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Biomedical subjects

R Austrian

Publications and source records attributed to R Austrian.

At least 73 records · Page 4Linked to original sources
PubMed1977

Prevention of pneumococcal infection by immunization with capsular polysaccharides of Streptococcus pneumoniae: current status of polyvalent vaccines.

Because of the continuing morbidity and mortality resulting from pneumococcal infection, a program was instituted to redevelop polyvalent vaccines consisting of capsular polysaccharides of Streptococcus pneumoniae. Vaccines containing 50 microgram each of the capsular polysaccharides of as many as 13 pneumococcal types have been shown to be safe, antigenic, and 78.5% effective in the prevention of type-specific putative pneumococcal pneumonia and of type-specific pneumococcal bacteremia in adults. In a population in which pneumococcal pneumonia predominated, the total incidence of radiologically confirmed pneumonia, irrespective of cause, was reduced by 54.3% by use of a tridecavalent vaccine. The efficacy of vaccine in the prevention of infection during the first two years of life is under investigation. The vaccine is recommended for those at high risk of pneumococcal infection or of a fatal outcome from such illness.

Adult↗
PubMed1977

The bacteriology of pneumococcal otitis media.

The bacteriologic findings of 1205 episodes of pneumococcal otitis media are analyzed. Capsular types 6, 14, 19 and 23 have been found to account for more than half the initial and subsequent infections of the middle ear. Initial infection has been shown to be related to age, and recurrent infection with pneumococci of heterologous capsular types has been found to occur most often within six months of the initial attack. Nasopharyngeal carriage of the pneumococcal types most frequently causing otitis media may occur without causing infection, may antedate infection by as long as 13 months and may persist after infection for as long as 30 months. Recurrence of infection with a given capsular type has been identified following intervening infection with one or more heterologous capsular types. Simultaneous infection of the middle ear with two pneumococcal capsular types has been observed in 1% of the infections studied. The potential, but as yet unestablished, value of prophylactic vaccination against pneumococcal otitis media is considered.

Carrier State↗
PubMed1976

Pyogenic liver abscess secondary to asymptomatic sigmoid diverticulitis.

A patient with multiple pyogenic abscesses in both lobes of the liver secondary to asymptomatic sigmoid diverticulitis is presented. The rarity of this illness is noted. It is suggested that barium enema be performed in patients who present with pyogenic liver abscess of unknown etiology because of the association with asymptomatic sigmoid diverticulitis.

Colon, Sigmoid↗
PubMed1975

Spread of Streptococcus pneumoniae in families. II. Relation of transfer of S. pneumoniae to incidence of colds and serum antibody.

Factors that affect the spread of Streptococcus pneumoniae and the antibody responses associated with colonization were studied in 64 families for periods of eight to 52 weeks. Surveillance included daily recording of respiratory symptoms and bimonthly pharyngeal cultures for identification of the pneumococcal carrier state. Rhinovirus cultures were included for a portion of the study period. Intrafamilial carriage of a single type of S. pneumoniae and simultaneous spread to more than one family member were commonmspread often occurred in association with an upper respiratory tract infection; simultaneous transmission of S. pneumoniae and a rhinovirus was documented. Preexisting, type-specific serum antibody did not prevent acquisition of homotypic S. pneumoniae but did appear to shorten the duration of pharyngeal carriage. Sera of all 11 adults had greater than 150 ng of antibody nitrogen/ml of homotypic serum antibody (measured by a radioimmunoassay) before colonization. In contrast, only one of 13 preschool children had homotypic antibody concentrations of this magnitude before colonization. A threefold or greater rise in the concentration of homotypic antibody occurred in 13 of 24 children (54%) after acquisition of S. pneumoniae; the increase in antibody concentration was associated with illness in six of the children. On the other hand, acquisition of S. pneumoniae in adults was not associated with an increase in concentration of homotypic serum antibody.

Adult↗
PubMed1974

Immune response to acute otitis media in children. I. Serotypes isolated and serum and middle ear fluid antibody in pneumococcal otitis media.

Seventy percent of pneumococci isolated from the middle-ear cavity of infants and children with acute otitis media were of one of the seven serotypes 1, 3, 6, 14, 18, 19, or 23. The immunological response in the serum and middle-ear fluid from otitis media caused by one of these serotypes was studied in 61 children by using either indirect hemagglutination or indirect fluorescent antibody tests, or both. Twenty-six of the patients had pneumococcal antibody present in the acute serum and 28 had it in the convalescent serum by at least one method. Thirteen of the 49 middle-ear fluids examined had antibody by the indirect fluorescent antibody technique. Serum pneumococcal antibody was found to reside predominantly in the immunoglobulin G or immunoglobulin M classes, whereas pneumococcal antibody with middle-ear fluid was found to be distributed equally among all three classes. Approximately 25% of the patients (16 of 61) had a positive immune response to their infection as evidenced by increased levels of pneumococcal antibody in the convalescent serum. The percentage of patients responding immunologically increased with age: 12% of infants less than 12 months showed a significant response, whereas 48% of children over 24 months responded.

Age Factors↗
PubMed1973

Filamentous capsulated streptococci from the human respiratory tract. I. Antigenic attributes of provisional capsular type 83 and its relationship to streptococci of so-called group M.

Two immunologically reactive polysaccharides have been isolated from the cell walls and from culture filtrates of a filamentous alpha-hemolytic streptococcus provisionally designated capsular type 83. Both polysaccharides were purified by diethylaminoethyl-cellulose chromatography. Analysis indicates that the capsular polysaccharide consists of galactose and phosphorus, whereas the cell wall polysaccharide contains galactosamine, glucosamine, glucose, and phosphorus. On the basis of immunochemical experiments, it is suggested that the capsular polysaccharide is composed of galactose-phosphate units with terminal galactose residues at the nonreducing end. It has also been found that the capsular antigen of streptococcus type 83 is shared by a number of streptococcal strains classified in Lancefield's group M. The cell wall polysaccharide of streptococcus type 83 cross-reacts with antibody to the C(s), or cell wall-like capsular, polysaccharide of Diplococcus pneumoniae, and this cross-reactivity may be a reflection that the streptococcal antigen possesses certain structural features which are similar to those of pneumococcal C and C(s) polysaccharides.

Antigens, Bacterial↗
PubMed1973

Filamentous capsulated streptococci from the human respiratory tract. II. Antigenic structure of provisional capsular types 89 and 83-89.

Two immunologically distinct polysaccharides have been isolated from the filamentous alpha-hemolytic streptococcus of provisional capsular type 89, recovered from the human respiratory tract. Chemical analyses indicate that the capsular polysaccharide consists of glucose, galactose, and a small amount of rhamnose, whereas the cell wall-associated polymer contains galactosamine, glucosamine, glucose, and phosphorus. Immunological studies suggest that the capsular polysaccharide is type specific and that the cell wall-associated carbohydrate, which cross-reacts with the C(8), or cell wall-like capsular polysaccharide of pneumococcus, may be group specific. A noncapsulated variant of the prototypic streptococcus of provisional type 89 was shown to possess the same cell wall-associated carbohydrate as the strain from which it was derived, but it proved to be poorly antigenic in rabbits. A filamentous capsulated streptococcus reacting with antisera to filamentous streptococci of both provisional capsular types 83 and 89 has been found to produce two capsular polysaccharides, each of which reacts with antibody to one of the aforementioned unitypic strains and represents an unusual binary capsulated streptococcus.

Antigens, Bacterial↗
PubMed1973

Filamentous capsulated streptococci from the human respiratory tract. 3. Immunochemical studies of the cross-reactivity between the cell wall antigens of a filamentous streptococcus and of pneumococcus.

A cell wall-associated polysaccharide has been isolated from a noncapsulated mutant, 89R50, of the alpha-hemolytic filamentous streptococcus of provisional capsular type 89. Chemical analysis of the polysaccharide indicates that it consists of galactosamine, glucosamine, glucose, and phosphorus. Immunological cross-reactivity was observed between the streptococcal cell wall antigen and antibody to the cell wall-like capsular polysaccharide of pneumococcus. This cross-reactivity appears attributable to similarities in the teichoic acid moieties rather than in the mucopeptide moieties of the two polymers. No chemical or immunological differences were observed in the cell wall carbohydrate of the noncapsulated streptococcus, 89R50, and that of its capsulated progenitor. It is suggested that antibody to this cell wall polysaccharide might serve as a basis for grouping other filamentous strains of streptococci of diverse capsular types, the cell wall antigens of which show similar cross-reactivity with that of pneumococcus.

Antigens, Bacterial↗
PubMed1971

Capsulation of pneumococcus with soluble cell wall-like polysaccharide. II. Nonidentity of cell wall and soluble cell wall-like polysaccharides derived from the same and from different pneumococcal strains.

Methods are described for the separation of the C or cell wall polysaccharide from the C(s) or soluble C-like capsular polysaccharide of C(s) pneumococcal strains. Immunologic analysis has shown that both the C and C(s) polysaccharides of a variety of pneumococcal strains are heterogeneous and that the dissimilarities appear to reside in the mucopeptide portion of the molecule or in the region of its attachment to the teichoic acid moiety of the molecule rather than in the teichoic acid fraction. Differences of the type described have been observed in the C polysaccharides of wild-type capsulated strains of several types, in those of independently isolated noncapsulated variants derived from a single strain of a given capsular type, and in the C and C(s) polysaccharides of spontaneous mutant or transformed strains of pneumococci producing capsules of C(s) polysaccharide.

Animals↗
PubMed1970

Some biological properties of Pneumococcus type 37 and the chemistry of its capsular polysaccharide.

Pneumococcus Type 37, like pneumococcus Type 3, is characterized by the production of large mucoid colonies on the surface of solid media and by its very large capsule. It differs from the highly virulent pneumococcus Type 3 in that it is only slightly virulent for mice and rats and is isolated infrequently from man. A study of the behavior of pneumococcus Type 37 in systems comparable to those used in the study of pneumococcus Type 3 and an examination of the chemical structure of the capsule of pneumococcus Type 37 are described. The capsular polysaccharide of pneumococcus Type 37 is a viscous, optically inactive polymer composed of 95% hexose. Glucose is obtained in 88% yield upon acid hydrolysis. Periodate oxidation studies and the behavior of the polysaccharide on acid hydrolysis suggest that the molecule consists of a core of repeating units of 1,3 glucosyl-glucose to which short chains of glucose are attached at frequent intervals. Isolation of a disaccharide, the properties of which are identical with those of sophorose (beta1 --> 2 glucosyl-glucose), and of a trisaccharide are described. A tentative structure for the capsular polysaccharide of pneumococcus Type 37 is proposed.

Glucose↗
PubMed1968

Capsulation of pneumococcus with soluble C-like (Cs) polysaccharide. I. Biological and genetic properties of Cs pneumococcal strains.

Capsulated mutants of pneumococcus producing a capsule of soluble polysaccharide related immunologically to the C or cell wall polysaccharide of pneumococcus have been isolated from several noncapsulated variants of this organism. The capsular material of these strains reacts with antisera both to homologous strains and to noncapsulated strains of pneumococcus and with human C-reactive protein. C-reactive protein has been shown to give a positive capsular precipitin or Quellung reaction with C(s) pneumococcal variants and to agglutinate them. The genetic locus which determines the production of C(s) polysaccharide is situated in a region of the pneumococcal chromosome distinct from that controlling normal capsular polysaccharide synthesis. Binary and ternary capsulated pneumococci, one of the capsular components of which is C(s) polysaccharide, have been isolated following DNA-mediated transformation.

Agglutination Tests↗