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81.
The mass cultivation of Ecklonia stolonifera Okamura was studied as a possible summer feed for the abalone industry in Korea for the period between August and November
when Undaria and Laminaria are not available. Experiments were conducted to investigate the optimal conditions for artificial seed production and mass
cultivation of this species. Seedlings of E. stolonifera were reared in an indoor tank for 60 days until they were around 500 μm in length. Following indoor tank culture, the seedlings
were transferred in situ to a nursery culture area for 2 months, before begin transferred to the main grow-out area. The maximum growth and development
of young thalli in nursery culture area occurred at 2 m depth, whilst maximum growth of thalli in the main culture area occured
at 1.5 m depth. Production of E. stolonifera was between 3 and 9 kg wet wt. m−1 in the first year of culture after seeding and 12 to 13 kg wet wt. m−1 in the second year of culture, after management (depth control and fouling organism removal, etc.) of the holdfast. The relationship
between optimal water depth for culture and underwater irradiance during the E. stolonifera cultivation was defined as: y = −0.331x + 8.198 (r
2 = 0.9903). The growth rates achieved in this trial indicate that E. stolonifera cultures could produce sufficient biomass to supply summer feed for the Korean abalone industry. 相似文献
82.
Lee WS Lee DW Baek YI An S An SJ Cho KH Choi YK Kim HC Park HY Bae KH Jeong TS 《Bioorganic & medicinal chemistry letters》2004,14(12):3109-3112
The sesquineolignan, saucerneol B (1), and dineolignans, manassantin A (2), and manassantin B (3), were isolated from the methanol extracts of Saururus chinensis root and elucidated by their spectroscopic data analysis. Compounds 1-3 inhibited hACAT-1 and hACAT-2 with IC(50) values of 43.0 and 124.0 microM for 1, of 39.0 and 8.0 microM for 2, of 82.0 microM and only 32% inhibition at 1mM for 3, respectively. The EtOAc-soluble fraction, which contained compounds 1-3, of methanol extracts of S. chinensis exhibited strong cholesterol-lowering effect in high cholesterol-fed mice. 相似文献
83.
Tatsuya Maehigashi Seohyun Ahn Uk-Il Kim Jared Lindenberger Adrian Oo Pratibha C. Koneru Bijan Mahboubi Alan N. Engelman Mamuka Kvaratskhelia Kyungjin Kim Baek Kim 《PLoS pathogens》2021,17(7)
Allosteric integrase inhibitors (ALLINIs) are a class of experimental anti-HIV agents that target the noncatalytic sites of the viral integrase (IN) and interfere with the IN-viral RNA interaction during viral maturation. Here, we report a highly potent and safe pyrrolopyridine-based ALLINI, STP0404, displaying picomolar IC50 in human PBMCs with a >24,000 therapeutic index against HIV-1. X-ray structural and biochemical analyses revealed that STP0404 binds to the host LEDGF/p75 protein binding pocket of the IN dimer, which induces aberrant IN oligomerization and blocks the IN-RNA interaction. Consequently, STP0404 inhibits proper localization of HIV-1 RNA genomes in viral particles during viral maturation. Y99H and A128T mutations at the LEDGF/p75 binding pocket render resistance to STP0404. Extensive in vivo pharmacological and toxicity investigations demonstrate that STP0404 harbors outstanding therapeutic and safety properties. Overall, STP0404 is a potent and first-in-class ALLINI that targets LEDGF/p75 binding site and has advanced to a human trial. 相似文献
84.
85.
Feasibility of supercritical CO₂ treatment for controlling biofouling in the reverse osmosis process
Physical cleaning and/or chemical cleaning have been generally used to control biofouling in the reverse osmosis (RO) process. However, conventional membrane cleaning methods to control biofouling are limited due to the generation of by-products and the potential for damage to the RO membranes. In this study, supercritical carbon dioxide (SC CO(2)) treatment, an environmentally friendly technique, was introduced to control biofouling in the RO process. SC CO(2) (100 bar at 35°C) treatment was performed after biofouling was induced on a commercial RO membrane using Pseudomonas aeruginosa PA01 GFP as a model bacterial strain. P. aeruginosa PA01 GFP biofilm cells were reduced on the RO membrane by >8 log within 30 min, and the permeate flux was sufficiently recovered in a laboratory-scale RO membrane system without any significant damage to the RO membrane. These results suggest that SC CO(2) treatment is a promising alternative membrane cleaning technique for biofouling in the RO process. 相似文献
86.
Tissue expression and cellular localization of phospholipid hydroperoxide glutathione peroxidase (PHGPx) mRNA in male mice 总被引:1,自引:0,他引:1
Baek IJ Seo DS Yon JM Lee SR Jin Y Nahm SS Jeong JH Choo YK Kang JK Lee BJ Yun YW Nam SY 《Journal of molecular histology》2007,38(3):237-244
Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is an ubiquitous antioxidant enzyme, but the exact expression pattern
in mammalian tissues is still unknown. The expression and cellular localization of PHGPx mRNA were examined in male mice using
real time-polymerase chain reaction and in situ hybridization techniques. The rank order of PHGPx mRNA expression across tissues exhibiting substantial levels of expression
was:testes ≫ heart > cerebrum ≥ ileum > stomach = liver = jejunum ≥ epididymis. In testes, PHGPx mRNA was highly expressed
in spermiogenic cells and Leydig cells. The signal was also expressed in the molecular layer, Purkinje cell layer, and white
matter of cerebellum, the pituicytes of neurohypophysis, the parafollicular cells and follicular basement membrane of thyroid,
the exocrine portion of pancreas, the tubular epithelium of kidney, the smooth muscle cells of arteries, and the red pulp
of spleen. In the gastrointestinal tract, PHGPx mRNA expression was mainly observed in the keratinized surface epithelium
of forestomach, the submucosal glands and serosa layers, and further the Paneth cells of intestines. PHGPx mRNA appeared to
be ubiquitously expressed in the parenchyma of heart, liver, and lung. These results indicate that PHGPx exhibits a cell-
and tissue-specific expression pattern in mice. 相似文献
87.
88.
S H Baek Y J Yoo K Tanaka C H Chung 《Biochemical and biophysical research communications》1999,264(1):235-240
A full-length cDNA encoding ubiquitin C-terminal hydrolase-6 (UCH-6) was isolated from the chick skeletal muscle cDNA library. The sequence of two peptides generated from purified UCH-6 matched perfectly with the predicted amino acid sequence. Nucleotide sequence analysis of the cDNA containing an open reading frame of 690 base pairs revealed that the protease consists of 230 residues with a calculated molecular mass of 26,315 Da. UCH-6 belonged to members of the UCH family containing highly conserved Cys, His, and Asp domains and showed 86% amino acid identity to human UCH-L3. Interestingly, most tissues examined contained significant amounts of UCH-6 mRNA, while human UCH-L3 is expressed only in the brain, lungs, and red cells. Moreover, UCH-6, unlike other UCH family enzymes including UCH-L3, could release free ubiquitin from ubiquitin-beta-galactosidase fusion proteins both in vivo and in vitro. The ubiquitous expression pattern and unusual substrate specificity of UCH-6 suggest that the enzyme may represent a distinct subfamily of UCH-L3. 相似文献
89.
It has been suggested that infectious entry of rubella virus (RV) is conducted by receptor mediated endocytosis. To explore the cellular entry mechanism of RV, inhibitory effects of drugs affecting various endocytic pathways on RV entry into VeroE6 cells were analyzed. Results showed that RV infectious entry into VeroE6 cells is mediated by clathrin-dependent endocytosis and not by caveolae-mediated endocytosis. Moreover, chemical inhibition of macropinocytosis such as treatments of amiloride, actin and microtubule-disrupting drug significantly reduced RV infection. Considering that macropinocytosis is inducible endocytosis by cellular stimulations, clathrin-mediated endocytosis is likely to be a major route of RV infectious entry. 相似文献
90.