson's correlation coefficient using SAS. All patients were female, the median age was 31 (15-52) y, and the mean score of SLAM-R was 10.5 +/- 5.3 (3-26). Estimates of reliability were 0.78 of inter-rater, 0.61 of inter-visit, 0.76 of physician 1 between visits, and 0.56 of physician 2 between visits. Among subcategories except 'Eye,' the 'Gastrointestinal' category had the highest (0.96) and the 'Neuromotor' category had the lowest inter-rater reliability (0.50). With respect to construct validity, the correlation of SLAM-R scores with the disease activity variables except C4 was high and statistically significant. In conclusion, the SLAM-R is reliable and valid for measuring clinical disease activity in SLE.

Matching into Integrated Plastic Surgery: The Value of Research Fellowships
Karan Mehta, Sammy Sinno, Vishal Thanik, Katie E. Weichman +2 more
2018· Plastic & Reconstructive Surgery126doi:10.1097/prs.0000000000005212

BACKGROUND: Integrated plastic surgery residency applicants sometimes complete research fellowships before residency. The average productivity and the impact of these fellowships on subsequent application to residency are unknown. The purpose of this study was to provide objective data to better understand the utility and productivity of a research fellowship. METHODS: A national survey was conducted in which integrated plastic surgery residency applicants from 2013 to 2016 were surveyed regarding their experiences with research fellowships. American Council of Academic Plastic Surgeons members were also surveyed to elicit their perspectives on the value of these fellowships. RESULTS: Six hundred twenty-one integrated plastic surgery applicants from 2013 to 2016 were included in the study. Twenty-five percent of applicants participated in a research fellowship. Applicants who completed research fellowships were more likely to match into plastic surgery compared to those who did not (97 percent versus 81 percent, respectively; p < 0.05). Fellows were highly satisfied with their fellowship experience and produced an average of five publications and presentations per fellowship year. Sixty-three percent of research fellowships were performed to strengthen applications to categorical integrated plastic surgery residency. American Council of Academic Plastic Surgeons members considered three or four publications/presentations productive. Most do not recommend research fellowships to all medical students. CONCLUSIONS: Research fellowships can effectively prepare for categorical plastic surgery by improving publication and presentation experience. This is the first study to show that applicants who completed research fellowships were highly satisfied with their experience, accomplished higher than expected levels of productivity, and statistically significantly matched into an integrated plastic surgery residency more often than applicants without research fellowships.

Seizures and Epilepsy following Aneurysmal Subarachnoid Hemorrhage : Incidence and Risk Factors
Kyu-Sun Choi, Hyoung-Joon Chun, Hyeong-Joong Yi, Yong Ko +2 more
2009· Journal of Korean Neurosurgical Society123doi:10.3340/jkns.2009.46.2.93

OBJECTIVE: Although prophylactic antiepileptic drug (AED) use in patients with aneurysmal subarachnoid hemorrhage (SAH) is a common practice, lack of uniform definitions and guidelines for seizures and AEDs rendered this prescription more habitual instead of evidence-based manner. We herein evaluated the incidence and predictive factors of seizure and complications about AED use. METHODS: From July 1999 to June 2007, data of a total of 547 patients with aneurysmal SAH who underwent operative treatments were reviewed. For these, the incidence and risk factors of seizures and epilepsy were assessed, in addition to complications of AEDs. RESULTS: Eighty-three patients (15.2%) had at least one seizure following SAH. Forty-three patients (7.9%) had onset seizures, 34 (6.2%) had perioperative seizures, and 17 (3.1%) had late epilepsy. Younger age (< 40 years), poor clinical grade, thick hemorrhage, acute hydrocephalus, and rebleeding were related to the occurrence of onset seizures. Cortical infarction and thick hemorrhage were independent risk factors for the occurrence of late epilepsy. Onset seizures were not predictive of late epilepsy. Moreover, adverse drug effects were identified in 128 patients (23.4%) with AEDs. CONCLUSION: Perioperative seizures are not significant predictors for late epilepsy. Instead, initial amount of SAH and surgery-induced cortical damage should be seriously considered as risk factors for late epilepsy. Because AEDs can not prevent early postoperative seizures (< 1 week) and potentially cause unexpected side effects, long-term use should be readjusted in high-risk patients.