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Biomedical subjects

M Ohtsuka

Publications and source records attributed to M Ohtsuka.

At least 199 records · Page 11Linked to original sources
PubMed1986

Analysis of bronchoalveolar lavage cells and fluids in patients with hypersensitivity pneumonitis: possible role of chemotactic factors in the pathogenesis of disease.

The current study concerns immunological mechanisms involved in the pathogenesis of hypersensitivity pneumonitis (HP) by an analysis of the cells and chemotactic factors (CF) obtained by bronchoalveolar lavage (BAL). Nine patients at an acute stage (HP acute, 8 summer type and 1 pigeon breeder's lung) and 4 patients at a quiescent stage (HP quiescent, 3 summer type and 1 pigeon breeder's lung) were included. The results indicate that: CF for polymorphonuclear cells (PMN) in HP acute were significantly more potent than in HP quiescent; CF for mononuclear cells were not significantly different in the groups; the percentage of lymphocytes in HP acute was significantly greater even though HP quiescent revealed greater percentages of lymphocytes as compared to normal controls; determination of T cell subsets employing OKT antibodies revealed the ratio of OKT8+ cells to OKT4+ cells in HP acute was significantly higher than in HP quiescent, and chemotaxis for PMN was marginally correlated with the percentage of OKT8+ cells at the acute stage of disease.

Albumins↗
PubMed1986

Complement-mediated lysis of K562 human leukemic cells by antibodies to phosphotyrosine and identification of cell surface proteins phosphorylated on tyrosine.

Intact K562 human leukemic cells showed bright membrane immunofluorescence after staining with monoclonal antibody to O-phosphotyrosine (PTyr). Up to 60% of the cells were lysed with mouse, rabbit, or human antibodies to PTyr by a complement-mediated mechanism. A new method has been developed for identifying proteins that have PTyr residues on the outside of cell membrane, and at least two species of PTyr-containing proteins with the molecular weights of 45,000 and 36,000 were identified as the most probable candidates of the antigens responsible for the membrane fluorescence and cell lysis.

Antibodies, Monoclonal↗
PubMed1985

Measurement of cutaneous blood flow by clearance of hydrogen gas generated by electrolysis.

In an attempt to assess the reliability of a method for measurement of local blood flow-namely, the clearance of electrochemically generated hydrogen gas-a series of experiments were conducted using the skin and skin flap in rats and rabbits. The results showed high accuracy in obtained values, good reproducibility in the repeated measurements, and consistency with the values obtained by the hydrogen gas inhalation method. Histological examination revealed only minimal damage to the tissue resulting from the measurement. Using this method, blood flow was measured at different sites on the flap in rats. The critical point of blood flow as measured by this method was thoroughly consistent with the dye distance as well as with the survival length. No injurious effects of the measurement procedure on flap survival were noticed. The present study suggests a wide potential application of this method in plastic surgery because of its high reliability and because no radioactivity is involved.

Animals↗
PubMed1985

Anti-O-phosphotyrosine antibodies in human sera.

Antibodies reactive with O-phosphotyrosine (PTYR) were detected in 60 out of 621 inpatients, with high frequencies in hematologic and lung malignancies, hepatic diseases, cerebrovascular diseases, and autoimmune diseases. Affinity-purified antibodies proved capable of recognizing PTYR-containing proteins in a human carcinoma cell line, A431, both by immunofluorescent staining and by immunoaffinity chromatography, but had no detectable affinity for phosphorylated serine or threonine, or for the nucleotides tested. In these respects, the antibodies observed in human sera were indistinguishable from anti-PTYR antibodies raised experimentally in rabbits or mice.

Adolescent↗
PubMed1985

The hypotensive effect of 2-(5-chloro-2-phenoxyanilino)-2-imidazoline (FR35447).

The hypotensive effect of FR35447 was comparable to that of prazosin and was more potent than that of hydralazine, but its duration of action was shorter. Repeated administration of FR35447 or prazosin to hypertensive rats for 5 consecutive days induced no significant difference in the intensity or duration of the hypotensive effect. In contrast, marked tachyphylaxis to hydralazine or phentolamine was observed. FR35447 as well as prazosin induced only a transient increase in cardiac output in anesthetized dogs, whereas hydralazine induced a longlasting increase. This difference may contribute to no development of tolerance to FR35447 or prazosin. FR35447 decreased the pressor response to noradrenaline, but not that to angiotensin II or vasopressin in pithed rats, which indicates that FR35447 is an alpha-adrenoceptor antagonist. FR35447 has some selectivity for alpha 2-adrenoceptors, but the selectivity was far less than that of yohimbine. Since FR35447 induced only slight hypotension following intracerebroventricular injection in anesthetized cats, the hypotensive effect of the drug does not appear to be mediated through the central nervous system. Whereas prazosin induced a dose-dependent increase in blood glucose in rats, FR35447 showed no significant effect.

Animals↗
PubMed1985

Immunofluorescent staining of human leukemic cells with monoclonal antibody to phosphotyrosine.

Peripheral blood cells and bone marrow cells from patients with various types of leukemia, but not those from healthy persons, were brightly immunofluorescent (IF) after staining with monoclonal antibody reactive to O-phosphotyrosine. All the IF-positive cells observed in peripheral blood were judged to be leukemic in morphology, and the IF-positive cells comprised 40-90% of total leukemic cells present in blood. Similar bright fluorescence was observed in the K562 human leukemic cell line. The results raise the possibility that leukemic cells can be distinguished from normal hematologic cells by their increased contents of phosphorylated tyrosine residues.

Antibodies, Monoclonal↗
PubMed1985

Increase of phosphotyrosine-containing proteins in human carcinomas.

Immunofluorescent (IF) staining with monoclonal antibody to O-phosphotyrosine (PTYR) has shown that a variety of human carcinomas (liver, esophagus, stomach, lung, colon and breast) have increased amounts of PTYR-containing proteins (PTYR-proteins), which are localized in cytoplasmic regions and nucleolus-like structures of the carcinoma cells. PTYR-proteins were isolated from carcinomas of the liver, stomach and esophagus, and also from normal regions of these organs by immunoaffinity chromatography with polyclonal antibodies to PTYR. They were then labeled with 125I and analyzed by gel electrophoresis. Twenty-eight species of PTYR-proteins in a molecular weight range from 310,000 to 23,000 were detected, of which the major 16 species were confirmed to contain 125I-labeled diiodo-O-phosphotyrosine residues. All the PTYR-proteins found in carcinomas were also present, though at much lower levels, in normal regions of the respective organs.

Carcinoma↗
PubMed1984

Preparation and characterization of antibodies to O-phosphotyrosine and their use for identification of phosphotyrosine-containing proteins.

To facilitate the identification of phosphotyrosine (P-tyr)-containing proteins, rabbit polyclonal antibodies and mouse monoclonal antibody specifically reactive to P-tyr were prepared by hyperimmunizing the animals with P-tyr-conjugated bovine serum albumin or poly-L-lysine. As determined by a solid-phase radioimmunoassay and an enzyme-linked immunosorbent assay, the antibodies reacted with P-tyr-conjugated target antigens but not with those conjugated with phosphoserine (P-ser) or phosphothreonine (P-thr). This immune reaction was strongly blocked by 2 mM P-tyr and phenylphosphate but not by P-ser or P-thr. The antibodies were capable of isolating, as the major P-tyr-containing components, a 170kd protein (most likely the EGF receptor) from EGF-stimulated, 32P-labelled A431 cells, and 130kd and 60kd proteins from Rous sarcoma virus (RSV)-transformed chick cell lysate which had been labelled in vitro with gamma-32P-ATP. Immunofluorescent staining of RSV-transformed cells and A431 cells showed specific localization of P-tyr-containing proteins in the cytoplasm, plasma membrane, and nucleolus-like structures. The results demonstrated the usefulness of the antibodies for identification or isolation of P-tyr-containing proteins.

Animals↗
PubMed1984

A human nucleolar antigen (pp90) associated with cell growth and its induction by Epstein-Barr virus and human cytomegalovirus.

Immunofluorescent staining of HeLa cells with rabbit antiserum raised against isolated HeLa cell nucleoli showed bright nucleolar fluorescence. Immunoprecipitation of nuclear extracts obtained from HeLa cells labelled with 35S-methionine or 32P-orthophosphate followed by gel electrophoresis of the precipitate revealed a major band of 90 kd. This antigen, called pp90, was judged to be responsible for the nucleolar fluorescence. Serine residues were predominantly phosphorylated in pp90. Similar nucleolar fluorescence was observed commonly in human cells derived from malignant tumors including acute lymphatic leukemia, adult T-cell leukemia, hepatitis B virus-associated hepatoma, adenocarcinoma, and in 5 lymphoid cells derived from Burkitt lymphoma but not in normal human lymphocytes or liver cells. In immunoprecipitation, 32P-labelled pp90 was commonly detected as the major component in all of those cells which showed nucleolar fluorescence. Resting human embryo lung (HEL) cells were negative for both nucleolar fluorescence and pp90 in immunoprecipitation, but turned positive when stimulated to grow, suggesting the involvement of pp90 in cell growth. Antigen pp90 was also induced in human lymphocytes and HEL cells by infection with Epstein-Barr virus in human cytomegalovirus, respectively, which are known to induce cell DNA synthesis in early stages of infection. A cross-reacting nucleolar antigen was detected in 2 monkey cells but not in 3 rodent cells tested.

Adult↗
PubMed1984

[Chronic dacryocystitis cured by probing of the duct].

A seven-year-old case with chronic dacryocystitis resulting from congenital obstruction of the nasolacrimal duct was cured not by a dacryocystorhinostomy but by probing of the duct. Our results show that even in case of planned dacryocystorhinostomy, probing of the duct should be performed at least once.

Child↗
PubMed1984

Ontogenetic appearance of somatostatin-containing nerve terminals in the median eminence of rats.

The development of immunoreactive (ir) somatostatin-containing nerve terminals in the rat median eminence (ME) has been examined electron-microscopically. Nerve fibers containing ir particles scattered throughout the axoplasm are first seen in the external layer of the ME on day 18.5 of gestation, and, on day 21.5 appear to terminate on the basement membrane of the perivascular space of the portal vessels. After birth, the fiber terminals contain several membrane-limited granules, which are labeled with ir PAP particles. Ultrathin, Epon-embedded sections of ME, treated by the protein A gold-labeling method for somatostatin, demonstrate positively labeled granules in the nerve fibers in the postnatal ME, but in the prenatal tissue, no specific gold-labeling is found. These findings show that, in the external layer of the ME, somatostatin storing occurs in the granules in the axonal terminals after birth.

Aging↗
PubMed1984

Lymphoid interstitial pneumonia associated with depressed cellular immunity and polyclonal gammopathy.

This report describes a case of lymphoid interstitial pneumonia (LIP) associated with polyclonal gammopathy and selective depression of cellular immunity. Enhanced humoral immunity is suggested because the patient exhibited increased levels of circulating immunoglobulin (chiefly IgG) and a positive test reaction for rheumatoid factor. When first examined, the patient displayed depressed cellular immunity in that the results of his skin test were negative to dinitrochlorobenzene and phytohemagglutinin (PHA), his peripheral lymphocytes responded suboptimally to PHA, and he had decreased numbers of circulating T cells. When examined 6 yr later, the patient was again hypergammaglobulinemic, but he had regained some of his cellular immune function. Eight years after the patient was initially seen, he showed further improvement in cellular immune function. Analysis of bronchoalveolar lavage cells showed that the patient had a normal proportion of OKT4+ (inducer/helper) cells, but a reduced number of OKT8+ (suppressor/cytotoxic) cells. Thus, his improvement may have been associated with a correction of an imbalance of immunoregulatory T cells. Furthermore, because the disease was active on initial examination but less active after the second evaluation, malfunction of his cellular immune functions may have been involved in the pathogenesis of LIP.

Humans↗
PubMed1983

Electronmicroscopic study of somatostatin-containing neurons in rat arcuate nucleus with special reference to neuronal regulation.

After an intraventricular administration of colchicine, the arcuate nucleus of rat hypothalamus was examined light and electron microscopically by pre-embedding immunohistochemistry for somatostatin. The arcuate nucleus exhibited numerous immunoreactive cell bodies and dense networks of immunoreactive fibers. The fibers appeared to surround immunonegative cell bodies. The immunoreactive cell bodies were multipolar in shape and projected immunoreactive processes to some extent. The immunoreactive cell bodies and fibers received synaptic contacts by immunonegative fiber terminals containing a large number of synaptic clear vesicles. Similarly, immunoreactive somatostatin fibers appeared to terminate upon other immunonegative cell bodies and fibers. The immunoreactive presynaptic terminals contain several labeled granules and numerous synaptic vesicles. In close proximity to these immunolabeled terminals, non-labeled presynaptic terminals were also observed upon the immunonegative cell bodies and fibers. This suggests that in the arcuate nucleus neurons regulated by somatostatin neurons are also under the control of other types of neurons.

Animals↗