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1.
Knud IB Christensen 《Nordic Journal of Botany》1983,2(6):537-548
Crataegus curvisepala Lindm., C. laevigata (Poiret) DC. and C. monogyna Jacq. (Rosaceae) form hybrid complexes in Denmark due to introgression. C. palmstruchii Lindm. seems to be variously introgressed individuals of C. laevigata. C. eremitagensis Raunk., C. raavadensis Raunk. and C. schumacheri Raunk. apparently belong to C. curvisepala x laevigata. The delimitation between C. curvisepala x laevigata and C. laevigata x monogyna is discussed. 相似文献
2.
ZBARSKYIB 《Cell research》1998,8(2):99-103
The nonchromatin proteinous residue of the cell nucleus was revealed in our laboratory as early as in 1948 and then identified by light and electron microscopy as residual nucleoli,intranuclear network and nuclear envelope before 1960,This structure termed afterwards as “nuclear residue“,“nuclear skeleton“,“nuclear cage“,“nuclear carcass“etc.,was much later(in 1974) isolated,studied and entitled as “nuclear matrix“ by Berezney and Coffey,to whom the discovery of this residual structure is often wronly ascribed.The real history of nuclear matrix manifestation is reported in this paper. 相似文献
3.
Sara Da Pieve Sonia Calligaris Edmund Co Maria C. Nicoli Alejandro G. Marangoni 《Food biophysics》2010,5(3):211-217
The aim of the present research was to study the effect of shear on the crystallization behavior of monoglyceride organogels.
To this end, organogels were prepared by mixing cod liver oil and saturated monoglycerides at 80°C and then crystallizing
them at 20°C under shear rates ranging from 0 to 2,000 s−1. The organogels were characterized using polarized light microscopy, Cryo-SEM, and X-ray diffraction. The rheological properties
and the oil binding capacity of the different systems were also evaluated. Results obtained in this study showed that the
introduction of shear during organogel formation greatly affects structure at the nano, micro, and macro levels. Solidification
of the organogel under static conditions led to the formation of a strong gel network, with a high oil binding capacity. On
the contrary, shear processing during crystallization led to the formation of a weak gel network with a low oil binding capacity. 相似文献
4.
Marta Deganuto Laura Cesaratto Cristina Bellarosa Raffaella Calligaris Sandra Vilotti Giovanni Renzone Rossana Foti Andrea Scaloni Stefano Gustincich Franco Quadrifoglio Claudio Tiribelli Gianluca Tell 《Proteomics》2010,10(8):1645-1657
Unconjugated bilirubin (UCB) is a powerful antioxidant and a modulator of cell growth through the interaction with several signal transduction pathways. Although newborns develop a physiological jaundice, in case of severe hyperbilirubinemia UCB may become neurotoxic causing severe long‐term neuronal damages, also known as bilirubin encephalopathy. To investigate the mechanisms of UCB‐induced neuronal toxicity, we used the human neuroblastoma cell line SH‐SY5Y as an in vitro model system. We verified that UCB caused cell death, in part due to oxidative stress, which leads to DNA damage and cell growth reduction. The mechanisms of cytotoxicity and cell adaptation to UCB were studied through a proteomic approach that identified differentially expressed proteins involved in cell proliferation, intracellular trafficking, protein degradation and oxidative stress response. In particular, the results indicated that cells exposed to UCB undertake an adaptive response that involves DJ‐1, a multifunctional neuroprotective protein, crucial for cellular oxidative stress homeostasis. This study sheds light on the mechanisms of bilirubin‐induced neurotoxicity and might help to design a strategy to prevent or ameliorate the neuronal damages leading to bilirubin encephalopathy. 相似文献
5.
JUAN DIEGO IBÁÑEZ‐ÁLAMO MANUEL SOLER 《Biological journal of the Linnean Society. Linnean Society of London》2010,101(4):759-766
Urbanization, one of the most extreme land‐use alterations, is currently spreading, and the number of species confronting these changes is increasing. However, contradictory results of previous studies impede a clear interpretation of which selective pressure (nest predation or food limitation) is more important in urban habitats compared with natural situations, and whether birds can confront them by adjusting their life‐history strategies. We investigated life‐history syndromes of three common blackbird (Turdus merula) populations differing in their human influence (urban, rural, and woodland). We analysed daily nest predation and nestling starvation rates to assess the relative importance of these selection pressures in each habitat. Simultaneously, several life‐history traits were investigated to determine if T. merula seem adapted to their main source of selection. Food limitation was more important in the city, whereas nest predation was the most important selective force in the forest. The rural habitat was characterized by an intermediate influence of these two factors. Life‐history syndromes, as the covariation of a suite of traits, confirmed these results because T. merula seem well adapted to the main cause of selection in each habitat. Our results are consistent with urbanization imposing new challenges on birds, and that they adaptively respond to them. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101 , 759–766. 相似文献
6.
Cesaratto L Vascotto C D'Ambrosio C Scaloni A Baccarani U Paron I Damante G Calligaris S Quadrifoglio F Tiribelli C Tell G 《Free radical research》2005,39(3):255-268
Oxidative stress is a major pathogenetic event occurring in several liver disorders and is a major cause of liver damage due to Ischemia/Reperfusion (I/R) during liver transplantation. While several markers of chronic oxidative stress are well known, early protein targets of oxidative injury are not well defined. In order to identify these proteins, we used a differential proteomics approach to HepG2 human liver cells treated for 10 min with 500 microM H(2)O(2). This dose was sufficient to induce a slight decrease of total GSH and total protein thiol content without affecting cell viability. By performing Differential Proteomic analysis, by means of two-dimensional gel electrophoresis and MALDI-TOF mass spectrometry, we identified four proteins which resulted sensitive to H(2)O(2) treatment. The main changes were due to post-translational modifications of native polypeptides. Three of these proteins belong to the Peroxiredoxin family of hydroperoxide scavengers, namely PrxI, PrxII and PrxVI, that showed changes in their pI as result of overoxidation. Mass mapping experiments demonstrated the specific modification of peroxiredoxins active site thiol into sulphinic and/or sulphonic acid, thus explaining the increase in negative charge measured for these proteins. The oxidation kinetic of all peroxiredoxins was extremely rapid and sensitive, occurring at H(2)O(2) doses unable to affect the common markers of cellular oxidative stress. Recovery experiments demonstrated a quite different behaviour between 1-Cys and 2-Cys containing Prxs as their retroreduction features is concerned, thus suggesting a functional difference between different class of Prxs. The in vivo relevance of our study is demonstrated by the finding that overoxidation of PrxI occurs during I/R upon liver transplantation and is dependent on the time of warm ischemia. Our present data could be of relevance in setting up more standardized procedures to preserve organs for transplantations. 相似文献
7.
Sebastián Dante Calligaris Micaela Ricca Paulette Conget 《Journal of visualized experiments : JoVE》2013,(72)
Dobutamine is a β-adrenergic agonist with an affinity higher for receptor expressed in the heart (β1) than for receptors expressed in the arteries (β2). When systemically administered, it increases cardiac demand. Thus, dobutamine unmasks abnormal rhythm or ischemic areas potentially at risk of infarction. Monitoring of heart function during a cardiac stress test can be performed by either ecocardiography or cardiac catheterization. The latter is an invasive but more accurate and informative technique that the former.Cardiac stress test induced by dobutamine and monitored by cardiac catheterization accomplished as described here allows, in a single experiment, the measurement of the following hemodynamic parameters: heart rate (HR), systolic pressure, diastolic pressure, end-diastolic pressure, maximal positive pressure development (dP/dtmax) and maximal negative pressure development (dP/dtmin), at baseline conditions and under increasing doses of dobutamine.As expected, in normal mice we observed a dobutamine dose-related increase in HR, dP/dtmax and dP/dtmin. Moreover, at the highest dose tested (12 ng/g/min) the cardiac decompensation of high fat diet-induced obese mice was unmasked. 相似文献
8.
This research was addressed to develop transparent microemulsions as delivery system of lemon oil. To this aim, phase inversion temperature (PIT) method was employed. The effect of the surfactant Tween 80 content as well as lipid phase type and concentration (lemon oil, peanut oil and their mixtures) on microemulsion characteristics was studied. Transparent emulsions were obtained up to 1.3 and 7.5% (w/w) of lemon oil and peanut oil, respectively. Only by considering as lipid phase a mixture of lemon oil and peanut oil, it was possible to increase the delivering capacity of emulsions up to 15% of lemon oil (total oil phase 20%). Therefore, blending peanut oil rich in long chain fatty acids with lemon oil expanded the lipid phase loading capacity of microemulsions while maintaining particle size lower than 30 nm and thus system transparency. Microemulsions showed good dilutability in aqueous solutions simulating beverage formulations with different pH values. 相似文献
9.
Multidrug resistance associated protein 1 protects against bilirubin-induced cytotoxicity 总被引:2,自引:0,他引:2
Calligaris S Cekic D Roca-Burgos L Gerin F Mazzone G Ostrow JD Tiribelli C 《FEBS letters》2006,580(5):1355-1359
We have shown that multidrug resistance associated protein 1 (MRP1) mediates ATP-dependent extrusion of bilirubin, possibly limiting its potentially toxic accumulation in cells. To determine directly if Mrp1 protects cells against unconjugated bilirubin (UCB) toxicity, mouse embryo fibroblasts (MEF) were isolated from Mrp1 knockout (-/-) mice and their wild type (WT) (+/+) littermates. Compared to WT cells, cultured MEF (-/-) cells exposed to 40-140 nM unbound [H3]-bilirubin accumulated twice as much [H3]-bilirubin (P<0.01). This was associated with greater, dose-related cytotoxicity, assessed by the methylthiazoletetrazolium test, lactate dehydrogenase release and cellular ATP content. The data confirm that Mrp1 limits intracellular accumulation of UCB and thus decreases its cytotoxicity. 相似文献
10.
IB Masters MM Eastburn PW Francis R Wootton PV Zimmerman RS Ware AB Chang 《Respiratory research》2005,6(1):16