Effects of Intracanal Curcumin and Aloe vera on pH Changes in Simulated Root Surface Resorption Defects: An In vitro Study

Introduction: Commonly used medicaments in the treatment of external inflammatory root resorption (EIRR) have shown adverse effects; resulting in an increasing tendency to employ natural and/or herbal medication. The present in vitro study aimed to evaluate the effects of curcumin and aloe vera, as two natural medicaments, on the changes of pH in external root surface defects; and compare their outcomes with the results obtained from the application of calcium hydroxide, as a conventional medicament used in endodontic treatments. Materials and Methods: In the current investigation, 92 permanent teeth, with a single root canal, were randomly divided into four groups. Similar cavities were created on the buccal surfaces of roots, 5 mm from their apices. The root canals in each of the study groups were filled with curcumin, aloe vera, calcium hydroxide or normal saline. The pH was measured after 20 min (i.e. the baseline), 1, 7, 14, 21, and 28 days using a digital pH meter. The data were analysed using repeated-measures ANOVA and the statistical significance was set at P<0.05. Results: At the baseline, day 1 and day 7, the mean pH of both curcumin and aloe vera groups was higher than the mean pH of calcium hydroxide and normal saline groups (P<0.05). On day 14, the mean pH of aloe vera group was higher than that of calcium hydroxide and normal saline groups (P<0.05). On days 21 and 28, the mean pH of aloe vera group was higher than the mean pH of all the other groups (P<0.05). All other intergroup differences were not statistically significant at each time point (P>0.05). Conclusion: The current in vitro study demonstrated that aloe vera was more alkaline than curcumin; nevertheless, both groups exhibited more alkalinity than calcium hydroxide

Dietary conjugated linoleic acid (CLA) and lecithin affects levels of serum cholesterol, triglyceride, lipoprotein and hypoxic stress resistance in rainbow trout (Oncorhynchus mykiss)

Considering the role of conjugated linoleic acid (CLA) and soybean lecithin (SBL) in fat digestion, absorption and metabolism as well as stress resistance in aquatic organisms, the current study was a 74-day attempt to investigate the synergistic effects of these two compounds on stress resistance and blood lipoprotein levels of rainbow trout (Oncorhynchus mykiss) weighing 120±5 g. Nine isonitrogenous and isocaloric experimental diets containing 1, 2 and 3% CLA and 2, 3 and 4% soybean lecithin on the basis of the basal control diet (free from CLA and lecithin) were formulated. The fish were exposed to three ascending periods of hypoxic stress (7.5, 15 and 30 min) at the end of culture period. The dissolved oxygen was decreased to 1.96 ppm by injecting nitrogen gas. Significantly higher levels of cortisol and glucose were detected in fish fed on diets having higher levels of SBL (2%) and CLA (3%) at higher stress time improving the resistance to hypoxia stress (P≤0.05). Moreover, levels of triglyceride (TRG), cholesterol (COL), low density lipoprotein (LDL), very low-density lipoprotein (VLDL) and high density lipoprotein (HDL) also increased significantly compared to the control group (P≤0.05). This study reveals that using 2% SBL and 3% CLA in rainbow trout feed can promote resistance to hypoxic stress

Fluid-structure interaction of blood flow around a vein valve

Introduction: Venous valves are a type of one-way valves which conduct blood flow toward the heart and prevent its backflow. Any malfunction of these organs may cause serious problems in the circulatory system. Numerical simulation can give us detailed information and point to point data such as velocity, wall shear stress, and von Mises stress from veins with small diameters, as obtaining such data is almost impossible using current medical devices. Having detailed information about fluid flow and valves' function can help the treatment of the related diseases. Methods: In the present work, the blood flow through a venous valve considering the flexibility of the vein wall and valve leaflets is investigated numerically. The governing equations of fluid flow and solid domain are discretized and solved by the Galerkin finite element method. Results: The obtained results showed that the blood velocity increases from inlet to the leaflets and then decreases passing behind the valve. A pair of vortices and the trapped region was observed just behind the valves. These regions have low shear stresses and are capable of sediment formation. Conclusion: The von Mises stress which is a criterion for the breakdown of solid materials was obtained. It was also observed that a maximum value occurred at the bottom of the leaflets

Thermo-hydraulic performance optimization of a disk-shaped microchannel heat sink applying computational fluid dynamics, artificial neural network, and response surface methodology

The current research focuses on optimizing the Nusselt number (Nu) and pressure drop (ΔP) in a bionic fractal heat sink. The artificial neural network (ANN) and response surface methodology (RSM) were used to model the thermos-hydraulic behavior of the MCHS. The aspect ratios of t/b (cavities' upper side to bottom side ratio) and h/b (cavities’ height to bottom side ratio), as well as the Reynolds number, were set as the independent variables in both ANN and RSM models. After finding the optimum state for the copper-made MCHS (containing the optimum design of the cavities along with the best applied velocity), different materials were tested and compared with the base case (heat sink made of copper). The obtained results indicated that both ANN and RSM models (with determination coefficient of 99.9 %) could exactly anticipate heat transfer and ΔP to a large extent. To achieve the optimal design of the microchannel heat sink (MCHS) with the objective of maximizing Nu and minimizing ΔP, the efficiency index of the device was evaluated. The analysis revealed that the highest efficiency index (1.070 by RSM and 1.067 by ANN methods) was attained when the aspect ratios were t/b = 0.2, h/b = 0.2, and the Reynolds number was 1000. Next, the effect of the different materials on heat sink performance was investigated, and it was observed that by reducing the thermal conductivity, the thermal resistance of the heat sink increased and its overall performance decreased

Numerical Investigation of Solar Collectors as A Potential Source for Sintering of ZrB2

Sintering of ceramics is an energy-consuming process that needs high temperatures, therefore, in the present work; solar energy is used to produce high temperatures for the sintering aim of different materials. Solar energy concentrators increase the intensity of incident energy to the receiver provides high temperatures. Ultrahigh-temperature ceramics (UHTCs) due to their high melting point can also be a good alternative for receiver materials. In the present work, ZrB2 is introduced as an alternative material for solar receivers which can withstand high temperatures of sintering. The governing equations, including heat radiation and conduction ones are solved numerically using the finite element method. Transient heat transfer in the concentrator-collector system is investigated to check the feasibility of high temperatures needs for sintering at the receiver. The highest temperature of 1680 °C was achieved after 15 minutes at the focal point of the concentrator when the solar heat flux of 6.86 w/mm2 used for the location of the city of Ardabil in Iran. The obtained temperature can be used to sintering of some groups of materials

The effect of endurance training combined with adenosine on the gene expression of UCP-1 and MAPK p38 in subcutaneous adipose tissue of male Wistar rats fed a high -fat diet

Background: Strategies to increase energy expenditure are an attractive approach to reduce excess fat storage and body weight to improve metabolic health. The aim of the present study was to investigate the effects of endurance training combined with adenosine injection on the gene expression of UCP-1 and MAPK p38 in the subcutaneous adipose tissue of male rats fed a high-fat diet. Materials and Methods: Forty rats were randomly divided into 4 groups: 1. normal control, 2. high-fat diet (HFD) control, 3. HFD + adenosine, and 4. HFD + endurance training + adenosine. After 13 weeks of HFD, 12 weeks of endurance training on a moderate-intensity treadmill was performed. UCP-1 and MAPK p38 mRNA levels were measured by RT-PCR. Results: A significant increase in UCP-1 was observed with in HFD + endurance training + adenosine and HFD + adenosine compared to normal and HFD controls. A significant decrease in MAPK p38 was also observed with HFD + endurance training + adenosine and HFD + adenosine compared to HFD. Conclusion: Endurance training and adenosine are likely activators of UCP-1 gene expression and can be used as effective lipolytic agents in obesity. The MAPK p38 pathway increases glucose uptake by insulin and also induces oxidative phosphorylation in mitochondria following a healthy diet and aerobic activity

Evaluation of heavy metal content of some lipsticks in Iran market

This study quantitatively estimated heavy metals as cadmium, lead, chromium and nickel (Cd, Pb, Cr and Ni) using flame atomic absorption spectrometry (FAAS) in ten lipstick products sold by local markets in Sari, Mazandaran State, Iran. All the samples were digested in HNO3 and HClO4 and then evaluated for heavy metal contents. All the concentrations are mean value of triplicate experiments for each sample. Analysis of variance (ANOVA) and Tukey post-hoc tests were used to determine significant variations in heavy metal contents and p < 0.05 was considered as significant. The determined range of cadmium, lead, chromium and nickel were 0.01-0.05&nbsp; g /g, 0.18-0.80&nbsp; g/g, 0.06-0.75 g/g, and 0.00-0.34 g/g, respectively. These results showed that nickel and cadmium contents were less than WHO and US FDA safe limit, while for chromium only one samples (No. 5) showed higher concentration than safe limit. The content of lead in all samples were lower than safe limit unless sample 6 which showed high level of lead