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The alkaline treatment of the surface of a Ti–Cr hydrogen storage alloy was made by sticking potassium (K) metal onto the alloy block surface or by milling the alloy powder with K metal blocks instead of the use of KOH solution. This dry surface treatment was found effective to reduce the work function of electrons of the alloy surface and to ease the rate of hydrogen dissociation, resulting in an accelerated activation rate. The K atoms were found distributed in the surface oxide layer; however, X-ray photo spectroscopy (XPS) analyses in the vicinity of Fermi level suggest rather the induction of a metallic feature of the surface modified by K atoms. [Copyright &y& Elsevier]

Abstract: The effect of IL-10 antisense oligodeoxynucleotides (ODN) on the susceptibility of burned mice to intradermal (i.d.) infection of methicillin-resistant Staphylococcus aureus (MRSA) was studied. Abscesses formed and sepsis did not develop in normal mice infected i.d. with 108 CFU/mouse of MRSA. Similarly, sepsis caused by MRSA i.d. infection did not develop and abscesses formed in burned mice treated with IL-10 antisense ODN. However, all of the burned mice treated with scrambled ODN (control group) died by infectious complications stemming from MRSA i.d. infection, and an MRSA-abscess did not form in these mice. Macrophages (Mϕ) isolated from the infection site tissue of burned mice that were treated with IL-10 antisense ODN were identified as M1Mϕ, while Mϕ isolated from burned mice that were treated with scrambled ODN were shown to be M2Mϕ. MRSA-abscesses formed in burned mice inoculated with M1Mϕ, and these mice resisted a lethal dose of MRSA i.d. infection. However, an abscess did not form, and sepsis caused by MRSA i.d. infection developed in burned mice that were inoculated with M2Mϕ. These results indicate that severely burned mice treated with IL-10 antisense ODN are resistant against i.d. infection with MRSA. M1Mϕ appeared in the infection site tissues of severely burned mice that were treated with IL-10 antisense ODN may play a role on the abscess formation and inhibiting sepsis caused by MRSA i.d. infection. [Copyright &y& Elsevier]

Abstract: The susceptibility of mice to infectious complications is dramatically increased in an accompaniment with systemic inflammatory response syndrome (SIRS). Polymorphonuclear neutrophils with immunosuppressive ability (PMN-II) that appear in response to SIRS have been classified as one of the cells responsible for the increased susceptibility of mice with SIRS (SIRS mice) to sepsis induced by cecal-ligation and puncture (CLP). Since a high level of norepinephrine (NE) is demonstrated in the plasma of SIRS mice, in the present study, the role of NE on the appearance of PMN-II in SIRS mice was studied. Similar to SIRS mice, normal mice became susceptible to CLP-induced infectious complications after inoculation with NE-treated PMN. CCL2 and IL-10 (biomarkers for PMN-II) were equally produced by PMN-II prepared from SIRS mice and NE-treated PMN. However, CCL3 and IL-12 (biomarkers for immunostimulatory PMN, PMN-I) were not detected in culture fluids from either PMN preparation. These results indicate that NE mass-produced in association with SIRS development plays a role on the generation of PMN-II and the appearing PMN-II are responsible, in part, for increased susceptibility of SIRS mice to CLP-induced infectious complications. [Copyright &y& Elsevier]

Abstract: CC-chemokine ligand 2 (CCL2/monocyte chemoattractant protein 1) is known to have an important role on T helper type 2 (Th2) cell generation and described to induce interleukin (IL)-4 production by activated T cells. In the present study, an increase of CCL2 production in cultures of peripheral blood lymphocytes (PBL) from patients with severe thermal injuries was demonstrated. Severe combined immunodeficiency (SCID) mice reconstituted with PBL from healthy donors (PBL–SCID chimeras) were resistant to infection with herpes simplex virus type 1 (HSV-1). Treatment of these chimeras with recombinant human CCL2 resulted in an increased susceptibility to the same HSV-1 infection. However, human SCID mouse chimeras created by PBL depleted of natural killer T (NKT) cells (NKT- PBL–SCID chimeras) were resistant to HSV-1 infection, even though they were treated with CCL2. IL-4 was not detected in the sera of NKT- PBL–SCID chimeras treated with CCL2, while IL-4 was detected in the sera of PBL–SCID chimeras under the same CCL2 administration. NKT cells isolated from PBL were shown to be cells not responsible for CCL2-stimulated IL-4 production. However, in the presence of CCL2, IL-4 was detected in culture fluids of NKT cells co-cultured with naive T cells. This cytokine was produced in co-cultures of NKT cells pretreated with CCL2 (CCL2-NKT cells) and naive T cells. In addition, IL-4 production was demonstrated in transwell cultures of CCL2-NKT cells and naive T cells. These results suggest that NKT cells lacking IL-4 producing abilities contribute to the CCL2-associated increase in the susceptibility of thermally injured patients to HSV-1 infection through the induction of Th2 cell generation. [Copyright &y& Elsevier]

The susceptibility of thermally injured mice (TI-mice) to various infections is markedly influenced by burn-associated type 2 T cell responses, which are common with severe thermal injuries. Previously, we have reported that CC chemokine ligand 2/monocyte chemoattractant protein-I (CCL2) is produced in mice within 1 day of thermal injury, and the subsequent development of burn-associated type 2 T cell responses are triggered by this chemokine produced early after thermal injury. In this study, influence of norepinephrine (NE) on CCL2 production in mice early after thermal injury (TI) was investigated. Peripheral blood mononuclear cells (PBMC) and peritoneal macrophages (PMφ) from TI-mice produced CCL2, but the same cell preparations from normal mice did not. This chemokine was not produced by PBMC and PMφ from TI-mice previously treated with 6-hydroxydopamine (6-OHDA), which destroys sympathetic nerve termini. NE production was increased in circulation of TI-mice, and treatment of TI-mice with 6-OHDA resulted in the inhibition of NE secretion. When PBMC from normal mice were treated with NE, they acquired the ability to produce CCL2. Splenic T cells from TI-mice produced IL-4 into their culture fluids, while the cytokine was not produced by splenic T cells from TI-mice previously treated with 6-OHDA. These results indicate that NE may have an important role on early CCL2 production and the subsequent development of burn-associated type 2 T cell responses. [Copyright &y& Elsevier]

The susceptibility of thermally injured mice (TI-mice) to murine cytomegalovirus (MCMV) infection is markedly influenced by burn-associated type 2 T cell responses, which are common with severe thermal injuries. In the present study, the effect of soluble IL-4 receptor (sIL-4R) on the skin-graft-associated MCMV infection was investigated. The marked growth of MCMV was demonstrated in the salivary glands of TI-mice grafted with MCMV seropositive [MCMV sero(+)] skin. However, the growth of MCMV was not demonstrated in the salivary glands of TI-mice grafted with MCMV sero(+) skin and treated with 50 ng per mouse of sIL-4R. Compared with grafted normal mice, production of type 1 cytokines was markedly decreased when splenic T cells from TI-mice grafted with MCMV sero(+) skin were stimulated with anti-CD3 monoclonal antibody (mAb). The impaired type 1 cytokine production was recovered in cultures of splenic T cells from grafted TI-mice previously treated with sIL-4R. After grafting with MCMV sero(+) skin, the growth of MCMV was markedly inhibited in the salivary glands of severe combined immunodeficient (SCID) mice inoculated with T cells from TI-mice treated with sIL-4R. These results suggest that sIL-4R regulates the skin-graft-associated MCMV infection in TI-mice. [Copyright &y& Elsevier]

IL-12 is an inducer of type 1 T cell responses, which are essential in host defense against herpes simplex virus type 1 (HSV-1) infection. However, type 1 T cell responses are not elicited by IL-12 in thermally injured mice (TI-mice) that routinely have a predominance of burn-associated type 2 T cell responses. In our previous studies, benzoylmesaconine (BEN, an aconitine derivative extracted from heated-Aconiti tuber) induced the generation of CD4+ T cells antagonistic to type 2 T cells (BEN-CD4+ T cells). In the present study, the effects of a combination therapy using IL-12 and BEN to treat severe HSV-1 infection in TI-mice were investigated. When TI-mice were treated with either IL-12 (500 U per mouse) or BEN (1 μg/kg) alone, they did not resist HSV-1 infection. However, 60–80% of TI-mice exposed to HSV-1 survived after they received IL-12 and BEN or BEN-CD4+ T cells in combination. After stimulation with anti-CD3 mAb in vitro, IFN-γ was not produced in cultures of splenic T cells from TI-mice exposed to HSV-1 and treated with either IL-12, BEN or BEN-CD4+ T cell alone. However, IFN-γ production was induced by the mAb stimulation in the cultures of T cells from infected mice treated with IL-12 and BEN or BEN-CD4+ T cells in combination. These results suggest that the combination therapy of IL-12 (an inducer of type 1 T cell responses) and BEN (an inhibitor of type 2 T cell responses) may protect TI-mice from severe HSV-1 infection. [Copyright &y& Elsevier]