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Cazzanelli Matteo Soria-Barreto Miriam Castillo María Mercedes Rodiles-Hernández Rocío 《Hydrobiologia》2021,848(4):773-797
Hydrobiologia - Floodplains are some of the most productive and diverse ecosystems on Earth. The Usumacinta River Basin, in the Southern Gulf of Mexico, hosts several floodplain lakes, whose... 相似文献
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Beatriz G. de la Torre Anna Maria Aviñó Mónica Escarceller Miriam Royo Fernando Albericio Ramon Eritja 《Nucleosides, nucleotides & nucleic acids》2013,32(9):993-1005
Abstract The preparation of a base-labile (Dnpe) protected derivative of 6-mercaptohexanol is described. The use of the phosphoramidite derivative of this compound improves both yields and the time needed for the preparation of oligonucleotides containing a thiol group at the 5′-end. 相似文献
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Miriam Ragle Aure Suvi-Katri Leivonen Thomas Fleischer Qian Zhu Jens Overgaard Jan Alsner Trine Tramm Riku Louhimo Grethe I Grenaker Aln?s Merja Per?l? Florence Busato Nizar Touleimat J?rg Tost Anne-Lise B?rresen-Dale Sampsa Hautaniemi Olga G Troyanskaya Ole Christian Lingj?rde Kristine Kleivi Sahlberg Vessela N Kristensen 《Genome biology》2013,14(11):R126
Background
The global effect of copy number and epigenetic alterations on miRNA expression in cancer is poorly understood. In the present study, we integrate genome-wide DNA methylation, copy number and miRNA expression and identify genetic mechanisms underlying miRNA dysregulation in breast cancer.Results
We identify 70 miRNAs whose expression was associated with alterations in copy number or methylation, or both. Among these, five miRNA families are represented. Interestingly, the members of these families are encoded on different chromosomes and are complementarily altered by gain or hypomethylation across the patients. In an independent breast cancer cohort of 123 patients, 41 of the 70 miRNAs were confirmed with respect to aberration pattern and association to expression. In vitro functional experiments were performed in breast cancer cell lines with miRNA mimics to evaluate the phenotype of the replicated miRNAs. let-7e-3p, which in tumors is found associated with hypermethylation, is shown to induce apoptosis and reduce cell viability, and low let-7e-3p expression is associated with poorer prognosis. The overexpression of three other miRNAs associated with copy number gain, miR-21-3p, miR-148b-3p and miR-151a-5p, increases proliferation of breast cancer cell lines. In addition, miR-151a-5p enhances the levels of phosphorylated AKT protein.Conclusions
Our data provide novel evidence of the mechanisms behind miRNA dysregulation in breast cancer. The study contributes to the understanding of how methylation and copy number alterations influence miRNA expression, emphasizing miRNA functionality through redundant encoding, and suggests novel miRNAs important in breast cancer. 相似文献59.
Alicia Barbero Susana Astiz Clemente J. Lopez-Bote Maria L. Perez-Solana Miriam Ayuso Isabel Garcia-Real Antonio Gonzalez-Bulnes 《PloS one》2013,8(10)
The present study aimed to determine, in a swine model of leptin resistance, the effects of type and timing of maternal malnutrition on growth patterns, adiposity and metabolic features of the progeny when exposed to an obesogenic diet during their juvenile development and possible concomitant effects of the offspring sex. Thus, four groups were considered. A CONTROL group involved pigs born from sows fed with a diet fulfilling their daily maintenance requirements for pregnancy. The treated groups involved the progeny of females fed with the same diet but fulfilling either 160% or 50% of pregnancy requirements during the entire gestation (OVERFED and UNDERFED, respectively) or 100% of requirements until Day 35 of pregnancy and 50% of such amount from Day 36 onwards (LATE-UNDERFED). OVERFED and UNDERFED offspring were more prone to higher corpulence and fat deposition from early postnatal stages, during breast-feeding; adiposity increased significantly when exposed to obesogenic diets, especially in females. The effects of sex were even more remarkable in LATE-UNDERFED offspring, which had similar corpulence to CONTROL piglets; however, females showed a clear predisposition to obesity. Furthermore, the three groups of pigs with maternal malnutrition showed evidences of metabolic syndrome and, in the case of individuals born from OVERFED sows, even of insulin resistance and the prodrome of type-2 diabetes. These findings support the main role of early nutritional programming in the current rise of obesity and associated diseases in ethnics with leptin resistance. 相似文献