http://hdl.handle.net/10027/8171 Fri, 24 May 2013 17:01:17 GMT 2013-05-24T17:01:17Z http://hdl.handle.net/10027/8732 Phenolic Compounds from Eurycorymbus cavaleriei Hea, Yi; Zhang, Li; Zhao, Ming; Tsai, Sam-Hip; Zong, Yuying; Che, Chun-Tao Three new phenolic compounds, eurycorymboside A (1), eurycorymboside B (6), and eurycorymbic acid (8) were isolated from the stem part of Eurycorymbus cavaleriei (Sapindaceae), along with five known phenolic compounds, glucosyringic acid (2), vanillic acid 4-O-β-D-glucoside (3), koaburaside (4), tachioside (5), and 4-hydroxy-3,5-bis(3-methyl-2-butenyl)benzaldehyde (7). The structures were established on the basis of spectral analysis. The antioxidant activities of the compounds 1-6 were evaluated by the DPPH free radical scavenging assay. Compound 4 exhibited antioxidant activity with an IC50 value of 9.0 μM. Compound 4 also showed weak inhibitory activity against influenza A neuraminidase Post print version of article may differ from published version. This is an electronic version of an article published in He Y, Zhang L, Zhao M, Tsai SH, Zong YY, Che CT. Phenolic compounds from Eurycorymbus cavaleriei. Journal of Asian Natural Products Research. 2011 Jun;13(6):575-80.. Journal of Asian Natural Products Research is available online at: http://www.informaworld.com/smpp/ DOI:10.1080/10286020.2011.575068 Wed, 01 Jun 2011 05:00:00 GMT http://hdl.handle.net/10027/8732 2011-06-01T05:00:00Z http://hdl.handle.net/10027/8507 The Association Between Physical Functioning and Self-rated General Health in Later Life: The Implications of Social Comparison Yin, Hongjun; Lin, Swu-Jane; Kong, Sheldon X.; Benzeroual, Kenza; Crawford, Stephanie Y.; Hedeker, Donald; Lambert, Bruce L.; Muramatsu, Naoko Self-rated general health has been used widely in health surveys as a single-item measurement of health-rated quality of life. Heterogeneity in self-evaluation of health has been well documented, yet the causes of this heterogeneity are poorly understood. This study evaluated the moderating effects of age, aging, gender, race, education and income on the relationship between physical functioning and self-rated general health using social comparison theory as a guiding framework. A longitudinal mixed-effects regression model was used to analyze a cohort enrolled into the Health and Retirement Study in 1993 that was interviewed at baseline and during four subsequent waves. The results revealed that the association between physical functioning and self-rated general health is weaker among subgroups that tend to have lower health status; i.e., older individuals, non-Caucasians and less educated individuals. These findings suggest the usefulness of social comparison theory in explaining self-rated general health and provide the basis for future research. Post print version of article may differ from published version. The original publication is available at springerlink.com; DOI: 10.1007/s11482-010-9109-3 Tue, 01 Mar 2011 06:00:00 GMT http://hdl.handle.net/10027/8507 2011-03-01T06:00:00Z http://hdl.handle.net/10027/8506 A bacterial PriB with weak single-stranded DNA binding activity can stimulate the DNA unwinding activity of its cognate PriA helicase Feng, Cui; Sunchu, Bharath; Greenwood, Mallory E.; Lopper, Matthew E. Background: Bacterial DNA replication restart pathways facilitate reinitiation of DNA replication following disruptive encounters of a replisome with DNA damage, thereby allowing complete and faithful duplication of the genome. In Neisseria gonorrhoeae, the primosome proteins that catalyze DNA replication restart differ from the well-studied primosome proteins of E. coli with respect to the number of proteins involved and the affinities of their physical interactions: the PriA:PriB interaction is weak in E. coli, but strong in N. gonorrhoeae, and the PriB:DNA interaction is strong in E. coli, but weak in N. gonorrhoeae. In this study, we investigated the functional consequences of this affinity reversal. Results: We report that N. gonorrhoeae PriA’s DNA binding and unwinding activities are similar to those of E. coli PriA, and N. gonorrhoeae PriA’s helicase activity is stimulated by its cognate PriB, as it is in E. coli. This finding is significant because N. gonorrhoeae PriB’s single-stranded DNA binding activity is weak relative to that of E. coli PriB, and in E. coli, PriB’s single-stranded DNA binding activity is important for PriB stimulation of PriA helicase. Furthermore, a N. gonorrhoeae PriB variant defective for binding single-stranded DNA can stimulate PriA’s helicase activity, suggesting that DNA binding by PriB might not be important for PriB stimulation of PriA helicase in N. gonorrhoeae. We also demonstrate that N. gonorrhoeae PriB stimulates ATP hydrolysis catalyzed by its cognate PriA. This activity of PriB has not been observed in E. coli, and could be important for PriB stimulation of PriA helicase in N. gonorrhoeae. Conclusions: The results of this study demonstrate that a bacterial PriB homolog with weak single-stranded DNA binding activity can stimulate the DNA unwinding activity of its cognate PriA helicase. While it remains unclear if N. gonorrhoeae PriB’s weak DNA binding activity is required for PriB stimulation of PriA helicase, the ability of PriB to stimulate PriA-catalyzed ATP hydrolysis could play an important role. Thus, the weak interaction between N. gonorrhoeae PriB and DNA might be compensated for by the strong interaction between PriB and PriA, which could result in allosteric activation of PriA’s ATPase activity. © 2011 Feng et al.; licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. doi:10.1186/1471-2180-11-189 Mon, 01 Aug 2011 05:00:00 GMT http://hdl.handle.net/10027/8506 2011-08-01T05:00:00Z