bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of the glycaemic index of pre‐exercise carbohydrate meals on running performance
Authors: Wong Stephen H. S. , Siu Parco M. , Lok Andy , Chen Y. J. , Morris John , Lam C. W. 
Published: February 2008

AbstractThe aim of this study was to examine the effect of pre‐exercise low and high glycaemic index (GI) carbohydrate meals on running performance. Eight endurance‐trained male runners (mean age 33 years, s x =1.7; 63 ml · kg−1 · min−1, s x =1.8) completed two trials separated by at least 7 days in a counterbalanced design. Two hours before they were to run and after an overnight fast, each participant consumed an isocaloric meal containing either low (gi=37) or high (gi=77) GI carbohydrate foods (2.4 MJ; 65% carbohydrate; 15% protein; 20% fat) that provided 1.5 g carbohydrate per kilogram of body mass in random order. Each trial consisted of a 21‐km performance run on a level treadmill. The participants were required to run at 70% during the first 5 km of the run. They subsequently completed the remaining 16 km in as short a time as possible. All participants achieved a faster performance time after the consumption of the low GI meal (low vs. high GI: 98.7 min, s x =2 vs. 101.5 min, s x =2; P<0.01). Blood glucose and serum free fatty acids concentrations were higher throughout the performance run in the low GI trial. Serum insulin concentrations were higher in the high GI trial during the postpandial resting period. However, there were no differences between trials in serum insulin or blood lactate concentrations throughout exercise. Compared with the high GI trial, carbohydrate oxidation was 9.5% lower and fat oxidation was 17.9% higher during exercise in the low GI trial. In conclusion, our results indicate that compared with an isocaloric high GI meal, the consumption of a low GI meal 2 h before a 21‐km performance run is a more effective means of improving performance time.
ITALICS: an algorithm for normalization and DNA copy number calling for Affymetrix SNP arrays
Authors: Rigaill Guillem , Hupé Philippe , Almeida Anna , La Rosa Philippe , Meyniel Jean-Philippe , Decraene Charles , Barillot Emmanuel 
Published: February 2008

AbstractMotivation: Affymetrix SNP arrays can be used to determine the DNA copy number measurement of 11 000–500 000 SNPs along the genome. Their high density facilitates the precise localization of genomic alterations and makes them a powerful tool for studies of cancers and copy number polymorphism. Like other microarray technologies it is influenced by non-relevant sources of variation, requiring correction. Moreover, the amplitude of variation induced by non-relevant effects is similar or greater than the biologically relevant effect (i.e. true copy number), making it difficult to estimate non-relevant effects accurately without including the biologically relevant effect.Results: We addressed this problem by developing ITALICS, a normalization method that estimates both biological and non-relevant effects in an alternate, iterative manner, accurately eliminating irrelevant effects. We compared our normalization method with other existing and available methods, and found that ITALICS outperformed these methods for several in-house datasets and one public dataset. These results were validated biologically by quantitative PCR.Availability: The R package ITALICS (ITerative and Alternative normaLIzation and Copy number calling for affymetrix Snp arrays) has been submitted to Bioconductor.Contact: italics@curie.frSupplementary information: Supplementary data are available at Bioinformatics online.
Aberrant splicing and protease involvement in mesothelin release from epithelioid mesothelioma cells
Authors: Sapede Carole , Gauvrit Anne , Barbieux Isabelle , Padieu Martine , Cellerin Laurent , Sagan Christine , Scherpereel Arnaud , Dabouis Gérard , Grégoire Marc 
Published: February 2008

Elevated amounts of soluble mesothelin‐related proteins (SMRP) have already been reported in sera and pleural effusions from mesothelioma patients, providing a useful diagnostic marker for malignant pleural mesothelioma (MPM). However, the origin of SMRP is not yet understood. Production of SMRP could be related to abnormal splicing events leading to synthesis of a secreted protein (release) or to an enzymatic cleavage from membrane‐bound mesothelin (ectodomain shedding). To test these hypotheses, we used a panel of mesothelioma cells established in culture from pleural effusions of MPM patients. Our in vitro results confirmed specific mesothelin expression and SMRP production in supernatants from epithelioid MPM cell lines, thus providing a relevant cellular model to study soluble mesothelin production mechanisms. The expression of mesothelin‐encoding RNA variants was screened by reverse transcription–polymerase chain reaction experiments. Protease involvement in mesothelin cleavage from the cellular surface was investigated by treatment of MPM cells with GM6001, a broad‐spectrum MMP‐ and ADAM‐family inhibitor. GM6001 treatment significantly impaired SMRP production by MPM cell lines, in favor of an enzymatic‐mediated shedding process. In addition, a splice variant transcript of mesothelin (variant 3) was detected in these MPM cell lines, in accordance with the release of a secreted part of the protein. Our results indicate that both mechanisms could be implicated in soluble mesothelin production by epithelioid mesothelioma cells. (Cancer Sci 2008; 99: 590–594)
Suppression of anoikis by the neurotrophic receptor TrkB in human ovarian cancer
Authors: Yu Xiaohui , Liu Ling , Cai Bin , He Yinyan , Wan Xiaoping 
Published: February 2008

TrkB is a neurotrophic tyrosine kinase receptor (Trk). To investigate its role in anoikis suppression in human ovarian cancer, we used reverse transcription–polymerase chain reaction and real‐time polymerase chain reaction, immunohistochemistry, and western blotting to compare the expression levels of TrkB and its ligand brain‐derived neurotrophic factor between (i) 20 epithelial ovarian cancers, their multicellular spheroids in ascites or great omentum metastatic lesions, and eight borderline or benign ovarian tumors, as well as four normal ovarian tissues; and (ii) three ovarian cancer cell lines cultured under different conditions: monolayer adhesive culture (adhesive cells), anchorage‐independent culture (cell spheroids), and trypsinized cell spheroids placed in monolayer adhesive dishes (cell spheroids replaced). TrkB and brain‐derived neurotrophic factor were overexpressed in epithelial ovarian cancers, and full‐length TrkB was more often overexpressed in high‐grade carcinomas and multicellular spheroids in ascites. Expression of TrkB mRNA was higher in OVCAR‐3 cell spheroids than in adhesive cells. The expression of full‐length TrkB protein was highest in OVCAR‐3 cell spheroids, but its precursor was expressed highly in OVCAR‐3 cells under all three culture conditions. The relationship between TrkB overexpression and phosphatidylinositol 3′‐kinase (PI3K)–AKT pathway activation in OVCAR‐3 cells was studied by western blotting and RNA interference. The PI3K–AKT pathway was highly activated in anoikis‐survived cells and was inhibited when TrkB was silenced by small interfering RNA. Finally, the chemosensitivity and invasiveness of OVCAR‐3 cells were examined by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium, fluorescence‐activated cell sorting, Matrigel invasion assay, and in vivo studies. Adhesive cells showed higher chemosensitivity and lower invasion ability than anoikis‐survived cells. Our study suggests that TrkB might mediate anoikis suppression by activating the PI3K–AKT pathway in ovarian cancer cells. (Cancer Sci 2008; 99: 543–552)
The genetics of nicotine addiction liability: ethical and social policy implications
Authors: Hall Wayne D. , Gartner Coral E. , Carter Adrian 
Published: February 2008

ABSTRACTAim  To assess the promise and risks of technological applications of genetic research on liability to develop nicotine dependence.Methods  We reviewed (i) the evidence on the genetics of nicotine dependence; (ii) the technical feasibility of using genetic information to reduce smoking uptake and increase cessation; and (iii) policy and ethical issues raised by the uses of genetic information on addiction liability.Results  (i) Despite evidence from twin studies that genes contribute to addiction susceptibility, research to date has not identified commonly occurring alleles that are strongly predictive of developing nicotine addiction. Nicotine addiction is likely to involve multiple alleles of small effect that interact with each other and with the environment. (ii) Population screening for susceptibility alleles is unlikely to be effective or cost‐effective. Tailoring of smoking cessation treatments with genetic information is more plausible but results to date have been disappointing. Population health strategies such as increased taxation and reduced opportunities to smoke are more efficient in reducing cigarette smoking. Tobacco harm reduction policies applied to populations may also play a role in reducing tobacco‐related harm. (iii) Future uses of genomic information on addiction risk will need to assess the risks of medicalising addiction (e.g. pessimism about capacity to quit) and community concerns about genetic privacy.Conclusions  Nicotine genomics is a very new and underdeveloped field. On the evidence to date, its advocates would be wise to avoid extravagant claims about its preventive applications.
Estimation of dose requirements for sustainedin vivoactivity of a therapeutic human anti‐CD20 antibody
Authors: Bleeker Wim K. , Munk Martin E. , Mackus Wendy J. M. , Van Den Brakel Jeroen H. N. , Pluyter Marielle , Glennie Martin J. , Van De Winkel Jan G. J. , Parren Paul W. H. I. 
Published: February 2008

SummaryWe evaluated the dose requirements for sustainedin vivoactivity of ofatumumab, a human anti‐CD20 antibody under development for the treatment of B cell‐mediated diseases. In a mouse xenograft model, a single dose, resulting in an initial plasma antibody concentration of 5 μg/ml, which was expected to result in full target saturation, effectively inhibited human B‐cell tumour development. Tumour growth resumed when plasma concentrations dropped below levels that are expected to result in half‐maximal saturation. Notably, tumour load significantly impacted antibody pharmacokinetics. In monkeys, initial depletion of circulating and tissue residing B cells required relatively high‐dose levels. Re‐population of B‐cell compartments, however, only became detectable when ofatumumab levels dropped below 10 μg/ml. We conclude that, once saturation of CD20 throughout the body has been reached by high initial dosing, plasma concentrations that maintain target saturation on circulating cells (5–10 μg/ml) are probably sufficient for sustained biological activity. These observations may provide a rationale for establishing dosing schedules for maintenance immunotherapy following initial depletion of CD20 positive (tumour) cells.
Polyandry and paternity skew in natural and experimental populations of Drosophila serrata
Authors: FRENTIU FRANCESCA D. , CHENOWETH STEPHEN F. 
Published: February 2008

AbstractMany species engage in polyandry, resulting in the potential for sexual selection to continue post‐copulation through sperm competition and/or cryptic female choice. The relative importance of pre‐ vs. post‐copulatory processes remains unknown for most species despite this information being fundamental for understanding the evolutionary consequences of sexual selection. The Australian fruit fly Drosophila serrata has become a prominent model system for studying precopulatory sexual selection, such as mating preferences and their influence on the evolution of sexually selected traits. Here, we investigated polyandry and the potential for post‐copulatory sexual selection in this species using indirect paternity analysis. We genotyped 21 wild‐caught and 19 laboratory‐reared mothers and their offspring (a total of 787 flies) at six microsatellite loci and found extensive polyandry, with all broods surveyed having at least two sires. Female remating rates were higher than in other Drosophila surveyed to date and no significant differences were found between laboratory and field populations. Additionally, we found evidence for biased sperm usage in several broods of D. serrata. Paternity skew occurred more frequently in broods from the field population than the laboratory one, suggesting differences between the two environments in the level of post‐copulatory sexual selection. Our data suggest that D. serrata represents a promising system for studying the interaction between pre‐ and post‐copulatory sexual selection in driving the evolution of sexually selected phenotypes.
‘Social heterosis’ as a process that maintains genetic variation – a comment
Authors: SANTOS M. 
Published: February 2008

AbstractIn the ‘mating pool’ mode of reproduction, offspring genotypes at each generation are taken randomly from a common population and subdivided into groups where individuals representing a finite sample from the pooled distribution reproduce proportional to their fitness. Assuming that genetically diverse groups contribute more offspring, a recent article by Nonacs & Kapheim [J. Evol. Biol. 20 (2007) 2253] shows that allelic diversity can be easily maintained and proposes the process of ‘social heterosis’ as a potentially powerful mechanism that accounts for a significant amount of genetic variation. Contrary to their suggestions, I show here that there is a reduced efficiency of selection and an increased probability of fixation of segregating alleles when many loci are simultaneously undergoing social heterosis even if independence of action of the different loci and linkage equilibrium are assumed. The critical issue is that linkage disequilibria are generated by the sampling process of creating small groups and interfere with selection.
Phenotypic integration and conserved covariance structure in calopterygid damselflies
Authors: EROUKHMANOFF F. , SVENSSON E. I. 
Published: February 2008

AbstractBy comparing the phenotypic (P) variance–covariance matrices between closely related taxa or conspecific populations, one can study the outcome of the interplay between selection and developmental constraints in phenotypic evolution. Shared patterns of phenotypic integration are also of interest and might result from similarities in either selection or developmental pathways. We comparedP‐matrices and phenotypic integration indices between populations and species of the damselfly genusCalopteryx.Pmax‐comparisons between parapatricC. splendenspopulations revealed stronger conserved phenotypic covariance structure thanPmax‐comparisons between species, suggesting that divergence in its early stages proceeds along phenotypic lines of least resistance. Within‐ and among‐population correlations inC. splendenswere highly concordant, in further support of initial divergence alongPmax. Despite some similarities in overall phenotypic integration betweenC. splendensandC. virgo, these two species only had severalP‐matrix eigenvectors in common, indicating that after reproductive isolation, divergence has proceeded againstPmax.
Rapid evolution towards heavy metal resistance by mountain birch around two subarctic copper–nickel smelters
Authors: ERÄNEN J. K. 
Published: February 2008

AbstractAdaptations to pollution among long‐lived trees have rarely been documented, possibly because of their long reproductive cycles and the evolutionarily short timescales of anthropogenic pollution. Here, I present the results of a greenhouse experiment that suggest rapid evolutionary adaptation of mountain birch [Betula pubescenssubsp.czerepanovii(Orlova) Hämet‐Ahti] to heavy metal (HM) stress around two copper–nickel smelters in NW Russia. The adaptation incurs a cost with reduced performance of adapted seedlings in pristine conditions. The industrial barrens around the studied smelters are extremely high‐stress sites with low seed germination and survival. It is likely that strong natural selection has eliminated all sensitive genotypes within one or two generations, with only the most tolerant individuals persisting and producing adapted seeds in the individual barrens. The results were similar from around both smelters, suggesting parallel evolution towards HM resistance.
Correlated evolution between male ejaculate allocation and female remating behaviour in seed beetles (Bruchidae)
Authors: KATVALA M. , RÖNN J. L. , ARNQVIST G. 
Published: February 2008

AbstractSperm competition theory suggests that female remating rate determines the selective regime that dictates the evolution of male ejaculate allocation. To test for correlated evolution between female remating behaviour and male ejaculate traits, we subjected detailed experimental data on female and male reproductive traits in seven‐seed beetle species to phylogenetic comparative analyses. The evolution of a larger first ejaculate was positively correlated with the evolution of a more rapid decline in ejaculate size over successive matings. Further, as predicted by theory, an increase in female remating rate correlated with the evolution of larger male testes but smaller ejaculates. However, an increase in female remating was associated with the evolution of a less even allocation of ejaculate resources over successive matings, contrary to classic sperm competition theory. We failed to find any evidence for coevolution between the pattern of male ejaculate allocation and variation in female quality and we conclude that some patterns of correlated evolution are congruent with current theory, whereas some are not. We suggest that this may reflect the fact that much sperm competition theory does not fully incorporate other factors that may affect the evolution of male and female traits, such as trade‐offs between ejaculate expenditure and other competing demands and the evolution of resource acquisition.
Evolution of sex‐biased maternal effects in birds. IV. Intra‐ovarian growth dynamics can link sex determination and sex‐specific acquisition of resources
Authors: BADYAEV A. V. , YOUNG R. L. , HILL G. E. , DUCKWORTH R. A. 
Published: February 2008

AbstractThe evolutionary importance of maternal effects is determined by the interplay of maternal adaptations and strategies, offspring susceptibility to these strategies, and the similarity of selection pressures between the two generations. Interaction among these components, especially in species where males and females differ in the costs and requirements of growth, limits inference about the evolution of maternal strategies from their expression in the offspring phenotype alone. As an alternative approach, we examine divergence in the proximate mechanisms underlying maternal effects across three house finch populations with contrasting patterns of sex allocation: an ancestral population that shows no sex‐biased ovulation, and two recently established populations at the northern and southern boundaries of the species range that have opposite sequences of ovulation of male and female eggs. For each population, we examined how oocyte acquisition of hormones, carotenoids and vitamins was affected by oocyte growth and overlap with the same and opposite sexes. Our results suggest that sex‐specific acquisition of maternal resources and sex determination of oocytes are linked in this system. We report that acquisition of testosterone by oocytes that become males was not related to growth duration, but instead covaried with temporal exposure to steroids and overlap with other male oocytes. In female oocytes, testosterone acquisition increased with the duration of growth and overlap with male oocytes, but decreased with overlap with female oocytes. By contrast, acquisition of carotenoids and vitamins was mostly determined by organism‐wide partitioning among oocytes and oocyte‐specific patterns of testosterone accumulation, and these effects did not differ between the sexes. These results provide important insights into three unresolved phenomena in the evolution of maternal effects – (i) the evolution of sex‐specific maternal allocation in species with simultaneously developing neonates of both sexes; (ii) the link between sex determination and sex‐specific acquisition of maternal products; and (iii) the evolution of context‐dependent modulation of maternal effects.
Incidence of Prunus necrotic ring spot virus on Malus domestica in India
Authors: Chandel V. , Rana T. , Handa A. , Thakur P. D. , Hallan V. , Zaidi A. A. 
Published: February 2008

AbstractIn surveys of apple (Malus domestica) orchards in various parts of Himachal Pradesh, samples from trees showing necrotic symptoms on the leaves were collected and tested for detection of Prunus necrotic ringspot virus (PNRSV) initially by ELISA followed by RT‐PCR using coat protein gene primers. Positive results were obtained in samples from Kullu and Kalpa regions. The virus gene sequences showed 88–97% similarity to corresponding sequences of other PNRSV isolates deposited in the GenBank database using ncbi.nih.nlm.gov. Although the similarity was high, there were some distinct differences with the Spanish isolate. This is the first report of PNRSV in apple from India.
INITIAL FRACTURE MECHANISMS IN NICKEL ALLOYED PM STEEL
Authors: Drar H. , Bergmark A. 
Published: February 2008

Abstract—Initial fatigue crack propagation mechanisms at near threshold conditions were studied for four nickel‐alloyed, powder‐metallurgy (PM) steels. Fatigue fracture surfaces were obtained by testing smooth rectangular specimens at 30 Hz and under constant amplitude and zero mean stress conditions. Materials based on Distaloy AE were used in two densities, namely 7.15 and 7.45 g/cm3.All the fracture surfaces were composed of three morphological regions (i) a macrocrack initiation region Rl where cracks propagated preferentially through particles (ii) a macrocrack growth region R2 and (iii) an unstable crack growth region R3 where cracks propagated preferentially between particles. Initial fatigue crack growth, in region R1, was controlled by the propagation of short cracks whose dimensions were comparable to the material microstructure. The subsequent fatigue crack growth in regions R2 and R3 was controlled by ductile rupture between microvoids. Transparticle fracture in region R1 was independent of pore distribution, while interparticle fracture in regions R2 and R3 was dependent on pore distribution.
The ‘digital natives’ debate: A critical review of the evidence
Authors: Bennett Sue , Maton Karl , Kervin Lisa 
Published: February 2008

AbstractThe idea that a new generation of students is entering the education system has excited recent attention among educators and education commentators. Termed ‘digital natives’ or the ‘Net generation’, these young people are said to have been immersed in technology all their lives, imbuing them with sophisticated technical skills and learning preferences for which traditional education is unprepared. Grand claims are being made about the nature of this generational change and about the urgent necessity for educational reform in response. A sense of impending crisis pervades this debate. However, the actual situation is far from clear. In this paper, the authors draw on the fields of education and sociology to analyse the digital natives debate. The paper presents and questions the main claims made about digital natives and analyses the nature of the debate itself. We argue that rather than being empirically and theoretically informed, the debate can be likened to an academic form of a ‘moral panic’. We propose that a more measured and disinterested approach is now required to investigate ‘digital natives’ and their implications for education.