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Biomedical subjects

F Takaku

Publications and source records attributed to F Takaku.

At least 307 records · Page 17Linked to original sources

Molecular cloning and characterization of a Ca2+ + Mg2+-dependent adenosine triphosphatase from rat cardiac sarcoplasmic reticulum. Regulation of its expression by pressure overload and developmental stage.

To investigate the regulation of expression of cardiac Ca2+ + Mg2+-dependent ATPase (Ca2+-ATPase) in sarcoplasmic reticulum (SR), we isolated cDNA (pHA6) encoding a Ca2+-ATPase of rat cardiac SR. The clone consisted of 2,311 mRNA-derived nucleotides, which covered half the coding region and the entire 3'-untranslated regions. The nucleotides and deduced amino acid sequences of pHA6 showed striking homology, 89 and 98%, respectively, to those of rabbit Ca2+-ATPase of the slow-twitch form. Northern blot analyses revealed that the mRNA levels of Ca2+-ATPase were decreased by pressure overload and became 32% of sham in 1 mo. During the developmental stage the mRNA levels were very low in the fetal period and steeply increased around birth. These changes in mRNA levels were correlated with the corresponding protein levels. These results suggest that the expression of cardiac Ca2+-ATPase in SR is regulated by pressure overload and the developmental stage, at least in part, at the pretranslational level.

Aging↗

Autoantibodies to the insulin receptor (B-10) can stimulate tyrosine phosphorylation of the beta-subunit of the insulin receptor and a 185,000 molecular weight protein in rat hepatoma cells.

The immunoglobulin G (IgG) fraction obtained from the serum of a patient (B-10) with type B insulin resistance and acanthosis nigricans stimulated both glucose oxidation in rat adipocytes and autophosphorylation of tyrosine residues in the beta-subunit of insulin receptors in H-35 hepatoma cells. Partially purified insulin receptor from H-35 cells, when incubated with B-10 IgG, had increased tyrosine kinase activity for a synthetic peptide sequentially similar to the site of tyrosine phosphorylation in pp60v-arc (the gene product responsible for cellular transformation by the Rous sarcoma virus). In H-35 cells, both B-10 IgG and insulin stimulated tyrosine phosphorylation in an endogenous 185,000 mol wt protein. This phosphoprotein may be similar to the cellular substrate for insulin in hepatoma and other cultured cell lines demonstrated by others. These results suggest that antiinsulin receptor antibodies (B-10) may initiate their insulin-like effects via tyrosine phosphorylation of the insulin receptor, activation of its tyrosine kinase activity, and phosphorylation of a cellular protein substrate of 185,000 mol wt.

Adipose Tissue↗

Infarct sizing after reperfusion by two-dimensional echocardiography and serum cardiac myosin light chain II in conscious dogs: dissociation between early left ventricular wall motion and ultimate infarct size.

The time course of recovery of left ventricular wall motion after coronary reperfusion and how that relates to anatomical infarct size, wall motion abnormality, and the amount of cardiac myosin light chain II release were evaluated in conscious dogs. One week after the implantation of hydraulic occluders on the left circumflex arteries, myocardial infarction was induced. Coronary reperfusion was performed 3 h after the occlusion in 9 dogs (R) and occlusion was sustained in 9 dogs (C). All dogs underwent serial 2-dimensional echocardiograms and determination of serum cardiac myosin light chain II. The infarct size was identified at 14 days. Systolic wall thickening at the center of the ischemic area (SWT) at 3 h was -7.7 +/- 2.8% (C), -9.9 +/- 3.0% (R). Systolic thinning was observed even at 14 days in C. Significant recovery of contraction was observed in R, but the improvement continued for as long as 2 days. SWT at 14 days was -1.5 +/- 2.8% (C) and 7.0 +/- 4.6% (R) (p less than 0.05). All of SWT or the extent of systolic thinning (EST) 3-hour and 14-day were correlated well with infarct size in C. In group R, 14-day SWT and 14-day EST correlated with infarct size but 3-hour SWT and 3-hour EST did not. Total release of serum cardiac myosin light chain II levels correlated well with infarct size (r = 0.88), 14-day SWT (r = -0.90) and 14-day EST (r = 0.89) in all dogs.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Role of prolactin in age-related change in serum dehydroepiandrosterone sulphate concentrations.

Serum dehydroepiandrosterone sulphate concentrations were measured in 70 patients with prolactinoma and in 54 patients with acromegaly with normal adrenocortical function. Compared with values in normal subjects of corresponding age, serum dehydroepiandrosterone sulphate levels were increased in 22 patients with prolactinoma (31%) and in 5 patients with acromegaly (9%). The four acromegalic patients who had elevated serum dehydroepiandrosterone sulphate levels had hyperprolactinemia. The mean serum dehydroepiandrosterone sulphate concentrations in patients with prolactinoma in each decade decreased with advancing age. There was a significant negative correlation between serum dehydroepiandrosterone sulphate concentrations and ages of the patients with prolactinoma. In all 8 women with prolactinoma as in 6 normal women, serum dehydroepiandrosterone sulphate levels declined definitely during the 9 years of follow-up despite persistent hyperprolactinemia. These results indicate that serum dehydroepiandrosterone sulphate levels are increased in a substantial number of patients with hyperprolactinemia, however, PRL per se may not play a significant role in the age-related change in serum dehydroepiandrosterone sulphate levels.

Acromegaly↗

Serum granulocyte colony-stimulating factor levels in healthy volunteers and patients with various disorders as estimated by enzyme immunoassay.

In order to better understand the patho-physiologic role of granulocyte colony-stimulating factor (G-CSF), we estimated its serum levels in healthy persons and patients with various disorders, using a newly developed enzyme immunoassay (Motojima et al). In 49 of 56 normal healthy persons (88%), the levels were beneath the sensitivity of the assay (less than 30 pg/mL), while in the remaining seven healthy persons, the levels ranged from 33 to 163 pg/mL. On the other hand, nine of 11 patients (82%) with idiopathic aplastic anemia (AA), one patient with Fanconi's anemia, six of 12 patients (50%) with myelodysplastic syndrome (MDS), five of 12 patients (42%) with acute leukemia without any blast cells in the blood (M4: one, M5: one, L1: one, and L2: two), six of 18 patients (33%) with chronic myeloid leukemia (CML), one of two patients with chronic lymphoid leukemia (CLL), two of four patients with lung cancer, one patient with cyclic neutropenia, two of seven patients with malignant lymphoma, and four patients with acute infection had G-CSF levels ranging from 46 pg/mL to greater than 2,000 pg/mL. Interestingly, a reverse correlation between blood neutrophil count and serum G-CSF level was clearly demonstrated for aplastic anemia (r = -.8169, P less than .01). Moreover, it was found that the G-CSF level rose during the neutropenic phase of cyclic neutropenia and after chemotherapy or bone marrow transplantation (BMT) in three patients with leukemia; also high G-CSF levels were positively correlated to blood neutrophil counts in some cases of infectious disorders and lung cancer. The cellular sources and the mechanisms for production and secretion of circulating G-CSF were not investigated in this study, but the data presented here strongly indicate that G-CSF plays an important role as a circulating neutrophilopoietin.

Acquired Immunodeficiency Syndrome↗

A new bioassay for human granulocyte colony-stimulating factor (hG-CSF) using murine myeloblastic NFS-60 cells as targets and estimation of its levels in sera from normal healthy persons and patients with infectious and hematological disorders.

[3H]thymidine uptake by NFS-60 cells in microcultures was found to increase in a linear fashion with the increasing doses of purified recombinant human granulocyte colony-stimulating factor (rhG-CSF). Such increases were found neither with rhG-CSF samples pretreated with rabbit anti-rhG-CSF serum nor with other human colony-stimulating factors such as granulocyte-macrophage colony-stimulating factor (hGM-CSF) or macrophage colony-stimulating factor (hM-CSF). Based on these findings, sera from normal persons and patients with severe infections or various hematological disorders were tested after dialysis using this system in order to determine whether G-CSF levels in sera can be estimated or not. In ten normal persons, five patients with acute myelogenous leukemia (AML M1, M2, and M3), five with myelodysplastic syndrome, and four with chronic myelogenous leukemia, no increases in [3H]thymidine uptake were found within the dose range of 0.4 microliters to 50 microliters. In contrast, linear dose responses parallel to a G-CSF standard curve were observed in one patient with a severe bacterial infection, four with aplastic anemia, two with acute myelomonocytic leukemia (AMMoL) (M4), and two with idiopathic neutropenia tested. From the standard curve, the probable levels of G-CSF were calculated as follows: approximately 200 pg/ml with infection, 130-220 pg/ml with aplastic anemia, 150 and 200 pg/ml with AMMoL, and 1120 and 1200 pg/ml with idiopathic neutropenia. The activities of sera were reduced by the anti-rhG-CSF serum pretreatment in the same way as documented in the case of rhG-CSF. Furthermore, the level in a patient with a severe infection became undetectable soon after elimination of the infection and blood neutrophil counts had returned to normal. These findings indicate that the microbioassay system will be useful for measuring circulating G-CSF levels which would fluctuate in accord with requirements for stimulating neutrophil production or with abnormal production of hG-CSF.

Adult↗

Modulation by retinoids and interferons of alkaline phosphatase activity in granulocytes induced by granulocyte colony-stimulating factor.

We have previously shown that a factor termed NAP-IF has the capacity to induce neutrophil alkaline phosphatase (NAP) in postmitotic granulocytes (PMGs). Recently, this factor found in cystic fluid of a human squamous cell carcinoma was shown to be identical to granulocyte colony-stimulating factor (G-CSF). In this study we examined whether NAP activity inducible with G-CSF could be modulated by other factors that are present in vivo or those that are known to induce differentiation of hemopoietic cells. Purified natural and recombinant G-CSF (nG-CSF and rG-CSF) induced NAP in PMGs from both normal individuals and patients with chronic myelogenous leukemia. Interferons (IFNs) suppressed expression of NAP by G-CSF. IFN-gamma was a potent inhibitor of G-CSF stimulation: IFN-gamma at 100 U/ml inhibited by greater than 90% the induction of NAP by G-CSF. In contrast, retinol (10(-6) M, a nearly physiological concentration) or all-trans-retinoic acid (10(-6) M) significantly enhanced NAP activity in vitro. Furthermore, the simultaneous addition of 10(-6) M retinol partially reversed the inhibitory action of IFN-gamma on the NAP induction by G-CSF. Our results suggest that NAP activity, which is often abnormal in a variety of diseases, may reflect G-CSF levels in vivo perhaps in concert with a number of other factors including IFNs and retinoids.

Alkaline Phosphatase↗

Clinical effects of recombinant human granulocyte colony-stimulating factor in leukemia patients: a phase I/II study.

A phase I/II study of recombinant human granulocyte colony-stimulating factor (rhG-CSF) in 24 leukemia patients was conducted at our institute. Recombinant human G-CSF (50-200 micrograms/m2/day) was administered i.v. In seven allogeneic bone marrow transplantation (BMT) recipients, treatment with rhG-CSF was started 5 days after BMT. Neutrophils began to increase within 3 days after the start of rhG-CSF administration in five of seven patients. The mean duration necessary for recovery of neutrophils to greater than 500/microliters was 11.3 days after BMT with rhG-CSF; 26.8 days is the figure for recovery without rhG-CSF from Japanese historical data. In seven out of eight patients who received rhG-CSF administration after the first remission-induction chemotherapy, the neutrophil counts increased from less than 300/microliters to greater than 4000/microliters within 10 days. Blasts did not increase in all patients including four acute nonlymphocytic leukemia (ANLL) patients. Severe infections such as septicemia and pneumonia, which were unable to be controlled by antibiotics only, were successfully treated with rhG-CSF and antibiotics. rhG-CSF either stimulated or inhibited myeloid leukemic cells in some refractory cases. Mild bone pain occurred in one patient while receiving rhG-CSF i.v. rhG-CSF seems to have the ability to shorten the period of neutropenia, prevent infections after allogeneic BMT and remission-induction chemotherapy for acute leukemia, and support therapy for infections.

Acute Disease↗

In vivo activation of human neutrophil functions by administration of recombinant human granulocyte colony-stimulating factor in patients with malignant lymphoma.

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) was administered (50 to 800 micrograms/m2) once daily as a half-hour intravenous (IV) infusion for 14 days to seven patients with malignant lymphoma. In all patients, administration of rhG-CSF not only ameliorated the decrease in absolute neutrophil count after the cytotoxic chemotherapy but also enhanced superoxide (O2-) release in neutrophils stimulated by N-formyl-methionyl-leucyl-phenylalanine (FMLP). The priming effect of rhG-CSF on neutrophil O2- release was rapid (evident within 6.5 hours) and sustained at least for 24 hours after a single IV administration of rhG-CSF. The responsiveness to further in vitro challenge of rhG-CSF was lost or reduced in neutrophils isolated after rhG-CSF treatment, indicating that neutrophils already primed in vivo by rhG-CSF are desensitized to this factor. In contrast to the results obtained with FMLP, when phorbol myristate acetate (PMA) was used as stimulus, no consistent enhancement of O2- release was observed, suggesting that rhG-CSF modulates the signal transduction pathways linked to FMLP receptors rather than increases the components of the O2- producing enzyme complexes. Administration of rhG-CSF also rapidly (evident within 15 minutes) caused an increase in expression of neutrophil C3bi-receptors that was sustained for at least 24 hours after a single IV administration of rhG-CSF. Pharmacokinetic study of rhG-CSF showed a half-life (t1/2) of 114 min. These findings show that rhG-CSF is a potent activator for neutrophil functions both in vivo and in vitro.

Aged↗

Granulocyte colony-stimulating factor in allogeneic bone marrow transplantation.

A Phase II study of recombinant granulocyte colony-stimulating factor (G-CSF) in allogeneic bone marrow transplantation (BMT) was performed. The recovery of leukocytes and neutrophils was markedly accelerated in G-CSF-administered recipients. The days to WBC count greater than 1,000/microliters (11.5 +/- 1.9) and the days to neutrophil count greater than 500/microliters (11.5 +/- 1.4) were significantly shorter than those of the monocyte-CSF (M-CSF) and CSF(-) groups. In the G-CSF group the WBC count at nadir was higher than in other groups, and neutrophil recovery preceded monocyte recovery. After the discontinuation of G-CSF, the WBC count first decreased for a few days and then increased again slowly. The short duration of leukopenia brought about a reduction in the number of febrile (greater than 38 degrees C) days which, until day 30, were 1.8 +/- 1.9 in the G-CSF group, also significantly shorter than in others. Acute graft-versus-host disease (greater than grade II) appeared in two of eight patients from the G-CSF group, this incidence being comparable to those found in the other groups. A side effect of G-CSF-mild bone pain-was observed in one patient, but it was tolerable. Six of eight patients in the G-CSF group survived for between five and 13 months after BMT with a Karnofsky score greater than 90%. No relapses were observed in the six, including one patient with chronic myelogenous leukemia and two with acute non-lymphoblastic leukemia. To determine the final influence of G-CSF on myeloid leukemia, further long-term follow-up studies are needed. G-CSF was well tolerated and seemed promising against allogeneic BMT.

Adolescent↗

[An autopsy case of adenocarcinoma of the lung with signet ring cells, manifesting with aphasia and hemiparesis due to nonbacterial thrombotic endocarditis].

A 42-year-old male was admitted to Tokyo University Hospital because of confusion, aphasia and right hemiparesis. Cranial computed tomography and cerebral angiography demonstrated cerebral infarction due to occlusion of the left middle cerebral artery, while chest roentgenography disclosed a nodular shadow in the right upper lobe and swelling of right hilar and paratracheal lymph nodes. These findings suggested carcinoma of pulmonary origin and tumor-associated cerebral thrombosis, but a possibility of gastric cancer was raised by the finding of cervical lymph node biopsy which revealed signet ring cells in metastatic adenocarcinoma. He developed disseminated intravascular coagulation syndrome and died on the 83rd hospital day. Autopsy revealed adenocarcinoma of the lung with signet ring cells and non-bacterial thrombotic endocarditis which appeared to be responsible for the cerebral infarction. The relationship between adenocarcinoma of the lung with signet ring cells and non-bacterial thrombotic endocarditis was discussed.

Adenocarcinoma↗

Atrial natriuretic peptide in human cerebrospinal fluid.

We measured immunoreactive atrial natriuretic peptide (ANP) levels in cerebrospinal fluid (CSF) collected from patients with various neurologic disorders requiring diagnostic lumbar puncture. ANP was present in all of the CSF samples from 45 patients (1.7 +/- 0.6 pmol/L, mean +/- SD). CSF ANP levels were not related to the underlying central nervous diseases of the patients, to the presence or the absence of consciousness disturbance, or to CSF osmolalities in individual patients. In 35 patients, the mean ANP concentration in CSF corresponded to 27% of that in plasma, and there was no significant correlation between ANP concentrations in each paired sample. When ANP in pooled CSF was extracted by anti-ANP-agarose and analyzed by reverse-phase high performance liquid chromatography (HPLC), multiple peaks of ANP were found. One of the major ANP peaks was identified as ANP-(103-126) on the basis of its retention time on HPLC and the specificity of the antiserum used in the radioimmunoassay; however, none of other peaks coeluted with ANP-(99-126), ANP-(101-126), ANP-(102-126), ANP-(103-125), or ANP-(105-126). We conclude from these results that ANP is present in human CSF that is differently processed from ANP in the cardiac atrium.

Adolescent↗

Binding of iodinated erythropoietin to rat bone marrow cells under normal and anemic conditions.

Specific binding sites for erythropoietin (Epo) were shown in normal and anemic rat bone marrow cells using [125I]labeled human recombinant Epo. When rats were treated once or several times with phenylhydrazine or malotilate, or by phlebotomy, the serum Epo level determined by RIA began to increase rapidly. Thereafter, both the number of erythroid colony-forming unit (CFU-E)-derived colonies and the Epo binding capacity of bone marrow cells increased almost simultaneously in response to induced anemic states, suggesting that the amount of Epo binding in bone marrow cells may reflect in vivo erythropoiesis. Scatchard analysis of the binding data from normal rats revealed the presence of a single class of binding sites (Kd = 0.18 +/- 0.04 nM, 38 +/- 5 sites/cell). In anemic states, the apparent average receptor number per cell increased (52-62 sites/cell) without changing in binding affinity toward Epo. Furthermore, [125I]Epo was cross-linked to the cell surface molecule of approximately 165 kd in nonreducing conditions and 75 kd in reducing conditions. Autoradiographic analysis indicated that Epo receptors were distributed on immature erythroid cells. Proerythroblasts were the most heavily labeled, whereas orthochromatic erythroblasts and cells of myeloid and lymphoid lineages were not labeled. Calculations based on Scatchard and autoradiographic analysis showed that proerythroblasts have 390 receptor sites per cell, twice as many as basophilic or polychromatophilic erythroblasts have. These results are consistent with the stage-specific action of Epo in physiological differentiation of erythroid cells.

Anemia↗