The in vitro effects of pneumolysin, a sulfhydryl-activated toxin produced by Streptococcus pneumoniae, on various functions of human polymorphonuclear leukocytes (PMNLs) was investigated. Treatment of PMNLs with highly purified toxin significantly inhibited respiratory burst (in response to stimulation), ability to kill opsonized pneumococci, chemotaxis, and random migration. These inhibitions...

The in vitro activity of AZD2563, a novel oxazolidinone, was assessed against 595 Gram-positive cocci, comprising recent surveillance isolates and a collection of resistant (including multiresistant), epidemiologically diverse isolates. The MICs of AZD2563 for staphylococci, pneumococci and enterococci had narrow ranges, 0.25-2 mg/L, with modal MICs of 1 mg/L for staphylococci and pneumococci, ...

Two oxazolidinones and ceftriaxone, imipenem, rifampin, and vancomycin were tested against 162 penicillin-intermediate and 68 penicillin-resistant strains of pneumococci. U-100592 is two- to fourfold more active than U-100766 against penicillin-resistant pneumococci. The MICs of U-100592 at which 90% of the isolates were inhibited were 0.25 and 0.5 microgram/ml for penicillin-intermediate and -...

In the fust of this series of papers suspensions of living pneumococci, which during growth had been protected from the action of air by anaerobic cultivation, were shown to possess the property of uniting with molecular oxygen to form peroxide when exposed to air under conditions unfavorable for cell multiplication (1). The three succeeding papers have dealt with the formation of peroxide (2),...

A survey of the prevalent types of pneumococci responsible for causing pneumonia, pneumococcal meningitis and empyema has been considered a useful line of investigation, because of the aid it may give in elucidating the epidemiology of pneumonias and in determining their specific therapy. Such a survey, however, is an extremely laborious and technical piece of work, involving as it does the inv...

The complement system plays a central role in immune defense against Streptococcus pneumoniae. In order to evade complement attack, pneumococci have evolved a number of mechanisms that limit complement mediated opsonization and subsequent phagocytosis. This review focuses on the strategies employed by pneumococci to circumvent complement mediated immunity, both in vitro and in vivo. At last, si...

1. In the course of experiments for obtaining pneumococci from the oral secretions of human individuals, the "plate method" described in this paper was found to be the most reliable method for isolating pneumococci. 2. An alkaline two-per-cent, glucose-serum-agar was regarded as the most favorable medium for the rapid development of colonies of the pneumococcus. 3. The morphological identificat...

Evidence is here given that polysaccharides can be rendered antigenic by haptogenic adsorption upon a colloid carrier. The polysaccharides studied were those of B. anthracis, the meningococcus, Streptococcus viridans (Bargen), B. proteus, S. morgani, B. dysenteriae, both the Shiga and Hiss types, and the pneumococci. With the polysaccharide of Type III pneumococci, we have been unable in 6 week...

1. In rabbits, guinea pigs, and mice pneumococcus autolysate antitoxin has no effect against generalized infection by the pneumococcus. 2. In a large proportion of cases of pneumonia and sepsis caused by the intratracheal inoculation of large amounts of living pneumococci in normal or sensitized guinea pigs, autolysate antitoxin saves the animal. 3. The autolysate antitoxin is protective in mos...

The following report compares the results of aerobic and anaerobic cultivation for the primary isolation of Streptococcus pneumoniae (the pneumococcus) from the respiratory tract of children. Of 414 specimens of respiratory tract secretions cultured, 65 (15-7%) yielded pneumococci; 31 (47-7%) grew both aerobically and anaerobically, but 34 (52-3%) strains were isolated only from the anaerobic c...