High γ-aminobutyric acid content, a novel component associated with resistance to abamectin in Tetranychus cinnabarinus (Boisduval).

An abamectin-resistant strain of Tetranychus cinnabarinus (Boisduval) (Rf=25.3) was selected in laboratory. We compared the γ-aminobutyric acid (GABA) content in abamectin-susceptible T. cinnabarinus individuals with that in resistant individuals and investigated its relationship to abamectin resistance. High performance liquid chromatography (HPLC) was used to ascertain GABA content in abamectin-susceptible (SS) and resistant (AR) strains of T. cinnabarinus. The results indicate that GABA content in the AR was significantly higher than that in the SS (1.39-fold). AR individuals treated with a sublethal dose of abamectin did not show significant differences in GABA levels compared with AR individuals that were not treated with abamectin. However in the SS, abamectin treated individuals had a significantly higher GABA content than those that were untreated (1.52-fold). Individuals in the SS that survived from selection with LC(95) of abamectin (SS-AR) showed significantly higher GABA levels compared to SS (1.41-fold). Similarly, progenies of the SS-AR parental generation (SS-ARF(1)) also showed increased GABA levels (1.51-fold) compared to SS. In addition, behavioral observations have shown that all individuals from the AR, SS-AR and SS-ARF(1), which had more GABA content than the SS, demonstrated a significant decrease in crawling speed compared with SS individuals. This observation is consistent with excessive GABA levels had inhibitory effect on the central nervous system. Thus, we postulate that increasing GABA content in T. cinnabarinus is associated with resistance against abamectin.

Research evolvement of postmortem diagnosis of early myocardial infarction in forensic pathology / 法医学杂志

The cardiac sudden death occupies primacy among the cause of death in adult. Myocardial infarction is one of the main mechanisms of sudden death of coronary heart disease. Because of early myocardial infarction happened abruptly and might die in a short time, and the typical or special changes in morphology is absent, so it is the focus of medico legal research forensic fulfill all long. This paper reviewed the characters of myocardial infarction, applications and limits in forensic fields, and prospected feasibility of new clinical markers in forensic practice, and expected to enhance accuracy of postmortem diagnosis in MI.