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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Formação de oxigênio singlete O2 (1Δg) por fagócitos / Singlet oxygen formation O2 (1Δg) by phagocytes

Flavia Garcia 20 October 2005 (has links)
Neste trabalho avaliamos a formação de oxigênio singlete in vitro em fagócitos, (células mononucleares e neutrófilos) isolados de sangue periférico humano, e eosinófilos, de lavado bronco alveolar de camundongos balb/c, ativados por estímulo partículado: zimosan opsonizado contendo o 9,10difenilantraceno (DPA) adsorvido como sonda captadora de 1O2. Por este método, a formação do 1O2 pode ser verificada pela formação do 9,10-difenilantraceno endoperóxido (DPAO2), que é detectado por HPLC. Observamos, que os fagócitos formam 1O2 e que esta formação parece ocorrer de forma diferenciada para os dois tipos celulares (neutrófilos e células mononucleares). Visando ampliar os estudos anteriores sobre o papel da melatonina (MLT) no processo inflamatório, foi testado seu efeito em fagócitos e a relação na produção de 1O2 destas células. Observamos que MLT inibe a formação de 1O2 totalmente no caso de neutrófilos e parcialmente no caso de células mononucleares e eosinófilos. Paralelamente, foi desenvolvida a síntese de um novo captador químico de 1O2, o éster 9,10-antracenil-3-bispropionato de etila (ABPE), cuja finalidade principal é o acúmulo no interior da célula, depois de sofrer hidrólise enzimática. Esta sonda, terá facil acesso ao interior das células em sua forma ester. Este novo captador de 1O2 foi testado em células mononucleares e neutrófilos estimulados de formas diferentes: via receptor independente e dependente. Os resultados demonstraram produção equivalente de 1O2 nestes fagócitos. / In this study, we evaluated the singlet oxygen (1O2) formation in vitro from phagocytes (neutrophils and mononuclear cells) isolated from human blood cells and eosinophils isolated from bronchoalveolar lavage fluid of mice balb/c activated, by opsonized zymosan. To determine whether singlet oxygen is produced by phagocytes, zymosan particles were coated with a specific chemical trap for 1O2, 9,10-diphenylanthracene (DPA). The production of 1O2 was followed using HPLC, to measure its product, 9,10-diphenylanthracene endoperoxide (DPAO2). We also noticed that the 1O2 production occurs at different levels of for two cell types, neutrophils and mononuclear cells. In order to broaden previous studies on the role of melatonin (MLT) in inflammatory processes, its effect was tested in phagocytes was tested in relation to 1O2 formation by these cells. We observed that MLT inhibits the 1O2 formation totallymt neutrophils and partiallym mononuclear cells and eosinophils. At the some time, it was also developed the synthesis of a new probe for 1O2, the 9,10-anthracene-bis-3-ethyl-propionate (ABEP), with the purpose to accumulate inside the cells, after its enzymatic hydrolysis. This probe presents easy acess to the inferior of the cells in its ester form. This new probe for trapping 1O2 was tested in mononuclear cells and neutrophils stimulated in two ways: via independent and dependent receptor. The results showed equivalent production of 1O2 for both cell types.
102

Caracterização do perfil de compostos orgânicos voláteis produzidos por cultura de células e animais infectados com Leishmania infantum / Characterization of the profile of volatile organic compounds produced by cell cultures and animals infected with Leishmania infantum

Naira Ferreira Anchieta 19 December 2016 (has links)
Alguns parasitas modificam o perfil de Compostos Orgânicos Voláteis (COVs) de seus hospedeiros na tentativa de atrais/dispersar seus vetores, assegurando a propagação do parasita e a manutenção do ciclo da doença. É sabido que o mosquito Lutzomyia longipalpis, vetor da Leishmaniose Visceral (LV) são mais atraídos por cães infectados que não infectados. Este trabalho tem como objetivo identificar e caracterizar os Compostos Orgânicos Voláteis emitidos por culturas de células e hamsters infectados Mesocricetus auratus com Leishmania infantum (MHOM/74/PP75). Células aderentes mononucleares de baço de hamsters foram separadas com Ficoll e distribuídas em placas de 24 poços com 2x106 células por poço. Após 42 horas, as células foram infectadas e os COVs foram coletados por \"headspace\" por 18 horas. Os COVs foram determinados por comparação com as placas controle: controle células aderentes mononucleares, controle L. infantum, e controle meio RPMI 1640.40 Hamsters foram subdivididos em 2 grupos: 20 animais foram infectados com formas promastigotas metacíclicas de L. infantum selecionadas com aglutinina de amendoim (PNA) por via intracardíaca com 1x107 parasitas. Os animais foram acompanhados por 4 meses pós infecção e as amostras foram coletadas colocando os animais em sacos de poliéster conectados com um tubo de metal recheado com Tenax TA acoplado a uma bomba de sucção automática por 10 minutos. Todas as amostras foram analisadas por dessorção térmica via Cromatografia gasosa/ Espectrometria de Massas (CG-EM). Nas culturas de células, 2 compostos estão presentes apenas nas culturas infectadas: 1,2-difenilciclobutano e (E)-(2,3-Difenil Ciclopropil)-metil-fenilsulfóxido. O 2,4-dimetilbenzaldeído estava presente na placa controle contendo meio RPMI 1640. Por outro lado, em ambas as placas infectadas e controle com células aderentes mononucleares, o 3-metileno-heptano estava presente. Outros compostos contendo os grupos químicos aldeídos ou álcoois ou hidrocarbonetos aromáticos foram detectados em todas as placas, mas com diferentes áreas de pico (quantidade). Quando comparamos os COVs emitidos por hamsters infectados e controles, nenhuma diferença foi encontrada. Os compostos emitidos por culturas de células infectadas mostram que a infecção com L.infantum é capaz de modificar o perfil de COVs em culturas de células. Outros compostos encontrados em todas as placas, mas com diferentes áreas de pico podem indicar que a infecção aumenta a liberação de algumas substâncias que são possíveis atrativos para vetores. / Some parasites can modify their hosts Volatile Organic Compounds (VOCs) profile in order to attract / disperse their vectors, ensuring spreading of the parasite and maintenance of the disease cycle. It is already known that Lutzomyia longipalpis sandflies, the vectors of Visceral Leishmaniasis (VL), are more attracted to infected than to non-infected dogs. This work aims to identify and characterize the VOCs emitted by cell cultures and hamsters Mesocricetus auratus infected with Leishmania infantum (MHOM/74/PP75). Spleen adherent mononuclear cells of hamsters were separed with Ficoll and distributed in flat-bottomed 24-well plates at 2x106 cells per well. After 42 hours, the cells were infected and VOCs were collected from the \"headspace\" for 18 hours. The VOCs were determined in comparison with the controls plates: control mononuclear adherent cells, control L. infantum and control medium RPMI 1640. 40 Hamsters were subdivided in two groups: 20 animals were used as a control group and 20 animals were infected with metaciclic form of L. infantum selected by peanut agglutinin (PNA) by intracardiac route with 1x107 parasites. The animals were followed up for 4 months post-infection and the samples were collected by introducing the hamsters in a polyester bag connected with a metal tube filled with the Tenax TA adsorbent coupled to an automatic suction pump for 10 minutes. All samples were analyzed by thermal desorption via Gas Chromatography/Mass Spectrometry (GCMS). In cell cultures, two compounds were present only in infected cultures: 1, 2- diphenyl cyclobutane, and trans-[(2, 3-Diphenylcyclopropyl) methyl] phenyl sulfoxide. 2, 4-dimethyl benzaldehyde was present in the control well containing RPMI 1640 medium. On the other hand, in both infected and control wells with mononuclear adherent cells, 3-methylene heptane was present. Other compounds containing either aldehydes or alcohols or aromatic hydrocarbon chemical groups were detected in all plates, but with different peak areas (i.e., amounts). When comparing the VOCs emitted by infected and control hamsters, no difference was found. The compounds emitted only by infected cell cultures show that the infection with L. infantum is able to modify the profile of VOCs in cell cultures. The other compounds found in all plates but with different peak areas may indicate that infection may increase the release of some substances that are possible attractants for vectors.
103

Estudo molecular da via extrínseca da apoptose em indivíduos com imunodeficiência comum variável. / Molecular study of extrinsec apoptosis pathway in patients with Common Variable Immunodeficiency.

Lilian Cristina Buzzetto 24 May 2012 (has links)
A Imunodeficiência de Variável Comum (ICV) é caracterizada por baixos níveis de imunoglobulinas com susceptibilidade a. Analisamos a distribuição de linfócitos, apoptose espontânea e a expressão gênica de receptores de morte, ligantes, adaptadores, moléculas reguladoras, inibidoras e anti-apotóticas em células CD4+ e CD8+ de 19 pacientes ICV e 19 controles. Pacientes com ICV apresentam diminuição na frequência de linfócitos TCD4+ e CD4+CD45RA+ e menor relação CD4/CD8 que indivíduos saudáveis. O grupo de pacientes mostrou maior frequência de apoptose espontânea em linfócitos totais e CD4+. Células CD4+ dos indivíduos afetados apresentaram menor expressão gênica de TRAIL-R, BCL-2, FLIPL e FADD; células CD8+ apresentaram diminuição da expressão gênica de TRAIL, FADD, BCL-2, BCL -xL e um aumento de FLIPs. Os resultados sugerem um desequilíbrio nos mecanismos que controlam a apoptose de linfócitos nestes pacientes, o que pode ajudar a elucidar as alterações observadas no compartimento de células T dos pacientes com ICV. / Common Variable Immunodeficiency (CVID) is is characterized by low immunoglobulins levels with susceptibility to infections. We have analyzed T cell distribution and spontaneous apoptosis in peripheral blood of CVID, as well as gene expression of several molecules involved in apoptosis, including death receptors, ligands, adapters, regulatory and anti-apototic molecules in CD4+ and CD8+ cells of 19 CVID patients and 19 healthy subjects. CVID subjects present decreased frequency of TCD4+ and CD4+ CD45RA+ cells and lower CD4/CD8 ratio than healthy controls. CVID group also presented higher frequency of spontaneous apoptosis in lymphocytes and CD4+ cells. CD4+ showed lower expression of TRAIL-R, BCL-2, FLIPL and FADD; CD8+ cells presented lower expression of TRAIL, FADD, BCL-2, BCL-xL and a augment of FLIP. Results suggest an imbalance in mechanisms controlling cell death of those patients lymphocytes, which might help to elucidate the changes observed in T cell compartment of CVID patients.
104

Amilóide sérica A: efeitos biológicos sobre células mononucleares / Serum amyloid A: biological effects on mononuclear cells

Silvana Sandri 04 August 2008 (has links)
Nos últimos anos, nosso grupo de pesquisa vem descrevendo vários efeitos da SAA em células do sistema imune no que diz respeito à expressão e liberação de citocinas pró-inflamatórias. Neste estudo centramos nossa atenção na verificação dos efeitos da SAA sobre células mononucleares. Para isto, usamos três modelos experimentais. Em murinos, descrevemos a habilidade da SAA induzir a produção de NO por macrófagos peritoneais e, com uso de animais knockout para TLR4, sugerimos que SAA seja um ligante endógeno do TLR4. Em células mononucleares de sangue periférico humano, a SAA induz a expressão e liberação de CCL20, uma quimiocina importante na transição da resposta imune inata para adaptativa, bem como a expressão dos fatores M-CSF e VEGF. Em células THP-1, mostramos a cinética de fosforilação de proteínas tirosina quinases promovida pela SAA e comparamos com LPS, um estímulo pró-inflamatório clássico. Ainda em células THP-1 mostramos que a SAA induz a fosforilação de duas proteínas importantes no processo inflamatório por induzirem a ativação de NFκB; a p38 e a ERK1/2. Com este estudo contribuímos com o conhecimento a respeito do papel regulatório da SAA em células mononucleares. A ação da SAA sobre estas células torna-se importante, pois estas são cruciais na resposta imune inata e também atuam como células acessórias na resposta imune adaptativa. Desta forma, evidencia-se que, no processo de fase aguda, a expressão e a síntese de SAA resultam na modulação de etapas que controlam este processo e sua progressão. / In the past few years, our research group has described various effects of serum amyloid A (SAA) on cells of the immune system regarding the expression and release of pro-inflammatory cytokines. In this study we have focused on the effects of SAA on mononuclear cells. In order to do this, we have used three experimental models. In the murine experimental model, we described SAA\'s ability to induce the production of NO through peritoneal macrophages and, by using knockout animals for TLR4, we suggested that SAA is an endogenous agonist of TLR4. In mononuclear cells of peripheral human blood, SAA induced the expression and release of CCL20, an important chemokine in the transition from the innate to the adaptive immune response, as well as the expression of M-CSF and VEGF-factors. In THP-1 cells, we showed the phosporylation kinetics of tyrosine protein kinases induced by SAA, and we compared it to LPS, a classic pro-inflammatory stimulus. We also demonstrated, in THP-1 cells, that SAA induced the phosphorylation of two proteins, namely p38 and ERK1/2, that are crucial in the inflammatory process because they induce the activation of transcription factors. With this study, we contributed to the knowledge of the regulatory role of SAA in mononuclear cells. Activity of SAA on these cells is highly important, for they are crucial in the innate immune response and act as accessory cells in the adaptive immune response. Hence it is evident that, in the acute phase process, the expression and synthesis of SAA result in the modulation of the phases that control this process and its progression.
105

Terapêutica experimental com células mononucleares da medula óssea em modelo animal de enfisema pulmonar. / Experimental therapy with bone marrow mononuclear cells in animal model of pulmonary emphysema.

Carolina Arruda de Faria 10 October 2011 (has links)
O enfisema pulmonar define-se como a destruição das paredes alveolares e consequente dispneia progressiva. Este trabalho objetivou a adequação de um modelo de transplante celular in vivo de BMMC em camundongos com enfisema pulmonar. O enfisema foi induzido por instilação nasal de elastase (4 UI por animal). O diâmetro alveolar médio para os grupos não tratados e tratados com elastase apresentou diferença estatisticamente significativa, e mudanças no padrão de expressão de metaloproteinases envolvidas no processo inflamatório foram detectadas, indicando que a instilação de uma dose de elastase promove lesão semelhante ao enfisema pulmonar. Infundiu-se 0,4ml de BMMC (7x106 céls./ml) nestes animais. No grupo tratado com células, detectou-se mudanças morfométricas e no padrão de expressão de metaloproteinases, indicando melhora na evolução da lesão pulmonar 21 dias após a infusão. Foram ainda avaliadas duas e três doses do pool de BMMC, porém os resultados das análises mostraram que não há diferenças entre estre grupos e os grupos controle. / Pulmonary emphysema is defined as the destruction of the alveolar walls and consequent progressive dyspnea. This study aimed the adequacy of a model of BMMC transplantation in vivo in mice with pulmonary emphysema. Emphysema was induced by nasal instillation of elastase (4 IU per animal). The mean linear intercept for the groups untreated and treated with elastase showed a statistically significant difference, and changes in the pattern of expression of metalloproteinases involved in inflammation were detected, indicating that the instillation of a dose of elastase promotes lung damage similar to emphysema. 0.4 ml of BMMC (7x106 céls. / ml) was infused in these animals. In the group treated with cells there were detected and morphometric changes in the pattern of expression of metalloproteinases, indicating an improvement in the evolution of lung injury 21 days after infusion. Were also evaluated two and three doses of the pool BMMC, but the results of the analysis showed no differences between experimental and the control groups.
106

Pesquisa de instabilidade gênica induzida por quimioterapia antineoplásica nas células mononucleares do sangue periférico de mulheres com câncer de mama / Systemic chemotherapy induces microsatellite instability in the peripheral blood mononuclear cells of breast cancer patients

Fernando Luiz Affonso Fonseca 17 June 2005 (has links)
O tratamento sistêmico é extremamente importante na abordagem clínica do câncer de mama. O presente estudo teve a finalidade de avaliar se a quimioterapia sistêmica é capaz de produzir instabilidade genética representada por instabilidade de microssatélites (MSI) e perda de heterozigosidade (LOH) na fração mononuclear do sangue periférico de pacientes portadoras de câncer de mama. Foram estudadas 119 amostras de sangue, obtidas seqüencialmente antes, durante e após a quimioterapia. Das 30 pacientes avaliadas, 27 apresentaram MSI em pelo menos uma das amostras estudadas e 6 desenvolveram LOH. Uma importante correlação foi obtida entre o número de eventos de MSI por amostra e quimioterápicos com agentes alquilantes (p < 0,0001). Entretanto, quando as amostras foram de pacientes em radioterapia, observou-se um menor número de eventos de MSI por amostra (p=0,038). Concluímos que o tratamento sistêmico pode induzir MSI e LOH em células mononucleares do sangue periférico de pacientes em tratamento quimioterápico com agentes alquilantes / Systemic chemotherapy is an important part of treatment for breast cancer. We conduced the present study to evaluate whether systemic chemotherapy could produce microsatellite instability (MSI) in the peripheral blood mononuclear cell fraction of breast cancer patients. We studied 119 sequential blood samples from 30 previously untreated breast cancer patients before, during and after chemotherapy. In 27 out of 30 patients we observed MSI in at least one sample, and six patients had loss of heterozygosity (LOH). We found a significant correlation between the number of MSI events per sample and chemotherapy with alkylating agents (p < 0.0001). However, when the samples were obtained in patients with radiotherapy we observed low MSI events per samples (p = 0.038). We concluded that systemic chemotherapy may induce MSI and LOH in peripheral blood mononuclear cells from breast cancer patients receiving alkylating agents
107

Odlišné vlastnosti buněk pupečníkové krve novorozenců zdravých a alergických matek / Different characteristics of cord blood cells of newborns of healthy and allergic mothers

Vlasáková, Kateřina January 2017 (has links)
The prevalence of allergy is increasing and it is becoming a serious problem not on- ly in medicine, but also in social and economic terms. The most effective way to minimize the development of allergic diseases is preventive measures. In recent years, many studies have attempted to confirm or rebut the hypothesis that early administration of probiotic bacteria to newborns and pregnant women before birth could have preventive effects on the development of allergy. In the Czech Republic, the probiotic strain Escherichia coli O83:K24:H31 (EC O83), being registered with the State Health Institute for Drug Control under the name Colinfant Newborn, has long been used to prevent allergies and paediatri- cians have long been known and used it against various diarrhoea. The aim of this work was to elucidate the effect of EC O83 on CBMC (cord blood mononuclear cells) and to compare the ability of CBMC of healthy mothers (children with a relatively low risk of developing allergic disease) and allergic mothers (children at high risk of developing allergies) to form cytokines in response to EC O83 stimulation. Phytohemagglutinin was used as a positive control, Escherichia coli Nissle 1917 was used as a reference probiotic strain, which is much more known abroad than EC O83. Cytokine production was detected by...
108

Co(II) Based Magnetic Systems. Part I Spin Crossover Systems and Dendritic Frameworks. Part II Co(II) Single Molecule Magnets.

Farghal, Ahmed M. S. January 2012 (has links)
This work comprises two main parts. The first part outlines our efforts to expand on the recent work of Gütlich et.al. by synthesizing Co(II) based spin crossover systems within a dendritic framework. We wanted to investigate the possibility of synthesizing different first generation, triazole containing dendrimers using “click” type reactions and their coordination ability with Co(II) ions. To this end we have had limited success mainly due to the numerous challenges in synthesizing a pure dendrimer product. The second part details our efforts in the synthesis of a mononuclear Co(II) based single molecule magnet. This comes as an extension to recent reports by Chang and Long where they have successfully obtained mononuclear Fe(II) single molecule magnets by inducing structural distortions within the complexes to amplify the spin-orbit coupling. We postulated that the use of Co(II) in conjunction with a bulky ligand framework would lead to desirable magnetic properties. We chose the known bis(imino)pyridine ligand scaffold due to its rich chemistry and its interesting and unexpected coordination behaviour, as we have seen in previous research efforts by our lab. To this end we were successful in isolating and characterizing 4 compounds, and we have carried out detailed magnetic measurements on the two most magnetically interesting species.
109

Terapeutická vaskulogeneze u pacientů s chronickou kritickou ischémií dolních končetin / Therapeutic vasculogenesis in patients with critical leg ischemia

Skalická, Lenka January 2011 (has links)
PhD Aims: The aim of our study was to evaluate an efficacy and safety of intra-arterial injection of bone marrow mononuclear cells (BMMCs) in patients with chronic critical limb ischemia (CLI) Methods.In average 400ml bone marrow blood was harvested from posterior iliac crests in 24 CLI patients. BMMCs were obtained from the blood by standard procedure used for bone marrow transplantation. After digital subtraction angiography was performed in each patient, BMMCs were injected into arteries of 28 limbs. Primary outcome was the efficacy of BMMCs injection measured as a successfull healing of limb defects, a change of Fontain ischemia grade and a rate of high limb amputations. Secondary outcomes were a safety of the BMMCs injections, changes in angiographic findings after BMMCs injections and changes in quality of life (questionnaire SF-36). Results: After one year follow-up all patients were alive and 2 patients have undergone high limb amputation. Out of 14 limb defects, eleven have been healed completely and the average Fontain ischemia grade has changed from baseline value of 3.5 to 2.0 after one year (P<0.0001). Angiographic findings have improved in all examined segments of limb vessels. One year after the procedure patients have reported significant improvement. Conclusion: The intra-arterial...
110

Exercise and Cardiovascular Disease

Smith, John K. 01 January 2010 (has links)
Cardiovascular disease is the main cause of death in the United States. Although it is recognized that moderate intensity long-term exercise can decrease the chances of dying from cardiovascular disease by favorably modifying risk factors such as hypertension, obesity, hyperlipidemia, and insulin resistance, physical activity also enhances longevity by mechanisms independent of these risk factors. This review briefly summarizes what is known about the inflammatory nature of atherosclerosis and how long-term aerobic exercise can reduce the atherogenic activity of endothelial cells, blood mononuclear cells, and adipose tissue.

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