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51.
Sex chromosomes of basal placental mammals 总被引:1,自引:1,他引:0
Placental (eutherian) mammals are currently classified into four superordinal clades (Afrotheria, Xenarthra, Laurasiatheria and Supraprimates) of which one, the Afrotheria (a unique lineage of African origin), is generally considered to be basal. Therefore, Afrotheria provide a pivotal evolutionary link for studying fundamental differences between the sex chromosomes of human/mouse (both representatives of Supraprimates and the index species for studies of sex chromosomes) and those of the distantly related marsupials. In this study, we use female fibroblasts to investigate classical features of X chromosome inactivation including replication timing of the X chromosomes and Barr body formation. We also examine LINE-1 accumulation on the X chromosomes of representative afrotherians and look for evidence of a pseudoautosomal region (PAR). Our results demonstrate that asynchronous replication of the X chromosomes is common to Afrotheria, as with other mammals, and Barr body formation is observed across all Placentalia, suggesting that mechanisms controlling this evolved before their radiation. Finally, we provide evidence of a PAR (which marsupials lack) and demonstrate that LINE1 is accumulated on the afrotherian and xenarthran X, although this is probably not due to transposition events in a common ancestor, but rather ongoing selection to retain recently inserted LINE1 on the X. 相似文献
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Large-scale evaluation of candidate genes identifies associations between VEGF polymorphisms and bladder cancer risk 下载免费PDF全文
García-Closas M Malats N Real FX Yeager M Welch R Silverman D Kogevinas M Dosemeci M Figueroa J Chatterjee N Tardón A Serra C Carrato A García-Closas R Murta-Nascimento C Rothman N Chanock SJ 《PLoS genetics》2007,3(2):e29
Common genetic variation could alter the risk for developing bladder cancer. We conducted a large-scale evaluation of single nucleotide polymorphisms (SNPs) in candidate genes for cancer to identify common variants that influence bladder cancer risk. An Illumina GoldenGate assay was used to genotype 1,433 SNPs within or near 386 genes in 1,086 cases and 1,033 controls in Spain. The most significant finding was in the 5′ UTR of VEGF (rs25648, p for likelihood ratio test, 2 degrees of freedom = 1 × 10−5). To further investigate the region, we analyzed 29 additional SNPs in VEGF, selected to saturate the promoter and 5′ UTR and to tag common genetic variation in this gene. Three additional SNPs in the promoter region (rs833052, rs1109324, and rs1547651) were associated with increased risk for bladder cancer: odds ratio (95% confidence interval): 2.52 (1.06–5.97), 2.74 (1.26–5.98), and 3.02 (1.36–6.63), respectively; and a polymorphism in intron 2 (rs3024994) was associated with reduced risk: 0.65 (0.46–0.91). Two of the promoter SNPs and the intron 2 SNP showed linkage disequilibrium with rs25648. Haplotype analyses revealed three blocks of linkage disequilibrium with significant associations for two blocks including the promoter and 5′ UTR (global p = 0.02 and 0.009, respectively). These findings are biologically plausible since VEGF is critical in angiogenesis, which is important for tumor growth, its elevated expression in bladder tumors correlates with tumor progression, and specific 5′ UTR haplotypes have been shown to influence promoter activity. Associations between bladder cancer risk and other genes in this report were not robust based on false discovery rate calculations. In conclusion, this large-scale evaluation of candidate cancer genes has identified common genetic variants in the regulatory regions of VEGF that could be associated with bladder cancer risk. 相似文献
54.
Inés Segovia-Campos Agathe Martignier Montserrat Filella Jean-Michel Jaquet Daniel Ariztegui 《Environmental microbiology》2022,24(2):537-550
An unsuspected biomineralization process, which produces intracellular inclusions of amorphous calcium carbonate (ACC), was recently discovered in unicellular eukaryotes. These mineral inclusions, called micropearls, can be highly enriched with other alkaline-earth metals (AEM) such as Sr and Ba. Similar intracellular inclusions of ACC have also been observed in prokaryotic organisms. These comparable biomineralization processes involving phylogenetically distant microorganisms are not entirely understood yet. This review gives a broad vision of the topic in order to establish a basis for discussion on the possible molecular processes behind the formation of the inclusions, their physiological role, the impact of these microorganisms on the geochemical cycles of AEM and their evolutionary relationship. Finally, some insights are provided to guide future research. 相似文献
55.
Muix Alba Zlotnik Sergio Calvet Pere Espanol Montserrat Lodoso-Torrecilla Irene Ginebra Maria-Pau Dez Pedro Garca-Gonzlez Alberto 《Biomechanics and modeling in mechanobiology》2022,21(4):1099-1115
Biomechanics and Modeling in Mechanobiology - Scaffolds are microporous biocompatible structures that serve as material support for cells to proliferate, differentiate and form functional tissue.... 相似文献
56.
Feliciano Villar Montserrat Celdrán Rodrigo Serrat Josep Fabà Teresa Martínez 《Revista espa?ola de geriatría y gerontología》2019,54(1):12-18
Objectives
The study had three objectives: (a) To determine how staff perceives the frequency of different sexual expressions in long-term care facilities for older people; (2) to quantify policies aimed at guaranteeing residents’ sexual rights in such institutions, and (3) to determine factors influencing the presence of these kind of policies.Methods
A total of 160 Directors of Nursing and 623 technical staff from Spanish long term care residential facilities completed a self-administered questionnaire including ítems to assess the experience and estimated frequency of different sexual expressions, an inventory of policies regarding sexual expression, and the Spanish version of the Person-Centred Care Assessment Tool.Results
Certain sexual behaviours, such as kisses and hugs, or masturbation, are very frequent in nursing homes. Many participants have reported to staff members on having witnessed inappropriate sexual behaviours, such as exhibitionism (39%) or unwanted touching (27%). Policies in relation to guaranteeing residents’ sexual rights were the most frequently mentioned. In contrast, there were fewer participants who mentioned policies regarding training or availability of helpful materials and resources. Factors such as occupational level (Directors of Nursing vs.technical staff), personal education, the centre commitment to person-centred care, and estimated frequency of sexual behaviour were associated with a higher presence of sexual expression policies.Conclusion
Although sexual behaviours among residents are quite frequent, there is still room for improvement in policies that support residents’ expression of sexuality. Person-centred care models might help to guarantee sexual rights of older people living in long-term care facilities. 相似文献57.
Emma Roig-Molina Mirian Domenech María de Gracia Retamosa Montserrat Nácher-Vázquez Luis Rivas Beatriz Maestro Pedro García Ernesto García Jesús M. Sanz 《Biochimica et Biophysica Acta (BBA)/General Subjects》2019,1863(1):96-104
Antibiotic resistance is a global current threat of increasing importance. Moreover, biofilms represent a medical challenge since the inherent antibiotic resistance of their producers demands the use of high doses of antibiotics over prolonged periods. Frequently, these therapeutic measures fail, contributing to bacterial persistence, therefore demanding the development of novel antimicrobials. Esters of bicyclic amines (EBAs), which are strong inhibitors of Streptococcus pneumoniae growth, were initially designed as inhibitors of pneumococcal choline-binding proteins on the basis of their structural analogy to the choline residues in the cell wall. However, instead of mimicking the characteristic cell chaining phenotype caused by exogenously added choline on planktonic cultures of pneumococcal cells, EBAs showed an unexpected lytic activity. In this work we demonstrate that EBAs display a second, and even more important, function as cell membrane destabilizers. We then assayed the inhibitory and disintegrating activity of these molecules on pneumococcal biofilms. The selected compound (EBA 31) produced the highest effect on S. pneumoniae (encapsulated and non-encapsulated) biofilms at very low concentrations. EBA 31 was also effective on mixed biofilms of non-encapsulated S. pneumoniae plus non-typeable Haemophilus influenzae, two pathogens frequently forming a self-produced biofilm in the human nasopharynx. These results support the role of EBAs as a promising alternative for the development of novel, broad-range antimicrobial drugs encompassing both Gram-positive and Gram-negative pathogens. 相似文献
58.
Jordi Valls-Margarit Ivn Galvn-Femenía Daniel Matías-Snchez Natalia Blay Montserrat Puiggrs Anna Carreras Cecilia Salvoro Beatriz Corts Ramon Amela Xavier Farre Jon Lerga-Jaso Marta Puig Jose
Francisco Snchez-Herrero Victor Moreno Manuel Perucho Lauro Sumoy Lluís Armengol Olivier Delaneau Mario Cceres Rafael de
Cid David Torrents 《Nucleic acids research》2022,50(5):2464
The combined analysis of haplotype panels with phenotype clinical cohorts is a common approach to explore the genetic architecture of human diseases. However, genetic studies are mainly based on single nucleotide variants (SNVs) and small insertions and deletions (indels). Here, we contribute to fill this gap by generating a dense haplotype map focused on the identification, characterization, and phasing of structural variants (SVs). By integrating multiple variant identification methods and Logistic Regression Models (LRMs), we present a catalogue of 35 431 441 variants, including 89 178 SVs (≥50 bp), 30 325 064 SNVs and 5 017 199 indels, across 785 Illumina high coverage (30x) whole-genomes from the Iberian GCAT Cohort, containing a median of 3.52M SNVs, 606 336 indels and 6393 SVs per individual. The haplotype panel is able to impute up to 14 360 728 SNVs/indels and 23 179 SVs, showing a 2.7-fold increase for SVs compared with available genetic variation panels. The value of this panel for SVs analysis is shown through an imputed rare Alu element located in a new locus associated with Mononeuritis of lower limb, a rare neuromuscular disease. This study represents the first deep characterization of genetic variation within the Iberian population and the first operational haplotype panel to systematically include the SVs into genome-wide genetic studies. 相似文献
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60.
Epithelial cells have a distinctive polarity based on the restricted distribution of proteins and junctional complexes along an apical-basal axis. Studying the formation of the polarized ectoderm of the Drosophila embryo has identified a number of the molecules that establish this polarity. The Crumbs (Crb) complex is one of three separate complexes that cooperate to control epithelial polarity and the formation of zonula adherens. Here we show that glaikit (gkt), a member of the phospholipase D superfamily, is essential for the formation of epithelial polarity and for neuronal development during Drosophila embryogenesis. In epithelial cells, gkt acts to localize the Crb complex of proteins to the apical lateral membrane. Loss of gkt during neuronal development leads to a severe CNS architecture disruption that is not dependent on the Crb pathway but probably results from the disrupted localization of other membrane proteins. A mutation in the human homolog of gkt causes the neurodegenerative disease spinocerebellar ataxia with neuropathy (SCAN1), making it possible that a failure of membrane protein localization is a cause of this disease. 相似文献