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Biomedical subjects

E Chernin

Publications and source records attributed to E Chernin.

At least 19 recordsLinked to original sources
PubMed1987

The disappearance of bancroftian filariasis from Charleston, South Carolina.

I suggest the hypothesis that bancroftian filariasis, endemic since the early days of slavery in Charleston, South Carolina, disappeared around 1930 by virtue of the long-term effects of a municipal sewerage-water system begun in the 1890s or thereabouts. These public works, originally intended to abate typhoid and related diseases, helped to eliminate filariasis by reducing the availability of polluted domestic waters which are the preferred breeding sites for the urban vector, Culex quinquefasciatus (= fatigans). Cause and effect having been separated by some three decades, the epidemiologic connections between these events in Charleston seem not to have been appreciated hitherto.

Culex↗
PubMed1986

Surgical maggots.

Explore the source record for details and available documents.

Chronic Disease↗
PubMed1980

Effector mechanism in the response of Schistosoma mansoni miracidia to snail-conditioned water.

Schistosoma mansoni miracidia respond to snail-conditioned water (SCW) by sharply increasing their rate of turning when they encounter abrupt decreases in stimulant concentration (Roberts et al., '79). We examined the role of the cilia and the subepithelial muscles in the turning behavior of stimulated miracidia. Several lines of evidence indicated that miracidia do not turn by altering their ciliary beat. Ciliary beating on detergent-treated miracidia was reactivated using solutions containing ATP and Mg2+. These organisms were unable to turn spontaneously, a characteristic of live miracidia. Several divalent cations which stimulate increased turning of intact miracidia failed to support ciliary reactivation of detergent-treated organisms. Further, intact miracidia increased their rate of turning in gradients of Mg2+, but detergent-treated organisms swimming in reactivation solution did not turn in Mg2+ gradients. High speed cinematography of intact miracidia swimming in gradients of SCW or Mg2+ illustrated that turning is invariably accompanied by flexion of the body. This bending occurred only at the transverse interciliary ridges between the first and second, and second and third tiers of ciliated plates. Flexion was not observed at the interciliary ridge between the third and fourth tiers of plates, suggesting that miracidia turn by contracting specific portions of their subepithelial musculature.

Adenosine Triphosphate↗
PubMed1979

Behavioral responses of Schistosoma mansoni miracidia in concentration gradients of snail-conditioned water.

Movement patterns of Schistosoma mansoni miracidia were examined in several concentrations and gradients of snail-conditioned water (SCW). Miracidia surrounded by uniform concentrations of SCW swam at the same speed and exhibited the same rate of turning (angular velocity) as did control miracidia swimming in spring water. However, miracidia in gradients of SCW exhibited a 3-fold increase in their angular velocity without altering their swimming speed. Miracidia ascending gradients of SCW did not increase their angular velocity and failed to orient to the gradient of the stimulant. In contrast, miracidia which encountered sufficiently abrupt decreases in SCW concentration, while descending the gradient, sharply increased their angular velocity. This behavior caused miracidia to remain in regions of high concentration of stimulant. The magnitude of decrease in SCW concentration needed to evoke this response depended on the absolute concentration of SCW. Thus, the miracidial response is a "boundary reaction", a form of chemoklinokinesis, and not a chemotaxis.

Animals↗