bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of absolute configuration—An overview related to this Special Issue
Authors: Allenmark Stig , Gawronski Jacek 
Published: January 2008

AbstractRapid progress in asymmetric synthesis stimulated a further development of methods and techniques for the determination of absolute configuration of chiral molecules. In recent years the direct methods, i.e. X‐ray diffraction analysis, circular dichroism (vibrational and electronic), Raman optical activity, optical rotation measurements, as well as indirect methods for relative configuration assignment with the use of NMR spectroscopy or enzymatic transformations, are receiving increasing attention not only by specialists in the field but also by synthetic and structural chemists alike. This paper provides a short overview of the methods currently used, as well as references to contributions collected in this Thematic Issue of Chirality. Chirality, 2008. © 2008 Wiley‐Liss, Inc.
Single diastereomers of unsymmetrical tris‐spirocyclic cyclotriphosphazenes based on 1,1′‐bi‐2‐naphthol—Synthesis and structures
Authors: Bhuvan Kumar N. N. , Kumara Swamy K. C. 
Published: January 2008

AbstractDiastereoselective synthesis and characterization of chiral unsymmetrical tris‐spirocyclic cyclotriphosphazenes based on chiral 1,1′‐bi‐2‐naphthol (BINOL) are reported. Specifically, the chiral compounds (−)N3P3[1,1′‐O2(C10H6)2](O‐2,2′C6H4‐C6H4O)Cl2 [(−)‐4] and (−)N3P3[1,1′‐O2(C10H6)2](OCH2CH2NMe)2 [(−)‐5] are prepared by starting with the chiral mono‐spiro compound (−)N3P3[1,1′‐O2(C10H6)2]Cl4 [(−)‐3]. Synthesis of four other chiral spirocyclics, N3P3[1,1′‐O2(C10H6)2](OCH2CH2 NMe)(O‐2,2′C6H4‐C6H4O)[(−)‐6 and (+)‐6], N3P3[1,1′‐O2(C10H6)2](NMe2)4 [(−)‐7], N3P3[1,1′‐O2(C10H6)2](O‐2,2′C6H4‐C6H4O)(NMeCH2CH2OH)2 [(−)‐8 and (+)‐8], and N3P3[1,1′‐O2(C10H6)2](O‐2,2′C6H4‐C6H4O)[NHCH2CH2CH2Si(OEt)3]2 (9) is also reported herein. Compounds 4–6 are obtained in the solid state diastereoselectively and their X‐ray structures have been determined and discussed. The diastereoselectivity is also shown by structural characterization of two distinct isomers in the case of 6 [(−)‐6 and (+)‐6, respectively] by starting with precursor of 3 having (R) or (S)‐BINOL residue. The 1H NMR spectra of 7 and 8 exhibit doublets with virtual coupling for the methyl protons, consistent with the chiral nature of the binaphthoxy residue. The potential of 9, which hydrolyzes readily in CDCl3 solution, as a useful precursor for chiral polymer applications is highlighted. Chirality, 2008. © 2008 Wiley‐Liss, Inc.
Equity recognition of mandatory accounting changes: the case of transitional goodwill impairment losses
Authors: Lapointe‐Antunes Pascale , Cormier Denis , Magnan Michel 
Published: January 2008

AbstractThis study investigates if and how the use of the retroactive method to account for a mandatory accounting change affects a firm's measurement and recognition choices. We examine if reporting incentives and constraints are associated with the magnitude of transitional goodwill impairment losses reported by Canadian firms implementing Section 3062 on purchased goodwill. Our results indicate firms have an incentive to both overstate and understate transitional goodwill impairment losses. We also show that financially literate and independent audit committees constrain managerial opportunism. Copyright © 2008 ASAC. Published by John Wiley & Sons, Ltd.
Transcatheter Closure of Large Atrial Septal Defects in 18 Patients
Authors: Guan Zhanjun , Qin Yongwen , Zhao Xianxian , Ding Jijun , Zheng Xing , Nguyen Vince 
Published: January 2008

AbstractPurposeThis study was designed to evaluate the efficacy and safety of transcatheter closure of large atrial septal defects (ASD).MethodsEighteen patients diagnosed as ostium secundum defect with a diameter of 30‐40 mm were enrolled in this study. With the guidance of echocardiography and fluoroscopy, the Amplazter occlusion devices were implanted percutaneously through the femoral vein.ResultsA small residual left‐to‐right shunt was detected with echocardiography immediately postprocedure but resolved after 1 week. The occlusion devices remained in proper position, and there was no residual shunt at 1‐ and 29‐month follow‐ups. Cardiac function and atrial sizes improved significantly as compared with the preclosure states.ConclusionsTranscatheter closure of large atrial septal defects with the Amplazter occlusion device is feasible, safe and effective. Copyright © 2008 Wiley Periodicals, Inc.
In Search of the False‐negative Exercise Treadmill Testing Evidence‐based Use of Exercise Echocardiography
Authors: Southard Jeffrey , Baker Larry , Schaefer Saul 
Published: January 2008

AbstractBackgroundControversy exists regarding the role of exercise treadmill testing (ETT) versus exercise stress echocardiography (ESE) as the appropriate initial noninvasive test to risk‐stratify patients with chest pain. The majority of studies to date that evaluated these methodologies included patients with poor functional status and baseline electrocardiogram (ECG) abnormalities, potentially limiting the sensitivity of ETT.HypothesisWe examined the hypothesis that given stringent standards of exercise duration and ECG interpretability, the ETT would have a high diagnostic sensitivity for the presence of significant coronary artery disease (CAD).MethodsResults of concurrent ETT and ESE in 3,098 patients were examined, and the subset of patients with a negative ETT and positive ESE (−ETT/ + ESE) were reviewed for the presence of CAD as a function of exercise duration (< or ≥ 6 min) and baseline ECG normality.ResultsIn those patients with a − ETT/ + ESE who exercised ≥ 6 min, 54 had a normal baseline ECG, 22 underwent angiography and 6 had CAD (all of whom had either small, grafted or collateralized vessels). Patients with a − ETT/ + ESE who were incapable of exercising 6 min were more frequently older and female. Mortality was significantly greater in the < 6 min exercise duration group (31.4 versus 3.1%).ConclusionsThese findings support the use of the ETT without imaging as the initial test in patients with chest pain who have a normal baseline ECG and are able to exercise 6 min. Using these criteria, false negative findings are generally seen in patients without critical large vessel epicardial disease. The ESE should be reserved as the initial test for patients with an abnormal baseline ECG or reduced functional capacity. Copyright © 2008 Wiley Periodicals, Inc.
Factors Associated with Non‐adherence to Therapy with Warfarin in a Population of Chronic Heart Failure Patients
Authors: Pamboukian Salpy V. , Nisar Imran , Patel Sheetal , Gu Liping , McLeod Mary , Costanzo Maria Rosa , Heroux Alain 
Published: January 2008

AbstractBackgroundAdherence to heart failure therapy is important in reducing morbidity and mortality over the course of the disease process. The aim of this study was to examine factors associated with non‐adherence to warfarin in chronic heart failure patients.MethodsEighty patients receiving warfarin therapy in 2002 were included. Adherence was defined as maintenance of international normalized ratio (INR) between 2 and 3.5 and keeping scheduled appointments for INR checks at least 75% of the time. Clinical variables examined included age, gender, race, insurance, left ventricular ejection fraction (LVEF), etiology, New York heart association (NYHA) class, comorbidities, smoking, and alcohol use.ResultsOf 80 patients studied, 59 were male with mean age ( ± standard deviation) 52 ± 13 years, 24 had ischemic etiology with mean LVEF of 24% ± 9%. Non‐adherence was associated with tobacco use, odds ratio of 6.5 (p <0.01). Ischemic etiology was associated with adherence, odds ratio of 4.5 (p <0.01). Non‐adherent patients were more likely to be insured with Medicare/Medicaid (p = 0.04) and have better NYHA class (p = 0.04). Adherence positively correlated with older age and lower LVEF, and negatively correlated with number of hospitalizations (p<0.01 for all). In a multiple regression model, patients with improvement in LVEF had decreased adherence over the year (p<0.01).ConclusionsThe profile of heart failure patients who demonstrated non‐adherence to warfarin therapy included younger age, nonischemic etiology, better NYHA class, smoking, insurance with Medicare/Medicaid and improved LVEF over the study. Measures targeting these patients may result in improved adherence to other pharmacologic treatments of heart failure. Copyright © 2008 Wiley Periodicals, Inc.
Imaging of Coronary Artery Fistulas by Multidetector Computed Tomography: Is Multidetector Computed Tomography Sensitive?
Authors: Kacmaz Fehmi , Isiksalan Ozbulbul Nilgun , Alyan Omer , Maden Orhan , Demir Ahmet Duran , Atak Ramazan , Senen Kubilay , Erbay Ali Riza , Balbay Yucel , Olcer Tulay , Ilkay Erdogan 
Published: January 2008

AbstractBackgroundCoronary angiography is the gold standard for diagnosing coronary artery fistulas (CAFs). Multidetector computed tomography (MDCT) is a recently developed imaging technique for detecting coronary artery stenosis, coronary artery anomalies, and coronary artery fistulas and their courses.ObjectiveWe aimed to determine accuracy or sensitivity of MDCT in patients having CAF.MethodWe evaluated 13 patients with 15 CAFs detected earlier by coronary angiography. MDCT was carried out on all patients and the results were compared with coronary angiography, following which, sensitivity of MDCT was detected.ResultsEleven of 15 CAFs were shown on MDCT and the overall sensitivity of MDCT was found to be 73%. Seven of 8 CAFs that coursed between two vascular structures were detected and the sensitivity of MDCT in this group was found to be 87%. However, the sensitivity of 58% of MDCT in patients with fistula coursing between coronary arteries and cardiac chambers was found.ConclusionAlthough coronary angiography is the gold standard diagnostic test for detection of CAF, MDCT may be an alternative test, especially, for CAF coursing between vascular structures, to detect origin, course, and the drainage site of fistula through its excellent spatial resolution and ability to show relationship of anatomic structures. Copyright © 2008 Wiley Periodicals, Inc.
Calcitonin receptor‐like receptor (CLR), receptor activity‐modifying protein 1 (RAMP1), and calcitonin gene‐related peptide (CGRP) immunoreactivity in the rat trigeminovascular system: Differences between peripheral and central CGRP receptor distribution
Authors: Lennerz Jochen K. , Rühle Victor , Ceppa Eugene P. , Neuhuber Winfried L. , Bunnett Nigel W. , Grady Eileen F. , Messlinger Karl 
Published: January 2008

AbstractCGRP meets its receptor in the rat dura mater. The CGRP receptor protein CLR (green) is expressed in smooth muscle cells (blue, SMA) in the media of meningeal arteries (left) but not in veins (right upper half). CLR is also found in trigeminal nerve bundles and mononuclear cells adjacent to the arteries. CGRP‐receptor components are however not colocalized with axonal CGRP (red) in the dura, but expressed in Schwann cells (not visible at this magnification). J. Comp. Neurol. 507:1277‐1299, 2008. © 2008 Wiley‐Liss, Inc.
Long‐term stabilized blood samples as controls for flow cytometric HLA‐B27 screening: A feasibility study
Authors: Levering Wilfried H. B. M. , Wind Henk , Granger Vivian , Sintnicolaas Kees , Hooijkaas Herbert , Reilly John T. , Gratama Jan W. , Barnett David 
Published: January 2008

AbstractBackground:Long‐term stabilized blood samples are potentially useful as positive or negative procedure controls for flow cytometric HLA‐B27 screening, and could serve as test samples in an external quality assessment (EQA) scheme. We evaluated long‐term stabilized whole blood specimens as prepared for the UK NEQAS for Leucocyte Immunophenotyping EQA scheme (Sheffield, UK).Methods:Peripheral blood samples were obtained from nine blood bank donors with known HLA‐B typing. Short‐term stabilization with Trans‐FIX™ was performed before shipment to Sheffield. Thereafter, long‐term stabilization was performed. Commercially available HLA‐B27 mAb were tested periodically between 1 week and 12 months on (i) fresh, (ii) short‐term stabilized, and (iii) long‐term stabilized blood samples using a stain, lyse, and wash technique. We compared the forward scatter (FSC), sideward scatter (SSC), and fluorescence signals of lymphocytes as a function of time. Furthermore, a pilot send‐out with stabilized blood samples of four blood bank donors was distributed among the participants to the Benelux EQA scheme for HLA‐B27 screening, and results were compared with historical EQA data obtained using nonstabilized blood samples from the same donors.Results:There were no major effects on FSC and SSC characteristics of lymphocytes. Background fluorescence of stabilized samples increased and specific fluorescence of stabilized HLA‐B27 positive samples decreased as compared with fresh samples. However, discrimination between the investigated HLA‐B27 positive and HLA‐B27 negative samples remained feasible poststabilization. In the pilot send‐out, the results obtained with stabilized samples were less concordant than with the corresponding fresh samples due to variable quality of the stabilized samples.Conclusion:Long‐term stabilized whole blood samples are potentially useful as true HLA‐B27 positive and true HLA‐B27 negative control cells for daily and longitudinal quality control of flow cytometric HLA‐B27 screening. In the same way, long‐term stabilized samples may be used for EQA purposes. However, these samples are currently not feasible for reagent validation purposes. Extensive quality control of long‐term stabilized samples is necessary before distribution in multicenter surveys. © 2008 Clinical Cytometry Society
A new case of acquired Glanzmann's thrombasthenia: Diagnostic value of flow cytometry
Authors: Giannini S. , Mezzasoma A. M. , Guglielmini G. , Rossi R. , Falcinelli E. , Gresele P. 
Published: January 2008

AbstractBackground:Acquired Glanzmann's thrombasthenia (aGT) is a rare hemorrhagic disorder caused by autoantibodies, alloantibodies, or paraproteins directed against platelet GPIIb/IIIa. Its diagnosis requires several laboratory assays and mixing tests, which are complex and time consuming. We describe here a new case of aGT and compare different tests for the detection of GPIIb/IIIa‐blocking autoantibodies.Methods:A previously healthy 27‐year‐old male developed severe mucocutaneous bleeding, despite a normal platelet count, associated with non Hodgkin lymphoma.Results:Blood clotting tests were normal. Bleeding time and PFA‐100® were unmeasurable. Platelet aggregation was absent in response to all agonists except ristocetin. Platelet adhesion to collagen at high shear was impaired. Platelet granular content and release was normal. Flow cytometry showed normal binding of some anti‐GPIIb/IIIa antibodies (SZ21 and SAP), and decreased binding of others (P2, SZ22, A2A 9/6). Binding of PAC‐1, against activated GPIIb/IIIa, and of fibrinogen, was absent. In mixing tests, patient's serum inhibited aggregation, adhesion, and PAC‐1 and A2A9/6 binding to control platelets.The patient's antibody, purified by affinity chromatography, recognized purified GPIIb by western blotting. Isolated patient's IgG inhibited platelet aggregation and A2A 9/6 binding by flow cytometry.Conclusions:Flow cytometry is especially useful for the diagnosis of aGT, being the only test able to characterize both the functional effect and the molecular target of the patient's autoantibody. © 2008 Clinical Cytometry Society
Determination of P‐glycoprotein, MDR‐related protein 1, breast cancer resistance protein, and lung‐resistance protein expression in leukemic stem cells of acute myeloid leukemia
Authors: de Figueiredo‐Pontes Lorena L. , Pintão Maria‐Carolina T. , Oliveira Luciana C. O. , Dalmazzo Leandro F. F. , Jácomo Rafael H. , Garcia Aglair B. , Falcão Roberto P. , Rego Eduardo M. 
Published: January 2008

AbstractBackground:The most primitive leukemic precursor in acute myeloid leukemia (AML) is thought to be the leukemic stem cell (LSC), which retains the properties of self‐renewal and high proliferative capacity and quiescence of the hematopoietic stem cell. LSC seems to be immunophenotypically distinct and more resistant to chemotherapy than the more committed blasts. Considering that the multidrug resistance (MDR) constitutive expression may be a barrier to therapy in AML, we have investigated whether various MDR transporters were differentially expressed at the protein level by different leukemic subsets.Methods:The relative expression of the drug‐efflux pumps P‐gp, MRP, LRP, and BCRP was evaluated by mean fluorescence index (MFI) and the Kolmogorov‐Smirnov analysis (D values) in five leukemic subpopulations: CD34+CD38−CD123+ (LSCs), CD34+CD38+CD123−, CD34+CD38+CD123+, CD34+CD38+CD123−, and CD34− mature cells in 26 bone marrow samples of CD34+ AML cases.Results:The comparison between the two more immature subsets (LSC versus CD34+CD38−CD123− cells) revealed a higher P‐gp, MRP, and LRP expression in LSCs. The comparative analysis between LSCs and subsets of intermediate maturation (CD34+CD38+) demonstrated the higher BCRP expression in the LSCs. In addition, P‐gp expression was also significantly higher in the LSC compared to CD34+CD38+CD123− subpopulation. Finally, the comparative analysis between LSC and the most mature subset (CD34−) revealed higher MRP and LRP and lower P‐gp expression in the LSCs.Conclusions:Considering the cellular heterogeneity of AML, the higher MDR transporters expression at the most immature, self‐renewable, and quiescent LSC population reinforces that MDR is one of the mechanisms responsible for treatment failure. © 2008 Clinical Cytometry Society.
MHC‐restricted T cell receptor signaling is required for αβ TCR replacement of the pre T cell receptor
Authors: Croxford Andrew L. , Akilli‐Ozturk Özlem , Rieux‐Laucat Frederic , Förster Irmgard , Waisman Ari , Buch Thorsten 
Published: January 2008

AbstractA developmental block is imposed on CD25+CD44– thymocytes at the β‐selection checkpoint in the absence of the pre T cell receptor (preTCR) α‐chain, pTα. Early surface expression of a transgenic αβ TCR has been shown to partially circumvent this block, such that thymocytes progress to the CD4+CD8+ double‐positive stage. We wanted to analyze whether a restricting MHC element is required for αβ TCR‐expressing double‐negative (DN) thymocytes to overcome the developmental block in pTα‐deficient animals. We used the HY‐I knock‐in model that endows thymocytes with αβ TCR expression in the DN compartment but has the advantage of physiological expression levels, in contrast to conventional TCR transgenes. On a pTα‐deficient background, this HY‐I TCR transgene ‘rescued’ CD25+CD44– thymocytes from apoptosis and enabled progression to later differentiation stages. On a non‐selecting MHC background, however, pTα‐deficient HY‐I mice presented a pronounced reduction in numbers of splenocytes and thymocytes when compared to animals of selecting MHC genotype, showing that MHC restriction is necessary to drive HY‐TCR‐mediated rescue of pTα‐deficient thymocytes.
Opposing regulation of T cell function by Egr‐1/NAB2 and Egr‐2/Egr‐3
Authors: Collins Sam , Lutz Michael A. , Zarek Paul E. , Anders Robert A. , Kersh Gilbert J. , Powell Jonathan D. 
Published: January 2008

AbstractTCR‐induced NF‐AT activation leads to the up‐regulation of multiple genes involved in T cell anergy. Since NF‐AT is also involved in T cell activation, we have endeavored to dissect TCR‐induced activating and inhibitory genetic programs. This approach revealed roles for the early growth response (Egr) family of transcription factors and the Egr coactivator/corepressor NGFI‐A‐binding protein (NAB)2 in regulating T cell function. TCR‐induced Egr‐1 and NAB2 enhance T cell function, while Egr‐2 and Egr‐3 inhibit T cell function. In this report, we demonstrate that Egr‐2 and Egr‐3 are induced by NF‐AT in the absence of AP‐1, while Egr‐1 and NAB2 both require AP‐1‐mediated transcription. Our data suggest that Egr‐3 is upstream of Egr‐2, and that mechanistically Egr‐2 and Egr‐3 suppress Egr‐1 and NAB2 expression. Functionally, T cells from Egr‐2 and Egr‐3 null mice are hyperresponsive while T cells from Egr‐3 transgenic, overexpressing mice are hyporesponsive. Furthermore, an in vivo model of autoimmune pneumonitis reveals that T cells from Egr‐3 null mice hasten death while Egr‐3‐overexpressing T cells cause less disease. Overall, our data suggest that just as the Egr/NAB network of genes control cell fate in other systems, TCR‐induced Egr‐1, 2, 3 and NAB2 control the fate of antigen recognition in T cells.
Unexpected regulatory roles of TLR4 and TLR9 in experimental autoimmune encephalomyelitis
Authors: Marta Monica , Andersson Åsa , Isaksson Magnus , Kämpe Olle , Lobell Anna 
Published: January 2008

AbstractInnate immune mechanisms essential for priming encephalitogenic T cells in autoimmune neuroinflammation are poorly understood. Experimental autoimmune encephalomyelitis (EAE) is a IL‐17‐producing Th (Th17) cell‐mediated autoimmune disease and an animal model of multiple sclerosis. To investigate how upstream TLR signals influence autoimmune T cell responses, we studied the role of individual TLR and MyD88, the common TLR adaptor molecule, in the initiation of innate and adaptive immune responses in EAE. Wild type (WT) C57BL/6, TLR‐deficient and MyD88‐deficient mice were immunized with myelin oligodendrocyte glycoprotein (MOG) in CFA. MyD88–/– mice were completely EAE resistant. Purified splenic myeloid DC (mDC) from MyD88–/– mice expressed much less IL‐6 and IL‐23, and serum and T cell IL‐17 were absent. TLR4–/– and TLR9–/– mice surprisingly exhibited more severe EAE symptoms than WT mice. IL‐6 and IL‐23 expression by mDC and Th17 responses were higher in TLR4–/– mice, suggesting a regulatory role of TLR4 in priming Th17 cells. IL‐6 expression by splenocytes was higher in TLR9–/– mice. Our data suggest that MyD88 mediates the induction of mDC IL‐6 and IL‐23 responses after MOG immunization, which in turn drives IL‐17‐producing encephalitogenic Th17 cell activation. Importantly, we demonstrate that TLR4 and TLR9 regulate disease severity in MOG‐induced EAE.
Mannose‐capped lipoarabinomannan‐ and prostaglandin E2‐dependent expansion of regulatory T cells in human Mycobacterium tuberculosis infection
Authors: Garg Ankita , Barnes Peter F. , Roy Sugata , Quiroga María F. , Wu Shiping , García Verónica E. , Krutzik Stephan R. , Weis Steven E. , Vankayalapati Ramakrishna 
Published: January 2008

AbstractWe evaluated the role of regulatory T cells (CD4+ CD25+ Foxp3+ cells, Tregs) in human Mycobacterium tuberculosis infection. Tregs were expanded in response to M. tuberculosis in healthy tuberculin reactors, but not in tuberculin‐negative individuals. The M. tuberculosis mannose‐capped lipoarabinomannan (ManLAM) resulted in regulatory T cell expansion, whereas the M. tuberculosis 19‐kDa protein and heat shock protein 65 had no effect. Anti‐IL‐10 and anti‐TGF‐β alone or in combination, did not reduce expansion of Tregs. In contrast, the cyclooxygenase enzyme‐2 inhibitor NS398 significantly inhibited expansion of Tregs, indicating that prostaglandin E2 (PGE2) contributes to Treg expansion. Monocytes produced PGE2 upon culturing with heat‐killed M. tuberculosis or ManLAM, and T cells from healthy tuberculin reactors enhanced PGE2 production by monocytes. Expanded Tregs produced significant amounts of TGF‐β and IL‐10 and depletion of Tregs from PBMC of these individuals increased the frequency of M. tuberculosis‐responsive CD4+ IFN‐γ cells. Culturing M. tuberculosis‐expanded Tregs with autologous CD8+ cells decreased the frequency of IFN‐γ+cells. Freshly isolated PBMC from tuberculosis patients had increased percentages of Tregs, compared to healthy tuberculin reactors. These findings demonstrate that Tregs expand in response to M. tuberculosis through mechanisms that depend on ManLAM and PGE2.