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991.
Xue G Liu RY Li Y Cheng Y Liang ZH Wu JX Zeng MS Tian FZ Huang W 《Cancer immunology, immunotherapy : CII》2007,56(11):1831-1843
Backgroud and objective Dendritic cells play an important role in initiation and regulation of immune responses. Previous studies demonstrated that
intratumoral administration of 6Ckine-modified DCs enhanced local and systemic antitumor effects. Herein we report the investigation
of the specific CTL responses elicited by adenoviral 6Ckine/IFNγ fusion gene-modified DCs in vitro.
Methods Human monocyte-derived DCs were modified with an adenoviral vector encoding 6Ckine/IFNγ fusion protein (Ad-6Ckine/IFNγ), and
then investigated the effect of 6Ckine/IFNγ fusion protein on the maturation, cytokine and chemokine secretion of DCs, and
their activities of recruiting and activating T cells in vitro were investigated.
Results 6Ckine/IFNγ fusion protein induced DC maturation characterized with the upregulation of CD83 and CCR7. And it up-regulated
the expression of RANTES and IL-12p70, down-regulated that of IL-10 in DCs. Additionally, 6Ckine/IFNγ markedly increased DC’s
recruiting ability for naive T cells, benefiting from the enhanced expression of chemokines 6Ckine and RANTES in DCs. Fusion
gene-modified DCs significantly promoted the proliferation of autologous T cells, induced Th1 differentiation by upregulating
the expression of IL-2 and T-bet in T cells, and increased specific cytotoxicity of CTLs against specific tumor cells, HepG2
or LoVo cells, respectively.
Conclusion Combining the effects of 6Ckine and IFNγ, Ad-6Ckine/IFNγ modified DCs induced enhanced CTL responses in vitro, which indicated
that Ad-6Ckine/IFNγ modified DCs might be used as an adjuvant to trigger an effective antitumor immune response.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Gang Xue, Ran-yi Liu, Yan Li contributed equally to this work. 相似文献
992.
In vivo functions of mitogen-activated protein kinases: conclusions from knock-in and knock-out mice 总被引:4,自引:0,他引:4
Multicellular organisms achieve intercellular communication by means of signalling molecules whose effect on the target cell
is mediated by signal transduction pathways. Such pathways relay, amplify and integrate signals to elicit appropriate biological
responses. Protein kinases form crucial intermediate components of numerous signalling pathways. One group of protein kinases,
the mitogen-activated protein kinases (MAP kinases) are kinases involved in signalling pathways that respond primarily to
mitogens and stress stimuli. In vitro studies revealed that the MAP kinases are implicated in several cellular processes,
including cell division, differentiation, cell survival/apoptosis, gene expression, motility and metabolism. As such, dysfunction
of specific MAP kinases is associated with diseases such as cancer and immunological disorders. However, the genuine in vivo
functions of many MAP kinases remain elusive. Genetically modified mouse models deficient in a specific MAP kinase or expressing
a constitutive active or a dominant negative variant of a particular MAP kinase offer valuable tools for elucidating the biological
role of these protein kinases. In this review, we focus on the current status of MAP kinase knock-in and knock-out mouse models
and their phenotypes. Moreover, examples of the application of MAP kinase transgenic mice for validating therapeutic properties
of specific MAP kinase inhibitors, and for investigating the role of MAP kinase in pathogen-host interactions will be discussed. 相似文献
993.
994.
Uveitis is a potentially sight-threatening inflammatory eye disease caused by multiple infectious and non-infectious etiologies for which the standard of care involves corticosteroids or various immunomodulary therapy (IMT) drugs. These available treatments, although effective, may cause significant morbidity and sometimes mortality in uveitis patients due to their toxic side-effects and the necessity of long-term therapy to prevent recurrences. In order to avoid the systemic toxicity ofcorticosteroids and IMT or the repeated injections of local steroids necessary to control ocular inflammation, and to prevent development of cumulative damage resulting from recurrent episodes of inflammation, researchers have developed a number of local corticosteroid sustained-release devices that can be implanted directly into the vitreous of the eye, at the site of the inflammatory disease. Preliminary studies of such a device, the fluocinolone acetonide (Retisert) implant, have shown significant reductions in the number of inflammatory episodes and decreased reliance on systemic corticosteroids or other IMT. This review explores the current research evaluating the fluocinolone sustained-release intravitreal implant in the treatment of posterior uveitis and the implications for its future use on a wider scale. 相似文献
995.
Wu IC Wu DC Hsu PI Lu CY Yu FJ Wang TE Chang WH Chen JJ Kuo FC Wu JY Wang WM Bair MJ 《Helicobacter》2007,12(6):633-637
BACKGROUND: Different kinds of proton pump inhibitor-based triple therapies could result in different Helicobacter pylori eradication rates. AIM: The aims of this study were to compare the efficacy and safety of rabeprazole- and esomeprazole-based triple therapy in primary treatment of H. pylori infection in Taiwan. PATIENTS AND METHODS: From June 2005 to March 2007, 420 H. pylori-infected patients were randomly assigned to receive a 7-day eradication therapy with either esomeprazole 40 mg daily (EAC group, n = 209) or rabeprazole 20 mg b.i.d. (RAC group, n = 211) in combination with amoxicillin 1 g b.i.d. and clarithromycin 500 mg b.i.d.. Follow-up endoscopy with biopsy was done 12-16 weeks after completion of eradication therapy. Those who refused endoscopic exams underwent (13)C-urea breath test to assess the treatment response. RESULTS: Intention-to-treat analysis revealed that the eradication rate was 89.4% in the EAC group and 90.5% in RAC groups (p-value = .72). All of the subjects returned for assessment of compliance (100% in EAC group vs. 99.5% in RAC group, p-value = .32) and adverse events (3.83% in EAC group vs. 6.16% in RAC group, p-value = .27). Sixty (28.7%) and 37 (17.6%) patients in EAC and RAC group, respectively, refused endoscopy and underwent a (13)C-urea breath test to determine the treatment effect. CONCLUSION: In conclusion, rabeprazole- and esomeprazole-based primary therapies for H. pylori infection are comparable in efficacy and safety. 相似文献
996.
Oliveira SM Leite Vilamaior PS Corradi LS Góes RM Taboga SR 《Cell biology international》2007,31(3):235-245
Mongolian gerbils (Meriones unguiculatus) were grouped into two experimental groups: GEx.01 suffered orchiectomy and after 30 days received doses of testosterone cipionate (T), while GEx.02 received weekly and alternated doses of the anti-androgens cyproterone acetate and flutamide for 30 days, and the animals were then euthanized. Structural evaluation reveals a more intense reduction in epithelial height in GEx.02. Smooth muscle cells (SMC) presented a star-shaped aspect after 30 days of hormonal ablation and basal membrane was shown to be more intensely grooved in GEx.01. In both groups, after hormonal replacement, recovery in epithelial height could be noted and the SMC presented its phenotypes, but an increase in RER was seen, characterizing a modulation from its contractile to secreting phenotype. In conclusion, the prostate presented involution capacity after androgen ablation and the ability to reorganize after hormonal replacement, but events resulting from orchiectomy and subsequent T replacement were shown to be more aggressive to the prostate. 相似文献
997.
Osteopontin overexpression in breast cancer: knowledge gained and possible implications for clinical management 总被引:5,自引:0,他引:5
Osteopontin (OPN) is a secreted protein that is overexpressed in a number of human cancers, and has been associated with increased metastatic burden and poor prognosis in breast cancer patients. The OPN protein contains several conserved structural elements including heparin- and calcium-binding domains, a thrombin-cleavage site, a CD44 binding site, and two integrin-binding sites. Experimental studies have shown that the ability of OPN to interact with a diverse range of factors, including cell surface receptors (integrins, CD44), secreted proteases (matrix metalloproteinases, urokinase plasminogen activator), and growth factor/receptor pathways (TGFalpha/EGFR, HGF/Met) is central to its role in malignancy. These complex signaling interactions can result in changes in gene expression, which ultimately lead to alterations in cell properties involved in malignancy such as adhesion, migration, invasion, enhanced tumor cell survival, tumor angiogenesis, and metastasis. Therefore, OPN is not merely associated with cancer, but rather it plays a multi-faceted functional role via complex molecular cross-talk with other factors. This review will focus on the role of OPN in breast cancer, in particular on the malignancy-promoting aspects of OPN that may reveal opportunities for new approaches to the clinical management of breast cancer. 相似文献
998.
Christian Lavoie C. Josh Donlan Karl Campbell Felipe Cruz G. Victor Carrion 《Biological invasions》2007,9(2):139-148
Non-native mammals are major drivers of ecosystem change and biodiversity loss; this is especially apparent on islands. However,
techniques exist to remove non-native mammals, providing a powerful conservation tool. Conservation practitioners are now
targeting larger islands for restoration. Leveraging existing and developing new techniques and technologies will prove critical
to successful eradications on large islands. Using the removal of introduced goats (Capra hircus) from Santiago Island, Galápagos as a case study, we present a suite of Geographic Information System (GIS) tools that aid
island conservation actions. GIS tools were incorporated into the three phases of the eradication campaign: planning, hunting,
and monitoring. Further, these tools were adopted for three eradication techniques: ground-based hunting, aerial hunting by
helicopter, and Judas goats. These geographic approaches provide a foundation for statistical, spatial, and economic analyses
that should increase the capability and efficiency of removal campaigns. Given limited conservation funds and the dire status
of many insular species, efficiently removing non-native mammals from islands is of paramount global conservation importance. 相似文献
999.
Takeshi Harayama Hideo Shindou Yoshihiro Kita Eiji Otsubo Kazushige Ikeda Shoichi Chida Timothy E. Weaver Takao Shimizu 《Journal of lipid research》2015,56(7):1370-1379
The surfactant proteins (SPs), SP-B and SP-C, are important components of pulmonary surfactant involved in the reduction of alveolar surface tension. Quantification of SP-B and SP-C in surfactant drugs is informative for their quality control and the evaluation of their biological activity. Western blot analysis enabled the quantification of SP-B, but not SP-C, in surfactant drugs. Here, we report a new procedure involving chemical treatments and LC-MS to analyze SP-C peptides. The procedure enabled qualitative analysis of SP-C from different species with discrimination of the palmitoylation status and the artificial modifications that occur during handling and/or storage. In addition, the method can be used to estimate the total amount of SP-C in pulmonary surfactant drugs. The strategy described here might serve as a prototype to establish analytical methods for peptides that are extremely hydrophobic and behave like lipids. The new method provides an easy measurement of SP-C from various biological samples, which will help the characterization of various experimental animal models and the quality control of surfactant drugs, as well as diagnostics of human samples. 相似文献
1000.
Abeba Demelash Lukas W. Pfannenstiel Charles S. Tannenbaum Xiaoxia Li Matthew F. Kalady Jennifer DeVecchio Brian R. Gastman 《The Journal of biological chemistry》2015,290(36):21962-21975
Unlike other antiapoptotic Bcl-2 family members, Mcl-1 also mediates resistance to cancer therapy by uniquely inhibiting chemotherapy-induced senescence (CIS). In general, Bcl-2 family members regulate apoptosis at the level of the mitochondria through a common prosurvival binding groove. Through mutagenesis, we determined that Mcl-1 can inhibit CIS even in the absence of its apoptotically important mitochondrion-localizing domains. This finding prompted us to generate a series of Mcl-1 deletion mutants from both the N and C termini of the protein, including one that contained a deletion of all of the Bcl-2 homology domains, none of which impacted anti-CIS capabilities. Through subsequent structure-function analyses of Mcl-1, we identified a previously uncharacterized loop domain responsible for the anti-CIS activity of Mcl-1. The importance of the loop domain was confirmed in multiple tumor types, two in vivo models of senescence, and by demonstrating that a peptide mimetic of the loop domain can effectively inhibit the anti-CIS function of Mcl-1. The results from our studies appear to be highly translatable because we discerned an inverse relationship between the expression of Mcl-1 and of various senescence markers in cancerous human tissues. In summary, our findings regarding the unique structural properties of Mcl-1 provide new approaches for targeted cancer therapy. 相似文献