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101.
选用霍乱弧菌EL-Tor生物型35A3菌株(血清稻叶型)以EDTA-溶菌酶法与超速离心法提取其外膜蛋白,并将聚丙烯酰胺凝胶电泳后一条蛋白主区带分离。SDS-聚丙烯酰胺凝胶电泳测得该蛋白主区带的分子量为25kD,免疫电泳显示一条线,免疫双扩试验表明,不同的霍乱弧菌菌株均有该蛋白抗原存在。  相似文献   
102.
为构建便捷的马铃薯(Solanum tuberosum)耐荫性综合评价体系并发掘耐荫种质, 以35个马铃薯品种(系)为实验材料, 测定块茎膨大期遮荫下植株叶片叶绿素含量、光合能力和叶绿素荧光等光合参数及收获后块茎单株产量和淀粉含量等指标。根据耐荫系数, 利用主成分分析法、隶属函数法、聚类分析法和逐步回归分析法进行综合评价。通过主成分分析将马铃薯耐荫性相关的13个单项光合指标转换为6个综合指标, 代表了全部信息的87.51%。以此计算各种质的隶属函数值, 并以主成分的贡献率进行加权, 最终获得所用材料耐荫性的综合评价值(D值)。根据D值聚类分析结果将35个马铃薯分为4类, 其中Eshu10和Lishu6分别为耐荫性最强和最弱的品种。通过逐步回归分析建立了马铃薯耐荫性评价数学模型: D=0.060+0.106Gs+0.214qP+0.143NPQ。同时, 用该评价体系鉴定为耐荫性强的品种(系)在遮荫后其产量和/或淀粉含量等指标减幅均低于耐荫性弱的种质, 表明该评价体系可用于快速评价和预测马铃薯种质的耐荫性。  相似文献   
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Schistosomiasis is a serious and widespread parasitic disease caused by infection with Schistosoma. Because the parasite’s eggs are primarily responsible for schistosomiasis dissemination and pathogenesis, inhibiting egg production is a potential approach to control the spread and severity of the disease. The bromodomain and extra-terminal (BET) proteins represent promising targets for the development of epigenetic drugs against Schistosoma. JQ-1 is a selective inhibitor of the BET protein family. In the present study, JQ-1 was applied to S. japonicum in vitro. By using laser confocal scanning microscopy and EdU incorporation assays, we showed that application of JQ-1 to worms in vitro affected egg laying and the development of both the male and female reproductive systems. JQ-1 also inhibited the expression of the reproductive-related genes SjPlk1 and SjNanos1 in S. japonicum. Mice infected with S. japonicum were treated with JQ-1 during egg granuloma formation. JQ-1 treatment significantly reduced the size of the liver granulomas and levels of serum alanine aminotransferase and aspartate aminotransferase in mice and suppressed both egg laying and the development of male and female S. japonicum reproductive systems in vivo. Moreover, the mRNA expression levels of some proinflammatory cytokines were decreased in the parasites. Our findings suggest that JQ-1 treatment attenuates S. japonicum egg–induced hepatic granuloma due at least in part to suppressing the development of the reproductive system and egg production of S. japonicum. These findings further suggest that JQ-1 or other BET inhibitors warrant additional study as a new approach for the treatment or prevention of schistosomiasis.  相似文献   
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The pathogenesis of age-related hearing loss (ARHL) remains unclear. OPA1 is the sole fusion protein currently known to be situated in the inner mitochondrial membrane, which is pivotal for maintaining normal mitochondrial function. While it has already been demonstrated that mutations in OPA1 may lead to hereditary deafness, its involvement in the occurrence and development of ARHL has not been previously explored. In our study, we constructed D-gal-induced senescent HEI-OC1 cells and the cochlea of C57BL/6J mice with a mutated SUMOylation site of SIRT3 using CRISPR/Cas9 technology. We found enhanced L-OPA1 processing mediated by activated OMA1, and increased OPA1 acetylation resulting from reductions in SIRT3 levels in senescent HEI-OC1 cells. Consequently, the fusion function of OPA1 was inhibited, leading to mitochondrial fission and pyroptosis in hair cells, ultimately exacerbating the aging process of hair cells. Our results suggest that the dysregulation of mitochondrial dynamics in cochlear hair cells in aged mice can be ameliorated by activating the SIRT3/OPA1 signaling. This has the potential to alleviate the senescence of cochlear hair cells and reduce hearing loss in mice. Our study highlights the significant roles played by the quantities of long and short chains and the acetylation activity of OPA1 in the occurrence and development of ARHL. This finding offers new perspectives and potential targets for the prevention and treatment of ARHL.  相似文献   
108.
Mutations of the RAS oncogene are found in around 30% of all human cancers yet direct targeting of RAS is still considered clinically impractical except for the KRASG12C mutant. Here we report that RAS-ON (RASON), a novel protein encoded by the long intergenic non-protein coding RNA 00673 (LINC00673), is a positive regulator of oncogenic RAS signaling. RASON is aberrantly overexpressed in pancreatic ductal adenocarcinoma (PDAC) patients, and it promotes proliferation of human PDAC cell lines in vitro and tumor growth in vivo. CRISPR/Cas9-mediated knockout of Rason in mouse embryonic fibroblasts inhibits KRAS-mediated tumor transformation. Genetic deletion of Rason abolishes oncogenic KRAS-driven pancreatic and lung cancer tumorigenesis in LSL-KrasG12D; Trp53R172H/+ mice. Mechanistically, RASON directly binds to KRASG12D/V and inhibits both intrinsic and GTPase activating protein (GAP)-mediated GTP hydrolysis, thus sustaining KRASG12D/V in the GTP-bound hyperactive state. Therapeutically, deprivation of RASON sensitizes KRAS mutant pancreatic cancer cells and patient-derived organoids to EGFR inhibitors. Our findings identify RASON as a critical regulator of oncogenic KRAS signaling and a promising therapeutic target for KRAS mutant cancers.Subject terms: Gastrointestinal cancer, Cancer therapy  相似文献   
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Rice eating and cooking quality(ECQ) is a major concern of breeders and consumers, determining market competitiveness worldwide. Rice grain protein content(GPC) is negatively related to ECQ,making it possible to improve ECQ by manipulating GPC. However, GPC is genetically complex and sensitive to environmental conditions; therefore, little progress has been made in traditional breeding for ECQ. Here, we report that CRISPR/Cas9-mediated knockout of genes encoding the grain storage protein gluteli...  相似文献   
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