983 resultados para Ativação policlonal
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Chemical modification of polymer matrices is an alternative way to change its surface properties. The introduction of sulfonic acid groups in polymer matrices alter properties such as adhesion, wettability, biocampatibility, catalytic activity, among others. This paper describes the preparation of polymeric solid acid based on the chemical modification of poly (1-fenietileno) (PS) and Poly (1-chloroethylene) (PVC) by the introduction of sulfonic acid groups and the application of these polymers as catalysts in the esterification reaction of oleic acid with methanol. The modified materials were characterized by Infrared Spectroscopy, Elemental Analysis and titration acid-base of the acid groups. All techniques confirmed the chemical changes and the presence of sulfur associated with sulfonic acid groups or sulfates. The modified polymers excellent performance in the esterification reaction of oleic acid with methanol a degree of conversion higher than 90% for all investigated polymers (modified PS and PVC (5% w / w)), with a mass ratio of oleic acid: methanol 1:10 to 100 ° C. The best performance was observed for the modified PVC catalyst (PVCS) which showed low degree of swelling during the reactions is recovered by filtration different from that observed for polystyrene sulfonate (PSS). Given these facts, the PVCS was employed as a catalyst in the esterification reaction of oleic acid in different times and different temperatures to obtain the kinetic parameters of the reaction. Experimental data show a great fit for pseudo-homogeneous model of second order and activation energy value of 41.12 kJ mol -1, below that found in the literature for the uncatalyzed reaction, 68.65 kJ mol -1 .The PVCS exhibits good catalytic activity for 3 times of reuse, with a slight decrease in the third cycle, but with a conversion of about 78%. The results show that solid polymeric acid has good chemical stability for the application in esterification reaction of commercial importance with possible application in the biodiesel production. The advantages in use of this system are the increased reaction rate at about 150 times, at these test conditions, the replacement of sulfuric acid as a catalyst for this being the most corrosive and the possibility of reuse of the polymer for several cycles.
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Introduction: The production of KPC (Klebsiella pneumoniae carbapenemase) has become an important mechanism of carbapenem-resistance among Enterobacteriaceae strains. In Brazil, KPC is already widespread and its incidence has increased significantly, reducing treatment options. The “perfect storm” combination of the absence of new drug developmentand the emergence of multidrug-resistant strains resulted in the need for the use of older drugs, with greater toxicity, such as polymyxins. Aims: To determine the occurrence of carbapenemase-producing strains in carbapenem-resistant Enterobacteriaceae isolated from patients with nosocomial infection/colonization during September/2014 to August/2015, to determine the risk factors associated with 30-day- mortality and the impact of inappropriate therapy. Materials and Methods: We performed a case control study to assess the risk factors (comorbidities, invasive procedures and inappropriate antimicrobial therapy) associated with 30-day-mortality, considering the first episode of infection in 111 patients. The resistance genes blaKPC, blaIMP, blaVIM and blaNDM-1 were detected by polymerase chain reaction technique. Molecular typing of the strains involved in the outbreak was performed by pulsed field gel electrophoresis technique. The polymyxin resistance was confirmed by the microdilution broth method. Results: 188 episodes of carbapenem-resistant Enterobacteriaceae infections/colonizations were detected; of these, 122 strains were recovered from the hospital laboratory. The presence of blaKPC gene were confirmed in the majority (74.59%) of these isolates. It was not found the presence of blaIMP , blaVIM and blaNDM-1 genes. K. pneumoniae was the most frequent microorganism (77,13%), primarily responsible for urinary tract infections (21,38%) and infections from patients of the Intensive Care Unit (ICU) (61,38%). Multivariate statistical analysis showed as predictors independently associated with mortality: dialysis and bloodstream infection. The Kaplan-Meier curve showed a lower probability of survival in the group of patients receiving antibiotic therapy inappropriately. Antimicrobial use in adult ICU varied during the study period, but positive correlation between increased incidence of strains and the consumption was not observed. In May and July 2015, the occurrence rates of carbapenem-resistant Enterobacteriaceae KPC-producing per 1000 patient-days were higher than the control limit established, confirming two outbreaks, the first caused by colistin-susceptible KPC-producing K. pneumoniae isolates, with a polyclonal profile and the second by a dominant clone of colistin-resistant (≥ 32 μg/mL) KPC-producing K. pneumoniae. The cross transmission between patients became clear by the temporal and spatial relationships observed in the second outbreak, since some patients occupied the same bed, showing problems in hand hygiene adherence among healthcare workers and inadequate terminal disinfection of environment. The outbreak was contained when the ICU was closed to new admissions. Conclusions: The study showed an endemicity of K. pneumoniae KPC-producing in adult ICU, progressing to an epidemic monoclonal expansion, resulted by a very high antibiotic consumption of carbapenems and polymyxins and facilitated by failures in control measures the unit.
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Neospora caninum is an obligate intracellular parasite classified in the phylum Apicomplexa, characterized by the presence of the apical complex composed by micronemes proteins, rhoptries and dense granules, used by parasite during the adhesion and invasion process of the host cell. This is the mean event in infection pathogenesis generated by N. caninum and other parasites from the phylum Apicomplexa, promoting influence in the parasite biology and the interface between the parasite and its host. Therefore, molecular tools have been developed in order to identify and characterize these possible virulence factors. Thus, the present study sought to establish a specific system of genetic manipulation of N. caninum, searching for the improvement of the genetics manipulation of this parasite. So, we developed genetically depleted N. caninum to Rop9 rhoptry using the pU6-Universal CRISPR-Cas9 plasmid of T. gondii modified by the insertion of Ku80. The Rop9 depleted parasite showed important during initial phase of invasion and replication of the parasite, however it was not characterized as a potential virulence fator for N. caninum. Furthermore, T. gondii proteins were expressed in N. caninum by the use of specific vectors for this parasite, showing an heterologous system for the study of Toxoplasma proteins, due to the fact that Gra15 or Gra24 of type II T. gondii and Rop16 of type I T. gondii were expressed in N. caninum tachyzoites in a stable way and keept its biological phenotype, as already presented the former parasite, that naturaly expresses these proteins. In addition, it was observed that N. caninum induced an inflammasome activation through NLRP3, ASC and Caspase-1. IL-1R/MyD88 demonstrated an indirect pathway in the control of parasite replication. Furthermore, it was observed that this activation is dependent of the potassium efflux and that different strains of N. caninum keep this activation profile. However, T. gondii strains block this activation, making necessary a prior signal in order to active the inflamosome pathway. Type I T. gondii Rop16 was identified as responsible for blocking this activation, in a dependent way to the STAT3 activation. Therefore, the development of molecular tools and their application in N. caninum may prove to be useful to identify and characterize virulent factors involved in the pathogenesis by these two protozoans.
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As técnicas nucleares, com ênfase a técnica conhecida como TLA - Thin Layer Activation, tem sido utilizada com sucesso e contribuído significativamente para o estudo de sistemas tribológicos, na análise e medição de desgaste para profundidades na ordem de grandeza de 10 µm apesar potencialmente poder aplicadas a espessuras de dezenas de milímetros. Esta limitação é intrínseca da técnica utilizada na ativação da camada superficial da peça ou elemento a ser investigado, que consiste na aplicação direta de um feixe de partículas carregadas a uma determinada energia, equivalente a máxima seção de choque do material a fim de obter uma taxa ativação constante ao longo de uma determinada espessura ou utilizando uma energia menor que este valor para se obter uma taxa ativação linear também para uma determinada profundidade de ativação. O objetivo desse trabalho é apresentar uma nova técnica que consiste na utilização de um feixe de energia superior a energia correspondente à máxima seção de choque e aplicar um elemento degradador (Roda Degradadora) como objetivo de homogeneizar a ativação superficial ao longo da espessura da amostra, possibilitando uma melhoria na precisão da análise e possibilitando ainda um maior alcance dessa camada e aumentando a gama de aplicações possíveis dessa técnica, onde por exemplo, maiores taxas de desgaste possam ser analisadas. Após o experimento e análise dos dados constatou-se que a técnica proposta melhora a linearidade da curva que representa a taxa de ativação e aumentando significativamente a profundidade analisável podendo chegar a ordem 6 x 10 µm. Em adição este trabalho reinaugura a pesquisa em aplicações nucleares no IEN - Instituto de Engenharia Nuclear com utilização de aceleradores de partículas tipo ciclotron.
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O projeto e desenvolvimento de uma nova linha de feixe dotada de um sistema que viabilize a irradiação no Cíclotron CV-28 do Instituto de Engenharia Nuclear de alvos extensos e de geometria variável tornaram-se necessário para a realização de estudos e desenvolvimento de aplicações de técnicas nucleares e análises de materiais por ativação em condições de irradiação até então não disponíveis. Este sistema que poderá ser utilizado em irradiações com feixes de prótons, alfas, deutério e hélions (He3) a energias variáveis, é composto por dispositivos de: proteção, interceptação, colimação e medição da intensidade do feixe, de forma a possibilitar a realização de irradiações em condições controláveis e reprodutíveis. Para tanto, peças em alumínio e PVC-foram usinadas de forma a construir os componentes do sistema, notadamente colimadores com 13mm e 9mm de diâmetro, um dispositivo de colimação de quatro setores, um "beam stop", duas flanges de isolamento elétrico e um porta alvo (com janela degradadora). Identificou-se também a necessidade de se dotar o sistema aqui desenvolvido de um circuito de refrigeração próprio à água deionizada que é responsável pela refrigeração de todos os seus componentes que possam ter contato com o feixe. O sistema conta ainda com conexões para vácuo, que possibilitam fazer um pré-vácuo em sua câmara de irradiação, de forma que a mesma possa interligada a linha de transporte de feixe de Cíclotron CV-28, sem causar danos ao vácuo do mesmo. A condição para se fazer esta interligação é a obtenção de um pré-vácuo no ordem de 10-4 torr. Os resultados experimentais obtidos com a realização de irradiações de alvos metálicos especialmente desenvolvidos para testar o sistema, que é tema da presente dissertação, atestam a confiabilidade e reprodutibilidade das condições de irradiação, o que viabilizam o desenvolvimento e emprego de novas unidades de irradiação a serem incorporadas ao mesmo. Esse sistema de irradiação já está sendo utilizado na linha 2 do CV-28
Resumo:
Objetivo. Devido ao aumento da esperança de vida, os adultos com necessidades especiais vivem mais tempo, sendo os seus principais cuidadores, geralmente familiares, também mais envelhecidos. Tal situação representa novas necessidades específicas de apoio, sendo inúmeros os desafios colocados ao Serviço Social no sentido de garantir o bem-estar da pessoa com incapacidade e dos seus cuidadores. Assim, este estudo tem como objetivo realizar um levantamento das necessidades de apoio e a caraterização da rede social pessoal de apoio do cuidador informal de adultos com necessidades especiais. Participantes. A amostra é constituída por 40 cuidadores informais de adultos com necessidades especiais, integrados na resposta social “Centro de Atividades Ocupacionais-CAO” da Associação de Paralisia Cerebral de Coimbra, de ambos os sexos com idade igual ou superior a 40 anos. Material e métodos. Foi utilizado o Instrumento de Avaliação da Rede Social Pessoal e um questionário para caracterização sociodemográfica e sociofamiliar dos cuidadores, assim como para avaliação de necessidades. Resultados. Aproximadamente um terço dos cuidadores relatou a experiência de níveis moderados de sobrecarga associada à prestação de cuidados, enquanto mais de metade relatou a experiência de níveis elevados e muito elevados dessa sobrecarga; o apoio financeiro foi referido como a forma de apoio mais necessária no presente, ainda que o apoio em residência tenha sido percecionado por cerca de um terço dos cuidadores como a forma de apoio mais necessária no futuro; enquanto mais de metade considerou o apoio domiciliário e de unidade residencial (institucional). Estes cuidadores familiares referiram a "incerteza" e a "esperança" como os sentimentos mais frequentemente experienciados em relação ao futuro das suas vidas. No que respeita às redes sociais, as relações familiares são centrais a nível estrutural; em termos de caraterísticas funcionais da rede, foram observados valores mais elevados para as dimensões de reciprocidade do apoio e satisfação com a rede social. Implicações. Este estudo sublinha a importância da avaliação das necessidades de apoio dos cuidadores familiares de adultos com necessidades especiais. A sua implementação sistemática pode auxiliar a tomada de decisão baseada na evidência empírica para as intervenções do Serviço Social, tais como na planificação e gestão de respostas e serviços sociais, a par do reconhecimento e ativação dos recursos das próprias famílias, de forma a promover a eficiência dos recursos e eficácia das intervenções, focadas no bem-estar do cidadão com deficiência e das suas famílias. / Aim. The general increase in human life expectancy has resulted in greater rates of survival for adults with special care needs, as well as for their ageing family caregivers. This situation poses different and specific support needs, which represent a major challenge in social work interventions aimed at ensuring the well-being of disabled persons and their caregivers. Therefore, this study was aimed to describe the needs for support and the perceived social support network of family caregivers of adults with special care needs. Participants. The sample for this study comprised 40 family caregivers of disabled adults with special care needs, of both genders and aged 40 years old at minimum, who attended a long-term care facility at Coimbra Cerebral Palsy Association. Material and methods. Participants were administered a self-report questionnaire on socio-economic, family and caregiving needs, along with the Instrument for Assessing Personal Social Networks. Results. Nearly one third a family caregivers experienced moderate caregiving burden, while more than half experienced high or very high levels of caregiving burden; financial support was perceived as the most needed form of support in the present, but residential home care was identified as the most needed form of support in the future; while more than a half considered home-based support and residential support viable options for their disabled family members with special care needs. These family caregivers reported "uncertainty" and "hope" as the most common feelings towards their family life in the future. On the topic of social networks, family relations were found to be crucial at the structural level; in terms of functional characteristics of the network, elevated scores were observed for reciprocity of support and satisfaction with the social network. Implications. This study highlights the importance of increasing the specificity of the assessments of needs for support in family caregivers of disabled adults with special care needs. The systematic conduction of these assessments may assist evidence-based decision making in social work interventions, such as for planning and managing social services, acknowledging and activating the families' own resources, and ultimately promote the efficacy and effectiveness 57 interventions aimed at improving the well-being of disabled citizens and their families.
Resumo:
Ao pensar na morte há um reconhecimento da vulnerabilidade humana e da própria fragilidade da vida. A morte é universal, mas experienciada de uma forma individualizada por cada um de nós, a partir da personalidade, experiências de vida, variáveis pessoais, idade, sexo, religião. Vivenciar a morte e o morrer poderá conduzir a sensações de medo e ansiedade. Os agentes funerários que lidam diariamente com a morte e com o “luto” (do corpo morto e dos familiares em relação ao ente querido que perderam) poderão estar expostos a sentimentos de ansiedade depressiva pela ativação diária do confronto com a própria morte, ou com a morte de pessoas a quem estão intimamente ligados. É objetivo deste estudo avaliar os níveis de ansiedade em face da morte em agentes funerários, e ainda explorar a eventual associação entre fatores sociodemográficos e profissionais selecionados e esta variável. A amostra é composta por 60 sujeitos de uma empresa funerária em Portugal. Os instrumentos psicométricos utilizados foram a Escala de Ansiedade face à Morte (DAQ), e um questionário sociodemográfico desenhado para o presente estudo. Os resultados globais mostram que os Agentes Funerários apresentam níveis de ansiedade face à morte estatisticamente significativos (M = 35,88; DP = 9,02). O género, a idade, religião, anos de experiência, estado civil, terem filhos, ter morrido alguém próximo ou significativo, especificidade de trabalho: ser comercial ou operacional o número de contatos, não marcam significativamente a forma como os sujeitos em estudo percecionam a sua ansiedade em face da morte. Os níveis de ansiedade aumentam entre aqueles que não tiveram formação específica para lidar com estas situações. / When thinking about death there is recognition of human vulnerability and fragility of life itself. Death is universal but experienced individually by each of us, through personality, life experiences, personal variables, age, sex, religion. Experiencing death and dying can lead to feelings of fear and anxiety. Funeral Agents who daily deal with death and with the "mourning" (the dead body and the family of the deceased) may be exposed to feelings of depressive anxiety activated by the daily confrontation with death itself or death of people who are close to them. The aim of this study is to assess the levels of anxiety in Funeral Agents when facing death, and also explore the eventual association of social-demographic and professional factors with this variable. The sample consisted of 60 subjects of a Portuguese Funeral company. The instruments used were the Death Anxiety Questionnaire (DAQ) and a socialdemographic questionnaire designed for the present study. The overall results show that Funeral Agents present anxiety levels statistically significant when facing death (M = 35.88, SD = 9.02). Gender, age, religion, years of experience, marital status, having children, the death of someone close or important, and the specificity of the job (commercial or operational agent), the number of contacts, show no statistically significant association with anxiety when facing death. However, the levels of anxiety increase among those who had had no specific formation to deal with these situations.
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Microglial cells are the resident immune cells of central nervous system (CNS) and the major players in neuroinflammation. These cells are also responsible for surveilling the neuronal microenvironment, and upon injury to the CNS they change their morphology and molecular profile and become activated. Activated status is associated with microglia proliferation, migration to injury foci, increased phagocytic capacity, production and release of reactive oxygen species (ROS), cytokines (pro- or anti-inflammatory) and reactive nitrogen species. Microglia activation is crucial for tissue repair in the healthy brain. However, their chronic activation or deregulation might contribute for the pathophysiology of neurodegenerative diseases. A better understanding of the mechanisms underlying microglial cell activation is important for defining targets and develop appropriate therapeutic strategies to control the chronic activation of microglia. It has been observed an increase in profilin (Pfn) mRNA in microglial cells in the rat hippocampus after unilateral ablation of its major extrinsic input, the entorhinal cortex. This observation suggested that Pfn might be involved in microglia activation. Pfn1 is an actin binding protein that controls assembly and disassembly of actin filaments and is important for several cellular processes, including, motility, cell proliferation and survival. Here, we studied the role of Pfn1 in microglial cell function. For that, we used primary cortical microglial cell cultures and microglial cell lines in which we knocked down Pfn1 expression and assessed the activation status of microglia, based on classical activation markers, such as: phagocytosis, glutamate release, reactive oxygen species (ROS), pro- and anti-inflammatory cytokines. We demonstrated that Pfn1 (i) is more active in hypoxia-challenged microglia, (ii) modulates microglia pro- and anti-inflammatory signatures and (iii) plays a critical role in ROS generation in microglia. Altogether, we conclude that Pfn1 is a key protein for microglia homeostasis, playing an essential role in their activation, regardless the polarization into a pro or anti-inflammatory signature.