BACKGROUND Penicillin-resistant strains of Streptococcus pneumoniae are now found worldwide, and strains with resistance to cephalosporin are being reported. The appropriate antibiotic therapy for pneumococcal pneumonia due to resistant strains remains controversial. METHODS To examine the effect of resistance to penicillin and cephalosporin on mortality, we conducted a 10-year, prospective s...

Penicillin-resistant and penicillin-tolerant mutants have been isolated from group A streptococci mutagenized by ethyl methane sulfonate. The resistant mutants had an elevated minimal growth inhibitory concentration for benzylpenicillin (minimal inhibitory concentration, 0.2 microgram/ml, as compared with the minimal inhibitory concentration of 0.006 microgram/ml in the penicillin-susceptible p...

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 -...

Demerec (1945) and Luria (1946), in studying the resistance of staphylococci to penicillin, found that for a given inoculum (approximately 300,000,000 bacteria) there was a variation in resistance of approximately tenfold for all of their strains; e.g., if the inoculum required 0.1 unit of penicillin for complete inhibition, many of the bacteria in the inoculum would be inhibited by as little a...

There are a number of reports that bacteria which have been made resistant to antibiotics may be rendered normally susceptible by contact with sensitive organisms, with extracts of such organisms, or with culture filtrates. Some of these reports are mutually contradictory in important respects, and the results have not been reproducible regularly by other workers. Voureka (1948) found that when...

The increasing emergence of penicillin-resistant and multiresistant strains of Streptococcus pneumoniae may pose a problem in coming years. We therefore compared sparfloxacin, a new fluoroquinolone with improved potency against streptococci, with amoxicillin, the "gold standard" in this setting, and another fluoroquinolone, ciprofloxacin, in a mouse pneumonia model. Their efficacies against pen...

Since January 1996, and over a 3-year time span, a significant spread of serotype 6B multidrug-resistant (MDR) pneumococci, susceptible to penicillin and resistant to erythromycin, clindamycin, tetracycline, chloramphenicol, and trimethoprim-sulfamethoxazole, was noted in young carriers living in central and southern Greece. Using restriction fragment end labeling and penicillin binding protein...

BACKGROUND Pneumococcal diseases remain a major cause of morbidity and mortality worldwide. Updated data on drug-resistance from different populations may be important to recognize changes in disease patterns. This study assessed current levels of penicillin resistance among Streptococcus Pneumoniae causing pneumonia in Spanish middle age and older adults. METHODS Antimicrobial susceptibility...

Against penicillin-susceptible pneumococci, the activity of sanfetrinem was similar to those of penicillin, amoxicillin, cefotaxime, imipenem, and meropenem, while against penicillin-resistant strains, sanfetrinem and the carbapenems exhibited superior activity (MICs at which 90% of strains are inhibited, < or =1 microg/ml). PBP 1a in the penicillin-susceptible strain and PBP 1a and PBP 2b in t...

This study aimed to identify Staphylococcus sp. and antibiotic resistance in Tutur District, Pasuruan. A total of 273 samples cow's milk were evaluated identified as Furthermore, the test was carried out according CLSI standards. showed 41 isolates 97 positive CMT. The results reported seven resistant antibiotics consisted one multidrug-resistant isolate, i.e. S. saprophyticus which penicillin,...