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Laura Stanbery Nisha J D'Silva Julia S Lee Carol R Bradford Thomas E Carey Mark E Prince Gregory T Wolf Francis P Worden Kitrina G Cordell Elizabeth M Petty 《Translational oncology》2010,3(4):239-245
The purpose of this work was to determine SEPT9_v1 expression levels in head and neck squamous cell carcinoma (HNSCC) and to analyze whether SEPT9_v1 expression is relevant to clinical outcomes. Recently, the SEPT9 isoform SEPT9_v1 has been implicated in oncogenesis, and methylation of the SEPT9 promoter region was reported in HNSCC. These findings led us to hypothesize that SEPT9_v1 could be differently expressed in HNSCC. To determine whether SEPT9_v1 is expressed in HNSCC, tissue microarray immunohistochemical analysis was performed using a SEPT9_v1-specific antibody. Tissue microarrays stained with a polyclonal SEPT9_v1-specific antibody was used to determine protein expression levels in HNSCC tissue samples, some with known clinical outcomes. This analysis showed that SEPT9_v1 is in fact highly expressed in HNSCC compared with normal epithelium, and high expression levels directly correlated with poor clinical outcomes. Specifically, a high SEPT9_v1 expression was associated with decreased disease-specific survival (P = .012), time to indication of surgery at primary site (P = .008), response to induction chemotherapy (P = .0002), and response to chemotherapy (P = .02), as well as advanced tumor stage (P = .012) and N stage (P = .0014). The expression of SEPT9_v1 was also strongly correlated with smoking status (P = .00094). SEPT9_v1 is highly expressed in HNSCC, and a high expression of SEPT9_v1 is associated with poor clinical outcomes. These data indicate that SEPT9_v1 warrants additional investigation as a potential biomarker for HNSCC. 相似文献
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Justin Mancini Brooke Weckselblatt Yoonjie K. Chung Julia C. Durante Steven Andelman Jessica Glaubman Justin D. Dorff Samhita Bhargava Rebeccah S. Lijek Katherine P. Unger Iruka N. Okeke 《Journal of bacteriology》2011,193(18):4813-4820
Heat-resistant agglutinin 1 (Hra1) is an accessory colonization factor of enteroaggregative Escherichia coli (EAEC) strain 042. Tia, a close homolog of Hra1, is an invasin and adhesin that has been described in enterotoxigenic E. coli. We devised a PCR-restriction fragment length polymorphism screen for the associated genes and found that they occur among 55 (36.7%) of the enteroaggregative E. coli isolates screened, as well as lower proportions of enterotoxigenic, enteropathogenic, enterohemorrhagic, and commensal E. coli isolates. Overall, 25%, 8%, and 3% of 150 EAEC strains harbored hra1 alone, tia alone, or both genes, respectively. One EAEC isolate, 60A, produced an amplicon with a unique restriction profile, distinct from those of hra1 and tia. We cloned and sequenced the full-length agglutinin gene from strain 60A and have designated it hra2. The hra2 gene was not detected in any of 257 diarrheagenic E. coli isolates in our collection but is present in the genome of Salmonella enterica serovar Heidelberg strain SL476. The cloned hra2 gene from strain 60A, which encodes a predicted amino acid sequence that is 64% identical to that of Hra1 and 68% identical to that of Tia, was sufficient to confer adherence on E. coli K-12. We constructed an hra2 deletion mutant of EAEC strain 60A. The mutant was deficient in adherence but not autoaggregation or invasion, pointing to a functional distinction from the autoagglutinin Hra1 and the Tia invasin. Hra1, Tia, and the novel accessory adhesin Hra2 are members of a family of integral outer membrane proteins that confer different colonization-associated phenotypes. 相似文献
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Julia L. Blanchard 《Oikos》2011,120(4):481-482
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R van Reis A S Lubiniecki R A Olson R R Stromberg J A Madsen L I Friedman 《Journal of immunology (Baltimore, Md. : 1950)》1984,133(2):758-763
The production of human gamma-interferon (HuIFN-gamma) in unfractionated and nylon wool column-fractionated leukocyte cell cultures stimulated with PMA and PHA was investigated. Production was studied with normal and reduced autologous serum protein levels in 96-hr spinner cultures. A 10- to 15-fold enhancement of production and a 50-fold increase in specific activity of crude HuIFN-gamma was demonstrated in nylon column-fractionated/reduced serum cell cultures. Kinetic analysis revealed a production rate maximum within 6 hr of induction in unprocessed cell cultures, whereas production occurred at an essentially constant rate for 48 hr in fractionated cell cultures. 相似文献
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When rats were confronted with the novel experience of a new environment and stressful handling procedure their body temperature increased within minutes. At the same time β-endorphin-like immunoreactivity in the plasma increased dramatically. The stress-induced hyperthermia could be antagonized or reversed by the active, not however, by the inactive enantiomer of naloxone. The data provide evidence for a physiological role of endorphins. 相似文献