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Neuroinflammation in neurodegenerative disorders:the roles of microglia and astrocytes 被引量:82
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作者 Hyuk Sung kwon Seong-Ho Koh 《Translational Neurodegeneration》 SCIE CAS 2020年第4期535-546,共12页
Neuroinflammation is associated with neurodegenerative diseases,such as Alzheimer's disease,Parkinson's disease,ancamyotrophic lateral sclerosis.Microglia and astrocytes are key regulators of inflammatory resp... Neuroinflammation is associated with neurodegenerative diseases,such as Alzheimer's disease,Parkinson's disease,ancamyotrophic lateral sclerosis.Microglia and astrocytes are key regulators of inflammatory responses in the central nervous system.The activation of microglia and astrocytes is heterogeneous and traditionally categorized as neurotoxi(M1-phenotype microglia and A1-phenotype astrocytes)or neuroprotective(M2-phenotype microglia and A2-phenotype astrocytes).However,this dichotomized classification may not reflect the various phenotypes of microgliaand astrocytes.The relationship between these activated glial cells is also very complicated,and the phenotypic distribution can change,based on the progression of neurodegenerative diseases.A better understanding of the rolesof microglia and astrocytes in neurodegenerative diseases is essential for developing effective therapies.In this review,we discuss the roles of inflammatory response in neurodegenerative diseases,focusing on the contributions of microglia and astrocytes and their relationship.In addition,we discuss biomarkers to measure neuroinflammation andstudies on therapeutic drugs that can modulate neuroinflammation. 展开更多
关键词 NEUROINFLAMMATION Neurodegenerative diseases MICROGLIA ASTROCYTES
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Natural Variation in OsPRR37 Regulates Heading Date and Contributes to Rice Cultivation at a Wide Range of Latitudes 被引量:48
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作者 Bon-Hyuk Koo Soo-Cheul Yoo +7 位作者 Joon-Woo Park Choon-Tak kwon Byoung-Doo Lee Gynheung An Zhanying Zhang linjie Li Zichao Li Nam-Chon Paek 《Molecular Plant》 SCIE CAS CSCD 2013年第6期1877-1888,共12页
Heading date and photoperiod sensitivity are fundamental traits that determine rice adaptation to a wide range of geographic environments. By quantitative trait locus (QTL) mapping and candidate gene analysis using ... Heading date and photoperiod sensitivity are fundamental traits that determine rice adaptation to a wide range of geographic environments. By quantitative trait locus (QTL) mapping and candidate gene analysis using whole- genome re-sequencing, we found that Oryza sativa Pseudo-Response Regulator37 (OsPRR37; hereafter PRR37) is respon- sible for the Early heading7-2 (EH7-2)/Heading date2 (Hd2) QTL which was identified from a cross of late-heading rice 'Milyang23 (M23)' and early-heading rice 'H143'. H143 contains a missense mutation of an invariantly conserved amino acid in the CCT (CONSTANS, CO-like, and TOC1) domain of PRR37 protein. In the world rice collection, different types of nonfunctional PRR37 alleles were found in many European and Asian rice cultivars. Notably, the japonica varieties harboring nonfunctional alleles of both Ghd7/Hd4 and PRR37/Hd2 flower extremely early under natural long-day condi- tions, and are adapted to the northernmost regions of rice cultivation, up to 53~ N latitude. Genetic analysis revealed that the effects of PRR37 and Ghd7 alleles on heading date are additive, and PRR37 down-regulates Hd3a expression to suppress flowering under long-day conditions. Our results demonstrate that natural variations in PRR37/Hd2 and GhdT/ Hd4 have contributed to the expansion of rice cultivation to temperate and cooler regions. 展开更多
关键词 RICE heading date quantitative trait locus natural variation Ghd7 OsPRR37.
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Effects of Momentum Ratio and Weber Number on Spray Half Angles of Liquid Controlled Pintle Injector 被引量:27
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作者 Min Son Kijeong Yu +2 位作者 Jaye Koo Oh Chae kwon Jeong Soo Kim 《Journal of Thermal Science》 SCIE EI CAS CSCD 2015年第1期37-43,共7页
A pintle injector is advantageous for throttling a liquid rocket engine and reducing engine weight. This study ex- plores the effects of momentum ratio and Weber number at various injection conditions on spray charact... A pintle injector is advantageous for throttling a liquid rocket engine and reducing engine weight. This study ex- plores the effects of momentum ratio and Weber number at various injection conditions on spray characteristics of the pintle injector for liquid-gas propellants. A liquid sheet is injected from a center pintle nozzle and it is broken by a gas jet from an annular gap. The pressure drops of propellants, and the pintle opening distance were consi- dered as control variables; using 0.1 -1.0 as a bar for the pressure drop of the liquid injection, a 0.01-4).2 bar for the pressure drop of gas jet and a 0.2 - 1.0 mm for the pintle opening distance. The discharge coefficient was de- creased linearly before the pintle opening distance of 0.75 mm and then, the coefficient was slightly increased. Spray images were captured by a CMOS camera with high resolution. Then, the shadow and reflected images were analyzed. Spray distributions were measured by a pattemator with an axial distance of 50 mm from a pintle tip. Finally, the spray half angles had an exponentially decreasing correlation as a momentum ratio divided by the Weber number. Also, the spray half angles from the spray distribution were underestimated compared to those measured from the captured images. 展开更多
关键词 Pintle Injector Spray Half Angle Spray Distribution VISUALIZATION
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Biogenesis and regulation of the let-7 miRNAs and their functional implications 被引量:26
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作者 Hosuk Lee Sungwook Han +1 位作者 Chang Seob kwon Daeyoup Lee 《Protein & Cell》 SCIE CAS CSCD 2016年第2期100-113,共14页
The let-7 miRNAwas one of the first miRNAs discovered in the nematode, Caenorhabditis elegans, and its biological functions show a high level of evolutionary conservation from the nematode to the human. Unlike in C. e... The let-7 miRNAwas one of the first miRNAs discovered in the nematode, Caenorhabditis elegans, and its biological functions show a high level of evolutionary conservation from the nematode to the human. Unlike in C. elegans, higher animals have multiple isoforms of let-7 miRNAs; these isoforms share a consensus sequence called the 'seed sequence' and these isoforms are categorized into let-7 miRNA family. The expression of let-7 family is required for developmental timing and tumor suppressor function, but must be suppressed for the self-renewal of stem cells. Therefore, let-7 miRNA biogenesis must be carefully controlled. To generate a let-7 miRNA, a primary transcript is produced by RNA polymerase Ⅱ and then subsequently processed by Drosha/DGCR8, TUTase, and Dicer. Because dysregulation of let-7 processing is deleterious, biogenesis of let-7 is tightly regulated by cellular factors, such as the RNA binding proteins, LIN28A/B and DIS3L2. In this review, we discuss the biological functions and biogenesis of let-7 miRNAs, focusing on the molecular mechanisms of regulation of let-7 biogenesis in ver- tebrates, such as the mouse and the human. 展开更多
关键词 miRNA processing miRNA biogenesis let-7 family TUTase LIN28A/B
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Cortex cinnamomi extract prevents streptozotocin- and cytokine-induced β-cell damage by inhibiting NF-κB 被引量:24
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作者 Kang-Beom kwon Eun-Kyung Kim +5 位作者 Eun-Sil Jeong Young-Hoon Lee Young-Rae Lee Jin-Woo Park Do-Gon Ryu Byung-Hyun Park 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第27期4331-4337,共7页
AIM: To clarify the mechanism underlying the antidiabetic activities of cortex cinnamomi extract (CCE). METHODS: To induce in vivo diabetes, mice were injected with streptozotocin (STZ) via a tail vein (100 mg ... AIM: To clarify the mechanism underlying the antidiabetic activities of cortex cinnamomi extract (CCE). METHODS: To induce in vivo diabetes, mice were injected with streptozotocin (STZ) via a tail vein (100 mg STZ/kg body weight). To determine the effects of CCE, mice were administered CCE twice daily for 7 d by oral gavage starting 1 wk before the STZ injection. Blood glucose and plasma insulin concentration were measured as an index of diabetes. Also, to induce cytotoxicity of RINm5F cells, we treated with cytokines (IL-1β (2.0 ng/mL) and IFN-γ (100 U/mL)). Cell viability and nitric oxide production were measured colorimetrically. Inducible nitric oxide synthase (iNOS) mRNA and protein expression were determined by RT-PCR and Western blotting, respectively. The activation of NF-κβ was assayed by using gel mobility shift assays of nuclear extracts. RESULTS: Treatment of mice with STZ resulted in hyperglycemia and hypoinsulinemia, which was further evidenced by immunohistochemical staining of islets. However, the diabetogenic effects of STZ were completely prevented when mice were pretreated with CCE. The inhibitory effect of CCE on STZ-induced hyperglycemia was mediated through the suppression of iNOS expression. In rat insulinoma RINm5F cells,CCE completely protected against interleukin-1β and interferon-y-mediated cytotoxicity. Moreover, RINm5F cells incubated with CCE showed significant reductions in interleukin-1β and interferon-y-induced nitric oxide production and in iNOS mRNA and protein expression, and these findings correlated well with in vivo observations. CONCLUSION: The molecular mechanism by which CCE inhibits iNOS gene expression appears to involve the inhibition of NF-κβ activation, These results reveal the possible therapeutic value of CCE for the prevention of diabetes mellitus progression, 展开更多
关键词 Cortex cinnamomi Diabetes STREPTOZOTOCIN CYTOKINE NF-ΚΒ
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Solid-state bonding between Al and Cu by vacuum hot pressing 被引量:25
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作者 Kwang Seok LEE Yong-Nam kwon 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第2期341-346,共6页
Diffusion bonding between aluminum and copper was performed by vacuum hot pressing at temperatures between 623 and 923 K through two thermal processes: hot compression under the deformation rate of 0.2 mrrdmin for 10... Diffusion bonding between aluminum and copper was performed by vacuum hot pressing at temperatures between 623 and 923 K through two thermal processes: hot compression under the deformation rate of 0.2 mrrdmin for 10 rain at pre-set temperatures, and additional pressing at 0.2 mm/min for 20 rain during furnace cooling. After analyzing interface, the feasible diffusion bonding temperature was suggested as 823 K. The three major intermetallic layers generated during diffusion bonding process were identified as AIECu, AlCu+AlaCu4 and Al4Cu9. Furthermore, local hardness values ofAlECU, AlCu+AlaCu4 and Al4Cu9 layers average at (4.97±0.05), (6.33±0.00) and (6.06±0.18) GPa, respectively. 展开更多
关键词 vacuum hot pressing diffusion bonding Al-Cu intermetallic compound composite interface interface microstructures NANOINDENTATION
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Acoustic radiation force impulse elastography for hepatocellular carcinoma-associated radiofrequency ablation 被引量:21
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作者 Hee-Jin kwon Myong-Jin Kang +4 位作者 Jin-Han Cho Jong-Young Oh Kyung-Jin Nam Sang-Yeong Han Sung Wook Lee 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第14期1874-1878,共5页
AIM:To evaluate the potential usefulness of acoustic radiation force impulse (ARFI) images for evaluation of hepatocellular carcinomas (HCC)-associated radiofrequency ablation. METHODS:From January 2010 to June 2010,a... AIM:To evaluate the potential usefulness of acoustic radiation force impulse (ARFI) images for evaluation of hepatocellular carcinomas (HCC)-associated radiofrequency ablation. METHODS:From January 2010 to June 2010,a total of 38 patients with HCC including recurred HCCs after RFA underwent ARFI elastography. The brightness of tumor was checked and the shear wave velocity was measure-d for the-quantification of stiffne-ss. According to theb-rightne-ss,the-tumors we-re-classifie-d as b-righte-r,samecolor and darker compared with adjacent parenchyma. Using the same methods,8 patients with recurred HCCs after RFA state were evaluated about the brightness compared with adjacent RFA ablation area. RESULTS:In the 38 patients with HCCs,20 (52.6%)were brighter than surrounding cirrhotic parenchyma. Another 13 (34.2%) were darker. The others (5 cases,13.2%) were seen as the same color as the adjacent liver parenchyma. Post-RFA lesions were darker than previous tumor and surrounding parenchyma in all 38 cases. However,recurred HCCs were brighter than the treated site in all 8 cases. CONCLUSION:Using ARFI technique is helpful for differential diagnosis in order to detect recurred HCCs more easily in patients with confusing status. 展开更多
关键词 Hepatocellular carcinoma ELASTOGRAPHY Radiofrequency ablation
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Histopathology and TB-PCR kit analysis in differentiating the diagnosis of intestinal tuberculosis and Crohn’s disease 被引量:20
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作者 Joon Mee Kim Hyung Kil Kim +6 位作者 Lucia Kim Suk Jin Choi In Suh Park Jee Young Han Young Chae Chu Kye Sook kwon Eun Joo Kim 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第20期2496-2503,共8页
AIM: To compare the histopathologic features of intestinal tuberculosis (ITB) and Crohn’s disease (CD) and to identify whether polymerase chain reaction for Mycobacterium tuberculosis (TB-PCR) would be helpful for di... AIM: To compare the histopathologic features of intestinal tuberculosis (ITB) and Crohn’s disease (CD) and to identify whether polymerase chain reaction for Mycobacterium tuberculosis (TB-PCR) would be helpful for differential diagnosis between ITB and CD.METHODS: We selected 97 patients with established diagnoses (55 cases of ITB and 42 cases of CD) who underwent colonoscopic biopsies.Microscopic features of ITB and CD were reviewed,and eight pathologic parameters were evaluated.Nine cases of acid fast bacilli culture-positive specimens and 10 normal colonic tissue specimens were evaluated as the positive and negative control of the TB-PCR test,respectively.PCR assays were done using two commercial kits: kit <A> detected IS6110 and MPB64,and kit <B> detected IS6110 only;a manual in-house PCR method was also performed on formalin-fi xed,paraffi n-embedded colonoscopic biopsy specimens.RESULTS: Statistically significant differences were noted between ITB and CD with regard histopathologic criteria: size of granulomas (P = 0.000),giant cells (P = 0.015),caseation necrosis (P = 0.003),confluent granulomas (P = 0.001),discrete granulomas (P = 0.000),and granulomas with lymphoid cuffs (P = 0.037).However,29 cases (52.7%) of ITB showed less than fi ve kinds of pathologic parameters,resulting in confusion with CD.The sensitivities and specificities of the TB-PCR test by kit <A>,kit <B>,and the in-house PCR method were 88.9% and 100%,88.9% and 100%,and 66.7% and 100% in positive and negative controls,respectively.The PCR test done on endoscopic biopsy specimens of ITB and CD were signifi cantly different with kit <A> (P = 0.000) and kit <B> (P = 0.000).The sensitivities and specifi cities of TB-PCR were 45.5% and 88.1%,36.4% and 100%,and 5.8% and 100%,for kit <A> and kit <B> and inhouse PCR method on endoscopic biopsy specimens.Among the 29 cases of histopathologically confusing CD,10 cases assayed using kit <A> and 6 cases assayed using kit <B> were TB-PCR positive.A combination of histologic fi ndings and TB-PCR test 展开更多
关键词 Intestine Tuberculosis Crohn’s disease HISTOPATHOLOGY Polymerase chain reaction KIT IS6110 MPB64
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沙地樟子松天然林南缘分布区林木竞争、空间格局及其更新特征 被引量:20
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作者 潘磊磊 kwon SEMYUNG +5 位作者 刘艳书 张晓 杨晓晖 山丹 朱媛君 时忠杰 《生态学报》 CAS CSCD 北大核心 2019年第10期3687-3699,共13页
以呼伦贝尔沙地樟子松地理分布南缘天然林为研究对象,采用Hegyi竞争指数与点格局等分析方法,研究了沙地樟子松天然林的种群结构、种内竞争、空间格局及幼树更新等特征。结果表明:1)所调查区域天然沙地樟子松纯林处于中幼龄阶段,属增长... 以呼伦贝尔沙地樟子松地理分布南缘天然林为研究对象,采用Hegyi竞争指数与点格局等分析方法,研究了沙地樟子松天然林的种群结构、种内竞争、空间格局及幼树更新等特征。结果表明:1)所调查区域天然沙地樟子松纯林处于中幼龄阶段,属增长型种群;2)其竞争指数与对象木胸径服从幂函数关系CI=242.24D^-1.12(R^2=0.91);3)幼树在小尺度上呈聚集分布,中树与大树在中大尺度上呈随机分布;幼树与中树在小尺度上呈正相关性,中树与大树在小尺度呈负相关性;4)竞争指数与更新幼树和存活更新幼树的密度均呈显著正相关性。在林分管理中需要充分考虑林木竞争、空间格局以及种群更新的关系,本研究可为沙地樟子松天然林的经营管理与保护提供重要的科学依据。 展开更多
关键词 沙地樟子松 竞争指数 点格局分析 种群更新
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Effect of Deformation Temperature on Microstructure and Mechanical Properties of AZ31 Mg Alloy Processed by Differential-Speed Rolling 被引量:19
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作者 Mosab Kaseem Bong kwon Chung +2 位作者 Hae Woong Yang Kotiba Hamad Young Gun Ko 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2015年第5期498-503,共6页
A differential-speed rolling(DSR) was applied to AZ31 magnesium alloy sample at different rolling temperatures of 473,523,573,and 623 K with 1-pass and 2-pass operations.The microstructural evolution and mechanical pr... A differential-speed rolling(DSR) was applied to AZ31 magnesium alloy sample at different rolling temperatures of 473,523,573,and 623 K with 1-pass and 2-pass operations.The microstructural evolution and mechanical properties of the deformed samples were investigated.The rolling temperature was found to be an important parameter affecting the microstructural development.After DSR at 473 K,the microstructure was more homogeneous than that obtained after deformation by equal-speed rolling(ESR).The fully recrystallized microstructures were generated after DSR at 573 and 623 K.As to mechanical properties,the yield strength(YS) and ultimate tensile strength(UTS) decreased monotonously with increasing rolling temperature.In contrast,the elongation of the DSR-deformed samples was improved as the rolling temperature increased.The strain hardening exponent(n) calculated by Hollomon equation increased with increasing the rolling temperature,which would explain an increase in the uniform elongation. 展开更多
关键词 Differential-speed rolling Magnesium alloy Mechani
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沙地天然樟子松径向生长对干旱的响应 被引量:15
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作者 张晓 潘磊磊 +3 位作者 Semyung kwon 刘艳书 杨晓晖 时忠杰 《北京林业大学学报》 CAS CSCD 北大核心 2018年第7期27-35,共9页
【目的】呼伦贝尔沙地为天然樟子松分布区的南缘,气候变化呈暖干化特点,研究该区樟子松树木径向生长对气候的响应及其应对干旱的能力,有助于促进气候变化背景下沙地天然樟子松林的保护与恢复。【方法】在呼伦贝尔沙地的南辉和伊敏河两... 【目的】呼伦贝尔沙地为天然樟子松分布区的南缘,气候变化呈暖干化特点,研究该区樟子松树木径向生长对气候的响应及其应对干旱的能力,有助于促进气候变化背景下沙地天然樟子松林的保护与恢复。【方法】在呼伦贝尔沙地的南辉和伊敏河两个地点建立了树轮宽度标准年表并对其变化进行比较,利用树轮宽度标准年表与气候因子进行相关分析,并计算樟子松应对极端干旱的抵抗力、恢复力和弹性力。【结果】南辉的樟子松标准年表与6月平均气温和6—7月平均最高气温呈显著负相关(P<0.05),伊敏河的樟子松年表与4月、6—7月和9月平均气温和平均最高气温呈显著负相关(P<0.05);两个地点的樟子松标准年表均与6—7月和9月的降水量正相关(P<0.1);南辉的樟子松年表与9月相对湿度呈显著负相关(P<0.05),但伊敏河的樟子松年表与前一年10—12月和当年2—3月和5月相对湿度显著正相关(P<0.05);两个地点的樟子松年表均与前一年10月至当年9月的帕尔默干旱胁迫指数(PDSI)呈显著正相关(P<0.05)。以上结果表明这一区域的樟子松径向生长受到水分的显著影响;与南辉的樟子松相比,伊敏河的樟子松对干旱的抵抗力较弱,但恢复力更强;随着干旱程度的增加,樟子松对极端干旱的抵抗力下降、恢复力增强。【结论】呼伦贝尔沙地天然樟子松径向生长受生长季气温和降水的共同影响;在1925—1935年间,两个地点的樟子松年表存在差异可能是由于伊敏河的樟子松处于幼龄,对干旱的抵抗能力较差;树龄可能会导致沙地天然樟子松应对干旱能力的差异,深入了解树龄对樟子松应对干旱能力的影响需进一步开展多点研究。 展开更多
关键词 呼伦贝尔沙地 樟子松 径向生长 气候响应 弹性力
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Design and performance simulation of a molecular Doppler wind lidar 被引量:17
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作者 沈法华 Hyunki Cha +3 位作者 董吉辉 Dukhyeon Kim 孙东松 Sung Ok kwon 《Chinese Optics Letters》 SCIE EI CAS CSCD 2009年第7期593-597,共5页
A mobile molecular Doppler wind lidar at an eye-safe wavelength of 355 nm based on double-edge technique is being built in Hefei (China) for wind measurement from 10-to 40-km altitude. The structure of this lidar sy... A mobile molecular Doppler wind lidar at an eye-safe wavelength of 355 nm based on double-edge technique is being built in Hefei (China) for wind measurement from 10-to 40-km altitude. The structure of this lidar system is described. A triple Fabry-Perot etalon is employed as a frequency discriminator whose parameters are optimized. The receiver system is designed to achieve compactness and stability by putting in a standard 19-inch socket bench. Simulation results show that within the wind speed dynamic range of ±100 m/s, the horizontal wind errors due to noise are less than 1 m/s bdow 20-km altitude for 100-m vertical resolution, and less than 5.5 m/s from 20 km up to 40 km for 500-m vertical resolution with 400-mJ laser energy, 30-min temporal resolution, and a 45-cm aperture telescooe. 展开更多
关键词 Optical radar
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Rice Transcription Factor OsDOFll Modulates Sugar Transport by Promoting Expression of Sucrose Transporter and SWEET Genes 被引量:17
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作者 Yunfei Wu Sang-Kyu Lee +5 位作者 Youngchul Yoo Jinhuan Wei Suk-Yoon kwon Sang-Won Lee Jong-Seong Jeon Gynheung An 《Molecular Plant》 SCIE CAS CSCD 2018年第6期833-845,共13页
Sucrose is produced in mesophyll cells and transferred into phloem cells before it is delivered long- distance to sink tissues. However, little is known about how sucrose transport is regulated in plants. Here, we ide... Sucrose is produced in mesophyll cells and transferred into phloem cells before it is delivered long- distance to sink tissues. However, little is known about how sucrose transport is regulated in plants. Here, we identified a T-DNA insertional mutant of Oryza sativa DNA BINDING WITH ONE FINGER 11 (OsDOF11), which is expressed in the vascular cells of photosynthetic organs and in various sink tissues. The osdofll mutant plants are semi-dwarf and have fewer tillers and smaller panicles as compared with wild-type (WT) plants. Although sucrose enhanced root elongation in young WT seedlings, this enhance- ment did not occur in osdof11 seedlings due to reduced sucrose uptake. Sugar transport rate analyses revealed that less sugar was transported in osdofll plants than in the WT. Expression of four Sucrose Transporter (SUT) genes-OsSUT1, OsSUT3, OsSUT4, and OsSUT5-as well as two Sugars Will Eventually be Exported Transporters (SWEET) genes, OsSWEETll and OsSWEET14, was altered in various organs of the mutant, including the leaves. Chromatin immunoprecipitation assays showed that OsDOFll directly binds the promoter regions of SUT1, OsSWEETll, and OsSWEET14, indicating that the expression of these transporters responsible for sucrose transport via apopiastic loading is coordinately controlled by OsDOFll. We also observed that osdofll mutant plants were less susceptible to infection byXanthomonas oryzae pathovar oryzae, suggesting that OsDOFll participates in sugar distribution during pathogenic in- vasion. Collectively, these results suggest that OsDOFll modulates sugar transport by regulating the expression of both SUT and SWEET genes in rice. 展开更多
关键词 OsDOF11 phloem loading RICE SUT SWEET Xanthomonas oryzae
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Salt Tolerance in Rice: Focus on Mechanisms and Approaches 被引量:17
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作者 Inja Naga Bheema Lingeswara REDDY Beom-Ki KIM +2 位作者 In-Sun YOON Kyung-Hwan KIM Taek-Ryoun kwon 《Rice science》 SCIE CSCD 2017年第3期123-144,共22页
Salt tolerance is an important constrain for rice, which is generally categorized as a typical glycophyte. Soil salinity is one of the major constraints affecting rice production worldwide, especially in the coastal a... Salt tolerance is an important constrain for rice, which is generally categorized as a typical glycophyte. Soil salinity is one of the major constraints affecting rice production worldwide, especially in the coastal areas. Susceptibility or tolerance of rice plants to high salinity is a coordinated action of multiple stress responsive genes, which also interacts with other components of stress signal transduction pathways. Salt tolerant varieties can be produced by marker-assisted selection or genetic engineering by introducing salt-tolerance genes. In this review, we have updated on mechanisms and genes which can help in transferring of the salt tolerance into high-yielding rice varieties. We have focused on the need for integrating phenotyping, genomics, metabolic profiling and phenomics into transgenic and breeding approaches to develop high-yielding as well as salt tolerant rice varieties. 展开更多
关键词 RICE mechanism SALINITY SALT TOLERANCE yield gene protein
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不同竞争强度下的沙地樟子松天然林树木径向生长及其气候响应 被引量:14
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作者 SeMyung kwon 潘磊磊 +4 位作者 时忠杰 杨晓晖 张晓 刘艳书 张克斌 《生态学杂志》 CAS CSCD 北大核心 2019年第7期1962-1972,共11页
以呼伦贝尔沙地樟子松天然林为研究对象,采用竞争指数与树木年代学等分析方法,研究了竞争对樟子松树木径向生长及其气候响应的影响。结果表明:竞争显著影响了沙地樟子松树木的生长;竞争能力强的树木主要对当年生长季的月均最高温度、降... 以呼伦贝尔沙地樟子松天然林为研究对象,采用竞争指数与树木年代学等分析方法,研究了竞争对樟子松树木径向生长及其气候响应的影响。结果表明:竞争显著影响了沙地樟子松树木的生长;竞争能力强的树木主要对当年生长季的月均最高温度、降水和相对湿度响应更加敏感,而竞争能力弱的树木则对前一年冬季月均最低温度、前一年生长季的降水和相对湿度的响应更加敏感;低竞争指数和高竞争指数组的树木,特别是竞争力较强的树木对干旱的响应非常敏感,而中等竞争能力的树木干旱响应较不敏感。综合来看,林木之间的竞争关系对沙地樟子松树木生长及其气候响应具有较显著的影响,本研究可为气候变化背景下樟子松天然林的经营与管理提供一定的科学依据。 展开更多
关键词 竞争指数 径向生长 气候敏感性 樟子松
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Association between preoperative high sensitive troponin I levels and cardiovascular events after hip fracture surgery in the elderly 被引量:16
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作者 Bum Sung Kim Tae-Hoon Kim +5 位作者 Jeong-Hwan Oh Chang Hee kwon Sung Hea Kim Hyun-Joong Kim Heung Kon Hwang Sang-Man Chung 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2018年第3期215-221,共7页
Objective Cardiovascular complications contribute to postoperative morbidity and mortality in elderly hip fracture patients. Limited data are available regarding which preoperative risk factors predict cardiovascular ... Objective Cardiovascular complications contribute to postoperative morbidity and mortality in elderly hip fracture patients. Limited data are available regarding which preoperative risk factors predict cardiovascular course following hip fracture surgery (HFS). We used high sensitive troponin I (hs-TnI) assays and clinical parameters to identify preoperative risk factors associated with major adverse cardiac events (MACE) in elderly hip frac^u'e patients. Method From August 2014 to November 2016, 575 patients with hip fracture were enrolled in a retrospective, single-center registry. A total of 262 of these patients underwent HFS and hs-TnI assays. MACE was defined as postoperative all-cause deaths, heart failure (HF), new-onset atrial fibrillation (AF), myocardial infarction (MI) and cardiovascular re-hospitalization that occurred within 90 days postoperative. Results Of 262 HFS patients, MACE developed following HFS in 65 (24.8%). Patients with MACE were older and had higher rates of renal insufficiency, coronary artery disease, prior HF, low left ventricular ejection fraction and use of beta blockers; higher levels of hs-Tnl and N-terminal pro-brain natriuretic peptide (NT-proBNP) and higher revised cardiac risk index. A preoperative hs-TnI≥ 6.5 ng/L was associated with high risk of postoperative HF, new-onset AF and MACE. In multivariable analysis, pre-operative independent predictors for MACE were age 〉 80 years [adjusted hazard ratio (HR): 1.79, 95% confident interval (CI): 1.03-3.13, P = 0.04], left ventricular ejection fraction (LVEF) 〈 50% (adjusted HR: 3.17, 95% CI: 1.47-5.82, P 〈 0.01) and hs-TnI 〉 6.5 ng/L (adjusted HR: 3.75, 95% CI: 2.09~5.17, P 〈 0.01). Conclusion In elderly patients with hip fracture who undergo HFS, a preoperative assessment of hs-TnI may help the risk refinement of cardiovascular complications. 展开更多
关键词 Cardiovascular complication High sensitive troponin I Hip fracture surgery
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Fabrication of 3D Printed PCL/PEG Polyblend Scaffold Using Rapid Prototyping System for Bone Tissue Engineering Application 被引量:16
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作者 Su A Park Sang Jin Lee +3 位作者 Ji Min Seok Jun Hee Lee Wan Doo Kim Il Keun kwon 《Journal of Bionic Engineering》 SCIE EI CSCD 2018年第3期435-442,共8页
Three-dimensional (3D) printing is a novel process used to manufacture bone tissue engineered scaffolds. This process allows for easy control of the architecture at the micro structure. However, the scaffold propert... Three-dimensional (3D) printing is a novel process used to manufacture bone tissue engineered scaffolds. This process allows for easy control of the architecture at the micro structure. However, the scaffold properties are typically limited in terms of cellular activity at the scaffold surface due to the printed materials properties. In this study, we developed a polycaprolactone (PCL) blended with polyethylene glycol (PEG) 3D printed scaffold using a rapid prototyping system. The manufactured scaffolds were then washed out to form small pores on the surface in order to improve the scaffolds hydrophilicity. We analyzed the resultant material by using Scanning Electron Microscopy (SEM), water absorption, water contact angle, in vitro WST-1, and the Bradford assay. Additionally, cells incubated on the fabricated scaffolds were visualized by Confocal Laser Scanning Microscopy (CLSM). The developed scaffolds exhibited small pores on the strand surface which served to increase hydrophilicity as well as improve cellular proliferation and increase total protein content. Our findings suggest that the presence of small pores on the scaffolds can be used as an effective tool for improving implant cellular interaction. This research indicates that these modified scaffolds can be considered useful for bone tissue engineering applications to improve human health. 展开更多
关键词 POLYCAPROLACTONE polyethylene glycol polyblend 3D printing POROSITY bone tissue engineering
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Long-term follow up of endoscopic resection for type 3 gastric NET 被引量:16
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作者 Yong Hwan kwon Seong Woo Jeon +8 位作者 Gwang Ha Kim Jin Il Kim Il-Kwun Chung Sam Ryong Jee Heung Up Kim Geom Seog Seo Gwang Ho Baik Kee Don Choi Jeong Seop Moon 《World Journal of Gastroenterology》 SCIE CAS 2013年第46期8703-8708,共6页
AIM:To clarify the short and long-term results and to prove the usefulness of endoscopic resection in type 3gastric neuroendocrine tumors(NETs).METHODS:Of the 119 type 3 gastric NETs diagnosed from January 1996 to Sep... AIM:To clarify the short and long-term results and to prove the usefulness of endoscopic resection in type 3gastric neuroendocrine tumors(NETs).METHODS:Of the 119 type 3 gastric NETs diagnosed from January 1996 to September 2011,50 patients treated with endoscopic resection were enrolled in this study.For endoscopic resection,endoscopic mucosal resection(EMR)or endoscopic submucosal dissection(ESD)was used.Therapeutic efficacy,complications,and follow-up results were evaluated retrospectively.RESULTS:EMR was performed in 41 cases and ESD in 9 cases.Pathologically complete resection was performed in 40 cases(80.0%)and incomplete resection specimens were observed in 10 cases(7 vs 3 patients in the EMR vs ESD group,P=0.249).Upon analysis of the incomplete resection group,lateral or vertical margin invasion was found in six cases(14.6%)in the EMR group and in one case in the ESD group(11.1%).Lymphovascular invasions were observed in two cases(22.2%)in the ESD group and in one case(2.4%)in the EMR group(P=0.080).During the follow-up period(43.73;13-60 mo),there was no evidence of tumor recurrence in either the pathologically complete resection group or the incomplete resection group.No recurrence was reported during follow-up.In addition,no mortality was reported in either the complete resection group or the incomplete resection group for the duration of the follow-up period.CONCLUSION:Less than 2 cm sized confined submucosal layer type 3 gastric NET with no evidence of lymphovascular invasion,endoscopic treatment could be considered at initial treatment. 展开更多
关键词 STOMACH NEUROENDOCRINE tumor Endo-scopic RESECTION Treatment CARCINOID
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Effect of vehicle weight on natural frequencies of bridges measured from traffic-induced vibration 被引量:16
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作者 Chul-Young Kim Dae-Sung Jung +2 位作者 Nam-Sik Kim Soon-Duck kwon Maria Q.Feng 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2003年第1期109-116,共8页
Recently,ambient vibration test(AVT)is widely used tu estimate dynamic characteristics of large civil struc- tures.Dynamic characteristics ean be affected by various envirnnmental factors such as humidity,intensity of... Recently,ambient vibration test(AVT)is widely used tu estimate dynamic characteristics of large civil struc- tures.Dynamic characteristics ean be affected by various envirnnmental factors such as humidity,intensity of wind,and temperature.Besides these environmental conditions,tire mass of vehicles may change the measured valnes when traffic-in- duced vibration is used as a source of AVT tor bridges.The effect of vehicle mass on dynamic characteristics is investigated through traffic-induced vibration tests on three bridges;(1)three-span suspension bridge(128m+404m+128m),(2) five-span continuous steel box girder bridge(59m+3@ 95m+59m),(3)simply supported plate girder bridge(46m). Acceleration histories of each measurement location under normal traffic are recorded for 30 minutes at field.These recor- ded histories are divided into individual vibrations and are combined into two groups aceording to the level of vibration;one by heavy vehicles such as trucks and buses and the other by light vehicles such as passenger cars.Separate processing of the two groups of signals shows that,for the middle and long-span bridges,the difference can be hardly detected,but,for the short span bridges whose mass is relatively small,the measured natural frequencies can change up to 5.4%. 展开更多
关键词 ambient vibration test traffic induced vibration vehicle mass suspension bridge short-span bridge dynamic characteristics natural frequency
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Molecular mechanisms of apoptosis induced by Scorpio water extract in human hepatoma HepG2 cells 被引量:9
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作者 Kang-Beom kwon Eun-Kyung Kim +6 位作者 Jung-Gook Lim Eun-Sil Jeong Byung-Cheul Shin Young-Se Jeon Kang-San Kim Eun-A Seo Do-Gon Ryu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第7期943-947,共5页
AIM: To clarify the mechanism underlying the anti-mutagenic and anti-cancer activities of Scorpio water extract (SWE). METHODS: Human hepatoma HepG2 cells were incubated with various concentrations of SWE. After 24-h ... AIM: To clarify the mechanism underlying the anti-mutagenic and anti-cancer activities of Scorpio water extract (SWE). METHODS: Human hepatoma HepG2 cells were incubated with various concentrations of SWE. After 24-h incubation, cytotoxicity and apoptosis evaluations were determined by MTT and DNA fragmentation assay, respectively. After treatment with SWE, mitochondrial membrane potential (MMP) was determined by measuring the retention of the dye 3,3'-dihexyloxacarbocyanine (DiOC6(3)) and the protein expression including cytochrome C and poly-(ADPribose) polymerase (PARP) were measured by Western blotting. Caspase-3 and -9 enzyme activities were measured using specific fluorescence dyes such as Ac-DEVD-AFC and Ac-LEHD-AFC. RESULTS: We found that treatment with SWE induced apoptosis as confirmed by discontinuous DNA fragmentation in cultured human hepatoma HepG2 cells. Our investigation also showed that SWE-induced apoptosis of HepG2 cells were associated with intracellular events including disruption of MMP, increased translocation of cytochrome C from mitochondria to cytosol, activation of caspase-3, and PARP. Pre-treatment of N-acetyl-Asp-Glu-Val-Asp-CHO (Ac-DEVD-CHO), a caspase-3 specific inhibitor, or cyclosporin A (CsA), an inhibitor of MMP disruption, completely abolished SWE-induced DNA fragmentation. CONCLUSION: These results suggest that SWE possibly causes mitochondrial damage, leading to cytochrome C release into cytosol and activation of caspases resulting in PARP cleavage and execution of apoptotic cell death in HepG2 cells. These results further suggest that Scorpio may be a valuable agent of therapeutic intervention of human hepatomas. 展开更多
关键词 SCORPIO Human hepatoma HepG2 cell APOPTOSIS
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