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131.
In this work, Isatis tinctoria hairy root cultures (ITHRCs) were established as an alternative source for flavonoids (FL) production. I. tinctoria hairy root line V was found to be the most efficient line and was further confirmed by the PCR amplification of rolB, rolC and aux1 genes. Culture parameters of ITHRCs were optimized by Box-Behnken design (BBD), and eight bioactive FL constituents (rutin, neohesperidin, buddleoside, liquiritigenin, quercetin, isorhamnetin, kaempferol and isoliquiritigenin) were quali-quantitatively determined by LC-MS/MS. Under optimal conditions, the total FL accumulation of ITHRCs (24 day-old) achieved was 438.10 μg/g dry weight (DW), which exhibited significant superiority as against that of 2 year-old field grown roots (341.73 μg/g DW). Additionally, in vitro antioxidant assays demonstrated that ITHRCs extracts exhibited better antioxidant activities with lower IC50 values (0.41 and 0.39, mg/mL) as compared to those of field grown roots (0.56 and 0.48, mg/mL). To the best of our knowledge, this is the first report describing FL production and antioxidant activities from ITHRCs. 相似文献
132.
Fen Liu Dilare Adi Xiang Xie Xiao-Mei Li Zhen-Yan Fu Chun-Fang Shan Ying Huang Bang-Dang Chen Min-Tao Gai Xiao-Ming Gao Yi-Tong Ma Yi-Ning Yang 《PloS one》2015,10(12)
Objectives
Little is known about isolated diastolic hypertension (IDH) among different ethnicity groups. We aimed to investigate the prevalence and risk factors for IDH among the major ethnicity population i.e. Han, Uygur and Kazakh in Xinjiang, northwestern part of China.Methods
In total, 14,618 adult participants (7,799 males, 6,819 females) were recruited from the Cardiovascular Risk Survey conducted during 2007 and 2010. Blood pressure, body mass index and standard lipid profile and fasting glucose level from plasma were measured.Results
The overall prevalence of IDH was 10.8% in the Han, 4.5% in the Uygur and 8.7% in the Kazakh populations. When stratified by gender, IDH prevalence was 9.8% in men and 6.8% in women (P<0.001). The prevalence of IDH also varied significantly with age and it was highest in those aged 35–44 yrs old (9.7%) and lowest in those over 75 yrs old (4.1%, P<0.001). Multivariate logistic regression analysis showed that overweight (OR = 1.179, 95%CI: 1.015–1.369) or obesity (OR = 1.202, 95%CI: 1.015–1.424), smoking (OR = 1.362, 95%CI: 1.156–1.604) and high total cholesterol (TC) hyperlipidemia (OR = 1.237, 95%CI: 1.074–1.423) were significantly associated with a higher prevalence of IDH. Identified risk factors for IDH differed among ethnicity groups with male gender, young age (35–44 yrs old), more coffee or tea consumption and high TC hyperlipidemia in the Han; smoking and often coffee or tea consumption in the Uygur and male gender and overweight or obesity in the Kazakh populations.Conclusions
IDH prevalence in the Han population is higher than that in the Uygur and Kazak populations in Xinjiang, northwestern part of China. Male gender, middle age, overweight or obesity, smoking and high TC hyperlipidemia appear to be relevant risk factors of IDH in adults. Different ethnicity background had different sets of risk factors for IDH. 相似文献133.
Jiexin Liu Yongzhi Li Bart Verheyden Shanguang Chen Zhanghuang Chen Yuqing Gai Jianzhong Liu Jianyi Gao Qiong Xie Ming Yuan Qin Li Li Li André E. Aubert 《PloS one》2015,10(3)
Purpose
The objective was to investigate autonomic control in groups of European and Chinese astronauts and to identify similarities and differences.Methods
Beat-to-beat heart rate and finger blood pressure, brachial blood pressure, and respiratory frequency were measured from 10 astronauts (five European taking part in three different space missions and five Chinese astronauts taking part in two different space missions). Data recording was performed in the supine and standing positions at least 10 days before launch, and 1, 3, and 10 days after return. Cross-correlation analysis of heart rate and systolic pressure was used to assess cardiac baroreflex modulation. A fixed breathing protocol was performed to measure respiratory sinus arrhythmia and low-frequency power of systolic blood pressure variability.Results
Although baseline cardiovascular parameters before spaceflight were similar in all astronauts in the supine position, a significant increase in sympathetic activity and a decrease in vagal modulation occurred in the European astronauts when standing; spaceflight resulted in a remarkable vagal decrease in European astronauts only. Similar baseline supine and standing values for heart rate, mean arterial pressure, and respiratory frequency were shown in both groups. Standing autonomic control was based on a balance of higher vagal and sympathetic modulation in European astronauts.Conclusion
Post-spaceflight orthostatic tachycardia was observed in all European astronauts, whereas post-spaceflight orthostatic tachycardia was significantly reduced in Chinese astronauts. The basis for orthostatic intolerance is not apparent; however, many possibilities can be considered and need to be further investigated, such as genetic diversities between races, astronaut selection, training, and nutrition, etc. 相似文献134.
135.
Previous studies have shown that Astragalus polysaccharides (APS) can be used to treat general gastrointestinal disturbances including intestinal mucosal injury. However, the mechanism by which APS mediate this effect is unclear. In the present study, the effects of APS on proliferation, migration, and differentiation of intestinal epithelial cells (IEC-6) were assessed using an in vitro wounding model and colorimetric thiazolyl blue (MTT) assays. The effect of APS on IEC-6 cell differentiation was observed using a light microscope and scanning electron microscope, and the expression of differentiation-specific markers of IEC-6 cells, such as cytokeratin 18 (CK18), alkaline phosphatase (ALP), tight junction protein ZO-2, and sucrase-isomaltase (SI), was determined by immunofluorescence assay (IFA) and real-time PCR. In addition, APS-induced signaling pathways in IEC-6 cells were characterized. Our results indicated that APS significantly enhance migration and proliferation of IEC-6 cells in vitro. APS-treated IEC-6 cells have numerous microvilli on their apical surface and also highly express CK18, ALP, ZO-2, and SI. Moreover, APS-treated IEC-6 cells, in which the activity and expression level of ornithine decarboxylase (ODC) were significantly elevated, also exhibited an increase in cellular putrescine, whereas no significant increase in TGF-β levels was observed. These findings suggest that APS may enhance intestinal epithelial cell proliferation, migration, and differentiation in vitro by stimulating ODC gene expression and activity and putrescine production, independent of TGF-β. Exogenous administration of APS may provide a new approach for modulating intestinal epithelial wound restitution in vivo. 相似文献
136.
137.
Lee MJ Park SH Han JH Hong YK Hwang S Lee S Kim D Han SY Kim ES Cho KS 《Molecules and cells》2011,31(4):337-342
Hempseed is rich in polyunsaturated fatty acids (PUFAs), which have potential as therapeutic compounds for the treatment of
neurodegenerative and cardiovascular disease. However, the effect of hempseed meal (HSM) intake on the animal models of these
diseases has yet to be elucidated. In this study, we assessed the effects of the intake of HSM and PUFAs on oxidative stress,
cytotoxicity and neurological phenotypes, and cholesterol uptake, using Drosophila models. HSM intake was shown to reduce H2O2 toxicity markedly, indicating that HSM exerts a profound antioxidant effect. Meanwhile, intake of HSM, as well as linoleic
or linolenic acids (major PUFA components of HSM) was shown to ameliorate Aβ42-induced eye degeneration, thus suggesting that these compounds exert a protective effect against Aβ42 cytotoxicity. On the
contrary, locomotion and longevity in the Parkinson’s disease model and eye degeneration in the Huntington’s disease model
were unaffected by HSM feeding. Additionally, intake of HSM or linoleic acid was shown to reduce cholesterol uptake significantly.
Moreover, linoleic acid intake has been shown to delay pupariation, and cholesterol feeding rescued the linoleic acid-induced
larval growth delay, thereby indicating that linoleic acid acts antagonistically with cholesterol during larval growth. In
conclusion, our results indicate that HSM and linoleic acid exert inhibitory effects on both Aβ42 cytotoxicity and cholesterol
uptake, and are potential candidates for the treatment of Alzheimer’s disease and cardiovascular disease. 相似文献
138.
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140.
利用微藻固定CO2实现碳减排的研究进展 总被引:2,自引:0,他引:2
CO2减排是目前社会经济发展所面临的重大环境问题之一,如何高效、绿色地进行减排已成为各国科研工作者关注与研究的热点。利用微藻技术进行减排符合碳循环规律,显示出很好的应用前景。本文结合笔者近年在利用微藻技术进行碳减排方面的研究工作,从固定CO2的微藻选育、微藻的培养、微藻减排在光生物反应器方面的开发以及CO2减排与污水深度处理及高价值生物质生产的耦合等4个方面对近些年来国内外在利用微藻技术实现CO2减排方面的研究情况进行了归纳与评述,并对前景进行了展望。 相似文献