A k-nearest neighbor (k-NN) classification model was constructed for 118 RDT NEDO (Repeated Dose Toxicity New Energy and industrial technology Development Organization; currently known as the Hazard Evaluation Support System (HESS)) database chemicals, employing two acute toxicity (LD50)-based classes as a response and using a series of eight PaDEL software-derived fingerprints as predictor var...

The virulence of representative strains of the five species of Listeria monocytogenes sensu lato was compared in C57BL/6 and BALB/c mice in terms of LD50 values and of bacterial growth kinetics and histological changes in mouse livers. L. monocytogenes sensu stricto and L. ivanovii showed relatively low LD50 values and much bacterial growth for 2-3 days before viable counts declined. Histologic...

Pharmacological pretreatment and antidotal treatment on tabun-induced neurotoxicity were studied in male albino rats that were poisoned with a lethal dose of tabun (280 microg/kg i.m.; 100% of LD50 value) and observed at 24 hours and 7 days following tabun challenge. The neurotoxicity of tabun was evaluated using a Functional observational battery and an automatic measurement of motor activity....

A series of copolymers is prepared using maleimide and 2-ethylacrylic acid as comonomer. This kind of copolymer shows low toxicity (LD50: 601-798 mg/kg) and significant curative effect on Lewis lung carcinoma and S180.

A study was conducted to determine the release rates of piperonyl butoxide (PBO) and permethrin from synergized insecticidal cattle ear tags and their effects on mortality of the horn fly, Hematobia irritans irritans (L.) (Diptera: Muscidae). PBO was released from the ear tags at a higher rate than permethrin in both winter and summer trials. The cumulative release of PBO and permethrin from th...

A fungal isolate was detected on a dead Triatoma sordida (Stål) collected in a peridomestic area in central Brazil. The fungus belongs to Evlachovaea Borisov and Tarasov, a new genus that was recently described in Russia. The isolate seems to be a third species and the second new and undescribed species fromBrazil. The fungus was shown to be active against Triatoma infestans (Klug) third-instar...

A probabilistic model was developed to estimate target and non-target avian mortality associated with the application of the avicide CPTH (3-chloro-p-toluidine hydrochloride) to minimize sprouting rice damage in the southern USA. CPTH exposures for individual birds were predicted by random sampling from species-specific non-parametric distributions of bait seed consumption and CPTH residues det...

Isobutylene has a low order of acute toxicity. As isobutylene is a gas at normal temperature and pressure, ingestion or dermal absorption of this material is unlikely. The 2-hour LC50 of isobutylene in mice was 180,000 ppm (415 mg/L) and the 4-hour LC50 in rats was 270,000 ppm (620 mg/L). Inhalation of isobutylene can produce central nervous system depression, anesthesia and/or asphyxiation. Ho...

Effect of specific inhibitors of extracellular-signal regulated protein kinase (ERK) pathway, PD98059 and U0126, on P-glycoprotein (Pgp)-mediated vincristine resistance of L1210/VCR cells was investigated. Both test inhibitors significantly reduced the survival of L1210/VCR cells in the presence of vincristine and this was associated with a decrease of LC50 values to vincristine from 2.65+/-0.4...

The essential oil of catnip, Nepeta cataria (Lamiacae) was evaluated for behavioral effects on two populations of subterranean termite, Reticulitermes flavipes (Kollar) and R. virginicus (Banks) (Isoptera: Rhinotermitidae). The catnip essential oil contained approximately 36:64 E,Z-nepetalactone and Z,E-nepetalactone, respectively. The time to 50% dissipation (DT50) of the isomers in sand was d...