• Reproductive and Developmental Biology
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• v.29 no.4
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• pp.229-234
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• 2005

Methods for activation of reconstructed oocytes were examined for the production of nuclear transfer (NT) rat embryos using fetal neural stem cells as donor. Neural stem cells were isolated from Day 14.5 rat fetuses, and the oocytes for recipient cytoplasm were recovered from 4-week old Sprague Dawley rats. After enucleation and nuclear injection, the reconstructed oocytes were immediately exposed to activation medium consisting of 10 mM $SrCl_2$ for 4 h (immediate activation after injection; IAI), or cultured in vitro for $2\~3$ h before activation treatment (injection before activation; IBA). Pre-activated oocytes were also used for NT to test reprogramming potential of artificially activated oocytes. The oocytes were grouped as IIA (immediate injection after activation) and ABI (activation $2\~3$ h before injection). Following NT, the oocytes were cultured in vitro. Development of the NT embryos was monitored at 44 and 119 h after activation. The embryos in groups IAI, mA, and IIA were cleaved to the 2-cell stage at the rates of $36.6\%\;(15/41),\;39.5\%\;(17/43)\;and\;46.3\%$ (25/54), respectively. However, in the ABI group, only one embryo ($1.8\%$, 1/55) was cleaved after activation. After in vitro culture, two NT embryos from IAI group had developed to the morula stage $(4.9\%\cdot2/41)$. However, no morula or blastocyst was obtained in the other groups. These results suggest that immediate activation after injection (IAI) method may be used for the production of rat somatic cell NT embryos.

• Preventive Nutrition and Food Science
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• v.12 no.1
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• pp.11-15
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• 2007

This study was conducted to evaluate the influence of diets containing genistein and soy extract on the growth of MDA-MB-231 cells implanted into female Balb/c mice. Four-week-old female athymic nude mice (Balb/c) were acclimated to an AIN-93G control diet for 1 week and then injected MDA-MB-231 cells ($1{\times}10^6$/site) and were continued on the on AIN-93G control diet. Five weeks after injecting the MDA-MB-231 cells ($1{\times}10^6$/site), two experimental groups were assigned to diets containing genistein (750 ${\mu}g/g$ AIN-93G diet) or 0.6% soy extract (containing genistein at 750 ${\mu}g/g$ AIN-93G diet) until they were sacrificed. Tumor growth was significantly reduced in the groups treated with genistein and soy extract compared to the control group. The results of the proliferating cell nuclear antigen (PCNA) assay also revealed that genistein and soy extract treatment reduced the proliferation of MDA-MB-231 cells in vivo. In the present study, dietary isoflavone was provided just before solid tumor formation, and thus the timing of dietary isoflavone administration may be critical to the suppression of tumor growth.

• Journal of the Optical Society of Korea
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• v.19 no.2
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• pp.175-181
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• 2015

Optical coherence tomography (OCT) is a noninvasive technique for microscopic investigation of tissue. We thought that the OCT method could be a potential tool for monitoring the healing process of a tendon. In this study we used two rat models, denervated and non-denervated groups, to observe a variety of healing phases of Achilles tendon (AT) injury. We made samples of AT injury lesions, to take OCT images and to make histopathological samples of serial sectional tissue. In an OCT image the denervated rat showed no specific finding, but the non-denervated rat showed a large defect lesion that was scaffolding tissue. OCT findings combined with pathologic findings showed advantages in visualization of tendon microstructure over other imaging modalities such as MRI and US, and OCT is beneficial to making a treatment plan, especially the timing and intensity of rehabilitation. Therefore a multimodal platform using OCT for evaluation of tendon injury may be potentially useful for many applications.

• Korean Journal of Cleft Lip And Palate
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• v.3 no.2
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• pp.67-73
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• 2000

The purpose of this survey was to obtain an overall view of the status of cleft lip and palate management in Oral and Maxillofacial Surgery(OMFS) in Korea. Korea Cleft lip and Palate Association conducted mailed survey which was composed of 29 questions conceming pre-operative and post-operative management in CLP surgery and completed by 58 training hospital. Of 58 questionnaires sent, 23 were returned(response rate of 40%). Authors compared this results with those of other similar surneys, which reveal much difference between OMFS and Plastic Surgery(PS) in CLP treatment. In OMFS, many surgeons were in favor of presugical orthopaedics than lip adhesion to manage protruded premaxilla. It reflects interdisciplinary team approach between OMFS and orthodontic department reduces the need of lip adhesion through presurgical orthopaedics. Timing of palatal surgery was later than that of PS, which reflects concern for an impediment of maxillaty growth. To our knowledge, this survey may be the first on organization and management for cleft patient in OMFS in Korea.

• Journal of Labour Economics
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• v.43 no.4
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• pp.35-86
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• 2020

We estimate the effects of marriage on women's labor market outcomes and subject well-being. To resolve the endogeneity problem of marital status and timing of marriage, we use the difference-in-differences event study method which compares the trends of the outcome before and after the event between treatment and control groups. For robustness, we use four different control groups. The results show that the probability of working drops significantly by about 10%p in the first year of marriage and the effect becomes as large as 46%p by the 5th year of marriage. Also monthly earnings decrease substantially. We find that marriage increases subjective well-being, while the effect is not persistent.

• Clinical and Experimental Pediatrics
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• v.62 no.5
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• pp.155-161
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• 2019

Following the first successful trial of surfactant replacement therapy for preterm infants with respiratory distress syndrome (RDS) by Fujiwara in 1980, several animal-derived natural surfactants and synthetic surfactants have been developed. Synthetic surfactants were designed to overcome limitations of natural surfactants such as cost, immune reactions, and infections elicited by animal proteins contained in natural surfactants. However, first-generation synthetic surfactants that are protein-free have failed to prove their superiority over natural surfactants because they lack surfactant protein (SP). Lucinactant, a second-generation synthetic surfactant containing the SP-B analog, was better or at least as effective as the natural surfactant, suggesting that lucinactant could act an alternative to natural surfactants. Lucinactant was approved by the U. S. Food and Drug Administration in March 2012 as the fifth surfactant to treat neonatal RDS. CHF5633, a second-generation synthetic surfactant containing SP-B and SP-C analogs, was effective and safe in a human multicenter cohort study for preterm infants. Many comparative studies of natural surfactants used worldwide have reported different efficacies for different preparations. However, these differences are believed to due to site variations, not actual differences. The more important thing than the composition of the surfactant in improving outcome is the timing and mode of administration of the surfactant. Novel synthetic surfactants containing synthetic phospholipid incorporated with SP-B and SP-C analogs will potentially represent alternatives to natural surfactants in the future, while improvement of treatment modalities with less-invasive or noninvasive methods of surfactant administration will be the most important task to be resolved.

• Journal of Chest Surgery
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• v.55 no.4
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• pp.265-273
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• 2022

Lung transplantation is considered a viable treatment option for patients with end-stage lung disease. Recent decades have seen a gradual increase in the number of lung transplantation patients worldwide, and in South Korea, the case number has increased at least 3-fold during the last decade. Furthermore, the waiting list time is becoming longer, and more elderly patients (>65 years) are undergoing lung transplantation; that is, the patients placed on the waiting list are older and sicker than in the past. Hence, proper management during the pre-transplantation period, as well as careful selection of candidates, is a key factor for transplant success and patient survival. Although referring and transplant centers should address many issues, the main areas of focus should be the timing of referral, nutrition, pulmonary rehabilitation, critical care (including mechanical ventilation and extracorporeal membrane oxygenation), psychological support, and the management of preexisting comorbid conditions (coronary artery disease, diabetes mellitus, gastroesophageal reflux disease, osteoporosis, malignancy, viral infections, and chronic infections). In this context, the present article reviews and summarizes the pre-transplantation management strategies for adult patients listed for lung transplantation.

• Journal of Ecology and Environment
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• v.46 no.3
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• pp.243-249
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• 2022

Background: Mixed breeding herb Viola collina Besser, which produces both chasmogamous and cleistogamous flower, has limited habitats under closed canopy and short and early flowering timing, making it relatively more vulnerable to climate change. To better understand the effect of light and nutrient on the flower formation and vegetative growth of V. collina, a mesocosm experiment was conducted. Two-by-two factorial treatments of two light conditions (100% and 60% of natural light) and two fertilizer treatment conditions (fertilized and not fertilized) were applied in the mesocosm experiment. Results: The number of flowers, including chamogamous and cleistogamous flowers, was highest (5.65/pot) under 60% light and fertilized condition and lowest (1.41/pot) under 100% light and not-fertilized condition. However, above ground vegetative growth was highest (2.89 g/pot) under 100% light and fertilized condition and lowest (2.38 g/pot) under 60% light and not-fertilized condition. Above ground biomass to belowground biomass ratio was highest (1.50) under 60% light and fertilized condition and lowest (1.26) under 100% light and fertilized condition. Conclusions: This study showed that high light and nutrient are responsible for the vegetative growth, though the effect of fertilizer was reduced due to allocation and retainment of nutrients. In addition, the low light is necessary to make flowers, especially chasmogamous flowers.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.45 no.3
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• pp.139-149
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• 2022

Korea's Corona 19(COVID-19) quarantine, referred to as 'K-Quarantine', is a globally recognized quarantine system that has achieved both conflicting goals: health and economy. The quarantine system represented by 3T(Test-Trace-Treat) is not a method of blocking an area, but a method of screening and treating infected and non-infected persons. The screening center, one of the key elements of this screening treatment system, has evolved to suit the timing and situation of COVID-19, and has succeeded in initial response by conducting large-scale tests quickly and safely. By analyzing the evolution of screening centers that produced such significant results from a problem-solving point of view, it proved its meaning as a practical success case of creative problem-solving. In addition, the usefulness of TRIZ (Russian abbreviation of Theory of Solving Inventive Problem), a creative problem-solving theory, was confirmed through an analysis of actual verified cases of COVID-19 response. TRIZ is a problem-solving theory created by analyzing the regularity of invention patents, and is widely used not only in the technical field but also in the non-technical fields such as design, management, and education. The results of this study are expected to provide useful meaning and practical examples to researchers interested in system analysis and TRIZ application from a problem-solving perspective.

• Archives of Obesity and Metabolism
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• v.2 no.2
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• pp.54-63
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• 2023

Estrogen is crucial in regulating food intake, energy expenditure, glucose metabolism, and lipid metabolism. During menopause, the decline in estrogen levels predisposes women to weight gain, abdominal obesity, insulin resistance, type 2 diabetes, hypertension, and cardiovascular disease (CVD). Menopausal hormone therapy (MHT) prevents weight gain, improves lipid metabolism by lowering low-density lipoprotein cholesterol while raising high-density lipoprotein cholesterol, and delays the onset of type 2 diabetes in menopausal women. The effect of MHT on CVD in menopausal women remains controversial. The Women's Health Initiative study was terminated prematurely after it revealed that hormone administration increased the risk of myocardial infarction, stroke, and thromboembolism. However, some studies have found that MHT had no effect or decreased the risk of CVD. The inconsistent results were likely due to multiple factors, including the timing of hormone therapy initiation, duration of therapy, type and dosage, and presence or absence of CVD risk factors at the start of treatment. Despite its benefits in terms of managing weight gain and reducing the risk of type 2 diabetes, dyslipidemia, and CVD associated with obesity, it is not recommended as the primary therapy for weight loss or diabetes prevention. MHT is primarily indicated for postmenopausal women, who are likely to benefit from its potential to prevent weight gain and improve lipid metabolism.