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991.
Bangari DS Sharma A Mittal SK 《Biochemical and biophysical research communications》2005,331(4):1478-1484
Usefulness of adenoviral vectors derived from human adenovirus (HAd) type 5 (HAd5) is mainly limited by wide prevalence of preexisting anti-HAd5 immunity as well as non-specific tissue tropism of these vectors. As an alternative, non-human adenoviral vectors including bovine adenovirus type 3 (BAd3) are currently being investigated. Non-prevalence of BAd3 in humans and its ability to evade preexisting HAd immunity are some of the features that make BAd3 a promising vector for human gene delivery. BAd3 appears to have a tissue tropism distinct from that of HAd5 and also the repertoire of cells efficiently transduced by BAd3 is different. We performed antibody-mediated receptor blocking experiments to show that BAd3 internalization was independent of coxsackievirus-adenovirus receptor, the primary determinant of HAd5 tropism, or integrin alpha(v)beta3, a secondary molecule involved in HAd5 entry. Using homologous and heterologous knob-mediated competition assays with recombinant knobs of HAd5, porcine adenovirus type 3 (PAd3), or BAd3, we observed that BAd3 internalization was independent of the primary receptors of HAd5 and PAd3. These results provide support for further exploration of BAd3 vectors for designing targeted vectors for human gene therapy. 相似文献
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BACKGROUND: Initially described as a pleural tumor, solitaryfibrous tumor of the parotid gland (SFT) is rare and has been reported at a wide range ofanatomic sites. Although cases of SFT arising in the parotid gland have been previously described, a review of the literature failed to reveal cytology-based reports of this entity. CASE: A 42-year-old man presented with a right parotid mass that had gradually enlarged over 3 years. He was otherwise asymptomatic. Fine needle aspiration biopsy of the mass showed a hypercellular smear composed of spindle cells in both clusters and isolated forms, with ovoid nuclei, evenly distributed chromatin, inconspicuous nucleoli and scant to moderate cytoplasm with focally wispy, collagenous, intercellular material. The background was hemorrhagic, without chondromyxoid matrix or inflammatory cells. There was no evidence of a myoepithelial component. A diagnosis of spindle cell neoplasm was rendered. Histologic examination of the total parotidectomy specimen revealed a SFT arising in the parotid gland. The diagnosis was supported by immunohistochemical studies. CONCLUSION: SFT is a well-circumscribed neoplasm composed of short, spindled, plump cells with scanty cytoplasm growing in a haphazard or "patternless" pattern. Tumor cells are intimately admixed with collagenous stroma. Hemangiopericytomalike vessels are frequently seen. Although SFT rarely occurs in the salivary gland and a definitive diagnosis based on cytologic preparations alone is difficult, the diagnosis of SFT can be considered when cytologic examination reveals a hypercellular smear composed of isolated, cohesive clusters of spindled, fibroblastlike cells associated with a collagenous component in ahemorrhagic background. The preoperative magnetic esonance image findings of a highly vascular neoplasm support the diagnosis. 相似文献
996.
Cyclooxygenase 2 inhibition promotes IFN-gamma-dependent enhancement of antitumor responses 总被引:3,自引:0,他引:3
Sharma S Zhu L Yang SC Zhang L Lin J Hillinger S Gardner B Reckamp K Strieter RM Huang M Batra RK Dubinett SM 《Journal of immunology (Baltimore, Md. : 1950)》2005,175(2):813-819
In previous studies, we demonstrated an immune suppressive network in non-small cell lung cancer that is due to overexpression of tumor cyclooxygenase 2 (COX-2). In this study, we assessed the vaccination response to tumor challenge following either pharmacological or genetic inhibition of COX-2 in a murine lung cancer model. Treatment of naive mice with the COX-2 inhibitor, SC-58236, skewed splenocytes toward a type 1 cytokine response, inducing IFN-gamma, IL-12, and IFN-gamma-inducible protein 10, whereas the type 2 cytokines IL-4, IL-5, and IL-10 remained unaltered. Fifty percent of mice receiving SC-58236 and an irradiated tumor cell vaccine completely rejected tumors upon challenge. Those mice that did form tumors following challenge demonstrated a reduced tumor growth. In contrast, all mice either vaccinated with irradiated tumor cells alone or receiving SC-58236 alone showed progressive tumor growth. Studies performed in CD4 and CD8 knockout mice revealed a requirement for the CD4 T lymphocyte subset for the complete rejection of tumors. To determine the role of host COX-2 expression on the vaccination responses, studies were performed in COX-2 gene knockout mice. Compared with control littermates, COX-2(-/-) mice showed a significant tumor growth reduction, whereas heterozygous COX-2(-/+) mice had an intermediate tumor growth reduction following vaccination. In vivo depletion of IFN-gamma abrogated the COX-2 inhibitor-mediated enhancement of the vaccination effect. These findings provide a strong rationale for additional evaluation of the capacity of COX-2 inhibitors to enhance vaccination responses against cancer. 相似文献
997.
Iodine and IFN-gamma synergistically enhance intercellular adhesion molecule 1 expression on NOD.H2h4 mouse thyrocytes 总被引:1,自引:0,他引:1
Sharma RB Alegria JD Talor MV Rose NR Caturegli P Burek CL 《Journal of immunology (Baltimore, Md. : 1950)》2005,174(12):7740-7745
NOD.H2(h4) mice spontaneously develop autoimmune lymphocytic thyroiditis that mimics human Hashimoto's thyroiditis, a disease where iodine, IFN-gamma, and adhesion molecules have all been implicated in the pathogenesis. To study how iodine and IFN-gamma modulate the expression of ICAM-1, we analyzed NOD.H2(h4) thyrocytes in baseline conditions (day 0) and at several time points following supplementation of iodine in the drinking water. On day 0, a small percentage ( approximately 10%) of thyrocytes constitutively expressed ICAM-1. The expression gradually increased to 13, 25, and 41% on days 7, 14 and 28, respectively, returning to baseline (9%) on day 35. The initial ICAM-1 kinetics was paralleled by thyroidal infiltration of CD45(+) hemopoietic cells, which increased from an average of 4% on day 0 to an average of 13, 21, and 24% on days 14, 28, and 35, respectively. To distinguish whether the observed ICAM-1 increase was a direct effect of iodine or a consequence of the immune infiltrate, we treated mouse primary thyrocyte cultures with 0.01 mM sodium iodine and showed a 3-fold increased ICAM-1 expression. To assess interaction between IFN-gamma and iodine, we analyzed CD45 and ICAM-1expression on thyrocytes from NOD.H2(h4) wild-type and NOD.H2(h4) thyr-IFN-gamma transgenic littermates. Strikingly, IFN-gamma interacted synergistically with iodine to enhance ICAM-1 expression on thyrocytes. These findings suggest that iodine and IFN-gamma cooperate to promote thyroidal expression of ICAM-1 in this mouse model of thyroiditis, highlighting the complex interplay present in the pathogenesis of Hashimoto's thyroiditis. 相似文献
998.
Chlamydia trachomatis is an intracellular bacterial pathogen that primarily infects via mucosal surfaces. Using mice with a targeted disruption in IgA gene expression (IgA(-/-) mice), we have studied the contribution of IgA, the principal mucosal antibody isotype, in primary immune defenses against pulmonary C. trachomatis infection. Bacterial burden was comparable between IgA(-/-) and IgA(+/+) animals following C. trachomatis challenge. Serum and pulmonary anti-Chlamydia antibody levels were higher in IgA(-/-) animals, with the exception of IgA. Lung sections of challenged IgA(-/-) mice showed more extensive immunopathology than corresponding IgA(+/+) animals. Real-time PCR analysis demonstrated significantly greater IFN-gamma and TGF-beta mRNA expression in IgA(-/-) as compared to IgA(+/+) animals. Together, these results suggest that IgA may not be necessary for clearance of primary C. trachomatis infection. However, IgA(-/-) mice displayed exaggerated lung histopathology and altered cytokine production, indicating an important role for IgA in regulating C. trachomatis induced pulmonary inflammation and maintenance of mucosal homeostasis. 相似文献
999.
A set of diallel crosses involving 10 parents was made to have information on the extent of heterosis over mid-parent and better parent and inbreeding depression for yield and yield contributing characters under three different environments. Marked heterobeltiosis for grain yield and its important components were observed. For grain yield, 83 crosses showed significant positive heterobeltiosis in all the three sowing dates, however, twenty crosses showed significant consistent heterobeltiosis for grain yield per plant over all the three environments. The maximum heterobeltiosis for grain yield per plant observed was 50.94% (Raj 3765 x HD 2285), 121.08% (PBW 373 x HD 2329) and 93.96% (PBW 373 x HD 2329) under early, normal and late sowing conditions, respectively. Cross PBW 373 x HD 2329 in both early and normal plantings and cross Raj 3765 x HD 2285 under late planting were observed most heterotic for grain yield. The crosses showing heterosis for grain yield were not heterotic for all the characters. Heterosis for grain yield per spike followed by tillers per plant and 1000-grain weight was independently associated with heterosis for grain yield in early and normal plantings. However, heterosis for grain yield per spike, dwarf plant height and tillers per plant contributed maximum towards yield heterosis. Significant inbreeding depression was recorded frequently for yield and yield contributing traits, however, in a few traits it was observed significant negative indicated that F(2) was superior to F(1) considered desirable combination for trait(s). The study reveals good scope for commercial exploitation of heterosis as well as isolation of pure lines among the progenies of heterotic F(1) for improvement of yield levels in bread wheat. 相似文献
1000.
Initially a dose-response curve of phenylephrine was constructed at dose strengths of 1-16 microg/kg in a cumulative manner. Phenylephrine caused a significant rise in the mean arterial pressure, left ventricular systolic pressure, left ventricular contractility, stroke volume and a significant decline in the heart rate. Terazosin was administered in three selected doses of 10, 100 and 300 microg/kg. Following each dose of terazosin, dose-response curve of phenylephrine was constructed. Terazosin, per se, decreased the basal mean arterial pressure, left ventricular systolic pressure, left ventricular contractility and stroke volume significantly in a dose dependent manner with an increase in the heart rate with no significant change in the cardiac output. The baroreflex sensitivity at all the three doses remained unchanged. In conclusion, the present findings support the view that terazosin reduces the blood pressure in a physiologically more favorable manner by maintaining the neural integrity of the cardiovascular system. 相似文献