918 resultados para Intensive and extensive margin


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INTRODUCTION: Catheter-associated bloodstream infection (CA-BSI) is the most common nosocomial infection in neonatal intensive care units. There is evidence that care bundles to reduce CA-BSI are effective in the adult literature. The aim of this study was to reduce CA-BSI in a Brazilian neonatal intensive care unit by means of a care bundle including few strategies or procedures of prevention and control of these infections. METHODS: An intervention designed to reduce CA-BSI with five evidence-based procedures was conducted. RESULTS: A total of sixty-seven (26.7%) CA-BSIs were observed. There were 46 (32%) episodes of culture-proven sepsis in group preintervention (24.1 per 1,000 catheter days [CVC days]). Neonates in the group after implementation of the intervention had 21 (19.6%) episodes of CA-BSI (14.9 per 1,000 CVC days). The incidence of CA-BSI decreased significantly after the intervention from the group preintervention and postintervention (32% to 19.6%, 24.1 per 1,000 CVC days to 14.9 per 1,000 CVC days, p=0.04). In the multiple logistic regression analysis, the use of more than 3 antibiotics and length of stay >8 days were independent risk factors for BSI. CONCLUSIONS: A stepwise introduction of evidence-based intervention and intensive and continuous education of all healthcare workers are effective in reducing CA-BSI.

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The geomorphological materials and forms of the Maraca area of Roraima, Brazil are described, an their sgnificance for land development examined. Significant contrasts are noted in areas presently under rainforest and savanna vegetation. Lateritic gravels and extensive shetwash accumulations in savanna areas constrast with incipient or absent plinthite development, few gravels and limited evidence of colluvium under rainforest. Terrain is in general relatively highly-dissected. Slope profiles are characterised, particularly within the savanna zone, by a relatively steep lower concavity. These contrasts are sharply-demarcated by the present savanna/rainforest bondary, unexpectedly in view of the generally accepted hypothesis of repeated contraction an expansion of Amazonian rainforest throughout the Pleistocene. It is concluded that geomorphological conditions in the Maraca area are not favorable for land develoment.

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Information security is concerned with the protection of information, which can be stored, processed or transmitted within critical information systems of the organizations, against loss of confidentiality, integrity or availability. Protection measures to prevent these problems result through the implementation of controls at several dimensions: technical, administrative or physical. A vital objective for military organizations is to ensure superiority in contexts of information warfare and competitive intelligence. Therefore, the problem of information security in military organizations has been a topic of intensive work at both national and transnational levels, and extensive conceptual and standardization work is being produced. A current effort is therefore to develop automated decision support systems to assist military decision makers, at different levels in the command chain, to provide suitable control measures that can effectively deal with potential attacks and, at the same time, prevent, detect and contain vulnerabilities targeted at their information systems. The concept and processes of the Case-Based Reasoning (CBR) methodology outstandingly resembles classical military processes and doctrine, in particular the analysis of “lessons learned” and definition of “modes of action”. Therefore, the present paper addresses the modeling and design of a CBR system with two key objectives: to support an effective response in context of information security for military organizations; to allow for scenario planning and analysis for training and auditing processes.

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Land cover changes over time as a result of human activity. Nowadays deforestation may be considered one of the main environmental problems. The objective of this study was to identify and characterize changes to forest cover in Venezuela between 2005-2010. Two maps of deforestation hot spots were generated on the basis of MODIS data, one using digital techniques and the other by means of direct visual interpretation by experts. These maps were validated against Landsat ETM+ images. The accuracy of the map obtained digitally was estimated by means of a confusion matrix. The overall accuracy of the maps obtained digitally was 92.5%. Expert opinions regarding the hot spots permitted the causes of deforestation to be identified. The main processes of deforestation were concentrated to the north of the Orinoco River, where 8.63% of the country's forests are located. In this region, some places registered an average annual forest change rate of between 0.72% and 2.95%, above the forest change rate for the country as a whole (0.61%). The main causes of deforestation for the period evaluated were agricultural and livestock activities (47.9%), particularly family subsistence farming and extensive farming which were carried out in 94% of the identified areas.

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OBJECTIVES: Discuss pathophysiological aspects of cerebral calcifications (CC) and highlight its importance related to the occurrence of neuropsychiatric syndromes. METHOD: Single case report. RESULT: Man 52 years old, 20 years after going through a total thyroidectomy, starts showing behavioral disturbance (psychotic syndrome). He was diagnosed as schizophrenic (paranoid subtype) and submitted to outpatient psychiatric treatment. During a psychiatric admission to evaluate his progressive cognitive and motor deterioration, we identified a dementia syndrome and extensive cerebral calcifications, derived from iatrogenic hypoparathyroidism. CONCLUSION: The calcium and phosphorus disturbances, including hypoparathyroidism, are common causes of CC. Its symptoms can imitate psychiatric disorders and produce serious and permanent cognitive sequelae. The exclusion of organicity is mandatory in any psychiatric investigative diagnosis in order to avoid unfavorable outcomes, such as in the present case report.

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Abdominal Aortic Aneurysms (AAA) haemorhaging is a life-threatening disease. An aneurysm is a permanent swelling of an artery due to a weakness in its wall. Current surgical repair involves opening the chest or abdomen, gaining temporary vascular control of the aorta and suturing a prosthetic graft to the healthy aorta within the aneurysm itself The outcome of this surgical approach is not perfect, and the quality of life after this repair is impaired by postoperative pain, sexual dysfunction, and a lengthy hospital stay resulting in high health costs. All these negative effects are related to the large incision and extensive tissue dissection. Endovascular grafting is an alternative to the standard surgical method. This treatment is a less invasive method of treating aortic aneurysms. It involves a surgical exposure of the common femoral arteries where the stent graft can be inserted through by an over-the-wire technique. All manipulations are controlled from a remote place by the use of a catheter and this technique avoids the need to directly expose the diseased artery through a large incision or an extensive dissection. The proposed design method outlined in this project is to develop the endovascular approach. The main aim is to design an unitary bifurcated stent graft (1 e- bifurcated graft as a single component) to treat these Abdominal Aortic Aneurysms. This includes the delivery system and deployment mechanism necessary to first accurately position the stent graft across the aneurysm sac and also across the iliac bifurcation, and secondly fix the stent graft in position by using expandable metal stents. Thus, excluding the aneurysm from the circulation and therefore preventing rupture. Miniaturisation is a critical aspect of this design, as the smaller the crimped stent graft the easier to guide through the vascular system to the desired location. Biocompatibility is an important aspect. The preferred materials for this prosthesis are to use Shape Memory Alloys for the stent and a multifilament fabric for the graft. A taper design is applied for the geometry as this gives a favourable flow characteristic and reduced wave reflections. Adequate testing of the stent graft to prove its durability and the ease of the method of deployment is a prerequisite. A bench test facility has being designed and build to replicate the cardiovascular system and the disease in question aortic aneurysms at the iliac bifurcation. The testing here shows the feasibility of the proposed delivery system and the durability of the stent graft across the aneurysm sac. Finally, these endovascular treatments offer the economic advantage of short hospital stays or even treatment as an outpatient, as well as elimination of the need for postoperative intensive care The risk of developing an aneurysm increases with age, that is one of the mam reasons to look for less invasive ways of treating aneurysms. Consequently, there is enormous pressure to develop and use these devices rapidly.

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Since 1895, when X-rays were discovered, ionizing radiation became part of our life. Its use in medicine has brought significant health benefits to the population globally. The benefit of any diagnostic procedure is to reduce the uncertainty about the patient's health. However, there are potential detrimental effects of radiation exposure. Therefore, radiation protection authorities have become strict regarding the control of radiation risks.¦There are various situations where the radiation risk needs to be evaluated. International authority bodies point to the increasing number of radiologic procedures and recommend population surveys. These surveys provide valuable data to public health authorities which helps them to prioritize and focus on patient groups in the population that are most highly exposed. On the other hand, physicians need to be aware of radiation risks from diagnostic procedures in order to justify and optimize the procedure and inform the patient.¦The aim of this work was to examine the different aspects of radiation protection and investigate a new method to estimate patient radiation risks.¦The first part of this work concerned radiation risk assessment from the regulatory authority point of view. To do so, a population dose survey was performed to evaluate the annual population exposure. This survey determined the contribution of different imaging modalities to the total collective dose as well as the annual effective dose per caput. It was revealed that although interventional procedures are not so frequent, they significantly contribute to the collective dose. Among the main results of this work, it was shown that interventional cardiological procedures are dose-intensive and therefore more attention should be paid to optimize the exposure.¦The second part of the project was related to the patient and physician oriented risk assessment. In this part, interventional cardiology procedures were studied by means of Monte Carlo simulations. The organ radiation doses as well as effective doses were estimated. Cancer incidence risks for different organs were calculated for different sex and age-at-exposure using the lifetime attributable risks provided by the Biological Effects of Ionizing Radiations Report VII. Advantages and disadvantages of the latter results were examined as an alternative method to estimate radiation risks. The results show that this method is the most accurate, currently available, to estimate radiation risks. The conclusions of this work may guide future studies in the field of radiation protection in medicine.¦-¦Depuis la découverte des rayons X en 1895, ce type de rayonnement a joué un rôle important dans de nombreux domaines. Son utilisation en médecine a bénéficié à la population mondiale puisque l'avantage d'un examen diagnostique est de réduire les incertitudes sur l'état de santé du patient. Cependant, leur utilisation peut conduire à l'apparition de cancers radio-induits. Par conséquent, les autorités sanitaires sont strictes quant au contrôle du risque radiologique.¦Le risque lié aux radiations doit être estimé dans différentes situations pratiques, dont l'utilisation médicale des rayons X. Les autorités internationales de radioprotection indiquent que le nombre d'examens et de procédures radiologiques augmente et elles recommandent des enquêtes visant à déterminer les doses de radiation délivrées à la population. Ces enquêtes assurent que les groupes de patients les plus à risque soient prioritaires. D'un autre côté, les médecins ont également besoin de connaître le risque lié aux radiations afin de justifier et optimiser les procédures et informer les patients.¦Le présent travail a pour objectif d'examiner les différents aspects de la radioprotection et de proposer une manière efficace pour estimer le risque radiologique au patient.¦Premièrement, le risque a été évalué du point de vue des autorités sanitaires. Une enquête nationale a été réalisée pour déterminer la contribution des différentes modalités radiologiques et des divers types d'examens à la dose efficace collective due à l'application médicale des rayons X. Bien que les procédures interventionnelles soient rares, elles contribuent de façon significative à la dose délivrée à la population. Parmi les principaux résultats de ce travail, il a été montré que les procédures de cardiologie interventionnelle délivrent des doses élevées et devraient donc être optimisées en priorité.¦La seconde approche concerne l'évaluation du risque du point de vue du patient et du médecin. Dans cette partie, des procédures interventionnelles cardiaques ont été étudiées au moyen de simulations Monte Carlo. La dose délivrée aux organes ainsi que la dose efficace ont été estimées. Les risques de développer des cancers dans plusieurs organes ont été calculés en fonction du sexe et de l'âge en utilisant la méthode établie dans Biological Effects of Ionizing Radiations Report VII. Les avantages et inconvénients de cette nouvelle technique ont été examinés et comparés à ceux de la dose efficace. Les résultats ont montré que cette méthode est la plus précise actuellement disponible pour estimer le risque lié aux radiations. Les conclusions de ce travail pourront guider de futures études dans le domaine de la radioprotection en médicine.

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PURPOSE: Tumor-associated TIE-2-expressing monocytes (TEM) are highly proangiogenic cells critical for tumor vascularization. We previously showed that, in human breast cancer, TIE-2 and VEGFR pathways control proangiogenic activity of TEMs. Here, we examine the contribution of these pathways to immunosuppressive activity of TEMs. EXPERIMENTAL DESIGN: We investigated the changes in immunosuppressive activity of TEMs and gene expression in response to specific kinase inhibitors of TIE-2 and VEGFR. The ability of tumor TEMs to suppress tumor-specific T-cell response mediated by tumor dendritic cells (DC) was measured in vitro. Characterization of TEM and DC phenotype in addition to their interaction with T cells was done using confocal microscopic images analysis of breast carcinomas. RESULTS: TEMs from breast tumors are able to suppress tumor-specific immune responses. Importantly, proangiogenic and suppressive functions of TEMs are similarly driven by TIE-2 and VEGFR kinase activity. Furthermore, we show that tumor TEMs can function as antigen-presenting cells and elicit a weak proliferation of T cells. Blocking TIE-2 and VEGFR kinase activity induced TEMs to change their phenotype into cells with features of myeloid dendritic cells. We show that immunosuppressive activity of TEMs is associated with high CD86 surface expression and extensive engagement of T regulatory cells in breast tumors. TIE-2 and VEGFR kinase activity was also necessary to maintain high CD86 surface expression levels and to convert T cells into regulatory cells. CONCLUSIONS: These results suggest that TEMs are plastic cells that can be reverted from suppressive, proangiogenic cells into cells that are able to mediate an antitumoral immune response. Clin Cancer Res; 19(13); 3439-49. ©2013 AACR.

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Eosinophils have long been thought to be effectors of immunity to helminths but have also been implicated in the pathogenesis of asthma. Patterns of cytokine production in the host may influence the pathogenesis of these diseases by regulating the activities of eosinophils and other components of the immune response. Mice which constitutively over-express IL-5 have profound and life-long eosinophilia in a restricted number of tissues. Although eosinophils from IL-5 transgenics are functionally competent for a number of parameters considered to be important in inflammation, untreated animals are overtly normal and free of disease. In addition, the responses of these animals when exposed to aeroallergens and helminths present a number of apparent paradoxes. Eosinophil accumulation in tissues adjacent to major airways is rapid and extensive in transgenics exposed to the aeroallergen, but even after treatment with antigen over many months these mice show no evidence of respiratory distress or pathology. Helminth-infected IL-5 transgenics and their non-transgenic littermates develop similar inflammatory responses at mucosal sites and are comparable for a number of T cell and antibody responses, but they differ considerably in their ability to clear some parasite species. The life-cycle of Nippostrongylus brasiliensis is significantly inhibited in IL-5 transgenics, but that of Toxocara canis is not. Our results also suggest that eosinophilia and/or over-expression of IL-5 may actually impair host resistance to Schistosoma mansoni and Trichinella spiralis. The pathogenesis of diseases in which eosinophils are involved may therefore be more complex than previously thought.

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The HUPO Proteomics Standards Initiative has developed several standardized data formats to facilitate data sharing in mass spectrometry (MS)-based proteomics. These allow researchers to report their complete results in a unified way. However, at present, there is no format to describe the final qualitative and quantitative results for proteomics and metabolomics experiments in a simple tabular format. Many downstream analysis use cases are only concerned with the final results of an experiment and require an easily accessible format, compatible with tools such as Microsoft Excel or R. We developed the mzTab file format for MS-based proteomics and metabolomics results to meet this need. mzTab is intended as a lightweight supplement to the existing standard XML-based file formats (mzML, mzIdentML, mzQuantML), providing a comprehensive summary, similar in concept to the supplemental material of a scientific publication. mzTab files can contain protein, peptide, and small molecule identifications together with experimental metadata and basic quantitative information. The format is not intended to store the complete experimental evidence but provides mechanisms to report results at different levels of detail. These range from a simple summary of the final results to a representation of the results including the experimental design. This format is ideally suited to make MS-based proteomics and metabolomics results available to a wider biological community outside the field of MS. Several software tools for proteomics and metabolomics have already adapted the format as an output format. The comprehensive mzTab specification document and extensive additional documentation can be found online.

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Cell separation, or abscission, is a highly specialized process in plants that facilitates remodeling of their architecture and reproductive success. Because few genes are known to be essential for organ abscission, we conducted a screen for mutations that alter floral organ shedding in Arabidopsis. Nine recessive mutations that block shedding were found to disrupt the function of an ADP-ribosylation factor-GTPase-activating protein (ARF-GAP) we have named NEVERSHED (NEV). As predicted by its homology to the yeast Age2 ARF-GAP and transcriptional profile, NEV influences other aspects of plant development, including fruit growth. Co-localization experiments carried out with NEV-specific antiserum and a set of plant endomembrane markers revealed that NEV localizes to the trans-Golgi network and endosomes in Arabidopsis root epidermal cells. Interestingly, transmission electron micrographs of abscission zone regions from wild-type and nev flowers reveal defects in the structure of the Golgi apparatus and extensive accumulation of vesicles adjacent to the cell walls. Our results suggest that NEV ARF-GAP activity at the trans-Golgi network and distinct endosomal compartments is required for the proper trafficking of cargo molecules required for cell separation.

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We have previously reported (Dobreva, I., Waeber, G., Mooser, V., James, R. W., and Widmann, C. (2003) J. Lipid Res. 44, 2382-2390) that low density lipoproteins (LDLs) induce activation of the p38 MAPK pathway, resulting in fibroblast spreading and lamellipodia formation. Here, we show that LDL-stimulated fibroblast spreading and wound sealing are due to secretion of a soluble factor. Using an antibody-based human protein array, interleukin-8 (IL-8) was identified as the main cytokine whose concentration was increased in supernatants from LDL-stimulated cells. Incubation of supernatants from LDL-treated cells with an anti-IL-8 blocking antibody completely abolished their ability to induce cell spreading and mediate wound closure. In addition, fibroblasts treated with recombinant IL-8 spread to the same extent as cells incubated with LDL or supernatants from LDL-treated cells. The ability of LDL and IL-8 to induce fibroblast spreading was mediated by the IL-8 receptor type II (CXCR-2). Furthermore, LDL-induced IL-8 production and subsequent wound closure required the activation of the p38 MAPK pathway, because both processes were abrogated by a specific p38 inhibitor. Therefore, the capacity of LDLs to induce fibroblast spreading and accelerate wound closure relies on their ability to stimulate IL-8 secretion in a p38 MAPK-dependent manner. Regulation of fibroblast shape and migration by lipoproteins may be relevant to atherosclerosis that is characterized by increased LDL cholesterol levels, IL-8 production, and extensive remodeling of the vessel wall.

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The pathology induced by the nematode Camallanus cotti in the aquarium fishes Beta splendens (beta fish) and Poecilia reticulata (guppy) consisted of gross and microscopic lesions, the former characterized by abdominal swelling with reddish parasites protruding from the anus in both fish hosts and the latter, similar in the beta fishes and guppies, by hemorrhage, congestion, edema, a few glandular elements, and extensive erosion areas in the rectum mucosa, with a marked thickening of the wall and absence of inflammatory infiltrate. Lesions were associated with the presence of several worms attached to the wall or free in the rectal lumen. This is the second reference of the parasite in Brazil and the first report of pathological findings related to this nematode species that is also briefly redescribed and illustrated for the first time on the basis of Brazilian samples.

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DNA sequence variation has been associated with quantitative changes in molecular phenotypes such as gene expression, but its impact on chromatin states is poorly characterized. To understand the interplay between chromatin and genetic control of gene regulation, we quantified allelic variability in transcription factor binding, histone modifications, and gene expression within humans. We found abundant allelic specificity in chromatin and extensive local, short-range, and long-range allelic coordination among the studied molecular phenotypes. We observed genetic influence on most of these phenotypes, with histone modifications exhibiting strong context-dependent behavior. Our results implicate transcription factors as primary mediators of sequence-specific regulation of gene expression programs, with histone modifications frequently reflecting the primary regulatory event.

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The purpose of this study was to determine whether there were significant differences in accounting indicators when comparing sustainable enterprises to other similar companies that are not considered as sustainable. The Corporate Sustainability Index of BM (São Paulo Stock, Commodities and Futures Exchange) was the criterion selected to break down the samples into sustainable and non-sustainable enterprises. The accounting indicators were separated into two kinds: risk (dividend payout, percentage growth of assets, financial leverage, current liquidity, asset size, variability of earnings, and accounting beta) and return (ROA, ROE, asset turnover, and net margin). We individually analyzed the companies in the energy sector, followed by those in the banking sector, as well as the entire ISE portfolio as of 2008/2009, including all the sectors. Mann-Whitney tests were performed in order to verify the difference of the means between the groups (ISE and non-ISE). The results, considering the method chosen and the time span covered by the study, indicate that there are no differences between sustainable companies and the others, when they are assessed by the accounting indicators used here.