Biomedical subjects
Publications and source records attributed to T Sugihara.
A case of a branchial cyst with a high amylase activity of the cyst fluid was found in a 58-year-old female. The literature on branchial cysts with high amylase activity is reviewed. Amylase that showed high activity in the cystic fluid was revealed to be due to the salivary isoenzymes (S3 and S4) which migrated more to the anodic side on electrophoresis.
We found a new thrombophilic tendency in a family with protein S deficiency. The propositus, a 38-year-old Japanese man, is an offspring of consanguineous marriage and suffered from recurrent episodes of thromboembolism. Hemostatic studies, including platelet counts, platelet aggregation, assays of coagulation factors, and plasminogen activity were all within normal limits. The levels of antithrombin III, alpha 2-macroglobulin, protein C, and protein C inhibitor were also normal. However, functional protein S activity in plasma was markedly decreased (9%) in the propositus. The family study revealed that the reduced levels of functional protein S, less than 5% to 29% of normal (normal range: mean +/- 2 SD of 15 normal adults were 44 to 180%), were found in 11 members of this family over three generations. Six of 11 members had severe protein S deficiency (less than 5%), whereas five had partial deficiency. Four of eight adults with protein S deficiency had recurrent episodes of thrombosis. Immunologic levels of protein S antigen were variable in this family and did not correlate closely with the functional levels. These results suggest that the recurrent thrombotic disease in this family appears to be associated with an inherited deficiency of functional protein S.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Plasma lipids and red cell lipids were determined in hereditary spherocytosis (HS), 15 unsplenectomized and eight splenectomized patients. Plasma lipids (cholesterol: total, free and high density lipoproteins, free fatty acids, and phospholipids) were markedly decreased in HS, especially in the unsplenectomized patients. Concomitantly, red cell membrane lipids (free cholesterol and phospholipids: total, phosphatidyl ethanolamine, sphingomyelin, phosphatidyl choline, and lysophosphatidyl choline) were also diminished. The plasma lipids stay low even after splenectomy although partially restored. Thus, decreased membrane surface, a hallmark of HS, could be partly attributed to the diminished membrane lipids induced by plasma lipid abnormalities in the patients.
When mice are forced to swim a restricted space, they will cease attempts to escape and adopt a characteristic immobile posture. In this study, this immobility was reduced by antidepressants and monoamineoxidase inhibitors. We found that diazepam had the ability to enhance this immobility. It is well known that diazepam exerts its pharmacological effect at least in part through GABAergic functions. Muscimol and aminooxyacetic acid enhanced the immobility. In addition, semicarbazide, bicuculline, picrotoxin and pentylenetetrazol reduced the immobility and pretreatment with bicuculline decreased this enhancement with muscimol, aminooxyacetic acid and diazepam. It seems that GABAergic functions play some role in the mechanism of this immobility.
In a patient with lecithin: cholesterol acyltransferase deficiency, free cholesterol was markedly increased, and esterified cholesterol was diminished. In the patient's plasma, an increase in phosphatidylcholine (PC) and a decrease in sphingomyelin were observed. Concomitantly, an increase in a shorter acyl chain 16:0 was noted in PC, sphingomyelin and phosphatidylethanolamine (PE). In contrast to these results, longer chains such as 22:0 and 24:0 were decreased, especially in sphingomyelin. Unsaturated double bonds such as 18:1 was also increased in PC and PE. In the red-cell membrane lipids, the increase in free cholesterol was counteracted by an increase in PC and by a decrease in sphingomyelin and PE, reflecting changes in the patient's plasma lipids. Increased 16:0 (in PC) and decreased 18:0 and 24:0 were observed. The increased plasma free cholesterol due to metabolic defect (lecithin: cholesterol acyltransferase deficiency) led to decreased red-cell membrane fluidity. This effect appeared to be counteracted by changing phospholipid composition (increased PC and decreased sphingomyelin and PE), by increasing shorter chains (16:0), by decreasing longer chains (18:0 and 24:0) and by increasing unsaturated double bonds (18:2). These results can be interpreted as a self-adaptive modification of lecithin: cholesterol acyltransferase deficiency-induced red-cell membrane abnormalities, to maintain normal membrane fluidity. This speculation was supported by the ESR spin-label studies on the patient's membrane lipids. The normal order parameters in intact red cells and in total lipid liposomes were decreased if cholesterol-depleted membrane liposomes were prepared. Thus, the hardening effect of cholesterol appeared to be counteracted by the softening effects described above. Overall membrane fluidity in intact red cells of the lecithin: cholesterol acyltransferase-deficient patient was maintained normally, judged by order parameters in ESR spin-label studies.
Red cell membrane metabolism in familial lecithin:cholesterol acyltransferase (LCAT) deficiency was investigated. The family presented here is the third case discovered in Japan. An increase of free cholesterol was observed in the red cell membranes, concomitant with increased phosphatidyl choline. Osmotic fragility of the patient's red cells was diminished rather than increased. Red cell survival (51Cr T1/2) was shortened (15 days). Sodium influx was markedly decreased, although sodium efflux, both ouabain-sensitive and ouabain-insensitive, was normal. The activity of acetyl-cholinesterase as a marker of the outer leaflet of the red cell membranes was decreased, while the activity of glyceraldehyde-3-phosphate dehydrogenase as a marker of the inner leaflet was normal. No abnormalities of adenosine triphosphatases in red cell membranes were observed. These results suggest that the alteration of cholesterol metabolism in the plasma of LCAT deficiency increases the red cell membrane cholesterol and affects the functions of the red cell membranes, especially of the outer leaflet, which may result in decreased sodium influx.
A possible mechanism of the formation of microspherocytosis in unsplenectomized patients with hereditary spherocytosis (HS) was investigated in relation to lipid metabolism in plasma and in red cells of these patients. Plasma lipids (total cholesterol, free cholesterol, high density lipoprotein cholesterol, free fatty acids, and phospholipids) were markedly reduced in unsplenectomized HS patients with microspherocytosis. Red cell membrane lipids (free cholesterol and phospholipids such as phosphatidyl ethanolamine, sphingomyelin, phosphatidyl choline, and lysophosphatidyl choline) were also decreased in these unsplenectomized HS patients. After splenectomy, microspherocytosis disappeared concomitant to substantial normalization of plasma and red cell membrane lipids. These observations suggest that plasma lipid decrement in the unsplenectomized HS patients is at least one of the causative factors in pathogenesis of the formation of microspherocytosis. So-called "splenic conditioning" may not imply a physical "loss" of membrane by fragmentation or pitting of the once-formed HS red cells in the peripheral circulation. Instead, the decreased plasma lipids in the presence of the spleen may affect the de novo synthesis of red cell membrane lipids, resulting in the formation of microspherocytosis.