Type I interferons in tuberculosis: Foe and occasionally friend

Tuberculosis remains one of the leading causes of mortality worldwide, and, despite its clinical significance, there are still significant gaps in our understanding of pathogenic and protective mechanisms triggered by Mycobacterium tuberculosis infection. Type I interferons (IFN) regulate a broad family of genes that either stimulate or inhibit immune function, having both host-protective and detrimental effects, and exhibit well-characterized antiviral activity. Transcriptional studies have uncovered a potential deleterious role for type I IFN in active tuberculosis. Since then, additional studies in human tuberculosis and experimental mouse models of M. tuberculosis infection support the concept that type I IFN promotes both bacterial expansion and disease pathogenesis. More recently, studies in a different setting have suggested a putative protective role for type I IFN. In this study, we discuss the mechanistic and contextual factors that determine the detrimental versus beneficial outcomes of type I IFN induction during M. tuberculosis infection, from human disease to experimental mouse models of tuberculosis

Derivation of an Abelian effective model for instanton chains in 3D Yang-Mills theory

In this work, we derive a recently proposed Abelian model to describe the interaction of correlated monopoles, center vortices, and dual fields in three dimensional SU(2) Yang-Mills theory. Following recent polymer techniques, special care is taken to obtain the end-to-end probability for a single interacting center vortex, which constitutes a key ingredient to represent the ensemble integration.Comment: 18 pages, LaTe

Ohmic heating treatment of fruit puree

Ohmic heating is an alternative pasteurization process and is growing interest in industry. Understanding the influence of ohmic heating on the sensorial and microbiological quality of foods is a pertinent matter. This study concerns with the pasteurization effects of a pilot scale continuous ohmic heater on a strawberry puree containing fruit particles on relevant quality parameters of the product. The impact of pasteurization temperature (85 ºC, 90 ºC, 95 ºC) on the microbiological load, size distribution of strawberry particles (1 g), texture and microbial stability was studied. All treatments destroyed yeasts and moulds to values below 10 CFU/mL. The strawberry particles size distribution shows that the average size of particles decreased with increasing treatment temperature. A texture reduction, measured in terms of the force applied on a 5-blade Kramer cell, was observed when strawberry particles were collected before and after the thermal treatment: 20 %, 23 % and 25 % reduction at 85 ºC, 90 ºC and 95 ºC, respectively. The reduction for a scrapped surface heat-exchanger treatment at 95 ºC was of 31 %. In conclusion, ohmic heating reduces the product microbiological load and for parameters such as texture and size distribution of the strawberry particles the cooking effects are reduced when compared with a scrapped surface heat-exchanger treatment.Ao longo das últimas décadas o aquecimento óhmico tem vindo a ganhar interesse por parte da indústria. Assim, torna-se necessário compreender a influência do aquecimento óhmico nas propriedades sensoriais e microbiológicas dos alimentos. O principal objectivo deste trabalho é a análise dos efeitos de pasteurização contínua realizada num aquecedor óhmico à escala piloto. Foram estudados os efeitos de diferentes temperaturas de pasteurização (85 ºC, 90 ºC, 95 ºC) na carga microbiana, na integridade dos pedaços de morango, na textura e na estabilidade microbiana. Todos os tratamentos efectuados reduzem os valores de fungos e leveduras para valores inferiores a 10 UFC/mL. A análise da integridade dos pedaços de morango revelou que o tamanho médio dos pedaços diminui com o aumento da temperatura de tratamento. Foi também detectada uma redução da textura, medida em termos de força aplicada numa célula de Kramer de 5 lâminas, em relação à textura dos pedaços antes do tratamento: esta diminuiu 20 %, 23 % e 25 % para os tratamentos a 85 ºC, 90 ºC e 95 ºC, respectivamente. Esta redução foi ainda superior (31 %) para as amostras submetidas ao tratamento realizado num permutador de superfície raspada a 95 ºC. Com a realização deste trabalho foi possível concluir que utilizando a tecnologia de aquecimento óhmico é possível reduzir a carga microbiana e que os efeitos de cozedura excessiva são atenuados quando comparado com um tratamento efectuado num permutador de superfície raspada