Hollow Hafnium Oxide (HfO2) Fibers: Using an Effective Combination of Sol-Gel, Electrospinning, and Thermal Degradation Pathway.

In recent years, hafnium oxide (HfO2) has gained increasing interest because of its high dielectric constant, excellent thermal stability, and high band gap. Although HfO2 bulk and film materials have been prepared and well-studied, HfO2 fibers, especially hollow fibers, have been less investigated. In this study, we present a facile preparation method for HfO2 hollow fibers through a unique integration of the sol-gel process and electrospinning technique. Initially, polystyrene (PS) fibers are fabricated by using electrospinning, followed by dipping in a HfO2 precursor solution, resulting in HfO2-coated PS fibers. Subsequent thermal treatment at 800 °C ensures the selective pyrolysis of the PS fibers and complete condensation of the HfO2 precursors, forming HfO2 hollow fibers. Scanning electron microscopy (SEM) characterizations reveal HfO2 hollow fibers with rough surfaces and diminished diameters, a transformation attributed to the removal of the PS fibers and the condensation of the HfO2 precursors. Our study also delves into the influence of precursor solution molar ratios, showcasing the ability to achieve smaller HfO2 fiber diameters with reduced precursor quantities. Validation of the material composition is achieved through thermogravimetric analysis (TGA) and energy-dispersive spectroscopy (EDS) mapping. Additionally, X-ray diffraction (XRD) analysis provides insights into the crystallinity of the HfO2 hollow fibers, highlighting a higher crystallinity in fibers annealed at 800 °C compared with those treated at 400 °C. Notably, the HfO2 hollow fibers demonstrate a water contact angle (WCA) of 38.70 ± 5.24°, underscoring the transformation from hydrophobic to hydrophilic properties after the removal of the PS fibers. Looking forward, this work paves the way for extensive research on the surface properties and potential applications of HfO2 hollow fibers in areas such as filtration, energy storage, and memory devices.

Photo-Healable Fabrics: Achieving Structural Control via Photochemical Solid-Liquid Transitions of Polystyrene/Azobenzene-Containing Polymer Blends.

While polymer fabrics are integral to a wide range of applications, their vulnerability to mechanical damage limits their sustainability and practicality. Addressing this challenge, our study introduces a versatile strategy to develop photohealable fabrics, utilizing a composite of polystyrene (PS) and an azobenzene-containing polymer (PAzo). This combination leverages the structural stability of PS to compensate for the mechanical weaknesses of PAzo, forming the fiber structures. Key to our approach is the reversible trans-cis photoisomerization of azobenzene groups within the PAzo under UV light exposure, enabling controlled morphological alterations in the PS/PAzo blend fibers. The transition of PAzo sections from a solid to a liquid state at a low glass transition temperature (Tg ∼ 13.7 °C) is followed by solidification under visible light, thus stabilizing the altered fiber structures. In this study, we explore various PS/PAzo blend ratios to optimize surface roughness and mechanical properties. Additionally, we demonstrate the capability of these fibers for photoinduced self-healing. When damaged fabrics are clamped and subjected to UV irradiation for 20 min and pressed for 24 h, the mobility of the cis-form PAzo sections facilitates healing while retaining the overall fabric structure. This innovative approach not only addresses the critical issue of durability in polymer fabrics but also offers a sustainable and practical solution, paving the way for its application in smart clothing and advanced fabric-based materials.

Predictive factors of lower calyceal stone clearance after extracorporeal shockwave lithotripsy (ESWL): the impact of radiological anatomy.

BACKGROUND: This study was carried out to determine whether or not there is a significant relationship between the radiologic anatomy of the lower calyx, as seen on preoperative intravenous urography (IVU), and the outcome of stone clearance after extracorporeal shockwave lithotripsy (ESWL) for lower renal calyceal stones. METHODS: Between June 1998 and April 2007, 112 patients with a solitary lower renal calyceal stone measuring 20 mm or less in size were enrolled in this retrospective study. Pretreatment IVU was reviewed for measuring the anatomical predictors, such as lower pole infundibular length, infundibular width (IW) and infundibulopelvic angle, while the stone location and size were determined on plain abdominal X-ray. All patients were treated with ESWL using a Siemens Lithostar Plus lithotriptor and were followed-up for the outcome of stone clearance 3 months after ESWL with plain abdominal X-ray films and ultrasonography. RESULTS: Three months after ESWL, only 49 (43.7%) patients were stone-free. Under multivariate analysis with logistic regression, smaller stone size (10 mm or less, p = 0.005) and greater IW (4 mm or more, p = 0.029) were significant favourable predictors for better stone clearance. CONCLUSION: In addition to the influence of stone size, lower pole anatomy, especially IW, has a significant impact on stone clearance for lower calyceal stone after ESWL.

Complications of pure transperitoneal laparoscopic surgery in urology: the Taipei Veterans General Hospital experience.

BACKGROUND: We present our experience of complications of pure transperitoneal laparoscopic surgery in urology at Taipei Veterans General Hospital. METHODS: Between September 2003 and March 2006, 185 laparoscopic urologic operations were performed, consisting of 70 nephrectomies (36 radical, 17 partial, 11 simple, 6 donor), 28 adrenalectomies, 28 nephroureterectomies, 22 radical prostatectomies, 17 ureterolithotomies, 6 radical cystectomies, 5 pyeloplasties, 2 renal cyst unroofings, 2 nephropexies and 5 other operations. We reviewed the database of the patients to evaluate the complications and analyze factors related to laparoscopic surgeries. RESULTS: A total of 25 patients had 26 complications (14.1%, major in 4, minor in 22). The complications were categorized into intraoperative and postoperative complications in 10 and 16 patients, respectively. The mortality rate was 0%. The conversion rate was 0.54% (1 patient). The re-operation rate was 1.08% (2 patients). The most common intraoperative complication was vascular injury (5 patients). The incidence of complication was related to the difficulty level of operation. No statistically significant differences were found between complication rate and patient age, patient body mass index or the American Society of Anesthesiologist score. CONCLUSION: The complications of laparoscopic urologic surgeries are strongly correlated with the operative difficulties. In spite of elevated complication rates in difficult surgeries, the major complication rate in this study was very low. As the laparoscopic surgeries in urology involve more and more technique-dependent difficult fields, documentation and analysis of experience of complications is important for the development of this surgical modality.

Urothelial carcinoma of the urinary bladder in young adults--clinical experience at Taipei Veterans General Hospital.

BACKGROUND: The clinical behavior and prognosis of bladder cancer in young patients is not well defined. The aim of this study was, therefore, to evaluate the clinical behavior, pathologic characteristics and prognosis of urothelial carcinoma of the urinary bladder in young adults. METHODS: We retrospectively reviewed records from 30 young patients (23 males, 7 females; age < or = 40 years) with urothelial carcinoma of the urinary bladder who had been treated in our hospital between May 1990 and October 2003. Data were analyzed by the Kaplan-Meier method to assess disease recurrence and survival. RESULTS: The mean age at diagnosis was 34.3 +/- 5 years (range, 22-40 years). Fifteen patients presented with pTa, 9 with pT1, 4 with pT2, 1 with pT3, and 1 with pT4. Twenty-six patients (87.2%) had low-grade bladder cancer, and the other 4 had high-grade disease. The most frequent initial presenting symptom was gross hematuria. The mean postoperative follow-up period was 72.8 months (range, 4-149 months). Fifty percent of superficial bladder cancers recurred a mean of 10.7 months (range, 3-68 months) after operation. One patient died from invasive bladder cancer after radical cystectomy, and 1 died from superficial bladder cancer due to tumor progression. The 5-year cancer-specific survival rate was 95.2% for superficial cancer and 83.3% for invasive cancer. The overall survival rate was 93.3%. CONCLUSION: Urothelial carcinoma of the urinary bladder in young adults is usually associated with low grade and low stage. Invasive bladder cancer had no worse a survival rate than superficial bladder cancer.

Lower urinary tract symptoms and uroflow in a community-based sample of Taiwanese men.

BACKGROUND: Inter-cultural difference in the prevalence of lower urinary tract symptoms (LUTS) has been recognized. The purpose of present study was to evaluate the prevalence of LUTS and the correlation between symptoms with age and urinary flow rate in a community-based sample of Taiwanese men. METHODS: Invitation letters were sent out to 4,488 men > or = 40 years old living in Ling-Ya District, Kaohsiung City. All responders were scheduled for thorough history taking, International Prostate Symptom Score (IPSS) assessment, digital rectal examination, serum prostatic specific antigen (PSA) and uroflow determinations. The correlation of IPSS with age, PSA levels and urinary flow rate were evaluated. RESULTS: A total of 306 men (6.8%) accepted our invitation; 207 of them had validated data for analysis. The confidence interval was 6.79 at 95% confidence level. Twenty-one men (10.1%) had serum PSA > 4 ng/ml. The median PSA increased with advancing age (p = 0.001). Severe symptoms were reported by 9.7%, while 40.1% reported moderate symptoms. The percentage of men with IPSS > or = 8 increased withage (p < 0.001). There was a positive correlation between IPSS and age (r = 0.380). Negative correlation between IPSS and voided volume (r = -0.255), maximal flow rate (r = -0.363), and mean flow rate (r = -0.401) were also noted. CONCLUSIONS: In this community-based study, moderate to severe lower urinary tract symptoms were reported by 50% of assessable men over the age of 40 years. This prevalence was similar to that of Japanese but higher than those of American, French, and Scottish men. The IPSS was positively correlated with age, and negatively correlated with uroflow rate and voided volume. However, because of extremely low and uneven response rates among each age category, this data must be interpreted with caution.

Correlation between urinary tract pure stone composition and stone morphology on plain abdominal film.

BACKGROUND: Crystallographic composition of urinary tract stone varies in several chemical groups and determines the degree of fragmentation to extracorporeal shock wave lithotripsy (ESWL) which has been widely used for the treatment of renal and ureteral calculi. Visual prediction of stone composition by its morphology from plain radiograph may provide a simple method and clinical hint to decide therapeutic modalities. A prospective study was designed to determine the correlation of stone composition with its radiographic morphology. METHODS: One hundred patients of urolithiasis with passage of stone fragments (after ESWL, surgical lithotomy or endoscopic lithotripsy) analyzed as pure stone by infrared spectrometry were reviewed by plain abdominal film to classify their morphology, location and size. Five experienced surgeons familiar with the radiographic patterns of different types of pure stones were invited to predict the stone composition on plain abdominal film. RESULTS: Five different patterns of radiographic appearances of the stones were identified. Calcium oxalate monohydrate referred to the smooth-shaped and homogeneous ones with denser opacity. Calcium oxalate dihydrate referred to those smaller ones that had irregular margin with stippled border and were less dense. Calcium phosphate (CaP) had moderate density and size without significant figures. Struvite meant staghorn stone; usually bilateral. Uric acid referred to those being radiolucent, slightly opacified, and in large size. The 5 surgeons achieved an overall accuracy of 27.4%. There was no obvious relations between accuracy and location or size of the stones. CaP stone was the most likely to be misclassified, and achieved only 20% accuracy. CONCLUSIONS: Different stone composition showed grossly specific radiographic appearances, but clinical test revealed poor correct rate in prediction of stone composition from plain abdominal film. The results of our study suggest that prediction of stone component based on stone morphology on plain abdominal film may not be accurate enough. Patient's clinical information and other laboratory data should be considered while interpreting plain abdominal film for better treatment choice of urolithiasis.

Experience of surgical treatment of peyronie's disease with deep dorsal venous patch graft in Taiwanese men.

BACKGROUND: Using venous graft to repair the defect of tunica cavernosal plaque incision has been a mainstay of surgical intervention for Peyronie's disease. The greater saphenous vein is generally believed to be the graft of choice. However, the increased discomfort as well as the chance of morbidity in harvesting saphenous vein is occasionally reported. The other alternative for donor vein graft is from the deep dorsal vein of the penis. The major concern in using the deep dorsal vein is its lack of thickness and its limitation in the size to cover the defect. This study is to assess the feasibility of the deep dorsal vein graft in repairing the defect after plaque incision for Peyronie's disease in Taiwanese men. METHODS: Twenty-four men of Peyronie's disease were included from 1992 to 2001 in our institution. The mean age was 56.3 years (range 51-70). All patients underwent tunica plaque incision and deep dorsal vein patch grafting. The mean followup was 2.6 years (range 1-8). Penile straightness, potency status and possible complications after this procedure were evaluated during the followup. RESULTS: The location of the plaque(s) was at left lateral penile shaft for 10 patients, right lateral for 6, ventral for 5 and dorsal for 3. The mean curvature angle was 45 degrees (range 35 degrees - 75 degrees). The penis became straight in 23 out of 24 (96%) of the patients after the operation, while the other one had a residual curvature about 20 degrees. Twenty-three patients (96%) remained similar potency as in preoperative status. The other one had less rigidity but can still accomplish successful intercourse. Three patients experienced sensation change at the glans, and it recovered gradually within 8 months. They were all satisfied with the operation. CONCLUSIONS: Deep dorsal vein patch harvested from patients' own penis had a satisfied outcome from a Taiwanese cohort. For smaller Peyronie's defect, especially in Asian men, deep dorsal vein patch is a graft of choice.

Chyluria--experience of Taipei Veterans General Hospital.

BACKGROUND: Chyluria is caused by rupturing of lymphatic varices into the pyelocaliceal system. Although Chyluria is rare in western countries, it is not uncommon in Asia. We would like to present the experience of diagnosis, evaluation and treatment of chyluria in Taipei Veterans General Hospital. METHODS: From 1973 to 1999, a total of 30 patients with chyluria were reviewed. All had the chief complaint of milky white urine passage. They were investigated by multiple workup modalities including computed tomography, intravenous urography, lymphangiography, and cystoscopy. Fifteen cases received 1% silver nitrate instillation and 4 cases underwent nephrolysis either as primary or salvage treatment. RESULTS: Lymphangiography was performed in 24 of the 30 cases and responsible causes of chyluria were noted in 21. They were followed up for at least 12 months in 9 patients treated by intrarenal pelvic instillation of silver nitrate and 3 by nephrolysis, respectively. Recurrence was found in 1 patient (11.1%) receiving silver nitrate only and no significant adverse effect was noted. CONCLUSIONS: Lymphangiography is the most powerful diagnostic tool. Intrarenal silver nitrate instillation is a safe and effective management of chyluria.

Lymphangioma of male exogenital organs.

Lymphangioma manifesting in the genitourinary tract is an uncommon disease. Cystic lymphangioma is a congenital lymphatic hamartoma known as lymphatic malformation. Herein we report 2 cases of lymphangioma of male exogenital organs. After complete excision of the tumor and subsequent follow-up for 6 months, both of them were free of recurrence. Ultrasonography and computed tomography scans are very useful in the differential diagnosis of this cystic disease.

Antiandrogen-associated hepatotoxicity in the management of advanced prostate cancer.

BACKGROUND: Antiandrogens available for patients with advanced prostate cancer are reported to cause hepatotoxicity. The aim of this study is to investigate the antiandrogen-associated hepatotoxicity in patients with advanced prostate cancer. METHODS: By retrospective charts review, 229 patients (47-89 years old) with advanced prostate cancer treated by total androgen blockade (TAB) with bilateral orchiectomy or LHRH (luteinizing hormone-releasing hormone) analogues plus antiandrogen, or antiandrogen-radiotherapy were enrolled in this study. There were 124 patients taking flutamide 750 mg daily and 105 patients taking cyproterone acetate (CPA) 150 mg daily. Hepatotoxicity defined by the International Consensus Meeting in 1990 and Food and Drug Administration, USA was used to evaluate the hepatotoxicity (including serious hepatotoxicity). RESULTS: There was a higher occurrence of hepatotoxicity in patients taking flutamide (15.3%) than taking CPA (9.5%) (p = 0.034). The occurrence of serious hepatotoxicity of flutamide and CPA was 4.8% (6/124) and 3.8% (4/105), respectively. The mean latency period of hepatotoxicity for CPA was 4.8 +/- 2.0 months for flutamide and 5.8 +/- 1.9 months for CPA, respectively. The 2 groups made no significant difference of liver enzyme (mean maximal alanine aminotransaminase (ALT) and aspartate aminotransaminase (AST) = 284.2 +/- 99.3/300.6 +/- 58.5 U/L versus 341.8 +/- 67.1/301.6 +/- 80.5 U/L). All of the 19 patients (100%) and 9 of 10 patients (90%) with flutamide and CPA-induced hepatotoxicity got self-resolution after discontinuation of the antiandrogens. The average time of self-resolution is 4.5 +/- 3.1 months and 6.3 +/- 4.7 months for flutamide and CPA, respectively. Five patients of flutamide-induced and 2 patients of CPA-induced hepatotoxicity got resolution after changing to other antiandrogen. CONCLUSIONS: Flutamide and CPA appear to cause hepatotoxic effects in some patients. Discontinuation of the antiandrogens seems to be the resolution of hepatotoxicity. A change to other antiandrogen may be the alternative strategy to the antiandrogen-induced hepatotoxicity. The results of this study suggest that all patients received flutamide and CPA should be monitored carefully for signs and symptoms referable to hepatic injury to prevent the development of serious hepatic dysfunction.

Long-term efficacy and safety of sildenafil for patients with erectile dysfunction.

BACKGROUND: To investigate the long-term efficacy and safety of sildenafil for patients with erectile dysfunction (ED). METHODS: Between March 1999 and February 2001, a total of 3168 patients visited Taipei Veterans General Hospital for prescription of sildenafil. The follow-up period was 1-3 years. A questionnaire was designed for evaluation of efficacy and safety of sildenafil via telephone survey. RESULTS: Of the 3168 patients, 1414 were interviewed by telephone. Data from telephone questionnaires were successfully obtained in 1074 cases. Achievement of the first penile erection after sildenafil was reported in 58.8% of our patients. The distribution of the first doses was 0.6%, 8.5%, 81.9% and 90% for 12.5 mg, 25 mg, 50 mg and 100 mg, respectively. After administration of sildenafil, 72.1% men had successful intercourses "sometimes" or "always achieving vaginal penetration", and 72.3% had "slight difficulty" or "no difficulty" in maintaining of sexual intercourses. The "sometimes/most times/always" satisfaction accounted 63.9% and 62.8%, respectively for patients and partners. The global assessment of penile erection was improved in 58.6% of the patients. The sexual confidence of the patients was moderate, high and very high in 72.4% of the patients. Of the 434 patients who failed first penile erections, 400 (92.2%) were related to improper administration of sildenafil. Discontinuation of sildenafil in the last 3 months before telephone survey was found in 852 patients (80.2%). The causes of discontinuation were loss of efficacy in 51.6% of patients, lack of sexual desire in 8.8%, and chronic diseases in 8.2%. Spontaneous erection without sildenafil was claimed in 21.5% of the patients (most times in 9.5% and always in 12.0%). The rate of adverse events after taking sildenafil were 16.6%, and the most common adverse event was facial flushing (9.2%). CONCLUSIONS: The results of this study demonstrated that the efficacy of sildenafil was similar to the previous clinical trials. The adverse events after sildenafil were mild and tolerable. Recovery of complete or partial spontaneous erection was noted in some patients (21.5% in our study) after long-term usage of sildenafil.

Correlation between serum prostate specific antigen and prostate volume in Taiwanese men with biopsy proven benign prostatic hyperplasia.

PURPOSE: We studied the correlation between serum prostate specific antigen and the volume of different zones of the prostate in Taiwanese men with biopsy proven benign prostatic hyperplasia. MATERIALS AND METHODS: A total of 233 patients with a mean age of 71.4 years (range 42 to 89), serum prostate specific antigen less than 10 ng/ml and pathologically confirmed benign prostatic hyperplasia were enrolled in this study. Total prostate and transitional zone volumes were measured with transrectal ultrasonography. Peripheral zone volume was determined by subtracting transitional zone volume from total prostate volume. Correlations between patient age, total serum prostate specific antigen and the volume of each prostate zone were analyzed with the Pearson correlation coefficient. A linear regression model was used to determine the relationship between prostate specific antigen and prostate volume. The prostate specific antigen-prostate volume relationship in our patients was compared with published data on white and Japanese men. RESULTS: Age did not significantly correlate with serum prostate specific antigen and prostate volume. Serum prostate specific antigen significantly correlated with the volume of each prostate zone. After log transformation the Pearson correlation coefficient between total prostate specific antigen and the volume of the whole prostate gland, the transitional zone and the peripheral zone were 0.369, 0.377 and 0.272, respectively (p <0.001). Taiwanese men had lower prostate volume per unit prostate specific antigen comparing with white men, while the prostate specific antigen-total prostate volume relationship between Taiwanese and Japanese men was similar. CONCLUSIONS: In Taiwanese men with biopsy proven benign prostatic hyperplasia the volume of each prostate zone has significantly correlates with serum prostate specific antigen. The prostate specific antigen-total prostate volume relationship in Taiwanese men is different from that in white men. However, the prostate specific antigen-total prostate volume relationship between Taiwanese and Japanese men is similar.

E-cadherin expression in prostate adenocarcinomas in Chinese and its pathological correlates.

INTRODUCTION: We examined the E-cadherin expression in prostate adenocarcinomas in Chinese to correlate this immunohistochemical marker with histopathological features. MATERIALS AND METHODS: Primary adenocarcinomas from 122 radical prostatectomy specimens were stained using anti-E-cadherin (HECD-1) antibody. The association of E-cadherin expression with serum prostate-specific antigen (PSA), pathological stage and Gleason score was assessed by Kendall's tau-b test. RESULTS: Aberrant E-cadherin expression was identified in 79 tumors (64.8%). Abnormal E-cadherin expression did not correlate to serum PSA (p = 0.802), tumor stage (p = 0.684) and Gleason score (p = 0.385). CONCLUSIONS: The frequency of aberrant E-cadherin expression was higher in prostate adenocarcinomas of Chinese as compared to that reported in Caucasians. No association with pathological stage, Gleason score and serum PSA was identified.

The modulus of toughness of urinary calculi.

To improve the efficacy of extracorporeal shock wave lithotripsy (ESWL) treatment, it is desirable to identify the physical properties of urinary calculi could offer direct correlation with their fragilities during ESWL and thus could be used to guide treatment procedures for more effective stone fragmentation. Thirty stone specimens removed surgically were compressed by an axial testing system to measure the compressive strength and trace the stress-strain curve. Image analysis software SigmaScan (Jandel Co.) was used to calculate the area under the stress-strain curve, the modulus of toughness, for each stone. The values of compressive strength measured were similar to those reported by other researchers. The modulus of toughness of urinary calculi correlates with clinical representation of the stone fragility during ESWL. The modulus of toughness could be an index to evaluate the physical property of urinary calculi that could be used to guide treatment procedures for more effective stone fragmentation.