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Aedes aegypti is an anautogenous mosquito that must blood feed on a vertebrate host to produce and lay a clutch of eggs. The rockpool mosquito, Georgecraigius atropalpus , is related to A. aegypti but is a facultatively autogenous species that produces its first clutch of eggs shortly after emerging without blood feeding. Consumption of a blood meal by A. aegypti triggers the release of ovary ecdysteroidogenic hormone (OEH) and insulin-like peptide 3 (ILP3) from the brain, which stimulate egg formation . OEH and ILP3 also stimulate egg formation in G. atropalpus but are released at eclosion independently of blood feeding. These results collectively suggest that blood meal dependent release of OEH and ILP3 is one factor that prevents A. aegypti from reproducing autogenously. Here, we examined two other factors that potentially inhibit autogeny in A. aegypti : teneral nutrient reserves and the ability of OEH and ILP3 to stimulate egg formation in the absence of blood feeding. Measures of nutrient reserves showed that newly emerged A. aegypti females had similar wet weights but significantly lower protein and glycogen reserves than G. atropalpus females when larvae were reared under identical conditions. OEH stimulated non-blood fed A. aegypti females to produce ecdysteroid hormone and package yolk into oocytes more strongly than ILP3. OEH also reduced host seeking and blood feeding behavior, yet females produced few mature eggs. Overall, our results indicate that multiple factors prevent A. aegypti from reproducing autogenously. [ABSTRACT FROM AUTHOR]

HIV-associated wasting, characterized by progressive loss of lean body mass and bodyweight, remains a significant problem in the era of highly active antiretroviral therapy. Loss of body cell mass, a component of lean body mass, is associated with decreased survival. Somatropin (recombinant human growth hormone) derived from mammalian cells (Serostim) is the only US FDA-approved treatment indicated to increase lean body mass, bodyweight, and physical endurance in HIV-associated wasting.Somatropin 0.1 mg/kg/day administered subcutaneously for 12 weeks effectively increased work output, bodyweight, and lean body mass, and improved health-related quality of life, compared with placebo, and had a generally manageable tolerability profile in a large randomized study in patients with HIV-associated wasting.Potential areas for further research include determination of longer-term efficacy and tolerability, the cost effectiveness of treatment, the optimal somatropin dosage, management of patients after 12 weeksʼ therapy, and whether maintenance strategies might exist to maintain accrued lean body mass with lower doses of somatropin. Nevertheless, indications to date are that somatropin is likely to have an important role in the treatment of patients with HIV-associated wasting. [ABSTRACT FROM AUTHOR]