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Notes: Periodontal inflammation was induced in rats by injection of bacterial sonic extracts isolated from Gram negative gingival pathogens: Capnocytophaga sputigena and Actinobacillus actinomycetemcomitans. The inflammatory reaction was characterized by a massive leukocytic infiltration, granulation tissue, and abscess formation. In addition, bone resorption and primary bone formation via extracellular matrix vesicles were observed. Matrix vesicle fractions obtained from the alveolar bone of rats with inflammation revealed an increase of acid phosphatase activity as compared to controls. Studies of alkaline phosphatase activity in the vesicular fractions revealed no differences between experimental and control groups. The possible role of bacterial products in alveolar bone remodeling in the light of the enzymatic alterations and morphological observations is discussed.

Notes: The effect of a slow-releasing dosage (SRD) coating of chlorhexidine on the salivary levels of Streptococcus mutans and on plaque index scores in patients with removable partial dentures (RPD) was tested. The SRD proved to be effective in maintaining a low level of S. mutans counts after mechanical cleaning, as compared to a baseline established during the control period. Plaque index scores were lower following the treatment and correlated with the microbiological results. Our findings indicate that a single application of sustained-release chlorhexidine to removable partial dentures effectively maintains S. mutans levels as well as reducing the plaque score for a minimum period of 1 week.

Notes: The presence of lipoproteins and lipooligosaccharides in Treponema denticola, an oral spirochaete associated with periodontal diseases, was investigated. T. denticola ATCC 35404 and the clinical isolate GM-1 were metabolically labeled with [3H]-cis-9-octadecenoic acid and extracted with the non-ionic detergent Triton X-114. The extract was phase separated, precipitated with acetone and delipidated to remove non-covalently bound lipid (dLPP). In T. denticola ATCC 35404, sodium dodecyl sulfate polyacrylamide electrophoretic separation followed by autoradiography showed [3H]-cis-9-octadecenoic acid incorporation in bands with apparent molecular masses of 14, 20, 26, 31, 38, 72 and 85 kDa and a broad band running from 113 kDa to the top of the gel. This last band resolved into a 53 kDa [3H]-cis-9-octadecenoic acid band upon heating for 10 min, at 100oC. The structural relationship of the outer sheath major oligomeric polypeptide of strain ATCC 35404 and the 53 kDa protein was demonstrated immunologically. Antibodies against the 113 kDa component of the oligomer cross-reacted with the 53 kDa protein. Proteinase K degraded the [3H]-cis-9-octadecenoic acid bands with the exception of the 14 kDa. The 14 kDa was also the major [3H]-fatty acid labeled compound found in the water phase following phenol-water extraction of whole T. denticola ATCC 35404 cells. This compound was purified from the water phase by gel filtration followed by hydrophobic chromatography. Chemical analysis showed that hexadecanoic acid was the predominant fatty acid bound to T. denticola lipoproteins. In the GM-1 strain [3H]-cis-9-octadecenoic acid incorporation was observed in the 116 kDa and 14 kDa bands. dLPP from strain ATCC 35404 caused an enhanced (0.8–8 μg/ml) luminol dependent chemiluminiscence (LDCL) effect in human polymorphonuclear neutrophils (PMN) which could be related to protein concentration. The addition of dLPP to PMN together with FMLP at submaximal concentration (1 μM) resulted in a synergistic activation of LDCL. At 21 μg/ml, dLPP also induced lysozyme release by the PMN at approximately 30% of the release induced by the chemotactic peptide at 1 μM. In addition, dLPP (21 μg/ml) increased additively the release of lysozyme caused by 1 μM FMLP. The release of β-glucuronidase was not affected. The modulation of neutrophil activity was abolished by preincubation of dLPP with proteinase K. The purified 14 kDa had no effect on either LDCL or exocytosis of lysosomal enzymes of PMN. These data strongly suggest that T. denticola possesses several lipoproteins including outer sheath major oligomeric polypeptides (113-234 kDa) and a lipooligosaccharide of molecular mass of 14 kDa. In addition, an enriched lipoprotein fraction from this oral spirochaete modulates oxygen dependent and independent mechanisms for controlling microorganisms by human PMN.

Notes: Abstract Acid hydrolases from extracts of human blood leucocytes lyseStaph. aureus, Staph.albus andStrep. faecalis in vitro. The leucocyte enzymes can be substituted by a lytic mixture which contains crude trypsin, lysolecithin, phospholipase C and lysozyme, which lyse other bacterial species, e.g.E. coli and Listeria which are resistant to leucocyte enzymes. Bacteriolysis by the lytic agents is strongly inhibited by the anionic polyelectrolytes, heparin, chondroitin sulphate, DNA, dextran sulphate and other sulphated mucopolysaccharides, by the cationic materials, histone, protamine sulphate, leucocyte cationic proteins and polylysine. Other strong inhibitors are trypan blue and congo red, the phospholipids phosphatidyl serine and ethanolamine, gold thiomalate, extracts of coffee and tea and the anti-inflammatory agents, ultracorten-H, and ultracortenol. Bacteriolysis is also strongly inhibited by normal human serum and by synovial fluids from patients with a variety of joint diseases. The inhibitors in these body fluids are associated with the globulin fractions. Since mixtures of anionic and cationic polyelectrolytes, at equimolar concentrations, failed to inhibit bacteriolysis by leucocyte enzymes, it is postulated that a delicate balance between positively and negatively charged inhibitors control the degradation of cell wall components of bacteria in inflamed areas. Such bacterial components, induce ‘storage type’ granulomas. The possible role played by polyelectrolytes in the control of the inflammatory process induced by leucocyte hydrolases will be discussed.

Notes: Abstract This paper presents a novel reconfigurable modular system for the fixturing of thin-walled, flexible objects subject to a discrete number of point forces. The paper comprises two parts: description of the conceptual design of our new reconfigurable fixture, and a brief review of our earlier work on the optimal reconfiguration of the object-support locations. During the mechanical design phase of the fixture, a conscientious effort was made to develop a robust and low-cost system. The primary components of the fixture are: a baseplate, support locators and clamps. A novel tiltable support-surface design, through which the height of the surface can be maintained constant, is used for the locators and the clamps. A fixture reconfiguration method is proposed to place these locators, underneath the object, as an optimal support wall. Potential surface deflections due to external forces are minimised during the optimisation process.

Notes: Abstract Blast transformation of human peripheral blood lymphocytes by PHA is shown to be modulated by lipoteichoic acid (LTA) ofStreptococcus mutans, by a cell-sensitizing factor ofActinomyces viscosus, as well as by a frozen and thawed extract of human leukocytes (LE). While small amounts of LE (5–50Μg/106 cells) significantly enhanced PHA-induced transformation, higher amounts showed a lesser effect on the blastogenic response. Both LTA and theA. viscosus extract did not cause any lymphocyte blastogenic effect when used alone. On the other hand LTA had an inhibitory effect and theA. viscosus extract had an enhancing effect when lymphocytes were pretreated by these agents and then exposed to PHA.

Notes: Abstract Normal sera and plasma, derived from humans, calves, rats, rabbits, horses, human synovial fluids, inflammatory exudates, and leukocyte extracts, when sufficiently diluted are highly bacteriolytic forStaph. aureus, Strep, faecalis, B. subtilis and to a variety of gram-negative rods. On the other hand, concentrated serum or the other body fluids are usually not bacteriolytic for these bacterial species. While the lysis ofStaph. aureus andB. subtilis by diluted serum is not lysozyme dependent, lysis ofStrep. faecalis is absolutely dependent on the concentration of lysozyme. The lytic factor in human serum is present in Cohn's fractions III, IV, and V. It is nondialyzable, resistant to heating for 75° C for 20 min, and acts optimally at pH 5.0. Like leukocyte extracts, synovial fluids, and inflammatory exudates, it lyses only young staphylococci. The inability of concentrated serum to lyseStaph. aureus andStrep, faecalis is due to the presence in the gamma globulin fraction of a potent inhibitor, which can be partly removed by dilution or by adsorption upon the homologous bacteria. Lysis of the bacteria is also strongly inhibited by Cohn's fraction II (gamma globulin) by high-molecular-weight DNA, heparin, liquoid, and histone. The possible role played by serum globulin in the protection of bacteria against degradation by leukocyte is discussed.

Notes: Abstract We investigated the bacteriolytic activity of gingival crevicular fluid (CF) on14C-labeledStreptococcus faecalis, Streptococcus mutans, Staphylococcus aureus, and on whole dental plaque. CF was collected from 100 healthy donors pooled and centrifuged at 200g. CF supernate and a frozen and thawed extract of the pellet were interacted with the different bacterial strains, whileStreptococcus faecalis andStaphylococcus aureus released 60% and 75% of the radioactive label, only 38% of it was solubilized fromStreptococcus mutans, following their incubation with the CF supernate. The findings agreed with results obtained by interacting bacteria with a frozen and thawed lysate of human peripheral blood leukocytes. On the other hand, extracts from frozen and thawed CF pellet were inactive. Further, lipoteichoic acid and lipopolysaccharide were released by CF from Gram-positive and Gram-negative bacteria, respectively. The role of bateriolytic factors, present in CF, as a result of the interaction between microorganisms and leukocytes at inflammatory sites is discussed.

Notes: Abstract The ability of oral polymorphonuclear leukocytes (PMNs) to phagocytoseCandida albicans cells and bindSalmonella typhi via complement receptors was investigated. A significantly higher percent of oral PMNs could phagocytose and bind via complement receptors as compared to peripheral blood PMNs. While treatment of peripheral blood PMNs with the donor's saliva caused an increase in the number of complement-receptor bearing cells, as well as a partial increase in phagocytosis, PMNs treated with gingival crevicular fluid (CF) showed a decrease both in phagocytosis and binding. The complexity of environmental conditions and factors, and its role in PMN functions in inflammatory sites is discussed.

Notes: Abstract Crude extracts of human blood leukocytes were employed as a source of bactericidal and bacteriolytic agents againstStaphylococcus aureus. While the bactericidal action of the extracts was a very rapid process, bacteriolysis is a very slow process. Both the killing and the lysis of staphylococci depended on the age of the culture, maximal effects being obtained only with young cells. The killing of staphylococci by the extracts was absolutely dependent on the density of bacteria employed. On the other hand, bacteriolysis was only very slightly affected when large numbers of bacteria were employed. Both the bactericidal and bacteriolytic reactions were optimal at pH 5.0. Under similar conditions, extracts of pus and the “cocktail” of enzymes were both bactericidal and bacteriolytic, but extracts of small intestine and of platelets were not significantly bactericidal. Experiments, designed to differentiate between the bactericidal and bacteriolytic properties of the extracts showed that both properties were preserved following heating in acid solutions but were completely destroyed following heating in alkaline solutions. The bactericidal factor in the lysates could be readily adsorbed on large numbers of viableStaph. aureus andE. coli, but the bacteriolytic properties of the extracts could not be removed by adsorption. The bactericidal effect of the extracts could not be inhibited by a variety of anionic polyelectrolytes, but all these agents strongly inhibited the bacteriolytic effect. Moreover, several of the anionic substances potentiated the bactericidal effects mediated by the extracts. Potentiation of these effects was also caused by protamine sulfate and by polylysine, which were highly bactericidal by themselves. The only substance that was found to abolish the bactericidal effects of the extracts is ultracorten H. Historie and polylysine (which are highly bactericidal) lost their effects when mixed with certain concentrations of heparin or polyglutamic acid, which by themselves are not bactericidal, indicating that an appropriate balance between cationic and anionic substances may determine the bactericidal effects of cationic substances. Since the bactericidal properties of the lysates could not be abolished by any of the anionic macromolecular substances employed; it is suggested that the bactericidal agents present in crude whole lysates of leukocytes comprise a complex mixture of agents, some of which are not identical with cationic substances. Thus, the data suggest that the employment of highly purified cationic proteins of leukocytes and tissues to study bactericidal models may not reflect the actual conditions that prevail in inflammatory exudates. The possible role played by cationic and anionic polyelectrolytes in the control of bacterial survival and lysis in inflammatory exudates is discussed.