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Hereditary thrombotic thrombocytopenic purpura (TTP) is an autosomal recessive thrombosis disorder, caused by loss-of-function mutations in ADAMTS13. Mutations in the CUB domains of ADAMTS13 are rare, and the exact mechanisms through which these mutations result in the development of TTP have not yet been fully elucidated. In this study, we identified two novel mutations in the CUB domains in a TTP family with an acceptor splice-site mutation (c.3569−1, G>A, intron 25) and a point missense mutation (c.3923, G>A, exon 28), resulting in a glycine to aspartic acid substitution (p.G1308D). In vitro splicing analysis revealed that the intronic mutation resulted in abnormal pre-mRNA splicing, and an in vitro expression assay revealed that the missense mutation significantly impaired ADAMTS13 secretion. Although both the patient and her brother displayed significantly reduced ADAMTS13 activity and increased levels of ultra-large VWF (ULVWF) multimers in plasma, only the female developed acute episodes of TTP. Our findings indicate the importance of the CUB domains for the protein stability and extracellular secretion of ADAMTS13.  相似文献   
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Poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) has been is applied as hole transport material in organic electronic devices for more than 20 years. However, the redundant sulfonic acid group of PEDOT:PSS has often been overlooked. Herein, PEDOT:PSS‐DA is prepared via a facile doping of PEDOT:PSS with dopamine hydrochloride (DA·HCl) which reacts with the redundant sulfonic acid of PSS. The PEDOT:PSS‐DA film exhibits enhanced work function and conductivity compared to those of PEDOT:PSS. PEDOT:PSS‐DA‐based devices show a power conversion efficiency of 16.55% which is the highest in organic solar cells (OSCs) with (poly[(2,6‐(4,8‐bis(5‐(2‐ethylhexyl)‐4‐fluorothiophen‐2‐yl)benzo[1,2‐b:4,5‐b′]dithio‐phene))‐co‐(1,3‐di(5‐thiophene‐2‐yl)‐5,7‐bis(2‐ethylhexyl)‐benzo[1,2‐c:4,5‐c′]dithiophene‐4,8‐dione))] (PM6):(2,2′‐((2Z,2′Z)‐((12,13‐bis(2‐ethylhexyl)‐3,9‐diundecyl‐12,13‐dihydro‐[1,2,5]thiadiazolo[3,4‐e]thieno[2′′,3′:4′,5′]thieno[2′,3′:4,5]pyrrolo[3,2‐g]thieno[2′,3′:4,5]thieno[3,2‐b]indole‐2,10‐diyl)bis(methanylylidene))bis(5,6‐difluoro‐3‐oxo‐2,3‐dihydro‐1H‐indene‐2,1‐diylidene))dimalononitrile) (Y6) as the active layer. Furthermore, PEDOT:PSS‐DA also exhibits enhanced performance in three other donor/acceptor systems, exhibiting high compatibility in OSCs. This work demonstrates that doping PEDOT:PSS with various amino derivatives is a potentially efficient strategy to enhance the performance of PEDOT:PSS in organic electronic devices.  相似文献   
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Grain size and plant architecture are critical factors determining crop productivity. Here, we performed gene editing of the MIR396 gene family in rice and found that MIR396e and MIR396f are two important regulators of grain size and plant architecture. mir396ef mutations can increase grain yield by increasing grain size. In addition, mir396ef mutations resulted in an altered plant architecture, with lengthened leaves but shortened internodes, especially the uppermost internode. Our research suggests that mir396ef mutations promote leaf elongation by increasing the level of a gibberellin (GA) precursor, mevalonic acid, which subsequently promotes GA biosynthesis. However, internode elongation in mir396ef mutants appears to be suppressed via reduced CYP96B4 expression but not via the GA pathway. This research provides candidate gene‐editing targets to breed elite rice varieties.  相似文献   
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Co‐Co3O4/carbon nanotube/carbon foam (Co‐Co3O4/CNT/CF) nanocomposites were prepared by soaking melamine foam into a solution of Co(NO3)2·6H2O, followed by calcination in N2 and air in sequence. The obtained Co‐Co3O4/CNT/CF nanocomposites were characterized with scanning electron microscopy and cyclic voltammetry. It was found that Co3O4 nanoparticles were grown on the external of CF successfully, while CNTs were grown on the surfaces of CF in a large amount, which further improved the electrical conductivity of the. The prepared Co‐Co3O4/CNT/CF nanocomposites were then used to construct nonenzymatic sensor to detect glucose in alkaline solution. The sensor showed detection range from 1.2 μM to 2.29 mM with a detection limit of 0.4 μM (S/N =3) and a high sensitivity of 637.5 μA?1 cm?2. The developed sensor also showed an instant response, favorable reproducibility, and high selectivity. The results attest that Co‐Co3O4/CNT/CF composites have great potential in the development of nonenzymatic sensors for glucose.  相似文献   
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旨在研究乙醇对山羊瘤胃液与水稻秸秆厌氧共培养的影响。利用频繁传代的体外发酵技术和高通量测序方法,分析了短链脂肪酸(SCFA)产量和细菌群落的变化。结果表明,经体外培养传代8次的稻秸发酵液的总短链脂肪酸产量显著高于瘤胃液(P<0.01);与未添加乙醇的稻秸发酵液相比,添加乙醇显著提高了乙酸、戊酸和己酸的比例,降低了丙酸和丁酸的比例(P<0.01),总SCFA产量及异丁酸和异戊酸比例无显著差异。与瘤胃液相比,稻秸发酵液的拟杆菌门(Bacteroidetes)相对丰度下降,厚壁菌门(Firmicutes)相对丰度升高(P<0.05),且添加乙醇显著提高了厚壁菌门和放线菌门(Actinobacteria)的相对丰度(P<0.05);添加乙醇使双歧杆菌属(Bifidobacterium)、未定性的毛螺菌属(unidentified Lachnospiraceae)、产琥珀酸菌属(Succiniclasticum)、脱硫弧菌属(Desulfovibrio)和未定性的梭菌属(unidentified Clostridiales)的相对丰度显著升高(P<0.05)。乙醇使稻秸发酵液的显著性差异物种(Biomarker)增加;稻秸发酵液与瘤胃液亲缘关系较近,而添加乙醇显著改变了细菌区系;短链脂肪酸比例在稻秸发酵液细菌群落多样性中具有重要作用。研究表明,体外频繁传代和添加乙醇可以提高稻秸发酵液的乙酸、戊酸和己酸产量,乙醇改变了稻秸发酵液的细菌群落结构。  相似文献   
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Having a comprehensive understanding of population structure, genetic differentiation and demographic history is important for the conservation and management of threatened species. High‐throughput sequencing (HTS) provides exciting opportunities to address a wide range of factors for conservation genetics. Here, we generated HTS data and identified 266,884 high‐quality single nucleotide polymorphisms from 82 individuals of Cupressus chengiana, to assess population genomics across the species' full range, comprising the Daduhe River (DDH), Minjiang River (MJR) and Bailongjiang River (BLJ) catchments in western China. admixture , principal components analysis and phylogenetic analyses indicated that each region contains a distinct lineage, with high levels of differentiation between them (DDH, MJR and BLJ lineages). MJR was newly distinguished compared to previous surveys, and evidence including coalescent simulations supported a hybrid origin of MJR during the Quaternary. Each of these three lineages should be recognized as an evolutionarily significant unit (ESU), due to isolation, differing genetic adaptations and different demographic history. Currently, each ESU faces distinct threats, and will require different conservation strategies. Our work shows that population genomic approaches using HTS can reconstruct the complex evolutionary history of threatened species in mountainous regions, and hence inform conservation efforts, and contribute to the understanding of high biodiversity in mountains.  相似文献   
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