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Insect gustatory system plays important roles in multiple behaviors including feeding, mating, and oviposition. Gustatory receptors (GRs), located on the dendritic membrane of gustatory sensory neurons (GSNs), are crucial in peripheral coding of non-volatile compounds. However, GRs and their detailed functions remain poorly understood in lepidopteran pests. In the present work, focusing on GR genes of Plutella xylostella, an important worldwide crop pest, we cloned a candidate fructose GR gene that has two spliced variants (PxylGR43a-1 and PxylGR43a-2), and determined the tissue expression profiles by semi-quantitative reverse transcription PCR (RT-PCR). It revealed that both GR variants were highly expressed in antennae and less highly in heads of adults, while PxylGR43a-2 was also weakly expressed in other tested tissues. Functional analyses were further conducted using the Xenopus oocyte system. PxylGR43a-1 and PxylGR43a-2 both responded specifically to the d-fructose among the 12 tested sugar compounds, but PxylGR43a-2 showed much higher current response than PxylGR43a-1. In addition, the proboscis extension reflex (PER) assay was conducted, demonstrating that female moths could respond to d-fructose following stimulation of antenna. Taken together, our study contributes to elucidation of the molecular mechanisms of fructose reception and provides a potential target for development of GR based pest control techniques.

Sex pheromones are crucial for communication between females and males in moths, and pheromone receptors (PRs) play a key role in peripheral coding of sex pheromones. During the last decade, many PR candidates have been identified based on transcriptome sequencing and bioinformatic analysis, but their detailed functions remain mostly unknown. Here, focusing on four PR candidates of Athetis dissimilis (AdisOR1, AdisOR6, AdisOR11 and AdisOR14) identified in a previous study, we first cloned the full-length cDNAs and determined the tissue expression profiles by quantitative real-time PCR (qPCR). The results revealed that expression of three of these genes were male antennae-specific, while AdisOR11 was similar in expression between male and female antennae. Furthermore, the expression level of AdisOR1 was much higher than those of the other three genes. Then, functional analysis was conducted using Xenopus oocyte system. AdisOR1 responded strongly to the sex pheromone component Z9–14:OH and the potential pheromone component Z9,E12–14:OH, suggesting its important role in the sex pheromone perception; AdisOR14 showed specificity for Z9,E12–14:OH; while AdisOR6 and AdisOR11 did not respond to any of the pheromone components and analogs tested. Taken together, this study contributes to elucidate the molecular mechanism of sex pheromone reception and provides potential targets for development of OR based pest control techniques in A. dissimilis.

The open-loop albumin dialysis mode (OLM) is usually used to remove protein-bound toxins from artificial liver support systems. However, there is still interest in closed-loop albumin dialysis mode (CLM) because this mode could enable the regeneration and reuse of albumin and minimize the physical size of liver support systems. In this paper, the two dialysis modes were theoretically compared under various theoretical conditions. Our results show that at the beginning of the dialysis period, in terms of detoxification efficiency, CLM is better. As the molar ratio of toxin to albumin in the blood (RTA) decreases, the overall performance of CLM approaches that of OLM in 4-hour dialysis. In certain cases, the clearance of albumin-bound toxins by CLM could be as effective as that by OLM; occasionally, CLM is even more effective.

Adsorption performances of activated carbon Norit RO 0.8, neutral resin Amberlite XAD-7, anion resin Dowex 1x4 and cation resin Dowex 50wx4 were investigated in detail for artificial liver support devices. Firstly, equilibrium adsorption experiments of these adsorbents to albumin, creatinine, bilirubin, tryptophan and cholic acid were conducted respectively. Then their adsorption capacities were obtained by curve fitting. The results indicate that activated carbon Norit RO 0.8 and anion resin Dowex 1x4 are two better adsorbents for removing toxins. Lastly, adsorption rate constants of activated carbon Norit RO 0.8 and anion resin Dowex 1x4 to all above solutes were studied with pseudo-first and second-order kinetic adsorption models. The results show that the toxin adsorption rate of anion resin Dowex 1x4 is faster than that of activated carbon Norit RO 0.8. The systematical experimental results in this paper are very important references for researchers in the field of blood purification based on adsorption technology.