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61.
Perrone Maria Rita Romano Salvatore De Maria Giuseppe Tundo Paolo Bruno Anna Rita Tagliaferro Luigi Maffia Michele Fragola Mattia 《Aerobiologia》2022,38(3):391-412
Aerobiologia - The SARS-CoV-2 presence and the bacterial community profile in air samples collected at the Intensive Care Unit (ICU) of the Operational Unit of Infectious Diseases of Santa Caterina... 相似文献
62.
Giacomo Zaccone John Maina Antonino Germanà Giuseppe Montalbano Gioele Capillo Luisa Aragona Michał J. Kuciel Eugenia Rita Lauriano José M. Icardo 《Acta zoologica》2019,100(2):160-166
Available studies that have examined O2 sensing in fish have indicated that oxygen-sensitive neuroepithelial cells (NECs) are O2 sensors in the gills and initiate cardiorespiratory reflexes in aquatic vertebrates. This is the first study describing the occurrence of NECs in accessory respiratory organs in the air-breathing catfish Clarias gariepinus. Immunocytochemical stainings with specific neuronal markers such as nNOS, VAchT, 5-HT and TH have been shown to be very useful for location and distribution of these cells in the gill fans and suprabranchial chamber that take origin from the transformation of the gill tissue. But the response of these putative O2 chemoreceptors, their role in the respiratory reflexes and their innervation await investigation. 相似文献
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Genomic Resources Development Consortium Mariella Baratti Federica Cattonaro Tiziana Di Lorenzo Diana Maria Paola Galassi Valentina Iannilli Alessio Iannucci Just Jensen Peter Foged Larsen Rasmus O. Nielsen Cino Pertoldi Dragos Postolache Jose Martin Pujolar Ettore Randi Aritz Ruiz‐Gonzalez Janne Pia Thirstrup Giovanni Giuseppe Vendramin Andrzej Zalewski 《Molecular ecology resources》2015,15(2):458-459
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Elisabetta Panza Paola De Cicco Chiara Armogida Giosuè Scognamiglio Vincenzo Gigantino Gerardo Botti Domenico Germano Maria Napolitano Andreas Papapetropoulos Mariarosaria Bucci Giuseppe Cirino Angela Ianaro 《Pigment cell & melanoma research》2015,28(1):61-72
In humans, two main metabolic enzymes synthesize hydrogen sulfide (H2S): cystathionine γ lyase (CSE) and cystathionine β synthase (CBS). A third enzyme, 3‐mercaptopyruvate sulfurtransferase (3‐MST), synthesizes H2S in the presence of the substrate 3‐mercaptopyruvate (3‐MP). The immunohistochemistry analysis performed on human melanoma samples demonstrated that CSE expression was highest in primary tumors, decreased in the metastatic lesions and was almost silent in non‐lymph node metastases. The primary role played by CSE was confirmed by the finding that the overexpression of CSE induced spontaneous apoptosis of human melanoma cells. The same effect was achieved using different H2S donors, the most active of which was diallyl trisulfide (DATS). The main pro‐apoptotic mechanisms involved were suppression of nuclear factor‐κB activity and inhibition of AKT and extracellular signal‐regulated kinase pathways. A proof of concept was obtained in vivo using a murine melanoma model. In fact, either l ‐cysteine, the CSE substrate, or DATS inhibited tumor growth in mice. In conclusion, we have determined that the l ‐cysteine/CSE/H2S pathway is involved in melanoma progression. 相似文献
65.
Balasubramanian Chandramouli Danilo Di Maio Giordano Mancini Vincenzo Barone Giuseppe Brancato 《PloS one》2015,10(3)
The mechanosensitive channel of large conductance (MscL) is a protein that responds to membrane tension by opening a transient pore during osmotic downshock. Due to its large pore size and functional reconstitution into lipid membranes, MscL has been proposed as a promising artificial nanovalve suitable for biotechnological applications. For example, site-specific mutations and tailored chemical modifications have shown how MscL channel gating can be triggered in the absence of tension by introducing charged residues at the hydrophobic pore level. Recently, engineered MscL proteins responsive to stimuli like pH or light have been reported. Inspired by experiments, we present a thorough computational study aiming at describing, with atomistic detail, the artificial gating mechanism and the molecular transport properties of a light-actuated bacterial MscL channel, in which a charge-induced gating mechanism has been enabled through the selective cleavage of photo-sensitive alkylating agents. Properties such as structural transitions, pore dimension, ion flux and selectivity have been carefully analyzed. Besides, the effects of charge on alternative sites of the channel with respect to those already reported have been addressed. Overall, our results provide useful molecular insights into the structural events accompanying the engineered MscL channel gating and the interplay of electrostatic effects, channel opening and permeation properties. In addition, we describe how the experimentally observed ionic current in a single-subunit charged MscL mutant is obtained through a hydrophobicity breaking mechanism involving an asymmetric inter-subunit motion. 相似文献
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Acceleration of cyanobacterial dominance in north temperate‐subarctic lakes during the Anthropocene 下载免费PDF全文
Zofia E. Taranu Irene Gregory‐Eaves Peter R. Leavitt Lynda Bunting Teresa Buchaca Jordi Catalan Isabelle Domaizon Piero Guilizzoni Andrea Lami Suzanne McGowan Heather Moorhouse Giuseppe Morabito Frances R. Pick Mark A. Stevenson Patrick L. Thompson Rolf D. Vinebrooke 《Ecology letters》2015,18(4):375-384
Increases in atmospheric temperature and nutrients from land are thought to be promoting the expansion of harmful cyanobacteria in lakes worldwide, yet to date there has been no quantitative synthesis of long‐term trends. To test whether cyanobacteria have increased in abundance over the past ~ 200 years and evaluate the relative influence of potential causal mechanisms, we synthesised 108 highly resolved sedimentary time series and 18 decadal‐scale monitoring records from north temperate‐subarctic lakes. We demonstrate that: (1) cyanobacteria have increased significantly since c. 1800 ce , (2) they have increased disproportionately relative to other phytoplankton, and (3) cyanobacteria increased more rapidly post c. 1945 ce . Variation among lakes in the rates of increase was explained best by nutrient concentration (phosphorus and nitrogen), and temperature was of secondary importance. Although cyanobacterial biomass has declined in some managed lakes with reduced nutrient influx, the larger spatio‐temporal scale of sedimentary records show continued increases in cyanobacteria throughout the north temperate‐subarctic regions. 相似文献
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Mona-Rita Yacoub Matteo Trimarchi George Cremona Sara Dal Farra Giuseppe Alvise Ramirez Valentina Canti Emanuel Della Torre Mattia Baldini Patrizia Pignatti Mario Bussi Maria Grazia Sabbadini Angelo A Manfredi Giselda Colombo 《Clinical and molecular allergy : CMA》2015,13(1)