• Clinical and Experimental Reproductive Medicine
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• 제19권2호
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• pp.143-152
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• 1992

The present experiments were focussed to modify a short slow-cooling protocol used for freezing of early stage embryo(Testart et al., 1986) and also to apply the modified method for the cryopreservation of hamster oocytes with Zona or without. The protocol was modified by changing the 4-step equilibration into 1-step and the 1-step thawing into 2-step. The oocytes were added in 1.5M PROH and 0.1M Sucrose, seeded at $-7^{\circ}C$, slow cooled($0.3^{\circ}C$/min) to $-30^{\circ}C$ before plunging to $-196^{\circ}C$. The oocytes were thawed at $23-25^{\circ}C$ air(20sec/150sec) and/or 33-35 water(10sec). The survival of the frozen-thawed oocytes was determined by morphologic criteria and their fertilizing ability was also estimated by Sperm Penetration Assay(SPA) system(Chang et al, 1990) using fertile men semen sample. One-step equilibration showed slightly higher survival rate(83.9% vs. 71.0%) and fertilization rate(83.9% vs. 71.0%) compared with four-step(p>0.05). And two-step thawing(air & water exposing) of oocytes frozen after 1-step equilibration showed significantly higher survival rate(96.3%) than one-step thawing at air(85.2%) or water(65.0%) only(p<0.05). Therefore, by the modified method(l-step equilibration & 2-step thawing), Zona-intact(ZI) and Zona-free(ZF) oocytes were frozen and thawed. ZI-oocytes showed significantly higher survival rate(95.4%, 308/323 vs. 67.6%, 240/355) than ZF-oocytes(P<0.01). But the survival of ZF-oocytes was as high as ZI-oocytes in fourteen of twenty-four replicates. ZI-oocytes was also significantly higher fertilization rate($92.4{\pm}8.9%$ vs. $63.7{\pm}18.5%$) and higher mean number of penetrated sperm($6.2{\pm}4.2$ vs. $3.9{\\pm}3.3$) than ZF-oocytes, but not higher than control(fresh oocytes;$99.3{\pm}2.4%$, $8.4{\pm}4.2$)(P<0.001). Conclusively, this modified method will contribute to freeze effectively the hamster oocytes for simplifing of the logical consideration of performing SPA and also to freeze the human and other animal oocytes.

• Asian-Australasian Journal of Animal Sciences
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• 제16권1호
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• pp.23-28
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• 2003

The present study was undertaken to investigate the effects of PVP concentration and exposure temperature to vitrification solution on the post-thaw survival, in vitro maturation and development of immature bovine oocytes (germinal vesicle stage). The vitrification solution (VS) consisted of 40% ethylene glycol (EG)+0.5 M sucrose (S)+10% FBS. PVP was added to VS: 0%, 5% or 10%. The cumulus-oocyte complexes (COCs) were diluted in VS as one step, after 2 min the COCs were loaded in straw and vitrified by direct immersion into liquid nitrogen. For thawing, the straws were plunged into $30^{\circ}C$ water bath for 10s. After thawing, the oocytes were diluted in 0.5 M (in DPBS with 10% FBS) sucrose solution for 5 min. The survival rate (FDA-test and trypan blue) of immature bovine oocytes was measured. The survival rate was higher in 5% PVP (91.5%) than in 0% (64.2%) or in 10% PVP (79.7%). The proportion of metaphase II formation was 69.35% in control (no vitrified COCs), 9.3% in 40% EG+0.5 M S+0% PVP and 21.05% in 40% EG+0.5 M S+5% PVP (p<0.05). The effect of room temperature ($25^{\circ}C$ for 10 min) and cold temperature ($4^{\circ}C$ for 10 min) on COCs were determined in this study. After IVF, the cleavage and blastocysts rate of oocytes exposed to room temperature and cold temperature in VS+5% PVP was significantly different (2 cell: 63.20% vs 37.97%, blastocysts: 18.40% vs 2.53%). The cleavage rates of frozen-thawed oocytes were 20.53% with PVP and 22.13% without PVP (p>0.05). Two out of 151 oocytes (1.32%) developed to blastocyst stage after frozen-thawed with 5% PVP (p>0.05). Development of oocytes after frozen-thawing to the 2 cell were not significantly affected with or without PVP following IVF. However, the vitrification of immature bovine oocytes with PVP maintained the ability to develop to the blastocyst stage after IVM-IVF and IVC, while no blastocysts were obtained from oocytes vitrified without PVP. These results suggested that PVP has a protective role for vitrification of immature bovine oocytes as far as survival is concerned, however, the protection was not sufficient enough to support blastocyst formation.

• 한국산림과학회지
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• 제40권1호
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• pp.43-50
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• 1978

본(本) 연구(硏究)는 천연식용색소(天然食用色素)와 고급주(高級酒)및 천연과실(天然果實) 음료(飮料) 개발(開發)의 중요자원(重要資源)이 되는 Elder berry의 다량증식(多量增殖)과 보급(普及)을 위(爲)하여 각처리별(各處理別)로 삽목실험(揷木實驗)을 실시(實施)한 결과(結果)다음과 같은 결과(結果)를 얻었다. 1. 삽목상(揷木床)은 온실내(溫實內)에 온도(溫度)와 습도(濕度)를 완전자동화(完全自動化) 할때에 100%의 활착(活着)을 높일 수 있었고 처리간(處理間)에는 1%의 높은 유의성(有意性)이 있었다. 2. 품종간(品種間) 비교실험(比較實驗)에 있어서는 평균(平均) 93.8%의 삽목활착율(揷木活着率)을 보였고 품종내(品種內)에는 유의성(有意性)이 없었다. 3. 삽수(揷穗)의 각기관별(各器管別) 실험(實驗)에서는 평균(平均)57.5%의 삽목활착율(揷木活着率)을 냈으며 휴안지(休眼枝) 2 마디를 쓰는 것이 가장 좋았으며 처리간(處理間)에는 1%의 유의성(有意性)을 보였다. 4. 휴안아(休眼芽)의 삽목(揷木)이 가능(可能)하여 17.66%의 활착(活着)이 되었다. 5. 조직(組織)의 분화별(分化別) 및 경화도(硬化度)에 따른 삽목활착(揷木活着)에는 1% 이상의 유의성(有意性)이 있었고 6月 15일경(日頃)의 반숙지(半熟枝)인 경우가 54%로서 가깅 좋은 결과(結果)를 얻었다.

• Journal of Veterinary Science
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• 제23권1호
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• pp.8.1-8.15
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• 2022

Background: Brucella infection induces brucellosis, a zoonotic disease. The intracellular circulation process and virulence of Brucella mainly depend on its type IV secretion system (T4SS) expressing secretory effectors. Secreted protein BspJ is a nucleomodulin of Brucella that invades the host cell nucleus. BspJ mediates host energy synthesis and apoptosis through interaction with proteins. However, the mechanism of BspJ as it affects the intracellular survival of Brucella remains to be clarified. Objectives: To verify the functions of nucleomodulin BspJ in Brucella's intracellular infection cycles. Methods: Constructed Brucella abortus BspJ gene deletion strain (B. abortus ∆BspJ) and complement strain (B. abortus pBspJ) and studied their roles in the proliferation of Brucella both in vivo and in vitro. Results: BspJ gene deletion reduced the survival and intracellular proliferation of Brucella at the replicating Brucella-containing vacuoles (rBCV) stage. Compared with the parent strain, the colonization ability of the bacteria in mice was significantly reduced, causing less inflammatory infiltration and pathological damage. We also found that the knockout of BspJ altered the secretion of cytokines (interleukin [IL]-6, IL-1β, IL-10, tumor necrosis factor-α, interferon-γ) in host cells and in mice to affect the intracellular survival of Brucella. Conclusions: BspJ is extremely important for the circulatory proliferation of Brucella in the host, and it may be involved in a previously unknown mechanism of Brucella's intracellular survival.

• Asian Journal of Innovation and Policy
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• 제6권3호
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• pp.274-294
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• 2017

While studies have viewed the effect of Chinese talent-attracting programs launched by government since reform and open door policy, little of them has assessed these programs empirically and pertinently. This article intends to assess an important program - the Thousand Youth Talents Program (TYTP). Frist, this paper proposed a transnational migration matrix of the academics to clarify the dynamic mechanism of academic brain gain at the high end. Then, the Kaplan-Meier analysis and Cox regression model are used to empirically analyze the policy effect of TYTP. The results show that, academic ability have double edged impacts on brain gain at the high end, some scholars whose last employer's academic ranking is world's Top100 have stronger willing to return, and the negative effect of academic ranking decreases with time passing; while scholars with a tenure-track position, a tenure position or a permanent position tend to stay overseas, and the hazard rate of staying increases with age. The older scholars have more intentions to go back China, while gender was not a significant factor influencing academic return at the high end. That is, the talent-attracting programs has partly succeeded in bringing back the academics at the high end.

• International Journal of Industrial Entomology and Biomaterials
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• 제13권2호
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• pp.63-72
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• 2006

Parthenogenesis, the development of unfertilized ovum opens new perspectives in silkworm breeding in the development of homozygous breeds. In order to improve induction of artificial parthenogenesis in the excised unfertilized eggs of different breeds of the silkworm, Bombyx mori L., a new method was devised and the results were compared with the routine method. General and specific combining abilities and hybrid vigour of newly developed bivoltine breeds were analyzed utilizing bivoltine breeds viz., $CSR_2,\;CSR_4,\;CSR_{17}\;and\;NB_4D_2$ Estimation of GCA revealed superiority of the breeds, $DNB_1$ for eight characters followed by $DNB_4$ for five characters. Among the testers, $CSR_2$ was found good general combiner for seven characters followed by $CSR_{17}$ for four characters. A great deal of variations was observed among the hybrids studied. Five hybrids namely, $DNB_1{\times}CSR_2,\;DNB_4{\times}CSR_4,\;DNB_4{\times}NB_4D_2,\;DNB_6{\times}CSR_2\;and\;DNB_7{\times}CSR_2$ showed significant SCA effects for 5-6 characters. The hybrid, $DNB_4{\times}CSR_4$ showed its superiority by expressing significant hybrid vigour over BPV for 7 characters. Majority of the hybrids exhibited significant hybrid vigour for survival rate, yield/10,000 larvae by weight, cocoon weight, cocoon shell weight, filament length and denier.

• IMMUNE NETWORK
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• 제13권1호
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• pp.16-24
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• 2013

CTLA-4Ig is regarded as an inhibitory agent of the T cell proliferation via blocking the costimulatory signal which is essential for full T cell activation. To improve applicability, we developed the CTLA-4Ig-CTKC in which the c-terminal lysine had been replaced by cysteine through single amino acid change. The single amino acid mutation of c-terminus of CTLA-4Ig was performed by PCR and was checked by in vitro transcription and translation. DNA construct of mutant form was transfected to Chinese hamster ovary (CHO) cells by electroporation. The purified proteins were confirmed by Western blot and B7-1 binding assay for their binding ability. The suppressive capacity of CTLA-4Ig-CTKC was evaluated by the mixed lymphocyte reaction (MLR) and in the allogeneic pancreatic islet transplantation model. CTLA-4Ig-CTKC maintained binding ability to B7-1 molecule and effectively inhibits T cell proliferation in MLR. In the murine allogeneic pancreatic islet transplantation, short-term treatment of CTLA-4Ig-CTKC prolonged the graft survival over 100 days. CTLA-4Ig-CTKC effectively inhibits immune response both in MLR and in allogeneic islet transplantation model, indicating that single amino acid mutation does not affect the inhibitory function of CTLA-4Ig. CTLA-4Ig-CTKC can be used in vehicle-mediated drug delivery system such as liposome conjugation.

• 한국수정란이식학회지
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• 제21권3호
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• pp.255-262
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• 2006

본 연구는 Open Pulled Straw(OPS)방법에 의해 동결-융해한 돼지 수정란의 체외 생존 능력을 검토하기 위하여 수행되었다. 미성숙 난자의 체외 성숙을 위하여, 돼지 난소는 도축장에서 회수하였으며, 난구세포로 쌓여있는 난자는 직경 $2{\sim}6mm$의 난포로부터 난포액과 함께 흡입에 의하여 회수하였다. 회수된 미성숙 난자의 체외 성숙을 위하여 5 mM hypotaurine, 0.57 mM cysteine, 10% 난포액, 10 IU/ml PMSG 및 10 IU/ml hCG가 함유된 NCSU-23 배양액 내에서 $21{\sim}22$ 시간 배양 후, 호르몬 물질을 제거한 성숙 배양액 내에서 $21{\sim}22$ 시간 동안 추가 배양하였다. 한편 체외 수정을 위하여 동결-융해한 정액은 5.56 mM glucose, 0.33 mM na-pyruvate, 100 IU/ml penicillin, $100 {\mu}g/ml$ streptomycin 및 4 mg/ml BSA가 첨가된 D-PBS 액을 가지고 1,500 rpm에서 10분간 2회 원심분리를 실시하여 세척하였다. 체외 수정을 위한 배양액은 pH $7.2{\sim}7.4$에서 2 mM caffeine과 2 mg/ml BSA가 첨가된 mTBM 배양액을 이용하였다. 체외 수정시 정자의 최종 농도는 $2.5{\times}10^6cells/ml$로 조정하였다. 수정 8시간 후, 체외 발육을 위하여 5.0 mM hypo-taurine, 4 mg/ml BSA 및 10 ng/ml EGF가 첨가된 NCSU- 23액으로 옮겨 7일간 배양을 계속하였다. 그 후 배반포의 여러 단계에서 OPS 법에 의해 동결-보존하였다. 그 결과, 동결-융해 후 형태학적으로 정상적인 수정란의 비율은 초기 배반포(28.3%)보다는 확장 배반포(38.9%)단계에서 동결했을 때 유의적으로 높게 나타났다(p<0.05). 한편, 동결-융해 후 상해를 입은 수정란의 비율은 확장 배반포보다는 초기 배반포 단계에서 동결된 수정란에서 유의적으로 높은 성적을 보였다(p<0.05). 또 다른 실험에서, 수정란의 동결-융해 후 형태학적으로 정상인 수정란을 48시간 추가 배양했을 때, Hatching 된 수정란의 비율은 초기 배반포, 배반포 및 확장배반포기 단계에서 동결-융해한 수정란에서 각각 6.7, 20.0 및 33.3%로 발육 단계가 높을수록 동결-융해 후의 생존율도 높게 나타났다. 본 연구의 결과로부터, 돼지에서 수정란의 동결-융해 후 생존성의 향상을 위해서는 발육 단계가 높은 배반포기 단계에서의 동결이 요구되며 본 연구에서 이용된 OPS 동결 방법이 폭넓게 활용될 것으로 사료된다.

• 한국가금학회지
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• 제48권2호
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• pp.69-80
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• 2021

본 연구는 생산능력이 우수한 신품종 토종 종계를 개발하기 위하여 (주)한협원종이 보유한 원종계(GPS) 4개 계통 934수를 이용하여 4 × 4 이면교배조합(diallel cross-mating) 검정 시험을 실시하였다. 검정 형질로서 외모 형태, 생존율, 체중, 초산일령, 난중 및 산란율을 대상으로 조합별 생산능력, 조합가, 결합능력 및 상반교잡 효과를 분석하였다. 분석 결과, 대부분의 교배조합 개체들의 깃털 색은 황갈색 및 적갈색과 이들 색 간의 혼합 양상을 나타내었다. 전체 조합의 평균 생존율은 86.8±12.3%이고, YH 조합의 생존율이 가장 높았다. 생존율의 조합가는 특정결합능력이 일반결합능력에 비해 상대적으로 크게 영향을 미치는 것으로 나타났고, HY의 특정결합능력이 가장 높게 나타났다. 체중의 경우, 16개의 교배 조합이 유전적 특성에 따라 세 그룹으로 명확히 구분되는 것으로 나타났다. 12주령 체중의 교배조합별 조합가는 계통별 일반결합능력이 두 계통 간의 특정결합능력보다 크게 영향을 미치는 것으로 나타났고, FH 조합에서 가장 높은 조합가가 추정되었다. 산란 형질에 있어 전체 교배조합구의 평균 초산일령은 157일로서 교잡 구가 순계 구보다 빠른 성 성숙을 보였다. 전체 조합의 평균 일계산란율은 69.0±10.9%로서 이들 중 SY 조합이 가장 높은 산란율을 보였다. 산란율의 일반결합능력과 특정결합능력의 추정 범위가 거의 비슷한 값을 나타내고 있으며, 교배조합 간 특정결합능력은 HS 및 FY 조합에서 높게 나타났다. 또한 상반교잡 효과는 대부분의 조합에서 S와 Y를 모(母)로 사용하였을 때 자손들의 산란능력이 상대적으로 높게 나타났다. 이상의 결과에 따라 신품종토종닭 종계로써 부계는 체중이 우수하면서 상대적으로 생존율이 양호한 FH나 HF 조합이, 모계는 산란능력이 우수하며 적절한 체중을 지닌 FY, FS, HY 및 SY 조합이 바람직한 것으로 사료된다.

• 한국수산과학회지
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• 제53권2호
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• pp.191-202
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• 2020

We evaluated the effects of dietary supplementation of phytosterol on the growth, feed utilization, immunity, digestibility, wound healing ability and disease resistance of olive flounder Paralichthys olivaceus. We conducted two consecutive feeding trials at different growth stages of the fish: EXP-1 (68.9 g) and EXP-2 (16.5 g). The experimental diets were supplemented with graded levels of phytosterol (1% ecdysteroid extracted from Achyranthis radix) at 0, 0.025, 0.05, 0.1, 0.2 and 0.4% (designated as Con, PHY0.025, PHY0.05, PHY0.1, PHY0.2 and PHY0.4, respectively). Dietary phytosterol did not significantly affect growth and cholesterol concentration. Feed utilization was higher in fish fed phytosterol-supplemented diets than in fish fed the control diet. Dietary phytosterol increased innate immunity and digestibility of protein and dry matter. Wound healing ability was also increased by the phytosterol supplementation. The survival against Edwardsiella tarda challenge was higher in fish fed low-phytosterol diets than in fish fed the control diet. The optimum dietary level of phytosterol seems to be approximately 0.05%. The results in this study indicate that the phytosterol could be used as a functional supplement in diets to improve feed utilization, immunity, digestibility and wound healing ability of olive flounder.