查找使用阿拉丁产品的科研文献

Design, synthesis and evaluation of 2-arylethenyl-N-methylquinolinium derivatives as effective multifunctional agents for Alzheimer's disease treatment

Chun-Li Xia,Ning Wang,Qian-Liang Guo,Zhen-Quan Liu,Jia-Qiang Wu,Shi-Liang Huang,Tian-Miao Ou,Jia-Heng Tan,Hong-Gen Wang,Ding Li,Zhi-Shu Huang

A series of 2-arylethenyl- N -methylquinolinium derivatives were designed and synthesized based on our previous research of 2-arylethenylquinoline analogues as multifunctional agents for the treatment of Alzheimer's disease (AD) (Eur. J. Med. Chem. 2015, 89, 349–361). The results of in vitro biological activity evaluation, including β-amyloid (Aβ) aggregation inhibition, cholinesterase inhibition, and antioxidant activity , showed that introduction of N -methyl in quinoline ring significantly improved the anti-AD potential of compounds. The optimal compound, compound a12 , dramatically attenuated the cell death of glutamate-induced HT22 cells by preventing the generation of ROS and increasing the level of GSH. Most importantly, intragastric administration of a12 •HAc was well tolerated at doses up to 2000 mg/kg and could traverse blood-brain barrier.

A nonenzymatic electrochemical nitrite sensor based on Pt nanoparticles loaded Ni(OH)2/multi-walled carbon nanotubes nanocomposites

Qinglin Sheng,Duo Liu,Jianbin Zheng

In this paper, a sensitive novel non-enzymatic nitrite electrochemical sensor based on Pt nanoparticles loaded Ni(OH) 2 /Multi-Walled Carbon Nanotubes nanocomposites (Pt/Ni(OH) 2 /MWCNTs) was described. The composition and morphology of the Pt/Ni(OH) 2 /MWCNTs were characterized by transmission electron microscope and investigated energy dispersive X-ray spectra respectively. Results showed that the Pt nanoparticles could be anchored on the surface of the Ni(OH) 2 /MWCNTs uniformly through a simple reduction process. The electrochemical investigation of the sensor revealed that the Pt/Ni(OH) 2 /MWCNTs exhibited remarkable electrocatalytic performance toward nitrite oxidation , with a sensitivity of 145   μA   mM −   1   cm −   2 and a low detection limit of 0.13   mM. Moreover, the obtained Pt/Ni(OH) 2 /MWCNTs modified GCE with excellent reproducibility and selectivity also allows for practical application. It is expected that the combination of noble metal with Ni(OH) 2 /MWCNTs could be expanded to enhance the catalytic performances of nanocomposites and used for the construction of high-sensitive electrochemical sensors.

Developmental cardiotoxicity of 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (DCOIT) in marine medaka (Oryzias melastigma)

Mengyuan Liu,Jing Li,Jiali Li,Bingsheng Zhou,Paul K.S. Lam,Chenyan Hu,Lianguo Chen

The application of 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (DCOIT) as an antifouling biocide causes high toxicity to non-target marine organisms. To examine the developmental cardiotoxicity and mechanisms of DCOIT, we concurrently performed sub-chronic exposure and life-cycle exposure experiments using marine medaka embryos. After sub-chronic exposure to DCOIT at 1, 3, 10, and 33 μg/L, cardiac defects were caused by upregulation of cardiac gene transcriptions, decreasing heart size, and accelerating heartbeat. Hyperthyroidism in medaka larvae was identified as the cause of developmental cardiotoxicity of DCOIT sub-chronic exposure. In addition, parental life-cycle exposure to 1, 3, and 10 μg/L DCOIT led to transgenerational impairment of cardiogenesis in offspring medaka. A crossbreeding strategy discriminated a concentration-dependent mechanism of transgenerational cardiotoxicity. At 1 μg/L, the DCOIT-exposed female parent transferred a significantly higher amount of triiodothyronine (T3) hormone to offspring, corresponding to an accelerated heart rate. However, DCOIT at higher exposure concentrations modified the methylome imprinting in larval offspring, which was associated with cardiac dysfunction. Overall, the findings provide novel insights into the developmental cardiotoxicity of DCOIT. The high risks of DCOIT—even at environmentally realistic concentrations—raise concerns about its applicability as an antifoulant in a marine environment.

Hydrogel SERS chip with strong localized surface plasmon resonance for sensitive and rapid detection of T-2 toxin

Mingming Chen,Bihang Su,Huiying Wu,Yawen Dai,Tianwen Chen,Fengfu Fu,Zhenyu Lin,Yongqiang Dong

T-2 toxin is one of the naturally dangerous food contaminants, which is harmful to people and animals. Because of its strong toxicity and wide distribution, it is vital to develop a rapid and effective method for the detection of T-2 toxin. Herein, an excellent hydrogel surface-enhanced Raman scattering (SERS) chip is constructed for developing a novel SERS sensor to detect T-2 toxin using a portable Raman spectrometer. The SERS chip is prepared by in-situ Ca 2+ -mediated assembly of silver nanoparticles (AgNPs) in PVA solution, followed by a physical crosslinking possess. The assembled AgNPs produces a strong localized surface plasmon resonance (LSPR) at around 532 nm, which enables the high activity of SERS chip under the irradiation of 532 nm laser. Additionally, the unique structure of hydrogel makes the obtained chip show excellent reliability and anti-interference ability in detection. As a result, the developed SERS sensor shows many obvious advantageous including free of complex sample pretreatment (only a simple extraction), fast response (5 min), low limit of detection (0.41 ppb), wide detection range (1–10000 ppb), good recoveries (90.26–101.81 %) and relative standard deviations (2.8–6.7 %). Therefore, this SERS sensor provides a promising choice for rapid scanning and sensitive detection of trace T-2 toxin in complex matrices.

Chiral metal–organic framework [Zn2(D-Cam)2(4,4′-bpy)]n@SiO2 core–shell composite for HPLC separation

Cai-Fang Liu,Xiao-Yan Ran,Cheng Liu,Yu-lan Zhu,Yan-Rui Lu,Yu-Ping Yang,Bang-Jin Wang,Jun-Hui Zhang,Sheng-Ming Xie,Li-Ming Yuan:

Chiral metal–organic frameworks, an emerging type of chiral porous materials, possess many outstanding characteristics such as high surface area, tunable pore sizes, and good chemical stability. Herein, we prepared a chiral [Zn 2 (D-Cam) 2 (4,4′-bpy)] n @SiO 2 core–shell composite on the SiO 2 -NH 2 microspheres by an in-situ growth method. The prepared [Zn 2 (D-Cam) 2 (4,4′-bpy)] n @SiO 2 -packed column exhibited high-resolution separation of racemic compounds and positional isomers at a low column backpressure (9–12 bar). Twelve pairs of enantiomers including alcohols, amines, epoxides, ketones, and esters were well resolved with sharp peak shapes on the [Zn 2 (D-Cam) 2 (4,4́-bpy)] n @SiO 2 chromatographic column. Compared the separation performance of [Zn 2 (D-Cam) 2 (4,4́-bpy)] n @SiO 2 -packed column and two chromatographic columns (commercial Chiralpak AD-H column and as-prepared SiO 2 -NH 2 column), the [Zn 2 (D-Cam) 2 (4,4′-bpy)] n -packed column and the commercial Chiralpak AD-H column have a good complementarity in chiral separation, and it also offered better separation performance compared to the SiO 2 -NH 2 column for separating positional isomers. The effects of column temperature and analyte mass on the HPLC separation were investigated. Additionally, the [Zn 2 (D-Cam) 2 (4,4́-bpy)] n @SiO 2 packed column has good repeatability and stability for HPLC separation of enantiomers and positional isomers. The relatvive standard deviations (RSDs) for repeated separations of 2,2,2-trifluoro-1-(9-anthryl)ethanol and o , m , p -bromoaniline were less than 0.8 % and 1.2 % for the retention time and peak area, respectively. After continuous use for one month, the RSDs for the retention time and peak area of them were in the range of 1.1–1.3 % and 1.5–1.8 % (inter-day and intra-day, n = 5), respectively. This work also indicates that the chiral MOFs@SiO 2 composites are promising for HPLC separation.

Improved 2∼5 μm mid-infrared fluorescence through energy transfer processes in Er3+/Ho3+ co-doped fluoride glasses

Chuncheng Zhang,Chaomin Zhang,Chao Yun

In this paper, Er 3+ /Ho 3+ co-doped fluoride glasses were prepared by the high temperature melt-quenching technique. Pumped by the 980 nm LD , as a result of the emission spectra overlapping of Er 3+ and Ho 3+ ions, a broadband mid-infrared emission band from 2530 to 2950 nm with a full width at half maximum of the synthetic fluoride glasses near 231 nm was obtained, which exist latent application in wide band tunable mid-infrared fiber laser. Furthermore, the intense 4.1 μm mid-infrared fluorescence (3600–4400 nm) was obtained and the FWHM was 320 nm. The up-conversion emission peaks around 525, 546 and 660 nm, near-infrared emissions at 1.2 and 1.5 μm together with mid-infrared fluorescence around 2.0 μm was observed in Er 3+ /Ho 3+ co-doped fluoride glass. Moreover, the relevant energy transfer processes were discussed in detail based on the emission spectrum and the energy level transition processes. The results indicate that the fabricated Er 3+ /Ho 3+ co-doped fluoride glasses exist prominent emission features for fiber laser gain medium.

Tailoring flower-like Zn(OH)2 nanoarchitectures and stearic acid on cellulosic fibers for structurally robust superhydrophobic surface

Chao Li,Tongtong Yun,Gaofeng Pan,Yehan Tao,Jie Lu,Jian Du,Haisong Wang

Structurally robust nanostructures on the surface of matrix highly determine the durability of superhydrophobic surface of cellulosic materials . Traditionally, the hydrophobic inorganic-organic nanocomposites were physically coated on the surface of cellulose fibers , whereas the nanocomposite was easy to fall off under external force due to the weak interfacial interaction between inorganic materials and cellulose, restricting their practical application. In this work, a sort of structurally stable superhydrophobic cellulosic materials was elaborately designed by successive in situ synthesis of Zn(OH) 2 nanoarchitectures and coating stearic acid (STA). The unique flower-like micro/nano structures as well as the presence of hydrophobic STA imparted the cellulosic materials with superhydrophobic behavior and the optimized water contact angle of synthesized STA@Zn(OH) 2 /paper nanocomposite was enhanced to 171°. Moreover, the resultant cellulosic nanocomposite also possesses excellent structural stability without STA and Zn(OH) 2 fall off as well as hydrophobicity reduction after bending 100 times. Compared to bare filter paper, both tensile stress and elongation at break of optimized flower-like nanocomposite reached 14.04 MPa and 25.24% with 109.6% and 323.5% improvement, respectively. Furthermore, such superhydrophobic cellulose-based material also presented excellent anti-fouling and antibacterial performances. This work proposed a facial and efficient strategy to construct structurally stable superhydrophobic cellulose-based materials, displaying great potential application in food packaging and outdoor anti-fouling fields.

Modulating surface electron density of hydrophilic/high-conductive MXene/Ni(OH)2/NF heterostructures for efficient asymmetric supercapacitors

Xinyu Liu,Qianqian Fu,Zhichao Li,Hui Wang,Jianwei Ren

To address the growing demand for efficient and stable energy storage in the context of green energy, in this study, an acid etching method was employed to in-situ grow Ni(OH) 2 nanosheet arrays on a nickel foam (NF) substrate. Subsequently, negatively charged Ti 3 C 2 T x MXene nanosheets were electrophoretically deposited onto the Ni(OH) 2 /NF surface to result in a MXene/Ni(OH) 2 /NF composite electrode material. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations revealed the homogeneous dispersion distribution of nanosheets on the material surface. The composite material exhibited high electrical conductivity and good hydrophilicity by rapid water infiltration within 150 ms. Furthermore, the Motte-Schottky effect establishes a distinctive pathway for electron transfer , which leads to the creation of electron vacancies or ‘holes’ on the MXene surface. This phenomenon significantly boosts MXene's electrochemical activity and enhances its affinity for OH − ions in the electrolyte, which consequently improves the performance of electrochemical capacitors . Electrochemical tests verified that the prepared MXene/Ni(OH) 2 /NF electrode displayed an areal specific capacitance of 0.223 mAh cm −2 at a current density of 1 mA cm −2 . The electrode displayed excellent rate performance with a capacity retention rate of 71 % when the current density was increased by five times. In addition, the assembled asymmetric capacitor with MXene/Ni(OH) 2 /NF electrode demonstrated an excellent cycling stability with only a 16.38 % capacity loss after 5000 cycles. It also exhibited the remarkable specific capacitance and long-term stability by achieving a high energy density of 43.68 Wh kg −1 and a power density of 424.96 W kg −1 . These results highlight the electrode's exceptional performance in terms of energy storage and power delivery.

Controlled SPION-Exosomes Loaded with Quercetin Preserves Pancreatic Beta Cell Survival and Function in Type 2 Diabetes Mellitus

Manjiao Zhuang,Lei Rao,Yadi Chen,Shangying Xiao,Haishan Xia,Jiangyong Yang,Xiaohua Lv,Dongyun Qin,Chunjie Zhu

Deep Eutectic Solvents Based on L-Arginine and 2-Hydroxypropyl-β-Cyclodextrin for Drug Carrier and Penetration Enhancement

Lv Jianhua,Wu Pan,Fang Yaru,Zhang Wenchang,Liu Dongwen,Wu Mi,Shang Lei,Li Huaiguo,Zhao Yan

By selecting L-arginine as the hydrogen bond acceptor (HBA) and 2-hydroxypropyl-β-cyclodextrin (2HPβCD) as the hydrogen bond donor (HBD), deep eutectic solvents (DESs) with various water content were prepared at the 4:1 mass ratio of L-arginine to 2HPβCD with 40 to 60% of water, and were studied for its application in transdermal drug delivery system (TDDS). The hydrogen bond networks and internal chemistry structures of the DESs were measured by attenuated total reflection Fourier transform infrared (ATR-FTIR) and 1 H-nuclear magnetic resonance spectroscopy ( 1 H-NMR), which demonstrated the successful synthesis of DESs. The viscosity of DES was decreased from 10,324.9 to 3219.6 mPa s, while glass transition temperature (Tg) of the DESs was increased from − 60.8 to − 51.4 °C, as the added water was increased from 45 to 60%. The solubility of ibuprofen, norfloxacin, and nateglinide in DES with 45% of water were increased by 79.3, 44.1, and 3.2 times higher than that in water, respectively. The vitro study of transdermal absorption of lidocaine in DESs showed that the cumulative amounts of lidocaine reached 252.4 µg/cm 2 , 226.1 µg/cm 2 , and 286.1 µg/cm 2 at 8 h for DESs with 45%, 50%, and 60% of water, respectively. The permeation mechanism of DES with lower content of water (45%) was mainly by changing the fluidization of lipids, while changing the secondary structure of keratin in stratum corneum (SC) at higher water content (50% and 60%). These nonirritant and viscous fluid like DESs with good drug solubility and permeation enhancing effects have broad application prospect in the field of drug solubilization and transdermal drug delivery system. Graphical Abstract

CircMEF2C(2, 3) modulates proliferation and adipogenesis of porcine intramuscular preadipocytes by miR-383/671-3p/MEF2C axis

Xiaoyin Rong,Ruixiao Li,Tianye Gong,Haonan Li,Xiaolei Zhao,Guoqing Cao,Meng Li,Bugao Li,Yang Yang,Xiaohong Guo

Circular RNA is a special category of non-coding RNA that has emerged as epigenetic regulator of adipose tissue development. However, the mechanism governing intramuscular adipogenesis of circRNA remains largely uncharted. In this study, circMEF2C(2, 3), looped by MEF2C exons 2 and 3, was identified from the pig MEF2C gene. Expression of circMEF2C(2, 3) is upregulated in early stage of intramuscular adipogenesis and muscular tissue of lean pigs (DLY pig). Subsequently, overexpression or knockdown of circMEF2C(2, 3) reflected that it participates in promoting proliferation and inhibiting adipogenic differentiation in porcine intramuscular preadipocytes and murine C3H10T1/2 cells. Mechanically, circMEF2C(2, 3) competitively combined with miR-383 and miR-671-3p to the 3′-UTR of MEF2C , which maintains MEF2C expression in regulating proliferation and adipogenesis. In summary, circMEF2C(2, 3) is a key regulator in the proliferation and adipogenic differentiation of intramuscular adipogenesis, suggesting its potential as a multi-target strategy for adipose development and associated diseases.

Synthesis and upconversion luminescent properties of Bi2MoO6:20%Yb3+, 2%Er3+ hollow microsphere with different W6+ ions doping

Wen Ge,Kong Liu,Peizhi Yang,Shukang Deng,Lanxian Shen

In this work, W 6+ ions doped Bi 2 MoO 6 :20%Yb 3+ , 2%Er 3+ samples were successfully synthesized by a facile and modified hydrothermal method . The main morphology of Bi 2 MoO 6 samples were hollow microsphere structure assembled by nanosheets . The particle size was slightly increased as enhancing W 6+ ions doping concentration to 5%, then decreased as the doping concentration increased. Besides, doping W 6+ ions can increase the band gap of products from 2.65 ​eV to 2.71eV. The upconversion emission intensity of all samples was strongly influenced by the W 6+ ions doping concentration. The luminescent intensity enhanced with the doping concentration increasing up to 3%, then decreased when the W 6+ ions concentration further increased. Moreover, the intensity of red emission increased by a large margin than that of green-light region. Besides, the lifetime of 4 F 9/2 states of Er 3+ ions for Bi 2 MoO 6 :20%Yb 3+ , 2%Er 3+ , 3%W 6+ (τ 655  ​= ​583.64 ​μs) had significant longer lifetime relative to the Bi 2 MoO 6 :20%Yb 3+ , 2%Er 3+ (τ 655  ​= ​70.29 ​μs).