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C Nishimura

Publications and source records attributed to C Nishimura.

At least 91 records · Page 5Linked to original sources
PubMed1989

Relative abundance of aldose reductase mRNA in rat lens undergoing development of osmotic cataracts.

Aldose reductase (AR) messenger RNA concentration was determined in normal rat lens and in lens from rats fed a 50% galactose diet over a period of 20 days. The AR mRNA was detected by using a previously described AR cDNA clone. The relative concentration of the AR mRNA was estimated by cpm of 35S-UTP labeled antisense RNA hybridized to dot-blots prepared from cytosols isolated from single lens, decapsulated lens (cortex) and its respective capsule (epithelia). The results demonstrated that the concentration of the AR mRNA in the epithelium doubled over the 20 day period. Correspondingly, an increase in the concentration of the DNA was also observed, suggesting that the increase in epithelial cytosolic mRNA might be partially due to the increase in the number of epithelial cells occurring in lens undergoing cataractogenesis. The increase in AR mRNA in the epithelia was gradual, and it doubled by day 12 on galactose, while the increase in DNA was rapid and reached an optimum level by about day 4. By day 4 the cortex AR mRNA concentration increased, then rapidly decreased to insignificant levels by day 20. Changes in AR mRNA and in DNA following a high influx of galactose in the lens might suggest a heightened gene response to changes in the cellular environment for the lens epithelium.

Aldehyde Reductase↗
PubMed1988

Antiherpes activity of the immunomodulator OK-432, a streptococcal preparation, in immunosuppressed mice.

The antiviral activity of OK-432, an antitumor agent originating from Streptococcal preparations, against herpes simplex virus type 2 (HSV-2) was investigated in mice immunosuppressed by cyclophosphamide (CY). Intraperitoneal administration of OK-432 to mice 1 day after treatment with 200 mg CY/kg prevented death due to HSV-2 encephalitis in a dose-dependent manner. When the immunosuppressed mice were given OK-432 prior to HSV-2 infection, both by the intraperitoneal route, virus growth in the peritoneal cavity was significantly suppressed. Following with OK-432, the number of macrophages in immunosuppressed mice was increased to a significantly greater extent than the numbers of lymphocytes and polymorphonuclear leukocytes. The intrinsic antiviral activity of macrophages against HSV-2 as well as the natural killer (NK) activity against YAC-1 target cells was significantly enhanced by OK-432 in immunosuppressed mice.

Animals↗
PubMed1988

Enhancement of nonspecific resistance to viral infection by chemically synthesized lipid A-subunit analogs with different backbone structures and acyl groups.

Protection against vaccinia virus infection and induction of interferon (IFN) were investigated in Propionibacterium acnes-primed mice following treatment with chemically synthesized lipid A-subunit derivatives. The antiviral activity was based on the reduction of numbers of tail lesions in mice injected intravenously with the test compounds 1 day before virus infection. GLA-27, a 4-O-phosphono-D-glucosamine carrying 3-O-tetradecanoyl (C14) and N-3-tetradecanoyloxytetradecanoyl [C14-O-(C14)] groups, offered significant antiviral activity. Chemical modifications at the C1 position of GLA-27, e.g. phosphorylation, replacement of OH by an SH, did not cause a significant change in antiviral activity. GLA-57 carrying an N-3-dodecanoyloxytetradecanoyl group showed stronger activity than GLA-27, but GLA-58 carrying an N-3-hexadecanoyloxytetradecanoyl group did not exhibit significant activity. GLA-59 carrying 3-O-3-hydroxytetradecanoyl and N-C14-O-(C14) groups was more active than GLA-27 and GLA-57. GLA-60 possessing the same fatty acid substituents as GLA-59 but in the reversed order was the most active of all compounds tested. This suggests that the nature and position of the acyl substituents are important for achieving the antiviral effects. The (R) isomers of GLA-59 and GLA-60 possessed stronger IFN-inducing activity than the (S) isomers, but no significant difference in antiviral activity was seen between the isomers.

Animals↗
PubMed1988

Characterization of mRNA and genes for aldose reductase in rat.

Aldose reductase (AR; E.C. 1. 1. 1. 21) has been implicated in a variety of diabetic complications. To investigate the expression of this enzyme in target tissues susceptible to such complications, mRNA encoding AR was characterized by Northern blot hybridization in various tissues and cultured cell preparations. The size of mRNA for AR (approximately 1500 bases) was in good agreement with the size determined by sequence analysis. A cDNA probe for AR from rat lens hybridized to the same size species of RNA isolated from cultured dog lens epithelial cells, cultured human retinal capillary pericytes (mural cells), and Y 79 human retinoblastoma cells. In rat tissues, a substantial amount of mRNA was expressed not only in lens, but also in retina, sciatic nerve and kidney medulla. AR mRNA seemed to be less abundant in rat skeletal muscle and brain, and was scarcely present in liver. Furthermore, Southern blot analysis of rat genomic DNA indicated that there are multiple sequences related to that for AR, probably indicating the existence of a multi-gene family.

Aldehyde Reductase↗
PubMed1988

Immunopharmacological activities of chemically synthesized lipid A-subunit analogue GLA-27 combined with muramyl dipeptide via spacers of different carbon chain length.

A lipid A-subunit analogue GLA-27, a 4-O-phosphono-D-glucosamine derivative carrying 3-O-tetradecanoyl and N-3-tetradecanoyloxytetradecanoyl groups, exhibited significant biological activities but no detectable pyrogenicity or local Shwarzman activity. In order to synthesize compounds combining GLA-27 with muramyl dipeptide (MDP), the OH group at the C6 position of GLA-27 was first succinylated. A compound which combined a succinylated GLA-27 (GLA-101) with 1-deoxy N-acetyl-muramyl-L-alanyl-D-isoglutamine methyl ester (1-deoxy MDP) via spacers of different carbon chain lengths of 5, 11 and 15, termed GLA-105, GLA-106 and GLA-107, respectively, and their biological activities were investigated. Intraperitoneal administration of combined preparations with spacers, GLA-105 and GLA-107, induced much higher phagocytic activity in peritoneal macrophages than GLA-27, GLA-101 and 1-deoxy MDP. The activity of GLA-106 did not increase by the combination. In induction of natural killer (NK) activity in peritoneal cells, GLA-105 and GLA-107 were significantly more active than 1-deoxy MDP but only comparable with GLA-27. GLA-101 showed stronger NK activity than GLA-27. The activity of GLA-106 was stronger than 1-deoxy MDP but weaker than GLA-27, GLA-105 and GLA-107. Mitogenic, interferon-inducing and tumor necrosis factor-inducing activities decreased by combining GLA-101 with 1-deoxy MDP. GLA-101, GLA-105 and GLA-107 strongly inhibited the formation of lesions on the tail of mice infected with Vaccinia virus. The activity was almost equivalent to that of GLA-27.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1988

Activation of murine peritoneal macrophages by intraperitoneal administration of a traditional Chinese herbal medicine, xiao-chai-hu-tang (Japanese name: shosaiko-to).

Macrophage activation by a traditional Chinese herbal medicine, xiao-chai-hu-tang (Japanese name: shosaiko-to), was investigated. Intraperitoneal (i.p.) administration of shosaiko-to into (BALB/c x DBA/2)F1 mice resulted in marked activation of macrophages with respect to phagocytic and lysosomal enzyme activities (acid phosphatase and N-acetyl-beta-D-glucosaminidase) compared with the control. The maximal responses were induced by an i.p. injection of 3 mg shosaiko-to 4 days previously. Enhanced activities induced by shosaiko-to were also seen in C3H/HeJ mice, which is a non-responder strain to bacterial lipopolysaccharide (LPS). Significant macrophage accumulation in the peritoneal cavity and increased lysosomal enzyme activities were observed in mice injected with shosaiko-to. Shosaiko-to exhibited significant cytostasis-inducing activity. In addition, the administration of shosaiko-to led to a moderate expression of Ia antigen on the surface of peritoneal macrophages. These results suggest that shosaiko-to is a potent macrophage activator.

Animals↗
PubMed1988

Antitumor and antimicrobial activities of lipid A-subunit analogue GLA-27.

Activities for enhancing nonspecific host resistance against microbial infections and growth inhibition against tumors by a lipid A-subunit analogue GLA-27 were investigated. GLA-27, a 4-O-phosphono-D-glucosamine derivative with 2-N-3-tetradecanoyloxytetradecanoyl and 3-O-tetradecanoyl group, inhibited significantly the growth of solid-type tumors RL male 1 lymphoma and Meth A fibrosarcoma. In the case of RL male 1 lymphoma, 2.5 micrograms of GLA-27 was needed to exhibit the activity, while for Meth A fibrosarcoma, 250 micrograms of GLA-27 was needed. On the other hand, tail lesions induced by intravenous inoculation with vaccinia virus were effectively suppressed in mice injected with 1 microgram of GLA-27 1 day before the viral injection. The antiviral activity of GLA-27 was 100 times higher than that of MDP by ED50. GLA-27 also showed nonspecific protective activity against Pseudomonas aeruginosa infection at a dose of 30 micrograms/mouse, although the activity was far less than that induced by lipid A. GLA-27 did not exhibit toxic activities such as pyrogenicity and Shwartzman reaction.

Adjuvants, Immunologic↗
PubMed1987

Aldose reductase and p-crystallin belong to the same protein superfamily as aldehyde reductase.

Aldose reductase (EC 1.1.1.21) has been implicated in a variety of diabetic complications. Here we present the first primary sequence data for the rat lens enzyme, obtained by amino acid and cDNA analysis. We have found structural similarities with another NADPH-dependent oxidoreductase: human liver aldehyde reductase (EC 1.1.1.2). The identity between these two enzymes is 50%. Both enzymes share approx. 40-50% homology with p-crystallin, a major lens protein present only in the frog, Rana pipiens. We propose that aldose reductase, aldehyde reductase and p-crystallin are members of a superfamily of related proteins.

Alcohol Dehydrogenase↗