타타늄의 열처리 조건에 따른 동전위 양극분극특성 및 표면 미세구조 변화

주동현,이용렬,정영화,양홍서,박상원,이도재,송호준,박영준 大韓齒科器材學會 2002 대한치과재료학회지 Vol.29 No.2

The corrosion resistance of metallic implants is essential for successful implant osseointegration. Moreover, the implant surface should have appropriate surface roughness for the attachment of the osteoblast and collagen fibrils. When titanium is exposed to air a thermodynamically very stable oxide film is formed at once. This oxide is very thin and yet it protects the metal from corrosion instantaneously. However, the oxide would not be ideal, and it would be supposed that the state of oxide film would be various by the different conditions when it is formed. The objective of this study was to evaluate the electrochemical properties and surface microstructural changes of titanium after passivation treatment or exposure to high heat (in vacuum or in air). ASTM grade 2 commercially pure titanium (Ti) disks of 10㎜ diameter were wet ground and polished with 240 and 600 grit SiC, and then ultrasonically cleaned with distilled water and ethanol. Cleansed as-received samples (As-R group) were passivated with 30% nitric acid solution at 50℃ for 15 minutes to make the Pas group. The Std-V samples were made by treating the Ti disks in vacuum quartz tube (10^-8 Torr) at 530℃ for 40 min for stress relieving, followed by annealing at 700℃ for 90 min, and then slow cooling to room temperature. The Std-A samples undergo identical procedure as the Std-V group except that it is done in air. For 530℃-V samples, Ti disks were heated at 530℃ for 40 minutes and slow cooled to room temperature. The 1000℃-V samples were produced by heating Std-V specimens again at 1000℃ for 2 hr, followed by cooling to room temperature. 530℃-A and 1000℃-A samples were also prepared. Potentiodynamic anodic polarization measurement, SEM, AFM and XRD analysis were performed to evaluate the effects of the various treatments. The difference in the mean values of E_corr between groups showed statistically significant difference (P<0.05), but that of I_corr did not show significance (P>0.05). When Ti surface was passivated there was a shift of corrosion potential (E_corr) in the noble direction and a lower corrosion current density (I_corr) value. Std-A samples showed most noble E_corr value among the tested groups. 530℃-V samples showed more noble E-corr than other tested groups except Std-A group. 1000℃-V samples showed more noble E-corr than those of Std-V sample. In the case of Std-, 530℃- and 1000℃-groups, -A sub-groups showed better corrosion resistant characteristics than -V sub-groups in regard to E-corr and I_corr values. In the SEM observations, the surfaces of the As-R samples showed only scratch line on smooth surface. In Pas samples, thick oxide layer covered the surface under high magnification observation. 530℃-A samples were covered by oxide granules, and Std-A samples had 25~50 nm-thick acicular oxides. The 1000℃-A samples were covered by coarse oxide crystals with a granule diameter of 0.1~0.6 μm having a gross appearance of milky white color, which was identified by XRD as a rutile. On the other hand, 1000℃-V samples showed an Widmansta¨tten structrue of which the orientation of the lattice is formed along crystallographic planes of the parent crystals. On the AFM observation, 530℃-A samples showed RMS roughness of 79.38 nm which is 5 times rougher than those of the As-R samples. Std-A sample had a roughness of 330.47 nm which is about 20-times rougher than that of the As-R sample. 1000℃-A samples were covered by coarse granular oxides and the roughness were about 0.56 μm. Vacuum sub-group samples showed a more smooth surface than air sub-group samples, and the oxide film was more dense. Due to variability of the surface treatment and heat treatment conditions, the process of the oxide formation seems to be affected thereby making the corrosion properties and surface micro-morphology different. However, more various electrochemical analysis together with surface analysis, and an investigation for the effects of those on the osteoblast cell adhesion and calcium phosphate apposition are needed for the improvement of the osseointegration rates of the titanium implants.

Microcapsule을 이용한 생물학적 처리방법에 의한 오·폐수 중의 탈질소화에 관한 연구

이상호,최재선,송주영 國立 昌原大學校 産業技術硏究所 1996 産技硏論文集 Vol.10 No.-

Various experiments were conducted to test denitrification ability of immobilized Paracoccus denitrificans on calcium alginate microcapsules from synthetic waste water. Paracoccus denitrificans one of a typical denitrifying strain, showed good denitrification ability on both as a immobilized strain and as a strain itself. Calcium alginate microcapsule wall did'nt play a role to interrupt the diffusion rate of substrate in and product out. This system showed a possibility for the development of denitrifying apparatus if the immobilization technique could be improved.

플라이애쉬 콘크리트의 特性에 미치는 굵은 骨材 最大値數의 影響에 관한 實驗的 硏究

김덕현,유영주,이상수,송하영,김을용 한밭대학교 2004 한밭대학교 논문집 Vol.21 No.-

In this study, the experiment was carried out to investigate and analyze the influence of coarse aggregate's maximum size and Fly Ash replacements ratio on the properties of concrete. The main experimental variables were water/cement ratio 45 and 65(%), maximum size of coarse aggregate 15, 25 and 40(mm), Fly Ash replacements ratio 0, 10, 20(%). According to the test results, the principal conclusions are summarized as follows. 1) The slump and flow of fresh concrete were found to be higher in the order of maximum size of coarse aggregate 15, 25 and 40(mm), also in the order of Fly Ash replacements ratio 0, 10, 20(%). 2) The compressive strength of hardened concrete were found to be lower in the order of maximum size of coarse aggregate 15, 25 and 40(mm). While, Fly Ash replacements ratio increases in age 7days, showed tendency that compressive strength increases together. but, age 28, 56(day) were showed opposite tendency.

CHEMISTRY : Protective effect of arabinose and sugar beet pulp against high glucose-induced oxidative stress in LLC-PK1 cells

( Yeong Bok Song ),( Boh Kyung Kim ),( Mi Jin Choi ),( Yeong Ok Song ),( Eun Ju Cho ) 부산대학교 김치연구소 2012 김치의 과학과 기술 Vol.15 No.-

The protective effects of L-arabinose and sugar beet (SBP) on high glucose-induced oxidative stress were investigated using LLC-PK cells. Under the high glucose-induced cellular oxdative model, the treatment of 45 mM of glucose led to the decrease in cell viability and increase in lipod peroxidation_However. L-arabinose and SBP significantly inhibited the high glucose-induced cytotoxicity and lipid per-oxidation. In addition, the formation of nitric oxide(NO) was increased by the treatment of 45mM glu-cose. while the treatment of L-arabinose or SBP inhibited signigicantly the NO formation compared with high glucose-treated control. The superoxide anion production of groups treated whth L-arabinose or SBP was significantly lower than that of the control treated with high glucose. Futhermore. L-arabinose and SBP elevated the glucose uptake. resulting in lower glucose concentration compared with non-treated control. High glucose levels induced the overexpressions of bax. inducible NO synthase and cyclooxygen-ase-2. but L-arabinose or SBP treatrnent down-regulated the expressions of these genes. Arabinose and SBP also inhibited the expression of nuclear factor-kappa B induced by 45mM glucose in LLC-PK cells. In particular, arabinose exhibited stronger inhibitory activities on high glucose-induced oxdative stress than SBP did. These findings indicate that L-arabinose and SBP are promising antioxidative agents with protective activities against hyperglycemia.

Enzyme Immobilized Reactor Design for Ammonia Removal from Waste Water

Song, Ju-Yeong,Chung, Soo-Bae The Korean Society for Biotechnology and Bioengine 1997 Biotechnology and Bioprocess Engineering Vol.2 No.2

Removal of nitrogen compound from waste water is essential and often accomplished by biological process. To prevent washout and to develop an efficient bioreactor, immobilization of sutibal microorganisms could be sensible approach. Strains and permeabilized cell encapsulated in cellulose nitrate microcapsules and immobilized on polystyrene films were prepared by the method described in the previous study. In the wastewater treatment system, nitrification of ammonia component is generally known as rate controlling step. To enhance the rate of nitrification, firstly nitrifying strains Nitrosomonas europaea(IFO14298), are permeabilized chemically, and immobilized on polystyrene films and secondly oxidation rates of strain system and permeabilized strain system are compared in the same condition. with 30 minute permeabilized cells, it took about 25 hours to oxidize 70% of ammonia in the solution, while it took about 40 hours to treat same amount of ammonia with untreated cells. All the immobilization procedures did not harm to the enzyme activity and no mass transfer resistance through the capsule well was shown. In the durability test of immobilized system, the system showed considerable activity for the repeated operation for 90 days. With these results, the system developed in this study showed the possibility to be used in the actual waste water treatment system.

성인 원발성 초점성 사구체 경화증의 예후인자

송영수 ( Song Yeong Su ),최훈영 ( Choe Hun Yeong ),유태현 ( Yu Tae Hyeon ),강신욱 ( Kang Sin Ug ),이중민 ( Lee Jung Min ),정현주 ( Jeong Hyeon Ju ),이호영 ( Lee Ho Yeong ),한대석 ( Han Dae Seog ),최규헌 ( Choe Gyu Heon ) 대한신장학회 2004 Kidney Research and Clinical Practice Vol.23 No.1

배 경 : 성인 원발성 초점성 분절형 사구체 경화증은 성인 신증후군의 한 원인으로 과거에는 치료에 대한 반응이 적은 것으로 생각되었으나 최근에는 치료의 관해율과 예후가 향상되고 일부 임상 및 병리 지표들은 예후 측면에서 의미가 있다고 보고되고 있다. 그러나 현재까지 일관되게 보고된 예후 인자는 없는 실정이다. 이에 저자는 치료 반응에 대한 예측인자와 신부전의 진행에 영향을 주는 위험인자를 알아보고자 하였다. 방 법 : 1991년부터 2002년까지 연세의료원에서 일차성 초점성 분절형 사구체 경화증으로 진단받은 성인 환자 40명을 대상으로 진단시 임상 및 병리조직학적 지표를 후향적으로 분석하였다. 결 과 : 신생검시 환자 26명 (65%)에서 신증후역의 단백뇨가 있었으며, 14명 (35%)에서 비신증후역의 단백뇨가 있었다. 신증후역의 단백뇨 환자군이 비신증후역의 단백뇨 환자군보다 혈청 크레아티닌치가 높았으며 (p<0.05), 혈청 알부민과 총 콜레스테롤치를 제외하고 두 군간에 기타 임상 및 병리조직학적 지표의 차이는 없었다. 27명에게 면역억제 치료를 하였으며 15명 (55.6%)에서 반응이 있었고, 치료 반응군과 무반응군 간에 임상 및 병리조직학적 지표의 차이는 없었다. 추적관찰 기간동안 정상 신기능을 유지한 군과 만성 신부전으로 진행한 군을 비교하였을 때 진단시 혈청 크레아티닌치의 증가와 치료에 대한 반응 유무가 의미있는 예후인자로 분석되었다 (p<0.05). 신 생존분석시 치료군이 치료하지 않은 군보다 생존율이 높은 경향을 보였으나 통계학적인 차이는 없었고 (p>0.05), 치료 반응군은 무반응군보다 의미있게 높은 생존율을 보였다 (P<0.05). 결 론 : 진단시 혈청 크레아티닌치의 증가 소견이 있거나 치료에 반응이 없는 환자들은 불량한 예후를 보일 수 있으므로 보다 집중적인 치료와 주기적인 신기능의 관찰이 필요할 것으로 보인다. Background : Primary focal segmental glomerulosclerosis (FSGS) is a cause of nephrotic syndrome in adult. Although primary FSGS has been known to be refractory to treatment, recent studies reveal higher remission rate and better prognosis. And it has been reported that some clinical and histopathologic paramenters are significant to prognosis. But, confirmative prognostic indices remain to be defined. In order to further clarify the prognostic factors for therapeutic response and risk factors for progression to chronic renal failure (CRF), we reviewed the medical records of primary adult FSGS patients. Methods : Forty-adult patients diagnosed as primary FSGS between 1991 to 2002 were enrolled. We retrospectively analyzed the clinical and histopathological parameters of all patinents at the time of renal biopsy. In addition, the therapeutic responses to immunosuppressants and the renal survival were analyzed. Results : At the time of renal biopsy, 26 patients (65%) had proteinuria of the nephrotic range and 14 patients (35%) had proteinuria of the non-nephrotic range. The serum creatinine level was higher in nephrotic-ranged patients than that in non nephroticranged patients (p<0.05). The other parameters were not significantly different between two groups. Twenty-seven patients were treated with immunosuppressants and 15 patients (55.6%) responded to the treatment. There was no significant difference in clinical or histopathological variables between the responders and the non-responders. High serum creatinine level at diagnosis and responsiveness to treatment appeared to be significant as risk factors for progression to CRF (p<0.05). The paticnts treated with immunosuppressants had longer survival period, compared with those without treatment. And the responders had significantly longer survival period compared with the non-responders (p<0.05). Conclusion : The patients with initial impairment of renal function or poor response to therapy may have worse prognosis, and the intense treatment with regular follow-up of renal function should be recommended for these patients. (Korean J Nephrol 2004;23(1)36-45)

구강질환과 감염성 심내막염

조주영 ( Ju Yeong Jo ),조수진 ( Su Jin Ju ),송희상 ( Hii Sang Song ) 조선대학교 치의학연구원 2014 Oral Biology Research (Oral Biol Res) Vol.38 No.2

Despite significant improvements in medical treatments, infective endocarditis remains a very serious health problem with considerable morbidity and mortality. Indeed, the frequency of severe endocarditis has increased in recent years, particularly in association with antibiotic-resistant pathogens. Accordingly, infective endocarditis constitutes a major challenge for clinicians and a considerable burden for the health-care system. In addition, dental disease has long been associated with increased prevalence of infective endocarditis. Many reports have demonstrated that antibiotics given before a dental procedure can reduce the risk of bacteremia from oral disease. Here, we review recent treatments for prophylaxis of infective endocarditis before dental procedure.

Carbonic Anhydrase 를 고정화 시킨 인공허파에서 이산화탄소의 전달현상에 관한 수학적 해석

송주영 ( Ju Yeong Song ) 한국화학공학회 1994 추계학술발표논문집 Vol.- No.-

Harris-Galante 무시멘트형 비구컵을 이용한 인공고관절 전치환술 후 polyethylene liner의 분리

송주현 ( Song Ju Hyeon ),정진영 ( Jeong Jin Yeong ),이한용 ( Lee Han Yong ),고해석 ( Go Hae Seog ),유기원 ( Yu Gi Won ),강용구 ( Kang Yong Gu ),황희주 ( Hwang Hui Ju ),강인규 ( Kang In Gyu ) 대한고관절학회 2002 Hip and Pelvis Vol.14 No.3

Anti-Lipogenic Effects of Tannic Acid in 3T3-L1 Adipocytes and in High Fat Diet-fed Rats

( Hyun Ju Kim ),( Ye Rang Yun ),( Yeong Bok Song ),( Yeong Ok Song ) 부산대학교 김치연구소 2009 김치의 과학과 기술 Vol.12 No.-

Anti-lipogenic effects of tannic acid on 3T3-L1 adipocytes as well as on rats fed high fat diet (HFD) were investigated. Tannic acid stimulated lipolysis through suppression of the leptin secretion and an increase of glycerol release in a dose dependent manner in 3T3-L1 adipocytes. For animal study, the rats were fed either HFD or HFD supplemented with 1%(w/w) tannic acid (HFDT) for 12 weeks, respectively. Body weight gain, 1iver weight, and visceral fat mass in rats fed HFDT were significantly decreased compared to those of rats fed HFD. The lipid profiles of HFDT group were significantly decreased compared with HFD group in the serum and 1iver, whereas fecal total cholesterol excretion was increased in HFDT group. These results suggest that anti-lipogenic effect of tannic acid in 3T3-L1 adipocytes and in rats fed HFD may be due to the stimulation of lipolysis and the reduction of lipid levels.