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71.
Vizoso FJ Corte MD Alvarez A García I del Casar JM Bongera M González LO García-Muñiz JL Allende MT 《The International journal of biological markers》2004,19(4):268-274
BACKGROUND: The protein encoded by the c-erbB-2 gene is a membrane receptor expressed in a variety of solid human cancers and directly related to poor prognosis. The objective of this work was to evaluate the clinical value of the quantification of membranous oncoprotein levels in gastric cancer. MATERIALS AND METHODS: Membranous c-erbB-2 levels were examined by means of a sandwich immunoenzymatic assay in 82 patients with gastric cancer. The median follow-up period for these patients was 16 months. In addition, c-erbB-2 expression was analyzed by immunohistochemistry in 57 gastric carcinomas. RESULTS: Membranous c-erbB-2 levels ranged widely in the studied tumors (44-112,000 NHU/mg protein). Median c-erbB2 content was significantly higher in intestinal-type tumors than in diffuse-type tumors (p = 0.01). In addition, high levels of c-erbB-2 were significantly associated with shorter relapse-free survival and overall survival in patients with resectable gastric carcinomas (p = 0.01 and p = 0.04, respectively). However, the correlation between immunohistochemistry and ELISA determinations did not reach statistical significance. CONCLUSION: Our results suggest a potential prognostic value of membranous c-erbB-2 quantification by immunoenzymatic assay in gastric cancer. However, its possible role in the selection of patients with a view to the possible introduction of Herceptin as a novel drug against gastric cancer is at present uncertain. 相似文献
72.
Alvarez JR Siebert MF Carreño CI Estremera ES Iglesias RB Pereira SS Garcia-Bengochea JB 《Cardiovascular diseases》1981,8(2):259-262
Four widely used bubble oxygenators-the Optiflo I, the Bentley Q 200 A, the Harvey 200, and the Shiley 100 A-were tested and compared in 182 patients undergoing cardiac valve surgery. Fifty-six cases were performed with normothermia and 126 cases incorporated mild hypothermia (28-30 degrees C). There was no significant difference in the average age of the patients (51 yrs) or the perfusion time (60 min). All components of the extracorporeal circuit were identical, and anesthetic regimens and surgical techniques were also similar. In this study, the Shiley 100 A oxygenator was found to be the most suitable for cases requiring mild hypothermia and was generally considered to be the oxygenator of choice. 相似文献
73.
Detection of a Salmonella enterica Serovar California Strain Spreading in Spanish Feed Mills and Genetic Characterization with DNA Microarrays 下载免费PDF全文
Juan Alvarez Steffen Porwollik Idoia Laconcha Vassilis Gisakis Ana Beln Vivanco Iratxe Gonzalez Susana Echenagusia Nieves Zabala Felisa Blackmer Michael McClelland Aitor Rementeria Javier Garaizar 《Applied microbiology》2003,69(12):7531-7534
We performed an epidemiological study on Salmonella isolated from raw plant-based feed in Spanish mills. Overall, 32 different Salmonella serovars were detected. Despite its rare occurrence in humans and animals, Salmonella enterica serovar California was found to be the predominant serovar in Spanish feed mills. Different typing techniques showed that isolates of this serovar were genetically closely related, and comparative genomic hybridization using microarray technology revealed 23 S. enterica serovar Typhimurium LT2 gene clusters that are absent from serovar California. 相似文献
74.
ADP-ribosylation factor/COPI-dependent events at the endoplasmic reticulum-Golgi interface are regulated by the guanine nucleotide exchange factor GBF1 下载免费PDF全文
ADP-ribosylation factor (ARF) mediated recruitment of COPI to membranes plays a central role in transport between the endoplasmic reticulum (ER) and the Golgi. The activation of ARFs is mediated by guanine nucleotide exchange factors (GEFs). Although several ARF-GEFs have been identified, the transport steps in which they function are still poorly understood. Here we report that GBF1, a member of the Sec7-domain family of GEFs, is responsible for the regulation of COPI-mediated events at the ER-Golgi interface. We show that GBF1 is essential for the formation, differentiation, and translocation of pre-Golgi intermediates and for the maintenance of Golgi integrity. We also show that the formation of transport-competent ER-to-Golgi intermediates proceeds in two stages: first, a COPI-independent event leads to the formation of an unstable compartment, which is rapidly reabsorbed in the absence of GBF1 activity. Second, the association of GBF1 with this compartment allows COPI recruitment and leads to its maturation into transport intermediates. The recruitment of GBF1 to this compartment is specifically inhibited by brefeldin A. Our findings imply that the continuous recruitment of GBF1 to spatially differentiated membrane domains is required for sustained membrane remodeling that underlies membrane traffic and Golgi biogenesis. 相似文献
75.
76.
Enrichment and characterization of an anammox bacterium from a rotating biological contactor treating ammonium-rich leachate 总被引:62,自引:0,他引:62
Egli K Fanger U Alvarez PJ Siegrist H van der Meer JR Zehnder AJ 《Archives of microbiology》2001,175(3):198-207
Anaerobic ammonium oxidation with nitrite to N2 (anammox) is a recently discovered microbial reaction with interesting potential for nitrogen removal from wastewater. We enriched an anammox culture from a rotating disk contactor (near K?lliken, Switzerland) that was used to treat ammonium-rich leachate with low organic carbon content. This enrichment led to a relative population size of 88% anammox bacteria. The microorganism carrying out the anammox reaction was identified by analysis of the 16S rDNA sequence and by fluorescence in situ hybridization (FISH) with 16S-rRNA-targeting probes. The percentage sequence identity between the 16S rDNA sequences of the K?lliken anammox organism and the archetype anammox strain Candidatus Brocadia anammoxidans was 90.9%, but between 98.5 and 98.9% with Candidatus Kuenenia stuttgartiensis, an organism identified in biofilms by molecular methods. The K?lliken culture catalyzed the anaerobic oxidation of ammonium with nitrite in a manner seemingly identical to that of Candidatus B. anammoxidans, but exhibited higher tolerance to phosphate (up to 20 mM) and to nitrite (up to 13 mM) and was active at lower cell densities. Anammox activity was observed only between pH 6.5 and 9, with an optimum at pH 8 and a temperature optimum at 37 degrees C. Hydroxylamine and hydrazine, which are intermediates of the anammox reaction of Candidatus B. anammoxidans, were utilized by the K?lliken organisms, and approximately 15% of the nitrite utilized during autotrophic growth was converted to nitrate. Electron microscopy showed a protein-rich region in the center of the cells surrounded by a doughnut-shaped region containing ribosomes and DNA. This doughnut-shape region was observed with FISH as having a higher fluorescence intensity. Similar to Candidatus B. anammoxidans, the K?lliken anammox organism typically formed homogenous clusters containing up to several hundred cells within an extracellular matrix. 相似文献
77.
Biosynthesis of fatty acids and triacylglycerols by 2,6,10,14-tetramethyl pentadecane-grown cells of Nocardia globerula 432 总被引:1,自引:0,他引:1
Héctor M. Alvarez Maria F. Souto Alberto Viale Oscar H. Pucci 《FEMS microbiology letters》2001,200(2):195-200
Nocardia globerula strain 432 was able to synthesize triacylglycerols (TAG) during cultivation on 2,6,10,14-tetramethyl pentadecane (pristane) under nitrogen-limiting conditions. Within these cells, 4,8,12-trimethyl tridecanoic acid was the major fatty acid detected. Fatty acids with an odd number of carbon atoms and minor amounts of even-numbered fatty acids were also observed. Experiments carried out with acrylic acid, an inhibitor of beta-oxidation, suggested that odd-numbered fatty acids such as C15:0, C17:0 and 10-methyl C17:0 were synthesized de novo using propionyl-CoA, the beta-oxidation product, as precursor. Although N. globerula 432 incorporated mainly straight chain fatty acids into TAG, the branched fatty acid 4,8,12-trimethyl tridecanoic acid also appeared, to some extent, in the acylglycerols. The importance of TAG biosynthesis by pristane-grown cells of N. globerula strain 432 is discussed. 相似文献
78.
Rodolfo Valdés Andrés Tamayo Marcos González Sigifredo Padilla Déborah Geada William Ferro Lorely Milá Leonardo Gómez Rosario Alemán Alberto Leyva Cristina García Otto Mendoza Tatiana Alvarez Lamay Dorta Yanet Villega Dobián Cecilia Hasel Aragón Tatiana González Maylín La O Jorge López 《Biotechnology and Bioprocess Engineering》2012,17(1):145-159
Monoclonal antibody (mAb) production methods (ascites, in vitro technologies, transgenic animals, and dicot or monocot transgenic plants; moss, algae) have been improved since they were first developed in 1975. In this study, we illustrate a summary of a study case in which mice, a hollow fiber system, and tobacco transgenic plants were assessed for the production of mAb for vaccine manufacturing and vaccine production. 相似文献
79.
80.