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Moxibustion is a technique used in traditional oriental medicine, the aim of which is to cure and/or prevent illness by activating a person's ability for self‐healing. In this study, we assessed how moxibustion would affect the immune system and whether it would augment protective immunity. Mice were treated with moxibustion at Zusanli (ST36) acupoints; we analyzed mortality and cytokine activity in sera after infection with herpes simplex virus type 1 (HSV‐1), and cytokine gene expression in the skin and the spleen without a virus challenge. Our study demonstrates that pretreatment of BALB/c mice with moxibustion resulted in a marked increase in the survival rate after infection with lethal doses of HSV‐1, and elevated serum levels of IL‐1β and IFN‐γ on days 1 and 6 post‐infection with HSV‐1. Semi‐quantitative RT‐PCR assay showed that moxibustion treatment augmented the expression of IL‐1α, IL‐1β, IL‐6, universal‐IFN‐α, MIP‐1α, and TNF‐α mRNA in the skin, and IL‐1α, IL‐1β, IL‐12p40, IL‐15, u‐IFN‐α, MIP‐1α, and TNF‐α mRNA in the spleen. Moreover, moxibustion induces augmentation of natural killer cell activity. Collectively, our study demonstrates that moxibustion activates protective responses against HSV‐1 infection through the activation of cytokine production including IFN, and of NK cells.  相似文献   
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A series of 5,5-dimethylthiohydantoin derivatives were synthesized and evaluated for androgen receptor pure antagonistic activities for the treatment of castration-resistant prostate cancer. Since CH4933468, which we reported previously, had a problem with agonist metabolites, novel thiohydantoin derivatives were identified by applying two strategies. One was the replacement of the alkylsulfonamide moiety by a phenylsulfonamide to avoid the production of agonist metabolites. The other was the replacement of the phenyl ring with a pyridine ring to improve in vivo potency and reduce hERG affinity. Pharmacological assays indicated that CH5137291 (17b) was a potent AR pure antagonist which did not produce the agonist metabolite. Moreover, CH5137291 completely inhibited in vivo tumor growth of LNCaP-BC2, a castration-resistant prostate cancer model.  相似文献   
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A selective κ-opioid receptor agonist might act as a powerful analgesic without the side effects of μ-opioid receptor-selective drugs such as morphine. The eight classes of known κ-opioid receptor agonists have different chemical structures, making it difficult to construct a pharmacophore model that takes them all into account. Here we propose a new three-dimensional pharmacophore model that encompasses the κ-activities of all classes, which utilizes conformational sampling of agonists by high-temperature molecular dynamics and pharmacophore extraction through a series of molecular superpositions.  相似文献   
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In the process of tissue injury and repair, epithelial cells rapidly migrate and form epithelial sheets. Vinexin is a cytoplasmic molecule of the integrin-containing cell adhesion complex localized at focal contacts in vitro. Here, we investigated the roles of vinexin in keratinocyte migration in vitro and wound healing in vivo. Vinexin knockdown using siRNA delayed migration of both HaCaT human keratinocytes and A431 epidermoid carcinoma cells in scratch assay but did not affect cell proliferation. Induction of cell migration by scratching the confluent monolayer culture of these cells activated both EGFR and ERK, and their inhibitors AG1478 and U0126 substantially suppressed scratch-induced keratinocyte migration. Vinexin knockdown in these cells inhibited the scratch-induced activation of EGFR, but not that of ERK, suggesting that vinexin promotes cell migration via activation of EGFR. We further generated vinexin (−/−) mice and isolated their keratinocytes. They similarly showed slow migration in scratch assay. Furthermore, vinexin (−/−) mice exhibited a delay in cutaneous wound healing in both the back skin and tail without affecting the proliferation of keratinocytes. Together, these results strongly suggest a crucial role of vinexin in keratinocyte migration in vitro and cutaneous wound healing in vivo.  相似文献   
227.
Oxidative stress plays a pivotal role in chronic heart failure. SIRT1, an NAD+-dependent histone/protein deacetylase, promotes cell survival under oxidative stress when it is expressed in the nucleus. However, adult cardiomyocytes predominantly express SIRT1 in the cytoplasm, and its function has not been elucidated. The purpose of this study was to investigate the functional role of SIRT1 in the heart and the potential use of SIRT1 in therapy for heart failure. We investigated the subcellular localization of SIRT1 in cardiomyocytes and its impact on cell survival. SIRT1 accumulated in the nucleus of cardiomyocytes in the failing hearts of TO-2 hamsters, postmyocardial infarction rats, and a dilated cardiomyopathy patient but not in control healthy hearts. Nuclear but not cytoplasmic SIRT1-induced manganese superoxide dismutase (Mn-SOD), which was further enhanced by resveratrol, and increased the resistance of C2C12 myoblasts to oxidative stress. Resveratrol''s enhancement of Mn-SOD levels depended on the level of nuclear SIRT1, and it suppressed the cell death induced by antimycin A or angiotensin II. The cell-protective effects of nuclear SIRT1 or resveratrol were canceled by the Mn-SOD small interfering RNA or SIRT1 small interfering RNA. The oral administration of resveratrol to TO-2 hamsters increased Mn-SOD levels in cardiomyocytes, suppressed fibrosis, preserved cardiac function, and significantly improved survival. Thus, Mn-SOD induced by resveratrol via nuclear SIRT1 reduced oxidative stress and participated in cardiomyocyte protection. SIRT1 activators such as resveratrol could be novel therapeutic tools for the treatment of chronic heart failure.  相似文献   
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Mottled Tohoku (Atp7a(Mo-Tohm) or Mo(Tohm)) is an X-linked mutation with mottled pigmentation in heterozygous (Mo(Tohm)/+) females and is embryonic lethal at E11 in hemizygous (Mo(Tohm)/Y) males. Copper levels were low in the brain and high in the intestine of Mo(Tohm) mice. Two congenic strains with ICR or C57BL/6 (B6) background were produced for genetic and phenotypic analyses and revealed that Mo(Tohm)/+ females with ICR background survived until adulthood, while most with B6 background died within 2 days after birth. The Mo(Tohm)/Y males with both backgrounds died at around E11. Massive hemorrhage was shown in the yolk sac cavity with irregular attachment between the mesoderm and the endothelial cells of blood vessels in the embryos at E10.5, suggesting that this irregular attachment causes embryonic lethality. The Mo(Tohm) mutant had a 1440-bp deletion between intron 22 and exon 23 of the Atp7a gene. Mo(Tohm)/Y males with the wild-type Atp7a cDNA transgene were rescued from embryonic lethality, confirming that the Mo(Tohm) mutant is caused by the defect in the Atp7a gene. This mutant mouse is the most severe model of human Menkes disease in mottled mice established to date and one of the useful models for understanding the gene function of Menkes disease.  相似文献   
230.
The effectiveness of two inducible nitric oxide synthase (iNOS) inhibitors on allergic airway inflammation was investigated under different administration schedules. Rats sensitized to ovalbumin (OVA) were exposed to OVA for 3 consecutive days. Both iNOS inhibitors showed markedly different effects between two pretreatment schedules: pretreatment before each of three OVA exposures S1 and before the third exposure alone S2. S1 pretreatment resulted in higher pulmonary resistance than triple OVA alone. This potentiation was associated with increased eosinophil infiltration and malondialdehyde levels in the lungs, which were suppressed by superoxide dismutases (SODs) but not by methylprednisolone. However, the S2 administration of both iNOS inhibitors completely suppressed the airway response. Administration by schedule S1 completely suppressed plasma nitrite and nitrate levels, but that by S2 caused only a slight suppression. The triple OVA exposures resulted in the upregulation of iNOS in alveolar macrophages and arginase activity, Mn- and Cu/Zn-SOD expression, and nitrotyrosine and lipid peroxide deposition in the airway. However, inhibitors administered by schedule S1 suppressed this upregulation, but further potentiated nitrotyrosine, which in turn was inhibited by SOD. Although iNOS inhibitors may be beneficial for asthma, repeated administration may be detrimental because of extensive reduction of NO and downregulation of SOD.  相似文献   
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