Search tips
Search criteria

Results 1-25 (42)

Clipboard (0)

Select a Filter Below

Year of Publication
more »
1.  Feasibility of α-fetoprotein as a diagnostic tool for hepatocellular carcinoma in Korea 
The aim of this study was to evaluate the feasibility of α-fetoprotein (AFP) as a diagnostic tool for hepatocellular carcinoma (HCC) in Korean patients.
We retrospectively reviewed the medical records of HCC and cirrhosis patients at three hospitals. For each HCC patient, a cirrhosis patient matched for age, sex, etiology, and Child-Pugh classification was selected by simple random sampling. The performance of AFP in the diagnosis of HCC was determined using receiver operating characteristic curve analysis.
A total of 732 patients with HCC or cirrhosis were selected for each case and the control groups. The mean age was 54 years, and 72.4% of patients were male. The mean serum AFP levels in the HCC group and cirrhosis group were 3,315.6 and 117.2 ng/mL, respectively (p < 0.001). The area under the receiver operating characteristic curve for all HCC patients was 0.757. The sensitivity, specificity, and positive predictive value of AFP was 50.55%, 87.70%, and 80.43%, respectively, at a cut-off of 20 ng/mL; 37.70%, 95.90%, and 90.20%, respectively, at a cut-off of 100 ng/mL, and 30.05%, 97.27%, and 91.67%, respectively, at a cut-off of 200 ng/mL. A cut-off of 100 ng/mL was more sensitive than one of 200 ng/mL with equivalent specificity and positive predictive value.
The cut-off AFP value for early-stage HCC was 17.4 ng/mL. Our study cautiously suggests that AFP has a role in the diagnosis of HCC, and that the appropriate value of AFP for the diagnosis of HCC may be 100 ng/mL rather than 200 ng/mL.
PMCID: PMC4712434  PMID: 26767857
Alpha-fetoproteins; Carcinoma; Diagnosis; Hepatocellular
2.  Surgical Anatomy of the Uncinate Process and Transverse Foramen Determined by Computed Tomography 
Global Spine Journal  2015;5(5):383-390.
Study Design Computed tomography–based cohort study.
Objective Although there are publications concerning the relationship between the vertebral artery and uncinate process, there is no practical guide detailing the dimensions of this region to use during decompression of the intervertebral foramen. The purpose of this study is to determine the anatomic parameters that can be used as a guide for thorough decompression of the intervertebral foramen.
Methods Fifty-one patients with three-dimensional computed tomography scans of the cervical spine from 2003 to 2012 were included. On axial views, we measured the distance from the midline to the medial and lateral cortices of the pedicle bilaterally from C3 to C7. On coronal reconstructed views, we measured the minimum height of the uncinate process from the cranial cortex of the pedicle adjacent to the posterior cortex of vertebral body and the maximal height of the uncinate process from the cranial cortex of the pedicle at the midportion of the vertebral body bilaterally from C3 to C7.
Results The mean distances from midline to the medial and lateral cortices of the pedicle were 10.1 ± 1.3 mm and 13.9 ± 1.5 mm, respectively. The mean minimum height of the uncinate process from the cranial cortex of the pedicle was 4.6 ± 1.6 mm and the mean maximal height was 6.1 ± 1.7 mm.
Conclusions Our results suggest that in most cases, one can thoroughly decompress the intervertebral foramen by removing the uncinate out to 13 mm laterally from the midline and 4 mm above the pedicle without violating the transverse foramen.
PMCID: PMC4577317  PMID: 26430592
cervical spine; uncinate process; transverse foramen; intervertebral foramen; decompression
3.  Distribution of ureteral stones and factors affecting their location and expulsion in patients with renal colic 
Korean Journal of Urology  2015;56(10):717-721.
To evaluate the distribution of ureteral stones and to determine their characteristics and expulsion rate based on their location.
Materials and Methods
We retrospectively reviewed computed tomography (CT) findings of 246 patients who visited our Emergency Department (ED) for renal colic caused by unilateral ureteral stones between January 2013 and April 2014. Histograms were constructed to plot the distribution of stones based on initial CT findings. Data from 144 of the 246 patients who underwent medical expulsive therapy (MET) for 2 weeks were analyzed to evaluate the factors responsible for the stone distribution and expulsion.
The upper ureter and ureterovesical junction (UVJ) were 2 peak locations at which stones initially lodged. Stones lodged at the upper ureter and ureteropelvic junction (group A) had a larger longitudinal diameter (4.21 mm vs. 3.56 mm, p=0.004) compared to those lodged at the lower ureter and UVJ (group B). The expulsion rate was 75.6% and 94.9% in groups A and B, respectively. There was no significant difference in the time interval from initiation of renal colic to arrival at the ED between groups A and B (p=0.422). Stone diameter was a significant predictor of MET failure (odds ratio [OR], 1.795; p=0.005) but the initial stone location was not (OR, 0.299; p=0.082).
The upper ureter and UVJ are 2 peak sites at which stones lodge. For stone size 10 mm or less, initial stone lodge site is not a significant predictor of MET failure in patients who have no previous history of active stone treatment in the ureter.
PMCID: PMC4610899  PMID: 26495073
Pharmaceutical adjuvants; Renal colic; Ureteral obstruction; Ureterolithiasis
4.  Highly effective peginterferon α-2a plus ribavirin combination therapy for chronic hepatitis C in hemophilia in Korea 
Clinical and Molecular Hepatology  2015;21(2):125-130.
Chronic hepatitis C (CHC) is a major comorbidity in patients with hemophilia. However, there are no published data on the efficacy of antiviral therapy in Korea. We assessed the safety and efficacy of combination therapy with peginterferon α-2a plus ribavirin for CHC in hemophilia.
Patients (n=115) were enrolled between March 2007 and December 2008. Seventy-seven patients were genotype 1 or 6, and 38 patients were genotype 2 or 3. We evaluated rapid virologic responses (RVRs), early virologic response (EVRs), end-of-treatment response (ETRs), sustained virologic response (SVRs), and relapses. Safety evaluations included adverse events and laboratory tests.
Eleven patients were excluded from the study because they had been treated previously. Among the remaining 104 treatment-naïve patients, RVR was achieved in 64 (60.6%), ETR was achieved in 95 (91.3%), and SVR was achieved in 89 (85.6%). Relapse occurred in eight patients (8.9%). Common adverse events were hair loss (56.7%) and headache (51.0%). Common hematologic adverse events were neutropenia (22.1%), anemia (27.9%), and thrombocytopenia (3.8%). However, there were no serious adverse events such as bleeding. RVR was the only predictor of SVR in multivariate analysis.
Peginterferon α-2a plus ribavirin combination treatment produced a favorable response rate in CHC patients with hemophilia without serious adverse events.
PMCID: PMC4493355  PMID: 26157749
Chronic hepatitis C; Hemophilia; Peginterferon; Ribavirin
5.  Clinical Outcomes of CyberKnife Radiotherapy in Prostate Cancer Patients: Short-term, Single-Center Experience 
Korean Journal of Urology  2014;55(3):172-177.
In this retrospective study, we analyzed the outcomes of prostate cancer patients treated with the CyberKnife radiotherapy system (Accuray).
Materials and Methods
Between 2007 and 2010, 31 patients were treated for prostate cancer by use of the CyberKnife radiotherapy system. After excluding six patients who were lost to follow-up, data for the remaining 25 patients were analyzed. Patients were divided into the CyberKnife monotherapy group and a postexternal beam radiotherapy boost group. Clinicopathologic features and treatment outcomes were compared between the groups. The primary endpoint was biochemical recurrence-free survival period based on the Phoenix definition. Toxicities were evaluated by using the Radiation Therapy Oncology Group scoring criteria.
Of 25 patients, 17 (68%) and 8 (32%) were classified in the monotherapy and boost groups, respectively. With a median follow-up of 29.3 months, most of the toxicities were grade 1 or 2 except for one patient in the boost group who experienced late grade 3 gastrointestinal toxicity. The overall biochemical recurrence rate was 20% (5/25) and the median time to biochemical recurrence was 51.9 months. None of the patients with low or intermediate risk had experienced biochemical recurrence during follow-up. Among D'Amico high-risk populations, 16.7% (1/6) in the monotherapy group and 50.0% (4/8) in the boost group experienced biochemical recurrence.
Our data support that prostate cancer treatment by use of the CyberKnife radiotherapy system is feasible. The procedure can be a viable option for managing prostate cancer either in a monotherapy setting or as a boost after conventional radiotherapy regardless of the patient's risk stratification.
PMCID: PMC3956945  PMID: 24648871
Prostate cancer; Recurrence; Stereotactic radiosurgery; Toxicity
6.  Dermatomyositis associated with hepatitis B virus-related hepatocellular carcinoma 
Dermatomyositis is an idiopathic inflammatory myopathy with typical cutaneous manifestations. It has been proposed that dermatomyositis may be caused by autoimmune responses to viral infections. Previous studies have shown an association between dermatomyositis and malignant tumors such as ovarian cancer, lung cancer, and colorectal cancer. However, a chronic hepatitis B virus (HBV) infection associated with dermatomyositis and hepatocellular carcinoma (HCC) has been very rarely reported. Here, we report a rare case of dermatomyositis coinciding with HBV-associated HCC. A 55-year-old male was confirmed to have HCC and dermatomyositis based on proximal muscle weakness, typical skin manifestations, elevated muscle enzyme levels, and muscle biopsy findings. This case suggests that HCC and/or a chronic HBV infection may be factors in the pathogenesis of dermatomyositis through a paraneoplastic mechanism.
PMCID: PMC3956994  PMID: 24648807
Dermatomyositis; Hepatitis B virus; Hepatocellular carcinoma
7.  Gene Expression Profiles of Human Adipose Tissue-Derived Mesenchymal Stem Cells Are Modified by Cell Culture Density 
PLoS ONE  2014;9(1):e83363.
Previous studies conducted cell expansion ex vivo using low initial plating densities for optimal expansion and subsequent differentiation of mesenchymal stem cells (MSCs). However, MSC populations are heterogeneous and culture conditions can affect the characteristics of MSCs. In this study, differences in gene expression profiles of adipose tissue (AT)-derived MSCs were examined after harvesting cells cultured at different densities. AT-MSCs from three different donors were plated at a density of 200 or 5,000 cells/cm2. After 7 days in culture, detailed gene expression profiles were investigated using a DNA chip microarray, and subsequently validated using a reverse transcription polymerase chain reaction (RT-PCR) analysis. Gene expression profiles were influenced primarily by the level of cell confluence at harvest. In MSCs harvested at ∼90% confluence, 177 genes were up-regulated and 102 genes down-regulated relative to cells harvested at ∼50% confluence (P<0.05, FC>2). Proliferation-related genes were highly expressed in MSCs harvested at low density, while genes that were highly expressed in MSCs harvested at high density (∼90% confluent) were linked to immunity and defense, cell communication, signal transduction and cell motility. Several cytokine, chemokine and growth factor genes involved in immunosuppression, migration, and reconstitution of damaged tissues were up-regulated in MSCs harvested at high density compared with MSCs harvested at low density. These results imply that cell density at harvest is a critical factor for modulating the specific gene-expression patterns of heterogeneous MSCs.
PMCID: PMC3882209  PMID: 24400072
8.  Important predictor of mortality in patients with end-stage liver disease 
Clinical and molecular hepatology  2013;19(2):105-115.
Prognosis is an essential part of the baseline assessment of any disease. For predicting prognosis of end-stage liver disease, many prognostic models were proposed. Child-Pugh score has been the reference for assessing the prognosis of cirrhosis for about three decades in end-stage liver disease. Despite of several limitations, recent large systematic review showed that Child-Pugh score was still robust predictors and it's components (bilirubin, albumin and prothrombin time) were followed by Child-Pugh score. Recently, Model for end-stage liver disease (MELD) score emerged as a "modern" alternative to Child-Pugh score. The MELD score has been an important role to accurately predict the severity of liver disease and effectively assess the risk of mortality. Due to several weakness of MELD score, new modified MELD scores (MELD-Na, Delta MELD) have been developed and validated. This review summarizes the current knowledge about the prognostic factors in end-stage liver disease, focusing on the role of Child-Pugh and MELD score.
PMCID: PMC3701842  PMID: 23837134
Cirrhosis; MELD score; Child score
9.  Durability of viral response after off-treatment in HBeAg positive chronic hepatitis B 
AIM: To evaluate the durability in hepatitis B e antigen (HBeAg) positive chronic hepatitis B patients who discontinued antiviral treatment.
METHODS: A total of 48 HBeAg positive chronic hepatitis B patients who were administered nucleoside analogues and maintained virological response for ≥ 6 mo [hepatitis B virus (HBV) DNA < 300 copies/mL and HBeAg seroconversion] before cessation of treatment were enrolled between February 2007 and January 2010. The criteria for the cessation of the antiviral treatment were defined as follows: (1) achievement of virological response; and (2) duration of consolidation therapy (≥ 6 mo). After treatment cessation, the patients were followed up at 3-6 mo intervals. The primary endpoint was serologic and virologic recurrence rates after withdrawal of antiviral treatment. Serologic recurrence was defined as reappearance of HBeAg positivity after HBeAg seroconversion. Virologic recurrence was defined as an increase in HBV-DNA level > 104 copies/mL after HBeAg seroconversion with previously undetectable HBV-DNA level.
RESULTS: During the median follow-up period of 18.2 mo (range: 5.1-47.5 mo) after cessation of antiviral treatment, the cumulative serological recurrence rate was 15 % at 12 mo. The median duration between the cessation of antiviral treatment and serologic recurrence was 7.2 mo (range: 1.2-10.9 mo). Of the 48 patients with HBeAg positive chronic hepatitis, 20 (41.6%) showed virological recurrence. The cumulative virologic recurrence rates at 12 mo after discontinuing the antiviral agent were 41%. The median duration between off-treatment and virologic recurrence was 7.6 mo (range: 4.3-27.1 mo). The mean age of the virological recurrence group was older than that of the non-recurrence group (46.7 ± 12.1 years vs 38.8 ± 12.7 years, respectively; P = 0.022). Age (> 40 years) and the duration of consolidation treatment (≥ 15 mo) were significant predictive factors for offtreatment durability in the multivariate analysis [P = 0.049, relative risk (RR) 0.31, 95% CI (0.096-0.998) and P = 0.005, RR 11.29, 95% CI (2.054-65.12), respectively]. Patients with age (≤ 40 years) who received consolidation treatment (≥ 15 mo) significantly showed durability in HBeAg positive chronic hepatitis B patients (P = 0.014). These results suggest that additional treatment for more than 15 mo after HBeAg seroconversion in patients who are ≤ 40 years old may be beneficial in providing a sustained virological response.
CONCLUSION: Our data suggest that HBeAg seroconversion is an imperfect end point in antiviral treatment. Long-term consolidation treatment (≥ 15 mo) in younger patients is important for producing better prognosis in HBeAg positive chronic hepatitis B.
PMCID: PMC3501777  PMID: 23180949
Durability; Seroconversion; Chronic hepatitis B; Hepatitis B e antigen positive; Recurrence; Consolidation
10.  A case of hypereosinophilic syndrome presenting with intractable gastric ulcers 
We report a rare case of hypereosinophilic syndrome (HES) presenting with intractable gastric ulcers. A 71-year-old man was admitted with epigastric pain. Initial endoscopic findings revealed multiple, active gastric ulcers in the gastric antrum. He underwent Helicobacter pylori (H pylori) eradication therapy followed by proton pump inhibitor (PPI) therapy. However, follow-up endoscopy at 4, 6, 10 and 14 mo revealed persistent multiple gastric ulcers without significant improvement. The proportion of his eosinophil count increased to 43% (total count: 7903/mm3). Abdominal-pelvic and chest computed tomography scans showed multiple small nodules in the liver and both lungs. The endoscopic biopsy specimen taken from the gastric antrum revealed prominent eosinophilic infiltration, and the liver biopsy specimen also showed eosinophilic infiltration in the portal tract and sinusoid. A bone marrow biopsy disclosed eosinophilic hyperplasia as well as increased cellularity of 70%. The patient was finally diagnosed with HES involving the stomach, liver, lung, and bone marrow. When gastric ulcers do not improve despite H pylori eradication and prolonged PPI therapy, infiltrative gastric disorders such as HES should be considered.
PMCID: PMC2797674  PMID: 20027690
Gastric ulcer; Hypereosinophilic syndrome
11.  REST Regulates Non–Cell-Autonomous Neuronal Differentiation and Maturation of Neural Progenitor Cells via Secretogranin II 
The Journal of Neuroscience  2015;35(44):14872-14884.
RE-1 silencing transcription factor (REST), a master negative regulator of neuronal differentiation, controls neurogenesis by preventing the differentiation of neural stem cells. Here we focused on the role of REST in the early steps of differentiation and maturation of adult hippocampal progenitors (AHPs). REST knockdown promoted differentiation and affected the maturation of rat AHPs. Surprisingly, REST knockdown cells enhanced the differentiation of neighboring wild-type AHPs, suggesting that REST may play a non–cell-autonomous role. Gene expression analysis identified Secretogranin II (Scg2) as the major secreted REST target responsible for the non–cell-autonomous phenotype. Loss-of-function of Scg2 inhibited differentiation in vitro, and exogenous SCG2 partially rescued this phenotype. Knockdown of REST in neural progenitors in mice led to precocious maturation into neurons at the expense of mushroom spines in vivo. In summary, we found that, in addition to its cell-autonomous function, REST regulates differentiation and maturation of AHPs non–cell-autonomously via SCG2.
SIGNIFICANCE STATEMENT Our results reveal that REST regulates differentiation and maturation of neural progenitor cells in vitro by orchestrating both cell-intrinsic and non–cell-autonomous factors and that Scg2 is a major secretory target of REST with a differentiation-enhancing activity in a paracrine manner. In vivo, REST depletion causes accelerated differentiation of newborn neurons at the expense of spine defects, suggesting a potential role for REST in the timing of the maturation of granule neurons.
PMCID: PMC4635134  PMID: 26538656
adult neurogenesis; microfludics; neurosecretory; REST/NRSF; SCG2; stem cells
12.  Comparative Analysis of Liver Injury-Associated Cytokines in Acute Hepatitis A and B 
Yonsei Medical Journal  2016;57(3):652-657.
Acute hepatitis A (AHA) and acute hepatitis B (AHB) are caused by an acute infection of the hepatitis A virus and the hepatitis B virus, respectively. In both AHA and AHB, liver injury is known to be mediated by immune cells and cytokines. In this study, we measured serum levels of various cytokines and T-cell cytotoxic proteins in patients with AHA or AHB to identify liver injury-associated cytokines.
Materials and Methods
Forty-six patients with AHA, 16 patients with AHB, and 14 healthy adults were enrolled in the study. Serum levels of 17 cytokines and T-cell cytotoxic proteins were measured by enzyme-linked immunosorbent assays or cytometric bead arrays and analyzed for correlation with serum alanine aminotransferase (ALT) levels.
Interleukin (IL)-18, IL-8, CXCL9, and CXCL10 were significantly elevated in both AHA and AHB. IL-6, IL-22, granzyme B, and soluble Fas ligand (sFasL) were elevated in AHA but not in AHB. In both AHA and AHB, the serum level of CXCL10 significantly correlated with the peak ALT level. Additionally, the serum level of granzyme B in AHA and the serum level of sFasL in AHB correlated with the peak ALT level.
We identified cytokines and T-cell cytotoxic proteins associated with liver injury in AHA and AHB. These findings deepen the existing understanding of immunological mechanisms responsible for liver injury in acute viral hepatitis.
PMCID: PMC4800355  PMID: 26996565
Hepatitis A virus; hepatitis B virus; liver injury; cytokines; chemokines
13.  An integrated systems biology approach identifies positive cofactor 4 as a factor that increases reprogramming efficiency 
Nucleic Acids Research  2016;44(3):1203-1215.
Spermatogonial stem cells (SSCs) can spontaneously dedifferentiate into embryonic stem cell (ESC)-like cells, which are designated as multipotent SSCs (mSSCs), without ectopic expression of reprogramming factors. Interestingly, SSCs express key pluripotency genes such as Oct4, Sox2, Klf4 and Myc. Therefore, molecular dissection of mSSC reprogramming may provide clues about novel endogenous reprogramming or pluripotency regulatory factors. Our comparative transcriptome analysis of mSSCs and induced pluripotent stem cells (iPSCs) suggests that they have similar pluripotency states but are reprogrammed via different transcriptional pathways. We identified 53 genes as putative pluripotency regulatory factors using an integrated systems biology approach. We demonstrated a selected candidate, Positive cofactor 4 (Pc4), can enhance the efficiency of somatic cell reprogramming by promoting and maintaining transcriptional activity of the key reprograming factors. These results suggest that Pc4 has an important role in inducing spontaneous somatic cell reprogramming via up-regulation of key pluripotency genes.
PMCID: PMC4756831  PMID: 26740582
14.  The Effectiveness of Silodosin for Nocturnal Polyuria in Elderly Men With Benign Prostatic Hyperplasia: A Multicenter Study 
To investigate improvement in nocturia and nocturnal polyuria in nocturnal polyuria patients after silodosin administration by using a 3-day frequency volume chart.
This was a prospective multicenter study. We enrolled nocturnal polyuria patients (nocturnal polyuria index [NPi]>0.33), aged ≥60 years, diagnosed with the 3-day frequency volume charts of patients with benign prostatic hyperplasia taking α-blockers. Of the 54 patients, 30 (55.6%) completed the study according to the study protocol (per-protocol group), and 24 dropped out (dropout group).
Of the 24 patients in the dropout group, 5 withdrew consent due to side effects or lack of efficacy, 7 were lost to follow-up at 4 weeks, 8 were lost to follow-up at 12 weeks, and 4 dropped out due to failure to complete 3-day frequency volume charts at 12 weeks. In the per-protocol group, there was significant improvement in the International Prostate Symptom Score (IPSS), especially question numbers 1, 3, 4, 5, 6, 7, and the quality of life question (P=0.001, P=0.007, P<0.001, P=0.003, P=0.049, P<0.001, and P<0.001, respectively). The Leeds sleep evaluation questionnaire (LSEQ) score for the sleep question improved from 64.36 to 70.43 (P=0.039). The NPi reduced from 0.4005 to 0.3573 (P=0.027); however, in many cases, there was no improvement in nocturnal polyuria itself. In intention-to-treat analysis, there were significant improvements in IPSS and LSEQ in 45 patients.
In elderly nocturnal polyuria patients, silodosin monotherapy exhibits good efficacy in improving nocturia and nocturnal polyuria; however, the mean NPi was still >0.33. Considering the high dropout rate of our study due to no implementation of 3-day frequency volume charts, prospective and large-scale studies are needed to confirm our results.
PMCID: PMC4582092  PMID: 26620902
Nocturia; Adrenergic alpha-Antagonists; Prostatic Hyperplasia
15.  Impact of MELD on Waitlist Outcome of Retransplant Candidates 
Under the current allocation system for liver transplantation (LTx), primary and retransplantation (ReTx) are treated identically. The aims of this study were (1) to compare the risk of death between ReTx and primary LTx candidates at a given MELD score and (2) to gauge the impact of the MELD-based allocation system on the waitlist outcome of ReTx candidates. Based on data of all waitlist registrants in the US between 2000 and 2006, unique adult patients with chronic liver disease were identified and followed forward to determine mortality within six months of registration. There were a total of 45,943 patients waitlisted for primary LTx and 2,081 registered for ReTx. In the MELD era (n=30,175), MELD was significantly higher among ReTx candidates than primary LTx candidates (median, 21 versus 15). Within a range of MELD scores where most transplantation took place, mortality was comparable between ReTx and primary candidates after adjusting for MELD. The probability for LTx increased significantly following implementation of the MELD-based allocation in both types of candidates. We conclude that by and large, primary and ReTx candidates fare equitably under the current MELD-based allocation system, which has contributed to a significant increase in the probability of LTx.
PMCID: PMC4547838  PMID: 21070603
16.  Clinical Factors and Viral Load Influencing Severity of Acute Hepatitis A 
PLoS ONE  2015;10(6):e0130728.
Background and Aims
Clinical manifestations of hepatitis A virus (HAV) infection vary from mild to fulminant hepatic failure (FHF) in adults. We investigated the relationship between laboratory findings, including viral load, and clinical outcomes in patients with acute hepatitis A (AHA) and evaluated predictive factors for severe acute hepatitis (s-AH).
We analyzed the clinical manifestations of AHA in 770 patients. Patients with a prothrombin time (PT) of less than 40% of normal were classified as s-AH and included 4 patients with FHF, 11 patients with acute renal failure, and 3 patients with prolonged jaundice (n = 128). Other patients were defined as mild acute hepatitis (m-AH) (n = 642). Serum samples were obtained from 48 patients with acute hepatitis A. Among them, 20 with s-AH, and 28 with m-AH, were tested for HAV RNA titer.
In a multivariate analysis, age (HR = 1.042, P = 0.041), peak creatinine (HR = 4.014, P = 0.001), bilirubin (HR = 1.153, P = 0.003), alanine aminotransferase (ALT) (HR = 1.001, P<0.001), initial lactate dehydrogenase (LDH) (HR = 1.000, P = 0.045) and total cholesterol (HR = 0.978, P<0.001) were independent factors for s-AH. Serum HAV RNA was detected in 20/20 (100%) patients with s-AH and 22/28 (78.6%) patients with m-AH. In a multivariate analysis of the 48 patients who were tested for HAV RNA, peak ALT (HR = 1.001, P = 0.004) and HAV RNA titer (HR = 2.076, P = 0.012) were independent factors for s-AH.
Clinical factors including age, peak creatinine, bilirubin, ALT, initial LDH and total cholesterol were independent factors for s-AH in a multivariate analysis. In particular, HAV load strongly correlated with the severity of hepatitis A.
PMCID: PMC4474726  PMID: 26090677
17.  A regenerative approach to the treatment of multiple sclerosis 
Nature  2013;502(7471):327-332.
Progressive phases of multiple sclerosis are associated with inhibited differentiation of the progenitor cell population that generates the mature oligodendrocytes required for remyelination and disease remission. To identify selective inducers of oligodendrocyte differentiation, we performed an image-based screen for myelin basic protein (MBP) expression using primary rat optic-nerve-derived progenitor cells. Here we show that among the most effective compounds identifed was benztropine, which significantly decreases clinical severity in the experimental autoimmune encephalomyelitis (EAE) model of relapsing-remitting multiple sclerosis when administered alone or in combination with approved immunosuppressive treatments for multiple sclerosis. Evidence from a cuprizone-induced model of demyelination, in vitro and in vivo T-cell assays and EAE adoptive transfer experiments indicated that the observed efficacy of this drug results directly from an enhancement of remyelination rather than immune suppression. Pharmacological studies indicate that benztropine functions by a mechanism that involves direct antagonism of M1 and/or M3 muscarinic receptors. These studies should facilitate the development of effective new therapies for the treatment of multiple sclerosis that complement established immunosuppressive approaches.
PMCID: PMC4431622  PMID: 24107995
18.  Phenotypic differences in hiPSC NPCs derived from patients with schizophrenia 
Molecular psychiatry  2014;20(3):361-368.
Consistent with recent reports indicating that neurons differentiated in vitro from human induced pluripotent stem cells (hiPSCs) are immature relative to those in the human brain (1, 2), gene expression comparisons of our hiPSC-derived neurons to the Allen BrainSpan Atlas indicate that they most resemble fetal brain tissue. This finding suggests that, rather than modeling the late features of schizophrenia (SZ), hiPSC-based models may be better suited for the study of disease predisposition. We now report that a significant fraction of the gene signature of SZ hiPSC-derived neurons is conserved in SZ hiPSC neural progenitor cells (NPCs). We used two, independent discovery-based approaches - microarray gene expression and stable isotope labeling by amino acids in cell culture (SILAC) quantitative proteomic mass spectrometry analyses – to identify cellular phenotypes in SZ hiPSC NPCs from four SZ patients. From our findings that SZ hiPSC NPCs show abnormal gene expression and protein levels related to cytoskeletal remodeling and oxidative stress, we predicted, and subsequently observed, aberrant migration and increased oxidative stress in SZ hiPSC NPCs. This approach, consisting of reproducible phenotypes identified through scalable assays, can be applied to expanded cohorts of SZ patients, making it a potentially valuable tool with which to study the developmental mechanisms contributing to SZ.
PMCID: PMC4182344  PMID: 24686136
Schizophrenia; induced pluripotent stem cells; neural progenitor cells; migration; oxidative stress
19.  Long-term outcomes of two rescue therapies in lamivudine-refractory patients with chronic hepatitis B: combined lamivudine and adefovir, and 1-mg entecavir 
Clinical and Molecular Hepatology  2014;20(3):267-273.
Adefovir (ADV) and lamivudine (LAM) combination therapy (ADV+LAM) has been a useful option for patients with LAM-resistant (LAM-r) chronic hepatitis B (CHB). However, the long-term outcomes of LAM+ADV and 1-mg entecavir (ETV) rescue therapies have still been limited. The aim of this study was to determine the long-term outcomes of these two rescue therapies.
Sixty patients with LAM-r CHB underwent rescue therapy with LAM+ADV (n=36) or 1-mg ETV (n=24). We determined the duration of rescue therapy, timing and type of mutation, undetectable serum hepatitis B virus (HBV) DNA by PCR (lower limitation of detection, < 140 copies/mL), biochemical response (alanine aminotransferase < 40 IU/mL), and the incidence of hepatitis B virus e antigen (HBeAg) seroconversion and virologic breakthrough.
Baseline characteristics did not differ between the two therapy groups. The duration of rescue therapy was 56 months (range, 14-100 months) in the ADV+LAM group and 42 months (range, 12-73 months) in the ETV group (P=0.036). The cumulative rates of HBV DNA undetectability and HBeAg seroconversion up to 6 years were 88.6% and 43.0%, respectively, in the ADV+LAM group, and 45.8% and 31.8% in the ETV group. The rate of virologic breakthrough and resistance was 14.4% in the ADV+LAM group and 71.9% in the ETV group (P=0.001).
Combination of LAM and ADV therapy for up to 6 years achieved modest rates of virological suppression and resistance. ETV is not an optimal therapy because the risk of viral breakthrough to ETV increases over time.
PMCID: PMC4197175  PMID: 25320730
Chronic hepatitis B; Lamivudine; Adefovir; Entecavir; Resistance
20.  Spermatogonial stem cell enrichment using simple grafting of testis and in vitro cultivation 
Scientific Reports  2014;4:5923.
Enrichment of spermatogonial stem cells (SSCs) from the mammalian adult testis faces several limitations owing to their relatively low numbers among many types of advanced germ cells and somatic cells. The aim of the present study was to improve the isolation efficiency of SSCs using a simple tissue grafting method to eliminate the existing advanced germ cells. Sliced testis parenchyma obtained from adult ICR or EGFP-expressing transgenic mice were grafted heterotropically under the dorsal skin of nude mice. The most advanced germ cells disappeared in the grafted tissues after 2–4 weeks. Grafted tissues were dissociated enzymatically and plated in culture dishes. During in vitro culture, significantly more SSCs were obtained from the grafted testes than from non-grafted controls, and the isolated SSCs had proliferative potential and were successfully maintained. Additionally, EGFP-expressing SSCs derived from graft parenchyma were transplanted into bulsufan-treated recipient mice testes. Finally, we obtained EGFP-expressing pups after in vitro fertilization using spermatozoa derived from transplanted SSCs. These results suggest that subcutaneous grafting of testis parenchyma and the subsequent culture methods provide a simple and efficient isolation method to enrich for SSCs in adult testis without specific cell sorting methods and may be useful tools for clinical applications.
PMCID: PMC4118148  PMID: 25080919
21.  Monitoring the Differentiation and Migration Patterns of Neural Cells Derived from Human Embryonic Stem Cells Using a Microfluidic Culture System 
Molecules and Cells  2014;37(6):497-502.
Microfluidics can provide unique experimental tools to visualize the development of neural structures within a microscale device, which is followed by guidance of neurite growth in the axonal isolation compartment. We utilized microfluidics technology to monitor the differentiation and migration of neural cells derived from human embryonic stem cells (hESCs). We co-cultured hESCs with PA6 stromal cells, and isolated neural rosette-like structures, which subsequently formed neurospheres in suspension culture. Tuj1-positive neural cells, but not nestin-positive neural precursor cells (NPCs), were able to enter the microfluidics grooves (microchannels), suggesting that neural cell-migratory capacity was dependent upon neuronal differentiation stage. We also showed that bundles of axons formed and extended into the microchannels. Taken together, these results demonstrated that microfluidics technology can provide useful tools to study neurite outgrowth and axon guidance of neural cells, which are derived from human embryonic stem cells.
PMCID: PMC4086344  PMID: 24938227
axons; human embryonic stem cells; microfluidics; migration; neural differentiation
22.  The Impacts of C-Reactive Protein and Atrial Fibrillation on Carotid Atherosclerosis and Ischemic Stroke in Patients with Suspected Ischemic Cerebrovascular Disease: A Single-Center Retrospective Observational Cohort Study 
Korean Circulation Journal  2013;43(12):796-803.
Background and Objectives
Carotid intima-media thickness (IMT) is associated with chronic inflammation, and C-reactive protein (CRP) level is elevated in patients with atrial fibrillation (AF). We investigated the impacts of CRP and AF on carotid atherosclerosis and ischemic stroke in patients with suspected ischemic cerebrovascular disease.
Subjects and Methods
One-hundred forty patients (78 males) with suspected ischemic cerebrovascular disease underwent carotid ultrasonography. The mean common carotid artery IMT, mean internal carotid artery (ICA) IMT, and plaque score were measured. Patients were divided into four groups according to the presence of AF and elevated CRP level {n=46 for AF(-)CRP(-), n=38 for AF(-)CRP(+), n=43 for AF(+)CRP(-), and n=13 for AF(+)CRP(+)}.
Common carotid artery IMT was significantly higher in the AF(-)CRP(+) (0.98±0.51 mm) and AF(+)CRP(+) (0.96±0.27 mm) groups compared to the AF(-)CRP(-) (0.80±0.32 mm) and AF(+)CRP(-) (0.77±0.19 mm) groups (p=0.027). Although there was no significant difference in mean ICA IMT among the groups, plaque score was the highest in the AF(+)CRP(+) (4.18±3.84 mm) group, followed by AF(-)CRP(+) (3.87±2.78 mm), AF(+)CRP(-) (1.34±2.61 mm), and AF(-)CRP(-) (1.17±2.02 mm) (p<0.001). The AF(+)CRP(+) group showed significantly higher incidence of ischemic stroke than the other groups (all p<0.05). Binary logistic regression analysis showed that age {odds ratio (OR)=1.033, p=0.001}, elevated CRP (OR=3.884, p=0.001), and the presence of AF (OR=1.375, p=0.018) were significantly correlated with incidence of ischemic stroke.
Elevated plasma CRP concentration may be a reliable surrogate marker for predicting carotid atherosclerosis in patients with AF, which may be related to increased risk of ischemic stroke.
PMCID: PMC3875695  PMID: 24385990
Atrial fibrillation; C-reactive protein; Carotid atherosclerosis
23.  An Unusual Case of Superior Vena Cava Syndrome Caused by the Intravascular Invasion of an Invasive Thymoma 
Superior vena cava syndrome (SVCS) is usually caused by extrinsic compression or invasion of the superior vena cava (SVC) by malignant tumors involving mediastinal structures. Although thymomas are well-known causes of SVCS, cases of SVCS caused by malignant thymomas protruding into adjacent vessels draining the SVC with thrombosis have been very rarely reported worldwide. We experienced a 39-year-old female patient with SVCS that developed after the direct invasion of the left brachiocephalic vein (LBCV) and SVC by an anterior mediastinal mass with a high maximum standardized uptake value on the chest computed tomography (CT) and positron emission tomography-CT. Based on these results, she underwent en bloc resection of the tumor, including removal of the involved vessels, and was eventually diagnosed as having a type B2 thymoma permeating into the LBCV and SVC. We present this case as a very rare form of SVCS caused by an invasive thymoma.
PMCID: PMC3861377  PMID: 24348669
Thymoma; Superior Vena Cava Syndrome; Positron-Emission Tomography
24.  Plasma membrane calcium ATPase regulates bone mass by fine-tuning osteoclast differentiation and survival 
The Journal of Cell Biology  2012;199(7):1145-1158.
Plasma membrane calcium ATPases PMCA1 and PMCA4 regulate osteoclast differentiation and survival by regulating NFATc1 and NO.
The precise regulation of Ca2+ dynamics is crucial for proper differentiation and function of osteoclasts. Here we show the involvement of plasma membrane Ca2+ ATPase (PMCA) isoforms 1 and 4 in osteoclastogenesis. In immature/undifferentiated cells, PMCAs inhibited receptor activator of NF-κB ligand–induced Ca2+ oscillations and osteoclast differentiation in vitro. Interestingly, nuclear factor of activated T cell c1 (NFATc1) directly stimulated PMCA transcription, whereas the PMCA-mediated Ca2+ efflux prevented NFATc1 activation, forming a negative regulatory loop. PMCA4 also had an anti-osteoclastogenic effect by reducing NO, which facilitates preosteoclast fusion. In addition to their role in immature cells, increased expression of PMCAs in mature osteoclasts prevented osteoclast apoptosis both in vitro and in vivo. Mice heterozygous for PMCA1 or null for PMCA4 showed an osteopenic phenotype with more osteoclasts on bone surface. Furthermore, PMCA4 expression levels correlated with peak bone mass in premenopausal women. Thus, our results suggest that PMCAs play important roles for the regulation of bone homeostasis in both mice and humans by modulating Ca2+ signaling in osteoclasts.
PMCID: PMC3529522  PMID: 23266958
25.  Quantitative Analysis of Axonal Transport by Using Compartmentalized and Surface Micropatterned Culture of Neurons 
ACS Chemical Neuroscience  2012;3(6):433-438.
Mitochondria, synaptic vesicles, and other cytoplasmic constituents have to travel long distance along the axons from cell bodies to nerve terminals. Interruption of this axonal transport may contribute to many neurodegenerative diseases including Alzheimer’s disease (AD). It has been recently shown that exposure of cultured neurons to β-amyloid (Aβ) resulted in severe impairment of mitochondrial transport. This Letter describes an integrated microfluidic platform that establishes surface patterned and compartmentalized culture of neurons for studying the effect of Aβ on mitochondria trafficking in full length of axons. We have successfully quantified the trafficking of fluorescently labeled mitochondria in distal and proximal axons using image processing. Selective treatment of Aβ in the somal or axonal compartments resulted in considerable decrease in mitochondria movement in a location dependent manner such that mitochondria trafficking slowed down more significantly proximal to the location of Aβ exposure. Furthermore, this result suggests a promising application of microfluidic technology for investigating the dysfunction of axonal transport related to neurodegenerative diseases.
PMCID: PMC3643179  PMID: 24358503
β-Amyloid; axonal transport; mitochondrial trafficking; microfludics; surface micropatterning; image processing

Results 1-25 (42)