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Biomedical subjects

T Fujino

Publications and source records attributed to T Fujino.

At least 397 records · Page 22Linked to original sources
PubMed1978

The effect of norharman on the metabolism of benzo[alpha]pyrene by rat-liver microsomes in vitro in relation to its enhancement of the mutagenicity of benzo[alpha]pyrene.

The effect of norharman on the metabolism of benzo[alpha]pyrene by rat-liver microsomes was studied. Separation of the metabolites into hydrophilic and hydrophobic fractions showed that norharman inhibited the conversion of hydrophobic metabolites to hydrophilic ones. Analysis of the hydrophobic metabolites by high-pressure liquid chromatography showed that norharman also inhibited the disappearance of benzo[alpha]pyrene itself. However, large amounts of hydrophobic metabolites, such as phenol, quinones and diols, were formed in the presence of norharman, and formation of the strong mutagen 7,8-dihydroxybenzo[alpha]pyrene was increased 10-fold by norharman. The increase in formation of this compound may be one of the chief reasons why norharman enhances the mutagenicity of benzo[alpha]pyrene on Salmonella typhimurium.

Alkaloids↗
PubMed1978

Isometric contraction and relaxation times of right and left ventricles in normal subjects and in patients with right ventricular overloading measured with bidirectional echocardiography.

With the use of bidirectional echocardiography, the isometric contraction (ICT) and relaxation times (IRT) of both ventricles were measured in 14 normal subjects (N), 6 cases with right ventricular (RV) diastolic overloading (DO), and 5 cases with RV systolic overloading (SO). The RVDO group consisted of patients with atrial septal defect of ostium secundum type who had large left-to-right shunting, and the RVSO group those with pulmonary hypertension of various origins. The mean ICT and IRT in N were 28.5 +/- 4.8 and 43.8 +/- 1.7 msec for RV, and 43.3 +/- 5.6 and 60.9 +/- 9.0 msec for left ventricle (LV), respectively. The RVDO group showed no significant change in the mean ICT and IRT of RV (29.7 +/- 4.6 and 54.3 +/- 11.8 msec, respectively), but significantly greater means of ICT and IRT of LV (58.5 +/- 9.5 and 83.6 +/- 14.1 msec, respectively. In the RVSO group, the mean ICT and IRT were 51.0 +/- 4.1 and 86.8 +/- 8.2 msec for RV, and 72.4 +/- 12.2 and 116.0 +/- 20.4 msec for LV, respectively. These values were all significantly greater than the means for both N and RVDO groups, except that the mean ICT of LV was insignificantly different between the RVDO and RVSO groups. It was noted that the intervals of LV tended to increase with the increasing intervals of RV, suggesting the changes in LV function secondarily due to RV overloading. It was concluded that the measurement of ICT and IRT of both ventricles is of clinical value for evaluation of overall cardiac function in the patients with RV overloading.

Adolescent↗
PubMed1978

Electrophysiological comparison between the longitudinal and circular muscles of the rat uterus during the estrous cycle and pregnancy.

The membrane activities of the longitudinal and circular muscles bundle of rat uteri were recorded with a single sucrose gap method, using animals at various stages of the estrous cycle, pregnancy and after ovariectomy. In the longitudinal muscle during estrus, an initial plateau potential was followed by a slow potential. During diestrus and metestrus, an asynchronized action potential composed of plateau and a slow potential were exhibited. The action potential recorded in uteri taken out of an ovariectomized animal or during early pregnancy was similar to that of uteri during diestrus and metestrus. The circular muscle during estrus gave a plateau potential similar to that of the longitudinal muscle. During diestrus, metestrus, early pregnancy and in the ovariectomized uterus, the membrane activity of the circular muscle was decomposed to produced small plateaus. The spike activity took place in the longitudinal muscle after mid-pregnancy. The slow potential was dominant in the circular muscle during mid-pregnancy, while spikes were progressively generated toward term. Those differences of membrane activity between the longitudinal and circular muscle bundles were discussed in relation to the endogenous change in the sex steroid hormones.

Action Potentials↗
PubMed1978

A method of tomographic imaging using a multiple pinhole-coded aperture.

High energy collimators in use today are limited with respect to resolution and efficiency. The multiple pinhole coded aperture (hereafter abbreviated as MPCA) is a method being considered to improve the above. In our study we conducted basic experiments with an MPCA using an Anger-type gamma-camera. Using this method, we were able to perform radioisotope imaging and radioisotope tomographic effect. We have studied the resolution, detection efficiency, and tomographic effects of the MPCA. We found that, in the MPCA, detection efficiency is proportional to the number of pinholes and resolution is dependent upon the pinhole diameter. This tomographic effect is of the same principle as the stretching-type tomography, images on both side of the desired image appearing as noise images, affecting the depth resolution. Using an MPCA with a pinhole diameter of 3 mm and 3 pinholes positioned in an equilateral triangular pattern measuring 7.8 cm on each side, we attained a depth resolution of 3 cm. Because the MPCA method involves complicated image processing, the resulting image contains a factor of 2n-2 (where n is the number of pinhole) of noise, affecting the depth resolution.

Radionuclide Imaging↗