Publications by authors named "Sang Don Lee"

128 Publications

Penile circumference and stretched penile length in prepubertal children: A retrospective, single-center pilot study.

Investig Clin Urol 2021 May;62(3):324-330

Department of Urology, Pusan National University Yangsan Hospital, Yangsan, Korea.

Purpose: To determine references for penile circumference according to age in prepubertal children and whether this measurement can be used as a basic penile parameter along with stretched penile length in prepubertal children.

Materials And Methods: A total of 750 children (mean age, 4.2±3.4 years) aged under 14 years without penile problems were enrolled in this study. Children with penile or testicular abnormalities were excluded. All data were gathered at the outpatient clinic by a single pediatric urologist from July 2017 to April 2020. Penile parameters (baseline and stretched penile length, penile circumference) and testicular volumes were measured by using an elastic ruler and a Prader orchidometer, respectively.

Results: Mean baseline and stretched penile lengths were 3.0±1.0 cm and 4.2±1.0 cm, respectively. The mean penile circumference was 4.2±0.9 cm. The stretched penile length was similar to penile circumference (p=0.425). This similarity was found for each age group except for the 0-1-year-old and 3-4-year-old age groups (p=0.001 and p=0.034, respectively). As children grow into adolescence, stretched penile length increases significantly compared to penile circumference.

Conclusions: Penile circumference increased with age like stretched penile length and testicular volume in prepubertal children. Stretched penile length and penile circumference were found to be similar. This study can be used as a basic reference for penile circumference values in prepubertal children.
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http://dx.doi.org/10.4111/icu.20200495DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8100007PMC
May 2021

Concealed index for concealed penis in prepubertal children.

Investig Clin Urol 2021 Mar;62(2):217-223

Department of Urology, Pusan National University Yangsan Hospital, Yangsan, Korea.

Purpose: The concealed penis (CP) is a congenital or acquired genital anomaly that requires surgical correction. To construct an objective CP severity index, we compared the penile parameters of a CP with a normal penis (NP) and postoperative outcomes of CP patients.

Materials And Methods: In this retrospective study, 391 boys under 14 years who visited our hospital between September 2017 and February 2020 were included. Among these boys, 105 patients had a CP and 286 boys had a NP without CP. The stretched penile length (SPL), penile circumference (PC), and penile length above baseline skin level (BPL) were measured using a ruler (cm), and the testicular volume was measured using an orchidometer (mL). We defined the concealed index according to SPL (CIs) as BPL/SPL and the concealed index according to circumference (CIc) as BPL/PC. A repair of the CP was performed in the CP patients. All parameters were measured before surgery and after three months.

Results: The CP had significantly shorter SPL and BPL, and smaller CIs, and CIc than the NP. The cutoff values for the CIs and CIc were 0.68 and 0.58, respectively (sensitivity 86.7% and 86.7%; specificity 65.0% and 88.5%, respectively). After repair of the CP, all penile parameters were significantly improved.

Conclusions: The CIs and CIc are useful and objective parameters for checking the severity of CP, and evaluating the postoperative outcome of CP repair. We newly introduced cutoff values for the CIs (0.68) and CIc (0.58) for diagnosing and evaluating CP repair.
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http://dx.doi.org/10.4111/icu.20200401DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7940854PMC
March 2021

Pediatric laparoscopic pyeloplasty of pelvic ectopic kidney with UPJO - A case report.

Urol Case Rep 2021 Jan 23;34:101507. Epub 2020 Nov 23.

Department of Urology, Pusan National University Yangsan Hospital, Yangsan, South Korea.

Prevalence of pelvic ectopic kidney with obstruction is not common. Associated anomalies may produce technical difficulties and surgical challenges in treatment. Diagnostic tools such as USG KUB, renal scintigraphic studies (DMSA, DTPA), MRI, and preoperative RGP are very informative examinations to properly decide the timing of the operation and method of it. The patient was under close surveillance from the detection of antenatal hydronephrosis until the development of UPJ obstruction. Herein, we report the case of a patient with this anomaly who successfully underwent laparoscopic reconstruction.
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http://dx.doi.org/10.1016/j.eucr.2020.101507DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7701345PMC
January 2021

Risk factors for fistula recurrence after urethrocutaneous fistulectomy in children with hypospadias.

Turk J Urol 2020 Nov 30. Epub 2020 Nov 30.

Department of Urology, Pusan National University Yangsan Hospital, Yangsan, Korea.

Objective: This study aimed to investigate the risk factors of fistula recurrence after primary urethrocutaneous fistulectomy in children with hypospadias.

Material And Methods: The study included 63 children who underwent fistulectomy for urethrocutaneous fistula (UCFs) that occurred after urethroplasty for hypospadias, between February 2009 and December 2018. The patients were divided into 2 groups: successful group 1 and failed group 2. For data analysis, we included the demographics of the patients, the details of the previous urethroplasty (the type of hypospadias and the location of the meatus after complete chordectomy), the presence of meatal stenosis or urethral stricture after urethroplasty, and the size of the UCFs. The Student t-test and the chi-square test were performed to analyze the data using the Statistical Package for Social Sciences software.

Results: The overall success rate of primary urethrocutaneous fistulectomy was 81.0% (51/63 children). The most common location of a secondary fistula was the penoscrotal area 5 (41.6%). There were no statistically significant differences in age (p=0.501), weight (p=0.063), body mass index (p=0.924), history of low birth weight (p=0.454), and history of prematurity (p=0.381). The type of hypospadias (p=0.007) and urethral defect length (p=0.021) were identified as independent risk factors for failed urethrocutaneous fistulectomy. There were no statistically significant differences in meatal stenosis (p=0.431), postoperative stricture (p=0.587), fistula location (p=0.173), multiplicity (p=0.588), and fistula size (p=0.530).

Conclusion: The type of hypospadias and the length of the urethral defect are the significant risk factors for secondary fistula recurrence after primary urethrocutaneous fistulectomy.
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http://dx.doi.org/10.5152/tud.2020.20323DOI Listing
November 2020

Korean Clinical Practice Guideline for the Diagnosis and Treatment of Insomnia in Adults.

Psychiatry Investig 2020 Nov 18;17(11):1048-1059. Epub 2020 Nov 18.

Department of Psychiatry, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.

Objective: We aim to present a clinical guideline for the diagnosis and treatment of insomnia in adults by reviewing and integrating existing clinical guidelines. The purpose of this guideline is to assist clinicians who perform evidence-based insomnia treatment.

Methods: We selected literature that may be appropriate for use in guideline development from evidence-based practice guidelines that have been issued by an academic or governmental institution within the last five years. The core question of this guideline was made in sentence form including Patient/Problem, Intervention, Comparison, Outcome (PICO) elements. After searching PubMed, EMBASE, and medical guideline issuing agencies, three guidelines were judged to be the most appropriately reviewed, up-to-date, and from trusted sources.

Results: The Appraisal of Guidelines for Research and Evaluation (AGREE) II tool was used to evaluate the quality of the three clinical guidelines. The final outcome of the guideline development process is a total of 15 recommendations that report the strength of the recommendation, the quality of evidence, a summary of content, and considerations in applying the recommendation.

Conclusion: It is vital for clinical guidelines for insomnia to be developed and continually updated in order to provide more accurate evidence-based treatments to patients.
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http://dx.doi.org/10.30773/pi.2020.0146DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7711116PMC
November 2020

Wilms Tumor with dilated hypertensive cardiomyopathy, acute myocarditis, pulmonary edema, and heart failure.

Urol Case Rep 2020 Nov 25;33:101391. Epub 2020 Aug 25.

Department of Urology, Pusan National University School of Medicine, Yangsan, South Korea.

An 11-month-old boy with unilateral Wilms tumor had an unusual presentation, with dilated hypertensive cardiomyopathy, acute myocarditis, pulmonary edema, and congestive heart failure secondary to the Wilms tumor and requiring intensive care. After surgery, all of the findings were normalized. According to the literature review there were reported previously in only seven cases with dilated cardiomyopathy. Wilms tumor should be included in the differential diagnosis of any child with dilated cardiomyopathy and an abdominal mass, regardless of the presence of hypertension, especially less than one year old. Also, vasoactive mediators including renin should be evaluated in the case of hypertension.
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http://dx.doi.org/10.1016/j.eucr.2020.101391DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7574032PMC
November 2020

Evaluation of Functional Bladder Capacity in Children with Nocturnal Enuresis According to Type and Treatment Outcome.

Res Rep Urol 2020 15;12:383-389. Epub 2020 Sep 15.

Department of Urology, Pusan National University School of Medicine, Yangsan, Korea.

Purpose: This study aimed to identify whether functional bladder capacity (FBC) differs among subgroups of nocturnal enuresis (NE) patients and can be used to predict treatment response.

Methods: A total of 69 children with NE were included in this study between July 2017 and February 2019 according to medical chart review, retrospectively. All patients completed a questionnaire about voiding symptoms and 48-hour frequency/volume (48-h F/V) charts. FBC was obtained from the 48-h F/V charts and uroflowmetry (UFM) with post-void residual volume (PVR). All patients were primarily treated with standard urotherapy and pharmacological therapy. The response rate was analyzed at 3 months after treatment.

Results: The mean age of the 69 patients (42 male, 27 female) was 83.3 ± 22.4 months (range, 5-13 years) at the first visit. The percentages of children with monosymptomatic NE (MNE) and non-monosymptomatic NE (NMNE) on the questionnaire were 40.6% (28/69) and 59.4% (41/69), respectively. FBC of all patients was lower than the normal range of expected bladder capacity, and there were no significant differences between measurement methods, NE types (MNE vs NMNE), or response rates (p > 0.05).

Conclusion: Children with NE had diminished FBC in both 48-h F/V charts and UFM with PVR. We found no difference in FBC by NE type or treatment outcome. Therefore, FBC cannot be used to distinguish between NE types or predict treatment responses.
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http://dx.doi.org/10.2147/RRU.S267417DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7501990PMC
September 2020

Evaluation of Functional Bladder Capacity in Children with Nocturnal Enuresis According to Type and Treatment Outcome.

Res Rep Urol 2020 15;12:383-389. Epub 2020 Sep 15.

Department of Urology, Pusan National University School of Medicine, Yangsan, Korea.

Purpose: This study aimed to identify whether functional bladder capacity (FBC) differs among subgroups of nocturnal enuresis (NE) patients and can be used to predict treatment response.

Methods: A total of 69 children with NE were included in this study between July 2017 and February 2019 according to medical chart review, retrospectively. All patients completed a questionnaire about voiding symptoms and 48-hour frequency/volume (48-h F/V) charts. FBC was obtained from the 48-h F/V charts and uroflowmetry (UFM) with post-void residual volume (PVR). All patients were primarily treated with standard urotherapy and pharmacological therapy. The response rate was analyzed at 3 months after treatment.

Results: The mean age of the 69 patients (42 male, 27 female) was 83.3 ± 22.4 months (range, 5-13 years) at the first visit. The percentages of children with monosymptomatic NE (MNE) and non-monosymptomatic NE (NMNE) on the questionnaire were 40.6% (28/69) and 59.4% (41/69), respectively. FBC of all patients was lower than the normal range of expected bladder capacity, and there were no significant differences between measurement methods, NE types (MNE vs NMNE), or response rates (p > 0.05).

Conclusion: Children with NE had diminished FBC in both 48-h F/V charts and UFM with PVR. We found no difference in FBC by NE type or treatment outcome. Therefore, FBC cannot be used to distinguish between NE types or predict treatment responses.
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http://dx.doi.org/10.2147/RRU.S267417DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7501990PMC
September 2020

Moxibustion as an adjunct for lower urinary tract symptoms associated with benign prostate enlargement: A randomized controlled pilot trial.

Medicine (Baltimore) 2020 Jan;99(4):e18918

School of Korean medicine, Pusan National University.

Background: Benign prostatic enlargement (BPE) causes discomfort in daily life, including lower urinary tract symptoms (LUTSs) caused by the enlarged prostate, and requires long-term management as a chronic, irreversible disease. To improve LUTS, certain complementary therapies have been used with or without doctors' directions. Conventional treatments and complementary therapies tend to be combined unsystematically, depending on patient preference; thus, research for safe and efficient combination therapy is warranted.

Methods: Twenty-nine participants were randomly assigned to an integrative group (IG, n = 15) or a conventional group (CG, n = 14). The IG received moxibustion (twice weekly for 4 weeks, at the acupuncture points SP6, LR3, and CV4) and conventional medication for 4 weeks, followed by conventional medication alone for 8 weeks. The CG received conventional medication alone for 12 weeks. The outcome measures were International Prostate Symptom Score (IPSS), patient's global impression of changes (PGIC), maximum urinary flow rate (Qmax), postvoid residual urine volume (PVR), and frequency-volume chart.

Results: Total IPSS (IG, -2.4 ± 4.2; CG, 0.9 ± 4.0; P = .039), PGIC-A (IG, 3.5 ± 1.0; CG, 2.2 ± 1.0; P = .001), and PGIC-B (IG, 3.5 ± 0.1; CG, 4.7 ± 0.6; P = .004) were significantly improved in the IG compared with the CG, 4 weeks after baseline. Among the IPSS items, incomplete emptying (IG, -0.6 ± 0.7; CG, 0.4 ± 1.2; P = .019), straining (IG, -0.6 ± 0.8; CG, 0.2 ± 1.2; P = .046), and nocturia (IG, -0.8 ± 1.4; CG, 0.1 ± 1.0; P = .045) showed significant differences. The Qmax and PVR volume did not differ significantly at 12 weeks after the baseline.

Conclusion: Moxibustion can be considered an adjunct therapy to improve LUTS in BPE patients. A full-sized randomized controlled trial would be feasible with comparator modifications and an extended study period. The study design should include a placebo group and narrow the eligibility to subjects who do not respond well to conventional treatments.
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http://dx.doi.org/10.1097/MD.0000000000018918DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7004691PMC
January 2020

α-Casein Changes Gene Expression Profiles and Promotes Tumorigenesis of Prostate Cancer Cells.

Nutr Cancer 2020 1;72(2):239-251. Epub 2019 Jun 1.

Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Republic of Korea.

Prostate cancer is among the most prevalent malignancies in men. High intake of dairy products is associated with an increased risk of prostate cancer. No study has examined the gene profile changes and molecular mechanism by which casein, milk protein, affects prostate cancer cells. In this study, we used gene expression profiling to identify gene changes in PC3 prostate cancer cells exposed to α-casein. α-casein altered the expression of a large number of genes-related prostate cancer, transcription factor, apoptotic, metabolic, and cell cycle pathways, in addition to the expected cell proliferation signaling pathways. To clarify the molecular events involved in the effect of α-casein on proliferation and progression of PC3 cells, we examined cell proliferation assay, quantitative real-time PCR, Western blotting, and immunohistochemical and immunofluorescence staining. α-casein promoted PC3 cell proliferation and survival under serum-free conditions by increasing the expression of E2F1 and its target gene PCNA. α-casein also protected PC3 cells from serum-starved autophagic cell death by activating the PI3K/Akt pathway through activation of mTORC1, up-regulation of p70S6K, and down-regulation of LC3 autophagosome formation. Our data provide new insights into the molecular mechanisms underlying the tumorigenic effect of α-casein in prostate cancer cells.
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http://dx.doi.org/10.1080/01635581.2019.1622742DOI Listing
December 2020

Microbiology of smegma: Prospective comparative control study.

Investig Clin Urol 2019 03 25;60(2):127-132. Epub 2019 Feb 25.

Department of Urology, Pusan National University School of Medicine, Yangsan, Korea.

Purpose: The aim of the study was to investigate the common bacteria found in the smegma in the subpreputial space of asymptomatic boys prospectively, and to determine the difference of those bacteria according to the presence of smegma.

Materials And Methods: In our institution, 40 boys who performed penoplasty were recruited into the study. Swab was done using aseptic techniques on smegma and glans in the operation room. According to the presence of smegma in the subpreputial space, we classified glans as a group S (with smegma, n=20) and group C (without smegma, n=20). The swabs were immediately sent to microbiology laboratory for microscopy, culture, and sensitivity tests.

Results: The mean age was 30.4±26.4 months. Thirty-one bacteria were isolated from smegma, comprising 15 gram-positive species (48.4%) and 16 gram-negative species (51.6%). The most commonly isolated gram-negative bacterium was (25.8%), while the commonly isolated gram-positive bacteria were (19.4%) and (12.9%). Most of the bacterial isolates were multi-drug-resistant (61.3%). In group S, 12 boys had 22 bacterial isolates in the glans. The commonly isolated bacteria were (27.3%), (22.7%) and (18.2%). In group C, 13 boys had 21 bacterial isolates in the glans. The most commonly isolated bacterium was (28.6%).

Conclusions: Smegma in the subpreputial space of children was colonized by many kinds of uropathogen.
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http://dx.doi.org/10.4111/icu.2019.60.2.127DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6397923PMC
March 2019

WITHDRAWN: HM47118A, a novel insulinotropic GPR119 agonist and potential oral antidiabetic agent.

Diabetes Res Clin Pract 2019 Jan 11. Epub 2019 Jan 11.

College of Pharmacy, Chung-Ang University, 84 Heukseok-ro, Seoul 06974, Republic of Korea. Electronic address:

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.
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http://dx.doi.org/10.1016/j.diabres.2019.01.011DOI Listing
January 2019

Pharmacological evaluation of HM41322, a novel SGLT1/2 dual inhibitor, and .

Korean J Physiol Pharmacol 2019 Jan 26;23(1):55-62. Epub 2018 Dec 26.

College of Pharmacy, Chung-Ang University, Seoul 06974, Korea.

HM41322 is a novel oral sodium-glucose cotransporter (SGLT) 1/2 dual inhibitor. In this study, the and pharmacokinetic and pharmacologic profiles of HM41322 were compared to those of dapagliflozin. HM41322 showed a 10-fold selectivity for SGLT2 over SGLT1. HM41322 showed an inhibitory effect on SGLT2 similar to dapagliflozin, but showed a more potent inhibitory effect on SGLT1 than dapagliflozin. The maximum plasma HM41322 level after single oral doses at 0.1, 1, and 3 mg/kg were 142, 439, and 1830 ng/ml, respectively, and the T was 3.1 h. HM41322 was rapidly absorbed and reached the circulation within 15 min. HM41322 maximized urinary glucose excretion by inhibiting both SGLT1 and SGLT2 in the kidney. HM41322 3 mg/kg caused the maximum urinary glucose excretion in normoglycemic mice (19.32±1.16 mg/g) at 24 h. In normal and diabetic mice, HM41322 significantly reduced glucose excursion. Four-week administration of HM41322 in mice reduced HbA1c in a dose dependent manner. Taken together, HM41322 showed a favorable preclinical profile of postprandial glucose control through dual inhibitory activities against SGLT1 and SGLT2.
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http://dx.doi.org/10.4196/kjpp.2019.23.1.55DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6315097PMC
January 2019

Impact of sporicidal fumigation with methyl bromide or methyl iodide on electronic equipment.

J Environ Manage 2019 Feb 13;231:1021-1027. Epub 2018 Nov 13.

United States Environmental Protection Agency, 109 TW Alexander Dr, Research Triangle Park, NC, 27709, USA. Electronic address:

The effect of sporicidal fumigation with methyl bromide or methyl iodide on the functionality of valuable electronic equipment was evaluated using desktop computers as surrogates under target conditions of 200-250 mg/L fumigant for 48 h at 24-30 °C and 75-85% RH. Methyl iodide fumigation damaged light-emitting diodes and optical films in computer displays that were powered-on during fumigation. After five months of post-fumigation operation, five out of six methyl-bromide-fumigated and all six methyl-iodide-fumigated DVD ± RW optical drives failed. Deterioration of rubber spacers critical to maintaining correct disc geometry caused the failure. Metal coupons, included to measure corrosion, showed no significant differences in weight gain between control and fumigation conditions. Relative humidity sensors exhibited a substantial and sometimes irreversible reduction in sensitivity during and after methyl iodide fumigation. Methyl bromide and methyl iodide can cause damage to electronic equipment, but damage seems to be limited to organic materials rather than corrosion of metal surfaces.
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http://dx.doi.org/10.1016/j.jenvman.2018.10.118DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6319391PMC
February 2019

Alternative fast analysis method for cellulose sponge surface sampling wipes with low concentrations of Bacillus Spores.

J Microbiol Methods 2019 01 16;156:5-8. Epub 2018 Nov 16.

Jacobs Technology, Inc., 600 William Northern Blvd, Tullahoma, TN 37388, USA.

Environmental sampling is a critical component of the post decontamination verification process following a bioterrorism event. The current work was performed to produce a less labor-intensive method for processing cellulose sponge-wipes used for sampling areas potentially contaminated with low concentrations (i.e., post-decontamination) of Bacillus anthracis spores. An alternative fast-analysis processing method was compared to the processing protocol validated by the Centers for Disease Control and Prevention (CDC) for the Laboratory Response Network (LRN). Glazed tile coupons (1102 cm) were inoculated with 50, 500, or 5000 spores of Bacillus thuringiensis subsp. kurstaki (Btk), then sampled with cellulose sponges. Sampling was limited to a 25- by 25-cm area and performed in the same manner as the CDC sampling method. Samples were then processed using either the alternative "Fast Analysis" method or the "CDC method". Three different analysts repeated the tests at each concentration utilizing each method. Mean recoveries, labor time, and potentially hazardous waste produced were compared for the two methods. The mean percent recoveries and standard errors for the samples processed using the "CDC method" were 39.9 ± 6.7, 43 ± 7.6, and 36.8 ± 10.1 for the 5000, 500, and 50 spore loading levels, respectively; compared to 54.2 ± 12.9, 64.2 ± 21.7, and 45.2 ± 8.6 for the "Fast Analysis" method. At each titer tested the "Fast Analysis" method resulted in a statistically significant higher percent recovery. Furthermore, analysts processed samples utilizing the "Fast Analysis" method in less than half the time and generated half as much potentially hazardous waste compared to the "CDC method".
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http://dx.doi.org/10.1016/j.mimet.2018.11.013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6359940PMC
January 2019

Quantitative screening for endocrine-disrupting bisphenol A in consumer and household products using NanoAptamer assay.

Chemosphere 2018 Nov 24;211:72-80. Epub 2018 Jul 24.

Department of Environmental Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea. Electronic address:

The NanoAptamer assay is a bisphenol A (BPA) quantification method that uses magnetic beads, quantum dot nanoparticles, and a BPA-specific aptamer. In this study, screening of various consumer and household products for BPA was demonstrated utilizing the NanoAptamer assay. First, the experimental conditions suitable for BPA detection using the NanoAptamer assay were examined in terms of incubation time, temperature, and buffer composition. The range of BPA quantification via the NanoAptamer assay was determined to be 0.005-1000 ng/mL of BPA. The selectivity was confirmed by detecting BPA in an analog mixture containing bisphenol S and bisphenol F. Finally, a leaching experiment using 20 consumer and household products classified into 4 categories was performed to demonstrate the capability of the NanoAptamer assay for BPA detection. The experiment was validated by high-performance liquid chromatography analysis (correlation coefficient, r = 0.99).
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http://dx.doi.org/10.1016/j.chemosphere.2018.07.125DOI Listing
November 2018

Cesium emissions from laboratory fires.

J Air Waste Manag Assoc 2018 11 7;68(11):1211-1223. Epub 2018 Sep 7.

c Decontamination and Consequence Management Division , National Homeland Security Research Center, U.S. Environmental Protection Agency, Research Triangle Park , NC , USA.

If a radiological incident such as a nuclear power plant accident, a radiological dispersal device, or detonation of an improvised nuclear device occurs, significant areas may be contaminated. Initial cleanup priorities would likely focus on populated areas, leaving the forested areas to pass several seasons where the overhead canopy materials would fall to the forest floor. In the event of a wildfire in a radionuclide-contaminated forest, some radionuclides would be emitted in the air while the rest would remain in the ash. This paper reports on a laboratory simulation study that examines the partitioning of cesium-133 (a nonradioactive isotope of cesium) between airborne particulate matter and residual nonentrained ash when pine needles and peat are doped with cesium. Only 1-2.5% of the doped cesium in pine needles was emitted as particulate matter, and most of the cesium was concentrated in the particulate fraction greater than 10 µm in aerodynamic diameter. For peat fires, virtually all of the cesium remained in the ash. The results from this study will be used for modeling efforts to assess potential exposure risks to firefighters and the surrounding public. Implications: There is a potential for emissions of radionuclides such as cesium-137 from a wildfire over a radionuclide-contaminated forest. This paper reports on a laboratory simulation study of a wildfire with two types of biomass doped with nonradioactive cesium. This simulation suggests that only 1-2.5% of the cesium in the biomass will be emitted from the wildfire, while the rest will reside in the residual ash. In this study, pine needles were the only contributor to the air emissions of cesium; duff was not a source of cesium emissions. In this study, cesium emitted from the simulated wildfire was concentrated in the particle sizes larger than 10 µm.
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http://dx.doi.org/10.1080/10962247.2018.1493001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6200644PMC
November 2018

The Expression of Androgen Receptor and Its Variants in Human Prostate Cancer Tissue according to Disease Status, and Its Prognostic Significance.

World J Mens Health 2019 Jan 16;37(1):68-77. Epub 2018 Apr 16.

Department of Anatomy, Pusan National University School of Medicine, Yangsan, Korea.

Purpose: To evaluate changes in the expression of androgen receptor (AR) and its variants (ARVs) in human prostate cancer (PCa) tissues according to disease status, and its prognostic significance following radical prostatectomy (RP).

Materials And Methods: A total of 282 PCa cases were evaluated, which included 252 localized PCa, 8 metastatic castration resistant prostate cancer (CRPC), and 22 benign prostatic hyperplasia (BPH) cases. Samples were collected from patients who underwent RP or transurethral resection and were stored in ethically approved tissue banks. Quantitative real-time polymerase chain reaction, Western blotting, and immunohistochemistry were performed for AR and ARVs. Each tissue was confirmed as cancerous (greater than 80%) using hematoxylin and eosin staining. AR and ARVs expression was compared according to disease status. The biochemical recurrence free survival (BCRFS) rates in men with localized PCa was analyzed according to AR and ARV7 expression using the Kaplan-Meier curve.

Results: Only 58 of the 252 localized PCa were included in the analysis because of insufficient cancer tissue. AR and ARV7 mRNA expression was higher in the CRPC tissue than in the localized PCa tissue (p=0.025, p=0.002, respectively). In localized PCa tissue, high AR mRNA and protein level was associated with a low BCRFS rate (log-ranked, p=0.019, p<0.001, respectively).

Conclusions: Overall AR and ARV7 mRNA expression levels were increased in CRPC tissues compared to localized PCa and BPH tissues. High AR protein and mRNA expression in the tumor tissue may be considered a predictive factor of BCRFS following RP.
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http://dx.doi.org/10.5534/wjmh.180003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6305860PMC
January 2019

Can recording only the day-time voided volumes predict bladder capacity?

Investig Clin Urol 2018 05 19;59(3):194-199. Epub 2018 Mar 19.

Department of Urology, Soonchunhyang University Bucheon Hospital, Bucheon, Korea.

Purpose: This study aimed to demonstrate a method to easily assess bladder capacity using knowledge of day-time voided volumes, which can be obtained even from patients with nocturnal enuresis where the first morning void cannot accurately predict the bladder capacity due to bladder emptying overnight.

Materials And Methods: We evaluated 177 healthy children from 7 Korean medical centres entered the study between January 2008 and January 2009. Voided volumes measured for more than 48 hours were recorded in the frequency volume chart (FVC).

Results: Most voided volumes during day-time were showed between 30% and 80% of the maximal voided volume (MVV). The maximal voided volume during day-time (MVVDT) was significantly less than the MVV (179.5±71.1 mL vs. 227.0±79.2 mL, p<0.001). The correlation coefficients with the MVV were 0.801 for the estimated MVV using the MVVDT (MVVDT×1.25), which suggested a fairly strong relationship between the MVVDT×1.25 and the MVV.

Conclusions: The MVV derived from the FVC excluding the FMV was less than if the FMV had been included. When an accurate first morning voided volume cannot be obtained, as in patients with nocturnal enuresis, calculating MVVDT×1.25 allows estimation of the bladder capacity in place of the MVV.
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http://dx.doi.org/10.4111/icu.2018.59.3.194DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5934282PMC
May 2018

Current Issues in Adolescent Varicocele: Pediatric Urological Perspectives.

World J Mens Health 2018 May 22;36(2):123-131. Epub 2018 Mar 22.

Department of Urology, Pusan National University School of Medicine, Yangsan, Korea.

While varicocele is the most common cause of surgically correctable infertility in adult males, with repair resulting in improved semen parameters in 60% to 80% of men and a higher likelihood of conception in up to 60% of men, the rationale for varicocele repair in the pediatric population is less clear. Additionally, prepubertal varicoceles are much less common and their management is controversial. Adolescents with a varicocele are often in the midst of a progressive disease process. Despite the high prevalence of varicocele and its association with progressive disease processes, the indications for adolescent varicocele repair and the effects thereof on paternity have been persistently challenging to study. This review will briefly present some of the current issues regarding adolescent varicocele from a pediatric urological point of view, including the evaluation of adolescent varicocele, the optimal surgical indications, the optimal choice of surgical intervention to be performed, and outcomes.
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http://dx.doi.org/10.5534/wjmh.170053DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5924953PMC
May 2018

The safety of a mixture of bupivacaine and lidocaine in children after urologic inguinal and scrotal surgery.

Investig Clin Urol 2018 03 1;59(2):141-147. Epub 2018 Feb 1.

Department of Urology, Pusan National University School of Medicine, Yangsan, Korea.

Purpose: Local anesthetic agents such as bupivacaine and lidocaine are commonly used after surgery for pain control. The aim of this prospective study was to evaluate the safety of a mixture of bupivacaine and lidocaine in children who underwent urologic inguinal and scrotal surgery.

Materials And Methods: Fifty-five patients who underwent pediatric urologic outpatient surgeries, were prospectively enrolled in this study. The patients were divided into three groups according to age (group I: under 2 years, group II: between 3-4 years, and group III: 5 years and above). Patients were further sub-divided into unilateral and bilateral groups. All patients were injected with a mixture of 0.5% bupivacaine and 2% lidocaine (2:1 volume ratio) at the surgical site, just before the surgery ended. Hemodynamic and electrocardiographic parameters were measured before local anesthesia, 30 minutes after administration of local anesthesia, and 60 minutes after administration.

Results: The patients' mean age was 40.5±39.9 months. All patients had normal hemodynamic and electrocardiographic parameters before local anesthesia, after 30 minutes, and after 60 minutes. Also, results of all intervals were within normal values, when analyzed by age and laterality. No mixture related adverse events (nausea, vomiting, pruritus, sedation, respiratory depression) or those related to electrocardiographic parameters (arrhythmias and asystole) were reported in any patients.

Conclusions: A mixture of bupivacaine and lidocaine can be safely used in children undergoing urologic inguinal and scrotal surgery. An appropriate dose has no clinically significant hemodynamic or cardiac changes and adverse effects.
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http://dx.doi.org/10.4111/icu.2018.59.2.141DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5840119PMC
March 2018

Microquantitation of Prostate-Speciflc Antigen by Using Antibody-Conjugated Magnetic Microsphere Beads.

J Nanosci Nanotechnol 2018 Feb;18(2):1474-1477

College of Pharmacy, Sunchon National University, Sunchon, Jeonnam 57922, Korea.

Prostate-specific antigen (PSA) is a glycoprotein that is secreted by prostate gland epithelial cells, and elevation of PSA level in serum is often observed with prostate cancer or prostate disorders. Therefore, detection of PSA level in patient specimens is used as a diagnostic marker when screening of prostate cancer. In this study, we developed PSA antibody-conjugated microsphere beads that can be used for quantitation of PSA. We optimized the procedure for bead preparation and validated the detection analysis by using LNCaP and DU-145 prostate cancer cell lysates. By applying the procedure, extracellular PSA from culture media of LNCaP cells and standard PSA proteins were quantified to assess whether the antibody-conjugated microsphere bead can be used to detect trace amounts of PSA. The PSA level results obtained by using the antibody-conjugated microsphere beads indicate that the procedure is sensitive and quantitative in analyzing PSA. Taken together, the results suggest that the method is suitable for microquantitation of PSA from patient specimens.
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http://dx.doi.org/10.1166/jnn.2018.14861DOI Listing
February 2018

Comparison of penile length at 6-24 months between children with unilateral cryptorchidism and a healthy normal cohort.

Investig Clin Urol 2018 01 15;59(1):55-60. Epub 2017 Dec 15.

Department of Urology, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Korea.

Purpose: Urologic diseases affected by testosterone can be associated with smaller penis size compared to the normal population. We sought to compare penile length in children with unilateral cryptorchidism and normative data from a cohort of healthy Korean boys.

Materials And Methods: This study was performed in 259 Korean boys (212, normal cohort; 47, cryptorchidism) aged 6-24 months, each of whom had been brought to an outpatient clinic at one of five tertiary hospitals (Gyeongsangnam-do Province) between April 2014 and June 2015. Penile length was measured via stretched penile length (SPL) and testicular size was measured using orchidometry (mL).

Results: SPL in children with cryptorchidism was significantly shorter compared to a cohort of healthy Korean boys aged 6-24 months (3.7±0.5 cm and 4.3±0.8 cm, p<0.001), although there were no differences with regard to height, body weight and contralateral testicular size between the two groups. According to the stratified ages (6-12, 12-18, and 18-24 months), SPL in children with cryptorchidism was persistently shorter at their ages than those without.

Conclusions: It might be that the penile length aged 6-24 months of children with unilateral cryptorchidism is shorter than that of a cohort of healthy Korean boys.
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http://dx.doi.org/10.4111/icu.2018.59.1.55DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5754584PMC
January 2018

Impact of repeated extracorporeal shock wave lithotripsy on prepubertal rat kidney.

Urolithiasis 2018 Nov 8;46(6):549-558. Epub 2017 Nov 8.

Department of Urology, Pusan National University School of Medicine, Yangsan, Korea.

This study aimed to investigate the effects of repeated extracorporeal shock wave lithotripsy (ESWL) on the kidneys of prepubertal and adult rats. Thirty rats were used: 15 were prepubertal (3 weeks of age) with an average body weight of 72.3 ± 3.3 g, and 15 were adults with of 265 ± 11.3 g. The prepubertal and adult rats were separately and randomly allocated to three groups, each consisting of five rats. Following anesthetization, the left kidney of each rat in each group received shock waves in one, two, or three sessions separated by 72 h. The rats in each group were killed 72 h after the last ESWL session, and both kidneys were harvested; the right kidney was used as the control. Renal injury was examined with histological analysis, immunohistochemistry, and Western blot to detecting the expression of heat-shock protein-70, tumor necrosis factor-alpha-α, intercellular adhesion molecule-1, and monocyte chemoattractant protein-1 as markers of renal damage. All of these markers were similarly increased with increased ESWL sessions in both age groups. Histological analysis revealed more serious fibrosis and inflammation in the ESWL-treated kidneys in both groups than in the controls, with the damage increasing with increasing numbers of sessions. ESWL on the kidney increased renal damage according to the number of sessions in both age groups of rats, and the effects of ESWL on renal injury were similar in the two groups. However, there were generally no significant differences in the effects of ESWL on molecular indicators of renal injury between prepubertal and adult rats.
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http://dx.doi.org/10.1007/s00240-017-1011-0DOI Listing
November 2018

Pedobacter kyonggii sp. nov., a psychrotolerant bacterium isolated from forest soil.

Int J Syst Evol Microbiol 2017 Dec 19;67(12):5120-5127. Epub 2017 Oct 19.

Department of Life Science, College of Natural Sciences and Engineering, Kyonggi University, Suwon, Gyeonggi-Do 16227, Republic of Korea.

Strain K-4-11-1, a psychrotolerant, light salmon-coloured, Gram-stain-negative, non-motile and rod-shaped bacterium, was isolated from forest soil of Kyonggi University, Suwon, South Korea. It was able to grow at 0-32 °C, at pH 5.0-10.0 and with 0-1.5 % (w/v) NaCl. This strain was taxonomically characterized by a polyphasic approach. Based on 16S rRNA gene sequence analysis, strain K-4-11-1 belongs to the genus Pedobacter and is closely related to Pedobacter ginsenosidimutans THG-45 (98.75 % sequence similarity), Pedobacter borealis G-1 (98.48 %), Pedobacter terrae DS-57 (98.20 %), Pedobacter agri PB92 (97.92 %) and Pedobacter suwonensis 15-52 (97.84 %). The only respiratory quinone was menaquinone-7. The major polar lipids were phosphatidylethanolamine and unidentified glycolipids. The predominant fatty acids of strain K-4-11-1 were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), iso-C15 : 0, iso-C17 : 0 3-OH, anteiso-C17 : 0 and summed feature 9 (iso-C17 : 1ω9c and/or C16 : 0 10-methyl). The genomic DNA G+C content of this novel strain was 38.3 mol%. The DNA-DNA relatedness values between strain K-4-11-1 and P. ginsenosidimutans KACC 14530, P. borealis KACC 14287, P. terrae KACC 13766, P. agri KACC 13768 and P. suwonensis KACC 11317 were 40.0, 36.3, 37.0, 32.3 and 29.7 %, respectively. The morphological, physiological, chemotaxonomic and phylogenetic analyses clearly distinguished this novel strain from its closest phylogenetic neighbours. Thus, strain K-4-11-1 represents a novel species of the genus Pedobacter, for which the name Pedobacter kyonggii sp. nov. is proposed. The type strain is K-4-11-1 (=KEMB 9005-574=KACC 19174=JCM 31916).
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http://dx.doi.org/10.1099/ijsem.0.002428DOI Listing
December 2017

Porphyrobacter algicida sp. nov., an algalytic bacterium isolated from seawater.

Int J Syst Evol Microbiol 2017 Nov 6;67(11):4526-4533. Epub 2017 Oct 6.

Department of Life Science, College of Natural Sciences, Kyonggi University, Suwon 16227, Republic of Korea.

A novel Gram-stain-negative, yellow-pigmented, catalase- and oxidase-positive, non-endospore-forming, flagellated bacterium, designated strain Yeonmyeong 2-22, was isolated from surface seawater of Geoje Island, Republic of Korea. Strain Yeonmyeong 2-22 showed algalytic activity against the seven strains tested: Cochlodinium polykrikoides, Chattonella marina, Heterosigma akashiwo, Scrippsiella trochoidea, Heterocapsa triquetra, Prorocentrum minimum and Skeletonema costatum. A taxonomic study was carried out based on a polyphasic approach to characterize the exact taxonomic position of strain Yeonmyeong 2-22. The bacterium was able to grow at 10-40 °C, at salinities from 0 to 9 %, at pH from 4.0 to 9.0 and was not able to degrade gelatin or casein. Phylogenetic analysis of 16S rRNA gene sequences revealed that strain Yeonmyeong 2-22 was considered to represent a novel species of the genus Porphyrobacter, which belongs to the family Erythrobacteraceae, and was related most closely to Porphyrobacter dokdonensis DSW-74 with 97.23 % 16S rRNA gene sequence similarity. The dominant cellular fatty acids of strain Yeonmyeong 2-22 were C18 : 1ω7c (49.7 %), C16 : 0 (12.0 %) and 11-methyl C18 : 1ω7c (11.5 %), and ubiquinone-10 (Q-10) was the predominant respiratory lipoquinone. The genomic DNA G+C content of strain Yeonmyeong 2-22 was calculated to be 63.0 mol%. Phenotypic characteristics of the novel strain also differed from other members of the genus Porphyrobacter. On the basis of polyphasic taxonomic data, strain Yeonmyeong 2-22represents as a novel species of the genus Porphyrobacter, for which the name of Porphyrobacter algicida sp. nov. is proposed. The type strain is Yeonmyeong 2-22 (=KEMB 9005-328=JCM 31499).
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http://dx.doi.org/10.1099/ijsem.0.002324DOI Listing
November 2017

Lysobacter olei sp. nov., isolated from oil-contaminated soil.

Int J Syst Evol Microbiol 2017 Nov 6;67(11):4660-4666. Epub 2017 Oct 6.

Department of Life Science, College of Natural Sciences and Engineering, Kyonggi University, Suwon, Gyeonggi-Do 16227, Republic of Korea.

Strain D-14, a brown-coloured, Gram-stain-negative, non-motile and rod-shaped bacterium, was isolated from oil-contaminated soil. It was able to grow at 20-40 °C, at pH 6.0-10.0 and at 0-1 % (w/v) NaCl concentration. Based on the 16S rRNA gene sequence analysis, strain D-14 belonged to the genus Lysobacter and was closely related to Lysobacter caeni BUT-8 (99.0 % sequence similarity), Lysobacter ruishenii CTN-1 (98.5 %), Lysobacter daejeonensis GH1-9 (98.2 %) and Lysobacter panacisoli CJ29 (97.2 %). The only respiratory quinone was ubiquinone-8. The polar lipid profile revealed the presence of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and phosphatidyl-N-methyl-ethanolamine. The predominant fatty acids of strain D-14 were iso-C15 : 0, iso-C16 : 0, summed feature 9 (iso-C17 : 1 ω9c and/or C16 : 0 10-methyl), summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), iso-C14 : 0, C11 : 0iso 3-OH, C15 : 1iso F and C16 : 0. The genomic DNA G+C content of this novel strain was 68.7 mol%. The DNA-DNA relatedness values between strain D-14 and L. caeni BUT-8, L. ruishenii CTN-1, L. daejeonensis GH1-9 and L. panacisoli CJ29 were 56.0, 46.3, 48.7 and 41.7 %, respectively, which fall below the threshold value of 70 % for the strain to be considered as novel. The morphological, physiological, chemotaxonomic and phylogenetic analyses clearly distinguished this strain from its closest phylogenetic neighbours. Thus, strain D-14 represents a novel species of the genus Lysobacter, for which the name Lysobacterolei sp. nov. is proposed. The type strain is D-14 (=KEMB 9005-572=KACC 19173=JCM 31917).
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http://dx.doi.org/10.1099/ijsem.0.002348DOI Listing
November 2017

A preliminary analysis of the diet composition of overwintering Bean geese () and greater white-fronted geese () in Korea using PCR on fecal samples.

Anim Cells Syst (Seoul) 2017 13;21(2):141-145. Epub 2017 Apr 13.

Department of Environmental Science and Engineering, College of Engineering, Ewha Womans University, Seoul, Korea.

Bean geese () and Greater white-fronted geese () are the dominant wintering waterfowl in South Korea. Although they are commonly observed in estuaries and rice fields during the winter, the diet composition of the geese during the winter has rarely been studied. In this study, we provide the results from preliminary analyses on the diet of these two geese species overwintering in Daebu Island of South Korea. We used a total of 13 fecal samples from Bean geese ( = 4) and Greater white-fronted geese ( = 9), and performed a BLAST search for the sequences obtained from 87 clones ( = 36 for Bean geese and  = 51 for Greater white-fronted geese). The diet of Bean geese consisted of five families of plants: Caryophyllaceae (75.0%), Poaceae (13.9%), Asteraceae (5.5%), Polygonaceae (2.8%) and Cucurbitacea (2.8%). On the other hand, the diet of Greater white-fronted geese consisted of 6 families of plants: Poaceae (74.5%), Caryophyllaceae (9.8%), Solanacea (5.9%), Portulacaceae (3.9%), Lamiaceae (3.9%) and Brassicaceae (2.0%). We found that plants of the rice family (Poaceae) are important in the diet of wintering geese, especially for Greater white-fronted geese. This knowledge can be used to establish conservation strategies of the geese overwintering in South Korea.
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http://dx.doi.org/10.1080/19768354.2017.1308437DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6138343PMC
April 2017

Highly Sensitive Detection of Bisphenol A by NanoAptamer Assay with Truncated Aptamer.

ACS Appl Mater Interfaces 2017 May 20;9(17):14889-14898. Epub 2017 Apr 20.

Department of Environmental Science and Engineering, Ewha Womans University , Seoul 03760, Republic of Korea.

For the sensitive quantification of bisphenol A (BPA), we have developed NanoAptamer assay, which employs aptamer and complementary signaling DNA, a set of quantum dots (QD), and magnetic beads (MBs). Signaling DNA-QD was tethered to MB-QD via the aptamer. The affinity of the aptamer to BPA resulted in the release of the signaling DNA-QD from the complex and hence the corresponding decrease in the QD fluorescence measurement signal. Three new aptamers (23, 58, and 24-mer) were designed via truncation of the reference aptamer (73-mer). The sensitivity and selectivity of each aptamer for BPA detection via NanoAptamer assay were investigated. One of the truncated aptamers (24-mer) has shown a significantly better performance (limit of detection, LOD, 0.17 pg/mL) than the reference 73-mer aptamer (LOD, 570 pg/mL). It has also shown the best selectivity for BPA detection over BPA analogues (i.e., bisphenol B, bisphenol C, and diethylstilbestrol). It corresponded to a normalized fluorescence change of 33.7% at the environmentally relevant concentration of 1 ng/mL (1 ppb) BPA; however, the analogues remained unchanged (2.3-3.9%).
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http://dx.doi.org/10.1021/acsami.7b02377DOI Listing
May 2017

Composite Electrolyte for All-Solid-State Lithium Batteries: Low-Temperature Fabrication and Conductivity Enhancement.

ChemSusChem 2017 05 5;10(10):2175-2181. Epub 2017 Apr 5.

New and Renewable Energy Research Division, Korea Institute of Energy Research, 152 Gajeong-ro, Yuseong-gu, Daejeon, 34129, Republic of Korea.

All-solid-state lithium batteries offer notable advantages over conventional Li-ion batteries with liquid electrolytes in terms of energy density, stability, and safety. To realize this technology, it is critical to develop highly reliable solid-state inorganic electrolytes with high ionic conductivities and adequate processability. Li Al Ti (PO ) (LATP) with a NASICON (Na superionic conductor)-like structure is regarded as a potential solid electrolyte, owing to its high "bulk" conductivity (ca. 10  S cm ) and excellent stability against air and moisture. However, the solid LATP electrolyte still suffers from a low "total" conductivity, mainly owing to the blocking effect of grain boundaries to Li conduction. In this study, an LATP-Bi O composite solid electrolyte shows very high total conductivity (9.4×10  S cm ) at room temperature. Bi O acts as a microstructural modifier to effectively reduce the fabrication temperature of the electrolyte and to enhance its ionic conductivity. Bi O promotes the densification of the LATP electrolyte, thereby improving its structural integrity, and at the same time, it facilitates Li conduction, leading to reduced grain-boundary resistance. The feasibility of the LATP-Bi O composite electrolyte in all-solid-state Li batteries is also examined in this study.
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http://dx.doi.org/10.1002/cssc.201700104DOI Listing
May 2017