bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enantioselective analysis of propranolol and 4‐hydroxypropranolol by CE with application to biotransformation studies employing endophytic fungi
Authors: Borges Keyller Bastos , Pupo Mônica Tallarico , Bonato Pierina Sueli 
Published: October 2009

AbstractA CE method is described for the enantioselective analysis of propranolol (Prop) and 4‐hydroxypropranolol (4‐OH‐Prop) in liquid Czapek medium with application in the study of the enantioselective biotransformation of Prop by endophytic fungi. The electrophoretic conditions previously optimized were as follows: an uncoated fused‐silica capillary, 4% w/v carboxymethyl‐β‐CD in 25 mmol/L triethylamine/phosphoric acid (H3PO4) buffer at pH 9 as running electrolyte and 17 kV of voltage. UV detection was carried out at 208 nm. Liquid–liquid extraction using diethyl ether: ethyl acetate (1:1 v/v) as extractor solvent was employed for sample preparation. The calibration curves were linear over the concentration range of 0.25–10.0 μg/mL for each 4‐OH‐Prop enantiomer and 0.10–10.0 μg/mL for each Prop enantiomer (r≥0.995). Within‐day and between‐day relative standard deviations and relative errors for precision and accuracy were lower than 15% for all the enantiomers. Finally, the validated method was used to evaluate Prop biotransformation in its mammalian metabolite 4‐OH‐Prop by some selected endophytic fungi. The screening of five strains of endophytic fungi was performed and all of them could biotransform Prop to some extent. Specifically,Glomerella cingulata(VA1) biotransformed 47.8% of (−)‐(S)‐Prop to (−)‐(S)‐4‐OH‐Prop with no formation of (+)‐(R)‐4‐OH‐Prop in 72 h of incubation.
On‐line combination of CE and microscopy: An insight into the migration of microorganisms
Authors: Petr Jan , Ryparová Olga , Znaleziona Joanna , Maier Vítězslav , Ševčík Juraj 
Published: October 2009

AbstractIdentification of microbial contamination by CE has interested many researchers mainly because of the high speed of CE analysis. However, the CE separation of such big structures brings a lot of questions mainly about the behavior of microorganisms and about the mechanism of separation. In this work, we constructed a simple apparatus where a microscope was used as one detector and a UV detector was used as the second one and we made the comparison of three typical setups for CE of microorganisms. Saccharomyces cerevisiae was chosen as a model microorganism and was analyzed in bare fused‐silica capillaries, covalently modified capillaries and dynamically modified capillaries by poly(ethylene oxide) or CTAB. Results showed that the use of CE instrument directly connected with a microscope could be advantageous for the study of separation mechanisms and/or migration behavior.
Estimation and testing of portfolio Value‐at‐Risk based on L‐comoment matrices
Authors: Liu Wei‐Han 
Published: October 2009

AbstractThis study employs L‐comoments introduced by Serfling and Xiao (2007) into portfolio Value‐at‐Risk estimation through two models: the Cornish–Fisher expansion (Draper, N. R. & Tierney, D. E., 1973) and modified VaR (Zangari, P., 1996). Backtesting outcomes indicate that modified VaR outperforms and L‐comoments give better estimates of portfolio skewness and excess kurtosis than do classical central moments in modeling heavy‐tailed distributions. © 2009 Wiley Periodicals, Inc. Jrl Fut Mark 30:897–908, 2010
A new synthesis of alkane and polyfluoroalkanesulfonyl chlorides
Authors: Benfodda Zohra , Guillen Franck , Arnion Hélène , Dahmani Abdelkader , Blancou Hubert 
Published: October 2009

AbstractThis study describes a new and advantageous procedure for the synthesis of alkanesulfonyl chlorides (2) by the reaction of alkyl thiocyanates (1) with sulfuryl chloride in a mixture of acetic acid and water. The alkanesulfonyl chlorides were obtained in good yields. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:355–361, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20559
Allelic loss of chromosomes 8 and 19 in MENX‐associated rat pheochromocytoma
Authors: Shyla Alena , Hölzlwimmer Gabriele , Calzada‐Wack Julia , Bink Karin , Tischenko Oleg , Guilly Marie‐Noëlle , Chevillard Sylvie , Samson Elenore , Graw Jochen , Atkinson Michael J. , Pellegata Natalia S. 
Published: October 2009

AbstractPheochromocytomas are neoplasias of neural crest origin that arise from the chromaffin cells of the adrenal medulla. Pheochromocytomas arise with complete penetrance in rats homozygous for a germ‐line frameshift mutation of Cdkn1b, encoding the cell cycle inhibitor p27KIP1 (MENX syndrome). We performed a genome‐wide scan for allelic imbalance comparing 20 rat pheochromocytoma DNAs with normal rat DNA to better understand the pathobiology of the tumors and to correlate the findings with human pheochromocytoma. We identified allelic imbalance (AI) at candidate regions on rat chromosomes 8 and 19. Interestingly, the regions often lost in rat tumors are syntenic to regions involved in human pheochromocytomas. Fluorescence in situ hybridization analysis further validated the AI data. Sdhd and Rassf1a were analyzed in detail as they map to regions of AI on chromosome 8 and their homologues are implicated in human pheochromocytoma: we found no genetic mutations nor decreased expression. We also analyzed additional candidate genes, that is, rat homologues of genes predisposing to human pheochromocytoma and known tumor‐suppressor genes, but we found no AI. In contrast, we observed frequent overexpression of Cdkn2a and Cdkn2c, encoding the cell cycle inhibitors p16INK4a and p18INK4c, respectively. The relative small number of allelic changes we found in rat pheochromocytoma might be related to their nonmalignant status and losses at chromosomes 8 and 19 are events that precede malignancy. Because of the high concordance of affected loci between rat and human tumors, studies of the MENX‐associated pheochromocytomas should facilitate the identification of novel candidate genes implicated in their human counterpart.
Phosphatidylinositol 4,5‐bisphosphate‐specific AKT1 is oncogenic
Authors: Dannemann Nadine , Hart Jonathan Ross , Ueno Lynn , Vogt Peter K. 
Published: October 2009

AbstractThe protein kinase AKT1 (v‐akt murine thymoma viral oncogene homolog 1), also referred to as protein kinase B (PKB), is an essential mediator of the phosphatidylinositol 3‐kinase signaling pathway. Elevated activity of AKT1 is common in human cancer. Localization at the plasma membrane, leading to enhanced phosphorylation and activation of AKT1, is an important factor determining the oncogenicity of this kinase. Although the phosphatidylinositol 3‐kinase signaling pathway is frequently upregulated in cancer, cancer‐specific mutations in AKT1 are not common. Recently, such a mutation has been identified in breast, colon and ovarian cancers. The mutation is located in the pleckstrin homology (PH) domain of AKT1 and results in a glutamic acid to lysine substitution at residue 17. The resultant change in the conformation of the PH domain facilitates membrane binding of the mutant protein. Here we show that exchange of the PH domain leading to preferential binding of phosphatidylinositol 4,5‐bisphosphate (PIP2) over phosphatidylinositol 3,4,5‐trisphosphate (PIP3) constitutively activates AKT1. AKT1 with this altered PIP affinity induces oncogenic transformation in cultures of chicken embryo fibroblasts and causes neoplastic growth and angiogenesis in the chorioallantoic membrane of the chicken embryo. Gain‐of‐function mutants of AKT1 may not be affected by PI3K inhibitors that are currently in development. Therefore, AKT1 remains a distinct and important cancer target.
Dietary patterns and gastric cancer in a Portuguese urban population
Authors: Bastos Joana , Lunet Nuno , Peleteiro Bárbara , Lopes Carla , Barros Henrique 
Published: October 2009

AbstractDietary patterns analysis is a powerful technique to study the relations between diet and cancer. We aimed to quantify the association between dietary patterns and gastric cancer, by location and histological type, according to Helicobacter pylori infection status. We analyzed 591 incident cases of gastric adenocarcinoma and 1,463 community controls. Dietary intake was assessed using a validated food frequency questionnaire. Principal components and cluster analyses were used to define dietary patterns. Anti‐H. pylori IgG was assessed by ELISA. Age‐, gender‐, education‐ and total energy intake‐adjusted odds ratios (OR) were computed. Three dietary patterns were identified, with the following main characteristics: (I) high consumption of fruits and dairy products, and low consumption of alcoholic beverages; (II) low consumption of fruit, salads, vegetables, dairy products, fish and meat; (III) high consumptions of most food groups and low vegetable soup intake. Compared to pattern I, the risk of gastric cancer was higher for pattern II (OR = 1.68, 95% CI: 1.31–2.14) but not for pattern III (OR = 0.80, 95% CI: 0.57–1.14), with no effect modification by H. pylori infection. The association was similar for cardia and non‐cardia gastric cancer, but for tumors of the diffuse Laurén histological type, the association was weaker for pattern II vs. I (OR = 1.32, 95% CI: 0.83–2.08) and a protective effect was observed for pattern III vs. I (OR = 0.43, 95% CI: 0.22–0.87). Our results confirm the protective effect of high fruit and vegetables intake, and show a differential association according to histological type. No effect modification by H. pylori infection was observed.
miRNA control of tumor cell invasion and metastasis
Authors: Baranwal Somesh , Alahari Suresh K. 
Published: October 2009

AbstractMicroRNAs have emerged as a novel class of noncoding RNAs that regulate gene expression at the post‐translational level in almost every biological event. A large body of evidence indicates that microRNAs regulate the expression of different genes that play an important role in cancer cell invasion, migration and metastasis. In this review, we briefly describe the role of various miRNAs in invasion, migration and metastasis which are essential steps during cancer progression.
Thrombotic microangiopathy during peripheral blood stem cell mobilization
Authors: Naina Harris V.K. , Gertz Morie A. , Elliott Michelle A. 
Published: October 2009

AbstractGranulocyte colony‐stimulating factor (GCSF) is currently the most widely used cytokine for stem cell mobilization. There are few studies suggesting GCSF administration may induce activation of both coagulation and endothelial cells that could favor the developing of thrombotic events. We report a 58‐year‐old female with vasculitis and renal impairment. She was found to have an underlying monoclonal gammopathy of unknown significance (MGUS). The monoclonal protein was felt to play a role in her underlying renal disease and peripheral neuropathy. She was considered a candidate for peripheral blood stem cell transplantation to manage the monoclonal protein. During stem cell mobilization with GCSF, she developed worsening of anemia; thrombocytopenia and worsening of renal function. She was diagnosed with thrombotic microangiopathy (TMA) which was successfully treated with therapeutic plasma exchange and rituximab. It is possible that GCSF may have directly (activating endothelial cells) or indirectly (activation of underlying autoimmune disorder) contributed to TMA in this patient. J. Clin. Apheresis 2009. © 2009 Wiley‐Liss, Inc.
Genome modification in human embryonic stem cells
Authors: Tenzen Toyoaki , Zembowicz Filip , Cowan Chad A. 
Published: October 2009

AbstractInduced pluripotent stem cell (iPSC) technology has emerged as the most promising method for generating patient‐specific human embryonic stem (ES) cells and adult stem cells (Takahashi et al., 2007, Cell 131:861–872; Wernig et al., 2007, Nature 448:318–324; Park et al., 2008, Nature 451:141–146). So far, most studies of direct reprogramming have been done by using lentiviruses/retroviruses encoding the reprogramming factors. This represents a major limitation to therapeutic applications since viral integration in the host genome increases the risk of tumorigenicity, and low‐level residual expression of reprogramming factors may alter the differentiation potential of the human iPSCs (hiPSCs). As a result, more attention has been paid to developing new techniques to manipulate the human genome, with the goal of making safer hiPSCs that have fewer or no lesions or alterations in the genome. Additionally, the efficiency of reprogramming and of homologous recombination in gene therapy must be improved, if iPSC technology is to be a viable tool in regenerative medicine. Here, we summarize the recent developments in human genome manipulation for generating hiPSCs and advances in homologous recombination for gene targeting. J. Cell. Physiol. 222: 278–281, 2010. © 2009 Wiley‐Liss, Inc.
Quick and efficient method for genetic transformation of biopolymer‐producing bacteria
Authors: Wang Qin , Mueller Alexander P. , Leong Chean Ring , Matsumoto Ken'ichiro , Taguchi Seiichi , Nomura Christopher T. 
Published: October 2009

AbstractIn order to genetically modify microorganisms capable of producing polyhydroxyalkanoate (PHA) biopolymers, a simple and rapid method to prepare freshly plated Pseudomonas cells for transformation via electroporation was developed. This method can be used to transfer both replicative plasmids and linear DNA to knock out genes into the cells. The transformation efficiencies were in the range of ≥107 transformants µg−1 DNA for replicative plasmids and ≥106 transformants µg−1 DNA for linear DNA, which are comparable with commercially available competent cells. Furthermore, this transformation procedure can be performed in less than 10 min, saving a great deal of time compared with traditional methods. Knockout mutants of several Pseudomonas species were generated by transformation of linear DNA and these mutations were verified by PCR and analysis of PHA content. Copyright © 2009 Society of Chemical Industry
Long‐term survivors of esophageal cancer: Disease‐specific quality of life, general health and complications
Authors: Gockel I. , Gönner U. , Domeyer M. , Lang H. , Junginger Th. 
Published: October 2009

AbstractIntroductionThe aim of our study was to assess the quality of life as well as secondary cancers/diseases and esophagectomy‐related or unrelated interventions in the long‐term course of surgery.Patients and MethodsOut of 417 patients who underwent esophageal resection for cancer between September 1985 and November 2003, 85 were defined as long‐term survivors (≥5 years). Fifty patients still alive in November 2008 complied with our inclusion criteria. The general (QLQ‐C 30, version 3.0) as well as the esophagus specific quality of life (QLQ‐OES 18) were analyzed with the help of the EORTC QLQ‐questionnaires.ResultsThe median observation interval since the operation was 100.1 (range 60–238) months. A median Global Health Status of quality of life (EORTC QLQ‐C 30) of 66.7 was found (range 16.7–100). Among the functioning scores, emotional (83.3 (range 16.7–100)) and cognitive functioning (83.3 (range 0–100)) were highest. The esophagus‐specific quality of life (EORTC QLQ‐OES 18) revealed a median value (scale 0–100) of 0 each for dysphagia and difficulties with swallowing saliva, whilst reflux was a major problem with a score of 50.0 (range 0–100).ConclusionOur results show that long‐term survival with a good quality of life is possible after curative esophagectomy for carcinoma. J. Surg. Oncol. 2010;102:516–522. © 2009 Wiley‐Liss, Inc.
Multivariant optimization, validation, and application of capillary electrophoresis for simultaneous determination of polyphenols and phenolic acids in Brazilian wines
Authors: Peres Renato G. , Micke Gustavo A. , Tavares Marina F. M. , Rodriguez‐Amaya Delia B. 
Published: October 2009

AbstractA method for the simultaneous determination of the stilbene resveratrol, four phenolic acids (syringic, coumaric, caffeic, and gallic acids), and five flavonoids (catechin, rutin, kaempferol, myricetin, and quercetin) in wine by CE was developed and validated. The CE electrolyte composition and instrumental conditions were optimized using 27‐3 factorial design and response surface analysis, showing sodium tetraborate, MeOH, and their interaction as the most influential variables. The optimal electrophoretic conditions, minimizing the chromatographic resolution statistic values, consisted of 17 mmol/L sodium tetraborate with 20% methanol as electrolyte, constant voltage of 25 kV, hydrodynamic injection at 50 mbar for 3 s, and temperature of 25°C. The R2 values for linearity varied from 0.994 to 0.999; LOD and LOQ were 0.1 to 0.3 mg/L and 0.4 to 0.8 mg/L, respectively. The RSDs for migration time and peak area obtained from ten consecutive injections were less than 2% and recoveries varied from 97 to 102%. The method was applied to 23 samples of inexpensive Brazilian wines, showing wide compositional variation.
Characterization of the polyphenolic fraction of Morus alba leaves extracts by HPLC coupled to a hybrid IT‐TOF MS system
Authors: Dugo Paola , Donato Paola , Cacciola Francesco , Paola Germanò Maria , Rapisarda Antonio , Mondello Luigi 
Published: October 2009

AbstractInfusions or dried leaves from Morus alba (L., Moraceae) have long been used in folk medicine for the prevention or treatment of several diseases. Despite the great interest in determining the role of phytonutrients as potential therapeutic agents, and the rising demand of natural sources with nutraceutic benefits, the antioxidant content of many foodstuffs is unknown, making accurate estimation for human dietary consumption and the correlation to human diseases difficult. The high content in polyphenols mainly accounts for in vitro and in vivo antioxidant activity of extracts obtained from this plant, and it is responsible for their preventive and therapeutic roles in a number of human diseases. In this study, we achieved full characterization and quantitation of flavonoids and other phenolic components extracted from lyophilized mulberry leaves, by maceration with ethanol. To tackle such a task, an RPLC‐diode array detector‐MS system was optimized, employing a partially porous octadecylsilica column as stationary phase. Identification of mulberry leaves constituents was carried out on the basis of the complementary information obtained from their migration times, diode array spectra, MS ions, and MS/MS fragments. The employment of the hybrid (IT‐TOF) mass spectrometer further allowed the structural assignment of a series of structural isomers. To the best of our knowledge, 11 out of 22 identified compounds are being reported in mulberry leaves for the first time, and the relative amounts determined, in the two cultivars analyzed.
Chemometric extraction of analyte‐specific chromatograms in on‐line gradient LC‐infrared spectrometry
Authors: Kuligowski Julia , Quintás Guillermo , Garrigues Salvador , de la Guardia Miguel 
Published: October 2009

AbstractThis work exploits the possibilities offered by the recently developed multivariate method named Science‐Based Calibration (SBC), for the extraction of ‘analyte‐specific’ chromatograms in on‐line gradient reversed phase LC‐infrared spectrometry (IR) in the presence of a high spectral and chromatographic overlapping between the analyte of interest, co‐eluting sample matrix constituents and the mobile phase components. The SBC method uses an experimentally measured single response spectrum of the analyte of interest and representative noise to calculate an optimum regression vector (bopt(1)). Then, the bopt(1) vector is used to predict the concentration of the analyte of interest in the spectra of the LC‐IR sample chromatograms. To evaluate the advantages and pitfalls of the proposed approach, two different situations were analysed on real LC‐IR data sets obtained from the injection of a series of standard solutions of four nitrophenols (p‐nitrophenol, 3‐methyl‐4‐nitrophenol, 2,4‐dinitrophenol and 4‐nitrophenol) in a reversed phase system under gradient conditions. In the first situation, the extraction of the ‘analyte‐specific’ chromatogram was carried out without previous knowledge of the spectral features of other interferents present in the sample matrix. In a second situation evaluated, data obtained from the LC injection of a sample blank is available. Results show the potential applicability of this technique in a variety of situations and evidenced that the proposed chemometric approach improves the selectivity and sensitivity of the LC‐IR hyphenation.
Application of dispersive liquid–liquid microextraction for the determination of phenylurea herbicides in water samples by HPLC‐diode array detection
Authors: Saraji Mohammad , Tansazan Neda 
Published: October 2009

AbstractA simple dispersive liquid–liquid microextraction method combined with HPLC‐photodiode array detection has been developed for the determination of phenylurea herbicides in water samples. The herbicides studied included tebuthiuron, diuron, propanil, fluometuron, siduron, linuron, thidiazuron, and diflubenzuron. Several factors influencing the extraction efficiency of the studied compounds, such as extraction and disperser solvent type and their volumes, co‐solvent type and its fraction, and ionic strength were investigated and optimized. Under the optimum extraction conditions, the calibration graphs were linear in the range of 0.2–200 μg/L for target analytes. The enrichment factors were between 11 and 118. The LOD were in the range of 0.01–0.5 μg/L (S/N=3). The relative standard deviations obtained ranged from 3.0 to 7.8% (n=5).
Good for workers, good for companies: How knowledge sharing benefits individual employees
Authors: Reychav Iris , Weisberg Jacob 
Published: October 2009

AbstractThe paper aims to identify the ways in which explicit and tacit knowledge sharing occur in organizations and to investigate the impact of sharing these two knowledge types on the employee's rewards, performance, and intention to leave.This paper focuses on two hi‐tech companies working in the telecommunications field producing cellular networks. The final sample consisted of 278 completed questionnaires from business departments including finance, R&D, marketing, IT, engineering, and manufacturing.Explicit knowledge sharing is perceived by the employees as having: (1) a direct positive effect on the receipt of monetary rewards; (2) a positive indirect effect on the employee's performance; and it has a (3) positive direct and negative indirect effects on employee's intention to leave. Tacit knowledge sharing is perceived by employees as having: (1) a positive direct effect on the receipt of non‐monetary rewards; (2) a positive direct effect on performance; and (3) it has a positive indirect effect on employee's intention to leave.Although the findings show that increased knowledge sharing results in positive outcomes at the individual level, the research model would benefit from an examination of larger samples for reasons of statistical complexity analysis and in order to allow for generalizability of the results to other companies that operate in similar environments. It would also be worthwhile to conduct a comparative analysis of companies from different industries.Understanding knowledge‐sharing behaviors may prove helpful to managers in developing strategies to encourage organizational knowledge sharing and in the development of an organizational knowledge base. The knowledge sharing outcomes outlined here can give employees a way to predict potential positive outcomes and benefits that are likely to arise as a result of engaging in knowledge sharing activities.The model enables for the first time to substantiate, in a valid way, to hypothesize that knowledge sharing within an organization is perceived by employees to be a rewarding behavior, improving employees' performance, and decrease the intention to leave. Copyright © 2009 John Wiley & Sons, Ltd.