A modified suspension test for estimating the mutagenicity of samples containing free and (or) protein-bound histidine

2009 ◽  
Vol 55 (2) ◽  
pp. 146-153 ◽  
Author(s):  
Bo Liu ◽  
Jianling Jin ◽  
Yanfei Cheng ◽  
Huaiqiang Zhang ◽  
Peiji Gao
Keyword(s):  
Bone Marrow ◽  
Ames Test ◽  
Negative Control ◽  
Luria Bertani ◽  
Test Medium ◽  
Control Groups ◽  
Mutagenicity Assay ◽  
Chromosomal Aberration Test ◽  
Negative Controls ◽  
Suspension Test

The Ames test has not been very effective in estimating the mutagenicity of histidine-containing samples because external free and (or) protein-bound histidine in these samples would allow the histidine auxotrophs in such test samples to grow more compared with the negative controls that were used as the reference. This could give rise to a false positive.n this study, a modified suspension mutagenicity assay (MS assay) was deveopled. The tester strains were incubated in Luria-Bertani (LB) broth containing different concentrations of traditional Chineses medicines (TCMs) until the declining phase, and the test samples were assayed to be mutagenic or not by observing whether statistically significant differences were demonstrated in the relative reversion frequencies (RRFs) between the negative control groups and the test groups. Collectively, using LB broth as the test medium and comparing the RRFs in the declining phase made this assay less influenced by the presence of histidine in the test samples.The mutagenicity of some TCMs was measured with the MS assay. The results in MS assay were consistent with those in the mammalian bone marrow chromosomal aberration test, which indicated that the MS assay was appropriate to estimate the mutagenicity of samples containing free and (or) protein-bound histidine.

scholarly journals Genetic Toxicology and Safety Pharmacological Evaluation of Forsythin

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Zhong Han ◽  
Jianmin Guo ◽  
Feibiao Meng ◽  
Haifeng Liao ◽  
Yinghua Deng ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Ames Test ◽  
Negative Control ◽  
Fibroblast Cells ◽  
Beagle Dogs ◽  
Genetic Toxicity ◽  
Toxicological Effects ◽  
Polychromatic Erythrocytes ◽  
Significant Difference ◽  
Forsythia Suspensa

Introduction. Forsythin is the main ingredient of Forsythia suspensa and is widely used in treatment of fever, viral cold, gonorrhea, and ulcers clinically. This study aimed to evaluate the potential genetic toxicity of forsythin and its safety for human use. Methods. Based on the Good Laboratory Practice regulations and test guidelines, the genetic toxicity of forsythin was assessed by the Ames test, chromosome aberration (CA) test, and bone marrow micronucleus (MN) test in vivo. In the Ames test, five strains of Salmonella typhimurium were exposed to different concentrations of forsythin in the presence or absence of the S9 mixture, and then, the number of His + revertant colonies was counted. In the CA test, Chinese hamster lung (CHL) fibroblast cells were treated with different concentrations of forsythin, mitomycin C, or cyclophosphamide in the presence or absence of the S9 mixture, and the chromosomal aberrations were determined. In the MN test, bone marrow was isolated from the mice with different treatments, and the ratios of polychromatic erythrocytes (PCE) and erythrocytes (PCE/(PCE + NCE)) were measured. Finally, beagle dogs were divided into four groups (negative control, low dose, medium dose, and high dose groups), and then, a telemetry system was used to evaluate the safe use of forsythin. Results. Ames test results showed that the number of colonies in all test strains with different treatments showed no significantly dose-dependent increase in the presence or absence of the S9 mixture ( p > 0.05 ). In the CA test, the number of cells with aberrations in the CHL fibroblast cells treated with low, medium, and high doses of forsythin for 24/48 h in the absence of the S9 mixture was, respectively, 5.0/2.5, 4.5/1.5, and 5.0/5.0, and in the presence of the S9 mixture, the number was, respectively, 5.0, 5.0, and 4.5. These results showed that there was no significant difference compared to the negative control group either in the presence (2.0) or in the absence (4.0/2.5 for 24/48 h) of the S9 mixture ( p > 0.05 ). The MN test showed that the values of PCE/(PCE + NCE) in the negative, positive controls, and forsythin treatment groups were all more than 20%, which indicated that forsythin had no cytotoxicity. Additionally, no significant toxicological effects of forsythin on blood pressure, respiration, temperature, electrocardiogram, and other physiological indicators in the conscious beagle dogs of different groups were observed by the telemetry method. Conclusion. Our findings showed that forsythin has low probability of genetic toxicity and no significant toxicological effects, which implied that forsythin is suitable for further development and potential application.

scholarly journals The Mutagenicity and Antimutagenicity of Canarium odontophyllum (Dabai) Acetone Leaves Extracts

2017 ◽  
Vol 9 (13) ◽  
pp. 62
Author(s):  
Ahmad Rohi Ghazali ◽  
Farah Mardhiah Khairuddin ◽  
Tava Shelan Nagapan ◽  
Dayang Fredalina Basri
Keyword(s):  
Ames Test ◽  
Mutagenic Activity ◽  
Biological Activities ◽  
Negative Control ◽  
Antimutagenic Activity ◽  
Bacterial Strains ◽  
Mutagenicity Assay ◽  
Control Plate ◽  
Canarium Odontophyllum ◽  
Acetone Extracts

Canarium odontophyllum or locally known as Dabai in Sarawak is a fruit largely consumed by the locals. Based on previous studies, the plant possessed various biological activities, such as antimicrobial, antioxidant, antifungal and anticancer. Our aim was to investigate the mutagenicity and antimutagenicity of C. odontophyllum acetone leaves extracts by using the Ames test (Salmonella reverse mutagenicity assay).The Ames test also involved the pre-incubation method against Salmonella typhimurium TA98 and TA100 bacterial strains in the absence and presence of metabolic activator S9 system. C. odontophyllum crude acetone extracts were diluted with 10% DMSO to obtain three different concentrations of 3.125, 12.5 and 50 mg/ml. To determine the mutagenicity effects of the extracts, each concentration of the extract was evaluated based on the two-fold value of the number of revertant’s colony in negative control plate as the cut-of point. No mutagenic activity was observed for the frameshift mutation (TA98) and base-pair substitution mutation (TA100) in all concentrations of C. odontophyllum in the presence and absence of metabolic activator S9 system. Antimutagenicity test was carried out to determine the potential of C. odontophyllum extracts to inhibit the mutation induced by specific mutagens. The highest antimutagenic activity was seen in the presence of metabolic activator S9 system with inhibition percentage greater than 50% in both bacteria strains TA98 (62.38%) and TA100 (58.24%). In conclusion, C. odontophyllum acetone leaves extract was not mutagenic and had significant inhibitory effects on mutagenicity in both bacterial strains with and without the metabolic activator S9 system. Our results could contribute to the safe use of C. odontophyllum. In addition, based on the significant antimutagenic activity demonstrated by the C. odontophyllum acetone leaves extracts, the extract could also be developed as a chemopreventive agent.

Teratogenicity Assessment of Dental Implants

2012 ◽  
Vol 630 ◽  
pp. 420-424
Author(s):  
Jian Liu ◽  
Yang Yang ◽  
Fen Ju Liu ◽  
Qing Fang Liu
Keyword(s):  
Bone Marrow ◽  
Dental Implant ◽  
Ames Test ◽  
Bone Marrow Cells ◽  
Micronucleus Test ◽  
Mutagenic Effect ◽  
Control Groups ◽  
Medical Products ◽  
Activation Conditions ◽  
Chromosome Aberration Test

To evaluate the teratogenicity of the dental implant and provide a basis for safe applications of medical products. Chromosome aberration test, micronucleus test and the Ames test of the dental implant samples were performed. The results showed that samples of the dental implant did not cause chromosomal aberrations, nor induced the increase of bone marrow cells micronucleus incidence; Compared with the control groups, the number of revertant colonies did not increase significantly in the dental implant extracts and 1/5, 1/25 diluted groups, both under the activation and non-activation conditions, suggesting that no mutagenic effect was caused by the dental implant samples. All of the results indicated that the dental implant could not induce any teratogenic toxicity or carcinogenic and toxicity, so the dental implant can be safely used in clinical practice.

scholarly journals Effectiveness of Casein Phosphopeptide-Amorphous Calcium Phosphate (CPP-ACP) Compared to Fluoride Products in an In-Vitro Demineralization Model

Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 5974
Author(s):  
Markus Reise ◽  
Stefan Kranz ◽  
Markus Heyder ◽  
Klaus D. Jandt ◽  
Bernd W. Sigusch
Keyword(s):  
Calcium Phosphate ◽  
Amorphous Calcium Phosphate ◽  
Polarized Light ◽  
Positive Control ◽  
Negative Control ◽  
Control Groups ◽  
Casein Phosphopeptide ◽  
Tooth Mousse ◽  
Negative Controls

The goal of this study was to evaluate the effectiveness of the toothpaste Tooth Mousse compared to conventional fluoride-based versions in the prevention of enamel and dentin demineralization. Human enamel and dentin samples (n = 120 each) were exposed to artificial demineralization at pH 4.92. During the demineralization process, the samples in the test groups were periodically treated with Tooth Mousse (TM) containing casein-phosphopeptide -amorphous-calcium-phosphate (CPP-ACP) and Tooth Mousse Plus (TMP) containing amorphous-calcium-fluoride-phosphate (CPP-ACPF) to evaluate their protective properties. Fluoride toothpastes containing 1400 ppm amine fluoride (AmF) and 1450 ppm sodium fluoride (NaF) were applied in the positive control groups. Treatment with distilled water (group C-W) or demineralization without treatment (group C-D) served as negative controls. After the demineralization and treatment process, all samples were cut longitudinally and lesion depths were determined at six locations using polarized light microscopy. In TM/TMP groups (enamel: 80/86 µm, dentin: 153/156 µm) lesion depths were significantly smaller compared to the negative control groups C-W/C-D (enamel: 99/111 µm, dentin: 163/166 µm). However, TM and TMP compared to the positive controls AmF/NaF (enamel: 58/63 µm, dentin: 87/109 µm) showed higher lesion depths. The application of TM/TMP (89%/78%) during demineralization led to a reduced number of severe lesions compared to the negative controls C-W/C-D (100%/95%). In this study we demonstrate that Tooth Mousse is less effective regarding prevention of enamel and dentin demineralization compared to fluoride containing toothpastes.

Antimutagenic, Antigenotoxic, and Anticytotoxic Activities of Silybum Marianum [L.] Gaertn Assessed by the Salmonella Mutagenicity Assay (Ames Test) and the Micronucleus Test in Mice Bone Marrow

2016 ◽  
Vol 68 (5) ◽  
pp. 848-855 ◽  
Author(s):  
Flávio Fernandes Veloso Borges ◽  
Carolina Ribeiroe Silva ◽  
Jefferson Hollanda Véras ◽  
Clever Gomes Cardoso ◽  
Aparecido Divino da Cruz ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Ames Test ◽  
Micronucleus Test ◽  
Silybum Marianum ◽  
Mutagenicity Assay

scholarly journals Effect of sage (Salvia officinalis) aqueous extract on mitotic index in albino male mice

2010 ◽  
Vol 4 (1) ◽  
pp. 36-43
Author(s):  
Roqaya, M. Al-Ezzy ◽  
Khulood Al-Samarrae ◽  
Ali H. Ad'haih
Keyword(s):  
Bone Marrow ◽  
Mitotic Index ◽  
Aqueous Extract ◽  
Bone Marrow Cells ◽  
Negative Control ◽  
Salvia Officinalis ◽  
Male Mice ◽  
Negative Controls ◽  
The Ideal ◽  
Marrow Cells

This study aimed to evaluate the effect of aqueous extract of sage (Salvia officinalis) on bone marrow cells in albino male mice by using three doses ( 83.9, 167.8 or 251.7 mg/kg) and cytosar drug at dose of ( 1.54 mg/kg). The results showed that sage has the ability to increase the mitotic index in mice in comparing with the negative control and in mice treated with cytosar drug that caused reduction in mitotic index. The results of pre- and post-treatment with the ideal dose of aqueous extract of sage and cytosar drug showed the ability of sage to increase the mitotic index of bone marrow cells in mice in comparing with the negative controls.

scholarly journals Evaluation of ionic degradation and slot corrosion of metallic brackets by the action of different dentifrices

2013 ◽  
Vol 18 (1) ◽  
pp. 86-93
Author(s):  
Gustavo Antônio Martins Brandão ◽  
Rafael Menezes Simas ◽  
Leandro Moreira de Almeida ◽  
Juliana Melo da Silva ◽  
Marcelo de Castro Meneghim ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Artificial Saliva ◽  
Positive Control ◽  
Negative Control ◽  
Sem Analysis ◽  
Wilcoxon Test ◽  
Surface Polishing ◽  
Aluminium Ion ◽  
Negative Controls

OBJECTIVE: To evaluate the in vitro ionic degradation and slot base corrosion of metallic brackets subjected to brushing with dentifrices, through analysis of chemical composition by Energy Dispersive Spectroscopy (EDS) and qualitative analysis by Scanning Electron Microscopy (SEM). METHODS: Thirty eight brackets were selected and randomly divided into four experimental groups (n = 7). Two groups (n = 5) worked as positive and negative controls. Simulated orthodontic braces were assembled using 0.019 x 0.025-in stainless steel wires and elastomeric rings. The groups were divided according to surface treatment: G1 (Máxima Proteção Anticáries®); G2 (Total 12®); G3 (Sensitive®); G4 (Branqueador®); Positive control (artificial saliva) and Negative control (no treatment). Twenty eight brushing cycles were performed and evaluations were made before (T0) and after (T1) experiment. RESULTS: The Wilcoxon test showed no difference in ionic concentrations of titanium (Ti), chromium (Cr), iron (Fe) and nickel (Ni) between groups. G2 presented significant reduction (p < 0.05) in the concentration of aluminium ion (Al). Groups G3 and G4 presented significant increase (p < 0.05) in the concentration of aluminium ion. The SEM analysis showed increased characteristics indicative of corrosion on groups G2, G3 and G4. CONCLUSION: The EDS analysis revealed that control groups and G1 did not suffer alterations on the chemical composition. G2 presented degradation in the amount of Al ion. G3 and G4 suffered increase in the concentration of Al. The immersion in artificial saliva and the dentifrice Máxima Proteção Anticáries® did not alter the surface polishing. The dentifrices Total 12®, Sensitive® and Branqueador® altered the surface polishing.

scholarly journals Silencing long non-coding RNA ROR improves sensitivity of non-small-cell lung cancer to cisplatin resistance by inhibiting PI3K/Akt/mTOR signaling pathway

Tumor Biology ◽  
2017 ◽  
Vol 39 (5) ◽  
pp. 101042831769756 ◽  
Author(s):  
Hui Shi ◽  
Jin Pu ◽  
Xiao-Li Zhou ◽  
Yun-Ye Ning ◽  
Chong Bai
Keyword(s):  
Cell Proliferation ◽  
Signaling Pathway ◽  
Negative Control ◽  
Mtor Signaling ◽  
Mtor Signaling Pathway ◽  
Control Groups ◽  
Over Expression ◽  
Non Coding Rna ◽  
Protein Expressions ◽  
Long Non Coding Rna

This study aimed to investigate the effects of long non-coding RNA ROR (regulator of reprogramming) on cisplatin (DDP) resistance in patients with non-small-cell lung cancer by regulating PI3K/Akt/mTOR signaling pathway. Human cisplatin-resistant A549/DDP cell lines were selected and divided into control group, negative control group, si-ROR group, ROR over-expression group, Wortmannin group, and ROR over-expression + Wortmannin group. MTT assay was used to determine the optimum inhibitory concentration of DDP. Quantitative real-time polymerase chain reaction and western blotting were applied to detect expressions of long non-coding RNA ROR, PI3K, Akt, and mTOR. Colony-forming assay, scratch test, Transwell assay, and flow cytometry were conducted to detect cell proliferation, migration, invasion, and apoptosis, respectively. Tumor-formation assay was performed to detect the growth of transplanted tumors. Long non-coding RNA ROR expression was high in human A549/DDP cell lines. Compared with the control and negative control groups, the mRNA and protein expressions of PI3K, Akt, mTOR, and bcl-2 decreased, whereas the mRNA and protein expression of bax and the sensitivity of cells to DDP significantly increased. Cell proliferation, migration, and invasion abilities decreased in the si-ROR and Wortmannin groups. In comparison with control and negative control groups, the mRNA and protein expressions of PI3K, Akt, mTOR, and bcl-2 increased, whereas the mRNA and protein expressions of bax decreased, the sensitivity of cells to DDP significantly increased, and cell proliferation, migration, and invasion abilities decreased in the ROR over-expression group. For nude mice in tumor-formation assay, compared with control and negative control groups, the tumor weight was found to be lighter (1.03 ± 0.15) g, the protein expressions of PI3K, Akt, mTOR, and bcl-2 decreased, and the protein expression of bax increased in the si-ROR group. Long non-coding RNA ROR may affect the sensitivity of lung adenocarcinoma cells to DDP by targeting PI3K/Akt/mTOR signaling pathway.

slowly growing natural populations. Various approaches have been adopted in order to improve the sensitivity. These have included the use of multiple probes labelled with a single fluor (Lee et al. 1993); or labelled with multiple fluors (Trebesius et al. 1994) and enzyme-linked probes or detection systems that allow signal amplification (Lebaron et al. 1997, Schonhuber et al. 1999). The latter indirect approach not only has the potential for signal amplification, but may also be used in natural samples showing high levels of autofluorescence. Any thorough identification method has to include positive and negative controls. False-positive results may either be caused by cells emitting autofluorescence upon excitation or by nonspecific binding of the probe to nontarget cells. Samples should therefore be checked for autofluorescence before hybridization and a negative control with a fluorescent oligonucleotide not complementary to rRNA has to be applied to check for sequence-independent nonspecific binding. Such non-specific binding may be due to interaction of the dye compound of the probe with hydrophobic cell components. Failures to detect cells containing target sequences (false-negatives) may originate from cells with either low cellular ribosome content or limited permeability of the cell periphery for the fluorescent probe (Manz et al. 1992). With the rapidly expanding database of 16S rRNA sequences, the problem of probe specificity has become more apparent and the design of probes is becoming increasingly difficult. These problems are also applicable to PCR and other oligonucleotide-dependent techniques. The problem of probe specificity may be overcome by using multiple specific oligonucleotide probes targeting different sites on the rRNA molecule and labelled with different fluorochromes. While a single oligonucleotide target sequence may be found in a number of related taxa, the probability that target sites for three designed oligonucleotides are found in a nontarget organism is, however, much reduced.

2003 ◽  
pp. 232-232
Keyword(s):  
Signal Amplification ◽  
Specific Binding ◽  
Natural Populations ◽  
Negative Control ◽  
Target Sequence ◽  
Cell Periphery ◽  
Nonspecific Binding ◽  
Detection Systems ◽  
Cell Components ◽  
Negative Controls
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