Reducing volunteer bias: using left-over specimens to estimate rates of HIV infection among inmates in Ontario, Canada.

OBJECTIVE: To estimate the prevalence of HIV-1 infection among adult and young offenders admitted to remand facilities in the province of Ontario, Canada, by using a design that reduces volunteer bias. METHODS: A study using a modified anonymous HIV-surveillance design was conducted with urine specimens routinely collected from male and female entrants to all Ontario jails, detention and youth centres between February and August 1993. Information on sex, age, and history of injecting drug use was also collected. Urine was screened using a modified commercial HIV enzyme-linked immunosorbent assay kit and confirmed using a modified in-house Western blot assay. RESULTS: Data were obtained on 10,530 adult men, 1518 adult women, 1480 young male offenders, and 92 young female offenders. Urine specimens were available for 88% of new entrants. Of the entrants, 1% (n = 163) refused to have their urine used for research. Refusals were not associated with history of injecting drug use. Overall rates of HIV-1 infection were 1% for adult men, 1.2% for adult women, and 0% for young offenders. Both the rates of infection and prevalence of injecting drug use varied across facilities and geographic regions. Overall, 13% of adult men, 20% of adult women, 3% of young male offenders, and 2% of young female offenders reported a history of injecting drug use. Rates of infection were highest among self-reported injecting drug users. Rates of HIV were 3.6% for adult men and 4.2% for adult women who injected compared with 0.6 and 0.5%, respectively, for non-injecting drug users. CONCLUSIONS: The use of unlinked left-over specimens is an important tool for measuring HIV-prevalence rates and should be encouraged. The results indicate that HIV rates are much higher among those entering prisons than in the general population. The pattern of HIV in Ontario prisons is similar to that reported in Europe and the United States. We are optimistic that these data will stimulate much needed efforts towards education and health promotion, and open the door to further research in Canadian prisons.

PGE2 and PGF2alpha biosynthesis in stimulated and nonstimulated peritoneal preparations containing macrophages.

The biosynthesis of PGE2 and PGF2alpha was measured in intact peritoneal exudate preparations obtained from C. parvum-treated and control C3H mice. Although both the control and stimulated preparations biosynthesized PGF2alpha and PGE2 from [1-14C] arachidonic acid, the stimulated preparations generated more of both prostaglandins than did nonstimulated preparations, probably as a result of increased synthesis within macrophages. Increased transformation of PGE2 into PGF2alpha by PGE2 9-ketoreductase was noted in stimulated preparations when compared to that in control cells. The data suggest that stimulated macrophages are capable of generating increased quantities of PGF2alpha and therefore might function as one source of this substance in resolving inflammatory reactions.

In vivo chemotaxis induced by polyunsaturated fatty acids.

Intradermal injection of as little as 500 ng of arachidonic acid or the metabolites from arachidonic acid incubated with soybean lipoxygenase produced infiltration of the upper dermis by polymorphonuclear leukocytes 18 hours after injection. In experiments comparing the chemotactic properties of four fatty acids in varying concentrations, oxidative products of arachidonic acid by soybean lipoxygenase were the most powerful followed by free arachidonic acid and free linoleic acid while stearic acid did not produce significant infiltration. These findings suggest that the elevated levels of free arachidonic acid and an arachidonic acid metabolite (12L-hydroxy-5, 8, 10, 14-eicosatetraenoic acid), recently found in psoriatic epidermis, may at least in part be attracting polymorphonuclear leukocytes into psoriatic skin.

Cholestrol and cholesteryl ester content in normal and pathologic scale.

Using a sensitive new assay, we have measured the cholesteryl ester and cholesterol contents of stratum corneum from callus, normal skin, psoriatic lesions (plantar and nonplantar), and lamellar ichthyotic lesions (plantar and nonplantar). Cholesteryl ester content of normal stratum corneum was significantly higher than that of callus, suggesting that callus was not a suitable control tissue for further biochemical studies involving sterol content of stratum corneum. Both psoriatic and lamellar ichthyotic scale have increased levels of free cholesterol and decreased levels of esterified cholesterol when compared to appropriate controls.