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Andrea Trevas Maciel-guerra - One of the best experts on this subject based on the ideXlab platform.

  • Androgens by immunoassay and mass spectrometry in children with 46,XY disorder of sex development.
    Endocrine connections, 2020
    Co-Authors: Letícia Ribeiro Oliveira, Carlos Alberto Longui, Guilherme Guaragna-filho, José Luiz Costa, Rafael Lanaro, David Antônio Silva, Maria Izabel Chiamolera, Maricilda Palandi De Mello, André Moreno Morcillo, Andrea Trevas Maciel-guerra
    Abstract:

    Objective Steroid measurement is a challenge in pediatric endocrinology. Currently, liquid chromatography with tandem mass spectrometry (LC-MS/MS) is considered a gold standard for this purpose. The aim of this study was to compare both LC-MS/MS and immunoassay (IA) for androgens before and after human Recombinant Chorionic Gonadotropin (r-hCG) stimulus in children with 46,XY Disorders of Sex Development (DSD). Methods Nineteen patients with 46,XY DSD were evaluated; all of them were prepubertal and non gonadectomized. Testosterone, dihydrotestosterone (DHT), dehydroepiandrosterone (DHEA) and androstenedione were measured by IA and LC-MS/MS before and 7 days after rhCG injection. The correlation between IA and LC-MS/MS was analysed by the intraclass correlation coefficient (ICC) and Spearman's rank correlation coefficient (SCC). For concordance analysis the Passing and Bablok (PB) regression and the Bland and Altman (BA) method were used. Results Testosterone showed excellent correlation (ICC = 0.960 and SCC = 0.964); DHT showed insignificant and moderate correlations as indicated by ICC (0.222) and SCC (0.631), respectively; DHEA showed moderate correlation (ICC = 0.585 and SCC = 0.716); and androstenedione had poor and moderate correlations in ICC (0.363) and SCC (0.735), respectively. Using the PB method, all hormones showed a linear correlation, but proportional and systematic concordance errors were detected for androstenedione, systematic errors for testosterone and no errors for DHEA and DHT. By the BA method, there was a trend of IA to overestimate testosterone and androstenedione and underestimate DHEA and DHT when compared to LC-MS/MS. Conclusion Traditional IA should be replaced by LC-MS/MS for the androgens measurement in prepubertal children whenever is possible.

  • Androgens by immunoassay and mass spectrometry in children with 46,XY disorder of sex development.
    Endocrine connections, 2020
    Co-Authors: Letícia Ribeiro Oliveira, Carlos Alberto Longui, Guilherme Guaragna-filho, José Luiz Costa, Rafael Lanaro, David Antônio Silva, Maria Izabel Chiamolera, Maricilda Palandi De Mello, André Moreno Morcillo, Andrea Trevas Maciel-guerra
    Abstract:

    Steroid measurement is a challenge in pediatric endocrinology. Currently, liquid chromatography with tandem mass spectrometry (LC-MS/MS) is considered a gold standard for this purpose. The aim of this study was to compare both LC-MS/MS and immunoassay (IA) for androgens before and after human Recombinant Chorionic Gonadotropin (rhCG) stimulus in children with 46,XY disorders of sex development (DSD). Nineteen patients with 46,XY DSD were evaluated; all of them were prepubertal and non-gonadectomized. Testosterone, dihydrotestosterone (DHT), DHEA and androstenedione were measured by IA and LC-MS/MS before and 7 days after rhCG injection. The correlation between IA and LC-MS/MS was analyzed by the intraclass correlation coefficient (ICC) and Spearman's rank correlation coefficient (SCC). For concordance analysis the Passing and Bablok (PB) regression and the Bland and Altman (BA) method were used. Testosterone showed excellent correlation (ICC = 0.960 and SCC = 0.964); DHT showed insignificant and moderate correlations as indicated by ICC (0.222) and SCC (0.631), respectively; DHEA showed moderate correlation (ICC = 0.585 and SCC = 0.716); and androstenedione had poor and moderate correlations in ICC (0.363) and SCC (0.735), respectively. Using the PB method, all hormones showed a linear correlation, but proportional and systematic concordance errors were detected for androstenedione, systematic errors for testosterone and no errors for DHEA and DHT. By the BA method, there was a trend of IA to overestimate testosterone and androstenedione and underestimate DHEA and DHT when compared to LC-MS/MS. Traditional IA should be replaced by LC-MS/MS for the androgens measurement in prepubertal children whenever is possible.

Iwona Bojar - One of the best experts on this subject based on the ideXlab platform.

  • Ovarian stimulation with human and Recombinant Gonadotropin – comparison of in vitro fertilization efficiency with use of time-lapse monitoring
    Reproductive Health, 2015
    Co-Authors: Artur Wdowiak, Iwona Bojar
    Abstract:

    Background Achieving pregnancy by in vitro fertilization (IVF) treatment depends on many factors, including the ovaries’ capacity and the efficiency of ovarian stimulation. The aim of this study was to assess the influence of ovarian stimulation with human and Recombinant Gonadotropin, as well as specific hormonal parameters, on the effectiveness of IVF and the dynamics of embryonic development. Methods The study involved 221 women aged 25–35 years in whom intracytoplasmic sperm injection was performed. The ovarian stimulation was carried out according to the short protocol: injections of Gonadotropin-releasing hormone analogue were followed by human (hFSH) and Recombinant (rFSH) follicle-stimulating hormone administration. The growth of embryos was monitored with a time-lapse system. Levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and anti-Müllerian hormone (AMH) were measured before ovarian stimulation, and levels of estradiol were assessed on the day of administration of Recombinant Chorionic Gonadotropin. Results Pregnancy was achieved in 77 women (group A) – 42 (54.55 %) of them were stimulated with hFSH and 35 (45.45 %) were stimulated with rFSH. Among the 144 women in whom pregnancy was not achieved (group B), hFSH was administered to 73 (50.69 %) women and rFSH to 71 (49.31 %) women. In both groups subsequent embryo development stages were usually noted earlier after hFSH stimulation than after rFSH stimulation. The average values of AMH, estradiol, and estradiol per >17 mm follicle were higher in group A; in turn, FSH and LH mean levels were higher in group B. ROC curve analysis showed no statistically significant differences between accuracy of using FSH and AMH levels to predict pregnancy after IVF. Conclusions The kind of Gonadotropin applied to stimulate ovaries impacts the dynamics of embryo development - in women stimulated with hFSH, subsequent development stages were usually observed earlier than in women treated with rFSH; however, there was no statistically significant difference in pregnancy rates between women who were hFSH stimulated and those who were rFSH stimulated. The mean estradiol level was higher in women who achieved pregnancy than in women in whom pregnancy was not achieved AMH and FSH have the greater impact on achieving pregnancy than other hormones, and the value of AMH and FSH in predicting pregnancy is similar.

  • Ovarian stimulation with human and Recombinant Gonadotropin – comparison of in vitro fertilization efficiency with use of time-lapse monitoring
    Reproductive health, 2015
    Co-Authors: Artur Wdowiak, Iwona Bojar
    Abstract:

    Achieving pregnancy by in vitro fertilization (IVF) treatment depends on many factors, including the ovaries’ capacity and the efficiency of ovarian stimulation. The aim of this study was to assess the influence of ovarian stimulation with human and Recombinant Gonadotropin, as well as specific hormonal parameters, on the effectiveness of IVF and the dynamics of embryonic development. The study involved 221 women aged 25–35 years in whom intracytoplasmic sperm injection was performed. The ovarian stimulation was carried out according to the short protocol: injections of Gonadotropin-releasing hormone analogue were followed by human (hFSH) and Recombinant (rFSH) follicle-stimulating hormone administration. The growth of embryos was monitored with a time-lapse system. Levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and anti-Mullerian hormone (AMH) were measured before ovarian stimulation, and levels of estradiol were assessed on the day of administration of Recombinant Chorionic Gonadotropin. Pregnancy was achieved in 77 women (group A) – 42 (54.55 %) of them were stimulated with hFSH and 35 (45.45 %) were stimulated with rFSH. Among the 144 women in whom pregnancy was not achieved (group B), hFSH was administered to 73 (50.69 %) women and rFSH to 71 (49.31 %) women. In both groups subsequent embryo development stages were usually noted earlier after hFSH stimulation than after rFSH stimulation. The average values of AMH, estradiol, and estradiol per >17 mm follicle were higher in group A; in turn, FSH and LH mean levels were higher in group B. ROC curve analysis showed no statistically significant differences between accuracy of using FSH and AMH levels to predict pregnancy after IVF. The kind of Gonadotropin applied to stimulate ovaries impacts the dynamics of embryo development - in women stimulated with hFSH, subsequent development stages were usually observed earlier than in women treated with rFSH; however, there was no statistically significant difference in pregnancy rates between women who were hFSH stimulated and those who were rFSH stimulated. The mean estradiol level was higher in women who achieved pregnancy than in women in whom pregnancy was not achieved AMH and FSH have the greater impact on achieving pregnancy than other hormones, and the value of AMH and FSH in predicting pregnancy is similar.

Letícia Ribeiro Oliveira - One of the best experts on this subject based on the ideXlab platform.

  • Androgens by immunoassay and mass spectrometry in children with 46,XY disorder of sex development.
    Endocrine connections, 2020
    Co-Authors: Letícia Ribeiro Oliveira, Carlos Alberto Longui, Guilherme Guaragna-filho, José Luiz Costa, Rafael Lanaro, David Antônio Silva, Maria Izabel Chiamolera, Maricilda Palandi De Mello, André Moreno Morcillo, Andrea Trevas Maciel-guerra
    Abstract:

    Objective Steroid measurement is a challenge in pediatric endocrinology. Currently, liquid chromatography with tandem mass spectrometry (LC-MS/MS) is considered a gold standard for this purpose. The aim of this study was to compare both LC-MS/MS and immunoassay (IA) for androgens before and after human Recombinant Chorionic Gonadotropin (r-hCG) stimulus in children with 46,XY Disorders of Sex Development (DSD). Methods Nineteen patients with 46,XY DSD were evaluated; all of them were prepubertal and non gonadectomized. Testosterone, dihydrotestosterone (DHT), dehydroepiandrosterone (DHEA) and androstenedione were measured by IA and LC-MS/MS before and 7 days after rhCG injection. The correlation between IA and LC-MS/MS was analysed by the intraclass correlation coefficient (ICC) and Spearman's rank correlation coefficient (SCC). For concordance analysis the Passing and Bablok (PB) regression and the Bland and Altman (BA) method were used. Results Testosterone showed excellent correlation (ICC = 0.960 and SCC = 0.964); DHT showed insignificant and moderate correlations as indicated by ICC (0.222) and SCC (0.631), respectively; DHEA showed moderate correlation (ICC = 0.585 and SCC = 0.716); and androstenedione had poor and moderate correlations in ICC (0.363) and SCC (0.735), respectively. Using the PB method, all hormones showed a linear correlation, but proportional and systematic concordance errors were detected for androstenedione, systematic errors for testosterone and no errors for DHEA and DHT. By the BA method, there was a trend of IA to overestimate testosterone and androstenedione and underestimate DHEA and DHT when compared to LC-MS/MS. Conclusion Traditional IA should be replaced by LC-MS/MS for the androgens measurement in prepubertal children whenever is possible.

  • Androgens by immunoassay and mass spectrometry in children with 46,XY disorder of sex development.
    Endocrine connections, 2020
    Co-Authors: Letícia Ribeiro Oliveira, Carlos Alberto Longui, Guilherme Guaragna-filho, José Luiz Costa, Rafael Lanaro, David Antônio Silva, Maria Izabel Chiamolera, Maricilda Palandi De Mello, André Moreno Morcillo, Andrea Trevas Maciel-guerra
    Abstract:

    Steroid measurement is a challenge in pediatric endocrinology. Currently, liquid chromatography with tandem mass spectrometry (LC-MS/MS) is considered a gold standard for this purpose. The aim of this study was to compare both LC-MS/MS and immunoassay (IA) for androgens before and after human Recombinant Chorionic Gonadotropin (rhCG) stimulus in children with 46,XY disorders of sex development (DSD). Nineteen patients with 46,XY DSD were evaluated; all of them were prepubertal and non-gonadectomized. Testosterone, dihydrotestosterone (DHT), DHEA and androstenedione were measured by IA and LC-MS/MS before and 7 days after rhCG injection. The correlation between IA and LC-MS/MS was analyzed by the intraclass correlation coefficient (ICC) and Spearman's rank correlation coefficient (SCC). For concordance analysis the Passing and Bablok (PB) regression and the Bland and Altman (BA) method were used. Testosterone showed excellent correlation (ICC = 0.960 and SCC = 0.964); DHT showed insignificant and moderate correlations as indicated by ICC (0.222) and SCC (0.631), respectively; DHEA showed moderate correlation (ICC = 0.585 and SCC = 0.716); and androstenedione had poor and moderate correlations in ICC (0.363) and SCC (0.735), respectively. Using the PB method, all hormones showed a linear correlation, but proportional and systematic concordance errors were detected for androstenedione, systematic errors for testosterone and no errors for DHEA and DHT. By the BA method, there was a trend of IA to overestimate testosterone and androstenedione and underestimate DHEA and DHT when compared to LC-MS/MS. Traditional IA should be replaced by LC-MS/MS for the androgens measurement in prepubertal children whenever is possible.

Artur Wdowiak - One of the best experts on this subject based on the ideXlab platform.

  • Ovarian stimulation with human and Recombinant Gonadotropin – comparison of in vitro fertilization efficiency with use of time-lapse monitoring
    Reproductive Health, 2015
    Co-Authors: Artur Wdowiak, Iwona Bojar
    Abstract:

    Background Achieving pregnancy by in vitro fertilization (IVF) treatment depends on many factors, including the ovaries’ capacity and the efficiency of ovarian stimulation. The aim of this study was to assess the influence of ovarian stimulation with human and Recombinant Gonadotropin, as well as specific hormonal parameters, on the effectiveness of IVF and the dynamics of embryonic development. Methods The study involved 221 women aged 25–35 years in whom intracytoplasmic sperm injection was performed. The ovarian stimulation was carried out according to the short protocol: injections of Gonadotropin-releasing hormone analogue were followed by human (hFSH) and Recombinant (rFSH) follicle-stimulating hormone administration. The growth of embryos was monitored with a time-lapse system. Levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and anti-Müllerian hormone (AMH) were measured before ovarian stimulation, and levels of estradiol were assessed on the day of administration of Recombinant Chorionic Gonadotropin. Results Pregnancy was achieved in 77 women (group A) – 42 (54.55 %) of them were stimulated with hFSH and 35 (45.45 %) were stimulated with rFSH. Among the 144 women in whom pregnancy was not achieved (group B), hFSH was administered to 73 (50.69 %) women and rFSH to 71 (49.31 %) women. In both groups subsequent embryo development stages were usually noted earlier after hFSH stimulation than after rFSH stimulation. The average values of AMH, estradiol, and estradiol per >17 mm follicle were higher in group A; in turn, FSH and LH mean levels were higher in group B. ROC curve analysis showed no statistically significant differences between accuracy of using FSH and AMH levels to predict pregnancy after IVF. Conclusions The kind of Gonadotropin applied to stimulate ovaries impacts the dynamics of embryo development - in women stimulated with hFSH, subsequent development stages were usually observed earlier than in women treated with rFSH; however, there was no statistically significant difference in pregnancy rates between women who were hFSH stimulated and those who were rFSH stimulated. The mean estradiol level was higher in women who achieved pregnancy than in women in whom pregnancy was not achieved AMH and FSH have the greater impact on achieving pregnancy than other hormones, and the value of AMH and FSH in predicting pregnancy is similar.

  • Ovarian stimulation with human and Recombinant Gonadotropin – comparison of in vitro fertilization efficiency with use of time-lapse monitoring
    Reproductive health, 2015
    Co-Authors: Artur Wdowiak, Iwona Bojar
    Abstract:

    Achieving pregnancy by in vitro fertilization (IVF) treatment depends on many factors, including the ovaries’ capacity and the efficiency of ovarian stimulation. The aim of this study was to assess the influence of ovarian stimulation with human and Recombinant Gonadotropin, as well as specific hormonal parameters, on the effectiveness of IVF and the dynamics of embryonic development. The study involved 221 women aged 25–35 years in whom intracytoplasmic sperm injection was performed. The ovarian stimulation was carried out according to the short protocol: injections of Gonadotropin-releasing hormone analogue were followed by human (hFSH) and Recombinant (rFSH) follicle-stimulating hormone administration. The growth of embryos was monitored with a time-lapse system. Levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and anti-Mullerian hormone (AMH) were measured before ovarian stimulation, and levels of estradiol were assessed on the day of administration of Recombinant Chorionic Gonadotropin. Pregnancy was achieved in 77 women (group A) – 42 (54.55 %) of them were stimulated with hFSH and 35 (45.45 %) were stimulated with rFSH. Among the 144 women in whom pregnancy was not achieved (group B), hFSH was administered to 73 (50.69 %) women and rFSH to 71 (49.31 %) women. In both groups subsequent embryo development stages were usually noted earlier after hFSH stimulation than after rFSH stimulation. The average values of AMH, estradiol, and estradiol per >17 mm follicle were higher in group A; in turn, FSH and LH mean levels were higher in group B. ROC curve analysis showed no statistically significant differences between accuracy of using FSH and AMH levels to predict pregnancy after IVF. The kind of Gonadotropin applied to stimulate ovaries impacts the dynamics of embryo development - in women stimulated with hFSH, subsequent development stages were usually observed earlier than in women treated with rFSH; however, there was no statistically significant difference in pregnancy rates between women who were hFSH stimulated and those who were rFSH stimulated. The mean estradiol level was higher in women who achieved pregnancy than in women in whom pregnancy was not achieved AMH and FSH have the greater impact on achieving pregnancy than other hormones, and the value of AMH and FSH in predicting pregnancy is similar.

T. Onaya - One of the best experts on this subject based on the ideXlab platform.

  • Recombinant thyrotropin stimulates cAMP formation in CHO-K1 cells expressing Recombinant Chorionic Gonadotropin receptor
    Biochemical and biophysical research communications, 1993
    Co-Authors: K. Gunji, T. Endo, M. Ohno, Takashi Minegishi, T. Onaya
    Abstract:

    Abstract Using CHO-K1 cells expressing rat thyrotropin-receptor (CHO-rTSH-R cells) or rat Chorionic Gonadotropin-receptor (CHO-rCG-R cells), we have examined their reactivity or cross-reactivity to Recombinant human thyrotropin (TSH) or human Chorionic Gonadotropin (hCG). TSH stimulated cAMP formation in CHO-rTSH-R cells dose-dependently, and the maximum response was obtained at 1 mIU/ml. hCG also increased cAMP in the cells from 10 4 mIU/ml, and the maximum stimulation was observed at 10 6 mIU/ml. 10 7 mIU of hCG had the same potency with 1 mIU of TSH to rTSH-R. On the other hand, 10 −1 mIU/ml of hCG increased cAMP content in CHO-rCG-R cells and reached the maximum level at 10 2 mIU/ml. TSH also showed the stimulatory activity to CHO-rCG-R cells. It increased cAMP formation in CHO-rCG-R cells dose-dependently from 10 mIU/ml to 10 3 mIU/ml. Thirty mIU of TSH was calculated to be equivalent to 1 mIU of hCG to CG-R. These results indicate that TSH and hCG cross-react each other with rTSH-R or rCG-R.