몇 가지 항균제가 시험관내에서 내독소와 TNF-α, IL-6 분비에 미치는 영향

최정현,문건웅,김명훈,이동건,박윤희,김상일,김태연,유진홍,김양리,신완식,강문원 대한화학요법학회 1997 대한화학요법학회지 Vol.15 No.2

To evaluate antibiotic-induced endotoxin release(AIER) and its correlation with some cytokines, we measured endotoxin level and tumor necrosis factor alpha(TNF-α) and interleukin6(IL-6) production in mononuclear cells in vitro after exposure of Pseudomonas aeruginosa to antibiotics belonging to different class with two extreme concentrations. The tested concetration of antibiotics were set up according to peak serum level. The low concetration of ceftazidirne and low concentration of imiperiem increased AIER, but high concentration of ceftazideme, high concentration of ciprofloxacin, high concentration of cefoperazone/sulbactam, high concentration of amikacin, and high concentration of meropenem reduced AIER.Interestingly, combined treatment of these antibiotics markedly reduced AIER, But the major cyotkines, TNF-α and IL-6 were not affect by type and concettration of antibiotics, combined treatment of antibiotics, and level of endotoxin released by antiboitics. In this study, we observed AIER was different according to type of antibiotics, concentration of antibiotics, and combination of antibiotics, But AIER had poor correlation with TNF-α and IL-6 in Pseudomonas aeruginosa. It suggests that cytokine release is not solely dependent to endotoxin, but more complex cascade is needed. More invesfigations, such as endotoxin induced cytokine mRNA expression, relationship with penicillin-binding proteins and endotoxin-neutralizing effect of antibiotic itself, must be performed.

有機製品의 物性改質에 必要한 Silicone 架橋劑開發에 관한 硏究

韓貞璉,梁在乾,鄭一鉉,裵長淳 단국대학교 1985 論文集 Vol.19 No.-

Alkoxysilanes were synthesized by me alcoholysis of trichbromethyhilanc having trifunctional group with corresponding alcohols under sodium alkoxide or HCl acceptor. The yields of the products were more than 80%. It was found that the rate of the hydrolysis of ethoxysilane was faster than methoxysilane. Hexamethyldisilazanes were synthesized by the reaction of chlorotrimethylsilane with ammonia gas or ammonium liquid solution. The yields of the products were 86% and 26% respectively. As the results of hydrolysis of disilazanes prepared under acidic, neutral, and alkali solutions, the rate of the hydrolysis was increased with the order of alkali, neutral, and acidic solution. After synthesizing α,ω-dichloromethylsiloxane by the reaction of diethoxydimethylsilane with dimethyldichlorosilane, α,ω-dichloromethylsiloxanol with terminal hydroxyl group was prepared by the hydrolysis of the product. p-Phenylene-bis-dimethylchlorosilane was prepared through Grignard reaction of p-dibromobenzene with dimethyldichlorosilane, and then p-phenylene-bis-dimethyltydroxysilane was synthesized by the hydrolysis of p-phenylene-bis-dimethylchlorosilane. α,ω-dichloromethylsiloxane

흡입관에 부착된 이젝터내의 유동특성에 관한연구

이행남,박길문,모양우,이덕구,설재림,김건일 朝鮮大學校 機械技術硏究所 2004 機械技術硏究 Vol.7 No.2

The ejector is used to get low pressure, and it has been applied to a lot of industry field like the heat engine, the fluid instrument power plant, the food industry, environment industry etc. because there are not any problem even it is mixed with kinds of liquid, gas, and solid. The flow characteristics in diffuser are investigated by PIV and CFD. The agreement between numerical analysis and experiment shows the validity of this study and the results of this study would be useful to the engineers who design for the flow systems for heating, ventilation, air conditioning and wastewater purification plants.

Comparison of changes in the buccal keratinized mucosa between the minimally-invasive crestal incision and apically-positioned full-thickness flap methods for stage-two implant surgery

( Keon-il Yang ),( Jun-mo Yang ),( Ki-won Lee ),( Won-pyo Lee ),( Byung-ock Kim ),( Sang-joun Yu ) 조선대학교 치의학연구원(구 조선대학교 구강생물학연구소) 2020 Oral Biology Research (Oral Biol Res) Vol.44 No.1

Stage-two implant surgery, which exposes the implant platform to connect the healing abutment, affects the width of the peri-implant keratinized mucosa thereby affecting the long-term prognosis of the implant. The purpose of this study was to compare the changes in the width of the peri-implant buccal keratinized mucosa between the minimally-invasive crestal incision (MCI) procedure and the apically-positioned full-thickness flap (APFTF) method during stage-two implant surgery. A total of 74 implants were placed in 41 patients. The MCI group included 27 implant cases wherein, healing abutments were connected after stage-two implant surgery using the MCI in 18 patients. The APFTF group comprised 47 implant cases wherein, healing abutments were connected after stage-two implant surgery using the APFTF method in 23 patients. The buccal keratinized mucosa widths (BKMW) of the healing abutment and prosthesis were measured at the mesial, central, and distal aspects after the stage-two surgery and the final restoration. A decrease in the BKMW in both groups after stage-two implant surgery was observed when compared with those after the final restoration; furthermore, the BKMW was significantly lower after stage-two implant surgery in the MCI group (p <0.001). No statistically significant difference in BKMW was noted between the MCI and APFTF groups at any point. These results reveal that the APFTF method was more effective than MCI in terms of preserving the buccal peri-implant keratinized mucosa during stage-two implant surgery.

Maxillary sinus floor augmentation using two different ratios of cancellous and cortical freeze-dried bone allograft mixtures: clinical and histological outcomes

Keon-Il Yang,Choong-Seop Ji,Ock-Hyun Cho,Ho-Jin Yun,Won-Pyo Lee,Byung-Ock Kim,Sang-Joun Yu 조선대학교 치의학연구원 2022 Oral Biology Research (Oral Biol Res) Vol.46 No.1

The aim of this study was to evaluate the clinical and histologic outcomes of sinus floor augmentation using mixtures of cancellous and cortical freeze-dried bone allograft (AG) at two different ratios (5:5 and 3:7). The sinuses of 21 patients were grafted with the two types of mixed allografts. Cone-beam computerized tomography scans were obtained, and the radiographic parameters measured were residual bone height and bone gain after bone healing. Clinical examinations and histologic analyses were performed 6 months after the grafting procedure. Twenty implant sites in the 5:5 mixed AG group and 22 implant sites in the 3:7 mixed AG group were analyzed. The bone gain after bone healing was 13.0±3.1 mm in the 5:5 group and 14.5±3.5 mm in the 3:7 group. The survival rates of the implants in both groups were 100% during follow-up periods. The newly formed bone was 29.9±16.6% in the 5:5 AG group and 25.1±10.1% in the 3:7 AG group. Moreover, the percentage of residual graft material was 15.2±12.7% in the 5:5 AG group and 20.4±12.1% in the 3:7 AG group. The connective tissues were 55.0±14.0% and 54.6±10.0% in the 5:5 and 3:7 AG groups, respectively. The two different ratios of AG presented with different histological outcomes after bone healing. Additionally, adequate new bone formation for the placement of implants was achieved following maxillary sinus augmentation using both types of AG.

Clinical and Microbiological Study about Efficacy of Air-polishing and Scaling and Root-planing

Keon-Il Yang,Do-Young Park,Byung-Ock Kim,Sang-Joun Yu 대한구강생물학회 2015 International Journal of Oral Biology Vol.40 No.2

The efficacy of air-polishing on subgingival debridement, as compared to scaling and root planning (SRP), was evaluated clinically and microbiologically. Fifteen patients diagnosed as chronic periodontitis, and having single-root tooth over 5 mm of pocket depth symmetrically in the left and right quadrant, were investigated. Subgingival debridement was performed by SRP and air-polishing. The results were evaluated and compared clinically and microbiologically. Probing pocket depth (PPD), bleeding on probing (BOP), relative attachment level (RAL) and change of gingival crevicular fluid (GCF) were assessed before treatment, and at 14 and 60 days after treatment. Microbial analysis was done pre-treatment, post-treatment, and at 14 and 60 days after treatment. Results of air polishing showed that post treatment, the PPD and BOP decreased, and attachment gain was observed. There was no clinical difference when compared to SRP. The volume of GCF decreased at 14 days, and increased again at 60 days. Compared to SRP, there was a statistical significance of the volume of GCF at 60 days in air-polishing. In the microbial analysis, high-risk bacteria that cause periodontal disease were remarkably reduced. They decreased immediately after treatment, but increased again with the passage of time. Thus, our results show that subgingival debridement by air-polishing was effective for decrease of pocket depth, attachment gain, decrease of GCF and inhibition of pathogens. Further studies are required to compare air-polishing and SRP, considering factors such as degree of pocket depth and calculus existence.

Minimally invasive 2nd stage surgery for preservation of keratinized gingiva around implant: Case reports

( Keon-il Yang ),( Kyung-hyun Lee ),( Jung-hwa Kim ),( Sang-joun Yu ) 조선대학교 치의학연구원(구 조선대학교 구강생물학연구소) 2018 Oral Biology Research (Oral Biol Res) Vol.42 No.3

Implant secondary surgery is an operation that exposes the implant fixture into the oral cavity. Depending on the surgical procedure, keratinized gingiva surrounding the implant may be affected, that may affect long-term prognosis of the implant. The purpose of this case report is to introduce a minimally invasive 2nd stage surgery and to evaluate its clinical features and effect on preservation of keratinized gingiva. Minimally invasive 2nd stage surgery was performed in three patients that had completed first stage implant surgery. The width of keratinized gingiva was measured immediately after surgery and after completion of prosthesis. As a result, the width of keratinized gingiva was preserved, patient's discomfort was reduced, and the operation duration was shortened.

Effect of autogenous tooth bone graft with membrane on Class II furcation defects in dogs: A histologic and histomorphometric study

( Keon-il Yang ),( Ah-young Cho ),( Jin-young Yang ),( Hong-in Shin ),( Won-pyo Lee ),( Byung-ock Kim ),( Sang-joun Yu ) 조선대학교 구강생물학연구소 2018 Oral Biology Research (Oral Biol Res) Vol.42 No.1

The study evaluated the efficacy of combining autogenous tooth bone grafts with membranes in surgically created class II furcation defects. Thirty teeth of 10 dogs were assessed. Furcation defects (5 × 4 × 3 mm³) were created in the lower third and fourth premolars. Defects in the control, experimental-1, and experimental-2 groups were treated with non-resorbable membranes only, autogenous tooth bone grafts with non-resorbable membranes, and autogenous tooth bone grafts with resorbable membranes, respectively. Healing patterns were observed 4 to 8 weeks after treatment. Mesio-distal sections were obtained and stained with hematoxylin and eosin, and histological and histomorphometrical analyses were performed. Four weeks after treatment, connective tissue and autogenous tooth bone graft materials with newly formed bone were observed. Partial recovery of periodontal ligament-like tissue and formation of cementum-like tissue at root surfaces also occurred. Eight weeks after treatment, mature bone tissue formation was noted. In addition, regular thickness of cementum-like tissue at root surfaces, and improved periodontal ligament-like tissue were observed. Areas of newly formed tissue were 92.2% ± 13.0%, 97.4% ± 4.4%, and 98.1% ± 2.8% at 4 weeks after treatment, and 96.7% ± 3.7%, 96.8% ± 5.7%, and 99.6% ± 0.8% by 8 weeks post-treatment, in the control, experimental-1, and experimental-2 groups, respectively. Regeneration of defective tissues occurred in the experimental group compared with the control group, but not significantly. This study showed that combining autogenous tooth bone grafts with membranes in class II furcation defects improves healing efficiency.

혈관화 개재 골막-결합조직 이식술을 이용한 치조제 증대술 증례보고

양건일 ( Keon Il Yang ),한정균 ( Jeong Gyun Han ),조아영 ( Ah Young Cho ),양진영 ( Jin Young Yang ),유상준 ( Sang Joun Yu ) 조선대학교 치의학연구원 2013 Oral Biology Research (Oral Biol Res) Vol.37 No.1

A total of three patients underwent vasculized interpositional periosteal-connective tissue grafting for alveolar ridge augmentation. All patients had a Seibert Class III alveolar defect in which the alveolar ridge was retracted horizontally and vertically in maxillary anterior area. Fixed prosthetics were planned in order to restore missing teeth. Scaling and root planing were completed 1 month before the ridge augmentation. For proper restoration of alveolar ridge, vasculized interpositional periosteal-connective tissue grafting with or without alloplast (synthetic bone) was performed, followed by primary closing of the surgical site and soft tissue augmentation. Stitches were taken out 2 weeks after surgery, and no complications were observed such as infection or inflammation. Alveolar ridge became vertically and horizontally thicker compared to before surgery, which made it possible to restore esthetic prosthetics. These cases show that it is possible to restore esthetic alveolar ridge for fixed prosthetics using vasculized interpositional periosteal-connective tissue grafting.

강제 맹출술과 치은섬유절단술을 동반한 임상치관연장술

양건일 ( Keon Il Yang ),정민구 ( Min Gu Jung ),조아영 ( Ah Young Jo ),양진영 ( Jin Young Yang ),유상준 ( Sang Joun Yu ),김병옥 ( Byung Ock Kim ) 조선대학교 구강생물학연구소 2012 Oral Biology Research (Oral Biol Res) Vol.36 No.1

Three patients (2 maxillary anterior teeth and 1 maxillary second premolar) underwent clinical crown lengthening procedures with forced eruption. All teeth had undergone complete root canal treatment prior to the procedure. Using an elastic band, extrusion of teeth was planned; during a 2-month period of extrusion, activation and fiberotomy were performed within a 2-week period. Following an 8-week period of maintenance, gingivectomy without bone surgery was performed. The patients were then referred to the department of prosthodontics for the fi nal prosthodontic restoration. After completion of the fi nal prosthodontic restoration, esthetically satisfactory results were reported in all three cases. These cases demonstrate the safety and simplicity of the clinical crown lengthening procedure through orthodontic extrusion for treatment of subgingivally fractured teeth; hence, it is more acceptable to the patient.