Search PubMed⌕ Search

Biomedical subjects

T Okabe

Publications and source records attributed to T Okabe.

At least 343 records · Page 19Linked to original sources
PubMed1987

Cytosynalin: a Mr 35,000 cytoskeleton-interacting and calmodulin-binding protein.

A Mr 35,000 calmodulin-binding protein, which also possesses the ability to interact with a number of cytoskeletal elements, was purified from bovine synaptosomal membranes, using hydroxylapatite and phosphocellulose column chromatography. We call this protein "cytosynalin," which is derived from a combination of the words "cytoskeleton" and "synapsis." Indirect immunofluorescent staining of cytosynalin revealed that it is distributed throughout neural cells including in dendrites, varicosities, and growth cones. In 3T3 cells, cytosynalin is located on the inner surface of the plasma membrane. The staining pattern of cytosynalin observed with anti-cytosynalin antibodies was similar to that observed with antibodies against calspectin (nonerythroid spectrin or fodrin). Cytosynalin binds to calspectin and to tubulin and actin filaments, as determined by binding assays, turbidity measurements, low-shear viscometry, and electron microscopy. Furthermore, after heating at 90 degrees C for 5 min, cytosynalin retains its binding activity toward calmodulin and cytoskeletal elements. These results lead to the conclusion that cytosynalin is colocalized with calspectin at the inner surface of the plasma membrane, probably in association with other cytoskeletal elements.

Amino Acids↗
PubMed1987

Basal, oxytocin-, and insulin-stimulated glucose oxidation in human endometrium.

Samples of endometrium from regularly cycling women (28 +/- 2 days cycle) were assayed for [U-14C]glucose oxidation activity in the presence or absence of 100 nM oxytocin or 1.7 nM insulin. The basal rate of glucose oxidation in the tissues obtained from women in early and midfollicular phase and late luteal phase was approximately 125 pmol/(h X mg tissue). Late follicular and midluteal phases had higher basal rates, up to 400 pmol/(h X mg tissue). Oxytocin increased glucose oxidation by 50-100 pmol X h-1 X mg-1 in early and midfollicular phase and in early luteal phase endometrial fragments. Insulin did not stimulate glucose oxidation in these tissues. In samples of late luteal phase, glucose oxidation was stimulated by both oxytocin and insulin. High and low basal glucose oxidation activity in the endometrium corresponded, respectively, to reported periods of high and low plasma estradiol in normal menstruating women. In contrast, oxytocin stimulated glucose oxidation in endometria from women with anticipated low plasma estradiol.

Endometrium↗
PubMed1987

Chemotactic factors present in the supernatants of cultured sarcoid granulomas.

The present study was undertaken to test whether cultured lymphocytes and epithelioid cells from sarcoid granulomas obtained from patients with active stage 2 sarcoidosis produced chemotactic factors (CF) for leukocytes as assessed by modified Boyden's method. The results indicate that: (1) CF for mononuclear cells and for neutrophils were detected in supernatants from cultured sarcoid granulomas; (2) similar activity was detected in culture supernatants from both lymphocytes and epithelioid cells; (3) CF present in the supernatants of cultured epithelioid cells were similar physically to those which other investigators have disclosed to be released by alveolar macrophages, (4) CF in the supernatants of cultured lymphocytes were similar to the lymphokines based on an estimation of molecular size; (5) neutrophils from patients with sarcoidosis were less responsive to zymosan-activated sera and did not respond well to CF derived from their own granuloma, whereas mononuclear cells from sarcoid patients responded well to CF. In conclusion, CF are present in the supernatants of cultured sarcoid granulomas and they appear to preferentially attract mononuclear cells from sarcoid patients.

Cells, Cultured↗
PubMed1987

Dissolution of mercury from amalgam into saline solution.

Dissolution of mercury from amalgams and some intermetallic compounds found in the amalgam structure, such as gamma 1, gamma 2, and beta 1, was examined during one week of aging in 0.9% NaCl solution at 37 degrees C. The amount of mercury released from gamma 1 (30.2 micrograms/cm2) was at least 13 times that released from amalgam (0.5-2.2 micrograms/cm2) and five times that released from beta 1(5.7 micrograms/cm2). Gamma 2 released the least amount of mercury (0.46 micrograms/cm2). The study revealed that as high as 55% of the mercury ions liberated from the amalgams and the amalgam phases was adsorbed onto the walls of the vials in which the specimens were aged.

Adsorption↗
PubMed1987

Time-dependent dissolution of amalgams into saline solution.

The dissolution of mercury, silver, and copper from polished and unpolished surfaces of low- and high-copper amalgams into saline was investigated with respect to time via atomic absorption spectrophotometry. Greater amounts of mercury and silver were released from unpolished than from polished surfaces. Ion release was greatest during the first three hours after trituration of all amalgams. The rate of dissolution of ions from amalgams into saline is considered to be very low once the amalgam has set, and is probably inhibited by the formation of a surface film formed during immersion.

Copper↗
PubMed1987

Surface characterization of amalgams using X-ray photoelectron spectroscopy.

This study is the first to report on the use of x-ray photoelectron spectroscopy (XPS or ESCA) for studying the surface films (less than 10 nm thick) of aged amalgams. The concentrations and electron binding energies of the elements on the surfaces of four different amalgams aged for 20 min, one day, seven days, and 30 days were determined quantitatively. For comparison, the bulk compositions of the amalgams aged for seven days were also determined after removal of approximately 5 nm of material from the surface by argon-ion-sputtering. The XPS data revealed that the surface films of aged zinc-containing amalgams were not a simple oxide but were primarily composed of a (hydrated) tin and zinc oxy-hydroxide, whereas, in the zinc-free amalgams, the surface films were primarily a tin oxide. The concentration of mercury in this thin surface film after aging was depleted. This suggests that tin and/or zinc preferentially diffused to the surface and combined with oxygen, forming a surface film and diluting the mercury concentration in the surface. Another probable explanation for the depleted mercury is that a minimal amount of mercury in the surface film evaporated during the aging.

Copper↗
PubMed1987

Role of renal catecholamines in the control of sodium and water excretion: lack of natriuresis by endogenous dopamine in the rat kidney.

The physiological role of dopamine in renal Na and water excretion was studied in rats treated with L-3,4-dihydroxyphenylalanine (L-DOPA), haloperidol or 6-hydroxydopamine for 1 week. Daily-pooled urine samples, plasma, and kidneys were obtained from the experimental groups and untreated controls. Urinary dopamine was markedly elevated in L-DOPA-treated and transiently decreased in haloperidol-treated rats. Urinary epinephrine, but not norepinephrine was increased in the L-DOPA and haloperidol groups. However, there was no significant difference in urine volume, urinary Na, urinary K, plasma Na and K levels between the experimental groups and controls, except for 6-hydroxydopamine-treated rats. They showed a definite increase in urinary volume, Na, K and aldosterone excretion, whereas the renal norepinephrine and epinephrine content was reduced. Urinary cAMP and Na-K ATPase activity were also similar in all groups, whereas renal cAMP content and aromatic amino acid decarboxylase activity were significantly increased in the L-DOPA and haloperidol groups, suggesting an activated catecholamine synthesis in the kidney. [3H]haloperidol binding was also increased by the L-DOPA and 6-hydroxydopamine administration, but the half maximal displacement dose was similar in all groups (6.4 x 10(-9)mol/l), indicating an increase in the number of dopamine binding sites. These results indicate that 1) in contrast to the pharmacological effect of dopamine, locally-formed dopamine has no direct natriuretic action in the kidney; 2) an enhanced production of dopamine in the kidney does not suppress aldosterone secretion.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

Familial hyper-angiotensin converting enzyme (ACE)-emia: increased production of ACE by monocyte-macrophage.

We report here a familial clustering of elevated serum angiotensin converting enzyme (ACE) levels. The patient was a 58-year-old Japanese female. She had been in excellent health until the age of 45, when she noticed a decrease in visual acuity of her left eye. Despite intensive therapy under the diagnosis of occulusion of the central retinal vein, she lost her visual acuity at the age of 45. Thereafter, she has been in excellent health. The only abnormality found in this case has been a markedly elevated level of serum ACE (625 n mol/min/ml; normal range; 22-40 n mol/min/ml of serum). Her blood pressure was within normal limits (140/80 mmHg). There was no evidence for the diagnosis of sarcoidosis, Gaucher's disease, leprosy, hyperthyroidism, diabetic retinopathy, or liver disease. One of her two sisters also showed a marked increase in serum ACE activity (303 n mol/min/ml), and remarkably high levels of serum ACE (276 and 294 n mol/min/ml) were demonstrated in both of two sons of this sister. All the members of this family have been in excellent health. The serum ACE activity was activated by chloride and cobalt ions, and inhibited by EDTA, captopril and rabbit antiserum to purified human plasma ACE. Thus, our study showed a familial clustering of "hyper-ACE-emia", and the disorder appears to have been inherited as an autosomal dominant trait.

Cells, Cultured↗
PubMed1987

Production of colony-stimulating factor by sarcoid granulomas in vitro.

To examine whether sarcoid epithelioid cells of granulomatous lesions produce colony-stimulating factor (CSF), a growth factor of monocyte-macrophage series, the primary culture of sarcoid epithelioid cells was carried out from 16 biopsied lymph nodes which contained sarcoid granulomas, CSF activity was demonstrated at high titer in the conditioned media from all the epithelioid cell cultures. The conditioned medium of the epithelioid cell culture was harvested, concentrated by Amicon YM-10 membrane, and loaded on a Sephadex G-75 column. Two distinct peaks of CSF activity were noted just before and after bovine serum albumin region. The molecular weights were estimated at about 75,000 and 36,000, respectively. Both CSF fractions stimulated colony formation by murine bone marrow cells. The lower molecular weight CSF was active on human bone marrow cells, but the higher molecular weight CSF did not stimulate colony formation by human bone marrow cells.

Chromatography, Gel↗
PubMed1987

Effect of recombinant human granulocyte colony-stimulating factor on hemopoietic cells in serum-free culture.

The effect of recombinant human erythropoietin (Ep) and granulocyte colony-stimulating factor (G-CSF) on colony formation by human hemopoietic progenitors was examined in a methylcellulose culture system. In the serum-containing culture system, granulocyte-macrophage (GM) colonies and erythroid bursts were formed by non-phagocytic mononuclear cells only in the presence of Ep. To exclude the effect of the serum, which may have hemopoietic factors, we replaced the serum with bovine serum albumin, transferrin, and lipids. In serum-free culture, recombinant Ep supported erythroid colony formation, but not erythroid burst formation. While G-CSF could support the proliferation of macrophages (30%) as well as neutrophils in the presence of fetal calf serum (FCS), it supported mainly neutrophils (97%) in serum-free culture. In this culture system, G-CSF could not induce burst formation in the presence of Ep. By using a serum-free culture system, we found that human G-CSF is a lineage-specific hemopoietic factor which acts on granulocyte-committed progenitor cells and not on early erythroid progenitor cells.

Blood Proteins↗
PubMed1987

Cloning of granulocyte colony-stimulating factor cDNA from human macrophages and its expression in Escherichia coli.

Human granulocyte colony-stimulating factor (hG-CSF) cDNA was cloned, by using a synthetic oligonucleotide probe, from an Okayama-Berg cDNA library of lipopolysaccharide-stimulated human peripheral blood macrophages. The cDNA encodes a polypeptide with an amino acid sequence which completely matches that of the known polypeptide with hG-CSF activity derived from human tumor cell lines. Expression in E. coli of high levels of the protein (about 10% of total cellular proteins) was accomplished under control of the trp promoter, and the purified protein was proved to have hG-CSF activity. Our data provide evidence that human peripheral blood macrophages do produce hG-CSF mRNA when stimulated exogenously, suggesting they are the producer of naturally occurring hG-CSF.

Base Sequence↗
PubMed1987

[Adult Wilms tumor: a case of prolonged survival achieved by multimodal treatment].

Wilms tumor is one of the most common malignant neoplasms in children. In the last 2 decades the survival rate of children with this disease has dramatically increased. However, in adults, the guideline for its management is less clear. We herein report the prolonged survival of a patient with advanced adult Wilms tumor after treatment with chemotherapy, irradiation and operations. Adult Wilms tumor should be treated aggressively with a well-timed combination of surgery, chemotherapy and radiotherapy (i.e., multimodal treatment), even if the stage of the disease was advanced. Thereby, we suspect that the prognosis of adult Wilms tumor would be markedly improved.

Adult↗
PubMed1987

Recombinant human granulocyte colony-stimulating factor repairs the abnormalities of neutrophils in patients with myelodysplastic syndromes and chronic myelogenous leukemia.

We examined the in vitro effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on neutrophil anomalies in 20 patients with myelodysplastic syndromes (MDS) and eight patients with chronic myelogenous leukemia (CML). Neutrophil alkaline phosphatase (NAP) activity was determined in nine MDS patients and eight CML patients by a scoring method. NAP scores were decreased in six of the nine patients with MDS and in all of the patients with CML. In all patients with these diseases, NAP scores increased by incubating the blood with rhG-CSF. An increase in NAP scores by rhG-CSF was observed even at a concentration of 1 U/mL in patients with MDS but was observed only at higher concentrations (1,000 to 10,000 U/mL) in patients with CML. Significant increases in NAP scores occurred at 12 hours' incubation in patients with MDS, whereas the increase was more gradual in patients with CML. This time course difference was thought to be due mainly to the difference in cell populations of circulating myeloid cells between MDS patients and CML patients. Induction of NAP activity by rhG-CSF in patients with both these diseases was suppressed by the addition of inhibitors of RNA or protein synthesis. Neutrophil superoxide anion (O2-) production induced by N-formyl-methionyl-leucyl-phenylalanine (fMLP) was determined in the other 11 patients with MDS. This neutrophil function was decreased in seven of the 11 patients with MDS, normal in two patients, and increased in two patients. Preincubation with rhG-CSF caused a significant increase in fMLP-induced O2- production in nine of the 11 patients with MDS. rhG-CSF enhanced this neutrophil function in a time- and dose-dependent manner, and maximal stimulation was observed at 2,000 to 4,000 U/mL of rhG-CSF and at five to ten minutes' incubation. The present results show that rhG-CSF is able to repair at least in part the neutrophil anomalies in these patients, and our data, especially for patients with MDS, suggest the clinical usefulness of rhG-CSF for this preleukemic disorder.

Alkaline Phosphatase↗
PubMed1987

Human granulocyte colony-stimulating factor produced by Escherichia coli shortens the period of granulocytopenia induced by irradiation in mice.

Daily administration of purified human granulocyte colony-stimulating factor produced by E. coli (Hu-G-CSF) accelerated the recovery from neutropenia induced by total-body irradiation in mice. Granulocyte-macrophage progenitors assayed as colony-forming unit granulocyte/macrophage (CFU-GM) in spleen were markedly increased in number by Hu-G-CSF, and the accelerated recovery from neutropenia may be due to the stimulation of granulocytopoiesis by the G-CSF from progenitor cells.

Agranulocytosis↗