Objective: Autoimmune retinopathy and hydroxychloroquine (HCQ)-related retinal toxicity share many similarities, raising the possibility autoimmunity plays a role in HCQ retinopathy. The objective of this study is to determine whether patients diagnosed with HCQ retinal toxicity are more likely to have circulating antiretinal autoantibodies (AAbs) compared to controls.
Methods: We tested plasma samples for the presence of anti-retinal AAbs by immunoblotting in 270 patients with systemic lupus erythematosus (SLE) receiving HCQ.
Dynamic models of many processes in the biological and physical sciences give systems of ordinary differential equations called compartmental systems. Often, these systems include time lags; in this context, continuous probability density functions (pdfs) of lags are far more important than discrete lags. There is a relatively complete theory of compartmental systems without lags, both linear and non-linear [SIAM Rev.
View Article and Find Full Text PDFA significant consideration in modeling systems with stages is to obtain models for the individual stages that have probability density functions (pdfs) of residence times that are close to those of the real system. Consequently, the theory of residence time distributions is important for modeling. Here I show first that linear deterministic compartmental systems with constant coefficients and their corresponding stochastic analogs (stochastic compartmental systems with linear rate laws) have the same pdfs of residence times for the same initial distributions of inputs.
View Article and Find Full Text PDFIn the presentation of his randomization test for paired data, Fisher used Darwin's data on the relative growth rates of cross- and self-fertilized corn to motivate the development. On reading Darwin's description of his experiment, it appears clear that the experiment did not use true paired comparisons. Although the statistical foundation of Fisher's randomization test is sound, it is of historical interest that it does not suit the design of the motivating experiment.
View Article and Find Full Text PDFAfter reviewing the evidence on the relation of vertical transmission of HIV to stage of infection in the mother, I developed a stochastic model of transmission in which the probability of transmission per week is proportional to the virus load in the mother. The virus load in different stages of the infection is measured by viral RNA levels or tissue culture infectious virus levels in plasma. The constant of proportionality is assumed to be different for transmission during pregnancy, during parturition, and during breast-feeding.
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