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941.
The phototransduction enzymatic cascade in cones is less understood than in rods, and the zebrafish is an ideal model with which to investigate vertebrate and human vision. Therefore, here, for the first time, the zebrafish green cone photoresponse is characterized also to obtain a firm basis for evaluating how it is modulated by exogenous molecules. To this aim, a powerful method was developed to obtain long-lasting recordings with low access resistance, employing pressure-polished patch pipettes. This method also enabled fast, efficient delivery of molecules via a perfusion system coupled with pulled quartz or plastic perfusion tubes, inserted very close to the enlarged pipette tip. Sub-saturating flashes elicited responses in different cells with similar rising phase kinetics but with very different recovery kinetics, suggesting the existence of physiologically distinct cones having different Ca2+ dynamics. Theoretical considerations demonstrate that the different recovery kinetics can be modelled by simulating changes in the Ca2+-buffering capacity of the outer segment. Importantly, the Ca2+-buffer action preserves the fast response rising phase, when the Ca2+-dependent negative feedback is activated by the light-induced decline in intracellular Ca2+. 相似文献
942.
Giuditta Fiorella Schiavano Mauro De Santi Giorgio Brandi Mirco Fanelli Anahi Bucchini Laura Giamperi Giovanna Giomaro 《PloS one》2015,10(8)
Purpose
The aim of this study was to evaluate the antiproliferative activity in breast cancer cells and the inhibition of tumorigenesis in pre-neoplastic cells of a new apple cultivar with reddish pulp, called the Pelingo apple.Methods
The antiproliferative activity was evaluated in MCF-7 and MDA-MB-231 human breast cancer cells. The inhibition of tumorigenesis was performed in JB6 promotion-sensitive (P+) cells.Results
Results showed that Pelingo apple juice is characterized by a very high polyphenol content and strongly inhibited breast cancer cell proliferation. Its antiproliferative activity was found to be higher than the other five apple juices tested. Pelingo juice induced cell accumulation in the G2/M phase of the cell cycle and autophagy through overexpression of p21, inhibition of extracellular signal-regulated kinases 1/2 (ERK1/2) activity and an increase in lipidated microtubule-associated protein-1 light chain-3 beta (LC3B). Remarkably, Pelingo juice inhibited the 12-o-tetra-decanoyl-phorbol-13-acetate (TPA)-induced tumorigenesis of JB6 P+ cells, suppressing colony formation in semi-solid medium and TPA-induced ERK1/2 phosphorylation.Conclusions
Our data indicate that the Pelingo apple is rich in food components that can markedly inhibit in vitro tumorigenesis and growth of human breast cancer cells and could provide natural bioactive non-nutrient compounds, with potential chemopreventive activity. 相似文献943.
Giorgio Bernardi 《PloS one》2015,10(11)
How the same DNA sequences can function in the three-dimensional architecture of interphase nucleus, fold in the very compact structure of metaphase chromosomes and go precisely back to the original interphase architecture in the following cell cycle remains an unresolved question to this day. The strategy used to address this issue was to analyze the correlations between chromosome architecture and the compositional patterns of DNA sequences spanning a size range from a few hundreds to a few thousands Kilobases. This is a critical range that encompasses isochores, interphase chromatin domains and boundaries, and chromosomal bands. The solution rests on the following key points: 1) the transition from the looped domains and sub-domains of interphase chromatin to the 30-nm fiber loops of early prophase chromosomes goes through the unfolding into an extended chromatin structure (probably a 10-nm “beads-on-a-string” structure); 2) the architectural proteins of interphase chromatin, such as CTCF and cohesin sub-units, are retained in mitosis and are part of the discontinuous protein scaffold of mitotic chromosomes; 3) the conservation of the link between architectural proteins and their binding sites on DNA through the cell cycle explains the “mitotic memory” of interphase architecture and the reversibility of the interphase to mitosis process. The results presented here also lead to a general conclusion which concerns the existence of correlations between the isochore organization of the genome and the architecture of chromosomes from interphase to metaphase. 相似文献
944.
Xiomara Calderón-Colón Giorgio Raimondi Jason J. Benkoski Julia B. Patrone 《Journal of visualized experiments : JoVE》2015,(105)
Nanoparticle-based delivery vehicles have shown great promise for intracellular targeting applications, providing a mechanism to specifically alter cellular signaling and gene expression. In a previous investigation, the synthesis of ultra-small solid lipid nanoparticles (SLNs) for topical drug delivery and biomarker detection applications was demonstrated. SLNs are a well-studied example of a nanoparticle delivery system that has emerged as a promising drug delivery vehicle. In this study, SLNs were loaded with a fluorescent dye and used as a model to investigate particle-cell interactions. The phase inversion temperature (PIT) method was used for the synthesis of ultra-small populations of biocompatible nanoparticles. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenylphenyltetrazolium bromide (MTT) assay was utilized in order to establish appropriate dosing levels prior to the nanoparticle-cell interaction studies. Furthermore, primary human dermal fibroblasts and mouse dendritic cells were exposed to dye-loaded SLN over time and the interactions with respect to toxicity and particle uptake were characterized using fluorescence microscopy and flow cytometry. This study demonstrated that ultra-small SLNs, as a nanoparticle delivery system, are suitable for intracellular targeting of different cell types. 相似文献
945.
Domenica Scumaci Francesca Trimboli Ludovica Dell’Aquila Antonio Concolino Giusi Pappaianni Laura Tammè Giorgio Vignola Alessia Luciani Daniela Morelli Giovanni Cuda Andrea Boari Domenico Britti 《PloS one》2015,10(2)
The aim of this study was to shed light in to the complexity of the ovine colostrum proteome, with a specific focus on the low abundance proteins. The ovine colostrum is characterized by a few dominating proteins, as the immunoglobulins, but it also contains less represented protein species, equally important for the correct development of neonates. Ovine colostrum, collected immediately after lambing, was separated by 1D SDS-PAGE. Proteins bands were digested with trypsin and the resulting peptides were analyzed by LC-MS/MS. On the basis of the Swiss-Prot database, a total of 343 unique proteins were identified. To our knowledge, this study represents the most comprehensive analysis of ovine colostrum proteome. 相似文献
946.
Carlo Peretto Julie Arnaud Jacopo Moggi-Cecchi Giorgio Manzi Sébastien Nomade Alison Pereira Christophe Falguères Jean-Jacques Bahain Dominique Grimaud-Hervé Claudio Berto Benedetto Sala Giuseppe Lembo Brunella Muttillo Rosalia Gallotti Ursula Thun Hohenstein Carmela Vaccaro Mauro Coltorti Marta Arzarello 《PloS one》2015,10(10)
Isernia La Pineta (south-central Italy, Molise) is one of the most important archaeological localities of the Middle Pleistocene in Western Europe. It is an extensive open-air site with abundant lithic industry and faunal remains distributed across four stratified archaeosurfaces that have been found in two sectors of the excavation (3c, 3a, 3s10 in sect. I; 3a in sect. II). The prehistoric attendance was close to a wet environment, with a series of small waterfalls and lakes associated to calcareous tufa deposits. An isolated human deciduous incisor (labelled IS42) was discovered in 2014 within the archaeological level 3 coll (overlying layer 3a) that, according to new 40Ar/39Ar measurements, is dated to about 583–561 ka, i.e. to the end of marine isotope stage (MIS) 15. Thus, the tooth is currently the oldest human fossil specimen in Italy; it is an important addition to the scanty European fossil record of the Middle Pleistocene, being associated with a lithic assemblage of local raw materials (flint and limestone) characterized by the absence of handaxes and reduction strategies primarily aimed at the production of small/medium-sized flakes. The faunal assemblage is dominated by ungulates often bearing cut marks. Combining chronology with the archaeological evidence, Isernia La Pineta exhibits a delay in the appearance of handaxes with respect to other European Palaeolithic sites of the Middle Pleistocene. Interestingly, this observation matches the persistence of archaic morphological features shown by the human calvarium from the Middle Pleistocene site of Ceprano, not far from Isernia (south-central Italy, Latium). In this perspective, our analysis is aimed to evaluate morphological features occurring in IS42. 相似文献
947.
948.
Giorgio Walter Canonica Marta Bartezaghi Raffaele Marino Laura Rigoni 《Clinical and molecular allergy : CMA》2015,13(1)
Background
We designed the PROXIMA study (Patient-Reported Outcomes and Xolair® In the Management of Asthma) to determine the proportion of patients with severe asthma sensitive to perennial allergens, and to evaluate asthma control and treatment adherence up to 12 months in patients treated with omalizumab in Italian population. In addition, an ancillary study was designed to explore protein biomarkers and characterize them in relation to severe allergic asthma and treatment effects by proteomic approach.Methods
PROXIMA is an observational, multicenter, cross-sectional and prospective cohort study conducted at 25 centers in Italy, in outpatient settings. The study consists of two phases: 1) a cross-sectional phase plans to enroll 600 patients with severe allergic asthma, in step 4 therapy as per GINA guidelines, aged ≥18 years, needing a step up in therapy, and 2) a longitudinal phase on patients who will start omalizumab add-on therapy per clinician’s judgment at baseline visit (approximately 180–240 patients). The primary variable of the cross-sectional phase is the proportion of patients with severe asthma presenting with perennial form of allergy (skin prick test or in vitro test). The primary variable of longitudinal phase is proportion of patients who achieve disease control (assessed by Asthma Control Questionnaire [ACQ]) with omalizumab at 6 months, and maintain it at 12 months. Secondary variables are patient compliance to omalizumab, patient-reported perception of cognitive and emotional impact of the illness, assessed by Brief Illness Perception Questionnaire (Brief IPQ) and the health related quality of life evaluated by the EuroQoL 5D-3 L (EQ-5D-3 L). Safety endpoints will be recorded during the course of the study. Patients participating in the longitudinal phase will be enrolled for ancillary study if they provide additional informed consent. Protein species in complex mixtures will be identified using innovative MudPIT (Multidimensional Protein Identification Technology) method.Conclusions
The results of this observational study will provide estimate of patient population allergic to perennial allergens in Italy and information on patient-reported outcomes with omalizumab therapy in a real-world setting. The exploratory proteomic analysis on asthma biomarkers could eventually provide new data to identify responder patients to anti IgE therapy. 相似文献949.
950.