bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitation of glutathione by liquid chromatography/positive electrospray ionization tandem mass spectrometry
Authors: Zhang Fagen , Bartels Michael J. , Geter David R. , Jeong Yo‐Chan , Schisler Melissa R. , Wood Amanda J. , Kan Lynn , Gollapudi B. Bhaskar 
Published: October 2008

AbstractGlutathione (GSH) is a tripeptide composed of glutamate, cysteine, and glycine. It is present in practically all cells and has several important roles, such as preventing the oxidation of the sulfhydryl groups of proteins within a cell. Evidence for GSH deficiency or depletion has been found in a variety of diseases and toxicity‐related studies, including diabetes and induction of oxidative stress to form reactive oxygen species which cause DNA, lipid, and protein oxidations. A simple, selective, and sensitive analytical method for measuring low levels of GSH in biological fluids would therefore be desirable to conduct GSH deficiency or depletion‐related mechanistic toxicity studies. Here a method for both low‐ and high‐level quantitation of GSH from cultured cells and rat liver tissues via liquid chromatography/positive electrospray ionization tandem mass spectrometry (LC/ESI‐MS/MS) has been developed. The lower limit of quantitation (LOQ) of the method was 5 ng/mL. The method is linear over a wide dynamic concentration range of 5.0 to 5000.0 ng/mL, with a correlation coefficient R2 > 0.99. The intra‐day assay precision relative standard deviation (RSD) values for all quality control (QC) samples were ≤16.31%, with accuracy values ranging from 94.13 to 97.80%. The inter‐day assay precision RSD values for all QC samples were ≤15.94%, with accuracy values ranging from 94.51 to 100.29%. With this method, low levels of GSH from diethyl maleate (DEM)‐treated mouse lymphoma cells, and GSH in rat liver tissues, were quantified. Copyright © 2008 John Wiley & Sons, Ltd.
Stability radii of positive linear systems under fractional perturbations
Authors: Anh Bui The , Son Nguyen Khoa 
Published: October 2008

AbstractIn this paper we study stability radii of positive linear discrete‐time systems under fractional perturbations. It is shown that real and complex stability radii coincide and can be computed by a simple formula. From the obtained results, we apply to derive estimates and computable formulae for the stability radii of positive linear delay systems. Finally, a simple example is given to illustrate the obtained results. Copyright © 2008 John Wiley & Sons, Ltd.
The universal common good: faith‐based partnerships and sustainable development
Authors: Morse Stephen , McNamara Nora 
Published: October 2008

AbstractPartnership is increasingly espoused as the best relationship between members of the sustainable development aid chain, and implies a respect for the position of all and a desire to avoid a situation where one group dominates another. It also implies a form of relationship that is not just ‘better’ for the sake of it but that is more able to help achieve sustainable development. However, given the inevitable inequalities in power between donors that have the resources and field partners that do not it can be hard to put this ideal into practice. This paper explores the function of partnership within a group of closely related institutions that comprise the Catholic Church development chain. The research focussed on three Catholic Church based donors (one from the USA and two from Europe) and their partners in Abuja Ecclesiastical Province, Nigeria. Relationships between and within various strata of the Church in Nigeria were also examined. Relationships were ‘patchy’ at all levels. One of the donors had a significant operational presence in Nigeria and this was regarded by some respondents as a parallel structure that seriously undermined local bodies. However, while problems existed, there was a sense of inter‐dependence arising from a shared sense of values and Catholic Social Teaching, which allowed partners to work through their stresses and conflicts. It is the innate sustainability of the aid chain itself founded upon a set of shared values that provided the space and time for problems to be addressed. Copyright © 2008 John Wiley & Sons, Ltd and ERP Environment.
South Africa's working for water programme: searching for win–win outcomes for people and the environment
Authors: Buch Andrea , Dixon Alan B. 
Published: October 2008

AbstractPoverty reduction and environmental conservation have rarely been integrated within development programmes. In South Africa, however, the government's Working for Water Programme (WfW) has sought to empower the most marginalized in society through the creation of jobs and training opportunities in the clearance of invasive alien plants that threaten water resources and biodiversity. Although the environmental benefits of the programme have been demonstrated, there is emerging concern that the social development goals are overly ambitious and impractical. Drawing upon recent field research undertaken in the Western Cape, this paper explores the realities of people's participation in the WfW programme. It argues that, whilst WfW has produced some positive tangible social development outcomes, these are neither substantial nor sustainable. Of arguably greater significance is a range of hitherto overlooked intangible social development outcomes, which if recognized, supported and integrated more fully into the programme could lead to a more sustainable future for South Africa's people and environment. Copyright © 2008 John Wiley & Sons, Ltd and ERP Environment.
Carbon emissions in Central and Eastern Europe: environmental Kuznets curve and implications for sustainable development
Authors: Atici Cemal 
Published: October 2008

AbstractThis study examines the impact of various factors such as gross domestic product (GDP) per capita, energy use per capita and trade openness on carbon dioxide (CO2) emission per capita in the Central and Eastern European Countries. The extended environmental Kuznets curve (EKC) was employed, utilizing the available panel data from 1980 to 2002 for Bulgaria, Hungary, Romania and Turkey. The results confirm the existence of an EKC for the region such that CO2 emission per capita decreases over time as the per capita GDP increases. Energy use per capita is a significant factor that causes pollution in the region, indicating that the region produces environmentally unclean energy. The trade openness variable implies that globalization has not facilitated the emission level in the region. The results imply that the region needs environmentally cleaner technologies in energy production to achieve sustainable development. Copyright © 2008 John Wiley & Sons, Ltd and ERP Environment.
How can the construction industry contribute to sustainable development? A conceptual framework
Authors: Sev Aysin 
Published: October 2008

AbstractThe importance of the construction industry for the three elements of sustainable development, namely economic growth, social progress and effective protection of the environment, cannot be disregarded. This paper aims to evolve a conceptual framework for implementing sustainability principles and strategies to the construction industry from a life‐cycle perspective to contribute to sustainable development. The framework relies on three basic principles, which are resource management, life‐cycle design and design for human and environment. Following a literature review, each principle involving strategies and methods to be applied during the life cycle of construction projects is explained and a few case studies are presented for clarity on the methods. The framework, offering tools for stakeholders of the construction industry, also aims to help to develop the most appropriate assessment tool, which is based on the priorities of critical conditions. Copyright © 2008 John Wiley & Sons, Ltd and ERP Environment.
Finding factors influencing risk: Comparing Bayesian stochastic search and standard variable selection methods applied to logistic regression models of cases and controls
Authors: Swartz Michael D. , Yu Robert K. , Shete Sanjay 
Published: October 2008

AbstractWhen modeling the risk of a disease, the very act of selecting the factors to be included can heavily impact the results. This study compares the performance of several variable selection techniques applied to logistic regression. We performed realistic simulation studies to compare five methods of variable selection: (1) a confidence interval (CI) approach for significant coefficients, (2) backward selection, (3) forward selection, (4) stepwise selection, and (5) Bayesian stochastic search variable selection (SSVS) using both informed and uniformed priors. We defined our simulated diseases mimicking odds ratios for cancer risk found in the literature for environmental factors, such as smoking; dietary risk factors, such as fiber; genetic risk factors, such as XPD; and interactions. We modeled the distribution of our covariates, including correlation, after the reported empirical distributions of these risk factors. We also used a null data set to calibrate the priors of the Bayesian method and evaluate its sensitivity. Of the standard methods (95 per cent CI, backward, forward, and stepwise selection) the CI approach resulted in the highest average per cent of correct associations and the lowest average per cent of incorrect associations. SSVS with an informed prior had a higher average per cent of correct associations and a lower average per cent of incorrect associations than the CI approach. This study shows that the Bayesian methods offer a way to use prior information to both increase power and decrease false‐positive results when selecting factors to model complex disease risk. Copyright © 2008 John Wiley & Sons, Ltd.
Comparative review of methods for handling drop‐out in longitudinal studies
Authors: Philipson Peter M. , Ho Weang Kee , Henderson Robin 
Published: October 2008

AbstractLongitudinal data analysis is frequently complicated by drop‐out. In this paper we consider several methods for dealing with drop‐out afflicted data. Along with a general comparison, particular attention is paid to the consequences of model misspecification. The purpose of our approach is two‐fold. We first deliberate the form of the drop‐out model and compare two alternatives. Furthermore, the extent to which each method is dependent on its core assumptions is assessed through scenarios where one or more such assumptions are compromised. Second, the extent to which we can identify adequacy of model fit is investigated via recently developed diagnostics. These twin targets are pursued via simulation scenarios and application to a schizophrenia trial of over 500 patients with near 50 per cent drop‐out. Copyright © 2008 John Wiley & Sons, Ltd.
Estimates of clinically useful measures in competing risks survival analysis
Authors: Ambrogi Federico , Biganzoli Elia , Boracchi Patrizia 
Published: October 2008

AbstractCompeting risks occur frequently in follow‐up clinical studies. To assess treatment or covariate effects, measures of clinical impact based on crude cumulative incidence should be considered, such as relative risks or the absolute risk reduction. In this work, transformation models through suitable link functions provide a straightforward approach to obtain point and interval estimates of such measures. An extension of the Klein and Andersen proposal, based on pseudo‐values, is considered. Non‐additive effects were tested by interactions between baseline (spline function on time) and covariates. The methods are applied to the evaluation of the impact of axillary lymph node nanometastases on metastatic relapse of breast cancer patients. Further, a literature data set on prostate cancer was used for illustration. Copyright © 2008 John Wiley & Sons, Ltd.
Genotoxic and oxidative stress‐inducing effects of deltamethrin in the erythrocytes of a freshwater biomarker fish species, Channa punctata Bloch
Authors: Ansari Rizwan A. , Kaur Manpreet , Ahmad Firoz , Rahman Shakilur , Rashid Hina , Islam Fakhrul , Raisuddin Sheikh 
Published: October 2008

AbstractDeltamethrin, an α‐cyano class of pyrethroid insecticide is used in insect pest control and antimalaria programs in several countries including India. Although various toxic manifestations of deltamethrin are reported in mammals, its ecotoxicologic dimensions are not adequately researched in ecologically and commercially important fishes. In this study, we report genotoxic effect of deltamethrin in a biomarker fish Channa punctata (Bloch). Adult fish were exposed to three concentrations of technical grade deltamethrin (0.4, 0.8, and 1.2 μg/L) for 48 and 72 h. Ethyl methane sulfonate was used as a positive control. Fish were analyzed for induction of micronucleus (MN), nuclear abnormalities (NAs), and oxidative stress biomarkers in erythrocytes. Deltamethrin significantly induced MN and NAs accompanied by increased lipid peroxidation. Activity of antioxidant enzyme superoxide dismutase was significantly decreased but an increase was observed in reduced glutathione level after 72 h of exposure. The NAs in exposed fish included blebbed, lobed and notched nuclei, and binucleated erythrocytes. Our findings suggest that oxidative stress may, in part, be contributing to deltamethrin‐induced genotoxic damage to erythrocytes. Although MN induction is a nonspecific biomarker, it may provide an indication of pollution load of deltamethrin in the affected fish population when used as part of suite of other biomarkers. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2009.
Morphological and biochemical changes associated with apoptosis induced by okadaic acid in human amniotic FL cells
Authors: Xing Ming‐luan , Wang Xiao‐feng , Zhu Xin , Zhou Xu‐dong , Xu Li‐hong 
Published: October 2008

AbstractThe marine toxin okadaic acid (OA) is an apoptosis inducer and a tumor promoter. During recent years, extensive studies have demonstrated that OA can induce apoptosis in a wide variety of cell types. In contrast to the relatively longer incubation time or higher treatment concentrations of OA in apoptosis shown previously, relatively lower concentrations (≤100 nM) and shorter time (4 h) were designed in the current study to observe the toxic effects of OA in human amniotic cells (FL cells). The present study was undertaken to determine the morphological and biochemical changes of FL cells induced by OA. Results indicated that externalization of phosphatidylserine, cytoskeletal disruption, DNA strand breaks and decrease of Bcl‐2 protein expression levels as well as increase of PP2A‐A subunit protein were all involved in the apoptosis of FL cells induced by OA. This work not only provided further evidence of apoptosis induced by OA but also suggested that PP2A might play a pivotal role in apoptosis induced by protein phosphatases inhibitors. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2009.
Subchronic lead feeding study in male rats and micropigs
Authors: Smith Duane M. , Mielke Howard W. , Heneghan James B. 
Published: October 2008

AbstractThis study compared the lead uptake from contaminated test soil of known lead concentration with a soluble lead acetate standard, which was considered to be 100% bioavailable. This study also compared the lead bioavailability from this lead‐contaminated soil between rats and micropigs. Harlan Sprague–Dawley rats and Yucatan micropigs were fed lead‐contaminated soil as a 5% (w/w) mixture with their diet. The lead‐contaminated soil was either a specific test soil of known lead concentration (1000 μg/g) or basal low concentration lead soil (∼135 μg/g), which was spiked with lead acetate to match the lead content of the test soil. The effective diet lead concentration was 50 μg Pb/g diet. Results demonstrated that rats reached steady‐state concentrations of blood lead by week 2, whereas micropigs did not reach steady state until week 4. In addition, final blood lead concentrations in micropigs were four‐fold higher than those in rats. In the micropigs, the final blood lead levels in the test soil study group were significantly lower than those in the lead acetate study group, although there was no significant difference between study groups in the rats. Tissue lead concentrations were significantly higher in micropigs than those in the rats, although the diet lead concentrations in both sets of animals were the same. In summary, because of the greater sensitivity in demonstrating higher tissue lead incorporation in micropigs as compared to rats, the micropig is a better animal model for demonstrating the differences in relative lead bioavailability when testing different sources of lead‐contaminated soils. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2009.
Application of a coordinate‐free tensor formalism to the numerical implementation of a material model
Authors: Shutov A.V. , Kreißig R. 
Published: October 2008

AbstractWe analyze a coordinate‐free tensor setting in ℝ3 within the context of the classical tensor analysis. To this end, we formulate in a basis‐free manner the notions of second‐ and fourth‐rank tensors in ℝ3, and corresponding operations on tensors. Among the large number of different approaches to the tensor setting, we give the preference to the convenient ones, concerning the specific needs of computational solid mechanics. We use the well‐known Fréchet derivative to define the derivative of a function with respect to its tensor argument in a natural way. Furthermore, such aspects as the derivative with respect to a symmetric tensor argument and its uniqueness are covered in this paper. For the sake of completeness we present the coordinate representation of tensors and tensor operations. This representation is obtained in a straight‐forward manner from the coordinate‐free one. In particular, we elaborate the computation of the inverse of a fourth‐rank tensor and the inverse of a linear transformation on the space of symmetric second‐rank tensors. The tensor formalism is applied to the analysis of a nonlinear system of differential and algebraic equations governing visoplastic material response. An implicit time‐stepping algorithm is formulated and the numerical treatment of the algorithm is discussed.
Stochastic finite elements: Computational approaches to stochastic partial differential equations
Authors: Matthies H.G. 
Published: October 2008

AbstractUncertainty estimation arises at least implicitly in any kind of modelling of the real world, and it is desirable to actually quantify the uncertainty in probabilistic terms. Here the emphasis is on uncertain systems, where the randomness is assumed spatial. Traditional computational approaches usually use some form of perturbation or Monte Carlo simulation. This is contrasted here with more recent methods based on stochastic Galerkin approximations. Also some approaches to an adaptive uncertainty quantification are pointed out. \abstract{Uncertainty estimation arises at least implicitly in any kind of modelling of the real world, and it is desirable to actually quantify the uncertainty in probabilistic terms. Here the emphasis is on uncertain systems, where the randomness is assumed spatial. Traditional computational approaches usually use some form of perturbation or Monte Carlo simulation. This is contrasted here with more recent methods based on stochastic Galerkin approximations. Also some approaches to an adaptive uncertainty quantification are pointed out.}
Association between polymorphisms of endothelial nitric oxide synthase gene (NOS3) and left posterior wall thickness (LPWT) of the heart in Fabry disease
Authors: Rohard I. , Schaefer E. , Kampmann C. , Beck M. , Gal A. 
Published: October 2008

SummaryFabry disease is an X‐chromosomal storage disorder due to loss‐of‐function mutations of the GLA gene encoding the lysosomal enzyme α‐galactosidase A. Accumulating glycosphingolipid deposits disturb the function of various cells, in particular that of myocytes, arterial smooth‐muscle cells, and vascular endothelium. Hypertrophic cardiomyopathy, for example measured by left posterior wall thickness (LPWT) of the heart, represents a major component of Fabry disease morbidity in adult patients. Endothelium‐derived nitric oxide (eNO), produced by eNO synthase (eNOS), is a key regulator of vessel wall function and cardiovascular homeostasis. We analysed the effect of the polymorphisms c.894G > T (p.Glu298Asp) in exon 7 and the 27 bp tandem repeat (VNTR; allele a: 4 and allele b: 5 repeats) in intron 4 of the NOS3 gene, encoding eNOS, on LPWT of 102 patients with Fabry disease. For the association analysis, the distance of each patient's LPWT value from the cohort‐specific, age‐dependent regression line point (expected values) was used. In the cohort of 46 male patients, LPWT mean value of the group with GG genotype at position c.894 was smaller by 1 mm than that of (GT + TT) (p = 0.058). LPWT of patients with bb was thicker by 1.4 mm than that of (ab + aa) (p = 0.022). In patients with haplotype Ga, a thinner LPWT was seen than in those with Tb (p = 0.006). While no correlation was found between the GLA genotype and LPWT, the difference of 2.44 mm between the relative LPWT mean values of the two extreme NOS3 groups corresponds to the absolute LPWT increase that an average male patient with Fabry disease experiences during about 12 years. These are the first data showing a significant association of non‐GLA‐derived sequence variants with the cardiac phenotype in Fabry disease that may in part explain the great phenotypic variability of the disease.
Treatment of a child diagnosed with Niemann–Pick disease type C with miglustat: A case report in Brazil
Authors: Santos M. L. F. , Raskin S. , Telles D. S. , Löhr Junior A. , Liberalesso P. B. N. , Vieira S. C. , Cordeiro M. L. 
Published: October 2008

SummaryNiemann–Pick disease type C (NPC) is an autosomal recessive neurovisceral lysosomal lipid storage disorder that leads to variable symptoms that include cognitive decline, ataxia, dystonia, cataplexy, vertical supranuclear gaze palsy, and seizures. Currently, there is no specific treatment for NPC other than palliative care. Substrate reduction therapy represents a potential strategy for treating this debilitating neurodegenerative disorder. Miglustat (Zavesca) is a reversible inhibitor of the enzyme glucosylceramide synthase, which catalyses the first step in the biosynthesis of most glycosphingolipids. Miglustat has pharmacokinetic properties that allow it to cross the blood–brain barrier, thus making it a potential therapeutic agent for treating neurological symptoms in NPC patients. We present here a case report of a Brazilian child treated with miglustat. Before treatment, the patient presented with difficulties walking and swallowing, slurred speech, moderate cognitive impairments, ataxia, ptosis, and vertical supranuclear ophthalmoplegia. On a disability scale, the patient obtained a score of 15 before treatment and 8 after treatment. Following 12 months of treatment, the patient remained stable with improvements in speech, ptosis, ophthalmoplegia, ataxia, hypotonia and seizures. The Child Behavior Checklist (CBCL) was used to assess psychopathological, behavioural and social problems before and after treatment. The CBCL showed that indices for depression #Affective and attention problems were all in the normal range following treatment. Thus, for this individual miglustat was an effective, well‐tolerated and efficacious medication for treatment of NPC symptoms. Follow‐up maintenance studies are vital to establish whether both the efficacy and safety of miglustat persist with time.