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Biomedical subjects

K Iijima

Publications and source records attributed to K Iijima.

At least 289 records · Page 16Linked to original sources
PubMed1984

Lack of cross-reactivity between human placental and rat liver glucocerebrosidases.

The production of anti-human placental glucocerebrosidase antibodies in rabbits immunized with a mixture of human placental glucocerebrosidase and Freund's complete adjuvant was confirmed by the immunoprecipitation reaction, immunocompetition and Graber and Williams' immunoelectrophoresis. These immunochemical techniques also unviled a lack of cross-reactivity between human placental and rat liver glucocerebrosidases against the rabbit antiserum.

Animals↗
PubMed1984

Proliferative kinetics and chromosome damage in trisomy 21 lymphocyte cultures exposed to gamma-rays and bleomycin.

Lymphocytes from patients with Down's syndrome (trisomy 21) have been investigated for cell cycle kinetics, cell proliferation delays, and chromosomal aberrations after exposure to gamma-rays or bleomycin. Analysis by sister chromatid differential staining revealed that trisomy 21 lymphocytes started cell cycling about 5 hr earlier than did normal diploid lymphocytes after phytohemagglutinin stimulation as a whole, but that cycling trisomic and normal cells had the same mean cell cycle times. When exposed to gamma-rays or bleomycin in G0, trisomy 21 lymphocytes showed a 30% or, on average, 50% longer duration of cell turnover times, respectively, than normal cells; only bleomycin-treated trisomic cells had a biphasic dose-response. Frequencies of dicentrics and rings in first-division cells after gamma-ray or bleomycin exposure were twice as high in trisomic cells as in normal cells. The frequency of aberrations decreased by 50% (gamma-ray-exposed) or 65 to 85% (bleomycin-treated) through successive divisions; trisomic cells showed a more marked decline in aberration yields compared to normal cells after bleomycin treatment. These data support the idea that circulating lymphocytes in trisomy 21 patients have a shorter average life span or a younger average age.

Bleomycin↗
PubMed1984

[Experimental model producing global brain ischemia by clamping the aorta in dogs].

Canine cerebral blood flow is supplied not only through carotid and vertebral arteries, but also through rich network of collaterals. Therefore, it is said that total body arrest is requested to assure the global brain ischemia. The global ischemic models, reported previously, were by the simultaneous occlusion of aorta and vena cava. In our model, however, the global cerebral ischemia was produced by clamping only the ascending aorta. Cardiovascular changes such as increases in left ventricular and pulmonary arterial pressure, and decrease in left ventricular dp/dt followed after ceasing of ascending aortic blood stream. The heart continued to beat during 60 minutes of the clamping. Despite of increased central venous pressure, sagittal sinus pressure and intracranial pressure remained unchanged during the aorta clamping. Ten-minutes of total cerebral ischemia was produced in 46 dogs and successful studies on cerebral and systemic variables were carried out in 68% of them. The method of clamping the aorta without occlusion of vena cava seems to be unsuitable for long term survival study because of severe loading of lung circulation. However, we conclude that this simple model is of great use for short term experiment on global brain ischemia.

Animals↗
PubMed1983

Histochemical studies on the distribution of thiamine pyrophosphatase and enzymes related to carbohydrate metabolism in the intercalated neurons of the rat supraoptic nucleus.

Histochemical studies have been conducted by applying hexokinase (HK), aldolase (AD), glyceraldehyde-3-phosphate dehydrogenase (G3), succinate dehydrogenase (SDH), glucose-6-phosphate dehydrogenase (G6PD), and thiamine pyrophosphatase (TPPase) methods, as well as Nissl staining and Gomori's chrome-alum-hematoxylin-phloxine (CHP) methods to intercalated neurons of the supraoptic nucleus (SO) on Wistar strain rats. Intercalated neurons reacted weakly to the AD, G3, G6PD, and SDH tests, indicating that they belong to the category of ordinary neurons with low carbohydrate metabolism. Many fibrous astrocytes showing strong HK reactions surround neurosecretory neurons. However, they do not surround intercalated neurons with mild HK activity. These results indicate that the latter receive a poor supply of energy from glucose in the circulating blood in contrast to the former. Intercalated neurons are very rich in Nissl substance but lack CHP-positive material. They may have a high potential for synthesizing protein. The principal morphological features of the TPPase-positive Golgi material are peculiar and heterogeneous shape and poor development. These findings together with mild G6PD activity suggest that intercalated neurons are very likely to have poor synthesizing activity.

Animals↗
PubMed1983

Influence of calcium concentration in the medium on the cell proliferation and glycosaminoglycan synthesis of human diploid skin fibroblasts in culture.

Changes of the glycosaminoglycan (GAGs) fractions in the medium, the cell surface of human diploid skin fibroblasts and the relation between GAGs synthesis and cell growth in cultured media containing various Ca++ concentrations were investigated by means of electrophoretic fractionation. The results demonstrated that the synthesis of the hyaluronic acid (HA) fraction was increased with increase of the Ca++ concentration in the medium, and this change appeared to be linked to the condition of cell growth. The synthesis of the heparan sulfate and dermatan sulfate (HS + DS) fraction was decreased with increase of the Ca++ concentration in the medium, and this change depended largely on the Ca++ concentration in the medium rather than the cell growth. The synthesis of the chondroitin sulfate (Ch-s) fraction was also decreased with increase of the Ca++ concentration in the medium. However, this change was neither controlled especially by the Ca++ concentration in the medium nor by the condition of cell growth, but reflected the decrease of total GAGs synthesis by the increase of the Ca++ concentration in the medium.

Calcium↗
PubMed1983

Collagenase activity in human saliva.

Fairly high collagenase activity was initially demonstrated in human whole saliva, and the activity from patients with periodontal diseases was statistically higher than that from healthy subjects. Based on some characteristic properties, the collagenase in whole saliva appeared to be of tissue, rather than bacterial, origin.

Adolescent↗
PubMed1982

Histochemical studies on the relationship between the morphology of the Golgi apparatus and G6PD activity in the locus coeruleus and dorsal vagal nucleus of the rat (application of karyometry).

Histochemical studies on the distribution of TPPase and G6PD in the neurons of locus coeruleus (LC) and dorsal vagal nucleus (DVN) of rats have been conducted by using the TPPase method, the G6PD method, karyometry, and statistics under normal conditions. 1. Neurons of the LC and DVN may undergo phasic changes of the GOLGI apparatus (GA) under normal condition. 2. No significant difference was found between neurons of the LC and DVN in regard to the GA morphology, but in general the latter revealed more complicated and developed GA than in the former. 3. Surprisingly, the G6PD activity of LC neurons was very weak. This is in agreement with the previous report by IIJIMA and IMAI (1975), and in disagreement with FRIEDE (1966). 4. An intimate parallel relationship was found between the GA morphology and G6PD activity in the DVN. The findings support the vigorous synthesizing activity found in the previous study of the rat supraoptic nucleus (IIJIMA 1979). In contrast to the DVN, such a parallel relationship between the Ga shape and G6PD activity was absent in the LC. Both findings strongly suggest that the role of the GA may be functionally different in the LC and DVN.

Animals↗