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1.  Notch-Regulated Oligodendrocyte Specification From Radial Glia in the Spinal Cord of Zebrafish Embryos 
During vertebrate neural development, many dividing neuroepithelial precursors adopt features of radial glia, which are now known to also serve as neural precursors. In mammals, most radial glia do not persist past early postnatal stages, whereas zebrafish maintain large numbers of radial glia into adulthood. The mechanisms that maintain and specify radial glia for different fates are still poorly understood. We investigated formation of radial glia in the spinal cord of zebrafish and the role of Notch signaling in their maintenance and specification. We found that spinal cord precursors begin to express gfap+, a marker of radial glia, during neurogenesis and that gfap cells give rise to both neurons and oligodendrocytes. We also determined that Notch signaling is continuously required during embryogenesis to maintain radial glia, limit motor neuron formation and permit oligodendrocyte development, but that radial glia seem to be refractory to changes in Notch activity in postembryonic animals.
PMCID: PMC2646814  PMID: 18627107
spinal cord; oligodendrocyte; motor neuron; radial glia; zebrafish transgenic; Notch
2.  Skeletal muscle dysfunction in patients with chronic obstructive pulmonary disease 
Chronic obstructive pulmonary disease (COPD) is a debilitating disease characterized by inflammation-induced airflow limitation and parenchymal destruction. In addition to pulmonary manifestations, patients with COPD develop systemic problems, including skeletal muscle and other organ-specific dysfunctions, nutritional abnormalities, weight loss, and adverse psychological responses. Patients with COPD often complain of dyspnea on exertion, reduced exercise capacity, and develop a progressive decline in lung function with increasing age. These symptoms have been attributed to increases in the work of breathing and in impairments in gas exchange that result from airflow limitation and dynamic hyperinflation. However, there is mounting evidence to suggest that skeletal muscle dysfunction, independent of lung function, contributes significantly to reduced exercise capacity and poor quality of life in these patients. Limb and ventilatory skeletal muscle dysfunction in COPD patients has been attributed to a myriad of factors, including the presence of low grade systemic inflammatory processes, nutritional depletion, corticosteroid medications, chronic inactivity, age, hypoxemia, smoking, oxidative and nitrosative stresses, protein degradation and changes in vascular density. This review briefly summarizes the contribution of these factors to overall skeletal muscle dysfunction in patients with COPD, with particular attention paid to the latest advances in the field.
PMCID: PMC2650609  PMID: 19281080
skeletal muscles; chronic obstructive pulmonary disease; diaphragm; quadriceps; fatigue; disuse; atrophy; smoking; exercise
3.  Gastric Schwannoma 
Yonsei Medical Journal  2008;49(6):1052-1054.
Schwannomas, also known as neurinomas or neurilemmomas, are generally benign, slow-growing neoplasms originating in any nerve that has a Schwann cell sheath. These neoplasms are rare among the spindle cell mesenchymal tumors of the gastrointestinal tract, but develop most commonly in the stomach representing 0.2% of all gastric tumors. We present the case of a 57-year-old female patient with a large schwannoma in the stomach that was palpable in the abdomen. She underwent subtotal gastrectomy under suspicion of gastrointestinal stromal tumor (GIST), but post-operative histopathological and immunohistochemical findings showed a fascicular arrangement of spindle cell with pallisading nuclei, and positive for S-100 protein with negative smooth muscle actin (SMA). These results confirmed schwannoma as the diagnosis.
PMCID: PMC2628015  PMID: 19108033
Schwannoma; stomach; submucosal tumor; S-100 protein
4.  CD36 signaling inhibits the translation of heat shock protein 70 induced by oxidized low density lipoprotein through activation of peroxisome proliferators-activated receptor γ 
Experimental & Molecular Medicine  2008;40(6):658-668.
Oxidized LDL (OxLDL), a causal factor in atherosclerosis, induces the expression of heat shock proteins (Hsp) in a variety of cells. In this study, we investigated the role of CD36, an OxLDL receptor, and peroxisome proliferator-activated receptor γ (PPARγ) in OxLDL-induced Hsp70 expression. Overexpression of dominant-negative forms of CD36 or knockdown of CD36 by siRNA transfection increased OxLDL-induced Hsp70 protein expression in human monocytic U937 cells, suggesting that CD36 signaling inhibits Hsp70 expression. Similar results were obtained by the inhibition of PPARγ activity or knockdown of PPARγ expression. In contrast, overexpression of CD36, which is induced by treatment of MCF-7 cells with troglitazone, decreased Hsp70 protein expression induced by OxLDL. Interestingly, activation of PPARγ through a synthetic ligand, ciglitazone or troglitazone, decreased the expression levels of Hsp70 protein in OxLDL-treated U937 cells. However, major changes in Hsp70 mRNA levels were not observed. Cycloheximide studies demonstrate that troglitazone attenuates Hsp70 translation but not Hsp70 protein stability. PPARγ siRNA transfection reversed the inhibitory effects of troglitazone on Hsp70 translation. These results suggest that CD36 signaling may inhibit stress-induced gene expression by suppressing translation via activation of PPARγ in monocytes. These findings reveal a new molecular basis for the anti-inflammatory effects of PPARγ.
PMCID: PMC2679336  PMID: 19116451
antigens, CD36; HSP70 heat-shock proteins; oxidized low density lipoprotein; PPARγ; protein biosynthesis
5.  Plant growth promotion and Penicillium citrinum 
BMC Microbiology  2008;8:231.
Endophytic fungi are known plant symbionts. They produce a variety of beneficial metabolites for plant growth and survival, as well as defend their hosts from attack of certain pathogens. Coastal dunes are nutrient deficient and offer harsh, saline environment for the existing flora and fauna. Endophytic fungi may play an important role in plant survival by enhancing nutrient uptake and producing growth-promoting metabolites such as gibberellins and auxins. We screened roots of Ixeris repenes (L.) A. Gray, a common dune plant, for the isolation of gibberellin secreting endophytic fungi.
We isolated 15 endophytic fungi from the roots of Ixeris repenes and screened them for growth promoting secondary metabolites. The fungal isolate IR-3-3 gave maximum plant growth when applied to waito-c rice and Atriplex gemelinii seedlings. Analysis of the culture filtrate of IR-3-3 showed the presence of physiologically active gibberellins, GA1, GA3, GA4 and GA7 (1.95 ng/ml, 3.83 ng/ml, 6.03 ng/ml and 2.35 ng/ml, respectively) along with other physiologically inactive GA5, GA9, GA12, GA15, GA19, GA20 and, GA24. The plant growth promotion and gibberellin producing capacity of IR-3-3 was much higher than the wild type Gibberella fujikuroi, which was taken as control during present study. GA5, a precursor of bioactive GA3 was reported for the first time in fungi. The fungal isolate IR-3-3 was identified as a new strain of Penicillium citrinum (named as P. citrinum KACC43900) through phylogenetic analysis of 18S rDNA sequence.
Isolation of new strain of Penicillium citrinum from the sand dune flora is interesting as information on the presence of Pencillium species in coastal sand dunes is limited. The plant growth promoting ability of this fungal strain may help in conservation and revegetation of the rapidly eroding sand dune flora. Penicillium citrinum is already known for producing mycotoxin citrinin and cellulose digesting enzymes like cellulase and endoglucanase, as well as xylulase. Gibberellins producing ability of this fungus and the discovery about the presence of GA5 will open new aspects of research and investigations.
PMCID: PMC2631606  PMID: 19099608
6.  The effect of adjuvant hormonal therapy on the endometrium and ovary of breast cancer patients 
Journal of Gynecologic Oncology  2008;19(4):256-260.
To investigate the effect of adjuvant hormonal therapy on the endometrium and ovary of breast cancer patients.
A retrospective review was performed on the 207 patients who had taken tamoxifen or anastrozole, as adjuvant hormonal therapy after breast cancer surgery between January 2003 and December 2006. Gynecologic surveillance constituted of ultrasonographic exam of the endometrial thickness and ovarian cyst formation. The patients were classified into three groups and analyzed; premenopausal/postmenopausal women receiving tamoxifen and women receiving anastrozole.
Mean duration of follow up was 20.6±6.6 months. There was no difference of mean endometrial thickness before hormonal therapy among the three groups (p=0.327). In women receiving tamoxifen, the endometrium was continuously thickened in proportion to the duration of the therapy irrespective of menopausal status while it remained unchanged in women receiving anastrozole (p<0.05). Endometrial biopsies were performed in 28 patients receiving tamoxifen. The most common histologic finding was proliferative endometrium in premenopausal women (7/21) and atrophic endometrium in postmenopausal women (6/7). There was no case of endometrial cancer in both groups. Ovarian cyst was found in 32 women and the most were developed in premenopausal women receiving tamoxifen (30/32). All of them showed benign nature on transvaginal ultrasonographic findings.
Women undergoing adjuvant hormonal therapy after breast cancer surgery exhibited changes in the endometrium and ovary. However most changes were not a serious problem in this study and frequent gynecologic surveillance in these patients needs further investigation.
PMCID: PMC2676481  PMID: 19471651
Breast cancer; Tamoxifen; Anastrozole; Endometrium
7.  Clinical Factors Associated with Brachial-Ankle Pulse Wave Velocity in Patients on Maintenance Hemodialysis 
Pulse wave velocity (PWV) is a main parameter for arterial stiffness. In patients with end-stage renal disease (ESRD), PWV is known to be associated with increased mortality. But factors related to the increased PWV in ESRD patients are not well defined. In addition, the carotid-femoral PWV (cfPWV) measurement, which traditionally has been used to evaluate arterial stiffness, has low reproducibility. Recently, brachial-ankle PWV (baPWV) measurement, which can be performed more easily than cfPWV measurement, has become available as a means of measuring PWV. The aim of this study is to investigate the clinical factors associated with increased baPWV in ESRD patients. BaPWV was examined for 65 ESRD patients on maintenance hemodialysis during the period between the 7th to the 11th of February in 2005 using VP-1000. The clinical factors included age, sex, smoking history, blood pressure, diabetes, body mass index, interdialytic weight gain, duration of dialysis, lipid profile, uric acid, albumin, creatinine, C-reactive protein, calcium, phosphate, intact parathyroid hormone, and hematocrit were analyzed regarding associations (or to determine associations) with baPWV. The median age was 53.8±12.0, 31 males and 34 females. BaPWV was 18.9±5.2 m/s and there was no significant difference between gender (18.1±4.4 m/s vs 19.4±5.9 m/s, p=NS). In multiple regression models, age, predialysis systolic blood pressure, and diabetes were independent variables. In conclusion, age, systolic blood pressure, and diabetes were correlated with baPWV in ESRD patients. Thus baPWV measured by simple, noninvasive methods may become available for screening high risk groups in ESRD patients, although further longitudinal studies are necessary.
PMCID: PMC3894478  PMID: 24459524
atherosclerosis; renal dialysis; blood pressure
8.  gp96 Is a Human Colonocyte Plasma Membrane Binding Protein for Clostridium difficile Toxin A▿  
Infection and Immunity  2008;76(7):2862-2871.
Clostridium difficile toxin A (TxA), a key mediator of antibiotic-associated colitis, requires binding to a cell surface receptor prior to internalization. Our aim was to identify novel plasma membrane TxA binding proteins on human colonocytes. TxA was coupled with biotin and cross-linked to the surface of HT29 human colonic epithelial cells. The main colonocyte binding protein for TxA was identified as glycoprotein 96 (gp96) by coimmunoprecipitation and mass spectrum analysis. gp96 is a member of the heat shock protein family, which is expressed on human colonocyte apical membranes as well as in the cytoplasm. TxA binding to gp96 was confirmed by fluorescence immunostaining and in vitro coimmunoprecipitation. Following TxA binding, the TxA-gp96 complex was translocated from the cell membrane to the cytoplasm. Pretreatment with gp96 antibody decreased TxA binding to colonocytes and inhibited TxA-induced cell rounding. Small interfering RNA directed against gp96 reduced gp96 expression and cytotoxicity in colonocytes. TxA-induced inflammatory signaling via p38 and apoptosis as measured by activation of BAK (Bcl-2 homologous antagonist/killer) and DNA fragmentation were decreased in gp96-deficient B cells. We conclude that human colonocyte gp96 serves as a plasma membrane binding protein that enhances cellular entry of TxA, participates in cellular signaling events in the inflammatory cascade, and facilitates cytotoxicity.
PMCID: PMC2446715  PMID: 18411291
9.  A Study of the Reliability and Validity of the Korean Version of the Penn Alcohol Craving Scale for Alcohol-Dependent Patients 
Psychiatry Investigation  2008;5(3):175-178.
The Penn Alcohol Craving Scale (PACS) is a stronger predictor of subsequent drinking and relapse of alcohol dependence that can be administered more quickly and easily than other craving scales. The goal of this study was to develop the Korean version of the Penn Alcohol Craving Scale (PACS-K).
To examine the psychometric properties of the PACS-K, responses were chosen from 80 patients admitted to a treatment facility for alcohol dependence.
The PACS-K possesses good psychometric properties, as assessed by Cronbach's α estimates (Cronbach's α=0.91). The test-retest reliability of the PACS-K showed high correlation (p<0.01) when the retest interval was 1 day. When the validity of the PACS-K was investigated using correlation analysis with two other craving scales (the Obsessive Compulsive Drinking Scale (OCDS) and the Visual Analogue Scale (VAS), high correlations were obtained between total PACS scores and total OCDS scores, and between total PACS scores and VAS scores (p<0.01, respectively).
The PACS-K is a reliable and valid measure of alcohol cravings, and it could be useful for predicting which individuals are at risk for subsequent relapse.
PMCID: PMC2796029  PMID: 20046362
Korean version of the Penn Alcohol Craving Scale; Reliability; Validity; Alcohol
10.  Endobronchial Tuberculosis Presenting as Right Middle Lobe Syndrome: Clinical Characteristics and Bronchoscopic Findings in 22 Cases 
Yonsei Medical Journal  2008;49(4):615-619.
Endobronchial tuberculosis (EBTB) presenting as right middle lobe syndrome (RMLS) is an uncommon clinical condition. We investigated the clinical characteristics in patients with EBTB presenting as RMLS.
Patients and Methods
We retrospectively reviewed the records of 22 patients with EBTB presenting as RMLS who were diagnosed at our hospital from 2003 to 2006.
Its occurrence was more common in females than males (F, 18; M, 4). The mean age was 70.3 ± 8.5 years, and 17 patients were above the age of 65 years. Cough with sputum was the most common manifestation and 2 patients were asymptomatic. In bronchoscopic analysis, the most common finding was edematous-type EBTB, which was found in 15 patients, followed by actively caseating type in 6 and tumorous type in 1. Acid-fast bacilli (AFB) staining for bronchial washing fluid was positive in only 5 patients: 1 with edematous type and 4 with actively caseating type. Bronchoscopic biopsy showed chronic granulomatous inflammation in 16 patients. Follow-up chest X-ray after treatment showed complete disappearance of the lesion in 2 patients, more than 50% improvement in 5, less than 50% improvement in 5, and no change of lesion in 4.
Edematous-type EBTB was the most common type of EBTB presenting as RMLS, and it usually occurred in elderly patients. Culturing for mycobacterium and histologic examination by bronchoscopy are necessary for proper diagnosis in these patients.
PMCID: PMC2615288  PMID: 18729304
Endobronchial tuberculosis; right middle lobe syndrome
11.  Leiomyosarcoma of the Ovarian Vein: a Case Report with Radiological Findings 
Korean Journal of Radiology  2008;9(Suppl):S14-S17.
Leiomyosarcomas of the ovarian vein are very rare. Four cases have been reported in the English language clinical literature. We present a case of leiomyosarcomas where the use of multi-detector CT had a substantial role in the establishment of the preoperative diagnosis. The radiological images as well as intraoperative features are illustrated. We also discuss the radiological findings of the ovarian vein leiomyosarcoma in comparison with those of other venous or retroperitoneal leiomyosarcomas. We expect that the use of multi-detector CT will be the choice for the diagnostic work-up of vascular leiomyosarcomas.
PMCID: PMC2627197  PMID: 18607118
Leiomyosarcoma; Retroperitoneal space, neoplasms; Veins, ovarian; Veins, CT; Veins, US
12.  A "Benign" Sphenoid Ridge Meningioma Manifesting as a Subarachnoid Hemorrhage Associated with Tumor Invasion into the Middle Cerebral Artery 
Korean Journal of Radiology  2008;9(Suppl):S10-S13.
Meningioma rarely manifests as a subarachnoid hemorrhage (SAH), and invasion directly into a major intracranial artery is extremely rare. To the best of our knowledge, meningioma presenting with an SAH associated with major intracranial arterial invasion has never been reported. We present a case of sphenoid ridge meningotheliomatous meningioma manifesting as an SAH without pathologically atypical or malignant features, due to direct tumor invasion into the middle cerebral artery.
PMCID: PMC2627185  PMID: 18607117
Brain, hemorrhage; Brain neoplasms; Arteries, middle cerebral
13.  The first generation of a BAC-based physical map of Brassica rapa 
BMC Genomics  2008;9:280.
The genus Brassica includes the most extensively cultivated vegetable crops worldwide. Investigation of the Brassica genome presents excellent challenges to study plant genome evolution and divergence of gene function associated with polyploidy and genome hybridization. A physical map of the B. rapa genome is a fundamental tool for analysis of Brassica "A" genome structure. Integration of a physical map with an existing genetic map by linking genetic markers and BAC clones in the sequencing pipeline provides a crucial resource for the ongoing genome sequencing effort and assembly of whole genome sequences.
A genome-wide physical map of the B. rapa genome was constructed by the capillary electrophoresis-based fingerprinting of 67,468 Bacterial Artificial Chromosome (BAC) clones using the five restriction enzyme SNaPshot technique. The clones were assembled into contigs by means of FPC v8.5.3. After contig validation and manual editing, the resulting contig assembly consists of 1,428 contigs and is estimated to span 717 Mb in physical length. This map provides 242 anchored contigs on 10 linkage groups to be served as seed points from which to continue bidirectional chromosome extension for genome sequencing.
The map reported here is the first physical map for Brassica "A" genome based on the High Information Content Fingerprinting (HICF) technique. This physical map will serve as a fundamental genomic resource for accelerating genome sequencing, assembly of BAC sequences, and comparative genomics between Brassica genomes. The current build of the B. rapa physical map is available at the B. rapa Genome Project website for the user community.
PMCID: PMC2432078  PMID: 18549474
14.  Dynamic left ventricular outflow tract obstruction without basal septal hypertrophy, caused by catecholamine therapy and volume depletion 
Hypertrophic cardiomyopathy (HCM) with hypertrophy of the basal septum is the most common etiology of left ventricular outflow tract (LVOT) obstruction.
In this article, we report the case of a patient with a structurally normal heart who developed hemodynamic deterioration due to severe LVOT obstruction following treatment with catecholamines. Hypovolemia accompanied with a hyperdynamic condition, resulting from catecholamine treatment, may cause dynamic LVOT obstruction due to the systolic anterior motion of the mitral valve leaflet. The solution for this is early recognition and correction of aggravating factors such as, withdrawal of catecholamine therapy and volume replacement.
PMCID: PMC2686978  PMID: 18646515
Left ventricular outflow obstruction; Catecholamines
15.  Evaluation of fat sources (lecithin, mono-glyceride and mono-diglyceride) in weaned pigs: Apparent total tract and ileal nutrient digestibilities 
Nutrition Research and Practice  2008;2(2):130-133.
This study was conducted to investigate the effects of lecithin, mono-glyceride and mono-diglyceride on apparent total tract and ileal nutrient digestibilities in nursery pigs. Twenty [(Landrace × Yorkshire) × Duroc] barrows were surgically fitted with simple T-cannulas. Dietary treatments included 1) CON (basal diet: soy oil), 2) LO (lecithin 0.5%), 3) MO (mono-glyceride 0.5%), 4) MG (mono-glyceride 1.0%) and 5) MDG (mono-diglyceride 1.0%). In apparent total tract nutrient digestibility, dry matter (DM) and gross energy (GE) digestibilities of MDG treatments were higher than LO and MG treatments (p<0.05). In nitrogen (N) digestibility, LO treatment showed the lowest compared to others (p<0.05). The digestibility of crude fat was higher in MDG treatment than CON and LO treatments (p<0.05). In apparent ileal nutrient digestibility, DM digestibility was higher in MDG treatment than LO and MG treatments (p<0.05). GE digestibility was higher in MDG treatment than LO, MO and MG treatments (p<0.05). N digestibility of MDG treatment was greater than LO treatment (p<0.05). Also, the digestibility of crude fat was higher in MDG treatment than CON and LO treatments (p<0.05). In conclusion, mono-diglyceride can increase apparent total tract nutrient and apparent ileal nutrient digestibilities of DM, GE, N and crude fat.
PMCID: PMC2815320  PMID: 20126377
Lecithin; monoglyceride; ileal digestibility; weanling pigs
16.  Risk Factors Associated with the Halo Phenomenon after Lumbar Fusion Surgery and its Clinical Significance 
Asian Spine Journal  2008;2(1):22-26.
Study Design
Retrospective study.
First, to examine the association between bone mineral density (BMD) and the halo phenomenon, and second, to investigate risk factors predisposing to the halo phenomenon and its correlation with clinical outcomes.
Overview of Literature
The few in vivo studies regarding the relationship between pedicle screw stability and BMD have shown conflicting results.
Forty-four female patients who underwent spine fusion surgery due to spinal stenosis were included in this study. The halo phenomenon and fusion state were evaluated through plain radiographs performed immediately after surgery and through the final outpatient follow-up examination. BMD, osteoarthritis grade in the hip and knee joints, and surgical outcome were also evaluated.
BMD was not related to the halo phenomenon, but age, absence of osteoarthritis in the knee, and non-union state were found to be significant risk factors for the halo phenomenon. However, the radiological halo phenomenon did not correlate with clinical outcome (visual analogue scale for back pain and leg pain).
The halo phenomenon is a simple phenomenon that can develop during follow-up after pedicle screw fixation. It does not influence clinical outcomes, and thus it is thought that hydroxyapatite coating screws, expandable screws, cement augmentation, and additional surgeries are not required, if their purpose is to prevent the halo phenomenon.
PMCID: PMC2857487  PMID: 20411138
Halo phenomenon; Pedicle screw; Bone mineral density
17.  Recurrent Symptomatic Hyperglycemia on Maintenance Hemodialysis is not Necessarily Related to Hypertonicity : A Case Report 
On view of the absent or minimal osmotic diuresis in end stage renal disease, hyperglycemia on maintenance hemolysis as compared to nonketotic hyperosmolar status without underlying advanced renal failure has been noted to show a wide clinical spectrum form severe manifestations by hypertonicity to no clinical manifestations at all. We experienced a 60-year-old man with a known history of type 2 diabetes mellitus on maintenance hemodialysis for 2 years, who was admitted 4 times within 1 year with hyperglycemia (>500 mg/dL) accompanied by recurrent nausea and vomiting at each admission. However, the calculated effective osmolality (tonicity) in this case ranged only from 286 to 303 mOsm/kg H2O. During the past 6 months following meticulous education for the importance of compliance to medication, especially prokinetics for diabetic gastroparesis, he developed no further episode of hyperglycemia or nausea and vomiting.
PMCID: PMC3894489  PMID: 24459523
hyperglycemia; hemodialysis; hyperosmolality
18.  Hepatic cyst misdiagnosed as a gastric submucosal tumor: A case report 
We describe here a case of 51-year-old woman with a symptomatic hepatic cyst that was misdiagnosed as a gastric submucosal tumor (SMT) with endoscopic ultrasound (EUS) and CT scan. The patient presented with an epigastric pain for two months. On endoscopy, a submucosal tumor was found on the cardia of the stomach. Based on EUS and abdominal CT scan, the lesion was diagnosed as a gastric duplication cyst or a gastrointestinal stromal tumor (GIST). The operative plan was laparoscopic wedge resection for the GIST of the gastric cardia. A cystic mass arising from the left lateral segment of the liver was found at the laparoscopic examination. There was no abnormal finding at the gastric cardia. She was treated by laparoscopic hepatic wedge resection including the hepatic cyst using an endoscopic linear stapler.
PMCID: PMC2712182  PMID: 18494066
Hepatic cyst; Submucosal tumor; Stomach
19.  Implication of leucyl-tRNA synthetase 1 (LARS1) over-expression in growth and migration of lung cancer cells detected by siRNA targeted knock-down analysis 
Experimental & Molecular Medicine  2008;40(2):229-236.
Molecular mechanism of lung carcinogenesis and its aggressive nature is still largely elusive. To uncover the biomarkers related with tumorigenesis and behavior of lung cancer, we screened novel differentially expressed genes (DEG) in A549 lung cancer cell line by comparison with CCD-25Lu, normal pulmonary epithelial cell line, using annealing control primer(ACP)-based GeneFishing system. Of the DEGs, over-expression of leucyl-tRNA synthetase 1 (LARS1) was prominent and this up-regulation was confirmed by immunoblotting and real-time quantitative RT-PCR analysis. In addition to A549 cell line, primary lung cancer tissues also expressed higher level of LARS1 mRNA than their normal counter tissues. To explore the oncogenic potential of LARS1 over-expression in lung cancer, we knocked-down LARS1 by treating siRNA and observed the tumor behavior. LARS1 knock-down cells showed reduced ability to migrate through transwell membrane and to form colonies in both soft agar and culture plate. Taken together, these findings suggest that LARS1 may play roles in migration and growth of lung cancer cells, which suggest its potential implication in lung tumorigenesis.
PMCID: PMC2679304  PMID: 18446061
amino acyl-tRNA synthetases; cell movement; cell proliferation; leucine-tRNA ligase; lung neoplasms; oncogenes; RNA, small interfering
20.  IL-17 induces the production of IL-16 in rheumatoid arthritis 
Experimental & Molecular Medicine  2008;40(2):237-245.
The purpose of this study was to investigate the expression of IL-16 in the rheumatoid synovium and the role of inflammatory cytokines and Toll-like receptor (TLR) ligands in IL-16 production by fibroblastlike synoviocytes (FLS) of rheumatoid arthritis (RA) patients. Immunohistochemical staining was performed with a monoclonal antibody to IL-16 in synovial tissues from patients with RA and likewise in patients with osteoarthritis (OA). FLS were isolated from RA synovial tissues and stimulated with IL-15, IL-1β, IFN-γ, and IL-17. The IL-16 mRNA level was assessed by semiquantitative RT-PCR and real time (RT) PCR and a comparison was made between IL-16 mRNA levels produced by RA-FLS and OA-FLS. Production of IL-16 was identified by a western blot assay, and IL-16 production after stimulation by specific ligands of TLR2 and TLR4 was assessed by RT-PCR. While immunohistochemical staining demonstrated strong expression of IL-16 mRNA in synovial tissues from patients with RA, similar findings were not present in the OA group. Moreover, mRNA expression of IL-16 by RA-FLS increased after treatment with IL-17 but not with IL-15, IL-1β, and IFN-γ. Specifically, IL-17 increased IL-16 mRNA level by RA-FLS and peripheral blood mononuclear cells in a dose-dependent manner. However, IL-17 did not stimulate IL-16 production in OA-FLS. Peptidoglycan, a selective TLR2 ligand, also increased production of IL-16 by RA-FLS dosedependently, whereas LPS, a selective TLR4 ligand, had no such stimulatory effect. The results from our data demonstrate that IL-17 and TLR2 ligands stimulate the production of IL-16 by RA-FLS.
PMCID: PMC2679298  PMID: 18446062
interleukin-16; interleukin-17; rheumatoid arthritis; synovial membrane; Toll-like receptors
21.  Dysfunctional interferon-α production by peripheral plasmacytoid dendritic cells upon Toll-like receptor-9 stimulation in patients with systemic lupus erythematosus 
It is well known that interferon (IFN)-α is important to the pathogenesis of systemic lupus erythematosus (SLE). However, several reports have indicated that the number of IFN-α producing cells are decreased or that their function is defective in patients with SLE. We studied the function of plasmacytoid dendritic cells (pDCs) under persistent stimulation of Toll-like receptor (TLR)9 via a TLR9 ligand (CpG ODN2216) or SLE serum.
The concentrations of IFN-α were determined in serum and culture supernatant of peripheral blood mononuclear cells (PBMCs) from SLE patients and healthy controls after stimulation with CpG ODN2216 or SLE serum. The numbers of circulating pDCs were analyzed by fluoresence-activated cell sorting analysis. pDCs were treated with CpG ODN2216 and SLE serum repeatedly, and levels of produced IFN-α were measured. The expression of IFN-α signature genes and inhibitory molecules of TLR signaling were examined in PBMCs from SLE patients and healthy control individuals.
Although there was no significant difference in serum concentration of IFN-α and number of circulating pDCs between SLE patients and healthy control individuals, the IFN-α producing capacity of PBMCs was significantly reduced in SLE patients. Interestingly, the degree which TLR9 ligand-induced IFN-α production in SLE PBMCs was inversely correlated with the SLE serum-induced production of IFN-α in healthy PMBCs. Because repeated stimulation pDCs with TLR9 ligands showed decreased level of IFN-α production, continuous TLR9 stimulation may lead to decreased production of IFN-α in SLE PBMCs. In addition, PBMCs isolated from SLE patients exhibited higher expression of IFN-α signature genes and inhibitory molecules of TLR signaling, indicating that these cells had already undergone IFN-α stimulation and had become desensitized to TLR signaling.
We suggest that the persistent presence of endogenous IFN-α inducing factors induces TLR tolerance in pDCs of SLE patients, leading to impaired production of IFN-α.
PMCID: PMC2453773  PMID: 18321389
22.  Rituximab-CHOP Induced Interstitial Pneumonitis in Patients with Disseminated Extranodal Marginal Zone B Cell Lymphoma 
Yonsei Medical Journal  2008;49(1):155-158.
A 69-year-old male was diagnosed in February 2004 with stage IV extranodal marginal zone B cell lymphoma involving the mediastinal nodes, lung parenchyma and bone marrow with high LDH. Shortness of breath developed following the 5th course of Rituximab-CHOP chemotherapy (cyclophosphamide, Vincristine, Doxorubicin, Prednisolone). Bronchoscopy guided transbronchial lung biopsy revealed interstitial thickening and type II pneumocyte activation, compatible with interstitial pneumonitis. After treatment with prednisolone a complete resolution of the dyspnea was observed. The patient was well on routine follow-up at the outpatient clinic, with no progression of lymphoma or interstitial pneumonitis.
PMCID: PMC2615269  PMID: 18306483
Interstitial pneumonitis; rituximab; lymphoma
23.  Cryptococcal Meningitis Presenting with Isolated Sixth Cranial Nerve Palsy in a Patient with Systemic Lupus Erythematosus 
Journal of Korean Medical Science  2008;23(1):153-155.
Cryptococcal meningitis is a rare complication of systemic lupus erythematosus (SLE). The nonspecific neurologic findings associated with this infection delays accurate diagnosis because initial neuropsychiatric manifestations of SLE are in instances indistinguishable from that of crytococcal meningitis. We report a case of cryptococcal meningitis presenting with unilateral sixth cranial nerve palsy in a male patient with SLE, which was successfully treated with antifungal agents.
PMCID: PMC2526483  PMID: 18303219
Lupus Erythematosus, Systemic; Meningitis, Cryptococcal; Abducens Nerve Palsy
24.  Examining the effect of linkage disequilibrium between markers on the Type I error rate and power of nonparametric multipoint linkage analysis of two-generation and multigenerational pedigrees in the presence of missing genotype data 
Genetic epidemiology  2008;32(1):41-51.
Since most multipoint linkage analysis programs currently assume linkage equilibrium (LE) between markers when inferring parental haplotypes, ignoring linkage disequilibrium (LD) may inflate the Type I error rate. We investigated the effect of LD on the Type I error rate and power of nonparametric multipoint linkage analysis of two-generation and multigenerational multiplex families. Using genome wide single nucleotide polymorphism (SNP) data from the Collaborative Study of the Genetics of Alcoholism (COGA), we modified the original dataset into 30 total data sets in order to consider 6 different patterns of missing data for 5 different levels of SNP density. To assess power, we designed simulated traits based on existing marker genotypes. For the Type I error rate, we simulated 1,000 qualitative traits from random distributions, unlinked to any of the marker data. Overall, the different levels of SNP density examined here had only small effects on power (except sibpair data). Missing data had a substantial effect on power, with more completely genotyped pedigrees yielding the highest power (except sibpair data). Most of the missing data patterns did not cause large increases in the Type I error rate if the SNP markers were more than 0.3 cM apart. However, in a dense 0.25 cM map, removing genotypes on founders and/or founders and parents in the middle generation caused substantial inflation of the Type I error rate, which corresponded to the increasing proportion of persons with missing data. Results also showed that long high-LD blocks have severe effects on Type I error rates.
PMCID: PMC2216429  PMID: 17685456
SNPs; Type I error rate; False Positives; Linkage Disequilibrium; Pedigree Structure
25.  Indoleamine 2,3-dioxygenase-expressing dendritic cells are involved in the generation of CD4+CD25+ regulatory T cells in Peyer's patches in an orally tolerized, collagen-induced arthritis mouse model 
The present study was devised to understand the role of systemic indoleamine 2,3-dioxygenase (IDO) in the tolerance induction for orally tolerized mice in collagen-induced arthritis (CIA). We examined whether IDO-expressing dendritic cells (DCs) are involved in the generation of CD4+CD25+ regulatory T cells during the induction of oral tolerance in a murine CIA model.
Type II collagen was fed six times to DBA/1 mice beginning 2 weeks before immunization, and the effect on arthritis was assessed. To examine the IDO expression, the DCs of messenger RNA and protein were analyzed by RT-PCR and Flow cytometry. In addition, a proliferative response assay was also carried out to determine the suppressive effects of DCs through IDO. The ability of DCs expressing IDO to induce CD4+CD25+ T regulatory cells was examined.
CD11c+ DCs in Peyer's patches from orally tolerized mice expressed a higher level of IDO than DCs from nontolerized CIA mice. IDO-expressing CD11c+ DCs were involved in the suppression of type II collagen-specific T-cell proliferation and in the downregulation of proinflammatory T helper 1 cytokine production. The suppressive effect of IDO-expressing CD11c+ DCs was mediated by Foxp3+CD4+CD25+ regulatory T cells.
Our data suggest that tolerogenic CD11c+ DCs are closely linked with the induction of oral tolerance through an IDO-dependent mechanism and that this pathway may provide a new therapeutic modality to treat autoimmune arthritis.
PMCID: PMC2374459  PMID: 18221522

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