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131.
The aim of this study was to explore the effects of platelet‐rich plasma on gingipain‐caused changes in cell morphology and apoptosis of osteoblasts. Mouse osteoblasts MC3T3‐E1 cells were treated with gingipain extracts from Porphyromonas gingivalis in the presence or absence of platelet‐rich plasma. Apoptosis was detected with terminal deoxynucleotidyl transferase‐mediated dUTP nick‐end labeling staining. F‐actin was determined by phalloidin‐fluorescent staining and observed under confocal microscopy. Western blot analysis was used to detect integrin β1, F‐actin, and G‐actin protein expressions. A knocking down approach was used to determine the role of integrin β1. The platelet‐rich plasma protected osteoblasts from gingipain‐induced apoptosis in a dose‐dependent manner, accompanied by upregulation of integrin β1. Platelet‐rich plasma reversed the loss of F‐actin integrity and decrease of F‐actin/G‐actin ratio in osteoblasts in the presence of gingipains. By contrast, the effects of platelet‐rich plasma were abrogated by knockdown of integrin β1. The platelet‐rich plasma failed to reduce cell apoptosis and reorganize the cytoskeleton after knockdown of integrin β1. In conclusion, platelet‐rich plasma inhibits gingipain‐induced osteoblast apoptosis and actin cytoskeleton disruption by upregulating integrin β1 expression.  相似文献   
132.
The rice stem borer, Chilo suppressalis, is one of the most damaging insect pests to rice production worldwide. Although C. suppressalis has been the focus of numerous studies examining cold tolerance and diapause, plant–insect interactions, pesticide targets and resistance, and the development of RNAi‐mediated pest management, the absence of a high‐quality genome has limited deeper insights. To address this limitation, we generated a draft C. suppressalis genome constructed from both Illumina and PacBio sequences. The assembled genome size was 824.35 Mb with a contig N50 of 307 kb and a scaffold N50 of 1.75 Mb. Hi‐C scaffolding assigned 99.2% of the bases to one of 29 chromosomes. Based on universal single‐copy orthologues (BUSCO), the draft genome assembly was estimated to be 97% complete and is predicted to encompass 15,653 protein‐coding genes. Cold tolerance is an extreme survival strategy found in animals. However, little is known regarding the genetic basis of the winter ecology of C. suppressalis. Here, we focused our orthologous analysis on those gene families associated with animal cold tolerance. Our finding provided the first genomic evidence revealing specific cold‐tolerant strategies in C. suppressalis, including those involved in glucose‐originated glycerol biosynthesis, triacylglycerol‐originated glycerol biosynthesis, fatty acid synthesis and trehalose transport‐intermediate cold tolerance. The high‐quality C. suppressalis genome provides a valuable resource for research into a broad range of areas in molecular ecology, and subsequently benefits developing modern pest control strategies.  相似文献   
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Guo  Kaiqiang  Cao  Yin  Li  Zan  Zhou  Xiaoxiao  Ding  Rong  Chen  Kejing  Liu  Yan  Qiu  Yingkun  Wu  Zhen  Fang  Meijuan 《Amino acids》2020,52(5):793-809
Amino Acids - Glycine plays a key role in rapidly proliferating cancer cells such as A549 cells. Targeting glycine metabolism is considered as a potential means for cancer treatment. However, the...  相似文献   
135.
Yang  Yuping  Qiu  Yue  Liu  Xu  Liu  Yanhua  Yin  Yaling  Li  Peng 《Amino acids》2020,52(4):511-521
Amino Acids - Kinase-targeted therapy has been widely used as a lifesaving strategy for cancer patients. However, many patients treated with targeted cancer drugs are clinically observed to rapidly...  相似文献   
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Chimonanthus salicifolius, a member of the Calycanthaceae of magnoliids, is one of the most famous medicinal plants in Eastern China. Here, we report a chromosome‐level genome assembly of Csalicifolius, comprising 820.1 Mb of genomic sequence with a contig N50 of 2.3 Mb and containing 36 651 annotated protein‐coding genes. Phylogenetic analyses revealed that magnoliids were sister to the eudicots. Two rounds of ancient whole‐genome duplication were inferred in the Csalicifolious genome. One is shared by Calycanthaceae after its divergence with Lauraceae, and the other is in the ancestry of Magnoliales and Laurales. Notably, long genes with > 20 kb in length were much more prevalent in the magnoliid genomes compared with other angiosperms, which could be caused by the length expansion of introns inserted by transposon elements. Homologous genes within the flavonoid pathway for Csalicifolius were identified, and correlation of the gene expression and the contents of flavonoid metabolites revealed potential critical genes involved in flavonoids biosynthesis. This study not only provides an additional whole‐genome sequence from the magnoliids, but also opens the door to functional genomic research and molecular breeding of Csalicifolius.  相似文献   
138.
施硼和赤霉素对‘李广杏’坐果率及果实品质的影响   总被引:1,自引:0,他引:1  
该研究以8年生盛果期的‘李广杏’植株为试材,于花蕾膨大期喷施0.1%(P1)、0.3%(P2)和0.5%(P3)硼砂和盛花初期喷施50(C1)、100(C2)和150 mg/L(C3)赤霉素,测定不同处理下李广杏的坐果率、果实品质及营养生长指标的变化,并用主成分分析不同处理的效果进行综合评价,为敦煌寒旱区‘李广杏’的栽培提供理论依据。结果表明:(1)‘李广杏’叶面积增长量在C1浓度处理下显著高于CK,不同浓度的硼处理对其均具有抑制作用,但C1、P2浓度下新稍生长量高于其他处理。(2)适宜浓度的硼和赤霉素处理可一定程度减少‘李广杏’花的败育率,从而有效提高果树的坐果率,其中硼处理以P3浓度下最优,但P3与P2处理下坐果率无显著差异,赤霉素处理以C2浓度下最优。(3)适宜浓度硼和赤霉素能够明显提高‘李广杏’果实品质,C1浓度处理下的果实糖酸比、可溶性固形物含量显著高于CK,P2处理下的果实维生素C、可滴定酸含量显著高于其他处理;适宜浓度赤霉素和硼对果实的单果重、果形指数、侧径有明显的促进作用。(4)主成分分析结果显示,各处理效果的综合得分由高到低依次为P2(1.20)>C2(0.91)>P1(0.13)>C1(-1.01)>CK(-1.68)>P3(-2.13)>C3(-7.76);果实可溶性糖、可溶性蛋白、糖酸比等主成分占比较高,可作为评价‘李广杏’果实品质的重要依据。研究发现,花期喷施适宜浓度的硼和赤霉素可有效提高‘李广杏’果树的生长状况、坐果率及果实品质,且甘肃敦煌地区以花蕾膨大期喷施0.3%硼和盛花初期喷施100 mg/L赤霉素效果最佳。  相似文献   
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通过整理鉴定四川大学自然博物馆馆藏的100多年间采自四川省的1万余号蝶类标本,最早的四川蝶类标本(宽带凤蝶西部亚种Papilio nephelus chaon)采于1910年,结合文献和专著资料,参考《中国蝶类志》的分类系统,得到四川省蝶类644种,隶属于12科240属。其中,蛱蝶科Nymphalidae 162种、弄蝶科Hesperiidae 125种、眼蝶科Satyridae 114种、灰蝶科Lycaenidae 100种、粉蝶科Pieridae 59种、凤蝶科Papilionidae 45种、蚬蝶科Riodinidae 14种、绢蝶科Parnassiidae 11种、斑蝶科Danaidae 8种、环蝶科Amathusiidae 4种、喙蝶科Libytheidae 1种、珍蝶科Acraeidae 1种。四川省蝶类物种组成丰富,其中,蛱蝶科、弄蝶科、眼蝶科和灰蝶科物种数均超过或达到100种。建议在全省范围内选择不同生境建立长期监测点,持续监测蝶类物种多样性分布及变化情况,这对于保护全省生态环境和维持生物多样性都是至关重要的。建议尽快开展相关研究,包括四川省蝶类的经典分类学、系统发育及区系、生物地理学、生态学、行为学和进化生态学等研究。  相似文献   
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