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K Maeda

Publications and source records attributed to K Maeda.

At least 1,081 records · Page 60Linked to original sources
PubMed1990

Effects of deoxyspergualin on collagen arthritis in mice.

We have studied the effect of the immunosuppressive agent deoxyspergualin (DSG) on collagen arthritis in mice. DSG, when given prophylactically, was capable of suppressing the development of collagen arthritis in mice as well as the immunological response to native type II collagen in a dose-dependent manner. Further, treatment of DSG, started 7 days after the primary immunization, also resulted in the inhibition of development of arthritis and immunity to collagen. The treatment of DSG, started after a booster injection, did not suppress the development of arthritis, despite suppression of antibody production in collagen. These findings suggest the possibility that a threshold level of anti-type II collagen antibodies may exist which must be exceeded before arthritis develops. Its therapeutic use in mice did not affect the clinical course of arthritis or the immune response to collagen, which is similar to the results obtained with cyclosporin.

Animals↗
PubMed1990

Molecular and functional identification and purification of complement component factor D from urine of patients with chronic renal failure.

Urine proteins of normal subject and patients with impaired renal function were analyzed by two-dimensional polyacrylamide gel electrophoresis. As a result, a clear spot was detected specifically in urine from patients with obvious renal dysfunction. The isoelectrical point of this unique spot was pH 7.1-7.2 and the flow-rate (Rf) was 0.50-0.55 as that of albumin was 1.0. Partial amino acid sequence analysis revealed that the NH2-terminal to 22nd amino acid sequence was identical with that of complement factor D. We purified 22 mg of this protein (factor D) from 5000 ml of urine from a patient on hemodialysis by three chromatographic steps using DEAE-Sephadex A-50 and Sephacryl S-200. The purified urine factor D gave a single band in sodium dodecyl sulfate polyacrylamide gel electrophoresis at the position of 23 kD, and displayed normal factor D hemolytic activity. The concentrations of factor D estimated by hemolytic assay were 1.9 micrograms/ml of normal serum, less than 0.1 microgram/ml of normal urine, 15 micrograms/ml of patient serum and 50 micrograms/ml of patient urine.

Amino Acid Sequence↗
PubMed1990

Effect of ketotifen on antigen-induced interleukin 2 (IL-2) responsiveness in lymphocytes from patients with atopic dermatitis and/or bronchial asthma.

We tested the effect of Ketotifen (4-(1-methyl-4-piperidylidene)-4H- benzo[4,5] cyclohepta[1,2-b]thiophen-10(9H)-one hydrogen (fumarate) on the induction of allergen-induced IL-2 responsiveness in lymphocytes from patients with atopic dermatitis and/or bronchial asthma. Ovalbumin (OVA)- and/or Dermatophagoides farinae(Df)-induced IL-2 responsiveness was increased in almost all patients (1-15 years old) before Ketotifen treatment. Two to 12 months administration of Ketotifen (0.06 mg/kg/day) decreased activity of the response in 7 out of 9 cases corresponding to improvement of clinical symptoms. In in-vitro studies, antigen presenting cells (adherent cells) from the patient pretreated with 5, 50 and 500 ng/ml doses of Ketotifen for 12 h failed to present OVA or Df antigen to T-cells for induction of IL-2 responsiveness. Antigen-pulsed adherent cells also failed to induce the response of the T-cells pretreated with 50 and 500 ng/ml doses of Ketotifen but not with a 5 ng/ml dose. A 50 ng/ml dose of Ketotifen did not affect T-cells for induction of the response. In contrast, the treated adherent cells are capable of presenting PPD antigen or Con A for the induced response. The combined data indicate that induction of IL-2 responsiveness of peripheral blood lymphocytes on stimulation with nominal antigen may reflect an immune response to allergen in patients with allergy and a weak immunosuppressive effect of Ketotifen seems to block the response in the pathogenic process of allergic diseases.

Adolescent↗
PubMed1990

Computerized analysis of cardiotocograms and fetal movements.

Important biological signals from the fetus, including fetal heart rate and fetal movement, were obtained electronically by recent medical engineering techniques and processed (usually) via analogue-to-digital converter followed by analysis on a personal computer. The knowledge of obstetrical experts was analysed and used in computer processing. Fetal heart rate changes were initially studied by the use of a minicomputer, programmed to provide automatic quantification of the signal and diagnosis of fetal distress. The program was memorized by programmable read only memory (PROM) and used in a clinical system. The results obtained by the system were used in many obstetrical research studies, and automatic diagnosis was used in clinical practice. An ultrasonic Doppler fetal actocardiograph was also created. The amplitude and interval of the electrical deflections produced by fetal movement were analysed. Fetal behavioural states were automatically recognized in this way. Cross-correlational analysis of fetal heart rate and fetal movement showed a close relationship between the two phenomena.

Cardiotocography↗
PubMed1990

Effect of food deprivation on the pulsatile LH release in the cycling and ovariectomized female rat.

The effect of food deprivation on the pulsatile release of LH was examined in the normal cycling and the ovariectomized (OVX) adult female rat. In the cycling animals, there were significant decreases in the mean plasma LH levels as well as the frequency and amplitude of the LH pulse 48 h after the onset of food deprivation. On the other hand, food deprivation for up to 72 h did not cause any changes in pulsatile LH release in the OVX animals. No difference in the changes in body weight and blood glucose concentration were found between the cycling and OVX rats throughout the period of food deprivation for up to 96 h. These findings suggest that ovarian factors play an important role in the early manifestation of the effect of food deprivation on pulsatile LH release and that metabolic changes as expressed by decreases in body weight and blood glucose level per se were not the direct causes in the decrease of LH release during the period of food deprivation.

Animals↗
PubMed1990

Expression and function of the transfected CD8 alpha chain in murine T cell hybridomas.

Expression and function of mouse and human CD8 (mCD8 and hCD8) alpha chain molecules in mouse T cell hybridomas were analyzed. The expression of cytolytic T lymphocyte-derived CD8 molecules was suppressed in hybridomas established by fusing the BW5147 thymoma to a CD8+ cytolytic T lymphocyte clone, while expression of CD4 remained intact in BW x CD4+ helper T cell hybridomas. However, hybridomas established by fusing a cytolytic T cell clone with BW5147 cell lines, transfected with either the mCD8 alpha or hCD8 alpha chain, expressed the T cell-derived mCD8 beta chain as a CD8 heterodimer (mCD8 alpha/mCD8 beta or hCD8 alpha/mCD8 beta). These data suggest that negative regulatory mechanisms for the mCD8 alpha gene in BW thymoma failed to suppress mCD8 beta gene expression, indicating different regulatory mechanisms for the tightly linked mCD8 alpha and mCD8 beta genes. Analysis of the antigen reactivity of the hybridomas revealed that the human CD8 alpha chain failed to increase the mouse T cell receptor - class I MHC interaction, even as a heterodimeric form with mCD8 beta molecules. However, both the human CD8 alpha homodimer and the heterodimeric form with mCD8 beta were found to be capable of suppressing the class II-restricted T cell response.

Animals↗
PubMed1990

Purification, properties, and function of flavokinase from rat intestinal mucosa.

Flavokinase (ATP:riboflavin 5'-phosphotransferase) [EC 2.7.1.26] was purified to apparent homogeneity from rat intestinal mucosa by fractionation with ammonium sulfate, gel filtration, and flavin affinity chromatography. The addition of ATP to the enzyme solution was necessary for its binding to the affinity gel. The apparent molecular weight of the enzyme was estimated to be 13,500 by gel filtration on Sephadex G-100 and by SDS-PAGE. The properties of the enzyme, including its flavin specificity, were studied. Three types of riboflavin analogues were used for the flavin specificity study; namely, ones modified at the ribityl group, and at positions 3 and 8 of the isoalloxazine ring. Of the analogues modified at the ribityl group or position 3 of the isoalloxazine ring, only 2'-deoxyriboflavin was phosphorylated and then only weakly. On the other hand, most analogues modified at position 8 of the isoalloxazine ring were good substrates for the kinase, an appropriate increase in the substituent volume at position 8 of the isoalloxazine ring resulting in an increase in the Vmax value. In a previous paper on the mechanism of intestinal absorption of riboflavin, we proposed that one of the specific processes for the absorption of riboflavin is phosphorylation by flavokinase [Kasai, S. et al. (1988) J. Nutr. Sci. Vitaminol. 34, 265-280]. The present results support this conclusion because analogues that were absorbed at low concentrations through a process specific for riboflavin in our previous study were phosphorylated effectively by the enzyme, whereas those that were absorbed solely through simple diffusion at all concentrations were not phosphorylated or only phosphorylated weakly. The properties of the flavokinases from intestinal mucosa and liver were compared.

Animals↗
PubMed1990

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Journal Article↗
PubMed1990

Melanocytic differentiation of human neuroblastoma: expression of a human melanosome-associated antigen.

Five human neuroblastoma cell lines were examined for expression of a human melanosome-associated antigen (HMSA). Only cell line SK-N-SH reacted with a monoclonal antibody, HMSA-2, shown to recognize melanosomal glycoproteins. To further characterize the melanocytic lineages of SK-N-SH, three morphologically distinct clones designated SK-N-SH-N (neuroblast type), SK-N-SH-F (fibroblast type), and SK-N-SH-EP (epithelial type) were established by colony formation cloning. By fluorescence-activated cell sorter analysis and tyrosinase assay, we found that only SK-N-SH-EP and SK-N-SH-F reacted with HMSA-2 and had tyrosinase activity. These results suggest that epithelial-type and fibroblast-type cells appear to possess the melanocytic potential, but not neuroblast-type cells. Furthermore, SK-N-SH-EP was found to spontaneously convert to neuroblast-type or fibroblast-type cells, whereas SK-N-SH-N and SK-N-SH-F clones have remained morphologically stable. Our results suggest that at least one neuroblastoma cell line, SK-N-SH, may be an excellent model for investigating clonal maturation and the melanocytic differentiation of neuroblastoma.

Antibodies, Monoclonal↗
PubMed1990

Characterization of a human melanosome-associated antigen recognized by monoclonal antibody, HMSA-2.

This study elucidates the nature of antigens recognized by monoclonal antibody (MoAb) HMSA-2, which was developed against human melanosome-associated antigen (HMSA) of malignant melanoma (Maeda and Jimbow, Cancer 59:415-423, 1987). Through flow cytometry analyses, indirect immunoprecipitation of antigen biosynthetically labeled with 35S-methionine, enzyme-linked immunosorbent assays and immunoelectron microscopy, we found that a) the antigens recognized by MoAb HMSA-2 were melanosomal matrix glycoproteins; b) these antigens were expressed mainly in the cytoplasm, although they could also be detected on the cell surface; c) the cytoplasmic expression of MoAb HMSA-2 was cell-cycle dependent; d) large amounts of these antigens were released into culture supernatants; e) MoAb HMSA-2 immunoprecipitated two major glycoproteins with molecular weights of 94 and 53 kDa from culture supernatants, and f) both components have complex N-linked oligosaccharide chains with sialic acid, suggesting that these melanosomal proteins are derived from the trans-cisternae of the Golgi. These human melanosome-associated antigens may prove useful not only for studying the immunobiology of melanogenesis, but also for the immunodiagnosis of melanocytic disorders.

Antibodies, Monoclonal↗
PubMed1990

Cutaneous T cell lymphoma differing from classical mycosis fungoides and Sézary syndrome: clinical, histological and immunohistochemical studies of six cases.

Six cases of cutaneous T cell lymphoma (CTCL), differing from classical mycosis fungoides (MF) and Sézary syndrome (SS), were studied. Initial skin eruptions were erythematoplaques, papules and tumors. Some cases showed frequent spontaneous regressions without any specific therapy; however, the prognosis was not always good. Surface phenotypes of neoplastic cells were markedly heterogeneous from the onset of initial skin eruption. Three cases expressed the T helper/inducer (Th/i) phenotype, one case had both the Th/i and T suppressor/cytotoxic phenotypes, and the other two cases lacked both surface markers. These results suggest that CTCL other than MF and SS displays marked heterogeneous clinical behavior and diverse morphological and immunophenotypical characteristics of the postthymic T cells.

Aged↗
PubMed1990

Successful bone marrow transplant and re-growth of hair in a patient with posthepatic aplastic anemia complicated by alopecia totalis.

Bone marrow transplant was performed in a child with posthepatic aplastic anemia complicated by alopecia totalis. The procedure was successful, as the graft was apparently "taken" by the recipient and hair started to grow on the head. The hair has not been lost since, and is still growing as of the date of this report. Although nonA nonB hepatitis virus was found to be the cause of hepatitis in this patient, the reason for the alopecia totalis which developed 7 years previously is unclear. The postoperative growth of the hair was attributed to restoration of normal immunologic function through bone marrow transplant.

Alopecia↗
PubMed1990

Massive fetomaternal hemorrhage: case report.

Massive fetomaternal hemorrhage (FMH) is rare. Early diagnosis is important because FMH has a poor prognosis in the antepartum or early postpartum period. A case of massive FMH in which 400 ml blood was lost is presented here. Fetal anemia was suspected from the sinusoidal fetal heart rate pattern. The hemorrhage in the maternal circulation was diagnosed before delivery by using the Kleihauer-Betke test. An emergency cesarean section was performed. The cord hemoglobin level was 3.7 g/dl. The baby's severe anemia was treated with a neonatal blood transfusion. In this case, the baby had a good clinical course. Early diagnosis and treatment of massive FMH are necessary for a good prognosis.

Adult↗
PubMed1990

Effectiveness of push/pull hemodiafiltration using large-pore membrane for shoulder joint pain in long-term dialysis patients.

Long-term hemodialysis (HD) patients complaining of shoulder joint pain were treated by HD and by push/pull HDF using high-flux synthetic membranes with large pores (Asahi PAN 20CX2) for 2 weeks. The results showed no significant difference in Kt/Vurea between HD and push/pull HDF. Nevertheless, reduction of the plasma beta 2-microglobulin was greater during push/pull HDF than during HD. These findings can be explained by far more convective flux in push/pull HDF than in HD: nearly 30 L during push/pull HDF vs. 3 L during HD. In the present study, there was no alleviation of the shoulder joint pain during HD treatment, whereas marked relief of the symptom was found during push/pull HDF treatment. Since the two treatment modalities differ simply in their efficiency in removing larger molecular weight substances, the joint pain alleviation effected by push/pull HDF could well be ascribed to elimination of an unknown larger molecular weight substance causing this symptom. However, a considerable amount of beta 2-microglobulin was removed both by HD and push/pull HDF. Therefore, the substance causing the joint pain might be larger than beta 2-microglobulin.

Female↗
PubMed1990

Suppression of bactericidal activity of human polymorphonuclear leukocytes by Bacteroides gingivalis.

The direct effects of the culture supernatant of oral microorganisms on the bactericidal activity of human polymorphonuclear leukocytes (PMNs) were investigated. The bactericidal activity of PMNs, which were preincubated with the supernatant of Bacteroides gingivalis, Bacteroides intermedius, Bacteroides melaninogenicus or phosphate-buffered saline, was examined by counting the surviving bacteria. B. gingivalis-treated PMNs were found to have a diminished ability for killing bacteria in the presence or absence of serum. The chemiluminescence response of PMNs, which were preincubated with the culture supernatant of B. gingivalis, was strikingly reduced compared with that of PMNs preincubated with phosphate-buffered saline or other bacterial culture supernatants. The production of superoxide anion (O2-) by PMNs stimulated with either formyl-methionyl-leucyl-phenylalanine or phorbol myristate acetate was reduced in both cases after the PMNs were preincubated with the culture supernatant of B. gingivalis. However, it was observed that there was more reduction in superoxide anion (O2-) production stimulated with formyl-methionyl-leucyl-phenylalanine compared with that stimulated with phorbol myristate acetate. These results suggest that B. gingivalis releases a factor which interferes with the bactericidal activity of PMNs by modulating the generation of reactive oxygen species. These suppressive effects on bactericidal activity may be important in the pathogenesis of this microorganism.

Adult↗
PubMed1990

Partial characterization of an interleukin-1-like factor in human gingival crevicular fluid from patients with chronic inflammatory periodontal disease.

A significant level of interleukin-1-(IL-1)-like activity was detected in gingival crevicular fluid obtained from sites in patients with chronic inflammatory periodontal disease, confirming a previous report of IL-1-like activity detected in human gingival crevicular fluid from patients with chronic inflammatory periodontitis (J. A. Charon, T. A. Luger, S. E. Mergenhagen, and J. J. Oppenheim, Infect. Immun. 38:1190-1195, 1982). In the present study, we sought to investigate whether this IL-1-like activity belonged to IL-1 alpha or IL-1 beta and to characterize some of the biochemical properties of this factor. Polyclonal antibodies against recombinant human IL-1 alpha or IL-1 beta (rIL-1 alpha or rIL-1 beta) have been used for serological comparison of the IL-1-like factor. IL-1-like activity was completely neutralized by anti-human rIL-1 alpha antiserum, but not by anti-human rIL-1 beta antiserum. On gel filtration with a high-pressure liquid chromatographic Superose 12 column, IL-1-like activity was separated into two peaks, one with a molecular weight of about 43,000 and the other with a molecular weight of less than 17,000. The majority of the IL-1-like factor with a low molecular weight in human gingival crevicular fluid migrated at a molecular weight of about 17,000 under the reducing conditions of sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The specificity of the IL-1-like factor was further confirmed by an immunochemical method (Western blotting [immunoblotting]) by using anti-human rIL-1 alpha monoclonal antibodies. On isoelectric chromatography with a high-pressure liquid chromatographic Mono P column, the pI of this IL-1-like factor was between pH 4.9 and 5.2. These results suggest that the IL-1-like factor in human gingival crevicular fluid from diseased sites in patients with chronic inflammatory periodontitis consists predominantly of IL-1 alpha.

Adult↗