The objectives of these GLP US EPA OPPTS 970.3800 and 970.3700 studies were to examine the effects of tetrabromobisphenol A (TBBPA) at oral doses of 10, 100 or 1000 mg/kg BW/day over the course of 2 generations on growth as well as behavioral, neurological and neuropathologic functions in offspring. In a separate study the influence of oral TBBPA (0, 100, 300 or 1000 mg/kg BW/d) was examined on embryonic/fetal development from gestation days (GDs) 0-19. In the reproductive study, exposure to ≥ 100-mg/kg BW/d TBBPA resulted in a decrease in circulating, peripheral thyroxine (T4) levels in rats that were not accompanied by any marked alterations in triiodothyronine (T3) and thyroid stimulating hormone (TSH). These findings are explainable on the basis of induction of rat liver catabolism, a phenomenon that may be species-specific and not relevant for humans. TBBPA at up to 1000 mg/kg BW/d was not associated with any significant non-neurological effects on reproduction, growth and development. A subtle reduction, of unknown biological relevance, in the thickness of the parietal cortices of 11-day-old F2 pups in the 1000 mg/kg BW/d group was noted. This change was not accompanied by evidence of micro-anatomic changes. No estrogenic effects sufficient to affect macro and micro anatomy, fertility, reproduction, development, survival or behavior were detected in the embryofetal development study or in the multigenerational study. No other TBBPA-related effects on developmental neurotoxicity/neuropathology were detected. In the developmental study no TBBPA related change in mortality rate was observed in any of the dams. No other significant test article-related effects were noted. The no observed effect level (NOEL) for maternal and developmental toxicity was 1000 mg/kg BW/d, the highest dose evaluated.

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The green anole (Anolis carolinensis) is the most northerly distributed of its Neotropical genus. This lizard avoids a winter hibernation phase by the use of sun basking behaviors. Inevitably, this species is exposed to high doses of ambient solar ultraviolet radiation (UVR). Increases in terrestrial ultraviolet‐B (UV‐B) radiation secondary to stratospheric ozone depletion and habitat perturbation potentially place this species at risk of UVR‐induced immunosuppression. Daily exposure to subinflammatory UVR (8 kJ/m2/day UV‐B, 85 kJ/m2/day ultraviolet A [UV‐A]), 6 days per week for 4 weeks (total cumulative doses of 192 kJ/m2 UV‐B, 2.04 × 103 kJ/m2 UV‐A) did not suppress the anole's acute or delayed type hypersensitivity (DTH) response to horseshoe crab hemocyanin. In comparison with the available literature UV‐B doses as low as 0.1 and 15.9 kJ/m2 induced suppression of DTH responses in mice and humans, respectively. Exposure of anoles to UVR did not result in the inhibition of ex vivo splenocyte phagocytosis of fluorescein labeled Escherichia coli or ex vivo splenocyte nitric oxide production. Doses of UV‐B ranging from 0.35 to 45 kJ/m2 have been reported to suppress murine splenic/peritoneal macrophage phagocytosis and nitric oxide production. These preliminary studies demonstrate the resistance of green anoles to UVR‐induced immunosuppression. Methanol extracts of anole skin contained two peaks in the ultraviolet wavelength range that could be indicative of photoprotective substances. However, the resistance of green anoles to UVR is probably not completely attributable to absorption by UVR photoprotective substances in the skin but more likely results from a combination of other factors including absorption by the cutis and absorption and reflectance by various components of the dermis.

The plasma and peripheral blood mononuclear cell (PBMC) titer of feline immunodeficiency virus (FIV) in experimentally infected cats was assessed following administration of either zidovudine or cyclosporine. Treatments were begun 24 h post infection (p.i.) and continued for 4 weeks. Zidovudine treatment did not prevent establishment of infection with FIV, but plasma virus titers were significantly lower than controls at 2 weeks p.i. This reduction of plasma virus titer by zidovudine was not maintained at subsequent sampling times. Similarly, cyclosporine treatment initially lowered plasma virus titers at 2 weeks p.i., but at 4 weeks p.i. the plasma virus titers in cyclosporine-treated cats were significantly higher than in the untreated group. In the untreated group, plasma virus titers declined rapidly to an undetectable level by 14 weeks p.i. Neither zidovudine or cyclosporine treatment significantly influenced the titer of FIV in PBMCs. In all groups (untreated, zidovudine and cyclosporine) the titers in PBMC were high for the duration of the experiment. The decline in plasma virus titers in immunocompetent cats combined with the effect of cyclosporine on plasma titers strongly suggest that the immune system plays a major role in clearing FIV from plasma. In contrast, it appears that the immune response has little impact on PBMC virus titers. This shows that for complete assessment of antiviral agents, both cell-free and cell-associated virus titers must be examined. We also suggest that the limitation of viral titers in PBMC may be of critical importance in the control of lentiviral infection.

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