bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of binding constants of cyclodextrin inclusion complexes with amino acids and dipeptides by potentiometric titration
Authors: Kahle Claudia , Holzgrabe Ulrike 
Published: July 2004

AbstractCyclodextrins are well known for their ability to separate enantiomers of drugs, natural products, and other chiral substances using HPLC, GC, or CE. The resolution of the enantiomers is due to the formation of diastereomeric complexes between the cyclodextrin and the pairs of enantiomers. The aim of this study was to determine the binding constants of the complexes between α‐ and β‐cyclodextrin and the enantiomers of a series of aliphatic and aromatic amino acids, and dipeptides, using a potentiometric titration method. The results of this method are compared to other methods, and correlated to findings in cyclodextrin‐modified capillary electrophoresis and possible complex structures. Potentiometric titration was found to be an appropriate tool to determine the binding constants of cyclodextrin inclusion complexes. Chirality 16:509–515, 2004. © 2004 Wiley‐Liss, Inc.
Free circulating soluble CD52 as a tumor marker in chronic lymphocytic leukemia and its implication in therapy with anti‐CD52 antibodies
Authors: Albitar Maher , Do Kim‐Anh , Johnson Marcella M. , Giles Francis J. , Jilani Iman , O'Brien Susan , Cortes Jorge , Thomas Deborah , Rassenti Laura Z. , Kipps Thomas J. , Kantarjian Hagop M. , Keating Michael 
Published: July 2004

AbstractBACKGROUNDThe CD52 antigen is a glycoprotein anchored on the cell membrane of mature B and T lymphocytes, monocytes, and eosinophils. Alemtuzumab (CAMPATH‐1H; anti‐CD52) is currently approved for the treatment of patients with refractory chronic lymphocytic leukemia (CLL). The authors investigated the possibility that CD52 may be shed from cells and, once soluble, may bind to injected alemtuzumab, forming immune complexes.METHODSThe authors used Western blot analysis, immunoprecipitation, and enzyme‐linked immunoadsorbent assay to investigate the presence of soluble CD52 (sCD52) in the plasma specimens of 117 patients with CLL. They also used in vitro mixing experiments to examine the ability of sCD52 to compete with cells and sequester therapeutic alemtuzumab.RESULTSThe authors detected high levels of sCD52 in the plasma specimens of patients with CLL. sCD52 can compete with cells in vitro for binding to alemtuzumab, and can form complexes in patients receiving alemtuzumab. Plasma levels of sCD52 were found to be correlated (r)with Rai stage (P = 0.0001), β‐2‐microglobulin (β‐2M) levels (P = 0.00002), soluble CD23 levels (r = 0.42, P < 0.001), and immunoglobulin mutation status (P = 0.003). In the multivariate analysis adjusted for β‐2M level, patients with sCD52 levels > 2336 nM/L had a nearly 4‐fold increase in risk of death. Higher levels of plasma alemtuzumab were achieved when levels of sCD52 were lower.CONCLUSIONSThese data not only demonstrated that sCD52 was detectable and useful in the staging and monitoring of patients with CLL, but also showed that sCD52 formed immune complexes with alemtuzumab and may influence the efficacy and toxicity of alemtuzumab therapy. Cancer 2004. © 2004 American Cancer Society.
Solution of clamped rectangular plate problems
Authors: Taylor Robert L. , Govindjee Sanjay 
Published: July 2004

AbstractIn this brief note, we present an efficient scheme for determining very accurate solutions to the clamped rectangular plate problem. The method is based upon the classical double cosine series expansion and an exploitation of the Sherman–Morrison–Woodbury formula. If the cosine expansion involves M terms and N terms in the two plate axes directions, then the classical method for this problem involves solving a system of (MN) × (MN) equations. Our proposal reduces the problem down to a system of well‐conditioned N × N equations (or M × M when M < N). Numerical solutions for rectangular plates with various side ratios are presented and compared to the solution generated via Hencky's method. Corrections to classical results and additional digits for use in finite‐element convergence studies are given. As an application example, these are used to show the rate of convergence for thin plate finite‐element solutions computed using the Bogner–Fox–Schmit element. Copyright © 2004 John Wiley & Sons, Ltd.
An efficient shape‐preserving curve fitting technique for complex structures
Authors: Hyun Seokjeong , Kim Cheol 
Published: July 2004

AbstractAn efficient curve fitting technique has been developed to preserve the shape of complex structures. A shape‐preserving curve fitting technique is frequently used in a mesh generation or a shape optimization process. Perturbations during the curve fitting process often appear if the shape of a structure is complex or if the data points are positioned irregularly. The proposed technique represents more precise and smoother surfaces than using conventional B‐spline curves. Several comparisons are made and results show the superiority of the proposed technique over B‐spline curves. Copyright © 2004 John Wiley & Sons, Ltd.
Early development of children at familial risk for Dyslexia—follow‐up from birth to school age
Authors: Lyytinen H. , Ahonen T. , Eklund K. , Guttorm T. , Kulju P. , Laakso M.‐L. , Leiwo M. , Leppänen P. , Lyytinen P. , Poikkeus A.‐M. , Richardson U. , Torppa M. , Viholainen H. 
Published: July 2004

AbstractWe review the main findings of the Jyväskylä of Dyslexia (JLD) which follows the development of children at familial risk for dyslexia (N = 107) and their controls (N = 93). We will illustrate the development of these two groups of children at ages from birth to school entry in the skill domains that have been connected to reading and reading disability in the prior literature. At school entry, the highest score on the decoding task among the poorer half (median) of the at risk children—i.e. of those presumably being most likely genetically affected—is 1 SD below the mean of the control group. Thus, the familial risk for dyslexia shows expected consequences. Among the earliest measures in which group differences as well as significant predictive associations with the first steps in reading have emerged, are indices of speech processing in infancy. Likewise, various measures of early language including pronunciation accuracy, phonological, and morphological skills (but not performance IQ) show both group differences and predictive correlations, the majority of which become stronger as the reliability of the measures increases by age. Predictive relationships tend to be strong in general but higher in the at risk group because of its larger variance in both the predictor variables and in the dependent measures, such as early acquisition of reading. The results are thus promising in increasing our understanding needed for early identification and prevention of dyslexia. Copyright © 2004 John Wiley & Sons, Ltd.
Antibody‐mediated activation of the classical pathway of complement may compensate for mannose‐binding lectin deficiency
Authors: Roos Anja , Garred Peter , Wildenberg Manon E. , Lynch Nicholas J. , Munoz Jeric R. , Zuiverloon Tahlita C.M. , Bouwman Lee H. , Schlagwein Nicole , van den Houten Francien C. Fallaux , Faber‐Krol Maria C. , Madsen Hans O. , Schwaeble Wilhelm J. , Matsushita Misao , Fujita Teizo , Daha Mohamed R. 
Published: July 2004

AbstractDeficiency of mannose‐binding lectin (MBL), a recognition molecule of the lectin pathway of complement, is associated with increased susceptibility to infections. The high frequency of MBL deficiency suggests that defective MBL‐mediated innate immunity can be compensated by alternative defense strategies. To examine this hypothesis, complement activation by MBL‐binding ligands was studied. The results show that the prototypic MBL ligand mannan can induce complement activation via both the lectin pathway and the classical pathway. Furthermore, antibody binding to mannan restored complement activation in MBL‐deficient serum in a C1q‐dependent manner. Cooperation between the classical pathway and the lectin pathway was also observed for complement activation by protein 60 from Listeria monocytogenes. MBL pathway analysis at the levels of C4 and C5b–9 in the presence of classical pathway inhibition revealed a large variation of MBL pathway activity, depending on mbl2 gene polymorphisms. MBL pathway dysfunction in variant allele carriers is associated with reduced MBL ligand binding and a relative increase of low‐molecular‐mass MBL. These findings indicate that antibody‐mediated classical pathway activation can compensate for impaired target opsonization via the MBL pathway in MBL‐deficient individuals, and imply that MBL deficiency may become clinically relevant in absence of a concomitant adaptive immune response.
Peritoneal B cells govern the outcome of diabetes in non‐obese diabetic mice
Authors: Kendall Peggy L. , Woodward Emily J. , Hulbert Chrys , Thomas James W. 
Published: July 2004

AbstractType 1 diabetes mellitus (T1DM) results from autoimmune destruction of insulin‐producing beta cells in the pancreatic islets. Although T1DM is mediated by T lymphocytes, B lymphocytes are essential for insulitis and disease progression in the non‐obese diabetic mouse model. We find that B cells invading the pancreas phenotypically resemble B1a B cells in the peritoneal cavity, including the presence of CD5+. To investigate the link between the peritoneal cavity and lymphocytes invading the pancreas, we used intraperitoneal hypotonic lysis to target these cells. B1a cells were eliminated from the peritoneal compartment by this treatment and were quickly replaced by B2 cells. Both B1a and B2 B cells were concordantly redistributed away from insulitis lesions, while pancreatic T cells showed little change. As a consequence of these events, the onset of diabetes was significantly delayed. These findings indicate that simple perturbations of the B cell‐enriched peritoneal compartment can affect the disease process in the pancreas even after islet invasion has begun.
Partial activation precedes apoptotic death in T cells harboring an IAN gene mutation
Authors: Lang Julie A. , Kominski Douglas , Bellgrau Donald , Scheinman Robert I. 
Published: July 2004

AbstractThe Biobreeding diabetes‐prone rat suffers from a profound peripheral lymphopenia and yet succumbs to a T cell‐dependent autoimmune disease. Lymphopenia segregates with a mutated chromosomal locus, termed lyp, recently identified as a frameshift mutation in IAN4. Others have correlated loss of IAN4 function with decreased mitochondrial integrity resulting in T cell apoptosis. Here we report that IAN4–/– T cells enter a state similar to that of partial activation wherein they down‐regulate CD62L and undergo incomplete blasting yet do not progress through mitosis. When given a strong stimulus, this partial activation phenotype can be overcome. This phenotype can be recapitulated in wild‐type T cells through suboptimal stimulation. The phenotype is not simply a reaction to the lymphopenic environment, as spontaneous CD62L down‐regulation occurs in mature single‐positive medullary thymocytes that develop within a non‐lymphopenic environment, and normal T cells do not undergo similar blasting when parked in a lymphopenic environment. Finally, we show that IAN4–/– T cells are more readily triggered via TCR stimulation. Thus, in addition to their role in apoptosis, IAN family members may also play a role in regulating the T cell activation state through modulation of TCR signaling strength.
Tc2 cells respond to soluble antigen in the respiratory tract and induce lung eosinophilia and bronchial hyperresponsiveness
Authors: Sawicka Elzbieta , Noble Alistair , Walker Christoph , Kemeny David M. 
Published: July 2004

AbstractThe key role of T helper 2 (Th2) cells in asthma is well established. In contrast, the function of CD8+ T cells producing a distinct cytokine profile similar to Th2 cells is largely unknown. To analyze a potential role of CD8+ T cell subsets, allergen‐specific, in vitro‐differentiated T cytotoxic (Tc1 or Tc2) cells from T cell receptor transgenic OT‐I mice were adoptively transferred into naive C57BL/6 mice. Subsequent allergen challenge of mice injected with Tc1 cells (producing IFN‐γ but no IL‐4) resulted in a neutrophilic airway inflammation without induction of bronchial hyperresponsiveness (BHR). In contrast, the inflammatory response of recipients of adoptively transferred Tc2 cells (producing high levels of IL‐4 but little IFN‐γ) was characterized by significantly increased numbers of eosinophils and induction of BHR to methacholine. The response of antigen‐specific CD8+ T cells to soluble antigen was also observed in an in vitro system. A low concentration of antigen was shown to favor the generation of Tc2 cells, whereas high antigen load resulted in the differentiation of Tc1 cells. Thus, allergen‐specific Tc2 cells respond to inhaled soluble antigen, produce an inflammatory response qualitatively similar to Th2 cells and therefore may exacerbate the Th2‐driven airway inflammation in asthma.
Complement activation by necrotic cells in normal plasma environment compares to that by late apoptotic cells and involves predominantly IgM
Authors: Ciurana Caroline L. F. , Zwart Bas , van Mierlo Gerard , Hack C. Erik 
Published: July 2004

AbstractNecrotic cells are generally considered to stimulate inflammation, whereas apoptotic cells should not. However, apoptotic cells have pro‐inflammatory properties since they can activate complement. To what extent this activation compares to that by necrotic cells is not known. We compared complement activation by necrotic cells and apoptotic cells in plasma. Jurkat cells were made apoptotic or necrotic by incubation with etoposide or by heat shock, respectively. Cells incubated in recalcified plasma were tested for C3 and C4 fixation and fluid phase generation of complement activation products. Fixation of C3 and C4 to necrotic cells occurred mainly via the classical pathway, independent from the method of necrosis induction and the cell type. Depletion of IgM from plasma almost completely abrogated complement fixation by necrotic cells, which was restored by supplementation with purified IgM. Complement activation by late apoptotic cells was comparable to that by necrotic cells regarding the extent and dependence on IgM. Moreover, incubation of plasma with necrotic or late apoptotic cells led to the generation of comparable amounts of complement activation products. These results indicate that late apoptotic and necrotic cells employ similar complement activation mechanisms in the plasma environment.
Self‐Assembly of Stereoselective, Mononuclear, Triple‐Stranded Helicate Complexes ML3 with Trivalent Scandium and Lanthanide Metal Ions − Quantitative Transmetallation of the Lanthanide(III) Ion by Sodium(I) Ions
Authors: Capó Magdalena , Gonzalez José , Adams Harry 
Published: July 2004

AbstractMononuclear triple‐stranded helicate complexes ML3 (M = Sc3+, La3+, Sm3+, Yb3+) were self‐assembled and structurally characterized by NMR spectroscopy and high‐resolution mass spectrometry. The solid‐state structure of the ytterbium complex was determined by X‐ray crystallography. The core lanthanide metal ion was replaced quantitatively by three sodium ions. Homo‐ and heterotrinuclear complexes containing the alkali metal ions Li+ and Na+ were obtained from the mononuclear lanthanide complexes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Chemical Synthesis of GPIs and GPI‐Anchored Glycopeptides
Authors: Guo Zhongwu , Bishop Lee 
Published: July 2004

AbstractThis microreview summarizes some recent progress in the study of glycosylphosphatidylinositols (GPI), focusing on the strategies established for the synthesis of optically pure myo‐inositol derivatives and complex GPIs and GPI conjugates. Although in the past decade many GPIs have been achieved by linear, convergent and solid‐phase synthesis, the GPIs with 2‐O‐acylated inositol residues and the GPI conjugates of peptides and glycopeptides have not been accomplished until recently. The successful coupling of peptides and glycopeptides to GPIs brings new promises to this area, but the scope of the relevant designs, in particular their application to more complex structures such as GPI‐anchored glycoproteins, remains untested. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Stereo‐ and Regiocontrol in the Formation of Lactams by Rhodium‐Carbenoid C−H Insertion of α‐Diazoacetamides
Authors: Gois Pedro M. P. , Afonso Carlos A. M. 
Published: July 2004

AbstractThe dirhodium(II)‐catalysed intramolecular C−H insertion reaction of α‐diazoacetamides is a powerful methodology for the preparation of highly valuable heterocyclic compounds such as lactams. In this Microreview we present lactam formation by intramolecular C−H insertion of α‐diazoacetamides, focusing on the effects that have a profound impact on the reaction pathway. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Catalytic Effect on Silver Electrodeposition of Gold Deposited on Carbon Electrodes
Authors: de la Escosura‐Muñiz Alfredo , Begoña González‐García María , Costa‐García Agustín 
Published: July 2004

AbstractA new methodology, based on silver electrocatalytic deposition and designed to quantify gold deposited onto carbon paste electrode (CPE) and glassy carbon electrode (GCE), has been developed in this work. Silver (prepared in 1.0 M NH3) electrodeposition at −0.13 V occurs only when gold is previously deposited at an adequate potential on the electrode surface for a fixed period of time. When a CPE is used as working electrode, an adequate oxidation of gold is necessary. This oxidation is carried out in both 0.1 M NaOH and 0.1 M H2SO4 at oxidation potentials. When a GCE is used as working electrode, the oxidation steps are not necessary. Moreover, a cleaning step in KCN, which removes gold from electrode surface, is included. To obtain reproducibility in the analytical signal, the surface of the electrodes must be suitably pretreated; this electrodic pretreatment depends on the kind of electrode used as working electrode. Low detection limits (5.0×10−10 M) for short gold deposition times (10 min for CPE and 5 min for GCE) were achieved with this novel methodology. Finally, sodium aurothiomalate can be quantified using silver electrocatalytic deposition and GCE as working electrode. Good linear relationship between silver anodic stripping peak and aurothiomalate concentration was found from 5.0×10−10 M to 1.0×10−8 M.
A New Nitric Oxide Gas Sensor Based on Reticulated Vitreous Carbon/Nafion and Its Applications
Authors: Sun Jie , Hauser Peter C. , Zhelyaskov Valentine , Lin Jie , Broderick Mark , Fein Harry , Zhang Xueji 
Published: July 2004

AbstractReticulated vitreous carbon (RVC), and Nafion membrane are used to fabricate a composition electrode to measure nitric oxide (NO) concentration amperometrically in the gas phase. Limit of detection was found to be 6 ppb at an applied voltage of 0.66 V (vs. mercury sulfate reference electrode) with average response time of less than 30 seconds. The response of the sensor was linearly dependent on the concentration over the whole tested range from 19 ppb‐50 ppm of NO. Simplicity in electrode fabrication and consistent performance between individual sensors make RVC and Nafion attractive materials for detecting very low levels of nitric oxide gas in routine analysis.
Bioelectrocatalysis of Oxygen Reduction Reaction by Laccase on Gold Electrodes
Authors: Gupta Gautam , Rajendran Vijaykumar , Atanassov Plamen 
Published: July 2004

AbstractDirect electron transfer (DET) reaction of oxygen electroreduction catalyzed by enzyme laccase on monolayer modified gold electrodes was studied. Three different monolayers were investigated, from which 4‐aminothiophenol was found to be optimal for the direct electron transfer to take place. The electrocatalytic reduction of the oxygen at the electrode surface was found to depend significantly on the method of immobilization. Fungal laccase from Coriolus hirsitus modified with sodium‐periodate demonstrated more anodic onset potential for oxygen reduction than the tree laccase from Rhus vernicifera. Physical immobilization of enzyme did not result in any manifestation of bioelectrocatalytic activity. A maximum anodic shift in reduction potential of 300 mV was observed for fungal laccase covalently coupled on the electrode surface.
Catalytic Oxidation of Ascorbic Acid on 2D and 3D Monolayers of 4‐Hydroxythiophenol
Authors: Stolarczyk Krzysztof , Bilewicz Renata 
Published: July 2004

AbstractMonolayers of 4‐hydroxythiophenol (4‐HTP) immobilized on gold electrode (2D SAMs) or gold nanoclusters (3D SAMs) lead to catalytic oxidation of ascorbic acid (AA). The catalytic role of the modified clusters was revealed by comparing the electrodes covered by 1,9‐nonanedithiol and the same nonanedithiol monolayer decorated by 4‐HTP protected clusters. The 4‐HTP protected gold nanoclusters supported on a metal surface using a monolayer of 1,9‐nonanedithiol as the bridge, transferred charge to ascorbic acid (AA) molecule in the solution more efficiently than when the same 4‐HTP monolayer was formed directly on the gold electrode.
Two‐step elution of human serum proteins from different glass‐modified bioactive surfaces: A comparative proteomic analysis of adsorption patterns
Authors: Magnani Agnese , Barbucci Rolando , Lamponi Stefania , Chiumento Antonio , Paffetti Alessandro , Trabalzini Lorenza , Martelli Paola , Santucci Annalisa 
Published: July 2004

AbstractPlasma protein adsorption patterns on surfaces may give vital information to evaluate biocompatibility of biomaterials designed for direct blood‐contacting applications or tissue integration. Adsorption of human serum proteins on four different types of biomaterials (glass, aminosilanized glass, hyaluronan and sulfated hyaluronan) was analyzed by two‐dimensional electrophoresis. Desorption of proteins from the surfaces was first classically achieved by sodium dodecyl sulfate (SDS) elution. We introduced a second elution step (by use of isoelectric focusing (IEF) sample buffer consisting of urea, 3‐[(3‐cholamidopropyl)dimethylammonio]‐1‐propansulfonate, and dithioerythritol) which allows more stringent elution conditions and is a tool to evaluate the protein adsorption strength to biomaterials. Moreover, the two‐step elution may discriminate between irreversible and reversible adsorption of plasma proteins for biomaterials, thus helping to elucidate the structure of protein multilayers which form a complex system at the surfaces. The IEF sample buffer proved not to alter the biomaterial structure and integrity. Hydrophobic bonds resulted to be the main strength driving protein adsorption onto our biomaterials. Apolipoproteins were the most important proteins interacting with the surfaces suggesting that high‐density lipoprotein (HDL) particles could play a role in biocompatibility due to their beneficial effects on endothelial cells.