In Vitro Effect on Group A Streptococci of Loracarbef versus Cefadroxil, Cefaclor and Penicillin V

1993 ◽  
Vol 25 (1) ◽  
pp. 37-42
Author(s):  
Carl Kamme ◽  
Ann-Cathrine Petersson
PEDIATRICS ◽  
1963 ◽  
Vol 31 (1) ◽  
pp. 22-28
Author(s):  
Maxwell Stillerman ◽  
Stanley H. Bernstein ◽  
Martha Smith ◽  
Jack D. Gorvoy

The relative effectiveness of erythromycin propionate and K penicillin V in two dosage schedules was evaluated in the treatment of 261 cases of acute pharyngitis from which Group A hemolytic streptococci were recovered from December, 1958, to June, 1959. Erythromycin propionate, in a daily dose of 30 mg/kg up to 1.0 gm, and K penicillin V, in daily doses of 375 mg and 750 mg, were administered orally for 10 days. The adjusted bacterial cure rate was 78% among 86 patients treated with erythromycin, 72% among 102 patients treated with K penicillin V, 375 mg, and 88% among 73 patients treated with K penicillin V, 750 mg. The data indicate that K penicillin V was more effective in eradicating Group A streptococci from the pharynx in a daily dose of 750 mg than 375 mg, and suggest that erythromycin propionate in the dosage used, was less effective than K penicillin V, 750 mg, but equally as effective as K penicillin V, 375 mg daily. The incidence, time of occurrence, and results of retreatments of bacterial relapses are presented, and two possible causes of relapses are considered.


1952 ◽  
Vol 95 (1) ◽  
pp. 25-38 ◽  
Author(s):  
Armine T. Wilson ◽  
Herman Rosenblum

The measurement in vitro of lactenin, the antistreptococcal substance of milk, is affected by the size of the inoculum, the temperature of incubation, and the type of medium employed. Hemolytic streptococci belonging to the several serological groups vary in susceptibility to lactenin. All group A streptococci, regardless of type, are highly sensitive to it, and milk receiving a small inoculum sterilizes itself within 48 hours or less. By contrast, most strains of groups B, C, D, and E, although they may temporarily be inhibited, ultimately achieve full growth. Strains belonging to groups F, G, H, K, and L vary in sensitivity, some being fully inhibited and others achieving full growth. When streaked on the surface of milk-agar plates and examined at the end of 24 hours the streptococci fall into two classes: sensitive strains which do not produce visible colonies on the plate, and resistant strains which grow excellently. Very few strains show an intermediate degree of sensitivity. Human and goat milk contain an antistreptococcal principle which appears to be the same as the lactenin of cow milk, since streptococci which are inhibited by milk from one species are inhibited by milk from the others, and vice versa.


2002 ◽  
Vol 70 (4) ◽  
pp. 2166-2170 ◽  
Author(s):  
James B. Dale ◽  
Edna Y. Chiang ◽  
David L. Hasty ◽  
Harry S. Courtney

ABSTRACT Virtually all group A streptococci (GAS) produce streptolysin S (SLS), a cytolytic toxin that is responsible for the beta-hemolysis surrounding colonies of the organisms grown on blood agar. SLS is an important virulence determinant of GAS, and recent studies have identified a nine-gene locus that is responsible for synthesis and transport of the toxin. SLS is not immunogenic; thus, no neutralizing antibodies are evoked during the course of natural infection. In the present study, we show that a synthetic peptide containing amino acid residues 10 to 30 of the putative SLS (SagA) propeptide [SLS(10-30)] coupled to keyhole limpet hemocyanin evoked antibodies in rabbits that completely neutralized the hemolytic activity of the toxin in vitro. Inhibition of hemolysis was reversed by preincubation of the immune serum with soluble, unconjugated peptide, indicating the specificity of the antibodies. In addition, antibodies that were affinity purified over an SLS(10-30) peptide column completely inhibited SLS-mediated hemolysis. The SLS(10-30) antisera did not opsonize group A streptococci; however, when combined with type-specific M protein antisera, the SLS antibodies significantly enhanced phagocytosis mediated by M protein antibodies. Thus, we have shown for the first time that it is possible to raise neutralizing antibodies against one of the most potent bacterial cytolytic toxins known. Our data also provide convincing evidence that the sagA gene actually encodes the SLS peptide of GAS. The synthetic peptide may prove to be an important component of vaccines designed to prevent GAS infections.


1967 ◽  
Vol 71 (1) ◽  
pp. 132-137 ◽  
Author(s):  
Milton Markowitz ◽  
Irving Kramer ◽  
Eugene Goldstein ◽  
Anthony Perlman ◽  
Donald Klein ◽  
...  

1959 ◽  
Vol 110 (4) ◽  
pp. 617-628 ◽  
Author(s):  
Marie Judith Foley ◽  
W. Barry Wood

A quantitative study of the combined antiphagocytic effects of the M protein and the hyaluronic acid capsules of four strains of Group A streptococci revealed the following facts relating to their intraperitoneal virulence in mice and rats: 1. The most virulent strain, S23M (matt), produced both a large hyaluronic acid capsule and a full complement of M protein, the combined effects of which rendered the organism highly resistant to surface phagocytosis. 2. The slightly less virulent strain, T14/46 (matt virulent) was somewhat more susceptible to surface phagocytosis owing to the fact that its smaller capsule was less antiphagocytic than that of the S23M organism. 3. The glossy variant of the S23 strain (S23G), which ranked third in virulence, was still more susceptible to surface phagocytosis because of its lack of detectable M substance. Its large hyaluronic acid capsule, however, was capable of protecting it against phagocytosis on glass. 4. The least virulent strain, T14 (matt avirulent), was the most susceptible of all to phagocytosis. Though it possessed both M substance and capsule, which together prevented its phagocytosis on glass, each of them was shown to be quantitatively and functionally deficient as compared to Strain S23M. The differences in phagocytability, which appear to be directly related to the pathogenicity of the organisms, could be adequately demonstrated in vitro only by phagocytic tests designed to measure surface phagocytosis in the absence of opsonins. This fact is in keeping with the observation, previously reported, that surface phagocytosis plays a critical role in the defense of the host, particularly during the earliest stages of experimental streptococcal infections. Its possible relation to suppuration during the later stages of infection is also discussed.


Author(s):  
Tsubasa Ikeda ◽  
Rihito Suzuki ◽  
Wanchun Jin ◽  
Jun-ichi Wachino ◽  
Yoshichika Arakawa ◽  
...  

Streptococcus pyogenes (group A Streptococcus , GAS) has long been regarded as being susceptible to β-lactams. However, amino acid substitutions in penicillin-binding protein (PBP)2X conferring reduced in vitro β-lactam susceptibility have been indicated since 2019 in the United States and Iceland. Here, we report the first isolation of Streptococcus pyogenes possessing the PBP2X substitution conferring reduced in vitro β-lactam susceptibility in Asia; however, the MICs were below the “susceptible” breakpoint of the CLSI.


1957 ◽  
Vol 106 (6) ◽  
pp. 777-786 ◽  
Author(s):  
Armine T. Wilson ◽  
Grove G. Wiley ◽  
Pauline Bruno

The fate of non-virulent group A streptococci phagocytized in vitro has been investigated by destroying the phagocyte with electric current and observing whether the liberated cocci multiply. Human and mouse peripheral blood neutrophils quickly injure ingested cocci, the time required to produce 50 per cent non-survival of chains being 8 and 6¾ minutes, respectively.


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