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Biomedical subjects

M Iijima

Publications and source records attributed to M Iijima.

At least 217 records · Page 12Linked to original sources
PubMed1985

Separation of enkephalin-degrading enzymes from longitudinal muscle layer of bovine small intestine. Enzyme inhibition by arphamenine A.

The enkephalin-degrading enzymes, such as aminopeptidase, dipeptidyl aminopeptidase, dipeptidyl carboxypeptidase and carboxypeptidase, were purified partially by DEAE-cellulose column chromatography, using longitudinal muscle from bovine small intestine. These enzyme were inhibited by EDTA and o-phenanthroline. Several protease inhibitors of microbial origin, and synthetic compounds, were tested for their abilities to inhibit these enkephalin-degrading enzymes. Among them, arphamenine A, a new potent inhibitor for aminopeptidase B, was shown to be a useful compound in inhibiting all of the enkephalin-degrading enzymes in small intestine.

Aminopeptidases↗
PubMed1985

Temporal analysis of rat liver injury following potentiation of carbon tetrachloride hepatotoxicity with ketonic or ketogenic compounds.

The administration of some ketonic or ketogenic compounds prior to a challenging dose of CCl4 potentiates the hepatic damage induced by this haloalkane. However, nothing is known about the recovery from the liver injury in these cases of chemically induced potentiation. To investigate this problem, we performed a temporal analysis of the hepatotoxic response of male Sprague-Dawley rats to CCl4 following a single pretreatment (p.o.) with: n-hexane, 2-hexanone, 2,5-hexanedione (15 mmol/kg in corn oil), isopropanol, acetone (33 and 34 mmol/kg in water, respectively); or the vehicle alone (10 ml/kg). They received, 18 h later, an i.p. injection of CCl4 (0.1, 0.75 or 1.0 ml/kg) and were killed 24-120 h later. Liver damage was assessed biochemically (ALT, OCT) and morphologically. A good correlation between biochemical and morphological results was observed. The ketonic or ketogenic compounds studied potentiated the liver injury produced by 0.1 ml/kg CCl4. Relative ranking orders regarding severity of maximal hepatic damage induced and time needed for complete recovery of liver injury were established; time of recovery was dependent on the maximal severity of the lesion, regardless of the potentiation. The results show that the temporal evolution of CCl4-induced liver injury is not markedly influenced by the administration of ketonic or ketogenic compounds as pretreatments, but rather depends on the severity of the maximal damage induced by the overall treatment.

Administration, Oral↗
PubMed1985

The role of Langerhans cells in antigen presentation.

Epidermal Langerhans cells are dendritic bone marrow-derived cells which synthesize and express Ia antigens. During the past decade, in vitro studies have demonstrated that they play a critical role in the induction of many types of T-cell responses. Specifically, Langerhans cells are effective antigen-presenting cells in allogeneic and antigen specific proliferative and cytotoxic T-cell responses. This paper reviews these functions and suggests areas of future investigations into the mechanisms involved in T-cell activation by Langerhans cells.

Antibodies, Monoclonal↗
PubMed1985

Characteristic of antinociceptive effect of a tetrapeptide, Asn-Ala-Gly-Ala (NAGA).

The characteristic of the antinociceptive effect of a tetrapeptide, Asn-Ala-Gly-Ala (NAGA), was examined. Intracisternal (i.cist.) administration of NAGA to mice produced dose-dependent and long-lasting antinociceptive effect as evaluated by the hot plate and tail flick methods. NAGA-induced antinociception was reversed by naloxone (2 mg/kg), reserpine (2 mg/kg X 2 d) and alpha-methyl-p-tyrosine (100 mg/kg). NAGA (10 microM) did not significantly affect the actions of opioid peptides on the electrically evoked twitches of the myenteric plexus-longitudinal muscle strips from the guinea-pig esophagus and strips of the mouse vas deferens. NAGA-induced antinociception was scarcely affected by p-chlorophenylalanine (PCPA, 300 mg/kg X 2 d) and methysergide (2 mg/kg). From the above results, it was suggested that the antinociceptive effect of NAGA may involve the participation of endogenous opioid peptides and endogenous catecholamines.

Analgesics↗
PubMed1984

Mechanism of hepatic megamitochondria formation by ammonia derivatives. Correlation between structure of chemicals and their ability to induce the formation of megamitochondria.

Correlation between the chemical structure and the ability to induce hepatic megamitochondria formation was studied by feeding mice and rats diets containing a wide spectrum of ammonia derivatives. Ammonia derivatives with electron-releasing groups, such as hydrazine, phenylhydrazine, hydroxylamine and aniline were effective in inducing megamitochondria. Ammonia derivatives with electron-withdrawing groups, such as formamide, sulfamic acid, acetamide were ineffective in inducing megamitochondria. Inducibility of ammonia derivatives with electron-releasing groups plus electron-withdrawing groups for the megamitochondria formation was dependent upon nucleophilicity of the chemical: 2,4-dinitrophenylhydrazine induced megamitochondria, while acetanilide did not induce megamitochondria. The megamitochondria formation induced by ammonia derivatives was a reversible process. Freeze-fracture studies on megamitochondria indicated that megamitochondria were formed by the fusion of adjacent mitochondria. Phosphorylating capacity of megamitochondria (hydrazine-induced megamitochondria, for example) were normal despite morphological changes. These data might suggest that the nucleophilicity of chemicals plays a key role in the induction of hepatic megamitochondria. These data might also suggest that the phenomenon is an adaptive process to changes of intracellular milieu.

Ammonia↗
PubMed1984

Biosynthesis of the internal thioester bond of the third component of complement.

C3-translational product, which was synthesized with rabbit liver mRNA in a reticulocyte lysate protein-synthesizing system, did not react with [14C]methylamine, indicating the lack of an internal thioester bond. Instead, the C3-translational product reacted with iodo[1-14C]acetamide, as determined by gel electrophoresis in the presence of sodium dodecyl sulfate after immunoprecipitation of the product, indicating the presence of a reactive thiol group. When the C3-translational product was treated with rabbit liver homogenate, the product acquired reactivity with [14C]methylamine and lost the reactivity with iodo[1-14C]acetamide. Thus, the liver homogenate seemed to contain a factor (or factors) required for the formation of an internal thioester bond. The factor was partially purified from the liver homogenate by ammonium sulfate precipitation and ion-exchange chromatography on DEAE-cellulose.

Animals↗
PubMed1984

Induction of megamitochondria in the rat liver by N-propyl alcohol and N-butyl alcohol.

Propyl alcohol and butyl alcohol had similar effects to ethyl alcohol on ultrastructure of liver mitochondria. Rats were given 32% ethyl alcohol, 32% n-propyl alcohol, and 6.9% n-butyl alcohol in drinking water for up to three months. After one month, mitochondria in hepatocytes obtained from the experimental animals became elongated, constricted or cup-shaped with scanty cristae. After two months, mitochondria in some hepatocytes became gigantic. In extreme cases, the megamitochondria exceeded 10 micron in diameter. Coupling efficiencies of hepatic mitochondria obtained from alcohol-fed animals were well preserved despite their drastic morphologic changes.

1-Butanol↗
PubMed1984

High incidence of peliosis hepatis in autopsy cases of aplastic anemia with special reference to anabolic steroid therapy.

The livers were collected from 47 autopsy cases of aplastic anemia aiming to study the correlation between the use of androgenic anabolic steroid and the formation of peliosis hepatis. Association of peliosis hepatis was found in 7 cases out of 19 cases with anabolic steroid therapy, while peliotic cavities were found only in one case out of the remaining 28 cases without anabolic steroid therapy. Out of 7 cases specified above, peliotic cavities in 5 cases were phlebectatic; phlebectatic and parenchymal types of peliotic cavities coexisted in one case, and one case was parenchymatous. Besides these cavity formations, remarkable dilatation of sinusoids often distinct at the periphery of the hepatic lobule was found in the 7 cases.

Adolescent↗
PubMed1984

A comparison of the inhibitory effects of ketotifen and disodium cromoglycate on bronchial responses to house dust, with special reference to the late asthmatic response.

Ten patients with allergic asthma were studied to compare the inhibitory effects of ketotifen and disodium cromoglycate on bronchial responses, especially the late asthmatic response, induced by house dust allergen in bronchial provocation tests. In the first study, types of bronchial response to house dust challenge were classified from peak expiratory flow rate measurements made at intervals after the test. Nine patients showed dual asthmatic response (immediate with isolated late response) and 1 patient showed isolated late asthmatic response. The tests were treated at 1-week intervals, patients having been premedicated from the night before the test with either ketotifen (3 X 2 mg oral doses) or disodium cromoglycate (3 X 40 mg by inhalation). The results showed that both drugs produced significant protection against the immediate bronchial response and that ketotifen was at least as effective as disodium cromoglycate in inhibiting the late asthmatic response.

Adolescent↗