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991.
Dendrolimus spp. are important destructive pests of conifer forests, and Dendrolimus punctatus Walker (Lepidoptera; Lasiocampidae) is the most widely distributed Dendrolimus species. During periodic outbreaks, this species is said to make “fire without smoke” because large areas of pine forest can be quickly and heavily damaged. Yet, little is known about the molecular mechanisms that underlie the unique ecological characteristics of this forest insect. Here, we combined Pacific Biosciences (PacBio) RSII single‐molecule long reads and high‐throughput chromosome conformation capture (Hi‐C) genomics‐linked reads to produce a high‐quality, chromosome‐level reference genome for D. punctatus. The final assembly was 614 Mb with contig and scaffold N50 values of 1.39 and 22.15 Mb, respectively, and 96.96% of the contigs anchored onto 30 chromosomes. Based on the prediction, this genome contained 17,593 protein‐coding genes and 56.16% repetitive sequences. Phylogenetic analyses indicated that D. punctatus diverged from the common ancestor of Hyphantria cunea, Spodoptera litura and Thaumetopoea pityocampa ~ 108.91 million years ago. Many gene families that were expanded in the D. punctatus genome were significantly enriched for the xenobiotic biodegradation system, especially the cytochrome P450 gene family. This high‐quality, chromosome‐level reference genome will be a valuable resource for understanding mechanisms of D. punctatus outbreak and host resistance adaption. Because this is the first Lasiocampidae insect genome to be sequenced, it also will serve as a reference for further comparative genomics.  相似文献   
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Exosomes hold great potential to deliver therapeutic reagents for cancer treatment due to its inherent low antigenicity. However, several technical barriers, such as low productivity and ineffective cancer targeting, need to be overcome before wide clinical applications. The present study aims at creating a new biomanufacturing platform of cancer‐targeted exosomes for drug delivery. Specifically, a scalable, robust, high‐yield, cell line based exosome production process is created in a stirred‐tank bioreactor, and an efficient surface tagging technique is developed to generate monoclonal antibody (mAb)‐exosomes. The in vitro characterization using transmission electron microscopy, NanoSight, and western blotting confirm the high quality of exosomes. Flow cytometry and confocal laser scanning microscopy demonstrate that mAb‐exosomes have strong surface binding to cancer cells. Furthermore, to validate the targeted drug delivery efficiency, romidepsin, a histone deacetylase inhibitor, is loaded into mAb‐exosomes. The in vitro anti‐cancer toxicity study shows high cytotoxicity of mAb‐exosome‐romidepsin to cancer cells. Finally, the in vivo study using tumor xenograft animal model validates the cancer targeting specificity, anti‐cancer efficacy, and drug delivery capability of the targeted exosomes. In summary, new techniques enabling targeted exosomes for drug delivery are developed to support large‐scale animal studies and to facilitate the translation from research to clinics.  相似文献   
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The pandemic outbreaks of coronavirus disease 2019 (COVID‐19), caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), spread all over the world in a short period of time. Efficient identification of the infection by SARS‐CoV‐2 has been one of the most important tasks to facilitate all the following counter measurements in dealing with the infectious disease. In Taiwan, a COVID‐19 Open Science Platform adheres to the spirit of open science: sharing sources, data, and methods to promote progress in academic research while corroborating findings from various disciplines has established in mid‐February 2020, for collaborative research in support of the development of detection methods, therapeutics, and a vaccine for COVID‐19. Research priorities include infection control, epidemiology, clinical characterization and management, detection methods (including viral RNA detection, viral antigen detection, and serum antibody detection), therapeutics (neutralizing antibody and small molecule drugs), vaccines, and SARS‐CoV‐2 pathogenesis. In addition, research on social ethics and the law are included to take full account of the impact of the COVID‐19 virus.  相似文献   
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Cypermethrin (CP) is widely used for controlling agricultural and indoor vermin. Previous studies have reported the stereoselective difference of CP in biological activities. However, little is known about their potential mechanisms between metabolic phenotypes and endocrine-disrupting effects. Herein, nuclear magnetic resonance (NMR)-based metabolomics combining metabolite identification and pathway analysis were applied to evaluate the stereoselective metabolic cdisorders induced by CP isomers in human adrenocortical carcinoma cells (H295R) culture medium. Then, gene expression levels related to disturbed metabolic pathways were assessed to verify according to metabolic phenotypes. Metabolomics profiles showed that [(S)-cyano(3-phenoxyphenyl)methyl](1R,3R)-3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropane-1-carboxylate [(1R,3RS)-CP] induced the most significant changes in metabolic phenotypes than did the other stereoisomers. There are 10 differential metabolites (isoleucine, valine, leucine, ethanol, alanine, acetate, aspartate, arginine, lactate, and glucose) as well as two significantly disturbed pathways, including “pyruvate metabolism” and “alanine, aspartate, and glutamate metabolism,” that were confirmed in H295R cells culture medium of (1R,3RS)-CP compared with other stereoisomers. Polymerase chain reaction (PCR) array also confirmed the results of metabolomics. Our results can help to understand the potential mechanisms between the isomer selectivity in metabolic phenotypes and endocrine-disrupting effects. Data provided here not only lend authenticity to the cautions issued by the scientists and researchers but also offer a solution for the balance between environment and political regulations.  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   
998.
Xiang  Ping  Sun  Youwen  Fang  Zhiqing  Yan  Keqiang  Fan  Yidong 《Mammalian genome》2020,31(7-8):197-204
Mammalian Genome - Prostate cancer, the second most common cancer among male adults, affects millions globally. We sought to investigate the expression and contribution of Eukaryotic translation...  相似文献   
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