检索结果-南通市图书馆

Protective effect of estradiol on hepatocytic oxidative damage

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2002年第2期8卷 363-366页

作者： Ichiro Shimizu Toshihiro Omoya Susumu ito Second Department of Internal Medicine School of MedicineUniversity of TokushimaTokushima770-8503Japan

AIM: To examine the protective effect of estradiol on the cultured hepatocytes under oxidative stress. METHODS: Hepatocytes of rat were isolated by using perfusion method, and oxidative stress was induced by a serum-free medium and FeNTA. MDA level was determined with TBA method. Cell damage was assessed by LDH assay. Apoptosis of hepatocytes was assessed with cytoflowmetric analysis. Expression of Bcl-xl in cultured hepatocytes was detected by Western blot. The radical-scavenging activity of estradiol was valued by its ability to scavenge the stable free radical of DDPH. RESULTS: Oxidative stress increased LDH from 168 +/- 25 x 10(-6)***(-1) to 780 +/- 62 x 10(-6)***(-1) and MDA(from 0.28 +/- 0.07 x 10(-6)***(-1) to 1.35 +/- 0.12 x 10(-6)***(-1)) levels in cultured hepatocyte, and estradiol inhibited both LDH and MDA production in a dose dependent manner. In the presence of estradiol 10(-6)mol.L(-1), 10( -7 )mol.L(-1) and 10(-8)mol.L(-1),the LDH levels are 410 +/- 53 x 10(-6)***(-1) (P<0.01 vs oxidative group), 530 +/- 37 X 10(-6)***(-1 ) (P<0.01 vs oxidative group), 687+/-42 x 10(-6)***(-1) (P<0.05 vs oxidative group) respectively, and the MDA level are 0.71+/-0.12 x 10(-6)***(-1) (P<0.01 vs oxidative group),0.97+/-0.11 x 10(-6)***(-1 )(P<0.01 vs oxidative group) and 1.27+/-0.19 x 10(-6)***(-1) respectively. Estradiol suppressed apoptosis of hepatocytes induced by oxidative stress, administration of estradiol(10(-6)mol/L)decreased the apoptotic rate of hepatocytes under oxidative stress from 18.6 +/- 1.2% to 6.5 +/-2.5%, P<0.01. Bcl-xl expression was related to the degree of liver cell damage due to oxidative stress, and estradiol showed a protective action. CONCLUSION: Estradiol protects hepatocytes from oxidative damage by means of its antioxidant activity.

关键词： Oxidative Stress Animals Apoptosis Cells, Cultured Estradiol Female Flow Cytometry Hepatocytes L-Lactate Dehydrogenase Lipid Peroxidation Male Proto-Oncogene Proteins c-bcl-2 Rats Rats, Wistar Thiobarbituric Acid Reactive Substances bcl-X Protein

Diagnosis of Zollinger-Ellison syndrome:Increasingly difficult

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2012年第39期18卷 5495-5503页

作者： Tetsuhide ito Guillaume Cadiot Robert T Jensen Department of Medicine and Bioregulatory Science Graduate School of Medical SciencesKyushu UniversityFukuoka 812-8582Japan Hepato-Gastroenterology Service Centre hospitalier universitaire de ReimsHospital Robert DebreF-51092 ReimsFrance Digestive Diseases Branch National Insitutes of DiabetesDigestive and Kidney DiseasesNational Institutes of HealthBethesdaMD 20892United States

In the present paper the increasing difficulty of diag-nosis of Zollinger-Ellison syndrome (ZES) due to issues raised in two recent papers is discussed. These issues involve the difficulty and need to withdraw patients suspected of ZES from treatment with Proton Pump Inhibitors (omeprazole, esomeprazole, lansoprazole, rabeprazole, pantoprazole) and the unreliability of many gastrin radioimmunoassays. The clinical context of each of these important issues is reviewed and the conclusions in these articles commented from the per-spective of clinical management.

关键词： Zollinger-Ellison syndrome Gastrinoma Hypergastrinemia Secretin test Serum gastrin Gas-trin Neuroendocrine tumor

LOV Domain-Containing Light-Dependent Protein in Arabidopsis F-Box Proteins： Degradation Modules

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular Plant 2012年第3期5卷 573-582页

作者： Shogo ito Young Hun Song Takato Imaizumi Department of Biology Seattle WA 98195-1800 USA University of Washington Seattle WA 98195-1800 USA

Plants constantly survey the surrounding environment using several sets of photoreceptors. They can sense changes in the quantity （= intensity） and quality （=wavelength） of light and use this information to adjust their physiological responses, growth, and developmental patterns. In addition to the classical photoreceptors, such as phytochromes, crypto- chromes, and phototropins, ZEITLUPE （ZTL）, FLAVIN-BINDING, KELCH REPEAT, F-BOX 1 （FKF1）, and LOV KELCH PROTEIN 2 （LKP2） proteins have been recently identified as blue-light photoreceptors that are important for regulation of the circadian clock and photoperiodic flowering. The ZTL/FKF1/LKP2 protein family possesses a unique combination of domains： a blue-light-absorb- ing LOV （Light, Oxygen, or Voltage） domain along with domains involved in protein degradation. Here, we summarize recent advances in our understanding of the function of the Arabidopsis ZTL/FKF1/LKP2 proteins. We summarize the distinct pho- tochemical properties of their LOV domains and discuss the molecular mechanisms by which the ZTL/FKF1/LKP2 proteins reg- ulate the circadian clock and photoperiodic flowering by controlling blue-light-dependent protein degradation.

关键词： blue light LOV domain ZTL FKF1 LKP2 photoperiodic flowering circadian clock Arabidopsis

Profile and removal of endocrine disrupting chemicals by using an ER/AR competitive ligand binding assay and chemical analyses

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2009年第7期21卷 900-906页

作者： Ze-hua Liu Mamoru ito Yoshinori Kanjo Atsushi Yamamoto Department of Urban Engineering Graduate School of Engineering Osaka City University 3-3-138 Sugimoto Sumiyoshi-ku Osaka 558-8585 Japan Osaka City Institute of Public Health and Environmental Sciences 8-34 Tojo-cho Tennoji-ku Osaka 543-0026 Japan

An estrogen receptor （ER）/androgen receptor （AR） ligand competitive binding assay （ER/AR-binding assay） and chemical analyses were used to evaluate the endocrine disrupting chemicals （EDCs） behavior of two municipal wastewater treatment plants （WWTPs）（K and S）. In the influents, estrone （E 1）, androsterone （A）, androstenedione （AD）, BPA （bisphenol A）, NP （nonylphenol） and daidzein （DZ） were detected in high amounts with subsequent 24 h-average concentrations of 350, 1000, 29, 1300, 3900, and 5700 ng/L in K-WWTP and of 310, 620, 59, 1600, 2600, and 8400 ng/L in S-WWTP. The estrogenic （androgenic） activity as 17β-estradiol （E2） equivalents （EEQ） or testosterone （Te） equivalents （TEQ） was consequently 620 ng E2/L （570 ng Te/L） and 580 ng E2/L （800 ng Te/L） for the two WWTPs. The removal efficiencies of the above mentioned sole target chemicals were 51%-100% for K-WWTP and 55.6%-100% for S-WWTP. The removal efficiencies of EEQ were about 73% for both WWTPs, while the removal efficiencies of TEQ were 62.1% for K-WWTP and 98.4% for S-WWTP. In addition, chemical-derived EEQ were about 1.2%-52.4% of those by ER-binding assay for K-WWTP and the corresponding ratios were 1.3%-83.3% for S-WWTP, while chemical derived TEQ were less than 3% of values measured by the AR-binding assay for both WWTPs.

关键词： bioassays ER-binding AR-binding 17β-estradiol equivalents testosterone equivalents

Influence of collagen fibre orientation on the frictional properties of articular cartilage

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Biosurface and Biotribology 2021年第2期7卷 90-97页

作者： Seido Yarimitsu Kei ito Hiromichi Fujie Graduate School of Systems Design Tokyo Metropolitan UniversityHachiojiTokyoJapan

Articular cartilage has a unique collagen fibre network structure that exhibits both anisotropy and depth *** fibre orientation in a cross-section parallel to the articular cartilage surface may affect the lubrication properties of articular *** effect of collagen fibre orientation on the frictional properties of articular cartilage was examined through finite element analysis of the ***,a three-dimensional fibre-reinforced poroelastic biphasic model was used to determine the influence of collagen fibril orientation on the frictional properties of articular *** simulations reveal that collagen fibre orientation has a significant influence on the deformation behaviour of articular cartilage in front of and behind the contact *** coefficient of dynamic friction was lower in the direction parallel to the collagen fibre orientation than in the direction perpendicular to the collagen fibre orientation,regardless of the indenter speed.

关键词： friction fibre deformation

Ultrasonic measurements of single-crystal gold under hydrostatic pressures up to 8 GPa in a Kawai-type multi-anvil apparatus

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2007年第12期52卷 1600-1606页

作者： SONG MaoShuang Akira YONEDA Eiji ito Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Institute for Study of the Earth Interior Okayama University Misasa Tottori-ken 683-0193 Japan

Ultrasonic measurements were conducted on single-crystal gold at ambient condition and hydrostatic pressures up to 8 GPa at room temperature in a Kawai-type multi-anvil apparatus. The P-wave velocities measured at high pressures were in good agreement with Daniels and Smith’s ultrasonic study. The three independent elastic constants of gold at ambient condition were determined to be C11=192.7 GPa, C12=162.9 GPa, and C44=42.4 GPa. On the basis of an analysis of previous elastic data and the present ultrasonic data, the pressure derivatives of three elastic constants were estimated to be C1 ′1= 7.12,C 1′2 = 6.24,and C4′4 = 1.82. The calculated values of isothermal bulk modulus (KT0) and its pressure derivatives ( KT ′0) are KT0 = 166.44 GPa and KT ′0= 6.56. This indicates that Anderson et al.’s model of equation of state of gold might underestimates pressure about 1 GPa at pressure around 23 GPa and ambient temperature. Our results explained the discrepancies among the models of equation of state of gold proposed previously.

关键词：单晶体黄金超声波测量高温高压实验流体静力学状态方程

The Sensitivity Analysis for the Flow Past Obstacles Problem with Respect to the Reynolds Number

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Advances in Applied Mathematics and Mechanics 2012年第1期4卷 21-35页

作者： Kazufumi ito Zhilin Li Zhonghua Qiao Center for Research in Scientific Computation&Department of Mathematics North Carolina State UniversityRaleighNC 27695-8205USA School of Mathematical Sciences Nanjing Normal UniversityNo.1 Wenyuan RoadYadong New DistrictNanjing 210046China Department of Mathematics Hong Kong Baptist UniversityKowloon TongHong Kong

In this paper,numerical sensitivity analysis with respect to the Reynolds number for the flow past obstacle problem is *** carry out such analysis,at each time step,we need to solve the incompressible Navier-Stokes equations on irregular domains twice,one for the primary variables;the other is for the sensitivity variables with homogeneous boundary *** Navier-Stokes solver is the augmented immersed interface method for Navier-Stokes equations on irregular *** of the most important contribution of this paper is that our analysis can predict the critical Reynolds number at which the vortex shading begins to develop in the wake of the *** interesting experiments are shown to illustrate how the critical Reynolds number varies with different geometric settings.

关键词： Navier-Stokes equations sensitivity analysis flow past cylinder embedding technique immersed interface method irregular domain augmented system projection method fluid-solid interaction

Hypoxia-inducible factor 1 alpha and vascular endothelial growth factor overexpression in ischemic colitis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2005年第10期11卷 1535-1539页

作者： Tomoyuki Okuda Takeshi Azuma Masahiro Ohtani Ryuho Masaki Yoshiyuki ito Yukinao Yamazaki Shigeji ito Masaru Kuriyama Second Department of Internal Medicine Department of Endoscopic Medicine Department of Internal Medicine

AIM: To examine the etiology and pathophysiology in human ischemic colitis from the viewpoint of ischemic factors such as hypoxia-inducible factor 1 alpha (HIF-1 alpha and vascular endothelial growth factor (VEGF). METHODS: Thirteen patients with ischemic colitis and 21 normal controls underwent colonoscopy. The follow-up colonoscopy was performed in 8 patients at 7 to 10 d after the occurrence of ischemic colitis. Biopsy samples were subjected to real-time RT-PCR and immunohistochemistry to detect the expression of HIF-1 alpha and VEGF. RESULTS: HIF-1 alpha and VEGF expression were found in the normal colon tissues by RT-PCR and immunohistochemistry. HIF-1 alpha and VEGF were overexpressed in the lesions of ischemic colitis. Overexpressed HIF-1 alpha and VEGF RNA quickly decreased to the normal level in the scar regions at 7 to 10 d after the occurrence of ischemic colitis. CONCLUSION: Constant expression of HIF-1 alpha and VEGF in normal human colon tissue suggested that HIF-1 alpha and VEGF play an important role in maintaining tissue integrity. We confirmed the ischemic crisis in ischemic colitis at the molecular level, demonstrating overexpression of HIF-1 alpha and VEGF in ischemic lesions. These ischemic factors may play an important role in the pathophysiology of ischemic colitis.

关键词： Ischemic colitis HIF-1 alpha VEGF

Functional relationship between p53 and RUNX proteins

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Molecular Cell Biology 2019年第3期11卷 224-230页

作者： Suk-Chul Bae Arun Mouli Kolinjivadi Yoshiaki ito Department of Biochemistry School of Medicineand Institute for Tumour ResearchChungbuk National UniversityCheongju 28644South Korea Cancer Science Institute of Singapore National University of SingaporeSingapore 117599Singapore

RUNX genes belong to a three-membered family of transcription factors,which are well established as master regulators of *** them,aberrations in RUNX3 expression are frequently observed in human malignancies primarily due to epigenetic silencing,which is often *** the G1 phase of the cell cycle,RUNX3 regulates the restriction(R)-point,a mechanism that decides cell cycle *** at the R-point or loss of RUNX3 results in premature entry into S phase,leading to a proliferative *** of Runxl and Runx2 induce immortalization of mouse embryo *** a consequence,RUNX loss induces pre-cancerous lesions independent of oncogene activation.p53 is the most extensively studied tumour suppressor.p53 plays an important role to prevent tumour progression but not tumour ***,upon oncogene activation,early inactivation of RUNX genes and subsequent mutation of p53 appear to result in tumour initiation and ***,transcription-independent DNA repairing roles of RUNX3 and p53 are *** evolutionarily old genes,it appears that the primordial function of p53 is to protect genome integrity,a function that likely extends to the RUNX gene as *** this review,we examine the mechanism and sequence of actions of these tumour suppressors in detail.

关键词： RUNX tumour suppressor p53