Unveiling Tst3, a Multi-Target Gating Modifier Scorpion α Toxin from Venom of Northeast Brazil: Evaluation and Comparison with Well-Studied Ts3 Toxin of .

Studies on the interaction sites of peptide toxins and ion channels typically involve site-directed mutations in toxins. However, natural mutant toxins exist among them, offering insights into how the evolutionary process has conserved crucial sequences for activities and molecular target selection. In this study, we present a comparative investigation using electrophysiological approaches and computational analysis between two alpha toxins from evolutionarily close scorpion species of the genus , namely, Tst3 and Ts3 from and , respectively.

Ts17, a Tityus serrulatus β-toxin structurally related to α-scorpion toxins.

Ts17 was purified from the venom of the scorpion Tityus serrulatus, the most dangerous scorpion species in Brazil. The activity on Na1.1-Na1.

Slums and pandemics.

How do slums shape the economic and health dynamics of pandemics? A difference-in-differences analysis using millions of mobile phones in Brazil shows that residents of overcrowded slums engaged in less social distancing after the outbreak of Covid-19. We develop and calibrate a choice-theoretic equilibrium model in which individuals are heterogeneous in income and some people live in high-density slums. Slum residents account for a disproportionately high number of infections and deaths and, without slums, deaths increase in non-slum neighborhoods.

Avoidable environmental disasters and infant health: Evidence from a mining dam collapse in Brazil.

We study the health consequences of one of the largest environmental disasters of the world mining industry, which largely stemmed from regulatory failure. Exploiting the timing and location of the Mariana mine tailings dam collapse in Brazil, we show that in utero exposure to the tragedy significantly reduced birth weight and increased infant mortality. The adverse effects were stronger for infants born to less educated and nonmarried mothers.