Search results for "mismatch"

Interactions between DNA damage, repair, and transcription

2010

This review addresses a variety of mechanisms by which DNA repair interacts with transcription and vice versa. Blocking of transcriptional elongation is the best studied of these mechanisms. Transcription recovery after damage therefore has often been used as a surrogate marker of DNA repair in cells. However, it has become evident that relationships between DNA damage, repair, and transcription are more complex due to various indirect effects of DNA damage on gene transcription. These include inhibition of transcription by DNA repair intermediates as well as regulation of transcription and of the epigenetic status of the genes by DNA repair-related mechanisms. In addition, since transcript…

Hypoxia and Human Genome Stability: Downregulation of BRCA2 Expression in Breast Cancer Cell Lines

2013

Previously, it has been reported that hypoxia causes increased mutagenesis and alteration in DNA repair mechanisms. In 2005, an interesting study showed that hypoxia-induced decreases in BRCA1 expression and the consequent suppression of homologous recombination may lead to genetic instability. However, nothing is yet known about the involvement of BRCA2 in hypoxic conditions in breast cancer. Initially, a cell proliferation assay allowed us to hypothesize that hypoxia could negatively regulate the breast cancer cell growth in short term in vitro studies. Subsequently, we analyzed gene expression in breast cancer cell lines exposed to hypoxic condition by microarray analysis. Interestingly,…

Mechanisms of human DNA repair: an update.

2003

The human genome, comprising three billion base pairs coding for 30000-40000 genes, is constantly attacked by endogenous reactive metabolites, therapeutic drugs and a plethora of environmental mutagens that impact its integrity. Thus it is obvious that the stability of the genome must be under continuous surveillance. This is accomplished by DNA repair mechanisms, which have evolved to remove or to tolerate pre-cytotoxic, pre-mutagenic and pre-clastogenic DNA lesions in an error-free, or in some cases, error-prone way. Defects in DNA repair give rise to hypersensitivity to DNA-damaging agents, accumulation of mutations in the genome and finally to the development of cancer and various metab…

Skills for competitiveness: an empirical analysis of the educational provision for oenologists offered by Italian universities

2022

Purpose: Whilst operating in the context of a high-income economy, the Italian labour market is affected by the considerable challenges of vertical mismatch, skill gaps and skill shortages. In such a context, the aim of this empirical study is to explore current university provision regarding the formal qualification of the oenologist, in order to assess its alignment with the professionalism demands from the wine sector. Design/Methodology/Approach: The following was deployed to analyse university provision with a mixed method approach including social network analysis, cluster analysis and desk analyses based on descriptive statistics. Findings: The comparative analysis outlined in the re…

Load mismatch of grid-connected photovoltaic systems: Review of the effects and analysis in an urban context

2013

Abstract The mismatch between generated and consumed electricity is a relevant topic of the energy and economic assessment of photovoltaic (PV) systems. Due to the load mismatch some amount of PV electricity may be exported to the grid because the electrical demand is temporarily lower than production, whereas a consumption, which is higher than production and/or that does not match the available PV generation, will require to be supplemented by the public grid electricity. The presence of the load mismatch can cause the effect of disadvantageously purchasing electricity from the grid and/or squandering the unexploited PV energy. If only a very small part of the PV generation is used to sup…

Repair of O(6)-methylguanine is not affected by thymine base pairing and the presence of MMR proteins.

2001

Methylation at the O(6)-position of guanine (O(6)-MeG) by alkylating agents is efficiently removed by O(6)-methylguanine-DNA methyltransferase (MGMT), preventing from cytotoxic, mutagenic, clastogenic and carcinogenic effects of O(6)-MeG-inducing agents. If O(6)-MeG is not removed from DNA prior to replication, thymine will be incorporated instead of cytosine opposite the O(6)-MeG lesion. This mismatch is recognized and processed by mismatch repair (MMR) proteins which are known to be involved in triggering the cytotoxic and genotoxic response of cells upon methylation. In this work we addressed three open questions. (1) Is MGMT able to repair O(6)-MeG mispaired with thymine (O(6)-MeG/T)? (…

HUMAN LIVER AND MICRORNA PROFILING:EFFECTS OF DONOR AND RECIPIENT AGE-MISMATCH IN TRASPLANT.

2012

Impact of Prosthesis-Patient Mismatch after Mitral Valve Replacement

2016

Background and aim of the study: The study aim was to determine the impact of prosthesis-patient mismatch (PPM) on early and late clinical outcomes, left atrial and ventricular remodeling, late tricuspid valve regurgitation and pulmonary hypertension (PH) in patients after mitral valve replacement (MVR). Methods: A total of 46 patients (mean age 66 ± 9.3 years) with mitral valve diseases and undergoing isolated MVR was enrolled in the study. The mitral valve effective orifice area (EOA) was determined using the continuity equation and indexed for the patient’s body surface area (EOAi). PPM was defined as EOAi ≤1.2 cm2/m2. PH was defined as a systolic pulmonary artery pressure (sPAP) >40 mmH…

Improving point matching on multimodal images using distance and orientation automatic filtering

2016

International audience; Speed Up Robust Features SURF is one of the most popular and efficient methods used for image registration task. In order to achieve a correct registration, a good matching of feature point is required. However in the case of multimodal images, the high and non-linear intensity changes between different modalities led to many outliers (mismatching of detected points) and consequently a fail in the registration. Therefore, in this paper we introduce an efficient method devoted to the detection and removal of such outlier. It's based on an automatic filtering of outliers on both distance and orientation between features points. We tested our proposed method on a set of…

Experiments Meet Hydrophobic Mismatch: A Re-evaluation Of The Orientation Of Model Transmembrane Peptides From Solid-State NMR

2009

The basic physical rules underlying the organization of biological membranes can be gathered under the simple, but powerful, concept of hydrophobic mismatch. For example, the mutual adjustment of the lipid and protein hydrophobic lengths can be related with the existence of lipid rafts and explain discrete secretory pathways in the Golgi apparatus. The orientation of membrane protein fragments is predicted to follow the same hydrophobic mismatch principles, as illustrated by some experiments and molecular dynamics simulations. However, this appears to be challenged by results of solid-state 2H NMR experiments on model transmembrane peptides, displaying tilt angle values unexpectedly small a…