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M Umeda

Publications and source records attributed to M Umeda.

At least 415 records · Page 23Linked to original sources

[Comparison of urinary and seminal N-acetyl-beta-glucosaminidase isoenzymes].

N-acetyl-beta-glucosaminidase (NAG) and its isoenzymes were measured in the urine and seminal plasma of healthy volunteers. Urinary NAG level was 2.62 +/- 1.30 U/L (mean +/- standard deviation), 1.99 +/- 0.77 U/g creatinine and seminal NAG level was 2370 +/- 1007 U/l. Urinary NAG level was 2.59 +/- 1.44 U/l, 1.93 +/- 0.80 U/g creatinine in males and 2.67 +/- 1.15 U/l, 2.08 +/- 0.78 U/g creatinine in females, and there was no significant sex difference. NAG isoenzymes in the urine and seminal plasma were divided into two major peaks, A and B. The A:B ratio was 78.0 +/- 6.5: 21.9 +/- 6.5 in the urine and 24.7 +/- 3.2: 75.2 +/- 3.2 in the seminal plasma, and was significantly different. Urinary NAG isoenzyme was 80.3 +/- 6.7: 19.6 +/- 6.7 in males and 74.1 +/- 4.3: 25.9 +/- 4.3 in females, and there was no significant difference between the sexes. These results indicated that urinary and seminal NAG can be differentiated by measuring the isoenzymes. Furthermore, the comparison of seminal NAG isoenzymes before and after vasectomy indicated that seminal NAG may be affected not only by the sperm but also by the prostatic fluid.

Acetylglucosaminidase↗

New abnormalities in the morphology, cell surface receptors, and electrolyte metabolism of In(Lu) erythrocytes.

The In(Lu) phenotype is inherited as an autosomal dominant trait and is characterized by suppression of the Lutheran, P1, i, and Aua erythrocyte blood group antigens. We have developed a monoclonal antibody (L21) that strongly agglutinates all erythrocytes except In(Lu), and we have identified eight In(Lu) individuals among 42,000 blood donors tested. Studies of two families confirmed the dominant mode of inheritance and revealed several new features of this phenotype. The erythrocytes of all five affected individuals from the two families exhibited diminished hemagglutination by the lectin concanavalin A, although they reacted normally with several other lectins. The erythrocytes of two affected individuals in one family exhibited marked acanthocytosis. The erythrocytes of the proposita of the other family exhibited a mild degree of poikilocytosis, but the cells of the other two affected individuals in this family had normal morphology. The osmotic fragility of fresh In(Lu) erythrocytes was normal, but after incubation for 24 hours at 37 degrees C in plasma the In(Lu) cells exhibited a marked increase in resistance to osmotic lysis. During the incubation period the erythrocytes lost K+ and their total cation content was diminished. These data indicate that in addition to the suppression of blood group antigens noted previously, the In(Lu) phenotype includes a variety of morphological abnormalities and a defect in electrolyte metabolism. The use of L21 and similar monoclonal antibodies provides a more sensitive means of detecting In(Lu) erythrocytes than typing with human anti-Lub antisera.

Antibodies, Monoclonal↗

Liposome immune lysis assay (LILA). Application of sandwich method to determine a serum protein component with antibody-bearing liposomes.

A complement-dependent liposome immune lysis assay (LILA) using carboxyfluorescein (CF)-entrapped liposomes bearing antibody was developed to measure C-reactive protein (CRP) antigen as a model of protein antigens in human sera. Goat anti-CRP antibody was covalently coupled to liposomes, and a specific lysis of the liposomes could be observed when the liposomes were incubated with both rabbit anti-CRP antibody (secondary antibody) and CRP antigen in sera in the presence of guinea pig complement. In this assay system, so-called sandwich assay, CRP (a multivalent antigen) bound to the liposomes bearing anti-CRP antibody and subsequently secondary antibody, which activated complement efficiently. The amount of CF released by a complement-dependent liposome immune lysis was proportional to CRP concentrations. This sandwich assay was simple, fast, highly sensitive, and covered the ranges 10-300 ng of CRP/ml in a homogeneous mode, that is, one where no separation step was employed. The results correlated well with those obtained by single radial immunodiffusion and enzyme immunoassay. This assay system would be applicable to the measurement of other protein antigens.

Antibodies↗

The occurrence of anti-3-fucosyllactosamine antibodies and their cross-reactive idiotopes in preimmune and immune mouse sera.

The carbohydrate determinant 3-fucosyllactosamine (3-FL), Gal(beta 1-4)[Fuc alpha 1-3]GlcNAc-R, which is also known as SSEA-1 or as the X determinant, is very immunogenic in BALB/c mice. Many monoclonal antibodies directed against this structure have been obtained by immunization of mice with murine teratocarcinomas and human carcinomas and myeloid cells. We have undertaken an analysis of the regulation of these antibodies and of their idiotypic, structural, and genetic diversity. We have described previously the preparation of syngeneic monoclonal anti-idiotypic antibodies (6C4 and 6B1) that reacted with 50% of a panel of monoclonal anti-3-FL antibodies. In this study, we have examined the occurrence of anti-3-FL antibodies and their cross-reactive idiotopes in the sera of unimmunized and immunized mice. All BALB/c sera examined had more naturally occurring antibodies against 3-FL than against four other glycolipid antigens, and the 6C4 and 6B1 idiotopes were also detected in these sera. Approximately 25% of the anti-3-FL antibodies could be removed from a pool of BALB/c sera by a 6C4 affinity column, and the eluate from this column exhibited strong binding to 3-FL antigens. After a single i.v. injection of a 3-FL-positive glycolipid coated on Salmonella minnesota, anti-3-FL titers rose in BALB/c mice. The level of 6B1 idiotope rose in most mice, but the idiotope level showed no correlation with anti-3-FL titers. Naturally occurring antibodies against 3-FL were also noted in the sera of AKR, C3H/He, DBA/2, BALB/c-nu/nu, and CBA/CaHN mice but not in C57BL/6, SM, or CBA/N mice. A single i.v. injection of antigen elicited an antibody response in C3H/He mice but not in C57BL/6, SM, or DBA/2 mice. These data indicate that several strains of mice have more naturally occurring IgM antibodies against the 3-FL structure than against other glycolipids, and that this response may be genetically regulated. The 6C4 and 6B1 cross-reactive idiotopes that we have identified previously on monoclonal antibodies are also present in preimmune and immune sera. The existence of a population of B lymphocytes that are primed against the 3-FL determinant accounts in part for the immunogenicity of this structure.

Animals↗

Idiotypic determinants of monoclonal antibodies that bind to 3-fucosyllactosamine.

Many monoclonal antibodies that react with the lacto-N-fucopentaose III (LNF III) antigenic determinant, Gal beta 1-4(Fuc alpha 1-3)GlcNAc beta 1-3Gal beta 1-4Glc, have been described recently. The terminal trisaccharide of this determinant, fucosyllactosamine, is present on glycolipids and glycoproteins and on the surface of granulocytes, monocytes, and other cells. To study the structural and genetic diversity of these antibodies, syngeneic anti-idiotypic monoclonal antibodies were produced in BALB/c mice against PMN 6, a monoclonal antibody directed against this sequence. Anti-idiotypic antibodies 6B1 and 6C4 reacted with 50% of a panel of 20 anti-LNF III monoclonal antibodies, whereas 6A3 reacted strongly only with PMN 6. This indicates that the determinants recognized by 6C4 and 6B1 represent major cross-reactive idiotopes of this family of antibodies. The binding of idiotypic antibodies to a glycolipid bearing this antigenic determinant was completely inhibited by the three anti-idiotypic antibodies, 6A3, 6B1, and 6C4. The idiotopes could be demonstrated on the heavy chain of the monoclonal antibodies by an antibody transfer technique when mild reducing conditions were employed, but a high concentration of reducing agent destroyed the idiotypic determinants. This suggests that the anti-idiotypic antibodies recognize conformational structures expressed on the heavy chain molecules. The binding of 18 monoclonal antibodies to two glycolipid antigens and to a fucosyllactosamine-bovine serum albumin conjugate was compared. Antibodies that possessed the 6C4 cross-reactive idiotope bound to fucosyllactosamine-bovine serum albumin more weakly than idiotype-negative antibodies (p = 0.001). This suggests that the 6C4-positive antibodies might represent germline structures.

Animals↗

Rhythmic change of myocardial phosphate metabolite content in cardiac cycle observed by depth-selected and EKG-gated in vivo 31P-NMR spectroscopy in a whole animal.

The newly developed pulse width modulation method for the depth-selected in vivo NMR under high magnetic field (6.4 Tesla), sectional magnetic resonance (SMR), enabled us to selectively obtain and follow time sequence of P metabolism of rat heart in a whole body. An EKG-gated 31P-SMR spectroscopy at every 30 m sec, after the R wave, with calibrating the resonance intensity by an external standard, demonstrated a synchronous oscillation of both contents of creatine phosphate (CP) and beta-ATP: minimal at the early 2/3 of the systole as was identified by the aortic pressure measurement and maximal at the last 1/3 of the diastole, while inorganic phosphate content varied antiphasically to CP or ATP without obvious change of intracellular pH in cardiac cycle. This is the first report that described an in vivo detection of cyclic change of phosphate metabolites in the heart.

Adenosine Triphosphate↗

Inhibition of biological actions of 12-O-tetradecanoylphorbol-13-acetate by inhibitors of protein kinase C.

Evidence has been accumulated that the phorbol ester receptor in intact cells is protein kinase C. However, it is not certain whether the various actions of 12-O-tetradecanoylphorbol-13-acetate (TPA) on cultured cells are all mediated by the activation of protein kinase C. Therefore, we examined the effects of inhibitors of protein kinase C, palmitoylcarnitine (PC) and phloretin (PH), on several actions of TPA on cells. PC at the concentration of 30 micrograms/ml completely prevented the inhibitory actions of TPA on differentiation of Friend leukemic cells (FLC) induced by hexamethylene bisacetamide (HMBA) and on metabolic cooperation of V79 cells. PC, however, did not prevent the TPA-induced promotion of the transformation of BALB/3T3 cells, even at the concentration of 40 micrograms/ml. On the other hand, PH at the concentration of 30 micrograms/ml did not inhibit the actions of TPA to inhibit differentiation of FLC and metabolic cooperation of V79 cells, but completely inhibited the transformation of BALB/3T3 cells and its promotion by TPA. These results indicate that protein kinase C possibly mediates some of the actions of TPA, such as the inhibition of differentiation and metabolic cooperation, but not that of the promotion of in vitro transformation.

Animals↗

Cellular mechanisms of transformation of BALB/3T3 A31-1-1 cells [corrected] by gamma-irradiation.

In order to clarify the mechanism of transformation, the effect of cell generation number on the time of appearance of transformed cells was examined in gamma-ray-irradiated BALB/3T3 A31-1-1 cells. The results showed that an increased number of cell generations (produced by seeding of cells at lower cell densities as well as under dispersed conditions) was important for increasing the rate of transformation. By a procedure in which irradiated cells in dishes were dispersed by trypsinization and recultured in the original dishes after cultivation for a certain number of days, we expected to establish the so-called "expression period." The rationale was that the number of transformed foci would increase after the appearance of a transformed cell due to its expansion. The expression period was shown to be 1.5 weeks on average. The time of appearance of transformed cells, however, varied from as early as about 1 week to 2.5 weeks. When cells were seeded at higher or lower cell densities and examined by the technique of dispersion and reculture, the expression periods were almost the same. Thus, it is probable that transformed cells can appear before or after the confluent state is reached.

Animals↗

High level of beta-type transforming growth factor activity in human urine obtained from cancer patients.

Activity of transforming growth factor (TGF) in urine was examined by the use of cloned BALB/3T3 A31-1-1 indicator cells. When urine was extracted by an acid-ethanol method, fractionated on a Bio-Gel P-100 column, and analyzed for TGF activity, samples from healthy persons showed no activity, but 80% of the samples from advanced cancer patients had the activity. Activity observed in tumor-bearing patients was eliminated after therapy. Further analysis was carried out in a much simpler way by the fractionation of urine samples after only dialysis and lyophilization. An extensive survey of TGF activity in urine using BALB/3T3 indicator cells revealed weak or intermediate (19%) activity in healthy persons and high (56%) or intermediate (31%) activity in advanced cancer patients. When urine samples were analyzed and compared using both BALB/3T3 cells and NRK 49F cells, the BALB/3T3 cells were shown to form colonies in response to beta-type TGF but not to alpha-type TGF. The present results are the first demonstration of an elevated level of beta-type TGF in urine from cancer patients.

Biological Assay↗

[A phase II study of epirubicin in acute leukemia: a cooperative group study].

A new doxorubicin analogue, epirubicin (EPI), has been evaluated in 11 institutions throughout Japan in a phase II study in patients with acute leukemia. A total of 41 patients were entered into this study between January 1983 and July 1985, and 34 were considered evaluable. Two patients were added for evaluation of toxicity. There were 25 males and 9 females with a median age of 43 years. Of the 34 evaluable patients, 24 had previously been treated with intensive combination chemotherapy, 21 with anthracyclines. The remaining ten were previously untreated patients. Underlying diseases were acute lymphocytic leukemia (ALL) in 15, acute non-lymphocytic leukemia (ANLL) in 17 and blastic crisis of chronic myelogenous leukemia (CML/BC) in 2. EPI was administered intravenously in two schedules, a high-dose regimen consisting of 24 to 60 mg/m2/day for 3 to 5 days and a low-dose regimen involving 11-17 mg/m2/day for 5 to 8 days. Responses were obtained in 5 (33.3%) of 15 patients with ALL, 3 of these attaining complete remission, 2 (11.8%) of 17 patients with ANLL and one (50.0%) of 2 patients with CML/BC. Out of the 21 patients who had received previous anthracyclines, 4 (19.1%) attained responses. Also, responses were obtained in 23.5% with the higher doses as well as 24% with the lower doses. The remission duration of responders was 1, 1, 3, 3, 3, 16+, 17 and 26 weeks, respectively. The major non-hematologic toxicity was stomatitis which occurred in 15 patients, in 11 of whom the symptoms were severe (Grade 3 or 4). This stomatitis was thought to be the dose limiting factor. On the basis of the above observations, we concluded that EPI was active against acute leukemia, especially ALL. Stomatitis was considered to be the dose-limiting factor, especially in the high-dose regimen. Toxicity was tolerable in the low-dose regimen.

Acute Disease↗

Homogeneous determination of C-reactive protein in serum using liposome immune lysis assay (LILA).

Recently, we have developed an analytical system based on a complement dependent liposome immune lysis assay (LILA) to measure antibody against protein antigens. This paper describes the application of LILA to measure protein antigens by inhibition reaction. We choose human C-reactive protein (CRP), one of acute phase reactants, for a model of antigen determination. CRP antigen is coupled to the carboxyfluorescein entrapped multilamellar liposomes by using N-hydroxysuccinimidyl 3-(2-pyridyldithio) propionate and dithiothreitol, and a specific lysis of liposomes is achieved upon the addition of anti-CRP antibody in the presence of complement. Inhibition of this assay can be observed by the addition of competing amounts of CRP in human serum. This inhibition assay is simple, fast, highly sensitive, reproducible and homogeneous. The assay covers the ranges 10-500 micrograms/l. In an experiment using 50 samples, the results by LILA correlated well with those by single radial immunodiffusion and enzyme immunoassay (correlation coefficient: 0.99 and 0.93, respectively).

Antigens↗