1,678 research outputs found
Hyperoxic acute lung injury and ventilator-induced/associated lung injury: new insights into intracellular signaling pathways
In patients with acute respiratory distress syndrome (ARDS), supportive therapy with mechanical ventilation and oxygen is often life saving. Further acute lung injury however, is an unfortunate consequence of oxygen therapy as well as mechanical injury secondary to ventilator induced/associated lung injury (VI/ALI). In this issue of Critical Care, Li et al. expand on the intra-cellular signaling pathways regulating interactions between injury cascades resulting from hyperoxia and high tidal volume ventilation. The findings, suggest that interference or cooperation of different signals may have critical consequences as evidenced by indices of increased lung inflammation, microvascular permeability, and lung epithelial apoptotic cell death
Bench-to-bedside review: Biotrauma and modulation of the innate immune response
The innate immune network is responsible for coordinating the initial defense against potentially noxious stimuli. This complex system includes anatomical, physical and chemical barriers, effector cells and circulating molecules that direct component and system interactions. Besides the direct effects of breaching pulmonary protective barriers, cyclic stretch generated during mechanical ventilation (MV) has been implicated in the modulation of the innate immunity. Evidence from recent human trials suggests that controlling MV-forces may significantly impact outcome in acute respiratory distress syndrome. In this paper, we explore the pertinent evidence implicating biotrauma caused by cyclic MV and its effect on innate immune responses
Avaliação da infiltração de água no solo pelo método de infiltrômetro de anel no agreste alagoano
A infiltração de água no solo é o processo de entrada de água através da superfície do solo. O conhecimento da taxa de infiltração da água no solo é de fundamental importância para definir técnicas de conservação do solo, planejar e delinear sistemas de irrigação e drenagem, bem como auxiliar na composição de uma imagem mais real da retenção da água e aeração no solo. O presente trabalho teve como objetivo determinar as curvas de infiltração e velocidade de infiltração de água pelo método de infiltrômetro de anel em um solo do agreste alagoano. O Infiltrômetro de anel é um equipamento composto por dois anéis (50 e 25 cm de diâmetro e 30 cm de altura), que são instalados de forma concêntrica e enterrados a 15 cm. Pode-se concluir que o método de infiltrômetro de anel é simples e prático para determinação da infiltração acumulada (I) e a velocidade de infiltração (VI). O solo foi caracterizado como Argissolo Vermelho distrófico e sua VIB (velocidade de infiltração básica) foi classificada como alta (2 cm h-1)
Low CXCL13 Expression, Splenic Lymphoid Tissue Atrophy and Germinal Center Disruption in Severe Canine Visceral Leishmaniasis
Visceral leishmaniasis is associated with atrophy and histological disorganization of splenic compartments. In this paper, we compared organized and disorganized splenic lymphoid tissue from dogs naturally infected with Leishmania infantum assessing the size of the white pulp compartments, the distribution of T, B and S100+ dendritic cells, using immunohistochemistry and morphometry and the expression of CCR7 and the cytokines, CXCL13, lymphotoxin (LT)-α, LT-β, CCL19, CCL21, TNF-α, IL-10, IFN-γ and TGF-β, using by real time RT-PCR. The lymphoid follicles and marginal zones were smaller (3.2 and 1.9 times, respectively; Mann-Whitney, P<0.02) in animals with disorganized splenic tissue in comparison to those with organized splenic lymphoid tissue. In spleens with disorganized lymphoid tissue, the numbers of T cells and S100+ dendritic cells were decreased in the follicles, and the numbers of B cells were reduced in both the follicles and marginal zones. CXCL13 mRNA expression was lower in animals with disorganized lymphoid tissue (0.5±0.4) compared to those with organized lymphoid tissue (2.7±2.9, both relative to 18S expression, P = 0.01). These changes in the spleen were associated with higher frequency of severe disease (7/12) in the animals with disorganized than in animals with organized (2/13, Chi-square, P = 0.01) splenic lymphoid tissue. The data presented herein suggest that natural infection with Leishmania infantum is associated with the impairment of follicular dendritic cells, CXCL13 expression, B cell migration and germinal center formation and associates these changes with severe clinical forms of visceral leishmaniasis. Furthermore the fact that this work uses dogs naturally infected with Leishmania infantum emphasizes the relevance of the data presented herein for the knowledge on the canine and human visceral leishmaniasis
Individual in vitro effects of ochratoxin A, deoxynivalenol and zearalenone on oxidative stress and acetylcholinesterase in lymphocytes of broiler chickens
The contamination of consumer food and animal feed with toxigenic fungi has resulted in economic losses worldwide in animal industries. Mycotoxins are highly biologically reactive secondary metabolites and can inhibit protein synthesis and cell multiplication. Considering the cytotoxicity of mycotoxins, this experiment was performed to determine the in vitro influence of ochratoxin A, deoxynivalenol and zearalenone on lipid peroxidation in lymphocytes of broiler chickens at different concentrations. This study has also evaluated whether the presence of these mycotoxins changes the acetylcholinesterase activity in lymphocytes, which is involved in the regulation of immune and inflammatory responses. Blood lymphocytes of broiler chickens were isolated through density gradient centrifugation and incubated with the respective mycotoxins at concentrations of 0.001, 0.01, 0.1 and 1 μg/mL. Lipid peroxidation, which was evaluated through the amount of malondialdehyde measured in a thiobarbituric acid-reactive species test, and the enzymatic activity were analyzed at 24, 48 and 72 h. Results of the lipid peroxidation evaluation showed an increasing cytotoxicity relation: ochratoxin A > deoxynivalenol > zearalenone. Conversely, cytotoxicity was valued as zearalenone > deoxynivalenol > ochratoxin A in relation to the acetylcholinesterase enzymatic activity. At a concentration of 1 μg/mL, ochratoxin A and deoxynivalenol induced the highest cellular oxidative stress levels and the highest enzymatic activity at the majority of time points. However, the same mycotoxins, except at 1 μg/mL concentration, induced a reduction of lymphocytic lipid peroxidation 72 h after incubation, suggesting the action of a compensatory mechanism in these cells
Lecitase ultra: A phospholipase with great potential in biocatalysis
Lecitase Ultra is a chimera produced by the fusion of the genes of the lipase from Thermomyces lanuginosus and the phospholipase A1 from Fusarium oxysporum. The enzyme was first designed for the enzymatic degumming of oils, as that problem was not fully resolved before. It is commercialized only as an enzyme solution by Novo Nordisk A/S. This review shows the main uses of this promising enzyme. Starting from the original degumming use, the enzyme has found applications in many other food modification applications, like production of structured phospholipids (e.g., derivatives of phosphatidylcholine), tuning the properties of flour, etc. Moreover, the enzyme has been used in fine chemistry (resolution of racemic mixtures), in the production of aromas and fragrances, polymers modification, etc. Some papers show the use of the enzyme in biodiesel production. Moreover, we present the different technologies applied to obtain a suitable immobilized biocatalyst, remarking the immobilization via interfacial activation and how heterofunctional acyl supports may solve some of the limitations. Immobilized enzyme physical and chemical modifications have also been presented. Finally, Lecitase Ultra has been one of the model enzymes in a new strategy to coimmobilize lipases and other less stable enzymes.We gratefully recognize the financial support from MINECO from Spanish Government (project number CTQ2017-86170-R), Colciencias, Ministerio de Educación Nacional, Ministerio de Industria, Comercio y Turismo e ICETEX, Convocatoria Ecosistema Científico – Colombia Científica. Fondo Francisco José de Caldas, Contrato RC-FP44842-212-2018, Colciencias (Colombia, project number FP 44842-076-2016), Generalitat Valenciana (PROMETEO/2018/076), FAPERGS (project number 17/2551-0000939-8), FUNCAP (project number BP3-0139-00005.01.00/18) and CONACYT (Mexico, project number CB-2016-01, 286992)
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