Biomedical subjects

E McConnell

Publications and source records attributed to E McConnell.

At least 37 records · Page 2Linked to original sources

PubMed1979

Duration of immunity following a single vaccination with irradiated sporozoites of Plasmodium berghei.

A rodent model of sporozoite immunization against malaria based on a single immunizing dose is described. The duration of protective immunity was measured as a function of dose, and the results suggest that the percentage of protection follows a bimodal distribution. The first peak occurs between days 7-12 after immunization, while the second peak occurs at approximately 28 days. Although the percentage of protection declines steadily after the second peak, some immunity was detectable as long as 140 days after immunization with the higher doses.

Animals↗

PubMed1979

The use of membrane screen filters in the isolation of Plasmodium berghei sporozoites from mosquitos.

An improved procedure is presented for the isolation of Plasmodium berghei sporozoites from host mosquitos. The method employs filtration through a series of Nuclepore membranes followed by two consecutive centrifugations of the filtrate layered over Renografin-60 solutions of different densities. A Coulter Counter was used to compare isolations prepared by this technique with those prepared by a routinely employed discontinuous gradient method. When the sporozoite concentration in each preparation was standardized at 300 sporozoites per ml, isolations prepared by the new technique were significantly cleaner than isolations prepared by the discontinuous gradient method, containing an average of 1706 total particles per ml compared with 46 107 total particles per ml. The latter procedure was more effective, however, in removing viable microorganisms. Sporozoites isolated by both techniques were similar in immunogenicity and virulence.

Animals↗

PubMed1976

Bancroftian filariasis and membrane filters: are night surveys necessary?

Paired day and night blood specimens from 41 persons living in a hyperendemic Wuchereria bancrofti area of southwestern Ethiopia were examined for microfilariae by Nuclepore filter, thick film, and counting chamber techniques. Filtering techniques were so highly sensitive that more infected persons were identified by filtering day blood than by examining night blood by conventional methods. Increasing the volume of blood filtered from 1 ml to 5 ml increased the number of positives identified during the day. Filtering 5 ml of day blood obviated the need for examining night blood, even though a high proportion of infected persons had very low numbers of circulating microfilariae.

Blood↗

PubMed1976