Factors associated with the prevalence of neonatal abstinence syndrome in West Virginia.

Neonatal abstinence syndrome (NAS) is a group of problems associated with withdrawal symptoms of a newborn who was exposed to maternal opiate use while in the womb. West Virginia (WV) is of utmost concern as this state exhibits among the highest rates of opioid abuse and consequently, NAS. In this manuscript, we review factors associated with the prevalence of NAS in WV. We provide evidence suggesting that states exhibiting high Medicaid participation demonstrate a high NAS rate, further associating these two factors. Although a similar trend was observed in the substate geographic regions of WV, the presence of regional treatment facilities was negatively associated with NAS prevalence in WV, possibly suggesting that the establishment and utilization of more of these facilities may reduce NAS. Future research investigating factors that contribute to NAS is essential for the elimination of this syndrome.

The Role and Mechanism of Erythrocyte Invasion by Francisella tularensis.

Francisella tularensis is an extremely virulent bacterium that can be transmitted naturally by blood sucking arthropods. During mammalian infection, F. tularensis infects numerous types of host cells, including erythrocytes. As erythrocytes do not undergo phagocytosis or endocytosis, it remains unknown how F. tularensis invades these cells. Furthermore, the consequence of inhabiting the intracellular space of red blood cells (RBCs) has not been determined. Here, we provide evidence indicating that residing within an erythrocyte enhances the ability of F. tularensis to colonize ticks following a blood meal. Erythrocyte residence protected F. tularensis from a low pH environment similar to that of gut cells of a feeding tick. Mechanistic studies revealed that the F. tularensis type VI secretion system (T6SS) was required for erythrocyte invasion as mutation of mglA (a transcriptional regulator of T6SS genes), dotU, or iglC (two genes encoding T6SS machinery) severely diminished bacterial entry into RBCs. Invasion was also inhibited upon treatment of erythrocytes with venom from the Blue-bellied black snake (Pseudechis guttatus), which aggregates spectrin in the cytoskeleton, but not inhibitors of actin polymerization and depolymerization. These data suggest that erythrocyte invasion by F. tularensis is dependent on spectrin utilization which is likely mediated by effectors delivered through the T6SS. Our results begin to elucidate the mechanism of a unique biological process facilitated by F. tularensis to invade erythrocytes, allowing for enhanced colonization of ticks.