bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical simulation of natural and mixed convection flows by Galerkin‐characteristic method
Authors: El‐Amrani Mofdi , Seaïd Mohammed 
Published: October 2006

AbstractA numerical investigation is performed to study the solution of natural and mixed convection flows by Galerkin‐characteristic method. The method is based on combining the modified method of characteristics with a Galerkin finite element discretization in primitive variables. It can be interpreted as a fractional step technique where convective part and Stokes/Boussinesq part are treated separately. The main feature of the proposed method is that, due to the Lagrangian treatment of convection, the Courant–Friedrichs–Lewy (CFL) restriction is relaxed and the time truncation errors are reduced in the Stokes/Boussinesq part. Numerical simulations are carried out for a natural convection in squared cavity and for a mixed convection flow past a circular cylinder. The computed results are compared with those obtained using other Eulerian‐based Galerkin finite element solvers, which are used for solving many convective flow models. The Galerkin‐characteristic method has been found to be feasible and satisfactory. Copyright © 2006 John Wiley & Sons, Ltd.
Direct sensitivity analysis for smooth unsteady compressible flows using complex differentiation
Authors: Lu Shang‐Yi , Sagaut Pierre 
Published: October 2006

AbstractA method for the direct computation of the instantaneous sensitivities of unsteady compressible flows is proposed. It is based on the complex differentiation of the full compressible Navier–Stokes equations and does not require the storage of the unsteady flow solution to be differentiated. The method does not rely on any assumption on the basic Navier–Stokes solver, and can therefore be implemented in a straightforward way. The method is assessed on several cases, including a two‐dimensional subsonic mixing layer. It is observed that the sensitivity patterns can be interpreted thanks to Kovasznay's decomposition for perturbations in a compressible flow. Copyright © 2006 John Wiley & Sons, Ltd.
Photophysical Investigations on Photoinitiators with Covalently Linked Thioxanthone Sensitizer Moieties
Authors: Dietliker Kurt , Broillet Stephanie , Hellrung Bruno , Rzadek Piotr , Rist Guenther , Wirz Jakob , Neshchadin Dmytro , Gescheidt Georg 
Published: October 2006

AbstractThe photophysical properties of three photoinitiators with a covalently linked thioxanthone sensitizer unit absorbing up to 410 nm were investigated by laser‐flash photolysis and CIDNP spectroscopy. These complementary techniques revealed two competing reaction pathways of the molecular dyads 1–3: i) triplet‐energy transfer from the sensitizer to the morpholine moiety followed by α‐cleavage to yield a radical pair, which initiates radical polymerization, and ii) bimolecular electron transfer from the morpholine to the thioxanthone subunit followed by proton transfer. The relative efficiency of these routes is determined by the triplet energy of the photoinitiator moiety relative to that of the sensitizer.
Rearrangements in Model Peptide‐Type Radicals via Intramolecular Hydrogen‐Atom Transfer
Authors: Moran Damian , Jacob Rebecca , Wood Geoffrey P. F. , Coote Michelle L. , Davies Michael J. , O'Hair Richard A. J. , Easton Christopher J. , Radom Leo 
Published: October 2006

AbstractIntramolecular H‐atom transfer in model peptide‐type radicals was investigated with high‐level quantum‐chemistry calculations. Examination of 1,2‐, 1,3‐, 1,5‐, and 1,6[C ↔ N]‐H shifts, 1,4‐ and 1,7[C ↔ C]‐H shifts, and 1,4[N ↔ N]‐H shifts (Scheme 1), was carried out with a number of theoretical methods. In the first place, the performance of UB3‐LYP (with the 6‐31G(d), 6‐31G(2df,p), and 6‐311+G(d,p) basis sets) and UMP2 (with the 6‐31G(d) basis set) was assessed for the determination of radical geometries. We found that there is only a small basis‐set dependence for the UB3‐LYP structures, and geometries optimized with UB3‐LYP/6‐31G(d) are generally sufficient for use in conjunction with high‐level composite methods in the determination of improved H‐transfer thermochemistry. Methods assessed in this regard include the high‐level composite methods, G3(MP2)‐RAD, CBS‐QB3, and G3//B3‐LYP, as well as the density‐functional methods B3‐LYP, MPWB1K, and BMK in association with the 6‐31+G(d,p) and 6‐311++G(3df,3pd) basis sets. The high‐level methods give results that are close to one another, while the recently developed functionals MPWB1K and BMK provide cost‐effective alternatives. For the systems considered, the transformation of an N‐centered radical to a C‐centered radical is always exothermic (by 25 kJ ⋅ mol−1 or more), and this can lead to quite modest barrier heights of less than 60 kJ ⋅ mol−1 (specifically for 1,5[C ↔ N]‐H and 1,6[C ↔ N]‐H shifts). H‐Migration barriers appear to decrease as the ring size in the transition structure (TS) increases, with a lowering of the barrier being found, for example when moving from a rearrangement proceeding via a four‐membered‐ring TS (e.g., the 1,3[C ↔ N]‐H shift, CH3C(O)NH. → .CH2C(O)NH2) to a rearrangement proceeding via a six‐membered‐ring TS (e.g., the 1,5[C ↔ N]‐H shift, .NHCH2C(O)NHCH3 → NH2CH2C(O)NHCH2.).
Titanocene‐Mediated Homolytic Opening of Epoxysilanes
Authors: Puljic Nicolas , Albert Matthias , Dhimane Anne‐Lise , Fensterbank Louis , Lacôte Emmanuel , Malacria Max 
Published: October 2006

AbstractThe titanocene(III) chloride mediated opening of silyloxiranes has been examined. Electron transfer from the metal leads to α‐silyl radicals with total regiocontrol. The radicals could be trapped by various olefins, and the corresponding adducts were obtained in good yields (Table). Further substitution of the oxirane by alkyl groups proved detrimental to the reactions, but ring opening remained essentially regioselective.
The Tris(trimethylsilyl)silane/Thiol Reducing System: A Tool for Measuring Rate Constants for Reactions of Carbon‐Centered Radicals with Thiols
Authors: Chatgilialoglu Chryssostomos 
Published: October 2006

AbstractAn extension of the well‐known ‘free‐radical‐clock’ methodology is described that allows one to determine the rate constants of carbon‐centered radicals with a variety of thiols by using the tris(trimethylsilyl)silane/thiol couple as a reducing system. A total of 20 rate constants for the hydrogen abstraction from a variety of alkyl‐, silyl‐, and aryl‐substituted thiols by the primary‐alkyl radical 2 in toluene at 80° were determined with the aid of the 5‐exo‐trig cyclization as a timing device. Further, seven rate constants for the hydrogen abstraction from a variety of alkyl‐ and silyl‐substituted thiols by the acyl radical 9 in benzene at 80° were measured using the decarbonylation process as a timing device. The rate constants varied over two orders of magnitude from 106 to 108 M−1 s−1. Substituent effects were rationalized. The radical‐trapping abilities of these reducing systems and those of other common hydrogen donors were compared.
Trifluoromethyl‐Radical‐Mediated Carbonylation of Alkanes Leading to Ethynyl Ketones
Authors: Uenoyama Yoshitaka , Fukuyama Takahide , Morimoto Keisuke , Nobuta Osamu , Nagai Hidefumi , Ryu Ilhyong 
Published: October 2006

AbstractThe carbonylation of alkanes 1 under radical‐reaction conditions was examined by using ethynyl triflone A as the unimolecular chain‐transfer (UMCT) reagent. Good to moderate yields of ethynyl ketones 2 were prepared by means of this three‐component coupling reaction. Higher CO pressures as well as lower concentrations of triflone A improved the efficiency of the reaction over the direct addition, the latter leading to alkylated ethynes 3. In contrast to the reaction with A, the reaction of cyclohexane (1a) with allyl triflone B (= ethyl 2‐methylene‐3‐[(trifluoromethyl)sulfonyl]propanoate) in the presence of CO gave a mixture of carbonylation products, including 8a formed from two molecules each of cyclohexane, CO, and allyl triflone B.
Suppression of ovarian cancer by muscle‐mediated expression of soluble VEGFR‐1/Flt‐1 using adeno‐associated virus serotype 1‐derived vector
Authors: Takei Yuji , Mizukami Hiroaki , Saga Yasushi , Yoshimura Ichiro , Hasumi Yoko , Takayama Takeshi , Kohno Takahiro , Matsushita Takashi , Okada Takashi , Kume Akihiro , Suzuki Mitsuaki , Ozawa Keiya 
Published: October 2006

AbstractVascular endothelial growth factor (VEGF) is known to play a major role in angiogenesis in a variety of tumors. A soluble form of Flt‐1 (sFlt‐1), a VEGF receptor, is potentially useful as an antagonist of VEGF, and accumulating evidences suggest the applicability of sFlt‐1 in tumor suppression by means of anti‐angiogenesis. We previously demonstrated the efficacy of sflt‐1 gene expression in situ to suppress tumor growth and ascites in ovarian cancer. Here, we demonstrate the therapeutic applicability of muscle‐mediated expression of sFlt‐1 in tumor‐bearing mice. Initially, tumor suppressive action was confirmed by inoculating sFlt‐1‐expressing ovarian cancer (SHIN‐3) cells into mice, both subcutaneously and intraperitoneally. To validate the therapeutic efficacy in a more clinically relevant model, adeno‐associated virus vectors encoding sflt‐1 were introduced into mouse skeletal muscles and were subsequently inoculated with tumor cells. As a result, high serum sFlt‐1 levels were constantly observed, and the growth of both subcutaneously‐ and intraperitoneally‐inoculated tumors was significantly suppressed. No delay in wound healing or adverse events of neuromuscular damage were noted, body weight did not change, and laboratory data, such as those representing liver and renal functions, were not affected. These results indicate that sFlt‐1 suppresses growth and peritoneal dissemination of ovarian cancer by the inhibition of angiogenesis, and thus suggest the usefulness of gene therapy for ovarian cancer. © 2006 Wiley‐Liss, Inc.
Life‐style and environmental factors in the development of nasal NK/T‐cell lymphoma: A case–control study in East Asia
Authors: Xu Jing‐Xian , Hoshida Yoshihiko , Yang Woo‐Ick , Inohara Hidenori , Kubo Takeshi , Kim Gwi‐Eon , Yoon Joo‐Heon , Kojya Shizuo , Bandoh Nobuyuki , Harabuchi Yasuaki , Tsutsumi Kouichiro , Koizuka Izumi , Jia Xin‐Shan , Kirihata Mitsunori , Tsukuma Hideaki , Aozasa Katsuyuki 
Published: October 2006

AbstractCases of nasal NK/T‐cell lymphoma (NKTCL) occur occasionally in Asian and Latin American countries but rarely in Western countries. The etiological role of life‐style and environmental factors in nasal NKTCL was investigated. Five university hospitals in Japan and one each in Korea and China participated in this study; a total of 88 cases and 305 hospital controls were accrued during 2000–2005. The odds ratio (OR) of NKTCL obtained after adjustments of age, sex and country was 4.15 (95% confidence interval (CI), 1.74–9.87) for farmers, 2.81 (CI, 1.49–5.29) for producers of crops, 4.01 (CI, 1.99–8.09) for pesticide users, 11.65 (CI, 1.17–115.82) for residents near garbage burning plants, 2.95 (CI, 1.25–6.95) for former drinkers, and 0.49 (CI, 0.23–1.04) for current smokers. The ORs for crop producers, who minimized their exposure to pesticides by using gloves and glasses, and sprinkling downwind at the time of pesticide use, were 3.30 (95% CI, 1.28–8.54), 1.18 (95% CI, 0.11–12.13) and 2.20 (95% CI, 0.88–5.53), respectively, which were lower than those for producers who did not take these precautions. Exposure to pesticides and chemical solvents could be causative of NKTCL. Taken together, life‐style and environmental factors might be risk factors for NKTCL. © 2006 Wiley‐Liss, Inc.
Overexpression of regucalcin suppresses cell response for tumor necrosis factor‐α or transforming growth factor‐β1 in cloned normal rat kidney proximal tubular epithelial NRK52E cells
Authors: Nakagawa Taeko , Yamaguchi Masayoshi 
Published: October 2006

AbstractThe regulatory role of regucalcin on cell responses for tumor necrosis factor‐α (TNF‐α) or transforming growth factor‐β1 (TGF‐β1) was investigated using the cloned normal rat kidney proximal tubular epithelial NRK52E cells overexpressing regucalcin. NRK52E cells (wild type) and stable regucalcin (RC)/pCXN2‐transfected cells (transfectant) were cultured for 72 h in a medium containing 5% bovine serum (BS) to obtain subconfluent monolayers. After culture, cells were further cultured for 24–72 h in medium without BS containing either vehicle, TNF‐α (0.1 or 1.0 ng/ml of medium), or TGF‐β1 (1.0 or 5.0 ng/ml). Culture with TNF‐α or TGF‐β1 caused a significant decrease in the number of wild‐type cells. This decrease was significantly prevented in transfectants overexpressing regucalcin. Agarose gel electrophoresis showed the presence of low‐molecular‐weight deoxyribonucleic acid (DNA) fragments of adherent wild‐type cells cultured with TNF‐α (1.0 ng/ml) or TGF‐β1 (5.0 ng/ml). This DNA fragmentation was significantly suppressed in transfectants. TNF‐α‐ or TGF‐β1‐induced cell death was significantly prevented in culture with caspase‐3 inhibitor (10−8 M). Nitric oxide (NO) synthase activity in wild‐type cells was significantly increased by addition of calcium chloride (10 µM) and calmodulin (5 µg/ml) into the enzyme reaction mixture. This increase was significantly suppressed in transfectants. Culture with TNF‐α caused a significant increase in NO synthase activity in wild‐type cells. The effect of TNF‐α was not seen in transfectants. Culture with TGF‐β1 did not cause a significant increase in NO synthase activity in wild‐type cells and transfectants. Culture with TNF‐α or TGF‐β1 caused a remarkable increase in α‐smooth muscle actin in wild‐type cells. This increase was significantly prevented in transfectants. The expression of Smad 2 or NF‐κB mRNAs was significantly increased in transfectants as compared with that of wild‐type cells. Smad 3 or glyceroaldehyde‐3‐phosphate dehydrogenase (G3PDH) mRNA expression was not significantly changed in transfectants. NF‐κB mRNA expression in wild‐type cells was significantly increased with culture of TNF‐α. Smad 2 mRNA expression was significantly enhanced in wild‐type cells cultured with TGF‐β1. These effects of TNF‐α or TGF‐β1 were not significantly enhanced in transfectants. This study demonstrates that overexpression of regucalcin has suppressive effects on cell responses which are mediated through intracellular signaling pathways of TNF‐α or TGF‐β1 in kidney NRK52E cells. J. Cell. Biochem. 100: 1178–1190, 2007. © 2006 Wiley‐Liss, Inc.
A role for PLCγ2 in platelet activation by homocysteine
Authors: Leoncini Giuliana , Bruzzese Debora , Signorello Maria Grazia 
Published: October 2006

AbstractThe aim of this study was to examine the homocysteine effect on phospholipase Cγ2 (PLCγ2) activation and to investigate the signaling pathway involved. We found that homocysteine stimulated the tyrosine phosphorylation and activation of platelet PLCγ2. The tyrosine kinases p60src and p72syk appeared to be involved upstream. Reactive oxygen species were increased in homocysteine treated platelets. Likely oxidative stress could prime the non receptor‐mediated tyrosine kinase p60src, inducing phosphorylation and activation of p72syk. The antioxidant N‐acetyl‐L‐cysteine prevented the activation of these kinases. The phosphorylation and activation of PLCγ2 were greatly reduced by the inhibition of p72syk through piceatannol. Moreover indomethacin diminished the homocysteine effect on p60src, p72syk and PLCγ2, suggesting that thromboxane A2 could be involved. In addition the treatment of platelets with homocysteine caused intracellular calcium rise and protein kinase C activation. Finally homocysteine induced platelet aggregation, that was partially reduced by indomethacin and by N‐acetyl‐L‐cysteine of 35% or 50% respectively, while the PLCγ2 specific inhibitor U73122 diminished platelet response to homocysteine of 70%. Altogether the data indicate that PLCγ2 plays an important role in platelet activation by homocysteine and that the stimulation of this pathway requires signals through oxygen free radicals and thromboxane A2. J. Cell. Biochem. 100: 1255–1265, 2007. © 2006 Wiley‐Liss, Inc.
Gastric neuroendocrine carcinoma: Clinicopathologic review and immunohistochemical study of E‐cadherin and Ki‐67 as prognostic markers
Authors: Boo Yoon‐Jung , Park Sung‐Soo , Kim Jong‐Han , Mok Young‐Jae , Kim Seong‐Joo , Kim Chong‐Suk 
Published: October 2006

AbstractBackground and ObjectivesGastric neuroendocrine carcinoma (NEC) is an uncommon cancer of the stomach. The classification of NEC and its clinical behavior remains controversial, and prognostic markers and their therapeutic guidelines have not been clearly defined. The aim of this study was to evaluate the clinicopathologic characteristics of these tumors and analyze the expression of E‐cadherin and Ki‐67 as prognostic markers in gastric NECs.MethodsWe retrospectively reviewed 17 cases of gastric NECs. Tumor pathology was reviewed and the tumors were categorized as well‐differentiated NEC (n = 5) and poorly differentiated NEC (n = 12) according to the WHO classification. With the aim of evaluating the expression of E‐cadherin and Ki‐67 and their prognostic role in gastric NEC, immunohistochemical analysis of the tumors was performed.ResultsThe median survival of patients was 20.0 months (95% confidence interval (CI), 13.2–28.8). There was a statistically significant difference in overall survival between well and poorly differentiated NECs (P = 0.021). However, there was no significant difference in overall survival between patients with poorly differentiated small cell and large cell NEC (P = 0.796). Loss of E‐cadherin was correlated with lymph node metastasis (P= 0.044). A high Ki‐67 proliferation index (PI) (>60%) was correlated with tumor recurrence (P = 0.013) and histologic differentiation (P= 0.028).ConclusionsLoss of E‐cadherin may predict lymph node metastasis in gastric NECs. A high Ki‐67 PI (>60%) could be used as a prognostic marker to predict aggressive gastric NECs in addition to standard pathologic classification. J. Surg. Oncol. 2007;95:110–117. © 2007 Wiley‐Liss, Inc.
Speciation of arsenic by ion chromatography inductively coupled plasma mass spectrometry using ammonium eluents
Authors: Chen ZuLiang , Akter Kazi Farzana , Rahman Mohammad Mahmudur , Naidu Ravendra 
Published: October 2006

AbstractA method based on ion chromatography (IC) and inductively coupled plasma MS (ICP‐MS) was developed for the speciation of arsenic in water and soil extracts. An anion‐exchange column (G3154A/101) was used to separate As(III), As(V), dimethylarsinic acid (DMA), and monomethylarsonic acid (MMA) with excellent resolution. Various ammonium salts, including NH4H2PO4, (NH4)2HPO4, (NH4)2CO3, and NH4HCO3, were examined as eluents to reduce matrix interference from chloride and to solve clogging problems. The best arsenic speciation was obtained within 9 min with excellent resolution and without interference from high chloride concentrations using an eluent containing 7.5 mM (NH4)2HPO4 at pH 7.9. The detection limits for the target arsenic species ranged from 0.1 to 0.4 μg/L with direct injection of sample without matrix elimination. The proposed method was effectively demonstrated by determining arsenic species in contaminated waters and soils of Bangladesh.
The pediatric preclinical testing program: Description of models and early testing results
Authors: Houghton Peter J. , Morton Christopher L. , Tucker Chandra , Payne Debbie , Favours Edward , Cole Claire , Gorlick Richard , Kolb E. Anders , Zhang Wendong , Lock Richard , Carol Hernan , Tajbakhsh Mimi , Reynolds C. Patrick , Maris John M. , Courtright Joshua , Keir Stephen T. , Friedman Henry S. , Stopford Charles , Zeidner Joseph , Wu Jianrong , Liu Tiebin , Billups Catherine A. , Khan Javed , Ansher Sherry , Zhang Jian , Smith Malcolm A. 
Published: October 2006

AbstractBackgroundThe Pediatric Preclinical Testing Program (PPTP) is an initiative supported by the National Cancer Institute (NCI) to identify novel therapeutic agents that may have significant activity against childhood cancers. The PPTP has established panels of childhood cancer xenografts and cell lines to be used for in vivo and in vitro testing. These include panels for Wilms tumor, sarcomas (rhabdomyosarcoma, Ewing sarcoma, and osteosarcoma), neuroblastoma, brain tumors (glioblastoma, ependymoma, and medulloblastoma), rhabdoid tumors (CNS and renal), and acute lymphoblastic leukemia (ALL). Here, we describe the characteristics of the in vivo tumor panels and report results for the in vivo evaluation of two standard agents, vincristine and cyclophosphamide.ProceduresSolid tumors were grown subcutaneously in immune‐deficient mice and tumor dimensions were measured weekly. ALL xenografts were inoculated intravenously and human CD45‐positive cells were enumerated weekly.ResultsVincristine‐induced objective responses in 6 of 24 (25%) and cyclophosphamide‐induced objective responses in 18 of 28 (64%) solid tumor models. Comparable assessments of high levels of activity for these two agents were obtained using a tumor growth delay (TGD) measure. Both agents induced regressions in each of the ALL models evaluated.ConclusionsWe have established 51 solid tumor and 10 ALL in vivo models. The models identify vincristine and cyclophosphamide as having broad‐spectrum activity. The PPTP tumor panels appear to generally recapitulate the activity of these agents against specific childhood cancers and to have the potential for identifying novel agents having significant clinical activity. Pediatr Blood Cancer 2007;49:928–940. Published 2006 Wiley‐Liss, Inc.
Chinese herbal medicines used in pregnancy: a population‐based survey in Taiwan
Authors: Chuang Chao‐Hua , Hsieh Wu‐Shiun , Guo Yueliang Leon , Tsai Yih‐Jian , Chang Pei‐Jen , Lin Shio‐Jean , Chen Pau‐Chung 
Published: October 2006

AbstractPurposeTo explore the use (prevalence and related factors) of Chinese herbal medicines used by pregnant women.MethodsWe used multistage stratified systematic sampling to recruit 2048 postpartum women from the Taiwan national birth register between November and December 2003. Subjects underwent a home interview 6 months after their deliveries. A structured questionnaire was successfully applied to 87% of the sampled population.ResultsAt least one Chinese herbal medicine was used during pregnancy by 24.1% of the interviewed subjects. Pregnant women with threatened abortion appeared to use more Chinese herbal medicines than other pregnant women.ConclusionChinese herbal medicines are frequently used by pregnant women in Taiwan and are very frequently used by those with a threatened abortion. Copyright © 2006 John Wiley & Sons, Ltd.