• 한국가축번식학회지
• /
• 제4권1호
• /
• pp.75-82
• /
• 1980

This experiment was carried out to improve a simple and effective procedure of egg transfer which is considered to be the most useful technique for the improvementand proliferation of domestic animals. Several experiment procedures such as superovulation, surgical recovery of ovulated egg, in vitro capacitation of ejaculated spermatozoa, in vitro fertilization and culture of embryo were conducted. The results obtained in this experiment were summarized as follows: 1. In rabbits treated with PMS in combination with estradiol and HCG, 10 to 43 eggs were obtained in one rabbit and the average ovulation number of 20 rabbits was 21 eggs. 2. Six to 24 eggs (average 13 eggs) were recovered from the removed oviducts by the methods of flushing technique and the average recovery rate of 20 rabbits was 61.9 percent. 3. Most rabbit spermatozoa ejaculated by artificial vagina were capacitated in vitro by the culture of the spermatozoa with PBI medium at 37$^{\circ}C$ for 4 hours after removal of seminal plasma. 4. Normal fetilization following in vitro fetilization was observed in 88 (42.7%) of 206 eggs. 5. The number of eggs developed to 2-, 4-, and 8-cell stage following in vitro culture with PBI medium at 37$^{\circ}C$ was 26 (70.3%), 20 (54.1%) and 17 (45.9%) of 37 eggs used for in vitro culture.

• Fisheries and Aquatic Sciences
• /
• 제16권3호
• /
• pp.177-185
• /
• 2013

The development of species-specific fish cell lines has become a valuable tool for biological research. In recent years, marine medaka Oryzias dancena has been recognized as a good experimental model fish but there are no reports of establishment of cell lines from this fish. In this study, two cell lines from O. dancena blastula embryos were established from 41 total trials (4.9%). The two cell lines displayed typical in vitro morphology and have been cultured for >121 passages, which corresponds to 293 days. The doubling times of the cell lines were 29.84 and 28.59 h, respectively, and both possessed the potential to expand in a clonal manner, albeit with significant differences between the two cell lines. The absence of any of the four main medium supplements; i.e., fish serum, fetal bovine serum, basic fibroblast growth factor, and medaka embryo extract, significantly inhibited growth. The proportion of cells possessing normal chromosome number was 45% and 46.7% of the cell lines, respectively. Taken together, two cell lines that proliferate continuously were established from marine medaka and these cell lines may provide a basic tool for characterizing the unique features of this fish species.

• Bulletin of the Korean Chemical Society
• /
• 제34권11호
• /
• pp.3405-3409
• /
• 2013

The activation of heat shock factor 1 (HSF1) can be induced by the changes in environmental pH, but the mechanism of HSF1 activation by acidification is not completely understood. This paper reports that a low pH (pH~6.0) can trigger human HSF1 activation. Considering the involvement of the imidazole group of histidine residues under acid pH stress, an in vitro EMSA experiment, Trp-fluorescence spectroscopy, and protein structural analysis showed that the residue, His83, is the essential for pH-dependent human HSF1-activation. To determine the roles of His83 in the HSF1-mediated stress response affecting the cellular acid resistance, mouse embryo fibroblasts with normal wild-type or mutant mouse HSF1 expression were preconditioned by heating or pH stress. The results suggest that His83 is essential for HSF1 activation or the HSF1-mediated transcription of heat shock proteins, in protecting cells from acid pH stress.

• 한국동물학회지
• /
• 제20권2호
• /
• pp.109-122
• /
• 1977

양서류 수정난의 식물반구를 제 1난할 전에 자외선 조사를 하면 신경관 형성에 독특한 변형을 유발한다. 자외선에 대한 감응도는 수정에서 제 1난면이 나타나기까지의 2/3시기에 급격히 저하된다. 주사 전자현미경 사진은 자외선을 받은 배아의 표피세포들의 크기가 감소된 것을 보여주고 있다. 그러나 외배엽 교환이식 실험은 자외선을 받은 배아의 외배엽이 아직도 완전히 정상적인 신경조직과 표피를 형성할 수 있는 능력을 보유하고 있음을 나타내고 있다. 위의 사실들은 낭배기간중 함입능력의 저하와 일차형성체의 유도능력의 감퇴와 관련시켜 설명하였다.

• Journal of Ginseng Research
• /
• 제23권3호
• /
• pp.148-163
• /
• 1999

The efficacy of three auxins, viz. 2,4-0, NAA and dicamba, were compared for the induction of somatic embryogenesis in American ginseng (Panax quinquefolium L.). Somatic embryos (SEs) formed on ginseng cotyledonary, zygotic embryo and shoot explants after 8 weeks of induction by the auxin stimuli. Significantly more somatic embryos were induced by culture of any of the ginseng explants on media supplemented with $5{\mu}M$ 2,4-0 than any other auxin treatment. Shoots derived from somatic embryos had the greatest regenerative potential and zygotic embryos the least. Explants generated from green (unstratified) seeds gave similar or higher frequency of embryogenesis as the explants derived from stratified seeds. Histological and SEM studies confirmed that the regenerimts were somatic embryos. Somatic embryos germinated and developed into normal plants in $3\~6$ months. About $10\%$ of plantlets from second generation SEs formed flowers within 10 weeks, particularly on media supplemented with $GA_3$ The development of a regeneration system for ginseng through somatic embryogenesis is a necessary first step for mass propagation and genetic improvement of American ginseng.

• Journal of Korean Neurosurgical Society
• /
• 제64권3호
• /
• pp.329-339
• /
• 2021

It has been recognised for over a century that the events of gastrulation are fundamental in determining, not only the development of the neuraxis but the organisation of the entire primitive embryo. Until recently our understanding of gastrulation was based on detailed histological analysis in animal models and relatively rare human tissue preparations from aborted fetuses. Such studies resulted in a model of gastrulation that neurosurgeons have subsequently used as a means of trying to explain some of the congenital anomalies of caudal spinal cord and vertebral development that present in paediatric neurosurgical practice. Recent advances in developmental biology, in particular cellular biology and molecular genetics have offered new insights into very early development. Understanding the processes that underlie cellular interactions, gene expression and activation/inhibition of signalling pathways has changed the way embryologists view gastrulation and this has led to a shift in emphasis from the 'descriptive and morphological' to the 'mechanistic and functional'. Unfortunately, thus far it has proved difficult to translate this improved knowledge of normal development, typically derived from non-human models, into an understanding of the mechanisms underlying human malformations such as the spinal dysraphisms and anomalies of caudal development. A paediatric neurosurgeons perspective of current concepts in gastrulation is presented along with a critical review of the current hypotheses of human malformations that have been attributed to disorders of this stage of embryogenesis.

• 한국발생생물학회:학술대회논문집
• /
• 한국발생생물학회 2003년도 제3회 국제심포지움 및 학술대회
• /
• pp.29-48
• /
• 2003

It is remarkable that nuclear transfer using differentiated donor cells can produce physiologically normal cloned animals, but the process is inefficient and highly prone to epigenetic errors. Aberrant patterns of gene expression in clones contribute to the cumulative losses and abnormal phenotypes observed throughout development. Any long lasting effects from cloning, as revealed in some mouse studies, need to be comprehensively evaluated in cloned livestock. These issues raise animal welfare concerns that currently limit the acceptability and applicability of the technology. It is expected that improved reprogramming of the donor genome will increase cloning efficiencies realising a wide range of new agricultural and medical opportunities. Efficient cloning potentially enables rapid dissemination of elite genotypes from nucleus herds to commercial producers. Initial commercialization will, however, focus on producing small numbers of high value animals for natural breeding especially clones of progeny-tested sires, The continual advances in animal genomics towards the identification of genes that influence livestock production traits and human health increase the ability to genetically modify animals to enhance agricultural efficiency and produce superior quality food and biomedical products for niche markets. The potential opportunities in animal agriculture are more challenging than those in biomedicine as they require greater biological efficiency at reduced cost to be economically viable and because of the more difficult consumer acceptance issues. Nevertheless, cloning and transgenesis are being used together to increase the genetic merit of livestock; however, the integration of this technology into farming systems remains some distance in the future.

• 한국균학회소식:학술대회논문집
• /
• 한국균학회 2014년도 추계학술대회 및 정기총회
• /
• pp.25-25
• /
• 2014

Three species of Fusarium, F. fujikuroi, F. verticillioides and F. proliferatum, are known to be associated with bakanae disease of rice [1, 2]. F. fujikuroi infects rice flowers and survive in endosperm and embryo of the seeds. Infected seed is an important source of primary inoculum of pathogens [3]. Seeds of rice (Oryza sativa cv. Boramchan) collected from bakanae-infected field were found to be 96% infected with Fusarium sp., 52% with F. fujikuroi, 42% with F. verticillioides, and 12% with F. proliferatum as determined by incubation method and species-specific PCR assays. F. fujikuroi was detected at lemma/palea, endosperm and embryo whereas F. verticillioides and F. proliferatum were recovered only from lemma/palea by means of component plating test. Seed disinfection methods have been developed to control bakanae disease and prochloraz has been most widely used for rice seeds. Two chemicals formulated with prochloraz (PC 1) and prochloraz + hexaconazole (PC 2) that inhibit biosynthesis of ergosterol strongly reduced the incidence of Fusarium spp. on selective media to 4.7% and 2.0%, respectively. Disease symptoms of rice seedlings in nursery soil were alleviated by chemical treatment; seedlings with elongated leaves or wide angle between leaf and stem were strikingly reduced from 15.6 to 3.2% (PC 1) and 0 (PC 2), stem rots were reduced from 56.9 to 26.2% (PC 1) and 32.1% (PC 2), and normal seedling increased from 0.4 to 13.3% (PC 2). Prochloraz has some disadvantages and risks such as the occurrence of tolerant pathogens [4] and effects on the sterol synthesis in animals and humans [5]. For these reasons, it is necessary to develop new disinfection method that do not induce fungal tolerance and are safe to humans and animals. Chlorine dioxide ($ClO_2$), that is less toxic, produces no harmful byproducts, and has high oxidizing power, has been reported to be effective at disinfection of several phytopathogenic fungi including Colletotrichum spp. and Alternaria spp. [6]. Gaseous $ClO_2$ applied to rice seeds at a concentration of 20 ppm strongly suppressed mycelial growth of Fusarium fujikuroi, F. verticillioides and F. proliferatum. The incidence of Fusarium spp. in dry seed with 8.7% seed moisture content (SMC) tended to decrease as the concentration of $ClO_2$ increased from 20 to 40 ppm. Applying 40 ppm $ClO_2$ at 90% relative humidity, incidence was reduced to 5.3% and resulted in significant reduction of disease symptoms on MS media. In nursery soil, stem rot was reduced from 56.9 to 15.4% and the number of normal seedlings increased from 0.4 to 25.5%. With water-soaked seeds (33.1% SMC) holding moisture in the endosperm and embryo, the effectiveness of disinfection using $ClO_2$ increased, even when treated with only 20 ppm for four hours. This suggests that moisture was a key element for action of $ClO_2$. Removal of the palea and lemma from seeds significantly decreased the incidence of Fusarium spp. to 3.0%. Seed germination appeared to decrease slightly by water-soaking at $30^{\circ}C$ because of increased SMC and by physical damage of embryos from hulling. These results indicate that the use of gaseous $ClO_2$ was effective as a means to disinfect rice seeds infected with Fusarium spp. and that moisture around the pathogens in the seed was an important factor for the action of $ClO_2$. Further investigations should be conducted to ascertain the best conditions for complete disinfection of Fusarium spp. that infect deep site of rice seeds.

• 한국수정란이식학회지
• /
• 제20권2호
• /
• pp.177-184
• /
• 2005

본 연구는 정상 및 저수태 한우에 rbST를 투여하였을 때 수태 및 분만율에 미치는 영향을 조사하기 위하여 수행하였다. 시험축은 성빈 한우 383두와 임상적으로는 정상이나 3회 이상 수정시켜도 수태가 되지 않는 저수태 한우 79두, 총 462두를 시험에 공시하였다. 실험을 수행하기 위한 시험구 배치는 5개의 처리구, 즉 T1(무처리, 2ml의 생리 식염수), T2(rbST 250mg 수정시 1회 미근부에 투여), T3(rbST 250mg: 수정시 및 수정후 $10\~14$일째 2회 투여), T4(rbST 500 mg: 수정시 1회 투여) 및 T5(rbST 500mg: 수정시 및 수정후 $10\~14$일째 2회 투여)로 나누어 시험을 실시하였다. 그리고 호르몬과 병행 처리구는 Day 0일에 GnRH 100 ug/cow를 견갑부에 피하주사하고 Day 7일째 $PGF_2{\alpha}\;25mg/cow$를 주사하여 황체를 퇴행시키고, Day 9일째 GnRH 100ug/cow를 주사하여 배란 동기화를 유도하여 시험에 공시하였다. 1. 정상 한우에 인공수정시 rbST를 T1, T2, T3, T4 및 T5로 처리하였을 때, 1회 수정 수태율은 대조구$(52.4\pm9.72\%)$에 비하여 $T2(67.5\pm18.48\%)$에서 높은 것으로 나타났고, 저수태우에서는 대조구$(39.3\pm12.89\%)$보다 $T4(63.3\pm5.77\%)$에서 유의적으로 높은 수태율을 나타냈다.(p<0.05). 또한, 정상 한우의 분만율에 있어서는 처리구간 유의적인 차이가 인정되지 않았지만, 저수태우에서는 $T4(46.7\pm11.55\%)$에서 유의적으로 높은 성적을 나타냈다(p<0.05). 2. Ovsynch 방법으로 발정을 유기하여 인공수정시 rbST를 T1, T2, T3, T4 및 T5로 처리하였을 때, 1회 수정 수태율은 대조구에 비하여 T2에서 $12.5\%$가 높은 것으로 나타났고, 저수태우에서는 $T4(80.0\%)$에서 유의적으로 높은 수태 율을 나타냈다(p<0.05). 3. 정상 한우에 인공수정시 rbST를 T1, T2, T3, T4 및 T5로 각기 처리하였을 때, 임신 기간은 평균 $282.7\~284.8$일이었고, 또한 생시체중의 비교는 평균 $25.1\~25.9kg$으로서 처리 구간 유사한 결과를 보였다. 그러나, 송아지의 암수 성비는 T4 처리구(18두 vs. 9두)를 제외한 모든 처리구에서 유사한 경향을 보였다. 그리고, 저수태 한우의 평균 임신 기간은 $280.4\~289.3$일로서 정상우와 비교했을 때 비슷한 결과를 보였고, 또한 생시 체중의 조사 결과에서도 평균 체중이 $23.0\~26.6kg$으로서 각 처리구간에도 유의성은 없었다. 송아지의 암$\cdot$수의 성비는 T4 처리구(2두 vs. 8두)를 제외한 모든 처리구에서 유사하게 나타났다. 결론적으로, 본 연구에서는 정상 및 저수태 성빈 한우에 rbST를 투여한 후 수태율과 분만율을 조사한 결과 인공수정시 정상우에서는 rbST를 250mg 1회 투여, 그리고 저수태 한우에 있어서는 rbST를 500mg을 인공수정시 1회 투여하였을 때가 다른 처리구에서 보다 우수한 결과를 나타내었다. 따라서 인공수정시 일정량의 rbST투여는 한우의 수태 및 분만율을 향상시키는 것으로 사료된다.

• Reproductive and Developmental Biology
• /
• 제35권1호
• /
• pp.33-45
• /
• 2011

Heat shock protein 90 (Hsp90) is ATPase-directed molecular chaperon and affects survival of cancer cell. Inhibitory effect of Hsp90 by inducing cell cycle arrest and apoptosis in the cancer cell was reported. However, its role during oocyte maturation and early embryo development is very insufficient. In this study, we traced the effects of Hsp90 inhibitor, 17-allylamino-17-demethoxygeldanamycin (17-AAG), on meiotic maturation and early embryonic development in pigs. We also investigated several indicators of developmental potential, including structural integrity, gene expression (Hsp90-, cell cycle-, and apoptosis-related genes), and apoptosis, which are affected by 17-AAG. Then, we examined the roles of Hsp90 inhibitor on viability of primary cells in pigs. Porcine oocytes were cultured in the NCSU-23 medium with or without 17-AAG for 44 h. The proportion of GV arrested oocytes was significantly different between the 17-AAG treated and untreated group (78.2 vs 34.8%, p<0.05). After completion of meiotic maturation, the proportion of MII oocytes was lower in the 17-AAG treated group than in the control group (27.9 vs 71.0%, p<0.05). After IVF, the percentage of penetrated oocytes was significantly lower in the 17-AAG treated group (25.2%), resulting in lower normal pronucleus formation (2PN of 14.6%). Therefore, the inhibition of meiotic progression by Hsp90 inhibitor played a critical role in fertilization status. Porcine embryo were cultured in the PZM-3 medium with or without 17-AAG for 6 days. In result, significant differences in developmental potential were detected between the embryos that were cultured with or without 17-AAG. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) showed that the number of containing fragmented DNA at the blastocyst stage increased in the 17-AAG treated group compared with control (7.5 vs 4.4, respectively). Blastocysts that developed in the 17-AAG treated group had low structural integrity and high apoptotic nuclei than those of the untreated control, resulting in decrease the embryonic qualities of preimplantation porcine blastocysts. The mRNA expressions of cell cycle-related genes were down-regulated in the 17-AAG treated group compared with control. Also, the expression of the pro-apoptotic gene Bax increased in 17-AAG treated group, whereas expression of the anti-apoptotic gene Bel-XL decreased. However, the expression of ER stress-related genes did not changed by 17-AAG. Cultured pESF cells were treated with or without 17-AAG and used for MIT assay. The results showed that viability of pESF cells were decreased by treatment of 17-AAG ($2{\mu}M$) for 24 hr. These results indicated that 17-AAG decreased cell proliferation and increased cell death. Expression patterns Hsp90 complex genes (Hsp70 and p23), cell cycle-related genes (cdc2 and cdc25c) and apoptosis-related genes (Bax and Bcl-XL) were significantly changed by using RT-PCR analysis. The spliced form of pXbp-1 product (pXbp-1s) was detected in the tunicamycin (TM) treated cells, but it is not detected in 17-AAG treated cells. In conclusion, Hsp90 appears to play a direct role in porcine early embryo developmental competence including structural integrity of blastocysts. Also, these results indicate that Hsp90 is closely associated with cell cycle- and apoptosis-related genes expression in developing porcine embryos.