Context: Vitamin E is a powerful antioxidant and plays an important role in human reproduction. However, micronutrient deficiency is a major public health problem, particularly in developing countries. This study aime...Context: Vitamin E is a powerful antioxidant and plays an important role in human reproduction. However, micronutrient deficiency is a major public health problem, particularly in developing countries. This study aimed to establish reference intervals (RIs) for vitamin E in black Congolese people of childbearing age using an ELISA method to provide a reference for clinically assessing vitamin E status. Methods: A total of 127 healthy people between the ages of 20 and 42 who underwent check-ups were randomly selected for the study. ELISA method measured the level of vitamin E. The effect of gender on vitamin E level was assessed, and RI was established using a parametric approach. Results: Women showed significantly higher levels of vitamin E than men (p = 0.01). The RI of vitamin E in people of childbearing age was 3.71 to 13.72, 4.52 to 14.64, and 4.17 to 13.52 mg/L, respectively, for the whole population, women and men. Conclusion: Using an ELISA method, this study established RI for vitamin E in the black Congolese population of childbearing age. We also found that women had significantly higher vitamin E levels than men. The results could provide a scientific basis for interpreting vitamin status in people of childbearing age in our setting.展开更多
BACKGROUND The indirect methods of reference intervals(RI)establishment based on data mining are utilized to overcome the ethical,practical challenges and the cost associated with the conventional direct approach.AIM ...BACKGROUND The indirect methods of reference intervals(RI)establishment based on data mining are utilized to overcome the ethical,practical challenges and the cost associated with the conventional direct approach.AIM To generate RIs for serum creatinine in children and adolescents using an indirect statistical tool.METHODS Data mining of the laboratory information system was performed for serum creatinine analyzed from birth to 17 years for both genders.The timeline was set at six years from January 2013 to December 2018.Microsoft Excel 2010 and an indirect algorithm developed by the German Society of Clinical Chemistry and Laboratory Medicine’s Working Group on Guide Limits were used for the data analysis.RESULTS Data were extracted from 96104 samples and after excluding multiple samples for the same individual,we calculated RIs for 21920 males and 14846 females,with stratification into six discrete age groups.CONCLUSION Serum creatinine dynamics varied significantly across gender and age groups.展开更多
Objective:To demonstrate that serum follicle-stimulating hormone(FSH)in men rises with age,and to explore FSH reference intervals of age-related partitioning.Methods:Men aged 20-50 years(n=1190)underwent semen analysi...Objective:To demonstrate that serum follicle-stimulating hormone(FSH)in men rises with age,and to explore FSH reference intervals of age-related partitioning.Methods:Men aged 20-50 years(n=1190)underwent semen analysis according to World Health Organization(2010)methods.Serum was frozen prior to measurement of FSH by using the Siemens ADVIA Centaur®XP immunoassay system.FSH central 95%intervals after logarithmic transformation based on age were derived from 1037 normozoospermic men.These were then applied to oligozoospermic and azoospermic men.Men producing azoospermic semen samples were further classified as having non-obstructive azoospermia by clinical diagnostic criteria,including genetic analysis and surgical exploration.Results:Serum FSH in normozoospermic men increased with age(P<0.05),and reference intervals were determined with 10-year brackets:21-30 years[(1.0-8.2)IU/L],31-40 years[(1.4-9.5)IU/L],41-50 years[(1.9-12.0)IU/L].The proportion of oligozoospermic men with normal FSH concentrations was less than the normozoospermic men,which in turn was lower among azoospermic men(both P<0.01).The azoospermic men were further broken down according to the nature of the azoospermia as either obstructive or non-obstructive azoospermia,and 86.4%(38/44)men with non-obstructive azoospermia had elevated serum FSH concentrations whereas only 6.7%(1/15)men with obstructive azoospermia had high FSH levels,and this was significantly different(P<0.01).Conclusions:FSH concentrations increase in men between 20-50 years,and clinical interpretation of serum FSH results in men must be made by using age-based reference intervals.展开更多
Background The development and growth of children influence values of liver function tests.This study aims to establish age-and gender-specific pediatric reference intervals of liver function among Han children in Cha...Background The development and growth of children influence values of liver function tests.This study aims to establish age-and gender-specific pediatric reference intervals of liver function among Han children in Changchun,China.Methods A total of 1394 healthy Han children,aged 2-14 years,were recruited from communities and schools with informed parental consent in Changchun.The levels of serum alanine aminotransferase(ALT),aspartate aminotransferase(AST),y-glutamyltransferase(GGT),alkaline phosphatase(ALP),total protein(TP),albumin(ALB),total bilirubin(TBIL)and direct bilirubin(DBIL)were measured on Hitachi 7600-210 automatic biochemical analyzer.The age-and gender-specific reference intervals were partitioned using Harris and Boyd's test and calculated using nonparametric rank method.The pediatric reference intervals were validated in five representative hospitals located in different areas in Changchun.Results All the analytes required some levels of age partitioning.Proteins(TP,ALB)and bilirubins(TBIL,DBIL)required no gender partitioning.In contrast,considerable gender partitioning was required for serum ALT,AST,GGT,and ALP.TP,TBIL,and DBIL showed steady increases,and AST showed apparent decreases over time,whereas ALT,GGT,ALP,and ALB demonstrated complex trends of change.ALT and GGT increased sharply in males from 11 to 14 years old.However,ALP declined in females from 13 to 14 years.All five laboratories passed the validation of reference intervals.Conclusions There were apparent age or gender variations of the reference intervals for liver function.When establishing pediatric reference intervals,partitioning according to age and gender is necessary.展开更多
Background Cystatin C(Cys-C)is an emerging biomarker of renal diseases and its clinical use,particularly for screening the communities affected by chronic kidney disease of unknown etiology(CKDu),is hindered due to th...Background Cystatin C(Cys-C)is an emerging biomarker of renal diseases and its clinical use,particularly for screening the communities affected by chronic kidney disease of unknown etiology(CKDu),is hindered due to the lack of reference intervals(RIs)for diverse ethnic and age groups.The present study aimed to define RIs for urinary Cys-C(uCys-C)for a healthy pediatric population in Sri Lanka and in turn compare the renal function of the residential children in CKDu endemic and non-endemic regions in Sri Lanka.Methods A cross-sectional study was conducted with 850 healthy children(10-17 years)from selected locations for reference interval establishment,while a total of 892 children were recruited for the comparative study.Urine samples were collected and analyzed for Cys-C,creatinine(Cr)and albumin.Cr-adjusted uCys-C levels were partitioned by age,and RIs were determined with quantile regression(2.5th,50th and 97.5th quantiles)at 90%confidence interval.Results The range of median RIs for uCys-C in healthy children was 45.94-64.44 ng/mg Cr for boys and 53.58-69.97 ng/mg Cr for girls.The median(interquartile range)uCys-C levels of children in the CKDu endemic and non-endemic regions were 58.18(21.8-141.9)and 58.31(23.9-155.3)ng/mg Cr with no significant difference(P=0.781).A significant variation of uCys-C was noted in the children across age.Conclusions Notably high uCys-C levels were observed in children with elevated proteinuria.Thus,uCys-C could be a potential biomarker in identifying communities at high risk of CKDu susceptibility.展开更多
Background:This study aimed to determine for the fi rst time the age-and gender-specific reference intervals for biomarkers of bone,metabolism,nutrition,and obesity in a nationally representative sample of the Iranian...Background:This study aimed to determine for the fi rst time the age-and gender-specific reference intervals for biomarkers of bone,metabolism,nutrition,and obesity in a nationally representative sample of the Iranian children and adolescents.Methods:We assessed the data of blood samples obtained from healthy Iranian children and adolescents,aged 7 to 19 years.The reference intervals of glucose,lipid profile,liver enzymes,zinc,copper,chromium,magnesium,and 25-hydroxy vitamin D[25(OH)D]were determined according to the Clinical&Laboratory Standards Institute C28-A3 guidelines.The reference intervals were partitioned using the Harris–Boyd method according to age and gender.Results:The study population consisted of 4800 school students(50%boys,mean age of 13.8 years).Twelve chemistry analyses were partitioned by age and gender,displaying the range of results between the 2.5th to 97.5th percentiles.Significant differences existed only between boys and girls at 18 to 19 years of age for low density lipoprotein-cholesterol.25(OH)D had the only reference interval that was similar to all age groups and both sexes.Conclusions:This study presented the first national database of reference intervals for a number of biochemical markers in Iranian children and adolescents.It is the fi rst report of its kind from the Middle East and North Africa.The fi ndings underscore the importance of providing reference intervals in different ethnicities and in various regions.展开更多
文摘Context: Vitamin E is a powerful antioxidant and plays an important role in human reproduction. However, micronutrient deficiency is a major public health problem, particularly in developing countries. This study aimed to establish reference intervals (RIs) for vitamin E in black Congolese people of childbearing age using an ELISA method to provide a reference for clinically assessing vitamin E status. Methods: A total of 127 healthy people between the ages of 20 and 42 who underwent check-ups were randomly selected for the study. ELISA method measured the level of vitamin E. The effect of gender on vitamin E level was assessed, and RI was established using a parametric approach. Results: Women showed significantly higher levels of vitamin E than men (p = 0.01). The RI of vitamin E in people of childbearing age was 3.71 to 13.72, 4.52 to 14.64, and 4.17 to 13.52 mg/L, respectively, for the whole population, women and men. Conclusion: Using an ELISA method, this study established RI for vitamin E in the black Congolese population of childbearing age. We also found that women had significantly higher vitamin E levels than men. The results could provide a scientific basis for interpreting vitamin status in people of childbearing age in our setting.
文摘BACKGROUND The indirect methods of reference intervals(RI)establishment based on data mining are utilized to overcome the ethical,practical challenges and the cost associated with the conventional direct approach.AIM To generate RIs for serum creatinine in children and adolescents using an indirect statistical tool.METHODS Data mining of the laboratory information system was performed for serum creatinine analyzed from birth to 17 years for both genders.The timeline was set at six years from January 2013 to December 2018.Microsoft Excel 2010 and an indirect algorithm developed by the German Society of Clinical Chemistry and Laboratory Medicine’s Working Group on Guide Limits were used for the data analysis.RESULTS Data were extracted from 96104 samples and after excluding multiple samples for the same individual,we calculated RIs for 21920 males and 14846 females,with stratification into six discrete age groups.CONCLUSION Serum creatinine dynamics varied significantly across gender and age groups.
文摘Objective:To demonstrate that serum follicle-stimulating hormone(FSH)in men rises with age,and to explore FSH reference intervals of age-related partitioning.Methods:Men aged 20-50 years(n=1190)underwent semen analysis according to World Health Organization(2010)methods.Serum was frozen prior to measurement of FSH by using the Siemens ADVIA Centaur®XP immunoassay system.FSH central 95%intervals after logarithmic transformation based on age were derived from 1037 normozoospermic men.These were then applied to oligozoospermic and azoospermic men.Men producing azoospermic semen samples were further classified as having non-obstructive azoospermia by clinical diagnostic criteria,including genetic analysis and surgical exploration.Results:Serum FSH in normozoospermic men increased with age(P<0.05),and reference intervals were determined with 10-year brackets:21-30 years[(1.0-8.2)IU/L],31-40 years[(1.4-9.5)IU/L],41-50 years[(1.9-12.0)IU/L].The proportion of oligozoospermic men with normal FSH concentrations was less than the normozoospermic men,which in turn was lower among azoospermic men(both P<0.01).The azoospermic men were further broken down according to the nature of the azoospermia as either obstructive or non-obstructive azoospermia,and 86.4%(38/44)men with non-obstructive azoospermia had elevated serum FSH concentrations whereas only 6.7%(1/15)men with obstructive azoospermia had high FSH levels,and this was significantly different(P<0.01).Conclusions:FSH concentrations increase in men between 20-50 years,and clinical interpretation of serum FSH results in men must be made by using age-based reference intervals.
基金supported by grants from National Science Foundation of China(grant No.81501839)Jilin Science and Technology Development Program(grant Nos.20160101091JC,20150414039GH)Norman Bethune Program of Jilin University(grant No.2012223).
文摘Background The development and growth of children influence values of liver function tests.This study aims to establish age-and gender-specific pediatric reference intervals of liver function among Han children in Changchun,China.Methods A total of 1394 healthy Han children,aged 2-14 years,were recruited from communities and schools with informed parental consent in Changchun.The levels of serum alanine aminotransferase(ALT),aspartate aminotransferase(AST),y-glutamyltransferase(GGT),alkaline phosphatase(ALP),total protein(TP),albumin(ALB),total bilirubin(TBIL)and direct bilirubin(DBIL)were measured on Hitachi 7600-210 automatic biochemical analyzer.The age-and gender-specific reference intervals were partitioned using Harris and Boyd's test and calculated using nonparametric rank method.The pediatric reference intervals were validated in five representative hospitals located in different areas in Changchun.Results All the analytes required some levels of age partitioning.Proteins(TP,ALB)and bilirubins(TBIL,DBIL)required no gender partitioning.In contrast,considerable gender partitioning was required for serum ALT,AST,GGT,and ALP.TP,TBIL,and DBIL showed steady increases,and AST showed apparent decreases over time,whereas ALT,GGT,ALP,and ALB demonstrated complex trends of change.ALT and GGT increased sharply in males from 11 to 14 years old.However,ALP declined in females from 13 to 14 years.All five laboratories passed the validation of reference intervals.Conclusions There were apparent age or gender variations of the reference intervals for liver function.When establishing pediatric reference intervals,partitioning according to age and gender is necessary.
基金This research was funded by the Accelerating Higher Education Expansion and Development(AHEAD)Operation of the Ministry of Higher Education funded by the World Bank(No.AHEAD DOR 02/40).
文摘Background Cystatin C(Cys-C)is an emerging biomarker of renal diseases and its clinical use,particularly for screening the communities affected by chronic kidney disease of unknown etiology(CKDu),is hindered due to the lack of reference intervals(RIs)for diverse ethnic and age groups.The present study aimed to define RIs for urinary Cys-C(uCys-C)for a healthy pediatric population in Sri Lanka and in turn compare the renal function of the residential children in CKDu endemic and non-endemic regions in Sri Lanka.Methods A cross-sectional study was conducted with 850 healthy children(10-17 years)from selected locations for reference interval establishment,while a total of 892 children were recruited for the comparative study.Urine samples were collected and analyzed for Cys-C,creatinine(Cr)and albumin.Cr-adjusted uCys-C levels were partitioned by age,and RIs were determined with quantile regression(2.5th,50th and 97.5th quantiles)at 90%confidence interval.Results The range of median RIs for uCys-C in healthy children was 45.94-64.44 ng/mg Cr for boys and 53.58-69.97 ng/mg Cr for girls.The median(interquartile range)uCys-C levels of children in the CKDu endemic and non-endemic regions were 58.18(21.8-141.9)and 58.31(23.9-155.3)ng/mg Cr with no significant difference(P=0.781).A significant variation of uCys-C was noted in the children across age.Conclusions Notably high uCys-C levels were observed in children with elevated proteinuria.Thus,uCys-C could be a potential biomarker in identifying communities at high risk of CKDu susceptibility.
基金This study was approved by the Isfahan University of Medical Sciences(No.293214).
文摘Background:This study aimed to determine for the fi rst time the age-and gender-specific reference intervals for biomarkers of bone,metabolism,nutrition,and obesity in a nationally representative sample of the Iranian children and adolescents.Methods:We assessed the data of blood samples obtained from healthy Iranian children and adolescents,aged 7 to 19 years.The reference intervals of glucose,lipid profile,liver enzymes,zinc,copper,chromium,magnesium,and 25-hydroxy vitamin D[25(OH)D]were determined according to the Clinical&Laboratory Standards Institute C28-A3 guidelines.The reference intervals were partitioned using the Harris–Boyd method according to age and gender.Results:The study population consisted of 4800 school students(50%boys,mean age of 13.8 years).Twelve chemistry analyses were partitioned by age and gender,displaying the range of results between the 2.5th to 97.5th percentiles.Significant differences existed only between boys and girls at 18 to 19 years of age for low density lipoprotein-cholesterol.25(OH)D had the only reference interval that was similar to all age groups and both sexes.Conclusions:This study presented the first national database of reference intervals for a number of biochemical markers in Iranian children and adolescents.It is the fi rst report of its kind from the Middle East and North Africa.The fi ndings underscore the importance of providing reference intervals in different ethnicities and in various regions.
