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Biomedical subjects

T Takagi

Publications and source records attributed to T Takagi.

At least 577 records · Page 32Linked to original sources
PubMed1991

[Production of anti-33kDa protein monoclonal antibody and organ-specificity of 33kDa protein].

We produced monoclonal antibody TS-SC6 specific for 33kDa protein (33K) from bovine retina and studied the localization of 33K in mammalian retinas (rat, mouse, bovine, guinea pig and human) and pineal gland of rat. An immunohistochemical study showed that TS-SC6 reacted with the outer plexiform layer (OPL), outer nuclear layer (ONL) and rod inner segments (IS) in rat, ONL, IS and IS in mouse and guinea pig. It reacted with ONL and rod outer segments (OS) in bovine, ONL and OS in human. Immunoreactivity was seen in the pineal gland, but there was no immunoreactivity in the central nervous system surrounding the pineal gland. Immunoblot analysis was carried out with soluble fractions prepared from the retina, pineal gland, cerebrum, liver, kidney and intestine of rats. TS-SC6 reacted with 33K of the retina and pineal gland, respectively. However, it did not react with soluble fractions from the other tissues.

Aged↗
PubMed1991

[New method for estimating left ventricular myocardial elasticity by vibration analysis].

We solved numerical solutions of Advani-Lee's equation, which treats free vibrations of fluid-filled spherical shells, and forms the basis for non-invasive estimation of left ventricular myocardial elasticity. Numerical results showed that elasticity is approximated by E = 86.5.a2.f2 (E: elasticity (dyn/cm2), a: internal radius (cm), f: eigen-frequency (Hz)). To examine the accuracy of this theoretical equation in estimating elasticity, we made 7 spherical shells of silicone rubber, and compared the estimated elasticity by this equation with that by a standard stretch test. The elasticity calculated by Advani-Lee's equation and by stretch test proved to be nearly identical. Therefore, we concluded that we can estimate the elasticity of a spherical shell using this equation. We calculated the myocardial elasticity at the first heart sound emission in 25 normal persons with a simplified (approximated form of) Advani-Lee's equation. The mean elasticity in normal subjects was (7.04 +/- 2.46) x 10(5) dyn/cm2.

Elasticity↗
PubMed1991

Formation and degradation of basement membrane collagen.

Serum levels of type IV collagen and hepatic type IV collagenase activity, as markers for formation and degradation respectively of basement membrane collagen (type IV collagen) in liver, were measured in patients with various alcoholic liver diseases. Development of alcoholic liver fibrosis seems to be due to both increased formation and decreased degradation of basement membrane collagen. Both measurements of type IV collagenase activity and serum level of type IV collagen were assumed to be useful to predict irreversible state of hepatic fibrosis.

Basement Membrane↗
PubMed1991

[Gene-transfer into bone marrow cells].

We have intended to improve gene-transfer technique into hematopoietic stem cells for somatic gene therapy. 1) We have developed a new packaging cell line, ampGPE for retroviral production. LTR-less gag, pol or env genes from Moloney murine leukemia virus were separately inserted into BMGNeo vector. Packaging cell lines containing 20-50 copies of these two kinds of plasmid were obtained. Retrovirus stock for gene-transfer have been produced at a high titer (10(5)-10(6) cfu/ml) and without replication-competent viruses by using ampGPE. 2) Retrovirus-transduced murine CFU-GM have been found to selectively proliferate (5-10 fold/week) in liquid capture with recombinant murine IL-3, human IL-6 and G418 to consequently obtain enough amount of, highly concentrated (70-100%), and gene-transferred murine CFU-GM for gene-delivery system.

Animals↗
PubMed1991

The role of endogenous gonadotropin release in the etiology of ovarian enlargement during purified urinary follicle-stimulating hormone therapy.

Patients with polycystic ovarian disease were grouped into three groups according to their maximum ovarian diameter (maxD) after ovulation induction by purified urinary follicle-stimulating hormone (FSH). Serum luteinizing hormone (LH) and FSH were measured daily by radioimmunoassay and size and number of follicles were assessed by ultrasonography. Follicle-stimulating hormone in group A (80 mm less than or equal to maxD) was significantly higher than those of group B (60 mm less than or equal to maxD less than 80 mm) and C (maxD less than 60 mm) for the last 4 days of the treatment. This FSH rise in group A was not accounted for by FSH accumulation by the study of pharmacodynamics, and so was thought to be of endogenous origin. Luteinizing hormone was also elevated 3 days before the administration of human chorionic gonadotropin (hCG) in both groups A and B. The number of follicles in group A at hCG administration was significantly greater than that of group C. Any significant differences were not found in either total amount of purified urinary FSH or in the basal FSH and the LH levels before treatment of the three groups. These results suggest that excessive ovarian enlargement during gonadotropin therapy is caused by multiple follicular development primarily stimulated by endogenous FSH. Endogenous LH release further enhances ovarian enlargement.

Chorionic Gonadotropin↗
PubMed1991

[Prenatal evaluation of the platelet counts in the fetuses and the neonates of the mothers complicated with idiopathic thrombocytopenic purpura].

We investigated 25 pregnancies with ITP. The results were as follows. 1. The platelet counts of the maternal blood just before delivery were not correlated with those of the cord blood. 2. It was suggested that the maternal PAIgG value just before delivery could foretell the onset of neonatal thrombocytopenic purpura. 3. The platelet counts in fetal scalp blood were correlated with those of the cord blood, but falsely lower platelet counts were found in the fetal scalp samples. 4. We saw 5 cases of percutaneous umbilical blood sampling (PUBS) in pregnancies with ITP. PUBS was found to be a useful and safe method. The indications for PUBS and fetal platelet transfusion in pregnancy with ITP are discussed.

Cesarean Section↗
PubMed1991

[In vitro effect of combined use of BH-AC and nitrosourea derivatives against adriamycin-resistant human leukemia cell line].

Cytocidal effects of combined use of BH-AC and nitrosourea derivatives (MCNU, and ACNU) were evaluated in vitro against adriamycin-resistant human leukemia cell line (K-562/ADR-I). K-562/ADR-I cells were resistant to six kinds of agents (vindesine, mitoxantrone, aclacinomycin, cisplatin, MCNU, and BH-AC) of 14 agents tested and this cell line proved to be a multi-drug resistant line. Combined use of BH-AC and MCNU did not achieve additive effects on K-562, parent cell line and BH-AC and MCNU were less effective to K-562/ADR-I by single use. However, combination of BH-AC and MCNU showed additive effects. These results supported the evidence that combination of BH-AC with MCNU was effective in patients with multi-drug resistant malignant lymphomas.

Antineoplastic Agents↗
PubMed1991

[Clinical application of thymidine kinase activity in patients with acute non-lymphocytic leukemia].

An improved method for the detection of thymidine kinase (TK) activity with the use of 125I-iododeoxyuridine as the substrate. Radioimmunoassay of prolifigen TK "Daiichi", was used for this assay. Eighty-seven serum samples were collected from 40 patients with acute nonlymphocytic leukemia in four institutions. The levels of TK were measured in the time of pretreatment, remission, and recurrence, and the relationship between the levels of TK and either LDH, marrow blasts, or circulating blasts was also examined. The levels of TK were significantly lower in the state of remission than in the pretreatment. However, the level of TK in remission was much elevated in the majority of cases than normal range (less than or equal to 5 units/l). On the contrary, LDH in remission was within normal limits in the majority of cases. The level of TK in the state of relapse was significantly higher than in the remission. The level of TK correlated in some extent with the percentage of marrow blasts (r = 0.508), and the level of TK in more than 5% of marrow blast was most beyond normal range. Correlation coefficient between the percentage of circulating blasts and TK (r = 0.577) was slightly higher than that between the percentage of marrow blasts and TK. Correlation coefficient between the level of TK and the number of marrow blasts was higher than that between LDH and number of marrow blasts. The levels of TK correlated well with serum LDH (r = 0.778), and was more sensitive than LDH. In conclusion, it was suggested that TK could be used as one of an useful and supplemental tumor marker in the follow-up of treatment of acute nonlymphocytic leukemia and to monitor the effect of therapy.

Biomarkers, Tumor↗
PubMed1991

Muscle tissue reactions to implantation of bone matrix gelatin.

Histologic changes of muscle tissue in the early stage of heterotopic osteogenesis induced by syngeneic insoluble bone matrix gelatin (BMG) with bone morphogenetic protein in rats was observed by light and electron microscopy. BMG induced cartilage in muscle tissue by Day 7 after its implantation, woven bone by Day 10, and lamellar bone with bone marrow by Day 14. The new findings in this work include (1) the disappearance of the basement membrane of muscle fibers; (2) the activation of the satellite cells of muscle fibers; (3) the appearance of fibroblastlike cells that closely resembled activated satellite cells among the degenerated muscle fibers or on the surface of the BMG; and (4) the change of fibroblastlike cells to chondroblasts or osteoblasts. These findings suggest that intramuscular implantation of BMG caused the conspicuous disappearance of the basement membrane of the muscle fiber and may play a part in osteogenesis induced by BMG.

Animals↗
PubMed1991

[Parameter in fulminant hepatitis].

Serum complement hemolytic activities (CH 50) and plasma prothrombin time (PTT) of patients with fulminant hepatitis (FH, 11 cases of acute type and 11 cases of subacute type), severe acute hepatitis (AH-S, 9 cases) and typical acute hepatitis (AH-T, 20 cases) were examined. AH-S was diagnosed as AH patients with PTT under 40% and without hepatic coma. Survival rates were 100% in AH-S, 45.5% (5/11) in acute type of FH and 9.1% (1/11) in subacute type of FH. The mean levels of CH 50 on their admission were 42.6 U/ml in AH-T, 28.8 U/ml in AH-S and 13.1 U/ml in FH. CH50 levels in acute hepatitis decreased in parallel to the severity of the disease and correlated with PTT (r = 0.809). In many cases of FH and almost all cases of AH-S, CH50 levels changed more slowly than those of PTT. The patients with AH-S and subacute type of FH showed a prolonged PTT and the normal levels of CH 50 in their acute phase. These results indicate that CH50 and PTT could be useful markers differentiating subacute type from acute type of fulminant hepatitis.

Acute Disease↗
PubMed1991

[Similar efficacy of less than 6 and 7-10 courses of therapy with anthracycline-based combination chemotherapy for localized non-Hodgkin's lymphoma of extranodal type].

We studied retrospectively the influence on the prognosis of patients with localized non-Hodgkin's lymphoma of extranodal type with regard to the duration of an anthracycline-based combination chemotherapy-modified CHOP regimen. The patients who were given at least 2 courses of chemotherapy and attained complete remission were selected. These were subdivided into two groups; one for patients who were given 2-6 courses, the other for patients given 7-10 courses. The relapse-free survival curve for patients treated with 7-10 courses was slightly better than that of the patients treated with less than 6 courses. However, the difference between them was not significant. From the results, it was considered possible to reduce the chemotherapy from 10 to 6 courses in patients with localized non-Hodgkin's lymphoma of extranodal type. A prospective randomized study is now in progress at Saitama Cancer Center.

Adult↗
PubMed1991

Molecular cloning of the L-phenylalanine transaminase gene from Paracoccus denitrificans in Escherichia coli K-12.

The L-phenylalanine transaminase gene of Paracoccus denitrificans was cloned by a shotgun method using the Escherichia coli K-12 mutant DG30, which lacks three distinct transaminase genes. Plasmid pPAP142 was constructed by inserting a 2.2-kb fragment carrying the transaminase gene into pUC18. Strain E. coli K-12 HB101 cells harboring the plasmid produced 20-fold to 30-fold more transaminase than wild type P. denitrificans cells. The nucleotide sequence of the 2.2-kb fragment was determined, revealing that the deduced amino acid sequence of the transaminase of P. denitrificans is similar to that of other transaminases.

Amino Acid Sequence↗
PubMed1991

Subperiosteal implantation of bone morphogenetic protein adsorbed to hydroxyapatite.

Bone development was induced by bone morphogenetic protein (BMP) adsorbed to hydroxyapatite (HAP) under the periosteum of rat parietal bone. The BMP was isolated by Sephacryl-S200 column chromatography after passage through a membrane filter system. The yield of the fraction with BMP activity was 20 times greater than yields obtained by conventional methods. BMP was adsorbed to HAP in vacuo. HAP alone was implanted as a control. The formation of cartilage and bone was observed seven days after the implantation of BMP-HAP, and the newly formed bone fused with the host calvaria after 28 days. In control rats, no bone formation was seen within 56 days after implantation. The BMP-HAP complex was more effective in induced periosteal bone formation than HAP only.

Adsorption↗
PubMed1990

Primary structure of the target of calcium vector protein of amphioxus.

CaVPT, a target protein of Ca2(+)-vector from amphioxus muscle, was purified from its complex with CaVP after dissociation by 6 M urea and chromatographies on DEAE-cellulose and calmodulin-Sepharose. The amino acid sequence of CaVPT has been determined. The protein is composed of 243 residues and possesses an unblocked N terminus. Its molecular weight is 26,621, distinctly lower than the apparent molecular weight deduced from electrophoresis on sodium dodecyl sulfate-containing gels. CaVPT contains a potential Asn-linked glycosylation site, four potential protein kinase C phosphorylation sites, and two casein kinase II phosphorylation sites. From the sequence the following three particular domains can be inferred: a collagen-like N-terminal segment, rich in Pro and Ala, that resembles the N-terminal segment of skeletal muscle myosin light chain kinase; next to it (from residues 33 to 50) is located a strongly amphiphilic and basic alpha-helical segment which likely binds the calcium vector protein since a proteolytic cut after Arg50, occurring occasionally during the purification of CaVPT, impairs the binding to immobilized calmodulin. This segment is followed by two immunoglobulin folds. The two immunoglobulin folds typically belong to the C2 subclass and particularly resemble those present in the neural cell surface adhesion molecules NCAM, L1, F11, MAG, TAG-1, fasciclin II, and amalgam. Recently, the presence of immunoglobulin folds of this type has been reported in some intracellular muscular proteins, namely in smooth muscle myosin light chain kinase, striated muscle C protein and titin, as well as in the nematode 600-kDa protein twitchin. From this structural study we can formulate the working hypothesis that CaVPT acts on the structure of the thick filament in muscle or regulates, perhaps via other immunoglobulin fold-containing proteins.

Amino Acid Sequence↗
PubMed1990

Monomer-dimer structure of cytochrome-c oxidase and cytochrome bc1 complex from the thermophilic bacterium PS3.

Molecular weights of three membrane proteins have been measured in the presence of 0.1% octaethylene glycol n-dodecyl ether (C12E8) by the measuring system in which a membrane protein eluted from a gel chromatography column is monitored sequentially for ultraviolet absorption, light scattering and refractive index. The relative molecular mass (Mr) and amount of bound detergent per protein (delta) can be calculated from these data, if instrumental constants are measured using a set of appropriate water-soluble proteins which does not bind nonionic surfactants. The molecular masses of cytochrome c oxidase and cytochrome bc1 complex from the thermophilic bacterium PS3 were determined to be 127 kDa and 185 kDa, respectively, indicating that the oxidase is monomeric, while the bc1 complex dimeric in the presence of C12E8. The larger apparent molecular mass of about 310 kDa of the PS3 oxidase obtained from the retention time of the gel chromatography (Sone, N., Sekimachi, M. and Kutoh, E. (1987) J. Biol. Chem. 262, 15386-15391) turned out to be due to a high binding ability with the detergent (delta = 1.25 g/g) of this very hydrophobic protein. Analyses of bovine heart cytochrome oxidase, on which monomer/dimer properties have been reported, showed that the enzyme is mainly dimeric (Mr = 374,000), while a small portion is monomeric (Mr = 191,000). Mild alkaline treatment of this enzyme caused monomerization of the enzyme with accompanying aggregate formation. These results, thus, show that this method is suitable to analyze monomer/dimer conversion of membrane protein as well as to estimate structure of membrane proteins.

Animals↗