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991.
992.
William J Fisk Ekaterina A Eliseeva Mark J Mendell 《Environmental health : a global access science source》2010,9(1):72
Background
Dampness and mold have been shown in qualitative reviews to be associated with a variety of adverse respiratory health effects, including respiratory tract infections. Several published meta-analyses have provided quantitative summaries for some of these associations, but not for respiratory infections. Demonstrating a causal relationship between dampness-related agents, which are preventable exposures, and respiratory tract infections would suggest important new public health strategies. We report the results of quantitative meta-analyses of published studies that examined the association of dampness or mold in homes with respiratory infections and bronchitis. 相似文献993.
Marta Scandurra Davide Rossi Clara Deambrogi Paola MV Rancoita Ekaterina Chigrinova Michael Mian Michaela Cerri Silvia Rasi Elisa Sozzi Francesco Forconi Maurilio Ponzoni Santiago M Moreno Miguel A Piris Giorgio Inghirami Emanuele Zucca Valter Gattei Andrea Rinaldi Ivo Kwee Gianluca Gaidano Francesco Bertoni 《Hematological oncology》2010,28(2):62-67
Richter's syndrome (RS) represents the transformation of chronic lymphocytic leukaemia (CLL) to aggressive lymphoma and is mostly represented by diffuse large B‐cell lymphoma (DLBCL), with a post‐germinal centre (GC) phenotype, clonally related to the pre‐existing CLL. RS has a very poor prognosis and its pathogenetic mechanisms are poorly understood. In order to gain additional hints in RS pathogenesis, we performed a genome‐wide DNA profiling study of 13 RS phases and eight matched CLL phases using the Affymetrix Human Mapping 250K NspI SNP arrays. Individual genomic profiles were heterogeneous, with no individual lesions occurring in more than half of the cases. However, several observations suggest that MYC pathway might be involved in RS. The 13q13.3‐qter region containing MIRHG1 (MIR‐17‐92), a cluster of microRNA interacting with c‐MYC, was acquired at the time of transformation. The 13q gain was coupled with the gain of c‐MYC and loss of TP53. Translocation of c‐MYC was acquired at transformation in a fraction of cases and this event appeared mutually exclusive with gain of MIRHG1. MYCN, a c‐MYC homologue, was also recurrently gained. By comparing RS with 48 de novo DLBCL, RS presented a significantly lower prevalence of deletions affecting the PRDM1 and TNFAIP3, genes on 6q, known to be associated with a post‐GC phenotype. In conclusion, the genomic profile of RS seems to differ from what observed in de novo DLBCL and in other transformed DLBCL. Genomic lesions occurring in RS are heterogeneous suggesting the existence of different RS subsets, possibly due to different transforming mechanisms. A deregulation of MYC pathway might represent one of the main transformation events in the pathogenesis of a subset of RS clonally related to the previous CLL. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
994.
Rébécca Phaeton Matthew Harris Zewei Jiang Xing Guo Wang Mark H Einstein Gary L Goldberg Arturo Casadevall Ekaterina Dadachova 《Cancer biology & therapy》2010,10(10):1041-1047
Purpose
HPV16 is associated with ∼50% of all cervical cancers worldwide. The E6 and E7 genes of oncogenic HPV types, such as HPV16, are necessary for the HPV transforming function and tumorogenesis making them ideal targets for novel treatments. Radioimmunotherapy employs systemically administered radiolabeled monoclonal antibodies (mAbs) that bind to tumor-associated antigens. Previously we demonstrated in mice that radioimmunotherapy targeting viral antigens with mAb to HPV16 E6 suppressed CasKi cervical tumors expressing high levels of E6 (∼600 copies of HPV per cell). However, that study opened the question whether radioimmunotherapy can suppress the growth of cervical tumors with low E6 and E7 expression, such as may be seen in patients.Experimental Design
We evaluated the expression of E6 in patients'' tumors and in the SiHa cell line expressing low levels of E6 and E7 (1–2 copies of HPV per cell) and found them comparable. We initiated SiHa tumors in nude mice, radiolabeled C1P5 mAb to E6 with a beta-emitter 188-Rhenium (188Re) and treated tumor-bearing mice with: (1) 200 µCi 188Re-C1P5 alone; (2) proteasome inhibitor MG132 alone; (3) MG132 followed by 200 µCi 188Re-C1P5; (4) unlabeled C1P5; (5) 200 µCi 188Re-18B7 (isotype-matching control mAb); (6) no treatment. 188Re-C1P5 alone and in combination with MG-132 significantly retarded tumor growth compared to all control groups.Conclusions
Our data demonstrate the possibility to suppress tumor growth by targeting viral antigens even in cervical tumors with low E6 expression and provide additional evidence for the potential usefulness of radioimmunotherapy targeting HPV-related antigens in the clinic.Key words: cervical cancer, viral antigens, E6 oncoprotein, radioimmunotherapy, 188-rhenium 相似文献995.
Leonova ES Makarov MV Rybalkina EY Nayani SL Tongwa P Fonari A Timofeeva TV Odinets IL 《European journal of medicinal chemistry》2010,45(12):5926-5934
In order to give further insight on the influence of the aromatic ring nature and the presence of the phosphorus substituent at the piperidone nitrogen atom of E,E-3,5-bis((hetero)arylidene)piperid-4-ones on their antitumor properties, a series of phosphorus substituted E,E-3,5-bis(pyridinylmethylene)piperid-4-ones bearing either 3-pyridine or 4-pyridine rings was obtained. Novel NH-3,5-bis(pyridinylmethylene)piperid-4-ones 1a,b were converted into the corresponding N-phosphorylated derivatives 3a-c, 4a-c differing in the substitution at the phosphorus atom (amidophosphates and amidophosphonates), via direct phosphorylation while N-(ω-phosphorylalkyl)-substituted compounds 8a-c were obtained via aldol-crotonic condensation of preformed N-phosphorylalkyl substituted piperidones with the corresponding pyridinecarboxaldehyde. The cytotoxicity screen has revealed that phosphorylated compounds based on E,E-3,5-bis(4-pyridinylmethylene)piperid-4-one framework displayed higher inhibitory properties toward Caov3, A549, KB 3-1 and KB 8-5 human carcinoma cell lines comparing with their analogues with 3-pyridine rings. Introduction of the phosphorus moiety substantially increased the antitumor properties in the case of E,E-3,5-bis(3-pyridinylmethylene)piperid-4-ones derivatives but this influence less pronounced for more active analogues bearing 4-pyridinyl rings. Most of the compounds tested are potent against multi-drug resistant cell line KB 8-5 affording some guidelines for the search of perspective drug-candidates among phosphorus substituted E,E-3,5-bis((hetero)arylidene)piperid-4-ones. 相似文献
996.
Human eosinophils regulate human lung- and skin-derived fibroblast properties in vitro: A role for transforming growth factor β (TGF-β) 总被引:1,自引:0,他引:1 下载免费PDF全文
Francesca Levi-Schaffer Ekaterina Garbuzenko Ann Rubin Reuven Reich Dalia Pickholz Philippe Gillery Herve Emonard Arnon Nagler Francois A. Xavier Maquart 《Proceedings of the National Academy of Sciences of the United States of America》1999,96(17):9660-9665
Eosinophils have been associated with fibrosis. To investigate their direct role in fibrosis, human peripheral blood eosinophil sonicate was added to human lung or dermal fibroblasts, and proliferation ([(3)H]thymidine) and collagen synthesis ([(3)H]proline) were evaluated. Proliferation was enhanced significantly in the monolayers in a dose-dependent manner. The activity of the eosinophil fibrogenic factor(s) remained unaltered when heated (56 degrees C, 30 min). Supernatants of cultured eosinophils (20 min or 18 hr) also enhanced lung fibroblast proliferation, indicating that the preformed mitogenic factor(s) can be released both promptly and with a long kinetic. Eosinophils significantly decreased collagen production in lung fibroblasts while increasing it in dermal fibroblasts. However, eosinophils containing matrix metalloproteinase 9 (zymography) in latent form and tissue inhibitors of metalloproteinases 1 and 2 (reverse zymography) did not influence either fibroblast matrix metalloproteinases or tissue inhibitors of metalloproteinases. Eosinophil sonicate added to skin and lung fibroblasts in tridimensional collagen lattices significantly enhanced lattice contraction. Transforming growth factor beta (TGF-beta) is a major fibrogenic cytokine produced by eosinophils. Therefore, to assess its role, eosinophil sonicate was preincubated with anti-TGF-beta neutralizing antibodies. This treatment partially inhibited proliferation of lung and collagen synthesis of dermal fibroblasts and suppressed the stimulation of lattice contraction, indicating the fibrogenic role of eosinophil-associated TGF-beta. In conclusion, we have shown that eosinophils act as direct modulatory cells in fibroblast proliferation, collagen synthesis, and lattice contraction, in part, through TGF-beta. These data corroborate the importance of eosinophils in skin and lung fibrosis. 相似文献
997.
998.
Ivan Gushchin Pavel Chervakov Pavel Kuzmichev Alexander N. Popov Ekaterina Round Valentin Borshchevskiy Andrii Ishchenko Lada Petrovskaya Vladimir Chupin Dmitry A. Dolgikh Alexander S. Arseniev Mikhail Kirpichnikov Valentin Gordeliy 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(31):12631-12636
Light-driven proton pumps are present in many organisms. Here, we present a high-resolution structure of a proteorhodopsin from a permafrost bacterium, Exiguobacterium sibiricum rhodopsin (ESR). Contrary to the proton pumps of known structure, ESR possesses three unique features. First, ESR''s proton donor is a lysine side chain that is situated very close to the bulk solvent. Second, the α-helical structure in the middle of the helix F is replaced by 310- and π-helix–like elements that are stabilized by the Trp-154 and Asn-224 side chains. This feature is characteristic for the proteorhodopsin family of proteins. Third, the proton release region is connected to the bulk solvent by a chain of water molecules already in the ground state. Despite these peculiarities, the positions of water molecule and amino acid side chains in the immediate Schiff base vicinity are very well conserved. These features make ESR a very unusual proton pump. The presented structure sheds light on the large family of proteorhodopsins, for which structural information was not available previously. 相似文献
999.
1000.