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941.
Alessandra Cazzaniga Fabian Ille Simon Wuest Carsten Haack Adrian Koller Christina Giger-Lange Monica Zocchi Marcel Egli Sara Castiglioni Jeanette A. Maier 《International journal of molecular sciences》2020,21(23)
We introduce a new benchtop microgravity simulator (MGS) that is scalable and easy to use. Its working principle is similar to that of random positioning machines (RPM), commonly used in research laboratories and regarded as one of the gold standards for simulating microgravity. The improvement of the MGS concerns mainly the algorithms controlling the movements of the samples and the design that, for the first time, guarantees equal treatment of all the culture flasks undergoing simulated microgravity. Qualification and validation tests of the new device were conducted with human bone marrow stem cells (bMSC) and mouse skeletal muscle myoblasts (C2C12). bMSC were cultured for 4 days on the MGS and the RPM in parallel. In the presence of osteogenic medium, an overexpression of osteogenic markers was detected in the samples from both devices. Similarly, C2C12 cells were maintained for 4 days on the MGS and the rotating wall vessel (RWV) device, another widely used microgravity simulator. Significant downregulation of myogenesis markers was observed in gravitationally unloaded cells. Therefore, similar results can be obtained regardless of the used simulated microgravity devices, namely MGS, RPM, or RWV. The newly developed MGS device thus offers easy and reliable long-term cell culture possibilities under simulated microgravity conditions. Currently, upgrades are in progress to allow real-time monitoring of the culture media and liquids exchange while running. This is of particular interest for long-term cultivation, needed for tissue engineering applications. Tissue grown under real or simulated microgravity has specific features, such as growth in three-dimensions (3D). Growth in weightlessness conditions fosters mechanical, structural, and chemical interactions between cells and the extracellular matrix in any direction. 相似文献
942.
Monica Frinchi Vincenzo Verdi Fulvio Plescia Francisco Ciruela Maria Grillo Roberta Garozzo Daniele F. Condorelli Patrizia Di Iorio Francesco Caciagli Renata Ciccarelli Natale Belluardo Valentina Di Liberto Giuseppa Mud 《International journal of molecular sciences》2020,21(23)
Acute or chronic administration of guanosine (GUO) induces anxiolytic-like effects, for which the adenosine (ADO) system involvement has been postulated yet without a direct experimental evidence. Thus, we aimed to investigate whether adenosine receptors (ARs) are involved in the GUO-mediated anxiolytic-like effect, evaluated by three anxiety-related paradigms in rats. First, we confirmed that acute treatment with GUO exerts an anxiolytic-like effect. Subsequently, we investigated the effects of pretreatment with ADO or A1R (CPA, CCPA) or A2AR (CGS21680) agonists 10 min prior to GUO on a GUO-induced anxiolytic-like effect. All the combined treatments blocked the GUO anxiolytic-like effect, whereas when administered alone, each compound was ineffective as compared to the control group. Interestingly, the pretreatment with nonselective antagonist caffeine or selective A1R (DPCPX) or A2AR (ZM241385) antagonists did not modify the GUO-induced anxiolytic-like effect. Finally, binding assay performed in hippocampal membranes showed that [3H]GUO binding became saturable at 100–300 nM, suggesting the existence of a putative GUO binding site. In competition experiments, ADO showed a potency order similar to GUO in displacing [3H]GUO binding, whereas AR selective agonists, CPA and CGS21680, partially displaced [3H]GUO binding, but the sum of the two effects was able to displace [3H]GUO binding to the same extent of ADO alone. Overall, our results strengthen previous data supporting GUO-mediated anxiolytic-like effects, add new evidence that these effects are blocked by A1R and A2AR agonists and pave, although they do not elucidate the mechanism of GUO and ADO receptor interaction, for a better characterization of GUO binding sites in ARs. 相似文献
943.
Ciofani G Ricotti L Rigosa J Menciassi A Mattoli V Monici M 《Journal of Bioscience and Bioengineering》2012,113(2):258-261
This study aimed at the investigation of behavior of myoblasts in conditions of altered gravity. C2C12 cells underwent stimulations by different hypergravity intensities (2 h at 5 g, 10 g, and 20 g) in the Large Diameter Centrifuge of the European Space Agency (ESA), highlighting positive effects on both proliferation and differentiation. 相似文献
944.
Composite films of plasticized potato starch filled with 1, 4, and 6 wt% zirconium phosphate (ZrP) particles have been prepared by casting mixtures of gelatinized starch, a gel of partially exfoliated ZrP in water, and glycerol. The XRD patterns of the composite films reveal the formation of glycerol intercalated ZrP for the highest filler loadings (4 and 6 wt%) while suggest partial filler exfoliation for the composite with 1 wt% ZrP, in agreement with TEM analysis. The presence of the filler improves the thermal resistance of the starch, both at low and, particularly, at high temperature. The composites also exhibit a significant enhancement in the Young's modulus (from ∼700 MPa for neat starch up to ∼1600 MPa for 6 wt% filler loading) and in the yield stress (from ∼17 to ∼38 MPa). The increase in stiffness is concomitant with a water uptake reduction, which is maximum at 100% relative humidity. 相似文献
945.
Bourdichon F Casaregola S Farrokh C Frisvad JC Gerds ML Hammes WP Harnett J Huys G Laulund S Ouwehand A Powell IB Prajapati JB Seto Y Ter Schure E Van Boven A Vankerckhoven V Zgoda A Tuijtelaars S Hansen EB 《International journal of food microbiology》2012,154(3):87-97
Microbial food cultures have directly or indirectly come under various regulatory frameworks in the course of the last decades. Several of those regulatory frameworks put emphasis on "the history of use", "traditional food", or "general recognition of safety". Authoritative lists of microorganisms with a documented use in food have therefore come into high demand. One such list was published in 2002 as a result of a joint project between the International Dairy Federation (IDF) and the European Food and Feed Cultures Association (EFFCA). The "2002 IDF inventory" has become a de facto reference for food cultures in practical use. However, as the focus mainly was on commercially available dairy cultures, there was an unmet need for a list with a wider scope. We present an updated inventory of microorganisms used in food fermentations covering a wide range of food matrices (dairy, meat, fish, vegetables, legumes, cereals, beverages, and vinegar). We have also reviewed and updated the taxonomy of the microorganisms used in food fermentations in order to bring the taxonomy in agreement with the current standing in nomenclature. 相似文献
946.
Jean Daniel Coïsson Marco Arlorio Monica Locatelli Cristiano Garino Donatella Resta Elena Sirtori Anna Arnoldi Giovanna Boschin 《Food chemistry》2011
A chemotyping and genotyping comprehensive approach may be useful for the analytical traceability of food ingredients. The interest for lupin (Lupinus spp.) is developing owing to the high protein percentage as well as the positive technological and nutraceutical properties. The objective was the development of innovative models for discerning between Lupinus albus and Lupinus angustifolius, the most used in human nutrition, by applying multivariate statistical analysis (Principal Component Analysis, PCA) and artificial intelligence (Self Organising Maps, SOMs) onto chemical parameters (proximate composition, alkaloids, tocopherols) or Random Polymorphic DNA fingerprints. The application of PCA to either chemical or genetic data permitted the effective discrimination between the two species, whereas the application of the SOM approach to both data-sets enabled clustering some cultivars. The possibility of discriminating L. albus from L. angustifolius is relevant for lupin traceability: the foreseen fields of application are refined flours or ingredients, where morphological analysis is not applicable. 相似文献
947.
Four steroid hormones, namely androsterone, cholesterol, estrone and estradiol, have been pyrolysed at 300, 400 and 500 °C and the pyrolysates from these have been analysed by GC–MS. The results indicate that these formed different products under the pyrolysis and most of them evolved into polycyclic aromatic hydrocarbons during their residence in the pyrolysis chamber at high temperatures. The products from the pyrolysates, at all temperatures, were analysed for similarities and differences using multivariate data analysis. The products possessed some similarities on pyrolysis at 300 °C but were entirely different when pyrolysed at 500 °C. Androsterone and cholesterol formed a higher percentage of substituted PAH than did estrone and estradiol. These compounds included carcinogens, such as phenanthrene, methylphenanthrene, fluorene and its derivatives. The side chain of cholesterol had no effect on the products formed, while the presence of the aromatic ring in estrone and estradiol led to a higher percentage of phenol and its derivatives in the pyrolysates. Furthermore, estrone was subjected to flash pyrolysis and the products formed were compared with those which resulted from the long time pyrolysis: flash pyrolysis produced small amounts of PAH. 相似文献
948.
Tundis R Loizzo MR Bonesi M Menichini F Mastellone V Colica C Menichini F 《Journal of food science》2012,77(1):H40-H46
Abstract: The interest in medicinal plant research and in the aroma‐therapeutic effects of essential oils in humans has increased in recent years, especially for the treatment of pathologies of relevant social impact such as Alzheimer's disease. The present study was taken up to evaluate the antioxidant capacity and the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity of the peel essential oils from three Citrus species, C. aurantifolia Swingle, C. aurantium L., and C. bergamia Risso & Poit. Essential oils were analyzed by GC and GC‐MS and they contain mainly limonene, α‐pinene, β‐pinene, γ‐terpinene, and linalyl acetate. C. aurantifolia oil showed the highest radical scavenging activity on ABTS assay (IC50 value of 19.6 μg/mL), while C. bergamia exhibited a good antioxidant activity evaluated by the β‐carotene bleaching test (IC50= 42.6 μg/mL after 60 min of incubation). C. aurantifolia inhibited more selectively AChE. Obtained data suggest a potential use of Citrus oils as a valuable new flavor with functional properties for food or nutraceutical products with particular relevance to supplements for the elderly. Practical Application: The demonstrated antioxidant activity and procholinesterase properties of Citrus essential oils suggested their use as a new potential source of natural antioxidant to added as extra‐nutrient for using in food industries as a valuable new flavor with functional properties for food or nutraceutical products with particular relevance to supplements for the elderly. 相似文献
949.
Angie De La Cruz Aubrey Hargrave Sri Magadi Justin A. Courson Paul T. Landry Wanyu Zhang Fong W. Lam Monica A. Bray C. Wayne Smith Alan R. Burns Rolando E. Rumbaut 《International journal of molecular sciences》2021,22(14)
Platelet extravasation during inflammation is under-appreciated. In wild-type (WT) mice, a central corneal epithelial abrasion initiates neutrophil (PMN) and platelet extravasation from peripheral limbal venules. The same injury in mice expressing low levels of the β2-integrin, CD18 (CD18hypo mice) shows reduced platelet extravasation with PMN extravasation apparently unaffected. To better define the role of CD18 on platelet extravasation, we focused on two relevant cell types expressing CD18: PMNs and mast cells. Following corneal abrasion in WT mice, we observed not only extravasated PMNs and platelets but also extravasated erythrocytes (RBCs). Ultrastructural observations of engorged limbal venules showed platelets and RBCs passing through endothelial pores. In contrast, injured CD18hypo mice showed significantly less venule engorgement and markedly reduced platelet and RBC extravasation; mast cell degranulation was also reduced compared to WT mice. Corneal abrasion in mast cell-deficient (KitW-sh/W-sh) mice showed less venule engorgement, delayed PMN extravasation, reduced platelet and RBC extravasation and delayed wound healing compared to WT mice. Finally, antibody-induced depletion of circulating PMNs prior to corneal abrasion reduced mast cell degranulation, venule engorgement, and extravasation of PMNs, platelets, and RBCs. In summary, in the injured cornea, platelet and RBC extravasation depends on CD18, PMNs, and mast cell degranulation. 相似文献
950.
Lara Manzocco Monica Anese Stefania Marzona Nadia Innocente Corrado Lagazio Maria Cristina Nicoli 《Food chemistry》2013
S. Daniele hams were collected at different stages during dry-curing and submitted to magnetic resonance imaging (MRI) according to the acquisition Spin-Echo sequences T1 and T2. The intensity of the MR signals in the images of the Semimembranosus, Semitendinosus, Rectus femoris and Biceps femoris muscles of the hams was computed and expressed in grey levels. Muscles were also submitted to traditional analyses, including aw, soluble solids, sodium chloride, total and water soluble nitrogen. T1 and T2 MR signals well described the evolution of the phenomena occurring in the different muscles during dry-curing. MR signal acquired in T2 mode well correlated with traditional indicators in Semitendinosus, Rectus femoris and Biceps femoris muscles. Predictive models estimating the value of aw, moisture, salt content and proteolysis extent on the basis of the MR signal intensity were proposed. 相似文献