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排序方式: 共有255条查询结果,搜索用时 31 毫秒
111.
Erinna F. Lee Matthew A. Perugini Anne Pettikiriarachchi Marco Evangelista David W. Keizer 《Autophagy》2016,12(3):460-471
BECN1/Beclin 1 has a critical role in the early stages of autophagosome formation. Recently, structures of its central and C-terminal domains were reported, however, little structural information is available on the N-terminal domain, comprising a third of the protein. This lack of structural information largely stems from the inability to produce this region in a purified form. Here, we describe the expression and purification of the N-terminal domain of BECN1 (residues 1 to 150) and detailed biophysical characterization, including NMR spectroscopy. Combined, our studies demonstrated at the atomic level that the BECN1 N-terminal domain is intrinsically disordered, and apart from the BH3 subdomain, remains disordered following interaction with a binding partner, BCL2L1/BCL-XL. In addition, the BH3 domain α-helix induced upon interaction with BCL2L1 reverts to a disordered state when the complex is dissociated by exposure to a competitive inhibitor. No significant interactions between N- and C-terminal domains were detected. 相似文献
112.
Gabriele Finco Emanuela Locci Paolo Mura Roberta Massa Antonio Noto Mario Musu Giovanni Landoni Ernesto d’Aloja Fabio De-Giorgio Paola Scano Maurizio Evangelista 《PloS one》2016,11(3)
The diagnosis of pain nature is a troublesome task and a wrong attribution often leads to an increase of costs and to avoidable pharmaceutical adverse reactions. An objective and specific approach to achieve this diagnosis is highly desirable. The aim of this work was to investigate urine samples collected from patients suffering from pain of different nature by a metabolomics approach based on 1H NMR spectroscopy and multivariate statistical analysis. We performed a prospective study on 74 subjects: 37 suffering from pain (12 with nociceptive and 25 with neuropathic pain), and 37 controls not suffering from any kind of chronic pain. The application of discriminant analysis on the urine spectral profiles allowed us to classify these two types of pain with high sensibility and specificity. Although the classification relies on the global urine metabolic profile, the individual contribution in discriminating neuropathic pain patients of metabolites such as choline and phosphocholine, taurine and alanine, suggests potential lesions to the nervous system. To the best of our knowledge, this is the first time that a urine metabolomics profile is used to classify these two kinds of pain. This methodology, although based on a limited sample, may constitute the basis for a new helpful tool in the clinical diagnosis. 相似文献
113.
Alexei Santiani Shirley Evangelista Néstor Sepúlveda Jennie Risopatrón Juana Villegas Raúl Sánchez 《Theriogenology》2014
High levels of reactive oxygen species (ROS), which may be related to reduced semen quality, are detected during semen cryopreservation in some species. The objectives of this study were to measure the oxidative stress during ram semen cryopreservation and to evaluate the effect of adding 2 antioxidant mimics of superoxide dismutase (Tempo and Tempol) during the cooling process on sperm motility, viability, acrosomal integrity, capacitation status, ROS levels, and lipid peroxidation in frozen and/or thawed ram spermatozoa. Measuring of ROS levels during the cooling process at 35, 25, 15, and 5 °C and after freezing and/or thawing showed a directly proportional increase (P < 0.05) when temperatures were lowering. Adding antioxidants at 10 °C confered a higher motility and sperm viability after cryopreservation in comparison with adding at 35 °C or at 35 °C/5 °C. After freezing and/or thawing, sperm motility was significantly higher (P < 0.05) in Tempo and Tempol 1 mM than that in control group. Percentage of capacitated spermatozoa was lower (P < 0.05) in Tempo and Tempol 1 mM in comparison with that in control group. In addition, ROS levels and lipid peroxidation in group Tempo 1 mM were lower (P < 0.05) than those in control group. These results demonstrate that ram spermatozoa are exposed to oxidative stress during the cooling process, specifically when maintained at 5 °C and that lipid peroxidation induced by high levels of ROS decreases sperm motility and induces premature sperm capacitation. In contrast, the addition of Tempo or Tempol at 0.5 to 1 mM during the cooling process (10 °C) protects ram spermatozoa from oxidative stress. 相似文献
114.
115.
Barba M Cavalleri A Schünemann HJ Krogh V Evangelista A Secreto G Micheli A Zhou Q Fuhrman B Teter B Berrino F Muti P 《The International journal of biological markers》2006,21(4):242-245
The objective of this study is to evaluate the effect of cryopreservation at different storage temperatures on urinary 6-sulfatoxymelatonin (aMT6s) concentration. Overnight urine from 28 postmenopausal women participating in the ORDET cohort study was filtered and separated into 6 mL aliquots. Urine samples were stored at -80 degrees C and at -30 degrees C for an average of 14 years. Urinary aMT6s concentration was assessed using a competitive immunoassay. Mean aMT6s values of samples stored at -30 degrees C were systematically lower than those of samples stored at -80 degrees C (10.7 ng/mL versus 15.8 ng/mL, p<0.001). Bland Altman plots showed disagreement between determinations at different storage temperatures at the highest levels of the metabolite concentration. The degree of agreement evaluated in terms of intraclass correlation coefficient was 0.68 (95% CI 0.41-0.84, p<0.0001). Pearson's correlation coefficient between aMT6s values of the two differently stored samples was 0.93 (p<0.001), while the Kendal tau coefficient for rank distribution was 0.73 (p<0.001). Our data suggest that storage temperatures might affect degradation of aMT6s during storage. However, individual characterization by melatonin levels does not seem to be affected by cryopreservation conditions. 相似文献
116.
Poliseno L Cecchettini A Mariani L Evangelista M Ricci F Giorgi F Citti L Rainaldi G 《Tissue & cell》2006,38(2):111-120
Vascular smooth muscle (VSM) cells constitute the main structural components of tunica media. Under physiological conditions, these cells display a contractile phenotype and a low proliferative activity. However, they may also acquire a synthetic phenotype and become predominantly proliferative if stimulated under certain stress conditions. This capacity plays a major role in the inception and progression of such cardiovascular diseases as atherosclerosis, hypertension and restenosis. Porcine coronary smooth muscle (PCSM) cells exhibit a synthetic phenotype (ON cells) under standard culturing conditions, but they can be reverted to a contractile phenotype (OFF cells) in a serum-free medium. However, OFF cells can also re-acquire a synthetic phenotype (OFF/ON cells) upon serum administration. In the present study, proliferative and contractile behaviors were characterized by expression of specific differentiation markers. Taken together, these results demonstrate that porcine vascular smooth muscle cells can retain their phenotypic plasticity in culture, and thus mimic in vitro their in vivo differentiation states. OFF cells may thus provide a suitable model system in studying the mechanism(s) by which either known or unknown serum factors may trigger vascular smooth muscle activation. In the present study, this possibility was actually tested by exposing OFF cells to fetal bovine serum (FBS), PDGF-BB and IGF-I. Data show that only FBS could induce a synthetic phenotype in OFF cells, while both PDGF-BB and IGF-I failed to induce any VSM activation. 相似文献
117.
Katarzyna Prymula Monika Piwowar Marek Kochanczyk Lukasz Flis Maciej Malawski Tomasz Szepieniec Giovanni Evangelista Giuseppe Minervini Fabio Polticelli Zdzisław Wiśniowski Kinga Sałapa Ewa Matczyńska Irena Roterman 《化学与生物多样性》2009,6(12):2311-2336
The three‐dimensional structures of a set of ‘never born proteins’ (NBP, random amino acid sequence proteins with no significant homology with known proteins) were predicted using two methods: Rosetta and the one based on the ‘fuzzy‐oil‐drop’ (FOD) model. More than 3000 different random amino acid sequences have been generated, filtered against the non redundant protein sequence data base, to remove sequences with significant homology with known proteins, and subjected to three‐dimensional structure prediction. Comparison between Rosetta and FOD predictions allowed to select the ten top (highest structural similarity) and the ten bottom (the lowest structural similarity) structures from the ranking list organized according to the RMS‐D value. The selected structures were taken for detailed analysis to define the scale of structural accordance and discrepancy between the two methods. The structural similarity measurements revealed discrepancies between structures generated on the basis of the two methods. Their potential biological function appeared to be quite different as well. The ten bottom structures appeared to be ‘unfoldable’ for the FOD model. Some aspects of the general characteristics of the NBPs are also discussed. The calculations were performed on the EUChinaGRID grid platform to test the performance of this infrastructure for massive protein structure predictions. 相似文献
118.
Verduci L Simili M Rizzo M Mercatanti A Evangelista M Mariani L Rainaldi G Pitto L 《The Journal of biological chemistry》2010,285(50):39551-39563
119.
Manoel Marques Evangelista de Oliveira Rodrigo de Almeida-Paes Mauro de Medeiros Muniz Monica Bastos de Lima Barros Maria Clara Gutierrez Galhardo Rosely Maria Zancope-Oliveira 《Mycopathologia》2010,169(5):359-363
This report describes the first isolation of Sporothrix globosa from a Brazilian patient. A 77-year-old woman was examined for sporotrichosis infection. Histopathological examination of
skin biopsy revealed chronic granulomatous infiltrate with microabcess. Furthermore, S. schenckii-like yeasts were evident as demonstrated by PAS and Grocott stains. The fungus was identified based on colony morphology
on Sabouraud Dextrose Agar slants, Potato Dextrose Agar, and Corn Meal Agar, microscopic morphology on slides cultures, and
assimilation of different carbon sources. The species confirmation was made by molecular methodology. 相似文献
120.
Laura Barsanti Anna Maria Frassanito Vincenzo Passarelli Valtere Evangelista Maryam Etebari Eugenio Paccagnini Pietro Lupetti Paola Lenzi Franco Verni Paolo Gualtieri 《Journal of phycology》2013,49(1):178-193
Morphological, ultrastructural, and molecular‐sequence data were used to assess the phylogenetic position of a tetraflagellate green alga isolated from soil samples of a saline dry basin near F'derick, Mauritania. This alga can grow as individual cells or form non‐coenobial colonies of up to 12 individuals. It has a parietal chloroplast with an embedded pyrenoid covered by a starch sheath and traversed by single parallel thylakoids, and an eyespot located in a parietal position opposite to the flagellar insertion. Lipid vacuoles are present in the cytoplasm. Microspectroscopy indicated the presence of chlorophylls a and b, with lutein as the major carotenoid in the chloroplast, while the eyespot spectrum has a shape typical of green‐algal eyespots. The cell has four flagella, two of them long and two considerably shorter. Sequence data from the 18S rRNA gene and ITS2 were obtained and compared with published sequences for green algae. Results from morphological and ultrastructural examinations and sequence analysis support the placement of this alga in the Chlorophyceae, as Tetraflagellochloris mauritanica L. Barsanti et A. Barsanti, gen. et sp. nov. 相似文献