A total of 133 shellfish samples were collected in seven cities of Shandong Province,China,from May to October,2019.The domoic acid(DA)concentrations were determined by liquid chromatographytandem mass spectrometry(LC...A total of 133 shellfish samples were collected in seven cities of Shandong Province,China,from May to October,2019.The domoic acid(DA)concentrations were determined by liquid chromatographytandem mass spectrometry(LC-MS/MS),and their distribution characteristics were investigated.DA concentration was detected high in over 1/3(36.1%)of the samples of four kinds of shellfish in all three seasons in range from 0 to 102μg/kg.The highest DA concentrations were 102,101,36.7,and 10.2μg/kg in Crassostrea gigas,Chlamys farreri,Mactra veneriformis,and Mytilus edulis,respectively.Geographically,Yantai(22.0μg/kg)and Weihai(16.9μg/kg)showed relatively high concentrations of DA,whereas Rizhao and Dongying presented only 0.85-and 1.76-μg/kg DA,respectively.DA concentrations in the shellfish samples were strongly related to seasonal changes,being significantly higher in autumn and summer than that in spring.The DA risk exposure assessments indicate that dietary seafood consumption did not pose a health threat to general human population.In addition,three isomers(isoA,isoD,isoE)and 5′-epimer DA were detected in 3.00%-15.80%of the shellfish samples.This study is the first to observe DA and its isomers in shellfish samples of Shandong Province.The results demonstrate that DA contamination is very common and should be continuously monitored.展开更多
A simple method for spiking formulated feed with domoic acid (DA) was developed in this study. DA feed was prepared by mixing 0.15 mL 100 μg mL-1 DA with 0.1 g formulated feed, and drying the mixture at room temperat...A simple method for spiking formulated feed with domoic acid (DA) was developed in this study. DA feed was prepared by mixing 0.15 mL 100 μg mL-1 DA with 0.1 g formulated feed, and drying the mixture at room temperature for 2 h. The prepared DA feed contained 0.19 pg DA per particle. Of the added DA, 46.72% was retained in the feed. Relatively high DA retention (about 50%) was recorded after DA feed was soaked in water for 2 h. Exposure to DA feed for 7 d did not cause the increase of tissue DA level of adult king scallop (Pecten maximus) significantly in 60 d. The increase of their gonad index after DA exposure was not significantly different from the control. No significant change in DA level was found in spermary, ovary or fertilized eggs after DA exposure. These results indicated that DA excretion may be more efficient than DA accumulation under the current experimental conditions, and the mechanism of domoic acid incorporation in P. maximus may involve intracellular biotransformation.展开更多
Advances in sensor technology have allowed the significant progress in the monitoring of noxious compounds in the sea, providing real-time detection so as to prevent risks associated with the diffusion and dispersion ...Advances in sensor technology have allowed the significant progress in the monitoring of noxious compounds in the sea, providing real-time detection so as to prevent risks associated with the diffusion and dispersion of toxic substances in the environment. An important element in the overall picture is the harmful algal blooms which pose serious threats to marine ecosystems through the production of toxins that accumulate in filter-feeders and ultimately impact both human health and fisheries. Domoic acid is a neurotoxic amino acid produced by marine planktonic diatoms of the genus Pseudo-nitzschia. Here we monitored domoic acid production by natural Pseudo-nitzschia populations in phytoplankton samples collected along the Middle Tyrrhenian coast, over the course of one year, using selective immunosensors based on screenprinted electrodes, using differential pulse voltammetry as the electrochemical technique, to yield quantitative outputs. In this work, disposable devices have been applied for monitoring the production of domoic acid on algal extracts and the results have been validated by conventional high pressure liquid chromatography-ultraviolet detection methods. The data obtained revealed the presence of domoic acid in Italian phytoplankton, especially in coastal impacted areas, highlighting the potential risk of toxin entering into marine food webs and the environment. Immunosensors based on screen-printed electrodes prove to be effective tools for annual monitoring of domoic acid in seawater samples, thus providing a reliable early warning system relative to health and economic impact of algal toxins.展开更多
The purpose of the present study was to determine whether early alterations in glutamate signaling, via daily injections of the glutamate agonist, domoic acid (DOM;20 μg/kg), during a critical period of CNS developme...The purpose of the present study was to determine whether early alterations in glutamate signaling, via daily injections of the glutamate agonist, domoic acid (DOM;20 μg/kg), during a critical period of CNS development (PND 8 - 14), would result in temporal memory deficits and/or alterations in tyrosine hydroxylase (TH) immunoreactivity. As adults, subjects were assessed for temporal memory ability using a recency discrimination paradigm. Both number and duration of exploratory contacts directed at familiar objects, differing by one hour in recall delay, were measured. Analyses revealed that DOM-treated females demonstrated temporal memory dysfunction, as evidenced in a significantly lower proportion of total exploratory behaviour directed toward the remote object. Integrity of the dopamine system was assessed using immunohistochemistry to examine TH immunoreactivity in the prefrontal cortex (PFC) and nucleus accumbens (NAcc). Sections obtained from DOM-treated males had significantly less TH immunoreactivity in the right mPFC, while DOM-treated females had significantly greater TH immunoreactivity in the left core and right shell of the NAcc. These findings are discussed in context of early alterations to glutamate signaling in the development of human neuropsychiatric disorders.展开更多
The clinical presentation of schizophrenia involves a variety of symptoms, which in many cases include hallucinations and delusions. Experimentally revealed alterations in both pre-pulse inhibition (PPI) and latent in...The clinical presentation of schizophrenia involves a variety of symptoms, which in many cases include hallucinations and delusions. Experimentally revealed alterations in both pre-pulse inhibition (PPI) and latent inhibition (LI) are also apparent in individuals afflicted with this disorder. Many have speculated that altered synaptic connections are, in part, responsible for this subset of behavioral abnormalities. We have previously reported that neonatal chronic low-dose injections of domoic acid (DOM) produce adult rats with deficits in PPI and LI. The current study was conducted to determine whether this toxin-treatment would alter the degree of apoptosis occurring in the developing brain. Results revealed significant decreases in caspase-3 within the right prelimbic cortex (PrL) in both male and female DOM-treated rats suggesting that even modest alterations in glutamate (Glu) signaling during critical periods of central nervous system (CNS) maturation will modify ontogenetic processes in the prefrontal cortex (PFC) of the juvenile rat.展开更多
目的探讨复苏后6 h静动脉二氧化碳含量差(Cv-aCO2)/动静脉氧含量差(Da-vO2)联合乳酸清除率对感染性休克患者预后的评估价值。方法选取感染性休克108例(≥18岁,原发病均为肺部感染),根据复苏后6 h Cv-aCO2/Da-vO2和乳酸清除率将其分为A、...目的探讨复苏后6 h静动脉二氧化碳含量差(Cv-aCO2)/动静脉氧含量差(Da-vO2)联合乳酸清除率对感染性休克患者预后的评估价值。方法选取感染性休克108例(≥18岁,原发病均为肺部感染),根据复苏后6 h Cv-aCO2/Da-vO2和乳酸清除率将其分为A、B、C和D组4组:A组21例,Cv-aCO2/Da-vO 2>1,乳酸清除率>0.10;B组38例,Cv-aCO2/Da-vO2>1,乳酸清除率≤0.10;C组26例,Cv-aCO2/Da-vO2≤1,乳酸清除率≤0.10;D组23例,Cv-aCO2/Da-vO2≤1,乳酸清除率>0.10。对复苏后6 h Cv-aCO2/Da-vO2、乳酸清除率和入组后第3天序贯器官衰竭评估(sequential organ failure assessment,SOFA)评分进行析因方差分析,并比较4组入组后第3天SOFA评分及入组后28 d全因病死率。结果析因方差分析结果显示,感染性休克108例复苏后6 h Cv-aCO2/Da-vO2与入组后第3天SOFA评分相关(P<0.01);复苏后6 h乳酸清除率与入组后第3天SOFA评分也相关(P<0.05)。One-way ANOVA统计分析结果显示,4组入组后第3天SOFA评分总体比较差异具有统计学意义(P<0.01)。4组入组后第3天SOFA评分两两比较结果显示,A组与B组和C组与D组比较差异无统计学意义(P>0.05);A组与C组、A组与D组、B组与C组和B组与D组比较差异有统计学意义(P<0.05或P<0.01)。A组入组后28 d全因病死率71.43%;B组入组后28 d全因病死率73.68%,C组入组后28 d全因病死率30.77%,D组入组后28 d全因病死率26.09%,4组入组后28 d全因病死率总体比较差异具有统计学意义(P<0.01);入组后28 d全因病死率A组与B组和C组与D组比较差异无统计学意义(P>0.05),A组与C组、A组与D组、B组与C组和B组与D组比较差异有统计学意义(P<0.01)。结论复苏后6 h Cv-aCO2/Da-vO2和乳酸清除率均可以预测感染性休克患者预后,但二者联合未显示出更优预测价值。展开更多
This paper describes a reliable and rapid method for the complete separation and quantitation of twenty-five amino acids typically found in plants, based on reversed phase high-performance liquid chromatography–linke...This paper describes a reliable and rapid method for the complete separation and quantitation of twenty-five amino acids typically found in plants, based on reversed phase high-performance liquid chromatography–linked fluorescence detector using a 150×4.6 mm Zorbax Eclipse AAA column. Plant tissue free amino acids(FAA)were extracted by ultrasonication with 5%(v/v) aqueous trifluoroacetic acid followed by ultrafiltration of extracts.The following analysis of amino acids was performed through programmed precolumn derivatization with orthophthalaldehyde and 9-fluorenylmethyl chloroformate reagents and efficient elution of derivatives within 26 min using binary gradient scheme. The method was validated over a concentration range of 4.5–450 μmol L^(-1)(μM).Separation analysis showed good selectivity(resolution>1.5) for most amino acids. The average repeatability(RSD%, relative standard deviation) of the analysis at seven calibration concentrations was below 4% and ranged from 1.13% to 12.04%. The intra-day mean coefficient of variation at two concentrations(22.5 and 90 μM) was within 2%, and the intermediate precision was less than 4%. The limits of detection were between 0.012 and 6.68 μM. The coefficients of determination(R2) of the linear calibration curves were from 0.9989 to 0.9999.When the method was applied to plant samples, the FAA recoveries at two spiked levels(25 and 100 μM) ranged from 67.0% to 108.9% with an average of 94.4%, and the precision was 0.26%–12.31% RSD. A specific application combining this method with optimized extraction and interference removal procedures was successfully used to determine the FAA pools in different plant tissues. Finally,a PLS-DA multivariate statistics model was validated for the classification of three plant species according to their FAA profiles.展开更多
基金Supported by the Science&Technology Basic Resources Investigation Program of China(No.2018FY100200)the National Natural Science Foundation of China(Nos.32072329,41976110)+1 种基金the Central PublicInterest Scientifi c Institution Basal Research Fund,CAFS(No.2020TD71)the Earmarked Fund for CARS(CARS-49)。
文摘A total of 133 shellfish samples were collected in seven cities of Shandong Province,China,from May to October,2019.The domoic acid(DA)concentrations were determined by liquid chromatographytandem mass spectrometry(LC-MS/MS),and their distribution characteristics were investigated.DA concentration was detected high in over 1/3(36.1%)of the samples of four kinds of shellfish in all three seasons in range from 0 to 102μg/kg.The highest DA concentrations were 102,101,36.7,and 10.2μg/kg in Crassostrea gigas,Chlamys farreri,Mactra veneriformis,and Mytilus edulis,respectively.Geographically,Yantai(22.0μg/kg)and Weihai(16.9μg/kg)showed relatively high concentrations of DA,whereas Rizhao and Dongying presented only 0.85-and 1.76-μg/kg DA,respectively.DA concentrations in the shellfish samples were strongly related to seasonal changes,being significantly higher in autumn and summer than that in spring.The DA risk exposure assessments indicate that dietary seafood consumption did not pose a health threat to general human population.In addition,three isomers(isoA,isoD,isoE)and 5′-epimer DA were detected in 3.00%-15.80%of the shellfish samples.This study is the first to observe DA and its isomers in shellfish samples of Shandong Province.The results demonstrate that DA contamination is very common and should be continuously monitored.
文摘A simple method for spiking formulated feed with domoic acid (DA) was developed in this study. DA feed was prepared by mixing 0.15 mL 100 μg mL-1 DA with 0.1 g formulated feed, and drying the mixture at room temperature for 2 h. The prepared DA feed contained 0.19 pg DA per particle. Of the added DA, 46.72% was retained in the feed. Relatively high DA retention (about 50%) was recorded after DA feed was soaked in water for 2 h. Exposure to DA feed for 7 d did not cause the increase of tissue DA level of adult king scallop (Pecten maximus) significantly in 60 d. The increase of their gonad index after DA exposure was not significantly different from the control. No significant change in DA level was found in spermary, ovary or fertilized eggs after DA exposure. These results indicated that DA excretion may be more efficient than DA accumulation under the current experimental conditions, and the mechanism of domoic acid incorporation in P. maximus may involve intracellular biotransformation.
文摘Advances in sensor technology have allowed the significant progress in the monitoring of noxious compounds in the sea, providing real-time detection so as to prevent risks associated with the diffusion and dispersion of toxic substances in the environment. An important element in the overall picture is the harmful algal blooms which pose serious threats to marine ecosystems through the production of toxins that accumulate in filter-feeders and ultimately impact both human health and fisheries. Domoic acid is a neurotoxic amino acid produced by marine planktonic diatoms of the genus Pseudo-nitzschia. Here we monitored domoic acid production by natural Pseudo-nitzschia populations in phytoplankton samples collected along the Middle Tyrrhenian coast, over the course of one year, using selective immunosensors based on screenprinted electrodes, using differential pulse voltammetry as the electrochemical technique, to yield quantitative outputs. In this work, disposable devices have been applied for monitoring the production of domoic acid on algal extracts and the results have been validated by conventional high pressure liquid chromatography-ultraviolet detection methods. The data obtained revealed the presence of domoic acid in Italian phytoplankton, especially in coastal impacted areas, highlighting the potential risk of toxin entering into marine food webs and the environment. Immunosensors based on screen-printed electrodes prove to be effective tools for annual monitoring of domoic acid in seawater samples, thus providing a reliable early warning system relative to health and economic impact of algal toxins.
文摘The purpose of the present study was to determine whether early alterations in glutamate signaling, via daily injections of the glutamate agonist, domoic acid (DOM;20 μg/kg), during a critical period of CNS development (PND 8 - 14), would result in temporal memory deficits and/or alterations in tyrosine hydroxylase (TH) immunoreactivity. As adults, subjects were assessed for temporal memory ability using a recency discrimination paradigm. Both number and duration of exploratory contacts directed at familiar objects, differing by one hour in recall delay, were measured. Analyses revealed that DOM-treated females demonstrated temporal memory dysfunction, as evidenced in a significantly lower proportion of total exploratory behaviour directed toward the remote object. Integrity of the dopamine system was assessed using immunohistochemistry to examine TH immunoreactivity in the prefrontal cortex (PFC) and nucleus accumbens (NAcc). Sections obtained from DOM-treated males had significantly less TH immunoreactivity in the right mPFC, while DOM-treated females had significantly greater TH immunoreactivity in the left core and right shell of the NAcc. These findings are discussed in context of early alterations to glutamate signaling in the development of human neuropsychiatric disorders.
文摘The clinical presentation of schizophrenia involves a variety of symptoms, which in many cases include hallucinations and delusions. Experimentally revealed alterations in both pre-pulse inhibition (PPI) and latent inhibition (LI) are also apparent in individuals afflicted with this disorder. Many have speculated that altered synaptic connections are, in part, responsible for this subset of behavioral abnormalities. We have previously reported that neonatal chronic low-dose injections of domoic acid (DOM) produce adult rats with deficits in PPI and LI. The current study was conducted to determine whether this toxin-treatment would alter the degree of apoptosis occurring in the developing brain. Results revealed significant decreases in caspase-3 within the right prelimbic cortex (PrL) in both male and female DOM-treated rats suggesting that even modest alterations in glutamate (Glu) signaling during critical periods of central nervous system (CNS) maturation will modify ontogenetic processes in the prefrontal cortex (PFC) of the juvenile rat.
文摘目的探讨复苏后6 h静动脉二氧化碳含量差(Cv-aCO2)/动静脉氧含量差(Da-vO2)联合乳酸清除率对感染性休克患者预后的评估价值。方法选取感染性休克108例(≥18岁,原发病均为肺部感染),根据复苏后6 h Cv-aCO2/Da-vO2和乳酸清除率将其分为A、B、C和D组4组:A组21例,Cv-aCO2/Da-vO 2>1,乳酸清除率>0.10;B组38例,Cv-aCO2/Da-vO2>1,乳酸清除率≤0.10;C组26例,Cv-aCO2/Da-vO2≤1,乳酸清除率≤0.10;D组23例,Cv-aCO2/Da-vO2≤1,乳酸清除率>0.10。对复苏后6 h Cv-aCO2/Da-vO2、乳酸清除率和入组后第3天序贯器官衰竭评估(sequential organ failure assessment,SOFA)评分进行析因方差分析,并比较4组入组后第3天SOFA评分及入组后28 d全因病死率。结果析因方差分析结果显示,感染性休克108例复苏后6 h Cv-aCO2/Da-vO2与入组后第3天SOFA评分相关(P<0.01);复苏后6 h乳酸清除率与入组后第3天SOFA评分也相关(P<0.05)。One-way ANOVA统计分析结果显示,4组入组后第3天SOFA评分总体比较差异具有统计学意义(P<0.01)。4组入组后第3天SOFA评分两两比较结果显示,A组与B组和C组与D组比较差异无统计学意义(P>0.05);A组与C组、A组与D组、B组与C组和B组与D组比较差异有统计学意义(P<0.05或P<0.01)。A组入组后28 d全因病死率71.43%;B组入组后28 d全因病死率73.68%,C组入组后28 d全因病死率30.77%,D组入组后28 d全因病死率26.09%,4组入组后28 d全因病死率总体比较差异具有统计学意义(P<0.01);入组后28 d全因病死率A组与B组和C组与D组比较差异无统计学意义(P>0.05),A组与C组、A组与D组、B组与C组和B组与D组比较差异有统计学意义(P<0.01)。结论复苏后6 h Cv-aCO2/Da-vO2和乳酸清除率均可以预测感染性休克患者预后,但二者联合未显示出更优预测价值。
基金financially supported by the National Key Research and Development Program of China through Grant 2016YFA0601000(H.Y.Xiao)National Natural Science Foundation of China through Grants 41425014,41273027 and 41173027(H.Y.Xiao)by the National Basic Research Program of China through Grants 2013CB956703(H.Y.Xiao)
文摘This paper describes a reliable and rapid method for the complete separation and quantitation of twenty-five amino acids typically found in plants, based on reversed phase high-performance liquid chromatography–linked fluorescence detector using a 150×4.6 mm Zorbax Eclipse AAA column. Plant tissue free amino acids(FAA)were extracted by ultrasonication with 5%(v/v) aqueous trifluoroacetic acid followed by ultrafiltration of extracts.The following analysis of amino acids was performed through programmed precolumn derivatization with orthophthalaldehyde and 9-fluorenylmethyl chloroformate reagents and efficient elution of derivatives within 26 min using binary gradient scheme. The method was validated over a concentration range of 4.5–450 μmol L^(-1)(μM).Separation analysis showed good selectivity(resolution>1.5) for most amino acids. The average repeatability(RSD%, relative standard deviation) of the analysis at seven calibration concentrations was below 4% and ranged from 1.13% to 12.04%. The intra-day mean coefficient of variation at two concentrations(22.5 and 90 μM) was within 2%, and the intermediate precision was less than 4%. The limits of detection were between 0.012 and 6.68 μM. The coefficients of determination(R2) of the linear calibration curves were from 0.9989 to 0.9999.When the method was applied to plant samples, the FAA recoveries at two spiked levels(25 and 100 μM) ranged from 67.0% to 108.9% with an average of 94.4%, and the precision was 0.26%–12.31% RSD. A specific application combining this method with optimized extraction and interference removal procedures was successfully used to determine the FAA pools in different plant tissues. Finally,a PLS-DA multivariate statistics model was validated for the classification of three plant species according to their FAA profiles.