The Experts below are selected from a list of 6 Experts worldwide ranked by ideXlab platform

Irving Boime - One of the best experts on this subject based on the ideXlab platform.

  • design of a long acting Follitropin agonist by fusing the c terminal sequence of the chorionic gonadotropin Beta Subunit to the Follitropin Beta Subunit
    Proceedings of the National Academy of Sciences of the United States of America, 1992
    Co-Authors: F A Fares, Nobuhiko Suganuma, Kana Nishimori, Philip S. Lapolt, Aaron J. W. Hsueh, Irving Boime
    Abstract:

    Abstract Follitropin (FSH) is a pituitary glycoprotein hormone that is essential for the development of ovarian follicles and testicular seminiferous tubules. FSH is used clinically to stimulate follicular maturation for in vitro fertilization and treatment of anovulatory women. One issue regarding the clinical use of FSH is its short half-life in the circulation. To address this point, we constructed chimeric genes containing the sequence encoding the C-terminal peptide of the chorionic gonadotropin Beta Subunit (CG Beta) fused to the translated sequence of the human FSH Beta Subunit (FSH Beta). This region of CG Beta is important for maintaining the prolonged plasma half-life of human CG dimer. The presence of the C-terminal peptide sequence did not significantly affect assembly of FSH Beta with the alpha Subunit or secretion of the dimer. In vitro receptor binding and steroidogenic activity of dimer bearing the FSH Beta-C-terminal peptide chimera were the same as wild-type FSH. However, both the in vivo potency and half-life in circulation of the dimer bearing either one or two C-terminal peptide units were enhanced. Dimers containing FSH Beta-CG Beta chimeras could serve as potent FSH agonists for clinical use, and the present strategy may have wide applications for enhancing the in vivo half-life of diverse proteins.

Krishna Chatterjee - One of the best experts on this subject based on the ideXlab platform.

  • Follitropin fsh deficiency in an infertile male due to fshBeta gene mutation a syndrome of normal puberty and virilization but underdeveloped testicles with azoospermia low fsh but high lutropin and normal serum testosterone concentrations
    Clinical Chemistry and Laboratory Medicine, 1998
    Co-Authors: Goran Lindstedt, Ernst Nystrom, Clare Matthews, Ingrid Ernest, Per Olof Janson, Krishna Chatterjee
    Abstract:

    We studied a man who sought medical attention at age 28 years because of infertility in both his first and second marriages. His sexual development appeared to have been normal, with normal puberty and virilization, and normal libido and sexual potency. At examination, his testicles were small and soft; otherwise he had a normal physical appearance. Evaluations revealed azoospermia, undetectable in serum before and after 100 microg of intravenously administered gonadotrophin releasing hormone, but moderately elevated lutropin concentration with a brisk rise after gonadotrophin releasing hormone. The alpha Subunit concentration was normal before and after gonadotrophin releasing hormone; that of inhibin B was very low. Analysis of the Follitropin Beta gene, exon 3, revealed a Cys82 --> Arg mutation (TGT --> CGT). Judging from studies of the biosynthesis of the chorionic gonadotrophin Beta Subunit one may conclude that inability to form the first intramolecular disulphide bond in the Follitropin Beta Subunit results in an abnormal tertiary structure during Follitropin Beta biosynthesis with extensive intracellular degradation of the products, inability to associate with the alpha Subunit and defective glycosylation, as well as inability to form a biologically active hormone. This first male case of Follitropin deficiency thus defines a new syndrome of male infertility.

F A Fares - One of the best experts on this subject based on the ideXlab platform.

  • design of a long acting Follitropin agonist by fusing the c terminal sequence of the chorionic gonadotropin Beta Subunit to the Follitropin Beta Subunit
    Proceedings of the National Academy of Sciences of the United States of America, 1992
    Co-Authors: F A Fares, Nobuhiko Suganuma, Kana Nishimori, Philip S. Lapolt, Aaron J. W. Hsueh, Irving Boime
    Abstract:

    Abstract Follitropin (FSH) is a pituitary glycoprotein hormone that is essential for the development of ovarian follicles and testicular seminiferous tubules. FSH is used clinically to stimulate follicular maturation for in vitro fertilization and treatment of anovulatory women. One issue regarding the clinical use of FSH is its short half-life in the circulation. To address this point, we constructed chimeric genes containing the sequence encoding the C-terminal peptide of the chorionic gonadotropin Beta Subunit (CG Beta) fused to the translated sequence of the human FSH Beta Subunit (FSH Beta). This region of CG Beta is important for maintaining the prolonged plasma half-life of human CG dimer. The presence of the C-terminal peptide sequence did not significantly affect assembly of FSH Beta with the alpha Subunit or secretion of the dimer. In vitro receptor binding and steroidogenic activity of dimer bearing the FSH Beta-C-terminal peptide chimera were the same as wild-type FSH. However, both the in vivo potency and half-life in circulation of the dimer bearing either one or two C-terminal peptide units were enhanced. Dimers containing FSH Beta-CG Beta chimeras could serve as potent FSH agonists for clinical use, and the present strategy may have wide applications for enhancing the in vivo half-life of diverse proteins.

Goran Lindstedt - One of the best experts on this subject based on the ideXlab platform.

  • Follitropin fsh deficiency in an infertile male due to fshBeta gene mutation a syndrome of normal puberty and virilization but underdeveloped testicles with azoospermia low fsh but high lutropin and normal serum testosterone concentrations
    Clinical Chemistry and Laboratory Medicine, 1998
    Co-Authors: Goran Lindstedt, Ernst Nystrom, Clare Matthews, Ingrid Ernest, Per Olof Janson, Krishna Chatterjee
    Abstract:

    We studied a man who sought medical attention at age 28 years because of infertility in both his first and second marriages. His sexual development appeared to have been normal, with normal puberty and virilization, and normal libido and sexual potency. At examination, his testicles were small and soft; otherwise he had a normal physical appearance. Evaluations revealed azoospermia, undetectable in serum before and after 100 microg of intravenously administered gonadotrophin releasing hormone, but moderately elevated lutropin concentration with a brisk rise after gonadotrophin releasing hormone. The alpha Subunit concentration was normal before and after gonadotrophin releasing hormone; that of inhibin B was very low. Analysis of the Follitropin Beta gene, exon 3, revealed a Cys82 --> Arg mutation (TGT --> CGT). Judging from studies of the biosynthesis of the chorionic gonadotrophin Beta Subunit one may conclude that inability to form the first intramolecular disulphide bond in the Follitropin Beta Subunit results in an abnormal tertiary structure during Follitropin Beta biosynthesis with extensive intracellular degradation of the products, inability to associate with the alpha Subunit and defective glycosylation, as well as inability to form a biologically active hormone. This first male case of Follitropin deficiency thus defines a new syndrome of male infertility.

Nobuhiko Suganuma - One of the best experts on this subject based on the ideXlab platform.

  • design of a long acting Follitropin agonist by fusing the c terminal sequence of the chorionic gonadotropin Beta Subunit to the Follitropin Beta Subunit
    Proceedings of the National Academy of Sciences of the United States of America, 1992
    Co-Authors: F A Fares, Nobuhiko Suganuma, Kana Nishimori, Philip S. Lapolt, Aaron J. W. Hsueh, Irving Boime
    Abstract:

    Abstract Follitropin (FSH) is a pituitary glycoprotein hormone that is essential for the development of ovarian follicles and testicular seminiferous tubules. FSH is used clinically to stimulate follicular maturation for in vitro fertilization and treatment of anovulatory women. One issue regarding the clinical use of FSH is its short half-life in the circulation. To address this point, we constructed chimeric genes containing the sequence encoding the C-terminal peptide of the chorionic gonadotropin Beta Subunit (CG Beta) fused to the translated sequence of the human FSH Beta Subunit (FSH Beta). This region of CG Beta is important for maintaining the prolonged plasma half-life of human CG dimer. The presence of the C-terminal peptide sequence did not significantly affect assembly of FSH Beta with the alpha Subunit or secretion of the dimer. In vitro receptor binding and steroidogenic activity of dimer bearing the FSH Beta-C-terminal peptide chimera were the same as wild-type FSH. However, both the in vivo potency and half-life in circulation of the dimer bearing either one or two C-terminal peptide units were enhanced. Dimers containing FSH Beta-CG Beta chimeras could serve as potent FSH agonists for clinical use, and the present strategy may have wide applications for enhancing the in vivo half-life of diverse proteins.