Important role of blood rheology in atherosclerosis of patients with hemodialysis

Concerning a role of blood rheology for atherosclerosis in patients with hemodialysis (HD), little data are available. It may be due to the fact that the method for evaluating rheologic properties of circulating blood has been limited. We examined blood rheology in 118 HD patients by using microchannel array flow analyzer that makes it possible to directly observe the flow of blood cell elements through the microchannel. Transit time (T(B)) of heparinized whole blood through slit pores (7 x 30 microm) was used as an index of rheology and related with various inflammatory biomarkers such as high-sensitive CRP (hsCRP), monocyte chemotactic protein-1, osteopontin, or fibrinogen (Fg). Moreover, as a surrogate marker of atherosclerosis, carotid intima-media thickness (IMT) and aortic stiffness evaluated by brachial-ankle pulse-wave velocity (baPWV) were studied. In HD patients, T(B) had strong positive correlations with hsCRP (r = 0.427; p < 0.00001), Fg (r = 0.452; p < 0.00001), and osteopontin (r = 0.227; p < 0.0134). Further, T(B) was significantly well correlated with IMT (r = 0.400; p < 0.0001) and PWV (r = 0.470; p < 0.0001). Multivariate regression analysis showed that baPWV, IMT, Fg, hematocrit, white blood cell count, and CRP were chosen as significant explanatory factors for T(B.) These results suggest that blood rheology may play an important role for atherosclerosis in patients with HD.     

Effects of Jitter and Cycle Slipping of Phase Reference Upon Unique Word Missed Detection in QPSK Systems

The effects of phase jitter and cycle slipping of the recovered carrier upon unique word (UW) missed detection in QPSK systems are investigated. Schrempp et al. have already presented the relationship between the UW missed detection probability (UWMP) and the bit error probability, which is simple and useful as long as the phase reference is noiseless. However, when the authors recently made some theoretical and experimental assessments of UW missed detection, they found that the above disturbances of the recovered carrier significantly affected the UW missed detection performance. Specifically, the actual UWMP was often worse than that predicted hy Schrempp et al. In fact, a bottoming effect takes place in the UWMP versus UW length characteristic. In this paper, after obtaining the conditional symbol and bit error probabilities for the recovered carrier with some phase error, we discuss the nature of phase fluctuation and cycle slipping for the recovered carrier. Consequently, we derive general expressions for the UWMP in both CPSK and DCPSK transmissions. The UWMP's are numerically calculated, and are then compared to our experimental data.     

Possibility of Thermal Protection in Earth Re-entry Flight by MHD Flow Control with Air-Core Circular Magnet

The possibility of thermal protection in an earth re-entry flight by the magnetohydrodynamic (MHD) flow control with an air-core circular magnet producing about 1 T or less on the wall surface of a space vehicle is examined by r-z two-dimensional numerical simulations. The present study adopts a hemisphere with a radius of 1.0 m as the nose shape of a space vehicle. The numerical results show that aerodynamic heating can be reduced by the MHD flow control with an air-core circular magnet, and also that the maximum wall heat flux and the effect of the MHD flow control become prominent with the magnitude of coil current and the flight altitude. Furthermore, it is found that there is an optimum magnet size to maximize the effect of MHD flow control under constant exciting magnetic energy, and also the optimum size gets reduced with the decrease in the flight altitude. © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Reconstruction of cartilage tissue using scaffold-free organoid culture technique

We applied the scaffold-free culture method to chondrocytes and attempted to reconstitute articular cartilage grafts. Primary rat costal chondrocytes were immobilized into hollow fibers by centrifugation at a density of 3 x 10(8) cells/cm(3) to induce the formation of cylindrical-shaped multicellular aggregates (organoids) and cultured for one month. The organoids were evaluated by histological and gene expression analyses. Chondrocytes formed cylindrical organoids in hollow fibers (HFs). Histochemical analysis revealed the accumulation of a cartilage extracellular matrix (collagen and proteoglycan) around cells in the lumen of HFs with culture time, forming a low-cellular-density tissue similar to native cartilage by day 28. Furthermore, in contrast to that in traditional monolayer culture, the organoid maintained the gene expression of the cartilage extracellular matrix (type II collagen, aggrecan) for one month of culture. In conclusion, our organoid formation method was effective in producing a cartilage-like tissue. This result suggests that the technique may be applicable to the development of an articular cartilage graft.     

Exploring the Minimal RNA Substrate of Flexizymes

Flexizymes are tRNA acylation ribozymes that have been successfully used to facilitate genetic code reprogramming. They are capable of charging acid substrates onto various tRNAs and tRNA analogues. However, their minimal RNA substrate has not been investigated. Here we have designed fluorescently labeled short RNAs corresponding to the four, three, and two bases (4bRNA, 3bRNA, 2bRNA) at the tRNA 3′-end and explored the minimal RNA substrate of flexizymes, dFx and eFx. 3bRNA was the observed minimal RNA substrate of the flexizymes, but the efficiency of acylation of this short RNA was two to three times lower than that of 4bRNA. The efficiency of acylation of 4bRNA was comparable with that of the microhelix, a 22-base RNA conventionally used as a tRNA analogue for analyzing acylation efficiency. We also compared the efficiencies of acylation of the microhelix and 4bRNA with various acid substrates. Thanks to the short length of 4bRNA, its acyl-4bRNA products exhibited larger mobility shifts in gel electrophoresis than those exhibited by acyl-microhelix products with every substrate tested. This indicated that 4bRNA was an ideal RNA substrate for analyzing the efficiency of acylation by flexizymes.     

Dimeric C34 Derivatives Linked through Disulfide Bridges as New HIV-1 Fusion Inhibitors

C34, a 34-mer fragment peptide, is contained in the HIV-1 envelope protein gp41. A dimeric derivative of C34 linked through a disulfide bridge at its C terminus was synthesized and found to display potent anti-HIV activity, comparable with that of a previously reported PEGylated dimer of C34REG. The reduction in the size of the linker moiety for dimerization was thus successful, and this result might shed some light on the mechanism of the suppression of six-helix bundle formation by these C34 dimeric derivatives. Addition of a Gly-Cys(CH₂CONH₂)-Gly-Gly motif at the N-terminal position of a C34 monomeric derivative significantly increased the anti-HIV-1 activity. This moiety functions as a new pharmacophore, and this might provide a useful insight into the design of potent HIV-1 fusion inhibitors.     

Characterization of Acetylxylan Esterase from White-Rot Fungus Irpex lacteus

The carbohydrate esterase family 1 (CE1) in CAZy contains acetylxylan esterases (AXEs) and feruloyl esterases (FAEs). Here we cloned a gene coding for an AXE belonging to CE1 from Irpex lacteus (IlAXE1). IlAXE1 was heterologously expressed in Pichia pastoris, and the recombinant enzyme was purified and characterized. IlAXE1 hydrolyzed p-nitrophenyl acetate, α-naphthyl acetate and 4-methylumbelliferyl acetate, however, it did not show any activity on ethyl ferulate and methyl p-coumarate. We also examined the activity on partially acetylated and feruloylated xylan extracted from corncob by hydrothermal reaction. Similarly, ferulic and p-coumaric acids were not liberated, and acetic acid was only detected in the reaction mixture. The results indicated that IlAXE1 is an acetylxylan esterase actually reacted to acetyl xylan. However, since IlAXE1 was unable to completely release acetic acid esterifying xylopyranosyl residues, it is assumed that acetyl groups exhibiting resistance to deacetylation by IlAXE1 are present in corn cob xylan.     

Study of the properties of nickel oxide and nickel as precursors for the tartaric acid-NaBr-modified nickel catalyst

Nickel oxide was prepared by the decomposition of nickel hydroxide and then the nickel oxide was reduced to form the nickel catalyst. The properties of the nickel oxide and the reduced nickel were studied in relation to the enantio-differentiating ability (e.d.a.) of a tartaric acid-NaBr-modified reduced nickel catalyst. The modified nickel catalyst prepared from nickel oxide with less non-stoichiometric oxygen produced a high e.d.a. for the hydrogenation of methyl acetoacetate. The high crystallinity of the nickel oxide and the resultant nickel would be required to attain a high e.d.a.     

Disparities of indoor temperature in winter: A cross-sectional analysis of the Nationwide Smart Wellness Housing Survey in Japan

The WHO Housing and health guidelines recommend a minimum indoor temperature of 18°C to prevent cold-related diseases. In Japan, indoor temperatures appear lower than in Euro-American countries because of low insulation standards and use of partial intermittent heating. This study investigated the actual status of indoor temperatures in Japan and the common characteristics of residents who live in cold homes. We conducted a nationwide real-world survey on indoor temperature for 2 weeks in winter. Cross-sectional analyses involving 2190 houses showed that average living room, changing room, and bedroom temperatures were 16.8°C, 13.0°C, and 12.8°C, respectively. Comparison of average living room temperature between prefectures revealed a maximum difference of 6.7°C (Hokkaido: 19.8°C, Kagawa: 13.1°C). Compared to the high-income group, the odds ratio for living room temperature falling below 18°C was 1.38 (95% CI: 1.04-1.84) and 2.07 (95% CI: 1.28-3.33) for the middle- and low-income groups. The odds ratio was 1.96 (95% CI: 1.19-3.22) for single-person households, compared to households living with housemates. Furthermore, lower room temperature was correlated with local heating device use and a larger amount of clothes. These results will be useful in the development of prevention strategies for residents who live in cold homes.