Pathology of falciparum malaria in Vietnam.

Autopsy samples from the brains of 20 patients who died of falciparum malaria were examined by light microscopy and by an immunohistologic method. Particular attention was paid to a comparison of the pathologic features of the white matter and the cortex. In the high-sequestration (greater than 50%) group (n = 8), the mean +/- SD percentage of cerebral microvessels that showed parasitized red blood cell (PRBC) sequestration was 71.2 +/- 8.1% in the cortex and 84.0 +/- 6.7% in the white matter. The difference in the PRBC sequestration rate between cortex and white matter was statistically significant (P less than 0.01). Perivascular and ring hemorrhages were seen more frequently in the white matter than in the cortex. Deposition of IgG and Plasmodium falciparum antigen in the cerebral microvessels was more highly significant in the white matter than in the cortex (P less than 0.01). Our study demonstrated that the localized concentration of PRBC sequestration in the brain correlated with the marked immunohistologic differences in the microvessels of cortex and white matter.     

Effects of IgM Allotype Suppression on Serum IgM Levels,B-1 and B-2 Cells,and Antibody Responses ir Allotype Heterozygous F1 Mice

IgM allotype heterozygous F1 mice were independently suppressed for Igh6a or Igh6b to evaluate the contribution of B-1 and B-2 cells to natural serum IgM levels and Ab responses. B-2 B cells expressing IgM of the suppressed allotype were evident in the spleens of suppressed mice 4 to 6 weeks after cessation of the suppression regimen, whereas B-1 B cells of the suppressed allotype were undetectable for up to 9 months. Although serum IgM of the suppressed allotype was initially depleted in mice suppressed for either allotype, by 7 months of age, there were detectable levels of IgM of the suppressed allotype in the serum; however, the levels were significantly below that found in nonsuppressed mice. When mice were immunized with either the T-independent or T-dependent form of phosphorylcholine, those suppressed for either allotype, and consequently depleted of B-1 B cells of that allotype, did not respond with phosphorylcholine-specific IgM of the suppressed allotype. In contrast, when mice were immunized with α1-3 dextran, the Igh6a allotype-suppressed mice were able to produce dextran-specific IgM of that allotype. These results show that allotype-bearing B-1 cells of both allotypes can be effectively suppressed by this suppression protocol and this produces long-lasting effects on B-1 cell levels and serum IgM of the suppressed allotype. These observations reflect the derivation of the majority of B-1 cells from fetal-neonatal precursors, which cannot be replaced by newly emerging B-2 cells of adult origin. Their ablation by antibody treatment results in permanent alterations to the adult B-cell repertoire.     

Effects of Repeated Deep Inspirations on Recovery from Methacholine-Induced Airway Narrowing in Normal Subjects

Background. A single deep inspiration (DI) is known to be a potent bronchodilator but it is not known if repeated DI can accelerate sustained recovery from bronchoconstriction. Methods. We induced sustained bronchoconstriction using increasing concentrations of nebulized methacholine (Mch) during tidal breathing and assessed airway narrowing by measuring respiratory resistance (Rrs) using forced oscillation in six healthy subjects. On separate days we examined the effects of DI every 3 minutes and of prohibition of DI on recovery of Rrs for 30 minutes after the end of Mch nebulization. Results. Bronchoconstriction (Rrs ∼ 150% above baseline) was induced. DI during recovery had a transient bronchodilator effect but no cumulative effect. At 30 minutes after end of nebulization (and 2 minutes after the last DI) Rrs was 87% above baseline compared to 93% above baseline when DI was prohibited. Conclusion. Recovery from induced bronchoconstriction with methacholine was slow (∼ 2%/min) and not accelerated by frequent DI.     

Income-related health inequality in Belgium: a longitudinal perspective

This paper provides new evidence on the degree of income-related inequality in self-assessed health in Belgium. First of all, we combine the time dimension, which has been shown to be very important in the analysis of inequality, and the use of the recently developed interval regression approach to transform a categorical health variable in a continuous one. Second, we measure how the long-run inequality differs from the short-run inequality. Finally, we decompose this health-related income mobility index as well as the long-run concentration index (CI) itself into its contributors. Using data from the panel survey of Belgian households (1994–2002), we find that health is pro-rich distributed and that its inequality is underestimated by 9.45% when neglecting the dynamics of individuals over time. Income, education, job status and age are the most important contributors in the CI and the difference between the short-run and long-run inequality.      

The parenting-crime connection

This paper examines delinquency as it relates to family influences.