Background: Respiratory syncytial virus (RSV) is a common respiratory pathogen that can cause severe pneumonia. In vivo studies of RSV can be difficult due to variation in viral infection and disease severity in some animal models. Factors that may contribute to the variation are decreases in viral titer due to preparation and storage and method of virus administration. Nebulization is one method of RSV administration that provides even distribution of virus to all lung lobes; however, the exact quantity of the virus killed by nebulization is not defined. To test the hypothesis that sucrose enhances RSV stability and infectivity, a series of in vitro experiments were conducted with RSV strain Memphis 37 stored at varying concentrations (0%, 3%, 5%, 8%, 10%, 15%, and 20%) of sucrose as a possible cryo- and nebulization protectant. The optimal in vitro concentration was then assessed in vivo in a lamb model.
Methods: Prior to titering the virus on HEp-2 cells, the various virus solutions were subjected to one freeze-thaw cycle and one nebulization cycle. Forty-eight hours after viral plating, infectious foci were detected and counted using immunofluorescent imaging. Titers were determined after freeze-thaw and after freeze-thaw followed by nebulization, then compared to the stock titers (before freezing) as well as to one another to determine the loss of infectivity. To further test this in vivo, lambs 2 to 3-days-old were infected via nebulization with RSV using inoculate containing either 20% sucrose or no sucrose followed by assessments of infection severity.
Results: Nebulization of virus in 0% sucrose resulted in a 0.580 log reduction in infectivity while virus in 20% sucrose exhibited a 0.297 log reduction. In vivo studies demonstrated that 20% sucrose enhanced RSV lesions and antigen distribution.
Conclusions: The data suggests that both nebulization and freeze-thawing of RSV in the absence of sucrose cause unacceptable losses in viral infectivity and that sucrose acts as a RSV protectant in both regards.
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http://dx.doi.org/10.1186/1756-0500-7-158 | DOI Listing |
Plants (Basel)
December 2024
Laboratório da Interação Planta-Patógeno, Departamento de Fitopatologia, Universidade Federal de Viçosa, Viçosa 36570-900, Minas Gerais, Brazil.
Maize leaf blight (MLB), caused by the fungus , is an important disease affecting maize production. In order to minimize the use of fungicides in agriculture, nutrient-based resistance inducers may become a promising alternative to manage MLB. The goal of this study was to investigate the potential of Semia (zinc (20%) complexed with a plant-derived pool of polyphenols (10%)) to hamper the infection of maize leaves by by analyzing their photosynthetic performance and carbohydrate and antioxidative metabolism, as well as the expression of defense-related genes.
View Article and Find Full Text PDFAnal Biochem
January 2025
Laboratorio de Biología Estructural y Molecular BEM, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425 Ñuñoa, Santiago, 7800003, Chile; Laboratorio de Biotecnología Vegetal y Ambiental Aplicada, Universidad Tecnológica Metropolitana, Santiago, Chile.
FtsZ is a bacterial protein that plays a crucial role in cytokinesis by forming the Z-ring. This ring acts as a scaffold to recruit other division proteins and guide the synthesis of septal peptidoglycan, which leads to cell constriction. In its native state, the FtsZ protein from Escherichia coli (EcFtsZ) is a multi-oligomer comprising dimers, trimers, tetramers, and hexamers in a dynamic self-association equilibrium depending on its concentration.
View Article and Find Full Text PDFDiabetologia
January 2025
Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
Aims/hypothesis: A positive association between sugar-sweetened beverages (SSBs) and diabetes risk has been shown, with inconsistent evidence between artificially sweetened beverages (ASBs) and diabetes. Moreover, it is uncertain if physical activity can mitigate the negative effects of these beverages on diabetes development. Therefore, we aimed to evaluate the independent and joint associations between SSB or ASB consumption and physical activity on the risk of type 2 diabetes.
View Article and Find Full Text PDFPlants (Basel)
December 2024
State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Roses are one of the most important flowers applied to landscape, cut flowers, fragrance and food industries widely. As an effective method for plant reproduction, the regeneration via somatic embryos is the most promising method for breed improvement and genetic transformation of woody plants. However, lower somatic embryogenesis (SE) induction rates and genotypic constraints impede progress in genetic transformation in rose.
View Article and Find Full Text PDFInsects
November 2024
Meliponini and Apini Research Laboratory, Department of Entomology and Plant Pathology, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand.
Climate change significantly affects honey bee populations and their access to natural food sources, demanding alternative economic feed sources. Longan stands out as the most important fruit crop in Southeast Asia, but with a surplus of low-grade fruit that is not suitable for the market. This study investigates the potential of longan syrup as an alternative carbohydrate source for honey bees by measuring sugar composition, phytochemical profiles, feed, and survival, as well as the resulting gut microbial changes.
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