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111.
Gorodkin J Cirera S Hedegaard J Gilchrist MJ Panitz F Jørgensen C Scheibye-Knudsen K Arvin T Lumholdt S Sawera M Green T Nielsen BJ Havgaard JH Rosenkilde C Wang J Li H Li R Liu B Hu S Dong W Li W Yu J Wang J Staefeldt HH Wernersson R Madsen LB Thomsen B Hornshøj H Bujie Z Wang X Wang X Bolund L Brunak S Yang H Bendixen C Fredholm M 《Genome biology》2007,8(4):R45-16
112.
Ágnes Baross Allen D Delaney H Irene Li Tarun Nayar Stephane Flibotte Hong Qian Susanna Y Chan Jennifer Asano Adrian Ally Manqiu Cao Patricia Birch Mabel Brown-John Nicole Fernandes Anne Go Giulia Kennedy Sylvie Langlois Patrice Eydoux JM Friedman Marco A Marra 《BMC bioinformatics》2007,8(1):1-18
Background
Genomic deletions and duplications are important in the pathogenesis of diseases, such as cancer and mental retardation, and have recently been shown to occur frequently in unaffected individuals as polymorphisms. Affymetrix GeneChip whole genome sampling analysis (WGSA) combined with 100 K single nucleotide polymorphism (SNP) genotyping arrays is one of several microarray-based approaches that are now being used to detect such structural genomic changes. The popularity of this technology and its associated open source data format have resulted in the development of an increasing number of software packages for the analysis of copy number changes using these SNP arrays.Results
We evaluated four publicly available software packages for high throughput copy number analysis using synthetic and empirical 100 K SNP array data sets, the latter obtained from 107 mental retardation (MR) patients and their unaffected parents and siblings. We evaluated the software with regards to overall suitability for high-throughput 100 K SNP array data analysis, as well as effectiveness of normalization, scaling with various reference sets and feature extraction, as well as true and false positive rates of genomic copy number variant (CNV) detection.Conclusion
We observed considerable variation among the numbers and types of candidate CNVs detected by different analysis approaches, and found that multiple programs were needed to find all real aberrations in our test set. The frequency of false positive deletions was substantial, but could be greatly reduced by using the SNP genotype information to confirm loss of heterozygosity. 相似文献113.
Svea Dittmann Annika Schmid Susanna Richter Konrad Trülzsch Jürgen Heesemann Gottfried Wilharm 《BMC microbiology》2007,7(1):67
Background
Pathogenic yersiniae (Y. pestis, Y. pseudotuberculosis, Y. enterocolitica) share a virulence plasmid encoding a type three secretion system (T3SS). This T3SS comprises more than 40 constituents. Among these are the transport substrates called Yops (Yersinia outer proteins), the specific Yop chaperones (Sycs), and the Ysc (Yop secretion) proteins which form the transport machinery. The effectors YopO and YopP are encoded on an operon together with SycO, the chaperone of YopO. The characterization of SycO is the focus of this study. 相似文献114.
Bonora GM Drioli S Ballico M Faccini A Corradini R Cogoi S Xodo L 《Nucleosides, nucleotides & nucleic acids》2007,26(6-7):661-664
The conjugation of a bioactive, fluorescent PNA sequence to high-molecular weight poly(ethylene glycol) (PEG) is described and the properties of the PEG-PNA conjugate are evaluated. 相似文献
115.
116.
Caretti A Morel S Milano G Fantacci M Bianciardi P Ronchi R Vassalli G von Segesser LK Samaja M 《Experimental biology and medicine (Maywood, N.J.)》2007,232(7):887-894
To study the in vivo dynamics of hypoxia-inducible factor 1alpha (HIF-1alpha), master regulator of O(2)-dependent gene expression, and mitogen-activated protein kinases (MAPKs) in the hypoxic myocardium, Sprague-Dawley rats (n = 4 to 6 per group) were exposed to 1-hr hypoxia (10% O(2)), 23-hr hypoxia, and 23-hr hypoxia, followed by reoxygenation. HIF-1alpha increased 15-fold after 1-hr hypoxia, remained constant for 23 hrs, and returned to baseline on reoxygenation. Extracellular signal-regulated kinases (ERK1/2) were unchanged throughout. Phosphorylated p38 increased 4-fold after 1-hr hypoxia and returned to baseline within 23-hr hypoxia. The activity of stress-activated protein kinases/c-Jun NH(2)-terminal kinases (JNKs), measured as phosphorylated c-Jun, increased 3-fold after 1-hr hypoxia and remained sustained afterward. Furthermore, HIF-1alpha was halved in rats that were administered with the p38 inhibitor SB202190 and made hypoxic for 1 hr. In conclusion, although very sensitive to the reoxygenation, HIF-1alpha is overexpressed in vivo in the hypoxic myocardium, and its acute induction by hypoxia is correlated with that of p38. 相似文献
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118.
Aurelio Reyes Laura Melchionda Alessia Nasca Franco Carrara Eleonora Lamantea Alice Zanolini Costanza Lamperti Mingyan Fang Jianguo Zhang Dario Ronchi Sara Bonato Gigliola Fagiolari Maurizio Moggio Daniele Ghezzi Massimo Zeviani 《American journal of human genetics》2015,97(1):186-193
Chronic progressive external ophthalmoplegia (CPEO) is common in mitochondrial disorders and is frequently associated with multiple mtDNA deletions. The onset is typically in adulthood, and affected subjects can also present with general muscle weakness. The underlying genetic defects comprise autosomal-dominant or recessive mutations in several nuclear genes, most of which play a role in mtDNA replication. Next-generation sequencing led to the identification of compound-heterozygous RNASEH1 mutations in two singleton subjects and a homozygous mutation in four siblings. RNASEH1, encoding ribonuclease H1 (RNase H1), is an endonuclease that is present in both the nucleus and mitochondria and digests the RNA component of RNA-DNA hybrids. Unlike mitochondria, the nucleus harbors a second ribonuclease (RNase H2). All affected individuals first presented with CPEO and exercise intolerance in their twenties, and these were followed by muscle weakness, dysphagia, and spino-cerebellar signs with impaired gait coordination, dysmetria, and dysarthria. Ragged-red and cytochrome c oxidase (COX)-negative fibers, together with impaired activity of various mitochondrial respiratory chain complexes, were observed in muscle biopsies of affected subjects. Western blot analysis showed the virtual absence of RNase H1 in total lysate from mutant fibroblasts. By an in vitro assay, we demonstrated that altered RNase H1 has a reduced capability to remove the RNA from RNA-DNA hybrids, confirming their pathogenic role. Given that an increasing amount of evidence indicates the presence of RNA primers during mtDNA replication, this result might also explain the accumulation of mtDNA deletions and underscores the importance of RNase H1 for mtDNA maintenance. 相似文献
119.
120.
Ants in their plants: Pseudomyrmex ants reduce primate,parrot and squirrel predation on Macrolobium acaciifolium (Fabaceae) seeds in Amazonian Brazil 下载免费PDF全文
Adrian A. Barnett Thais Almeida Richelly Andrade Sarah Boyle Marcelo Gonçalves de Lima Ann MacLarnon Caroline Ross Welma Sousa Silva Wilson R. Spironello Beatriz Ronchi‐Teles 《Biological journal of the Linnean Society. Linnean Society of London》2015,114(2):260-273
Although plant‐inhabiting ants are known to act as effective deterrents to a variety of vertebrate and invertebrate herbivores, this has been reported only once before for primates, a group better known for their predation of ants. In the present study, we investigated the effects that colonies of Pseudomyrmex viduus ants living in individual Macrolobium acaciifolium (Fabaceae) trees have on the rates of visitation and fruit removal by four taxa of seed‐predating vertebrates: the primate Cacajao melanocephalus ouakary; macaws (Ara spp.); large parrots (Amazona spp.); and the Northern Amazonian red squirrel (Sciurus igniventris). We found that ant presence significantly reduced both rates of visitation and of fruit removal by C. m. ouakary. The same pattern of reduced fruit removal was also observed for other seed predators (parrots, macaws, and squirrels) but not for visitation rates (although this may be a result of the small sample size). This appears to be only the second‐known demonstration of the repellent effect of ants on primates and, indeed, the first for squirrels and psittacine birds. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 114 , 260–273. 相似文献