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Weak and small honey bee colonies are supposed to be more susceptible to infestations by the small hive beetle [ Aethina tumida, small hive beetle ( SHB)]. To test this, we established 24 nucleus colonies [12 with and 12 without previous SHB removal (= screening)]. Four weeks later, we compared beetle numbers and the occurrence of SHB reproduction to the corresponding full-sized colonies. Full-sized colonies with no screening were infested with significantly more SHBs than all other groups (mean ± standard deviation = 46.9 ± 26.7). Regardless of this, none of the full-sized colonies showed damage or evidence of SHB reproduction. In contrast, five nucleus colonies collapsed and SHB larvae were found in an additional seven colonies. Our study demonstrates that SHB infestation levels which are harmless to full-sized colonies may have a negative impact on small nucleus colonies. [ABSTRACT FROM AUTHOR]

The efficiency of kinase inhibiting cancer therapeutics is often limited by their poor solubility in water. PEGylation is one possible strategy to improve the solubility of the drug, however, means to cleave these after reaching the target is important to make use of the therapeutic effects of the native drug. Moreover, the length of the PEG chains will have an effect on the solubility and binding. In this study we want to extend our understanding of solubilizing oligo ethylene glycol (OEG) chains connected to kinase inhibitors using a pH labile phosphoramidate linker.  We synthesize a library of drug-OEG conjugates for Ceritinib, Crizotinib, Palbociclib, and Ribocilib kinase inhibitors with n = 2, 3, 4 and 8 OEG repeat units. We study the influence on water solubility, enzyme inhibition, and pH induced hydrolysis. A maximum in solubility is obtained for n = 3 or 4. We show that small differences in chain length can strongly influence the water solubility while all other properties remain relatively comparable., (© 2025 Wiley‐VCH GmbH.)

Small molecular kinase inhibitors play a key role in modern cancer therapy. Protein kinases are essential mediators in the growth and progression of cancerous tumors, rendering involved kinases an increasingly important target for therapy. However, kinase inhibitors are almost insoluble in water because of their hydrophobic aromatic nature, often lowering their availability and pharmacological efficacy. Direct drug functionalization with polar groups represents a simple strategy to improve the drug solubility, availability, and performance. Here, we present a strategy to functionalize secondary amines with oligoethylene glycol (OEG) phosphate using a one-pot synthesis in three exemplary kinase inhibiting drugs Ceritinib, Crizotinib, and Palbociclib. These OEG-prodrug conjugates demonstrate superior solubility in water compared to the native drugs, with the solubility increasing up to 190-fold. The kinase inhibition potential is only slightly decreased for the conjugates compared to the native drugs. We further show pH dependent hydrolysis of the OEG-prodrugs which releases the native drug. We observe a slow release at pH 3, while the conjugates remain stable over 96 h under physiological conditions (pH 7.4). Using confocal microscopy, we verify improved cell uptake of the drug-OEG conjugates into the cytoplasm of HeLa cells, further supporting our universal solubility approach., (© 2024 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

Although the principal mechanisms of insect flight are well understood, knowledge about the influence of environmental factors on flight performance is scarce. We show that ambient temperature (TA) and illuminance have an influence on the flight performance of hornets. Moreover, the regulation of flight speed at different environmental conditions is sex specific. In roundabout experiments with tethered hornets, the flight speed of workers was independent of TA, while that of drones was negatively correlated with TA. We hypothesize that the reasons for these differences may lie in sex-specific cooling mechanisms; workers might regulate their body temperature through forced heat loss, whereas drones might reduce their heat production rates. At low illuminance, workers reduced their flight speed, whereas drones did not. Reduced flight speed at low illuminances is probably a behavioral mechanism of compensation for disadvantages caused by changing neuronal processes in the sensory neurons in darkness.