60 resultados para Improvements in Welding Production


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PPARs are a family of nuclear hormone receptors involved in various processes that could influence ovarian function. We investigated the cellular localization and expression of PPARs during follicular development in ovarian tissue collected from rats 0, 6, 12, 24, and 48 h post-PMSG. A second group of animals received human CG (hCG) 48 h post-PMSG. Their ovaries were removed 0, 4, 8, 12, and 24 h post-hCG to study the periovulatory period. mRNAs corresponding to the PPAR isotypes (alpha, delta, and gamma) were localized by in situ hybridization. Changes in the levels of mRNA for the PPARs were determined by ribonuclease protection assays. PPAR gamma mRNA was localized primarily to granulosa cells, and levels of expression did not change during follicular development. Four hours post-hCG, levels of mRNA for PPAR gamma decreased (P < 0.05) but not uniformly in all follicles. At 24 h post-hCG, levels of PPAR gamma mRNA were reduced 64%, but some follicles maintained high expression. In contrast, mRNAs for PPAR alpha and delta were located primarily in theca and stroma, and their levels did not change during the intervals studied. To investigate the physiologic significance of PPAR gamma in the ovary, granulosa cells from PMSG-primed rats were cultured for 48 h with prostaglandin J(2) (PGJ(2)) and ciglitazone, PPAR gamma activators. Both compounds increased progesterone and E2 secretion (P < 0.05). These data suggest that PPAR gamma is involved in follicular development, has a negative influence on the luteinization of granulosa cells, and/or regulates the periovulatory shift in steroid production. The more general and steady expression of PPARs alpha and delta indicate that they may play a role in basal ovarian function.

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The efficiency of co-expression and linkage of distinct T-DNAs present in separate Agrobacterium tumefaciens was analysed in Arabidopsis thaliana transformed by the vacuum infiltration method. Co-expression was monitored by the synthesis of three bacterial proteins involved in the production of polyhydroxybutyrate (PHB) in the plastids. Out of 80 kanamycin-resistant transgenic plants analysed, 13 plants were co-transformed with the two distinct T-DNAs and produced PHB. Of those, 7 lines had a kanamycin-resistance segregation ratio consistent with the presence of a single functional insert. Genetic linkage between the distinct T-DNAs was demonstrated for all 13 PHB-producing lines, while physical linkage between the distinct T-DNAs was shown for 12 out of 13 lines. T-DNAs were frequently linked in an inverted orientation about the left borders. Transformation of A. thaliana by the co-infiltration of two A. tumefaciens containing distinct T-DNAs is, thus, an efficient approach for the integration and expression of several transgenes at a single locus. This approach will facilitate the creation and study of novel metabolic pathways requiring the expression of numerous transgenes.

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For decades, astrocytes have been regarded as passive partners of neurons in central nervous system (CNS) function. Studies of the last 20 years, however, challenged this view by demonstrating that astrocytes possess functional receptors for neurotransmitters and respond to their stimulation via release of gliotransmitters, including glutamate. Notably, astrocytes react to synaptically released neurotransmitters with intracellular calcium ([Ca(2+)]) elevations, which result in the release of glutamate via regulated exocytosis and, possibly, other mechanisms. These findings have led to a new concept of neuron-glia intercommunication where astrocytes play an unsuspected dynamic role by integrating neuronal inputs and modulating synaptic activity. The additional observation that glutamate release from astrocytes is controlled by molecules linked to inflammatory reactions, such as the cytokine tumor necrosis factor alpha (TNFalpha) and prostaglandins (PGs), suggests that glia-to-neuron signalling may be sensitive to changes in the production of these mediators occurring in pathological conditions. Indeed, a local, parenchymal brain inflammatory reaction (neuroinflammation) characterized by astrocytic and microglial activation has been reported in several neurodegenerative disorders, including AIDS dementia complex, Alzheimer's disease and amyotrophic lateral sclerosis. This transition may be accompanied by functional de-regulation and even degeneration of the astrocytes with the consequent disruption of the cross-talk normally occurring between these cells and neurons. Incorrect neuron-astrocyte interactions may be involved in neuronal derangement and contribute to disease development. The findings reported in this review suggest that a better comprehension of the glutamatergic interplay between neurons and astrocytes may provide information about normal brain function and also highlight potential molecular targets for therapeutic interventions in pathology.

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Males in many animal species differ greatly from females in morphology, physiology and behaviour. Ants, bees and wasps have a haplodiploid mechanism of sex determination whereby unfertilized eggs become males while fertilized eggs become females. However, many species also have a low frequency of diploid males, which are thought to develop from diploid eggs when individuals are homozygous at one or more sex determination loci. Diploid males are morphologically similar to haploids, though often larger and typically sterile. To determine how ploidy level and sex-locus genotype affect gene expression during development, we compared expression patterns between diploid males, haploid males and females (queens) at three developmental timepoints in Solenopsis invicta. In pupae, gene expression profiles of diploid males were very different from those of haploid males but nearly identical to those of queens. An unexpected shift in expression patterns emerged soon after adult eclosion, with diploid male patterns diverging from those of queens to resemble those of haploid males, a pattern retained in older adults. The finding that ploidy level effects on early gene expression override sex effects (including genes implicated in sperm production and pheromone production/perception) may explain diploid male sterility and lack of worker discrimination against them during development.

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The application of angiogenesis inhibitors in neurooncology is increasing. Initially, these drugs seemed to be very promising because of the surprisingly high neuroradiological response rates that were observed in first clinical trials. Meanwhile, this enthusiasm is waning, as the high response rates did not translate into substantial improvements in progression-free and overall survival. Tumor progression during or after antiangiogenic therapy is often associated with rapid clinical neurological deterioration and sometimes even with diffuse infiltrative gliomatosis-like neuroradiological phenotypes. Thus, the characterization and understanding of escape mechanisms are needed. The identification of criteria for defining the personalized use of angiogenesis inhibitors remains a challenge.

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The aim of this study was to examine the effect of an individualized overground walking interval training on gait performance [i.e., speed and energy cost (C(w))] in healthy elderly individuals. Twenty-two older adults were assigned to either a training group (TG; n=12, 73.4+/-3.9yr) or a non-training control group (CG; n=10, 70.9+/-9.6yr). TG participated in a 7-week individualized walking interval training at intensities progressing from 50 to 100% of ventilatory threshold (T (VE)). Aerobic fitness [maximal oxygen uptake (V O(2max)) and T (VE)], preferred walking speed (PWS), gross and net C(w) (GC(w) and NC(w), respectively) and relative effort (%V O(2max)) at PWS measured before training (PWS(1)) were assessed prior and following the intervention. All outcomes were measured on a treadmill. Significant improvements in GC(w) (-8%; P=0.007), NC(w) (-12%; P=0.003), relative effort (%V O(2max): -12%; P<0.001) and PWS (+12%; P<0.001) were observed in TG but not in CG (P>0.71). V O(2max) and T (VE) remained unchanged in both groups (P>0.57). Changes in GC(w) at PWS(1) (difference between GC(w) at PWS(1) measured pre and post intervention) were inversely correlated with changes in PWS (difference between pre and post PWS; r=-0.67; P=0.02). The decreased C(w) at PWS(1), with no concomitant improvement in aerobic fitness, represents the main contributing factor for the reduction of the relative effort at this speed. This also allows elderly people to increase their PWS post training. Therefore, the present walking training may be an effective way to improve walking performance and delay mobility impairment in older adults.

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INTRODUCTION: We report the impact of canakinumab, a fully human anti-interleukin-1β monoclonal antibody, on inflammation and health-related quality of life (HRQoL) in patients with difficult-to-treat Gouty Arthritis. METHODS: In this eight-week, single-blind, double-dummy, dose-ranging study, patients with acute Gouty Arthritis flares who were unresponsive or intolerant to--or had contraindications for--non-steroidal anti-inflammatory drugs and/or colchicine were randomized to receive a single subcutaneous dose of canakinumab (10, 25, 50, 90, or 150 mg) (N = 143) or an intramuscular dose of triamcinolone acetonide 40 mg (N = 57). Patients assessed pain using a Likert scale, physicians assessed clinical signs of joint inflammation, and HRQoL was measured using the 36-item Short-Form Health Survey (SF-36) (acute version). RESULTS: At baseline, 98% of patients were suffering from moderate-to-extreme pain. The percentage of patients with no or mild pain was numerically greater in most canakinumab groups compared with triamcinolone acetonide from 24 to 72 hours post-dose; the difference was statistically significant for canakinumab 150 mg at these time points (P < 0.05). Treatment with canakinumab 150 mg was associated with statistically significant lower Likert scores for tenderness (odds ratio (OR), 3.2; 95% confidence interval (CI), 1.27 to 7.89; P = 0.014) and swelling (OR, 2.7; 95% CI, 1.09 to 6.50, P = 0.032) at 72 hours compared with triamcinolone acetonide. Median C-reactive protein and serum amyloid A levels were normalized by seven days post-dose in most canakinumab groups, but remained elevated in the triamcinolone acetonide group. Improvements in physical health were observed at seven days post-dose in all treatment groups; increases in scores were highest for canakinumab 150 mg. In this group, the mean SF-36 physical component summary score increased by 12.0 points from baseline to 48.3 at seven days post-dose. SF-36 scores for physical functioning and bodily pain for the canakinumab 150 mg group approached those for the US general population by seven days post-dose and reached norm values by eight weeks post-dose. CONCLUSIONS: Canakinumab 150 mg provided significantly greater and more rapid reduction in pain and signs and symptoms of inflammation compared with triamcinolone acetonide 40 mg. Improvements in HRQoL were seen in both treatment groups with a faster onset with canakinumab 150 mg compared with triamcinolone acetonide 40 mg. TRIAL REGISTRATION: clinicaltrials.gov: NCT00798369.

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In plants, stomatal opening and closing are driven by ion fluxes that cause changes in guard cell turgor and volume, a process that is in turn regulated by complex environ¬mental and hormonal signals such as light and the phytohormone abscisic acid (ABA). With this study, we present genetic evidence that stomatal movements in response to ABA are influenced by PHOl expression in guard cells of Arabidopsis thaliana. PHOl is a phosphate exporter involved in phosphate loading into the root xylem ves¬sels and, as a result, the phol mutant is characterized by low shoot phosphate lev¬els. In leaves, PHOl was found expressed at higher level in guard cells, and was quickly up-regulated following treatment with ABA. The phol mutant was unaffected in ROS production following ABA treatment, and in stomatal movements in response to different light cues, high extracellular calcium, auxin, and fusicoccin. However, stomatal movements in response to ABA treatment were severely impaired, both in terms of induction of closure and inhibition of opening. Stomatal movements in re¬sponse to hydrogen peroxide and reduced CO2 was altered as well. Micro-grafting a phol shoot scion onto wild-type root stock resulted in plants with normal shoot growth and Pi content, but failed to restore normal stomatal response to ABA treat-ment, showing that the impairment was not a simple pleiotropic consequence of phos¬phate deficiency. PHOl knockdown using RNAi specifically in guard cells of wild-type plants caused a reduced stomatal response to ABA. In agreement, specific expression of PHOl in guard cells of phol plants complemented the mutant guard cell phenotype and re-established ABA sensitivity, although full functional complementation was co- dependent on shoot Pi sufficiency. Down-regulation of PHOl in guard cells did not alter the expression of ABA marker genes, indicating that PHOl does not affect the ABA signal transduction cascade at the transcriptional level. Together, these data reveal an important role for phosphate and PHOl action in the stomatal response to ABA. Résumé L'ouverture et la fermeture des stomates des plantes sont des mouvements contrôlés par des flux d'ions causant des fluctuations de la turgescence des cellules de garde. Ce procédé est en retour régulé par des signaux environnementaux et hormonaux complexes, comme la lumière et l'hormone végétale acide abscissique (ABA). Nous présentons ici des preuves génétiques montrant que les mouvements stomatiques en réponse à l'ABA sont influencés par l'expression de PHOl dans les cellules de garde d'Arabidopsis thaliana. PHOl est un exporteur de phosphate, impliqué dans l'efflux de phosphate des cellules corticales racinaires vers les vaisseaux de xylème. En con¬séquence, le mutant phol est caractérisé par de faibles niveaux de phosphate dans les parties aériennes. Dans les feuilles, PHOl est exprimé préférentiellement dans les cellules de garde, comparé au mésophylle, et est rapidement induit par le traitement à l'ABA. Le mutant phol n'est pas affecté dans la perception de l'ABA, dans la pro¬duction de ROS en réponse à l'ABA, et dans la réponse des stomates aux traitements de lumière, à l'auxine, à la fusiccocine, et la forte concentration extracellulaire de cal¬cium. En revanche, les mouvements de stomates en réponse aux traitements à l'ABA sont fortement affectés, dans l'induction de la fermeture des stomates comme dans l'inhibition de leur ouverture. De plus, les mouvements de stomates en réponse au péroxyde d'hydrogène et à la diminution du CO2 sont aussi compromis. La création de micro-greffes composées d'une partie aérienne phol greffés sur un système racinaire sauvage génère des plantes avec une croissance et une teneur en phosphate normale, mais ne permet pas de restaurer la réponse des stomates à l'ABA, ce qui démontre que le défaut de réponse à l'ABA n'est pas une simple conséquence pléiotropique de la carence en phosphate. La répression par RNAi de l'expression de PHOl dans les stomates de plantes sauvages provoque une réduction de la réponse des stomates à l'ABA, mais n'affecte pas la réponse de gènes marqueurs à l'ABA, ce qui suggère que PHOl n'agit pas au niveau transcriptionnel. Parallèlement, l'expression de PHOl dans les cellules de gardes de mutants phol complémente le phénotype stomatique mutant et rétablit la réponse à l'ABA, bien que la totale complémentation nécessite l'apport normal de phosphate aux parties aériennes. Ensemble, ces résultats révè¬lent l'influence importante de PHOl et du phosphate dans la réponse des stomates à l'ABA.

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Modern dietary habits are characterized by high-sodium and low-potassium intakes, each of which was correlated with a higher risk for hypertension. In this study, we examined whether long-term variations in the intake of sodium and potassium induce lasting changes in the plasma concentration of circulating steroids by developing a mathematical model of steroidogenesis in mice. One finding of this model was that mice increase their plasma progesterone levels specifically in response to potassium depletion. This prediction was confirmed by measurements in both male mice and men. Further investigation showed that progesterone regulates renal potassium handling both in males and females under potassium restriction, independent of its role in reproduction. The increase in progesterone production by male mice was time dependent and correlated with decreased urinary potassium content. The progesterone-dependent ability to efficiently retain potassium was because of an RU486 (a progesterone receptor antagonist)-sensitive stimulation of the colonic hydrogen, potassium-ATPase (known as the non-gastric or hydrogen, potassium-ATPase type 2) in the kidney. Thus, in males, a specific progesterone concentration profile induced by chronic potassium restriction regulates potassium balance.

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Over thirty years ago, Leamer (1983) - among many others - expressed doubts about the quality and usefulness of empirical analyses for the economic profession by stating that "hardly anyone takes data analyses seriously. Or perhaps more accurately, hardly anyone takes anyone else's data analyses seriously" (p.37). Improvements in data quality, more robust estimation methods and the evolution of better research designs seem to make that assertion no longer justifiable (see Angrist and Pischke (2010) for a recent response to Leamer's essay). The economic profes- sion and policy makers alike often rely on empirical evidence as a means to investigate policy relevant questions. The approach of using scientifically rigorous and systematic evidence to identify policies and programs that are capable of improving policy-relevant outcomes is known under the increasingly popular notion of evidence-based policy. Evidence-based economic policy often relies on randomized or quasi-natural experiments in order to identify causal effects of policies. These can require relatively strong assumptions or raise concerns of external validity. In the context of this thesis, potential concerns are for example endogeneity of policy reforms with respect to the business cycle in the first chapter, the trade-off between precision and bias in the regression-discontinuity setting in chapter 2 or non-representativeness of the sample due to self-selection in chapter 3. While the identification strategies are very useful to gain insights into the causal effects of specific policy questions, transforming the evidence into concrete policy conclusions can be challenging. Policy develop- ment should therefore rely on the systematic evidence of a whole body of research on a specific policy question rather than on a single analysis. In this sense, this thesis cannot and should not be viewed as a comprehensive analysis of specific policy issues but rather as a first step towards a better understanding of certain aspects of a policy question. The thesis applies new and innovative identification strategies to policy-relevant and topical questions in the fields of labor economics and behavioral environmental economics. Each chapter relies on a different identification strategy. In the first chapter, we employ a difference- in-differences approach to exploit the quasi-experimental change in the entitlement of the max- imum unemployment benefit duration to identify the medium-run effects of reduced benefit durations on post-unemployment outcomes. Shortening benefit duration carries a double- dividend: It generates fiscal benefits without deteriorating the quality of job-matches. On the contrary, shortened benefit durations improve medium-run earnings and employment possibly through containing the negative effects of skill depreciation or stigmatization. While the first chapter provides only indirect evidence on the underlying behavioral channels, in the second chapter I develop a novel approach that allows to learn about the relative impor- tance of the two key margins of job search - reservation wage choice and search effort. In the framework of a standard non-stationary job search model, I show how the exit rate from un- employment can be decomposed in a way that is informative on reservation wage movements over the unemployment spell. The empirical analysis relies on a sharp discontinuity in unem- ployment benefit entitlement, which can be exploited in a regression-discontinuity approach to identify the effects of extended benefit durations on unemployment and survivor functions. I find evidence that calls for an important role of reservation wage choices for job search be- havior. This can have direct implications for the optimal design of unemployment insurance policies. The third chapter - while thematically detached from the other chapters - addresses one of the major policy challenges of the 21st century: climate change and resource consumption. Many governments have recently put energy efficiency on top of their agendas. While pricing instru- ments aimed at regulating the energy demand have often been found to be short-lived and difficult to enforce politically, the focus of energy conservation programs has shifted towards behavioral approaches - such as provision of information or social norm feedback. The third chapter describes a randomized controlled field experiment in which we discuss the effective- ness of different types of feedback on residential electricity consumption. We find that detailed and real-time feedback caused persistent electricity reductions on the order of 3 to 5 % of daily electricity consumption. Also social norm information can generate substantial electricity sav- ings when designed appropriately. The findings suggest that behavioral approaches constitute effective and relatively cheap way of improving residential energy-efficiency.

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Successful expansion of haematopoietic cells in ex vivo cultures will have important applications in transplantation, gene therapy, immunotherapy and potentially also in the production of non-haematopoietic cell types. Haematopoietic stem cells (HSC), with their capacity to both self-renew and differentiate into all blood lineages, represent the ideal target for expansion protocols. However, human HSC are rare, poorly characterized phenotypically and genotypically, and difficult to test functionally. Defining optimal culture parameters for ex vivo expansion has been a major challenge. We devised a simple and reproducible stroma-free liquid culture system enabling long-term expansion of putative haematopoietic progenitors contained within frozen human fetal liver (FL) crude cell suspensions. Starting from a small number of total nucleated cells, a massive haematopoietic cell expansion, reaching > 1013-fold the input cell number after approximately 300 d of culture, was consistently achieved. Cells with a primitive phenotype were present throughout the culture and also underwent a continuous expansion. Moreover, the capacity for multilineage lymphomyeloid differentiation, as well as the recloning capacity of primitive myeloid progenitors, was maintained in culture. With its better proliferative potential as compared with adult sources, FL represents a promising alternative source of HSC and the culture system described here should be useful for clinical applications.

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Fatty acids are the basis of so-called stearates which are frequently used as lubricants in the production of ecstasy tablets. Being a product added at the initial tablet production step its composition does not change once the compression is performed. The analysis of fatty acids can therefore provide useful information for a drug intelligence purpose. In this context an appropriate analytical method was developed to improve results already obtained by routine analyses. Considering the small quantity of such fatty acids in ecstasy tablets (not, vert, similar3%) the research focussed on their extraction and concentration. Two different procedures were tested: (1) liquid/liquid extraction using dichloromethane followed by derivatisation and (2) in situ transesterification using bortrifluoride. Analyses were performed by GC-MS. The two procedures were optimized and applied to eight ecstasy seizures, in order to choose one of the procedures for its application to a large ecstasy sample set. They were compared by considering the number of peaks detected and sample amount needed, reproducibility and other technical aspects.

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Plants produce a range of biopolymers for purposes such as maintenance of structural integrity, carbon storage, and defense against pathogens and desiccation. Several of these natural polymers are used by humans as food and materials, and increasingly as an energy carrier. In this review, we focus on plant biopolymers that are used as materials in bulk applications, such as plastics and elastomers, in the context of depleting resources and climate change, and consider technical and scientific bottlenecks in the production of novel or improved materials in transgenic or alternative crop plants. The biopolymers discussed are natural rubber and several polymers that are not naturally produced in plants, such as polyhydroxyalkanoates, fibrous proteins and poly-amino acids. In addition, monomers or precursors for the chemical synthesis of biopolymers, such as 4-hydroxybenzoate, itaconic acid, fructose and sorbitol, are discussed briefly

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Résumé Ce travail vise à clarifier les résultats contradictoires de la littérature concernant les besoins des patients d'être informés et de participer à la prise de décision. La littérature insiste sur le contenu de l'information comme base de la prise de décision, bien qu'il existe des preuves que d'autres contenus sont importants pour les patients. La thèse essaie en outre d'identifier des possibilités de mieux répondre aux préférences d'information et de participation des patients. Les travaux ont porté en particulier sur les soins palliatifs. Une analyse de la littérature donne un aperçu sur les soins palliatifs, sur l'information des patients et sur leur participation à la prise de décisions thérapeutiques. Cette analyse résume les résultats d'études précédentes et propose un: modèle théorique d'information, de prise de décision et de relation entre ces deux domaines. Dans le cadre de ce travail, deux études empiriques ont utilisé des questionnaires écrits adressés à des personnes privées et à des professionnels de la santé, couvrant la Suisse et le Royaume Uni, pour identifier d'éventuelles différences entre ces deux pays. Les enquêtes ont été focalisées sur des patients souffrant de cancer du poumon. Les instruments utilisés pour ces études proviennent de la littérature afin de les rendre comparables. Le taux de réponse aux questionnaires était de 30-40%. La majorité des participants aux enquêtes estime que les patients devraient: - collaborer à la prise de décision quant à leur traitement - recevoir autant d'information que possible, positive aussi bien que négative - recevoir toutes les informations mentionnées dans le questionnaire (concernant la maladie, le diagnostic et les traitements), tenant compte de la diversité des priorités des patients - être soutenus par des professionnels de la santé, leur famille, leurs amis et/ou les personnes souffrant de la même maladie En plus, les participants aux enquêtes ont identifié divers contenus de l'information aux patients souffrant d'une maladie grave. Ces contenus comprennent entre autres: - L'aide à la prise de décision concernant le traitement - la possibilité de maintenir le contrôle de la situation - la construction d'une relation entre le patient et le soignant - l'encouragement à faire des projets d'avenir - l'influence de l'état émotionnel - l'aide à la compréhension de la maladie et de son impact - les sources potentielles d'états confusionnels et d'états anxieux La plupart des contenus proposés sont positifs. Les résultats suggèrent la coexistence possible de différents contenus à un moment donné ainsi que leur changement au cours du temps. Un modèle est ensuite développé et commenté pour présenter le diagnostic d'une maladie grave. Ce modèle est basé sur la littérature et intègre les résultats des études empiriques réalisées dans le cadre de ce travail. Ce travail analyse également les sources préférées d'information et de soutien, facteurs qui peuvent influencer ou faire obstacle aux préférences d'information et de participation. Les deux groupes de participants considèrent les médecins spécialistes comme la meilleure source d'information. En ce qui concerne le soutien, les points de vue divergent entre les personnes privées et les professionnels de la santé: généralement, les rôles de soutien semblent peu définis parmi les professionnels. Les barrières à l'information adéquate du patient apparaissent fréquemment liées aux caractéristiques des professionnels et aux problèmes d'organisation. Des progrès dans ce domaine contribueraient à améliorer les soins fournis aux patients. Finalement, les limites des études empiriques sont discutées. Celles-ci comprennent, entre autres, la représentativité restreinte des participants et les objections de certains groupes de participants à quelques détails des questionnaires. Summary The present thesis follows a call from the current body of literature to better understand patient needs for information and for participation in decision-making, as previous research findings had been contradictory. Information so far seems to have been considered essentially as a means to making treatment decisions, despite certain evidence that it may have a number of other values to patients. Furthermore, the thesis aims to identify ways to optimise meeting patient preferences for information and participation in treatment decisions. The current field of interest is palliative care. An extensive literature review depicts the background of current concepts of palliative care, patient information and patient involvement into treatment decisions. It also draws together results from previous studies and develops a theoretical model of information, decision-making, and the relationship between them. This is followed by two empirical studies collecting data from members of the general public and health care professionals by means of postal questionnaires. The professional study covers both Switzerland and the United Kingdom in order to identify possible differences between countries. Both studies focus on newly diagnosed lung cancer patients. The instruments used were taken from the literature to make them comparable. The response rate in both surveys was 30-40%, as expected -sufficient to allow stastical tests to be performed. A third study, addressed to lung cancer patients themselves, turned out to require too much time within the frame available. A majority of both study populations thought that patients should: - have a collaborative role in treatment-related decision-making -receive as much information as possible, good or bad - receive all types of information mentioned in the questionnaire (about illness, tests, and treatment), although priorities varied across the study populations - be supported by health professionals, family members, friends and/or others with the same illness Furthermore they identified various 'meanings' information may have to patients with a serious illness. These included: - being an aid in treatment-related decision-making - allowing control to be maintained over the situation - helping the patient-professional relationship to be constructed - allowing plans to be made - being positive for the patient's emotional state - helping the illness and its impact to be understood - being a source of anxiety - being a potential source of confusion to the patient Meanings were mostly positive. It was suggested that different meanings could co-exist at a given time and that they might change over time. A model of coping with the disclosure of a serious diagnosis is then developped. This model is based on existing models of coping with threatening events, as takeñ from the literature [ref. 77, 78], and integrates findings from the empirical studies. The thesis then analyses the remaining aspects apparent from the two surveys. These range from the identification of preferred information and support providers to factors influencing or impeding information and participation preferences. Specialist doctors were identified by both study populations as the best information providers whilst with regard to support provision views differed between the general public and health professionals. A need for better definition of supportive roles among health care workers seemed apparent. Barriers to information provision often seem related to health professional characteristics or organisational difficulties, and improvements in the latter field could well help optimising patient care. Finally, limitations of the studies are discussed, including questions of representativness of certain results and difficulties with or objections against questionnaire details by some groups of respondents.

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Smad (Sma and Mad-related protein) 2/3 are downstream signaling molecules for TGF-β and myostatin (Mstn). Recently, Mstn was shown to induce reactive oxygen species (ROS) in skeletal muscle via canonical Smad3, nuclear factor-κB, and TNF-α pathway. However, mice lacking Smad3 display skeletal muscle atrophy due to increased Mstn levels. Hence, our aims were first to investigate whether Mstn induced muscle atrophy in Smad3(-/-) mice by increasing ROS and second to delineate Smad3-independent signaling mechanism for Mstn-induced ROS. Herein we show that Smad3(-/-) mice have increased ROS levels in skeletal muscle, and inactivation of Mstn in these mice partially ablates the oxidative stress. Furthermore, ROS induction by Mstn in Smad3(-/-) muscle was not via nuclear factor-κB (p65) signaling but due to activated p38, ERK MAPK signaling and enhanced IL-6 levels. Consequently, TNF-α, nicotinamide adenine dinucleotide phosphate oxidase, and xanthine oxidase levels were up-regulated, which led to an increase in ROS production in Smad3(-/-) skeletal muscle. The exaggerated ROS in the Smad3(-/-) muscle potentiated binding of C/EBP homology protein transcription factor to MuRF1 promoter, resulting in enhanced MuRF1 levels leading to muscle atrophy.