Biomedical subjects

R Hamilton

Publications and source records attributed to R Hamilton.

At least 145 records · Page 8Linked to original sources

PubMed1977

Activities of various 4-aminoquinolines against infections with chloroquine-resistant strains of Plasmodium falciparum.

The studies reported here stemmed from a personal report by Geiman on the capacity of the 4-aminoquinoline amodiaquin to inhibit in vitro maturation of ring stages of the chloroquine-resistant Monterey strain of Plasmodium falciparum. This observation, confirmed in owl monkeys infected with this strain, led to a comparison of the activities of chloroquine, amodiaquin, amopyroquin, and dichlorquinazine (12,278 RP) against infections with various chloroquine-susceptible and chloroquine-resistant strains. The results showed that: (i) these 4-aminoquinolines were essentially equally active against infections with chloroquine-susceptible strains and (ii) the activities of amodiaquin, amopyroquin, and dichlorquinazine were reduced significantly in the face of chloroquine resistance, but (iii) well-tolerated doses of these compounds would cure infections with strains that fully resisted treatment with maximally tolerated doses of chloroquine. Two other 4-aminoquinolines, SN-8137 and SN-9584, which also exhibited activity against chloroquine-resistant parasites in vitro, displayed curative activity in monkeys infected with a chloroquine-resistant strain. These observations show that there is cross-resistance among the 4-aminoquinolines, confirming earlier findings, but indicate that the dimensions of this phenomenon are sufficiently limited so that some derivatives are therapeutically effective against infections refractory to maximally tolerated doses of chloroquine.

Aminoquinolines↗

PubMed1977

Acid-base balance and plasma composition in the aestivating lungfish (Protopterus).

Upon entering into aestivation, Protopterus aethiopicus develops a respiratory acidosis. A slow compensatory increase in plasma bicarbonate suffices only to partially restore arterial pH toward normal. The cessation of water intake from the start of aestivation results in hemoconcentration and marked oliguria. The concentrations of most plasma constituents continue to increase progressively, and the electrolyte ratios change. The increase in urea concentration is disproportionately high for the degree of dehydration and constitutes an increasing fraction of total plasma osmolality. Acid-base and electrolyte balance do not reach a new equilibrium within 1 yr in the cocoon.

Acclimatization↗

PubMed1977

Clinical, laboratory, and epidemiologic features of a viral gastroenteritis in infants and children.

We studied 27 infants admitted to the hospital with acute diarrhea caused by human rotavirus (HRV) and obtained additional data on fecal excretion from ten outpatients with the same infection. The disease was characterized by watery diarrhea with fever and vomiting at the onset, isotonic dehydration, compensated metabolic acidosis, and increased concentrations of sodium and chloride but low concentrations of sugar in stools. Diarrhea usually ceased in three to four days when oral feedings were reduced or stopped but recurred mildly in four patients. Of 57 household contacts, 12 were symptomatic, 6 had HRV in their stools, and 19 had significantly increased serum HRV antibody titers. These features of the disease accord with available information on the pathogenesis of HRV infection. Knowledge of the clinical pattern of this newly diagnosable infection should help physicians to recognize and treat quickly this highly infectious, potentially dangerous illness.

Adult↗

PubMed1977