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Gnatiuc L, Herrington WG, Halsey J, Tuomilehto J, Fang X, Kim HC, De Bacquer D, Dobson AJ, Criqui MH, Jacobs DR, Leon DA, Peters SAE, Ueshima H, Sherliker P, Peto R, Collins R, Huxley RR, Emberson JR, Woodward M, Lewington S, Aoki N, Arima H, Arnesen E, Aromaa A, Assmann G, Bachman DL, Baigent C, Bartholomew H, Benetos A, Bengtsson C, Bennett D, Björkelund C, Blackburn H, Bonaa K, Boyle E, Broadhurst R, Carstensen J, Chambless L, Chen Z, Chew SK, Clarke R, Cox C, Curb JD, D'Agostino R, Date C, Davey Smith G, De Backer G, Dhaliwal SS, Duan XF, Ducimetiere P, Duffy S, Eliassen H, Elwood P, Empana J, Garcia-Palmieri MH, Gazes P, Giles GG, Gillis C, Goldbourt U, Gu DF, Guasch-Ferre M, Guize L, Haheim L, Hart C, Hashimoto S, Hashimoto T, Heng D, Hjermann I, Ho SC, Hobbs M, Hole D, Holme I, Horibe H, Hozawa A, Hu F, Hughes K, Iida M, Imai K, Imai Y, Iso H, Jackson R, Jamrozik K, Jee SH, Jensen G, Jiang CQ, Johansen NB, Jorgensen T, Jousilahti P, Kagaya M, Keil J, Keller J, Kim IS, Kita Y, Kitamura A, Kiyohara Y, Knekt P, Knuiman M, Kornitzer M, Kromhout D, Kronmal R, Lam TH, Law M, Lee J, Leren P, Levy D, Li YH, Lissner L, Luepker R, Luszcz M, MacMahon S, Maegawa H, Marmot M, Matsutani Y, Meade T, Morris J, Morris R, Murayama T, Naito Y, Nakachi K, Nakamura M, Nakayama T, Neaton J, Nietert PJ, Nishimoto Y, Norton R, Nozaki A, Ohkubo T, Okayama A, Pan WH, Puska P, Qizilbash N, Reunanen A, Rimm E, Rodgers A, Saitoh S, Sakata K, Sato S, Schnohr P, Schulte H, Selmer R, Sharp D, Shifu X, Shimamoto K, Shipley M, Silbershatz H, Sorlie P, Sritara P, Suh I, Sutherland SE, Sweetnam P, Tamakoshi A, Tanaka H, Thomsen T, Tominaga S, Tomita M, Törnberg S, Tunstall-Pedoe H, Tverdal A, Ueshima H, Vartiainen E, Wald N, Wannamethee SG, Welborn TA, Whincup P, Whitlock G, Willett W, Woo J, Wu ZL, Yao SX, Yarnell J, Yokoyama T, Yoshiike N, Zhang XH. Sex-specific relevance of diabetes to occlusive vascular and other mortality: a collaborative meta-analysis of individual data from 980 793 adults from 68 prospective studies. Lancet Diabetes Endocrinol 2018; 6:538-546. [PMID: 29752194 PMCID: PMC6008496 DOI: 10.1016/s2213-8587(18)30079-2] [Citation(s) in RCA: 129] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 02/20/2018] [Accepted: 02/26/2018] [Indexed: 01/06/2023]
Abstract
BACKGROUND Several studies have shown that diabetes confers a higher relative risk of vascular mortality among women than among men, but whether this increased relative risk in women exists across age groups and within defined levels of other risk factors is uncertain. We aimed to determine whether differences in established risk factors, such as blood pressure, BMI, smoking, and cholesterol, explain the higher relative risks of vascular mortality among women than among men. METHODS In our meta-analysis, we obtained individual participant-level data from studies included in the Prospective Studies Collaboration and the Asia Pacific Cohort Studies Collaboration that had obtained baseline information on age, sex, diabetes, total cholesterol, blood pressure, tobacco use, height, and weight. Data on causes of death were obtained from medical death certificates. We used Cox regression models to assess the relevance of diabetes (any type) to occlusive vascular mortality (ischaemic heart disease, ischaemic stroke, or other atherosclerotic deaths) by age, sex, and other major vascular risk factors, and to assess whether the associations of blood pressure, total cholesterol, and body-mass index (BMI) to occlusive vascular mortality are modified by diabetes. RESULTS Individual participant-level data were analysed from 980 793 adults. During 9·8 million person-years of follow-up, among participants aged between 35 and 89 years, 19 686 (25·6%) of 76 965 deaths were attributed to occlusive vascular disease. After controlling for major vascular risk factors, diabetes roughly doubled occlusive vascular mortality risk among men (death rate ratio [RR] 2·10, 95% CI 1·97-2·24) and tripled risk among women (3·00, 2·71-3·33; χ2 test for heterogeneity p<0·0001). For both sexes combined, the occlusive vascular death RRs were higher in younger individuals (aged 35-59 years: 2·60, 2·30-2·94) than in older individuals (aged 70-89 years: 2·01, 1·85-2·19; p=0·0001 for trend across age groups), and, across age groups, the death RRs were higher among women than among men. Therefore, women aged 35-59 years had the highest death RR across all age and sex groups (5·55, 4·15-7·44). However, since underlying confounder-adjusted occlusive vascular mortality rates at any age were higher in men than in women, the adjusted absolute excess occlusive vascular mortality associated with diabetes was similar for men and women. At ages 35-59 years, the excess absolute risk was 0·05% (95% CI 0·03-0·07) per year in women compared with 0·08% (0·05-0·10) per year in men; the corresponding excess at ages 70-89 years was 1·08% (0·84-1·32) per year in women and 0·91% (0·77-1·05) per year in men. Total cholesterol, blood pressure, and BMI each showed continuous log-linear associations with occlusive vascular mortality that were similar among individuals with and without diabetes across both sexes. INTERPRETATION Independent of other major vascular risk factors, diabetes substantially increased vascular risk in both men and women. Lifestyle changes to reduce smoking and obesity and use of cost-effective drugs that target major vascular risks (eg, statins and antihypertensive drugs) are important in both men and women with diabetes, but might not reduce the relative excess risk of occlusive vascular disease in women with diabetes, which remains unexplained. FUNDING UK Medical Research Council, British Heart Foundation, Cancer Research UK, European Union BIOMED programme, and National Institute on Aging (US National Institutes of Health).
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Bugnet M, Overbury SH, Wu ZL, Epicier T. Direct Visualization and Control of Atomic Mobility at {100} Surfaces of Ceria in the Environmental Transmission Electron Microscope. Nano Lett 2017; 17:7652-7658. [PMID: 29166035 DOI: 10.1021/acs.nanolett.7b03680] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Ceria is one of the world's most prominent material for applications in heterogeneous catalysis, as catalyst support or catalyst itself. Despite an exhaustive literature on the structure of reactive facets of CeO2 in line with its catalytic mechanisms, the temporal evolution of the atomic surface structure exposed to realistic redox conditions remains elusive. Here, we provide a direct visualization of the atomic mobility of cerium atoms on {100} surfaces of CeO2 nanocubes at room temperature in high vacuum, O2, and CO2 atmospheres in an environmental transmission electron microscope. Through quantification of the cationic mobility, we demonstrate the control of the surface dynamics under exposure to O2 and CO2 atmospheres, providing opportunities for a better understanding of the intimate catalytic mechanisms.
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Affiliation(s)
- M Bugnet
- University of Lyon, INSA Lyon, UCBL Lyon 1, MATEIS, UMR 5510 CNRS , 69100 Villeurbanne Cedex, France
| | - S H Overbury
- Chemical Science Division, Center for Nanophase Materials Science, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Z L Wu
- Chemical Science Division, Center for Nanophase Materials Science, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - T Epicier
- University of Lyon, INSA Lyon, UCBL Lyon 1, MATEIS, UMR 5510 CNRS , 69100 Villeurbanne Cedex, France
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Tang RH, Ye RH, Yang YC, Yao ST, Wang JB, Zhang RM, Luo LF, Wu ZL, Long YC, Yin MS, He N, Duan S. [A cross-sectional survey of receiving no methadone maintenance treatment in HIV infected injecting drug users in Dehong Dai and Jingpo autonomous prefecture, Yunnan province]. Zhonghua Liu Xing Bing Xue Za Zhi 2017; 38:336-340. [PMID: 28329935 DOI: 10.3760/cma.j.issn.0254-6450.2017.03.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To understand the current status of receiving no methadone maintenance treatment (MMT) and influencing factors in HIV infected injecting drug users (IDUs) in Dehong Dai and Jingpo autonomous prefectures, Yunnan province. Methods: Data of survival of IDUs with AIDS in Dehong were collected from " Chinese National Comprehensive HIV/AIDS and Care Information System" in December, 2014. Results: There were 987 IDUs who should receive MMT, the majority of them were males (94.6%, 934/987), aged 35-44 years (53.0%, 523/987) and farmers (77.2%, 762/987). Among the 987 IDUs, 60.2% (592/987) received no MMT. Multivariate logistic regression analysis showed that being female (OR=2.66, 95%CI: 1.21-5.87), in Jingpo ethnic group (OR=3.05, 95% CI: 1.97-4.71) were the major risk factors for receiving no MMT; not being farmers (OR=0.46, 95%CI: 0.31-0.70), in Dai ethnic group (OR=0.53, 95%CI: 0.36-0.79), diagnosed HIV infection history ≥10 years (OR=0.60, 95%CI: 0.45-0.81) were the major protective factors for receiving no MMT. The reasons for receiving no MMT included long distance journey (289, 48.8%), fear of exposure (124, 20.9%), poor daily medication compliance (59, 10.0%), fear of side effects (47, 7.9%), others (73, 12.3%). Conclusions: The proportion of receiving no MMT in IDUs with AIDS in Dehong was high. Being female and farmer, in Jingpo ethnic group, low educational level, short diagnosed HIV infection history were influencing factors for receiving no MMT. The effective intervention measures should be taken to further improve MMT coverage according to the different characteristics of the patients.
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Affiliation(s)
- R H Tang
- Dehong Prefecture Center for Disease Control and Prevention, Mangshi 678400, China
| | - R H Ye
- Dehong Prefecture Center for Disease Control and Prevention, Mangshi 678400, China
| | - Y C Yang
- Dehong Prefecture Center for Disease Control and Prevention, Mangshi 678400, China
| | - S T Yao
- Dehong Prefecture Center for Disease Control and Prevention, Mangshi 678400, China
| | - J B Wang
- Dehong Prefecture Center for Disease Control and Prevention, Mangshi 678400, China
| | - R M Zhang
- Mangshi County Center for Disease Control and Prevention, Mangshi 678400, China
| | - L F Luo
- Yingjiang County Center for Disease Control and Prevention, Yingjiang 679300, China
| | - Z L Wu
- Ruili County Center for Disease Control and Prevention, Ruili 678600, China
| | - Y C Long
- Longchuan County Center for Disease Control and Prevention, Longchuan 678700, China
| | - M S Yin
- Lianghe County Center for Disease Control and Prevention, Lianghe 679200, China
| | - N He
- Department of Epidemiology, School of Public Health, Fudan University, Shanghai 200032, China
| | - S Duan
- Dehong Prefecture Center for Disease Control and Prevention, Mangshi 678400, China
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Tian Y, Wu ZL, Xu GB, Yang LW, Zhong JX. Hetero-assembly of a Li4Ti5O12 nanosheet and multi-walled carbon nanotube nanocomposite for high-performance lithium and sodium ion batteries. RSC Adv 2017. [DOI: 10.1039/c6ra25651a] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Hetero-assembly of Li4Ti5O12 nanosheets and multi-walled carbon nanotubes for superior Li/Na storage is demonstrated.
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Affiliation(s)
- Y. Tian
- Hunan Key Laboratory of Micro-Nano Energy Materials and Devices
- School of Physics and Optoelectronics
- Xiangtan University
- China
| | - Z. L. Wu
- Hunan Key Laboratory of Micro-Nano Energy Materials and Devices
- School of Physics and Optoelectronics
- Xiangtan University
- China
| | - G. B. Xu
- Hunan Key Laboratory of Micro-Nano Energy Materials and Devices
- School of Physics and Optoelectronics
- Xiangtan University
- China
| | - L. W. Yang
- Hunan Key Laboratory of Micro-Nano Energy Materials and Devices
- School of Physics and Optoelectronics
- Xiangtan University
- China
| | - J. X. Zhong
- Hunan Key Laboratory of Micro-Nano Energy Materials and Devices
- School of Physics and Optoelectronics
- Xiangtan University
- China
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Dahanayaka S, Rezaei R, Porter WW, Johnson GA, Burghardt RC, Bazer FW, Hou YQ, Wu ZL, Wu G. Technical note: Isolation and characterization of porcine mammary epithelial cells. J Anim Sci 2016; 93:5186-93. [PMID: 26641038 DOI: 10.2527/jas.2015-9250] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Within the mammary gland, functional synthesis of milk is performed by its epithelial (alveolar) cells. The availability of a stable mammary epithelial cell line is essential for biochemical studies to elucidate cellular and molecular mechanisms responsible for nutritional regulation of lactation. Therefore, porcine mammary epithelial cells (PMEC) were isolated from mammary glands of a 9-mo-old nonpregnant and nonlactating gilt and cultured to establish a nonimmortalized cell line. These cells were characterized by expression of cytokeratin-18 (an intermediate filament specific for epithelial cells), β-casein (a specific marker for mammary epithelial cells), and α-lactalbumin. In culture, the PMEC doubled in number every 24 h and maintained a cobblestone morphology, typical for cultured epithelial cells, for at least 15 passages. Addition of 0.2 to 2 μg/mL prolactin to culture medium for 3 d induced the production of β-casein and α-lactalbumin by PMEC in a dose-dependent manner. Thus, we have successfully developed a useful PMEC line for future studies of cellular and molecular regulation of milk synthesis by mammary epithelial cells of the sow.
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Deng ZZ, Zhang F, Wu ZL, Yu ZY, Wu G. Chlorpyrifos-induced hormesis in insecticide-resistant and -susceptible Plutella xylostella under normal and high temperatures. Bull Entomol Res 2016; 106:378-386. [PMID: 27241230 DOI: 10.1017/s000748531600002x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Hormesis induced by insecticides at the dosage lower than what ostensibly directly causes death on insects was studied. This paper reports the effects of the in vivo application of varied concentrations of chlorpyrifos (CPF) on Plutella xylostella (DBM). The insecticide concentrations applied included 0.000025-2.5 mg l-1, which are far lower than LC1 (7.2 mg l-1), for the CPF-susceptable (Si) DBM, and 250 mg l-1 which is far below LC1 (1286 mg l-1), for the CPF-resistant (Rc) DBM, as well as LC10- and LC50-doses for both strains. Significant hormesis was found with the 'hermetic-CPFs', i.e., 0.0025 mg l-1 for Si DBM and 2.5 mg l-1 for Rc DBM, at the normal or high temperature either in a 24 h or under a long-term treatment. These doses of CPF significantly stimulated the development and increased the fecundity of Si and Rc DBM at 25°C with approximately 23.5-29.8% activity increase on acetylcholinesterase (AChE) and 30.5-91.3% increase on glutathione S-transferases (GSTs) at 25 or 38°C in 4-24 h. The enzymatic activities were significantly reduced by LC50-CPF at 25°C in vivo, but the inhibition was relieved significantly, if the insects were first subjected to a hormetic-CPF pretreatment. It was remarkable that the average rates of enzymatic activity increase were 67.5-76.6% for AChE and 366-546% for GSTs. Consequently, it was concluded that the hormesis on Si and Rc DBM could be induced by CPF doses far below LC1 at normal or high temperature in short- or long-term treatment. These findings might help to improve the current insect control practices in the field.
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Affiliation(s)
- Z Z Deng
- Key Laboratory of Biopesticide and Chemical Biology (Ministry of Education),Fujian Agriculture and Forestry University,Fuzhou,Fujian 350002,China
| | - F Zhang
- Key Laboratory of Biopesticide and Chemical Biology (Ministry of Education),Fujian Agriculture and Forestry University,Fuzhou,Fujian 350002,China
| | - Z L Wu
- Key Laboratory of Biopesticide and Chemical Biology (Ministry of Education),Fujian Agriculture and Forestry University,Fuzhou,Fujian 350002,China
| | - Z Y Yu
- Key Laboratory of Biopesticide and Chemical Biology (Ministry of Education),Fujian Agriculture and Forestry University,Fuzhou,Fujian 350002,China
| | - G Wu
- Key Laboratory of Biopesticide and Chemical Biology (Ministry of Education),Fujian Agriculture and Forestry University,Fuzhou,Fujian 350002,China
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Wu ZL, Fang YL, Tang YT, Xiao MW, Ye J, Li GX, Hu AX. Synthesis and antitumor evaluation of 5-(benzo[d][1,3]dioxol-5-ylmethyl)-4-(tert-butyl)-N-arylthiazol-2-amines. Med Chem Commun 2016. [DOI: 10.1039/c6md00234j] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The strategy for designing target compounds as antitumor agents.
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Affiliation(s)
- Z. L. Wu
- College of Chemistry and Chemical Engineering
- Hunan University
- Changsha
- China
| | - Y. L. Fang
- College of Chemistry and Chemical Engineering
- Hunan University
- Changsha
- China
| | - Y. T. Tang
- College of Chemistry and Chemical Engineering
- Hunan University
- Changsha
- China
| | - M. W. Xiao
- College of Chemistry and Chemical Engineering
- Hunan University
- Changsha
- China
| | - J. Ye
- College of Chemistry and Chemical Engineering
- Hunan University
- Changsha
- China
| | - G. X. Li
- College of Chemistry and Chemical Engineering
- Hunan University
- Changsha
- China
| | - A. X. Hu
- College of Chemistry and Chemical Engineering
- Hunan University
- Changsha
- China
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Yan LS, Jiang W, Duan WJ, Zheng D, Wu ZL, Guo WF, Wang YS. Morphology variation and optical properties of ZnO nanostructures grown using bio-template. J Nanosci Nanotechnol 2013; 13:1304-1308. [PMID: 23646625 DOI: 10.1166/jnn.2013.5984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
ZnO nanostructures of different morphologies were grown by immersing eggshell membranes into Zn(NO3)2 ethanol solution with different pH values and subsequently sintered at 500 degrees C. Effects of the solution pH value, immersing time and Mg incorporation on the nanostructure morphology and photoluminescence were studied. ZnO nanostructure morphology was very sensitive to pH value of the solution, immersing time and layer of the templates. Different morphologies of nanofibers, nanotubes, hexagonal nanosheets and hexagonal nanosheets with tips were grown. All nanostructures had strong green emission at 520 nm and weak ultraviolet emission at 377 nm. The green emission weakened in the interwoven nanofibers while the ultraviolet emission enhanced in the hexagonal nanosheets. Incorporation of Mg ions in the solution with a pH of 7 would result in combination of the interwoven nanofibers and enhance the green emission greatly. UV emission at 355 nm from ZnMgO alloys was observed in Mg incorporated nanofibers.
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Affiliation(s)
- L S Yan
- Department of Physics, Beijing Normal University, Beijing 100875, China
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Zhang HH, Tian JS, Zhang YM, Wu ZL, Kong XJ, Chao JY, Hu Y, Li DL. Removal of phosphorus and nitrogen from domestic wastewater using a mineralized refuse-based bioreactor. Environ Technol 2012; 33:173-181. [PMID: 22519101 DOI: 10.1080/09593330.2011.555420] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Municipal solid waste used for landfill becomes stabilized, or aged, some years after placement, and can be safely excavated; the term 'mineralized refuse' is used in this study. The adsorptions of phosphorus, and the nitrification of the mineralized refuse and clay, were investigated by batch incubation. The variation of phosphorus adsorption in the mineralized refuse was fitted to the Freundlich adsorption isotherm equation, giving a maximum phosphorus adsorption capacity of 2310 mg kg(-1). Based on the Langmuir isotherm equation, maximum phosphorus adsorption capacity was calculated to be 1976 mg kg(-1), almost twice that of the clay. The equations for both the mineralized refuse and clay were fitted to zero-order kinetics (R2 > 0.98, P < 0.01, n = 11), giving concentrations of phosphorus as phosphates less than 250 mg L(-1). The K value for the mineralized refuse was about 3.5 times higher than for the clay. The production of nitrogen as nitrates in both the mineralized refuse and the clay after 120 h incubation yielded a first-order reaction kinetics value of 100 mg kg(-1) NH4(+)-N from the initial concentration. The calculated net nitrification as nitrates for the mineralized refuse was 6.3 times higher than for the clay. Domestic wastewater was then treated in a mineralized refuse-based bioreactor for 30 days. The removal rates of COD(cr), total nitrogen and total phosphorus were 73.77 +/- 8.10%, 61.01 +/- 6.75%, and 69.14 +/- 9.25%, respectively. Large accumulations of nitrates occurred in the mineralized refuse-based bioreactor. For the full-scale design, a high column of mineralized refuse is recommended for the denitrification.
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Affiliation(s)
- H H Zhang
- Nanjing Institute of Environmental Sciences, China Ministry of Environmental Protection, Nanjing, PR. China.
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Wang YS, Duan WJ, Wu ZL, Dai LJ, Zhou BY, Chen BK, Zhang X. Stability and nonlinear optical properties of ZnO nanoparticles. J Nanosci Nanotechnol 2011; 11:9877-9882. [PMID: 22413313 DOI: 10.1166/jnn.2011.5223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Photoluminescence (PL) of ZnO nanoparticles of different surface states and sizes grown by several methods has been measured. The origin of luminescence and dependence of the luminescence spectrum shape and intensity on 325 nm excitation laser power are studied. Strong ultraviolet emission at 3.26 eV, weak violet emission around 3.12 eV and weak green emission at 2.40 eV have been observed in 16 nm nanoparticles capped by octylamine grown by non-hydrolytic method. The nanoparticles are stable under high power laser radiation and their PL intensity increases nonlinearly with an increasing laser power. As the nanoparticle size decreases to 12 nm, high power laser produces nonradiative centers which may quench the luminescence in a degree. Nanoparticles of 8 nm capped by PVP and uncapped nanoparticles of 14 nm are unstable and their luminescence depends on the excitation laser power. High power laser can quench O vacancy emission and enhance ultraviolet emission in PVP capped nanoparticles while vacancy emission can not be quenched in uncapped nanoparticles.
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Affiliation(s)
- Y S Wang
- Department of Physics, Beijing Normal University, Beijing 100875, China
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Duan WJ, Zhou H, Yang HC, Wu ZL, Zheng D, Wang YS. Growth and properties of ZnO/Zn(1-x)MgxO core/shell nanoparticles. J Nanosci Nanotechnol 2011; 11:9871-9876. [PMID: 22413312 DOI: 10.1166/jnn.2011.5222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
ZnO/Zn(0.9)Mg(0.1)O core/shell nanoparticles have been grown by employing metal cupferronate complex as precursors in organic solvents. ZnO cores are grown by quickly injecting their precursor at 250 degrees C while the shells are performed by slowly injecting their precursors at different temperatures. The grown nanoparticles are characterized by X-ray diffraction, photoluminescence microscopy, and transmission electron microscopy. The effects of the shell growth temperatures and precursor injecting rate are studied. Zn(0.9)Mg(0.1)O shells can epitaxially grow on ZnO cores when the shell growth temperature is lowered to 200 degrees C and the shell precursor is supplied slowly at a rate of 0.1 mmol/h. Increaseing shell supply rate or shell growth temperature results in homogenous growth of Zn(0.9)Mg(0.1)O nanoparticles. The shell growth can dramatically enhance core emission and cause a red shift on the core band edge emission.
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Affiliation(s)
- W J Duan
- Department of Physics, Beijing Normal University, Beijing 100875, China
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Zhou H, Duan WJ, Yang HC, Wu ZL, Wang YS. Growth and properties of Zn(1-x)CdxO and Zn(1-x)CdxO/ZnO core/shell nanoparticles. J Nanosci Nanotechnol 2011; 11:9865-9870. [PMID: 22413311 DOI: 10.1166/jnn.2011.5221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Octylamine capped Zn(1-x)CdxO alloys and Zn(1-x)CdxO/ZnO core/shell nanoparticles have been grown by the thermal decomposing of zinc and cadmium cupferronates in organic solvents. Zn(1-x)CdxO alloys incorprated with different concentration of Cd have been grown by quickly injecting of their precursors at 200 degrees C. Zn(1-x)CdxO/ZnO core/shell nanoparticles are performed by slowly injecting of shell precursors at 180 degrees C. The prepared nanoparticles are characterized by X-ray diffraction, absorption spectrometer, Mirco-Raman spectrometer and transmission electron microscopy. The band gap of ZnCdO alloys shrinks linearly and the crystal lattice expands with an increase of Cd concentration. The growth of ZnO shells on ZnCdO cores enhances the core luminescence dramatically and results in a red shift in the absorption and emission of Zn(1-x)CdxO cores.
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Affiliation(s)
- H Zhou
- Department of Physics, Beijing Normal University, Beijing 100875, China
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Wu ZL, Zheng SS, Li ZM, Qiao YY, Aau MY, Yu Q. Polycomb protein EZH2 regulates E2F1-dependent apoptosis through epigenetically modulating Bim expression. Cell Death Differ 2009; 17:801-10. [PMID: 19893569 DOI: 10.1038/cdd.2009.162] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Deregulation of the pRB/E2F pathway, which occurs frequently in human malignancy, is often associated with inappropriate proliferation and/or apoptosis. While the role of E2F1 in apoptosis induction has been well-established, it remains unclear how this pro-apoptotic activity is regulated in cancer. Here we describe EZH2, an oncogenic polycomb histone methyltransferase and an E2F1 target, as an important regulator of E2F1-dependent apoptosis. We show that E2F1 induces EZH2 expression, which in turn antagonizes the induction of E2F1 pro-apoptotic target Bim expression. RNAi-mediated gene depletion of EZH2 enhances E2F1-dependent Bim expression, thereby promoting the pro-apoptotic activity of E2F1. Hence, the concomitant induction of EZH2 and Bim by E2F1 constitutes a fail-safe mechanism to allow tumor cells with aberrant E2F1 activity to evade apoptosis. These findings reveal a novel mechanism by which the apoptotic activity of E2F1 is restrained in human cancer and also provide the first evidence that EZH2 directly regulates apoptotic process in cancer cells.
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Affiliation(s)
- Z L Wu
- Genome Institute of Singapore, Biopolis, Singapore
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15
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Wang ZG, Lee C, Waltzer W, Yuan ZJ, Wu ZL, Xie HK, Pan YT. Optical coherence tomography for noninvasive diagnosis of epithelial cancers. Conf Proc IEEE Eng Med Biol Soc 2008; 2006:129-32. [PMID: 17946790 DOI: 10.1109/iembs.2006.259452] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We summarize our recent progress in the development of the optical coherence tomography (OCT) systems suitable for clinical diagnosis and the preliminary results for in vivo diagnosis of epithelial cancers (e.g., bladder cancers). The endoscopic spectral-domain OCT system allows simultaneous, real-time, cross-sectional OCT images of tissue structure and functions (i.e., local Doppler blood flow) of biological tissue for enhanced diagnosis. A new approach to use spectral demodulation of elastic scattering is discussed for potential cancer grading. The transverse and axial resolutions of the OCT scopes are 12 microm and 10 microm, respectively. Results of the preliminary clinical studies show that unlike animal carcinogenesis models, bladder cancers in humans are more complicated in terms of epithelial backscattering changes: some lesions exhibit enhanced backscattering; some show reduced scattering owing to complex surface condition changes such as asperities or invaginations induced by tumorigenesis (e.g., papillary transitional cell cancers). Nevertheless, promising results can be provided by incorporating other diagnostic parameters such as changes in local vasculature and urothelial heterogeneity.
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Affiliation(s)
- Z G Wang
- Dept. of Biomedical Engineering, State University of New York at Stony Brook, NY 11794-8181, USA
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16
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Qiao L, Wu ZL, Pan YX. [A case with subdural hydrops caused by cerebral cysticercosis]. Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi 2003; 18:4. [PMID: 12567459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
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17
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Lei YX, Chen JK, Wu ZL. Detection of DNA strand breaks, DNA-protein crosslinks, and telomerase activity in nickel-transformed BALB/c-3T3 cells. Teratog Carcinog Mutagen 2002; 21:463-71. [PMID: 11746259 DOI: 10.1002/tcm.1033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Although nickel compounds are known carcinogens, the underlying carcinogenic mechanisms are not fully understood. The objective of this research was to determine if the genotoxic lesions of DNA strand breaks and DNA-protein crosslinks are present in nickel-transformed BALB/c-3T3 cells, and to further elucidate the potential carcinogenesis of insoluble and soluble nickel compounds through telomerase activity in nickel-transformed BALB/c-3T3 cell lines. DNA strand breaks, DNA-protein crosslinks and telomerase activity were investigated by single cell gel electrophoresis (comet assay), (125)I-postlabelling techniques, and the TRAP-silver staining assay, respectively. Results showed that both DNA strand breaks and DNA-protein crosslinks were present in nickel-transformed BALB/c-3T3 cells. However, the highest levels of DNA strand breaks and DNA-protein crosslinks were found in insoluble crystalline NiS-transformed cells and high levels of DNA strand breaks and DNA-protein crosslinks were also found in the transformed cells induced by two water-soluble NiCl(2) and NiSO(4) at moderate concentrations of cytotoxicity. These data suggest that these two genetic endpoints are useful biomarkers and are associated with cell transformation and carcinogensis of insoluble and soluble nickel compounds. Also, we found that the crystalline NiS- and NiCl(2)-transformed cells possessed a high telomerase activity. A weak telomerase was found in NiSO(4)-transformed cells. The results seem to indicate that in addition to crystalline NiS, some water-soluble nickel compounds such as NiCl(2) are also highly carcinogenic. These results may partly explain the cell transformation and relative carcinogenic potency of insoluble crystalline NiS, soluble NiCl(2), and NiSO(4).
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Affiliation(s)
- Y X Lei
- Institute for Chemical Carcinogenesis, Guangzhou Medical College, Guangzhou, People's Republic of China.
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18
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Bozyczko-Coyne D, O'Kane TM, Wu ZL, Dobrzanski P, Murthy S, Vaught JL, Scott RW. CEP-1347/KT-7515, an inhibitor of SAPK/JNK pathway activation, promotes survival and blocks multiple events associated with Abeta-induced cortical neuron apoptosis. J Neurochem 2001; 77:849-63. [PMID: 11331414 DOI: 10.1046/j.1471-4159.2001.00294.x] [Citation(s) in RCA: 127] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Although the mechanism of neuronal death in Alzheimer's disease (AD) has yet to be elucidated, a putative role for c-jun in this process has emerged. Thus, it was of interest to delineate signal transduction pathway(s) which regulate the transcriptional activity of c-jun, and relate these to alternate gene inductions and biochemical processes associated with beta-amyloid (Abeta) treatment. In this regard, the survival promoting activity of CEP-1347, an inhibitor of the stress-activated/c-jun N-terminal (SAPK/JNK) kinase pathway, was evaluated against Abeta-induced cortical neuron death in vitro. Moreover, CEP-1347 was used as a pharmacologic probe to associate multiple biochemical events with Abeta-induced activation of the SAPK/JNK pathway. CEP-1347 promoted survival and blocked Abeta-induced activation of JNK kinase (MKK4, also known as MEK-4, JNKK and SEK1) as well as other downstream events associated with JNK pathway activation. CEP-1347 also blocked Abeta-induction of cyclin D1 and DP5 genes and blocked Abeta-induced increases in cytoplasmic cytochrome c, caspase 3-like activity and calpain activation. The critical time window for cell death blockade by CEP-1347 resided within the peak of Abeta-induced MKK4 activation, thus defining this point as the most upstream event correlated to its survival-promoting activity. Together, these data link the SAPK/JNK pathway and multiple biochemical events associated with Abeta-induced neuronal death and further delineate the point of CEP-1347 interception within this signal transduction cascade.
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19
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Wu ZL, Wang AQ. Diagnostic yield of repeated smear microscopy examinations among patients suspected of pulmonary TB in Shandong province of China. Int J Tuberc Lung Dis 2000; 4:1086-7. [PMID: 11092724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
OBJECTIVES To analyse the yield of five repeated smear microscopy examinations for the diagnosis of smear-positive pulmonary tuberculosis (TB). METHODS Patients with respiratory symptoms and abnormal chest X-rays provided five spontaneous sputum samples for acid-fast bacilli (AFB) smear microscopy in one of nine county laboratories. RESULTS Of 9302 patients with respiratory symptoms and abnormal X-rays, 6437 (69%) had at least one smear-positive sputum. Of these, 84.5% were diagnosed on the first smear, 96.7% on the first two smears, and 99.9% on the first three sputum smears. The fourth and fifth sputum smears yielded only seven additional cases (0.1%). CONCLUSIONS Smear microscopy examination of two spontaneous sputum specimens is the most efficient, and three sputum smear examinations provide a diagnosis in almost all cases.
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Affiliation(s)
- Z L Wu
- Shandong Center for Tuberculosis Control, Jinan, China.
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20
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Wu ZL, Di JS, Yuan YJ, Hu ZD. [Study on taxol release in the two-liquid-phase cultures of Taxus cuspidata]. Sheng Wu Gong Cheng Xue Bao 2000; 16:500-4. [PMID: 11051828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Effects of rare earth compound (ammonium sulphate), organic solvents(oleic acid and dibutylphthalate) and the integrated function of the rare earth compound and organic solvents were studied on taxol release in the Taxus cuspidata suspension cultures. And then effects of different organic solvents(paraffin, organic acid, alcohol and ester), their volumetric fraction and phase toxicity were studied on taxol release in the two-liquid-phase cultures of Taxus cuspidata. The results showed that the addition of the rare earth compound or the organic solvents could strengthen obviously taxol release, especially the organic solvents. But the addition of the rare earth compound could not strengthen further taxol release in the twoliquid-phase cultures of Taxus cuspidata. Therefore the organic solvents were very good permeabilizing reagents, which could enhance obviously secondary metabolite in the twoliquid-phase cultures of plant cells. Release percentage of taxol was increased into more than 75% from 40% of the control.
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Affiliation(s)
- Z L Wu
- Department of Bioengineering, Hebei University of Technology, Tianjin
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21
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Abstract
The effect of diethylstilbestrol (DES) on urethan-induced mouse lung tumorigenesis was assessed by a single intraperitoneal injecting of urethan (50 mg/kg) or/and multi intramuscular injecting of DES (5 or 50 mg/kg). All mice were sacrificed 18 weeks after administration, and the lung tumors were examined histopathologically. DES did not produce an elevated lung tumor response when administered alone, but it produced a statistically significant enhancement of incidence of tumors, average number of tumors, incidence of cancers and constituent ratio of malignant tumors when given in conjunction with urethan. The results indicated that DES may be a promoter in lung tumor formation.
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Affiliation(s)
- Y G Jiang
- Institute for Chemical Carcinogenesis, Guangzhou Medical College, People's Republic of China
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22
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Abstract
In order to explore the damage from metabolites of benzo(a)pyrene on DNA of mammalian cells, the effects of four metabolites of benzo(a)pyrene (anti-BPDE, syn-BPDE, 3-OH-BP and 9-OH-BP) on synthesis of DNA and unschedule DNA synthesis (UDS) in BALB/3T3 cells were assayed, by methods of single-labeling and double-labeling. The results showed that all of the four agents were able to increase the synthesis of DNA, but only three of them (apart from syn-BPDE) induced UDS in BALB/3T3 cells. The above indicates that the metabolites of benzo(a)pyrene are able to damage DNA in BALB/3T3 cells, and that this effect may be relative to the sterical structure of metabolites of benzo(a)pyrene.
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Affiliation(s)
- J K Chen
- Institute for Chemical Carcinogenesis, Guangzhou Medical College, People's Republic of China
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Abstract
A modified photothermal deformation technique is used to measure the absorptance behaviors of optical multilayered dielectric coatings for a high-power laser system. The surface thermal-lensing modification uses an enlarged probe beam to facilitate alignment of the laser beam and data acquisition. The coatings, both reflective and transmissive types, are made by a physical vapor-deposition process. Coating absorptances are observed to depend on the laser's exposure time and power density. Time-dependent absorptance defect models are proposed. Also, micrometer-sized sites of high absorptance and an area with physical damage can be found during the spatial scans. It is proposed that absorptance values reported for coatings in high-repetition-rate or cw-laser systems include time- and power-dependent behaviors in addition to other relevant irradiation parameters.
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Affiliation(s)
- R Chow
- Lawrence Livermore National Laboratory, University of California, Livermore, California 94550, USA.
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Beagley KW, Wu ZL, Pomering M, Jones RC. Immune responses in the epididymis: implications for immunocontraception. J Reprod Fertil Suppl 2000; 53:235-45. [PMID: 10645283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
In recent years the need to develop vaccines against a variety of sexually transmitted diseases, the desire to treat male infertility and interest in developing alternative contraceptive methods have focused research interest on the immunology of the male reproductive tract. This paper reviews the current state of knowledge of immunity in the male tract. Both physical and immune mechanisms that operate to maintain the blood-testis barrier are discussed with regard to (i) their importance in preventing autoimmune responses against spermatozoa and (ii) how these can be overcome to induce specific immunity in the testis and efferent ducts. The role of both the systemic and mucosal arms of the humoral immune response are discussed both in terms of immune-mediated infertility and the induction of specific immunity. Finally some novel approaches to elicit immunity in the male reproductive tract are discussed.
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Affiliation(s)
- K W Beagley
- Discipline of Pathology, Faculty of Medicine and Health Sciences, University of Newcastle, Callaghan, NSW, Australia
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25
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Abstract
Background: Renal vein thrombosis (RVT) complicating the nephrotic syndrome is associated with a poor prognosis. Methods/Results: RVT was diagnosed in 12 of 60 patients with a diagnosis of nephrotic syndrome suggested by computed tomography (CT) and subsequently confirmed by selective renal angiography. Fifty patients carried a diagnosis of primary glomerulonephritis with various pathological findings, and 10 patients had lupus nephritis. Renal vein and peripheral vein blood samples were collected in the 12 patients with RVT and were assayed for fibrin(ogen) degradation products (FDP), antithrombin III (AT III), VIIIR:AG, and fibrinogen. The results suggested a state of hypercoagulation. Of these 12 patients, 7 were given 200,000 units of urokinase (UK) over 60 minutes in divided doses selectively via the renal vein. Five patients were given 200,000 units UK selectively into the renal artery. All patients also received 2.5 mg/day warfarin and 75 mg/day persantine. Except for three patients with focal glomerulosclerosis, all patients received 40 mg/day prednisone. After 1 month, the CT scan and blood samples for FDP, AT III, VIIIR:AG, and fibrinogen were repeated. Patients receiving intra-arterial UK had complete resolution of their thrombi. Complete resolution was also suggested in 2 of the 7 patients receiving UK by renal vein, and there was partial resolution in the other five. The hyper-coagulation state decreased in all patients. Conclusions: We conclude that RVT is not an uncommon event in patients with nephrotic syndrome. The diagnosis can be supported reliably using abdominal CT scanning. Although a small number of patients were included in this nonrandomized study, it appeared that intra-arterial thrombolytic therapy yielded better results. The patients with minimal change disease have a good prognosis.
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Affiliation(s)
- ZL Wu
- Zhong Shan Hospital, Shanghai Medical University, Shanghai, China
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26
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Abstract
A rat model of hypercatabolic acute renal failure (ARF) was developed in order to further investigate the mechanism of this condition. Sprague Dawley rats were separated into three groups: a septicemic group, an ischemic ARF group, and a hypercatabolic ARF group. Septicemia was produced by the i.p. injection of 1 x 10(7) colony-forming units/mL of Escherichia coli. Ischemic ARF was induced by 60 minutes clamping of the left renal artery following a contralateral nephrectomy. Hypercatabolic ARF was produced by combining ischemic ARF with the i.p. injection of 1 x 10(7) colony-forming units/mL of Escherichia coli. The hypercatabolic ARF group exhibited septic clinical features after the surgical procedures. The blood urea nitrogen and the serum creatinine, potassium and carbon dioxide combining power of hypercatabolic ARF were significantly higher than other two groups 24 hours after surgery. In addition, the rats wit hypercatabolic ARF had a greater loss of body weight and a higher mortality rate compared to the other two groups. The features of this form of experimental ARF are similar to the clinical characteristics of hypercatabolic ARF. Consequently, this appears to be a useful model of hypercatabolic ARF.
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Affiliation(s)
- Z L Wu
- Department of Nephrology, Zhong Shan Hospital, Shanghai Medical University, P.R. China
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27
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Ge YQ, Wu ZL, Xu YZ, Liao LT. Study on nutritional status of maintenance hemodialysis patients. Clin Nephrol 1998; 50:309-14. [PMID: 9840319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
The nutritional status of 75 maintenance hemodialysis (MHD) patients was evaluated according to the dietary intake analysis, anthropometric measurements, biochemical and immunological parameters in this study. Furthermore, some possible factors which would affect nutritional status of hemodialysis patients were discussed. The results showed that hemodialysis patients demonstrated a high incidence of malnutrition. The low intake of protein and calorie, metabolic acidosis and inadequate dialysis would worsen the malnutrition while erythropoietin treatment improve the nutritional status of hemodialysis patients. Based on these results, suggestions were proposed for the improvement of nutritional status of MHD.
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Affiliation(s)
- Y Q Ge
- Department of Nephrology, Zhong Shan Hospital, Shanghai Medical University, China
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28
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Misra A, Wu ZL, Kush MT, Gibala R. Deformation and fracture behaviour of directionally solidified NiAl-Mo and NiAl-Mo(Re) eutectic composites. ACTA ACUST UNITED AC 1998. [DOI: 10.1080/01418619808241921] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Wu ZL, Huang SL, Ou-Yang DS, Xu ZH, Xie HG, Zhou HH. Clomipramine N-demethylation metabolism in human liver microsomes. Zhongguo Yao Li Xue Bao 1998; 19:433-6. [PMID: 10375803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
AIM To study the effect of cytochrome P-450 (CYP450) inhibitors on clomipramine (Clo) N-demethylation in vitro. METHODS The kinetic parameters of Clo N-demethylation in human liver microsomes were obtained by the Michaelis-Menten equation. The parameters after pretreatment with putative inhibitors of various CYP450 isoforms were compared with controls. RESULTS K(m1), K(m2), Vmax1, Vmax2, Vmax1/K(m1), and Vmax2/K(m2) were (0.11 +/- 0.06), (24 +/- 14) mumol.L-1, (114 +/- 47), (428 +/- 188) nmol.g-1.min-1, (1.8 +/- 1.6), and (0.019 +/- 0.005) L.g-1.min-1, respectively. The interindividual variations for the last 4 parameters reached up to 2.5-, 7.3-, 3.4-, and 1.8-fold. At 5 mumol.L-1 of Clo, troleandomycin (Tro), furafylline (Fur), ditiocarb sodium (Dit), and S-mephenytoin (Mep) produced a marked inhibition on Clo N-demethylation while sulfaphenazole (Sul) and quinidine (Qui) had only slight effects. The inhibitory rates by Dit 30, Mep 500, Fur 10, Tro 10, Fur 80, Tro 200 and Fur 80 + Tro 200 mumol.L-1 were 27.0%, 32.9%, 42.8%, 40.5%, 63.9%, 66.4%, and 78.3%, respectively. The IC50 (95% confidence limits) for Fur and Tro were 27.7 (19.1-36.3) and 42.1 (20.9-63.3) mumol.L-1, respectively. CONCLUSIONS The N-demethylation of Clo exhibited a biphasic behavior. This reaction was mediated mainly by both CYP1A2 and CYP3A4, to a minor extent by CYP2C19 at the low concentration of Clo in vitro.
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Affiliation(s)
- Z L Wu
- Pharmacogenetics Research Institute, Hunan Medical University, Changsha, China.
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30
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Abstract
Recently, the close relation between oxidized low density lipoprotein (Ox-LDL) and the progression of glomerular injury has been demonstrated. The nitric oxide (NO) pathway in glomerular mesangial cells may be a potential target for the adverse effects of Ox-LDL in the development of glomerular injury. In this study, we treated cultured rat mesangial cells (RMC) with Fe(2+)-oxidized LDL and then stimulated the cells with lipopolysacharride (LPS, 10 micrograms ml-1). The LPS-induced NO production, assessed by NO2-concentrations in cultured supernatants, decreased from 7.83 nmol per 10(6) cells in control to 4.00 nmol per 10(6) cells and 1.67 nmol per 10(6) cells in RMC preincubated with Ox-LDL at 20 micrograms ml-1 and 40 micrograms ml-1, respectively (P < 0.01). Native LDL had no significant effects on LPS-induced NO production. Using the reverse transcription-polymerase chain reaction (RT-PCR) technique, we could not detect significant alteration of inducible NO synthase (iNOS) mRNA levels in RMC preincubated with Ox-LDL. Our results suggest that Ox-LDL decreases induced NO production in RMC, which may contribute to the adverse effects of Ox-LDL in progressive glomerular injury. The mechanisms of this decrease may not involve changes of iNOS genic transcription.
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Affiliation(s)
- Z L Wu
- Division of Nephrology, Zhong Shan Hospital, Shanghai, P.R. China
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31
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Xu X, Ng S, Wu ZL, Nguyen D, Homburger S, Seidel-Dugan C, Ebens A, Luo Y. Human semaphorin K1 is glycosylphosphatidylinositol-linked and defines a new subfamily of viral-related semaphorins. J Biol Chem 1998; 273:22428-34. [PMID: 9712866 DOI: 10.1074/jbc.273.35.22428] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The semaphorin family contains a large number of secreted and transmembrane proteins, some of which are known to act as repulsive axon guidance cues during development or to be involved in immune function. We report here on the identification of semaphorin K1 (sema K1), the first semaphorin known to be associated with cell surfaces via a glycosylphosphatidylinositol linkage. Sema K1 is highly homologous to a viral semaphorin and can interact with specific immune cells, suggesting that like its viral counterpart, sema K1 could play an important role in regulating immune function. Sema K1 does not bind to neuropilin-1 or neuropilin-2, the two receptors implicated in mediating the repulsive action of several secreted semaphorins, and thus it likely acts through a novel receptor. In contrast to most previously described semaphorins, sema K1 is only weakly expressed during development but is present at high levels in postnatal and adult tissues, particularly brain and spinal cord.
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Affiliation(s)
- X Xu
- Exelixis Pharmaceuticals, Inc., South San Francisco, California 94080, USA
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32
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Liu YG, Wu ZL, Chen JK. Differential effects of aneugens and clastogens on incidences of multinucleated cells and of micronucleate cells in Chinese hamster lung (V79) cell line in vitro. Mutat Res 1998; 413:39-45. [PMID: 9602857 DOI: 10.1016/s1383-5718(98)00012-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Two aneugens, vinblastine (0.025-0.4 microgram/ml) and colchicine (0.05-0.4 microgram/ml), and two clastogens, mitomycin C (0.05-0.4 microgram/ml) and cyclophosphamide (1-16 micrograms/ml) were applied respectively to the micronucleus test in Chinese hamster lung (V79) cells in vitro, and the frequency of multinucleated cells (Fmu) and that of micronucleate cells (Fmi) in each group were observed. The results showed that at relatively high concentrations, all four agents increased both Fmu and Fmi, but the ratios of Fmu to Fmi in groups of the two aneugens (average of 2.2, 2.8, respectively) were much (10-30 folds) higher than that in groups of the two clastogens (0.09, 0.20). The difference between aneugens and clastogens in the above ratio was much more remarkable than that in areas of micronuclei (only 1.6-2.5 folds for the latter). At relatively low concentrations, the two clastogens increased only Fmi (but not Fmu), while the two aneugens increased only Fmu (but not Fmi). This indicates that the induction of multinuclei by aneugens may be more sensitive than by clastogens, and the induction of micronuclei by clastogens may be more sensitive than by aneugens. So, it is possible for the ratio of Fmu to Fmi to become a simple and sensitive (though indirect) index for distinguishing aneugens from clastogens. Further studies with other mutagens and (or) other cell types will be needed to confirm the deduction. As no difference in frequency of polyploid cells was observed between control group and each treatment, the multinucleation does not seem related to endoreduplication of chromosomes.
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Affiliation(s)
- Y G Liu
- Institute for Chemical Carcinogenesis, Guangzhou Medical College, China
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Ong TM, Song B, Qian HW, Wu ZL, Whong WZ. Detection of genomic instability in lung cancer tissues by random amplified polymorphic DNA analysis. Carcinogenesis 1998; 19:233-5. [PMID: 9472718 DOI: 10.1093/carcin/19.1.233] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Genomic instability resulting in multiple mutations is believed to be a driving force in the carcinogenic process. In this study, the random amplified polymorphic DNA (RAPD) technique, a simple PCR-based DNA polymorphism assay system, was used for detecting genomic instability in lung cancer tissues. DNAs from 20 lung cancer (18 non-small cell lung cancers and two small cell lung cancers) and their corresponding normal tissues were amplified individually by RAPD with seven different 10-base arbitrary primers. PCR products from RAPD were electrophoretically separated in agarose gels and banding profiles were visualized by ethidium bromide staining. The ability to detect genomic instability in 20 cancer tissues by each single primer ranged from 15 to 75%. DNA changes were detected by at least one primer in 19 (95%) cancer tissues. These results seem to indicate that genomic rearrangement is associated with lung carcinogenesis and that RAPD analysis is useful for the detection of genomic instability in lung cancer tissues.
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Affiliation(s)
- T M Ong
- Toxicology and Molecular Biology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV 26505, USA.
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Gordon AS, Yao L, Wu ZL, Coe IR, Diamond I. Ethanol alters the subcellular localization of delta- and epsilon protein kinase C in NG108-15 cells. Mol Pharmacol 1997; 52:554-9. [PMID: 9380017 DOI: 10.1124/mol.52.4.554] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Protein kinase C (PKC) has been shown to regulate the ethanol sensitivity of membrane-bound receptors and transporters, but little is known about the molecular mechanisms underlying this regulation. PKC is a family of isozymes that translocate to new intracellular sites on activation. Here we present immunochemical data showing that ethanol causes translocation of delta- and epsilon-PKC to new intracellular sites. Ethanol causes translocation of delta-PKC from the Golgi to the perinucleus; this translocation is similar to that induced by activation of PKC with phorbol esters. In contrast, epsilon-PKC translocation caused by ethanol is different from that induced by phorbol esters; ethanol causes translocation of epsilon-PKC from the perinucleus to the cytoplasm, whereas phorbol ester activation causes translocation of epsilon-PKC to the nucleus. Because the substrate specificity of these kinases is determined by their site of localization, ethanol-induced translocation of delta- and epsilon-PKC to new intracellular sites may explain some of the pleiotropic effects of ethanol on cellular functions.
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Affiliation(s)
- A S Gordon
- Ernest Gallo Clinic and Research Center and Department of Neurology, University of California, San Francisco, California 94110, USA
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Wu ZL, Zeng G. [Drug resistance of the pathogenic organism]. Zhonghua Liu Xing Bing Xue Za Zhi 1997; 18:114-7. [PMID: 9812514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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Thomsen M, Wu ZL. Polarizing and reflective coatings based on half-wave layer pairs. Appl Opt 1997; 36:307-313. [PMID: 18250675 DOI: 10.1364/ao.36.000307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The majority of the layers of a multilayer optical coating typically have optical thicknesses equal to one quarter of the appropriate wavelength of radiation. Replacing this constraint with the stipulation that a pair of adjacent layers should have a total optical thickness of one half of a wavelength introduces a significant new component of design flexibility while having a minimal impact upon the desired optical properties of the film. Taking a matrix approach, we derive a general expression for the reflectance of a periodic thin-film structure that is based on layers of two different materials of arbitrary thickness. This result is applied to highly reflective coatings at normal incidence and to off-normal polarizing coatings. Specific results involving HfO(2)/SiO(2) films and TiO(2)/SiO(2) films are displayed. We discuss how the thickness of the high-index layers may be reduced to increase damage thresholds. We also show a mirror design that is effective not only at lambda = 1.06 mum but also at the frequency-doubled wavelength.
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Wu ZL, Wang JP, Pan WK, Zhu JR, Guo MY, Liao LT. The presentation, treatment and outcome of acute glomerulonephritis in the elderly. Clin Nephrol 1996; 45:277-9. [PMID: 8861806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
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Wu ZL, Zhang WC, Tan GT. [Application of catalytic model in sero-epidemiology of schistosomiasis]. Zhonghua Liu Xing Bing Xue Za Zhi 1995; 16:270-3. [PMID: 8706092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The seroepidemiological data from two schistosomiasis japonica areas with different transmission levels was analysed using a Catalytic Model. The age-specific distribution of IgG antibody in the population of the two investigated settings was analysed with simple catalytic model, the curve equations are Y(A) = 0.876 (1--e-0.048t) and Y(B) = 5.71 (1--e-0.003t) respectively in the heavy- and mild-endemic areas. The age-specific distribution of IgM antibody was analysed with two-stage catalytic model, using a curve equations Y(A) = 2.13 (e-0.032t--e-0.047t) and Y(B) = 0.19 (e-0.012t--e-0.075t) respectively in both heavy-and mild-endemic areas. Based on the result of stool examination concurrently carried out with sera detection and the endemic situation in recent years, the results mentioned above were eligible for the analysis of seroepidemiological data on schistosomiasis to reveal the endemic situation, tendency and the characteristic of age-specific distribution, and in particular using a two-stage catalytic model to analyse IgM antibody. It could also be used for studies on endemic factors, evaluation on the efficiency of control programmes and for surveillance of endemicy.
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Affiliation(s)
- Z L Wu
- Immunoparasitology Research Center, Zhejiang Medical University, Hangzhou
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Wu ZL, Thomas SA, Villacres EC, Xia Z, Simmons ML, Chavkin C, Palmiter RD, Storm DR. Altered behavior and long-term potentiation in type I adenylyl cyclase mutant mice. Proc Natl Acad Sci U S A 1995; 92:220-4. [PMID: 7816821 PMCID: PMC42849 DOI: 10.1073/pnas.92.1.220] [Citation(s) in RCA: 313] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The murine Ca(2+)-stimulated adenylyl cyclase (type I) (EC 4.6.1.1), which is expressed predominantly in brain, was inactivated by targeted mutagenesis. Ca(2+)-stimulated adenylyl cyclase activity was reduced 40-60% in the hippocampus, neocortex, and cerebellum. Long-term potentiation in the CA1 region of the hippocampus from mutants was perturbed relative to controls. Both the initial slope and maximum extent of changes in synaptic response were reduced. Although mutant mice learned to find a hidden platform in the Morris water task normally, they did not display a preference for the region where the platform had been when it was removed. These results indicate that disruption of the gene for the type I adenylyl cyclase produces changes in behavior and that the cAMP signal transduction pathway may play an important role in synaptic plasticity.
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Affiliation(s)
- Z L Wu
- Department of Pharmacology, Howard Hughes Medical Institute, University of Washington, Seattle 98195
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Wu ZL, Bange K. Comparative photothermal study of reactive low-voltage ion-plated andelectron-beam-evaporated TiO(2) thin films. Appl Opt 1994; 33:7901-7907. [PMID: 20963004 DOI: 10.1364/ao.33.007901] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The thickness-dependent optical and thermal properties and the corresponding damage thresholds have been investigated by means of various photothermal techniques on titanium dioxide thin films prepared by the conventional techniques of reactive electron-beam evaporation and reactive low-voltage ion plating (RLVIP). Compared with the reactive-electron-beam-evaporated samples, the RLVIP films exhibit a higher absorption, lower damage threshold, better thermal conductivity, lower defect density, and an almost perfect stability under Ar(+)-laser irradiation. These results are correlated with data from a multimethod approach, and a mechanism is proposed to explain the low damage threshold for the RLVIP TiO(2) films.
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Wu ZL, Zhou KR, Liao LT. Renal vein thrombosis and refractory nephrotic state. Saudi J Kidney Dis Transpl 1994; 5:498-499. [PMID: 18583779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023] Open
Affiliation(s)
- Z L Wu
- Zhong Shan Hospital, Shanghai Medical University, Shanghai, People′s Republic of China, China
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Wu ZL, Zhou KR, Liao LT. Thrombolytic therapy of renal vein thrombi and follow-up. Clin Nephrol 1994; 42:276-7. [PMID: 7834924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
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Wu ZL, Chen FX, Lai YH. [Mechanism and prevention of hemolysis in jaundiced infants in phototherapy]. Zhonghua Yi Xue Za Zhi 1994; 74:364-6, 391-2. [PMID: 7994648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
It has been reported that the prolonged phototherapy results in decreased glutathione reductase (GR) activity in red blood cells. We found short-term phototherapy had the same side-effect. Besides it aggravates hemolysis of newborns during the therapy. This side-effect can be prevented by oral administration of Vit B2. Eighteen jaundiced infants who were given Vit B2 5mg three times a day during the phototherapy, and the control group of 16 patients were not given Vit B2. The results showed that the decrease of hemoglobin and the time of jaundice disappearance during the phototherapy were more favourable in the oral Vit B2 group than those of the control. These results indicated that the short-term phototherapy not only results in decreased GR activity in red blood cell, but also results in hemolysis of the newborn. This side-effect can be prevented by oral administration of Vit B2.
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Affiliation(s)
- Z L Wu
- Department of Pediatrics, First Affiliated Hospital, Guangzhou Medical College
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Li SH, Fei X, Chen SF, Ding ZQ, Wu ZL. Pentoxifylline attenuates platelet activating factor-induced permeable edema in isolated perfused guinea pig lungs. Zhongguo Yao Li Xue Bao 1994; 15:219-22. [PMID: 7976374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The effect of pentoxifylline (Pen) on platelet activating factor (PAF)-induced pulmonary injury was studied in isolated guinea pig lungs perfused with cell-free Tris buffered Ringer solution. PAF (1.0 nmol.L-1) increased lung weight and pulmonary filtration coefficient (Kf), which indicated the formation of high permeable pulmonary edema. Pen (0.5 and 1.0 mmol.L-1) markedly attenuated the PAF-induced increment of lung weight and vascular permeability, but not the increment of pulmonary capillary pressure and venous resistance. There was no correlation between the severity of lung edema and the number of leukocytes in the perfusates. These results suggest that Pen has direct anti-permeability effect on pulmonary microvessels.
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Affiliation(s)
- S H Li
- Department of Pathophysiology, Second Military Medical University, Shanghai, China
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Abstract
Because chronic iron overload can cause organ injury in hemochromatosis and because iron participates in injury during renal ischemia-reperfusion, the effect of mild subacute renal iron loading on the susceptibility to ischemic acute renal failure was evaluated. Male Sprague-Dawley rats were injected with iron nitrilotriacetate (1 mg iron/kg BW i.p. daily) for 5 days. Controls were instead injected with nitrilotriacetate. Seventy-two hours later animals were subjected to 40-min renal artery ischemia. Iron loading produced a 28% increase in kidney iron content without any change in baseline renal function (plasma creatinine) or histology. Ischemic renal injury was far more severe in iron-loaded animals. Plasma creatinine 24 and 48 h after ischemia was significantly higher in iron-loaded rats (3.3 and 3.4 vs. 2.2 and 0.8 mg/dL) and GFR was significantly lower in iron-loaded rats (0.30 vs. 0.78 mL/min). In addition, iron-loaded rats showed a dramatically greater extent of damage by histologic evaluation using a semiquantitative scoring method. Therefore, a small increase in renal iron content greatly increased renal injury after an ischemic insult. These findings may be relevant to human renal disease because there is accumulating evidence of renal iron accumulation in a variety of proteinuric and chronic renal diseases.
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Affiliation(s)
- Z L Wu
- University of Minnesota, Minneapolis
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Wu ZL, Chen JK, Ong T, Brockman HE, Whong WZ. Antitransforming activity of chlorophyllin against selected carcinogens and complex mixtures. Teratog Carcinog Mutagen 1994; 14:75-81. [PMID: 8066549 DOI: 10.1002/tcm.1770140204] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Chlorophyllin, a derivative of chlorophyll, is known to be an antimutagenic agent. Studies were performed to determine whether chlorophyllin can also inhibit morphological transformation of BALB/3T3 cells induced by carcinogens and complex mixtures. Chlorophyllin was added to the cultures simultaneously with carcinogens or complex mixtures while the transformation assay was conducted. At concentrations that did not significantly affect cell growth, chlorophyllin was found to inhibit morphological transformation induced by N-methyl-N'-nitro-N-nitrosoguanidine, 3-methylcholanthrene, 7,12-dimethylbenz(a)anthracene, benzo(a)pyrene, aflatoxin B1, and extracts of coal dust, tobacco snuff, and chewing tobacco. In all cases, the mean number of transformed foci per flask treated with chlorophyllin was significantly lower than that of untreated cultures. The reduction in the number of transformed foci was dependent on the concentration of chlorophyllin tested. These results indicate that chlorophyllin is an antitransforming agent.
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Affiliation(s)
- Z L Wu
- Division of Respiratory Disease Studies, National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505-2888
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Pan SQ, Charles T, Jin S, Wu ZL, Nester EW. Preformed dimeric state of the sensor protein VirA is involved in plant--Agrobacterium signal transduction. Proc Natl Acad Sci U S A 1993; 90:9939-43. [PMID: 8234338 PMCID: PMC47688 DOI: 10.1073/pnas.90.21.9939] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Plant signal molecules such as acetosyringone and certain monosaccharides induce the expression of Agrobacterium tumefaciens virulence (vir) genes, which are required for the processing, transfer, and possibly integration of a piece of the bacterial plasmid DNA (T-DNA) into the plant genome. Two fo the vir genes, virA and virG, belonging to the bacterial two-component regulatory system family, control the induction of vir genes by plant signals. virA encodes a membrane-bound sensor kinase protein and virG encodes a cytoplasmic regulator protein. Although it is well established from in vitro studies that the signal transduction process involves VirA autophosphorylation and subsequent phosphate transfer to VirG, the structural state of the VirA protein involved in signal transduction is not understood. In this communication, we describe an in vivo crosslinking approach which provides physical evidence that VirA exists as a homodimer in its native configuration. The dimerization of VirA neither requires nor is stimulated by the plant signal molecule acetosyringone. We also present genetic data which support the hypothesis that VirA exists as a homodimer which is the functional state transducing the plant signal in an intersubunit mechanism. To our knowledge, this report provides the first evidence that a bacterial membrane-bound sensor kinase exists and functions as a homodimer in vivo.
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Affiliation(s)
- S Q Pan
- Department of Microbiology, University of Washington, Seattle 98195
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Wu ZL, Reichling M, Hu XQ, Balasubramanian K, Guenther KH. Absorption and thermal conductivity of oxide thin films measured by photothermal displacement and reflectance methods. Appl Opt 1993; 32:5660-5665. [PMID: 20856383 DOI: 10.1364/ao.32.005660] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Photothermal reflectance and photothermal displacement measurements of optical absorption and thermal conductivity are reported for electron-beam-(EB) deposited and ion-plated (IP) thin films of TiO(2), Ta(2)O(5), and ZrO(2). Of the particular set of samples investigated, the EB films have higher absorption than the IP films. The absorption of the EB samples decreases over a period of ~ 90 min on irradiations with an Ar-ion laser of 488-nm wavelength. By contrast, the absorption of the IP samples changes insignificantly or not at all. Photothermal displacement area scans of coating surfaces yield lower defect densities for the IP samples compared with the EB samples for all three oxide materials. The feasibility and limitations of photothermal measurements for thin-film optical and thermal characterizations are discussed.
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Gao XS, Chen FQ, Liu LX, Li JR, Li N, Wang XH, Niu HZ, Wu ZL, Zhu J. [18 incompatible medicaments that impair treatment]. Zhongguo Zhong Yao Za Zhi 1992; 17:754-6, 761. [PMID: 1304760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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