Biomonitoring of Oxidative-Stress-Related Genotoxic Damage in Patients with End-Stage Renal Disease.

Chronic kidney disease (CKD), a common progressive renal failure characterized by the permanent loss of functional nephrons can rapidly progress to end-stage renal disease, which is known to be an irreversible renal failure. In the therapy of ESRD, there are controversial suggestions about the use of regular dialysis, since it is claimed to increase oxidative stress, which may increase mortality in patients. In ESRD, oxidative-stress-related DNA damage is expected to occur, along with increased inflammation. Many factors, including heavy metals, have been suggested to exacerbate the damage in kidneys; therefore, it is important to reveal the relationship between these factors in ESRD patients. There are very few studies showing the role of oxidative-stress-related genotoxic events in the progression of ESRD patients. Within the scope of this study, genotoxic damage was evaluated using the comet assay and 8-OHdG measurement in patients with ESRD who were undergoing hemodialysis. The biochemical changes, the levels of heavy metals (aluminum, arsenic, cadmium, lead, and mercury) in the blood, and the oxidative biomarkers, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and malondialdehyde (MDA) levels were evaluated, and their relationship with genotoxic damages was revealed. Genotoxicity, oxidative stress, and heavy-metal levels, except mercury, increased significantly in all renal patients. DNA damage, 8OHdG, and MDA significantly increased, and GSH significantly decreased in patients undergoing dialysis, compared with those not having dialysis. The duration and the severity of disease was positively correlated with increased aluminum levels and moderate positively correlated with increased DNA damage and cadmium levels. In conclusion, this study revealed that the oxidative-stress-related DNA damage, and also the levels of Al and Cd, increased in ESRD patients. It is assumed that these changes may play an important role in the progression of renal damage. Approaches for reducing oxidative-stress-related DNA damage and heavy-metal load in ESRD patients are recommended.

Efficacy of preheated chelating agents on calcium ion removal from instrumented root canals.

BACKGROUND: The heating of chelating agents such as EDTA increases dentin wettability by decreasing surface tension. However, the calcium ion release effect of preheated chelating agents in instrumented root canals has not yet been mentioned. In this study, it was aimed to evaluate the number of calcium ions removed by the pre-heated chelating agents from the root canals. MATERIAL AND METHODS: After 51 bovine teeth were instrumented, three of them were separated as negative controls and the remaining teeth were divided into six groups according to the temperature of the solution (at 22 or 37ºC): EDTA-22, CITRIC-22, QMix-22, EDTA-37, CITRIC-37 and QMix-37. Following irrigation, calcium ion levels were determined by atomic absorption spectrophotometer in chelating agents collected from the root canals. RESULTS: QMix solution eliminated significantly more calcium ions than other chelating agents at different temperatures (p< 0.05). Regardless of the heating, QMix and 17% EDTA were significantly superior to 40% Citric acid (p< 0.05) while no significant difference was detected between QMix and 17% EDTA groups (p< 0.05). Heating all chelating agents did not significantly increase their ability to remove calcium ions from pre-instrumented root canals (P< 0.05). In the SEM examination, it was observed that the smear layer was removed from the middle third of the roots, except for the negative control group. CONCLUSIONS: Temperature changes have shown that these agents do not increase the ability of the smear layer to dissolve the inorganic structure. QMix at different temperatures may be recommended to use as the final chelating agent. Key words:EDTA, citric acid, QMix, calcium ions, temperature.

Plasma prolidase levels are high in schizophrenia but not in first-episode psychosis.

An increasing number of studies have focussed on the neurobiology of schizophrenia (SCH), contributing to a better understanding of this disorder. Prolidase is a metalloprotease found in various tissues, which has been associated with the concentrations of proline, a neurotransmitter, in the brain. There is evidence to suggest that elevated proline levels play a role in SCH. The aim of the present study was to compare plasma proline levels in patients with drug-naive first-episode psychosis (FEP) and in those with SCH. Patients diagnosed with FEP (n = 26) and SCH (n = 26) were recruited for this study, in addition to healthy control volunteers (n = 26). Plasma prolidase levels were found to be elevated in the SCH group compared to drug-naive FEP and healthy control groups. This finding indicates that prolidase levels are higher in SCH patients, while levels in patients with drug-naive FEP are similar to those of healthy control. Follow-up studies are needed to provide a better understanding of prolidase in the etiopathogenesis of SCH.

Investigation of water sorption and aluminum releases from high viscosity and resin modified glass ionomer.

BACKGROUND: High viscosity glass ionomer cement (HVGIC) and resin-modified glass ionomer cement (RMGIC) have recently been clinically preferred thanks to their numerous advantages. However, initial moisture contamination has a negative effect on the mechanical and physical properties of these cements. The aim of this study was in vitro of HVGICs and RMGICs, with and without surface protection, on water sorption, solubility and release of aluminum. MATERIAL AND METHODS: In this study, as HVGICs; Equia Forte, IonoStar Plus, Riva Self Cure; as RMCIS, Ionolux and Riva Light Cure; and as control, Z250 universal composite was used. Equia coat, Voco varnish and Riva coat were chosen as surface protective. Water sorption and solubility levels of the samples were measured according to ISO 4049:2009. Al levels released from samples were determined by graphite furnace atomic absorption spectroscopy (GFAAS) for 7, 14 and 21 days. Statistical evaluation of the results was made using one-way variance analysis (ANOVA) and Tukey post-hoc test (p<0.05). RESULTS: RMGICs from restorative materials showed more water absorption than HVGICs, but no differences in solubility. Among the materials tested, the water absorption values of the HVGIC and RMGIC materials without surface protection were higher than those with the surface protection (p<0.001). CONCLUSIONS: It was determined that the Al release of HVGIC and RMGIC groups with the surface protection were lower in all time periods than the groups without surface protection (p<0.001). The application of surface protection effectively reduced water sorption and Al release from HVGICs and RMGICs. Key words:Highly viscous glass ionomer cement, resin coating, aluminum release, water sorption, solubility.

Evaluation of a novel oxiconazole nitrate formulation: The thermosensitive gel.

Superficial fungal infections caused by Candida species are common skin diseases. Therefore, this study aimed to develop a new formulation containing oxiconazole nitrate, which is an azole group derivative for antifungal treatment, as a thermosensitive gel since there has been no literature study until now. MIC value of the novel thermosensitive formulation against three Candida species was calculated and time-dependent antifungal activity analysis was performed. Viscosity, transition temperature Tsol-gel (°C) and gelation time of the thermosensitive gel formulation were also determined in the viscometer. The measurements performed on the tensilometer device were analyzed for adhesion hardness and elongation percentages of the formulation. In the FT-IR spectrometer, the spectrum of solution and gel state was compared between 650 and 4000 cm-1 and it was found that there is no difference between them. It was found that the temperature is reversible on the formulation and did not cause any disruption of its components. Characterization parameters of the thermosensitive gel formulation containing oxiconazole nitrate and time-dependent activity against Candida species was observed to be the same as those of the solution containing only oxiconazole nitrate. MIC, MFC and time-dependent antifungal analysis did not show any particular difference between formulation and oxiconazole nitrate itself. Thermosensitive gel formulation containing oxiconazole nitrate was found to be effective on superficial fungal infections. We believe it is also appropriate for in vivo usage, but it is necessary to perform animal and human research. It is also needed to evaluate the formulation against other etiologic agents of superficial fungal infections.

In vivo evaluation of the effects of hydraulic calcium silicate dental cements on plasma and liver aluminium levels in rats.

Our aim was to test whether the presence of three hydraulic calcium silicate dental cements--MTA Angelus, MTA Fillapex, and Theracal LC--in the dental extraction socket of an in vivo model, would affect the levels of aluminium (Al) in the plasma and liver. Following anesthesia, the right upper incisor of each male Wistar albino rat was extracted and polyethylene tubes filled with MTA Angelus, MTA Fillapex, or Theracal LC were inserted into the depth of the extraction socket and gingival tissue was sutured. The rats were killed 7, 30, or 60 d after the operation. Blood and liver samples were obtained from the rats before they were killed, and the levels of Al were measured by atomic absorption spectrometry. Plasma Al levels were higher in the rats in which the mineral trioxide aggregate (MTA) cements were implanted, especially MTA Angelus and MTA Fillapex, compared with control rats. In liver samples, however, the differences in Al level were not statistically significant. Our results show that Al might have been released into the circulation from the three dental cements tested, especially MTA Angelus and MTA Fillapex. Further research should be carried out on the possible biological effects of Al liberated from dental cements.