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891.
Giulia Maurizi Antonella Poloni Domenico Mattiucci Spartaco Santi Angela Maurizi Valerio Izzi Angelica Giuliani Stefania Mancini Maria Cristina Zingaretti Jessica Perugini Ilenia Severi Massimo Falconi Marco Vivarelli Maria Rita Rippo Silvia Corvera Antonio Giordano Pietro Leoni Saverio Cinti 《Journal of cellular physiology》2017,232(10):2887-2899
892.
A2A‐D2 receptor–receptor interaction modulates gliotransmitter release from striatal astrocyte processes
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893.
New data on morphology and ultrastructure of skin photophores in the deep‐sea squid Histioteuthis bonnellii (Férussac, 1834), Cephalopoda: Histioteuthidae
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894.
Ilenia Siciliano Pietro Bosio Giovanna Gilardi Maria Lodovica Gullino Angelo Garibaldi 《Mycotoxin Research》2017,33(2):139-146
The behavior of Myrothecium verrucaria, artificially inoculated on spinach, was studied under seven different temperature conditions (from 5 to 35 °C) and under eight different combinations of temperature and CO2 concentration (14–30 °C and 775–870 or 1550–1650 mg/m3). The isolate used for this study was growing well on spinach, and the mycotoxins verrucarin A and roridin E were produced under all tested temperature and CO2 conditions. The maximum levels of verrucarin A (18.59 ng/g) and roridin E (49.62 ng/g) were found at a temperature of 26–30 °C and a CO2 level of 1550–1650 mg/m3. Rises in temperature as well as in temperature and CO2 concentrations had a significant effect by increasing Myrothecium leaf spots on spinach. The biosynthesis of verrucarin A was significantly increased at the highest temperature (35 °C), while roridin E was influenced by the CO2 concentration. These results show that a positive correlation between climate condition and macrocyclic trichothecene production is possible. However, because of the ability of M. verrucaria to produce mycotoxins, an increase in temperature could induce the spread of M. verrucaria in temperate regions; this pathogen may gain importance in the future. 相似文献
895.
Roberto Würth Federica Barbieri Alessandra Pattarozzi Germano Gaudenzi Federico Gatto Pietro Fiaschi Jean-Louis Ravetti Gianluigi Zona Antonio Daga Luca Persani Diego Ferone Giovanni Vitale Tullio Florio 《Molecular neurobiology》2017,54(7):4879-4895
The presence and functional role of tumor stem cells in benign tumors, and in human pituitary adenomas in particular, is a debated issue that still lacks a definitive formal demonstration. Fifty-six surgical specimens of human pituitary adenomas were processed to establish tumor stem-like cultures by selection and expansion in stem cell-permissive medium or isolating CD133-expressing cells. Phenotypic and functional characterization of these cells was performed (1) ex vivo, by immunohistochemistry analysis on paraffin-embedded tissues; (2) in vitro, attesting marker expression, proliferation, self-renewal, differentiation, and drug sensitivity; and (3) in vivo, using a zebrafish model. Within pituitary adenomas, we identified rare cell populations expressing stem cell markers but not pituitary hormones; we isolated and expanded in vitro these cells, obtaining fibroblast-free, stem-like cultures from 38 pituitary adenoma samples. These cells grow as spheroids, express stem cell markers (Oct4, Sox2, CD133, and nestin), show sustained in vitro proliferation as compared to primary cultures of differentiated pituitary adenoma cells, and are able to differentiate in hormone-expressing pituitary cells. Besides, pituisphere cells, apparently not tumorigenic in mice, engrafted in zebrafish embryos, inducing pro-angiogenic and invasive responses. Finally, pituitary adenoma stem-like cells express regulatory pituitary receptors (D2R, SSTR2, and SSTR5), whose activation by a dopamine/somatostatin chimeric agonist exerts antiproliferative effects. In conclusion, we provide evidence that human pituitary adenomas contain a subpopulation fulfilling biological and phenotypical signatures of tumor stem cells that may represent novel therapeutic targets for therapy-resistant tumors. 相似文献
896.
Pietro Milanesi Frank Thomas Breiner Felice Puopolo Rolf Holderegger 《Ecography》2017,40(12):1359-1368
Europe is currently being re‐colonized by large carnivore species such as brown bear Ursus arctos, Eurasian lynx Lynx lynx and grey wolf Canis lupus. Approximately one‐third of Europe currently hosts at least one of these large carnivore species: they show permanent occurrence in some regions and sporadic occurrence without reproduction in others. We investigated potential future range expansions of these three large carnivores using three different analyses. First, we compared niche overlap between the historical, current permanent and current sporadic occurrences using n‐dimensional hypervolumes. Second, we identified the environmental variables that best explain differences between current sporadic and permanent occurrences through multi‐model inference. Third, we projected permanent occurrences into the future across a range of land‐use change scenarios. We also determined future refuges (i.e. sub‐optimal habitat in the environmental model, good habitat in the human disturbance model) and ecological traps (i.e. good habitat in the environmental model, sub‐optimal habitat in the human disturbance model). In the three large carnivore species, ecological niche overlap was higher between historical and current permanent occurrences than between historical and current sporadic occurrences, and we also found low ecological niche overlap between current permanent and sporadic occurrences. Between 20 and 24% (corresponding to 86 800 to 173 200 km2) of the current sporadic occurrences could result in permanent settlement of large carnivores in the year 2040, while 17–24% (corresponding to 122 200 to 104 100 km2) and 2.7–4.6% (corresponding to 11 800 to 28 400 km2) of the current sporadic occurrences are likely to become refuges and ecological traps, respectively. Factors affecting range expansion are human activities, which were negatively related to permanent occurrences of all three species. In light of our results, human‐dominated European landscapes provide ample space for the future recolonization of large carnivores. 相似文献
897.
A high susceptibility to redox imbalance of the transmissible stages of Plasmodium falciparum revealed with a luciferase‐based mature gametocyte assay
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Giulia Siciliano T.R. Santha Kumar Roberta Bona Grazia Camarda Maria Maddalena Calabretta Luca Cevenini Elisabeth Davioud‐Charvet Katja Becker Andrea Cara David A. Fidock Pietro Alano 《Molecular microbiology》2017,104(2):306-318
The goal to prevent Plasmodium falciparum transmission from humans to mosquitoes requires the identification of targetable metabolic processes in the mature (stage V) gametocytes, the sexual stages circulating in the bloodstream. This task is complicated by the apparently low metabolism of these cells, which renders them refractory to most antimalarial inhibitors and constrains the development of specific and sensitive cell‐based assays. Here, we identify and functionally characterize the regulatory regions of the P. falciparum gene PF3D7_1234700, encoding a CPW‐WPC protein and named here Upregulated in Late Gametocytes (ULG8), which we have leveraged to express reporter genes in mature male and female gametocytes. Using transgenic parasites containing a pfULG8‐luciferase cassette, we investigated the susceptibility of stage V gametocytes to compounds specifically affecting redox metabolism. Our results reveal a high sensitivity of mature gametocytes to the glutathione reductase inhibitor and redox cycler drug methylene blue (MB). Using isobologram analysis, we find that a concomitant inhibition of the parasite enzyme glucose‐6‐phosphate dehydrogenase‐6‐phosphogluconolactonase, a key component of NADPH synthesis, potently synergizes MB activity. These data suggest that redox metabolism and detoxification activity play an unsuspected yet vital role in stage V gametocytes, rendering these cells exquisitely sensitive to decreases in NADPH concentration. 相似文献
898.
Sonia Del Prete Daniela Vullo Pietro Di Fonzo Sameh M. Osman Zeid AlOthman William A. Donald Claudiu T. Supuran Clemente Capasso 《Bioorganic & medicinal chemistry letters》2017,27(3):490-495
A new γ-carbonic anhydrase (CA, EC 4.1.1.1) was cloned and characterized kinetically in the genome of the bacterial pathogen Burkholderia pseudomallei, the etiological agent of melioidosis, an endemic disease of tropical and sub-tropical regions of the world. The catalytic activity of this new enzyme, BpsCAγ, is significant with a kcat of 5.3 × 105 s?1 and kcat/Km of 2.5 × 107 M?1 × s?1 for the physiologic CO2 hydration reaction. The inhibition constant value for this enzyme for 39 sulfonamide inhibitors was obtained. Acetazolamide, benzolamide and metanilamide were the most effective (KIs of 149–653 nM) inhibitors of BpsCAγ activity, whereas other sulfonamides/sulfamates such as ethoxzolamide, topiramate, sulpiride, indisulam, sulthiame and saccharin were active in the micromolar range (KIs of 1.27–9.56 μM). As Burkholderia pseudomallei is resistant to many classical antibiotics, identifying compounds that interfere with crucial enzymes in the B. pseudomallei life cycle may lead to antibiotics with novel mechanisms of action. 相似文献
899.
Emanuela Galliera Monica Gioia Marazzi Carmine Gazzaruso Pietro Gallotti Adriana Coppola Tiziana Montalcini Arturo Pujia Massimiliano M. Corsi Romanelli 《Immunity & ageing : I & A》2017,14(1):13
Background
Osteoporosis is a systemic metabolic disease based on age-dependent imbalance between the rates of bone formation and bone resorption. Recent studies on the pathogenesis of this disease identified that bone remodelling impairment, at the base of osteoporotic bone fragility, could be related to protein glycation, in association to oxidative stress. The glycation reactions lead to the generation of glycation end products (AGEs) which, in turn, accumulates into bone, where they binds to the receptor for AGE (RAGE). The aim of this study is to investigate the potential role of circulating sRAGE in osteoporosis, in particular evaluating the correlation of sRAGE with the fracture risk, in association with bone mineral density, the fracture risk marker FGF23, and lipid metabolism.Results
Circulating level of soluble RAGE correlate with osteopenia and osteoporosis level. Serum sRAGE resulted clearly associated on the one hand to bone fragility and, on the other hand, with BMI and leptin. sRAGE is particularly informative because serum sRAGE is able to provide, as a single marker, information about both the aspects of osteoporotic disease, represented by bone fragility and lipid metabolism.Conclusions
The measure serum level of sRAGE could have a potential diagnostic role in the monitoring of osteoporosis progression, in particular in the evaluation of fracture risk, starting from the prevention and screening stage, to the osteopenic level to osteoporosis.900.
Pietro Cattaneo Julia Santiago Antia Rodriguez‐Villalon Michael Hothorn Christian S Hardtke 《EMBO reports》2017,18(8):1367-1381
Arabidopsis root development is orchestrated by signaling pathways that consist of different CLAVATA3/EMBRYO SURROUNDING REGION (CLE) peptide ligands and their cognate CLAVATA (CLV) and BARELY ANY MERISTEM (BAM) receptors. How and where different CLE peptides trigger specific morphological or physiological changes in the root is poorly understood. Here, we report that the receptor‐like protein CLAVATA 2 (CLV2) and the pseudokinase CORYNE (CRN) are necessary to fully sense root‐active CLE peptides. We uncover BAM3 as the CLE45 receptor in the root and biochemically map its peptide binding surface. In contrast to other plant peptide receptors, we found no evidence that SOMATIC EMBRYOGENESIS RECEPTOR KINASE (SERK) proteins act as co‐receptor kinases in CLE45 perception. CRN stabilizes BAM3 expression and thus is required for BAM3‐mediated CLE45 signaling. Moreover, protophloem‐specific CRN expression complements resistance of the crn mutant to root‐active CLE peptides, suggesting that protophloem is their principal site of action. Our work defines a genetic framework for dissecting CLE peptide signaling and CLV/BAM receptor activation in the root. 相似文献