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排序方式: 共有620条查询结果,搜索用时 15 毫秒
171.
Giulia Maria Camerino Jean-Fran?ois Desaphy Michela De Bellis Roberta Francesca Capogrosso Anna Cozzoli Maria Maddalena Dinardo Roberta Caloiero Kejla Musaraj Adriano Fonzino Elena Conte Catherine Jagerschmidt Florence Namour Antonella Liantonio Annamaria De Luca Diana Conte Camerino Sabata Pierno 《PloS one》2015,10(6)
Muscle disuse produces severe atrophy and a slow-to-fast phenotype transition in the postural Soleus (Sol) muscle of rodents. Antioxidants, amino-acids and growth factors were ineffective to ameliorate muscle atrophy. Here we evaluate the effects of nandrolone (ND), an anabolic steroid, on mouse skeletal muscle atrophy induced by hindlimb unloading (HU). Mice were pre-treated for 2-weeks before HU and during the 2-weeks of HU. Muscle weight and total protein content were reduced in HU mice and a restoration of these parameters was found in ND-treated HU mice. The analysis of gene expression by real-time PCR demonstrates an increase of MuRF-1 during HU but minor involvement of other catabolic pathways. However, ND did not affect MuRF-1 expression. The evaluation of anabolic pathways showed no change in mTOR and eIF2-kinase mRNA expression, but the protein expression of the eukaryotic initiation factor eIF2 was reduced during HU and restored by ND. Moreover we found an involvement of regenerative pathways, since the increase of MyoD observed after HU suggests the promotion of myogenic stem cell differentiation in response to atrophy. At the same time, Notch-1 expression was down-regulated. Interestingly, the ND treatment prevented changes in MyoD and Notch-1 expression. On the contrary, there was no evidence for an effect of ND on the change of muscle phenotype induced by HU, since no effect of treatment was observed on the resting gCl, restCa and contractile properties in Sol muscle. Accordingly, PGC1α and myosin heavy chain expression, indexes of the phenotype transition, were not restored in ND-treated HU mice. We hypothesize that ND is unable to directly affect the phenotype transition when the specialized motor unit firing pattern of stimulation is lacking. Nevertheless, through stimulation of protein synthesis, ND preserves protein content and muscle weight, which may result advantageous to the affected skeletal muscle for functional recovery. 相似文献
172.
Erica Salvati Angela Rizzo Sara Iachettini Pasquale Zizza Chiara Cingolani Carmen D'Angelo Manuela Porru Chiara Mondello Aurora Aiello Antonella Farsetti Eric Gilson Carlo Leonetti Annamaria Biroccio 《Nucleic acids research》2015,43(3):1759-1769
Here, with the aim of obtaining insight into the intriguing selectivity of G-quadruplex (G4) ligands toward cancer compared to normal cells, a genetically controlled system of progressive transformation in human BJ fibroblasts was analyzed. Among the different comparative evaluations, we found a progressive increase of DNA damage response (DDR) markers throughout the genome from normal toward immortalized and transformed cells. More interestingly, sensitivity to G4 ligands strongly correlated with the presence of a basal level of DNA damage, including at the telomeres, where the chromosome ends were exposed to the DDR without concurrent induction of DNA repair activity, as revealed by the lack of 53BP1 recruitment and telomere aberrations. The link between telomere uncapping and the response to G4 stabilization was directly assessed by showing that a partial TRF2 depletion, causing a basal level of telomere localized DDR, rendered telomerized fibroblasts prone to G4-induced telomere damage and anti-proliferative defects. Taken together these data strongly indicate that the presence of a basal level of telomere-associated DDR is a determinant of susceptibility to G4 stabilization. 相似文献
173.
174.
Silvia?Rossi Caterina?Motta Valeria?Studer Giulia?Macchiarulo Elisabetta?Volpe Francesca?Barbieri Gabriella?Ruocco Fabio?Buttari Annamaria?Finardi Raffaele?Mancino Sagit?Weiss Luca?Battistini Gianvito?Martino Roberto?Furlan Jelena?Drulovic Diego?CentonzeEmail author 《Molecular neurodegeneration》2014,9(1):56
175.
Simone Cappello Giuseppe Mancini Alessandro Pistone Maurizio Azzaro Francesco Bottino Lucrezia Genovese Daniela Iannazzo Antonella Luciano Antonino Mamo Giovanni Neri Signorino Galvagno Santina Santisi Annamaria Visco Michail M. Yakimov 《Reviews in Environmental Science and Biotechnology》2014,13(4):369-375
Throughout the last century the increasing human activities in Antarctic region, particularly research expeditions, fishing, and tourism amplified the risk of oils spills at these high latitudes of the meridional hemisphere. A number of studies have been focused on chronic hydrocarbon contamination near Antarctic research stations revealing the presence and persistence of these human-derived contaminants. Marine ship-source oil spills in Antarctic region can have significant impacts on the marine environment. The key factors to effectively fight oil spills are a careful selection and proper use of the equipment and materials best suited to the critical local conditions. Despite the significant advances in the field of environmental recovery after an “oil spill” episode, research has recently shown that the usual techniques are often less effective than expected. This issue become much more relevant in the Antarctic case, not only for the incomparable environmental value of the Antarctic region but also for the extreme environmental conditions and the great distances from properly equipped centers, that make unfeasible sending naval vessels. Scope of the STRANgE Project is the preliminary design of a prototype floating platform, parachutable by plane, able to intervene as quickly as possible for the containment, removal and treatment/storage of the oil slick. New sorbent nanostructured materials and specialized Antarctic bacteria applications constitute the main innovations of this Project. 相似文献
176.
Annamaria Bevivino Patrizia Paganin Giovanni Bacci Alessandro Florio Maite Sampedro Pellicer Maria Cristiana Papaleo Alessio Mengoni Luigi Ledda Renato Fani Anna Benedetti Claudia Dalmastri 《PloS one》2014,9(8)
Land-use change is considered likely to be one of main drivers of biodiversity changes in grassland ecosystems. To gain insight into the impact of land use on the underlying soil bacterial communities, we aimed at determining the effects of agricultural management, along with seasonal variations, on soil bacterial community in a Mediterranean ecosystem where different land-use and plant cover types led to the creation of a soil and vegetation gradient. A set of soils subjected to different anthropogenic impact in a typical Mediterranean landscape, dominated by Quercus suber L., was examined in spring and autumn: a natural cork-oak forest, a pasture, a managed meadow, and two vineyards (ploughed and grass covered). Land uses affected the chemical and structural composition of the most stabilised fractions of soil organic matter and reduced soil C stocks and labile organic matter at both sampling season. A significant effect of land uses on bacterial community structure as well as an interaction effect between land uses and season was revealed by the EP index. Cluster analysis of culture-dependent DGGE patterns showed a different seasonal distribution of soil bacterial populations with subgroups associated to different land uses, in agreement with culture-independent T-RFLP results. Soils subjected to low human inputs (cork-oak forest and pasture) showed a more stable bacterial community than those with high human input (vineyards and managed meadow). Phylogenetic analysis revealed the predominance of Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes phyla with differences in class composition across the site, suggesting that the microbial composition changes in response to land uses. Taken altogether, our data suggest that soil bacterial communities were seasonally distinct and exhibited compositional shifts that tracked with changes in land use and soil management. These findings may contribute to future searches for bacterial bio-indicators of soil health and sustainable productivity. 相似文献
177.
Annamaria Sandomenico Valeria Severino Angela Chambery Annalia Focà Giuseppina Focà Claudio Farina Menotti Ruvo 《Molecular biotechnology》2013,54(3):983-995
Intravenous immunoglobulin are important bio-therapeutics used in the replacement therapy for primary and secondary immunodeficiencies, chronic inflammatory disorders and several autoimmune haematologic disorders. Currently, a number of immunoglobulin intravenous (IVIG) products have been approved by the Food and Drug Administration (FDA) and are available commercially. It is known that small differences in the manufacturing processes as well as in the formulations may affect their clinical efficacy and tolerability. Therefore, given the complexity of the multi-step process required for the isolation of IVIG from human plasma, it is necessary to ensure a rigorous quality control of final products. We show here that a set of different bioanalytical techniques can be conveniently used to comparatively characterize, at a quantitative and qualitative level, different lots of IVIG preparations and to unveil randomly occurring impurities which can also affect the overall product stability. We have used circular dichroism, surface plasmon resonance and two-dimensional electrophoresis (2DE), and have demonstrated that this combination of bioanalytical approaches is very useful to improve the quality control of antibodies and to monitor the reliability of the IVIG manufacturing process. 相似文献
178.
Marie Westwood Jean Bourbeau Paul W Jones Annamaria Cerulli Gorana Capkun-Niggli Gill Worthy 《Respiratory research》2011,12(1):40
Background
Interactions between spirometry and patient-reported outcomes in COPD are not well understood. This systematic review and study-level analysis investigated the relationship between changes in FEV1 and changes in health status with bronchodilator therapy.Methods
Six databases (to October 2009) were searched to identify studies with long-acting bronchodilator therapy reporting FEV1 and health status, dyspnoea or exacerbations. Mean and standard deviations of treatment effects were extracted for each arm of each study. Relationships between changes in trough FEV1 and outcomes were assessed using correlations and random-effects regression modelling. The primary outcome was St George''s Respiratory Questionnaire (SGRQ) total score.Results
Thirty-six studies (≥3 months) were included. Twenty-two studies (23,654 patients) with 49 treatment arms each contributing one data point provided SGRQ data. Change in trough FEV1 and change in SGRQ total score were negatively correlated (r = -0.46, p < 0.001); greater increases in FEV1 were associated with greater reductions (improvements) in SGRQ. The correlation strengthened with increasing study duration from 3 to 12 months. Regression modelling indicated that 100 mL increase in FEV1 (change at which patients are more likely to report improvement) was associated with a statistically significant reduction in SGRQ of 2.5 (95% CI 1.9, 3.1), while a clinically relevant SGRQ change (4.0) was associated with 160.6 (95% CI 129.0, 211.6) mL increase in FEV1. The association between change in FEV1 and other patient-reported outcomes was generally weak.Conclusions
Our analyses indicate, at a study level, that improvement in mean trough FEV1 is associated with proportional improvements in health status. 相似文献179.
Lucia Anna Muscarella Raffaela Barbano Vincenzo D'Angelo Massimiliano Copetti Michelina Coco Teresa Balsamo Annamaria la Torre Angelo Notarangelo Michele Troiano Salvatore Parisi Nadia Icolaro Domenico Catapano Vanna Maria Valori Fabio Pellegrini Giuseppe Merla Massimo Carella Vito Michele Fazio Paola Parrella 《Epigenetics》2011,6(3):317-325
180.
Microparticle powders for nasal delivery were formulated to contain the model drug, zolmitriptan, and varying proportions
of different polymers. The objective of the study was to investigate the effects of these formulative parameters on the surface
chemistry of the spray-dried microparticles and their potential for adhesion to the tested substrates, porcine mucin, and
nasal tissue. The polymers used were chitosans of varying ionization states and molecular weights and hydroxypropyl methyl
cellulose. The surface energies of the surfaces of the microparticles were determined using contact angle measurements and
the van Oss model. The theory of surface thermodynamics was applied to determine the theoretical potential for the different
materials to adhere to the substrates. It was found that the drug or polymers alone, as well as the various formulations,
were more likely to adhere to mucin than to nasal tissue. Further, there was a trend for higher molecular weight chitosans
to adhere better to the substrates than lower molecular weight chitosans. Similarly, adhesion was improved for formulations
with a higher content of polymers. These theoretical predictions may be compared with further experimental results and be
of use in making informed decisions on the choice of formulations for future expensive bio-studies. 相似文献