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991.
van de Veerdonk FL Stoeckman AK Wu G Boeckermann AN Azam T Netea MG Joosten LA van der Meer JW Hao R Kalabokis V Dinarello CA 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(8):3001-3005
The functional role of IL-1 family member 10, recently renamed IL-38, remains unknown. In the present study we aimed to elucidate the biological function of IL-38 and to identify its receptor. Heat-killed Candida albicans was used to stimulate memory T-lymphocyte cytokine production in freshly obtained human peripheral blood mononuclear cells from healthy subjects. The addition of recombinant IL-38 (152 amino acids) inhibited the production of T-cell cytokines IL-22 (37% decrease) and IL-17 (39% decrease). The reduction in IL-22 and IL-17 caused by IL-38 was similar to that caused by the naturally occurring IL-36 receptor antagonist (IL-36Ra) in the same peripheral blood mononuclear cells cultures. IL-8 production induced by IL-36γ was reduced by IL-38 (42% decrease) and also was reduced by IL-36Ra (73% decrease). When human blood monocyte-derived dendritic cells were used, IL-38 as well as IL-36Ra increased LPS-induced IL-6 by twofold. We screened immobilized extracellular domains of each member of the IL-1 receptor family, including the IL-36 receptor (also known as "IL-1 receptor-related protein 2") and observed that IL-38 bound only to the IL-36 receptor, as did IL-36Ra. The dose-response suppression of IL-38 as well as that of IL-36Ra of Candida-induced IL-22 and IL-17 was not that of the classic IL-1 receptor antagonist (anakinra), because low concentrations were optimal for inhibiting IL-22 production, whereas higher concentrations modestly increased IL-22. These data provide evidence that IL-38 binds to the IL-36R, as does IL-36Ra, and that IL-38 and IL-36Ra have similar biological effects on immune cells by engaging the IL-36 receptor. 相似文献
992.
Fabbri M Paone A Calore F Galli R Gaudio E Santhanam R Lovat F Fadda P Mao C Nuovo GJ Zanesi N Crawford M Ozer GH Wernicke D Alder H Caligiuri MA Nana-Sinkam P Perrotti D Croce CM 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(31):E2110-E2116
MicroRNAs (miRNAs) are small noncoding RNAs, 19-24 nucleotides in length, that regulate gene expression and are expressed aberrantly in most types of cancer. MiRNAs also have been detected in the blood of cancer patients and can serve as circulating biomarkers. It has been shown that secreted miRNAs within exosomes can be transferred from cell to cell and can regulate gene expression in the receiving cells by canonical binding to their target messenger RNAs. Here we show that tumor-secreted miR-21 and miR-29a also can function by another mechanism, by binding as ligands to receptors of the Toll-like receptor (TLR) family, murine TLR7 and human TLR8, in immune cells, triggering a TLR-mediated prometastatic inflammatory response that ultimately may lead to tumor growth and metastasis. Thus, by acting as paracrine agonists of TLRs, secreted miRNAs are key regulators of the tumor microenvironment. This mechanism of action of miRNAs is implicated in tumor-immune system communication and is important in tumor growth and spread, thus representing a possible target for cancer treatment. 相似文献
993.
994.
J Oral Pathol Med (2012) 41 : 500–504 Background: Atrophic glossitis (AG) is considered to be a marker of nutritional deficiency. In this study, we evaluated whether there was an intimate association of the deficiency of hemoglobin, iron, vitamin B12 or folic acid, high blood homocysteine level, and serum gastric parietal cell antibody (GPCA) positivity with AG. Methods: The blood hemoglobin, iron, vitamin B12, folic acid, and homocysteine concentrations and the serum GPCA level in 176 AG patients were measured and compared with the corresponding levels in 176 age‐ and sex‐matched healthy control subjects. Results: We found that 39 (22.2%), 47 (26.7%), 13 (7.4%), and 3 (1.7%) AG patients had deficiencies of Hb (men < 13 g/dl, women < 12 g/dl), iron (<60 μg/dl), vitamin B12 (<200 pg/ml), and folic acid (<4 ng/ml), respectively. Moreover, 38 (21.6%) AG patients had abnormally high blood homocysteine level, and 47 (26.7%) AG patients had serum GPCA positivity. AG patients had a significantly higher frequency of Hb, iron, or vitamin B12 deficiency, of abnormally elevated blood homocysteine level, or of serum GPCA positivity than healthy control subjects (all P‐values = 0.000). However, no significant difference in frequency of folic acid deficiency was found between AG patients and healthy control subjects. Conclusion: We conclude that there is a significant association of deficiency of hemoglobin, iron and vitamin B12, abnormally high blood homocysteine level, and serum GPCA positivity with AG. 相似文献
995.
南京市12岁儿童第一恒磨牙龋病影响因素分析 总被引:1,自引:0,他引:1
目的:探讨南京市12岁儿童第一恒磨牙患龋情况及其影响因素。方法:采用随机抽样的方法抽取南京市12岁儿童660名,进行口腔健康检查和口腔问卷调查。数据采用SPSS 13.0统计软件处理,分析12岁儿童第一恒磨牙患龋率与影响因素的关系。结果:南京市12岁儿童第一恒磨牙患龋率31.1%,男生患龋率29.6%,女生患龋率32.2%。Logistic回归分析显示,饮用碳酸饮料和第一恒磨牙是否做过窝沟封闭这两个因素与12岁儿童第一恒磨牙患龋有显著关联(OR>1)。结论:碳酸饮料是龋病的危险因素,做窝沟封闭可以降低患龋的危险性。 相似文献
996.
目的:观察牙龈卟啉单胞菌(Porphyromonas gingivalis,Pg)上清液对体外培养的兔血管平滑肌细胞分泌IL-1β、IL-6的影响。方法:组织块法培养兔腹主动脉血管平滑肌细胞,并对其细胞来源进行鉴定。用4.3×106 CFU/mL的Pg上清液刺激细胞12、24、48 h后,通过ELISA检测IL-1β、IL-6的水平;同时用RT-PCR检测其mRNA表达的情况。结果:Pg上清液刺激24 h和48 h时能促进血管平滑肌细胞分泌IL-6,分别与同一时间点的对照组相比差异均有统计学意义(P<0.05),而且24 h时,IL-6表达最强,而IL-1β的表达最低,明显低于相同时间的对照组和其他时间点的实验组(P<0.05)。RT-PCR检测显示,4.3×106 CFU/mL的Pg上清刺激血管平滑细胞12、24、48 h后细胞内均有IL-1β、IL-6的基因表达,在24 h时,血管平滑肌细胞的IL-1β基因表达减少,而IL-6基因表达增加。结论:Pg上清液可促进细胞合成和分泌IL-6,在动脉粥样硬化的发生发展过程中可能发挥一定作用。 相似文献
997.
赵玉雪 《中国实用口腔科杂志》2012,5(6):379-382
白细胞介素-1(interleukin-1,IL-1)是人体内非常活跃的促炎细胞因子,可刺激内皮细胞和白细胞释放一系列炎性介质,由此引发局部组织或全身的的炎症.牙周病是发生在牙龈、牙周膜和牙槽骨等牙齿支持组织的一种慢性破坏性疾病,其病理机制与牙周局部炎症有密切的联系.本文就IL-1的分化、功能及其与牙周病的关系做一综述. 相似文献
998.
Bouki KP Katsafados MG Chatzopoulos DN Psychari SN Toutouzas KP Charalampopoulos AF Sakkali EN Koudouri AA Liakos GK Apostolou TS 《International journal of cardiology》2012,154(3):287-292
Background
OCT with its unique image resolution is the ideal method to detect culprit lesion characteristics in different clinical presentations. The identification of inflammatory markers related to plaque characteristics may be of clinical importance.Methods
Thirty-two patients with acute coronary syndromes (ACS) and fourteen patients with stable angina pectoris (SAP) were enrolled in this study. Culprit lesion morphology was assessed by optical coherence tomography (OCT) in patients with ACS and SAP. The possible relations between serum levels of high sensitivity-C reactive protein (hs-CRP) and interleukin-18 (IL-18) with plaque characteristics were investigated in those patients.Results
Plaque rupture and thin-cap fibroatheroma (TCFA) were detected more frequently in ACS patients compared with SAP patients, (78.6% vs. 14.3%, p < 0.001, 92.9% vs. 14.3%, p < 0.001, respectively). Higher levels of serum hs-CRP and IL-18 were found in patients with plaque rupture vs. those with no plaque rupture (median value: 19.2 mg/L vs. 1.6 mg/L, p < 0.001 and 219.5 pg/ml vs. 127.5 pg/ml, p = 0.001 respectively), and TCFA vs. those without TCFA (median value: 15.2 mg/L vs. 1.6 mg/L, p = 0.004 and 209.0 pg/ml vs.153.2 pg/ml, p = 0.03 respectively). Serum hs-CRP was the only independent predictor of plaque rupture (p = 0.02, odds ratio 1.1, 95% confidence interval 1.0 to 1.2). A cut-off value of hs-CRP > 4.5 mg/L could detect ruptured plaque with a sensitivity of 91.7% and a specificity of 77.8%.Conclusions
OCT detected plaque rupture and TCFA more frequent in ACS patients compared with SAP. Elevated hs-CRP and IL-18 were positively related to plaque instability and rupture. 相似文献999.
Sheriff S Kadeer N Joshi R Friend LA James JH Balasubramaniam A 《Molecular and cellular endocrinology》2012,351(2):286-295
Although ghrelin and GHRP-2 have been shown to inhibit skeletal muscle proteolysis in rats with burn injury, the effects of des-acyl ghrelin (DAG) have not been reported. In this paper, we demonstrate that continuous 24h administration of DAG attenuated burn-induced EDL muscle proteolysis, and normalized elevated TNFα mRNA. Combined treatment of cultured C2C12 myotubes with TNFα and IFN-γ (TNF+IFN) inhibited protein synthesis and increased protein breakdown; DAG abolished both effects. PI3 kinase inhibition by LY294002 and mTOR inhibition by rapamycin blocked the reversal of the anti-anabolic effects of TNF+IFN-treated myotubes by DAG. DAG also reversed or attenuated the TNF+IFN-induced reduction in phosphorylation of Akt, FOXO1, 4E-BP-1, and GSK-3β in myotubes. Furthermore, DAG attenuated the atrophy signal, phospho-NF-κB, and the mRNA expression of MAFbx and MuRF1, upregulated by TNF+IFN in C2C12 myotubes. We conclude that DAG reduces muscle cachexia produced by injury and proinflammatory cytokines, and that DAG or DAG-based compounds may be useful in treating wasting disorders. 相似文献
1000.
The hinge region in androgen receptor control 总被引:2,自引:0,他引:2
Clinckemalie L Vanderschueren D Boonen S Claessens F 《Molecular and cellular endocrinology》2012,358(1):1-8
The region between the DNA-binding domain and the ligand-binding domain of nuclear receptors is termed the hinge region. Although this flexible linker is poorly conserved, diverse functions have been ascribed to it. For the androgen receptor (AR), the hinge region and in particular the (629)RKLKKL(634) motif, plays a central role in controlling AR activity, not only because it acts as the main part of the nuclear translocation signal, but also because it regulates the transactivation potential and intranuclear mobility of the receptor. It is also a target site for acetylation, ubiquitylation and methylation. The interplay between these different modifications as well as the phosphorylation at serine 650 will be discussed here. The hinge also has an important function in AR binding to classical versus selective androgen response elements. In addition, the number of coactivators/corepressors that might act via interaction with the hinge region is still growing. The importance of the hinge region is further illustrated by the different somatic mutations described in patients with androgen insensitivity syndrome and prostate cancer. In conclusion, the hinge region serves as an integrator for signals coming from different pathways that provide feedback to the control of AR activity. 相似文献