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991.
Mengyao Yang Xingshu Li Gyoungmi Kim Rui Wang Seong-Jin Hong Chang-Hee Lee Juyoung Yoon 《Chemical science》2022,13(43):12738
Phototherapy has been a promising therapeutic modality for pathological tissue due to its spatiotemporal selectivity and non-invasive characteristics. However, as a core component of phototherapy, a single photosensitizer (PS) nanoplatform integrating excellent therapeutic efficiency and minimal side effects remains an urgent but unmet need. Here, we construct a J-aggregated nano-porphyrin termed MTE based on the self-assembly of methyl-pheophorbide a derivative MPa-TEG (MT) and natural polyphenolic compound epigallocatechin gallate (EGCG). Due to the synergistic interaction between similar large π-conjugated structural EGCG and MT, MTE with small and uniform size is obtained by effectively hindering Ostwald ripening of MT. Noteworthily, MTE not only effectively avoids the inadvertent side effects of phototoxicity during transport thank to the ability of reactive oxygen species (ROS) scavenging, but also achieves two-pathway augmented superior phototherapy: (1) enhancing photodynamic therapy (PDT) via inhibiting the expression of anti-apoptosis protein surviving; (2) achieving adjuvant mild-temperature laser interstitial thermal therapy (LITT) via reducing the tumor thermoresistance on account that MTE inhibits the overexpression of HSP 70 and HSP 90. This research not only offers a facile strategy to construct multicomponent nanoplatforms but also provides a new pathway for efficient and low-toxicity phototherapy, which is beneficial to the future clinical application.J-aggregated nanoporphyrin (MTE) integrates minimal side effects and two-pathway augmented superior phototherapy: enhancing photodynamic therapy (PDT) and achieving adjuvant mild-temperature laser interstitial thermal therapy (LITT). 相似文献
992.
Junming Zhang Xueli Cao Ya-Fei Jiang Sung-Fu Hung Wei Liu Hong Bin Yang Cong-Qiao Xu Dong-Sheng Li Tianyu Zhang Yujing Li Jun Li Bin Liu 《Chemical science》2022,13(41):12114
Inducing the surface enrichment of active noble metal can not only help to stabilize the catalyst but also modify the catalytic performance of the catalyst through electronic and geometric effects. Herein, we report the in situ surface enrichment of Ir on IrRu alloy during the oxygen evolution reaction (OER). The surface enrichment of Ir was probed by ex situ high-resolution transmission electron microscopy (HRTEM), in situ X-ray absorption spectroscopy (XAS), and electrochemical Cu stripping, leading to complementary characterizations of the dynamic reconstruction of the IrRu alloy during OER. Guided by the density functional theory (DFT), an IrRu alloy with low Ir content (20 wt%) was constructed, which displayed a low overpotential of only 230 mV to deliver an OER current density of 10 mA cm−2 in 0.1 M HClO4 solution and maintained stable performance for over 20 h. To investigate the practical application potential, a proton exchange membrane (PEM) water electrolyzer using the IrRu alloy as the anode catalyst was assembled, which required a low cell voltage of only 1.48 V to generate a current density of 1 A cm−2.Inducing the surface enrichment of active noble metal can not only help to stabilize the catalyst but also modify the catalytic performance of the catalyst through electronic and geometric effects. 相似文献
993.
Jianmei Liu Hong Wang Zhi Ma Qianheng Duan Yangyang Fei Xiangdong Meng 《Entropy (Basel, Switzerland)》2022,24(7)
In this paper, we consider the optimization of the quantum circuit for discrete logarithm of binary elliptic curves under a constrained connectivity, focusing on the resource expenditure and the optimal design for quantum operations such as the addition, binary shift, multiplication, squaring, inversion, and division included in the point addition on binary elliptic curves. Based on the space-efficient quantum Karatsuba multiplication, the number of CNOTs in the circuits of inversion and division has been reduced with the help of the Steiner tree problem reduction. The optimized size of the CNOTs is related to the minimum degree of the connected graph. 相似文献
994.
995.
Seulah Lee Man Hyung Koo Dong-Won Han Il-Chan Kim Jun Hyuck Lee Jeong-Hoon Kim Razia Sultana Sun Yeou Kim Ui Joung Youn Jin-Hyoung Kim 《Molecules (Basel, Switzerland)》2022,27(14)
Total fatty-acid (FA) contents of different organs (stomach, liver, brain, and skin) of two Antarctic fish, marbled rockcod (Notothenia rossii) and mackerel icefish (Champsocephalus gunnari), were examined using gas chromatography–mass spectrometry (GC–MS). N. rossii possessed higher contents of total omega-3, where eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), the most represented omega-3 FAs, were distributed throughout all parts of the fish. The highest level of EPA was observed in the skin and that of DHA was observed in the brain of N. rossii. C. gunnari showed organ peculiarity in that most of the omega-3 FAs were found in stomach and skin. Specifically, the highest levels of EPA and DHA were both observed in the stomach. Although N. rossii and C. gunnari both inhabit the Antarctic Southern Oceans, their characteristics in terms of the composition of fatty acids were shown to vary. The extracts were also evaluated for matrix metalloproteinase-1 (MMP-1)-inhibitory activities in UVB-induced human dermal fibroblasts, where extracts of the skin and liver of N. rossii showed the most significant inhibition upon MMP-1 production. These findings provide experimental evidence that the extracts of the Antarctic fish could be utilized as bioactive nutrients, particularly in the enhancement of skin health. 相似文献
996.
In order to overcome the spectral interference of the conventional Fourier transform in the International Electrotechnical Commission framework, this paper introduces a Bregman-split-based compressive sensing (BSCS) method to estimate the Taylor–Fourier coefficients in a multi-frequency dynamic phasor model. Considering the DDC component estimation, this paper transforms the phasor problem into a compressive sensing model based on the regularity and sparsity of the dynamic harmonic signal distribution. It then derives an optimized hybrid regularization algorithm with the Bregman split method to reconstruct the dynamic phasor estimation. The accuracy of the model was verified by using the cross entropy to measure the distribution differences of values. Composite tests derived from the dynamic phasor test conditions were then used to verify the potentialities of the BSCS method. Simulation results show that the algorithm can alleviate the impact of dynamic signals on phasor estimation and significantly improve the estimation accuracy, which provides a theoretical basis for P-class phasor measurement units (PMUs). 相似文献
997.
Sunyeong Jang Hyungju Seo Hojin Kim Hyoyoung Kim Jongsung Ahn Hyunjeong Cho Sunghie Hong Seunghwa Lee Taewoong Na 《Molecules (Basel, Switzerland)》2022,27(14)
A method was developed for the rapid and quantitative analysis of 30 veterinary drugs belonging to 17 classes (amphenicols (1), anthelmintics (1), cephalosporins (4), coccidiostats (1), lincosamides (1), macrolide (1), nitroimidazole (1), penicillins (3), phenylhydrazines (1), polypeptides (1), pyrethrins (1), quinolones (5), sulfonamides (3), tetracycline (3), neuroleptic agents (1), triazene trypanocidal agents (1), other. (1)) in feeds. The proposed method with a modified Quick Polar Pesticides (QuPPe) sample preparation was validated for the determination of 30 veterinary drugs in feed samples by liquid chromatography triple-quadrupole mass spectrometry (LC–MS/MS). The sample was extracted with methanol containing 1% acetic acid and purified by dispersive solid-phase extraction (d-SPE) with C18. Good linearity (r2 ≥ 0.98) was observed, and the LOQ values ranged from 10 to 200 µg/kg. Average recoveries ranged from 70.8 to 118.4%, and the relative standard deviation was ≤ 18.7%. This validated method was used in the determination of 30 veterinary drugs in 142 feed samples obtained from South Korea. The results show that lincomycin was present in only one of the tested feed samples, although it was detected at a value lower than the LOQ. In conclusion, this multi-residue method can be used for screening through the detection and quantitation of residual multiclass veterinary drugs in feed samples. 相似文献
998.
Qingran Ding Xingyu Zhang Zheshuai Lin Zheyao Xiong Yusong Wang Xifa Long Sangen Zhao Maochun Hong Junhua Luo 《中国科学:化学(英文版)》2022,65(9):1710-1714
As structural variants of famous hexagonal tungsten bronzes, hexagonal tungsten oxides(HTO) represent an important family with fascinating functional properties, such as piezoelectric, ferroelectric, pyroelectric, and nonlinear optical(NLO) properties.However, none of them are transparent in the deep-UV spectral region, which limits their applications. Herein, we report the first HTO-type monofluorophosphate K3Sc3(PO4)(PO3F)2F5(I)... 相似文献
999.
1000.
Mi-Jin Kwon Ju-Woon Lee Kwan-Soo Kim Hao Chen Cheng-Bi Cui Gye Won Lee Young Ho Cho 《Molecules (Basel, Switzerland)》2022,27(14)
Alzheimer’s disease (AD) is an age-related neurodegenerative disorder characterized by cognitive deficits, which are accompanied by memory loss and cognitive disruption. Rhodiola sachalinensis (RSE) is a medicinal plant that has been used in northeastern Asia for various pharmacological activities. We attempted to carry out the bioconversion of RSE (Bio-RSE) using the mycelium of Bovista plumbe to obtain tyrosol-enriched Bio-RSE. The objective of this study was to investigate the effects of Bio-RSE on the activation of the cholinergic system and the inhibition of oxidative stress in mice with scopolamine (Sco)-induced memory impairment. Sco (1 mg/kg body weight, i.p.) impaired the mice’s performance on the Y-maze test, passive avoidance test, and water maze test. However, the number of abnormal behaviors was reduced in the groups supplemented with Bio-RSE. Bio-RSE treatment improved working memory and avoidance times against electronic shock, increased step-through latency, and reduced the time to reach the escape zone in the water maze test. Bio-RSE dramatically improved the cholinergic system by decreasing acetylcholinesterase activity and regulated oxidative stress by increasing antioxidant enzymes (superoxide dismutase (SOD) and catalase (CAT)). The reduction in nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling in the brain tissue due to scopolamine was restored by the administration of Bio-RSE. Bio-RSE also significantly decreased amyloid-beta 1–42 (Aβ1–42) and amyloid precursor protein (APP) expression. Moreover, the increased malondialdehyde (MDA) level and low total antioxidant capacity in Sco-treated mouse brains were reversed by Bio-RSE, and an increase in Nrf2 and HO-1 was also observed. In conclusion, Bio-RSE protected against Sco-induced cognitive impairment by activating Nrf2/HO-1 signaling and may be developed as a potential beneficial material for AD. 相似文献