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C J Baker

Publications and source records attributed to C J Baker.

At least 253 records · Page 14Linked to original sources
PubMed1976

Antimicrobial susceptibility of group B streptococci isolated from a variety of clinical sources.

The minimal inhibitory concentration of 10 antibiotics for 244 isolates of group B streptococci was determined. Susceptibility to penicillin G, ampicillin, cephalothin, chloramphenicol, and carbenicillin was uniform. Tetracycline and bacitracin resistance among these isolates was frequent (87.5 and 97.9%, respectively). Three strains (1.2%) failed to be inhibited by 100 mug of lincomycin or clindamycin per ml. Susceptibility of these 244 strains to the agents tested was unrelated to source of the isolate, year of isolation, or strain serotype. No apparent change in the suceptibility of group B streptococci to penicillin G has occurred during the past 2 decades.

Anti-Bacterial Agents↗
PubMed1976

Microcapsule of type III strains of group B Streptococcus: production and morphology.

The yield of purified type III polysaccharide of group B Streptococcus was significantly improved by modification of the growth medium. Culture of organisms in standard Todd-Hewitt broth resulted in acid accumulation during the exponential phase of growth and poor yield of type III polysaccharide when extracted from cells by washing with neutral buffer solution. By increasing the buffering capacity of the broth medium, acid accumulation was prevented, and the number of viable cells was increased at the stationary phase of growth. Further, by increasing the concentration of glucose in the buffered medium, the yield of type III polysaccharide was increased two to three times. Electron microscopic investigations of cells grown in the modified broth medium demonstrated a thicker microcapsule than was found in organisms grown in standard broth.

Cell Wall↗
PubMed1976

Identification of sialic acid in polysaccharide antigens in group B Streptococcus.

By means of paper chromatographic techniques with purified, sialic acid-containing, bacterial antigen standards, sialic acid, as well as galactose and glucosamine, have been identified as components of each type-specific antigen of group B Streptococcus. Rhamnose was not detected in the group B antigen isolated by the classical HCl and heat extraction method.

Antigens, Bacterial↗
PubMed1976

Comparison of bacteriological methods for the isolation of group of B Streptococcus from vaginal cultures.

Three bacteriological techniques for the isolation of group B streptococci in vaginal cultures were compared. A selective broth medium (SBM) containing gentamicin and nalidixic acid was more sensitive for the detection of vaginal isolates (28/76, 36.8%) from 76 women enrolled in a venereal disease clinic than was an identical selective plate medium (SPM) (17/76, 25%). Similarly, SBM allowed identification of positive cultures from college women (82/459, 17.9%) significantly more often than direct inoculation of swabs onto nonselective blood agar medium (43/460, 9.4%; chi2 = 42.2, P = less than 0.001). Failure to isolate group B streptococci detected in SBM occurred in 32.1% cultures by SPM and 49.4% of cultures by nonselective agar medium. Multiple serotypes were detected in a single vaginal culture from approximately 5% of the patients studied. These data support the routine use of SBM for the most accurate identification of women vaginally colonized with group B Streptococcus.

Bacteriological Techniques↗
PubMed1975

The influence of advancing gestation on group B streptococcal colonization in pregnant women.

An investigation to determine the throat and vaginal colonization rates of group B streptococci among second- and third-trimester pregnant women was performed. Group B streptococci were recovered from 25.4 per cent of third-trimester and 14.8 per cent of second-trimester parturient (p = less than 0.025). Serotype distribution of isolates was similar among these two study groups. No significant differences in colonization rates were noted on the basis of age, race, parity, or complications of pregnancy.However, postpartum fever occurred in 22 per cent of colonized and only 4 per cent of noncolonized second-trimester parturients. The reason for this significant increase in group B streptococcal colonization rates with advancing gestation remains speculative.

Abortion, Spontaneous↗
PubMed1974

Incidence of kanamycin resistance among Escherichia coli isolates from neonates.

The antimicrobial susceptibilities of 368 E. coli strains isolated from well neonates, well pediatric outpatients, and ill neonates were determined, and the incidence of antibiotic-resistant strains was correlated with epidemiologic data. Ninety-five per cent of these isolates were susceptible to kanamycin and 98 per cent to gentamicin. Most of the difference in susceptibility of these E. coli strains to kanamycin and gentamicin appeared to be on the basis of weight for weight activity. Kanamycin-susceptible strains were isolated from 96 per cent of well neonates and well outpatients, and 94 per cent of ill neonates, age three days or less. An increase in the incidence of resistance to kanamycin, streptomycin, and ampicillin among strains isolated from neonates was related to prolonged hospitalization and/or prior antibiotic therapy. This study demonstrates the need for analyzing antimicrobial susceptibility data from newborn nurseries in an epidemiologic context.

Child↗
PubMed1973

Selective broth medium for isolation of group B streptococci.

A selective medium containing Todd-Hewitt broth, sheep blood, nalidixic acid, and gentamicin sulfate was found to enhance significantly the isolation of group B streptococci from vaginal cultures. Preparation of the medium, which is stable for up to 4 weeks at 4 C, is simple and inexpensive. Use of such a medium should facilitate identification of vaginal colonization with group B streptococci.

Animals↗