• Title/Summary/Keyword: reproductive development

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Rhox in mammalian reproduction and development

  • Lee, Sang-Eun;Lee, Su-Yeon;Lee, Kyung-Ah
    • Clinical and Experimental Reproductive Medicine
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    • v.40 no.3
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    • pp.107-114
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    • 2013
  • Homeobox genes play essential roles in embryonic development and reproduction. Recently, a large cluster of homeobox genes, reproductive homeobox genes on the X chromosome (Rhox) genes, was discovered as three gene clusters, ${\alpha}$, ${\beta}$, and ${\gamma}$ in mice. It was found that Rhox genes were selectively expressed in reproduction-associated tissues, such as those of the testes, epididymis, ovaries, and placenta. Hence, it was proposed that Rhox genes are important for regulating various reproductive features, especially gametogenesis in male as well as in female mammals. It was first determined that 12 Rhox genes are clustered into ${\alpha}$ (Rhox1-4), ${\beta}$ (Rhox5-9), and ${\gamma}$ (Rhox10-12) subclusters, and recently Rhox13 has also been found. At present, 33 Rhox genes have been identified in the mouse genome, 11 in the rat, and three in the human. Rhox genes are also responsible for embryonic development, with considerable amounts of Rhox expression in trophoblasts, placenta tissue, embryonic stem cells, and primordial germ cells. In this article we summarized the current understanding of Rhox family genes involved in reproduction and embryonic development and elucidated a previously unreported cell-specific expression in ovarian cells.

Arsenic Toxicity in Male Reproduction and Development

  • Kim, Yoon-Jae;Kim, Jong-Min
    • Development and Reproduction
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    • v.19 no.4
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    • pp.167-180
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    • 2015
  • Arsenic is a toxic metalloid that exists ubiquitously in the environment, and affects global health problems due to its carcinogenicity. In most populations, the main source of arsenic exposure is the drinking water. In drinking water, chronic exposure to arsenic is associated with increased risks of various cancers including those of skin, lung, bladder, and liver, as well as numerous other non-cancer diseases including gastrointestinal and cardiovascular diseases, diabetes, and neurologic and cognitive problems. Recent emerging evidences suggest that arsenic exposure affects the reproductive and developmental toxicity. Prenatal exposure to inorganic arsenic causes adverse pregnancy outcomes and children's health problems. Some epidemiological studies have reported that arsenic exposure induces premature delivery, spontaneous abortion, and stillbirth. In animal studies, inorganic arsenic also causes fetal malformation, growth retardation, and fetal death. These toxic effects depend on dose, route and gestation periods of arsenic exposure. In males, inorganic arsenic causes reproductive dysfunctions including reductions of the testis weights, accessory sex organs weights, and epididymal sperm counts. In addition, inorganic arsenic exposure also induces alterations of spermatogenesis, reductions of testosterone and gonadotrophins, and disruptions of steroidogenesis. However, the reproductive and developmental problems following arsenic exposure are poorly understood, and the molecular mechanism of arsenic-induced reproductive toxicity remains unclear. Thus, we further investigated several possible mechanisms underlying arsenic-induced reproductive toxicity.

Do family values and reproductive health knowledge influence reproductive health-promoting behaviors in married women? A cross-sectional survey (기혼여성의 가족가치관, 생식건강지식이 생식건강증진행위에 미치는 영향)

  • Sun Jeong Yun;Hye Young Kim
    • Women's Health Nursing
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    • v.28 no.4
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    • pp.286-295
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    • 2022
  • Purpose: Based on the World Health Organization framework on reproductive health, this descriptive correlational study investigated the factors affecting reproductive health-promoting behaviors of married women, with a focus on family values and reproductive health knowledge. Methods: A cross-sectional survey was conducted on 170 married women between the ages of 25 and 49 years living in Daegu, Korea. The general and reproductive health characteristics, family values, and reproductive health knowledge of married women were identified, as well as factors affecting reproductive health-promoting behaviors. A questionnaire survey was administered to investigate the impact of various factors on reproductive health-promoting behaviors. Results: Positive correlations were shown for family values (r=.78, p<.001) and reproductive health knowledge (r=.55, p<.001). Family values (β=.35, p<.001) and reproductive health knowledge (β=.24, p<.001) were identified as factors influencing reproductive health-promoting behaviors. According to the regression model, the explanatory power of factors affecting reproductive health-promoting behaviors among married women was 51.2%. Conclusion: A history of reproductive diseases, family values, and reproductive health knowledge were identified as factors influencing reproductive health-promoting behaviors. These results will provide basic data for the development of a reproductive health-promoting program, including a positive approach to reproductive health among married women, and will serve as a basis for further research on intervention strategies.

Sexual Maturity and Reproductive Cycle of Starry Flounder Platichthys stellatus Cultured in Indoor Tank (실내 사육한 강도다리 Platichthys stellatus의 성성숙과 생식주기)

  • Lim, Han-Kyu;Byun, Soon-Gyu;Lee, Jong-Ha;Park, Sang-Un;Kim, Yi-Cheong;Han, Hyoung-Kyun;Min, Byung-Hwa;Lee, Bea-Yik
    • Journal of Aquaculture
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    • v.20 no.4
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    • pp.212-218
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    • 2007
  • Reproductive biology (sexual maturity and reproductive cycle) of starry flounder Platichthys stellatus were examined by histological methods. From March 2004 to February 2005, 144 females and males were sampled. Gonadosomatic index (GSI) of female and male were peaked in May and February, respectively. Monthly changes of hepatosomotic index (HSI) showed a negative correlationwith those of the GSI. Changes of condition factor (CF) in female were correlated with gonad maturation, while that of male were no difference all the year round. Based on monthly GSI and gonadal development the reproductive cycle of starry flounder could be divided into four stages: growing stage (September to November), maturation stage (September to February), ripe and spent stage (March to May), and recovery and resting stage (June to August). Biological minimum size of female was 1,074 g. The relationship between fecundity (F) and body weight (BW) of the fish was expressed as $F\;=\;455.86BW^{1.2006}$.

Annual Reproductive Cycle of Acheilognathus majusculus, a Korean Endemic Species

  • Lim, Jin-Yeong;Lee, Won-Kyo
    • Development and Reproduction
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    • v.21 no.3
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    • pp.297-305
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    • 2017
  • An experiment was conducted to investigate the annual reproductive cycle of a Korean endemic species, Acheilognathus majusculus, from Jeokseong-myeon located in Seomjin River. The reproductive cycle is examined histologically regarding water temperature and day length of the habitat, the gonadosomatic index (GSI), the female ovipositor length index (OLI), monthly variation in egg diameter distribution, and developmental characteristics of female and male gonads. The maximum GSI was found in $19.21{\pm}2.32$ and $6.90{\pm}0.53$ for female and male respectively when water temperature ($14^{\circ}C$) and day length (11.1hr) began to rise. On the other hand, the minimum level was reached during August ($1.87{\pm}0.67$ for female and $0.88{\pm}0.50$ for male). No samples represent with measurable ovipositor between September and November, while the longest ovipositor length index was in April ($79.68{\pm}4.69%$). We compared and calculated the stages of testis and ovary development process in order to determine the germ cell development characteristics and the reproductive cycle. According to the result, we classified the female Acheilognathus majusculus reproductive cycle into four stages: Ripe (April) and spawning phase (May to June), degenerative phase (July), growing phase (August to December), and mature phase (January to March). The annual reproductive cycle of male Acheilognathus majusculus was categorized into five stages viz. Ripe and spawning phase (May to June), degenerative phase (July to August), resting phase (September to November), growing phase (December to February), and mature phase (March to April).

Use of Reproductive Health Information among University Undergraduates in Ogun State, Nigeria

  • Adeyoyin, Samuel Olu
    • International Journal of Knowledge Content Development & Technology
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    • v.7 no.3
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    • pp.49-65
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    • 2017
  • Young adults bear a higher risk of reproductive health problems than adults. Cases of unwanted pregnancies and their attendant complications reportedly rank among the highest in Africa. This study therefore investigates reproductive health and use of health information among university undergraduates in Nigeria. Correlational research design was adopted using descriptive survey method. Questionnaire was designed and used as survey instrument. The study used 25% of 6,978 undergraduate students from government and private universities in Abeokuta, Ogun State between 16-24 years old from each of the 35 departments that made up 8 colleges in the two universities. A total number of 1,745 copies of questionnaire were administered to the respondents out of which 1,500 copies were filled completely and retrieved making the response rate to be 86.95%. The findings of this study show that friends, parents and relatives were the closest sources of health information the respondents have used for reproductive health purposes. Utilisation of health information through information resources was effective. The study also concludes that cultural value, level of education and unfriendly attitude of health officials were parts of the major problems confronting effective utilization of reproductive health information among young adults in Nigeria.

Reproductive Cycle of Chameleon Goby, Tridentiger trigonocephalus in the Southern Coastal Waters of Korea

  • Hwang, In Joon;Baek, Hea Ja
    • Development and Reproduction
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    • v.17 no.4
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    • pp.353-361
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    • 2013
  • The objective of this study was to characterize the reproductive cycle of the chameleon goby, T. trigonocephalus. Gonadal development was investigated using a histological method. Specimens were collected monthly, from April 2009 to March 2010. The gonadosomatic index (GSI) of females began to increase in April, reaching the maximum in May, and declined sharply in August. In males, the GSI began to increase in April and reaching the maximum in July. The annual reproductive cycle of T. trigonocephalus can be divided into four successive stages in females: the growing (November-March), maturing (April-May), ripe and spawning (June-July), and recovery (August-October) stages. Males passed through growing (November-March), maturing (April-June), ripe and spermiation (July-August), and recovery (September-October) stages. These results indicate the spawning season is from June to July. The relationship between fecundity (Fc) and body length (BL) was $Fc=86.1511BL^{2.6506}$. Fecundity was ranged from 3,448-9,654 eggs in a BL of 4.8-7.2 cm and it was increased as BL increased.

Gonadal Development and Reproductive Cycle of Sea Hare Aplysia kurodai in Jeju Coastal Waters

  • Lee, Chi-Hoon;Kaang, Bong-Kiun;Lee, Young-Don
    • Development and Reproduction
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    • v.15 no.3
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    • pp.257-263
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    • 2011
  • Gonadal development and reproductive cycle of Aplysia kurodai inhabiting the coastal waters of Jeju Island, Korea were investigated based on monthly changes of gonadosomatic index, gametogenesis, and developmental phases of ovotestis. A. kurodai was simultaneous hermaphrodite; the ovotestis generally embedded in the posterior dorsal surface of the brownish digestive gland. The ovotestis is composed of a large number of follicles, and both oocytes and sperm are produced in the same follicles. In the sampling periods, the adult A. kurodai population have characteristic of seasonal pattern present during only 10 months. The reproductive cycle can be grouped into the following successive stages in the ovary: inactive (December to February), active (December to April), mature and spawning (April to September). The gonadal development of A. kurodai coincided with rising temperature, and spawning occurred from April to September, when the temperature was high. The histological observations of the ovotestis suggested that this species have a single spawning season that extend over six months.