• Journal of Technologic Dentistry
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• v.27 no.1
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• pp.41-55
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• 2005

This study is to investigate the increasing membership rate against the previous year among the members registered as representative members and general members of the Korea Dental Technician Association from 1990 to 2004. With this study, we aim to provide more systematic data about the current status of each members in the KDTA and reconsider the needs for the practical and distinguishing management of the members. Results of the study are as follows; 1. The increasing rate from 1990 to 2004: whole members; 2.14, representative members; 2.22, general members; 2.11. Average of increasing rate against the previous year: general members; 6.10%, whole members; 5.94%, representative members; 5.91%. 2. The increasing rate in the city branch from 1990 to 2004: whole members; 2.12, representative members; 2.03, general members; 2.15. Average of increasing rate against the previous year: general members; 6.63%, whole members; 6.05%, representative members; 5.23%. 3. The increasing rate in the province branch from 1990 to 2004: whole members; 2.21, representative members; 2.74, general members; 2.01. Average of increasing rate against the previous year: representative members; 7.58%, whole members; 5.99%, whole members; 5.35%. 4. Mean ratio between representative members and general members from 1990 to 2004: 1:2.6 against the whole members, 1:2.8 in the city branch, 1:2.3 in the province branch. The ratio between representative members and general members in the year 2004: 1:3.1 in Kyoungnam province, 1:3.0 in Inchon, 1:2.9 in Kwangju that indicates a high ratio between two members and in the case of Chongbuk, the ratio between two members is rather low as shown in 1:1.1.

• Korean Journal of Veterinary Research
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• v.64 no.1
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• pp.3.1-3.8
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• 2024

Canine distemper virus (CDV), canine adenovirus type 2 (CAV-2), canine parvovirus (CPV), and canine parainfluenza virus 5 (CPIV-5) are the major viral pathogens in dogs. Despite the availability of vaccines for dogs against these 4 viral pathogens, investigations of antibodies against these pathogens have rarely been reported in South Korea. In this study, we investigated the recent incidence of viral diseases in dogs and conducted sero-surveillance for CDV, CAV-2, CPV, and CPIV-5 in Korean dogs. The most frequently diagnosed canine viral disease in Korean dog samples from 2000 to 2022 was CPV infection, which accounted for 48.7% (464/953) of the cases. A total of 400 dog serum samples collected between 2019 and 2022 were screened for the presence of virus-neutralizing antibodies against CDV, CAV-2, CPV, and CPIV-5. The overall seropositivity rates for CDV, CAV-2, CPV, and CPIV-5 were 83.8%, 77.8%, 99.3%, and 82.0%, respectively. The protection rate against CPV was the highest (98.3%) and that against CAV-2 was the lowest (44.8%) in dog sera. Male and female dogs showed no significant differences in seropositivity rates. CDV and CPIV-5 seropositivity increased with age in dogs, and the highest incidence and seropositivity rates of CPV indicated that Korean dogs have been continuously exposed to wild CPV, and that CPV is a pathogen that urgently requires attention among canine viral diseases.

• Journal of Environmental Science International
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• v.11 no.1
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• pp.33-40
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• 2002

An antimicrobial substance-producing microorganism was isolated from soil samples. Based of the taxonomic characteristics of its morphological, cultural, physiological properties and 16s rRNA sequence alignment, this microorganism was identified as Pseudomonas aeruginosa, and we named Pseudomonas aeruginosa EL-KM. The optimal culture condition for production of antimicrobial substance was 1% mannitol, 0.4% yeast extract, 0.5% Nacl, 0.2% $K_2SO_4$, 100$\mu$M $MgSO_4$.$7H_2O$, 10$\mu$M $CaCl_2$.$2H_2O$, 1$\mu$M $FeSO_4$.$7H_2O$, 1$\mu$M $MnSO_4$.$4-5H_2O$, initial pH 7 and 200 rpm at 3$0^{\circ}C$. The purification of the antimicrbial substance was performed by silica gel column chromatographys, and fraction with TLC $R_f$ 0.77 value represented good antimicrobial activity. The crude antimicrbial substance was stable within a pH range of 3-10 and temperature range of 4$^{\circ}C$-121$^{\circ}C$ autoclaving. This crude antibacterial substance acted as bacteriolytic agent against Vibrio cholerae non-Ol ATCC 25872, and also exhibited excellent properties, when the substance was demonstrated against many other gram-positive, gram-negative bacteria, yeast and fungi.

• Natural Product Sciences
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• v.19 no.1
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• pp.66-70
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• 2013

Ten compounds (1 - 10), palmitic acid (1), 10-nonacosanol (2), pentacosan-1-ol (3), phytol (4), ${\beta}$-sitosterol (5), ${\beta}$-sitosterol-3-O-${\beta}$-D-glucopyranoside (6), 2,4-dihydroxycinnamic acid (7), hyperoside (8), uridine (9) and adenosine (10), were isolated from the n-hexane and EtOAc-soluble fractions of the aerial parts of A. dioicus var. kamtschaticus (Rosaceae). The structures of these compounds were elucidated on the basis of spectroscopic evidence. All compounds (1 - 10) were isolated for the first time from this plant. Cytotoxicity of 1 - 10 against Jurkat T (T-lymphocytic leukemia cells), HeLa (Human cervical epitheloid carcinoma cells), MCF-7 (Human breast cancer cells), and HL-60 (Human promyelocytic leukemia cells) cell lines was measured. Compound 6 showed good cytotoxicity against HL-60 cell line with $IC_{50}$ value of 8.13 ${\mu}g/mL$. In addition, compounds 7 and 8 exhibited antioxidant activity with $IC_{50}$ values of 16.30 and 12.42 ${\mu}g/mL$, respectively.

• Natural Product Sciences
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• v.5 no.3
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• pp.113-120
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• 1999

Nitric oxide (NO) is a free radical synthesized from L-arginine by nitric oxide synthase (NOS). It is believed that NO is an important mediator in numerous physiological and inflammatory responses. Particularly, a large amount of NO released from the inducible nitric oxide synthase (iNOS) is mostly associated with inflammatory processes. Overproduction of NO in these processes including sepsis and autoimmune diseases can have deleterious consequences and pathophysiologic relevance. Therefore, for the discovery of new inhibitory agents against iNOS activity, we have evaluated about 100 kinds of natural products after partition into three layers (n-hexane, ethyl acetate and aqueous) from 100% methanol extracts to study inhibitory effects on iNOS activity induced by lipopolysaccharide (LPS) in RAW264.7 cells culture system. As a positive control, curcumin, which is known as an anti-tumor promoter, anti-inflammatory agent as an iNOS inhibitor, was used and showed the dose-dependent inhibitory effect $(IC_{50},\;2.5\;{\mu}g/ml)$. Among tested fractions, the n-hexane fraction of Cimicifuga heracleifolia $(IC_{50}:\;9.65\;{\mu}g/ml)$, Forsythiae fructus $(IC_{50}:\;6.36\;{\mu}g/ml)$, Saposhnikovia divaricata $(IC_{50}:\;5.92\;{\mu}g/ml)$, and the ethyl acetate fraction of Chrysanthemum sibiricum $(IC_{50}:\;2.56\;{\mu}g/ml)$, Gastrodia elata $(IC_{50}:\;3.46\;{\mu}g/ml)$, and the aqueous fraction of Dianthus chinensis $(IC_{50}:\;6.73\;{\mu}g/ml)$, Euonymus alatus $(IC_{50}:\;6.78\;{\mu}g/ml)$, Mechania urticifoloria $(IC_{50}:\;8.01\;{\mu}g/ml)$ showed strong inhibitory activity against LPS-stimulated iNOS. Especially, the ethyl acetate fraction of Chrysanthemum sibiricum $(IC_{50}:\;2.56\;{\mu}g/ml)$, which exhibited the strongest inhibition against iNOS, was fractionated with silica-gel column chromatography. These subfractions exhibited dose-dependent inhibition against iNOS activity in the range of $2.59-5.6\;{\mu}g/ml$ except for fraction No. 3, 4, 5, 6, 8, 9, and 16. Our study shows that Chrysanthemum sibiricum has the strongest inhibitory effect against iNOS activity and has similar effect to curcumin. Therefore, further studies for the identification of active principles from Chrysanthemum sibiricum and investigation for the mechanism of the inhibition of iNOS by active principles will be performed.

• Natural Product Sciences
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• v.27 no.1
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• pp.49-53
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• 2021

Balanophora laxiflora Hemsl. (Balanophoraceae) is a traditional medicinal plant with a diverse array of biological activities. In our exploration of new bioactive constituents from B. laxiflora, we isolated five compounds, including a new lignan, balanophorone (5), and four known phenolic compounds (1-4). The chemical structures of these compounds were determined by extensive spectroscopic analyses, including 1D and 2D NMR, HR-ESI-MS, and CD. In addition, we evaluated the effects of each of the isolates (1-5) on the messenger RNA expression levels of tumor necrosis factor (TNF)-α and cyclooxygenase (COX)-2 in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and cytotoxicity against MCF-7 and MDA-MB-231 breast cancer cells. Compound 2 showed significant inhibition of LPS-induced COX-2 and TNF-α expression in RAW 264.7 macrophages, while compound 4 showed moderate cytotoxicity against MCF-7 and MDA-MB-231 breast cancer cells, with IC50 values of 18.3 and 30.7 µM, respectively. No significant effects on the viability of normal mammary epithelial cells were observed.

• The Journal of Advanced Prosthodontics
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• v.11 no.3
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• pp.162-168
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• 2019

PURPOSE. The aim of this study was to evaluate the effect of occlusal adjustments on the surface roughness of yttria-tetragonal zirconia polycrystal (Y-TZP) and wear of opposing artificial enamel. MATERIALS AND METHODS. Twenty-five Y-TZP slabs from each brand (Lava, 3M and Bruxzir, Glidewell Laboratories) with different surface conditions (Control polished - CPZ; Polished/ground - GRZ; Polished/ground/repolished - RPZ; Glazed - GZ; Porcelain-veneered - PVZ; n=5) were abraded (500,000 cycles, 80 N) against artificial enamel (6 mm diameter steatite). Y-TZP roughness (in ${\mu}m$) before and after chewing simulation (CS) and antagonist steatite volume loss (in $mm^3$) were evaluated using a contact surface profilometer. Y-TZP roughness was analyzed by three-way analysis of variance (ANOVA) and steatite wear by two-way ANOVA and Tukey Honest Difference (HSD) (P=.05). RESULTS. There was no effect of Y-TZP brand on surface roughness (P=.216) and steatite loss (P=.064). A significant interaction effect (P<.001) between surface condition and CS on Y-TZP roughness was observed. GZ specimens showed higher roughness after CS (before CS - $3.7{\pm}1.8{\mu}m$; after CS - $13.54{\pm}3.11{\mu}m$), with partial removal of the glaze layer. Indenters abraded against CPZ ($0.09{\pm}0.03mm^3$) were worn more than those abraded against PVZ ($0.02{\pm}0.01mm^3$) and GZ ($0.02{\pm}0.01mm^3$). Higher wear caused by direct abrasion against zirconia was confirmed by SEM. CONCLUSION. Polishing with an intraoral polishing system did not reduce the roughness of zirconia. Wear of the opposing artificial enamel was affected by the material on the surface rather than the finishing technique applied, indicating that polished zirconia is more deleterious to artificial enamel than are glazed and porcelain-veneered restorations.

• Mycobiology
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• v.51 no.4
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• pp.246-255
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• 2023

Genus Penicillium comprising the most important and extensively studied fungi has been well-known as a rich source of secondary metabolites. Our study aimed to analyze and investigate biological activities, including in vitro anti-cancer, anti-inflammatory and anti-diabetic properties, of metabolites from a marine-derived fungus belonging to P. levitum. The chemical compounds in the culture broth of P. levitum strain N33.2 were extracted with ethyl acetate. Followingly, chemical analysis of the extract leaded to the isolation of three ergostane-type steroid components, namely cerevisterol (1), ergosterol peroxide (2), and (3β,5α,22E)-ergosta-6,8(14),22-triene-3,5-diol (3). Among these, (3) was the most potent cytotoxic against human cancer cell lines Hep-G2, A549 and MCF-7 with IC₅₀ values of 2.89, 18.51, and 16.47 ㎍/mL, respectively, while the compound (1) showed no significant effect against tested cancer cells. Anti-inflammatory properties of purified compounds were evaluated based on NO-production in LPS-induced murine RAW264.7 macrophages. As a result, tested compounds performed diverse inhibitory effects on NO production by the macrophages, with the most significant inhibition rate of 81.37±1.35% at 25 ㎍/mL by the compound (2). Interestingly, compounds (2) and (3) exhibited inhibitory activities against pancreatic lipase and α-glucosidase enzymes in vitro assays. Our study brought out new data concerning the chemical properties and biological activities of isolated steroids from a P. levitum fungus.

• Korean Journal of Pharmacognosy
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• v.32 no.3 s.126
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• pp.189-192
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• 2001

Scillascilloside E-3 (1) and E-1 (2) were isolated from the bulbs of Scilla scilloides. The cytotoxic activities of these compounds were tested against murine (B16/F-10, 3LL) and human cancer cell lines (MCF7, PC-3, HT29, LOX-IMVI, A549 and HT1080). These compounds exhibited a significant cytotoxic activities against all tested cancer cells. Futhermore, the contents of 1 and 2 in S. scilloides are 43.2 and 27.9 mg/kg, respectively.

• YAKHAK HOEJI
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• v.49 no.3
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• pp.244-248
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• 2005

From the methanol extract of Rhododendron brachycarpum four triterpenes, three phenylpropanes and a diterpene alkaloid were isolated. Their structures were identified as glutinol (1), 3$\beta$-hydroxyurs-12-ene (2), $\beta$-sitosterol (3), (E)-P-hydrox-ycinnamic acid hexadecylester (4), (-)-rhododendrol (5), (+)-rhododendrol (6), 3$\beta$-hydroxyurs-12-en-28-oic acid (7) and gray-anotoxin I (8) by spectroscopic methods. Compound 8 showed moderate cytotoxicity against five cultured human tumor cell lines with $ED_{50}$ values of $3.21\~4.05 {\mu}g/ml$. The other compounds were of marginal activity against the tested cell lines.