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71.
Lianpeng Chang Zhenghong Sui Feng Fu Wei Zhou Jinguo Wang Kyoung Ho Kang Shu Zhang Jinhua Ma 《Journal of applied phycology》2014,26(6):2435-2441
UDP-glucose pyrophosphorylase (UGPase) is an enzyme involved in the biosynthesis of UDP-D-galactose, a subunit of agar in red seaweeds. The relationship between agar content and expression levels of the UGPase encoding gene (glugp) was studied in thalli under different treatment conditions using a quantitative real-time PCR-based method (qPCR). Moreover, this qPCR method for the measurement of glugp expression was also applied to commercial varieties of Gracilariopsis lemaneiformis, a red macroalga, in order to examine its reliability on material obtained from field cultivation. Both the agar content and glugp gene expression in G. lemaneiformis grown under low salinity (17?‰) conditions for 1 week showed a slight increase in comparison with the control group (33?‰ salinity, natural salinity of seawater), but the difference was not statistically significant (P?>?0.05). However, when the culture time was extended to 2 weeks, the increase in both the agar yield and glugp expression became significant (P?0.01). However, phosphate limitation for 2 weeks had little effect on agar content and glugp expression (P?>?0.05). Our results suggest that glugp gene expression and agar content are highly positively correlated and that the measurement of glugp expression, using only a small amount of thalli material, may be an efficient approach to evaluate agar content. In addition, both the agar content and glugp expression in cultivars 981, 07-2, and ZC differed significantly from those of MT-18. The findings of this study suggest that UGPase may be involved in agar biosynthesis and indicate that glugp gene expression could be a fairly reliable molecular marker to reflect the agar content of strains during breeding and selection of G. lemaneiformis. 相似文献
72.
Razak Muhammad Raznisyafiq Aris Ahmad Zaharin Yusoff Fatimah Md Yusof Zetty Norhana Balia Kim Sang Don Kim Kyoung Woong 《Marine biotechnology (New York, N.Y.)》2023,25(3):473-487
Marine Biotechnology - Moina micrura represents a promising model species for ecological and ecotoxicological investigations in tropical freshwater ecosystems. Illumina NovaSeq™ 6000... 相似文献
73.
Kyungdo Han Yu-Mi Park Hyuk-Sang Kwon Seung-Hyun Ko Seung-Hwan Lee Hyeon Woo Yim Won-Chul Lee Yong Gyu Park Mee Kyoung Kim Yong-Moon Park 《PloS one》2014,9(1)
Background
Blood pressure (BP) is directly and causally associated with body size in the general population. Whether muscle mass is an important factor that determines BP remains unclear.Objective
To investigate whether sarcopenia is associated with hypertension in older Koreans.Participants
We surveyed 2,099 males and 2,747 females aged 60 years or older.Measurements
Sarcopenia was defined as an appendicular skeletal muscle mass divided by body weight (ASM/Wt) that was <1 SD below the gender-specific mean for young adults. Obesity was defined as a body mass index (BMI) ≥25 kg/m2. Subjects were divided into four groups based on presence or absence of obesity or sarcopenia. Hypertension was defined as a systolic BP (SBP) ≥140 mmHg, a diastolic BP (DBP) ≥90 mmHg, or a self-reported current use of antihypertensive medications.Results
The overall prevalence of hypertension in the four groups was as follows 49.7% for non-obese non-sarcopenia, 60.9% for non-obese sarcopenia, 66.2% for obese non-sarcopenia and 74.7% for obese sarcopenia. After adjustment for age, gender, regular activity, current smoking and alcohol use, the odds ratio (OR) for having hypertension was 1.5 (95% confidence interval (CI) = 1.23–1.84) in subjects in the non-obese sarcopenia group, 2.08 (95% CI = 1.68–2.57) in the obese non-sarcopenia group and 3.0 (95% CI = 2.48–3.63) in the obese sarcopenia group, compared with the non-obese non-sarcopenia group (p for trend <0.001). Controlling further for body weight and waist circumference did not change the association between hypertension and sarcopenia. The association between sarcopenia and hypertension was more robust in the subjects with diabetes mellitus.Conclusion
Body composition beyond BMI has a considerable impact on hypertension in elderly Koreans. Subjects with sarcopenic obesity appear to have a greater risk of hypertension than simply obese or sarcopenia subjects. 相似文献74.
Sun-Young Lee Ji-Hyun Ahn Kyoung Won Ko Jaetaek Kim Seong Whan Jeong In-Kyung Kim Jin Kim Ho-Shik Kim 《Prostaglandins & other lipid mediators》2010,91(1-2):30-37
HL-60 cells treated by prostaglandin (PG) A2 showed characteristics of apoptosis such as accumulation of hypodiploid and annexin V positive cells, condensed and fragmented nuclei, cytochrome c (Cyt C) release from mitochondria and activation of caspase-1, -2, -3, -7 and -9. PGA2-induced cell death was rescued by inhibitors of caspase-9 and -3, but PGA2-induced Cyt C release was not prevented by caspase inhibitors. During Cyt C release by PGA2, mitochondrial transmembrane potential was maintained and mitochondrial permeability transition pore was not formed. In addition, anti-apoptotic BCL-2 family proteins like BCL-2 and BCL-XL, and ROS scavengers including ascorbic acid and 2,2,6,6-tetramethyl-1-piperidinyloxy were not able to inhibit Cyt C release as well as apoptosis by PGA2. Finally, it was shown that PGA2-induced Cyt C release in vitro from purified mitochondria in the absence of cytosolic components. Furthermore, thiol-containing compounds such as N-acetylcysteine, l-cysteine and monothioglycerol prevented Cyt C release, and hence induction of apoptosis. Taken together, these results suggest that PGA2 activates intrinsic apoptotic pathway by directly stimulating mitochondrial outer membrane permeabilization to release Cyt C, in which thiol-reactivity of PGA2 plays a pivotal role. 相似文献
75.
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77.
Low-dose radiation stimulates the proliferation of normal human lung fibroblasts via a transient activation of Raf and Akt 总被引:1,自引:0,他引:1
Kim CS Kim JK Nam SY Yang KH Jeong M Kim HS Kim CS Jin YW Kim J 《Molecules and cells》2007,24(3):424-430
The biological effects of low-dose radiation have been investigated and debated for more than a century, but its cellular effects and regulatory mechanisms remain poorly understood. This study shows the human cellular responses to low-dose radiation in CCD-18 Lu cells, which are derived from normal human lung fibroblasts. We examined a colony-forming assay for cell survival by ionizing radiation. Live cell counting and cell cycle analysis were measured for cell proliferation and cell cycle progression following low-dose irradiation. We examined Raf and Akt phosphorylation to determine the proliferation mechanism resulting from low-dose radiation. We also observed that p53 and p21 were related to cell cycle response. We found that 0.05 Gy of ionizing radiation enhanced cell proliferation and did not change the progression of the cell cycle. In addition, 0.05 Gy of ionizing radiation transiently activated Raf and Akt, but did not change phospho-p53, p53 and p21 in CCD-18 Lu cells. However, 2 Gy of ionizing radiation induced cell cycle arrest, phosphorylation of p53, and expression of p53 and p21. The phosphorylation of Raf and Akt proteins induced by 0.05 Gy of ionizing radiation was abolished by pre-treatment with an EGFR inhibitor, AG1478, or a PI3k inhibitor, LY294002. Cell proliferation stimulated by 0.05 Gy of ionizing radiation was blocked by the suppression of Raf and Akt phosphorylation with these inhibitors. These results suggest that 0.05 Gy of ionizing radiation stimulates cell proliferation through the transient activation of Raf and Akt in CCD-18 Lu cells. 相似文献
78.
A Tn5 transposon mutant was isolated of the alkylphenol degrader Pseudomonas sp. KL28 that showed increased growth at higher levels of m-cresol on solid and in liquid cultures. The transposon was inserted at the 5'-terminus of rpoS, which encodes a stationary-phase sigma factor. When grown on agar plates, the rpoS mutant developed prominent wrinkles, especially at lower temperatures, and spread faster on soft agar. In addition, the rpoS mutant had enhanced biofilm-forming ability that was not due to self-produced diffusible signals. 相似文献
79.