22 research outputs found

    Naturally occurring diacetyl and 2,3-pentanedione concentrations associated with roasting and grinding unflavored coffee beans in a commercial setting

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    AbstractOver the last decade, concerns have been raised about potential respiratory health effects associated with occupational exposure to the flavoring additives diacetyl and 2,3-pentanedione. Both of these diketones are also natural components of many foods and beverages, including roasted coffee. To date, there are no published studies characterizing workplace exposures to these diketones during commercial roasting and grinding of unflavored coffee beans. In this study, we measured naturally occurring diacetyl, 2,3-pentanedione, and respirable dust at a facility that roasts and grinds coffee beans with no added flavoring agents. Sampling was conducted over the course of three roasting batches and three grinding batches at varying distances from a commercial roaster and grinder. The three batches consisted of lightly roasted soft beans, lightly roasted hard beans, and dark roasted hard beans. Roasting occurred for 37 to 41min, and the grinding process took between 8 and 11min. Diacetyl, 2,3-pentanedione, and respirable dust concentrations measured during roasting ranged from less than the limit of detection (<LOD) to 0.0039ppm, <LOD to 0.018ppm, and <LOD to 0.31mg/m3, respectively. During grinding, diacetyl, 2,3-pentanedione, and respirable dust concentrations ranged from 0.018 to 0.39ppm, 0.0089 to 0.21ppm, and <LOD to 1.7mg/m3, respectively. For any given bean/roast combination and sample location, diketone concentrations during grinding were higher than those measured during roasting. During grinding, concentrations decreased with increased distance from the source. Measured concentrations of both diketones were higher during grinding of soft beans than hard beans. The results indicate that airborne concentrations of naturally occurring diacetyl and 2,3-pentanedione associated with unflavored coffee processing: (1) are similar to the concentrations that have been measured in food flavoring facilities; (2) are likely to exceed some recommended short-term occupational exposure limits, but; (3) based on previous analyses of exposure response relationships in animal studies, are far below the concentrations that are expected to cause even minimal responses in the human respiratory tract

    An ex vivo human tumour assay reveals distinct patterns of EGFR trafficking in squamous cell carcinoma correlating to therapeutic outcomes

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    EGFR overexpression is associated with squamous cell carcinoma development. Altered endocytosis and polarization of receptor tyrosine kinases, including EGFR, affect migration and invasion in 3D culture. These studies have been completed via genetic sequencing, cell line or 3D in vitro and in vivo murine models. Here we describe an imaging method that allows ex-vivo examination of ligand-induced endocytosis of EGFR in non-dissociated human tumours. We analyzed sets of tumour samples from advanced cutaneous squamous cell carcinoma and Head and Neck squamous cell carcinoma, actinic keratosis, intra-epidermal carcinoma and cutaneous squamous cell carcinoma. We demonstrate that EGFR endocytosis is dysregulated in advanced SCC and correlates with anti-EGFR monoclonal antibody therapy outcomes. In actinic keratosis, intra-epidermal carcinoma and well-differentiated cutaneous squamous cell carcinoma different patterns of epidermal growth factor ligand uptake and binding were observed at the leading edge of different dysplastic lesions, suggesting that these differences in EGFR endocytosis might influence the metastatic potential of dysplastic squamous epithelium. These studies in live ex-vivo human tumours confirm that endocytosis dysregulation is a physiological event in human tumours and has therapeutic implications

    Optimizing Combination Therapies with Existing and Future CML Drugs

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    Small-molecule inhibitors imatinib, dasatinib and nilotinib have been developed to treat Chromic Myeloid Leukemia (CML). The existence of a triple-cross-resistant mutation, T315I, has been a challenging problem, which can be overcome by finding new inhibitors. Many new compounds active against T315I mutants are now at different stages of development. In this paper we develop an algorithm which can weigh different combination treatment protocols according to their cross-resistance properties, and find the protocols with the highest probability of treatment success. This algorithm also takes into account drug toxicity by minimizing the number of drugs used, and their concentration. Although our methodology is based on a stochastic model of CML microevolution, the algorithm itself does not require measurements of any parameters (such as mutation rates, or division/death rates of cells), and can be used by medical professionals without a mathematical background. For illustration, we apply this algorithm to the mutation data obtained in [1], [2]

    Improved functionalization of oleic acid-coated iron oxide nanoparticles for biomedical applications

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    Superparamagnetic iron oxide nanoparticles can providemultiple benefits for biomedical applications in aqueous environments such asmagnetic separation or magnetic resonance imaging. To increase the colloidal stability and allow subsequent reactions, the introduction of hydrophilic functional groups onto the particles’ surface is essential. During this process, the original coating is exchanged by preferably covalently bonded ligands such as trialkoxysilanes. The duration of the silane exchange reaction, which commonly takes more than 24 h, is an important drawback for this approach. In this paper, we present a novel method, which introduces ultrasonication as an energy source to dramatically accelerate this process, resulting in high-quality waterdispersible nanoparticles around 10 nmin size. To prove the generic character, different functional groups were introduced on the surface including polyethylene glycol chains, carboxylic acid, amine, and thiol groups. Their colloidal stability in various aqueous buffer solutions as well as human plasma and serum was investigated to allow implementation in biomedical and sensing applications.status: publishe

    Supplementary dataset for child and adult exposure and health risk evaluation following the use of metal- and metalloid-containing costume cosmetics sold in the United States

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    The data presented in this article are related to the research article entitled ''Child and adult exposure and health risk evaluation following the use of metal- and metalloid-containing costume cosmetics sold in the United States'' [1]. This article describes the concentration of metals and metalloids contained in various cosmetic products such as body paint, lipstick and eye shadow, the relative percent deviation of two analyses performed on the products and the physico-chemico properties of the metals and metalloids used in the SkinPerm model presented in the aforementioned article. Keywords: Cosmetics, Makeup, Halloween, Metal, Metalloid, Lead, Arsenic, Face paint, Body pain
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