bluuebunny/crossref_metadata_2025_split huggingface dataset:
Whole‐mount identification of gene transcripts in aphids: Protocols and evaluation of probe accessibility
Authors: Chang Chun‐che , Huang Ting‐Yu , Shih Chun‐Liang , Lin Gee‐Way , Chang Te‐Pin , Chiu Hui , Chang Wen‐Chang 
Published: May 2008

AbstractIn situ hybridization has become a powerful tool for detecting the temporal and spatial distribution of gene transcripts in prokaryotes and eukaryotes. We report an efficient protocol for whole‐mount identification of the expression of mRNAs in the parthenogenetic pea aphidAcyrthosiphon pisum, an emerging model organism with a growing accumulation of genome sequencing data. In addition to steps common for most animal in situ hybridization protocols, we describe processing methods specific to aphids, the accessibility of antisense riboprobes of different lengths in whole‐mounted aphids, and signal intensity versus probe lengths. To find substrate combinations that clearly contrast single and double in situ signals inA. pisum, we tested our protocols using riboprobes constructed from two conserved germline markers,ApvasaandApnanos, and examined colocalized signals in the germaria and developing oocytes. Finally, we propose conditions for stringent permeabilization that may be applied to tissues deep within the aphid embryo. Arch. Insect Biochem. Physiol. 2008. © 2008 Wiley‐Liss, Inc.
Angiotensin‐converting enzyme‐like activity in crab gills and its putative role in degradation of crustacean hyperglycemic hormone
Authors: Chung J. Sook , Webster S.G. 
Published: May 2008

AbstractAngiotensin‐converting enzyme‐like enzyme activity (ACELA) was found in Carcinus maenas using reverse phase high performance liquid chromatography (RP‐HPLC) analysis of degradation kinetics of a synthetic substrate (Hippuryl‐histidyl‐leucine) and a specific inhibitor (captopril). Gills contained the highest ACELA, then brain, muscle, and testis, respectively, while no activity was detected in the following tissues: hepatopancreas, hindgut, hypodermis, heart, and hemolymph. ACELA present in gill membranes exhibited a Km of 0.23 mM and Vmax of 7.6 nmol with synthetic substrate. The enzyme activity was dependent on Cl– concentration and was markedly inhibited by captopril, lisinopril, and EDTA. Addition of Zn2+ to membranes previously treated with EDTA restored 89% activity, suggesting that C. maenas ACELA is a Zn2+ metalloenzyme. Gill membranes prepared from premolt crabs showed similar levels of ACELA to those of the intermolt animals. Administration of captopril in vivo lengthened the half life of circulating CHH, while in vitro incubation of gill membranes with captopril reduced CHH. These results suggest that C. maenas ACELA present in gills is likely to be involved in degradation of this neuropeptide. Arch. Insect Biochem. Physiol. 2008. © 2008 Wiley‐Liss, Inc..
Bayesian approach for g‐mode detection, or how to restrict our imagination
Authors: Appourchaux T. 
Published: May 2008

AbstractNowadays, g‐mode detection is based upon a priori theoretical knowledge. By doing so, detection becomes more restricted to what we can imagine. De facto, the universe of possibilities ismade narrower. Such an approach is pertinent for Bayesian statisticians. Examples of how Bayesian inferences can be applied to spectral analysis and helioseismic power spectra are given. Our intention is not to give the full statistical framework (much too ambitious) but to provide an appetizer for going further in the direction of a proper Bayesian inference, especially for detecting gravity modes. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
p‐mode power variation with solar atmosphere as observed in the Na D1 and K spectral lines
Authors: Simoniello R. , Jiménez‐Reyes S.J. , García R.A. , Pallé P.L. 
Published: May 2008

AbstractIn this work we investigate p‐mode power variation with solar atmosphere. To this aim, we use THÉMIS observations of the Na D1 (λ 5896 Å) and K (λ 7699 Å) spectral lines. While the formation heights of the K spectral line are essentially located in the photospheric layer, the formation heights of the Na D1 line span a much wider region: from photosphere up to chromosphere. Hence, we had the opportunity to infer p‐mode power variation up to the chromospheric layer. By analyzing power spectra obtained by temporal series at different points of the Na D1 and K spectral lines, we confirm and quantify the increase in p‐mode power towards higher atmospheric layers. Furthermore, the large span in formation heights of the Na D1 line induces a larger enhancement of p‐mode power with solar atmosphere compared to the K spectral line. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modelling solar atmospheric gravity oscillation modes
Authors: Pintér B. 
Published: May 2008

AbstractSolar oscillations are investigated in a one‐dimensional hydrodynamic plane‐parallel model with an atmosphere. Besides the acoustic pressure (p) modes, the fundamental (f) and Lamb mode, another set of eigenmodes, a group of atmospheric gravity (g) modes, is found in the low‐frequency region of the spectrum. Their frequencies and spatial behaviour are studied. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Gravity modes and mixed modes as probes of stellar cores in main‐sequence stars: From solar‐like to β Cep stars
Authors: Miglio A. , Montalbán J. , Eggenberger P. , Noels A. 
Published: May 2008

AbstractWe investigate how the frequencies of gravity modes depend on the detailed properties of the chemical composition gradient that develops near the core of main‐sequence stars and, therefore, on the transport processes that are able to modify the μ profile in the central regions. We show that in main‐sequence models, similarly to the case of white dwarfs, the periods of high‐order gravity modes are accurately described by a uniform period spacing superposed to an oscillatory component. The periodicity and amplitude of such a component are related, respectively, to the location and sharpness of the μ gradient. We briefly discuss and interpret, by means of this simple approximation, the effect of turbulent mixing near the core on the periods of both high‐order and low‐order g modes, as well as of modes of mixed pressure‐gravity character. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Initial results of primary device closure of large muscular ventricular septal defects in early infancy using perventricular access
Authors: Crossland D.S. , Wilkinson J.L. , Cochrane A.D. , d'Udekem Y. , Brizard C.P. , Lane G.K. 
Published: May 2008

AbstractObjectives: To report our experience with the use of the Amplatzer muscular ventricular septal defect (VSD) occluder, using direct right ventricle free wall puncture for primary closure of muscular VSDs in infants. Background: Young infants with heart failure due to large or multiple muscular VSDs often require intervention at a stage when percutaneous device closure is impractical due to delivery system limitations. There are considerable benefits to avoiding bypass in these infants. Methods: Patients with suitable muscular VSDs, considered too small for transvenous closure, underwent perventricular muscular VSD closure under transesophageal echo (TEE) guidance. Results: Eight infants underwent the procedure. The median age was 14 weeks (2–41) with median weight of 4 kg (3–6.6). Four patients had additional VSDs and one patient had previous repair of coarctation. One patient had dextrocardia and severe left ventricular impairment due to an associated cardiomyopathy. The median VSD size was 8 mm (range, 4–10 mm). A single device (6–12 mm) was deployed in each patient, the size chosen being 1–2 mm larger than the TEE measurement. Two patients had subsequent pulmonary artery banding, with absorbable bands, because of moderate residual shunting through additional VSDs. The latest echo study at a median of 7.2 weeks (0.5–66) post device implantation revealed no patients with a hemodynamically significant shunt. Conclusion: Perventricular muscular VSD closure can be safely and effectively undertaken in small infants with suitable muscular defects, and this strategy can avoid the need for bypass. © 2008 Wiley‐Liss, Inc.
Dynamic contrast‐enhanced MRI diagnostics in oncology via principal component analysis
Authors: Bruwer Mark‐John , MacGregor John F. , Noseworthy Michael D. 
Published: May 2008

AbstractThis paper proposes the use of latent variable models based on principal component analysis (PCA) as a robust alternative to pharmacokinetic modeling for the analysis of the dynamic contrast‐enhanced magnetic resonance images (DCE‐MRI) often obtained during oncological studies. Theoretical and practical justifications are provided for the advantages of the PCA approach. A pilot study using clinical DCE‐MRI data on prostate patients is presented to demonstrate the method. Copyright © 2008 John Wiley & Sons, Ltd.
A Novel Linker Methodology for the Synthesis of Tailored Conjugate Vaccines Composed of Complex Carbohydrate Antigens and Specific TH‐Cell Peptide Epitopes
Authors: Dziadek Sebastian , Jacques Sandra , Bundle David R. 
Published: May 2008

AbstractPathogenic organisms or oncogenically transformed cells often express complex carbohydrate structures at their cell surface, which are viable targets for active immunotherapy. We describe here a novel, immunologically neutral, linker methodology for the efficient preparation of highly defined vaccine conjugates that combine complex saccharide antigens with specific TH‐cell peptide epitopes. This novel heterobifunctional approach was employed for the conjugation of a (1→2)‐β‐mannan trisaccharide from the pathogenic fungus Candida albicans as well as the carbohydrate portion of tumor‐associated ganglioside GM2 to a TH‐cell peptide epitope derived from the murine 60 kDa self heat‐shock protein (hsp60). Moreover, the linkage chemistry has proven well suited for the synthesis of more complex target structures such as a biotinylated glycopeptide, a three component vaccine containing an immunostimulatory peptide epitope from interleukin‐1β (IL‐1β), and for the conjugation of complex carbohydrates to carrier proteins such as bovine serum albumin.
A DFT Study of the Mechanism of Polymerization of ε‐Caprolactone Initiated by Organolanthanide Borohydride Complexes
Authors: Barros Noémi , Mountford Philip , Guillaume Sophie M. , Maron Laurent 
Published: May 2008

AbstractThe mechanisms of polymerization of ε‐caprolactone (CL) initiated by either the rare‐earth hydride [Cp2Eu(H)] or the borohydrides [Cp2Eu(BH4)] or [(N2NN′)Eu(BH4)] were studied at the DFT level (Cp=η5‐C5H5; N2NN′=(2‐C5H4N)CH2(CH2‐ CH2NMe)2). For all compounds the reaction proceeds in two steps: a hydride transfer from the rare earth initiator to the carbonyl carbon of the lactone, followed by ring‐opening of the monomer. In the last step a difference is observed between the hydride and borohydride complexes, because for the latter the ring‐opening is induced by an additional BH bond cleavage leading to a terminal CH2OBH2 group. This corresponds to the reduction by BH3 of the carbonyl group of CL. Upon reaction of [Cp2Eu(H)] with CL, the alkoxy–aldehyde complex produced, [Cp2Eu{O(CH2)5C(O)H}], is the first‐formed initiating species. In contrast, for the reaction of CL with the borohydride complexes [(Lx)Eu(BH4)] (Lx=Cp2 or N2NN′), an aliphatic alkoxide with a terminal CH2OBH2 group, [(Lx)Eu{O(CH2)6OBH2}] is formed and subsequently propagates the polymerization. The present DFT investigations are fully compatible with previously reported mechanistic studies of experimental systems.
A PTD‐based transaction protocol for public transportation
Authors: Chen Chin‐Ling 
Published: May 2008

AbstractAdvances in wireless network technology and the increasing number of users of the personal trusted device (PTD) make the PTD an ideal channel for offering personalized services to mobile users. In this paper, we propose using a PTD as a payment tool in a mobile transaction system for public transportation. To overcome the inherent weakness of computing resources in a PTD, we use a trusted observer to coordinate the mobile transaction and to integrate cryptology (such as a digital signature and a one‐way hash function).The proposed scheme satisfies the requirements for mobile transactions. These requirements include fairness, non‐repudiation, anonymity, off‐line capability, no forgery, efficient verification, simplicity, and practicability. Because a PTD is more portable and personal than a personal computer and because the public transportation can be a necessity in our daily lives, our scheme proposes a novel use of PTDs in mobile commerce. Copyright © 2008 John Wiley & Sons, Ltd.
{2‐[1‐(2,6‐Diisopropylphenylimino)ethyl]pyridyl}palladium Dibromide Polymorphs Originating from Different Br···π and C–H···Br Contacts
Authors: Zhang Wenjuan , Tang Xiubo , Ma Hongwei , Sun Wen‐Hua , Janiak Christoph 
Published: May 2008

Abstract{2‐[1‐(2,6‐Diisopropylphenylimino)ethyl]pyridyl}palladiumdibromide (1) was synthesized and crystallized as red crystals from chloroform in the monoclinic space group P21/c or as yellow crystals from methanol in the triclinic space group P$\bar {1}$. Other solvents, such as THF and acetonitrile, gave mixtures of red and yellow crystals. With very little conformational differences between the molecules in the dimorphs of 1 the crystal packing is a herringbone array in 1‐red and a parallel array in 1‐yellow, with the supramolecular interactions differing in the Br···π and C–H···Br contacts. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Chlorpyrifos‐induced DNA damage in rat liver and brain
Authors: Mehta Anugya , Verma Radhey S. , Srivastava Nalini 
Published: May 2008

AbstractChlorpyrifos (O,O'‐diethyl‐O‐3,5,6‐trichloro‐2‐pyridyl phosphorothionate, CPF) is a broad spectrum organophosphate pesticide used to control a variety of pests. The present study was undertaken to test the in vivo genotoxic potential of CPF in rats, using the single cell gel electrophoresis (or comet) assay. The rats were administered 50 mg and 100 mg CPF/kg body weight daily for 1, 2, and 3 days as well as 1.12 mg and 2.24 mg CPF/kg body weight for 90 days. The level of DNA damage was estimated by scoring 100 cells per animal, dividing into five types: types 0, I, II, III, and IV. The results clearly indicate that exposure to CPF, acutely or chronically, caused a dose‐dependent increase in DNA damage in the liver and brain of rats. From the present study, it can be concluded that CPF exhibits genotoxic potential in vivo. Environ. Mol. Mutagen., 2008. © 2008 Wiley‐Liss, Inc.
Estrogen is a modulator of vascular inflammation
Authors: Chakrabarti Subhadeep , Lekontseva Olga , Davidge Sandra T 
Published: May 2008

AbstractVascular inflammation underlies the pathogenesis of atherosclerosis. Atherosclerotic changes in the vasculature lead to conditions such as coronary artery disease and stroke, which are the major causes of morbidity and mortality worldwide. Epidemiological studies in premenopausal women suggest a beneficial role for estrogen in preventing vascular inflammation and consequent atherosclerosis. However, the benefits of estrogen areabsent or even reversed in older postmenopausal subjects. The modulation of inflammation by estrogen under different conditions might explain this discrepancy. Estrogen exerts its antiinflammatory effects on the vasculature through different mechanisms such as direct antioxidant effect, generation of nitric oxide, prevention of apoptosis in vascular cells and suppression of cytokines and the renin‐angiotensin system. On the other hand, estrogen also elicits proinflammatory changes under certain conditions, which are less completely understood. Some of the mechanisms underlying a possible proinflammatory role for estrogen include increased expression of the proinflammatory receptor for advanced glycation end products, increased tyrosine nitration of cellular proteins, and generation of reactive oxygen species through an uncoupled eNOS. In this review, we have presented evidence for both antiinflammatory and proinflammatory pathways modulated by estrogen and how interactions among such pathways might determine the effects of estrogen on the vascular system. © 2008 IUBMB IUBMB Life, 60(6): 376–382, 2008
Endogenous ATP potentiates only vasopressin secretion from neurohypophysial terminals
Authors: Knott Thomas K. , Marrero Héctor G. , Custer Edward E. , Lemos José R. 
Published: May 2008

AbstractExogenous ATP induces inward currents and causes the release of arginine‐vasopressin (AVP) from isolated neurohypophysial terminals (NHT); both effects are inhibited by the P2X2 and P2X3 antagonists, suramin and PPADS. Here we examined the role of endogenous ATP in the neurohypophysis. Stimulation of NHT caused the release of both AVP and ATP. ATP induced a potentiation in the stimulated release of AVP, but not of oxytocin (OT), which was blocked by the presence of suramin. In loose‐patch clamp recordings, from intact neurohypophyses, suramin or PPADS produces an inhibition of action potential currents in a static bath, that can be mimicked by a hyperpolarization of the resting membrane potential (RMP). Correspondingly, in a static versus perfused bath there is a depolarization of the RMP of NHT, which was reduced by either suramin or PPADS. We measured an accumulation of ATP (3.7 ± 0.7 µM) released from NHT in a static bath. Applications of either suramin or PPADS to a static bath decreased burst‐stimulated capacitance increases in NHT. Finally, only vasopressin release from electrically stimulated intact neurohypophyses was reduced in the presence of Suramin or PPADS. These data suggest that there was sufficient accumulation of ATP released from the neurohypophysis during stimulations to depolarize its nerve terminals. This would occur via the opening of P2X2 and P2X3 receptors, inducing an influx of Ca2+. The subsequent elevation in [Ca2+]iwould further increase the stimulated release of only vasopressin from NHT terminals. Such purinergic feedback mechanisms could be physiologically important at most CNS synapses. J. Cell. Physiol. 217: 155–161, 2008. © 2008 Wiley‐Liss, Inc.
Stone run (block stream) formation in the Falkland Islands over several cold stages, deduced from cosmogenic isotope (10Be and 26Al) surface exposure dating
Authors: Wilson Peter , Bentley Michael J. , Schnabel Christoph , Clark Richard , Xu Sheng 
Published: May 2008

AbstractCosmogenic isotope (10Be and 26Al) surface exposure dating has been applied to valley‐axis and hillslope stone runs (relict periglacial block streams) and their source outcrops in the Falkland Islands, South Atlantic. The data indicate that stone runs are considerably older landforms than previously envisaged and afford no evidence that they are a product of the Last Glacial Maximum; the samples range in apparent 10Be age from 42k to 731k yr BP, but some of these are minima. The results indicate that valley‐axis stone runs may be up to 700–800k yr old, have simple exposure histories and are composite landforms that developed over several cold stages. Analyses of some hillslope and outcrop samples also demonstrate simple exposure histories with 10Be ages from 42k to 658k yr BP. In contrast, isotopic ratios from other hillslope and outcrop samples reveal they have had a complex exposure history involving periods of burial or shielding; the samples range in 10Be age from 59k to 569k yr BP and these are regarded as minimum age estimates. Larger stone runs may be older than smaller runs and there is a possibility that stone runs older than 800k yr exist in other parts of the Falklands. The assertion that glaciation in the Falklands was restricted to the highest uplands is supported by the data, and the potential for age determination of other boulder‐strewn and bedrock landforms, using cosmogenic isotope analysis, in order to extend the geochronology of Quaternary events and processes is noted. Copyright © 2008 John Wiley & Sons, Ltd.
A Cleavable Network Based on Crosslinked Star Polymers Containing Acid‐Labile Diacetal Crosslinks: Synthesis, Characterization and Hydrolysis
Authors: Themistou Efrosyni , Patrickios Costas S. 
Published: May 2008

AbstractA hydrolyzable model network comprising interconnected star polymers was prepared by the sequential group transfer polymerization of methyl methacrylate and the acid‐labile diacetal‐based dimethacrylate crosslinker bis[(2‐methacryloyloxy)ethoxymethyl] ether. In contrast to other polymer networks previously synthesized by our group, all the branching points of this polymer network were found to hydrolyze under mildly acidic conditions, giving a linear copolymer with the theoretically expected molecular weight and composition. The ease of hydrolysis of this polymer network renders it a good candidate for use in the biomedical field. The characterization of the synthesized network, its linear and star polymer precursors and the hydrolysis products of the network and its precursors, by a variety of techniques, established the successful synthesis and hydrolysis of this well‐defined polymer nanostructure.magnified image
Effects of Crosslinking Methods on Structure and Properties of Cellulose/PVA Hydrogels
Authors: Chang Chunyu , Lue Ang , Zhang Lina 
Published: May 2008

AbstractA series of hydrogels were prepared from cellulose and PVA in NaOH/urea aqueous solution using both physical and chemical crosslinking methods. The hydrogels were secure and biodegradable materials. Their structure and properties were characterized by FTIR spectroscopy, DSC, XRD and SEM. The results indicated that all of the cellulose/PVA hydrogels exhibited homogeneous porous structures and a certain miscibility. The swelling degree and water uptake of the chemical hydrogels were markedly higher than those of the physical hydrogel. This work demonstrates two novel methods to prepare cellulose/PVA hydrogels with different functional properties via a green process.magnified image
The ProteoMiner and the FortyNiners: Searching for gold nuggets in the proteomic arena
Authors: Righetti Pier Giorgio , Boschetti Egisto 
Published: May 2008

AbstractThe present review covers modern aspects of combinatorial peptide ligand libraries (CPLL), as used to analyze the “low‐abundance proteome” in association with mass spectrometry. First, the capturing properties of baits of different lengths (from single amino acid to hexa‐peptides) are described to show that a plateau is rapidly reached above a tetra‐peptide in length, thus confirming the validity of having adopted hexapeptides for the considered application. The mechanism of interaction with proteins from very complex proteomes and the ability to decrease the dynamic concentration range is demonstrated with the help of mass spectrometry analysis. Examples are given on how treatment with CPLLs dramatically improves the detectability of peptides in mass spectrometry analysis, permitting detection of a very large number of proteins as compared with control, untreated samples. The use of complementary libraries is discussed with the aim to discover additional low‐abundance species that escaped the first library. A discussion on the possibility to discover extremely rare gene products, and the quantitative aspect of the technology when associated with mass spectrometry is also provided. Some insights on the applications for hidden, low‐abundance biomarkers are also presented. © 2008 Wiley Periodicals, Inc., Mass Spec Rev 27: 596–608, 2008