Various Components (various + component)

Distribution by Scientific Domains
Distribution within Medical Sciences


Selected Abstracts


Various components of the insulin-like growth factor system in tumor tissue, cerebrospinal fluid and peripheral blood of pediatric medulloblastoma and ependymoma patients

INTERNATIONAL JOURNAL OF CANCER, Issue 3 2008
Judith M. de Bont
Abstract The insulin-like growth factor (IGF) system plays an important role in neuronal development and may contribute to the development of brain tumors. In this study, we studied mRNA expression levels of IGFs, insulin-like growth factor binding proteins (IGFBPs) and insulin-like growth factor receptors (IGFRs) in 27 pediatric medulloblastomas, 13 pediatric ependymomas and 5 control cerebella. Compared to normal cerebellum, mRNA levels of IGFBP-2 and IGFBP-3 were significantly increased in medulloblastomas and ependymomas. IGFBP-2 expression was indicative of poor prognosis in medulloblastomas, whereas IGFBP-3 mRNA levels were especially high in anaplastic ependymomas. IGFBP-5 and IGF-II mRNA levels were significantly increased in ependymomas compared to control cerebellum. Protein expression levels of IGFs and IGFBPs were analyzed in the cerebrospinal fluid (CSF) of 16 medulloblastoma, 4 ependymoma and 23 control patients by radioimmuno assay to determine whether they could be used as markers for residual disease after surgery. No aberrant CSF protein expression levels were found for ependymoma patients. In medulloblastoma patients, the IGFBP-3 protein levels were significantly higher than in ependymoma patients and controls. Moreover, enhanced levels of proteolytic fragments of IGFBP-3 were found in the CSF of medulloblastoma patients, being in concordance with a significantly increased IGFBP-3 proteolytic activity in the CSF of these patients. In conclusion, our data suggest that the IGF system is of importance in pediatric medulloblastomas and ependymomas. Larger studies should be conducted to validate the predictive values of the levels of intact IGFBP-3 and proteolytic fragments in CSF in the follow-up of medulloblastomas. © 2008 Wiley-Liss, Inc. [source]


Coordinating components in middleware systems

CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 13 2003
Matthias Radestock
Abstract Configuration and coordination are central issues in the design and implementation of middleware systems and are one of the reasons why building such systems is more complex than constructing stand-alone sequential programs. Through configuration, the structure of the system is established,which elements it contains, where they are located and how they are interconnected. Coordination is concerned with the interaction of the various components,when an interaction takes place, which parties are involved, what protocols are followed. Its purpose is to coordinate the behaviour of the various components to meet the overall system specification. The open and adaptive nature of middleware systems makes the task of configuration and coordination particularly challenging. We propose a model that can operate in such an environment and enables the dynamic integration and coordination of components by observing and coercing their behaviour through the interception of the messages exchanged between them. Copyright © 2003 John Wiley & Sons, Ltd. [source]


Role of orexins in the hypothalamic-pituitary-ovarian relationships

ACTA PHYSIOLOGICA, Issue 3 2010
P. Silveyra
Abstract Appropriate nutritional and vigilance states are needed for reproduction. In previous works, we described the influence of the hormonal milieu of proestrus on the orexinergic system and we found that orexin receptor 1 expression in the hypothalamus, but not other neural areas, and the adenohypophysis was under the influence of oestradiol and the time of the day. Information from the sexual hormonal milieu of proestrous afternoon impacts on various components of the orexinergic system and alertness on this particular night of proestrus would be of importance for successful reproduction. In this review, we summarize the available experimental data supporting the participation of orexins in the hypothalamic-pituitary-ovarian relationships. All together, these results suggest a role of the orexinergic system as an integrative link among vital functions such as reproduction, food intake, alertness and the inner biological clock. [source]


Surge Capacity for Healthcare Systems: A Conceptual Framework

ACADEMIC EMERGENCY MEDICINE, Issue 11 2006
Amy Kaji MD
This report reflects the proceedings of a breakout session, "Surge Capacity: Defining Concepts," at the 2006 Academic Emergency Medicine Consensus Conference, "Science of Surge Capacity." Although there are several general descriptions of surge capacity in the literature, there is no universally accepted standard definition specifying the various components. Thus, the objectives of this breakout session were to better delineate the components of surge capacity and to outline the key considerations when planning for surge capacity. Participants were from diverse backgrounds and included academic and community emergency physicians, economists, hospital administrators, and experts in mathematical modeling. Three essential components of surge capacity were identified: staff, stuff, and structure. The focus on enhancing surge capacity during a catastrophic event will be to increase patient-care capacity, rather than on increasing things, such as beds and medical supplies. Although there are similarities between daily surge and disaster surge, during a disaster, the goal shifts from the day-to-day operational focus on optimizing outcomes for the individual patient to optimizing those for a population. Other key considerations in defining surge capacity include psychosocial behavioral issues, convergent volunteerism, the need for special expertise and supplies, development of a standard of care appropriate for a specific situation, and standardization of a universal metric for surge capacity. [source]


Effect of Perilesional Injections of PEG-Interleukin-2 on Basal Cell Carcinoma

DERMATOLOGIC SURGERY, Issue 11 2000
Baruch Kaplan MD
Background: Multiple modalities are available for the treatment of basal cell carcinoma (BCC). The most commonly used modalities include simple excision, Mohs micrographic surgery, curettage and electrodessication, cryosurgery, and irradiation therapy. Interleukin-2 (IL-2) is a cytokine produced chiefly by activated T lymphocytes and has effects on various components of the immune system. Until now the primary clinical use of IL-2 has been in advanced stages of metastatic melanoma and renal cell carcinoma. Systemic administration of IL-2 is known to cause significant toxicity. Objective: The objective of this study was to evaluate the therapeutic efficacy and safety of perilesional PEG-IL-2 injections in patients with BCC in an open label, uncontrolled pilot study. Methods: Patients with histologically confirmed primary BCC over 18 years of age were included in the study. Lesions were treated by injecting a total volume of 0.5 cc of IL-2 in a radial fashion in the subcutaneous tissue. Injection dosages ranged from 3000 to 1,200,000 IU in one to four weekly dosages. A total of 12 tumors were treated in eight patients. Results: Overall response rates were as follows: complete response in 8 of 12 treated tumors (66.6% cure rate), partial response in 3 of 12 injected tumors (25% partial response rate), stable disease with no improvement in 1 treatment site (8.4%). Side effects included local pain, swelling, and erythema, and in one patient flulike symptoms. There were no significant changes of blood tests as compared to baseline levels. Conclusions: The therapeutic response induced by perilesional PEG-IL-2 injections was found to be an encouraging, safe, and well-tolerated treatment of BCC. Further studies including a larger patient population and long-term follow-up are necessary in order to substantiate these findings. [source]


Prediction of cardiovascular and total mortality in Chinese type 2 diabetic patients by the WHO definition for the metabolic syndrome

DIABETES OBESITY & METABOLISM, Issue 1 2006
G. T.-C.
Aim:, The aim of this study is to investigate the prevalence of metabolic syndrome (MES) in type 2 diabetic patients and the predictive values of the World Health Organization (WHO) and National Cholesterol Education Programme (NCEP) definitions and the individual components of the MES on total and cardiovascular mortality. Methods:, A prospective analysis of a consecutive cohort of 5202 Chinese type 2 diabetic patients recruited between July 1994 and April 2001. Results:, The prevalence of the MES was 49.2,58.1% depending on the use of various criteria. There were 189 deaths (men: 100 and women: 89) in these 5205 patients during a median (interquartile range) follow-up period of 2.1 (0.3,3.6 years). Of these, 164 (87%) were classified as cardiovascular deaths. Using the NCEP criterion, patients with MES had a death rate similar to those without (3.51 vs. 3.85%). By contrast, based on the WHO criteria, patients with MES had a higher mortality rate than those without (4.3 vs. 2.4%, p = 0.002). Compared to patients with neither NCEP- nor WHO-defined MES, only the group with MES defined by the WHO, but not NCEP, criterion had significantly higher mortality rate (2.6 vs. 6.8%, p < 0.001). Using Cox regression analysis, only age, duration of diabetes and smoking were identified as independent factors for cardiovascular or total death. Among the various components of MES, hypertension, low BMI and albuminuria were the key predictors for these adverse events. Conclusions:, In Chinese type 2 diabetic patients, the WHO criterion has a better discriminative power over the NCEP criterion for predicting death. Among the various components of the MES defined either by WHO or NCEP, hypertension, albuminuria and low BMI were the main predictors of cardiovascular and total mortality. [source]


Diabetes control and complications: the role of glycated haemoglobin, 25 years on

DIABETIC MEDICINE, Issue 7 2004
S. L. Jeffcoate
Abstract The long-term complications of diabetes have major consequences for individual subjects and growing healthcare delivery and cost implications for society. Evidence for the benefits of good glycaemic control, as monitored by glycated haemoglobin measurements, has been developed in the 25 years since they were introduced to the point where HbA1c assays play central roles in patient management, clinical guidance and audit, and clinical trial design. In this review this evidence is examined and three classes of uncertainty identified that diminish confidence in the effectiveness of these roles for HbA1c. 1Analytical variability between different methods for HbA1c has restricted the application of clinical targets and this problem has recently been addressed by reference method standardization. There are two approaches to this which result in different HbA1c values and this discrepancy needs to be resolved. 2Biological variability in HbA1c values between individuals also restricts its predictive role when applied to populations. The correlations between HbA1c measurements and various components of glycaemia (overall, fasting, postprandial) are still uncertain and differences in protein glycation and de-glycation are greater between subjects than often thought. The influence of variability in erythrocyte life span is an area where research is needed, especially in diabetic subjects. 3Clinical variability is the most important and complex area of uncertainty. A predictive link between HbA1c and clinical outcomes is not as clear-cut as often stated. The correlation with the development of microvascular disease is well established in Type 1 diabetes, but in Type 2 subjects (90% of those with diabetes) the evidence that HbA1c monitoring is of value in predicting or preventing macrovascular disease is not strong, although it is the major cause of morbidity and early death in this group. It is recommended that, as a matter of urgency, these issues be examined, particularly within the context of self-care in diabetes. Diabet. Med. **, ***,*** (2003) [source]


From episcopal conception to monastic compilation: Hemming's Cartulary in context

EARLY MEDIEVAL EUROPE, Issue 3 2002
Francesca Tinti
This article examines the structure and the contents of the late eleventh century Worcester cartulary which forms the second part of London, British Library, Cotton Tiberius A. XIII. Its sections are analysed and checked against the explanatory statements on the composition of the libellus provided by Hemming in his Enucleatio. This essay then contextualizes the composition of the cartulary through an analysis of its various components. Particular attention is paid to the development of the monastic community of Worcester in the late eleventh century and the ways in which the manuscript seems to reflect their acquisition of a specific and distinctive identity. The development, therefore, of their relationship with the bishop of Worcester is especially significant. The evidence provided by the cartulary suggests that, by the time the Norman Samson succeeded Bishop Wulfstan II in 1096, the monks' attitude towards their bishop had noticeably changed from the time when Wulfstan had first suggested the cartulary's composition. [source]


Polygenic Control of Idiopathic Generalized Epilepsy Phenotypes in the Genetic Absence Rats from Strasbourg (GAERS)

EPILEPSIA, Issue 4 2004
Gabrielle Rudolf
Summary: Purpose: Generalized nonconvulsive absence seizures are characterized by the occurrence of synchronous and bilateral spike-and-wave discharges (SWDs) on electroencephalographic recordings, concomitant with behavioral arrest. The GAERS (genetic absence rats from Strasbourg) strain, a well-characterized inbred model for idiopathic generalized epilepsy, spontaneously develops EEG paroxysms that resemble those of typical absence seizures. The purpose of this study was to investigate the genetic control of SWD variables by using a combination of genetic analyses and electrophysiological measurements in an experimental cross derived from GAERS and Brown Norway (BN) rats. Methods: SWD subphenotypes were quantified on EEG recordings performed at both 3 and 6 months in a cohort of 118 GAERS × BN F2 animals. A genome-wide scan of the F2 progenies was carried out with 146 microsatellite markers that were used to test each marker locus for evidence of genetic linkage to the SWD quantitative traits. Results: We identified three quantitative trait loci (QTLs) in chromosomes 4, 7, and 8 controlling specific SWD variables in the cross, including frequency, amplitude, and severity of SWDs. Age was a major factor influencing the detection of genetic linkage to the various components of the SWDs. Conclusions: The identification of these QTLs demonstrates the polygenic control of SWDs in the GAERS strain. Genetic linkages to specific SWD features underline the complex mechanisms contributing to SWD development in idiopathic generalized epilepsy. [source]


Differential targeting of components of the dystrophin complex to the postsynaptic membrane

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2001
Sophie Marchand
Abstract Accumulating evidence points to the participation of dystroglycan in the clustering of nicotinic acetylcholine receptors at the neuromuscular junction [Côtéet al.. (1999) Nature Genet., 3, 338,342]. Dystroglycan is part of a multimolecular complex, either associated with dystrophin (the dystrophin-associated protein complex) at the sarcolemma or with utrophin (the utrophin-associated protein complex) at the neuromuscular junction. Understanding the assembly of this complex at the developing synapse led us to investigate, in Torpedo electrocyte, the intracellular routing and the targeting of several of its components, including dystroglycan, syntrophin, dystrophin and dystrobrevin. We previously demonstrated that acetylcholine receptors and rapsyn, the 43-kDa receptor-associated protein at the synapse, are cotargeted to the postsynaptic membrane via the exocytic pathway [Marchand et al.. (2000) J. Neurosci., 20, 521,528]. Using cell fractionation, immunopurification and immuno-electron microscope techniques, we show that ,-dystroglycan, an integral glycoprotein that constitutes the core of the dystrophin-associated protein complex localized at the innervated membrane, is transported together with acetylcholine receptor and rapsyn in post-Golgi vesicles en route to the postsynaptic membrane. Syntrophin, a peripheral cytoplasmic protein of the complex, associates initially with these exocytic vesicles. Conversely, dystrophin and dystrobrevin were absent from these post-Golgi vesicles and associate directly with the postsynaptic membrane. This study provides the first evidence for a separate targeting of the various components of the dystrophin-associated protein complex and a step-by-step assembly at the postsynaptic membrane. [source]


Seasonal variation in rod recapture rates indicates differential exploitation of Atlantic salmon, Salmo salar, stock components

FISHERIES MANAGEMENT & ECOLOGY, Issue 3 2007
J. L. THORLEY
Abstract, Differential exploitation of the various components of a fish stock can adversely affect the diversity, abundance and long-term survival of the entire stock. Many anadromous salmonid stocks exhibit a seasonal structuring of their run-timing that allows fisheries managers to map monthly rod catches onto stock components. To estimate the rod exploitation levels of the various run-timing groups, fishing guides on the River Spey, Scotland, floy-tagged 786 rod-caught and released Atlantic salmon, Salmo salar L., between 2000 and 2002 and recorded recaptures. Whereas 25% of the fish tagged early in March were recaptured, only 2% of those tagged early in June were caught a second time. Exploitation is biased towards the early-running stock components which current assessments show to be least abundant. Management of Atlantic salmon based on an average exploitation rate is inappropriate. [source]


In,uence of drying methods on the essential oil content and composition of Roman chamomile

FLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2004
R. Omidbaigi
Abstract The ,owers of Roman chamomile (Chamaemelum nobile L. All. var. ,ora plena) cultivated in Iran were dried by three different drying methods of sun-drying, shade-drying and oven-drying at 40 °C. The essential oils of every treatment were obtained by hydrodistillation of the ,owers, and were analysed by GC and GC,MS. The oil content of the shade-dried ,owers was the largest (1.9% w/w) compared to sun-drying (0.4% w/w) and oven-drying at 40 °C (0.9% w/w). Drying methods had no effect on the number of chemical components of the essential oil, as 14 components were identi,ed in the oil of every drying method. The major components were isobutyl angelate, 2-methyl butyl angelate, propyl tiglate, isoamyl angelate and 3-methylbutyl isobutyrate. However, the drying method had a signi,cant effect on the proportion of the various components. Copyright © 2004 John Wiley & Sons, Ltd. [source]


Functional Chromium Wheel-Based Hybrid Organic,Inorganic Materials for Dielectric Applications

ADVANCED FUNCTIONAL MATERIALS, Issue 20 2009
Vito Di Noto
Abstract The first example of organic,inorganic hybrid materials based on the embedding of a chromium,nickel wheel cluster {[(n-C3H7)2NH2]- [Cr7NiF8(O2C4H5)16]} (Cr7Ni) into poly(methyl methacrylate) (PMMA) and the characterization of the dielectric properties of the obtained material is described. By an optimized copolymerization of the methacrylate-functionalized chromium,nickel wheel with methyl methacrylate in a cluster/monomer 1:200 molar mixture, a homogeneous hybrid material CrNi_MMA200 is obtained. The electrical responses of the non-doped PMMA and of the hybrid material were studied by broadband dielectric spectroscopy (BDS) from 0.01,Hz to 10,MHz and over the temperature range of 5,115,°C. The permittivity profiles reveal two relaxation peaks in the materials, which correspond to the , and , relaxation modes of the PMMA matrix. The position of these modes shifts toward higher frequencies as temperature increases. BDS is a powerful tool revealing the intimate miscibility of the various components of the hybrid material, thus indicating that, on a molecular scale, the material proposed is a homogeneous system. Finally, a value of the dielectric constant of 2.9 at 25,°C and 1,kHz is determined. This value is noticeably lower than the value of 3.2 obtained for pristine PMMA prepared following the same synthesis protocol. Thus, these results classify the hybrid CrNi_MMA200 as an appealing starting material for the development of dielectric polymeric layers for the development of innovative capacitors, transistors, and other microelectronic devices. The vibrational properties of the hybrid materials are investigated by Fourier-transform infrared (FT-IR) and Raman spectroscopy, whereas the thermal behavior is analyzed by thermogravimetric analysis (TGA). Swelling experiments are used to qualitatively evaluate the crosslinking density of the hybrid materials. The integrity of the wheels once embedded in the macromolecular backbone is confirmed by extended X-ray absorption fine structure (EXAFS) and electron spin resonance (EPR) spectroscopic measurements. [source]


Elders assessment of an evolving model of oral health

GERODONTOLOGY, Issue 4 2007
Mario A Brondani
Objectives:, To evaluate qualitatively a model of oral health through focus groups among elders. Methods:, The participants (30 women and 12 men; mean age: 75 years) attended one of six focus groups to discuss the relevance of the model to their oral health-related beliefs and experiences, and transcripts of the narratives were analysed systematically for the components, associations and recommendations emerging from the discussions. Results:, The groups confirmed the relevance of the original components of the model with minor modifications, but felt that for completeness it required four additional components: diet; economic priorities; personal expectations; and health values and beliefs. They recommended that the negative connotations of limited activity, impairment and restricted participation were modified with the positive terms activity and participation, and they suggested that ellipses rather than concentric circles more aptly illustrate the dynamic and overlapping importance of the various components in the model. Conclusion:, The original model required additional components and graphic representation to accommodate all of the experiences and beliefs relating to the oral health of the elders who participated in this qualitative study. [source]


Ground Water Sustainability: Methodology and Application to the North China Plain

GROUND WATER, Issue 6 2008
Jie Liu
This article analyzes part of a ground water flow system in the North China Plain (NCP) subject to severe overexploitation and rapid depletion. A transient ground water flow model was constructed and calibrated to quantify the changes in the flow system since the predevelopment 1950s. The flow model was then used in conjunction with an optimization code to determine optimal pumping schemes that improve ground water management practices. Finally, two management scenarios, namely, urbanization and the South-to-North Water Transfer Project, were evaluated for their potential impacts on the ground water resources in the study area. Although this study focuses on the NCP, it illustrates a general modeling framework for analyzing the sustainability, or the lack thereof, of ground water flow systems driven by similar hydrogeologic and economic conditions. The numerical simulation is capable of quantifying the various components of the overall flow budget and evaluating the impacts of different management scenarios. The optimization modeling allows the determination of the maximum "sustainable pumping" that satisfies a series of prescribed constraints. It can also be used to minimize the economic costs associated with ground water development and management. Furthermore, since the NCP is one of the most water scarce and economically active regions in the world, the conclusions and insights from this study are of general interest and international significance. [source]


Consolidation of CS and US representations in associative fear conditioning

HIPPOCAMPUS, Issue 5 2004
Paul W. Frankland
Abstract Much attention has been paid to the associative processes that are necessary to fuse together representations of the various components of an episodic memory. In the present study, we focus on the processes involved in the formation of lasting representations of the individual components that make up a fear-conditioning episode. In one-trial contextual fear conditioning experiments, weak conditioning to context occurs if the shock is delivered immediately following placement of the animal in a novel conditioning apparatus, a phenomenon known as the immediate shock deficit. We show that the immediate shock deficit in mice may be alleviated by pre-exposure to either the context or shock. In using this approach to temporally dissect a contextual fear-conditioning task into its constituent representational and associative processes, we are able to examine directly the processes that are important for formation of lasting representations of the context conditioned stimulus (CS) or unconditioned stimulus (US). Our data indicate that the formation of a lasting representation of the context or shock engages protein synthesis-dependent processes. Furthermore, genetic disruption of cAMP-responsive element binding protein (CREB), a transcription factor that regulates the synthesis of new proteins required for long-term memory, disrupts the formation of lasting context memories. We go on to show that the stress hormone epinephrine modulates the consolidation of a context memory, and reverses consolidation deficits in the CREB-deficient mice. Finally we show that disrupting either NMDA or calcium/calmodulin-dependent kinase II (CaMKII) function impairs consolidation of context memories. Together, these data suggest that this approach is particularly suited for the characterization of molecular and cellular processes underlying the formation of stimulus representations. © 2004 Wiley-Liss, Inc. [source]


The surface radiation budget over North America: gridded data assessment and evaluation of regional climate models

INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 15 2009
Marko Markovic
Abstract While surface station observations of downwelling radiation offer accuracy at high temporal resolution, they do not easily allow an evaluation of model surface radiation budgets (SRB) over a wide geographical area. We evaluate three gridded SRB data sets against detailed observations from six surface radiation sites from the US surface radiation (SURFRAD) network. We subsequently use the most accurate surrogate observational data set for evaluation of model-simulated SRB. The data sets assessed are: ERA40,reanalysis of European Centre for Medium-Range Weather Forecasts (ECMWF), North American Regional Reanalysis (NARR),regional reanalysis of National Centres for Environmental Prediction (NCEP) and the surface radiative budget (SRB) from the International Satellite Cloud Climatology Project (ISCCP). Due to varying constraints with respect to temporal coverage of each data set, the evaluation period used in this study is 1996,2001, inclusive. The ERA40 downwelling longwave radiation (DLR) appears the most accurate surrogate observation, while both ERA40 and ISCCP show accurate results when the incoming shortwave radiation (ISR) is considered across the annual cycle. Winter DLR is less accurate in ISCCP with a positive bias and lack of very low (<200 Wm,2) flux values. The NARR SRB shows a large positive bias in the ISR throughout the annual cycle, linked to a significant underestimate of cloud cover. The ERA40 data are subsequently used to evaluate the simulated SRB in three regional climate models across North America. With respect to solar radiation, cloud cover biases are seen to be crucial, while for longwave fluxes both cloud fraction and in-cloud water content are important to simulate correctly. Inclusion of trace gases beyond H2O, CO2 and O3 appears necessary for an accurate calculation of clear-sky longwave radiation. Error compensation frequently occurs between the various components contributing to a model total-sky SRB. This is important to consider when trying to identify the underlying causes of errors in the simulated total SRB. Copyright © 2009 Royal Meteorological Society [source]


DFT study of polymorphism of the DNA double helix at the level of dinucleoside monophosphates

INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 13 2010
Valeri I. Poltev
Abstract We apply DFT calculations to deoxydinucleoside monophosphates (dDMPs) which represent minimal fragments of the DNA chain to study the molecular basis of stability of the DNA duplex, the origin of its polymorphism and conformational heterogeneity. In this work, we continue our previous studies of dDMPs where we detected internal energy minima corresponding to the "classical" B conformation (BI-form), which is the dominant form in the crystals of oligonucleotide duplexes. We obtained BI local energy minima for all existing base sequences of dDMPs. In the present study, we extend our analysis to other families of DNA conformations, successfully identifying A, BI, and BII energy minima for all dDMP sequences. These conformations demonstrate distinct differences in sugar ring puckering, but similar sequence-dependent base arrangements. Internal energies of BI and BII conformers are close to each other for nearly all the base sequences. The dGpdG, dTpdG, and dCpdA dDMPs slightly favor the BII conformation, which agrees with these sequences being more frequently experimentally encountered in the BII form. We have found BII-like structures of dDMPs for the base sequences both existing in crystals in BII conformation and those not yet encountered in crystals till now. On the other hand, we failed to obtain dDMP energy minima corresponding to the Z family of DNA conformations, thus giving us the ground to conclude that these conformations are stabilized in both crystals and solutions by external factors, presumably by interactions with various components of the media. Overall the accumulated computational data demonstrate that the A, BI, and BII families of DNA conformations originate from the corresponding local energy minimum conformations of dDMPs, thus determining structural stability of a single DNA strand during the processes of unwinding and rewinding of DNA. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem 110:2548,2559, 2010 [source]


The Usefulness of Measures of Consistency of Discretionary Components of Accruals in the Detection of Earnings Management

JOURNAL OF BUSINESS FINANCE & ACCOUNTING, Issue 9-10 2009
Salma S. IbrahimArticle first published online: 26 OCT 200
Abstract:, Prior research has shown the prevalence of measurement error in models used to estimate aggregate discretionary accruals. In these models, the incremental information content of the various components of accruals is ignored. Limited prior research and data gathered from firms under Securities and Exchange Commission (SEC) litigation indicate that managers use either one or more than one component of accruals simultaneously, in a consistent way to manipulate bottom-line earnings in a given direction. I propose two measures that capture the consistency between the discretionary components of accruals and test their significance in earnings management (EM) detection in firms that have artificially added accrual manipulation and firms that were targeted by the SEC for accrual manipulation. There is evidence that this information is incrementally useful in detecting EM. This finding paves the way for improvements in the discretionary accruals measure by including consistency information from the components of aggregate accruals. [source]


Metabolic syndrome, insulin resistance, and periodontitis: a cross-sectional study in a middle-aged French population

JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 7 2010
Catherine Benguigui
Benguigui C, Bongard V, Ruidavets J-B, Chamontin B, Sixou M, Ferrières J, Amar J. Metabolic syndrome, insulin resistance and periodontitis: a cross-sectional study in a middle-aged French population. J Clin Periodontol 2010; 37: 601,608. doi: 10.1111/j.1600-051X.2010.01571.x. Abstract Aim: Metabolic syndrome consists of a cluster of clinical and biological abnormalities, influenced by insulin resistance and promoting cardiovascular diseases. We examined the relationships between metabolic syndrome, its various components, insulin resistance, and periodontitis. Materials and Methods: The study included 276 subjects (35,74 years) recruited within a cross-sectional survey on cardiovascular risk factors. Twenty-one were excluded because of infectious risk or total tooth loss. Clinical attachment loss (CAL), probing pocket depth (PD), gingival and plaque indexes were recorded. Periodontitis was classified into moderate and severe forms. Results: The mean age was 58, 41% of the subjects had moderate and 39% had severe periodontitis. In univariate comparisons, periodontitis was associated with metabolic syndrome (p=0.050), most of its components, and HOMA index (homoeostasis model assessment of insulin resistance). After adjustment for confounders, only HOMA index remained associated with severe periodontitis (odds ratio [OR]=3.97 [95% confidence interval: 1.22,12.9], OR=3.78 [1.14,12.5] for third and fourth versus the first quartile of the HOMA index, respectively). The HOMA index was also associated with the number of periodontal sites with CAL4 mm, CAL5 mm, or PD4 mm (greater number for higher HOMA-index values). This relationship disappeared in never-smokers. Conclusions: Our data support the relationships between metabolic disturbances and periodontitis, with a central role of insulin resistance. [source]


Advanced relationships between categories analysis as a qualitative research tool

JOURNAL OF CLINICAL PSYCHOLOGY, Issue 7 2010
Merav Rabinovich
Abstract The authors propose an advanced relationships between categories (RBC) model as an expansion of Tutty, Rothery, and Grinnell's (1996) qualitative tool for classifying RBC patterns as contained, temporal, and causal relationships. It is assumed that identification of the relationships obtained among categories of qualitative data paves the way for construction of a theory, even though few tools have been developed for this purpose to date. The advanced RBC model points to three additional relationship patterns: bilateral, trilateral, and quadrilateral relationships. These relationships reveal how the text itself links among its various components. The model serves as an innovative tool for systematic derivation of explanations based on the qualitative raw data, contributing to grounded theory and other interpretive studies. © 2010 Wiley Periodicals, Inc. J Clin Psychol: 66:1,11, 2010. [source]


Predicting the tautomeric equilibrium of acetylacetone in solution.

JOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 4 2010

Abstract This study investigates how the various components (method, basis set, and treatment of solvent effects) of a theoretical approach influence the relative energies between keto and enol forms of acetylacetone, which is an important model system to study the solvent effects on chemical equilibria from experiment and theory. The computations show that the most popular density functional theory (DFT) approaches, such as B3LYP overestimate the stability of the enol form with respect to the keto form by ,10 kJ mol,1, whereas the very promising SCS-MP2 approach is underestimating it. MP2 calculations indicate that in particular the basis set size is crucial. The Dunning Huzinaga double , basis (D95z(d,p)) used in previous studies overestimates the stability of the keto form considerably as does the popular split-valence plus polarization (SVP) basis. Bulk properties of the solvent included by continuum approaches strongly stabilize the keto form, but they are not sufficient to reproduce the reversal in stabilities measured by low-temperature nuclear magnetic resonance experiments in freonic solvents. Enthalpic and entropic effects further stabilize the keto form, however, the reversal is only obtained if also molecular effects are taken into account. Such molecular effects seem to influence only the energy difference between the keto and the enol forms. Trends arising due to variation in the dielectric constant of the solvent result from bulk properties of the solvent, i.e., are already nicely described by continuum approaches. As such this study delivers a deep insight into the abilities of various approaches to describe solvent effects on chemical equilibria. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010 [source]


Occupational embeddedness and job performance

JOURNAL OF ORGANIZATIONAL BEHAVIOR, Issue 7 2009
Thomas W. H. Ng
While researchers have recently focused their attention on organizational embeddedness, occupational embeddedness has received little theoretical and empirical attention. Using multisource data on 162 employees in multiple jobs and organizations, we found that occupational embeddedness is positively related to both task performance and creativity and is negatively related to counterproductive work behavior, even after controlling for the effects of organizational embeddedness. In addition, we found that trait affect moderated the relationships of occupational embeddedness to job performance. Occupational embeddedness was more strongly related to counterproductive work behavior when trait negative affect was high, while occupational embeddedness was more strongly related to both citizenship behavior and creativity when trait positive affect was high. Results also indicated that the various components of occupational embeddedness had different effects on job outcomes. Fit had a strong positive effect on core task performance, links had a positive effect on creativity, and sacrifice had a small positive effect on citizenship behavior. The article concludes with a discussion of implications for future research and management practice. Copyright © 2009 John Wiley & Sons, Ltd. [source]


In-vitro Antioxidant and In-vivo Photoprotective Effect of Three Lyophilized Extracts of Sedum telephium L. Leaves

JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 10 2000
FRANCESCO BONINA
Sedum telephium L. is a medicinal plant used in antiquity to cure many types of inflammatory skin diseases. The leaves (without the external cuticle), are used to promote healing and reduce skin inflammation and pain, and contain various components. We found two major components: flavonol glycosides and polysaccharides, with molecular weight between 13 000 and 13 500 Da. We evaluated the in-vitro antioxidant and in-vivo skin photoprotective effects of three lyophilized extracts obtained from the juice of S. telephium L. leaves: a total lyophilized juice, a lyophilized flavonolic fraction, and a lyophilized polysaccharidic fraction. Two in-vitro models were used: the bleaching of the stable 2,2-diphenyl-1-picrylhydrazyl (DPPH*) radical, and the protective effect against UV-induced peroxidation on phosphatidylcholine multilamellar vesicles, as model membranes. The antioxidant/radical scavenging activity of each lyophilized extract was also assessed in-vivo by determining their ability to reduce UVB-induced skin erythema (monitored by reflectance spectrophotometry) in healthy human volunteers. The findings of the in-vitro experiments clearly demonstrated that, unlike the lyophilized polysaccharidic fraction, the lyophilized flavonolic fraction and total lyophilized juice possess strong antioxidant/free radical scavenging properties, which are likely due to phenolic compounds. Consistent with these findings, gel formulations of both the total lyophilized juice and, to a greater degree, the lyophilized flavonolic fraction appeared to possess a strong protective effect against UV-induced skin erythema in-vivo, whereas the lyophilized polysaccharidic fraction was completely ineffective. The in-vitro and in-vivo results suggest that, both the total lyophilized juice and, in particular, the lyophilized flavonolic fraction, but not the lyophilized polysaccharidic fraction of S. telephium L. leaves, have photoprotective effects against UVB-induced skin damage. [source]


Macromolecular design via reversible addition,fragmentation chain transfer (RAFT)/xanthates (MADIX) polymerization

JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 22 2005
Sébastien Perrier
Abstract Among the living radical polymerization techniques, reversible addition,fragmentation chain transfer (RAFT) and macromolecular design via the interchange of xanthates (MADIX) polymerizations appear to be the most versatile processes in terms of the reaction conditions, the variety of monomers for which polymerization can be controlled, tolerance to functionalities, and the range of polymeric architectures that can be produced. This review highlights the progress made in RAFT/MADIX polymerization since the first report in 1998. It addresses, in turn, the mechanism and kinetics of the process, examines the various components of the system, including the synthesis paths of the thiocarbonyl-thio compounds used as chain-transfer agents, and the conditions of polymerization, and gives an account of the wide range of monomers that have been successfully polymerized to date, as well as the various polymeric architectures that have been produced. In the last section, this review describes the future challenges that the process will face and shows its opening to a wider scientific community as a synthetic tool for the production of functional macromolecules and materials. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43:5347,5393, 2005 [source]


Alcohol Primes the Airway for Increased Interleukin-13 Signaling

ALCOHOLISM, Issue 3 2009
Patrick O. Mitchell
Background:, Using an experimental model of airway fibrosis following lung transplantation, we recently showed that chronic alcohol ingestion by donor rats amplifies airway fibrosis in the recipient. Associated with alcohol-mediated amplification of airway fibrosis is increased transforming growth factor ,-1(TGF,1) and ,-smooth muscle actin expression. Other studies have shown that interleukin-13 (IL-13) modulates TGF,1 signaling during experimentally-induced airway fibrosis. Therefore, we hypothesized that IL-13 is a component of alcohol-mediated amplification of pro-fibrotic mediators in the alcoholic lung. Methods:, To test this hypothesis, we analyzed tracheal epithelial cells and type II alveolar cells from control- or alcohol-fed rats, alcohol-treated mouse lung fibroblasts, and human bronchial epithelial cells in vitro for expression of various components of the IL-13 signaling pathway. Signaling via the IL-13 pathway was assessed by measuring levels of phosphorylated signal transducers and activators of transcription-6 (STAT6). In addition, we performed heterotopic tracheal transplantation using control-fed and alcohol-fed donor rats and analyzed tracheal allografts for expression of components of the IL-13 signaling pathway by RT-PCR and immunocytochemical analyses. Results:, Interleukin-13 expression was detected in type II alveolar epithelial cells and human bronchial epithelial cells, but not in lung fibroblasts. IL-13 expression was decreased in whole lung and type II cells in response to alcohol exposure. In all cell types analyzed, expression of IL-13 signaling receptor (IL-13R,1) mRNA was markedly increased. In contrast, mRNA and protein expression of the IL-13 decoy receptor (IL-13R,2) were decreased in all cells analyzed. Exposure to alcohol also increased STAT6 phosphorylation in response to IL-13 and lipopolysaccharide. Conclusions:, Data from multiple cell types in the pulmonary system suggest that IL-13 and its receptors play a role in alcohol-mediated activation of pro-fibrotic pathways. Taken together, these data suggest that alcohol primes the airway for increased IL-13 signaling and subsequent tissue remodeling upon injury such as transplantation. [source]


A friction energy approach to quantifying lubrication under fretting sliding

LUBRICATION SCIENCE, Issue 2 2010
T. Kolodziejczyk
Abstract The problem of a proper lubrication under low-speed small oscillatory movement can be a decisive factor for the reliability of various components. There is a need to characterise the lubricious behaviour of the interface under oil-bath fretting wear conditions for ball bearing applications. Fast and reliable methods to quantify this behaviour for broad range of mechanical conditions are proposed and validated. Pure sliding reciprocation induces mixed lubrication mode. It was found that transient film profiles depend on the non-Newtonian response of the oils and the type of motion. Running-in period has a crucial importance for the tribofilm formation, and is a result of the interplay of the oil-sliding surfaces interface and is directly connected with the total energy dissipated from the contact region. The stability of structured tribofilm in steady-state period relies on the balance between the competitive processes: replenishment of the oil to the contact and ejection of the oil pending the oscillatory movement. The phenomenon of starvation was observed when the system was moved away from dynamical equilibrium and the growth of the dissipated energy was spotted. A proposed methodology provides the evaluation of the lubrication properties of the oil in a quantitative way. Copyright © 2010 John Wiley & Sons, Ltd. [source]


Nutrition in the genomics era: Cardiovascular disease risk and the Mediterranean diet

MOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 10 2007
Jose M. Ordovas
Abstract The effect of dietary changes on phenotypes (i.e., plasma lipid measures, body weight and blood pressure) differs significantly between individuals. This phenomenon has been more extensively researched in relation to changes in dietary fat and plasma lipid concentrations for the prevention of cardiovascular disease (CVD) compared to other pathological conditions. Although common knowledge associates low fat diets with reductions in total and plasma LDL cholesterol, the clinical evidence shows dramatic inter-individual differences in response that are partially due to genetic factors. The discovery of the cardioprotective and other healthy properties of the Mediterranean diet has popularized the consumption of Mediterranean products such as olive oil. Molecular, clinical, and epidemiological studies have begun to shed some light about how various components of this diet may protect the cardiovascular system and to decrease the risk of other diseases such as cancer. However, it is also possible that the right combination of genetic, cultural, socioeconomic factors is needed to achieve full benefit. It has been proposed that the Mediterranean diet may be closer to the ancestral foods that were part of human development and our metabolism may have evolved to work optimally on such a diet rather than with the current diets richer in saturated fat and highly refined and processed foods. Therefore, it is possible that alleles that are associated with increase disease risk may be silenced in the presence of that more ancestral and traditional diet and lifestyle. This knowledge may provide the basis for successful public health as well individual approaches for disease prevention. [source]


Achieving a Safety Culture in Obstetrics

MOUNT SINAI JOURNAL OF MEDICINE: A JOURNAL OF PERSONALIZED AND TRANSLATIONAL MEDICINE, Issue 6 2009
Erin DuPree MD
Abstract Preventable maternal and neonatal mortalities still occur, despite the wonders of today's technologically advanced healthcare system. Delivering high-quality, consistent care is the goal of every provider. Yet, obstetrical practice, in which unpredictable events and high-risk situations are the norm, is particularly vulnerable to medical errors. Obstetrics departments should be striving for a climate of patient safety, one that includes a just, reporting, and learning culture. This article discusses the various components of a safety culture as well as some of the advances that are being made in the field to improve the quality of care in obstetrics. Mt Sinai J Med 76:529-538, 2009. © 2009 Mount Sinai School of Medicine [source]


Experiences of intensive care nurses assessing sedation/agitation in critically ill patients

NURSING IN CRITICAL CARE, Issue 4 2008
Stephanie Weir
Abstract Background:, Patients admitted to the intensive care unit (ICU) will more often than not require sedative and analgesic drugs to enable them to tolerate the invasive procedures and therapies caused as a result of their underlying condition and/or necessary medical interventions. Aim:, This article reports a study exploring the perceptions and experiences of intensive care nurses using a sedation/agitation scoring (SAS) tool to assess and manage sedation and agitation amongst critically ill patients. The principle aims and objectives of this study were as follows: ,,to explore nurse's everyday experiences using a sedation scoring tool; ,,to explore and understand nurse's attitudes and beliefs of the various components of assessing and managing sedation among critically ill patients. Method:, Using a descriptive qualitative approach, semistructured interviews were carried out with a purposive sample of eight ICU nurses within a district general hospital ICU. The interviews focused on nurse's own experiences and perceptions of using a sedation scoring tool in clinical practice. Burnard's 14-stage thematic content analysis framework was employed to assist in the data analysis process. Results:, Three key themes emerged that may have implications not only for clinical practice but for further research into the use of the SAS tool. ,,Benefits to patient care as a direct result of using a sedation scoring tool. ,,The concerns of nursing staff. ,,The implications of using such a tool in clinical practice. Conclusion:, This paper reinforces the potential benefits to patients as a direct result of implementing the SAS scoring tool and clinical guidelines. Furthermore, it highlights the reluctance of a number of staff to adhere to such guidelines and discusses the concerns regarding less experienced nurses administering sedative agents. Attention was also drawn to the educational requirements of nursing and medical staff when using the SAS scoring tool. [source]