Publications by authors named "K Kanthakumar"

We have studied the effect of salmeterol on both P. aeruginosa interactions with the mucosa of nasal turbinate organ cultures and on pyocyanin-induced (20 microg/ml) and elastase-induced (100 microg/ml) damage to nasal epithelial cells. Organ cultures were exposed to salmeterol either by preincubation with 4 x 10(-7) M salmeterol for 30 min or by pipetting 20 microl of 4 x 10(-7) M salmeterol onto the organ culture surface immediately prior to bacterial inoculation.

View Article and Find Full Text PDF

Toxins that slow ciliary beat are virulence determinants of bacteria that infect or invade ciliated epithelial surfaces. We have previously shown that the effect of the Pseudomonas aeruginosa toxin pyocyanin on ciliary beat is associated with a fall in intracellular cAMP and ATP. We have now investigated whether reduction in intracellular adenosine nucleotides might be a common mechanism of action of other bacterial toxins which slow ciliary beat.

View Article and Find Full Text PDF

Sterile culture filtrates from non-typable Haemophilus influenzae (NTHi) grown in medium containing no antibiotics or 0.25 MIC of amoxycillin, ciprofloxacin or loracarbef were examined for their effect on the ciliary beat frequency (CBF) and structure of human respiratory epithelium. CBF slowing was significantly (P < 0.

View Article and Find Full Text PDF

Exposure of human nasal ciliated epithelium to reactive oxidants generated by the enzymatic xanthine-xanthine oxidase superoxide/hydrogen peroxide (H2O2) and glucose-glucose oxidase H2O2-generating systems, or to reagent H2O2 or hypochlorous acid (HOCl) resulted in significant alterations in ciliary beating. The earliest change noted was the presence of ciliary slowing, progressing eventually to complete ciliary stasis in some areas. Ciliary dyskinesia was seen within the first hour, often from as early as 15 min after exposure of the cells to reactive oxidants.

View Article and Find Full Text PDF

1. Patients with airway infection by Pseudomonas aeruginosa have impaired mucociliary clearance. Pyocyanin is a phenazine pigment produced by P.

View Article and Find Full Text PDF