Early plasma exchange for treating ricin toxicity in children after castor bean ingestion.

Plasma exchange (PE) for the treatment of ricin toxicity has not been previously reported. Here we describe the use of PE to treat children who experienced ricin toxicity after ingesting castor beans. Seven children (median age: 8.1 years) who consumed castor beans (median: 5 beans) were treated with PE. All had bradycardia and sinus arrhythmia, and most had experienced episodes of vomiting and/or diarrhea. PE settings were blood flow, 50-80 mL/min; PE rate, 600-800 mL/h; volume of exchange, 1440-1950 mL. Median time from ingestion to PE was 73 h. All clinical symptoms disappeared and vital signs rapidly returned to normal after PE; no severe organ dysfunction occurred. All children were discharged and recovered uneventfully. Concentrations of all serum biochemical parameters significantly decreased immediately after PE. Some, but not all, of these parameters were also significantly decreased at 48 and 72 h after PE compared with before PE. Our findings suggest that PE can be an effective early intervention in the treatment of ricin toxicity due to castor bean ingestion.

Differences between Two Groups of Burmese Vipers (Viperidae: Azemiops) in the Proteomic Profiles, Immunoreactivity and Biochemical Functions of Their Venoms.

Two recently revised Azemiops snakes with apparent differences in their external appearances and skeletal morphologies but unclear genetic boundaries have been proposed. Some researchers have refrained from using the newly proposed taxonomy because these two "species" might be two clades corresponding to different geographical populations of Azemiops feae. To improve the understanding of the kinship of these two Burmese viper groups, more of their characteristics should be explored in depth. We performed a comparative analysis of the proteomic profiles and biochemical activities of snake venoms from these two groups (Sichuan A. feae and Zhejiang A. feae) and evaluated the immunorecognition capacity of commercial antivenoms toward them. Eight protein families were identified in venoms from these two groups, while phospholipase B was only detected in venom from Sichuan A. feae. These protein families displayed varying degrees of differences in relative abundance between venoms, and phospholipase A2 (Sichuan A. feae: 57.15%; Zhejiang A. feae: 65.94%) was the predominated component. Gloydius brevicaudus antivenom exhibited the strongest capacity to immunologically recognize these two venoms, but this was mainly limited to components with high molecular masses, some of which differed between venoms. Additionally, Zhejiang A. feae venom was more toxic than Sichuan A. feae venom, and the venoms expressed remarkable differences in enzymatic activities, probably resulting from the variation in the relative abundance of specific protein families. Our findings unveil differences between the two Burmese viper groups in terms of proteomic profiles, immunoreactivity, and the biochemical functions of their venoms. This information will facilitate the management of snakebites caused by these snakes.

[Stability characteristics of soil organic carbon pool following development of sand-fixing forest in Mu Us sandy land, China]. / æ¯›ä¹Œç´ æ²™åœ°å›ºæ²™æž—å‘è‚²è¿‡ç¨‹ä¸­åœŸå£¤æœ‰æœºç¢³åº“ç¨³å®šæ€§ç‰¹å¾.

The study aimed to reveal the cumulative effects and stability characteristics of soil organic carbon (SOC) during forest development at the Mu Us sandy land, China. Using space for time substitution, surface soil samples were collected from semi-fixed sandy lands and restored arbor and shrub lands with the ages of 22, 32 and 53 years in the Yulin sand control region in Northern Shaanxi Province. The content of total organic carbon (TOC), oxidizable labile organic carbon, and resistant carbon and the characteristics of mineralized carbon emission and decomposition ratio were analyzed. The results showed that the increment of TOC for 22 to 53 years shrub and arbor lands from resistant carbon were 3.5-6.2 g·kg-1 and 3.2-7.7 g·kg-1, and from oxidized labile carbon were 2.8-3.4 g·kg-1 and 1.3-2.8 g·kg-1, respectively, compared with semi-fixed sand land. The ratio of soil oxidizable labile carbon in shrub land and arbor land were stable and maintained at 37.0% and 26.8%, respectively. However, the ratio decreased to 25.7% and 17.4% after incubated at a constant temperature for 60 days. The mineralization rate of shrub and arbor lands with 22-53 years was not significant at the ending of soil incubation. Carbon losses from oxidized liable carbon were 76.9%-98.7%, and only 1.3%-23.5% from resistant carbon in all sand-fixing forest plots. Compared with the maximum carbon emission rate, the soil cumulative carbon release exhibited a higher correlation with soil enzyme activities of ß-glucosidase and dehydrogenase, but the enzyme activities did not change from 32-53 years. In conclusion, SOC pool showed stable characteristics of lower emission and higher sequestration with the increases of sand-fixing forest stand age. The carbon fixation effect of arbor sand-fixing forest was better than that of shrub sand-fixing forest.

[Species sensitive distribution for aquatic biota exposed to triazophos].

The increasing pollution of organophosphorus pesticides (OP) in water have been of concerns. Taking the widely used triazophos as the object, a species sensitivity distribution (SSD) model was developed using a log-logistic distribution based on the median effective concentrations (EC50) of triazophos to aquatic species at various trophic levels, and then the model was tested and evaluated using probability plots and good-of-fit tests. The results showed that the SSD for aquatic biota exposed to triazophos was well fitted by a log-logistic distribution, which was totally determined by the two parameters, alpha = -0.4788 and beta = 0.7546, with standard error 0.2381 and 0.1078 respectively. Based on the SSD model, the hazardous concentration for 5% of the species (HC5) and the criteria maximum concentration (CMC) of triazophos were 1.992 x 10(-3) mg/L and 9.96 x 10(-4) mg/L, respectively. Through comparing the HC5 and CMC with the safe concentration for single-species, it could be found that environmental quality criteria derived from the SSD model was more strict, and closed to the real ecological environment. In addition, according to the reported data, the potentially affected fraction (PAF) of species exposed to triazophos in the Laizhou Bay (Bohai Sea, China) area was 0.36% predicted by the SSD model, and the corresponding risk might not be significant.