• Journal of the korean academy of Pediatric Dentistry
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• v.49 no.3
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• pp.340-347
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• 2022

Distal displacement of the tooth germ of the mandibular second premolar (MnP2) leads to its impaction and obturation of the eruption path of the mandibular first molar delaying its eruption. The present case report describes the treatment of 2 cases of eruption guidance for distally displaced developing MnP2 that caused delayed eruption of the mandibular first molar. Intentional extraction of primary predecessor results in the mesial shift of the displaced MnP2. However, unfavorable distal ectopic eruption of the mandibular first premolar after the premature loss of primary second molar has been previously reported. Hemisection and sequential extraction of the mandibular primary second molar were performed to mesially shift the distally displaced MnP2, while preventing unfavorable distal ectopic eruption of the mandibular first premolar.

• The Korea Journal of Herbology
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• v.29 no.1
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• pp.7-12
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• 2014

Objectives : Polygoni Multiflori Radix (PMR), the roots of Polygonum multiflorum Thunberg, is used to nourish the blood and yin and used for preventing premature greying of the hair. There are some articles on its preventing effects on the melanogenesis. However, there is no report about its effects on the collagen and elastin. The present study was designed to investigate its effects on collagen metabolism and elastase activity. Methods : The effects of PMR on type I procollagen production and collagenase activity in human normal fibroblasts Hs68 after UVB (312 nm) irradiation were measured by ELISA method. Cells were pretreated with the PMR for 24 hours prior to UVB irradiation. After UVB irradiation, cells were retreated with the sample and incubated for additional 24 hours. The amount of collagen type I was measured with a procollagen type I C-peptide assay kit. The activity of collagenase was measured with a MMP-1 human biotrak ELISA system. The elastase activities after treatment of PMR were measured as well. Results : In the present study, the collagen production was not increased. However, the increased collagenase activity after UVB damage was significantly recovered to $50.2{\pm}14.5%$, $8.2{\pm}3.1%$, and $10.0{\pm}3.3%$ (10, 30, and $100{\mu}g/ml$). The elastase activities (10, 100, and $1000{\mu}g/ml$) significantly reduced to $75.2{\pm}5.2%$, $40.3{\pm}1.2%$, and $27.0{\pm}1.9%$, respectively. Conclusion : PMR showed the inhibitory effects on collagenase and elastase activity. These results suggest that PMR may have potential as an anti-aging ingredient in cosmetic herbal treatment.

• Clinical and Experimental Reproductive Medicine
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• v.49 no.3
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• pp.210-214
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• 2022

Objective: Platelet-rich plasma (PRP) therapy has received a considerable attention as an adjunct to fertility treatments, especially in women with very low ovarian reserve and premature ovarian insufficiency. Although recent studies have demonstrated that PRP led to improvements in folliculogenesis and biomarkers of ovarian reserve, the effect of intraovarian PRP administration on embryo genetics has not been studied. Methods: We report a pilot study of patients who had preimplantation genetic testing for aneuploidy (PGT-A) before and then within 3 months following PRP administration. Twelve infertile women with at least one prior failed in vitro fertilization (IVF) cycle underwent ovarian stimulation (cycle 1) with a gentle stimulation protocol and PGT-A performed at the blastocyst stage. Following cycle 1, autologous intraovarian PRP administration was performed. Within 3 months following PRP administration, the patients underwent cycle 2 and produced blastocysts for PGT-A. The percentage of euploid embryos between both cycles was compared. Results: The mean age of all participants was 40.08±1.46 years, and their mean body mass index was 26.18±1.18 kg/m². The number of good-quality embryos formed at the blastocyst stage was similar between cycle 1 and cycle 2 (3.08±0.88 vs. 2.17±0.49, respectively; p=0.11). Among all patients in cycle 1, 3 of 37 embryos were euploid (8.11%) while in cycle 2, 11 out of 28 embryos were euploid (39.28%, p=0.002). Three clinical pregnancies were noted among this patient group. Conclusion: This novel study is the first to present an improvement in the embryo euploidy rate following intraovarian PRP application in infertile women with prior failed IVF cycles. The growth factors present in PRP may exhibit a local paracrine effect that could improve meiotic aberrations in human oocytes and thus improve euploidy rates. Whether PRP improves live birth rates and lowers miscarriage rates remains to be determined in large trials.

• Steel and Composite Structures
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• v.43 no.1
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• pp.19-30
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• 2022

The static strength and fatigue crack resistance of the aircraft skin structures depend on the materials used and joint type. Most of the commercial aircraft's skin panel structures are made from aluminium alloy and carbon fibre reinforced epoxy. In this study, the fatigue resistance of four joint configurations (metal/metal, metal/composite, composite/composite and composite/metal) with riveted, adhesive bonded, and hybrid joining techniques are investigated with experiments and finite element analysis. The fatigue tests were tension-tension because of the typical nature of the loads on aircraft skin panels susceptible of experimenting fatigue. Experiment results suggest that the fatigue life of hybrid joints is superior to adhesive bonded joints, and these in turn much better than conventional riveted joints. Thanks to the fact that, for hybrid joints, the adhesive bond provides better load distribution and ensures load-carrying capacity in the event of premature adhesive failure while rivets induce compressive residual stresses in the joint. Results from FE tool ABAQUS analysis for adhesive bonded and hybrid joints agrees with the experiments. From the analysis, the energy release rate for adhesive bonded joints is higher than that of hybrid joints in both opening (mode I) and shear direction (mode II). Most joints show higher energy release rate in mode II. This indicates that the joints experience fatigue crack in the shear direction, which is responsible for crack opening.

• Molecules and Cells
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• v.45 no.9
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• pp.660-672
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• 2022

The target of rapamycin complex (TORC) plays a key role in plant cell growth and survival by regulating the gene expression and metabolism according to environmental information. TORC activates transcription, mRNA translation, and anabolic processes under favorable conditions, thereby promoting plant growth and development. Tomato fruit ripening is a complex developmental process promoted by ethylene and specific transcription factors. TORC is known to modulate leaf senescence in tomato. In this study, we investigated the function of TORC in tomato fruit ripening using virus-induced gene silencing (VIGS) of the TORC genes, TOR, lethal with SEC13 protein 8 (LST8), and regulatory-associated protein of TOR (RAPTOR). Quantitative reverse transcription-polymerase chain reaction showed that the expression levels of tomato TORC genes were the highest in the orange stage during fruit development in Micro-Tom tomato. VIGS of these TORC genes using stage 2 tomato accelerated fruit ripening with premature orange/red coloring and decreased fruit growth, when control tobacco rattle virus 2 (TRV2)-myc fruits reached the mature green stage. TORC-deficient fruits showed early accumulation of carotenoid lycopene and reduced cellulose deposition in pericarp cell walls. The early ripening fruits had higher levels of transcripts related to fruit ripening transcription factors, ethylene biosynthesis, carotenoid synthesis, and cell wall modification. Finally, the early ripening phenotype in Micro-Tom tomato was reproduced in the commercial cultivar Moneymaker tomato by VIGS of the TORC genes. Collectively, these results demonstrate that TORC plays an important role in tomato fruit ripening by modulating the transcription of various ripening-related genes.

• Korean Journal of Clinical Pharmacy
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• v.32 no.3
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• pp.191-203
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• 2022

Background: Direct-acting antivirals are recommended for the treatment of chronic hepatitis C virus in Korea. However, evaluation of direct-acting antiviral regimens in a real-world setting is limited. The aims of this study were to investigate the effectiveness and safety of direct-acting antiviral treatment in Korean patients infected with chronic hepatitis C virus genotype 1b or 2 at a tertiary care hospital. Methods: This was a retrospective study conducted with patient data obtained between August 2015 and August 2019 at Jeonbuk National University Hospital. The primary effectiveness endpoint was sustained virological response 12 weeks post-treatment (SVR12) via intention-to-treat (ITT) and modified intention-to-treat (mITT) analyses. Results: Of the 270 patients, 47.0% were infected with genotype 1b and 53.0% with genotype 2. ITT analysis revealed that SVR12 was achieved in 78.9% of all patients, 77.2% in genotype 1b patients, and 80.4% in genotype 2 patients. Of the 21.1% of all patients who did not achieve SVR12, the majority of treatment failures were non-virologic failures (19.7%). mITT analysis revealed that SVR12 was achieved in 98.2% of all patients, 98.0% in genotype 1b patients, and 98.3% in genotype 2 patients. Almost half of all patients experienced one or more adverse events (43.3%), leading to 2.6% discontinuing scheduled treatment. The most common adverse event was anemia. Conclusions: Direct-acting antiviral-based treatment regimens showed high effectiveness and safety. Non-virological factors, such as premature treatment discontinuation due to adverse events or loss of follow-up, were the major disruptors in achieving SVR12.

• Clinical and Experimental Pediatrics
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• v.65 no.5
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• pp.262-268
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• 2022

Background: The delayed diagnosis of developmental dysplasia of the hip (DDH) requires complex treatment and sometimes progresses to hip osteoarthritis. Purpose: This study aimed to evaluate the risk factors and screening time for DDH in preterm infants. Methods: A total of 155 preterm infants with a gestational age <32 weeks screened for DDH with ultrasonography were enrolled in this retrospective chart review. Results: The incidence of DDH was 6.45% (10 of 155). Gestational age, birth weight, sex ratio, and breech presentation did not differ significantly between infants treated for DDH (n=10) and nontreated infants (n=145) (gestational age, 29.2±1.4 weeks vs. 29.6±2.0 weeks, P=0.583; birth weight, 1,240±237 g vs. 1,295±335 g, P=0.607; female sex, 7 of 10 (70.0%) vs. 77 of 145 (53.1%), P=0.346; and breech presentation, 5 of 10 (50.0%) vs. 43 of 145 (29.7%), P=0.286, respectively). Performing the first ultrasonography earlier than 38 weeks of postmenstrual age (PMA) increased the risk of an abnormal finding by 3.76 times compared to performing it at ≥38 weeks of PMA. These abnormal findings on ultrasonography resolved spontaneously. Breech presentation increased the risk of minor abnormal findings on the first ultrasonography by 3.11 times versus nonbreech presentation and resolved spontaneously. DDH in preterm infants did not occur predominantly on the left side or in infants born with breech presentation. Conclusion: Performing ultrasonography screening earlier than 38 weeks of PMA caused unnecessary subsequent ultrasonography and overtreatment. Breech presentation was not a risk factor for DDH in preterm infants. However, breech presentation could increase the risk of minor abnormal findings at the 1st ultrasonography compared to nonbreech presentation, which resolved spontaneously. The etiology and risk factors for DDH in preterm infants are somewhat different from those for DDH in term infants.

• Clinical and Experimental Pediatrics
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• v.65 no.4
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• pp.172-181
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• 2022

Pubertal onset is known to result from reactivation of the hypothalamic-pituitary-gonadal (HPG) axis, which is controlled by complex interactions of genetic and nongenetic factors. Most cases of precocious puberty (PP) are diagnosed as central PP (CPP), defined as premature activation of the HPG axis. The cause of CPP in most girls is not identifiable and, thus, referred to as idiopathic CPP (ICPP), whereas boys are more likely to have an organic lesion in the brain. ICPP has a genetic background, as supported by studies showing that maternal age at menarche is associated with pubertal timing in their offspring. A gain of expression in the kisspeptin gene (KISS1), gain-of-function mutation in the kisspeptin receptor gene (KISS1R), loss-of-function mutation in makorin ring finger protein 3 (MKRN3), and loss-of-function mutations in the delta-like homolog 1 gene (DLK1) have been associated with ICPP. Other genes, such as gamma-aminobutyric acid receptor subunit alpha-1 (GABRA1), lin-28 homolog B (LIN28B), neuropeptide Y (NPYR), tachykinin 3 (TAC3), and tachykinin receptor 3 (TACR3), have been implicated in the progression of ICPP, although their relationships require elucidation. Environmental and socioeconomic factors may also be correlated with ICPP. In the progression of CPP, epigenetic factors such as DNA methylation, histone posttranslational modifications, and non-coding ribonucleic acids may mediate the relationship between genetic and environmental factors. CPP is correlated with short- and long-term adverse health outcomes, which forms the rationale for research focusing on understanding its genetic and nongenetic factors.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.338-351
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• 2003

UV radiation is the most dangerous stress factor among permanent environmental impacts on human skin. Consequences of UV exposure are aberrant tissue architecture, alterations in skin cells including functional changes. Nowadays new kinds of outdoor leisure-time activities and changing environmental conditions make the question of sun protection more important than ever. It is necessary to recognize that self-confident consumers do not consider to change their way of life, they demand modern solutions on the basis of new scientific developments. In the past one fundamental principle of cosmetics was the use of physical and organic filter systems against damaging UV-rays. Today new research results demonstrate that natural protecting cell mechanisms can be activated. Suitable biological actives strongly support the protection function not from the surface but from the inside of the cell. A soy seed preparation (SSP) was proven to stimulate natural skin protective functions. The major functions are an increased energy level and the prevention of DNA damage. These functions can I be defined as biological UV protection. The tumor suppressor protein p53 plays a key role in the regulation of DNA repair. p53 must be transferred into the phosphorylated form to work as transcription factor for genes which are regulating the cell cycle or organizing DNA repair. A pretreatment with SSP increases the phosphorylation rate of p53 of chronically UV-irradiated human keratinocytes significantly. According to the same test procedure SSP induces a dramatic increase in the expression of the tumor suppressor protein p14$^{ARF}$ that is supporting the p53 activity by blocking the antagonist of p53, the oncoprotein Mdm2. Mdm2, a ubiquitin E3-ligase, downregulates p53 and at the same time it prevents phosphorylation of p53. The positive influence of the tumor suppressor proteins explains the stimulation of DNA repair and prevention of sunburn cell formation by SSP, which was proven in cell culture experiments. In vivo the increased skin tolerance against UV irradiation by SSP could be confirmed too. We have assumed, that an increased repair potential provides full cell functionality.y.

• Steel and Composite Structures
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• v.46 no.4
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• pp.497-512
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• 2023

Using light weight concrete as infill material in conventional cold-formed steel (CFS) shear wall systems can considerably increase their load bearing capacity, ductility, integrity and fire resistance. The compressive strength of the filler concrete is a key factor affecting the structural behaviour of the composite wall systems, and therefore, achieving maximum compressive strength in lightweight concrete while maintaining its lightweight properties is of significant importance. In this study a new type of optimum polystyrene lightweight concrete (OPLC) with high compressive strength is developed for infill material in composite CFS shear wall systems. To study the seismic behaviour of the OPLC-filled CFS shear wall systems, two full scale wall specimens are tested under cyclic loading condition. The effects of OPLC on load-bearing capacity, failure mode, ductility, energy dissipation capacity, and stiffness degradation of the walls are investigated. It is shown that the use of OPLC as infill in CFS shear walls can considerably improve their seismic performance by: (i) preventing the premature buckling of the stud members, and (ii) changing the dominant failure mode from brittle to ductile thanks to the bond-slip behaviour between OPLC and CFS studs. It is also shown that the design equations proposed by EC8 and ACI 318-14 standards overestimate the shear force capacity of OPLC-filled CFS shear wall systems by up to 80%. This shows it is necessary to propose methods with higher efficiency to predict the capacity of these systems for practical applications.