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Biomedical subjects

S Akizuki

Publications and source records attributed to S Akizuki.

105 records · Page 6Linked to original sources

Foamy cells in itp spleens and in granulomas induced by murine platelets, commercialized phospholipids, and erythrocyte membrane. Histological and ultrastructural studies.

A large number of foamy cells were noted in the spleens from fourteen ITP patients, and two patients who received a large amount of platelet rich plasma. Using the unlabelled immunoperoxidase method, these foamy cells were shown to contain platelet antigen. Platelets in varying stages of intracellular digestion, from intact-appearing forms to myelin-like materials, were disclosed in foamy cells. Foamy cells were experimentally induced in granulomas by subcutaneous injection of platelets with or without accompanied administration of steroid, the platelets reacted with anti-murine platelet antibody, commercialized phospholipids (PE, PC, SM, PS, and the mixture of them), and the red blood cell membrane. The foamy cells induced by the subcutaneous injection of platelets are similar to those in the spleens of ITP patients. The lipid in foamy cells is chiefly derived from the membrane phospholipid of injected platelets. Concentric myelin-like materials were also noted in the foamy cells after injection of erythrocyte membrane. The myelin-like materials in these foamy cells are similar to those appearing in macrophages following injection of PC and SM. This suggests that these phospholipids derived from cell membrane are more resistant to intracellular digestion by lysosomal enzymes. We conclude that the foamy appearance of the cordal macrophage in ITP spleens results from incomplete intracellular degradation of platelet membrane.

Adolescent↗

Comparative effects of nitroglycerin and nifedipine on myocardial blood flow and contraction during flow-limiting coronary stenosis in the dog.

Both nifedipine and nitroglycerin are used to treat angina pectoris. The comparative effects of these agents on myocardial blood flow and contraction in the setting of flow-limiting coronary stenosis are poorly understood. Thus 24 open chest dogs underwent carotid to left anterior descending coronary arterial perfusion with coronary flow probe and perfusion pressure monitoring. Segment length was measured with ultrasonic crystals in the subendocardial ischemic and nonischemic zones. Myocardial blood flow was measured with radioactive microspheres. Partial coronary occlusion was performed to attain a diastolic perfusion pressure of 40 mm Hg. Twelve dogs received intravenous nifedipine, 3 micrograms/kg per min, and 12 received intravenous nitroglycerin to reduce aortic pressure by 20 mm Hg. Partial occlusion resulted in a slight but significant decrease in segment shortening in the ischemic zone. Neither nitroglycerin nor nifedipine affected shortening in the ischemic zone. After occlusion, blood flow decreased in the subendocardial ischemic zone but was unchanged in the subepicardium. Nifedipine increased subendocardial blood flow in the nonischemic zone and decreased it in the ischemic zone but caused no change in subepicardial flow in the ischemic zone. In contrast, nitroglycerin decreased subendocardial and subepicardial blood flow in both the ischemic and nonischemic zones. In the setting of coronary stenosis, different classes of vasodilators may have varying effects on myocardial blood flow, suggesting different sites and mechanisms of action. In addition, segment function may not always reflect changes in myocardial blood flow.

Animals↗

Amyloidosis associated with juvenile rheumatoid arthritis.

Clinical and pathological findings are reported in a Japanese girl who died of secondary amyloidosis associated with juvenile rheumatoid arthritis two years after the onset of symptoms. The patient had intermittent high fever, rheumatoid rash, polyarthralgia, and hepatosplenomegaly. The joints showed the typical histologic changes of juvenile rheumatoid arthritis. Amyloid deposition was found in various tissues; however, remarkable deposition of amyloid was observed in the gastrointestinal tract, especially in the ileum. The amyloid protein in this patient was identified as protein AA using the methods of potassium permanganate treatment and the peroxidase-antiperoxidase unlabeled antibody technique.

Amyloidosis↗

Serum uric acid levels among thirty-four thousand people in Japan.

During 1978 a survey was carried out on 34 036 people in Nagano Prefecture, Japan, in an epidemiological study of hyperuricaemia; 15 713 males and 18 324 females were examined by means of our health examination car. The subjects of the survey were all volunteers. The results have shown that the serum uric acid (SUA) levels were related to sex and age. The male group had a mean SUA level of 5.82 mg/dl (range 0.9 to 11.8 mg/dl, standard deviation 1.14 mg/dl) (0.35, range 0.05-0.7, SD 0.07 mmol/l), and the female group had a mean of 4.33 mg/dl (range 0.5 to 9.7 mg/dl, standard deviation 0.91 mg/dl) (0.26, range 0.03-0.58, SD 0.05 mmol/l). The distribution curve for SUA was almost normal in both sexes. Lower levels of SUA were found in males from the 2nd to the 6th decade, but they increased again after the 7th decade. In females they gradually decreased and were at the lowest in the 4th and 5th decades, and then increased again. The values were always lower in females than males with the difference ranging from 1.84 to 0.81 mg/dl (0.11-0.05 mmol/l).

Adolescent↗

Leiomyoma of the left posterior tibial artery: a case report.

A case of leiomyoma of the left posterior tibial artery is presented. This tumor produced aneurysmal dilatation of the artery and was treated successfully by surgery. This may be the first documented case of a benign smooth muscle tumor, although nearly 100 leiomyosarcomas arising from large arteries and veins have been described in the literature.

Aged↗

Relationship between impairment of prenatal brain growth and family history of psychosis in schizophrenia.

Recently McNeil et al. (1993b), showed that schizophrenics had smaller head circumference (HC) at birth than controls. This small head size at birth was observed more commonly among schizophrenics without a family history of psychosis than among familial schizophrenics, suggesting that some prenatal environmental factors, rather than genetic factors, are related to the impaired brain growth in utero. We attempted to replicate this finding in 100 Japanese schizophrenics (DSM-III-R), using contemporaneous data on body measures at birth. Conversely, in the current study, HC at birth was found to be significantly smaller in schizophrenics with a family history of psychosis (N = 19) than those without (N = 81). A multiple regression analysis, controlling for gender, gestational age, maternal age, birth order and year of birth, yielded an overall reduction of about 1 cm in HC at birth among familial schizophrenics compared with non-familial schizophrenics. When HC at birth in family history positive and negative groups was compared separately with the local population norms with adjustment for gender and gestational age, familial and non-familial schizophrenics were both found to have significantly smaller HC at birth, although the difference was less marked for the latter. These results suggest that schizophrenics have delayed cerebral development in utero, and that genes which operate on prenatal neurodevelopment may play an important role in the aetiology of schizophrenia, although it is possible that some environmental factors may also be involved in the impaired brain growth.

Adult↗