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61.
Qiangjian Ju Ruguang Ma Yu Pei Beibei Guo Zichuang Li Qian Liu Tiju Thomas Minghui Yang Graham J. Hutchings Jiacheng Wang 《Liver Transplantation》2020,10(21)
The development of Pt‐free catalysts for the alkaline hydrogen evolution reaction (HER), which is widely used in industrial scale water‐alkali electrolyzers, remains a contemporary and pressing challenge. Ruthenium (Ru) has excellent water‐dissociation abilities and could be an alternative water splitting catalyst. However, its large hydrogen binding energy limits HER activity. Here, a new approach is proposed to boost the HER activity of Ru through uniform loading of Ru nanoparticles on triazine‐ring (C3N3)‐doped carbon (triNC). The composite (Ru/triNC) exhibits outstanding HER activity with an ultralow overpotential of ≈2 mV at 10 mA cm?2; thereby making it the best performing electrocatalyst hitherto reported for alkaline HER. The calculated metal mass activity of Ru/triNC is >10 and 15 times higher than that of Pt/C and Pt/triNC. Both theoretical and experimental studies reveal that the triazine‐ring is a good match for Ru to weaken the hydrogen binding on Ru through interfacial charge transfer via increased contact electrification. Therefore, Ru/triNC can provide the optimal hydrogen adsorption free energy (approaching zero), while maintaining the strong water‐dissociation activity. This study provides a new avenue for designing highly efficient and stable electrocatalysts for water splitting. 相似文献
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目的:探讨莫西沙星联合用药方案对耐多药肺结核(MDR-TB)患者血清游离氨基酸和免疫功能的影响。方法:选取2015年9月到2018年1月期间我院收治的90例MDR-TB患者,根据乱数表法将患者分为研究组(n=45)、对照组(n=45),其中对照组给予左氧氟沙星联合常规化疗治疗,研究组则给予莫西沙星联合常规化疗治疗,比较两组临床疗效、痰菌转阴率、病灶吸收率、空洞闭合率、血清游离氨基酸和免疫功能,记录两组治疗期间不良反应情况。结果:研究组治疗18个月后的临床总有效率为71.11%(32/45),高于对照组的46.67%(21/45)(P0.05)。研究组治疗18个月后痰菌转阴率、病灶吸收率、空洞闭合率均较对照组高(P0.05)。两组患者治疗18个月后CD4+、免疫球蛋白A(Ig A)、免疫球蛋白G(Ig G)均升高,CD8+降低(P0.05),研究组治疗18个月后CD4+、Ig A、Ig G高于对照组,而CD8+低于对照组(P0.05)。两组治疗18个月后缬氨酸、谷氨酸均升高,且研究组高于对照组(P0.05)。两组患者总不良反应发生率比较无明显差异(P0.05)。结论:莫西沙星联合常规化疗治疗MDR-TB的疗效确切,可有效改善患者血清游离氨基酸水平,提高机体免疫功能,同时不增加不良反应发生率。 相似文献
64.
Jiayan Li Daiwen Chen Bing Yu Jun He Zhiqing Huang Xiangbing Mao Ping Zheng Jie Yu Junqiu Luo Gang Tian Yuheng Luo 《Microbial biotechnology》2020,13(2):509-521
Despite their important roles in host nutrition and metabolism, and potential to cause disease, our knowledge of the fungal community in the mammalian gut is quite limited. To date, diversity and composition of fungi in swine gut still remains unknown. Therefore, the first internal transcribed spacer of fungi in faecal samples from three breeds of pigs (10 pigs for each breed) was sequenced based on an Illumina HiSeq 2500 platform, and the relationship between the fungal community and the concentrations of main short-chain fatty acids (SCFAs) was also analysed. Results indicated that Chenghua (local, higher body fat rate), Yorkshire (foreign, higher lean meat and growth rate) and Tibetan (plateau, stronger disease resistance) pigs harboured distinct fungal community. The Basidiomycota and Ascomycota presented as the two predominant phyla, with Loreleia, Russula and Candida as the top three genera in all samples. Network analysis revealed a total of 35 correlations among different fungal genera, with 27 (77.14%) positive and 8 (22.86%) negative pairwise interactions. Canonical correspondence analysis suggested that fungi in the faeces of pigs were more correlated to the concentration of acetate and butyrate rather than propionate. Spearman’s correlation further showed that Tomentella was positively correlated to both acetate and butyrate, and Loreleia was positively correlated to propionate (P < 0.05), while Nephroma and Taiwanofungus were negatively correlated to acetate and propionate (P < 0.05). These findings expanded our knowledge on the intestinal fungi in pigs with different genotypes and phenotypes, indicating that fungi may play an indispensable role during the metabolism of host and the maintenance of intestinal health. The cross-feeding between fungi and other microorganisms may be crucial during the digestion of dietary carbohydrates and the associated physiological processes, which is worthy to be further studied. 相似文献
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Genome assembly provides insights into the genome evolution and flowering regulation of orchardgrass
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Gang Fan Mario Kaßmann Yingqiu Cui Claudia Matthaeus Sverine Kunz Cheng Zhong Shuai Zhu Yu Xie Dmitry Tsvetkov Oliver Daumke Yu Huang Maik Gollasch 《Aging cell》2020,19(4)
Caveolae position CaV3.2 (T‐type Ca2+ channel encoded by the α‐3.2 subunit) sufficiently close to RyR (ryanodine receptors) for extracellular Ca2+ influx to trigger Ca2+ sparks and large‐conductance Ca2+‐activated K+ channel feedback in vascular smooth muscle. We hypothesize that this mechanism of Ca2+ spark generation is affected by age. Using smooth muscle cells (VSMCs) from mouse mesenteric arteries, we found that both Cav3.2 channel inhibition by Ni2+ (50 µM) and caveolae disruption by methyl‐ß‐cyclodextrin or genetic abolition of Eps15 homology domain‐containing protein (EHD2) inhibited Ca2+ sparks in cells from young (4 months) but not old (12 months) mice. In accordance, expression of Cav3.2 channel was higher in mesenteric arteries from young than old mice. Similar effects were observed for caveolae density. Using SMAKO Cav1.2?/? mice, caffeine (RyR activator) and thapsigargin (Ca2+ transport ATPase inhibitor), we found that sufficient SR Ca2+ load is a prerequisite for the CaV3.2‐RyR axis to generate Ca2+ sparks. We identified a fraction of Ca2+ sparks in aged VSMCs, which is sensitive to the TRP channel blocker Gd3+ (100 µM), but insensitive to CaV1.2 and CaV3.2 channel blockade. Our data demonstrate that the VSMC CaV3.2‐RyR axis is down‐regulated by aging. This defective CaV3.2‐RyR coupling is counterbalanced by a Gd3+ sensitive Ca2+ pathway providing compensatory Ca2+ influx for triggering Ca2+ sparks in aged VSMCs. 相似文献
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