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High-temperature thin-film strain sensors with low temperature coefficient of resistance and high sensitivity via direct ink writing
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作者 Lida Xu Fuxin Zhao +10 位作者 Xiong Zhou Yusen Wang Tingting Shen Jun Liu Haidong Wang Guo Yi Xingguang Zhou Chao Wu Yang Zhao Daoheng Sun Qinnan Chen 《Nanotechnology and Precision Engineering》 2025年第1期1-9,共9页
High-temperature thin-film strain sensors are advanced technological devices for monitoring stress and strain in extreme environments,but the coupling of temperature and strain at high temperature is a challenge for t... High-temperature thin-film strain sensors are advanced technological devices for monitoring stress and strain in extreme environments,but the coupling of temperature and strain at high temperature is a challenge for their use.Here,this issue is addressed by creating a composite ink that combines Pb_(2)Ru_(2)O_(6) and TiB_(2) using polysilazane(PSZ)as a binder.After direct writing and annealing the PSZ/Pb_(2)Ru_(2)O_(6)/TiB_(2) film at 800℃ in air,the resulting thin film exhibits a low temperature coefficient of resistance(TCR)of only 281 ppm/℃ over a wide temperature range from 100℃ to 700℃,while also demonstrating high sensitivity with a gauge factor approaching 19.8.This exceptional performance is attributed to the intrinsic properties of Pb_(2)Ru_(2)O_(6),which has positive TCR at high temperature,and TiB2,which has negative TCR at high temperature.Combining these materials reduces the overall TCR of the film.Tests showed that the PSZ/Pb_(2)Ru_(2)O_(6)/TiB_(2) film maintains stable strain responses and significant signal output even under varying temperature.These findings provide valuable insights for developing high-temperature strain sensors with low TCR and high sensitivity,highlighting their potential for applications in high-temperature strain measurements. 展开更多
关键词 High-temperature thinfilm Strain sensor Direct ink writing Low temperature coefficient of resistance High sensitivity
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Species-specific influences of competition and tree size on drought sensitivity and resistance for three planted conifers in northern China
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作者 Rui Deng Jinglei Liao +5 位作者 Tim Rademacher Zhongqi Xu Mingchao Du Jianwei Zheng Lihua Fu Xianliang Zhang 《Forest Ecosystems》 2025年第3期402-410,共9页
Droughts have caused tree growth decline and high tree mortality across temperate forests,however,how to manage planted forests to alleviate drought stress is still challenging.We used tree-ring and forest inventory d... Droughts have caused tree growth decline and high tree mortality across temperate forests,however,how to manage planted forests to alleviate drought stress is still challenging.We used tree-ring and forest inventory data from different density stands to investigate how competition,tree diameter at breast height(DBH),tree age,and their interactions influence drought sensitivity and resistance for three widely-distributed and planted conifer species(Larix principis-rupprechtii,Picea meyeri,and Pinus sylvestris var.mongolica).Our results showed that the drought sensitivity of the three species was influenced by competition,tree size,and their interactions.Large L.principis-rupprechtii trees were particularly sensitive to drought during the growing season in medium to high-density stands,while the growth of large P.sylvestris var.mongolica was most affected by precipitation at low to medium density stands.Drought resistance of L.principis-rupprechtii trees decreased as tree size increased.Large L.principis-rupprechtii trees had lower drought resistance than small trees in all stands.Drought resistance of large P.meyeri trees exhibited high resistance to drought only in high-density stands.However,drought resistance of P.sylvestris var.mongolica trees was affected by tree size,competition,and their interactions.These results indicated that targeted silvicultural interventions,such as thinning,can be implemented to enhance drought resistance specifically for large L.principis-rupprechtii trees and small P.sylvestris var.mongolica trees in medium and high competition stands,and small P.meyeri trees in high competition stands.Our results highlight that properly conducted thinning can in some cases enhance growth resistance to droughts,depending on stand density,tree size,and tree species. 展开更多
关键词 COMPETITION Tree size Radial growth Drought events Drought sensitivity
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Mechanisms underlying prostate cancer sensitivity to reactive oxygen species:overcoming radiotherapy resistance and recent clinical advances
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作者 Meidan Wang Rui Xing +5 位作者 Liqun Wang Mingyue Pan Ruoyun Zhang Ting Li Weiqiang Sun Jing Zhou 《Cancer Biology & Medicine》 2025年第7期747-761,共15页
Prostate cancer(PCa)is a leading cause of cancer-related mortality among men.Radiotherapy is the cornerstone of PCa treatment.However,a major limitation of radiotherapy is the development of resistance,which compromis... Prostate cancer(PCa)is a leading cause of cancer-related mortality among men.Radiotherapy is the cornerstone of PCa treatment.However,a major limitation of radiotherapy is the development of resistance,which compromises treatment efficacy.Reactive oxygen species(ROS),which are generated by radiation,have a dual role in PCa by inducing DNA damage and apoptosis,while also promoting tumor progression and radioresistance.Elevated ROS levels enhance metabolic reprogramming,activate oncogenic pathways,and influence the tumor microenvironment by modulating immune responses and promoting the epithelial-mesenchymal transition(EMT).Key molecular mechanisms,including the Nrf2/Keap1 signaling axis,Bcl-2 mutations,and Speckle-type POZ protein alterations,contribute to radioresistance by enhancing antioxidant defenses and DNA repair capacity.Additionally,the interplay between hypoxia,androgen receptor variants(AR-Vs),and ferroptosis regulators further influence radiotherapy outcomes.Understanding these resistance mechanisms is crucial for developing targeted strategies to enhance radiosensitivity and improve therapeutic outcomes in PCa patients. 展开更多
关键词 Prostate cancer(PCa) radiation therapy(RT) reactive oxygen species(ROS) radiotherapy resistance ANTIOXIDANTS
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Dual carbapenem-fluoroquinolone resistance in community-onset pediatric urinary tract infections:Phenotypic-genotypic integration in three cases
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作者 C Quang Ngo D Hung Tran +2 位作者 T Trung Huynh Q Nhu Nguyen H My Le 《Asian Pacific Journal of Tropical Medicine》 2026年第1期45-48,共4页
Urinary tract infections(UTIs)are among the most prevalent pediatric bacterial infections,and undertreated episodes may lead to renal scarring,hypertension,or chronic kidney disease.Multidrug-resistant(MDR)Enterobacte... Urinary tract infections(UTIs)are among the most prevalent pediatric bacterial infections,and undertreated episodes may lead to renal scarring,hypertension,or chronic kidney disease.Multidrug-resistant(MDR)Enterobacterales have been increasingly reported in children,with higher rates in Asian and Middle Eastern settings than in high-income countries[1,2]. 展开更多
关键词 phenotypic genotypic integration chronic kidney diseasemultidrug resistant mdr enterobacterales community onset pediatric urinary tract infections renal scarring urinary tract infections dual carbapenem fluoroquinolone resistance multidrug resistant enterobacterales
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The Role of Exosomes as a Key Factor of Cytostatic Resistance in Cancer:Mechanisms of Action,Potential Biomarkers,and Possible Exosome-Based Therapies
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作者 Sandra Kałużna MonikaŚwierczewska +3 位作者 Sylwia Ciesiółka Małgorzata Partyka MichałNowicki Karolina Wojtowicz 《Oncology Research》 2026年第1期23-56,共34页
The last research focuses on the role of exosomes in cancer treatment.Exosomes are extracellular vesicles.They can be secreted by cancer cells,and they can modulate chemotherapy sensitivity.Determining exosomal conten... The last research focuses on the role of exosomes in cancer treatment.Exosomes are extracellular vesicles.They can be secreted by cancer cells,and they can modulate chemotherapy sensitivity.Determining exosomal content opens the possibility for guiding treatment strategies for cancer diseases.Exosomal microRNA are considered one of the prime candidates for exosomal biomarkers.Exosomal circular RNAs represent excellent biomarkers for liquid biopsy because of their stability in many types of cancer.Exosomal proteins remain reliable biomarkers also.Exosomes have emerged as promising therapeutic candidates.Their biological properties render them ideal vectors for drug delivery.Genetic modification of exosomes is an effective way to deliver material capable of modulating cellular pathways involved in drug resistance.Furthermore,exosomes have been explored as carriers for metal-chelating agents.Integrating exosome-based therapies with traditional anticancer agents aims to exploit the natural targeting abilities of exosomes to enhance drug delivery.Despite the dynamic development of this field,many mechanisms of exosome action remain incompletely understood.Therefore,it is necessary to conduct further studies that will allow for a better understanding of their role in the process of resistance and will enable the development of effective therapeutic strategies. 展开更多
关键词 EXOSOMES drug resistance CANCER
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Prevalence of serotypes,antibiotic resistance and virulence genes of Group B Streptococcus isolated from pregnant women at 35-37 weeks of gestation in Ho Chi Minh City,Vietnam
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作者 Truc-Anh Nguyen-Thi Hong-Phuc Nguyen +3 位作者 Thien-An Do-Hoang Minh-Hoang Tran Tuan-Loc Le Hieu Vu-Quang 《Asian Pacific Journal of Tropical Medicine》 2026年第1期16-24,共9页
Objective:To analyse the prevalence of serotypes,antibiotic resistance,and virulence genes of Group B Streptococcus(GBS)strains isolated from pregnant women at 35-37 weeks of gestation in Ho Chi Minh City,Vietnam,from... Objective:To analyse the prevalence of serotypes,antibiotic resistance,and virulence genes of Group B Streptococcus(GBS)strains isolated from pregnant women at 35-37 weeks of gestation in Ho Chi Minh City,Vietnam,from January 2022 to January 2023.Methods:GBS strains were isolated through selective culture methods and confirmed by PCR.Serotyping,virulence gene detection,and antibiotic susceptibility testing were performed using PCR,gel electrophoresis techniques and Kirby-Bauer test.Results:Totally,61 GBS isolated from 300 participants have been identified including seven GBS serotypes(Ⅰa,Ⅰb,Ⅱ,Ⅲ,Ⅳ,Ⅴ,andⅥ).SerotypesⅦ,Ⅷ,andⅨwere not detected in the study population.Antibiotic resistance patterns varied:13.1%of isolates were fully susceptible,while the majority showed multi-drug resistance,with 34.4%resistant to three antibiotics.SerotypeⅠa demonstrated high susceptibility(35.7%),while serotypeⅢshowed extensive resistance,with 87.5%being resistant to at least three antibiotics.All strains are susceptible to vancomycin andβ-lactams susceptibility also remained high,but resistance to clindamycin,erythromycin,and tetracycline was high(>65%).The virulence genes scpB,cylB,fbsB,and cfb were highly prevalent(90%-100%),indicating their potential for vaccine and diagnostic development.Conclusions:Our findings provide valuable insights into GBS serotypes,resistance,and virulence factors,contributing to community monitoring,preventive measures,diagnostics,and vaccine development.However,the limited sample size necessitates further research. 展开更多
关键词 Group B Streptococcus SEROTYPE Antibiotic resistance VIRULENCE PREGNANCY
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A novel approach to identify the spatial characteristics of ozone-precursor sensitivity based on interpretable machine learning
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作者 Huiling He Kaihui Zhao +6 位作者 Zibing Yuan Jin Shen Yujun Lin Shu Zhang Menglei Wang Anqi Wang Puyu Lian 《Journal of Environmental Sciences》 2026年第1期54-63,共10页
To curb the worsening tropospheric ozone(O_(3))pollution problem in China,a rapid and accurate identification of O_(3)-precursor sensitivity(OPS)is a crucial prerequisite for formulating effective contingency O_(3) po... To curb the worsening tropospheric ozone(O_(3))pollution problem in China,a rapid and accurate identification of O_(3)-precursor sensitivity(OPS)is a crucial prerequisite for formulating effective contingency O_(3) pollution control strategies.However,currently widely-used methods,such as statistical models and numerical models,exhibit inherent limitations in identifying OPS in a timely and accurate manner.In this study,we developed a novel approach to identify OPS based on eXtreme Gradient Boosting model,Shapley additive explanation(SHAP)al-gorithm,and volatile organic compound(VOC)photochemical decay adjustment,using the meteorology and speciated pollutant monitoring data as the input.By comparing the difference in SHAP values between base sce-nario and precursor reduction scenario for nitrogen oxides(NO_(x))and VOCs,OPS was divided into NO_(x)-limited,VOCs-limited and transition regime.Using the long-lasting O_(3) pollution episode in the autumn of 2022 at the Guangdong-Hong Kong-Macao Greater Bay Area(GBA)as an example,we demonstrated large spatiotemporal heterogeneities of OPS over the GBA,which were generally shifted from NO_(x)-limited to VOCs-limited from September to October and more inclined to be VOCs-limited at the central and NO_(x)-limited in the peripheral areas.This study developed an innovative OPS identification method by comparing the difference in SHAP value before and after precursor emission reduction.Our method enables the accurate identification of OPS in the time scale of seconds,thereby providing a state-of-the-art tool for the rapid guidance of spatial-specific O_(3) control strategies. 展开更多
关键词 O_(3)-precursor sensitivity Machine learning Extreme gradient boosting model Shapley algorithm Greater bay area
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High-temperature oxidation resistance of TiB_(2)coatings on molybdenum produced by molten salt electrophoretic deposition
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作者 Qian Kou Chuntao Ge +6 位作者 Yanlu Zhou Wenjuan Qi Junjie Xu Weiliang Jin Jun Zhang Hongmin Zhu Saijun Xiao 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期282-291,共10页
TiB_(2)coatings can significantly enhance the high-temperature oxidation resistance of molybdenum,which would broaden the application range of molybdenum and alloys thereof.However,traditional methods for preparing Ti... TiB_(2)coatings can significantly enhance the high-temperature oxidation resistance of molybdenum,which would broaden the application range of molybdenum and alloys thereof.However,traditional methods for preparing TiB_(2)coatings have disadvantages such as high equipment costs,complicated processes,and highly toxic gas emissions.This paper proposes an environmentally friendly method,which requires inexpensive equipment and simple processing,for preparing TiB_(2)coating on molybdenum via electrophoretic deposition within Na3AlF6-based molten salts.The produced TiB_(2)layer had an approximate thickness of 60μm and exhibited high density,outstanding hardness(38.2 GPa)and robust adhesion strength(51 N).Additionally,high-temperature oxidation experiments revealed that,at900℃,the TiB_(2)coating provided effective protection to the molybdenum substrate against oxidation for 3 h.This result indicates that the TiB_(2)coating prepared on molybdenum using molten salt electrophoretic deposition possesses good high-temperature oxidation resistance. 展开更多
关键词 molten salt electrophoretic deposition MOLYBDENUM TiB_(2)coating high-temperature oxidation resistance
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Brain insulin resistance and neuropsychiatric symptoms in Alzheimer's disease:A role for dopamine signaling
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作者 Anastasia Kontogianni Hongbin Yang Wenqiang Chen 《Neural Regeneration Research》 2026年第5期1995-1996,共2页
Type 2 diabetes mellitus has central complications:Diabetes,a metabolic disorder primarily characterized by hyperglycemia due to insufficient insulin secretion,or impaired insulin signaling,has significant central com... Type 2 diabetes mellitus has central complications:Diabetes,a metabolic disorder primarily characterized by hyperglycemia due to insufficient insulin secretion,or impaired insulin signaling,has significant central complications.Type 2 diabetes mellitus(T2DM),the most prevalent type of diabetes,affects more than 38 million individuals in the United States(approximately 1 in 10)and is defined by chronic hyperglycemia and insulin resistance,which refers to a reduced cellular response to insulin. 展开更多
关键词 reduced cellular response insulin dopamine signaling insulin resistancewhich metabolic disorder type diabetes mellitus brain insulin resistance Alzheimers disease neuropsychiatric symptoms
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Drug sensitivity and drug resistance profiles of human intrahepatic cholangiocarcinoma cell lines 被引量:10
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作者 Nisana Tepsiri Liengchai Chaturat +4 位作者 Banchob Sripa Wises Namwat Sopit Wongkham Vajarabhongsa Bhudhisawasdi Wichittra Tassaneeyakul 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第18期2748-2753,共6页
AIM: To study the effect of a number of chemotherapeutic drugs on five human intrahepatic cholangiocarcinoma (CCA) cell lines. The expressions of genes that have been proposed to influence the resistance of chemothera... AIM: To study the effect of a number of chemotherapeutic drugs on five human intrahepatic cholangiocarcinoma (CCA) cell lines. The expressions of genes that have been proposed to influence the resistance of chemotherapeutic drugs including thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), glutathione-S-transferase PI (GSTP1), multidrug resistance protein (MDR1) and multidrug resistance-associated proteins (MRPs) were also determined. METHODS: Five human CCA cell lines (KKU-100, KKU-M055, KKU-M156, KKU-M214 and KKU-OCA17) were treated with various chemotherapeutic drugs and growth inhibition was determined by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. Semi-quantitative levels of gene expression were determined by a reverse transcriptase polymerase chain reaction (RT-PCR). Results of IC_(50) values and the ratios of gene expression were analyzed by linear regression to predict their relationship. RESULTS: Among five CCA cell lines, KKU-M055 was the most sensitive cell line towards all chemotherapeutic drugs investigated, particularly taxane derivatives with IC_(50) values of 0.02-3 nmol/L, whereas KKU-100 was apparently the least sensitive cell line. When compared to other chemotherapeutic agents, doxorubicin and pirarubicin showed the lowest IC_(50) values (<5 μmol/L) in all five CCA cell lines. Results from RT-PCR showed that TS, MRP1, MRP3 and GSTP1 were highly expressed in these five CCA cell lines while DPD and MRP2 were only moderately expressed. It should be noted that MDR1 expression was detected only in KKU-OCA17 cell lines. A strong correlation was only found between the level of MRP3 expression and the IC_(50) values of etoposide, doxorubicin and pirarubicin (r=0.86-0.98, P<0.05). CONCLUSION: Sensitivity to chemotherapeutic agents is not associated with the histological type of CCA. Choosing of the appropriate chemotherapeutic regimen for the treatment of CCA requires knowledge of drug sensitivity. MRP3 was correlated with resistance of CCA cell lines to etoposide, doxorubicin and pirarubicin, whereas other chemotherapeutic drugs showed no association. The role of this multidrug resistance-associated protein, MRP3, in chemotherapeutic resistance in CCA patients needs to be further investigated. 展开更多
关键词 CHOLANGIOCARCINOMA Chemotherapeutic agents Drug sensitivity Drug resistance Multidrug resistance protein MRP
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Sensitivity Detection Technique and Resistance Risk Assessment of Magnaporthe grisea to Tricyclazole 被引量:2
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作者 ZHANGChuan-qing ZHOUMin_g-guo XUENa 《Rice science》 SCIE 2005年第1期68-74,共7页
In vitro detection method for the sensitivity of Magnaporthe grisea to tricyclazole was studied, and the potential resistance risk of blast disease to tricyclazole was assessed. Both EC50 of hyphal melanization (EC50-... In vitro detection method for the sensitivity of Magnaporthe grisea to tricyclazole was studied, and the potential resistance risk of blast disease to tricyclazole was assessed. Both EC50 of hyphal melanization (EC50-H) and minimum inhibitive concentration of melanization in appressorial (MIC-A) by inhibitor tricyclazole showed positive correlation to the EC50 of tricyclazole against blast disease tested in vivo, with relative co-efficiency (R5) of 0.8995 and 0.8244, respectively. However, stability and reproducibility of EC50-H were better than those of MIC-A, suggesting that it could be used to detect the sensitivity of M. grisea to tricyclazole in vitro. Tricyclazole sensitivity of the progenies derived from single spores of the most sensitive isolate DY2 and the least sensitive isolate GY6 detected in sensitivity monitoring in 2000 was not stable, with mean EC50 values of 4.4968 μg/mL and 5.4010 ug/mL, respectively, indicating that the difference in EC50 between DY2 and GY6 was not caused probably by resistance variation. EC50 of GY6 did not increase significantly when continuously selected for twenty generations under the selection pressure of tricyclazole in vivo. However, the sensitivity of DY2 was decreased by 10-fold after selected for twenty generations. The results suggested that tricyclazole was still low resistance risk for M. grisea in China. 展开更多
关键词 Magnaporthe grisea TRICYCLAZOLE melanin biosynthesis sensitivity detection resistance risk assessment
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Biological Features of KLC2 Mutations in Chronic Myeloid Leukemia and Their Contribution to Inducing Drug Resistance
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作者 Rabindranath Bera Yotaro Ochi +4 位作者 Ying-Jung Huang Ming-Chung Kuo Kenichi Yoshida Seishi Ogawa Lee-Yung Shih 《Oncology Research》 2026年第1期202-221,共20页
Background:Breakpoint Cluster Region-Abelson(BCR::ABL1)fusion protein is essential in the pathogenesis of chronic myeloid leukemia(CML);however,the chronic-to-blast phase transformation remains elusive.We identified n... Background:Breakpoint Cluster Region-Abelson(BCR::ABL1)fusion protein is essential in the pathogenesis of chronic myeloid leukemia(CML);however,the chronic-to-blast phase transformation remains elusive.We identified novel kinesin light chain 2(KLC2)mutations in CML-myeloid blast phase patients.We aimed to examine the functional role of KLC2 mutations in leukemogenesis.Methods:To evaluate the biological role of KLC2 mutants(MT)in CML cells,we expressed KLC2-MT in different human CML cell lines harboring BCR::ABL1 and performed immunoblot,immunofluorescence,cell proliferation,differentiation,and apoptosis;Tyrosine kinase inhibitor(TKI)-drug activities;and clonogenic assays for in vitro functional analyses.We co-expressed KLC2-MT and BCR::ABL1 in mouse bone marrow cells(BMCs)to evaluate their clonogenic and self-renewal abilities ex vivo.Furthermore,we examined tumorigenic activity and drug efficacy in the K562 xenograft model.Results:KLC2-MT overexpression in BCR::ABL1-positive K562 and KU812 CML cells promoted cell proliferation and clonogenic potential,decreased imatinib sensitivity,and reduced apoptosis.Serial colony replating assays revealed that KLC2-MT and BCR::ABL1 co-expression enhanced the self-renewal ability of mouse BMCs with immature morphology.In the K562 xenograft model,KLC2-MT enhanced tumorigenic potential and diminished imatinib efficacy.Further studies reported that KLC2-MT augmented signal transducer and activator of transcription 3(STAT3)activation and nuclear accumulation in imatinib-treated CML cells.KLC2-WT and KLC2-MT interacted with mothers against decapentaplegic homolog 2(SMAD2);however,the latter impaired transforming growth factor-beta(TGF-β)–mediated SMAD2/3 activation while enhancing STAT3 phosphorylation.Conclusions:This study demonstrates the biological and functional importance of KLC2 mutation in CML cells,potentially enabling the development of better treatment strategies for CML patients carrying KLC2 mutations and providing enhanced understanding of the disease progression. 展开更多
关键词 Chronic myeloid leukemia(CML) kinesin light chain 2(KLC2) signal transducer and activator of transcription 3(STAT3) drug resistance myeloid blast transformation
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Effects of multidrug resistance, antisense RNA on the chemosensitivity of hepatocellular carcinoma cells 被引量:10
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作者 Bo Li, Tian Ye, Lei Zhao, De-Hua Li, Xing-Hua Gou, Lan-Ying Zhao, Lei Han, Lin Chen, Lu-Nan Yan and Jian-Ping Gong Department of Hepatobiliary Surgery, Second Affiliated Hospital, Chongqing University of Medical Sciences, Chongqing 400010, China Department of Traditional Chinese Surgery, Second Affiliated Hospital, Luzhou Medical College, Luzhou 646000, China Genetic Engineering Laboratory, Chengdu Di’ao Group Co., Ltd., Chengdu 610041, China Department of General Surgery, West China Hospital, Sichuan University, Chengdu 610041, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2006年第4期552-559,共8页
BACKGROUND: Multidrug resistance is a major obstacle in cancer chemotherapy. We examined whether the antisense RNA of multidrug resistance gene 1 (mdr1) could reverse multidrug resistance in the human hepatocellular c... BACKGROUND: Multidrug resistance is a major obstacle in cancer chemotherapy. We examined whether the antisense RNA of multidrug resistance gene 1 (mdr1) could reverse multidrug resistance in the human hepatocellular carcinoma (HCC) cell line SMMC7721/ADM. METHODS: The recombinant adenoviruses pAdEasy- GFP-ASmdr1 product was produced by the adenoviral vector AdEasy system, which can express antisense RNA against the mdr1 gene. Following that, the recombinant adenovirus was transfected into the P-glycoprotein- producing multidrug resistance cell line, SMMC7721/ADM human HCC cells resistant to adriamycin (ADM) and daunorubicin (DNR). In order to investigate the reversal of multidrug resistance phenotype, we measured the expression of mdr1 mRNA by RT-PCR and the production of P-glycoprotein by flow cytometry. The sensitivities for ADM and DNR SMMC7721/ADM cells were examined by [3-(4, 5-dimethylthi-azol-2-yl)-2,5 diphenyl-terazolium bromide] (MTT) analysis. RESULTS: The low-level expression of mdr1 mRNA and P-glycoprotein production were observed in parental sensitive cells SMMC/7721 in addition to the overexpressionof mdr1 mRNA and P-glycoprotein in SMMC7721/ADM cells. The transfection of antisense-RNA into SMMC7721/ ADM cells resulted in decreases of mdr1 mRNA and P-glycoprotein, but increase of drug sensitivities. The sensitivities of transfected SMMC7721/ADM cells to ADM and DNR in IC50 reduced by 31.25% and 62.96% respectively. CONCLUSIONS: Mdr1 antisense RNA can increase the sensitivities of SMMC7721/ADM cells to anticancer drug by decreasing the expression of the mdr1 gene and inhibiting P-glycoprotein expression. This strategy may be applicable to cancer patients with P-glycoportein mediated multidrug resistance. 展开更多
关键词 antisense nucleic acid multiple drug resistance P-GLYCOPROTEIN
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Enhancing sensitivity of microbial fuel cell sensors for low concentration biodegradable organic matter detection:Regulation of substrate concentration,anode area and external resistance 被引量:2
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作者 Yangyang Gao Sha Wang +4 位作者 Fengjun Yin Pin Hu Xingzu Wang Yuan Liu Hong Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第3期227-235,共9页
The relatively low sensitivity is an important reason for restricting the microbial fuel cell(MFC)sensors'application in low concentration biodegradable organic matter(BOM)detection.The startup parameters,includin... The relatively low sensitivity is an important reason for restricting the microbial fuel cell(MFC)sensors'application in low concentration biodegradable organic matter(BOM)detection.The startup parameters,including substrate concentration,anode area and external resistance,were regulated to enhance the sensitivity of MFC sensors.The results demonstrated that both the substrate concentration and anode area were positively correlated with the sensitivity of MFC sensors,and an external resistance of 210Ωwas found to be optimal in terms of sensitivity of MFC sensors.Optimized MFC sensors had lower detection limit(1 mg/L)and higher sensitivity(Slope value of the linear regression curve was 1.02),which effectively overcome the limitation of low concentration BOM detection.The essential reason is that optimized MFC sensors had higher coulombic efficiency,which was beneficial to improve the sensitivity of MFC sensors.The main impact of the substrate concentration and anode area was to regulate the proportion between electrogens and nonelectrogens,biomass and living cells of the anode biofilm.The external resistance mainly affected the morphology structure and the proportion of living cells of the anode.This study demonstrated an effective way to improve the sensitivity of MFC sensors for low concentration BOM detection. 展开更多
关键词 Microbial fuel cell sensor High sensitivity Biodegradable organic matter Substrate concentration Anode area External resistance
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Porous Bone Structure Inspired Biomimetic Flexible Piezoresistive Sensor with High Sensitivity for Motion Monitoring
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作者 Hengyi Yuan Qingfang Zhang +5 位作者 Yi Li Xiaoyu Zhang Da Li Zhihui Qian Lei Ren Luquan Ren 《Journal of Bionic Engineering》 2025年第3期1322-1337,共16页
Flexible piezoresistive sensors based on biomimetic microstructures are prospective for broad application in motion monitoring.However,the design and preparation processes of most biomimetic microstructures in the exi... Flexible piezoresistive sensors based on biomimetic microstructures are prospective for broad application in motion monitoring.However,the design and preparation processes of most biomimetic microstructures in the existing studies are complicated,and there are few studies on pore size control.Herein,the porous structure of human bones was used as a biomimetic prototype,and optimally designed by creating a theoretical equivalent sensor model and a finite element model.Soluble raw materials such as sugar and salt in different particle sizes were pressed into porous templates.Based on the template method,porous structures in different pore sizes were prepared using polydimethylsiloxane(PDMS)polymer as the substrate.On this basis,graphene oxide conductive coating was prepared with the modified Hummers method and then deposited via dip coating onto the substrate.Finally,a PDMS-based porous structure biomimetic flexible piezoresistive sensor was developed.Mechanically,the deformation of the sensor under the same load increased with the pore size rising from 0.3 to 1.5 mm.Electrically,the resistance rang of the sensor was enlarged as the pore size rose.The resistance variation rates of samples with pore sizes of 0.3,1.0,and 1.5 mm at approximately the 200th cycle were 63%,79%,and 81%,respectively;at the 500th cycle,these values were 63%,77%,and 79%;and at the 1000th cycle,they stabilized at 63%,74%,and 76%.These results indicate that the fabricated sensor exhibits high stability and fatigue resistance.At the pressure of 0–25 kPa,the sensitivity rose from 0.0688 to 0.1260 kPa−1,and the performance was enhanced by 83%.After 1,000 cycles of compression testing,the signal output was stable,and no damage was caused to the substrate.Further application tests showed the biomimetic sensor accurately and effectively identified human joint motions and gestures,and has potential application value in human motion monitoring. 展开更多
关键词 Motion monitoring Biomimetic bone porous structure High sensitivity Flexible piezoresistive sensors
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Unidirectionally Sensitive Flexible Resistance Strain Sensor Based on AgNWs/PDMS
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作者 LIU Xinyue SUN Weiming +6 位作者 HE Mengfan FANG Yuan DJOULDE Aristide DLING Wei LIU Mei MENG Lingjun WANG Zhiming 《Journal of Shanghai Jiaotong university(Science)》 2025年第2期209-219,共11页
The fexible strain sensor has found widespread application due to its excellent fexibility,extensibility,and adaptability to various scenarios.This type of sensors face challenges in direction identification owing to ... The fexible strain sensor has found widespread application due to its excellent fexibility,extensibility,and adaptability to various scenarios.This type of sensors face challenges in direction identification owing to strong coupling between the principal strain and transverse resistance.In this study,a silver nanowires(Ag-NWs)/polydimethylsiloxane(PDMS)strain sensor was developed,using a filtration method for preparing the AgNWs film which was then combined with PDMS to create a unidirectional,highly sensitive,fast-responsive,and linear fexible strain sensor.When the grid width is 0.25 mm,the AgNWs/PDMS strain sensor demonstrates an outstanding unidirectional sensitivity,with a strain response solely along the parallel direction of the grid lines(noise ratioα≈8%),and a fast reaction time of roughly 106.99 ms.In the end,this sensor's ability to detect curvature was also demonstrated through LEDs,demonstrating its potential applications in various fields,including automotive,medical,and wearable devices. 展开更多
关键词 fexible strain sensor silver nanowires(AgNWs) polydimethylsiloxane(PDMS) unidirectional sensitivity
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Seismic Liquefaction Resistance Based on Strain Energy Concept Considering Fine Content Value Effect and Performance Parametric Sensitivity Analysis 被引量:1
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作者 Nima Pirhadi Xusheng Wan +3 位作者 Jianguo Lu Jilei Hu Mahmood Ahmad Farzaneh Tahmoorian 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期733-754,共22页
Liquefaction is one of the most destructive phenomena caused by earthquakes,which has been studied in the issues of potential,triggering and hazard analysis.The strain energy approach is a common method to investigate... Liquefaction is one of the most destructive phenomena caused by earthquakes,which has been studied in the issues of potential,triggering and hazard analysis.The strain energy approach is a common method to investigate liquefaction potential.In this study,two Artificial Neural Network(ANN)models were developed to estimate the liquefaction resistance of sandy soil based on the capacity strain energy concept(W)by using laboratory test data.A large database was collected from the literature.One group of the dataset was utilized for validating the process in order to prevent overtraining the presented model.To investigate the complex influence of fine content(FC)on liquefaction resistance,according to previous studies,the second database was arranged by samples with FC of less than 28%and was used to train the second ANN model.Then,two presented ANN models in this study,in addition to four extra available models,were applied to an additional 20 new samples for comparing their results to show the capability and accuracy of the presented models herein.Furthermore,a parametric sensitivity analysis was performed through Monte Carlo Simulation(MCS)to evaluate the effects of parameters and their uncertainties on the liquefaction resistance of soils.According to the results,the developed models provide a higher accuracy prediction performance than the previously publishedmodels.The sensitivity analysis illustrated that the uncertainties of grading parameters significantly affect the liquefaction resistance of soils. 展开更多
关键词 Liquefaction resistance capacity strain energy artificial neural network sensitivity analysis Monte Carlo Simulation
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Inflammatory cytokine-associated cisplatin resistance in non-small cell lung cancer and re-sensitization through interleukin-6 receptor blockade
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作者 Gizem Calibasi-Kocal 《World Journal of Clinical Oncology》 2025年第12期1-5,共5页
Chemoresistance remains a major challenge in non-small cell lung cancer,especially for cisplatin(DDP)-based therapies,which are a mainstay of treatment.In their study,Dai et al investigate how inflammatory cytokines w... Chemoresistance remains a major challenge in non-small cell lung cancer,especially for cisplatin(DDP)-based therapies,which are a mainstay of treatment.In their study,Dai et al investigate how inflammatory cytokines within the tumor microenvironment contribute to DDP resistance.By analyzing tumor samples from 20 non-small cell lung cancer patients and two resistant cell lines(A549/DDP and SK-MES-1/DDP),the authors show that increased levels of interleukin(IL)-6,IL-8,and tumor necrosis factor-αare linked to resistance.Logistic regression identifies IL-6 and IL-8 as key risk factors.Functional experiments using tocilizumab,an IL-6 receptor antagonist,demonstrate a reduction in DDP half maximum inhibitory concentration,higher apoptosis rates,and decreased migration and invasion in resistant cells.Although the study has certain limitations,such as the analysis of only five inflammatory cytokines in a small,non-stratified patient cohort;it demonstrates that targeting the IL-6 cytokine axis may help overcome DDP resistance.Overall,the study highlights the inflammatory component of the tumor microenvironment as a modifiable driver of chemoresistance and provide a rationale for integrating cytokine blockade into platinum-based chemotherapy regimens to enhance therapeutic response. 展开更多
关键词 Non-small cell lung cancer Cisplatin resistance CYTOKINES INTERLEUKIN-6 Tumor microenvironment
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Use of arrays to investigate the contribution of ATP-binding cassette transporters to drug resistance in cancer chemotherapy and prediction of chemosensitivity 被引量:7
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作者 Jian-Ting Zhang 《Cell Research》 SCIE CAS CSCD 2007年第4期311-323,共13页
Multidrug resistance (MDR) is a major problem in cancer chemotherapy. One of the best known mechanisms of MDR is the elevated expression of ATP-binding cassette (ABC) transporters. While some members of human ABC ... Multidrug resistance (MDR) is a major problem in cancer chemotherapy. One of the best known mechanisms of MDR is the elevated expression of ATP-binding cassette (ABC) transporters. While some members of human ABC transporters have been shown to cause drug resistance with elevated expression, it is not yet known whether the over-expression of other members could also contribute to drug resistance in many model cancer cell lines and clinics. The recent development ofmicroarrays and quantitative PCR arrays for expression profiling analysis of ABC transporters has helped address these issues. In this article, various arrays with limited or full list of ABC transporter genes and their use in identifying ABC transporter genes in drug resistance and chemo-sensitivity prediction will be reviewed. 展开更多
关键词 GENOMICS MDR drug resistance ABC transporter MICROARRAY real time quantitative PCR
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