scholarly journals Effects of photopolymerisation on genotoxicity of composite adhesives in the comet assay

Genetika ◽  
2016 ◽  
Vol 48 (2) ◽  
pp. 617-627
Author(s):  
Stefan Dacic ◽  
Ninoslav Djelic ◽  
Milena Radakovic ◽  
Nada Lakic ◽  
Aleksandar Veselinovic ◽  
...  
Keyword(s):  
Dna Damage ◽  
Comet Assay ◽  
Human Lymphocytes ◽  
Negative Control ◽  
In Vivo Studies ◽  
Halogen Lamp ◽  
Genotoxic Effects ◽  
Significant Difference ◽  
Isolated Human Lymphocytes

Certain in vivo studies have shown that the application of adhesives directly onto the open pulp or on a thin layer of dentin causes inflammation and pulpal abscesses. This reaction is related to toxic effects of monomers from adhesives. It has been confirmed that after proper illumination the adhesives become less toxic. The aim of the study was to examine genotoxicity of non-polymerised, partly polymerised and polymerised adhesives on isolated human lymphocytes using the alkaline Comet assay. Adper Single bond2 and Adper Easy One/3M ESPE adhesive photopolymerisation was performed by Elipar Highlight 3M ESPE halogen lamp for 0, 10 and 40 sec, at final concentrations of 100, 200, 500 and 1000 ?g/mL. With both adhesives, photopolymerisation at 0 and 10 seconds showed statistically significant increase in DNA damage in comparision to the negative control (solvent). On the other hand, after 40 seconds of photopolymerisation of both adhesives in all tested concentrations, the degree of DNA damage in Comet assay had no significant difference (P>0.05, ?2 test) compared to the negative control. Therefore, only the 40 seconds of photopolymerisation prevented genotoxic effects of both adhesives in the Comet assay.

Cytogenetic Damage of Human Lymphocytes in Humanized Mice Exposed to Neutrons and X Rays 24 h After Exposure

2021 ◽  
Vol 161 (6-7) ◽  
pp. 352-361
Author(s):  
Qi Wang ◽  
Younghyun Lee ◽  
Monica Pujol-Canadell ◽  
Jay R. Perrier ◽  
Lubomir Smilenov ◽  
...  
Keyword(s):  
Dna Damage ◽  
Radiation Exposure ◽  
Human Lymphocytes ◽  
Absorbed Dose ◽  
Chromosome 1 ◽  
X Rays ◽  
Chromosomal Dna ◽  
Humanized Mouse Model ◽  
Significant Difference

Detonation of an improvised nuclear device highlights the need to understand the risk of mixed radiation exposure as prompt radiation exposure could produce significant neutron and gamma exposures. Although the neutron component may be a relatively small percentage of the total absorbed dose, the large relative biological effectiveness (RBE) can induce larger biological DNA damage and cell killing. The objective of this study was to use a hematopoietically humanized mouse model to measure chromosomal DNA damage in human lymphocytes 24 h after in vivo exposure to neutrons (0.3 Gy) and X rays (1 Gy). The human dicentric and cytokinesis-block micronucleus assays were performed to measure chromosomal aberrations in human lymphocytes in vivo from the blood and spleen, respectively. The mBAND assay based on fluorescent in situ hybridization labeling was used to detect neutron-induced chromosome 1 inversions in the blood lymphocytes of the neutron-irradiated mice. Cytogenetics endpoints, dicentrics and micronuclei showed that there was no significant difference in yields between the 2 irradiation types at the doses tested, indicating that neutron-induced chromosomal DNA damage in vivo was more biologically effective (RBE ∼3.3) compared to X rays. The mBAND assay, which is considered a specific biomarker of high-LET neutron exposure, confirmed the presence of clustered DNA damage in the neutron-irradiated mice but not in the X-irradiated mice, 24 h after exposure.

scholarly journals Genotoxic properties of fluorines (review)

2020 ◽  
Vol 99 (3) ◽  
pp. 253-258
Author(s):  
Е.Э. E. Калюжная ◽  
А.Ю. Yu. Просеков ◽  
Валентин Павлович Волобаев
Keyword(s):  
Dna Damage ◽  
In Vivo Studies ◽  
Hydroxyl Group ◽  
Fluoride Ion ◽  
Genotoxic Effects ◽  
Human Environment ◽  
Human Contact ◽  
Professional Contact

Introduction. Consistency of fluoride excess in the human environment and professional contact with fluoride is an actual and underestimated problem. Fluoride ion is able to displace the hydroxyl group in calcium hydroxyapatites, forming stable crystals of mixed form of apatites, inducing bone pathology, fluorosis. Despite the high prevalence of fluorosis, there are only a few studies discussing the ability of fluoride ion to increase the level of genotoxic effects. At the same time, such studies are in high demand in connection with a direct correlation between genetic instability and the risk of carcinogenesis. Material and methods. A literature search was conducted according the following queries: “fluoride, fluoride ion, fluorides, DNA damage, genetic damage, genotoxicity.” The search was conducted on the databases PubMed, MEDLINE, Embase and Google Scholar for various articles (all publications until June 2018). All publications were analyzed and included in this review. Results.The present review examines the results of studies aimed at investigation of the ability of fluoride to induce DNA damage, published since the 50-s of 20th century to the present. The analyse of data about genotoxic and mutagenic properties of fluorine observed in In vitro and In vivo studies is provided. It is summarized that at concentrations of sodium fluoride in drinking water of more than 1 mM, fluoride ion has the ability to induce DNA damage and increase the frequency of clastogenic effects in humans and large monkeys. At the same time, for a significant increase in genotoxic effects in rodents, large concentrations of fluorides are required. The main hypotheses about the mechanisms of the fluoride genotoxic properties are described. Conclusion. Considering results published nowadays, it can be noted that fluoride ion obviously showes a number of genotoxic features and can have mutagenic properties in case of chronic and direct contact with cellular objects. It remains questionable issue about genotoxic risk accompanied human contact with fluoride compounds.

scholarly journals Application of Comet assay to assess the effects of white bean meal on DNA of human lymphocytes

2012 ◽  
Vol 48 (1) ◽  
pp. 103-108 ◽  
Author(s):  
Luciana Lopes Silva Pereira ◽  
Silvana Marcussi ◽  
Lívia Cabral Sátiro ◽  
Chrystian Araujo Pereira ◽  
Larissa Fonseca Andrade ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Comet Assay ◽  
Human Lymphocytes ◽  
Negative Control ◽  
Genotoxic Effects ◽  
Future Studies ◽  
Bean Flour ◽  
White Bean ◽  
Bean Meal ◽  
Cellular Dna

This study was conducted to evaluate the potential induction of genotoxic effects of white bean flour using the Comet assay. The test was conducted with human lymphocytes present in whole blood immediately after collection, by incubation with white bean flour in three concentrations (3.92, 9.52 and 18.18 mg/mL) at 37 ºC for 4 h followed by preparation of slides. Samples were considered positive (above 20% damage) when the damage observed to cellular DNA was higher than the negative control. No genotoxic potential was found at the doses tested. However, it would be premature to suggest absence of risk to human health of DNA damage since the exposure of cells to the extract was restricted to four hours rather than a whole cell cycle. Additionally, further information on toxicology should be obtained in future studies.

scholarly journals GENOTOXIC PROPERTIES OF FLUORINES (REVIEW)

2020 ◽  
Vol 99 (3) ◽  
pp. 253-258
Author(s):  
E. E. Kalyuzhnaya ◽  
A. Yu. Prosekov ◽  
Valentin P. Volobaev
Keyword(s):  
Dna Damage ◽  
In Vivo Studies ◽  
Hydroxyl Group ◽  
Fluoride Ion ◽  
Genotoxic Effects ◽  
Human Environment ◽  
Human Contact ◽  
Professional Contact

Introduction. Consistency of fluoride excess in the human environment and professional contact with fluoride is an actual and underestimated problem. Fluoride ion is able to displace the hydroxyl group in calcium hydroxyapatites, forming stable crystals of mixed form of apatites, inducing bone pathology, fluorosis. Despite the high prevalence of fluorosis, there are only a few studies discussing the ability of fluoride ion to increase the level of genotoxic effects. At the same time, such studies are in high demand in connection with a direct correlation between genetic instability and the risk of carcinogenesis. Material and methods. A literature search was conducted according the following queries: “fluoride, fluoride ion, fluorides, DNA damage, genetic damage, genotoxicity.” The search was conducted on the databases PubMed, MEDLINE, Embase and Google Scholar for various articles (all publications until June 2018). All publications were analyzed and included in this review. Results.The present review examines the results of studies aimed at investigation of the ability of fluoride to induce DNA damage, published since the 50-s of 20th century to the present. The analyse of data about genotoxic and mutagenic properties of fluorine observed in In vitro and In vivo studies is provided. It is summarized that at concentrations of sodium fluoride in drinking water of more than 1 mM, fluoride ion has the ability to induce DNA damage and increase the frequency of clastogenic effects in humans and large monkeys. At the same time, for a significant increase in genotoxic effects in rodents, large concentrations of fluorides are required. The main hypotheses about the mechanisms of the fluoride genotoxic properties are described. Conclusion. Considering results published nowadays, it can be noted that fluoride ion obviously showes a number of genotoxic features and can have mutagenic properties in case of chronic and direct contact with cellular objects. It remains questionable issue about genotoxic risk accompanied human contact with fluoride compounds.

Assessment of Genotoxicity of Levosimendan in Human Cultured Lymphocytes

2019 ◽  
Vol 12 (2) ◽  
pp. 160-165 ◽  
Author(s):  
Abeer M. Rababa'h ◽  
Omar F. Khabour ◽  
Karem H. Alzoubi ◽  
Dua'a Al-momani ◽  
Mera Ababneh
Keyword(s):  
Dna Damage ◽  
Sister Chromatid ◽  
Oxidative Dna Damage ◽  
Human Lymphocytes ◽  
Sister Chromatid Exchanges ◽  
In Vivo Studies ◽  
Proliferation Index ◽  
Chromatid Exchanges ◽  
Anti Inflammation

Background and Objective: Levosimendan is a positive inotropic and a vasodilator agent with pleotropic characteristics that include antioxidation, anti-inflammation and smooth muscle vasodilation. Methods: In this study, the effects of levosimendan (0, 0.1, 1, 10, and 20 µg/ml) on oxidative DNA damage and sister-chromatid exchanges (SCEs) were evaluated in human cultured lymphocytes. Results: The results showed that levosimendan increased the frequency of SCEs in all examined concentrations (P<0.01) except for 0.1 µg/ml. On the other hand, levosimendan did not induce oxidative DNA damage as measured by the 8-OHdG biomarker (P > 0.05). In addition, neither mitotic arrest nor proliferation index was affected by levosimendan at all examined doses (P > 0.05). Conclusion: In conclusion, levosimendan might be associated with increases in sister-chromatid exchanges in cultured human lymphocytes. In vivo studies are required to confirm the present findings.

scholarly journals The Investigation of DNA Damage Induced by Adrenaline in Human Lymphocytes in Vitro/Ispitivanja Oštećenja DNK Izazvanih Adrenalinom U Limfocitima Čoveka in Vitro

2014 ◽  
Vol 64 (3) ◽  
pp. 281-292 ◽  
Author(s):  
Radaković Milena ◽  
Đelić Ninoslav ◽  
Stevanović Jevrosima ◽  
Anđelković Marko ◽  
Kolarević Stoimir ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Dna Damage ◽  
Human Lymphocytes ◽  
Reactive Oxygen ◽  
Potential Contribution ◽  
Oxygen Species ◽  
Genotoxic Effects ◽  
Isolated Human Lymphocytes ◽  
Primary Dna Damage

Abstract Adrenaline is a neurotransmitter and hormone that plays an important role in physiological regulatory mechanisms. The objective of this study was to assess primary DNA damage in isolated human lymphocytes exposed to adrenaline using the in vitro comet assay. Dose-response of human lymphocytes was determined at concentration range of adrenaline from 0.01 μM to 300 μM for various treatment times (1h, 2h, 4h and 24h). The obtained results showed that adrenaline induced DNA damage at concentration range from 5 μM to 300 μM after 1h, 2h and 4h of treatment. The slightest DNA damage was observed after 24 h of adrenaline treatment - only the highest concentrations of adrenaline (150 μM and 300 μM) caused increased level of DNA damage. In order to evaluate the potential contribution of reactive oxygen species (ROS) in adrenaline-induced DNA damage we used antioxidants catalase (100 IU/mL and 500 IU/mL) and quercetin (100 μM and 500 μM). Co-treatment of lymphocytes with adrenaline (300 μM) and antioxidants for 1 h, significantly reduced the quantity of DNA in the comet tails. Therefore, it can be concluded that adrenaline exhibits genotoxic effects mainly through induction of reactive oxygen species and that some of the DNA damage is repaired during the first four hours following the treatment with adrenaline.

scholarly journals Assessment of genotoxic effects in one-and two-cell mouse embryos in vivo and in vitro using comet assay

2020 ◽  
pp. 77-78
Author(s):  
К.Л. Плигина ◽  
А.К. Жанатаев ◽  
Е.А. Анисина ◽  
Н.О. Даугель-Дауге ◽  
А.Д. Дурнев
Keyword(s):  
Dna Damage ◽  
Comet Assay ◽  
Mitomycin C ◽  
Mouse Embryos ◽  
Methyl Methanesulfonate ◽  
Genotoxic Effects

Разработана методология оценки первичных повреждений ДНК в одно- и двухклеточных зародышах мышей методом ДНК-комет. Применимость разработанной методологии для оценки генотоксичности в зародышевых клетках in vivo и in vitro подтверждена в экспериментах с модельными генотоксикантами метилметансульфонатом, диоксидином, этопозидом и митомицином С. A methodology for evaluating DNA damage in one - and two-cell mouse embryos using the comet assay has been developed. The applicability of the developed methodology for assessing genotoxicity in vivo and in vitro was confirmed in experiments with model genotoxicants - methyl methanesulfonate, dioxidine, etoposide and mitomycin C.

Alternativas farmacéuticas: ¿pueden ser intercambiables?

2020 ◽  
Vol 2 (2) ◽  
pp. 38-42
Author(s):  
Miriam del Carmen Carrasco-Portugal ◽  
Francisco Javier Flores-Murrieta
Keyword(s):  
Generic Substitution ◽  
In Vivo Studies ◽  
Regulatory Agencies ◽  
European Medicines Agency ◽  
Reference Formulation ◽  
Active Moiety ◽  
Significant Difference ◽  
Pharmaceutical Form ◽  
Extent Of Absorption

Pharmaceutical alternatives are products with the same active moiety, but different salt, ester or pharmaceutical form. Regulatory agencies have different criteria for this kind of drug. The European Medicines Agency (EMA) accepts the generic substitution using these alternatives, whereas the Food and Drug Administration (FDA) only authorizes generic substitution of pharmaceutical equivalents. The objective of this paper is to describe some relevant aspects that should be considered before deciding on making a generic substitution with pharmaceutical alternatives. It is important to note that a pharmaceutical alternative must show no significant difference in the rate and extent of absorption (bioequivalence) in a well-conducted in vivo study when compared with the reference formulation. Current Mexican regulations state that generic substitution is possible using pharmaceutical alternatives when bioequivalence is demonstrated in in vivo studies conducted under the NOM-177-SSA1-2013 criteria. In conclusion, generic substitution with pharmaceutical alternatives is possible if these products demonstrate in vivo bioequivalence when compared with the reference product.

scholarly journals Optimizing Manufacturing and Osseointegration of Ti6Al4V Implants through Precision Casting and Calcium and Phosphorus Ion Implantation? In Vivo Results of a Large-Scale Animal Trial

Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1670 ◽  
Author(s):  
Wölfle-Roos JV ◽  
Katmer Amet B ◽  
Fiedler J ◽  
Michels H ◽  
Kappelt G ◽  
...  
Keyword(s):  
Ion Implantation ◽  
Large Scale ◽  
In Vivo Studies ◽  
Control Group ◽  
Implant Surface ◽  
Precision Casting ◽  
Pull Out ◽  
Significant Difference ◽  
Calcium And Phosphorus

Background: Uncemented implants are still associated with several major challenges, especially with regard to their manufacturing and their osseointegration. In this study, a novel manufacturing technique—an optimized form of precision casting—and a novel surface modification to promote osseointegration—calcium and phosphorus ion implantation into the implant surface—were tested in vivo. Methods: Cylindrical Ti6Al4V implants were inserted bilaterally into the tibia of 110 rats. We compared two generations of cast Ti6Al4V implants (CAST 1st GEN, n = 22, and CAST 2nd GEN, n = 22) as well as cast 2nd GEN Ti6Al4V implants with calcium (CAST + CA, n = 22) and phosphorus (CAST + P, n = 22) ion implantation to standard machined Ti6Al4V implants (control, n = 22). After 4 and 12 weeks, maximal pull-out force and bone-to-implant contact rate (BIC) were measured and compared between all five groups. Results: There was no significant difference between all five groups after 4 weeks or 12 weeks with regard to pull-out force (p > 0.05, Kruskal Wallis test). Histomorphometric analysis showed no significant difference of BIC after 4 weeks (p > 0.05, Kruskal–Wallis test), whereas there was a trend towards a higher BIC in the CAST + P group (54.8% ± 15.2%), especially compared to the control group (38.6% ± 12.8%) after 12 weeks (p = 0.053, Kruskal–Wallis test). Conclusion: In this study, we found no indication of inferiority of Ti6Al4V implants cast with the optimized centrifugal precision casting technique of the second generation compared to standard Ti6Al4V implants. As the employed manufacturing process holds considerable economic potential, mainly due to a significantly decreased material demand per implant by casting near net-shape instead of milling away most of the starting ingot, its application in manufacturing uncemented implants seems promising. However, no significant advantages of calcium or phosphorus ion implantation could be observed in this study. Due to the promising results of ion implantation in previous in vitro and in vivo studies, further in vivo studies with different ion implantation conditions should be considered.

scholarly journals A Tumbling Magnetic Microrobot System for Biomedical Applications

Micromachines ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 861
Author(s):  
Elizabeth E. Niedert ◽  
Chenghao Bi ◽  
Georges Adam ◽  
Elly Lambert ◽  
Luis Solorio ◽  
...  
Keyword(s):  
Ultrasound Imaging ◽  
Biomedical Applications ◽  
Imaging System ◽  
Ex Vivo ◽  
Negative Control ◽  
Circular Path ◽  
Rotational Axis ◽  
Significant Difference

A microrobot system comprising an untethered tumbling magnetic microrobot, a two-degree-of-freedom rotating permanent magnet, and an ultrasound imaging system has been developed for in vitro and in vivo biomedical applications. The microrobot tumbles end-over-end in a net forward motion due to applied magnetic torque from the rotating magnet. By turning the rotational axis of the magnet, two-dimensional directional control is possible and the microrobot was steered along various trajectories, including a circular path and P-shaped path. The microrobot is capable of moving over the unstructured terrain within a murine colon in in vitro, in situ, and in vivo conditions, as well as a porcine colon in ex vivo conditions. High-frequency ultrasound imaging allows for real-time determination of the microrobot’s position while it is optically occluded by animal tissue. When coated with a fluorescein payload, the microrobot was shown to release the majority of the payload over a 1-h time period in phosphate-buffered saline. Cytotoxicity tests demonstrated that the microrobot’s constituent materials, SU-8 and polydimethylsiloxane (PDMS), did not show a statistically significant difference in toxicity to murine fibroblasts from the negative control, even when the materials were doped with magnetic neodymium microparticles. The microrobot system’s capabilities make it promising for targeted drug delivery and other in vivo biomedical applications.

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