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Biomedical subjects

M Toyoda

Publications and source records attributed to M Toyoda.

At least 19 recordsLinked to original sources
PubMed1995

[Detection of chromosomal aberration using fluorescence in situ hybridization on breast cancer].

The relationship between interphase cytogenetics and prognostic factors, especially the grade of nuclear atypism, nuclear DNA content, histological lymph node metastasis and clinical data was examined in 48 primary breast cancer specimens (touch preparation). Using fluorescence in situ hybridization (FISH) with a chromosome-specific DNA probe, the copy number of pericentrometric sequences on chromosome 17 was examined within the interphase nuclei in touch preparations from the tumor. The copy number of chromosome 17 was correlated with the increase in the grade of nuclear atypism, tumor size, histological lymph node metastasis and nuclear DNA content. In the diploid type of nuclear DNA content, the copy number of chromosome 17 was correlated with the increase in the grade of nuclear atypism and histological lymph node metastasis. In conclusion, the numerical chromosomal aberrations detected by FISH were found in the DNA diploid cases by FCM. The detection of numerical chromosomal aberrations by FISH provide important information about the prognostic factors.

Breast Neoplasms↗
PubMed1994

Determination of tomatine in foods by liquid chromatography after derivatization.

A liquid chromatographic method for measuring tomatine levels in tomatoes and tomato products was developed. Tomatine was extracted with 1% acetic acid and purified on a C18 cartridge. Tomatine in the eluate was acetylated with acetic anhydride and isolated on a C18 cartridge. The solvent in the eluate was evaporated and the residue was dissolved in acetonitrile. An aliquot was injected into an Inertsil ODS-2 HPLC column and the acetylated tomatine was measured at 205 nm using a UV detector. The limit of determination was 1 microgram g-1. Tomatine was detected in the green portions of tomatoes and in tomato ketchups and juices at levels below 7 micrograms g-1.

Acetylation↗
PubMed1994

Modulation of immunoglobulin production and cytokine mRNA expression in peripheral blood mononuclear cells by intravenous immunoglobulin.

Intravenous immunoglobulin (IVIG) has the potential to regulate Ig production, but the mechanism(s) responsible for this effect is unknown. In experiments reported here, we examined the ability of IVIG to regulate Ig production in human peripheral blood mononuclear cells (PBMCs) stimulated with pokeweed mitogen (PWM). IVIG (2-10 mg/ml) showed a potent (80-85%) inhibition of PWM-stimulated IgG, IgM, and IgA production. To determine more precisely how IVIG mediated the inhibition of Ig production, we studied Ig promoting cytokine gene expression after PWM stimulation with or without IVIG (2 and 10 mg/ml) using dot-blot techniques. RNA was isolated from PBMCs at predetermined time points and probed with cDNAs specific for human cytokines (IL-1 beta, IL-2, IL-2R, IL-4, IL-5, IL-6, gamma-IFN, and TNF-alpha). IL-6 mRNA accumulation was maximal at 4.5 hr post-PWM stimulation and was inhibited 64-75% when IVIG (10 mg/ml) was present. gamma-IFN mRNA levels peaked at 72 hr poststimulation and were also 68-75% inhibited by IVIG. IL-2 mRNA levels peaked at 4.5 hr and were 23-46% inhibited by IVIG. The inhibitory effect of IVIG on production of these cytokines (IL-6 and gamma-IFN) was also observed at the protein level in sonicated PBMCs after incubation with PWM and IVIG. The mRNA levels for other cytokines were not or only minimally inhibited by IVIG. Addition of IL-6, gamma-IFN, or IL-2 partially restored Ig production in IVIG-treated PWM-stimulated cultures, suggesting that inhibition of other cytokines or another mechanism(s) independent of cytokine inhibition might also be involved, although inhibition of IL-6, gamma-IFN, and IL-2 may be one of the critical factors in the suppression of Ig production by IVIG.

Cells, Cultured↗
PubMed1994

Pathogenesis in pili torti: morphological study.

To clarify the mechanism of pili torti formation, hair materials obtained from a patient with the typical classical type of pili torti were examined. Light microscopy, scanning electron microscopy (SEM), transmission electron microscopy, (TEM) and 3-D analysis revealed that: (1) The hair shaft was partly flattened. The hairs twisted clockwise or counter-clockwise on their own axis and some hairs were knotted. (2) Short hairs showed disruptions at the flattened or unflattened regions, at the knot, or at the root of branched hairs caused by longitudinal ruptures. (3) Light microscopically, cell vacuolation and irregularity in thickness of the outer root sheath (ORS) at the suprabulbar level were seen. At the middle to upper levels of the follicles, some eosinophilic pyknotic ORS cells were observed scattered around. (4) At the upper levels, the ORS and inner root sheath (IRS) partly revealed irregularity of thickness and formed an irregular-shaped hair canal. (5) By DACM staining, cytoplasmic SH fluorescence showed an irregular arrangement of the ORS cells. Some abnormal SH- or SS-positive cells were observed scattered throughout the ORS. (6) Ultrastructurally, the irregularities in thickness and cell shape of the IRS and ORS became visible at the level, where the Henle's layer keratinized. In the hair cortex, there was no abnormality of nuclei and the keratin fibers were normally produced, although fibers were partially wavy. (7) By 3-D analysis, hair twist was already seen at the middle level of the hair follicles.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Effect of alpha-linolenic acid on the metabolism of omega-3 and omega-6 polyunsaturated fatty acids and histamine release in RBL-2H3 cells.

We examined the effect of alpha-linolenic acid (18:3 (n-3)) pretreatment on the metabolism of omega-3 and omega-6 polyunsaturated fatty acids and histamine content and release of RBL-2H3 cells. RBL-2H3 cells grew without reduction in number when incubated with subculture media for 3 d and then placed again in serum-free medium with bovine serum albumin (BSA) and epidermal growth factor (EGF). Cholesterol pullulan (10 micrograms/ml) emulsified alpha-linolenic acid (20 micrograms/ml) was recommended as an additional form serum free medium. We determined the fatty acid composition in all neutral lipids, free fatty acids and all phospholipids in alpha-linolenic acid-treated cells. In all cases the concentration of alpha-linolenic acid and docosahexenoic acid (DHA, 22:6 (n-3)) was increased, while linolenic acid (18:2 (n-6)) was slightly and arachidonic acid (20:4 (n-6)) was markedly decreased. Content of histamine in alpha-linolenic acid-treated cells was remarkably lower than that of untreated cells. Accordingly, net histamine release stimulated by antigen or A23187 was also markedly decreased in the alpha-linolenic acid-treated cells, as was the percent histamine release stimulated by antigen. Results from our in vitro experiment suggest that the anti-allergic effect of alpha-linolenic acid may be caused either by the decrease in histamine content or by inhibition of the release of chemical mediator resulting from changes in the fatty acid composition.

Animals↗
PubMed1994

Magnetic resonance imaging and quantitative analysis of contents of epidermoid and dermoid cysts.

The intracapsular cholesterol, protein, and calcium contents of epidermoid and dermoid cysts from seven patients were compared with the signal intensities on T1-weighted spin-echo magnetic resonance (MR) images. All specimens had a paste-like consistency when resected. Epidermoid and dermoid cysts demonstrated a wide range of cholesterol and calcium contents, and epidermoid cysts were not always rich in cholesterol. Five patients had cysts with lower signal intensity than white matter, which contained more than 18.3 mg/g wet weight of protein. One of these patients had the highest cholesterol content of all seven patients (22.25 mg/g wet weight) and another had the highest calcium content (0.75 mg/g wet weight). Two patients had cysts with higher signal intensity than white matter, with protein contents of lower than 4.3 mg/g wet weight. High protein content (> 18.3 mg/g wet weight) may decrease signal intensity on T1-weighted MR images, while low protein content (< 4.3 mg/g wet weight) may increase signal intensity in epidermoid and dermoid cysts with high viscosity (paste-like consistency) contents.

Adolescent↗
PubMed1994

Treatment of autoimmune diseases and systemic vasculitis with pooled human intravenous immune globulin.

Treatment of autoimmune and vasculitic disorders with intravenous immune globulin (IVIG) has shown great promise. IVIG appears to provide large amounts of immunoregulatory substances that have the capacity to regulate the immune system in various ways. The ability of IVIG to regulate deleterious autoimmune responses and disease is largely directly related to its ability to stimulate the production of anti-idiotypic autoantibodies after infusion. In this respect, IVIG represents a novel immunoregulatory agent with the ability to control autoimmune and vasculitic disorders without subsequent predisposition to infectious complications. Future work and controlled clinical trials will be necessary to prove the efficacy of this therapy for specific autoimmune and vasculitic disorders.

Antibodies, Anti-Idiotypic↗
PubMed1992

Suppression of intestinal smooth muscle contraction by phenolic compounds.

Wood creosote, a mixture of guaiacol, creosol, and other related phenolic compounds, suppresses the spontaneous longitudinal phasic contractions of an isolated rat ileal segment. Thirty-two phenolic compounds were screened for this activity to identify the active substances in wood creosote. Of the 32 compounds tested, 2,3,6-trimethylphenol, 2,4,6-trimethylphenol, and 4-ethylguaiacol were most effective and their respective IC50 values were 0.035, 0.037, and 0.043 mM. Guaiacol and creosol, the chief constituents of wood creosote, were moderately effective and their respective IC50 values were 0.18 and 0.13 mM. Other phenolic compounds in wood creosote also suppressed the ileal contraction although their IC50 values differed markedly from each other. These results suggest that practically all of its constituent phenolic compounds contribute to wood creosote's capacity to suppress ileal contraction.

Animals↗
PubMed1991

Length of the human umbilical cord in multiple pregnancy.

The factors controlling the length of the human umbilical cord are uncertain. In the generally accepted 'tension theory', the length of the umbilical cord is proposed to increase the tensile force on it in the uterus. The greatest tensile force is supposed to be fetal movement. If this is so, the length of the umbilical cord should be shorter in multiple pregnancy than in single pregnancy. To examine this possibility we measured the umbilical cord lengths in 3314 singleton births, 82 twins births (164 infants), and 11 triplet or quadruplet births (35 infants). The cord lengths in multiple pregnancies (twins 51.3 cm, triplets and quadruplets 50.1 cm) tended to be shorter than that in singleton pregnancies (57.2 cm). However, no significant difference was found in the ratio of the umbilical cord length to the infant body weight in these groups. Therefore, we conclude that an important factor in determining the cord length is the size of the infant.

Body Weight↗
PubMed1991

Characterization of AL amyloid protein identified by immunoelectron microscopy: a simple method using the protein A-gold technique.

The classification of amyloidosis depends on the chemical nature of the specific amyloid protein involved. Because AL amyloid protein consists mainly of variable regions of light chain (LC), immunohistochemical staining with conventional anti-LC antisera cannot identify its protein. We were able to classify three cases of AL amyloidosis, including one case of AL-kappa LC and two cases of AL-lambda LC, using post-embedding protein A-gold immunoelectron microscopy on autopsy-derived tissues. We describe here our procedure in which a protein A-gold staining apparatus was used. The main advantage of this method is that many sections can be stained and washed simultaneously under the same conditions. These results suggest that the post-embedding protein A-gold technique using conventional kappa or lambda LC may be useful in diagnosing AL amyloidosis.

Amyloid↗
PubMed1991

Characterization of contaminants in EMS-associated L-tryptophan samples by high-performance liquid chromatography.

To identify chemical contaminant(s) associated with eosinophilia-myalgia syndrome (EMS), case and control lots of tryptophan were analyzed by HPLC with both UV and FL detection. Numerous contaminant peaks appeared on the chromatograms and some of them were identified as 5-hydroxytryptophan, indol aldehyde, indol, etc; from the retention time of authentic compounds. Among these, three peaks were significantly associated with case lots. One corresponds to di-tryptophan aminal of aldehyde (peak E). Others are unknown contaminants, UV-5 (FL-7) and UV-28 (FL-36). The structural elucidation and toxicological implication of UV-5 (FL-7) are currently in progress.

Chromatography, High Pressure Liquid↗
PubMed1990

Serum interleukin-2 levels in a patient with focal segmental glomerulosclerosis. Relationship to clinical course and cyclosporin A therapy.

We describe a patient with steroid-resistant focal segmental glomerulosclerosis (FSGS) whose serum interleukin-2 (IL-2) levels were markedly elevated in association with disease activity. With cyclosporin A (CsA) treatment, the patient entered remission and serum IL-2 fell to undetectable levels. After cessation of CsA, the patient relapsed and the serum IL-2 levels were elevated again. Reinstitution of CsA therapy was followed by a partial remission and disappearance of detectable serum IL-2 levels.

Cyclosporins↗
PubMed1990

Exogenous interleukin-2 does not reverse the immunoinhibitory effects of 1,25-dihydroxyvitamin D3 on human peripheral blood lymphocyte immunoglobulin production.

1,25-Dihydroxyvitamin D3 (1,25-D3) is known to have potent inhibitory effects on human peripheral blood mononuclear cell (PBMC) functions. Previous experiments suggest that addition of interleukin-2 (IL-2) to cell cultures can reverse the antiproliferative action of 1,25-D3. Previous studies have also shown that the CD4+ T-cell subset is more sensitive to the antiproliferative actions of 1,25-D3 than are the CD8+ T-cells. The objective of this study was to determine whether exogenous IL-2 could reverse the antiproliferative and immunoinhibitory action (inhibition of Ig production) in mitogen-activated PBMC cultures and in fluorescein-activated cell sorting (FACS) experiments where CD8+ T-cells were removed from PBMCs before mitogen stimulation with/without exogenous IL-2 added. In these studies, addition of IL-2 to mitogen-activated, 1,25-D3-treated PBMCs allowed the cells to overcome the 1,25-D3 suppressive effect on cell proliferation. However, exogenous IL-2 did not overcome the 1,25-D3-mediated inhibitory effect on PBMC Ig production. Using FACS lymphocyte populations (CD4+, CD8+ and B-cells), we showed that CD4+ T-cell-directed Ig synthesis in co-culture with autologous B-cells was inhibitable by incubation of cells with 1,25-D3, but Ig synthesis was restored to near-normal levels by addition of exogenous IL-2. This clearly contrasts with the inability of Il-2 to reverse the 1,25-D3 inhibitory effect on Ig synthesis in PBMCs. In other experiments, when CD8+ cells were removed from mitogen-stimulated, 1,25-D3-treated PBMCs, addition of exogenous IL-2 resulted in a full reversal of the 1,25-D3-mediated Ig inhibition. These data suggest that the inability of IL-2 to reverse the inhibitory effects of 1,25-D3 on PBMC Ig production is probably a result of a lack of sensitivity of CD8+ T-cells to the antiproliferative and immunoregulatory actions of 1,25-D3. This is possibly because of a differential expression of 1,25-D3 receptors on CD4+ and CD8+ T-cells.

B-Lymphocytes↗
PubMed1990

Metabolic and hematologic effects and immune complex formation related to pertussis immunization.

Selected metabolic, hematologic, and immunologic functions were evaluated in 3- to 6-mo-old Finnish infants who received whole-cell pertussis-component diphtheria and tetanus toxoids and pertussis vaccine, adsorbed (DTP) vaccine, and in 4- to 6-y-old Los Angeles children who received either a licensed DTP vaccine or an acellular pertussis component DTP vaccine. One d after immunization, there was an increase in total leukocytes and neutrophils and a decrease in lymphocytes in all vaccinees. In 4- to 6-y-old children the leukocytosis and neutrophilia were greater in recipients who received the standard DTP vaccine than in vaccinees who received an acellular pertussis component DTP vaccine. In infants there was an increase in the mean plasma insulin concentration but no change in the glucose concentration 24 h after immunization; no increase in the mean plasma insulin was noted in the 4- to 6-y-old children. Three 4- to 6-y-old vaccinees had higher circulating immune complex concentrations after immunization and two of these children had high clinical reaction scores. The etiology of adverse reactions after DTP immunization is multifactorial. In contrast with findings in animals, our findings do not demonstrate a clinically significant effect due to lymphocytosis-promoting factor on glucose metabolism in vaccinated children. Neutrophilia in vaccinees is probably due to endotoxin, and some reactions may be due to circulating immune complexes.

Antigen-Antibody Complex↗
PubMed1990

[Studies on chemical analysis of mycotoxin (XXI). A rapid analytical method for aflatoxins by immunoaffinity column chromatography and high performance liquid chromatography].

An analytical method for aflatoxins using solvent extraction, affinity column (containing monoclonal antibodies against aflatoxins bound onto agarose) clean-up and high performance liquid chromatographic determination was applied to the analysis of aflatoxins in peanuts, pistachio nuts, white and black peppers and corn. Recoveries of aflatoxins B1, B2, G1 and G2 spiked to peanuts, pistachio nuts and corn at the level of 20 ppb were 77.4-81.4, 70.1-77.9 and 72.3-94.8%, respectively. In the case of white and black peppers, because the spiked aflatoxin recovery rate was low, further purification steps should be studied. The stability of the affinity column was good. This procedure is recommended as a rapid and reliable method for the analysis of aflatoxins in the three kinds of foods, peanuts, pistachio nuts and corn.

Aflatoxins↗