980 resultados para Functional-characteristics
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Large numbers and functionally competent T cells are required to protect from diseases for which antibody-based vaccines have consistently failed (1), which is the case for many chronic viral infections and solid tumors. Therefore, therapeutic vaccines aim at the induction of strong antigen-specific T-cell responses. Novel adjuvants have considerably improved the capacity of synthetic vaccines to activate T cells, but more research is necessary to identify optimal compositions of potent vaccine formulations. Consequently, there is a great need to develop accurate methods for the efficient identification of antigen-specific T cells and the assessment of their functional characteristics directly ex vivo. In this regard, hundreds of clinical vaccination trials have been implemented during the last 15 years, and monitoring techniques become more and more standardized.
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The immune system must be tightly held in check to avoid bystander tissue damage as well as autoreactivity caused by overwhelming immune reactions. A novel family of immunoregulatory, carbohydrate-binding receptors, the Siglecs (sialic acid binding immunoglobulin-like lectins), has received particular attention in light of their capacity to mediate cell death, anti-proliferative effects and to regulate a variety of cellular activities. Siglec receptors are mainly expressed on leukocytes in a cell type-specific and differentiation-dependent manner. Siglecs might potentially be exploited as targets of novel immune- and glycotherapeutics for cell-directed therapies in autoimmune and allergic diseases, as well as in haematologic malignancies. Here we present novel insights on structural and functional characteristics, expression patterns and evolutionary aspects of Siglecs and their ligands. Pharmacological strategies using Siglec agonistic cross-linking therapeutics, such as monoclonal or engineered antibodies, intravenous immunoglobulin (IVIG), or glycomimetics are discussed. Modulation of immune responses by targeting Siglecs using agonistic or antagonistic therapeutics may have important clinical implications and may pave the way for novel pharmacological avenues for the treatment of autoimmune and allergic diseases or for tumor immunotherapy.
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Background The diagnostic and clinical overlap between schizophrenia and schizoaffective disorder is an important nosological issue in psychiatry that is yet to be resolved. The aim of this study was to compare the clinical and functional characteristics of an epidemiological treated cohort of first episode patients with an 18-month discharge diagnosis of schizophrenia (FES) or schizoaffective disorder (FESA). Methods This study was part of the larger First Episode Psychosis Outcome Study (FEPOS) which involved a medical file audit study of all 786 patients treated at the Early Psychosis Prevention and Intervention Centre between 1998 and 2000. Of this cohort, 283 patients had an 18-month discharge diagnosis of FES and 64 had a diagnosis of FESA. DSM-IV diagnoses and clinical and functional ratings were derived and validated by two consultant psychiatrists. Results Compared to FES patients, those with FESA were significantly more likely to have a later age of onset (p=.004), longer prodrome (p=.020), and a longer duration of untreated psychosis (p<.001). At service entry, FESA patients presented with a higher illness severity (p=.020), largely due to the presence of more severe manic symptoms (p<.001). FESA patients also had a greater number of subsequent inpatient admissions (p=.017), had more severe depressive symptoms (p=.011), and higher levels of functioning at discharge. Discussion The findings support the notion that these might be considered two discernable disorders; however, further research is required to ascertain the ways and extent to which these disorders are discriminable at presentation and over time.
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Depressive symptoms in 'non-affective' first episode schizophrenia spectrum disorders (FES) are common, but poorly understood, resulting in a range of conceptual and clinical management issues. This study had three aims: (i) to determine the prevalence of moderate to severe depressive symptoms (defined as a Clinical Global Impressions Scale-Bipolar Disorder (CGI-BP depression) score >3) in a large representative sample of FES patients; (ii) to compare the clinical and functional characteristics of FES patients with and without these depressive symptoms at service entry; and (iii) to compare the characteristics of FES patients with and without persistent depressive symptoms.
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Context During the past 2 decades, a major transition in the clinical characterization of psychotic disorders has occurred. The construct of a clinical high-risk (HR) state for psychosis has evolved to capture the prepsychotic phase, describing people presenting with potentially prodromal symptoms. The importance of this HR state has been increasingly recognized to such an extent that a new syndrome is being considered as a diagnostic category in the DSM-5. Objective To reframe the HR state in a comprehensive state-of-the-art review on the progress that has been made while also recognizing the challenges that remain. Data Sources Available HR research of the past 20 years from PubMed, books, meetings, abstracts, and international conferences. Study Selection and Data Extraction Critical review of HR studies addressing historical development, inclusion criteria, epidemiologic research, transition criteria, outcomes, clinical and functional characteristics, neurocognition, neuroimaging, predictors of psychosis development, treatment trials, socioeconomic aspects, nosography, and future challenges in the field. Data Synthesis Relevant articles retrieved in the literature search were discussed by a large group of leading worldwide experts in the field. The core results are presented after consensus and are summarized in illustrative tables and figures. Conclusions The relatively new field of HR research in psychosis is exciting. It has the potential to shed light on the development of major psychotic disorders and to alter their course. It also provides a rationale for service provision to those in need of help who could not previously access it and the possibility of changing trajectories for those with vulnerability to psychotic illnesses.
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Osseointegration of titanium dental implants into the jaw bone, which is required for maintenance of the implant in the jaw, results in ankylosis. Dental implants are therefore very unlike natural teeth, which exhibit significant movement in response to mechanical forces. The ability to generate periodontal ligament (PDL) tissues onto dental implants would better mimic the functional characteristics of natural teeth, and would likely improve implant duration and function. OBJECTIVES: The objective of this study was to investigate the feasibility of bioengineering PDL tissues onto titanium implant surfaces. METHODS: Bilateral maxillary first and second molars of 8-week old rats were extracted and used to generate single cell suspensions of PDL tissues, which were expanded in culture. Immunohistochemistry and RT-PCR were used to identify putative PDL progenitor/stem cell populations and characterize stem cell properties, including self-renewal, multipotency and stem cell maker expression. Cultured rPDL cells were harvested at third passage, seeded onto Matrigel-coated titanium implants (1.75 mm x 1 mm), and placed into healed M1/M2 extraction sites. Non-cell seeded Matrigel-coated titanium implants served as negative controls. Implants were harvested after 8, 12, or 18 weeks. RESULTS: Cultured rPDL cells expressed the mesenchymal stem-cell marker STRO-1. Under defined culture conditions, PDL cells differentiated into adipogenic, neurogenic and osteogenic lineages. While control implants were largely surrounded by alveolar bone, experimental samples exhibited fibrous PDL-like tissues, and perhaps cementum, on the surface of experimental implants. CONCLUSIONS: PDL contains stem cells that can generate cementum/PDL-like tissue in vivo. Transplantation of these cells might hold promise as a therapeutic approach for the bioengineering of PDL tissues onto titanium implant. Further refinement of this method will likely result in improved dental implant strategies for use of autologous PDL tissue regeneration in humans. This research was supported by CIMIT, and NIH/NIDCR grant DE016132 (PCY), and TEACRS (YL).
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As awareness of potential human and environmental impacts from toxins has increased, so has the development of innovative sensors. Bacteriorhodopsin (bR) is a light activated proton pump contained in the purple membrane (PM) of the bacteria Halobacterium salinarum. Bacteriorhodopsin is a robust protein which can function in both wet and dry states and can withstand extreme environmental conditions. A single electron transistor(SET) is a nano-scale device that exploits the quantum mechanical properties of electrons to switch on and off. SETs have tremendous potential in practical applications due to their size, ultra low power requirements, and electrometer-like sensitivity. The main goal of this research was to create a bionanohybrid device by integrating bR with a SET device. This was achieved by a multidisciplinary approach. The SET devices were created by a combination of sputtering, photolithography, and focused ion beam machining. The bionanomaterial bacteriorhodopsin was created through oxidative fermentation and a series of transmembrane purification processes. The bR was then integrated with the SET by electrophoretic deposition, creating a bionanohybrid device. The bionanohybrid device was then characterized using a semiconductor parametric analyzer. Characterization demonstrated that the bR modulated the operational characteristics of the SET when bR was activated with light within its absorbance spectrum. To effectively integrate bacteriorhodopsin with microelectromechanical systems (MEMS) and nanoelectromechanical systems (NEMS), it is critical to know the electrical properties of the material and to understand how it will affect the functionality of the device. Tests were performed on dried films of bR to determine if there is a relationship between inductance, capacitance, and resistance (LCR) measurements and orientation, light-on/off, frequency, and time. The results indicated that the LCR measurements of the bR depended on the thickness and area of the film, but not on the orientation, as with other biological materials such as muscle. However, there was a transient LCR response for both oriented and unoriented bR which depended on light intensity. From the impedance measurements an empirical model was suggested for the bionanohybrid device. The empirical model is based on the dominant electrical characteristics of the bR which were the parallel capacitance and resistance. The empirical model suggests that it is possible to integrate bR with a SET without influencing its functional characteristics.
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Through alternative splicing, multiple different transcripts can be generated from a single gene. Alternative splicing represents an important molecular mechanism of gene regulation in physiological processes such as developmental programming as well as in disease. In cancer, splicing is significantly altered. Tumors express a different collection of alternative spliceoforms than normal tissues. Many tumor-associated splice variants arise from genes with an established role in carcinogenesis or tumor progression, and their functions can be oncogenic. This raises the possibility that products of alternative splicing play a pathogenic role in cancer. Moreover, cancer-associated spliceoforms represent potential diagnostic biomarkers and therapeutic targets. G protein-coupled peptide hormone receptors provide a good illustration of alternative splicing in cancer. The wild-type forms of these receptors have long been known to be expressed in cancer and to modulate tumor cell functions. They are also recognized as attractive clinical targets. Recently, splice variants of these receptors have been increasingly identified in various types of cancer. In particular, alternative cholecystokinin type 2, secretin, and growth hormone-releasing hormone receptor spliceoforms are expressed in tumors. Peptide hormone receptor splice variants can fundamentally differ from their wild-type receptor counterparts in pharmacological and functional characteristics, in their distribution in normal and malignant tissues, and in their potential use for clinical applications.
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Intestinal macrophages, preferentially located in the subepithelial lamina propria, represent the largest pool of tissue macrophages in humans. As an adaptation to the local antigen- and bacteria-rich environment, intestinal macrophages exhibit several distinct phenotypic and functional characteristics. Notably, microbe-associated molecular pattern receptors, including the lipopolysaccharide (LPS) receptors CD14 and TLR4, and also the Fc receptors for IgA and IgG are absent on most intestinal macrophages under homeostatic conditions. Moreover, while macrophages in the intestinal mucosa are refractory to the induction of proinflammatory cytokine secretion, they still display potent phagocytic activity. These adaptations allow intestinal macrophages to comply with their main task, i.e., the efficient removal of microbes while maintaining local tissue homeostasis. In this paper, we review recent findings on the functional differentiation of monocyte subsets into distinct macrophage populations and on the phenotypic and functional adaptations that have evolved in intestinal macrophages in response to their antigen-rich environment. Furthermore, the involvement of intestinal macrophages in the pathogenesis of celiac disease and inflammatory bowel diseases is discussed.
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An analysis was made of composition and content of nutrients, salts, particulate and dissolved organic matter, and various plankton groups in a series of samples collected by a 140-liter sampling bottle to depth up to 150 m at 4 equatorial stations between 97° and 154°W. Large and small phytoplankton, bacteria (aggregated and dispersed), heterotrophic flagellates, infusorians, radiolarians, foraminifers, fine filter-feeders, small and large, mostly herbivorous copepods, cyclopoids, predatory calanoids, and other predators were investigated separately. Trophic relations between these elements are established from personal and published data, and rate of their metabolism and some other physiological parameters are determined. Such functional characteristics as extent of satisfaction of food requirements of organisms belonging to various trophic groups, intensity of trophic relations, balance between production and consumption by individual elements of the community, ecological efficiency, and net and specific production of the groups distinguished, of individual trophic levels, of total zooplankton, and of the community as a whole are calculated. Variations of these characteristics along the equator with decreasing upwelling intensity are examined and their possible causes and mechanisms are discussed.
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In the near future, the marine environment is likely to be subjected to simultaneous increases in temperature and decreased pH. The potential effects of these changes on intertidal, meiofaunal assemblages were investigated using a mesocosm experiment. Artificial Substrate Units containing meiofauna from the extreme low intertidal zone were exposed for 60 days to eight experimental treatments (four replicates for each treatment) comprising four pH levels: 8.0 (ambient control), 7.7 & 7.3 (predicted changes associated with ocean acidification), and 6.7 (CO2 point-source leakage from geological storage), crossed with two temperatures: 12 °C (ambient control) and 16 °C (predicted). Community structure, measured using major meiofauna taxa was significantly affected by pH and temperature. Copepods and copepodites showed the greatest decline in abundance in response to low pH and elevated temperature. Nematodes increased in abundance in response to low pH and temperature rise, possibly caused by decreased predation and competition for food owing to the declining macrofauna density. Nematode species composition changed significantly between the different treatments, and was affected by both seawater acidification and warming. Estimated nematode species diversity, species evenness, and the maturity index, were substantially lower at 16 °C, whereas trophic diversity was slightly higher at 16 °C except at pH 6.7. This study has demonstrated that the combination of elevated levels of CO2 and ocean warming may have substantial effects on structural and functional characteristics of meiofaunal and nematode communities, and that single stressor experiments are unlikely to encompass the complexity of abiotic and biotic interactions. At the same time, ecological interactions may lead to complex community responses to pH and temperature changes in the interstitial environment.
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El WCTR es un congreso de reconocido prestigio internacional en el ámbito de la investigación del transporte y aunque las actas publicadas están en formato digital y sin ISSN ni ISBN, lo consideramos lo suficientemente importante como para que se considere en los indicadores. Policies trying to increase walking within urban mobility modal split usually highlight the importance of the functional patterns and the environmental quality of the urban space as major drivers of citizens modal choices. Functional characteristics would be mainly associated to an appropriate mix of land uses within neighbourhoods, whereas environmental quality would be associated to the characteristics of urban spaces. The purpose of this research is threefold: first, to identify relevant proxy indicators, which could characterize pedestrian-friendly land use mix and environmental quality. Second, to assess, for both traits, existing disparities among neighbourhoods in a major metropolitan area. And finally, to explore the association between both indicators and children mobility patterns: according to their built environment, which neighbourhoods have a greater proportion of children and, how is their mobility? Using data from the 2004 household mobility survey in the 128 neighbourhoods of the municipality of Madrid, this paper concludes that potentially favourable conditions at the neighbourhood level seem to have only a modest influence in,mobility patterns , in terms of both, selection of closer destinations and a higher share of walking within modal split. The citys policy choices, with intensive investment in road and public transport infrastructure may explain why short-distance mobility is not as important as it could have been expected in those neighbourhoods with more pedestrian-friendly conditions. The metropolitan transport system is providing mobility conditions, which make far-away destinations attractive to most citizens.
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Policies trying to increase walking within urban mobility modal split usually highlight the importance of the functional patterns and the environmental quality of the urban space as major drivers of citizens modal choices. Functional characteristics would be mainly associated to an appropriate mix of land uses within neighbourhoods, whereas environmental quality would be associated to the characteristics of urban spaces. The purpose of this research is threefold: first, to identify relevant proxy indicators, which could characterize pedestrian-friendly land use mix and environmental quality. Second, to assess, for both traits, existing disparities among neighbourhoods in a major metropolitan area. And finally, to explore the association between both indicators and children mobility patterns: according to their built environment, which neighbourhoods have a greater proportion of children and, how is their mobility? Using data from the 2004 household mobility survey in the 128 neighbourhoods of the municipality of Madrid, this paper concludes that potentially favourable conditions at the neighbourhood level seem to have only a modest influence in,mobility patterns , in terms of both, selection of closer destinations and a higher share of walking within modal split. The city s policy choices, with intensive investment in road and public transport infrastructure may explain why short-distance mobility is not as important as it could have been expected in those neighbourhoods with more pedestrian-friendly conditions. The metropolitan transport system is providing mobility conditions, which make far-away destinations attractive to most citizens.
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El presente texto se ha desarrollado como Proyecto Fin de Grado en la Escuela Técnica Superior de Ingeniería y Sistemas de Telecomunicación de la Universidad Politécnica de Madrid en colaboración con la Consultora Tecnológica everis. El mismo tiene como objetivo realizar un estudio de los requisitos necesarios para poder desplegar un servicio que permita ofrecer a las Operadoras Móviles Virtuales (OMV) soporte técnico a sus clientes a través de las redes sociales. Este módulo establecerá una nueva vía de comunicación entre el consumidor y el cliente de la OMV con la propia OMV, el cual se caracterizará por una alta accesibilidad y una gran rapidez en el servicio permitiendo de este modo, una mayor satisfacción del cliente con su operador móvil y por tanto de una nueva vía para conseguir la fidelización del mismo y la captación de nuevos clientes. Para ello, este proyecto se lleva a cabo sobre el sistema de información 4mobile el cual es comercializado por la mencionada Consultora Tecnológica. Este sistema consiste en una plataforma web la cual permite cubrir todos los procesos de negocio comunes que un OMV necesita gestionar. Es por ello, que el mencionado estudio se centra en la evaluación de los aspectos necesarios para la integración de un módulo de estas características dentro de la plataforma de 4mobile. Este módulo, estará basado en una herramienta software que permitirá gestionar el ciclo de vida completo del comentario realizado por el cliente a través de una red social, desde que es publicado por el cliente, hasta que se haya respondido al mismo y su solución sea considerada como satisfactoria por el cliente. Por ello, y de cara a definir correctamente esta herramienta, será necesario un detallado análisis el cual recoja diversos aspectos y que a lo largo del texto, será denominado como Plan de Marketing de Medios Sociales (PMMS). Estos aspectos versarán tanto de las necesidades tecnológicas para su mencionada integración, como de la serie de características funcionales que una solución basada en servicio técnico a través de las redes sociales deberá poseer con el objetivo de ofrecer un servicio técnico de calidad. Finalmente, estas funcionalidades y necesidades tecnológicas se expondrán en forma de propuesta a everis para su integración en la plataforma 4mobile junto con un análisis de diseño a alto nivel software de la solución a desarrollar. ABSTRACT. This text has been developed as Final Degree Project in the Escuela Técnica Superior de Ingeniería y Sistemas de Telecomunicación de la Universidad Politécnica de Madrid in collaboration with the Technology Consultant everis, aims to conduct a study of how to provide technical support through social networks and the evaluation of the integration of a social support module within the system platform 4mobile, which cover all business processes that need to manage a Mobile Virtual Network Operator (MVNO), which is marketed by above-mentioned consultant . This module will establish a new communication channel between the consumer and the client with the OMV and itself, which is characterized by high accessibility and great fast service. Thus will allow a higher customer satisfaction with him service and thus a new way to get the same loyalty and attract new customers To this end, this project is performed on the information system 4mobile which is marketed by the consulting part thereof everis. This system is a platform to cover all business processes that need to manage an MVNO. Therefore, the mentioned study focuses on the evaluation of the elements necessary for integrating module these features within the platform 4mobile. This module will be based on a software tool for managing the entire lifecycle of the comment made by the customer via social networking, from the moment it is published, until it has been respond and their solution is considered satisfactory for the customer. So, in order to properly define this tool, a detailed analysis which will be necessary to collect various aspects and throughout the text, it will be referred to as Plan of Social Media Marketing (PMMS). These aspects will be address both: the technological needs for the mentioned integration, and the number of functional characteristics-based service through social networking solution, as this must in order to provide a quality service Finally, these goals and requirements will be discussed as everis offer for integration into the platform 4mobile analysis along with a high level of software design to develop the solution.
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Among the different optical modulator technologies available such as polymer, III-V semiconductors, Silicon, the well-known Lithium Niobate (LN) offers the best trade-off in terms of performances, ease of use, and power handling capability [1-9]. The LN technology is still widely deployed within the current high data rate fibre optic communications networks. This technology is also the most mature and guarantees the reliability which is required for space applications [9].In or der to fulfil the target specifications of opto-microwave payloads, an optimization of the design of a Mach-Zehnder (MZ) modulator working at the 1500nm telecom wavelength was performed in the frame of the ESA-ARTES "Multi GigaHertz Optical Modulator" (MGOM) project in order to reach ultra-low optical insertion loss and low effective driving voltage in the Ka band. The selected modulator configuration was the X-cut crystal orientation, associated to high stability Titanium in-diffusion process for the optical waveguide. Starting from an initial modulator configuration exhibiting 9 V drive voltage @ 30 GHz, a complete redesign of the coplanar microwave electrodes was carried out in order to reach a 6 V drive voltage @ 30GHz version. This redesign was associated to an optimization of the interaction between the optical waveguide and the electrodes. Following the optimisation steps, an evaluation program was applied on a lot of 8 identical modulators. A full characterisation was carried out to compare performances, showing small variations between the initial and final functional characteristics. In parallel, two similar modulators were submitted to both gamma (10-100 krad) and proton irradiation (10.109 p/cm²) with minor performance degradation.