The Mechanism of Inhibition of Caloric Nystagmus by Eye Closure

Author(s):  
S. Takemori ◽  
H. Moriyama ◽  
G. Totsuka
2020 ◽  
Vol 16 (4) ◽  
pp. 531-543
Author(s):  
Shaheen Faizi ◽  
Tahira Sarfaraz ◽  
Saima Sumbul ◽  
Almas Jabeen ◽  
Sobia A. Halim ◽  
...  

Background: In continuation of our work on Mannich reaction on 8-hydroxyquinoline, fifteen different combinations of aromatic aldehydes and aniline were subjected to Mannich reaction from which twelve products (eight Mannich bases, two imines and two intramolecularly cyclized products with benzofuranone skeleton) were obtained. Among them six compounds (1, 2, 6, 8, 9 and 12) are the new compounds. The structures of the compounds were characterized by UV, IR, MS and 1H NMR. Method: The compounds were tested for the inhibition of pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and Interleukin-1β (IL-1β) at a concentration of 25 µg/mL. The cytokines were produced by THP-1 cells differentiated with PMA for 24hrs and stimulated with LPS for 4 hrs and supernatant were analyzed through ELISA technique. Results and Discussion: Compounds 1-5, 8 and 9 inhibited the production of TNF-α and IL-1β. Compounds 1, 3, and 8 exerted potent inhibitions of TNF-α with 71%, 71%, and 83% inhibition, respectively. Compounds 1 and 8 significantly inhibited the production of IL-1β with 64% and 78% inhibition, respectively. Conclusion: Compounds 1 and 8 significantly inhibited the production of IL-1β with 64% and 78% inhibition, respectively. Notably compound 8 showed the most potent inhibition of these cytokines. Additionally, the effect of compounds on viability of THP-1 cells was also evaluated. Moreover, molecular docking was carried out to study the mechanism of inhibition of TNF-α production.


1980 ◽  
Vol 45 (2) ◽  
pp. 641-652
Author(s):  
Petr Zbořil

Semiquinone is an intermediary product of the oxidation of daphnetin (7,8-dihydroxycoumarin) and esculetin (6,7-dihydroxycoumarin) by diphenol oxidase; its concentration rapidly decreases. When the oxidation is effected by ferricytochrome c, the concentration of the semiquinone remains practically constant for a long period. Similarly, the ability of the products of daphnetin oxidation by diphenol oxidase to inhibit succinate oxidase activity in mitochondrial fragments rapidly decreases with time; the decrease is considerably slower in the case of cytochrome c. The inhibitory activity of the product decreases with time also during esculetin oxidation by ferricyanide. This indicates that the inhibitory effects must be ascribed predominantly to the semiquinone, the quinone is less efficient. The inhibition of succinate oxidase or succinate dehydrogenase was strongly decreased when the enzyme preparation of Keilin and Hartree was incubated with esculetin and ferricyanide in the presence of KCN or under anaerobic conditions. This demonstrates that the reaction of the inhibitor with the enzyme either involves subsequent oxidations or that the inhibitor preferentially reacts with the oxidized form of the sensitive component of the respiratory chain. The second alternative is very little probable since there is no correlation between the degree of inhibition and the binding of the inhibitor to mitochondrial fragments.


1989 ◽  
Vol 37 (10) ◽  
pp. 2855-2857 ◽  
Author(s):  
Shigeharu NOCHI ◽  
Naoyuki SHIMOMURA ◽  
Teiichi HATTORI ◽  
Tadashi SATO ◽  
Yasuo MIYAKE ◽  
...  

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Yingchang Li ◽  
Fengxia Du ◽  
Suzhen Song ◽  
Shuangyan Li ◽  
Xianqing Yang ◽  
...  

AbstractThe effects of chlorogenic acid and quercetin-3-D-galactoside on the decomposition of trimethylamine oxide (TMAO) in squid extract and the main mechanism of inhibition of thermal decomposition were studied. The results indicated that chlorogenic acid and quercetin-3-D-galactoside could inhibit decomposition of TMAO in squid extract. The amount of TMAO was increased by 11.79 and 15.76% in squid extract treated with chlorogenic acid and quercetin-3-D-galactoside from 0 and 2.5 g/L, respectively. The contents of trimethylamine (TMA), dimethylamine (DMA), and formaldehyde (FA) were significantly decreased with increasing contents of chlorogenic acid and quercetin-3-D-galactoside. There were many free radicals in squid extract at high temperatures; however, the free radical signals were weakened after the addition of chlorogenic acid and quercetin-3-D-galactoside therein. This implied that chlorogenic acid and quercetin-3-D-galactoside could inhibit the thermal decomposition of TMAO in squid extract, which was associated with the scavenging of their free radicals. This result provides a theoretical basis for the development and utilization of blueberry leaf extract as an efficient FA inhibitor for aquatic products.


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