The objective of this study was to investigate response of corpus luteum, recovery rate of embryos and production of transferable embryos according to superovulation by PEG 30% FSH in Hanwoo. Cows were selected as recipient, subsequent were superovulated with a total of 400 mg NIH-FSH-P1(Folltropin-V, Canada) given by one shot subcutaneously. At the time of five days after Folltropin injection, 25mg of a PGF$_2$a was injected and cows were inseminated 12 and 24h after the onset of estrus. Seven days after insemination, embryos were collected non-surgically and were cryopreserved by direct transfer methods. The results are summarized as follows : 1. Response of corpus luteum following the superovulation in Hanwoo, right ovary were 52.8%(271/513) and left ovary were 47.1%(242/513), respectively (P<0.05). 2. Recovery rate of embryos following the number of corpus luteum were 83.0%(426/513). 3. Mean number of embryos recovered and transferable embryos were 7.74 and 6.43, respectively (P<0.05). 4. In the total number of transferable embryos per flush were collected 6.4 and all saved transferable embryos were 355.
Objective: To determine the effects of leukemia inhibitory factor (LIF) on embryonal development in in vitro culture. Methods: This is designed in vitro model using eggs from mouse. The eggs from mouse were assigned 29 for control group, 53 for 20 ng/ml of LIF, 88 for 40 ng/ml of LIF, 68 for 80 ng/ml of LIF respectively for in vitro fertilization. And 26 fertilized eggs at 2 cell stage from mouse also were assigned. The mouse embryos of all groups were cultured in medium supplemented with LIF in different concentrations, whereas the eggs in control group was cultured in medium without supplement of LIF. Results: At 72 hours culture of eggs from in vitro fertilization, there was a slight increas in rate of embryonal development to morula in both LIF-20 and LIF-40 as results of 64.15% and 75% respectively, while 42.65% in inferior rate of LIF-80, compare with 51.72% in control group. But the difference between these each groups were not significant in statistically ($p{\le}0.05$). And after 96 hours culture of eggs, the rates blastocyst formation was significantly higher in both LIF-20 and LIF-40 as 56.6% and 63.63% than those in control and LIF-80 as 44.83% and 35.29% respectively. On culturing eggs from in vivo fertilization, the rates of blastocyst formation was significantly not only higher as 85% and 81.81% respectively in medium supplemented with LIF-40 and LIF-80 than 42.3% in LIF-20 but also embryonal cell viability were remakedly improved at 96 hours after culture. Conclusion: The LIF in low dose is embryotrophic, but LIF in high dose is embryotoxic on eggs from in vitro fertilization. Whereas on culturing eggs from in vivo fertilization, LIF is more beneficial with dose dependent in high concentration.
Kim, D. J.;H. J. Chung;S. J. Uhm;Lee, H. T.;K. S. Chung
Proceedings of the KSAR Conference
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한국동물번식학회 2001년도 춘계학술발표대회
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pp.30-30
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2001
The culture of preantral follicles has important biotechnological implications through its potential to produce the large quantity of oocytes for embryo production, transgenesis research, conservation of rare breed, and a potential source of ovarian genetic material. The present study was conducted to establish the optimal conditions of in vitro culture for intact bovine preantral follicles; and to examine the developmental ability of oocytes derived from the in vitro-grown preantral follicles; and to investigate the effects of various concentrations of FSH and LH on these processes. Bovine preantral follicles (150 $\pm$ 1.2${\mu}{\textrm}{m}$), surrounded by theca cell, were isolated enzymetically and mechanically from ovarian cortical slides in Leibovitz L-15 medium containing 1 mg/$m\ell$ collagens and 0.2 mg/$m\ell$ DNase I and cultured for 25 days in the presence of different concentrations of bovine FSH and LH in $\alpha$MEM medium with insulin, transferrin, and selenite. The survival was tested by frypan Blue and Hematoxylin. The survival and growth rates of follicles were higher in FSH treatment groups than these in control (P<0.001), but there were no significant differences between the LH treatment groups and the control. In 25 days, the survival and growth rates of follicles in FSH and LH treatment group (50%, 300$\pm$1.0${\mu}{\textrm}{m}$) were higher than in FSH treatment group (40%, 244$\pm$0.5${\mu}{\textrm}{m}$) and the control group (25%, 160$\pm$ 1.0${\mu}{\textrm}{m}$). Fifty-five percent of healthy antral follicles were obtained, and 60% of the oocytes complete meiotic maturation to the metaphase II stage. Twenty-two percent of the mature oocytes underwent cleavage, and 9% developed to the blastocyst stage. In this study, in vitro-grown oocytes (111 $\pm$$1.5mutextrm{m}$), under our culture conditions, were not equivalent in size to the in vivo-grown oocytes (130$\pm$1.3${\mu}{\textrm}{m}$). Therefore, these results suggest that bovine preantral follicles with intact theca cell can grow to the antral stage in 25days, and that oocytes from those follicles can acquire the meiotic competence and normally undergo fertilization and development to the blastocyst stage. However, the developmental capacity of in vitro-grown oocytes is presumably not comparable to those of the in vivo counterparts.
Dental implants have been developed for enhancement of osseointegration. Biocompatibility, bone affinity and surface characteristics of dental implants are very important factors for osseointegration. The aim of the present study was to determine the cytotoxicity and the bone affinity of titanium phosphide(Ti-P) implant material. The Ti-P surface was obtained by vacuum sintering of titanium within compacted hydroxyapatite powder. The composition and the chemical change of the surface were determined by Auger electron spectroscopy. The in vitro cytotoxicity was evaluated by the viability of the bone cells and macrophages obtained from chicken embryo and rat,s peritonium, respectively. For the comparative evaluation, 316L stainless steel, commercially pure titanium and Ti-P materials, prepared in size of 1O.0mm in diameter and 5.0mm in height, were immersed separately in bone cells and macrophages for 10 days. For the evaluation of the in vivo bone affinity, 316L stainless steel, commercially pure titanium and Ti-P materials, prepared in size of 5.0mm in diameter and 10.0mm in length, were implanted after drilling in diameter 5.5mm in femurs of 2 dogs weighing 10Kg more or less. Six weeks after implantation the specimens were prepared for histopathological examination and were observed under light microscope. In comparison of in vitro bone cell viability, Ti-P and commercially pure titanium groups were not significantly different from control group (p>O.1), but 316L stainless steel group was significantly lower than control group(p<0.05). There was no statistical difference in the viability of macrophages between 3 different groups and control group(p>O.l). In comparison of in vivo study, 316L stainless steel and commercially pure titanium showed fibrous encapsulation, but Ti-P showed remarkable new bone formation without any fibrous tissue. The results demonstrate that Ti-P has favorable biocompatibility and bone affinity, and suggest that dental implants with Ti-P surface may enhance osseointegration.
The purpose of the present study was to set up basic information of size and status of ovaries by using ultrasonography to retrieve in vivo matured oocytes with ovum pick- up method. Ovaries were collected from the abattoir in Jeju in May and June which is breeding season. When the size of ovaries on ultrasonography was compared with real size measured by caliper, no significant difference was shown (p<0.05). The number of preovulatory follicles (>21mm) was investigated with ultrasonography and naked eyes. Ultrasonography group had 0.83 preovulatory follicles per ovary and naked-eye group had 0.75 preovulatory follicle per ovary and their average size was 2.86 cm and 2.34 cm, respectively. The average number of follicle was 4.25 with ultrasonography and 4.38 with naked eyes. There was no significant difference considering the size of follicle and number of follicle between ultrasonography and actual size except for the size of preovulatory follicle, suggesting that information of ultrasonography is able to use for OPU or other reproductive technology of mare.
Ock, Sun A;Oh, Keon Bong;Hwang, Seongsoo;Kim, Youngim;Kwon, Dae-Jin;Im, Gi-Sun
Journal of Embryo Transfer
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제30권3호
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pp.249-255
/
2015
Diabetes mellitus, the most common metabolic disorder, is divided into two types: type 1 and type 2. The essential treatment of type 1 diabetes, caused by immune-mediated destruction of ${\beta}-cells$, is transplantation of the pancreas; however, this treatment is limited by issues such as the lack of donors for islet transplantation and immune rejection. As an alternative approach, stem cell therapy has been used as a new tool. The present study revealed that bone marrowderived mesenchymal stromal cells (BM-MSCs) could be transdifferentiated into pancreatic cells by the insertion of a key gene for embryonic development of the pancreas, the pancreatic and duodenal homeobox factor 1 (PDX1). To avoid immune rejection associated with xenotransplantation and to develop a new cell-based treatment, BM-MSCs from ${\alpha}$-1,3-galactosyltransferase knockout (GalT KO) pigs were used as the source of the cells. Transfection of the EGFP-hPDX1 gene into GalT KO pig-derived BM-MSCs was performed by electroporation. Cells were evaluated for hPDX1 expression by immunofluorescence and RT-PCR. Transdifferentiation into pancreatic cells was confirmed by morphological transformation, immunofluorescence, and endogenous pPDX1 gene expression. At 3~4 weeks after transduction, cell morphology changed from spindle-like shape to round shape, similar to that observed in cuboidal epithelium expressing EGFP. Results of RT-PCR confirmed the expression of both exogenous hPDX1 and endogenous pPDX1. Therefore, GalT KO pig-derived BM-MSCs transdifferentiated into pancreatic cells by transfection of hPDX1. The present results are indicative of the therapeutic potential of PDX1-expressing GalT KO pig-derived BM-MSCs in ${\beta}-cell$ replacement. This potential needs to be explored further by using in vivo studies to confirm these findings.
In the present study, we investigated the effect of maturity and motility of spermatozoa on the formation of pronuc-leus and subsequent developmental capacity of the human embryo in vitro. The fertilization was performed by means of intracytoplasmic sperm injection (ICSI) in HEPES-buffered m-TCM-199 medium. In the first part of the experiment, motile or im-motile human spermatozoa ejaculated were injected into cumulus-enclosed human oocytes matured in vivo. Significantly (p<0.002) higher proportion of oocytes that was injected with motile spermatozoa formed 2 pronuclei than the oocytes injected with immotile spermatozoa (79.8% vs 51.7%). In the second part of the experiment, cumulus-enclosed human oocytes matured in vivo were injected with motile or immotile spermatozoa collected from testes. There was no difference between motile and immotile spermatozoa. In the third part of the experiment, using modified Tyrode's medium containing 10.0 mM lactate, 0.5 mM pyruvate, 0.2 mM taurine, 1.0 mM glutamine, 2.22 mM MEM amino acids, vitamin and 10% human follicular fluid, we found that the development of oocytes that formed 2 pronuclei were able to develop to 9-16 cells regardless of maturity and motility of spermatozoa.
Culture medium (ASF-301) of tHUE-2 cell, human endothelial cell line, and culture medium of these cells (conditioned medium : CM) which affect embryonic development of in vivo fertilized 1-cell embryos of mouse were examined. Two-cell stage block of mouse embryos was overicomed in ASF-301 and CM without EDTA, which usually added in basic medium (modified Whitten Medium: MWM, control) to overcome the 2-cell stage block. The developmental rates of embryos to the blastocyst stage were significantly increased in MWM containing 12.5% of growth factors added to ASF-301 (10mg/ $\ell$ transferrin, 1mg/$\ell$ insulin, 0.01mg/$\ell$ EGF) than those of 100% addition and control, 78.0% vs 20.8 and 52.3%, respectively (P<0.05), but the growth factors was not affected the hatching rate of blastocyst. Using ASF-301 or CM which was not treated, embryonic development into the blastocyst and hatched blastocyst stages were not affected. However, proportions of embryonic development into the blastocyst and hatched blastocyst stages were significantly higher in dilution (ASF-301 1:10; CM 1:3~1:6) than those in control (P,0.05). In ASF-301 dialyzed M.W.<10000 dialysis membrane, the developmental rate upto the hatched blastocyst stage was significantly increased, compared to ASF-301 which was not dialyzed (P<0.05), and hatching rate of blastocyst of these group was singnificantly increased than those in MWM (P<0.05). Compared to CM which was not dialyzed, however, in dialyzed CM was significantly decreased, compared to untreated CM (P<0.05), especially any hatched blastocyst was not appeared. As a result of these experiments indicated that a kind or porper treatment such as a dilution of complex synthetic cell culture medium and conditioned medium, and that a optimal concentration of growth factors are usuful for embryo cultrue in vitro.
Vascular endothelial growth factor (VEGF)-A, a major regulator for angiogenesis, binds and activates two tyrosine kinase receptors, VEGFR1 (Flt-1) and VEGFR2 (KDR/Flk-1). These receptors regulate physiological as well as pathological angiogenesis. VEGFR2 has strong tyrosine kinase activity, and transduces the major signals for angiogenesis. However, unlike other representative tyrosine kinase receptors which use the Ras pathway, VEGFR2 mostly uses the Phospholipase-$C{\gamma}$-Protein kinase-C pathway to activate MAP-kinase and DNA synthesis. VEGFR2 is a direct signal transducer for pathological angiogenesis including cancer and diabetic retinopathy, thus, VEGFR2 itself and the signaling appear to be critical targets for the suppression of these diseases. VEGFR1 plays dual role, a negative role in angiogenesis in the embryo most likely by trapping VEGF-A, and a positive role in adulthood in a tyrosine kinase-dependent manner. VEGFR1 is expressed not only in endothelial cells but also in macrophage-lineage cells, and promotes tumor growth, metastasis, and inflammation. Furthermore, a soluble form of VEGFR1 was found to be present at abnormally high levels in the serum of preeclampsia patients, and induces proteinurea and renal dysfunction. Therefore, VEGFR1 is also an important target in the treatment of human diseases. Recently, the VEGFR2-specific ligand VEGF-E (Orf-VEGF) was extensively characterized. Interestingly, the activation of VEGFR2 via VEGF-E in vivo results in a strong angiogenic response in mice with minor side effects such as inflammation compared with VEGF-A, suggesting VEGF-E to be a novel material for pro-angiogenic therapy.
Park, Mi-Young;Lee, Yong-Hwan;Bae, Hae-Rahn;Lee, Ryang-Hwa;Lee, Sang-Ho;Jung, Jin-Sup
The Korean Journal of Physiology and Pharmacology
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제3권2호
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pp.157-164
/
1999
To determine molecular mechanisms of Aquaporin-CD (AQP2) gene regulation, the promoter region of the AQP2 gene was examined by transiently transfecting a promoter-luciferase reporter fusion gene into mouse renal collecting duct cell lines such as mIMCD-3, mIMCD-K2, and M-1 cells, and NIH3T3 mouse embryo fibroblast cells. PCR-Southern analysis reveals that mIMCD-3 and mIMCD-K2 cells express AQP2, but M-1 and NIH3T3 cells do not, and that the treatment with cpt-cAMP $(400\;{\mu}M)$) or forskolin/isobutylmethylxanthine (IBMX) increased the AQP2 expression in IMCD cells. In both IMCD and NIH3T3 cells, the constructs containing the promoter of AQP2 gene showed promoter activities, indicating lack of tissue-specific element in the 1.4 kb 5'-flanking region of the mouse AQP2 gene. Luciferase activity in the IMCD cells transfected with the construct containing 5-flanking region showed responsiveness to cpt-cAMP, indicating that the 1.4 kb 5'-flanking region contains the element necessary for the regulatory mechanism by cAMP. The promoter-luciferase constructs which do not have a cAMP-responsible element (CRE) still showed the cAMP responsiveness in IMCD cells, but not in NIH3T3 cells. Increase in medium osmolarity did not affect AQP2 promoter activity in mIMCD-K2 cells. These results demonstrate that AQP2 gene transcription is increased with cAMP treatment through multiple motifs including CRE in the 5'-flanking region of the gene in vitro, and the regulatory mechanism may be important for in vivo regulation of AQP2 expression.
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