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Matrix metalloproteinase-1 suppression and type-1 procollagen synthesis promoting effects of Uncaria gambir (아선약 추출물의 matrix metalloproteinase-1(MMP-1) 억제 및 제1형 프로콜라겐 합성 촉진 활성)

  • Lee, Jaemin;Kim, Dong-Hee;Kim, Eun-Woo;Kwon, Hyun Ju;Kim, Byung Woo;Cho, Jae-Hyon;Kim, Hyun-Joo;Kim, Tae Hoon
    • Food Science and Preservation
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    • v.24 no.1
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    • pp.93-99
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    • 2017
  • Collagen synthesis is decreased and matrix metalloproteinase-1 (MMP-1) levels are increased in naturally aged human skin, and these alterations cause changes such as skin wrinkling and decreased elasticity. As a part of our ongoing search for bioactive ingredients, MMP-1 inhibitory and type-1 procollagen synthesis inducing activities of aqueous methanolic extract of manufactured gambir product from Uncaria gambir were investigated in in vitro bioassay systems. In addition, total phenolic contents were quantified using a spectrophotometric method. Among tested samples, 40% MeOH eluate from 80% methanolic extract of manufactured U. gambir using open column chromatography packed with Diaion HP-20 resin showed significant MMP-1 inhibitory activities with an $IC_{50}$ value of $15.6{\pm}1.3{\mu}g/mL$. Furthermore, type-1 procollagen synthesis promoting property of 40% MeOH eluate ($IC_{50}$ value; $6.9{\pm}0.7{\mu}g/mL$) from 80% methanolic extract of manufactured gambir was higher than other eluates. Additionally, the present investigation revealed that 40% MeOH eluate of manufactured gambir product contained a high level of total phenolic compounds. The result suggests a distinct relationship between anti-wrinkle activity and total phenolic contents, and manufactured gambir product could be considered a new effective source of natural bioactive ingredients. Systematic investigation of manufactured gambir product will be performed for further development of its biological properties.

The objective and quantitative analysis of malocclusion - Part 2. Influence of malocclusion components to treatment difficulty (부정교합의 객관적 정량분석: Part 2. 부정교합 요소들의 치료난이도에 미치는 영향)

  • Joo, Bo-Hoon;Lee, Ki-Soo
    • The korean journal of orthodontics
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    • v.35 no.1 s.108
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    • pp.69-81
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    • 2005
  • As one of the variations in growth and development of the craniofacial complex. malocclusion shows lack of concordance In the recognition and severity of malocclusion for dentists as well as the acceptance and need of orthodontic treatment for the patient The purposes of this study were 1) to examine the relationships between objective malocclusion severity aid subjective treatment difficulty. 2) to evaluate the effect of malocclusion components to the subjective perceived difficulty of treatment. 3) to establish the weighted values of malocclusion components to reflect the treatment difficulty 100 pairs of dental casts with the general characteristics of malocclusion. were selected from the orthodontic departments of Kyunghee University and Samsuug Medical Center. The severity of malocclusion was evaluated by the author with the PAR index The perceived treatment difficulty and the estimated treatment duration on these dental models were evaluated by 8 experienced orthodontists. The relationships between the objective malocclusion severity and the subjective treatment difficulty were statistically evaluated. and the weighted values of malocclusion components to reflect treatment difficulty were statistically formulated. There were significant relationships between objective malocclusion severity and subjective treatment difficulty The malocclusion components which significantly affected the treatment difficulty and their weighted values in parentheses were as follows upper anterior alignment(1). overbite (2). buccal occlusion (3) middline (4), and overjet (5). This study Provides the fundamental principle to evaluate the objective malocclusion severity which is reflected by the subjective treatment difficulty of Korean orthodontists.

Analysis of the Correlation of Job Satisfaction to Turnover Among Dental Hygienists in the Region of J (J지역 치과위생사의 직무만족과 이직의 상관관계 분석)

  • Ju, On-Ju;Kim, Kyeong-Seon;Lee, Hyun-Ok
    • Journal of dental hygiene science
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    • v.7 no.4
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    • pp.251-256
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    • 2007
  • The purpose of this study was to examine what induced dental hygienists to take up another employment and whether their job satisfaction had anything to do with it in an attempt to help curtail their turnover rate. The subjects in this study were approximately 200 dental hygienists who worked in dental institutions. A survey was conducted from July 24 through September 24, 2006, by using structured, self-administered questionnaires. For data analysis, SPSS 11.5 program was employed to see if their turnover experience was linked to their general characteristics, why they took up another employment, how long they wanted to do that and how their job satisfaction was related to that. The findings of the study were as follows: 1. In regard to turnover experience by age, marital status and career, those who had ever changed their employment accounted for 36.2 percent of the age group from 24 to 26, 83.0 percent of the unmarried ones and 50.0 percent of those whose career was less than one to three years (p < 0.001). By monthly mean income, 50.0 percent of the dental hygienists whose monthly mean income ranged from 1.0 to 1.29 million won had that experience(p < 0.05). The gap between these groups and the others was statistically significant. 2. As for the reason of turnover, working environments were cited most often(28.1%), followed by possibilities(18.0%), relationship with supervisors and colleagues(12.4%), and compensation(4.5%). 3. Concerning a preferred new workplace, 66.2 percent of the dental hygienists who worked in dentist's offices hoped to be newly hired by public dental clinics(p < 0.001). By education, 64.3 percent of the college-educated dental hygienists wanted to work at public dental clinics as well(p < 0.01). 4. The change of employment was under the greatest influence of the possibilities of workplace, followed by workload, pay and relationship with colleagues. All the factors had a negative impact on their turnover. Those who were less satisfied sought new employment more often, and job satisfaction made a statistically significant difference to that. The job satisfaction factors made a prediction of their turnover intention ($R^2=.254$).

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Laparoscopy Application to Determine Estrous Cycle in Korean Black Goats (복강경을 이용한 한국흑염소의 성주기 판정)

  • Yang, H.S.;Jang, S.K.;Yong, H.W.;Cho, J.K.;Shin, S.T.
    • Journal of Embryo Transfer
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    • v.22 no.1
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    • pp.69-74
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    • 2007
  • This study was performed to determine the estrous cycles by macroscopic observation of the ovarian changes using the laparoscopy and to make use of these results for embryo transfer in Korean black goat (Copra hircus aegagrus). Laparoscopic examinations of the ovaries were performed from 2 days after $CIDR^(R)$ removal to 22 days after ovulation. The serial morphological changes of follicles and corpus luteum (CL) were observed. CL was classified corpus hemorrhagicum(CH), corpus luteum (CL) and corpus albicans (CA) by its maturation and regression. On the day before ovulation (Day 0), Graafian follicles (GF) were found on one or both ovaries. On the day (Day 1) and $2^{nd}$day (Day 2) of ovulation, and ovulation depression (OD) and an early stage corpus hemorrhagicum $(CH_1)$ were observed at the site of GF, respectively. On Days 3 to 4, more developed and enlarged corpus hemorrhagicum $(CH_2\;and\;CH_3)$ arised from the ovulation of the GF with well vascularization. On Days 5 to 6, it was identified that mature corpus luteum $(CL_3)$ was grown on the ovary, and fully developed CL with adjacent follicles were occupied most part of the ovary on Days 17 and 18. Then the size of CL was diminished, and completely luteal regression $(CL_1\;or\;CA)$ with new large follicle was identified on Days 20 and 22. From these results, the 4 stages of the estrous cycle in Korean black goats were 1) estrus (Day 0) for 1 day, 2) metestrus $(Day\;1{\sim}4)$ for 4 days (stage of CH development), 3) diestrus $(Day\;5{\sim}16/17)$ for 12 or 13 days (luteal stage), and 4) proestrus $(Day\;17/18{\sim}20/22)$ for 4 or 5 days (stage of luteal regression and follicular growing). Laparoscopy for observation of ovarian changes was invasive than laparotomy. Additionally, it had advantages of reduced adhesion and quick operation time. It was considered that laparoscopic examination of ovarian changes will be useful for embryo transfer in the Korean black goats.

Effects of the Enamel Erosion Caused by Certain Antipyretic and Analgesic Medicines for Children (일부 어린이 해열·진통제의 유치 법랑질 부식효과)

  • Cheun, Su-Kyung;Jeong, Moon-Jin;Ahn, Yong-Soon;Lee, Ye-Jin;Ko, Mi-Kyung;Jeong, Soon-Jeong;Lim, Do-Seon
    • Journal of dental hygiene science
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    • v.16 no.3
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    • pp.235-241
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    • 2016
  • This study was conducted to provide basic understanding regarding possible enamel erosion by three kinds of fist-aid antipyretic and analgesic medicines over a period of time, with comparison and analysis of the resulting deciduous teeth surface and microhardness changes. The analysis was performed using energy dispersive X-ray spectroscopy (EDX) and scanning electron microscope (SEM) to examine the surface erosion and changes. The Kruskal-Wallis test show differences in surface erosion and changes after 3, 5 and 8 days of treatment as well as before and after the treatment in each group. According to the results, there was no significant difference in the early deciduous teeth enamel surface microhardness (p>0.01). However there were signigicant changes after 3, 5, and 8 days (p<0.01). Calcim (Ca) and phosphorous (P) analysis using EDX showed significant differences in the enamel characteristics according to each tissue area after 8 days (p<0.05), but there was no significant difference in any of the areas for P content (p>0.05). In the surface observation with the SEM treatment with Children's Tylenol$^{(R)}$ tablet, which has the lowest pH, looked the roughest, followed by Brufen syrup for children and Children's Tylenol$^{(R)}$ suspension. Based on these results, it should be considered that antipyretic and analgesic medicines for children, which have lower pH values, may cause tooth erosion. Hence, it is necessary to give special attention to oral hygiene in young children or infants by brushing their teeth after such drugs are administered.

A study on the compatibility of implant drivers (임플란트 드라이버의 호환성에 대한 연구)

  • Kim, Min-Soo;Lee, Jong-Hyuk
    • The Journal of Korean Academy of Prosthodontics
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    • v.52 no.1
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    • pp.34-41
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    • 2014
  • Purpose: In this study, the diameter of each implant driver was measured and compared to find out the compatibility of implant drivers. Materials and methods: Drivers from 12 implant systems being used in Dankook University Dental Hospital were included in this study. The shapes of the implant drivers were segregated, and the effective length and the diameter of upper, middle, lower part of driver tips were measured (n=10). The measured data were mathematically analyzed for its compatibility. Results: A driver with the smallest diameter (1.17 mm) had the highest compatibility at the upper part of driver tip. This driver could be used for a bigger driver up to 1.35 mm in diameter. There were several driver groups which had the same diameter so as to be interchangeable each other. In the middle part, the smallest diameter measured was 1.2 mm and this was able to replace a driver up to 1.40 mm diameter. Since the diameter generally became thicker from upper part (the tip of driver) to the lower part (the shank of driver), some drivers with bigger diameter at the upper part so which was failed to show any compatibility became compatible with a driver which had smaller diameter at the upper part but wider in the middle part. The compatibility of torx shape drivers were affected by the inner diameter of the drivers not only by the outer diameter. Furthermore, the inner diameter of torx drivers decided the compatibility between torx and hex drivers. Conclusion: From the study it was found that compatibility in drivers existed among certain implant systems and to check its compatibility the diameter at a certain effective length should be measured. However, there has been not enough studies about long-term use of compatible drivers, so effects of using compatible drivers on drivers and implants are unknown. Therefore, usage in inevitable cases only is recommended and further study is needed.

Proteinases and their Inhibitors in Cartilage and Synovial Fluid Acquired from a Canine Osteoarthritic Model (개 퇴행성 관절염 모델을 이용한 연골과 활액 내 단백질 분해 효소와 억제제의 작용 연구)

  • Seo, Jae-Won;Lee, Hae-Beom;Kim, Nam-Soo;Lee, Young-Hoon;Kang, Hyung-Sub;Kim, In-Shik;Park, Sang-Youel
    • Journal of Veterinary Clinics
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    • v.26 no.2
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    • pp.144-149
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    • 2009
  • Chondrocytes and synovial fluid derived markers are used to monitor for osteoarthritis(OA). Specific inhibitors, known as tissue inhibitors of metalloproteinases(TIMP), regulate the proteolytic activity of matrix metalloproteinases(MMP). This study investigated whether MMP and TIMP levels were altered in synovial fluid and cartilage following the experimental induction of OA in canines. Twenty mature beagle dogs underwent a unilateral surgical transection of the cranial cruciate ligament and the medial collateral ligament as well as a medial meniscectomy. Matrix metalloproteinase-2 and MMP-9 levels were assayed using Western blot and TIMP-2 levels were measured with enzyme-linked immunosorbent assays four weeks after OA induction. Increased MMP-2 expression was observed in chondrocytes isolated from cartilage following OA induction, but MMP-9 expression decreased. Matrix metalloproteinase-2 and MMP-9 levels in synovial fluid from the OA induced joint significantly increased compared to those of the sham group. Tissue inhibitors of metalloproteinase-2 concentrations were higher in chondrocytes from the OA cartilage, yet TIMP-2 remained lower in the synovial fluid of OA. This suggests the elevated release of MMP-9 over MMP-2 into the synovial fluid following the cartilage degradation-related death of chondrocytes after OA. Osteoarthritis can be further deteriorated by increased MMP activity in the synovial fluid because TIMP-2 exist low concentration into the extracellular matrix. As a result, MMP activity, particularly MMP-9 activity, can be useful as a biomarker in diagnosing and monitoring the early stages of canine OA.

Relationship among Job Characteristics, Jod Satisfaction and Organizational Commitment of Dental Technicians (치과기공소 근무자의 직무관련 요인과 직무만족 및 조직몰입과의 상관관계)

  • Han, Chang-Sik
    • Journal of Technologic Dentistry
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    • v.10 no.1
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    • pp.89-111
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    • 1988
  • This study relates to the procedures and the attitude of dental technicians. In order to identify the attitude factors which have influence on the job satisfaction and the organizational commitment, self-administered questionnares were distributed by mail to 504 technicians randomlyselected from 482 dental laboratories registered in Korean Dental Lab. Association from February 6 to February 27, 1987. The following results were obtained: 1. Canonical correlation between the group of general variables and the group of job satisfactional variables was significant statistically as Rc=0.48. But canonical correlation between the group of general variables and the group of organizational commitment variables was insignificant statistically as Rc=0.37. 2. Canonical correlation between the group of job characteristic variables and the group of job satisfactional variables was highly significant statistically as Rc=0.69. Wage propriety, promotion opportunity and benefits propriety were highly influential factors among the job characteristic variables. 3. Canonical correlation between the group of job characteristic variables and the group of organizational commitment variables was highly significant statistically as Rc=0.61. Wage propriety, promotion opportunity of acquiring technique and duty importance were highly influential factors among the job characteristic variables. 4. The job characteristic variables which had influence on the job satisfaction varied statistically according to the general variables. in case of age, technical career, academic career and duty, the job characteristic variable was wage propriety and the business relations. 5. The job characteristic variables which had influence on the organizational commitment varied statistically according to the general variables. The case of male was applicable to wage propriety, the case of female was applicable to benefits propriety, the case of dental technicians who were less than 30 years old was applicable to wage propriety, the case of dental technicians who had more than 5 years technical career was applicable to monotonousness. 6. The most influential factor was wage propriety among job characteristic variables which influenced on the job satisfaction and the organizational commitment of dental technicians.

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The objective and quantitative analysis of malocclusion : Part 1. Objective malocclusion severity and subjective treatment difficulty (부정교합의 객관적 정량분석: Part 1. 객관적 부정교합 경중도와 주관적인 치료난이도의 상관관계)

  • Joo, Bo-Hoon;Lee, Ki-Soo
    • The korean journal of orthodontics
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    • v.35 no.1 s.108
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    • pp.60-68
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    • 2005
  • The evaluation of malocclusion has to be done quantitatively and qualitatively. This will be lead toward an analysis of malocclusion severity as well as treatment difficulty. The method of proper evaluation of malocclusion severity and treatment difficulty is necessary to assess treatment effect and efficiency for the orthodontists and to establish fundamentals for planning and executing the health-related policies in private and public institutions. The purposes of this study as the first part of the objective and quantitative analysis of malocclusion were 1) to measure treatment difficulty based on the opinions of several orthodontists. and 2) to investigate the relationships between objective malocclusion severity and subjective treatment difficulty 100 pairs of dental casts that had various types and severity of malocclusion were selected from the orthodontic departments of Kyurghee University and Samsung Medical Center The objective malocclusion severity was measured with the PAR (Peer Assessment Rating) index and the subjective treatment difficulty was evaluated by 8 experienced orthodontists. The relationships between objective malocclusion severity and subjective treatment difficulty were statistically evaluated. There were significant relationships between objective malocclusion severity and subjective treatment difficulty especially in the measurements of the upper anterior alignment, the buccal occlusion. the overjet, the overbite and the midline discrepancy en the malocclusion components. The results of this study can provide the background knowledge to develop a new occlusal index. which contains both the malocclusion severity and treatment difficulty for Korean orthodontists.

Licochalcone C Induces Autophagy in Gefitinib-sensitive or-resistant Human Non-small Cell Lung Cancer Cells (Gefitinib-민감성 또는 내성 비소세포폐암 세포에서 Licochalcone C에 의한 자가포식 유도)

  • Oh, Ha-Na;Yoon, Goo;Chae, Jung-Il;Shim, Jung-Hyun
    • Journal of Life Science
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    • v.29 no.12
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    • pp.1305-1313
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    • 2019
  • Licochalcone (LC), isolated from the roots of Glycyrrhiza inflata has multiple pharmacological effects including anti-inflammatory and anti-tumor activities. To date, Licochalcone C (LCC) has induced apoptosis and inhibited cell proliferation in oral and bladder cancer cells, but lung cancer has not yet been studied. In addition, no study reported LCC-induced autophagy in cancer until now. The present study was designed to investigate the effect of LCC on gefitinib-sensitive and -resistant lung cancer cells and elucidate the mechanism of its action. The 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay data showed that LCC significantly inhibited cell viability in non-small cell lung cancer (NSCLC) HCC827 (gefitinib-sensitive) and HCC827GR (gefitinib-resistant) cell lines. Interestingly, Annexin V/7-aminoactinomycin D double staining and cell cycle analysis showed an apoptosis rate within about 20% at the highest concentration of LCC. LCC induced G2/M arrest by reducing the expression of the cell cycle G2/M related proteins cyclin B1 and cdc2 in NSCLC cell lines. Treatment of LCC also induced autophagy by increasing the expression of the autophagy marker protein microtubule-associated protein 1 light chain 3 (LC3) and the protein autophagy-related gene 5 involved in the autophagy process. In addition, LCC increased the production of reactive oxygen species (ROS), and the cell viability was partially restored by treatment with the ROS inhibitor N-acetyl-L-cysteine. In western blotting analysis, the expression of cdc2 was increased and LC3 was decreased by the simultaneous treatment of NAC and LCC. These results indicate that LCC may contribute to anti-tumor effects by inducing ROS-dependent G2/M arrest and autophagy in NSCLC. In conclusion, LCC treatment may be useful as a potential therapeutic agent against NSCLC.