Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is k...Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is known about the long-term stability of these biomarker proteins in plasma samples stored at-80°C.We aimed to explore how storage time would affect the diagnostic accuracy of these biomarkers using a large cohort.Plasma samples from 229 cognitively unimpaired individuals,encompassing healthy controls and those experiencing subjective cognitive decline,as well as 99 patients with cognitive impairment,comprising those with mild cognitive impairment and dementia,were acquired from the Sino Longitudinal Study on Cognitive Decline project.These samples were stored at-80°C for up to 6 years before being used in this study.Our results showed that plasma levels of Aβ42,Aβ40,neurofilament light chain,and glial fibrillary acidic protein were not significantly correlated with sample storage time.However,the level of total tau showed a negative correlation with sample storage time.Notably,in individuals without cognitive impairment,plasma levels of total protein and tau phosphorylated protein threonine 181(p-tau181)also showed a negative correlation with sample storage time.This was not observed in individuals with cognitive impairment.Consequently,we speculate that the diagnostic accuracy of plasma p-tau181 and the p-tau181 to total tau ratio may be influenced by sample storage time.Therefore,caution is advised when using these plasma biomarkers for the identification of neurodegenerative diseases,such as Alzheimer's disease.Furthermore,in cohort studies,it is important to consider the impact of storage time on the overall results.展开更多
AIM:To determine the diagnostic ability of various visual functions in patients with multiple sclerosis(MS)with and without optic neuritis(ON).METHODS:In this cross-sectional study,we assessed and compared refractive ...AIM:To determine the diagnostic ability of various visual functions in patients with multiple sclerosis(MS)with and without optic neuritis(ON).METHODS:In this cross-sectional study,we assessed and compared refractive error,visual acuity(VA),and contrast sensitivity(CS)between patients with MS and a matched control group of healthy individuals.The MS patients were further categorized into those with ON and those without.RESULTS:A total of 133 eyes from 133 participants were assessed,including 66 individuals diagnosed with MS.The mean ages for the MS group and the healthy control group were 37.5±4.27y and 38.45±4.60y,respectively(P=0.346).Among the 66 patients with MS,18 had ON.The presence of MS was associated with a decrease in best-corrected visual acuity(BCVA)and spherical component of refractive error(P<0.05),whereas ON did not lead to any further decline in these parameters(P>0.05).MS was linked to decreased CS at spatial frequencies of 6 and 18 cycles per degree(CPD;P<0.05),while ON in MS patients resulted in an additional decrease in CS at 3 CPD(P=0.03).The most significant sensitivity for distinguishing MS patients from healthy individuals as well as MS patients with ON from those without ON was found with cylindrical component[associated criterion(AC)>-0.75 D;71.21%]and CS at spatial frequency of 6 CPD(AC≤1.56;72.22%),respectively.Conversely,the highest specificity for these diagnostic measures was associated with BCVA(AC>0 logMAR;97.01%)and CS at a spatial frequency of 12 CPD(AC≤0.60;93.75%),respectively.CONCLUSION:MS significantly affects refractive error and CS,with ON further reducing CS.Assessing these visual parameters can improve MS monitoring and management.展开更多
基金supported by the National Key Research&Development Program of China,Nos.2021YFC2501205(to YC),2022YFC24069004(to JL)the STI2030-Major Project,Nos.2021ZD0201101(to YC),2022ZD0211800(to YH)+2 种基金the National Natural Science Foundation of China(Major International Joint Research Project),No.82020108013(to YH)the Sino-German Center for Research Promotion,No.M-0759(to YH)a grant from Beijing Municipal Science&Technology Commission(Beijing Brain Initiative),No.Z201100005520018(to JL)。
文摘Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is known about the long-term stability of these biomarker proteins in plasma samples stored at-80°C.We aimed to explore how storage time would affect the diagnostic accuracy of these biomarkers using a large cohort.Plasma samples from 229 cognitively unimpaired individuals,encompassing healthy controls and those experiencing subjective cognitive decline,as well as 99 patients with cognitive impairment,comprising those with mild cognitive impairment and dementia,were acquired from the Sino Longitudinal Study on Cognitive Decline project.These samples were stored at-80°C for up to 6 years before being used in this study.Our results showed that plasma levels of Aβ42,Aβ40,neurofilament light chain,and glial fibrillary acidic protein were not significantly correlated with sample storage time.However,the level of total tau showed a negative correlation with sample storage time.Notably,in individuals without cognitive impairment,plasma levels of total protein and tau phosphorylated protein threonine 181(p-tau181)also showed a negative correlation with sample storage time.This was not observed in individuals with cognitive impairment.Consequently,we speculate that the diagnostic accuracy of plasma p-tau181 and the p-tau181 to total tau ratio may be influenced by sample storage time.Therefore,caution is advised when using these plasma biomarkers for the identification of neurodegenerative diseases,such as Alzheimer's disease.Furthermore,in cohort studies,it is important to consider the impact of storage time on the overall results.
文摘AIM:To determine the diagnostic ability of various visual functions in patients with multiple sclerosis(MS)with and without optic neuritis(ON).METHODS:In this cross-sectional study,we assessed and compared refractive error,visual acuity(VA),and contrast sensitivity(CS)between patients with MS and a matched control group of healthy individuals.The MS patients were further categorized into those with ON and those without.RESULTS:A total of 133 eyes from 133 participants were assessed,including 66 individuals diagnosed with MS.The mean ages for the MS group and the healthy control group were 37.5±4.27y and 38.45±4.60y,respectively(P=0.346).Among the 66 patients with MS,18 had ON.The presence of MS was associated with a decrease in best-corrected visual acuity(BCVA)and spherical component of refractive error(P<0.05),whereas ON did not lead to any further decline in these parameters(P>0.05).MS was linked to decreased CS at spatial frequencies of 6 and 18 cycles per degree(CPD;P<0.05),while ON in MS patients resulted in an additional decrease in CS at 3 CPD(P=0.03).The most significant sensitivity for distinguishing MS patients from healthy individuals as well as MS patients with ON from those without ON was found with cylindrical component[associated criterion(AC)>-0.75 D;71.21%]and CS at spatial frequency of 6 CPD(AC≤1.56;72.22%),respectively.Conversely,the highest specificity for these diagnostic measures was associated with BCVA(AC>0 logMAR;97.01%)and CS at a spatial frequency of 12 CPD(AC≤0.60;93.75%),respectively.CONCLUSION:MS significantly affects refractive error and CS,with ON further reducing CS.Assessing these visual parameters can improve MS monitoring and management.
