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In-silico study of E169G and F242K double mutations in leucine-rich repeats(LRR)polygalacturonase inhibiting protein(PGIP)of Gossypium barbadense and associated defense mechanism against plant pathogens
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作者 MURMU Sneha RASHMI Mayank +11 位作者 NAGRALE Dipak T. KOUR Tejasman SINGH Mahender Kumar CHAURASIA Anurag BEHERA Santosh Kumar SHANKAR Raja RANJAN Rajiv JHA Girish Kumar GAWANDE Shailesh P. HIREMANI Neelakanth S. PRASAD Y.G. KUMAR Sunil 《Journal of Cotton Research》 2025年第1期21-39,共19页
Background Polygalacturonase inhibiting proteins(PGIPs)play a pivotal role in plant defense against plant patho-gens by inhibiting polygalacturonase(PG),an enzyme produced by pathogens to degrade plant cell wall pecti... Background Polygalacturonase inhibiting proteins(PGIPs)play a pivotal role in plant defense against plant patho-gens by inhibiting polygalacturonase(PG),an enzyme produced by pathogens to degrade plant cell wall pectin.PGIPs,also known as leucine-rich repeat pathogenesis-related(PR)proteins,activate the host’s defense response upon interaction with PG,thereby reinforcing the host defense against plant pathogens attacks.In Egyptian or extra-long staple cotton(Gossypium barbadense),the interaction between PGIP and PG is one of the crucial steps in the defense mechanism against major pathogens such as Xanthomonas citri pv.malvacearum and Alternaria mac-rospora,which are responsible for bacterial leaf blight and leaf spot diseases,respectively.Results To unravel the molecular mechanisms underlying these PR proteins,we conducted a comprehensive study involving molecular modeling,protein-protein docking,site-specific double mutation(E169G and F242K),and molec-ular dynamics simulations.Both wild-type and mutated cotton PGIPs were examined in the interaction with the PG enzyme of a bacterial and fungal pathogen.Our findings revealed that changes in conformations of double-mutated residues in the active site of PGIP lead to the inhibition of PG binding.The molecular dynamics simulation studies provide insights into the dynamic behaviour and stability of the PGIP-PG complexes,shedding light on the intricate details of the inhibitory and exhibitory mechanism against the major fungal and bacterial pathogens of G.barbadense,respectively.Conclusions The findings of this study not only enhance our understanding of the molecular interactions between PGs of Xanthomonas citri pv.malvacearum and Alternaria macrospora and PGIP of G.barbadense but also pre-sent a potential strategy for developing the disease-resistant cotton varieties.By variations in the binding affinities of PGs through specific mutations in PGIP,this research offers promising avenues for the development of enhanced resistance to cotton plants against bacterial leaf blight and leaf spot diseases. 展开更多
关键词 Polygalacturonase inhibiting proteins POLYGALACTURONASE Plant-pathogen interaction Protein-protein interaction DOCKING Molecular dynamics simulation
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Retraction:MicroRNA-221-3p Plays an Oncogenic Role in Gastric Carcinoma by Inhibiting PTEN Expression
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作者 Oncology Research Editorial Office 《Oncology Research》 2025年第9期2598-2598,共1页
The published article titled“MicroRNA-221-3p Plays an Oncogenic Role in Gastric Carcinoma by Inhibiting PTEN Expression”has been retracted from Oncology Research,Vol.25,No.4,2017,pp.523–536.DOI:10.3727/096504016X14... The published article titled“MicroRNA-221-3p Plays an Oncogenic Role in Gastric Carcinoma by Inhibiting PTEN Expression”has been retracted from Oncology Research,Vol.25,No.4,2017,pp.523–536.DOI:10.3727/096504016X14756282819385 URL:https://www.techscience.com/or/v25n4/56833 Following the publication,concerns have been raised about a number of figures in this article.An unexpected area of similarity was identified in terms of the cellular data,where the results from differently performed experiments were intended to have been shown,although the areas immediately surrounding this area featured comparatively different distributions of cells.In addition,the western blots in this article were presented with atypical,unusually shaped and possibly anomalous protein bands in many cases. 展开更多
关键词 cellular datawhere microrna p PTEN western blots inhibiting pten expression gastric carcinoma cellular data RETRACTION
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Retraction:MicroRNA-92a Promotes Cell Proliferation in Cervical Cancer via Inhibiting p21 Expression and Promoting Cell Cycle Progression
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《Oncology Research》 2025年第12期4156-4156,共1页
The published article titled“MicroRNA-92a Promotes Cell Proliferation in Cervical Cancer via Inhibiting p21 Expression and Promoting Cell Cycle Progression”has been retracted from Oncology Research,Vol.25,No.1,2017,... The published article titled“MicroRNA-92a Promotes Cell Proliferation in Cervical Cancer via Inhibiting p21 Expression and Promoting Cell Cycle Progression”has been retracted from Oncology Research,Vol.25,No.1,2017,pp.137–145. 展开更多
关键词 cell proliferation microrna cervical cancer inhibiting p expression cell cycle progression P
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Inhibiting the P2–O2 phase transition of P2-Na_(0.67)Ni_(0.33)Mn_(0.67)O_(2)via high-valence tungsten doping for sodium-ion batteries
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作者 Shao-Yang Wu Fan Wu +6 位作者 Xin Ye Ling Sheng Hao-Dong Zhang Kang Liang Jian-Bin Li Yu-Rong Ren Peng Wei 《Rare Metals》 2025年第6期3806-3816,共11页
P2-type layered oxide cathode materials have attracted extensive attention due to their simple preparation,high specific capacity,adjustable voltage range,and high packing density.However,the harmful phase transitions... P2-type layered oxide cathode materials have attracted extensive attention due to their simple preparation,high specific capacity,adjustable voltage range,and high packing density.However,the harmful phase transitions that occur at high voltage severely limit their practical application.Herein,a novel high-valence tungsten doped P2-Na_(0.67)Ni_(0.33)Mn_(0.67)O_(2)cathode material was prepared using the sol–gel method.Through diffusion kinetics analysis and in situ X-ray diffraction(in situ XRD),it has been proven that W^(6+)not only enhances the Na^(+)diffusion coefficient but also reduces the P2–O2 phase transition.The optimized NNMO-W1%delivers a high discharge specific capacity of 163 mAh·g^(-1)at 0.1C,and the capacity retention rate is as high as 77.6%after 1000 cycles at 10C.This is mainly due to that W^(6+)enters the lattice,optimizing the arrangement of primary particles.This work sheds light on the design and construction of high-performance layered oxides cathode materials. 展开更多
关键词 Sodium-ion battery Layered-oxide cathodes High-valence doping Phase transition inhibition
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Thymosinα1 alleviates pulpitis by inhibiting ferroptosis of dental pulp cells
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作者 Jie Wu Qimei Gong +5 位作者 Wenxuan Liu Aijia Chen Zekai Liao Yihua Huang Wenkai Jiang Zhongchun Tong 《International Journal of Oral Science》 2025年第6期824-834,共11页
Tooth pulpitis is a prevalent oral disorder.Understanding the underlying mechanisms of pulpitis and developing effective treatment strategies hold great significance.Ferroptosis has recently emerged as a new form of c... Tooth pulpitis is a prevalent oral disorder.Understanding the underlying mechanisms of pulpitis and developing effective treatment strategies hold great significance.Ferroptosis has recently emerged as a new form of cell death,but the role of ferroptosis in pulpitis remains largely unknown.In our study,single-cell RNA sequencing(sc RNA-seq)was used to identify cellular heterogeneity between 3 pulpitis tissue and 3 healthy pulp tissue,and explored ferroptosis occurrence in pulpitis tissue and inflamed dental pulp cells(DPCs).In scRNA-seq,40231 cells(Pulpitis:17814;Healthy pulp:22417)were captured,and visualized into 12 distinct cell clusters.Differential y expressed ferroptosis-related genes(DE-FRGs)were almost presented in each cluster in pulpitis vs healthy pulp.ROS and Fe^(2+)levels significantly rose,and immunohistochemistry showed low expression of GPX4 and high expression of PTGS2 in pulpitis.In LPSstimulated DPCs,thymosinα1 increased the expression of GPX4 and FTL,and decreased expression of TNF-α,IL-1β,IL-6,and Fe^(2+)levels.In rat pulpitis models,both prothymosinα(PTMA,precursor of thymosinα1)gelatin sponge placed at the hole of pulp(LPS-P(gs))and PTMA injection in pulp(LPS-P(i))significantly reduced infiltration of inflammatory cells and expression of PTGS2,and increased the expression of GPX4.In RNA sequencing,the expression of DE-FRGs were reversed when thymosinα1 were added in LPS-stimulated DPCs.Collectively,single-cell atlas reveals cellular heterogeneity between pulpitis and healthy pulp,and ferroptosis occurrence in pulpitis.Thymosinα1 may reduce ferroptosis in DPCs to alleviate pulpitis and thus potentially has the ability to treat pulpitis. 展开更多
关键词 THYMOSIN alleviates pulpitis by inhibiting ferroptosis of dental pulp cells
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热风干燥对皂角刺干燥特性及其生物活性组分的影响
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作者 刘勇 张彩虹 +3 位作者 邓叶俊 王翔 谢普军 黄立新 《生物质化学工程》 2026年第1期1-9,共9页
以皂角刺为原料,采用热风干燥对其进行处理,选择皂角刺的含水率、水分比、干燥速率、有效水分扩散系数(D_(eff))及干燥活化能(Ea)为评价指标,探究热风干燥温度(30~70℃)对皂角刺干燥特性、干燥动力学、生物组成及活性影响。实验结果显示... 以皂角刺为原料,采用热风干燥对其进行处理,选择皂角刺的含水率、水分比、干燥速率、有效水分扩散系数(D_(eff))及干燥活化能(Ea)为评价指标,探究热风干燥温度(30~70℃)对皂角刺干燥特性、干燥动力学、生物组成及活性影响。实验结果显示:干燥温度对皂角刺中总皂苷、总多酚、总黄酮的含量及α-葡萄糖苷酶抑制活性均有影响。随温度升高,皂角刺干燥时间缩短、水分比降低、干燥速率加快,D_(eff)为2.34×10^(-10)~4.00×10^(-10)m^(2)/s,Ea为11.93 kJ/mol。随温度升高,皂角刺中总皂苷、总多酚、总黄酮与α-葡萄糖苷酶抑制活性均呈先增加后下降趋势,在60℃下皂角刺干燥速率较快,总皂苷(35.06±4.61 mg/g)、总多酚(92.44±1.12 mg/g)、总黄酮(48.38±2.21 mg/g)、α-葡萄糖苷酶抑制活性(59.36%±5.0%)达到最高。用HPLC测定皂角刺提取物中表儿茶素、花旗松素、芦丁、槲皮苷、漆黄素、芹菜素等多酚化合物的变化,结果显示:60℃下皂角刺中这6种常见多酚化合物的含量也显著高于其他温度下的含量。对皂角刺干燥过程的动力学模型拟合结果显示:7种干燥模型中,Modified Henderson and Pabis模型的R^(2)为0.996,拟合效果最佳。 展开更多
关键词 皂角刺 干燥特性 干燥动力学 生物组成 α-葡萄糖苷酶抑制
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Corrigendum
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《Neural Regeneration Research》 2026年第4期1276-1276,共1页
In the article titled“Inhibiting SHP2 reduces glycolysis,promotes microglial M1 polarization,and alleviates secondary inflammation following spinal cord injury in a mouse model,”published in Neural Regeneration Rese... In the article titled“Inhibiting SHP2 reduces glycolysis,promotes microglial M1 polarization,and alleviates secondary inflammation following spinal cord injury in a mouse model,”published in Neural Regeneration Research(Ding et al.,2025),the title was incorrectly presented due to an error during the language polishing process. 展开更多
关键词 language polishing process spinal cord injury reduces neural regeneration research ding inhibiting mouse model published microglial m polarizationand SHP
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Secretase inhibition in Alzheimer's disease therapeutics reveals functional roles of amyloid-beta42
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作者 Timothy Daly Bruno P.Imbimbo 《Neural Regeneration Research》 2026年第5期2003-2004,共2页
In the words of the late Sir Colin Blakemore,neurologists have historically sought to infer brain functions in a manner akin to to king a hammer to a computeranalyzing localized anatomical lesions caused by trauma,tum... In the words of the late Sir Colin Blakemore,neurologists have historically sought to infer brain functions in a manner akin to to king a hammer to a computeranalyzing localized anatomical lesions caused by trauma,tumors,or strokes,noting deficits,and inferring what functions certain brain regions may be responsible for.This approach exemplifies a deletion heuristic,where the absence of a specific function reveals insights about the underlying structures or mechanisms responsible for it.By observing what is lost when a particular brain region is damaged,throughout the history of the field,neurologists have pieced together the intricate relationship between anatomy and function. 展开更多
关键词 infer brain functions secretase inhibition Alzheimers disease therapeutics king hammer deletion heuristic amyloid beta deletion heuristicwhere observing what l
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Empowering the NSC-34 cell line as a motor neuron model: Cytosine arabinoside's action
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作者 Giuseppe Vitale Susanna Amadio +1 位作者 Francesco Liguori Cinzia Volonté 《Neural Regeneration Research》 2026年第1期357-364,共8页
The NSC-34 cell line is a widely recognized motor neuron model and various neuronal differentiation protocols have been exploited. Under previously reported experimental conditions, only part of the cells resemble dif... The NSC-34 cell line is a widely recognized motor neuron model and various neuronal differentiation protocols have been exploited. Under previously reported experimental conditions, only part of the cells resemble differentiated neurons;however, they do not exhibit extensive and time-prolonged neuritogenesis, and maintain their duplication capacity in culture. The aim of the present work was to facilitate long-term and more homogeneous neuronal differentiation in motor neuron–like NSC-34 cells. We found that the antimitotic drug cytosine arabinoside promoted robust and persistent neuronal differentiation in the entire cell population. Long and interconnecting neuronal processes with abundant growth cones were homogeneously induced and were durable for up to at least 6 weeks in culture. Moreover, cytosine arabinoside was permissive, dispensable, and mostly irreversible in priming NSC-34 cells for neurite initiation and regeneration after mechanical dislodgement. Finally, the expression of the cell proliferation antigen Ki67 was inhibited by cytosine arabinoside, whereas the expression levels of neuronal growth associated protein 43, vimentin, and motor neuron–specific p75, Islet2, homeobox 9 markers were upregulated, as confirmed by western blot and/or confocal immunofluorescence analysis. Overall, these findings support the use of NSC-34 cells as a motor neuron model for properly investigating neurodegenerative mechanisms and prospectively identifying neuroprotective strategies. 展开更多
关键词 cytosine arabinoside Islet2 Hb9 Ki67 mitosis inhibition neurite initiation neurite regeneration neuronal differentiation protocol NSC-34 P75
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基于环氧乙烷改性咪唑啉复合缓蚀剂的研制及应用
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作者 吴豹 铁磊磊 +2 位作者 曾浩见 汪洋 刘陆芃 《精细石油化工》 2026年第1期15-18,共4页
以油酸、羟乙基二胺、环氧乙烷合成的羟乙基二胺油酸咪唑啉单体(YQH-12)为主剂,优选出分散剂APE和防乳化剂XP-3,在5%NaCl溶液中水溶性良好,不分层,并且能够有效降低YQH-12的乳化倾向。复配8%BGA+10%BD-X后形成了一种复合缓蚀剂,该缓蚀... 以油酸、羟乙基二胺、环氧乙烷合成的羟乙基二胺油酸咪唑啉单体(YQH-12)为主剂,优选出分散剂APE和防乳化剂XP-3,在5%NaCl溶液中水溶性良好,不分层,并且能够有效降低YQH-12的乳化倾向。复配8%BGA+10%BD-X后形成了一种复合缓蚀剂,该缓蚀剂能够有效抑制剂CO_(2)和H_(2)S腐蚀。通过动态腐蚀评价实验模拟现场工况条件,在50µg/g条件下,X65钢材腐蚀速率降低至0.046 mm/a,缓蚀率达到94.72%。 展开更多
关键词 改性咪唑啉 环氧乙烷 腐蚀评价 防乳化 水溶性 缓蚀率
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超高矿化度卤水基修井液研究与性能评价
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作者 贾文峰 宋佳俊 +3 位作者 李进 任日坤 陈雪 鲜成钢 《精细石油化工》 2026年第1期60-63,共4页
以超高矿化度玛湖地表盐水为溶剂,优选了增黏剂、降滤失剂、缓蚀剂等助剂,构建了一套适合玛湖1井区的超高矿化度玛湖盐水基修井液体系。该修井液配方为:240 mL玛湖盐水+60 mL清水+4%膨润土+0.5%PAC-HV+0.3%PAC-LV+1%重质超细碳酸钙(3 00... 以超高矿化度玛湖地表盐水为溶剂,优选了增黏剂、降滤失剂、缓蚀剂等助剂,构建了一套适合玛湖1井区的超高矿化度玛湖盐水基修井液体系。该修井液配方为:240 mL玛湖盐水+60 mL清水+4%膨润土+0.5%PAC-HV+0.3%PAC-LV+1%重质超细碳酸钙(3 000目)+0.6%ODD+0.2%NTA+重晶石。室内实验结果表明:该体系流变性能良好,FL_(API)滤失量为4.4 mL,防膨率达95.42%,腐蚀速率小于0.020 00 mm/a,且经100℃高温老化16 h后其流变性能、降滤失性能、防膨性能及缓蚀性能基本不变。 展开更多
关键词 流变性 滤失性 修井液 防膨性 卤水基 超高矿化度
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肉桂酸对α-淀粉酶的抑制作用及机理研究
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作者 吕俊丽 云月英 +1 位作者 任艳 何璇 《食品与发酵工业》 北大核心 2026年第1期237-243,共7页
为了探究肉桂酸对α-淀粉酶的抑制特性,该研究采用光谱法与分子对接法相结合,研究了肉桂酸对α-淀粉酶的抑制效果及其作用机制。结果显示,肉桂酸在0.04~0.20 mmol/L的浓度内,对α-淀粉酶的抑制率最高为78.05%。紫外光谱显示,α-淀粉酶... 为了探究肉桂酸对α-淀粉酶的抑制特性,该研究采用光谱法与分子对接法相结合,研究了肉桂酸对α-淀粉酶的抑制效果及其作用机制。结果显示,肉桂酸在0.04~0.20 mmol/L的浓度内,对α-淀粉酶的抑制率最高为78.05%。紫外光谱显示,α-淀粉酶特征峰的位置并未随着肉桂酸浓度的增加发生明显偏移,但同一波长下α-淀粉酶对紫外光的吸收增强,具有浓度依赖性。荧光光谱结果显示,肉桂酸与α-淀粉酶之间有1个结合位点,猝灭机制为静态猝灭,肉桂酸与α-淀粉酶相互作用的熵变(ΔH)为134.785 kJ/mol和焓变(ΔS)为504.552 J/(mol·K),均大于0,二者之间主要作用力为疏水作用。分子对接结果显示,肉桂酸与α-淀粉酶结合的最低结合能为-23.263 kJ/mol,除疏水相互作用外,范德华力、氢键等作用力也是肉桂酸与α-淀粉酶分子维持稳定的重要因素。上述结果表明,肉桂酸在抑制α-淀粉酶活性方面具有一定的潜力,为2型糖尿病患者功能食品的开发奠定理论基础。 展开更多
关键词 肉桂酸 Α-淀粉酶 抑制 光谱 分子对接
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青稞麸皮β-葡聚糖提取工艺优化及体外降脂活性
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作者 凡福宝 白增芳 +2 位作者 云生敏 叶英 王煜伟 《食品研究与开发》 2026年第1期93-100,共8页
以青稞麸皮为原料,通过水提法提取β-葡聚糖,以β-葡聚糖提取率为评价指标,通过单因素和响应面试验优化青稞麸皮β-葡聚糖的提取工艺;以纯化后β-葡聚糖纯度和提取率为主要评价指标,优化青稞麸皮β-葡聚糖的纯化工艺。结果表明,青稞麸皮... 以青稞麸皮为原料,通过水提法提取β-葡聚糖,以β-葡聚糖提取率为评价指标,通过单因素和响应面试验优化青稞麸皮β-葡聚糖的提取工艺;以纯化后β-葡聚糖纯度和提取率为主要评价指标,优化青稞麸皮β-葡聚糖的纯化工艺。结果表明,青稞麸皮β-葡聚糖最优提取工艺为提取液pH8、料液比1∶20(g/mL)、提取温度66℃、提取时间2.25 h。最优条件下β-葡聚糖提取率为(5.027±0.064)%,与预测值5.014%相符合。青稞麸皮β-葡聚糖最优纯化条件为在提取液中加入α-淀粉酶(50 U/L),60℃水浴1 h,后加入糖化酶(250 U/L),60℃孵浴1 h,离心(3000 r/min、10 min)后取上清液浓缩,醇沉离心,沉淀热水复溶,冻融后离心,冻干沉淀。纯化得到的青稞麸皮β-葡聚糖纯度为(77.50±0.60)%。对所得β-葡聚糖进行胰脂肪酶抑制能力测定,发现当青稞麸皮β-葡聚糖浓度为10.0 mg/mL时,对胰脂肪酶抑制率可达76.70%。综上,优化后的青稞麸皮β-葡聚糖水提工艺简单、稳定,得到的β-葡聚糖产品有良好的体外降脂活性。 展开更多
关键词 青稞麸皮 Β-葡聚糖 水提法 胰脂肪酶抑制率 体外降脂
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ZBP1(DAI/DLM-1) promotes osteogenic differentiation while inhibiting adipogenic differentiation in mesenchymal stem cells through a positive feedback loop of Wnt/β-catenin signaling 被引量:14
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作者 Xuefeng Zhao Liang Xie +5 位作者 Zhiyong Wang Jiongke Wang Hao Xu Xianglong Han Ding Bai Peng Deng 《Bone Research》 SCIE CAS CSCD 2020年第2期219-228,共10页
The lineage specification of mesenchymal stem/stromal cells(MSCs) is tightly regulated by a wide range of factors. Recently, the versatile functions of ZBP1(also known as DAI or DLM-1) have been reported in the blood ... The lineage specification of mesenchymal stem/stromal cells(MSCs) is tightly regulated by a wide range of factors. Recently, the versatile functions of ZBP1(also known as DAI or DLM-1) have been reported in the blood circulation and immune systems.However, the biological function of ZBP1 during the lineage specification of MSCs is still unknown. In the present study, we found that ZBP1 was upregulated during osteogenesis but downregulated during adipogenesis in mouse bone marrow-derived MSCs(m BMSCs). ZBP1 was highly expressed in osteoblasts but expressed at a relatively low level in marrow adipocytes. Knockdown of ZBP1 inhibited alkaline phosphataseactivity, extracellular matrix mineralization, and osteogenesis-related gene expression in vitro and reduced ectopic bone formation in vivo. Knockdown of ZBP1 also promoted adipogenesis in MSCs in vitro. Conversely, the overexpression of ZBP1 increased the osteogenesis but suppressed the adipogenesis of MSCs. When the expression of ZBP1 was rescued, the osteogenic capacity of ZBP1-depleted m BMSCs was restored at both the molecular and phenotypic levels.Furthermore, we demonstrated that ZBP1, a newly identified target of Wnt/β-catenin signaling, was required for β-catenin translocation into nuclei. Collectively, our results indicate that ZBP1 is a novel regulator of bone and fat transdifferentiation via Wnt/β-catenin signaling. 展开更多
关键词 inhibited inhibiting VERSATILE
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马尾藻类菌孢素氨基酸的提取工艺优化及其对酪氨酸酶活性的抑制机理
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作者 李田乐 蒋秀婧 +5 位作者 潘明轩 韦欣 焦学 王欣冉 胡亚东 孙颖颖 《食品工业科技》 北大核心 2026年第3期263-274,I0005,I0006,共14页
为探究马尾藻类菌孢素氨基酸(Mycosporine-like amino acids,MAAs)提取物对酪氨酸酶活性的影响,本研究首先采用单因素和响应面优化试验,分析甲醇浓度、液料比、提取温度和提取时间等因素,以马尾藻MAAs的得率及其对酪氨酸酶活性的抑制率... 为探究马尾藻类菌孢素氨基酸(Mycosporine-like amino acids,MAAs)提取物对酪氨酸酶活性的影响,本研究首先采用单因素和响应面优化试验,分析甲醇浓度、液料比、提取温度和提取时间等因素,以马尾藻MAAs的得率及其对酪氨酸酶活性的抑制率为指标,建立马尾藻MAAs的适宜提取工艺。在此基础上,采用薄层层析、紫外光谱、高效液相色谱和分光光度法,对工艺优化后的MAAs提取物进行定性定量、体外抗氧化和抗酪氨酸酶活性分析。进一步,通过酶反应动力学分析、铜离子螯合实验和酪氨酸酶荧光猝灭实验,确定马尾藻MAAs对酪氨酸酶活性的抑制作用机理。结果表明,马尾藻MAAs的适宜提取参数为温度41℃、液料比26 mL/g、时间2.6 h和甲醇浓度31%,MAAs得率为89.87±0.73 mg/g,其对酪氨酸酶活性的抑制率IC_(50)为2.23±0.32 mg/mL。马尾藻MAAs具备清除DPPH(IC_(50)为0.17±0.06 mg/mL)和ABTS^(+)(IC_(50)为1.03±0.21 mg/mL)自由基的能力,以及螯合铜离子(半螯合浓度为0.70±0.21 mg/mL)的能力。马尾藻MAAs对酪氨酸酶活性的抑制作用为可逆、混合型抑制。马尾藻MAAs具有酪氨酸酶抑制活性,可有效阻断黑色素合成途径,在防止生鲜果蔬和饮料褐变以及预防虾类黑变病等方面具有潜在应用前景。 展开更多
关键词 马尾藻 类菌孢素氨基酸 提取工艺 酪氨酸酶 抑制机理
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Inhibiting Effect of Ciprofloxacin,Norfloxacin and Ofloxacin on Corrosion of Mild Steel in Hydrochloric Acid 被引量:8
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作者 庞雪辉 冉祥滨 +2 位作者 匡飞 解建东 侯保荣 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第2期337-345,共9页
The inhibiting effect of ciprofloxacin,norfloxacin and ofloxacin on the corrosion of mild steel in 1 mol·L-1 HCl and the mechanism were studied at different temperatures using mass loss measurement,electrochemica... The inhibiting effect of ciprofloxacin,norfloxacin and ofloxacin on the corrosion of mild steel in 1 mol·L-1 HCl and the mechanism were studied at different temperatures using mass loss measurement,electrochemical method,and X-ray photoelectron spectroscopy(XPS) .Effective inhibition was shown by mass loss,potentiodynamic polarization and impedance spectroscopy measurement.The corrosion rate of the metal in the mass loss measurement,and the corrosion reaction on cathode and anode in the electrochemical measurement were accelerated when temperature was increased.XPS results showed that the inhibitors adsorbed effectively on the metal surface. 展开更多
关键词 CORROSION INHIBITION electrochemical impedance spectroscopy potentiodynamic polarization X-ray photoelectron spectroscopy
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Transcriptomic and metabolomic analyses reveal that melatonin promotes melon root development under copper stress by inhibiting jasmonic acid biosynthesis 被引量:9
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作者 Zhicheng Hu Qiushi Fu +2 位作者 Jing Zheng Aiai Zhang Huaisong Wang 《Horticulture Research》 SCIE 2020年第1期1636-1650,共15页
Melatonin has been shown to alleviate the effects of abiotic stress and to regulate plant development.Copper,a common heavy metal and soil pollutant,can suppress plant growth and development.In this work,we explored t... Melatonin has been shown to alleviate the effects of abiotic stress and to regulate plant development.Copper,a common heavy metal and soil pollutant,can suppress plant growth and development.In this work,we explored the protective effects of exogenous melatonin on lateral root formation in response to copper stress using melon seeds subjected to three germination treatments:CK1(control),CK2(300μmol/L CuSO4),and MT3(300μmol/L melatonin+300μmol/L CuSO4).Melatonin pretreatment increased the antioxidant enzyme activities and root vigor,and decreased the proline and malondialdehyde(MDA)contents in the roots of copper-stressed melon seedlings.We then used transcriptomic and metabolomic analyses to explore the mechanisms by which exogenous melatonin protects against copper stress.There were 70 significant differentially expressed genes(DEGs)(28 upregulated,42 downregulated)and 318 significantly differentially expressed metabolites(DEMs)(168 upregulated,150 downregulated)between the MT3 and CK2 treatments.Melatonin pretreatment altered the expression of genes related to redox and cell wall formation processes.In addition,we found that members of the AP2/ERF,BBR/BPC,GRAS,and HD-ZIP transcription factor families may have vital roles in lateral root development.Melatonin also increased the level of Glutathione(GSH),which chelates excess Cu^(2+).The combined transcriptomic and metabolomic analysis revealed DEGs and DEMs involved in jasmonic acid(JA)biosynthesis,including four lipoxygenase-related genes and two metabolites(linoleic acid and lecithin)related to melatonin’s alleviation effect on copper toxicity.This research elucidated the molecular mechanisms of melatonin’s protective effects in copper-stressed melon. 展开更多
关键词 protective inhibiting copper
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Molecular mechanisms of inhibiting glucosyltransferases for biofilm formation in Streptococcus mutans 被引量:6
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作者 Qiong Zhang Qizhao Ma +2 位作者 Yan Wang Hui Wu Jing Zou 《International Journal of Oral Science》 SCIE CAS CSCD 2021年第3期243-250,共8页
Glucosyltransferases(Gtfs)play critical roles in the etiology and pathogenesis of Streptococcus mutans(S.mutans)-mediated dental caries including early childhood caries.Gtfs enhance the biofilm formation and promotes ... Glucosyltransferases(Gtfs)play critical roles in the etiology and pathogenesis of Streptococcus mutans(S.mutans)-mediated dental caries including early childhood caries.Gtfs enhance the biofilm formation and promotes colonization of cariogenic bacteria by generating biofilm extracellular polysaccharides(EPSs),the key virulence property in the cariogenic process.Therefore,Gtfs have become an appealing target for effective therapeutic interventions that inhibit cariogenic biofilms.Importantly,targeting Gtfs selectively impairs the S.mutans virulence without affecting S.mutans existence or the existence of other species in the oral cavity.Over the past decade,numerous Gtfs inhibitory molecules have been identified,mainly including natural and synthetic compounds and their derivatives,antibodies,and metal ions.These therapeutic agents exert their inhibitory role in inhibiting the expression gtf genes and the activities and secretion of Gtfs enzymes with a wide range of sensitivity and effectiveness.Understanding molecular mechanisms of inhibiting Gtfs will contribute to instructing drug combination strategies,which is more effective for inhibiting Gtfs than one drug or class of drugs.This review highlights our current understanding of Gtfs activities and their potential utility,and discusses challenges and opportunities for future exploration of Gtfs as a therapeutic target. 展开更多
关键词 inhibiting MECHANISMS instru
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Role of ammonium sulfate in sulfurization flotation of azurite:Inhibiting the formation of copper sulfide colloid and its mechanism 被引量:5
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作者 Jinpeng Cai Chao Su +7 位作者 Yinyu Ma Xingcai Yu Rong Peng Jiangli Li Xiaolin Zhang Jianjun Fang Peilun Shen Dianwen Liu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第3期575-584,共10页
In this study,the role of(NH_(4))_(2)SO_(4)during the sulfurization of azurite and its response to flotation were investigated.The flotation results showed that adding(NH_(4))_(2)SO_(4)prior to sulfurization decreased... In this study,the role of(NH_(4))_(2)SO_(4)during the sulfurization of azurite and its response to flotation were investigated.The flotation results showed that adding(NH_(4))_(2)SO_(4)prior to sulfurization decreased the formation of colloid in flotation pulp,and the floatability of the suppressed azurite caused by excess sodium sulfide was restored.After adding(NH_(4))_(2)SO_(4)prior to sulfurization,the formation of Cu(NH_(3))_(n) ^(2+)intermediate products changed the path of the sulfurization reaction,which slowed the direct impact of HSon the azurite surface.The nucleation rate was reduced,and the growth of copper sulfide crystal was improved.Covellite(syn,CuS)with larger crystal grains was formed on the azurite surface,thereby enhancing the mechanical stability of copper sulfide products onto the mineral surface.Therefore,the generated copper sulfide colloid significantly reduced,ultimately promoting the effective adsorption of xanthate on the azurite surface. 展开更多
关键词 AZURITE Sulfurization flotation Ammonium sulfate COLLOID Inhibition Crystal growth
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miR-140-3p enhanced the osteo/odontogenic differentiation of DPSCs via inhibiting KMT5B under hypoxia condition 被引量:5
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作者 Han Zheng Ning Wang +3 位作者 Le Li Lihua Ge Haichao Jia Zhipeng Fan 《International Journal of Oral Science》 SCIE CAS CSCD 2021年第4期398-407,共10页
Human dental pulp stem cells(DPSCs)have emerged as an important source of stem cells in the tissue engineering,and hypoxia will change various innate characteristics of DPSCs and then affect dental tissue regeneration... Human dental pulp stem cells(DPSCs)have emerged as an important source of stem cells in the tissue engineering,and hypoxia will change various innate characteristics of DPSCs and then affect dental tissue regeneration.Nevertheless,little is known about the complicated molecular mechanisms.In this study,we aimed to investigate the influence and mechanism of miR-140-3p on DPSCs under hypoxia condition.Hypoxia was induced in DPSCs by Cobalt chloride(CoCl_(2))treatment.The osteo/dentinogenic differentiation capacity of DPSCs was assessed by alkaline phosphatase(ALP)activity,Alizarin Red S staining and main osteo/dentinogenic markers.A luciferase reporter gene assay was performed to verify the downstream target gene of miR-140-3p.This research exhibited that miR-140-3p promoted osteo/dentinogenic differentiation of DPSCs under normoxia environment.Furthermore,miR-140-3p rescued the CoCl_(2)-induced decreased osteo/odontogenic differentiation potentials in DPSCs.Besides,we investigated that miR-140-3p directly targeted lysine methyltransferase 5B(KMT5B).Surprisingly,we found inhibition of KMT5B obviously enhanced osteo/dentinogenic differentiation of DPSCs both under normoxia and hypoxia conditions.In conclusion,our study revealed the role and mechanism of miR-140-3p for regulating osteo/dentinogenic differentiation of DPSCs under hypoxia,and discovered that miR-140-3p and KMT5B might be important targets for DPSC-mediated tooth or bone tissue regeneration. 展开更多
关键词 DPSCs MIR inhibiting
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