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61.
Xiao-Long Lin Yan-Min Zhao Li-Ping Yan Wen-Bin Liu Wen-Jun Bu Xin-Hua Wang Chen-Guang Zheng 《Zoologica scripta》2022,51(1):119-132
Evolutionary analysis of Prodiamesinae has long been impeded by lack of information, and its phylogenetic relationship with Orthocladiinae remains questionable. Here, ten complete mitochondrial genomes (mitogenomes) of Orthocladiinae sensu lato were newly sequenced, including three Prodiamesinae species and seven Orthocladiinae species. Coupled with published mitogenomes, a total of 12 mitogenomes of Orthocladiinae sensu lato were selected for a comparative mitogenomic analysis and phylogenetic reconstruction. Mitogenomes of Orthocladiinae sensu lato are conserved in structure, and all genes arrange the same gene order as the ancestral insect mitogenome. Nucleotide composition is highly biased, and the control region displayed the highest A + T content. All protein-coding genes are under purifying selection, and the ATP8 evolves at the fastest rate. In addition, the mitogenomes of Orthocladiinae sensu lato are highly conserved, and they are practically useful for phylogenetic inference, suggesting a re-classification of Orthocladiinae by sinking Prodiamesinae as a subgroup of Orthocladiinae. 相似文献
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Kai Wu Yamei Hu Kanglu Yan Yu Qi Chunyang Zhang Dengyan Zhu Donglei Liu Song Zhao 《Journal of cellular physiology》2020,235(2):1247-1258
It is well known that the acquisition of chemoresistance is a major obstacle for the effective treatment of human cancers. It is reported that microRNAs (miRNAs) are implicated in chemotherapy resistance of various malignancies. miR-10b was previously proved as an oncogene in multiple malignancies, including esophageal cancer. However, its biological significance in regulating cisplatin (DDP) resistance in esophageal cancer is still elusive. Here, we observed that miR-10b expression was upregulated and peroxisome proliferator-activated receptor-γ (PPARγ) expression was downregulated in esophageal cancer tumor tissues and cells. PPARγ was proved as a functional target of miR-10b. Moreover, suppression of miR-10b enhanced the chemosensitivity of esophageal cancer cells to DDP in vitro and in vivo. In addition, PPARγ-mediated DDP sensitivity was weakened by miR-10b overexpression. Furthermore, miR-10b-activated AKT/mTOR/p70S6K signaling pathway through targeting PPARγ. Inactivation of AKT/mTOR/p70S6K by AKT inhibitor (GSK690693) attenuated miR-10b-induced DDP resistance in esophageal cancer cells. Taken together these observation, miRNA-10b-mediated PPARγ inhibition enhanced DDP resistance by activating the AKT/mTOR/P70S6K signaling in esophageal cancer, suggesting a potential target to improve therapeutic response of patients with esophageal cancer to DDP. 相似文献
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Following an extensive review of the literature, we further analyze the published data to examine the health effects of indoor exposure to particulate matter (PM) of outdoor origin. We obtained data on all-cause, cardiovascular, and respiratory mortality per 10 μg/m3 increase in outdoor PM10 or PM2.5; the infiltration factors for buildings; and estimated time spent outdoors by individuals in the United States, Europe, China, and globally. These data were combined log-linear exposure–response model to estimate the all-cause, cardiovascular, and respiratory mortality of exposure to indoor PM pollution of outdoor origin. Indoor PM pollution of outdoor origin is a cause of considerable mortality, accounting for 81% to 89% of the total increase in mortality associated with exposure to outdoor PM pollution for the studied regions. The findings suggest that enhancing the capacity of buildings to protect occupants against exposure to outdoor PM pollution has significant potential to improve public health outcomes. 相似文献
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Loss of allosteric control but retention of the bifunctional catalytic competence of a fusion protein formed by excision of 260 base pairs from the 3' terminus of pheA from Erwinia herbicola. 下载免费PDF全文
A bifunctional protein denoted as the P protein and encoded by pheA is widely present in purple gram-negative bacteria. This P protein carries catalytic domains that specify chorismate mutase (CM-P) and prephenate dehydratase. The instability of a recombinant plasmid carrying a pheA insert cloned from Erwinia herbicola resulted in a loss of 260 bp plus the TAA stop codon from the 3' terminus of pheA. The plasmid carrying the truncated pheA gene (denoted pheA*) was able to complement an Escherichia coli pheA auxotroph. pheA* was shown to be a chimera composed of the residual 5' part of pheA (901 bp) and a 5-bp fragment from the pUC18 vector. The new fusion protein (PheA*) retained both chorismate mutase and prephenate dehydratase activities. PheA* had a calculated subunit molecular weight of 33,574, in comparison to the 43,182-molecular-weight subunit size of PheA. The deletion did not affect the ability of PheA* to assume the native dimeric configuration of PheA. Both the CM-P and prephenate dehydratase components of PheA* were insensitive to L-phenylalanine inhibition, in contrast to the corresponding components of PheA. L-Phenylalanine protected both catalytic activities of PheA from thermal inactivation, and this protective effect of L-phenylalanine upon the PheA* activities was lost. PheA* was more stable than PheA to thermal inactivation; this was more pronounced for prephenate dehydratase than for CM-P. In the presence of dithiothreitol, the differential resistance of PheA* prephenate dehydratase to thermal inactivation was particularly striking.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Abstract Extracts of hairpencils ffom male cotton bollworm moth were analyzed by capillary gas chromatography, acid methanolysis, and GC-MS. Ten components have been identified as: 14; OH, 14: Ac, 14: COOH, 211–16: OH, 16: OH, 16: Ac, 16: COOH, 18: OH, 18: Ac, and 18: COOH. Based on the statistics of titer of each chemical, the total amount of three saturated alcohols is over 75%. The amounts of the chemicals in the hairpencils are related to the age of males. There are no chemicals identified in the extracts from males less than 10 h after eclosion, then the quantity of compounds increased rapidly during 48 h after adult eclosion. After 5 days, the quantity decreased. 相似文献
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