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重组体pET-28a-alkB/E.coli降解页岩油泥石油烃的功能研究
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作者 李雪菲 句泽林 +3 位作者 齐婷婷 郑乾璐 李喜梅 余丽芸 《山东化工》 CAS 2024年第19期239-243,共5页
为了降解页岩油泥中的石油烃,构建基因工程菌,表达石油烃降解关键酶以提高油泥的降解效果。以Pseudomonas qingdaonensis基因组为模板扩增alkB基因,连接至载体pET-28a,转化至E.coli BL21(DE3)中,SDS-PAGE和Western-blot鉴定表达的外源... 为了降解页岩油泥中的石油烃,构建基因工程菌,表达石油烃降解关键酶以提高油泥的降解效果。以Pseudomonas qingdaonensis基因组为模板扩增alkB基因,连接至载体pET-28a,转化至E.coli BL21(DE3)中,SDS-PAGE和Western-blot鉴定表达的外源蛋白。pET-28a-alkB/E.coli处理原油和页岩油泥,采用气相色谱法评估降解效果。发现alkB基因在大肠杆菌中能表达外源蛋白,且14 d原油及页岩油泥的降解率分别为47.5%和47.1%,表明重组体pET-28a-alkB/E.coli具备降解页岩油泥石油烃的功能。 展开更多
关键词 烷烃单加氧酶alkB 生物降解 e.coli BL21(DE3) 页岩油污泥 气相色谱法
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Exploring the modulatory role of bovine lactoferrin on the microbiome and the immune response in healthy and Shiga toxin‑producing E.coli challenged weaned piglets
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作者 Matthias Dierick Ruben Ongena +2 位作者 Daisy Vanrompay Bert Devriendt Eric Cox 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1278-1291,共14页
Background Post-weaned piglets suffer from F18+Escherichia coli(E.coli)infections resulting in post-weaning diar-rhoea or oedema disease.Frequently used management strategies,including colistin and zinc oxide,have con... Background Post-weaned piglets suffer from F18+Escherichia coli(E.coli)infections resulting in post-weaning diar-rhoea or oedema disease.Frequently used management strategies,including colistin and zinc oxide,have contrib-uted to the emergence and spread of antimicrobial resistance.Novel antimicrobials capable of directly interacting with pathogens and modulating the host immune responses are being investigated.Lactoferrin has shown promising results against porcine enterotoxigenic E.coli strains,both in vitro and in vivo.Results We investigated the influence of bovine lactoferrin(bLF)on the microbiome of healthy and infected weaned piglets.Additionally,we assessed whether bLF influenced the immune responses upon Shiga toxin-producing E.coli(STEC)infection.Therefore,2 in vivo trials were conducted:a microbiome trial and a challenge infection trial,using an F18+STEC strain.BLF did not affect theα-andβ-diversity.However,bLF groups showed a higher relative abundance(RA)for the Actinobacteria phylum and the Bifidobacterium genus in the ileal mucosa.When analysing the immune response upon infection,the STEC group exhibited a significant increase in F18-specific IgG serum levels,whereas this response was absent in the bLF group.Conclusion Taken together,the oral administration of bLF did not have a notable impact on theα-andβ-diversity of the gut microbiome in weaned piglets.Nevertheless,it did increase the RA of the Actinobacteria phylum and Bifi-dobacterium genus,which have previously been shown to play an important role in maintaining gut homeostasis.Furthermore,bLF administration during STEC infection resulted in the absence of F18-specific serum IgG responses. 展开更多
关键词 e.coli Immune modulation LACTOFERRIN MICROBIOME
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Impact of an oligosaccharide-based polymer on the metabolic profiles and microbial ecology of weanling pigs experimentally infected with a pathogenic E.coli
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作者 Kwangwook Kim Cynthia Jinno +4 位作者 Xunde Li David Bravo Eric Cox Peng Ji Yanhong Liu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期749-764,共16页
Background Our previous study has reported that supplementation of oligosaccharide-based polymer enhances gut health and disease resistance of pigs infected with enterotoxigenic E.coli(ETEC)F18 in a manner similar to ... Background Our previous study has reported that supplementation of oligosaccharide-based polymer enhances gut health and disease resistance of pigs infected with enterotoxigenic E.coli(ETEC)F18 in a manner similar to carbadox.The objective of this study was to investigate the impacts of oligosaccharide-based polymer or antibiotic on the host metabolic profiles and colon microbiota of weaned pigs experimentally infected with ETEC F18.Results Multivariate analysis highlighted the differences in the metabolic profiles of serum and colon digesta which were predominantly found between pigs supplemented with oligosaccharide-based polymer and antibiotic.The relative abundance of metabolic markers of immune responses and nutrient metabolisms,such as amino acids and carbohydrates,were significantly differentiated between the oligosaccharide-based polymer and antibiotic groups(q<0.2 and fold change>2.0).In addition,pigs in antibiotic had a reduced(P<0.05)relative abundance of Lachnospiraceae and Lactobacillaceae,whereas had greater(P<0.05)Clostridiaceae and Streptococcaceae in the colon digesta on d 11 post-inoculation(PI)compared with d 5 PI.Conclusions The impact of oligosaccharide-based polymer on the metabolic and microbial profiles of pigs is not fully understood,and further exploration is needed.However,current research suggest that various mechanisms are involved in the enhanced disease resistance and performance in ETEC-challenged pigs by supplementing this polymer. 展开更多
关键词 CARBADOX Colon microbiota Enterotoxigenic e.coli F18 Metabolomics Oligosaccharide-based polymer Weaned pigs
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Evaluating the Potential of Nitrofurantoin and Fosfomycin for E.coli UTIs: A Susceptibility Study
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作者 Usama Ahmed Muhammad Zubair +1 位作者 Baqaur Rehman Hafiz Muhammad Sultan 《Journal of Clinical and Nursing Research》 2024年第6期351-358,共8页
This study was designed to find the susceptibility of Nitrofurantoin and Fosfomycin among urinary isolates of Escherichia.coli.Four hundred(400)urine samples were collected for susceptibility of nitrofurantoin and fos... This study was designed to find the susceptibility of Nitrofurantoin and Fosfomycin among urinary isolates of Escherichia.coli.Four hundred(400)urine samples were collected for susceptibility of nitrofurantoin and fosfomycin among urinary isolates of E.coli.All indoor and outdoor patients'urinary samples yielded growth of E.coli.Mid-stream urine specimens were inoculated on blood agar and CLED agar and incubated at 35±2°C.Growth was observed,and Escherichia coli was identified by Gram staining,Catalase,Motility test and API 20E(Bio murex)as per standard procedure.Antimicrobial susceptibility testing of isolates for nitrofurantoin and fosfomycin was carried out by the modified Kirby-Bauer disc diffusion method according to CLSI guidelines ATCC 25922.E.coli was used as a quality control strain.A total of 400 samples were tested susceptibility of nitrofurantoin and fosfomycin among urinary isolates of E.coli during this period.A total of 400 samples yielded the growth of E.coli,out of which 178(44.5%)were male and 222(55.5%)were female samples.Among males,18(10%)were tolerant to nitrofurantoin,and 2(1.1%)were tolerant to fosfomycin.Among females,9(4.09%)were susceptible to nitrofurantoin while 6(2.72%)were susceptible to fosfomycin.Among age groups below 45 years old,6(4.76%)were tolerant to nitrofurantoin,and 2(1.58%)were sensitive to fosfomycin.Between 46-66 years old,4(2.81%)were sensitive to nitrofurantoin,and 3(2.11%)were sensitive to fosfomycin.Between 67-90 years old,17(12.87%)were sensitive to nitrofurantoin,and 4(3.03%)were tolerant to fosfomycin.Fosfomycin and nitrofurantoin showed good susceptibility in urinary isolates of E.coli and can be used empirically in our setup. 展开更多
关键词 e.coli FOSFOMYCIN NITROFURANTOIN SUSCEPTIBILITY Urinary isolates
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High-level expression of human calmodulin in E.coli and its effects on cell proliferation 被引量:3
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作者 Li XJ Wu JG +2 位作者 Si JL Guo DW Xu JP 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第4期588-592,共5页
Calmodulin (CaM), widely distributed in almost all eukaryotic cells, is a major intracellular calcium receptor responsible for mediating the Ca2 + signal to a multitude of different enzyme systems and is thought to pl... Calmodulin (CaM), widely distributed in almost all eukaryotic cells, is a major intracellular calcium receptor responsible for mediating the Ca2 + signal to a multitude of different enzyme systems and is thought to play a vital role in the regulation of cell proliferative cycle[1,2]. Recently, many studies showed that CaM is also present in extracellular fluid such as cell culture media and normal body fluid and has been reported to stimulate proliferation in a range of normal and neoplastic cells, apparently acting as an autocrine growth factor[3-11]. In 1988, Crocker et al reported for the first time that addition of extracellular pure pig brain CaM could promote DNA synthesis and cell [7]proliferation in K562 human leukaemic lymphocytes[7].After that, more and more research was done on extracellular CaM and evidences demonstrated that extracellular CaM could also stimulate cell proliferation in normal human umbilical vein endothelial cells[5], keratinocytes[4], suspension-cultured cells of Angelica Dahurica, etc[6]. CaM is a monomeric protein of 148 amino acids that contains four homologous Ca2 + -binding domains. CaM has been highly conserved throughout the evolution. Only 1 out of 148 amino acids of human CaM is different from that of fish CaM. Complementary DNAs encoding rat, eel, chicken, human, and trypanosome CaM have been cloned. 展开更多
关键词 CALMODULIN gene expression biological activity ESCHERICHIA COLI cell proliferation TRIFLUOPERAZINE POLYMERASE chain reaction MONOCLONAL antibodies
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Establishment of Cell Free Conversion System With Biotin-labelled Recombinant PrP^(sen) Expressed in E.coli 被引量:1
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作者 JIN ZHANG JIAN-MEI GAO +7 位作者 FENG LI JUN HAN LAN CHEN BAO-YUN ZHANG XIAO-FAN WAMG WEI ZHOU YONG LIU XIAO-PING DONG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2006年第3期214-218,共5页
Objective To report a protocol using biotin-labelled PrP protein in cell free conversion assay instead of isotope. Methods A hamster PrP protein (HaPrP) was expressed in E. coli and purified with HIS-tag affinity ch... Objective To report a protocol using biotin-labelled PrP protein in cell free conversion assay instead of isotope. Methods A hamster PrP protein (HaPrP) was expressed in E. coli and purified with HIS-tag affinity chromatograph. After being labelled with biotin, HaPrP was mixed with PrP^sen preparation from scrapie strain 263K. Results Protease-resistant bands were detected after four-day incubation. Conclusion The new conversion model provides a reliable, easily handling, and environment-friendly method for studies of prion and transmissible spongiform encephalopathies. 展开更多
关键词 Transmissible spongiform eneephalopathies PRION BIOTIN cell free conversion E. coli
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Recombinant E.coli LLO/OVA Vaccination Effectively Inhibits Murine Melanoma Metastasis to Lung by CD8^+T Cells Immunity 被引量:1
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作者 Man Xu Ming-shen Dai Can Mi 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2009年第1期44-49,共6页
Objective: To construct recombinant E.coli LLO/OVA and investigate its tumor metastatic inhibition effect in B16 OVA melanoma challenged mice. Methods: Recombinant E.coli LLO/OVA was constructed and the expression ... Objective: To construct recombinant E.coli LLO/OVA and investigate its tumor metastatic inhibition effect in B16 OVA melanoma challenged mice. Methods: Recombinant E.coli LLO/OVA was constructed and the expression of listeriolysin O (LLO) and ovalbumin (OVA) of the vaccine was determined by coomassie brilliant blue staining and western blotting, After 3 subcutaneous injections of E.coli LLO/OVA, the percentages of CD3^+CD4^+T, CD4^+CD25^+T, CD3^CD8^+T and OVA257-264 SIINFEKL specific CD8^+T cells were determined by flow cytomytry, and the tumor metastatic inhibition effect in B16 OVA melanoma challenged mice was observed. Results: Recombinant E.coli LLO/OVA was successfully constructed, and the expression of LLO and OVA of the vaccine was confirmed. After 3 subcutaneous injections of E.coli LLO/OVA and E.coli OVA in mice, the percentages of CD3^+CD4^+T, CD4^+CD25^+T and CD3^+CD8^+T cells were equivalent in the two groups of mice. However, there were significantly more OVA257-264 SIINFEKL specific CD8^+T cells in E.coli LLO/OVA vaccinated mice than that in E.coli OVA vaccinated mice. The prophylactic E.coli LLO/OVA vaccination effectively prevented the tumor metastasis to lungs in B16 OVA melanoma challenged mice. Depletion of CD8^+T cells significantly impaired the tumor inhibition effect of the vaccine in B16 OVA challenged mice. The therapeutic vaccination of E.coli LLO/OVA significantly prevented melanoma metastasis to lungs in B I6 OVA challenged mice too. Conclusion: Recombinant E.coli LLO/OVA vaccination is highly effective in inhibiting murine malignant melanoma metastasis by promoting CD8^+T cell immunity. 展开更多
关键词 Recombinant e.coli Tumor immunity Cytotoxic T cells METASTASIS
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Recombinant E.coli LLO/OVA Induces Murine BMDCs Maturation via TLR4 and NOD1 Receptor and Promotes Specific Cytotoxic T Cell Immunity
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作者 MAN XU MING-SHEN DAI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2010年第5期350-356,共7页
Objective To explore the immune stimulation effect of recombinant E.coli LLO/OVA on mice bone marrow-derived dendritic cells (BMDCs) and T lymphocytes in vitro.Methods After BMDCs stimulated by E.coli LLO/OVA,their ... Objective To explore the immune stimulation effect of recombinant E.coli LLO/OVA on mice bone marrow-derived dendritic cells (BMDCs) and T lymphocytes in vitro.Methods After BMDCs stimulated by E.coli LLO/OVA,their Toll-like receptor (TLR) and nucleotide-binding oligomerization domain (NOD) receptor signalling pathway were examined by superarray hybridization;and the priming effect of the vaccine activated BMDCs on CD4+T and CD8+T was determined by [3H]thymidine uptake and ELISA,the tumor cytotoxic effect of activated CD8+T cells was determined by cytotoxic assay.Results After BMDCs were activated by E.coli LLO/OVA via TLR4,NOD1 receptor and NF-κB signalling pathway,the expression of their surface molecules including MHC class Ⅰ,MHC class Ⅱ,CD40,CD80 and CD86 significantly up-regulated;the secretion of IL-12 and IFN-? increased also.The mature BMDCs stimulated the allergic CD4+T and CD8+T cells proliferation and their IL-2 and IFN-γ secretion,and the activated CD8+T cells effectively killed B16-OVA melanoma cells and RMA-S/OVA lymphoma cells in vitro.Conclusion E.coli LLO/OVA is effective in inducing BMDCs maturation via activating TLR4 and NOD1 receptor signalling pathway and promoting specific anti-tumor T cell immunity in vitro. 展开更多
关键词 Bone marrow-derived dendritic cells BMDCs Recombinant Escherichia coli Toll-like receptor (TLR) Nucleotide-binding oligomerization domain (NOD) CD8+T cells
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Roles of Optineurin and Extracellular Vesicles in Glaucomatous Retinal Cell Loss 被引量:2
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作者 Chao-ye DUAN Wan-lin FAN Fei CHEN 《Current Medical Science》 SCIE CAS 2023年第2期367-375,共9页
Objective To explore the role of extracellular vesicles(EVs)in the pathogenesis of glaucoma caused by E50K mutation.Methods A photoreceptor cell line,RGC-5,was transfected with empty plasmids and plasmids expressing w... Objective To explore the role of extracellular vesicles(EVs)in the pathogenesis of glaucoma caused by E50K mutation.Methods A photoreceptor cell line,RGC-5,was transfected with empty plasmids and plasmids expressing wild-type(WT)optineurin(OPTN)or E50K OPTN to investigate the effects of OPTN glaucoma as well as to identify the role of EVs in glaucoma pathology.The RGC-5 cells were also stimulated with glutamate,and their viability was evaluated using flow cytometry or CCK-8 assay.EVs were extracted,labeled with PKH-26,and added into the medium for normal RGC-5 culture,and the status of the cells was observed thereafter.Results WT OPTN overexpression,E50K OPTN,and glutamate stimulation induced apoptosis of RGC-5 cells.However,when glutamate stimulation was used as an add-on treatment,the degree of apoptosis in WT OPTN-overexpressing RGC-5 cells was significantly lower than that in E50K OPTN-expressing and normal RGC-5 cells.The viability of normal RGC-5 cells was reduced when co-cultured with WT OPTN-overexpressing RGC-5 or E50K OPTN-overexpressing RGC-5.EVs released by the latter two transfected lines similarly reduced normal RGC-5 survival.Conclusion Our results indicate that WT OPTN overexpression may lead to photoreceptor apoptosis.However,overexpression also confers a degree of protection against high concentrations of extracellular glutamate.Additionally,EVs released by transfected RGC-5 cells may regulate the cell state.These findings may improve our understanding of the mechanisms of cell-cell interactions in pathological conditions,providing a basis for the use of EVs as novel targets for early diagnosis and treatment of glaucoma. 展开更多
关键词 E50K mutation extracellular vesicles GLAUCOMA OPTINEURIN RGC-5 photoreceptor cell line
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Photocatalytic Degradation of E.coli Membrane Cell in the Presence of ZnO Nanowires
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作者 王雪飞 刘鹏 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第2期223-226,共4页
The photocatalytic degradation of E.coli membrane cell by ZnO nanowires was studied using field-emission scanning electron microscope(FE-SEM),fluorescence microscopy,and Attenuated total reflection fourier transform... The photocatalytic degradation of E.coli membrane cell by ZnO nanowires was studied using field-emission scanning electron microscope(FE-SEM),fluorescence microscopy,and Attenuated total reflection fourier transform infrared(ATR-FTIR).The outer membrane of E.coli was removed completely in the presence of ZnO nanowires under UV irradiation,and the cells became twisted shapes without a mechanically strong network.After ZnO nanowires photocatalysis,the permeability of the treated cells increased to some degree that could be confirmed by quantum dots labeling technique.Structural changes in the cell wall membrane were revealed by the decay of the characteristic groups bands in ATR-FTIR spectra. 展开更多
关键词 PHOTOCATALYSIS e.coli ZnO NANOWIRE PERMEABILITY
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Differential expression of bcl-2 and bax genes during the E.coli-induced apoptosis of human U937 cells 被引量:1
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作者 JIA HE WANG YI JUN ZHOU +2 位作者 NA MA LI MIN ZHENG BAI YI CHEN 《Journal of Microbiology and Immunology》 2005年第4期270-273,共4页
To explore the role of bcl-2 and bax genes in the apoptosis of human U937 cells induced by E.coli, flow cytometry assay with annexinⅤ-FITC/PI double staining was used to determine the condition of apoptosis, and the ... To explore the role of bcl-2 and bax genes in the apoptosis of human U937 cells induced by E.coli, flow cytometry assay with annexinⅤ-FITC/PI double staining was used to determine the condition of apoptosis, and the expressions of mRNA of bcl-2 and bax genes were assayed with RT-PCR. It was found that the apoptosis of human U937 cells could be induced by E.coli at various concentration ratios between cells and bacteria for 30 min in a dose-dependent manner. The apoptotic rates at cell/bacteria ratios of 0, 1∶5, 1∶10, 1∶20, 1∶50 and 1∶100 were 3.16%±0.90%, 9.46%±0.84%, 17.90%±1.41%, 35.59%±3.76%, 38.35%±7.12% and 55.07%±5.82% respectively. Also, there was a tendency of alterations in the expression levels of bcl-2 and bax genes with an increased expression level of bax gene and a reduced expression level of bcl-2 gene. It is concluded that E.coli can induce apoptosis in human U937 cells with a down-regulated expression of Bcl-2 and an up-regulated expression of Bax, and this might be related to the induction of apoptosis of the infected cell. 展开更多
关键词 Apoptosis e.coli U937 bcl- 2 bax
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撒坝猪源E.coli高致病性毒力岛通过NLRP3/ASC/Caspase-1途径诱导IPEC-J2细胞焦亡 被引量:1
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作者 肖金龙 王浩 +8 位作者 万全 沈珏 张博 赵维薇 邓静 王喜 赵汝 肖鹏 高洪 《畜牧兽医学报》 CAS CSCD 北大核心 2023年第12期5218-5227,共10页
旨在研究撒坝猪源E.coli高致病性毒力岛(highly pathogenic virulence island,HPI)诱导IPEC-J2细胞焦亡的机制,本研究以LPS+ATP为阳性对照,将实验室前期筛选的E.coli HPI及通过CRISPR/Cas9基因敲除技术构建完成的E.coliΔHPI感染IPEC-J... 旨在研究撒坝猪源E.coli高致病性毒力岛(highly pathogenic virulence island,HPI)诱导IPEC-J2细胞焦亡的机制,本研究以LPS+ATP为阳性对照,将实验室前期筛选的E.coli HPI及通过CRISPR/Cas9基因敲除技术构建完成的E.coliΔHPI感染IPEC-J2细胞,观察细胞损伤情况;RT-qPCR测定各组作用0.5、3、6、9、12 h后细胞内焦亡通路中关键因子NOD样受体家族热蛋白结构域相关蛋白3(NOD-like receptor thermal protein domain associated protein 3,NLRP3)、凋亡相关斑点样蛋白(apoptosis-associated speck-like protein containing a CARD,ASC)、胱天蛋白酶-1(caspase-1)、消皮素D(gasderminD,GSDMD)及炎性因子白介素-18(IL-18)、白介素-1β(IL-1β)的mRNA转录水平;激光共聚焦观察NLRP3/Caspase-1炎性复合体组装及表达情况;Western blot测定GSDMD及其活化形式GSDMD-N蛋白表达水平,PI染色检测胞膜完整性。结果表明:LPS+ATP处理显著促进细胞焦亡的发生,阴性对照组细胞正常生长、轮廓清晰,E.coli感染组及LPS+ATP组细胞出现变形、脱落、边界模糊等明显细胞病变效应(cytopathic effect,CPE),且HE染色显示,E.coliHPI感染相较于E.coliΔHPI感染对细胞的损伤更严重;E.coli HPI组中的焦亡通路关键因子及炎性因子mRNA水平在3~9 h均显著(P<0.05)或极显著(P<0.01)高于E.coliΔHPI组;NLRP3/Caspase-1炎性复合体在细胞质中发生组装,且E.coli HPI组NLRP3/Caspase-1蛋白荧光强度、GSDMD、GSDMD-N蛋白表达水平及PI染色阳性率均极显著(P<0.01)高于E.coliΔHPI组;E.coli HPI组的CPE、HE染色、焦亡通路关键因子及炎性因子mRNA水平、GSDMD及GSDMD-N蛋白表达量、NLRP3/Caspase-1共定位情况均与LPS+ATP组相似。结果提示,撒坝猪源E.coliHPI通过上调NLRP3/ASC/Caspase-1信号通路中关键因子mRNA水平,诱导NLRP3/Caspase-1炎性复合体的组装,促进焦亡标志蛋白GSDMD及GSDMD-N的表达,并对IPEC-J2细胞膜进行打孔,从而诱导细胞发生焦亡。 展开更多
关键词 大肠杆菌 高致病性毒力岛 焦亡 猪小肠上皮细胞 NLRP3/ASC/Caspase-1通路
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2种氟喹诺酮类抗生素与群体感应抑制剂对E.coli的联合毒性效应
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作者 赵远帆 张瑾 +2 位作者 曾健平 张静 张颖 《生态毒理学报》 CAS CSCD 北大核心 2023年第6期27-38,共12页
抗生素滥用带来严重的细菌耐药性,威胁生态环境和人体健康。群体感应抑制剂(quorum sensing inhibitors,QSIs)作为一种理论上难以引发细菌耐药性的新型潜在抗生素替代品,被建议单独使用或与传统抗生素联合使用。因此,考察抗生素与QSIs... 抗生素滥用带来严重的细菌耐药性,威胁生态环境和人体健康。群体感应抑制剂(quorum sensing inhibitors,QSIs)作为一种理论上难以引发细菌耐药性的新型潜在抗生素替代品,被建议单独使用或与传统抗生素联合使用。因此,考察抗生素与QSIs联合作用效应及其作用机理对其在环境中可能产生的联合暴露风险评估具有重要的参考意义。以应用较广泛的2种氟喹诺酮类药物氧氟沙星(ofloxacin,OFL)、左氧氟沙星(levofloxacin,LEV)和1种新型抗菌剂群体感应抑制剂4-羟基-2,5-二甲基-3(2H)呋喃酮(4-hydroxy-2,5-dimethyl-3(2H)-furanone,HDMF)为研究对象,运用直接均分法和均匀设计射线法分别设计3个二元和1个三元混合物体系,每个体系包含5条具有不同组分浓度比的射线。应用时间毒性微板分析法测定3种药物及其混合物体系对大肠杆菌(Escherichia coli,E.coli)的毒性,应用拟合归零法分析混合物的毒性相互作用及相互作用强度,采用分子间对接技术来探讨可能存在的作用机理。结果表明,HDMF、OFL、LEV对E.coli均具有浓度、时间依赖毒性,以半数效应浓度负对数为毒性指标,3种药物在同一暴露时间毒性顺序:LEV>OFL>HDMF。3种药物的二元混合物体系相互作用类型有拮抗/协同作用,而三元混合物体系的作用类型为协同作用,且作用类型和强度受混合物组分、暴露时间和浓度影响。氟喹诺酮类药物混合物体系中,因药物竞争结合蛋白点位而呈现出拮抗作用。在氟喹诺酮类药物和QSIs混合体系中,QSIs会破坏细菌的生物膜,使氟喹诺酮类药物更容易接触细菌造成损伤,从而呈现协同作用。但随着暴露时间的延长,氟喹诺酮类药物会对DNA造成损伤进而减少QSIs作用蛋白的产生,呈现出拮抗作用。 展开更多
关键词 氟喹诺酮类抗生素 群体感应抑制剂 e.coli 联合毒性 分子对接
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Prediction of Tumor Microenvironment Characteristics and Treatment Response in Lung Squamous Cell Carcinoma by Pseudogene OR7E47P-related Immune Genes
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作者 Ya-qi ZHAO Hao-han ZHANG +9 位作者 Jie WU Lan LI Jing LI Hao ZHONG Yan JIN Tian-yu LEI Xin-yi ZHAO Bin XU Qi-bin SONG Jie HE 《Current Medical Science》 SCIE CAS 2023年第6期1133-1150,共18页
Objective Pseudogenes are initially regarded as nonfunctional genomic sequences,but some pseudogenes regulate tumor initiation and progression by interacting with other genes to modulate their transcriptional activiti... Objective Pseudogenes are initially regarded as nonfunctional genomic sequences,but some pseudogenes regulate tumor initiation and progression by interacting with other genes to modulate their transcriptional activities.Olfactory receptor family 7 subfamily E member 47 pseudogene(OR7E47P)is expressed broadly in lung tissues and has been identified as a positive regulator in the tumor microenvironment(TME)of lung adenocarcinoma(LUAD).This study aimed to elucidate the correlation between OR7E47P and tumor immunity in lung squamous cell carcinoma(LUSC).Methods Clinical and molecular information from The Cancer Genome Atlas(TCGA)LUSC cohort was used to identify OR7E47P-related immune genes(ORIGs)by weighted gene correlation network analysis(WGCNA).Based on the ORIGs,2 OR7E47P clusters were identified using non-negative matrix factorization(NMF)clustering,and the stability of the clustering was tested by an extreme gradient boosting classifier(XGBoost).LASSO-Cox and stepwise regressions were applied to further select prognostic ORIGs and to construct a predictive model(ORPScore)for immunotherapy.The Botling cohorts and 8 immunotherapy cohorts(the Samstein,Braun,Jung,Gide,IMvigor210,Lauss,Van Allen,and Cho cohorts)were included as independent validation cohorts.Results OR7E47P expression was positively correlated with immune cell infiltration and enrichment of immune-related pathways in LUSC.A total of 57 ORIGs were identified to classify the patients into 2 OR7E47P clusters(Cluster 1 and Cluster 2)with distinct immune,mutation,and stromal programs.Compared to Cluster 1,Cluster 2 had more infiltration by immune and stromal cells,lower mutation rates of driver genes,and higher expression of immune-related proteins.The clustering performed well in the internal and 5 external validation cohorts.Based on the 7 ORIGs(HOPX,STX2,WFS,DUSP22,SLFN13,GGCT,and CCSER2),the ORPScore was constructed to predict the prognosis and the treatment response.In addition,the ORPScore was a better prognostic factor and correlated positively with the immunotherapeutic response in cancer patients.The area under the curve values ranged from 0.584 to 0.805 in the 6 independent immunotherapy cohorts.Conclusion Our study suggests a significant correlation between OR7E47P and TME modulation in LUSC.ORIGs can be applied to molecularly stratify patients,and the ORPScore may serve as a biomarker for clinical decision-making regarding individualized prognostication and immunotherapy. 展开更多
关键词 PSEUDOGENE olfactory receptor family 7 subfamily E member 47 pseudogene-related immune gene tumor microenvironment IMMUNOTHERAPY lung squamous cell carcinoma
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基于RNA-seq鉴定金黄色葡萄球菌和大肠杆菌型乳房炎的关键应答基因
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作者 师志海 王文佳 +1 位作者 刘洁 王亚州 《家畜生态学报》 北大核心 2024年第7期50-58,共9页
该研究旨在通过转录组测序技术发掘金黄色葡萄球菌和大肠杆菌型奶牛乳房炎相关的关键应答基因,为发掘乳房炎防治有关的生物标志物奠定基础。于体外采用金黄色葡萄球菌处理MAC-T建立了金黄色葡萄球菌乳房炎细胞模型,并进行了转录组测序... 该研究旨在通过转录组测序技术发掘金黄色葡萄球菌和大肠杆菌型奶牛乳房炎相关的关键应答基因,为发掘乳房炎防治有关的生物标志物奠定基础。于体外采用金黄色葡萄球菌处理MAC-T建立了金黄色葡萄球菌乳房炎细胞模型,并进行了转录组测序。同时从公共数据库中收集了9份金黄色葡萄球菌和大肠杆菌处理的乳腺上皮细胞转录组测序样本,结合生物信息分析技术进行了金黄色葡萄球菌和大肠杆菌型乳房炎关键应答基因的发掘。结果发现,乳腺上皮细胞中与金黄色葡萄球菌处理显著关联的差异表达基因有449个,其中上调差异基因有223个,下调差异基因有226个;另有347个差异表达基因与大肠杆菌处理显著关联,其中上调的差异表达基因116个,下调的差异表达基因有231个。功能富集分析发现,金黄色葡萄球菌和大肠杆菌型乳腺上皮细胞中的差异表达基因主要富集到IL-17信号通路。蛋白质互作分析发现,383个金黄色葡萄球菌型乳房炎特异性差异表达基因形成了21个调控网络,其中最大的调控网络包含了67个差异表达基因。另外,281个大肠杆菌乳房炎特异性差异表达基因形成了16个调控网络,其中最大的调控网络包含了33个差异表达基因。利用Cytoscap插件CytoHubba进一步筛选出金黄色葡萄球菌和大肠杆菌型乳房炎的关键应答基因各10个。这些关键应答基因的发掘将为进一步阐明金黄色葡萄球菌和大肠杆菌型乳腺炎的发生发展作用机制奠定基础。 展开更多
关键词 奶牛乳房炎 金黄色葡萄球菌 大肠杆菌 牛乳腺上皮细胞
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益胃解毒方治疗慢性萎缩性胃炎的效果及对Cyclin E、Th17/Treg比值的影响分析
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作者 王立业 张艳彬 +4 位作者 朱亚楠 常玉娟 李晶 柳康康 朱玉光 《检验医学与临床》 CAS 2024年第18期2728-2732,共5页
目的分析益胃解毒方治疗慢性萎缩性胃炎中的效果及对细胞周期蛋白E(Cyclin E)水平、辅助性T细胞(Th17)/调节性T细胞(Treg)比值的影响。方法选取2019年6月至2022年6月在河北省石家庄市中医院确诊的150例慢性萎缩性胃炎患者作为研究对象,... 目的分析益胃解毒方治疗慢性萎缩性胃炎中的效果及对细胞周期蛋白E(Cyclin E)水平、辅助性T细胞(Th17)/调节性T细胞(Treg)比值的影响。方法选取2019年6月至2022年6月在河北省石家庄市中医院确诊的150例慢性萎缩性胃炎患者作为研究对象,按照随机数字表法分为益胃解毒方组、六君子汤组、益胃解毒方+六君子汤组,每组50例。益胃解毒方组使用益胃解毒方治疗,六君子汤组使用六君子汤治疗,益胃解毒方+六君子汤组使用益胃解毒方联合六君子汤治疗,均连续治疗24周。比较3组治疗效果、中医证候积分、Cyclin E水平、Th17/Treg比值、不良反应发生情况。结果益胃解毒方组治疗总有效率高于六君子汤组和益胃解毒方+六君子汤组,且益胃解毒方+六君子汤组高于六君子汤组,差异均有统计学意义(P<0.05)。治疗后3组各项中医证候积分低于治疗前,差异均有统计学意义(P<0.05)。治疗后益胃解毒方组各项中医证候积分低于六君子汤组和益胃解毒方+六君子汤组,且益胃解毒方+六君子汤组低于六君子汤组,差异均有统计学意义(P<0.05)。治疗后3组Cyclin E水平、Th17/Treg比值均低于治疗前,差异均有统计学意义(P<0.05)。治疗后益胃解毒方组Cyclin E水平、Th17/Treg比值低于六君子汤组和益胃解毒方+六君子汤组,且益胃解毒方+六君子汤组低于六君子汤组,差异均有统计学意义(P<0.05)。益胃解毒方组总不良反应发生率低于六君子汤组和益胃解毒方+六君子汤组,且益胃解毒方+六君子汤组低于六君子汤组,差异均有统计学意义(P<0.05)。结论益胃解毒方治疗慢性萎缩性胃炎效果显著,不仅能够改善患者临床症状,调节Cyclin E、Th17/Treg表达,还能减少不良反应发生,值得临床推广应用。 展开更多
关键词 胃癌前病变 益胃解毒方 细胞周期蛋白E 辅助性T细胞 调节性T细胞
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肾移植术后尿路感染209例的临床特点及危险因素分析
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作者 王培宇 丁汉东 +2 位作者 钟金彪 廖贵益 梁朝朝 《器官移植》 CAS CSCD 北大核心 2024年第4期614-621,共8页
目的探讨肾移植术后不同时期尿路感染的特点及其相关危险因素。方法回顾性分析209例肾移植受者的临床资料,按照术后随访时间分为3个时期,第一时期为移植术后1个月内,第二时期为术后1~6个月,第三时期为术后7~12个月。分析肾移植术后不同... 目的探讨肾移植术后不同时期尿路感染的特点及其相关危险因素。方法回顾性分析209例肾移植受者的临床资料,按照术后随访时间分为3个时期,第一时期为移植术后1个月内,第二时期为术后1~6个月,第三时期为术后7~12个月。分析肾移植术后不同时期尿路感染的发生情况,发生尿路感染受者的尿培养结果及常见病原菌耐药特点。分析反复尿路感染者的菌群,分析尿路感染的危险因素及尿路感染对移植肾功能的影响。结果第一时期尿路感染率为90.0%,第二时期尿路感染率为49.3%,第三时期尿路感染率为22.5%。第二时期、第三时期亲属活体器官捐献男性受者的尿路感染率低于女性受者(均为P<0.05)。尿培养结果阳性60例,共检出病原菌84株,以革兰阴性菌为主,其中肺炎克雷伯菌占比最高。66例受者反复发生尿路感染,检出病原菌包括肺炎克雷伯菌、大肠埃希菌、光滑假丝酵母菌和其他。单因素分析结果显示,术后使用抗胸腺细胞球蛋白是第一时期发生尿路感染的危险因素,术前尿路感染、供者类型是第二时期发生尿路感染组的危险因素,受者性别、年龄是第三时期发生尿路感染的危险因素;多因素分析结果显示,术后使用抗胸腺细胞球蛋白是第一时期发生尿路感染的危险因素,受者性别、年龄是第三时期发生尿路感染的危险因素(均为P<0.05)。第三时期治愈65例,未治愈38例,治愈患者治疗后血清肌酐及白细胞水平较治疗前下降(均为P<0.05)。结论肾移植受者尿路感染以革兰阴性菌为主,其耐药性较高;术后使用抗胸腺细胞球蛋白、女性和高龄是肾移植受者发生尿路感染的危险因素。 展开更多
关键词 肾移植 尿路感染 革兰阴性菌 肺炎克雷伯菌 大肠埃希菌 抗胸腺细胞球蛋白 血清肌酐 白细胞
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血清ESM-1、E-cad对ACI-LAA溶栓后HT的预测价值
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作者 茹姗 邹婷 +2 位作者 杜磊 韩登峰 马建华 《脑与神经疾病杂志》 CAS 2024年第2期96-99,共4页
目的 探讨血清内皮细胞特异性分子-1 (ESM-1)、E-钙黏连蛋白(E-cad)对大动脉粥样硬化型脑梗死(ACI-LAA)溶栓后出血转化(HT)的预测价值。方法 选取2020年1月至2022年12月新疆医科大学第一附属医院收治的110例ACI-LAA患者,根据是否发生HT... 目的 探讨血清内皮细胞特异性分子-1 (ESM-1)、E-钙黏连蛋白(E-cad)对大动脉粥样硬化型脑梗死(ACI-LAA)溶栓后出血转化(HT)的预测价值。方法 选取2020年1月至2022年12月新疆医科大学第一附属医院收治的110例ACI-LAA患者,根据是否发生HT分为HT组和non-HT组。对比两组基础资料及血清ESM-1、E-cad水平。采用ROC曲线分析ESM-1、E-cad预测ACI-LAA患者发生HT的价值。结果 HT组患者NIHSS评分高于non-HT组,梗死面积大于non-HT组(P <0.05),HT组患者血清ESM-1、E-cad水平也高于non-HT组(P<0.05)。Logistic回归分析显示,梗死面积大、NIHSS评分高、血清ESM-1和E-cad水平升高是ACI-LAA患者发生HT的危险因素(P<0.05)。ESM-1联合E-cad预测ACI-LAA患者发生HT的曲线下面积为0.859,预测灵敏度为84.6%,特异度为72.6%。结论 血清ESM-1和E-cad水平与ACI-LAA患者HT密切相关,可作为早期预测发生HT的参考指标。 展开更多
关键词 动脉粥样硬化 脑梗死 出血转化 内皮细胞特异性分子-1 E-钙黏连蛋白
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栀子苷调节PI3K/AKT/mTOR信号通路在动脉粥样硬化形成过程中对Th17/Treg功能的影响 被引量:1
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作者 吴佳 吴进 +1 位作者 肖凯 凌超 《中西医结合心脑血管病杂志》 2024年第5期817-822,共6页
目的:观察栀子苷对载脂蛋白E缺乏(ApoE^(-/-))小鼠Th17/调节性T(Treg)细胞失衡的影响及其作用机制。方法:将50只纯合子ApoE^(-/-)雌性小鼠随机分为对照组、模型组和栀子苷低剂量组、栀子苷中剂量组、栀子苷高剂量组。对照组小鼠喂养普... 目的:观察栀子苷对载脂蛋白E缺乏(ApoE^(-/-))小鼠Th17/调节性T(Treg)细胞失衡的影响及其作用机制。方法:将50只纯合子ApoE^(-/-)雌性小鼠随机分为对照组、模型组和栀子苷低剂量组、栀子苷中剂量组、栀子苷高剂量组。对照组小鼠喂养普通饲料,模型组和栀子苷组小鼠喂养高脂饲料。从第8周开始,栀子苷各剂量组每日灌胃栀子苷(25、50、100 mg/kg),连续8周。试验结束时,采用油红O染色评估主动脉及其根部动脉粥样硬化(AS)病变面积比。采用定量逆转录聚合酶链式反应(RT-PCR)分析主动脉组织肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-6、IL-17A和IL-10 mRNA表达;采用流式细胞仪分析脾脏中Th17和Treg细胞百分比;蛋白免疫印迹法(Western Blot)检测主动脉组织磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(AKT)/哺乳动物雷帕霉素靶蛋白(mTOR)信号通路相关蛋白表达。结果:油红O染色病变显示,栀子苷中剂量组、栀子苷高剂量组病变百分比低于模型组(P<0.05)。与对照组比较,模型组主动脉TNF-α、IL-6和IL-17A mRNA表达水平升高(P<0.05);栀子苷各剂量组主动脉TNF-α、IL-6和IL-17A mRNA表达水平降低(P<0.05)。与对照组比较,模型组主动脉抗炎细胞因子IL-10 mRNA表达水平降低(P<0.05);栀子苷各剂量组主动脉抗炎细胞因子IL-10 mRNA表达水平升高(P<0.05)。与对照组比较,模型组小鼠脾脏中Th17细胞百分比升高,Treg细胞百分比降低(P<0.05)。栀子苷处理恢复了AS小鼠Th17和Treg细胞的平衡。栀子苷抑制PI3K的表达及AKT和mTOR的磷酸化,MHY1485(mTOR活化剂)减弱了栀子苷对T细胞分化的影响。结论:栀子苷抗AS作用机制可能与抑制PI3K/AKT/mTOR信号引起的Treg细胞增多和Th17细胞减少有关。 展开更多
关键词 动脉粥样硬化 栀子苷 载脂蛋白E缺乏 Th17/调节性T细胞 磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(AKT)/哺乳动物雷帕霉素靶蛋白(mTOR)信号通路 小鼠 实验研究
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黄芩素对人乳腺癌细胞系MDA-MB-231侵袭、迁移、上皮间充质转化的调控作用及其机制
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作者 陈林 梁秋果 +1 位作者 吉杨丹 王恒 《山东医药》 CAS 2024年第6期10-13,共4页
目的观察黄岑素对人乳腺癌细胞系MDA-MB-231的侵袭、迁移及上皮间充质转化(EMT)的调控作用,探讨其可能作用机制。方法取对数生长期MDA-MB-231细胞分为一组、二组、三组及对照组,一组、二组、三组分别加入2.5、5、10μmol/L的黄岑素,对... 目的观察黄岑素对人乳腺癌细胞系MDA-MB-231的侵袭、迁移及上皮间充质转化(EMT)的调控作用,探讨其可能作用机制。方法取对数生长期MDA-MB-231细胞分为一组、二组、三组及对照组,一组、二组、三组分别加入2.5、5、10μmol/L的黄岑素,对照组不做任何处理。培养48 h时采用划痕修复实验观察四组细胞迁移能力、采用Transwell侵袭实验观察四组细胞侵袭能力,采用Western Blotting法检测细胞EMT标志物波形蛋白(vimentin)及E-钙黏蛋白(E-cadherin)、整合素αv、β3、磷酸化黏着斑激酶(p-FAK)、磷酸化磷脂酰肌醇3激酶(整合素p-PI3K)。结果与对照组相比,黄岑素组细胞迁移率降低、侵袭细胞数少,细胞E-cadherin相对表达量高,vimentin、整合素αv、整合素β3、p-FAK、p-PI3K蛋白相对表达量低,且呈剂量依赖性(P均<0.05)。结论黄芩素抑制MDA-MB-231细胞的侵袭、迁移及EMT。黄岑素可能通过抑制整合素αv、整合素β3表达,进一步抑制p-FAK、p-PI3K蛋白表达,抑制MDA-MB-231的侵袭、迁移及EMT。 展开更多
关键词 黄芩素 乳腺癌 细胞侵袭 细胞迁移 上皮间质转化 波形蛋白 E-钙黏蛋白 整合素αv、整合素β3 黏着斑激酶 磷脂酰肌醇3激酶
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