Search results for " Island"

The CpG island methylator phenotype in breast cancer is associated with the lobular subtype

2014

Background: Aberrations in DNA methylation patterns are well-described in human malignancies. However, the existence of the ‘CpG island methylator phenotype’ (CIMP) in human breast cancer is still controversial. Materials & methods: Illumina's HumanMethylation 450K BeadChip was used to analyze genome-wide DNA methylation patterns. Chromosomal abnormalities were determined by array-based CGH. Results: Invasive lobular breast carcinomas exhibit the highest number of differentially methylated CpG sites and a strong inverse correlation of aberrant DNA hypermethylation and copy number alterations. Nine differentially methylated regions within seven genes discriminating the investigated subg…

The genetic structure of Drosophila subobscura populations from the islands of Majorca and Minorca (Balearic Islands, Spain) based on allozymes and m…

1999

The genetic structure of seven populations of Drosophila subobscura from different locations on Majorca and Minorca (Balearic Islands, Spain) was studied using two types of markers: allozyme and mitochondrial DNA restriction analyses. Both markers showed congruent results. In the allozyme data, when the Acph-1 locus was excluded from the joint FST statistics, only three out of 21 comparisons were statistically significant, lending support to the hypothesis of low genetic differentiation. The mtDNA restriction analyses showed two haplotypes at a high frequency (more than 40% each), irrespective of the location considered, and a number of endemic haplotypes at very low frequencies (not higher…

Methyl-CpG-binding proteins

2000

CpG methylation, the most common epigenetic modification of vertebrate genomes, is primarily associated with transcriptional repression. MeCP2, MBD1, MBD2, MBD3 and MBD4 constitute a family of vertebrate proteins that share the methyl-CpG-binding domain (MBD). The MBD, consisting of about 70 residues, possesses a unique alpha/beta-sandwich structure with characteristic loops, and is able to bind single methylated CpG pairs as a monomer. All MBDs except MBD4, an endonuclease that forms a complex with the DNA mismatch-repair protein MLH1, form complexes with histone deacetylase. It has been established that MeCP2, MBD1 and MBD2 are involved in histone deacetylase-dependent repression and it i…

The rise and the fall of a Pseudomonas aeruginosa epidemic lineage in a hospital

2020

AbstractThe biological features that allow a pathogen to survive in the hospital environment are mostly unknown. The extinction of bacterial epidemics in hospitals is mostly attributed to changes in medical practice, including infection control, but the role of bacterial adaptation has never been documented. We analyzed a collection of Pseudomonas aeruginosa isolates belonging to the Besançon Epidemic Strain (BES), responsible for a 12-year nosocomial outbreak, using a genotype-to-phenotype approach. Bayesian analysis estimated the emergence of the clone in the hospital five years before its opening, during the creation of its water distribution network made of copper. BES survived better t…

Patterns of genomic instability in gastric cancer: clinical implications and perspectives

2007

In gastric cancer (GC) the loss of genomic stability represents a key molecular step that occurs early in the carcinogenesis process and creates a permissive environment for the accumulation of genetic and epigenetic alterations in tumor suppressor genes and oncogenes. It is widely accepted that GC can follow at least two major genomic instability pathways, microsatellite instability (MSI) and chromosome instability (CIN). MSI is responsible for a well-defined subset of GCs. CIN represents a more common pathway comprising heterogeneous subsets of GC. In addition to MSI and CIN, the CpG islands methylator phenotype (CIMP) plays an important role in gastric carcinogenesis. CIMP may lead to th…

Legionella pneumophila pangenome reveals strain-specific virulence factors

2010

Abstract Background Legionella pneumophila subsp. pneumophila is a gram-negative γ-Proteobacterium and the causative agent of Legionnaires' disease, a form of epidemic pneumonia. It has a water-related life cycle. In industrialized cities L. pneumophila is commonly encountered in refrigeration towers and water pipes. Infection is always via infected aerosols to humans. Although many efforts have been made to eradicate Legionella from buildings, it still contaminates the water systems. The town of Alcoy (Valencian Region, Spain) has had recurrent outbreaks since 1999. The strain "Alcoy 2300/99" is a particularly persistent and recurrent strain that was isolated during one of the most signifi…

A LA-ICP-MS STUDY OF CARBONATITES FROM FUERTEVENTURA, CANARY ISLAND

Carbonatites complexes are very rare in oceanic environments and in the Atlantic Ocean they can be only found at Cape Verde islands and Fuerteventura. Fuerteventura is the second largest island in the Canary Archipelago and is located on a transitional, continental to oceanic, crust. It consists essentially of Mesozoic sediments, submarine volcanic rocks, subaerial basaltic and trachytic series, ultramafic, mafic to felsic intrusives (clinopyroxenites, melteijites-ijolites, nepheline-monzogabbros, nepheline-sienites) and carbonatitic dike swarms (age 25 Ma). Carbonatite dike (Ca-carbonatites) mineralogy consists of calcite, aegirine-augite, albite, K-feldspar, biotite, apatite, Fe-Ti oxides…

Ecotoxicity assessment of natural attenuation effects at a historical dumping site in the western Baltic Sea.

2005

During the late 1950s and early 1960s of the past century, industrial waste material highly enriched in various contaminants (heavy metals, PAHs) was dumped in the inner Mecklenburg Bay, western Baltic Sea. Large-scale shifts in the spatial distribution of heavy metals in surface sediments were mapped by geochemical monitoring in the mid-1980s and 12 years later in 1997. A further study in 2001 was designed to investigate the small-scale spatial distribution of contaminants inside, on top of, and around the historical dumping ground and to examine possible effects to benthic organisms (Arctica islandica, microbiological toxicity tests). The site is located within an area characterized by a …

Concept of Biogenic Ferromanganese Crust Formation: Coccoliths as Bio-seeds in Crusts from Central Atlantic Ocean (Senghor Seamount/Cape Verde)

2011

At depths of 2,000 to 3,000 m, seamounts from the Cape Verde archipelago (Central Atlantic Ocean) are largely covered with ferromanganese crusts. Here we studied 60 to 150 mm thick crusts from the Senghor Seamount (depth: 2257.4 m). The crusts have a non lamellated texture and are covered with spherical nodules. The chemical composition shows a dominance of MnO2 (26.1%) and Fe2O3 (38.8%) with considerable amounts of Co (0.74%) and TiO2 (2.1%). Analysis by scanning electron probe microanalyzer (EPMA) revealed a well defined compositional zonation of micro-layers; the distribution pattern of Mn does not match that of Fe. Analysis by high resolution scanning electron microscopy (SEM) revealed…

Environmental Gamma Radiation Measurements on the Island of Pantelleria

1992

The population exposure to those living on the island of Pantelleria, Italy, was estimated by measuring the natural gamma background. Gamma spectra of natural rocks and measurements of absorbed dose in air were taken. A correlation was found between the mean gamma exposure rate and the mean values of natural radionuclide concentrations in the investigated rocks.