Isolation and molecular characterization of a serotype 9 human rotavirus strain.

A human rotavirus strain, designated AU32, that belongs to serotype 9 was isolated and was compared by RNA-RNA hybridization with recently established two serotype 9 strains (WI61 and F45) as well as other prototype human strains. These three strains exhibited a very high degree of homology with one another and shared a high degree of homology with strains belonging to the Wa genogroup but not with strains belonging to either the DS-1 or AU-1 genogroup. These results suggest that genetic constellation of the serotype 9 strains is similar to that of the commonest human rotavirus despite the recent recognition of this serotype.     

Effects of Light on Chlorophyll Formation in Cultured Tobacco Cells II. Blue Light Effect on 5-Aminolevulinic Acid Formation

5-Aminolevulinic acid (ALA) accumulation in dark-grown tobaccocallus cells in the presence of levulinic acid (LA) was followedunder blue or red light or in continuous darkness. Significantformation of ALA continued in the dark. The protochlorophyll-(ide) (Pchl) content of dark-incubated cells remained low becauseof its turnover. We inferred that the feedback inhibition ofALA synthesis by Pchl would not occur in darkincubated calluscells. ALA formation was enhanced by blue light, and this effectreached saturation at an intensity of about 800 mW.m^–2.Neither weak nor strong red light affected ALA formation. Fullenhancement of ALA formation by blue light was attained afterfairly long continuous illumination of the callus cells. Thisblue lightenhanced activity of ALA synthesis declined very slowlyduring the subsequent dark incubation. The blue light enhancement of ALA formation was observed incallus cells supplied with sucrose over a wide range of concentrations.Pchl regeneration in carbon-starved callus cells, supplied withglutamate at various concentrations, was also markedly enhancedby blue light. Respiration of the callus cells was not enhancedby blue light. A possible role of blue light in regulating ALAformation in callus cells is discussed. ¹Dedicated to the late Professor Joji Ashida. (Received September 3, 1982; Accepted April 5, 1983)     

Aphidicolin resistant mutant of which DNA polymerase alpha is induced by this drug

Mutants resistant to aphidicolin, a specific inhibitor of DNA polymerase α of eukaryotic cells, were selected from cultured FM3A cells, derived from mouse mammary carcinoma. One of them, designated as Aph 212, grew in the presence of 1 μg/ml of the drug, which did not permit wild type cells to grow. The resistance of Aph 212 cells to aphidicolin seems to be due to the increment of the activity of DNA polymerase α when Aph 212 cells were cultivated in the presence of the drug.     

Nanosecond time-resolved fluorescence investigations of temperature-induced conformational changes in cytochrome oxidase in phosphatidylcholine vesicles and solubilized systems

Intrinsic and lipid phase transition-induced conformational changes in cytochrome oxidase in phosphatidylcholine vesicle and solubilized systems were examined by the fluorescence lifetime of N-(1-anilinonaphthyl-4)-maleimide conjugated with the enzyme. The time-dependent fluorescence intensity of N-(1-anilinonaphthyl-4)-maleimide attached to cytochrome oxidase was described as a triple exponential decay. Both the intrinsic and lipid phase transition-induced conformational changes were detectable in plots of the average lifetime against temperature. In most cases a peak occurred at the temperature of the conformational change. The time-dependent emission anisotropy showed that N-(1-anilinonaphthyl-4)-maleimide embedded in cytochrome oxidase in phosphatidylcholine vesicles underwent a rapid restricted wobbling within a cone. The half-angle of the cone was around 30 degrees for cytochrome oxidase in dimyristoyl phosphatidylcholine vesicles.     

Response of respiratory exchange ratio (R) to sinusoidal work load in humans

An examination was made of the response of respiratory exchange ratio (R), carbon dioxide output (VCO2) and oxygen uptake (VO2) to sinusoidal work load with periods (T) of 1-16 min in six healthy men to determine whether R response is sinusoidal. The influence of the ratio of the amplitude of VCO2 to that of VO2 and the phase lag between them on R response was also studied by computer simulation. The results and conclusions obtained are as follows: 1) With decrease in the period, the amplitudes of VO2 and VCO2 dropped exponentially, becoming least at T of 1 min (T = 1 min). In contrast, the amplitude of R was largest at T = 4 min and subsequently decreased progressively. 2) The peak amplitude of R at T = 4 min can be explained by the larger phase lag and relatively low of amplitude of VCO2 to VO2. 3) The smallest amplitude of R at T = 1 min was due not to the ratio of amplitude or phase lag, but to remarkably smaller amplitudes of VO2 and VCO2. 4) The phase lag of VO2 to sinusoidal work load was smaller than that of VCO2. Phase lag of R was considerably larger than that of VO2 or VCO2. 5) The response curve of VO2 and VCO2 is a sinusoidal curve with the same period as exercise. However, the response of R is not a real sinusoidal but a deformed biphasic curve with a high crest and low trough. The deformity is determined by the phase lag between VO2 and VCO2 response and also the ratio of amplitude of VCO2 to that of VO2.     

Determination of dioxopiperazine metabolites of quinapril in biological fluids by gas chromatography—mass spectrometry

The dioxopiperazine metabolites of quinapril in plasma and urine were extracted with hexane—dichloroethane (1:1) under acidic conditions. Following derivatization with pentafluorobenzyl bromide and purification of the desired reaction products using a column packed with silica gel, the metabolites were analysed separately by capillary column gas chromatography—electron-impact mass spectrometry with selected-ion monitoring. The limits of quantitation for the metabolites were 0.2 ng/ml in plasma and 1 ng/ml in urine. The limits of detection were 0.1 ng/ml in plasma and 0.5 ng/ml in urine, at a signal-to-noise ratio of > 3 and > 5, respectively. The proposed method is applicable to pharmacokinetic studies.