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枯草芽孢杆菌漆酶的理性设计及在霉菌毒素降解的应用
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作者 乐琛 王晓 +3 位作者 谢珂 郑艳丽 杨江科 雷磊 《食品与发酵工业》 CAS CSCD 北大核心 2024年第17期1-10,共10页
为解决目前制约食品等领域发展的霉菌毒素污染问题,选取了枯草芽孢杆菌来源的BsCotA漆酶并且通过理性设计提高酶活力、稳定性,从而实现对霉菌毒素降解效率的提高。利用理性设计改造BsCotA漆酶,获得了4个突变体漆酶,包括3个点突变体CotA^... 为解决目前制约食品等领域发展的霉菌毒素污染问题,选取了枯草芽孢杆菌来源的BsCotA漆酶并且通过理性设计提高酶活力、稳定性,从而实现对霉菌毒素降解效率的提高。利用理性设计改造BsCotA漆酶,获得了4个突变体漆酶,包括3个点突变体CotA^(A344K)、CotA^(A317T)、CotA^(T36Y),和突变整合体CotAgold,使用毕赤酵母进行异源表达,测定其酶学性质,并检测其对霉菌毒素的降解效率。基于蛋白质结构进行设计的3个单点突变,均从不同程度上提高了漆酶的稳定性。而将3个突变位点同时整合到1个漆酶突变体上时,3个突变位点间未发生显著拮抗作用,使得突变整合体CotAgold展示出最好的稳定性以及催化能力;CotAgold比酶活力为99.4 U/mg,相比BsCotA的比酶活力提高了10倍,对于ABTS的k_(cat)/K_(M)达到了7.12×10^(5)L/(mol·s),相比BsCotA提高了1.9倍;突变体CotAgold的最适反应pH值为4,最适反应温度均为70℃,与野生型BsCotA催化条件保持一致;CotAgold在pH 2~12,孵育30 min,剩余酶活力均在70%以上,相比野生型BsCotA在酸性条件下的稳定性有明显提高;CotAgold在40~90℃,孵育30 min,残留酶活力均在90%以上,相比野生型BsCotA在高温条件下的稳定性有明显提高;并在ABTS阳离子自由基作为介体的条件下,漆酶CotAgold能完全降解黄曲霉毒素B1和玉米赤霉烯酮;相比之下,野生型漆酶BsCotA的降解率仅为5%。通过蛋白质的理性设计得到了漆酶突变体CotAgold,表现出显著提高的pH稳定性以及热稳定性,蛋白表达量也有一定的提高,在霉菌毒素降解等领域具有良好的应用前景。 展开更多
关键词 漆酶 理性设计 酶学性质 毒素降解 黄曲霉毒素B1 玉米赤霉烯酮
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透骨消痛胶囊调控Nav1.7减轻膝骨关节炎小鼠软骨细胞退变
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作者 付长龙 林艳铭 +4 位作者 兰书洁 陈悦 李超 陆诗雨 林晴 《南方医科大学学报》 CAS CSCD 北大核心 2024年第11期2074-2081,共8页
目的从Nav1.7调控软骨细胞外基质稳态角度,研究透骨消痛胶囊对减轻膝骨关节炎(KOA)软骨细胞退变的作用机制。方法选择40只2月龄C57BL/6小鼠,通过随机数字表法将其分为空白组(n=10)和造模组(n=30)。造模组小鼠通过Hulth法手术建立KOA模型... 目的从Nav1.7调控软骨细胞外基质稳态角度,研究透骨消痛胶囊对减轻膝骨关节炎(KOA)软骨细胞退变的作用机制。方法选择40只2月龄C57BL/6小鼠,通过随机数字表法将其分为空白组(n=10)和造模组(n=30)。造模组小鼠通过Hulth法手术建立KOA模型后,随机分为模型组(生理盐水灌胃)、透骨消痛胶囊组(368 mg/kg剂量灌胃)、阳性药物组(10 mg/kg双氯芬酸钠灌胃),10只/组;空白组为生理盐水灌胃,干预6次/周,共4周。干预后5%异氟醚麻醉处死,获得膝关节软骨组织。形态学染色观察软骨组织结构变化,实时荧光定量PCR检测Nav1.7 mRNA水平,Western blotting分析Nav1.7、MMP-3、ADAMTS-5、COX-2蛋白表达变化。荧光原位杂交检测软骨细胞中Nav1.7的表达量。此外,利用慢病毒载体敲减Nav1.7(sh-Nav1.7)转染软骨细胞,实时荧光定量PCR分析转染后sh-Nav1.7在软骨细胞中mRNA水平变化。Western blotting分析在sh-Nav1.7条件下,透骨消痛胶囊对KOA软骨细胞MMP-3、MMP-13、ADAMTS-4、ADAMTS-5、COX-2蛋白的调控。结果形态学结果显示,和模型组对比,透骨消痛胶囊组和阳性药物组软骨层结构更完整,关节结构破坏程度减轻。透骨消痛胶囊组和阳性药物组的Nav1.7蛋白与mRNA水平降低(P<0.05),MMP-3、ADAMTS-5、COX-2蛋白表达减少(P<0.05)。荧光原位杂交结果显示,透骨消痛胶囊能降低IL-1β诱导的Nav1.7的荧光强度。在Nav1.7敲减实验中,与IL-1β组相比,IL-1β+sh-Nav1.7组中Nav1.7水平下降(P<0.05);与IL-1β+TGXTC组相比,IL-1β+sh-Nav1.7+TGXTC组中Nav1.7水平下降(P<0.05)。Western blotting结果表明,IL-1β组软骨细胞中升高的MMP-3、MMP-13、ADAMTS-4、ADAMTS-5、COX-2蛋白被透骨消痛胶囊干预后显著抑制(P<0.05),但在Nav1.7敲低后,透骨消痛胶囊对这些蛋白的调控作用减弱(P<0.05)。结论透骨消痛胶囊通过调控Nav1.7减轻KOA软骨细胞外基质代谢紊乱,从而发挥减轻软骨细胞退变的作用。 展开更多
关键词 透骨消痛胶囊 Nav1.7 软骨退变 膝骨关节炎
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Amitriptyline inhibits NLRP3 inflammasome activation via the ASM/CE pathway in a cell model of NAFLD 被引量:1
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作者 QIN LIU CHUNYAN NIU +3 位作者 QIANG ZHANG SHIQIN SUN yue chen YONGQIANG SHI 《BIOCELL》 SCIE 2024年第5期759-769,共11页
Background:Nonalcoholic fatty liver disease(NAFLD)is a global health concern with the acid sphingomyelinase(ASM)/ceramide(CE)pathway and the NOD-like receptor family,pyrin domain-containing protein 3(NLRP3)inflammasom... Background:Nonalcoholic fatty liver disease(NAFLD)is a global health concern with the acid sphingomyelinase(ASM)/ceramide(CE)pathway and the NOD-like receptor family,pyrin domain-containing protein 3(NLRP3)inflammasome identified as pivotal players in lipid disorders and inflammation.This study explores the interaction mechanism between the ASM/CE pathway and NLRP3 in NAFLD cell models,aiming to understand the impact of amitriptyline(Ami),an ASM inhibitor,on lipid deposition and hepatocyte injury by regulating the ASM/CE-NLRP3 pathway.Methods:HepG2 and HL-7702 cells were exposed to free fatty acids(FFAs)to establish the NAFLD model.The cells were divided into 5 groups:control group,model group,Ami group,tumor necrosis factoralpha(TNF-α)group,and Ami+TNF-αgroup.Intracellular lipid droplets were visualized using Oil Red O staining,and Western blot analysis quantified ASM,NLRP3,and caspase 1 protein expression.Enzyme linked immunosorbent assay(ELISA)was measured CE and ASM levels,while qRT-PCR assessed mRNA expression.The apoptotic rate was evaluated by flow cytometry(FCM).Results:Following FFAs incubation,significant increases in ASM and CE levels were observed in HepG2 and HL-7702 cells,accompanied by elevated expression of NLRP3,and caspase 1,and IL-1β.TNF-αtreatment further amplified these indicators.Ami demonstrated a reduction in lipid deposition,suppressed ASM/CE pathway activation,downregulated NLRP3 and caspase 1 expression,and improved apoptosis.Additionally,MCC950,a selective inhibitor of the NLRP3,mitigated NLRP3,caspase 1,and IL-1βexpression,alleviating lipid deposition and apoptosis in the NAFLD cell model.Conclusion:The ASM/CE-NLRP3 pathway in NAFLD cells promotes hepatocyte steatosis,inflammation,and cell damage.Ami emerges as a promising therapeutic agent by inhibiting the ASM/CE-NLRP3 pathway,underscoring its potential as a key target for NAFLD treatment. 展开更多
关键词 Nonalcoholic fatty liver disease HEPATOCYTE AMITRIPTYLINE ASM/CE pathway NLRP3 Nonalcoholic steatohepatitis
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Tree mycorrhizal associations determine how biodiversity,large trees,and environmental factors drive aboveground carbon stock in temperate forests
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作者 yue chen Zikun Mao +2 位作者 Jonathan A.Myers Jinghua Yu Xugao Wang 《Forest Ecosystems》 SCIE CSCD 2024年第4期448-456,共9页
Biodiversity,large trees,and environmental conditions such as climate and soil have important effects on forest carbon stocks.However,recent studies in temperate forests suggest that the relative importance of these f... Biodiversity,large trees,and environmental conditions such as climate and soil have important effects on forest carbon stocks.However,recent studies in temperate forests suggest that the relative importance of these factors depends on tree mycorrhizal associations,whereby large-tree effects may be driven by ectomycorrhizal(EM)trees,diversity effects may be driven by arbuscular mycorrhizal(AM)trees,and environment effects may depend on differential climate and soil preferences of AM and EM trees.To test this hypothesis,we used forest-inventory data consisting of over 80,000 trees from 631 temperate-forest plots(30 m×30 m)across Northeast China to examine how biodiversity(species diversity and ecological uniqueness),large trees(top 1%of tree diameters),and environmental factors(climate and soil nutrients)differently regulate aboveground carbon stocks of AM trees,EM trees,and AM and EM trees combined(i.e.total aboveground carbon stock).We found that large trees had a positive effect on both AM and EM tree carbon stocks.However,biodiversity and environmental factors had opposite effects on AM vs.EM tree carbon stocks.Specifically,the two components of biodiversity had positive effects on AM tree carbon stocks,but negative effects on EM tree carbon stocks.Environmental heterogeneity(mean annual temperature and soil nutrients)also exhibited contrasting effects on AM and EM tree carbon stocks.Consequently,for the total carbon stock,the positive large-tree effect far surpasses the diversity and environment effect.This is mainly because when integrating AM and EM tree carbon stock into total carbon stock,the opposite diversity-effect(also environment-effect)on AM vs.EM tree carbon stock counteracts each other while the consistent positive large-tree effect on AM and EM tree carbon stock is amplified.In summary,this study emphasized a mycorrhizal viewpoint to better understand the determinants of overarching aboveground carbon profile across regional forests. 展开更多
关键词 BIODIVERSITY Ecological uniqueness Environment heterogeneity Large trees Mycorrhizal associations Tree carbon stock
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Composition,function,and timing:exploring the early‑life gut microbiota in piglets for probiotic interventions
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作者 Jianping Quan Cineng Xu +14 位作者 Donglin Ruan Yong Ye Yibin Qiu Jie Wu Shenping Zhou Menghao Luan Xiang Zhao yue chen Danyang Lin Ying Sun Jifei Yang Enqin Zheng Gengyuan Cai Zhenfang Wu Jie Yang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期659-678,共20页
Background The establishment of a robust gut microbiota in piglets during their early developmental stage holds the potential for long-term advantageous effects.However,the optimal timeframe for introducing probiotics... Background The establishment of a robust gut microbiota in piglets during their early developmental stage holds the potential for long-term advantageous effects.However,the optimal timeframe for introducing probiotics to achieve this outcome remains uncertain.Results In the context of this investigation,we conducted a longitudinal assessment of the fecal microbiota of 63 piglets at three distinct pre-weaning time points.Simultaneously,we gathered vaginal and fecal samples from 23 sows.Employing 16S rRNA gene and metagenomic sequencing methodologies,we conducted a comprehensive analysis of the fluctuation patterns in microbial composition,functional capacity,interaction networks,and colonization resistance within the gut microbiota of piglets.As the piglets progressed in age,discernible modifications in intestinal microbial diversity,composition,and function were observed.A source-tracking analysis unveiled the pivotal role of fecal and vaginal microbiota derived from sows in populating the gut microbiota of neonatal piglets.By D21,the microbial interaction network displayed a more concise and efficient configuration,accompanied by enhanced colonization resistance relative to the other two time points.Moreover,we identified three strains of Ruminococcus sp.at D10 as potential candidates for improving piglets’weight gain during the weaning phase.Conclusions The findings of this study propose that D10 represents the most opportune juncture for the introduction of external probiotic interventions during the early stages of piglet development.This investigation augments our comprehension of the microbiota dynamics in early-life of piglets and offers valuable insights for guiding forthcoming probiotic interventions. 展开更多
关键词 Colonization resistance Intestinal microbiota PIGLET WEANING Weight gain
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PHD17 acts as a target of miR1320 to negatively control cold tolerance via JA-activated signaling in rice
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作者 Yan Wang Yang Shen +6 位作者 Weifeng Dong Xiaoxi Cai Junkai Yang yue chen Bowei Jia Mingzhe Sun Xiaoli Sun 《The Crop Journal》 SCIE CSCD 2024年第5期1447-1458,共12页
Plant Homeo Domain(PHD)proteins are involved in diverse biological processes during plant growth.However,the regulation of PHD genes on rice cold stress response remains largely unknown.Here,we reported that PHD17 neg... Plant Homeo Domain(PHD)proteins are involved in diverse biological processes during plant growth.However,the regulation of PHD genes on rice cold stress response remains largely unknown.Here,we reported that PHD17 negatively regulated cold tolerance in rice seedlings as a cleavage target of miR1320.PHD17 expression was greatly induced by cold stress,and was down-regulated by miR1320 overexpression and up-regulated by miR1320 knockdown.Through 5'RACE and dual luciferase assays,we found that miR1320 targeted and cleaved the 3'UTR region of PHD17.PHD17 was a nuclearlocalized protein and acted as a transcriptional activator in yeast.PHD17 overexpression reduced cold tolerance of rice seedlings,while knockout of PHD17 increased cold tolerance,partially via the CBF cold signaling.By combining transcriptomic and physiological analyses,we demonstrated that PHD17 modulated ROS homeostasis and flavonoid accumulation under cold stress.K-means clustering analysis revealed that differentially expressed genes in PHD17 transgenic lines were significantly enriched in the jasmonic acid(JA)biosynthesis pathway,and expression of JA biosynthesis and signaling genes was verified to be affected by PHD17.Cold stress tests applied with MeJA or IBU(JA synthesis inhibitor)further suggested the involvement of PHD17 in JA-mediated cold signaling.Taken together,our results suggest that PHD17 acts downstream of miR1320 and negatively regulates cold tolerance of rice seedlings through JA-mediated signaling pathway. 展开更多
关键词 RICE Cold tolerance PHD protein miR1320 JA signaling
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Role of land-atmosphere coupling in persistent extreme climate events in eastern China in summer 2022
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作者 yue chen Aihui Wang 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第2期19-26,共8页
2022年暖季,中国东部地区遭受持续性高温,少雨和土壤干旱的复合极端事件.特征分析指出,在研究时段内,中国东部地区的气温,降水和土壤湿度呈现明显的季节内变化和南北差异。由1940-2022年的气候态可知,长江流域和东南地区的土壤含水充足... 2022年暖季,中国东部地区遭受持续性高温,少雨和土壤干旱的复合极端事件.特征分析指出,在研究时段内,中国东部地区的气温,降水和土壤湿度呈现明显的季节内变化和南北差异。由1940-2022年的气候态可知,长江流域和东南地区的土壤含水充足,蒸散主要受限于陆面有效能量.然而,潜在机制研究指出,2022年土壤湿度对蒸散的限制作用在上述区域异常偏强,土壤湿度与气候要素之间的强反馈可能在2022年复合极端事件的演变和持续中发挥了关键作用。 展开更多
关键词 复合极端事件 陆气耦合 土壤湿度 干旱 中国东部
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Degradation of FAK-targeting by proteolytic targeting chimera technology to inhibit the metastasis of hepatocellular carcinoma
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作者 XINFENG ZHANG SHUANG LI +8 位作者 MEIRU SONG yue chen LIANGZHENG CHANG ZHERUI LIU HONGYUAN DAI YUTAO WANG GANGQI YANG YUN JIANG YINYING LU 《Oncology Research》 SCIE 2024年第4期679-690,共12页
Liver cancer is a prevalent malignant cancer,ranking third in terms of mortality rate.Metastasis and recurrence primarily contribute to the high mortality rate of liver cancer.Hepatocellular carcinoma(HCC)has low expr... Liver cancer is a prevalent malignant cancer,ranking third in terms of mortality rate.Metastasis and recurrence primarily contribute to the high mortality rate of liver cancer.Hepatocellular carcinoma(HCC)has low expression of focal adhesion kinase(FAK),which increases the risk of metastasis and recurrence.Nevertheless,the efficacy of FAK phosphorylation inhibitors is currently limited.Thus,investigating the mechanisms by which FAK affects HCC metastasis to develop targeted therapies for FAK may present a novel strategy to inhibit HCC metastasis.This study examined the correlation between FAK expression and the prognosis of HCC.Additionally,we explored the impact of FAK degradation on HCC metastasis through wound healing experiments,transwell invasion experiments,and a xenograft tumor model.The expression of proteins related to epithelial-mesenchymal transition(EMT)was measured to elucidate the underlying mechanisms.The results showed that FAK PROTAC can degrade FAK,inhibit the migration and invasion of HCC cells in vitro,and notably decrease the lung metastasis of HCC in vivo.Increased expression of E-cadherin and decreased expression of vimentin indicated that EMT was inhibited.Consequently,degradation of FAK through FAK PROTAC effectively suppressed liver cancer metastasis,holding significant clinical implications for treating liver cancer and developing innovative anti-neoplastic drugs. 展开更多
关键词 Hepatocellular carcinoma(HCC) Focal adhesion kinase(FAK) Proteolytic targeting chimera technology(PROTAC) Epithelial-mesenchymal transformation(EMT) METASTASIS
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A dual-route optical emission spectroscopy diagnostic with wide spectral range and high wavelength resolution on HL-2A tokamak
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作者 陈越 高继昆 +10 位作者 龙婷 聂林 高金明 马尧 黄渊 田文静 刘延民 朱晓东 庄革 钟武律 许敏 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期25-30,共6页
A dual-route optical emission spectroscopy(D-OES)diagnostic is newly developed to monitor the optical emission from the X-point plasma region on the HL-2 A tokamak.This diagnostic is composed of an imaging system,a be... A dual-route optical emission spectroscopy(D-OES)diagnostic is newly developed to monitor the optical emission from the X-point plasma region on the HL-2 A tokamak.This diagnostic is composed of an imaging system,a beam-splitting system for dual-route measurements,fiber bundles,a spectrometer system,and a control and acquisition system.One route is used to obtain wide-spectral-range spectra,and the other route is used to acquire high-wavelengthresolution line shapes.The spectral resolution of the wide-range spectrometers is 0.8 nm with a coverage of 800 nm(@200-1000 nm).The spectral resolution of the high-resolution spectrometer is 0.01 nm with a coverage of 6 nm(@200-660 nm).The spatial resolution of each route of D-OES is about 4 cm with 11 channels.The temporal resolution is 16 ms at maximum in the single-channel mode.Wide-range spectra(containing Balmer series and a Fulcher band)and highly resolved Ha line shapes are obtained by D-OES in the hydrogen glow discharge in the lab.D-OES measurements are carried out in the high-density deuterium experiments of HL-2A.The electron density n_(e)and deuterium temperature T_(D) in the X-point multifaceted asymmetric radiation from the edge(MARFE)region are derived simultaneously by fitting the measured D_(a) shape.The density n_(e)is observed to increase from~8.7×10^(18)m^(-3)to~7.8×10^(19)m^(-3),and the temperature T_(D)drops from~14.4 eV to~2.3 eV after the onset of MARFE in the discharge#38260. 展开更多
关键词 optical emission spectroscopy Balmer series TOKAMAK
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Midpoint transverse process to pleura block for postoperative analgesia following laparoscopic renal cyst decortication:Two case reports
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作者 Wei-Jie He Wen-Xing Xu +4 位作者 Xu-Dong Zhang yue chen Shu-Ying He Xian-Qin Wei Xiao-Lan Huang 《World Journal of Clinical Cases》 SCIE 2024年第18期3629-3635,共7页
BACKGROUND The midpoint transverse process to pleura(MTP)block,a novel technique for thoracic paravertebral block(TPVB),was first employed in laparoscopic renal cyst decortication.CASE SUMMARY Thoracic paravertebral n... BACKGROUND The midpoint transverse process to pleura(MTP)block,a novel technique for thoracic paravertebral block(TPVB),was first employed in laparoscopic renal cyst decortication.CASE SUMMARY Thoracic paravertebral nerve block is frequently employed for perioperative analgesia during laparoscopic cyst decortication.To address safety concerns associated with TPVBs,we administered MTP blocks in two patients prior to administering general anesthesia for laparoscopic cyst decortication.The MTP block was performed at the T9 level under ultrasound guidance,with 20 mL of 0.5%ropivacaine injected.Reduced sensation to cold and pinprick was observed from the T8 to T11 dermatome levels.Immediately postoperative Numeric Pain Rating Scale scores were 0/10 at rest and on movement,with none exceeding a mean 24 h numeric rating scale>3.CONCLUSION MTP block was effective technique for providing postoperative analgesia for patients undergoing laparoscopic renal cyst decortication. 展开更多
关键词 Midpoint transverse process to pleura block Laparoscopic renal cyst decortication PAIN ANALGESIA Case report
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Study on improving hematopoietic function of rats with blood deficiency syndrome by Shengxuebao mixture
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作者 Yan Shu Hong-Na Liu +5 位作者 Yang Zhao Jin-Yi Cao yue chen Yi Qiao Hui Guo Zhi-Fu Yang 《Traditional Medicine Research》 2024年第8期35-46,共12页
Background:Shengxuebao mixture(SXBM)is a novel herbal drug approved by China State Food and Drug Administration for the treatment of Leukopenia and iron deficiency anemia caused by radiotherapy and chemotherapy.Method... Background:Shengxuebao mixture(SXBM)is a novel herbal drug approved by China State Food and Drug Administration for the treatment of Leukopenia and iron deficiency anemia caused by radiotherapy and chemotherapy.Methods:To explore the mechanism of SXBM in treating blood deficiency syndrome(BDS).Firstly,network pharmacology and in vivo experiments were used to screen candidate targets and important signaling pathways of SXBM,GO functional enrichment and KEGG pathway analysis were performed.Secondly,a BDS rat model was established to verify the results of the analysis of network pharmacological enrichment.Histopathology and routine peripheral blood examination were observed.The expressions of tumor necrosis factor-α,interleukin(IL)-6,HIF-1αand NF-κB were detected by Western blot,and the expressions of IL-6,IL-1βwere detected by ELISA.Results:62 bioactive components,66 potential targets and 131 signaling pathways of BDS were successfully identified by network pharmacology.Molecular docking simulation techniques showed that key targets tumor necrosis factor-α,IL-6,IL-1βcan dock well with crucial components,and the BDS-related signaling pathways HIF-1 and JAK-STAT play a vital role.The combined model experiment of acetylphenylhydrazine and cyclophosphamide showed that the model group had obvious blood deficiency,and the histopathology and blood routine were effectively restored after administration.Our findings indicate that SXBM’s therapeutic effect on BDS primarily involves the mediation of the HIF-1α/NF-κB signaling pathway and the regulation of hematopoietic factor expression.Conclusion:This study not only affirmed the protective properties of SXBM against BDS but also provided insights into a potential mechanism for blood replenishment in the treatment of BDS using SXBM. 展开更多
关键词 network pharmacology molecular docking technology blood deficiency syndrome hematopoietic factors HIF-1α/NF-κB
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离子液体镀铝工艺在纵向解锁机构弹簧上的应用研究
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作者 乐晨 张联英 +3 位作者 郭嘉 宋启良 张毅博 王明杰 《宇航材料工艺》 CAS CSCD 北大核心 2024年第2期112-118,共7页
纵向解锁机构是一套用于运载火箭整流罩两半罩连接与分离用的机构产品,其核心组件锁钩在验收和总装过程中需要重复多次解锁装配,弹簧是锁钩分离时使用的驱动元件。为提高弹簧可靠性,本文研究使用离子液体镀铝工艺替代含有氢脆隐患的电... 纵向解锁机构是一套用于运载火箭整流罩两半罩连接与分离用的机构产品,其核心组件锁钩在验收和总装过程中需要重复多次解锁装配,弹簧是锁钩分离时使用的驱动元件。为提高弹簧可靠性,本文研究使用离子液体镀铝工艺替代含有氢脆隐患的电镀锌进行表面处理。首先通过典型产品试镀形成工艺方法,随后进行弹簧试制,最后开展热环境和锁钩机构试验验证弹簧可靠性。结果表明,离子液体镀铝工艺中的喷丸工艺会导致弹簧力值略微下降;这种状态的弹簧能够满足环境适应性要求,重复解锁会造成弹簧镀层磨损,力值下降约5%,但仍满足设计要求。弹簧使用离子镀铝工艺表面处理能够替代电镀锌,工艺实施过程中的喷丸后处理需要严格控制,重复使用时对弹簧镀层和力值的影响需要关注。 展开更多
关键词 离子液体镀铝 纵向解锁机构 弹簧
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Leukopenia-a rare complication secondary to invasive liver abscess syndrome in a patient with diabetes mellitus:A case report
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作者 Chun-Yan Niu Bang-Tao Yao +4 位作者 Hua-Yi Tao Xin-Gui Peng Qing-Hua Zhang yue chen Lu Liu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第10期3343-3349,共7页
BACKGROUND Thrombocytopenia is a common complication of invasive liver abscess syndrome(ILAS)by Klebsiella pneumoniae(K.pneumoniae)infection,which indicates severe infection and a poor prognosis.However,the presence o... BACKGROUND Thrombocytopenia is a common complication of invasive liver abscess syndrome(ILAS)by Klebsiella pneumoniae(K.pneumoniae)infection,which indicates severe infection and a poor prognosis.However,the presence of leukopenia is rare.There are rare reports on leukopenia and its clinical significance for ILAS,and there is currently no recognized treatment plan.Early and broad-spectrum antimi-crobial therapy may be an effective therapy for treating ILAS and improving its prognosis.CASE SUMMARY A 55-year-old male patient who developed fever,chills,and abdominal distension without an obvious cause presented to the hospital for treatment.Laboratory tests revealed thrombocytopenia,leukopenia,and multiple organ dysfunction.Imaging examinations revealed an abscess in the right lobe of the liver and thromboph-lebitis,and K.pneumoniae was detected in the blood cultures.Since the patient was diabetic and had multi-system involvement,he was diagnosed with ILAS accom-panied by leukopenia and thrombocytopenia.After antibiotic treatment and sys-temic supportive therapy,the symptoms disappeared,and the patient’s condition almost completely resolved.CONCLUSION Leukopenia is a rare complication of ILAS,which serves as an indicator of adverse prognostic outcomes and the severity of infection. 展开更多
关键词 Invasive liver abscess syndrome Klebsiella pneumoniae LEUKOPENIA THROMBOCYTOPENIA Treatment Prognosis Case report
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Normal pregnancy outcome after first-trimester exposure to semaglutide in an overweight woman: a case report
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作者 Xi-Mei Zhu Qian-Yun Huang +2 位作者 yue chen Ying Zhou Cai-Hua Yang 《Clinical Research Communications》 2024年第2期30-33,共4页
We reported a case of an overweight 34-year-old woman who unexpectedly became pregnant while undergoing semaglutide in early pregnancy and delivered a healthy male infant by caesarean section at 37 weeks and 4 days of... We reported a case of an overweight 34-year-old woman who unexpectedly became pregnant while undergoing semaglutide in early pregnancy and delivered a healthy male infant by caesarean section at 37 weeks and 4 days of gestation.Until now,the safety of semaglutide for use during pregnancy was unknown.This report may contribute to the limited knowledge available on pregnant women exposure to semaglutide. 展开更多
关键词 case report glucagon-like peptide-1 receptor agonist semaglutide normal pregnancy outcome
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基于人工智能的科研管理模式探讨
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作者 陈越 孟庆禹 +2 位作者 侯兴旺 李京洋 于航 《产业科技创新》 2024年第3期83-86,共4页
人工智能技术的蓬勃发展为科研管理模式变革带来新的契机,本文在分析了现有科研管理模式面向人工智能转型过程中面临的3个主要问题的基础上,对基于人工智能的科研管理新范式展开探讨,并从政策体系的建立、科研管理人员的培养以及隐私安... 人工智能技术的蓬勃发展为科研管理模式变革带来新的契机,本文在分析了现有科研管理模式面向人工智能转型过程中面临的3个主要问题的基础上,对基于人工智能的科研管理新范式展开探讨,并从政策体系的建立、科研管理人员的培养以及隐私安全和科技伦理等方面为促进人工智能赋能科研管理等提出相关对策建议。 展开更多
关键词 科研管理 人工智能 体制改革 科研管理决策
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三级淋巴结构在非小细胞肺癌预后及免疫治疗中的研究进展 被引量:1
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作者 刘颖 熊磊 +4 位作者 蔡若雪 陈越 叶劲军 沈波 周国仁 《中国肺癌杂志》 CAS CSCD 北大核心 2023年第8期615-620,共6页
肺癌是当前癌症死亡的首要原因,其中非小细胞肺癌(non-small cell lung cancer,NSCLC)占肺癌的85%。免疫治疗显著改善了NSCLC患者的临床预后,但肿瘤微环境具有复杂性和异质性,仍有部分患者不能受益于免疫治疗,因此有必要探索NSCLC免疫... 肺癌是当前癌症死亡的首要原因,其中非小细胞肺癌(non-small cell lung cancer,NSCLC)占肺癌的85%。免疫治疗显著改善了NSCLC患者的临床预后,但肿瘤微环境具有复杂性和异质性,仍有部分患者不能受益于免疫治疗,因此有必要探索NSCLC免疫治疗的有效预测生物标志物。三级淋巴结构(tertiary lymphoid structure,TLS)是与次级淋巴器官(secondary lymphoid organs,SLO)高度相似的异位淋巴器官,有研究发现TLS的存在与多种实体瘤(包括NSCLC)免疫治疗的良好预后密切相关。本文对TLS在NSCLC预后及免疫治疗中的作用进行综述,为筛选NSCLC免疫治疗适宜人群及制定个性化、精准化治疗方案提供参考。 展开更多
关键词 三级淋巴结构 肺肿瘤 免疫治疗
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太阳纳米光子蒸馏膜的性能特性分析
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作者 岳晨 曹友坤 彭有德 《太阳能学报》 EI CAS CSCD 北大核心 2023年第11期147-154,共8页
为有效改善蒸馏膜(MD)的高能耗问题,提出一种低能耗的太阳纳米光子蒸馏膜(NESMD)组件,对其热力学性能开展研究,并分析关键操作参数对其热力学特性的影响规律。研究结果表明,温度极化是导致MD技术高能耗的主要内因,NESMD组件采用面加热... 为有效改善蒸馏膜(MD)的高能耗问题,提出一种低能耗的太阳纳米光子蒸馏膜(NESMD)组件,对其热力学性能开展研究,并分析关键操作参数对其热力学特性的影响规律。研究结果表明,温度极化是导致MD技术高能耗的主要内因,NESMD组件采用面加热方式进行料液加热,不存在温度极化现象,因此具有显著的节能优势。在相同进料温度和进料速度下,NESMD组件相较于MD组件,温度极化系数和热效率均有显著提升,NESMD组件热效率受潜热影响最大,可采取低进料速度和高进料温度来提高热效率;当将聚乙烯醇(PVA)涂层作为功率输入段时,NESMD和MD组件均存在最佳输入段长度使得热效率最大;NESMD组件相较于MD组件具有更好的拓展性和更长的活性长度。上述性能规律为进一步优化结构提供了科学依据。 展开更多
关键词 太阳能 蒸馏膜 温度极化 纳米光子 热效率 活性长度
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2型糖尿病合并白内障患者晶状体上皮细胞中PEDF和VEGF的表达及意义 被引量:4
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作者 胡亚茹 陈悦 +3 位作者 韩雪 陈亚茹 马竹宇 王剑锋 《国际眼科杂志》 CAS 北大核心 2023年第1期109-112,共4页
目的:观察糖尿病合并年龄相关性白内障患者晶状体上皮细胞(LECs)中色素上皮衍生因子(PEDF)、血管内皮细胞生长因子(VEGF)的表达水平,探讨糖尿病合并年龄相关性白内障的发病机制。方法:回顾性研究。收集2020-08/2021-04在蚌埠医学院第一... 目的:观察糖尿病合并年龄相关性白内障患者晶状体上皮细胞(LECs)中色素上皮衍生因子(PEDF)、血管内皮细胞生长因子(VEGF)的表达水平,探讨糖尿病合并年龄相关性白内障的发病机制。方法:回顾性研究。收集2020-08/2021-04在蚌埠医学院第一附属医院眼科就诊的年龄相关性白内障和2型糖尿病合并年龄相关性白内障患者各30例。所有患者白内障超声乳化术中收取术眼晶状体中央区5.5~6.0mm直径的前囊膜标本,采用蛋白免疫印迹法(Western-blot)检测LECs中PEDF、VEGF蛋白表达水平。实时荧光定量PCR(qRT-PCR)方法检测PEDF、VEGF mRNA的相对表达量。结果:两组患者LECs中均存在PEDF、VEGF的表达,2型糖尿病合并年龄相关性白内障组患者VEGF mRNA相对表达量为1.364±0.062,高于年龄相关性白内障组的1.000±0.0(P<0.01),PEDF mRNA的相对表达量为0.398±0.053,明显低于年龄相关性白内障组的1.000±0.0(P<0.001)。2型糖尿病合并年龄相关性白内障组患者LECs中VEGF和PEDF蛋白表达量为2.053±0.026、0.579±0.045,年龄相关性白内障组为1.680±0.064、1.058±0.007(均P<0.01)。结论:2型糖尿病合并年龄相关性白内障患者LECs中PEDF和VEGF表达水平发生变化,可能与糖尿病患者白内障的发生和发展有关。 展开更多
关键词 糖尿病合并白内障 晶状体上皮细胞(LECs) 色素上皮衍生因子(PEDF) 血管内皮细胞生长因子(VEGF)
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细胞焦亡相关因子在类风湿关节炎患者中的表达及意义 被引量:6
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作者 王秋苑 刘又文 +2 位作者 岳辰 侯宏理 张雪 《中国组织工程研究》 CAS 北大核心 2023年第32期5209-5213,共5页
背景:类风湿关节炎是常见的自身免疫性疾病,主要侵犯机体关节部位,特征为持续性滑膜炎症,研究提示促炎性的细胞焦亡与类风湿关节炎疾病的发生发展密切相关。目的:明确类风湿关节炎患者血清和关节液中细胞焦亡相关因子NOD样受体蛋白3、... 背景:类风湿关节炎是常见的自身免疫性疾病,主要侵犯机体关节部位,特征为持续性滑膜炎症,研究提示促炎性的细胞焦亡与类风湿关节炎疾病的发生发展密切相关。目的:明确类风湿关节炎患者血清和关节液中细胞焦亡相关因子NOD样受体蛋白3、半胱氨酸天冬氨酸蛋白酶1、白细胞介素18及白细胞介素1β的表达水平及其临床意义。方法:选择2021年1月至2022年1月河南省洛阳正骨医院(河南省骨科医院)风湿病科收治的类风湿关节炎患者24例(类风湿关节炎组),同期选取伴膝关节积液的骨关节炎患者30例(骨关节炎组),健康受试者40例(对照组)。检测并记录3组受试者的C-反应蛋白、红细胞沉降率、抗环瓜氨酸肽抗体、类风湿因子水平和类风湿关节炎28个关节疾病活动度评分。采用酶联免疫吸附法测定血清和关节液中NOD样受体蛋白3、半胱氨酸天冬氨酸蛋白酶1、白细胞介素18及白细胞介素1β的表达水平,分析上述4项因子表达水平与类风湿关节炎患者临床指标之间的相关性。结果与结论:①类风湿关节炎组患者血清中的NOD样受体蛋白3、半胱氨酸天冬氨酸蛋白酶1、白细胞介素18及白细胞介素1β水平显著高于对照组(P<0.0001),关节液中NOD样受体蛋白3、半胱氨酸天冬氨酸蛋白酶1、白细胞介素18及白细胞介素1β水平显著高于骨关节炎组(P<0.05-0.01);②类风湿关节炎患者血清和关节液中NOD样受体蛋白3、半胱氨酸天冬氨酸蛋白酶1、白细胞介素18及白细胞介素1β的表达水平分别与类风湿关节炎患者的类风湿关节炎28个关节疾病活动度评分、C-反应蛋白和红细胞沉降率水平呈正相关;③提示细胞焦亡相关因子在类风湿关节炎患者中明显升高,且与疾病活动度相关,提示细胞焦亡可能在类风湿关节炎发病中发挥作用。 展开更多
关键词 类风湿关节炎 细胞焦亡 血清 关节液 炎性因子 疾病活动度
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一种蒸发式凹腔驻涡值班稳定器的流动与点火性能研究
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作者 于文博 范育新 +1 位作者 岳晨 邓宇 《推进技术》 EI CAS CSCD 北大核心 2023年第5期108-117,共10页
为进一步拓宽凹腔驻涡值班稳定器在低温、高速来流条件下的点熄火边界,提出了一种利用高温燃气预热、预混供油的蒸发式凹腔驻涡值班稳定器。研究了蒸发式凹腔驻涡值班稳定器的流动特性、燃油分布特性及点火性能。研究结果表明:蒸发式凹... 为进一步拓宽凹腔驻涡值班稳定器在低温、高速来流条件下的点熄火边界,提出了一种利用高温燃气预热、预混供油的蒸发式凹腔驻涡值班稳定器。研究了蒸发式凹腔驻涡值班稳定器的流动特性、燃油分布特性及点火性能。研究结果表明:蒸发式凹腔驻涡值班稳定器的掺混腔和凹腔内部形成的涡系结构为低温、高速来流下的点火和燃烧提供了有利条件。凹腔驻涡区的气相油雾沿流向分布均匀,沿周向从稳定器对称子午面最富递减到相邻稳定器中间面最贫。在相同来流温度下,蒸发式凹腔驻涡值班稳定器的贫油点火和熄火当量比均随着来流速度的增大而增大。在低温(600K)、高速(100~200m/s)来流条件下,相比于蒸发式Z形值班火焰稳定器和常规薄膜蒸发式火焰稳定器,蒸发式凹腔驻涡值班稳定器贫油点火当量比能分别降低5.5%和30%;其贫油熄火当量比能分别降低37.4%和48.8%。 展开更多
关键词 加力/冲压多模态燃烧室 凹腔驻涡 值班稳定器 流动特性 点火性能 当量比
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