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611.
612.
Su-A Lee Seong-Karp Hong Chang-Il Suh Mi-Hwa Oh Jeong-Ho Park Byoung-Wook Choi Seung-Won Park Soon-Young Paik 《Journal of microbiology (Seoul, Korea)》2010,48(2):249-252
The anti-HIV-1 activities of butanol, hexane, chloroform and water extracts from four widely used folk medicinal plants (Sophora flavescens, Tulipa edulis, Herba ephedra, and Pachyma hoelen Rumph) were evaluated in this study. The hexane extract of Pachyma hoelen Rumph, PH-4, showed effective inhibition against HIV-1. The 50% effective concentration (EC50) of PH-4 was 37.3 μg/ml in the p24 antigen assay and 36.8% in the HIV-1 recombinant RT activity test (at 200 μg/ml). In addition,
the PH-4 showed the protective effect on the infected MT-4 cells, with a 58.2% rate of protection. The 50% cytotoxic concentration
(CC50) of PH-4 was 100.6 μg/ml. These results suggest that PH-4 from Pachyma hoelen Rumph might be the candidate for the chemotherapy agent against HIV-1 infection with further study. 相似文献
613.
Sequences in the human immunodeficiency virus type 1 U3 region required for in vivo and in vitro integration. 总被引:5,自引:5,他引:0
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A series of mutants with alterations in the U3 region of the human immunodeficiency virus type 1 long terminal repeat were made, and the effects of these mutations were evaluated both in vitro and in vivo. When the subterminal 6 to 8 nucleotides of the U3 long terminal repeat were mutated, the resulting provirus was unable to efficiently replicate in vivo, and a mutant oligonucleotide which mimicked the mutation could not be efficiently cleaved but could be joined to target DNA by wild-type recombinant integrase protein in vitro. These results suggest that this region is important in the specific recognition of the viral DNA by the integrase protein. 相似文献
614.
Histone binding to isolated rat liver nuclei 总被引:1,自引:0,他引:1
Calf thymus histone H3 bound irreversibly to the isolated rat liver nuclei. The rate and extent of binding was a function of the incubation period and the concentration of both H3 and nuclei, but independent of the temperature. The binding was saturable and was inhibited by simultaneous presence of various histones. Approximately 94% of the bound H3 was associated with nuclear membrane fraction. 相似文献
615.
Summary During population genetic studies in Korea a new variant in the 6-phosphogluconate (6-PGD) system preliminary called 6-PGDKorea was observed. 相似文献
616.
617.
W K Paik J Farooqui A Gupta H T Smith F Millett 《European journal of biochemistry》1983,135(2):259-262
The present observations are the continuation of our earlier study on the physicochemical mechanism of protein-lysine methylation. In this paper the electrophoretic behaviour (pI values) of two chemically modified horse heart cytochromes c at lysine-72 with trifluoromethylphenylcarbamoyl (neutral group) or carboxydinitrophenyl (acidic group) is compared with the enzymatically methylated cytochrome c. The results indicate that although both chemically modified cytochromes c have lower pI values than the unmodified cytochrome c, the enzymatic methylation appears to be much more efficient in lowering the pI values of the protein than the chemical modification. Furthermore, the lowering of the pI value of cytochrome c by enzymatic methylation is highly dependent on the urea concentration. The presence of urea reduces the effect of methylation on the protein molecule and the difference in pI values virtually disappears with the increasing concentration of urea (6 M), which essentially disrupts the protein tertiary structure. 相似文献
618.
Sang Hoon Paik Yong Jae Kim Sang Kyul Han Jean Man Kim Jae Wook Huh Young In Park 《Biotechnology progress》2012,28(6):1517-1525
A formulation with stabilizers replacing albumin was developed for lyophilization of recombinant factor VIII (FVIII), GreenGene F (WHO INN: beroctocog alfa), to achieve stability and eliminate safety issues of blood‐derived albumin. L ‐Arginine (hydrophilic amino acid, positively charged side chain), L ‐glutamic acid (hydrophilic amino acid, negatively charged side chain), and L ‐isoleucine (hydrophobic amino acid, nonpolar) were selected as stabilizers, and the mixture of the three amino acids were optimized. The mixture had results comparative with albumin and other commonly used stabilizers showing good preservation of recombinant FVIII during lyophilization, robust stability with consistently high recovery of FVIIII, very low aggregate formation, and good storage stability without alterations in protein characteristics. In vivo test results showed that the efficacy was maintained and had no signs of toxicity. The study demonstrated that the three amino acid mixture acts as a good stabilizer for lyophilization of recombinant FVIII and as a safe excipient. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012 相似文献
619.
Minjin Kim Myunghee Cho Paik Jiyeong Jang Ying K. Cheung Joshua Willey Mitchell S. V. Elkind Ralph L. Sacco 《Biometrical journal. Biometrische Zeitschrift》2017,59(3):405-419
When analyzing time‐to‐event cohort data, two different ways of choosing a time scale have been discussed in the literature: time‐on‐study or age at onset of disease. One advantage of choosing the latter is interpretability of the hazard ratio as a function of age. To handle the analysis of age at onset in a principled manner, we present an analysis of the Cox Proportional Hazards model with time‐varying coefficient for left‐truncated and right‐censored data. In the analysis of Northern Manhattan Study (NOMAS) with age at onset of stroke as outcome, we demonstrate that well‐established risk factors may be important only around a certain age span and less established risk factors can have a strong effect in a certain age span. 相似文献