bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pex3p‐dependent peroxisomal biogenesis initiates in the endoplasmic reticulum of human fibroblasts
Authors: Toro Andrés A. , Araya Claudia A. , Córdova Gonzalo J. , Arredondo Cristian A. , Cárdenas Hugo G. , Moreno Regina E. , Venegas Alejandro , Koenig Cecilia S. , Cancino Jorge , Gonzalez Alfonso , Santos Manuel J. 
Published: May 2009

AbstractThe mechanisms of peroxisomal biogenesis remain incompletely understood, specially regarding the role of the endoplasmic reticulum (ER) in human cells, where genetic disorders of peroxisome biogenesis lead to Zellweger syndrome (ZS). The Pex3p peroxisomal membrane protein (PMP) required for early steps of peroxisome biogenesis has been detected in the ER in yeast but not in mammalian cells. Here, we show that Pex3p‐GFP expressed in a new ZS cell line (MR), which lacks peroxisomes due to a mutation in the PEX3 gene, localizes first in the ER and subsequently in newly formed peroxisomes. Pex3p bearing an artificial N‐glycosylation site shows an electrophoretic shift indicative of ER targeting while en route to preformed peroxisomes in normal fibroblast. A signal peptide that forces its entry into the ER does not eliminate its capability to drive peroxisome biogenesis in ZS cells. Thus, Pex3p is able to drive peroxisome biogenesis from the ER and its ER pathway is not privative of ZS cells. Cross‐expression experiments of Pex3p in GM623 cells lacking Pex16p or Pex16p in MR cells lacking Pex3p, showed evidence that Pex3p requires Pex16p for ER location but is dispensable for the ER location of Pex16p. These results indicate that Pex3p follows the ER‐to‐peroxisomal route in mammalian cells and provides new clues to understand its function. J. Cell. Biochem. 107: 1083–1096, 2009. © 2009 Wiley‐Liss, Inc.
Neural crest‐derived stem cells display a wide variety of characteristics
Authors: Nagoshi Narihito , Shibata Shinsuke , Nakamura Masaya , Matsuzaki Yumi , Toyama Yoshiaki , Okano Hideyuki 
Published: May 2009

AbstractA recent burst of findings has shown that neural crest‐derived stem cells (NCSCs) can be found in diverse mammalian tissues. In addition to their identification in tissues that are known to be derived from the neural crest, recent studies have revealed NCSCs in tissues that are not specifically derived from the neural crest, such as bone marrow. NCSCs can express a wide range of characteristics, and which properties are expressed mainly depends on their tissue sources and the ontogenic stage of the animal. The identification of NCSCs in various tissues opens an entirely new avenue of approach to developing autologous cell replacement therapies for use in regenerative medicine. In this review, we discuss the origin, migration, and lineage potential of NCSCs from various mammalian tissue sources. J. Cell. Biochem. 107: 1046–1052, 2009. © 2009 Wiley‐Liss, Inc.
Force field dependence of phospholipid headgroup and acyl chain properties: Comparative molecular dynamics simulations of DMPC bilayers
Authors: Prakash Priyanka , Sankararamakrishnan Ramasubbu 
Published: May 2009

AbstractThe reliability of molecular simulations largely depends on the quality of the empirical force field parameters. Force fields used in lipid simulations continue to be improved to enhance the agreement with experiments for a number of different properties. In this work, we have carried out molecular dynamics simulations of neat DMPC bilayers using united‐atom Berger force field and three versions of all‐atom CHARMM force fields. Three different systems consisting of 48, 72, and 96 lipids were studied. Both particle mesh Ewald (PME) and spherical cut‐off schemes were used to evaluate the long‐range electrostatic interactions. In total, 21 simulations were carried out and analyzed to find out the dependence of lipid properties on force fields, system size, and schemes to calculate long‐range interactions. The acyl chain order parameters calculated from Berger and the recent versions of CHARMM simulations have shown generally good agreement with the experimental results. However, both sets of force fields deviate significantly from the experimentally observed P‐C dipolar coupling values for the carbon atoms that link the choline and glycerol groups with the phosphate groups. Significant differences are also observed in several headgroup parameters between CHARMM and Berger simulations. Our results demonstrate that when changes were introduced to improve CHARMM force field using PME scheme, all the headgroup parameters have not been reoptimized. The headgroup properties are likely to play a significant role in lipid–lipid, protein–lipid, and ligand–lipid interactions and hence headgroup parameters in phospholipids require refinement for both Berger and CHARMM force fields. © 2009 Wiley Periodicals, Inc.J Comput Chem, 2010
SMILES‐based optimal descriptors: QSAR analysis of fullerene‐based HIV‐1 PR inhibitors by means of balance of correlations
Authors: Toropov Andrey A. , Toropova Alla P. , Benfenati Emilio , Leszczynska Danuta , Leszczynski Jerzy 
Published: May 2009

AbstractQuantitative structure‐activity relationships (QSAR) for prediction of binding affinities (pEC50, i.e., minus decimal logarithm of the 50% effective concentration) of 20 fullerene derivatives inhibitors of the HIV‐1 PR (human immunodeficiency virus type 1 protease) have been developed by application of the optimal descriptors approach calculated with SMILES (simplified molecular input line entry system). The applied models were constructed by the balance of correlations. Three various splits of the experimental data into subtraining set, calibration set, and test set were examined. Comparison of classic scheme (training‐test system) and the balance of correlations (subtraining‐calibration‐test system) show that the balance of correlations gives more robust predictions than the classic scheme for the pEC50 of the fullerene derivatives. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010
Effect of microbial treatment on brightness and heat‐induced brightness reversion of high‐yield pulps
Authors: Tang Wenzhu , Li Xuezhi , Zhao Jian , Yue Jun , Yue Hua , Qu Yinbo 
Published: May 2009

AbstractBACKGROUND: The manufacture of high‐yield pulps is attractive due to its efficient utilization of lignocellulosic material. However, their rapid brightness reversion when exposed to heat and light restricts their more widespread use in high‐quality papers. This study investigated the potential of bio‐treatment with more than 30 species of fungi and yeasts to inhibit heat‐induced yellowing of high‐yield pulps.RESULTS: Treatment with Penicillium sp. ZCF34, Saccharomyces cerevisiae INVS2 and 724 reduced the brightness reversion and increased the brightness of wheat straw semi‐chemical pulp after 4 days incubation (postcolor number decreased by 33.96%, 66.42% and 57.09%, and brightness increased by 0.84%ISO, 0.48%ISO and 0.89%ISO, respectively). Phanerochaete chrysosporium W14 treatment was best for depressing yellowing of bleached aspen CTMP (chemi‐thermo‐mechanical pulp) and Saccharomyces cerevisiae AH22 treatment gave the highest brightness and a lower postcolor number. For unbleached aspen CTMP, treatment with Fusarium concolor X4 and Saccharomyces cerevisiae H158 was effective in improving brightness and brightness stability after 2 and 4 days incubation, respectively.CONCLUSION: Treatment with some microorganisms increased pulp brightness and strongly suppressed heat‐induced yellowing. It offers an option for improving the brightness stability of high yield pulps and some valuable information for bio‐pulping and bio‐bleaching with microbial treatment. Copyright © 2009 Society of Chemical Industry
Fate of horseradish peroxidase during oxidation of monobrominated phenols
Authors: Cohen‐Yaniv Vered , Dosoretz Carlos G. 
Published: May 2009

AbstractBACKGROUND: Peroxidase‐catalyzed polymerization of phenols is accompanied by substantial enzyme precipitation with reaction products. The enzyme fate during the polymerization of monobromophenols by horseradish peroxidase (HRP) was studied. Enzyme fate was simultaneously monitored by protein, total nitrogen mass balance and gel electrophoresis (SDS‐PAGE) analysis of both soluble and precipitate fractions.RESULTS: SDS‐PAGE analysis revealed that molecular weight bands of protein in the precipitate shifted upwards toward higher molecular weights, compared with protein control. When co‐polymerization was practiced higher HRP precipitation occurred compared with polymerization of a single substrate, regardless of substrate combination applied. Addition of polyethylene glycol (PEG) to the reaction mixture decreased the extent of HRP precipitation. At 2 mmol L−1 H2O2, corresponding to the stoichiometric equivalent concentration, 50% precipitation occurred after 1 h (∼70% after 24 h) compared with 97–98% (∼100% after 24 h) without PEG. Nevertheless, further increase of H2O2 increased HRP precipitation regardless of PEG (85% at 4 mmol L−1 and 95% at 5 mmol L−1). The lowest degree of enzyme inactivation was observed for metabromophenol, which displayed the lowest transformation yield, compared to the other congeners.CONCLUSIONS: Results from SDS‐PAGE indicate that an interaction stronger than hydrophobic, resisting the denaturative conditions, may take place between HRP and the reaction products, suggesting the occurrence of a covalent link between them. Oxidation was enhanced by inclusion of PEG, which partially suppressed product‐dependent inactivation. The extent of enzyme inactivation depends on the substrate used, while highest inactivation occurred when co‐polymerization was practiced. Copyright © 2009 Society of Chemical Industry
Regioselective synthesis of bioactive spiro heterocyclic compounds containing both indoline and quinolone moieties by aryl radical cyclization
Authors: Majumdar K. C. , Kundu N. 
Published: May 2009

Abstract
magnified imageThe tin hydride‐mediated aryl radical cyclization of a number of 4‐(2′‐bromo‐N‐methylanilino)methyl‐1‐alkylquinolin‐2(1H)‐ones under mild neutral condition afforded 1‐alkyl‐3,4‐dihydroquinolin‐2(1H)‐one‐4‐spiro‐3′‐(1‐methylindolines) in excellent yield. The starting materials, amines were derived from 4‐bromomethyl‐N‐methyl quinolin‐2(1H)‐ones and 2‐bromo‐N‐methyl anilines by refluxing in acetone in the presence of anhydrous potassium carbonate and sodium iodide (Finkelstein condition). J. Heterocyclic Chem., 46, 492 (2009).
An efficient synthesis of indeno[1,2‐b]pyridine and benzo[h]quinoline derivatives under solvent‐free conditions
Authors: Rong Liangce , Han Hongxia , Jiang Hong , Tu Shujiang 
Published: May 2009

Abstract
magnified imageAn efficient and convenient multicomponent reaction for the preparation of 4‐aryl‐2‐oxo‐2,5‐dihydro‐1H‐indeno[1,2‐b]pyridine‐3‐carbonitrile and 4‐aryl‐2‐oxo‐1,2,5,6‐tetrahydrobenzo[h]quinoline‐3‐carbonitrile derivatives by the 2,3‐dihydroinden‐1‐one or 3,4‐dihydronaphthalen‐1(2H)‐one, aromatic aldehydes, and malononitrile in the presence of sodium hydroxide under solvent‐free condition is reported. The short reaction time coupled with the simplicity of the reaction procedure makes this method one of the most efficient methods for the synthesis of these classes of compounds. J. Heterocyclic Chem., 46, 465 (2009).
Ring‐expansion of 5‐methylene‐thiazolidine‐2‐thione with hydrazine
Authors: Safarov Saifidin , Pulatov Elmurod , Kukaniev Muhamacho Amadovich , Kolshorn Heinz , Meier Herbert 
Published: May 2009

Abstract
magnified imageThe treatment of 5‐methylene‐thiazolidine‐2‐thione with hydrazine hydrate in boiling dioxane leads in a novel type of ring‐expansion reaction to 6‐methyl‐1,2,4‐triazine‐3‐thione. J. Heterocyclic Chem., 46, 552 (2009).
Synthesis and properties of diaza‐, triaza‐, and tetraazaphenothiazines
Authors: Pluta Krystian , Morak‐Młodawska Beata , Jeleń Małgorzata 
Published: May 2009

Abstractmagnified imageThe review surveys the chemistry of diaza‐, triaza‐, and tetraazaphenothiazines and their benzo and dibenzo derivatives consisting of over 30 different heterocyclic systems. J. Heterocyclic Chem., 46, 355 (2009).
Suzuki–Miyaura arylations of tetramic acid sulfonates: Evaluation of lactam protection, sulfonate esters, and sterics
Authors: Yoon‐Miller Sarah J. P. , Dorward Kathryn M. , White Kimberly P. , Pelkey Erin T. 
Published: May 2009

Abstract
magnified imageThe synthesis of 3,4‐diaryl‐3‐pyrrolin‐2‐ones and 4‐aryl‐3‐pyrrolin‐2‐ones using Suzuki–Miyaura cross‐coupling reactions of tetramic acid sulfonates with arylboronic acids has been studied. The effect that sulfonate ester, sterics, and lactam protection has on the cross‐coupling reaction was evaluated. As expected, triflates were better cross‐coupling partners than the corresponding tosylates. The yields were only partially affected by the incorporation of aryl groups at the 3‐position. Importantly, tetramic acid triflates (and to a lesser extent tosylates) lacking a lactam protecting group were still competent substrates. J. Heterocyclic Chem., 46, 447 (2009).
Expanding leadership diversity through formal mentoring programs
Authors: Olson Deborah A. , Jackson Deborrah 
Published: May 2009

AbstractTo attract and retain people, it is essential that organizations design and successfully implement programs and processes that develop people and nurture their talents. For those who aspire to a leadership role, the opportunity to engage in mentoring relationships with senior‐level leaders is a powerful way to accelerate growth. In the majority of informal mentoring relationships, mentors and protégés share similar racial, gender, and cultural backgrounds. Senior leaders in most large organizations are still primarily white males. As a result, it can be difficult for people from diverse backgrounds who aspire to higher level leadership roles to find senior executives with whom they can develop a mentoring relationship. To address this challenge, some organizations have implemented formal mentoring programs that are specifically designed to facilitate development of people from diverse backgrounds. Unfortunately, previous research studies conducted on the impact of formal mentoring relationships have shown that these programs do not consistently achieve the desired outcomes. The change intervention described in this article suggests that formal mentoring programs can significantly influence the movement of protégés from diverse backgrounds into higher level leadership positions.
Practicing talent life cycle management
Authors: Kirwan Karen S. 
Published: May 2009

AbstractAs far back as the ninth century BCE in Greece, a talent was a form of currency. In the 21st century, talents remain currency as the special gifts of knowledge, skills, and personal characteristics that individuals bring to organizations. Talent management, also known as human capital management, HCM, is a focus of leadership studies that increasingly strives to acknowledge and measure the tangible contributions that individuals make to the bottom line. In this symposium, we offer a position paper by Ted Harro and Leslie Miller who detail an innovative approach to address how leaders of organizations can create a consistent, positive flow of talent necessary to support success. Our respondents, Karen Kirwan, Dave Wondra, and Edward Perez, each add their perspectives to this timely discussion.
Analyzing single‐molecule manipulation experiments
Authors: Calderon Christopher P. , Harris Nolan C. , Kiang Ching‐Hwa , Cox Dennis D. 
Published: May 2009

AbstractSingle‐molecule manipulation studies can provide quantitative information about the physical properties of complex biological molecules without ensemble artifacts obscuring the measurements. We demonstrate computational techniques which aim at more fully utilizing the wealth of information contained in noisy experimental time series. The “noise” comes from multiple sources e.g., inherent thermal motion, instrument measurement error, etc. The primary focus of this paper is a methodology that uses time domain based methods to extract the effective molecular friction from single‐molecule pulling data. We studied molecules composed of eight tandem repeat titin I27 domains, but the modeling approaches have applicability to other single‐molecule mechanical studies. The merits and challenges associated with applying such a computational approach to existing single‐molecule manipulation data are also discussed. Copyright © 2009 John Wiley & Sons, Ltd.
Two decades of hepatitis B infections among drug users in Amsterdam: Are they still a high‐risk group?
Authors: van Houdt Robin , van den Berg Charlotte H.S.B. , Stolte Ineke G. , Bruisten Sylvia M. , Dukers Nicole H.T.M. , Bakker Margreet , Wolthers Katja C. , Prins Maria , Coutinho Roel A. 
Published: May 2009

AbstractIn general, little is known about the incidence of hepatitis B virus (HBV) among drug users, especially among non‐injecting drug users. Therefore, changes in incidence, risk factors, and circulating genotypes over time were determined among drug users in Amsterdam over an 18‐year period (1985–2002). Sera of 1,268 drug users, both injecting and non‐injecting, were screened for anti‐HBc. HBV genotypes of the anti‐HBc seroconverters were determined. Poisson regression was used to test for temporal trends in incidence and to identify risk factors for seroconversion. Of the 598 participants who were anti‐HBc negative at entry, 83 seroconverted for anti‐HBc. The incidence of HBV declined from 5.9/100 Person Years up to 1993 to 0/100 Person Years in 2002. Of the drug users infected acutely, both injecting and non‐injecting, 88% were infected with the same genotype D, serotype ayw3 strain. Multivariate analyses revealed current injecting, age, and calendar year of visit as independent risk factors. The decline in the incidence of HBV among drug users in Amsterdam is probably caused by a decline in injecting behavior. Injecting and non‐injecting drug users were infected with the same strain, indicating that drug users infect one another, regardless of their risk behavior. After 2000, no injecting drug users with an acute HBV infection were reported to the Public Health Service Amsterdam and the specific genotype D strain had disappeared. These findings suggest that drug users may no longer be a high‐risk group for HBV infection in Amsterdam. However, trends in drug use need to be monitored. J. Med. Virol. 81:1163–1169, 2009. © 2009 Wiley‐Liss, Inc.
Evidence that methylation of hepatitis B virus covalently closed circular DNA in liver tissues of patients with chronic hepatitis B modulates HBV replication
Authors: Guo Yanhai , Li Yongnian , Mu Shijie , Zhang Ju , Yan Zhen 
Published: May 2009

AbstractEpigenetic factors may modulate chronic Hepatitis B viral infection by affecting virion gene transcription. The aim of this study was to compare the methylation status of the intrahepatic covalently closed circular DNA (cccDNA) CpG island 2 and HBV replication capability. HBV cccDNA was extracted from liver biopsies of 55 HBsAg‐positive patients with chronic hepatitis B (32 HBeAg‐positive and 23 HBeAg‐negative), and was analyzed for methylation status and quantity. The two Hpa II recognition sequences CCpGG in the CpG island 2 were methylated in infected liver tissues from 24 (43.6%) of 55 patients. Positive ratios of cccDNA methylation were significantly higher in HBeAg‐negative patients (15/23, 65.2%) than HBeAg‐positive patients (9/32, 28.1%) (P < 0.05). The percentage of methylated‐cccDNA/total‐cccDNA of HBeAg‐negative samples (a median of 48%, ranging from 5% to 83%) was significantly higher (P < 0.001) than HBeAg‐positive samples (a median of 14%, ranging from 0.26% to 35%). Ratios of relaxed circular DNA (rcDNA) to cccDNA molecules revealed that cccDNA methylation correlated with impaired virion productivity in HBeAg‐positive individuals (P < 0.05). The bisulfite DNA sequencing showed that methylation density was significantly higher in HBeAg‐negative than in HBeAg‐positive patients (P < 0.05). The methylation level of the CpG island 2 of the cccDNA in HBeAg‐negative patients was higher than that in HBeAg‐positive patients, suggesting that HBV cccDNA methylation may be relevant to replication capability of HBV. J. Med. Virol. 81:1177–1183, 2009. © 2009 Wiley‐Liss, Inc.
Characterization of cytotoxic T‐lymphocyte epitopes and immune responses to SARS coronavirus spike DNA vaccine expressing the RGD‐integrin‐binding motif
Authors: Poh W.P. , Narasaraju T. , Pereira N.A. , Zhong F. , Phoon M.C. , Macary P.A. , Wong S.H. , Lu J. , Koh D.R. , Chow Vincent T.K. 
Published: May 2009

AbstractIntegrins are critical for initiating T‐cell activation events. The integrin‐binding motif Arg‐Gly‐Asp (RGD) was incorporated into the pcDNA 3.1 mammalian expression vector expressing the codon‐optimized extracellular domain of SARS coronavirus (SARS‐CoV) spike protein, and tested by immunizing C57BL/6 mice. Significant cell‐mediated immune responses were characterized by cytotoxic T‐lymphocyte 51Cr release assay and interferon‐gamma secretion ELISPOT assay against RMA‐S target cells presenting predicted MHC class I H2‐Kb epitopes, including those spanning residues 884–891 and 1116–1123 within the S2 subunit of SARS‐CoV spike protein. DNA vaccines incorporating the Spike‐RGD/His motif or the Spike‐His construct generated robust cell‐mediated immune responses. Moreover, the Spike‐His DNA vaccine construct generated a significant antibody response. Immunization with these DNA vaccine constructs elicited significant cellular and humoral immune responses. Additional T‐cell epitopes within the SARS‐CoV spike protein that may contribute to cell‐mediated immunity in vivo were also identified. J. Med. Virol. 81:1131–1139, 2009. © 2009 Wiley‐Liss, Inc.
Neuronal expression of the proteolipid protein gene in the medulla of the mouse
Authors: Miller Martha J. , Kangas Cindy D. , Macklin Wendy B. 
Published: May 2009

AbstractThe proteolipid protein (PLP) gene (Plp) encodes the major myelin proteins, PLP and DM20. Expression of Plp occurs predominantly in oligodendrocytes, but evidence is accumulating that this gene is also expressed in neurons. In earlier studies, we demonstrated that myelin‐deficient (MD) rats, which carry a mutation in the Plp gene, exhibit lethal hypoxic ventilatory depression. Furthermore, we found that, in the MD rat, PLP accumulated in neuronal cell bodies in the medulla oblongata. In the current study, we sought to determine which neurons expressed the Plp gene in the medulla oblongata and whether Plp gene expression changed in neurons with maturation. A transgenic mouse expressing the Plp promoter driving expression of enhanced green fluorescent protein (Plp‐EGFP) was used to identify neurons expressing this gene. Plp expression in neurons was confirmed by immunostaining EGFP‐positive cells for NeuN and by in situ hybridization for PLP mRNA. The numbers of neurons expressing Plp‐EGFP and their distribution increased between P5 and P10 in the medulla. Immunostaining for surface receptors and classes of neurons expressing Plp‐EGFP revealed that Plp gene expression in brainstem neurons was restricted to neurons expressing specific ligand‐gated channels and biosynthetic enzymes, including glutamatergic NMDA receptors, GABAA receptors, and ChAT in defined areas of the medulla. Plp gene expression was rarely found in interneurons expressing GABA and was never found in AMPA receptor‐ or tyrosine hydroxylase‐expressing neurons. Thus, Plp expression in the mouse caudal medulla was found to be developmentally regulated and restricted to specific groups of neurons. © 2009 Wiley‐Liss, Inc.