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991.
992.
Yi Pang Lu-Tai Tien Hobart Zhu Juying Shen Camilla F. Wright Tembra K. Jones Samir A. Mamoon Abhay J. Bhatt Zhengwei Cai Lir-Wan Fan 《International journal of molecular sciences》2015,16(4):8635-8654
Our previous study showed that a single lipopolysaccharide (LPS) treatment to neonatal rats could induce a long-lasting neuroinflammatory response and dopaminergic system injury late in life. This is evidenced by a sustained activation of microglia and elevated interleukin-1β (IL-1β) levels, as well as reduced tyrosine hydroxylase (TH) expression in the substantia nigra (SN) of P70 rat brain. The object of the current study was to test whether co-administration of IL-1 receptor antagonist (IL-1ra) protects against LPS-induced neurological dysfunction later in life. LPS (1 mg/kg) with or without IL-1ra (0.1 mg/kg), or sterile saline was injected intracerebrally into postnatal day 5 (P5) Sprague-Dawley male rat pups. Motor behavioral tests were carried out from P7 to P70 with subsequent examination of brain injury. Our results showed that neonatal administration of IL-1ra significantly attenuated LPS-induced motor behavioral deficits, loss of TH immunoreactive neurons, as well as microglia activation in the SN of P70 rats. These data suggest that IL-1β may play a pivotal role in mediating a chronic neuroinflammation status by a single LPS exposure in early postnatal life, and blockading IL-1β might be a novel approach to protect the dopaminergic system against perinatal infection/inflammation exposure. 相似文献
993.
Lechun Song Jinshe Chen Yinghui Bian Lijun Zhu Yulu Zhou Yuzhi Xiang Daohong Xia 《Journal of Porous Materials》2015,22(2):379-385
Cu-incorporated MCM-41 was prepared by the direct synthesis method. The Cu-incorporated MCM-41 was then organically functionalized by grafting of organosilanes followed by the complexation of copper ions. The results of powder X-ray diffraction, Fourier transform infrared, and temperature-programmed reduction suggest the incorporation of Cu into the framework of MCM-41 during the direct synthesis process. The mesostructure of prepared samples is preserved after functionalization. The sulfur capacities for tert-butyl mercaptan, dimethyl sulfide, and dimethyl disulfide decrease in the same order (40)Cu–M > (40)Cu–M–N–Cu. The (40)Cu–M synthesized through the direct synthesis method also shows better desulfurization performance than M–Cu prepared by the incipient wetness impregnation method. This is attributed to the incorporated Cu species in the framework and well-dispersed CuO species of (40)Cu–M. 相似文献
994.
Wen Wang Na He Chenchen Feng Victor Liu Luyi Zhang Fei Wang Jiaping He Tengfang Zhu Shuyang Wang Weiwei Qiao Suke Li Guangdong Zhou Li Zhang Chengxiang Dai Wei Cao 《International journal of molecular sciences》2015,16(6):12076-12091
Mesenchymal stem cells (MSCs) are known to have the potential for articular cartilage regeneration, and are suggested for the treatment of osteoarthritis (OA). Here, we investigated whether intra-articular injection of xenogeneic human adipose-derived mesenchymal progenitor cells (haMPCs) promoted articular cartilage repair in rabbit OA model and engrafted into rabbit articular cartilage. The haMPCs were cultured in vitro, and phenotypes and differentiation characteristics of cells were evaluated. OA was induced surgically by anterior cruciate ligament transection (ACLT) and medical meniscectomy of knee joints. At six weeks following surgery, hyaluronic acid (HA) or haMPCs was injected into the knee joints, the contralateral knee served as normal control. All animals were sacrificed at the 16th week post-surgery. Assessments were carried out by macroscopic examination, hematoxylin/eosin (HE) and Safranin-O/Fast green stainings and immunohistochemistry. The data showed that haMPC treatment promoted cartilage repair. Signals of human mitochondrial can be directly detected in haMPC treated cartilage. The haMPCs expressed human leukocyte antigen I (HLA-I) but not HLA-II-DR in vivo. These results suggest that intra-articular injection of haMPCs promotes regeneration of articular cartilage in rabbit OA model, and support the notion that MPCs are transplantable between HLA-incompatible individuals. 相似文献
995.
996.
Zhizhi Hu Guangchang Pei Pengge Wang Juan Yang Fengmin Zhu Yujiao Guo Meng Wang Ying Yao Rui Zeng Wenhui Liao Gang Xu 《International journal of molecular sciences》2015,16(9):22621-22635
Biliverdin reductase A is an enzyme, with serine/threonine/tyrosine kinase activation, converting biliverdin (BV) to bilirubin (BR) in heme degradation pathway. It has been reported to have anti-inflammatory and antioxidant effect in monocytes and human glioblastoma. However, the function of BVRA in polarized macrophage was unknown. This study aimed to investigate the effect of BVRA on macrophage activation and polarization in injured renal microenvironment. Classically activated macrophages (M1macrophages) and alternative activation of macrophages (M2 macrophages) polarization of murine bone marrow derived macrophage was induced by GM-CSF and M-CSF. M1 polarization was associated with a significant down-regulation of BVRA and Interleukin-10 (IL-10), and increased secretion of TNF-α. We also found IL-10 expression was increased in BVRA over-expressed macrophages, while it decreased in BVRA knockdown macrophages. In contrast, BVRA over-expressed or knockdown macrophages had no effect on TNF-α expression level, indicating BVRA mediated IL-10 expression in macrophages. Furthermore, we observed in macrophages infected with recombinant adenoviruses BVRA gene, which BVRA over-expressed enhanced both INOS and ARG-1 mRNA expression, resulting in a specific macrophage phenotype. Through in vivo study, we found BVRA positive macrophages largely existed in mice renal ischemia perfusion injury. With the treatment of the regular cytokines GM-CSF, M-CSF or LPS, excreted in the injured renal microenvironment, IL-10 secretion was significantly increased in BVRA over-expressed macrophages. In conclusion, the BVRA positive macrophage is a source of anti-inflammatory cytokine IL-10 in injured kidney, which may provide a potential target for treatment of kidney disease. 相似文献
997.
Inside Cover: Critical Intermediates Reveal New Biosynthetic Events in the Enigmatic Colibactin Pathway (ChemBioChem 12/2015) 下载免费PDF全文
998.
Yuan Wang Baoyong Zhu 《Journal of Inorganic and Organometallic Polymers and Materials》2015,25(4):948-954
Two new Zn(II) coordination polymers based on the tridentate ligand 4,6-di(1H-imidazol-1-yl)-1,3,5-triazin-2-ol (Hdit), namely, {[Zn(dit)2(H2O)2]·4H2O}n (1) and [Zn(dit)(CH3COO)]n (2), have been successfully constructed by varying the metal salts. Compound 1 shows 1D zigzag chain structure, and compound 2 is a 3D binodal (3,5)-connected architecture with {42·66·82}{42·6} topology. The photoluminescent spectra indicate that at room temperature, compounds 1 and 2 emit violet and blue luminescence, respectively. 相似文献
999.
在换热器制造中,管与管板的焊接质量决定了换热器本身的质量优劣和使用寿命,而管与管板焊接质量的好坏主要取决于管与管板的接头形式。内孔焊焊接就是为改善端面焊接的缺点而采用的较为先进的工艺方法,是一个全焊透结构。用内孔焊结构代替传统的管与管板角焊缝结构,是提高换热管与管板连接焊缝抗腐蚀能力和间隙腐蚀能力的根本途径。本文结合实践中的经验,阐述了内孔焊的接头形式、工艺顺序、焊接工艺参数及焊接过程中注意的问题等。 相似文献
1000.