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Qualitative Changes (qualitative + change)
Selected AbstractsIn Defense of Qualitative Changes in DevelopmentCHILD DEVELOPMENT, Issue 6 2008Jerome Kagan The balance between the preservation of early cognitive functions and serious transformations on these functions shifts across time. Piaget's writings, which favored transformations, are being replaced by writings that emphasize continuities between select cognitive functions of infants and older children. The claim that young infants possess elements present in the older child's concepts of number, physical impossibility, and object permanence is vulnerable to criticism because the inferences are based primarily on the single measure of change in looking time. It is suggested that investigators use unique constructs to describe phenomena observed in young infants that appear, on the surface, to resemble the psychological competences observed during later developmental stages. [source] New developments in our understanding of acne pathogenesis and treatmentEXPERIMENTAL DERMATOLOGY, Issue 10 2009Ichiro Kurokawa Abstract:, Interest in sebaceous gland physiology and its diseases is rapidly increasing. We provide a summarized update of the current knowledge of the pathobiology of acne vulgaris and new treatment concepts that have emerged in the last 3 years (2005,2008). We have tried to answer questions arising from the exploration of sebaceous gland biology, hormonal factors, hyperkeratinization, role of bacteria, sebum, nutrition, cytokines and toll-like receptors (TLRs). Sebaceous glands play an important role as active participants in the innate immunity of the skin. They produce neuropeptides, excrete antimicrobial peptides and exhibit characteristics of stem cells. Androgens affect sebocytes and infundibular keratinocytes in a complex manner influencing cellular differentiation, proliferation, lipogenesis and comedogenesis. Retention hyperkeratosis in closed comedones and inflammatory papules is attributable to a disorder of terminal keratinocyte differentiation. Propionibacterium acnes, by acting on TLR-2, may stimulate the secretion of cytokines, such as interleukin (IL)-6 and IL-8 by follicular keratinocytes and IL-8 and -12 in macrophages, giving rise to inflammation. Certain P. acnes species may induce an immunological reaction by stimulating the production of sebocyte and keratinocyte antimicrobial peptides, which play an important role in the innate immunity of the follicle. Qualitative changes of sebum lipids induce alteration of keratinocyte differentiation and induce IL-1 secretion, contributing to the development of follicular hyperkeratosis. High glycemic load food and milk may induce increased tissue levels of 5,-dihydrotestosterone. These new aspects of acne pathogenesis lead to the considerations of possible customized therapeutic regimens. Current research is expected to lead to innovative treatments in the near future. [source] The influence of synthetic sheep urine on ammonia oxidizing bacterial communities in grassland soilFEMS MICROBIOLOGY ECOLOGY, Issue 3 2006Shahid Mahmood Abstract In grazed, grassland soils, sheep urine generates heterogeneity in ammonia concentrations, with potential impact on ammonia oxidizer community structure and soil N cycling. The influence of different levels of synthetic sheep urine on ammonia oxidizers was studied in grassland soil microcosms. ,Total' and active ammonia oxidizers were distinguished by comparing denaturing gradient gel electrophoresis (DGGE) profiles following PCR and RT-PCR amplification of 16S rRNA gene fragments, targeting DNA and RNA, respectively. The RNA-based approach indicated earlier, more reproducible and finer scale qualitative shifts in ammonia oxidizing communities than DNA-based analysis, but led to amplification of a small number of nonammonia oxidizer sequences. Qualitative changes in RNA-derived DGGE profiles were related to changes in nitrate accumulation. Sequence analysis of excised DGGE bands revealed that ammonia oxidizing communities in synthetic sheep urine-treated soils consisted mainly of Nitrosospira clusters 2, 3 and 4. Nitrosospira cluster 2 increased in relative abundance in microcosms treated with all levels of synthetic sheep urine. Low levels additionally led to increased relative abundance of Nitrosospira cluster 4 and medium and high levels increased relative abundance of cluster 3. Synthetic sheep urine is therefore likely to influence the spatial distribution and composition of ammonia oxidizer communities, with consequent effects on nitrate accumulation. [source] Dehydroepiandrosterone regulates astroglia reaction to denervation of olfactory glomeruliGLIA, Issue 3 2004Zsófia Hoyk Abstract Effects of dehydroepiandrosterone (DHEA) on glial reactions of the peripherally denervated olfactory bulb were studied in adult male rats. Denervation was achieved by destroying the olfactory mucosa with ZnSO4 (0.17 M) irrigation of the nasal cavities. In one series of experiments, chronic DHEA treatment was applied (daily injections for 7 days, i.p., 10 mg/kg b.w. and 25 mg/kg b.w.); in the other series of experiments, animals received a single injection of DHEA (i.p., 10 mg/kg b.w., 25 mg/kg b.w. and 50 mg/kg b.w.) 2 h following ZnSO4 treatment. To determine whether DHEA conversion to estradiol was involved in the mechanism of DHEA action on glia, a third series of experiments was carried out in which the aromatase inhibitor fadrozole (4.16 mg/ml) was administered using subcutaneously implanted osmotic minipumps. Rats were killed on day 7 after chemical denervation, and the reaction of glial cells was monitored within the olfactory bulb, using GFAP and vimentin immunohistochemistry. Qualitative changes in GFAP expression were analyzed by Western blot. Chronic DHEA treatment with both doses (10 mg/kg b.w. and 25 mg/kg b.w.) and acute DHEA treatment with the highest dose applied (50 mg/kg b.w.), inhibited the increase in GFAP expression induced by the denervation of the olfactory bulb. Furthermore, GFAP and vimentin immunostaining in the glomerular layer of the olfactory bulb were diminished in the denervated and DHEA treated groups. However, when DHEA treatment was combined with fadrozole administration, such a decrease in GFAP expression could not be detected in the chemically denervated olfactory bulb. These findings indicate that DHEA, depending on the dose applied and the mode of administration, attenuates glial reaction to denervation and may regulate glial plasticity in the olfactory glomeruli. These effects are likely to be mediated at least in part by the conversion of DHEA to estradiol. © 2004 Wiley-Liss, Inc. [source] Effect of molecular weight, temperature, and additives on the moisture sorption properties of polyethylene glycolJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 1 2010Jared A. Baird Abstract Polyethylene glycol (PEG) is a hygroscopic polymer that undergoes the phenomenon of deliquescence once a critical relative humidity (RH0) is reached. The purpose of this study was to test the hypothesis that the deliquescence behavior of PEG will be affected by the polymer molecular weight, temperature, and the presence of additives. The deliquescence relative humidity for single component (RH0) and binary mixtures (RH0,mix) were measured using an automated gravimetric moisture analyzer at 25 and 40°C. Changes in PEG crystallinity after exposure to moisture were qualitatively assessed using powder X-ray diffraction (PXRD). Optical microscopy was used to visually observe the deliquescence phenomenon. For single component systems, decreasing PEG MW and elevating the temperature resulted in a decrease in the observed RH0. Physical mixtures of acetaminophen and anhydrous citric acid with both PEG 3350 and PEG 100,000 exhibited deliquescence (RH0,mix) at a relative humidity below that of either individual component. Qualitative changes in crystallinity were observed from the X-ray diffractograms for each PEG MW grade at high relative humidities, indicating that phase transformation (deliquescence) of the samples had occurred. In conclusion, it was found that the deliquescence behavior of PEG was affected by the polymer MW, temperature, and the presence of additives. This phenomenon may have important implications for the stability of PEG containing formulations. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:154,168, 2010 [source] Effective radial Liapunov exponent for the radial diffusion of test electronsCONTRIBUTIONS TO PLASMA PHYSICS, Issue 3-4 2003A. Maluckov Abstract The radial diffusion of test electrons in the bounded magnetic field region with irregularities is a realization of the magnetic (deterministic) and collisional (statistical) stochasticities. To clarify the development of stochasticities the effective radial Liapunov exponent Ler, the number of the electron trajectories (magnetic field lines) with positive radial Liapunov exponent Np, the distribution of the radial Liapunov exponent, Kolmogorov entropy and 3D Liapunov exponent are calculated numerically. In the absence of collisions the overlapping among magnetic islands (generation of the global stochasticity) is indicated by the qualitative change from negative to positive Ler in the long time limit. The fact that Np < N, where N is the number of test electrons, is the sign of sticking to the magnetic field structures. From the viewpoint of the radial Liapunov exponents both stochasticities manifest similarly. It is shown that the distribution of the radial Liapunov exponents is not the elementary one, except in the region of the extremely frequent collisions and partially destroyed magnetic field. Transition of the radial diffusion from the strange to the standard diffusion [1] is related with neglecting sticking of the electrons to the magnetic field structures by enough frequent collisions. [source] What the eyes already ,know': using eye movement measurement to tap into children's implicit numerical magnitude representationsINFANT AND CHILD DEVELOPMENT, Issue 2 2010Angela Heine Abstract To date, a number of studies have demonstrated the existence of mismatches between children's implicit and explicit knowledge at certain points in development that become manifest by their gestures and gaze orientation in different problem solving contexts. Stimulated by this research, we used eye movement measurement to investigate the development of basic knowledge about numerical magnitude in primary school children. Sixty-six children from grades one to three (i.e. 6,9 years) were presented with two parallel versions of a number line estimation task of which one was restricted to behavioural measures, whereas the other included the recording of eye movement data. The results of the eye movement experiment indicate a quantitative increase as well as a qualitative change in children's implicit knowledge about numerical magnitudes in this age group that precedes the overt, that is, behavioural, demonstration of explicit numerical knowledge. The finding that children's eye movements reveal substantially more about the presence of implicit precursors of later explicit knowledge in the numerical domain than classical approaches suggests further exploration of eye movement measurement as a potential early assessment tool of individual achievement levels in numerical processing. Copyright © 2009 John Wiley & Sons, Ltd. [source] The Socio-spatial Conditions of the Open City: A Theoretical SketchINTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 3 2005DETLEV IPSEN Without additional immigration of several million people over the next few decades, the demographic development of most European countries will lead to a considerable population decrease. Because such a reduction is neither desirable nor realistically possible, cities in particular will be the target of increasing immigration, and hence will undergo qualitative change. Today, there are large ethnic and cultural minorities in many German cities and suburbs; in the future, whole cities will become international, and suburbs will become ethnic-cultural communities. This article presents a theory for the discussion on how such a change can be managed productively. The concept of the ,open city' is understood as both a risk and an opportunity. This article pleads for a socio-culturally segregated division of urban space for the prevention of discrimination to be possible. The multitude of separate cultures must be supplemented by a ,hyper-culture' in order to integrate the urban culture as a whole. Sans l'apport de l'immigration de plusieurs millions de personnes au cours des prochaines décennies, l'évolution démographique de la plupart des pays d'Europe aboutira à une nette chute de population. Comme une telle diminution n'est ni souhaitable ni une réalité envisageable, les villes notamment vont être la cible d'une immigration croissante, donc subir des changements qualitatifs. Aujourd'hui, il existe d'importantes minorités ethniques et culturelles dans de nombreuses villes et banlieues allemandes: à l'avenir, la totalité des villes deviendront internationales et les banlieues se feront communautés ethno-culturelles. Cet article présente une théorie comme base de discussion sur la manière de gérer ce changement de façon productive. Le concept de ,ville ouverte' est perçu à la fois comme un risque et une opportunité. L'article plaide pour une division socio-culturelle de l'espace urbain comme moyen de prévention de la discrimination. La multitude de cultures distinctes doit être complétée d'une ,hyper-culture' afin d'intégrer en bloc la culture urbaine. [source] Predicting the effects of perturbations on ecological communities: what can qualitative models offer?JOURNAL OF ANIMAL ECOLOGY, Issue 5 2005DAVE RAMSEY Summary 1Quantitative predictions of the effects of perturbations on communities of interacting species have often proved to be difficult. However, if precise predictions are not a requirement then qualitative models of community dynamics offer an alternative method for predicting species responses to perturbations. 2We used two qualitative modelling approaches to predict the effects of predator control on the fledging rate of an endangered New Zealand bird, the North Island kokako. The first approach was based on loop analysis and provided predictions on the probable direction of change in species abundances to single species perturbations. The second approach, ,fuzzy interaction webs', used fuzzy logic in the framework of a fuzzy cognitive map to provide predictions on the probable magnitude of change in species abundances to perturbations. 3Using both methods, we predicted the qualitative change in the equilibrium fledging rates of kokako under various regimes of single- and multispecies predator control (ship rats, brushtail possums and stoats). Single species control was insufficient to lift the fledging rate from ,low' to ,moderate'. However, simultaneous control of both ship rats and possums had the greatest influence on the fledging rates compared with any other combination as a result of the additional indirect effect of ship rat control on stoat abundance. 4We propose qualitative modelling of community dynamics as a method suitable for predicting the effects of perturbations in complex ecological communities that can encapsulate diverse sources of knowledge about food web interactions. We believe that these methods are a useful set of heuristic tools that can be used to propose testable hypotheses about ecosystem functioning that can complement existing statistical and quantitative modelling approaches. [source] [2,+,3] Cycloaddition of C,C,N -triphenylnitrone to trans -substituted nitroethylenes in the light of an AM1 and AM1/COSMO computational study,JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 5 2003Andrzej Baranski Abstract AM1 calculations suggest that the [2,+,3] cycloaddition of triphenylnitrone 1 to nitroalkenes 2a,c in the gas phase takes place in a concerted manner. However, the azolidine ring bonds C3,C4 and O1,C5 are not formed fully synchronously. Kinetic factors favor the formation of cycloadducts with nitro group in position C-4 of the azolidine ring (path A). Introduction of toluene, acetone or acetonitrile as a reaction medium increases the activation barriers for both regioisomeric paths. Simultaneously, the energy profiles for path A undergo qualitative change. In this case, two transition states and an intermediate with zwitterionic character were localized by means of the AM1/COSMO method. Copyright © 2003 John Wiley & Sons, Ltd. [source] Influence of the cross-linking density on the main dielectric relaxation of poly(methyl acrylate) networksPOLYMER ENGINEERING & SCIENCE, Issue 10 2005J.M. Meseguer Dueñas A series of polymer networks of varying cross-linking density was prepared by copolymerization of methyl acrylate and ethyleneglycol dimethacrylate. The aim of this work is to study the influence of cross-linking on the conformational mobility of the polymer chains using dielectric relaxation spectroscopy (DRS) in the temperature range of the main dielectric relaxation. As expected, the temperature range in which glass transition takes place became wider with increasing crosslinking density. DRS results were analyzed using the Havriliak-Negami equation. Master Cole-Cole arcs could be drawn for all the networks. The arcs become more symmetric as cross-linking density increases, as a consequence of the different effect of cross-links on large and small scale mobility. The conformational mobility that produces the main relaxation is drastically reduced when the cross-linking density increases what reduces the relaxation strength, but it also gives a qualitative change of behavior, as shown by the temperature dependence of the relaxation strength. In the loosely cross-linked networks the relaxation strength decreases monotonously as temperature increases, as in the main dielectric relaxation of linear polymers. Nevertheless, in highly cross-linked networks the curve of relaxation strength against temperature presents a maximum. POLYM. ENG. SCI., 45:1336,1342, 2005. © 2005 Society of Plastics Engineers [source] Epitope-specific immunotherapy of rheumatoid arthritis: Clinical responsiveness occurs with immune deviation and relies on the expression of a cluster of molecules associated with T cell tolerance in a double-blind, placebo-controlled, pilot phase II trial,ARTHRITIS & RHEUMATISM, Issue 11 2009Eva C. Koffeman Objective Induction of immune tolerance to maintain clinical control with a minimal drug regimen is a current research focus in rheumatoid arthritis (RA). Accordingly, we are developing a tolerization approach to dnaJP1, a peptide part of a pathogenic mechanism that contributes to autoimmune inflammation in RA. We undertook this study to test 2 hypotheses: 1) that mucosal induction of immune tolerance to dnaJP1 would lead to a qualitative change from a proinflammatory phenotype to a more tolerogenic functional phenotype, and 2) that immune deviation of responses to an inflammatory epitope might translate into clinical improvement. Methods One hundred sixty patients with active RA and with immunologic reactivity to dnaJP1 were enrolled in a pilot phase II trial. They received oral doses of 25 mg of dnaJP1 or placebo daily for 6 months. Results The dnaJP1 peptide was safe and well-tolerated. In response to treatment with dnaJP1, there was a significant reduction in the percentage of T cells producing tumor necrosis factor , and a corresponding trend toward an increased percentage of T cells producing interleukin-10. Coexpression of a cluster of molecules (programmed death 1 and its ligands) associated with T cell regulation was also found to be a prerequisite for successful tolerization in clinical responders. Analysis of the primary efficacy end point (meeting the American College of Rheumatology 20% improvement criteria at least once on day 112, 140, or 168) showed a difference between treatment groups that became significant in post hoc analysis using generalized estimating equations. Differences in clinical responses were also found between treatment groups on day 140 and at followup. Post hoc analysis showed that the combination of dnaJP1 and hydroxychloroquine (HCQ) was superior to the combination of HCQ and placebo. Conclusion Tolerization to dnaJP1 leads to immune deviation and a trend toward clinical efficacy. Susceptibility to treatment relies on the coexpression of molecules that can down-regulate adaptive immunity. [source] Oral cimetidine gives effective symptom relief in painful bladder disease: a prospective, randomized, double-blind placebo-controlled trialBJU INTERNATIONAL, Issue 3 2001R. Thilagarajah Objective To evaluate the efficacy of oral cimetidine as a treatment for painful bladder disease (PBD, variously described as a ,symptom complex' of suprapubic pain, frequency, dysuria and nocturia in the absence of overt urine infection) by assessing symptom relief and histological changes in the bladder wall tissue components, compared with placebo. Patients and methods The study comprised 36 patients with PBD enrolled into a double-blind clinical study with two treatment arms, i.e. oral cimetidine or placebo, for a 3-month trial. Patients were asked to complete a symptom questionnaire (maximum score 35), and underwent cystoscopy and bladder biopsy before treatment allocation. On completing treatment the patients were re-evaluated by the questionnaire and biopsy. The symptom scores and bladder mucosal histology were compared before and after treatment, and the results analysed statistically to assess the efficacy of cimetidine. Results Of the 36 patients recruited, 34 (94%) completed the study. Those receiving cimetidine had a significant improvement in symptoms, with median symptom scores decreasing from 19 to 11 (P < 0.001). Suprapubic pain and nocturia decreased markedly (P = 0.009 and 0.006, respectively). However, histologically the bladder mucosa showed no qualitative change in the glycosaminoglycan layer or basement membrane, or in muscle collagen deposition, in either group. The T cell infiltrate was marginally decreased in the cimetidine group (median 203 before and 193 after) and increased in the placebo group (median 243 and 250, P > 0.3 and > 0.2, respectively). Angiogenesis remained relatively unchanged. The incidence of mast cells and B cells was sporadic in both groups. Conclusions Oral cimetidine is very effective in relieving symptoms in patients with PBD but there is no apparent histological change in the bladder mucosa after treatment; the mechanism of symptom relief remains to be elucidated. [source] Epidermal kinetic alterations required to generate the psoriatic phenotype: a reappraisalCELL PROLIFERATION, Issue 3 2010T. Simonart Objectives:, Although there have been major advances in understanding immunopathogenesis of psoriasis, the basic processes causing psoriatic morphology remain to be identified. Materials and methods:, Our group has designed a systematic review of studies (1962,2009) on keratinocyte kinetics in psoriasis. We obtained data from MEDLINE, PubMed, Current Contents, reference lists and specialist textbooks. A general equation for evolution of the differentiated epidermis has been analysed. Necessary conditions for observed qualitative change in homeostasis between normal skin and established psoriatic lesions were determined. Results and discussion:, Increase in the number of cell divisions (or imbalance in symmetric division rates of committed progenitor cells) and/or decrease in physiological apoptosis in the germinative compartment, together with feedback loops that limit thickening of the skin, are required to generate psoriatic morphology, that is, to increase the absolute size but decrease relative size of the differentiated cell compartment with respect to the germinative compartment. [source] Continuities and Discontinuities in Children and ScholarshipCHILD DEVELOPMENT, Issue 6 2008Lynn S. Liben This article introduces a collection of essays on continuity and discontinuity in cognitive development. In his lead essay, J. Kagan (2008) argues that limitations in past research (e.g., on number concepts, physical solidarity, and object permanence) render conclusions about continuity premature. Commentaries respectively (1) argue that longitudinal contexts are essential for interpreting developmental data, (2) illustrate the value of converging measures, (3) identify qualitative change via dynamical systems theory, (4) redirect the focus from states to process, and (5) review epistemological premises of alternative research traditions. Following an overview of the essays, this introductory article discusses how the search for developmental structures, continuity, and process differs between mechanistic-contextualist and organismic-contextualist metatheoretical frameworks, and closes by highlighting continuities in Kagan's scholarship over the past half century. [source] Threshold electrical stimulation (TES) in ambulant children with CP: a randomized double-blind placebo-controlled clinical trialDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 6 2002Christineí Dali MD A randomized double-blind placebo-controlled clinical trial was carried out to determine whether a group of stable children with cerebral palsy (36 males, 21 females; mean age 10 years 11 months, range 5 to 18 years) would improve their motor skills after 12 months of threshold electrical stimulation (TES). Two thirds received active and one third received inactive stimulators. For the primary outcome we constructed a set of plausible motor function tests and studied the change in summary indices of the performance measurements. Tests were videotaped and assessed blindly to record qualitative changes that might not be reflected in performance measurements. We also judged range of motion, degree of spasticity, and muscle growth measured by CT. Fifty seven of 82 outpatients who were able to walk at least with a walker, completed all 12 months of treatment (hemiplegia n=25, diplegia n=32). There was no significant difference between active and placebo treatment in any of the tested groups, nor combined. Visual and subjective assessments favoured TES (ns), whereas objective indices showed the opposite trend. We conclude that TES in these patients did not have any significant clinical effect during the test period. [source] Using Rock-Eval 6 pyrolysis for tracking fossil organic carbon in modern environments: implications for the roles of erosion and weatheringEARTH SURFACE PROCESSES AND LANDFORMS, Issue 2 2006Yoann Copard Abstract This work relates to the debate on the fossil organic carbon (FOC) input in modern environments and its possible implication for the carbon cycle, and suggests the use of Rock-Eval 6 pyrolysis as a relevant tool for tracking FOC in such environments. Considering that such a delivery is mainly due to supergene processes affecting the continental surface, we studied organic matter in different reservoirs such as bedrocks, alterites, soils and rivers in two experimental catchments at Draix (Alpes de Haute Provence, France). Samples were subjected to geochemical (Rock-Eval 6 pyrolysis) investigations and artificial bacterial degradations. After comparing the geochemical fingerprint of samples, geochemical markers of FOC were defined and tracked in the different reservoirs. Our results confirm the contribution of FOC in modern soils and rivers and display the various influences of weathering and erosional processes on the fate of FOC during its exchange between these pools. In addition, the contrasting behaviour of these markers upon the supergene processes has also highlighted the refractory or labile characters of the fossil organic matter (FOM). Bedrock to river fluxes, controlled by gully erosion, are characterized by a qualitative and quantitative preservation of FOM. Bedrock to alterite fluxes, governed by chemical weathering, are characterized by FOC mineralization without qualitative changes in deeper alterites. Alterite to soils fluxes, controlled by (bio)chemical weathering, are characterized by strong FOC mineralization and qualitative changes of FOM. Thus weathering and erosional processes induce different FOM evolution and affect the fate of FOC towards the global carbon cycle. In this study, gully erosion would involve maintenance of an ancient sink for the global carbon cycle, while (bio)chemical processes provide a source of CO2. Finally, this study suggests that Rock-Eval 6 pyrolysis can be considered as a relevant tool for tracking FOC in modern environments. Copyright © 2006 John Wiley & Sons, Ltd. [source] Effect kinetics of desmopressin-induced platelet retention in healthy volunteers treated with aspirin or placeboHAEMOPHILIA, Issue 1 2000Lethagen Desmopressin is often used for haemostatic treatment in platelet dysfunction, but the effect kinetics of platelet responses and the mechanism of action are poorly known. This study aimed to determine the kinetics of platelet function responses induced by desmopressin in healthy volunteers treated with aspirin or placebo. Another aim was to correlate platelet responses to changes of von Willebrand factor (vWF) in plasma. We measured platelet function with a glass bead retention test, Ivy bleeding time, vWF:Ag and multimeric structure in plasma. Median baseline platelet retention was 12% (normal reference range 16,27%) during aspirin treatment and 18% during placebo. Median peak platelet retention after desmopressin was 33% during aspirin treatment and 34% during placebo. After about 3 h platelet function had returned to baseline. A second desmopressin dose after 3 h stimulated platelet retention to a similar extent as the first dose. There was no correlation between platelet responses and quantitative or qualitative changes of vWF in plasma. Platelet count did not change significantly. Thus, desmopressin's effect on platelet function lasts for about 3 h, but may be prolonged by a second dose immediately thereafter. These findings may have important clinical implications for patients with aspirin-induced platelet dysfunction undergoing surgery. [source] Innovation and transportation's technologiesJOURNAL OF ADVANCED TRANSPORTATION, Issue 1 2000Article first published online: 19 JAN 2010, William L. Garrison I critique the innovation processes that yield transportation's technologies, and to aid my analysis I look back to take advantage of the accumulation of experiences and insights marked by the millennium. I identify supply, transport, and user systems. Transport systems move things; supply systems provide fuel, pavements, and other inputs to transport activities; and user systems combine transport with other activities for socially useful purposes. The discussion then shifts from structure to behavior, and a short review of the emergence of today's systems reminds us that technological advances may improve the provision of old services, offer new ways of doing old things, or induce qualitative changes that enable doing new things. With these structural and behavioral matters in mind, I challenge the reader to judge the present situation and the future. [source] Bacterial flora in irritable bowel syndrome: role in pathophysiology, implications for managementJOURNAL OF DIGESTIVE DISEASES, Issue 1 2007Eamonn M M QUIGLEY Irritable bowel syndrome (IBS) may, in part at least, result from a dysfunctional interaction between the indigenous flora and the intestinal mucosa which, in turn, leads to immune activation in the colonic mucosa. Some propose a role for bacterial overgrowth as a common causative factor in the pathogenesis of symptoms in IBS; other evidence points to more subtle qualitative changes in the colonic flora; both hypotheses remain to be confirmed but the likelihood that bacterial overgrowth will prove to be a major factor in IBS now seems remote. Nevertheless, short-term therapy with either antibiotics or probiotics does seem to reduce symptoms among IBS patients. It seems most likely that the benefits of antibiotic therapy are mediated through subtle and, perhaps, localized, quantitative and/or qualitative changes in the colonic flora. How probiotics exert their effects remain to be defined but an anti-inflammatory effect seems likely. While this approach to the management of IBS is in its infancy, it is evident that manipulation of the flora, whether through the administration of antibiotics or probiotics, deserves further attention in IBS. [source] Calman,Hine reassessed: a survey of cancer network development in England, 1999,2000JOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 3 2002Beth Kewell BA PhD Abstract Rationale, aims and objectives,The paper assesses preliminary national data on the development of cancer care networks in England. Methods,In January 2000, a national postal survey was sent to lead clinicians at 36 cancer centres and associate centres. Respondents were asked to provide basic numerical data on the design of the network (i.e. its configuration), detailing how many units it encompassed, and whether the centre was a multiple or a single entity. Results,The survey highlighted national variations in the size and configuration of networks. The survey also highlighted tentative signs of shifts in clinical practice. The results showed that consultants at cancer centres and units were engaging in two forms of collaboration across centre,unit boundaries. Type 1 involved routine multidisciplinary team (MDT) outreach from centres to units, incorporating joint planning between clinicians at cancer centres and cancer units. Type 2 collaboration involved joint planning but also promoted joint centre and unit training and continuing professional development (CPD) programmes. Conclusions,In our estimation, both forms of collaboration represented early evidence of qualitative changes in medical working practices. Organizational changes within cancer services have moved swiftly since initial soundings were taken in 2000 and we update our initial commentary in the light of recent empirical data. The findings may be of wider significance to managers and health practitioners who are working towards the implementation of delivery network elsewhere in the UK National Health Service. [source] Delayed kinetics of DNA double-strand break processing in normal and pathological agingAGING CELL, Issue 1 2008Olga A. Sedelnikova Summary Accumulation of DNA damage may play an essential role in both cellular senescence and organismal aging. The ability of cells to sense and repair DNA damage declines with age. However, the underlying molecular mechanism for this age-dependent decline is still elusive. To understand quantitative and qualitative changes in the DNA damage response during human aging, DNA damage-induced foci of phosphorylated histone H2AX (,-H2AX), which occurs specifically at sites of DNA double-strand breaks (DSBs) and eroded telomeres, were examined in human young and senescing fibroblasts, and in lymphocytes of peripheral blood. Here, we show that the incidence of endogenous ,-H2AX foci increases with age. Fibroblasts taken from patients with Werner syndrome, a disorder associated with premature aging, genomic instability and increased incidence of cancer, exhibited considerably higher incidence of ,-H2AX foci than those taken from normal donors of comparable age. Further increases in ,-H2AX focal incidence occurred in culture as both normal and Werner syndrome fibroblasts progressed toward senescence. The rates of recruitment of DSB repair proteins to ,-H2AX foci correlated inversely with age for both normal and Werner syndrome donors, perhaps due in part to the slower growth of ,-H2AX foci in older donors. Because genomic stability may depend on the efficient processing of DSBs, and hence the rapid formation of ,-H2AX foci and the rapid accumulation of DSB repair proteins on these foci at sites of nascent DSBs, our findings suggest that decreasing efficiency in these processes may contribute to genome instability associated with normal and pathological aging. [source] Five-year prospective analysis of dietary intake and clinical status in malnourished cystic fibrosis patientsJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 4 2003J. Walkowiak Abstract Background, Poor growth and malnutrition still pose a problem in cystic fibrosis (CF). The aim of the present study was to assess nutrition, as well as clinical status, of malnourished CF patients during a nutritional care programme. Material and methods, The study comprised 38 CF patients, aged 1,18 years old. The prospective annual assessment of dietary intake and clinical status was carried out during 1994,98. Results, The energy intake increased, in comparison with recommended daily allowances, from 83.6 ± 4.8% in 1994 to 107.9 ± 4.9% in 1998. A similar tendency was observed for the percentage of energy derived from fat (30.3 ± 0.8% versus 35.1 ± 0.8%) and protein (11.4 ± 0.4% versus 13.8 ± 0.4%). In subsequent years of the study, an improvement in the fat profile of the diet (with a higher consumption of polyunsaturated fatty acids) was observed. The observed increase of vitamin A and E consumption was related chiefly to changes in the doses of supplementation. During these 5 years, an improvement in nutritional status (Z-score: height ,1.34 ± 0.13 versus ,1.08 ± 0.14 and weight ,1.40 ± 0.09 versus ,1.12 ± 0.08) and lung function (forced expiratory volume in 1 s: 75.5 ± 2.0% versus 77.8 ± 2.2%) was observed. Conclusion, The nutritional care programme resulted in stable quantitative and qualitative changes in dietary intake. Although the diet does not reach the recommended level of high-energy intake, the positive impact of increasing nutrient intake on the nutritional and clinical status of malnourished CF patients was documented. [source] Phosphatidylethanol Mediates its Effects on the Vascular Endothelial Growth Factor via HDL Receptor in Endothelial CellsALCOHOLISM, Issue 2 2009Marja Katriina Liisanantti Background:, Previous epidemiological studies have shown that light to moderate alcohol consumption has protective effects against coronary heart disease but the mechanisms of the beneficial effect of alcohol are not known. Ethanol may increase high density lipoprotein (HDL) cholesterol concentration, augment the reverse cholesterol transport, or regulate growth factors or adhesion molecules. To study whether qualitative changes in HDL phospholipids mediate part of the beneficial effects of alcohol on atherosclerosis by HDL receptor, we investigated whether phosphatidylethanol (PEth) in HDL particles affects the secretion of vascular endothelial growth factor (VEGF) by a human scavenger receptor CD36 and LIMPII analog-I (CLA-1)-mediated pathway. Methods:, Human EA.hy 926 endothelial cells were incubated in the presence of native HDL or PEth-HDL. VEGF concentration and CLA-1 protein expression were measured. Human CLA-1 receptor-mediated mechanisms in endothelial cells were studied using CLA-1 blocking antibody and protein kinase inhibitors. Results:, Phosphatidylethanol-containing HDL particles caused a 6-fold increase in the expression of CLA-1 in endothelial cells compared with the effect of native HDL. That emergent effect was mediated mainly through protein kinase C and p44/42 mitogen-activated protein kinase pathways. PEth increased the secretion of VEGF and that increase could be abolished by a CLA-1 blocking antibody. Conclusions:, High density lipoprotein particles containing PEth bind to CLA-1 receptor and thereby increase the secretion of VEGF from endothelial cells. Ethanol-induced protective effects against coronary heart disease may be explained, at least partly, by the effects of PEth-modified HDL particles on VEGF via CLA-1-mediated mechanisms in endothelial cells. [source] Correlated changes in skeletal muscle connective tissue and flesh texture during starvation and re-feeding in brown trout (Salmo trutta) reared in seawaterJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 11 2004Jérôme Bugeon Abstract Quantitative and qualitative changes to muscle and collagen were analysed following starvation and re-feeding of brown trout (Salmo trutta) reared in seawater. Fish were submitted to starvation for 2 months followed by re-feeding for 1 month and compared with a control group continuously fed. Classical effects of starvation on growth and morphometrics traits were observed with only a partial recovery of these parameters after 1 month of re-feeding. Muscle composition of starved fish was significantly affected (lower dry matter content and higher post-mortem pH) compared with control fish and was partially recovered in re-fed fish compared with continuously fed fish. Muscle structure and composition were affected with thinner muscle fibre and higher connective tissue content for the starved fish but similar thickness of myosepta compared with the control group. No difference was observed after 1 month of re-feeding. Characteristics of the connective tissue were significantly affected by starvation (more high weight molecular collagen form, higher thermal stability of skin collagen). These differences remained significant after the re-feeding period. Starved fish showed also higher mechanical resistance of the raw flesh compared with the control group, but no difference in rheological measurements was observed after 1 month of re-feeding. The changes in texture and their relationships with muscle composition, muscle structure and collagen characteristics are discussed. Copyright © 2004 Society of Chemical Industry [source] Influence of Starvation on Flesh Quality of Farmed Dentex, Dentex dentexJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 4 2010María Dolores Suárez Dentex (mean initial weight 324 ± 5 g) from a fish farm were divided into two groups (control and fasted). At the end of experimental period (5 wk), dentex were sampled for gross muscle composition and quality analysis. For post mortem muscle analysis, after death, fish were kept in a cold chamber at 4 C, and muscle samples were taken at 4 (prerigor state), 24 (rigor state), and 82 (postrigor state) h after slaughtering. In each fish, textural and biochemical parameters were determined. During starvation, there was a drastic reduction in muscle lipid content and a relative increase of the proteolysis. There were little qualitative changes in the fatty-acid profile of muscle lipids, although a significant increase in n3/n6 ratio in the starved dentex was detected. Starved fish also showed higher muscle firmness, but no differences in pH and water holding capacity were observed. Total and myofibrillar protein and collagen content increased significantly in starved dentex. Firmness during post mortem storage was significantly higher in starved fish, compared with control group. Preslaughtering feeding status showed decisive influence on the evolution dentex muscle quality parameters during cold storage. [source] Role of Lung Surfactant in Respiratory Disease: Current Knowledge in Large Animal MedicineJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 2 2009U. Christmann Lung surfactant is produced by type II alveolar cells as a mixture of phospholipids, surfactant proteins, and neutral lipids. Surfactant lowers alveolar surface tension and is crucial for the prevention of alveolar collapse. In addition, surfactant contributes to smaller airway patency and improves mucociliary clearance. Surfactant-specific proteins are part of the innate immune defense mechanisms of the lung. Lung surfactant alterations have been described in a number of respiratory diseases. Surfactant deficiency (quantitative deficit of surfactant) in premature animals causes neonatal respiratory distress syndrome. Surfactant dysfunction (qualitative changes in surfactant) has been implicated in the pathophysiology of acute respiratory distress syndrome and asthma. Analysis of surfactant from amniotic fluid allows assessment of fetal lung maturity (FLM) in the human fetus and exogenous surfactant replacement therapy is part of the standard care in premature human infants. In contrast to human medicine, use and success of FLM testing or surfactant replacement therapy remain limited in veterinary medicine. Lung surfactant has been studied in large animal models of human disease. However, only a few reports exist on lung surfactant alterations in naturally occurring respiratory disease in large animals. This article gives a general review on the role of lung surfactant in respiratory disease followed by an overview of our current knowledge on surfactant in large animal veterinary medicine. [source] Studies on dimerisation of tocopherols under the influence of methyl linoleate peroxidesMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 2 2003Marek Gogolewski Abstract The stability of plant oils is related to the level of polyunsaturated fatty acids and the presence of native antioxidants , especially tocopherols. During storage, lipids or the fat products undergo oxidation and tocopherol dimers and trimers are formed. These compounds possess reducing and antioxidant properties and participate in oxidation clearly inhibiting this process. In the present study, the correlation between levels of peroxides formed during autoxidation of methyl linoleate and simultaneous decomposition of tocopherols was examined. The peroxide value was investigated. Quantities of decomposed tocopherols and formation of their dimers were determined by high-performance liquid chromatography (HPLC). Mass spectrum analysis confirmed that the analysed compounds were dimers. Dimerisation of ,-T begins at the smaller quantity of the methyl linoleate peroxides than dimerisation of ,-T. At the beginning of methyl linoleate autoxidation dimerization of ,-T in relation to its loss was smaller. The quantity of ,-T dimers with ether bonds in total dimers pointed to faster binding of phenoxy radicals than transformation into the phenyl ones. ,-T dimers with phenyl bonds constitute about 65% of the total. The quantity of peroxides in methyl linoleate, necessary for quantitative and qualitative changes of homologous tocopherols, decreased from ,-T to ,-T. [source] Altered intestinal microbiota in irritable bowel syndromeNEUROGASTROENTEROLOGY & MOTILITY, Issue 5 2010K. J. Lee Abstract, Recent studies have suggested that alterations in the composition of the intestinal microbiota may play an important role in irritable bowel syndrome (IBS) symptoms. However, an association between the composition of the intestinal microbiota and IBS symptoms has not been clearly demonstrated. In the current issue of the Journal, Tana et al. suggest that altered intestinal microbiota contributes to the symptoms of IBS through increased levels of organic acids. In fecal samples, IBS patients had significantly higher numbers of Veillonella and Lactobacillus than healthy controls. They also showed significantly higher levels of acetic acid and propionic acid. Furthermore, IBS patients with high acetic acid or propionic acid levels presented more severe symptoms, impaired quality of life and negative emotions. These results are in accordance with the concept that the gut microbiota influences the sensory, motor and immune system of the gut and interacts with higher brain centers. Small intestinal bacterial overgrowth observed in a subset of IBS patients describes quantitative changes in the small intestinal microbiota. Data on qualitative changes in the gut microbiota in IBS patients are lacking. Different members of gut bacteria may have different influence on gut function. The concepts identified here may lead to the development of novel therapeutic strategies for IBS using manipulation of the intestinal microbiota. [source] Workplace performance,PLUS: Empowerment and voice through professional development and democratic processes in health care trainingPERFORMANCE IMPROVEMENT QUARTERLY, Issue 4 2009Kathleen P. King Based on the theory of transformative learning (Mezirow, 1980) and critical pedagogy (Freire, 1980), mixed-methods research (Tashakkori & Teddlie, 1998) of a hospital workers' union and training organization addressed the impact of a custom-designed, group-focused, results-driven professional development model with 130 participants. Employees across many job titles participated. Findings reveal substantial content learning, along with the development of empowerment and voice. The purpose of the research was to determine the ways and the extent that worker voice, satisfaction, attitude, communication, and problem solving improved as workers and managers put into practice knowledge and skills learned through the training (Winchester, 2003). The scope of results includes efficiency and skill improvements and qualitative changes intersecting professional and personal realms. [source] | |||||||||||||||||||||||||