Publications by authors named "Siegfried Knasmuller"

The presence of two new disinfectant by-product (DBP) groups in the UK was recently shown using non-target analysis, halogenated-hydroxycyclopentenediones and halogenated-methanesulfonic acids. In this work, we confirmed the structure of 2,2,4-tribromo-5-hydroxycyclopent-4-ene-1,3-dione (TBHCD), and quantified it together with dibromomethanesulfonic acid at 122 ± 34 and 326 ± 157 ng L on average in London's drinking water, respectively (n = 21). We found TBHCD to be photolabile and unstable in tap water and at alkaline pH.

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  • Micronucleus (MN) assays using buccal cells are effective for assessing genetic damage in workers exposed to genotoxic metals, with most studies showing increased MN and nuclear anomalies among various occupations.
  • A comprehensive review of 73 studies, mainly from South East Asia and South America, highlighted the need for better evaluation methods, as many studies lacked thorough assessments of genetic stability and cytotoxic effects.
  • The data suggests that MN assays can provide valuable insights into chromosomal damage from metal exposure, complementing current chemical analysis and potentially enhancing workplace safety by reflecting biological impacts.
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Several human studies indicate that mobile phone specific electromagnetic fields may cause cancer in humans but the underlying molecular mechanisms are currently not known. Studies concerning chromosomal damage (which is causally related to cancer induction) are controversial and those addressing this issue in mobile phone users are based on the use of questionnaires to assess the exposure. We realized the first human intervention trial in which chromosomal damage and acute toxic effects were studied under controlled conditions.

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  • - The comet assay is a flexible method used to identify DNA damage in individual eukaryotic cells, applicable to various species from yeast to humans, detecting issues like DNA strand breaks and other forms of damage.
  • - Modifications to the protocol are necessary based on the specimen to minimize additional DNA damage during sample processing and to enhance the detection of damage differences.
  • - The method has been validated for various applications in research and has gained recognition as an in vivo genotoxicity test by the OECD, with guidelines provided for its use across different cell types and DNA damage assessments.
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Consumption of very hot beverages and foods increases the incidence of oral and esophageal cancer but the mechanisms are not known and the critical temperature is not well defined. We realized a study with exfoliated cells from the oral cavity of individuals (n = 73) that live in an area in Iran which has the highest incidence of EC worldwide. Consumption of beverages at very high temperatures is a characteristic feature of this population.

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  • - About 40 million workers are exposed to crystalline silica (CS), a known human carcinogen, which can damage genetic material and potentially lead to cancer formation due to inflammation and reactive oxygen species.
  • - A systematic review identified 13 studies that mostly found increased levels of micronuclei and DNA damage in workers exposed to CS, particularly among potters, stone cutters, miners, and construction workers.
  • - Although results show that CS exposure can lead to genetic damage, many studies lack detailed exposure information and particle characteristics, making it difficult to establish global occupational exposure limits. However, these studies can help evaluate health impacts related to DNA instability in specific jobs.
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The small-molecule E26 transformation-specific (ETS) factor inhibitor YK-4-279 was developed for therapy of ETS/EWS fusion-driven Ewing's sarcoma. Here we aimed to identify molecular factors underlying YK-4-279 responsiveness in ETS fusion-negative cancers. Cell viability screenings that deletion of induced hypersensitization against YK-4-279 especially in the BRAF-mutated colon cancer model RKO.

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During the harvest period, tobacco workers are exposed to nicotine and it is known that absorption of the alkaloid via the leaves causes green tobacco sickness (GST). We investigated if GST and its symptoms are associated with DNA damage and alterations of the redox status. DNA damage was measured in lymphocytes of tobacco workers and controls (n = 40/group) in single cell gel electrophoresis assays.

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Cervical cancer (CC) is the fourth most common cancer in women; the survival rates depend strongly on its early detection. The Pap test is the most frequently used diagnostic tool, but due to its limited sensitivity/specificity, additional screening tests are needed. Therefore, we evaluated the use of micronucleus (MN) assays with cervical cells for the prediction and diagnosis of CC.

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Metastatic cancer cells cross endothelial barriers and travel through the blood or lymphatic fluid to pre‑metastatic niches, leading to their colonisation. 'S' stereoisomer 12S‑hydroxy‑5Z,8Z,10E,14Z‑eicosatetraenoic acid [12(S)‑HETE] is secreted by a variety of cancer cell types and has been indicated to open up these barriers. In the present study, another aspect of the endothelial unlocking mechanism was elucidated.

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The purpose of this study was to investigate the effect of six months strength training with or without supplementing protein and vitamins, on chromosomal integrity of buccal cells in institutionalized elderly. One hundred seventeen women and men (65-98 years) performed either resistance training (RT), RT combined with a nutritional supplement (RTS) or cognitive training (CT) twice per week for six months. Participants' fitness was measured using the 6 min walking, the chair rise, and the handgrip strength test.

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  • * Researchers conducted micronucleus assays using nasal and buccal cells from 42 road workers and 42 control subjects, finding significant increases in markers of chromosomal damage in workers' cells.
  • * Results suggest that prolonged exposure (over 10 years) to chemicals like silica dust and benzoyl peroxide may contribute to genetic damage, recommending further studies on the cancer risks for these workers.
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Scope: Obesity causes DNA damage, which is causally related to several disorders including cancer, infertility, and cognitive dysfunctions. The aim of this study is to investigate whether weight loss improves the integrity of the genetic material.

Methods And Results: Overweight mice are fed ad libitum either with a Western diet (WD), with a 40% caloric restricted WD, or with a high carbohydrate low protein (HCLP) diet.

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Methamphetamine (METH) is a widely consumed psychostimulant drug; its acute toxic effects in brain and liver are well known, furthermore, there is some evidence in regard to its DNA damaging properties in humans. Therefore, we studied the impact of the drug on genomic stability in human derived hepatoma (HepG2) cells, which reflect the activation/detoxification of drugs better than other cell lines. Furthermore, experiments with human buccal derived cells (TR146) were conducted as the drug is consumed orally.

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Acid Black 10B (AB10B) is widely used for the production of textiles, leather and prints. It is a representative of azo dyes and it is well documented that some of these compounds are mutagenic per se, and that cleavage products (in particular aromatic amines) may cause damage of the genetic material and cancer. Since no toxicological data on AB10B have been published, we evaluated its mutagenic activity in Salmonella/microsome assays and studied its acute toxic and genotoxic properties in a human derived liver cell line (HepG2) which retained the activities of drug metabolizing enzymes.

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  • The study aimed to determine if longer work hours affect DNA stability, telomere length, and inflammation in office workers and carpenters.
  • After changing their schedules from 8 to 12 hours over three months, no significant damage to DNA or changes in telomere length or inflammatory markers were observed overall.
  • However, younger workers (ages 21-30) showed a slight increase in C-reactive protein (CRP) levels, suggesting potential health risks for this age group due to extended work hours.
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Cannabidiol (CBD) and cannabidivarin (CBDV) are natural cannabinoids which are consumed in increasing amounts worldwide in cannabis extracts, as they prevent epilepsy, anxiety, and seizures. It was claimed that they may be useful in cancer therapy and have anti-inflammatory properties. Adverse long-term effects of these drugs (induction of cancer and infertility) which are related to damage of the genetic material have not been investigated.

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Health authorities are alarmed worldwide about the increase of obesity and overweight in the last decades which lead to adverse health effects including inflammation, cancer, accelerated aging and infertility. We evaluated the state of knowledge concerning the impact of elevated body mass on genomic instability. Results of investigations with humans (39 studies) in which DNA damage was monitored in lymphocytes and sperm cells, are conflicting and probably as a consequence of heterogeneous study designs and confounding factors (e.

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Purpose: Aim of the study was to find out if gallic acid (GA), a common phenolic in plant foods, prevents obesity induced DNA damage which plays a key role in the induction of overweight associated cancer.

Methods: Male and female C57BL6/J mice were fed with a low fat or a high fat diet (HFD). The HFD group received different doses GA (0, 2.

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Some epidemiological studies indicate that the use of mobile phones causes cancer in humans (in particular glioblastomas). It is known that DNA damage plays a key role in malignant transformation; therefore, we investigated the impact of the UMTS signal which is widely used in mobile telecommunications, on DNA stability in ten different human cell lines (six brain derived cell lines, lymphocytes, fibroblasts, liver and buccal tissue derived cells) under conditions relevant for users (SAR 0.25 to 1.

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Patients with inflammatory bowel disease (IBD) have a higher risk of developing colitis-associated-cancer (CAC); however, the underlying processes of disease progression are not completely understood. Here, the molecular processes of inflammation-driven colon carcinogenesis were investigated using IL10-deficient mice (IL10 KO). IL10 KO mice were euthanized after development of colitis and dysplasia.

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Cell lines which are currently used in genotoxicity tests lack enzymes which activate/detoxify mutagens. Therefore, rodent-derived liver preparations are used which reflect their metabolism in humans only partly; as a consequence misleading results are often obtained. Previous findings suggest that certain liver cell lines express phase I/II enzymes and detect promutagens without activation; however, their use is hampered by different shortcomings.

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Microsatellite instability (MSI) is present in ulcerative colitis (UC) and colitis-associated colorectal cancers (CAC). Certain factors released by polymorphonuclear cells (PMNs) may drive mucosal frameshift mutations resulting in MSI and cancer. Here, we applied a co-culture system with PMNs and colon epithelial cells to identify such culprit factors.

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A potential contribution of H. pylori contamination to low-grade inflammation, oxidative stress (OS) and insulin resistance as well as correlations between these parameters in asymptomatic sedentary males was analysed. We enrolled 30 apparently healthy asymptomatic young subjects (18 H.

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Obesity is associated with low-grade inflammation, increased ROS production and DNA damage. Supplementation with antioxidants might ameliorate DNA damage and support epigenetic regulation of DNA repair. C57BL/6J male mice were fed a high-fat (HFD) or a control diet (CD) with and without vitamin E supplementation (4.

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