15 research outputs found
Identification of a 1.6 kb genome locus of guinea pig cytomegalovirus required for efficient viral growth in animals but not in cell culture
AbstractGuinea pig cytomegalovirus (GPCMV) provides a useful model for studies of congenital CMV infection. During characterization of the GPCMV genome sequence, we identified two types of strains in a virus stock purchased from ATCC. One of them, GPCMV/del, lacks a 1.6 kb locus that positionally corresponds to murine CMV (MCMV) M129–M133. Growth of GPCMV/del in cell culture was marginally better than that of the other strain, GPCMV/full, which harbors the 1.6 kb locus. However, in animals infected intraperitoneally with virus stocks containing both strains, GPCMV/full disseminated more efficiently than GPCMV/del, including 200-fold greater viral load in salivary glands. Viral DNA, transcripts of the immediate-early 2 gene homolog, and viral antigens were more abundant in animals infected with GPCMV/full than in those infected with GPCMV/del. Although the observed phenomena have some similarity with the growth properties of MCMV strains defective in mck-1/mck-2(M129/131) and those defective in sgg(M132), no M129–M132 homologs were found in the 1.6 kb locus. Since one of the ORFs in the locus has a weak sequence similarity with HCMV UL130, which relates to cell tropism, further studies will be required to learn the mechanism for efficient GPCMV growth in animal
Dermorphin analogueであるH-Tyr-D-Arg-Phe-β-Ala-OHおよびH-Tyr-D-Arg-Phe-β-Ala-NH_2によるcapsaicinおよびsubstance P誘発性SBL行動抑制の違いについて
Intrathecal (i.t.) administration of substance P or capsaicin elicited a characteristic behavioural response consisting of scratching, biting and licking (SBL) in mice. The behavioural response induced by substance P or capsaicin was almost completely inhibited by simultaneous i. t. injection of [D-Ala^2, MePhe^4, Gly(ol)^5] enkephalin (DAMGO), H-Tyr-D-Arg-Phe-β-Ala-OH (TAPA) or H-Tyr-D-Arg-Phe-β-Ala-NH_2 (TAPA-NH_2). Pretreatment with naloxonazine significantly antagonized inhibitory action of TAPA-NH_2 on substance Pinduced SBL behavioural response without antagonistic effect against DAMGO and TAPA, while antinociceptive effect of DAMGO, TAPA and TAPA-NH_2 was completely inhibited by the pretreatment with naloxone. TAPA-induced antinociception but not DAMGO-and TAPA-NH_2-induced antinociception on behavioural response produced by i. t. capsaicin was completely inhibited by the pretreatment with naloxonazine, whereas naloxone at a dose of 1 mg/kg s. c. completely antagonized the antinociceptive effect of i. t. co-administered TAPA, DAMGO- or TAPA-NH_2. These results led us to understanding of differential action mechanism of TAPA- and TAPA-NH_2-induced antinociception, as assayed by SBL behavioural response produced by both capsaicin and substance P
Dermorphin tetrapeptide誘導体Tyr-D-Arg-Phe-β-AlaおよびTyr-D-Arg-Phe-β-Ala-NH_2の鎮痛作用発現におけるμ1受容体の関与
Involvement of μ1-opioid receptor on the antinociception induced by dermorphin tetrapeptide analogues Try-D-Arg-Phe-β-Ala (TAPA) and Tyr-D-Arg-Phe-β-Ala-NH_2 (TAPA-NH_2) were determined in mice, using a tail-pressure test and formalin test. TAPA and TAPA-NH_2 injected i. c. v. and i. t. produced dose-dependent antinociception in both assays. In the tail-pressure test, the antinociception induced by i. c. v. and i. t. injected TAPA, but not TAPA-NH_2, was significantly attenuated by the pretreatment with naloxonazine, selective antagonist for μ1-opioid receptor. Moreover, naloxonazine also significantly attenuated the antinociception induced by i. c. v. injected TAPA, but not TAPA-NH_2 in formalin test. In contrast, the antinociception induced by both TAPA and TAPA-NH_2 given i. t. was significantly attenuated by the pretreatment with naloxonazine in formalin test. The present results suggest that TAPA and TAPA-NH_2 should be considered to be selective agonist for μ1-and μ2-opioid receptors, respectively. The C-terminal amidation may be the critical portion for TAPA-NH_2 to distinguish μ1-and μ2-opioid receptors
A Fixed Point Theorem and an Application to Bellman Operators
This study introduces a new definition of a metric that corresponds with the topology of uniform convergence on any compact set, and shows both the existence of a unique fixed point of some operator by using this metric and that the iteration of such an operator results in convergence to this fixed point. We demonstrate that this result can be applied to Bellman operators in many situations involving economic dynamics
Endomorphin analogues containing D-Pro(2) discriminate different μ-opioid receptor mediated antinociception in mice
The antagonistic actions of D-Pro(2)-endomorphins on inhibition of the paw withdrawal response by endomorphins were studied in mice. D-Pro(2)-endomorphin-1 and D-Pro(2)-endomorphin-2, injected intrathecally (i.t.), had no significant effect on the nociceptive thermal threshold alone. When D-Pro(2)-endomorphin-1 (0.05–0.1 pmol) was injected simultaneously with i.t. endomorphin-1 (5.0 nmol) or endomorphin-2 (5.0 nmol), antinociception induced by endomoprhin-1 was reduced significantly, whereas endomorphin-2-induced antinociception was not affected by D-Pro(2)-endomorphin-1. Antinociception induced by i.t. endomorphin-2 (5.0 nmol) was reduced significantly by its analogue, D-Pro(2)-endomorphin-2 (100 pmol), but not by D-Pro(2)-endomorphin-1. D-Pro(2)-endomorphin-1. D-Pro(2)-endomorphin-1 also antagonized the antinociceptive effect of i.t. DAMGO, a μ-opioid receptor agonist, whereas D-Pro(2)-endomorphin-2 failed to reduce the effect of DAMGO. These results suggest that endomorphin analogues containing D-Pro(2) are able to discriminate the antinociceptive actions of μ(1)- and μ(2)-opioid receptor agonists at the spinal cord level
Super Carbonate Apatite-miR-497a-5p Complex Is a Promising Therapeutic Option against Inflammatory Bowel Disease
The incidence of inflammatory bowel disease (IBD) is increasing worldwide. It is reported that TGF-β/Smad signal pathway is inactivated in patients with Crohn’s disease by overexpression of Smad 7. With expectation of multiple molecular targeting by microRNAs (miRNAs), we currently attempted to identify certain miRNAs that activate TGF-β/Smad signal pathway and aimed to prove in vivo therapeutic efficacy in mouse model. Through Smad binding element (SBE) reporter assays, we focused on miR-497a-5p. This miRNA is common between mouse and human species and enhanced the activity of TGF-β/Smad signal pathway, decreased Smad 7 and/or increased phosphorylated Smad 3 expression in non-tumor cell line HEK293, colorectal cancer cell line HCT116 and mouse macrophage J774a.1 cells. MiR-497a-5p also suppressed the production of inflammatory cytokines TNF-α, IL-12p40, a subunit of IL-23, and IL-6 when J774a.1 cells were stimulated by lipopolysaccharides (LPS). In a long-term therapeutic model for mouse dextran sodium sulfate (DSS)-induced colitis, systemic delivery of miR-497a-5p load on super carbonate apatite (sCA) nanoparticle as a vehicle restored epithelial structure of the colonic mucosa and suppressed bowel inflammation compared with negative control miRNA treatment. Our data suggest that sCA-miR-497a-5p may potentially have a therapeutic ability against IBD although further investigation is essential