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Biomedical subjects

L W Wannamaker

Publications and source records attributed to L W Wannamaker.

At least 109 records · Page 6Linked to original sources
PubMed1970

Effect of Bactericidal Substance from Staphylococcus aureus on Group A Streptococci I. Biochemical Alterations.

A bactericidal substance isolated from phage type 71 staphylococci has been studied relative to its mechanism of action on streptococcal cells. The substance exerts its effect best at 37 C. No cell lysis occurs as evidenced by lack of alteration in optical density of susceptible cell suspensions. The bactericidal substance results in immediate cessation of protein and deoxyribonucleic acid synthesis as well as degradation of newly and previously formed ribonucleic acid (RNA). The action on RNA seems to be independent of protein synthesis.

Journal Article↗
PubMed1970

The influence of the site of infection on the immune response to group A streptococci.

The immune response after streptococcal infection of the skin and of the upper respiratory tract (URT) was studied prospectively in a group of normal children, ages 3-6 yr. The children were examined and cultures for group A streptococci were obtained weekly from the throat, nose, and skin lesions (when present). Paired sera were collected at the beginning and end of the study, and the changes in antibody titers were measured for three different streptococcal antigens: streptolysin O, deoxyribonuclease B (DNAse B), and nicotinamide adenine dinucleotidase (NADase). The findings suggest that in contrast to infection of the URT antibody response to streptolysin O is relatively feeble after streptococcal infection which is limited to the skin. The response to NADase is also poor after cutaneous infection. Antibody responses to DNAse B are generally good regardless of the site of the infection. These and other studies indicate that anti-DNAse B is the antibody of choice in studying streptococcal infection of the skin and its complications.

Antibody Formation↗
PubMed1969

Demonstration of a bactericidal substance against beta-hemolytic streptococci in supernatant fluids of staphylococcal cultures.

Staphylococcal skin isolates belonging to phage type 71 were found to produce a bactericidal substance against some streptococci, pneumococci, and corynebacteria. Fifteen strains of group A streptococci belonging to 13 different M types, group C streptococci, and group D streptococci were uniformly inhibited on solid media and in broth by membrane-filtered supernatant fluids of the staphylococcal broth cultures. Inhibition of group G streptococci and other staphyloccoci was variable, and no inhibition of group B streptococci or of a variety of gram-negative rods was demonstrable. A quantitative variation observed to exist among susceptible organisms was a function of the inoculum size of the inhibited strains. The bactericidal substance could be detected best from 24 to 48 hr after inoculation of the staphylococci in tryptic soy broth or in a dialysate of tryptic soy broth. Little or no bactericidal activity was noted when the organisms were grown in several other liquid media. The bactericidal substance was nondialyzable and could be precipitated with ammonium sulfate. It was heat-stable and its activity was not altered within a pH range of 4.0 to 8.5. Pronase and three times crystallized trypsin totally abolished its activity. The concentrated ammonium sulfate precipitate could be fractionated on a Sephadex G-100 column into several peaks, with the bactericidal activity localized to a single peak.

Anti-Bacterial Agents↗
PubMed1969

Attack rates of acute nephritis after type 49 streptococcal infection of the skin and of the respiratory tract.

Prospective studies in a population of American Indian children during an outbreak of acute nephritis associated with the Type 49 Group A streptococcus permitted a comparison of attack rates of renal complications after infection at different sites and at different ages. Acute nephritis or unexplained hematuria developed in 10 of 42 children (23.8%) with Type 49 streptococcal skin infection, in 2 of 44 (4.5%) with Type 49 throat infection, and in 3 of 16 (18.8%) with simultaneous Type 49 infection at both sites. The higher attack rate of nephritis and hematuria in children with pyoderma indicates that skin lesions played a direct and quantitatively greater role than respiratory infection in the pathogenesis of acute nephritis during this outbreak. Skin infections with the Type 49 strain were followed by evidence of renal complications more often in children younger than 6.5 yr (9 of 21 or 43%) than in older children (1 of 21 or 5%). Attack rates of renal complications after Type 49 skin infection were approximately equal in males and females.

Acute Disease↗
PubMed1968

The serum opacity reaction of Streptococcus pyogenes. The demonstration of multiple, strain-specific lipoproteinase antigens.

Investigation into the antigenicity of streptococcal lipoproteinase has revealed the existence of multiple, immunologically distinct enzymes. Each lipoproteinase identified was found to be strain specific in that it was found only in strains of a particular T-agglutination pattern. In some T patterns, all streptococci of that T pattern which were examined shared a common lipoproteinase antigen. In other T patterns, strains which produced antigenically different lipoproteinases were identified. Evidence that the lipoproteinase antigen is distinct from other well-established cellular antigens of Group A streptococci has been presented. The production of this strain-specific enzyme by strains currently difficult to type by the standard M precipitin method may facilitate more precise identification of these strains and a better assessment of their role in the pathogenesis of Group A streptococcal infections and their sequelae.

Animals↗
PubMed1967

M antigens among group A streptococci isolated from skin lesions.

Three new provisional types of Group A streptococci have been identified among strains isolated from skin infections of American Indian children. A previously established type, Type 41, was also recognized among the pyoderma strains. Most of the skin streptococci with T-agglutination pattern 3/13/B3264 could be identified as Type 41 or as one of two new provisional types, Schoenborn (Type 52) and Hanson (proposed Type 53). Strains of the third new provisional type, Kingbird (proposed Type 54), agglutinated as 15/17/19/23/47, a T pattern not associated with skin infections in studies of other populations. Approximately half of the pyoderma strains examined were found to produce an M antigen; the proportion of M-typable strains from skin infections was found to be similar to that currently found in throat cultures of children with pharyngitis. The demonstration of M antigens in streptococci from skin lesions provides evidence of their potential virulence and should facilitate their classification in subsequent epidemiological studies.

Agglutination Tests↗
PubMed1967

Streptococcal nucleases. I. Further studies on the A, B, and C enzymes.

Streptococcal DNAse C is more resistant to heat inactivation than the A or B enzyme. DNAses A and C are indifferent to the bacterial ribonucleic acid inhibitor whereas the B enzyme is markedly inhibited. Prolonged digestion with relatively large amounts of DNAse B results in chemical and biological destruction of the inhibitor. Ribonuclease as well as deoxyribonuclease activity is associated with the B enzyme. Both activities require divalent cations and both are inhibited by bacterial ribonucleic acid. The ratios of the two activities are constant in various preparations and after partial heat inactivation. Mutual inhibition of the two activities can be demonstrated in mixed substrate systems. The evidence presented is consistent with the view that the B enzyme is a single nuclease which can attack both deoxyribonucleic and ribonucleic acids.

Calcium↗
PubMed1967

Streptococcal nucleases. II. Characterization of DNAse D.

Preparations of streptococcal DNAse D with high specific activity and free of other streptococcal nucleases have been obtained by zone electrophoresis and column chromatography. Antisera prepared by injecting rabbits with such preparations specifically neutralize the activity of this enzyme. As with DNAse B, preparations of DNAse D regularly exhibit ribonuclease activity. For both B and D enzymes, the order of substrate preference is thymus DNA, yeast RNA, bacterial RNA; but the specific activity of the D enzyme is higher than that of the B enzyme with respect to thymus DNA and lower with respect to bacterial RNA. Both the deoxyribonuclease and the ribonuclease activities exhibited by preparations of both enzymes are inhibited by bacterial RNA, but approximately 100-fold greater concentrations of bacterial RNA are required to achieve inhibition of the deoxyribonuclease activity of the D enzyme equivalent to the inhibition of the B enzyme. The deoxyribonuclease activity of the D enzyme is also inhibited by yeast RNA, but even larger amounts are required. These observations indicate that the D enzyme is immunologically distinct from the other streptococcal nucleases and that it differs quantitatively from the B enzyme with respect to relative specific activities on different substrates and behavior in the presence of the bacterial ribonucleic acid inhibitor.

Citrates↗