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31.
Chiara Salvesi Stefania Silvi Dennis Fiorini Serena Scortichini Gianni Sagratini Francesco A. Palermo Renato De Leone Nadaniela Egidi Lorella Fatone Carlo Cifani Amedeo Amedei Francesca Scocchera Mara Morici Beatrice Gatto Fausto Mannucci Valerio Valeriani Marco Malavasi Sara Servili Andrea Casula Andrea Cresci Ivano Corradetti Francesco Carpi Matteo Picciolini Maria Magdalena Coman Maria Cristina Verdenelli 《Journal of applied microbiology》2022,133(5):2941-2953
32.
Roveta Camilla Annibaldi Anna Domenichelli Federico Gregorin Chiara Gridelli Stefano Pantano Valentina Vagnoni Flavio Puce Stefania 《Aquatic Ecology》2022,56(3):631-637
Aquatic Ecology - Jellyfish blooms are an increasingly common event in our seas. Occurring via polyps’ asexual reproduction induced by human stresses, they represent a hazard for ecosystems... 相似文献
33.
Francesca Giampieri Md Soriful Islam Stefania Greco Massimiliano Gasparrini Tamara Y. Forbes Hernandez Giovanni Delli Carpini Stefano Raffaele Giannubilo Andrea Ciavattini Bruno Mezzetti Luca Mazzoni Franco Capocasa Mario Castellucci Maurizio Battino Pasquapina Ciarmela 《Journal of cellular physiology》2019,234(5):7622-7633
Uterine leiom yomas are benign tumors highly prevalent in reproductive women. In thecurrent study, initially, we aimed to screen five different strawberry cultivars (Alba, Clery, Portola, Tecla, and Romina) to identify efficient cultivars in terms of phytochemical characterization and biological properties by measuring phenolic and anthocyanin content as well as antioxidant capacity, and by measuring apoptotic rate and reactive oxygen species (ROS) production in uterine leiomyoma cells. Next, we focused on the most efficient ones, cultivar Alba (A) and Romina (R) as well as Romina anthocyanin (RA) fraction for their ability to regulate oxidative phosphorylation (oxygen consumption rate [OCR]) glycolysis (extracellular acidification rate [ECAR]), and also fibrosis. Leiomyoma and myometrial cells were treated with a methanolic extract of A and R (250 μg/ml) or with RA (50 μg/ml) for 48 hr to measure OCR and ECAR, as well as gene expression associated with fibrosis. In the leiomyoma cells, RA was more effective in inducing apoptosis and increasing intracellular ROS levels, followed by R and A. In myometrial cells, all strawberry treatments increased the cellular viability and decreased ROS concentrations. Leiomyoma cells showed also a significant decrease in ECAR, especially after RA treatment, while OCR was slightly increased in both myometrial and leiomyoma cells. R and RA treatment significantly decreased collagen 1A1, fibronectin, versican, and activin A messenger RNA expression in leiomyoma cells. In conclusion, this study suggests that Romina, or its anthocyanin fraction, can be developed as a therapeutic and/or preventive agent for uterine leiomyomas, confirming the healthy effects exerted by these fruits and their bioactive compounds. 相似文献
34.
Maria Raffaella Greco Emeline Bon Rosa Rubino Lorenzo Guerra Manuel Bernabe-Garcia Stefania Cannone Maria-Luisa Cayuela Loredana Ciaccia Séverine Marionneau-Lambot Thibauld Oullier Gaëlle Fromont Roseline Guibon Sébastien Roger Stephan Joel Reshkin Rosa Angela Cardone 《生物化学与生物物理学报:疾病的分子基础》2019,1865(1):26-37
Metastatic cancer cells are highly plastic for the expression of different tumor phenotype hallmarks and organotropism. This plasticity is highly regulated but the dynamics of the signaling processes orchestrating the shift from one cell phenotype and metastatic organ pattern to another are still largely unknown. The scaffolding protein NHERF1 has been shown to regulate the expression of different neoplastic phenotypes through its PDZ domains, which forms the mechanistic basis for metastatic organotropism. This reprogramming activity was postulated to be dependent on its differential phosphorylation patterns. Here, we show that NHERF1 phosphorylation on S279/S301 dictates several tumor phenotypes such as in vivo invasion, NHE1-mediated matrix digestion, growth and vasculogenic mimicry. Remarkably, injecting mice with cells having differential NHERF1 expression and phosphorylation drove a shift from the predominantly lung colonization (WT NHERF1) to predominately bone colonization (double S279A/S301A mutant), indicating that NHERF1 phosphorylation also acts as a signaling switch in metastatic organotropism. 相似文献
35.
Loredana R Barbara D Annamaria L Stefania T Maria MC Silvana F Piero A Marina P 《Molecular reproduction and development》2003,66(1):54-59
In the present paper we investigated the role played by apoptosis during oogenesis in the cartilaginous fish Torpedo marmorata. TEM, TUNEL and immunohistochemical techniques were employed to specifically reveal morphological and biochemical hallmarks of apoptosis in specimens from birth to sexual maturity. Data obtained demonstrate that apoptosis occurs in prefollicular oocyte selection, in maintaining the homeostasis of granulosa in healthy growing oocyte and in resorbing atretic follicles. In this respect, the involvement of apoptosis in Torpedo marmorata oogenesis closely parallels that found in mammals, thus confirming that strategies of germ cell selection among vertebrates have been evolutionarily preserved. 相似文献
36.
Francesco Loreto Michela Mannozzi Christophe Maris Pamela Nascetti Francesco Ferranti Stefania Pasqualini 《Plant physiology》2001,126(3):993-1000
Isoprene is formed in and emitted by plants and the reason for this apparent carbon waste is still unclear. It has been proposed that isoprene stabilizes cell and particularly chloroplast thylakoid membranes. We tested if membrane stabilization or isoprene reactivity with ozone induces protection against acute ozone exposures. The reduction of visible, physiological, anatomical, and ultrastructural (chloroplast) damage shows that clones of plants sensitive to ozone and unable to emit isoprene become resistant to acute and short exposure to ozone if they are fumigated with exogenous isoprene, and that isoprene-emitting plants that are sensitive to ozone do not suffer damage when exposed to ozone. Isoprene-induced ozone resistance is associated with the maintenance of photochemical efficiency and with a low energy dissipation, as indicated by fluorescence quenching. This suggests that isoprene effectively stabilizes thylakoid membranes. However, when isoprene reacts with ozone within the leaves or in a humid atmosphere, it quenches the ozone concentration to levels that are less or non-toxic for plants. Thus, protection from ozone in plants fumigated with isoprene may be due to a direct ozone quenching rather than to an induced resistance at membrane level. Irrespective of the mechanism, isoprene is one of the most effective antioxidants in plants. 相似文献
37.
Graziella Bellone Massimo Geuna Anna Carbone Stefania Silvestri Robin Foa Giorgio Emanuelli Lina Matera 《Journal of cellular physiology》1995,163(2):221-231
The pituitary hormone prolactin (Prl) is known to act as a local regulator of immune cell function, and Prl-binding receptors (Prl-R) have been described to share distinctive features with the members of the newly described cytokine/hemopoietin receptor superfamily. Here we show that the hormone can functionally interact with lineage-specific hemopoietic factors. When highly purified progenitor cells (CD34+ve) were seeded in semisolid methylcellulose cultures in the presence of interleukin (IL)-3, granulocyte-macrophage colony stimulating factor (GM-CSF), and erythropoietin (Epo), a selective enhancing effect of Prl on the formation of colony forming unit-granulocyte (CFU-G) and burst forming unit-erythroid (BFU-E) colonies was observed. The effect of the hormone was plotted as a bell shaped curve, with the optimal response at the supraphysiological concentration of 50 ng/ml. Limiting dilution analysis showed that Prl acted directly on hemopoietic progenitors. This was confirmed by the observation on the CD34+ve cells of Prl-binding sites reacting with the specific monoclonal antibodies (mAbs), U5 and PrR-7A. Immunoprecipitation of the metabolically labeled CD34+ve cells with the PrR-7A mAb revealed a structure of 43 kD under reducing conditions. Analysis of the early events associated with the Prl/Prl-R interaction showed an increased number of cells engaged in DNA and hemoglobin synthesis. Enhanced erythroid differentiation of CD34+ve cells in the presence of Prl was secondary to upmodulation of receptors for the lineage-specific factor Epo. Together these data demonstrate the existence of a functional interplay between Prl. and hemopoietic factors. © 1995 Wiley-Liss, Inc. 相似文献
38.
The Cercopithecini, or African guenon monkeys, are one of the most diverse clades of living primates and comprise the most species‐rich clade of Catarrhini. Species identity is announced by flamboyant coloration of the facial and genital regions and, more cryptically, by vigorous chromosomal rearrangements among taxa. Beneath the skin, however, these animals are skeletally conservative and show low levels of genetic sequence divergence consonant with recent divergence between congeneric species. The guenons clearly demonstrate that morphological, cytogenetic, and reproductive differentiation proceed at different rates during speciation. We review diverse kinds of data in an effort to understand this conundrum. 相似文献
39.
Gametogenesis of intergroup hybrids of hemiclonal frogs 总被引:1,自引:0,他引:1
Ragghianti M Bucci S Marracci S Casola C Mancino G Hotz H Guex GD Plötner J Uzzell T 《Genetical research》2007,89(1):39-45
European water frog hybrids Rana esculenta (R. ridibundaxR. lessonae) reproduce hemiclonally, by hybridogenesis: in the germ line they exclude the genome of one parental species and produce haploid gametes with an unrecombined genome of the other parental species. In the widespread L-E population system, both sexes of hybrids (E) coexist with R. lessonae (L). They exclude the lessonae genome and produce ridibunda gametes. In the R-E system, hybrid males coexist with R. ridibunda (R); they exclude either their ridibunda or their lessonae genome and produce sperm with a lessonae or with a ridibunda genome or a mixture of both kinds of sperm. We examined 13 male offspring, 12 of which were from crosses between L-E system and R-E system frogs. All were somatically hybrid. With one exception, they excluded the lessonae genome in the germ line and subsequently endoreduplicated the ridibunda genome. Spermatogonial metaphases contained a haploid or a diploid number of ridibunda chromosomes, identified through in situ hybridization to a satellite DNA marker, and by spermatocyte I metaphases containing a haploid number of ridibunda bivalents. The exception, an F1 hybrid between L-E system R. lessonae and R-E system R. ridibunda, was not hybridogenetic, showed no genome exclusion, and evidenced a disturbed gametogenesis resulting from the combination of two heterospecific genomes. None of the hybridogenetic hybrids showed any cell lines excluding the ridibunda genome, the pattern most frequent in hybrids of the R-E system, unique to that system, and essential for its persistence. A particular combination of R-E system lessonae and R-E system ridibunda genomes seems necessary to induce the R-E system type of hemiclonal gametogenesis. 相似文献