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421.
Zainab H. Abdul-Hameed Nahed O. Bawakid Hajer S. Alorfi Tariq R. Sobahi Najla Ali Alburae Ahmed Abdel-Lateff Serag Eldin I. Elbehairi Mohammad Y. Alfaifi Nabil A. Alhakamy Walied M. Alarif 《Molecules (Basel, Switzerland)》2022,27(4)
Chromatographic investigation of the aerial parts of the Rhazya stricta (Apocynaceae) resulted in the isolation of two new monoterpene indole alkaloids, 6-nor-antirhine-N1-methyl (1) and razyamide (2), along with six known compounds, eburenine (3), epi-rhazyaminine (4), rhazizine (5), 20-epi-sitsirikine (6), antirhine (7), and 16-epi-stemmadenine-N-oxide (8). The chemical structures were established by various spectroscopic experiments. Compounds 1–8 exhibited cytotoxic effects against three cancer cells with IC50 values ranging between 5.1 ± 0.10 and 93.2 ± 9.73 µM against MCF-7; 5.1 ± 0.28 and 290.2 ± 7.50 µM against HepG2, and 3.1 ± 0.17 and 55.7 ± 4.29 µM against HeLa cells. Compound 2 showed the most potent cytotoxic effect against all cancer cell lines (MCF-7, HepG2 and HeLa with IC50 values = 5.1 ± 0.10, 5.1 ± 0.28, and 3.1 ± 0.17 µM, respectively). Furthermore, compound 2 revealed a significant increase in the apoptotic cell population of MCF-7, HepG2, and HeLa cells, with 31.4 ± 0.2%, 29.2 ± 0.5%, and 34.9 ± 0.6%, respectively. Compound 2 decreased the percentage of the phagocytic pathway on HepG2 cells by 15.0 ± 0.1%. These findings can explain the antiproliferative effect of compound 2. 相似文献
422.
Cong Tian Jielei Wang Ruoxuan Sun Tariq Ali Dr. Hongfei Wang Dr. Bin-Bin Xie Prof. Yijun Zhong Prof. Yong Hu 《Angewandte Chemie (International ed. in English)》2023,62(42):e202310970
The large-scale applicability of Zn-metal anodes is severely impeded by the issues such as the dendrite growth, complicated hydrogen evolution, and uncontrollable passivation reaction. Herein, a negatively charged carboxylated double-network hydrogel electrolyte (Gelatin/Sodium alginate-acetate, denoted as Gel/SA-acetate) has been developed to stabilize the interfacial electrochemistry, which restructures a type of Zn2+ ion solvent sheath optimized via a chain-liquid synergistic effect. New hydrogen bonds are reconstructed with water molecules by the zincophilic functional groups, and directional migration of hydrated Zn2+ ions is therefore induced. Concomitantly, the robust chemical bonding of such hydrogel layers to the Zn slab exhibits a desirable anti-catalytic effect, thereby greatly diminishing the water activity and eliminating side reactions. Subsequently, a symmetric cell using the Gel/SA-acetate electrolyte demonstrates a reversible plating/stripping performance for 1580 h, and an asymmetric cell reaches a state-of-the-art runtime of 5600 h with a high average Coulombic efficiency of 99.9 %. The resultant zinc ion hybrid capacitors deliver exceptional properties including the capacity retention of 98.5 % over 15000 cycles, energy density of 236.8 Wh kg−1, and high mechanical adaptability. This work is expected to pave a new avenue for the development of novel hydrogel electrolytes towards safe and stable Zn anodes. 相似文献
423.
424.
Ibrahim S. Al Nasr Markus Weise Waleed S. Koko Tariq A. Khan Rainer Schobert Bernhard Biersack 《应用有机金属化学》2023,37(1):e6952
Gold(I) complexes carrying imidazole-2-ylidene ligands and ferrocene substituents were prepared. Their activities against protozoal Leishmania major and Toxoplasma gondii parasites were analyzed. Certain gold(I) complexes with chlorido and 1,1′-bis(triphenylphosphino)ferrocene ligands revealed promising antiparasitic effects. The new chlorido complexes 5b and 5c showed high activities against T. gondii tachyzoites and L. major promastigotes while the new ferrocene-bridged bis-gold(I) complexes 8a and 8b were particularly active against L. major amastigotes and considerably selective as to toxicity results from Vero cells and macrophages. 相似文献
425.
Mathematical Analysis of SIR Epidemic Model with Piecewise Infection Rate and Control Strategies
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Yu Yang Tariq Q. S. Abdullah Gang Huang Yueping Dong 《Journal of Nonlinear Modeling and Analysis》2023,5(3):524-539
The limitation of contact between susceptible and infected individuals plays an important role in decreasing the transmission of infectious diseases. Prevention and control strategies contribute to minimizing the transmission rate. In this paper, we propose SIR epidemic model with delayed control strategies, in which delay describes the response and effect time. We study the dynamic properties of the epidemic model from three aspects: steady states, stability and bifurcation. By eliminating the existence of limit cycles, we establish the global stability of the endemic equilibrium, when the delay is ignored. Further, we find that the delayed effect on the infection rate does not affect the stability of the disease-free equilibrium, but it can destabilize the endemic equilibrium and bring Hopf bifurcation. Theoretical results show that the prevention and control strategies can effectively reduce the final number of infected individuals in the population. Numerical results corroborate the theoretical ones. 相似文献