• The Journal of Advanced Prosthodontics
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• v.2 no.1
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• pp.25-31
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• 2010

PURPOSE. This study compared the accuracy of an abutment-framework (A-F) taken with open tray impression technique combining cement-on crown abutments, a metal framework and resin cement to closed tray and resin-splinted open tray impression techniques for the 3-implant definitive casts. The effect of angulation on the accuracy of these 3 techniques was also evaluated. MATERIAL AND METHODS. Three definitive casts, each with 3 linearly positioned implant analogs at relative angulations 0, 30, and 40 degrees, were fabricated with passively fitted corresponding reference frameworks. Ten impressions were made and poured, using each of the 3 techniques on each of the 3 definitive casts. To record the vertical gap between reference frameworks and analogs in duplicate casts, a light microscope with image processing was used. Data were analyzed by two-way analysis of variance and the Tukey test. RESULTS. The open tray techniques showed significantly smaller vertical gaps compare to closed tray technique (P < .05). The closed tray and the resin-splinted open tray technique showed significantly different vertical gaps according to the angulation of implant (P < .05), but the A-F impression technique did not (P > .05). CONCLUSION. The accuracy of the A-F impression technique was superior to that of conventional techniques, and was not affected by the angulation of the implants.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.4
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• pp.373-382
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• 2015

Fura-2 analogs are ratiometric fluoroprobes that are widely used for the quantitative measurement of [$Ca^{2+}$]. However, the dye usage is intrinsically limited, as the dyes require ultraviolet (UV) excitation, which can also generate great interference, mainly from nicotinamide adenine dinucleotide (NADH) autofluorescence. Specifically, this limitation causes serious problems for the quantitative measurement of mitochondrial [$Ca^{2+}$], as no available ratiometric dyes are excited in the visible range. Thus, NADH interference cannot be avoided during quantitative measurement of [$Ca^{2+}$] because the majority of NADH is located in the mitochondria. The emission intensity ratio of two different excitation wavelengths must be constant when the fluorescent dye concentration is the same. In accordance with this principle, we developed a novel online method that corrected NADH and Fura-2-FF interference. We simultaneously measured multiple parameters, including NADH, [$Ca^{2+}$], and pH/mitochondrial membrane potential; Fura-2-FF for mitochondrial [$Ca^{2+}$] and TMRE for ${\Psi}_m$ or carboxy-SNARF-1 for pH were used. With this novel method, we found that the resting mitochondrial [$Ca^{2+}$] concentration was $1.03{\mu}M$. This $1{\mu}M$ cytosolic $Ca^{2+}$ could theoretically increase to more than 100 mM in mitochondria. However, the mitochondrial [$Ca^{2+}$] increase was limited to ${\sim}30{\mu}M$ in the presence of $1{\mu}M$ cytosolic $Ca^{2+}$. Our method solved the problem of NADH signal contamination during the use of Fura-2 analogs, and therefore the method may be useful when NADH interference is expected.

• Kidney Research and Clinical Practice
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• v.37 no.4
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• pp.384-392
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• 2018

Background: A very low protein diet (VLPD) with ketoacid analogs of essential amino acids (KA/EAA) administration can remarkably influence protein synthesis and metabolic disturbances of patients with advanced chronic kidney disease (CKD), and may also slow the decline in renal function. Methods: A retrospective cohort study was carried out to monitor renal progression and metabolic and nutritional status among 140 patients with CKD stage III or IV. One group (n = 70) was on a low protein diet (LPD) with 0.6 g of protein intake, and another group (n = 70) was on a VLPD with 0.3 g of protein and KA/EAA supplementation of 100 mg/kg/day for 12 months. Results: At 12-month follow-up, estimated glomerular filtration rate (GFR) significantly decreased from $41.6{\pm}10.2$ to $36.4{\pm}8.8mL/min/1.73m^2$ (P < 0.001) and urine protein increased from $0.6{\pm}0.5$ to $0.9{\pm}1.1g/day$ (P = 0.017) in the LPD group, but no significant changes in estimated GFR and urine protein were found in the VLPD plus KA/EAA group. A significant mean difference in rate of change in estimated GFR ($-5.2{\pm}3.6mL/min/1.73m^2$ per year; P < 0.001) was observed between the two groups. After Cox regression analysis, treatment with VLPD plus KA/EAA significantly protected against the incidence of declining GFR > 10% annually (adjusted hazard ratio, 0.42; 95% confidence interval, 0.23-0.79; P = 0.006) and significant correlations were found between using VLPD plus KA/EEA and increased GFR. Conclusion: VLPD supplementation with KA/EAA is associated with delayed renal progression while preserving the nutritional status in the patients with CKD. Co-administration of VLPD and KA/EAA may prove an effective alternative to conservative management of CKD.

• Korean Journal of Food Science and Technology
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• v.53 no.4
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• pp.463-469
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• 2021

Bioactivities of curcumin, a major pigment of Curcuma longa L., have been widely investigated. In this study, the antioxidant and cytotoxic properties of curcumin and its analogs including ferulic acid, dibenzoylmethane (DBM), and tetrahydrocurcumin (THC), and their structure-activity relationships were assessed. Ferulic acid, THC, and curcumin showed strong scavenging activities against several radicals and exhibited considerable lipid peroxidation inhibitory activity. Curcumin showed the strongest cytotoxic activities against HeLa, HCT-116, IEC-6 and INT 407 cells, whereas ferulic acid did not show any cytotoxic effect up to 100 µM against these cell lines. Cytotoxicity of curcumin and THC was significantly enhanced by superoxide dismutase and diminished by N-acetylcysteine. The combination treatment of curcumin and ferulic acid enhanced the cytotoxicity, whereas the combination of curcumin and DBM offset their toxicity. These results suggest that methoxy phenolic and β-diketon moieties are crucial for the antioxidant- and cytototoxic activities of curcumin, respectively.

• Biomolecules & Therapeutics
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• v.29 no.3
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• pp.282-289
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• 2021

A novel coronavirus, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), caused a worldwide pandemic. Our aim in this study is to produce new fusion inhibitors against SARS-CoV-2, which can be the basis for developing new antiviral drugs. The fusion core comprising the heptad repeat domains (HR1 and HR2) of SARS-CoV-2 spike (S) were used to design the peptides. A total of twelve peptides were generated, comprising a short or truncated 24-mer (peptide #1), a long 36-mer peptide (peptide #2), and ten peptide #2 analogs. In contrast to SARS-CoV, SARS-CoV-2 S-mediated cell-cell fusion cannot be inhibited with a minimal length, 24-mer peptide. Peptide #2 demonstrated potent inhibition of SARS-CoV-2 S-mediated cell-cell fusion at 1 µM concentration. Three peptide #2 analogs showed IC50 values in the low micromolar range (4.7-9.8 µM). Peptide #2 inhibited the SARS-CoV-2 pseudovirus assay at IC50=1.49 µM. Given their potent inhibition of viral activity and safety and lack of cytotoxicity, these peptides provide an attractive avenue for the development of new prophylactic and therapeutic agents against SARS-CoV-2.

• Journal of the Korean Dietetic Association
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• v.28 no.4
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• pp.267-280
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• 2022

The purpose of this study was to investigate the consumption status and perception of soy meat among university students and to compare their sensory evaluations of commercial meatballs and soy meatballs. The subjects were students at a university who were grouped into those majoring in food and nutrition and those not majoring in the subject. The results of the two groups were compared. The main sources through which the students became aware of meat analogs were examined. The food and nutrition major students were about three times more likely to learn about meat analogs through 'education', and those not majoring in the subject were about four times more likely to learn about them from the social media (P<0.01). The most common reason for having tried soy meat was 'curiosity' and that for not eating it was 'no opportunity'. Without significant differences between groups, the most common answer for questions relating to the product that they had eaten was 'Ramen flakes' (30.5%) and the most common answer for the routes for eating the product was in the order of: 'restaurants' (36.6%)>school lunches (24.9%)>large and medium-sized supermarkets (22.8%). The most common answer to the question inviting suggestions on 'improvement points to promote the consumption of soy meat' was 'taste'(19.2%), followed by 'product promotion' and 'reasonable price'. About half of the subjects failed to differentiate the soy meatballs from regular meatballs before the sensory test and 21.3% after that. The difference in the sensory test scores of the two types of meatballs with respect to 'texture' was significantly higher for the major students than for the non-major students (P<0.05). These results could provide basic information that could enable the promotion of soy meat.

• Biomolecules & Therapeutics
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• v.5 no.3
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• pp.239-245
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• 1997

Trimetoquinol (TMQ) and its analogs are known to have thromboxane $A_2$ antagonistic action. We also reported that GS389, chemically similar to TMQ, has competitive antagonistic action in rat aorta and human platelets. In the present study, we investigated the pharmacological characteristics of GS283 and GS 386, analogs of GS389, using vascular smooth muscle, human platelets and rat brain homogenates. In isolated pig coronary artery (PCA), both of GS283 and GS386 relaxed U46619-contracted rings in concentration dependent manner. Pretreatment with several concentrations of GS283 and GS386 shifted the dose-response curves to the right, and reduced of maximum contration dose-dependently. Furthermore, GS283 and GS386 strongly inhibited $Ca^{2+}$ -induced contraction in the PCA. In human platelets, U46619- and A23187-induced platelet aggregation was inhibited by GS283 and GS386, concentration-dependently. Anti-platelet aggregation was related to the compound\`s ability to inhibit ATP release at each stimulation. In rat brain homogenates, receptor-binding assay resulted that both GS283 and GS386 have a relative affinity to $\alpha$-adrenergic receptor. Taken together. we concluded that the mechamism of action of GS283 and GS86 is not related with in TXA$_2$ receptor but concerned with calcium antagonistic action and a-blocking action.n.

• Journal of The Korean Association For Science Education
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• v.28 no.4
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• pp.340-349
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• 2008

This study investigated the mapping errors induced in learning the concept of reaction rate with analogies, and compared these mapping errors by the analogy presentation types. Tenth graders (N=418) at a high school were assigned to the four groups by the target concepts and the analogy presentation types. The target concepts were 'concentration and reaction rate' and 'temperature and reaction rate'. In presenting analogy, the verbal and the verbal/pictorial analogs were used. After the students learned one of the analogs, a mapping test was administered. From the analysis, eight types of mapping errors were identified: overmapping, artificial mapping, failure to map, rash mapping, mismapping, mapping of a superficial feature, retention of a base feature, and impossible mapping. According to the analogy presentation types and the features of the target concepts, there were some differences in the frequencies of mapping errors. Educational implications of these findings are discussed.

• Journal of The Korean Association For Science Education
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• v.28 no.5
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• pp.424-437
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• 2008

In this study, we collected teachers' opinions with regard to the effects of the instruction using analogy generation, the disadvantages of the instruction, the problem-solving methods of the instruction, and the teacher's role in it, and accordingly tried to investigate its effectiveness with the analysis of students' academic achievements and motivation, and through the student's interview, after applying the activities of creating generated analogies, finding the difference between the objects and comparisons, and presenting new-known genetics concepts as the students themselves generated analogies. As a result of a teachers' workshop on instruction using analogy development, it was expected to have a positive effect on students' understanding of scientific concepts in genetics, which were found to be difficult for students to understand in learning biology. Students found analogy examples for concepts in genetics in daily life, compared their analogs to those of peers, and examined inconsistencies between targets and analogs through the process of discussion, which finally led to their correct perception of scientific concepts in genetics. In addition, instruction using student-generated analogies proved to have a more positive effect on improving academic achievement and motivating learning, compared with traditional expository instruction.

• Childhood Kidney Diseases
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• v.18 no.2
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• pp.64-70
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• 2014

Purpose: The aims of this study were to assess the clinical and laboratory profiles of chronic kidney disease-mineral bone disorder (CKD-MBD) and to assess the effects of treatment of active vitamin D analogs on severe hyperparathyroidism (SHPT) in pediatric patients on chronic peritoneal dialysis. Methods: This is a retrospective study included 53 patients who had been undergoing dialysis for more than 1 year, between January 2003 and December 2012. Results: Even after treatment with phosphate binders and active vitamin D analogs, the $mean{\pm}standard$ deviation of the percentage of time during peritoneal dialysis that the patients' serum concentrations of phosphorus, corrected total calcium, and parathyroid hormone (PTH) fell within the Kidney Disease Outcomes Quality Initiative recommended ranges was $25.06{\pm}17.47%$, $53.30{\pm}23.03%$, and $11.52{\pm}9.51%$, respectively. Clinical symptoms or radiological signs of CKD-MBD were observed in 10 patients (18.9%). There were significant differences in percentage of time that the serum intact PTH concentration was outside of the recommended range between patients with and without symptoms or signs of CKD-MBD (below recommended range, $11.74{\pm}7.37%$ vs. $40.77{\pm}25.39%$, P <0.001; above the recommended range, $63.79{\pm}27.86%$ vs. $37.09{\pm}27.76%$, P =0.022). Of the 25 patients with SHPT, high-dose alfacalcidol treatment was required in 13 patients that controlled SHPT in 7 of these patients, without marked complications. Conclusion: Despite our efforts to manage CKD-MBD, patients' met the recommended ranges from relevant guidelines at a low frequency. The treatment of high-dose active vitamin D analogs was required in about half of the patients with SHPT and effective in about half of them.