크롬(Ⅵ)의 체내 흡수와 소실속도에 관한 연구

김현영,이성배,임철홍,이권섭,정용현,이종성,한정희,전윤석,황호순,이용묵 한국산업위생학회 2003 한국산업보건학회지 Vol.13 No.1

The CrO3 mostly used in plating. metal surface disposal, leather, cosmetic manufacturing, as an experiment material by repeatedly inhaling and exposure the male S.D. rats at a 0.00, 0.2., 0.50, 1.25 mg/㎡ concentration(particle size: 0.5-0.5 aerosol)6hours a day, 5day a week in 13weeks comparing with 2weeks, 8weeks of recovery group about the noxiousness of the experiment animal and the reduce scale of the CrO3 in the internal organ especially in blook and respiratory organ with the period of convalescent and clearance. The experiment results which we received are as follows. 1. In blood the RBC, HGB and HCT experiment, rats with 0.20, 0.50 mg/㎡ concentration showed that there were some decreases but not dependent. The kidneys absolute weight compared with control group was reduced intentionally(p〈0.05) and the lungs absolute weight compared with control group showed intentional increase(p〉0.05). 2. After the exposure of the experiment material, the whole blook, l\blood plasma and red blood cell in blood by (x): the period of convalescent, per (y); the decreasing of Cr concentration, was y=66.51 e -0.057x, y=67.2 e-0.101x, y=70.01 e-0.030 in 0.50 mg/㎡ exposure concentration by calculating the clearance coefficient of correlation, and the half life (day)was estimated 12.0, 6086, 23.0 each. 3, After the exposure of the experiment material, the experiment animals lung, liver and kidneys by(x); the period of convalescent, per (y); the decreasing of Cr conentration, was y=1808 e-0.00493x, y=12.02e-0.0297x, y=67.61 e-0.0292x in 0.50mg/㎡ exposure concentration by calculating the clearance coefficient of correlation, and the half life(day)was estimated 140.6, 23.3, 23.7, each, and including lung, liver with all of the experiment internal organs, the Cr clearance decreased as the exposure concentration increased.

Microseal??을 이용한 근관충전법의 근관폐쇄능력 평가

유현미,오태석,황혜경 大韓齒科保存學會 1998 Restorative Dentistry & Endodontics Vol.23 No.2

전기도금을 이용한 스테인레스 스틸 각형 선재의 굵기 증가 후 물성 변화

이정석,이기헌,황현식 대한치과교정학회 2003 대한치과교정학회지 Vol.33 No.2

본 연구는 전기도금을 이용하여 각형 선재의 굵기를 증가시킨 후 기존의 선재와 물성을 비교함으로서 이의 임상적 적용 가능성을 알아보고자 시행되었다. 한 변의 길이가 0.016 인치인 정사각형 스테인레스 스틸 교정용 선재에 니켈 전기도금을 시행하여 굵기를 0.01 인치 증가시켜 한 변의 길이가 0.017 인치인 정사각형 선재로 만들었고 도금층의 밀착성을 증진시키기 위해 400℃의 전기로 에서 10분간 열처리를 시행하였다. 시편의 물성변화를 알아보기 위하여 전기도금을 이용하여 제작된 15개의 시편을 실험군(016P군)으로, 기존의 0.016인치(016), 0.017 인치(017군) 스테인레스 스틸 교정용 선재를 대조군으로 설정한 후 3점 굴곡 시험과 비틀림 시험을 시행하여 다음과 같은 결과를 얻었다. 1. 3점 굴곡 시험 결과 016P군에 비해 강성과 항복강도, 국한강도 모두 증가하는 경향을 보였으며, 강성과 극한강도는 통계적으로 유의한 차이가 있었다(p<0.05). 2. 3점 굴곡 시험 결과016P군이 017보다 강성과 항복강도, 극한강도 모두 낮은 경향을 보였으며, 강성은 통계적으로 유의한 차이가 있었다(p<0.05). 3. 비틀림 시험 결과 016P군이 016군에 비해 비틀림 모멘트, 최대 비틀림 모멘트 모두 높았으며, 통계적으로 유의한 차이가 있었다(p<0.05). 4. 비틀림 시험 결과 016P군이 017군에 비해 비틀림 강성과 항복 비틀림 모멘트, 최대 비틀림 모멘트 모두 낮은 경향을 보였으며, 이 중 항복 비틀림 모멘트와 최대 비틀림 모멘트에서 통계적으로 유의한 차이가 있었다(p<0.05). 이상의 결과를 요약해 보면 각형 선재에 도금을 시행하여 굵기를 증가시키고 물성이 증가될 수 있음을 알았다. 비록 도금을 시행한 016P군이 기존의 017군보다 강성이 낮았으나 이는 반대로 016P군이 017군보다 탄성이 높음을 나타내며 토크조절이 부족한 경우 브라켓 슬롯에 쉽게 삽입되어 교정력을 발휘할 것으로 기대된다. The purpose of this study was to evaluate clinical applications of electroplating method through investigation of the physical properties of orthodontic rectangular wires according to varying their cross section. For the study, it was accomplished to electroplate the 0.016-inched orthodontic rectangular stainless steel wire. The cross section of stainless steel orthodontic rectangular wire increased from 0.016 x 0.016 inch to 0.017 x 0.017 inch by electroplating. The wire was heat treated to improve an adhesion between the wire and electroplated metal. A three=point bending test and torsion test were conducted in order to compare physical properties among three wire groups; 0.016 X 0.016 wires (group 016), electroplated 0.016 x 0.016 wires (group 016P) and 0.017 x 0.017 wires (group 017). Through the investigation of each wire group, following results were obtained. 1. At three-point bending test, the group 016P showed higher tendency in the degree of stiffness, yield strength and ultimate tensile strength than the group 016. Stiffness and ultimate tensile strength showed statistically significant differences between two groups at three-point bending test (p<0.05). 2. Stiffness, yield strength, and ultimate tensile strength of the group 016P showed lower tendency than those of the group 017. Stiffness showed statistically significant differenced between two groups at three-point bending test (p<0.05). 3. Torque/twist rate, yield torsional moment, and ultimate torsional moment of the group 016P showed higher tendency than those of the group 016. All measurements showed statistically significant differences between two groups after torsion test (p<0.05). 4. Torque/twist rate, yield torsional moment, and ultimate torsional moment of the group 016P showed lower tendency than those of the group 017. Yield torsional moment, and ultimate torsional moment showed statistically significant differences between two groups after torsion test(p<0.05)

교정치료 시 브라켓 부착 및 제거에 따른 치아색 변화

김석필,황인남,조진형,황현식 대한치과교정학회 2006 대한치과교정학회지 Vol.36 No.2

본 연구는 교정용 브라켓 부착을 위한 레진 접착부위 및 그 인접부위 즉, primer만 도포된 부위의 색변화를 알아보기 위하여 시행되었다. 교정치료를 위해 발치된 60개의 건전한 소구치를 재료로 사용하여 분광측정기로 색을 측정한 후 CIE L*a*b* 색표계로 기록하였다. 20개의 소구치에 광중합형 접착레진으로 브라켓을 부착한 후 부착 전과 제거 후의 색을 측정하였으며 다른 20개의 소구치에는 primer만 도포하고 도포 전과 도포 후의 색을 측정한 후, L* 값을 이용하여 명암 변화를 살펴본 결과 브라켓 부착 및 primer 도포 모두의 경우 명도가 감소하는 경향을 보였으며, a* 값과 b* 값을 이용하여 색상 변화를 살펴본 결과 황색이 증가하는 양상을 나타내었다. 또한 측정된 L*a*b* 값을 이용하여 색변화를 산출하고 임상적으로 인지할 수 있는 색변화 값 3.7을 기준치로 하여 비교 및 분석을 시행한 결과 브라켓 부착 전과 제거 후의 색변화는 기준치보다 큰 것으로 나타났으며 primer 도포에 따른 색변화는 기준치보다 크지 않은 것으로 나타났다. 한편 primer만 도포한 경우 칫솔질에 따른 색변화를 알아보고자 나머지 20개의 소구치를 대조로 하여 칫솔질을 시행한 결과 칫솔질 시행 후 색변화는 기준치보다 큰 것으로 나타났다. 브라켓 제거 후 자연광 노출의 영향을 알아보기 위하여 모든 경우에 추가적으로 photoaging을 시행한 결과 부기적인 색변화는 기준치보다 작은 것으로 나타났다. 이상의 결과는 교정치료를 위한 브라켓 부착으로 인해 브라켓 부착 및 인접부위의 치아색 변화가 있음을 의미하며 임상과정에서 이에 대한 고려가 필요함을 시사하였다. The purpose of this study was to evaluate the tooth color changes of resin bonding sites and their adjacent sites on orthodontic bracket bonding. Sixty extracted sound premolars were used and the tooth color was recorded according to the CIE L*a*b* color system using a spectrophotometer. The tooth colors of the twenty premolars were measured and compared before bracket bonding and after removal. On a further twenty premolars, the tooth color was measured before and after only primer application. In the change of L* values, according to the bracket bonding and primer application, the lightness was decreased, and in the change of a* and b* values, the color was changed into a more yellowish color. The color differences (ΔE*) were calculated from the L*a*b* values and compared with the standard value of clinical detection (ΔE*=3.7). The color differences between before the bracket bonding and after removal noted exceeded the standard value and those of between before and after the primer application were not larger than the standard value. Tooth brushing was performed after application of the primer to evaluate the color changes according to the primer abrasion. As a control, toothbrushing was performed on the last twenty premolars. The color differences noted were larger than the standard value after toothbrushing. Also, to evaluate the color changes of the tooth which is exposed to sun irradiation after bracket removal, additional photoaging was performed and the color was measured for all teeth. The additional color differences after photoaging were smaller than the standard value. The above results suggest that the tooth color changes after fixed orthodontic treatment.

폴리카보네이트 브라켓 부착 시 결합강도 증진을 위한 표면처리 효과

김석필,김년경,이현정,황현식 대한치과교정학회 2006 대한치과교정학회지 Vol.36 No.5

본 연구는 폴리카보네이트 브라켓 부착 시 표면처리가 결합강도를 증진시키는지 알아보고자 시행되었다. 소의 하악 중절치를 포매하여 만든 100개의 시편에 광중합형 레진 접착제를 이용하여 폴리카보네이트 브라켓(Alice, 광명 데이콤, 대한민국)을 부착하였다. 대조군의 경우, 표면처리 없이 부착한 반면, 실험군의 경우 샌드블라스팅 처리한 경우, plastic conditioner 처리하여 부착한 경우, 그리고 샌드블라스팅과 함께 plastic conditioner 처리한 경우로 구분하여 접착하였다. 만능시험기를 이용하여 전단결합강도를 측정하고 파절양상을 비교 분석한 결과, plastic conditioner나 샌드블라스팅으로 표면처리를 시행한 경우 표면처리를 시행하지 않은 경우에 비해 높은 결합강도를 보였다 (p<0.001). 샌드블라스팅과 Plastic conditioner를 모두 처리한 경우는 샌드블라스팅만이나 plastic conditioner만 처리한 경우보다 높은 결합강도를 보였으며, 특히 샌드블라스팅만 처리한 경우에 비해서는 통계적 유의차를 보였다 (p<0.05). 이상의 연구결과는 폴리카보네이트 브라켓 부착 시 결합강도 증진을 위해서 베이스의 표면처리가 필요하며 샌드블라스팅 후 plastic conditioner 도포가 가장 효과적임을 보여주었다. Objective: The purpose of this study was to evaluate whether the bond strength of polycarbonate brackets can be increased through surface treatment. Methods: One hundred polycarbonate brackets (Alice) were bonded to bovine incisors with light-cured adhesive. The bracket bases were treated with one of three methods; sandblasting, plastic conditioner application, and combined treatment with sandblasting and plastic conditioner. The brackets without any surface treatment served as the control. The shear bond strength was tested with a universal testing machine, and failure pattern was assessed with the adhesive remnant index. Results: The shear bond strength in all experimental groups was higher than that of the control group (p<0.001). The group treated with plastic conditioner after sandblasting showed statistically higher shear bond strength than the sandblasting only group (p<0.05). The group treated with plastic conditioner after sandblasting showed higher shear bond strength than plastic conditioner only group, but the difference was not statistically significant. Conclusion: The above results suggest that the surface treatments of polycarbonate bracket is mandatory to improve bond strength, and the most effective method is an application of plastic conditioner after sandblasting.

전기도금을 이용한 스테인레스스틸 각형 선재의 굵기 증가 후 물성 변화

이정석,황현식,최광철,문재동 전남대학교 치의학연구소 2002 구강과학 Vol.14 No.1

The purpose of this study was to evaluate clinical applications of electroplating method through investigation of the physical properties of orthodontic rectangular wires according to varying their cross section. For the study, it was accomplished to electroplate the 0.016-inched orthodontic rectangular stainless steel wire. The cross section of stainless steel orthodontic rectangular wire increased from 0.016 X 0.016 inch to 0.017 X 0.017 inch by electroplating. The wire was heat treated to improve an adhesion between the wire and electroplated metal. A three-point bending test and torsion test were conduced in order to compare physical properties among three wire groups; 0.016 X 0.016 wires(group 016P) and 0.017 X 0.017 wires(group 017). Through the investigations of each wire group, following results were obtained. 1. At three-point bending test, the group 016P showed higher tendency in the degree of stiffness, yield strength and ultimate tensile strength than the group 016. Stiffness and ultimate tensile strength showed statistically significant differences between two groups at three-point bending test(p<0.05). 2. Stiffness, yield strength, and ultimate tensile strength of the group 016P showed lower tendency than those of the group 017. Stiffness showed statistically significant differences between two groups at three-point bending test(p<0.05). 3. Torque/twist rate, yield torsional moment, and ultimate torsional moment of the group 016P showed higher tendency than those of the group 016. All measurements showed statistically significant differences between two groups after torsion test(p<0.05). 4. Torque/twist rate, yield torsional moment, and ultimate torsional moment of the group 016P showed lower tendency than those of the group 017. Yield torsional moment, and ultimate torsional moment showed statistically significant differences between two groups after torsion test(p<0.05). Xylitol is a 5-carbons carbohydrate, which can be replaced with sucrose for preventing caries. The replication of Streptococcus mutans and its formation of artificial plaque were studied in the media containing xylitol. The combined effect of xylitol and other carbohydrates on Streptococcus mutans was also studied. The replication of Streptococcus mutans was inhibited according to the increased concentration of xylitol. Streptococcus mutans replicated at the initial stage of incubation in the media contaning glucose, fructose or lactose, while replication from the beginning of incubation in the media containing fructose as combining with xylitol. The formation of artificial plaque by Streptococcus mutans was significantly reduced in the media containing with xylitol and fructose. These results indicated that the replication of Streptococcus mutans was inhibited according to the increased concentration of xylitol, and the formation of artificial plaque by Streptococcus mutans was significantly inhibited in the media containing xylitol and fructose.

The effect of combined Rehmannia glutinosa Libosch and Eleutherococcus senticosus Max(OPB) extracts on bone mineral density in ovariectomized rats.

Kim,Jung-Keun 대한구강생물학회 2007 International Journal of Oral Biology Vol.32 No.4

This study was conducted to investigate the preventingeffects of OPB (Rehmannia glutinosa Libosch and Eleuth-erococcus senticosus Max extracts) and combined OPB/Calcium therapy on bone loss in ovariectomized rats. SixtySprague Dawley rats of 12-week-old were divided into eightgroups: OVX (ovariectomized), OPBL (OPB 50mg/kg),OPBM (OPB100mg/kg), OPBH (OPB 200mg/kg), OPBL/CAL(OPBL+CAL), OPBM/CAL (OPBM+CAL), OPBH/CAL (OPBH+CAL) and CAL (Calcium citrate 88.33mg/kg+1α, 25-dihydroxy-vitamin D3 33.33IU/kg). Bone mineraldensity (BMD), bone mineral content (BMC), bone strengthindices and cortical thickness were analyzed by peripheralquantitative computerized tomography (pQCT). pQCTscanning showed that OVX induced a significant decreasein trabecular bone mineral density and bone mineralcontent in the proximal tibia (-36.4±2.4%, -21.8±12.7%).These decreases were significantly prevented by theadministration of OPBM and OPBM/CAL. Cortical BMDand BMC of tibia were slightly enhanced by OPB and OPB/CAL. However there was no significant difference betweenOVX and OPB, OPB/CAL treated group. Bone strengthindices and cortical thickness were not significantly different.Our results suggest that OPB and combined OPB/Calciumtherapy are effective in preventing the development of boneloss induced by ovariectomy in rats.

서울의 Penicillinase Producing Neisseria gonorrhoeae 발생빈도(1997)

김재홍,문득곤,김정수,김용준,임동진,박상훈,김희성,이민수,송기훈,김갑형,김형석,성소영,이인섭,김석우,황지환,조창근,김경문,부태성 대한화학요법학회 2000 대한화학요법학회지 Vol.18 No.3

Background : In recent years, gonorrhea has been pandemic and remains one of the most common STDs in the world, especially in developing countries. Objective & Methods : For the detection of a more effective therapeutic regimen and assessing the prevalence of PPNG, we have been trying to study the patients who have visited the Venereal Disease Clinic of Choong-Ku Public Health Center in Seoul since 1980 by means of the chromogenic cephalosporin method. Results : In 1997. 99 strains of N. gonorrhoeae were isolated, among which 45(45.5%) were PPNG. Conclusion : The prevalence of PPNG in Seoul, which had been decreased to 39% in 1996 after a peak of 74.3% in 1993, is increased to 45.5% in 1997.

Improved Gastrointestinal Symptoms and Quality of Life after Conversion from Mycophenolate Mofetil to Enteric-Coated Mycophenolate Sodium in Renal Transplant Patients Receiving Tacrolimus

Hwang, Hyeon Seok,Hyoung, Bok Jin,Kim, Sol,Oh, Ha Young,Kim, Yon Su,Kim, Jung Kyung,Kim, Yeong Hoon,Kim, Yong Lim,Kim, Chan Duck,Shin, Gyu Tae,Yang, Chul Woo The Korean Academy of Medical Sciences 2010 JOURNAL OF KOREAN MEDICAL SCIENCE Vol.25 No.12

<P>It is reported that a conversion from mycophenolate mofetil (MMF) to enteric-coated mycophenolate sodium (EC-MPS) relieves gastrointestinal (GI) symptom burden and improves health-related quality of life (HRQoL). However, it is unclear whether renal transplant recipients using tacrolimus receive the same benefit from the conversion. In this prospective, multi-center, open-label trial, patients were categorized into two groups by their GI symptom screening. Equimolar EC-MPS (n=175) was prescribed for patients with GI burdens; those with no complaints remained on MMF (n=83). Gastrointestinal Symptom Rating Scale (GSRS) and Gastrointestinal Quality of Life Index (GIQLI) were evaluated at baseline and after one month. Patients and physicians completed Overall Treatment Effect (OTE) at one month. EC-MPS-converted patients had worse GSRS and GIQLI scores at baseline than MMF-continued patients (all <I>P</I><0.001). Significant improvements in GSRS and GIQLI scores were observed for EC-MPS-converted patients at one month, but MMF-continued patients showed worsened GSRS scores (all <I>P</I><0.05). OTE scale indicated that EC-MPS patients improved in overall GI symptoms and HRQoL more than MMF patients did (<I>P</I><0.001). In tacrolimus-treated renal transplant recipients with GI burdens, a conversion from MMF to EC-MPS improves GI-related symptoms and HRQoL.</P>

Poster Session:PS 0497 ; Nephrology : Paricalcitol Pretreatment Attenuates Apoptosis and Infl ammation in Renal Ischemia-Reperfusion Injury via Prostaglandin E2 Receptor Ep4

( Hyeon Seok Hwang ),( Keum Jin Yang ),( Sung Eun Kim ),( Ki Cheol Park ),( Hyun Soo Choi ),( Jeong Min Oh ),( Yoon Kyung Chang ),( Cheol Whee Park ),( Chul Woo Yang ),( Suk Young Kim ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

Background: Paricalcitol has protective effects against renal ischemia-reperfusion (IR) injury, but the mechanism by which this occurs remains unclear. We investigated whether paricalcitol attenuates apoptosis and infi ammation in renal IR injury through the prostaglandin E2 (PGE2) receptor EP4. Methods: Human proximal tubular cell line (HK-2) was exposed to LPS and ischemia by mineral oil monolayer. Male C57BL/6 mice were subjected to 23 min of bilateral kidney ischemia and 24 h reperfusion. The effects paricalcitol pretreatment with or without antagonist was investigated in both in vitro and in vivo models. Results: Paricalcitol treatment upregulated the signaling pathway of cyclooxygenase (COX)-2 and PGE2, and it increased the expression of EP4 in HK-2 cells. Paricalcitol pretreatment prevented the HK-2 cell death induced by IR and LPS exposure, and the cotreatment of EP4-specifi c antagonist offset the cell protective effects of paricalcitol. The phosphorylation of Akt and cAMP-responsive element binding protein was increased after paricalcitol pretreatment in IR-exposed cells. EP4 antagonist blunted the phosphorylation of these cell survival signals. EP4 antagonist also reversed the inhibitory effects of paricalcitol on p65 NF-κB phosphorylation and nuclear translocation in LPS-exposed cell. In mice kidneys with IR injury, EP4 blockade restored serum creatinine levels and tubular necrosis, which was reduced by paricalcitol pretreatment. Decreased TUNEL-positive cells, decreased Bax levels and increased Bcl-2 expression were observed in paricalcitol-treated mice kidney with IR injury. These apoptotic effects of paricalcitol were abolished by EP4 antagonist. Paricalcitol attenuated the infiltration of infiammatory cells (T-cells and macrophages) and the production of proinfi ammatory cytokines (RANTES, tumor necrosis factor-a, interleukin-1ß and interferon- γ, MIP-1a). The cotreatment with EP4 antagonist reversed the infi ammatory cells infi ltration and proinfi ammatory cytokines expressions. Conclusions: Paricalcitol attenuates apoptosis and infi ammation through the EP4 dependent pathway in renal IR injury.