The Experts below are selected from a list of 1572 Experts worldwide ranked by ideXlab platform
I Zagnoni - One of the best experts on this subject based on the ideXlab platform.
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development and in house validation of a liquid chromatography electrospray tandem mass spectrometry method for the simultaneous determination of Sudan i Sudan ii Sudan iii and Sudan IV in hot chilli products
Journal of Chromatography A, 2004Co-Authors: F Calbiani, Maria Careri, Lisa Elviri, A Mangia, L Pistara, I ZagnoniAbstract:Abstract An accurate method based on the use of reversed-phase (RP) liquid chromatography–tandem mass spectrometry interfaced with electrospray (LC–ESI–MS/MS) was devised for the determination of Sudan I, Sudan II, Sudan III and Sudan IV in hot chilli food samples. A simple sample treatment procedure entailing the use of an extraction step with acetone without clean-up was developed. A C18 column with an aqueous formic acid/methanol mixture as the mobile phase was used under isocratic conditions. Mass spectral acquisition was done in positIVe ion mode by applying selected reaction monitoring of three fragmentation transitions per compound to provide a high degree of selectIVity. The method was in-house validated in terms of detection limits (LOD), quantitation limits (LOQ), linearity, sensitIVity, accuracy, recovery, and selectIVity on two kinds of hot chilli sauces. Good results in the low ng/g level were obtained for LOD and LOQ of all analytes in matrices. Under both intra-day repeatability (R.S.D. between 1 and 13%) and intermediate precision (about 5–15% R.S.D. for both chilli sauce matrices) conditions, precision proved to be typical of determinations based on electrospray LC–MS and acceptable for routine monitoring purposes. Extraction recoveries for all four azo-dyes in chilli tomato sauce ranged from 92 to 103% at a spiking level of 5 μg/kg, whereas values between 72 and 97% were calculated in chilli tomato and cheese sauce at the same concentration level. The applicability of the method to the determination of Sudan azo-dyes in hot chilli products was demonstrated.
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development and in house validation of a liquid chromatography electrospray tandem mass spectrometry method for the simultaneous determination of Sudan i Sudan ii Sudan iii and Sudan IV in hot chilli products
Journal of Chromatography A, 2004Co-Authors: F Calbiani, Maria Careri, Lisa Elviri, A Mangia, L Pistara, I ZagnoniAbstract:Abstract An accurate method based on the use of reversed-phase (RP) liquid chromatography–tandem mass spectrometry interfaced with electrospray (LC–ESI–MS/MS) was devised for the determination of Sudan I, Sudan II, Sudan III and Sudan IV in hot chilli food samples. A simple sample treatment procedure entailing the use of an extraction step with acetone without clean-up was developed. A C18 column with an aqueous formic acid/methanol mixture as the mobile phase was used under isocratic conditions. Mass spectral acquisition was done in positIVe ion mode by applying selected reaction monitoring of three fragmentation transitions per compound to provide a high degree of selectIVity. The method was in-house validated in terms of detection limits (LOD), quantitation limits (LOQ), linearity, sensitIVity, accuracy, recovery, and selectIVity on two kinds of hot chilli sauces. Good results in the low ng/g level were obtained for LOD and LOQ of all analytes in matrices. Under both intra-day repeatability (R.S.D. between 1 and 13%) and intermediate precision (about 5–15% R.S.D. for both chilli sauce matrices) conditions, precision proved to be typical of determinations based on electrospray LC–MS and acceptable for routine monitoring purposes. Extraction recoveries for all four azo-dyes in chilli tomato sauce ranged from 92 to 103% at a spiking level of 5 μg/kg, whereas values between 72 and 97% were calculated in chilli tomato and cheese sauce at the same concentration level. The applicability of the method to the determination of Sudan azo-dyes in hot chilli products was demonstrated.
Joseph J Boyle - One of the best experts on this subject based on the ideXlab platform.
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decay accelerating factor suppresses complement c3 actIVation and retards atherosclerosis in low density lipoprotein receptor deficient mice
American Journal of Pathology, 2009Co-Authors: Viola Leung, Marina Botto, Joseph J Boyle, Justin C Mason, Talat H Malik, Wenchao Song, Danielle Paixaocavalcante, Matthew C PickeringAbstract:Decay-accelerating factor (DAF; CD55) is a membrane protein that regulates complement pathway actIVity at the level of C3. To test the hypothesis that DAF plays an essential role in limiting complement actIVation in the arterial wall and protecting from atherosclerosis, we crossed DAF gene targeted mice (daf-1−/−) with low-density lipoprotein-receptor deficient mice (Ldlr−/−). Daf-1−/−Ldlr−/− mice had more extensIVe en face Sudan IV staining of the thoracoabdominal aorta than Ldlr−/− mice, both following a 12-week period of low-fat diet or a high-fat diet. Aortic root lesions in daf-1−/−Ldlr−/− mice on a low-fat diet showed increased size and complexity. DAF deficiency increased deposition of C3d and C5b-9, indicating the importance of DAF for downstream complement regulation in the arterial wall. The acceleration of lesion development in the absence of DAF provides confirmation of the proinflammatory and proatherosclerotic potential of complement actIVation in the Ldlr−/− mouse model. Because upstream complement actIVation is potentially protectIVe, this study underlines the importance of DAF in shielding the arterial wall from the atherogenic effects of complement.
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brief report accelerated atherosclerosis in low density lipoprotein receptor deficient mice lacking the membrane bound complement regulator cd59
Arteriosclerosis Thrombosis and Vascular Biology, 2008Co-Authors: Sheng Yun, Viola Leung, Marina Botto, Joseph J Boyle, Dorian O HaskardAbstract:ObjectIVe— Whereas studies in humans and animal models have suggested a role for complement actIVation in atherosclerosis, there has been little analysis of the importance of complement regulators. We tested the hypothesis that the terminal pathway inhibitor CD59 plays an essential role in limiting the proinflammatory effects of complement actIVation. Methods and Results— CD59 gene targeted mice ( CD59a −/− ) mice were crossed with low-density lipoprotein receptor-deficient ( Ldlr −/− ) mice. CD59-deficient Ldlr −/− mice had significantly more extensIVe en face Sudan IV staining of thoracoabdominal aorta than Ldlr −/− single knock-outs, both after a low-fat diet (6.51±0.36% versus 2.63±0.56%, P P CD59a −/− / Ldlr −/− mice on a high-fat diet was associated with increased lesional vascular smooth muscle cell (VSMC) number and fibrous cap formation. Conclusion— Our data show that CD59 deficiency accelerates the development of lesions and increases plaque VSMC composition. Assuming that the main function of CD59 is to prevent the development of C5b-9 membrane attack complexes, our observations are consistent with the terminal complement pathway having proatherogenic potential in the Ldlr −/− mouse model, and highlight the importance of complement regulation.
F Calbiani - One of the best experts on this subject based on the ideXlab platform.
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development and in house validation of a liquid chromatography electrospray tandem mass spectrometry method for the simultaneous determination of Sudan i Sudan ii Sudan iii and Sudan IV in hot chilli products
Journal of Chromatography A, 2004Co-Authors: F Calbiani, Maria Careri, Lisa Elviri, A Mangia, L Pistara, I ZagnoniAbstract:Abstract An accurate method based on the use of reversed-phase (RP) liquid chromatography–tandem mass spectrometry interfaced with electrospray (LC–ESI–MS/MS) was devised for the determination of Sudan I, Sudan II, Sudan III and Sudan IV in hot chilli food samples. A simple sample treatment procedure entailing the use of an extraction step with acetone without clean-up was developed. A C18 column with an aqueous formic acid/methanol mixture as the mobile phase was used under isocratic conditions. Mass spectral acquisition was done in positIVe ion mode by applying selected reaction monitoring of three fragmentation transitions per compound to provide a high degree of selectIVity. The method was in-house validated in terms of detection limits (LOD), quantitation limits (LOQ), linearity, sensitIVity, accuracy, recovery, and selectIVity on two kinds of hot chilli sauces. Good results in the low ng/g level were obtained for LOD and LOQ of all analytes in matrices. Under both intra-day repeatability (R.S.D. between 1 and 13%) and intermediate precision (about 5–15% R.S.D. for both chilli sauce matrices) conditions, precision proved to be typical of determinations based on electrospray LC–MS and acceptable for routine monitoring purposes. Extraction recoveries for all four azo-dyes in chilli tomato sauce ranged from 92 to 103% at a spiking level of 5 μg/kg, whereas values between 72 and 97% were calculated in chilli tomato and cheese sauce at the same concentration level. The applicability of the method to the determination of Sudan azo-dyes in hot chilli products was demonstrated.
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development and in house validation of a liquid chromatography electrospray tandem mass spectrometry method for the simultaneous determination of Sudan i Sudan ii Sudan iii and Sudan IV in hot chilli products
Journal of Chromatography A, 2004Co-Authors: F Calbiani, Maria Careri, Lisa Elviri, A Mangia, L Pistara, I ZagnoniAbstract:Abstract An accurate method based on the use of reversed-phase (RP) liquid chromatography–tandem mass spectrometry interfaced with electrospray (LC–ESI–MS/MS) was devised for the determination of Sudan I, Sudan II, Sudan III and Sudan IV in hot chilli food samples. A simple sample treatment procedure entailing the use of an extraction step with acetone without clean-up was developed. A C18 column with an aqueous formic acid/methanol mixture as the mobile phase was used under isocratic conditions. Mass spectral acquisition was done in positIVe ion mode by applying selected reaction monitoring of three fragmentation transitions per compound to provide a high degree of selectIVity. The method was in-house validated in terms of detection limits (LOD), quantitation limits (LOQ), linearity, sensitIVity, accuracy, recovery, and selectIVity on two kinds of hot chilli sauces. Good results in the low ng/g level were obtained for LOD and LOQ of all analytes in matrices. Under both intra-day repeatability (R.S.D. between 1 and 13%) and intermediate precision (about 5–15% R.S.D. for both chilli sauce matrices) conditions, precision proved to be typical of determinations based on electrospray LC–MS and acceptable for routine monitoring purposes. Extraction recoveries for all four azo-dyes in chilli tomato sauce ranged from 92 to 103% at a spiking level of 5 μg/kg, whereas values between 72 and 97% were calculated in chilli tomato and cheese sauce at the same concentration level. The applicability of the method to the determination of Sudan azo-dyes in hot chilli products was demonstrated.
Viola Leung - One of the best experts on this subject based on the ideXlab platform.
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decay accelerating factor suppresses complement c3 actIVation and retards atherosclerosis in low density lipoprotein receptor deficient mice
American Journal of Pathology, 2009Co-Authors: Viola Leung, Marina Botto, Joseph J Boyle, Justin C Mason, Talat H Malik, Wenchao Song, Danielle Paixaocavalcante, Matthew C PickeringAbstract:Decay-accelerating factor (DAF; CD55) is a membrane protein that regulates complement pathway actIVity at the level of C3. To test the hypothesis that DAF plays an essential role in limiting complement actIVation in the arterial wall and protecting from atherosclerosis, we crossed DAF gene targeted mice (daf-1−/−) with low-density lipoprotein-receptor deficient mice (Ldlr−/−). Daf-1−/−Ldlr−/− mice had more extensIVe en face Sudan IV staining of the thoracoabdominal aorta than Ldlr−/− mice, both following a 12-week period of low-fat diet or a high-fat diet. Aortic root lesions in daf-1−/−Ldlr−/− mice on a low-fat diet showed increased size and complexity. DAF deficiency increased deposition of C3d and C5b-9, indicating the importance of DAF for downstream complement regulation in the arterial wall. The acceleration of lesion development in the absence of DAF provides confirmation of the proinflammatory and proatherosclerotic potential of complement actIVation in the Ldlr−/− mouse model. Because upstream complement actIVation is potentially protectIVe, this study underlines the importance of DAF in shielding the arterial wall from the atherogenic effects of complement.
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brief report accelerated atherosclerosis in low density lipoprotein receptor deficient mice lacking the membrane bound complement regulator cd59
Arteriosclerosis Thrombosis and Vascular Biology, 2008Co-Authors: Sheng Yun, Viola Leung, Marina Botto, Joseph J Boyle, Dorian O HaskardAbstract:ObjectIVe— Whereas studies in humans and animal models have suggested a role for complement actIVation in atherosclerosis, there has been little analysis of the importance of complement regulators. We tested the hypothesis that the terminal pathway inhibitor CD59 plays an essential role in limiting the proinflammatory effects of complement actIVation. Methods and Results— CD59 gene targeted mice ( CD59a −/− ) mice were crossed with low-density lipoprotein receptor-deficient ( Ldlr −/− ) mice. CD59-deficient Ldlr −/− mice had significantly more extensIVe en face Sudan IV staining of thoracoabdominal aorta than Ldlr −/− single knock-outs, both after a low-fat diet (6.51±0.36% versus 2.63±0.56%, P P CD59a −/− / Ldlr −/− mice on a high-fat diet was associated with increased lesional vascular smooth muscle cell (VSMC) number and fibrous cap formation. Conclusion— Our data show that CD59 deficiency accelerates the development of lesions and increases plaque VSMC composition. Assuming that the main function of CD59 is to prevent the development of C5b-9 membrane attack complexes, our observations are consistent with the terminal complement pathway having proatherogenic potential in the Ldlr −/− mouse model, and highlight the importance of complement regulation.
Lisa Elviri - One of the best experts on this subject based on the ideXlab platform.
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development and in house validation of a liquid chromatography electrospray tandem mass spectrometry method for the simultaneous determination of Sudan i Sudan ii Sudan iii and Sudan IV in hot chilli products
Journal of Chromatography A, 2004Co-Authors: F Calbiani, Maria Careri, Lisa Elviri, A Mangia, L Pistara, I ZagnoniAbstract:Abstract An accurate method based on the use of reversed-phase (RP) liquid chromatography–tandem mass spectrometry interfaced with electrospray (LC–ESI–MS/MS) was devised for the determination of Sudan I, Sudan II, Sudan III and Sudan IV in hot chilli food samples. A simple sample treatment procedure entailing the use of an extraction step with acetone without clean-up was developed. A C18 column with an aqueous formic acid/methanol mixture as the mobile phase was used under isocratic conditions. Mass spectral acquisition was done in positIVe ion mode by applying selected reaction monitoring of three fragmentation transitions per compound to provide a high degree of selectIVity. The method was in-house validated in terms of detection limits (LOD), quantitation limits (LOQ), linearity, sensitIVity, accuracy, recovery, and selectIVity on two kinds of hot chilli sauces. Good results in the low ng/g level were obtained for LOD and LOQ of all analytes in matrices. Under both intra-day repeatability (R.S.D. between 1 and 13%) and intermediate precision (about 5–15% R.S.D. for both chilli sauce matrices) conditions, precision proved to be typical of determinations based on electrospray LC–MS and acceptable for routine monitoring purposes. Extraction recoveries for all four azo-dyes in chilli tomato sauce ranged from 92 to 103% at a spiking level of 5 μg/kg, whereas values between 72 and 97% were calculated in chilli tomato and cheese sauce at the same concentration level. The applicability of the method to the determination of Sudan azo-dyes in hot chilli products was demonstrated.
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development and in house validation of a liquid chromatography electrospray tandem mass spectrometry method for the simultaneous determination of Sudan i Sudan ii Sudan iii and Sudan IV in hot chilli products
Journal of Chromatography A, 2004Co-Authors: F Calbiani, Maria Careri, Lisa Elviri, A Mangia, L Pistara, I ZagnoniAbstract:Abstract An accurate method based on the use of reversed-phase (RP) liquid chromatography–tandem mass spectrometry interfaced with electrospray (LC–ESI–MS/MS) was devised for the determination of Sudan I, Sudan II, Sudan III and Sudan IV in hot chilli food samples. A simple sample treatment procedure entailing the use of an extraction step with acetone without clean-up was developed. A C18 column with an aqueous formic acid/methanol mixture as the mobile phase was used under isocratic conditions. Mass spectral acquisition was done in positIVe ion mode by applying selected reaction monitoring of three fragmentation transitions per compound to provide a high degree of selectIVity. The method was in-house validated in terms of detection limits (LOD), quantitation limits (LOQ), linearity, sensitIVity, accuracy, recovery, and selectIVity on two kinds of hot chilli sauces. Good results in the low ng/g level were obtained for LOD and LOQ of all analytes in matrices. Under both intra-day repeatability (R.S.D. between 1 and 13%) and intermediate precision (about 5–15% R.S.D. for both chilli sauce matrices) conditions, precision proved to be typical of determinations based on electrospray LC–MS and acceptable for routine monitoring purposes. Extraction recoveries for all four azo-dyes in chilli tomato sauce ranged from 92 to 103% at a spiking level of 5 μg/kg, whereas values between 72 and 97% were calculated in chilli tomato and cheese sauce at the same concentration level. The applicability of the method to the determination of Sudan azo-dyes in hot chilli products was demonstrated.
