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151.
Sara Salucci Michela Battistelli Sabrina Burattini Cesare Squillace Barbara Canonico Pietro Gobbi Stefano Papa Elisabetta Falcieri 《Micron (Oxford, England : 1993)》2010,41(8):966-973
Apoptosis is a form of cell death crucial for normal development and tissue homeostasis. Its typical features include chromatin changes, nuclear breakdown, plasma membrane blebbing and splitting of cellular content into apoptotic bodies, that progressively undergo phagocytosis.Apoptosis is considered essential for skeletal muscle development, where defective cells are deleted during differentiation. In addition, it plays a relevant role in several muscle myopathies, as well as in denervation and disuse.The aim of this study was to evaluate muscle cell sensitivity to different apoptotic triggers, acting through different mechanisms of action. Chemical agents, active against distinct intracellular targets, such as mitochondrial respiratory chain and DNA, have been chosen to better highlight cell death mechanisms. To induce apoptosis, C2C12 myoblasts have been exposed to H2O2, staurosporine, cisplatin and etoposide, at different doses and incubation times, and they have been analysed by flow cytometry, scanning and transmission electron microscopy.Flow cytometry analysis revealed a certain subdiploid peak after all treatments. The best apoptotic effect was observable, as confirmed at reverted microscope, at minimum doses and after the major exposure time.At ultrastructural level programmed cell death has been observed. Characteristic chromatin condensation and margination, as well as apoptotic bodies, frequently appeared, even if in the presence of secondary necrosis; surface blebs were also observed during scanning microscopic observation.In particular, exposure to H2O2 or staurosporine showed the largest number of myoblasts in late apoptotic stages and in secondary necrosis. Cisplatin treatments revealed few early apoptotic cells. The analysis of etoposide-induced apoptosis was in agreement with data obtained from flow cytometry, indicating a significant increase of apoptotic cell number.These results suggest that all conditions are able to induce apoptosis in C2C12 myoblasts, which occurs, considering trigger mechanisms of action, mostly following the mitochondrial pathway, if not excluding that due to DNA damage. Therefore, mitochondria permeability alteration is an important step in skeletal muscle programmed cell death. This last conclusion seems to have a significant relevance in understanding the mechanisms involved in muscle disorders, denervation and chronic muscle disuse, conditions frequently characterized by a decline in mitochondrial content and by an increase of mitochondrial apoptosis susceptibility. 相似文献
152.
Pietro Baldi Emanuele Haus Riccardo Montalto 《Journal of Differential Equations》2018,264(3):1786-1840
We prove internal controllability in arbitrary time, for small data, for quasi-linear Hamiltonian NLS equations on the circle. We use a procedure of reduction to constant coefficients up to order zero and HUM method to prove the controllability of the linearized problem. Then we apply a Nash–Moser–Hörmander implicit function theorem as a black box. 相似文献
153.
Numerical Algorithms - The Alternating Direction Multipliers Method (ADMM) is a very popular algorithm for computing the solution of convex constrained minimization problems. Such problems are... 相似文献
154.
A bounded operator defined on a Banach space is said to be polaroid if every isolated point of the spectrum is a pole of the
resolvent. In this paper we consider the two related notions of left and right polaroid, and explore them together with the
condition of being a-polaroid. Moreover, the equivalences of Weyl type theorems and generalized Weyl type theorems are investigated for left and
a-polaroid operators. As a consequence, we obtain a general framework which allows us to derive in a unified way many recent
results, concerning Weyl type theorems (generalized or not) for important classes of operators. 相似文献
155.
156.
Patrizia Berti Luca Pratelli Pietro Rigo 《Probability Theory and Related Fields》2010,148(1-2):269-283
Let ${(\Omega, \mathcal{F}, P)}$ be a probability space. For each ${\mathcal{G}\subset\mathcal{F}}$ , define ${\overline{\mathcal{G}}}$ as the σ-field generated by ${\mathcal{G}}$ and those sets ${F\in \mathcal{F}}$ satisfying ${P(F)\in\{0,1\}}$ . Conditions for P to be atomic on ${\cap_{i=1}^k\overline{\mathcal{A}_i}}$ , with ${\mathcal{A }_1,\ldots,\mathcal{A}_k\subset\mathcal{F}}$ sub-σ-fields, are given. Conditions for P to be 0-1-valued on ${\cap_{i=1}^k \overline{\mathcal{A}_i}}$ are given as well. These conditions are useful in various fields, including Gibbs sampling, iterated conditional expectations and the intersection property. 相似文献
157.
158.
Alberto Sapora Pietro Cornetti Alberto Carpinteri 《Communications in Nonlinear Science & Numerical Simulation》2013,18(1):63-74
In the present paper, the wave propagation in one-dimensional elastic continua, characterized by nonlocal interactions modeled by fractional calculus, is investigated. Spatial derivatives of non-integer order 1 < α < 2 are involved in the governing equation, which is solved by fractional finite differences. The influence of long-range interactions is then analyzed as α varies: the resonant frequencies and the standing waves of a nonlocal bar are evaluated and the deviations from the classical (local) ones, recovered by imposing α = 2, are discussed. 相似文献
159.
Weyl type theorems have been proved for a considerably large number of classes of operators. In this paper, by introducing the class of quasi totally hereditarily normaloid operators, we obtain a theoretical and general framework from which Weyl type theorems may be promptly established for many of these classes of operators. This framework also entails Weyl type theorems for perturbations f(T + K), where K is algebraic and commutes with T, and f is an analytic function, defined on an open neighborhood of the spectrum of T + K, such that f is non constant on each of the components of its domain. 相似文献
160.
Birarda Giovanni Delneri Ambra Lagatolla Cristina Parisse Pietro Cescutti Paola Vaccari Lisa Rizzo Roberto 《Analytical and bioanalytical chemistry》2019,411(27):7315-7325
Analytical and Bioanalytical Chemistry - Biofilms are communities of bacteria living embedded in a highly hydrated matrix composed of polysaccharides, proteins, and extracellular DNA. This life... 相似文献