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51.
The extent of whole‐genome copy number alterations predicts aggressive features in primary melanomas
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Greta Gandolfi Caterina Longo Elvira Moscarella Iris Zalaudek Valentina Sancisi Margherita Raucci Gloria Manzotti Mila Gugnoni Simonetta Piana Giuseppe Argenziano Alessia Ciarrocchi 《Pigment cell & melanoma research》2016,29(2):163-175
Recent evidence indicates that melanoma comprises distinct types of tumors and suggests that specific morphological features may help predict its clinical behavior. Using a SNP‐array approach, we quantified chromosomal copy number alterations (CNA) across the whole genome in 41 primary melanomas and found a high degree of heterogeneity in their genomic asset. Association analysis correlating the number and relative length of CNA with clinical, morphological, and dermoscopic attributes of melanoma revealed that features of aggressiveness were strongly linked to the overall amount of genomic damage. Furthermore, we observed that melanoma progression and survival were mainly affected by a low number of large chromosome losses and a high number of small gains. We identified the alterations most frequently associated with aggressive melanoma, and by integrating our data with publicly available gene expression profiles, we identified five genes which expression was found to be necessary for melanoma cells proliferation. In conclusion, this work provides new evidence that the phenotypic heterogeneity of melanoma reflects a parallel genetic diversity and lays the basis to define novel strategies for a more precise prognostic stratification of patients. 相似文献
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53.
Marina Padroni Andrea Bernardoni Carmine Tamborino Gloria Roversi Massimo Borrelli Andrea Saletti Alessandro De Vito Cristiano Azzini Luca Borgatti Onofrio Marcello Christopher d’Esterre Stefano Ceruti Ilaria Casetta Ting-Yim Lee Enrico Fainardi 《PloS one》2016,11(1)
Introduction
The capability of CT perfusion (CTP) Alberta Stroke Program Early CT Score (ASPECTS) to predict outcome and identify ischemia severity in acute ischemic stroke (AIS) patients is still questioned.Methods
62 patients with AIS were imaged within 8 hours of symptom onset by non-contrast CT, CT angiography and CTP scans at admission and 24 hours. CTP ASPECTS was calculated on the affected hemisphere using cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) maps by subtracting 1 point for any abnormalities visually detected or measured within multiple cortical circular regions of interest according to previously established thresholds. MTT-CBV ASPECTS was considered as CTP ASPECTS mismatch. Hemorrhagic transformation (HT), recanalization status and reperfusion grade at 24 hours, final infarct volume at 7 days and modified Rankin scale (mRS) at 3 months after onset were recorded.Results
Semi-quantitative and quantitative CTP ASPECTS were highly correlated (p<0.00001). CBF, CBV and MTT ASPECTS were higher in patients with no HT and mRS≤2 and inversely associated with final infarct volume and mRS (p values: from p<0.05 to p<0.00001). CTP ASPECTS mismatch was slightly associated with radiological and clinical outcomes (p values: from p<0.05 to p<0.02) only if evaluated quantitatively. A CBV ASPECTS of 9 was the optimal semi-quantitative value for predicting outcome.Conclusions
Our findings suggest that visual inspection of CTP ASPECTS recognizes infarct and ischemic absolute values. Semi-quantitative CBV ASPECTS, but not CTP ASPECTS mismatch, represents a strong prognostic indicator, implying that core extent is the main determinant of outcome, irrespective of penumbra size. 相似文献54.
Roberto De Giorgio Maurizio Mazzoni Claudia Vallorani Rocco Latorre Cristiano Bombardi Maria Laura Bacci Monica Forni Mirella Falconi Catia Sternini Paolo Clavenzani 《PloS one》2016,11(2)
BackgroundThe expression of taste receptors (TASRs) and their signalling molecules in the gastrointestinal (GI) epithelial cells, including enteroendocrine cells (EECs), suggests they participate in chemosensing mechanisms influencing GI physiology via the release of endocrine messengers. TASRs mediate gustatory signalling by interacting with different transducers, including α-gustducin (Gαgust) and α-transducin (Gαtran) G protein subunits. This study tested whether Gαtran and Gαgust immunoreactive (-IR) cells are affected by a short-term (3 days) and long-term (30 days) high protein (Hp) diet in the pig GI tract.ResultIn the stomach, Gαgust and Gαtran-IR cells contained serotonin (5-HT) and ghrelin (GHR), while in the small and large intestine, Gαgust and Gαtran-IR colocalized with 5-HT-, cholecystokinin (CCK)- and peptide YY (PYY)-IR. There was a significant increase in the density of Gαtran-IR cells in the pyloric mucosa in both short- and long-term Hp diet groups (Hp3 and Hp30) vs. the control group (Ctr) (P<0.05), while the increase of Gαgust-IR cells in the pyloric mucosa was significant in Hp30 group vs. Ctr and vs. Hp3 (P<0.05); these cells included Gαtran / 5HT-IR and Gαtran / GHR-IR cells (P<0.05 and P<0.001 vs. Ctr, respectively) as well as Gαgust /5-HT-IR or Gαgust / GHR-IR cells (P<0.05 and P<0.01 vs. Ctr, respectively). In the small intestine, we recorded a significant increase in Gαtran-IR cells in the duodenal crypts and a significant increase of Gαgust-IR cells in the jejunal crypts in Hp3 group compared to HP30 (P<0.05). With regard to the number of Gαtran-Gαgust IR cells colocalized with CCK or 5-HT, there was only a significant increase of Gαtran / CCK-IR cells in Hp3 group compared to Ctr (P = 0.01).ConclusionThis study showed an upregulation of selected subpopulations of Gαgust / Gαtran-IR cells in distinct regions of the pig GI tract by short- and long-term Hp diet lending support to TASR-mediated effects in metabolic homeostasis and satiety mechanisms. 相似文献
55.
Genetic and paleomodelling evidence of the population expansion of the cattle egret Bubulcus ibis in Africa during the climatic oscillations of the Late Pleistocene
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Carlos Congrains Antônio F. Carvalho Elder A. Miranda Graeme S. Cumming Dominic A. W. Henry Shiiwua A. Manu Jacinta Abalaka Cristiano D. Rocha Moussa S. Diop Joãozinho Sá Hamilton Monteiro Lars H. Holbech Francis Gbogbo Silvia N. Del Lama 《Journal of avian biology》2016,47(6):846-857
Increasing aridity during glacial periods produced the retraction of forests and the expansion of arid and semi‐arid environments in Africa, with consequences for birds. Cattle egret Bubulcus ibis is a dispersive species that prefers semi‐arid environments and requires proximity to bodies of water. We expected that climatic oscillations led to the expansion of the range of the cattle egret during arid periods, such as the Last Maximum Glacial (LGM) and contraction of distribution during the Last Interglacial (LIG) period, resulting in contact of populations previously isolated. We investigated this hypothesis by evaluating the genetic structure and population history of 15 cattle egret breeding colonies located in west and South Africa using the mitochondrial DNA (mtDNA) control region, mtDNA ATPase 8 and 6, and an intron of nuclear gene transforming growth factor‐beta 2. Occurrence data and bioclimatic information were used to generate ecological niche models of three periods (present, LGM and LIG). We used the genetic and paleomodelling data to assess the responses of the cattle egret from Africa to the climatic oscillations during the late Pleistocene. Genetic data revealed low levels of genetic differentiation, signs of isolation‐by‐distance, as well as recent increases in effective population size that started during the LGM. The observed low genetic structure may be explained by recent colonization events due to the demographic expansion following the last glacial period and by dispersal capacity of this species. The paleomodels corroborated the expansion during the LGM, and a more restricted potential distribution during the LIG. Our findinds supports the hypothesis that the species range of the cattle egret expanded during arid periods and contracted during wet periods. 相似文献
56.
Andrade Neto N. F. Longo E. Matsui K. N. Paskocimas C. A. Bomio M. R. D. Motta F. V. 《Plasmonics (Norwell, Mass.)》2019,14(1):79-89
Plasmonics - AgCl/CuO heterostructures were synthesized via a sonochemical method. AgCl/CuO molar compositions of 1:1 and 2:1 were prepared, respectively. Such compositions were prepared using... 相似文献
57.
58.
Leite ES Santana SR Hünenberger PH Freitas LC Longo RL 《Journal of molecular modeling》2007,13(9):1017-1025
The relative stabilities of the alkali [M ⊂ 222]+ cryptates (M = Na, K, Rb and Cs) in the gas phase and in solution (80:20 v/v methanol:water mixture) at 298 K, are computed
using a combination of ab initio quantum-chemical calculations (HF/6-31G and MP2/6-31+G*//HF/6-31+G*) and explicit-solvent
Monte Carlo free-energy simulations. The results suggest that the relative stabilities of the cryptates in solution are due
to a combination of steric effects (compression of large ions within the cryptand cavity), electronic effects (delocalization
of the ionic charge onto the cryptand atoms) and solvent effects (dominantly the ionic dessolvation penalty). Thus, the relative
stabilities in solution cannot be rationalized solely on the basis of a simple match or mismatch between the ionic radius
and the cryptand cavity size as has been suggested previously. For example, although the [K ⊂ 222]+ cryptate is found to be the most stable in solution, in agreement with experimental data, it is the [Na ⊂ 222]+ cryptate that is the most stable in the gas phase. The present results provide further support to the notion that the solvent
in which supramolecules are dissolved plays a key role in modulating molecular recognition processes.
Figure Alkali cryptates [M ⊂ 222]+ (M = Na, K, Rb and Cs) relative stabilities in gas and methanol:water solution: solvent effects
and molecular recognition
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
59.
Munton RP Tweedie-Cullen R Livingstone-Zatchej M Weinandy F Waidelich M Longo D Gehrig P Potthast F Rutishauser D Gerrits B Panse C Schlapbach R Mansuy IM 《Molecular & cellular proteomics : MCP》2007,6(2):283-293
Activity-dependent protein phosphorylation is a highly dynamic yet tightly regulated process essential for cellular signaling. Although recognized as critical for neuronal functions, the extent and stoichiometry of phosphorylation in brain cells remain undetermined. In this study, we resolved activity-dependent changes in phosphorylation stoichiometry at specific sites in distinct subcellular compartments of brain cells. Following highly sensitive phosphopeptide enrichment using immobilized metal affinity chromatography and mass spectrometry, we isolated and identified 974 unique phosphorylation sites on 499 proteins, many of which are novel. To further explore the significance of specific phosphorylation sites, we used isobaric peptide labels and determined the absolute quantity of both phosphorylated and non-phosphorylated peptides of candidate phosphoproteins and estimated phosphorylation stoichiometry. The analyses of phosphorylation dynamics using differentially stimulated synaptic terminal preparations revealed activity-dependent changes in phosphorylation stoichiometry of target proteins. Using this method, we were able to differentiate between distinct isoforms of Ca2+/calmodulin-dependent protein kinase (CaMKII) and identify a novel activity-regulated phosphorylation site on the glutamate receptor subunit GluR1. Together these data illustrate that mass spectrometry-based methods can be used to determine activity-dependent changes in phosphorylation stoichiometry on candidate phosphopeptides following large scale phosphoproteome analysis of brain tissue. 相似文献
60.
EcoHealth - A persistent 2-month long outbreak of Ranavirus in a natural community of amphibians contributed to a mass die-off of gopher frog tadpoles (Lithobates capito) and severe disease in... 相似文献