Search results for "excision"

Expression of the human XPB/ERCC-3 excision repair gene-homolog in the sponge Geodia cydonium after exposure to ultraviolet radiation.

1998

Abstract The marine demosponge Geodia cydonium encodes a gene, termed GCXPB , which displays 62% identity to the human XPB/ERCC-3 gene that specifically corrects the repair defect in xeroderma pigmentosum and in Cockayne's syndrome. The cDNA was isolated and characterized the deduced aa sequence, XPB_GEOCY, with the calculated size of 91,541 Da comprises the characteristic domains found in the related helicases. Phylogenetic tree analysis revealed that the sponge sequence is grouped to the metazoan related XPB/ERCC-3 polypeptides. Northern Blot analyses have been performed with sponge samples collected at different depths, thus exposed to different intensities of UV sunlight in the field. T…

Polymorphisms in DNA repair genes modulate survival in cisplatin/gemcitabine-treated non-small-cell lung cancer patients.

2006

Abstract Background: Impaired DNA repair capacity may favorably affect survival in cisplatin/gemcitabine-treated non-small-cell lung cancer (NSCLC) patients. We investigated the association of survival with genetic polymorphisms in X-ray repair cross-complementing group 1 and group 3 (XRCC3), xeroderma pigmentosum group D (XPD), excision repair cross-complementing group 1, ligase IV, ribonucleotide reductase, TP53, cyclooxygenase-2, interleukin-6, peroxisome proliferator-activated receptor γ, epidermal growth factor, methylene-tetra-hydrofolate reductase and methionine synthase. Patients and methods: One hundred and thirty-five stage IV or IIIB (with malignant pleural effusion) NSCLC patien…

BER, MGMT, and MMR in defense against alkylation-induced genotoxicity and apoptosis

2001

Methylating carcinogens and cytostatic drugs induce different methylation products in DNA. In cells not expressing the repair protein MGMT or expressing it at a low level, O6-methylguanine is the major genotoxic, recombinogenic, and apoptotic lesion. Genotoxicity and apoptosis triggered by O6-methylguanine require mismatch repair (MMR). In cells expressing O6-methylguanine-DNA methyl transferase (MGMT) at a high level or for agents producing low amounts of O6-methylguanine, N-alkylations become the major genotoxic lesions. N-Alkylations are repaired by base excision repair (BER). In mammalian cells, naturally occurring mutants of BER have not been detected, which points to the importance of…

RNase H1 and H2 are differentially regulated to eliminate RNA-DNA hybrids

2019

SUMMARYRNA-DNA hybrids are tightly regulated to ensure genome integrity. The RNase H enzymes, RNase H1 and H2, contribute to chromosomal stability through the removal of RNA-DNA hybrids. Loss of RNase H2 function is implicated in human diseases of the nervous system and cancer. To better understand RNA-DNA hybrid dynamics, we have focused on elucidating the regulation of the RNase H enzymes themselves. Using yeast as a model system, we demonstrate that RNase H1 and H2 are controlled in different manners. RNase H2 is regulated in a strict cell cycle dependent manner, both in terms of its R-loop removal, and ribonucleotide excision repair functions. RNase H1, however, can function independent…

Interaction of antimutagenic 1,4-dihydropyridine AV-153-Na with DNA and DNA-damaging molecules and its impact on DNA repair activity

2017

1,4-dihydropyridines (1,4-DHP) possess important biochemical and pharmacological properties, including antioxidant and antimutagenic activities. Interaction of some 1,4-DHP with DNA was recently reported. AV-153-Na, an antimutagenic and DNA-repair-enhancing compound appeared to be able to interact with DNA by intercalation. The aim of the current study was to characterize DNA’s capacity for the binding of AV-153-Na, and using different approaches, to test intracellular distribution of the compound, to test the ability of the compound to scavenge peroxynitrite and hydroxyl radical and to assess the ability of the compound to modify the activity of DNA repair enzymes. The DNA binding activity…

Induction of DNA Repair Genes in Mammalian Cells in Response to Genotoxic Stress

2006

Genotoxic agents provoke the activation of receptor-triggered pathways and DNA damage-related functions. Here we review data on immediate-early cellular responses and transcriptional activation of DNA repair genes following exposure of mammalian cells to genotoxic stress. Functional consequences of induction of DNA repair genes are also briefly discussed.

SURGICAL INNOVATION IN COLON CANCER: STUDY OF ROLE OF LAPAROSCOPY IN COMPLETE MESOCOLIC EXCISION (CME) FOR RIGHT-SIDED COLON CANCER. FEASIBILITY, SAF…

2021

Surgical treatment of early breast cancer in day surgery.

2007

Quadrantectomy and associated sentinel lymph node biopsy (SLNB) is currently employed in most breast surgery centres as the gold standard in the treatment of early breast cancer. This approach has a modest morbidity and can usually be performed in a day-surgery regimen, leading to best acceptance by the patients. This reports outlines the experience of our Breast Unit with quadrantectomy and SLNB in day surgery for early breast cancer. One hundred patients presenting to our institution with primary invasive breast cancer measuring less than 3 cm and clinically negative axillary nodes underwent quadrantectomy and SLNB in day surgery. For 60 women with breast cancer the sentinel node was nega…

Total mesorectal excision - does the choice of dissection technique have an impact on pelvic autonomic nerve preservation?

2011

Background The aim of this experimental study was to assess the quality of pelvic autonomic nerve preservation of different dissection techniques.

Pelvic Autonomic Nerve Preservation during Total Mesorectal Excision (TME) from Werner Kneist

2017

According to the German guideline for “Colorectal Cancer,” total mesorectal excision (TME) removes the cancer located at the central and lower thirds of the rectum and the pelvic floor while preserving the superior hypogastric plexus (SHP), the hypogastric nerves, and the inferior hypogastric plexus (IHP) (recommendation level A, level of evidence 1b, strong consensus). Intraoperative nerve damage is to be avoided to preserve postoperative quality of life with the premise of radical surgery. It is particularly necessary to preserve autonomously controlled urogenital and anorectal functions. Among other things, this presumes a fundamental understanding of current events on surgical topograph…