This study was carried out to examine splitting, developmental capacity and rapid freezing of blastomeres separated from 2-, 4-, 8-cell and morula from porcine embryos. The results obtained in this study were summerized as follows : 1. The successful splitting rate by pronase was 85.7% in 2-cell embryos(average splitting rate, 68.0%), and by manipulator was 76.6% and 74.3% in 2- and 4-cell embryos. 2. The developmental capacity rates of splitted embryos by the pronase treatment were 24.1%, 20.4%. 25.5% and 26.6% in 2-, 4-, 8-cell and morula, and by manipulator were 36.4%, 39.5%, 36.1% and 41.9%, respectively. 3. The successful results of in vitro culture after frozen-thawed of splitted embryos were 16.1%(glycerol) in 2-cell, 16.7%(DMSO) in 4-cell and 27.6%(ethyleneglycol) in morula, respectively.
Yang, Insook;Son, Yeri;Shin, Jae Hoon;Kim, Il Yong;Seong, Je Kyung
BMB Reports
/
v.55
no.8
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pp.401-406
/
2022
Ahnak, a large protein first identified as an inhibitor of TGF-β signaling in human neuroblastoma, was recently shown to promote TGF-β in some cancers. The TGF-β signaling pathway regulates cell growth, various biological functions, and cancer growth and metastasis. In this study, we used Ahnak knockout (KO) mice that underwent a 70% partial hepatectomy (PH) to investigate the function of Ahnak in TGF-β signaling during liver regeneration. At the indicated time points after PH, we analyzed the mRNA and protein expression of the TGF -β/Smad signaling pathway and cell cycle-related factors, evaluated the cell cycle through proliferating cell nuclear antigen (PCNA) immunostaining, analyzed the mitotic index by hematoxylin and eosin staining. We also measured the ratio of liver tissue weight to body weight. Activation of TGF-β signaling was confirmed by analyzing the levels of phospho-Smad 2 and 3 in the liver at the indicated time points after PH and was lower in Ahnak KO mice than in WT mice. The expression levels of cyclin B1, D1, and E1; proteins in the Rb/E2F transcriptional pathway, which regulates the cell cycle; and the numbers of PCNA-positive cells were increased in Ahnak KO mice and showed tendencies opposite that of TGF-β expression. During postoperative regeneration, the liver weight to body weight ratio tended to increase faster in Ahnak KO mice. However, 7 days after PH, both groups of mice showed similar rates of regeneration, following which their active regeneration stopped. Analysis of hepatocytes undergoing mitosis showed that there were more mitotic cells in Ahnak KO mice, consistent with the weight ratio. Our findings suggest that Ahnak enhances TGF-β signaling during postoperative liver regeneration, resulting in cell cycle disruption; this highlights a novel role of Ahnak in liver regeneration. These results provide new insight into liver regeneration and potential treatment targets for liver diseases that require surgical treatment.
Objectives: This study was carried out to evaluate the effects of embryonic stage, cryoprotectant, and freezing-thawing method on the rates of survival and development of the cryopreserved mouse early embryo and finally to establish the cryopreservation method of surplus embryos obtained during assisted reproductive technology (ART). Materials and Methods: Two to eight cell embryos were obtained from oviducts of mated $F_1$ hybrid female mice superovulated by pregnant mare's serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG). Two-step 1,2-propanediol (PROH), dimethylsulfoxide (DMSO) and 4-step PROH DMSO were used as cryoprotectant and dehydration and rehydration method of embryos, and slow-cooling or rapid-cooling method was used as frozen program. The survival rates of embryos were measured after thawing and rehydration, and the developmental rates of embryos were compared and observed during culturing embryos for 24, 48, 72, 96 hrs. Results: As for the survival and development rates of embryos according to embryonic stage, the survival rate of 2 cell stage in PROH and DMSO was significantly higher than 4-8 cell (64.5% versus 62.1 %,79.7% versus 73.2%) (p<0.01, p<0.01), but the development rates of 4-8 cell embryos in PROH and DMSO were significantly higher than 2 cell embryos for whole culture period (p<0.01) and the development rates of 4-8 cell embryos in PROH were significantly higher than 2 cell embryos in DMSO (p<0.01). As for the survival and development rates of embryos according to cryoprotectant, the survival rate of 2 cell embryo in DMSO was significantly higher than that in PROH (74.4% versus 64.5%) (p<0.01), whereas the development rate of embryos was not differ till 24 hrs. The developmen1 rate from morular to hatching blastocyst, however, was significantly higher in PROH than in DMSO during 48 hr (p<0.01). The survival rate of 4-8 cell embryo was 62.1% in PROH and 73.2% in DMSO. The development rates of embryo in PROH were significantly higher for whole culture periods (p<0.01, 0.05). In respect to the effect of freezing and thawing program on the survival and development rates of embryos, method of slow cooling and rapid thawing was more effective than that of rapid cooling and rapid thawing. Conclusions: The survival rate of embryo in 2 cell stage was higher than in 4-8 cell stage, and PROH appears more effective cryoprotectant than DMSO because PROH showed better development rates of embryos in 2 and 4-8 cell stage. Moreover, slow cooling and rapid thawing method was considered as the best cryopreservation program.
Kim, Tae-Hee;Yuh, In-Suh;Park, In-Chul;Cheong, Hee-Tae;Kim, Jong-Taek;Park, Choon-Keun;Yang, Boo-Keun
Journal of Embryo Transfer
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v.29
no.2
/
pp.141-148
/
2014
Quercetin and genistein, plentifully present in fruits and vegetables, are flavonoid family members that have antioxidative function and plant-derived phytoestrogen activity. The antioxidative effects of quercetin and genistein on boar sperm characteristics and in vitro development of IVF embryo were investigated. The sperm motility was increased by addition of genistein $50{\mu}M$ for 6 hr incubation compared to control (p<0.05). The sperm viability was increased by addition of quercetin 1 and $50{\mu}M$ and genestein 1 and $50{\mu}M$ for 3 hr incubation. In addition, the sperm viability seemed to be increased dose-dependantly by addition of quercetin or genistein 1 and $50{\mu}M$, respectively (p<0.05). The membrane integrities were not increased by quercetin or genistein treatments for 3 hr or 6 hr incubation period except for quercetin $1{\mu}M$ for 3 hr incubation. In mitochondrial activities, addition of quercetin $50{\mu}M$ for 6 hr incubation increased mitochondrial activity but decreased at $100{\mu}M$ concentration compared with control (p<0.05). When porcine IVF embryos were cultured in PZM-3 medium supplemented with low concentrations of quercetin ($1{\sim}10{\mu}M$), the developmental rates to morula and blastocyst increased but significantly decreased at high concentrations of quercetin ($25{\sim}50{\mu}M$). The highest developmental rate to blastocysts among all concentrations of quercetin was shown at quercetin $10{\mu}M$ (p<0.05). The developmental rates to morula or blastocysts at low ($0.01{\sim}1{\mu}M$) and high ($5{\sim}10{\mu}M$) concentrations of genistein were not significantly different among all treatment group and genistein did not affect on IVF embryo development. These results suggest that quercetin and genistein seem to have positive effects at certain concentrations on sperm characteristics such as motility, viability and mitochondrial activity. In addition, low concentrations of quercetin (1, 5 and $10{\mu}M$) in this experiment, seem to have beneficial effect on porcine IVF embryo development but genistein did not affect on it at all given concentrations ($0.01{\sim}10{\mu}M$).
In this study, we investigated the effects of three kinds of culture medium (Charles and Rosenkrans; CRlaa, Tyrode's; TALP, synthetic oviduct fluid: SOF), insulin transferrin + selenium complex (ITS), macromolecules(polyvinyl alcohol: PVA, fetalb-ovine serum: FBS) and NaCl on the development of early bovine embryos. In experiment 1, there were no differences in embryo development among three kinds of embryo culture medium (CR $l_{aa}$ , TALP, SOF). In experiment 2, BSA, FBS and PVA were added each in TALP as macromolecule sources. The developmental rates of embryos in BSA or FBS added TALP were significantly higher than in PVA added one (p〈0.01), but there was no difference between BSA and FBS added groups. In experiment 3, bovine embryos were cultured in TALP with the following supplements: BSA alone(1, 3 or 8 mg/ml, each) or BSA(1, 3 or 8 mg/ml, each)+ITS (10$\mu\textrm{g}$/m1 insulin, 5 $\mu\textrm{g}$/ml transferrin, 5 ng/ml selenium). In higher concentration of BSA and ITS supplemented groups, the developmental rates over compacted morula were higher than others, but there was a significant effect of ITS only in 1 mg/ml of BSA added group (p〈0.05). In experiment 4, the effect of reduced concentration of NaCl was evaluated. The developmental rate over compacted morula in the medium containing 90 mM of NaCl was higher than in 114 mM group (p〈0.05). In conclusion, BSA could be used as a macromolecule source in bovine embryo culture, and ITS, as a serum substitute, could be used for improving of embryonic development. Also, reduction of NaCl concentration from 114 mM to 90 mM may improve the development of bovine embryos.bryos.
Electrical treatment has been widely used for porcine oocytes activation. However, developmental rates following electrical activation of porcine oocytes is relatively inefficient compared to other domestic animals. To investigate the effects of porcine oocytes on combined activation by both chemical and electrical treatment, in-vitro matured oocytes were activated by combined cycloheximide and electrical pulses treatment. Cumulus-free oocytes were exposed with NCSU-23 medium containing cycloheximide $(10{\mu}g/ml)$ for 0, 5, 10, 20, 30 min and then activated by electrical pulse treatment and cultured in PZM-3 for 8 days. Also effects of exposure to $6.25{\mu}M$ calcium ionophore for 2 min for cumulus-free oocytes were tested. The percentage of blastocyst formation in 10 min exposure to $10{\mu}g/ml$ cycloheximide and electrical pulse treatment was significantly increased (P<0.05) than in the control group. And exposure to $6.25{\mu}M$ calcium ionophore for 2 min with $10{\mu}g/ml$ cycloheximide for 10min and electrical pulse treatment significantly increased (P<0.05) the percentage of blastocyst developmental rates than the control group. In conclusion, activation by combined cycloheximide and electrical stimulation treatment promoted the subsequent development of porcine oocytes and improved the subsequence blastocyst development.
Kim, Young-Soo;Do, Yong-Hyun;Kim, Su-Yun;Chang, Young-Jin
Development and Reproduction
/
v.14
no.2
/
pp.59-63
/
2010
This study was performed to examine the influence of water temperature on egg developmental speed for determining the required time and optimum water temperature for hatching of olive flounder Paralichthys olivaceus eggs. The fertilized eggs were collected from the naturally spawned adults in November 2007. The eggs were randomly divided into 6 groups of temperature (5, 10, 15, 20, 25 and $30^{\circ}C$) and transferred in $1{\ell}$ beaker, respectively. The fertilized eggs of the olive flounder did not hatched at $5^{\circ}C$ and $30^{\circ}C$ and hatching rates at 10, 15, 20 and $25^{\circ}C$ were 3, 12, 25 and 50%, respectively. The relationships between the water temperature (T, $^{\circ}C$) and required time (1/t, hour) from egg to each developmental stage were given as follows ; Blastula: 1/t=0.0208T-0.0951 ($r^2$=0.8593) Kupffer's vesicle: 1/t=0.0052T-0.0176 ($r^2$=0.9819) Myotome: 1/t=0.0034T-0.0172 ($r^2$=0.8508) Hatching: 1/t=0.0016T-0.0068 ($r^2$=0.9915) Biological minimum temperature in egg development was calculated to be $4.3^{\circ}C$.
The study was carried out to investigate the effects of morphology, reproductive cycle, incubation time and activation of oocytes in vitro maturation of canine oocytes and development of canine IVM/IVF embryos. The results were summarized as follows: 1. The developmental rates to 16 cells of fresh, salts and 4$^{\circ}C$-stored oocytes with and without cumulus cells were 14.3%, 5.0% and 7.5%, 2.8% and 5.7%, 0.0%, respectively. The rate of oocytes with cumulus cells(5.7%~14.3%) was higher than that of denuded oocytes(0.0%~5.0%). 2. The developmental rate to If cells of in vitro cultured oocytes recovered from ovaries collected at different stages of the reproductive cycle were 0.0%, 10.7%, 1.5%, respectively. 3. The developmental rate to 16 cells of fresh oocytes with cumulus cell cultured for 24, 32 and 48 hrs in $CO_2$ incubator were 0.0%, 5.3%, 11.8%, respectively. The rate of oocytes cultured for 48 hrs was higher than that oocytes cultured for 24 and 32 hrs. 4. The development to If cells treated activation and non-activation oocytes were 15.0%, 6.7%, respectively. The rate of oocytes treated activation was higher than that oocyte treat non-activation.
Objective : This study aimed to acquire activities of daily living (ADL) skills through activity analysis and forward chaining in children with developmental disabilities. Methods : In this study, the performance of children with developmental disabilities was guided stepwise using a changing criterion design. The intervention was conducted in forward chaining after the therapist analyzed the activities of three tasks (shoes, shorts, and short-sleeved T-shirts) set as the Canadian Occupational Performance Measure (COPM). The performance rate at each stage of the three tasks was used as an independent variable, and COPM performance and satisfaction scores before and after the intervention were set as dependent variables. Results : The task performance rates of children wearing shoes, shorts, and short-sleeved T-shirts improved over time. Even at home, the scores for performance and satisfaction of all three tasks increased. Conclusion : Hopefully, activity analysis and behavioral chaining methods will be used not only for ADL but also for various tasks in children with developmental disabilities who have difficulty acquiring tasks.
It is widely recognized that the embryonic or fetal loss after breeding is common in the cattle and that it is an important factor affecting reproductive efficiency. The causes of this loss have been subject of extensive researches and the results indicate that the embryonic mortality may he primary factor responsible for low pregnancy rates in non-embryo transfer bovine populations as well as embryo transfer programs. However, it's causes are still not clearly understood. The embryonic mortality or pregnancy rate has been influenced by various embryonic and maternal effects related to genetic and environmental factors. The timing and extent of embryonic mortality vanes greatly according to authors and estimating methods, because it is difficult to make direct measurements. The major important factors that may influence the embryonic losses or pregnancy rates after embryo transfer can be summeirized. 1.When an embryo is transferred to unmated recipients, the contralateral transfer to corpus luteum results in a lower survival rate than ipsilateral deposition. When the embryos are transferred for the production of twin calves, their survivals and twin pregnancies have quite inconsistent according to the transfer methods either to the unmated-synchronized or already mated recipients and more works are needed to accurrately clarify the previous results. 2.Although embryos can be cultured in vitro some hours without the great declines in pregnancy rates, the rates differ markedly among culture times and media but may be improved by co-transfer systems. 3.Embryo developmental stages and quality grades clearly affect the survival rate following freezing and the pregnancy rate after transfer and the selection of embryos without chromosome abnormalities and of high fertile semen may also be considered to increase the pregnancy rates. 4.Many researches have attempted to relate the plasma progesterone levels to pregnancy rates and others have done either direct progesterone supplementation or luteal stimulation by hCG treatment in order to increase the pregnancy rates. However, these effects on pregnancy rates are inconsistent and also contradictory. 5.The asynchrony between donors or embryos and recipients may he a major cause of embryo death and low pregnancy rate and the sensitivity to uterine asynchyony differs in according to the quality and stages of embryos. 6.The extremes of poor or over nutrition during early pregnancy in the recipients are detrimental to the survival of embryos and the good body condition is required to prevent a reduejion of pregnancy rates. The uterine pathogens in embryonic mortality or fertility have been questioned but the infection of C.pyogenes and Campylobacter fetus is still important pathogens. 7.The heat stress during early pregnancy may reduce conceptus weight and possibly increase the embryonic mortality.
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