• 대한소아치과학회지
• /
• 제43권4호
• /
• pp.461-466
• /
• 2016

치아 우식증은 어린이와 청소년에서 일생에 거쳐 지속되는 질병이며 가장 중요한 치과질환이다. 유치열기의 치아우식증은 영구치에도 영향을 미치기 때문에 유치의 치아우식증을 조기에 진단하는 것은 매우 중요하다. 또한 예방을 하는 것이 매우 중요한데 치아 우식증을 조기에 발견하여 우식 위험율이 높은 아이들에서 적극적으로 불소 도포, 치면 열구 전색 등을 미리해주는 것이 중요하다. 치아우식증을 조기에 발견하기 위한 방법들이 많이 개발되어 왔지만 더 효율적인 방법을 찾기 위해 여전히 많은 연구가 진행 중이다. 일반적으로 시진과 방사선 사진을 많이 사용해왔지만 시진의 부정확성과 방사선의 조사량 등 많은 한계점을 보이고 있다. 이번 연구에서는 치아 우식증에 있어서 새로 개발된 DIAGNOcam의 임상적 적용에 대해 알아보고 그 활용 가능성을 알아보고자 하였다. 소아치과에 내원한 환자들을 대상으로 구치부에 DIAGNOcam을 이용하여 진단한 결과 인접면 우식, 수복물의 변연 확인 및 우식의 범위 확인에 유용하게 사용될 수 있다는 점을 확인하였다.

• Journal of Chest Surgery
• /
• 제21권5호
• /
• pp.803-815
• /
• 1988

The present experiments were performed to confirm the hypothesis that xanthine oxidase[XOD], as a source and mechanism of oxygen radical production, plays an important role in the genesis of the reperfusion injury of ischemic myocardium. The experimental ischemic-reperfusion injury was induced in isolated, Langendorff preparations of rat hearts by 60 min. Of global ischemia with aortic clamping followed by 20 min. of reperfusion with oxygenated Krebs-Henseleit solution[pH 7.4, 37*C]. The results were as follows: 1. The releases of creatine phosphokinase and a lipid peroxidation product, malondialdehyde[MDA] into the coronary effluent were abruptly increased upon reperfusion of ischemic hearts. The increases of the enzyme and MDA were suppressed significantly in the hearts removed from rats pretreated with allopurinol, a specific XOD inhibitor[20mg/kg, oral, 24 hrs and 2 hrs before study]. This effect of allopurinol was comparable to that of oxygen radical scavengers, superoxide dismutase[5, 000U] and catalase[12, 500 U]. 2. The increased SOD-inhibitable reduction of ferricytochrome C, which was infused to the hearts starting with reperfusion, was significantly suppressed in allopurinol pretreated hearts. 3. Activities of myocardial XOD were compared in the normal control hearts and the ischemic ones. Total enzyme activities were not different in both hearts. However, comparing with the control, the ischemic ones showed higher activity in 0-form and lower activities in D-form and D/O-form. 4. In the ischemic hearts, phenylmethylsulfonyl fluoride, a serine protease inhibitor, prevented significantly the increase of 0-form and the decreases of D and D/O-form, while thiol reagents did not affect the changes of the enzyme. 5. The increase of 0-form and the decreases of D and D/0-form were not significant in both calcium-free perfused and pimozide, a calmodulin inhibitor, treated ischemic hearts. 6. The SOD-inhibitable reduction of ferricytochrome C were suppressed by PMSF and pimozide treatment as well as by calcium-free perfusion. It is suggested from these results that in the ischemic rat myocardium, xanthine oxidase is converted to oxygen radical producing 0-form by calcium, calmodulin-dependent proteolysis and plays a contributing role in the genesis of ischemic-reperfusion injury by producing oxygen free radicals.

• 치위생과학회지
• /
• 제17권3호
• /
• pp.202-208
• /
• 2017

Korea has been running the community oral health program for the elderly, including topical fluoride application and scaling. The aim of this study was to compare the subjective and objective oral health status of 345 participants according to the number of participants in the program and of 37 participants before and after the 5-year program. The survey consisted of an interview questionnaire and oral examinations. Analysis of variance was used to compare the variables of the 345 participants according to the numbers of participants. Paired t-test was used to compare the oral health statuses before and after the 5-year program in 37 subjects. There was no difference in subjective oral health status according to the number of participants in the oral health program in the elderly, including subjective health status, subjective oral health status, satisfaction with oral health, concern about oral health, need of dental treatment, oral pain, tooth sensitivity, subjective periodontal health, and subjective symptoms of periodontitis. The community periodontal index (CPI) of the 1 time participants was significantly higher than that of 3 times, 4 times or 5 times participants in the upper center, lower left, lower center, and lower right areas. There was a significant improvement in CPI from $2.59{\pm}1.14$ to $1.41{\pm}1.54$ (p<0.001) and positive oral behavioral change (daily tooth brushing frequency from $2.27{\pm}0.73$ to $2.54{\pm}0.90$) before and 5 years after the program. However, the program did not prevent tooth loss as the numbers of the remaining teeth significantly reduced from $23.77{\pm}1.84$ to $21.95{\pm}2.03$ over 5 years. We showed that running the community oral health program for the elderly for more than three years might have positive effects on the periodontal health of participants.

• 한국물환경학회지
• /
• 제22권6호
• /
• pp.1107-1108
• /
• 2006

As expanding municipal and industrial areas since started the economic development plan in earnest in 1970's, the water resource, mainly river surface water has been seriously polluted. Nevertheless, being upgraded in their treatment technologies for the drinking water, the safety has been issued one of crucially social problem in Korea. The water authorities has tried to improve the quality such as amending the drinking water quality standard to be monitored; hazardous chemicals and microorganis have been added and now 55 items, before 47 items, since in 2002. The Water Authorities of Seoul, the capital city of Korea, planned to assess the safty of drinking water quality after amended the standard. This study was conducted to assess the risk due to polluted chemicals including 21 heavy metals, VOCs, pesticides, PAHs, DBPs and organic chemicals among the regulated items. The risk assessment were undertaken hazard identification, exposure assessment, dose-response assessment and risk characterization. For the exposoure assessment, tap water, bottled water and purified water were sampled and analyzed in February, 2004. Risk characterization of detected chemicals was categorized into carcinogenecity and noncarcinogenecity, and estimated the excess of carcinogens and compapared with the reference dose (RfD) of noncarcinogenns. The excess risk of carcinogens from samples were considered comparatively in the acceptable levels; $10^{-6}$ for cancer risk and hazard quotient (HQ) 1.0 for noncancer risk. The deteced levels were estimated in $10^{-5}{\sim}10^{-6}$ of cancer risk and below 1.0 of HQ of noncancer risk. While three kinds of water were determined within the acceptal levels, DBPs were detected in tap water and purified were and some undesireable chemicals such as more fluoride detected rather than the quality stanadard. For the drinking water safety, it shoud be continuously monitored, assessed and managed as well risk communiction between the authoritis and public.

• 멤브레인
• /
• 제27권5호
• /
• pp.458-467
• /
• 2017

본 연구는 열유도 상분리법(thermally induced phase separation, TIPS)을 사용하여, 수처리 분리막에 적용하기 위해, 응고조의 열용량의 변화를 위해 서로 다른 두 용액의 함량을 조절하였다. 또한, 온도의 변화를 통해 분리막의 구조 변화에 대하여 관찰하였다. 분리막을 제조하기 위한 소재로는 수처리 분리막에 주로 이용되는 기계적 물성과 내화학성이 우수한 poly (vinylidene fluoride)(PVDF)를 사용하였고, 첨가제로 실리카를 이용하였다. 희석제는 PVDF와 호환성이 좋은 dioctyl phthalate (DOP), dibutyl phthalate (DBP)를 사용하였다. 응고액의 함량 변화에 따른 열용량 변화에 따라 제조된 분리막의 구조를 관찰하기 위해 SEM 이미지를 촬영하였다. 열용량이 증가할수록 PVDF의 결정화 속도가 느려져 큰 기공을 나타내며 열용량이 작을수록 결정화 속도가 증가하여 작은 기공이 생기는 것을 확인하였다.

• 한국치위생학회지
• /
• 제12권4호
• /
• pp.707-714
• /
• 2012

Objective : This study came to be carried out in order to develop oral health education program for maintaining adolescents' oral health and to be helpful for qualitative improvement in prevention program by surveying the awareness and behavior on preventive method of dental caries in adolescents. Method : The collected materials of totally 1,100 people who responded were carried out frequency analysis by using SPSS 12.0(Statistical Package for the Social Science). Results : 1. As for the results of awareness on fluoride effect and sealant effect, the students with response to 'effect of preventing decayed tooth' were indicated to be the highest. It was indicated to be the highest in girls as for gender and in the 2nd grade as for school year. (p<0.05). 2. As for the results of being created when eating sweet food and carbonated drink, the students with response as saying that 'a decayed tooth occurs well' were indicated to be the highest. 4. As for the results on the aim of visiting dental clinic, the students with response as saying of 'visiting for having treatment' when tooth is painful were indicated to be the highest. Conclusion : Synthesizing this study, the students' awareness on preventive method of dental caries was high. But the practice on regular check-up or diet was indicated to be low. Through oral health education, the adolescents should be not only delivered information or knowledge, but also changed habit and behavior.

• 디지털융복합연구
• /
• 제14권12호
• /
• pp.537-544
• /
• 2016

본 연구의 목적은 기초 수급자들을 대상으로 실시하고 있는 노인들의 불소도포 및 스켈링 사업을 통하여 그들의 구강건강 상태와 구강건강 관련 행태를 살펴보고 잔존 치아 수와의 관련성에 대하여 조사하고자 한다. 65세이상 기초 수급자 노인 660명을 대상으로 자기기입식 설문조사를 시행하였고, 구강검진을 통하여 틀니사용 유무와 잔존 치아 수 등을 조사하였다. 연령이 증가함에 따라 잔존 치아 수는 줄어들었으며, 성별, 연령, 구강위생용품의 사용, 자가 구강상태 진단, 점심 식사 후 칫솔질 유무에 따라서 잔존 치아 수에 차이가 나타났고 통계적으로도 유의하였다(p<0.05). 잔존 치아 수는 대상자 개인의 구강 예방에 대한 관심과 노력으로 예방이 가능하다. 따라서 노인들의 구강건강 행태가 잔존 치아 수에 미치는 융복합적 용인을 샆펴보고, 취약계층에 대한 예방 진료의 확대와 보건관리의 제공을 유지하기 위한 구강관리 프로그램이 지속적으로 제공되었으면 한다.

• Membrane and Water Treatment
• /
• 제6권3호
• /
• pp.205-224
• /
• 2015

A novel hydrophilic poly (vinylidene fluoride)/poly (p-phenylene terephthalamide) (PVDF/PPTA) blend membrane was prepared by in situ polycondensation of p-phenylene diamine (PPD) and terephthaloyl chloride (TPC) in PVDF solution with subsequent nonsolvent induced phase separation (NIPS) process. For comparison, conventional solution blend membrane was prepared directly by adding PVDF powder into PPTA polycondensation solution. Blend membranes were characterized by means of viscometry, X-ray photoelectron spectroscopy (XPS), Field Emission Scanning Electron Microscopy (FESEM). The effects of different blending methods on membrane performance including water contact angle (WCA), mechanical strength, anti-fouling and anti-compression properties were investigated and compared. Stronger interactions between PVDF and PPTA in in situ blend membranes were verified by viscosity and XPS analysis. The incorporation of PPTA accelerated the demixing rate and caused the formation of a more porous structure in blend membranes. In situ blend membranes exhibited better hydrophilicity and higher tensile strength. The optimal values of WCA and tensile strength were $65^{\circ}$ and 34.1 MPa, which were reduced by 26.1% and increased by 26.3% compared with pure PVDF membrane. Additionally, antifouling properties of in situ blend membranes were greatly improved than pure PVDF membrane with an increasing of flux recovery ratio by 25%. Excellent anti-compression properties were obtained in in situ blend membranes with a stable pore morphology. The correlations among membrane formation mechanism, structure and performance were also discussed.

• Membrane and Water Treatment
• /
• 제7권3호
• /
• pp.241-255
• /
• 2016

In this study, the treatability of arsenic (As) contaminated water by direct contact membrane distillation (DCMD) at different delta temperatures (${\Delta}T$) 30, 40 and $50^{\circ}C$ has been investigated. Two different pore sizes ($0.22{\mu}m$ and $0.45{\mu}m$) of hydrophobic membranes made of polyvinylidene fluoride (PVDF) were used. The membrane pore sizes, the operating temperatures, the feed solution As concentration and conductivity have been varied during the experimental tests to follow the removal efficiency and flux behavior. Both membranes tested had high removal efficiency of arsenite (As (III)) and arsenate (As (V)) and all permeates presented As concentration far lower than recommended $10{\mu}g/L$ of world health organization (WHO). As concentration was below detection limit in many permeates. Conductivity reduction efficiency was over 99% and the transmembrane flux (TMF) reached $19L/m^2.h$ at delta temperature (${\Delta}T$) of $50^{\circ}C$ with PVDF $0.45{\mu}m$ membrane. The experimental results also indicated that $0.45{\mu}m$ pore sizes PVDF membranes presented higher flux than $0.22{\mu}m$ pore sizes membranes. Regardless of all operating conditions, highest fluxes were observed at highest ${\Delta}T$ ($50^{\circ}C$).

• Membrane and Water Treatment
• /
• 제7권3호
• /
• pp.209-221
• /
• 2016

As a highly hydrophilic fibrillar mineral in nature, attapulgite (ATP) is a promising new additive for preparation of ultrafiltration (UF) hybrid membrane. In this work, ATP particles, which were grafted with a new Gemini surfactant of Ethyl Stearate-di(octadecyl dimethyl ammonium chloride) to detach the crystal bundles to single crystal and enhance the uniform dispersion in an organic polymer matrix, were incorporated into poly(vinylidene fluoride) (PVDF) matrix, and PVDF/Gemini-ATP hybrid membranes for adsorptive removal of Ni(II) ions from aqueous solution were prepared via a phase inversion method. Chemical composition, crystalization and morphology of the modified ATP were characterized by Fourier transform infrared spectroscopy (FTIR), Transmission electron microscope (TEM) and X-ray diffraction (XRD), respectively. The morphology of the hybrid membrane was characterized by Scanning electron microscopy (SEM), the performance of permeability, hydrophilicity and adsorption of Ni(II) ions were studied, and the adsorption kinetics of the PVDF/ATP hybrid membranes were particular concerned. The results showed that the hybrid membrane displayed a good thermal stability and hydrophilicity. Comparing with PVDF membrane, the hybrid membrane possessed good adsorption capacity for Ni(II) ions, and the adsorption kinetics fit well with Lagergren second-order equation.