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Isolation of Streptomycin-Resistant Erwinia pyrifoliae in Korea. PLANT DISEASE 2023; 107:616-619. [PMID: 35852904 DOI: 10.1094/pdis-03-22-0553-sc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
As a black shoot blight disease-causing agent, Erwinia pyrifoliae was first reported in 1995 in Korea. A total of 101 isolates of E. pyrifoliae were isolated from samples showing bacterial symptoms collected from apple and pear orchards between 2020 and 2021. These isolates were screened for streptomycin resistance, with one from an orchard in Gwangju showing resistance at 100 μg/ml streptomycin. This streptomycin-resistant E. pyrifoliae (EpSmR) isolate was identified via polymerase chain reaction amplification of the strA/strB gene and an internal region of the ribosomal rpsL gene containing codon 43. EpSmR has a point mutation that altered this codon from lysine (AAA) to threonine (ACA). The strA and strB genes were not identified in EpSmR. EpSmR showed a high resistance to streptomycin (>50,000 μg/ml). This is the first study reporting EpSmR, which emerged due to a mutation in codon 43 of the rpsL gene.
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Effect of Second-Hand Smoke Exposure on Establishing Urinary Cotinine-Based Optimal Cut-Off Values for Smoking Status Classification in Korean Adults. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19137971. [PMID: 35805637 PMCID: PMC9265992 DOI: 10.3390/ijerph19137971] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 06/26/2022] [Accepted: 06/27/2022] [Indexed: 12/03/2022]
Abstract
Regulations for banning smoking in indoor public places and workplaces have increased worldwide in recent years. A consecutive Korean National Health and Nutrition Examination Survey (KNHANES) between 2008 and 2018 showed a trend toward significant decreases in self-reported tobacco smoke exposure and measured urinary cotinine concentrations. We established and compared each optimal cut-off value for assessing the effect of second-hand smoke (SHS) exposure on establishing urinary cotinine-based cut-off values for smoking status classification in a population setting controlled for racial and cultural diversity, using four KNHANES datasets consisting of the 2008, 2011, 2014, and 2018 surveys. A total of 18,229 Korean participants aged >19 years with measured urinary cotinine concentrations were enrolled. Self-reports of current smoking status showed that the prevalence of current smokers decreased from 22.9% to 18.2% between 2008 and 2018. During this period, the median value of urinary cotinine in nonsmokers decreased from 5.86 µg/L to 0.48 µg/L, whereas the median value showed no remarkable decrease in current smokers. The AUC-based optimal cut-off values of urinary cotinine concentration for distinguishing current smokers from nonsmokers decreased from 86.5 µg/L to 11.5 µg/L. Our study showed that decreased SHS exposure would result in decreased optimal cut-off values for distinguishing current smokers from nonsmokers. In addition, the study suggests that the range of urinary cotinine concentration to define SHS exposure for the trend monitoring of populationof SHS exposure is appropriate between 0.30 µg/L and 100 µg/L. In addition, our study showed the importance of determination of cotinine concentration, which would have allowed us to avoid mistakes in qualification to the study group in an increased use of e-cigarette setting.
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Genome-wide analysis in 756,646 individuals provides first genetic evidence that ACE2 expression influences COVID-19 risk and yields genetic risk scores predictive of severe disease. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2021. [PMID: 33619501 PMCID: PMC7899471 DOI: 10.1101/2020.12.14.20248176] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
SARS-CoV-2 enters host cells by binding angiotensin-converting enzyme 2 (ACE2). Through a genome-wide association study, we show that a rare variant (MAF = 0.3%, odds ratio 0.60, P=4.5×10-13) that down-regulates ACE2 expression reduces risk of COVID-19 disease, providing human genetics support for the hypothesis that ACE2 levels influence COVID-19 risk. Further, we show that common genetic variants define a risk score that predicts severe disease among COVID-19 cases.
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Salinomycin suppresses TGF-β1-induced EMT by down-regulating MMP-2 and MMP-9 via the AMPK/SIRT1 pathway in non-small cell lung cancer. Int J Med Sci 2021; 18:715-726. [PMID: 33437206 PMCID: PMC7797542 DOI: 10.7150/ijms.50080] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 10/15/2020] [Indexed: 12/13/2022] Open
Abstract
Salinomycin (Sal) is a recently identified anti-tumor drug for treating several types of solid tumor; however, its effects on the migratory and invasive properties of non-small cell lung cancer (NSCLC) remain unclear. This study investigated the inhibitory effect underlying mechanisms of Salon transforming growth factor-β1 (TGF-β1)-induced epithelial-to-mesenchymal transition (EMT) and cell migration. Sal solidly blocked cell migration and invasion enhancement by TGF-β1-induced EMT, through recovering E-cadherin loss and suppressing mesenchymal markers induction, as well as TGF-β1-mediated AMPK/SIRT signaling activity upregulation. The pharmacologic inhibition or knockdown of AMPK or SIRT1 can act synergistically with Sal to inhibit TGF-β1-induced MMP-2 and MMP-9. In contrast, AMPK or SIRT1 upregulation can protect against TGF-β1-induced MMP-2 and MMP-9 inhibition by Sal. Next we demonstrated that the MMP-2 and MMP-9 knockdown can act synergistically with Sal to inhibit TGF-β1-induced EMT. Moreover, treatment of PMA of MMP activator increased TGF-β1-induced MMP-2 and MMP-9, even with Sal. Our results demonstrate that Sal suppresses TGF-β1-induced EMT by downregulating MMP-2 and MMP-9 through the AMPK/SIRT pathway, thereby inhibiting lung cancer cell migration and invasion.
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P4401Cardioprotective effect of substance P in a porcine model of acute myocardial infarction. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy563.p4401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Expression Profile of Three Splicing Factors in Pleural Cells Based on the Underlying Etiology and Its Clinical Values in Patients with Pleural Effusion. Transl Oncol 2018; 11:147-156. [PMID: 29288986 PMCID: PMC6002346 DOI: 10.1016/j.tranon.2017.12.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 12/07/2017] [Indexed: 11/20/2022] Open
Abstract
Splicing factors (SFs) are involved in oncogenesis or immune modulation, the common underlying processes giving rise to pleural effusion (PE). The expression profiles of three SFs (HNRNPA1, SRSF1, and SRSF3) and their clinical values have never been assessed in PE. The three SFs (in pellets of PE) and conventional tumor markers were analyzed using PE samples in patients with PE (N = 336). The sum of higher-molecular weight (Mw) forms of HNRNPA1 (Sum-HMws-HNRNPA1) and SRSF1 (Sum-HMws-SRSF1) and SRSF3 levels were upregulated in malignant PE (MPE) compared to benign PE (BPE); they were highest in cytology-positive MPE, followed by tuberculous PE and parapneumonic PE. Meanwhile, the lowest-Mw HNRNPA1 (LMw-HNRNPA1) and SRSF1 (LMw-SRSF1) levels were not upregulated in MPE. Sum-HMws-HNRNPA1, Sum-HMws-SRSF1, and SRSF3, but neither LMw-HNRNPA1 nor LMw-SRSF1, showed positive correlations with cancer cell percentages in MPE. The detection accuracy for MPE was high in the order of carcinoembryonic antigen (CEA, 85%), Sum-HMws-HNRNPA1 (76%), Sum-HMws-SRSF1 (68%), SRSF3, cytokeratin-19 fragments (CYFRA 21-1), LMw-HNRNPA1, and LMw-SRSF1. Sum-HMws-HNRNPA1 detected more than half of the MPE cases that were undetected by cytology and CEA. Sum-HMws-HNRNPA1, but not other SFs or conventional tumor markers, showed an association with longer overall survival among patients with MPE receiving chemotherapy. Our results demonstrated different levels of the three SFs with their Mw-specific profiles depending on the etiology of PE. We suggest that Sum-HMws-HNRNPA1 is a supplementary diagnostic marker for MPE and a favorable prognostic indicator for patients with MPE receiving chemotherapy.
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Shikonin-induced necroptosis is enhanced by the inhibition of autophagy in non-small cell lung cancer cells. J Transl Med 2017; 15:123. [PMID: 28569199 PMCID: PMC5452303 DOI: 10.1186/s12967-017-1223-7] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 05/23/2017] [Indexed: 01/03/2023] Open
Abstract
Background Shikonin, a natural naphthoquinone pigment purified from Lithospermum erythrorhizon, induces necroptosis in various cancer types, but the mechanisms underlying the anticancer activity of shikonin in lung cancer are not fully understood. This study was designed to clarify whether shikonin causes necroptosis in non-small cell lung cancer (NSCLC) cells and to investigate the mechanism of action. Methods Multiplex and caspase 8 assays were used to analyze effect of shikonin on A549 cells. Cytometry with annexin V/PI staining and MTT assays were used to analyze the mode of cell death. Western blotting was used to determine the effect of shikonin-induced necroptosis and autophagy. Xenograft and orthotopic models with A549 cells were used to evaluate the anti-tumor effect of shikonin in vivo. Results Most of the cell death induced by shikonin could be rescued by the specific necroptosis inhibitor necrostatin-1, but not by the general caspase inhibitor Z-VAD-FMK. Tumor growth was significantly lower in animals treated with shikonin than in the control group. Shikonin also increased RIP1 protein expression in tumor tissues. Autophagy inhibitors, including methyladenine (3-MA), ATG5 siRNA, and bafilomycin A, enhanced shikonin-induced necroptosis, whereas RIP1 siRNA had no effect on the apoptotic potential of shikonin. Conclusions Our data indicated that shikonin treatment induced necroptosis and autophagy in NSCLC cells. In addition, the inhibition of shikonin-induced autophagy enhanced necroptosis, suggesting that shikonin could be a novel therapeutic strategy against NSCLC.
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SRSF5: a novel marker for small-cell lung cancer and pleural metastatic cancer. Lung Cancer 2016; 99:57-65. [DOI: 10.1016/j.lungcan.2016.05.018] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 05/23/2016] [Accepted: 05/25/2016] [Indexed: 11/26/2022]
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Inhibition of autophagy potentiates pemetrexed and simvastatin-induced apoptotic cell death in malignant mesothelioma and non-small cell lung cancer cells. Oncotarget 2016; 6:29482-96. [PMID: 26334320 PMCID: PMC4745741 DOI: 10.18632/oncotarget.5022] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 08/10/2015] [Indexed: 12/21/2022] Open
Abstract
Pemetrexed, a multitarget antifolate used to treat malignant mesothelioma and non-small cell lung cancer (NSCLC), has been shown to stimulate autophagy. In this study, we determined whether autophagy could be induced by pemetrexed and simvastatin cotreatment in malignant mesothelioma and NSCLC cells. Furthermore, we determined whether inhibition of autophagy drives apoptosis in malignant mesothelioma and NSCLC cells. Malignant mesothelioma MSTO-211H and A549 NSCLC cells were treated with pemetrexed and simvastatin alone and in combination to evaluate their effect on autophagy and apoptosis. Cotreatment with pemetrexed and simvastatin induced greater caspase-dependent apoptosis and autophagy than either drug alone in malignant mesothelioma and NSCLC cells. 3-Methyladenine (3-MA), ATG5 siRNA, bafilomycin A, and E64D/pepstatin A enhanced the apoptotic potential of pemetrexed and simvastatin, whereas rapamycin and LY294002 attenuated their induction of caspase-dependent apoptosis. Our data indicate that pemetrexed and simvastatin cotreatment augmented apoptosis and autophagy in malignant mesothelioma and NSCLC cells. Inhibition of pemetrexed and simvastatin-induced autophagy was shown to enhance apoptosis, suggesting that this could be a novel therapeutic strategy against malignant mesothelioma and NSCLC.
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Comparative expression patterns and diagnostic efficacies of SR splicing factors and HNRNPA1 in gastric and colorectal cancer. BMC Cancer 2016; 16:358. [PMID: 27282379 PMCID: PMC4901428 DOI: 10.1186/s12885-016-2387-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 05/26/2016] [Indexed: 01/14/2023] Open
Abstract
Background Serine/arginine-rich splicing factors (SRSFs) and HNRNPA1 have oncogenic properties. However, their proteomic expressions and practical priority in gastric cancer (GC) and colorectal cancer (CRC) are mostly unknown. To apply SFs in clinics, effective marker selection and characterization of properties in the target organ are essential. Methods We concurrently analyzed SRSF1, 3, and 5–7, and HNRNPA1, together with the conventional tumor marker carcinoembryonic antigen (CEA), in stomach and colorectal tissue samples (n = 420) using semiquantitative immunoblot, subcellular fractionation, and quantitative real-time polymerase chain reaction methods. Results In the semiquantitative immunoblot analysis, HNRNPA1 and SRSF7 levels were significantly higher in GC than in gastric normal mucosa, and SRSF7 levels were higher in intestinal-type compared with diffuse-type of gastric adenocarcinoma. Of the SFs, only HNRNPA1 presented greater than 50 % upregulation (cancer/normal mucosa > 2-fold) incidences and CEA-comparable, acceptable (>70 %) detection accuracy (74 %) for GC. All SF protein levels were significantly higher in CRC than in colorectal normal mucosa, and HNRNPA1 levels were higher in low-stage CRC compared with high-stage CRC. Among the SFs, HNRNPA1 and SRSF3 presented the two highest upregulation incidences (88 % and 74 %, respectively) and detection accuracy (90 % and 84 %, respectively) for CRC. The detection accuracy of HNRNPA1 was comparable to that of CEA in low (≤ II)-stage CRC but was inferior to that of CEA in high (>II)-stage CRC. Extranuclear distributions of HNRNPA1 and SRSF6 (cytosol/microsome) differed from those of other SRSFs (membrane/organelle) in both cancers. In an analysis of the six SF mRNAs, all mRNAs presented unacceptable detection accuracies (≤70 %) in both cancers, and all mRNAs except SRSF6 were disproportionate to the corresponding protein levels in GC. Conclusion Our results provide a comprehensive insight into the six SF expression profiles in GC and indicate that, among the SFs, HNRNPA1, but not HNRNPA1 mRNA, is the most effective, novel GC marker. Regardless of the good to excellent detection accuracy of SRSF3 and HNRNPA1 in CRC, the SFs have lower practical priority than CEA, especially for high-stage CRC detection.
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Antioxidative Activity after Rosuvastatin Treatment in Patients with Stable Ischemic Heart Disease and Decreased High Density Lipoprotein Cholesterol. Korean Circ J 2016; 46:309-14. [PMID: 27275167 PMCID: PMC4891595 DOI: 10.4070/kcj.2016.46.3.309] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 08/31/2015] [Accepted: 10/06/2015] [Indexed: 11/11/2022] Open
Abstract
Background and Objectives The clinical significance of statin-induced high-density lipoprotein cholesterol (HDL-C) changes is not well known. We investigated whether rosuvastatin-induced HDL-C changes can influence the anti-oxidative action of high-density lipoprotein particle. Subjects and Methods A total of 240 patients with stable ischemic heart disease were studied. Anti-oxidative property was assessed by paraoxonase 1 (PON1) activity. We compared the lipid profile and PON1 activity at baseline and at 8 weeks after rosuvastatin 10 mg treatment. Results Rosuvastatin treatment increased the mean HDL-C concentration by 1.9±9.2 mg/dL (6.4±21.4%). HDL-C increased in 138 patients (57.5%), but decreased in 102 patients (42.5%) after statin treatment. PON1 activity increased to 19.1% in all patients. In both, the patients with increased HDL-C and with decreased HDL-C, PON1 activity significantly increased after rosuvastatin treatment (+19.3% in increased HDL-C responder; p=0.018, +18.8% in decreased HDL-C responder; p=0.045 by paired t-test). Baseline PON1 activity modestly correlated with HDL-C levels (r=0.248, p=0.009); however, the PON1 activity evaluated during the course of the treatment did not correlate with HDL-C levels (r=0.153, p=0.075). Conclusion Rosuvastatin treatment improved the anti-oxidative properties as assessed by PON1 activity, regardless of on-treatment HDL-C levels, in patients with stable ischemic heart disease.
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TAGLN2 regulates T cell activation by stabilizing the actin cytoskeleton at the immunological synapse. ACTA ACUST UNITED AC 2015; 209:143-62. [PMID: 25869671 PMCID: PMC4395477 DOI: 10.1083/jcb.201407130] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
TAGLN2 stabilizes cortical F-actin and thereby maintains F-actin contents at the immunological synapse, which allows T cell activation following T cell receptor stimulation. The formation of an immunological synapse (IS) requires tight regulation of actin dynamics by many actin polymerizing/depolymerizing proteins. However, the significance of actin stabilization at the IS remains largely unknown. In this paper, we identify a novel function of TAGLN2—an actin-binding protein predominantly expressed in T cells—in stabilizing cortical F-actin, thereby maintaining F-actin contents at the IS and acquiring LFA-1 (leukocyte function-associated antigen-1) activation after T cell receptor stimulation. TAGLN2 blocks actin depolymerization and competes with cofilin both in vitro and in vivo. Knockout of TAGLN2 (TAGLN2−/−) reduced F-actin content and destabilized F-actin ring formation, resulting in decreased cell adhesion and spreading. TAGLN2−/− T cells displayed weakened cytokine production and cytotoxic effector function. These findings reveal a novel function of TAGLN2 in enhancing T cell responses by controlling actin stability at the IS.
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Pemetrexed induces apoptosis in malignant mesothelioma and lung cancer cells through activation of reactive oxygen species and inhibition of sirtuin 1. Oncol Rep 2015; 33:2411-9. [PMID: 25738249 DOI: 10.3892/or.2015.3830] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 02/09/2015] [Indexed: 11/05/2022] Open
Abstract
Pemetrexed is a multitargeted antifolate used for the treatment of malignant mesothelioma and non-small cell lung cancer (NSCLC). However, the mechanism by which pemetrexed induces apoptosis remains unclear. In the present study, we investigated the involvement of reactive oxygen species (ROS) and sirtuin 1 (SIRT1) in pemetrexed-induced apoptosis in MSTO-211 malignant mesothelioma cells and A549 NSCLC cells. Pemetrexed enhanced caspase-dependent apoptosis, induced intracellular ROS generation, and downregulated SIRT1 in the MSTO-211 and A549 cells. Pemetrexed-induced apoptosis, which was prevented by pretreatment with N-acetyl-cysteine (NAC), was mediated by effects on the mitochondria, including mitochondrial membrane potential transition (MPT) and cytosolic release of cytochrome c, and also involved regulation of SIRT1 expression. Interference with SIRT1 expression using siRNA enhanced pemetrexed-induced apoptosis through mitochondrial dysfunction and ROS generation, whereas resveratrol, an activator of SIRT1, protected against pemetrexed-induced apoptosis. These results show that pemetrexed induces apoptosis in MSTO-211 mesothelioma cells and A549 NSCLC cells through mitochondrial dysfunction mediated by ROS accumulation and SIRT1 downregulation.
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Chloroform fraction of Euphorbia maculata has antiplatelet activity via suppressing thromboxane B2 formation. Mol Med Rep 2015; 11:4255-61. [PMID: 25672843 DOI: 10.3892/mmr.2015.3319] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 01/15/2015] [Indexed: 11/06/2022] Open
Abstract
Euphorbia maculata (EM) is a traditionally used antidiarrheal, antibacterial, antifungal and antioxidant agent. However, the effects of EM on platelet activity remain to be elucidated. Therefore, the present study investigated the antiplatelet effect of various EM extract fractions on platelet aggregation in rats. The antiplatelet activity of the EM fractions on collagen or adenosine diphosphate (ADP)‑induced platelet aggregation was evaluated in vitro and ex vivo. Thromboxane B2 (TXB2) formation, rat‑tail bleeding time and coagulation time were also measured. Among the fractions, the chloroform fraction of EM (CFEM) significantly inhibited ADP‑induced platelet aggregation in vitro. Furthermore, oral administration of 50 mg/kg CFEM to rats significantly reduced ADP‑induced platelet aggregation without increasing the tail bleeding time or coagulation time. In addition, EM significantly inhibited the level of TXB2 formation in a dose‑dependent manner. These results suggest that CFEM exhibits antiplatelet activity, without causing bleeding, via the suppression of TXB2 formation. CFEM may be a type of food which has the potential for preventing cardiovascular disease.
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Pleural fluid characteristics of pleuropulmonary paragonimiasis masquerading as pleural tuberculosis. Korean J Intern Med 2015; 30:56-61. [PMID: 25589836 PMCID: PMC4293564 DOI: 10.3904/kjim.2015.30.1.56] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 05/27/2014] [Accepted: 07/10/2014] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND/AIMS Pleuropulmonary paragonimiasis produces no specific symptoms or radiologic findings, allowing for the possibility of misdiagnosis. We evaluated the specific clinical and pleural fluid features of pleuropulmonary paragonimiasis masquerading as pleural tuberculosis. METHODS We retrospectively analyzed the clinical and radiologic characteristics of 20 patients diagnosed with pleuropulmonary paragonimiasis between 2001 and 2011. RESULTS In total, 17 patients presented with respiratory symptoms, including dyspnea (30%), hemoptysis (20%), cough (20%), and pleuritic chest pain (15%). Chest radiographs revealed intrapulmonary parenchymal lesions, including air-space consolidation (30%), nodular opacities (20%), cystic lesions (15%), ground-glass opacities (10%), and pneumothorax (5%). A pleural fluid examination revealed eosinophilia, low glucose levels, and high lactate dehydrogenase (LDH) levels in 87%, 76%, and 88% of the patients, respectively. These traits helped to distinguish pleuropulmonary paragonimiasis from other pleural diseases such as parapneumonic effusion, malignancy, and pleural tuberculosis. CONCLUSIONS Pleuropulmonary paragonimiasis is often initially misdiagnosed as other pleural diseases. Therefore, it is important to establish the correct diagnosis. In patients with unexplained pleural effusion living in paragonimiasis-endemic areas, pleural fluid obtained by thoracentesis should be examined to distinguish pleuropulmonary paragonimiasis. When marked eosinophilia, high LDH levels, and low glucose levels are identified in pleural fluid, physicians could consider a diagnosis of pleuropulmonary paragonimiasis.
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Aberrant proteomic expression of NSRP70 and its clinical implications and connection to the transcriptional level in adult acute leukemia. Leuk Res 2014; 38:1252-9. [PMID: 25176346 DOI: 10.1016/j.leukres.2014.08.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 08/02/2014] [Accepted: 08/03/2014] [Indexed: 11/30/2022]
Abstract
We investigated three splicing factor proteins (SFPs; NSRP70, SRSF1, and HNRNPA1) in 187 adults with and without acute leukemia (AL). We showed that NSRP70 is a novel lymphoblastic AL (ALL) surrogate marker, which presented excellent diagnostic accuracy (92%) and disappeared during remission. Its highest molecular weight form, but not total amount, was associated with adverse genetic abnormalities in myeloid AL (AML). Furthermore, we identified that these SFPs were more prevalent in ALL than in AML; were not correlated with their mRNA levels; and their formations in AL may occur without coding mutations and relate to post-translational modifications.
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Enhanced apoptosis by pemetrexed and simvastatin in malignant mesothelioma and lung cancer cells by reactive oxygen species-dependent mitochondrial dysfunction and Bim induction. Int J Oncol 2014; 45:1769-77. [PMID: 25096993 DOI: 10.3892/ijo.2014.2584] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 07/16/2014] [Indexed: 11/06/2022] Open
Abstract
Pemetrexed is a multitarget antifolate currently used for the treatment of malignant mesothelioma and non-small cell lung cancer (NSCLC). Statins, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors used primarily for hyperlidpidemia, have been studied for their antiproliferative and pro-apoptotic effects. However, the effects of simvastatin on pemetrexed-induced apoptosis have not been investigated. In this study, we investigated whether combination treatment with pemetrexed and simvastatin potentiates the apoptotic activity above that is seen with either drug alone in malignant mesothelioma and NSCLC cells. We found that the combination of pemetrexed and simvastatin induced more extensive caspase-dependent apoptosis than either drug alone in malignant mesothelioma cells (MSTO-211) or NSCLC cells (A549). In addition, reactive oxygen species (ROS) generation in cells treated with both pemetrexed and simvastatin was markedly increased compared to cells treated with either pemetrexed or simvastatin alone. Combination treatment also increased the loss of mitochondrial membrane potential, increased cytosolic release of cytochrome c, and altered expression of inhibitor of apoptosis proteins (IAP) and B-cell lymphoma-2 (Bcl-2) families of apoptosis related proteins. On the other hand, pretreatment with N-acetylcysteine (NAC) prevented apoptosis and mitochondrial dysfunction by pemetrexed and simvastatin. In addition, Bim siRNA conferred protection against apoptosis induced by pemetrexed and simvastatin. These results suggest that combination of pemetrexed and simvastatin potentiates their apoptotic activity beyond that of either drug alone in malignant mesothelioma and lung cancer cells. This activity is mediated through ROS-dependent mitochondrial dysfunction and Bim induction.
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Abstract
Clostridium difficile infection (CDI) is a common nosocomial infection. Lung cancer patients have a high risk of developing CDI because of continuous antibiotic treatment or chemotherapy, prolonged hospitalization, and general weakness. This study aimed to analyze predisposing or associated risk factors for CDI in lung cancer patients receiving chemotherapy. This study was a retrospective review of 188 lung cancer patients who were admitted to the Wonkwang University Hospital between 2008 and 2009. Of the 188 patients, 44 were diagnosed with CDI. The albumin levels were significantly lower and the performance status (PS) score was significantly higher in lung cancer patients with CDI than in those without CDI (P < 0.05). In conclusion, clinicians should consider the possibility of CDI occurrence in lung cancer patients receiving chemotherapy, particularly in those with low albumin levels and high PS scores, because most lung cancer patients have a high risk of developing CDI.
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Effect of simvastatin on the resistance to EGFR tyrosine kinase inhibitors in a non-small cell lung cancer with the T790M mutation of EGFR. Exp Cell Res 2014; 323:288-96. [PMID: 24631288 DOI: 10.1016/j.yexcr.2014.02.026] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 02/21/2014] [Accepted: 02/22/2014] [Indexed: 10/25/2022]
Abstract
Although non-small cell lung cancer (NSCLC) tumors with activating mutations in the epidermal growth factor receptor (EGFR) are highly responsive to EGFR tyrosine kinase inhibitors (TKIs) including gefitinib and erlotinib, development of acquired resistance is almost inevitable. Statins show antitumor activity, but it is unknown whether they can reverse EGFR-TKIs resistance in NSCLC with the T790M mutation of EGFR. This study investigated overcoming resistance to EGFR-TKI using simvastatin. We demonstrated that addition of simvastatin to gefitinib enhanced caspase-dependent apoptosis in T790M mutant NSCLC cells. Simvastatin also strongly inhibited AKT activation, leading to suppression of β-catenin activity and the expression of its targets, survivin and cyclin D1. Both insulin treatment and AKT overexpression markedly increased p-β-catenin and survivin levels, even in the presence of gefitinib and simvastatin. However, inhibition of AKT by siRNA or LY294002 treatment decreased p-β-catenin and survivin levels. To determine the role of survivin in simvastatin-induced apoptosis of gefitinib-resistant NSCLC, we showed that the proportion of apoptotic cells following treatment with survivin siRNA and the gefitinib-simvastatin combination was greater than the theoretical additive effects, whereas survivin up-regulation could confer protection against gefitinib and simvastatin-induced apoptosis. Similar results were obtained in erlotinib and simvastatin-treated HCC827/ER cells. These findings suggest that survivin is a key molecule that renders T790M mutant NSCLC cells resistant to apoptosis induced by EGFR-TKIs and simvastatin. Overall, these data indicate that simvastatin may overcome EGFR-TKI resistance in T790M mutant NSCLCs via an AKT/β-catenin signaling-dependent down-regulation of survivin and apoptosis induction.
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The prognosis of patients with lung cancer admitted to the medical intensive care unit. Asia Pac J Clin Oncol 2013; 12:e118-24. [PMID: 24289233 DOI: 10.1111/ajco.12157] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
AIMS Lung cancer remains the leading cause of cancer mortality worldwide. Despite their poor prognosis, patients with lung cancer are increasingly being admitted to the medical intensive care unit (MICU) for treatment of critical illnesses. The aim of this study was to assess the outcome of patients with lung cancer who are admitted to an MICU and to identify the measurable predictors of their MICU outcome. METHODS We conducted retrospective analysis on 97 patients with lung cancer admitted to the MICU between 2007 and 2011. RESULTS The mean age ± standard deviation was 71.8 ± 6.8 years. Of the 97 patients (82 male), 73 patients (75%) had non-small cell lung cancer stage IIIB, IV and 24 patients (25%) had small cell lung cancer. The intensive care unit mortality and in-hospital mortality rates were 53.6 and 61.8%. The main reasons for MICU admission were pneumonia (n = 51) and complication of cancer management (n = 45). The predictors of poor MICU outcome were history of diabetes mellitus (P = 0.028), Acute Physiology and Chronic Health Evaluation II score (P = 0.018), need for mechanical ventilation (P = 0.014), use of vasoactive agents (P < 0.0001), the presence of acute renal failure (P < 0.0001) and presence of multiorgan failure (P < 0.0001). CONCLUSIONS We found that in-hospital mortality was not influenced by age, sex or performance status score of patients with lung cancer but increased with the severity of organ failure at MICU admission.
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Synergistic induction of apoptosis by sulindac and simvastatin in A549 human lung cancer cells via reactive oxygen species-dependent mitochondrial dysfunction. Int J Oncol 2013; 43:262-70. [PMID: 23661227 DOI: 10.3892/ijo.2013.1933] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Accepted: 04/15/2013] [Indexed: 11/05/2022] Open
Abstract
Prevention of lung cancer is more feasible and holds greater promise when different agents are used in combination to target multiple processes during carcinogenesis. The mechanisms by which non-steroidal anti-inflammatory drugs and statins inhibit cancer cell growth and induce apoptosis are not fully understood. This study was designed to investigate lung cancer chemoprevention through a mechanism-based approach using sulindac at low doses in combination with simvastatin. We found that sulindac-induced cytotoxicity was significantly enhanced in the presence of simvastatin. The combination of sulindac and simvastatin induced more extensive caspase-dependent apoptosis in A549 cells compared to that induced with either drug alone. The combination of sulindac and simvastatin also increased the loss of mitochondrial transmembrane potential (∆Ψm) and the cytosolic release of cytochrome c. In addition, ROS generation in cells treated with both sulindac and simvastatin was markedly increased compared to cells treated with either sulindac or simvastatin alone. The enhancement of ROS generation by sulindac and simvastatin was abrogated by pretreatment with NAC, which also prevented apoptosis and mitochondrial dysfunction induced by sulindac and simvastatin. These results suggest that sulindac and simvastatin-induced ROS generation in A549 lung cancer cells causes their accumulation in mitochondria, triggering the release of apoptogenic molecules from the mitochondria to the cytosol, and thus leading to caspase activation and cell death.
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Prx1 modulates the chemosensitivity of lung cancer to docetaxel through suppression of FOXO1-induced apoptosis. Int J Oncol 2013; 43:72-8. [PMID: 23615915 DOI: 10.3892/ijo.2013.1918] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2013] [Accepted: 04/09/2013] [Indexed: 12/22/2022] Open
Abstract
The expression levels of Prx1 are frequently elevated in several human cancers, including lung cancer and may confer increased resistance to treatment. In this study, we investigated the role of Prx1 in docetaxel-induced apoptosis in A549 lung cancer cells. To test whether Prx1 knockdown affected the sensitivity of A549 cells to docetaxel treatment, we generated short hairpin RNA (shRNA) constructs targeting Prx1 and analyzed the effect of Prx1 knockdown on growth and apoptosis. Tumor growth was evaluated in scrambled shRNA- or shPrx1-infected A549 cell tumors receiving docetaxel treatment. In addition, mechanistic information was gathered by western blot analysis from cell lysates of scrambled- and shPrx1-infected A549 cells pretreated with or without LY294002 and subsequently treated with docetaxel. We found that Prx1 knockdown resulted in enhanced docetaxel-induced cytotoxicity in a dose-dependent manner. In vivo, the growth rate of shPrx1-infected A549 tumors was significantly reduced compared to that of scrambled shRNA-infected A549 tumors. Prx1 knockdown also augmented the inhibitory effects of docetaxel on tumor growth. Prx1 knockdown increased the apoptotic potential through activation of the caspase cascade and suppressed docetaxel-induced phosphorylation of Akt and its substrate forkhead box O1 (FOXO1). Moreover, treatment with the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 reduced the phosphorylation of FOXO1 and increased the cytotoxicity of docetaxel in A549 cells. Our findings suggest that Prx1 may modulate the chemosensitivity of lung cancer to docetaxel through suppression of FOXO1-induced apoptosis.
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Diagnostic value and prognostic significance of pleural C-reactive protein in lung cancer patients with malignant pleural effusions. Yonsei Med J 2013; 54:396-402. [PMID: 23364973 PMCID: PMC3575996 DOI: 10.3349/ymj.2013.54.2.396] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
PURPOSE C-reactive protein (CRP) has been implicated in various inflammatory and advanced malignant states. Increased serum CRP (s-CRP) levels have been shown to be associated with independent prognostic factors for survival in patients with advanced lung cancer. However, only few studies have focused on the role of CRP in pleural effusions. This study aimed to evaluate the diagnostic and prognostic value of pleural CRP (p-CRP) in lung cancer patients with malignant pleural effusion (MPE). MATERIALS AND METHODS Pleural effusion (PE) samples were collected from patients with MPE (68 lung cancers; 12 extrathoracic tumors), and from 68 patients with various benign conditions (31 with pneumonia; 37 with tuberculosis). Concentrations of p- and s-CRP were measured by enzyme-linked immunosorbent assay. CRP level in pleural fluid and its association with survival were examined. RESULTS p-CRP levels correlated with s-CRP levels (r=0.82, p<0.0001). For the differential diagnosis of MPE and benign PE, the area under the receiver operating characteristic curve was greater for p-CRP (0.86) than for s-CRP (0.77). High p-CRP expression significantly correlated with shorter overall survival (p=0.006). P-CRP was independent prognostic factor significantly associated with overall survival on multivariated analysis (p=0.0001). The relative risk of death for lung cancer patients with high p-CRP levels was 3.909 (95% confidence interval, 2.000-7.639). CONCLUSION P-CRP is superior to s-CRP in determining pleural fluid etiology. Quantitative measurement of p-CRP might be a useful complementary diagnostic and prognostic test for lung cancer patients with MPE.
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Association between elevated pleural interleukin-33 levels and tuberculous pleurisy. Ann Lab Med 2012; 33:45-51. [PMID: 23301222 PMCID: PMC3535196 DOI: 10.3343/alm.2013.33.1.45] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 08/06/2012] [Accepted: 09/28/2012] [Indexed: 11/23/2022] Open
Abstract
Background Interferon-γ (IFN-γ) plays a crucial role in Mycobacterium tuberculosis induced pleural responses. Interleukin (IL)-33 up-regulates the production of IFN-γ. We aimed to identify whether an association between pleural IL-33 levels and tuberculous pleurisy exists and determine its diagnostic value. Methods Pleural IL-33, ST2 (a receptor of IL-33), adenosine deaminase (ADA), and IFN-γ, as well as serum IL-33 and ST2 were measured in 220 patients with pleural effusions (PEs). Patients with malignant (MPEs), parapneumonic (PPEs), tuberculous (TPEs), and cardiogenic (CPEs) pleural effusions were included. Results Pleural and serum IL-33 levels were highest or tended to be higher in patients with TPEs than in those with other types of PEs. The median pleural fluid-to-serum IL-33 ratio was higher in TPE cases (≥ 0.91) than in other PE cases (≤ 0.56). Pleural IL-33 levels correlated with those of pleural ADA and IFN-γ. However, the diagnostic accuracies of pleural IL-33 (0.74) and pleural fluid-to-serum IL-33 ratio (0.75) were lower than that of ADA (0.95) or IFN-γ (0.97). Pleural ST2 levels in patients with MPEs were higher than in patients with TPEs. Serum ST2 levels did not differ among the groups. Conclusions We identified an association between elevated pleural IL-33 levels and tuberculous pleurisy. However, we recommend conventional pleural markers (ADA or IFN-γ) as diagnostic markers of TPE.
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Serum YKL-40 levels correlate with infarct volume, stroke severity, and functional outcome in acute ischemic stroke patients. PLoS One 2012; 7:e51722. [PMID: 23272150 PMCID: PMC3522716 DOI: 10.1371/journal.pone.0051722] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Accepted: 11/05/2012] [Indexed: 12/22/2022] Open
Abstract
Background and Purpose YKL-40 is associated with various neurological disorders. However, circulatory YKL-40 levels early after onset of acute ischemic stroke (AIS) have not been systematically assessed. We aimed to identify the temporal changes and clinical usefulness of measuring serum YKL-40 immediately following AIS. Methods Serum YKL-40 and C-reactive protein (CRP) levels were monitored over time in AIS patients (n = 105) and compared with those of stroke-free controls (n = 34). Infarct volume and stroke severity (National Institutes of Health Stroke Scale; NIHSS) were measured within 48 hours of symptom onset, and functional outcome (modified Rankin Scale; mRS) was measured 3 months after AIS. Results Within 12 hours of symptom onset, levels of YKL-40 (251 vs. 41 ng/mL) and CRP (1.50 vs. 0.96 µg/mL) were elevated in AIS patients compared to controls. The power of YKL-40 for discriminating AIS patients from controls was superior to that of CRP (area under the curve 0.84 vs. 0.64) and YKL-40 (r = 0.26, P<0.001) but not CRP levels were correlated with mRS. On day 2 of admission (D2), YKL-40 levels correlated with infarct volume and NIHSS. High YKL-40 levels predicted poor functional outcome (odds ratio 5.73, P = 0.03). YKL-40 levels peaked on D2 and declined on D3, whereas CRP levels were highest on D3. Conclusions Our results demonstrate serial changes in serum YKL-40 levels immediately following AIS and provide the first evidence that it is a valid indicator of AIS extent and an early predictor of functional outcome.
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Vital roles of mTOR complex 2 in Notch-driven thymocyte differentiation and leukemia. J Biophys Biochem Cytol 2012. [DOI: 10.1083/jcb1972oia3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Abstract
Rictor is essential in Notch-driven T-ALL pathogenesis. Notch plays critical roles in both cell fate decisions and tumorigenesis. Notch receptor engagement initiates signaling cascades that include a phosphatidylinositol 3-kinase/target of rapamycin (TOR) pathway. Mammalian TOR (mTOR) participates in two distinct biochemical complexes, mTORC1 and mTORC2, and the relationship between mTORC2 and physiological outcomes dependent on Notch signaling is unknown. In this study, we report contributions of mTORC2 to thymic T-cell acute lymphoblastic leukemia (T-ALL) driven by Notch. Conditional deletion of Rictor, an essential component of mTORC2, impaired Notch-driven proliferation and differentiation of pre-T cells. Furthermore, NF-κB activity depended on the integrity of mTORC2 in thymocytes. Active Akt restored NF-κB activation, a normal rate of proliferation, and differentiation of Rictor-deficient pre-T cells. Strikingly, mTORC2 depletion lowered CCR7 expression in thymocytes and leukemic cells, accompanied by decreased tissue invasion and delayed mortality in T-ALL driven by Notch. Collectively, these findings reveal roles for mTORC2 in promoting thymic T cell development and T-ALL and indicate that mTORC2 is crucial for Notch signaling to regulate Akt and NF-κB.
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Abstract
Immunoglobulin superfamily member 4 (IGSF4) is a known ligand of CRTAM, a receptor expressed in activated NKT and CD8(+) T cells, but its function in T cell immunity has not been elucidated. In this study, we show that IGSF4 directly interacts with the T cell receptor (TCR) ζ-chain and enhances TCR signaling by enhancing ζ-chain phosphorylation. Ectopic overexpression of IGSF4 enhances TCR-mediated T cell activation. In contrast, IGSF4 knockdown shows a dramatic decrease in markers associated with T cell activation compared with those in control small interfering RNA. The transmembrane domain is essential for TCR ζ-chain association and clustering to the immunological synapse, and the ectodomain is associated with T cell interaction with antigen-presenting cells (APCs). IGSF4-deficient mice have impaired TCR-mediated thymocyte selection and maturation. Furthermore, these mice reveal attenuated effector T cell functions accompanied by defective TCR signaling. Collectively, the results indicate that IGSF4 plays a central role in T cell functioning by dual independent mechanisms, control of TCR signaling and control of T cell-APC interaction.
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Levels of circulating IL-33 and eosinophil cationic protein in patients with hypereosinophilia or pulmonary eosinophilia. J Allergy Clin Immunol 2010; 126:880-882.e6. [PMID: 20719375 DOI: 10.1016/j.jaci.2010.06.038] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2010] [Revised: 06/23/2010] [Accepted: 06/28/2010] [Indexed: 10/19/2022]
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Loss of the Parkinson's disease-linked gene DJ-1 perturbs mitochondrial dynamics. Hum Mol Genet 2010; 19:3734-46. [PMID: 20639397 DOI: 10.1093/hmg/ddq288] [Citation(s) in RCA: 286] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Growing evidence highlights a role for mitochondrial dysfunction and oxidative stress as underlying contributors to Parkinson's disease (PD) pathogenesis. DJ-1 (PARK7) is a recently identified recessive familial PD gene. Its loss leads to increased susceptibility of neurons to oxidative stress and death. However, its mechanism of action is not fully understood. Presently, we report that DJ-1 deficiency in cell lines, cultured neurons, mouse brain and lymphoblast cells derived from DJ-1 patients display aberrant mitochondrial morphology. We also show that these DJ-1-dependent mitochondrial defects contribute to oxidative stress-induced sensitivity to cell death since reversal of this fragmented mitochondrial phenotype abrogates neuronal cell death. Reactive oxygen species (ROS) appear to play a critical role in the observed defects, as ROS scavengers rescue the phenotype and mitochondria isolated from DJ-1 deficient animals produce more ROS compared with control. Importantly, the aberrant mitochondrial phenotype can be rescued by the expression of Pink1 and Parkin, two PD-linked genes involved in regulating mitochondrial dynamics and quality control. Finally, we show that DJ-1 deficiency leads to altered autophagy in murine and human cells. Our findings define a mechanism by which the DJ-1-dependent mitochondrial defects contribute to the increased sensitivity to oxidative stress-induced cell death that has been previously reported.
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Apoptotic induction by simvastatin in human lung cancer A549 cells via Akt signaling dependent down-regulation of survivin. Invest New Drugs 2010; 29:945-52. [PMID: 20464445 DOI: 10.1007/s10637-010-9450-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Accepted: 05/02/2010] [Indexed: 02/06/2023]
Abstract
Statins, HMG-CoA reductase inhibitors have been studied for their antiproliferative and proapototic effects. Recently, statin-induced apoptosis has been associated with down-regulation of survivin expression in cancer cells. However, the mechanism of deregulated survivin by simvastatin on lung cancer is still unclear. Herein, we demonstrated that simvastatin induced caspase-dependent apoptosis in A549 lung cancer cells. Simvastatin also resulted in a decrease in the expression of phosphorylated Akt. In addition, simvastatin effectively down-regulated survivin mRNA and protein, but not cIAP-1 and cIAP-2. The combination of simvastatin and 10 μM LY294002 (non-toxic dose) augmented apoptosis significantly, as evidenced by cleavage of PARP. The immunoreactive band of survivin was markedly decreased in cells treated with 50 μM LY294002 (toxic dose) as well as by the combination of simvastatin and 10 μM LY294002. Moreover, survivin down-regulation by RNA interference induced apoptosis accompanied by an increase in hypodiploid DNA content. Taken together, these data suggest that the anti-cancer effect of simvastatin via induction of apoptosis is related to Akt signaling dependent down-regulation of survivin in lung cancer A549 cells.
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Evaluation of Analytical Measurement Ranges of Three Full Range C-Reactive Protein Tests Using Immunoturbidimetric Assay. Ann Lab Med 2010; 30:9-16. [DOI: 10.3343/kjlm.2010.30.1.9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Relationship between the Echocardiographic Epicardial Adipose Tissue Thickness and Serum Adiponectin in Patients with Angina. J Cardiovasc Ultrasound 2009; 17:121-6. [PMID: 20661336 DOI: 10.4250/jcu.2009.17.4.121] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2009] [Revised: 11/02/2009] [Accepted: 11/30/2009] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND It is still unknown whether increased cardiac adiposity is related to the risk factors of coronary artery disease (CAD). We measured epicaridal adopose tissue (EAT) and mediastinal adipose tissue (MAT) using echocardiography and examined their correlations with CAD and serum adiponectin. METHODS One hundred fifty three patients who underwent elective coronary angiography for chest pain were measured cardiac adiposity by transthoracic echocardiography. The correlations of cardiac adipose tissue with the presence and severity of CAD and the serum adiponectin level were examined. RESULTS EAT was thicker in patients with CAD (1.8+/-1.4 vs. 3.8+/-1.9 mm, p<0.001), but MAT was not different according to the presence of CAD (2.9+/-2.8 vs. 3.5+/-2.5 mm, p=0.121). EAT showed a significant positive correlation with age (r=0.225, p=0.005), homocystein (r=0.289, p=0.001), fasting glucose (r=0.167, p=0.042), and fibrinogen (r=0.218, p=0.009), and a significant negative correlation with serum adiponectin (r=-0.194, p=0.016). EAT thickness (OR 11.53, 95% CI; 3.61-36.84, p<0.001) and low serum adiponectin (OR 2.88, 95% CI; 1.02-8.15, p=0.046) were independent predictors of obstructive CAD. However, MAT thickness was not associated with CAD. CONCLUSION EAT was associated with the severity and risk factors of CAD and correlated with serum adiponectin level. In contrast with EAT, MAT was not associated with CAD and adiponectin.
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Clinical course of monoclonal and oligoclonal gammopathies in patients infected with Orientia tsutsugamushi. Am J Trop Med Hyg 2009; 81:660-4. [PMID: 19815883 DOI: 10.4269/ajtmh.2009.09-0063] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Although we have encountered many cases of monoclonal gammopathies (MGs) or oligoclonal gammopathies (OGs) in patients with Orientia tsutsugamushi infections, the clinical course of MG/OG associated with these infections has rarely been reported. We serially monitored 18 cases of MG/OG that appeared in the acute phase or early convalescent phase of scrub typhus. All MGs/OGs associated with infection with O. tsutsugamushi disappeared 7-15 weeks after treatment with doxycycline. In three cases of scrub typhus, MGs/OGs appeared before seropositive conversion (presence of antibodies against O. tsutsugamushi) and disappeared before seronegative conversion. Understanding our cases may be helpful for relevant clinical counseling and making appropriate medical decisions to avoid unnecessary invasive or cost-intensive diagnostic procedures for MGs/OGs in scrub typhus, especially in disease-endemic areas. We also suggest that 2-4 months after antibiotic treatment might be the optimal follow-up time to observe the disappearance of MGs/OGs associated with O. tsutsugamushi infections.
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Levels of Soluble Receptor for Advanced Glycation End Products in Acute Ischemic Stroke without a Source of Cardioembolism. J Clin Neurol 2009; 5:126-32. [PMID: 19826563 PMCID: PMC2760717 DOI: 10.3988/jcn.2009.5.3.126] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2009] [Revised: 06/05/2009] [Accepted: 06/05/2009] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND AND PURPOSE Low levels of soluble receptor for advanced glycation end products (sRAGE) are associated with three conventional vascular risk factors (3Fs: diabetes, hypertension, and hypercholesterolemia), nondiabetic coronary artery disease, and Alzheimer's disease. However, the association between sRAGE and acute ischemic stroke (AS), especially AS without a source of cardioembolism, has not yet been established. METHODS Patients with AS without a source of cardioembolism (n=259) and age-matched controls (n=300) were grouped according to the presence of 3Fs: AS patients with and without 3Fs (3Fs+ AS and 3Fs- AS, respectively) and controls with and without 3Fs (3Fs+ control and 3Fs- control, respectively). Levels of sRAGE were analyzed among the four groups. RESULTS sRAGE was significantly higher in the controls than in the AS patients (855 pg/mL vs. 690 pg/mL, p<0.01). sRAGE was significantly higher in 3Fs- controls (996 pg/mL, p<0.05) than in 3Fs+ controls (721 pg/mL), and in AS group regardless of the 3Fs (629 pg/mL in 3Fs- and 705 pg/mL in 3Fs+). The lowest tertile of sRAGE was associated with an increased risk of AS in the 3Fs- group [adjusted odds ratio (OR) 4.0, 95% confidence interval (CI) 1.6-10.3, p<0.01] but not in the 3Fs+ group. The level of sRAGE was also correlated with neurological severity in the 3Fs- AS group (r=-0.32, p<0.05) but not in the 3Fs+ AS group. CONCLUSIONS Low plasma levels of sRAGE is a potential biomarker for the risk of AS and may reflect the neurological severity of the condition, especially in subjects without identifiable conventional risk factors.
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Simvastatin treatment induces morphology alterations and apoptosis in murine cochlear neuronal cells. Acta Otolaryngol 2009; 129:166-74. [PMID: 18607908 DOI: 10.1080/00016480802163358] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
CONCLUSION Simvastatin presented neurodegenerative morphological changes and cell death via its specific inhibition of mevalonate pathway induced apoptosis in cultured cochlear neuronal cells. These findings might contribute to understanding the auditory neurobiological effects of HMG-CoA reductase inhibitors. OBJECTIVES The statins are 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors that are widely used as anti-hypercholesterol drugs because of their beneficial cardiovascular effects. However, the effects of statins in neuronal cells are controversial, and no studies have examined the effect of statins in cochlear neuronal cells. The objective of this study was to evaluate the direct effect of simvastatin on cochlear neuronal cells and examine the mechanisms underlying these effects. MATERIALS AND METHODS Cultured mouse cochlear neuroblasts (VOT-33) and primary rat cochlear explants containing spiral ganglion neurons were treated with simvastatin in the absence or presence of mevalonate. RESULTS Simvastatin caused a loss of the cytoplasmic projections in VOT-33. In primary rat cochlear nerve cells, simvastatin decreased staining for NF200, a neuro-cytoskeletal protein. We also found that simvastatin-induced VOT-33 apoptosis, as indicated by accumulation of the sub G0/G1 fraction, DNA-ladder formation, and caspase-3 activation. The above-mentioned effects were abolished by mevalonate treatment.
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Distribution of hepatitis B virus genotypes in Korea. THE KOREAN JOURNAL OF HEPATOLOGY 2009; 15:140-7. [DOI: 10.3350/kjhep.2009.15.2.140] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Correlation Between Insulin Resistance and Intracranial Atherosclerosis in Patients With Ischemic Stroke Without Diabetes. J Stroke Cerebrovasc Dis 2008; 17:401-5. [DOI: 10.1016/j.jstrokecerebrovasdis.2008.06.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2008] [Revised: 05/28/2008] [Accepted: 06/09/2008] [Indexed: 11/24/2022] Open
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WITHDRAWN: Prognostic factors of biochemical recurrence after radical prostatectomy in Korean men with high-risk prostate cancer. EUROPEAN JOURNAL OF SURGICAL ONCOLOGY 2007:S0748-7983(07)00550-1. [PMID: 17983725 DOI: 10.1016/j.ejso.2007.09.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2007] [Accepted: 09/25/2007] [Indexed: 10/22/2022]
Abstract
This article has been withdrawn consistent with Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The Publisher apologizes for any inconvenience this may cause.
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Clinical Significance of Serum Interleukin-18 Concentration in the Patients with Atopic Dermatitis. Ann Lab Med 2007; 27:128-32. [DOI: 10.3343/kjlm.2007.27.2.128] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Cell cycle machinery and stroke. Biochim Biophys Acta Mol Basis Dis 2007; 1772:484-93. [PMID: 17241774 DOI: 10.1016/j.bbadis.2006.11.009] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2006] [Revised: 11/22/2006] [Accepted: 11/29/2006] [Indexed: 11/30/2022]
Abstract
Stroke results from a transient or permanent reduction in blood flow to the brain. The mechanisms involving neuronal death following ischemic insult are complex and not fully understood. One signal which may control ischemic neuronal death is the inappropriate activation of cell cycle regulators including cyclins, cyclin dependent kinases (CDKs) and endogenous cyclin dependent kinase inhibitors (CDKIs). In dividing cells, activation of cell cycle machinery induces cell proliferation. In the context of terminally differentiated-neurons, however, aberrant activation of these elements triggers neuronal death. Indeed, there are several lines of correlative and functional evidence supporting this "cell cycle/neuronal death hypothesis". The objective of this review is to summarize the findings implicating cell cycle machinery in ischemic neuronal death from in vitro and in vivo studies. Importantly, determining and blocking the signaling pathway(s) by which these molecules act to mediate ischemic neuronal death, in conjunction with other targets may provide a viable therapeutic strategy for stroke damage.
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Iron chelator induces THP-1 cell differentiation potentially by modulating intracellular glutathione levels. Free Radic Biol Med 2006; 40:1502-12. [PMID: 16632111 DOI: 10.1016/j.freeradbiomed.2005.12.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2005] [Revised: 11/12/2005] [Accepted: 12/19/2005] [Indexed: 11/21/2022]
Abstract
Iron chelators have been implicated to modulate certain inflammatory mediators and regulate inflammatory processes. Here we report that iron chelator deferoxamine (DFO) induces differentiation of monocytic THP-1 cells into functional macrophages. DFO rapidly phosphorylated both extracellular signal-regulated kinase (ERK) and p38 kinase. Blockade of ERK signaling by the MEK1/2 inhibitor PD098059 abolished DFO-induced class A scavenger receptor (SR-A) expression and phagocytic activity, indicating that ERK cascades mediate the induction of THP-1 differentiation. In contrast, in cells treated with the p38 inhibitor SB203580 or transfected with the dominant-negative variant of p38 kinase, DFO-mediated ERK activation became more prominent, and the induction of SR-A expression and phagocytic activity were significantly increased. Interestingly, differentiation by DFO was associated with decrease in cellular glutathione (GSH) level. Both MAPK inhibitors did not influence the GSH level; however, treatment with ferric citrate (Fe3+) or N-acetyl-cysteine, a major precursor of GSH, markedly recovered GSH level to a normal extent, along with the significant decrease of differentiation. Collectively, these results indicate that oxidative stress by DFO and the resulting activation of ERK cascade play dominant roles in the process of THP-1 differentiation, while p38 acts as a negative signal transmitter.
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Sequence motifs in IL-4R alpha mediating cell-cycle progression of primary lymphocytes. THE JOURNAL OF IMMUNOLOGY 2005; 175:5178-85. [PMID: 16210622 DOI: 10.4049/jimmunol.175.8.5178] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
IL-4 signaling through the IL-4Ralpha chain regulates the development and proliferation of the Th2 lineage of effector CD4(+) T cells. Analyses of the IL-4R in factor-dependent cell lines led to the development of two apparently conflicting models of the primary structural determinants of IL-4R-mediated proliferative signaling. In one model, proliferation was dependent on the first conserved tyrosine in the cytoplasmic tail (Y1), while in the second, proliferation was independent of cytoplasmic tyrosines. We found that in activated primary T cells, mutation of only the Y1 residue resulted in a modest decrease in IL-4-induced S phase entry, a further decrease in cell-cycle completion, and a complete failure of IL-4 to induce p70S6 kinase phosphorylation. Consistent with a role for the PI3K/mammalian target of rapamycin pathway in mediating cytokine acceleration of G(2)/M transit, pretreatment of activated T cells with rapamycin resulted in only a modest decrease in IL-4-induced S phase entry, but a total block of cell-cycle completion. Strikingly, IL-4Ralpha chains that lacked all cytoplasmic tyrosines were competent to signal for STAT5 phosphorylation, mediated efficient S phase entry, and promoted cell-cycle progression. The ability of tyrosine-deficient IL-4Rs to mediate proliferative signaling and STAT phosphorylation was absolutely dependent on the presence of an intact ID-1 region. These findings show that IL-4Ralpha lacking cytoplasmic tyrosine residues is competent to induce ID-1-dependent proliferation, and indicate that IL-4 can promote G(2)/M progression via activation of the mammalian target of rapamycin pathway initiated at the Y1 residue.
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Surgical Outcome of Endoscopic Carpal Tunnel Release in 100 Patients with Carpal Tunnel Syndrome. ACTA ACUST UNITED AC 2004; 47:261-5. [PMID: 15578337 DOI: 10.1055/s-2004-830075] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The purpose of this study is to present the surgical outcome of endoscopic carpal tunnel release (ECTR) for the treatment of carpal tunnel syndrome (CTS). One hundred and thirty-one procedures (36 right hands, 33 left hands and 31 bilateral hands) of single portal ECTR were performed upon 100 patients (age range: 36-77 years, mean age: 52.9 years; 98 women and 2 men) with electrodiagnostically proven CTS for 2.5 years from 2001. Preoperative clinical severity and results of electrodiagnostic studies were compared with surgical outcomes at the minimal 3-month postoperative period. Among 131 cases 125 (95.4 %) with complete or significant relief of symptoms were satisfied and 6 (4.6 %) with partial or no relief of symptoms were dissatisfied. There were 2 cases of major complications (one with ulnar nerve injury and the other with ulnar artery injury) that developed in our early experience of ECTR and 1 case of recurrence. The grade of electrodiagnostic abnormalities was associated with surgical outcome but there was no statistical significance between them. The severity of clinical findings, age at onset and symptom duration were not correlated with surgical outcome. In conclusion, ECTR surgery was effective in relieving the symptoms of CTS with a low complication rate after the learning curve period. Thus, ECTR can be an alternative to the traditional open surgery and can be the first procedure for CTS with several advantages over open methods.
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Catalposide, a compound isolated from catalpa ovata, attenuates induction of intestinal epithelial proinflammatory gene expression and reduces the severity of trinitrobenzene sulfonic Acid-induced colitis in mice. Inflamm Bowel Dis 2004; 10:564-72. [PMID: 15472516 DOI: 10.1097/00054725-200409000-00010] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Certain irinoid-producing plants have been used as herbal anti-inflammatory remedies. Here we evaluated whether catalposide (CATP), a single compound isolated from irinoid-producing plant Catalpa ovata, has a potential for preventing or ameliorating diseases characterized by mucosal inflammation. Preliminary microarray-based gene expression test revealed that CATP, which alone did not significantly affect expression of any of the >8,000 genes analyzed, attenuated the expression of tumor necrosis factor-alpha (TNF-alpha)-induced proinflammatory genes including interleukin-8 (IL-8) in human intestinal epithelial HT-29 cells. Down-regulation of IL-8 mRNA accumulation was also reflected by the decreased IL-8 secretion in CATP-treated HT-29 cells. The signal transduction study revealed that CATP significantly attenuates TNF-alpha-mediated p38 and extracellular signal-regulated kinase (ERK) phosphorylation. Further, CATP reduced NF-kappaB-mediated transcriptional activation as well as Ikappa-Balpha degradation. To establish the in vivo relevance of these findings, we examined whether CATP could affect intestinal inflammation in vivo using the mouse model of trinitrobenzene sulfonic acid (TNBS)-induced inflammatory colitis. Intrarectal administration of CATP dramatically reduced the weight loss, colonic damage, and mucosal ulceration that characterize TNBS colitis. Moreover, CATP suppressed the expression of TNF-alpha, interleukin-1beta, and intercellular adhesion molecule-1 along with the inhibition of NF-kappa B p65 translocation into nucleus in TNBS colitis. Collectively, current results demonstrate that CATP may be an effective agent for the treatment of diseases characterized by mucosal inflammation.
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C-shaped root canals of mandibular second molars in a Korean population: clinical observation andin vitroanalysis. Int Endod J 2004; 37:139-44. [PMID: 14871181 DOI: 10.1111/j.0143-2885.2004.00772.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIM To investigate the incidence and morphology of C-shaped root canals of the mandibular second molar in a Korean population. METHODOLOGY Through clinical observation, randomly selected 272 mandibular second molars of Korean patients were accessed and evaluated after taking radiographs for determination of working length. In an in vitro analysis, 96 extracted mandibular second molars of Korean patients were collected and embedded in resin using an Endodontic cube technique, and were sectioned at intervals of 1 mm. The specimens were then observed with a surgical microscope and were photographed. Canal configurations were assigned to one of three categories: Category I defined a C-shaped outline without any separation; Category II referred to those with canal configurations, where dentine separated one distinct canal from a buccal or lingual C-shaped canal; Category III had two or more discrete and separate canals. RESULTS In clinical observation, 89 of 272 teeth (32.7%) had C-shaped canals. Of the 96 teeth examined in vitro, 30 (31.3%) had C-shaped canals. Upon in vitro analysis, only 1 tooth at the subpulpal level and 10 teeth at the apical 1 mm level were categorized under Category III. CONCLUSION There was high prevalence of C-shaped root canals in the mandibular second molars of Koreans. C-shaped canals having semicolon and continuous shapes at the canal orifice have a high possibility of being divided into two or three canals in the apical region.
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Attenuation of MPTP-induced neurotoxicity and behavioural impairment in NSE-XIAP transgenic mice. Neurobiol Dis 2003; 12:150-61. [PMID: 12667469 DOI: 10.1016/s0969-9961(02)00020-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
X-linked IAP protein is a potent inhibitor of cell death. Here, we describe a novel transgenic mouse in which the human XIAP gene is expressed under the control of the neuron-specific enolase promoter (NSE-xiap). We demonstrate that nigrostriatal dopamine neurons of NSE-xiap mice were resistant to the damaging effects of the dopaminergic neurotoxin MPTP. MPTP-induced reduction of striatal dopamine metabolism was also attenuated in NSE-xiap mice. Furthermore, NSE-xiap mice treated with MPTP did not exhibit deficits in exploratory behaviour in an open-field test. Taken together, these findings suggest that strategies to enhance neuronal expression of XIAP may provide therapeutic benefit for the treatment of neurodegeneration in Parkinson's disease.
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Inhibitors of trypsin-like serine proteases prevent DNA damage-induced neuronal death by acting upstream of the mitochondrial checkpoint and of p53 induction. Neuroscience 2002; 107:339-52. [PMID: 11731108 DOI: 10.1016/s0306-4522(01)00322-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
We have previously shown that the pharmacological agents 4-(2-aminoethyl)=benzenesulfonylfluoride hydrochloride (AEBSF) and Na-p-tosyl-L-lysine chloromethylketone (TLCK), inhibitors of trypsin-like serine proteases, prevent the death of trophic factor-deprived PC12 cells and sympathetic neurons. Both AEBSF and TLCK inhibit caspase activation in this model, but it is unclear whether they do so indirectly or through a direct effect at the level of the caspases. In the current study, we have used these agents in another model of neuronal death that is induced by DNA damage. We find that both agents delay the death of DNA-damaged PC12 cells, neonatal rat sympathetic neurons and embryonic rat cortical neurons. As in the trophic deprivation model, they act upstream of the caspases. In addition, they prevent mitochondrial alterations, such as cytochrome c release or loss of transmembrane potential. In contrast, the general caspase inhibitor bok-asp-fmk does not prevent cytochrome c release and has only a partial and transient effect on loss of transmembrane potential. Interestingly, both AEBSF and TLCK prevent the induction and nuclear accumulation of p53 that is induced by DNA damage in cortical neurons. Therefore, these serine protease inhibitors act at a point upstream in the apoptotic pathway, prior to p53 induction and the mitochondrial checkpoint, to delay neuronal death in this model, and do not act at the level of the caspases. We conclude that therapeutic strategies based on serine protease inhibition may be useful in preventing neuronal cell death.
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Caveolae-deficient endothelial cells show defects in the uptake and transport of albumin in vivo. J Biol Chem 2001; 276:48619-22. [PMID: 11689550 DOI: 10.1074/jbc.c100613200] [Citation(s) in RCA: 251] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The role of endothelial cell caveolae in the uptake and transport of macromolecules from the blood-space to the tissue-space remains controversial. To address this issue directly, we employed caveolin-1 gene knock-out mice that lack caveolin-1 protein expression and caveolae organelles. Here, we show that endothelial cell caveolae are required for the efficient uptake and transport of a known caveolar ligand, i.e. albumin, in vivo. Caveolin-1-null mice were perfused with 5-nm gold-conjugated albumin, and its uptake was followed by transmission electron microscopy. Our results indicate that gold-conjugated albumin is not endocytosed by Cav-1-deficient lung endothelial cells and remains in the blood vessel lumen; in contrast, gold-conjugated albumin was concentrated and internalized by lung endothelial cell caveolae in wild-type mice, as expected. To quantitate this defect in uptake, we next studied the endocytosis of radioiodinated albumin using aortic ring segments from wild-type and Cav-1-null mice. Interestingly, little or no uptake of radioiodinated albumin was observed in the aortic segments from Cav-1-deficient mice, whereas aortic segments from wild-type mice showed robust uptake that was time- and temperature-dependent and competed by unlabeled albumin. We conclude that endothelial cell caveolae are required for the efficient uptake and transport of albumin from the blood to the interstitium.
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Prolactin negatively regulates caveolin-1 gene expression in the mammary gland during lactation, via a Ras-dependent mechanism. J Biol Chem 2001; 276:48389-97. [PMID: 11602600 DOI: 10.1074/jbc.m108210200] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Caveolin-1 is a 22-kDa integral membrane protein that has been suggested to function as a negative regulator of mitogen-stimulated proliferation in a variety of cell types, including mammary epithelial cells. Because much of our insight into caveolin-1 function has come from the study of human breast tumor-derived cell lines in culture, the normal physiological regulators of caveolin-1 expression in the mammary gland remain unknown. Here, we examine caveolin-1 expression in mice at different stages of mammary gland development. We show that caveolin-1 expression is significantly down-regulated during late pregnancy and lactation. Upon weaning, mammary gland expression of caveolin-1 rapidly returns to non-pregnant "steady-state" levels. Injection of virgin mice with a battery of hormones normally up-regulated during lactation demonstrates that prolactin is the main mediator of caveolin-1 down-regulation. Virtually identical results were obtained with human mammary epithelial cells (hTERT-HME1) in culture. In addition, we demonstrate that prolactin-mediated down-regulation of caveolin-1 expression occurs at the level of transcriptional control and via a Ras-dependent mechanism. Interestingly, in the mammary gland, both mammary epithelial cells and the surrounding mammary adipocytes show prolactin-mediated down-regulation of caveolin-1. This hormone-dependent regulation of caveolin-1 expression is specific to the mammary fat pad. Finally, we employed HC11 cells, a well-established model of mammary epithelial cell differentiation, to study the possible functional effects of caveolin-1 expression. In the presence of lactogenic hormones, recombinant expression of caveolin-1 in HC11 cells dramatically suppresses the induction of the promoter activity and the synthesis of beta-casein, an established reporter of lactogenic differentiation and milk production. These findings may explain why caveolin-1 levels are normally down-regulated during lactation. This report is the first demonstration that caveolin-1 levels are down-regulated during a normal physiological event in vivo, i.e. lactation, because previous reports have only documented that down-regulation of caveolin-1 occurs during cell transformation and tumorigenesis.
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