We compared the inoculum effects for 109 recent clinical isolates of the Bacteroides fragilis group of cefoxitin, cefotetan, ceftizoxime, ceftriaxone, and three beta-lactamase inhibitors (clavulanic acid, sulbactam, and tazobactam) and their penicillin-derived components. Bactericidal activity was assayed and morphologic changes were monitored for selected strains exhibiting a large inoculum ef...

Klebsiella pneumoniae strains that are commonly recognized by clinicians and microbiologists are termed as classical K. pneumoniae (cKP). A strain with capsule-associated mucopolysaccharide web is known as hypervirulent K. pneumoniae (hvKP) as it enhances the serum resistant and biofilm production. Aim is to determine and correlate various virulence genes, ESBL, serum bactericidal effect and bi...

Although it is generally believed that bactericidal and bacteriostatic drugs should not be combined in vivo, in vitro experiments using the checkerboard dilution technique revealed no antagonism between penicillin/cephalothin and rolitetracycline but rather additive or synergistic activity of either drug combination in 40 to 50% of 20 Escherichia coli, and 14 Staphylococcus aureus strains. Slig...

Antibiotics cure infections by influencing bacterial growth or viability. Antibiotics can be divided to two groups on the basis of their effect on microbial cells through two main mechanisms, which are either bactericidal or bacteriostatic. Bactericidal antibiotics kill the bacteria and bacteriostatic antibiotics suppress the growth of bacteria (keep them in the stationary phase of growth). One...

A number of antimycobacterial agents were evaluated with respect to their bacteriostatic activity (growth inhibition) versus the bactericidal activity against a clinical isolate of Mycobacterium avium (Mycobacterium avium complex [MAC] strain 101) in relation to the time of exposure and the growth phase of the mycobacteria. In terms of growth inhibition the MAC in the active phase of growth was...

Meningococcal disease is endemic in Brazil, with periodic outbreaks and case fatality rates reach as high as 18 to 20% of cases. Conjugate vaccines against meningococci are immunogenic in healthy children. However, we have previously shown a poor bactericidal antibody response to a Men C conjugate vaccine in Brazilian HIV-infected children and adolescents after a single vaccine administration. ...

The catalytic inactivation of Escherichia coli (E. coli) in water by silver loaded alumina as catalyst was investigated. Ag/Al(2)O(3) and AgCl/Al(2)O(3) catalysts exhibited high bactericidal activity at room temperature in water with no need for any light or electrical power input. Dissolved oxygen which can be catalyzed to reactive oxygen species (ROS) was found to be essential for the strong ...

The bactericidal effect of hydroxyl radical (·OH) generated by combination of photolysis of hydrogen peroxide (H2O2) and sonolysis of water was examined under the condition in which the yield of ·OH increased additively when H2O2 aqueous solution was concomitantly irradiated with laser and ultrasound. The suspension of Staphylococcus aureus mixed with the different concentrations of H2O2 was ir...

The correlation between antibiotic concentrations in serum, serum bactericidal activity, and results of therapy was studied in rabbits with streptococcal endocarditis. Five days of procaine penicillin G reduced bacterial titers to <10 per g in 12 of 14 vegetations in rabbits receiving 75,000 U intramuscularly every 6 h and 10 of 20 in rabbits given 37,500 U. Ten days of 18,750 U every 6 h did n...

OBJECTIVES The goal of the present study was to obtain a comprehensive overview of the bacteriostatic and bactericidal effects of six commonly used antibiotics on planktonic as well as on sessile Burkholderia cepacia complex cells. METHODS The bacteriostatic and bactericidal activities of ceftazidime, ciprofloxacin, meropenem, minocycline, tobramycin and trimethoprim/sulfamethoxazole were det...