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Viviane A. Klemmer Nupur Khera Barbara M. Siegenthaler Indranil Bhattacharya Franz E. Weber Chafik Ghayor 《International journal of molecular sciences》2021,22(20)
The human skeleton is a dynamic and remarkably organized organ system that provides mechanical support and performs a variety of additional functions. Bone tissue undergoes constant remodeling; an essential process to adapt architecture/resistance to growth and mechanical needs, but also to repair fractures and micro-damages. Despite bone’s ability to heal spontaneously, certain situations require an additional stimulation of bone regeneration, such as non-union fractures or after tumor resection. Among the growth factors used to increase bone regeneration, bone morphogenetic protein-2 (BMP2) is certainly the best described and studied. If clinically used in high quantities, BMP2 is associated with various adverse events, including fibrosis, overshooting bone formation, induction of inflammation and swelling. In previous studies, we have shown that it was possible to reduce BMP2 doses significantly, by increasing the response and sensitivity to it with small molecules called “BMP2 enhancers”. In the present study, we investigated the effect of N-Vinyl-2-pyrrolidone (NVP) on osteoblast and osteoclast differentiation in vitro and guided bone regeneration in vivo. We showed that NVP increases BMP2-induced osteoblast differentiation and decreases RANKL-induced osteoclast differentiation in a dose-dependent manner. Moreover, in a rabbit calvarial defect model, the histomorphometric analysis revealed that bony bridging and bony regenerated area achieved with NVP-loaded poly (lactic-co-glycolic acid (PLGA) membranes were significantly higher compared to unloaded membranes. Taken together, our results suggest that NVP sensitizes BMP2-dependent pathways, enhances BMP2 effect, and inhibits osteoclast differentiation. Thus, NVP could prove useful as “osteopromotive substance” in situations where a high rate of bone regeneration is required, and in the management of bone diseases associated with excessive bone resorption, like osteoporosis. 相似文献
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Mercedes P Geimba Alessandro Riffel Viviane Agostini Adriano Brandelli 《Journal of the science of food and agriculture》1999,79(13):1849-1854
Cellulose-hydrolysing enzymes from the phytopathogenic fungus Bipolaris sorokiniana were partially purified and characterised. The enzyme production was variable according to the carbon source. β-Glucosidase and cellobiohydrolase activities were higher by growing the fungus on cellulose than on other carbon sources. Carboxymethyl cellulase production was stimulated by other carbohydrates, mainly lactose. Partial enzyme purification was carried out by liquid chromatography on Sepharose CL4B. The purification was about 17-fold, with a yield of 41% as judged by assay with p-nitrophenyl-β-D -glucopyranoside as substrate. The optimum pH and temperature were 5.0 and 55–60 °C respectively. The enzyme was stable at 28 and 37 °C but lost about 50% of its initial activity after 120 min at 55 °C. Saccharification of cellulosic materials such as crystalline cellulose, filter paper and wheat straws was carried out using the partially purified enzyme, resulting in the production of reducing sugars. © 1999 Society of Chemical Industry 相似文献
55.
G. Weber E. Sciora J. Guichard F. Bouyer I. Bezverkhyy F. Bernard H. Lecoq R. Besnard J.-P. Bellat 《International Journal of Hydrogen Energy》2018,43(50):22557-22567
The reaction of lithium hydride (LiH) powder with pure water vapor (H2O and D2O) was studied by thermogravimetry and in situ infrared spectroscopy at 298 K over a large pressure range. The mean particle size of LiH is around 27 μm. At very low pressure, the hydrolysis starts with the formation of lithium oxide (Li2O). Then, both Li2O and lithium hydroxide (LiOH) are formed on increasing pressure, thus, creating a Li2O/LiOH bilayer. The reaction takes place through the consumption of LiH and the formation of Li2O at the LiH/Li2O interface and through the consumption of Li2O and the formation of LiOH at the Li2O/LiOH interface. Above 10 hPa, only the monohydrate LiOH·H2O is formed. This hydration reaction of LiOH into LiOH·H2O occurs at a lower pressure (8 hPa) after the first hydration-dehydration cycle. The hydrolysis mechanism proposed in this paper suggests that the diffusion of ionic species across the intermediate Li2O layer is the rate limiting step of the reaction. 相似文献
56.
Miguel Afonso Sellitto Giancarlo Medeiros Pereira Miriam Borchardt Rosnaldo Inácio da Silva Cláudia Viviane Viegas 《国际生产研究杂志》2013,51(16):4917-4926
Supply Chain Operations Reference (SCOR) is a widely employed model for SC performance assessment, regardless its generic nature. This article presents a SCOR-based model for performance measurement in supply chains (SC) and apply it in the context of Brazilian footwear industry. The model has two dimensions: SCOR processes (source, make, deliver and return) and performance standards adapted from original SCOR (cost, quality, delivery and flexibility). This structure delivers a 4 × 4 matrix, with each component assessed under analytical hierarchy process. Using focus groups, SC’s experts weighted each component of the matrix regarding their relevance. Thereafter, SC’s managers indicated respective results. The SC’s overall performance was obtained by adding the performance of all indicators. The model application embraced one focal footwear manufacturer, four suppliers, three distribution channels and a return channel, with 85 indicators assessed. The achieved performance for the whole SC is 75.29%.The main gaps were found in deliver process (12.78 percentual points of difference between relevance and achieved proportions) and in flexibility performance (9.82). Further application is recommended in order to find consolidated results. 相似文献
57.
Viviane?L.?Pardo Cássia?A.?M.?Fagundes Sergiane?S.?Caldas Márcia?H.?Kurz Rosilene?M.?Clementin Marcelo?G.?M.?D’Oca Ednei?G.?PrimelEmail author 《Journal of the American Oil Chemists' Society》2012,89(4):631-637
The aim of this study was to develop and validate a method for the analysis of fatty acid methyl ester (FAMEs) content in
tung biodiesel and blends with soybean biodiesel. The limits of detection (LOD) and quantification (LOQ), linearity, robustness,
accuracy and precision were evaluated by using gas chromatography with mass spectrometry detection and impact electron ionization.
The analytical curves showed correlation coefficients values higher than 0.99. The LOD and LOQ were 0.78 and 2.5 mg L−1 for all FAMEs, respectively. The values of accuracy were between 86 and 117%, with relative standard deviation lower than
8%. The method was applied to tung biodiesel and tung and soybean biodiesel blends in the following proportions: 15:85, 20:80,
25:75 (%v/v). All of them showed good performance. Since the method was also applied to soybean biodiesel, the efficiency
of the method for the analysis of both pure tung biodiesel and blends with different raw materials was confirmed and the robustness
of the method was evidenced. 相似文献
58.
Stamatina N. Vouyiouka Viviane Filgueiras Constantine D. Papaspyrides Enrique L. Lima Jose Carlos Pinto 《应用聚合物科学杂志》2012,124(6):4457-4465
Poly(ethylene terephthalate‐co‐isophthalate) (PETI) prepolymer was submitted to solid state polymerization (SSP) at 184–230°C in a fixed bed reactor, to study the evolution of morphological changes during the process. Short reaction times were selected to investigate crystallization phenomena during nonisothermal (heating) and isothermal SSP phases. More specifically, multiple PETI melting behavior was observed and attributed to secondary crystallization, the rate of which increased significantly with SSP temperature. Reaction time was also found to exert a positive effect on solid‐phase perfection of secondary crystals, leading at each temperature to melting points close to the value of bottle‐grade poly(ethylene terephthalate). Finally, the mass fraction crystallinity of the SSP grades was found to comply with the crystal morphology encountered. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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Viviane Trevisan Luiz Olinto Monteggia Henrique dos Santos Delabary 《International Journal of Hydrogen Energy》2014
A short-term test (time interval < 24 h) is proposed to evaluate the concentration of organic matter from industrial effluents for the production of hydrogen. Organic substrates selected were: protein effluent from a soybean processing plant; glycerol, from the production of biodiesel; Tebuconazole, a fungicide; and glucose, used as a reference substrate. Volatile fatty acids (VFA) and the degree of acidification of each substrate are also determined. After glucose (average hydrogen release of 24.8 mL g COD−1), protein effluent provided the highest hydrogen yield (1.74 mL g COD−1). Acetic and butyric acids presented the highest VFA concentrations. Fermentation of Tebuconazole presented the highest degree of acidification. Some considerations are made about the biological processes involved in hydrogen production. 相似文献