bluuebunny/crossref_metadata_2025_split huggingface dataset:
Neuropsychological testing for the assessment of manganese neurotoxicity: A review and a proposal
Authors: Zoni Silvia , Albini Elisa , Lucchini Roberto 
Published: October 2007

AbstractBackgroundManganese exposure can cause neurobehavioral and neurological signs and symptoms. A review of the literature was carried out in order to identify the most sensitive and effective methods to assess these outcomes.MethodsStudies on manganese exposure performed with neuropsychological tests were reviewed using Medline. Test methods, obtained outcomes, and dose‐response relationships were considered. Based on the review and additional considerations, a testing battery for adult and children was identified.ResultsA total number of 31 studies were reviewed and divided in 18 occupational, 7 environmental, and 6 on children. A large variety of tests exploring motor and cognitive functions and mood were applied. Neurobehavioral effects were dose‐dependent in several studies and determined by much lower exposure levels compared to 1 mg Mn/m3 in total dust which is considered to be the minimum concentration able to induce the classical clinical features of “manganism.” Although through a wide variety of tests, the observed outcomes support the knowledge that manganese exposure can cause neurobehavioral effects. Motor functions are mainly affected in adults, and cognitive functions and behavior are more affected in children.ConclusionsLiterature on manganese neurobehavioral effect is quite consistent, however, further improvement may be achieved by using better structured and more comparable evaluation methods. Based on the analysis of the existing experiences a test battery including tests of motor functions, response speed, cognitive functions, intellectual abilities, mood, and symptom questionnaires is suggested. We recommend that the tests indicated should always be included in future studies as a core battery. Am. J. Ind. Med. 50:812–830, 2007. © 2007 Wiley‐Liss, Inc.
Niobium‐ and Tantalum‐Based Ethylene Polymerisation Catalysts Bearing Methylene‐ or Dimethyleneoxa‐Bridged Calixarene Ligands
Authors: Redshaw Carl , Rowan Michael , Homden Damien M. , Elsegood Mark R. J. , Yamato Takehiko , Pérez‐Casas Carol 
Published: October 2007

AbstractTreatment of p‐tert‐butylcalix[6]areneH6 (H6tBu‐L) or p‐tert‐butylcalix[8]areneH8 (H8tBu‐L1) with [MCl5] (M=Nb, Ta) in refluxing toluene or dichloromethane affords, after work‐up, the complexes [{M(NCMe)Cl2}2(tBu‐L)] (M=Nb (1), Ta (2)) and [(MCl2)2(tBu‐L1H2)] (M=Nb (4), Ta (5)), respectively. Complex 1, as well as [{Nb2(μ‐O)2(μ‐Cl)(tBu‐LH)}2] (3), is also available from [NbOCl3] and H6tBu‐L. Reaction of [MOCl3] (M=Nb, Ta) with Li3(tBu‐L2) in diethyl ether, where H3tBu‐L2 is p‐tert‐butylhexahomotrioxacalix[3]areneH3, affords, after work‐up, the trimeric complexes [{M(tBu‐L2)(μ‐O)}3] (M=Nb (6), Ta (7)). The behaviour of 1 to 7 (not 3), as well as the known complexes [{(MCl)p‐tert‐butylcalix[4]arene}2] (M=Nb (8), Ta (9)) and [(MCl2)p‐tert‐butylcalix[4]arene(OMe)] (M=Nb (10), Ta (11)), as pro‐catalysts for the polymerisation of ethylene has been investigated. In the presence of dimethyl (or diethyl)aluminium chloride, methylaluminoxane or trimethylaluminium, these niobium and tantalum procatalysts are all active (<35 g mmol−1 h−1 bar−1), for the polymerisation of ethylene affording high‐molecular‐weight linear polyethylene. The dimethyleneoxa‐bridged systems (derived from 6 and 7) are more active (84 and 46 g mmol−1 h−1 bar−1, respectively) than the methylene‐bridged systems. The molecular structures of 1–6 and 10 (acetonitrile solvate) are reported.
Highly Enantioselective Decarboxylative Protonation of α‐Aminomalonates Mediated by Thiourea Cinchona Alkaloid Derivatives: Access to Both Enantiomers of Cyclic and Acyclic α‐Aminoacids.
Authors: Amere Mukkanti , Lasne Marie‐Claire , Rouden Jacques 
Published: October 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Catalytic Method for the Reduction of Secondary and Tertiary Phosphine Oxides.
Authors: Berthod Mikael , Favre‐Reguillon Alain , Mohamad Jahjah , Mignani Gerard , Docherty Gordon , Lemaire Marc 
Published: October 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
High‐Yield Synthesis of Rhombohedral Boron Nitride Triangular Nanoplates.
Authors: Xu Liqiang , Zhan Jinhua , Hu Junqing , Bando Yoshio , Yuan Xiaoli , Sekiguchi Takashi , Mitome Masanori , Golberg Dmitri 
Published: October 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Radiation therapy is associated with improved survival in patients with pancreatic adenocarcinoma: Results of a study from the surveillance, epidemiology, and end results (SEER) registry data
Authors: Hazard Lisa , Tward Jonathan D , Szabo Aniko , Shrieve Dennis C 
Published: October 2007

AbstractBACKGROUND.The role of adjuvant radiation therapy in pancreatic cancer is controversial. For the current study, the authors evaluated the effect of preoperative and postoperative radiation therapy on survival in patients with pancreatic adenocarcinoma.METHODS.The analysis included 3008 patients who were reported to the Surveillance, Epidemiology, and End Results registry of the National Cancer Institute from 1988 to 2002 who had adenocarcinoma of the pancreas and who underwent cancer‐directed surgery. A retrospective analysis of overall survival and cancer‐specific survival for these patients was performed using the Kaplan‐Meier method. Comparative risks of mortality were evaluated by using multivariate‐adjusted Cox regression models.RESULTS.Of 3008 patients, 1267 (42%) received radiation therapy. Overall survival improved significantly in patients who received radiation therapy, with a median survival of 17 months and a 5‐year overall survival rate of 13% in patients who received radiation compared with 12 months and 9.7%, respectively, for patients who did not receive radiation therapy (P < .0001). On multivariate analysis, radiation therapy was associated with improvement in overall survival in patients who had direct extension beyond the pancreas and/or regional lymph node involvement (P < .01) but not in patients with T1‐T2N0M0 disease (P > .05). Radiation therapy was associated with improvement in cause‐specific survival in patients who had regional lymph node involvement (P < .02) but not in patients who had T1‐2N0M0 disease or direct extension beyond the pancreas without lymph node involvement (P > .05). Differences in overall and cause‐specific survival among patients who received preoperative versus postoperative radiation therapy did not reach statistical significance.CONCLUSIONS.Radiation therapy was associated with improved survival compared with cancer‐directed surgery without radiation in patients with adenocarcinoma of the pancreas. Cancer 2007 © 2007 American Cancer Society.
Arachidonic acid as a retrograde signal controlling growth and dynamics of retinotectal arbors
Authors: Leu B.H. , Schmidt J.T. 
Published: October 2007

AbstractIn the developing visual system, correlated presynaptic activity between neighboring retinal ganglion cells (RGC) stabilizes retinotopic synapses via a postsynaptic NMDAR (N‐methyl‐D‐aspartate receptor)‐dependent mechanism. Blocking NMDARs makes individual axonal arbors larger, which underlies an unsharpened map, and also increases branch turnover, as if a stabilizing factor from the postsynaptic partner is no longer released. Arachidonic acid (AA), a candidate retrograde stabilizing factor, is released by cytoplasmic phospholipase A2 (cPLA2) after Ca2+ entry through activated NMDARs, and can activate presynaptic protein kinase C to phosphorylate various substrates such as GAP43 to regulate cytoskeletal dynamics. To test the role of cPLA2 in the retinotectal system of developing zebrafish, we first used PED6, a fluorescent reporter of cPLA2 activity, to show that 1–3 min of strobe flashes activated tectal cPLA2 by an NMDAR‐dependent mechanism. Second, we imaged the dynamic growth of retinal arbors during both local inhibition of tectal cPLA2 by a pharmacological inhibitor, arachidonic tri‐fluoromethylketone, and its suppression by antisense oligonucleotides (both injected intraventricularly). Both methods produced larger arbors and faster branch dynamics as occurs with blocking NMDARs. In contrast, intraocular suppression of retinal cPLA2 with large doses of antisense oligos produced none of the effects of tectal cPLA2 inhibition. Finally, if AA is the retrograde messenger, the application of exogenous AA to the tectum should reverse the increased branch turnover caused by blocking either NMDARs or cPLA2. In both cases, intraventricular injection of AA stabilized the overall branch dynamics, bringing rates down below the normal values. The results suggest that AA generated postsynaptically by cPLA2 downstream of Ca2+ entry through NMDARs acts as a retrograde signal to regulate the dynamic growth of retinal arbors. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2008.
Overexpression of IL‐21 promotes massive CD8+ memory T cell accumulation
Authors: Allard Eve‐Line , Hardy Marie‐Pierre , Leignadier Julie , Marquis Miriam , Rooney Julie , Lehoux Dario , Labrecque Nathalie 
Published: October 2007

AbstractThe ability of IL‐21 to promote in vitro T cell survival led us to investigate its biological activity in vivo. We report that overexpression of IL‐21 in transgenic mice drives CD8+ memory T cell accumulation with a concomitant reduction in naive T cell numbers. These memory T cells are functional, given their ability to rapidly produce IFN‐γ and proliferate following stimulation. Since the homeostasis of naive and memory T cells is controlled by cytokines, we evaluated whether IL‐21 influences cytokine receptor expression. We show that IL‐21 inhibits IL‐7R expression on naive T cells in vitro, suggesting impaired IL‐7‐mediated naive T cell survival in IL‐21‐transgenic mice. In contrast, IL‐7R expression on CD4+ memory T cells is not affected, allowing their IL‐7‐dependent survival in IL‐21‐transgenic mice. Although IL‐21 decreases IL‐7R expression on CD8+ memory T cells, this has no impact on their survival since their maintenance in the T cell pool is IL‐7‐independent. Rather, we demonstrate that CD8+ memory T cells are receptive to IL‐21 survival signals allowing for their accumulation in IL‐21‐transgenic mice. This study identifies new roles for IL‐21 in T cell homeostasis and in the regulation of T cell responses to cytokines.
A critical lineage‐nonspecific role for pTα in mediating allelic and isotypic exclusion in TCRβ‐transgenic mice
Authors: Ferrero Isabel , Grosjean Frederic , Fiorini Emma , MacDonald H. Robson 
Published: October 2007

AbstractAlthough it is well established that early expression of TCRβ transgenes in the thymus leads to efficient inhibition of both endogenous TCRβ and TCRγ rearrangement (also known as allelic and “isotypic” exclusion, respectively) the role of pTα in these processes remains controversial. Here, we have systematically re‐evaluated this issue using three independent strains of TCRβ‐transgenic mice that differ widely in transgene expression levels, and a sensitive intracellular staining assay that detects endogenous TCRVβ expression in individual immature thymocytes. In the absence of pTα, both allelic and isotypic exclusion were reversed in all three TCRβ‐transgenic strains, clearly demonstrating a general requirement for pre‐TCR signaling in the inhibition of endogenous TCRβ and TCRγ rearrangement. Both allelic and isotypic exclusion were pTα dose dependent when transgenic TCRβ levels were subphysiological. Moreover, pTα‐dependent allelic and isotypic exclusion occurred in both αβ and γδ T cell lineages, indicating that pre‐TCR signaling can potentially be functional in γδ precursors. Finally, levels of endogenous RAG1 and RAG2 were not down‐regulated in TCRβ‐transgenic immature thymocytes undergoing allelic or isotypic exclusion. Collectively, our data reveal a critical but lineage‐nonspecific role for pTα in mediating both allelic and isotypic exclusion in TCRβ‐transgenic mice.
Deletion of the LIME adaptor protein minimally affects T and B cell development and function
Authors: Grégoire Claude , Simova Sarka , Wang Ying , Sansoni Amandine , Richelme Sylvie , Schmidt‐Giese Anja , Simeoni Luca , Angelisova Pavla , Reinhold Dirk , Schraven Burkhart , Horejsi Vaclav , Malissen Bernard , Malissen Marie 
Published: October 2007

AbstractLIME (Lck‐interacting membrane protein) is a transmembrane adaptor that associates with the Lck and Fyn protein tyrosine kinases and with the C‐terminal Src kinase (Csk). To delineate the role of LIME in vivo, LIME‐deficient mice were generated. Although Lime transcripts were expressed in immature and mature B and T cells, the absence of LIME impeded neither the development nor the function of B and T cells. TCR transgenic mice deprived of LIME showed, however, a 1.8‐fold enhancement in positive selection. Since B cells and activated T cells express LIME and the related adaptor NTAL, mice lacking both adaptors were generated. Double‐deficient mice showed no defect in the development and function of B and T cells, and the lack of LIME had no effect on the autoimmune syndrome that develops in aged NTAL‐deficient mice. In contrast to a previous report, we further showed that this autoimmune syndrome develops in the absence of T cells. Therefore, our in vivo results refute all the previous roles postulated for LIME on the basis of studies of transformed B and T cells and demonstrate that LIME has no seminal role in the signaling cassette operated by antigen receptors and coreceptors.
Exfoliated Graphite Oxide Modified Electrode for the Selective Determination of Picomolar Concentration of Lead
Authors: Ramesha G. K. , Sampath S. 
Published: October 2007

AbstractWe report the selective, picomolar determination of lead(II) ions using exfoliated graphite oxide (EGO) modified glassy carbon electrode. Exfoliated graphite oxide is the oxidized form of exfoliated graphite containing a variety of functional groups such as hydroxyl, phenolic and carboxyl groups. The EGO can be dispersed as a stable colloid in a wide range of pH, from 2 to 11. This leads to the flexibility of film formation on substrates and use of a variety of functional groups to complex lead ions. The analyte is preconcentrated and subsequently determined using differential pulse anodic stripping voltammetry. The factors influencing the determination of lead such as the pH of the analyte solution, preconcentration time and the thickness of EGO layer on the electrode surface have been optimized. Two linear ranges are observed between 1 mM and 10 μm and 0.1 μM and 1 pM for a 5 minute preconcentration time. The lowest detection limit is found to be 1 pM. The main advantages of the electrode are the ease of preparation of the modified electrode, low cost, sensitivity and selectivity. The analytical utility of the EGO modified electrode in the determination of lead is demonstrated by application to several water samples.
Novel NO2 Gas Sensor Based on Cr(III) Complex Thin Film
Authors: Fu Tiexiang 
Published: October 2007

AbstractThe results concerning the gas‐sensing characteristics of novel NO2 gas sensors, fabricated from complex [Cr(bipyO2)Cl2]Cl thin films, were first presented. The sensors exhibited high response to NO2 gas in the concentration range from 1.97% to 6.67% at relative low temperatures (from room temperature to 348 K). No response to H2S and SO2 was observed. The maximum response for 6.03% NO2 was approximately 11.7 at 338 K and 10 V operating voltage. The response time of the sensors was about 4.5 min for NO2 and the recovery time about 40 s. The effect of the electrical resistance change of the sensors in the presence of NO2 could be used for gas sensing measurements. The performance and reliability of the sensors showed their potential applications for monitoring and controlling NO2 component continuously in chemical production.
Estimating evapotranspiration from small watersheds using a water and energy balance approach
Authors: Rim Chang‐Soo 
Published: October 2007

AbstractMeteorological and environmental data measured in semiarid watersheds during the summer monsoon and winter periods were used to study the interrelationships among flux, meteorological and soil water variables, and to evaluate the effects of these variables on the daily estimation of actual evapotranspiration (AET). The relationship between AET and potential evapotranspiration (PET) as a function of soil water content, as suggested by Thornthwaite–Mather and by Morton, was studied to determine its applicability to the study area. Furthermore, multiple linear regression (MLR) analysis was employed to evaluate the order of importance of the meteorological and soil water factors involved.The results of MLR analysis showed that the combined effects of available energy, soil water content and wind speed were responsible for more than 70% of the observed variations in AET during the summer monsoon period. The analyses also indicate that the combined effects of available energy, vapour pressure deficit and wind speed were responsible for more than 70% of the observed variations in AET during the winter period. However, the test results of two different approaches, using the relationships between AET and PET as a function of soil water content, indicated some inadequacy. Copyright © 2007 John Wiley & Sons, Ltd.
Hydrochemical appraisal of ice‐ and rock‐glacier meltwater in the hyperarid Agua Negra drainage basin, Andes of Argentina
Authors: Lecomte Karina L. , Milana Juan Pablo , Formica Stella M. , Depetris Pedro J. 
Published: October 2007

AbstractThe Agua Negra drainage system (30 12′S, 69 50′ W), in the Argentine Andes holds several ice‐ and rock‐glaciers, which are distributed from 4200 up to 6300 m a.s.l. The geochemical study of meltwaters reveals that ice‐glaciers deliver a HCO3−Ca2+ solution and rock‐glaciers a SO42−HCO3−Ca2+ solution. The site is presumably strongly influenced by sublimation and dry deposition. The main processes supplying solutes to meltwater are sulphide oxidation (i.e. abundant hydrothermal manifestations), and hydrolysis and dissolution of carbonates and silicates. Marine aerosols are the main source of NaCl. The fine‐grained products of glacial comminution play a significant role in the control of dissolved minor and trace elements: transition metals (e.g. Mn, Zr, Cu, and Co) appear to be selectively removed from solution, whereas some LIL (large ion lithophile) elements, such as Sr, Cs, and major cations, are more concentrated in the lowermost reach. Daily concentration variation of dissolved rare earth elements (REE) tends to increase with discharge. Through PHREEQC inverse modelling, it is shown that gypsum dissolution (i.e. sulphide oxidation) is the most important geochemical mechanism delivering solutes to the Agua Negra drainage system, particularly in rock‐glaciers. At the lowermost reach, the chemical signature appears to change depending on the relative significance of different meltwater sources: silicate weathering seems to be more important when meltwater has a longer residence time, and calcite and gypsum dissolution is more conspicuous in recently melted waters. A comparison with a non‐glacierized semiarid drainage of comparable size shows that the glacierized basin has a higher specific denudation, but it is mostly accounted for by relatively soluble phases (i.e. gypsum and calcite). Meltwater chemistry in glacierized arid areas appears strongly influenced by sublimation/evaporation, in contrast with its humid counterparts. Copyright © 2007 John Wiley & Sons, Ltd.
Tumor‐selective vessel occlusions by platelets after vascular targeting chemotherapy using paclitaxel encapsulated in cationic liposomes
Authors: Strieth Sebastian , Nussbaum Claudia F. , Eichhorn Martin E. , Fuhrmann Martin , Teifel Michael , Michaelis Uwe , Berghaus Alexander , Dellian Marc 
Published: October 2007

AbstractPaclitaxel encapsulated in cationic liposomes (EndoTAG‐1) significantly impairs tumor growth by a significant reduction of functional tumor microcirculation and induction of endothelial cell apoptosis. The aim of the study was to analyze whether platelet activation within the tumor microcirculation contributes to the antivascular effects of vascular targeting chemotherapy using EndoTAG‐1. In vitro, FACS analysis revealed a significant activation of platelets upon treatment with EndoTAG‐1. In vivo, using A‐Mel‐3 tumors in Syrian Golden hamsters equipped with dorsal skinfold chamber preparations, the contribution of platelets to the antivascular effects of EndoTAG‐1 was evaluated by fluorescence and laser‐scanning microscopy. Immediately after a single treatment with EndoTAG‐1 or cationic liposomes devoid of paclitaxel, an increase of platelet adherence in tumor microvessels was observed. This was accompanied by an acute impairment of the microcirculation within the treated tumors leading to reduced tumor perfusion. After repetitive therapy, an increase of platelet adherence and subsequent tumor microvessel occlusions occurred only after treatment with EndoTAG‐1. Comparing to “tumor free” normal tissue controls these microthromboses were tumor selective. Significantly disbalancing the coagulation system within tumors by targeted induction of microthromboses within the tumor microcirculation appears to be an important mechanism of EndoTAG‐1 therapy. © 2007 Wiley‐Liss, Inc.
Germline mutations in the CHEK2 kinase gene are associated with an increased risk of bladder cancer
Authors: Złowocka Elżbieta , Cybulski Cezary , Górski Bohdan , Dębniak Tadeusz , Słojewski Marcin , Wokołorczyk Dominika , Serrano‐Fernández Pablo , Matyjasik Joanna , van de Wetering Thierry , Sikorski Andrzej , Scott Rodney J. , Lubiński Jan 
Published: October 2007

AbstractGermline mutations in CHEK2 have been associated with a range of cancer types but little is known about disease risks conveyed by CHEK2 mutations outside of the context of breast and prostate cancer. To investigate whether CHEK2 mutations confer an increased risk of bladder cancer, we genotyped 416 unselected cases of bladder cancer and 3,313 controls from Poland for 4 founder alleles in the CHEK2 gene, each of which has been associated with an increased risk of cancer at other sites. A CHEK2 mutation (all variants combined) was found in 10.6% of the cancer cases and in 5.9% of the controls (OR = 1.9; 95%CI 1.3–2.7; p = 0.0003). We conclude that CHEK2 mutations increase the risk of bladder cancer in the population. © 2007 Wiley‐Liss, Inc.
Meta‐analysis in model implementation: choice sets and the valuation of air quality improvements
Authors: Banzhaf H. Spencer , Smith V. Kerry 
Published: October 2007

AbstractThis research illustrates how the methods developed for meta‐analysis can serve to document and summarize voluminous information derived from repeated sensitivity analyses. Our application is to the sensitivity of welfare estimates derived from discrete choice models to assumptions about the choice set. These assumptions affect welfare estimates through both the estimated parameters of the model and, conditional on the parameters, the substitution among alternatives. In our specific application, the evaluation is in terms of estimated benefits of air quality improvements in Los Angeles based on discrete choices of neighborhood and housing. Copyright © 2007 John Wiley & Sons, Ltd.