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71.
Cluster Computing - Cloud platforms usually offer several types of Virtual Machines (VMs) with different guarantees in terms of availability and volatility, provisioning the same resource through... 相似文献
72.
Donato Chiatante Gabriella S. Scippa Lucia Maiuro Elisabetta Onelli Giuseppe Patrignani 《Plant biosystems》2013,147(1):35-47
ABSTRACT To understand the mechanisms which enable the nucleus to function under low water potential, the morphology and biochemistry of potato cell nuclei were studied. Conformational modifications were observed in the chromatin of nuclei of cells growing under low water potential. These modifications include a higher number of heterochromatic centres, enlargement of the nuclear diameter, and a different accessibility of DNA to the action of restriction enzymes. Biochemical analyses showed that these chromatin modifications may coincide with quantitative and qualitative variations of several nuclear proteins, some of which may belong to the dehydrin family. We especially focussed our attention on a 45-kDa protein that is heat-stable and is recognised by an antibody raised against the conserved domain of dehydrins. The survival of potato cells in an environment where water availability is low may depend on several simultaneous events regarding the nucleus. The accumulation in the nucleus of specific proteins such as dehydrins could be required to stabilise the chromatin by means of their molecule-salvation action. Further studies are in progress to check whether or not variations in chromatin organisation may be one of the numerous traits that a cell must acquire to become water-stress resistant. 相似文献
73.
Lucia Ciccoli Viviana Rossi Silvia Leoncini Cinzia Signorini Patrizia Paffetti Rodolfo Bracci 《Free radical research》2013,47(1):51-58
Iron is released in a desferrioxamine (DFO)-chelatable form (DCI) when erythrocytes are challenged by an oxidative stress. In g -thalassemic erythrocytes, both DCI content and release (after aerobic incubation for 24 h) are increased and correlated with the fetal hemoglobin (HbF) levels. Since erythrocytes from newborns have an extremely high content of HbF and are exposed to conditions of oxidative stress, the release of iron in these erythrocytes was investigated. The erythrocyte DCI content was increased in preterm but not in term newborns as compared to adults, while the release was increased in both preterm and term erythrocytes. The level of plasma non protein-bound iron (NPBI), which was not detectable in adults, was much higher in preterm than in term newborns. When term plus preterm newborns were divided in two groups, normoxic and hypoxic, according to cord blood pH, it was found that both iron release and NBPI were markedly higher in the hypoxic newborns compared to normoxic ones. Similar results were also obtained when the preterm and term infants were considered separately on the basis of cord blood pH. Therefore, iron release and NPBI are higher when conditions of hypoxia occur. In fact, when the values for iron release and NPBI were separately plotted against cord blood pH values, significant negative correlations were seen in both cases. NPBI was correlated with iron release seen in all the newborns and a significant part of the released iron could be recovered into the incubation medium at the end of the incubation. 相似文献
74.
Carlo Dani Lucia Giannini Giovanna Bertini Simone Pratesi Iuri Corsini Mariangela Longini 《Free radical research》2013,47(12):1358-1363
The higher risk of respiratory problem in infants delivered by elective caesarean section in comparison with vaginally born infants may be favoured by lower level of nitric oxide (NO) and carbon monoxide (CO) and higher oxidative stress in infants born by caesarean section. We studied healthy term infants born by vaginal delivery or by elective caesarean section. Nitric oxide, CO, guanosine 3–5 cyclic monophosphate, total hydroperoxide and advanced oxidation protein products (AOPP) were measured at birth and 48–72 h of life. Nitric oxide, CO and cGMP were lower at birth and at 48–72 h of life in infants born by elective caesarean delivery. Total hydroperoxide and AOPP levels were similar in the two groups and increased from birth to 48–72 h of life. In conclusion, nitric oxide and CO concentrations were higher in term infants vaginally born than in infants born by elective caesarean section and decreased from birth to 48–72 h of life. The mode of delivery did not affect the oxidative stress which increases from birth to 48–72 h of life. 相似文献
75.
This paper studied the effect on UV-B ocular damage of 10µm hydrocaffeic acid (HCAF) alone and as a mixture (MIX) (5µm HCAF+5µm p-coumaric acid). Since ocular UV-B damage is mediated by reactive oxygen species, the aim was to test if HCAF and MIX could reduce oxidation damage in human conjunctival cells (WKD) in vitro and in cornea and sclera of rabbits in vivo. After UVB irradiation (44 J/m2) of WKD cells, 8-oxodG levels in DNA were markedly increased and this effect was attenuated by HCAF and MIX. Rabbit eyes were treated by application of HCAF and MIX drops before UV-B exposure (79 J/m2). Corneal and scleral DNA oxidation damage, xanthine-oxidase (XO) activity and malondialdehyde levels (MDA) in corneal tissue and prostaglandin E2 (PGE2) in the aqueous humour were reduced by HCAF alone and in combination with p-coumaric acid, showing their potential as a topical treatment against UV-B damage. 相似文献
76.
Angela Oppelt Viola H Lobert Kaisa Haglund Ashley M Mackey Lucia E Rameh Knut Liestøl Kay Oliver Schink Nina Marie Pedersen Eva M Wenzel Ellen M Haugsten Andreas Brech Tor Erik Rusten Harald Stenmark Jørgen Wesche 《EMBO reports》2013,14(1):57-64
Although phosphatidylinositol 5‐phosphate (PtdIns5P) is present in many cell types and its biogenesis is increased by diverse stimuli, its precise cellular function remains elusive. Here we show that PtdIns5P levels increase when cells are stimulated to move and we find PtdIns5P to promote cell migration in tissue culture and in a Drosophila in vivo model. First, class III phosphatidylinositol 3‐kinase, which produces PtdIns3P, was shown to be involved in migration of fibroblasts. In a cell migration screen for proteins containing PtdIns3P‐binding motifs, we identified the phosphoinositide 5‐kinase PIKfyve and the phosphoinositide 3‐phosphatase MTMR3, which together constitute a phosphoinositide loop that produces PtdIns5P via PtdIns(3,5)P2. The ability of PtdIns5P to stimulate cell migration was demonstrated directly with exogenous PtdIns5P and a PtdIns5P‐producing bacterial enzyme. Thus, the identified phosphoinositide loop defines a new role for PtdIns5P in cell migration. 相似文献
77.
Alessandra Vacca Roberta Montisci Pietro Garau Paolo Siotto Matteo Piga Alberto Cauli Massimo Ruscazio Luigi Meloni Sabino Iliceto Alessandro Mathieu 《Arthritis research & therapy》2013,15(1):R8
Introduction
Microcirculation dysfunction is a typical feature of systemic sclerosis (SSc) and represents the earliest abnormality of primary myocardial involvement. We assessed coronary microcirculation status by combining two functional tests in SSc patients and estimating its impact on disease outcome.Methods
Forty-one SSc patients, asymptomatic for coronary artery disease, were tested for coronary flow velocity reserve (CFR) by transthoracic-echo-Doppler with adenosine infusion (A-TTE) and for left ventricular wall motion abnormalities (WMA) by dobutamine stress echocardiography (DSE). Myocardial multi-detector computed tomography (MDCT) enabled the presence of epicardial stenosis, which could interfere with the accuracy of the tests, to be excluded. Patient survival rate was assessed over a 6.7- ± 3.5-year follow-up.Results
Nineteen out of 41 (46%) SSc patients had a reduced CFR (≤2.5) and in 16/41 (39%) a WMA was observed during DSE. Furthermore, 13/41 (32%) patients showed pathological CFR and WMA. An inverse correlation between wall motion score index (WMSI) during DSE and CFR value (r = -0.57, P <0.0001) was observed; in addition, CFR was significantly reduced (2.21 ± 0.38) in patients with WMA as compared to those without (2.94 ± 0.60) (P <0.0001). In 12 patients with abnormal DSE, MDCT was used to exclude macrovasculopathy. During a 6.7- ± 3.5-year follow-up seven patients with abnormal coronary functional tests died of disease-related causes, compared to only one patient with normal tests.Conclusions
A-TTE and DSE tests are useful tools to detect non-invasively pre-clinical microcirculation abnormalities in SSc patients; moreover, abnormal CFR and WMA might be related to a worse disease outcome suggesting a prognostic value of these tests, similar to other myocardial diseases. 相似文献78.
Leandro Freire dos Santos Ana Lucia Zanatta Vanete Thomaz Soccol Maria Fernanda Torres Sandro José Ribeiro Bonatto Rosália Rubel Carlos Ricardo Soccol 《Biotechnology and Bioprocess Engineering》2013,18(1):201-208
The ability of Pleurotus ostreatus biomass, cultived by submerged fermentation, to produce beneficial effect on lipid profile and macrophages activity during a high-fat diet (HFD) for a long-term intake was investigated. Blood samples were collected through cardiac puncture to measure the plasma cholesterol, triglycerides, low-density protein (LDL), high-density protein (HDL), aspartate aminotransferase (AST) activity, urea-blood urea nitrogen (BUN)/creatinine ratio of rats fed on an HFD for 4 months. Dosage of lipid hydroperoxides was carried out on methanolic extract of liver tissue. Peritoneal macrophages activity was evaluated in relation to the superoxide anion, hydrogen peroxide and nitric oxide production, phagocytosis and lysosomal volume. The administration of P. ostreatus significantly altered the lipid profile and oxidative stress as related to the LDL and triglycerides decrease and inhibitory effects on superoxide anion and hydrogen peroxide production. All findings of this study lead us to suggest that the P. ostreatus maybe a beneficial agent in the hyperlipidemia and atherosclerosis treatments. 相似文献
79.
Alessandro Cannavo Giuseppe Rengo Daniela Liccardo Gianluigi Pironti Maria Cecilia Scimia Laura Scudiero Claudio De Lucia Marco Ferrone Dario Leosco Nicola Zambrano Walter J. Koch Bruno Trimarco Giovanni Esposito 《Apoptosis : an international journal on programmed cell death》2013,18(10):1252-1261
The human prothymosin alpha (PTα) gene encodes a 12.5 kDa highly acidic nuclear protein that is widely expressed in mammalian tissues including the heart and importantly, is detectable also in blood serum. During apoptosis or necrosis, PTα changes its nuclear localization and is able to exert an important cytoprotective effect. Since the role of PTα in the heart has never been evaluated, the aim of the present study was to investigate the effects of PTα on cardiomyocytes during ischemic injury. Our data show that seven after myocardial infarction (MI), PTα expression levels are significantly increased both in blood serum and in cardiac tissue, and notably we observe that PTα translocates from the nuclei to cytoplasm and plasma membrane of cardiomyocytes following MI. Furthermore, in vitro experiments in cardiomyocytes, confirm that after 6 h of simulated ischemia (SI), PTα protein levels are upregulated compared to normoxic cells. Importantly, treatment of cardiomyocytes with a recombinant PTα (rPTα), during SI results in a significant decrease in the apoptotic response and in a robust increase in cell survival. Moreover, these effects are accompanied to a significant preservation of the activated levels of the anti-apoptotic serine-threonine kinase Akt. Consistent with our in vitro observation, rPTα-treated MI mice exhibit a strong reduction in infarct size at 24 h, compared to the MI control group and at the molecular level, PTα treatment induces activation of Akt. The present study provides for the first time the demonstration that PTα offers cardioprotection against ischemic injury by an Akt-dependent mechanism. 相似文献
80.
Lucia Fernandez-Arrojo Barbara Rodriguez-Colinas Patricia Gutierrez-Alonso Maria Fernandez-Lobato Miguel Alcalde Antonio O. Ballesteros Francisco J. Plou 《Process Biochemistry》2013,48(4):677-682
A modification of the classical calcium alginate enzyme entrapment technique is described aiming to overcome some of the limitations of the former gel-based biocatalysts. Dried alginate entrapped enzymes (DALGEEs) were obtained dehydrating calcium alginate gel beads containing entrapped enzymes. A fructosyltransferase from Aspergillus aculeatus, present in Pectinex Ultra SP-L, was entrapped using this technique. The resulting DALGEEs were successfully tested both operating batchwise and in a continuous fixed-bed reactor for fructooligosaccharides (FOS) synthesis from sucrose. Interestingly, DALGEEs did not re-swell upon incubation in concentrated (600 g/L) sucrose solutions, probably due to the lowered water activity (aw) of such media. Confocal laser scanning microscopy of DALGEEs revealed that the enzyme molecules accumulated preferably in the shell of the particles. DALGEEs showed an approximately 30-fold higher volumetric activity (300 U/mL) compared with the calcium alginate gel beads. Moreover, a significant enhancement (40-fold) of the space-time-yield of fixed-bed bioreactors was observed when using DALGEEs as biocatalyst compared with gel beads (4030 g/day L of FOS vs. 103 g/day L). The operational stability of fixed-bed reactors packed with DALGEEs was extraordinary, providing a nearly constant FOS composition of the outlet during at least 700 h. It was also noticeable their resistance against microbial attack, even after long periods of storage at room temperature. The DALGEEs immobilisation strategy may also be useful for other biotransformations, in particular when they take place in low aw media. 相似文献