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51.
A streptavidin derivitised macroporous monolith was developed to enable single-step capture of chemically biotinylated Moloney Murine Leukaemia Virus (MoMuLV) from crude, unclarified cell culture supernatant. Monoliths were prepared by aqueous cryopolymerisation of acrylamide with N,N'-methylene-bis (acrylamide) and glycidyl methacrylate (Arvidsson et al. [2003] J Chrom A 986:275-290). Streptavidin was immobilised to the epoxy functionalised monoliths. Particulate-containing cell culture supernatant was passed through the monolith without preclarification of the feedstock and adsorption capacities of 2 x 10(5) cfu/ml of adsorbent were demonstrated (cf. Fractogel streptavidin, at 3.9 x 10(5) cfu/ml of adsorbent). The specific titre of the recovered fraction was increased by 425-fold; however, recoveries of less than 8% were achieved. Adsorption of nonbiotinylated MoMuLV on the streptavidin-coated monolith was not observed. 相似文献
52.
Paul L. Black Hamblin Phillips Henry R. Tribble Robin Pennington Mark schneider James E. Talmadge 《Cancer immunology, immunotherapy : CII》1993,37(5):299-306
The mechanism of therapeutic activity for recombinant murine interferon-(rMu IFN) in the treatment of metastatic disease was investigated by comparing effector cell augmentation with therapeutic activity in mice bearing experimental lung metastases (B16-BL6 melanoma). Effector cell functions in spleen, peripheral blood, and lung (the tumor-bearing organ) were tested after 1 week and 3 weeks of rMu IFN administration (i.v. three times per week). Natural killer (NK), lymphokine-activated killer (LAK), cytolytic T lymphocyte (CTL) activities against specific and nonspecific targets, and macrophage tumoristatic activity were measured. rMu IFN demonstrated immunomodulatory activity in most assays of immune function. The optimal therapeutic protocol of rMu IFN (2.5×106 U/kg, three times per week) prolonged survival and decreased the number of pulmonary metastatic foci. This therapeutic activity was correlated with specific CTL activity from pulmonary parenchymal mononuclear cells (PPMC), but not from spleen or blood. Macrophage tumoristatic activity in PPMC also correlated with therapeutic activity, but activity in alveolar macrophages did not. However, therapeutic activity did not correlate with NK or LAK activity at any site. These results demonstrate that the optimal therapeutic protocol is the same as the optimal immunomodulatory dose for pulmonary CTL and macrophage activities. Furthermore, while immunological monitoring may help to optimize treatment protocols, current monitoring procedures that use readily accessible sites, particularly peripheral blood, may not accurately predict the therapeutic efficacy of biological response modifiers in clinical trials.By acceptance of this article, the publisher or recipient acknowledges the right of the US. Government to retain a nonexclusive, royalty-free license in and to any copyright covering the articleThis research was sponsored by the DHHS, under contract N01-23910 with Program Resources Inc. The contents of this publication do not necessarily reflect the views or policies of the Department of Health and Human Services, nor does mention of trade names, commercial products, or organizations imply endorsement by the US Government 相似文献
53.
Ken-ichi Tanaka Shigeru Kohno Takashige Miyazaki Haruko Miyazaki Kotaro Mitsutake Shigefumi Maesaki Mitsuo Kaku Hironobu Koga 《Mycopathologia》1994,127(3):131-134
A latex agglutination test for cryptococcal antigen, the Eiken Latex test (Eiken, Tokyo, Japan), was compared with a monoclonal antibody-based agglutination assay, Pastorex® Cryptococcus (Diagnostics Pasteur, Marneur-la-Coquette, France). In a murine model of disseminated cryptococcosis, the kinetics of the antigen titers by the Eiken Latex were similar to those by the Pastorex® Cryptococcus, but sensitivity was much higher. In HIV-negative patients with pulmonary cryptococcosis, a cryptococcal antigen was detected in 6 of 10 patients by the Eiken Latex test and in only 3 of those patients by the Pastorex® Cryptococcus. The results indicate that the Eiken Latex is more sensitive for the detection of the cryptococcal antigen, even in non-disseminated cryptococcosis. The sensitivity and specificity of the Eiken Latex were examined using 195 sera from 25 patients with pulmonary cryptococcosis and 170 patients with non-cryptococcosis. The cutoff value of 1:8 showed a sensitivity of 76% (19/25) and a specificity of 98.9% (168/170). 相似文献
54.
Cyclooxygenase-2 is a very important physiological enzyme playing key roles in various biological functions especially in the mechanism of pain and inflammation, among other roles, making it a molecule of high interest to the pharmaceutical community as a target. COX 2 enzyme is induced only during inflammatory processes or cancer and reflects no role in the guarding stomach lining. Thus, selective COX-2 inhibition can significantly reduce the adverse effects including GI tract damage and hepatotoxic effects of traditional NSAIDs like aspirin, ibuprofen, etc. Recent developments on COX-2 inhibitors is primarily focused on improving the selectivity index of the drug towards COX-2 along with enhancing the potency of the drug by modifying the scaffolds of Coxibs currently in the market like Celecoxib, Indomethacin, Oxaprozin, etc. We have reported the progress on new COX-2 inhibitors in the last decade (2008–2019) focussing on five heterocyclic rings- Pyrazole, Indole, Oxazole, Pyridine and Pyrrole. The addition of various moieties to these core rings and their structure-activity relationship along with their molecular modelling data have been explored in the article. This review aims to aid medicinal chemists in the design and discovery of better COX-2 inhibitors constructed on these five heterocyclic pharmacophores. 相似文献
55.
Role of virulence factors, cell components and adhesion in Helicobacter pylori-mediated iNOS induction in murine macrophages 总被引:2,自引:0,他引:2
Assmann IA Enders GA Püls J Rieder G Haas R Hatz RA 《FEMS immunology and medical microbiology》2001,30(2):133-138
To investigate the mechanisms involved in Helicobacter pylori-mediated inducible nitric oxide synthase (iNOS) upregulation in mononuclear cells we cocultivated human THP-1 acute monocytic leukemia cells and murine J774A.1 professional macrophages with different H. pylori wild-type strains and mutants. We have shown that H. pylori-mediated iNOS induction in J774A.1 is independent of established virulence factors but dependent on direct interaction between bacteria and cells. In J774A.1, iNOS was equally upregulated by the wild-type strains J99, 26695, P12, and P1 as well as by mutants lacking the cag pathogenicity island, vacA, katA, alpAB genes and the hp0043 gene taking part in lipopolysaccharide biosynthesis when direct cell contact was allowed but not when bacteria and cells were separated by protein-permeable filter membranes. In contrast, iNOS was not induced in THP-1. This indicates that H. pylori-mediated iNOS induction in J774A.1 is independent of important virulence factors whereas cell contact is crucial which suggests a role of adhesion or phagocytosis. 相似文献
56.
Del Moral PM Sala FG Tefft D Shi W Keshet E Bellusci S Warburton D 《Developmental biology》2006,290(1):177-188
Vascular endothelial growth factor-A (VEGF-A) signaling directs both vasculogenesis and angiogenesis. However, the role of VEGF-A ligand signaling in the regulation of epithelial-mesenchymal interactions during early mouse lung morphogenesis remains incompletely characterized. Fetal liver kinase-1 (Flk-1) is a VEGF cognate receptor (VEGF-R2) expressed in the embryonic lung mesenchyme. VEGF-A, expressed in the epithelium, is a high affinity ligand for Flk-1. We have used both gain and loss of function approaches to investigate the role of this VEGF-A signaling pathway during lung morphogenesis. Herein, we demonstrate that exogenous VEGF 164, one of the 3 isoforms generated by alternative splicing of the Vegf-A gene, stimulates mouse embryonic lung branching morphogenesis in culture and increases the index of proliferation in both epithelium and mesenchyme. In addition, it induces differential gene and protein expression among several key lung morphogenetic genes, including up-regulation of BMP-4 and Sp-c expression as well as an increase in Flk-1-positive mesenchymal cells. Conversely, embryonic lung culture with an antisense oligodeoxynucleotide (ODN) to the Flk-1 receptor led to reduced epithelial branching, decreased epithelial and mesenchymal proliferation index as well as downregulating BMP-4 expression. These results demonstrate that the VEGF pathway is involved in driving epithelial to endothelial crosstalk in embryonic mouse lung morphogenesis. 相似文献
57.
目的:建立可快速检测化学物致敏性和刺激性的局部淋巴结试验( LLNA:BrdU-ELISA)改良法,并对化妆品产品进行评价。方法3种化学物(2,4二硝基氯苯( DNCB)、丁子香酚、己基肉桂醛)和3种化妆品产品作为受试物,雌性BALB/c小鼠连续染毒3天,测量小鼠耳缘厚度,第5天腹腔注射BrdU,第6天称耳廓重,分离颌下淋巴结称重并制取单细胞悬液,用ELISA试剂盒检测淋巴细胞增殖。结果 DNCB(1.0%)、己基肉桂醛(25%、50%)和3号粉底霜引起耳肿胀和耳廓重显著增加(P <0.05或P <0.01),可能为刺激物,其他均无刺激性;3种化学物和3号粉底霜致敏检测阳性,其他均为阴性。结论结合小鼠耳肿胀和耳廓重的LLNA:BrdU-ELISA改良法可较好地评价化学物和化妆品产品的致敏性和刺激性,有望在化妆品安全性评价中发挥重要作用。 相似文献
58.
Protein p0071, which originally was introduced as a member of the p120-subfamily of armadillo proteins, common to desmosomes and adhaerens junctions (AJs) and to several other cell structures (centrosomes, midbodies), has been localized by using a series of novel
mono- and polyclonal antibodies generated against various domains of the molecule. By protein analysis and immunolocalization
techniques, protein p0071 has been localized as a plaque protein in AJs of diverse epithelia and certain vascular endothelia,
in the composite junctions (areal compositae) of the intercalated disks of cardiomyocytes, and in the punctate or more extended AJs of the vast majority of cell culture
types examined, including mitotic states. Using these antibodies, we have also shown that this AJ protein occurs only rarely
or is even absent in tissues such as skeletal and smooth muscles, in a series of mesenchymal tissue cells, and in specific
desmosome-rich cells such as those of the upper layers of the epidermis and certain other stratified epithelia and Hassall
corpuscles of the thymus. We have also demonstrated that p0071 is absent from desmosomes. The occurrence of two major subtypes
of lymphatic endothelial cells, one with AJs containing p0071 and one without detectable p0071, is emphasized. Possible structural
and functional roles of p0071 are discussed in light of these new findings regarding its localization, and the addition of
p0071 to the armamentarium of cytodiagnostic cell-type markers is recommended.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
This study was supported by project grants from the German Ministry for Education and Research (BMBF) in a cooperative research
program entitled “Standardization of mesenchymal stem cells for regenerative medicine (START-MSC)” and from the Deutsche Krebshilfe
(project 10–2049) to W.W. Franke. 相似文献
59.
Interleukin-1 Hyperproduction by In Vitro Activated Peripheral Macrophages from Cerebellar Mutant Mice 总被引:2,自引:1,他引:2
B. Kopmels E. E. Wollman J. M. Guastavino N. Delhaye-Bouchaud† D. Fradelizi J. Mariani† 《Journal of neurochemistry》1990,55(6):1980-1985
Several mutations in mice produce complex patterns of neuronal degeneration of the cerebellum and of its afferent pathways. In the staggerer (sg/sg) mutant, atrophy of the lymphoid organs and immunological abnormalities have been described. To search for a possible link between the neurological and the immune disorders in this mutant, we studied the production by its peripheral macrophages of interleukin-1 (IL-1), which roles in both immune and nervous systems are well established. Suspensions of peritoneal and/or spleen macrophages from mutants and their appropriate controls were stimulated in vitro by lipopolysaccharide. Northern and dot blots, performed with murine IL-1 cDNA probes, revealed a clear-cut hyperexpression of IL-1 mRNA in staggerer macrophages. An IL-1 bioassay using the IL-1-responsive D10.G4 cell line also revealed a sixfold increase of IL-1 activity in the macrophage supernatants of staggerer mutant mice. The hyperproduction was found in 3-week to 1-year-old staggerer and also in heterozygous (+/sg) mice. A similar phenomenon existed in cerebellar mutants lurcher, Purkinje cell degeneration (pcd), and to a lesser extent reeler and wobbler, but was absent in the neurological mutants weaver, jimpy, and motor end plate disease (medH). These observations establish that in several point mutations in mice, central nervous degeneration is associated with dysregulation of IL-1 production by peripheral macrophages. 相似文献
60.
建立一种能对MHV_1、MHV_3、JHM、A_(59) 4种常见小鼠肝炎病毒(Murine Hepatitis Virus,MHV)进行分型检测的SNaPshot新方法。根据MHV 4种常见毒株基因序列比对结果,设计内外两对PCR通用引物和4个单碱基延伸引物,提取MHV 4种常见毒株RNA,逆转录后进行PCR扩增,纯化扩增产物,用SNaPshot方法进行单碱基延伸,将产物进行毛细管凝胶电泳,根据电泳结果分析毒株基因型。优化SNaPshot分析条件,进行灵敏度、特异性分析。用ELISA法和SNaPshot方法检测41例小鼠(Mus musculus)血清样本,将阳性样本进行克隆测序检测。当T1~T4引物修饰的poly T的数量分别为0、3、10和15,其浓度比为4︰6︰5︰10,引物大小分别为16 bp、19 bp、26 bp和31 bp时,SNa Phot分型检测MHV c DNA的最低浓度为1.25 mg/L,特异性为100%,与ELISA和T-克隆测序比较,其准确性为100%(41/41),阳性样本均为JHM毒株。实验结果说明,所建立的SNaPshot检测方法能对MHV_1、MHV_3、JHM、A_(59)进行分型检测,并且具有灵敏、特异、准确的优点。 相似文献