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To successfully feed on blood, hematophagous arthropods must combat the host’s natural hemostatic and inflammatory responses. Salivary proteins of blood-feeding insects such as mosquitoes contain compounds that inhibit these common host defenses against blood loss, including vasoconstriction, platelet aggregation, blood clotting, pain, and itching. The D7 proteins are some of the most abundantly expressed proteins in female mosquito salivary glands and have been implicated in inhibiting host hemostatic and inflammatory responses. Anopheles gambiae, the primary vector of malaria, expresses three D7 long-form and five D7 short-form proteins. Previous studies have characterized the AngaD7 short-forms, but the D7 long-form proteins have not yet been characterized in detail. Here, we characterized the A. gambiae D7 long-forms by first determining their binding kinetics to hemostatic agonists such as leukotrienes and serotonin, which are potent activators of vasoconstriction, edema formation, and postcapillary venule leakage, followed by ex vivo functional assays. We found that AngaD7L1 binds leukotriene C4 and thromboxane A2 analog U-46619; AngaD7L2 weakly binds leukotrienes B4 and D4; and AngaD7L3 binds serotonin. Subsequent functional assays confirmed AngaD7L1 inhibits U-46619-induced platelet aggregation and vasoconstriction, and AngaD7L3 inhibits serotonin-induced platelet aggregation and vasoconstriction. It is therefore possible that AngaD7L proteins counteract host hemostasis by scavenging these mediators. Finally, we demonstrate that AngaD7L2 had a dose-dependent anticoagulant effect via the intrinsic coagulation pathway by interacting with factors XII, XIIa, and XI. The uncovering of these interactions in the present study will be essential for comprehensive understanding of the vector-host biochemical interface. [ABSTRACT FROM AUTHOR]

Steam injection with catalysts is a method with high potential for heavy crude oil recovery and the fulfillment of fuel demand. This investigation aims to evaluate dispersed catalysts, produced in catalytic aquathermolysis, under hydrotreating conditions to improve the properties of heavy crude oils. The hydrotreating process of the improved crudes obtained in the catalytic aquathermolysis on a Colombian heavy crude of 12.8°API was analyzed. The aquathermolysis tests were conducted under conditions typical of steam injection, a widely used technology for enhanced oil recovery. Iron and molybdenum naphthenates were used as precursors. The upgraded crude oils showed a decrease in viscosity up to 90 % in comparison to non-catalytic aquathermolysis crude oil, and the conversion of 540 °C+ fractions with simulated distillation analysis was in the range of 10–20 % at 410 °C. The hydrotreating results showed that the activation of iron and molybdenum catalysts reduced the viscosity and increased the conversion of the 540 °C+ fraction by about 80 % and 30 %. Simulated distillation findings indicate that the conversion of heavy fractions contributes to the formation of lighter fractions such as naphtha, distillates, and VGO. As a result, the generation of these lighter fractions leads to viscosity reduction. • Crude oils from catalytic and non-catalytic aquathermolysis undergo hydrotreatment. • Up to 90 % viscosity reduction in catalytically treated crude oils. • Improved heavy fraction conversion at higher temperatures during hydrotreatment. • Temperature and catalysts' type and concentration influence final crude properties. [ABSTRACT FROM AUTHOR]