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121.
Hye Suck An Jae Kwon Cho Kyong Min Kim Maeng Hyun Son Jeong In Myeong Chul Min An 《Genes & genomics.》2014,36(5):661-669
The seven-band grouper (Epinephelus septemfasciatus) is an important fishery resource of a target for prospective aquaculture diversification and maintenance of stock quality is thus important. To explore the sustainability of fry production, genetic variations in 83 seven-band groupers from two broodstock and offspring populations of a hatchery strain were analyzed using 13 polymorphic nuclear microsatellite DNA loci; 133 alleles were identified. Allelic variability ranged from 4 to 18 in the broodstock and from 3 to 11 in the offspring. The average observed and expected heterozygosities were 0.669 and 0.734 in broodstock and 0.674 and 0.649 in offspring, respectively. Although no statistically significant reductions in heterozygosity or allelic diversity were evident in offspring, considerable loss of rare alleles was apparent. The broodstock and offspring populations exhibited significant genetic differences (F ST = 0.033, P < 0.001) indicating that genetic drift has likely promoted differentiation between the two populations, which may have negative effects on sustainable fry production. Therefore, genetic variations between broodstock and offspring should be monitored, and inbreeding should be controlled, to ensure the success of commercial breeding programs. Our data provide a useful genetic basis for future planning of sustainable culture and management of E. septemfasciatus in fisheries. 相似文献
122.
Background
EKC is transmitted chiefly by direct hand contact. It is suspected that the 2009/2010 influenza pandemic influenced hand washing. This study aims to examine the relationship between the 2009/2010 H1N1 influenza pandemic and hygiene behavior.Methods
We compared the EKC prevalence trends before, during and after the 2009/2010 influenza pandemic by using a t-test comparison of EKC sentinel surveillance.Results
During the pre-pandemic period, the incidence of EKC increased from the 21st to the 44th week each year. However, during the pandemic period in 2009, there was no epidemic peak. In the post-pandemic period, the epidemic curve was similar to that in the pre-pandemic period. Compared to the pre-pandemic period, the total number of EKC patients during the pandemic period showed a decrease of 44.9% (t value = −7.23, p = 0.002). Comparing the pre-pandemic and pandemic periods by age group, we found there to be a significant decrease in the number of EKC patients for all age groups (−4.12≤t value≤−7.23, all P<0.05). This finding was most evident in the teenage group (62%) compared to the other age groups (decreases of 29 to 44%).Conclusions
A continuing effort should be made to educate the public on basic infection prevention behaviors in the aftermath of the pandemic, particularly to teenagers. 相似文献123.
Genetic and Biochemical Characterization of Nectria haematococca Strains with Adhesive and Adhesion-Reduced Macroconidia 下载免费PDF全文
L. Epstein Y. H. Kwon D. E. Almond L. M. Schached M. J. Jones 《Applied microbiology》1994,60(2):524-530
A previous study reported the isolation of two mutants (LE1 and LE2) of the plant pathogenic fungus Nectria haematococca (anamorph, Fusarium solani f. sp. cucurbitae) with macroconidia with reduced ability to adhere (Att-) to zucchini fruits and polystyrene. The adhesion-reduced-phenotype in LE1 and LE2 macroconidia is temperature sensitive and dependent on the concentration of nutrients. Classical genetic analysis of progeny derived from LE1 identified a mutation in a genetic locus, named Att1. The 90-kDa glycoprotein and macroconidial tip mucilage which were previously associated with the development of adhesion competence in Att+ macroconidia are specifically associated with macroconidia; neither is produced on microconidia, which are relatively nonadherent. However, macroconidia of both Att+ and Att- strains produce the 90-kDa glycoprotein and the macroconidial tip mucilage. 相似文献
124.
Human hair growth enhancement in vitro by green tea epigallocatechin-3-gallate (EGCG) 总被引:1,自引:0,他引:1
O.S. Kwon J.H. Han H.G. Yoo J.H. Chung K.H. Cho H.C. Eun K.H. Kim 《Phytomedicine》2007,14(7-8):551-555
Green tea is a popular worldwide beverage, and its potential beneficial effects such as anti-cancer and anti-oxidant properties are believed to be mediated by epigallocatechin-3-gallate (EGCG), a major constituent of polyphenols. Recently, it was reported that EGCG might be useful in the prevention or treatment of androgenetic alopecia by selectively inhibiting 5alpha-reductase activity. However, no report has been issued to date on the effect of EGCG on human hair growth. This study was undertaken to measure the effect of EGCG on hair growth in vitro and to investigate its effect on human dermal papilla cells (DPCs) in vivo and in vitro. EGCG promoted hair growth in hair follicles ex vivo culture and the proliferation of cultured DPCs. The growth stimulation of DPCs by EGCG in vitro may be mediated through the upregulations of phosphorylated Erk and Akt and by an increase in the ratio of Bcl-2/Bax ratio. Similar results were also obtained in in vivo dermal papillae of human scalps. Thus, we suggest that EGCG stimulates human hair growth through these dual proliferative and anti-apoptotic effects on DPCs. 相似文献
125.
In this study, we investigated the effect of the methanol extract of fruits of Vitis amurensis Rupr. (Vitaceae; MEVA) on the mast cell-mediated allergy model and studied the possible mechanism of action. Mast cell-mediated allergic disease is involved in many diseases, such as asthma and sinusitis. The discovery of drugs for the treatment of allergic disease is an important subject in human health. MEVA inhibited compound 48/80-induced systemic reactions and serum histamine release in a dose-dependent manner in mice. MEVA decreased immunoglobulin E (IgE)-mediated local allergic reactions, passive cutaneous anaphylaxis. MEVA dose-dependently reduced histamine release from mast cells activated by compound 48/80 or IgE. The inhibitory effect of MEVA on histamine release was mediated by the modulation of intracellular calcium. In addition, MEVA attenuated the phorbol 12-myristate 13-acetate and calcium ionophore A23187 (PMACI)-stimulated secretion of tumor necrosis factor-alpha, interleukin-6 (IL-6), and IL-8 in human mast cells. The inhibitory effect of MEVA on these proinflammatory cytokines was p38 mitogen-activated protein kinase and nuclear factor-kappaB (NF-kappaB) dependent. Our findings provide evidence that MEVA inhibits mast cell-derived, immediate-type allergic reactions and involvement of proinflammatory cytokines, p38 MAPK, and NF-kappaB in these effects. 相似文献
126.
127.
Jeongjoo Lee You‐Hyun Seo Sung‐Nam Kwon Do‐Hyung Kim Seokhoon Jang Hyeonwoo Jung Youngu Lee Hasitha Weerasinghe Taehyo Kim Jin Young Kim Doojin Vak Seok‐In Na 《Liver Transplantation》2019,9(36)
The record efficiency of the state‐of‐the‐art polymer solar cells (PSCs) is rapidly increasing, due to the discovery of high‐performance photoactive donor and acceptor materials. However, strong questions remain as to whether such high‐efficiency PSCs can be produced by scalable processes. This paper reports a high power conversion efficiency (PCE) of 13.5% achieved with single‐junction ternary PSCs based on PTB7‐Th, PC71BM, and COi8DFIC fabricated by slot‐die coating, which shows the highest PCE ever reported in PSCs fabricated by a scalable process. To understand the origin of the high performance of the slot‐die coated device, slot‐die coated photoactive films and devices are systematically investigated. These results indicate that the good performance of the slot‐die PSCs can be due to a favorable molecule‐structure and film‐morphology change by introducing 1,8‐diiodooctane and heat treatment, which can lead to improved charge transport with reduced carrier recombination. The optimized condition is then used for the fabrication of large‐area modules and also for roll‐to‐roll fabrication. The slot‐die coated module with 30 cm2 active‐area and roll‐to‐roll produced flexible PSC has shown 8.6% and 9.6%, respectively. These efficiencies are the highest in each category and demonstrate the strong potential of the slot‐die coated ternary system for commercial applications. 相似文献
128.
Although nitric oxide (NO) plays key signaling roles in the nervous systems, excess NO leads to cell death. In this study, the involvement of p38 mitogen-activated protein kinase (p38 MAPK) and apoptosis signal-regulating kinase-1 (ASK1) in NO-induced cell death was investigated in PC12 cells. NO donor transiently activated p38 MAPK in the wild type parental PC12 cells, whereas the p38 MAPK activation was abolished in NO-resistant PC12 cells (PC12-NO-R). p38 MAPK inhibitors protected the cells against NO-induced death, whereas the inhibitors were not significantly protective against the cytotoxicity of reactive oxygen species. Stable transfection with dominant negative p38 MAPK mutant reduced NO-induced cell death. Stable transfection with dominant negative mutant of ASK1 attenuated NO-stimulated activation of p38 MAPK and decreased NO-induced cell death. These results suggest that p38 MAPK and its upstream regulator ASK1 are involved in NO-induced PC12 cell death. 相似文献
129.
130.
James M. Daley William A. Gaines YoungHo Kwon Patrick Sung 《Cold Spring Harbor perspectives in biology》2014,6(11)
Homologous recombination (HR) is a major mechanism for eliminating DNA double-strand breaks from chromosomes. In this process, the break termini are resected nucleolytically to form 3′ ssDNA (single-strand DNA) overhangs. A recombinase (i.e., a protein that catalyzes homologous DNA pairing and strand exchange) assembles onto the ssDNA and promotes pairing with a homologous duplex. DNA synthesis then initiates from the 3′ end of the invading strand, and the extended DNA joint is resolved via one of several pathways to restore the integrity of the injured chromosome. It is crucial that HR be carefully orchestrated because spurious events can create cytotoxic intermediates or cause genomic rearrangements and loss of gene heterozygosity, which can lead to cell death or contribute to the development of cancer. In this review, we will discuss how DNA motor proteins regulate HR via a dynamic balance of the recombination-promoting and -attenuating activities that they possess. 相似文献