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The number of chemicals in commerce which have not been evaluated for potential developmental toxicity is large. Because of the time and expense required by conventional developmental toxicity tests, an abbreviated assay is needed that will preliminarily evaluate otherwise untested chemicals to help prioritize them for conventional testing. A proposed short-term in vivo assay has been used in a series of studies in which a total of 60 chemicals were tested. Some were independently tested two or four times each. In this preliminary test, pregnant mice were dosed during mid-pregnancy and were then allowed to deliver litters. Litter size, birth weight, and neonatal growth and survival to postnatal day 3 were recorded as indices of potential developmental toxicity. Results in this assay and conventional mouse teratology tests were generally concordant. Conventional data were available for 14 chemicals (ten teratogens, one fetotoxin, three nonteratogens), of which 11 (nine teratogens, one fetotoxin, one nonteratogen) produced evidence of developmental toxicity. This included conventional data for three chemicals (ethylene glycol, diethylene glycol dimethyl ether, and triethylene glycol dimethyl ether) that were untested before the present study. As high priority candidates for conventional testing on the basis of results here, all were subsequently studied in a standard teratology assay and were confirmed to be teratogenic in mice. Additionally, one of them (ethylene glycol) plus a fourth high priority candidate for conventional study (diethylene glycol monomethyl ether) were subsequently tested in rats and were found to be teratogenic in that species.

This study retrospectively analyzed demographic factors that may affect the prevalence of intestinal parasites among Guatemalan school children. The findings of the study showed that young age, wet season, female gender, and severe malnutrition all correlated positively with increased rates of infection. Clinical visits were performed on 10,586 school children aged 5-15 years over a four-year period (2004-2007) in the Palajunoj Valley of Guatemala, during which 5,705 viable stool samples were screened for infection with the following parasites: Ascaris lumbricoides, Giardia lamblia, Entamoeba histolytica, Hymenolepis nana, and Blastocystis hominis. The average overall prevalences of infection for specific parasites were A. lumbricoides 17.7%, E. histolytica 16.1%, G. lamblia 10.9%, H. nana 5.4%, and B. hominis 2.8%. Statistical analysis showed significantly higher rates of infection among younger children with G. lamblia (odds ratio [OR]=0.905, 95% confidence interval [CI] 0.871-0.941, p<0.0001) and E. histolytica (p=0.0006), greater prevalence of H. nana among females (OR=1.275, CI 1.010-1.609, p=0.0412), higher infection rates during the wet season for E. histolytica (p=0.0003) and H. nana (OR=0.734, CI 0.557-0.966, p=0.0275), and greater rates of infection with G. lamblia among malnourished children (for moderately malnourished children OR=1.498, CI 1.143-1.963, p<0.0001) and E. histolytica (for mildly malnourished children OR=1.243, CI 1.062-1.455, p=0.0313). The results suggest that the prevalence of gastrointestinal parasites among young Guatemalan children is highly dependent on the specific species of the parasite.

The olfactory ability of the convergent lady beetle, Hippodamia convergens Gué rin-Mé neville, was investigated using an 8-arm airßow olfactometer. Lady beetles tested were normal or had their antennae, antennal tips, or maxillary palps amputated. Normal beetles and those with their maxillary palps removed were highly attracted by the odor of radish leaves infested with green peach aphids, Myzus persicae (Sulzer). Beetles with their antennae or antennal tips removed were not attracted. In addition, the normal lady beetles were signiÞcantly attracted to clean radish leaves. These results indicate that H. convergens can perceive olfactory stimuli released by their prey and their preyÕs host plant (or a combination of the two) and that the beetlesÕ olfactory receptors are located principally on the tips of their antennae. Also as part of this study, the antennal sensilla of male and female convergent lady beetles were examined using scanning electron microscopy. The sensilla were counted, the majority of which were located on the terminal segment, and 4 morphological classes were identiÞed: chetiform, Bö hm, basiconic, and trichoid. Chetiform sensilla were observed on all 11 antennal segments, while the Bö hm sensilla were located only on the Þrst two segments. The basiconic and trichoid sensilla were located exclusively on the terminal two segments. The most abundant sensilla on the terminal segment, trichoid sensilla, were suggested to function in olfaction.