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We retrospectively analyzed the reproductive variables and the spontaneous malformations in the historical control data from the embryo-fetal development studies conducted in our laboratories with Kbl: JW rabbits over two decades (1990-2010) and fetal malformations induced by thalidomide in 1988, 1995 and 2007. These analyses in the control animals revealed that the reproductive variables in dams, total frequencies and profile of external, visceral and skeletal abnormalities and/or variations in the fetuses were stable over two decades. In addition, the characteristics of the malformations induced by thalidomide were reproducible at the three time points. Therefore, it is concluded that Kbl: JW rabbit is one of the useful rabbit strains to evaluate the effects of test substances on embryo-fetal development, especially in view of the chronological stability of spontaneous or drug-induced malformations in the fetuses. [ABSTRACT FROM AUTHOR]

Abstract: The mechanism of the dissociative excitation reaction of BrCN with the microwave discharge flow of Ar was investigated based on the CN(B2Σ+–X2Σ+) emission-spectroscopic and the electrostatic-probe measurements. By passing Ar and BrCN through P2O5, the contamination of H2O molecules into the reaction region was reduced to ≈30%, being confirmed by monitoring the reduction of the OH(A2Σ+–X2Π) emission intensity. The variation of the CN(B2Σ+–X2Σ+) emission intensity on the pressure of Ar, P Ar, of 0.1–0.3Torr was compared with that of the density of electrons whose kinetic energy was lower than the ionization energy of BrCN, 11.9eV. The dissociation of BrCN was found to proceed predominantly via the charge transfer from Ar+ followed by the BrCN+ −e− recombination. When the contamination of H2O molecules in the reaction region was not reduced, the dissociation via the energy transfer from metastable Ar atoms became significant. The present study shows that the contamination of H2O molecules in the reaction system makes significant effect onto the gas-phase plasma process. [Copyright &y& Elsevier]

Abstract: CN(X2Σ+) radicals were produced by the decomposition of BrCN with the microwave discharge flow of Ar under the conditions of Ar pressure in the range of 0.40–0.70Torr. The laser-induced fluorescence (LIF) spectra of the CN(A2Π i –X2Σ+), 4–0, 5–1, and 7–2 bands were observed, and their intensities were calibrated against Rayleigh-scattering intensity by Ar atoms, from which the CN(X2Σ+) radical density (n CN(X)) was determined as (0.67±0.25)×1018 to (4.42±0.83)×1018 m−3. Hydrogenated amorphous carbon nitride (a-CN x :H) films were formed by depositing the CN(X2Σ+) radicals on Si substrates in the same reaction system as LIF. The sticking probability (s) of the CN(X2Σ+) radicals onto the a-CN x :H films was determined by using n CN(X), the flow speed, and the weight () of a-CN x :H. The s value was determined as (6.4±6.4)×10−2 to (2.5±1.2)×10−2, where the errors are predominantly determined by those in n CN(X) and . The procedure described in the present study will provide a methodology to determine the sticking probability of the precursor radicals of the film formation based on the gas-phase LIF spectroscopy. [Copyright &y& Elsevier]

Rabbits are valuable experimental animals used to evaluate the teratogenicity of chemical entities. If teratogenicity is recognized, it is very important to investigate the pathogenesis to assess the potential risk in humans. For this investigation, whole-mount in situ hybridization (WISH) is highly useful for visualizing spatial and temporal changes in the expression patterns of the targeted genes and or proteins. In this chapter, the WISH method in rabbit embryos, using a digoxigenin-labeled RNA probe, and the morphometric analysis of the expression pattern is described.