RESUMEN
Field research with vectors is an essential aspect of vector biology research and vector-borne disease prevention and control. This type of research, which brings experimental vector manipulations into endemic areas, can present risks to human populations. This paper seeks to stimulate a full discussion within the medical entomology community of the risks associated with vector field research. Such discussions will promote development of a consensus, among investigators, sponsoring agencies and the communities within which the work is done, so that appropriate steps can be taken to minimize and manage the risks, and adequate oversight can be maintained.
Asunto(s)
Vectores Artrópodos , Bioética , Salud Pública , Investigación/normas , Animales , Investigación Biomédica , Ética en Investigación , Humanos , Consentimiento Informado , Comité de Profesionales , Proyectos de Investigación , Sujetos de Investigación , Medición de RiesgoRESUMEN
The sensitivities of the binding step and the lytic step of haemolysis by pneumolysin to the action of various inhibitors and to variations in the assay conditions were studied. Binding was inhibited by HgCl2 and N-ethylmaleimide. Lysis by previously fixed lysin was insensitive to HgCl2 and only slightly sensitive to N-ethylmaleimide. Binding of pneumolysin was independent of ionic strength. Binding of pneumolysin and streptolysin O decreased above pH 8-0 and 8-4 respectively. These results suggest that binding requires a non-ionized unsubstituted sulphydryl group. Incubation of erythrocytes with NaF caused inhibition of pneumolysin, indicating that some metabolic function of the cell may be involved in lysis. The action of streptolysin O was not affected by NaF.
Asunto(s)
Proteínas Hemolisinas/metabolismo , Sitios de Unión/efectos de los fármacos , Hemólisis/efectos de los fármacos , Concentración de Iones de Hidrógeno , Concentración Osmolar , Fluoruro de Sodio/farmacología , Reactivos de Sulfhidrilo/farmacologíaRESUMEN
Partial P1 nuclease digestion of 5'-32P-labeled tRNAs, followed by polyacrylamide gel electrophoresis and autoradiography, results in a series of bands of unequal intensities. Comparison of the digestion profiles of two conformers of yeast tRNA3Leu shows that P1 nuclease is sensitive to structural features of its substrate. Examination of the digestion pattern of yeast tRNAPhe in light of its known three-dimensional conformation shows that the enzyme's activity reflects the primary, secondary and tertiary levels of tRNA structure.