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Biomedical subjects

H Nakao

Publications and source records attributed to H Nakao.

At least 163 records · Page 9Linked to original sources
PubMed1989

Purification and some properties of a novel L-2,4-diaminobutyric acid decarboxylase from Vibrio alginolyticus.

Previous investigations have shown that members of the genus Vibrio possess a novel enzyme activity decarboxylating L-2,4-diaminobutyric acid (DABA) to 1,3-diaminopropane (DAP). In this paper we describe the purification, by about 3600-fold, of the enzyme from V. alginolyticus. The purified enzyme was apparently homogeneous, and had a specific activity of 4200 nmol DAP min-1 (mg protein)-1. The enzyme protein has an Mr of 450,000 +/- 20,000 and is apparently comprised of four identical subunits (Mr 109,000 +/- 1,000). Neither 2,3-diaminopropionic acid, ornithine, lysine nor arginine served as substrates. Some properties of the enzyme were determined. Cultivation of this bacterium in the presence of added DABA brought about increased production of norspermidine (NSPD), characteristically present in this species as well as DAP, suggesting that the enzyme may be functionally implicated in the formation of DAP, a biosynthetic precursor of NSPD.

Aminobutyrates↗
PubMed1989

Analysis of surface antigen expression of human immunoglobulin-secreting cells: phenotypic heterogeneity in normal counterparts of myeloma cells.

Human myeloma cells are malignant counterparts of plasma cells which represent the most differentiated B cells. Myeloma cells are, however, heterogeneous in their surface antigen expression (Katagiri et al, 1984, 1985), which may reflect that normal plasma cells have a spectrum of differentiation. To test this hypothesis, immunoglobulin-secreting cells (ISC) of non-neoplastic nature were studied with regard to their surface antigen expression by using a combination of reverse haemolytic plaque assay and complement-dependent cytolysis. Non-neoplastic ISC were found to have a broad spectrum of differentiation stages from the immature type of CD20+, HLA-DR+, CD38+ in the peripheral blood to the mature type of CD20-, HLA-DR-, CD38+ in the bone marrow. In patients with polyclonal B cell activation (PBA), ISC showed a more immature antigen expression in comparison with ISC in normal controls or patients without PBA. The surface antigen development of ISC was clearly demonstrated throughout the stages in the analysis of mitogen-induced ISC in vitro. No significant difference in the surface phenotype of ISC was found among heavy chain classes. Thus, non-neoplastic ISC show a spectrum of differentiation similar to that of myeloma cells, depending on the site where ISC are located, and on the degree of PBA in vivo.

Antibody-Producing Cells↗
PubMed1989

New approach to eliminate HLA class I antigens from platelet surface without cell damage: acid treatment at pH 3.0.

A new method was studied for eliminating HLA class I antigens from the surface of platelets without damaging the cells. Platelets were exposed to an acid solution (pH 3.0) to eliminate the antigenicity of HLA class I antigens. The reduction in antigenicities of HLA class I common antigen and individual HLA class I antigens by acid treatment was marked. Patients' sera which contained multispecific HLA antibodies reacted with PBS-treated platelets, but not with acid-treated platelets. No changes were observed in the antigenicities of glycoprotein Ib or glycoprotein IIb/IIIa. The viability of acid-treated platelets was 83%. Ultrastructural investigations revealed no significant difference between the PBS-treated platelets and acid-treated platelets. The platelet function studies showed that the aggregation of acid-treated platelets induced by various agonists was only slightly reduced compared with PBS-treated platelets. We propose that acid-treated platelets are promising for clinical use in patients refractory to platelet transfusions and may be superior to chloroquine-treated platelets for analysis of the specificity of antiplatelet antibodies.

Blood Platelets↗
PubMed1989

Schizophrenic neologism versus aphasic neologism: characteristics in writings of Japanese schizophrenic patients.

Three cases of schizophrenia with ideographic neologisms in Japanese are presented and compared with aphasic neologisms reported in Japanese literature. Schizophrenic neologisms are different from aphasic neologisms in nature. The contrast becomes obvious when both are compared in Japanese writing based on the dual writing system of kanji (Chinese characters, ideogram) and kana (phonetic characters, syllabogram).

Adult↗
PubMed1989

Interleukin-1 production and action in thyroid tissue.

This study was undertaken to determine the effects of interleukin-1 (IL-1) on human thyroid epithelial cells (thyrocytes) and whether thyrocytes produce IL-1. The supernatants of cultured peripheral blood monocytes stimulated with lipopolysaccharide (LPS) increased [3H]thymidine incorporation into thyrocytes from normal subjects and patients with Grave's disease. The IL-1 levels of cultured supernatants of monocytes were measured by a thymocyte costimulation assay and a solid phase sandwich immunoenzymometric assay. The supernatants of monocyte cultures stimulated with LPS contained significant amounts of IL-1 bioactivity and IL-1 alpha and IL-1 beta immunoactivity. Recombinant IL-1 beta (rIL-1 beta) also stimulated [3H]thymidine incorporation into thyrocytes from normal subjects and patients with Graves' disease, and it increased the proportion of thyrocytes in the S phase of the cell cycle. Furthermore, thyrocytes stimulated with rIL-1 beta for 24 h produced significant amounts of prostaglandin E2. Indomethacin inhibited completely the rIL-1 beta-stimulated prostaglandin E2 production and increased markedly [3H]thymidine incorporation. IL-1-like activity also was detected in the cultured supernatants of lipopolysaccharide (LPS)-stimulated thyrocytes from Graves' and normal thyroid glands, but the amount of IL-1-like activity secreted by thyrocytes was significantly less than that secreted by circulating monocytes. The kinetics of the release of IL-1-like activity by thyrocytes were similar to those of its production by circulating monocytes. Pretreatment of thyrocytes with interferon-gamma failed to enhance the release of IL-1-like activity. Moreover, IL-1 alpha or IL-1 beta immunoreactivity could not be detected in the supernatants of LPS-stimulated thyrocytes, despite the presence of IL-1-like bioactivity. No IL-1 alpha mRNA was detected in unstimulated thyrocytes or thyrocytes stimulated with LPS and phorbol myristate acid. These findings demonstrate that thyrocytes produce an IL-1-like substance(s), but not IL-1, when stimulated by LPS. We conclude that IL-1 may regulate the proliferation of thyrocytes and that local production of IL-1 by infiltrating monocytes may contribute to the development of goiter in patients with autoimmune thyroid diseases.

Biological Availability↗
PubMed1989

Abnormal B lymphocyte function in thyroid glands from patients with Graves' disease.

Thyroid-infiltrating B lymphocytes from patients with Graves' disease were investigated in regard to their phenotypic profiles, cell size, cell cycle status, proliferative response to Staphylococcus aureus Cowan 1 (SAC), and spontaneous production of immunoglobulin G (IgG) and antithyroidal autoantibodies. Thyroid tissues and peripheral blood were obtained at the time of subtotal thyroidectomy of 27 Graves' patients who had been treated with thionamide drugs and iodide before operation. Two intrathyroidal mononuclear cell populations were obtained from these thyroid tissues. One cell population was isolated from the supernatants after mechanical disaggregation of the tissues and was defined as TG-1 cells. Another cell population, defined as TG-2 cells, was isolated from the supernatants of overnight cultures of the thyroid debris after enzymatic digestion. The percentages of B lymphocytes bearing activated markers and plasma cells (CD20+CD21-, IgM+IgD-, CD20+ transferrin receptor+, PCA-1+) were significantly higher in the TG-1 and TG-2 cell populations than in peripheral blood from Graves' disease patients and normal subjects. These phenotypic changes were accompanied by increased thyroid gland B lymphocyte cell size from patients with Graves' disease. The proliferative response of B lymphocytes to SAC was markedly lower in TG-1 and TG-2 cell populations than in peripheral blood cells from Graves' disease patients and normal subjects. B lymphocytes isolated from thyroid glands secreted significantly more IgG and antithyroidal autoantibodies than those from peripheral blood. Based on the findings of abnormalities in thyroid-infiltrating B lymphocytes, we suggest that activated B lymphocytes may induce the excessive production of antithyroidal autoantibodies in thyroid glands from patients with Graves' disease.

Adult↗
PubMed1989

Studies on orally active cephalosporin esters. II. Chemical stability of pivaloyloxymethyl esters in phosphate buffer solution.

The degradation kinetics of pivaloyloxymethyl (POM) esters of cephalosporins in phosphate buffer solution (pH 6-8) were investigated. The degradation of the starting delta 3 cephalosporin ester proceeded mainly via isomerization to the delta 2 ester and subsequent hydrolysis to the delta 2 acid. Hydrolysis to the delta 3 acid (the parent acid) was very slow. Analysis of the rate constants indicated that the isomerization rate k12 was approximately equal to the apparent degradation rate of the delta 3 ester kdeg, and slower than the hydrolysis rate of the delta 2 ester k24. The isomerization process to the delta 2 ester was found to be the rate-determining step in the degradation of cephalosporin esters. The substituent at the C-3 position of the cephalosporins affected the degradation kinetics. The degradation was accelerated by increase of pH, buffer concentration and added protein.

Administration, Oral↗
PubMed1989

Studies on orally active cephalosporin esters. III. Effect of the 3-substituent on the chemical stability of pivaloyloxymethyl esters in phosphate buffer solution.

The effect of substituents at the C-3 position on the degradation kinetics of the pivaloyloxymethyl (POM) ester of delta 3 cephalosporin in phosphate buffer solution (pH 6-8) was investigated. In the degradation, the isomerization process to the delta 2 ester was the rate-determining step. In this study, the logarithm of the isomerization rate to the delta 2 ester (log k12) correlated with the carbon-13 nuclear magnetic resonance chemical shift difference value at C-3 and C-4 of the delta 3 ester (delta delta (4-3)). The energy level of the lowest unoccupied molecular orbital (LUMO) of the delta 3 esters also correlated with log k12. The electronic properties at the C-2 position had no effect on the isomerization reaction. On the other hand, the logarithm of the isomerization rate back to the delta 3 ester (log k21) correlated with the van der Waals volume (MV) of the 3-substituent. These results show that the substituent at the C-3 position influences mainly the electronic structure of the conjugated pi-bond system (C3 = C4 - C4 = O) and consequently affects the feasibility of isomerization to the delta 2 ester, i.e., the stability to degradation.

Administration, Oral↗
PubMed1989

Formation of hydroxynorspermidine from exogenously added 1,3-diaminopropan-2-ol in Vibrio species.

When Vibrio parahaemolyticus AQ 3627 was grown in the presence of 1,3-diaminopropan-2-ol (OH-Dap), a new compound accumulated in the cells. This was identified as hydroxynorspermidine (OH-Nspd), N-(3-aminopropyl)-1,3-diaminopropan-2-ol, by gas chromatography-mass spectrometry and thin-layer chromatography. It was also synthesized enzymatically from OH-Dap by a cell-free preparation from this strain. All other Vibrio strains examined also showed the ability to synthesize this compound, but none of the non-vibrio organisms did, indicating that OH-Dap is an in vivo substrate for the enzyme responsible for biosynthesis of norspermidine characteristically present in vibrios. These results suggest that the ability to synthesize OH-Nspd from OH-Dap present in the growth medium may be useful as an additional identifying factor for the genus Vibrio.

Biotransformation↗
PubMed1989

Enzyme-immunoassay for estrogen receptors in human pituitary adenomas.

We have performed an enzyme-immunoassay for estrogen receptor on 56 human pituitary adenomas and compared the results with a single point estradiol binding assay. There was a significant positive correlation between the two assays of cytoplasmic estrogen receptor (r = 0.960). Normal human pituitaries (N = 2) had an estrogen receptor concentration of 17 fmol/mg protein by enzyme-immunoassay. Of 14 prolactinomas, 6 (43%) contained estrogen receptor with a concentration of 33.5 +/- 7.4 (mean +/- SEM) fmol/mg protein. Six of 11 (55%) macroprolactinomas were estrogen receptor-positive, whereas all 3 microprolactinomas were estrogen receptor-negative. Only one (13%) of 8 GH- and PRL-secreting adenomas, and 3 of 6 (50%) gonadotropin-secreting adenomas were estrogen receptor-positive; the latter had a concentration of 13.5 +/- 1.6 fmol/mg protein. Estrogen receptor was not detected in 21 pure GH-secreting adenomas and 7 nonsecreting adenomas. These results demonstrate the precise frequency of estrogen receptor in various human pituitary adenomas, since enzyme-immunoassay as well as single point estradiol binding assay could detect estrogen receptor even in small specimens. Enzyme-immunoassay is suitable for evaluation of estrogen receptor status in human pituitary adenomas.

Adenoma↗
PubMed1989

Cytotoxic activity of interleukin-2 (IL-2) activated killer cells toward thyroid epithelial cells.

We investigated the sensitivity of thyroid epithelial cells (thyrocytes) to IL-2 activated killer cells. The thyrocytes were lysed by autologous and allogeneic IL-2-activated killer cells; there were no differences in sensitivity to the killer cells between normal thyrocytes and thyrocytes from patients with Graves' disease. When thyrocytes were pretreated with recombinant interferon (rIFN) gamma or alpha, the IL-2-activated killer cell-mediated cytotoxicity was depressed and varied inversely with the cell surface expression of class I HLA gene products. The rIFN-gamma pretreatment did not alter the kinetics of thyrocytes lysis by IL-2-activated killer cells. Using cold target competition analysis, rIFN-gamma-pretreated thyrocytes clearly competed less effectively than did untreated cells for lysis of untreated target cells. These results suggest that rIFN-gamma or IFN-alpha pretreatment of thyrocytes may reduce their ability to be recognized by effector cells. These findings suggest that destruction of thyrocytes in autoimmune thyroiditis may be, in part, due to IL-2-activated killer cells and may be regulated by IFN.

Cells, Cultured↗
PubMed1989

Increment of Tal positive cells in peripheral blood from patients with rheumatoid arthritis.

Recently it was demonstrated that the Tal antigen is a marker for activated T cells and the population of Tal+ cells includes memory T cells. Our study was undertaken to analyze Tal+ cells in peripheral blood from patients with rheumatoid arthritis (RA) and examine the correlation between the proportion of Tal+ cells and disease activity. Using a dual immunofluorescent method, T cell subsets were analyzed in peripheral blood from 46 patients with RA, 10 patients with osteoarthritis (OA) and 10 healthy subjects. Patients with RA had a significantly higher percentage of T cells bearing the Tal antigen than patients with OA and healthy subjects. Furthermore, the percentage of CD3+Tal+ cells in peripheral blood from patients with RA was significantly correlated with disease activity including erythrocyte sedimentation rate, morning stiffness and the Lansbury index, whereas CD3+ HLA-DR+ cells did not correlate. In serial observations in patients with RA, the percentage of CD3+ Tal+ cells decreased in accordance with the improvement of disease activity. Thus, we suggest that the percentage of Tal+ cells may be a marker of the disease activity in patients with RA.

Aged↗
PubMed1989

[Sialyl Lewis(x)-I (SLX) as a tumor-associated carbohydrate antigen in sera in patients with gastric and colorectal cancer--evaluation according to clinico-pathological factors].

Sialyl Lewis(x)-i (SLX) as a new tumor-associated antigen was assayed in sera of 133 gastric cancer and 62 colorectal cancer patients with preoperative state in order to elucidate the clinico-pathological features. The percent positives in sera of patients with gastric and colorectal cancer were 12.7% (17/133) and 16.1% (10/62), respectively, and there were few positive cases in the early stages. Therefore, it is suggested that the early diagnosis for gastric and colorectal cancer using SLX alone may be difficult. However, it is revealed that SLX has a high tumor-specificity in consideration of the clinico-pathological properties such as H, P, n, ly, v factors, depth of cancer invasion and operative radicality. These data suggested that SLX could be applicable as a useful tumor-marker which shows the metastasis or extension of carcinoma.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1989

Elevation of a tumor associated antigen CA 19-9 levels in patients with rheumatic diseases.

We investigated the incidence and characteristics of an elevated tumor associated antigen CA 19-9 in patients with rheumatic diseases. Serum concentration of CA 19-9 was increased in 13 of 39 patients (33.3%) with definite or classical rheumatoid arthritis (RA), in 6 of 19 patients (31.6%) with systemic lupus erythematosus (SLE), in 3 of 9 patients (33.3%) with progressive systemic sclerosis (PSS) and in 9 of the other 35 patients (25.7%). Malignant neoplasm was not detected in any of the patients with rheumatic diseases. Pretreatment of mouse serum with patients' sera did not reduce the measured CA 19-9 values obtained by the conventional assay. The CA 19-9 antigen found in sera from patients with RA was present in a non-IgG fraction, and had the same molecular weight as that in one patient with pancreatic cancer, as determined by gel filtration. These results demonstrated that serum CA 19-9 levels were increased in some patients with rheumatic diseases.

Adult↗
PubMed1989

[A case of progressive systemic sclerosis accompanied with rheumatoid arthritis].

A 37-year old man was suffered from Raynaud's phenomenon, sclerodactyly, and polyarthritis involving knees, shoulders, and hands. Recurrent skin ulcers were present in finger tips. Laboratory studies showed positive RA test, antinuclear antibody (nucleolar type), and anti-Scl 70 antibody. So diagnosis of progressive systemic sclerosis (PSS) was made. Progressed destructive arthritis with rheumatoid nodules developed in the patient. The joint destruction was severe and he was satisfied with the criteria of the American Rheumatism Association (ARA). This patient appears to be an overlapping case of PSS and rheumatoid arthritis (RA).

Adult↗
PubMed1989

[Changes of protein and RNA content in accumulated G1 cells by delta12-PGJ2].

Protein and RNA content in accumulated G1 cells was measured with B16 melanoma cells by flow cytometer to study the mechanism of antineoplastic action of delta 12PGJ2. DNA histogram showed that, after a 6 hr exposure to delta 12PGJ2, the percentage of tumor cells in G2M phase increased, and G1 accumulation with depletion of cell population in S phase was seen after 12-24 hr exposure to 2.0 micrograms/ml of delta 12 PGJ2. Protein content in accumulated G1 cells increased at 6 hr after exposure, and subsequently decreased. However, the protein content treated with delta 12PGJ2 was higher than that of the control. A reduction of RNA content in G1 cells was seen after delta 12PGJ2 exposure. As the result, it was found that delta 12PGJ2 made cell progression ceased in G1 phase of cell cycle, and where protein and RNA content was higher than that of control. It is suggested that some hyper-metabolite state was caused by delta 12 PGJ2 in cultured B16 melanoma cells.

Antineoplastic Agents↗
PubMed1988

Cardiac arrhythmias induced in cats by stimulation of the anteromedial hypothalamus.

Negative emotional behavior induced during stimulation of the anteromedial hypothalamus is frequently accompanied by cardiac arrhythmias just after cessation of the stimulation (the poststimulus arrhythmias: the PSAs). A mechanism related to the PSAs may be neurogenic in origin. Whether or not the PSAs are influenced by hypothalamically induced adrenal catecholamines has not been settled. We assessed the correlation between these influences on the PSAs induced by anteromedial hypothalamic stimulation in anesthetized cats. Thirty-five adult cats were given stimulation through an electrode inserted stereotaxically into the hypothalamus and arterial blood pressure, electrocardiogram and heart rate were recorded on a polygraph. PSAs were never observed after vagotomy and intravenous injections of methyl-atropine and phentolamine. Carteolol was without effect. When an intentional gradual reduction of stimulus intensity was applied instead of sudden cessation of hypothalamic stimulation, there was a gradual decline in the blood pressure and no PSAs. Adrenalectomy did not alter the threshold for the PSAs but did reduce the frequency of the PSAs. Intravenous injections of catecholamines produced cardiac arrhythmias similar to those seen in PSAs. After vagotomy, stimulation of the distal nerve of the right vagus during or just after hypothalamic stimulation produced the same arrhythmias as seen in PSAs, but vagus stimulation alone did not. These results suggest that the PSAs are due to 'sudden' change from sympathetic to parasympathetic influences on the heart and that adrenal catecholamines are involved in the prolongation of the train of the PSAs. These findings support the proposal that the PSAs are a stress-related symptom induced by stimulation of the anteromedial hypothalamus.

Adrenal Medulla↗