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K Sekikawa

Publications and source records attributed to K Sekikawa.

85 records · Page 5Linked to original sources
PubMed1975

Analysis of multiple viral genome fragments in adenovirus 7-transformed hamster cells.

The presence of multiple copies of a portion of the viral genome was demonstrated in Ad7-transformed cells by a new method based on the kinetic analysis of labeled viral DNA reassociation in the presence of unlabeled transformed cell DNA. DNA-DNA homology measurement utilizing defined DNA fragments (restriction endonuclease digests) as labeled probes supported the above conclusion.

Adenoviridae↗
PubMed1975

Method for determination of nucleotide sequence homology between viral genomes by DNA reassociation kinetics.

A model and appropriate equations were derived for the quantitative estimation of nucleotide sequence homology between two partially related viral genomes by measurement of the initial rate of reassociation of one labeled DNA in the presence of a second unlabeled DNA. The validity and usefulness of this procedure were demonstrated by the analysis of the reassociation kinetics of labeled adenovirus 7 DNA in the presence of unlabeled adenovirus 2 DNA. Based on DNA reassociation, the extent of homology between adenovirus 2 and 7 genomes was found to be 10 to 12%. The duplex formed between adenovirus 2 and 7 DNA had the appropriate thermal stability for a well-matched DNA-DNA hybrid.

Adenoviridae↗
PubMed1972

Virus-specific ribonucleic acid in the nucleus and cytoplasm of rat embryo cells transformed by adenovirus type 2.

Nuclei were isolated from rat embryo cells transformed by adenovirus type 2. Nuclear and cytoplasmic virus-specific ribonucleic acids (RNA) were characterized and quantitated by deoxyribonucleic acid (DNA)-RNA hybrid formation with adenovirus DNA. The results indicate that most, if not all, virus-specific RNA molecules are synthesized in the cell nucleus and subsequently transported into cytoplasm where they degrade with a half-life of 1 to 2 hr. No difference in base sequences between nuclear and cytoplasmic virus-specific RNA species can be detected by hybridization competition experiment with viral DNA.

Adenoviridae↗
PubMedDate not supplied

Do the kinetics of peripheral muscle oxygenation reflect systemic oxygen intake?

To examine whether the kinetics of local muscle oxygenation reflect systemic oxygen intake, we measured the kinetics of local muscle oxygenation and systemic oxygen consumption (VO2). This study included 16 healthy males who performed an exercise tolerance test on a bicycle ergometer. During the exercise test, expiratory gas analysis was performed with an expiratory gas analyzer, and the kinetics of vastus lateralis muscle oxygenation were determined by near-infrared spectroscopy (NIRS). Oxygenated hemoglobin (OxyHb) and tissue blood oxygen saturation (StO2) gradually decreased during the exercise test, while deoxygenated hemoglobin (DeoxyHb) gradually increased. We examined correlations between the mean values of these parameters, which were calculated by time-integrating the values obtained using NIRS and dividing them by the integral time, and VO2. There was a marked positive correlation between DeoxyHb and VO2 (r = 0.893-0.986), and a marked negative correlation between StO2 and VO2 (r = 0.859-0.995). There was a negative correlation between VO2 and OxyHb (r = 0.726-0.978), and no correlation between TotalHb and VO2. These results suggest that the kinetics of peripheral muscle oxygenation reflect systemic VO2.

Adult↗