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1.
The Influenza A virus (IAV) is a severe respiratory pathogen. C1q is the first subcomponent of the complement system’s classical pathway. C1q is composed of 18 polypeptide chains. Each of these chains contains a collagen-like region located at the N terminus, and a C-terminal globular head region organized as a heterotrimeric structure (ghA, ghB and ghC). This study was aimed at investigating the complement activation-independent modulation by C1q and its individual recombinant globular heads against IAV infection. The interaction of C1q and its recombinant globular heads with IAV and its purified glycoproteins was examined using direct ELISA and far-Western blotting analysis. The effect of the complement proteins on IAV replication kinetics and immune modulation was assessed by qPCR. The IAV entry inhibitory properties of C1q and its recombinant globular heads were confirmed using cell binding and luciferase reporter assays. C1q bound IAV virions via HA, NA and M1 IAV proteins, and suppressed replication in H1N1, while promoting replication in H3N2-infected A549 cells. C1q treatment further triggered an anti-inflammatory response in H1N1 and pro-inflammatory response in H3N2-infected cells as evident from differential expression of TNF-α, NF-κB, IFN-α, IFN-β, IL-6, IL-12 and RANTES. Furthermore, C1q treatment was found to reduce luciferase reporter activity of MDCK cells transfected with H1N1 pseudotyped lentiviral particles, indicative of an entry inhibitory role of C1q against infectivity of IAV. These data appear to demonstrate the complement-independent subtype specific modulation of IAV infection by locally produced C1q.  相似文献   

2.
The immune system homeostasis relies on a tight equilibrium of interconnected stimulatory and inhibitory signals. Disruption of this balance is characteristic of autoimmune diseases such as systemic lupus erythematosus (SLE). Aside from activating the classical complement pathway and enhancing pathogens and apoptotic cells phagocytosis, C1q has been recently shown to play an important role in immune modulation and tolerance by interacting with several inhibitory and stimulatory immune receptors. Due to its functional organization into collagen-like (CLR) and globular (GR) regions and its multimeric nature, C1q is able to interact simultaneously with several of these receptors and locally congregate pro- and anti-inflammatory signals, thus modulating the immune response. Leukocyte associated immunoglobulin-like (Ig-like) receptor 1 (LAIR-1), a ubiquitous collagen receptor expressed in many immune cell types, has been reported to interact with the CLR of C1q. In this study, we provide new insights into the molecular and structural determinants underlying C1q/LAIR-1 interaction. Recombinant LAIR-1 extracellular Ig-like domain was produced and tested for its interaction with C1q. A molecular dissection of C1q combined with competition assays reveals that LAIR-1 interacts with C1q’s CLR through a binding site close but different from the one of its associated C1r2s2 proteases tetramer. On the other side, we identified LAIR-1 residues involved in C1q interaction by site-directed mutational analysis. All together, these results lead to propose a possible model for C1q interaction with LAIR-1 and will contribute to the fundamental understanding of C1q-mediated immune tolerance.  相似文献   

3.
Otolin-1 is a scaffold protein of otoliths and otoconia, calcium carbonate biominerals from the inner ear. It contains a gC1q domain responsible for trimerization and binding of Ca2+. Knowledge of a structure–function relationship of gC1q domain of otolin-1 is crucial for understanding the biology of balance sensing. Here, we show how natural variants alter the structure of gC1q otolin-1 and how Ca2+ are able to revert some effects of the mutations. We discovered that natural substitutions: R339S, R342W and R402P negatively affect the stability of apo-gC1q otolin-1, and that Q426R has a stabilizing effect. In the presence of Ca2+, R342W and Q426R were stabilized at higher Ca2+ concentrations than the wild-type form, and R402P was completely insensitive to Ca2+. The mutations affected the self-association of gC1q otolin-1 by inducing detrimental aggregation (R342W) or disabling the trimerization (R402P) of the protein. Our results indicate that the natural variants of gC1q otolin-1 may have a potential to cause pathological changes in otoconia and otoconial membrane, which could affect sensing of balance and increase the probability of occurrence of benign paroxysmal positional vertigo (BPPV).  相似文献   

4.
邢丽贞  安莹 《净水技术》2007,26(2):53-56
对多孔型悬浮生物陶粒的物理性质及应用于曝气生物滤池在再生水处理中的应用效果进行了系统研究,并与纤维束滤池进行了运行效果比较。结果表明:多孔型悬浮生物陶粒具有挂膜快、生物亲和性好、孔隙率高、比表面积大等优点;用于再生水处理时,出水COD_G和NH_4~ -N值分别在20mg/L和10mg/L以下,处理效果优于纤维束滤池。  相似文献   

5.
Immunoglobulin G (IgG) adopts a modular multidomain structure that mediates antigen recognition and effector functions, such as complement-dependent cytotoxicity. IgG molecules are self-assembled into a hexameric ring on antigen-containing membranes, recruiting the complement component C1q. In order to provide deeper insights into the initial step of the complement pathway, we report a high-speed atomic force microscopy study for the quantitative visualization of the interaction between mouse IgG and the C1 complex composed of C1q, C1r, and C1s. The results showed that the C1q in the C1 complex is restricted regarding internal motion, and that it has a stronger binding affinity for on-membrane IgG2b assemblages than C1q alone, presumably because of the lower conformational entropy loss upon binding. Furthermore, we visualized a 1:1 stoichiometric interaction between C1/C1q and an IgG2a variant that lacks the entire CH1 domain in the absence of an antigen. In addition to the canonical C1q-binding site on Fc, their interactions are mediated through a secondary site on the CL domain that is cryptic in the presence of the CH1 domain. Our findings offer clues for novel-modality therapeutic antibodies.  相似文献   

6.
崔建方 《煤化工》2011,39(4):9-12
介绍了C1化学路线合成乙二醇的各种方法,其中直接法为合成气一步合成乙二醇,而间接法则包括甲醇法、甲醛法、草酸酯法等,并对各种方法的工艺技术特点进行了评述。重点介绍了国内煤制乙二醇技术现状和项目进展情况,并分析了中科院福建物构所开发的煤制乙二醇技术特点和指标。  相似文献   

7.
Intrauterine infection is one of the most frequent causes of miscarriage. CpG oligodeoxynucleotide (CpG ODN) can mimic intrauterine infection. CpG ODN-induced embryo-resorption was observed consistently in the NK-cell deficient non-obese diabetic (NOD) mice but not in the wild-type (WT) mice. To elucidate the molecular mechanisms of differential pregnancy outcomes, differentially expressed genes (DEGs) in the placenta and decidua basalis was revealed by RNA-Seq with CpG ODN or control ODN treatment. Common DEGs in the WT and NOD mice were enriched in antimicrobial/antibacterial humoral responses that may be activated as a primary response to bacterial infection. The susceptibility to CpG ODN-induced embryo-resorption in the NOD mice might mainly be attributed to M1 macrophage polarization and the immunodeficient status, such as the down-regulation in antigen processing and presentation, allograft rejection, and natural killer cell mediated cytotoxicity. In contrast, the WT mice with normal immune systems could activate multiple immune responses and be resistant to CpG ODN-induced embryo-resorption, such as M2 macrophage differentiation and activation regulated by complement component C1q and peroxisome proliferation-activated receptor (PPAR) signaling pathways. Collectively, this study suggests that the immunodeficient status of NOD mice and the macrophage polarization regulated by C1q and PPAR signaling might be the basis for differential pregnancy outcomes between the NOD and WT mice.  相似文献   

8.
化工原理是化工类专业大学本科阶段重要的专业基础课。作为化工原理最重要章节之一的精馏更是全书的枢纽章节。而对本章重难点之一—q值的含义的理解让很多学生觉得很费力,以致于影响了对本章内容的学习。本文从不同的角度阐述了精馏过程中q值的意义及各物理意义之间的关系,旨在帮助学生了解清楚q值的含义和掌握好精馏这一章节的内容。  相似文献   

9.
浅谈3C1B涂装技术在塑料件涂装中的应用   总被引:1,自引:0,他引:1  
3C1B涂装技术指底漆、色漆和罩光清漆三涂层湿态连续涂装后一起进行烘干的涂装方式。介绍此方式应用于塑料件涂装的技术难点和解决方法  相似文献   

10.
煤化工及相关C1化学的发展   总被引:1,自引:0,他引:1  
雍永祜 《煤化工》2005,33(6):1-4
中国缺油少气,煤炭占能源消费的70%,21世纪煤炭利用向能源与化工相结合的多联产方向发展。简述了近年来煤气化、焦化、煤制甲醇等煤化工相关技术进展。探讨了当前煤化工发展中的若干困惑:煤炭资源的保证;炼焦生产的自律;甲醇燃料是否应该大力推广;甲醇生产是否过热等。介绍了从甲醇出发值得注目的C1化学技术,并重点分析了醋酸行业的现状及发展趋势。  相似文献   

11.
传统水性漆在国内的运用已较成熟,但是水性3C1B在国内的应用还属于起步阶段,在如今VOC的排放不断受到限制的时代里,水性3C1B的发展呈现了极为良好的前景,不仅降低了能耗,而且完全符合国际流行的4E(经济、环保、高效、性能卓越)原则。  相似文献   

12.
车身3C1B涂装工艺的应用研究   总被引:1,自引:0,他引:1  
以溶剂型银灰金属漆为例,通过与3C2B工艺的涂层性能对比,探讨整车3C1B工艺的可行性。  相似文献   

13.
Classically activated M1 macrophages reprogram their metabolism towards enhanced glycolysis to obtain energy and produce pro-inflammatory cytokines after activation by mammalian target of rapamycin complex 1 (mTORC1) and hypoxia-inducible factor (HIF)-1α. Thus, a strategy that constrains M1 polarization of macrophages via downregulation of glycolysis is essential for treating chronic inflammatory diseases. Cassiae semen has pharmacological activity against various inflammatory diseases. However, it is unclear whether specific compounds within Cassia seeds affect M1 polarization of macrophages. Here, we investigated whether Cassiaside C napthopyrone from Cassiae semen inhibits M1 polarization by downregulating glycolysis. We found that Cassiaside C reduced expression of inducible nitric oxide synthase and cyclooxygenase-2 and the phosphorylation of nuclear factor kappa B, all of which are upregulated in lipopolysaccharide (LPS)/interferon (IFN)-γ-treated Raw264.7 cells and peritoneal macrophages. Moreover, Cassiaside C-treated macrophages showed marked suppression of LPS/IFN-γ-induced HIF-1α, pyruvate dehydrogenase kinase 1, and lactate dehydrogenase A expression, along with downregulation of the phosphoinositide 3-kinases (PI3K)/AKT/mTORC1 signaling pathway. Consequently, Cassiaside C attenuated enhanced glycolysis and lactate production, but rescued diminished oxidative phosphorylation, in M1 polarized macrophages. Thus, Cassiaside C dampens M1 polarization of macrophages by downregulating glycolysis, which could be exploited as a therapeutic strategy for chronic inflammatory conditions.  相似文献   

14.
碳一化工是煤化工专业的一门主干课程。教学过程中通过调整课程体系,合理安排教学内容,采用案例式教学方法,使碳一化工的专业知识有条理地融于讲授的过程中,达到了丰富教学内容、激发学生学习兴趣、提高学生知识综合运用能力的目的,对培养优秀的应用型人才起到了积极的作用。  相似文献   

15.
围绕3C1B涂装技术在塑料件涂装中的应用进行了探讨,介绍了塑料件快干底漆的选用以及3C1B涂装工艺流程,并对涂层性能进行了介绍和评价。  相似文献   

16.
In our previous study, we identified an association of high expression of c3orf1, also known as TIMMDC1 (translocase of inner mitochondrial membrane domain-containing protein 1), with metastatic characteristics in lung carcinoma cells. To investigate the preliminary function and mechanism of this mitochondrial protein, we depleted C3orf1 expression by introducing siRNA into 95D lung carcinoma cells. We demonstrated that C3orf1 depletion significantly suppressed 95D cell growth and migration. We confirmed C3orf1 localization in the inner mitochondrial membrane and showed that mitochondrial viability, membrane potential, and ATPase activity were remarkably reduced upon depletion of C3orf1. Microarray data indicated that genes involved in regulation of cell death, migration, and cell-cycle arrest were significantly altered after C3orf1 depletion for 48 h. The expression of genes involved in focal adhesion, ECM-receptor interaction, and p53-signaling pathways were notably altered. Furthermore, cell-cycle arrest genes such as CCNG2 and PTEN as well as genes involved in cell migration inhibition, such as TIMP3 and COL3A1, were upregulated after C3orf1 depletion in 95D cells. Concurrently, expression of the migration-promoting gene NUPR1 was markedly reduced, as confirmed by real-time PCR. We conclude that C3orf1 is critical for mitochondrial function, migration, and proliferation in 95D lung carcinoma cells. Depletion of C3orf1 inhibited cell migration and cell proliferation in association with upregulation of genes involved in cell-cycle arrest and cell migration inhibition. These results suggest that C3orf1 (TIMMDC1) may be a viable treatment target for lung carcinoma, and that further study of the role of this protein in lung carcinoma pathogenesis is justified.  相似文献   

17.
Background: Hereditary angioedema (HAE) is a rare, genetic disease caused by the decreased level or function of the C1 inhibitor. The primary mediator of symptoms in HAE is bradykinin acting through its two receptors, namely receptors 1 (BR1) and 2 (BR2). Although BR2 is well characterized, the role of BR1 remains unclear. Objective: To study the role of bradykinin receptors 1 (BR1) in the etiopathogenesis of HAE. Methods: A total of 70 individuals, 40 patients with HAE, and 30 healthy subjects were recruited to the study. HAE was diagnosed in accordance with the international guideline. The level of bradykinin receptors was determined in populations of CD3+, CD4+, CD8+, and CD14++CD16, CD14++CD16+ monocytes. In addition, the level of disease activity-specific markers was measured. Results: There were statistically significant differences in the subpopulation of lymphocytes and monocytes between patients with HAE compared to healthy subjects. The level of BR1 and BR2 on PBMCs was comparable in healthy subjects and HAE patients during remission with significant overexpression of both receptors, triggered by HAE attack. Moreover, a significant increase in TNF-alpha and IL-1 plasma levels was observed among HAE patients. Conclusions: BR1 expression may play an important role in the pathomechanism of HAE.  相似文献   

18.
本文对还原黄G的各种颜料化工艺进行了综述,并评价了今后的发展趋势,有39篇参考文献,  相似文献   

19.
The complement system is involved in promoting secondary injury after traumatic brain injury (TBI), but the roles of the classical and lectin pathways leading to complement activation need to be clarified. To this end, we aimed to determine the ability of the brain to activate the synthesis of classical and lectin pathway initiators in response to TBI and to examine their expression in primary microglial cell cultures. We have modeled TBI in mice by controlled cortical impact (CCI), a clinically relevant experimental model. Using Real-time quantitative polymerase chain reaction (RT-qPCR) we analyzed the expression of initiators of classical the complement component 1q, 1r and 1s (C1q, C1r, and C1s) and lectin (mannose binding lectin A, mannose binding lectin C, collectin 11, ficolin A, and ficolin B) complement pathways and other cellular markers in four brain areas (cortex, striatum, thalamus and hippocampus) of mice exposed to CCI from 24 h and up to 5 weeks. In all murine ipsilateral brain structures assessed, we detected long-lasting, time- and area-dependent significant increases in the mRNA levels of all classical (C1q, C1s, C1r) and some lectin (collectin 11, ficolin A, ficolin B) initiator molecules after TBI. In parallel, we observed significantly enhanced expression of cellular markers for neutrophils (Cd177), T cells (Cd8), astrocytes (glial fibrillary acidic protein—GFAP), microglia/macrophages (allograft inflammatory factor 1—IBA-1), and microglia (transmembrane protein 119—TMEM119); moreover, we detected astrocytes (GFAP) and microglia/macrophages (IBA-1) protein level strong upregulation in all analyzed brain areas. Further, the results obtained in primary microglial cell cultures suggested that these cells may be largely responsible for the biosynthesis of classical pathway initiators. However, microglia are unlikely to be responsible for the production of the lectin pathway initiators. Immunofluorescence analysis confirmed that at the site of brain injury, the C1q is localized in microglia/macrophages and neurons but not in astroglial cells. In sum, the brain strongly reacts to TBI by activating the local synthesis of classical and lectin complement pathway activators. Thus, the brain responds to TBI with a strong, widespread and persistent upregulation of complement components, the targeting of which may provide protection in TBI.  相似文献   

20.
Disruptive neuronal migration during early brain development causes severe brain malformation. Characterized by mislocalization of cortical neurons, this condition is a result of the loss of function of migration regulating genes. One known neuronal migration disorder is lissencephaly (LIS), which is caused by deletions or mutations of the LIS1 (PAFAH1B1) gene that has been implicated in regulating the microtubule motor protein cytoplasmic dynein. Although this class of diseases has recently received considerable attention, the roles of non-synonymous polymorphisms (nsSNPs) in LIS1 on lissencephaly progression remain elusive. Therefore, the present study employed combined bioinformatics and molecular modeling approach to identify potential damaging nsSNPs in the LIS1 gene and provide atomic insight into their roles in LIS1 loss of function. Using this approach, we identified three high-risk nsSNPs, including rs121434486 (F31S), rs587784254 (W55R), and rs757993270 (W55L) in the LIS1 gene, which are located on the N-terminal domain of LIS1. Molecular dynamics simulation highlighted that all variants decreased helical conformation, increased the intermonomeric distance, and thus disrupted intermonomeric contacts in the LIS1 dimer. Furthermore, the presence of variants also caused a loss of positive electrostatic potential and reduced dimer binding potential. Since self-dimerization is an essential aspect of LIS1 to recruit interacting partners, thus these variants are associated with the loss of LIS1 functions. As a corollary, these findings may further provide critical insights on the roles of LIS1 variants in brain malformation.  相似文献   

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