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131.
Gentile A Toietta G Pazzano V Tsiopoulos VD Giglio AF Crea F Pompilio G Capogrossi MC Di Rocco G 《Molecular biology of the cell》2011,22(5):581-592
Recent studies have underscored a role for the epicardium as a source of multipotent cells. Here, we investigate the myogenic potential of adult human epicardium-derived cells (EPDCs) and analyze their ability to undergo skeletal myogenesis when cultured with differentiating primary myoblasts. Results are compared to those obtained with mesenchymal stromal cells (MSCs) and with endothelial cells, another mesodermal derivative. We demonstrate that EPDCs spontaneously fuse with pre-existing myotubes with an efficiency that is significantly higher than that of other cells. Although at a low frequency, endothelial cells may also contribute to myotube formation. In all cases analyzed, after entering the myotube, nonmuscle nuclei are reprogrammed to express muscle-specific genes. The fusion competence of nonmyogenic cells in vitro parallels their ability to reconstitute dystrophin expression in mdx mice. We additionally show that vascular cell adhesion molecule 1 (VCAM1) expression levels of nonmuscle cells are modulated by soluble factors secreted by skeletal myoblasts and that VCAM1 function is required for fusion to occur. Finally, treatment with interleukin (IL)-4 or IL-13, two cytokines released by differentiating myotubes, increases VCAM1 expression and enhances the rate of fusion of EPDCs and MSCs, but not that of endothelial cells. 相似文献
132.
Maria De Santis Rosanna Inzitari Silvia L Bosello Giusy Peluso Chiara Fanali Federica Iavarone Gaetano Zizzo Mario Bocci Tiziana Cabras Irene Messana Leo Fuso Francesco Varone Gabriella Pagliari Massimo Castagnola Gianfranco Ferraccioli 《Respiratory research》2011,12(1):22
Background
β-thymosins play roles in cytoskeleton rearrangement, angiogenesis, fibrosis and reparative process, thus suggesting a possible involvement in the pathogenesis of systemic sclerosis. The aim of the study was to investigate the presence of thymosins β4, β4 sulfoxide, and β10 in bronchoalveolar lavage fluid of scleroderma patients with interstitial lung disease and the relation of these factors with pulmonary functional and radiological parameters.Methods
β-thymosins concentrations were determined by Reverse Phase-High Performance Liquid Chromatography-Electrospray-Mass Spectrometry in the bronchoalveolar lavage fluid of 46 scleroderma patients with lung involvement and of 15 controls.Results
Thymosin β4, β4 sulfoxide, and β10 were detectable in bronchoalveolar lavage fluid of patients and controls. Thymosin β4 levels were significantly higher in scleroderma patients than in controls. In addition, analyzing the progression of scleroderma lung disease at one-year follow-up, we have found that higher thymosin β4 levels seem to have a protective role against lung tissue damage. Thymosin β4 sulfoxide levels were higher in the smokers and in the scleroderma patients with alveolitis.Conclusions
We describe for the first time β-thymosins in bronchoalveolar lavage fluid and their possible involvement in the pathogenesis of scleroderma lung disease. Thymosin β4 seems to have a protective role against lung tissue damage, while its oxidation product mirrors an alveolar inflammatory status. 相似文献133.
Simeone L Mangiapia G Irace C Di Pascale A Colonna A Ortona O De Napoli L Montesarchio D Paduano L 《Molecular bioSystems》2011,7(11):3075-3086
Novel thymidine- or uridine-based nucleolipids, containing one hydrophilic oligo(ethylene glycol) chain and one or two oleic acid residues (called ToThy, HoThy and DoHu), have been synthesized with the aim to develop bio-compatible nanocarriers for drug delivery and/or produce pro-drugs. Microstructural characterization of their aggregates has been determined in pure water and in pseudo-physiological conditions through DLS and SANS experiments. In all cases stable vesicles, with mean hydrodynamic radii ranging between 120 nm and 250 nm have been revealed. Biological validation of the nucleolipidic nanocarriers was ensured by evaluation of their toxicological profiles, performed by administration of the nanoaggregates to a panel of different cell lines. ToThy exhibited a weak cytotoxicity and, at high concentration, some ability to interfere with cell viability and/or proliferation. In contrast, DoHu and HoThy exhibited no toxicological relevance, behaving similarly to POPC-based liposomes, widely used for systemic drug delivery. Taken together, these results show nucleolipid-based nanocarriers as finely tunable, multi-functional self-assembling materials of interest for the in vivo transport of biomolecules or drugs. 相似文献
134.
Rocco Barazzoni 《e》2011,6(3):e158-e164
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A brown alga of the genus Dictyota has yielded three new dolabellane diterpenoids the structures of which were elucidated mainly by spectroscopic methods. 相似文献
139.
Gaetano Granozzi Renzo Benoni Mario Acampora Silvio Aime Domencio Osella 《Inorganica chimica acta》1984,84(1):95-100
The electronic structure of H2M3(CO)9S clusters (M = Ru, Os) is discussed on the basis of their He I and He II excited gas-phase photoelectron spectra and on the basis of CNDO quantum mechanical calculations. The PE data clearly demonstrate the cleavage of two direct MM interactions by operation of the bridging hydrides, giving rise to three-center two-electron MHM levels. The μ3-S bonding mode has been described in detail and compared with previous results on related μ3-CY cluster derivatives. The CNDO results on Ru3(CO)9S=, HRu3(CO)9S? and H2Ru3(CO)9S indicate that the μ3-S—cluster interaction is mostly independent of the presence of the bridging hydrides. 相似文献
140.
Panunzi S De Gaetano A Mingrone G 《American journal of physiology. Endocrinology and metabolism》2005,289(5):E915-E922
Dicarboxylic acids with an even number of carbon atoms have been proposed as an alternate energy substrate for enteral or parenteral nutrition in the acutely ill patient, due to their water solubility and their yielding TCA cycle intermediates upon beta-oxidation. In the present work, a nonlinear compartmental model of the kinetics of dodecanedioic acid is developed, and its parameters are estimated from time concentration experimental observations obtained from six healthy volunteers undergoing a per os administration of 3 g of the substance. Although the model is linear in the transfer of the free substance from plasma to the tissues, the exchange between gut and plasma compartments is represented as a saturable function. Albumin binding is then incorporated to obtain the final model in terms of the measured total concentrations. Estimates of the model's structural parameters were computed for each experimental subject, and the usual single-subject approximate confidence regions for the parameters were derived by inversion of the Hessian at the optimum. To verify the applicability of this approximation, the nonlinearity of the expectation surface at the optimum was measured by computing the normal (intrinsic) component of curvature. Because the model curvature was excessive in all subjects, the usual approximation could not be trusted to provide acceptable approximations to the parameter confidence regions. A suitable Monte Carlo simulation yielded empirical joint parameter distributions from which the approximate parameter variances could finally be obtained. 相似文献