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Biomedical subjects

R O McAlister

Publications and source records attributed to R O McAlister.

9 recordsLinked to original sources
PubMed1989

HIV testing in prisoners: is mandatory testing mandatory?

We studied 977 newly incarcerated Oregon inmates to compare voluntary versus mandatory human immunodeficiency virus antibody (HIVAb) testing in the prison setting. All inmates were offered HIVAb counseling and testing. Blood drawn for routine syphilis serology from those who declined this offer was also tested for HIVAb after personal identifiers had been removed. Only 1.2 percent (12) prisoners were HIV positive. However, 62.5 percent (611) inmates were at risk for HIV infection by being an intravenous drug user, a male homosexual, or hepatitis B core antibody (HBcAb) positive. The ratio of at-risk, as yet uninfected inmates to those already HIV infected was 53 to 1. Two-thirds of all inmates including those at-risk chose to receive counseling and testing. In areas where most at-risk inmates are not yet infected, it may be more appropriate for HIV prevention activities in prison to focus on voluntary programs that emphasize education and counseling rather than mandatory programs that emphasize testing.

Adolescent↗
PubMed1988

Trial of anonymous versus confidential human immunodeficiency virus testing.

Before December, 1986, all public human immunodeficiency virus (HIV) testing in Oregon was done confidentially (using names). In December, clients were offered the option of either anonymous or confidential services. As judged by questionnaire responses, the availability of anonymity increased overall demand for testing by 50%: 125% for homosexual/bisexual (gay) men, 56% for female prostitutes, 17% for intravenous drug users, and 32% for other clients. The number of gay clients who had tests increased from a mean of 42 per month during the 4 months before anonymity was available to 108 per month during the 4 months after, whereas, at public sites in Colorado or California and private sites in Oregon, the number of gay clients tested did not increase. Twice as many seropositive persons were identified during the 3 1/2 months after anonymity became available (n = 85) as in the 3 1/2 months before (n = 36). Thus, availability of anonymous HIV testing and counselling drew gay men who had not sought services under a confidential testing system.

California↗
PubMed1977

Time-dependent loss of invasive ability of Plasmodium berghei merozoites in vitro.

UNLABELLED: The invasive ability of Plasmodium berghei merozoites in vivo was studied following their artificial removal from parasitized mouse red cells using complement-mediated immune lysis in vitro and in vivo. Time-course experiments revealed that lysed preparations contained two components contributing to the parasites' infectivity in mice. One component, presumed to be free merozoites released from mature schizont-infected cells, rapidly lost infectivity with time at 1 to 2 C. A second minor component appeared to have more stability at this temperature, and could be accounted for as intact parasitized cells containing mature schizonts not lysed by the complement in vitro, but lysed by the recipients' plasma complement in vivo. Further experiments revealed that suspension of parasitized cells in an isotonic diluent and centrifugation at moderate speeds substantially removes the number of invasive free merozoites insolable from a given sample of infected blood by immune hemolysis. CONCLUSIONS: merzoites, either contained within the confines of mature schizont-infected cells, or artificially removed from host cells, rapidly lose the ability to invade susceptible erythrocytes in vivo when suspended in an isotonic medium and held at 1 to 2 C in vitro.

Animals↗
PubMed1977

Studies on the invasive ability of malarial merozoites (Plasmodium berghei).

Studies were performed to evaluate several methods for the artificial removal of Plasmodium berghei merozoites from infected mouse erythrocytes. These methods, many of which have been reported to yield free parasites capable of establishing a patent infection when injected into a suitable host, included NH4C1-mediated lysis, complement-mediated immune lysis, pressure filtration, and multiple-burst and continuous-flow sonication. Free parasites isolated from infected mouse blood were examined in vitro under conditions known to support merozoite invasion, and were found to be noninvasive, irrespective of the method used for their isolation. Although all methods tested achieved high degrees of lysis, none removed all intact parasitized erythrocytes. Using multiple-burst and continuous-flow sonication, the infective potential of free parasite preparations could be accounted for solely on the basis of the intact parasitized cells contaminating the free parasite preparations.

Animals↗
PubMed1976

Schizont-infected cell enrichment in rodent malaria.

Mouse erythrocytes parasitized with Plasmodium berghei or Plasmodium yoelii were separated by ultracentrifugation using preformed isodensity gradients of the discontinuous type. Three fractions were obtained following centrifugation, the upper of which contained greater than 90% of all schizont-infected cells added to the gradient. The gradient material, Stractan II, is an arabinogalactan polysaccharide and appears to yield results similar to those available using gradients of bovine serum albumin. Cells are not altered morphologically or physiologically (as assessed by infectivity) by the treatment.

Animals↗