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21.
Cadmium metabolism by rat liver endothelial and Kupffer cells. 总被引:1,自引:0,他引:1
The metabolism of cadmium was investigated in Wistar-rat liver non-parenchymal cells. Kupffer and endothelial cells, the major cell populations lining the sinusoidal tracts, were isolated by collagenase dispersion and purified by centrifugal elutriation. At 20 h after subcutaneous injection of the metal salt (1.5 mg of Cd/kg body weight), endothelial cells accumulated 2-fold higher concentrations of Cd than did Kupffer or parenchymal cells. Most of the Cd in non-parenchymal cells was associated with cytosolic metallothionein (MT), the low-Mr heavy-metal-binding protein(s). When MT was quantified in cytosols from cells isolated from control rats by a 203Hg competitive-binding assay, low levels were found to be present in Kupffer, endothelial and parenchymal cells. Cd injection significantly increased MT levels in all three cell types. The induction of MT synthesis was investigated in vitro by using primary monolayer cultures. The incorporation of [35S]cysteine into MT increased 47% over constitutive levels in endothelial-cell cultures after the addition of 0.8 microM-Cd2+ to the medium for 10 h. MT synthesis in Kupffer cells was not observed. The lack of MT synthesis by monolayer cultures of Kupffer cells in vitro was associated with a decreased capacity of these cells to accumulate heavy metals from the extracellular medium. This apparent decreased ability to transport metals did not reflect a general defect in either cellular function or metabolic activity, since isolated Kupffer cells incorporated [3H]leucine into protein at rates comparable with those shown by liver parenchymal cells and readily phagocytosed particles. 相似文献
22.
Thomas Tilling Ewa Wladykowski Antonio Virgilio Failla Pia Houdek Johanna M. Brandner Ingrid Moll 《Histochemistry and cell biology》2014,141(4):407-421
Merkel cells, the neurosecretory cells of skin, are essential for light-touch responses and may probably fulfill additional functions. Whether these cells derive from an epidermal or a neural lineage has been a matter of dispute for a long time. In mice, recent studies have clearly demonstrated an epidermal origin of Merkel cells. Given the differences in Merkel cell distribution between human and murine skin, it is, however, unclear whether the same holds true for human Merkel cells. We therefore attempted to gain insight into the human Merkel cell lineage by co-immunodetection of the Merkel cell marker protein cytokeratin 20 (CK20) with various proteins known to be expressed either in epidermal or in neural stem cells of the skin. Neither Sox10 nor Pax3, both established markers of the neural crest lineage, exhibited any cell co-labeling with CK20. By contrast, β1 integrin, known to be enriched in epidermal stem cells, was found in nearly 70 % of interfollicular epidermal and 25 % of follicular Merkel cells. Moreover, LRIG1, also enriched in epidermal stem cells, displayed significant co-immunolabeling with CK20 as well (approximately 20 % in the interfollicular epidermis and 7 % in the hair follicle, respectively). Further epidermal markers were detected in sporadic Merkel cells. Cells co-expressing CK20 with epidermal markers may represent a transitory state between stem cells and differentiated cells. β1 integrin is probably also synthesized by a large subset of mature Merkel cells. Summarizing, our data suggest that human Merkel cells may originate from epidermal rather than neural progenitors. 相似文献
23.
Luigi Mariani Roberta Alilla Gabriele Cola Giovanni Dal Monte Chiara Epifani Giovanna Puppi Failla Osvaldo 《International journal of biometeorology》2013,57(6):881-893
This paper aims to describe the Italian PHEnology Network (IPHEN), a cooperative project started in 2006 with the aim of producing nationwide maps of analysis and forecast of plants phenological stages mainly used to satisfy the needs of agriculture, health and environmental care. Iphen is a data processing system composed of the following main segments (a) collection of atmospheric and phenological data, (b) processing of data with suitable phenological and geo-statistical models and (c) phenological maps of analysis and forecast. In more detail, IPHEN maps of analysis (featuring phenological stages reached at the date of processing) are produced with models based on a Normal Heat Hours approach which weighs hourly air temperature effectiveness for plant phenological progression applied to national grids of hourly temperature derived from the operational agro-meteorological network of CRA-CMA. A correction scheme based on phenological surveys provided by volunteer observers is applied to the first guess maps of analysis to obtain final maps. Forecast maps (prediction of the days of occurrence of relevant phenological stages) are produced on the basis of GFS model medium range forecasts and climatic data. Freeware IPHEN maps for grapevine, common and Arizona cypress, black elder, olive and locust trees are broadcasted weekly on the CRA-CMA website. The positive operational results of IPHEN are testified by 150 maps broadcasted during the 2011 season for the above-mentioned species. The system performances and reliability have been analysed focusing on the analysis of phenological simulation errors and on the sensitivity of phenological maps to anomalous atmospheric circulation patterns. The error analysis shows that phenological models are characterized by advances/delays that justify the adoption of an observation based correction scheme. The sensitivity analysis highlights that the system is responsive to the effects of circulation blocking systems leading to phenological advances and delays. 相似文献
24.
We previously developed an in vitro model to estimate the relative bioavailability of carotenoids from a meal prepared using commercial baby foods. The general applicability of this model was tested using a stir-fried meal consisting of fresh spinach, fresh carrots, tomato paste, and vegetable oil. After in vitro digestion of the cooked meal, the aqueous fraction was separated from residual oil droplet and solids by centrifugation to quantify micellarized carotenoids. The percentages of lutein, lycopene, α-carotene, and β-carotene transferred from the meal to the micellar fraction were 29.0 ± 0.6, 3.2 ± 0.1, 14.7 ± 0.3, and 16.0 ± 0.4, respectively. Carotenoid transfer from the meal to the aqueous fraction was inhibited when bile extract was omitted from the intestinal phase of digestion. The bioavailability of the micellarized carotenoids was validated using differentiated cultures of Caco-2 human intestinal cells. All four carotenoids were accumulated in a linear manner throughout a 6-hr incubation period. Metabolic integrity was not compromised by exposure of cultures to the diluted aqueous fraction from the digested meal. The addition of 500 μmol/L α-tocopherol to test medium significantly improved the stability of the micellar carotenoids within the tissue culture environment. These results support the utility of the in vitro digestion procedure for estimating the bioavailability of carotenoids from foods and meals. 相似文献
25.
L. Mariani S. G. Parisi G. Cola O. Failla 《International journal of biometeorology》2012,56(6):1123-1134
Atmospheric variables play a fundamental role in driving man-managed ecosystems and more specifically in agro-ecosystems, determining the quantity and quality of crop production. On the other hand, climate variability can be seen as the superimposition of gradual and abrupt changes. This paper is focused on European surface air temperature in the period 1951–2010. Analysis of this dataset identified breakpoints that define two homogeneous sub-periods: 1951–1987 and 1988–2010. Thermal resources for crops were analyzed adopting a “normal heat hours” approach. Computation highlighted a general increase in thermal resources in the European continent for crop groups II and III (C3 and C4 plants adapted to high or moderate temperatures), while a decline of thermal resources for crop group I (cold adapted C3) was highlighted in the Mediterranean area. The climate variability justifies a change in the potential latitudinal limits of different groups of crops, representing a fundamental step for crop adaptation to climate change. 相似文献
26.
F. Grassi M. Labra S. Imazio R. Ocete Rubio O. Failla A. Scienza F. Sala 《Conservation Genetics》2006,7(6):837-845
The distribution of Vitis vinifera subsp. silvestris, the wild grapevine subspecies of Vitis vinifera L., has been dramatically reduced in its major sites of diffusion, at first by the spread, over the last 150 years, of pathogens from North America and, more recently, with fragmentation of habitat and disbranching by humans. In this work, 418 wild grapevine samples, belonging to 78 populations, were collected in their main Mediterranean distribution areas, including the Caucasus area, and the extent of their genetic variability evaluated by analysing plastid microsatellite DNA polymorphism. Results show low haplotype diversity value, with five haplotypes detected within the analysed populations. The highest within-population haplotypic diversity, with the presence of all five detected haplotypes, was found in the Caucasus regions and in the central regions of Italy. The distribution of all detected haplotypes suggests the Caucasian region as the possible center of origin of Vitis vinifera subsp. silvestris. A principal plastid lineage was found to be fixed in several locations, in the Northernmost European countries and in the Southern island of Sardinia. These results draw attention to two different refugium sites in the Mediterranean basin and suggest that conservation priority should be given to grapevine populations still preserved in hotspots of these regions. 相似文献
27.
28.
The synthesis of prodigiosin by non-proliferating cells of Serratia marcescens was examined in the presence of a wide range of concentrations of inorganic phosphate (Pi). A high elevation of pigment formation was obtained at less than or equal to 0.3 mM, and a broader but much lower elevation was obtained at 10 to 250 mM Pi. The synthesis of two immediate precursors of the pitment also was inhibited by Pi. The mechanism of action of Pi did not involve changes in pH or accumulation of the trace metal nutrient iron or zinc. Inhibition was most pronounced when Pi was added to the induction system before the onset of pigment formation. The inhibitor also diminished the burst of alkaline phosphatase activity that occurred in the period between the start of induction and appearance of prodigiosin. 相似文献
29.
30.
Giulia Francesca Cifuni Andrea Amici Michela Contò Paolo Viola Sebastiana Failla 《European Journal of Wildlife Research》2014,60(3):519-526
This study examines the influence of hunting methods on the colour and lipid oxidation state of meat from wild boar (Sus scrofa) and fallow deer (Dama dama). In addition, the feasibility of using visible reflectance spectra (360 to 740 nm) to predict the lipid oxidation of meat was evaluated. A total of 25 wild boars and 14 fallow deer were hunted with two different methods, dog-driven hunting (DH) and harvest culling (HC), that imply different animal stresses before shooting. Lipid oxidation increased in the meat from both species, which had been frozen for 3 months. The increase was higher in the DH group than the HC group (P?<?0.05). Our results confirm the importance of hunting stress on meat quality and lipid stability. The multivariate regression analysis showed a high correlation (R 2?=?0.968) between the predicted and measured thiobarbituric acid-reactive substances (TBARS) values, suggesting that visible spectroscopy should prove useful for predicting meat oxidation. 相似文献