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1.
Anal Chem ; 96(25): 10111-10115, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38869290

ABSTRACT

The Si window is the most widely used internal reflection element (IRE) for electrochemical attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS), yet local chemical etching on Si by concentrated OH- anions bottlenecks the reliable application of this method in strong alkaline electrolytes. In this report, atomic layer deposition of a 25 nm nonconductive TiO2 barrier layer on the reflecting plane of a Si prism is demonstrated to address this challenge. In situ ATR-SEIRAS measurement on a Au film electrode with the Si/TiO2 composite IRE in 1 M NaOH reveals reversible global spectral features without spectral distortion at 1000-1300 cm-1, in stark contrast to those obtained with a bare Si window. By applying this structured ATR-SEIRAS, ethanol electrooxidation on a Pt/C catalyst in 1 and 5 M NaOH is explored, manifesting that such high pH values prevent the adsorption of as-formed acetate in the C2 pathway but not that of CO intermediate in the C1 pathway.

2.
ACS Appl Mater Interfaces ; 16(24): 31114-31125, 2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38857487

ABSTRACT

Albeit the undesirable attributes of NiOx, such as low conductivity, unmanageable defects, and redox reactions occurring at the perovskite/NiOx interface, which impede the progress in inverted perovskite solar cells (i-PSCs), it is the most favorable choice of technology for industrialization of PSCs. In this study, we propose a novel Ni vacancy defect modulate approach to leverage the conformal growth and surface self-limiting reaction characteristics of the atomic layer deposition (ALD)-fabricated NiOx by varying the O2 plasma injection time (tOE) to induce self-doping. Consequently, NiOx thin films with enhanced conductivity, an appropriate Ni3+/Ni2+ ratio, stable surface states, and ultrathinness are realized as hole-transporting layers (HTLs) in p-i-n PSCs. As a result of these improvements, ALD-NiOx-based devices exhibit the highest power conversion efficiency (PCE) of 19.86% and a fill factor (FF) of 81.86%. Notably, the optimal interfacial defects effectively suppressed the severe reaction between the perovskite and NiOx. This suppression is evidenced by the lowest decay rate observed in a harsh environment, lasting for 500 consecutive hours. The proposed approach introduces the possibility of a hierarchical distribution of defects and offers feasibility for the fabrication of large-area, uniform, and high-quality films.

3.
Am J Chin Med ; 51(8): 2095-2120, 2023.
Article in English | MEDLINE | ID: mdl-37865870

ABSTRACT

[Formula: see text]-Escin is an oleanane-type pentacyclic triterpenoid saponin extracted from the seeds of Aesculus hippocastanum (AH), which is more widely distributed. [Formula: see text]-Escin sodium has been approved by the American FDA for clinical usage. This paper is intended to summarize an updated and comprehensive review of the pharmacological activities, pharmacokinetic properties, toxicity, and analytical methods of [Formula: see text]-escin. Studies have shown that [Formula: see text]-escin has significant antitumor, antiviral, anti-inflammatory, and other activities alongside less adverse effects and higher safety than other compounds. The review shows that the pharmacological effects of [Formula: see text]-escin involve mechanisms such as ATM/[Formula: see text]H2AX, RhoA/Rock, GSK-3[Formula: see text]/[Formula: see text]-Catenin, HER2/HER3/Akt, and PI3K/Akt signaling pathways, and Cyclin A, p21[Formula: see text], survivin, Bcl-2, Mcl-1, Caspases, TGF-[Formula: see text], MMPs, and TNF-[Formula: see text] among other inflammatory factors. [Formula: see text]-Escin has significant cytotoxicity; the use of the chitosan/xanthan gum-based polyelectrolyte complexes PA1 and PC-11 to modify it not only to reduces its toxicity, but also improves its drug efficacy. Because of this, these compounds may become a new research hotspot. [Formula: see text]-Escin in vivo metabolism can be converted by the CYP1A2 enzyme in the intestinal flora to produce [Formula: see text]-escin, deacylated, deglycosylated, and 21[Formula: see text]-[Formula: see text]-crotonoyl-protoescin, and the binding rate of the plasma proteins is higher than 90%. These are mainly metabolized by the liver, kidneys, and other organs, and excreted in the form of urine and feces. The number of reports on the specific mediators of the metabolism of [Formula: see text]-escin and their mechanisms and metabolites is relatively small; furthermore, the results are vague. Therefore, a complete and in-depth exploration of the pharmacokinetic characteristics of [Formula: see text]-escin is needed to provide a more complete and effective theoretical reference for the study of its pharmacodynamic activity.


Subject(s)
Escin , Plant Extracts , Escin/pharmacology , Plant Extracts/pharmacology , Glycogen Synthase Kinase 3 , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt
4.
Front Pharmacol ; 14: 1164784, 2023.
Article in English | MEDLINE | ID: mdl-37649892

ABSTRACT

Enterovirus 71 (EV71) commonly causes symptoms such as hand, foot, and mouth disease (HFMD) in infants and children and may lead to neurological disease and even death in severe cases. Appropriate vaccines for the prevention of HFMD are available in the clinic; however, they present different and serious adverse effects that cannot guarantee compliance and efficacy. The purpose of this study was to analyze the potential mechanism of Bryum billardieri Schwaegr. (BBS) against EV71 and analyze its potential active components. A previous in vitro antiviral assay was used to determine the best extraction method for the active site of BBS against EV71, and the results showed that the antiviral activity of BBS was more pronounced in the fraction that was extracted by aqueous extraction and alcoholic precipitation and then obtained by purification on a silica gel column (dichloromethane:methanol = 0:100). In addition, the therapeutic effects of BBS on EV71-infected mice were further investigated by in vivo pharmacological experiments. BBS reduced the lung index, viral titer, and degree of EV71-induced lung, brain, and skeletal muscle damage. The mechanism of anti-EV71 activity of BBS was also investigated by using ELISA and qRT-PCR, and it was found that BBS exerted its action mainly by regulating the expression of TLR3, TLR4, TNF-α, IL-2, and IFN-γ by modulating the activation of NF-κB and JAK2/STAT1 signaling pathways. Finally, the chemical structures of the active monomers in BBS were determined by using UPLC-MS and NMR techniques. The study revealed that one of the monomers on which BBS exerts its antiviral activity is saponarin. In conclusion, the results of this study suggest that BBS is considered a natural anti-EV71 product with enormous potential, and saponarin would be its non-negligible active monomer.

5.
Appl Radiat Isot ; 198: 110852, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37210867

ABSTRACT

In this work, the independent fission cross-sections of U(n,f)238Xe135g and U(n,f)238Xe135m reactions induced by neutrons with the energies of 14.1 MeV, 14.5 MeV, and 14.7 MeV were measured by activation methods. The neutrons from T(d,n)He4 were used in the experiments and their energies were determined by the ratio of Zr(n,2n)90Zr89 and Nb(n,2n)93Nb92m reaction cross-sections. Aluminum films were chosen as reference samples to measure the neutron fluence relative to the cross section of the Al(n,α)27Na24 reaction. The effect of self-absorption, geometry, and cascade coincidence were also considered during the data analysis. Besides, the increase in the daughter nuclide yield due to the decay of the parent nuclides in the same decay chain was deducted. As a result, the independent fission cross-sections of the U(n,f)238Xe135g reaction are 2.54 ± 0.14 mb, 3.05 ± 0.19 mb and 2.94 ± 0.19 mb, while the cross-sections of U(n,f)238Xe135m reaction are 2.11 ± 0.16 mb, 2.47 ± 0.18 mb and 2.34 ± 0.21 mb for 14.1 MeV, 14.5 MeV and 14.7 MeV neutrons, respectively. This work provides experimental data for the database of nuclear fission reactions.


Subject(s)
Neutrons , Radioisotopes , Aluminum
6.
Front Genet ; 14: 1041103, 2023.
Article in English | MEDLINE | ID: mdl-36923796

ABSTRACT

Grasscutter (Thryonomys swinderianus) is a large-body old world rodent found in sub-Saharan Africa. The body size and the unique taste of the meat of this major crop pest have made it a target of intense hunting and a potential consideration as a micro-livestock. However, there is insufficient knowledge on the genetic diversity of its populations across African Guinean forests. Herein, we investigated the genetic diversity, population structures and evolutionary history of seven Nigerian wild grasscutter populations together with individuals from Cameroon, Republic of Benin, and Ghana, using five mitochondrial fragments, including D-loop and cytochrome b (CYTB). D-loop haplotype diversity ranged from 0.571 (± 0.149) in Republic of Benin to 0.921 (± 0.013) in Ghana. Within Nigeria, the haplotype diversity ranged from 0.659 (± 0.059) in Cross River to 0.837 (± 0.075) in Ondo subpopulation. The fixation index (FST), haplotype frequency distribution and analysis of molecular variance revealed varying levels of population structures across populations. No significant signature of population contraction was detected in the grasscutter populations. Evolutionary analyses of CYTB suggests that South African population might have diverged from other populations about 6.1 (2.6-10.18, 95% CI) MYA. Taken together, this study reveals the population status and evolutionary history of grasscutter populations in the region.

7.
Chin Herb Med ; 14(2): 310-316, 2022 Apr.
Article in English | MEDLINE | ID: mdl-36117666

ABSTRACT

Objective: The current investigation aimed to determine the appropriate dosage form by comparing solid dispersion and liposome to achieve the purpose of improving the solubility and bioavailability of linarin. Methods: Linarin solid dispersion (LSD) and linarin liposome (LL) were developed via the solvent method and the thin film hydration method respectively. The Transwell chamber model of Caco-2 cells was established to evaluate the absorption of drug. The pharmacokinetics of linarin, LSD and LL in rats after ig administration were carried out by high performance liquid chromatography (HPLC) method. Results: The solubility of LSD and LL was severally 3.29 times and 3.09 times than that of linarin. The permeation coefficients of LSD and LL were greater than 10-6, indicating that the absorption of LSD and LL were both better than linarin. The bioavailability of the LSD was 3.363 times higher than that of linarin, and the bioavailability of LL was 0.9886 times higher than that of linarin. Conclusion: The linarin was more suitable for making solid dispersion to enhance its solubility and bioavailability.

8.
Micron ; 157: 103263, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35390752

ABSTRACT

Precision elemental analysis by EELS at a nano-meter scale is a desirable goal for industrial application, as well as basic scientific research on advanced material analysis. However, sample thickness variation leads to a systematic error in element quantification due to electron plural scattering events and prevents it to be a useful quantitative analytic method. In this paper, we compared three methods to minimize thickness effect: Fourier-log deconvolution, Jump ratio, and Si K-edge by quantifying the N/Si ratio versus different thickness on a standard Si3N4 crystal sample. The results indicated that Jump ratio method exceeded other two methods owing to its higher accuracy, short data acquisition time as well as minimum requirement for spectroscopy instrument. The jump ratio method was applied to calculate N/Si ratio in storage nitride layer of 3D NAND trench wafer and blanket wafer, both illustrated that the jump ratio method successfully corrected the thickness effect on EELS composition quantification and largely reduced the relative error compared with the non-corrected result.

9.
Molecules ; 28(1)2022 Dec 23.
Article in English | MEDLINE | ID: mdl-36615326

ABSTRACT

Matricaria chamomilla L. (MC) and Chamaemelum nobile (L.) All. (CN) are two varieties of Chamomile. These herbs have been used for thousands of years in Greece, Rome and ancient Egypt. Chamomile has been used for the treatment of stomach problems, cramps, dermatitis, and minor infections. The purpose of this study was to introduce the botanical characteristics and geographical distribution, traditional uses, chemical constituents, pharmacological activities, toxicity studies and quality control studies, and lay a theoretical foundation for the rational development and utilization of chamomile. This review powered that chemical constituents include flavonoids, coumarins, volatile oils, terpenes, organic acids, polysaccharides, and others. These compounds possess anticancer, anti-infective, anti-inflammatory, antithrombotic, antioxidant, hypolipidaemic, hypoglycaemic, antihypertensive, antidepressant, neuroprotective activities, among others. Chamomile is a widely used herb in traditional medicine. It brings great economic value due to its numerous pharmacological effects and traditional uses. However, more toxicity tests should be carried out to confirm its safety. There is need for further research to provide concrete scientific evidence and validate its medicinal properties.


Subject(s)
Chamomile , Oils, Volatile , Plant Extracts/chemistry , Oils, Volatile/pharmacology , Oils, Volatile/chemistry , Terpenes , Quality Control , Medicine, Traditional
10.
Mitochondrial DNA B Resour ; 6(7): 2092-2094, 2021 Jun 22.
Article in English | MEDLINE | ID: mdl-34212107

ABSTRACT

Thrips hawaiiensis (Morgan) (Thysanoptera: Thripidae) is a common Thysanoptera insect widely distributed in Asia and the Pacific, it damages various plants. In this study the complete mitochondrial genome of T. hawaiiensis was sequenced and characterized by using next-generation sequencing technique. The total length of the complete genome is 15,357 bp and A + T content of 77.8% (GeneBank accession No. MW582621). The T. hawaiiensis mitochondrial genome consists of 13 protein-coding genes (PCGs), 2 ribosomal RNA genes, 22 transfer RNA genes (tRNAs) and 2 non-coding control regions (Dloop region). According to previous studies, only a few complete mitochondrial genomes from Order Thysanoptera have been reported. Thus, T. hawaiiensis complete mitochondrial genome sequence reported will provide molecular information for mitochondrial genome research on Thysanoptera.

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