Risk of acquiring AIDS from salivary exchange through cardiopulmonary resuscitation courses and mouth-to-mouth resuscitation.

In summary, the risk of transmission of HIV and other infectious diseases by saliva during CPR training practice is extremely low because of low infectious virus titers and properties of saliva that inhibit HIV. However, it is necessary to perform decontaminations of mannequins, by application of a suitable disinfectant and by a mechanical wipe-down with a sponge, to cleanse the external buccal area of the mannequin after contact with each CPR trainee. For health care and public safety professionals training and performance of MTM ventilation during CPR should be carried out with barrier devices such as the bag-valve-mask or face shield. Guidelines and standards of the AHA, American Red Cross, and the CDC for prevention of infection during CPR and emergency cardiac care are more fully available elsewhere. If the recommended procedures are followed, the risk of acquiring HIV from saliva during MTM should be extremely low.

Influence of nutritional factors on growth and hydrolytic enzyme production in Nocardia asteroides.

The growth and production of hydrolytic enzymes such as alpha-amylase, esterase and peroxidase as influenced by the type of media, carbon and nitrogen sources and C:N ratio were monitored in Nocardia asteroides at 37 degrees C. Sabouraud dextrose and the synthetic media yielded maximum growth compared with tryptic soy broth. Among the carbon sources (dextrose, fructose, sucrose, maltose, starch and citrate), monosaccharides supported maximum growth and induced higher alpha-amylase activity but repressed the peroxidase activity. On the other hand, the disaccharides and starch produced less growth but induced maximum esterase and peroxidase activities. Glutamate among the nitrogen sources (nitrate, nitrite, ammonium, hydroxylamine, glutamate and casein) supported maximum growth. Glutamate, nitrate and casein induced alpha-amylase and esterase activities but suppressed peroxidase activity. Nitrite, ammonium and hydroxylamine stimulated peroxidase activity to the maximum but repressed alpha-amylase and esterase activities. Low, medium and high C:N ratios induced maximum peroxidase, esterase and alpha-amylase activities, respectively.

An automated blood culture system: the detection of anaerobic bacteria using a Malthus Microbiological Growth Analyser.

The Malthus Microbiological Growth Analyser has proved to be sensitive in detecting conductivity changes due to anaerobic metabolism in a number of widely used blood culture media. Freshly prepared cooked meat media and Thiol medium yielded the greatest gross conductivity changes, and were more sensitive of anaerobic metabolism than other media. Failure of the instrument to detect anaerobic metabolism was a problem particularly associated with growth in the thioglycollate medium. False positive detections of growth were attributed to a number of factors including electrode instability (6.0%) and bacterial contamination (8.75%).

Measurements and parameterization of the bidirectional reflectance factor of BaSO(4) paint.

Comprehensive measurements of the bidirectional reflectance factor of BaSO(4) paint vs both viewing and illumination angles are presented as contour plots. Contours resulting from several surfacing techniques are compared to demonstrate that a machined surface on a thick BaSO(4) deposit gives the most reproducible diffuse reflectivity. It is also shown that a spray deposit of BaSO(4) gives a much less diffuse reflectivity. We also show that the contours of bidirectional reflectance of either machined BaSO4 or smoked MgO may be described by a three-parameter fit, which automatically obeys the Helmholtz reciprocity theorem and is simply related to the efficiency of total reflectance.