Guppies( Poecilia reticulata) are considered a candidate model species for the identification and testing of endocrine-disrupting chemicals. Male guppies may be used to address the challenge of making potential linkag...Guppies( Poecilia reticulata) are considered a candidate model species for the identification and testing of endocrine-disrupting chemicals. Male guppies may be used to address the challenge of making potential linkages between alterations of biomarkers, both at the cellular and organ level, and adverse outcomes. In the present study, a predictive relationship between sex characteristics and reproductive output was observed in male guppies that underwent a long-term toxicity test with 0.5 μg/L 17 β-estradiol administered during the juvenile period. Radioimmunoassay and western blot analyses demonstrated that 17 β-estradiol exposure caused a significant increase in testicular 17 β-estradiol levels as well as the induction of exposure biomarkers, namely hepatic vitellogenin. Exposure to 17 β-estradiol also caused a significant decrease in testosterone levels, which consequently reduced the gonadosomatic index, sperm counts, and the coloration index. These changes of male sexual characteristics further translated into adverse influences on reproduction, as measured by a decrease in offspring production and survival rate. Our results suggest that the above-mentioned sexual characteristics of male guppies may be considered potential in vivo biomarkers of estrogen effects on reproduction.展开更多
Introduction: Early puberty is defined by development of secondary sexual characteristics before the age of 8 years in girls and 9 years in boys. In the West, one in five children out of 100,000 is concerned. Little i...Introduction: Early puberty is defined by development of secondary sexual characteristics before the age of 8 years in girls and 9 years in boys. In the West, one in five children out of 100,000 is concerned. Little information on sub-Saharan African patients exists concerning this pathology. Objective: To determine the etiology and clinical characteristics of early puberty in a cohort of Ivorian children. Methods: We conducted a cross-sectional study between 2015 and 2017 in children admitted to early puberty in the unique Endocrinology Service of the country. The epidemiology and clinical characteristics were assessed. Results: The eight patients involved were all females. Their mean age at diagnosis was 7 years and 3 months and the mean age of first symptoms begun at 5 years and 6 months. Seven patients had a central precocious puberty (CPP) including five cases of idiopathic CPP (ICPP) treated by (GnRH agonist) and two cases with secondary precocious puberty (SPP). One of them has a hypothalamic hamartoma and the other a sequelae of encephalopathy. The last case had a peripheral precocious puberty (PPP) causes by ovarian dystrophy. Conclusion: Our results confirm the predominance of idiopathic central precocious puberty particularly in girls.展开更多
基金Supported by the National Natural Science Foundation of China(No.31202001)the Natural Science Foundation of Shandong Province,China(No.ZR2012CQ010)
文摘Guppies( Poecilia reticulata) are considered a candidate model species for the identification and testing of endocrine-disrupting chemicals. Male guppies may be used to address the challenge of making potential linkages between alterations of biomarkers, both at the cellular and organ level, and adverse outcomes. In the present study, a predictive relationship between sex characteristics and reproductive output was observed in male guppies that underwent a long-term toxicity test with 0.5 μg/L 17 β-estradiol administered during the juvenile period. Radioimmunoassay and western blot analyses demonstrated that 17 β-estradiol exposure caused a significant increase in testicular 17 β-estradiol levels as well as the induction of exposure biomarkers, namely hepatic vitellogenin. Exposure to 17 β-estradiol also caused a significant decrease in testosterone levels, which consequently reduced the gonadosomatic index, sperm counts, and the coloration index. These changes of male sexual characteristics further translated into adverse influences on reproduction, as measured by a decrease in offspring production and survival rate. Our results suggest that the above-mentioned sexual characteristics of male guppies may be considered potential in vivo biomarkers of estrogen effects on reproduction.
文摘Introduction: Early puberty is defined by development of secondary sexual characteristics before the age of 8 years in girls and 9 years in boys. In the West, one in five children out of 100,000 is concerned. Little information on sub-Saharan African patients exists concerning this pathology. Objective: To determine the etiology and clinical characteristics of early puberty in a cohort of Ivorian children. Methods: We conducted a cross-sectional study between 2015 and 2017 in children admitted to early puberty in the unique Endocrinology Service of the country. The epidemiology and clinical characteristics were assessed. Results: The eight patients involved were all females. Their mean age at diagnosis was 7 years and 3 months and the mean age of first symptoms begun at 5 years and 6 months. Seven patients had a central precocious puberty (CPP) including five cases of idiopathic CPP (ICPP) treated by (GnRH agonist) and two cases with secondary precocious puberty (SPP). One of them has a hypothalamic hamartoma and the other a sequelae of encephalopathy. The last case had a peripheral precocious puberty (PPP) causes by ovarian dystrophy. Conclusion: Our results confirm the predominance of idiopathic central precocious puberty particularly in girls.
