• 한국수정란이식학회지
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• 제14권3호
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• pp.177-184
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• 1999

This study was conducted to find out the effect of follicle size and oocyte type on in vitro maturation of poricine follicular oocytes. TCM-HEPEAS medium was used to basic medium, and the oocyte matured in vitro was stained with the Rapid staining method. The results obtained were summarized as follows; 1. The number of follicles an ovary was 20.5. The number of A-and B-typed oocytes an ovary was 2.34. The proportion of A-and b-types oocytes was 40% of the recovery oocytes. 2. Cumulus expanison indexes(CEI) by the follicle size were 1.62∼2.34(<2mm), 1.27∼2.28(2∼5mm) and 1.46∼2.75(>5mm). It was no differ to maturation rate by the follicle size. 3. The degree of oocyte maturation based on oocyte type did not differ for B-and C-typed oocyted but the index of oocyte type A was higher than that of b-and C-typed oocytes. 4. When follicluar oocytes were cultured for 42 hours, the proportion of the Met-II(second metaphase) stage were 22.5% (degree 1), 35.4%(degree 2) and 65.5% (degree 3).

• Clinical and Experimental Reproductive Medicine
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• 제46권2호
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• pp.43-49
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• 2019

Primordial follicle activation is a process in which individual primordial follicles leave their dormant state and enter a growth phase. While existing hormone stimulation strategies targeted the growing follicles, the remaining dormant primordial follicles were ruled out from clinical use. Recently, in vitro activation (IVA), which is a method for controlling primordial follicle activation, has provided an innovative technology for primary ovarian insufficiency (POI) patients. IVA was developed based on Hippo signaling and phosphatase and tensin homolog (PTEN)/phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT)/forkhead box O3 (FOXO3) signaling modulation. With this method, dormant primordial follicles are activated to enter growth phase and developed into competent oocytes. IVA has been successfully applied in POI patients who only have a few remaining remnant primordial follicles in the ovary, and healthy pregnancies and deliveries have been reported. IVA may also provide a promising option for fertility preservation in cancer patients and prepubertal girls whose fertility preservation choices are limited to tissue cryopreservation. Here, we review the basic mechanisms, translational studies, and current clinical results for IVA. Limitations and further study requirements that could potentially optimize IVA for future use will also be discussed.

• Animal cells and systems
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• 제11권2호
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• pp.191-198
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• 2007

The ultrastructure of germ cells and follicle cells during oogenesis, oocyte degeneration, reproductive cycle, and first sexual maturity in female Cyclina sinensis were investigated for clams collected from Simpo, Jeollabuk-do, Korea, by cytological and histological observations. Vitellogenesis occured by way of endogeous autosynthesis and exogenous heterosynthesis: vitellogensis occurred through a process of autosynthesis, which involves a combined activities of the Golgi complex, mitochondria, and rough endoplasmic reticulum. The process of heterosynthesis involved endocytotic incorporation of extraovarian precursors into the basal region of the early vitellogenic oocytes prior to the formation of vitelline envelope. The follicle cells appear to play an integral role in vitellogenesis and oocyte degeneration, functioning in phagocytosis and digestion of products originating from the degenerated oocytes: these functions can permit the transfer of yolk precursors needed for vitellogenesis. Follicle cells might have a lysosomal system for breakdown and might also resorb phagosomes in the cytoplasm for nutrient storage during oocyte degeneration.

• BMB Reports
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• 제56권1호
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• pp.2-9
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• 2023

Hair follicles in the skin undergo cyclic rounds of regeneration, degeneration, and rest throughout life. Stem cells residing in hair follicles play a pivotal role in maintaining tissue homeostasis and hair growth cycles. Research on hair follicle aging and age-related hair loss has demonstrated that a decline in hair follicle stem cell (HFSC) activity with aging can decrease the regeneration capacity of hair follicles. This review summarizes our understanding of how age-associated HFSC intrinsic and extrinsic mechanisms can induce HFSC aging and hair loss. In addition, we discuss approaches developed to attenuate ageassociated changes in HFSCs and their niches, thereby promoting hair regrowth.

• Asian-Australasian Journal of Animal Sciences
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• 제20권11호
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• pp.1761-1769
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• 2007

This experiment was conducted to determine the extent to which susceptibility to cortisol-induced follicle shutdown is influenced by fleece phentotype. Twenty Finewool (10 sheep low fibre diameter, low coefficient of fibre diameter-LL and 10 low fibre diameter, high coefficient of variation of fibre diameter-LH) and twenty Strongwool (10 low fibre diameter, low coefficient of variation of fibre diameter-HL and 10 high fibre diameter and high coefficient of variation of fibre diameter-HH) sheep of 9 months of age were individually penned in an animal house and were injected intramuscularly with an aqueous suspension of hydrocortisone acetate at a rate of 1.42 mg/kg body weight for a period of two weeks. Fibre diameter was measured from clipped tattooed patch wool samples. Follicle activity was measured by histological changes in skin biopsies taken weekly. Blood samples were collected at two-week intervals and plasma cortisol measured. Increased plasma cortisol concentration significantly (p<0.05) reduced clean wool production and mean fibre diameter dropped to its lowest level four weeks after commencement and two weeks after the cessation of cortisol injection. Elevation of plasma cortisol concentration significantly (p<0.0001) increased the percentage of inactive follicles two weeks after injection started. High fibre diameter groups (Strongwool sheep; i.e. HL+HH) had significantly (p<0.0001) higher percentage of follicle shutdown than low fibre diameter groups (Finewool sheep; i.e. LL+LH). Average percentage of shutdown follicles for Finewool (LL+LH) and Strongwool (HL+HH) Merino sheep was $9.8{\pm}0.9$ and $13.5{\pm}0.9$ respectively. Shutdown of primary follicles was more pronounced in Finewool than Strongwool sheep. There was no significant effect of coefficient of variation of fibre diameter on propensity to follicle shutdown induced by exogenous cortisol. It is concluded that elevation in plasma cortisol concentration is inhibitory to the normal activity of follicles in Strongwool sheep but that variation in fibre diameter has little or no effect.

• 한국수정란이식학회지
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• 제26권1호
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• pp.1-7
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• 2011

The purpose of this study was to determine the relationship between conception rate and other parameters (body condition score; BCS, progesterone concentrations and follicle size) before estrus induction with CIDR(intravaginal progesterone-releasing controlled internal drug release). The conception rate in cows with < 2.75, 2.75 to 3.25, and 3.25 <, BCS regardless of AI (artificial insemination) time was 46.6%, 63.3%, and 46.6% at CIDR insertion, respectively. The conception rate regardless of BCS was 54.9% in cows inseminated based on detected estrus, and 48.7% in cows inseminated at 72 to 80 hours (timed artificial insemination, TAI) after removal of CIDR. The conception rate regardless of AI time was 40.0% in cows with low progesterone concentrations (less than 1.0 ng/ml), and 56.6% in cows with high progesterone concentrations (more than 1.0 ng/ml) at CIDR injection. The conception rate regardless of progesterone concentrations was 53.8% in cows inseminated based on detected estrus, and 38.0% in cows of TAI after removal of CIDR. The conception rate regardless of AI time was 43.3% in cows with small follicle (less than 5 mm), 53.3% in cows between 5 mm to 10 mm of follicle, and 63.3% in cows with large folliclc (more than 10 mm) at CIDR injection, respectively. The conception rate regardless of follicle size was 58.4% in cows inseminated based on detected estrus, and 45.9% in cows of TAI after removal of CIDR. These results indicated that if the cows with BCS 2.75 to 3.25, active corpus luteum, and/or large dominant follicle (more than 10 mm) are used for estrus induction, the conception rate will be greater.

• 한국패류학회지
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• 제32권1호
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• pp.17-23
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• 2016

암컷 떡조개, Phacosoma japonicus의 난모세포 발달과 보조세포들과 관련된 난황형성과정의 미세구조적 연구를 위해 전자현미경적 관찰에 의해서 조사를 하였다. 난모세포들 내에서의 난황형성과정은 내인성 자율합성과정과 외인성 타가합성에 의해 일어나고 있다. 내인성 자율합성과정을 통해 일어나는 난황형성은 난모세포질 내의 골지복합체, 조면소포체 그리고 미토콘드리아가 결합된 작용에 의해서 일어난다. 그러나 외인성 타가합성과정은 초기난황형성난모세포들의 기저부로 들어오는 난소외부의 난황전구체물질들의 내포작용 (endocytosis)의 결합이 관여하고 있다. 본 연구에서 전난황형성난모세포들과 난황형성난모세포들에 부착된 보조세포들이 용이하게 관찰되었다. 특히, 보조세포들은 영양공급에 의해 전난황형성 난모세포들의 발달에 관여하며, 난황전구체의 엔도시토시스에 의해 초기 및 후기 난황형성 난모세포들 내에서 난황형성에 관여한다. 성숙난모세포에 부착된 보조세포들의 기능은 보조세포들의 세포질 내에서 난황형성을 위해 지질과립들과 글리코겐입자들을 축적한다.

• Asian-Australasian Journal of Animal Sciences
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• 제17권3호
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• pp.313-316
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• 2004

Ultrasonographic studies were conducted on eight Murrah buffaloes daily from day 6 postpartum (pp) onwards till day 77 pp to monitor changes in the cervix, uterine horn and ovarian follicular growth and development. The mean size of horn and cervix on day six ($9.07{\pm}0.74$ and $8.58{\pm}0.00cm$) decreased significantly to $4.09{\pm}0.09$ and $3.56{\pm}0.08cm$ by day 27 pp, respectively. Follicles in 50% of the buffaloes ovulated within 24 to 54 days pp and the size of the largest follicle on different days increased to more than 5 mm. The remaining 50 percent of animals ovulated after 65 days postpartum. Large size follicles (>8.5 mm) appeared in six out of eight buffaloes between 10 to 30 days pp and five animals had ovulated during early postpartum period. Waves pattern of follicular growth was observed during early postpartum period. Ovulatory follicles growth rate was more than the anovulatory follicles and increase in size was more as compared to the subordinate follicle. Anovulatory follicles persisted for longer period. Mean size of large follicle was more from day 6 to 41 pp and again from 50 to 65 pp in cyclic animals. Second large follicle were large during early postpartum (18days), thereafter, its size was more in acyclic animals. Small follicles population was less in cyclic animals upto day 50 postpartum. Mean medium size follicle growth pattern did not differ in cyclic and acyclic groups. Large size follicle number was more in cyclic group (5/8) during 14 to 20 days postpartum. Presence of large follicles (>8.5 mm) showed initiation of ovarian activity.

• 한국임상수의학회지
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• 제15권1호
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• pp.22-29
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• 1998

To investigate the estrual changes of ovaries, appropriate time of mating, diagnosis of early pregnancy after mating, and diagnosis of twin fetuses, ultrasonography was performed in 61 thorough-bred mares (5-12 years old) which had been raised in Chrju island. The followings are the results obtained: 1. The average size of a follicle of mares was $3.2{\times} 3.8cm$ at the beginning of estrus and $4.2{\times} 3.5 cm$ from the middle of estrus to ovulations respectively, and the average size of a follicle and a corpus luteum was $1.8{\times} 1.4 cm and 3.1{\times}2.3 cm$ in the middle of diestrus, respectively. 2. In the result of pregnancy according to mating time after ultrasonographic examination of follicle size, the mares having a follicle of 4.6-5.0 cm (diameter) were mated on the day of ultrasonographic examination or the next day rind all were conceived (3 mares) and another mares having a follicle of 4.1- 4.5cm (diameter) on the 1st or 2nd day after examination and all were conceived (4 mares). 3. By ultrasonographyi early pregnancy in the mares was diagnosed from 12 days of pregnancy and the equine fetus was directly detectable from 23 days of pregnancy, whereas the heartbeat of a fetus was detectable from 28 days of pregnancy. 4. Diagnosis of earl pregnancy of twin was possible from 16 days of pregnancy. These result indicated that ultrasonography is applicable in mares to diagnose the estrual changes of ovaries and the time of ovulation or mating, and to diagnose early pregnancy from 12 days of pregnancy and early pregnancy of twin fetuses.

• Experimental and Molecular Medicine
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• 제50권12호
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• pp.5.1-5.15
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• 2018

Targeting hair follicle regeneration has been investigated for the treatment of hair loss, and fundamental studies investigating stem cells and their niche have been described. However, knowledge of stem cell metabolism and the specific regulation of bioenergetics during the hair regeneration process is currently insufficient. Here, we report the hair regrowth-promoting effect of a newly synthesized novel small molecule, IM176OUT05 (IM), which activates stem cell metabolism. IM facilitated stemness induction and maintenance during an induced pluripotent stem cell generation process. IM treatment mildly inhibited mitochondrial oxidative phosphorylation and concurrently increased glycolysis, which accelerated stemness induction during the early phase of reprogramming. More importantly, the topical application of IM accelerated hair follicle regeneration by stimulating the progression of the hair follicle cycle to the anagen phase and increased the hair follicle number in mice. Furthermore, the stem cell population with a glycolytic metabotype appeared slightly earlier in the IM-treated mice. Stem cell and niche signaling involved in the hair regeneration process was also activated by the IM treatment during the early phase of hair follicle regeneration. Overall, these results show that the novel small molecule IM promotes tissue regeneration, specifically in hair regrowth, by restructuring the metabolic configuration of stem cells.