关键词：
Laser processing;Metals and alloys;Amorphous alloys;Femtosecond laser micromachining;Noncrystalline
摘要：
Femtosecond laser micromachining of a Zr-based amorphous alloy in air, including measuring the ablation threshold, micro-drilling and trenching, was investigated. The threshold of ablating this amorphous alloy was determined by experiment. Laser-induced ablation and associated damage were examined by means of optical microscope, scanning electron microscopy, transmission electron microscopy and electron diffraction diagram. The results show that conventional processing method induced defects in the vicinity of machined area, such as crystallization, molten trace and spatter, were absent in femtosecond laser ablation area with selected parameters. This indicates that femtosecond laser ablation is a promising method for micromachining amorphous alloys without crystallization.
摘要：
Boosting myocardial resistance to acute as well as chronic ischemic damage would ameliorate the detrimental effects of numerous cardiac pathologies and reduce the probability of transition to heart failure. Experimental cardiology has pointed to ischemic and pharmacological pre- as well as post-conditioning as potent acute cardioprotective manipulations. Additional exciting experimental strategies include the induction of true regenerative and/or angiogenic responses to the damaged heart, resulting in sustained structural and functional beneficial effects. Fibroblast growth factor-2 (FGF-2), an endogenous multifunctional protein with strong affinity for the extracellular matrix and basal lamina and well-documented paracrine, autocrine and intacellular modes of action, has been shown over the years to exert acute and direct pro-survival effects, irrespectively of whether it is administered before, during or after an ischemic insult to the heart. FGF-2 is also a potent angiogenic protein and a crucial agent for the proliferation, expansion, and survival of several cell types including those with stem cell properties. Human clinical trials have pointed to a good safety record for this protein. In this review, we will present a case for the low molecular weight isoform of fibroblast growth factor-2 (lo-FGF-2) as a very promising therapeutic agent to achieve powerful acute as well as sustained benefits for the heart, due to its cytoprotective and regenerative properties.
摘要：
The sensitivity of cancer cells as well as normal cells in response to ionizing radiation (IR) is believed to be associated with the early inducible expression of specific genes. Using cDNA microarray technology, here we explored and compared the global transcriptional changes in human lymphoblastoid AHH-1 cells irradiated with 0.05-, 0.2-, 0.5-, 2.0- and 10-Gy doses of gamma-rays 4 h after exposure. A dose as low as 0.05 Gy was efficient in inducing a transcriptional response including the up-regulation of 25 genes, some of which are involved in signal transduction pathways, e.g. BMPR2, GPR124, MAPK8IP2 and AGGF1, and the down-regulation of 18 genes. Expression of some genes was altered only at a specific dose. Most importantly, we discovered a number of radiation-response genes, e.g. DNA repair gene XPC, tumor protein p53 inducible protein 3 gene (TP53I3), immediate early response 5 gene, whose transcriptional levels were increased or depressed by IR in a dose-dependent trend within the dose range 0.05-10 Gy. The dose-dependent induced expression of TP53I3 and XPC was confirmed by Northern blot analyses. Using quantitative real-time PCR, we further confirmed that XPC gene induction was dose dependent as well as time dependent, reaching a peak 4 h post-2 Gy and 10 h post-0.05 Gy. The maximum induced expression level of the XPC gene was higher after 2 Gy (3.2-fold) than 0.05 Gy (1.93-fold). The identification of these radiation-inducible genes, especially those exhibiting a dose-dependent response, not only expands our knowledge of the mechanisms underlying the diverse biological effects induced by IR, but provides candidates for developing novel biomarkers of radiation injury.
作者：
Xie Dong*;Wang Han-qing;Deng Qi-hong;Xiong Jun
期刊：
中南大学学报(英文版),2007年14:66-70 ISSN：2095-2899
通讯作者：
Xie Dong
作者机构：
[Xie Dong; Deng Qi-hong] Cent S Univ, Sch Energy Sci & Engn, Changsha 410083, Peoples R China.;[Xie Dong; Xiong Jun] Univ S China, Sch Urban Construct, Hengyang 421001, Peoples R China.;[Wang Han-qing] Hunan Univ Technol, Dept Civil Engn, Zhuzhou 412008, Peoples R China.
通讯机构：
[Xie Dong] C;Cent S Univ, Sch Energy Sci & Engn, Changsha 410083, Peoples R China.
关键词：
indoor air environment;ventilation patterns;numerical simulation;human comfort
摘要：
The different ventilation patterns inside a room containing one person and office furniture arranged by different inlet/outlet configurations was investigated. The numerical simulation was first adopted to predict air flow pattern and ventilation performance. Then, a laboratory experimental measurement at room air distribution in a fall-scale test chamber was conducted using the hot wire velocimetry to validate the simulation results. In addition, questionnaire surveys were conducted from the different gender groups in order to assess indoor air quality and human comfort in workplace micro-environments. The distribution of supply/exhaust air in the study was investigated in isothermal conditions using different supply air velocities. The results indicate that the ventilation efficiency and human comfort might be dominantly influenced by location of diffuser rather than air change rate.,
关键词：
chemical behavior of topology;valence electron;QSPR;lanthanide;actinide
摘要：
We introduce the chemical behavior of topology for the first time which consists of the topological growing power and the topological blocking power. On the basis of the principle, the OET (orbital-energy topological index) was proposed by revising the valence electron distance matrix with the orbital energy. The results demonstrate that OET has good application to the physicochemical properties of lanthanide and actinide, especially to the spectral properties which have not been reported by means of QSPR (quantitative structure-property relationships). The results of LOO CV (leave-one-out cross-validation) verify the good stability and predictive ability of the models using the cross-validation parameters: PRESS/SSY, SEPCV, R CV, SPRESS and PSE with the PRESS/SSY ratio ranging between 0.000 6 and 0.114 8. Compared with the other methods, this work provides an easier way yielding results close to or better than the others. It is on the basis of the chemical behavior of topology that leads to the good and wide application of this method.
期刊：
Indian Journal of Pure and Applied Mathematics,2007年38(6):579-587 ISSN：0019-5588
通讯作者：
Li, Xianyi
作者机构：
[Li, Xianyi; Li, XY] Nanhua Univ, Sch Math & Phys, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Li, Xianyi] N;Nanhua Univ, Sch Math & Phys, Hengyang 421001, Hunan, Peoples R China.
关键词：
Global asymptotic stability;Length of semicycle;Periodicity;Perturbation;Rational difference equation;Semicycle;Trajectory structure rule
摘要：
In this paper the following fourth-order rational difference equation Xn+1 = Xnxn-2b + x n-3b + a / xn-2b + x nxn-3b + a, n = 0, 1, 2, . . ., where a, b ε [0, ∞) and the initial values x-3, x-2, x-1, x0 ε (0, ∞), is considered. It is found that the perturbation of the initial values may lead to the variation of the trajectory structure rule for the solutions of the above equation. That is, with the change of the initial values, the successive lengths of positive and negative semicycles for nontrivial solutions of this equation is found to periodically occur with prime period 15, i.e., . . . 4+, 1 -, 1+, 1-, 2+, 2-, 1 +, 3-, 4+, 1-, l+, 1 -, 2+, 2-, 1+, 3-, 4 +, 1-, l+, 1-, 2+, 2 -, 1+, 3-, . . . . By the use of the rule, the positive equilibrium point of the equation is verified to be globally asymptotically stable.
期刊：
International Journal of Cardiology,2007年120(3):331-337 ISSN：0167-5273
通讯作者：
Fu, Mingde
作者机构：
[Fu, Mingde] Sichuan Univ, W China Hosp, Lab Endocrinol & Metab, Chengdu 610041, Peoples R China.;Nanhua Univ, Dept Biochem & Mol Biol, Hengyang, Hunan, Peoples R China.;Hoist Grp Postdoctoral Work Stn, Chengdu, Sichuan, Peoples R China.
通讯机构：
[Fu, Mingde] S;Sichuan Univ, W China Hosp, Lab Endocrinol & Metab, Chengdu 610041, Peoples R China.
关键词：
2-Dimensional gel electrophoresis-immunodetection;Combined hyperlipidemia;HDL subclasses;Hypercholesterolemia
摘要：
Background: Alterations in plasma lipid levels can influence the composition, content, and distribution of plasma lipoprotein subclasses that effect atherosclerosis risk. Hypercholesterolemia and combined hyperlipidemia are common forms of atherogenic dyslipoproteinemia. This study evaluates the alterations of high-density lipoprotein (HDL) subclasses in hypercholesterolemic and combined hyperlipidemic subjects. Methods: Apolipoprotein A-I contents of plasma HDL subclasses were quantitated by 2-dimensional gel electrophoresis in 242 normolipidemic subjects, 66 hypercholesterolemic subjects and 59 combined hyperlipidemic subjects. Results: Compared with the normolipidemic subjects, apolipoprotein A-I contents of small-sized pre-beta(1)-HDL, HDL3c, HDL(3b)and HDL(3a)were significantly higher in both hypercholesterolemic subjects (p <.01, p <.05, p <.01 and p <.05, respectively) and combined hyperlipidemic subjects (p <.0l,p <.05,p <.01 and p <.01, respectively). In contrast, apolipoprotein A-I contents of large-sized HDL2a and HDL2b were significantly lower in hypercholesterolemic subjects (p <.05 and p <.01, respectively) as well as combined hyperlipidemic subjects (p <.01 and p <.01, respectively). In addition, pre-beta(1)-HDL increased significantly (p <.05) while HDL2a and HDL2b decreased significantly (p <.05 and p <.0 1, respectively) in combined hyperlipidemic group versus hypercholesterolemic subjects. With the elevation of triglyceride levels, pre-beta(1)-HDL, and HDL3a. increased successively, however, HDL2a and HDL2b decreased successively in subjects with total cholesterol levels greater than 240 mg/dl. Conclusions: The particle size of HDL shifted towards smaller size in hypercholesterolemic subjects, and that the shift was more prominent in combined hyperlipidemic subjects. The alternations mentioned above indicate that HDL maturation might be abnormal, and reverse cholesterol transport (RCT) might be weakened. (c) 2006 Elsevier Ireland Ltd. All rights reserved.
摘要：
Bcl-XL is overexpressed in a variety of human tumors and is involved in tumorigenesis and chemoresistance. This study investigated the inhibitory effect of the hairpin Bcl-XL small interfering RNA (siRNA) on the expression of the Bcl-XL gene in the cisplatin (DDP)-resistant human lung adenocarcinoma cell line A549/DDP, and the effect of Bcl-XL siRNA on drug sensitization in A549/DDP cells. Bcl-XL siRNA and negative siRNA plasmids were constructed and stably transfected into A549/DDP cells. Reverse transcription-polymerase chain reaction and Western blot analysis were used to detect the target gene expression. Spontaneous apoptosis of cells was detected by acridine orange and ethidium bromide staining. Drug sensitivity of the cells to DDP was analyzed with dimethylthiazol-diphenyltetrazolium bromide (MTT) and flow cytometry. Expression levels of Bcl-XL mRNA and protein in siRNA stable transfectants were clearly reduced as compared with negative siRNA transfectants and untreated cells. MTT results indicated that Bcl-XL transfectants had a higher cell inhibition rate than the negative vector or untreated cells after treatment with 0.2–200 μg/ml DDP. Flow cytometry revealed increased apoptosis in Bcl-XL siRNA cells. After the addition of 20 μg/ml DDP, siRNA targeting of the Bcl-XL gene specifically down-regulated gene expression in A549/DDP cells, increased spontaneous apoptosis, and sensitized cells to DDP. The results showed that Bcl-XL siRNA contributed to an increase of DDP-induced cell death in non-small-cell lung cancer and sensitized cells to DDP, leading to increased the effectiveness of the drug in treating non-small-cell lung cancer.
期刊：
International Journal of Cancer,2007年121(10):2301-2306 ISSN：0020-7136
通讯作者：
Cao, Deliang
作者机构：
So Illinois Univ, Sch Med, SimmonsCooper Canc Inst, Dept Med Microbiol & Cell Biol, Springfield, IL 62794 USA.;Nanhua Univ, Sch Life Sci & Technol, Inst Pharm & Pharmacol, Div Pharmacoproteom, Hengyang, Hunan, Peoples R China.;Mem Hosp Carbondale, Dept Pathol, Carbondale, IL USA.;[Cao, Deliang] So Illinois Univ, Sch Med, SimmonsCooper Canc Inst, Dept Med Microbiol & Cell Biol, 913 N Rutledge St, Springfield, IL 62794 USA.
通讯机构：
[Cao, Deliang] S;So Illinois Univ, Sch Med, SimmonsCooper Canc Inst, Dept Med Microbiol & Cell Biol, 913 N Rutledge St, Springfield, IL 62794 USA.
关键词：
aldose reductase-like-1;aldo-keto reductase family 1 B 10;reactive carbonyls;gene silencing;clonogenic growth
摘要：
Aldo-keto reductase family 1 B10 (AKR1B10), a member of aldo-keto reductase superfamily, is overexpressed in human hepatocellular carcinoma, lung squamous cell carcinoma and lung adenocarcinoma. Our previous study had demonstrated that the ectopic expression of AKR1B10 in 293T cells promotes cell proliferation. To evaluate its potential as a target for cancer intervention, in the current study we knocked down AKR1B10 expression in HCT-8 cells derived from a colorectal carcinoma, using chemically synthesized small interfering RNA (siRNA). The siRNA 1, targeted to encoding region, downregulated AKR1B10 expression by more than 60%, and siRNA 2, targeted to 3' untranslational region, reduced AKR1B10 expression by more than 95%. AKR1B10 silencing resulted in approximately a 50% decrease in cell growth rate and nearly 40% suppression of DNA synthesis. More importantly, AKR1B10 downregulation significantly reduced focus formation rate and colony size in semisolid culture, indicating the critical role of AKR1B10 in HCT-8 cell proliferation. Recombinant AKR1B10 protein showed strong enzymatic activity to acrolein and crotonaldehyde, with K(m) = 110.1 +/- 12.2 microM and V(max) = 3,122.0 +/- 64.7 nmol/mg protein/min for acrolein and K(m) = 86.7 +/- 14.3 microM and V(max) = 2,647.5 +/- 132.2 nmol/mg protein/min for crotonaldehyde. AKR1B10 downregulation enhanced the susceptibility of HCT-8 cells to acrolein (25 microM) and crotonaldehyde (50 microM), resulting in rapid oncotic cell death characterized with lactate dehydrogenase efflux and annexin-V staining. These results suggest that AKR1B10 may regulate cell proliferation and cellular response to additional carbonyl stress, thus being a potential target for cancer intervention.
作者机构：
[Liao, Xinyuan] Nanhua Univ, Sch Math & Phys, Hengyang 421001, Hunan, Peoples R China.;Shanghai Univ, Dept Mat Sci, Shanghai 200444, Peoples R China.;Shanghai Normal Univ, Math & Sci Coll, Shanghai 200234, Peoples R China.
通讯机构：
[Liao, Xinyuan] N;Nanhua Univ, Sch Math & Phys, Hengyang 421001, Hunan, Peoples R China.
期刊：
Journal of Diabetes Research,2007年2007:67435 ISSN：2314-6745
通讯作者：
Lin, GP
作者机构：
[Lin, Guo-Ping; Jiang, Tao; Hu, Xiao-Bo; Qiao, Xin-Hui; Tuo, Qin-Hui] Univ S China, Sch Life Sci & Technol, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Lin, GP ] ;Univ S China, Sch Life Sci & Technol, Hengyang 421001, Hunan, Peoples R China.
摘要：
The Siraitia grosvenorii polysaccharide (SGP) from the Siraitia grosvenorii (Swingle) was isolated and purified. The therapeutic effects of SGP on diabetic rabbits induced by feeding high fat/high sucrose chow were studied. After administration of SGP for 4 weeks, the fasting blood glucose (FBG), plasma insulin levels (INS), plasma total cholesterol (TC), triglyceride (TG), and HDL-C were assayed. The results showed that administration of SGP can significantly decrease plasma total cholesterol, triglyceride, and glucose levels; and increase HDL-C levels after 4 weeks of treatment. The antihyperglycaemic effect of SGP at dose of 100 mg.kg(-1) bw was the most significant in three dosage groups. Furthermore, SGP could restore the blood lipid levels of diabetic rabbits (P<.05). These data indicate that SGP not only ameliorates the lipid disorder, but also lowers plasma glucose levels. So SGP have obvious glucose-lowering effect on hyperglycaemic rabbits induced by feeding high fat/high sucrose chow, its mechanism may be related to amelioration of lipid metabolism and restoring the blood lipid levels of hyperglycaemic rabbits.
