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排序方式: 共有460条查询结果,搜索用时 15 毫秒
91.
Marcello Maggio Gian Paolo Ceda Andrea Ticinesi Francesca De Vita Giovanni Gelmini Cosimo Costantino Tiziana Meschi Reto W. Kressig Matteo Cesari Massimo Fabi Fulvio Lauretani 《PloS one》2016,11(4)
BackgroundManual measurement of 4-meter gait speed by a stopwatch is the gold standard test for functional assessment in older adults. However, the accuracy of this technique may be biased by several factors, including intra- and inter-operator variability. Instrumental techniques of measurement using accelerometers may have a higher accuracy. Studies addressing the concordance between these two techniques are missing. The aim of the present community-based observational study was to compare manual and instrumental measurements of 4-meter gait speed in older individuals and to assess their relationship with other indicators of physical performance.MethodsOne-hundred seventy-two (69 men, 103 women) non-disabled community-dwellers aged ≥65 years were enrolled. They underwent a comprehensive geriatric assessment including physical function by Short Physical Performance Battery (SPPB), hand grip strength, and 6-minute walking test (6MWT). Timed usual walking speed on a 4-meter course was assessed by using both a stopwatch (4-meter manual measurement, 4-MM) and a tri-axial accelerometer (4-meter automatic measurement, 4-MA). Correlations between these performance measures were evaluated separately in men and women by partial correlation coefficients.ResultsIn both genders, 4-MA was associated with 4-MM (men r = 0.62, p<0.001; women r = 0.73, p<0.001), handgrip strength (men r = 0.40, p = 0.005; women r = 0.29, p = 0.001) and 6MWT (men r = 0.50, p = 0.0004; women r = 0.22, p = 0.048). 4-MM was associated with handgrip strength and 6MWT in both men and women. Considering gait speed <0.6 m/s as diagnostic of dismobility syndrome, the two methods of assessment disagreed, with a different categorization of subjects, in 19% of men and 23% of women. The use of accelerometer resulted in 29 (13 M, 16 F) additional diagnoses of dismobility, compared with the 4-MM.ConclusionsIn an older population, the concordance of gait speeds manually or instrumentally assessed is not optimal. The results suggest that manual measures might lead to misclassification of a substantial number of subjects. However, longitudinal studies using standardized and validated procedures aimed at the comparison of different techniques are needed before recommending the use of accelerometers in comprehensive geriatric assessment. 相似文献
92.
Renata Barsacchi Paolo Camici Ubaldo Bottigli Piero A. Salvadori Gualtiero Pelosi Matilde Maiorino Fulvio Ursini 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》1983,762(2):241-247
The isolated perfused rat heart emits a spontaneous ultraweak chemiluminescence. When the perfusion is stopped, light emission decreases, indicating the dependency of this phenomenon on aerobic metabolism. Emitted chemiluminescence was markedly enhanced following perfusion with 0.05 mM H2O2 or cumene hydroperoxide or tert-butyl hydroperoxide; substitution of O2 for N2 in the gassing mixture of the perfusion media significantly lowered photon emission. Lipid peroxidation, which is known to be associated with chemiluminescence, was evaluated by HPLC analysis of peroxidized and unperoxidized heart phosphatidylcholines. During hydroperoxide perfusion, coronary flow and heart rate progressively decreased, while lactic dehydrogenase was released after complete cardiac arrest. The resultant morphology of this damage corresponds to the so-called ‘stone heart’, a pattern already described in both human and experimental pathology. 相似文献
93.
Krasnowska EK Pittaluga E Brunati AM Brunelli R Costa G De Spirito M Serafino A Ursini F Parasassi T 《Free radical biology & medicine》2008,45(11):1566-1572
The non-receptor-protein tyrosine kinase c-Src is overexpressed and activated in a large number of human cancers, in which it is associated with tumor development and progression. Canonical regulation takes place by means of an alternative phosphorylation of tyrosine residues -- Tyr419 for activation and Tyr530 for inactivation. An independent redox regulation mechanism, involving cysteine residues, has also been proposed, in which oxidation activates the enzyme. Here we present a kinetic analysis of the effect of N-acetyl-l-cysteine (NAC) on c-Src, demonstrating that reduction reverts the oxidation-driven activation. In cancer cells, we show that NAC treatment produces an increase in specifically labeled reduced thiols of c-Src cysteines, thus confirming a redox transition. In addition to a decrease in Tyr419 phosphorylation, this leads to a massive shift of c-Src from plasma membranes -- where its active form is located -- to endolysosomal compartments. With the objective of deciphering the complex issue of c-Src regulation and of devising new strategies to revert its activation in cancers, redox regulation thus emerges as a promising area for study. 相似文献
94.
Reactivity of Phospholipid Hydroperoxide Glutathione Peroxidase with Membrane and Lipoprotein Lipid Hydroperoxides 总被引:5,自引:0,他引:5
Matilde Maiorino James P. Thomas Albert W. Girotti Fulvio Ursini 《Free radical research》1991,12(1):131-135
A comparative study has been carried out on the general reactivity of lipid hydroperoxides in liposornes, biological membranes and lipoproteins with two Se-dependent peroxidases: Glutathione Peroxidase (GPX) and Phospholipid Hydroperoxide Glutathione Peroxidase (PHGPX). While PHGPX reduces all hydroperoxides derived from phospholipids, cholesterol and cholesterol esters, GPX reduces only fatty acid hydroperoxides released after treatment of phospholipid hydroperoxides with phospholipase A,. These findings highlight the role of PHGPX in protecting biomembranes from peroxidative damage and add new insight into how cholesterol hydroperoxides are detossified in cells. 相似文献
95.
Nicola Scichilone Maria T Ventura Matteo Bonini Fulvio Braido Caterina Bucca Marco Caminati Stefano Del Giacco Enrico Heffler Carlo Lombardi Andrea Matucci Manlio Milanese Roberto Paganelli Giovanni Passalacqua Vincenzo Patella Erminia Ridolo Giovanni Rolla Oliviero Rossi Domenico Schiavino Gianenrico Senna Gundi Steinhilber Alessandra Vultaggio Giorgio Canonica 《Clinical and molecular allergy : CMA》2015,13(1)
The prevalence of asthma in the most advanced ages is similar to that of younger ages. However, the concept that older individuals may suffer from allergic asthma has been largely denied in the past, and a common belief attributes to asthma the definition of “rare” disease. Indeed, asthma in the elderly is often underdiagnosed or diagnosed as COPD, thus leading to undertreatment of improper treatment. This is also due to the heterogeneity of clinical and functional presentations of geriatric asthma, including the partial loss of reversibility and the lower occurrence of the allergic component in this age range. The older asthmatic patients are also characterized the coexistence of comorbid conditions that, in conjunction with age-associated structural and functional changes of the lung, may contribute to complicate the management of asthma. The current review addresses the main issues related to the management of allergic asthma in the geriatric age. In particular, the paper aims at revising current pharmacological and non pharmacological treatments for allergic asthmatics of advanced ages, primarily focusing on their safety and efficacy, although most behaviors are an arbitrary extrapolation of what has been tested in young ages. In fact, age has always represented an exclusion criterion for eligibility to clinical trials. Experimental studies and real life observations specifically testing the efficacy and safety of therapeutic approaches in allergic asthma in the elderly are urgently needed. 相似文献
96.
Alessandra di Penta Valentina Mercaldo Fulvio Florenzano Sebastian Munck M. Teresa Ciotti Francesca Zalfa Delio Mercanti Marco Molinari Claudia Bagni Tilmann Achsel 《The Journal of cell biology》2009,184(3):423-435
Messenger RNA (mRNA) transport to neuronal dendrites is crucial for synaptic plasticity, but little is known of assembly or translational regulation of dendritic messenger ribonucleoproteins (mRNPs). Here we characterize a novel mRNP complex that is found in neuronal dendrites throughout the central nervous system and in some axonal processes of the spinal cord. The complex is characterized by the LSm1 protein, which so far has been implicated in mRNA degradation in nonneuronal cells. In brain, it associates with intact mRNAs. Interestingly, the LSm1-mRNPs contain the cap-binding protein CBP80 that associates with (pre)mRNAs in the nucleus, suggesting that the dendritic LSm1 complex has been assembled in the nucleus. In support of this notion, neuronal LSm1 is partially nuclear and inhibition of mRNA synthesis increases its nuclear localization. Importantly, CBP80 is also present in the dendrites and both LSm1 and CBP80 shift significantly into the spines upon stimulation of glutamergic receptors, suggesting that these mRNPs are translationally activated and contribute to the regulated local protein synthesis. 相似文献
98.
Cheong H Yorimitsu T Reggiori F Legakis JE Wang CW Klionsky DJ 《Molecular biology of the cell》2005,16(7):3438-3453
Autophagy is a catabolic process used by eukaryotic cells for the degradation and recycling of cytosolic proteins and excess or defective organelles. In yeast, autophagy is primarily a response to nutrient limitation, whereas in higher eukaryotes it also plays a role in developmental processes. Due to its essentially unlimited degradative capacity, it is critical that regulatory mechanisms are in place to modulate the timing and magnitude of the autophagic response. One set of proteins that seems to function in this regard includes a complex that contains the Atg1 kinase. Aside from Atg1, the proteins in this complex participate primarily in either nonspecific autophagy or specific types of autophagy, including the cytoplasm to vacuole targeting pathway, which operates under vegetative growth conditions, and peroxisome degradation. Accordingly, these proteins are prime candidates for factors that regulate the conversion between these pathways, including the change in size of the sequestering vesicle, the most obvious morphological difference. The atg17delta mutant forms a reduced number of small autophagosomes. As a result, it is defective in peroxisome degradation and is partially defective for autophagy. Atg17 interacts with both Atg1 and Atg13, via two coiled-coil domains, and these interactions facilitate its inclusion in the Atg1 complex. 相似文献
99.
Muriel Mari Janice Griffith Ester Rieter Lakshmi Krishnappa Daniel J. Klionsky Fulvio Reggiori 《The Journal of cell biology》2010,190(6):1005-1022
Eukaryotes use the process of autophagy, in which structures targeted for lysosomal/vacuolar degradation are sequestered into double-membrane autophagosomes, in numerous physiological and pathological situations. The key questions in the field relate to the origin of the membranes as well as the precise nature of the rearrangements that lead to the formation of autophagosomes. We found that yeast Atg9 concentrates in a novel compartment comprising clusters of vesicles and tubules, which are derived from the secretory pathway and are often adjacent to mitochondria. We show that these clusters translocate en bloc next to the vacuole to form the phagophore assembly site (PAS), where they become the autophagosome precursor, the phagophore. In addition, genetic analyses indicate that Atg1, Atg13, and phosphatidylinositol-3-phosphate are involved in the further rearrangement of these initial membranes. Thus, our data reveal that the Atg9-positive compartments are important for the de novo formation of the PAS and the sequestering vesicle that are the hallmarks of autophagy. 相似文献
100.
Sarto C Valsecchi C Magni F Tremolada L Arizzi C Cordani N Casellato S Doro G Favini P Perego RA Raimondo F Ferrero S Mocarelli P Galli-Kienle M 《Proteomics》2004,4(8):2252-2260
Heat shock protein 27 (HSP27, Swiss-Prot accession number P04792) is a component of the large and heterogeneous group of chaperone proteins, and its main functions are inhibition of apoptosis and prevention of aggregation of actin intermediate filament. Modified expression of HSP27 has been described in several cancers including testis, breast, and ovaric cancer. In the present work, 18 renal cell carcinoma (RCC) tissues and homologous normal kidney tissues have been investigated for HSP27 expression by combination of two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) separation and Western blotting immunodetection. The results showed significant differences either in expression and in HSP27 isoform numbers in RCC compared to normal kidney. The average number of isoforms was 21 in RCC and 15 in normal tissues with 4.5-5.9 pI range and 18-29 kDa M(r) range. The overexpression was also observed by immunohistochemistry on tissue sections. Only two of RCC samples showed less isoforms than homologous normal samples. Two isoforms were not detected using anti-Ser82 phosphorylated HSP27 antibody, neither in normal nor in RCC samples. Five of all the immunodetected isoforms were confirmed by mass spectrometry as HSP27, but no evidence of post-translational modifications was pointed out. The numerous isoforms observed in RCC are not consistent with data reported in the literature so far, and they might be due to different post-translational modifications such as phosphorylation and S-thiolation. Since activation of HSP27 seems to be involved in tumor proliferation and drug resistance, it would be crucial to correlate the severity of disease with the different isoforms from RCC samples to generate diagnostic and prognostic markers. 相似文献