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Biomedical subjects

L W Wannamaker

Publications and source records attributed to L W Wannamaker.

At least 37 records · Page 2Linked to original sources
PubMed1981

Cellular immune responses to extracellular streptococcal products in rheumatic heart disease.

The lymphocyte transformation responses to purified preparations of two extracellular products of group A streptococci (blastogen A and nuclease B), to phytohemagglutinin, and to Candida albicans antigen were measured in tonsillar and peripheral blood lymphocytes from patients with rheumatic heart disease (RHD) and suitably matched nonrheumatic (control) subjects. The mean phytohemagglutinin dose responses of tonsillar and peripheral lymphocytes from RHD patients were essentially indistinguishable from those of controls. In contrast, the responses of tonsillar and peripheral blood lymphocytes to the two extracellular products of group A streptococci were significantly lower in RHD patients than in nonrheumatic control subjects. Candida antigen produced very little stimulation of lymphocytes in any of the subjects. The geometric means of antibody levels against streptolysin O, nuclease B, and nicotinamide adenine dinucleotidase showed no consistent differences between the control group and the group of RHD subjects. Group A streptococci were isolated from the tonsils of approximately 25% of both groups of subjects. The RHD patients clearly had a depressed cellular immune response to the two purified streptococcal extracellular antigens. The equal frequency in recovery of group A streptococci from tonsils and the absence of consistent difference in titers of humoral antibodies to streptococcal extracellular antigens, particularly nuclease B, suggest that this differential response is not due to a lower level of stimulation by repeated exposure to group A streptococcal products.

Antigens, Bacterial↗
PubMed1980

Failure of penicillin to eradicate group A streptococci during an outbreak of pharyngitis.

In an outbreak of group A streptococcal pharyngitis in a semi-closed community, 42 (25%) of 169 courses of antibiotic therapy failed to eradicate the organism. 16 (19%) of 85 individuals treated with intramuscular benzathine penicillin G and 9 (19%) of 47 patients treated with an oral antibiotic (penicillin V or erythromycin) continued to harbour the same serotype of group A streptococcus. 12 (48%) of 25 persons remained treatment failures after re-treatment; even after a third course of treatment 5 of 12 (42%) still harboured the organism. Neither antibiotic resistance of the epidemic strain nor reacquisition of the organism from contacts could be implicated as causes. The data suggest that many who did not respond to treatment were streptococcal carriers and raise the possibility that it is more difficult to eradicate the organism from the carrier than from the acutely infected individual.

Adult↗
PubMed1980

Biochemical and immunological characterization of the extracellular nucleases of group B streptococci.

Nearly all group B streptococcal strains representing the five major serotypes were found to produce extracellular nucleases by screening with an agar-well-diffusion technique in DNA-methyl green agar plates. Three different nucleases have been isolated and partially purified by DEAE-and carboxymethyl-cellulose chromatography. They possessed different mobilities on polyacrylamide gel electrophoresis and different molecular weights. These nucleases, designated I, II, and III, are optimally activated by cations of calcium and manganese and exhibited RNase as well as DNase activity. Despite differences in their physical and biochemical properties, nucleases II and III appear antigenically similar, but distinct from nuclease I. These group B streptococcal nucleases are immunologically different from the nucleases of group A streptococci. Neutralizing activity, probably antibody, to nucleases II and III was found in human sera, and was most prevalent in sera of pregnant women colonized with group B streptococci and in their newborn infants.

Bacterial Proteins↗
PubMed1980

The immunologic response to group A streptococcal upper respiratory tract infections in very young children.

The immunologic responses to streptolysin O and streptococcal deoxyribonuclease B were evaluated in children with group A streptococci recovered from the upper respiratory tract to re-examine the hypothesis that a limited capacity to respond to group A streptococcal infection may explain the rare occurrence of acute rheumatic fever in very young children. ASO and anti-DNase B titers were determined on serial bleedings from a total of 301 individuals (52 less than or equal to 3 years; 249 older than 3 years). Very young children with group A streptococcal upper respiratory tract infections had an immunologic response to SO greater than the response in older children as reflected by the magnitude of the antibody rise, and comparable to the ASO response in older children as measured by the percentage showing a significant titer rise. Similar analyses of the anti-DNase B responses showed the response in young children to be comparable to those of the older group. Clinical manifestations of group A streptococcal upper respiratory tract infection in very young children differ from those observed in older children and have not changed significantly in the past several decades. These data suggest that the infrequent occurrence of acute rheumatic fever in very young children is not due to a difference in antibody response to streptolysin O or streptococcal DNase B.

Adolescent↗
PubMed1980

A controlled study of penicillin therapy of group A streptococcal acquisitions in Egyptian families.

A two-year controlled trial of benzathine penicillin G treatment of persons who acquired group A streptococci, identified by semimonthly throat cultures, was carried out in Egypt in 110 apparently normal families and 84 families with a child suspected of having rheumatic heart disease. Penicillin treatment was associated with a marked decrease in prevalence of the organism (19.0%-5.4%) and a modest decrease in introductions into families (0.79-0.54 single introductions per person per year) but no decrease in spread within nonrheumatic families. Results in suspected-rheumatic families were similar. It was concluded that the schedule of penicillin treatment used had a minimal effect on streptococcal spread and is unlikely to be an effective control tool. Spread within families was most intense in those episodes in which the household contacts were two to 14 years of age, the introducer had sought medical care, or the introducer ultimately carried the streptococcal strain for three or more months.

Egypt↗
PubMed1980

Susceptibility of group A streptococci to oleic acid and ultraviolet light. Comparison of strains from throat and skin.

Group A streptococcal strains of some serotypes can be cultured repeatedly from normal human skin for days or weeks and subsequently produce pyoderma, but strains of other serotypes that cause pharyngitis are rarely recovered from normal human skin or skin lesions. In an attempt to understand the biological differences between "skin" and "throat" strains of group A streptococci, we studied their susceptibility to two bactericidal agents operative at the skin surface--oleic acid and UV light. No consistent differences were found between skin and throat strains; all streptococcal strains were exquisitely sensitive to both oleic acid (10 microgram/ml) and UV light (60 microW/cm2).

Microbial Sensitivity Tests↗
PubMed1979

Immunological properties of hyaluronidases associated with temperate bacteriophages of group A streptococci.

The antigenic relationships of hyaluronidases, bound and free, associated with temperate bacteriophages of group A streptococci were examined with antibody against purified whole phage and with antibody against phage-bound enzyme released by urea and purified to homogeneity. Studies performed by double diffusion in agar (ouchterlony) with antibody against the homologous purified enzyme from a temperate phage of a type 49 streptococcus indicated that the bound and free enzyme gave a single line of identity and that the free hyaluronidase activities in induced lysates of four strains of M type 49 streptococci were immunologically indistinguishable but different from the enzyme in induced lysates of a heterologous type. The four M type 49 strains were from widely different geographical or temporal sources and of different phage subtypes as determined by lyxic patterns. These findings were confirmed in studies that employed a functional assay of enzyme neutralization. An immunoglobulin preparation of antiserum against the purified enzyme as well as one against homologous purified whole phage neutralized the hyaluronidase activity produced by induction of the M type 49 strains and present either phage-bound or soluble in phage-free lysates. These immunoglobulin preparations had little effect on the hyaluronidase activities present in phage-lysates of other M types of group A streptococci. Inhibition of propagation of temperate phages by antibody against the purified phage hyaluronidase paralleled the neutralization of phage-associated enzyme activity by this antibody, indicating that antibody to the purified enzyme can inhibit phage infection. Antibody preparations against the purified phage-bound enzyme or against purified whole phage did not neutralize the extracellular hyaluronidase in the supernate of an uninduced culture of M type 4 streptococci. A human serum strongly inhibitory for the extracellular enzyme of this strain or on the purified phage enzyme from an M type 49 strain. The results support the view that the hyaluronidases associated with the temperate bacteriophages from various M types of group A streptococci do not share common antigenic determinants but that an immunological specificity exists that parallels the serologic specificity of the M protein of the host strains.

Antibody Specificity↗
PubMed1979

Production of a bacteriocine-like substance by group-A streptococci of M-type 4 and T-pattern 4.

A unique and characteristic bacteriocine-like inhibitor elaborated by M-type 4, T-pattern 4, group-A streptococci was isolated and partially purified. This inhibitor was found to be produced optimally in Todd-Hewitt broth; after extraction and concentration, was shown to be protein in nature, and to have a m.w. of c. 8000. It was extremely heat stable and acid tolerant, but was quickly inactivated in alkaline conditions. It could be demonstrated in cell-bound form, but 99.5% was found in culture supernates. It was specifically adsorbed by viable sensitive cells, and its mode of action was bacteristatic.

Antigens, Bacterial↗
PubMed1979

Bactericidal effect of oleic acid on group A streptococci: mechanism of action.

In contrast to Staphylococcus aureus and coagulase-negative staphylococci, group A streptococci are infrequently present on normal human skin, except in certain populations with endemic impetigo. This has been attributed to differences in susceptibility to the bactericidal effect of skin surface lipids, particularly unsaturated fatty acids. When an M type 6 strain group A streptococcus was exposed to 500 mug of oleic acid per ml, viable counts decreased by 4 logs in 5 min. The rank order of killing was 35 > 20 > 4 degrees C. Oleic acid did not kill a strain of S. aureus, a strain of coagulase-negative staphylococcus, or a strain of Escherichia coli, but bound rapidly to these bacteria as well as to the group A streptococcus. The loss of [(3)H]uridine from labeled oleic acid-treated group A streptococcal cells was greater than 100 times that of controls. There was no loss of [(3)H]-thymidine from group A streptococci or of [(3)H]uridine or [(3)H]thymidine from identically exposed coagulase-negative staphylococci. When [(3)H]uridine was added to group A streptococci during mid-log-phase growth, cessation of uptake occurred within 5 min of addition of 50 mug of oleic acid per ml. Electron microscopic changes seen within 5 min included condensation of the nucleoid and distortion of the streptococcal surface by numerous clumps and blebs. Coagulase-negative staphylococci, S. aureus, and E. coli similarly exposed showed no comparable electron microscopic changes. We propose that oleic acid kills group A streptococci by altering the integrity of the cell membrane with resulting loss of ribonucleic acid but not deoxyribonucleic acid.

Escherichia coli↗
PubMed1978

Studies on streptococci resembling Streptococcus milleri and on an associated surface-protein antigen.

Ninety-nine strains of streptococci were isolated from 97 cases of pyogenic infections, most of which involved the teeth. Physiological and serological tests were performed on these streptococci and on 37 strains of streptococci from culture collections. The results were used for a numerical classification. Seventy-nine of the strains isolated from patients formed a cluster with Streptococcus milleri and group-F reference strains, and were therefore considered as streptococci resembling S. milleri. By the use of an antiserum prepared against strain Z3, protein antigens were demonstrated in acid extracts of 65% of the strains of S. milleri. These antigens were in only five strains not included in the S. milleri cluster.

Antigens, Bacterial↗
PubMed1978

Streptococcin A-FF22: nisin-like antibiotic substance produced by a group A streptococcus.

Streptococcin A-FF22 (SA) was shown to occur as both a cell-associated (SA-CA) and an extracellular (SA-EX) component of cultures of the producer bacterium, group A streptococcus strain FF22. SA-CA was solubilized by chemical, enzymatic, and mechanical procedures, similar to those used to release M protein. The independence of SA and M protein in strain FF22 was established by chromatographic separation of the two proteins on the basis of molecular weight and isoelectric point differences between the two substances. Media supporting optimal growth of strain FF22 did not necessarily favor SA production. SA was not produced either at elevated temperatures (39 degrees C) or if the culture was maintained at pH 7 or higher. The release of SA from producer cells was enhanced at lower culture pH values. Much of the SA-CA activity seemed associated with the cell walls of the producer strain, and the nature of the binding appeared to be largely nonspecific in nature and attributable to electrostatic interaction.

Anti-Bacterial Agents↗
PubMed1978

Dynamics of Escherichia coli infection and meningitis in infant rats.

Escherichia coli strains isolated from newborn infants were injected intraperitoneally into infant rats. Strains possessing the K1 capsular polysaccharide antigen were significantly more virulent than strains lacking this antigen. When 5-day-old animals were injected with 1.2 X 10(1) colony forming units of a K1 E. coli strain (serotype O18ac:K1:H7), about 80% had bacteria isolated from their blood. Forty-eight percent of bacteremic animals had positive cerebrospinal fluid cultures. The development of bacteremia with greater than 10(4) colony-forming units per ml of blood correlated with positive cultures of cerebrospinal fluid. Some animals, studied with serial blood cultures, were able to clear bacteria spontaneously from their blood, whereas others succumbed to infection within 48 h of challenge. The susceptibility of infant rats to E. coli infection was age dependent and appeared related to the K1 antigen.

Age Factors↗
PubMed1978

Purification and characterization of a hyaluronidase associated with a temperate bacteriophage of group A, type 49 streptococci.

Urea treatment of a temperate bacteriophage from a type 49 strain of group A streptococcus (Streptococcus pyogenes) followed by ammonium sulfate fractionation, ion exchange, and affinity chromatography of solubilized proteins provided for the recovery (12%) and purification (44-fold) of the phage-associated hyaluronidase. The molecular weight of the homogeneous, purified enzyme was estimated to be 71,000 by polyacrylamide gel electrophoresis (in the presence of sodium dodecyl sulfate) and 75,000 by gel filtration with Sephacryl S-200. The enzyme has a pH optimum of 5.5, a Vmax of 0.1 absorbance unit/min per microgram of protein, and a Km of 4.8 X 10(-2) mg/ml with umbilical cord hyaluronic acid as substrate. Of the cations tested, calcium and magnesium were the only effectors of the enzyme. The enzyme is a glycoprotein (7.25% carbohydrate) containing glucose, galactose, and glucosamine. Analysis of the amino acid composition revealed a predominance of acidic amino acids and a relatively high content of cysteine. The partial specific volume, estimated from the amino acid and sugar analyses, was 0.725 cm3/g.

Amino Acids↗