Terahertz metamaterial biosensors have attracted significant attention in the biological field due to their advantages of label-free,real-time and in situ detection.In this paper,a highly sensitive metamaterial sensor...Terahertz metamaterial biosensors have attracted significant attention in the biological field due to their advantages of label-free,real-time and in situ detection.In this paper,a highly sensitive metamaterial sensor with semi-ring mirror symmetry based on toroidal dipole resonance is designed for a new metamaterial biosensor.It is shown that a refractive index sensitivity of 337.5 GHz per refractive index unit can be achieved under an analyte of saturated thickness near a 1.33 THz transmission dip.For biosensor samples where aflatoxin B1 is dropped on the metamaterial surface in our experiment,dip amplitudes of transmission varying from 0.1904 to 0.203 and 0.2093 are observed as aflatoxin B1 concentrations are altered from 0 to 0.001μg·ml-1 and to 0.01μg·ml-1,respectively.Furthermore,when aflatoxin B1 concentrations are 0.1μg·ml-1,1μg·ml-1,10μg·ml-1 and 100μg·ml-1,dip amplitudes of 0.2179,0.226,0.2384 and 0.2527 and dip redshifts of 10.1 GHz,20.1 GHz,27.7 GHz and 37.6 GHz are respectively observed.These results illustrate high-sensitivity,label-free detection of aflatoxin B1,enriching the applications of sensors in the terahertz domain.展开更多
BACKGROUND The dysregulation of tissue inhibitor of metalloproteinase-3(TIMP3)was positively correlated with the progression of hepatocellular carcinoma(HCC).However,it is not clear whether TIMP3 expression is associa...BACKGROUND The dysregulation of tissue inhibitor of metalloproteinase-3(TIMP3)was positively correlated with the progression of hepatocellular carcinoma(HCC).However,it is not clear whether TIMP3 expression is associated with the clinico-pathological features and prognosis of aflatoxin B1(AFB1)-related HCC(AHCC).A retrospective study,including 182 patients with AHCC,was conducted to explore the link between TIMP3 expression in cancerous tissues and the clinico-pathological characteristics and prognosis of AHCC.TIMP3 expression was detected by immunohistochemistry and its effects on the clinicopathological features and prognosis of AHCC were evaluated by Kaplan-Meier survival analysis and Cox regression survival analysis.Odds ratio,hazard ratio(HR),median overall survival time(MST),median tumor recurrence-free survival time(MRT),and corresponding 95%confidential interval(CI)was calculated to RESULTS Kaplan-Meier survival analysis showed that compared with high TIMP3 expression,low TIMP3 expression in tumor tissues significantly decreased the MST(36.00 mo vs 18.00 mo)and MRT(32.00 mo vs 16 mo)of patients with AHCC.Multivariate Cox regression survival analysis further proved that decreased expression of TIMP3 increased the risk of death(HR=2.85,95%CI:2.04-4.00)and tumor recurrence(HR=2.26,95%CI:1.57-3.26).Furthermore,decreased expression of TIMP3 protein in tissues with AHCC was significantly correlated with tumor clinicopatho-logical features,such as tumor size,tumor grade and stage,tumor microvessel density,and tumor blood invasion.Additionally,TIMP3 protein expression was also negatively associated with amount of AFB1-DNA adducts in tumor tissues.CONCLUSION These findings indicate that the dysregulation of TIMP3 expression is related to AHCC biological behaviors and affects tumor outcome,suggesting that TIMP3 may act as a prognostic biomarker for AHCC.展开更多
San-Huang chicken is a high-quality breed in China with yellow feather, claw and break. However, the abnormal phenomenon of the yellow shank turning into green shank of San-Huang chicken has been a concern, as it seri...San-Huang chicken is a high-quality breed in China with yellow feather, claw and break. However, the abnormal phenomenon of the yellow shank turning into green shank of San-Huang chicken has been a concern, as it seriously reduces the carcass quality and economic benefit of yellow-feathered broilers. In this study, the cause of this abnormal green skin in shank was systematically investigated. Physiological anatomy revealed that the abnormal skin in shank was primarily due to the deposition of melanin under the dermis. After analyzing multiple potential causes such as heredity(pedigree and genetic markers), environment(water quality monitoring) and feed composition(mycotoxin detection), excessive aflatoxin B1(AFB1) in feed was screened, accompanied with a higher L-dihydroxy-phenylalanine(L-DOPA)(P<0.05) and melanin content(P<0.01). So it was speculated that excessive AFB1 might be the main cause of abnormal green skin in shank. Subsequently, the further results showed that a high concentration of AFB1(>170 μg kg–1)indeed induced the abnormal green skin in shank compared to the normal AFB1 content(<10 μg kg–1), and the mRNA levels of TYR, TYRP1, MITE, MC1R and EDN3 genes related to melanin deposition would significantly up-regulate(P<0.01) and the content and activity of tyrosinase(TyR) significantly increased(P<0.05). At the same time, the content of L-DOPA and melanin deposition also increased significantly(P<0.01), which also confirmed the effect of excessive AFB1 on melanin deposition in skin of shank. Results of additional experiments revealed that the AFB1's negative effect on melanin deposition in skin of shank could last for a longer time. Taken together, the results of this study explained the occurrence and possible mechanisms of the abnormal AFB1-related green skin in shank of chickens. Excessive AFB1 in diets increased the L-DOPA content and melanin abnormal deposition in the chicken shank possibly via promoting TyR content and activity, and the expression of melanin synthesis-related genes. Furthermore, our findings once again raised the alarm of the danger of AFB1 in the broiler production.展开更多
Purpose: Aflatoxin B<sub>1</sub> is the most common mycotoxin in cereal crops;it is of stronger toxicity and has a carcinogenic effect. In recent years, a series of fluorescence sensors constructed on the ...Purpose: Aflatoxin B<sub>1</sub> is the most common mycotoxin in cereal crops;it is of stronger toxicity and has a carcinogenic effect. In recent years, a series of fluorescence sensors constructed on the basis of MoS<sub>2</sub>NS fluorescence quenching property have become a research hotspot. Therefore, we can construct a fast and simple analysis method with high specificity to detect AFB<sub>1</sub> by utilizing MoS<sub>2</sub>NS, which can be effectively applied to food safety monitoring and clinical diagnosis. Method: In the current research, a fluorescence biosensor is developed on the basis of a new type of two-dimensional nano-material namely MoS<sub>2</sub>NS applied for the detection of AFB<sub>1</sub>. The fluorescence of Apt@AFB<sub>1</sub> can be quickly quenched by MoS<sub>2</sub>NS through the fluorescence resonance energy transfer (FRET). When the target molecule AFB<sub>1</sub> exists, after the specificity binding between AFB<sub>1</sub> and aptamer, the Apt@AFB<sub>1</sub> loses its single stranded structure and is away from MoS<sub>2</sub>NS, and the fluorescence of Apt®AFB<sub>1</sub> cannot be quenched effectively. Such sensing signals can be used to achieve the sensitive detection of AFB<sub>1</sub>. Result: With this new method, under the optimized conditions, the AFB<sub>1</sub> is analyzed in the MoS<sub>2</sub>NS/Apt®AFB<sub>1</sub> sensing platform. Within the dynamic range of 0.2 - 25 ng/mL, the sensing platform expresses a good linear response to the level of AFB<sub>1</sub> with the R<sup>2</sup> = 0.9964 and LOD as 90 pg/mL. This method is applied to detect the actual serum samples and soybean milk with the recovery rate of 93.10% - 107.23% and 95.15% - 102.60% separately, and it can be used in the quantitative detection under the interference of other mycotoxins in a relatively accurate way. Conclusion: It is proved that this new detection method can be used as a potential biosensor platform for the detection of AFB<sub>1</sub>. This detection method features several advantages such as specificity, rapidness and low costs, which can meet the requirement of trace detection in clinical detection and food safety.展开更多
Edible oil is one major nutritional ingredient to human and widely consumed directly. The contamination of aflatoxin B1 （AFB1） in edible oils has been attracted exten-sive efforts due to its hazard to human health a...Edible oil is one major nutritional ingredient to human and widely consumed directly. The contamination of aflatoxin B1 （AFB1） in edible oils has been attracted exten-sive efforts due to its hazard to human health and life. To avoid the digestion of edible oils contaminated by AFB1 the development of rapid and sensitive sensing method for AFB1 is required. Herein, a quantitative, sensitive and rapid method for AFB1 detection in edible oils was proposed by using ultrasensitive time-resolved fluorescent immunosensing （TRFIS） method. This method poses unique advantages from both time-resolved fluorescent sens-ing method and immunochromatographic assay format. The nanospheres were modified with fluorescent europium and then captured the home-made monoclonal antibody against AFB1 （3G1）. After optimization, by using a competitive immunosensing manner, this TRFIS method has a detectable linear range of 0.54-20.0 μg/kg with minimum detectable concen-tration of 0.18μg/kg. It can be completed merely within 10 min with recovery from 87.0% to 121.9%. The agreement was observed between the results by TRFIS and high perfor-mance liquid chromatography （HPLC） methods. This research provides a promising sens-ing method for sensitive and rapid determining AFB1 in edible oils.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61927813,61865009,and 12104203)Jiangxi Provincial Natural Science Foundation(Grant No.20212ACB201007).
文摘Terahertz metamaterial biosensors have attracted significant attention in the biological field due to their advantages of label-free,real-time and in situ detection.In this paper,a highly sensitive metamaterial sensor with semi-ring mirror symmetry based on toroidal dipole resonance is designed for a new metamaterial biosensor.It is shown that a refractive index sensitivity of 337.5 GHz per refractive index unit can be achieved under an analyte of saturated thickness near a 1.33 THz transmission dip.For biosensor samples where aflatoxin B1 is dropped on the metamaterial surface in our experiment,dip amplitudes of transmission varying from 0.1904 to 0.203 and 0.2093 are observed as aflatoxin B1 concentrations are altered from 0 to 0.001μg·ml-1 and to 0.01μg·ml-1,respectively.Furthermore,when aflatoxin B1 concentrations are 0.1μg·ml-1,1μg·ml-1,10μg·ml-1 and 100μg·ml-1,dip amplitudes of 0.2179,0.226,0.2384 and 0.2527 and dip redshifts of 10.1 GHz,20.1 GHz,27.7 GHz and 37.6 GHz are respectively observed.These results illustrate high-sensitivity,label-free detection of aflatoxin B1,enriching the applications of sensors in the terahertz domain.
基金the Science-Technology Planning Project of Guangxi,No.Guike-AD19245174Guangxi Training Program for Medical High-level Academic Leaders,No.6 of Guiweikejiaofa[2020]-15+3 种基金Bose Talent Highland,No.2020-3-2Building Projects from the Key Laboratory of Molecular Pathology(Hepatobiliary Diseases)of Guangxi,No.Guiweikejiaofa[2020]-17the Key Laboratory of Tumor Molecular Pathology of Guangxi Colleges and Universities,No.Guijiaokeyan[2022]-10Clinical Key Specialty Building Project(For Pathology)of Guangxi,No.Guiweiyifa[2022]-21.
文摘BACKGROUND The dysregulation of tissue inhibitor of metalloproteinase-3(TIMP3)was positively correlated with the progression of hepatocellular carcinoma(HCC).However,it is not clear whether TIMP3 expression is associated with the clinico-pathological features and prognosis of aflatoxin B1(AFB1)-related HCC(AHCC).A retrospective study,including 182 patients with AHCC,was conducted to explore the link between TIMP3 expression in cancerous tissues and the clinico-pathological characteristics and prognosis of AHCC.TIMP3 expression was detected by immunohistochemistry and its effects on the clinicopathological features and prognosis of AHCC were evaluated by Kaplan-Meier survival analysis and Cox regression survival analysis.Odds ratio,hazard ratio(HR),median overall survival time(MST),median tumor recurrence-free survival time(MRT),and corresponding 95%confidential interval(CI)was calculated to RESULTS Kaplan-Meier survival analysis showed that compared with high TIMP3 expression,low TIMP3 expression in tumor tissues significantly decreased the MST(36.00 mo vs 18.00 mo)and MRT(32.00 mo vs 16 mo)of patients with AHCC.Multivariate Cox regression survival analysis further proved that decreased expression of TIMP3 increased the risk of death(HR=2.85,95%CI:2.04-4.00)and tumor recurrence(HR=2.26,95%CI:1.57-3.26).Furthermore,decreased expression of TIMP3 protein in tissues with AHCC was significantly correlated with tumor clinicopatho-logical features,such as tumor size,tumor grade and stage,tumor microvessel density,and tumor blood invasion.Additionally,TIMP3 protein expression was also negatively associated with amount of AFB1-DNA adducts in tumor tissues.CONCLUSION These findings indicate that the dysregulation of TIMP3 expression is related to AHCC biological behaviors and affects tumor outcome,suggesting that TIMP3 may act as a prognostic biomarker for AHCC.
基金funded by the grants from the China Agriculture Research System of MOF and MARA (CARS-41)the Agricultural Science and Technology Innovation Program, China (ASTIP-IAS04)。
文摘San-Huang chicken is a high-quality breed in China with yellow feather, claw and break. However, the abnormal phenomenon of the yellow shank turning into green shank of San-Huang chicken has been a concern, as it seriously reduces the carcass quality and economic benefit of yellow-feathered broilers. In this study, the cause of this abnormal green skin in shank was systematically investigated. Physiological anatomy revealed that the abnormal skin in shank was primarily due to the deposition of melanin under the dermis. After analyzing multiple potential causes such as heredity(pedigree and genetic markers), environment(water quality monitoring) and feed composition(mycotoxin detection), excessive aflatoxin B1(AFB1) in feed was screened, accompanied with a higher L-dihydroxy-phenylalanine(L-DOPA)(P<0.05) and melanin content(P<0.01). So it was speculated that excessive AFB1 might be the main cause of abnormal green skin in shank. Subsequently, the further results showed that a high concentration of AFB1(>170 μg kg–1)indeed induced the abnormal green skin in shank compared to the normal AFB1 content(<10 μg kg–1), and the mRNA levels of TYR, TYRP1, MITE, MC1R and EDN3 genes related to melanin deposition would significantly up-regulate(P<0.01) and the content and activity of tyrosinase(TyR) significantly increased(P<0.05). At the same time, the content of L-DOPA and melanin deposition also increased significantly(P<0.01), which also confirmed the effect of excessive AFB1 on melanin deposition in skin of shank. Results of additional experiments revealed that the AFB1's negative effect on melanin deposition in skin of shank could last for a longer time. Taken together, the results of this study explained the occurrence and possible mechanisms of the abnormal AFB1-related green skin in shank of chickens. Excessive AFB1 in diets increased the L-DOPA content and melanin abnormal deposition in the chicken shank possibly via promoting TyR content and activity, and the expression of melanin synthesis-related genes. Furthermore, our findings once again raised the alarm of the danger of AFB1 in the broiler production.
文摘Purpose: Aflatoxin B<sub>1</sub> is the most common mycotoxin in cereal crops;it is of stronger toxicity and has a carcinogenic effect. In recent years, a series of fluorescence sensors constructed on the basis of MoS<sub>2</sub>NS fluorescence quenching property have become a research hotspot. Therefore, we can construct a fast and simple analysis method with high specificity to detect AFB<sub>1</sub> by utilizing MoS<sub>2</sub>NS, which can be effectively applied to food safety monitoring and clinical diagnosis. Method: In the current research, a fluorescence biosensor is developed on the basis of a new type of two-dimensional nano-material namely MoS<sub>2</sub>NS applied for the detection of AFB<sub>1</sub>. The fluorescence of Apt@AFB<sub>1</sub> can be quickly quenched by MoS<sub>2</sub>NS through the fluorescence resonance energy transfer (FRET). When the target molecule AFB<sub>1</sub> exists, after the specificity binding between AFB<sub>1</sub> and aptamer, the Apt@AFB<sub>1</sub> loses its single stranded structure and is away from MoS<sub>2</sub>NS, and the fluorescence of Apt®AFB<sub>1</sub> cannot be quenched effectively. Such sensing signals can be used to achieve the sensitive detection of AFB<sub>1</sub>. Result: With this new method, under the optimized conditions, the AFB<sub>1</sub> is analyzed in the MoS<sub>2</sub>NS/Apt®AFB<sub>1</sub> sensing platform. Within the dynamic range of 0.2 - 25 ng/mL, the sensing platform expresses a good linear response to the level of AFB<sub>1</sub> with the R<sup>2</sup> = 0.9964 and LOD as 90 pg/mL. This method is applied to detect the actual serum samples and soybean milk with the recovery rate of 93.10% - 107.23% and 95.15% - 102.60% separately, and it can be used in the quantitative detection under the interference of other mycotoxins in a relatively accurate way. Conclusion: It is proved that this new detection method can be used as a potential biosensor platform for the detection of AFB<sub>1</sub>. This detection method features several advantages such as specificity, rapidness and low costs, which can meet the requirement of trace detection in clinical detection and food safety.
基金This work was supported by Special Fund for Grain -scientific Research in the Public Interest （201513006-02）, Special Fund for Agro -scientific Research in the Public Interest （201203094）, Natural Science Foundation of China （31401601）.
文摘Edible oil is one major nutritional ingredient to human and widely consumed directly. The contamination of aflatoxin B1 （AFB1） in edible oils has been attracted exten-sive efforts due to its hazard to human health and life. To avoid the digestion of edible oils contaminated by AFB1 the development of rapid and sensitive sensing method for AFB1 is required. Herein, a quantitative, sensitive and rapid method for AFB1 detection in edible oils was proposed by using ultrasensitive time-resolved fluorescent immunosensing （TRFIS） method. This method poses unique advantages from both time-resolved fluorescent sens-ing method and immunochromatographic assay format. The nanospheres were modified with fluorescent europium and then captured the home-made monoclonal antibody against AFB1 （3G1）. After optimization, by using a competitive immunosensing manner, this TRFIS method has a detectable linear range of 0.54-20.0 μg/kg with minimum detectable concen-tration of 0.18μg/kg. It can be completed merely within 10 min with recovery from 87.0% to 121.9%. The agreement was observed between the results by TRFIS and high perfor-mance liquid chromatography （HPLC） methods. This research provides a promising sens-ing method for sensitive and rapid determining AFB1 in edible oils.
