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        검색결과 141

        1.
        2024.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 일본의 저출산 문제에 대한 정책적 대응이 어떤 경로로 형성 되고 변화되었는가의 과정을 역사적 제도주의 관점에서 분석한 것이다. 이를 위하여 저출산 정책이 형성된 1990년대 초 엔젤플랜에서 2003년 소자화사회대책기본법의 입법화가 이루어지는 시기에 집중하여 살펴보았 다. 이를 통한 결과는 첫째, 정책형성의 경로는, 1990년 저출산율의 1.57 쇼크라는 외부적 충격에 의한 중대국면에서 과거 일본 정부의 산아 조절 정책의 연속선이라는 우려에서 분리되고자 하는 역사적 유산과의 단절의 측면에서 경로의존적 특성을 보이는 것으로 해석되었다. 둘째, 정 책변화의 경로는, 제도 내부적인 새로운 정책이념의 등장, 저출산 문제의 심각성에 대한 거부권 없는 정치적 합의와 정책 결정 구조의 체계화, 새 로운 제도 내용의 추가적 누적이라는 제도적 맥락을 통해 경로진화와 제 도의 가겹의 특성을 보이는 것으로 해석되었다. 이러한 경로 과정을 고 찰하면서 일본 저출산 정책의 특성과 한계를 살펴보았다.
        6,600원
        2.
        2024.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        출산에 관한 의사결정은 미시・거시차원의 여러 요인들이 복합적으로 작 용하여 단순하지 않다. 낮은 합계출산율 제고를 위한 다양한 노력이 오랫동 안 경주되고 있으나 젊은층의 출산패러다임의 변화에 기반을 둔 가치관, 성 평등변수를 반영한 합계출산율 영향요인을 분석한 국내연구가 필요하다. 본 연구는 합계출산율에 영향을 미치는 요인을 가치관, 경제적, 성평등 요인으 로 구분하여 통계분석을 실시하였다. 설명변수에서 자녀가치관, 남성의 육아 참여도, 성별가사분담률 등의 개선과 추가는 선행연구와 차별되는 점이다. 16개 광역시도의 2005-2022년 데이터를 패널화하여 Pool OLS, 고정효과 및 확률효과모형으로 회귀분석을 실시하였는데 분석결과는 다음과 같다. 첫 째, 자녀가치관은 서구적인 가치관이 아닌 결혼에 기반을 둔 자녀출산이라는 관점이 1% 유의수준에서 합계출산율에 정적 영향을 미쳤다. 둘째, 선행연구 와 달리 사교육비의 영향이 출산율에 즉각적으로 반영되지 않았으며, 0.1% 유의수준에서 아파트매매가격지수가 높을수록 합계출산율에 정적 영향을 미 쳤다. 셋째, 소득이 보장되지 않는 남성육아휴직은 합계출산율 감소와 연결 되며, 여성고용률과 합계출산율의 관계는 유의미하지 않아 선진국 모형과 다 르다는 것을 확인하였다.
        6,300원
        3.
        2024.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        As China’s issues of sub-replacement fertility and an aging population intensify, the impact of population factors on the economic growth of countries and regions has become significant. This study uses change point analysis to divide the time panel data from 2002 to 2022, with 2010 as the dividing point, to separately examine the impact of dependency ratios and education on economic growth before and after 2010. The study found that before 2010, the family planning policy and the baby boom resulted in a negative impact of the child dependency ratio on economic growth, while the low birth rate and the gradual aging of the baby boom population led to a negative impact of the elderly dependency ratio on economic growth. After 2010, with the further development of the silver economy and the gradual delay of retirement age, the elderly dependency ratio began to positive impact on economic growth, but the child dependency ratio did not significantly promote economic growth. Additionally, education has consistently had a significant positive effect on economic growth. In response, the Chinese government can address the issue of low birth rate by increasing financial subsidies and tax reductions to raise the birth rate. To tackle the problem of an aging population, the government can increase labor force participation and develop the silver economy. At the same time, the significant developing high-quality education and promoting technological advancement for economic development are crucial for economic growth.
        5,500원
        4.
        2024.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Korea is facing a significant problem with historically low fertility rates, which is becoming a major social issue affecting the economy, labor force, and national security. This study analyzes the factors contributing to the regional gap in fertility rates and derives policy implications. The government and local authorities are implementing a range of policies to address the issue of low fertility. To establish an effective strategy, it is essential to identify the primary factors that contribute to regional disparities. This study identifies these factors and explores policy implications through machine learning and explainable artificial intelligence. The study also examines the influence of media and public opinion on childbirth in Korea by incorporating news and online community sentiment, as well as sentiment fear indices, as independent variables. To establish the relationship between regional fertility rates and factors, the study employs four machine learning models: multiple linear regression, XGBoost, Random Forest, and Support Vector Regression. Support Vector Regression, XGBoost, and Random Forest significantly outperform linear regression, highlighting the importance of machine learning models in explaining non-linear relationships with numerous variables. A factor analysis using SHAP is then conducted. The unemployment rate, Regional Gross Domestic Product per Capita, Women's Participation in Economic Activities, Number of Crimes Committed, Average Age of First Marriage, and Private Education Expenses significantly impact regional fertility rates. However, the degree of impact of the factors affecting fertility may vary by region, suggesting the need for policies tailored to the characteristics of each region, not just an overall ranking of factors.
        4,000원
        5.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Toll-like receptor 4 (TLR4) is known to contribute to the modulation of insulin resistance and systemic inflammation seen in obesity and the metabolic syndrome. The present study was performed to investigate the fertility competence of TLR4 knock out male mice (TLR4 mice) on a high-fat diet (HFD), compared to a normal-chow diet (NCD). The controls included wildtype (WT) mice fed on a HFD or NCD. Six-week-old male mice were fed with either a NCD or HFD for 20 weeks. Body and organ weights, serum levels of glucose, triglycerides and hepatoxicity, sperm quality and spermatogenesis were observed after the sacrifice. Also, randomly selected male mice were mated with virgin female mice after feeding of 19 weeks. The weight of the body and organs increased in WT and TLR4 mice on a HFD compared to those of mice on a NCD. The weights of the reproductive organs did not vary among the treatment groups. The motility and concentration of the epididymal spermatozoa decreased in both WT and TLR4 mice fed a HFD. The pregnancy rate and litter size declined in the HFD-fed WT mice compared to the HFD-fed TLR4 mice. In conclusion, the HFD alters energy and steroid metabolism in mice, which may lead to male reproductive disorders. However, fertility competence was somewhat restored in HFD-fed TLR4 male mice, suggesting that the TLR4 is involved in testis dysfunction due to metabolic imbalance.
        4,300원
        6.
        2023.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 한국의 고질적인 사회문제로 되는 저출산 현상의 대안을 제 시하는데, 그 목적이 있다. 미래 적 소유잠재성의 시각에서 출산으로 인 해 국가, 개인, 기업이 얻을 수 있는 것과 상실하게 되는 것들을 파악하 고, 이를 보완할 수 있는 대안을 제시한다. 국가에게 저출산의 지속은 생 존을 위협하며, 자기보존을 어렵게 한다. 출산은 국가의 생존과 관련한 문제로 볼 수 있다. 반면에 오늘날 개인에게 출산과 양육은 자산의 감소 는 물론 현재의 일자리를 위협한다. 저출산의 해결방안은 미래 세대 츨 생을 개인의 상속재산 지분과 연계하며, 국가지원금과 합의된 평균자녀 수와 평균자녀수 분포와 연계하는 것이다. 본 연구에서는 차세대 국가를 이끌어갈 미래 세대 존재를 개인 상속재산과 국가의 예산 및 지원금과 연계하여 저출산의 대안을 제시하였다.
        6,000원
        7.
        2023.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 저출산 현상이 가속화 되고 있는 상황에서 임신・출산・육아 의료 서비스의 현황과 지역적 불균형을 탐색하되 행정구역 내 변이를 고려하여 분석하는 것을 목적으로 한다. 이를 위해 공간분석 단위를 세분화하여 행정구역 내에서도 의료기관의 접근성에 격차가 있는지를 확인하였다. 가임연령 여성 및 0~5세 인구를 수요로 간주하고, 임신・출산・육아를 진료 과목으로 하는 전문의 및 응급병상의 규모와 분포를 수요와의 공간적 배치를 고려한 공간적 접근성을 산출하였다. 분석 결과 수요에 비해 임신・출산 인프라의 지역간 공급이 불균등하게 분포하고 있음을 확인할 수 있었고 접근성이 취약한 지역은 특정 지역으로 수렴되는 것을 확인할 수 있었다.
        4,500원
        8.
        2022.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The impact of heat stress (HS) on reproductive performance and its problems in cows remains to be investigated in Bangladesh. The study was, therefore, aimed to evaluate the effect of HS on fertility and reproductive health problems of dairy cows in a selected area of Bangladesh. A total of 1,095 cows from 500 farms were included in this study. The climate-related data were recorded daily basis for every month in a year and temperature-humidity index (THI) values were calculated to determine the level of HS. Concurrently, data on fertility parameters [number of services per conception (NSC), conception rate (CR) and calving to the first service interval (CFSI)], and reproductive problems were collected through a pre-defined questionnaire. The results show that crossbred [Native x Holstein-Friesian, (HF)] cows were more vulnerable (p < 0.05) to a magnitude of HS effects considering physiological parameters of cows [age, body condition score (BCS), parity and milk yield]. Regarding fertility, HS had no effect on NSC, CR and CFSI in both native and crossbred cows (p > 0.05). The findings on the reproductive problems indicate that HS had significant influence on the prevalence of anestrus (χ2 = 21.814, p < 0.05) and retained placenta (χ2 = 24.632, p < 0.05) in cows. Of note, the prevalence of repeat breeding syndrome was 2.5 folds higher in stress condition than in no stress condition. Abortion and dystocia were not influenced by HS. In conclusion, HS does not influence the fertility parameters of cows studied; however, anestrus and retained placenta are likely to occur under HS conditions in cows.
        4,000원
        9.
        2022.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Cryopreservation of porcine ovarian tissue by vitrification method is a promising approach to preserve genetic materials for future use. However, information is not enough and technology still remains in a challenge stage in pig. Therefore, the objective of present study was to determine possibility of vitrification method to cryopreserve porcine ovarian tissue and to confirm an occurrence of cryoinjuries. Briefly, cryoinjuries and apoptosis patterns in vitrified-warmed ovarian tissue were examined by histological evaluation and TUNEL assay respectively. In results, a damaged morphology of oocytes was detected among groups and the rate was significantly (p < 0.05) lower in vitrification group (25.8%) than freezing control group (67.7%), while fresh control group (6.6%) showed significantly (p < 0.05) lower than both groups. In addition, cryoinjury that form a wave pattern of tissues around follicles was found in the frozen control group, but not in the fresh control group as well as in the vitrification group. Apoptotic cells in follicle was observed only in freezing control group while no apoptotic cell was found in both fresh control and vitrification. Similarly, apoptotic patterns of tissues not in follicle were comparable between fresh control and vitrification groups while freezing control group showed increased tendency. Conclusively, it was confirmed that vitrification method has a prevention effect against cryoinjury and this method could be an alternative approach for cryopreservation of genetic material in pigs. Further study is needed to examine the viability of oocytes derived from vitrified-warmed ovarian tissue.
        4,000원
        10.
        2022.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 우리나라 Holstein의 번식형질에 대한 유전모수를 추정하기 위하여, 2009년부터 2013년까지 분만한 농협 젖소개량사업소의 검정자료 경산우 144,793두의 211,899개의 번식기록을 이용하였다. 7가지 형질의 유전 및 오차 (공)분산을 WOMBAT 패키지를 이용하여 분석하였다. CTFS, GL, NRR, NS, FSTC, DO 및 CI의 유전력은 각각 0.064, 0.060, 0.005, 0.014, 0.012, 0.021 및 0.021로 추정되었다. 형질들 간의 유전상관은 –0.910에서 0.995로 나타났다. NRR과 NS, NRR과 FSTC 간에는 부의 유전상관이 나타났으나, DC와 CI는 강한 양의 유전상관을 나타냈다. CTFS와 FSTC는 DO 및 CI와 유의하게 양의 유전상관관계를 나타냈다(0.479~0.862). CTFS와 FSTC 사이의 낮은 유전상관은 두 형질이 서로 다른 유전적 측면에 있다는 것을 의미한다. 본 연구는 번식능력 개량을 위한 기초 자료를 제공할 수 있을 것이라 판단한다.
        4,000원
        11.
        2021.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Rye (Secale cereal L.) is the most tolerant to abiotic stress including low temperature, drought, and unfavorable soil conditions among the winter cereals. Rye is the rapid growth of early spring results from increasing areas for the use of the forage and green manure in the middle part of Korea. “Jungmo2509”, a rye cultivar was developed by the National Institute of Crop Science (NICS), RDA in 2014. It was developed from a cross between “Olhomil”, a self-compatible cultivar, and “Synthetic Ⅱ”, a self-incompatible line. “Jungmo2509” is an erect plant type and of a middle size, with a green leaf color, a yellowish-white colored culm, and a yellowish brown-colored, small-size grain. The heading date of “Jungmo2509” was April 23, which was 5 days later than that of “Gogu”, respectively. But “Jungmo2509“ showed greater resistance to lodging compared to that of the check cultivar, with similar to winter hardiness, wet injury, and disease resistance. “Jungmo2509” was a higher to than “Gogu” in terms of protein content (9.4% and 8.0%, respectively), total digestible nutrients (TDN) (55.7% and 55%, respectively). The seed productivity of “Jungmo2509” was approximately 2.08 ton 10a-1, which was 11% lower than that of the check. Almost all rye cultivars are out-crossing due to genes controlling incompatibility, but “Jungmo2509” is higher seed fertility (56%) than that of Gogu (0%). it has self-compatible genes. “Jungmo2509” is erect in plant type and resistance for lodging. Therefore, “Jungmo2509” can produce uniform seeds for processed grains of human consumption and utilize them as parents for breeding the rye hybrids with high forage yields.
        4,000원
        12.
        2020.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The effects of the number of frozen-thawed ram sperm per single and double intra-cervical artificial insemination (AI) on fertility in ewes were studied. A total of 89 non-pregnant ewes were synchronized for oestrus with two doses of 100 μg PGF2α (Cloprostenol) 9 days apart. The ewes were randomly assigned to one of four groups; D200 (n = 23; double AI with 200 × 106 sperm), S200 (n = 24; single AI with 200 × 106 sperm), D100 (n = 24; double AI with 100 × 106 sperm) and S100 (n = 18; single AI with 100 × 106 sperm). Ewes were inseminated within 12 to 18 h for single AI and, within 10 to 12 h and 16 to 18 h for double AI after the onset of oestrus. The onset of oestrus ranged from 28 to 76 h (54.33 ± 1.28 h). The high percentage (29.2%) of ewes showed oestrus between 51 to 60 h. The non-return rates were highest in group D200 (56.5%) and differed significantly (p < 0.05) from group S100 (11.1%). No ewes were pregnant in group S100, and the pregnancy rates among the remaining groups did not differ. The mean gestation period was 152.8 ± 0.5 days and no difference was observed among the groups. The lambing and multiple birth rates were 100% in group D200. The single and twin lambing was highest in group D100 (33.3%) and group D200 (83.3%), respectively. Only one triplet lambing and the highest lambing size (2.2 ± 0.2) was recorded in group D200. In conclusion, double AI with 200 × 106 sperm showed comparatively most practical for achieving high pregnancy rates and lambing performances in Bangladeshi ewes under field conditions.
        4,000원
        13.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        감자수염진딧물 (Macrosiphum euphorbiae)의 온도별 발육은 12.5~27.5°C까지 2.5°C 간격 (상대습도 65±5%, 광주기 16L : 8D), 7개 온도조건에서 1~2령, 3~4령의 2단계로 구분하여 조사하였다. 약충의 사망률은 7개 온도 중 6개 온도에서 10% 미만이었으나, 27.5°C에서 사망률은 53.0% 였다. 온도별 발육기간은 15.0°C에서 15.5일, 25.0°C에서는 6.7일로 고온으로 갈수록 발육기간은 짧아졌으나, 27.5°C 에서는 발육기간이 다시 길어져 9.7일이었다. 약충의 발육 영점온도는 2.6°C였고, 유효적산온도는 144.5일도였다. 약충의 발육을 5가지 비선형발육모형에 적용한 결과 Logan6 (r2=0.99) 모형이 발육에 적합하였고, 발육완료분포모형은 2-Weibull과 3-Weibull의 모형 적합성 (r2)이 각각 0.92 와 0.93으로 유사하였다. 성충 수명과 산자 수에서 성충 수명은 온도가 증가함에 따라 짧아지는 경향을 보였고, 산자 수는 20.0°C에서 64.4개로 가장 많은 산자를 생산하였다. 생명표분석에서 순증가율 (R0)은 20.0°C에서 63.2로 가장 컸고, 내적자연증가율 (rm)은 25.0°C에서 1.393로 가장 컸다. 배수증가기간 (Dt)은 25.0°C에서 2.091로 가장 짧았다. 기간자연증가율 (λ)은 25°C에서 가장 컸고 (1.393), 평균세 대기간 (T)은 25°C에서 9.929로 가장 짧았다.
        4,200원
        14.
        2019.04 구독 인증기관·개인회원 무료
        Females of adzuki bean beetle (ABB), Callosobruchus chinensis (L.), a cosmopolitan field-to-storage pest of legumes, release sex pheromone consisting of two isomeric components, 2Z-homofarnesal and 2E-homofarnesal. Two day old virgin ABB adults were exposed to sub-lethal fumigation doses (LC25=0.0056 and LC50=0.0076 mgL-1) of phosphine (PH3) to evaluate the effects on adult longevity, fertility and sex pheromone production. Longevity (female; P < 0.001, male; P < 0.001), fecundity (P < 0.001) and sterility (P < 0.001) were significantly affected. The GC-MS for solid phase micro extraction exhibited the significant reduction of release of both of the pheromone components; 2Z-homofarnesal (P < 0.0038) and 2E-homofarnesal (P = 0.0009) when the females were exposed to LC25 dose of PH3. This study unveils the detrimental effects of PH3 fumigation on some of the biological parameters of ABB.
        15.
        2018.11 구독 인증기관·개인회원 무료
        Bisphenol A (BPA) is a common industrial chemical that has been used extensively to make certain plastics and resins since the 1960s. As a potential endocrine disruptors, BPA has been investigated for its impact on fertility/reproduction in animals and humans. However, the molecular mechanisms of BPA action and standard method for detecting BPA-related health hazards are unclear. Considering in-vitro experimental model, we investigated the effects of BPA (0.0001 to 100 μM) exposure on mouse spermatozoa. We revealed that BPA affects several sperm functions by triggering the mitogen-activated protein kinase, phosphatidylinositol 3-kinase, and protein kinase-A (PKA) activity. High doses of this chemical was also likely for the activation of protein tyrosine phosphorylation in a PKA-dependent signaling consequently induced a precocious acrosome reaction. Simultaneously, BPA has been found to decrease the rate of fertilization and early embryonic development. In addition, BPA induced differential protein expression in spermatozoa were responsible for the pathogenesis of many diseases. Considering in vivo experimental model, we deliberate the effects of gestational BPA exposure (TDI, NOAEL, and LOAEL doses) on both ejaculated and capacitated spermatozoa in F1 adult mice. We confirmed that BPA affects several sperm function in F1 male. These effects appeared to be caused by reduced numbers of stage VIII seminiferous epithelial cells in testis and decreased PKA activity and tyrosine phosphorylation (non-capacitated) in spermatozoa. We also noticed that BPA decreased average litter size as well as compromise the rates of cleavage and blastocyst formation. Proteins differentially expressed in both capacitated/ejaculated spermatozoa play a critical role in energy metabolism, stress responses, and fertility, finally predispose to the development of several diseases. On the basis of these results, we suggest that BPA alter spermatozoa function and the proteomic profile, ultimately affecting their fertility potential. Therefore, it is of critical public health significance to reevaluate the levels of BPA exposure that are currently deemed to be acceptable.
        16.
        2017.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to investigate the optimal artificial insemination (AI) time with diagnostic kit at ovulation time. We already applied the patent about the protein in the cow heat mucose in external reproductive tract. And we would examine the accuracy for detection of cow heat by the kit produced with the protein. Evaluation of optimal heat detection was tried two time at 12 hrs and 24 hrs after the heat. And then, AI service also performed two times with no relation to the results of heat diagnosis by heat detection kit and pregnancy rates were checked with rectal palpation on 60th day after AI. Heat diagnostic results by kit in natural heat after 12 hrs in Hanwoo cows were showed 31.3~75.0% on positive in first heat detection and 33.3~100.0% on positve in second heat detection. In the 1st positive results were significant different (p<0.05), but 2nd positive were not. The results of heat detection showed different result on regional influence and individual cow effects. The pregnancy rates of first trial of heat detection were showed 34.4~78.7% on positive and 21.3~68.8% on negative after the diagnosis by heat detection kit. And the pregnancy rates of next trial of heat detection were showed 33.3~85.7% on positive and 14.3~66.6% on negative after the heat diagnosis. Both positive results of first trial and next trial also were showed significant different (p<0.05), but negative results were not. In positive result, first trial of total pregnancy rates was higher than the next trial of pregnancy, but there showed opposite results on negative results. In conclusion, the optimal heat detection kit is suitable to ordinary Hanwoo cows and it suggested that we have to improve the kit’s accuracy by detecting the materials like proteins related optimal AI time.
        4,000원
        17.
        2017.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Euiam and Paldang Reservoirs have often been facing water quality problems, such as eutrophication, algal blooms and off-flavors by treated wastewater effluent (TWE) in the North-Han and the Han River basins, but little is examined on the direct biological effect of TWE. This study tested algal growth potential (AGP) of four TWEs discharged into Euiam and Paldang Reservoirs to evaluate water fertility in September 2014 and March and September 2015. Test alga was used Anabaena circinalis isolated from Paldang Reservoir. Mean concentration of T-N and T-P in TWEs was 3,956.7 μg N L-1 and 50.8 μg P L-1, and the proportion of NO3-N and PO4-P to the total fraction was 72.1% and 40.8%, respectively. Both N and P were high in TWEs, but much higher N than P concentration indicates strong P-limitation. As a consequence, the maximum AGP was determined by PO4-P concentration (r=0.998, p<0.01). Mean AGP value was 15.4 mg dw L-1 among four effluents indicating its eutrophic condition. Due to the establishment of tertiary (advanced T-P) treatment method in the studied plants recently, P concentration was significantly decreased in TWEs compared to the years prior to 2012. However, P concentration seems to be still high enough to cause eutrophication and algal blooms. Therefore, wastewater treatment to P-free level needs to be considered if effluents are directly discharged into the drinking water resources.
        5,100원
        18.
        2016.10 구독 인증기관·개인회원 무료
        Bisphenol‒A (BPA) is a known endocrine‒disrupting chemical used extensively to manufacture plastic bottles, canned food linings, thermal receipts, and other commonly used items. BPA is capable of inducing chromosomal alterations in germ cell line, thereby produced transgenerational effects on brain function, social recognition, reproductive diseases, sperm quality, gene expression, and obesity. Here, we aimed to investigate the transgenerational effects of BPA on murine male fertility. Six-week-old male mice (F0) were gavaged with corn oil (control), two different doses of BPA (5 mg, and 50 mg·kg bw-1·day-1),andethinylestradiol(EE,0.4mg·kg bw-1·day-1), dailyfor6weeks. Treated male mice were mated with wild‒type female and sibling pairs were bred up to the third generation (F3) in a similar manner with no further BPA exposure. Testes and spermatozoa were collected from 14-week-old males of all generation (F0 to F3) to evaluate testis weight, sperm function, and fertility. We found that high concentration of BPA significantly increased testicular weight in F2. Although the sperm viability, capacitation status, and intracellular ROS levels were not affected by BPA, however, sperm count, motility, hyperactivated motility, and intracellular ATP levels were significantly altered by BPA, dose dependently. In majority of the cases the effects were prominent in F2 followed by F1 and F0, whereas the effects were diminished in F3 generation. Simultaneously, high concentration of BPA significantly decreased cleavage and blastocyst formation rate in both F1 and F2. Similar inhibitory effects on cleavage and blastocyst were also noted in F1 by low dose of BPA. Depending on these findings we conclude that BPA decreases the fertility potential of exposed males and has an adverse impact on sperm function and fertility in subsequent generations.
        19.
        2016.10 구독 인증기관·개인회원 무료
        Sperm adhesion molecule 1 (SPAM1) and Hyaluronidase 5 (HYAL5) has been well-known as assistants for sperm penetrate through the cumulus mass surrounding the ovulated eggs. However, so far their role in mammalian fertilization remain elusive, because mouse sperm lacking SPAM1 or HYAL5 were still capable of penetrating the cumulus mass despite a delayed dispersal of cumulus mass. Those data collectively demonstrated that SPAM1 or HYAL5 deficiency alone was not sufficient to cause male infertility in mice. In the present study, SPAM1 and HYAL5-simultaneous deficient male mice model was generated. Because of inhibition in sperm hyaluronidases, SPAM1 and HYAL5-deficient male mice produced significantly smaller numbers of offspring than hetero type and wild type mice. Hyaluronic acid degradation assay and cumulus oocyte complex dispersal assay as well as sperm motility assay using double knock out sperm and extracts had severe adverse effects on the dispersal of cumulus oocyte complex, which was the main reason for the impaired fertility of double knock out male sperm. Moreover, hyaluronic acid degradation assay using human sperm extracts revealed that sperm hyaluronidase has a principal role in sperm penetration through the cumulus oocyte complex. In conclusion, our results suggest that sperm hyaluronidase deficiency may be sufficient to cause male sterility in mammal because SPAM1 and HYAL5 deficiency sperm not impaired the sperm motility in hyaluronic acid but also cumulus oocyte complex penetration.
        20.
        2016.10 구독 인증기관·개인회원 무료
        Jeju Black Cattle (JBC) is an indigenous species of Korea and their mass production and industrialization are required for this high quality indigenous species. For production of elite JBC zygotes, selection of high quality sperm is necessary for in vitro fertilizatioin. In this study, we compared the sperm fertility and developmental capacity of IVF embryos using various JBC sperm (Bull A, B and C). The frozen semen was thawed and confirmed sperm viability and motility. In addition, frozen-thawed sperm was used for a chlorotetracycline(CTC) staining assay and in vitro fertilization. Sperm were classified into three staining patterns. The F pattern is indicative of uncapacitated sperm, the B pattern is indicative of capacitating and capacitated sperm and the AR pattern is indicative of acrosome-reacting sperm or acrosome-reacted sperm, respectively. Several kinds of JBC sperm was inseminated in 44 ㎕ IVF drop contained 10 oocytes with sperm concentration of 1 × 106 cells/ml, and then 2 ㎕ heparin and 2 ㎕ PHE (20 μM penicillamine, 10 μM hypotaurine, 2 μM epinephrine) were added. The sperm viability and motility were higher in sperm 3 species (n=8). When we confirmed sperm capacitation, F pattern and B pattern rate were higher than AR pattern in sperm A group. After IVF, the rates of cleavage and blastocyst development were higher in sperm C group compared to other sperm group. However, the cell number of blastocyst was higher in sperm E group. These results demonstrate that the use of sperm C was effective in production of elite JBC IVF embryos. Additional experimental data are required for more accurate analysis.
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