Aflatoxin B1(AFB1)is a highly toxic mycotoxin,and rapid and sensitive detection of AFB1 is in demand for food safety and environmental analysis.Here we described a simple aptamer molecular beacon assay for rapid detec...Aflatoxin B1(AFB1)is a highly toxic mycotoxin,and rapid and sensitive detection of AFB1 is in demand for food safety and environmental analysis.Here we described a simple aptamer molecular beacon assay for rapid detection of aflatoxin B1(AFB1)by using an aptamer with a fluorescein(FAM)label at the 50 end and a fluorescence quencher(black hole quencher 1,BHQ1)at the 30 end.In the presence of AFB1,the aptamer probe bound with AFB1 and induced a hairpin structure,drawing FAM and BHQ1 into close proximity and leading to fluorescence quenching.This assay allowed for a detection limit of 3.9 nmol/L and a dynamic range from 3.9 nmol/L to 4 mmol/L.Specificity test showed other mycotoxins including ochratoxin A,ochratoxin B,fumonisin B1,fumonisin B2,and zearalenone had negligible influence on detection of AFB1.AFB1 spiked in diluted liquor wine,methanol,or corn flour samples was successfully detected by using this aptamer probe,and the assay showed potential for real sample analysis.展开更多
Tuberculosis is one of the leading infectious diseases plaguing mankind and is mediated by the facultative pathogen, Mycobacterium tuberculosis(MTB). Once the pathogen enters the body, it subverts the host immune defe...Tuberculosis is one of the leading infectious diseases plaguing mankind and is mediated by the facultative pathogen, Mycobacterium tuberculosis(MTB). Once the pathogen enters the body, it subverts the host immune defenses and thrives for extended periods of time within the host macrophages in the lung granulomas, a condition called latent tuberculosis(LTB). Persons with LTB are prone to reactivation of the disease when the body's immunity is compromised. Currently there are no reliable and effective diagnosis and treatment options for LTB, which necessitates new research in this area. The mycobacterial proteins and genes mediating the adaptive responses inside the macrophage is largely yet to be determined. Recently, it has been shown that the mce operon genes are critical for host cell invasion by the mycobacterium and for establishing a persistent infection in both in vitro and in mouse models of tuberculosis. The Yrb E and Mce proteins which are encoded by the MTB mce operons display high degrees of homology to the permeases and the surface binding protein of the ABC transports, respectively. Similarities in structure and cell surface location impute a role in cell invasion at cholesterol rich regions and immunomodulation. The mce4 operon is also thought to encode a cholesterol transport system that enables the mycobacterium to derive both energy and carbon from the host membrane lipids and possibly generating virulence mediating metabolites, thus enabling the bacteria in its long term survival within the granuloma. Various deletion mutation studies involving individual or whole mce operon genes have shown to be conferring varying degrees of attenuation of infectivity or at times hypervirulence to the host MTB, with the deletion of mce4 A operon gene conferring the greatest degree of attenuation of virulence. Antisense technology using synthetic si RNAs has been used in knocking down genes in bacteria and over the years this has evolvedinto a powerful tool for elucidating the roles of various genes mediating i展开更多
目的研究Survivin分子信标检测膀胱尿路上皮癌的临床价值。方法收集280例血尿患者的尿液标本进行Survivin分子信标检测,其中膀胱尿路上皮癌177例,非膀胱尿路上皮癌患者103例。对73例膀胱尿路上皮癌患者的肿瘤组织进行免疫组织化学染色...目的研究Survivin分子信标检测膀胱尿路上皮癌的临床价值。方法收集280例血尿患者的尿液标本进行Survivin分子信标检测,其中膀胱尿路上皮癌177例,非膀胱尿路上皮癌患者103例。对73例膀胱尿路上皮癌患者的肿瘤组织进行免疫组织化学染色。结果 Survivin分子信标检测膀胱尿路上皮癌的灵敏度和特异度分别为81.4%和73.8%,免疫组织化学染色检测Survivin表达的阳性率是90.4%(66 of 73)。Survivin分子信标检测膀胱尿路上皮癌与患者的临床分期密切相关。结论 Survivin分子信标是一种具有较高灵敏度和特异度的检测膀胱尿路上皮癌的非侵入性检查方法,比尿脱落细胞学检查具有更高的灵敏度,有望成为一种检测膀胱尿路上皮癌和膀胱尿路上皮癌术后随访的新的检测手段。展开更多
基金financial support from the National Natural Science Foundation of China(Nos.21575153,21435008,21874146)Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB14030200)the Key Research Program of the Chinese Academy of Sciences(No.KFZD-SW-203)
文摘Aflatoxin B1(AFB1)is a highly toxic mycotoxin,and rapid and sensitive detection of AFB1 is in demand for food safety and environmental analysis.Here we described a simple aptamer molecular beacon assay for rapid detection of aflatoxin B1(AFB1)by using an aptamer with a fluorescein(FAM)label at the 50 end and a fluorescence quencher(black hole quencher 1,BHQ1)at the 30 end.In the presence of AFB1,the aptamer probe bound with AFB1 and induced a hairpin structure,drawing FAM and BHQ1 into close proximity and leading to fluorescence quenching.This assay allowed for a detection limit of 3.9 nmol/L and a dynamic range from 3.9 nmol/L to 4 mmol/L.Specificity test showed other mycotoxins including ochratoxin A,ochratoxin B,fumonisin B1,fumonisin B2,and zearalenone had negligible influence on detection of AFB1.AFB1 spiked in diluted liquor wine,methanol,or corn flour samples was successfully detected by using this aptamer probe,and the assay showed potential for real sample analysis.
文摘Tuberculosis is one of the leading infectious diseases plaguing mankind and is mediated by the facultative pathogen, Mycobacterium tuberculosis(MTB). Once the pathogen enters the body, it subverts the host immune defenses and thrives for extended periods of time within the host macrophages in the lung granulomas, a condition called latent tuberculosis(LTB). Persons with LTB are prone to reactivation of the disease when the body's immunity is compromised. Currently there are no reliable and effective diagnosis and treatment options for LTB, which necessitates new research in this area. The mycobacterial proteins and genes mediating the adaptive responses inside the macrophage is largely yet to be determined. Recently, it has been shown that the mce operon genes are critical for host cell invasion by the mycobacterium and for establishing a persistent infection in both in vitro and in mouse models of tuberculosis. The Yrb E and Mce proteins which are encoded by the MTB mce operons display high degrees of homology to the permeases and the surface binding protein of the ABC transports, respectively. Similarities in structure and cell surface location impute a role in cell invasion at cholesterol rich regions and immunomodulation. The mce4 operon is also thought to encode a cholesterol transport system that enables the mycobacterium to derive both energy and carbon from the host membrane lipids and possibly generating virulence mediating metabolites, thus enabling the bacteria in its long term survival within the granuloma. Various deletion mutation studies involving individual or whole mce operon genes have shown to be conferring varying degrees of attenuation of infectivity or at times hypervirulence to the host MTB, with the deletion of mce4 A operon gene conferring the greatest degree of attenuation of virulence. Antisense technology using synthetic si RNAs has been used in knocking down genes in bacteria and over the years this has evolvedinto a powerful tool for elucidating the roles of various genes mediating i
文摘目的研究Survivin分子信标检测膀胱尿路上皮癌的临床价值。方法收集280例血尿患者的尿液标本进行Survivin分子信标检测,其中膀胱尿路上皮癌177例,非膀胱尿路上皮癌患者103例。对73例膀胱尿路上皮癌患者的肿瘤组织进行免疫组织化学染色。结果 Survivin分子信标检测膀胱尿路上皮癌的灵敏度和特异度分别为81.4%和73.8%,免疫组织化学染色检测Survivin表达的阳性率是90.4%(66 of 73)。Survivin分子信标检测膀胱尿路上皮癌与患者的临床分期密切相关。结论 Survivin分子信标是一种具有较高灵敏度和特异度的检测膀胱尿路上皮癌的非侵入性检查方法,比尿脱落细胞学检查具有更高的灵敏度,有望成为一种检测膀胱尿路上皮癌和膀胱尿路上皮癌术后随访的新的检测手段。
