Biomedical subjects

M Okubo

Publications and source records attributed to M Okubo.

257 records · Page 15Linked to original sources

PubMedDate not supplied

Cyclooxygenase-2 expression in hepatocellular carcinoma.

BACKGROUND/AIMS: Cyclooxygenase-2 (Cox-2) is an isoform of cyclooxygenase, which is the key enzyme converting arachidonic acids to prostaglandins. It has been reported that Cox-2 is overexpressed in colon cancer, and that inhibition of this enzyme activity reduces colon cancer development in humans and animals. However, the significance of Cox-2 in human liver cancer is still unclear. To clarify significance of Cox-2 in liver cancer, we immunohistochemically examined expression of this enzyme in cancerous and non-cancerous tissues of hepatocellular carcinoma (HCC). METHODOLOGY: Twenty-nine patients with HCC were examined; 10 patients had well differentiated HCC, 10 had moderately differentiated HCC, and 9 had poorly differentiated HCC. RESULTS: Twenty-eight of 29 (97%) patients with HCC exhibited a positive staining. More intense staining of Cox-2 in cancer tissue rather than non-cancerous tissue was observed in 7 of 10 (70%) patients with well differentiated HCC, in 3 of 10 (30%) with moderately differentiated HCC, and in 3 of 9 (33%) with poorly differentiated HCC, respectively. Rate of higher expression of Cox-2 in cancer tissue rather than in non-cancerous tissue of well differentiated HCC was increased, compared to that of moderately and poorly differentiated HCC (7/10 vs. 6/19, p < 0.05). CONCLUSIONS: The results of the present study showed that Cox-2 is related to HCC whose histology is well differentiated.

Aged↗

PubMedDate not supplied

Dopamine-beta-hydroxylase activity after acute myocardial infarction.

After acute myocardial infarction, serial serum dopamine-beta-hydroxylase (DBH) activity was elevated in both high and low DBH subgroups. The observed increase in DBH activity on the first, second, and third days after acute myocardial infarction suggests an augmentation in sympathetic nervous system activity after acute myocardial infarction.

Acute Disease↗

PubMedDate not supplied

Methods of detection of lymphatics and their changes with oestrous cycle.

It is difficult to detect lymphatics, and it is extremely risky to identify a lymphatic by only one method. We are attempting accurate identification of a lymphatic by gradually narrowing the field of division by the use of four methods: (1) puncture injection of dye fluid; (2) arterial injection of silver nitrate solution and indian ink; (3) staining of semi- ultrathin sections with toluidine blue, and (4) confirmation by electron microscopy. Observation by these methods of the endometria of the human uterus and of rats in different stages of the respective oestrous cycles has revealed that the lymphatics change with the oestrous cycle. Interestingly, the changes are not only in the thickness but also in the number of lymphatics. Lymphatics have further been found not evenly distributed in organs but concentrated in certain areas.

Adult↗

PubMedDate not supplied

Abnormality of the post-proline-cleaving enzyme activity in mice with systemic lupus erythematosus-like syndrome.

Previous studies indicated the importance of hydrolytic enzymes in the pathogenesis of autoimmune diseases. In the present study, we examined the activities of such enzymes in various organs of the hybrids of the New Zealand Black and New Zealand White mouse (NZB/W mouse) as a laboratory model of human systemic lupus erythematosus. Of the 18 enzymatic activities tested, the activities of the post-proline-cleaving enzyme showed a particular behavior in the spleen of NZB/W mouse. The enzymatic activity progressively increased with age in contrast to the reverse tendency in the control. This phenomenon was not found in any organs other than the spleen. The activity of this enzyme showed a high level of correlation to that of proline-iminopeptidase in most organs tested from control animals. However, these correlations were almost completely absent in the spleen of NZB/W mice. This may suggest an important pathogenetic role for the post-proline-cleaving enzyme in immunological disturbances in this model animal.

Animals↗

PubMedDate not supplied

Experimental study of measurement of regional bone blood flow in the adult mongrel dog using radioactive microspheres.

To date, no one has conclusively accurately measured the regional bone blood flow mainly due to the lack of a proper investigative method. In this study, regional blood flow in the femur and tibia in adult mongrel dogs were studied using 85Sr-and 141Ce-labeled microspheres with a diameter of 15 +/- 5 microns. The blood flow rates were calculated by relating the radioactivity from tissue samples that from sample blood with a known flow. The highest rate of blood flow, 48.7 ml/min/100 g, was found in the femoral marrow and the lowest, 3.0 ml/min/100 g, in the diaphyseal cortex of the tibia. Flow rates in the metaphyseal regions, about 15 or 20 ml/min/100 g, were one and a half or 2 times greater than those in the epiphyseal regions. These values were mostly within the range of values reported by other investigators. Radioactive microspheres can be applied not only to physiological conditions but also to various pathological conditions if their size and the dose, the site and method of injection and tissue sampling are investigated further.

Animals↗