980 resultados para Mononuclear
Resumo:
Virgin olive oil (VOO) is considered to be one of the main components responsible for the health benefits of the Mediterranean diet, particularly against atherosclerosis where peripheral blood mononuclear cells (PBMNCs) play a crucial role in atherosclerosis development and progression. The objective of this article was to identify the PBMNC genes that respond to VOO consumption in order to ascertain the molecular mechanisms underlying the beneficial action of VOO in the prevention of atherosclerosis. Gene expression profiles of PBMNCs from healthy individuals were examined in pooled RNA samples by microarrays after 3 weeks of moderate and regular consumption of VOO, as the main fat source in a diet controlled for antioxidant content. Gene expression was verified by qPCR. The response to VOO consumption was confirmed for individual samples (n = 10) by qPCR for 10 upregulated genes (ADAM17, ALDH1A1, BIRC1, ERCC5, LIAS, OGT, PPARBP, TNFSF10, USP48, and XRCC5). Their putative role in the molecular mechanisms involved in atherosclerosis development and progression is discussed, focusing on a possible relation with VOO consumption. Our data support the hypothesis that 3 weeks of nutritional intervention with VOO supplementation, at doses common in the Mediterranean diet, can alter the expression of genes related to atherosclerosis development and progression.
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Radioiodinated recombinant human interferon-gamma (IFN gamma) bound to human monocytes, U937, and HL60 cells in a specific, saturable, and reversible manner. At 4 degrees C, the different cell types bound 3,000-7,000 molecules of IFN gamma, and binding was of comparable affinity (Ka = 4-12 X 10(8) M-1). No change in the receptor was observed after monocytes differentiated to macrophages or when the cell lines were pharmacologically induced to differentiate. The functional relevance of the receptor was validated by the demonstration that receptor occupancy correlated with induction of Fc receptors on U937. Binding studies using U937 permeabilized with digitonin showed that only 46% of the total receptor pool was expressed at the cell surface. The receptor appears to be a protein, since treatment of U937 with trypsin or pronase reduced 125I-IFN gamma binding by 87 and 95%, respectively. At 37 degrees C, ligand was internalized, since 32% of the cell-associated IFN gamma became resistant to trypsin stripping. Monocytes degraded 125I-IFN gamma into trichloroacetic acid-soluble counts at 37 degrees C but not at 4 degrees C, at an approximate rate of 5,000 molecules/cell per h. The receptor was partially characterized by SDS-polyacrylamide gel electrophoresis analysis of purified U937 membranes that had been incubated with 125I-IFN gamma. After cross-linking, the receptor-ligand complex migrated as a broad band that displayed an Mr of 104,000 +/- 18,000 at the top and 84,000 +/- 6,000 at the bottom. These results thereby define and partially characterize the IFN gamma receptor of human mononuclear phagocytes.
Resumo:
Colorectal cancer (CRC) is the second leading cause of cancer-related death in developed countries. Early detection of CRC leads to decreased CRC mortality. A blood-based CRC screening test is highly desirable due to limited invasiveness and high acceptance rate among patients compared to currently used fecal occult blood testing and colonoscopy. Here we describe the discovery and validation of a 29-gene panel in peripheral blood mononuclear cells (PBMC) for the detection of CRC and adenomatous polyps (AP). Blood samples were prospectively collected from a multicenter, case-control clinical study. First, we profiled 93 samples with 667 candidate and 3 reference genes by high throughput real-time PCR (OpenArray system). After analysis, 160 genes were retained and tested again on 51 additional samples. Low expressed and unstable genes were discarded resulting in a final dataset of 144 samples profiled with 140 genes. To define which genes, alone or in combinations had the highest potential to discriminate AP and/or CRC from controls, data were analyzed by a combination of univariate and multivariate methods. A list of 29 potentially discriminant genes was compiled and evaluated for its predictive accuracy by penalized logistic regression and bootstrap. This method discriminated AP >1cm and CRC from controls with a sensitivity of 59% and 75%, respectively, with 91% specificity. The behavior of the 29-gene panel was validated with a LightCycler 480 real-time PCR platform, commonly adopted by clinical laboratories. In this work we identified a 29-gene panel expressed in PBMC that can be used for developing a novel minimally-invasive test for accurate detection of AP and CRC using a standard real-time PCR platform.
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The use of probes, such as paramagnetic species diluted in diamagnetic materials in EPR spectroscopy, and mathematical tools such, as the Kubelka-Munk function in DRUV-VIS spectroscopy are strategies in the analysis of complex mixtures of solid materials. The results obtained here show that the solid state reaction between the complex, [VO(acac)(BMIMAPY)] [ClO4], BMIMAPY = [(bis(1-methylimidazole-2-yl)methyl)(2-(pyridyl-2-yl)ethyl) amine] and acac = acetilacetonate, with kaolinite turns possible to obtain anisotropic EPR spectrum of the complex with a reasonable level of resolution. The study by DRUV-VIS using the method of second derivative mode of the Kubelka-Munk function revealed new complex structural arrangements, a solid hitherto unknown.
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Flavonoids are one of the most important compound groups applied as medicine given their antioxidant properties, but several intrinsic properties can be improved through structural modifications to their molecules. Here, the synthesis and characterization of a new gallium (III) complex with quercetin is described. Electrochemical properties, as well as antioxidant and cytotoxic activities, were investigated and compared to the free flavonoid molecule. The mononuclear complex obtained, [Ga(C15H9O7)3].2H2O.2CH3OH.CH3CH2OH, seems more active as a DPPH radical scavenger given its lower oxidation potential compared to quercetin. The new complex cytotoxic responses have shown to be more effective than those of the free flavonoid and of lapachol used as a control.
Resumo:
OBJETIVOS: Para se evitar o estado asplênico, muitas medidas preservadoras do baço têm sido propostas na literatura, como a esplenorrafia, a esplenectomia parcial com preservação dos vasos hilares e o auto-implante de tecido esplênico. A esplenectomia subtotal, com conservação do pólo superior do baço, nutrido apenas pelos vasos esplenogástricos é uma alternativa quando o pedículo esplênico precisa ser ligado. O objetivo deste estudo foi avaliar a influência das esplenectomias parcial, subtotal e total na distribuição da Escherichia coli no sistema mononuclear fagocitário. MÉTODO: Foram estudados 32 ratos divididos em 4 grupos: operação simulada (mantendo todo o baço), esplenectomia parcial, esplenectomia subtotal e esplenectomia total. Após cinco semanas da operação, uma alíquota de Escherichia coli marcada com 99m-tecnécio foi injetada por via venosa. Após 20 minutos, os animais foram mortos, e o baço, os pulmões e o fígado foram retirados para se verificar a distribuição das bactérias marcadas. RESULTADOS: A quantidade de Escherichia coli no tecido esplênico foi maior no grupo com o baço íntegro em comparação com os grupos esplenectomia parcial e subtotal. A distribuição da bactéria marcada pelo baço não diferiu nos grupos com esplenectomia parcial ou subtotal. A quantidade de bactérias no pulmão foi maior no grupo esplenectomia parcial do que a do grupo com esplenectomia subtotal. Após esplenectomia subtotal, a distribuição da bactéria marcada foi maior no fígado em comparação com a captação desse órgão nos demais grupos. CONCLUSÕES: O pólo superior do baço, suprido apenas pelos vasos esplenogástricos, tem capacidade de remover da circulação bactérias vivas, mostrando que, mesmo sem a vascularização pelo pedículo esplênico, há uma eficiente depuração sangüínea. A distribuição da Escherichia coli pelo sistema mononuclear fagocitário apresenta comportamentos diferentes, dependendo do tipo de esplenectomia a que o animal é submetido.
Resumo:
OBJETIVO: O auto-implante esplênico parece constituir a única alternativa para preservação de tecido esplênico, após esplenectomia total. O objetivo deste trabalho foi analisar a depuração de Escherichia coli pelos órgãos do sistema mononuclear fagocitário (SMF) após esplenectomia total e auto-implante esplênico. MÉTODO: Utilizou-se um modelo experimental com ratos Wistar jovens e adultos, de ambos os sexos, submetidos a esplenectomia total e auto-implante esplênico. O método de avaliação foi a inoculação intravenosa de suspensão de Escherichia coli marcada com tecnécio - 99m. Analisou-se a captação desta bactéria pelos órgãos do SMF e o remanescente bacteriano na corrente sangüínea. RESULTADOS: Dentro de cada grupo, não foi encontrado diferença entre animais jovens e adultos no que se refere à captação de bactérias pelos órgãos do SMF. Na comparação entre os grupos verificou-se que o percentual médio de captação pelo baço e pelo fígado de animais do Grupo-Controle foi maior que o dos auto-implantes. Embora a captação de bactérias pelo baço de animais do Grupo-Controle tenha sido maior que o dos auto-implantes esplênicos, o remanescente bacteriano no sangue não foi diferente. Animais submetidos a esplenectomia total isolada apresentam maior remanescente de bactérias na corrente sangüínea que animais do Grupo-Controle ou do grupo submetido a esplenectomia total combinada com auto-implante esplênico. CONCLUSÃO: Nossos resultados indicam que o auto-implante esplênico é eficaz na depuração de bactérias, em rato, mediante a fagocitose por seus macrófagos, e não interfere na função de remoção bacteriana do fígado e do pulmão.
Resumo:
Cinco cavalos adultos foram submetidos à coleta de medula óssea do esterno e de tecido adiposo da região glútea. As amostras foram processadas para obtenção da fração mononuclear da medula óssea e fração vascular estromal do tecido adiposo, o número de células obtidas e a viabilidade celular foram determinados. Em seguida, realizou-se o congelamento das amostras em solução contendo 20% de soro fetal bovino e 10% de dimetilsulfóxido. Depois de um mês, realizou-se o descongelamento das amostras e a viabilidade celular foi novamente mensurada. Os resultados revelaram que as técnicas utilizadas tanto para coleta de medula óssea quanto de tecido adiposo em equinos são simples, rápidas e seguras. As metodologias adotadas para o processamento das amostras foram eficientes, obtendo-se aproximadamente 95% de viabilidade celular. Após o descongelamento, a viabilidade média das amostras de células mononucleares da medula óssea foi de 86% e da fração vascular estromal do tecido adiposo de 64%. Frente à importância da terapia celular na clínica médica de equinos, concluiu-se que é necessária a realização de mais estudos, visando padronizar uma técnica de criopreservação que mantenha a integridade das células da fração mononuclear da medula óssea e da fração vascular estromal do tecido adiposo de equinos.
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The objective of this study was to evaluate the culture of equine bone marrow mononuclear fraction and adipose tissue - derived stromal vascular fraction cells in two different cell culture media. Five adult horses were submitted to bone marrow aspiration from the sternum, and then from the adipose tissue of the gluteal region near the base of the tail. Mononuclear fraction and stromal vascular fraction were isolated from the samples and cultivated in DMEM medium supplemented with 10% fetal bovine serum or in AIM-V medium. The cultures were observed once a week with an inverted microscope, to perform a qualitative analysis of the morphology of the cells as well as the general appearance of the cell culture. Colony-forming units (CFU) were counted on days 5, 15 and 25 of cell culture. During the first week of culture, differences were observed between the samples from the same source maintained in different culture media. The number of colonies was significantly higher in samples of bone marrow in relation to samples of adipose tissue.
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Abstract: Chlorocebus aethiops is a species of non-human primate frequently used in biomedical research. Some research involves this species as an experimental model for various diseases and possible treatment with stem cells. The bone marrow is one of the main sources of these cells and provides easy access. The aim of this study was to standardize the protocol of collection and separation of bone marrow in C. aethiops. Ten animals were submitted to puncture of bone marrow with access to the iliac crest and cell separation by density gradient. The bone marrow of C. aethiops had an average of 97% viability. From the results achieved, we can conclude that C. aethiops is an excellent model to obtain and isolate mononuclear cells from bone marrow, fostering several studies in the field of cell therapy.
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Nitric oxide (NO) is an extremely important and versatile messenger in biological systems. It has been identified as a cytotoxic factor in the immune system, presenting anti- or pro-inflammatory properties under different circumstances. In murine monocytes and macrophages, stimuli by cytokines or lipopolysaccharide (LPS) are necessary for inducing the immunologic isoform of the enzyme responsible for the high-output production of NO, nitric oxide synthase (iNOS). With respect to human cells, however, LPS seems not to stimulate NO production in the same way. Addressing this issue, we demonstrate here that peripheral blood mononuclear cells (PBMC) obtained from schistosomiasis-infected patients and cultivated with parasite antigens in the in vitro granuloma (IVG) reaction produced more nitrite in the absence of LPS. Thus, LPS-induced nitrite levels are easily detectable, although lower than those detected only with antigenic stimulation. Concomitant addition of LPS and L-N-arginine methyl ester (L-NAME) restored the ability to produce detectable levels of nitrite, which had been lost with L-NAME treatment. In addition, LPS caused a mild decrease of the IVG reaction and its association with L-NAME was responsible for reversal of the L-NAME-exacerbating effect on the IVG reaction. These results show that LPS alone is not as good an NO inducer in human cells as it is in rodent cells or cell lines. Moreover, they provide evidence for interactions between LPS and NO inhibitors that require further investigation.
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Several studies show the ability of macrophages to remove particles injected into the bloodstream. This function seems to be increased in the presence of acute renal failure. The objective of the present study was to assess the phagocytic function of the main organs (spleen, liver and lung) of the mononuclear phagocytic system in renal and postrenal failures. Fifteen rats (250-350 g) were divided into three groups (N = 5): group I - control; group II - ligature of both ureters, and group III - bilateral nephrectomy. On the third postoperative day, all animals received an iv injection of 1 ml/kg 99mTc sulfur colloid. Blood samples were collected for the assessment of plasma urea, creatinine, sodium, and potassium concentrations and arterial gasometry. Samples of liver, spleen, lung and blood clots were obtained and radioactivity was measured. Samples of liver, spleen, lung and kidney were prepared for routine histopathological analysis. Plasma urea, creatinine and potassium concentrations in groups II and III were higher than in group I (P<0.05). Plasma sodium concentrations in groups II and III were lower than in group I (P<0.05). Compensated metabolic acidosis was observed in the presence of postrenal failure. Group II animals showed a lower level of radioactivity in the spleen (0.98) and lung (2.63), and a higher level in the liver (105.51) than control. Group III animals showed a lower level of radioactivity in the spleen (11.94) and a higher level in the liver (61.80), lung (11.30) and blood clot (5.13) than control. In groups II and III liver steatosis and bronchopneumonia were observed. Renal and postrenal failures seem to interfere with blood clearance by the mononuclear phagocytic system.
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Evaluation of HIV-induced IL-2 production by peripheral blood mononuclear cells (PBMC) and HIV-specific T helper and cytotoxic T lymphocyte (CTL) responses in health care workers (HCW) occupationally exposed to HIV reveals a high rate of response to HIV among non-seroconverters. IL-10 is also known to interfere with HIV infection in vitro. To evaluate the induction of IL-10 by HIV antigens in HCW occupationally exposed to HIV, 18 HCW with percutaneous injury were enrolled in this study, 9 of them exposed to HIV-contaminated blood, and 9 exposed to HIV-negative blood. PBMC were incubated on plates coated with HIV-1 antigens, and IL-10 was measured in supernatants by ELISA. Five of nine HCW exposed to HIV-contaminated blood presented HIV-induced IL-10. Two of nine HCW exposed to HIV-negative source patients also had detectable levels of HIV-induced IL-10, one of them in the sample obtained on the day of accidental exposure. There was a relationship between the type of device involved in injury and IL-10 production. Individuals exposed to hollow needles or scalpels presented HIV-induced IL-10, whereas those exposed to solid needles and to digital puncture did not, suggesting a relationship between infectious load and IL-10. Although occupational exposure to HIV leads to a low rate of seroconversion, these individuals can develop an antigen-specific immune response characterized in our study by induction of IL-10 in PBMC in vitro.
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As a consequence of the proinflammatory environment occurring in dialytic patients, cytokine overproduction has been implicated in hemodialysis co-morbidity. However, there are discrepancies among the various studies that have analyzed TNF-alpha synthesis and the presence of peripheral blood mononuclear cell (PBMC) priming in this clinical setting. We measured bioactive cytokine by the L929 cell bioassay, and evaluated PBMC TNF-alpha production by 32 hemodialysis patients (HP) and 51 controls. No difference in TNF-alpha secretion was observed between controls and HP (859 ± 141 vs 697 ± 130 U/10(6) cells). Lipopolysaccharide (5 µg/ml) did not induce any further TNF-alpha release, showing no PBMC priming. Paraformaldehyde-fixed HP PBMC were not cytotoxic to L929 cells, suggesting the absence of membrane-anchored TNF-alpha. Cycloheximide inhibited PBMC cytotoxicity in HP and controls, indicating lack of a PBMC TNF-alpha pool, and dependence on de novo cytokine synthesis. Actinomycin D reduced TNF-alpha production in HP, but had no effect on controls. Therefore, our data imply that TNF-alpha production is an intrinsic activity of normal PBMC and is not altered in HP. Moreover, TNF-alpha is a product of de novo synthesis by PBMC and is not constitutively expressed on HP cell membranes. The effect of actinomycin D suggests a putative tighter control of TNF-alpha mRNA turnover in HP. This increased dependence on TNF-alpha RNA transcription in HP may reflect an adaptive response to hemodialysis stimuli.
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Interferon (IFN)-alpha receptor mRNA expression in liver of patients with chronic hepatitis C has been shown to be a response to IFN-alpha therapy. The objective of the present study was to determine whether the expression of mRNA for subunit 1 of the IFN-alpha receptor (IFNAR1) in peripheral blood mononuclear cells (PBMC) is associated with the response to IFN-alpha in patients with chronic hepatitis C. Thirty patients with positive anti-HCV and HCV-RNA, and abnormal levels of alanine aminotransferase in serum were selected and treated with IFN-alpha2b for one year. Those with HBV or HIV infection, or using alcohol were not included. Thirteen discontinued the treatment and were not evaluated. The IFN-alpha response was monitored on the basis of alanine aminotransferase level and positivity for HCV-RNA in serum. IFNAR1-mRNA expression in PBMC was measured by reverse transcription-polymerase chain reaction before and during the first three months of therapy. The results are reported as IFNAR1-mRNA/ß-actin-mRNA ratio (mean ± SD). Before treatment, responder patients had significantly higher IFNAR1-mRNA expression in PBMC (0.67 ± 0.15; N = 5; P < 0.05) compared to non-responders (0.35 ± 0.17; N = 12) and controls (0.30 ± 0.16; N = 9). Moreover, IFNAR1-mRNA levels were significantly reduced after 3 months of treatment in responders, whereas there were no differences in IFNAR1 expression in non-responders during IFN-alpha therapy. Basal IFNAR1-mRNA expression was not correlated with the serum level of alanine and aspartate aminotransferases or the presence of cirrhosis. The present results suggest that IFNAR1-mRNA expression in PBMC is associated with IFN-alpha response to hepatitis C and may be useful for monitoring therapy in patients with chronic hepatitis C.