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OBJECTIVES To compare the effects of taking tadalafil 5 mg and placebo once daily on post-micturition dribble (PMD) in men with lower urinary tract symptoms (LUTS). PATIENTS AND METHODS Our prospective, randomized, double-blind, placebo-controlled, multicentre trial enrolled 102 men with PMD and other LUTS. PMD was assessed using the Hallym Post-Micturition Dribble Questionnaire (HPMDQ) and according to PMD volume. Over a 12-week period, patients took either tadalafil 5 mg (n = 51) or placebo (n = 51) once daily and their HPMDQ and PMD volume results were evaluated. Adverse events (AEs) were also reported. RESULTS Over the course of 12 weeks, total HPMDQscores and PMD volumes improved significantly more in the tadalafil group than in the placebo group (reduction of total HPMDQ score of ≥2 points in the tadalafil and placebo group in 68.8% and 31.9% of patients (P 0.05), and no serious AEs were observed. CONCLUSION Taking tadalafil 5 mg once daily reduced PMD symptom severity and PMD volume in men with PMD, without inducing serious AEs, more effectively than placebo, suggesting that taking tadalafil 5 mg once daily may be an effective and well-tolerated PMD treatment.

Poly(lactic acid)(PLA)/lipophilized graphene oxide (LGO) nanohybrids were prepared using a solution blending method. Graphene oxide (GO) was synthesized using a modified Hummers method and then lipophilized by functionalization with alkylamines such as octylamine (OA), dodecylamine (DA), or octadecylamine (ODA). The PLA/GO (PG) nanohybrids were also prepared for comparison. Among the LGOs, ODA-GO was chosen to produce the PLA/LGO (PLG) nanohybrids because ODA-GO exhibited obvious intercalation behavior and the best dispersibility in chloroform. The properties of the PGs and PLGs were examined by scanning electron microscopy, wide-angle X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, universal testing machine, chemical resistance test, and hydrolytic degradable analysis. The hydrophobic ODA-GO (LGO) was dispersed on the nanoscale within the PLA matrix and the resulting nanohybrids showed significantly higher chemical resistance and reduced hydrolytic degradation.

Objectives/Hypothesis Unilateral cochlear implantation has emerged as a widely accepted procedure to treat severe to profound hearing loss, but many studies have reported benefits in terms of speech comprehension when listeners with residual low-frequency hearing in the nonimplanted ear use a hearing aid. Study Design Retrospective study. Methods In this study, we analyzed the speech performance and satisfaction of bimodal hearing according to the residual low-frequency hearing level in the nonimplanted ear. Based on low-frequency pure-tone audiometry (average of 250 Hz and 500 Hz) in the nonimplanted ear, we classified individuals into three groups as follows: group A (under 70 dB), group B (71–90 dB), and group C (over 91 dB). Listeners were tested using the Word Recognition Score, the Korea-Central Institute for Deaf sentence recognition test, and the Korean version of the Hearing Handicap Inventory for the Elderly questionnaire. Results We observed a bimodal benefit when the residual low-frequency threshold was less than 70 dB HL and a greater satisfaction with bimodal hearing compared to cochlear implant alone, when the residual low-frequency threshold was less than 70 dB HL. Conclusions This study supports the benefits of bimodal hearing in listeners with bilateral severe to profound sensorineural hearing loss as standard clinical practice, when the residual low-frequency hearing threshold is under 70 dB in the nonimplanted ear. Level of Evidence 4 Laryngoscope, 126:2817–2822, 2016

The aim of this study is to evaluate whether polylactic acid (PLA) microspheres and adipose-derived stromal vascular fraction (SVF) cells have appropriate properties as an injectable bulking agent in urologic field. Forty male Sprague-Dawley rats (2-week-old) were randomized into two groups. A total of 0.05 mL of PLA microsphere suspension and 0.05 mL of PLA microsphere suspension mixed with PKH26-labeled SVF cells were injected into bladder wall in group I and group II, respectively. At 2, 8, 16, and 24 weeks of PLA microspheres injection, the volumes of implants were measured and bladder tissues including implants were analyzed and compared grossly and histologically between groups. The distant organs were examined histologically to determine migration of PLA microspheres. At 24 weeks of implantation, 65-70% of injected volume was maintained and there was no significant difference between groups. In histological analyses, injected PLA microspheres were localized in muscular layer of bladder without infiltration into adjacent layer. From 8 to 16 weeks of injection, hybrid tissues contained collagen and actin were observed between PLA microspheres and these findings were more clear in group II. PHK26-labeled SVF cells were identified by fluorescence microscopy at all time points. There was no migration of PLA microspheres to other organs and no abnormality in weight gain and hematologic values. These results suggest the possibility of PLA microspheres as a potentially useful bulking agent in urologic field. And further investigation is needed to know synergic effect of SVF cells.

Waterborne polyurethane (WBPU) dispersions were prepared by pre-polymer process using siloxane polyol, namely polydimethylsiloxane (PDMS), and polyester polyol, namely poly(tetramethyleneadipate glycol) (PTAd), as a soft segment. Three different molecular weights (Mn = 550, 6000, 110,000) of PDMS and one fixed molecular weight of PTAd (Mn = 2000) was used during preparation of WBPU dispersions. This research aims to explore the potential use of PDMS in complementing WBPU by boosting flexibility, water resistance, and adhesive strength. The water swelling (%), tensile strength, and adhesive strength of WBPUs were investigated with respect to PDMS molecular weight and PDMS content (PDMS mol %). The water swelling (%) and tensile strength decreased with increasing PDMS molecular weight at a fixed PDMS content (mol %) in mixed polyol of WBPU films. By contrast, the peel adhesive strength peaked at 6.64 mol % and 4.43 mol % with molecular weight of PDMS at 550 and 6000, respectively, while it only decreased when the molecular weight of PDMS stood at 110,000. The adhesive strength was almost unaffected with optimum content (6.64 mol %) of lower PDMS molecular weight (Mn = 550) in mixed polyol-based WBPU after immersing the adhesive bonded nylon fabrics in water for 48 h among all of the samples. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Regioregular poly(3-hexylthiophene)-b-poly(1H,1H-dihydro perfluorooctyl methacrylate) (P3HT-b-PFOMA) diblock copolymers were synthesized by atom transfer radical polymerization of fluorooctyl methacrylate using bromoester terminated poly(3-hexylthiophene) macroinitiators in order to investigate their morphological properties. The P3HT macroinitiator was previously prepared by chemical modification of hydroxy terminated P3HT. The block copolymers were well characterized by 1H NMR spectroscopy and gel permeation chromatography. Transmission electron microscopy was used to investigate the nanostructured morphology of the diblock copolymers. The block copolymers are able to undergo microphase separation and self-assemble into well-defined and organized nanofibrillar-like micellar morphology. The development of the morphology of P3HT-b-PFOMA block copolymers was investigated after annealing in solvent vapor and also in supercritical CO2. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

Objectives: To determine the association of vesico-urethral anastomosis location (VUAL) with early recovery of urinary continence (UC) after radical prostatectomy (RP). Methods: A retrospective analysis of 678 patients who underwent RP was carried out. Patients were divided into three groups based on the VUAL as determined by postoperative cystography: group I – VUAL above the upper margin of the symphysis pubis (SP), group II – between the upper margin and the middle of the SP, and group III – below the middle of the SP. Early recovery of UC was defined as using no pads or an occasional security pad within 3 months. Recovery rates were compared between the groups and factors predicting an early recovery of UC were investigated. Results: Among all patients, 62.2% achieved an early recovery of UC. Patients in group I were younger, with a longer membranous urethra, greater percent of nerve sparing and shorter time to continence than those in groups II or III. Early recovery rates were 89.5%, 69.8% and 40.7% in group I, II and III, respectively (P < 0.001). VUAL remained an independent predictor of early recovery of UC (OR 3.2 for group I vs II and 10.8 for group I vs III [P < 0.001]) when adjusted for age, operative time, membranous urethral length and operation by surgeon with high surgical volume. Conclusion: VUAL represents an independent predictor of recovery of UC after RP. A higher VUAL is associated with a higher rate of early recovery of UC.

Objectives: To analyze the characteristics and the prognostic significance of chromophobe renal cell carcinomas (chRCC). Methods: Data about 2981 patients with non-metastatic renal cell carcinomas (RCC) at the time of surgery were retrospectively collected from 26 institutions between 1998 and 2008. All patients had undergone partial or radical nephrectomies. Of the 2981 patients, 2602 patients with conventional RCC (cRCC) and 148 with chRCC were studied. Clinical and pathological parameters were determined in all patients. Recurrence-free survival (RFS) and cancer-specific survival (CSS) were assessed. Results: Patients with chRCC differed significantly from those with cRCC on the following parameters: younger age (P = 0.026), greater female ratio (P

Three series of isocyanate-reactive waterborne polyurethane adhesives were prepared with various contents of chain extender (4.25/8.25/12.50 mol %) and polyol (20.75/16.75/12.50 mol %). Each series had a fixed amount of excess (residual) NCO group (0.50–2.00 mol %). FTIR and 1H-NMR spectroscopy identified the formation of urea crosslink structure mainly above 80°C of various cure temperatures (20–120°C) with excess diisocyanate. The molecular weight, tensile strength, Young's modulus, and adhesive strength depend on excess NCO content and cure temperature and also varied with polyol and chain extender content. The optimum cure temperature was 100°C for all the samples. The tensile strength, Young's modulus, and adhesive strength increased with increasing cure temperature above 60°C up to the optimum temperature) (100°C) and then almost leveled off. Among all the samples, the maximum values of tensile strength, Young's modulus, and adhesive strength were found with 63.22 wt % polyol, 0.93 wt % chain extender, and 1.50 mol % excess (residual) NCO content at 100°C optimum cure temperature. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Study Type – Prognosis (case series) Level of Evidence 4 OBJECTIVE To investigate the rate of pathologically confirmed unfavourable prostate cancers among Korean men who fulfilled the contemporary Epstein criteria for clinically insignificant prostate cancer. PATIENTS AND METHODS This was a retrospective study of 131 Korean men who underwent radical prostatectomy (RP) for clinically insignificant prostate cancer as defined by contemporary Epstein criteria. We assessed the percentage of unfavourable prostate cancer (pathological Gleason sum ≥7 and/or extraprostatic extension [EPE]) among these men and tried to identify useful predictors for such unfavourable tumour profiles using uni- and multivariate analyses. RESULTS Among 131 men with clinically insignificant prostate cancer, 40 (30.5%) had pathological Gleason ≥7 tumours after RP. Of these 40 men, four (3.1%) also had EPE on examination of RP specimen. All those who did not have Gleason score upgrading after RP had organ-confined disease from examination of RP specimen. Overall, 40 (30.5%) of the 131 men who fulfilled the contemporary Epstein criteria for clinically insignificant prostate cancer before RP had pathologically unfavourable disease. Among our patients, no significant preoperative predictor of pathologically unfavourable disease was identified using uni- and multivariate analyses. CONCLUSION Our results showed that a significant proportion of contemporary Korean patients who meet all the conditions of the contemporary Epstein criteria for prediction of clinically insignificant prostate cancer might actually harbour prostate cancer with unfavourable pathological features. Such findings should be considered when treatment options are contemplated based upon the Epstein criteria among Asian patients.

A series of waterborne polyurethane (WBPU)/clay nanocomposite coating materials were prepared by prepolymer process with different clay contents (0–2 wt %). The study investigated surface structure as well as water resistance, thermal, mechanical, and water vapor permeability (WVP) of composite materials as a function of clay contents. The glass transition temperature of composite materials was higher than pristine WBPU and also increased with increasing clay contents. Thermal stability, and water resistance of the nanocomposite films also increased, when compared with pristine WBPU, and these properties increased with an increase in clay content. The maximum tensile strength was found with optimum clay content (1 wt %) of composite films. The WVP of coated nylon fabrics depend on the clay content and temperatures. The rate (%) of WVP of coated nylon fabrics decreased with increasing clay content at a fixed temperature. However, at a fixed clay content the WVP increased with the increase of temperatures. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

A series of random copolymers, composed of 1H,1H-perfluorooctyl methacrylate (FOMA) and 2-dimethylaminoethyl methacrylate (DMAEMA) were prepared as stabilizers for the dispersion polymerization of methyl methacrylate in supercritical CO 2 (scCO 2 ). Free-flowing, spherical poly(methyl methacrylate) (PMMA) particles were produced in high yield by the effective stabilization of poly(FOMA-co-DMAEMA) containing 34-67 w/w % (15-41 m/m %) FOMA structural units. Less stabilized but micron-sized discrete particles could be obtained even with 25 w/w % (10 m/m %) FOMA stabilizer. The result showed that the composition of copolymeric stabilizers had a dramatic effect on the size and morphology of PMMA. The particle size was controllable with the surfactant concentration. The effect of the monomer concentration and the initial pressure on the polymerization was also investigated. The dry polymer powder obtained from dispersion polymerization could be redispersed to form stable aqueous latexes in an acidic buffered solution (pH = 2.1) by an electrostatic stabilization mechanism due to the ionization of DMAEMA units in the stabilizer.

In the stereocomplex between enantiomeric poly(l-lactide) (I-PLA) and poly(d-lactide), crystallites formed as a result of stereocomplexation, equimolar I- and d-lactide unit sequences are packed side by side. The stereocomplex exhibits a melting temperature higher by about 50 °C than that of each homopolymer. In this study, we attempt to obtain further insight into the stereocomplex-induced surface structure of enantiomeric PLA blend films. The design of the blend systems is based on principles of surface segregation of multicomponent polymeric systems with a low surface energy, triblock copolymer (l-PLA-b-PDMS-b-l-PLA) of l-PLA and poly(dimethyl siloxane). (l-PLA-b-PDMS-b-l-PLA/l-PLA) blend films showed the surface segregation of PDMS, regardless of blend composition while the surface composition of PDMS in the (l-PLA-b-PDMS-b-l-PLA/d-PLA) blend films was strongly depended on blend composition or a degree of complexation. These results are likely due to strong interaction between d- and l-lactide unit sequences, which prevents the surface segregation of PDMS.

The thiophene-based copolymers (poly)3TA-co-3HT)-1 and poly(3TA-co-3HT)-2) as hole conducting materials on the dye-sensitized solar cells (DSSCs) were synthesized. In order to increase the solubility and the interface absorption of the copolymers onto nanoporous TiO2 layer in the DSSC device, two different kinds of thiophene monomers were used hexyl and with substituted carboxyl groups. The compositions, structures, and thermal properties of these copolymers were characterized. The photovoltaic performances of the SnO2:F/TiO2/dye/polymer/Pt devices using the thiophene-based copolymers as hole conducting materials were investigated using a solar simulator at AM1.5. These photovoltaic results were compared with SnO2:F/TiO2/dye/polymer/Pt devices using the thiophene-based homopolymer by the effects of the interface adsorption on their substituted groups. Copyright © 2006 John Wiley & Sons, Ltd.

Interchain crosslinking in a grafted low-density polyethylene and millable polyurethane blend is reported. The interchain crosslinking was studied by torque rheometry and IR spectra. The mechanism of interchain crosslinking was suggested based on the IR spectra. Interchain crosslinking improves thermal stability, which was measured by differential scanning calorimetry. Tensile strength increased but the swelling coefficient decreased with increased interchain crosslinking. The degree of interchain crosslinking is higher for the glycidyl acrylate grafted sample than for the maleic anhydride grafted sample.

Poly(vinyl alcohol) (PVA)/clay nanocomposites were synthesized using the solution intercalation method. Na ion-exchanged clays [Na+–saponite (SPT) and Na+–montmorillonite (MMT)] and alkyl ammonium ion-exchanged clays (C12–MMT and C12OOH–MMT) were used for the PVA nanocomposites. From the morphological studies, the Na ion-exchanged clay is more easily dispersed in a PVA matrix than is the alkyl ammonium ion-exchanged clay. Attempts were also made to improve both the thermal stabilities and the tensile properties of PVA/clay nanocomposite films, and it was found that the addition of only a small amount of clay was sufficient for that purpose. Both the ultimate tensile strength and the initial modulus for the nanocomposites increased gradually with clay loading up to 8 wt %. In C12OOH–MMT, the maximum enhancement of the ultimate tensile strength and the initial modulus for the nanocomposites was observed for blends containing 6 wt % organoclay. Na ion-exchanged clays have higher tensile strengths than those of organic alkyl-exchanged clays in PVA nanocomposites films. On the other hand, organic alkyl-exchanged clays have initial moduli that are better than those of Na ion-exchanged clays. Overall, the content of clay particles in the polymer matrix affect both the thermal stability and the tensile properties of the polymer/clay nanocomposites. However, a change in thermal stability with clay was not significant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3208–3214, 2003

The rate of enzymatic degradation of surface-modified microbial polyesters, poly[(R)-3-hydroxybutyrate] and poly[(R)-3-hydroxybutyrate-co-3-hydroxyvalerate], was studied. The plasma treatments were carried out in a CF 3 H or O 2 environment. It was found that the CF 3 H plasma-treated polyesters exhibited significant retardation of enzymatic erosion because of the surface fluorocarbon groups induced by CF 3 H plasma. These surface fluorocarbon groups act as retardants on enzymatic degradation due to increased hydrophobicity and of the inactivity of enzymes. However, the increased surface hydrophilicity of polyesters induced by O 2 plasma results in no significant acceleration of the enzymatic erosion, which may be due to the thin modified layer.

Morphological changes of solution- grown poly[(R)-3-hydroxybutyrate] lamellar crystals during heating were directly investigated by atomic force microscopy. The thickening of lamellar crystals was further visualized by enzymatic degradation of lessordered crystal regions in thermally treated lamellar crystals. The morphological changes of lamellar crystals induced by thermal treatment are due to recrystallization.

In this work, blends of poly(butylene terephthalate) (PBT) and linear low-density polyethylene (LLDPE) were prepared. LLDPE was used as an impact modifier. Since the system was found to be incompatible, compatibilization was sought for by the addition of the following two types of functionalized polyethylene: ethylene vinylacetate copolymer (EVA) and maleic anhydride-grafted EVA copolymer (EVA-g-MAH). The effects of the compatibilizers on the rheological and mechanical properties of the blends have been also quantitatively investigated. The impact strength of the PBT–LLDPE binary blends slightly increased at a lower concentration of LLDPE but increased remarkably above a concentration of 60 wt % of LLDPE. The morphology of the blends showed that the LLDPE particles had dispersed in the PBT matrix below 40 wt % of LLDPE, while, at 60 wt % of LLDPE, a co-continuous morphology was obtained, which could explain the increase of the impact strength of the blend. Generally, the mechanical strength was decreased by adding LLDPE to PBT. Addition of EVA or EVA-g-MAH as a compatibilizer to PBT–LLDPE (70/30) blend considerably improved the impact strength of the blend without significantly sacrificing the tensile and the flexural strength. More improvement in those mechanical properties was observed in the case of the EVA-g-MAH system than for the EVA system. A larger viscosity increase was also observed in the case of the EVA-g-MAH than EVA. This may be due to interaction of the EVA-g-MAH with PBT. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 989–997, 1999

The Δχ effect on the miscibility of polymer blends prepared by solution-casting has been investigated using the mixture of poly(methyl methacrylate)(PMMA) with poly(vinyl acetate) (PVAc). The PMMA/PVAc blends have been prepared by casting from eleven different solutions. The Δχ effect of the solution–cast PMMA/PVAc blends was discussed in terms of Hansen's specified solubility parameters. It was found that the miscibility of the blends could be defined mainly by the solubility parameter contributed by the hydrogen–bonding of a solvent.