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101.
Ok-Seon Kwon Ensel Oh Jeong-Rak Park Ji-Seon Lee Gab-Yong Bae Jae-Hyung Koo Hyongbum Kim Yoon-La Choi Young Soo Choi Jhingook Kim Hyuk-Jin Cha 《Oncotarget》2015,6(39):41916-41928
While metastasis, the main cause of lung cancer-related death, has been extensively studied, the underlying molecular mechanism remains unclear. A previous clinicogenomic study revealed that expression of N-acetylgalactosaminyltransferase (GalNAc-T14), is highly inversely correlated with recurrence-free survival in those with non-small cell lung cancer (NSCLC). However, the underlying molecular mechanism(s) has not been determined. Here, we showed that GalNAc-T14 expression was positively associated with the invasive phenotype. Microarray and biochemical analyses revealed that HOXB9, the expression of which was increased in a GalNAc-T14-dependent manner, played an important role in metastasis. GalNAc-T14 increased the sensitivity of the WNT response and increased the stability of the β-catenin protein, leading to induced expression of HOXB9 and acquisition of an invasive phenotype. Pharmacological inhibition of β-catenin in GalNAc-T14-expressing cancer cells suppressed HOXB9 expression and invasion. A meta-analysis of clinical genomics data revealed that expression of GalNAc-T14 or HOXB9 was strongly correlated with reduced recurrence-free survival and increased hazard risk, suggesting that targeting β-catenin within the GalNAc-T14/WNT/HOXB9 axis may be a novel therapeutic approach to inhibit metastasis in NSCLC. 相似文献
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Yong Seong Kim Hyun Won Seo Myon-Hee Lee Dae Keun Kim Hoon Jeon Dong Seok Cha 《Archives of pharmacal research》2014,37(2):245-252
Veronica peregrina has a wide range of types of constituents with various pharmacological properties. Here in this study, we isolated protocatechuic acid (PCA) from V. peregrina and examined PCAs effects on the lifespan and stress tolerance using Caenorhabditis elegans model system. We found that lifespan of wild-type worms was significantly lengthened in the presence of PCA in a dose dependent manner. PCA also elevated tolerance of worms against osmotic, heat shock, and oxidative stress. We also demonstrated antioxidant capacity of PCA by checking intracellular reactive oxygen species level and antioxidant enzyme activities such as catalase and superoxide dismutase. We further investigated several factors including pharyngeal pumping rate and progeny production that might influence prolonged lifespan and enhanced stress tolerance by PCA. Interestingly, both factors were significantly reduced after PCA exposure, indicating PCA exerts longevity activity by shifting food intake and reproduction at least in part. In addition, PCA-treated aged worms showed increased body movement compared to untreated controls suggesting PCA could enhance healthspan as well as lifespan. 相似文献
105.
Seok Jeong Lee Yong Sung Cha Yoonsuk Lee Hyun Kim 《The American journal of emergency medicine》2018,36(9):1718.e1-1718.e3
The risk of thromboembolism is higher in those with carbon monoxide (CO) poisoning than in the general population. Pulmonary embolisms (PE) usually develop during admission for acute CO poisoning. We report the first case of a life-threatening PE that occurred immediately after acute CO poisoning and was treated with a thrombolytic agent. A 38-year-old woman presented at the emergency department with a stuporous mental status immediately after acute CO poisoning. She was started on hyperbaric oxygen therapy (HBOT), which maintained her hemodynamic stability. After completing the first HBOT session, profound shock occurred. The results of focused cardiac ultrasound performed by an emergency physician were completely different from those of the ultrasound conducted before HBOT; hyperdynamic left ventricle systolic function and right ventricle enlargement with dysfunction were detected. We administered a thrombolytic agent as she was suspected with acute PE based on ultrasound findings; computed tomography could not be performed because of impending arrest. She recovered after the treatment. We should consider that PE is also an important differential cause in patients with hypotension. In these patients, bedside ultrasound performed by emergency physicians can act as the only diagnostic examination. 相似文献
106.
Ajay K. Parsaik Maria I. Lapid Teresa A. Rummans Ruth H. Cha Bradley F. Boeve Vernon S. Pankratz Eric G. Tangalos Ronald C. Petersen 《Journal of the American Medical Directors Association》2012,13(8):704-707
ObjectivesApoE ε4 is associated with adverse health conditions that negatively impact the quality of life (QOL). The relationship between ApoE ε4 and QOL has not been explored in the oldest old. Our study aimed to examine ApoE in the oldest old and explore its association with QOL.DesignCross-sectional cohort study.SettingA medium sized community in Olmsted County, Minnesota.ParticipantsIndividuals aged 90 to 99 years, living independently or in long term care environments.MeasurementsWe collected demographic information and measured cognitive function (Short Test of Mental Status, Mini-Mental State Examination, Mattis Dementia Rating Scale), QOL (Linear Analogue Self Assessment), and ApoE distribution. Subjects were classified as cognitively normal, mild cognitive impairment, dementia, or dementia with stroke and/or parkinsonism (DEMSP). Regression model was used to assess the predictors of QOL.ResultsA total of 121 subjects (45 cognitively normal, 13 with mild cognitive impairment, 34 with dementia, 29 DEMSP) aged 90–99 years, 106 (87.6 %) females, were included. Frequency of ApoE ε3 allele was highest (194 [80.2%]: ε2/3 18, ε3/3 77, ε3/4 22) followed by ApoE ε4 (25 [10.3%]: ε2/4 3, ε3/4 22) and ApoE ε2 (23 [9.5%; ε2/2 1, ε2/3 18, ε2/4 3). None of the subjects carried ApoE ε4/4 genotype. QOL was similar between ApoE ε4 carrier and noncarriers. Physical well-being, emotional well-being, intellectual well-being, social connectedness, and coping ability were positively associated with QOL, whereas male sex, DEMSP, pain frequency, and pain severity were negatively associated.ConclusionsThe most common ApoE in the oldest old was ε3/3 genotype and ε3 allele. No association was found between ApoE ε4 and QOL. However, those with high physical, emotional and intellectual well being, social connectedness, and coping ability had the highest overall QOL. 相似文献
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Anthony J. Bonito Costica Aloman M. Isabel Fiel Nichole M. Danzl Sungwon Cha Erica G. Weinstein Seihwan Jeong Yongwon Choi Matthew C. Walsh Konstantina Alexandropoulos 《The Journal of clinical investigation》2013,123(8):3510-3524
TRAF6, an E3 ubiquitin protein ligase, plays a critical role in T cell tolerance by regulating medullary thymic epithelial cell (mTEC) development. mTECs regulate T cell tolerance by ectopically expressing self-antigens and eliminating autoreactive T cells in the thymus. Here we show that mice with mTEC depletion due to conditional deletion of Traf6 expression in murine thymic epithelial cells (Traf6ΔTEC mice) showed a surprisingly narrow spectrum of autoimmunity affecting the liver. The liver inflammation in Traf6ΔTEC mice exhibited all the histological and immunological characteristics of human autoimmune hepatitis (AIH). The role of T cells in AIH establishment was supported by intrahepatic T cell population changes and AIH development after transfer of liver T cells into immunodeficient mice. Despite a 50% reduction in natural Treg thymic output, peripheral tolerance in Traf6ΔTEC mice was normal, whereas compensatory T regulatory mechanisms were evident in the liver of these animals. These data indicate that mTECs exert a cell-autonomous role in central T cell tolerance and organ-specific autoimmunity, but play a redundant role in peripheral tolerance. These findings also demonstrate that Traf6ΔTEC mice are a relevant model with which to study the pathophysiology of AIH, as well as autoantigen-specific T cell responses and regulatory mechanisms underlying this disease. 相似文献
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