Lyotropic Boron Nitride Nanotube Liquid Crystals: Preparation, Characterization, and Wet-Spinning for Fabrication of Composite Fiber.

Microfiber fabrication via wet-spinning of lyotropic liquid crystals (LCs) with anisotropic nanomaterials has gained increased attention due to the microfibers' excellent physical/chemical properties originating from the unidirectional alignment of anisotropic nanomaterials along the fiber axis with high packing density. For wet-spinning of the microfibers, however, preparing lyotropic LCs by achieving high colloidal stability of anisotropic nanomaterials, even at high concentrations, has been a critically unmet prerequisite, especially for recently emerging nanomaterials. Here, we propose a cationically charged polymeric stabilizer that can efficiently be adsorbed on the surface of boron nitride nanotubes (BNNTs), which provide steric hindrance in combination with Coulombic repulsion leading to high colloidal stability of BNNTs up to 22 wt %. The BNNT LCs prepared from the dispersions with various stabilizers were systematically compared using optical and rheological analysis to optimize the phase behavior and rheological properties for wet-spinning of the BNNT LCs. Systematic optical and mechanical characterizations of the BNNT microfibers with aligned BNNTs along the fiber axis revealed that properties of the microfibers, such as their tensile strength, packing density, and degree of BNNT alignment, were highly dependent on the quality of BNNT LCs directly related to the types of stabilizers.

Metachronous anterior urethral metastasis of prostatic ductal adenocarcinoma / 고신대학교의과대학학술지

Prostate cancer is increasing in frequency in Korea. Among them, ductal adenocarcinoma (DCP) has a more aggressive and poor prognosis than acinar adenocarcinoma (ACP), despite its low incidence. Patients usually present with symptoms of lower urinary tract symptoms and hematuria due to increasing tumor mass within the lumen of the prostatic urethra, making diagnosis of DCP by the transrectal prostate biopsy difficult. DCP is often metastasized at the time of diagnosis. DCP is transferable to most other organs but the metastasis to the anterior urethra is rare. There is no doubt that localized DCP requires radical prostatectomy (RP) but the guidelines for adjuvant therapy after RP have not yet been established. Methods of the treatment are confounded by individual differences, and arriving at a consensus is challenging due to insufficient data. We report a case of DCP and urethral metastasis after RP, thus aiding in the determination of treatment guidelines.

Factors Influencing the Operative Approach to Renal Tumors: Analyses According to RENAL Nephrometry Scores

PURPOSE: To evaluate the relationship between RENAL nephrometry score (RNS) and operative approach for renal masses. MATERIALS AND METHODS: This study included 206 consecutive patients who underwent renal tumor surgery between January 2008 and October 2012. We divided the patients into four groups by surgical approach: open radical nephrectomy (ORN, 53 patients), laparoscopic radical nephrectomy (LRN, 83 patients), open partial nephrectomy (OPN, 31 patients), and laparoscopic partial nephrectomy (LPN, 39 patients). We retrospectively assessed the RNS for each surgery group and evaluated the relationship between this score and operative approach. RESULTS: The mean RNSs of the ORN, LRN, OPN, and LPN groups were 9.75, 8.35, 6.72, and 5.76, respectively. When the RNS was analyzed according to nephron-sparing, the mean RNSs of the RN groups (ORN and LRN) and the PN groups (OPN and LPN) were significantly different (8.89 and 6.09, respectively; p<0.001). All the individual components of the RNS were significantly different between RN and PN. In the RN groups, the criteria for open versus laparoscopic surgery were based on tumor size ('R' score=2.43 for open, 1.54 for laparoscopic, p<0.001) and tumor location relative to the polar line ('L' score=2.55 for open, 2.09 for laparoscopic, p=0.006). In the PN groups, the criteria for open or laparoscopic surgery were based only on exophytic/endophytic property ('E' score=1.87 for open, 1.41 for laparoscopic, p=0.046). CONCLUSIONS: The RNS was significantly different in all surgery groups. The decision to take a laparoscopic approach was primarily influenced by the R and L scores for RN and by the E score for PN.

Squamous Cell Carcinoma of the Suprapubic Cystostomy Tract With Bladder Involvement

Herein we report a case of a squamous cell carcinoma of a well-healed suprapubic cystostomy tract scar involving the bladder mucosa in a 56-year-old man. He presented with a spontaneous suprapubic urinary leak from a suprapubic cystostomy tract scar. He had a history of urethral stricture and failed urethroplasty. Preoperative cystoscopy suggested a bladder mass. Transurethral biopsy of the bladder mass revealed a squamous cell carcinoma confined to the suprapubic cystostomy tract involving the bladder mucosa. The patient died 6 months after the start of radiation therapy after lung metastasis and pneumonia.