Ultrasound in urodynamics

Recent developments of ultrasound imaging have contributed much to the understanding of urodynamics in patients with lower urinary tract symptoms (LUTS). These include ultrasound estimated bladder weight (UEBW), transrectal power Doppler imaging of the prostate and transrectal ultrasonography during voiding (voiding TRUS). UEBW, which is obtained by measuring the thickness of the anterior bladder wall using a 7.5 MHz probe, represents well the degree of bladder hypertrophy caused by obstruction. This parameter is, accordingly, of clinical use in the evaluation of obstruction. The UEBW predicted the presence of obstruction as determined by pressure-flow study with a diagnostic accuracy of 73%. Transrectal power Doppler imaging of the prostate has made it easy to detect prostatic vessels and furthermore to obtain their resistive index (RI). Accumulating data suggest strongly that RI reflects the intraprostatic pressure. More interestingly, RI decreases significantly during voiding in normal subjects but not in patients with benign prostatic hyperplasia. Thus, this method is of particular use in monitoring noninvasively the dynamic change in intraprostatic pressure during voiding. Voiding TRUS makes it possible to monitor the movement of not only the posterior urethra but also the prostate during voiding. Based on our recent study, the anterior fibromuscular stroma (AFMS) seems to contract to open the urethra. Although the physiological function of the AFMS in the prostate remains unknown, AFMS may play a significant role in normal micturition. Due to its noninvasiveness and ease of application, ultrasound imaging would play a vital role in the diagnostic process for patients with LUTS in future.     

The dawn of computer-assisted robotic osteotomy with ytterbium-doped fiber laser

Currently, laser radiation is used routinely in medical applications. For infrared lasers, bone ablation and the healing process have been reported, but no laser systems are established and applied in clinical bone surgery. Furthermore, industrial laser applications utilize computer and robot assistance; medical laser radiations are still mostly conducted manually nowadays. The purpose of this study was to compare the histological appearance of bone ablation and healing response in rabbit radial bone osteotomy created by surgical saw and ytterbium-doped fiber laser controlled by a computer with use of nitrogen surface cooling spray. An Ytterbium (Yb)-doped fiber laser at a wavelength of 1,070 nm was guided by a computer-aided robotic system, with a spot size of 100 μm at a distance of approximately 80 mm from the surface. The output power of the laser was 60 W at the scanning speed of 20 mm/s scan using continuous wave system with nitrogen spray level 0.5 MPa (energy density, 3.8?×?10⁴ W/cm²). Rabbits radial bone osteotomy was performed by an Yb-doped fiber laser and a surgical saw. Additionally, histological analyses of the osteotomy site were performed on day 0 and day 21. Yb-doped fiber laser osteotomy revealed a remarkable cutting efficiency. There were little signs of tissue damage to the muscle. Lased specimens have shown no delayed healing compared with the saw osteotomies. Computer-assisted robotic osteotomy with Yb-doped fiber laser was able to perform. In rabbit model, laser-induced osteotomy defects, compared to those by surgical saw, exhibited no delayed healing response.     

Liquid diet induces memory impairment accompanied by a decreased number of hippocampal neurons in mice

It is suggested that masticatory dysfunction affects the central nervous system; however, the underlying mechanism remains unknown. Brain‐derived neurotrophic factor (BDNF) and its receptor, TrkB, are known to play important roles in memory and learning. In this study, we examined the effects of mastication on memory, the expression levels of BDNF and TrkB, and the number of neurons in the hippocampus of mice. Male C57 BL/6J mice (3 weeks old) were randomly divided into the control group (N = 7) fed chow pellets and the experimental group (N = 7) fed a liquid diet, which reduces mastication during eating. At 14 weeks of age, we performed a passive avoidance test and found that memory and learning ability were impaired in the experimental group compared with the control group. After the behavioral experiment, brains were harvested and analyzed morphologically and biochemically. In the hippocampus of the experimental group, the expression levels of BDNF were significantly higher, whereas those of TrkB were lower than those of the control group. In the cerebral cortex, these levels remained unchanged between the two groups. The ratio of phospho‐p44/42 ERK/pan ERK, a downstream molecule of BDNF/TrkB signaling, in the experimental group was significantly lower than that of the control group in the cortex and hippocampus. The number of pyramidal neurons in the hippocampus was lower in the experimental group than in the control group. These findings suggest that reduced mastication induced by a liquid diet in early childhood may impair memory and learning ability, accompanied by neuronal loss in the hippocampus. © 2014 Wiley Periodicals, Inc.     

Flame retardance-donated lignocellulose nanofibers (LCNFs) by the Mannich reaction with (amino-1,3,5-triazinyl)phosphoramidates and their properties

Nitrogen/phosphorus-containing melamines (NPCM), a durable flame-retardant, were prepared by the successive treatment of ArOH (Ar = Br_nC₆H_5−n, n = 0, 1, 2, and 3) with POCl₃ and melamine monomer. The prepared flame-retardants were grafted through the CH₂ unit to lignocellulose nanofibers (LCNFs) by the Mannich reaction. The resulting three-component products were characterized using FT-IR (ATR) and EA. The thermal behavior of the NPCM-treated LCNF fabric samples was determined using TGA and DSC analyses, and their flammability resistances were evaluated by measuring their Limited Oxygen Index (LOI) and the UL-94V test. A multitude of flame retardant elements in the fabric samples increased the LOI values as much as 45 from 20 of the untreated LCNFs. Moreover, the morphology of both the NPCM-treated LCNFs and their burnt fabrics was studied with a scanning electron microscope (SEM). The heat release lowering effect of the LCNF fabric against the water-based paint was observed with a cone calorimeter. Furthermore, the mechanical properties represented as the tensile strength of the NPCM-treated LCNF fabrics revealed that the increase of the NPCM content in the PP-composites led to an increased bending strength with enhancing the flame-retardance.

LCNFs were grafted with nitrogen/phosphorus-containing melamines to achieve potent flame-retardance and converted to PP-composites of improved mechanical properties.     

Tumor length and location of cancer on biopsy predict for side specific extraprostatic cancer extension

PURPOSE: We studied preoperative variables in a contemporary series of men who underwent nonnerve sparing radical prostatectomy in an effort to establish criteria that would predict side specific extraprostatic extension (EPE) of cancer. MATERIALS AND METHODS: We reviewed the records of 430 patients who underwent radical prostatectomy for localized prostate cancer with no prior therapy between 1996 and 1998, and for whom we had at least sextant biopsy information. We evaluated biopsy data (Gleason score, maximum length of cancer in positive cores, percent of cancer per involved core, proportion of positive biopsy cores, tumor location and number of positive biopsy cores) and correlated these findings with EPE at the neurovascular bundle and posterior lateral (NVB/PL) region. RESULTS: We found that a higher number of positive cores, a higher biopsy Gleason score on a side, a positive core at the basal region, 50% or greater tumor in the core or a maximum tumor length of 7 mm or greater increased the likelihood that EPE was present at the NVB/PL region on the corresponding side of the prostate. On multivariate analysis maximum tumor length 7 mm or greater and positive basal core location were the strongest independent predictors of EPE at the NVB/PL region on a given side (p <0.0001 and 0.002, respectively). CONCLUSIONS: Excluding any patient with 1 positive biopsy core with a maximum tumor length of 7 mm or greater plus a positive basal core of any tumor length and grade can decrease the risk of EPE at the NVB/PL region to approximately 10%.     

Prognostic significance of serum osteoprotegerin levels in patients with bladder carcinoma

BACKGROUND: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) plays an important role in the process of lymphocyte-mediated cytotoxicity against malignant cells. Osteoprotegerin (OPG) is a soluble decoy receptor for TRAIL, and circulating OPG has been implicated in the protection of cells from TRAIL-mediated apoptosis. Thus, OPG may protect tumor cells from lymphocyte-mediated cytotoxicity and, as a result, contribute to tumor progression. In the current study, the authors investigated this hypothesis in patients with bladder carcinoma. METHODS: Serum OPG levels for 185 patients with bladder carcinoma were determined using an enzyme-linked immunosorbent assay. These levels then were assessed for potential correlations with various disease characteristics and outcome measures. RESULTS: The mean serum OPG concentration in patients with bladder carcinoma was approximately 3 times greater than the mean concentration in healthy individuals, and among patients with bladder carcinoma, higher tumor stage and grade were found to be associated with increased serum OPG levels. Within the subpopulation of patients with superficial bladder carcinoma, after a follow-up period of 5 years, those who had low serum OPG levels tended to have a longer postoperative tumor-free interval compared with those who had high serum OPG levels. Furthermore, among patients with muscle-invasive bladder carcinoma, the 5-year disease-specific survival rate was greater for those who had low serum OPG levels than for those who had high serum OPG levels. CONCLUSIONS: To the authors' knowledge, the current study is the first to demonstrate that serum OPG concentration is correlated with both tumor stage and tumor grade and that elevated serum OPG levels are predictive of early recurrence in patients with bladder carcinoma. These findings suggest that serum OPG concentration may have utility as a prognostic parameter in this setting.     

Clinical efficacy of prostate cancer detection using power doppler imaging in American and Japanese men

PURPOSE: The aim of this study was to compare the detection rates of tumor vascular flow as measured by power Doppler imaging (PDI) in 2 populations and to determine whether PDI can reduce the number of unnecessary prostate biopsies in men with serum prostate-specific antigen (PSA) concentrations less than 10.1 ng/ml. METHODS: The patient populations were Japanese (group 1) and American (group 2) men with either serum PSA concentrations of 4.1-10.0 ng/ml or abnormal findings on digital rectal examination (DRE) plus PSA concentrations less than 4.1 ng/ml. We compared the overall diagnostic accuracy of DRE, gray-scale transrectal sonography (TRUS), and PDI between the 2 groups. RESULTS: In total, 275 men were studied, 154 in group 1 and 121 in group 2. Cancer was identified in 27% of men in group 1 and in 60% of group 2. Men with cancer in both groups differed significantly in age, peripheral zone volume, and mean number of positive biopsy cores. The sensitivity and specificity of PDI in group 2 were significantly inferior to those in group 1. The negative predictive value (NPV) of PDI was significantly higher for group 1 than for group 2. The NPV of PDI in group 1 was equivalent to that for the combination of DRE and TRUS, whereas the NPV for PDI in group 2 was significantly inferior to that of DRE and TRUS.CONCLUSIONS: Tumor vascularity could be detected by PDI more effectively in Japanese men with cancer than in American men with cancer. We hypothesize that this difference was a result of larger cancer volumes and smaller prostates in the Japanese men. PDI did not provide any performance advantage over DRE and TRUS in avoiding unnecessary biopsies.