Chronic Toxoplasma Infection Modifies the Structure and the Risk of Host Behavior

The intracellular parasite Toxoplasma has an indirect life cycle, in which felids are the definitive host. It has been suggested that this parasite developed mechanisms for enhancing its transmission rate to felids by inducing behavioral modifications in the intermediate rodent host. For example, Toxoplasma-infected rodents display a reduction in the innate fear of predator odor. However, animals with Toxoplasma infection acquired in the wild are more often caught in traps, suggesting that there are manipulations of intermediate host behavior beyond those that increase predation by felids. We investigated the behavioral modifications of Toxoplasma-infected mice in environments with exposed versus non-exposed areas, and found that chronically infected mice with brain cysts display a plethora of behavioral alterations. Using principal component analysis, we discovered that most of the behavioral differences observed in cyst-containing animals reflected changes in the microstructure of exploratory behavior and risk/unconditioned fear. We next examined whether these behavioral changes were related to the presence and distribution of parasitic cysts in the brain of chronically infected mice. We found no strong cyst tropism for any particular brain area but found that the distribution of Toxoplasma cysts in the brain of infected animals was not random, and that particular combinations of cyst localizations changed risk/unconditioned fear in the host. These results suggest that brain cysts in animals chronically infected with Toxoplasma alter the fine structure of exploratory behavior and risk/unconditioned fear, which may result in greater capture probability of infected rodents. These data also raise the possibility that selective pressures acted on Toxoplasma to broaden its transmission between intermediate predator hosts, in addition to felid definitive hosts

Perinatal outcome in singleton pregnancies complicated with preeclampsia and eclampsia in Ecuador

Preeclampsia in Ecuador is an understudied subject since available epidemiological data are scarce. The aim of this study was to describe perinatal outcomes among singleton pregnancies complicated with preeclampsia and eclampsia in a sample of low-income Ecuadorian women. Pregnant women complicated with preeclampsia (mild and severe) and eclampsia (defined according to criteria of the ACOG) delivering at the Enrique C. Sotomayor Obstetrics and Gynecology Hospital, Guayaquil, Ecuador were surveyed with a structured questionnaire containing maternal (socio-demographic) and neonatal data. Perinatal outcomes were compared according to severity of clinical presentation. A total of 163 women with preeclampsia [mild (23.9%), severe (68.7%) and eclampsia (7.4%)] were surveyed. Perinatal mortality and stillbirth rate was similar among studied groups (mild vs. severe preeclampsia/eclampsia cases). However, severe cases displayed higher rates of adverse perinatal outcomes: lower birth Apgar scores, more preterm births, and more low birth weight and small for gestational age infants. Caesarean-section rate and the number of admissions to intensive or intermediate neonatal care were higher in severe cases. A similar trend was found when analysis excluded preterm gestations. In conclusion, in this specific low-income Ecuadorian population perinatal outcome was adverse in pregnancies complicated with severe preeclampsia/eclampsi