Publications by authors named "Seung Bae Lee"
Article Synopsis
- The study compared renovated double J stents (DJS) with conventional stents using ureter models to assess their effectiveness for different ureteral diseases.
- Two ureter models were tested: one with stenosis and one without, using various sizes and designs of DJS to evaluate urine flow.
- Results showed that renovated stents had better flow rates in models without stenosis but did not perform significantly better than conventional stents in models with stenosis.
Background: Iatrogenic femoral artery pseudoaneurysm (IFP) incidence is increasing with increase in diagnostic and therapeutic angiography, and so, the less invasive percutaneous thrombin injection (PTI) is the most widely used treatment. Moreover, studies that minimize PTI complications and highlight therapeutic effects are lacking.
Objectives: This study performed in vitro thrombosis modeling of pseudoaneurysms and analyzed thrombosis within and thromboembolism outside the sac during thrombin injection.
Effects of size and shape of the side holes of a double J stent on the ureter fluid flow after stenosis.
Comput Methods Biomech Biomed Engin
September 2024
Article Synopsis
- The study used computational fluid dynamics (CFD) to analyze how different side hole sizes in double J stents (DJS) affect their encrustation in the presence of ureteral stenosis.
- It looked at side holes with varying diameters and how they influenced urine flow rates, shear stress, and wall shear stress (WSS) under different degrees of stenosis (0%, 12%, 88%).
- Results indicated that larger side holes increase flow rates and reduce encrustation, particularly beneficial for patients with urinary stones, especially with a 12% stenosis where flow rates doubled.
Purpose: To evaluate the formation of encrustation on double J stents (DJSs) using artificial urine.
Materials And Methods: In this study, a static urinary system containing artificial urine was created, and a total of 45 DJSs were used to evaluate the formation of encrustation. Three groups of 15 DJSs were tested for 4, 8, or 14 weeks.
Purpose: To assess temporal improvement of prostate image reporting and data system (PIRADS) 3-5 lesion correlation to histopathologic findings from radical prostatectomy (RP) in prostate cancer (PCa).
Materials And Methods: A total of 1481 patients who underwent RP for biopsy-proven PCa between 2015 and 2019 were divided into 14 groups of 100 sequential readings for the evaluation of histopathological correlation with PIRADS readings. Temporal trends of PIRADS distribution and predictive performance for RP pathology were evaluated to assess underlying changes in prostate magnetic resonance imaging (MRI) interpretation by radiologists.
Objective: This study investigates the effects of vesicoureteral reflux (VUR) in the upper and lower urinary tracts with and without ureteral stenosis and with a double J stent (DJS).
Methods: The entire length of the urinary tract with an implanted DJS was modeled. To assess the possibility of VUR, the measured values were used as boundary conditions for the baseline, the maximum cystometric bladder capacity (MCBC) during the filling phase, and maximum vesical pressure during the voiding phase were computed.
Urine flow analysis using double J stents of various sizes in in vitro ureter models.
Int J Numer Method Biomed Eng
February 2020
Article Synopsis
- A double J stent (DJS) is used to relieve urine buildup in the upper urinary tract due to ureteral stenosis, which can lead to renal failure.
- The study tested various sizes of DJSs (from 5Fr to 8Fr) in silicone ureter models without stenosis to evaluate their effectiveness in promoting urine flow.
- Results showed that the smaller 5Fr DJS had higher total flow rates compared to larger sizes, and computational fluid dynamics confirmed that the experimental findings were consistent with the numerical analysis.
Background: Chronic stress contributes to the development of brain disorders, such as neurodegenerative and psychiatric diseases. Oxidative damage is well known as a causative factor for pathogenic process in brain tissues. The aim of this study is to evaluate the neuroprotective effect of a 30% ethanol extract of Aquilariae Lignum (ALE) in repeated stress-induced hippocampal oxidative injury.
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- The ureter allows urine to travel from the kidneys to the bladder, with flow aided by peristalsis and hydrostatic pressure.
- Ureteral diseases and the use of double J stents can disrupt normal urine flow, leading to various shapes of the ureter, like a tube or funnel.
- This study created models of differently shaped ureters to analyze how their shapes and the presence of stents affect urine flow rates and patterns.
To evaluate the effect of naftopidil 75 mg once daily for ureteral double-J (DJ) stent-related discomfort after a ureteroscopic procedure using a multicenter, randomized, double-blinded, placebo-controlled study. 100 patients with indwelled retrograde DJ ureteral stents after ureteroscopic stone removal or retrograde intrarenal surgery (RIRS) were randomized 1:1 to receive either placebo or naftopidil during the stenting period. At the time of stent removal, the Ureteral Stent Symptom Questionnaire (USSQ), the International Prostate Symptom Score and the total amount of used analgesics were reported.
View Article and Find Full Text PDFArticle Synopsis
- * A study explored the impact of side holes in double J stents on urine flow, specifically using models that mimic human anatomy instead of straight ureters.
- * Findings revealed that side holes improved urine flow rates in cases of ureteral stenosis, particularly as the severity of the stenosis increased, although their angular positioning did not influence the flow rates.
Purpose: To evaluate the utility and safety of laparoendoscopic single-site surgery (LESS) in comparison with conventional laparoscopic (CL) surgery for the treatment of upper urinary tract stones.
Material And Methods: Between June 2011 and May 2012, 20 patients with upper urinary tract stones were included in this prospective randomized study. The patients were assigned into the LESS group or CL group in a one-on-one manner using a random table.
Antifungal Activity of Bee Venom and Sweet Bee Venom against Clinically Isolated Candida albicans.
J Pharmacopuncture
March 2016
Objectives: The purpose of this study was to investigate the antifungal effect of bee venom (BV) and sweet bee venom (SBV) against Candida albicans (C. albicans) clinical isolates.
Methods: In this study, BV and SBV were examined for antifungal activities against the Korean Collection for Type Cultures (KCTC) strain and 10 clinical isolates of C.
Objectives: To investigate whether solifenacin intervention leads to any changes in bowel symptoms, and the types of impacts imposed on bowel symptoms in patients with overactive bladder (OAB).
Methods: This prospective, single-arm observational study included 40 adult patients who underwent anticholinergic treatment for OAB. Outcome measures were determined by examining differences in voiding and bowel symptoms, before and after patients commenced anticholinergic therapy.
An inductively-powered wireless integrated neural recording system (WINeR-7) is presented for wireless and battery less neural recording from freely-behaving animal subjects inside a wirelessly-powered standard homecage. The WINeR-7 system employs a novel wide-swing dual slope charge sampling (DSCS) analog front-end (AFE) architecture, which performs amplification, filtering, sampling, and analog-to-time conversion (ATC) with minimal interference and small amount of power. The output of the DSCS-AFE produces a pseudo-digital pulse width modulated (PWM) signal.
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- A double J stent is commonly used for patients with ureteral stenosis or kidney stones, featuring multiple side holes for urine flow.
- Research evaluated the flow rate and patterns around these side holes using models that mimic both curved and straight ureters.
- Results showed that stents with more side holes had higher total flow rates and that the curved ureter model demonstrated more active inflow and outflow compared to straight models, indicating flow occurs even without obstructions.
Article Synopsis
- - Ureteral stenosis can obstruct urine flow and lead to renal failure, with ureteral stents used to alleviate this issue by enabling urine to flow more freely in the upper urinary tract.
- - The insertion of a stent can weaken ureteral peristalsis over time, causing the ureter to appear tubular and curved rather than functioning normally.
- - A study involving 12 stent models (six curved and six straight) highlighted that curved stent designs, which mimic human anatomy, are more effective for simulating and improving urine flow in computational fluid dynamics (CFD) evaluations.
Objective: To compare miniaturized percutaneous nephrolithotomy (mini-PCNL) and retrograde intrarenal surgery (RIRS) in the management of renal stones >10 mm in a single session.
Methods: Seventy patients presenting with renal stones >10 mm were randomized to a mini-PCNL or an RIRS group in a ratio of 1:1. Randomization was performed by a biostatistician and opened to the surgeon at the time of the patient's admission on the day before surgery.
Objectives: To investigate the role of EphA2 in malignant cellular behavior in renal cell carcinoma (RCC) cells and whether FAK/RhoA signaling can act as downstream effectors of EphA2 on RCC cells.
Methods: Expression of EphA2 protein in non-metastatic RCC (Caki-2 and A498), metastatic RCC cells (Caki-1 and ACHN), HEK-293 cells and prostate cancer cells (PC-3 and DU-145; positive controls of EphA2 expression) was evaluated by Western blot. Changes in mRNA or protein expression of EphA2, FAK or membrane-bound RhoA following EphA2, FAK or RhoA small interfering RNA (siRNA) transfection were determined by reverse transcription polymerase chain reaction or Western blot.
Purpose: To investigate surgical outcomes between retrograde intrarenal surgery (RIRS) and percutaneous nephrolithotomy (PNL) groups for a main stone sized 15 to 30 mm and located in the lower-pole calyx.
Materials And Methods: Patients who underwent PNL or RIRS for a main stone sized 15 to 30 mm and located in the lower-pole calyx were retrospectively reviewed. Each patient in the RIRS group was matched to one in the PNL group on the basis of calculated propensity scores by use of age, sex, body mass index, previous treatment history, stone site, maximum stone size, and stone volume.
Background: We developed a sliding-loop technique that narrowed both sides of the parenchyma in a porcine model and compared it with the conventional sliding-clip technique.
Methods: Three pigs (30-40 kg) were reused following another experiment conducted by the same researchers. Bilateral kidneys were harvested within 30 minutes after euthanasia.
Large-Scale Refolding and Enzyme Reaction of Human Preproinsulin for Production of Human Insulin.
J Microbiol Biotechnol
October 2015
Human insulin is composed of 21 amino acids of an A-chain and 30 amino acids of a B-chain. This is the protein hormone that has the role of blood sugar control. When the recombinant human proinsulin is expressed in Escherichia coli, a serious problem is the formation of an inclusion body.
View Article and Find Full Text PDFObjective: To investigate the relationship between low testosterone levels and prostate cancer detection risk in a biopsy population.
Patients And Methods: In all, 681 men who underwent initial 12-core transrectal prostate biopsy at our institution were included in this retrospective study. Patients were divided into groups with low (<300 ng/dL) and normal testosterone levels (≥300 ng/dL).
Objectives: The modified Seoul National University Renal Stone Complexity scoring system (S-ReSC-R) for retrograde intrarenal surgery (RIRS) was developed as a tool to predict stone-free rate (SFR) after RIRS. We externally validated the S-ReSC-R.
Materials And Methods: We retrospectively reviewed 159 patients who underwent RIRS.
Objectives: This study was undertaken to isolate a fibrinolytic enzyme from the snake venom of Gloydius blomhoffii siniticus and to investigate its enzymatic characteristics and hemorrhagic activity as a potential pharmacopuncture agent.
Methods: The fibrinolytic enzyme was isolated by using chromatography, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and fibrin plate assay. The characteristics of the enzyme were investigated using fibrin plate assay, protein hydrolysis analysis, and hemorrhage assay.