Search PubMed⌕ Search

Biomedical subjects

B Kaijser

Publications and source records attributed to B Kaijser.

At least 127 records · Page 7Linked to original sources

The homogeneity of the faecal coliform flora of normal school-girls, characterized by serological and biochemical properties.

The homogeneity of fecal coliform flora in 52 schoolgirls was studied by serotyping and biotyping 10 randomly selected colonies in one fecal culture from each child. Ninety-eight clones were identified and of these 52 were dominant and 46 were minor strains. The probability of including at least one isolate of the dominant clone in a small random sample of colonies was calculated to be 86% for one colony, 94% for 2, 97% for 3, 99% for 4, and 99.3% for 5 randomly selected colonies.

Adolescent↗

Adhesion to normal human uroepithelial cells of Escherichia coli from children with various forms of urinary tract infection.

The ability to adhere to normal human uroepithelial cells was compared for Escherichia coli strains isolated from the urine of girls with acute pyelonephritis, acute cystitis, or asymptomatic bacteriuria, and from the stools of school children without bacteriuria. Strains from those with acute pyelonephritis had high adhesive ability, whereas strains from those with acute cystitis had intermediate and strains from girls with asymptomatic bacteriuria or from normal feces had low adhesive ability. Strains of serogroup O4K12 had good adherence regardless of origin. E. coli of the eight O groups commonly found in patients with acute pyelonephritis adhered more than did strains of other O groups. Spontaneously agglutinating strains had less adhesive ability than did the O-typable ones.

Acute Disease↗

Escherichia coli in bacteremia: K and O antigens and serum sensitivity of strains from adults and neonates.

Comparisons of O- and K-antigenic types and serum sensitivity were carried out with 149 strains of Escherichia coli isolated from adults with bacteremia and 46 strains from neonates with bacteremia. O-antigenic types O6, O4, O2, O16, O18, and O7 were observed most frequently, but their relative prevalence did not differ materially between adult and neonatal bacteremias. A greater proportion of strains from neonatal bacteremia contained K1 antigen and were autoagglutinable compared with strains from adult bacteremia, although K1 was the most frequent K antigen found in strains from adults. K-antigen-containing strains did not appear to be associated with enhanced severity of bacteremia, but nontypable strains, auto-agglutinable strains, and strains of O-antigenic types O4, O6, and O8 were associated with a greater frequency of shock and fatal outcome in adults. No differences could be detected between the serum sensitivities of E. coli isolated from adult bacteremia and those from neonatal bacteremia. K antigen did not affect serum sensitivity, but E. coli strains of O types O18, O2, O4, and O7 were more serum-resistant than other E. coli. Bacteremia caused by serum-sensitive E. coli was less often associated with shock and death than bacteremia caused by serum-resistant E. coli.

Adult↗

Complement activation and hematologic, hemodynamic, and respiratory reactions early after soft-tissue injury.

The effect of soft-tissue trauma was studied in dogs. Following injuries to the hind leg an aggregation of thrombocytes in blood and trapping in the lung was noted. Injury was initially followed by leukopenia and later by leukocytosis. Early hemolysis of red cells was observed. The injury was accompanied by complement activation. Its possible relation to hemolysis, leukopenia, thrombocytopenia, and increased insufflation pressure is discussed.

Animals↗

New knowledge in human milk immunoglobulin.

One of the anti-infection principles of maternal milk is the predominant milk immunoglobulin, secretory IgA. This immunoglobulin contains antibodies against many pathogens and potential pathogens, viruses as well as bacteria, including several members of Enterobacteriacae. The antigenic stimuli for these milk antibodies seem to take place in the Peyer's patches of the intestine. Lymphoid cells leaving the patches after antigenic exposure seem to home to the mammary glands via the lymph and blood circulation. As a result, the milk contains secretory IgA antibodies against, among other things, the intestinal bacteria of the mother. These milk antibodies might reflect the spectrum of bacteria and viruses in the community and may be important for the protection of the breast-fed baby. Via the same homing mechanism the maternal milk obtains antibodies against dietary antigens, including cow's milk proteins. Studies of infants on mixed feeding suggest that the secretory IgA antibodies against the bovine proteins diminish the antigenic exposure, indicating the possibility of an anti-allergic mechanism.

Antibody Formation↗

Protection against experimental Proteus mirabilis pyelonephritis in rats and significance of immunity.

Intraperitoneal immunization with formalin-killed bacteria as well as previous hematogenous infection with Proteus O3H1 showed a protective effect against hematogenous pyelonephritis in rats when the homologous strain was used. Transfer of hyperimmune antisera protected against hematogenously induced infection. Neither intravesical or intraperitoneal immunization with formalin-killed bacteria nor transfer of urines containing antibodies of the IgG class protected against ascending pyelonephritis when the O3H1 strain was used. Data are presented indicating that a rise of pH might decrease the biological effect of antibodies, suggesting that Proteus urease activity is a virulence factor of importance in this context.

Animals↗

Protection against ascending Escherichia coli pyelonephritis in rats and significance of local immunity.

Acute pyelonephritis in rats caused by Escherichia coli O6K13H1 produced serum and urinary antibodies against O6 and K13 antigens. This was also seen after intravesical immunization with Formalin-killed bacteria. Both intraperitoneal and intravesical immunization with these Formalin-killed bacteria protected against ascending urinary tract infection induced by homologous bacteria. Passive transfer of urine containing both O6 and K13 antibodies also protected against infection. By absorption experiments it was shown that K13 antibodies were especially important.

Animals↗

Interaction of human serum and neutrophils with Escherichia coli strains: differences between strains isolated from urine of patients with pyelonephritis or asymptomatic bacteriuria.

Strains of Escherichia coli isolated from the urine of children with pyelonephritis (n = 18) or asymptomatic bacteriuria (ABU) (n = 20) were serotyped and compared with respect to opsonic requirements, sensitivity to serum, amount of chemiluminescence produced by normal neutrophils during phagocytosis of the various strains, and amount of capsular antigen. Strains isolated from cases of ABU more often had the capacity to activate the alternative complement pathway than had strains causing pyelonephritis. The ABU strains were also better opsonized in fresh human serum and were more often serum sensitive than the pyelonephritic strains. There were individual variations in neutrophil chemiluminescence during phagocytosis of the various strains, but the two groups of strains did not differ significantly. The strains from pyelonephritis cases produced a greater amount of capsular antigens than the ABU strains. There was no correlation between presence of a particular O or K antigen and capacity to activate the alternative complement pathway. The observed differences between strains isolated from patients with ABU and those isolated from patients with pyelonephritis may be relevant for further studies on differences in bacterial virulence or host defense factors.

Antigens, Bacterial↗

Serological diagnosis of pneumococcal disease with enzyme-linked immunosorbent assay (ELISA).

Antibody response to pneumococcal type-specific polysaccharide was measured with enzyme-linked immunosorbent assay (ELISA). The test was shown to be up to 500 times more sensitive than indirect hemagglutination using chromic chloride-treated red blood cells. In 16/17 patients with pneumococcal pneumonia a significant antibody increase was seen as measured with ELISA. Only 6/23 patients with pneumonia caused by Mycoplasma pneumoniae gave a pneumococcal antibody rise and in those cases the increase was very slight. The authors consider ELISA a valuable contribution to the serological diagnosis of pneumococcal disease.

Adult↗

High frequency of K15 antigen in enterotoxigenic Escherichia coli: lack of correlation to adherence to epithelial cells or sensitivity to bactericidal effect of normal serum.

Typing of E. coli O and K antigens, testing of sensitivity to bactericidal effect of normal serum and adherence to uroepithelial as well as buccal epithelial cells was performed in enterotoxinogenic (ETEC) and normal E. coli strains. The 99 ETEC faecal strains were obtained from Swedish and Ethiopian children and adults and Swedish soldiers in Cyprus with diarrhoea. The reference faecal strains were isolated from 120 healthy Swedish children. E. coli K15 was significantly more often seen in ETEC strains than in the reference strains, always in combination with O6 antigen. K15 is hardly ever seen in nonenterotoxinogenic strains. There was no significant difference in sensitivity to bactericidal effect of serum or adherence to epithelial cells between ETEC strains and normal strains. The epidemiological significance of the findings is discussed.

Adult↗

Frequency of E. coli K antigens in urinary-tract infections in children.

The somatic (O) and casular (K) antigens of Escherichia coli from the urine of patients with acute pyelonephritis, acute cystitis, and asymptomatic bacteriuria, and in the faeces of healthy schoolchildren have been investigated. Typing antisera for sixteen capsular acidic polysaccharide K antigens were used, and five (numbers 1, 2, 3, 12, and 13) accounted for 70% of isolates from patients with acute pyelonephritis. These five K antigens were found to a lesser extent in the three other study groups. Thus, only a few K polysaccharides are associated with virulent properties of E. coli for the upper urinary tract. This finding is similar to the association of only some capsular types of pneumococci, meningococci, and Haemophilus influenzae with invasiveness. The identification of virulence markers for E. coli associated with upper-urinary-tract disease may permit more successful control with reference to preventive immunisation.

Acute Disease↗

Significance of antibody-coated bacteria in urinary sediment in experimental pyelonephritis.

The sequential appearance of antibody-coated bacteria in urinary sediment was followed in experimental pyelonephritis produced with Escherichia coli O6:K13:H1. It was possible to determine against which antigen of the organism this antibody was directed. Antibody-coated bacteria appeared by day 11 of infection, a time which coincided with the synthesis of local (intrarenal) antibody. Bacteria coated with antibody more than three days after serum antibody but four days before urinary antibody appeared. Antibody eluted from coated bacteria was directed against the O-antigen of the infecting organism but not the K-antigen. Newly synthesized intrarenal antibody and urinary antibody were directed only against O-antigen, but not against K-antigen; this finding would explain why the antibody that coated the bacteria was antibody to lipopolysaccharide. Thus, a positive test for antibody-coated bacteria indicates that a local immune response to O-antigen has occurred. It is postulated that this immune response could relate to the clinical symptomatology of acute symptomatic pyelonephritis since most patients presenting with acute pyelonephritis have bacteria coated with antibody.

Animals↗

Comparison of Escherichia coli from bacteriuric patients with those from feces of healthy schoolchildren.

The properties of 709 strains of Escherichia coli isolated from feces of healthy schoolchildren were compared with those of 115 strains from the urine of girls with asymptomatic bacteriuria (ABU) detected in a screening program. These fecal strains were also compared with 45 strains that caused asymptomatic reinfections and 10 that caused symptomatic reinfections in the same group of girls. Typing of O antigen was done by direct bacterial agglutination, and K typing was done with a serum agar technique. Hemolytic capacity was assessed in solid medium. Sensitivity to the bactericidal effect of normal serum and minimal inhibitory concentrations of ampicillin were also determined. The strains isolated from girls who had reinfections of ABU were found to be a random sample of the fecal flora, but the strains from children with symptomatic reinfection were not. Strains from index patients with ABU differed from the other groups in a way that was indicative of adaptive changes in the structure of cell envelopes.

Adolescent↗

Antigens of Escherichia coli, human immune response, and the pathogenesis of urinary tract infections.

Acute pyelonephritis (but not cystitis or "asymptomatic" bacteriuria) due to Escherichia coli induces serum antibodies to O-but rarely to K-antigens, especially not to the most common antigen, K1. Locally produced secretory IgA and IgG antibodies to O-and K-antigens appear in urine during most infections. The E. coli in urine of patients with asymptomatic bacteriuria are different from those in patients with acute pyelonephritis and cystitis and undergo continuous changes, presumably caused by the local antibody response. The E. coli become less virulent and are less able to attach to uroepithelial cells than E. coli causing acute symptomatic infections. Antibodies in urine prevent epithelial adherence. Parenteral and intravesicular injections of killed bacteria can protect against ascending pyelonephritis in rats. A few K-antigens dominate among E. coli that cause urinary tract infections. Vaccination of problem cases is a possibility because of the protective nature of K-antibodies. The mechanism of renal scarring that appears in some patients with urinary tract infections is unknown. Autoantibodies to the Tamm-Horsfall protein that increase after acute pyelonephritis or the cross-reactions noted between certain E. coli and antigens on the kidney may be involved.

Animals↗

Neonatal meningitis due of Escherichia coli K1.

Human neonates are uniquely susceptible to serious infections due to Escherichia coli. Investigation of the serotypes of E. coli isolated from neonates with meningitis revealed that greater than 80% of the isolates possessed the capsular polysaccharide antigen designated K1. Cultures of stool from healthy infants, children, and adults have shown that K1 organisms are commonly found in individuals of all ages. Studies of mother-infant pairs have demonstrated transmission of K1 strains from mother to infant shortly after birth. In the rare infant who develops meningitis due to E. coli K1, serotype analysis frequently reveals that the same organism was isolated from the infant's cerebrospinal fluid and from the stools of both mother and infant. Preliminary investigations of humoral immunity demonstrated an age-related acquisition of antibodies to the capsular polysaccharide of E. coli K1 in healthy infants and children. An animal model was developed in which feeding of E. coli K1 to infant rats resulted in colonization, bacteremia, and meningitis in the animals.

Adult↗

Characteristics of antibiotic-resistant Escherichia coli in the rectum of healthy school-children.

During a 3-year period, 771 rectal swabs were taken from abacteriuric school-children. Out of 709 E. coli strains, each isolated from one faecal specimen, 102 were found to be resistant to one or more antibacterial agents, and 607 to be fully sensitive. Another 204 resistant strains were found by selection for antibiotic resistance. The antibiotic-sensitive and the resistant strains were found to be two somewhat different populations, distinguished by a different distribution of O antigen types. Also, the K1 antigen was more common among the sensitive than among the resistant strains. Resistant strains that were not O typable were very seldom haemolytic.

Adolescent↗