The therapy level for TMB-4 was revised based on the approved human dose of 2.56 μmol/kg and converted to 11.8 μmol/kg based on the FDA conversion factor for guinea pigs (4.6 to adjust for body surface area, guinea pig/human, USDHHS, 2005). This

was equivalent to 5.26 mg/kg then multiplied by three autoinjectors (maximum pre-hospital dose) for a final dose of 15.8 mg/kg (35 μmol/kg). HI-6 DMS, MMB4 DMS, RS194B and MINA were evaluated at an additional dose level equal to the median lethal dose (LD50) for the oxime divided by the Therapeutic Index (TI) for 2-PAM Cl (Table 2c). Specifically, TI2-PAM Cl is the ratio of the 24-h LD50 (168 mg/kg; Fleisher et al., 1970) to the FDA-approved human therapeutic dose (i.e., median effective dose, ED50 = 25.7 mg/kg; Koplovitz et al., 1992) or TI2−PAMCl=LD502‐PAMCl,IMinguineapigsED502‐PAMCl,IMinguineapigs=168mg/kg25.7mg/kg=6.53 The TI-based dose level selleck inhibitor for those oximes would be determined selleck compound using the following method TI‐basedDLoxime=LD50,oxime6.53or 15.3% of the LD50,oxime. Clinical observations were recorded for 24 h post challenge by individuals not involved in challenges. Terminal blood samples were collected

and processed for all survivors using Hemoglobind™ (McGarry et al., 2013). For each animal, the relative AChE activity level (RAAChE) was calculated as the Ellman assay acetylthiocholine turnover rate in a terminal blood sample divided by the turnover rate in the baseline blood sample (Ellman et al., 1961). A similar calculation was made using butyrylthiocholine turnover rates to determine RABChE for each surviving guinea pig. Cholinesterase activity was normalized to the individual animal’s baseline to determine RAAChE and RABChE, which were compared using t-tests. A QOL scoring system was

used Erastin in vivo to provide an objective value for the clinical signs observed. Increasing scores were indicative of a decrease in the QOL. QOL scores were calculated with group averages at each time-point. The signs and scores associated with the signs are described in Table 3. For the impaired and mild signs, if any of the listed signs were present for that classification (e.g., ataxic, miosis), then the score for that classification was assigned a value of 1 regardless of the presence/absence of other signs in that classification. Moderate and severe signs were scored individually and not as a group. For any time period in which the animal was still alive to include moribund, the highest score that an animal could attain was 11. If death was recorded at any time-point, the total score for that period was assigned a value of 12. The lower the animal’s QOL score, the closer its exhibited behavior was to that prior to challenge. QOL scores were compared using non parametric Wilcoxon Mann Whitney tests. Fisher’s exact tests at a one-sided α = 0.05 decision level were used to contrast lethality between control and each treatment group.