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201.
Wang  Yue  Su  Shengnan  Chen  Guogang  Mao  Huijuan  Jiang  Ying 《Journal of Plant Growth Regulation》2021,40(3):1152-1165

Cuticular wax is an important factor that affects storage quality of fruits and vegetables. Previous studies have shown that cuticular wax of pears changes significantly during storage, whereas there are few studies on the effects of different storage methods on the wax changes and the relationship with storage quality. Cuticular wax of Korla pear stored using different methods, was measured to analyze its total wax content, chemical compositions and their relationship with storage quality. At the end of storage, the highest cuticular wax content was observed in controlled atmosphere (CA) storage and the lowest in room temperature storage. The substances of the primary components with higher contents were nonacosane, (E, E)-ɑ-farnesene, dodecan-1-ol, 1,1-dimethoxynonane, nonanal, palmitic acid, and oleic acid. Total wax content, olefins and fatty acids were most significantly with the storage quality, followed by alkanes and esters. Moreover, total wax content, wax composition and weight loss were closely related to postharvest senescence. Overall, an understanding of variations in the cuticular wax under different storage methods could provide theoretical basis for further study on the storage and preservation technology of pears.

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202.
Huang  Lihong  Fu  Qiang  Dai  Jia-Meng  Yan  Bing-Chao  Wang  Dawei  Puno  Pema-Tenzin  Yue  Jianbo 《Cell biology and toxicology》2021,37(5):695-713
Cell Biology and Toxicology - Autophagy is a conserved lysosomal degradation process, and abnormal autophagy has been associated with various pathological processes, e.g., neurodegeneration,...  相似文献   
203.
Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with unclear pathogenesis. We previously reported that syngenetic, activated lymphocyte-derived DNA (ALD-DNA) could robustly elicit macrophage activation, which plays an important role in the pathogenesis of murine lupus nephritis. In addition, extracellular HMGB1 obviously facilitated the accumulation of ALD-DNA in endosomes and promoted macrophage inflammation. While the detailed mechanism was still unknown. In this study, we found that HMGB1 could obviously change the DNA uptake pathways in macrophages. ALD-DNA alone was mainly uptake by the low efficient and unselective macropinocytosis, while extracellular HMGB1 potently promoted the more efficient and specific clathrin-/caveolin-1-dependent receptor-mediated endocytosis pathways, and led to the rapid and abundant aggregation of ALD-DNA in endosomes. This effect relied on the DNA binding ability and TLR2/TLR4 of HMGB1. Our study not only helped us to understand the promotion mechanisms of extracellular HMGB1 on ALD-DNA-induced macrophage inflammation, but also provided some clues to the pathogenesis of SLE.  相似文献   
204.
Purpose

Bio-jet fuel derived from energy crops has been promoted by governments around the world through policies such as the Carbon Offsetting and Reduction Scheme for International Aviation. The environmental impact and techno-economic analysis of bio-jet fuel are particularly pertinent to China because China is under huge pressure to reduce emissions, endeavouring to meet bio-economic goals.

Methods

An LCA study was conducted on the production of bio-jet fuel from jatropha and castor by estimating the well-to-wake emissions and its economic impact. The functional unit was 1 MJ of bio-jet fuel, and field survey data was used in inventory analysis. A scenario analysis was performed to measure diverse conditions, including the planting conditions, planting regions, allocation methods, and hydrogen sources. A techno-economic analysis that combined the production costs and co-product credits was performed to calculate the minimum bio-jet fuel selling price (MJSP) based on a plant capacity of 2400 metric tonnes of feedstock per day.

Results and discussion

Compared to the environmental impacts to the fossil jet fuel, the use of biofuel would reduce the majority environmental impacts by 36–85%, when a 1:1 displacement of fossil jet fuel is considered, though the human toxicity potential impact was 100% higher. The scenario analysis indicated that (i) planting castor in harsh and unevenly distributed conditions and jatropha in stable or fertile conditions can leverage their respective advantage; (ii) the global warming potential (GWP) from castor planting in the region of north-east China ranges from 34 to 48 g CO2 eq/MJ; (iii) the GWP produced through the steam methane reforming process can be reduced by 16–17%, using advances in technological processes. The MJSP for fuel produced from jatropha and castor under the basic scenario is estimated to be 5.68 and 4.66 CNY/kg, respectively, which falls within the current market price range of 4.5–7.5 CNY/kg.

Conclusions

Bio-jet fuel from jatropha and castor oilseeds offers potential environmental benefits if they can reduce fossil jet fuel on an energy-equivalent basis. However, these benefits are likely to be reduced by the rebound effect of the fuel market. Future research is needed to better understand the magnitude of the rebound effect in China and what policy interventions can be implemented to alleviate it. Scenario analysis demonstrated the feasibility and potential of bio-jet fuel development from multiple perspectives and technological progress are conducive to the realization of environmental protection policies.

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205.
206.
BackgroundIn mammals, early pregnancy is a critical vulnerable period during which complications may arise, including pregnancy failure. Establishment of a maternal endometrial acceptance phenotype is a prerequisite for semiheterogeneous embryo implantation, comprising the rate‐limiting step of early pregnancy.MethodsConfocal fluorescence, immunohistochemistry and western blot for nuclear and cytoplasmic protein were used to examine the activation of yes‐associated protein (YAP) in uterine tissue and primary endometrial cells. The target binding between miR16a and YAP was verified by dual‐luciferase reporter gene assay. The mouse pregnancy model and pseudopregnancy model were used to investigate the role of YAP in the maternal uterus during early pregnancy in vivo.ResultsWe showed that YAP translocates into the nucleus in the endometrium of cattle and mice during early pregnancy. Mechanistically, YAP acts as a mediator of ECM rigidity and cell density, which requires the actomyosin cytoskeleton and is partially dependent on the Hippo pathway. Furthermore, we found that the soluble factor IFNτ, which is a ruminant pregnancy recognition factor, also induced activation of YAP by reducing the expression of miR‐16a.ConclusionsThis study revealed that activation of YAP is necessary for early pregnancy in bovines because it induced cell proliferation and established an immunosuppressive local environment that allowed conceptus implantation into the uterine epithelium.  相似文献   
207.
ObjectivesNLRP3 inflammasome is a critical part of the innate immune system and plays an important role in a variety of inflammatory diseases. However, the effects of NLRP3 inflammasome on periodontitis have not been fully studied.Materials and methodsWe used ligature‐induced periodontitis models of NLRP3 knockout mice (NLRP3KO) and their wildtype (WT) littermates to compare their alveolar bone phenotypes. We further used Lysm‐Cre/RosanTnG mouse to trace the changes of Lysm‐Cre+ osteoclast precursors in ligature‐induced periodontitis with or without MCC950 treatment. At last, we explored MCC950 as a potential drug for the treatment of periodontitis in vivo and in vitro.ResultsHere, we showed that the number of osteoclast precursors, osteoclast differentiation and alveolar bone loss were reduced in NLRP3KO mice compared with WT littermates, by using ligature‐induced periodontitis model. Next, MCC950, a specific inhibitor of the NLRP3 inflammasome, was used to inhibit osteoclast precursors differentiation into osteoclast. Further, we used Lysm‐Cre/RosanTnG mice to demonstrate that MCC950 decreases the number of Lysm‐Cre+ osteoclast precursors in ligature‐induced periodontitis. At last, treatment with MCC950 significantly suppressed alveolar bone loss with reduced IL‐1β activation and osteoclast differentiation in ligature‐induced periodontitis.ConclusionOur findings reveal that NLRP3 regulates alveolar bone loss in ligature‐induced periodontitis by promoting osteoclastic differentiation.  相似文献   
208.
Zhang  Ling  Wang  Yingzhe  Li  Tong  Qiu  Hongmei  Xia  Zhengjun  Dong  Yingshan 《Transgenic research》2021,30(1):51-62

Soybean has a palaeopolyploid genome with nearly 75% of the genes present in multiple copies. Although the CRISPR/Cas9 system has been employed in soybean to generate site-directed mutagenesis, a systematical assessment of mutation efficiency of the CRISPR/Cas9 system for the multiple-copy genes is still urgently needed. Here, we successfully optimize one sgRNA CRISPR/Cas9 system in soybean by testing the efficiency, pattern, specificity of the mutations at multiple loci of GmFAD2 and GmALS. The results showed that simultaneous site-directed mutagenesis of two homoeologous loci by one sgRNA, the mutation frequency in the T0 generation were 64.71% for GmPDS, 60.0% for GmFAD2 and 42.86% for GmALS, respectively. The chimeric and heterozygous mutations were dominant types. Moreover, association of phenotypes with mutation pattern at target loci of GmPDS11 and GmPDS18 could help us further demonstrate that the CRISPR/Cas9 system can efficiently generate target specific mutations at multiple loci using one sgRNA in soybean, albeit with a relatively low transformation efficiency.

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209.
Liu  Jin Yue  Sheng  Ze Wen  Hu  Yu Qi  Liu  Qi  Qiang  Sheng  Song  Xiao Ling  Liu  Biao 《Transgenic research》2021,30(1):105-119
Transgenic Research - The releasing of transgenic soybeans (Glycine max (L.) Merr.) into farming systems raises concerns that transgenes might escape from the soybeans via pollen into...  相似文献   
210.
Bio3D is a family of R packages for the analysis of biomolecular sequence, structure, and dynamics. Major functionality includes biomolecular database searching and retrieval, sequence and structure conservation analysis, ensemble normal mode analysis, protein structure and correlation network analysis, principal component, and related multivariate analysis methods. Here, we review recent package developments, including a new underlying segregation into separate packages for distinct analysis, and introduce a new method for structure analysis named ensemble difference distance matrix analysis (eDDM). The eDDM approach calculates and compares atomic distance matrices across large sets of homologous atomic structures to help identify the residue wise determinants underlying specific functional processes. An eDDM workflow is detailed along with an example application to a large protein family. As a new member of the Bio3D family, the Bio3D‐eddm package supports both experimental and theoretical simulation‐generated structures, is integrated with other methods for dissecting sequence‐structure–function relationships, and can be used in a highly automated and reproducible manner. Bio3D is distributed as an integrated set of platform independent open source R packages available from: http://thegrantlab.org/bio3d/ .  相似文献   
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