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101.
Jill M. Westcott Amanda M. Prechtl Erin A. Maine Tuyen T. Dang Matthew A. Esparza Han Sun Yunyun Zhou Yang Xie Gray W. Pearson 《The Journal of clinical investigation》2015,125(5):1927-1943
Tumor cells can engage in a process called collective invasion, in which cohesive groups of cells invade through interstitial tissue. Here, we identified an epigenetically distinct subpopulation of breast tumor cells that have an enhanced capacity to collectively invade. Analysis of spheroid invasion in an organotypic culture system revealed that these “trailblazer” cells are capable of initiating collective invasion and promote non-trailblazer cell invasion, indicating a commensal relationship among subpopulations within heterogenous tumors. Canonical mesenchymal markers were not sufficient to distinguish trailblazer cells from non-trailblazer cells, suggesting that defining the molecular underpinnings of the trailblazer phenotype could reveal collective invasion-specific mechanisms. Functional analysis determined that DOCK10, ITGA11, DAB2, PDFGRA, VASN, PPAP2B, and LPAR1 are highly expressed in trailblazer cells and required to initiate collective invasion, with DOCK10 essential for metastasis. In patients with triple-negative breast cancer, expression of these 7 genes correlated with poor outcome. Together, our results indicate that spontaneous conversion of the epigenetic state in a subpopulation of cells can promote a transition from in situ to invasive growth through induction of a cooperative form of collective invasion and suggest that therapeutic inhibition of trailblazer cell invasion may help prevent metastasis. 相似文献
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Complementation of adeno-associated satellite viral antigens and infectious DNA by temperature-sensitive mutants of herpes simplex virus 总被引:1,自引:0,他引:1
Production of type 4 adeno-associated satellite virus (ASV) structural antigens and infectious DNA was studied using temperature-sensitive (ts) mutants of herpes simplex virus (HSV) types 1 and 2. Seven of the eight mutants studied were unable to synthesize HSV DNA at the nonpermissive temperature. Mutants belonging to three HSV-1 and two HSV-2 complementation groups complemented ASV antigen production while members of two other HSV-1 groups did not. Infectious satellite virus DNA was isolated from the HSV-1 ts-1 complementing system. 相似文献
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Francisco J. Perea M. Amparo Esparza Alma Rosa Villalobos-Arambula Bertha Ibarra John M. Old 《American journal of hematology》1996,51(3):240-242
The origins of the −28 A→C and frameshift Cd 11 −T (Fs Cd 11 −T) alleles were investigated by β-globin cluster haplotype analysis. These alleles were found in a Mexican mestizo family with β-thalassemia (β-thal). The -28 A→C mutation was described previously in Kurdish Jews linked to the most common haplotype in the world (+−−−−++), the same haplotype observed in this Mexican family. Therefore, it is not possible to assess a new origin of the −28 A→C mutation in our population. The Fs Cd 11 −T allele, not reported to date in any other populations, was linked to the −++−−+− haplotype (sixth in frequency in the world). This haplotype has not been reported in association with any β-thal mutant, suggesting a Mexican origin for the Cd 11 −T mutation. © 1995 Wiley-Liss, Inc. 相似文献
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109.
Castilla J Barricarte A Aldaz J García Cenoz M Ferrer T Pelaz C Pineda S Baladrón B Martín I Goñi B Aratajo P Chamorro J Lameiro F Torroba L Dorronsoro I Martínez-Artola V Esparza MJ Gastaminza MA Fraile P Aldaz P 《Epidemiology and infection》2008,136(6):823-832
An outbreak of Legionnaire's disease was detected in Pamplona, Spain, on 1 June 2006. Patients with pneumonia were tested to detect Legionella pneumophila antigen in urine (Binax Now; Binax Inc., Scarborough, ME, USA), and all 146 confirmed cases were interviewed. The outbreak was related to district 2 (22 012 inhabitants), where 45% of the cases lived and 50% had visited; 5% lived in neighbouring districts. The highest incidence was found in the resident population of district 2 (3/1000 inhabitants), section 2 (14/1000). All 31 cooling towers of district 2 were analysed. L. pneumophila antigen (Binax Now) was detected in four towers, which were closed on 2 June. Only the strain isolated in a tower situated in section 2 of district 2 matched all five clinical isolates, as assessed by mAb and two genotyping methods, AFLP and PFGE. Eight days after closing the towers, new cases ceased appearing. Early detection and rapid coordinated medical and environmental actions permitted immediate control of the outbreak and probably contributed to the null case fatality. 相似文献
110.
J. Ventura‐Juarez MR. Campos‐Esparza J. Pacheco‐Yepez J. A López‐Blanco A. Adabache‐Ortíz M. Silva‐Briano R. Campos‐Rodríguez 《Parasite immunology》2016,38(8):503-509
Entamoeba histolytica invades the intestine and other organs during the pathogenesis of amoebiasis. In the early stages, the host organism responds with an inflammatory infiltrate composed mostly of neutrophils. It has been reported that these immune cells, activated by E. histolytica, exert a protective role by releasing proteolytic enzymes and generating reactive oxygen/nitrogen species (ROS/RNS) and antimicrobial peptides. It is now known that neutrophils also produce neutrophil extracellular traps (NETs), which are able to damage and kill pathogens. Studies have shown that intracellular protozoan pathogens, including Toxoplasma gondi, Plasmodium falciparum and Leishmania spp, induce neutrophils to release NETs and are damaged by them. However, the action of this mechanism has not been explored in relation to E. histolytica trophozoites. Through scanning electron, epifluorescence microscopy and viability assays, we show for first time that during in vitro interaction with E. histolytica trophozoites, human neutrophils released NETs that covered amoebas and reduced amoebic viability. These NETs presented histones, myeloperoxidase and decondensed chromatin. The results suggest that NETs participate in the elimination of the parasite. 相似文献