摘要:

376 sera from Norwegian kidney‐transplant recipients and their living, related donors, were tested for the presence of cytomegalovirus antibodies (CMV‐ab) by the complement fixation test (CF), and for IgG CMV‐ab by the enzyme‐linked immuno‐sorbent assay (ELISA). Whenever the results of the two methods differed, the sera were also tested by the indirect fluorescence antibody test (FAT). 325 of 376 sera showed corresponding results, giving a concordance of 86 per cent between CF and ELISA, ELISA being the more sensitive of the two, with a sensitivity in the same range as FAT, and high specificity with only 0.3 per cent false positive results. The prevalence of CMV‐ab in Norwegian kidney‐transplant recipients and their living, related donors, differed very little. The overall CMV‐ab seropositivity was 76 per cent. The prevalence increased from 50 per cent at the age of 20 years, to 80 per cent at 30 years and 90 to 100 per cent from

ISSN:0108-0180    

DOI:10.1111/j.1699-0463.1984.tb02786.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

The immunoperoxidase technique in combination with electron microscopy was used for demonstration of antigenic determinants ofStaphylococcus aureuspeptidoglycan. Isolated antibodies against four synthetic peptides with amino‐acid sequences similar to those found in native staphylococcal peptidoglycans were used. A homogeneous staining of the cell wall from the outer surface to the cell membrane was demonstrate

ISSN:0108-0180    

DOI:10.1111/j.1699-0463.1984.tb02787.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Histogram analysis of inhibition zone diameters around the 30 üg cephalothin disk forE. coli, P. mirabilis, andK. pneumoniaein samples from 1975 to 1982 showed a marked reproducibility of the disk‐diffusion antibiotic‐susceptibility test in the routine laboratory. A comparison of interpretive breakpoints with histograms forE. coli, P. mirabilis, K. pneumoniae, S. aureus, coagulase‐negative staphylococci, andS. faecalisshowed a higher proportion of possible misinterpretations using the breakpoints of the Swedish Reference Group, SRG, as compared to international (NCCLS) breakpoints. Further analysis using single‐strain regression analysis revealed two major causes of interpretive errors. Firstly, the laboratory‐related regression line for a bacterial species can be different from the general regression line of the reference laboratory. This difference has to be corrected by using species‐related breakpoints. ForE. coli, a species‐specific breakpoint was determined to R =>13 mm. Secondly, MIC limits recommended for the susceptibility categories of cephalothin by SRG are lower than the international limits and close to the true MIC values of many bacterial isolates, leading to misinterpretations due to the methodological variation. These studies suggest an adoption of international MIC limits for the susceptibility categories of cephalothin in Scandinavia. The »I« category should denote an indeterminate zone. A multi‐laboratory quality control assessment using histogram analysis is recommended with optional single‐strain regression analysis to determine breakpoints for problem combinations of bacterial spe

ISSN:0108-0180    

DOI:10.1111/j.1699-0463.1984.tb02788.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Twenty M protein‐positive and eight M protein‐negative strains of group A streptococci were investigated with respect to surface hydrophobicity and amount of lipoteichoic acid (LTA). Surface hydrophobicity as determined in polymer two‐phase systems varied substantially between individual strains and there was no correlation to the presence of antiphagocytic M protein. The amount of LTA on the surface of the bacteria varied with hydrophobic affinity of the cells. Strains with a high content of surface LTA were found among both M‐positive and M‐negative streptococci. Cellular and extracellular LTA was estimated on six strains by the ability of hot phenol extracts and culture fluids to sensitize erythrocytes and by rocket immunoelectrophoretic quantitation. Differences in content of surface LTA did not correlate to differences in the total amount of cellular LTA. Pepsin digestion of M‐positive group A streptococci at suboptimal pH resulted in a loss of M antigen whereas surface LTA and the hydrophobic interaction liability was retained. The results indicate that the degree of surface hydrophobicity as measured by two‐phase partitioning is not correlated to either the type‐specific or the antiphagocytic moiety of M protein. The results support the correlation between surface LTA and surface hydrophobicity of group

ISSN:0108-0180    

DOI:10.1111/j.1699-0463.1984.tb02789.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Pseudomonas aeruginosastrains have been assayed for endopeptidase activities in cultures of recently isolated variants, as well as in cultures from two‐months‐old variants derived from the same strains. Using chromogenic peptides, information was gained on both extracellular and cell‐bound endopeptidases. Production ofextracellularendopeptidases detected in the recent isolates tended to decrease or was abolished in the two‐months‐old sub‐cultures. Their pattern of activities also showed some distinct differences between the strains. By means of caseinate precipitation, the production of extracellular endopeptidases was found to present important variations, both according to the strain, and according to the duration of the incubation time. Thecell‐boundendopeptidases were found to be relatively stable features, independent of the time passed since isolation. Their pattern of activities was also rather similar amon

ISSN:0108-0180    

DOI:10.1111/j.1699-0463.1984.tb02790.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Ninety‐seven strains of clinically isolated Corynebacterium strains, probably identical with Corynebacterium JK, are described especially in regard to growth in relation to different lipid substances. The corynebacteria formed a homogeneous group of strict aerobic slow‐growing, catalase‐positive, urease‐and‐nitrate‐negative typical coryneform rods. Acid was produced from glucose and maltose. Growth was stimulated in the presence of different lipid substances and lipodependence was suggested by satellite growth only around oleic acid drops on otherwise lipid‐depleted agar plates. Generally the isolated corynebacteria were resistant to clinically achievable concentrations of penicillins, cephalosporines and aminoglucosides but uniformly sensitive to vancomycin

ISSN:0108-0180    

DOI:10.1111/j.1699-0463.1984.tb02791.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

The influence of infection of HEp‐2 cells with Coxsackie B 1 virus on the invasiveness ofSalmonella typhimuriumhas been studied. The bacterial invasiveness was significantly increased in the cell cultures incubated with virus before bacterial inoculation. This effect was a function of time after introduction of virus into the cell cultures and the concentration of virus. The increase in bacterial invasiveness was observed before production of infectious virus particles and before development of cytopathogenic effect was evident. Two strains of non‐invasiveEscherichia colidid not show invasiveness after the virus treatment of the cells. The results indicate a specific mechanism for the interact

ISSN:0108-0180    

DOI:10.1111/j.1699-0463.1984.tb02792.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Adaptation to cholera toxin (CT) and the heat‐labile enterotoxin (LT) fromE. coliis studiedin vivoin the rat small intestine. Repeated peroral pretreatment with CT or LT induces protracted inhibition of the intestinal fluid response to these toxins. The CT‐induced mucus release from intestinal goblet cells is not influenced by CT pretreatment and the binding of CT to the epithelium remains intact. However, the adenylate cyclase activity, which mediates CT and LT action, is repressed – as judged from the response of this enzyme to both CT, LT and prostaglandin E1. The results suggests that protection against CT and LT acquired in the gut is achieved by desensitization of the adenylate cyclase s

ISSN:0108-0180    

DOI:10.1111/j.1699-0463.1984.tb02793.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Thirteen serovars ofUreaplasma urealyticumwere analyzed for the ability to cleave human IgA. Strains of all of the serovars tested cleaved IgA1 in the hinge region of the α‐chain, resulting in intact Fc and monomeric Fab fragments. IgA1 protease activity was also observed in concentrated cell‐free extracts of spent cultivation medium, indicating that the IgA1 protease was excreted into the medium during growth of the micro‐organisms. Five clinical isolates ofU. urealyticumobtained from urine, cervix, vagina, amniotic fluid, and synovial fluid were positive for IgA1 protease activity. No proteolytic activity was observed against human IgA2, IgG, or IgM. Strains ofMycoplasma fermentans, M. salivariumand seven serovars ofM. hominiswere negative for IgA1 protease ac

ISSN:0108-0180    

DOI:10.1111/j.1699-0463.1984.tb02794.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Recently, we reported that conjugal transfer of plasmid pERL1, determining i. a. erythromycin resistance (Emr), into group A streptococci could trigger the expression of anti‐phagocytic activity, adhesiveness, opacity factor and capacity to bind immunoglobulin Fc‐parts and beta2‐microglobulin. In the present study, ethidium bromide treatment of Emrtransconjugants allowed the selection of »cured«, erythromycin sensitive (Ems) mutants. This procedure did not affect the expression of the abovementioned characteristics. However, when plasmid pERL1 was again transferred to two such mutants, the »secondary«, Emrtransconjugants obtained showed lack of each of these properties. Our experiments thus demonstrated a »switch‐on« as well as a »switch‐off« effect, exerted by the same plasmid, pERL1, on some major pathogenic properties of gr

ISSN:0108-0180    

DOI:10.1111/j.1699-0463.1984.tb02795.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY