135 resultados para internalizing


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Com o substancial avanço da competitividade, crescem os interesses pela discussão de mecanismos potencializadores de implantação de novas tecnologias de gestão das operações das empresas, percebidas como um lastro de sustentação das organizações, necessário num mundo globalizado, no qual o poder de influência dos consumidores tem ganhado inegável relevância. Entretanto, a realidade tem revelado dificuldades de inclusão dessas abordagens em algumas empresas brasileiras, sobretudo naquelas de menor porte. Uma das barreiras são, indiscutivelmente, as limitações de recursos, aliadas às poucas alternativas de crédito de baixo custo disponibilizadas no mercado nacional para este segmento de empresas. Diante deste cenário, consultores independentes têm o enorme desafio de internalizar nestas organizações modelos de gestão mais coerentes com a dinâmica da economia atual, tendo como obstáculos adicionais as resistências culturais naturais à incorporação de algumas filosofias de administração modernas como o Lean e a Teoria das Restrições, questionadoras de conceitos tradicionais e detentoras de visões singulares, mas igualmente potencializadoras de resultados efetivos, a um baixo custo. Este trabalho objetivou, por um lado avaliar o contexto no qual os pequenos negócios estão inseridos, e, por outro, propor um modelo de apoio para consultoria voltado para este segmento de empresas, no qual os consultores assumem preponderantemente papeis de educador e coach, de maneira a elevar as chances não somente da implantação de técnicas mais modernas de gestão de operação, mas também de sua incorporação definitiva nestas organizações.

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Disease, injury, and age problems compromise human quality of life and continuously motivate the search for new and more efficacious therapeutic approaches. The field of Tissue Regeneration and Engineering has greatly evolved over the last years, mainly due to the combination of the important advances verified in Biomaterials Science and Engineering with those of Cell and Molecular Biology. In particular, a new and promising area arose – Nanomedicine – that takes advantage of the extremely small size and especial chemical and physical properties of Nanomaterials, offering powerful tools for health improvement. Research on Stem Cells, the self-renewing progenitors of body tissues, is also challenging to the medical and scientific communities, being expectable the appearance of new and exciting stem cell-based therapies in the next years. The control of cell behavior (namely, of cell proliferation and differentiation) is of key importance in devising strategies for Tissue Regeneration and Engineering. Cytokines, growth factors, transcription factors and other signaling molecules, most of them proteins, have been identified and found to regulate and support tissue development and regeneration. However, the application of these molecules in long-term regenerative processes requires their continuous presence at high concentrations as they usually present short half-lives at physiological conditions and may be rapidly cleared from the body. Alternatively, genes encoding such proteins can be introduced inside cells and be expressed using cell’s machinery, allowing an extended and more sustained production of the protein of interest (gene therapy). Genetic engineering of stem cells is particularly attractive because of their self-renewal capability and differentiation potential. For Tissue Regeneration and Engineering purposes, the patient’s own stem cells can be genetically engineered in vitro and, after, introduced in the body (with or without a scaffold) where they will not only modulate the behavior of native cells (stem cell-mediated gene therapy), but also directly participate in tissue repair. Cells can be genetically engineered using viral and non-viral systems. Viruses, as a result of millions of years of evolution, are very effective for the delivery of genes in several types of cells, including cells from primary sources. However, the risks associated with their use (like infection and immunogenic reactions) are driving the search for non-viral systems that will efficiently deliver genetic material into cells. Among them, chemical methods that are promising and being investigated use cationic molecules as carriers for DNA. In this case, gene delivery and gene expression level remain relatively low when primary cells are used. The main goal of this thesis was to develop and assess the in vitro potential of polyamidoamine (PAMAM) dendrimers based carriers to deliver genes to mesenchymal stem cells (MSCs). PAMAM dendrimers are monodispersive, hyperbranched and nanospherical molecules presenting unique characteristics that make them very attractive vehicles for both drug and gene delivery. Although they have been explored for gene delivery in a wide range of cell lines, the interaction and the usefulness of these molecules in the delivery of genes to MSCs remains a field to be explored. Adult MSCs were chosen for the studies due to their potential biomedical applications (they are considered multipotent cells) and because they present several advantages over embryonic stem cells, such as easy accessibility and the inexistence of ethical restrictions to their use. This thesis is divided in 5 interconnected chapters. Chapter I provides an overview of the current literature concerning the various non-viral systems investigated for gene delivery in MSCs. Attention is devoted to physical methods, as well as to chemical methods that make use of polymers (natural and synthetic), liposomes, and inorganic nanoparticles as gene delivery vectors. Also, it summarizes the current applications of genetically engineered mesenchymal stem cells using non-viral systems in regenerative medicine, with special focus on bone tissue regeneration. In Chapter II, the potential of native PAMAM dendrimers with amine termini to transfect MSCs is evaluated. The level of transfection achieved with the dendrimers is, in a first step, studied using a plasmid DNA (pDNA) encoding for the β-galactosidase reporter gene. The effect of dendrimer’s generation, cell passage number, and N:P ratio (where N= number of primary amines in the dendrimer; P= number of phosphate groups in the pDNA backbone) on the level of transfection is evaluated, being the values always very low. In a second step, a pDNA encoding for bone morphogenetic protein-2, a protein that is known for its role in MSCs proliferation and differentiation, is used. The BMP-2 content produced by transfected cells is evaluated by an ELISA assay and its effect on the osteogenic markers is analyzed through several classical assays including alkaline phosphatase activity (an early marker of osteogenesis), osteocalcin production, calcium deposition and mineralized nodules formation (late osteogenesis markers). Results show that a low transfection level is enough to induce in vitro osteogenic differentiation in MSCs. Next, from Chapter III to Chapter V, studies are shown where several strategies are adopted to change the interaction of PAMAM dendrimers with MSCs cell membrane and, as a consequence, to enhance the levels of gene delivery. In Chapter III, generations 5 and 6 of PAMAM dendrimers are surface functionalized with arginine-glycine-aspartic acid (RGD) containing peptides – experiments with dendrimers conjugated to 4, 8 and 16 RGD units were performed. The underlying concept is that by including the RGD integrin-binding motif in the design of the vectors and by forming RGD clusters, the level of transfection will increase as MSCs highly express integrins at their surface. Results show that cellular uptake of functionalized dendrimers and gene expression is enhanced in comparison with the native dendrimers. Furthermore, gene expression is dependent on both the electrostatic interaction established between the dendrimer moiety and the cell surface and the nanocluster RGD density. In Chapter IV, a new family of gene delivery vectors is synthesized consisting of a PAMAM dendrimer (generation 5) core randomly linked at the periphery to alkyl hydrophobic chains that vary in length and number. Herein, the idea is to take advantage of both the cationic nature of the dendrimer and the capacity of lipids to interact with biological membranes. These new vectors show a remarkable capacity for internalizing pDNA, being this effect positively correlated with the –CH2– content present in the hydrophobic corona. Gene expression is also greatly enhanced using the new vectors but, in this case, the higher efficiency is shown by the vectors containing the smallest hydrophobic chains. Finally, chapter V reports the synthesis, characterization and evaluation of novel gene delivery vectors based on PAMAM dendrimers (generation 5) conjugated to peptides with high affinity for MSCs membrane binding - for comparison, experiments are also done with a peptide with low affinity binding properties. These systems present low cytotoxicity and transfection efficiencies superior to those of native dendrimers and partially degraded dendrimers (Superfect®, a commercial product). Furthermore, with this biomimetic approach, the process of gene delivery is shown to be cell surface receptor-mediated. Overall, results show the potential of PAMAM dendrimers to be used, as such or modified, in Tissue Regeneration and Engineering. To our knowledge, this is the first time that PAMAM dendrimers are studied as gene delivery vehicles in this context and using, as target, a cell type with clinical relevancy. It is shown that the cationic nature of PAMAM dendrimers with amine termini can be synergistically combined with surface engineering approaches, which will ultimately result in suitable interactions with the cytoplasmic membrane and enhanced pDNA cellular entry and gene expression. Nevertheless, the quantity of pDNA detected inside cell nucleus is always very small when compared with the bigger amount reaching cytoplasm (accumulation of pDNA is evident in the perinuclear region), suggesting that the main barrier to transfection is the nuclear membrane. Future work can then be envisaged based on the versatility of these systems as biomedical molecular materials, such as the conjugation of PAMAM dendrimers to molecules able to bind nuclear membrane receptors and to promote nuclear translocation.

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O desenvolvimento de um processo democrático de avaliação institucional na UNESP, uma universidade multi-campus, envolveu três desafios: garantir o envolvimento de grupos representativos da comunidade no processo de avaliação; atribuir poder e responsabilidade a cada setor acadêmico e administrativo no processo de avaliação; criar uma cultura de auto-avaliação e reflexão que possibilitasse debate crítico e auto-gestão dos projetos acadêmicos. Com base nos termos de referência estabelecidos pela comunidade a CPA desenvolveu uma metodologia de avaliação democrática e investigativa, orientada para a auto-gestão e de natureza quali-quantitativa. Fundamentada em três enfoques teóricos de avaliação, o democrático, o de tomada de decisão e o crítico o processo envolveu três funções: a diagnóstica, a formativo-reflexiva e a de revisão crítica. Atualmente os usos dos resultados da avaliação para orientar políticas e decisões acadêmicas, especialmente nos cursos de graduação, evidenciam avanços no processo de internalização de cultura de avaliação orientada para auto-gestão.

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Includes bibliography

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No Brasil onde a hanseníase é endêmica e onde a infecção pelo HIV continua expandindo-se e interiorizando-se, espera-se encontrar um aumento da prevalência de indivíduos convivendo simultaneamente com hanseníase e HIV/aids, porém são poucos os relatos sobre o dano neurológico que essa sobreposição pode causar. O objetivo deste estudo foi investigar o dano neural hansenico em pacientes hansenianos coinfectados com o vírus da imunodeficiência humana, comparando com hansenianos não coinfectados no inicio do tratamento e por ocasião da alta, através de duas coortes clínicas. A amostra constou de 99 pacientes dos quais 46 possuíam coinfecção MH/HIV e 53 apenas a hanseníase, esses pacientes foram atendidos no ambulatório do Núcleo de Medicina Tropical e avaliados pela Técnica Simplificada durante seis anos. Como resultado houve predominância do sexo masculino, faixa etária entre 15 e 45 anos e a procedência da Região Metropolitana de Belém. No grupo coinfecção MH/HIV houve predominância dos pacientes Paucibacilares e nestes a presença de neurite, alteração de sensibilidade, alteração motora, presença de incapacidade e de dano neural foi superior nesse que no grupo MH. Quando comparado com o grupo MH predominou pacientes Multibacilares e nestes a presença de neurite, alteração de sensibilidade, alteração motora, presença de incapacidade e de dano neural foi superior nesse que no grupo coinfectados MH/HIV. No acompanhamento dos pacientes coinfectados MH/HIV houve uma pequena redução da incapacidade e do dano neural, enquanto no acompanhamento do grupo MH a presença de incapacidade se manteve e o dano neural aumentou. A análise de sobrevivência de Kaplan-Meier identificou que nos pacientes MH houve a manutenção da chance de o paciente permanecer sem dano neural, já no grupo dos pacientes coinfectados, observou-se uma redução na chance de o paciente se manter sem dano neural ao término do tratamento. Dessa forma conclui-se que o dano neural comporta-se de maneira diferente nos dois grupos, predominando no grupo coinfectado nos pacientes paucibacilares e nos não coinfectados nos pacientes multibacilares, porém com a mesma gravidade, o que é preocupante uma vez que diagnosticar esse dano no inicio do aparecimento da hanseníase ainda é um problema para a saúde pública.

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Pós-graduação em Psicologia do Desenvolvimento e Aprendizagem - FC

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Neste estudo, tem-se como objetivo analisar e discutir crenças, valores e aspectos práticos, considerando que a internalização dos gastos decorrentes do descarte do produto e/ou embalagens deve nortear a gestão de custos de produção de uma empresa. Por tratar-se de área do conhecimento ainda carente de estudos e sem solução consensual por parte de agentes do mercado, realizou-se um ensaio teórico em que são apresentados e discutidos posicionamentos, práticas e ações com potencial para mitigar os efeitos da degradação ambiental decorrentes de descartes inapropriados. Para isso são propostas ações por parte de empresas e de iniciativas voluntárias em negociações de títulos financeiros de compensação das externalidades, os quais foram denominados de créditos de internalização de custos privados (CICPs). Considera-se que o desenvolvimento com sustentabilidade é um processo que envolve negociações entre empresas, governos e sociedade civil, pois as políticas e metas não devem ser apenas economicamente viáveis, mas socialmente justas, ambientalmente corretas e culturalmente compartilhadas.

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Scopo del nostro lavoro è stato descrivere ed inquadrare gli aspetti psico-comportamentali e la qualità di vita della narcolessia in età evolutiva. Metodi: Abbiamo pertanto disegnato uno studio caso-controllo comprendente 30 pazienti narcolettici, 39 epilettici, e 39 controlli sani, appaiati per sesso e età. Risultati: La nostra popolazione di bambini e adolescenti affetti da narcolessia mostra un aumento delle problematiche internalizzanti. I due gruppi patologici hanno in comune punteggi più elevati rispetto ai controlli per i disturbi d’ansia, le difficoltà attentive e di socializzazione, i disturbi oppositivo-provocatori. Ciò che distingue, invece, i pazienti narcolettici, sono gli aspetti di ritiro e depressione, la tendenza alla somatizzazione, i problemi del pensiero ed i disturbi affettivi. Fattori di rischio psicopatologici per i giovani narcolettici sono risultati essere l’esordio precoce, il ritardo diagnostico, il sonno notturno disturbato, la minor latenza di sonno all’addormentamento, un maggior numero di SOREMP all’MSLT. Dall’altro lato la terapia farmacologica, un maggior numero di sonnellini spontanei e la durata di malattia, sembrano influenzare positivamente l’evoluzione comportamentale. La salute psicosociale dei giovani narcolettici, inoltre, risulta essere peggiore rispetto ai controlli sani, mentre la salute fisica non mostra differenze. I problemi internalizzanti influenzano negativamente tutti gli ambiti della salute di questi ragazzi, mentre la durata di malattia sembra migliorare il funzionamento scolastico. Conclusioni: Il nostro lavoro conferma che i giovani narcolettici presentano un maggior rischio psicopatologico sia rispetto ai controlli sani sia rispetto un’altra patologia neurologica cronica. Se da un lato alcuni aspetti comportamentali possono essere giustificati come una reazione adattativa verso una patologia neurologica invalidante, dall’altro un quadro distimico caratterizzato da ritiro e lamentele somatiche, sembra essere tipico dei bambini ed adolescenti narcolettici.

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Emotional intelligence (EI) represents an attribute of contemporary attractiveness for the scientific psychology community. Of particular interest for the present thesis are the conundrum related to the representation of this construct conceptualized as a trait (i.e., trait EI), which are in turn reflected in the current lack of agreement upon its constituent elements, posing significant challenges to research and clinical progress. Trait EI is defined as an umbrella personality-alike construct reflecting emotion-related dispositions and self-perceptions. The Trait Emotional Intelligence Questionnaire (TEIQue) was chosen as main measure, given its strong theoretical and psychometrical basis, including superior predictive validity when compared to other trait EI measures. Studies 1 and 2 aimed at validating the Italian 153-items forms of the TEIQue devoted to adolescents and adults. Analyses were done to investigate the structure of the questionnaire, its internal consistencies and gender differences at the facets, factor, and global level of both versions. Despite some low reliabilities, results from Studies 1 and 2 confirm the four-factor structure of the TEIQue. Study 3 investigated the utility of trait EI in a sample of adolescents over internalizing conditions (i.e., symptoms of anxiety and depression) and academic performance (grades at math and Italian language/literacy). Beyond trait EI, concurrent effects of demographic variables, higher order personality dimensions and non-verbal cognitive ability were controlled for. Study 4a and Study 4b addressed analogue research questions, through a meta-analysis and new data in on adults. In the latter case, effects of demographics, emotion regulation strategies, and the Big Five were controlled. Overall, these studies showed the incremental utility of the TEIQue in different domains beyond relevant predictors. Analyses performed at the level of the four-TEIQue factors consistently indicated that its predictive effects were mainly due to the factor Well-Being. Findings are discussed with reference to potential implication for theory and practice.

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Sphingosine-1-phosphate (S1P) acts as high affinity agonist at specific G-protein-coupled receptors, S1P(1-5), that play important roles e.g. in the cardiovascular and immune systems. A S1P receptor modulating drug, FTY720 (fingolimod), has been effective in phase III clinical trials for multiple sclerosis. FTY720 is a sphingosine analogue and prodrug of FTY720-phosphate, which activates all S1P receptors except S1P(2) and disrupts lymphocyte trafficking by internalizing the S1P(1) receptor. Cis-4-methylsphingosine (cis-4M-Sph) is another synthetic sphingosine analogue that is readily taken up by cells and phosphorylated to cis-4-methylsphingosine-1-phosphate (cis-4M-S1P). Therefore, we analysed whether cis-4M-Sph interacted with S1P receptors through its metabolite cis-4M-S1P in a manner similar to FTY720. Indeed, cis-4M-Sph caused an internalization of S1P receptors, but differed from FTY720 as it acted on S1P(2) and S1P(3) and only weakly on S1P(1), while FTY720 internalized S1P(1) and S1P(3) but not S1P(2). Consequently, pre-incubation with cis-4M-Sph specifically desensitized S1P-induced [Ca(2+)](i) increases, which are mediated by S1P(2) and S1P(3), in a time- and concentration-dependent manner. This effect was not shared by sphingosine or FTY720, indicating that metabolic stability and targeting of S1P(2) receptors were important. The desensitization of S1P-induced [Ca(2+)](i) increases was dependent on the expression of SphKs, predominantly of SphK2, and thus mediated by cis-4M-S1P. In agreement, cis-4M-S1P was detected in the supernatants of cells exposed to cis-4M-Sph. It is concluded that cis-4M-Sph, through its metabolite cis-4M-S1P, acts as a S1P receptor modulator and causes S1P receptor internalization and desensitization. The data furthermore help to define requirements for sphingosine kinase substrates as S1P receptor modulating prodrugs.

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The uptake of radiolabeled somatostatin analogs by tumor cells through receptor-mediated internalization is a critical process for the in vivo targeting of tumoral somatostatin receptors. In the present study, the somatostatin receptor internalization induced by a variety of somatostatin analogs was measured with new immunocytochemical methods that allow characterization of trafficking of the somatostatin receptor subtype 2 (sst2), somatostatin receptor subtype 3 (sst3), and somatostatin receptor subtype 5 (sst5) in vitro at the protein level. METHODS: Human embryonic kidney 293 (HEK293) cells expressing the sst2, sst3, or the sst5 were used in a morphologic immunocytochemical internalization assay using specific sst2, sst3 and sst5 antibodies to qualitatively and quantitatively determine the capability of somatostatin agonists or antagonists to induce somatostatin receptor internalization. In addition, the internalization properties of a selection of these agonists have been compared and quantified in sst2-expressing CHO-K1 cells using an ELISA. RESULTS: Agonists with a high sst2-binding affinity were able to induce sst2 internalization in the HEK293 and CHO-K1 cell lines. New sst2 agonists, such as Y-DOTA-TATE, Y-DOTA-NOC, Lu-DOTA-BOC-ATE (where DOTA is 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid; TATE is [Tyr3, Thr8]-octreotide; NOC is [1-NaI3]-octreotide; and BOC-ATE is [BzThi3, Thr8]-octreotide), iodinated sugar-containing octreotide analogs, or BIM-23244 were considerably more potent in internalizing sst2 than was DTPA-octreotide (where DTPA is diethylenetriaminepentaacetic acid). Similarly, compounds with high sst3 affinity such as KE108 were able to induce sst3 internalization. In sst2- or sst3-expressing cell lines, agonist-induced receptor internalization was efficiently abolished by sst2- or sst3-selective antagonists, respectively. Antagonists alone had no effect on sst2 or sst3 internalization. We also showed that somatostatin-28 and somatostatin-14 can induce sst5 internalization. Unexpectedly, however, potent sst5 agonists such as KE108, BIM-23244, and L-817,818 were not able to induce sst5 internalization under the same conditions. CONCLUSION: Using sensitive and reproducible immunocytochemical methods, the ability of various somatostatin analogs to induce sst2, sst3, and sst5 internalization has been qualitatively and quantitatively determined. Whereas all agonists triggered sst2 and sst3 internalization, sst5 internalization was induced by natural somatostatin peptides but not by synthetic high-affinity sst5 agonists. Such assays will be of considerable help for the future characterization of ligands foreseen for nuclear medicine applications.