The Experts below are selected from a list of 39 Experts worldwide ranked by ideXlab platform
Alice F Tarantal - One of the best experts on this subject based on the ideXlab platform.
-
effects of exogenous estrogenic agents on pubertal growth and reproductive system maturation in female rhesus monkeys
Toxicological Sciences, 2003Co-Authors: Mari S Golub, Casey Hogrefe, Stacey L Germann, Bill L Lasley, Kala Natarajan, Alice F TarantalAbstract:Concern has been raised that environmental contaminants with estrogenic properties can alter normal Sexual maturation. Monkeys, like humans, undergo a long and complex period of development during adolescence, which makes them important models for understanding exogenous estrogen effects during this period. This study examined the consequences of treatment with estrogenic agents (methoxychlor, MXC, 25 and 50 mg/kg/day; diethylstilbestrol, DES, 0.5 mg/kg/day) given in the peripubertal period (6 months before and after the expected age at menarche) to female rhesus monkeys. These treatments increased estrogen activity of serum as determined with an in vitro estrogen receptor alpha (ERa) transcription assay. DES completely suppressed adolescent growth (weight and height) and menses in a reversible manner; smaller effects of MXC on the timing of growth and menarche were also detected. Both DES and MXC led to premature emergence of a Secondary Sex Characteristic, reddening and swelling of skin, but retarded growth of the nipple. As evaluated by ultrasound after an 8-month recovery period, uterine size was not affected by exogenous estrogen, but there was some indication of increased incidence of ovarian cysts/masses in MXC- and DES-treated groups. Ovarian cyclicity, as reflected in urinary hormone metabolites, demonstrated shorter follicular stages in the MXC-treated monkeys. In conclusion, the data indicate that DES had a striking effect on adolescent maturation and that the estrogenic pesticide MXC also altered development during this period. The pattern of effects across agents and doses may be based on specifics of estrogenic action, such as relative ERalpha and ERbeta binding and activation. Long-term consequences of this disruption of pubertal development are being studied in this cohort of monkeys as adults.
Atsuo Iida - One of the best experts on this subject based on the ideXlab platform.
-
Male-specific asymmetric curvature of anal fin in a viviparous teleost, Xenotoca eiseni.
Zoology (Jena Germany), 2019Co-Authors: Atsuo IidaAbstract:Abstract Xenotoca eiseni is a viviparous teleost from the family Goodeidae. Internal fertilization occurs in this species; therefore, the male fish must transfer their sperm to the females. To this end, the males use their anal fins as external genitalia during mating. However, in goodeid species, there are a few reports of anal fin modifications functioning as genitalia. In the present study, I describe a male-specific lateral curvature with fin robe thickening on the two most posterior rays of the anal fin of X. eiseni. Morphological and behavioral analyses suggested that the lateral curvature provides a directional preference for coupling of male X. eiseni. The modification appears to be a male Secondary Sex Characteristic. Other goodeid species Xenotoca melanosoma and Chapalichthys pardalis also possess the lateral curvature, but without robe thickening. Furthermore, Zoogoneticus quitzeoensis exhibited only curvature structure either smaller than those of other species or absent. Therefore, the anal fin curvature may not necessarily be used for internal fertilization in all species investigated in this study. However, it is still possible that it provides novel advantages during mating in certain goodeid species.
Mari S Golub - One of the best experts on this subject based on the ideXlab platform.
-
effects of exogenous estrogenic agents on pubertal growth and reproductive system maturation in female rhesus monkeys
Toxicological Sciences, 2003Co-Authors: Mari S Golub, Casey Hogrefe, Stacey L Germann, Bill L Lasley, Kala Natarajan, Alice F TarantalAbstract:Concern has been raised that environmental contaminants with estrogenic properties can alter normal Sexual maturation. Monkeys, like humans, undergo a long and complex period of development during adolescence, which makes them important models for understanding exogenous estrogen effects during this period. This study examined the consequences of treatment with estrogenic agents (methoxychlor, MXC, 25 and 50 mg/kg/day; diethylstilbestrol, DES, 0.5 mg/kg/day) given in the peripubertal period (6 months before and after the expected age at menarche) to female rhesus monkeys. These treatments increased estrogen activity of serum as determined with an in vitro estrogen receptor alpha (ERa) transcription assay. DES completely suppressed adolescent growth (weight and height) and menses in a reversible manner; smaller effects of MXC on the timing of growth and menarche were also detected. Both DES and MXC led to premature emergence of a Secondary Sex Characteristic, reddening and swelling of skin, but retarded growth of the nipple. As evaluated by ultrasound after an 8-month recovery period, uterine size was not affected by exogenous estrogen, but there was some indication of increased incidence of ovarian cysts/masses in MXC- and DES-treated groups. Ovarian cyclicity, as reflected in urinary hormone metabolites, demonstrated shorter follicular stages in the MXC-treated monkeys. In conclusion, the data indicate that DES had a striking effect on adolescent maturation and that the estrogenic pesticide MXC also altered development during this period. The pattern of effects across agents and doses may be based on specifics of estrogenic action, such as relative ERalpha and ERbeta binding and activation. Long-term consequences of this disruption of pubertal development are being studied in this cohort of monkeys as adults.
Seishu Abe - One of the best experts on this subject based on the ideXlab platform.
-
Dog-bite injuries to the breast in children: deformities to Secondary Sex Characteristics and their repair in an extended follow-up.
Annals of plastic surgery, 1999Co-Authors: Nariaki Miyata, Seishu AbeAbstract:Injuries from dog bites are not uncommon among children. However, the site of the wound is rarely on the breast. The authors report two cases of nipple-areolar injuries caused by dog bites. The affected children were followed during the development of Secondary Sex Characteristics. In one child, this follow-up period was more than 10 years. In treating such wounds to the breast, subsequent growth of the nipple-areolar complex should be considered, particularly in girls because of the area's importance as a Secondary Sex Characteristic.
Casey Hogrefe - One of the best experts on this subject based on the ideXlab platform.
-
effects of exogenous estrogenic agents on pubertal growth and reproductive system maturation in female rhesus monkeys
Toxicological Sciences, 2003Co-Authors: Mari S Golub, Casey Hogrefe, Stacey L Germann, Bill L Lasley, Kala Natarajan, Alice F TarantalAbstract:Concern has been raised that environmental contaminants with estrogenic properties can alter normal Sexual maturation. Monkeys, like humans, undergo a long and complex period of development during adolescence, which makes them important models for understanding exogenous estrogen effects during this period. This study examined the consequences of treatment with estrogenic agents (methoxychlor, MXC, 25 and 50 mg/kg/day; diethylstilbestrol, DES, 0.5 mg/kg/day) given in the peripubertal period (6 months before and after the expected age at menarche) to female rhesus monkeys. These treatments increased estrogen activity of serum as determined with an in vitro estrogen receptor alpha (ERa) transcription assay. DES completely suppressed adolescent growth (weight and height) and menses in a reversible manner; smaller effects of MXC on the timing of growth and menarche were also detected. Both DES and MXC led to premature emergence of a Secondary Sex Characteristic, reddening and swelling of skin, but retarded growth of the nipple. As evaluated by ultrasound after an 8-month recovery period, uterine size was not affected by exogenous estrogen, but there was some indication of increased incidence of ovarian cysts/masses in MXC- and DES-treated groups. Ovarian cyclicity, as reflected in urinary hormone metabolites, demonstrated shorter follicular stages in the MXC-treated monkeys. In conclusion, the data indicate that DES had a striking effect on adolescent maturation and that the estrogenic pesticide MXC also altered development during this period. The pattern of effects across agents and doses may be based on specifics of estrogenic action, such as relative ERalpha and ERbeta binding and activation. Long-term consequences of this disruption of pubertal development are being studied in this cohort of monkeys as adults.