212 resultados para NEUTROPHIL


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Os estudos das secreções traqueobrônquicas são amplamente utilizados nas pesquisas de doenças pulmonares nas diversas espécies animais, inclusive no homem. Os objetivos desta pesquisa foram a viabilização da técnica de colheita de lavado traqueobrônquico na espécie ovina e o estudo da relação clínico-citológica do lavado de ovinos portadores de broncopneumonia e sadios. Foram utilizados 33 ovinos, 18 sadios e 15 portadores de enfermidade respiratória com sinais clínicos de envolvimento das vias aéreas, divididos nos respectivos grupos, GS e GD. Após o exame físico foi realizado o lavado traqueobrônquico por via nasotraqueal. A colheita do lavado foi feita com a inoculação e aspiração de solução fisiológica estéril. As amostras foram processadas citologicamente através de citocentrifugação e coradas pelos métodos Wright-Giemsa e Shorr. Tanto a contagem total de células epiteliais quanto o número de hemácias por mililitro foi maior no grupo de animais com broncopneumonia. Nos animais sadios notou-se predomínio de macrófagos, seguido por células epiteliais cilíndricas, neutrófilos e linfócitos. No grupo de animais doentes havia menor número de macrófagos, e predomínio da população de neutrófilos. Por ser de fácil realização, pouco dispendiosa e pela obtenção representativa de material, a técnica estudada mostrou-se eficaz na obtenção de fluidos traqueobrônquicos e, portanto um bom método de colheita de células para uso nas pesquisas de vias aéreas.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Stress can cause economic losses due to lower weight gain and increased susceptibility of animal diseases. Among the events that cause stress in calves, stand out weaning and road transport, which can result in increased serum concentrations of adrenaline and / or cortisol. This study evaluated the influence of weaning and road transport on the leukogram of Nelore calves. With this purpose, 30 calves with seven to eight months of age, divided into three groups, the first being composed of lactating animals (GL), the second by weaning animals (GD) and the third by weaning animals subjected to road transport for four hours (GDT). The first day of weaning, but not in subsequent days, there were changes in GD and GDT leukogram compatible with the action of adrenaline, as significant increases counts of WBC and neutrophils (p < 0.05), without changing in the neutrophil lymphocytes ratio (NL). In the GDT, immediately after transport, but not in subsequent days, leukogram changes were (p < 0.05) compatible with the action of cortisol, as higher N: L ratio and decreased eosinophil count. It was concluded that, under the conditions of this experiment, there are changes in leukocytes on weaning and road transport related to the action of adrenaline and road transport, respectively, and that the WBC can be used as an indicator of stress in this species.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Purpose: To evaluate the effects of mechanical ventilation (MV) of high-oxygen concentration in pulmonary dysfunction in adult and elderly rats. Methods: Twenty-eight adult (A) and elderly (E), male rats were ventilated for 1 hour (G-AV1 and G-EV1) or for 3 hours (G-AV3 and G-EV3). A and E groups received a tidal volume of 7 mL/kg, a positive end-expiratory pressure of 5 cm H2O, respiratory rate of 70 cycles per minute, and an inspiratory fraction of oxygen of 1. We evaluated total protein content and malondialdehyde in bronchoalveolar lavages (BAL) and performed lung histomorphometrical analyses. Results: In G-EV1 animals, total protein in BAL was higher (33.0 +/- 1.9 mu g/mL) compared with G-AV1 (23.0 +/- 2.0 mu g/mL). Upon 180 minutes of MV, malondialdehyde levels increased in elderly (G-EV3) compared with adult (G-AV3) groups. Malondialdehyde and total proteins in BAL after 3 hours of MV were higher in elderly group than in adults. In G-EV3 group we observed alveolar septa dilatation and significative increase in neutrofiles number in relation to adult group at 60 and 180 minutes on MV. Conclusion: A higher fraction of inspired oxygen in short courses of mechanical ventilation ameliorates the parameters studied in elderly lungs.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Objective-To establish reference intervals for cytologic and biochemical variables in peritoneal fluid, whole blood, and plasma in calves with congenital umbilical hernias (CUHs) before and after herniorrhaphy and to assess whether those variables in calves with CUHs were altered, compared with findings in clinically normal calves.Animals-20 Holstein calves with or without a CUH.Procedures-10 calves with CUHs underwent herniorrhaphy. Blood and peritoneal fluid samples from all 20 calves were collected for cytologic and biochemical analyses on days 0 (before surgery), 1, 3, 5, 7, and 15. Data from the 2 groups were compared.Results-Reference intervals for the variables of interest were established for each group, Before surgery, calves with CUHs had significantly greater plasma total protein concentration and creatine kinase (CK) and aspartate aminotransferase activities and peritoneal fluid specific gravity values, compared with values for calves without CUHs. At various time points after surgery, peritoneal fluid total protein concentration; fibrinogen concentration; nucleated cell, polymorphonuclear cell, and lymphocyte counts; specific gravity; and lactate dehydrogenase, aspartate aminotransferase, and CK activities in calves with CUHs were significantly different from values in calves without CUHs. Some plasma and blood variables leg, total protein concentration, neutrophil count, and CK activity were significantly different between the 2 groups.Conclusions and Clinical Relevance-Values of certain cytologic and biochemical variables in peritoneal fluid, blood, and plasma were different between calves with and without CUHs. Thus, determination of reference intervals for these variables is important for interpreting diagnostic test results in calves with CUHs. (Am J Vet Res 2009;70:423-432)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

O presente trabalho tem como objetivo testar a hipótese de que, à semelhança do que ocorre na uremia, cães com azotemia pré-renal sofrem estresse oxidativo, o qual está relacionado com alterações do metabolismo oxidativo e apoptose dos neutrófilos. Para tal, foi determinada a peroxidação lipídica pela quantificação do malondialdeído (MDA) e o status antioxidante total do plasma de 15 cães normais e 10 com azotemia pré-renal, correlacionando-os com a produção de superóxido e o índice apoptótico dos neutrófilos. As determinações do MDA e do status antioxidante total foram estabelecidas empregando-se um conjunto de reagentes comerciais. Por meio de citometria de fluxo capilar, a produção de superóxido e a apoptose de neutrófilos isolados de sangue periférico foram determinadas utilizando-se a sonda hidroetidina e o sistema anexina V-PE, respectivamente. Cães azotêmicos (26,29±5,32g/L) apresentaram menor concentração (p=0,0264) do antioxidante albumina em relação ao grupo-controle (30,36±3,29g/L) e também uma menor (p=0,0027) capacidade antioxidante total (2,36±0,32 versus 2,73±0,24mmol/L), enquanto não houve alteração da peroxidação lipídica plasmática e da produção de superóxido neutrofílica. Concluiu-se que, à semelhança do que ocorre na uremia, condições azotêmicas pré-renais no cão causam estresse oxidativo e aceleração da apoptose dos neutrófilos.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Ethanol-induced oxidative damage is commonly associated with the generation of reactive oxygen molecules, leading to oxidative stress. Considering that antioxidant activity is an important mechanism of action involved in cytoprotection, the aim of this work was to evaluate the antioxidant properties of the alkaloid indigo (1) (2 mg/kg, p. o.), obtained from the leaves of Indigofera truxillensis Kunth (Fabaceae), on rat gastric mucosa submitted to ethanol-induced (100%, 1 mL, p.o.) gastric ulcer. Enzymatic assays and DNA fragmentation analysis were performed. When ethanol was administered to the control group, the sulfhydryl content (SH) and the glutathione peroxidase (GPx) activity decreased by 41% and 50%, respectively; in contrast, superoxide dismutase (SOD) and glutathione reductase (GR) activities increased by 56% and 67%, respectively. Additionally, myeloperoxidase (MPO) activity, a marker for free radical generation caused by polymorphonuclear neutrophil (PMN) tissue infiltration, also increased 4.5-fold after ethanol treatment. Rat gastric mucosa exposed to ethanol showed DNA fragmentation. Indigo alkaloid pretreatment protected rats from ethanol-induced gastric lesions. This effect was determined by the ulcerative lesion area (ULA), indicating an inhibition of around 80% at 2 mg/kg. This alkaloid also diminished GPx activity, which was higher than that observed with ethanol alone. However, this effect was counterbalanced by increased GR activity. Indigo was unable to restore alterations in SOD activity promoted by ethanol. After indigo pretreatment, SH levels and MPO activity remained normal and gastric mucosa DNA damage caused by ethanol was also partially prevented by indigo. These results suggest that the gastroprotective mechanisms of indigo include non-enzymatic antioxidant effects and the inhibition of PMN infiltration which, in combination, partially protect the gastric mucosa against ethanol-induced DNA damage.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Leukotrienes are classic inflammatory response mediators considered chemotactic agents and microbicidal activity regulators in cells of the innate immune system, playing a protective role against different infectious agents. In this study, we investigated the involvement of leukotrienes in the course of murine paracoccidioidomycosis based on the following immunologic parameters: cell influx, mieloperoxydase activity, NO production, cytokine production, and fungal recovery in lungs of mice selected according to the intensity of their low (AIRmin) and high (AIRmax) acute inflammatory response. Infection by P. brasiliensis induced considerable production of IL-6, IL-10, IFN-gamma and TNF-alpha cytokines, and led to cell recruitment, as well as NO production in lungs at different study periods. In animals treated with MK886, a leukotriene biosynthesis inhibitor, IFN-gamma, IL-6 and TNF-alpha production was lower, while neutrophil influx and NO production decreased. These results may explain the higher fungal load in lungs of animals in which leukotriene synthesis was inhibited, suggesting that leukotrienes have a possible protective role in experimental paracoccidioidomycosis. AIRmax animals had lower fungal load in comparison with AIRmin ones, which can be related to the AIR phenotype regarding neutrophil migration, besides lower production of NO and pro-inflammatory cytokines. Thus, mice presenting AIRmax background are more resistant to infection by P. brasiliensis.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Interleukin-15 is a cytokine produced by a wide range of different cell types, including macrophages, in response to lipopolysaccharide or microbial infection. This cytokine may play a crucial role in the activation of phagocytic cells against pathogens, especially during innate immune response. The effects of IL-15 on human polymorphonuclear leukocyte fungicidal activity against a highly virulent Paracoccidioides brasiliensis strain were investigated. Pretreatment of human neutrophils from healthy individuals with IL-15 for IS h increased cell fungicidal activity in a dose-dependent manner. In addition, the exposure to IL-15 induced an increase in neutrophil oxidative burst as evaluated by superoxide anion and H(2)O(2) release. Catalase inhibited fungicidal activity supporting a role for H(2)O(2) in fungus killing. In contrast, IL-8 and TNF-alpha levels were not affected by IL-15 suggesting that its effects were not mediated by these cytokines. Together, these results show that IL-15 is a potent stimulant of antifungal activities in human neutrophils, at least in part by a mechanism dependent on oxidative metabolism. (c) 2007 Elsevier Ltd. All rights reserved.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background: Biopharmaceutical drugs are mainly recombinant proteins produced by biotechnological tools. The patents of many biopharmaceuticals have expired, and biosimilars are thus currently being developed. Human granulocyte colony stimulating factor (hG-CSF) is a hematopoietic cytokine that acts on cells of the neutrophil lineage causing proliferation and differentiation of committed precursor cells and activation of mature neutrophils. Recombinant hG-CSF has been produced in genetically engineered Escherichia coli ( Filgrastim) and successfully used to treat cancer patients suffering from chemotherapy-induced neutropenia. Filgrastim is a 175 amino acid protein, containing an extra N-terminal methionine, which is needed for expression in E. coli. Here we describe a simple and low-cost process that is amenable to scaling-up for the production and purification of homogeneous and active recombinant hG-CSF expressed in E. coli cells.Results: Here we describe cloning of the human granulocyte colony-stimulating factor coding DNA sequence, protein expression in E. coli BL21(DE3) host cells in the absence of isopropyl-beta-D-thiogalactopyranoside ( IPTG) induction, efficient isolation and solubilization of inclusion bodies by a multi-step washing procedure, and a purification protocol using a single cationic exchange column. Characterization of homogeneous rhG-CSF by size exclusion and reverse phase chromatography showed similar yields to the standard. The immunoassay and N-terminal sequencing confirmed the identity of rhG-CSF. The biological activity assay, in vivo, showed an equivalent biological effect (109.4%) to the standard reference rhG-CSF. The homogeneous rhG-CSF protein yield was 3.2 mg of bioactive protein per liter of cell culture.Conclusion: The recombinant protein expression in the absence of IPTG induction is advantageous since cost is reduced, and the protein purification protocol using a single chromatographic step should reduce cost even further for large scale production. The physicochemical, immunological and biological analyses showed that this protocol can be useful to develop therapeutic bioproducts. In summary, the combination of different experimental strategies presented here allowed an efficient and cost-effective protocol for rhG-CSF production. These data may be of interest to biopharmaceutical companies interested in developing biosimilars and healthcare community.