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Increasing evidence suggests that human epidermal melanocytes play an important role in the skin immune system; however, a role of their pigmentation in immune and inflammatory responses is poorly examined. In the study, the expression of Toll‐like receptor 4 (TLR4) and inflammatory cytokines and chemokines by cultured normal melanocytes derived from lightly and darkly pigmented skin was investigated after cell stimulation with lipopolysaccharide (LPS). The basal TLR4 mRNA level in heavily pigmented cells was higher as compared to their lightly pigmented counterparts. Melanocyte exposure to LPS upregulated the expression of TLR4 mRNA and enhanced the DNA‐binding activity of NF‐κB p50 and p65. We found substantial differences in the LPS‐stimulated expression of numerous genes encoding inflammatory cytokines and chemokines between the cells with various melanin contents. In lightly pigmented melanocytes, the most significantly upregulated genes were nicotinamide phosphoribosyltransferase (NAMPT/visfatin), the chemokines CCL2 and CCL20, and IL6, while the genes for CXCL12, IL‐16 and the chemokine receptor CCR4 were the most significantly upregulated in heavily pigmented cells. Moreover, the lightly pigmented melanocytes secreted much more NAMPT, CCL2 and IL‐6. The results of our study suggest modulatory effect of melanogenesis on the immune properties of normal epidermal melanocytes. 相似文献
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AIM: The aim of this study was to quantify the flow-mediated dilatation (FMD) of brachial artery in asymptomatic members of families with familial combined hyperlipidemia (FCH) and to determine the relation between FMD and risk factors accompanying FCH. We also investigated the association between FMD and the intima-media thickness (IMT) of the common carotid artery. METHODS: Eighty-two members of 29 FCH families were divided into two groups: probands and hyperlipidemic first-degree relatives (HL) (n=47) and normolipidemic first-degree relatives (NL) (n=35). The control (C) groups, C-HL (n=20) and C-NL (n=20), consisted of sex- and age-matched healthy individuals. FMD was assessed in the brachial artery by measuring the change in brachial artery diameter in response to reactive hyperemia. RESULTS: Both hyperlipidemic subjects and their NL had significantly lower FMD (3.4+/-3% vs 6.3+/-2.8%, P<0.001, 5.2+/-2.3% vs 7.8+/-2.8%, P<0.01, respectively) compared to controls. In multivariate backward stepwise regression analysis, FMD in members of FCH families was independently associated with sex (P<0.001), age (P<0.01), C-peptide (P<0.05) and borderline with glycemia (P=0.052). FMD correlated inversely with IMT in all subjects of FCH families and in hyperlipidemic members. In multivariate backward stepwise regression analysis this relation remained independent (P<0.001, P<0.01, respectively). CONCLUSIONS: Members of FCH families showed impaired FMD, which was independently associated with markers of insulin resistance. FMD and IMT were independently associated in hyperlipidemic, but not in normolipidemic members of FCH families. 相似文献
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The temporal bones from fetuses with known autosomal trisomy syndromes were examined histopathologically after spontaneous or induced abortions. Fetal ages dated from the 17th to the 24th week of pregnancy. In all, 17 temporal bones from nine fetuses were studied and included seven cases of Down's syndrome and two of Edwards' syndrome. Temporal bones from fetuses with Down's syndrome had more abnormalities of the external and middle ears than of the inner ear. The bones from the fetuses with Edwards' syndrome showed abnormalities of the external or middle ear and retarded development of the inner ear (failed ossification of the otic capsule and unformed organ of Corti). 相似文献
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Virus-like particles were found in the brain and salivary glands of Dermacentor reticulatus ticks double infected with Coxiella burnetii and Rickettsiella phytoseiuli. The particles were spherical (diameter of about 70 nm) and consisted of an electron-dense inner core and a dense external coat. 相似文献
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The metabolic consequences of the uncoupling effect of phenylhydrazonopropanedinitrile and others uncouplers of oxidative phosphorylation on Ehrlich ascites carcinoma (EAC) cells were investigated. Upon application of uncouplers in concentrations stimulating the respiration of EAC cells the accelerate glucose uptake and lactate production was observed. The maximal glycolysis stimulation was fourfold in relation to control at the given experimental conditions. Simultaneously the degree of conversion of glucose on lactate was increased. The acceleration of glycolysis was accompanied by stimulation of 14C-labeled adenine and valine incorporation indicating the increased rate of biosynthetic processes. The prolongation of uncoupler action time and application of their higher concentrations cause the inhibition of glycolysis and biosynthetic processes which is evoked with nonspecific effects of the compounds. 相似文献
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A Tomsíková 《Ceskoslovenská epidemiologie, mikrobiologie, imunologie》1992,41(1):45-63
The author analyzes factors influencing the occurrence of mycoses in AIDS-patients with different stages of the disease. The clinical picture, the diagnosis and sources of common as well as uncommon mycoses accompanying AIDS are given in detail. Candidosis, cryptococcosis, histoplasmosis and dermatomycosis complicate AIDS frequently most. The course of all mycoses in AIDS patients is quite different from the course of the same mycoses complicating other diseases. 相似文献