38 research outputs found

    Histone deacetylases in viral infections

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    Chromatin remodeling and gene expression are regulated by histone deacetylases (HDACs) that condense the chromatin structure by deacetylating histones. HDACs comprise a group of enzymes that are responsible for the regulation of both cellular and viral genes at the transcriptional level. In mammals, a total of 18 HDACs have been identified and grouped into four classes, i.e., class I (HDACs 1, 2, 3, 8), class II (HDACs 4, 5, 6, 7, 9, 10), class III (Sirt1–Sirt7), and class IV (HDAC11). We review here the role of HDACs on viral replication and how HDAC inhibitors could potentially be used as new therapeutic tools in several viral infections

    Characterization of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection clusters based on integrated genomic surveillance, outbreak analysis and contact tracing in an urban setting

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    BACKGROUND: Tracing of SARS-CoV-2 transmission chains is still a major challenge for public health authorities, when incidental contacts are not recalled or are not perceived as potential risk contacts. Viral sequencing can address key questions about SARS-CoV-2 evolution and may support reconstruction of viral transmission networks by integration of molecular epidemiology into classical contact tracing. METHODS: In collaboration with local public health authorities, we set up an integrated system of genomic surveillance in an urban setting, combining a) viral surveillance sequencing, b) genetically based identification of infection clusters in the population, c) integration of public health authority contact tracing data, and d) a user-friendly dashboard application as a central data analysis platform. RESULTS: Application of the integrated system from August to December 2020 enabled a characterization of viral population structure, analysis of four outbreaks at a maximum care hospital, and genetically based identification of five putative population infection clusters, all of which were confirmed by contact tracing. The system contributed to the development of improved hospital infection control and prevention measures and enabled the identification of previously unrecognized transmission chains, involving a martial arts gym and establishing a link between the hospital to the local population. CONCLUSIONS: Integrated systems of genomic surveillance could contribute to the monitoring and, potentially, improved management of SARS-CoV-2 transmission in the population

    Integrated genomic surveillance enables tracing of person-to-person SARS-CoV-2 transmission chains during community transmission and reveals extensive onward transmission of travel-imported infections, Germany, June to July 2021

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    BackgroundTracking person-to-person SARS-CoV-2 transmission in the population is important to understand the epidemiology of community transmission and may contribute to the containment of SARS-CoV-2. Neither contact tracing nor genomic surveillance alone, however, are typically sufficient to achieve this objective.AimWe demonstrate the successful application of the integrated genomic surveillance (IGS) system of the German city of DĂŒsseldorf for tracing SARS-CoV-2 transmission chains in the population as well as detecting and investigating travel-associated SARS-CoV-2 infection clusters.MethodsGenomic surveillance, phylogenetic analysis, and structured case interviews were integrated to elucidate two genetically defined clusters of SARS-CoV-2 isolates detected by IGS in DĂŒsseldorf in July 2021.ResultsCluster 1 (n = 67 DĂŒsseldorf cases) and Cluster 2 (n = 36) were detected in a surveillance dataset of 518 high-quality SARS-CoV-2 genomes from DĂŒsseldorf (53% of total cases, sampled mid-June to July 2021). Cluster 1 could be traced back to a complex pattern of transmission in nightlife venues following a putative importation by a SARS-CoV-2-infected return traveller (IP) in late June; 28 SARS-CoV-2 cases could be epidemiologically directly linked to IP. Supported by viral genome data from Spain, Cluster 2 was shown to represent multiple independent introduction events of a viral strain circulating in Catalonia and other European countries, followed by diffuse community transmission in DĂŒsseldorf.ConclusionIGS enabled high-resolution tracing of SARS-CoV-2 transmission in an internationally connected city during community transmission and provided infection chain-level evidence of the downstream propagation of travel-imported SARS-CoV-2 cases

    APLICAÇÃO DO SORO DE LEITE EM PÓ NA PANIFICAÇÃO

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    <p align="justify">Para o aproveitamento dos constituintes nutricionais do soro de leite, no presente trabalho efetuouse a secagem de soro de leite por atomização (spray dryer - Lab Plant SD - 05), caracterização do produto e aplicação em produto de panificação. As condiçÔes operacionais de secagem foram: temperatura e vazĂŁo do ar de secagem, 190 ÂșC e 75 m3/h; pressĂŁo de atomização do soro de 0,08 bar; vazĂŁo mĂ©dia de alimentação do soro de 0,5 L/h. O soro desidratado apresentou em mĂ©dia 3,6 % de umidade, 48,84 % de lactose, 12,8 % de proteĂ­na, 6,6 % de gordura e 7,1 % de sais minerais. Com o soro desidratado, formularam-se pĂŁes de leite, substituindo-se o leite em pĂł por soro de leite nas proporçÔes de 25, 50, 75 e 100 %, respectivamente. Os produtos foram avaliados sensorialmente, por uma equipe de 35 provadores nĂŁo treinados. A substituição do leite em pĂł desnatado pelo soro de leite desidratado ocasionou uma diminuição no teor de cĂĄlcio e aumentou nos teores de gordura e sĂłdio nas formulaçÔes de pĂŁo de leite. A formulação com 25 % de soro de leite desidratado apresentou as melhores caracterĂ­sticas de sabor e aceitação geral (69 %)

    Effect of apparent viscosity on fluidized bed drying process parameters of guava pulp

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    Pressure drop and minimum fluidization velocity were experimentally studied in a vibro-fluidized bed of inert particles subjected to different vibration intensities during drying of guava pulp. Maltodextrin was added to the pulp in order to prevent stickiness between particles and the consequent bed collapse. Pulps were initially concentrated, resulting in pastes with different soluble solids content, and a constant fraction of maltodextrin was guaranteed in the final pulp samples. The pulp rheological behavior as affected by temperature and total soluble solids content, including maltodextrin, was evaluated and the effect of pulp apparent viscosity on pressure drop and minimum vibro-fluidization velocity were investigated. Two types of inert particles -3.6 mm glass beads and 3 mm Teflon cylinders were tested and, due to lower pressure drop presented by Teflon cylinders during operation of the dry vibro-fluidized bed, these particles were adopted for pulp drying process. Increasing pulp apparent viscosity caused a considerable increase in the vibro-fluidized bed pressure drop during pulp drying and, as a consequence resulted in a larger value of minimum vibro-fluidization velocity. on the other hand, the negative effect of increasing apparent viscosity could be attenuated by increasing the fluidized bed vibration intensity, which could prevent stickiness between particles. (c) 2006 Elsevier Ltd. All rights reserved
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