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R M McKinney

Publications and source records attributed to R M McKinney.

53 records · Page 3Linked to original sources
PubMed1979

Soluble antigen extracts used as blocking agents to obtain specificity in serotyping of Streptococcus mutans.

Specific immunofluorescent (IF) conjugates were prepared for Streptococcus mutans serotypes d and g. Serotype specificity was obtained by blocking the cross-reacting antibodies with soluble antigen extracted from cells of the cross-reacting strains. Soluble antigen extracts are particularly useful in obtaining specificity with quantities of conjugates that are too small to be efficiently subjected to adsorption procedures. They also can be used advantageously to block traces of cross-reactivity that frequently remain with conjugates that have been subjected to conventional adsorption procedures. S. mutans isolates from dental plaque samples were identified as belonging to serotypes d or g on the basis of IF staining with conjugates that were made type-specific by blocking the cross-reacting antibodies with appropriate soluble antigen extracts.

Antigens, Bacterial↗
PubMed1979

Recognition of a new serogroup of Legionnaires disease bacterium.

A strain of the Legionnaires disease bacterium (LDB) that was isolated by Joseph E. McDade from a postmortem lung specimen of a patient with fatal atypical pneumonia at the Veterans Administration Hospital in Togus, Maine was serologically different from 16 other strains of LDB that had been isolated previously from patients in other geographic locations. The serological differences of the Togus isolate were shown in results of direct and indirect fluorescent antibody staining and of immunoelectrophoresis with soluble antigen extracts. Seroconversion for the Togus strain of LDB in acute- and convalescent-phase sera from a second patient with atypical pneumonia at the Veterans Administration Hospital in Togus indicated that this patient had been infected with an LDB that was serologically similar or identical to the Togus isolate. The Togus serogroup of LDB should be considered when performing serological tests for Legionnaires disease.

Antigens, Bacterial↗
PubMed1979

Double-staining procedure for the fluorescent treponemal antibody absorption (FTA-ABS) test.

The fluorescent treponemal antibody absorption (FTA-ABS) double-staining procedure was reproducible, comparable to the conventional test, and easy to read. We recommend the use of the FTA-ABS double-staining procedure for microscopes with incident illumination, the 100 x/1.30 oil achromatic objective and the 6.3 x ocular to obtain optimal fluorescence, and the KP560 as a barrier filter to exclude rhodamine emission when fluorescein fluorescence is read. With this system, errors related to poor focusing or failure to visualise treponemes on all smears should be eliminated.

Fluoresceins↗
PubMed1979

Four serogroups of Legionnaires' disease bacteria defined by direct immunofluorescence.

Thirty-five strains of Legionnaires' disease bacteria were shown to belong in four distinct serologic groups on the basis of findings obtained with direct fluorescent antibody testing. Thirty of the strains were placed in group 1, three in group 2, one in group 3, and one in group 4. Immunoelectrophoretic studies showed both unique and common antigens among the representative strains of the four serogroups.

Antigens, Bacterial↗
PubMed1979

A newly identified bacterium phenotypically resembling, but genetically distinct from, Legionella pneumophila: an isolate in a case of pneumonia.

A bacterium with growth characteristics similar to, but genetically distinct from, either Legionella pneumophila or WIGA (a "rickettsia-like agent") was obtained from a postmortem lung specimen of a patient with fatal atypical pneumonia at the M. D. Anderson Hospital and Tumor Institute in Houston, Texas. This bacterium and WIGA have essentially the same cellular fatty acid composition, which is distinct from that of L. pneumophila. Deoxyribonucleic acid-reletadness studies show that the isolate from Texas is only about 10% related to both L. pneumophila and WIGA and there fore may represent a new species. This new bacterium should be considered in selecting laboratory procedures in the diagnosis of atypical pneumonia.

Bacteria↗
PubMed1978

Improved immunoadsorption procedure with anion-exchange bacterial cell columns.

Bacterial cell columns for immunoadsorption were prepared with Streptococcus cells and triethylaminoethyl cellulose (Cellex-T) matrix material as a model system. Good column flow properties and satisfactory retention of the cells were obtained with ratios as high as 2 ml of packed cells/3 g dry weight of cellulose. Anion-exchange fractionation of whole serum by the Cellex-T was prevented by using 0.25 M NaCl in the developing buffer. Antibodies were adsorbed directly from whole serum and recovered in high yield by desorption at pH 2.3. Pre-exposing bacterial cells to formalin and washing them with acetone was necessary to ensure that they remained on the columns. One strain of Streptococcus salivarius (SS 908) was satisfactorily retained on a column only after cells were labeled with fluorescein isothiocyanate and washed with acetone. The means by which Cellex-T retains bacterial cells appears to be a combination of electronic attraction and physical entrapment.

Chromatography, Ion Exchange↗
PubMed1976

Diethylaminoethyl-cellulose-bacterial cell immunoadsorbent columns: preparation of serotype-specific globulin and immunofluorescent conjugates for Streptococcus mutans serotypes a and d.

Diethylaminoethyl (DEAE)-cellulose was used as a support material for preparing bacterial cell columns. Pretreatment of the bacterial cells with formalin was essential in obtaining satisfactory adherence of the cells to DEAE-cellulose. Cross-reacting antibodies were removed from antibody preparations against strains of Streptococcus mutans serotypes a and d by adsorption on appropriate bacterial cell columns. S. mutans serotype d was further divided into two subtypes on the basis of immunofluorescent staining with conjugates of immunospecifically adsorbed immunoglobulin G. The DEAE-cellulose-bacterial cell columns were regenerated after use by desorbing the cross-reacting antibodies with low-pH buffer and were used repeatedly over and 18-month period with no detectable loss in effectiveness.

Adsorption↗
PubMed1975

An approach to quantitation in rhodamine isothiocyanate labeling.

A survey of commercially available TMRI and RBI products revealed that many are of unsatisfactory quality. Optimum dye/IgG ratios were obtained in conjugates with TMRI of about 65% purity by labeling them with reaction mixture ratios of 10 and 20 mug dye/mg IgG. Optimum labeling with RBI of comparable purity required reaction mixture ratios of at least 20 mug dye/mg IgG. Although specific storage stability studies of TMRI or RBI products were not performed, one TMRI product underwent appreciable degradation during a 2-year period of storage in a desiccator over Drierite. The importance of evaluating the protein labeling capacity of TMRI or RBI products before making immune conjugate preparations is evident.

Animals↗
PubMed1973

Occurrence of branched-cahin hydroxy fatty acids in Pseudomonas maltophilia.

Three branched-chain hydroxy acids not previously reported in other bacteria were found in extracts from saponified whole cells of Pseudomonas maltophilia. On the basis of evidence from mass spectrometry, infrared spectroscopy, and gas chromatographic procedures, they were identified as 2-hydroxy-9-methyldecanoic acid, 3-hydroxy-9-methyldecanoic acid, and 3-hydroxy-11-methyldodecanoic acid. These acids appeared to be tightly bound to other cellular components since they were not extracted from lyophilized cells with a chloroform-methanol (3:1) mixture.

Bromine↗