• Toxicological Research
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• v.26 no.1
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• pp.67-74
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• 2010

The present study was conducted to obtain information on the effects of amitraz on reproductive and developmental parameters in rats. The test chemical was administered via the drinking water containing 0, 40, 120, and 360 ppm to male rats from 2 weeks before mating to the end of 14-day mating period and to females from 2 weeks before mating, throughout mating, gestation and up to lactational day 4. During the study period, clinical signs, body weights, food intake, organ weights, reproductive and littering findings, necropsy findings, sperm parameters, and histopathology were examined. At 360 ppm, decreases in the body weight gain, food consumption, and the number of live pups and an increase in the post-implantation loss were observed. In addition, decreases in the seminal vesicle weight and sperm motility were found in males. At 120 ppm, a decrease in the food consumption was found transiently in both males and females, but no reproductive and developmental toxicity was observed in both sexes. There were no signs of either general or reproductive and developmental toxicity in the 40 ppm group. Based on these results, it was concluded that the repeated oral administration of amitraz to rats resulted in a decrease in the food consumption at 120 ppm and decreases in the seminal vesicle weight, sperm motility, and the number of live pups and an increase in the post-implantation loss at 360 ppm in rats. Under these experimental conditions, the no-observed-adverse-effect level (NOAEL) of amitraz for general and reproduction/developmental toxicity was believed to be 120 ppm, and the no-observed-effect level (NOEL) of amitraz was believed to be 40 ppm in rats.

• Development and Reproduction
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• v.18 no.3
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• pp.145-152
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• 2014

This study was performed to investigate the effect of of transdermal testosterone gel (TTG) on controlled ovarian stimulation (COS) and IVF outcomes and ovarian morphology according to pretreatment duration in poor responders. A total of 120 women were recruited for this pilot study. They were randomized into control, 2 weeks, 3 weeks or 4 weeks TTG treatment groups. For three TTG treatment groups, 12.5 mg TTG was applied daily for 2 weeks, 3 weeks or 4 weeks in preceding period of study stimulation cycle. After 3 weeks of TTG pretreatment, significant increase of antral follicle count (AFC) and significant decreases of mean follicular diameter (MFD) and resistance index (RI) value of ovarian stromal artery were observed (p=0.026, p<0.001, p<0.01, respectively). The total dose of rhFSH administered for COS significantly decreased after 3 and 4 weeks TTG treatment both compared with control group (p<0.001, p<0.001). The numbers of oocytes retrieved and mature oocytes were significanty higher in 3 and 4 weeks TTG treatment groups than control group (p<0.001, p<0.001 in the number of oocytes retrieved; p<0.001, p<0.001 in the number of mature oocytes). The clinical pregnancy rate and live birth rate were increased only in 4 weeks TTG treatment group compared with control group (p=0.030 and p=0.042, respectively). These data demonstrated that TTG pretreatment for 3 to 4 weeks increases AFC and ovarian stromal blood flow, thereby potentially improving the ovarian response to COS and IVF outcome in poor responders undergoing IVF/ICSI.

• Development and Reproduction
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• v.21 no.2
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• pp.193-204
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• 2017

The influence of triploidization on histological characteristics of retina, trunk kidney, liver and midgut tissue, and cell cycle of tail fin and gill tissue in far eastern catfish, Silurus asotus were analyzed. In the infertile triploid fish, the nucleus and/or cell size of secondary proximal tubule cells of trunk kidney, hepatocyte and midgut epithelium are much larger than those of the corresponding cells in the diploid fish (P<0.05). However, triploid tissue showed fewer number of outer nuclear layer in retina and nuclei in secondary proximal tubule of trunk kidney than those for diploid tissue. The mean percentages of the $G_l-$, the S- and the $G_2+M-phase$ fractions were 92.5%, 3.2% and 4.3% in tail fin tissue of diploid, and 93.4%, 2.6% and 4.0% in those of triploid, respectively. There were no significant differences in the percentages of each cell cycle fraction between diploid and triploid. The mean percentages of each phase fractions were 75.1%, 11.1% and 13.8% in gill tissue of diploid and 85.2%, 8.9% and 5.9% in those of triploid, respectively. The differences of cell cycle between tail fin tissue and gill tissue were statistically significant in diploid and triploid (P<0.05). Also, the differences between diploid and triploid were statistically significant in tail fin tissue and gill tissue (P<0.05). Cyclin D1 and cyclin E expressions were not significantly difference between gill tissue and tail fin tissue, and protein expressions of induced triploid were higher than those of diploid. Results from this study suggest that some characteristics in the triploid exhibiting larger cell and nucleus size with fewer number of cell than diploid can be used as an indicator in the identification of triploidization and ploidy level in far eastern catfish.

• Research in Plant Disease
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• v.26 no.2
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• pp.116-119
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• 2020

To investigate the effects of Brassicaceae cover crops on clover cyst nematode, Heterodera trifolii, 10 cultivars consisting of six of oil radish and four of white mustard were planted in the nematode infected field at Jeongseon city. Two months after planting, the cover crops were plow down and incorporated into the soil using rotavator, decomposed for 1 month, then transplanted kimchi-cabbages. After 70 days, the density of eggs inside of the cyst and the number of females in the soil were examined. As a result, the reproduction rates of eggs in each plots of Adios and Anaconda cultivars, which were 0.04 and 0.02, respectively, were greatly reduced. The number of females in the plots of above two cultivars showed means at 2.5 and 3.5 per 300 ㎤ soil, which were lower than those of other plots. In addition, fresh weights of three plants in the two plots, which were 7.67 and 7.35 kg, were significantly higher than that of the control plot. Collectively, these results suggest that the two cultivars of Brassicaceae cover crops, Adios and Anaconda, could be used for reducing the cyst nematode density.

• Preventive Nutrition and Food Science
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• v.19 no.3
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• pp.136-144
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• 2014

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. This study was conducted to evaluate the effects of Platycarya strobilacea S. et Z. (PSE) extract on mouse hair growth and to determine the mechanism of action of PSE. PSE was purchased and its antioxidant activities, such as electron donating ability, total polyphenol content, and flavonoid content were tested. Toxicity during topical treatment was determined by the CCK-8 assay, a cell viability test. Fifteen 4-week-old male C57BL/6 mice were assigned to receive one of three treatments: dimethyl sulfoxide (negative control), minoxidil (positive control) or PSE. Test materials were topically applied to the shaved dorsal skin of each mouse daily for 3 weeks. After 21 days, we observed skin tissue hair follicle morphology and length, mast cell number, and stem cell factor (SCF) expression using hematoxylin and eosin (H&E), toluidine blue, and immunohistochemical staining, respectively. Furthermore, the expression of cytokines involved in hair growth [i.e., insulin-like growth factor (IGF)-1, keratinocyte growth factor (KGF), and transforming growth factor (TGF)-${\beta}1$] was determined by PCR. PSE was found to have very high antioxidant activity. The cell viability rate of PSE-treated mice was markedly higher than that of mice in the control group. We also observed an increase in hair follicle length, strong SCF staining, and a decrease in mast cell number in the PSE group. In addition, PSE-treated mice had higher IGF-1 and KGF expression and lower TGF-${\beta}1$ expression than mice in the minoxidil-treated group. These results suggest that topical application of PSE promotes hair growth by intensifying SCF, suppressing mast cell production, and increasing hair growth-promoting cytokine expression.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.10
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• pp.1581-1590
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• 2018

Objective: The aim of this study was to clone alternative splicing isoforms of pig myoneurin (MYNN), predict the structure and function of coding protein, and study temporal and spatial expression characteristics of each transcript. Methods: Alternative splice isoforms of MYNN were identified using RNA sequencing (RNA-seq) and cloning techniques. Quantitative real-time polymerase chain reaction (qPCR) was employed to detect expression patterns in 11 tissues of Large White (LW) and Mashen (MS) pigs, and to study developmental expression patterns in cerebellum (CE), stomach (ST), and longissimus dorsi (LD). Results: The results showed that MYNN had two alternatively spliced isoforms, MYNN-1 (GenBank accession number: KY470829) and MYNN-2 (GenBank accession number: KY670835). MYNN-1 coding sequence (CDS) is composed of 1,830 bp encoding 609 AA, whereas MYNN-2 CDS is composed of 1,746 bp encoding 581 AA. MYNN-2 was 84 bp less than MYNN-1 and lacked the sixth exon. MYNN-2 was found to have one $C_2H_2$ type zinc finger protein domain less than MYNN-1. Two variants were ubiquitously expressed in all pig tissues, and there were significant differences in expression of different tissues (p<0.05; p<0.01). The expression of MYNN-1 was significantly higher than that of MYNN-2 in almost tissues (p<0.05; p<0.01), which testified that MYNN-1 is the main variant. The expression of two isoforms decreased gradually with increase of age in ST and CE of MS pig, whereas increased gradually in LW pig. In LD, the expression of two isoforms increased first and then decreased with increase of age in MS pig, and decreased gradually in LW pig. Conclusion: Two transcripts of pig MYNN were successfully cloned and MYNN-1 was main variant. MYNN was highly expressed in ST, CE, and LD, and their expression was regular. We speculated that MYNN plays important roles in digestion/absorption and skeletal muscle growth, whereas the specific mechanisms require further elucidation.

• Development and Reproduction
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• v.13 no.4
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• pp.227-237
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• 2009

Recently, adipose mesenchymal stem cells (AdMSC) that are similar to bone marrow MSC and blood derived MSC are thought to be another source for stem cell therapy. However, the diseases that can be applied for stem cells therapy are age-dependent degenerative diseases. Accordingly, the present study investigated the growth and differentiation potential to neural cells of human AdMSC (hAdMSC) obtained from aged thirty, forty and fifty. The growth of cells and cell viability were measured by passage and neural differentiation of hAdMSC was induced in neural differentiation condition for 10 days. Our results demonstrated that cell number, viability and morphology were not different from hAdMSC by age and passage. Immunofluorescence analysis of neural cell marker (TuJ1, NSE, Sox2, GFAP or MAP2) demonstrated no significant differences in neural cell differentiation by age and passage. As the number of passage was increased, the mRNA level of MAP2 and Sox2 was decreased in hAdMSC from age of 50 compared to hAdMSC from age of 30. In conclusion, the present study demonstrated that ability of neural cell differentiation of hAdMSC was maintained with ages, suggesting that autologous stem cells from aged people can be applied for stem cell therapy with age-dependent neural disease with the same stem cell quality and ability as stem cell derived from young age.

• Korean Journal of Ichthyology
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• v.6 no.2
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• pp.222-236
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• 1994

Sexual maturation and spawning of the spottybelly greenling, Hexagrammos agrammus were histologically studied under photomicroscopy by considering changes in gonadosomatic index, hepatosomatic index and fatness, egg diameter composition, first sexual maturity and fecundity. The fish samples were collected monthly at the coastal area of Tongbaeksom, Pusan, Korea from July 1991 to July 1992. The gonadosomatic index(GSI) increased in September and reached the maximum value(female 4.31, male 1.61) in November when the gonad was mature and ripe. The values were decreased suddenly during the spawning season from December, and declined from January to August. The annual variations of hepatosomatic index(HSI) appeared to be correlated with those of GSI in female but were not significantly correlated in male. HSI in female began to increase in autumn with the increase of GSI, and reached the maximum in winter when the ovary was mature. Percentages of first sexual maturity in female and male fish were 50 % in 11.0~11.9 cm and 100 % in 13.0~13.9 cm groups. Both sexes participated in reproduction from one year old. H. agrammus was considered as a polycyclic species and spawns 3 times or more in the spawning season. Number of total and mature eggs in the absolute fecundity were proportional to standard length and body weight, respectively. Number of total and mature eggs in relative fecundity were also proportional to standard length, but rather decrease with increasing of body weight. Fatness coefficients reached the maximum value(female 15.32, male 15.14) in September(growing stage), and the values were sharply decreased after spawning. Thereafter, fatness values were gradually increased, therefore, the monthly changes in fatness coefficient closely correlated with the reproductive cycle. Sex ratios of female and male sexes of this species are showed 54.18 %, 45.82 %, respectively.

• Journal of Embryo Transfer
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• v.32 no.3
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• pp.171-176
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• 2017

This study was conducted to investigate the breeding status of farms to improve the production efficiency of Hanwoo calf. The study was conducted on 45 farms divided into two groups. This study was conducted to investigate the breeding size and breeding area of Hanwoo cows. The average age at first delivery of Hanwoo was 28.7 months. The number of artificial insemination per pregnancy was $1.45{\pm}0.32$, and the number of artificial insemination days after birth was 119.8 days. Conception rates were $75.2{\pm}16.93%$ for small farms and $70.6{\pm}17.46%$ for medium sized farms and $71.4{\pm}11.03%$ for large farms. When we looked at farming methods, 'the farmers using estrus observation aids' had 10.42% higher calf production rate than the 'unused farmers'. The farms vaccinated with IBR and BVDV for breeding cattle showed a 4.41% decrease in abortion, stillbirth and mortality. According to farming conditions, conception rate and delivery rate improved by 3.47% and 18.29%, respectively, when grazing and exercising were performed. Observation, immunization and grazing were found to be important indicators for improving calf production efficiency in Hanwoo farm. This study can be used as a research data to improve the reproductive rate of farmhouse sites through the survey on the breeding status of Hanwoo farmers.

• Development and Reproduction
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• v.10 no.3
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• pp.169-175
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• 2006

Ginseng is the best known and most popular herbal medicine used worldwide. In spite of reported beneficial effects of ginseng on the CNS, there is few scientific evidences established at the cellular level. Among more than 30 ginsenosides, Rb1 and Rg1, the active ingredients of ginseng, are regarded as the main compounds responsible for many pharmaceutical actions of ginseng. Daily treatment with Rb1 or Rg1 for 3 d significantly decreased the number of bromodeoxyuridine(BrdU)(+) cells in primary neural progenitor cells(NPCs) isolated from hippocampi at embryonic day 16.5(E16.5). In contrast, treatment with Rb1 or Rg1 greatly increased the number of microtubule associated protein(MAP2) (+) cells. In addition, the transcription factors, Ngn1 and Hes1, proneural members of the basic helix-loop-helix(bHLH) family, significantly increased in Rb1 or Rg1 treated-NPCs. Based on these results, we suggest for the first time that ginsenosides Rb1 and Rg1 decrease proliferation but promote neuronal differentiation of hippocampal NPCs.