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Biomedical subjects

K Sveen

Publications and source records attributed to K Sveen.

At least 37 records · Page 2Linked to original sources
PubMed1980

Effects of a chemotactic factor and Bacteroides fragilis lipopolysaccharide on bone resorption in tissue culture.

Release of previously incorporated 45Ca from fetal rat bone in tissue culture was stimulated by preparations of the polymorphonuclear leukocyte chemotactic factor isolated from lipopolysaccharide (LPS)-induced inflammatory exudate in rabbits as well as by Bacteroides fragilis LPS. High concentrations of released hydroxyproline and lactate seemed to correlate well as a high percentage of 45Ca liberated into the culture medium. An active bone resorption was stimulated by a concentration of 1 microgram/ml of the chemotactic factor. The peak in amount of released 45Ca was at a concentration of 5 micrograms/ml of the chemotactic factor (LPS-CF) as well as of the LPS preparation, whereas the parathyroid hormone was most active at 1 IU/ml. Their effect was connected with the formation of osteoclasts. Neither LPS-CF nor LPS stimulated a release of 45Ca or hydroxyproline from heat-devitalized bones. Heparin added to LPS-CF did not enhance its resorptive potential, whereas when added to LPS it had a synergistic effect. It is suggested that the bone resorptive effect exerted by LPS may be caused by chemotactic factors elaborated by activation of the complement system, and that these factors may be of importance in the pathophysiology of periodontal disease.

Animals↗
PubMed1979

Effect of the addition of a vasoconstrictor to local anesthetic solution on operative and postoperative bleeding, analgesia and wound healing.

A clinical study of local anesthetic solutions with and without epinephrine was conducted involving 32 healthy adults requiring removal of bony impacted mandibular third molars. The time elapsing from the administration of the anesthetic solution until analgesia was obtained was significantly shorter in the vasoconstrictor group (P less than 0.001). Additional anesthetic was necessary in 44% of the patients in the control group. The blood loss in the vasoconstrictor group was significantly lower (P less than 0.001) than in the group receiving anesthetic solution without the vasoconstrictor. No statistically significant difference in operation time between the groups was found, although the profuse bleeding in the control group impeded to some extent the surgical procedure. A positive correlation coefficient between operation time and blood loss of r = 0.65 in the vasoconstrictor group (P less than 0.006) and r = 0.77 in the control group (P less than 0.001) was found. Hemorrhage occurring 24 h postoperatively was recorded in 37% of the subjects in the vasoconstrictor group, and of these 83% revealed a healing of the socket by second intention.

Adolescent↗
PubMed1979

Incomplete branchial arch syndromes, branchial cleft cyst and vascular hamartoma in a patient with multiple neurofibromatosis.

A case report with simultaneous occurrence of neurofibromatosis, incomplete branchial arch syndromes, a branchial cleft cyst and a pseudocyst in connection with a vascular hamartoma anterior to the right ear of a 38-year-old woman is presented. A possible common pathogenesis of the vascular hamartoma and the incomplete branchial arch syndromes as well as that of the neurofibromatosis is suggested. The pseudocyst is interpreted as a branchial cleft cyst showing inflammatory changes due to a pharyngitis shortly before the preauricular tumor appeared.

Adult↗
PubMed1979

Chemotaxis or migration inhibition of rabbit peritoneal polymorphonuclear leukocytes caused by chemoattractants at various concentrations.

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 disciminate 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.

Animals↗
PubMed1979

The influence of specific antibodies and cellular immunity in the induction of tolerance of chemotactic activity caused by Bacteroides fragilis lipopolysaccharide.

Exudate aspirated from wound chambers implanted subcutaneously on rabbits at different time intervals after local lipopolysaccharide (LPS) injection, showed a peak of chemotactic mediator concentration in vitro about two hours before the peak of polymorphonuclear lekocytes accumulated in vivo was demonstrated. Injection of LPS locally into the wound chambers three days after the first injection of LPS showed a reduced number of PMNs accumulated in the exudate. Antibodies to the LPS preparation were demonstrated in the exudate and serum by indirect haemagglutination of sheep erythrocytes before the second LPS injection. This antibody titre increased up to two weeks after the first LPS injection, and was slightly higher in the serum than in the exudate. Also, a migration inhibition factor (MIF) activity was demonstrated in the exudates formed. This MIF activity of the exudates increased after the second LPS injection. The increased titre of specific antibody may indicate an accelerated clearance of LPS, and the MIF activity may indicate a reduced response of PMNs to chemotactic mediators. However, the involvement of other biological mechanisms contributing to the decreased response, cannot be excluded.

Animals↗
PubMed1979

[Autotransplantation of teeth: indication, technic and prognosis].

An account is given of the most important indications for tooth transplantation. The developmental stage of the tooth most suitable for transplantation and the special demands to the recipient site, are considered. Each main group of indication is illustrated with case reports. Finally, factors influencing the prognosis of the transplant are discussed.

Adolescent↗
PubMed1979

Endotoxins of anaerobic gram-negative rods.

Endotoxic lipopolysaccharides (LPS) isolated from Fusobacterium are similar to those of Salmonella with respect to chemical composition, O-antigenic specificity and endotoxic activity. Bacteroides LPS are highly atypical with respect to the chemical composition, and their endotoxic activity is low. O-Antigenic specificity is present. B. fragilis LPS is chemotactic for polymorphonuclear leukocytes in vitro and in vivo. The chemotactic activity is brought about by activation of the alternative complement pathway.

Animals↗
PubMed1978

Giant ranula causing mandibular prognathism.

This is a case report of a 20-year-old man with ranula, the size of an orange, in the floor of the mouth causing mandibular prognathism with fan-shaped mandibular teeth anterior to the premolars. The tumor was extirpated. The pathogenesis, differential diagnosis and treatment of ranulas are discussed.

Adult↗
PubMed1978

The importance of C5 and the role of the alternative complement pathway in leukocyte chemotaxis induced in vivo and in vitro by Bacteroides fragilis lipopolysaccharide.

Chambers implanted subcutaneously in C5 normal (C5 N) and C5 deficient (C5 D) mice were used to examine the migration of polymorphonuclear leukocytes (PMNs) into the wound chamber fluid in response to injected Bacteroides fragilis lipopolysaccharide (LPS). The difference in PMN migration was highly significant between the two mouse strains, the C5 D mice showing no initial, but a low, delayed migration. The results from the study indicated that chemotaxis plays a major role in the accumulation of PMNs in the acute inflammatory response. Intraperitoneal endotoxin stimulation also showed a significantly lower total number of leukocytes in the exudate from C5 D mice as well as a delayed migration of cells compared to C5 N mice. No leukotactic mediators were elaborated in C5 D serum or exudate upon incubation with LPS when tested in a modified Boyden chamber. However, endotoxin-induced wound chamber fluid in C5 D mice showed an increasing leukotactic activity at the same time as the acute inflammatory response subsided in C5 N mice. Incubation of B. fragilis LPS in C4 deficient (C4 D) guinea pig serum indicated that the LPS was able to activate complement components to generated split products chemotacic for rabbit PMNs via the alternative complement pathway.

Animals↗
PubMed1978

Rabbit polymorphonuclear leukocyte chemotactic factor generated in vivo by Bacteroides fragilis lipopolysaccharide. I. Isolation and physico-chemical characterization.

By chromatographic separation on Sephadex gels a peptide, termed the lipopolysaccharide-induced chemotactic factor (LPS-CF), has been isolated from inflammatory exudate. The exudate was obtained from Teflon chambers implanted subcutaneously in rabbits 3 h after LPS from Bacteroides fragilis ss. fragilis had been injected. Three chemotactic peaks were eluted by fractionation of the exudate on Sephadex G-200 columns; one major peak with molecular weight of approximately 16,000 and two minor peaks with molecular weights of approximately 68,000 and 7,000. Refiltration of the major peak on G-75 showed the same elution profile as that found on G-200 columns. By addition of 8 M urea to the elution fluid only the major and the low molecular weight peaks appeared. The molecular weight of the major chemotactic peak was calculated to 16,000 on Sephadex gels, and also using SDS-polyacrylamide gel electrophoresis and equilibrium centrifugation. The chemotactic factor was quite heat-stable and was also non-dialyzable, and freezing and thawing as well as storage at 4 degrees C for several weeks did not impede its activity. This chemotactic factor is probably identical to the cytotaxic fragment split off from C5 upon interaction with LPS.

Animals↗
PubMed1978

Rabbit polymorphonuclear leukocyte chemotactic factor generated in vivo by Bacteroides fragilis lipopolysaccharide. II. Antigenic and biologic properties.

Preparations of the polymorphonuclear leukocyte (PMN) chemotactic factor isolated from lipopolysaccharide (LPS)-induced inflammatory exudate in rabbits were immunogenic in guinea pigs. Complete fusion of the precipitation lines produced against anti-CF by LPS-CF (molecular weigth 16,000) and material eluted on Sephadex G-200 columns with molecular weights (MW) of 68,000, 16,000 and 7,000 was found. Also, the chemotactically active material with MW of 68,000 and 7,000 eluted on G-75 columns after fractionation of the fraction of MW 16,000 from the G-200 eluate was antigenically identical to LPS-CF in double diffusion in agar. Normal rabbit serum (NRS) incubated with LPS, LPS-induced wound chamber exudate and NRS alone gave lines of precipitation against the anti-LPS-CF sera identical to that of LPS-CF. The capacity of LPS-CF to attract PMNs was significantly higher than that of LPS, and a peak in the number of PMNs in the exudate of wound chambers implanted in rabbits was found 4 h after the local injection of LPS-CF. When injected intraperitoneally in C5 deficient mice, LPS-CF stimulated a PMN migration which was only slightly below that in C5 normal mice. Antisera to LPS-CF inhibited the chemotactic activity of LPS-CF as well as that of LPS-NRS when the supernatants were tested using the Boyden's technique. Also, preincubation of PMNs with LPS-CF suppressed the migration towards a chemotactic gradient of LPS-CF molecules of these PMNs.

Animals↗
PubMed1978

Induction of leukochemotaxis by protein A of Staphylococcus aureus.

The mechanism of the leukochemotactic activity of staphylococcal protein A (pA) has been studied by in vitro and in vivo experiments. Protein A alone or mixed with heat-inactivated serum induced no migration of polymorphonuclear leukocytes, demonstrating that pA is not a cytotaxin, but a cytotaxigen. Protein A, activating both pathways of the C system, induced chemotaxis in a C4 deficient serum, but not in a C5 deficient serum. This shows that the chemotactic mediator elaborated is a split product of C5, i.e. C5a. The chemotactic activity of pA observed in the presence of normal sera (in vitro) and in wound chambers (in vivo) was exclusively caused by C activation via reaction with Fc.

Animals↗
PubMed1978

Induction of leukochemotaxis by peptidoglycan of Staphylococcus aureus.

Leukochemotactic activity of staphylococcal peptidoglycan and isolated, specified fragments has been studied. The D-Ala-D-Ala group of the pentapeptide was found to be the major cytotaxigen, and C5a to be the dominant cytotaxin. A molecular weight of about 2,000 appeared to be a critical lower limit for inducing chemotactic response, the highest effect being observed with a fragment having a molecular weight of 3,000. The effect seems to depend on the kind of available antigenic determinants in the fragments and the proportion of specific antibodies in the complement source.

Animals↗
PubMed1977

Chemical composition, serological reactivity and endotoxicity of lipopolysaccharides extracted in different ways from Bacteroides fragilis, Bacteroides melaninogenicus and Bacteroides oralis.

Lipopolysaccharides (LPS) extracted from strains of Bacteroides fragilis, Bacteroides melaninogenicus and Bacteroides oralis with phenol-water, trichloroacetic acid, EDTA or liquid phenol-chloroform-petroleum ether (PCP) and isolated by ultracentrifugation, varied considerably in their quantitative chemical composition. Negligible yields of LPS were obtained by PCP-extraction. All preparations were more or less serologically active. All methods (except PCP) extracted the same O-antigenic determinants from B. fragilis. Endotoxic activity, as measured by primary skin inflammations in rabbits, was low but was present in all preparations. Proteins (and/or lipoproteins) co-precipitated with LPS in the ultracentrifuge.

Bacteroides↗
PubMed1977

Rabbit polymorphonuclear leukocyte migration in vitro in response to lipopolysaccharides from Bacteroides, Fusobacterium and Veillonella.

Puriified lipopolysaccharides (LPS) from strains of Bacteroides, Fusobacterium and Veillonella incubated with guinea pig serum, were tested for chemotatic activity against rabbit polymorphonuclear leukocytes (PMNs) in modified Boyden chambers. Comparisons were made to a Salmonella LPS (S. enteriditis S-795). Submicrogram amounts of LPS induced positive chemotaxis, and a typical dose-response relationship up to certain dose levels was observed. The difference in chemotactic activity between the Veillonella LPS and LPS-S-795 was not statistically significant. The Fusobacterium LPS showed either a non-significant or a highly significantly lower chemotatic capacity than LPS-S-795. The Bacteroides LPS were also clearly chemotactic, but considerable less when compared to the Salmonella LPS. When serum was not added, the LPS preparation showed no chemotactic activity.

Animals↗
PubMed1977

Rabbit polymorphonuclear leukocyte migration in vivo in response to lipopolysaccharides from Bacteroides, Fusobacterium and Veillonella.

Subcutaneously implanted chambers in rabbits were used for testing the migration of polymorphonuclear leukocytes in response to injected LPS isolated from strains of Bacteroides, Fusobacterium and Veillonella. A salmonella LPS was used as reference endotoxin. No differnece in chemotactic activity between the Veillonella LPS and LPS from Salmoneila was found. Fusobacterium LPS whoed insignificantly lower chemotactic capacity than the Salmonella LPS. The Bacteroides LPS were all significantly less chemotactic than the reference endotoxin. An insignificant correlation between the amount of exudate aspirated from the chambers 5 h after injection of the different LPS preparations and the number of leukocytes per microliter of exudate was found.

Animals↗
PubMed1977

Lethality for mice and chick embryos, pyrogenicity in rabbits and ability to gelate lysate from amoebocytes of Limulus polyphemus by lipopolysaccharides from Bacteroides, Fusobacterium and Veillonella.

Phenol-water extracted lipopolysaccharides (LPS) from Veillonella, Fusobacterium nucleatum, Bacteroides fragilis and Bacteroides melaninogenicus were lethal for mice and 11-days-old chick embryos, pyrogenic in rabbits, and gelated Limulus amoebocyte lysate. Mouse lethality was considerably enhanced by actinomycin-D. In all test systems the endotoxin activity of Veillonella and Fusocbacterium LPS was comparable to that of LPS from Salmonella enteritidis, which was included as a reference endotoxin. The endotoxicity of the Bacteroides LPS was very low. While nanograms of the Veillonella and Fusobacterium LPS killed the chick embryos and gelated the Limulus lysates, microgram amounts of the Bacteroides LPS were needed to give positive reaction in the same test systems. As much as 74 microgram of the most active B. fragilis LPS were required to give a typical biphasic fever response in rabbits. A significant correlation was found between all test results (r = 0.90-0.98, p less than 0.001).

Animals↗