Relationship of some biochemical characteristics of Staphylococcus aureus to enterotoxin production

A total of 151 enterotoxigenic and 98 non-enterotoxigenic strains of Staphylococcus aureus were examined for production of coagulase, phosphatase, deoxyribonuclease, haemolytic activity, glucose and mannitol fermentation, typical growth on Baird-Parker medium, pigment production and growth under anaerobic conditions. Enterotoxigenic strains showed a higher tendency to demonstrate haemolytic activity, but none of the other biochemical properties could be correlated with the ability of the staphylococci to produce enterotoxins. It appears that other ancillary tests must be developed to be useful in the differentiation of enterotoxigenic and non-enterotoxigenic staphylococci.

Measurement of plasma fructosamine evaluated for monitoring diabetes

The mean fructosamine concentration in plasma of diabetics (n = 200) differed significantly (p less than 0.001) from those of a hospitalized nondiabetic population (n = 163)--the latter mean being essentially the same for ambulatory subjects (n = 145), expectant mothers (n = 58), and patients with renal failure (n = 31), regardless of sex. In the diabetic group, values for plasma fructosamine correlated with those for glycated hemoglobin (r = 0.767, p less than 0.01) and glycated protein (r = 0.817, p less than 0.01). Values for plasma fructosamine were stable from day to day in patients with controlled blood glucose, but fluctuated in certain patients receiving only parenteral nutrition, even when their concentrations of glucose were normal and stable. We conclude that measurement of plasma fructosamine is suitable for assessing intermediate-term control of blood glucose when the turnover of plasma proteins is normal.

Measurement of plasma fructosamine evaluated for monitoring diabetes

The mean fructosamine concentration in plasma of diabetics (n = 200) differed significantly (p less than 0.001) from those of a hospitalized nondiabetic population (n = 163)--the latter mean being essentially the same for ambulatory subjects (n = 145), expectant mothers (n = 58), and patients with renal failure (n = 31), regardless of sex. In the diabetic group, values for plasma fructosamine correlated with those for glycated hemoglobin (r = 0.767, p less than 0.01) and glycated protein (r = 0.817, p less than 0.01). Values for plasma fructosamine were stable from day to day in patients with controlled blood glucose, but fluctuated in certain patients receiving only parenteral nutrition, even when their concentrations of glucose were normal and stable. We conclude that measurement of plasma fructosamine is suitable for assessing intermediate-term control of blood glucose when the turnover of plasma proteins is normal.

Antibiotic resistance and R plasmids in coliforms isolated from some Malaysian cooked foods

Forty samples of Malaysian cooked foods were examined for the presence of antibiotic-resistant coliforms and R plasmids. Twenty seven (68%) of the foods had antibiotic-resistant coliforms and 5 (13%) had R plasmids. Nineteen samples (48%) had total bacterial counts over 10(6) per gm and in 5 samples, no coliforms were detected. Our findings show that cooked food may be one possible way by which R plasmids are spread. The control of the spread of R plasmids is discussed.

Enterotoxin production by Staphylococcus aureus strains isolated from humans, foods and animals in Malaysia

Enterotoxin production by strains of Staphylococcus aureus isolated from human, food and animal sources was investigated. Of the 130 isolates studied, 27 (20.8%) were found to be enterotoxigenic. The most common enterotoxin detected from human sources was enterotoxin C whereas enterotoxin B occurred more frequently in staphylococcal strains of food origin. The 2 enterotoxigenic strains, from animals isolated from a dog and a goat, produced enterotoxins A and C, respectively. Enterotoxin E was not detected alone from any of the enterotoxigenic strains studied, but occurred together with other enterotoxins. The need to detect enterotoxin in staphylococcal strains and in suspected foods for the confirmation of staphylococcal food poisoning is discussed.

Enzyme-linked immunosorbent assay for the diagnosis of recent rubella infection

This paper presents further evidence of the sensitivity and reproducibility of ELISA for the detection of rubella antibody. This test can also be extended to include the diagnosis of recent rubella infections once the index of significance has been computed based on the estimated ELISA ratio of absorbance between the acute and convalescent serum samples. There is a greater than 90% agreement when compared to the results obtained by the haemagglutination-inhibition test. It should be further evaluated for rubella using purified rubella antigen to increase sensitivity and reproducibility.

Improved image position sensor for high resolution optical tracking

The narrow beamwidth of a laser source can provide advantages, relative to a microwave source, in applications such as short range, high angular resolution trackers. In such applications, an image position sensor (IPS) is used which senses the angle of arrival of the optical radiation from the target. It is shown analytically and empirically that, in the case of a rotating mirror IPS, cross coupling between azimuthal and elevation channels as well as nonlinear and saturation effects result when the image displacements on the rotating mirror are large compared to the image size. The performance of the rotating mirror IPS and consequently that of the tracker has been greatly enhanced by incorporating a computer generated variable density spatial filter (VDSF) in front of the rotating mirror.