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Biomedical subjects

N Tsushima

Publications and source records attributed to N Tsushima.

At least 37 records · Page 2Linked to original sources
PubMed1990

Effects of ketanserin on microhemodynamics and hemorheology in patients with essential hypertension.

Ketanserin, a serotonin antagonist, has recently been developed. This agent produces antihemagglutination and dilation of blood vessels. Blood pressure is also lowered by ketanserin. We investigated the effect of ketanserin on microhemodynamics and hemorheology in essential hypertension. Twenty patients with essential hypertension (8 males; 12 females; average age +/- SE-56.2 +/- 2.5 years). A single dose of 10 mg ketanserin was given orally to each patient, without breakfast, on the experiment day. Ketanserin treatment resulted in: redution in systolic and diastolic blood pressure; significant decrease in heart rate; increase in arteriole and venule internal diameters; increase in blood flow velocities and blood flow volumes; significant decreases in whole blood viscosities at high shear rate (94.5 sec-1) and at low shear rate (0.376 sec-1), with no change in plasma viscosities; significant shortening of plasma passage times; and marked decreases in blood concentrations of total protein, albumin, and globulin. These data suggest that ketanserin beneficially affects microhemodynamics and hemorheology.

Arterioles↗
PubMed1990

Comparison of delta-aminolaevulinic acid dehydratase activity in chick liver during sex steroid hormone dependent primary and secondary stimulation.

1. Comparative study on primary and secondary stimulation of hepatic delta-aminolaevulinic acid dehydratase (ALAD) (EC 4.2.1.24) was carried out after oestradiol-17 beta and/or testosterone administration in immature female chicken. 2. When 2 mg/day oestradiol was administered to birds for 15 days successively, hepatic total ALAD activity increased to 170% by day 15 of primary stimulation, whereas a more rapid increased rate was observed within day 3 of secondary stimulation and thereafter the hepatic ALAD activity maintained the same high level from day 3 to day 15. 3. Testosterone (2 mg/day) alone decreased hepatic total ALAD activity during both primary and secondary stimulation. 4. When testosterone (0.25-10 mg/day) was injected into birds in combination with 2 mg oestradiol for 15 days during primary and secondary stimulation, only an antagonistic effect of testosterone on oestradiol-stimulated total ALAD activity in liver was observed independently of the testosterone amount administered. However, the extent of suppression of hepatic ALAD activity by testosterone during primary stimulation was markedly different from that of secondary stimulation.

Animals↗
PubMed1990

Kinetics of internalization and cytotoxicity of transferrin-neocarzinostatin conjugate in human leukemia cell line, K562.

Human serum transferrin was conjugated with an anticancer-active polypeptide, neocarzinostatin, by using N-succinimidyl 1-3-(2-pyridyldithio)propionate. The conjugate consisted of 1.8 mol of neocarzinostatin per 1 mol of transferrin on average and retained cytotoxic activity against human tumor cells. This conjugate was capable of binding to the transferrin receptor of human myelogenous leukemia K562 cells and was internalized by endocytosis. The LD50 values of the conjugate and neocarzinostatin alone in the presence of excess native bovine transferrin were 0.20 microgram/ml and 1.80 micrograms/ml, respectively, suggesting that the effect of the conjugate was greater than that of neocarzinostatin alone. A pulse-chase experiment using 125I-labeled conjugate revealed that 25% of the internalized conjugate was degraded in lysosomes and the rest was recycled back to the cell surface without degradation. About 75% of this conjugate recycled back to the cell surface in 18.3 min (3.4 min for receptor binding and 14.9 min for recycling to the cell surface through the acidosomes), while the rest was delivered from the cell surface to the lysosome in 19.6 min. This phenomenon was confirmed by chasing the radioactivity in subcellular fractions separated by Percoll density gradient centrifugation. Therefore, it was concluded that this conjugate is internalized specifically by transferrin receptors and is at least partly transferred to and accumulated in lysosomal compartments, resulting in the inhibition of cellular DNA synthesis.

Antibiotics, Antineoplastic↗
PubMed1990

[Preoperative aspects of blood rheology in patients who developed multiple organ failure following cardiac surgery].

The relationship between preoperative hemorheology and postoperative course was studied in 38 patients who had undergone open heart surgery for valvular diseases (mean age, 53 +/- 2 S.E. years). Twelve patients had multiple organ failures (MOF) one week after surgery, while the remaining 26 patients were in satisfactory condition. The hematocrit (Ht) was 34.8 +/- 1.6 S.E.% in patients with MOF and it was 40.4 +/- 0.9 S.E.% in patients without MOF. The difference was significant. Blood viscosities (eta) at shear rates of 94.5 sec-1 and 0.376 sec-1 also were significantly lower in patients with MOF compared with those without MOF. However, oxygen delivery (Ht/eta at a shear rate of 94.5 sec-1) in terms of hemorheology, plasma viscosity, and erythrocyte deformability were not significantly different between the two groups. These data suggest that patients with a low hematocrit and a low viscosity are likely to suffer from MOF following surgery.

Adult↗
PubMed1990

[Percutaneous transluminal angioplasty of the subclavian artery].

We reported a case of subclavian artery stenosis successfully treated by percutaneous transluminal angioplasty (PTA). He suffered from left arm claudication and proximal subclavian artery stenosis. The stenosis and symptoms disappeared soon after PTA. No complications occurred. Patients with hemodynamically significant stenoses, symptoms and signs should be considered for PTA.

Angioplasty, Balloon↗
PubMed1989

[A case of cutaneous T cell lymphoma improved with local administration of tumor necrosis factor].

A 63-aged woman with cutaneous T cell lymphoma successfully treated with local administration of tumor necrosis factor (TNF) was reported. She was admitted to our hospital because of tumors and subcutaneous nodules on her bilateral inner thigh. A pathological study of her skin of right inner thigh showed mononuclear atypical cells with hyperlobulated nuclei. In peripheral blood the same lymphoid cells were found. Immunohistochemical staining of these cells was positive for OKT-3 and OKT-4, but negative for OKT-8. No lymph node swelling and no visceral involvement were detected by a CT scan and a Echography of the chest and the abdomen. A diagnosis of cutaneous T cell lymphoma was made (stage IIb TNM classification). Although the chemotherapy of VEPA and CHOP was done, about 70% (PR) of the bilateral inner thigh tumors were retracted. Owing to the interstitial pneumonia aroused in the period of bone marrow suppression and cardiomyopathy after chemotherapy, we gave up further systemic chemotherapy. And then the local administration of TNF was done and the disappearance of the bilateral inner thigh tumors was obtained. Our therapy with local administration of TNF for CTCL in the first report.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1989

[Clinical studies of cefpodoxime proxetil in pediatric field].

Clinical studies of cefpodoxime proxetil (CPDX-PR), a new cephem antibiotic, were carried out in 60 patients in the pediatric field. The overall efficacy rate on 54 patients with various infections was 98.1%, and few side effects, all of them very mild, were developed in 6 of 60 patients (10%). It was concluded that CPDX-PR was one of the most useful antibiotics in the pediatric field because of the high efficacy rate and the safety.

Acute Disease↗
PubMed1988

Comparison of sex hormone dependent induction of delta-aminolevulinic acid dehydratase in chick liver and oviduct.

1. Comparative study on induction of hepatic and oviduct delta-aminolevulinic acid dehydratase (EC 4.2.1.24, ALAD) was performed following estradiol-17 beta and/or testosterone administration in immature female chicken (Gallus domesticus). 2. The lowest amount of estradiol for maximal induction of hepatic and oviduct ALAD activity was 2 mg/day/bird. 3. When estradiol of 2 mg/day/bird was administered for 15 days successively, induction extent of oviduct ALAD molecule was markedly larger and became approximately 144-fold in comparison with that of liver. Testosterone (2 mg/day/bird) alone did not induce both hepatic and oviduct ALAD activity. 4. Synergistic and antagonistic effect of testosterone on estradiol-induced total ALAD activity in oviduct was dependent on testosterone amount administered, whereas testosterone antagonized the inductive effect of estradiol on liver ALAD activity, independently of its amount.

Animals↗
PubMed1988

Successful treatment of a VIPoma by continuous subcutaneous infusion of somatostatin analogue (SMS 201-995).

A case with WDHA syndrome due to VIPoma is reported. Injection of somatostatin analogue SMS 201-995 was followed by prompt suppression of vasoactive intestinal polypeptide levels (VIP), decreased stool volume, and restoration of the serum potassium concentration to normal. Long-term treatment with SMS 201-995 for up to 20 weeks produced excellent clinical control and a decrease in tumour size. No adverse effects were noted except for localized pain at the site of injection. This was overcome by using a continuous subcutaneous infusion pump which also enabled the effective daily dosage to be reduced and thereby adverse reactions to be avoided.

Female↗
PubMed1988

Study on reaction of subpapillary venous plexus in patients with arterial occlusive diseases of lower extremity by reflective spectrophotometry.

The reactions of the subpapillary venous plexus were observed by analyzed fractional blood volume of tissue (Vb) in patients with arterial occlusive diseases, Fontaine's stage I-II, using the reflective spectrophotometer. The sole skin of 11 normal subjects, 17 patients with arteriosclerosis obliterans (ASO), and 14 patients with thromboangiitis obliterans (TAO) were scanned by the light reflectance of four specially selected wavelengths, including isobestic points (586 and 569 nm) and peaks in the spectra of oxyhemoglobin and deoxyhemoglobin (577 and 560 nm) in referring to time. Sampling area was the subpapillary venous plexus histologically because the depth for receiving reflectance is about 1.0 mm from the sole skin surface. One series observations was divided into five steps depending on the modes of combination of the applied pressure to ankle cuff and tilting. The Kubelka-Munk equation was utilized to calculate blood volume (Vb). It is concluded that the patients with ASO might have a dysfunction, not of the subpapillary venous plexus, but of the venular valve, whereas patients with TAO might have a dysfunction of both the subpapillary venous plexus and venular valve.

Adult↗
PubMed1988

Change of hematocrit and blood viscosity in cholesterol-fed rabbits.

In the cholesterol-fed rabbits, we observed that the whole blood viscosity was maintained at the normal level in spite of the decrease in hematocrit. This phenomenon suggests that there exists some visco-regulatory mechanism, and we could simulate it by a simple integration type model.

Animals↗
PubMed1987

Effects of elastase on the stiffness and elastic properties of arterial walls in cholesterol-fed rabbits.

The effect of cholesterol feeding and elastase administration on the arterial stiffness and elastic properties was investigated in rabbits by pressure-diameter tests on excised thoracic aortas, common carotid and femoral arteries. Rabbits in groups RA and RB were fed 1% cholesterol diet for 14 weeks. Groups RC and RD were fed the cholesterol diet for the first 7 weeks, and then given regular chow for the last 7 weeks. In addition, rabbits in groups RB and RC were administered elastase daily for the last 7 weeks. Rabbits in group RE were fed the regular chow for 14 weeks and served as the control group. The arterial stiffness and the elastic modulus of wall material in the RA rabbits were generally higher than those in the control rabbits. Administration of elastase and/or feeding of the regression diet decreased the wall stiffness and elastic modulus significantly, although the effect of elastase did not appear clearly when used in combination with the regression diet. The cholesterol feeding decreased the ratio of thickness to wall radius, whereas the ratio was more or less increased by the elastase administration and/or the regression diet.

Animals↗
PubMed1987

Externalization of transferrin receptor in established human cell lines.

The externalization of transferrin receptors was found in established human tumor cell lines at the rate of 10-35 ng/hour/10(6) cells, when they were incubated with transferrin at 37 degrees C. This externalization is inhibited by lowering the incubation temperature to 4 degrees C or eliminating the ligand from the culture medium. Metabolic inhibitors such as sodium azide, colchicine, cytochalasin B and chloroquine also decreased the rate of externalization. Almost 95% of released transferrin receptors were precipitated by centrifugation at 100,000 x g for 30 min, suggesting that transferrin receptor is externalized into the medium as a vesicular form.

Biomarkers, Tumor↗
PubMed1987

Serum transferrin receptor as a new index of erythropoiesis.

Serum transferrin receptors were measured by a sandwich radioimmunoassay procedure in patients with iron deficiency anemia, autoimmune hemolytic anemia and aplastic anemia. The mean circulating transferrin receptor concentration of normal subjects and patients with iron deficiency anemia, autoimmune hemolytic anemia and aplastic anemia are 253 +/- 82 ng/mL, 730 +/- 391 ng/mL, 1,426 +/- 1,079 ng/mL, and 182 +/- 39 ng/mL, respectively. The values for those with iron deficiency anemia and autoimmune hemolytic anemia were significantly higher than that of normal controls and the values for those with aplastic anemia were lower than that of normal controls. After iron supplementation in iron deficiency anemia, the serum transferrin receptor values increased twofold over those of pretreatment values. This increase parallels an increase in peripheral reticulocytes. Therefore, the number of circulating transferrin receptors in anemic patients may reflect the level of bone marrow erythropoiesis and is a potentially useful new index for red cell production.

Anemia↗
PubMed1986

Circulating transferrin receptor in human serum.

Circulating transferrin receptor has been detected in human serum with a sensitive immunoassay. The mean concentrations of the serum transferrin receptor in healthy males and females were 251 +/- 94 (mean +/- SD) ng/ml and 256 +/- 99 ng/ml, respectively. The serum receptor concentration in patients with haematological malignancies, including acute leukaemia, multiple myeloma and malignant lymphoma, varied widely, from normal to 1100 ng/ml. A single band with an approximate molecular weight between 80,000 and 100,000 daltons was obtained by polyacrylamide gel electrophoresis-immunoblotting analysis of serum.

Acute Disease↗