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D J Krogstad

Publications and source records attributed to D J Krogstad.

93 records · Page 6Linked to original sources

The assessment of antimicrobial combinations.

The traditional approach to the study of the interaction between antimicrobial agents relies on the assumption that inhibition of growth by antimicrobial agents follows a linear dose-response curve. Because this assumption is invalid, we propose that antimicrobial combinations should be assessed by empiric dose-response curves that would distinguish synergistic, additive, and antagonistic effects on the rate of cell growth. This approach predicts synergy for the model combination of trimethoprim and sulfamethoxazole and should also be applicable to other combinations of antimicrobial agents nd to combinations of antitumor agents.

Anti-Bacterial Agents↗

Placental changes associated with fetal outcome in the Plasmodium coatneyi/rhesus monkey model of malaria in pregnancy.

Term placentas collected surgically from seven Plasmodium coatneyi-infected rhesus monkeys, one abortion, and five controls were evaluated histopathologically. The placentas from Plasmodium-infected dams had more significant pathologic changes than those from controls for six parameters (P < 0.05) and higher numbers of activated (LN5 + Zymed) macrophages in the intervillous space (IVS) (P = 0.0173). Total parasite load (TPL) was defined as the sum of all weekly peripheral infected red blood cell counts for each trimester and for the entire pregnancy. High first trimester PLs were more likely to result in fetal demise (P = 0.0476) or increased placental damage in surviving infants. As trimester 2-3 TPL increased, so did the number of activated macrophages (P < 0.05) and the total malaria pigment scores (P < 0.05). Low birth weight (LBW) and intrauterine growth retardation (IUGR) were associated with high pigment scores and high numbers of activated macrophages in the IVS. High placental damage scores were not associated with IUGR, LBW, or early infant mortality.

Animals↗

Pharmacokinetics of vancomycin in normal subjects and in patients with reduced renal function.

Recent novel clinical applications of vancomycin have stimulated reinvestigations of the pharmacologic properties of this drug. Absorption from the gastrointestinal tract is negligible, and oral administration is appropriate only for patients with certain staphylococcal and clostridial diarrheas. After intravenous administration (the intramuscular route being painful), vancomycin is excreted by glomerular filtration, with virtually total recovery in the urine. Distribution is consistent with a three-compartment open pharmacokinetic model. Serum half-life values are usually greater than 8 min in the distribution phase, 30 min to 1.5 hr in the intermediate phase, and between 5 and 11 hr in the elimination phase. The level of binding to human serum proteins is 55%. Since the relation between the vancomycin clearance and the creatinine clearance (but not the level of creatinine in serum) is linear in both normal and impaired renal function, a nomogram has been prepared that delineates dosages that will produce a mean steady-state concentration in serum of 15 micrograms/ml. Vancomycin penetrates well into pericardial, pleural, synovial, and ascitic fluid in humans, but concentrations in cerebrospinal fluid after parenteral administration may be insufficient for the successful treatment of certain cases of meningitis.

Administration, Oral↗