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L. Zheng Z. Y. Peng Q. Q. Jiao Y. Wang F. Bian S. J. Qu S. B. Wan Y. P. Bi 《Russian Journal of Plant Physiology》2016,63(5):673-677
The demand for INSULIN is increasing rapidly along with the increased number of diabetic patients. Using the CRE/loxP system, we developed a selective marker-free system without crossing to produce PROINSULIN in transgenic plant. In frame of this approach, the induced promoter pRD29A was isolated from Arabidopsis. The CRE recombinase gene was placed under the control of pRD29A between two loxP recombination sites together with the selective NPTII gene. Furthermore, the binary vector with CRE recombinase and PROINSULIN was constructed and introduced into tobacco (Nicotiana tabacum L.) by Agrobacterium-mediated transformation. Gene excision was used to remove the sequence between the two loxP sites at the presence of 200 mM NaCl. PCR analysis showed that self-excision occurred in several T0 transgenic plants. Transgenic plants without any marker gene successfully expressed PROINSULIN. This auto-excision strategy provides efficient means of removing the selectable marker gene from transgenic plants. It is an efficient method for producing bio-safe recombinant protein and other valuable substances in plants. 相似文献
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The Varroa mite,(Varroa destructor),is the worst threat to honey bee health worldwide.To explore the possibility of using RNA interference to control this pest, we determined the effects of knocking down various genes on Varroa mite survival and reproduction.Double-stranded RNA (dsRNA)of six candidate genes (Da,Pros26S,RpL8, RpL11,RpPO and RpS13)were synthesized and each injected into Varroa mites,then mite survival and reproduction were assessed.Injection of dsRNA for Da (Daughterless)and Pros26S (Gene for proteasome 26S subunit adenosine triphosphatase)caused a significant reduction in mite survival,with 3.57%±1.94% and 30.03%±11.43% mites surviving at 72 h post-inj ection (hpi),respectively.Control mites injected with green fluorescent protein (GFP)-dsRNA showed survival rates of 81.95%±5.03% and 82.36 ±2.81%,respectively. Injections of dsRNA for four other genes (RpL8,RpL11,RpPO and RpS13)did not affect survival significantly,enabling us to assess their effect on Varroa mite reproduction.The number of female offspring per mite was significantly reduced for mites injected with dsRNA of each of these four genes compared to their GFP-dsRNA controls.Knockdown of the target genes was verified by real-time polymerase chain reaction for two genes important for reproduction (RpL8,RpL11)and one gene important for survival (Pros26S). In conclusion,through RNA interference,we have discovered two genes important for mite survival and four genes important for mite reproduction.These genes could be explored as possible targets for the control of Varroa destructor in the future. 相似文献
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为探讨针刀联合曲安奈德、正清风痛宁、利多卡因治疗肩周炎的临床疗效及安全性分析,本研究选取2016年1月至2017年12月来东南大学附属中大医院疼痛科就诊肩周炎患者120例,随机数字表法分为药物治疗组40例(曲安奈德+正清风痛宁+利多卡因+臭氧治疗),针刀治疗组40例,综合治疗组40例(曲安奈德+正清风痛宁+利多卡因+臭氧+针刀治疗),对比分析各组治疗前后肩关节功能评分、视觉模拟评分法(visual analogue score, VAS)评分、不良反应发生率。结果显示,组内比较,3组治疗后VAS和肩关节功能评分与治疗前比较,差异具有统计学意义(p<0.001)。组间比较,治疗前3组VAS和肩关节功能评分比较,差异不具有统计学意义;综合治疗组各时间点VAS评分均低于药物及针刀治疗组,综合治疗组肩关节功能评分在治疗后1个月和2个月高于药物及针刀治疗组,差异具有统计学意义(p<0.001)。3组的不良反应发生率,差异不具有统计学意义(p>0.05)。综上所述,针刀治疗联合曲安奈德、正清风痛宁、利多卡因及臭氧在关节腔及关节周围注射治疗肩周炎安全有效,值得在临床中推广应用。 相似文献
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Xuting Bian Tianyao Liu Mei Zhou Gang He Yuanyuan Ma Youxing Shi Yunjiao Wang Hong Tang Xia Kang Mingyu Yang Jan‐ke Gustafsson Xiaotang Fan Kanglai Tang 《Journal of cellular and molecular medicine》2019,23(11):7406-7416
Achilles tendon injury is one of the challenges of sports medicine, the aetiology of which remains unknown. For a long time, estrogen receptor β (ERβ) has been known as a regulating factor of the metabolism in many connective tissues, such as bone, muscle and cartilage, but little is known about its role in tendon. Recent studies have implicated ERβ as involved in the process of tendon healing. Tendon‐derived stem cells (TDSCs) are getting more and more attention in tendon physiological and pathological process. In this study, we investigated how ERβ played a role in Achilles tendon healing. Achilles tendon injury model was established to analyse how ERβ affected on healing process in vivo. Cell proliferation assay, Western blots, qRT‐PCR and immunocytochemistry were performed to investigate the effect of ERβ on TDSCs. Here, we showed that ERβ deletion in mice resulted in inferior gross appearance, histological scores and, most importantly, increased accumulation of adipocytes during the early tendon healing which involved activation of peroxisome proliferator‐activated receptor γ (PPARγ) signalling. Furthermore, in vitro results of ours confirmed that the abnormity might be the result of abnormal TDSC adipogenic differentiation which could be partially reversed by the treatment of ERβ agonist LY3201. These data revealed a role of ERβ in Achilles tendon healing for the first time, thereby providing a new target for clinical treatment of Achilles tendon injury. 相似文献
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Ziran Zhao Feidan Gu Haixia Rao Senyun Ye Zhiwei Liu Zuqiang Bian Chunhui Huang 《Liver Transplantation》2019,9(3)
Metal halide perovskite solar cells (PSCs) have emerged as promising candidates for photovoltaic technology with their power conversion efficiencies over 23%. For prototypical organic–inorganic metal halide perovskites, their intrinsic instability poses significant challenges to the commercialization of PSCs. Recently, the scientific community has done tremendous work in composition engineering to develop more robust light‐absorbing layers, including mixed‐ion hybrid perovskites, low‐dimensional hybrid perovskites, and all‐inorganic perovskites. This review provides an overview of the impact of these perovskites on the efficiency and long‐term stability of PSCs. 相似文献
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Qiang‐Qiang Xiong Tian‐Hua Shen Lei Zhong Chang‐Lan Zhu Xiao‐Song Peng Xiao‐Peng He Jun‐Ru Fu Lin‐Juan Ouyang Jian‐Min Bian Li‐Fang Hu Xiao‐Tang Sun Jie Xu Hui‐Ying Zhou Hao‐Hua He Xiao‐Rong Chen 《Physiologia plantarum》2019,167(4):564-584
Abrupt drought–flood alternation (T1) is a meteorological disaster that frequently occurs during summer in southern China and the Yangtze river basin, often causing a significant loss of rice production. In this study, the response mechanism of yield decline under abrupt drought–flood alternation stress at the panicle differentiation stage was analyzed by looking at the metabolome, proteome as well as yield and physiological and biochemical indexes. The results showed that drought and flood stress caused a decrease in the yield of rice at the panicle differentiation stage, and abrupt drought–flood alternation stress created a synergistic effect for the reduction of yield. The main reason for the decrease of yield per plant under abrupt drought–flood alternation was the decrease of seed setting rate. Compared with CK0 (no drought and no flood), the net photosynthetic rate and soluble sugar content of T1 decreased significantly and its hydrogen peroxidase, superoxide dismutase, peroxidase activity increased significantly. The identified differential metabolites and differentially expressed proteins indicated that photosynthesis metabolism, energy metabolism pathway and reactive oxygen species response have changed strongly under abrupt drought–flood alteration stress, which are factors that leads to the rice grain yield reduction. 相似文献