Thermal inactivation of Byssochlamys nivea in pineapple nectar combined with preliminary high pressure treatments

Byssochlamys nivea is a thermal resistant filamentous fungi and potential micotoxin producer. Recent studies have verified the presence of ascospores of such microorganism in samples of pineapple nectars. Although the majority of filamentous fungi have limited heat resistance and are easily destroyed by heat, Byssochlamys nivea ascospores have shown high thermal resistance. The aim of this work was to evaluate the application of linear and Weibull models on thermal inactivation (70, 80 and 90ºC) of Byssochlamys nivea ascospores in pineapple nectar after pretreatment with high pressure (550MPa or 650MPa during 15min). Following the treatments, survival curves were built up for each processing temperature and adjusted for both models. It was observed that survival curves at 90°C after high pressure pretreatment at 550 MPa/15 min did not fit well to linear and Weibull models. For all the other treatments, the Weibull model presented a better fit. At 90ºC without pressure treatment, the Weibull model also showed a better adjustment, having a larger R2 and a smaller RMSE. Regarding the process effectiveness, a 5-log reduction (t5), as recommended for pasteurization, was only achieved for Byssochlamys nivea ascospores presented in pineapple nectar at 90ºC/10.7 min with previous high pressure treatment of 650 MPa for 15 min. Considering the high intensity and energy demanding process with possibly product damage, other preventive and alternative treatments are being investigated

Research on quality management and sustainability

Purpose - This article aims to ascertain the necessity for specific research on quality management approaches, bringing to the discussion some concerns and challenges to the quality movement, especially in development of new methodologies for supporting design in the digital area. Design/methodology/approach - Firstly, papers were researched that had already studied the question of what research should carry out in response to the great scientific, technical, and social changes, specifically to support design activities for internet products and secondly we concluded what development is needed. Findings - The increasing complexity of management and technology creates many situations of anxiety and distress, which often translate into abandonment of proven techniques and methodologies, leading to intuitive approaches. But complexity requires more techniques and methodologies not less. The quality movement faces a serious challenge: how to design in an ethical perspective these types of products. Research limitations/implications - This research is limited to identify some needs, but future research should be done in characterizing existing answers and identifying what development is needed. Practical implications - The above findings and reflections can help other researchers to focus on design, to find out practical solutions for sustainability in the innovation process of products and services. Social implications - Finding out to design in an ethical perspective products and services for internet. Originality/value - This research identified relevant challenges the quality management is facing, and it gives guidelines for defining research lines.info:eu-repo/semantics/publishedVersio

Dor visceral intensa associada a desnervação simpática renal seletiva: um desafio

Introdução e Objetivos: A desnervação simpática renal seletiva (DSRS) é um procedimento endovascular minimamente invasivo, seguro, recentemente desenvolvido para o tratamento da hipertensão resistente (HR). Até 6 ablações por radiofrequência (RF), com 2 minutos cada são aplicadas em ambas as artérias renais, estando associadas a dor abdominal visceral difusa, muito intensa1,2. Não foi encontrada literatura sobre o manuseamento anestésico deste procedimento. O nosso objetivo é descrever a experiência do nosso departamento na DSRS e sugerir uma abordagem anestésica (AA) adequada para o procedimento. Metodologia: Foram colhidos, retrospetivamente, os dados dos doentes com HR submetidos a DSRS na nossa instituição até novembro de 2012. Variáveis analisadas: dados demográficos, co-morbilidades, estadio físico da American Society of Anesthesiology (ASA-EF), abordagem anestésica e complicações peri-procedimento. Foi também realizada uma revisão bibliográfica na PubMed sobre DSRS e outros procedimentos endovasculares para identificar uma AA apropriada e eficiente para DSRS. Resultados: 16 doentes (9 homens/7 mulheres), idade 59,7 ± 10 anos. ASA-EF II 25%, III 75%. 14 doentes foram submetidos a cuidados anestésicos monitorizados (MAC): 6 com perfusão remifentanil (0.05 a 0.15μg/Kg/min com bólus até 1μ/Kg durante as ablações), 8 com bólus de propofol (até 150mg) associado a bólus de fentanil (até 150μg) e midazolam (1 a 2 mg). 1 doente foi sujeito a anestesia geral balanceada e 1 doente a bloqueio subaracnoideu. O procedimento anestésico durou 75 ± 16 minutos. O procedimento foi considerado bem sucedido em todos os doentes. Não foram observadas complicações. Discussão e Conclusão: Os 2 principais estudos publicados sobre DSRS (Simplicity trials) referem o uso de opiáceos e sedativos intravenosos para o tratamento da dor associada às ablações. Os fármacos usados e respetivas doses não são descritos. As várias AA usadas na nossa instituição refletem a ausência de literatura anestésica sobre a DSRS. A AA mais adequada depende das caraterísticas dos doentes e do tipo de dor associada (intensa, aguda e intermitente) e deve assegurar o máximo conforto do doente, segurança e sucesso técnico do procedimento. Pela nossa análise, a literatura revista e a experiência adquirida noutros procedimentos com dor semelhante consideramos que o remifentanil, pelas suas propriedades farmacológicas únicas, é adequado para o AA da DSRS. Remifentanil nas doses de 0.05 a 0.15μg/Kg/min com bólus até 1μ/Kg durante as ablações parece apropriado. São necessários mais estudos para melhor avaliação

Nitrosative stress defences of the enterohepatic pathogenic bacterium Helicobacter pullorum

Helicobacter pullorum is an avian bacterium that causes gastroenteritis, intestinal bowel and hepatobiliary diseases in humans. Although H. pullorum has been shown to activate the mammalian innate immunity with release of nitric oxide (NO), the proteins that afford protection against NO and reactive nitrogen species (RNS) remain unknown. Here several protein candidates of H. pullorum, namely a truncated (TrHb) and a single domain haemoglobin (SdHb), and three peroxiredoxin-like proteins (Prx1, Prx2 and Prx3) were investigated. We report that the two haemoglobin genes are induced by RNS, and that SdHb confers resistance to nitrosative stress both in vitro and in macrophages. For peroxiredoxins, the prx2 and prx3 expression is enhanced by peroxynitrite and hydrogen peroxide, respectively. Mutation of prx1 does not alter the resistance to these stresses, while the single ∆prx2 and double ∆prx1∆prx2 mutants have decreased viability. To corroborate the physiological data, the biochemical analysis of the five recombinant enzymes was done, namely by stopped-flow spectrophotometry. It is shown that H. pullorum SdHb reacts with NO much more quickly than TrHb, and that the three Prxs react promptly with peroxynitrite, Prx3 displaying the highest reactivity. Altogether, the results unveil SdHb and Prx3 as major protective systems of H. pullorum against nitrosative stress

Isolamento de novas estirpes de Bacillus thuringiensis e Bacillus thuringiensis para o controle de Culex quinquefasciatus e Aedes aegypti.

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Membrane Type 1 Matrix Metalloproteinase Regulates Monocyte Migration and Collagen Destruction in Tuberculosis

Tuberculosis (TB) remains a global pandemic and drug resistance is rising. Multicellular granuloma formation is the pathological hallmark of Mycobacterium tuberculosis infection. The membrane type 1 matrix metalloproteinase (MT1-MMP or MMP-14) is a collagenase that is key in leukocyte migration and collagen destruction. In patients with TB, induced sputum MT1-MMP mRNA levels were increased 5.1-fold compared with matched controls and correlated positively with extent of lung infiltration on chest radiographs (r = 0.483; p < 0.05). M. tuberculosis infection of primary human monocytes increased MT1-MMP surface expression 31.7-fold and gene expression 24.5-fold. M. tuberculosis-infected monocytes degraded collagen matrix in an MT1-MMP-dependent manner, and MT1-MMP neutralization decreased collagen degradation by 73%. In human TB granulomas, MT1-MMP immunoreactivity was observed in macrophages throughout the granuloma. Monocyte-monocyte networks caused a 17.5-fold increase in MT1-MMP surface expression dependent on p38 MAPK and G protein-coupled receptor-dependent signaling. Monocytes migrating toward agarose beads impregnated with conditioned media from M. tuberculosis-infected monocytes expressed MT1-MMP. Neutralization of MT1-MMP activity decreased this M. tuberculosis network-dependent monocyte migration by 44%. Taken together, we demonstrate that MT1-MMP is central to two key elements of TB pathogenesis, causing collagen degradation and regulating monocyte migration

Effect of Water Content on the Thermal Inactivation Kinetics of Horseradish Peroxidase Freeze-Dried from Alkaline pH

The thermal inactivation of horseradish peroxidase freeze-dried from solutions of different pH (8, 10 and 11.5, measured at 25 C) and equilibrated to different water contents was studied in the temperature range from 110 to 150 C. The water contents studied (0.0, 1.4, 16.2 and 25.6 g water per 100 g of dry enzyme) corresponded to water activities of 0.0, 0.11, 0.76 and 0.88 at 4 C. The kinetics were well described by a double exponential model. The enzyme was generally more stable the lower the pH of the original solution, and for all pH values, the maximum stability was obtained at 1.4 g water/100 g dry enzyme. Values of z were generally independent of water content and of the pH of the original solution, and in the range of 15–25 °C, usually found in neutral conditions, with the exception of the enzyme freeze dried from pH 11.5 and equilibrated with phosphorus pentoxide, where a z-value of the stable fraction close to 10 C was found