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Objective: Although inferior vena cava (IVC) filters are commonly retrieved using a snare, lateral tilt and fibrosis around struts can complicate the procedure and sometimes require the use of off-label devices. We describe the development of a novel articulating endovascular grasper designed to remove permanent and retrievable IVC filters in any configuration., Methods: For in vitro testing, the IVC filters were anchored to the inner wall of a flexible tube in a centered or tilted configuration. A high-contrast backlit camera view simulated the two-dimensional fluoroscopy projection during retrieval. The time from the retrieval device introduction into the camera field to complete filter retrieval was measured in seconds. The control experiment involved temporary IVC filter retrieval with a snare. There were four comparative groups: (1) retrievable filter in centered configuration; (2) retrievable filter in tilted configuration; (3) permanent filter in centered configuration; and (4) permanent filter in tilted configuration. Every experiment was repeated five times, with median retrieval time compared with the control group. For in vivo testing in a porcine model, six tilted infrarenal IVC filters were retrieved with grasper via right jugular approach. Comparison analysis between animal and patient procedures was performed for the following variables: total procedure time, the retrieval time, and fluoroscopy time., Results: The in vitro experiments showed comparable retrieval times between the experimental groups 1, 2, and 4 and the control. However, grasper removal of a centered permanent filter (group 3) required significantly less time than in the control (29 vs 79 seconds; P = .009). In the animal model, all IVC filters were retrieved using the grasper with no adverse events. The total procedure time (21.2 vs 43.5 minutes; P = .01) and the fluoroscopy time (4.3 vs 10 minutes; P = .044) were significantly shorter in the animal model compared with the patient group. Moreover, in the patient group, 16.7% of retrievals required advanced endovascular techniques, and one IVC filter could not be retrieved (success rate = 91.7%), whereas all the IVC filters were successfully retrieved in the animal model without the use of additional tools., Conclusions: The novel endovascular grasper is effective in retrieving different types of IVC filters in different configurations and compared favorably with the snare in the in vitro model. In vivo experiments demonstrated more effective retrieval when compared with matched patient retrievals., Competing Interests: Disclosures None., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

The monoterpene camphor is produced in glandular secretory trichomes of the medicinal plant Artemisia annua , which also produces the antimalarial drug artemisinin. We have found that, depending on growth conditions, camphor can accumulate at levels ranging from 1- 10% leaf dry weight (LDW) in the Artemis F1 hybrid, which has been developed for commercial production of artemisinin at up to 1% LDW. We discovered that a camphor null (camphor-0) phenotype segregates in the progeny of self-pollinated Artemis material. Camphor-0 plants also show reduced levels of other less abundant monoterpenes and increased levels of the sesquiterpene precursor farnesyl pyrophosphate plus sesquiterpenes, including enzymatically derived artemisinin pathway intermediates but not artemisinin. One possible explanation for this is that high camphor concentrations in the glandular secretory trichomes play an important role in generating the hydrophobic conditions required for the non-enzymatic conversion of dihydroartemisinic acid tertiary hydroperoxide to artemisinin. We established that the camphor-0 phenotype associates with a genomic deletion that results in loss of a Bornyl diPhosphate Synthase ( AaBPS ) gene candidate. Functional characterization of the corresponding enzyme in vitro confirmed it can catalyze the first committed step in not only camphor biosynthesis but also in a number of other monoterpenes, accounting for over 60% of total volatiles in A. annua leaves. This in vitro analysis is consistent with loss of monoterpenes in camphor-0 plants. The AaBPS promoter drives high reporter gene expression in A. annua glandular secretory trichomes of juvenile leaves with expression shifting to non-glandular trichomes in mature leaves, which is consistent with AaBPS transcript abundance., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Czechowski, Branigan, Rae, Rathbone, Larson, Harvey, Catania, Zhang, Li, Salmon, Bowles, O´Maille and Graham.)

In recent years, rabies virus-derived peptide (RDP) has shown promise as a specific neural cell targeting ligand, however stability of the peptide in human serum was unknown. Herein, we report the molecular modelling and design of an optimised peptide sequence based on interactions of RDP with the α7 subunit of the nicotinic acetylcholine receptor (nAChR). The new sequence, named DAS, designed around a 5-mer sequence which demonstrated optimal nAChR binding in silico , showed greatly improved stability for up to 8 hours in human serum in comparison to RDP, which degraded within 2 hours at 37 °C. In vitro analysis using SH-SY5Y neuroblastoma cells showed that DAS-conjugated nanoparticles containing the cytotoxic drug doxorubicin (DAS-Dox-NP) displayed significantly enhanced cytotoxicity compared with untargeted doxorubicin-loaded nanoparticles (Dox-NP). DAS-Dox-NP had no significant effect on non-neural cell types, confirming its neural-specific targeting properties. In this manuscript, we report the design and testing of an optimised peptide ligand, conjugated to a nanoparticulate delivery vehicle and specifically targeted to neural cells. Future impact of an innovative targeting peptide ligand combining the ability to selectively identify the target and facilitate cellular internalisation could enable the successful treatment of many neural cell disorders.