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Statement of the Problem: Many efforts have been made to improve the properties of mineral trioxide aggregate (MTA), including the incorporation of nanoparticles. Purpose: The aim of this study was to investigate the incorporation of zinc oxide and hydroxyapatite nanoparticles on the compressive strength of white MTA (WMTA). Materials and Method: In this in vitro study, the following materials were evaluated: MTA, MTA+5% zinc oxide (ZnO) nanoparticles, MTA+10% zinc oxide nanoparticles, MTA+5% hydroxyapatite (HA) nanoparticles, MTA+10% zinc oxide nanoparticles. The compressive strength of the groups under investigation was measured on days 4 and 21 after mixing the MTA using a universal testing machine. Two-way ANOVA test was used to compare the groups and determine the significance of the effect of time and material on the compressive strength (p <0.05). Results: The highest and lowest compressive strength values were respectively measured for the second group, MTA/21 days, and the fourth group, MTA+Nano ZnO/4 days. Two-way ANOVA indicated that incorporation of zinc oxide and hydroxyapatite nanoparticles into MTA did not have a significant effect on compressive strength (p = 0.05). Compressive strength in all the groups increased over time from day 4 to day 21. However, this increase was not statistically significant (p = 0.06) except for the MTA group, which exhibited significant increase in compressive strength over time from day 4 to day 21 (p =0.007). Conclusion: Incorporation of HA and ZnO nanoparticles into MTA had no detrimental effects on its strength and these nanoparticles can be used to improve the other properties of MTA. [ABSTRACT FROM AUTHOR]

Biosensors combine the sensitivity of detection technology with the specificity of a designated biological entity. Owing to their specificity and sensitivity, biosensors are applied for sensing and monitoring of different diseases. Simultaneous sensing of myriad of biomarkers in different diseases at the early stages is swiftly finding its way towards disease's hallmarks, even though the biological contexts are complex matrices with possible cross-reactivity of restrained biomolecules. Electrochemical biosensors are considered as simple and cost-effective methods, which make the concurrent detection of multiple biomarkers plausible for ultimate diagnosis of diseases in clinic. Simultaneous sensing of multiple biomarkers by electrochemical techniques can be achieved through either multi-label or multi-electrode approaches, which can be implemented as miniaturized screen-printed or even lab-on-a-chip systems. Here, we reviewed literature (2000–2016) and provided a comprehensive insight on various biosensing platforms, articulating the most recent advancements in each type of biosensors applied for the detection of biomolecules. [ABSTRACT FROM AUTHOR]

The brain shows a high sensitivity to oxidative stress (OS). Thus, the maintenance and homeostasis of the brain, in particular neural cells, regarding the reduction-oxidation (redox) situation is crucial for the regular function of the central nervous systems (CNS). The imbalance between the reactive oxygen species (ROS) and the cellular mechanism(s) might lead to the emergence of OS, resulting in possible cell death and tissue damages, and initiating neurodegenerative disorders (NDDs). Characterized by the cytoplasmic growth of neurofibrillary tangles and extracellular β-amyloid plaques, Alzheimer's disease (AD) is a complex NDD that causes dementia in adult life with severe manifestations. Nuclear factor erythroid 2-related factor 2 (NRF2) is a key transcription factor that regulates the functional expression of OS-related genes and the functionality of endogenous antioxidants in response to ROS. In the case of oxidative damage, NRF2 is transferred to the nucleus and attached to the antioxidant response element (ARE), which can subsequently enhance the functional expression of the cell-protecting genes. In this review, we impart on the key mechanisms engaged in the generation of active and reactive species of endogenous and exogenous oxidants and discuss the antioxidants as the defense system of neural cells regarding the NRF2-ARE signaling path in the CNS. • The neural cells and brain functions are highly sensitive to oxidative stress (OS). • Balanced reduction-oxidation (redox) situation is crucial for the regular function of the central nervous systems. • An imbalance between the reactive oxygen species and the cellular mechanism might induce OS in the brain. • The occurrence of OS in the brain may cause profound cell damages and provoke neurodegenerative disorders. • Nuclear factor erythroid 2-related factor 2 and antioxidant response element modulate the OS-related genes. [ABSTRACT FROM AUTHOR]

• The computational prediction of aptamer interactions can be useful to provide guidelines for effective aptamer selection and designing with high affinity. • The computational structure prediction can be helpful to improve the selection to have a wider sort of structures and prepares necessary information to simulate molecular docking. • The structure prediction is performed through either sequence-based prediction or structure-based prediction. • Secondary structure prediction methods can be divided into two general categories: single-sequence analysis and multiple sequence analysis. • 3D structure prediction is achieved through template-based and free modeling-based methods. Aptamers are short single-strand sequences that can bind to their specific targets with high affinity and specificity. Usually, aptamers are selected experimentally via systematic evolution of ligands by exponential enrichment (SELEX), an evolutionary process that consists of multiple cycles of selection and amplification. The SELEX process is expensive, time-consuming, and its success rates are relatively low. To overcome these difficulties, in recent years, several computational techniques have been developed in aptamer sciences that bring together different disciplines and branches of technologies. In this paper, a complementary review on computational predictive approaches of the aptamer has been organized. Generally, the computational prediction approaches of aptamer have been proposed to carry out in two main categories: interaction-based prediction and structure-based predictions. Furthermore, the available software packages and toolkits in this scope were reviewed. The aim of describing computational methods and tools in aptamer science is that aptamer scientists might take advantage of these computational techniques to develop more accurate and more sensitive aptamers. [ABSTRACT FROM AUTHOR]

Breast cancer (BC) is one of the most common cancers in women, and chemotherapy is usually used to overcome this cancer. To improve drug delivery to cancer sites and reduce their side effects, nanocarriers such as niosomes (NIOs) are used. Moreover, a combination of other therapeutic methods like photothermal therapy (PTT) can help to enhance the chemotherapy effect. The aim of this research is the design a nanocarrier that simultaneously delivers chemotherapy and PTT agents. To achieve this goal, NIOs containing paclitaxel (PTX) as a chemotherapeutic agent and spherical gold nanoparticles (AuNPs) coated with citrate, chitosan (CS), and polyamidoamine (PAMAM) as a PTT agent were synthesized by thin hydration methods. Their physicochemical properties were determined by dynamic light scattering, UV-Vis, Fourier-transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM) analysis. Cellular uptake, cell cytotoxicity, hyperthermia, and apoptosis effects of the proposed system were investigated in the MCF-7 BC cell line. The cellular uptake of NIOs/AuNPs-PAMAM (99.21%) and NIOs/AuNPs-CS (98.93%) by MCF-7 cells was higher than that of NIOs/AuNPs (79.55%), demonstrating that surface charge plays a key role in the cellular uptake of NPs. The MTT assay showed the cell viability of 45.48% for NIOs/AuNPs/PTX, 34.24% for NIOs/AuNPs-CS/PTX, and 37.67% for NIOs/AuNPs-PAMAM/PTX after 48 h of treatment. However, the application of hyperthermia significantly decreased the viability of cells treated with NIOs/AuNPs/PTX (37.72%), NIOs/AuNPs-CS/PTX (10.49%), and NIOs/AuNPs-PAMAM/PTX (4.1%) after 48 h. The apoptosis rate was high in NIOs/AuNPs-PAMAM/PTX (53.24%) and NIOs/AuNPs-CS/PTX (55.4%) confirming the data from MTT. In conclusion, the result revealed that combined PTT with chemotherapy increased cell cytotoxicity effects against the MCF-7 cells, and the AuNPs with various coating agents affected cellular uptake and hyperthermia which can be considered for efficient BC therapy., (© 2024 IOP Publishing Ltd.)