Search results for "Gene Amplification"
showing 10 items of 100 documents
Gene amplification in fibroblasts from ataxia telangiectasia (AT) patients and in X-ray hypersensitive AT-like Chinese hamster mutants.
2001
In search of functions involved in the regulation of gene amplification, and given the relevance of chromosome breakage in initiating the process, we analyzed the gene amplification ability of cells hypersensitive to inducers of DNA double-strand breaks and defective in cell cycle control: two human fibroblast strains derived from patients affected by ataxia telangiectasia (AT) and two hamster mutant cell lines belonging to complementation group XRCC8 of the rodent X-ray-sensitive mutants. These mutants are considered hamster models of AT cells. To measure gene amplification, the frequency and the rate of occurrence of N-(phosphonacetyl)-L-aspartate resistant cells were determined. In both …
PCR for the detection of pathogens in neonatal early onset sepsis.
2020
Background A large proportion of neonates are treated for presumed bacterial sepsis with broad spectrum antibiotics even though their blood cultures subsequently show no growth. This study aimed to investigate PCR-based methods to identify pathogens not detected by conventional culture. Methods Whole blood samples of 208 neonates with suspected early onset sepsis were tested using a panel of multiplexed bacterial PCRs targeting Streptococcus pneumoniae, Streptococcus agalactiae (GBS), Staphylococcus aureus, Streptococcus pyogenes (GAS), Enterobacteriaceae, Enterococcus faecalis, Enterococcus faecium, Ureaplasma parvum, Ureaplasma urealyticum, Mycoplasma hominis and Mycoplasma genitalium, a …
APOBEC4 Enhances the Replication of HIV-1
2016
APOBEC4 (A4) is a member of the AID/APOBEC family of cytidine deaminases. In this study we found a high mRNA expression of A4 in human testis. In contrast, there were only low levels of A4 mRNA detectable in 293T, HeLa, Jurkat or A3.01 cells. Ectopic expression of A4 in HeLa cells resulted in mostly cytoplasmic localization of the protein. To test whether A4 has antiviral activity similar to that of proteins of the APOBEC3 (A3) subfamily, A4 was co-expressed in 293T cells with wild type HIV-1 and HIV-1 luciferase reporter viruses. We found that A4 did not inhibit the replication of HIV-1 but instead enhanced the production of HIV-1 in a dose-dependent manner and seemed to act on the viral L…
Evaluating diagnostic indicators of urogenital Schistosoma haematobium infection in young women: A cross sectional study in rural South Africa
2018
BackgroundUrine microscopy is the standard diagnostic method for urogenital S. haematobium infection. However, this may lead to under-diagnosis of urogenital schistosomiasis, as the disease may present itself with genital symptoms in the absence of ova in the urine. Currently there is no single reliable and affordable diagnostic method to diagnose the full spectrum of urogenital S. haematobium infection. In this study we explore the classic indicators in the diagnosis of urogenital S. haematobium infection, with focus on young women.MethodsIn a cross-sectional study of 1237 sexually active young women in rural South Africa, we assessed four diagnostic indicators of urogenital S. haematobium…
Diagnosis of flavobacteriosis by direct amplification of rRNA genes
2002
A broad-range bacterial PCR method with universal 16S rDNA targeting primers and bacterial cultivation was used to identify the putative pathogen in flavobacterial outbreaks. Restriction fragment length polymorphism (PCR-RFLP) analysis and sequencing of the partial 16S rDNA PCR products of 10 skin samples and 10 representative isolates derived from the same fish specimens revealed differences between direct molecular and cultivation-based analysis. Flavobacterium columnare-like sequences dominated in the direct molecular analysis in most cases, whereas most of the isolates belonged to a phylogenetically heterogeneous group of flavobacteria clustering with F. hibernum. F. columnare was isola…
Gene amplification in fibroblasts from ataxia telangiectasia (AT) patients and in X-ray hypersensitive AT-like Chinese hamster mutants
2001
In search of functions involved in the regulation of gene amplification, and given the relevance of chromosome breakage in initiating the process, we analyzed the gene amplification ability of cells hypersensitive to inducers of DNA double-strand breaks and defective in cell cycle control: two human fibroblast strains derived from patients affected by ataxia telangiectasia (AT) and two hamster mutant cell lines belonging to complementation group XRCC8 of the rodent X-ray-sensitive mutants. These mutants are considered hamster models of AT cells. To measure gene amplification, the frequency and the rate of occurrence of N-(phosphonacetyl)-l-aspartate resistant cells were determined. In both …
Chromatin modifiers and recombination factors promote a telomere fold-back structure, that is lost during replicative senescence.
2020
Telomeres have the ability to adopt a lariat conformation and hence, engage in long and short distance intra-chromosome interactions. Budding yeast telomeres were proposed to fold back into subtelomeric regions, but a robust assay to quantitatively characterize this structure has been lacking. Therefore, it is not well understood how the interactions between telomeres and non-telomeric regions are established and regulated. We employ a telomere chromosome conformation capture (Telo-3C) approach to directly analyze telomere folding and its maintenance in S. cerevisiae. We identify the histone modifiers Sir2, Sin3 and Set2 as critical regulators for telomere folding, which suggests that a dis…
A new set of DNA macrochips for the yeast Saccharomyces cerevisiae: features and uses
2004
The yeast Saccharomyces cerevisiae has been widely used for the implementation of DNA chip technologies. For this reason and due to the extensive use of this organism for basic and applied studies, yeast DNA chips are being used by many laboratories for expression or genomic analyses. While membrane arrays (macroarrays) offer several advantages, for many laboratories they are not affordable. Here we report that a cluster of four Spanish molecular-biology yeast laboratories, with relatively small budgets, have developed a complete set of probes for the genome of S. cerevisiae. These have been used to produce a new type of macroarray on a nylon surface. The macroarrays have been evaluated and…
The Status of EGFR Modulates the Effect of miRNA-200c on ZEB1 Expression and Cell Migration in Glioblastoma Cells
2020
Migration of glioblastoma cells into surrounding tissue is one of the main features that makes this tumor incurable. We evaluated whole-genome miRNA expression profiling associated with different EGFR amplification patterns in 30 cases of primary glioblastoma. From the 64 miRNAs that showed differential expression between tumors with a high level of EGFR amplification and tumors without EGFR amplification, 40% were related with cell migration, being miR-200c the most differentially expressed between these two groups. We investigated the effect of miR-200c on ZEB1 expression and cell migration in an in vitro transfection model with a miR-200c mimic, a miR-200c inhibitor and siRNA targeting E…
Loss of a novel tumor suppressor gene locus at chromosome 8p is associated with leukemic mantle cell lymphoma
2001
Abstract Patients with mantle cell lymphoma (MCL) may present with either nodal or leukemic disease. The molecular determinants underlying this different biologic behavior are not known. This study compared the pattern of genetic abnormalities in patients with nodal and leukemic phases of MCL using comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH) for specific gene loci. Although both leukemic and nodal MCL showed similar genomic patterns of losses (involving 6q, 11q22-q23, 13q14, and 17p13) and gains (affecting 3q and 8q), genomic loss of chromosome 8p occurred more frequently in patients with leukemic disease (79% versus 11%,P < .001). Subsequent…