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61.
This study investigated the effect of butanol extract of AS (ASBUE) on atherosclerosis in apolipoprotein E-deficient (ApoE−/−) mice. The mice were administered ASBUE (390 or 130 mg/kg/day) or rosuvastatin (RSV) via oral gavage for eight weeks. In ApoE−/− mice, ASBUE suppressed the abnormal body weight gain and improved serum and liver biochemical indicators. ASBUE remarkably reduced the aortic plaque area, improved liver pathological conditions, and lipid metabolism abnormalities, and altered the intestinal microbiota structure in ApoE−/− mice. In the vascular tissue of ASBUE-treated mice, P-IKKβ, P-NFκB, and P-IκBα levels tended to decrease, while IκB-α increased in high fat-diet-fed atherosclerotic mice. These findings demonstrated the anti-atherosclerotic potential of ASBUE, which is mediated by the interaction between the gut microbiota and lipid metabolism and regulated via the Nuclear Factor-kappa B (NF-κB) pathway. This work paves the groundwork for subsequent studies to develop innovative drugs to treat atherosclerosis.  相似文献   
62.
The power conversion efficiencies (PCEs) of all-polymer solar cells (all-PSCs) have already exceeded 17%. However, the limited absorption range of an all-polymer system results in significantly reduced short-circuit current density (Jsc), which eventually influences the PCE improvement. To broaden the light absorption of polymer acceptors, herein, benzotriazole is introduced in the core unit of small molecule acceptors and thus two narrow-bandgap polymer acceptors named PTz-BO and PTz-C11 featuring the same molecular backbone and different side-chain length are synthesized. Compared with PTz-C11, the PTz-BO based-all PSCs deliver a slightly reduced Jsc, a large open-circuit voltage (Voc) and a low voltage loss below 0.50 V. Moreover, ternary all-PSCs are constructed by introducing PTz-C11 as a guest component. Benefiting from the reduced recombination, improved exciton generation and dissociation, and balanced charge transport, a high efficiency of 16.58% is obtained for the ternary all-PSCs, with a high Jsc over 25 mA cm−2 without sacrificing the Voc. Such result represents the highest efficiency reported for benzotriazole-based all-PSCs in the literature thus far. This work demonstrates the great potential of benzotriazole for the synthesis of efficient narrow-bandgap polymer acceptors.  相似文献   
63.
陈鹏  宋佳  郭璞  冀瑞卿 《菌物学报》2023,42(1):297-311
蜜环菌属Armillaria真菌具有较高的食药用价值。由于蜜环菌的生长发育过程较复杂,还未完全实现商业化栽培,野生资源的供应受到季节性和地域性的影响。本研究以采自东北地区蜜环菌属的3个菌株为研究对象,通过培养物的形态特征及分子标记确定菌株JG19016为奥氏蜜环菌A. ostoyae,菌株JG19017为高卢蜜环菌A. gallica,菌株JG19018为中国蜜环菌生物种C。奥氏蜜环菌JG19016最适生长温度为25 ℃,高卢蜜环菌JG19017的最适生长温度为22 ℃,中国蜜环菌生物种C JG19018则在22-25 ℃时菌丝生长速度最快;3个菌株最适pH为5-6。奥氏蜜环菌JG19016对葡萄糖和蔗糖利用率较好,高卢蜜环菌JG19017对葡萄糖利用率较好,中国蜜环菌生物种C JG19018对葡萄糖和淀粉利用率较好;蛋白胨对3个菌株促进作用最强,为最适氮源。培养基中加入VB1,对3个菌株的菌丝生长均有明显的促进作用。奥氏蜜环菌JG19016菌丝生长的最优培养基配方为:葡萄糖20 g,蛋白胨3 g,磷酸二氢钾2 g,硫酸镁1.5 g,VB1 10 mg,琼脂20 g,水1 L。在木屑基质中培养,其配方的最优碳氮比为38:1,最佳木屑粗细比为3:1以上。出菇条件探索结果显示,菌丝及菌索长满菌袋(17 mm×33 mm×5 mm丝聚乙烯袋)需要50-60 d,之后在18 ℃、60%湿度和12 h散射光的环境中,10 d左右可观察到原基产生。增加菇房湿度到90%-95%,2-3 d可观察到1-3 cm的幼子实体,7 d左右菌柄和菌盖完全分化,10 d左右观察到菌盖展开。  相似文献   
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65.
Serine esterases (SEs) are hydrolases that catalyze the conversion of carboxylic esters into acids and alcohols. Lipases and carboxylesterases constitute two major groups of SEs. Although over a hundred of insect genomes are known, systematic identification and classification of SEs are rarely performed, likely due to large size and complex composition of the gene family in each species. Considering their key roles in lipid metabolism and other physiological processes, we have categorized 144 M. sexta SEs and SE homologs (SEHs), 114 of which contain a motif of GXSXG. Multiple sequence alignment and phylogenetic tree analysis have revealed 39 neutral lipases (NLs), 3 neutral lipase homologs (NLHs), 11 acidic lipases (ALs), 3 acidic lipase homologs (ALHs), a lipase-3, a triglyceride lipase, a monoglyceride lipase, a hormone-sensitive lipase, and a GDSL lipase. Eighty-three carboxylesterase genes encode 29 α-esterases (AEs), 12 AEHs (e.g., SEH4-1–3), 20 feruloyl esterases (FEs), 2 FEHs, 2 β-esterases (BEs), 2 integument esterases (IEs), 1 IEH, 4 juvenile hormone esterases, 2 acetylcholinesterases, gliotactin, 6 neuroligins, neurotactin, and an uncharacteristic esterase homolog. In addition to these GXSXG proteins, we have identified 26 phospholipases and 13 thioesterases. Expression profiling of these genes in specific tissues and stages has provided insights into their functions including digestion, detoxification, hormone processing, neurotransmission, reproduction, and developmental regulation. In summary, we have established a framework of information on SEs and related proteins in M. sexta to stimulate their research in the model species and comparative investigations in agricultural pests or disease vectors.  相似文献   
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67.
为快速鉴定糜子(Panicum miliaceum)资源, 建立分子标记检测平台, 以272份山西糜子核心种质为研究材料, 利用85对简单重复序列(SSR)引物, 应用ID Analysis 4.0软件, 构建DNA分子身份证。结果表明, 对85对SSR引物进行筛选, 发现20对引物组合(RYW67、RYW53、RYW37、RYW65、RYW62、RYW77、RYW5、RYW49、RYW84、RYW19、RYW11、RYW40、RYW54、RYW28、RYW31、RYW7、RYW16、RYW8、RYW9和RYW18)可区分272份材料。共检测到等位变异(Na) 60个, 平均每个位点检出3个; Shannon多样性指数(I)为0.957 8 (RYW16)-1.096 7 (RYW5), 平均值为1.055 2; 多态性信息含量(PIC)为0.604 4 (RYW77)-0.753 0 (RYW37), 平均值为0.692 1。利用20对引物构建山西糜子核心种质的字符串、条形码和二维码DNA分子身份证, 可为种质身份标识和溯源提供实践路径。  相似文献   
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69.
Cuticular hydrocarbons of Cerambycidae species can function as signals for sex recognition. Little is known about the copulatory signals of the juniper bark borer Semanotus bifasciatus, a major economic threat to Platycladus orientalis Franco in China. Here, we investigated the cuticular hydrocarbons of both sexes of S. bifasciatus to determine the chemically mediated mating signals using the solid-phase microextraction (SPME) technique with carbowax/divinylbenzene fibers (CAR/DVB) and then analyzed by coupled gas chromatography-mass spectrometry (GC-MS). A series of aliphatic saturated straight-chain n-alkanes (n-C23 to n-C28), internally branched monomethylalkanes at carbons 3, 11, or 13, and dimethylalkanes were identified, which showed no qualitative differences in either sex and were similar in the samples with SPME fiber extraction and those with hexane extraction. The bioassay showed that 11-methylpentacosane (11-MeC25), 11-methylhexacosane (11-MeC26), and 11-methylheptacosane (11-MeC27) have sex-specific recognition functions that triggered more mating attempts at a female-specific ratio of 100:4:60 than at a male-specific ratio of 100:85:50. In addition, the female-specific ratio of 11-methylalkanes can elicit about 70% of male mating attempts within about 60 s, whereas live females elicit about 98% of male mating attempts within 25 s. The discrepancy in the initiation of mating attempts by synthetic mixtures and live females suggests that the methyl isomers 3-MeC25, 3-MeC27, and/or 11,15-diMeC27 may also be involved in the mating behavior of S. bifasciatus. These results suggest that 11-MeC25, 11-MeC26, and 11-MeC27 constitute the contact sex pheromone of S. bifasciatus, with the presence or absence of 11-MeC26 in particular playing an important role in mate recognition by males.  相似文献   
70.
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