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There is an ongoing debate about the benefit of fresh frozen plasma (FFP) infusion in organophosphorus (OP) pesticide-poisoned patients. This prompted us to investigate the kinetics of OP pesticide degradation by FFP with an enzymatic assay in vitro . Degradation was rapid with shortest half-lives of 19.5 s for chlorpyrifos-oxon, 6.3 min for paraoxon-ethyl and 17.9 min for dichlorvos. Heptenophos (78.0 min), mevinphos (101.8 min), profenofos (162.3 min) and malaoxon (179.7 min) showed half-lives of up to 3 h. Substantial longer degradation half-lives of 69.7–80.8 h were determined with chlorfenvinphos and bromfenvinphos. Methamidophos and omethoate showed no degradation by FFP indicated by half-lives similar to spontaneous hydrolysis. In conclusion, degradation by FFP depends on the particular OP pesticide and the used FFP batch. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this work was to study the in vitro replication of bovine herpesvirus types 1 and 5 (BoHV-1 and 5) at the beginning and end of the logarithmic growth phase of Madin-Darby Bovine Kidney (MDBK) cells. The replication kinetics and size of lysis and infection plaques of the field isolates 09/210 (BoHV-1) and 97/613 (BoHV-5) and the reference strains BoHV-1.1 Los Angeles 38 (LA38), BoHV-1.1 Cooper, BoHV-5a N569 and BoHV-5b A663 were evaluated. The highest mean virus titre was recorded for N569, followed by LA38 and 97/613. For most of the viruses, the virus titre values increased from 24h post-infection (hpi) up to 48hpi and then, they remained unchanged up to 72hpi. However, the virus titre for 09/210 was significantly lower and a slight, steady increase was observed from 24 to 72hpi. Furthermore, the largest lysis and infection plaques were recorded for 97/613 and LA38, respectively. According to this work, it is evident that there is a relationship between the replication of BoHV and the multiplication stage of MDBK cells. The results of this study contribute to the understanding of the replication behaviour in cell cultures of several strains of BoHV, which is critical for the rational design of in vitro experiments and vaccine production. [Copyright &y& Elsevier]

Abstract: The simultaneous use of the repellent DEET, pyridostigmine, and organophosphorus pesticides has been assumed as a potential cause for the Gulf War Illness and combinations have been tested in different animal models. However, human in vitro data on interactions of DEET with other compounds are scarce and provoked the present in vitro study scrutinizing the interactions of DEET, pyridostigmine and pesticides with human acetylcholinesterase (hAChE) and butyrylcholinesterase (hBChE). DEET showed to be a weak and reversible inhibitor of hAChE and hBChE. The IC50 of DEET was calculated to be 21.7mM DEET for hAChE and 3.2mM DEET for hBChE. The determination of the inhibition kinetics of pyridostigmine, malaoxon and chlorpyrifos oxon with hAChE in the presence of 5mM DEET resulted in a moderate reduction of the inhibition rate constant k i. The decarbamoylation velocity of pyridostigmine-inhibited hAChE was not affected by DEET. In conclusion, the in vitro investigation of interactions between human cholinesterases, DEET, pyridostigmine, malaoxon and chlorpyrifos oxon showed a weak inhibition of hAChE and hBChE by DEET. The inhibitory potency of the tested cholinesterase inhibitors was not enhanced by DEET and it did not affect the regeneration velocity of pyridostigmine-inhibited AChE. Hence, this in vitro study does not give any evidence of a synergistic effect of the tested compounds on human cholinesterases. [Copyright &y& Elsevier]

Abstract: In this study, doxorubicin (DOX) was physically incorporated into pH-sensitive micelles made from a mixture of poly(l -histidine)-b-poly(ethylene glycol)/poly(l -lactide)-b-poly(ethylene glycol) (75/25, wt.%). The DOX-loaded mixed micelles were formulated using dialysis methods and optimal DOX incorporation was achieved at a drug/polymer feed ratio of 0.2 (wt./wt.) when a proper amount of aqueous phase (0.2, v./v.) was added into the common solvent (DMSO) solution, followed by dialysis at 4°C. Based on the results obtained from dynamic light scattering, UV–Vis absorption, and fluorescence experiments, it was demonstrated that the encapsulated drugs were mainly located inside the hydrophobic micelle cores, well protected and inaccessible to the exterior molecules. Under in vitro conditions, although the microstructure of the micelles was altered below pH 8.0 by the encapsulated drugs, the drug-loaded micelles still exhibited a desirable ability to control the drug release in response to tumor extracellular pH. [Copyright &y& Elsevier]