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991.
María Asunción García-González David Nicolás-Pérez Angel Lanas Luis Bujanda Patricia Carrera Rafael Benito Mark Strunk Federico Sope?a Santos Santolaria Elena Piazuelo Pilar Jiménez Rafael Campo Jesús Espinel Marisa Manzano Fernando Geijo María Pellisé Ferrán González-Huix Jorge Espinós Manuel Zaballa Llúcia Titó Luis Barranco Roberto Pazo Enrique Quintero 《PloS one》2012,7(9)
Background
Genetic factors influencing the prognosis of gastric adenocarcinoma (GAC) are not well known. Given the relevance of cytokines and other pro-inflammatory mediators in cancer progression and invasiveness, we aimed to assess the prognostic role of several functional cytokine and cyclooxygenase gene polymorphisms in patients with GAC.Methodology
Genomic DNA from 380 Spanish Caucasian patients with primary GAC was genotyped for 23 polymorphisms in pro-inflammatory (IL1B, TNFA, LTA, IL6, IL12p40), anti-inflammatory (IL4, IL1RN, IL10, TGFB1) cytokine, and cyclooxygenase (PTGS1 and PTGS2) genes by PCR, RFLP and TaqMan assays. Clinical and histological information was collected prospectively. Survival curves were estimated by the Kaplan-Meier method and compared using the log rank test. Outcome was determined by analysis of Cox proportional hazards, adjusting for confounding factors.Results
The median follow-up period and median overall survival (OS) time were 9.9 months (range 0.4–120.3) and 10.9 months (95% CI: 8.9–14.1), respectively. Multivariate analysis identified tumor stages III (HR, 3.23; 95% CI:2–5.22) and IV (HR, 5.5; 95% CI: 3.51–8.63) as independent factors associated with a significantly reduced OS, whereas surgical treatment (HR: 0.44; 95%CI: 0.3–0.6) was related to a better prognosis of the disease. Concerning genetic factors, none of the 23 polymorphisms evaluated in the current study did influence survival. Moreover, no gene-environment interactions on GAC prognosis were observed.Conclusions
Our results show that, in our population, the panel of selected pro- and anti-inflammatory cytokine, and cyclooxygenase gene polymorphisms are not relevant in determining the prognosis of gastric adenocarcinoma. 相似文献992.
Human Ntera2/cl.D1 (NT2) cells treated with retinoic acid (RA) differentiate towards a well characterized neuronal phenotype sharing many features with human fetal neurons. In view of the emerging role of caspases in murine stem cell/neural precursor differentiation, caspases activity was evaluated during RA differentiation. Caspase-2, -3 and -9 activity was transiently and selectively increased in differentiating and non-apoptotic NT2-cells. SiRNA-mediated selective silencing of either caspase-2 (si-Casp2) or -9 (si-Casp9) was implemented in order to dissect the role of distinct caspases. The RA-induced expression of neuronal markers, i.e. neural cell adhesion molecule (NCAM), microtubule associated protein-2 (MAP2) and tyrosine hydroxylase (TH) mRNAs and proteins, was decreased in si-Casp9, but markedly increased in si-Casp2 cells. During RA-induced NT2 differentiation, the class III histone deacetylase Sirt1, a putative caspase substrate implicated in the regulation of the proneural bHLH MASH1 gene expression, was cleaved to a ~100 kDa fragment. Sirt1 cleavage was markedly reduced in si-Casp9 cells, even though caspase-3 was normally activated, but was not affected (still cleaved) in si-Casp2 cells, despite a marked reduction of caspase-3 activity. The expression of MASH1 mRNA was higher and occurred earlier in si-Casp2 cells, while was reduced at early time points during differentiation in si-Casp9 cells. Thus, caspase-2 and -9 may perform opposite functions during RA-induced NT2 neuronal differentiation. While caspase-9 activation is relevant for proper neuronal differentiation, likely through the fine tuning of Sirt1 function, caspase-2 activation appears to hinder the RA-induced neuronal differentiation of NT2 cells. 相似文献
993.
994.
Zonneveld Mv Scheldeman X Escribano P Viruel MA Van Damme P Garcia W Tapia C Romero J Sigueñas M Hormaza JI 《PloS one》2012,7(1):e29845
There is a growing call for inventories that evaluate geographic patterns in diversity of plant genetic resources maintained on farm and in species' natural populations in order to enhance their use and conservation. Such evaluations are relevant for useful tropical and subtropical tree species, as many of these species are still undomesticated, or in incipient stages of domestication and local populations can offer yet-unknown traits of high value to further domestication. For many outcrossing species, such as most trees, inbreeding depression can be an issue, and genetic diversity is important to sustain local production. Diversity is also crucial for species to adapt to environmental changes. This paper explores the possibilities of incorporating molecular marker data into Geographic Information Systems (GIS) to allow visualization and better understanding of spatial patterns of genetic diversity as a key input to optimize conservation and use of plant genetic resources, based on a case study of cherimoya (Annona cherimola Mill.), a Neotropical fruit tree species. We present spatial analyses to (1) improve the understanding of spatial distribution of genetic diversity of cherimoya natural stands and cultivated trees in Ecuador, Bolivia and Peru based on microsatellite molecular markers (SSRs); and (2) formulate optimal conservation strategies by revealing priority areas for in situ conservation, and identifying existing diversity gaps in ex situ collections. We found high levels of allelic richness, locally common alleles and expected heterozygosity in cherimoya's putative centre of origin, southern Ecuador and northern Peru, whereas levels of diversity in southern Peru and especially in Bolivia were significantly lower. The application of GIS on a large microsatellite dataset allows a more detailed prioritization of areas for in situ conservation and targeted collection across the Andean distribution range of cherimoya than previous studies could do, i.e. at province and department level in Ecuador and Peru, respectively. 相似文献
995.
996.
Garcia-Gomez A Ocio EM Crusoe E Santamaria C Hernández-Campo P Blanco JF Sanchez-Guijo FM Hernández-Iglesias T Briñón JG Fisac-Herrero RM Lee FY Pandiella A San Miguel JF Garayoa M 《PloS one》2012,7(4):e34914
Background
Bone loss, in malignant or non-malignant diseases, is caused by increased osteoclast resorption and/or reduced osteoblast bone formation, and is commonly associated with skeletal complications. Thus, there is a need to identify new agents capable of influencing bone remodeling. We aimed to further pre-clinically evaluate the effects of dasatinib (BMS-354825), a multitargeted tyrosine kinase inhibitor, on osteoblast and osteoclast differentiation and function.Methods
For studies on osteoblasts, primary human bone marrow mensenchymal stem cells (hMSCs) together with the hMSC-TERT and the MG-63 cell lines were employed. Osteoclasts were generated from peripheral blood mononuclear cells (PBMC) of healthy volunteers. Skeletally-immature CD1 mice were used in the in vivo model.Results
Dasatinib inhibited the platelet derived growth factor receptor-β (PDGFR-β), c-Src and c-Kit phosphorylation in hMSC-TERT and MG-63 cell lines, which was associated with decreased cell proliferation and activation of canonical Wnt signaling. Treatment of MSCs from healthy donors, but also from multiple myeloma patients with low doses of dasatinib (2–5 nM), promoted its osteogenic differentiation and matrix mineralization. The bone anabolic effect of dasatinib was also observed in vivo by targeting endogenous osteoprogenitors, as assessed by elevated serum levels of bone formation markers, and increased trabecular microarchitecture and number of osteoblast-like cells. By in vitro exposure of hemopoietic progenitors to a similar range of dasatinib concentrations (1–2 nM), novel biological sequelae relative to inhibition of osteoclast formation and resorptive function were identified, including F-actin ring disruption, reduced levels of c-Fos and of nuclear factor of activated T cells 1 (NFATc1) in the nucleus, together with lowered cathepsin K, αVβ3 integrin and CCR1 expression.Conclusions
Low dasatinib concentrations show convergent bone anabolic and reduced bone resorption effects, which suggests its potential use for the treatment of bone diseases such as osteoporosis, osteolytic bone metastasis and myeloma bone disease. 相似文献997.
Amparo M. Martínez Luis T. Gama Javier Ca?ón Catarina Ginja Juan V. Delgado Susana Dunner Vincenzo Landi Inmaculada Martín-Burriel M. Cecilia T. Penedo Clementina Rodellar Jose Luis Vega-Pla Atzel Acosta Luz A. álvarez Esperanza Camacho Oscar Cortés Jose R. Marques Roberto Martínez Ruben D. Martínez Lilia Melucci Guillermo Martínez-Velázquez Jaime E. Mu?oz Alicia Postiglioni Jorge Quiroz Philip Sponenberg Odalys Uffo Axel Villalobos Delsito Zambrano Pilar Zaragoza 《PloS one》2012,7(11)
Background
American Creole cattle presumably descend from animals imported from the Iberian Peninsula during the period of colonization and settlement, through different migration routes, and may have also suffered the influence of cattle directly imported from Africa. The introduction of European cattle, which began in the 18th century, and later of Zebu from India, has threatened the survival of Creole populations, some of which have nearly disappeared or were admixed with exotic breeds. Assessment of the genetic status of Creole cattle is essential for the establishment of conservation programs of these historical resources.Methodology/Principal Findings
We sampled 27 Creole populations, 39 Iberian, 9 European and 6 Zebu breeds. We used microsatellite markers to assess the origins of Creole cattle, and to investigate the influence of different breeds on their genetic make-up. The major ancestral contributions are from breeds of southern Spain and Portugal, in agreement with the historical ports of departure of ships sailing towards the Western Hemisphere. This Iberian contribution to Creoles may also include some African influence, given the influential role that African cattle have had in the development of Iberian breeds, but the possibility of a direct influence on Creoles of African cattle imported to America can not be discarded. In addition to the Iberian influence, the admixture with other European breeds was minor. The Creoles from tropical areas, especially those from the Caribbean, show clear signs of admixture with Zebu.Conclusions/Significance
Nearly five centuries since cattle were first brought to the Americas, Creoles still show a strong and predominant signature of their Iberian ancestors. Creole breeds differ widely from each other, both in genetic structure and influences from other breeds. Efforts are needed to avoid their extinction or further genetic erosion, which would compromise centuries of selective adaptation to a wide range of environmental conditions. 相似文献998.
Silvia Cesarini Cristina Bofill F.I. Javier Pastor Manfred T. Reetz Pilar Diaz 《Process Biochemistry》2012,47(12):2064-2071
Cold-adapted Pseudomonas aeruginosa LipC is a secreted lipase showing differential properties compared to its well-known counterpart LipA. LipC is fundamentally a cold-acting lipase, capable of tolerating high concentrations of ions and heavy metals, and showing a shift in substrate specificity when incubated at higher temperatures. These properties make LipC an interesting enzyme, well suited for biotechnological or environmental applications, where activity at low temperatures would be required. However, a relatively low thermal resistance constitutes the main drawback for using this enzyme in long-term operational processes. To overcome the lability of LipC, we developed a rational design system to modify specific sites on the enzyme structure to obtain an improved variant of the lipase bearing higher thermal stability, but without loss of its cold-adapted properties. Eight mutant libraries plus two point mutations were constructed affecting those amino acids showing the highest flexibility on the 3D model structure. After screening more than 3000 mutant clones, a LipC variant bearing two amino acid changes and the required thermostability and cold-adapted properties was obtained. The new variant D2_H8, with a 7-fold increased thermal stability in comparison to wild type LipC, will guarantee the use and maintenance of such a lipase in a number of processes being performed at low (4–20 °C) temperatures. 相似文献
999.
Cano-Soldado P Gorraitz E Errasti-Murugarren E Casado FJ Lostao MP Pastor-Anglada M 《American journal of physiology. Cell physiology》2012,302(1):C257-C266
SLC28 genes, encoding concentrative nucleoside transporter proteins (CNT), show little genetic variability, although a few single nucleotide polymorphisms (SNPs) have been associated with marked functional disturbances. In particular, human CNT1S546P had been reported to result in negligible thymidine uptake. In this study we have characterized the molecular mechanisms responsible for this apparent loss of function. The hCNT1S546P variant showed an appropriate endoplasmic reticulum export and insertion into the plasma membrane, whereas loss of nucleoside translocation ability affected all tested nucleoside and nucleoside-derived drugs. Site-directed mutagenesis analysis revealed that it is the lack of the serine residue itself responsible for the loss of hCNT1 function. This serine residue is highly conserved, and mutation of the analogous serine in hCNT2 (Ser541) and hCNT3 (Ser568) resulted in total and partial loss of function, respectively. Moreover, hCNT3, the only member that shows a 2Na(+)/1 nucleoside stoichiometry, showed altered Na(+) binding properties associated with a shift in the Hill coefficient, consistent with one Na(+) binding site being affected by the mutation. Two-electrode voltage-clamp studies using the hCNT1S546P mutant revealed the occurrence of Na(+) leak, which was dependent on the concentration of extracellular Na(+) indicating that, although the variant is unable to transport nucleosides, there is an uncoupled sodium transport. 相似文献
1000.
Alcaide P Martinelli R Newton G Williams MR Adam A Vincent PA Luscinskas FW 《American journal of physiology. Cell physiology》2012,303(4):C385-C395
Leukocyte transendothelial migration (TEM) is regulated by several signaling pathways including Src family kinases (SFK) and the small RhoGTPases. Previous studies have shown that vascular endothelial-cadherin (VE-cad) forms a complex with β-,γ-, and p120-catenins and this complex disassociates to form a transient gap during leukocyte TEM. Additionally, p120-catenin (p120-1A) overexpression in human umbilical vein endothelial cells (HUVEC) stabilizes VE-cad surface expression, prevents tyrosine phosphorylation of VE-cad, and inhibits leukocyte TEM. Based on reports showing that p120 overexpression in fibroblasts or epithelial cells inhibits RhoA and activates Rac and Cdc42 GTPases, and on other reports showing that RhoA activation in endothelial cells is necessary for leukocyte TEM, we reasoned that p120 overexpression inhibited TEM through inhibition of RhoA. To test this idea, we overexpressed a mutant p120 isoform, p120-4A, which does not interact with RhoA. p120-4A colocalized with VE-cad in HUVEC junctions and enhanced VE-cad surface expression, similar to overexpression of p120-1A. Interestingly, overexpression of either p120-4A or p120-1A dramatically blocked TEM, and overexpression of p120-1A in HUVEC did not affect RhoA basal activity or activation of RhoA and Rac induced by thrombin or ICAM-1 crosslinking. In contrast, biochemical studies revealed that overexpression of p120-1A reduced activated pY416-Src association with VE-cad. In summary, p120 overexpression inhibits neutrophil TEM independently of an effect on RhoA or Rac and instead blocks TEM by preventing VE-cad tyrosine phosphorylation and association of active Src with the VE-cad complex. 相似文献