• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.5
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• pp.419-426
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• 2006

This study investigated the ecology and growth of Monostroma nitidum Wittrock in both its natural habitat and the laboratory. The maximum length, width, and weight of M. nitidum in March were 9.0$\pm$4.7 cm, 9.6$\pm$3.6 cm, and 1.52$\pm$1.13 g, respectively. Yellowish-green or yellowish-brown reproductive thalli began to appear in January, and over 80% of the thalli matured by March. The male and female spores were ca. 6 $\mu$m long, and elongate and ovoid in shape. The spores had two flagella and one-eye spot, and tended to swim toward light. Maximum number of spores released from matured thalli was 236 cells/mL after 70 minutes at a light intensity of 100 $\mu$mol/m$^2$/s. The zygote diameter ranged from 3.4-6.0 $\mu$m (mean 4.2 $$m) and increased to 69.8 $\mu$m 14 weeks after culture. The mass release of zoospores was observed from thalli in the dark (3 to 12 days), after 30 min under dry conditions in the shade, at 25$^{\circ}C$, and a light intensity of 100 $\mu$mol/m$^2$/s. The maximum number of zoospores released was 109.8 cells/mL after 60 min of induction. M. nitidum fronds on the net increased to 6.8-7.2 cm in length, and 6.6-8.9 cm in width during the winter.

• KSBB Journal
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• v.17 no.4
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• pp.409-415
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• 2002

A certain group of phytochemicals such as isoflavone have been proven to act as a phytoestrogen. After thorough the study of different bibliographic herbs excluding soybeans, dates, pomegranates, and other publicized plants, three different edible herbs by Korean Food Regulation were extracted for the animal study on the effect of estrogen replacement. The herbal extract(FGF271) has been orally administered into 51 weeks old partial ovariectomized rats for 5 weeks with the different dosages of 100 and 1,000 mg/kg, respectively. It was observed that 1) serum estrogen level was increased in both 100 and 1,000 mg/kg group, 2) the distension of uterus was made dose dependently and significantly different in 1,000 mg/kg group (p.0.05) from control in the gross findings, 3) the weight of uterus was increased in 1,000 mg/kg group, and 4) the action on reproductive tissues was clear in the microscopic findings in terms of hyperplasia of endometrial epithelial cell, cystic change of submucosa, dilatation of uterus (significantly increased in 1,000 kg/mg), and follicular cystic changes in ovary. As a result, FGF271 seemed to act as a phytoestrogen by inducing the change in ovary and uterus and by increasing the serum estrogen concentration.

• Archives of Pharmacal Research
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• v.24 no.4
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• pp.360-366
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• 2001

Gangliosides are ubiquitous membrane components in mammalian cells and are suggested to play important roles in various functions such as cell-cell interaction, adhesion, cell differentiation, growth control and signaling. Among all ganglio-series gangliosides, GM3 has the simplest carbohydrate structure, and has been shown as a major gangliosides, in male reproductive system. To study GM3 distribution in the seminiferous tubule and epididymis, frozen sections were stained with specific monoclonal antibody (MAb) against ganglioside GM3. In the seminiferous tubule of testis, pachytene spermatocytes and spermmatids expressed ganglioside GM3, but not in spermatogonia and sertoli cells. Spermatogonia and sertoli cells near the basement membrane were negatively reacted to anti-GM3. In the epididymis, GM3 was expressed only in some interstitial cells. Taken togethers, these results suggest that the expression of ganglioside GM3 in rat seminiferous tubule and epididymis is spatio-temporally regu lated during spermatogenesis.

• Reproductive and Developmental Biology
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• v.30 no.3
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• pp.189-194
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• 2006

Sperm-mediated gene transfer(SMGT) can be used to transfer exogenous DNA into the oocyte at fertilization. The main objective of this study was to assess efficiency of transferring mitochondrial DNA(mtDNA) fragment into boar spermatozoa in either presence or absence of liposome and quality of transfected spermatozoa. The mtDNA of chicken liver was isolated and purified by phenol and alkaline lysis extraction, and it was inserted to plasmid. The genome of transfected spermatozoa treated with DNase I was purified by alkaline lysis, and then amplified by the PCR analysis. After electrophoresis, DNA quantitation of each well was calculated by comparison of the band intensity with standard. As a result, exogenous DNA was composed of mtDNA fragment(1.2 kb) and plasmid(2.7 kb). On the other hand, efficiency of transfection by liposome($9.0{\pm}0.34ng/{\mu}l$) in SMGT was higher than that by DNA solution($6.9{\pm}0.53ng/{\mu}l$). However, there was no significant difference. Transfering exogenous DNA into spermatozoa was completed within 90 min of incubation. In another experiment, there were significant (p<0.05) differences between transfected spermatozoa using both DNA solution and DNA/liposome completes with unheated spermatozoa for viability ($70.8{\pm}1.80$ and $68.0{\pm}2.16%$ vs. $83.3{\pm}1.69%$, respectively) and motility($78.7{\pm}1.59$ and $79.3{\pm}2.14%$ vs. $86.7{\pm}1.59%$, respectively). This study indicates that exogenous mtDNA can be efficiently transferred into boar spermatozoa regardless of the presence of liposome, and transfected spermatozoa can also use insemination and in vitro fertilization to generate transgenic pig.

• Genes and Genomics
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• v.40 no.12
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• pp.1259-1267
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• 2018

Litchi (Litchi chinensis Sonn.) is an important subtropical fruit crop with high commercial value due to its high nutritional values and favorable tastes. However, irregular bearing attributed to unstable flowering is a major ongoing problem for litchi producers. Previous studies indicate that low-temperature is a key factor in litchi floral induction. In order to reveal the genetic and molecular mechanisms underlying the reproductive process in litchi, we had analyzed the transcriptome of buds before and after low-temperature induction using RNA-seq technology. A key flower bud differentiation associated gene, a homologue of FLORICAULA/LEAFY, was identified and named LcLFY (GenBank Accession No. KF008435). The cDNA sequence of LcLFY encodes a putative protein of 388 amino acids. To gain insight into the role of LcLFY, the temporal expression level of this gene was measured by real-time RT-PCR. LcLFY was highly expressed in flower buds and its expression correlated with the floral developmental stage. Heterologous expression of LcLFY in transgenic tobacco plants induced precocious flowering. Meantime, we investigated the sub-cellular localization of LcLFY. The LcLFY-Green fluorescent protein (GFP) fusion protein was found in the nucleus. The results suggest that LcLFY plays a pivotal role as a transcription factor in controlling the transition to flowering and in the development of floral organs in litchi.

• Horticulture, Environment, and Biotechnology : HEB
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• v.59 no.6
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• pp.815-826
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• 2018

The intense drought affecting olive production in Northern Chile underscores the need to research non-traditional irrigation strategies to obtain the best crop performance. Accordingly, this study aimed to obtain preliminary data to guide future research on this topic. Different water replenishment levels on crop evapotranspiration ($ET_c$ ; 13.5, 27.0, 40.5, and 54%) were established in a young orchard, cv. Arbequina, from the end of fruit drop (EFD) to full bloom in the next season. We evaluated the influence of plant water status (${\Psi}_{stem}$ ) and crop load, considered as function of fruit number divided by trunk cross-sectional area, on reproductive and productive variables using multiple linear regressions. Our results show that crop load and ${\Psi}_{stem}$ measured from EFD to harvest affected yield components. Nevertheless, ${\Psi}_{stem}$ had the strongest influence on fruit size, pulp development, oil accumulation, and yield. Oil content and yield were reduced by 54% and 50% for each MPa, respectively, from ${\Psi}_{stem\;EFD-H}$ -1.8 MPa, an effect that intensified as crop load increased. During the period of flower development (September-November), the number of flowers per inflorescence and percentage of perfect flowers were reduced when ${\Psi}_{stem}$ was less than -2.0 MPa. These preliminary results showed that bud differentiation, inflorescence and flower formation are highly sensitive to water deficit.

• Journal of Animal Science and Technology
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• v.65 no.4
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• pp.759-766
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• 2023

Visual estrus observation can only be confirmed at a rate of 50%-60%, which is lower than that obtained using a biosensor. Thus, the use of biosensors provides more opportunities for artificial insemination because it is easier to confirm estrus than by visual observation. This study determines the accuracy of estrus prediction using a ruminoreticular biosensor by analyzing ruminoreticular temperature during the estrus cycle and measuring changes in body activity. One hundred and twenty-five Hanwoo cows (64 with a ruminal biosensor in the test group and 61 without biosensors in the control group) were studied. Ruminoreticular temperatures and body activities were measured every 10 min. The first service of artificial insemination used gonadotropin-releasing hormone (GnRH)-based fixed-time artificial insemination protocol in the control and test groups. The test group received artificial insemination based on the estrus prediction made by the biosensor, and the control group received artificial insemination according to visual estrus observation. Before artificial insemination, the ruminoreticular temperature was maintained at an average of 38.95 ± 0.05℃ for 13 h (-21 to -9 h), 0.73℃ higher than the average temperature observed at -48 h (38.22 ± 0.06℃). The body activity, measured using an indwelling 3-axis accelerometer, averaged 1502.57 ± 27.35 for approximately 21 h from -4 to -24 h before artificial insemination, showing 203 indexes higher body activity than -48 hours (1299 ± 9.72). Therefore, using an information and communication techonology (ICT)-based biosensor is highly effective because it can reduce the reproductive cost of a farm by accurately detecting estrus and increasing the rate of estrus confirmation in cattle.

• Journal of Veterinary Clinics
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• v.31 no.5
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• pp.394-402
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• 2014

The objective of this study was to investigate the effect of chronic unpredictable stress on the reproductive function and ovarian luteinizing hormone receptor (LHR) expression. 9-week-old C57BL/6 female mice were randomly divided into two groups: control group and stressed group. Mice have been stressed twice a day for 35 days with 12 different stressors which were randomly selected. The results demonstrate that there is significant increase in the anxiety-related behaviors (P < 0.05), decrease body weight gain rate (P < 0.01) and decrease in the average of litter size in stressed mice compared with control group (P < 0.01). Furthermore, the rate of primary, secondary and early antral follicles in stressed mice significantly decreased (P < 0.05), whereas that of atretic follicles significantly increased compared with control mice (P < 0.01). The immunohistochemical analysis revealed that reduced LHR expression in granulosa cells of follicle and luteal cells of corpus luteum in response to chronic unpredictable stress. The western blot analysis revealed significantly decrease in LHR expression in the stressed mice ovaries compared with the control (P < 0.05). These results suggest that ovarian LHR expression affected by chronic unpredictable stress and the modulated ovarian LHR is responsible for ovarian follicular maldevelopment and reproductive dysfunction.

• Journal of Science and Technology Studies
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• v.5 no.1 s.9
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• pp.93-123
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• 2005

This work has following two research goals. First, IVF treatments that have been recently going on in Korea are reexamined from the perspective of women's reproductive rights. Second, the intimate connection between IVF and therapeutic cloning research, in that remnant embryos and eggs that have been secured through IVF treatments have served as a main source of supply for therapeutic cloning research, has been emphasized. The fact that the influencing power of tradition on Korean families and women and IVF techniques eventually joined their hands in support of therapeutic cloning research is noted. Analysis of experiences of infertility by women in the realms of family, medical care during IVF treatment, and therapeutic cloning research that requires continuous supply of eggs leads to following conclusions. First, in the realm of family, infertile women were not only relegated to the status of abnormality but pressured to question their own womanhood. Under this circumstance, IVF treatment helped to reinforce the traditional concept of biological motherhood, thus categorizing married women giving birth to babies and married women who can't or refuses to do so to 'normal ones' and 'abnormal ones' respectively. Second, in the realm of medical care an infertile woman could rediscover her own body during the process of IVF treatment. By going through the processes of hormone treatment, implantation, conception, miscarriage, and so on, she could realize that her own body is understood in diverse ways to her, her family, and the medical profession. Third, in the realm of the state, IVF treatment that was serving as the main supplier of research materials for therapeutic cloning research has been able to avoid controversy in public discourses since the latter has emerged as a signifier of new national economic workhorse for the 21st century. As therapeutic cloning research went into high gear, the status of women as egg providers began to assume a political dimension. Women as egg providers are called upon to take on a paradoxical role as patriotic contributors to national economy on the one hand and as guardians of sacred 'life' on the other hand. The direction and progress of the research will depend on the ways that women comply, compromise, and/or resist the contradiction brought about by being assigned to assume these two identities: the one as a member of the nation requested to serve as a part of national economic development project, even though considered ineligible for financial recompense, and the other one as a guardian of sacred 'life,' even though she have to serve the research that is allowed to create a 'life' to destroy a 'life.'

• Clinical and Experimental Reproductive Medicine
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• v.33 no.2
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• pp.125-132
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• 2006

Objective: In the previous study, we complied the differentially expressed genes during early folliculogenesis. Objective of the present study was to identify downstream target genes of transcription factors (TFs) using bioinformatics for selecting the target TFs among the gene lists for further functional analysis. Materials & Methods: By using bioinformatics tools, constituent domains were identified from database searches using Gene Ontology, MGI, and Entrez Gene. Downstream target proteins/genes of each TF were identified from database searches using TF database ($TRANSFAC^{(R)}$ 6.0) and eukaryotic promoter database (EPD). Results: DNA binding and trans-activation domains of all TFs listed previously were identified, and the list of downstream target proteins/genes was obtained from searches of TF database and promoter database. Based on the known function of identified downstream genes and the domains, 3 (HNF4, PPARg, and TBX2) out of 26 TFs were selected for further functional analysis. The genes of wee1-like protein kinase and p21WAF1 (cdk inhibitor) were identified as potential downstream target genes of HNF4 and TBX2, respectively. PPARg, through protein-protein interaction with other protein partners, acts as a transcription regulator of genes of EGFR, p21WAF1, cycD1, p53, and VEGF. Among the selected 3 TFs, further study is in progress for HNF4 and TBX2, since wee1-like protein kinase and cdk inhibitor may involved in regulating maturation promoting factor (MPF) activity during early folliculogenesis. Conclusions: Approach used in the present study, in silico analysis of downstream target genes, was useful for analyzing list of TFs obtained from high-throughput cDNA microarray study. To verify its binding and functions of the selected TFs in early folliculogenesis, EMSA and further relevant characterizations are under investigation.