Pyruvate kinase is post-translationally regulated by sirtuin 2 in Aedes aegypti mosquitoes.

We previously demonstrated that Aedes aegypti pyruvate kinase (AaPK) plays a key role in the regulation of both carbon and nitrogen metabolism in mosquitoes. To further elucidate whether AaPK can be post-translationally regulated by Ae. aegypti sirtuin 2 (AaSirt2), an NAD+-dependent deacetylase that catalyzes the removal of acetyl groups from acetylated lysine residues, we conducted a series of analysis in non-starved and starved female mosquitoes. Transcriptional and protein profiles of AaSirt2, analyzed by qPCR and western blots, indicated that the AaSirt2 is differentially modulated in response to sugar or blood feeding in mosquito tissues dissected at different times during the first gonotrophic cycle. We also found that AaSirt2 is localized in both cytosolic and mitochondrial cellular compartments of fat body and thorax. Multiple lysine-acetylated proteins were detected by western blotting in both cellular compartments. Furthermore, western blotting of immunoprecipitated proteins provided evidence that AaPK is lysine-acetylated and bound with AaSirt2 in the cytosolic fractions of fat body and thorax from non-starved and starved females. In correlation with these results, we also discovered that RNAi-mediated knockdown of AaSirt2 in the fat body of starved females significantly decreased AaPK protein abundance. Notably, survivorship of AaSirt2-deficient females maintained under four different nutritional regimens was not significantly affected. Taken together, our data reveal that AaPK is post-translationally regulated by AaSirt2.

Homemade Dart Attacks in Hawai'i.

Over a 4.5-year period (September 2014 to March 2019), 7 patients presented to the State's only Level I Trauma Center with penetrating injuries inflicted by homemade metallic darts. Previously described in Micronesia, these are the first domestic cases of assaults utilizing this type of weaponry. Retrospective chart review was conducted for all patients who presented to our institution with a dart injury within the study period. Details regarding demographics, imaging, and patient management were collected and described herein. All 7 patients were male with a median age of 24.6 years impaled with darts that penetrated through the deep muscle and tissue layers of the neck, torso, or extremity. Three patients required operative intervention and no mortalities were observed. The depth of penetration and proximity to vital structures highlight the potential for life-threatening injuries from these homemade darts.