Ugi Bis-Amide Derivatives as Tyrosinase Inhibitor; Synthesis,Biology Assessment,and in Silico Analysis

Herein, a straightforward synthetic strategy mediated by Ugi reaction was developed to synthesize novel series of compounds as tyrosinase inhibitors. The structures of all compounds were confirmed by FT-IR, ¹H-NMR, ¹³C-NMR, and CHNOS techniques. The tyrosinase inhibitory activities of all synthesized derivatives 5a – m were determined against mushroom tyrosinase and it was found that derivative 5c possesses the best inhibition with an IC₅₀ value of 69.53±0.042 μM compared to the rest of the synthesized derivatives. Structure–activity relationships (SARs) showed that the presence of 4-MeO or 4-NO₂ at the R² position plays a key role in tyrosinase inhibitory activities. The enzyme kinetics studies showed that compound 5c is an noncompetitive inhibitor. For in silico study, the allosteric site detection was first applied to find the appropriate binding site and then molecular docking and molecular dynamic studies were performed to reveal the position and interactions of 5c as the most potent inhibitor within the tyrosinase active site. The results showed that 5c bind well with the proposed binding site and formed a stable complex with the target protein.     

Biology of Allothrombium pulvinum Ewing (Acari: Trombidiidae) in West Mazandran, Iran

Allothrombium pulvinum Ewing is a common natural enemy of aphids and other arthropods in Iran. It is univoltine in Iran. The eggs hatch in spring, nymphs emerge in early summer and adults appear in autumn. Larvae are ectoparasites of aphids whereas deutonymphs and adults are free-living predators of aphids and spider mites. Adults hibernate in the soil and in cracks of tree trunks during winter. When spring comes, females lay eggs in the soil, on the soil surface and on weeds. Phytoseius plumifer (Phytoseiidae) was observed to be phoretic on deutonymphs of A. pulvinum on nettle trees (Celtis australis). In the laboratory, development from the egg to adult stage takes at least 107 days at 25±1°C. Soil is not essential for female oviposition. High humidity is the most important factor for oviposition and development in A. pulvinum.     

Selenium nano-particle induced alterations in expression patterns of heat shock factor A4A (HSFA4A), and high molecular weight glutenin subunit 1Bx (Glu-1Bx) and enhanced nitrate reductase activity in wheat (<Emphasis Type="Italic">Triticum aestivum</Emphasis> L.)

Taking account of heat shock factor A4A (HSFA4A) as a hydrogen peroxide sensor, anti-apoptosis agent, and crosslink component with critical signaling cascades, the current study was carried out to monitor possible changes in expression of this gene as well as some other important characteristics in wheat plants exposed to selenium nano-particle (nSe). Wheat seedlings were treated with nSe (0, 5, 10, and 50 mgl^?1). In germinating stage, plant fresh weights were reduced in nSe-treated seedlings, among which the nSe of 50 provoked roots turned brown. The nSe triggered the increases in the expressions of HSFA4A, in the plate. In the pot condition, shoot fresh weights in nSe-supplemented seedlings were decreased by approximately 22%. The nSe of 5 and 10 mgl^?1, respectively induced the expression of HSFA4A by 3.4- and 9.15-folds, contrasted with nSe50. Increasing times of sprays caused the dramatic reductions of the expression of HSFA4A in the nSe-supplemented groups. Moreover, the treatment of nSe stimulated expression of high molecular weight glutenin subunit 1Bx (Glu-1Bx) by fourfold, over the control. While the dramatic decrease in the expression of Glu-1Bx was recorded with increasing times of spray. Nitrate reductase activities were significantly improved by approximately 47% in nSe-fortified seedlings. Also, the foliar supplementation of nSe of 5 mgl^?1 provoked the significant inductions in peroxidase activity by 8%, whereas two other nSe treatments declined it. It may be stated that the nSe may modify the expression of HSFA4A, thereby triggering specific signaling and altering metabolism.     

Tragacanth-mediate synthesis of NiO nanosheets for cytotoxicity and photocatalytic degradation of organic dyes

Bioprocess and Biosystems Engineering - In this study, NiO nanosheets have been manufactured using a co-precipitation approach that involved the usage of nickel nitrate (Ni (NO3)2.6H2O) as the raw...     

Performance Enhancement of Surface Plasmon Resonance Biosensors Based on Noble Metals-Graphene-WS2 at Visible and Near-Infrared Wavelengths

Plasmonics - In this paper, some biological sensors based on surface plasmon resonance are proposed at visible and near-infrared wavelengths and their performance is improved. The structure of...     

Investigating the association between rs6983267 polymorphism and susceptibility to gastrointestinal cancers in Iranian population

Molecular Biology Reports - Genome-wide association studies have revealed that some single nucleotide polymorphisms at 8q24, such as rs6983267, might be effective in susceptibility to various...     

Evaluating cytotoxic effect of nanoliposomes encapsulated with umbelliprenin on 4T1 cell line

Cytotoxicity of umbelliprenin has been found in various cancer cell lines such as, prostate, breast, CLL, and skin. Encapsulating chemotherapeutic agents with nanoliposomes have been resulted in improved cytotoxicity effects than their free forms. However, whether nanoliposomal form of umbelliprenin could have higher cytotoxic effect than free umbelliprenin is not clarified yet. After synthesizing umbelliprenin, different concentrations (3, 6, 12, 25, 50, 100, 200 μg/ml) applied on the mouse mammary carcinoma cell line (4T1) for 24, 48, and 72 h at 37°C. Afterwards, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was performed to analyze cytotoxicity. MTT assay results showed that IC₅₀ of umbelliprenin in dimethyl sulfoxide (DMSO) (30.92, 30.64, and 62.23 for 24, 48, 72 h incubation, respectively) decreased (5.8, 5.0, 3.5 for 24, 48, 72 h incubation, respectively) when encapsulated with nanoliposomes. Nanoliposomal umbelliprenin cytotoxicity affected cell viability in concentration and time-dependent manner. Our study recommended nanoliposomal umbelliprenin as the most effective chemotherapeutic agent against the mouse mammary carcinoma cell line viability. Future in vivo studies and clinical trials are needed.     

Rapid suppression and sustained activation of distinct cortical regions for a delayed sensory-triggered motor response

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