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The ability of viruses to persist in the environment and on fresh produce, as well as their low infectious doses, allows even a small amount of contamination to cause foodborne viral outbreaks. Human Adenoviruses (hAdVs) of subgroup F (enteric serotypes 40 and 41) are known to be associated with 5-20% worldwide of acute gastroenteritis cases among infants and young children. The present study aimed to evaluate a simple and cost-effective, one-step, single-tube adenovirus type 40/41 specific loop-mediated isothermal amplification (LAMP) assay for the detection of hAdV40/41 DNA in a series of ready-to-eat food samples (strawberries, sour cherries, lettuce, cherry tomatoes and green onions). No LAMP assay has previously been reported for the detection of these virus types in food samples. Results were obtained within 60 min, under isothermal conditions at 69?C. After amplification, the products were detected either by observing a ladder pattern following gel electrophoresis, or a color change with the addition of SYBR Green I to the reaction tube. The limits of detection of hAdV40/41 in food samples were found to be >30 GCs per reaction, when a nucleic acids extraction step was included in the analysis. A 1 log higher (>100 GCs/reaction) detection limit was found for lettuce, cherry tomatoes and green onions, without a nucleic acids extraction step included before the isothermal amplification. The LAMP assay for the virological analysis of food samples is expected to provide a robust, innovative, powerful, cheap and fast monitoring tool, without the need of sophisticated equipment, which will be available for food safety testing by the food industry and the public food health authorities. [ABSTRACT FROM AUTHOR]

In the present study, the effectiveness of two loop-mediated isothermal amplification (LAMP) assays was evaluated. Samples of romaine lettuce, strawberries, cherry tomatoes, green onions and sour berries were inoculated with known dilutions (100-108 CFU/g of product) of S. Enteritidis and L. monocytogenes. With LAMP, assay pathogens can be detected in less than 60 min. The limits of detection of S. Enteritidis and L. monocytogenes depended on the food sample tested and on the presence of enrichment step. After enrichment steps, all food samples were found positive even at low initial pathogen levels. The developed LAMP assays are expected to become a valuable, robust, innovative, powerful, cheap and fast monitoring tool, which can be extensively used for routine analysis, and screening of contaminated foods by the food industry and the Public Food Health Authorities. [ABSTRACT FROM AUTHOR]

The qualitative performance characteristics of a qPCR-based method to detect human adenoviruses in raspberries were determined through a collaborative trial involving 11 European laboratories. The method incorporated a sample process control (murine norovirus) and an internal amplification control. Trial sensitivity or correct identification of 25-g raspberry samples artificially contaminated with between 5 × 10 and 5 × 10 PFU was 98.5%; the accordance and concordance were 97.0%. The positive predictive value was 94.2%. The trial specificity or percentage correct identification of non-artificially contaminated samples was 69.7%; the accordance was 80.0% and the concordance was 61.7%. The negative predictive value was 100%. Application of a method for the detection of human adenoviruses in food samples could be useful for routine monitoring for food safety management. It would help to determine if a route of contamination exists from human source to food supply chain which pathogenic viruses such as norovirus and hepatitis A virus could follow. [ABSTRACT FROM AUTHOR]

The osseointegration process of bone implants crucially depends on the interaction between osteoblasts and the topography of the implant surface. Core binding factor alpha 1 (Cbfa1) is an osteoblast specific transcription factor that regulates osteoblast differentiation and expression of genes necessary for the development of a mineralized phenotype. In this study, we investigated the influence of microfabricated topographies on the activation of Cbfa1, in osteoblasts cultured on titanium substrata presenting microgroove gradients. Surface microgrooves with groove and ridge width ranging from 3 to 300 ?m, and four different groove depths (4, 6, 10, 14 ?m) were patterned on single crystalline silicon wafers using microlithography and deep reactive ion etching (DRIE). Titanium thin films were coated on the microgrooves by radio-frequency magnetron sputtering. All surfaces were characterized using atomic force microscopy (AFM), scanning electron microscopy (SEM), and profilometry. Immunofluorescence staining of Cbfa1 protein was used to study the differentiation and function of osteoblasts in 3 day (72 h) culture experiments. Microtextured titanium surfaces were shown to promote contact guidance and enhanced Cbfa1 expression and activation, independently of the dimensions of the grooves of the studied microgroove gradients, compared to non micropattered surfaces. In conclusion, implant surface microgeometries may contribute to the regulation of osteoblast differentiation and function by influencing the level of bone-related transcription factors such as Cbfa1 in osteoblastic cells. [ABSTRACT FROM AUTHOR]

In this work, the synthesis, characterization, and photocatalytic performance of zinc oxide/activated carbon fiber nanocomposites prepared by hydrothermal method were investigated. Zinc oxide nanoparticles (ZnO-NP) were deposited as seeds on porous activated carbon fiber (ACF) substrates. Then, zinc oxide nanorods (ZnO-NR) were successfully grown on the seeds and assembled on the fibers' surface in various patterns to form ZnO-NR/ACF nanocomposites. The nanocomposites were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectrometry, UV–vis diffuse reflectance spectra (DRS), and Brunauer–Emmett–Teller (BET) surface area analysis. SEM images showed that brush-like and flower-like ZnO-NR patterns were grown uniformly on the ACF surface with sizes depending on the ZnO-NP concentration, growth time, and temperature. The FTIR spectrum confirmed the presence of the major vibration bands, especially the absorption peaks representing the vibration modes of the COOH (C = O and C = C) functional group. Adsorption and photocatalytic activities of the synthesized catalytic adsorbents were compared using methylene blue (MB) as the model pollutant under UV irradiation. ZnO-NR/ACF nanocomposites showed excellent photocatalytic activity (~99% degradation of MB in 2 h) compared with that of bare ZnO-NR and ACF. Additionally, a recycling experiment demonstrated the stability of the catalyst; the catalytic degradation ratio of ZnO-NR/ACF reached more than 90% after five successive runs and possessed strong adsorption capacity and high photocatalytic ability. The enhanced photocatalytic activities may be related to the effects of the relatively high surface area, enhanced UV-light absorption, and decrease of charge carrier recombination resulting from the synergetic adsorption–photocatalytic degradation effect of ZnO and ACF. [ABSTRACT FROM AUTHOR]