bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence Of O and K Antigens On The Surface Properties Of Escherichia Coli In Relation To Phagocytosis
Authors: Stendahl O. , Normann B. , Edebo L.
Published: August 2010

Strains of Escherichia coli with different O and K antigens were investigated with respect to physicochemical surface characteristics and liability to phagocytosis. Using two‐phase partitioning analysis for the surface characterization, three main groups of strains emerged: Group I (O1:K1, O2:K1, O3:K2ab) showing both smooth hydrophilic O antigens and negatively‐charged K antigen which rendered the strains maximally resistant to phagocytosis. Group II (O55:K59, O111:K58) showed no acidic K antigen but only smooth hydrophilic O antigen properties. However, these strains were as resistant to phagocytosis as the strains in group I. A third group (O14:K7, O24:K +) contained strains with rough, hydrophobic O antigen and negatively‐charged K antigen. When the K antigen was removed by heat treatment these strains became more sensitive to phagocytosis. Certain other strains (O28:K‐, O56:K + and O118:K‐) did not fit into the three groups. These experiments show that the physicochemical surface effects and biological significance of the K antigen must be evaluated in relation to the properties conveyed by the corresponding O antigens.
The Interaction of Penicillin and Chloramphenicol Against Meningococci In Vitro
Authors: Solberg Otto , Andersen Björg Marit
Published: August 2010

Combinations of penicillin and chloramphenicol are frequently used initially in the treatment of bacterial meningitis. The simultaneous effects against meningococci of these two drugs were examined in vitro in a chemically defined, proteinfree medium. The investigation was performed with different combinations of the antibiotics, including optimal concentrations. In most instances, penicillin and chloramphenicol seemed to have an additive, but not an iso‐additive, effect. No antagonism was found, and only one out of nine strains showed indifference.
Genetic Transformation in Streptococcus Sanguis
Authors: Gaustad P.
Published: August 2010

Forty‐one strains of Streptococcus sanguis (37 of serogroup H and four of the newly‐described serogroup W) were examined semiquantitatively for genetic transformation with streptomycin as marker. The material comprised eight reference laboratory strains and 33 recent isolates. Eighteen strains (16 of serogroup H and two of W) showed spontaneous competence in genetic transformation (without added competence factor, i.e. culture filtrate.). Individual culture filtrates from 19 spontaneously competent and ten incompetent strains were tested for competence‐inducing effect on 23 spontaneously incompetent strains. Competence was induced in 16 of the strains, and 20 of the culture filtrates were active. There was considerable variation with respect to the number of recipient strains which were induced to competence by individual filtrates. Furthermore the recipients varied as regards the number of filtrates that were able to induce that particular strain. There was some relationship, but no complete association, between competence, competence‐inducing ability and the occurrence of spreading zones around the colonies assumed to correspond generally to fimbriation. Thus, three incompetent strains had an active culture filtrate and one spontaneously competent strain had an inactive filtrate. Most, but not all, strains with spontaneous or inducible competence showed spreading, as did most of the strains from which broadly inducing filtrates could be produced.
Studies on the Interaction Between Different O‐Serotypes of Yersinia Enterocolitica and HeLa Cells
Authors: Pedersen K. B. , Winblad S. , Bitsch V.
Published: August 2010

Eighty strains of Yersinia enterocolitica were examined for their ability to invade HeLa cells. The following O‐serotypes were found to be invasive: 1, 3, 4a, 4c, 5b, 8, 9, 15a, 18, 20, 21 and 22. Biochemically, these types are either indole‐, aesculin‐, and salicin‐negative, or indole‐positive but aesculin‐ and salicin‐negative. Other serotypes of Y. enterocolitica did not invade HeLa cells. Biochemically, these non‐invasive strains are indole‐, aesculin‐ and salicin‐positive. Also the non‐sucrose‐fermenting strains of O‐serotypes 11 and 12 were non‐invasive. The interaction with HeLa cells was not restricted to viable bacteria, since also bacterial cells inactivated by formalin or ultraviolet light could gain entrance to the HeLa cells. Heating of the bacteria to 100° C for 30 min. completely inhibited their invasiveness. Monolayer cultures of porcine kidney cells were also invaded by strains which invaded HeLa cells.
Immunochemical Analysis of the Teichoic Acid from Staphylococcus Hyicus
Authors: Osland Arve , Grov Arne , Oeding Per
Published: August 2010

The wall teichoic acid of Staphylococcus hyicus has been isolated and characterized. The teichoic acid is a glycerol phosphate polymer with glycosidically linked N‐acetylglucosamine. Interaction with concanavalin A and susceptibility to α‐ but not to β‐N‐acetylglucosamindase showed that the sugar is in the α‐configuration.
Ultrastructural Studies on the Sporulation of Oocysts of Toxoplasma Gondii
Authors: Ferguson D. J. P. , Birch‐Andersen A. , Siim J. Chr. , Hutchison W. M.
Published: August 2010

The ultrastructural changes observed during sporocyst formation and the structure of the sporocyst wall was examined in oocysts which had been allowed to sporulate for between 12 and 48 hours at 27°C. As the spherical sporoblast developed into the sporocyst the cytoplasmic mass became ellipsoidal in shape although no change was noted in the organelle compliment, which consisted of two nuclei plus a number of polysaccharide granules, lipid globules, mitochondria, Golgi bodies, and some rough endoplasmic reticulum. The sporocyst wall consisted of a thin outer layer (15–20 nm) which was formed from two limiting membranes of the sporoblast and an inner layer (40–50 nm) which was comprised of four curved plates. This inner layer was formed under the outer layer and although no specific cytoplasmic organelle disappeared with its formation, some unit membranes were observed close to the plasmalemma during its formation. Each curved plate has a marginal swelling and an interposing strip of material is present between the margins of adjacent plates. The plates are joined to the interposing strip by a thin band of osmiophilic material. In oblique and tangential sections through the plates two types of cross banding were observed which differed in periodicity.
Quantification of Tetanus Antitoxin in Human Sera
Authors: Winsnes R.
Published: August 2010

An extensive sero‐epidemiological survey of immunity to tetanus is to be performed in Norway during 1978 and 1979 and thus a simple and reliable method for screening sera for content of tetanus antitoxin is needed. An improved counter‐immunoelectrophoretic method for quantification of tetanus antitoxin is described. The toxin neutralization test in mice is considered to correlate well with protection in humans. Counter‐immunoelectrophoresis has the advantage of using tetanus toxoid instead of toxin, as well as being more rapid and less expensive. Specific antibodies of the IgG, IgM, and IgA classes could be read simultaneously for many sera. This may be of importance, since it is reported in the literature that only antibody of the IgG class is capable of neutralizing tetanus toxin in mice. Counter‐immunoelectrophoresis is limited by being less sensitive than the toxin neutralization test in mice.
Gas Chromatographic Characterization of Porcine and Human Strains Belonging to The Mycobacterium Avium‐Intracellulare Complex
Authors: Larsson Lennart , Bergman Rune , Mårdh Per‐Anders
Published: August 2010

Trifluoroacetylated whole‐cell methanolysates of 23 strains designated as belonging to the Mycobacterium avium‐intraceltulare complex by biochemical, growth chromogenicity and chicken pathogenicity tests, were analysed by gas chromatography. Twenty of the strains were isolated from pigs and the remainder from human beings. Serological typing showed that 13 of the porcine strains, but none of the human strains, belonged to M. avium. The remaining strains, except one which showed autoagglutination, did not react with antisera to M. avium (serotypes 1–3), thus suggesting that they belonged to M. intracellulare. Five different, highly reproducible chromatographic patterns, the main peaks of which were considered as representing bacterial carbohydrates and fatty acids, could be distinguished by visual examination and by cluster analysis. The chromatographic results could not be correlated with those obtained from serotyping of the strains studied. Mycobacteria recovered from different organs of one and the same pig gave virtually identical chromatograms. The strains isolated from three human beings had a chromatographic pattern which was identical with one of those produced by the porcine strains. The present investigation indicates that the gas chromatographic analytic technique used differentiates bacteria within the M. avium‐intracellulare complex, without assigning the organisms to species.
An Ultrastructural Study on the Excystation of the Sporozoites of Toxoplasma Gondii
Authors: Ferguson D. J. P. , Birch‐Andersen A. , Siim J. Chr. , Hutchison W. M.
Published: August 2010

The ultrastructural changes which occur during the in vitro excystation of the sporozoites of Toxoplasma gondii were examined. The excystation was carried out at 37° C on suspensions of oocysts which had been ground and then treated with an excysting medium containing 0.25% trypsin and 0.75% sodium taurocholate in phosphate buffered saline, pH 7.3. It was found that sporocysts within intact oocysts were unaffected while sporocysts exposed to the medium ruptured. The sporocyst wall consisted of two layers and during excystation the four plates which form the inner layer started to curl inward. At the same time changes were seen at the specialized junctions between these plates. When the junctions finally break, the plates separate. The outer layer of the sporocyst wall is then ruptured at points directly above where the plates were joined. Each of the four portions of the sporocyst wall curled inward to form a tightly wound whorl. The sporozoites can escape through the openings created between the portions of the sporocyst wall.
Chemotaxis or Migration Inhibition of Rabbit Peritoneal Polymorphonuclear Leukocytes Caused by Chemoattractants at Various Concentrations
Authors: Sveen Kjell
Published: August 2010

Purified lipopolysaccharide (LPS) from Veillonella incubated in normal rabbit serum was tested for chemotactic activity on rabbit polymorphonuclear leukocytes (PMNs) in modified Boyden chambers. In doses above those giving optimal response (over‐optimal dose), a decrease of the PMN migration activity was found. This decrease also correlated well with an increase in the migration inhibition of the PMNs as demonstrated with the capillary tube assay. The PMN chemotactic factor isolated from LPS‐induced inflammatory exudate (LPS‐CF) in rabbits, produced both a decrease in chemotactic response and a migration inhibition of PMNs in over‐optimal doses. This inhibitory effect was not due to cytotoxicity, proved by the trypan blue exclusion test. Also, a reduced locomotion of PMNs first preincubated with chemoattractants and then reactivated, was shown when the same PMNs were restimulated to migration using the same chemoattractants. This was interpreted as a deactivation of the cells. A cross‐deactivation was demonstrated between LPS‐CF and casein. The results from the experiments reported show that the Boyden chamber may be used to discriminate directional chemotaxis and migration inhibition. It may also be concluded from the study that the reduced migration activity of PMNs at over‐optimal doses of chemoattractants is not due to cytotoxicity, but most probably is caused by a deactivation of the cells.
Antibodies to the Strain‐Specific and Cross‐Reactive Determinants of the Haemagglutinin of Influenza H3N2 Viruses
Authors: Haaheim Lars R. , Schild Geoffrey C.
Published: August 2010

The serological analysis of antibodies to the haemagglutinin (HA) of influenza A viruses of the Hong Kong (H3N2) subtype is described, using haemagglutination‐inhibition, immuno‐double‐diffusion and single‐radial‐diffusion techniques. By cross‐absorption of antisera to purified HA antigens, different populations of antibody molecules were obtained, which are designated strain‐specific and cross‐reactive and characterized in terms of their antigenic specificities for HA antigens of the homologous and antigenically variant H3N2 viruses. A narrowly strain‐specific population of antibodies (SS“HK) was obtained as the residual antibody in antiserum to A/Hong Kong/1/68 HA after absorption with the closely related A/England/42/72 virus, whilst a contrasting broadly cross‐reactive population (CR‘HK) was obtained by absorption of the anti‐A/Hong Kong/1/68 HA serum with the more distantly related strain A/Victoria/3/75 and eluting the cross‐reactive antibodies from the absorbing virus. Similarly, specific and cross‐reactive antibodies were derived from antiserum to A/Victoria/3/75 HA antigen by absorption with A/Hong Kong/1/68 virus. Single‐radial‐diffusion tests were performed, involving sequential application of different antibody preparations in the same wells in immunoplates containing intact virus particles. The cross‐reactive and strain‐specific antibodies differed in their property of mutual interference of attachment to antigen. The results suggested that the cross‐reactive antigenic determinants on the HA subunit may be located closer to the distal end of the molecule than the strain‐specific determinants. Further tests employing single‐radial‐diffusion showed that there are more cross‐reactive than strain‐specific sites available for antibody in the intact virus particle. The strain‐specific antibodies also gave higher haemagglutination‐inhibition titres per ***μg IgG than the cross‐reactive antibodies.
Group L Streptococci As the Cause of Bacteraemia and Endocarditis
Authors: Bevanger Lars , Stamnes Tor Ivar
Published: August 2010

A beta‐haemolytic streptococcus was isolated from multiple blood cultures in a 56‐year‐old woman suffering from thrombophlebitis in a leg and from a 42‐year‐old man with endocarditis. Both strains were identified as group L streptococci by precipitation testing. Initially they were identified as group A streptococci on the basis of cultural characteristics, bacitracin sensitivity and fluorescent staining with an anti‐group A conjugate. The two cases are an addition to the few existing reports on proved infection in humans by group L streptococci.
Cross‐Reactions Between Staphylococcus Aureus and Fifteen Other Bacterial Species
Authors: SchiØtz P. O. , HØiby N. , Hertz J. B.
Published: August 2010

Fifty‐five different antigens were demonstrated in an antigen preparation obtained by sonication of a protein A ‐free strain of Staphylococcus aureus, using crossed immunoelectrophoresis and antiserum obtained from rabbits. The antigens were characterized by absorption experiments with formalin‐killed bacterial cells, temperature resistance and protein and polysaccharide staining. One of the antigens showed reaction of identity with a preparation of teichoic acid from S. aureus. Using this reference system, cross‐reactions between the S. aureus reference strain and S. aureus strains from the four phage groups as well as 15 other bacterial species, were studied by various quantitative immunoelectrophoretic methods. The S. aureus antigens from the four phage groups showed almost 100% cross‐reactivity for all antigens, while antigens from nine other bacterial species cross‐reacted to varying degrees with one to four S. aureus antigens. All of 12 S. aureus antigens cross‐reacted with the four S. epidermidis biotypes.
Precipitating Antibodies Against Haemophilus Influenzae and Staphylococcus Aureus in Sputum and Serum From Patients With Cystic Fibrosis
Authors: SchiØtz P. O. , HØiby N.
Published: August 2010

Serum and sputum sol phase from 23 patients with cystic fibrosis (CF) were examined for occurrence and titres of precipitins against Haemophilus influenzae and Staphylococcus aureus by means of crossed immunoelectrophoresis with intermediate gel. The patients had from four to nine H. influenzae precipitins in serum and in most cases fewer precipitins in sputum, but, on an average, there was no difference between the titres of the antibodies in serum and sputum. Most of the antibodies were crossreactive with other species, notably those of the Haemophilus genus. S. aureus precipitins were generally found in higher numbers in serum than in sputum, but, on an average, the titre of the precipitins in spulum was higher than in serum. Three of the precipitins were detectable only in sputum and not in serum, and one of these is a S. aureus‐specific precipitin. Most of the antibodies were cross‐reactive with other species, and these antibodies were often present in sputum in much higher titres than in the corresponding sera. Antibodies against teichoic acid of the S. aureus cell wall could not be demonstrated in sputum, while they were presenl in 22 sera. The possible role of the local pulmonary humoral immune response in protective immunity and in the pathology of the lung disease in CF is discussed.
Occurrence and Characterization of »Avium‐Like« Mycobacteria Isolated from Animals in Sweden
Authors: Bergman Rune , Holmberg Olof
Published: August 2010

431 cultures of »avium‐like« mycobacteria (ALM) were isolated from wild and domestic animals during 1974–76 at the National Veterinary Institute, Stockholm. Of these. 50 isolates from pigs were studied by growth‐chromogenicity, pathogenicity. and biochemical tests. Furthermore, thin‐layer chromathography was performed, and on some isolates serotyping. All 50 isolates belonged to Runyon's group III and were pathogenic for chicken; none was capable of splitting oleic acid from Tween 80; 47 gave tellurite reduction within a period of three days; one was arylsulphatase‐positive after three days and a further four after 14 days. The biological and biochemical tests permit assignation of the 50 isolates to the M. avium‐intracellulare complex. The lipid patterns of the isolates examined were analysed by thin‐layer chromatography. Thirty‐five of the isolates showed a lipid pattern similar to that of A 2 of the fowl reference strain; three belonged to lipid type A I and four to A 3. Eight could not be typed. Of 22 isolates, 14 could be assigned to M. avium serotypes.
Multiple Sclerosis and Common Viral Infections In Iceland
Authors: Gudmundsdóttir Sigrýdur
Published: August 2010

Sero‐epidemiological studies on a few common virus infections, including measles, rubella, mumps and varicella‐zoster, were carried out on patients with multiple sclerosis (MS) and controls matched for age, sex, and residences since birth. The frequency of antibodies against measles was signigicantly higher in the MS patients. Where measles preceded the onset of MS, the time interval varied from 3 to 32 years. In two cases, known MS patients contracted measles 9 and 3 years after their onset of MS. Furthermore, three MS patients were vaccinated against measles as adults. Two of these took part in a WHO measles vaccine trial in 1962, 18 and 6 years after the onset of MS. Both of them were seronegative prior to vaccination.
A Rubella Haemagglutination Inhibition Test Not Requiring Removal Of Non‐Specific Inhibitors
Authors: Haukenes Gunnar
Published: August 2010

The rubella haemagglutination inhibition (HI) test can be simplified and the problem of non‐specific inhibitors circumvented by allowing the haemagglutinin to react with erythrocytes before addition of the serum specimen. The elaboration of the test procedure is described, and preliminary studies indicate that the new method may prove useful both in the diagnosis of rubella infection and for determination of immunity status.
Comparison Of Two Selective Media In The Cultural Diagnosis Of Gonorrhoea
Authors: Svarva Per Leiv , Mćland Johan A.
Published: August 2010

A »chocolate« agar medium (CA‐NCV) containing nystatin, colistin and vancomycin. was compared with the MNYC medium which contain lincomycin, colistin. amphotericin and trimethoprim. A total of 277 clinical specimens were cultured for gonococci, and 120 of these showed positive cultures on either or both of the media. The MNYC medium detected 96.6 per cent of the total number of positive cultures and 92.5 per cent of the patients and the CA‐NCV medium 80 and 79 per cent, respectively. Nearly half the positive cultures were detected on the MNYC medium after 24 hours of incubation. It is concluded that the MNYC medium is superior to the CA‐NCV medium in the diagnosis of gonorrhoea.
ENZYME LINKED IMMUNOSORBENT ASSAY (ELISA) FOR DETERMINATION OF IgG ANTIBODIES TO HUMAN CYTOMEGALOVIRUS
Authors: Sarov Israel , Andersen Paul , Andersen Hans Kerzel
Published: August 2010

A solid‐phase enzyme linked immunosorbent assay (ELISA) for determination of IgG antibodies to cytomegalovirus (CMV) is described. The assay uses purified CMV and extracts of CMV infected cells as antigen. Antigens were desiccated onto the bottom surface of polystyrene microcuvettes. The antibodies bound to the antigens were assayed by anti‐IgG‐alkaline phosphate conjugate followed by addition of the enzyme substrate. Titration curves have been obtained from the sera of 35 blood donors and of 23 patients. Comparison of results obtained by ELISA with those obtained by complement fixation (CF) shows that there is agreement between the tests. Both purified CMV and extracts of CMV infected cells were found to be suitable antigens. Purified CMV was of value particularly in those sera which show high reactivity against control antigen. The ELISA technique described is approximately 412 to 548 times more sensitive than the CF test when purified CMV or extracts of CMV infected cells, respectively, are used as antigens. No significant heterotypic rise to CMV was observed by ELISA in three sets of sera with seroconversion to herpes simplex virus. The ELISA technique gives objective results, is easily performed, and may be adaptable as a routine test both for serological diagnosis of CMV infection and for screening of the general population.
AN EFFECTIVE, SELECTIVE MEDIUM FOR YERSINIA ENTEROCOLITICA CONTAINING SODIUM OXALATE
Authors: Soltész Lészló V. , Schalén Claës , Märdh Per‐Anders
Published: August 2010

A medium (»Y« medium) is described, which was more efficient for the isolation of Yersinia enterocolitica from experimentally infected faecal specimens than desoxycholate‐citrate, McConkey, lactose‐sucrose‐urea (LSU) agar, and Yersinia selective medium (Wauter's medium). The »Y« medium consists of casein hydrolysate and peptone serving as carbon and energy sources. A high selectivity is achieved by its contents of sodium oxalate and bile salts. The oxalate suppresses growth of gramnegative rods, including members of the family Enterobacteriaceae and of Pseudomonas spp., while the bile salts inhibit growth of gram‐positive bacteria. In the few instances coliform rods grew on the »Y« medium, they could easily be distinguished by their fermentation of lactose, included in the medium, and the fact that colonies of organisms were surrounded by an opaque zone of precipitated bile salts. The most optimal condition for the isolation of Y. enterocolitica from stools was achieved at incubation of the »Y« medium at 29 °C for 2 days.
EPIDEMIOLOGY OF PSEUDOMONAS AERUGINOSA INFECTION IN PATIENTS TREATED AT A CYSTIC FIBROSIS CENTRE
Authors: HøIby Niels , Rosendal Kirsten
Published: August 2010

484 isolates of P. aeruginosa were obtained from the respiratory tract of 45 out of 70 cystic fibrosis (CF) patients at monthly examinations during one year at the Danish CF Centre. All isolates were sero‐grouped (O‐antigens) and phage typed, and in this way 99 per cent of the isolates could be grouped and/or typed. The isolates from CF patients belonged to many different sero‐groups, but 55 per cent were polyagglutinable, and most of these belonged to the 0–3/9 complex. This was significantly different from the distribution into O‐groups of isolates obtained from non‐CF patients. The results of the combined phage typing and sero‐grouping of the isolates revealed the occurrence of 13 clusters of distinct epidemiological types of P. aeruginosa among small groups (2–10 individuals) of CF patients. The predominating endemic strain, which was isolated from 10 (22 per cent) of the patients, belonged to the 0–3/9 complex and was lysed by phage 109, either alone or in combination with a few other phages. Furthermore, in a few cases the eradication of another strain of P. aeruginosa by chemotherapy was followed by colonization of the lungs with the above‐mentioned predominating strain, and this strain was associated with high lethality. According to these results, measures should be undertaken to identify and eliminate routes of cross‐infection in CF centres in order to diminish the prevalence of P. aeruginosa infection and thereby reduce the lethality of CF patients.
OCCURRENCE OF OCHRATOXIN‐ AND CITRININ‐PRODUCING FUNGI ON DEVELOPING DANISH BARLEY GRAIN
Authors: Lillehoj E. B. , Goransson B.
Published: August 2010

The distribution of Aspergillus and Penicillium spp. isolates that produce ochratoxin A (OA) and citrinin was studied on developing barley from diverse locations in Denmark during the 1977 crop year. From 33 test fields, 243 isolates of the two genera were obtained with significant numbers of isolates on the grain at the earliest sampling date (1–2 weeks postanthesis). No specific agronomic factor was linked to the distribution of Aspergillus and Penicillium spp. A taxonomic study of 108 representative isolates of the two genera showed that A. flavus, P. chrysogenum, and P. purpurrescens were the predominant species. An investigation of the toxin‐production capability of the identified species showed that seven strains (6.5%) produced OA and a single isolate synthesized citrinin. P. purpurrescens was the dominant OA‐producing species with four toxin‐positive isolates.
INHIBITION OF HEPATITIS B DANE PARTICLE DNA POLYMERASE ACTIVITY BY PYROPHOSPHATE ANALOGS
Authors: Nordenfelt E. , ÖBerg B. , Helgstrand E. , Miller E.
Published: August 2010

A DNA polymerase is associated with the core of the so‐called Dane particles. The probability that this is the hepatitis B viral DNA polymerase offers the possibility of preventing hepatitis B multiplication by selective inhibition of this enzyme. We have previously reported that trisodium phosphonoformate (PFA) inhibits Dane particle DNA polymerase. Fifteen compounds with structural similarity to PFA and pyrophosphate have now been tested for inhibition of hepatitis B virus DNA polymerase in an attempt to define the structural requirement for the inhibition. Active structures have two acid groups at close proximity of which at least one is a phosphono group. Phosphonoformate and hypophosphare were the two most active inhibitors. The Ki value for PFA was 7.2 μM when dTTP was used as variable substrate, and the mechanism of inhibition was non‐competitive. Phosphonoformate caused a rapid shut‐off of the polymerase reaction, indicating that it might inhibit elongation. The efficient inhibition of hepatitis B virus DNA polymerase by PFA and its low toxicity suggest that it could be used to inhibit hepatitis B virus multiplication in vivo.
THE OCCURRENCE OF THE TREHALOSE FERMENTING, TETRACYCLINE AND POLYMYXIN RESISTANT PHENOTYPE AMONG THE ENTEROBACTERIACEÆ
Authors: Siboni K.
Published: August 2010

In Proteus morganii, P. mirabitis, and Providencia stuartii the ability to ferment trehalose and resistance to tetracycline were associated in 90%–97% of the strains. The same was true of at least 78% of the strains of Serratia marcescens. Proteus vulgaris showed a more quantitative association of the two traits. As the characters occur independently in 3–10% of the strains, the association is considered to be due to simultaneous selection in some natural niche. The trehalose fermenting, tetracycline and polymyxin resistant species ferment few other carbohydrates, fewer than the remainder of the Serratia species.
CHANGES IN VIRULENCE, M PROTEIN AND IgG Fc RECEPTOR ACTIVITY IN A TYPE 12 GROUP A STREPTOCOCCAL STRAIN DURING MOUSE PASSAGES
Authors: Burova Larissa A. , Christensen Poul , Grubb R. , Jonsson Anders , Samuelsson Gunilla , SchaléN Claës , Svensson Maj‐Lis
Published: August 2010

A type 12 group A strain (1800) was passaged serially through mice 25 times. The ability to survive in normal human blood dropped from a growth index of 52 after the first passage to 1 after four passages. After 14 passages the growth index increased again and stabilized above 30. The virulence for mice increased from a LD100 of 108 colony forming units (CFU) to 10–100 CFU after 7 passages and then remained constant. The M12 antigen disappeared after 4 passages as tested by immunodiffusion, electroimmunoassay and indirect bactericidal tests. Three antisera, raised in rabbits against strains originally belonging to types M3, M12 and M46 but devoid of type antigens after mouse passages showed high bactericidal indices against the 1800 strain after 14 or more passages on mice. Anti‐type M1 serum was also found bactericidal for the passaged strains. The IgG Fc‐receptor activity of the strain isolated after each mouse passage was tested in hemagglutination experiments with human red blood cells coated with incomplete anti‐Rh and hot hydrochloric acid extracts of the strains. The capacity to agglutinate Ripley‐coated cells increased gradually during the first 12 passages and subsequently the titres of the extracts stabilized between 1:160 and 1:320. The HUN coat, useful for detection of the G3m (5) marker gave titres increasing with the number of passages while the titres for IgGl coats kept at 1:4 or below. On background of these results, the possible role of the IgG Fc‐receptor as a virulence factor is discussed.
ANTIVIRAL AND CELL MULTIPLICATION INHIBITORY ACTIVITIES OF MOUSE INTERFERON PREPARATIONS TESTED ON AN INTERFERON SENSITIVE MURINE SARCOMA CELL LINE
Authors: Degré Miklos
Published: August 2010

The cell multiplication inhibitory effect of SDS‐treated mouse interferon separated into antiviral (AV) and cell multiplication inhibitory (CMI) fractions was compared to that of untreated similar interferon on a line of murine osteosarcoma cells. The untreated interferon preparation and the CMI fractions dose‐dependently inhibited the multiplication of the cells as measured by cell count and incorporation of 3H‐thymidine into the cultures. The AV fractions, containing comparable antiviral activites as the untreated interferon preparations, had only a minor effect on cell multiplication. The biochemical properties of the fractions studied remain unknown.
THE ENDOTOXIN‐LIBERATING EFFECT OF ANTIBIOTICS ON MENINGOCOCCI IN VITRO
Authors: Andersen BjøRg Marit , Solberg Otto
Published: August 2010

Three strains of Neisseria meningitidis (two endotoxin‐liberating and one in vitro variant non‐liberating) were studied during treatment with MIC and 100 times MIC values of benzylpenicillin and chloramphenicol in a chemically‐defined, protein‐free medium. Treatment with the highest dose of benzylpenicillin had the most rapid effect on meningococci, although the antibacterial effect was the same for the two penicillin concentrations after 20 h. Chloramphenicol treatment showed a much slower antibacterial effect. After 2 h of antibacterial treatment, an increase of filtrable endotoxin in the medium was found for the endotoxin‐liberating strains only when the highest penicillin dose was used. During the same period there was a rapid cell death. After 20 hours of treatment, however, the endotoxin‐liberating strains treated with high and low concentrations of penicillin had a markedly reduced content of filtrable endotoxin, compared to the controls and to the cultures treated with chloramphenicol. Antibacterial treatment had no, or only minimal, effect on the total content of endotoxin in the cultures, compared to the untreated controls. The endotoxin non‐liberating strain had about the same total content of endotoxin as the liberating strains, but did not liberate filtrable endotoxin into the medium unless filtered with a much higher pressure through a filter with smaller pore size.
QUANTITATIVE IMMUNOELECTROPHORETIC ANALYSIS OF SALMONELLA TYPHI ANTIGENS AND OF CORRESPONDING ANTIBODIES IN HUMAN SERA
Authors: Espersen F. , Hertz J. B. , HøIby N. , Mogensen H. H.
Published: August 2010

By quantitative immunoelectrophoretic methods, 86 different antigens were found in sonicated preparations of a Salmonella typhi, using corresponding rabbit antiserum. Lipopolysaccharide was identified, and 5 other antigens characterized. Antibodies against a total of 19 S. typhi antigens were found in human sera. The antibody response in patients with typhoid fever was significantly more pronounced compared to that in normal persons. When the antibody response was expressed as a precipitin score, the predictive value of both a positive (precipitin score 8) test and a negative test was 100%, when sera from patients suffering from typhoid fever were compared with sera from normal persons.
STUDIES ON THE PATHOGENICITY OF YERSINIA ENTEROCOLITICA AND Y. ENTEROCOLITICA‐LIKE BACTERIA.
Authors: Kapperud Georg
Published: August 2010

Altogether, 412 strains of Yersinia enterocolitica and Y. enterocolitica‐like bacteria from environmental and human sources were examined for their ability to produce enterotoxin at 22°C and 37°C using the infant mouse assay. A total of 73 strains were positive at 22°C, only. Another 28 strains were positive both at 22°C and 37°C. Of these 28 strains, 26 were sucrose and aesculin non‐fermenting and all were Voges‐Proskauer negative. All of these strains were isolated from non‐human sources. All of 13 strains belonging to O‐serogroup 28 produced enterotoxin at 37°C. The results indicate that enterotoxin production at 22°C is widespread in Y. enterocolitica with the highest prevalence among human clinical isolates. Enterotoxin production at both 22°C and 37°C seems to be common in Y. kristensenii (sucrose non‐fermentors). Enterotoxin production is apparently rare in Y. frederiksenii (rhamnose fermentors) and in Y. intermedia (rhamnose and melibiose fermentors).
QUANTITATION OF M ANTIGEN IN LANCEFIELD EXTRACTS OF GROUP A STREPTOCOCCI TYPE 12 USING ELECTRO‐IMMUNO ASSAY.
Authors: Eliasson Ingvar , Svensson Maj‐Lis , Ramstorp GöRan , SchaléN ClaéS , Christensen Poul
Published: August 2010

Anti‐type 12 serum incorporated in agarose‐polyethylene glycol gel in a concentration of 1.5% (vol/vol) was found to enable a distinct rocket precipitate in electro‐immuno assay using hot hydrochloric acid extract of type 12 group A streptococci. This precipitate was removed by trypsin treatment of the extract and on addition of anti‐M12 typing serum but not of five other typing sera to the extract. The streptococcal component responsible for this precipitate was eluted from a CM‐cellulose ion exchange column at pH 6.5. These findings demonstrated that the precipitate was caused by the M12 antigen. Crossed immuno‐electrophoresis of hot hydrochloric acid extracts of three different type 12 group A streptococci showed that the electrophoretic mobility of the M12 antigens was similar in the three extracts. A linear correlation was obtained between the concentration of the M12‐antigen and the height of the precipitate obtained in the electro‐immuno assay using different dilutions of a standard type 12 extract. M12 antigen could thus be quantitated by the electro‐immuno assay. In quantitation experiments, uniformly prepared extracts of five randomlyselected, freshly‐isolated type 12 strains were found to contain from 130 to 1850% of M12 antigen, respectively (expressed in % of the content of the standard type 12 extract).
YERSINIA ENTEROCOLITICA AND Y. ENTEROCOLITICA‐LIKE BACTERIA ISOLATED FROM HEALTHY HUMANS IN NORWAY
Authors: Kapperud Georg
Published: August 2010

Faeces samples from a total of 397 presumably healthy students in Norway were collected during April to September, 1979. Twenty strains of Y. enterocolitica and Y. enterocolitica‐like bacteria were isolated from 10 (3%) of these students. Six students harboured 2–4 antigenically distinct strains. Of the total of 20 strains, 14 were typical Y. enterocolitica isolates, representing five different serogroups (4, 5, 6, 7–8, 13–7 and non‐agglutinable). The remaining six strains were tentatively designated Y. enterocolitica‐like bacteria. They showed atypical reactions with respect to one or more of the following characters: fermentation of rhamnose, sucrose, cellobiose and sorbose. The strains recovered from healthy humans in this work were similar to strains previously isolated from wild‐living mammals, fish and water in Scandinavia. Nine strains produced enterotoxin at 22°C but not at 37°C.
AN IN VITRO EVALUATION OF TWO COMMERCIAL BLOOD CULTURE MEDIA – SUPPLEMENTED PEPTONE BROTH AND SUPPLEMENTED TRYPTONE SOYA BROTH
Authors: Sandven Per , HøIby E. Arne
Published: August 2010

Two commercial blood culture media – supplemented peptone broth and supplemented tryptone soya broth – were compared by an in vitro method. The two media were inoculated with microorganisms suspended in fresh human blood in an attempt to mimic the clinical situation. The two media differed completely in their ability to support the growth of Neisseria meningitidis and Neisseria gonorrhoeae. Macroscopic evaluation of the blood culture medium during the incubation period was difficult when using supplemented tryptone soya broth in contrast to supplemented peptone broth. The former medium remained turbid whether microorganisms were growing or not. No other important differences between the two media were detected. Our findings indicate a need for both in vitro and in vivo studies to evaluate blood culture media and also a need for quality control of microbiological diagnostic devices before they are released for clinical use.
RESISTANCE TYPES IN ESCHERICHIA COLI. II. Transfer of Ampicillin Resistance
Authors: SøGaard Per
Published: August 2010

The ability to transfer resistance traits was investigated in 49 E. coli strains isolated from clinical specimens. The strains were divided into three groups according to sensitivity to penicillin derivatives. Group 1 contained 8 ampicillin‐carbenicillin sensitive (A‐s/Ca‐s) strains, group 2 contained 16 ampicillin resistent‐carbenicillin sensitive (A‐r/Ca‐s) strains and group 3 contained 25 ampicillin‐carbenicillin resistant strains. In group 3, 17 strains could transfer A‐resistance (range of transfer frequency was 100.0 to 10‐7.5). The 16 strains in group 2 did not transfer A‐resistance more often than mutants arose from the recipient (10‐8.8). The mutants of the recipient selected on A‐plates were A‐r/Ca‐s/cephalothin‐resistant, exactly as the strains in group 2. The A‐resistance in group 3 was probably based on plasmids, and that of group 2 was based on mobilizable plasmids and/or chromosomal resistance. The frequencies of transfer of sulphonamide‐, tetracycline‐ and streptomycin resistance of the strains in groups 1 and 2 that did transfer, were in the same range as the frequencies of transfer in group 3.
PURIFICATION AND CHARACTERIZATION OF ALEUTIAN DISEASE VIRUS
Authors: Aasted Bent
Published: August 2010

Virus was isolated from infected mink organs by a combination of tissue homogenization, fluorocarbon extraction and ultracentrifugation. The final preparation was analysed by crossed immunoelectrophoresis and electronmicroscopy. Virions had a capsid diameter of 22 nm. Preparative agarose electrophoresis separated virions from contaminating ferritin. Crossed immunoelectrophoresis of virus gave a single precipitate with sera from infected mink. Crossed immunoelectrophoretic analysis with intermediate gels showed that a part of the virus preparation was complexed with antibody. Serum from a certain mink was found to contain precipitating antibody to (poly)nucleotid. Virus and virus‐antibody complexes were found to focus at pH 4.0–4.4 in isoelectric focusing. In SDS‐polyacrylamide gel‐electrophoresis the main virus protein was found to have a molecular weight of 69000. This study gives further support to the classification of aleutian disease virus as a parvovirus.
ANTIBODIES TO THE STRAIN‐SPECIFIC AND CROSS‐REACTIVE DETERMINANTS OF THE HAEMAGGLUTININ OF INFLUENZA H3N2 VIRUSES.
Authors: Haaheim L. R. , Schild G. C.
Published: August 2010

Antibodies to the strain‐specific (SS) and cross‐reactive (CR) antigenic determinants of the haemagglutinin (HA) of influenza H3N2 viruses were prepared, and their antiviral properties in experimentally infected mice and in eggs were investigated. The SS antibodies were considerably more efficient than the CR antibodies in direct virus neutralization tests. The difference in the activities of the two types of antibody preparations was less pronounced in virus growth inhibition studies in the allantois‐on‐shell system and in passive protection studies in mice given antibody before challenge with virus. Nevertheless, even in these tests SS antibody was approximately four‐fold more effective than was CR antibody in protection against fatal infection. Passive administration of CR or SS antibody preparations to mice challenged with sublethal virus doses, reduced the peak pulmonary titres of virus on day three post‐infection compared with the control animals. The degree of reduction in titre exerted by the SS antibodies was greater than for the CR antibodies. In contrast, the rate of clearance of pulmonary virus 9–12 days after infection in the mice treated with SS antibody was slower than for the CR treated animals. Also, in SS antibody treated animals viruses isolated from mouse lungs showed evidence of minor antigenic variation away from the parent virus.
ANTIBODIES TO THE STRAIN‐SPECIFIC AND CROSS‐REACTIVE DETERMINANTS OF THE HAEMAGGLUTININ OF INFLUENZA H3N2 VIRUSES.
Authors: Haaheim Lars R.
Published: August 2010

Antigenic variants of influenza A/Hong Kong/1/68 (H3N2) were obtained in vitro by letting virus multiply in the allantois‐on‐shell system in the presence of anti‐haemagglutinin antibodies, prepared from immune goat serum to purified haemagglutinin antigen, and in vivo by giving mice antibody intraperitoneally one day before challenge with a sublethal dose of live virus. In both systems it was shown that the most narrowly reacting strain‐specific antibodies selected antigenic variants at an apparently higher rate than a more cross‐reactive preparation of antibodies.
DEOXYRIBONUCLEIC ACID IS A SIGNIFICANT COMPONENT OF THE SMALL‐INTESTINAL MUCUS
Authors: Ferencz A. , øRskov I. , øRskov F. , Klemm P.
Published: August 2010

During investigations into the role of intestinal mucus for the attachment of Enterobacteriaceae to the intestinal surface it was surprisingly found that DNA was a significant component of the mucus from the rabbit small intestine.
COMPARISON OF THE SENSITIVITY OF ELISA AND THE HAEMAGGLUTINATION‐INHIBITION TEST FOR ROUTINE DIAGNOSIS OF RUBELLA
Authors: Vejtorp M. , Leerhoy J.
Published: August 2010

A total of 500 paired sera were tested for rubella antibodies by the rubella IgG ELISA and the haemagglutination‐inhibition (HI) test. Significant differences between the antibody level in the first and second samples of 417 serum pairs were not detected by either of the tests, whereas significant increases in 71 pairs were detected by both methods. A significant increase of the level in 12 serum pairs was demonstrated by the ELISA, but not by the HI test. The rubella IgG ELISA is more sensitive than the HI test for diagnosis of recent rubella.
ANALYSIS OF BACTERIAL CELL WALL PROTEINS AND HUMAN SERUM PROTEINS BOUND TO BACTERIAL CELL SURFACES
Authors: BJÖRCK LARS , KRONVALL GÖRAN
Published: August 2010

A method was developed for the characterization of proteins non‐covalently bound to the cell wall of Gram‐positive cocci. The method employs radioactive labelling of cell wall proteins followed by solubilisation and analysis on polyacrylamide gel electrophoresis in sodium dodecyl sulphate. Using this experimental procedure, protein patterns obtained from group A. C and G streptococcal strains showed marked similarities within each group. Protein peaks were also found to be shared between group C and G strains. Two major peaks with molecular weights of about 30000 and 70000 characterized group A strains, whereas group C and G strains showed one consistent peak of about 45000, thus reflecting the closer relationship between these two groups as compared to group A streptococci. By incubating bacteria with human serum proteins before labelling, solubilisation and electrophoretic analysis, it was also possible to study external proteins specifically bound to the bacterial surface. A group G streptococcus, strain G 148, showed protein peaks corresponding to its known specific binding of human albumin and immunoglobulin G, but also additional protein peaks. When Staphylociccus aureus, strain Cowan I, was pre‐incubated with human serum in excess, protein peaks corresponding to heavy and light chains of immunoglobulins were seen. Three more protein peaks of serum origin were also detected, indicating binding of proteins other than Ig to S. aureus. Experiments with protein A‐coated Sepharose beads resulted in the same protein pattern, suggesting that binding of these different polypeptides is indeed mediated by protein A.
A STUDY OF THE ELIMINATION PHASE OF PHAGOCYTOSIS OF 32P‐LABELLED ESCHERICHIA COLI BY HUMAN POLYMORPHONUCLEAR CELLS
Authors: Metby Kjetil , Midtvedt Tore
Published: August 2010

A study of the elimination phase of phagocytosis of a radio‐labelled strain of Escherichia coli by human polymorphonuclear cells is presented. In the presence of normal serum during the ingestion and post‐ingestion phases, the elimination was 55%. Omission of normal serum during the post‐ingesiive phase resulted in an elimination of 35%. Without serum in both phases the elimination was approximately 50%. Microscopically the bacterial cell envelope appeared unchanged during the post‐ingestive period (3h).
CONDITIONS RELEVANT TO THE OCCURRENCE OF ACID‐FAST BACILLI IN SPHAGNUM VEGETATION
Authors: IRGENS LORENTZ M. , KAZDA JINDRICH , MÜLLER KLAUS , EIDE GEIR E.
Published: August 2010

Biotopes with intact sphagnum vegetation were studied in Naustdal, West Norway: the health district with the former highest leprosy incidence rates in Norway. Concentration of acid‐fast bacilli and concentration of non‐cultivable acid‐fast bacilli found in the vegetation fluid were compared with a series of variables related to the local environment and to the samples of vegetation. In bivariate analyses high concentrations were found in biotopes with orientation towards South, with a high coverage of vascular plants and with presence of Ericaceae. High concentrations were also found where dry weight of vegetation was high, where pH in the fluid was low and where dry weight of the fluid was high. In a multivariate analysis, log‐linear model, based on concentration of acid‐fast bacilli as the dependent variable and orientation, pH, dry weight of vegetation and dry weight of fluid as the independent variables, all two‐factor effects including the dependent variable were retained in the model. Furthermore, orientation versus dry weight of vegetation and dry weight of fluid versus dry weight of vegetation were retained.
YERSINIA PSEUDOTUBERCULOSIS AS THE CAUSE OF SEPTICAEMIA IN A PATIENT WITH LIVER CIRRHOSIS
Authors: GUNDERSEN TORSTEIN , NEESS HANS CHRISTIAN
Published: August 2010

Septicaemia caused by Yersinia pseudotuberculosis in a female patient, aged 22, is reported. She had suffered from a chronic active hepatitis for 14 years and had been treated with corticosteroids and azathioprine. The Y. pseudotuberculosis septicaemia responded well to treatment with doxycycline orally, but the patient died 2 weeks later because of excessive bleeding from varicous veins of the oesophagus.