Biomedical subjects

S E Hoffner

Publications and source records attributed to S E Hoffner.

57 records · Page 4Linked to original sources

PubMed1987

Synergistic effects of antimycobacterial drug combinations on Mycobacterium avium complex determined radiometrically in liquid medium.

A technique to determine the effects of combining antimycobacterial drugs in liquid medium employing the radiometric growth readings in the Bactec system was tested using 20 Mycobacterium avium complex strains. Ten of the strains had been isolated from children with lymphadenopathy and ten from adults with pulmonary disease. All isolates were resistant to streptomycin, rifampicin, isoniazid and ethambutol when tested with a conventional resistant ratio technique on Löwenstein-Jensen medium. Synergistic interactions were shown for the two-drug combinations streptomycin + ethambutol and ethambutol + rifampicin against all 20 strains. Good efficacy was also found for all three-drug combinations containing ethambutol. Thus, although most isolates of the Mycobacterium avium complex are resistant to first-line antituberculous drugs when tested individually, they are susceptible in vitro to certain combinations of these drugs. This rapid radiometric assay is an efficient means for detecting such synergy.

Adult↗

PubMed1985

Estimation of heat production by cultured cells in suspension using semi-automated flow microcalorimetry.

Modifications to a heat conduction flow microcalorimeter are described which allow registration of heat production by cells cultured in suspension. LS cells produced 34 +/- 3 pW per cell. Over an 8.5 h period, cell numbers increased by 9% and heat production per cell by 18%. Oxygen consumption per cell was 0.244 +/- 0.02 mumol min-1 per 10(8) cells and the enthalpy change was -836 kJ/mol O2. An automated pumping system allowed sequential registration of heat production by untreated cells and those exposed to a metabolic inhibitor. The results showed that 0.1 mM 2,4-dinitrophenol caused a greater increase in power (+65% at 1.5 h) than in oxygen consumption (+36%). The opposite occurred in the case of cells treated with 1 mM potassium cyanide, heat dissipation being depressed (-48%) slightly less than oxygen uptake (-52%). The results illustrate the potential of careful calorimetric determinations in studying metabolic events in the growth and division of cells in culture.

2,4-Dinitrophenol↗

PubMedDate not supplied

Does vaccination with bacille Calmette-Guérin protect against AIDS?

In the United States a majority of patients with AIDS are infected with bacteria of the Mycobacterium avium complex (MAC), while in Sweden only approximately 10% of AIDS patients are so infected. It is proposed that general vaccination with bacille Calmette-Guérin (BCG) in Sweden may have induced protection not only against tuberculosis but also against infections with MAC, accounting for the lower incidence of MAC infection in Swedish patients with AIDS. The current AIDS pandemic may indicate a need for reevaluation of national BCG vaccination policies.

Acquired Immunodeficiency Syndrome↗