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51.
Min Sun Shin Jin Soo Lee Naeun Lee Won-Woo Lee Sang Hyun Kim Insoo Kang 《Cytokine》2013,61(2):485-490
We investigated whether healthy young (age ? 40) and elderly (age ? 65) people infected with cytomegalovirus (CMV) had similar levels of CD8+ T cell cytokine production and proliferation in response to an immunodominant CMV pp65 peptide pool given the role of CD8+ T cells in controlling viral infection and the association of CMV with immunosenescence. Plus, we determined the effects of aging and CMV-infectious status on plasma levels of IL-27, an innate immune cytokine with pro- and anti-inflammatory properties, as well as on its relationship to IFN-γ in that IL-27 can promote the production of IFN-γ. The results of our study show that young and elderly people had similar levels of CD8+ T cell proliferation, and IFN-γ and TNF-α production in response to CMV pp65 peptides. Plasma levels of IL-27 were similar between the two groups although CMV-infected young and elderly people had a trend toward increased levels of IL-27. Regardless of aging and CMV-infectious status, plasma levels of IL-27 correlated highly with plasma levels of IFN-γ. These findings suggest the maintenance of CMV pp65-specific CD8+ T cell proliferation and cytokine production with aging as well as the sustaining of circulatory IL-27 levels and its biological link to IFN-γ in young and elderly people irrespective of CMV infection. 相似文献
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Although more than 60 ancient hominid track sites ranging in age from 3.7 million to less than 500 B. P. are recorded from all continents except Antarctica, no ichnotaxonomic names have ever been formally proposed for hominid tracks. There is no prohibition to the naming of fossil footprints of species that created tracks and trackways similar to those of living species. On the contrary, there is precedent for the naming of ichnotaxa corresponding to the dominant extant vertebrates classes: mammals = Mammalipedia and birds = Avipeda. The hominid track site sample includes only about a dozen sites where footprint preservation is good enough to show details of diagnostic foot morphology and typical trackway morphology. We infer that the Acahualinca Footprint Museum site in Nicaragua represents the most important ancient hominid track site that combines accessibility, a large sample of well-preserved trackways and reliable dating. For this reason, we select the Nicaraguan tracks as the type sample for the new ichnotaxon Hominipes modernus ichnogen., and ichnsp. et ichnosp. nov., which we infer to represent fully modern Homo sapiens. Our preliminary investigations of other track sites suggest that the majority also yield H. modernus. However, at many sites preservation is insufficient to make an ichnotaxonomic designation at the species level or to infer that the trackmaker was H. sapiens. Thus, at many sites including the famous Laetoli site, we apply the more general label of Hominipes isp. indet. 相似文献
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In Disney/Pixar's phenomenally popular animated film Finding Nemo (Stanton, 2003), one of the central themes of fish welfare was highlighted when the moorish idol, Gill, commented, “Fish aren't meant to be kept in a box, kid. It does things to you.” The notion that fish might have the capacity to suffer in captivity (Chandroo, Duncan, & Moccia, 2004a, 2004b) links to the larger question of sentiency, which remains a fundamental tenet when justifying concerns for nonhuman animal welfare (Dawkins, 2006; Huntingford et al., 2006). Although terrestrial nonhuman-animal welfare has been discussed and explored for many years, the development of aquatic animal welfare concepts and approaches remains relatively new and beyond public awareness (Braastad, Damsgård, & Juell, 2006; Broom, 2007; Farmed Animal Welfare Council, 1996; Fisheries Society of the British Isles, 2002; Håstein, Scarfe, & Lund, 2005; Iwama, 2007; Schreck, 1981). 相似文献
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The aim of the present study was to characterize the enzymatic deinking of various types of waste paper. Studies on the optimization of enzymatic deinking have been performed previously using commercially available enzyme preparations containing cellulase and hemicellulase. The enzymatic deinking of different types of waste paper demonstrated a high efficiency of 86.6% on laser-printed paper, but a low deinking efficiency of 12.9% was obtained with newspaper. All enzymatic treatments significantly improved the drainage rate of the deinked waste paper. Enzymatic deinking increased the tensile index of magazine paper but reduced the tensile index of bubble jet-printed paper, photocopy paper and newspaper. Enzymatic hydrolysis caused a 21.1% reduction in the tear index for bubble jet-printed paper, but a 3.1% increase in the tear index was obtained for laser-printed paper relative to respective blank. In addition, enzymatic hydrolysis increased the burst index by 4.7% relative to blank for laser-printed paper. However, photocopy paper showed the highest reduction (8.3%) in the burst index relative to blank. Taken together, these results suggest that enzymatic hydrolysis is both advantageous and detrimental to the mechanical properties of deinked paper. Thus, the proper regulation of enzymatic hydrolysis is crucial to improve the quality of recycled paper. 相似文献
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Koeun Han Hee-Jin Jeong Joohee Sung Young Soo Keum Myeong-Cheoul Cho Jeong-Han Kim Jin-Kyung Kwon Byung-Dong Kim Byoung-Cheorl Kang 《Molecular breeding : new strategies in plant improvement》2013,31(3):537-548
Pungency in pepper (Capsicum annuum L.) has unique characteristics due to the alkaloid compound group, capsaicinoids, which includes capsaicin. Although capsaicinoids have been proved to have pharmacological and physiological effects on human health, the application of capsaicinoids has been limited because of their pungency. Capsinoids found in non-pungent peppers share closely related structures with capsaicinoids and show similar biological effects. Previous studies demonstrated that mutations in the p-AMT gene were related to the production of capsinoids; however, the pathway of capsinoid synthesis has not yet been fully elucidated. In this study, we performed genetic analysis to determine the mechanism of capsinoid synthesis using a F6 recombinant inbred line population. In this population, the presence/absence of capsinoids co-segregated with the genotype of the Pun1 locus, without exception. In addition, we screened the patterns of capsinoid synthesis and the correlation between the Pun1 locus and capsinoid synthesis in p-AMT mutant accessions. In Capsicum germplasms, we selected amino-acid-substituted mutants in the PLP binding domain of the p-AMT gene. Capsinoids were not synthesized with the recessive pun1 gene, regardless of the p-AMT genotype, and no relationship was found between p-AMT mutant type and capsinoid content. We concluded that the Pun1 gene, which is responsible for capsaicinoid synthesis, also controls capsinoid synthesis. 相似文献
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Ji Hyun Kim In Su Park Yongdoo Park Youngmee Jung Soo Hyun Kim Sang-Heon Kim 《Cytotherapy》2013,15(5):542-556
Background aimsTo successfully treat myocardial infarction (MI), blood must be resupplied to the ischemic myocardium by inducing angiogenesis. Many studies report enhanced angiogenesis using stem cells; however, the therapeutic efficacy of cell transplant remains low because transplanted cells may not survive, be retained at the site of transplant, or develop into vascular tissue. In this study, we assessed the therapeutic potential of three-dimensional cell masses (3DCM) composed of human adipose-derived stem cells (hASC) in a rat MI model.MethodsFor formation of 3DCM, hASC were cultured on a substrate with immobilized fibroblast growth factor 2. The morphology and phenotypes of 3DCM were analyzed 1 day after culture. The cells (hASC and 3DCM, 5 × 105 cells) were injected into ischemic regions after ligation of the left coronary artery (n = 6 in each group). Cell retention ratio, therapeutic efficacy and vascularization were evaluated 4 weeks after transplant.ResultsA spheroid-type 3DCM, which included vascular cells (CD34+/CD31+/KDR+/α-SMA+) with high production of human vascular endothelial growth factor, was obtained. Infarct size and cardiomyocyte apoptosis were reduced in the 3DCM-injected group compared with the hASC-injected group. The retention ratio of hASC was 14-fold higher in the 3DCM-injected group. Many transplanted cells differentiated into endothelial and smooth muscle cells and formed vascular networks incorporated into host vessels.ConclusionsTransplant of 3DCM may be useful for angiogenic cell therapy to treat MI. 相似文献