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Hydrogen has received a lot of attention and is regarded as the most promising energy source of the twenty-first century because of its high energy density and eco-friendliness. However, there are increasing concerns about its safe use, storage, and transportation. The present research study scrutinizes the chemi-resistive behavior of pure and Cu-doped TiO2 thin films that may be applied to the creation of hydrogen sensing devices. The spray technique was used to synthesize the samples with different levels of Cu content (0, 0.2 and 0.4 wt %) on thermally oxidized Si substrates. The samples were characterized by grazing incidence X-ray diffraction (GIXRD), atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM), and energy dispersive X-ray (EDX) analysis. The hydrogen chemi-resistive behavior of the samples was assessed and the sensing mechanism of the pure and doped samples was analyzed. The results showed that Cu-doping significantly affected the hydrogen sensing performance of the TiO2 thin films due to the increase of oxygen adsorption sites. The sample of 0.4 wt % Cu-doped TiO2 (the most sensitive sample) showed a response value of 2600% with a reaction time of 55 s to 1000 ppm of hydrogen at the operating temperature of 200 °C. It was also selective to H2 compared to CO2, NO2, NH3, and LPG. The evaluation of the reliability of the mentioned sample revealed that it can be considered as a potential for hydrogen sensing devices. [ABSTRACT FROM AUTHOR]

Maryam Dibaei,1 Mohammad-Reza Rouini,1 Behjat Sheikholeslami,1 Mahdi Gholami,2,3 Rassoul Dinarvand4,51Biopharmaceutics and Pharmacokinetic Division, Department of Pharmaceutics, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran; 2Experimental Medicine Research Center, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran; 3Department of Pharmacology and Toxicology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran; 4Nanotechnology Research Centre, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran; 5Department of Pharmaceutics, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, IranBackground: Curcumin, a bioactive component with multiple characteristics, has been shown to have many therapeutic effects. However, there are several limitations regarding the use of curcumin such as instability, low solubility, poor bioavailability, and rapid elimination. Different approaches have been used to solve these problems.Materials and methods: In this study, surface-modified nanosuspension (NS) is investigated as a novel brain delivery system. Two different methods were used for the preparation of nanosuspensions with two different stabilizers. The surface of the nanosuspensions was coated with D-α-tocopheryl polyethylene glycol 1,000 succinate (TPGS) and Tween 80 using physical adsorption. Curcumin NSs were prepared using two different top-down techniques by high-pressure homogenizer and probe sonicator. A validated sensitive and selective high-performance liquid chromatography method using fluorescence detection was used for the determination and quantification of curcumin. Pharmacokinetics and biodistribution of curcumin NSs and solutions after intravenous administration in rats were studied.Results: Higher levels of curcumin in the brain were detected when Tween 80-coated NS was used compared with the curcumin solution and TPGS coated NS (TPGS-NS) (P-value

Mohaddeseh Salehi,1,* Mona Amin-Beidokhti,2,* Behnam Safarpour Lima,3 Milad Gholami,2 Gholam-Reza Javadi,1 Reza Mirfakhraie2,4 1Department of Biology, Islamic Azad University, Science and Research Branch, 2Department of Medical Genetics, 3Department of Neurology, School of Medicine, 4Genomic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran *These authors contributed equally to this work Introduction: Migraine is a painful complex neurovascular disease characterized by recurrent moderate-to-severe headaches. Increased level of homocysteine is related to dilation of cerebral vessels and endothelial injury that could trigger migraine attacks. Functional polymorphisms in the MTHFR gene affect homocysteine metabolism and, therefore, play an important role in the etiology of the disease. Objectives: We aimed to investigate the possible association between MTHFR gene rs4846049, C677T, and A1298C polymorphisms and the risk of migraine in Iranian population. Methods: In this genetic association study, 498 individuals were enrolled, including 223 migraine patients and 275 healthy controls. Genotyping was performed using tetra-primer ARMS-PCR for rs4846049 and PCR-restriction fragment length polymorphism for C677T and A1298C polymorphisms. Results: The association between rs4846049 and C677T polymorphisms and migraine was observed. For the rs4846049 polymorphism, the association was detected under a dominant model (P=0.007; odds ratio [OR] =0.60; 95% confidence interval [CI], 0.41–0.87), and for the C677T polymorphism, the TT genotype frequency was significantly different in the studied groups (P=0.009; OR =2.48; 95% CI, 1.25–4.92). No significant differences in the genotype or allele frequencies were found for the A1298C polymorphism between the migraineurs and controls. Conclusion: Present data provide evidence for the association of rs4846049 and C677T polymorphisms in the MTHFR gene and migraine. Further studies are required to validate the significance of the studied genetic variations in diverse ethnic populations. Keywords: migraine, genetic association study, MTHFR, single nucleotide polymorphism