bluuebunny/crossref_metadata_2025_split huggingface dataset:
Xenopus Wnt11b is identified as a potential pronephric inducer
Authors: Tételin Stéphanie , Jones Elizabeth A. 
Published: July 2009

AbstractIn this study, we aimed to establish if known wnt signaling molecules could be responsible for inducing early pronephros specification, using a novel and effective in vitro bioassay in Xenopus embryos. Anterior somites have the unique biological activity to signal to unspecified intermediate mesoderm to induce pronephros formation in Xenopus embryos. We have used a molecular candidate gene approach to analyze both canonical and noncanonical wnt expression in isolated anterior and posterior somites and dissected presumptive pronephros, pronephric anlagen, and pronephros from stage 12.5–35 embryos. We have identified potential candidate wnt genes expressed in the right time and place to specify pronephric development. These candidates were then directly tested in an in vitro pronephrogenesis assay based on Holtfreter sandwich cultures. Results revealed that noncanonical wnt11b and wnt11 can induce pronephros formation in vitro. Loss‐of‐function experiments confirmed that these genes are necessary for normal pronephros development. Developmental Dynamics 239:148–159, 2010. © 2009 Wiley‐Liss, Inc.
Efficiency of a modified backwater wetland in trapping a pesticide mixture
Authors: Lizotte Richard E. , Shields F. Douglas , Knight Scott S. , Bryant Charles T. 
Published: July 2009

AbstractThe pesticide trapping efficiency of a modified backwater wetland amended with a mixture of three pesticides, atrazine, S‐metolachlor, and fipronil, using a simulated runoff event, was examined. The 700‐m long, 25‐m wide wetland, located along the Coldwater River in Tunica County, Mississippi, USA, was modified for hydrologic control via weirs at both ends. A pesticide mixture was amended into the wetland at the upstream weir simulating a 1‐h, 1·27‐cm‐rainfall event from a 16 ha agricultural field. Water samples (1 l) were collected hourly within the first 24 h and again on days 2, 5, 7, 15, 21, 28 and 56, post‐injection at both ends of the wetland for pesticide analysis. Peak pesticide concentrations were observed upstream 1 h after injection. Rapid pesticide removal from upstream water occurred with 63, 51 and 61% decrease of atrazine, S‐metolachlor and fipronil, respectively, by 24 h. By day 7, 79, 80 and 87% decreases from peak concentrations occurred. After day 28, all pesticide concentrations were < 0·3 µg l−1, and after day 56, no target pesticides were detected. Downstream, atrazine occurred in trace amounts (<0·4 µg l−1) within 24 h and after day 28 was not detectable. S‐Metolachlor occurred once downstream on day 21 (0·249 µg l−1), and fipronil was detected on days 15–56 in trace amounts (<0·05 µg l−1). Results indicate that modified backwater wetlands can efficiently trap pesticides in runoff from agricultural fields during small to moderate rainfall events, mitigating impacts to receiving waters in the main river channel. Published in 2009 by John Wiley & Sons, Ltd.
Mycobacterium chelonae sensitisation induces CD4+‐mediated cytotoxicity against BCG
Authors: Ho Peiying , Zhang Lin , Wei Xing , Seah Geok Teng 
Published: July 2009

AbstractSignificant variability in efficacy of live Mycobacterium bovis BCG as a tuberculosis vaccine is observed globally. Effects of pre‐vaccination sensitisation to non‐tuberculous environmental mycobacteria (Env) are suspected to underlie this phenomenon, but the mechanisms remain unclear. We postulated that it could be due to Env‐specific T cells exerting cytotoxicity against BCG‐infected host cells. After murine sensitisation with heat‐killed antigens of different Env species, splenocytes from M. chelonae (CHE)‐sensitised mice exerted the strongest cytotoxicity against autologous BCG‐infected macrophages. This cytotoxicity was correlated with reduced BCG viability. The cytotoxicity was reduced by the depletion of CD4+, but not CD8+ or CD56+ cells, and CD4+ cells showed higher percentage of cytotoxicity than CD4− cells, supporting a role for CD4+ cells in CHE‐induced, BCG‐specific cytotoxicity. Additionally, this cytotoxicity was IFN‐γ, perforin and FasL dependent. After CHE‐sensitisation and subsequent BCG intranasal infection, there was significant expansion of lung CD4+ cells, the main cell type producing IFN‐γ. This was associated with 2‐ and 6‐fold reductions in lung BCG counts 1 and 3 wk, respectively post‐ infection, relative to non‐sensitised mice. This is the first report describing cytotoxicity against BCG‐infected cells as a mechanism underlying the influence of Env sensitisation on subsequent BCG responses.
Mechanisms determining cell membrane expression of different γδ TCR chain pairings
Authors: Boucontet Laurent , Grana Martin , Alzari Pedro M. , Pereira Pablo 
Published: July 2009

AbstractWe investigated the ability of the most common TCR‐γ and δ chains to express on the cell surface. Vγ1Cγ4 and Vγ7Cγ1 chains paired with all TCR‐δ chains tested, whereas Vγ4Cγ1 chains were found with Vδ4 and Vδ5, but not with Vδ2 or Vδ6 chains, and Vγ2Cγ2 chains were expressed only with Vδ5. Mapping studies showed that up to four polymorphic residues influence the different co‐expressions of Vγ1 and Vγ2 chains with Vδ chains. Unexpectedly, these residues are not located in the canonical γ/δ interface, but in the outer part of the γδ TCR complex exposed to the solvent. Expression of functional Vδ4 or Vδ6 chains in Vγ2/Vδ5+ cells or of functional Vγ2Cγ2 in Vγ1+ cells reduced cell‐surface expression of the γδ TCR. Taken together, these data show that (i) the Vγ/Vδ repertoire of mouse γδ T cells is reduced by physical constraints in their associations. (ii) Lack of Vγ2/Vδ expression is due to the formation of aberrant TCR complexes, rather than to an intrinsic inability of the chains to pair and (iii) despite not being expressed at the cell surface, the presence of a functionally rearranged Vγ2 chain in γδ T cells results in reduced TCR levels.
A roadmap for thymic epithelial cell development
Authors: Anderson Graham , Jenkinson Eric J. , Rodewald Hans‐Reimer 
Published: July 2009

AbstractThymic epithelial cells (TEC) are essential components of the thymus that guide and control the development and TCR repertoire selection of T cells. Previously, TEC have been considered as postmitotic cells that, once generated during ontogeny, were maintained in their mature state. Recently, it has become clear that TEC can be generated from common or committed medullary and cortical TEC progenitor cells in ontogeny, that stages of immature and mature TEC are phenotypically separable, and that TEC undergo a rapid turnover in a matter of a few weeks. All of these findings strongly suggest that in the adult thymus mature TEC are constantly regenerated from a pool of stem or progenitor cells, a view that renders the thymus structure potentially much more dynamic than previously thought. However, the identity of “thymus stem cells” is elusive, and developmental stages of TEC development are only beginning to be elucidated.
Variations of iridoid oleuropein in Italian olive varieties during growth and maturation
Authors: Ranalli Alfonso , Marchegiani Donato , Contento Stefania , Girardi Fabio , Nicolosi Maria Paola , Brullo Marco Desiderio 
Published: July 2009

AbstractThis research paper reports on the concentrations of oleuropein in fruits of seven Italian olive cultivars. These oleuropein levels, during fruit growth and maturation, were monitored by taking olive samples from the same olive trees grown in Middle Italy. A novel high‐resolution gas chromatography (HRGC) oleuropein quantification method and a new high‐performance liquid chromatography (HPLC) method were developed. The olive fruits showed high contents of oleuropein, which were greatly influenced by the olive cultivar (genetic store) factor. The stage of fruit growth and maturation was another factor strongly affecting the contents of iridoid oleuropein in olive drupes, whatever the olive cultivar considered. Green olives had much higher concentrations of this biofunctional glucoside, which decreased regularly during fruit growth and ripeness. No differences were observed between the two developed oleuropein quantification methods, which gave, for all the olive cultivars, average values of fruit oleuropein contents that were not statistically different. These two reliable repetitive methods, noticeably the HPLC one (which also showed a lower running time), could be used for routine determination of oleuropein in olive drupes. We observed that, in general, olive cultivars having high oleuropein concentrations in the fruits were also characterized by marked oleuropein contents in the leaves.
Preparation of W1/O/W2 emulsions and droplet size distribution measurements by pulsed‐field gradient nuclear magnetic resonance (PFG‐NMR) technique
Authors: Wolf Frederik , Hecht Lena , Schuchmann Heike P. , Hardy Edme H. , Guthausen Gisela 
Published: July 2009

AbstractMultiple emulsions of W1/O/W2 type are of major interest in life sciences, offering possibilities for the encapsulation of water‐soluble active agents. In food science, they are also applied for fat reduction. The droplet size distributions of the inner and outer emulsions are of main importance as they influence the rheological and sensorial properties, the release kinetics, as well as the structural and microbial stability. However, the determination of the inner and outer droplet size distributions is a major challenge, as conventional measurement techniques cannot be applied. Pulsed‐field gradient nuclear magnetic resonance (PFG‐NMR) is well known as a non‐destructive tool for droplet size determination, especially in simple emulsions. In this work, double emulsions of the W1/O/W2 type were prepared with polyglycerol‐polyricinoleate (PGPR) and polyoxyethylen‐20‐sorbitan monolaurate (Tween 20) as emulsifiers by means of rotor‐stator emulsification machines. PFG‐NMR was applied for measurements of the inner phase (W1) droplet size distribution as well as for the characterization of the O phase. The W1 values were compared with results from laser light diffraction of simple emulsions (W1/O type) and were found to be consistent within the experimental errors, if restricted diffusion in the outer water phase (W2) and additional effects are considered.
Use of BPX‐70 60‐m GC columns for screening the fatty acid composition of industrial cookies
Authors: Vingering Nathalie , Ledoux Martial 
Published: July 2009

AbstractThe fatty acid (FA) composition of food is requested for labelling purposes and food composition tables. Suitable analytical methods for labelling purposes must be able to efficiently identify and accurately quantify FA as swiftly and cheaply as possible. This study evaluated a middle‐length highly polar column, the BPX‐70 60‐m column, to balance analysis efficiency and duration. The use of a 60‐m column led to the loss of data on minor FA but a gain in analysis time. The column was evaluated by analysing the FA composition of ten cookies made with different kinds of fats, including milk fat, and pure and/or partially hydrogenated vegetable oils. The FA elution order in this GC phase has been poorly documented in the literature compared to equivalent highly polar CPSil‐88 and SP‐2460 GC phases. Co‐elutions and overlaps on the BPX‐70 column were studied and commented upon. Overall, the BPX‐70 60‐m column could be used for rapid screening of the FA composition of simple foods. Analysis of the FA composition of a complex matrix, such as a dairy product, and specific analysis of trans‐FA required a longer highly polar column, possibly after fractionation by silver‐ion liquid chromatography. Compared to other GC phases, the BPX‐70 enabled effective isolation of 18:3 isomers although these isomers co‐eluted with 20:1 isomers on other highly polar GC phases. However, some CLA isomers co‐eluted with other FA on this column, and a specific analysis of these special FA would require another phase and/or different chromatographic conditions.
Introduction of Allyl and Prenyl Side‐Chains into Aromatic Systems by Suzuki Cross‐Coupling Reactions
Authors: Gerbino Darío C. , Mandolesi Sandra D. , Schmalz Hans‐Günther , Podestá Julio C. 
Published: July 2009

AbstractThis paper reports some studies aiming at the developement of a general protocol useful for the synthesis of allyl‐ and prenylaromatic compounds. The first part deals with the preparation of boron reagents like arylboronic acids and their pinacol esters as well as of pinacol allyl‐ and prenylboronates. The second part of the paper is devoted to the use of these boron reagents in Suzuki–Miyaura cross‐coupling reactions leading to allylation and prenylation of aromatic compounds. Of the six methods studied, the most promising results were obtained by using the Pd2(dba)3‐catalyzed reactions of arylboronic acids with allyl and prenyl bromides, that lead to the products of cross coupling in high yields (average 87%), and the reactions of aryl trifluoroborates with allyl and prenyl bromides catalyzed by Pd(OAc)2 that lead to the products of coupling in all cases in high yields (average 82%).(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
N‐Allylideneamines Derived from Acrolein: Synthesis and Use as Acceptors of Two Nucleophiles
Authors: Mizota Isao , Matsuda Yuri , Hachiya Iwao , Shimizu Makoto 
Published: July 2009

AbstractTwo practical methods have been developed for the preparation of N‐allylideneamines 1b,c. One involves the isomerization of propargylamines and the other the dehydration of acrolein. N‐Allylideneamines 1b,c thus prepared were used as efficient substrates for 1,4‐ and 1,2‐double nucleophilic addition reactions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Biased evaluation of information during discussion: Disentangling the effects of preference consistency, social validation, and ownership of information
Authors: Mojzisch Andreas , Grouneva Lilia , Schulz‐Hardt Stefan 
Published: July 2009

AbstractGroup members tend to be biased in their evaluation of the information discussed. The present study aimed to disentangle the effects of preference consistency, social validation, and ownership on information evaluation in a single experimental design. Participants first received information about a personnel selection task. After having made a decision, they read a transcript of a fictitious discussion. In the transcript, preference consistency, social validation, and ownership of information were orthogonally manipulated as within‐subjects factors. As hypothesized, preference consistency, social validation, and ownership all increased the perceived quality of information. Furthermore, participants intended to discuss a larger proportion of their preference‐consistent information than of their preference‐inconsistent information. This discussion bias was significantly associated with the evaluation bias favoring preference‐consistent information. These results provide the first empirical demonstration that the evaluation of information in groups is characterized by three distinct biases and that biased evaluation of information may contribute to biased discussion of information. Copyright © 2009 John Wiley & Sons, Ltd.
Influence of Analyte Flow Rate on Signal and Response Time of the Amperometric Gas Sensor with Nafion Membrane
Authors: Gębicki J. , Chachulski B. 
Published: July 2009

AbstractThis paper presents results of an investigation on influence of volumetric flow rate on the signal and response time of a prototype of sulfur dioxide gas sensor with Nafion membrane. The sensors differing in type of working electrode and composition of internal electrolyte were compared. We used Au and Pt working electrodes obtained via vacuum sublimation deposition on a Nafion membrane surface. The electrolytes were aqueous solutions of sulfuric acid of the summary concentration 5 mol dm−3 (electrolyte A). The electrolyte B contained an addition of dimethylsulfoxide (DMSO); the water/DMSO molar ratio was 2 : 1. Based on a proposed equation, which takes diffusion resistance into account, the obtained sensor signals were analyzed for the flow rate within a range of 0–100 cm3 min−1. The sensor response time was also determined for the above flow rate range.
Silicomolybdate‐Incorporated‐Glutaraldehyde‐Cross‐Linked Poly‐L‐Lysine Film Modified Glassy Carbon Electrode as Amperometric Sensor for Bromate Determination
Authors: Thangamuthu R. , Wu Yu‐Ching , Chen Shen‐Ming 
Published: July 2009

AbstractSilicomolybdate‐doped‐glutaraldehyde‐cross‐linked poly‐L‐lysine (PLL‐GA‐SiMo) film modified glassy carbon electrode was successfully prepared by means of electrostatically trapping the silicomolybdate anion in PLL‐GA cationic coating. The PLL‐GA‐SiMo film was stable and the charge transport through the film was fast. The modified electrode shows excellent electrocatalytic activity towards bromate reduction with significant reduction of overpotential. In amperometric determination of bromate, the calibration plot was linear over the concentration range of 5×10−5 to 1.2×10−3 M with a sensitivity of 3.6 μA mM−1. Furthermore, PLL‐GA‐SiMo film electrode showed fast response and good stability.
Characterization and identification of proteases secreted by Aspergillus fumigatus using free flow electrophoresis and MS
Authors: Neustadt Madlen , Costina Victor , Kupfahl Claudio , Buchheidt Dieter , Eckerskorn Christoph , Neumaier Michael , Findeisen Peter 
Published: July 2009

AbstractEarly diagnosis of life‐threatening invasive aspergillosis in neutropenic patients remains challenging because current laboratory methods have limited diagnostic sensitivity and/or specificity. Aspergillus species are known to secrete various pathogenetically relevant proteases and the monitoring of their protease activity in serum specimens might serve as a new diagnostic approach.For the characterization and identification of secreted proteases, the culture supernatant of Aspergillus fumigatus was fractionated using free flow electrophoresis (Becton Dickinson). Protease activity of separated fractions was measured using fluorescently labeled reporter peptides. Fractions were also co‐incubated in parallel with various protease inhibitors that specifically inhibit a distinct class of proteases e.g. metallo‐ or cystein‐proteases. Those fractions with high protease activity were further subjected to LC‐MS/MS analysis for protease identification. The highest protease activity was measured in fractions with an acidic pH range. The results of the ‘inhibitor‐panel’ gave a clear indication that it is mainly metallo‐ and serine‐proteases that are involved in the degradation of reporter peptides. Furthermore, several proteases were identified that facilitate the optimization of reporter peptides for functional protease profiling as a diagnostic tool for invasive aspergillosis.
Size‐based protein separations by microchip electrophoresis using an acid‐labile surfactant as a replacement for SDS
Authors: Root Brian E. , Zhang Bin , Barron Annelise E. 
Published: July 2009

AbstractWe demonstrate the use of an acid‐labile surfactant (ALS) as a replacement for SDS for size‐based protein separations in a microfluidic device. ALS is of interest to the proteomic field as it degrades at low pH and hence can be removed to reduce surfactant interference with down‐stream MS. A range of SDS and ALS concentrations were tested as denaturants for microchip electrophoresis to investigate their effects on the separation of proteins from 18 to 116 kDa and to provide a suitable comparison between the two surfactants. The electrophoretic mobilities of the proteins were not significantly affected by the use of ALS instead of SDS. Protein separations with ALS are performed in less than 3 min, which is a significant decrease in the time compared with the previous ALS separations on a slab gel format. We also demonstrate the use of poly‐N‐hydroxyethylacrylamide as a dynamic, hydrophilic chip channel coating that can be applied with a rapid and simple protocol for size‐based protein separation. The results reported here could significantly decrease the time and increase the attainable level of automation and integration of the front‐end protein fractionation required for “top‐down” proteomics.
The identification of phosphoglycerate kinase‐1 and histone H4 autoantibodies in pancreatic cancer patient serum using a natural protein microarray
Authors: Patwa Tasneem H. , Li Chen , Poisson Laila M. , Kim Hye‐Yeung , Pal Manoj , Ghosh Debashis , Simeone Diane M. , Lubman David M. 
Published: July 2009

AbstractProtein microarrays have been used to explore whether a humoral response to pancreatic cancer‐specific tumor antigens has utility as a biomarker of pancreatic cancer. To determine if such arrays can be used to identify novel autoantibodies in the sera from pancreatic cancer patients, proteins from a pancreatic adenocarcinoma cell line (MIAPACA) were resolved by 2‐D liquid‐based separations, and then arrayed on nitrocellulose slides. The slides were probed with serum from a set of patients diagnosed with pancreatic cancer and compared with age‐ and sex‐matched normal subjects. To account for patient‐to‐patient variability, we used a rank‐based non‐parametric statistical testing approach in which proteins eliciting significant differences in the humoral response in cancer compared with control samples were identified. The prediction analysis for microarrays classification algorithm was used to explore the classification power of the proteins found to be differentially expressed in cancer and control sera. The generalization error of the classification analysis was estimated using leave‐one‐out cross‐validation. A serum diagnosis of pancreatic cancer in this set was predicted with 86.7% accuracy, with a sensitivity and specificity of 93.3 and 80%, respectively. Candidate autoantibody biomarkers identified using this approach were studied for their classification power by performing a humoral response experiment on recombinant proteins using an independent sample set of 238 serum samples. Phosphoglycerate kinase‐1 and histone H4 were noted to elicit a significant differential humoral response in cancer sera compared with age‐ and sex‐matched sera from normal patients and patients with chronic pancreatitis and diabetes. This work demonstrates the use of natural protein arrays to study the humoral response as a means to search for the potential markers of cancer in serum.
Mimicking virus attachment to host cells employing liposomes: Analysis by chip electrophoresis
Authors: Weiss Victor U. , Bilek Gerhard , Pickl‐Herk Angela , Blaas Dieter , Kenndler Ernst 
Published: July 2009

AbstractElectrophoresis on a chip increasingly replaces electrophoresis in the capillary format because of its speed and containment of the sample within a disposable cartridge. In this paper we demonstrate its utility in the analysis of the interaction between a virus and a liposome‐anchored receptor, mimicking viral attachment to host cells. This became possible because detergents, obligatory constituents of the BGE for capillary electrophoretic separation of the virus, were not necessary in the chip format. Separations were carried out in sodium borate buffer, pH 8.3. Liposomes and virus were both labeled for laser‐induced fluorescence detection at λex/λem 630/680 nm. Free virus and virus‐receptor complexes were resolved from virus attached to receptor‐decorated liposomes in the absence of additives or sieving matrices within about 30 s on commercially available microfluidic chips.