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921.
Maurizio Sajeva Francesca Grisafi Anna Maria Ferrarella Paolo D'italia 《Plant biosystems》2013,147(5):911-917
Abstract Starch was enzymatically assayed in the hypocotyls of radish (Raphanus sativus L.) seedlings grown in water or chloramphenicol (CAP) 1 × 104. CAP inhibits starch formation and its effect is related to the concentration. Both CAP- and water-grown hypocotyls are able to accumulate starch when sucrose is supplied in the medium, thus suggesting that the damage caused by CAP to the amyloplast is not irreversible. Apical segments of both water- and CAP- grown hypocotyls accumulate starch upon incubation in sucrose solutions while basal segments are unable to accumulate starch even in the presence of sucrose. The authors suggest that the basal segments are unable to perform sucrose uptake or that the amyloplast is incapable to starch synthesis. In any case the inability of the basal segment to perform sucrose uptake is independent of CAP. These findings confirm that the radish hypocotyls is not homogeneous along its axes. 相似文献
922.
Marta Grech Paolo Sartor Elizabet Estallo Francisco Ludue?a-Almeida Walter Almirón 《Memórias do Instituto Oswaldo Cruz》2013,108(6):772-777
The aims of this study were to characterise the ground-level larval habitats of
the mosquito Culex quinquefasciatus, to determine the
relationships between habitat characteristics and larval abundance and to
examine seasonal larval-stage variations in Córdoba city. Every two weeks for
two years, 15 larval habitats (natural and artificial water bodies, including
shallow wells, drains, retention ponds, canals and ditches) were visited and
sampled for larval mosquitoes. Data regarding the water depth, temperature and
pH, permanence, the presence of aquatic vegetation and the density of collected
mosquito larvae were recorded. Data on the average air temperatures and
accumulated precipitation during the 15 days prior to each sampling date were
also obtained. Cx. quinquefasciatus larvae were collected
throughout the study period and were generally most abundant in the summer
season. Generalised linear mixed models indicated the average air temperature
and presence of dicotyledonous aquatic vegetation as variables that served as
important predictors of larval densities. Additionally, permanent breeding sites
supported high larval densities. In Córdoba city and possibly in other highly
populated cities at the same latitude with the same environmental conditions,
control programs should focus on permanent larval habitats with aquatic
vegetation during the early spring, when the Cx.
quinquefasciatus population begins to increase. 相似文献
923.
924.
Walter Fratta Giampaolo Mereu Paolo Chessa Elisabetta Paglietti GianLuigi Gessa 《Life sciences》1976,18(10):1157-1165
The effect of different benzodiazepines on food intake was studied in cats which had been trained to eat their daily food within 3 hours, under conditions in which emotional factors were not present. When benzodiazepines were administered (at a dose ranging from 0.1 to 3 mg/Kg) before feeding, they increased both the total amount of food eaten and also the rate at which food was injested. When they were administered at the end of the feeding period, these compounds made the animals resume eating voraciously. The order of decreasing potency of the benzodiazepines tested was: oxazepam, N-methyl-lorazepam, diazepam, chlordiazepoxide, pinazepam, medazepam. Oxazepam (3 mg/Kg) stimulated maximally the food intake, even when administered up to 12 hours before feeding. Finally, oxazepam antagonized the anorexigenic effect of d-amphetamine, but did not influence amphetamine-induced hyperactivity and stereotyped behavior. 相似文献
925.
926.
Laura Pastorino Elena Dellacasa Mohamed R. Noor Tewfik Soulimane Paolo Bianchini Francesca D'Autilia Alexei Antipov Alberto Diaspro Syed A. M. Tofail Carmelina Ruggiero 《PloS one》2014,9(11)
Cell-sized polyelectrolyte capsules functionalized with a redox-driven proton pump protein were assembled for the first time. The interaction of polyelectrolyte microcapsules, fabricated by electrostatic layer-by-layer assembly, with cytochrome c oxidase molecules was investigated. We found that the cytochrome c oxidase retained its functionality, that the functionalized microcapsules interacting with cytochrome c oxidase were permeable and that the permeability characteristics of the microcapsule shell depend on the shell components. This work provides a significant input towards the fabrication of an integrated device made of biological components and based on specific biomolecular functions and properties. 相似文献
927.
928.
Ulteriore contributo alle conoscenze sul « Denti de cani » (X Haynaldoticum sardoum Meletti e Onnis)
Abstract Further data on « Denti de cani » (X Haynaldoticum sardoum Meletti e Onnis). – The authors defin the taxonomic position of « Denti de cani » (X Haynaldoticum sardoum Meletti e Onnis). It is characterized by the presence of two forms differentiated for morphological features and behaviour. 相似文献
929.
930.
Laura Andolfi Eugenia Bourkoula Elisa Migliorini Anita Palma Anja Pucer Miran Skrap Giacinto Scoles Antonio Paolo Beltrami Daniela Cesselli Marco Lazzarino 《PloS one》2014,9(11)
Active cell migration and invasion is a peculiar feature of glioma that makes this tumor able to rapidly infiltrate into the surrounding brain tissue. In our recent work, we identified a novel class of glioma-associated-stem cells (defined as GASC for high-grade glioma -HG- and Gasc for low-grade glioma -LG-) that, although not tumorigenic, act supporting the biological aggressiveness of glioma-initiating stem cells (defined as GSC for HG and Gsc for LG) favoring also their motility. Migrating cancer cells undergo considerable molecular and cellular changes by remodeling their cytoskeleton and cell interactions with surrounding environment. To get a better understanding about the role of the glioma-associated-stem cells in tumor progression, cell deformability and interactions between glioma-initiating stem cells and glioma-associated-stem cells were investigated. Adhesion of HG/LG-cancer cells on HG/LG-glioma-associated stem cells was studied by time-lapse microscopy, while cell deformability and cell-cell adhesion strengths were quantified by indentation measurements by atomic force microscopy and single cell force spectroscopy. Our results demonstrate that for both HG and LG glioma, cancer-initiating-stem cells are softer than glioma-associated-stem cells, in agreement with their neoplastic features. The adhesion strength of GSC on GASC appears to be significantly lower than that observed for Gsc on Gasc. Whereas, GSC spread and firmly adhere on Gasc with an adhesion strength increased as compared to that obtained on GASC. These findings highlight that the grade of glioma-associated-stem cells plays an important role in modulating cancer cell adhesion, which could affect glioma cell migration, invasion and thus cancer aggressiveness. Moreover this work provides evidence about the importance of investigating cell adhesion and elasticity for new developments in disease diagnostics and therapeutics. 相似文献