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D Carpenter

Publications and source records attributed to D Carpenter.

At least 91 records · Page 5Linked to original sources
PubMed1976

Heterogeneity of Staphylococcus aureus enterotoxin B as a function of growth stage: implications for surveillance of foods.

Staphylococcus aureus was grown in a fermentor under controlled conditions of pH, oxygenation, and temperature, while the higher-molecular-weight products of its growth were continuously removed across ultrafiltration membranes. These products were examined by single and double gel diffusion and immunoelectrophoresis against a variety of available anti-enterotoxin B antisera. All antisera examined were polyvalent for S. aureus antigens. However, two electrophoretically distinct proteins were the major reactants with the antisera. One of these was present in early- to mid-log-phase cultures. After mid-log growth was achieved, both were present but in continuously changing proportions. This observation was repeated with a variety of growth conditions and media. A significant part of the physicochemical heterogeneity of enterotoxin B observed over the past 20 years is thus correlated with the growth phase of the organism. Taken together, these facts are used to argue for a two-step rationale for the detection of food-borne staphylococcal disease: (i) screening for a presumptive hazard by analysis for any antigen, toxin, or enzyme of S. aureus in a foodstuff and (ii) confirmation of the hazard by identifying the presence of an enterotoxin using a combination of physicochemical and serological techniques.

Antigens, Bacterial↗
PubMed1975

Effect of ouabain and potassium-free solution on mammalian thermosensitive afferents in vitro.

Studies have been performed on the afferent fibers innervating the scrotal skin of the rat to test the hypothesis that the generator potential mechanism underlying cold thermosensitivity of these afferent fibers is an electrogenic sodium pump. In these experiments a pudendal nerve-scrotal skin preparation was isolated from the animal and maintained in oxygenated mammalian Ringer's where composition could be varied and drugs added. Application of ouabain resulted in an increae in the discharge of cold sensitive afferent fibers which was more pronounced at 38--41 degrees C than at temperature below 30 degrees C. In most of the cases transient accelerations on cooling were reduced, but often a transient response to warming appeared. The effects of ouabain administration were reversible. Removal of extracellular K at 35 degrees C resulted in an increased discharge of cold sensitive afferents. This observation is consistent with the effects of ouabain, since removal of extracellular K also block Na transport. The generator potential mechanism underlying cold sensitivity of these afferent fibers appears to be an electrogenic Na pump.

Afferent Pathways↗
PubMedDate not supplied

Three approaches to better disclosure.

Spurred by growing investor demands, numerous nonprofit health systems are expanding investor relations efforts - not creating new departments like their for-profit counterparts, but working harder to account for themselves to the bond market. "The more sophisticated players realize (greater disclosure) is coming, and they figure they might as well do it and do a great job at it and get ahead of the wave," says Martin Arrick, director of Standard & Poor's health care group. Here are case studies of three that are pushing ahead in that much-watched area--reporting more often, keeping in closer contact with their audiences than before, and , in at least one case, posting financials on the Web.

Capital Financing↗
PubMedDate not supplied

Handling bombshells.

Explore the source record for details and available documents.

Bankruptcy↗