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581.
As the most common cancer in women, efforts have been made to develop novel nanomedicine-based therapeutics for breast cancer. In the present study, the in silico curcumin (Cur) properties were investigated, and we found some important drawbacks of Cur. To enhance cancer therapeutics of Cur, three different nonionic surfactants (span 20, 60, and 80) were used to prepare various Cur-loaded niosomes (Nio-Cur). Then, fabricated Nio-Cur were decorated with folic acid (FA) and polyethylene glycol (PEG) for breast cancer suppression. For PEG-FA@Nio-Cur, the gene expression levels of Bax and p53 were higher compared to free drug and Nio-Cur. With PEG-FA-decorated Nio-Cur, levels of Bcl2 were lower than the free drug and Nio-Cur. When MCF7 and 4T1 cell uptake tests of PEG-FA@Nio-Cur and Nio-Cur were investigated, the results showed that the PEG-FA-modified niosomes exhibited the most preponderant endocytosis. In vitro experiments demonstrate that PEG-FA@Nio-Cur is a promising strategy for the delivery of Cur in breast cancer therapy. Breast cancer cells absorbed the prepared nanoformulations and exhibited sustained drug release characteristics.  相似文献   
582.
Stingless bee honey has a distinctive flavor and sour taste compared to Apis mellifera honey. Currently, interest in farming stingless bees is growing among rural residents to meet the high demand for raw honey and honey-based products. Several studies on stingless bee honey have revealed various therapeutic properties for wound healing applications. These include antioxidant, antibacterial, anti-inflammatory, and moisturizing properties related to wound healing. The development of stingless bee honey for wound healing applications, such as incorporation into hydrogels, has attracted researchers worldwide. As a result, the effectiveness of stingless bee honey against wound infections can be improved in the future to optimize healing rates. This paper reviewed the physicochemical and therapeutic properties of stingless bee honey and its efficacy in treating wound infection, as well as the incorporation of stingless bee honey into hydrogels for optimized wound dressing.  相似文献   
583.
584.
Diabetes mellitus is a chronic complication that affects people of all ages. The increased prevalence of diabetes worldwide has led to the development of several synthetic drugs to tackle this health problem. Such drugs, although effective as antihyperglycemic agents, are accompanied by various side effects, costly, and inaccessible to the majority of people living in underdeveloped countries. Medicinal plants have been used traditionally throughout the ages to treat various ailments due to their availability and safe nature. Medicinal plants are a rich source of phytochemicals that possess several health benefits. As diabetes continues to become prevalent, health care practitioners are considering plant-based medicines as a potential source of antidiabetic drugs due to their high potency and fewer side effects. To better understand the mechanism of action of medicinal plants, their active phytoconstituents are being isolated and investigated thoroughly. In this review article, we have focused on pharmacologically active phytomolecules isolated from medicinal plants presenting antidiabetic activity and the role they play in the treatment and management of diabetes. These natural compounds may represent as good candidates for a novel therapeutic approach and/or effective and alternative therapies for diabetes.  相似文献   
585.
Middle East respiratory syndrome coronavirus (MERS-CoV), belonging to the betacoronavirus genus can cause severe respiratory illnesses, accompanied by pneumonia, multiorgan failure, and ultimately death. CoVs have the ability to transgress species barriers and spread swiftly into new host species, with human-to-human transmission causing epidemic diseases. Despite the severe public health threat of MERS-CoV, there are currently no vaccines or drugs available for its treatment. MERS-CoV papain-like protease (PLpro) is a key enzyme that plays an important role in its replication. In the present study, we evaluated the inhibitory activities of doxorubicin (DOX) against the recombinant MERS-CoV PLpro by employing protease inhibition assays. Hydrolysis of fluorogenic peptide from the Z-RLRGG-AMC–peptide bond in the presence of DOX showed an IC50 value of 1.67 μM at 30 min. Subsequently, we confirmed the interaction between DOX and MERS-CoV PLpro by thermal shift assay (TSA), and DOX increased ΔTm by ~20 °C, clearly indicating a coherent interaction between the MERS-CoV PL protease and DOX. The binding site of DOX on MERS-CoV PLpro was assessed using docking techniques and molecular dynamic (MD) simulations. DOX bound to the thumb region of the catalytic domain of the MERS-CoV PLpro. MD simulation results showed flexible BL2 loops, as well as other potential residues, such as R231, R233, and G276 of MERS-CoV PLpro. Development of drug repurposing is a remarkable opportunity to quickly examine the efficacy of different aspects of treating various diseases. Protease inhibitors have been found to be effective against MERS-CoV to date, and numerous candidates are currently undergoing clinical trials to prove this. Our effort follows a in similar direction.  相似文献   
586.
Engineering the electronic excited state manifolds of organic molecules can give rise to various functional outcomes, including ambient triplet harvesting, that has received prodigious attention in the recent past. Herein, we introduce a modular, non-covalent approach to bias the entire excited state landscape of an organic molecule using tunable ‘through-space charge-transfer’ interactions with appropriate donors. Although charge-transfer (CT) donor–acceptor complexes have been extensively explored as functional and supramolecular motifs in the realm of soft organic materials, they could not imprint their potentiality in the field of luminescent materials, and it still remains as a challenge. Thus, in the present study, we investigate the modulation of the excited state emission characteristics of a simple pyromellitic diimide derivative on complexation with appropriate donor molecules of varying electronic characteristics to demonstrate the selective harvesting of emission from its locally excited (LE) and CT singlet and triplet states. Remarkably, co-crystallization of the pyromellitic diimide with heavy-atom substituted and electron-rich aromatic donors leads to an unprecedented ambient CT phosphorescence with impressive efficiency and notable lifetime. Further, gradual minimizing of the electron-donating strength of the donors from 1,4-diiodo-2,3,5,6-tetramethylbenzene (or 1,2-diiodo-3,4,5,6-tetramethylbenzene) to 1,2-diiodo-4,5-dimethylbenzene and 1-bromo-4-iodobenzene modulates the source of ambient phosphorescence emission from the 3CT excited state to 3LE excited state. Through comprehensive spectroscopic, theoretical studies, and single-crystal analyses, we elucidate the unparalleled role of intermolecular donor–acceptor interactions to toggle between the emissive excited states and stabilize the triplet excitons. We envisage that the present study will be able to provide new and innovative dimensions to the existing molecular designs employed for triplet harvesting.

A modular, non-covalent donor–acceptor strategy is proposed to bias the excited-state manifold of organic systems and to realize unprecedented charge-transfer phosphorescence.  相似文献   
587.
Graphitic carbon nitride (g-C3N4) has gained tremendous interest in the sector of power transformation and retention, because of its distinctive stacked composition, adjustable electronic structure, metal-free feature, superior thermodynamic durability, and simple availability. Furthermore, the restricted illumination and extensive recombination of photoexcitation electrons have inhibited the photocatalytic performance of pure g-C3N4. The dimensions of g-C3N4 may impact the field of electronics confinement; as a consequence, g-C3N4 with varying dimensions shows unique features, making it appropriate for a number of fascinating uses. Even if there are several evaluations emphasizing on the fabrication methods and deployments of g-C3N4, there is certainly an insufficiency of a full overview, that exhaustively depicts the synthesis and composition of diverse aspects of g-C3N4. Consequently, from the standpoint of numerical simulations and experimentation, several legitimate methodologies were employed to deliberately develop the photocatalyst and improve the optimal result, including elements loading, defects designing, morphological adjustment, and semiconductors interfacing. Herein, this evaluation initially discusses different dimensions, the physicochemical features, modifications and interfaces design development of g-C3N4. Emphasis is given to the practical design and development of g-C3N4 for the various power transformation and inventory applications, such as photocatalytic H2 evolution, photoreduction of CO2 source, electrocatalytic H2 evolution, O2 evolution, O2 reduction, alkali-metal battery cells, lithium-ion batteries, lithium–sulfur batteries, and metal-air batteries. Ultimately, the current challenges and potential of g-C3N4 for fuel transformation and retention activities are explored.  相似文献   
588.
A general expression of Clebsch-Gordan coefficients is derived by means of de Broglie-like méthode de fusion: the second angular momentum is added to the first in n steps of half each, the maximum symmetric composition of the n spin functions being taken into account explicitly. The procedure is operatorial. Group-theoretically speaking the irreducible representations of the direct product of two irreducible representations of the rotation group are realized via symmetric group Sn with the aid of projection operators (equivalent to Young's symmetrizers). The decomposition of the representations of Sn therein is performed inductively by utilizing the chain of subgroups: SnSn−1 … ⊃ S2S1.  相似文献   
589.
The present paper reports the theory of crystalloluminescence (CRL) produced during the micro-fracture of growing crystallites. Surface charges may be developed during the micre-fracture of crystallites due to several processes like piezoelectrification, movement of charged dislocations, barodiffusion of defects near the moving crack etc. The surface charges may be neutralized by the movement of charge carriers produced due to the dielectric breakdown near the surface of crystallites and consequently the recombination luminescence may occur. Considering the basic concepts of crystallization from the supersaturated solution, expressions are derived which are able to explain satisfactorily the temporal, thermal, spectral concentration and other characteristics of the CRL. It is shown that the induction period for crystal nucleation, lifetime of supersaturation, size of crystallites and time constant for the relaxation of charges on the newly created surfaces may be determined from the CRL measurements.  相似文献   
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