ABSTRACT
The purpose of the present investigation was to determine the effectiveness of the Myo in reducing plaque and gingivitis development in orthodontic patients using a single-blind, cross-over design. Thirty subjects were randomly assigned to experimental and control groups. All subjects continued their customary oral hygiene procedures. In addition, the experimental group was instructed to chew on the Myo for four minutes, twice each day. Plaque Index and Gingivitis Index were assessed each time the subjects attended their scheduled orthodontic appointment. The patients failed to demonstrate any significant reduction in plaque and gingivitis development when the Myo was introduced as an additional oral hygiene measure. Some soft tissue injuries were found.
Subject(s)
Dental Plaque/prevention & control , Gingivitis/prevention & control , Oral Hygiene/instrumentation , Orthodontic Appliances , Adolescent , Cross-Over Studies , Dental Plaque Index , Equipment Design , Female , Humans , Male , Observer Variation , Periodontal Index , Reproducibility of Results , Single-Blind Method , Time FactorsABSTRACT
Several 5,5'-substituted-2,4-imidazolidinedithiones, synthesized from aldehydes or ketones, have been purified by HPLC using poly(styrene-divinylbenzene) packings. Purified 5,5'-substituted-2,4-imidazolidinedithiones have been identified in column effluent by UV absorbance and corroborated by mass spectrometry. Several silica-based, polymeric, and poly(styrene-divinylbenzene)-based packings were evaluated as matrices for resolution of a mixture of purified 5,5'-substituted-2,4-imidazolidinedithiones.
Subject(s)
Chromatography, High Pressure Liquid/methods , Thiohydantoins/isolation & purification , Mass Spectrometry , Spectrophotometry, UltravioletABSTRACT
Two chemical assays have been developed for identifying and quantifying peptides which either could be biologically active by virtue of their alpha-carboxamidation or could be substrates for peptidylglycine alpha-amidating mono-oxygenase. The first assay is specific for the alpha-carboxamide of peptides. Using bis[trifluoroacetoxy]iodobenzene, the alpha-carboxamide was converted via a Hoffman reaction into a primary amine, which was then quantified by ninhydrin. The second assay is specific for glycine at the carboxy-terminus of a peptide. Glycine at the carboxy-terminus was derivatized to form 2-thiohydantoin, which was then separated and quantified by reverse phase HPLC. These assays were used to detect peptides in HPLC-separated extracts of bovine hypothalamus, bovine anterior lobe pituitary and porcine heart which may be of biological interest.
Subject(s)
Amides/analysis , Glycine/analysis , Hypothalamus/chemistry , Myocardium/chemistry , Peptides/analysis , Pituitary Gland, Anterior/chemistry , Acetylation , Amino Acid Sequence , Animals , Asparagine/metabolism , Cattle , Chromatography, High Pressure Liquid , Glutamine/metabolism , Mass Spectrometry , Molecular Sequence Data , Oxidation-Reduction , Swine , ThiohydantoinsABSTRACT
The immunoglobulin M antibody response to the lipoteichoic acid (LTA) of Staphylococcus aureus ATCC 6538P was examined by a procedure in which erythrocytes sensitized with periodate-activated LTA were used for the detection of immunoglobulin M-producing plaque-forming cells LTA-specific plaque-forming cells were first detected 2 days after immunization with heat-killed bacterial cells, and maximal numbers of plaque-forming cells, mostly of the immunoglobulin M class rather than the immunoblogulin G or immunoglobulin A class, were attained by day 4; specificity for LTA was affirmed by plaque inhibition tests. No plaque-forming cells were found in mice given isolated LTA over a 10,000-fold range of immunizing doses. Mice pretreated with a carrier known to activate thymus-derived helper lymphocytes produced a plaque-forming cell response to LTA only when immunized with LTA bound to the same carrier. This suggests that carrier-specific thymus-derived cells are needed to initiate an antibody response to poorly immunogenic LTA. Since an antibody response can be elicited in mice given heat-killed cells, other cell wall and/or cell membrane constituents may play an important role as immunologically active carriers for this antigen.
Subject(s)
Antibodies, Bacterial/biosynthesis , Immunoglobulin M/biosynthesis , Lipopolysaccharides , Phosphatidic Acids/immunology , Staphylococcus aureus/immunology , Teichoic Acids/immunology , Animals , Antibody Specificity , Antibody-Producing Cells/immunology , Female , Immunization , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , T-Lymphocytes/immunologyABSTRACT
The periodate oxidation and chromium chloride coupling methods were compared for their ability to sensitize indicator erythrocytes with staphylococcal lipoteichoic acid (LTA) for the detection of specific antibody. Erythrocytes, sensitized with periodiate-activated lipoteichoic acid, were found to be superior for use in both passive immune hemagglutination and hemolysis tests as well as in the technique of localized hemolysis-in-gel for the detection of specific antibody-producing cells against LTA.
