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Selected AbstractsEffects of 4-nonylphenol on the endocrine system of the shore crab, Carcinus maenasENVIRONMENTAL TOXICOLOGY, Issue 3 2008Christina M. Lye Abstract There is a considerable body of evidence to suggest that many anthropogenic chemicals, most notably xeno-estrogens, are able to disrupt the endocrine system of vertebrates. There have been few comparable studies on the effects of exposure to these chemicals that may serve as biomarkers of endocrine disruption in aquatic invertebrate species. In addition, the evidence available is complex, conflicting, and far from conclusive. The present study aimed to investigate the impact of the xeno-estrogen 4-nonylphenol (4-NP, nominal concentrations 10,100 ,g L,1) on the regulation and functioning of the endocrine system of the shore crab Carcinus maenas. It also set out to establish whether 4-NP are causing the effects (i.e., changes of exoskeletons including secondary sexual characteristics, pheromonally mediated behavior and ecdysone levels, and the presence of vt in the male hepatopancreas) found recently in wild shore crabs (Lye et al.,2005). The study utilizes morphological (e.g., gonadosomatic and hepatosomatic indices) and hormonal (ecdysteroid moulting hormone levels and the induction of female specific proteins, vitellins) biomarkers using radioimmunoassay and an indirect enzyme linked immunosorbent assay applied to the soluble protein fraction of adult male hepatopancreatic homogenates. Exposure of C. maenas to an effective concentration as low as 1.5 ,g L,1 4-NP resulted in a reduced testis weight, increased liver weight, and altered levels of ecdysone equivalents compared to controls. Induction of vitellin-like proteins was absent in all samples tested. The ecological implications and the possible mechanisms for the action of 4-NP on the response of the shore crab to xeno-estrogen exposure are discussed. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2008. [source] Evidence for canalization of Distal-less function in the leg of Drosophila melanogasterEVOLUTION AND DEVELOPMENT, Issue 2 2005Ian Dworkin Summary A considerable body of theory pertaining to the evolution of canalization has emerged recently, yet there have been few empirical investigations of their predictions. To address this, patterns of canalization and trait correlation were investigated under the individual and joint effects of the introgression of a loss-of-function allele of the Distal-less gene and high-temperature stress on a panel of iso-female lines. Variation was examined for number of sex comb teeth and the length of the basi-tarsus on the pro-thoracic leg of male Drosophila melanogaster. I demonstrate that whereas there is evidence for trait canalization, there is no evidence to support the hypothesis of the evolution of genetic canalization as a response to microenvironmental canalization. Furthermore, I demonstrate that although there are genetic correlations between these traits, there is no association between their measures of canalization. I discuss the prospects of the evolutionary lability of the Distal-less gene within the context of changes in genetic variation and covariation. [source] Neutron Activation Analysis, Atomic Absorption and X-Ray Fluorescence Spectrometry Review for 2003GEOSTANDARDS & GEOANALYTICAL RESEARCH, Issue 1 2005L. Paul Bédard This review for the year 2003 deals with three relatively well-established, mature, analytical techniques (neutron activation analysis, atomic absorption spectrometry and X-ray fluorescence spectrometry) that nevertheless remain very important for the characterisation of geological and environmental samples. Developments in neutron activation analysis included modification to the technique in relation to the determination of platinum-group elements, as well as consideration of sample size in ore grade estimation. A considerable body of literature was published on the application of atomic absorption spectrometry in the analysis of environmental samples. Many of these proposed technical and methodological improvements, notably in extraction procedures. X-ray fluorescence spectrometry saw developments in in situ analysis, synchrotron micro-XRF (,-SRXRF) and a confocal X-ray set-up for 3D elemental imaging. XRF technologies were used in the analysis of geological samples, reference materials, glasses, solutes and environmental materials. [source] Towards a distinctive body of knowledge for Information Systems experts: coding ISD process knowledge in two IS journalsINFORMATION SYSTEMS JOURNAL, Issue 4 2004Juhani Iivari Abstract., This paper introduces the idea of coding a practically relevant body of knowledge (BoK) in Information Systems (IS) that could have major benefits for the field. In its main part, the paper focuses on the question if and how an underlying body of action-oriented knowledge for IS experts could be distilled from the IS research literature. For this purpose the paper identifies five knowledge areas as the most important parts for an IS expert's BoK. Two of these are claimed as distinct areas of competence for IS experts: IS application knowledge and IS development (ISD) process knowledge. The paper focuses particularly on ISD process knowledge because it allows the organizing of practically relevant IS knowledge in an action-oriented way. The paper presents some evidence for the claim that a considerable body of practically relevant IS process knowledge might, indeed, exist, but also notes that it is highly dispersed in the IS literature. It then argues that the IS research community should take stock of this knowledge and organize it in an action-oriented way. Based on results from prior work it proposes a four-level hierarchical coding scheme for this purpose. In order to test the idea of coding action-oriented knowledge for IS experts, the paper reports the results of a coded literature analysis of ISD research articles published from 1996 to 2000 in two leading IS journals , Information Systems Journal and MIS Quarterly. The results suggest that ISD approaches form a useful framework for organizing practically relevant IS knowledge. [source] The meaning of good and bad care in the community care: older people's lived experiencesINTERNATIONAL JOURNAL OF OLDER PEOPLE NURSING, Issue 3 2009Ingrid From MSc In spite of a considerable body of research in the past decades on what does or does not constitute good care for older people, there are still few studies addressing this question in which older people narrate their experiences of being dependent on community care. This study was therefore carried out aiming to explore older people's lived experiences of what good and bad care meant to them, when it was offered by community care services. Nineteen older persons in three Swedish communities participated in the study, which used a phenomenological,hermeneutic approach. Data were collected through unstructured interviews and Colaizzi's framework was utilized in the analysis of the data. The key theme arising from the analysis was that of being encountered as a human being by caregivers who, through the provision of safe and secure care, provide opportunities for living life as usual. When any of these circumstances are lacking, bad care will be the consequence. As the general intention in society is to ensure good quality of care to older people as well as others, the findings in our study should have important implications for providers of community care for older people. [source] How practitioners can systematically use empirical evidence in treatment selectionJOURNAL OF CLINICAL PSYCHOLOGY, Issue 10 2002Larry E. Beutler Contemporary concerns with "empirically supported treatments" emphasize the differences in outcomes that are associated with reliably delivered treatments, representing different models and theories. This approach often fails to address the fact that there is no consensus among scientists about whether there are enough differences between and among treatments to make this effort productive. There is a considerable body of data that suggests that all treatments produce very similar effects. This article reviews these viewpoints and presents a third position, suggesting that identifying common and differential principles of change may be more productive than focusing on the relative value of different theoretical models. © 2002 Wiley Periodicals, Inc. J Clin Psychol 58: 1199,1212, 2002. [source] Contemporary Australian outcomes in childhood and adolescent type 1 diabetes: 10 years post the Diabetes Control and Complications TrialJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 7-8 2006Geoffrey R Ambler Abstract: The reporting of the results of the Diabetes Control and Complications Trial in 1993 has led to a major reappraisal of management practices and outcomes in type 1 diabetes in children and adolescents. A considerable body of outcome data has been generated from Australia in this post-Diabetes Control and Complications Trial era relating to incidence, metabolic control, growth, hypoglycaemia, microvascular and macrovascular complications, cognition, behaviour and quality of life. These data are important in planning future management strategies and resource allocation and as a basis for future research. [source] Alcohol in Moderation, Cardioprotection, and Neuroprotection: Epidemiological Considerations and Mechanistic StudiesALCOHOLISM, Issue 2 2009Michael A. Collins In contrast to many years of important research and clinical attention to the pathological effects of alcohol (ethanol) abuse, the past several decades have seen the publication of a number of peer-reviewed studies indicating the beneficial effects of light-moderate, nonbinge consumption of varied alcoholic beverages, as well as experimental demonstrations that moderate alcohol exposure can initiate typically cytoprotective mechanisms. A considerable body of epidemiology associates moderate alcohol consumption with significantly reduced risks of coronary heart disease and, albeit currently a less robust relationship, cerebrovascular (ischemic) stroke. Experimental studies with experimental rodent models and cultures (cardiac myocytes, endothelial cells) indicate that moderate alcohol exposure can promote anti-inflammatory processes involving adenosine receptors, protein kinase C (PKC), nitric oxide synthase, heat shock proteins, and others which could underlie cardioprotection. Also, brain functional comparisons between older moderate alcohol consumers and nondrinkers have received more recent epidemiological study. In over half of nearly 45 reports since the early 1990s, significantly reduced risks of cognitive loss or dementia in moderate, nonbinge consumers of alcohol (wine, beer, liquor) have been observed, whereas increased risk has been seen only in a few studies. Physiological explanations for the apparent CNS benefits of moderate consumption have invoked alcohol's cardiovascular and/or hematological effects, but there is also experimental evidence that moderate alcohol levels can exert direct "neuroprotective" actions,pertinent are several studies in vivo and rat brain organotypic cultures, in which antecedent or preconditioning exposure to moderate alcohol neuroprotects against ischemia, endotoxin, ,-amyloid, a toxic protein intimately associated with Alzheimer's, or gp120, the neuroinflammatory HIV-1 envelope protein. The alcohol-dependent neuroprotected state appears linked to activation of signal transduction processes potentially involving reactive oxygen species, several key protein kinases, and increased heat shock proteins. Thus to a certain extent, moderate alcohol exposure appears to trigger analogous mild stress-associated, anti-inflammatory mechanisms in the heart, vasculature, and brain that tend to promote cellular survival pathways. [source] Unproven diagnostic procedures in IgE-mediated allergic diseasesALLERGY, Issue 8 2004B. Niggemann A considerable body of literature on therapeutic aspects of complementary and alternative medicine has been published in recent years, but little is known on diagnostic procedures. This short review lists complementary and alternative diagnostic procedures for the diagnosis of allergic diseases and presents an assessment of their usefulness for the daily practice. The review of the literature revealed that neither the determination of specific immunoglobulin G-antibodies in serum, the hair-analysis, the cytotoxic test, kinesiology, iridology, or electrodermal testing represent useful tests for the daily practice. To date, no complementary or alternative diagnostic procedure can be recommended as a meaningful element in the diagnostic work-up of allergic diseases. This is especially true for food allergy: properly performed oral food challenges still represent the gold standard for implementing specific diets in food allergic individuals. Ineffective diagnostic approaches may be costly for the consumer and delay appropriate therapy. [source] Evidence for shutter-speed variation in CR bolus-tracking studies of human pathologyNMR IN BIOMEDICINE, Issue 3 2005Thomas E. Yankeelov Abstract The standard pharmacokinetic model for the analysis of MRI contrast reagent (CR) bolus-tracking (B-T) data assumes that the mean intracellular water molecule lifetime (,i) is effectively zero. This assertion is inconsistent with a considerable body of physiological measurements. Furthermore, theory and simulation show the B-T time-course shape to be very sensitive to the ,i magnitude in the physiological range (hundreds of milliseconds to several seconds). Consequently, this standard model aspect can cause significant underestimations (factors of 2 or 3) of the two parameters usually determined: Ktrans, the vascular wall CR transfer rate constant, and ve, the CR distribution volume (the extracellular, extravascular space fraction). Analyses of animal model data confirmed two predicted behaviors indicative of this standard model inadequacy: (1) a specific temporal pattern for the mismatch between the best-fitted curve and data; and (2) an inverse dependence of the curve's Ktrans and ve magnitudes on the CR dose. These parameters should be CR dose-independent. The most parsimonious analysis allowing for realistic ,i values is the ,shutter-speed' model. Its application to the experimental animal data essentially eliminated the two standard model signature inadequacies. This paper reports the first survey for the extent of this ,shutter-speed effect' in human data. Retrospective analyses are made of clinical data chosen from a range of pathology (the active multiple sclerosis lesion, the invasive ductal carcinoma breast tumor, and osteosarcoma in the leg) that provides a wide variation, particularly of Ktrans. The signature temporal mismatch of the standard model is observed in all cases, and is essentially eliminated by use of the shutter-speed model. Pixel-by-pixel maps show that parameter values from the shutter-speed analysis are increased by more than a factor of 3 for some lesion regions. This endows the lesions with very high contrast, and reveals heterogeneities that are often not seen in the standard model maps. Normal muscle regions in the leg allow validation of the shutter-speed model Ktrans, ve, and ,i magnitudes, by comparison with results of previous careful rat leg studies not possible for human subjects. Copyright © 2004 John Wiley & Sons, Ltd. [source] The Global System of FinanceAMERICAN JOURNAL OF ECONOMICS AND SOCIOLOGY, Issue 1 2006Niklas Luhmann for Theoretical Keystones, Scanning Talcott Parsons In the last decades, revolutionary changes in financial markets, instruments, and institutions have stimulated empirical and theoretical investigations into the interaction of the financial and the "real" side of economic systems. While a considerable body of empirical investigations seems to provide evidence of positive correlations between stock market development and economic growth, there is no consensus in other social sciences as to whether there are two-way linkages, and if so, how to conceive a possible mechanism of interaction. Particularly, the hypergrowth and ubiquity of financial markets has triggered controversial debates on how to understand today's economic landscape. With the objective of clarifying the relationship between finance and economy, this article restructures the present debate through the lenses of Talcott Parsons's and Niklas Luhmann's theories of social systems. Basic system-theoretical ideas on social aspects of finance and economy as well as on uncertainty and risk hint at new insights into the global system of finance that might go far beyond explanatory models of causality. [source] Housing Markets And Regional Unemployment Flows In Great BritainTHE MANCHESTER SCHOOL, Issue 2 2003Martin T. Robson Over the past 20 years, there has been a great deal of interest from academic economists and policymakers in the UK in the contribution of the housing market to regional disparities in unemployment. However, despite a considerable body of research, there remains a great deal of uncertainty concerning the role played by different features of the housing market in shaping the regional pattern of unemployment. In this study, we aim to gain a deeper understanding of this issue by examining the relationship between housing market variables and the flows into and out of regional unemployment. Our findings indicate that both the level of regional house prices and the housing tenure mix have significant effects on the rate of flows into and out of regional unemployment and hence upon the equilibrium rate of unemployment in a region. In particular, we find that regions with a relatively high level of house prices and/or a low proportion of social rented housing will tend to have a relatively low equilibrium rate of unemployment, other things equal. [source] Nonsense-mediated decay: paving the road for genome diversificationBIOESSAYS, Issue 10 2008Francisco Sánchez-Sánchez The expression of protein-encoding genes is a complex process culminating in the production of mature mRNA and its translation by the ribosomes. The production of a mature mRNA involves an intricate series of processing steps. The majority of eukaryotic protein-encoding genes contain intron sequences that disrupt the protein-encoding frame, and hence have to be removed from immature mRNA prior to translation into protein. The mechanism involved in the selection of correct splice sites is incompletely understood. A considerable body of evidence suggests that the splicing machinery has suboptimal efficiency and fidelity leading to substantial processing inaccuracy. Here we discuss a recently published article1 that extends observations that cells rely on nonsense- mediated mRNA decay (NMD) to compensate for such suboptimal processing accuracy. Intriguingly these authors provide evidence for a strong selective pressure in favour of premature termination of mRNA translation in the event of intron retention. The analysis presented implies a positive role of NMD in transcript diversification through alternative splicing and suggest that this ancient surveillance mechanism may have co-evolved with intron acquisition born from the need for quality control of splicing patterns. BioEssays 30:926,928, 2008. © 2008 Wiley Periodicals, Inc. [source] Protease-activated receptors and prostaglandins in inflammatory lung diseaseBRITISH JOURNAL OF PHARMACOLOGY, Issue 4 2009Terence Peters Protease-activated receptors (PARs) are a novel family of G protein-coupled receptors. Signalling through PARs typically involves the cleavage of an extracellular region of the receptor by endogenous or exogenous proteases, which reveals a tethered ligand sequence capable of auto-activating the receptor. A considerable body of evidence has emerged over the past 20 years supporting a prominent role for PARs in a variety of human physiological and pathophysiological processes, and thus substantial attention has been directed towards developing drug-like molecules that activate or block PARs via non-proteolytic pathways. PARs are widely expressed within the respiratory tract, and their activation appears to exert significant modulatory influences on the level of bronchomotor tone, as well as on the inflammatory processes associated with a range of respiratory tract disorders. Nevertheless, there is debate as to whether the principal response to PAR activation is an augmentation or attenuation of airways inflammation. In this context, an important action of PAR activators may be to promote the generation and release of prostanoids, such as prostglandin E2, which have well-established anti-inflammatory effects in the lung. In this review, we primarily focus on the relationship between PARs, prostaglandins and inflammatory processes in the lung, and highlight their potential role in selected respiratory tract disorders, including pulmonary fibrosis, asthma and chronic obstructive pulmonary disease. This article is part of a themed issue on Mediators and Receptors in the Resolution of Inflammation. To view this issue visit http://www3.interscience.wiley.com/journal/121548564/issueyear?year=2009 [source] Face down posturing for macular hole surgery.ACTA OPHTHALMOLOGICA, Issue 2009Is it really required? Purpose Background: In macular hole surgery pars plana vitrectomy and intravitreal gas injection with or without inner limiting membrane peel, is considered the mainstay of treatment. The requirement for face down posturing is generally regarded as part of the traditional postoperative routine. Several mechanisms have been postulated to explain the action of the gas bubble including exertion of a large floatation force on the macula and prevention of the macular hole exposure to vitreous fluid. Recently the need to face down has been chalenged since this regime compromises patients' postoperative quality of life and it makes macular hole surgery almost impossible for individuals with mental or physical limitations. Methods Review of personal data and systermatic literature review of studies investigating macular hole surgery with shortened or eliminated face down posturing. Results There is considerable body of evidence suggesting successful anatomical and functional outcome in patients with shorter duration of posturing or no posturing at all following macular hole surgery. The pros and cons of each technique will be presented in detail. Conclusion Prone posturing following macular hole surgery provides no functional or anatomic benefit but it is associated with slower progression of cataract. Combined phacovitrectomy without face down positioning may be considered for phakic patients undergoing macular hole surgery. [source] Emotional processing in children with conduct problems and callous/unemotional traitsCHILD: CARE, HEALTH AND DEVELOPMENT, Issue 2 2008M. Woodworth Abstract Background A considerable body of evidence now suggests that conduct problem (CP) children with callous/unemotional (CU) traits differ in many ways from CP children without these characteristics. Previous research has suggested that there are important differences for youth with CP and CU characteristics in their ability to process emotional information. The current study investigated the ability of children with disruptive behaviour disorders to label emotional faces and stories. Methods Participants (aged 7,12) were involved in a summer day treatment and research programme for children with disruptive behaviour problems. Two tasks were administered that were designed to measure participant's ability to recognize and label facial expressions of emotion, as well as their ability to label emotions in hypothetical situations. Results Results indicated that children with higher levels of CU traits, regardless of whether they had elevated CP scores, were less accurate in identifying sad facial expressions. Interestingly, children with higher CU scores were more accurate in labelling fear than were children with lower CU scores, while children with high CP but low CU traits were less accurate than other children in interpreting fearful facial emotions. Further, children's recognition of various emotional vignettes was not associated with CP, CU traits or their interaction. Conclusions The current study demonstrated that it was the combination of CP and a high number of CU traits that differentiated emotional attributions. Consistent with previous research, youth with CU traits had more difficulty in identifying sad facial expressions. However, contrasting with some previous studies, higher CU traits were associated with more accurate perceptions of fearful expressions. It is possible that there is something specific to fear recognition for individuals with more psychopathic, CU traits that actually make them more successful for observing or recognizing fearful expressions. Additional research is needed to clarify both the recognition and processing of fear expression in CP children with and without CU. [source] | |||||||||||||||||||