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81.
Serum From Advanced Heart Failure Patients Promotes Angiogenic Sprouting and Affects the Notch Pathway in Human Endothelial Cells 下载免费PDF全文
Micaela Pannella Cristiana Caliceti Francesca Fortini Giorgio Aquila Francesco Vieceli Dalla Sega Antonio Pannuti Cinzia Fortini Marco Bruno Morelli Alessandro Fucili Gloria Francolini Rebecca Voltan Paola Secchiero Giovanni Dinelli Emanuela Leoncini Manuela Ferracin Silvana Hrelia Lucio Miele Paola Rizzo 《Journal of cellular physiology》2016,231(12):2700-2710
82.
De Rosa MC Carelli Alinovi C Schininà ME Clementi ME Amato A Cappabianca MP Pezzotti M Giardina B 《Biochimica et biophysica acta》2007,1774(10):1299-1306
This study examines the functional and structural effects of amino acid substitution at alpha(1)beta(2) interface of Hb Santa Clara (beta 97His-->Asn). We have characterized the variation by a combination of electrospray ionisation mass spectrometry and DNA sequence analysis followed by oxygen-binding experiments. Functional studies outlined an increased oxygen affinity, reduced effect of organic phosphates and a reduced Bohr effect with respect to HbA. In view of the primary role of this interface in the cooperative quaternary transition from the T to R conformational state, a theoretical three-dimensional model of Hb Santa Clara was generated. Structural investigations suggest that replacement of Asn for His beta 97 results in a significant stabilization of the high affinity R-state of the haemoglobin molecule with respect to the low affinity T-state. The role of beta FG4 position has been further examined by computational models of known beta FG4 variants, namely Hb Malm? (beta 97His-->Gln), Hb Wood (beta 97His-->Leu), Hb Nagoya (beta 97His-->Pro) and Hb Moriguchi (beta 97His-->Tyr). These findings demonstrate that, among the various residues at the alpha(1)beta(2) (and alpha(2)beta(1)) intersubunit interface, His beta FG4 contributes significantly to the quaternary constraints that are responsible for the low oxygen affinity of human deoxyhaemoglobin. 相似文献
83.
Within the red blood cell the hemoglobin molecule is subjected to modulation mechanisms, namely homo- and heterotropic interactions, which optimize its functional behavior to the specific physiological requirements. At the cellular level, these modulation mechanisms are utilized to perform a number of other functions that are not minor with respect to the basic function of oxygen transport. Here we report some key examples concerning: (i) the interaction of hemoglobin with band 3 and its influence on glucose metabolism; (ii) the role of the ligand-linked quaternary transition of hemoglobin in the control of "NO bioactivity" and of gas diffusion; (iii) the interaction of plasma membrane with the various oxidative derivatives of the hemoglobin molecule. 相似文献
84.
Giovanni Caudullo Renzo De Battisti Cristiana Colpi Claudio Vazzola Flavio Da Ronch 《Journal for Nature Conservation》2003,10(4):233-241
The Cansiglio Forest, situated in the Veneto Prealps, is of particular naturalistic and landscape interest, going back to the times of the Most Serene Republic of Venice. Its long silvicultural tradition, which is now even more “near to nature”, remains unaltered. Over the last century there has been a considerable increase in the number of ungulates. This is partly due to prohibition of hunting since the beginning of the 20th century throughout the territory. It has therefore become necessary to survey forest regeneration, to ascertain whether deer pressure hampers silvicultural goals and also to investigate which factors are most involved. A review of management plans over the last 30 years identified areas in which regeneration is present, where transects were subsequently sampled. Inside every transect, all saplings (over 50 cm) were measured for diameter and height and monitored for degree and type of damage (browsing, debarking, fraying). Using the CART statistical method, the following key factors were singled out: species, proving that fir is the most frequently selected sapling; silvicultural system, clarifying that the regeneration of uneven-aged stands is more subject to damage; aspect, locating more damage in the southern and eastern areas, probably because they are more often frequented by deer. High densities of deer endanger fir survival, reduce biodiversity, and affect forest economy, limiting silvicultural choices, so that culling ungulate populations seems to be necessary. 相似文献
85.
86.
Joana Martins Martin L. Saker Cristiana Moreira Martin Welker Jutta Fastner Vitor M. Vasconcelos 《Applied microbiology and biotechnology》2009,82(5):951-961
Strains of the cyanobacterium Microcystis aeruginosa were isolated into pure culture from a variety of lakes, rivers, and reservoirs in Portugal. Samples were tested with matrix-assisted
laser desorption/ionization–time-of-flight mass spectrometry (MALDI-TOF MS) to investigate the presence of various peptide
groups including aeruginosins, microginins, anabaenopeptins, cyanopeptilins, microcystins, and microviridins and other peptide-like
compounds. Binary data, based on the presence and absence of different peptide groups, were analyzed by phylogenetic inference.
DNA was also extracted from the samples and tested using a range of primers. Those strains that gave positive results for
a Microcystis-specific primer pair were further analyzed for the presence of genes linked to the biosynthesis of microginin and microcystin.
The results showed that a wide range of microcystin forms were produced by the strains among which MC-LR, -FR, -RR, -WR, and
-YR were the most common. The peptide profiles obtained from the MALDI analysis were assessed using cluster analysis which
resulted in the formation of distinct groups or chemotypes. 相似文献
87.
Cristiana Pistol Tanase Simona Dima Mihaela Mihai Elena Raducan Mihnea Ioan Nicolescu Lucian Albulescu Bogdan Voiculescu Traian Dumitrascu Linda Maria Cruceru Mircea Leabu Irinel Popescu Mihail Eugen Hinescu 《Journal of molecular histology》2009,40(1):23-29
The assessment of caveolin-1 (Cav-1) as a marker of tumor aggressiveness in pancreatic ductal adenocarcinoma (PDAC). In this
study, we examined the expression of Cav-1 in 34 human PDAC tissue samples and the associated peritumoral tissues by immunohistochemistry
and western blot. Additionally, we correlated Cav-1 expression with other tissue (Ki-67, p53) and serum (CA 19-9) tumor markers.
In the tumor-derived tissue, both tumor cells and blood vessels expressed Cav-1. In contrast, in peritumoral tissue, Cav-1
expression was confined mainly to blood vessels and was only occasionally expressed in ductal or parenchymal cells. Western
blot analysis confirmed the overexpression of Cav-1 in pancreatic tumors compared with peritumoral tissue. Cav-1 expression
in tumor tissues was correlated with both the Ki-67 LI (r = 0.95, P < 0.0001) and p53 expression (χ2 = 9.91, P < 0.005). Overexpression of Cav-1 was associated with tumor size, grade and stage and Cav-1 expression in tumors was correlated
with an increased serum level of CA 19-9 (r = 0.795, P < 0.001). Based on the results of this study, the inclusion of Cav-1 in a putative panel of biomarkers predicting pancreatic
cancer aggressiveness is warranted. 相似文献
88.
Elena Perrin Marco Fondi Maria Cristiana Papaleo Isabel Maida Silvia Buroni Maria Rosalia Pasca Giovanna Riccardi Renato Fani 《BMC evolutionary biology》2010,10(1):164
Background
The genus Burkholderia includes a variety of species with opportunistic human pathogenic strains, whose increasing global resistance to antibiotics has become a public health problem. In this context a major role could be played by multidrug efflux pumps belonging to Resistance Nodulation Cell-Division (RND) family, which allow bacterial cells to extrude a wide range of different substrates, including antibiotics. This study aims to i) identify rnd genes in the 21 available completely sequenced Burkholderia genomes, ii) analyze their phylogenetic distribution, iii) define the putative function(s) that RND proteins perform within the Burkholderia genus and iv) try tracing the evolutionary history of some of these genes in Burkholderia. 相似文献89.
90.
ASPM and CITK regulate spindle orientation by affecting the dynamics of astral microtubules 下载免费PDF全文