• 한국독성학회:학술대회논문집
• /
• 한국독성학회 2003년도 춘계학술대회 논문집
• /
• pp.68-69
• /
• 2003

Tributyltin (TBT) used world-wide in antifouling paints for ships is a widespread environmental pollutant and cause reproductive organs atrophy in rodents. At low doses, antiproliferative modes of action have been shown to be involved, whereas at higher doses apoptosis seems to be the mechanism of toxicity in reproductive organs by TBT. (omitted)

• Journal of Ginseng Research
• /
• 제48권3호
• /
• pp.333-340
• /
• 2024

Background: Korean red ginseng (KRG) is a product from ginseng roots, which is enriched with ginsenosides and has been utilized for a long time as an adaptogen to alleviate various physiological or disease conditions. While KRG is generally considered safe, conducting a thorough toxicological assessment of the spray-dried powder G1899 during the juvenile period is essential to establish its safety profile. This study aimed to assess the safety of G1899 during the juvenile period using Sprague-Dawley rats. Methods: Two studies were conducted separately: a juvenile toxicity study and a uterotrophic bioassay. To assess the potential toxicity at systemic, postnatal developmental, and reproductive levels, G1899 was orally gavaged once a day in post-weaning juvenile Sprague-Dawley (SD) rats at 0, 1250, 2500, or 5000 mg/kg/day. Estrogenicity was assessed by orally gavaging G1899 in immature female SD rats at 0, 2500, or 5000 mg/kg/day on postnatal days (PND) 19-21, followed by a uterotrophic bioassay. These studies were conducted in accordance with the Good Laboratory Practice (GLP) regulations and regulatory test guidelines. Results: Regarding juvenile toxicity, no abnormalities related to the G1899 treatment were observed in any group during the experiment. Moreover, no uterotrophic responses were observed in the dosed female group. Based on these results, the no observed adverse effect level (NOAEL) of G1899 was determined to be at least 5000 mg/kg/day for general systemic function, developmental/reproductive function, and estrogenic activity. Conclusion: Our results suggest that G1899 is not toxic to juveniles at doses of up to 5000 mg/kg/day.

• Asian-Australasian Journal of Animal Sciences
• /
• 제26권10호
• /
• pp.1406-1415
• /
• 2013

The study was conducted to correlate the periparturient immune status in terms of neutrophil functions and cytokine expression in peripheral blood mononuclear cell culture with impending postpartum reproductive disorders in buffaloes. Forty pregnant buffaloes were observed for occurrence of postpartum reproductive disorders (PRD), i.e., metritis, endometritis and delayed uterine involution etc., during one week prepartum to four weeks postpartum period. A representative number (n = 6) of buffaloes that did not develop any PRD were included in group I (healthy, control), while the animals which experienced PRD were assigned into group II (PRD, n = 8). The blood samples were collected at weekly interval from one week prepartum to four weeks postpartum period considering the day of calving as 'd 0'. Differential leucocytes counts, superoxide and hydrogen peroxide production activity in isolated neutrophils and the mRNA expression profile of cytokines i.e., IL-2, IL-4 and IFN-${\gamma}$ in PBMC culture were studied in all the samples. A higher total leucocytes, neutrophil and band cells count along with impaired neutrophil functions i.e., lowered level of production of superoxide and hydrogen peroxide before parturition and during early postpartum period were observed in buffaloes developing PRD. Further, a lower expression of IL-2, IFN-${\gamma}$ and IL-4 mRNA in PBMC culture was observed at calving in buffaloes that subsequently developed PRD at later postpartum. Thus, suppression in neutrophil function and cytokine expression at prepartum to early postpartum period predisposes the buffaloes to develop postpartum reproductive disorders. Hence, monitoring of neutrophils function and cytokine expression profile would be effective to predict certain reproductive disorders at late pregnancy or immediately after parturition in buffaloes. In future, this may be a novel approach for determining suitable management and therapeutic decisions for prevention of commonly occurring reproductive disorders in farm animals.

• 한국응용곤충학회:학술대회논문집
• /
• 한국응용곤충학회 2001년도 추계 합동 심포지엄 및 학술발표대회
• /
• pp.65-65
• /
• 2001

• 한국동물학회:학술대회논문집
• /
• 한국동물학회 2001년도 한국생물과학협회 학술발표대회
• /
• pp.191.2-191
• /
• 2001

No Abstract, See Full Text

• 한국환경보건학회지
• /
• 제29권2호
• /
• pp.7-15
• /
• 2003

DEHP는 대표적인 플라스틱 가소제 가운데 하나로서, 광범위하게 사용되고 있으며, 내분비계 장애물질로 분류퇴고 있다. 실제로 하천, 해양, 토양 등 광범위한 환경에서 검출되고 있지만, 이 물질이 수서 생물에 미치는 내분비교란 영향과 기작에 대해서는 거의 알려진 바가 없다. 본 연구에서는 송사리로 불리우는 Oryzias latipes(Japanese medaka)와, 유생 시기에 저니성 무척추 동물로 존재하다가 성충이 되는 Chironomus riparius를 대상으로 DEHP가 내분비 장애물질로서 생식작용에 미치는 영향에 대하여 연구하였다. 먼저, Japanese medaka를 부화 직후부터 3개월간 DEHP 1, 10, 50 $\mu\textrm{g}$/l의 농도로 노출시킨 결과 암놈의 혈중 비텔로제닌의 감소 ,생식소 지수인 GSI(Gonado Somatic Index) 감소. 난자 발달 저해 등이 관찰되었다. 또한, C. riparius를 산란 직후부터 DEHP에 노출시킨 경우에는 성체 출현률, 암수 비율, 산란률에서는 용량-반응 관계를 가진 변화가 발견되지 않았으나, 산란된 알의 부화율은 DEHP에 노출된 경우 유의하게 감소하는 것이 관찰되었다. 이러한 결과를 종합하여 볼 때. DEHP는 O. latpes와 C. riparius 모두 생식 작용에 영향을 미치며, 그 작용 기작은 일반적으로 발견되는 에스트로젠(estrogen) 활성이 아닌 암놈의 생식기관의 발달을 직, 간접적으로 저해함으로서 정상적인 알의 생성을 방해하는 이른바 항-에스트로젠 기작을 보이는 것으로 추정된다. 본 연구에서는 DEHP 위해성 평가를 위한 기본 자료로서, 생식작용 영향에 대한 새로운 자료를 제시하였다.

• Reproductive and Developmental Biology
• /
• 제40권2호
• /
• pp.15-22
• /
• 2016

As a one of unsaturated fatty acid, polyunsaturated fatty acids (PUFAs) have multiple actions: as precursor of prostaglandins (PGs), steroid hormone synthesis and energy production in animal reproduction. PUFAs, which include omega-3 (n-3) and omega-6 (n-6), are derived from the diet and changed by diet, species, breed and season. The plasma membrane of spermatozoa in mammals contain various PUFAs. These composition of PUFAs regulate the membrane fluidity and cause lipid peroxidation via generation of reactive oxygen species (ROS). Induced lipid peroxidation by ROS decreased viability and motility of spermatozoa, and it is reduced by addition of antioxidant and low concentration of PUFAs. Because oocytes of animal have a high lipid components, process of oocyte maturation and embryo development are influenced by PUFAs. In in vitro study, oocyte maturation, embryo development, intracellular cAMP and MAPK activity were increased by treatment of n-3 ${\alpha}$-linolenic acid (ALA) during maturation, whereas n-6 linoleic acid (LA) negatively influenced. Also, inhibition of fatty acid metabolism in oocyte influenced blastocyst formation of cattle. PGs are synthesized from PUFAs and various PUFAs influence PGs via regulation of PG-endoperoxide synthase (PTGS). Steroid hormone synthesis from cholesterol is regulated by expression of steroid acute regulator (StAR) protein and mRNA. Exogenous n-3 and n-6 PUFAs altered sex hormone in animal through stimulate or inhibit StAR activity. Because PUFAs altered PG and steroid hormone synthesis, follicular development was influenced by PUFAs. This effect of unsaturated fatty acid could provide information for improvement of reproductive ability in animals.

• Journal of Forest and Environmental Science
• /
• 제34권6호
• /
• pp.435-450
• /
• 2018

Phenological events of four Rhododendron tree species (viz. R. arboreum, R. arboreum ssp. delavayi var. delavayi, R. barbatum and R. kesangiae) was monitored in temperate mixed broad-leaved forests of Arunachal Pradesh, India. Phenological events like flower bud formation, flowering, fruit setting, fruit maturing, seed dispersal, leaf bud formation, leaf flushing, and leaf shedding were recorded. Indices i.e., phenophase sequence index (PSI), active phenophasic period of the species (APS) and index of reproductive/vegetative activity (RVA) were also calculated. Present study revealed that bark consistency, growth form and leaf pattern of the studied species have showed variations among the species. Rhododendron species exhibited the phenological events overlapping with other phenophases. The peak flower bud formation was observed during the winter; R. arboreum ssp. delavayi var. delavayi start flowering from December, while the flowering in rest three species exhibited during February to April. Fruit setting occurred during summer to autumn while fruit maturation revealed peak during November. Leaf bud formation illustrated two peaks in April and May, leaf flushing exhibited peak in June, while leaf shedding peaked during October to November. Active phenophasic period of the species were found 12 months, which revealed that species engage in various phenophase activities throughout the year. Phenophase sequence index ranged between 0.8 to 0.9 (PSI ${\geq}0.6$), signifies that species have a sequential arrangement of phenophases. Index of reproductive/vegetative activity of the species exemplified >1, indicate that the reproductive phenophases were dominance over vegetative phenophases. The study have provided substantial insight on the life cycle events of Rhododendron species and ecological approaches for further scientific study with recent climate change and effective management and conservation.

• 보건교육건강증진학회지
• /
• 제17권1호
• /
• pp.19-39
• /
• 2000

The purpose of this study was to examine the prevalence and correlated factors of sexual behavior among high school students in Seoul A sample of 233 male and 248 female high school students were analyzed using cross-tabulation and logit regression models. Correlated factors examined include type of school, level of mothers education, perceived living status of family, whether family has two parents or not, and whether students have ever lived away from the family, whether students received reproductive health education at school and whether they have friends with sexual experience, whether students have ever smoking and alcohol drinking. The prevalence of alcohol drinking was 73% among boys and 55% among girls and the prevalence of smoking was 64% of boys and 40% of girls, whereas the prevalence of sexual activity was 27% among boys and 15% among girls. Risk taking was more prevalent among boys than among girls. Multiple risk taking behavior was common for both boys and girls. Students who did not have two parents were more likely to engage in risk taking behavior than those who had two parents. For both boys and girls, the factor that affects their own sexual activity most was having a friend who was sexually active and having an experience of living away from their family also increases the odds. For girls, the factor that affects having experience of alcohol drinking and smoking. Receiving reproductive health education at school had no effect on students sexual behavior. Much higher risk taking behavior with sexual behavior among students in Seoul implies that the overall prevalence of risk taking behavior among high school students was likely to rise as South Korea continues its modernization. In-school and community health education programs need to be modified to be effective in protecting students from risk taking sexual behavior.

• 한국발생생물학회지:발생과생식
• /
• 제24권4호
• /
• pp.263-275
• /
• 2020

The proper administration of melatonin has well been documented to induce testicular regression in seasonal breeding animals. The subcutaneous injections of melatonin in the afternoon, not in the morning, consistently occurred testicular involution in the male Syrian (golden) hamsters whose reproductive activity is regulated by the photoperiod. But the effects of daily melatonin via gavage have not been estimated. Golden hamsters housed in long photoperiod (LP) were divided into 5 groups: the control animals housed in LP or in short photoperiod (SP) and animals treated daily with low (15 ㎍), middle (150 ㎍), and high dosages (1,500 ㎍) of pure melatonin by using gavage in the evening for 8 weeks. As results, LP control animals had large testes and SP controls displayed small and entirely regressed testes. The animals treated with various dosages of melatonin showed collectively degenerating effects on the weights of testes, epididymides, and seminal vesicles in the middle and high dosage groups, with the individual differences as well. The high dosages induced testicular regression in more proportion than the middle dosages did. The low dosage had large testes like the LP control animals. The small and inactive testes shown in some animals of both middle and high groups presented the complete regression as those of the animals maintained in SP. These results strongly suggest that the administrations of melatonin lead to testicular involution in the male golden hamsters when it is administered through gavage.