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101.
Melatonin prevents mitochondrial dysfunctions and death in differentiated skeletal muscle cells
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Sara Salucci Michela Battistelli Valentina Baldassarri Debora Burini Elisabetta Falcieri Sabrina Burattini 《Microscopy research and technique》2017,80(11):1174-1181
Oxidative stress increase induces cellular damage and apoptosis activation, a mechanism believed to represent a final common pathway correlated to sarcopenia and many skeletal muscle disorders. The goal of this study is to evaluate if melatonin, a ROS scavenger molecule, is able to counteract or modulate myotube death. Here, differentiated C2C12 skeletal muscle cells have been treated with melatonin before chemicals known to induce apoptotic death and oxidative stress, and its effect has been investigated by means of morpho‐functional analyses. Ultrastructural observations show melatonin protection against triggers by the reducing of membrane blebbing, chromatin condensation, myonuclei loss and in situ DNA cleavage. Moreover, melatonin is able to prevent mitochondrial dysfunctions which occur in myotubes exposed to the trigger alone. These findings demonstrate melatonin ability in preventing apoptotic cell death in skeletal muscle fibers in vitro, suggesting for this molecule a potential therapeutic role in the treatment of various muscle disorders. 相似文献
102.
Yasuhiro Shimizu Elisabetta Di Bartolomeo Enrico Traversa Gualtiero Gusmano Takeo Hyodo Kenji Wada Makoto Egashira 《Sensors and actuators. B, Chemical》1999,60(2-3):118-124
NO2 sensing properties of SnO2-based varistor-type sensors have been investigated in the temperature range of 400-650°C and in the NO2 concentration range of 15–30 ppm. Pure SnO2 exhibited a weak nonlinear I–V characteristic in air, but clear nonlinearity in NO2 at 450°C. The breakdown voltage of SnO2 shifted to a high electric field upon exposure to NO2 and the magnitude of the shift was well correlated with NO2 concentration. Thus, SnO2 exhibited some sensitivity to NO2 as a varistor-type sensor. When SnO2 particles coated with a SiO2 thin film were used as a raw material for fabricating a varistor, the breakdown voltage in air was approximately the double that of pure SnO2 and the sensitivity to 15 ppm NO2 was enhanced slightly. However, the sensitivity to 30 ppm NO2 decreased. The Cr2O3-loading on SnO2 also led to an increase in the breakdown voltage in air, but the Cr2O3 addition was not effective for promoting the NO2 sensitivity under the present experimental conditions. 相似文献
103.
Antonio Arcadi Sabrina Di Giuseppe Fabio Marinelli Elisabetta Rossi 《Advanced Synthesis \u0026amp; Catalysis》2001,343(5):443-446
The gold(III)‐catalyzed sequential amination/annulation reaction of 2‐propynyl‐1,3‐dicarbonyl compounds 1 with primary amines 2 produces 1,2,3,5‐substituted pyrroles 4 in moderate to high yields. 相似文献
104.
Nerea de Miguel Beatriz Acosta P. Moretto Laurent Briottet Paolo Bortot Elisabetta Mecozzi 《International Journal of Hydrogen Energy》2017,42(19):13777-13788
This study investigates the fatigue life of CrMo pressure vessels for hydrogen storage by hydraulic and hydrogen pressure cycle tests. Two different sized cylinders have been tested; 35 L inner volume and 28 MPa working pressure (WP) and 198 L volume and 41 MPa WP. On the inner surface of the cylinders U-shaped notches of different depths were machined by electro discharge machining technique. The initial notch sizes were designed based on a two stage fatigue predictive model based on fracture mechanics to develop through wall cracks in the deepest notches after about 50,000 hydraulic cycles together with crack propagation of the intermediate notches and crack initiation in the smallest. The cylinders were cycled between the nominal pressure of 2 MPa and the WP until leak before break (LBB). Strain gauges were placed at the external surface of the cylinders in correspondence of the internally machined notches. On the notches which developed through wall, the strain showed a progressive decrease followed by an increase of the hoop strain during the final stage of crack propagation until LBB failure. Hydrogen effect was clearly identified by the reduction in the number of cycles to failure comparing tests in hydrogen and in oil. Subsequent failure analysis at the end of each test revealed a typical trans-granular fatigue crack surface morphology (with fatigue striations) for tests in oil, while quasi cleavage and intergranular fracture appearance were found for hydrogen tests. 相似文献
105.
Fiorella Sinesio Corrado Di Natale Giovanni B Quaglia Francesco M Bucarelli Elisabetta Moneta Antonella Macagnano Roberto Paolesse Arnaldo DAmico 《Journal of the science of food and agriculture》2000,80(1):63-71
In this paper the performances of an electronic nose based on metalloporphyrin‐coated quartz microbalance sensors and of an experienced panel of seven human assessors in the evaluation of gases derived from degradation reactions in tomatoes are presented and discussed. The performances are measured in terms of the capability of both systems to distinguish between samples of different quality coming from conventional and organic production systems. The study deals with the application of pattern recognition techniques based on either multivariate statistical methods (PCA, GPA) or artificial neural networks using a self‐organising map (SOM). The response pattern of the sensor array and the sensory data are analysed and compared using these methods. Similarities in the classification of the data by electronic nose and human sensory profiling are found. © 2000 Society of Chemical Industry 相似文献
106.
Maria Grazia Tupone Gloria Panella Michele dAngelo Vanessa Castelli Giulia Caioni Mariano Catanesi Elisabetta Benedetti Annamaria Cimini 《International journal of molecular sciences》2021,22(23)
Thanks to their reduced size, great surface area, and capacity to interact with cells and tissues, nanomaterials present some attractive biological and chemical characteristics with potential uses in the field of biomedical applications. In this context, graphene and its chemical derivatives have been extensively used in many biomedical research areas from drug delivery to bioelectronics and tissue engineering. Graphene-based nanomaterials show excellent optical, mechanical, and biological properties. They can be used as a substrate in the field of tissue engineering due to their conductivity, allowing to study, and educate neural connections, and guide neural growth and differentiation; thus, graphene-based nanomaterials represent an emerging aspect in regenerative medicine. Moreover, there is now an urgent need to develop multifunctional and functionalized nanomaterials able to arrive at neuronal cells through the blood-brain barrier, to manage a specific drug delivery system. In this review, we will focus on the recent applications of graphene-based nanomaterials in vitro and in vivo, also combining graphene with other smart materials to achieve the best benefits in the fields of nervous tissue engineering and neural regenerative medicine. We will then highlight the potential use of these graphene-based materials to construct graphene 3D scaffolds able to stimulate neural growth and regeneration in vivo for clinical applications. 相似文献
107.
Alessandra Feraco Stefania Gorini Andrea Armani Elisabetta Camajani Manfredi Rizzo Massimiliano Caprio 《International journal of molecular sciences》2021,22(17)
Skeletal muscle is essential to maintain vital functions such as movement, breathing, and thermogenesis, and it is now recognized as an endocrine organ. Muscles release factors named myokines, which can regulate several physiological processes. Moreover, skeletal muscle is particularly important in maintaining body homeostasis, since it is responsible for more than 75% of all insulin-mediated glucose disposal. Alterations of skeletal muscle differentiation and function, with subsequent dysfunctional expression and secretion of myokines, play a key role in the pathogenesis of obesity, type 2 diabetes, and other metabolic diseases, finally leading to cardiometabolic complications. Hence, a deeper understanding of the molecular mechanisms regulating skeletal muscle function related to energy metabolism is critical for novel strategies to treat and prevent insulin resistance and its cardiometabolic complications. This review will be focused on both cellular and animal models currently available for exploring skeletal muscle metabolism and endocrine function. 相似文献
108.
The natural microflora of cold-smoked fish at the end of shelf-life are lactic acid bacteria (LAB). Some of these display a capacity to inhibit spoilage as well as several strains of pathogenic micro-organisms, e.g. Listeria monocytogenes which is isolated frequently from cold-smoked salmon (CSS). Eight batches of sliced vacuum-packed CSS from Norway, Scotland and Spain were collected at retail. Packs were stored at 5 degrees C and examined for chemical and microbiological characteristics, at purchase date and at expiration date. pH, water activity and salt content were similar to available data on lightly preserved fish products. There was a consistent pattern in the development of the microflora on CSS; the initial level of LAB was low on freshly produced CSS (10(2) cfu g(-1)); however, storage in vacuum packaging at refrigeration temperature was elective for LAB. At the end of the stated shelf-life these micro-organisms, represented mainly by Lactobacillus spp., attained ca.10(7) cfu g(-1) while Enterobacteriaceae counts were consistently lower (10(5) cfu g(-1)), which indicates the ability of LAB to grow and compete with few carbohydrates available and in the presence of moderate salt concentrations. L. monocytogenes was not found in any sample. Forty-one percent of LAB strains isolated exhibited inhibitory capacity against Listeria innocua, in a plate assay. A majority of the inhibitory effects were non-bacteriocinogenic, but nevertheless were very competitive cultures which may provide an additional hurdle for improved preservation by natural means. 相似文献
109.
Armellin S Brenna E Frigoli S Fronza G Fuganti C Mussida D 《Analytical chemistry》2006,78(9):3113-3117
Samples of methamphetamine, prepared according to the most common synthetic pathways, were submitted to natural-abundance 2H NMR spectroscopy. The deuterium content at the various sites of the molecule was found to depend on its synthetic history. The technique provides a chemical fingerprint of methamphetamine samples and can give hints to trace back the starting materials and the synthetic procedures. 相似文献
110.
Serpe L Guido M Canaparo R Muntoni E Cavalli R Panzanelli P Della Pepal C Bargoni A Mauro A Gasco MR Eandi M Zara GP 《Journal of nanoscience and nanotechnology》2006,6(9-10):3062-3069
The structure of both carrier and anticancer drug affects the intracellular fate of a transported drug. The study investigated in vitro intracellular accumulation and cytotoxic activity of doxorubicin-loaded solid lipid nanoparticles (SLN), doxorubicin in pegylated liposomes (Caelyx) and free doxorubicin. Intracellular doxorubicin levels and cytotoxic activity were determined by high performance liquid chromatography with fluorescence detection, and by the trypan blue dye exclusion assay, respectively. Doxorubicin-loaded SLN inhibited cell growth more strongly than either free or liposomal doxorubicin, in human colorectal adenocarcinoma, HT-29, retinoblastoma Y79, and glioblastoma U373 cell lines. The IC50 values for doxorubicin-loaded SLN were significantly lower after 24 h exposure than those for free doxorubicin in all cell lines; after 48 h exposure they were lower than those for liposomal doxorubicin in HT-29 and Y79 cells. The enhanced cytotoxic activity of doxorubicin-loaded SLN was associated with increased drug incorporation in cells: intracellular doxorubicin levels were significantly enhanced after exposure to drug-loaded SLN versus either free or liposomal drug. Rate of intracellular accumulation and cytotoxic activity also differed among different cell lines; in particular, cells of epithelial origin were found to be more sensitive to doxorubicin-loaded SLN. In conclusion, the greater sensitivity of HT-29, Y79, and U373 cells to doxorubicin-loaded SLN than to the other drug formulations may be due to the capability of the delivery system to enhance drug action, through a marked uptake and accumulation of SLN within the cell. 相似文献