Multiple Components (multiple + component)

Distribution by Scientific Domains


Selected Abstracts


Immunonutrition support for athletes

NUTRITION REVIEWS, Issue 6 2008
David C Nieman
Multiple components of the immune systems in athletes exhibit transient dysfunction after prolonged, heavy exertion. During this "open window" of impaired immunity, pathogens may gain a foothold, increasing infection risk. Nutritional supplements have been studied as countermeasures to exercise-induced immune changes and infection risk. This review focuses on findings from recent exercise-based studies with macro- and micronutrient supplements, and "advanced" immunonutrition supplements including ,-glucan, curcumin, and quercetin. Results from these studies indicate that immunonutrition supplements have the potential to lessen the magnitude of exercise-induced perturbations in immune function and to reduce the risk of upper respiratory tract infections. [source]


RATES, RIGHTS, AND REGIONAL PLANNING IN THE METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA,

JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 5 2002
Richard Atwater
ABSTRACT: The Metropolitan Water District of Southern California has for more than 70 years shaped the development of an immense urban region. The district's current strategic planning process therefore could have substantial effects on regional water planning and management. The rate restructuring phase of the planning process has produced a multiple component, cost of service based framework. This paper describes that framework as well as some criticisms that have been directed toward it. The rate restructuring was shaped, and for a while stalled, by old disputes among member agencies over rights to water supplied by Metropolitan. That controversy has diverted attention from the resource management implications of the rate structure. This paper presents an alternative future focused approach to regional integrated water resource planning for Southern California based on projections of current trends and anticipation of future events. This discussion raises the question of how regional integrated water resources planning of this sort may proceed, and what role Metropolitan will play in that process. [source]


Deformation Transfer to Multi-Component Objects

COMPUTER GRAPHICS FORUM, Issue 2 2010
Kun Zhou
Abstract We present a simple and effective algorithm to transfer deformation between surface meshes with multiple components. The algorithm automatically computes spatial relationships between components of the target object, builds correspondences between source and target, and finally transfers deformation of the source onto the target while preserving cohesion between the target's components. We demonstrate the versatility of our approach on various complex models. [source]


Molecular characterization of Ciona sperm outer arm dynein reveals multiple components related to outer arm docking complex protein 2

CYTOSKELETON, Issue 10 2006
Akiko Hozumi
Abstract Using proteomic and immunochemical techniques, we have identified the light and intermediate chains (IC) of outer arm dynein from sperm axonemes of the ascidian Cionaintestinalis. Ciona outer arm dynein contains six light chains (LC) including a leucine-rich repeat protein, Tctex1- and Tctex2-related proteins, a protein similar to Drosophila roadblock and two components related to Chlamydomonas LC8. No LC with thioredoxin domains is included in Ciona outer arm dynein. Among the five ICs in Ciona, three are orthologs of those in sea urchin dynein: two are WD-repeat proteins and the third one, unique to metazoan sperm flagella, contains both thioredoxin and nucleoside diphosphate kinase modules. The remaining two Ciona ICs have extensive coiled coil structure and show sequence similarity to outer arm dynein docking complex protein 2 (DC2) that was first identified in Chlamydomonas flagella. We recently identified a third DC2-like protein with coiled coil structure, Ci-Axp66.0 that is also associated in substoichiometric amounts with Ciona outer arm dynein. In addition, Oda5p, a component of an additional complex required for assembly of outer arm dynein in Chlamydomonas flagella, also groups with this family of DC2-like proteins. Thus, the assembly of outer arm dynein onto doublet microtubules involves multiple coiled-coil proteins related to DC2. Cell Motil. Cytoskeleton 2006. © 2006 Wiley-Liss, Inc. [source]


Retinoic acid induces CDK inhibitors and growth arrest specific (Gas) genes in neural crest cells

DEVELOPMENT GROWTH & DIFFERENTIATION, Issue 3 2005
Linping Wang
Retinoic acid (RA), the active metabolite of vitamin A, regulates cellular growth and differentiation during embryonic development. In excess, this vitamin is also highly teratogenic to animals and humans. The neural crest is particularly sensitive to RA, and high levels adversely affect migration, proliferation and cell death. We investigated potential gene targets of RA associated with neural crest proliferation by determining RA-mediated changes in gene expression over time, using microarrays. Statistical analysis of the top ranked RA-regulated genes identified modest changes in multiple genes previously associated with cell cycle control and proliferation including the cyclin-dependent kinase inhibitors Cdkn1a (p21), Cdkn2b (p15INK4b), and Gas3/PMP22. The expression of p21 and p15INK4b contribute to decreased proliferation by blocking cell cycle progression at G1-S. This checkpoint is pivotal to decisions regulating proliferation, apoptosis, or differentiation. We have also confirmed the overexpression of Gas3/PMP22 in RA-treated neural crests, which is associated with cytoskeletal changes and increased apoptosis. Our results suggest that increases in multiple components of diverse regulatory pathways have an overall cumulative effect on cellular decisions. This heterogeneity contributes to the pleiotropic effects of RA, specifically those affecting proliferation and cell death. [source]


Association of components of the metabolic syndrome with the appearance of aggregated red blood cells in the peripheral blood.

DIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 2 2005
An unfavorable hemorheological finding
Abstract Background Components of the metabolic syndrome are associated with low-grade inflammation. This can be accompanied by the synthesis of sticky proteins and erythrocyte aggregation. Methods The degree of erythrocyte aggregation was evaluated by a simple slide test and image analysis along with other markers of the acute-phase response, including the white blood cell count (WBCC), erythrocyte sedimentation rate (ESR), fibrinogen and high sensitivity C-reactive protein (hs-CRP) concentrations. Patients were categorized in four groups according to the absence or presence of 1, 2 and 3 or more components of the metabolic syndrome. Results We examined a total of 1447 individuals (576 women and 871 men) who gave their informed consent for participation. A significant cardiovascular risk factors, age and hemoglobin adjusted correlation was noted between the degree of erythrocyte aggregation and the number of components of the metabolic syndrome (r = 0.17, p < 0.0005). This correlation was better than that observed for clottable fibrinogen (r = 0.13 p < 0.0005), for ESR (r = 0.11 p < 0.0005) or WBCC (r = 0.13 p < 0.0005). A somewhat better correlation was noted for hs-CRP (r = 0.26 p < 0.0005). Conclusions The multiplicity of components of the metabolic syndrome is associated with enhanced erythrocyte aggregation, probably related to the presence of multiple adhesive macromolecules in the peripheral blood. The enhanced aggregation might contribute to capillary slow flow, tissue deoxygenation as well as vasomotor tone changes in the presence of multiple components of this syndrome. Copyright © 2004 John Wiley & Sons, Ltd. [source]


REPRODUCTIVE ISOLATION CAUSED BY NATURAL SELECTION AGAINST IMMIGRANTS FROM DIVERGENT HABITATS

EVOLUTION, Issue 4 2005
Patrik Nosil
Abstract The classification of reproductive isolating barriers laid out by Dobzhansky and Mayr has motivated and structured decades of research on speciation. We argue, however, that this classification is incomplete and that the unique contributions of a major source of reproductive isolation have often been overlooked. Here, we describe reproductive barriers that derive from the reduced survival of immigrants upon reaching foreign habitats that are ecologically divergent from their native habitat. This selection against immigrants reduces encounters and thus mating opportunities between individuals from divergently adapted populations. It also reduces the likelihood that successfully mated immigrant females will survive long enough to produce their hybrid offspring. Thus, natural selection against immigrants results in distinctive elements of premating and postmating reproductive isolation that we hereby dub "immigrant inviability". We quantify the contributions of immigrant inviability to total reproductive isolation by examining study systems where multiple components of reproductive isolation have been measured and demonstrate that these contributions are frequently greater than those of traditionally recognized reproductive barriers. The relevance of immigrant inviability is further illustrated by a consideration of population-genetic theory, a review of selection against immigrant alleles in hybrid zone studies, and an examination of its participation in feedback loops that influence the evolution of additional reproductive barriers. Because some degree of immigrant inviability will commonly exist between populations that exhibit adaptive ecological divergence, we emphasize that these barriers play critical roles in ecological modes of speciation. We hope that the formal recognition of immigrant inviability and our demonstration of its evolutionary importance will stimulate more explicit empirical studies of its contributions to speciation. [source]


Green fluorescent protein , a bright idea for the study of bacterial protein localization

FEMS MICROBIOLOGY LETTERS, Issue 1 2001
Gregory J Phillips
Abstract Use of the green fluorescent protein (GFP) of Aequorea victoria as a reporter for protein and DNA localization has provided sensitive, new approaches for studying the organization of the bacterial cell, leading to new insights into diverse cellular processes. GFP has many characteristics that make it useful for localization studies in bacteria, primarily its ability to fluoresce when fused to target polypeptides without the addition of exogenously added substrates. As an alternative to immunofluorescence microscopy, the expression of gfp gene fusions has been used to probe the function of cellular components fundamental for DNA replication, translation, protein export, and signal transduction, that heretofore have been difficult to study in living cells. Moreover, protein and DNA localization can now be monitored in real time, revealing that several proteins important for cell division, development and sporulation are dynamically localized throughout the cell cycle. The use of additional GFP variants that permit the labeling of multiple components within the same cell, and the use of GFP for genetic screens, should continue to make this a valuable tool for addressing complex questions about the bacterial cell. [source]


Developmental, metabolic and immunological costs of flea infestation in the common vole

FUNCTIONAL ECOLOGY, Issue 6 2008
Godefroy Devevey
Summary 1Parasites use resources from their hosts, which can indirectly affect a number of host functions because of trade-offs in resource allocation. In order to get a comprehensive view of the costs imposed by blood sucking parasites to their hosts, it is important to monitor multiple components of the development and physiology of parasitized hosts over long time periods. 2The effect of infestation by fleas on body mass, body length growth, haematocrit, resistance to oxidative stress, resting metabolic rate and humoral immune response were experimentally evaluated. During a 3-month period, male common voles, Microtus arvalis, were either parasitized by rat fleas (Nosopsyllus fasciatus), which are naturally occurring generalist ectoparasites of voles, or reared without fleas. Then voles were challenged twice by injecting Keyhole Limpet Haemocyanin (KLH) to assess whether the presence of fleas affects the ability of voles to produce antibodies against a novel antigen. During the immune challenge we measured the evolution of body mass, haematocrit, resistance to oxidative stress and antibody production. 3Flea infestation negatively influenced the growth of voles. Moreover, parasitized voles had reduced haematocrit, higher resting metabolic rate and lower production of antibodies against the KLH. Resistance to oxidative stress was not influenced by the presence of fleas. 4During the immune challenge with KLH, body mass decreased in both groups, while the resistance to oxidative stress remained stable. In contrast, the haematocrit decreased only in parasitized voles. 5Our experiment shows that infestation by a haematophageous parasite negatively affects multiple traits like growth, energy consumption and immune response. Fleas may severely reduce the survival probability and reproductive success of their host in natural conditions. [source]


ARC protects rat cardiomyocytes against oxidative stress through inhibition of caspase-2 mediated mitochondrial pathway

JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 2 2006
Yi-Qiang Zhang
Abstract Apoptosis repressor with a CARD domain (ARC) has been demonstrated to protect heart cells against ischemia/reperfusion (I/R) injury. In this study, we investigated the mechanism by which ARC protects heart cells against oxidative stress. We monitored the extent of apoptosis and activity of multiple components of the intrinsic apoptotic pathway in rat cardiac myoblast cell line H9c2 with either reduced or increased expression of ARC during oxidative stress. Overexpression of ARC-inhibited oxidative stress-induced caspase-2/3 activation, cytochrome c release, and translocation of Bax to mitochondria. Furthermore, phosphorylation of ARC at threonine 149 was found to be critical to its function. ARC containing a T149A mutation failed to translocate to mitochondria, did not inhibit caspase-2 activation, and had a dominant negative effect against the protective effect of endogenous ARC during oxidative stress. In addition, wild-type ARC but not the T149A mutant inhibited cell death induced by overexpression of caspase-2. Using a yeast two-hybrid (YTH) screening approach and co-immunoprecipitation (Co-IP), we found that protein phosphatase 2C (PP2C) interacted with ARC and that PP2C mediated-dephosphorylation of ARC inhibited its anti-apoptotic activity. Eliminating either the N-terminal CARD domain or the C-terminal P/E domain also abolished the anti-apoptotic function of ARC, suggesting that full-length ARC is required for its apoptotic inhibition. These results indicate that ARC plays an important role in protection of H9c2 cells against oxidative stress-induced apoptosis by phosphorylation-dependent suppression of the mitochondria-mediated intrinsic pathway, partially initiated through the activation of caspase-2. J. Cell. Biochem. 99: 575,588, 2006. © 2006 Wiley-Liss, Inc. [source]


Crystallization pathways and kinetics of carbamazepine,nicotinamide cocrystals from the amorphous state by in situ thermomicroscopy, spectroscopy, and calorimetry studies

JOURNAL OF PHARMACEUTICAL SCIENCES, Issue 5 2007
K. Seefeldt
Abstract The work presented here was motivated by the premise that the amorphous state serves as a medium to study cocrystal formation. The molecular mobility inherent to amorphous phases can lead to molecular associations between different components such that a single crystalline phase of multiple components or cocrystal is formed. Cocrystallization pathways and kinetics were investigated from amorphous equimolar phases of carbamazepine and nicotinamide using hot-stage polarized microscopy (HSPM), hot-stage Raman microscopy (HSRM), differential scanning calorimetry (DSC), and X-ray powder diffraction (XRPD). Nonisothermal studies revealed that amorphous phases generate cocrystals and that thermal history affects crystallization pathways in significant ways. Two different pathways to cocrystal formation from the amorphous phase were identified: (1) at low heating rates (3°C/min) a metastable cocrystalline phase initially nucleates and transforms to the more stable cocrystalline phase of CBZ,NCT, and (2) at higher heating rates (10°C/min) individual components crystallize, then melt and the stable cocrystalline phase nucleates and grows from the melt. Isothermal studies above the Tg of the amorphous equimolar phase also confirm the nucleation of a metastable cocrystalline phase from the amorphous state followed by a solid phase mediated transformation to the stable cocrystalline phase. Cocrystallization kinetics were measured by image analysis and by thermal analysis from small samples and are described by the Avrami,Erofeev model. These findings have important implications for the use of amorphous phases in the discovery of cocrystals and to determine the propensity of cocrystallization from process-induced amorphization. © 2007 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 96: 1147,1158, 2007 [source]


A Sonic Hedgehog (SH) Fusion Protein Corrects Multifocal Defects In Experimental Diabetic Neuropathy

JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 3 2000
Dr Tomlinson
Diabetic neuropathy develops from defective interactions between nerve axons and other cells in the endoneurium; such interactions are influenced in development by hedgehog proteins. This study explored the possibility that this might be maintained in the adult and form a basis for therapy in diabetic neuropathies. Streptozotocin-diabetic rats were treated (final 5 weeks of 10 weeks diabetes) with a SH-IgG fusion protein (either 0.3mg/kg or 3.0mg/kg s.c. 3 times per week); control diabetic and non-diabetic rats received vehicle. Conduction velocity (MNCV, SNCV) data and sciatic nerve levels of nerve growth factor (NGF) and neuropeptide Y (NPY) are presented below. Diabetes caused significant (p < 0.05 by ANOVA with SNK tests) reductions in all variables and treatment with SH-IgG either attenuated or prevented (p < 0.05) these reductions. Since it is well-established that the conduction deficits are unrelated to neurotrophic deficits (NGF depletion) and that NPY depletion derives from a neurotrophic defect distinct from NGF, this treatment clearly acts at multiple components of the aetiology of diabetic neuropathy. [source]


Reconsidering Styles of Regulatory Enforcement: Patterns in Danish Agro-Environmental Inspection

LAW & POLICY, Issue 2 2000
Peter May
This study addresses enforcement styles of regulatory inspectors, based on an examination of the municipal enforcement of agro-environmental policies in Denmark. Our findings make three contributions to the regulatory literature. One contribution is to add empirical support for theorizing about inspectors' enforcement styles as consisting of multiple components, rather than a single continuum. We show that inspectors' enforcement styles comprise the degree of formalism and the degree of coercion that they exercise when carrying out inspections. A second contribution is in showing the relationship of different types of enforcement styles to the two underlying dimensions of the concept. A third contribution is an examination of the ways in which inspectors' enforcement styles relate to their enforcement actions. The consistency of our findings with those of other studies suggests that the dimensions and types of inspectors' enforcement styles that we observed in Denmark can be generalized to other settings. [source]


Attentional dysfunction of chronic schizophrenia: No association with long-term institutionalization

PSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 4 2002
LUIGI CREMASCO MD
Abstract Attentional processes play a central role in information selection, which is impaired in schizophrenic patients. In the present study, we attempted to characterize the attentional performance of chronic schizophrenics using a computerized assessment of the multiple components of attentional function. Two comparable samples, consisting, respectively, of out-patients and in-patients, were tested in order to assess the effect of chronic institutionalization. Twenty-four subjects (half in-patients and half out-patients) fulfillling DSM-IV criteria for schizophrenia were examined with a standard computerized battery for the assessment of attention, namely Testbatterie zur Aufmerksamkeitsprufung (TAP). Both groups were impaired on all measures of attentional processing (in terms of both reaction times and number of errors). There were no significant differences in attentional performance between in- and out-patients. In conclusion, the present findings confirm the presence of pervasive attentional dysfunction in chronic schizophrenia; the lack of significant differences in performance between in- and out-patients supports the hypothesis that the cognitive deficits are inherently associated with the illness and cannot be attributed to environmental/social factors. [source]


Urban pattern and land cover variation in the greater Toronto area

THE CANADIAN GEOGRAPHER/LE GEOGRAPHE CANADIEN, Issue 1 2007
TENLEY CONWAY
Recent epistemological shifts in environmental geography have created a space to consider the interactions between ecological and urban systems more seriously. While openness to thinking about urban ecosystems has increased in recent years, there remain fundamental gaps in our knowledge. For example, recent research has examined the impact of urban,rural gradients on ecological conditions, but major voids exist regarding the relationship between urban development patterns and land cover heterogeneity, particularly for new forms of urbanization. This article attempts to address some of these gaps by examining the relationship between urban pattern and land cover in the greater Toronto area (GTA). In particular, measures of urban pattern that reflect aspects of development density, grain and function, as well as socio-economic characteristics, are systematically analyzed in relation to land cover heterogeneity. The regression analysis shows that multiple components of urban development pattern and socio-economic conditions are correlated with vegetated land covers, while urban density variables are not related. These results indicate more detailed representations of urban pattern should be incorporated into future human,environmental interaction studies in cities. Les changements épistémologiques récents en géographie environnementale ont créé un espace dans lequel les interactions entre les systèmes écologiques et urbains sont considérées plus sérieusement. Par contre, bien qu'il existe depuis quelques temps plus de possibilités pour réfléchir aux écosystèmes urbains, des questions fondamentales subsistent. Par exemple, des recherches récentes se sont penchées sur l'impact des gradients urbain-ruraux sur les conditions écologiques. Toutefois, des lacunes importantes demeurent en ce qui concerne les liens entre les modèles de développement urbain et l'hétérogénéité de la couverture des sols, notamment en ce qui a trait aux nouvelles formes d'urbanisation. Cet article aborde certaines de ces lacunes en examinant les liens entre le modèle urbain et la couverture des sols dans la région du Grand Toronto (RGT). En particulier, des mesures du modèle urbain reflétant des aspects de la densité de développement, la texture et la fonction, ainsi que les caractéristiques socio-économiques sont systématiquement analysées par rapport à l'hétérogénéité de la couverture des sols. L'analyse de régression montre une corrélation entre plusieurs composantes du modèle de développement urbain et des conditions socio-économiques, d'une part, et le type de couverture végétale des sols, d'autre part. Les variables utilisées pour la densité urbaine ne sont pas reliées. Ces résultats font ressortir que des représentations plus détaillées du modèle urbain devraient être intégrées aux études ultérieures consacrées aux interactions humain-environnement en milieu urbain. [source]


SIPK signaling controls multiple components of harpin-induced cell death in tobacco

THE PLANT JOURNAL, Issue 3 2005
Marcus A. Samuel
Summary Harpin from Pseudomonas syringae pv. phaseolicola (HrpZ) elicits a rapid cell death response in tobacco plants. Multiple signaling components, including mitogen-activated protein kinase (MAPK), reactive oxygen species (ROS) and salicylic acid (SA), have been reported to be involved in this cell death process, but the interaction between these molecules is poorly understood. Here we show through utilizing plants manipulated in SIPK expression levels that lack of SIPK results in increased sensitivity to harpin with concomitant accumulation of higher levels of ROS. Conversely, SIPK-overexpressing plants show reduced sensitivity to harpin relative to wild-type plants, and display reduced ROS accumulation. Harpin-induced cell death was found to be conditional on the ability of the plant to accumulate SA, whereas harpin induction of MAPK activation and ROS accumulation are not. However, harpin-induced ROS accumulation is required for activation of SIPK and wound-induced protein kinase. Transcriptional profiling revealed that suppression of SIPK signaling also affects early expression of a range of pathogen- and stress-responsive genes during harpin challenge. [source]


Antioxidant capacity of human milk and its association with vitamins A and E and fatty acid composition

ACTA PAEDIATRICA, Issue 11 2009
A Tijerina-Sáenz
Abstract Aim:, The antioxidant capacity of human milk reflects the presence and activity of multiple components, which prevent oxidative rancidity. The aim of this study was to use the Oxygen Radical Absorbance Capacity assay to assess human milk antioxidant capacity and find correlations with milk components. Methods:, Milk samples collected from 60 breastfeeding women at 1 month postpartum were assayed for antioxidant capacity, vitamins E and A, and fatty acids. Potential statistical relationships of concentrations of vitamins A and E and polyunsaturated fatty acids on the antioxidant capacity of human milk were determined. Results:, Human milk antioxidant capacity was positively attributed to ,-tocopherol concentration (, < 0.05). The vitamin A concentration did not significantly contribute to milk antioxidant capacity, but was correlated to milk ,-tocopherol concentration (r = 0.587; , < 0.001). There was no evidence of an inverse relationship between polyunsaturated fatty acids concentration and the antioxidant capacity value of milk. Conclusion:, This study shows that ,-tocopherol is an important contributor to the oxidative stability of human milk. Moreover, there was no evidence obtained to show that women who have high levels of milk polyunsaturated fatty acids are predisposed to lower milk antioxidant capacity. [source]