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101.
102.
Enhanced Expression of Indoleamine 2,3‐Dioxygenase in Helicobacter pylori‐Infected Human Gastric Mucosa Modulates Th1/Th2 Pathway and Interleukin 17 Production 下载免费PDF全文
103.
Maria A. De Marco Stefano Porru Paolo Cordioli Bruno M. Cesana Ana Moreno Laura Calzoletti Lebana Bonfanti Arianna Boni Antonio Scotto Di Carlo Cecilia Arici Angela Carta Maria R. Castrucci Isabella Donatelli Paola Tomao Vittoria M. Peri Livia Di Trani Nicoletta Vonesch 《PloS one》2013,8(2)
Background
Pigs play a key epidemiologic role in the ecology of influenza A viruses (IAVs) emerging from animal hosts and transmitted to humans. Between 2008 and 2010, we investigated the health risk of occupational exposure to swine influenza viruses (SIVs) in Italy, during the emergence and spread of the 2009 H1N1 pandemic (H1N1pdm) virus.Methodology/Principal Findings
Serum samples from 123 swine workers (SWs) and 379 control subjects (Cs), not exposed to pig herds, were tested by haemagglutination inhibition (HI) assay against selected SIVs belonging to H1N1 (swH1N1), H1N2 (swH1N2) and H3N2 (swH3N2) subtypes circulating in the study area. Potential cross-reactivity between swine and human IAVs was evaluated by testing sera against recent, pandemic and seasonal, human influenza viruses (H1N1 and H3N2 antigenic subtypes). Samples tested against swH1N1 and H1N1pdm viruses were categorized into sera collected before (n. 84 SWs; n. 234 Cs) and after (n. 39 SWs; n. 145 Cs) the pandemic peak. HI-antibody titers ≥10 were considered positive. In both pre-pandemic and post-pandemic peak subperiods, SWs showed significantly higher swH1N1 seroprevalences when compared with Cs (52.4% vs. 4.7% and 59% vs. 9.7%, respectively). Comparable HI results were obtained against H1N1pdm antigen (58.3% vs. 7.7% and 59% vs. 31.7%, respectively). No differences were found between HI seroreactivity detected in SWs and Cs against swH1N2 (33.3% vs. 40.4%) and swH3N2 (51.2 vs. 55.4%) viruses. These findings indicate the occurrence of swH1N1 transmission from pigs to Italian SWs.Conclusion/Significance
A significant increase of H1N1pdm seroprevalences occurred in the post-pandemic peak subperiod in the Cs (p<0.001) whereas SWs showed no differences between the two subperiods, suggesting a possible occurrence of cross-protective immunity related to previous swH1N1 infections. These data underline the importance of risk assessment and occupational health surveillance activities aimed at early detection and control of SIVs with pandemic potential in humans. 相似文献104.
Rolfo A Many A Racano A Tal R Tagliaferro A Ietta F Wang J Post M Caniggia I 《PloS one》2010,5(10):e13288
Background
The pathogenesis of preeclampsia, a serious pregnancy disorder, is still elusive and its treatment empirical. Hypoxia Inducible Factor-1 (HIF-1) is crucial for placental development and early detection of aberrant regulatory mechanisms of HIF-1 could impact on the diagnosis and management of preeclampsia. HIF-1α stability is controlled by O2-sensing enzymes including prolyl hydroxylases (PHDs), Factor Inhibiting HIF (FIH), and E3 ligases Seven In Absentia Homologues (SIAHs). Here we investigated early- (E-PE) and late-onset (L-PE) human preeclamptic placentae and their ability to sense changes in oxygen tension occurring during normal placental development.Methods and Findings
Expression of PHD2, FIH and SIAHs were significantly down-regulated in E-PE compared to control and L-PE placentae, while HIF-1α levels were increased. PHD3 expression was increased due to decreased FIH levels as demonstrated by siRNA FIH knockdown experiments in trophoblastic JEG-3 cells. E-PE tissues had markedly diminished HIF-1α hydroxylation at proline residues 402 and 564 as assessed with monoclonal antibodies raised against hydroxylated HIF-1α P402 or P564, suggesting regulation by PHD2 and not PHD3. Culturing villous explants under varying oxygen tensions revealed that E-PE, but not L-PE, placentae were unable to regulate HIF-1α levels because PHD2, FIH and SIAHs did not sense a hypoxic environment.Conclusion
Disruption of oxygen sensing in E-PE vs. L-PE and control placentae is the first molecular evidence of the existence of two distinct preeclamptic diseases and the unique molecular O2-sensing signature of E-PE placentae may be of diagnostic value when assessing high risk pregnancies and their severity. 相似文献105.
Cell cycle regulation of NF-YC nuclear localization 总被引:3,自引:0,他引:3
NF-Y is a trimeric activator with histone fold, HFM, subunits that binds to the CCAAT-box and is required for a majority of cell cycle promoters, often in conjunction with E2Fs. In vivo binding of NF-Y is dynamic during the cell cycle and correlates with gene activation. We performed immunofluorescence studies on endogenous, GFP- and Flag-tagged overexpressed NF-Y subunits. NF-YA, NF-YB are nuclear proteins. Unexpectedly, NF-YC localizes both in cytoplamatic and nuclear compartments and its nuclear localization is determined by the interaction with its heterodimerization partner NF-YB. Most importantly, compartmentalization is regulated during the cell cycle of serum restimulated NIH3T3 cells, accumulating in the nucleus at the onset of S phase. These data point to the control of HFM heterodimerization as an important layer of NF-Y regulation during cell cycle progression. 相似文献
106.
Tetyana Denysenko Luisa Gennero Maria Augusta Roos Antonio Melcarne Carola Juenemann Giuliano Faccani Isabella Morra Giovanni Cavallo Stefano Reguzzi Gianpiero Pescarmona Antonio Ponzetto 《Cell biochemistry and function》2010,28(5):343-351
Glioblastoma Multiforme (GBM) is an incurable malignancy. GBM patients have a short life expectancy despite aggressive therapeutic approaches based on surgical resection followed by adjuvant radiotherapy and concomitant chemotherapy. Glioblastoma growth is characterized by a high motility of tumour cells, their resistance to both chemo/radio‐therapy, apoptosis inhibition leading to failure of conventional therapy. Cancer Stem Cells (CSCs), identified in GBM as well as in many other cancer types, express the membrane antigen prominin‐1 (namely CD133). These cells and normal Neural Stem Cells (NSC) share surface markers and properties, i.e. are able to self‐renew and differentiate into multiple cell types. Stem cell self‐renewal depends on microenvironmental cues, including Extracellular Matrix (ECM) composition and cell types. Therefore, the role of microenvironment needs to be evaluated to clarify its importance in tumour initiation and progression through CSCs. The specific microenvironment of CSCs was found to mimic in part the vascular niche of normal stem cells. The targeting of GMB CSCs may represent a powerful treatment approach. Lastly, in GBM patients cancer‐initiating cells contribute to the profound immune suppression that in turn correlated with CSCs STAT3 (CD133 + ). Further studies of microenvironment are needed to better understand the origin of GMB/GBM CSCs and its immunosuppressive properties. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
107.
Chiara Barbiero Isabella Lonciari Marcella Montico Lorenzo Monasta Roberta Penge Claudio Vio Patrizio Emanuele Tressoldi Valentina Ferluga Anna Bigoni Alessia Tullio Marco Carrozzi Luca Ronfani CENDi working group and for the Epidemiology of Dyslexia of Friuli Venezia Giulia working group 《PloS one》2012,7(10)
Background
Although dyslexia is one of the most common neurobehavioral disorders affecting children, prevalence is uncertain and available data are scanty and dated. The objective of this study is to evaluate the prevalence of dyslexia in an unselected school population using clearly defined and rigorous diagnostic criteria and methods.Methods
Cross sectional study. We selected a random cluster sample of 94 fourth grade elementary school classes of Friuli Venezia Giulia, a Region of North Eastern Italy. We carried out three consecutive levels of screening: the first two at school and the last at the Neuropsychiatry Unit of a third level Mother and Child Hospital. The main outcome measure was the prevalence of dyslexia, defined as the number of children positive to the third level of screening divided by the total number of children enrolled.Results
We recruited 1774 children aged 8–10 years, of which 1528 received parents’ consent to participate. After applying exclusion criteria, 1357 pupils constituted the final working sample. The prevalence of dyslexia in the enrolled population ranged from 3.1% (95% CI 2.2–4.1%) to 3.2% (95% CI 2.4–4.3%) depending on different criteria adopted. In two out of three children with dyslexia the disorder had not been previously diagnosed.Conclusions
This study shows that dyslexia is largely underestimated in Italy and underlines the need for reliable information on prevalence, in order to better allocate resources both to Health Services and Schools. 相似文献108.
109.
Identification of aminopyrimidine‐sulfonamides as potent modulators of Wag31‐mediated cell elongation in mycobacteria 下载免费PDF全文
János Pató Gaëlle S. Kolly Jana Korduláková Martin Forbak Joanna C. Evans Rita Székely Jan Rybniker Zuzana Palčeková Júlia Zemanová Isabella Santi François Signorino‐Gelo Liliana Rodrigues Anthony Vocat Adrian S. Covarrubias Monica G. Rengifo Kai Johnsson Sherry Mowbray Joseph Buechler Vincent Delorme Priscille Brodin Graham W. Knott José A. Aínsa Digby F. Warner Katarína Mikušová John D. McKinney Ruben C. Hartkoorn 《Molecular microbiology》2017,103(1):13-25
110.
Tatiana M. Vieira Isabella A. dos Santos Thayná S. Silva Carlos H. G. Martins Antônio E. M. Crotti 《化学与生物多样性》2018,15(8)
We evaluated the antimicrobial activity of 25 monoketone curcuminoids (MKCs) against a representative panel of cariogenic bacteria in terms of their minimum inhibitory concentration (MIC) values. Curcumin A ( 10 ) displayed promising activity against Streptococcus mutans (MIC = 50 μg/ml) and Streptococcus mitis (MIC = 50 μg/ml) as well as moderate activity against S. sanguinis (MIC = 100 μg/ml), Lactobacillus casei (MIC = 100 μg/ml), and Streptococcus salivarius (MIC = 200 μg/ml). Results indicated higher activity of compound 10 than that of its bis‐β‐diketone analog. Additionally, compounds 3a (1,5‐bis(4‐methylphenyl)pentan‐3‐one) and 7b (1,5‐bis(4‐bromophenyl)pentan‐3‐ol) were moderately active against S. mitis (MIC = 100 μg/ml) and S. salivarus (MIC = 200 μg/ml). 相似文献