View clinical trials related to DNA Damage.
Filter by:We envisioned a scenario where the interaction between the ATM-Chk2/ATR-Chk1 pathways and Hippo enables GC cells to overcome chemotherapy-induced death stimuli. First, ATM-Chk2 and ATR-Chk1 were found to be activated across all the GC molecular subtypes. Moreover, a number of genes associated with their basal activation are recurrently mutated or amplified. Thus, we retrospectively characterized a cohort of GC patients treated with first-line therapy for DDR- and Hippo-related markers, identifying a signature predicting inferior PFS and OS. This exploratory analysis provided the necessary information (frequency of candidate biomarkers and effect difference between groups) for a prospective study with validation purposes, which is the main goal of this trial.
The remarkable therapeutic anticaries effect of fluoride is well recognized, but in recent years, toxic effects on the oral mucosa have been discussed. So far, many in vivo studies examining the genotoxic and cytotoxic effect of fluoride in human cells (lymphocytes, bone marrow, germ cells) have been carried out, but there are no studies examining the effect of fluoride on cells of the buccal mucosa. In vitro studies have shown that sodium fluoride can be toxic to fibroblasts of the oral mucosa by inhibiting protein synthesis, suppressing mitochondrial function and consequently reducing the amount of intracellular ATP. The study would include 80 participants, aged between 18 and 75. All subjects would use the same toothpaste without fluoride for the first month, and then they would be randomly divided into four groups, where three groups would receive a toothpaste with fluoride with one of the active substances (sodium fluoride, sodium monofluorophosphate, amine fluoride) for the next 60 days, while the control group would continue to use the toothpaste without fluorine. Swabs of the buccal mucosa would be taken at 0 (before the start of use) and 30, 45 and 60 days after the start of using the tested toothpastes. The aim of this research would be to examine the cytotoxic and genotoxic effect of toothpastes containing fluoride with different active substances and to compare their effect. As a measure of genotoxicity and cytotoxicity in cells, the micronucleus test will be used.
Deoxyribonucleic acid (DNA) damage of granulosa cells obtained during oocyte retrieval will be evaluated by flow cytometry with detection of Histone H2A.X and Phosphorylated Gamma H2A.X protein levels in patients with low ovarian reserve and unexplained infertile patients as a control group undergoing intracytoplasmic sperm injection (ICSI) treatment. Fertilization, embryo quality, transfer rate, implantation, clinical pregnancy will be recorded as well as demographic data. DNA damage of granulosa cells will be compared between two groups. The effect of DNA damage of granulosa cells on fertilization, quality of oocyte and embryo, implantation, and clinical pregnancy will be also evaluated.
Breast and Ovarian Cancer Syndrome (HBOC) is characterized by mutations in tumor suppressor genes such as BRCA1 and BRCA2, which increase the carrier's risk of developing breast and ovarian cancer, especially before 40. In this pathology the DNA damage is increased because there is a state of chronic inflammation, plus the antineoplastic treatments and changes in body composition result in oxidative stress. The inductions of epigenetic changes by a nutritional intervention with an specific distribution of macronutrients, micronutrients and polyphenols, not only ensures an optimal nutritional status, but also shows a decrease in oxidative stress, and therefore in DNA damage. The aim of this study is to assess if the DNA damage in patients with HBOC decreases after the nutritional intervention.
Purpose of the experiment The investigators know that DNA damage is formed in the skin by sun exposure of the thymine-dimer type. Many of these injuries are repaired and excreted through the urine. The purpose of the study is to quantify DNA damage in the urine after ultraviolet (UV) irradiation of the skin in healthy subjects. The investigators would like to investigate which day after two different irradiation regimens the highest secretion of thymine dimers occurs. If the investigators establish such a test system, it will be possible to test potential photoprotective substances or potential photocarcinogenic substances. Method of the experiment, design, and examination procedures The subjects (n = 16-20) are recruited by a post on Bispebjerg's hospital website. Based on this, subjects are divided into 2 groups of 8-10 people. Group 1 is irradiated 3 times with 1 standard erythema dose (SED). 1 SED corresponds to approx. 10 minutes sun around 13 pm on a good Danish summer day. Group 2 is irradiated once with 3 SED, which corresponds to approx. 30 minutes around 13 pm on a good Danish summer day. The irradiation is carried out on day 1 for group 2 and days 1, 2 and 3 for group 1. Subjects are irradiated in a full-body UV cabin (Waldmann, Willing-Schwenningen, Germany) with 26 F85 / 100W UV6 tubes (290-350 nm, broad-spectrum). 13 seconds of illumination, equivalent to 1 SED. The subjects are standing in the cabin and have a screen on so that their eyes and face are not exposed to radiation. When irradiated, the subjects must only wear underwear, which for men are underpants/boxer shorts, while for women it is bras and panties. The experiment is performed between October and March, to avoid that the subjects do not simultaneously receive UV radiation from the sun and thus form DNA damage. Subjects must collect morning urine in dispensed containers and must store it in their own freezer until the final visit. Morning urine (2x 50 mL) is collected before irradiation, called day 1, and even until day 8 after the last exposure, ie. day 10 for group 1 and day 8 for group 2. Before the first exposure, pigment and redness are measured on the subjects. Pigment and redness measurements are performed on the back, chest, and shoulder.
The purpose of this study is to evaluate if the anesthetics propofol and desflurane can damage DNA according to comet essay in patients submitted to lumbar disc surgery.
The purpose of this study is to demonstrate the molecular effect of desflurane on DNA by measuring the global DNA methylation level in patients under going lumbar spinal stenosis surgery under general anesthesia.
Obesity leads to physiological imbalance resulting in hyperglycemia, dyslipidaemia and inflammation and can generate systematic oxidative stress through multiple biochemical mechanisms. Oxidative stress (OS) can induce DNA damage and inhibit DNA repair mechanisms. Very low calorie diet (VLCD) have rapid positive effect on weight loss, glucose homeostasis, insulin resistance, inflammation and OS. The aim of this study is to determine the effect of a three-week VLCD on anthropometric, biochemical and genomic parameters in individuals with BMI ≥ 35kg/m2.
Obesity manifest with inflammation, hyperglycaemia and dyslipidaemia. These conditions disturb redox system by generating excessive reactive oxygen species (ROS) and causing oxidative stress (OS) leading to DNA damage. Very low calorie diet (VLCD) have rapid positive effect on weight loss, glucose homeostasis, inflammation and OS. The aim of study is to test the influence of 3-weeks VLCD on anthropometric, biochemical and genomic parameters in class II and III obesity patients.
Buccal cells represent the first barrier to the oral hygiene products' potential toxic effect. The usual concentration of fluoride in toothpastes is 1000/1100 parts per million (ppm F); toothpastes with higher (1500 ppm F) and lower than conventional fluoride levels (around 500 ppm F) are available in many countries. Toothpastes containing higher concentrations of fluoride confer greater protection against caries but at the same time the fluoride is able to induce harmful effects on oral mucosa cells. The study would include around 40 participants, aged between 20 and 65, divided in two groups. Each group will use fluoride free toothpaste for 28 days, than afterwards group B will get toothpastes (each for 28 days) with no fluoride, 1045 ppm F and 1450 ppm F used together with mouthrinse containing 450 ppm F, while the group A will have everything the same except the mouthrinse that will contain no fluoride - a placebo mouthrinse. Every 28 days buccal cells samples would be collected from each participant and a Buccal micronucleus cytome assay would be performed according to Nature protocols: Thomas et all. The aim of this study would be to assess the possible cumulative effect of together use of fluoridated toothpastes and mouthrinses, since population worldwide uses them together without any exact studies about toxicity.