Failing in bacteria isolation in a significant number of infections might be due to the involvement of microorganisms nonrecoverable in culture media. The presence cannot be ruled out of nondividing cells or even bacterial products still capable of promoting a host immunological response. Antibiotic therapy, for example, might induce a block of bacterial division and the impossibility of recovering cells in culture media.
View Article and Find Full Text PDFDuring the infectious process, pathogens may reach anatomical sites where they are exposed to substances interfering with their growth. These substances can include molecules produced by the host, and his resident microbial population, as well as exogenous antibacterial drugs. Suboptimal concentrations of inhibitory molecules and stress conditions found in vivo (high or low temperatures, lack of oxygen, extreme pH) might induce in bacteria the activation of survival mechanisms blocking their division capability but allowing them to stay alive.
View Article and Find Full Text PDFObjectives: Bacterial translocation seems to precede the occurrence of overt bacterial infection in patients with cirrhosis. The presence of bacterial DNA in blood and ascites correlates with bacterial translocation and is frequent in patients with advanced cirrhosis without overt infection. Our aim was to search for bacterial DNA in patients with cirrhosis both with and without ascites, and to study its correlation with abnormal intestinal motility or permeability and the presence of bacterial overgrowth.
View Article and Find Full Text PDFIn 2005, pandemic Vibrio parahaemolyticus was reported to have been introduced in Europe: O3:K6 strains were isolated from clinical cases in France and Spain, and were found to be associated with consumption of contaminated seafood. On the contrary, pandemic strains were not isolated from seafood or from the environment itself. Analysis of two V.
View Article and Find Full Text PDFThe viable but non-culturable (VBNC) state is a survival strategy adopted by bacteria when exposed to environmental stresses capable of inducing cell growth inhibition and cell death. This state can be summarized as a quiescent form of life waiting for suitable conditions. This strategy has been shown to be activated by medically important bacteria either when present in natural environments or in the human body during the infection process.
View Article and Find Full Text PDFEnterococci may survive in adverse environments including the human body where bacteriocins, antibiotics, iron-limitation and immune response represent stressing conditions for bacteria that cause division block. In those conditions, bacteria present in the human body would hardly be in an exponentially growing phase but would mostly be in physiological states such as starvation or the viable but nonculturable (VBNC) state. The possibility that the starved and VBNC bacteria can maintain their ability to adhere to living and inanimate substrates is the first mandatory step for them potentially to cause an infection process.
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