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To determine the effect of Ad-E1A gene therapy on in vivo radiosensitivity to nasopharyngeal carcinoma.CNE-2Z cells (2 x 10(5)) were subcutaneously injected into nude mice to develop tumor (1-3 mm) 6 days later. The tumor-bearing mice were then randomly divided into 6 groups (10 mice per group) for PBS treatment or treatment with radiotherapy, Ad-E1A, or Ad-beta-gal alone or radiotherapy in combination with Ad-E1A or Ad-beta-gal. The mice were treated with Ad-E1A or Ad-beta-gal (5 x 10(9) plaque forming units) by intratumoral injection twice weekly for 2 weeks at beginning of week 2. The mice treated with radiotherapy in combination with Ad-E1A or Ad-beta-gal received 2 Gy radiotherapy daily for 5 days following the first week of treatment with Ad-E1A or Ad-beta-gal. Control mice received PBS therapy or radiotherapy only after tumor cells were injected. When the size of tumor exceeded 2 cm, the mice were killed and the tumors underwent immunohistochemical analysis for VEGF and CD34 expression and TUNEL assay for apoptosis.The growth delay time was longest in the Ad-E1A plus radiotherapy group. Tumors treated with Ad-E1A plus radiotherapy were 4.7-fold smaller than those treated with radiotherapy alone and 5.3-fold smaller than those treated with Ad-E1A alone. The survival rate of tumor-bearing mice treated with Ad-E1A plus radiotherapy was significantly higher than that of other treatment groups. The vessel density and the VEGF expression were significantly lower in tumors treated with Ad-E1A plus radiotherapy than those treated with radiotherapy alone, Ad-E1A alone, Ad-beta-gal alone, or Ad-beta-gal plus radiotherapy (P0.01). TUNEL staining revealing apoptosis can be detected in the Ad-E1A group, radiotherapy group, Ad-E1A plus radiotherapy group, and more apoptosis can be detected in tumors treated with Ad-E1A plus radiotherapy than those of other treatment groups.E1A gene therapy can effectively enhance the nasopharyngeal carcinoma sensitivity to the radiotherapy by down-regulating VEGF expression and inducing apoptosis.

To explore the reversal effect and mechanism of lobeline on the multidrug-resistance (MDR) of human breast cancer cells MCF-7/ADM.In human breast cancer cell line MCF-7/ADM, MTT assay was used to determine the cell growth inhibiting ratio of MCF-7/ADM by ADM and Fu. Fluorospectorphotometer was employed to investigate the intracellular concentration of rhodamine123 to reflect the effect of lobeline on the activity of MDR-related protein P-glycoprotein (P-gp). Taking untreated MCF-7/ADM cells as controls, flow cytometry was applied to detect the intracellular concentration of rhodamine123 in MCF-7/ADM cell intervened with lobeline of 20 micromol/L.The sensitivity of MCF-7/ADM to ADM and Fu was significantly increased by lobeline in a dose-dependent manner. The inhibitive concentration 50 (IC(50)) of ADM declined from (44.81+/-0.43) mg/L to (16.72+/-0.75) mg/L with a reversion index of 2.68. The IC(50) of Fu declined from (53.12+/-1.60) mg/L to (38.90+/-1.43) mg/L with a reversion index of 1.37. The fluorescence intensity of lobeline-treated cells was significantly higher than that of the controls, when the concentration of lobeline was more than 10 micromol/L. With fewer side effects, the reversal efficacy of 20 micromol/L lobeline was 71.6% of the classical MDR reversal agent of verapamil at the same concentration.Lobeline can reverse the MDR of MCF-7/ADM cells by inhibiting the activity of P-glycoprotein.

To determine the effect of Ad-E1A gene therapy on the radiosensitivity of nasopharyngeal carcinoma cell by downregulating the expression of VEGF in vitro.The human nasopharyngeal carcinoma CNE-2Z cell lines were investigated. The recombinant adenovirus vector containing E1A gene was used for this study. After CNE-2Z cells was treated with PBS, Ad-beta-gal and Ad-E1A for 48 h, the three groups were irradiated in different doses at 0, 2.4, 6, 8 and 10 Gy, the cytotoxicity was determined by MTT assay and cell cycle was analysis by flow cytometry. The VEGF expression were evaluated by RT-PCR assay and immunocytochemical analysis.Significant cell deaths by IR were observed in a dose dependent manner in the three group CNE-2Z cells. After transduction of the E1A gene into CNE-2Z cells, the sensitivity of these cells to radiation was enhanced than the PBS treated group and Ad-beta-gal treated group. Cell growth inhibition in Ad-E1A group by IR was strongly enhanced than Ad-beta-gal treated group and PBS treated group. RT-PCR assay and immunocytochemical analysis showed VEGF expression was downregulated in Ad-E1A treated group.E1A gene therapy can effectively enhance the nasopharyngeal carcinoma cell sensitivity to the radiotherapy by down-regulating VEGF expression. These findings may pave the way for efficient radiation-gene therapy to NPC in future.

Stress corrosion cracking (SCC) of austenitic stainless steel serviced in aggressive environment often occurs in power, petrochemical industry, and leads to premature equipment failure and great economic loss. This paper focuses on the problem of the SCC on the nozzle of hydrogenation reactor which is caused due to alkali cleaning. Susceptibility for SCC was evaluated by Slow Strain Rate Test (SSRT) for as-rolled 304L and 316L stainless steel (SS) in low concentration sodium hydroxide solution with high temperature. The effects of different concentration of sodium hydroxide and different solution temperatures on SCC were investigated at the strain rate of 1 × 10−6s−1. After SSRT was performed, fractograph of the fractured specimens was analyzed by using scanning electron microscopy (SEM). On the basis of this, fracture characteristic and susceptibility of SCC of 304L and 316L stainless steel were compared in low concentration sodium hydroxide solution with high temperature.

Nasopharyngeal carcinoma (NPC) is one of the common malignant tumors in China. Radiotherapy and chemotherapy are the main therapy methods for NPC. To enhance the specific antitumor effect, a novel vector with radiosensitivity and tumor specificity was constructed in this study, which enables the reduction of dosage of radiation and chemotherapeutic drugs due to its double killing effect. Four DNA elements, Egr-1 promoter, Cytosine deaminase (CD) gene, hTERT promoter, Survivin antisense oligonucleotides were amplified and constructed in pcDNA3.1 vector. CD and Survivin gene expression in CNE-2 cells were detected by RT-PCR. High performance liquid chromatography (HPLC) was employed to determine the transformation from the prodrugs 5-FC to 5-FU. Hoechst33258 staining of the nuclei and methylthiazolyl tetrazolium(MTT) assay were applied to detect apoptosis and cell survivability, respectively. In addition, the anti-tumor effects were examined in vivo by injecting cells with different vectors into nude mice. Our results revealed a notable killing effect of combined treatment with 5-FC and radiation on CNE-2 cells transfected with vectors in vitro. This effect was especially notable on pEC-TS transferred cells, which showed 57% of cells were killed. In vivo, an obvious suppression of tumor was displayed in pEC-TS group, which was significantly different from other groups (p < 0.05). Consequently, this expression cassette may have a great therapeutic potential for the treatment of NPC.

For the past fifteen years, automotive safety engineers have mainly relied on the Control Volume (CV) approach to simulate airbag deployment. The CV approach assumes that the gas is uniformly distributed in an inflated bag and therefore the airbag fabric is subject to uniform pressure. This assumption is true only when the airbag is fully deployed, and therefore makes CV approach inappropriate for Out-of-Position (OOP) safety analysis in which an occupant is in close proximity to the air bag module when it deploys, and therefore airbag-occupant interaction occurs before the bag is fully inflated. This paper describes the theory and validation of a new airbag simulation tool, an ALE-based (Arbitrary-Lagrange-Eulerian) approach. This tool, developed by Livermore Software Technology Corporation (LSTC), is aimed at using ALE as a CFD (Computational Fluid Dynamics) tool to model the gas flow inside a deploying airbag and the interaction between the airbag and the inflator gas. The validation of this methodology is performed through comparing the simulation results with test results of various test setup and airbag design.Copyright © 2007 by ASME

The authors investigate two competing hypotheses about how chronic vividness of imagery interacts with the vividness and salience of information in decision making. Results from four studies, covering a variety of decision domains, indicate that chronic imagery vividness rarely amplifies the effects of vivid and salient information. Imagery vividness may, in fact, attenuate the effects of vivid and salient information. This is because, relative to nonvivid imagers, vivid imagers rely less on information that appears obvious and rely more on information that seems less obvious. This tendency is so robust that vividness of imagery may amplify the effects of vivid information only when this information is the only information available in the decision field. The findings seem to reflect vivid imagers' tendency to totally immerse themselves in a decision problem and scrutinize the available information creatively. Copyright 2000 Academic Press.

The evolution of the phase behaviour and lyotropic phase structures formed in the tetramethylammonium perfluorodecanoate (C10TMA)–water system upon the addition of a third component (tetramethylammonium chloride (TMACl) or 1H, 1H-perfluoro-1-decanol (C10ol)) have been studied using optical polarizing microscope, 2H NMR and small angle X-ray scattering (SAXS) in order to understand the correlated mesh phase with Rm space group. With increasing concentration of both additives, the Mh1(Rm) phase changes to a random mesh phase Mh1(0) via a two phase region. The structure of the Mh1(Rm) phase is essentially unaltered with addition of TMACl or C10ol until the phase change to Mh1(0). With higher additive concentration, the water fraction within a mesh layer of the Mh1(0) phase is decreased. It is proposed that the transition from the Mh1(0) to Mh1(Rm) phases is driven by a reduction in the electrostatic interlayer interaction enabling non-electrostatic repulsive interactions to dominate. This is because of the strong association of the TMA counter ion with the head group region, the increase of water within the mesh layers and the decrease in separation of the mesh layers in the Mh1(Rm) phase. It is also shown that the hydrophobic counter ion has to be small relative to the surfactant for both mesh and correlated mesh to occur.

The reactions of RhCl(PBz3)3 with H2 and pyridine or 4-methylpyridine yield RhCl(H)2(PBz3)2(py) and RhCl(H)2(PBz3)2(4-Me-py), respectively. These species undergo hydride site exchange via the loss of the pyridyl donor and formation of RhCl(H)2(PBz3)2 which contains equivalent hydride ligands; for the py system the activation free energy, deltaG++300, is 57.4 +/- 0.1 kJ mol(-1) while for 4-Me-py the value is 59.6 +/- 0.3 kJ mol(-1). These products only showed parahydrogen enhancement in the corresponding hydride resonances when a sacrificial substrate was added to promote hydrogen cycling. When RhCl(PPh3)3 was used as the precursor similar observations were made, while when RhCl(PCy3)2(C2H4) was examined, H2 addition led to the formation of the binuclear complex (H)2Rh(PCy3)2(micro-Cl)2Rh(H)2(PCy3)2 which was differentiated from RhCl(H)2(PCy3)2 on the basis of the similarity in diffusion coefficient (5.5 x 10(-9) m2 s(-1)) to that of (H)2Rh(PPh3)2(micro-Cl)2Rh(PPh3)2 (5.3 x 10(-9) m2 s(-1)). The detection of RhCl(H)2(PCy3)2(py) was facilitated when pyridine was added to a solution of RhCl(PCy3)2(C2H4) before the introduction of H2. During these reactions trace amounts of the double substitution products, RhCl(H)2(phosphine)(py)2, were also detected.

This paper presents an occupant-first approach, which allows for the simultaneous consideration of vehicle structure and the design of the occupant restraint system in the early stages. There are many difficulties in solving this problem, such as the large number of design variables, the large number of constraints and the highly non-linear nature of the occupant's responses. An efficient genetic algorithm (GA) is applied to deal with the challenges involved in the optimal design of the vehicle target pulse and the occupant restraint system. The methodology is demonstrated through a vehicle design problem. The results show that the occupant-first approach is effective and the GA is a valuable optimisation tool which can be used to achieve design targets.

In this research we examine the motivational influence of regulatory focus on revealed time preference. Drawing on regulatory focus research, we hypothesize an interaction effect between regulatory focus and valence such that, compared with prevention focus, promotion focus is associated with lower discount rate in the gain domain and a higher discount rate in the loss domain. This prediction was tested in three laboratory experiments where participants revealed their preference for intertemporal tradeoffs among hypothetical monetary rewards or payments. The data provide strong empirical support for the hypothesized interaction effect. These results highlight the importance of incorporating motivational influences in theoretical treatment of time discounting. The implications of the present research for the marketing of certain financial products that involve intertemporal tradeoffs (such as loans) are also discussed.