introduction: bacteria and their byproducts are major etiologic factors in endodontic diseases. prevention or reduction of root canal bacterial contamination is the main aim of endodontic treatment. the purpose of this in vitro study was to evaluate the effect of size and taper of master apical file (maf) in reducing bacteria from the apical third of the curved canals using a quantitative scann...

Species colonizing new environments face an uphill battle to become established. Because colonizing populations are often small, opportunities for sexual reproduction may be limited by availability of mates or viable pollen—an example of an Allee effect (1, 2). The presence of amore abundant related species with similar climatic, habitat, and nutritional needs can further reduce the odds of col...

Planktonic larvae of many invertebrates settle preferentially on surfaces covered by bacterial biofilms. The polychaete tubeworm Hydroides elegans is induced to settle by biofilms and is the primary colonizer of newly submerged surfaces in the succession of macrofouling invertebrates in Pearl Harbor, Hawai'i. This study examines cultureindependent community composition, as well as densities of ...

root rot disease of broad-bean caused by fusarium solani is a serious disease of this crop. due to high cost and difficulty of the disease control, interaction between root nodulating bacteria and fusarium. solani were evaluated to use for disease management. broad-bean root nodulating bacteria were isolated and their interaction with f. solani was investigated in culture medium in a completely...

Native bacteria, Pseudomonas and filamentous bacteria were quantified and localized on wheat roots grown in the field using fluorescence in situ hybridization (FISH). Seminal roots were sampled through the season from unploughed soil in a conservation farming system. Such soils are spatially heterogeneous, and many roots grow slowly through hard soil with cracks and pores containing dead roots ...

BACKGROUND Diverse assemblages of microbes colonize plant roots and collectively function as a microbiome. Earlier work has characterized the root microbiomes of numerous plant species, but little information is available for legumes despite their key role in numerous ecosystems including agricultural systems. Legumes form a root nodule symbiosis with nitrogen-fixing Rhizobia bacteria and there...

Colonization-defective, transposon-induced mutants of the efficient root colonizer Pseudomonas fluorescens WCS365 were identified with a gnotobiotic system. Most mutants were impaired in known colonization traits, i.e., prototrophy for amino acids, motility, and synthesis of the O-antigen of LPS (lipopolysaccharide). Mutants lacking the O-antigen of LPS were impaired in both colonization and co...

T cells may interact with a number of bacterial surface antigens, an encounter which has the potential to downmodulate host immune responses. Neisseria meningitidis, a human colonizer and an agent of septicemia and meningitis, expresses Opa proteins which interact with the CEACAM1 receptor expressed on activated T cells. Since CEACAM1 can act as an inhibitory receptor and T cells in subepitheli...