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R S Martin

Publications and source records attributed to R S Martin.

At least 73 records · Page 4Linked to original sources
PubMed1984

A synthetic based medium for the isolation of Listeria monocytogenes.

We have compared two media (Tryptone Soya Nalidixic Acid Agar and Tryptone Soya Gum Base Nalidixic Acid Medium) for the isolation of L. monocytogenes from pathological and environmental specimens. These media were used in conjunction with Henry's Oblique Light System. We found that the gum based medium gave the better results. The medium is uniformly transparent, partially suppressive to unwanted organisms and allows colonies of Listeria to be readily identified.

Culture Media↗
PubMed1984

Physicochemical characterization of the urinary lipid from humans with nephrotic syndrome.

The aim of this study was to investigate the nature of urinary lipid in humans with nephrotic syndrome. Fresh urine specimens were fractionated by centrifugation into a lower cellular fraction and an upper noncellular fraction. Of the 11 urine specimens examined, six cellular fractions contained cells (oval fat bodies) that were laden with anisotropic (birefringent) droplets when viewed by polarizing microscopy. The mean total cholesterol excretions for the five urine specimens without anisotropic droplets and the six urine specimens with anisotropic droplets were 8.7 mg/L and 35.5 mg/L, respectively. The cellular fractions of the six urine specimens with anisotropic droplets are enriched in cholesterol esters relative to whole urine. Upon heating, the anisotropic droplets underwent phase transitions characteristic of cholesterol esters, as observed by polarizing microscopy. The mean cholesteric to isotropic phase transition temperature of the anisotropic droplets was 41.3 degrees C. These data indicate that the anisotropic droplets of the oval fat bodies were composed of cholesterol esters acylated largely with monounsaturated fatty acids consistent with cellular origin. The noncellular fractions were subjected to ultracentrifugation (48,000 X g for 2 hours) and then separated into supernate and infranate fractions. The supernate fractions contained minor amounts of lipid, except in two cases of massive lipiduria. In these two cases, the supernate fractions contained many individual anisotropic droplets with lipid composition nearly identical to their cellular fractions. The dispersed lipid of the infranate fractions were invisible by microscope. Nine of the 11 infranate fractions revealed an alpha migrating lipid band by agarose gel electrophoresis. For urine specimens with anisotropic droplets, the infranate fractions contained cholesterol ester fatty acids that were less saturated (as measured by gas-liquid chromatography) than the cellular fractions. Thus, the cholesterol esters of the infranate fractions were derived from a different source (probably high-density lipoproteins) than the cholesterol esters of the cellular fractions.

Adolescent↗
PubMed1981

Coexistence of a primary immunodeficiency disorder and Hodgkin's disease: evidence against a B-lymphocyte origin for the Reed-Sternberg cell.

A 44-year-old woman with a life-long history of recurrent sinopulmonary infections developed Hodgkin's disease with characteristic Reed-Sternberg cells in a biopsy specimen of a mediastinal lymph node. Hypogammaglobulinemia was documented on several serum determinations and plasma cells were absent from biopsy specimens of the lymph node and bone marrow. Immunochemical studies failed to demonstrate any B lymphocytes bearing surface immunoglobulin or Fc-receptors for IgG in the peripheral blood. Pokeweed mitogen stimulation of the patient's peripheral blood lymphocytes in vitro resulted in the development of virtually no plasma cells. Peripheral blood T-lymphocyte number and function were defective initially. Following chemotherapy and radiotherapy, peripheral blood E-rossette-forming cells returned to normal, but T-cell function remained defective and B lymphocytes remained undetectable. These findings are compatible with the presence of two separate immune disorders: a primary hypogammaglobulinemia and Hodgkin's disease. The absence of lymphocytes bearing surface Ig or Fc-receptors for IgG in this patient adds further support against a B-lymphocyte origin for the Reed-Sternberg cell.

Adult↗
PubMed1981

Causes of atypical pneumonia: results of a 1-year prospective study.

In a protocol study of cases of atypical pneumonia over a 1-year period an etiologic agent was established in 16 cases: Legionella pneumophila in 8, Coxiella burnetii in 3, Chlamydia trachomatis in 2, Mycoplasma pneumoniae in 1, para-influenza 3 virus in 1 and cytomegalovirus in 1. In the remaining 11 cases no agent was identified; the illnesses in these cases tended to be less severe. The pneumonia took much longer to resolve in the patients with Legionnaires' disease than in all the other patients (mean interval from onset of symptoms to clearing of the chest roentgenogram: 69 days v. an average of 16 days). However, the length of stay in hospital was similar for the three groups: those with Legionnaires' disease, those with atypical pneumonia of unknown cause and those with atypical pneumonia of various other established causes. L. pneumophila infection may explain a proportion of atypical pneumonias that previously could not be diagnosed, although in this series the cause of 41% of the pneumonias remained unexplained.

Chlamydia Infections↗
PubMed1978

Electron-capture GLC determination of ibuprofen in serum.

To evaluate drug-protein binding, a sensitive method for the determination of ibuprofen in submilliliter amounts of serum was required. A specific and highly sensitive procedure, based on benzene extraction of the acidified specimen. TLC of the benzene extract residue, fomation of the pentafluorobenzyl esters of the materials eluted from the thin-layer chromatogram, and quantification of the pentafluorobenzyl esters by GLC, was developed. Utilizing electron-capture detection, the method is sensitive to 0.1 microgram of ibuprofen/0.1 ml of serum. Statistical analyses indicated an average recovery of 97.7% with a standard deviation of +/- 7.3%. Mass spectrometric analysis, in conjunction with GLC, confirmed the specificity of the method for the intact drug. The procedure was applied successfully to drug absorption and drug-protein binding studies in humans.

Blood Proteins↗
PubMed1978

Assessment of expectorated sputum for bacteriological analysis based on polymorphs and squamous epithelial cells: six-month study.

Samples of sputum were examined microscopically to determine their suitability for routine culture. When the number of squamous epithelial cells per field was less than 10, the number of bacterial species generally fell within the range of one to four. Squamous epithelial cells were not always a true indication because some unmarked transtracheal specimens showing more than 10 squamous epithelial cells also gave a range of isolation falling between one and four. When the presence of 25 or more polymorphs was used as the parameter, the number of bacterial isolates generally fell within the range of one to three, but this resulted in positive overbiasing with consequent rejection of valid specimens. Later it was found that when a differential system using both polymorphonuclear cells and squamous epithelial cells was applied, a significant number of specimens could be salvaged which would otherwise have been discarded.

Epithelial Cells↗
PubMed1975

Comparison of four culture media for the isolation of Mycobacterium tuberculosis: a 2-year study.

Four media, Lowenstein-Jensen, Middlebrook, Petragnani, and ribonucleic acid, were tested for comparative ability to detect Mycobacterium tuberculosis. Specimens used included sputum, urine, tissue, and gastric washings. Three types of comparison were used: (i) comparison derived from randomized specimens; (ii) comparison of cultures from newly diagnosed cases that had received no prior therapy; and (iii) comparison of cultures from specimens whose initial direct smears were negative. Overall, ribonucleic acid medium performed best, but the differences among the four media were small.

Cerebrospinal Fluid↗