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971.
Chiara Rancan Leah Schirrmann Corinna Hüls Reinhard Zeidler Andreas Moosmann 《PLoS pathogens》2015,11(6)
The common pathogen Epstein-Barr virus (EBV) transforms normal human B cells and can cause cancer. Latent membrane protein 2A (LMP2A) of EBV supports activation and proliferation of infected B cells and is expressed in many types of EBV-associated cancer. It is not clear how latent EBV infection and cancer escape elimination by host immunity, and it is unknown whether LMP2A can influence the interaction of EBV-infected cells with the immune system. We infected primary B cells with EBV deleted for LMP2A, and established lymphoblastoid cell lines (LCLs). We found that CD8+ T cell clones showed higher reactivity against LMP2A-deficient LCLs compared to LCLs infected with complete EBV. We identified several potential mediators of this immunomodulatory effect. In the absence of LMP2A, expression of some EBV latent antigens was elevated, and cell surface expression of MHC class I was marginally increased. LMP2A-deficient LCLs produced lower amounts of IL-10, although this did not directly affect CD8+ T cell recognition. Deletion of LMP2A led to several changes in the cell surface immunophenotype of LCLs. Specifically, the agonistic NKG2D ligands MICA and ULBP4 were increased. Blocking experiments showed that NKG2D activation contributed to LCL recognition by CD8+ T cell clones. Our results demonstrate that LMP2A reduces the reactivity of CD8+ T cells against EBV-infected cells, and we identify several relevant mechanisms. 相似文献
972.
Neuroendocrine (Merkel-cell) carcinoma of the skin, a neoplasm usually found in elderly individuals, is often locally aggressive and has the potential to metastasize to lymph nodes and cause death. Microscopically the neoplasm is a small-cell carcinoma that involves primarily the dermis. We report a case of such a neoplasm in a 61-year-old female, stressing the possible contribution of fine needle aspiration cytology in the recognition of this neoplasm and its differentiation from other small-cell neoplasms that may involve the skin. 相似文献
973.
Andrea Franzetti Isabella Gandolfi Valentina Bertolini Chiara Raimondi Marco Piscitello Maddalena Papacchini Giuseppina Bestetti 《International biodeterioration & biodegradation》2011,65(7):1095-1099
Bacteria able to produce biological emulsifiers were isolated from different environments using different isolation media with the aim of discovering the widest diversity. The phylogenetic diversity of the isolates was evaluated by 16S rRNA gene analysis. Among 190 isolated strains, 127 released extracellular emulsifiers able to stabilize oil-water emulsions when grown on low-cost substrates. Among these, the 35 isolates that showed the highest emulsifier production on different substrates were found to belong to 16 different bacterial genera. Overall, this is the first systematic study of the diversity of bioemulsifier-producing bacteria and of their ability to produce bioemulsifiers on low-cost substrates. 相似文献
974.
975.
Laura Guidetti Cosme Franklim Buzzachera Gian Pietro Emerenziani Marco Meucci Francisco Saavedra Maria Chiara Gallotta Carlo Baldari 《PloS one》2015,10(4)
Speculation exists whether dance provides physiological stimuli adequate to promote health and fitness benefits. Unfortunately, research to date has not addressed the affective and exertional responses to dance. These responses are of interest as positive affective and exertional responses experienced during physical activity may play an important role in predicting adherence. The present study aims to examine the psychophysiological responses of different Salsa dance styles. Ten pairs of dancers performed two different structured lessons of Salsa dance, including Typical Salsa and Rueda de Casino lessons, and a non-structured Salsa dance at a night club. Physiological responses (i.e., percent of heart rate reserve; %HRR) were continuously assessed and perceived exertion and affective valence were rated every 15 min throughout the trials. %HRR responses differed between the Salsa dance styles (%HRR from 41.3 to 51.9%), and participants were dancing at intensities near their ventilatory threshold. Specifically, Typical Salsa lesson elicited lower %HRR responses than Rueda de Casino lesson (p < 0.05), but similar %HRR responses to Salsa dance at a night club condition (p > 0.05). Surprisingly, exertional (from 8 to 11) and affective (from +3 to +5) responses were unaffected by Salsa dance styles (p > 0.05). These data support that different Salsa dance styles provide physiological stimuli adequate to promote health and fitness benefits, and perhaps more importantly, produce pleasurable experiences, which in turn might lead to an increase in adherence to Salsa dancing which likely provides exercise-like health benefits. 相似文献
976.
Background
Various normalisation techniques have been developed in the context of microarray analysis to try to correct expression measurements for experimental bias and random fluctuations. Major techniques include: total intensity normalisation; intensity dependent normalisation; and variance stabilising normalisation. The aim of this paper is to discuss the impact of normalisation techniques for two-channel array technology on the process of identification of differentially expressed genes. 相似文献977.
INCREASE OF BRAIN TRYPTOPHAN BY ELECTROCONVULSIVE SHOCK IN RATS 总被引:1,自引:1,他引:0
A. Tagliamonte P. Tagliamonte G. Di Chiara R. Gessa G. L. Gessa 《Journal of neurochemistry》1972,19(6):1509-1512
—ECS markedly increased tryptophan and 5-hydroxyindoleacetic acid levels in brain. Brain serotonin and plasma tryptophan levels were unaffected. 相似文献
978.
Chiara Focaccetti Antonino Bruno Elena Magnani Desirée Bartolini Elisa Principi Katiuscia Dallaglio Eraldo O. Bucci Giovanna Finzi Fausto Sessa Douglas M. Noonan Adriana Albini 《PloS one》2015,10(2)
Antimetabolites are a class of effective anticancer drugs interfering in essential biochemical processes. 5-Fluorouracil (5-FU) and its prodrug Capecitabine are widely used in the treatment of several solid tumors (gastro-intestinal, gynecological, head and neck, breast carcinomas). Therapy with fluoropyrimidines is associated with a wide range of adverse effects, including diarrhea, dehydration, abdominal pain, nausea, stomatitis, and hand-foot syndrome. Among the 5-FU side effects, increasing attention is given to cardiovascular toxicities induced at different levels and intensities. Since the mechanisms related to 5-FU-induced cardiotoxicity are still unclear, we examined the effects of 5-FU on primary cell cultures of human cardiomyocytes and endothelial cells, which represent two key components of the cardiovascular system. We analyzed at the cellular and molecular level 5-FU effects on cell proliferation, cell cycle, survival and induction of apoptosis, in an experimental cardioncology approach. We observed autophagic features at the ultrastructural and molecular levels, in particular in 5-FU exposed cardiomyocytes. Reactive oxygen species (ROS) elevation characterized the endothelial response. These responses were prevented by a ROS scavenger. We found induction of a senescent phenotype on both cell types treated with 5-FU. In vivo, in a xenograft model of colon cancer, we showed that 5-FU treatment induced ultrastructural changes in the endothelium of various organs. Taken together, our data suggest that 5-FU can affect, both at the cellular and molecular levels, two key cell types of the cardiovascular system, potentially explaining some manifestations of 5-FU-induced cardiovascular toxicity. 相似文献
979.
Giulia Paciello Andrea Acquaviva Chiara Pighi Alberto Ferrarini Enrico Macii Alberto Zamo’ Elisa Ficarra 《PloS one》2015,10(3)
In this paper we present VDJSeq-Solver, a methodology and tool to identify clonal lymphocyte populations from paired-end RNA Sequencing reads derived from the sequencing of mRNA neoplastic cells. The tool detects the main clone that characterises the tissue of interest by recognizing the most abundant V(D)J rearrangement among the existing ones in the sample under study. The exact sequence of the clone identified is capable of accounting for the modifications introduced by the enzymatic processes. The proposed tool overcomes limitations of currently available lymphocyte rearrangements recognition methods, working on a single sequence at a time, that are not applicable to high-throughput sequencing data. In this work, VDJSeq-Solver has been applied to correctly detect the main clone and identify its sequence on five Mantle Cell Lymphoma samples; then the tool has been tested on twelve Diffuse Large B-Cell Lymphoma samples. In order to comply with the privacy, ethics and intellectual property policies of the University Hospital and the University of Verona, data is available upon request to ti.rvinu.oeneta@itnetu.otroppus after signing a mandatory Materials Transfer Agreement. VDJSeq-Solver JAVA/Perl/Bash software implementation is free and available at http://eda.polito.it/VDJSeq-Solver/. 相似文献
980.
Lesley Tilleman Stefania Abbruzzetti Chiara Ciaccio Giampiero De Sanctis Marco Nardini Alessandra Pesce Filip Desmet Luc Moens Sabine Van Doorslaer Stefano Bruno Martino Bolognesi Paolo Ascenzi Massimo Coletta Cristiano Viappiani Sylvia Dewilde 《PloS one》2015,10(6)
Studies of CO ligand binding revealed that two protein states with different ligand affinities exist in the protoglobin from Methanosarcina acetivorans (in MaPgb*, residue Cys(E20)101 was mutated to Ser). The switch between the two states occurs upon the ligation of MaPgb*. In this work, site-directed mutagenesis was used to explore the role of selected amino acids in ligand sensing and stabilization and in affecting the equilibrium between the “more reactive” and “less reactive” conformational states of MaPgb*. A combination of experimental data obtained from electronic and resonance Raman absorption spectra, CO ligand-binding kinetics, and X-ray crystallography was employed. Three amino acids were assigned a critical role: Trp(60)B9, Tyr(61)B10, and Phe(93)E11. Trp(60)B9 and Tyr(61)B10 are involved in ligand stabilization in the distal heme pocket; the strength of their interaction was reflected by the spectra of the CO-ligated MaPgb* and by the CO dissociation rate constants. In contrast, Phe(93)E11 is a key player in sensing the heme-bound ligand and promotes the rotation of the Trp(60)B9 side chain, thus favoring ligand stabilization. Although the structural bases of the fast CO binding rate constant of MaPgb* are still unclear, Trp(60)B9, Tyr(61)B10, and Phe(93)E11 play a role in regulating heme/ligand affinity. 相似文献