bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of 4H‐tetrazolo[1,5‐a][1]benzazepines from the baylis‐hillman adducts of 2‐azidobenzaldehyde
Authors: Lee Chang Hoon , Song Young Seok , Cho Hyun In , Yang Je Woo , Lee Kee‐Jung
Published: April 2009

Novel heterocycles, 4H‐tetrazolo[1,5‐a][1]benzazepines 6 were prepared by the intramolecular 1,3‐dipolar cycloaddition reaction of azidophenylcyanomethyl compounds 5. The latter were readily obtained from 2‐azidobenzaldehyde through the Baylis‐Hillman adducts 3 followed by acetylation to compounds 4 and nucleophilic substitution by cyanide to compounds 5.
Detection and characterization of group C rotavirus in Buenos Aires, Argentina, 1997–2003
Authors: Castello Alejandro A. , Argüelles Marcelo H. , Rota Rosana P. , Humphrey Charles D. , Olthoff Alicia , Gentsch Jon R. , Glass Roger I. , Glikmann Graciela , Jiang Baoming
Published: April 2009

The role of group C rotaviruses as a cause of diarrhea was examined among children <17 years of age admitted to a Hospital in a suburban area of Buenos Aires, Argentina between 1997 and 2003. A total of 1,579 fecal samples were screened for group A (RVA) and C (RVC) rotaviruses by two in‐house ELISA methods at Quilmes University (UNQ‐ELISA). Samples positive, doubtful and negative by RVC specific UNQ‐ELISA (n = 246) were examined further for RVC by another in‐house ELISA (CDC‐ELISA), electron microscopy, RT‐PCR, nested PCR, and Southern hybridization. Sensitivity, specificity, and predictive values for each test were determined. While the sensitivity was comparable for the nested PCR and CDC‐ELISA methods (82.5%), the molecular methods were slightly more specific. Poorly preserved particles were often seen in fecal samples, suggesting that degradation of RNA could be a factor influencing the performance of molecular methods. The incidence of RVC was estimated to be 3% without apparent differences among seasons. RVC infected patients had a significantly (P < 0.001) higher median age (6 years vs. 1 year) than those with RVA infection. Sequence of the RVC VP7 gene from six Argentinean strains and sequences reported previously in different countries showed high nucleotide (94.4–99.9%) sequence identities, indicating a high degree of conservation for human RVC VP7 genes among strains collected on five continents over a period of 17 years. These findings indicate that RVC is a significant cause of diarrhea and it is necessary to develop simple and sensitive serological methods for its detection. J. Med. Virol. 81:1109–1116, 2009. © 2009 Wiley‐Liss, Inc.
Amino acid substitutions in the hepatitis C virus core region of genotype 1b are the important predictor of severe insulin resistance in patients without cirrhosis and diabetes mellitus
Authors: Akuta Norio , Suzuki Fumitaka , Hirakawa Miharu , Kawamura Yusuke , Yatsuji Hiromi , Sezaki Hitomi , Suzuki Yoshiyuki , Hosaka Tetsuya , Kobayashi Masahiro , Kobayashi Mariko , Saitoh Satoshi , Arase Yasuji , Ikeda Kenji , Kumada Hiromitsu
Published: April 2009

Previous studies provided a direct experimental evidence for the contribution of HCV core protein in the development of insulin resistance (IR), but the clinical impact of HCV core region on IR is still not clear. The present study evaluated the impact of Amino acid (aa) substitutions of HCV‐1b core region on IR in 123 Japanese patients infected with HCV‐1b without cirrhosis and diabetes mellitus, and investigated the treatment efficacy of 48‐week pegylated interferon (PEG‐IFN) plus ribavirin (RBV) according to HOMA‐IR values. Patients with IR (HOMA‐IR ≥2.5) and severe IR (HOMA‐IR ≥3.5) were present in 51.2% and 27.6%, respectively. Multivariate analysis identified body mass index (≥25 kg/m2) and hepatocyte steatosis (≥5%) as significant determinants of IR. Furthermore, multivariate analysis identified hepatocyte steatosis (≥5%), aa substitutions of the core region (Gln70 (His70) and/or Met91), and age (≥55 years) as significant determinants of severe IR. Especially, significantly lower proportions of patients with Gln70 (His70) and/or Met91 were noted among those without severe IR (59.6%) than those with severe IR (82.4%). The rates of sustained virological response in patients with IR (50.0%) were not significantly different from those without IR (52.9%). Furthermore, the rates of non‐virological response in patients with IR (28.9%) were not significantly also different from those without IR (20.6%). In conclusion, the present study indicated that substitutions of HCV‐1b core region were the important predictor of severe IR in patients without cirrhosis and diabetes mellitus, but HOMA‐IR values might be not useful as predictors of 48‐week PEG‐IFN plus RBV therapy. J. Med. Virol. 81:1032–1039, 2009. © 2009 Wiley‐Liss, Inc.
Antiviral effect of nicotinamide on enterovirus‐infected human islets in vitro: Effect on virus replication and chemokine secretion
Authors: Moëll Annika , Skog Oskar , Åhlin Erik , Korsgren Olle , Frisk Gun
Published: April 2009

Type 1 diabetes is a chronic disease characterized by the selective destruction of insulin‐producing cells in the pancreas. Enterovirus (EV) is the prime candidate to initiate this destruction and several inflammatory chemokines are induced by EV infection. Nicotinamide has been shown to protect isolated human islets, and to modulate chemokine expression. The aim of this study was to evaluate the effect of nicotinamide on EV replication and EV‐induced chemokine secretion and cytolysis of human islets. Two EV strains were used to infect human islets in vitro, one lytic (Adrian) isolated from a child at onset of type 1 diabetes, and one non‐lytic (VD2921). Secretion of the chemokines IP‐10 and MCP‐1, viral replication, and virus‐induced cytopathic effect (CPE), were measured at different time points post‐infection. Addition of nicotinamide to the culture medium reduced viral replication and virus‐induced islet destruction/CPE, significantly. Both EV strains increased secretion of IP‐10 and MCP‐1, when measured days 2–3, and days 5–7 post infection, compared to mock‐infected control islets. IP‐10 was not produced by uninfected isolated islets, whereas a basal secretion of MCP‐1 was detected. Interestingly, addition of nicotinamide blocked completely (Adrian), or reduced significantly (VD2921), the virus‐induced secretion of IP‐10. Secretion of MCP‐1 was also reduced in the presence of nicotinamide, from infected and uninfected islets. The reported antiviral effects of nicotinamide could have implications for the treatment/prevention of virus‐ and immune‐mediated disease. Also, this study highlights a possible mechanism of virus‐induced type 1 diabetes through the induction of MCP‐1 and IP‐10 in pancreatic islets. J. Med. Virol. 81:1082–1087, 2009. © 2009 Wiley‐Liss, Inc.
Absence of genotypic drug resistance and presence of several naturally occurring polymorphisms of human immunodeficiency virus‐1 CRF06_cpx in treatment‐naive patients in Estonia
Authors: Avi Radko , Huik Kristi , Sadam Maarja , Karki Tonis , Krispin Tonu , Ainsalu Külliki , Paap Piret , Schmidt Jelena , Nikitina Natalia , Lutsar Irja
Published: April 2009

All non‐B HIV‐1 subtypes and circulating recombinant forms (CRFs) are characterized by several polymorphisms in protease (PR) region. In addition, in recent years the increasing use of antiretroviral treatment (ART) has rapidly raised the spread of transmitted drug resistance. We aimed to determine the presence of naturally occurring polymorphisms and transmitted drug resistance mutations (DRMs) in ART naïve HIV‐1‐positive subjects in Estonia. A total of 115 drug‐naive HIV‐1‐infected subjects (mean age 27 years; 70% male; 65% infected via intravenous drug use and 34% by heterosexual contact) were enrolled. Viral genomic RNA from plasma was directly sequenced in PR, revertase (RT), and envelope (env) regions. Phylogenetic analysis of RT and env regions revealed that 89% and 3% of sequenced viruses belonged to CRF06_cpx and subtype A1, respectively, and 6% were described as unique recombinants (signed A1‐06) between CRF06_cpx and subtype A1 viruses. No primary DRMs were found in PR or RT regions indicating the absence of transmitted drug resistance. The most common polymorphisms in the PR region were K14R, M36I, H69K, and L89M seen in 96%, 100%, 99%, and 100%, respectively. The clinical relevance of these polymorphisms in terms of success of ART has to be monitored in future clinical studies. J. Med. Virol. 81:953–958, 2009. © 2009 Wiley‐Liss, Inc.
Varying abilities of recombinant polypeptides from different regions of hepatitis E virus ORF2 and ORF3 to detect anti‐HEV immunoglobulin M
Authors: Ma Hongxia , Song Xiaoguo , Li Zhuo , Harrison Tim J. , Zhang Heqiu , Huang Weijin , Hao Wa , Kong Wei , Wang Youchun
Published: April 2009

Following infection with hepatitis E virus (HEV), anti‐HEV immunoglobulin (Ig) M is thought to develop before anti‐HEV IgG and to be a better marker for differentiating between the acute and convalescent phases of infection. In order to select polypeptides for improved detection of anti‐HEV IgM, six and three overlapping polypeptides from open reading frames (ORFs) 2 and 3, respectively, of HEV genotypes 1 and 4 were expressed as fusion proteins in Escherichia coli. The reactivities of the polypeptides with anti‐HEV IgM were evaluated using immunoblotting and enzyme immunoassays (EIAs). The data indicated that polypeptides from the N‐terminus of ORF3 and middle region of ORF2 were weakly or not reactive with anti‐HEV IgM, while those from the remaining regions of ORF2 and ORF3 contained reactive epitopes. Anti‐HEV IgM against the N‐ or C‐terminus of ORF2 appeared earlier and disappeared faster than that against polypeptides from the C‐terminus of ORF3, based on serum samples from rhesus monkeys infected experimentally, and from patients infected naturally, with HEV. The N‐ and C‐terminal polypeptides from ORF2 complemented one another in detecting anti‐HEV IgM and EIA sensitivity was improved significantly with a combination of these polypeptides. The reactivities of ORF2 polypeptides from genotypes 1 and 4 were similar but that of ORF3 differed with sera from monkeys infected by the two genotypes. Thus, a combination of N‐ and C‐terminal polypeptides of ORF2 from one genotype may be effective in EIAs to detect anti‐HEV IgM. J. Med. Virol. 81:1052–1061, 2009. © 2009 Wiley‐Liss, Inc.
Gene expression profiling by microarray analysis reveals an important role for caspase‐1 in dengue virus‐induced p53‐mediated apoptosis
Authors: Nasirudeen A.M.A. , Liu Ding Xiang
Published: April 2009

Recently, a dengue virus‐induced apoptosis p53‐ and mitochondria‐mediated were reported in human and animal cells. To understand further the underlying mechanisms, a p53‐deficient cell line, H1299, and a p53‐knockin cell line, H273, were infected with dengue type 1 virus and the cellular gene expression profiles at the mRNA level were analyzed by affymetrix array analysis. The results showed 183 genes with at least twofold increase at mRNA expression level in dengue virus‐infected cells. Among the 183 genes, 68 genes were up‐regulated in both H1299 and H273 cells and 78 genes were found to be up‐regulated in only H273 cells. Eleven selected genes, mainly involved in IFN‐pathway, cell cycle, signal transduction, and ubiquitin–proteasome pathways were confirmed using qualitative and quantitative PCR. Interestingly, an approximately 32‐fold increase in caspase‐1 expression was observed in the p53‐knockin cell line, H273. Gene silencing of caspase‐1 or inhibition of caspase‐1 activity led to reduction in dengue virus‐induced apoptosis with minimal effect on virus replication. J. Med. Virol. 81:1069–1081, 2009. © 2009 Wiley‐Liss, Inc.
Genetic variability of hepatitis C virus in South Egypt and its possible clinical implication
Authors: Elkady Abeer , Tanaka Yasuhito , Kurbanov Fuat , Sugauchi Fuminaka , Sugiyama Masaya , Khan Anis , Sayed Douaa , Moustafa Ghada , AbdEl‐Hameed AbdEl‐Rahman , Mizokami Masashi
Published: April 2009

Egypt is one of the countries with very high rates of hepatitis C virus (HCV) related morbidity and mortality. However, little is known about geographical and clinical differences in genetic variability of HCV in Egypt. Using direct sequencing and phylogenetic analysis of partial core/E1 and NS5B regions of the HCV genome, HCV genotype/subtype was determined in 129 HCV‐infected patients residing in three governates in south Egypt: Assuit, Sohag, and Qena. According to clinical stage of infection, patients were categorized into four groups: asymptomatic carriers, n = 16; chronic hepatitis C patients, n = 36; liver cirrhosis, n = 54; and hepatocellular carcinoma (HCC), n = 23. Genotype 4a was detected in 80.6%, whereas 1g, 4l, 4n, 4o, 4f, and 4m were identified in 7.7%, 4.7%, 3.9%, 1.6%, 0.8%, and 0.8% of cases, respectively. The prevalence of 4a differed regionally; from 88.5% (in Sohag) to 64% (in Assuit, P = 0.002). Genotypes 4l and 4n had a higher prevalence in Assuit (12.8%, 10.3%) than Sohag (0%, 0%; P ≤ 0.011). Difference in clinical features of determined genotypes/subtypes was observed; more carriers of non‐4a variants (4l and 4n, 4f, or 4m) had chronic hepatitis compared to carriers of 4a (53.3% vs. 23.1%, P = 0.025), while more patients with 4a had liver cirrhosis (45.2% vs. 13.3%, P = 0.023). Two HCV‐4o strains were isolated in this study, both from patients with HCC. In conclusion, geographical diversity of HCV was revealed in this study in southern Egypt. A further case–control study is required to confirm the trends of differential pathogenicity of HCV subtypes, indicated by this study. J. Med. Virol. 81:1015–1023, 2009. © 2009 Wiley‐Liss, Inc.
Effect of long‐term dietary administration of oregano and rosemary on the antioxidant status of rat serum, liver, kidney and heart after carbon tetrachloride‐induced oxidative stress
Authors: Botsoglou Nikolas A , Taitzoglou Ioannis A , Botsoglou Evropi , Zervos Ioannis , Kokoli Alexandra , Christaki Efterpi , Nikolaidis Efstathios
Published: April 2009

BACKGROUND: This study was performed on female Wistar rats allocated to eight groups of six animals each. Groups 1 and 2 were fed the basal diet, groups 3 and 4 were fed the basal diet supplemented with ground oregano at 20 g kg−1 level, groups 5 and 6 were fed the basal diet supplemented with ground rosemary at 20 g kg−1 level, while groups 7 and 8 were fed the basal diet supplemented with both oregano and rosemary, each at 20 g kg−1 level. Following 6 weeks feeding, groups 2, 4, 6 and 8 were injected with CCl4 at 1 mL kg−1 body weight, and 6 h thereafter all animals were sacrificed.

RESULTS: Administration of CCl4 to the control rats enhanced (P < 0.05) aspartate transaminase (AST), alanine transaminase (ALT) and alkaline phosphatase (ALP) activities, decreased cholesterol and triglycerides content in serum, increased (P < 0.05) lipid peroxidation and decreased (P < 0.05) the ABTS radical cation, the hydroxyl anion radical, the superoxide anion radical, and the hydrogen peroxide scavenging activities in all tested tissues, as compared to the control. Feeding oregano, rosemary or both before CCl4 treatment resulted in decline (P < 0.05) of the increase in AST, ALT and ALP activities, increase (P < 0.05) of cholesterol and triglycerides in serum, decrease (P < 0.05) of lipid peroxidation, and increase (P < 0.05) of the ABTS radical cation, hydroxyl anion radical, superoxide anion radical and hydrogen peroxide scavenging activity.

CONCLUSION: The results of this study suggest that long‐term dietary administration of oregano and rosemary has the potential to quench free radicals and alleviate CCl4‐induced oxidative stress in rats. Copyright © 2009 Society of Chemical Industry
Physical and sensory characteristics of processed cheeses manufactured by extrusion technology
Authors: Adhikari Koushik , Cole Andrea , Grün Ingolf , Heymann Hildegarde , Hsieh Fu‐Hung , Huff Harold
Published: April 2009

BACKGROUND: Not much work has been reported on use of extrusion technology for manufacturing processed cheese. The main goal of this study was to determine whether processed cheese of acceptable quality could be manufactured by extrusion technology. Two extrusion temperatures (80 and 90 °C), two moisture levels (440 and 480 g kg−1), and two emulsifying salt levels (10 and 15 g kg−1) were studied (eight experimental samples). Instrumental measures (moisture and texture profile analysis), descriptive analysis, and consumer acceptability for the processed cheese samples were carried out.

RESULTS: The instrumental measures and descriptive analysis showed differences among the samples. The major difference was a result of the moisture content. The lower‐moisture cheeses were firmer/chewier in texture, and had more Cheddar flavor note. Consumers found the lower‐moisture cheeses extruded at 80 °C to be more acceptable.

CONCLUSION: It could be concluded from this study that processed cheeses that were extruded at lower temperature with lower moisture levels might be better suited for manufacturing using extrusion technology. Copyright © 2009 Society of Chemical Industry
Lymph node involvement in ampullary cancer: The importance of the number, ratio, and location of metastatic nodes
Authors: Sierzega Marek , Nowak Krystyna , Kulig Jan , Matyja Andrzej , Nowak Wojciech , Popiela Tadeusz
Published: April 2009

Background and Objectives

Lymph node involvement significantly affects survival of cancer patients. The aim of this study was to evaluate the importance of the number, ratio, and location of metastatic lymph nodes in ampullary cancers.

Methods

Medical records of 111 patients who underwent curative pancreaticoduodenectomy for ampullary carcinomas were reviewed.

Results

Metastatic lymph nodes were found in 52 (47%) patients and the median number of involved nodes was 3 (95% confidence interval (CI) 3–4; range 1–17). In the univariate analysis, gender, type of pancreaticoduodenectomy, depth of tumor invasion, perineural invasion, presence of metastatic nodes, their number, and ratio of metastatic nodes significantly correlated with patient survival. However, the location of metastatic nodes did not influence survival among patients with nodal involvement. Only four or more metastatic nodes (relative risk 7.35, 95% CI 3.34–16.17) and tumor invasion of peripancreatic soft tissues (relative risk 5.00, 95% CI 1.20–20.92) were the independent prognostic factors in the multivariate analysis.

Conclusions

The number of metastatic nodes significantly affected patient survival. Although the location and ratio of metastatic nodes were not independent prognostic factors, these variables should be further evaluated with large‐scale population data sets. J. Surg. Oncol. 2009;100:19–24. © 2009 Wiley‐Liss, Inc.
Characterization of Star Adhesive Sealants Based On PEG/Dextran Hydrogels
Authors: Artzi Natalie , Shazly Tarek , Crespo Cristina , Ramos Adriana Bon , Chenault H. Keith , Edelman Elazer R.
Published: April 2009

Swellable PEG amine/dextran aldehyde composite materials are emerging as a controlled, biocompatible tissue adhesive. We explain how preservation of natural tissue amines provides biocompatibility for PEG/dextran that exceeds the stringent, destructive cyanide‐based chemistry of cyanoacrylates, and adhere far better than fibrin glue. Strategic variations of material composition allow for the improvement of biocompatibility and adhesion strength. Material variations can be tailored to match the needs of specific tissue beds for an array of clinical applications. PEG/dextran cohesive properties are most responsive to variations in the PEG component (number of arms and solid content), while tissue/material adhesion strength is primarily determined by the number of aldehydes in the dextran.

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Facile Access to Hydroxy‐Functional Core–Shell Microspheres via Grafting of Ethylene Oxide by Anionic Ring‐Opening Polymerization
Authors: Joso Raymond , Reinicke Stefan , Walther Andreas , Schmalz Holger , Müller Axel H. E. , Barner Leonie
Published: April 2009

We present a facile access route to hydroxy‐functional narrow disperse microspheres of well‐defined grafting density (GD). Ethylene oxide has been grafted from highly crosslinked poly(divinyl benzene) microspheres by anionic ring‐opening polymerization using sec‐butyllithium as activator together with the phosphazene base t‐BuP4. Initially, core microspheres have been prepared by precipitation polymerization utilizing divinyl benzene (DVB, 80 wt.‐%). The grafting of poly(ethylene oxide) (PEO) from the surface resulted in the formation of functional core–shell microspheres with hydroxy‐terminal end groups. The number average particle diameter of the grafted microspheres was 3.6 µm and the particle weight increased by 5.7%. The microspheres were characterized by SEM, FT‐IR spectroscopy, elemental analysis, and fluorescence microscopy. The surface GD (determined via two methods) was 1.65 ± 0.06 and 2.09 ± 0.08 chains · nm−2, respectively.

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Three‐dimensional multislice spiral computed tomographic angiography: A potentially useful tool for safer free tissue transfer to complicated regions
Authors: Demirtas Yener , Cifci Mehmet , Kelahmetoglu Osman , Demir Ahmet , Danaci Murat
Published: April 2009

Three‐dimensional multislice spiral computed tomographic angiography (3D‐MSCTA) is a minimally invasive method of vascular mapping. The aim of this study was to evaluate the clinical usefulness of this imaging technique in delineating the recipient vessels for safer free tissue transfer to complicated regions. 3D‐MSCTA was performed preoperatively in 26 patients scheduled for free tissue transfer, in whom the availability of the recipient vessels were considered to be uncertain, and 23 of these were operated on. Radiographic and operative findings regarding the availability of the recipient vessels for anastomosis were correlated in 21 of these 23 patients. 3D‐MSCTA yielded two false‐positive results; anastomosis was not possible because of widespread atherosclerotic plaques and poor flow observed in the recipient arteries despite the good caliber observed in 3D‐MSCTA images. 3D‐MSCTA provides a noninvasive means of preoperatively assessing recipient site vessels for anatomic variations and suitability before free tissue transfer and enables the surgeon to establish an appropriate treatment plan. But it is not 100% reliable yet and the possibility of false‐positive results should be kept in mind, especially inthe patients with peripheral vascular disease. 3D‐MSCTA has the potential to replace digital subtraction angiography for planning of microvascular reconstructions and newer devices with higher resolutions will probably increase the reliability of this technique. © 2009 Wiley‐Liss, Inc. Microsurgery, 2009.
Improved applicability of DOSY experiments by high resolution probes combined with gradient amplifiers of diffusion units
Authors: Zhang Hongxia , Kerssebaum Rainer , Gschwind Ruth M.
Published: April 2009

Short relaxation times and small diffusion coefficients often impede reliable diffusion experiments due to insufficient signal to noise ratios, especially in low temperature studies, where in the case of small diffusion coefficients in combination with very short T2 times and substantial convection, double‐stimulated‐echo experiments are required as last resort of convection‐compensating DOSY pulse sequences. Therefore, the combination of a strong gradient amplifier of a diffusion unit with Z‐gradient high resolution probes is tested for low temperature applications to combine the advantages of high 1H resolution, flexible temperature, and multinuclear applications with short gradient durations and diffusion delay. The experimental spectra on phosphoramidite ligands and phosphoramidite‐copper complexes show that signal to noise improvements up to 176% were achieved despite longer eddy current delays and increased noise levels. Calculational estimations of the enhancement factors predict special benefits for systems with short transversal relaxation times and small diffusion coefficients and promise even higher enhancement factors for noise level optimized combinations. In addition, an easy way is presented to find fast and effectively relaxation optimized DOSY parameters for the convection‐compensated double‐stimulated‐echo pulse sequence of Jerschow and Müller. Copyright © 2009 John Wiley & Sons, Ltd.
Theoretical investigation on multinuclear NMR chemical shifts of some tris(trifluoromethyl)boron complexes
Authors: Zhang Jun , Cai Shuhui , Chen Zhong
Published: April 2009

Tris(trifluoromethyl)boron complexes have unusual properties and may find applications in many fields of chemistry, biology, and physics. To gain insight into their NMR properties, the isotropic 11B, 13C, and 19F NMR chemical shifts of a series of tris(trifluoromethyl)boron complexes were systematically studied using the gauge‐included atomic orbitals (GIAO) method at the levels of B3LYP/6‐31 + G(d,p)//B3LYP/6‐31G* and B3LYP/6‐311 + G(d,p)//B3LYP/6‐311 + G(d,p). Solvent effects were taken into account by polarizable continuum models (PCM). The calculated results were compared with the experimental values. The reason that the structurally inequivalent fluorine atoms in a specific species give a same chemical shift in experimental measurements is attributed to the fast rotation of CF3 group around the BC(F3) bond because of the low energy barrier. The calculated 11B, 13C(F3), and 19F chemical shifts are in good agreement with the experimental measurements, while the deviations of calculated 13C(X, X = O, N) chemical shifts are slightly large. For the latter, the average absolute deviations of the results from B3LYP/6‐311 + G(d,p)//B3LYP/6‐311 + G(d,p) are smaller than those from B3LYP/6‐31 + G(d,p)//B3LYP/6‐31G*, and the inclusion of PCM reduces the deviation values. The calculated 19F and 11B chemical shieldings of (CF3)3BCO are greatly dependent on the optimized structures, while the influence of structural parameters on the calculated 13C chemical shieldings is minor. Copyright © 2009 John Wiley & Sons, Ltd.
Recovery of equilibrium on star patches using a partition of unity technique
Authors: Moitinho de Almeida J. P. , Maunder E. A. W.
Published: April 2009

A technique for recovering equilibrated element stresses is developed for finite element models of structural mechanics problems. The data for the method consist of the prescribed loading and the stress and displacement fields resulting from a conventional compatible finite element model. Local problems are defined for each star of elements, via the introduction of fictitious body forces and strains. These problems can be solved independently for equilibrium in a process that can be easily parallelized. The quality of the solutions is assessed, for two‐dimensional linear elastic problems, by using them to compute bounds of the error of the finite element solutions, in terms of both global and local quantities of interest. Copyright © 2009 John Wiley & Sons, Ltd.
Altered expression of MUTYH and an increase in 8‐hydroxydeoxyguanosine are early events in ulcerative colitis‐associated carcinogenesis
Authors: Gushima Masaki , Hirahashi Minako , Matsumoto Takayuki , Fujita Kouhei , Fujisawa Ritsuko , Mizumoto Kazuhiro , Nakabeppu Yusaku , Iida Mitsuo , Yao Takashi , Tsuneyoshi Masazumi
Published: April 2009

8‐Hydroxy‐guanine (8‐OH‐G) mismatches readily with adenine residues, leading to a G : C to T : A transversion mutation. The human mutY homologue (MUTYH) excises adenine misincorporated opposite 8‐OH‐G during replication and suppresses mutations caused by reactive oxygen species. We defined the expression of 8‐hydroxydeoxyguanosine (8‐OHdG) and MUTYH in ulcerative colitis (UC)‐associated neoplasia by immunohistochemistry and compared this with expression in UC patients without neoplasia and patients unaffected by UC. We also performed mutation analyses for MUTYH and K‐ras. 8‐OHdG was expressed more intensely in the mucosa of UC‐associated neoplasia and UC without neoplasm than in the mucosa unaffected by UC. Immunohistochemistry with two different types of MUTYH antibody showed that UC‐associated neoplasia and UC without neoplasia exhibited strong cytoplasmic expression and attenuated nuclear expression of MUTYH when compared with patients unaffected by UC. No pathological MUTYH mutations were detected in any of the UC‐associated neoplasia cases. However, K‐ras mutation was detected in two cases, one of which showed G : C to T : A transversion mutation and attenuated nuclear staining of MUTYH. In conclusion, inflamed mucosa of UC is exposed to oxidative damage. An increase in cytoplasmic MUTYH, rather than its mutation, may contribute to the promotion of carcinogenesis in UC. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Synthetic popularity reflects chemical reactivity
Authors: Kowalczyk Bartlomiej , Bishop Kyle J. M. , Smoukov Stoyan K. , Grzybowski Bartosz A.
Published: April 2009

Large and diverse databases of chemical reactions contain statistically significant information about the propensities of molecules to undergo specific chemical transformations. It is shown that this information can be quantified to reflect reaction thermodynamics/kinetics and can be used to construct primitive (yet accurate) reactivity indices from the counts of reported reactions involving molecules/molecular positions of interest. These indices correlate with frontier orbital (FO) populations or Hammettσandρparameters for a range of reactions involving aromatic substrates. These findings suggest that large chemical databases are not only a historical repository of chemical knowledge but also tools with which one can make useful chemical predictions. Copyright © 2009 John Wiley & Sons, Ltd.
A DFT/TD‐DFT study for the ground and excited states of peramine and some pyrrolopyrazinone compounds
Authors: Łapiński Andrzej , Dubis Alina T.
Published: April 2009

Peramine, a heterocyclic natural molecule, reveals two main, different in nature, electronic absorption bands. Theoretical calculations at the TD‐B3LYP/6–311++G(d,p) level of theory show that the electronic excitations are connected predominantly with π → π* and charge‐transfer (CT) transitions. Excitation of electrons from the pyrrolopyrazinone ring to the side chain plays a role in creating the CT transition. The character and energy of the first 30 singlet–singlet electronic transitions have also been investigated for the most stable conformation of peramine. Copyright © 2009 John Wiley & Sons, Ltd.
Fluticasone propionate/salmeterol and exercise‐induced asthma in children with persistent asthma
Authors: Pearlman David , Qaqundah Paul , Matz Jonathan , Yancey Steven W. , Stempel David A. , Ortega Hector G.
Published: April 2009

Rationale

Exercise is a common trigger in children with persistent asthma and inhaled corticosteroids have been shown to effectively treat clinical manifestations of persistent asthma, including protection from decrements in lung function caused by exercise. The goal of this study was to evaluate the effectiveness of fluticasone propionate/salmeterol 100/50 mcg compared with fluticasone propionate 100 mcg for the prevention of airflow limitation triggered by standardized exercise challenge in pediatric and adolescent patients with persistent asthma.

Methods

Multicenter, randomized, double‐blind, parallel group trial of 248 subjects with persistent asthma (age 4–17 years) randomized to receive fluticasone propionate/salmeterol (100/50 mcg twice daily) or fluticasone propionate alone (100 mcg twice daily) via Diskus for 4 weeks. Exercise challenge tests were performed during screening and approximately 8 hr after administration of the blinded study medication on Treatment Day 28.

Results

After 4 weeks of therapy both treatments provided protection following exercise challenge. The protection estimated by the maximal fall in FEV1 was significantly better for fluticasone propionate/salmeterol (9.5 ± 0.8% [mean ± SE]) compared with fluticasone propionate alone (12.7 ± 1.1%, P = 0.021). Statistically significant differences were not observed for asthma rescue‐free days and asthma symptom‐free days.

Conclusion

Chronic dosing with fluticasone propionate/salmeterol in a single device provides superior protection compared with an inhaled corticosteroid alone in protecting against exercise‐induced asthma in children with persistent asthma. Pediatr Pulmonol. 2009; 44:429–435. © 2009 Wiley‐Liss, Inc.
Predicting changes in clinical status of young asthmatics: Clinical scores or objective parameters?
Authors: Leung Ting F. , Ko Fanny W.S. , Wong Gary W.K. , Li Chung Y. , Yung Edmund , Hui David S.C. , Lai Christopher K.W.
Published: April 2009

Preventing asthma exacerbation is an important goal of asthma management. The existing clinical tools are not good in predicting asthma exacerbations in young children. Childhood Asthma Control Test (C‐ACT) was recently published to be a simple tool for assessing disease control in young children. This study investigated C‐ACT and other disease‐related factors for indicating longitudinal changes in asthma status and predicting asthma exacerbations. During the same clinic visit, asthma patients aged 4–11 years completed the Chinese version of C‐ACT and underwent exhaled nitric oxide and spirometric measurements. Blinded to these results, the same investigator assigned Disease Severity Score (DSS) and rated asthma control according to Global Initiative for Asthma. Asthma exacerbations during the next 6 months were recorded. Ninety‐seven patients were recruited, with their mean (standard deviation [SD]) age being 9.2 (2.0) years. Thirty‐six (37.1%) patients had uncontrolled asthma at baseline. C‐ACT, DSS, and FEV1 differed among patients with different control status (P < 0.001 for C‐ACT and DSS; P = 0.028 for FEV1). Thirty‐two patients had asthma exacerbations during the 6‐month follow‐up. Changes in patients' C‐ACT scores correlated with changes in asthma control status, DSS, and FEV1 (P = 0.019, 0.034, and 0.020, respectively). C‐ACT score was lower among patients with asthma exacerbations (mean [SD]: 22.9 [4.2] vs. 24.5 [2.1]; P = 0.015). Logistic regression confirmed that the occurrence of asthma exacerbations was associated only with baseline C‐ACT (B = −0.203, P = 0.042). In conclusion, C‐ACT is better than DSS and objective parameters in reflecting changes in asthma status and predicting asthma exacerbations in young children. Pediatr Pulmonol. 2009; 44:442–449. © 2009 Wiley‐Liss, Inc.
UV properties of 𝒩 = 8 supergravity
Authors: Kallosh R.
Published: April 2009

We discuss here the recent developments in 𝒩 = 8 supergravity. In particular, we propose to use the light‐cone superspace with an unconstrained chiral scalar superfield for the studies of the UV structure of the perturbative 𝒩 = 8 supergravity. For this purpose we construct the generating functional for the light‐cone momentum space superfield amplitudes. We prove an 𝒩 = 8 equivalence theorem for the light‐cone and covariant on‐shell amplitudes. We point out an interesting relation between our light‐cone formalism and Nair' s construction and supertwistors. We also point out the importance of the non‐linearly realized E(7,7), symmetry for these studies and argue that this symmetry may be anomaly‐free.
Gravity as the square of Yang‐Mills: implications for 𝒩 = 8 supergravity
Authors: Ananth S.
Published: April 2009

The pure gravity Lagrangian can be written as the “square” of the pure Yang‐Mills Lagrangian to second order in coupling constants. This paper uses this form of the gravity Lagrangian as a starting point to arrive at a compact light‐cone superspace Lagrangian for 𝒩 = 8 supergravity to order κ2.
Low thermal resistance, high‐speed 980 nm asymmetric intracavity‐contacted oxide‐aperture VCSELs
Authors: Song Y. M. , Chang K. S. , Na B. H. , Yu J. S. , Lee Y. T.
Published: April 2009

We demonstrated high‐speed characteristics of an oxide‐aperture vertical‐cavity surface‐emitting laser (VCSEL) with intracavity structures for both p‐ and n‐contacts, based on InGaAs/GaAs multiple quantum wells operating at λ ∼ 980 nm, indicating a low thermal resistance (Rth). The asymmetric current injection scheme is employed for reducing current crowding around the rim of the oxide aperture. A high aluminium content undoped Al0.88Ga0.12As and GaAs distributed Bragg reflector (DBR) mirror is used for efficient heat dissipation. The VCSEL with a 7 μm oxide aperture exhibited an output power of 2.5 mW and a threshold current of 0.8 mA with a slope efficiency of 0.39 mW/mA at 20 °C under continuous‐wave operation and it still worked with 1.3 mW at 90 °C. The temperature tuning coefficient of 0.081 nm/°C and dissipated electrical power tuning coefficient of 0.104 nm/mW were observed, leading to a low Rth of 1.28 °C/mW. A high modulation bandwidth up to 13 GHz with a modulation current efficiency factor of 6.1 GHz/mA1/2 was achieved. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ray‐tracing study of Bragg diffraction‐assisted light extraction efficiency of GaN‐based light‐emitting diodes with vertical sidewalls
Authors: Liu Wen‐de , Gan Zi‐zhao
Published: April 2009

Ray‐tracing method is used to investigate the light extraction efficiency (LEE) of Bragg diffraction‐assisted GaN‐based light‐emitting diodes (LED's) with vertical sidewalls. The ray tracing is based on the analytical formulae of the LEE in the incoherent regime for LED model with infinite lateral size. It is shown that without considering the sidewalls, the change of the LEE with the absorption or backside reflectivity is too small and thus not reasonable. And the enhancement with respect to the unpatterned case could be overestimated by ignoring the finite‐size effect. Numerical calculations show that the enhancement of the LEE due to the sidewalls when compared to the infinite model could be up to 10% or even higher. Besides, the extracted energy from the sidewalls decreases due to the increased extraction from the PhC when compared to the unpatterned LED. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Strain effects and phonon–plasmon coupled modes in Si‐doped AlN
Authors: Gómez‐Gómez M. , Cros A. , Hermann M. , Stutzmann M. , Eickhoff M.
Published: April 2009

The E2h and A1(LO) phonon modes of AlN films grown on sapphire are analyzed by Raman scattering as a function of silicon doping for concentrations covering from 5.5 × 1019 cm–3 to 5.2 × 1021 cm–3. For high doping levels the appearance of a mode around 520 cm–1 indicates the precipitation of crystalline silicon in the samples and its inhomogeneous incorporation to the AlN layer. The frequency of this mode shifts to lower energies with doping, indicating that the silicon crystals are embedded in the AlN lattice and under tensile strain. On the other hand, the AlN phonon modes are blue‐shifted due to the compressive strain as a result of the silicon incorporation. This strain is partially relieved for very high doping levels. The coupling of the polar A1(LO) mode of the AlN films with the electronic cloud (phonon–plasmon coupling) is analyzed for electron concentrations up to 4 × 1017 cm–3. A 2 cm–1 blue shift of the phonon frequencies is observed for the highest electron concentrations. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
UV emission on a Si substrate: Optical and structural properties of γ‐CuCl on Si grown using liquid phase epitaxy techniques
Authors: Cowley A. , Foy B. , Danilieuk D. , McNally P. J. , Bradley A. L. , McGlynn E. , Danilewsky A. N.
Published: April 2009

Considerable research is being carried out in the area of wide band gap semiconductor materials for light emission in the 300–400 nm spectral range. Current materials being used for such devices are typically based on II–VI and III‐nitride compounds and variants thereof. However, one of the major obstacles to the successful fabrication of III‐N devices is lattice mismatch‐induced high dislocation densities for epitaxially grown layers on non‐native substrates. γ‐CuCl is a direct bandgap material and an ionic wide bandgap I–VII semiconductor with a room temperature free exciton binding energy of ∼190 meV (compared to ∼25 meV and ∼60 meV for GaN and ZnO, respectively) and has a band gap of 3.4 eV (λ ∼ 366 nm). The lattice constant of γ‐CuCl (0.541 nm) is closely matched to that of Si (0.543 nm). This could, in principle, lead to the development of optoelectronic systems based on CuCl grown on Si. Research towards this end has successfully yielded polycrystalline γ‐CuCl on Si(100) and Si(111) using vacuum‐based deposition techniques [1]. We report on developments towards achieving single crystal growth of CuCl from solution via Liquid Phase Epitaxy (LPE) based techniques. Work is being carried out using alkali halide flux compounds to depress the liquidus temperature of the CuCl below its solid phase wurtzite‐zincblende transition temperature (407 °C [2]) for solution based epitaxy on Si substrates. Initial results show that the resulting KCl flux‐driven deposition of CuCl onto the Si substrate has yielded superior photoluminescence (PL) and X‐ray excited optical luminescence (XEOL) behavior relative to comparitively observed spectra for GaN or polycrystalline CuCl. This enhancement is believed to be caused by an interaction between the KCl and CuCl material subsequent to the deposition process, perhaps involving a reduction in Cl vacancy distributions in CuCl. This paper presents a detailed discussion of a CuCl LPE growth system as well as the characterization of deposited materials using X‐ray diffraction (XRD), room temperature and low temperature PL, and XEOL. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Microscopic description of strain‐reducing chemical bonding self‐organizations in non‐crystalline alloys
Authors: Lucovsky Gerald , Phillips James C.
Published: April 2009

Alloy compositions for a first transition (1) into, and a second transition (2) out of intermediate phases (IPs) have been identified (i) by Boolchand and co‐workers in bulk glasses, primarily by low values for the change in enthalpy, ΔHnr, for non‐reversible heat flow at the glass transition temperature, and (ii) by Lucovsky and coworkers in deposited thin film by combining spectrographic and electrical studies. This paper emphasizes chemical bonding self‐organizations that minimize macroscopic strain within IP windows, identifying necessary and sufficient conditions for IP windows to open, and to close. Percolation theory, competitive and synergistic double percolation, provide a framework for determining alloy compositions for the first and second transitions of IP windows in bulk glasses and thin films as well. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Controlled chemical phase separation in binary and ternary composites: A pathway to isotropic optical and electrical behavior for device applications
Authors: Lucovsky Gerald
Published: April 2009

There are many applications for nanocrystalline thin films in optical devices that require isotropic optical properties. A novel way to obtain these isotropic properties for the index of refraction and/or optical absorption constant, etc., and at the same time to minimize microscopic strain is presented in this article. This approach is based on strain reduction mechanisms that occur in the intermediate phases, IPs, of non‐crystalline glasses and thin films. In these compositional regimes, either site percolation, or volume percolation, each above an applicable critical value, provides a quantitative understanding of the microscopic bonding arrangements associated with strain‐reducing chemical bonding self‐organizations. A similar framework, presented for the first time in this article, develops a microscopic understanding of macroscopic strain reduction in several different phase‐separated composites. This understanding has emerged from focussed research on qualitatively different hetero‐structure device structure constituents, e.g.; (i) high‐k replacement dielectrics for SiO2 in field effect transistors gate stacks for advanced semiconductor devices, and (ii) active and passive thin films for optically switched memory cells. In each instance strain reduction and its intrinsic relationship to low densities of defects and defect precursors has provided a driving force in the identification of a narrow range of compositions that satisfy technological needs. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermopiezoelectric effects on optoelectronic properties of CdTe/ZnTe quantum wires
Authors: Patil Sunil R. , Melnik R. V. N.
Published: April 2009

We investigate thermopiezoelectric field distributions and their effects on electronic properties of the highly strained CdTe/ZnTe quantum wires. The full 3D coupled thermoelectromechanical formulation, consisting of balance equations for heat transfer, electrostatics and the mechanical field, is developed. Effects of thermal loadings on piezoelectric fields are determined for rectangular CdTe/ZnTe quantum wire systems. The conduction band edge shifts due to thermoelectromechancial loadings are calculated. A single band Schrödinger equation is used to determine eigenstates for electrons and the analysis of classical effects are presented. Piezoelectric quantities are observed to be relatively less sensitive to thermal loadings. However, these effects are observed to be important in the determination of electronic/optoelectronic properties of quantum wire systems. The results presented here help improve our understanding of the classical effects on electronic structures and optoelectronic properties of CdTe/ZnTe quantum wires. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Recombination processes and light‐induced defect creation in hydrogenated amorphous silicon
Authors: Morigaki K.
Published: April 2009

Recombination processes of electrons and holes in hydrogenated amorphous silison (a‐Si:H) are reviewed in terms of our model. The long decay component of photoluminescence (PL) and the long decay of light‐induced electron spin resonance (LESR) are compared, and it is concluded that radiative centres responsible for the long decay component of PL are not LESR centres that are nonradiative centres. This is consistent with our model. The mechanism of light‐induced defect creation in a‐Si:H and its kinetics is summarized in terms of our model. The related defects involved in the recombination processes and the light‐induced defect creation in a‐Si:H are discussed. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Preparation and luminescent properties of Eu2+‐activated glass ceramic phosphor precipitated with β‐Ca2SiO4 and Ca3Si2O7
Authors: Nakanishi Takayuki , Tanabe Setsuhisa
Published: April 2009

Eu2+: calcium silicate glass ceramics (GC) containing β‐Ca2SiO4 and Ca3Si2O7 crystal phosphors were fabricated by cerammization process from a GC that were prepared by a novel GC preparation; frozen sorbet method. The GC obtained (as‐made GC) consisted of glass and spherical β‐Ca2SiO4 crystal phases with size of about 20–40 μm. After post‐ceramization, Ca3Si2O7 crystals were also precipitated. Judging from the cathodoluminescence (CL) mapping images, two emission bands peaked at 515 nm and 600 nm were observed from different parts in the GC. The observed photoluminescence (PL) have two broad emission bands at 515 nm from Eu2+: β‐Ca2SiO4 and at 600 nm from Eu2+:Ca3Si2O7. With increasing heat‐treatment temperature, the color coordinates shifted from green range to center region, which corresponds to pure white in the CIE chromaticity diagram. Eu2+ doped calcium silicate GC containing β‐Ca2SiO4 and Ca3Si2O7 are suitable phosphor as the use of phosphor converting white light emitting diode (pc‐wLED) with high color rendering. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)