Biomedical subjects

D Danielsson

Publications and source records attributed to D Danielsson.

At least 73 records · Page 4Linked to original sources

PubMed1985

Cross-reactions between alpha-streptococci and Omniserum, a polyvalent pneumococcal serum, demonstrated by direct immunofluorescence, immunoelectroosmophoresis, and latex agglutination.

In recent years several groups have used serological methods to demonstrate pneumococcal capsular antigens in sputum. In the present study 123 strains of alpha-hemolytic streptococci (including 97 strains from sputum or pharyngeal specimens) were tested for cross-reactions with a polyvalent antipneumococcal serum (Omniserum). Representatives of the following species were included: Streptococcus bovis, S. equinus, S. intermedius, S. lactis, S. milleri, S. mitis, S. mutans, S. sobrinus, S. salivarius, S. sanguis, S. suis, and Aerococcus viridans. Serological reactions were detected by direct immunofluorescence, immunoelectroosmophoresis, and latex agglutination. Fifteen (12%) of the strains gave positive reactions by all three methods. Positive reactions were also observed with another 32 strains (26%) with two of the methods, whereas 37 strains (30%) gave positive reactions by just one technique. Altogether 84 (68%) strains gave positive reactions with one or more of the methods. Latex agglutination gave positive reactions with 26 (21%) strains compared with 57 (46%) in immunofluorescence and 63 (51%) in immunoelectroosmophoresis. Absorption of the antiserum with one alpha-hemolytic strain reduced but did not entirely eliminate the cross-reactions with five tested strains. These findings indicate a potential risk of cross-reactions with polyvalent antipneumococcal serum in tests carried out on sputa or other specimens which may be contaminated with alpha-hemolytic streptococci.

Cross Reactions↗

PubMed1985

Incidence and prevalence of primary biliary cirrhosis in a defined population in Sweden.

The incidence and prevalence of antimitochondrial antibody-positive primary biliary cirrhosis (PBC) has been studied within a defined area in Sweden served by one hospital. During the period 1976-1983 the yearly incidence of PBC was 1.4/10(5) inhabitants, and on 31 December 1983 the prevalence was 12.8/10(5) inhabitants. The prevalence is the highest reported so far. At the time of diagnosis half of the patients were clinically asymptomatic. Two of the patients also had celiac disease with osteomalacia responding to a gluten-free diet. Gallstone disease occurred in 30% of the patients. Four patients died--two of liver-related complications, one of colonic carcinoma, and one of staphylococcal septicemia and endocarditis. One further patient, who is still alive, developed hypernephroma. Our results indicate that PBC is a fairly benign disease in most patients, with a slow progress during which they lead a fairly normal life.

Adult↗

PubMed1985

Difference in prevalence of hepatitis B markers in children born either in Sweden or in Turkey of Assyrian immigrants.

Sera from 95 children below 20 years of age born to Assyrian immigrants were tested for markers for hepatitis B virus (HBV). HBV markers were found in 26% of the study population. However, no markers were demonstrated in children born in Sweden. Of the 62 children born in Turkey or the Middle East 39% had HBV markers and 4 (6.5%) had HBsAg. Three of the 4 HBsAg+ children had anti-HBe and 1 HBeAg. These results suggest that the transmission of HB in Assyrians may be mainly horizontal rather than vertical. Children of Assyrian immigrants born in Sweden do not seem to constitute a risk group for transmission of HB, whereas those born in Turkey or the Middle East constitute the same risk as reported in a general population of Turks.

Adolescent↗

PubMed1985

Genomic fingerprinting in the epidemiology of gonorrhoea.

We investigated the usefulness of the restriction enzyme (RE) fingerprinting for epidemiological tracing in gonococcal disease. The RE patterns of three paired gonococcal isolates showed corresponding identical fingerprints. Within each of the three pairs of epidemiologically linked isolates the respective restriction patterns were completely identical. Also, the restriction patterns of 6 strains from a larger contact group were identical. Identical restriction patterns were also obtained in each of the two cases where isolates were recovered from both urethra and cervix. The serological findings were in perfect agreement with the genomic fingerprinting as to the identity between all strains of the same epidemiologic chain. Relapse of the original infection could be excluded in one case by the finding of a different RE pattern and also a different serovar pattern of the strain recovered 4 months later.

DNA Restriction Enzymes↗

PubMed1984

Restriction endonuclease fingerprinting of chromosomal DNA of Neisseria gonorrhoeae.

Twenty gonococcal isolates representing different serovars of the protein IA & IB serogroups, as determined by co-agglutination with monoclonal antibodies, were investigated by the restriction enzyme (RE) technique with Hind III enzyme. The patterns resulting from RE digestion and subsequent electrophoresis of the DNA fragments in gel consisted of 40-45 bands. Eight RE patterns were observed among ten of the protein IA strains representing three serovars with an identical pattern for three strains of the same serovar with positive epidemiology. Seven RE patterns were observed among ten of the protein IB strains representing five serovars with identical patterns for each of three pairs with available positive epidemiology for two of them. Seven samples from the same bacterial clone extracted and digested separately showed identical band patterns. The genetic stability was illustrated by identical patterns through 41 passages in vitro and by the same band pattern of the various virulent and avirulent colony morphology variants of a particular gonococcal strain. The results show that RE analysis of the gonococcal DNA genome is well suited as an adjunct to phenotypic markers in epidemiological studies of gonorrhoea.

Chromosomes, Bacterial↗

PubMed1984

A serological study of anaerobic curved rods with rabbit hyperimmune antisera.

Anaerobic curved rods (ACR) isolated from vaginal discharge of women with a diagnosis of bacterial vaginosis (BV) were investigated with regard to bacteriologic and serologic characteristics. According to morphologic criteria, long curved rods (LCR) which were sensitive to metronidazole, and short curved rods (SCR) which showed resistance to metronidazole, were recognized. LCR degraded several sugars, whereas SCR degraded only a few carbohydrates. With the use of hyperimmune polyclonal rabbit anti-ACR antibodies, heat-labile and heat-stable antigens were demonstrated in whole cells of both LCR and SCR strains by co-agglutination (CoA). Heat-labile antigens which could be flagellae or other surface components seemed to be responsible for inter-group and inter-strain specificity and did not cross-react between LCR and SCR. Two types of heat-stable antigens, one resistant to 120 degrees C, and one resistant to 100 degrees C but not 120 degrees C, were demonstrated in both LCR and SCR. These heat-stable antigens showed considerable one-way and two-way cross-reactivities within the LCR group, and one-way cross-reactivities were also demonstrated between LCR and SCR strains. These cross-reactivities were also demonstrated by indirect immunofluorescence (IFL) in untreated whole cells. The results show that IFL could be used to identify untreated whole cells and CoA to identify heated bacteria.

Animals↗

PubMed1984

Studies on rabbit hyperimmune, patient and blood donor serum with regard to bactericidal activity and serum antibodies against anaerobic curved rods from patients with bacterial vaginosis.

Serum specimens from patients with bacterial vaginosis (BV) from whom anaerobic curved rods (ACR) were isolated, from healthy female and male blood donors and from rabbits immunized with ACR were tested for anti-ACR antibodies by indirect immunofluorescence and for bactericidal activity. The rabbit sera had antibody titres ranging from 1 : 160 to 1 : 2560 but no bactericidal activity could be demonstrated. Very low titres (1:10) of IgM antibodies were detected in serum from a few patients as well as from a few female and male blood donors, whereas no IgG or IgA antibody titres (less than 1:10) were demonstrated. No bactericidal activity was found in the human sera against ACR. We conclude that no systemic antibody response can be demonstrated in patients with BV from whom such organisms are isolated. Moreover, these organisms behave differently from other Gram-negative bacterial species, in that they are resistant to normal serum as well as the specific antibody-complement-mediated bactericidal activity.

Animals↗

PubMed1984

An in vitro study of the attachment to vaginal epithelial cells of anaerobic curved rods, Bacteroides bivius and Bacteroides disiens.

An in vitro test system was used to study the influence of different pH levels on the adherence of anaerobic curved rods (ACR) of the long (LCR) and short type (SCR), of Bacteroides bivius and B. disiens, to vaginal epithelial cells (VEC) obtained from healthy women. There was a significant increase in the adherence of ACR (p less than 0.05) and B. bivius (p less than 0.05) at decreasing acidity. LCR adhered significantly better than SCR at pH 7.5 as compared with pH 4.0 (p less than 0.01). 'Clue cells' seen in wet mounts from vaginal discharge of women with bacterial vaginosis were very similar to VEC covered with ACR in in vitro tests.

Bacteria, Anaerobic↗

PubMed1983

Diagnosis of urogenital gonorrhoea by detecting gonococcal antigen with a solid phase enzyme immunoassay (Gonozyme).

A solid phase enzyme immunoassay (Gonozyme) was used to demonstrate gonococcal antigen in urogenital specimens. Urethral specimens from 101 men and cervical specimens from 150 women were examined, and the diagnostic yields were compared with those obtained by culture. The Gonozyme test was positive in 25 patients, 15 men and 10 women, and negative in 226 patients. Gonococci were isolated by culture in 23 of the patients, 12 men and 11 women. The Gonozyme test gave false-negative results in two men and one woman patient. The sensitivity of the test was 87% for the men and 91% for the women. Correspondingly, the test specificity was 94.3% for the men and 100% for the women, the predictive value of positive test 80% and 100%, and that of negative test 97.7 and 99.3% respectively. The Gonozyme test does not allow antibiotic sensitivity testings but has the advantage of rapidity and is not dependent upon viable organisms. The test is an attractive alternative to culture procedures for screening women patients with symptomatic or asymptomatic gonorrhoea.

Antigens, Bacterial↗

PubMed1983

Immune response to Bacteroides fragilis in experimentally infected rabbits.

Experimental Bacteroides fragilis infections in rabbits were produced by injecting 10(9)-10(10) organisms into subcutaneously implanted steel-net tissue cages. Four B. fragilis type strains with divergent antigenic set-up were used. Viable counts in the cage contents reached a steady state at 10(7)-10(9) within 2-3 weeks. Bacteria coated with immunoglobulin were demonstrated in the pus. The antibody response in serum, followed with indirect immunofluorescence and detected within 7-10 days, was dominated by IgG; IgM antibodies were also involved but to a lesser degree. Serum antibody levels were not significantly influenced by infecting dose or strain, variations in viable counts or antibiotic therapy. Antibody response was directed against heat-stable as well as heat-labile antigens. Non-homogeneous staining, i.e. positive fluorescence of some of the cells in the preparation with the remaining cells negative, was found with heterologous and homologous cells and was found to be related to heat-labile antigen.

Animals↗

PubMed1983

Epidemiology of gonorrhoea: serogroup, antibiotic susceptibility and auxotype patterns of consecutive gonococcal isolates from ten different areas of Sweden.

Consecutively isolated gonococcal strains from 10 representative geographical areas in Sweden were serogrouped according to the previously described W antigen class. The majority of the strains were antibiotic susceptibility tested and approximately one fourth of them were auxotyped. Statistically significant differences of the serogroup patterns were demonstrated between the 2 largest towns, which represented highly urbanized areas where serogroup W II dominated, and the middle sized towns with adjoining rural districts, where serogroup W I dominated. The serogroup patterns of the strains isolated in 3 university towns were representative for Sweden as a whole. Statistically significant differences were demonstrated between urban and rural areas with regard to the susceptibility of gonococci to beta-lactam antibiotics. About 95% of serogroup W I strains were highly sensitive to ampicillin whereas about 65% and 90% of W II and W III strains, respectively, showed decreased susceptibility. The majority of the auxotyped strains belonged to 4 main types: Pro-, Pro-Arg-Ura-, AHU- and prototrophic. The majority of the AHU- strains belonged to serogroup W I and were highly susceptible to beta-lactam antibiotics and tetracycline. Many of the Pro-Arg-Ura-strains belonged to 2 particular subserogroups within serogroup W II and showed increased resistance to beta-lactam antibiotics. Serological classification of gonococci by co-agglutination is a simple and rapid technique without need of special equipment. It could serve 2 purposes: 1) as a confirmation test for gonococci cultured from clinical specimens; 2) for serogrouping of gonococcal isolates to study the epidemiology of gonorrhoea with regard to geographical areas, race, sexual preference, treatment failure and other demographic and medical factors.

Cross-Sectional Studies↗

PubMed1983

Gonococcal W serogroups in Scandinavia. A study with polyclonal and monoclonal antibodies.

A total of 849 gonococcal strains from 659 patients in Copenhagen (Denmark), Helsinki (Finland), Oslo and Trondheim (Norway) and Stockholm (Sweden) were included in the study. Using coagglutination reagents with polyclonal and monoclonal antibodies the strains were serogrouped into the previously described gonococcal serogroups W I, W II and W III. W II strains were dominating in all five towns (60.0%-70.9% of the strains), but W III strains were rarely isolated. W I strains were more frequent among women than among men. With the monoclonal reagents, W I, W II and W III strains could be further subdivided into 12, 29 and two different serovariants (serovars), respectively. One of the W I serovars was dominating (76%-94% of W I strains) in all five towns, and apart from this serovar, only three to five other W I serovars were seen in each town. Of W II strains, on the other hand, a greater variety of serovars were seen: between six in Trondheim and 17 in Oslo, and no one was dominating as among W I strains. Different W II serovar patterns were found in the different towns. Even between the two participating laboratories in each of the towns, Oslo and Helsinki, differences were noted. The epidemiological value of this is discussed. Ten of the 11 beta-lactamase-producing gonococcal strains isolated belonged to unusual serovars. None of the monoclonal coagglutination patterns corresponded to a single polyclonal pattern. There were, however, some relations between the two systems. In earlier studies it was shown that in smaller Swedish towns W I strains dominated. A hyphothesis about protective anti-Protein I antibodies is discussed to explain the differences in distribution of W I and W II strains between smaller and larger towns and between women and men.

Adolescent↗

PubMed1982

Demonstration of heat-labile antigen(s) of Bacteroides fragilis associated with non-homogeneous immunofluorescent staining.

Rabbit hyperimmune sera against nine Bacteroides fragilis strains were tested in indirect immunofluorescence against homologous and heterologous formalin and heat-treated bacterial cells. Strain-specific heat-stable and heat-labile antigens were demonstrated as well as many cross-reactive ones. Besides these findings a striking non-homogeneous fluorescence was noted, inasmuch as varying numbers of the bacterial cells were stained while others were not. Results of absorption experiments indicated that the reactive antigens were heat-labile. Non-homogeneous fluorescence was also demonstrated with sera from patients with clinically significant Bacteroides fragilis infections.

Animals↗

PubMed1982

Genetic linkage between serogroup specificity and antibiotic resistance in Neisseria gonorrhoeae.

In previous works statistically significant differences were demonstrated in antibiotic susceptibility between gonococcal strains of the recently described W serogroups, W I, W II and W III, respectively. Strains of serogroup W I were almost always sensitive to penicillin and other antibiotics while those of the W II and W III serogroups showed a higher incidence of decreased susceptibility. Transformation experiments were therefore undertaken with an antibiotic sensitive serogroup W I gonococcal strain as recipient and a multi-resistant W II strain as DNA-donor. Transformants, with increased resistance to penicillin and several other antibiotics as compared with the recipient, acquired the same serogroup specificity as the W II donor. With one of these W II transformants as donor and the sensitive W I strain as recipient all transformants acquired the same antibiotic susceptibility pattern as well as the same serogroup as the donor. SDS-PAGE, performed on sarkosyl extracted outer membrane proteins from donor, recipient and some transformants, showed an increase in the molecular weight of the Protein I of the outer membrane of the W II transformants as compared with that of the recipient strain. In rocket-line and crossed-line immunoelectrophoresis the W II transformants could not be distinguished from the W II donor strain. A genetic linkage between antibiotic multi-resistance and serogroup W II specificity was thus shown. This is in agreement with the demonstrated higher incidence of W II strains with increased antibiotic resistance as compared with that of serogroup W I strains.

Anti-Bacterial Agents↗

PubMed1982

Preliminary identification of beta-hemolytic streptococci in throat swab cultures with a commercial blood agar slide (streptocult).

A commercial blood agar slide (Streptocult, Orion Diagnostica) was used for preliminary identification of beta-hemolytic streptococci of groups A, C, and G in throat swab specimens. The sensitivity of the test was 93.6% and the specificity was 94.7%, as judged from 580 specimens. A model is suggested for routine processing of throat swab specimens, involving inoculation and reading of the slide in general practice and transport of positive or inconclusive slides to a bacteriology laboratory for isolation and serological grouping of beta-hemolytic streptococci. The model combines preliminary detection of beta-hemolytic streptococci within 24 h with the reliability of serological groupings, and should reduce the volume of specimens sent to the laboratory considerably.

Bacteriological Techniques↗

PubMed1982

Susceptibility of bacteroides species to metronidazole during treatment of patients with Crohn's disease and healthy individuals.

Patients with Crohn's disease are usually treated with metronidazole for long periods with the risk of selecting resistant bowel bacteria. This could have serious clinical and epidemiological implications, especially with regard to Bacteroides fragilis which is the most common cause of severe anaerobic infections. An investigation was therefore undertaken with the use of an agar dilution method to examine the susceptibility to metronidazole of B. fragilis and other common Bacteroides species isolated from faeces before, during and after treatment of patients with Crohn's disease amd healthy individuals. Before treatment, or during medication with sulphasalazine, 88% of the strain tested showed minimum inhibitory concentrations (MIC values) of less than or equal to 1 mg/l and none had MIC values greater than 4 mg/l. The MIC values were significantly increased during metronidazole treatment (p less than 0.02), with a maximum value of 8 mg/l. No significant changes were noted for the MIC values of strains isolated before and 1 week to 1 month after treatment (p greater than 0.1). It is concluded that it is important to examine the MIC values of bacteroides isolates from patients with long term treatment with metronidazole, especially with regard to treatment failure.

Bacteroides↗

PubMed1982

Epidemiology of sexually transmitted diseases in the Scandinavian countries.

In the Scandinavian countries, laws require reporting of the traditional venereal diseases, i.e., gonorrhea, syphilis, lymphogranuloma venereum (LGV), and ulcus molle, or chancroid. Incidence figures for these diseases, therefore, are fairly reliable. In the Scandinavian countries, LGV and chancroid are rare diseases, and the syphilis incidence has remained low. These three diseases are typically male afflictions. Gonorrhea outnumbers the other diseases mentioned and at present has a nearly 1:1 male: female ratio. In Scandinavia, as in other parts of the world after World War II, gonorrhea has shown great epidemiological fluctuations. A heavy increase in its incidence was evident in Sweden and Denmark during the 1960s. During the 1970s, however, the incidence in Sweden dropped significantly, with the 1980 figures corresponding to those seen in 1960. Sweden now has the lowest incidence of gonorrhea among the Scandinavian countries. During the past three years, the incidence of infections with penicillinase-producing gonococci (PPNG) has increased. Most of the strains isolated have originated from the Far East. As documented in several recent investigations, genital chlamydial infections are at least as common as gonorrhea in the Scandinavian countries. Acute salpingitis has been shown to be a common complication of such infections. Among the other sexually transmitted diseases (STD), Trichomonas infections are still common. The prevalence of genital warts and of Herpes Simplex Virus (type 2) infections is increasing and within the next few years these probably can be expected to become an even greater problem than are the traditional venereal diseases, because no specific treatment is yet available.

Adolescent↗

PubMed1982

Serology of Campylobacter fetus ss. jejuni. 2 Serotyping of live bacteria by slide, latex and co-agglutination tests.

Antisera against 12 campylobacter strains (8 C. fetus ss. jejuni, 2 ss fetus and 2 ss. intestinalis) were obtained from rabbits immunized with formalin treated bacteria. Cross testing of live boiled and autoclaved organisms of these strains were performed with direct slide and tube agglutinations, and with agglutinations of latex particles and protein A-containing staphylococci coated with antibodies. Confirmed by absorption experiments both heat labile and heat stable antigens were demonstrated. The highest specificity for serological differentiation was obtained with slide and latex agglutination with live bacteria, which were subsequently used for differentiation of C. fetus ss. jejuni strains. For this purpose we applied 22 C. fetus ss. jejuni antisera absorbed with boiled homologous bacteria. Clearcut homologous reactions, with few and weak crossreactions, indicated the presence of a variety of heat labile antigens, which could form a basis for serotyping. Preliminary typing of 170 clinical isolates with slide agglutination using 17 unabsorbed C. fetus ss. jejuni antisera demonstrated the applicability of this approach for epidemiological studies. We found antigenically similar strains in family outbreaks, antigenic differences in strains of different origin, new combinations of cross reactions not seen in strains used in immunization, antigenically "new" strains not reacting with these antisera, and the dominance of a few antigenic types among the isolates.

Agglutination Tests↗