909 resultados para change factors
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BACKGROUND: Intraocular gas bubbles expand as patients move up to higher altitude. This may cause an acute intraocular pressure (IOP) rise with associated vascular obstructions and visual loss. MATERIALS AND METHODS: Two pseudophakic patients underwent a pars plana vitrectomy and 23% SF6 gas tamponade for a pseudophakic retinal detachment. During the immediate post-operative phase, the patients travelled daily up to their domicile, which was situated approximately 600 m higher than the level where they had been operated on. These travels were always without any pain or visual loss. However 1 week after surgery both patients developed severe ocular pain, and one patient had complete temporary loss of vision after ascending to altitude levels, which had previously presented no problem. Both episodes occurred in parallel with a change in barometric pressure. RESULTS: Treatment with acetazolamide reduced the increased IOP to normal levels, and visual acuity recovered. CONCLUSIONS: Although the post-operative size of an intraocular gas bubble decreases progressively over time, problems with bubble expansion may still occur even at a late stage if meteorological factors, that may increase the bubble size, change.
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Summary: Global warming has led to an average earth surface temperature increase of about 0.7 °C in the 20th century, according to the 2007 IPCC report. In Switzerland, the temperature increase in the same period was even higher: 1.3 °C in the Northern Alps anal 1.7 °C in the Southern Alps. The impacts of this warming on ecosystems aspecially on climatically sensitive systems like the treeline ecotone -are already visible today. Alpine treeline species show increased growth rates, more establishment of young trees in forest gaps is observed in many locations and treelines are migrating upwards. With the forecasted warming, this globally visible phenomenon is expected to continue. This PhD thesis aimed to develop a set of methods and models to investigate current and future climatic treeline positions and treeline shifts in the Swiss Alps in a spatial context. The focus was therefore on: 1) the quantification of current treeline dynamics and its potential causes, 2) the evaluation and improvement of temperaturebased treeline indicators and 3) the spatial analysis and projection of past, current and future climatic treeline positions and their respective elevational shifts. The methods used involved a combination of field temperature measurements, statistical modeling and spatial modeling in a geographical information system. To determine treeline shifts and assign the respective drivers, neighborhood relationships between forest patches were analyzed using moving window algorithms. Time series regression modeling was used in the development of an air-to-soil temperature transfer model to calculate thermal treeline indicators. The indicators were then applied spatially to delineate the climatic treeline, based on interpolated temperature data. Observation of recent forest dynamics in the Swiss treeline ecotone showed that changes were mainly due to forest in-growth, but also partly to upward attitudinal shifts. The recent reduction in agricultural land-use was found to be the dominant driver of these changes. Climate-driven changes were identified only at the uppermost limits of the treeline ecotone. Seasonal mean temperature indicators were found to be the best for predicting climatic treelines. Applying dynamic seasonal delimitations and the air-to-soil temperature transfer model improved the indicators' applicability for spatial modeling. Reproducing the climatic treelines of the past 45 years revealed regionally different attitudinal shifts, the largest being located near the highest mountain mass. Modeling climatic treelines based on two IPCC climate warming scenarios predicted major shifts in treeline altitude. However, the currently-observed treeline is not expected to reach this limit easily, due to lagged reaction, possible climate feedback effects and other limiting factors. Résumé: Selon le rapport 2007 de l'IPCC, le réchauffement global a induit une augmentation de la température terrestre de 0.7 °C en moyenne au cours du 20e siècle. En Suisse, l'augmentation durant la même période a été plus importante: 1.3 °C dans les Alpes du nord et 1.7 °C dans les Alpes du sud. Les impacts de ce réchauffement sur les écosystèmes - en particuliers les systèmes sensibles comme l'écotone de la limite des arbres - sont déjà visibles aujourd'hui. Les espèces de la limite alpine des forêts ont des taux de croissance plus forts, on observe en de nombreux endroits un accroissement du nombre de jeunes arbres s'établissant dans les trouées et la limite des arbres migre vers le haut. Compte tenu du réchauffement prévu, on s'attend à ce que ce phénomène, visible globalement, persiste. Cette thèse de doctorat visait à développer un jeu de méthodes et de modèles pour étudier dans un contexte spatial la position présente et future de la limite climatique des arbres, ainsi que ses déplacements, au sein des Alpes suisses. L'étude s'est donc focalisée sur: 1) la quantification de la dynamique actuelle de la limite des arbres et ses causes potentielles, 2) l'évaluation et l'amélioration des indicateurs, basés sur la température, pour la limite des arbres et 3) l'analyse spatiale et la projection de la position climatique passée, présente et future de la limite des arbres et des déplacements altitudinaux de cette position. Les méthodes utilisées sont une combinaison de mesures de température sur le terrain, de modélisation statistique et de la modélisation spatiale à l'aide d'un système d'information géographique. Les relations de voisinage entre parcelles de forêt ont été analysées à l'aide d'algorithmes utilisant des fenêtres mobiles, afin de mesurer les déplacements de la limite des arbres et déterminer leurs causes. Un modèle de transfert de température air-sol, basé sur les modèles de régression sur séries temporelles, a été développé pour calculer des indicateurs thermiques de la limite des arbres. Les indicateurs ont ensuite été appliqués spatialement pour délimiter la limite climatique des arbres, sur la base de données de températures interpolées. L'observation de la dynamique forestière récente dans l'écotone de la limite des arbres en Suisse a montré que les changements étaient principalement dus à la fermeture des trouées, mais aussi en partie à des déplacements vers des altitudes plus élevées. Il a été montré que la récente déprise agricole était la cause principale de ces changements. Des changements dus au climat n'ont été identifiés qu'aux limites supérieures de l'écotone de la limite des arbres. Les indicateurs de température moyenne saisonnière se sont avérés le mieux convenir pour prédire la limite climatique des arbres. L'application de limites dynamiques saisonnières et du modèle de transfert de température air-sol a amélioré l'applicabilité des indicateurs pour la modélisation spatiale. La reproduction des limites climatiques des arbres durant ces 45 dernières années a mis en évidence des changements d'altitude différents selon les régions, les plus importants étant situés près du plus haut massif montagneux. La modélisation des limites climatiques des arbres d'après deux scénarios de réchauffement climatique de l'IPCC a prédit des changements majeurs de l'altitude de la limite des arbres. Toutefois, l'on ne s'attend pas à ce que la limite des arbres actuellement observée atteigne cette limite facilement, en raison du délai de réaction, d'effets rétroactifs du climat et d'autres facteurs limitants.
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Altitudinal tree lines are mainly constrained by temperature, but can also be influenced by factors such as human activity, particularly in the European Alps, where centuries of agricultural use have affected the tree-line. Over the last decades this trend has been reversed due to changing agricultural practices and land-abandonment. We aimed to combine a statistical land-abandonment model with a forest dynamics model, to take into account the combined effects of climate and human land-use on the Alpine tree-line in Switzerland. Land-abandonment probability was expressed by a logistic regression function of degree-day sum, distance from forest edge, soil stoniness, slope, proportion of employees in the secondary and tertiary sectors, proportion of commuters and proportion of full-time farms. This was implemented in the TreeMig spatio-temporal forest model. Distance from forest edge and degree-day sum vary through feed-back from the dynamics part of TreeMig and climate change scenarios, while the other variables remain constant for each grid cell over time. The new model, TreeMig-LAb, was tested on theoretical landscapes, where the variables in the land-abandonment model were varied one by one. This confirmed the strong influence of distance from forest and slope on the abandonment probability. Degree-day sum has a more complex role, with opposite influences on land-abandonment and forest growth. TreeMig-LAb was also applied to a case study area in the Upper Engadine (Swiss Alps), along with a model where abandonment probability was a constant. Two scenarios were used: natural succession only (100% probability) and a probability of abandonment based on past transition proportions in that area (2.1% per decade). The former showed new forest growing in all but the highest-altitude locations. The latter was more realistic as to numbers of newly forested cells, but their location was random and the resulting landscape heterogeneous. Using the logistic regression model gave results consistent with observed patterns of land-abandonment: existing forests expanded and gaps closed, leading to an increasingly homogeneous landscape.
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BACKGROUND: Prevalence of unhealthy alcohol use among medical inpatients is high. OBJECTIVE: To characterize the course and outcomes of unhealthy alcohol use, and factors associated with these outcomes. DESIGN: Prospective cohort study. PARTICIPANTS: A total of 287 medical inpatients with unhealthy alcohol use. MAIN MEASURES: At baseline and 12 months later, consumption and alcohol-related consequences were assessed. The outcome of interest was a favorable drinking outcome at 12 months (abstinence or drinking "moderate" amounts without consequences). The independent variables evaluated included demographics, physical/sexual abuse, drug use, depressive symptoms, alcohol dependence, commitment to change (Taking Action), spending time with heavy-drinking friends and receipt of alcohol treatment (after hospitalization). Adjusted regression models were used to evaluate factors associated with a favorable outcome. KEY RESULTS: Thirty-three percent had a favorable drinking outcome 1 year later. Not spending time with heavy-drinking friends [adjusted odds ratio (AOR) 2.14, 95% CI: 1.14-4.00] and receipt of alcohol treatment [AOR (95% CI): 2.16(1.20-3.87)] were associated with a favorable outcome. Compared to the first quartile (lowest level) of Taking Action, subjects in the second, third and highest quartiles had higher odds of a favorable outcome [AOR (95% CI): 3.65 (1.47, 9.02), 3.39 (1.38, 8.31) and 6.76 (2.74, 16.67)]. CONCLUSIONS: Although most medical inpatients with unhealthy alcohol use continue drinking at-risk amounts and/or have alcohol-related consequences, one third are abstinent or drink "moderate" amounts without consequences 1 year later. Not spending time with heavy-drinking friends, receipt of alcohol treatment and commitment to change are associated with this favorable outcome. This can inform efforts to address unhealthy alcohol use among patients who often do not seek specialty treatment.
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The paper analyses the positional congruence between pre-election statements in the Swiss voting assistance application "smartvote" and post-election behaviour in the Swiss lower house between 2003 and 2009. For this purpose, we selected 34 smartvote questions which subsequently came up in parliament. Unlike previous studies which assessed the program-to-policy linkage of governments or party groups the paper examines the question at the level of individual MPs which seems appropriate for political systems which follow the idea of power dispersion. While the average rate of political congruence is at some 85 percent, a multivariate analysis detects the underlying factors which push or curb a candidate's propensity to change his or her mind once elections are over. The results show that positional changes are more likely if (1) MPs are freshmen, (2) individual voting behaviour is invisible to the public, (3) the vote is not about a party's core issue, (4) the MP belongs to a party which is located in the political centre, and (5) if the pre-election statement is in disagreement with the majority position of the legislative party group. The last-mentioned factor is paramount: the farer away a candidate's pre-election profile from his or her party is located, the weaker turns out to be the electoral link of promissory representation.
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BACKGROUND: Screening tests for subclinical cardiovascular disease, such as markers of atherosclerosis, are increasingly used in clinical prevention to identify individuals at high cardiovascular risk. Being aware of these test results might also enhance patient motivation to change unhealthy behaviors but the effectiveness of such a screening strategy has been poorly studied. METHODS: The CAROtid plaque Screening trial on Smoking cessation (CAROSS) is a randomized controlled trial in 530 regular smokers aged 40-70 years to test the hypothesis that carotid plaque screening will influence smokers' behavior with an increased rate of smoking cessation (primary outcome) and an improved control of other cardiovascular risk factors (secondary outcomes) after 1-year follow-up. All smokers will receive a brief advice for smoking cessation,and will subsequently be randomly assigned to either the intervention group (with plaques screening) or the control group (without plaque screening). Carotid ultrasound will be conducted with a standard protocol. Smokers with at least one carotid plaque will receive pictures of their own plaques with a structured explanation on the general significance of plaques. To ensure equal contact conditions, smokers not undergoing ultrasound and those without plaque will receive a relevant explanation on the risks associated with tobacco smoking. Study outcomes will be compared between smokers randomized to plaque screening and smokers not submitted to plaque screening. SUMMARY: This will be the first trial to assess the impact of carotid plaque screening on 1-year smoking cessation rates and levels of control of other cardiovascular risk factors.
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Public Policy and Ageing in Northern Ireland: Identifying Levers for Change Judith Cross, Policy Officer with the Centre for Ageing Research Development in Ireland (CARDI)��������Introduction Identifying a broad range of key public policy initiatives as they relate to age can facilitate discussion and create new knowledge within and across government to maximise the opportunities afforded by an ageing population. This article looks at how examining the current public policy frameworks in Northern Ireland can present opportunities for those working in this field for the benefit of older people. Good policy formulation needs to be evidence-based, flexible, innovative and look beyond institutional boundaries. Bringing together architects and occupational therapists, for example, has the potential to create better and more effective ways relevant to health, housing, social services and government departments. Traditional assumptions of social policy towards older people have tended to be medically focused with an emphasis on care and dependency. This in turn has consequences for the design and delivery of services for older people. It is important that these assumptions are challenged as changes in thinking and attitudes can lead to a redefinition of ageing, resulting in policies and practices that benefit older people now and in the future. Older people, their voices and experiences, need to be central to these developments. The Centre for Ageing Research and Development in Ireland The Centre for Ageing Research and Development in Ireland (CARDI) (1) is a not for profit organisation developed by leaders from the ageing field across Ireland (North and South) including age sector focused researchers and academics, statutory and voluntary, and is co-chaired by Professor Robert Stout and Professor Davis Coakley. CARDI has been established to provide a mechanism for greater collaboration among age researchers, for wider dissemination of ageing research information and to advance a research agenda relevant to the needs of older people in Ireland, North and South. Operating at a strategic level and in an advisory capacity, CARDI�۪s work focuses on promoting research co-operation across sectors and disciplines and concentrates on influencing the strategic direction of research into older people and ageing in Ireland. It has been strategically positioned around the following four areas: Identifying and establishing ageing research priorities relevant to policy and practice in Ireland, North and South;Promoting greater collaboration and co-operation on ageing research in order to build an ageing research community in Ireland, North and South;Stimulating research in priority areas that can inform policy and practice relating to ageing and older people in Ireland, North and South;Communicating strategic research issues on ageing to raise the profile of ageing research in Ireland, North and South, and its role in informing policy and practice. Context of Ageing in Ireland Ireland �۪s population is ageing. One million people aged 60 and over now live on the island of Ireland. By 2031, it is expected that Northern Ireland�۪s percentage of older people will increase to 28% and the Republic of Ireland�۪s to 23%. The largest increase will be in the older old; the number aged 80+ is expected to triple by the same date. However while life expectancy has increased, it is not clear that life without disability and ill health has increased to the same extent. A growing number of older people may face the combined effects of a decline in physical and mental function, isolation and poverty. Policymakers, service providers and older people alike recognise the need to create a high quality of life for our ageing population. This challenge can be meet by addressing the problems relating to healthy ageing, reducing inequalities in later life and creating services that are shaped by, and appropriate for, older people. Devolution and Structures of Government in Northern Ireland The Agreement (2) reached in the Multi-Party Negotiations in Belfast 1998 established the Northern Ireland Assembly which has full legislative authority for all transferred matters. The majority of social and economic public policy such as; agriculture, arts, education, health, environment and planning is determined by the Northern Ireland Assembly at Stormont. There are 11 Government Departments covering the main areas of responsibility with 108 elected Members of the Legislative Assembly (MLA�۪s). The powers of the Northern Ireland Assembly do not cover ��� reserved�۪ matters or ��� excepted�۪ matters . These are the responsibility of Westminster and include issues such as, tax, social security, policing, justice, defence, immigration and foreign affairs. Northern Ireland has 18 elected Members of Parliament (MP�۪s) to the House of Commons. Public Policy Context in Northern Ireland The economic, social and political consequence of an ageing population is a challenge for policy makers across government. Considering the complex and diverse causal factors that contribute to ageing in Northern Ireland, there are a number of areas of government policy at regional, national and international levels that are likely to impact in this area. International The Madrid International Plan of Action on Ageing (3) and the Research Agenda on Ageing for the 21st Century (4) provide important mechanisms for furthering research into ageing. The United Kingdom has signed up to these. The Madrid International Plan of Action on Ageing commits member states to a systematic review of the Plan of Action through Regional Implementation Strategies. The United Kingdom�۪s Regional Implementation Strategy covers Northern Ireland. National At National level, pension and social security are high on the agenda. The Pensions Act (5) became law in 2007 and links pensions increases with earnings as opposed to prices from 2012. Additional credits for people raising children and caring for older people to boost their pensions were introduced. Some protections are included for those who lost occupational pensions as a result of underfunded schemes being wound up before April 2005. In relation to State Pensions and benefits, this Act will bring changes to state pensions in future. The Act now places the Pension Credit element which is up-rated in line with or above earnings, on a permanent, statutory footing. Regional At regional level there are a number of age related public policy initiatives that have the potential to impact positively on the lives of older people in Northern Ireland. Some are specific to ageing such as the Ageing in an Inclusive Society (6) and others by their nature are cross-cutting such as Lifetime Opportunities: Governments Anti-Poverty Strategy for Northern Ireland (7). The main public policy framework in Northern Ireland is the Programme for Government: Building a Better Future, 2008-2011(PfG) (8) . The PfG, is the overarching high level policy framework for Northern Ireland and provides useful principles for ageing research and public policy in Northern Ireland. The PfG vision is to build a peaceful, fair and prosperous society in Northern Ireland, with respect for the rule of law. A number of Public Service Agreements (PSA) aligned to the PfG confirm key actions that will be taken to support the priorities that the Government aim to achieve over the next three years. For example objective 2 of PSA 7: Making Peoples�۪ Lives Better: Drive a programme across Government to reduce poverty and address inequality and disadvantage, refers to taking forward strategic action to promote social inclusion for older people; and to deliver a strong independent voice for older people. The Office of the First Minister and deputy First Minister (OFMDFM) have recently appointed an Interim Older People�۪s Advocate, Dame Joan Harbison to provide a focus for older peoples issues across Government. Ageing in an Inclusive Society is the cross-departmental strategy for older people in Northern Ireland and was launched in March 2005. It sets out the approach to be taken across Government to promote and support the inclusion of older people. The vision coupled with six strategic objectives form the basis of the action plans accompanying the strategy. The vision is: ���To ensure that age related policies and practices create an enabling environment, which offers everyone the opportunity to make informed choices so that they may pursue healthy, active and positive ageing.� (Ageing in an Inclusive Society, Office of the First Minister and Deputy First Minister, 2005) Action planning and maintaining momentum across government in relation to this strategy has proved to be slower than anticipated. It is proposed to refresh this Strategy in line with Opportunity Age ��� meeting the challenges of ageing in the 21st Century (9). There are a number of policy levers elsewhere which can also be used to promote the positive aspects of an ageing society. The Investing for Health (10) and A Healthier Future:A 20 Year Vision for Health and Well-being in Northern Ireland (11), seek to ensure that the overall vision for health and wellbeing is achievable and provides a useful framework for ageing policy and research in the health area. These health initiatives have the potential to positively impact on the quality of life of older people and provide a useful framework for improving current policy and practice. In addition to public policy initiatives, the anti-discrimination frameworks in terms of employment in Northern Ireland cover age as well as a range of other grounds. Goods facilitates and services are currently excluded from the Employment Equality (age) Regulations (NI) 2006 (12). Supplementing the anti-discrimination measures, Section 75 of the Northern Ireland Act 1998 (13), unique to Northern Ireland, places a statutory obligation on public authorities in fulfilling their functions to promote equality of opportunity across nine grounds, one of which is age(14). This positive duty has the potential to make a real difference to the lives of older people in Northern Ireland. Those affected by policy decisions must be consulted and their interests taken into account. This provides an opportunity for older people and their representatives to participate in public policy-making, right from the start of the process. Policy and Research Interface ���Ageing research is vital as decisions in relation to policy and practice and resource allocation will be made on the best available information�. (CARDI�۪s Strategic Plan 2008-2011) As outlined earlier, CARDI has been established to bridge the gap to ensure that research reaches those involved in making policy decisions. CARDI is stimulating the ageing research agenda in Ireland through a specific research fund that has a policy and practice focus. My work is presently focusing on helping to build a greater awareness of the key policy levers and providing opportunities for those within research and policy to develop closer links. The development of this shared understanding by establishing these links between researchers and policy makers is seen as the best predictor for research utilization. It is important to acknowledge and recognise that researchers and policy makers operate in different institutional, political and cultural contexts. Research however needs to ���resonate�۪ with the contextual factors in which policy makers operate. Conclusions Those working within the public policy field recognise all too often that the development of government policies and initiatives in respect of age does not guarantee that they will result in changes in actual provision of services, despite Government recommendations and commitments. The identification of public policy initiatives as they relate to age has the potential to highlight persistent and entrenched difficulties that social policy has previously failed to address. Furthermore, the identification of these difficulties can maximise the opportunities for progressing these across government. A focus on developing effective and meaningful targets to ensure measurable outcomes in public policy for older people can assist in this. Access to sound, credible and up-to-date evidence will be vital in this respect. As well as a commitment to working across departmental boundaries to effect change. Further details: If you would like to discuss this paper or for further information about CARDI please contact: Judith Cross, Policy Officer, Centre for Ageing Research and Development in Ireland CARDI). t: +44 (0) 28 9069 0066; m: +353 (0) 867 904 171; e: judith@cardi.ie ; or visit our website at: www.cardi.ie References 1) Centre for Ageing Research and Development in Ireland (2008) Strategic Plan 2008-2011. Belfast. CARDI 2) The Agreement: Agreement Reached in the Multi-Party Negotiations. Belfast 1998 3) Madrid International Plan of Action on Ageing. http://www.un.org/ageing/ 4) UN Programme on Ageing (2007) Research Agenda on Ageing for the 21st Century: 2007 Update. New York. New York. UN Programme on Ageing and the International Association of Gerontology and Geriatrics. 5) The Pensions Act 2007 Chapter 22 6) Office of the First Minister and deputy First Minister (2005). Ageing in an Inclusive Society. Belfast. OFMDFM Central Anti-Poverty Unit. 7) Office of the First Minister and deputy First Minister (2005). Lifetime Opportunities: Government�۪s Anti-Poverty and Social Inclusion Strategy for Northern Ireland. Belfast. OFMDFM Central Anti-Poverty Unit. 8) Northern Ireland Executive (2008) Building a Better Future: Programme for Government 2008-2011. Belfast. OFMDFM Economic Policy Unit. 9) Department for Work and Pensions, (2005) Opportunity Age: Meeting the Challenges of Ageing in the 21 st Century. London. DWP. 10) Department of Health, Social Services and Public Safety (DHSS&PS) (2002) Investing for Health. Belfast. DHSS&PS. 11) Department of Health, Social Services and Public Safety (DHSS&PS) (2005) A Healthier Future:A 20 Year Vision for Health and Well-being in Northern Ireland Belfast. DHSS&PS. �� 12) The Employment Equality (Age) Regulations (Northern Ireland) 2006 SR2006 No.261 13) The Northern Ireland Act 1998, Part VII, S75 14) The nine grounds covered under S75 of the Northern Ireland Act are: gender, religion, race, sexual orientation, those with dependents, disability, political opinion, marital status and age.
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PURPOSE: The origin of the slow component is not fully understood. The mechanical hypothesis is one of the potential factors, because an increase in external mechanical work with fatigue was previously reported for a constant velocity run. The purpose of this study was to determine whether a change in mechanical work could occur during the development of the VO2 slow component under the effect of fatigue. METHODS: Twelve regional-level competitive runners performed a square-wave transition, corresponding to 95% of the speed associated with peak VO2 obtained during an incremental test. The VO2 response was fit with a classical model including two exponential functions. A specific treadmill with three-dimensional force transducers was used to measure the ground reaction force. Kinetic work (W(kin)), potential work (W(pot)), external work (W(ext)), and an index of internal work (W(int)) per unit of distance were quantified continuously. RESULTS: During the slow component of VO2, a significant increase in W (P< 0.01), no change in W, and a significant decrease in W and W index (P< 0.05, P< 0.001, respectively) were observed. CONCLUSION: The present study showed that the slow component of VO2 did not result partly from a change in mechanical work under the effect of fatigue. Nevertheless, the decrease in stride frequency (P< 0.001) and contact time (P< 0.001) suggested an alternative mechanical explanation. The slow component during running may be due to the cost of generating force or to alterations in the storage and recoil of elastic energy, and not to the external mechanical work.
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Extended-spectrum β-lactamases (ESBLs) form a heterogeneous group that share the property of hydrolytic activity against the oxyimino-β-lactams while remaining susceptible to inhibition by β-lactamase inhibitors, such as clavulanic acid. From a clinical point of view, they are important because they confer resistance to penicillins, aztreonam, and cephalosporins, and ESBL-producing organisms are typically also resistant to aminoglycosides, trimethoprim-sulfamethoxazole, and quinolones [1]. Until recently, the main problem posed by ESBLs was related to nosocomial outbreaks caused by ESBL-producing Klebsiella species. These outbreaks are usually clonal, the strains are mainly spread through cross-transmission, and the risk factors are similar to those found for other multidrug-resistant nosocomial pathogens [2]. In Europe and the United States, most ESBL-producing Klebsiella isolates harbored enzymes belonging to the TEM and SHV families [3]. Detection of colonized patients by performing surveillance cultures within affected units, isolation precautions for colonized patients, and restriction of oxyimino-β-lactam use are frequently useful for the control of these outbreaks [1]. There is no evidence that hospital-acquired ESBL-producing klebsiellae are decreasing in importance—in fact, data from the Centers for Disease Control and Prevention show that 20.6% of Klebsiella pneumoniae isolates from United States intensive care units in 2003 were probable producers of ESBL [4]. This represented a 47% increase, compared with the preceding 5 years. However, during the last few years, an impressive increase in the number of ESBL-producing Escherichia coli (and, less frequently, other Enterobacteriaceae) is being described in several parts of the world [5–8]. This emergent phenomenon shows some differences from the problem posed by Klebsiella species; many of these ESBL-producing E. coli are isolated …
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The distribution of living organisms, habitats and ecosystems is primarily driven by abiotic environmental factors that are spatially structured. Assessing the spatial structure of environmental factors, e.g., through spatial autocorrelation analyses (SAC), can thus help us understand their scale of influence on the distribution of organisms, habitats, and ecosystems. Yet SAC analyses of environmental factors are still rarely performed in biogeographic studies. Here, we describe a novel framework that combines SAC and statistical clustering to identify scales of spatial patterning of environmental factors, which can then be interpreted as the scales at which those factors influence the geographic distribution of biological and ecological features. We illustrate this new framework with datasets at different spatial or thematic resolutions. This framework is conceptually and statistically robust, providing a valuable approach to tackle a wide range of issues in ecological and environmental research and particularly when building predictors for ecological models. The new framework can significantly promote fundamental research on all spatially-structured ecological patterns. It can also foster research and application in such fields as global change ecology, conservation planning, and landscape management.
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Impact of immune microenvironment in prognosis of solid tumors has been extensively studied in the last few years. Specifically in colorectal carcinoma, increased knowledge of the immune events around these tumors and their relation with clinical outcomes have led to consider immune microenvironment as one of the most important prognostic factors in this disease. In this review we will summarize and update the current knowledge with respect to this intriguing and complex new hallmark of cancer, paying special attention to infiltration by T-infiltrating lymphocytes and their subtypes in colorectal cancer, as well as its eventual clinical translation in terms of long-term prognosis. Finally, we suggest some possible investigational approaches based on combinatorial strategies to trigger and boost immune reaction against tumor cells.
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SUMMARY: BMD and clinical risk factors predict hip and other osteoporotic fractures. The combination of clinical risk factors and BMD provide higher specificity and sensitivity than either alone. INTRODUCTION AND HYPOTHESES: To develop a risk assessment tool based on clinical risk factors (CRFs) with and without BMD. METHODS: Nine population-based studies were studied in which BMD and CRFs were documented at baseline. Poisson regression models were developed for hip fracture and other osteoporotic fractures, with and without hip BMD. Fracture risk was expressed as gradient of risk (GR, risk ratio/SD change in risk score). RESULTS: CRFs alone predicted hip fracture with a GR of 2.1/SD at the age of 50 years and decreased with age. The use of BMD alone provided a higher GR (3.7/SD), and was improved further with the combined use of CRFs and BMD (4.2/SD). For other osteoporotic fractures, the GRs were lower than for hip fracture. The GR with CRFs alone was 1.4/SD at the age of 50 years, similar to that provided by BMD (GR = 1.4/SD) and was not markedly increased by the combination (GR = 1.4/SD). The performance characteristics of clinical risk factors with and without BMD were validated in eleven independent population-based cohorts. CONCLUSIONS: The models developed provide the basis for the integrated use of validated clinical risk factors in men and women to aid in fracture risk prediction.
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BACKGROUND The effect of the macronutrient composition of the usual diet on long term weight maintenance remains controversial. METHODS 373,803 subjects aged 25-70 years were recruited in 10 European countries (1992-2000) in the PANACEA project of the EPIC cohort. Diet was assessed at baseline using country-specific validated questionnaires and weight and height were measured at baseline and self-reported at follow-up in most centers. The association between weight change after 5 years of follow-up and the iso-energetic replacement of 5% of energy from one macronutrient by 5% of energy from another macronutrient was assessed using multivariate linear mixed-models. The risk of becoming overweight or obese after 5 years was investigated using multivariate Poisson regressions stratified according to initial Body Mass Index. RESULTS A higher proportion of energy from fat at the expense of carbohydrates was not significantly associated with weight change after 5 years. However, a higher proportion of energy from protein at the expense of fat was positively associated with weight gain. A higher proportion of energy from protein at the expense of carbohydrates was also positively associated with weight gain, especially when carbohydrates were rich in fibre. The association between percentage of energy from protein and weight change was slightly stronger in overweight participants, former smokers, participants ≥60 years old, participants underreporting their energy intake and participants with a prudent dietary pattern. Compared to diets with no more than 14% of energy from protein, diets with more than 22% of energy from protein were associated with a 23-24% higher risk of becoming overweight or obese in normal weight and overweight subjects at baseline. CONCLUSION Our results show that participants consuming an amount of protein above the protein intake recommended by the American Diabetes Association may experience a higher risk of becoming overweight or obese during adult life.
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Climate warming leads to a decrease in biodiversity. Organisms can deal with the new prevailing environmental conditions by one of two main routes, namely evolving new genetic adaptations or through phenotypic plasticity to modify behaviour and physiology. Melanin-based colouration has important functions in animals including a role in camouflage and thermoregulation, protection against UV-radiation and pathogens and, furthermore, genes involved in melanogenesis can pleiotropically regulate behaviour and physiology. In this article, I review the current evidence that differently coloured individuals are differentially sensitive to climate change. Predicting which of dark or pale colour variants (or morphs) will be more penalized by climate change will depend on the adaptive function of melanism in each species as well as how the degree of colouration covaries with behaviour and physiology. For instance, because climate change leads to a rise in temperature and UV-radiation and dark colouration plays a role in UV-protection, dark individuals may be less affected from global warming, if this phenomenon implies more solar radiation particularly in habitats of pale individuals. In contrast, as desertification increases, pale colouration may expand in those regions, whereas dark colourations may expand in regions where humidity is predicted to increase. Dark colouration may be also indirectly selected by climate warming because genes involved in the production of melanin pigments confer resistance to a number of stressful factors including those associated with climate warming. Furthermore, darker melanic individuals are commonly more aggressive than paler conspecifics, and hence they may better cope with competitive interactions due to invading species that expand their range in northern latitudes and at higher altitudes. To conclude, melanin may be a major component involved in adaptation to climate warming, and hence in animal populations melanin-based colouration is likely to change as an evolutionary or plastic response to climate warming.
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BACKGROUND Few epidemiological studies have examined the association between dietary trans fatty acids and weight gain, and the evidence remains inconsistent. The main objective of the study was to investigate the prospective association between biomarker of industrial trans fatty acids and change in weight within the large study European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. METHODS Baseline plasma fatty acid concentrations were determined in a representative EPIC sample from the 23 participating EPIC centers. A total of 1,945 individuals were followed for a median of 4.9 years to monitor weight change. The association between elaidic acid level and percent change of weight was investigated using a multinomial logistic regression model, adjusted by length of follow-up, age, energy, alcohol, smoking status, physical activity, and region. RESULTS In women, doubling elaidic acid was associated with a decreased risk of weight loss (odds ratio (OR) = 0.69, 95% confidence interval (CI) = 0.55-0.88, p = 0.002) and a trend was observed with an increased risk of weight gain during the 5-year follow-up (OR = 1.23, 95% CI = 0.97-1.56, p = 0.082) (p-trend<.0001). In men, a trend was observed for doubling elaidic acid level and risk of weight loss (OR = 0.82, 95% CI = 0.66-1.01, p = 0.062) while no significant association was found with risk of weight gain during the 5-year follow-up (OR = 1.08, 95% CI = 0.88-1.33, p = 0.454). No association was found for saturated and cis-monounsaturated fatty acids. CONCLUSIONS These data suggest that a high intake of industrial trans fatty acids may decrease the risk of weight loss, particularly in women. Prevention of obesity should consider limiting the consumption of highly processed foods, the main source of industrially-produced trans fatty acids.