MOCVD법에 의한 광 통신용 1.55㎛ PBH-DFB 레이저 다이오드 제작

오환술,김중연,전현성,강명구 건국대학교 산업기술연구원 1997 건국기술연구논문지 Vol.22 No.-

DC-PBHDFB LD operating at 1.55㎛ were fabricated by 3-step MOCVD process. The first-order grating with 2370Å period and 700Å etching depth was formed by holographic lithography and wet etching. Fabricated DCPBH-DFB LD operates in single longitudinal mode with side-mode suppression of more than 35dB and the lasing wavelength of 1.547㎛ at room temperature and 5mW, and the lasing threshold current and the slope efficiency were 15.6mA and 0.15mW/mA, respectively. The characteristic temperature of threshold current(To) and the temperature dependence of the lasing wavelength were obtained 57.3K and 1.0Å/℃ from the DFB laser between 20℃ and 70℃, respectively.

Oncological and functional outcomes following robot-assisted laparoscopic radical prostatectomy at a single institution: a minimum 5-year follow-up

Kang, Jun-Koo,Chung, Jae-Wook,Chun, So Young,Ha, Yun-Sok,Choi, Seock Hwan,Lee, Jun Nyung,Kim, Bum Soo,Yoon, Ghil Suk,Kim, Hyun Tae,Kim, Tae-Hwan,Kwon, Tae Gyun Yeungnam University College of Medicine 2018 Yeungnam University Journal of Medicine Vol.35 No.2

Background: To evaluate mid-term oncological and functional outcomes in patients with prostate cancer treated by robot-assisted laparoscopic radical prostatectomy (RALP) at our institution. Methods: We retrospectively reviewed the medical records of 128 patients with prostate cancer who underwent RALP at our institution between February 2008 and April 2010. All patients enrolled in this study were followed up for at least 5 years. We analyzed biochemical recurrence (BCR)-free survival using a Kaplan-Meier survival curve analysis and predictive factors for BCR using multivariate Cox regression analysis. Continence recovery rate, defined as no use of urinary pads, was also evaluated. Results: Based on the D'Amico risk classification, there were 30 low-risk patients (23.4%), 47 intermediaterisk patients (38.8%), and 51 high-risk patients (39.8%), preoperatively. Based on pathological findings, 50.0% of patients (64/128) showed non-organ confined disease (${\geq}T3a$) and 26.6% (34/128) had high grade disease (Gleason score ${\geq}8$). During a median follow-up period of 71 months (range, 66-78 months), the frequency of BCR was 33.6% (43/128) and the median BCR-free survival was 65.9 (0.4-88.0) months. Multivariate Cox regression analysis revealed that high grade disease (Gleason score ${\geq}8$) was an independent predictor for BCR (hazard ratio=4.180, 95% confidence interval=1.02-17.12, p=0.047). In addition, a majority of patients remained continent following the RALP procedure, without the need for additional intervention for post-prostatectomy incontinence. Conclusion: Our study demonstrated acceptable outcomes following an initial RALP procedure, despite 50% of the patients investigated demonstrating high-risk features associated with non-organ confined disease.

The Chloroform Fraction of Carpinus tschonoskii Leaves Inhibits the Production of Inflammatory Mediators in HaCaT Keratinocytes and RAW264.7 Macrophages

Kang, Gyeoung-Jin,Kang, Na-Jin,Han, Sang-Chul,Koo, Dong-Hwan,Kang, Hee-Kyoung,Yoo, Byoung-Sam,Yoo, Eun-Sook Korean Society of ToxicologyKorea Environmental Mu 2012 Toxicological Research Vol.28 No.4

Inflammation is the immune system's response to infection and injury-related disorders, and is related to pro-inflammatory factors (NO, $PGE_2$, cytokines, etc.) produced by inflammatory cells. Atopic dermatitis (AD) is a representative inflammatory skin disease that is characterized by increasing serum levels of inflammatory chemokines, including macrophage-derived chemokine (MDC). Carpinus tschonoskii is a member of the genus Carpinus. We investigated the anti-inflammatory activity of C. tschonoskii by studying the effects of various solvent fractions prepared from its leaves on inflammatory mediators in HaCaT and RAW264.7 cells. We found that the chloroform fraction of C. tschonoskii inhibited MDC at both the protein and mRNA levels in HaCaT cells, acting via the inhibition of STAT1 in the IFN-${\gamma}$ signaling pathway. In addition, the chloroform fraction significantly suppressed the expression of inflammatory factors induced by lipopolysaccharide stimulation, except COX-2 and TNF-${\alpha}$. These results suggest that the chloroform fraction of C. tschonoskii leaves may include a component with potential anti-inflammatory activity.

Genotoxicity of Recombinant Human Basic Fibroblast Growth Factor

Kyung Koo Kang,Dong Hwan Kim,Hyun Cho,Byoung Ok Ahn,Soo Hyung Kang,Won Bae Kim 한국독성학회 1999 Toxicological Research Vol.15 No.3

A new recombinant human basic fibroblast growth factor (rh-bFGF) was investigated for its genotoxic potential by using the battery of tests recommended by toxicological regulatory guidelines for new drugs. These tests were the Ames test for determination of bacterial gene mutation, in vitro chromosome aberration test and micronucleus test for evaluation of structural and numerical chromosomal aberrations. In the Ames test 6 different doses of rh-bFGF, in the range of 0.003~1.0 mg/plate, did not induce his+ revertants, with or without metabolic activation system. In the cytogenetic test on chinese hamster cells, rh-bFGF did not cause chromosomal aberrations at the concentration of 0.007~0.2 mg/ml either in the presence or absence of metabolic activation. Furthermore, in the micronucleus test using three doses, 30, 6.0 and 1.2 mg/kg, rh-bFGF did not show any positive response. These results suggest that rh-bFGF has no mutagenic or clastogenic effects, and does not interfere with cell division. It is, therefore, concluded that rh-bFGF has no genotoxic potential.

Ankle Deformity Secondary to Acquired Fibular Segmental Defect in Children

Soo Hwan Kang,Seung Koo Rhee,Seok Whan Song,Jin Wha Chung,Yoon Chung Kim,Kyung Hwan Suhl 대한정형외과학회 2010 Clinics in Orthopedic Surgery Vol.2 No.3

Background: The authors report the long-term effect of acquired pseudoarthrosis of the fi bula on ankle development in childrenduring skeletal growth, and the results of a long-term follow-up of Langenskiold’s supramalleolar synostosis to correct an ankledeformity induced by an acquired fi bular segmental defect in children. Methods: Since 1980, 19 children with acquired pseudoarthrosis of the fi bula were treated and followed up for an average of 11years. Pseudoarthrosis was the result of a fi bulectomy for tumor surgery, osteomyelitis of the fi bula and traumatic segmental lossof the fi bula in 10, 6, and 3 cases, respectively. Initially, a Langenskiold’s operation (in 4 cases) and fusion of the lateral malleolusto the distal tibial epiphysis (in 1 case) were performed, whereas only skeletal growth was monitored in the other 14 cases. Aftera mean follow-up of 11 years, the valgus deformity and external tibial torsion of the ankle joint associated with proximal migrationof the lateral malleolus needed to be treated with a supramallolar osteotomy in 12 cases (63%). These ankle deformities wereevaluated using the serial radiographs and limb length scintigraphs. Results: In all cases, early closure of the lateral part of the distal tibial physis, upward migration of the lateral malleolus, unstablevalgus deformity and external tibial torsion of the ankle joint developed during a mean follow-up of 11 years (range, 5 to 21 years). The mean valgus deformity and external tibial torsion of the ankle at the fi nal follow-up were 15.2° (range, 5° to 35°) and 10° (range,5° to 12°), respectively. In 12 cases (12/19, 63%), a supramalleolar corrective osteotomy was performed but three children had arecurrence requiring an additional supramalleolar corrective osteotomy 2-4 times. Conclusions: A valgus deformity and external tibial torsion are inevitable after acquired pseudoarthrosis of the fi bula in children. Both Langenskiöld supramalleolar synostosis to prevent these ankle deformities and supramalleolar corrective osteotomy to correctthem in children are effective initially. However, both procedures can not maintain the permanent ankle stability during skeletalmaturity. Therefore any type of prophylactic surgery should be carried out before epiphyseal closure of the distal tibia occurs, butthe possibility of a recurrence of the ankle deformities and the need for fi nal corrective surgery after skeletal maturity should beconsidered

Angiogenic effects of recombinant thymosin β4 in a mouse hindlimb ischemia model

Jun-Hwan Moon,Jung-Won Lee,Jong-Koo Kang 충북대학교 동물의학연구소 2014 Journal of Biomedical and Translational Research Vol.15 No.4

Recombinant thymosin β4 (rTβ4) has been reported to migrate and promote vascularization, wound-healing, and hair growth in a mouse hindlimb ischemia model of peripheral vascular disease. C57BL/6 mice (11-weeks-old) were anesthetized and an ischemic model was made by cutting the right aorta femoralis. The ischemic group was intraperitoneally administered with saline (300 μL/mouse) and the muscular administration group received rTβ4 (150 μg in 300 μL of saline) or rTβ4 (150 μg in 300 μL saline) to the abdominal cavity at 3-day intervals for 21 days. Myoatrophy of the ischemic group was observed compared to the normal control group. Generation of adjacent vessels was carried out in the rTβ4 administration group compared to the ischemic group. The biopsy results showed significant fibrosis around the muscular undersurface and perimysium in the musculus quadriceps femoris of the ischemic group, whereas partial fibrosis was observed in the perimysium and endomysium in the rTβ4 administration group. Immunostaining indicated that expression levels of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor-1 (VEGF-1), and endothelial nitric oxide synthase (eNOS) in the rTβ4 group were higher than those of the ischemic group. Western blotting showed that expression levels of HIF-1α, VEGF-1, and eNOS in the rTβ4 group were higher than those of the ischemic group. In conclusion, rTβ4 increases expression levels of HIF-1α, VEGF-1, and eNOS, resulting in angiogenesis.

Oncological and functional outcomes following robot-assisted laparoscopic radical prostatectomy at a single institution: a minimum 5-year follow-up

( Jun-koo Kang ),( Jae-wook Chung ),( So Young Chun ),( Yun-sok Ha ),( Seock Hwan Choi ),( Jun Nyung Lee ),( Bum Soo Kim ),( Ghil Suk Yoon ),( Hyun Tae Kim ),( Tae-hwan Kim ),( Tae Gyun Kwon ) 영남대학교 의과대학 2018 Yeungnam University Journal of Medicine Vol.35 No.2

Background: To evaluate mid-term oncological and functional outcomes in patients with prostate cancer treated by robot-assisted laparoscopic radical prostatectomy (RALP) at our institution. Methods: We retrospectively reviewed the medical records of 128 patients with prostate cancer who underwent RALP at our institution between February 2008 and April 2010. All patients enrolled in this study were followed up for at least 5 years. We analyzed biochemical recurrence (BCR)-free survival using a Kaplan-Meier survival curve analysis and predictive factors for BCR using multivariate Cox regression analysis. Continence recovery rate, defined as no use of urinary pads, was also evaluated. Results: Based on the D’Amico risk classification, there were 30 low-risk patients (23.4%), 47 intermediaterisk patients (38.8%), and 51 high-risk patients (39.8%), preoperatively. Based on pathological findings, 50.0% of patients (64/128) showed non-organ confined disease (≥T3a) and 26.6% (34/128) had high grade disease (Gleason score ≥8). During a median follow-up period of 71 months (range, 66-78 months), the frequency of BCR was 33.6% (43/128) and the median BCR-free survival was 65.9 (0.4-88.0) months. Multivariate Cox regression analysis revealed that high grade disease (Gleason score ≥8) was an independent predictor for BCR (hazard ratio=4.180, 95% confidence interval=1.02-17.12, p=0.047). In addition, a majority of patients remained continent following the RALP procedure, without the need for additional intervention for post-prostatectomy incontinence. Conclusion: Our study demonstrated acceptable outcomes following an initial RALP procedure, despite 50% of the patients investigated demonstrating high-risk features associated with non-organ confined disease.

Dieckol, a Component of Ecklonia cava, Suppresses the Production of MDC/CCL22 via Down-Regulating STAT1 Pathway in Interferon-γ Stimulated HaCaT Human Keratinocytes

( Na Jin Kang ),( Dong Hwan Koo ),( Gyeoung Jin Kang ),( Sang Chul Han ),( Bang Won Lee ),( Young Sang Koh ),( Jin Won Hyun ),( Nam Ho Lee ),( Mi Hee Ko ),( Hee Kyoung Kang ),( Eun Sook Yoo ) 한국응용약물학회 2015 Biomolecules & Therapeutics(구 응용약물학회지) Vol.23 No.3

Macrophage-derived chemokine, C-C motif chemokine 22 (MDC/CCL22), is one of the inflammatory chemokines that controls the movement of monocytes, monocyte-derived dendritic cells, and natural killer cells. Serum and skin MDC/CCL22 levels are elevated in atopic dermatitis, which suggests that the chemokines produced from keratinocytes are responsible for attracting inflammatory lymphocytes to the skin. A major signaling pathway in the interferon-γ (IFN-γ)-stimulated inflammation response involves the signal transducers and activators of transcription 1 (STAT1). In the present study, we investigated the anti-inflammatory effect of dieckol and its possible action mechanisms in the category of skin inflammation including atopic dermatitis. Dieckol inhibited MDC/CCL22 production induced by IFN-γ (10 ng/mL) in a dose dependent manner. Dieckol (5 and 10 μM) suppressed the phosphorylation and the nuclear translocation of STAT1. These results suggest that dieckol exhibits anti-inflammatory effect via the down-regulation of STAT1 activation.

블루투스 스캐터넷의 형태에 따른 성능 분석

강형구(Hyung-Koo Kang),강석진(Suk-Jin Kang),차정근(Jung-Keun Cha),고진환(Jin-Hwan Koh) 한국정보과학회 2002 한국정보과학회 학술발표논문집 Vol.29 No.2Ⅲ

Bluetooth는 기기들간에 고정된 제어 장치를 갖지 않고 각각의 이동 기기가 스스로 piconet이라는 불리는 네트워크를 구성하게 되고, 이 piconet을 확장하여 scatternet을 구성하게 된다. 이 scatternet의 형태는 Bluetooth 망 전체 성능에 큰 영향을 미치게 되는데, 본 논문에서는 지금까지 제시된 scatternet의 구성 방법들을 알아보고, scatterne을 구성하기 위해 piconet간에 공유되는 bridge 노드의 숫자를 2개까지 늘려서 원활한 통신과 안정적인 망 구성을 위한 방안을 제시한다. 또한, 성능 분석을 위하여 Bluetooth 전문 시뮬레이터인 IBM의 BlueHoc을 사용하여 bridge 노드수와 scatternet을 구성하는 piconet수의 변화에 따른 scatternet의 성능을 모의 실험을 통해 측정하여 보았다.

The Chloroform Fraction of Carpinus tschonoskii Leaves Inhibits the Production of Inflammatory Mediators in HaCaT Keratinocytes and RAW264.7 Macrophages

Gyeoung-Jin Kang,Na-Jin Kang,Sang-Chul Han,Dong-Hwan Koo,Hee-Kyoung Kang,Byoung-Sam Yoo,Eun-Sook Yoo 한국독성학회 2012 Toxicological Research Vol.28 No.4

Inflammation is the immune system’s response to infection and injury-related disorders, and is related to pro-inflammatory factors (NO, PGE₂, cytokines, etc.) produced by inflammatory cells. Atopic dermatitis (AD) is a representative inflammatory skin disease that is characterized by increasing serum levels of inflammatory chemokines, including macrophage-derived chemokine (MDC). Carpinus tschonoskii is a member of the genus Carpinus. We investigated the anti-inflammatory activity of C. tschonoskii by studying the effects of various solvent fractions prepared from its leaves on inflammatory mediators in HaCaT and RAW264.7 cells. We found that the chloroform fraction of C. tschonoskii inhibited MDC at both the protein and mRNA levels in HaCaT cells, acting via the inhibition of STAT1 in the IFN-γ signaling pathway. In addition, the chloroform fraction significantly suppressed the expression of inflammatory factors induced by lipopolysaccharide stimulation, except COX-2 and TNF-α. These results suggest that the chloroform fraction of C. tschonoskii leaves may include a component with potential anti-inflammatory activity.