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Biomedical subjects

M Matsunaga

Publications and source records attributed to M Matsunaga.

At least 127 records · Page 7Linked to original sources

A novel antibody against a synthetic NH2-terminal myristoyl glycyl src peptide can detect pp60v-src, the transforming protein of Rous sarcoma virus.

Novel antibodies were raised against a synthetic NH2-terminal myristoyl(Myr-) tetrapeptide(N-Myr-Gly-Ser-Ser-Lys) which is characteristic of an NH2-terminal portion of pp60v-src, the transforming protein of Rous sarcoma virus. Antisera raised against N-Myr-Gly-Ser-Ser-Lys-haemocyanin reacted with 125I-albumin conjugates with N-Myr-Gly-Ser-Ser-Lys. The immunoreaction was competed for by haemocyanin as well as albumin conjugated with this N-Myr-peptide, while underivatized proteins or an NH2-terminal octapeptide (Gly-Ser-Ser-Lys-Ser-Lys-Pro-Lys) had no effect. N-Myr-Gly-Ser-Ser-Lys-(125I)tyramine was also recognized by the antibody. The reaction was competed for by N-Myr-Gly-Ser-Ser-Lys, but not by Gly-Ser-Ser-Lys-Ser-Lys-Pro-Lys. These results suggest a high affinity of the antibody for an N-Myr-peptide moiety. The major (3H)myristate-labelled protein of an apparent molecular weight of 60,000 was detected from chick embryo fibroblasts transformed by Rous sarcoma virus (tsNY68). This protein was demonstrated to possess N-Myr-Gly-Ser-Ser-Lys by the immunoprecipitation and HPLC analyses. Furthermore, the entire circumference of the transformed cells was stained by the antibody upon an immunofluorescent microscopic observation. Thus, these results taken together indicate that the haptenic antibody raised against the myristoyl peptide is useful to detect pp60v-src protein.

Amino Acid Sequence↗

Calculation of membrane potential in synaptosomes with use of a lipophilic cation (tetraphenylphosphonium).

To estimate membrane potential in synaptosomes with the use of tetraphenylphosphonium (TPP+), an equation relating the amount of TPP+ accumulated in synaptosomes with membrane potential was derived from the following two assumptions. (1) TPP+ molecules were distributed into plasma membranes, mitochondria and cytosol of synaptosomes. (2) TPP+ achieves a Nernst equilibrium across both the synaptosomal and inner mitochondrial membranes. We propose three methods for calculation of membrane potential using this equation. The concentration of TPP+ was measured under various controlled conditions with an electrode selective for TPP+. The amount of TPP+ accumulated in synaptosomes was determined by measuring the difference between its initial concentration and the concentration after addition of synaptosomes, and membrane potential was estimated by the three methods. The resting potential of synaptosomes was estimated to be -75 to -90 mV by all of these methods. Membrane potentials under various controlled conditions were calculated, and the characteristics of the methods for estimation of membrane potential and those of membrane potential obtained by the methods are discussed.

Animals↗

Arteriovenous malformation of the corpus callosum associated with persistent primitive trigeminal artery--case report.

A 16-year-old girl with a large, ruptured arteriovenous malformation (AVM) of the corpus callosum was studied by computed tomography and angiography. The relatively large nidus of the AVM was located mainly in the anterior portion of the corpus callosum, and there was a smaller nidus in the splenium. She also had a persistent primitive left trigeminal artery (PTA). This is the first reported case of an AVM with extensive callosal involvement associated with a PTA. She underwent radiation therapy and remained asymptomatic for 2 years thereafter.

Adolescent↗

[Relationship between pocket reduction and plaque control in initial treatment].

It has been suggested that plaque control is important in periodontal treatment. This study used O'Leary's plaque control record (PCR) to investigate the influence of plaque control in initial treatment. Thirty patients (18 men and 12 women, mean age 46.7 years) were selected for this study. The results were as follows: The mean pocket depth was reduced from 3.19 mm (at the first examination) to 2.11 mm (at re-evaluation). Mean pocket depth of 3 mm or more at the first examination was reduced from 4.09 mm to 2.43 mm. The mean number of times plaque control instruction was given to reduce the PCR 10% or less was 3.8. The quantity of pocket reduction was significantly greater in the group that underwent instructions to reduce the PCR 10% or less 4 times or less compared with the group that underwent instructions 5 times or more. The group whose mean PCR was 10% or less from the time 10% or less at the first time to re-evaluation, had significantly greater pocket reduction than the group with 20% or more. There was no correlation between pocket reduction and PCR at the first examination and bone loss scores obtained from X-ray films.

Dental Plaque↗

Effects of co-culture with vascular endothelial cells on the renin-like enzyme production in vascular smooth muscle cells.

Cultured human vascular smooth muscle cells (VSMC) produced an immunologically specific renin-like enzyme. The production of the renin-like enzyme was increased by 1 mM N6-O2'-dibutyryladenosine 3',5' cyclic monophosphoric acid sodium salt (db-cAMP). When co-cultured with human vascular endothelial cells (EC) and human skin fibroblast (FB), the basal production of the renin-like enzyme was increased. And the extent of the increase by db-cAMP was amplified by co-culture with EC, but not by the co-culture with FB.

Cells, Cultured↗

Unique mixed lymphocyte-stimulating determinants in Ed alpha gene-introduced C57BL/6 transgenic mice.

A unique mixed lymphocyte-stimulating determinant(s) was detected in Ed alpha gene-introduced C57BL/6 transgenic mice using alloreactive T-cell clones. Such unique determinant(s) was not detected by primary mixed lymphocyte culture reactions. The possibility that such unique determinant(s) was created by the combinatorial association of Ed alpha transgene products with endogenous Ab beta gene products is discussed.

Animals↗

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↗

Blockage of morphological transformation of chick embryo fibroblasts infected with Rous sarcoma virus by N-myristoyl glycinal diethylacetal in vitro.

N-Myristoyl glycinal diethylacetal strongly inhibited morphological transformation of chick embryo fibroblasts infected with a temperature-sensitive mutant (tsNY68) of Rous sarcoma virus. Myristoylated or nonmyristoylated pp60v-src, which were expressed in tsNY68-infected cells in the absence or presence of the compound, were identified separately by fluorography or immunoblotting analysis after sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the [3H]myristate-labeled cell lysate. The results taken together suggest that the blockage of morphological transformation was caused by prevention of protein myristoylation of the transforming protein pp60v-src.

Acetaldehyde↗

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↗

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↗

[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↗

Sympathetic skin response in diabetic neuropathy.

Sympathetic function test was undertaken using the sympathetic skin response (SSR), a technique for assessment of sudomotor activity, in 67 diabetics, and the results were compared with those from 45 age-matched normal subjects. The SSR was readily elicitable in normal subjects, but absent in six patients with diabetes. In 28 patients, the SSR was preserved, but their amplitude was below the normal range. The decrease in the SSR amplitude correlated well with a fall in motor and sensory conduction velocity. The SSR magnitude correlated well to the impaired R-R interval variation during deep breathing and the heart rate increase and the blood pressure change on standing, indicating a close correlation between the disturbance of sudomotor function and that of other sympathetic and parasympathetic functions. Most of the patients with clinical evidence of dysautonomia and with insulin treatment revealed diminished or absent SSR.

Adolescent↗

Guidance of optic nerve fibres by N-cadherin adhesion molecules.

The dendritic branches (neurites) of developing neurons migrate along specific pathways to reach their targets. It has been suggested that this migration is guided by factors present on the surface of other neurons or glial cells. The molecular nature of such factors, however, remains to be elucidated. N-cadherin is a cell-surface glycoprotein which belongs to the cadherin family of cell-cell adhesion molecules. This adhesion molecule is expressed in various neuronal cells as well as in glial cells of the central and peripheral nervous systems in vertebrate embryos and recent immunological studies suggested that N-cadherin may play a role in guiding the migration of neurites on myotubes or astrocytes. To further examine this possibility, we used a molecular-genetic approach; that is, we examined the outgrowth of chicken embryonic optic axons on monolayer cultures of Neuro 2a or L cells transfected with the complementary DNA encoding chicken N-cadherin. The data indicate that N-cadherin is used as a guide molecule for the migration of optic axons on cell surfaces.

Animals↗

Role of N-cadherin cell adhesion molecules in the histogenesis of neural retina.

We investigated the role of N-cadherin cell adhesion molecules in the histogenesis of the chicken neural retina. In the undifferentiated retina of early embryos, N-cadherin is almost evenly distributed. With differentiation, N-cadherin was gradually localized in particular cell layers. In the 8.5 to 10.5 day embryos, N-cadherin was most abundant in the optic nerve fiber layer, the plexiform layers and the outer limiting membrane. Thereafter, this molecule gradually diminished from most parts of the retina, except in the outer limiting membrane. When incubated with Fab fragments of a polyclonal antibody to N-cadherin, retinas of early embryos tended to dissociate and could not be maintained as a tissue mass. Retinas from older embryos were not dissociated by the Fab, but their morphogenesis was severely affected. We conclude that N-cadherin is essential for maintaining the overall structure of the undifferentiated retina, but during development, its role becomes restricted to maintaining more specific regions of the tissue. We also suggest that there might be additional, unidentified cadherin-like molecules in the retina.

Animals↗

Detection of low molecular kininogen messenger RNA in human kidney.

The purpose of the present study was to confirm expression of kininogen in human kidneys. As the human kininogen gene is alternatively transcribed to high molecular weight and low molecular weight kininogen messenger (m)RNA, we constructed a probe which can discern these two transcripts by the S1 nuclease mapping analysis. The low molecular weight kininogen mRNA was detected in human kidney cortex and medulla. This finding strongly supports the existence of a local kinin-kallikrein system in human kidneys.

Blotting, Northern↗

Natural killer and natural killer-like cell activity of peripheral blood and intrathyroidal mononuclear cells from patients with Graves' disease.

This study was undertaken to investigate the natural killer (NK) and natural killer-like (NK-like) cell cytotoxic activity toward autologous thyrocytes of peripheral blood mononuclear cells (PB-MNC) and thyroid gland mononuclear cells (TG-MNC) from previously hyperthyroid patients with Graves' disease, and the effects of recombinant interleukin-2 on such cytotoxic activity. The average cytotoxicities of PB-MNC from Graves' patients toward K562 cells (NK-sensitive cells), Raji cells (NK-resistant cells), and autologous thyrocytes were 23.9 +/- 10.8 (+/- SD) lytic units (LU), 7.4 +/- 3.8 LU, and 11.7 +/- 4.4 LU, respectively. There were no differences in the NK and NK-like cell activity of PB-MNC between Graves' disease patients and normal subjects. In contrast to PB-MNC from patients with Graves' disease, NK and NK-like cell activity was markedly decreased in TG-MNC (NK cell activity, 2.1 +/- 2.3 LU; NK-like cell activity, 1.5 +/- 1.5 LU). TG-MNC from Graves' patients had no cytotoxic activity against autologous thyrocytes. Using the monoclonal anti-Leu 7 and anti-CD16 antibodies and a two-color immunofluorescence method, the NK cell subsets were examined in PB-MNC and TG-MNC from Graves' patients. The percentage of CD16+ cells was significantly decreased in TG-MNC compared to PB-MNC, whereas there was no significant difference in the percentage of Leu 7+ cells between PB-MNC and TG-MNC. Incubation of TG-MNC with medium only did not increase the NK and NK-like cell activity of these cells. Furthermore, incubation of autologous PB-MNC with supernatants of minced thyroid tissues did not alter their NK and NK-like cell activity. The decreased NK and NK-like cell activity of TG-MNC was augmented when these cells were incubated with recombinant interleukin-2. These results suggest that the reduction of NK cell activity in TG-MNC may allow perpetuation of B-cell activation and lead to excessive production of autoantibody in thyroid tissue.

Adolescent↗

Phenotypic analyses and concanavalin-A-induced suppressor cell dysfunction of intrathyroidal lymphocytes from patients with Graves' disease.

The expression of phenotypic markers and Concanavalin-A-induced suppressor activity was compared among mononuclear cells isolated from thyroid glands and peripheral blood of thionamide-treated patients with hyperthyroid Graves' disease and peripheral blood from normal subjects. Intrathyroidal lymphocytes were obtained by two different methods (TG-1 and TG-2 cells), gradient centrifugation of supernatants of minced thyroid tissue and overnight culture of thyroid debris after mechanical disaggregation and enzymatic digestion, respectively. The percentages of CD3+ cells (all mature T cells) among peripheral blood and TG-1 and TG-2 cells from Graves' patients were similar, but the percentages of B1+ cells (pan B cells) among the TG-1 and TG-2 cells were markedly increased compared to that in peripheral blood. The percentages of CD4+ cells among the TG-1 and TG-2 cells were significantly less than that in peripheral blood. The percentages of CD4+2H4+ cells among CD4+ cells in TG-1 and TG-2 cells also were significantly less than that in peripheral blood. The percentage of CD4+4B4+ cells among CD4+ cells in thyroid glands was markedly higher than that in peripheral blood. The percentages of CD8+ cells and CD8+CD11b- cells (cytotoxic T cells) in thyroid glands were significantly higher than those in peripheral blood from Graves' patients and peripheral blood from normal subjects. The CD8+CD11b+ cells were subdivided into two subpopulations on the basis of CD8 antigen density. The percentage of dull CD8+CD11b+ cells (natural killer cells) among TG-2 cells was lower than that in peripheral blood, but there was no significant difference in bright CD8+CD11b+ cells (suppressor-effector T cells) between thyroid glands and peripheral blood. The percent suppression induced by Concanavalin-A in both TG-1 and TG-2 cells was significantly decreased compared with that in peripheral blood. These results suggest that impairment of suppressor cell activity and an increased number of B cells exist in thyroid glands of patients with Graves' disease compared to those in peripheral blood. It, thus, appears likely that both B cell hyperactivity and suppressor T cell dysfunction may induce excess production of autoantibodies in the thyroid glands of such patients.

Adolescent↗