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We present a rapid and high-throughput human serum N-glycan preparation technology using 96-well plate-based procedures. The released N-glycans from polyvinylidene fluoride (PVDF) membrane filter plate are subsequently loaded to porous graphitic carbon (PGC) containing a 96-well plate to remove salts and other contaminants without sacrificing accuracy or reproducibility. This robust glycan preparation technology is applied to ovarian cancer diagnosis using 5 μl of patient serum. 相似文献
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In the present study, non‐thermal dielectric barrier discharge (DBD) plasma of induced structural changes of morin resulted in the isolation of one previously undescribed benzofuranone derivative, along with two known compounds. The chemical structures of these degradation products were elucidated by UV, NMR and FAB‐MS spectroscopic analyses. The isolated three compounds showed potent antioxidative activities in two different tests, with IC50 values in the range of 12.9–41.8 μm in the 2,2′‐azino‐bis (3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS+) radical scavenging activity, 19.0–71.9 μm for hydroxyl radical scavenging activity test. Furthermore, the new methoxylated benzofuranone exhibited enhancement of inhibitory effects against pancreatic lipase with an IC50 value of 90.7±1.6 μm , when compared to the parent morin. These results suggested that the degradation products isolated from plasma exposed morin might be beneficial for prevention of obesity and related diseases. 相似文献
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Ting Ji Jia-Jia Wu Qiao-Qiao He Jing-Jing Xu Ruth Mace Yi Tao 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2013,368(1631)
The matrilineal Mosuo of southwestern China live in communal households where brothers and sisters of three generations live together (duolocal residence), and men visit their wives, who reside elsewhere, only at night in ‘visiting’ marriages. Here we show that these communally breeding sisters are in reproductive conflict, in the sense that they share the resources needed to reproduce. We analyse determinants of reproductive success in females and males, and show that co-resident female kin are in competition; the more female kin reside in the household, the more reproductive success is reduced. Male reproductive success, however, is not determined by the kin in his natal household; duolocal males are not in reproductive conflict with their siblings. Competition with female cousins can be worse than that between sisters. We also find that female work on the farm (which is the main communal resource) is not equal. We use a ‘tug-of-war’ model of reproductive skew generated by incomplete control, to model the patterns of effort put into competition between sisters and cousins. The model predicts that more dominant (older) sisters will put less effort into reproductive conflict than will less dominant (younger) sisters; but younger sisters will also have lower reproductive success because they are less efficient at gaining access to the shared resource. Both predictions are consistent with our data. Younger sisters work less in the fields than do older sisters, which may represent a form of conflict or may be because their average relatedness to the household is lower than that of their more fertile older sisters. 相似文献
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Zhenzhen Zhang Changjiu He Yu Gao Lu Zhang Yukun Song Tianqi Zhu Kuanfeng Zhu Dongying Lv Jing Wang Xiuzhi Tian Teng Ma Pengyun Ji Wei Cui Guoshi Liu 《Aging cell》2021,20(2)
The fecundity reduction with aging is referred as the reproductive aging which comes earlier than that of chronological aging. Since humans have postponed their childbearing age, to prolong the reproductive age becomes urgent agenda for reproductive biologists. In the current study, we examined the potential associations of α‐ketoglutarate (α‐KG) and reproductive aging in mammals including mice, swine, and humans. There is a clear tendency of reduced α‐KG level with aging in the follicle fluids of human. To explore the mechanisms, mice were selected as the convenient animal model. It is observed that a long term of α‐KG administration preserves the ovarian function, the quality and quantity of oocytes as well as the telomere maintaining system in mice. α‐KG suppresses ATP synthase and alterations of the energy metabolism trigger the nutritional sensors to down‐regulate mTOR pathway. These events not only benefit the general aging process but also maintain ovarian function and delay the reproductive decline. Considering the safety of the α‐KG as a naturally occurring molecule in energy metabolism, its utility in reproduction of large mammals including humans deserves further investigation. 相似文献
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The present study optimized the extraction characterization and antioxidant activities of water-soluble compound polysaccharides (CPs) from hawthorn, lotus leaf, Fagopyrum tataricum, semen cassiae, Lycium barbarum, and Poria cocos Chinese herbal medicines that have mass ratios of 4 : 2 : 2 : 1.5 : 1 : 1. The CPs yield equation was predicted using quantitative theory, to which a maximum CPs yield of 7.18±0.24 % under the following optimal extraction conditions: a water-to-raw material ratio of 30 mL/g, an extraction temperature of 65 °C, an extraction time of 45 min, and extraction mode ultrasonic-assistant extraction. CPs were consisted of Ara, Gal, Glc, Xyl, Man, GalA and GlcA in a molar ratio of 3.1 : 2.6 : 50.6 : 1.7 : 20.4 : 17.2 : 4.2. The HPGPC profiles and FT-IR spectra implied that CPs were heterogeneous acidic polysaccharides and possessed the β-d -pyranose configuration. Congo red test, CD spectrum and SEM revealed that CPs with three helix conformation showed a flocculent, granulous or sheet-like appearance. Furthermore, the relationships between antioxidant activity and concentration of CPs displayed significant positive correlation, and the scavenging abilities for DPPH, hydroxyl radical, ABTS, superoxide-anion radical and reducing power of CPs were 93.56±2.51 %, 84.03±1.69 %, 83.29±1.93 %, 37.49±1.93 % and 0.467±0.006 at a concentration of 4.0 mg/mL. Therefore, CPs could be applied as a potential natural antioxidant in pharmaceutical or functional food fields. 相似文献
30.
Jianjun Wang Janne Soininen Yong Zhang Beixin Wang Xiangdong Yang Ji Shen 《Journal of Biogeography》2011,38(3):595-603
Aim Data and analyses of elevational gradients in diversity have been central to the development and evaluation of a range of general theories of biodiversity. Elevational diversity patterns have, however, been severely understudied for microbes, which often represent decomposer subsystems. Consequently, generalities in the patterns of elevational diversity across different trophic levels remain poorly understood. Our aim was to examine elevational gradients in the diversity of macroinvertebrates, diatoms and bacteria along a stony stream that covered a large elevational gradient. Location Laojun Mountain, Yunnan province, China. Methods The sampling scheme included 26 sites spaced at elevational intervals of 89 m from 1820 to 4050 m elevation along a stony stream. Macroinvertebrate and diatom richness were determined based on the morphology of the specimens. Taxonomic richness for bacteria was quantified using a molecular fingerprinting method. Over 50 environmental variables were measured at each site to quantify environmental variables that could correlate with the patterns of diversity. We used eigenvector‐based spatial filters with multiple regressions to account for spatial autocorrelation. Results The bacterial richness followed an unexpected monotonic increase with elevation. Diatoms decreased monotonically, and macroinvertebrate richness showed a clear unimodal pattern with elevation. The unimodal richness pattern for macroinvertebrates was best explained by the mid‐domain effect (r2 = 0.72). The diatom richness was best explained by the variation in nutrient supply, and the increase in bacterial richness with elevation may be related to an increased carbon supply. Main conclusions We found contrasting patterns in elevational diversity among the three studied multi‐trophic groups comprising unicellular and multicellular aquatic taxa. We also found that there may be fundamental differences in the mechanisms underlying these species diversity patterns. 相似文献