bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cover Picture: Enhancement of Electrogenerated Chemiluminescence and Radical Stability by Peripheral Multidonors on Alkynylpyrene Derivatives (Angew. Chem. Int. Ed. 14/2009)
Authors: Oh Jeong‐Wook , Lee Yeon Ok , Kim Tae Hyun , Ko Kyoung Chul , Lee Jin Yong , Kim Hasuck , Kim Jong Seung 
Published: March 2009

AbstractA Powerful Luminophore that comprises a centered pyrene acceptor with peripheral amine multidonors is described by J. S. Kim and co‐workers in their Communication on page 2522 ff. The electrochemiluminescence (ECL) efficiency and radical stability of pyrene, a poor ECL luminophore, is markedly improved as the number of peripheral multidonor units is increased in a series of compounds. The ECL enhancement was rationalized by photophysical and electrochemical studies, and theoretical calculations.magnified image
Inside Cover: A Nanoscale Molecular Switch Triggered by Thermal, Light, and Guest Perturbation (Angew. Chem. Int. Ed. 14/2009)
Authors: Duriska Martin B. , Neville Suzanne M. , Moubaraki Boujemaa , Cashion John D. , Halder Gregory J. , Chapman Karena W. , Balde Chérif , Létard Jean‐François , Murray Keith S. , Kepert Cameron J. , Batten Stuart R. 
Published: March 2009

AbstractContinuous switching between high‐spin and low‐spin magnetic states can be accomplished by irradiation with red and green laser light, respectively. In their Communication on page 2549 ff., S. R. Batten and co‐workers report a metallo‐supramolecule that undergoes spin crossover (SCO) switching induced by temperature change or light irradiation. The SCO behavior is also dependent on the presence and nature of intercalated solvent molecules within the porous crystal structure.magnified image
Effects of 20‐hydroxyecdysone and juvenile hormone on octopamine metabolism in females of Drosophila
Authors: Bogomolova E. V. , Adonyeva N. V. , Gruntenko N. E. , Rauschenbach I. Yu. 
Published: March 2009

AbstractThe effect of exogenous 20‐hydroxyecdysone (20E) and juvenile hormone (JH) on the activities of the tyrosine decarboxylase (TDC), the first enzyme in octopamine (OA) synthesis, has been studied in young females of wild type D. virilis and D. melanogaster under normal and heat stress (38°C) conditions. Flies fed 20E expressed increased TDC activity in both species. JH application decreased TDC activity in both species. A rise in JH and 20E levels did not prevent a TDC response to heat stress, but changed the response intensity. A long‐term increase in JH titre had no effect on the activity of main OA catabolyzing enzyme, arylalkylamine N‐acetyltransferase, in females of both species. A possible mechanism of regulation of OA levels by 20E and JH in Drosophila females is discussed. © 2009 Wiley Periodicals, Inc.
Current Synthesis of Triterpene Saponins
Authors: Yu Biao , Sun Jiansong 
Published: March 2009

AbstractIt′s complicated! Triterpene saponins are a structurally and biologically diverse class of glycoconjugates of triterpenes that are widely distributed in terrestrial plants and some marine organisms. Current synthesis of these complex glycoconjugates has been discussed, whereupon the stereocontrolled glycosylation, global protection/deprotection, and the total synthesis of four unusual triterpene saponins are highlighted.magnified imageTriterpene saponins are a structurally and biologically diverse class of glycoconjugates of triterpenes that are widely distributed in terrestrial plants and some marine organisms. Current synthesis of these complex glycoconjugates has been discussed, whereupon the stereocontrolled glycosylation, global protection/deprotection, and the total synthesis of four unusual triterpene saponins are highlighted.
Catalytic resonance scattering spectral determination of ultratrace horseradish peroxidase using rhodamine S
Authors: Jiang Zhiliang , Liang Yueyuan , Huang Guoxia , Wei Xiaoling , Liang Aihui , Zhong Fuxin 
Published: March 2009

AbstractA highly sensitive and selective resonance scattering spectral assay was proposed for the determination of horseradish peroxidase (HRP), based on its catalytic effect on the H2O2 oxidation of KI to form I3−. The I3− combined respectively with rhodamine (Rh) dye such as rhodamine S (RhS), rhodamine 6G (Rh6G), rhodamine B (RhB) and butyl‐rhodamine B (b‐RhB), to form association particles (Rh‐I3)n. The four Rh systems all exhibit a stronger resonance scattering (RS) peak at 424 nm. For the RhS, Rh6G, RhB and b‐RhB systems, HRP concentration in the range of 3.2 × 10−12 to 4.8 × 10−9, 2 × 10−11 to 3.2 × 10−9, 1.6 × 10−11 to 3.2 × 10−9 and 1.6 × 10−11 to 4 × 10−9 g/mL was linear to its RS intensity at 424 nm, with a detection limit of 2.2 × 10−12, 2.5 × 10−12, 4.4 × 10−12 and 2.6 × 10−12 g/mL, respectively. This RhS system was most sensitive and stable, and was applied for the determination of HRP in the hepatitis B surface antibody labeling HRP and water samples, with satisfactory results. Copyright © 2009 John Wiley & Sons, Ltd.
A bioluminescent enzyme immunoassay for prostaglandin E2 using Cypridina luciferase
Authors: Wu Chun , Irie Saki , Yamamoto Shozo , Ohmiya Yoshihiro 
Published: March 2009

AbstractProstaglandin E2 is one of the major cyclooxygenase metabolites of arachidonic acid. We developed a competitive immunosorbent assay for prostaglandin E2 utilizing a bioluminescent enzyme Cypridina luciferase. The prostaglandin E2 amount could be quantified over the concentration ranging from 7.8 to 500 pg/mL. The amount of unlabeled prostaglandin E2 required to displace 50% of the maximal binding of Cypridina luciferase‐labeled prostaglandin E2 (B/B0) was approximately 35 pg/mL. The results show a great potential of Cypridina luciferase as a new labeling enzyme for enzyme‐linked immunosorbent assay. Copyright © 2009 John Wiley & Sons, Ltd.
Flow‐injection analysis for meloxicam based on tris(2,2′‐bipyridine) ruthenium(II)–Ce(IV) chemiluminescent system
Authors: Ye Huazhen , Qiu Bin , Chen Jing , Lin Jinming , Chen Guonan 
Published: March 2009

AbstractIt was found that meloxicam could enhance the chemiluminescence (CL) of the tris(2,2'‐bipyridine) ruthenium(II)–Ce(IV) system in the medium of sulfate acid. Based on this phenomenon a new flow‐injection system with chemiluminescent detection has been proposed for determination of meloxicam. Under optimum conditions, meloxicam had a good linear relationship with the CL intensity in the concentration range of 6.0 10−4 to 1.0 µg/mL and the detection limit was 3.7 × 10−4 µg/mL. The proposed method was applied to detect meloxicam in tablets and a satisfactory recovery was obtained. The possible mechanism for this CL system is also discussed in this paper. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis and Biological Characterisation of Novel N‐Alkyl‐Deoxynojirimycin α‐Glucosidase Inhibitors
Authors: Rawlings Amy J. , Lomas Hannah , Pilling Adam W. , Lee Marvin J.‐R. , Alonzi Dominic S. , Rountree J. S. Shane , Jenkinson Sarah F. , Fleet George W. J. , Dwek Raymond A. , Jones John H. , Butters Terry D. 
Published: March 2009

AbstractIlluminating glucosidases: The shown photoaffinity probe for endoplasmic reticulum (ER) α‐glucosidases was found to be a highly potent inhibitor of α‐glucosidase I in vitro and equally effective at inhibiting cellular ER glucosidases, as determined by a free oligosaccharide (FOS) analysis.magnified imageThe N‐alkylated deoxynojirimycin compound, N‐(6′‐(4′′‐azido‐2′′‐nitrophenylamino)hexyl)‐1‐deoxynojirimycin (6) was synthesised as a potential photoaffinity probe for endoplasmic reticulum (ER) α‐glucosidases I and II. Surprisingly this compound was a highly potent inhibitor of α‐glucosidase I (IC50, 17 nM) in an in vitro assay and proved equally effective at inhibiting cellular ER glucosidases, as determined by a free oligosaccharide (FOS) analysis. A modest library of compounds was synthesised to obtain structure–activity information by variation of the N‐alkyl chain length and modifications to the azido‐nitrophenyl group. All of these compounds failed to improve on the efficacy of compound 6, but most showed greater enzyme inhibitory potency than N‐butyl‐deoxynojirimycin (NB‐DNJ), a pharmacological agent that has been evaluated for the treatment of several viruses for which infectivity is dependent on host cell glycosylation.
Effects of downstream system on self‐excited oscillations in collapsible tubes
Authors: Wang J. W. , Chew Y. T. , Low H. T. 
Published: March 2009

AbstractDuring self‐excited oscillation, the effects of downstream head, resistance and inertia on the amplitude and frequency of the tube outlet pressure and flow have been studied experimentally. Different sets of resistance and head combinations could be arranged to achieve identical mean pressure–flow condition, but the unsteady pressure and flow waveforms were found to be different. In a conventional experimental set‐up, the direct effect of downstream resistance could be inadvertently complicated by the indirect ones, which were caused by the associated variations of mean pressure and flow on the downstream head. Copyright © 2009 John Wiley & Sons, Ltd.
Host‐Assisted Guest Self‐Assembly: Enhancement of the Dimerization of Pyronines Y and B by γ‐Cyclodextrin
Authors: Bordello Jorge , Reija Belén , Al‐Soufi Wajih , Novo Mercedes 
Published: March 2009

AbstractBuckle up! The dimerization of small fluorescent guests is strongly enhanced in presence of a cyclodextrin host. The host cavity acts like a belt to assist the self‐assembly of guests (see picture). Small variations in the guest structure have significant influence on the stability and geometry of the aggregates.magnified imageThe role of small variations in the structural properties of host and guest molecules on the stoichiometry and strength of supramolecular associations is analyzed. Earlier we found that a change in substituents from pyronine B to pyronine Y has a dramatic effect on both the stability and the dynamics of the association of these guests with β‐cyclodextrin as host. Now we study the association between these two pyronines and a cyclodextrin with a bigger cavity (γ‐cyclodextrin) using UV/Vis absorption and fluorescence spectroscopy. The absorption spectra of the pyronines show complex variations with cyclodextrin concentration indicating that pyronine dimerization is strongly enhanced inside the cavity of the cyclodextrin. A full model is proposed and the equilibrium constants of the involved processes and the absorption and emission spectra of the different species are estimated. The equilibrium constants of the formation of complexed dimers are much higher than those for free dimerization or for the inclusion of a single guest. The γ‐cyclodextrin host acts like a belt to assist the guest self‐assembly. The differences in the stability of pyronine B and pyronine Y dimers are explained on the basis of their structure and geometry.
Non‐Blinking Semiconductor Colloidal Quantum Dots for Biology, Optoelectronics and Quantum Optics
Authors: Spinicelli Piernicola , Mahler Benoit , Buil Stéphanie , Quélin Xavier , Dubertret Benoit , Hermier Jean‐Pierre 
Published: March 2009

AbstractTwinkle, twinkle: The blinking of semiconductor colloidal nanocrystals is the main inconvenience of these bright nanoemitters. There are various approaches for obtaining non‐blinking nanocrystals, one of which is to grow a thick coat of CdS on the CdSe core (see picture). Applications of this method in the fields of optoelectronic devices, biologic labelling and quantum information processing are discussed.magnified imageThe blinking of semiconductor colloidal nanocrystals is the main inconvenience of these bright nanoemitters. For some years, research on this phenomenon has demonstrated the possibility to progress beyond this problem by suppressing this fluorescence intermittency in various ways. After a brief overview on the microscopic mechanism of blinking, we review the various approaches used to obtain non‐blinking nanocrystals and discuss the commitment of this crucial improvement to applications in the fields of optoelectronic devices, biologic labelling and quantum information processing.
Adult neurogenesis in the crayfish brain: Proliferation, migration, and possible origin of precursor cells
Authors: Zhang Yi , Allodi Silvana , Sandeman David C. , Beltz Barbara S. 
Published: March 2009

AbstractThe birth of new neurons and their incorporation into functional circuits in the adult brain is a characteristic of many vertebrate and invertebrate organisms, including decapod crustaceans. Precursor cells maintaining life‐long proliferation in the brains of crayfish (Procambarus clarkii, Cherax destructor) and clawed lobsters (Homarus americanus) reside within a specialized niche on the ventral surface of the brain; their daughters migrate to two proliferation zones along a stream formed by processes of the niche precursors. Here they divide again, finally producing interneurons in the olfactory pathway. The present studies in P. clarkii explore (1) differential proliferative activity among the niche precursor cells with growth and aging, (2) morphological characteristics of cells in the niche and migratory streams, and (3) aspects of the cell cycle in this lineage. Morphologically symmetrical divisions of neuronal precursor cells were observed in the niche near where the migratory streams emerge, as well as in the streams and proliferation zones. The nuclei of migrating cells elongate and undergo shape changes consistent with nucleokinetic movement. LIS1, a highly conserved dynein‐binding protein, is expressed in cells in the migratory stream and neurogenic niche, implicating this protein in the translocation of crustacean brain neuronal precursor cells. Symmetrical divisions of the niche precursors and migration of both daughters raised the question of how the niche precursor pool is replenished. We present here preliminary evidence for an association between vascular cells and the niche precursors, which may relate to the life‐long growth and maintenance of the crustacean neurogenic niche. © 2009 Wiley Periodicals, Inc. Develop Neurobiol, 2009
Improving the sensitivity of negative controls in ancient DNA extractions
Authors: Xu Zhi , Zhang Fan , Xu Bosong , Tan Jingze , Li Shilin , Jin Li 
Published: March 2009

AbstractMuch attention has been paid on ancient DNA (aDNA) studies, and negative control was used as one of the stringent quality assurance criteria in order to detect potential contamination. However, the results of some aDNA studies showed the evidence of contamination despite their negative controls failed to do so. Using λ DNA to mock extraneous contaminating DNA, our study showed that aDNA had a property of improving the efficiency of extraction including contaminating DNA, while negative controls had low sensitivity to detect contamination. To circumvent this problem, carrier DNA such as poly(dA) is suggested to be introduced into aDNA extraction.
Lipid metabolite levels of prostaglandin D2 and eicosapentaenoic acid recovered from bronchoalveolar lavage fluid correlate with lung function of chronic obstructive pulmonary disease patients and controls
Authors: Csanky Ezster , Rühl Ralph , Scholtz Beata , Vasko Attila , Takacs Laszlo , Hempel William M. 
Published: March 2009

AbstractOne‐step global profiling of analyte (mRNA, protein, metabolite) biomarkers may soon replace conventional blood and histological/biopsy diagnostics technologies. It is important to establish whether the numerous blood and other body fluid‐derived potential novel diagnostics will be sufficiently efficacious and precise to replace, for example, imaging and functional diagnostic tests. Currently, imaging technologies and spirometry are indispensable for the diagnosis and management of chronic obstructive pulmonary disease (COPD). To validate the concept of using body fluid biomarkers in COPD and to address the question of whether biomarker levels correlate with lung function, we measured the level of a number of biologically relevant lipids and metabolites in the bronchoalveolar lavage (BAL) fluid of COPD and control subjects and examined whether these correlate with numeric parameters of lung function. Both the diagnosis and management of COPD rely on costly and labor intensive lung function tests. Thus, there is an imminent need to replace the current diagnostic approaches with simpler clinical assays. As a first step, we demonstrate proof of principle; the correlation of lipid biomarkers as measured by LC‐MS with lung function. In the apparently BAL‐accessible fluid compartment, the total recovered lipid metabolite amount, particularly prostaglandin D2 and eicosapentaenoic acid show a remarkable linear correlation with lung function (R2>0.7). The study outcome is encouraging for the continuation of the work toward the measurement of lipid metabolite levels in more easily obtainable biological fluids such as sputum, exhaled air condensate, urine and plasma.
Sampling from Dirichlet partitions: estimating the number of species
Authors: Huillet Thierry , Paroissin Christian 
Published: March 2009

AbstractThe Dirichlet partition of an interval can be viewed as the generalization of several classical models in ecological statistics. We recall the unordered Ewens sampling formulae ‐ESF) from finite Dirichlet partitions. As this is a key variable for estimation purposes, focus is on the number of distinct visited species in the sampling process. These are illustrated in specific cases. We use these preliminary statistical results on frequencies distribution to address the following sampling problem: what is the estimated number of species when sampling is from Dirichlet populations? The obtained results are in accordance with the ones found in sampling theory from random proportions with Poisson–Dirichlet ‐PD) distribution. To conclude with, we apply the different estimators suggested to two different sets of real data. Copyright © 2009 John Wiley & Sons, Ltd.
On spatial skew‐Gaussian processes and applications
Authors: Zhang Hao , El‐Shaarawi Abdel 
Published: March 2009

AbstractIn many applications, observed spatial variables have skewed distributions. It is often of interest to model the shape of the skewed marginal distributions as well as the spatial correlations. We propose a class of stationary processes that have skewed marginal distributions. The covariance function of the process can be given explicitly. We study maximum likelihood inference through a Monte Carlo EM algorithm, and develop a method for the minimum mean‐square error prediction. We also present two applications of the process. Copyright © 2009 John Wiley & Sons, Ltd.
Neural connectivity as an intermediate phenotype: Brain networks under genetic control
Authors: Meyer‐Lindenberg Andreas 
Published: March 2009

AbstractRecent evidence suggests that default mode connectivity characterizes neural states that account for a sizable proportion of brain activity and energy expenditure, and therefore represent a plausible neural intermediate phenotype. This implies the possibility of genetic control over systems‐level connectivity features. Imaging genetics is an approach to combine genetic assessment with multimodal neuroimaging to discover neural systems linked to genetic abnormalities or variation. In the present contribution, we report results obtained from applying this strategy to both structural connectivity and functional connectivity data. Using data for serotonergic (5‐HTTLPR, MAO‐A) and dopaminergic (DARPP‐32) genes as examples, we show that systems‐level connectivity networks under genetic control can be identified. Remarkable similarities are observed across modalities and scales of description. Features of connectivity often better account for behavioral effects of genetic variation than regional parameters of activation or structure. These data provide convergent evidence for genetic control in humans over connectivity systems, whose characterization has promise for identifying neural systems mediating genetic risk for complex human behavior and psychiatric disease. Hum Brain Mapp, 2009. © 2009 Wiley‐Liss, Inc.
Cortical mapping of naming errors in aphasia
Authors: Fridriksson Julius , Baker Julie M. , Moser Dana 
Published: March 2009

AbstractPersons with aphasia vary greatly with regard to clinical profile; yet, they all share one common feature—anomia—an impairment in naming common objects. Previous research has demonstrated that particular naming errors are associated with specific left hemisphere lesions. However, we know very little about the cortical activity in the preserved brain areas that is associated with aphasic speech errors. Utilizing functional magnetic resonance imaging (fMRI), we show for the first time that specific speech errors are associated with common cortical activity in different types and severities of aphasia. Specifically, productions of phonemic errors recruited the left posterior perilesional occipital and temporal lobe areas. A similar pattern of activity was associated with semantic errors, albeit in the right hemisphere. This study does not discount variability in cortical activity following left hemisphere stroke; rather, it highlights commonalities in brain modulation in a population of patients with a common diagnosis but vastly different clinical profiles. Hum Brain Mapp 2009. © 2009 Wiley‐Liss, Inc.
Beta‐amyloid protein (25–35) disrupts hippocampal network activity: Role of Fyn‐kinase
Authors: Peña Fernando , Ordaz Benito , Balleza‐Tapia Hugo , Bernal‐Pedraza Ramón , Márquez‐Ramos Abraham , Carmona‐Aparicio Liliana , Giordano Magda 
Published: March 2009

AbstractEarly cognitive deficit characteristic of early Alzheimer's disease seems to be produced by the soluble forms of β‐amyloid protein. Such cognitive deficit correlates with neuronal network dysfunction that is reflected as alterations in the electroencephalogram of both Alzheimer patients and transgenic murine models of such disease. Correspondingly, recent studies have demonstrated that chronic exposure to βAP affects hippocampal oscillatory properties. However, it is still unclear if such neuronal network dysfunction results from a direct action of βAP on the hippocampal circuit or it is secondary to the chronic presence of the protein in the brain. Therefore, we aimed to explore the effect of acute exposure to βAP25–35on hippocampal network activity both in vitro and in vivo, as well as on intrinsic and synaptic properties of hippocampal neurons. We found that βAP25–35, reversibly, affects spontaneous hippocampal population activity in vitro. Such effect is not produced by the inverse sequence βAP35–25and is reproduced by the full‐length peptide βAP1–42. Correspondingly βAP25–35, but not the inverse sequence βAP35–25, reduces theta‐like activity recorded from the hippocampus in vivo. The βAP25–35‐induced disruption in hippocampal network activity correlates with a reduction in spontaneous neuronal activity and synaptic transmission, as well as with an inhibition in the subthreshold oscillations produced by pyramidal neurons in vitro. Finally, we studied the involvement of Fyn‐kinase on the βAP25–35‐induced disruption in hippocampal network activity in vitro. Interestingly, we found that such phenomenon is not observed in slices obtained from Fyn‐knockout mice. In conclusion, our data suggest that βAP acutely affects proper hippocampal function through a Fyn‐dependent mechanism. We propose that such alteration might be related to the cognitive impairment observed, at least, during the early phases of Alzheimer's disease. © 2009 Wiley‐Liss, Inc.