A Facile Method to Synthesize 3D Pomegranate-like Polydopamine Microspheres

Nanospheres have found versatile applications in the biomedical field; however, their possible harmful effects on immune and inflammatory systems are also a crucial concern. Inspired by a pomegranate structure, we demonstrated a novel structure for the nanostructured microspheres to overcome the drawbacks of nanospheres without compromising their merits. In this study, 3D pomegranate-like polydopamine microspheres (PDAMS) were synthesized by self-oxidative polymerization of dopamine hydrochloride. Herein, controlling the pH during polymerization led to synthesizing homogeneous agglomerated nano-sized spheres (400–2000 nm) and finally forming tunable and monodisperse micron-sized particles (21 µm) with uniform spherical shape porous microstructure. PDAMS interaction with the potential targets, Bone morphogenetic protein-2 (BMP2), Decorin, and Matrilin-1, was investigated via molecular calculations. Theoretical energy analysis revealed that PDAMS interaction with BMP2, Decorin, and Matrilin-1 is spontaneous, so that a protein layer formation on the PDAMS surface suggests application in bone and cartilage repair. It was also observed that PDAMS presented in-vitro degradation within 4 weeks. Here, disappearance of the UV-VIS spectrum peak at 280 nm is accompanied by the degradation of catechol groups. Pomegranate-like PDAMS support the biomimetic formation of hydroxyapatite-like layers, making them appropriate candidates for hard tissue applications. Herein, the appearance of peaks in XRD spectrum at 31.37, 39.57, 45.21, and 50.13° attributed to hydroxyapatite-like layers formation. All these results demonstrated that self-oxidative polymerization under a controllable pH can be a green and straightforward technique for preparing the pomegranate-like PDAMS and providing an innovative basis for further pre-clinical and clinical investigations

The in silico insight into carbon nanotube and nucleic acid bases interaction

Background: To explore practical applications of carbon nanotubes (CNTs) in biomedical fields the properties of their interaction with biomolecules must be revealed. Recent years, the interaction of CNTs with biomolecules is a subject of research interest for practical applications so that previous research explored that CNTs have complementary structure properties with single strand DNA (ssDNA). Objectives: Hence, the quantum mechanics (QM) method based on ab initio was used for this purpose. Therefore values of binding energy, charge distribution, electronic energy and other physical properties of interaction were studied for interaction of nucleic acid bases and SCNT. Materials and Methods: In this study, the interaction between nucleic acid bases and a (4, 4) single-walled carbon nanotube (SCNT) were investigated through calculations within quantum mechanics (QM) method at theoretical level of Hartree-Fock (HF) method using 6-31G basis set. Hence, the physical properties such as electronic energy, total dipole moment, charge distributions and binding energy of nucleic acid bases interaction with SCNT were investigated based on HF method. Results: It has been found that the guanine base adsorption is bound stronger to the outer surface of nanotube in comparison to the other bases, consistent with the recent theoretical studies. In the other words, the results explored that guanine interaction with SCNT has optimum level of electronic energy so that their interaction is stable. Also, the calculations illustrated that SCNT interact to nucleic acid bases by noncovalent interaction because of charge distribution an electrostatic area is created in place of interaction. Conclusions: Consequently, small diameter SCNT interaction with nucleic acid bases is noncovalent. Also, the results revealed that small diameter SCNT interaction especially SCNT (4, 4) with nucleic acid bases can be useful in practical application area of biomedical fields such detection and drug delivery. © 2016, Iranian Red Crescent Medical Journal

Modelling Temperature Variation of Mushroom Growing Hall Using Artificial Neural Networks

The recent developments of computer and electronic systems have made the use of intelligent systems for the automation of agricultural industries. In this study, the temperature variation of the mushroom growing room was modeled by multi-layered perceptron and radial basis function networks based on independent parameters including ambient temperature, water temperature, fresh air and circulation air dampers, and water tap. According to the obtained results from the networks, the best network for MLP was in the second repetition with 12 neurons in the hidden layer and in 20 neurons in the hidden layer for radial basis function network. The obtained results from comparative parameters for two networks showed the highest correlation coefficient (0.966), the lowest root mean square error (RMSE) (0.787) and the lowest mean absolute error (MAE) (0.02746) for radial basis function. Therefore, the neural network with radial basis function was selected as a predictor of the behavior of the system for the temperature of mushroom growing halls controlling system

Acceptance of shari?ah-compliant precious metal-backed cryptocurrency as an alternative currency: an empirical validation of adoption of innovation theory

In the crypto world, there is a proverbial (and literal) gold rush now occurring. Currently, more than 37 gold-backed cryptocurrency companies have now emerged. Interestingly, some of them also claim to be Sharīʿah-compliant. Introducing precious metal-backed cryptocurrencies is perceived to be an innovation among global payment systems, hampered in part by lack of supporting empirical evidence. Therefore, this research investigates potential users' tendency to adopt a Sharīʿah-compliant precious metal-backed cryptocurrency. As such, this study adopts an extended adoption model, which consists of eight factors. Partial least squares structural equation modeling (PLS-SEM) analysis was conducted on data elicited from economic active residents in Klang Valley from questionnaires. Overall, it was found six out of the eight constructs specified to influence the adoption of precious metal-backed cryptocurrency were statistically significant where 54.5% of the variation in adoption of PMBC can be explained by the structure model provided by this research. It was also found 63.55% of the respondents are willing to adopt precious metal-backed cryptocurrency in their future transactions

Effect of Plant Density on Growth and Yield of Three Sunflower Hybrids (Helianthus annuus L.) as a Second Crop

In order to study the effects of plant density on growth, yield and oil percentage of three sunflower hybrids (Azargol, Alistar, Eroflor) an experiment was conducted at Agriculture Research Station of Myandoab in 2004. These hybrids were sown at four densities of 6, 8, 10 and 12 plants m-2 as factorial based on randomized complete block design with three replications. The results showed that dry matter accumulation (DM), crop growth rate (CGR) and relative growth rate (RGR) were increased with increasing plant density. By increment plant density, leaf area index (LAI) was slowly increased in early stages of growth but with beginning of plant rapid growth, increased dramatically. DM and CGR in Azargol and Eroflor were greater than Alistar. Analysis of variance showed that all traits were significantly affected by plant density. Yield per unit area, oil percentage and oil yield per unit area were increased, with increasing plant density. Although seed yield per plant at low densities was greater than that of high densities, but this increment was not enough for compensating the reduction of yield due to low density

Microtubule network as a potential candidate for targeting by gold nanoparticle-assisted photothermal therapy

Photothermal therapy is achieving ever-increasing attention as a promising method for killing cancer cells. Although, gold nanoparticles are regarded as one of the most effective photothermal therapy agents, the mechanisms underlying their action have to be addressed. Moreover, studies have showed that gold nanoparticles induce apoptosis in treated cultures. Hence, in this study, we investigated the interaction of folic acid functionalized gold nanoparticles and gold-shelled Fe 3 O 4 nanoparticles with microtubule and microtubule associated protein tau in order to introduce intracellular targets of these nanoparticles and provide a holistic view about the mechanism of action of gold nanoparticles used in photothermal therapy. Various spectroscopic methods were used to find gold nanoparticles interaction with Tubulin and Tau. Our results indicated that these gold nanoparticles interact with both Tau and Tubulin and their affinity increases as temperature rises. Also, the results illustrated that quenching mechanism for gold nanoparticles interaction with Tubulin and Tau was static. The hydrophobic interaction was determined as driving force for gold nanoparticles binding to Tubulin and Tau. Moreover, it was showed that both type of gold nanoparticles stabilize microtubule polymers. These results suggest Tau and Tubulin as intracellular target of gold nanoparticles and propose that microtubule network is at the heart of apoptosis mechanisms initiated by photothermal therapy. © 201

The measurement and mathematical analysis of 5-Fu release from magnetic polymeric nanocapsules, following the application of ultrasound

Objective: To study the effects of ultrasound irradiation on the release profile of 5-fluorouracil (5-Fu) loaded magnetic poly lactic co-glycolic acid (PLGA) nanocapsules. Also, the controlled drug-release behaviour of the nanocapsules was mathematically investigated. Methods: The nanocapsules were synthesized, dispersed in phosphate buffered saline (PBS), transferred to a dialysis bag, and finally, irradiated by various ultrasound parameters (1 or 3MHz; 0.3-1W/cm2; 5-10 minutes). The release profile of the irradiated nanocapsules was recorded for 14 days. To find the in vitro drug release mechanism in the absence and presence of various intensities of ultrasound, the obtained data were fitted in various kinetic models for drug release. Results: The results demonstrated that the ultrasound speeded up the rate of drug release from the nanocapsules. The mathematical analysis illustrated that when the ultrasound intensity is increased, the probability of controlled release behaviour of the nanocapsules is raised. We found that drug release from the irradiated nanocapsules follows an erosion-controlled mechanism with the decrease in the velocity of diffusion. Conclusion: In conclusion, to attain a controlled drug-delivery strategy in the area of cancer therapy, the drug release profile of the nano-carriers may be well-controlled by ultrasound. © 2018 Bentham Science Publishers

Selective apoptosis induction in cancer cells using folate-conjugated gold nanoparticles and controlling the laser irradiation conditions

In this study, we explained in detail a targeted nano-photo-thermal therapy (NPTT) method to induce selective apoptosis in cancer cells. Folate-conjugated gold nanoparticles (F-AuNPs) were synthesized by tailoring the surface of AuNPs with folic acid to enhance the specificity of NPTT. KB cancer cells, as a folate receptor over-expressing cell line, and L929 normal cells with low level of folate receptors were incubated with the synthesized F-AuNPs and then irradiated with various laser intensities and exposure durations. Following various regimes of NPTT, we assessed the level of cell viability and the ratio of apoptosis/necrosis. No significant cytotoxicity was observed for both cell lines at concentrations up to 40�μM of F-AuNPs. Moreover, no significant cell lethality occurred for various laser irradiation conditions. The viability of KB and L929 cells incubated with F-AuNPs (40�μM; 6�h) and then irradiated by laser (1�W/cm2; 2�min) was 57 and 83, respectively. It was also demonstrated that the majority of cancer cell death is related to apoptosis (41 apoptosis of 43 overall cell death). In this process of F-AuNPs based NPTT, it may be concluded that the main factor determining whether a cell dies due to apoptosis or necrosis depends on laser irradiation conditions. In this study, we explained in detail a targeted nano-photo-thermal therapy (NPTT) method to induce selective apoptosis in cancer cells. © 2018 Informa UK Limited, trading as Taylor & Francis Grou

The effects of gold nanoparticles characteristics and laser irradiation conditions on spatiotemporal temperature pattern of an agar phantom: A simulation and MR thermometry study

In this paper, the effects of parameters related to gold nanoparticles (type, size, and concentration) and the laser parameters on spatiotemporal temperature pattern of an agar phantom during a photothermal therapy (PTT) procedure were modeled and then experimentally verified. Eight agar phantoms loaded by gold nanoparticles were made. An agar phantom without any nanoparticles was also considered as the control. Different sizes of two types of gold nanoparticles (spherical and silica-gold core shell) at various concentrations were studied. The phantoms were irradiated by various laser powers for 5 min. The temperature changes in each phantom was firstly calculated using COMSOL Multiphysics software. Also, each phantom was irradiated by laser and MR thermometry was performed to validate the simulation results. A reasonable correlation between simulation and MR thermometry was obtained (R = 0.92). The error interval between calculations and experiments was ranged from ±3 to ±6. It was clearly evident that laser irradiation conditions and nanoparticle characteristics affected the temperature rise profile. Spherical 20 nm gold nanoparticles had better thermal efficiency and generated higher level of heat. The protocol suggested in this study may be appropriate to make a pre-clinical calculation and effect visualization for any nanoparticles-based PTT procedure before entrance into the clinics. © 2019 Elsevier Gmb