Stone-Free Rates of mPCNL, PCNL, and RIRS: A Systematic Review and Network Meta-Analysis

강동혁,조강수,정두용,Won Sik Jeong,Hae Do Jung,Do Kyung Kim,이주용 대한요로생식기감염학회 2022 Urogenital Tract Infection Vol.17 No.1

Purpose: Retrograde intrarenal surgery (RIRS) and percutaneous nephrolithotomy (PCNL) are performed to treat renal stones, and miniature PCNL (mPCNL) is used as an alternative to conventional PCNL. We conducted a systematic review of published studies regarding RIRS, PCNL, and mPCNL and performed network meta-analysis on successful outcome (stone-free) rates. Materials and Methods: The PubMed and EMBASE databases were searched up to December 2020. Data extraction formats were used to extract data on successful outcome rates, study designs, numbers of subjects and characteristics, and methods used to treat renal stones (i.e., RIRS, PCNL, or mPCNL). Results: Data obtained by 25 studies were used to compare the stone-free rates of RIRS, PCNL, and mPCNL; six comparisons of PCNL and mPCNL, seven of mPCNL and RIRS, and 12 of RIRS and PCNL were analyzed. No difference was found between the stone-free rates of PCNL and mPCNL (odds ratio [OR]: 0.96; 95% confidence interval [CI]: 0.51-1.9) by network meta-analysis. However, the stone-free rate of RIRS was lower than that of mPCNL (OR: 0.41; 95% CI: 0.021-0.82) and PCNL (OR: 0.43; 95% CI: 0.22-0.82). Ranking analysis ranked mPCNL as No. 1 and PCNL as No. 2. Conclusions: PCNL and mPCNL had better stone-free rates than RIRS for the treatment of renal stones, but the treatment outcomes of PCNL and mPCNL were no different.

LOx와 Kerosene을 추진제로 하는 1열 핀틀 분사기의 고압 연소성능 특성에 관한 연구

강동혁,김종규,유철성,고영성 항공우주시스템공학회 2022 항공우주시스템공학회지 Vol.16 No.5

The pintle injector has many advantages in the key characteristics of a liquid rocket engine, such as combustion stability, combustion efficiency, and wide range of comprehensive thrust control, design and manufacture, and test fired under supercritical conditions. The pintle injector is manufactured with a rectangular, single-row orifice for thrust control and production considerations. In order to verify the combustion performance of the pintle injector and its potential as a commercial injector, the combustion characteristics were analyzed by varying the TMR (Total Momentum Ratio) and BF (Blockage Factor). The result of the hot firing test showed that the heat flux increased as TMR increased, and it confirmed that the characteristic velocity efficiency was more affected by BF than TMR. Suppose a single-row pintle injector with efficiency characteristics insensitive to changes in TMR can achieve high efficiency at low fuel differential pressure conditions. In that case, the variable pintle injector’s design flexibility can be increase.

Silencing Histone Deacetylase 7 Alleviates Transforming Growth Factor-β1-Induced Profibrotic Responses in Fibroblasts Derived from Peyronie’s Plaque

강동혁,윤국남,최민지,송강문,Kalyan Ghatak,Nguyen Nhat Minh,권미혜,성도환,류지간,서준규 대한남성과학회 2018 The World Journal of Men's Health Vol.36 No.2

Purpose: Epigenetic modifications, such as histone acetylation/deacetylation and DNA methylation, play a crucial role in thepathogenesis of inflammatory disorders and fibrotic diseases. The aim of this study was to study the differential gene expressionof histone deacetylases (HDACs) in fibroblasts isolated from plaque tissue of Peyronie’s disease (PD) or normal tunicaalbuginea (TA) and to examine the anti-fibrotic effect of small interfering RNA (siRNA)-mediated silencing of HDAC7 in fibroblastsderived from human PD plaque. Materials and Methods: For differential gene expression study, we performed reverse-transcriptase polymerase chain reactionfor HDAC isoforms (1–11) in fibroblasts isolated from PD plaque or normal TA. Fibroblasts isolated from PD plaque were pretreatedwith HDAC7 siRNA (100 pmol) and then stimulated with transforming growth factor-β1 (TGF-β1, 10 ng/mL). Proteinwas extracted from treated fibroblasts for Western blotting. We also performed immunocytochemistry to detect the expressionof extracellular matrix proteins and to examine the effect of HDAC2 siRNA on the TGF-β1-induced nuclear translocation ofSmad2/3 and myofibroblastic differentiation. Results: The mRNA expression of HDAC2, 3, 4, 5, 7, 8, 10, and 11 was higher in fibroblasts isolated from PD plaque than infibroblasts isolated from normal TA tissue. Knockdown of HDAC7 in PD fibroblasts inhibited TGF-β1-induced nuclear shuttleof Smad2 and Smad3, transdifferentiation of fibroblasts into myofibroblasts, and abrogated TGF-β1-induced production ofextracellular matrix protein. Conclusions: These findings suggest that specific inhibition of HDAC7 with RNA interference may represent a promising epigenetictherapy for PD.

Efficacy and Safety of Tadalafil 5 mg Administered Once Daily in Korean Men with Erectile Dysfunction: A Prospective, Multicenter Study

강동혁,이주용,박성열,문홍상,정태융,유탁근,최홍용,박해영,이춘용,이승욱 대한비뇨의학회 2010 Investigative and Clinical Urology Vol.51 No.9

Purpose: The aim of this study was to evaluate the efficacy of a daily dose of tadalafil 5 mg as well as its safety for the cardiovascular system in men with erectile dysfunction. Materials and Methods: This study included a total of 162 men who were administered a daily dose of tadalafil 5 mg between April and December of 2009. A total of 127 men completed the 8-week clinical trial. The International Index of Erectile Function (IIEF)-5, blood pressure, and heart rate were measured before treatment with tadalafil (V1) and 4 (V2) and 8 weeks (V3) after treatment with tadalafil. Adverse effects were assessed at V1, V2, and V3. In cases in which the International Prostate Symptom Score (IPSS) was ≥8 at V1, maximal flow rate (Qmax) and postvoid residual volume (PVR) were measured. Results: The IIEF-5 values were 11.25±3.18, 14.56±3.79, and 16.91±3.56 at V1, V2, and V3, respectively, with significant improvement (V1 vs. V2, p<0.001; V1 vs. V3, p<0.001). The IPSS values were 10.59±5.56, 9.07±6.06, and 8.15±6.10 at V1, V2, and V3, respectively, and the differences were statistically significant (V1 vs. V2, p<0.001; V1 vs. V3, p<0.001). There were no significant differences in blood pressure or heart rate. Adverse effects were observed in 7 men (5.51%) at V2 and in 5 men (3.94%) at V3. Conclusions: Tadalafil 5 mg administered once-a-day may be effective in improving erectile function. Adverse effects on the cardiovascular system may be minimal. In addition, it is believed that this may also be effective in improving voiding symptoms. Purpose: The aim of this study was to evaluate the efficacy of a daily dose of tadalafil 5 mg as well as its safety for the cardiovascular system in men with erectile dysfunction. Materials and Methods: This study included a total of 162 men who were administered a daily dose of tadalafil 5 mg between April and December of 2009. A total of 127 men completed the 8-week clinical trial. The International Index of Erectile Function (IIEF)-5, blood pressure, and heart rate were measured before treatment with tadalafil (V1) and 4 (V2) and 8 weeks (V3) after treatment with tadalafil. Adverse effects were assessed at V1, V2, and V3. In cases in which the International Prostate Symptom Score (IPSS) was ≥8 at V1, maximal flow rate (Qmax) and postvoid residual volume (PVR) were measured. Results: The IIEF-5 values were 11.25±3.18, 14.56±3.79, and 16.91±3.56 at V1, V2, and V3, respectively, with significant improvement (V1 vs. V2, p<0.001; V1 vs. V3, p<0.001). The IPSS values were 10.59±5.56, 9.07±6.06, and 8.15±6.10 at V1, V2, and V3, respectively, and the differences were statistically significant (V1 vs. V2, p<0.001; V1 vs. V3, p<0.001). There were no significant differences in blood pressure or heart rate. Adverse effects were observed in 7 men (5.51%) at V2 and in 5 men (3.94%) at V3. Conclusions: Tadalafil 5 mg administered once-a-day may be effective in improving erectile function. Adverse effects on the cardiovascular system may be minimal. In addition, it is believed that this may also be effective in improving voiding symptoms.

Analysis of Prescriptions of Alpha-Blockers and Phosphodiesterase 5 Inhibitors from the Urology Department and Other Departments

강동혁,이주용,정재훈,조희주,조정만,문홍상,김용태,유탁근,최홍용,박해영,이승욱 대한배뇨장애요실금학회 2011 International Neurourology Journal Vol.15 No.4

Purpose: We analyzed the prescriptions of alpha-blockers and phosphodiesterase 5 inhibitors (PDE5Is) in the urology department as well as in other departments of the general hospital. Methods: We investigated the frequency of prescription of alpha-blockers and PDE5Is from 3 general hospitals from January 1, 2007 to December 31, 2009. For alpha-blockers, data were collected from patients to whom alpha-blockers were prescribed from among patients recorded as having benign prostatic hyperplasia according to the 5th Korean Standard Classification of Diseases. For PDE5Is, data were collected from patients to whom PDE5Is were prescribed by the urology department and by other departments. Alpha-blockers were classified into tamsulosin, alfuzosin, doxazosin, and terazosin, whereas PDE5Is were classified into sildenafil, tadalafil, vardenafil, udenafil, and mirodenafil. Results: Alpha-blockers were prescribed to 11,436 patients in total over 3 years, and the total frequency of prescriptions was 68,565. Among other departments, the nephrology department had the highest frequency of prescription of 3,225 (4.7%), followed by the cardiology (3,101, 4.5%), neurology (2,576, 3.8%), endocrinology (2,400, 3.5%), pulmonology (1,102, 1.6%), and family medicine (915, 1.3%) departments in order. PDE5Is were prescribed to 2,854 patients in total over 3 years, and the total frequency of prescriptions was 10,558. The prescription frequency from the urology department was 4,900 (46.4%). Among other departments, the endocrinology department showed the highest prescription frequency of 3,488 (33.0%), followed by the neurology (542, 5.1%), cardiology (467, 4.4%), and family medicine (407, 3.9%) departments in order. Conclusions: A high percentage of prescriptions of alpha-blockers and PDE5Is were from other departments. For more specialized medical care by urologists is required in the treatment of lower urinary tract symptoms and erectile dysfunction.

실물형 연소기 재생냉각 연소시험을 위한 설비개선 및 연소기 장착 수류시험

강동혁,임병직,이광진,한영민,최환석 한국항공우주학회 2007 한국항공우주학회 학술발표회 논문집 Vol.- No.-

Al₂O₃-coated Macro 3D Porous Mulberry Paper as a Zinc Anode for Highly Reversible Aqueous Zinc Metal Batteries

강동혁,현종찬,하손,박지민,윤영수 한국고분자학회 2021 한국고분자학회 학술대회 연구논문 초록집 Vol.46 No.1

Research interest in aqueous rechargeable batteries (ARBs) has increased in recent years, because ARBs have many advantages such as high kinetic performances, environmental benignity, and nonflammable aqueous electrolytes. Among of ARBs, one of the most promising candidates is aqueous zinc batteries (AZBs) owing to high theoretical capacity, low redox potential, and excellent chemical stability. However, the AZBs suffers from poor electrochemical performances of zinc metal anode (ZMA) such as low CE originating from side reactions and dendritic metal growth during cycling process. Although mildly acidic aqueous electrolytes are partly effective for the issues, the ZMA still suffers from the poor electrochemical performances. In this study, we propose a surface-modified carbon-based electrode material to guide a selective zinc metal deposition with no side reaction. Hence, high-performance AZBs were achieved by introducing the surface-modified carbon-based electrode materials for ZMA.

The Possibilities as a Prediction Tool for Cancer Research of Big Data: Comparison of Incidence Rate of Korean Major Male and Urologic Cancers and Trend Scores

강동혁,조강수,함원식,최영득,이주용 대한비뇨기종양학회 2015 대한비뇨기종양학회지 Vol.13 No.1

Purpose: To examine the trend, and investigated the possibilities as a prediction tool by choosing the trend score about male and urologic cancers have the high incidence rate. Materials and Methods: We selected 5 major male and 3 major urologic cancers for past 3 years (from 2010 to 2012) and examined the incidence rate, and using Naver and Google trend, the rate of cancer incidence was compared with the trend score during the same period. Results: From 2010 to 2012, the greatest occurrence of the cancer to males was the stomach cancer, followed by colon, lung, liver, and prostate cancer. In the urologic field, the prostate cancer was the first one, followed by kidney and bladder cancer. In 2010 to 2012, the Naver trend score was 32 for stomach and colon cancers, 31 for lung cancers, 20 for liver cancers, and 19 for prostate cancers, which index were corresponded with the order of incidence rate. Though the Google trend score for prostate cancer was not found, the average was 9 for stomach cancer, 8 for colon cancer, 6 for lung cancer, 4 for liver cancer, which index were corresponded with the order of incidence rate. In 2013 and 2014, the figure of prostate cancer was grown and exceeded liver cancer. Conclusions: In the trend score, the index of the prostate cancer shows continuing increase, and, from the results, urologists should recognize the importance of the study on the prostate cancer such as management, prevention, and treatment of the prostate cancer.

Ureteral stenting can be a negative predictor for successful outcome following shock wave lithotripsy in patients with ureteral stones

강동혁,조강수,함원식,정두용,권종규,최영득,이주용 대한비뇨의학회 2016 Investigative and Clinical Urology Vol.57 No.6

Purpose: To evaluate ureteral stenting as a negative predictive factor influencing ureteral stone clearance and to estimate the probability of one-session success in shock wave lithotripsy (SWL) patients with a ureteral stone. Materials and Methods: We retrospectively reviewed the medical records of 1,651 patients who underwent their first SWL. Among these patients, 680 had a ureteral stone measuring 4–20 mm and were thus eligible for our study. The 57 patients who underwent ureteral stenting during SWL were identified. Maximal stone length (MSL), mean stone density (MSD), skin-to-stone distance (SSD), and stone heterogeneity index (SHI) were determined by pre-SWL noncontrast computed tomography. Results: After propensity score matching, 399 patients were extracted from the total patient cohort. There were no significant differences between stenting and stentless groups after matching, except for a higher one-session success rate in the stentless group (78.6% vs. 49.1%, p=0.026). In multivariate analysis, shorter MSL, lower MSD, higher SHI, and absence of a stent were positive predictors for one-session success in patients who underwent SWL. Using cutoff values of MSL and MSD obtained from receiver operator curve analysis, in patients with a lower MSD (≤784 HU), the success rate was lower in those with a stent (61.1%) than in those without (83.5%) (p=0.001). However, in patients with a higher MSL (>10 mm), the success rate was lower in those with a stent (23.6%) than in those without (52.2%) (p=0.002). Conclusions: Ureteral stenting during SWL was a negative predictor of one-session success in patients with a ureteral stone.

극저온 액화가스 누출에 의한 선체 구조용 강재의 샤르피 충격성능에 관한 연구

강동혁,김정현,김슬기,김태욱,박두환,박기범,이제명 한국산업융합학회 2023 한국산업융합학회 논문집 Vol.26 No.2

Environmental regulations are being strengthened worldwide to solve global warming. For this reason, interest in eco-friendly gas fuels such as LNG and hydrogen is continuously increasing. However, when adopting eco-friendly gas fuel, liquefying at a cryogenic temperature is essential to ensure economic feasibility in storage and transportation. Although austenitic stainless steel is typically applied to store cryogenic liquefied gas, structural steel can experience sudden heat shrinkage in the case of leakage in the loading and unloading process of LNG. In severe cases, the phase of the steel may change, so care is required. This study conducted Charpy impact tests on steel material in nine different temperature ranges, from room to cryogenic temperatures, to analyze the effects of cryogenic liquefied gas leaks. As a result of the study, it was not easy to find variations in ductile to brittle transition temperature (DBTT) due to the leakage of cryogenic liquefied gas. Still, the overall impact toughness tended to decrease, and these results were verified through fracture surface analysis. In summary, brittle fracture of the steel plate may occur when a secondary load is applied to steel for hull structural use exposed to a cryogenic environment of -40 ℃ or lower. Therefore, it needs to be considered in the ship design and operating conditions.