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521.
Antonia Concetta Elia Ambrosius Josef Martin Dörr Maria Cesarina Abete Marino Prearo 《Reviews in Fish Biology and Fisheries》2010,20(3):425-434
Tinca tinca were sampled seasonally from Lake Trasimeno in order to investigate the influence of heavy metal accumulation and changing
environmental parameters on the antioxidant responses in this species. Liver, gills and kidney of both sexes were analyzed
for total glutathione, catalase, glutathione peroxidase, glutathione reductase, glutathione S-transferase, glyoxalase I, glyoxalase
II, while muscle was analyzed for arsenic, lead, cadmium and mercury. The MRLs (maximum residue limits) set by actual regulation
were not exceeded for heavy metals, but a seasonal and sex-linked variability of antioxidant parameters was observed, and
major variations occurred especially in summer and autumn. In this shallow lake, heavy metal accumulation did not affect the
biochemical variations, which are rather due to the decreased water level inducing hyperoxia and hypoxia within 24 h, high
temperature and loss of mating and refuge areas. 相似文献
522.
Mario Lo Valvo Maria Concetta Rizzo Maria Pia Scarabello Nicolò Parrinello 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》1997,118(4):771-775
Electrophoretic patterns of seven enzyme systems and two nonenzymatic proteins, albumin and haemoglobin, representing 13 loci, have been investigated in six species of cardueline finches with Palearctic distribution. A new locus, SOD-3, has been characterized in this subfamily. The two nonenzymatic proteins turned out to be the best genetic markers. From the analysis of the genetic distances it emerges that the mean values between species are higher than those reported for other groups of birds. However, the same results were obtained for other species of the same subfamily native to North America. In both cases this result is probably due to a classification that disagrees with the real cardueline phylogeny. In the present study, the attribution of the Greenfinch to the genus Carduelis raises the mean value of distance between species. 相似文献
523.
Annamaria Merico Silvia Galafassi Jure Pikur & Concetta Compagno 《FEMS yeast research》2009,9(5):749-756
Yeasts belonging to the lineage that underwent whole-genome duplication (WGD) possess a good fermentative potential and can proliferate in the absence of oxygen. In this study, we analyzed the pre-WGD yeast Kluyveromyces lactis and its ability to grow under oxygen-limited conditions. Under these conditions, K. lactis starts to increase the glucose metabolism and accumulates ethanol and glycerol. However, under more limited conditions, the fermentative metabolism decreases, causing a slow growth rate. In contrast, Saccharomyces cerevisiae and Saccharomyces kluyveri in anaerobiosis exhibit almost the same growth rate as in aerobiosis. In this work, we showed that in K. lactis , under oxygen-limited conditions, a decreased expression of RAG1 occurred. The activity of glucose-6-phosphate dehydrogenase also decreased, likely causing a reduced flux in the pentose phosphate pathway. Comparison of related and characterized yeasts suggests that the behavior observed in K. lactis could reflect the lack of an efficient mechanism to maintain a high glycolytic flux and to balance the redox homeostasis under hypoxic conditions. This could be a consequence of a recent specialization of K. lactis toward living in a niche where the ethanol accumulation at high oxygen concentrations and the ability to survive at a low oxygen concentration do not represent an advantage. 相似文献
524.
Ronald J. Tallarida Ph.D. Roger W. Sevy Ph.D. M.D. Concetta Harakal Ph.D. 《Bulletin of mathematical biology》1970,32(1):65-69
According to the occupation theory of drug receptor interaction, the response is a functionf of the number of receptors occupied by drug molecules. Considerable controversy exists regarding assumptions about this function.
Without knowledge of the nature of the function, it is not possible to determine directly the rate constants, and hence the
affinity constant, in the reaction between the receptor and an agonist drug. Instead, indirect determinations involving the
use of antagonists have been employed, limiting the determination of affinity to those agents for which specific antagonists
exist. The present paper discusses a method for the direct determination of affinity of an agonist drug. It is a “relaxation
method,” i.e., the equilibrium is perturbed and the kinetics of the restoration process are studied. Assuming only thatf is non-decreasing and approximately linear over a limited domain of concentrations, it is shown that the change in response
obeys first order kinetics, permitting a determination of the rate constants from the time course of the restoration process. 相似文献
525.
526.
Concetta G.A. Marfella Yasuyuki Ohkawa Andrew H. Coles David S. Garlick Stephen N. Jones Anthony N. Imbalzano 《Journal of cellular physiology》2007,212(2):562-562
The original article to which this erratum refers was published in J Cell Physiol 2006; 209:162–171. 相似文献
527.
Prof. Francesco Galdiero Caterina Romano Carratelli Concetta Bentivoglio Immacolata Nuzzo Marilena Galdiero 《Current microbiology》1991,22(3):195-197
This study has assessed the changes in the polarization fluorescence of 1,6-diphenyl-1,3,5-hexatriene in the splenic membrane of mice treated with clindamycin, penicillin, cefoxitin, cefamandole, cephaloridine, tetracycline, and erythromycin. The data show that most of the antibiotics tested modified membrane activity, as was shown by the changes in membrane microviscosity parameters. 相似文献
528.
Agostina Pietrantoni Eleonora Dofrelli Antonella Tinari Maria Grazia Ammendolia Simona Puzelli Concetta Fabiani Isabella Donatelli Fabiana Superti 《Biometals》2010,23(3):465-475
Influenza is one of the main plagues worldwide. The statistical likelihood of a new pandemic outbreak, together with the alarming
emergence of influenza virus strains that are resistant to available antiviral medications, highlights the need for new antiviral
drugs. Lactoferrin, a 80 kDa bi-globular iron-binding glycoprotein, is a pleiotropic factor with potent antimicrobial and
immunomodulatory activities. Although the antiviral effect of lactoferrin is one of its major biological functions, the mechanism
of action is still under debate. In this research, we have analyzed the effect of bovine lactoferrin (bLf) on Influenza A
virus infection in vitro. Our results showed that (i) Influenza virus infected cells died as a result of apoptosis, (ii) bLf
treatment inhibited programmed cell death by interfering with function of caspase 3, a major virus-induced apoptosis effector,
and (iii) bLf efficiently blocked nuclear export of viral ribonucleoproteins so preventing viral assembly. These results provide
further insights on the antiviral activity of bLf and suggest novel strategies for treatment of Influenza virus infection. 相似文献
529.
530.
Vincenzo Brandolini Concetta Fiore Annalisa Maietti Paola Tedeschi Patrizia Romano 《World journal of microbiology & biotechnology》2007,23(4):581-586
A preliminary investigation on 20 Aglianico del Vulture commercial wines from the Basilicata region proved the existence of
a significant variability in total antioxidant capacity which can exert a potential impact on wine quality. Nineteen Saccharomyces cerevisiae strains were tested in Aglianico del Vulture on pilot scale fermentation and the experimental wines obtained were evaluated
for the antioxidant capacity, ethanol and total polyphenols. At the ninth day of fermentation the experimental wines had an
antioxidant capacity, measured by photochemiluminescence, between 2.88 and 6.25 mM of ascorbic acid equivalent, ethanol concentration,
measured by GC, between 5.49% and 10.99% and total polyphenols, determined by Folin Ciocalteau reagent, from 1153 to 1867 mg catechins/l.
After 12 days the total antioxidant capacity was increased in most wines but decreased in some wines. These results, statistically
analysed by principal component analysis, revealed a significant influence of S. cerevisiae strain on total antioxidant capacity and total polyphenols content of wine. 相似文献