bluuebunny/crossref_metadata_2025_split huggingface dataset:
Glycoforms of human endothelial CD34 that bind L-selectin carry sulfated sialyl Lewis x capped O- and N-glycans
Authors: Mir Gerard Hernandez , Helin Jari , Skarp Kari-Pekka , Cummings Richard D. , Mäkitie Antti , Renkonen Risto , Leppänen Anne 
Published: April 2009

AbstractEndothelial sialomucin CD34 functions as an L-selectin ligand mediating lymphocyte extravasation only when properly glycosylated to express a sulfated carbohydrate epitope, 6-sulfo sialyl Lewis x (6-sulfo SLex). It is thought that multivalent 6-sulfo SLex expression promotes high-affinity binding to L-selectin by enhancing avidity. However, the reported low amount of 6-sulfo SLex in total human CD34 is inconsistent with this model and prompted us to re-evaluate CD34 glycosylation. We separated CD34 into 2 glycoforms, the L-selectin–binding and nonbinding glycoforms, L-B-CD34 and L-NB-CD34, respectively, and analyzed released O- and N-glycans from both forms. L-B-CD34 is relatively minor compared with L-NB-CD34 and represented less than 10% of total tonsillar CD34. MECA-79, a mAb to sulfated core-1 O-glycans, bound exclusively to L-B-CD34 and this form contained all sulfated and fucosylated O-glycans. 6-Sulfo SLex epitopes occur on core-2 and extended core-1 O-glycans with approximately 20% of total L-B-CD34 O-glycans expressing 6-sulfo SLex. N-glycans containing potential 6-sulfo SLex epitopes were also present in L-B-CD34, but their removal did not abolish binding to L-selectin. Thus, a minor glycoform of CD34 carries relatively abundant 6-sulfo SLex epitopes on O-glycans that are important for its recognition by L-selectin.
Molecular Determinants of Grb14-Mediated Inhibition of Insulin Signaling
Authors: Goenaga Diana , Hampe Cornelia , Carré Nadège , Cailliau Katia , Browaeys-Poly Edith , Perdereau Dominique , Holt Lowenna J. , Daly Roger J. , Girard Jean , Broutin Isabelle , Issad Tarik , Burnol Anne-Françoise 
Published: April 2009

AbstractGrb14 belongs to the Grb7 family of molecular adapters and was identified as an inhibitor of insulin signaling. Grb14 binds to activated insulin receptors (IR) and inhibits their catalytic activity. To gain more insight into the Grb14 molecular mechanism of action, we generated various mutants and studied the Grb14-IR interaction using coimmunoprecipitation and bioluminescence resonance energy transfer (BRET) experiments. Biological activity was further analyzed using the Xenopus oocyte model and a functional complementation assay measuring cellular proliferation rate in Grb14 knockout mouse embryonic fibroblasts. These studies identified two important interaction sites, Grb14 L404-IR L1038 and Grb14 R385-IR K1168, involving the IR αC-helix and activation loop, respectively. Interestingly, the former involves residues that are likely to be crucial for the specificity of IR binding with regard to other members of the Grb7 family. In addition, mutation of the Grb14-S370 residue suggested that its phosphorylation status controlled the biological activity of the protein. We further demonstrated that insulin-induced Grb14-PDK1 interaction is required in addition to Grb14-IR binding to mediate maximal inhibition of insulin signaling. This study provides important insights into the molecular determinants of Grb14 action by demonstrating that Grb14 regulates insulin action at two levels, through IR binding and by interfering with downstream pathways. Indeed, a precise knowledge of the molecular mechanism of insulin signaling inhibition by Grb14 is a prerequisite for the development of insulin-sensitizing molecules to treat pathophysiological states such as obesity or type 2 diabetes.
A Ferromagnetic Chain of Imidazolato-Bridged One-Dimensional Copper(II) Complex
Authors: Yoshida Tetsuya , Towatari Masaaki , Sato Tetsuya , Matsumoto Naohide , Re Nazzareno , Mrozinski Jerzy 
Published: April 2009

Abstract
A mononuclear copper(II) complex, [2-ethoxy-6-{[3-(2-methyl-4-imidazolylmethyleneamino)propyl]iminomethyl}phenolato]copper(II) perchlorate [CuHL]ClO4 and its deprotonated complex at the imidazole moiety, [CuL]n, were prepared. The structure of [CuHL]ClO4 consists of a cation [CuHL]+ exhibiting a four-coordinated square-planar geometry and an anion ClO4−, while [CuL]n assumes an imidazolato-bridged zigzag-chain structure, in which the copper(II) ion is coordinated by the imidazolato nitrogen atom of the adjacent molecule with Cu–N = 2.258(5) Å and the two adjacent CuL units assumes a perpendicular orientation. The temperature-dependent magnetic susceptibilities from 2.0 to 300 K and field-dependent magnetization at 2.0 K demonstrate that [CuHL]ClO4 is a magnetically isolated copper(II) molecule while [CuL]n is a ferromagnetic chain. The magnetic susceptibility data of [CuL]n were analyzed by Baker’s model based on H = −2JΣSAjSAj+1 for chain of equally spaced copper(II) ions to give the best-fit parameters of g = 2.08 and J = +0.63 cm−1.
Photolysis of Indan-1,2-dione Derivatives in Oxygen-Doped Argon Matrix at Low Temperature
Authors: Itoh Takayoshi , Tatsugi Jiro , Tomioka Hideo 
Published: April 2009

Abstract
Photolysis of indan-1,2,3-trion (1a), benzo[b]furan-2,3-dione (1b), and N-methylisatin (1c) in argon matrix either with or without oxygen at 10 K was investigated by IR spectroscopy in combination with DFT calculations. The results indicate that while 1a and 1b gave the products mixture as a result of α-cleavage, followed by decarbonylation, 1c was rather photostable under similar conditions. However, when the irradiation was carried out in argon matrix doped with 20% oxygen, 1c decomposed much more efficiently than that in argon matrix and cyclic diacyl peroxide presumably formed by trapping of initial diradical originating from α-cleavage by molecular oxygen was detected. Similar irradiation of 1b also gave cyclic diacyl peroxide along with photodecarbonylation products, but irradiation of 1a in oxygen-doped matrix produced not only cyclic diacyl peroxide but also products as a result of oxidation of photodecarbonylation product. The present observation reveals that photolysis of ketones in oxygen-doped matrix at low temperature provides useful information concerning the reactivities of ketones toward α-cleavage.
Mechanistic Study of Oxidative Aromatization Using Activated Carbon–Molecular Oxygen System in the Synthesis of 2-Arylbenzazoles: Focus on the Role of Activated Carbon
Authors: Kawashita Yuka , Yanagi Juichi , Fujii Tatsuo , Hayashi Masahiko 
Published: April 2009

Abstract
Nineteen activated carbons, including sixteen tailor-made and three commercially available ones, were employed to investigate their role in the one-pot synthesis of 2-arylbenzazoles starting from 2-aminophenol, 1,2-diaminobenzene, or 2-aminobenzenethiol, and aldehyde via oxidative cyclization of intermediate phenolic Schiff base promoted by the activated carbon–molecular oxygen system. Tailor-made activated carbons were prepared from wood, coconut shell, and coal by the steam activation method or the chemical activation method. All activated carbons were characterized to clarify their properties, such as metal contaminants, specific surface area, porosity, and surface functionality. After examining their effects on reactivity in the oxidative aromatization, we found that the essential role of activated carbon in this oxidation system is concerned not with metal contaminants, specific surface area, pore volume, mean pore diameter, and surface oxygen groups evolving as CO2 at 900 °C but with surface oxygen groups evolving as CO during heating at 900 °C, such as carbonyl groups on the surface of activated carbon. Additionally, in the synthesis of 2-arylbenzoxazole, it was found that activated carbon would also promote the cyclization of the intermediate Schiff base.
CdS Nanoparticles Exhibiting Quantum Size Effect by Dispersion on TiO2: Photocatalytic H2 Evolution and Photoelectrochemical Measurements
Authors: Ogisu Kiyonori , Takanabe Kazuhiro , Lu Daling , Saruyama Masaki , Ikeda Takahiro , Kanehara Masayuki , Teranishi Toshiharu , Domen Kazunari 
Published: April 2009

Abstract
Uniformly sized CdS nanoparticles exhibiting quantum size effect have been synthesized as a suspension in hexane solution containing oleic acid and 9-octadecenylamine as protective ligands. Our study focuses on utilizing the intrinsic optical property of the nanoparticles for photocatalytic H2 evolution and photoelectrochemical reaction by immobilizing oxide substrate and removing protective ligands. Immobilized CdS nanoparticles on TiO2 were found to maintain their original particle size and optical property after impregnation and removal of the protective ligands by oxidative heat treatment and/or alkali treatment. The photocatalytic H2 evolution rates in Na2S–Na2SO3 solution under visible light were strongly affected by the CdS particle size (quantum size effect), CdS loading amount, and TiO2 surface area. High photoanodic current was observed for CdS/TiO2 sprayed on a fluoride-doped tin oxide (FTO) electrode, functioning as an n-type semiconductor. The knowledge acquired in this study can be extended for further development in the field of nanoparticle materials covered with protective ligands.
Separating component processes of theory of mind in schizophrenia
Authors: Bailey Phoebe E. , Henry Julie D. 
Published: April 2009

Objective. It has been argued that in order to take the perspective of another the ‘default’ self‐perspective must first be inhibited. Thus, executive function failures (and specifically, reduced inhibitory control of the self‐perspective) may contribute to the theory of mind (ToM) difficulties that have been observed in schizophrenia.Method. Participants with schizophrenia (N=28) and demographically matched controls (N=30) were administered a behavioural measure of ToM that directly manipulates inhibitory demands by involving either high‐ or low‐levels of self‐perspective inhibition.Results. Relative to controls, participants with schizophrenia demonstrated impaired ToM, but did not have particular difficulty on the task that placed high demands on self‐perspective inhibition.Conclusion. Disruption of other‐perspective taking, rather than self‐perspective inhibition, appears to be the more important determinant of ToM impairment in schizophrenia. This finding is discussed in relation to competing perspectives of ToM.
Thermodynamic and thermophysical properties of the reference ionic liquid: 1-Hexyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]amide (including mixtures). Part 1. Experimental methods and results (IUPAC Technical Report)
Authors: Marsh Kenneth N. , Brennecke Joan F. , Chirico Robert D. , Frenkel Michael , Heintz Andreas , Magee Joseph W. , Peters Cor J. , Rebelo Luis Paulo N. , Seddon Kenneth R. 
Published: April 2009

Abstract
This article summarizes the results of IUPAC Project 2002-005-1-100 (Thermodynamics of ionic liquids, ionic liquid mixtures, and the development of standardized systems). The methods used by the various contributors to measure the thermophysical and phase equilibrium properties of the reference sample of the ionic liquid 1-hexyl-3-methylimidazolium bis [(trifluoromethyl)sulfonyl]amide and its mixtures are summarized along with the uncertainties estimated by the contributors. Some results not previously published are presented. Properties of the pure ionic liquid included thermal properties (triple-point temperature, glass-transition temperature, enthalpy of fusion, heat capacities of condensed states), volumetric properties, speeds of sound, viscosities, electrolytic conductivities, and relative permittivities. Properties for mixtures included gas solubilities, solute activity coefficients at infinite dilution, liquid-liquid equilibrium temperatures, and excess volumes. The companion article (Part 2) provides a critical evaluation of the data and recommended values with estimated combined expanded uncertainties.
Traceability in Laboratory Medicine
Authors: Vesper Hubert W , Thienpont Linda M 
Published: April 2009

AbstractBackground: In patient and population samples, generation of analytical results that are comparable and independent of the measurement system, time, and location is essential for the utility of laboratory information supplied in healthcare. Obtaining analytical measurement results with such characteristics is the aim of traceability in laboratory medicine. As awareness of the benefits of having traceable measurement results has increased, associated efforts have been directed toward making traceability a regulatory requirement and developing approaches to enable and facilitate the implementation of traceability. Although traceability has been a main focus of many laboratory standardization activities in the past, discussions are still ongoing with regard to traceability and its implementation.Content: This review provides information about the traceability concept and what needs can be fulfilled and benefits achieved by the availability of traceable measurement results. Special emphasis is given to the new metrological terminology introduced with this concept. The review addresses and describes approaches for technical implementation of traceable methods as well as the associated challenges. Traceability is also discussed in the context of other activities to improve the overall measurement process.Summary: Establishing metrological traceability of measurement results satisfies basic clinical and public health needs, thus improving patient care and disease control and prevention. Large advances have been made to facilitate the implementation of traceability. However, details in the implementation process, such as lack of available commutable reference materials and insufficient resources to develop new reference measurement systems continue to challenge the laboratory medicine community.
Liquid Chromatography–Tandem Mass Spectrometry Analysis of Folate and Folate Catabolites in Human Serum
Authors: Hannisdal Rita , Ueland Per Magne , Svardal Asbjørn 
Published: April 2009

Abstract
Background: Folate status is associated with several chronic diseases; thus accurate assessment of folate status has become important in the clinical setting and in epidemiological studies. The diversity of folate forms complicates the task of assaying endogenous folate. We developed and validated an assay that measures various forms of folate in addition to folate catabolites in human serum.
Methods: We added ascorbic acid to serum samples from 168 healthy blood donors and 39 patients with renal failure, and precipitated the proteins with acetonitrile containing 13C-labeled folate forms as internal standards. The supernatant was evaporated and the analytes redissolved in water. We then used liquid chromatography–tandem mass spectrometry to quantify 5-methyltetrahydrofolate (5mTHF), 4-α-hydroxy-5-methyltetrahydrofolate (hmTHF), folic acid (FA), 5-formyltrahydrofolate (5fTHF), p-aminobenzoylglutamate (pABG), and p-acetamidobenzoylglutamate (apABG).
Results: Detection limits were 0.07–0.52 nmol/L, and the assay was linear to 140 nmol/L for all analytes. The mean serum folate concentration from 168 blood donors was 22.7 nmol/L, of which 85.8% was 5mTHF, 12.1% hmTHF, 2.1% FA, and 0.0% 5fTHF. In the same individuals, the mean concentrations of pABG and apABG were 0.07 nmol/L and 0.47 nmol/L, respectively. The concentrations of folate catabolites were 22–30 times higher in 39 patients with renal failure. This folate assay correlated well with the microbiologic assay (r2 = 0.92) and with measurement of serum folate as pABG equivalents (r2 = 0.93).
Conclusions: This method based on liquid chromatography–tandem mass spectrometry measures the most abundant folate species and 2 folate catabolites in human serum. .
On the fate of early endosomes
Authors: Spang Anne 
Published: April 2009

Abstract
Proteins are endocytosed by various pathways into the cell. All these pathways converge at the level of the early endosome. The fate of the early endosome and how proteins are sorted into recycling and late endosomes/multi-vesicular body is a matter of debate and intense research. Obviously, the transition from early to late endosome poses an interesting logistic problem and would merit attention on an intellectual level. Numerous diseases are also caused by defects in turning off/over signaling molecules or mis-sorting of proteins at the level of the early endosome. This brief review aims to discuss different molecular mechanisms whereby early-to-late endosome transition could be achieved.
Activation mechanisms of coagulation factor IX
Authors: Zögg Thomas , Brandstetter Hans 
Published: April 2009

Abstract
Blood haemostasis is accomplished by a complex network of coagulatory and fibrinolytic processes. These processes have to be delicately balanced, as clinically manifested by bleeding disorders, such as haemophilia A and B. These disorders are caused by defects in coagulation factor VIII and factor IX, respectively. Following a dual strategy, we emphasise on the one hand principles conserved in most coagulation enzymes, thus mirroring much of the underlying complexity in haemostasis; on the other hand, we identify enzymatic properties of the factor IXa-factor VIIIa system (Xase) that distinguish this proteolytic machine from other components of the coagulation system. While the exact mechanisms of its activity modulation remain baffling until today, superactive factor IX mutants significantly improve our current understanding and serve as a specific and testable model of Xase action.
Beyond glycosylation: sialic acid precursors act as signaling molecules and are involved in cellular control of differentiation of PC12 cells
Authors: Kontou Maria , Weidemann Wenke , Bork Kaya , Horstkorte Rüdiger 
Published: April 2009

Abstract
Sialic acids represent a family of 9-carbon acidic amino sugars expressed mainly as terminal monosaccharides on most mammalian glycoconjugates. Sialic acids play an outstanding role during cellular processes, such as development and regeneration, as they are involved in a variety of molecular interactions. Sialic acids are synthesized in the cytosol starting from UDP-N-acetylglucosamine by the UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine-kinase (GNE), which is the key enzyme in the biosynthesis of sialic acid that catalyzes the generation of N-acetylmannosamine, which in turn is an intermediate of the sialic acid pathway that represents the natural molecular precursor of all sialic acids. Of increasing interest are the influence of the sialic acid precursor N-acetylmannosamine (or related N-acylmannosamines), GNE, and sialic acids themselves on cellular processes such as proliferation, gene expression, or cell differentiation. Here, we present recent data and review indications that N-acylmannosamines (the direct precursors of all sialic acids) may act as signaling molecules, and that the key enzyme of the sialic acid metabolism is directly involved in the regulation of cell proliferation and cell differentiation.
Krüppel-like factor 4 represses transcription of the survivin gene in esophageal cancer cell lines
Authors: Zhang Guo , Zhu Hongxia , Wang Yihua , Yang Shangbin , Liu Mei , Zhang Wei , Quan Lanping , Bai Jinfeng , Liu Zhihua , Xu Ningzhi 
Published: April 2009

Abstract
Aberrant expression of survivin has been shown to be regulated at the transcription level in cancer cells. In this study, we demonstrate that there are six putative binding sites of Krüppel-like factor 4 (KLF4) within the 2000-bp region upstream of the transcription start site of the human survivin gene. Luciferase reporter gene assays revealed that survivin promoter activity is repressed upon overexpression of KLF4 in EC9706 cells. A chromatin immunoprecipitation assay indicated that KLF4 indeed binds the survivin promoter in vivo. It specifically binds the site located at position -40 among the six binding sites as determined by electrophoretic mobility shift assay. Ectopic expression of KLF4 decreases the mRNA and protein levels of survivin. Furthermore, overexpression of survivin partially reverses KLF4-induced cell apoptosis. These results indicate that KLF4 is a transcriptional repressor of the human survivin gene in esophageal squamous cancer cells.
Identification of parasite-responsive cysteine proteases inManduca sexta
Authors: Serbielle Céline , Moreau Sébastien , Veillard Florian , Voldoire Emilien , Bézier Annie , Mannucci Marie-Anne , Volkoff Anne-Nathalie , Drezen Jean-Michel , Lalmanach Gilles , Huguet Elisabeth 
Published: April 2009

AbstractParasites have evolved different virulence strategies to manipulate host physiological functions. The parasitoid waspCotesia congregatainduces developmental arrest and immune suppression of its Lepidopteran hostManduca sexta. In this interaction, a symbiotic virus (C. congregataBracovirus, CcBV) associated with the wasp is essential for parasitism success. The virus is injected into the host with wasp eggs and virus genes are expressed in host tissues. Among potential CcBV virulence genes, cystatins, which are tight binding inhibitors of C1A cysteine proteases, are suspected to play an important role in the interaction owing to their high level of expression. So far, however, potentialin vivotargets inM. sextaare unknown. Here, we characterized for the first time fourM. sextaC1A cysteine proteases corresponding to cathepsin L and cathepsin B and two different ‘26–29 kDa’ cysteine proteases (MsCath1 and MsCath2). Our analyses revealed that MsCath1 and MsCath2 are transcriptionally downregulated in the course of parasitism. Moreover, viral Cystatin1 and MsCath1 co-localize in the plasma following parasitism, strongly suggesting that they interact. We also show that parasitism induces a general increase of cysteine protease activity which is later controlled. The potential involvement of cysteine proteases in defense against parasitoids is discussed.
Identification and characterization of a bioactive lantibiotic produced by Staphylococcus warneri
Authors: Petersen Jørgen , Boysen Anders , Fogh Lotte , Tabermann Kathrine , Kofoed Thomas , King Angus , Schrotz-King Petra , Hansen Martin Christian 
Published: April 2009

Abstract
Lantibiotics are a group of potent antibacterial agents that contain unusual amino acids, such as the thioether amino acids lanthionine and methyllanthionine, and the didehydroamino acids didehydroalanine and didehydro-aminobutyric acid. Here, we report on an antibacterial lantibiotic peptide named SWLP1 (Staphylococcus warneri lantibiotic peptide 1), which is secreted from Staphylococcus warneri (deposited with DSMZ, accession number DSM 16081). SWLP1 was purified from growth media. The purified peptide displays antibacterial activity against several species, including Staphylococcus epidermidis. The molecular mass of SWLP1 is 2998.9 Da as determined by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The sequence and possible structure was elucidated by combining electrospray ionization mass spectrometry/mass spectrometry data of ethanethiol-treated and non-ethanethiol-treated tryptic fragments of the SWLP1. SWLP1 contains three thioether bridges, one didehydroalanine, and three didehydroaminobutyric acids. This peptide has the potential to be used in treatment of several Gram-positive bacterial infections.