bluuebunny/crossref_metadata_2025 huggingface dataset:
GROWTH INHIBITORY EFFECT OF MOUSE SERUM ON EUKARYOTIC CELLS IN A MICRO ASSAY
Authors: GUNDERSEN STEIN , JACOBSEN JORUNN , FUNDERUD STEINAR
Published: August 2010

Inhibition of cell growth by B6D2F1 (C57BI/6 × DBA/2) mouse serum in tissue culture wells confirming previous findings in the soft agar tumour colony assay is reported. The assay was time saving, more sensitive, and the amount of mouse serum used could in each experiment be reduced by 95% In addition non‐neoplastic cells ordinarily not forming colonies in the soft agar assay could be tested. Such cells were less sensitive to the growth inhibitory effect when compared to neoplastic cells.
BINDING OF PURIFIED Cl SUBCOMPONENTS, Cl INACTIVATOR AND THEIR COMPLEXES TO IMMOBILIZED HEPARIN
Authors: McKAY E. JOHN , JOHNSON ULF , LAURELI ANNA‐BRITA , MÂRTENSSON ULLA , SJÖHOLM ANDERS G.
Published: August 2010

Under specified conditions purified Clq, activated Cr and Cs and Cr‐Cs complexes were bound independently of Ca2+, to heparin‐Sepharose, and could be eluted by an increasing salt gradient. Zymogen Clr and Cls, Cr‐Cs complexes, C inactivator, and Cr‐Cs‐C inactivator complexes were not bound. However, at lower conductance Ca2+ independent binding of Clr occurred, which was utilized in the purification of Clr and Cls. In the presence of Clt (serum amyloid P component), Cls was firmly retained on heparin‐Sepharose, which was probably due to formation of a Cls‐Clt complex.
THE EFFECT OF SERUM AND PLASMA FROM HAEMODIALYSIS PATIENTS ON HUMAN MONONUCLEAR PHAGOCYTES CULTURED IN VITRO
Authors: WESSEL‐AAS TERJE
Published: August 2010

Human mononuclear phagocytes from healthy individuals were cultured in plasma and sera from normal persons and patients with chronic renal failure receiving haemodialysis. There was a marked detachment of macrophages from the glass coverslips when the cells were grown for 4 days in uraemic serum or plasma compared to normal serum. The ability of the macrophages to adhere to the glass coverslips was reduced when the cells were cultured in plasma from normal persons and uraemics subjected to systemic heparinization. However, the toxic effect of in vivo heparinization was much higher in the uraemics than in normal persons. Heparin added to normal and uraemic blood samples in vitro far in excess of in vivo heparinization did not influence the macrophage function to the same extent. Cell toxic substances seem to be produced as a consequence of systemic heparinization. These substances were not removed during 100 minutes of haemodialysis. Heparin added to pooled A Rh + serum in concentrations far above those present in plasma following in vivo heparinization had little adverse effect on the macrophage function.
SPECIFICITY OF LYMPHOCYTE STIMULATION IN VITRO BY MICROBIAL PREPARATIONS: IMPORTANCE OF ANTIGEN CONCENTRATION
Authors: MOGENSEN H. H. , ANDERSEN V.
Published: August 2010

Blood mononuclear cells were stimulated in vitro by 7 different microbial preparations, and thymidine incorporation was investigated in 7 groups of persons sensitized to the microorganisms and in 7 groups of controls. The sensitized persons were: 18 BCG‐vacinated, 13 with previous Mycoplasma pneumoniae pneumonia, 22 who had serum antibodies to Herpes simplex virus, 14 with previous typhoid fever, 13 with previous acute pyelonephritis caused by Eschrerichia coli, 6 with previous Haemophilus influenzae meningitis, and 15 tetanus‐vaccinated persons. Employing microbial preparations corresponding to the type of sensitization, higher responses were obtained with PPD, Mycoplasma pneumoniae. Herpes simplex virus, Salmonella typhi and tetanus toxoid in sensitized than in controls, but the responses to E. coli and H. influenzae were similar.

In each experiment a dose titration of the microbial preparation was carried out. The best separation between sensitized and non‐sensitized persons was obtained at low concentrations, giving submaximal stimulation. It is concluded that lymphocyte responses to many microbial preparations are combined of antigen‐specific components and of responses to cross‐reacting or polyclonally activating moieties, and that the antigen‐specific response is best investigated at low concentrations of these preparations.
ENHANCEMENT OF BACTERIAL UPTAKE AND KILLING IN LYMPHOKINE‐ACTIVATED HUMAN MONOCYTES
Authors: RÄSÄNEN LIISA , MUSTIKKAMÄKI U. P. , LEINIKKI P.
Published: August 2010

Studies were undertaken to establish whether lymphokines affect bacteria in a direct and/or an indirect fashion via monocytes. Lymphokine‐rich supernatants were generated by stimulating mononuclear cells with killed Bacillus subrilis bacteria. Various strains of bacteria were incubated in these culture supernatants and plated. Also. monocytes were incubated in the supernatants. after which their capacity to phagocytose and kill Staphvlococcus albus was measured. It was found that the culture supernatants did not contain activities exerting a direct effect on bacteria. They did. however, contain factors activating monocytes. The uptake and the killing of staphylococci increased 91% and 68% respectively. after three days incubation in lymphokine‐rich supernatants. The monocyte‐activating principle eluted in Sephadex G‐100 chromatography over a wide molecular weight range (>68000‐<23000) was not inactivated at 56°C and was reduced by L‐fucose. It thus shared the characteristics of human MIF or MAF.
QUANTITATION OF PROENZYME Clr‐Cls COMPLEXES IN ERUM BY ELECTROIMMUNOASSAY
Authors: Laurell A. B. , Mârtensson U. , Sjöholm A. G.
Published: August 2010

The electroimmunoassay for Clr‐Cls complexes was performed in two electrophoretic steps, the first in the presence of Ca2+ without antibody, and the second in the presence of EDTA with anti‐Clr in the gel. The results were reproducible and in agreement with semiquantitative estimates of Clr‐ClS complexes in normal and pathological sera on crossed immunoelectrophoresis.
INDUCTION OF LEUKOCHEMOTAXIS, PRIMARY SKIN INFLAMMATION AND LOCAL SHWARTZMAN REACTION BY NEISSERIA GONORRHOEAE EXTRACT
Authors: SVEEN K. , MÆLAND J. A.
Published: August 2010

The leukochemotactic activity of ultrasonicate of the N. gonorrhoeae strain 8551 was studied by in vitro and in vivo experiments. No chemotactic activity was observed with extract incubated in Gey's solution alone or with heat‐inactivated rabbit serum. Activity attracting polymorphonuclear cells was generated on injection of the extract into chambers implanted subcutaneously in rabbits, and in vitro when incubated with fresh rabbit serum, normal guinea pig serum or serum deficient in C4. Chemotactic activity was not observed on incubation with mouse serum deficient in C5. The extract showed pronounced activity in the preparing of rabbits for the local Shwartzman reaction and in inducing primary skin inflammatory reaction. Gonococci thus contain chemotaxigens that induce chemotaxin production by means of complement activation via the alternative pathway, and these or other components initiate strong inflammatory responses in vivo.
EXPERIMENTAL ENDOCARDITIS IN RABBITS
Authors: Gutschik ErnÖ
Published: August 2010

The synergistic action of penicillin and streptomycin was investigated on animals with experimental endocarditis, using the previously described model and four different strains of Streptococcus faecalis. Two strains represented a moderate and two strains a high level of resistance to streptomycin. The purpose was to determine the effect of the combined penicillin and streptomycin treatment, since previous in vitro investigations showed that strains highly resistant to streptomycin were also resistant to the combination of the drugs. Antibiotic treatment of the animals was carried out for 28 days, followed by a period of four weeks observation. The treatment resulted in a demonstrable effect against infection caused by the least streptomycin‐resistant strain, but was completely ineffective in rabbits infected with the strain homogeneously resistant to 8000 μg/ml streptomycin. The synergistic effect of penicillin and streptomycin towards strains within a range of streptomycin resistance of 2000 ‐ 8000 μg/ml could be predicted by the IC50 test, but not by MIC or the in vitro killing curve test for synergism. Besides the therapeutic results, this report also considers the following features: pathoanatomic and physiologic processes related to the number of viable bacteria in the endocardial vegetations; the influence of the proteolytic capacity of infecting strains; the development of congestive heart failure.
SHORT‐TERM ORAL CANDIDOSIS IN RATS, WITH SPECIAL REFERENCE TO THE SITE OF INFECTION
Authors: FISKER A. V. , SCHIØTT C. RINDOM , PHILIPSEN H. P.
Published: August 2010

Following a short‐term oral inoculation of Candida albicans in rats during tetracycline medication, the carriage of and infection by Candida organisms were investigated. After an initial high incidence, a rapid decline was registered. Five weeks following the first inoculation 33% of the animals showed a positive swab and 67% demonstrated pseudohyphal penetration of the oral mucosa. The most frequent sites of infection were the margin of the gingivae, the buccal mucosa, the buccal and lingual sulci and the tongue accounting for 98.8 % of all foci. The highly selective pattern of colonization is believed to be related to the surface characteristics of the epithelium and the nature of the keratin.
IN‐USE TESTS OF DISINFECTANTS
Authors: CHRISTENSEN EBBE AHRENSBURG , JEPSEN OLE BENT , KRISTENSEN HANNE , STEEN GRETHE
Published: August 2010

In two different laboratories three methods were applied for in‐use testing of 400 samples of disinfectants, primarily aldehyde and phenolic solutions, collected in 30 wards at 11 Danish hospitals. The results obtained with the Kelsey‐Maurer test, the membrane filtration technique, and a standardized challenge test were in complete accordance, however, the challenge test revealed a few more inefficient samples, than the two other methods. For routine use at hospital laboratories the choice between the Kelsey‐Maurer test or the modified Kelsey‐Maurer technique using membrane filtration may be guided by the available equipment. The design and the application of a challenge test and pertinent criteria for test strains are discussed. Only about 3 % of the samples failed to pass the tests, but a predominance (10%) of failures among the samples, received as number one in a series, underlines the didactic aspects of in‐use testing. The study demonstrates that suitable methods exist and may be of value when introduced in the local policy of controlling disinfectants.
RELIABILITY OF THE PLAQUE ASSAY TO DETERMINE THE SENSITIVITY OF NEISSERIA GONORRHOEAE TO THE BACTERICIDAL ACTIVITY OF NORMAL HUMAN SERUM
Authors: ØDUM LARS
Published: August 2010

A plaque assay for determination of the sensitivity of Neisseria gonorrhoeae to the complement‐dependent bactericidal activity of normal human serum was evaluated. The method was found to be rapid and easy to perform. All strains, which gave a positive result by the plaque assay, were serum‐sensitive in a quantitative assay, whereas only 78% of strains giving negative results by the plaque assay were true serum‐resistant. The growth of a few gonococcal strains was inhibited, i.e. formed plaques, after exposure 10 genuine as well as to heat‐inactivated normal human serum.
SPHINGOMYELINASE ACTIVITY OF STAPHYLOCOCCUS AUREUS STRAINS FROM RECURRENT FURUNCULOSIS AND OTHER INFECTIONS
Authors: HEDSTRÖM S. Å. , MALMQVIST T.
Published: August 2010

The sphingomyelinase (beta‐hemolysin) production by 180 Staphylococcus aureus strains was determined in a qualitative enzyme impression test (EIT) and all but 4 strains in a quantitative enzyme assay test (EAT) using 14C‐sphingomyelin as test substrates. A total of 59 strains (33%) were positive for enzyme production in the EIT. The highest frequency was found in strains isolated from recurrent furunculosis (45%) as compared with strains from chronic osteomyelitis, tropical pyomyositis and healthy nasal carriers (18, 8 and 19%, respectively). High producers of sphingomyelinase in EAT were mostly found among furunculosis strains, phage type 55 and/or 71. The furunculosis strains lysed by phages 3A and/or 3C mostly had a low sphingomyelinase production. In 3 families, high‐ and low‐producing strains of the same phage group were isolated from 2 different members of the same family. The high‐producing strains caused more intense skin lesions.
LONG‐TERM ORAL CANDIDOSIS IN RATS
Authors: FISKER A. V. , SCHIØTT C. RINDOM , PHILIPSEN H. P.
Published: August 2010

The aim of the study was to investigate the carriage and infection rate during continuous oral inoculation of Candida albicans in conventionalized SPF rats after initial tetracycline medication. During the 34‐week experiment 50% of the animals harboured Candida albicans in the mouth, whereas only 25 % of the animals demonstrated pseudomycelial penetration of the oral mucosa. More than ninety per cent of the candidal foci were found in areas covered by a less densely cornified epithelium and were mainly localized to the sulcular folds, the gingival margin and the cheek. Only the dorsal surface of the tongue showed foci with obvious signs of long‐standing candidal infection. The lingual papillae were lost and replaced by a flat‐surfaced parakeratotic epithelium showing irregular hyperplasia, acanthosis but no atypia. Reactive changes were found in the underlying lingual muscular layer.
DETECTION OF STAPHYLOCOCCUS AUREUS ANTIBODIES IN PATIENTS WITH S. AUREUS INFECTIONS AND IN NORMAL PERSONS, USING SOLID PHASE RADIOIMMUNOASSAY
Authors: CHRISTENSSON BERTIL , HEDSTRÖM SVEN ÅKE , KRONVALL GÖRAN
Published: August 2010

One hundred and thirteen patients with S. aureus infections, eight patients with non‐ S. aureus septicemia and 167 normal controls were investigated by solid‐phase radioimmunoassay for staphylococcal antibodies. All serum samples tested had measurable antibodies, including the normal controls. The test could differentiate the patient group with S. aureus endocarditis from patients with other S. aureus septicemia, as well as from normal controls, as the endocarditis group had significantly higher antibody levels. Patients with non‐bacteremic S. aureus infections, such as osteomyelitis and recurrent furunculosis, showed a wide range of antibody levels, 1/3 and 1/4 of the patients, respectively, showing high levels comparable to the endocarditis patients. Among normal controls, high antibody levels were found in 13 per cent.
METHANE AND HYDROGEN PRODUCTION BY HUMAN INTESTINAL ANAEROBIC BACTERIA
Authors: McKAY L. F. , HOLBROOK W. P. , EASTWOOD M. A.
Published: August 2010

The gas above liquid cultures of a variety of human intestinal anaerobic bacteria was sampled and analysed by headspace gas chromatography. Hydrogen production was greatest with strains of the genus Clostridium, intermediate with anaerobic cocci and least with Bacteroides sp. Very few strains produced methane although small amounts were detected with one strain of B. thetaiotaomicron, C. perfringens and C. histolyticum. There may be a relationship between these anaerobic bacteria and several gastrointestinal disorders in which there is a build up of hydrogen or methane in the intestines.
IMMUNOCHEMICAL STUDIES OF LIPOPOLYSACCHARIDE AND PARTIALLY DEGRADED LIPOPOLYSACCHARIDE FROM BACTEROIDES FRAGILIS IPL E323
Authors: HOFSTAD TOR
Published: August 2010

A serologically heterogeneous lipopolysaccharide (LPS) was prepared from B. fragilis IPL E323 by phenol‐water extraction and purification by ultracentrifugation. The LPS was split by hydrolysis with 1 per cent acetic acid into an acid‐soluble polysaccharide and insoluble material. Gel filtration of the acid‐soluble material on Bio‐Gel P‐60 gave a high‐molecular‐weight fraction eluted with the void volume (Vo), which was serologically heterogeneous, and low‐molecular‐weight materials eluted at 2.5 × Vo and 2.7 × Vo. Some material was also eluted at 2.9–3.0 × Vo. The oligosaccharides eluted at 2.5 × Vo and 2.7 × Vo showed an antibody‐neutralizing capacity similar to that of the parent LPS. Galactose, glucose and rhamnose were the only sugars present in these fractions. The material eluted at 2.9–3.0 × Vo, which contained the same neutral sugars, but at another molar ratio, was serologically inactive. Similar results were obtained when LPS from three other B. fragilis strains were treated in the same way.
THE USE OF FROZEN ERYTHROCYTES IN MACROPHAGE STUDIES
Authors: MYHRVOLD VESLEMØY , JONSEN JON , MØRLAND BERJT
Published: August 2010

The attachment of red cells to mouse peritoneal macrophages in vitro was tested with erythrocytes (from sheep and man) which had been subjected to different cryoprotective agents and freezing procedures. The experiments showed that with dimethylsulfoxide (DMSO) as the cryoprotective agent no difference in macrophage attachment was seen whether the erythrocytes were frozen or not. With the other cryoprotectants tested, macrophages were more efficient in attaching frozen than unfrozen erythrocytes. This was the case with erythrocytes from both sheep and man. Similar results were obtained with fresh (one week) and old (two weeks) erythrocytes.
THREE TYPES OF GROWTH INHIBITION AMONG STRAINS OF NEISSERIA MENINGITIDIS ISOLATED FROM PATIENTS IN NORWAY
Authors: JYSSUM K. , ALLUNANS J.
Published: August 2010

A survey has been made of Neisseria meningitidis strains isolated from patients in order to determine the prevalence of diffusible growth inhibitory substances active against other meningococci. Three types of growth inhibitory activity could be distinguished. The first type was released in cultures of nearly all strains after treatment with chloroform vapour. This activity inhibited all meningococci tested, including the donor strain. The properties were similar to those of the non‐specific growth inhibitors observed among most strains of N. gonorrhoeae. The second type was demonstrated in cultures from four strains among 215 strains tested and may be present in a fifth strain. Bactericidal activity with high strain specificity was spontaneously released from cultures of the four strains. This type of activity was found to fit the description of a bacteriocin. The third type of inhibition was observed in one strain among the 215 strains tested. Cultures of this strain spontaneously released bacteriostatic activity. Products from the strain could inhibit almost all meningococcal strains except the donor strain itself. This activity was not entirely blocked by bovine serum albumin; it was not abolished by pronase and it was not stopped by dialysis membranes with cut‐off 12000.
GENTAMICIN‐RESISTANT STAPHYLOCOCCUS AUREUS STRAINS AND THEIR SUSCEPTIBILITY TO OTHER AMINOGLYCOSIDES
Authors: BANG JØRGEN , ROSDAHL VIBEKE T. , BENTZON MICHAEL WEIS , ROSENDAL KIRSTEN
Published: August 2010

Forty‐six Staphylococcus aureus strains with an IC‐50 value to gentamicin (G) of 1 μg/ml or more were investigated for their IC‐50 values to kanamycin (K), tobramycin (To), sisomicin (Si), streptomycin (S), netilmicin (Net) and amikacin (Ami). Correlation coefficients greater than 0.98 were found between the values of G and those of K, To, Si, Net and Ami, whereas a negative correlation was found between those of G and S. As the break‐points between susceptible and resistant strains were defined as 1 μ/ml to G, To and Si, 2 μ/ml to Net, 2.5 μ/ml to K and Ami and 3 μ/ml to S, all the 46 strains were also resistant to K, To and Si. A total of 15 strains were resistant to Net, 30 to Ami and 18 to S. All the strains were examined for their susceptibility to the seven aminoglycosides by three disc‐diffusion methods: the 20‐hours' pre‐diffusion method, the Biodisk paper‐disc method and Rosco Neo‐sensitabs. Satisfactory agreement was found between the IC‐50 values and the placing into four susceptibility groups by these three methods, when susceptibility to G, K, To, Si and S was investigated. The three disc‐diffusion methods evaluated susceptibility to Net identically with the majority of strains ‐ susceptible as well as resistant ‐ in group 2, but susceptibility to Ami was estimated differently by the three methods. The problems may be caused by the differences in the break‐points chosen and influenced by the »clustering« of the various zone diameters around the breakpoints. For Net and Ami a better correlation between the MIC/IC‐50 values and the groups of susceptibility obtained by the disc‐diffusion methods is needed.
DEOXYRIBONUCLEIC ACID RELATEDNESS AMONG SPECIES OF RAPIDLY GROWING MYCOBACTERIA
Authors: BAESS INGA
Published: August 2010

The DNA‐DNA homology percentages obtained in this study indicate that M. smegmatis, M. phlei, M. fortuitum, M. peregrinum, M. senegalense, M. farcinogenes, M. chelonei, M. parafortuitum, M. vaccae, M. diernhoferi and M. aurum are separate species. Taxonomically there is no justification for the designation M. fortuitum complex, and M. peregrinum should be revived as an independent species. The type strains of M. parafortuitum, M. vaccae, M. aurum and the non‐valid M. diernhoferi are so distinct from each other that they should not be combined.
BINDING OF CLOSTRIDIUM PERFRINGENS ENTEROTOXIN TO HEPATOCYTES, SMALL INTESTINAL EPITHELIAL CELLS AND VERO CELLS
Authors: JARMUND TORE , TELLE WENCHE
Published: August 2010

Clostridium perfringens enterotoxin binds specifically to hepatocytes, Vero cells and rat intestinal epithelial cells, and causes membrane damage visible as »bubble« formation. Fluorescein‐labelled enterotoxin also binds specifically to the same cell types. 125I labelled enterotoxin shows one class of binding sites on both Vero and rat intestinal epithelial cells. The number of binding sites decreases along the rat intestine, but the affinity constant is the same in different parts of the intestine.
ENZYME‐LINKED IMMUNOSORBENT ASSAY (ELISA) FOR ANTIBODIES AGAINST CAMPYLOBACTER JEJUNI, AND ITS CLINICAL APPLICATION
Authors: WALDER MATS , FORSGREN ARNE
Published: August 2010

Antibody response to Campylobacter jejuni/coli (CJC) was investigated, using an enzyme‐linked immunosorbent assay, ELISA. With a mixture of lipopolysacharide from two CJC strains as antigen in ELISA, all 24 tested rabbit anti‐CJC sera showed high antibody levels. However, only 70% of sera from patients with Campylobacter enteritis demonstrated an antibody response against the combined LPS antigen, using paired sera. In addition, the results obtained suggested non‐specific binding of human immunoglobulin. When 24 formalinized whole CJC bacteria were used as antigen in ELISA, all corresponding rabbit antisera reacted with one strain (M14). Essentially no unspecific binding of human immunoglobulin was obtained. Antibodies were detected in sera from healthy blood donors and at a lower level in sera from children, suggesting early immunization. In 67 enteritis patients with positive stool cultures for CJC, a significantly increased level of IgG antibodies could be detected in single or paired serum samples from 82% of the patients. An IgG titre increase occurred early in the course of infection, suggesting a boosting of an earlier immunization. IgM antibodies could be detected in the same sera in 77% of the patients. Considering both IgG and IgM analyses of the enteritis sera, 94% of the patients were positive in Campylobacter ELISA serology compared with only 5% of healthy controls.
STAPHYLOCOCCAL ENTEROTOXIN A, B, AND C PRODUCED BY COAGULASE‐NEGATIVE STRAINS WITHIN THE FAMILY MICROCOCCACEAE
Authors: OLSVIK ØRJAN , FOSSUM KÅRE , BERDAL BJøRN P.
Published: August 2010

Clinical isolates of coagulase‐negative cocci identified as members of the family Micrococcaceae, were tested for production of enterotoxin A, B, and C in broth culture by the use of an ELISA method. Out of 117 strains tested, 12 were enterotoxin producers, of which 4 strains belonged to the genus Staphylococcus and 8 strains to the genus Micrococcus. Except for one strain producing all three types of enterotoxin, the strains produced toxins of type A (5 strains) or type C (6 strains).
DETECTION OF CLOSTRIDIUM PERFRINGENS TYPE A ENTEROTOXIN BY ELISA
Authors: OLSVIK øRJAN , GRANUM PER EINAR , BERDAL BJØRN P.
Published: August 2010

A four‐layer sandwich ELISA was developed for the detection of Clostridium perfringens enterotoxin. This ELISA method was sensitive down to 0.1 ng/ml of purified enterotoxin in trypticase soy broth, and 1.0 ng/ml of enterotoxin in heterogeneous solutions such as meat products and faeces.
A RAPID METHOD TO PRODUCE A SENSITIVE LIMULUS AMOEBOCYTE LYSATE (LAL)
Authors: TVEDE MICHAEL , BAEK LEIF
Published: August 2010

An improved method for preparing Limulus amoebocyte lysate (LAL) is described and compared with two other well‐known procedures. In five Limuli, three different bleeding procedures and three different cell rupture methods were studied. Increased sensitivity of LAL was accomplished by avoidance of the anticoagulant N‐ethylmaleimid (NEM) in the bleeding procedure, optimal methods for mechanical cell rupture and use of pyrogen free conditions. Reaction of LAL with as little as 10–15 gram Lipopolysaccharide (LPS) per ml was generally obtained. To evaluate a possible explanation for the differences in reactivity of LAL between different Limuli, found in one experiment, six Limuli were bled, and the pH and the concentration of protein, Ca2+, Mg2+, Cu2+, Na+ and K+ were determined in LAL and cell‐free hemolymph. Inter and intra batch variations were found in LAL, but there was no correlation between the sensitivity of LAL and the content of the above mentioned constituents in LAL and cell‐free hemolymph. Experiments with use of NEM in the bleeding procedure and addition of NEM to homogenized cells in different concentrations, showed that NEM inhibits the reactivity of LAL to LPS. It is concluded that the modified method of producing LAL by bleeding without NEM and by using optimal methods for mechanical cell rupture is quick, simple and produces a very sensitive reagent for the Limulus test.
THE RECOVERY OF ANAEROBIC BACTERIA FROM SWABS IN THREE TRANSPORT SYSTEMS Statistical Evaluation by Application of a Variance Component Model
Authors: HOFFMANN STEEN , JENSEN ANDERS MØRUP , JUSTESEN TAGE
Published: August 2010

The recovery of six anaerobic species from swabs in three transport systems was quantitatively evaluated. The test strains were Bacteroides fragilis, B. melaninogenicus ss. intermedius, Fusobacterium necrophorum, Peptostreptococcus anaerobius, Eubacterium lentum, and Clostridium ramosum. The transport systems were a charcoal‐impregnated cotton swab in modified Stuart's transport medium (MS), or a plain cotton swab in either a dry aerobic tube (DA) or an aerobic agar tube (AA). Swabs were charged with a known number of organisms of the test strain and inserted in the appropriate transport systems. Immediately hereafter the swabs were transferred to glass tubes with reduced buffer. After vigorous shaking, aliquots from the buffer were seeded onto blood agar plates, and the number of colony forming units (CFU) was counted after incubation. The number of CFUs from independent replications had a variation that was too large to be accounted for by the Poisson distribution. The probability of recovery (POR) was defined as the number of CFU recovered from a swab as a percentage of the original inoculum. The logarithms of the POR values were analyzed with a variance component model. This showed that estimated values of POR were significantly higher in DA (44%) than in AA (23%), while the value for MS (33%) did not differ significantly from those for AA or DA. It is concluded that in MS, friction between swab and medium does not contribute significantly to bacterial recovery loss, as compared to AA and DA.
BINDING OF AGGREGATED IgG Fab‐FRAGMENTS AND LIGHT CHAINS TO SOME GROUP A, C and G STREPTOCOCCI
Authors: SCHALÉN CLAËS , ZÄTTERSTRÖM ULF , SVENSSON MAJ‐LIS , CHRISTENSEN POUL
Published: August 2010

Receptors for IgG Fc in many group A, C and G streptococci have been reported previously. We now describe a reaction between group A, C and G streptococci and IgG Fab‐parts, not involving the antigen combining sites. The bacteria proved to bind aggregated, but not monomeric, IgG Fabfragments, indicating that multivalent interaction was a prerequisite for the binding to occur. Most of the strains exhibiting affinity for aggregated IgG Fab could also interact with aggregated acid and/or Λ light chains. The capacity of the single strains to bind aggregated IgG Fab did not correlate with presence of IgG Fc‐receptor activity. Furthermore, in contrast to streptococcal Fc‐receptors, the streptococcal structure reacting with Fab was highly sensitive to trypsin as well as phosphatase treatment. The binding of aggregated Λ‐chains to each of two strains tested was inhibited by liquoid and aggregated human albumin, suggesting that lipoteichoic acid and/or M protein are responsible for the binding of IgG Fab‐fragments. A pronounced binding of aggregated IgG Fab, but not light chains, to Staphylococcus aureus, strain Cowan I, was also found. Various other bacterial species were tested for binding of the aggregates, with negative results.
THE GENETIC CONTROL OF VIRULENCE IN GROUP A STREPTOCOCCI
Authors: RAVDONIKAS LARISSA E.
Published: August 2010

Transfer of five plasmids was studied in 30 different mating systems, involving streptococci of groups A. D and H. The erythromycin resistance marker (Emr) of all five plasmids was transferable at frequencies ranging from 8times107 to 2times10‐4. All original donor strains except SM60 (pERL1) contained phage activity, but evidence was obtained favouring conjugation over transduction as the mechanism of transfer. The process was rec‐independent. The transconjugants were able to serve as donors of the Emr‐marker in secondary matings. A shortened derivate (pSM10) of the plasmid pSM10419 could also be transferred. Finally, the presence of the plasmid pSM15346 influenced the expression of the capacity to adhere to human epithelial cells and the resistance to UV‐light of the host, whereas anti‐phagocytic activity and production NADse and of opacity factor was unaffected by the plasmid.
BACTERIAL HYDROPHOBICITY MEASURED AS PARTITION OF PALMITIC ACID BETWEEN THE TWO IMMISCIBLE PHASES OF CELL SURFACE AND BUFFER
Authors: MALMQVIST TORSTEN
Published: August 2010

Bacterial hydrophobicity was measured as the affinity of palmitic acid to the cell surface. Cell surface and buffer were regarded as two immiscible phases with different affinity for the fatty acid. After equilibration of the system, the partition quotient (PQ) between the two phases was calculated. The bacteria hydrophobicity was expressed as the amount of cell mass required to give a partition quotient of 10 between amount of fatty acid bound to cell surface and amount of fatty acid in buffer (PQ 10). This system permits measurement of changes in hydrophobicity during bacterial growth as shown for Staphylococcus aureus, strain V 8. The hydrophobicity of this bacterium increased 4–5 times during the exponential growth‐phase of the culture. In the stationary growth‐phase there was a loss of hydrophobicity, which continued for at least 48 hours, linearily with time. The system was also tested with a Salmonella typhimurium strain and its rough mutant. The results were consistent with findings in other test systems measuring the hydrophobicity of these bacteria.
THE Ibc PROTEINS OF GROUP B STREPTOCOCCI: TRYPSIN EXTRACTED α ANTIGEN AND DETECTION OF THE α AND β ANTIGENS
Authors: BEVANGER LARS , IVERSEN OLE‐JAN
Published: August 2010

In order to study the antigen composition of different group B streptococcal strains as regards the Ibc proteins α and β, different methods for extraction were compared. Bacteria of the serotype Ic strains A909 and 335 were treated with HCl, urea, Triton‐X‐100, EDTA, or trypsin. Extraction with HCl was most efficient for the preparation of the β antigen; trypsin extraction for the α antigen. The trypsin‐extracted αA909 and α335 antigens showed similar characteristics. Double‐diffusion analysis showed a reaction of identity; on Sephacryl S‐200 filtration both appeared with peak activity at a Kav of 0.25 and on SDS‐PAGE the purified preparations showed peak antigenic activity corresponding to 65,000 daltons. Hydrolysis of the α antigens with HCl induced minor changes in the SDS‐PAGE patterns and reduction in antigenic activity. Both of the α antigens were immunogenic in rabbits. Antisera to the α335 and βA909 antigens were used to evaluate indirect FAT, CA, RIE, and CIE, in the detection of the antigens in 20 group B isolates. The results indicated that as a single test for the detection of α and β antigens in group B streptococci, FAT or RIE should be preferred.
RAPID DETECTION OF HERPES SIMPLEX VIRUS AND VARICELLA‐ZOSTER VIRUS IN CLINICAL SPECIMENS BY THE USE OF STAPHYLOCOCCUS AUREUS RICH IN PROTEIN A
Authors: MOGENSEN SØREN C. , DISHON THEODOR
Published: August 2010

Herpes simplex virus (HSV) type 1 and type 2 and varicella‐zoster virus (VZV) were detected in cytospin preparations from clinical material by using specific antisera and Staphylococcus aureus, Cowan 1 strain, rich in protein A (SRA). Virus was isolated in tissue culture from 22 of the 30 specimens submitted for examination. Eighteen isolates showed cytopathic effect characteristic of HSV infection and 4 of VZV. In the cytospin preparations of the same samples HSV was detected in 15, two contained too few cells to allow a reliable diagnosis and one sample was negative when the SRA reagent was used. In the cytospin preparations of 2 of the 8 samples, which did not show cytopathic effect on isolation in tissue culture, HSV was detected by the SRA. This points to the possible presence of inactive virus in the specimens. All 4 cases of VZV infection were diagnosed correctly with the staphylococcal reagent. No reaction was observed between VZV antigens and rabbit anti‐HSV sera. Cells in which viral infection was detected by specific antisera and SRA did not show staphylococcal adherence to their surface after interaction with normal rabbit or normal human serum. Similarly, cells from healthy donors, treated with positive and negative sera were found negative. The method is easy to perform and results can be obtained within three hours from the time specimens are received at the laboratory. Its use offers a rapid diagnosis in suspected cases of herpetic infections in which early therapy is recommended.
LEGIONELLA EXTRACELLULAR PROTEASE ACTIVITY ON CHROMOGENIC PEPTIDES: A SIMPLIFIED PROCEDURE FOR BIOCHEMICAL ENZYME IDENTIFICATION
Authors: Berdal Bjørn P. , Olsvik Ørjan
Published: August 2010

Legionella strains produce extracellular proteases. One method to demonstrate these is through the activity of broth culture filtrates on para‐nitroanilide (pNA)‐derivatized peptides. Previously, this method has comprised a 100‐times concentration of the filtrates, in order to bring the protease activity, as measured by the liberation of free pNA from hydrolysed peptides, up to easily recordable values. By introducing a diazotation step, the sensitivity of the test has been increased sufficiently to omit the time‐consuming concentration procedure. Accordingly, the analysis of extracellular Legionella proteases by pNA‐derivatized peptides has become rapid and straight‐forward.
PHYSICO‐CHEMICAL SURFACE PROPERTIES OF SHIGELLA SONNEI
Authors: EDEBO L. , MAGNUSSON K.‐E. , STENDAHL O.
Published: August 2010

In partition in two‐phase systems as well as in hydrophobic and ion exchange chromatography a number of Sh. sonnei isolates with different phage patterns showed similar physico‐chemical surface properties. All the isolates displayed hydrophobicity and a small negative charge. In this way the shigellae were different from salmonella S‐strains and E. coli strains associated with infantile diarrhoea which have shown hydrophilic properties and nearly no charge. They were also different from E. coli strains with typical K‐antigen often grown from patients with septicemia and upper urinary tract infection, which have shown hydrophilic properties and a great negative charge. However, the Sh. sonnei isolates were similar to E. coli strains belonging to certain serogroups which have been grown from patients with dysentery‐like diseases. The results indicate that physico‐chemical surface properties are related among enterobacteria belonging to different genera which have been grown from similar types of infections.
ADHERENCE AND TOXICITY OF YERSINIA ENTEROCOLITICA 0:3 AND 0:9 CONTAINING VIRULENCE‐ASSOCIATED PLASMIDS FOR VARIOUS CULTURED CELLS
Authors: VESIKARI TIMO , SUNDQVIST CARIN , MÄKI MARKKU
Published: August 2010

Plasmid (47 and 44 Mdal, respectively) containing strains of Yersinia enterocolitica 0:3 and 0:9 adhered to and were toxic for HEp‐2 human epithelial and Y‐1 adrenal cells in vitro. At 37 °C, but not at room temperature, the adhesion of the bacteria lead to rounding and partial detachment of the cultured cells. UV‐inactivated plasmid‐positive Y. enterocolitica were neither adherent nor toxic for the cells but were readily endocytosed by HEp‐2 cells. The adherence of plasmid‐positive Y. enterocolitica 0:3 and 0:9 on epithelial cells may be pathogenetically important as an initial step for intestinal colonization, and possibly in Y. enterocolitica‐induced diarrhoea. Plasmid‐positive Y. enterocolitica also adhered to the surface of cultured human macrophages and were apparently not phagocytosed as effectively as the plasmid‐negative derivatives of the same bacteria. Thus resistance to phagocytosis may form an additional plasmid‐dependent virulence property of Y. enterocolitica 0:3 and 0:9.
PNEUMOCOCCAL MENINGITIS AND BACTERAEMIA IN DANISH CHILDREN 1969–1978
Authors: PEDERSEN FREDDY KARUP , HENRICHSEN JØRGEN
Published: August 2010

The incidence of pneumoccal meningitis in Danish children during 1969–1978 was estimated to be 2.1/year/100,000 children from 0 to 14 years old. Fifty‐five per cent of 146 children with pneumococcal meningitis and 61% of 61 with bacteraemia were below 2 years of age. Mortality from meningitis was 13% and from bacteraemia 7%. Of the children with meningitis, 14% had sequelae at the time of discharge from the hospital. Sequelae were not seen after bacteraemia. Among 277 pneumococcal isolates from spinal fluid and blood from Danish children during 1969–1978, serotypes 14, 18C, 6A + 6B, 23F, 7F and 19F, in that order of frequency, were the most common ones, accounting for 69% of all isolates. Serotypes included in current 14‐valent pneumococcal polysaccharide vaccines made up 81% of all types, when types 6A and 6B are considered together (because it has been shown that they offer cross‐protection).
THE IN VITRO ACTIVITY OF GENTAMICIN, TOBRAMYCIN AND NETILMICIN AGAINST 500 CLINICAL ISOLATES OF BACTERIA
Authors: DIGRANES ASBJØRN , DIBB WILLIAM L. , BENONISEN EVA , ØSTERVOLD BIRGIT
Published: August 2010

The in vitro activities of the three aminoglycoside antibiotics, gentamicin, netilmicin and tobramycin have been compared against 500 isolates of Enterobacteriaceae, Pseudomonas aeruginosa and Staphylococcus aureus. An agar dilution method was employed with three sensitivity media: Iso‐Sensitest Agar, Mueller‐Hinton Agar and PDM‐Antibiotic Sensitivity Medium. All three aminoglycosides were highly active against S. aureus (MIC ≤ 0.5 mg/l) and the majority of Enterobacteriaceae (MIC90 approx. 1 mg/l). Tobramycin showed the highest activity against P. aeruginosa (MIC ≤ 1 mg/l). No major difference in measured MIC were found on the three media. Gentamicin and netilmicin were somewhat less active against P. aeruginosa on Mueller‐Hinton Agar. MICs for tobramycin against Enterobacteriaceae were a little higher on PDM than on the other two agars. Our results show that measured MIC varied very little on the three sensitivity media. All media are suitable for routine use, provided that control strains are employed.
N‐FORMIMIDOYL THIENAMYCIN: IN VITRO COMPARISON WITH CEFOXITIN AND TOBRAMYCIN AGAINST CLINICAL, BACTERIAL ISOLATES
Authors: DIGRANES ASBJØRN , DIBB WILLIAM L. , BENONISEN EVA
Published: August 2010

The in vitro activity of the novel β‐lactam antibiotic, N‐formimidoyl thienamycin (N‐f thienamycin) has been compared with those of cefoxitin and tobramycin. An agar dilution method was employed. N‐f thienamycin was active against all Enterobacteriaceae isolates (MIC ≤ 4 mg/l). All Pseudomonas aeruginosa isolates were inhibited by 2 mg/l. N‐f thienamycin was also active against Acinetobacter calcoaceticus (96 per cent inhibited by 0.5 mg/l) and Gram‐positive cocci. All enterococci were inhibited by 2 mg/l. The drug was active against Haemophilus influenzae (MIC ≤ 1 mg/l) and the Bacteroides fragilis group (MIC ≤ 0.5 mg/l). Cefoxitin was inactive against most Enterobater and A. calcoaceticus isolates and all P. aeruginosa and enterococcal isolates. Tobramycin was virtually inactive against Gram‐positive cocci other than Staphylococcus aureus. N‐f thienamycin thus has a broad spectrum of in vitro activity, greater than that of cefoxitin and tobramycin, and may therefore be useful in the treatment of serious infection, particularly when the aetiology is unknown.
POLYMYXIN SUSCEPTIBILITY IN STAPHYLOCOCCI DIFFERENTIATING COAGULASE‐POSITIVE AND COAGULASE‐NEGATIVE STRAINS
Authors: HELTBERG OLE , BRUUN BRITA
Published: August 2010

47 staphylococcal reference strains representing 13 species were tested for polymyxin sensitivity using tablet and disc diffusion methods. Corresponding MIC and IC50 values were determined with a plate dilution assay. Coagulase‐positive strains were found to be more resistant towards polymyxin, and could thereby be separated from coagulase‐negative strains. Furthermore, 100 recently isolated staphylococci from clinical specimens were tested, and again the coagulase‐positive strains could be identified by their smaller tablet inhibition zones. We conclude that the polymyxin test is an aid in the fast differentiation of staphylococci in laboratories performing primary sensitivity tests.
PREVALENCE AND MOLECULAR EPIDEMIOLOGY OF ANTIBIOTIC‐RESISTANT SALMONELLA TYPHIMURIUM AND SALMONELLA DUBLIN IN DANISH CATTLE
Authors: JØRGENSEN SIGRID TUE
Published: August 2010

Among 130 strains of S. typhimurium and 191 strains of S. dublin, all from cattle, 80% and 63%, respectively, were resistant to one, two or three antibiotics. Mono‐resistance to sulphonamides was most common. Plasmid load was analysed by conjugation, transformation, extraction of plasmid DNA and subsequent electrophoresis in agarose gels. Plasmid DNA from 38 strains was further analysed by restriction with endonuclease EcoR1. On the basis of this, the strains were classified into four groups. Two groups held S. typhimurium, one held S. dublin and one group held both serotypes. This suggests that dissemination of strains and plasmids mainly occurs through clonal spread of strains. However, plasmid transfer per se also takes place, as exemplified by the fact that indistinguishable plasmids were found in two different serotypes. Strains of one group had contaminated a water‐course. Strains of this group were furthermore isolated from humans in the same area as the infected cattle. Strains of this group had an R pattern and a phage‐type similar to the R pattern and phage‐type of the early isolates of a strain that became epidemic in British cattle. It is discussed whether Denmark, which was previously almost free of cattle salmonellosis, is experiencing the first warnings of an epidemic similar to the one in the UK.
A ROTAVIRUS STAPHYLOCOCCAL CO‐AGGLUTINATION TEST
Authors: SKAUG KJELL , FIGENSCHAU KARL JON , ØRSTAVIK IVAR
Published: August 2010

A simple and rapid staphylococcal co‐agglutination (SA) test for detection of rotavirus in human faecal specimens is described. A suspension of protein A‐containing staphylococci coated with a rabbit hyperimmune serum against the rotavirus strain of calf diarrhoeae virus was used as reagent. Before the SA test, the faecal specimens were absorbed with a suspension of uncoated staphylococci. 34 of 36 rotavirus immune electron microscopy (IEM) positive samples showed a positive SA test, whereas none of 41 IEM negative specimens agglutinated the staphylococcal reagent. The SA test was as sensitive as an enzyme‐linked immunosorbent assay (Rotazyme®) and in our hands more sensitive than a latex agglutination test (Rotalex®).
A VIRUS‐LIKE PARTICLE ASSOCIATED WITH PSORIASIS
Authors: DALEN A. B. , HELLGREN L. , IVERSEN O.‐J. , VINCENT J.
Published: August 2010

Virus‐like particles were demonstrated by electron microscopy of specimens from psoriatic plaques. Cell cultures established from plaques released particles, showing the morphological features of a retrovirus, for a prolonged period. The particles had a buoyant density of 1.17 g/cc and contained a surface protein of Mr 70,000 which bound to concanavalin A and therefore probably was of glycoprotein nature. A major internal protein of Mr 30,000 and two minor proteins of Mr 18,000 and 15,000 were detected. The composition of the proteins therefore resembled that of murine C‐type retrovirus. Patients with psoriasis release virus‐like particles in their urine which have a different morphology to the particles from cell cultures. A similar difference could be observed in particles from cell cultures after treatment with normal urine. Patients with psoriatic arthritis had serumimmune complexes. The complexes contained distorted particles which could not be identified as virions on a morphological basis. A radio immunoassay was performed which demonstrated common antigens in the virus‐like particles isolated from psoriatic urines, immune complexes and cell cultures.
ACIDIC METHANOLYSIS V. ALKALINE SAPONIFICATION IN GAS CHROMATOGRAPHIC CHARACTERIZATION OF MYCOBACTERIA: DIFFERENTIATION BETWEEN MYCOBACTERIUM AVIUM‐INTRACELLULARE AND MYCOBACTERIUM GASTRI
Authors: LARSSON LENNART
Published: August 2010

Mycobacterium avium‐intracellulare and M.gastri were analyzed with capillary gas chromatography after each strain had been subjected to acidic methanolysis or to alkaline saponification followed by methylation. Prominent peaks of myristic, palmitoleic, palmitic, oleic, stearic and tuberculostearic acids were found in the chromatograms of both species, whereas 2‐octadecanol and 2‐eicosanol were detected only in M. avium‐intracellulare. In initial runs, both of the derivatization principles yielded virtually identical chromatograms for a given strain. After repeated injections of extracts from alkaline saponification, however, the alcohol peaks showed pronounced tailing and finally almost disappeared from the chromatograms. This disadvantage, which was not observed when only acid methanolysis was used, could be overcome with trifluoroacetylation. Restored peak shape of the underivatized alcohols could be achieved by washing the cross‐linked stationary phase in the capillary tubing with organic solvents. The study demonstrated the importance of conditions which enable separation of 2‐octadecanol and 2‐eicosanol when gas chromatography is used for species identification of mycobacteria.
PATHOGENICITY OF 42–44 MDAL PLASMID POSITIVE AND NEGATIVE YERSINIA PSEUDOTUBERCULOSIS I AND YERSINIA ENTEROCOLITICA 0:8 AND 0:9 STUDIED IN THE GUINEA PIG EYE MODEL (SERÉNY TEST)
Authors: MÄKI MARKKU , VESIKARI TIMO , RANTALA IMMO , SUNDQVIST CARIN , GRÖNROOS PAUL
Published: August 2010

When virulence plasmid (42–44 Mdal) positive and negative Yersinia pseudotuberculosis I and Yersinia enterocolitica 0:8 and 0:9 were tested in the guinea pig eye model the following order of pathogenicity was observed: Plasmid‐positive Y. pseudotuberculosis I (death of the animal) > plasmid‐negative Y. pseudotuberculosis I plasmid‐positive Y. enterocolitica 0:8 (severe conjuntivitis) > plasmid‐positive Y. enterocolitica 0:9 (mild conjuntivitis) > plasmid‐negative Y. enterocolitica 0:8 and 0:9 (no effect).