Paraquat-Mediated Oxidative Stress in Anopheles gambiae Mosquitoes Is Regulated by An Endoplasmic Reticulum (ER) Stress Response

Physiological and developmental dysfunctions in the dengue vector Culex pipiens (Diptera: Culicidae) immature stages following treatment with zinc oxide nanoparticles

The medical value of mosquitoes attracted researchers worldwide to search for a valuable way to control such serious insects. The continuous development of resistance against chemical insecticides pushed toward looking for novel and promising compounds against mosquitoes. In this study, the toxicity and physio-developmental effects of 10-30 nm spherical zinc oxide nanoparticles (ZnONPs) in aqueous suspension was addressed against the first larval instar of Culex pipiens mosquito. The calculated value of LC₅₀ was about 0.892 g/L while the sub lethal concentration LC₂₀ recorded about 0.246 g/L. Larvae treated with ZnONPs suffered reduced growth rate, longer developmental period and malformations in the breathing tube. Furthermore, the treated larvae showed clear abnormal appearance of the gastric caeca and midgut epithelia under transmission electron microscope (TEM). These abnormalities appeared as condensation of the nuclear chromatin, abnormal shape or absence of microvilli, highly increased amount of smooth endoplasmic reticulum in the cytoplasm and appearance of numerous vacuoles. Additionally, ZnONPs interfered with several biochemical pathways such as induction of oxidative stress which appeared in the form of increased levels of hydrogen peroxide and inability to activate the detoxifying enzymes alkaline phosphatase (ALP), catalase and glutathione peroxidase (GPX). On the contrary, the activity of the antioxidant enzyme superoxide dismutase (SOD) increased in treated larvae. Furthermore, LC₂₀ and LC₅₀ of ZnONPs inhibited the growth rate of the larval gut fauna in vitro. These results clearly show that ZnONPs target several tissues leading to serious alteration in the physiological and developmental processes in C. pipiens mosquito larvae.

Associations between Self-Rated Health and Perinatal Depressive and Anxiety Symptoms among Latina Women

PURPOSE

The objective of this study was to determine whether decreases in or consistently low preconception to pregnancy self-rated health (SRH) were associated with perinatal depressive and anxiety symptoms among Latinas.

METHODS

This is a secondary data analysis of 153 perinatal Latinas. Three groups were created to capture SRH from preconception to pregnancy: a decline in ratings, consistently low, and good+ (i.e., good, very good, or excellent). SRH was measured using two questions about their perceived physical health before and during pregnancy. Depressive symptoms and anxiety symptoms were assessed in the third trimester and six weeks postpartum using the Edinburgh Postnatal Depression Scale and State-Trait Anxiety Inventory, respectively. Life stressors were assessed in pregnancy using a modified version of the Life Experiences Survey. Linear regressions tested the associations.

RESULTS

Women with consistently low (i.e., fair or poor) SRH reported significantly more prenatal depressive symptoms than women who reported consistently good+ SRH. Women who reported a decline in SRH to fair or poor reported more prenatal anxiety symptoms but decreased postpartum anxiety symptoms than women who reported consistently good+ ratings. Life stressors were positively associated with prenatal depressive and anxiety symptoms.

CONCLUSIONS

Healthcare practitioners should assess changes in SRH ratings to identify risks for prenatal depressive and anxiety symptoms among Latinas, who have elevated rates of depressive and anxiety symptoms compared to non-Hispanic White women. Policymakers should provide healthcare providers with mental health resources to support at-risk Latinas during the prenatal period.