scholarly journals Role of Cholesterol and the Ganglioside GM1 in Entry and Short-Term Survival of Brucella suis in Murine Macrophages

2002 ◽  
Vol 70 (3) ◽  
pp. 1640-1644 ◽  
Author(s):  
Aroem Naroeni ◽  
Françoise Porte
Keyword(s):  
Lipid Rafts ◽  
Endocytic Pathway ◽  
Host Cells ◽  
Short Term ◽  
Term Survival ◽  
Murine Macrophages ◽  
Brucella Suis ◽  
Phagosomal Membrane ◽  
Short Term Survival

ABSTRACT Brucella species are gram-negative, facultative intracellular bacteria that infect humans and animals. These organisms can survive and replicate within a membrane-bound compartment inside professional and nonprofessional phagocytic cells. Inhibition of phagosome-lysosome fusion has been proposed as a mechanism for intracellular survival in both types of cells. We have previously shown that the maturation inhibition of the Brucella-containing phagosome appears to be restricted at the phagosomal membrane, but the precise molecular mechanisms and factors involved in this inhibition have yet to be identified. Interestingly, recent studies have revealed that caveolae or lipid rafts are implicated in the entry of some microorganisms into host cells and mediate an endocytic pathway avoiding fusion with lysosomes. In this study, we investigated the role of cholesterol and the ganglioside GM1, two components of lipid rafts, in entry and short-term survival of Brucella suis in murine macrophages, by using cholesterol-sequestering (filipin and β-methyl cyclodextrin) and GM1-binding (cholera toxin B) molecules. Our results suggest that lipid rafts may provide a portal for entry of Brucella into murine macrophages under nonopsonic conditions, thus allowing phagosome-lysosome fusion inhibition, and provide further evidence to support the idea that the phagosome maturation inhibition is restricted at the phagosomal membrane.

scholarly journals States Of Wisdom In Marketing During An Era Of Economic Turbulence

2011 ◽  
Vol 2 (9) ◽  
Author(s):  
Jack A. Lesser ◽  
Donald E. Saunders
Keyword(s):  
Great Depression ◽  
Cost Reduction ◽  
Short Term ◽  
Term Survival ◽  
Marketing Innovation ◽  
The Great Depression ◽  
Short Term Survival

In 1975, Cundiff (1975) wrote an editorial in the Journal of Marketing titled, What is the Role of Marketing in a Recession? The 1974/1975 recession was more damaging to the economy than any recession since the Great Depression. Implicit in his editorial was the momentary concern corporations would emphasize cost reduction over marketing innovation to insure their short-term survival. Numerous articles were published in response to his article about how marketing and consumers appeared to be changing during the period.

scholarly journals Management of metastatic urothelial cancer: the role of surgery as an adjunct to chemotherapy

2013 ◽  
Vol 3 (6-S4) ◽  
pp. 228 ◽  
Author(s):  
Robert S. Svatek ◽  
Arlene Siefker-Radtke ◽  
Colin P. Dinney
Keyword(s):  
Metastatic Disease ◽  
Poor Prognosis ◽  
Multidisciplinary Approach ◽  
Urothelial Cancer ◽  
Short Term ◽  
Term Survival ◽  
Metastatic Urothelial Cancer ◽  
Localized Disease ◽  
Short Term Survival

Metastatic or unresectable disease is identified in approximately20% of patients presenting with invasive urothelial cancer. Inaddition, up to 50% of patients will develop metastases followingradical cystectomy for clinically localized disease. Multiagentcisplatin-based chemotherapy is considered standard first-linetreatment for these patients. Although urothelial cancer is considereda chemosensitive tumour, metastatic disease is associatedwith poor prognosis and short-term survival. Here, we review therole of a multidisciplinary approach to treating patients with metastaticurothelial cancer.

Genetic determinants of lung cancer short-term survival: the role of glutathione-related genes

Lung Cancer ◽  
2002 ◽  
Vol 35 (3) ◽  
pp. 221-229 ◽  
Author(s):  
Ping Yang ◽  
Akira Yokomizo ◽  
Henry D Tazelaar ◽  
Randolph S Marks ◽  
Timothy G Lesnick ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Genetic Determinants ◽  
Short Term ◽  
Term Survival ◽  
Short Term Survival

scholarly journals Role of the Brucella suis Lipopolysaccharide O Antigen in Phagosomal Genesis and in Inhibition of Phagosome-Lysosome Fusion in Murine Macrophages

2003 ◽  
Vol 71 (3) ◽  
pp. 1481-1490 ◽  
Author(s):  
Françoise Porte ◽  
Aroem Naroeni ◽  
Safia Ouahrani-Bettache ◽  
Jean-Pierre Liautard
Keyword(s):  
Molecular Mechanisms ◽  
Cell Types ◽  
Host Cells ◽  
Phagocytic Cells ◽  
Murine Macrophages ◽  
O Antigen ◽  
Brucella Suis ◽  
Important Virulence Factor ◽  
Membrane Bound

ABSTRACT Brucella species are gram-negative, facultative intracellular bacteria that infect humans and animals. These organisms can survive and replicate within a membrane-bound compartment inside professional and nonprofessional phagocytic cells. Inhibition of phagosome-lysosome fusion has been proposed as a mechanism for intracellular survival in both cell types. However, the molecular mechanisms and the microbial factors involved are poorly understood. Smooth lipopolysaccharide (LPS) of Brucella has been reported to be an important virulence factor, although its precise role in pathogenesis is not yet clear. In this study, we show that the LPS O side chain is involved in inhibition of the early fusion between Brucella suis-containing phagosomes and lysosomes in murine macrophages. In contrast, the phagosomes containing rough mutants, which fail to express the O antigen, rapidly fuse with lysosomes. In addition, we show that rough mutants do not enter host cells by using lipid rafts, contrary to smooth strains. Thus, we propose that the LPS O chain might be a major factor that governs the early behavior of bacteria inside macrophages.

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