Search PubMed⌕ Search

Biomedical subjects

D Danielsson

Publications and source records attributed to D Danielsson.

At least 55 records · Page 3Linked to original sources

Gonorrhoea and syphilis in Sweden--past and present.

Gonorrhoea and syphilis that belong to our oldest recognized sexually transmitted diseases (STD) are also the prototypes of curable STDs. After the discovery of the causative organisms, Neisseria gonorrhoeae in 1879 and Treponema pallidum in 1905, diagnostic tests were developed and by this, in conjunction with instituted regulations and legislation, means were created for public health authorities to collect statistical data. Sweden has fairly reliable statistics of both syphilis and gonorrhoea from 1912 and onwards, and these data show many interesting characteristics. Syphilis was prevalent in Sweden among both males and females during World War (WW) I and peaked in 1920 with an incidence rate of 150 and 75 per 100,000 population, respectively. The incidence figures fell rapidly after 1920 and reached a low of less than 30 cases per 100,000 in the mid 1920s, probably as a result of systemic treatment with Salvarsan in conjunction with vigorous contact tracing, two important measures to bring an infectious disease under epidemiological control. There was a slight increase of male syphilis in the late 1920s and early 1930s, and of both male and female cases during WW II which never reached the incidence figures of WW I. Penicillin was introduced in the mid 1940s for treatment and was proved superior to Salvarsan. The incidence figures have been very low ever since the early 1950s.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗

Rapid diagnosis of bacterial meningitis by an enzyme immunoassay of cerebrospinal fluid.

A total of 250 cerebrospinal fluid (CSF) specimens were analyzed using a rapid enzyme immunoassay (Pharmacia Meningitis EIA-Test) (EIA) for the detection of antigens of Haemophilus influenzae type b, Neisseria meningitidis (serogroups A,B,C) and Streptococcus pneumoniae (25 selected types). The test is performed in less than 1 h and read by the naked eye. EIA and coagglutination (CoA) were compared with a constructed reference that comprised samples which were either positive by culture and/or on direct microscopy (DM), or in which there were positive results with both EIA and CoA for the bacteria covered by the assays. Using this reference for CSF samples assayed in a period between two meningococcal meningitis epidemics, the sensitivity was 0.86 for EIA and 0.69 for CoA, the specificity 0.95 (EIA) and 0.97 (CoA), the predictive value for a positive result 0.81 (EIA) and 0.87 (CoA) and, the predictive value for a negative result 0.96 (EIA) and 0.93 (CoA). Antibiotics had been given to 54% of the patients before admission. All of the 56 samples that were positive in any of the tests taken during an epidemic of group A meningococcal disease were detected by EIA; CoA was negative in 45% and culture/DM was negative in 32%. Sequential dilutions of two CSF samples from which H. influenzae type b had been isolated, showed the EIA to be 16-32 times more sensitive than CoA. With both technical feasibility and good sensitivity and specificity, the EIA seems to be useful and reliable for the rapid diagnosis of bacterial meningitis, especially in situations where pretreatment with antibiotics are likely.

Antigens, Bacterial↗

Serum immunoglobulins and IgG subclasses in patients with glomerulonephritis.

The serum concentrations of IgG, IgA, IgM and of the four subclasses of IgG were determined by radial immunodiffusion in 103 patients, mean age 42 (range 16-72), with various types of glomerulonephritis. Forty-nine healthy blood donors, mean age 41 years (range 19-65), served as controls. Kidney biopsies were obtained from all the patients for examination by histopathology and by immunofluorescence. The glomerulopathies were classified according to WHO criteria. The serum immunoglobulin patterns were different for the various clinical groups of patients. Patients with Wegener's granulomatosis, rapidly progressive glomerulonephritis and SLE had a significant increase in total IgG and of IgG4 (P less than 0.05-0.001). Patients with minimal change disease had low concentrations of IgG (P less than 0.001) with a significant decrease in IgG1 and IgG2 (P less than 0.001 and 0.01, respectively). Highly significant increases in IgA were noted for patients with IgA nephritis (P less than 0.001) but high levels were also seen in patients with chronic glomerulonephritis. The findings might have diagnostic implications.

Adolescent↗

Increased adherence to vaginal epithelial cells and phagocytic killing of gonococci and urogenital meningococci associated with heat modifiable proteins.

Urogenital Neisseria meningitidis were characterized with regard to serogroup, colony morphology, the presence of heat modifiable proteins (HMP), attachment to human vaginal and buccal epithelial cells, and phagocytic killing by polymorphonuclear leukocytes. The findings were compared with those on gonococci, and with those on meningococci isolated from blood or cerebrospinal fluid, with regard to colony morphology, HMP and piliation. The opacity colony morphology characteristic could be used to predict the presence of HMP in gonococci but not in meningococci, and sodium dodecyl sulphate polyacrylamide gel electrophoresis had to be used to demonstrate this surface protein. The urogenital meningococci, serogroup Y, attached significantly more efficinetly to vaginal epithelial cells in the presence of HMP and behaved in this respect like those of gonococci. Gonococci and meningococci containing HMP were more sensitive to phagocytic killing than those without HMP. Meningococci from opaque and transparent colonies and isolated from patients with meningococcal disease had no demonstrable HMP. They showed low adherence to vaginal and buccal epithelial cells, with no difference between organisms from opaque or transparent colonies.

Bacterial Adhesion↗

Detection of antibody responses in rabbits hyperimmunized with Campylobacter pylori. Enzyme immunoassay indicates extensive antigenic similarities.

Acid glycine extracts from four Campylobacter pylori strains and one GCLO strain were used as antigens in enzyme immunoassay (EIA). Immune responses of rabbits immunized with C. pylori strains, the GCLO-strain and other campylobacter strains were studied. All 14 rabbit antisera against C. pylori reacted with all four C. pylori extracts and there were extensive cross-reactions between these extracts. Antisera against C. jejuni and C. coli strains did not react with a C. pylori extract but reached with the GCLO antigen. Acid glycine extracts proved to be very satisfactory in C. pylori serology and the use of an extract prepared from only one strain instead of a combination of strains seems justified.

Animals↗

In vitro diagnosis of atopic allergy in children. A comparison between total IgE, conventional RAST and a new multi RAST (Phadiatop).

A new multi RAST (Phadiatop) was compared with conventional RAST and total IgE determination (PRIST) for the diagnosis of IgE-mediated allergy in children. Serum specimens were tested from 100 children with a suspected IgE-mediated allergy, restricted to the eyes and/or the respiratory tract, to inhalant allergens. Compared with a RAST panel of 12 allergens representing seven groups, the new multi RAST showed a sensitivity of 95% and a specificity of 100% with a predictive value for positive test of 100% and for negative test of 91%. Corresponding figures for total IgE elevated greater than 2 SD above mean determined with PRIST were 47%, 88% 84% and 56% respectively. We conclude that multi RAST might be a good adjunct to the clinical diagnosis of IgE-mediated allergy to inhalant allergens.

Adolescent↗

A reference procedure to study chemiluminescence induced in polymorphonuclear leukocytes by Neisseria meningitidis.

Luminol-enhanced chemiluminescence (CL) was used to study the ability of various strains of Neisseria meningitidis (MC) to induce oxidative metabolism of polymorphonuclear leukocytes (PMNL); an indirect measure of phagocytic activity. To circumvent variations related to different PMNL donors, a MC serogroup X strain was used as a control for indexing the CL responses induced by other MC strains. This procedure, with pooled serum from healthy blood donors to standardize opsonising conditions, gave reproducible and comparable results, irrespective of PMNL donors. Under these conditions, there was a highly significant difference between pathogenic and non-pathogenic MC strains as regards their ability to induce CL responses (p less than 0.001). The results indicated that the differences were due partly to opsonizing antibodies, partly to other differences related to pathogenicity of tested MC strains. These differences in leukocyte/MC interaction were also confirmed by phagocytic-killing experiments. The index procedure of CL measurements may be a suitable method to study the appearance of natural immunity to MC disease, as well as the pathogenicity of particular MC strains.

Antibodies, Bacterial↗

Bacterial adherence to endothelial cells from rat heart, with special regard to alpha-hemolytic streptococci.

Endothelial cells were prepared from rat heart, and the ability of various bacterial species to adhere to these cells was investigated, with special regard to alpha-hemolytic streptococci. The endothelial cells were identified by morphology and by the presence of F VIII antigen. Seventeen bacterial strains representing various species were used in the in vitro adherence tests; 10 strains represented various strains of alpha-hemolytic streptococci, 5 of which were isolated from patients with infective endocarditis and 5 from the throats of healthy individuals; 2 were Neisseria meningitidis, 2 N. gonorrhoeae, 2 S. aureus and 1 E. coli. The highest adherence rate was found for alpha-hemolytic streptococci isolated from patients with infective endocarditis. The difference compared to carrier strains of alpha-hemolytic streptococci and to the other tested strains was statistically highly significant.

Analysis of Variance↗

Prevalence of Campylobacter pylori in an unselected Swedish population of patients referred for gastroscopy.

A survey of the prevalence of Campylobacter pylori in an unselected series of 117 patients referred for gastroscopy showed that 49.6% of the patients were infected. In 87% of infected patients both the antrum and the body of the stomach were involved. Duodenal infection occurred in only 9% of 102 studied patients. C. pylori could usually be demonstrated in mucosa showing signs of active chronic inflammation, whereas it was rarely found in histologically normal mucosa. The acridine orange staining method for demonstration of bacilli correlated well with bacteriology; identical results were obtained in 92.8% of the samples.

Adolescent↗

Heterogeneity of Campylobacter pylori as demonstrated by co-agglutination testing with rabbit antibodies.

The indirect immunofluorescence (IFL) and the co-agglutination (CoA) methods were used to study the serology of Campylobacter pylori strains isolated from patients in different countries (Sweden, Finland, Canada and Australia). Antisera were obtained from rabbits immunized with whole cell antigens. With IFL tests the highest serum titers were obtained with C. pylori strains and their homologous antisera. These tests also showed that all the tested strains contained cross-reactive antigens. With the use of the CoA technique strain or type specific heat labile and heat stable antigens were demonstrated, and a provisional "seropattern" of a particular strain could be defined with selected CoA reagents. With the use of such reagents we were able to show that a patient may be infected with multiple C. pylori strains with different sets of surface antigens. The clinical and epidemiological implications of this serological heterogeneity of C. pylori are discussed.

Agglutination Tests↗

Bactericidal activity for Neisseria meningitidis in properdin-deficient sera.

We investigated serum bactericidal reactions against Neisseria meningitidis (serogroups A, B, C, D, Y, W-135, 29E, X, and Z) in the sera of two healthy adults with properdin deficiency. Bactericidal reactions mediated via the classic complement pathway (unchelated system) were not impaired in properdin-deficient serum. The properdin-deficient sera supported alternative pathway-mediated killing (Mg++EGTA-chelated system) of some, but not all, of the strains investigated. Vaccination of the properdin-deficient individuals with serogroup A and C polysaccharide clearly increased the concentrations of antibody to meningococci. At least some of the antibodies induced by vaccination supported the bactericidal activity of properdin-deficient serum. Some antibodies to meningococci, probably of the IgM class, promoted alternative pathway-mediated bactericidal reactions in the absence of properdin. By contrast, presensitizing meningococci with IgG enhanced the alternative pathway-mediated reactions, but this was strictly a properdin-dependent effect.

Antibodies, Bacterial↗

Diagnosis of genital Chlamydia trachomatis infection in males by cell culture and antigen detection test.

Urethral Chlamydia trachomatis infection was diagnosed in 204 of 1,011 (20.2%) male patients by cell culture, in 219 (21.7%) by an antigen detection test consisting of a solid phase immunoassay, and in 247 (24.4%) patients by both methods combined. The positive results of the two methods agreed for 176 patients, and both positive and negative results of the tests agreed for 940 patients (93%). With cell culture as the reference method, the antigen detection test had a sensitivity of 86.3%, a specificity of 94.7%, a positive predictive value of 80.4% and a negative predictive value of 96.5%. It gave false negative results in 28 patients. In 43 patients the antigen detection test gave a positive result, whereas culture was negative. Thirty-nine of these males were treated with antibiotics (tetracycline or erythromycin), 19 because their consorts had a proven Chlamydia trachomatis infection, and 20 for obvious clinical and/or microscopic findings of urethritis requiring treatment. According to this analysis there were 19 probable misses by cell culture test and four true false-positives by the antigen detection test, i.e. less than 0.4% of all patients examined. Since one-third of males with a final diagnosis of Chlamydia trachomatis infection were clinically asymptomatic efforts to control genital chlamydial infections must identify this reservoir. The antigen detection test provides an alternative diagnostic method to the more laborious and time-consuming cell culture procedure.

Antigens, Bacterial↗

Recombination near the antibiotic resistance locus penB results in antigenic variation of gonococcal outer membrane protein I.

In gonococci, the nonspecific antimicrobial resistance locus penB is known to be closely linked to loci designated nmp that alter the Mr and antigenicity of the outer membrane porin protein I (P.I). We report that after selection for the linked donor penB locus, occasional recombinants expressed P.I with some epitopes from each parent. These hybrid P.I antigens were stable on subculture and were transformed at a locus closely linked to penB. The hybrid P.I antigens were detected with monoclonal antibodies in both coagglutination and Western blot assays. The alterations of P.I antigenicity may have resulted from recombination between structural genes for P.I that are closely linked to penB.

Antigens, Bacterial↗

Some phenotypic and genotypic characteristics of prevailing gonococcal strains in northern Norway.

Ninety two non-penicillinase producing Neisseria gonorrhoeae (non-PPNG) strains were investigated by the restriction enzyme technique with Hind III enzyme. Serogrouping by coenzyme. A with monoclonal antibodies and testing susceptibility to doxycycline were also performed by an agar dilution method. Fifteen different restriction enzyme patterns were shown, of which three represented 50% (46/92) of all strains. One band, representing a deoxyribonucleic acid (DNA) fragment of 1.45 kilobase pairs, was shared by all the strains investigated. Serogroup WI dominated, representing 57 isolates (62%) with four serovars, one of which was found in 82% (47/57) of the WI serogroups. Eight serovars were found among WII and WIII serogroups, but no one serovar dominated, as happened among WI serogroups. Identical serovars and restriction enzyme patterns were found in eight patients who were epidemiologically linked. All strains were highly or moderately sensitive to doxycycline, and the strains belonging to serogroup WI were more sensitive than those in the WII or WIII serogroups.

Bacteriological Techniques↗

Phenotypic and genotypic characterization of penicillinase-producing strains of Neisseria gonorrhoeae.

Thirty penicillinase-producing Neisseria gonorrhoeae (PPNG) strains, 26 representing 9 serovars of the protein IB and 4 representing 2 serovars of the protein IA serogroup, had 10 different patterns when investigated by the restriction enzyme (RE) technique with Hind III enzyme. One RE pattern dominated, representing 11 strains with 6 different serovars of both the protein IA and IB serogroup. Identical serovars and RE patterns were found among 7 patients (3, 2 and 2, respectively) with positive epidemiology. The majority of the strains (24/30) were resistant to, or showed decreased sensitivity to, doxycycline with minimum inhibitory concentrations between 1 and 8 mg/l, consistent with the Far East origin. All the 30 PPNG strains showed by agarose gel electrophoresis to harbour a 2.8 Mdalton, a 4.4 Mdalton, as well as a 24.5 Mdalton plasmid, whereas the two non-PPNG strains had only the 2.8 Mdalton plasmid.

DNA Restriction Enzymes↗