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81.
Vaporidi K Vergadi E Kaniaris E Hatziapostolou M Lagoudaki E Georgopoulos D Zapol WM Bloch KD Iliopoulos D 《American journal of physiology. Lung cellular and molecular physiology》2012,303(3):L199-L207
The aim of this study was to investigate the changes induced by high tidal volume ventilation (HVTV) in pulmonary expression of micro-RNAs (miRNAs) and identify potential target genes and corresponding miRNA-gene networks. Using a real-time RT-PCR-based array in RNA samples from lungs of mice subjected to HVTV for 1 or 4 h and control mice, we identified 65 miRNAs whose expression changed more than twofold upon HVTV. An inflammatory and a TGF-β-signaling miRNA-gene network were identified by in silico pathway analysis being at highest statistical significance (P = 10(-43) and P = 10(-28), respectively). In the inflammatory network, IL-6 and SOCS-1, regulated by miRNAs let-7 and miR-155, respectively, appeared as central nodes. In TGF-β-signaling network, SMAD-4, regulated by miR-146, appeared as a central node. The contribution of miRNAs to the development of lung injury was evaluated in mice subjected to HVTV treated with a precursor or antagonist of miR-21, a miRNA highly upregulated by HVTV. Lung compliance was preserved only in mice treated with anti-miR-21 but not in mice treated with pre-miR-21 or negative-control miRNA. Both alveolar-arterial oxygen difference and protein levels in bronchoalveolar lavage were lower in mice treated with anti-miR-21 than in mice treated with pre-miR-21 or negative-control miRNA (D(A-a): 66 ± 27 vs. 131 ± 22, 144 ± 10 mmHg, respectively, P < 0.001; protein concentration: 1.1 ± 0.2 vs. 2.3 ± 1, 2.1 ± 0.4 mg/ml, respectively, P < 0.01). Our results show that HVTV induces changes in miRNA expression in mouse lungs. Modulation of miRNA expression can affect the development of HVTV-induced lung injury. 相似文献
82.
Chamakou AC Dede E Moutafi A Thanopoulos V Chryssanthopoulos S Loukopoulou S Pitsavos C Stefanadis C Davos CH 《Cytokine》2012,57(1):130-135
Introduction
Inflammation and neurohormonal activation are considered to be involved in the development of earlier and/or later complications in congenital heart disease patients, even after a successful repair of the lesion. It is not yet clarified what is the role of the therapeutic interventions in the occurrence of such a response and how it could be associated with possible postoperative complications.Aim
We sought to assess the inflammatory and neurohormonal response to transcatheter closure of secundum type atrial septal defects (ASD) over a six-month follow-up period. We also evaluated the association between the respective markers and catheterization data as well as echocardiographic measurements.Methods
Plasma concentrations of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), N-terminal-proatrial natriuretic peptide (NT-proANP) and N-terminal-probrain natriuretic peptide (NT-proBNP) were assessed and echocardiographic measurements were performed in twenty-eight patients with atrial septal defect prior to, and at the first, second and sixth months post transcatheter closure. Thirty-three age-matched healthy volunteers were also enrolled.Results
IL-6 plasma levels, although higher preoperatively, [physical logarithm (ln) IL-6: 3.37 ± 0.66 vs 2.92 ± 0.44 pg/ml, p = 0.015], reached control levels postoperatively, at the end of the third month, whereas TNF-α and IL-10 were not influenced by the procedure. NT-proANP levels were elevated preoperatively compared to the control group (ln NT-proANP 3.78 ± 0.572 vs 3.48 ± 0.30, p = 0.031), with a further significant increase during the 1st month (ln NT-proANP 3.78 ± 0.572 vs 4.2 ± 0.42, p = 0.006), following the pattern of the left atrial volume enlargement, and remained high even 6 months after the procedure .On the other hand, the initially normal concentrations of NT-proBNP, after a transient significant increase during the first month postoperatively (ln NT-proBNP 3.56 ± 0.94 vs 4.58 ± 0.91, p < 0.0001) returned to the controls’ levels at the end of the third month. Preoperative concentrations of NT-proANP positively correlated with NT-proBNP concentrations and pulmonary to systemic flow ratio (Qp/Qs).Conclusions
Transcatheter closure could improve, on a mid- term basis, the inflammatory process but natriuretic peptides’ secretion continues in parallel with left atrial volume increase. Further follow up is required to determine the long-term progress of the inflammatory and neurohormonal response to the procedure. 相似文献83.
Kentsis A Reed C Rice KL Sanda T Rodig SJ Tholouli E Christie A Valk PJ Delwel R Ngo V Kutok JL Dahlberg SE Moreau LA Byers RJ Christensen JG Woude GV Licht JD Kung AL Staudt LM Look AT 《Nature medicine》2012,18(7):1118-1122
Although the treatment of acute myeloid leukemia (AML) has improved substantially in the past three decades, more than half of all patients develop disease that is refractory to intensive chemotherapy. Functional genomics approaches offer a means to discover specific molecules mediating the aberrant growth and survival of cancer cells. Thus, using a loss-of-function RNA interference genomic screen, we identified the aberrant expression of hepatocyte growth factor (HGF) as a crucial element in AML pathogenesis. We found HGF expression leading to autocrine activation of its receptor tyrosine kinase, MET, in nearly half of the AML cell lines and clinical samples we studied. Genetic depletion of HGF or MET potently inhibited the growth and survival of HGF-expressing AML cells. However, leukemic cells treated with the specific MET kinase inhibitor crizotinib developed resistance resulting from compensatory upregulation of HGF expression, leading to the restoration of MET signaling. In cases of AML where MET is coactivated with other tyrosine kinases, such as fibroblast growth factor receptor 1 (FGFR1), concomitant inhibition of FGFR1 and MET blocked this compensatory HGF upregulation, resulting in sustained logarithmic cell killing both in vitro and in xenograft models in vivo. Our results show a widespread dependence of AML cells on autocrine activation of MET, as well as the key role of compensatory upregulation of HGF expression in maintaining leukemogenic signaling by this receptor. We anticipate that these findings will lead to the design of additional strategies to block adaptive cellular responses that drive compensatory ligand expression as an essential component of the targeted inhibition of oncogenic receptors in human cancers. 相似文献
84.
Andrew Fairbairn Eleni Asouti Julie Near Danièle Martinoli 《Vegetation History and Archaeobotany》2002,11(1-2):41-54
Analysis of charred plant macro-remains, including wood charcoals, cereals, seeds, tubers and fruits from the Neolithic site
of ?atalh?yük has indicated complex patterns of plant resource use and exploitation in the Konya plain during the early Holocene.
Evidence presented in this paper shows that settlement location was not dictated by proximity to high quality arable land
and direct access to arboreal resources (firewood, timber, fruit producing species). A summary of the patterns observed in
sample composition and species representation is outlined here together with preliminary interpretations of these results
within their broader regional context.
Received September 4, 2001 / Accepted April 9, 2002 相似文献
85.
Kim E. Haworth Ira Islam Matthew Breen Wendy Putt Eleni Makrinou Matthew Binns David Hopkinson Yvonne Edwards 《Mammalian genome》2001,12(8):622-629
We describe the construction of a dog embryonic head/neck cDNA library and the isolation of the dog homolog of the Treacher
Collins Syndrome gene, TCOF1. The protein shows a similar three-domain structure to that described for human TCOF1, but the dog gene lacks exon 10 and
contains two exons not present in the human sequence. In addition, exon 19 is differentially spliced in the dog. How these
structural differences relate to TCOF1 phosphorylation is discussed. Isolation of a genomic clone allowed the exon/intron
boundaries to be characterized and the dog TCOF1 gene to be mapped to CF Chr 4q31, a region syntenic to human Chr 5. Genetic analysis of DNA of dogs from 13 different breeds
identified nine DNA sequence variants, three of which gave rise to amino acid substitutions. Grouping dogs according to head
type showed that a C396T variant, leading to a Pro117Ser substitution, is associated with skull/face shape in our dog panel.
The numbers are small, but the association between the T allele and brachycephaly, broad skull/short face, was highly significant
(p= 0.000024). The short period of time during which the domestic dog breeds have been established suggests that this mutation
has arisen only once in the history of dog domestication.
Received: 12 January 2001 / Accepted: 1 April 2001 相似文献
86.
Eleni Karali Beat Brunner Ruth Doherty Anna M. Hersperger Mark D. A. Rounsevell 《Human ecology: an interdisciplinary journal》2013,41(6):915-926
Identifying and interpreting the heterogeneity of farmer behaviour is becoming increasingly important in support of policy- and decision-making goals. This paper explores whether observed differences in farming practices can be interpreted from the heterogeneity of farmer behaviour. Farmer attitudes and objectives were analysed using a combination of principal components and cluster analysis applied to responses to statements in a telephone-based survey. Respondents were classified into four profiles; business-oriented, lifestylers, multifunctionalists and traditionalists. Each profile differed in terms of farm management practices, the amount of land farmers either managed or owned, the existence of successors and the importance placed on household members in providing information. The results suggest that knowledge of farmer behavioural profiles could support more targeted policy development that accounts for alternative farmer goals. However, similarities were also found between the profiles, suggesting that farmer behaviour would be better interpreted as a dynamic set of identities, rather than as static profiles. 相似文献
87.
Eleni?Petsalaki Maria?Dandoulaki George?ZachosEmail authorView authors OrcID profile 《Chromosoma》2018,127(4):461-473
Formation of stable kinetochore-microtubule attachments is essential for accurate chromosome segregation in human cells and depends on the NDC80 complex. We recently showed that Chmp4c, an endosomal sorting complex required for transport protein involved in membrane remodelling, localises to prometaphase kinetochores and promotes cold-stable kinetochore microtubules, faithful chromosome alignment and segregation. In the present study, we show that Chmp4c associates with the NDC80 components Hec1 and Nuf2 and is required for optimal NDC80 stability and Hec1-Nuf2 localisation to kinetochores in prometaphase. However, Chmp4c-depletion does not cause a gross disassembly of outer or inner kinetochore complexes. Conversely, Nuf2 is required for Chmp4c kinetochore targeting. Constitutive Chmp4c kinetochore tethering partially rescues cold-stable microtubule polymers in cells depleted of the endogenous Nuf2, showing that Chmp4c also contributes to kinetochore-microtubule stability independently of regulating Hec1 and Nuf2 localisation. Chmp4c interacts with tubulin in cell extracts, and binds and bundles microtubules in vitro through its highly basic N-terminal region (amino acids 1–77). Furthermore, the N-terminal region of Chmp4c is required for cold-stable kinetochore microtubules and efficient chromosome alignment. We propose that Chmp4c promotes stable kinetochore-microtubule attachments by regulating Hec1–Nuf2 localisation to kinetochores in prometaphase and by binding to spindle microtubules. These results identify Chmp4c as a novel protein that regulates kinetochore-microtubule interactions to promote accurate chromosome segregation in human cells. 相似文献
88.
Zoumpopoulou Georgia Tzouvanou Alexandra Mavrogonatou Eleni Alexandraki Voula Georgalaki Marina Anastasiou Rania Papadelli Marina Manolopoulou Eugenia Kazou Maria Kletsas Dimitris Papadimitriou Konstantinos Tsakalidou Effie 《Probiotics and antimicrobial proteins》2018,10(2):313-322
Probiotics and Antimicrobial Proteins - The increased consumers’ interest on the positive role of food in wellbeing and health underscores the need to determine new probiotic microorganisms.... 相似文献
89.
Aromatic amino-acid side chains are essential components for the structure and function of proteins. We present herein a set of NMR experiments for time-efficient resonance assignment of histidine and tyrosine side chains in uniformly 13C/15N-labeled proteins. The use of band-selective 13C pulses allows to deal with linear chains of coupled spins, thus avoiding signal loss that occurs in branched spin systems during coherence transfer. Furthermore, our pulse schemes make use of longitudinal 1H relaxation enhancement, Ernst-angle excitation, and simultaneous detection of 1H and 13C steady-state polarization to achieve significant signal enhancements. 相似文献