• Journal of the Korean Orthopaedic Association
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• v.55 no.2
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• pp.143-153
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• 2020

Purpose: To evaluate the timing of the improvement in surgical skills of the direct anterior approach for hip arthroplasty through an analysis of the clinical features and learning curve in 58 cases. Materials and Methods: From November 2016 to November 2018, 58 patients, who were divided into an early half and late half, and underwent hip arthroplasty by the direct anterior approach, were enrolled in this retrospective study. The operation time and complications (fracture, lateral femoral cutaneous nerve injury, heterotopic ossification, infection, and dislocation) were assessed using a chi-square test, paired t-test, and cumulative sum (CUSUM) test. Results: The mean operation times in total hip arthroplasty (26 cases) and bipolar hemi-arthroplasty were 132.1 minutes and 79.7 minutes, respectively, demonstrating a significant difference between the two groups. CUSUM analysis based on the results revealed breakthrough points of the operation time, decreasing to less than the mean operation time because of the 16th case in total hip arthroplasty and 14th case in bipolar hemiarthroplasty. Complications were encountered in the early phase and late phase: five cases of fractures in the early phase, no case in the late phase; eight and two cases of lateral femoral cutaneous nerve injury, respectively; three and two cases of heterotopic ossification, respectively; and one case of dislocation, one case of infection and three cases of others in the early phase. The CUSUM chart for the fracture rate during operation in the early phase revealed the following: five cases fracture (17.2%) in the early phase and no case in the late phase (0%). This highlights the learning curve and the need for monitoring the inadequacy of operation based on the complications. Conclusion: Hip arthroplasty performed by the direct anterior approach based on an anatomical understanding makes it difficult to observe the surgical field and requires a learning curve of at least 30 cases.

• BMB Reports
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• v.53 no.3
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• pp.148-153
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• 2020

Erythropoietin and iron have individually shown beneficial effects on early-phase liver regeneration following partial hepatectomy (PHx); however, there are limited data on the combined effect on late-phase liver regeneration after PHx. Here we examined combined effects of recombinant human erythropoietin (rhEPO, 3,000 IU/kg) and iron isomaltoside (IIM, 40 mg/kg) on late-phase liver regeneration following PHx and investigated the possible underlying mechanism. Rats administrated with rhEPO showed significantly higher liver mass restoration, interleukin-6 (IL-6, a hepatocyte mitogen) levels, and Ki-67-positive hepatocytes on day 7 after PHx than saline-treated controls. These beneficial effects were further enhanced on days 7 and 14 by co-treatment with IIM. This combination also significantly improved liver function indices, such as increased albumin production and decreased bilirubin levels, but did not alter serum levels of toxic parameters, such as aspartate transaminase and alanine transaminase. This study demonstrates that the combination of rhEPO and IIM synergistically improves late-phase liver regeneration and function after PHx, probably by promoting IL-6-mediated hepatocyte proliferation without adverse effects. Thus, this combination treatment can be a potential therapeutic strategy for patients undergoing resection for hepatic malignancies.

• Journal of Aquaculture
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• v.2 no.1
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• pp.21-32
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• 1989

This study was undertaken to understand development stage of ovary and changes of hormone concentrations in the Israeli carp, Cyprinus carpio from Ferbruary to May. The results obtained in these experiments are as follows: 1. Serum LH levels began to increase sharply in March, coinciding with the onset of rapid ovarian development. 2. LH levels were well correlated with changes in gonadosomatic index. 3. Dramatic increase in gonadosomatic index occured during the months of March. 4. Ripe stage(Stage VII) rapidly increase in March. 5. Early perinucleolus oocyte rapidly develop into late perinucleolus oocytes in March. 6. The vitellogenic phase begins as these late perinucleolus oocytes become transformed into early maturing oocytes through the accumulation of yolk. 7. The cytoplasm completely fills with yolk as oocytes reach the late maturing stage. 8. Changes in the microscopic appearances of the ovaries were well correlated with changes in both gonadosomatic index and macroscopic appearance. 9. It is concluded from these observations that LH plays a major role in sexual maturating of the Israeli carp.

• Biomolecules & Therapeutics
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• v.25 no.6
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• pp.569-577
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• 2017

Sepsis is a syndrome characterized by systemic inflammatory responses to a severe infection. Acute hyper-inflammatory reactions in the acute phase of sepsis have been considered as a primary reason for organ dysfunction and mortality, and advances in emergency intervention and improved intensive care management have reduced mortalities in the early phase. However it has been recognized that increased deaths in the late phase still maintain sepsis mortality high worldwide. Patients recovered from early severe illness are unable to control immune system with sepsis-induced immunosuppression such as immunological tolerance, exhaustion and apoptosis, which make them vulnerable to nosocomial and opportunistic infections ultimately leading to threat to life. Based on strategies to reverse immunosuppression, recent developments in sepsis therapy are focused on molecules having immune enhancing activities. These efforts are focused on defining and revising the immunocompromised status associated with long-term mortality.

• Korean Journal of Applied Biomechanics
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• v.26 no.2
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• pp.161-166
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• 2016

Objective: The purpose of this study was to determine the knee and ankle joint kinematics and kinetics by comparing downhill walking with valley-shape combined slope walking. Method: Eighteen healthy men participated in this study. A three-dimensional motion capture system equipped with eight infrared cameras and a synchronized force plate, which was embedded in the sloped walkway, was used. Obtained kinematic and kinetic parameters were compared using paired two-tailed Student's t-tests at a significance level of 0.05. Results: The knee flexion angle after the mid-stance phase, the mean peak knee flexion angle in the early swing phase, and the ankle mean peak dorsiflexion angle were greater during downhill walking compared with valley-shape combined slope walking (p < 0.001). Both the mean peak vertical ground reaction force (GRF) in the early stance phase and late stance phase during downhill walking were smaller than those values during valley-shape combined slope walking. (p = 0.007 and p < 0.001, respectively). The mean peak anterior GRF, appearing right after toe-off during downhill walking, was also smaller than that of valley-shape combined slope walking (p = 0.002). The mean peak knee extension moment and ankle plantar flexion moment in late stance phase during downhill walking were significantly smaller than those of valley-shape combined slope walking (p = 0.002 and p = 0.015, respectively). Conclusion: These results suggest that gait strategy was modified during valley-shape combined slope walking when compared with continuous downhill walking in order to gain the propulsion for lifting the body up the incline for foot clearance.

• Reproductive and Developmental Biology
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• v.35 no.2
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• pp.175-183
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• 2011

The present study compared the developmental potential, telomerase activity and transcript levels of X-linked genes (ANT3, HPRT, MeCP2, RPS4X, XIAP, XIST and ZFX) in the bovine somatic cell nuclear transfer (SCNT) embryos derived from different age and cell cycle of female donor nucleus. In experiment 1, the fusion rate, cleavage rate to 2-cell stage, developmental rate to blastocyst stage, and the mean number of total and ICM cells was slightly increased in embryos cloned with fetal fibroblasts compared to those with adult fibroblasts, but there was no significantly (p<0.05) differences. Telomerase activity was also similar in blastocysts cloned with fetal and adult fibroblasts. Up-regulated RPS4X and down-regulated MeCP2, XIAP, and XIST transcript level were observed in blastocysts cloned with adult fibroblasts, compared to those with fetal fibroblasts. In experiment 2, the fusion rate, cleavage rate to 2-cell stage, developmental rate to blastocyst stage, and the mean number of total and ICM cells was significantly (p<0.05) increased in embryos cloned with fetal fibroblasts at early G1 phase of the cell cycle, compared to those of fetal fibroblasts at late G1 phase. DNMT1 transcript was observed to significantly (p<0.05) increased in the fetal fibroblasts at 3 hrs after trypsin treatment of confluent culture. Further, level of telomerase activity and transcribed X-linked genes was also significantly (p<0.05) higher in the early G1 SCNT blastocysts than those of late G1. The results imply that fetal fibroblasts at early G1 phase induces the enhanced developmental potential and up-regulated telomerase activity and X-linked gene, but aberrant transcript pattern of X-linked genes may be displayed in the SCNT embryos.

• Biomedical Science Letters
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• v.2 no.1
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• pp.57-69
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• 1996

To examine the process of spermiogenesis in the Korean red-backed vole, Clethrionomys rufocanus regulus, the seminiferous epithelium in the testis, was studied by trasmission electron microscopy, and the following results were obtained based on the morphological characteristics of cell differentiation. 1. According to the fine structural differentiation, spermiogenesis was divided into Golgi, cap, acrosome, maturation and spermiation phases. Besides, these phases were sub-divided into two steps : early and late phases respectively, Thus, the spermiogenesis of Clethrionomys rufocanus regulus was divided into a total of ten steps. 2. In the changes of the chromatin, the chromatin granules began to be condenced in the late Golgi phase, regularizated at maturation phases, and a perfect nucleus of sperm was formed at the spermiation phases. 3. The sperm head had the falciform, and the formative period of sperm tail began to be develop in the early Golgi phase and completed at the spermiation phases. 4. In the morphological features of spermiation phases, the spermatid of early spermiation phase was divided into three types : (1) A-type spermatid contained cytoplasmic droplets in the neck region and middle piece, and the mitochondria was irregular, and arranged around the axoneme. (2) B-type contained cytoplasmic droplet in the middle piece only, and the mitochondria are arranged the center of axoneme regularly, and (3) In the C-type spermatid, the arrangement of mitochondria was regular, and was contained cytoplasmic droplet in the neck region only. In the late spermiation phase, only the sperm head was surrounded by cytoplasm of Sertoli cell or the matured sperm just before the spermiation from the cytoplasm of Sertoli cell.

• The Korean Journal of Physiology
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• v.20 no.1
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• pp.89-102
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• 1986

It has long been suggested that the change of renin-angiotensin system is responsible for the increased arterial blood pressure in the experimental hypertension. But the exact nature of the cause and maintenance of early and late Phase of renal hypertension is still controversial. Increased renin-angiotensin system has been suggested. To clarify the altered renin-angiotensin system in the early phase of two kidney one clip Goldblatt hypertension(2K1C GH), experiments were carried out in the rats of 3,7, and 14 days of 2K1C GH rats, sham-operated, and control rats. Responses of the plasma renin activity to the intravenous infusion of L-isoproterenol were dose-dependent. Responses of the plasma renin activity to the intravenous L-isoproterenol in 2K1C GH rats were not different from sham-operated control rats. Hypotensive responses of the 2K1C GH rats were not different from sham-operated rats. Suppression by intravenous infusion of angiotensin II of plasma renin activity showed a dose-dependent manner. Suppression by angiotensin ll of plasma renin activity was attenuated or abolished in the early phase of 2K1C GH rats. Intravenous infusion of arginine vasopressin(AVP) showed a dose-dependent suppression of plasma renin activity, Attenuated responses by AVP of plasma renin activity were noticed in the early phase of 2K1C GH rats. These results suggest that the altered renin-angiotensin system in the early phase of the two kidney one clip Goldblatt hypertension may be caused by failure of the short loop negative feedback control mechanism.

• Journal of Life Science
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• v.11 no.4
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• pp.362-370
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• 2001

Regulation of cell proliferation is a complex process involving the regulated expression and /or modification of discrete gene products. which control transition between different stages of the cycle. The purpose of this short review is to provide an overview of somatic cell cycle events and their controls. Cycline have appeared as major positive regulators in this network, because their association to the cyclin-dependent kinases(Cdks) allows the subsequent activation on the Cdk/cyclin complexes and their catalatic activity. In mammalian cells, early to mid G1 progression and late G1 progression leading to S phase entry are directed by D-type cyclins-Cdk4, 6 and cyclin E-Cdk 2 both of which can phosphorylate the retinoblastoma protein (pRB). pRB is a transcriptional repressor which, in its unphosphorylated state, binds to members of the E2F transcription factor family and blocks E2F-dependent transcription of genes controlling the G1 to S phase transition an subsequent DNA synthesis. Cyclin A is produced in late G1 and expressed during S and G2 phae, and expression of B-type cyclins is typically maximal during the G2 to M phase transition and it controls the passage through M phase. They primarily associate with the activate Cdk2, and Cdc2, respectively. On the other hand, the Cdk inhibitors negatively control the activity of C아/cyclin complex by coordinating internal and/or external signals and impending proliferation at several key checkpoints. These current and further findings will provide novel approaches to understanding and treating major diseases.

• Applied Microscopy
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• v.25 no.1
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• pp.96-110
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• 1995

In order to clarify the process of spermiogenesis of the large-footed bat, Myotis macrodactylus, the testis and the epididymis obtained from mature male bats were examined by electron microscope. Based on the variety and diagnostic characters of organells, the spermiogenesis of the large-footed bat. Myotis macrodactylus could be divided into a total of nine phases. The results obtained from the present study are as follows. 1. The spermiogenesis of large-footed bat, Myotis macrodactylus was divided according to the level of fine structural differentiation into five phases, Golgi, cap, acrosome, maturation and spermiation phases, respectively; Golgi, cap, acrosome and spermiation phases were further subdivided into steps of early and late phase respectively and maturation phase has only one step. Hence, the spermiogenesis of the large-footed bat has been divided into a total of nine phases. 2. In the change of chromatin with nucleus, the chromatin granules are condensed in the whole part of nucleus at the late Golgi phase and completed at the maturation phase. 3. The sperm tail in the epididymis consists of nine outer doublets and two central singlet microtubles. Nos. 1, 5, 6, 9 of the outer dense fibers were larger than the others (2, 3, 4, 7, 8).