Search results for "DNA damage"
showing 10 items of 534 documents
Assessment of the cytotoxic potential of an aqueous-ethanolic extract from Thalassia testudinum angiosperm marine grown in the Caribbean Sea
2018
Abstract Objectives Reported antioxidant, anti-inflammatory and neuroprotective properties for one aqueous-ethanolic extract from Thalassia testudinum which grows in the Caribbean Sea compelled us to explore about extract cytotoxic effects. Methods Cell viability was assayed on tumour (HepG2, PC12, Caco-2 and 4T1) and non-tumour (VERO, 3T3, CHO, MCDK and BHK2) cell lines. The extract effects upon primary cultures of rat and human hepatocytes and human lymphocytes were assayed. Key findings The extract exhibited cytotoxicity against cancer cells compared to normal cells, and the IC50 values were 102 μg/ml for HepG2, 135 μg/ml for PC12, 165 μg/ml for Caco-2 and 129 μg/ml for 4T1 cells after 4…
Blood levels of nitric oxide and DNA breaks assayed in whole blood and isolated peripheral blood mononucleated cells in patients with multiple sclero…
2019
Abstract Oxidative stress, especially overproduction of nitric oxide (NO), is considered to be one of the crucial factors in the pathogenesis of multifactorial multiple sclerosis (MS). DNA breaks could be one of the consequences of oxidative stress; however, data on DNA breakage in MS are very few and contradictory. There are no data on direct measurements of NO production in the blood of MS patients. The goal of this study was to determine the level of single-stranded DNA breaks in whole blood or isolated peripheral blood mononuclear cells (PBMNCs) by means of alkaline single cell gel electrophoresis (comet assay) and to evaluate production of NO in the human blood by applying electron par…
Correlation between the DNA fragmentation index (DFI) and sperm morphology of infertile patients
2020
Abstract Purpose To evaluate the correlation between the DNA Fragmentation Index (DFI) and sperm morphology in patients undergoing ICSI, as a predictive parameter in reproductive outcomes. Methods A retrospective study was conducted on 125 infertile patients enrolled in a fertility clinic. Seminal characteristics were measured following the WHO guidelines (2010) for the examination of the seminal fluid. After collecting motile sperm population by pellet swim up, DFI was calculated and simultaneously associated with sperm morphology using in situ TUNEL assay and an image analyzer software in at least 250 spermatozoa for each patient. Results All subjects were divided into two groups accordin…
A Putatively Functional Haplotype in the Gene Encoding Transforming Growth Factor Beta-1 as a Potential Biomarker for Radiosensitivity
2011
Purpose To determine whether genetic variability in TGFB1 is related to circulating transforming growth factor-β1 (TGF-β1) plasma concentrations after radiotherapy and to radiosensitivity of lymphoid cells. Patients and Methods Transforming growth factor-β1 plasma concentrations ( n = 79) were measured in patients 1 year after radiotherapy and chromosomal aberrations ( n = 71) ex vivo before therapy start. Furthermore, TGF-β1 secretion and apoptosis were measured in isolated peripheral blood mononuclear cells of 55 healthy volunteers. These phenotypes were analyzed in relation to five germline polymorphisms in the 5′ region of the TGFB1 gene. Because of high linkage disequilibrium, these fi…
Increasing rates of DNA single-strand breaks in lymphocytes of clinical personnel handling cytostatic drugs
1993
A total of 27 persons, working in cancer stations with exposure to cytostatics, and 40 healthy control persons were examined for DNA single-strand breaks in peripheral lymphocytes. Non-smoking personnel from cancer stations were found to have an increased rate of DNA single-strand breaks compared to the non-smoking control subjects. In the case of smokers an increased rate of DNA single-strand breaks could be recorded for those working in cancer stations as well as with the controls. DNA single-strand breaks indicate reversible damage to DNA. As DNA repair is not perfect in every case, an increased number of DNA single-strand breaks leads to irreversible DNA damage.
Biodosimetry Based on γ-H2AX Quantification and Cytogenetics after Partial- and Total-Body Irradiation during Fractionated Radiotherapy
2015
The aim of this current study was to quantitatively describe radiation-induced DNA damage and its distribution in leukocytes of cancer patients after fractionated partial- or total-body radiotherapy. Specifically, the impact of exposed anatomic region and administered dose was investigated in breast and prostate cancer patients receiving partial-body radiotherapy. DNA double-strand breaks (DSBs) were quantified by γ-H2AX immunostaining. The frequency of unstable chromosomal aberrations in stimulated lymphocytes was also determined and compared with the frequency of DNA DSBs in the same samples. The frequency of radiation-induced DNA damage was converted into dose, using ex vivo generated ca…
Occupational exposure to metal-rich particulate matter modifies the expression of repair genes in foundry workers
2021
Foundry workers are exposed to numerous occupational health hazards, which may result in increased risk of cancer, respiratory disease, and other diseases. Oxidative stress is known to be involved in the pathogenesis of such diseases. The present study aimed to investigate the association between multiple occupational exposures in foundry workers and expression of deoxyribonucleic acid (DNA) repair genes as a biomarker of oxidative DNA damage. The study sample comprised 17 foundry workers and 27 matched control subjects. Expression of 8-oxoguanine DNA glycosylase-1 (OGG1), inosine triphosphate pyrophosphate (ITPA), and MutT homolog 1 (MTH1) in peripheral blood was examined using the real-t…
Long-time expression of DNA repair enzymes MGMT and APE in human peripheral blood mononuclear cells.
2001
The DNA repair enzymes O6-methylguanine-DNA methyltransferase (MGMT) and apurinic/apyrimidinic endonuclease (APE, also known as Ref-1) play an important role in cellular defense against the mutagenic and carcinogenic effects of DNA-damaging agents. Cells with low enzyme activity are more sensitive to induced DNA damage and may confer a higher carcinogenic risk to the individuals in question. To study the level of variability of MGMT and APE expression in human, we analyzed in a long-time study MGMT and APE expression in peripheral blood mononuclear cells (PBMC) from healthy individuals. The data revealed high inter- and intraindividual variability of MGMT but not of APE. For MGMT, the inter…
Cytotoxic and genotoxic effects of electronic cigarette liquids on human mucosal tissue cultures of the oropharynx
2016
The popularity of electronic cigarettes (ECs) is rapidly growing and ECs are claimed to be an uncritically regarded alternative to conventional cigarettes. The mucosal tissue of the upper aerodigestive tract (UADT) is the first contact organ for xenobiotics such as liquids of ECs. The aim of this study is to investigate the bimolecular effects of e-liquids on human pharyngeal tissue cultures to evaluate whether e-liquids and their components present a risk factor for head and neck squamous cell carcinoma. Fresh tissue samples of healthy oropharyngeal mucosa were assembled into mucosal tissue cultures. Two fruit-flavored liquids (FLs), one tobacco-flavored liquid (TL) (all containing nicotin…
Acute effects of strength exercises and effects of regular strength training on cell free DNA concentrations in blood plasma.
2017
Creatine kinase (CK) is a marker for muscle cell damage with limited potential as marker for training load in strength training. Recent exercise studies identified cell free DNA (cfDNA) as a marker for aseptic inflammation and cell damage. Here we overserved in a pilot study the acute effects during strength exercise and chronic effects of regular strength training on cfDNA concentrations over a period of four weeks in three training groups applying conservation training (CT) at 60% of the 1 repetition maximum, high intensity-low repetition training (HT) at 90% of the 1 repetition maximum and differential training (DT) at 60% of the 1 repetition maximum. EDTA-plasma samples were collected b…