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2.
IEEE Trans Biomed Eng ; 66(6): 1723-1729, 2019 06.
Article in English | MEDLINE | ID: mdl-30387716

ABSTRACT

OBJECTIVE: The goal of this study was to demonstrate the technical feasibility of automated balloon pressure management during resuscitative endovascular balloon occlusion of the aorta (REBOA) in the pre-clinical setting. METHODS: This paper presents an intelligent balloon management device which automates the balloon inflation process, preventing the possibility of balloon over or under inflation, optimizes inflation pressure, and if indicated, deflates automating partial REBOA to allow the distal organ perfusion. Edwards TruWave pressure transducers are used to monitor the blood pressure proximal and distal to the balloon, as well as the internal balloon pressure. A faux PID controller, implemented on an Arduino platform, is used in a feedback control loop to allow a user-defined mean arterial pressure setpoint to be reached, via a syringe driver which allows intelligent inflation and deflation of the catheter balloon. RESULTS: Ex vivo testing on a vascular perfusion simulator provided the characteristic behavior of a fully occluded aorta, namely the decrease of distal pressure to zero. In vivo testing on live porcine models indicated that automated partial REBOA is achievable and by enabling partial occlusion may offer improved medical outcomes compared to the manual control. CONCLUSION: Automated balloon pressure management of endovascular occlusion is feasible and can be successfully implemented without changes on current clinical workflows. SIGNIFICANCE: With further development, automated balloon management may significantly improve clinical outcomes in REBOA.


Subject(s)
Aorta/surgery , Balloon Occlusion , Endovascular Procedures , Resuscitation/instrumentation , Animals , Automation/instrumentation , Balloon Occlusion/instrumentation , Balloon Occlusion/methods , Blood Pressure/physiology , Critical Care , Disease Models, Animal , Endovascular Procedures/instrumentation , Endovascular Procedures/methods , Equipment Design , Feedback , Female , Hemorrhage/surgery , Humans , Models, Cardiovascular , Swine
3.
Org Biomol Chem ; 16(15): 2647-2665, 2018 04 18.
Article in English | MEDLINE | ID: mdl-29542786

ABSTRACT

Malaria is a tropical parasitic disease threatening populations in tropical and sub-tropical areas. Resistance to antimalarial drugs has spread all over the world in the past 50 years, thus new drugs are urgently needed. Plasmodione (benzylmenadione series) has been identified as a potent antimalarial early lead drug, acting through a redox bioactivation on asexual and young sexual blood stages. To investigate its metabolism, a series of plasmodione-based tools, including a fully 13C-labelled lead drug and putative metabolites, have been designed and synthesized for drug metabolism investigation. Furthermore, with the help of UHPLC-MS/MS, two of the drug metabolites have been identified from urine of drug-treated mice.


Subject(s)
Antimalarials/chemical synthesis , Vitamin K 3/analogs & derivatives , Vitamin K 3/chemical synthesis , Animals , Antimalarials/metabolism , Antimalarials/pharmacology , Carbon Isotopes , Drug Resistance, Multiple , Humans , Isotope Labeling , Mice , Oxidation-Reduction , Plasmodium berghei/drug effects , Plasmodium falciparum/drug effects , Vitamin K 3/metabolism , Vitamin K 3/pharmacology
4.
Nat Commun ; 8: 14478, 2017 02 17.
Article in English | MEDLINE | ID: mdl-28211535

ABSTRACT

In search of antiparasitic agents, we here identify arylmethylamino steroids as potent compounds and characterize more than 60 derivatives. The lead compound 1o is fast acting and highly active against intraerythrocytic stages of chloroquine-sensitive and resistant Plasmodium falciparum parasites (IC50 1-5 nM) as well as against gametocytes. In P. berghei-infected mice, oral administration of 1o drastically reduces parasitaemia and cures the animals. Furthermore, 1o efficiently blocks parasite transmission from mice to mosquitoes. The steroid compounds show low cytotoxicity in mammalian cells and do not induce acute toxicity symptoms in mice. Moreover, 1o has a remarkable activity against the blood-feeding trematode parasite Schistosoma mansoni. The steroid and the hydroxyarylmethylamino moieties are essential for antimalarial activity supporting a chelate-based quinone methide mechanism involving metal or haem bioactivation. This study identifies chemical scaffolds that are rapidly internalized into blood-feeding parasites.


Subject(s)
Amines/pharmacology , Antiparasitic Agents/pharmacology , Steroids/pharmacology , Amines/chemistry , Amines/pharmacokinetics , Animals , Anopheles/parasitology , Anti-Infective Agents/pharmacology , Antiparasitic Agents/chemistry , Antiparasitic Agents/pharmacokinetics , Cell Death/drug effects , Cell Proliferation/drug effects , Female , Germ Cells/drug effects , Inhibitory Concentration 50 , Life Cycle Stages/drug effects , Malaria/parasitology , Malaria/transmission , Mice , Models, Biological , Parasites/drug effects , Plasmodium berghei/drug effects , Plasmodium berghei/growth & development , Plasmodium falciparum/drug effects , Plasmodium falciparum/growth & development , Schistosoma mansoni/drug effects , Schistosoma mansoni/ultrastructure , Steroids/chemistry , Steroids/pharmacokinetics , Toxicity Tests, Acute
5.
Antimicrob Agents Chemother ; 60(9): 5146-58, 2016 09.
Article in English | MEDLINE | ID: mdl-27297478

ABSTRACT

Previously, we presented the chemical design of a promising series of antimalarial agents, 3-[substituted-benzyl]-menadiones, with potent in vitro and in vivo activities. Ongoing studies on the mode of action of antimalarial 3-[substituted-benzyl]-menadiones revealed that these agents disturb the redox balance of the parasitized erythrocyte by acting as redox cyclers-a strategy that is broadly recognized for the development of new antimalarial agents. Here we report a detailed parasitological characterization of the in vitro activity profile of the lead compound 3-[4-(trifluoromethyl)benzyl]-menadione 1c (henceforth called plasmodione) against intraerythrocytic stages of the human malaria parasite Plasmodium falciparum We show that plasmodione acts rapidly against asexual blood stages, thereby disrupting the clinically relevant intraerythrocytic life cycle of the parasite, and furthermore has potent activity against early gametocytes. The lead's antiplasmodial activity was unaffected by the most common mechanisms of resistance to clinically used antimalarials. Moreover, plasmodione has a low potential to induce drug resistance and a high killing speed, as observed by culturing parasites under continuous drug pressure. Drug interactions with licensed antimalarial drugs were also established using the fixed-ratio isobologram method. Initial toxicological profiling suggests that plasmodione is a safe agent for possible human use. Our studies identify plasmodione as a promising antimalarial lead compound and strongly support the future development of redox-active benzylmenadiones as antimalarial agents.


Subject(s)
Antimalarials/pharmacology , Gametogenesis/drug effects , Life Cycle Stages/drug effects , Naphthoquinones/pharmacology , Plasmodium falciparum/drug effects , Antimalarials/chemical synthesis , Artemisinins/pharmacology , Atovaquone/pharmacology , Drug Interactions , Drug Resistance/drug effects , Erythrocytes/drug effects , Erythrocytes/parasitology , Humans , Inhibitory Concentration 50 , Methylene Blue/pharmacology , Naphthoquinones/chemical synthesis , Plasmodium falciparum/growth & development
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