Pruritus in hemodialysis patients: Results from the Japanese Dialysis Outcomes and Practice Patterns Study (JDOPPS)

Pruritus affects many patients undergoing hemodialysis (HD). In this study, pruritus and its relationship to morbidity, quality of life (QoL), sleep quality, and patient laboratory measures were analyzed in a large sample of Japanese patients undergoing HD. Severity of patient‐reported pruritus symptoms experienced during a 4‐week period was collected from 6480 Japanese patients undergoing HD in three phases of the Dialysis Outcomes and Practice Patterns Study (DOPPS; 1996–2008; 60–65 study facilities/phase). Adjusted linear and logistic regressions were used to identify associations of pruritus with treatment parameters and QoL outcomes. Adjusted Cox regressions examined the influence of pruritus severity on mortality. Moderate to extreme pruritus was experienced by 44% of prevalent patients undergoing HD in the Japanese Dialysis Outcomes and Practice Patterns Study. Many patient characteristics were significantly associated with pruritus, but this did not explain the large differences in pruritus among facilities (20–70%). Pruritus was slightly less common in patients starting HD than in patients on dialysis >1 year. Patients with moderate to extreme pruritus were more likely to feel drained (adjusted odds ratio = 2.2–5.8, P < 0.0001), have poor sleep quality (adjusted odds ratio = 1.9–3.7, P < 0.0001), and have QoL mental and physical composite scores 2.3–6.7 points lower (P < 0.0001) than patients with no/mild pruritus. Pruritus in patients undergoing HD was associated with a 23% higher mortality risk (P = 0.09). The many poor outcomes associated with pruritus underscore the need for better therapeutic agents to provide relief for the 40–50% of prevalent patients undergoing HD substantially affected by pruritus. Pruritus in new patients with end‐stage renal disease likely results from uremia or pre‐existing conditions (not HD per se), indicating the need to understand development of pruritus before end‐stage renal disease.     

Correlation study between hydrogen absorption property and lattice structure of Mg-based BCC alloys

Nanostructured Mg₆₀Ni₅Co_mX_35 − m (X = Co, B, Al, Cr, V, Pd and Cu) body centered cubic (BCC) alloys were synthesized by mechanical alloying method. These Mg-based alloys with different lattice parameters can show significantly different hydrogen absorption properties. The BCC alloys with lattice parameter in the range of 0.300∼0.308 nm absorb large amount of hydrogen at 373 K and the BCC alloys with the parameter larger than 0.313 nm have difficulty to absorb hydrogen at this temperature. Geometric effect is thought to be one of the dominant factors to affect the hydrogen absorption property of interstitial alloys. Nanostructure, fresh surface area and defects produced during mechanical alloying process are also important facts that make Mg-based alloys absorb hydrogen at 373 K.     

Characterization of deep centers in semi-insulating SiC and HgI2: Application of discharge current transient spectroscopy

In order to characterize traps in semi-insulating 4H-SiC and HgI₂ regarded as an attractive semiconductor for X-ray detectors, we apply discharge current transient spectroscopy (DCTS), which is a graphical peak analysis method based on the transient reverse current of a diode. In high-purity semi-insulating 4H-SiC whose diode may detect X-rays or γ-rays, DCTS can detect two types of trap species, and can determine those densities and emission rates. The emission rates of detected traps are close to each other, suggesting that thermally stimulated current (TSC) may not distinguish between these two types of traps. In semi-insulating HgI₂, the densities and emission rates of two types of trap species are also determined by DCTS. Therefore, it is demonstrated that DCTS is a powerful method for determining the densities and emission rates of traps in semi-insulating semiconductors     

Synthesis of Mg2FeD6 under low pressure conditions for Mg2FeH6 hydrogen storage studies

Mg₂FeD₆ is successfully synthesised with various degrees of purity using reactive ball milling and annealing under low pressure deuterium conditions to a maximum of 10 bar. The deuteride of the low cost ternary metal hydride Mg₂FeH₆, is synthesised to enable further characterisation studies such as isotopic exchange behaviour. Both on laboratory and industrial scales, keeping the pressure low reduces the need for expensive compression systems and also minimises the quantity of gas necessary for use; therefore it is important to assess synthesis under these cost effective conditions. This is especially the case when using a specialised gas such as high purity deuterium. The maximum pressure chosen is 10 bar, to comply with the High Pressure Safety Act in Japan. This Safety Act limits the use of any gas including hydrogen and deuterium to 10 bar eliminating the use of traditional synthesis methods for Mg₂FeH₆ or Mg₂FeD₆ synthesis at high pressure (120 bar). Ball milling parameters such as milling times, ball to powder ratios as well as sintering times were altered to achieve improved Mg₂FeD₆ yields under these low pressure conditions.     

Investigation of Wall Shear Stress in Cardiovascular Research and in Clinical Practice—From Bench to Bedside

In the 1900s, researchers established animal models experimentally to induce atherosclerosis by feeding them with a cholesterol-rich diet. It is now accepted that high circulating cholesterol is one of the main causes of atherosclerosis; however, plaque localization cannot be explained solely by hyperlipidemia. A tremendous amount of studies has demonstrated that hemodynamic forces modify endothelial athero-susceptibility phenotypes. Endothelial cells possess mechanosensors on the apical surface to detect a blood stream-induced force on the vessel wall, known as “wall shear stress (WSS)”, and induce cellular and molecular responses. Investigations to elucidate the mechanisms of this process are on-going: on the one hand, hemodynamics in complex vessel systems have been described in detail, owing to the recent progress in imaging and computational techniques. On the other hand, investigations using unique in vitro chamber systems with various flow applications have enhanced the understanding of WSS-induced changes in endothelial cell function and the involvement of the glycocalyx, the apical surface layer of endothelial cells, in this process. In the clinical setting, attempts have been made to measure WSS and/or glycocalyx degradation non-invasively, for the purpose of their diagnostic utilization. An increasing body of evidence shows that WSS, as well as serum glycocalyx components, can serve as a predicting factor for atherosclerosis development and, most importantly, for the rupture of plaques in patients with high risk of coronary heart disease.     

Label-free electrochemical immunoassay for the detection of human chorionic gonadotropin hormone

Here we report on a new and rapid immunoassay for the label-free voltammetric detection of human chorionic gonadotropin hormone (hCG) in urine. Monitoring the changes in the current signals of antibodies (Abs) before and after the binding of the antigen (Ag) provides the basis for an immunoassay that is simple, rapid, and cost-effective. Since hCG is found at highly elevated levels in pregnant female urine with the range of 30,000-200,000 mIU/mL (approximately 30-200 nM) by 8-10 weeks into pregnancy, its label-free electrochemical detection was achieved by using our method. The coverage of the electrode surface with the Ab and the incubation time with the target Ag were optimized for the detection of hCG. The limit of detection of our method was calculated to be 15 pM (n = 3, approximately 15 mIU/mL) in synthetic hCG samples and 20 pM (n = 3, approximately 20 mIU/mL) in human urine. The electrochemical results for the detection of hCG in the urine samples were in agreement with the results obtained using a reference system, enzyme-linked immunosorbent assay. Further research about the intrinsic electroactivity of Abs and their target molecules would surely provide new and sensitive screening assays, as well as extensive data regarding their interaction mechanisms.     

Mechanical properties of the flexible‐type epoxy/clay nanocomposites prepared by slurry method

The bisphenol‐F type flexible epoxy resin, having a good flexibility, was combined with an organo‐ and slurry‐clay. The clay dispersions in the obtained epoxy/clay systems are significantly different depending on the type of clay. Particularly, the epoxy/slurry‐clay system showed a high clay dispersibility into the epoxy matrix and was transparent in spite of the addition of 10 wt % clay. This result means that the swelling of the clay with formamide is effective for the expansion of the basal spacing of the clay. The slurry‐clay nanocomposite (clay content: 5 wt %) showed a 4 times higher fracture energy than the neat epoxy system in the tensile test, though the organo‐clay system (clay content: 5 wt %) was 1.5 times higher. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Sensing technique of silver nanoparticles as labels for immunoassay using liquid electrode plasma atomic emission spectrometry

We report the use of liquid electrode plasma-atomic emission spectrometry (LEP-AES) in protein sensing studies employing Ag nanoparticle labeling. LEP-AES requires no plasma gas and no high-power source and is suitable for onsite portable analysis. Human chorionic gonadotropin (hCG) was used as a model target protein, and the immunoreaction in which hCG is sandwiched between two antibodies, one of which is immobilized on the microwell and the second is labeled with Ag nanoparticles, was performed. Sensing occurs at the narrow pass in the center of a quartz chip following oxidative dissolution of the Ag nanoparticles by nitric acid. hCG was analyzed in the range from 10 pg/mL to 1 ng/mL, and the detection limit for hCG was estimated at 1.3 pg/mL (22.8 fM). The proposed detection method has a wide variety of promising applications in metal-nanoparticle-labeled biomolecule detection.     

Ultra-long-haul 40-Gbit/s-based DWDM transmission using optically prefiltered CS-RZ signals

Ultra-long-haul 42.7-Gbit/s-based dense wavelength-division multiplexing (DWDM) transmission using optically prefiltered carrier-suppressed return-to-zero (CS-RZ) signal has been experimentally investigated. First, we have numerically and experimentally evaluated the impact of 3-dB bandwidth and filter detuning of bandlimiting filters on the 42.7-Gbit/s CS-RZ signal in back-to-back condition. We found that the asymmetrically filtered CS-RZ signal had a great potential for ultra-DWDM applications. Next, we have numerically and experimentally investigated the basic transmission characteristics of a 45-GHz-wide prefiltered CS-RZ signal, such as the robustness against residual dispersion, nonlinear effects, and PMD, and have confirmed that the prefiltered CS-RZ signal had less tolerance against fiber nonlinearity than an unfiltered CS-RZ signal. Finally, we have experimentally investigated the optimum filtering condition for 65- or 45-GHz-wide prefiltered CS-RZ signals in the ultra-long-haul DWDM transmission and have conducted the 70- and 50-GHz spaced 32 /spl times/ 42.7Gbit/s transmission using prefiltered CS-RZ signals. Through these experiments, we have confirmed the effectiveness of prefiltered CS-RZ signal ultra-long-haul DWDM transmission.     

Characteristics of information diffusion in blogs, in relation to information source type

A novel method is presented to analyze the dynamics of social media, i.e., information diffusion properties, for information recommendation and ranking. In social media such as blogs, various information diffuses over time. As a result, a network structure is constructed. In an information diffusion network, each influential information source has an affected subnetwork whose nodes are reachable from it. We define three information diffusion properties of the subnetwork using the numbers of three types of directed two-edge connected subgraphs, which are basic structures in a directed acyclic graph such as an information diffusion network. Each basic structure type is related to information scattering, information gathering, or information transmission. We visualized and analyzed the structure of information diffusion networks extracted for various topics. Furthermore, we characterized the information diffusion properties by using the rank correlation coefficient, precision, and mean reciprocal rank and mean average precision of three types of information sources: official sites, news articles, and consumer generated media pages. We found that the three information diffusion properties have different characteristics and give priority to different types of information sources.