Evaluation of the genotoxicity, cytotoxicity, and bioactivity of calcium silicate-based cements.

BACKGROUND: As calcium silicate-based cements (CSCs) have found success in various vital pulp therapy applications, several new CSC products have emerged. This study aimed to assess the genotoxicity, cytotoxicity, and bioactivity of four CSCs by comparing the newly introduced materials Bio MTA+ and MTA Cem with previously studied materials, Biodentine and NeoMTA. METHODS: Genotoxicity was evaluated using the micronucleus (MN) assay in human peripheral blood lymphocyte cells, measuring MN frequency and nuclear division index (NDI). Cytotoxicity was assessed in human dental pulp stem cells through the Water-Soluble Tetrazolium Salt-1 (WST-1) colorimetric assay. Bioactivity was determined by ELISA, measuring the levels of angiogenic and odontogenic markers (BMP-2, FGF-2, VEGF, and ALP). Statistical analyses included ANOVA, Dunnet and Sidak tests, and Wald chi-square test. (p < .05). RESULTS: The MN frequency in the groups was significantly lower than that in the positive control group (tetraconazole) (p < .05). NDI values decreased with increasing concentration (p < .05). Bio MTA+ and NeoMTA showed decreased cell viability at all concentrations in 7-day cultures (p < .01). All materials increased BMP-2, FGF-2, and VEGF levels, with Biodentine and NeoMTA showing the highest levels of BMP-2 and FGF-2 on day 7. Biodentine displayed the highest VEGF levels on day 7. Biodentine and NeoMTA groups exhibited significantly higher ALP activity than the Bio MTA+ and MTA Cem groups by day 7. CONCLUSION: Bio MTA+ and MTA Cem demonstrated no genotoxic or cytotoxic effects. Moreover, this study revealed bioactive potentials of Bio MTA+ and MTA Cem by enhancing the expression of angiogenic and osteogenic growth factors.

Robotic approach to the reduction of dental anxiety in children.

OBJECTIVE: We introduced a humanoid robot for the use of techno-psychological distraction techniques in children aged 4-10 to reduce their anxiety and improve their behaviour during dental treatment. MATERIALS AND METHODS: Two hundred children (98 boys, 102 girls; mean age: 6.5 ± 1.66 years) appointed for first time for dental caries were included and randomly divided into two groups [N = 100 for each group; RG: Robot Group (accompanied by the robot), CG: Control Group (without robot accompaniment)]. Half of the children were treated under local anaesthesia (infiltration anaesthesia) (n = 50 within each group) and half of the children were treated without any local anaesthesia (n = 50 within each group) within each group. The success rate of the new robotic distraction technique was evaluated by using Parental Corah Dental Anxiety Scale, Facial Image Scale (FIS), physiological pulse rate and Frankl Behaviour Rating Scale (FBRS). RESULT: Pulse rates, which measured during treatment and after treatment, were statistically higher in CG than in RG (p < .05). After dental treatment, the FIS score was significantly higher in CG than RG (p < .05). 88.3% of the children in RG stated that they wanted the robot to be with them at the next treatment session. CONCLUSIONS: Robotic technology can successfully help in coping with dental anxiety and stress, and helps children to behave better in dental office.

Ammonium nitrate and iron nutrition effects on some nitrogen assimilation enzymes and metabolites in Spirulina platensis.

The effect of various concentrations of ammonium nitrate (5-60 mM), an economical nitrogen source, on the growth, nitrate-ammonium uptake rates, production of some pigments and metabolites, and some nitrogen assimilation enzymes such as nitrate reductase (NR), nitrite reductase (NiR), glutamine synthetase (GS), and glutamate synthase (GOGAT) in Spirulina platensis (Gamont) Geitler was investigated. Ten millimolars of ammonium nitrate stimulated the growth, production of pigments and the other metabolites, and enzyme activities, whereas 30 and 60 mM ammonium nitrate caused inhibition. In the presence of 10 mM ammonium nitrate, different concentrations of iron were tried in the growth media of S. platensis. After achieving the best growth, levels of metabolite and pigment production, and enzyme activities in the presence of 10 mM ammonium nitrate as a nitrogen source, different iron concentrations (10-100 µM) were tried in the growth medium of S. platensis. The highest growth, pigment and metabolite levels, and enzyme activities were determined in the medium containing 50 µM iron and 10 mM ammonium nitrate. In this optimum condition, the highest dry biomass level, chlorophyll a, and pyruvate contents were obtained as 55.42 ± 3.8 mg mL(-1) , 93.114 ± 7.9 µg g(-1) , and 212.5 ± 18.7 µg g(-1) , respectively. The highest NR, NiR, GS, and GOGAT activities were 67.16 ± 5.1, 777.92 ± 52, 0.141 ± 0.01, and 44.45 ± 3.6, respectively. Additionally, 10 mM ammonium nitrate is an economical and efficient nitrogen source for nitrogen assimilation of S. platensis, and 50 µM iron is optimum for the growth of S. platensis.

Synergistic Growth Inhibitory Effects of Eryngium kotschyi Extracts with Conventional Cytotoxic Agents: Cisplatin and Doxorubicin against Human Endometrium Cancer Cells.

BACKGROUND: Endometrial cancer is one of the most common types of cancer. For this reason, various studies have been carried out on its treatment and the effects of natural products on this disease. OBJECTIVES: This study aimed to examine the growth inhibitory effects of Eryngium kotschyi Boiss. ethyl acetate [EKE] and butanol [EKB] obtained from the main methanol [EKM] extract from the aerial parts on human endometrium carcinoma [RL95-2] cells and their synergistic effect with cisplatin or doxorubicin. METHODS: RL95-2 cells were treated with E. kotschyi extracts either alone or in combination with cisplatin or doxorubicin. The effects on cell growth were determined using the MTT assay and real-time cell analysis xCELLigence. RESULTS: The extracts demonstrated growth inhibitory activity, with a certain degree of selectivity against the RL95-2 cell line. Synergistic effects of EKE/cisplatin or doxorubicin at different concentration levels were demonstrated in RL95-2 cells. In some instances, the EKE/doxorubicin combinations resulted in antagonistic effects. The reduction level of cell viability was different and specific to each combination for the RL95-2 cell line. CONCLUSION: The growth inhibitory activity of cisplatin or doxorubicin, as a single agent, may be modified by combinations of the extracts and be synergistically enhanced in some cases. A significant synergistic effect of EKE on the RL95-2 cell line with cisplatin and doxorubicin was observed. This cytotoxic effect can be investigated in terms of molecular mechanisms. This study is the first of its kind in the literature. The mechanisms involved in this interaction between chemotherapeutic drugs and plant extracts remain unclear and should be further evaluated.