Prenatal interphase FISH diagnosis of PLP1 duplication associated with Pelizaeus–Merzbacher disease

A submicroscopic genomic duplication in Xq22.2 that contains the entire proteolipid protein 1 gene (PLP1) is responsible for the majority of Pelizaeus–Merzbacher disease (PMD) patients. We previously developed an interphase FISH assay to screen for PLP1 duplications in PMD patients using peripheral blood and lymphoblastoid cell lines. This assay has been utilized as a clinical diagnostic test in our cytogenetics laboratory. To expand usage of the interphase FISH assay to prenatal diagnosis of PLP1 duplications, we examined three PMD families with PLP1 duplications utilizing aminiotic fluid samples. In two families the FISH assay revealed fetuses with PLP1 duplications, whereas the other fetus showed a normal copy number of PLP1. Haplotype analyses, as well as an additional FISH analysis using postnatal blood samples, confirmed the results of the prenatal analyses. Our study demonstrates utility of the interphase FISH assay in the prenatal diagnosis of PLP1 duplications in PMD. Copyright © 2001 John Wiley & Sons, Ltd.     

Decomposition of 2,2',4,4',5,5'-hexachlorobiphenyl with iron supported on an activated carbon from an ion-exchange resin

An activated carbon (AC) containing a high concentration (374 mg g⁻¹) of Fe was prepared by carbonization of an ion-exchange resin. To examine its chemical reactivity as a catalyst to decompose 2,2′,4,4′,5,5′-hexachlorobiphenyl (PCB-153), the decomposition parameters of temperature and time were varied under air or N₂. Decomposition at 350 °C was achieved within 15 min under air and 30 min under N₂, and the efficiency of PCB-153 decomposition was 99.7% and 98.0%, respectively. An analysis of inorganic chloride ions revealed that PCB-153 was mineralized effectively during the decomposition. The Brunauer-Emmett-Teller (BET) surface area and pore volume of the AC were measured to assess the adsorption capacity before and after the decomposition. The differences between decomposition under air and N₂ reflected the differences in the BET surface and pore volume measurements. A decomposition pathway was postulated, and the reactive characteristics of chlorine atoms loaded on the benzene rings followed the order of para > meta > ortho, which agrees with the calculated results from a density functional theory study.     

When fragmented coral spawn? Effect of size and timing on survivorship and fecundity of fragmentation in <Emphasis Type="Italic">Acropora formosa</Emphasis>

In order to determine competency of sexual reproduction and survival rate after fragmentation, the branching coral Acropora formosa was fragmented and fragments in three different sizes (ca. 5, 10 and 20 cm long) and three different stages of gametogenesis were transplanted on coral pavement. Their oocyte development and fecundity, as well as spawning were monitored for a 3-year period. The oocyte development was affected by both fragment size and by the developmental stage of oocytes when fragmented. In small fragments, the oocytes were resorbed while in large fragments they continued development. Oocytes in the early vitellogenic stage at the time of fragmentation were resorbed, whereas those in the late stage continued developing. Smaller fragments showed a lower survival rate and histological observations of their gonads revealed resorption of oocytes, suggesting that there was a trade-off of energy between reproduction and survival. Transplanted fragments often spawned one month earlier than the donor colonies in the first year, but spawning occurred in the same month as the donors or did not occur at all in the second year and none spawned in the third year. The risk of colony death may cause the fragments to re-allocate energy for sexual reproduction.     

An axisymmetric diffusion experiment for the determination of diffusion and sorption coefficients of rock samples

Diffusion anisotropy is a critical property in predicting migration of substances in sedimentary formations with very low permeability. The diffusion anisotropy of sedimentary rocks has been evaluated mainly from laboratory diffusion experiments, in which the directional diffusivities are separately estimated by through-diffusion experiments using different rock samples, or concurrently by in-diffusion experiments in which only the tracer profile in a rock block is measured. To estimate the diffusion anisotropy from a single rock sample, this study proposes an axisymmetric diffusion test, in which tracer diffuses between a cylindrical rock sample and a surrounding solution reservoir. The tracer diffusion between the sample and reservoir can be monitored from the reservoir tracer concentrations, and the tracer profile could also be obtained after dismantling the sample. Semi-analytical solutions are derived for tracer concentrations in both the reservoir and sample, accounting for an anisotropic diffusion tensor of rank two as well as the dilution effects from sampling and replacement of reservoir solution. The transient and steady-state analyses were examined experimentally and numerically for different experimental configurations, but without the need for tracer profiling. These experimental configurations are tested for in- and out-diffusion experiments using Koetoi and Wakkanai mudstones and Shirahama sandstone, and are scrutinized by a numerical approach to identify favorable conditions for parameter estimation. The analysis reveals the difficulty in estimating diffusion anisotropy; test configurations are proposed for enhanced identifiability of diffusion anisotropy. Moreover, it is demonstrated that the axisymmetric diffusion test is efficient in obtaining the sorption parameter from both steady-state and transient data, and in determining the effective diffusion coefficient if isotropic diffusion is assumed. Moreover, measuring reservoir concentrations in an axisymmetric diffusion experiment coupled with tracer profiling may be a promising approach to estimate of diffusion anisotropy of sedimentary rocks.     

Determination of adrenal steroids by microfluidic chip using micellar electrokinetic chromatography

This paper describes a sensitive and convenient method to separate progesterone, 17alpha-hydroxy progesterone, cortexolone, hydrocortisone and cortisone, all of which are steroids and have similar structures, using microfluidic chip-based technology with UV detection at 252 nm. We successfully obtained high-speed separation of the five steroids within 70 s in optimized microfluidic controls and micellar electrokinetic chromatography (MEKC) separation conditions. Fairly good linearity with correlation coefficient of over 0.98 from 10 or 20 to 100 mg/l steroid chemicals was obtained. The limits of detection obtained at a signal to noise ratio of 3 were from 3.89 to 7.80 mg/l. The values of the relative standard deviation (RSD) were 0.98-1.34% for repetitive injection (n = 12) and the intraday and interday RSDs were below 6%. The highly stable response reflected the feasibility of this method.     

Model of turbulence penetration into a suspension layer on a sediment bed and effect on vertical solute transfer

The vertical diffusional mass (solute) transfer through a suspended sediment layer, e.g. at the bottom of a lake, reservoir or estuary, by the propagation of velocity fluctuations from above was investigated. The attenuation of the velocity fluctuations in the suspension layer and the associated effect on solute transfer through the suspension layer was simulated. To represent large eddies traveling downstream in water over a high-concentration suspended sediment layer, a streamwise velocity fluctuation moving in downstream direction was imposed along the upper boundary of the suspension layer. Velocity fluctuations and downstream velocity were normalized by the shearvelocity (U_*) at the top of the suspension layer. Streamwise and vertical velocity components inside the suspension layer, were obtained from the 2-D continuity and the Navier–Stokes equations. The persistence of turbulence with depth—as it penetrates from the overlying water into the suspension layer—was found to depend on its amplitude, its period, and on the apparent viscosity of the suspension. The turbulence was found to propagate efficiently into the suspension layer when its frequency is low, and the apparent viscosity of the suspension is high. Effects on vertical mass transfer were parameterized by penetration depth and effective diffusion coefficient, and related to apparent viscosity of the suspension, Schmidt number and shear velocity on top of the suspension layer. The enhancement of turbulence penetration by viscosity is similar to the flow near an oscillating flat plate (Stokes’ second problem), but is opposite to turbulence penetration into a stationary porous and permeable sediment bed. The information is applicable to water quality modeling mear the sediment/water interface of lakes, river impoundments and estuaries.     

Verification of the mutually complementary effect of fly ash and clinker aggregate on the strength,heat of hydration,and alkali-silica reaction

Journal of Material Cycles and Waste Management - Although fly ash, as used for supplementary cementitious material in Portland cement concrete, can reduce the heat of hydration and suppress the...     

Modelling 3H and 14C transfer to farm animals and their products under steady state conditions

The radionuclides (14)C and (3)H may both be released from nuclear facilities. These radionuclides are unusual, in that they are isotopes of macro-elements which form the basis of animal tissues, feed and, in the case of (3)H, water. There are few published values describing the transfer of (3)H and (14)C from feed to animal derived food products under steady state conditions. Approaches are described which enable the prediction of (14)C and (3)H transfer parameter values from readily available information on the stable H or C concentration of animal feeds, tissues and milk, water turnover rates, and feed intakes and digestibilities. We recommend that the concentration ratio between feed and animal product activity concentrations be used as it is less variable than the transfer coefficient (ratio between radionuclide activity concentration in animal milk or tissue to the daily intake of a radionuclide).