The invasions of tissues by pathogenic microorganisms is followed by a sequence of events which culminate in phagocytosis and the intracellular killing of the ingested agents, by “professional” phagocytes [19]. It is also expected that the rich arsenal of hydrolases present in neutrophils and macrophages, including the muralytic enzyme lysozyme is adequate to degrade the complex architecture of the bacterial cells. Surprisingly, however, most pathogenic bacteria are extremely resistant to lysozyme action [14,21] and the fate of phagocytosed bacteria in vivo is not fully known [7,8,16,23]. The sequelae of the lack of bacterial degradation by leukocytes may be the “storage” of peptidoglycan-polysaccharide or peptidoglycan-lipopolysaccharide complexes within macrophages leading to the generation of granulomas and to the initiation of prolonged immune responses. This is pivotal to the initiation of immunopathological reactions [7, 8, 16, 23]. We have recently proposed [10, 11, 12, 13, 15, 29] that the biodegradation of certain microorganisms can be mediated through the activation, by cationic agents and phospholipases, of the bacterial own autolytic wall enzymes (suicidal phenomenon) which leads to the breakdown of the rigid cell walls. On the other hand, a variety of sulfonated anionic polyelectrolytes [11–13, 15] likely to be present in inflamed issues, may inhibit the biodegradation of the walls by the autolytic enzymes.
High concentrations of phosphate, oxalate, and calcium ions in urine may cause formation of mineral deposits, i.e., urolithiasis. This is prevented in healthy individuals by substances present in trace quantities. However, there is no recognizable difference between normals and stone formers in urinary substance content. The enzymes glutamic oxaloacetic transaminase and glutamic pyruvic transaminase produce glutamic acid which retards calcium oxalate crystallization. The combined transaminase activity in 70 stone former urine samples was 12.2 +/- 4.1 IU and 31.9 +/- 10.7 IU for 47 normal controls. Incubation of stone former urine with glutamic oxaloacetic transaminase improved overall inhibitory potential, raised glutamic acid levels, and decreased aspartic acid concentrations. Correlation was established between the success of therapeutic treatment and the improvement of enzyme activity. The relative content of glutamic acid is low stone former urines and high in active inhibitory fractions of urinary materials. It is suggested that part of the mechanisms of prevention of stone formation is subjected to biological control.[on SciFinder (R)]
Bromination, chlorination and hydroxylation of the double bond in polyethylene glycol oleates and oleyl ethers and polyglycerol oleates were carried out. The products had higher sp. gr. and therefore can be used as weighting agents. Surface properties and the ability to emulsify water and oils did not change significantly. Phys. (sp. gr., viscosity, and refractive index) and surface properties (such as redn. of surface tension of water, crit. micelle concn. (CMC), area per mol. at the liq./air interface, efficiency and effectiveness were measured and compared to the corresponding unsatd. surfactants. The incorporated dibromo, dichloro, or dihydroxy groups diminish some of the surface properties of the surfactant, e.g. higher surface tension, higher CMC value, higher area per mol., and lower efficiency and effectiveness in comparison to the related unsatd. surfactants. This study confirmed early findings suggesting that oleyl ethoxylated surfactants behaved abnormally when compared to straight chain ethoxylated alcs. or acids or polyglycerol esters and that any derivatization in the hydrophobic chain would significantly alter surface properties. [on SciFinder(R)]
Tissue samples obtained from human gingiva with soft tissue calcification were processed for light and transmission electron microscopy. The stroma in these specimens revealed numerous foci of calcification in a matrix that consisted of closely packed branching microfibrils, 12 nm in diameter and a maximum of 2.5 micron in length. Calcospherites, 0.25-1.11 micron in diameter, were present within the matrix. They were constructed of needle-like units shown by high resolution electron microscopy and energy dispersive X-ray microanalysis to be apatite. Larger calcified masses were composed of calcospherites which were fused together. Matrix vesicles or other forms of membraneous material could not be found. The relationship between the mineral and non-collagenous microfibrils may suggest a role for the latter in the onset of calcification in this ectopic site.
Human blood leukocytes generate intense luminol-dependent chemiluminescence (LDCL) following stimulation by streptococci and by Gram negative rods which had been preopsonized by cationic polyelectrolytes (histone, poly L-arginine-PARG, poly L-histidine-PHSTD). Streptococci but not Gram negative rods or hyaluronic acid-rich streptococci (group C) also induced intense LDCL following opsonization with the anionic polyelectrolytes-dextran sulfate or polyanethole sulfonate (liquoid) suggesting that the outer surfaces of different bacteria bound anionic polyelectrolytes to different extents. Both normal and immune serum, synovial fluids and pooled human saliva inhibited the LDCL responses induced by streptococci preopsonized with poly cations. On the other hand, bacteria which had been first preopsonized by the various body fluids and then subjected to a second opsonization by cationic ligands ("sandwiches"), induced a very intense LDCL response in leukocytes. Streptococci which had been preopsonized by PARG, histone or by PHSTD also triggered superoxide generation by blood leukocytes, which was markedly enhanced by a series of cytochalasins. PHSTD alone induced the formation of very large amounts of superoxide. Paradoxically, the same concentrations of cytochalasins B or C which markedly boosted the generation of superoxide following stimulation of leukocytes with soluble or particulate ligands, had a strong inhibitory effect on the generation of LDCL. On the other hand cycochalasins failed to inhibit LDCL which had been induced by phorbol myristate acetate (PMA). Peritoneal macrophages which had been harvested from C. parvum-stimulated mice, generated more LDCL and superoxide following stimulation by PARG than macrophages obtained from proteose peptone-stimulated mice. Macrophages which had been activated either by proteose peptone or by C. parvum and cultivated for 2 hours on teflon surfaces, generated much more LDCL than macrophages which had been cultivated for 24 hours on teflon surfaces. Both cationic and anionic polyelectrolytes mimic the effects of antibodies as activators of the oxygen burst in blood leukocytes and in macrophages. Such polyelectrolytes can serve as models to further study leukocyte-bacteria interactions in infectious and inflammatory sites.
The effect of emulsifier type on the prepn. and stability of multiple emulsions was studied. The effect on the yield of prepn. and stability with regard to the hydrophile-lipophile balance of the 2nd emulsifier was different for each emulsifier. The best stabilities of the multiple emulsions were obtained when there was a similarity between the hydrophobic part of the emulsifier and the oil phase. [on SciFinder(R)]
