[Ecological Risk and Health Risk of Heavy Metal Pollution in Vegetable Production System of Zhejiang Province].

In order to understand the heavy metal contamination of soil and vegetables in the vegetable production system of Zhejiang Province and the health risks of vegetables consumed by residents, typical vegetable production bases in Zhejiang Province were selected as the study areas; 102 pairs of vegetable and soil samples were collected; the distribution characteristics of heavy metals Cd, Cu, Pb, Cr, As, Ni, and Hg in the vegetable production system of Zhejiang Province were analyzed, and the ecological health risks of the vegetable production system were systematically evaluated using the Nemerow composite pollution index, potential ecological risk index, and dietary exposure assessment model. The results showed that Cd in the soil seriously exceeded the standard, with an exceedance rate of 97.2%. The main risk of soil pollution was moderate and mild, and the highest risk was Cd, followed by Pb, Cu, and As. Among vegetables, only a small amount of bean and fruit vegetables exceeded the Cd content, with the exceedance rates of 12.5% and 8.7%, respectively. The BCF of different types of vegetables differed significantly and could be ranked accordingly:leafy vegetables>bean vegetables>melon vegetables>root vegetables. The non-carcinogenic and carcinogenic risks of Zhejiang residents consuming local vegetables were within acceptable limits, with children being more at risk than adults (P<0.01), and Cd and Pb contributing the most to health risks. The overall vegetables produced by the vegetable production system in Zhejiang Province were at a safe level, but there is a need to strengthen the control of Cd and Pb pollution sources.

Residual behavior and risk assessment of prochloraz in bayberries and bayberry wine for the Chinese population.

The bayberry is an important economic fruit as well as a minor crop in China, and few pesticide products are registered for bayberry. Prochloraz is a widely used fungicide with a high detection rate on bayberry. This study evaluated the potential dietary risk of prochloraz for different populations in China based on field trial data and market surveillance. The results indicate that one-time applications at dosages of 1000 and 1500 mg/kg with a recommended preharvest interval of 20 days do not pose a chronic or acute dietary risk. However, applying the above dosages twice will cause a potential short-term dietary risk. Risk assessment results conducted on surveillance samples indicated acceptable long-term risks for the general population, with a hazard quotient < 0.82. Furthermore, simulated washing and wine production processes were performed to mimic household practices to investigate residue transfer and distribution. We found that rinsing with tap water for 1 min was an effective way to remove residue, and the processing factors of prochloraz for both bayberry and wine were < 1, indicating that wine production could reduce residue levels. Prochloraz had a strong capacity to transfer to wine due to its high log Kow value, with transfer percentages up to 43%. This study supports the recommendation on good agricultural practices for prochloraz application and provides a guide for safe consumption.

[RNAi-mediated Silencing of CXCR4 Inhibits the Adhesion, Invasion and Tumorigenicity of Acute Monocytic Leukemic Cell Line SHI-1].

OBJECTIVE: To investigate the effect of CXCR4 gene on the proliferation, adhesion, invasion and tumorigenicity of a human monocytic leukemic cell line SHI-1. METHODS: The lentivirus vector silencing the expression of CXCR4 was constructed for infection of SHI-1 cells silencing expression of CXCR4 in SHI-1 cells. The expression of CXCR4, MMP-2 and MMP-9 was detected by real time PCR. The expression of CXCR4 on membrane of SHI-1 cells was detected by flow cytometry. The SHI-1 cell proliferation ability was detected by MTT. The co-culture system of the leukemia cells and bone marrow stromal cells was used to detect the adhesion and migration ability of leukemia cells. SHI-1 cells were inoculated subcutaneously in nude mice to investigate the growth ability in vivo. RESULTS: After SHI-1 cells were infected by lentivirus silencing expression of CXCR4, the expression of CXCR4 mRNA in SHI-1 CXCR-4i cells decreased by 76% as compared with expression of SHI-1/NC of negative control virus, the expression of CXCR4 on membrane of SHI-1/CXCR4i obviously downregulated; the expression of MMP-2 and MMP-9 in SHI-1/CXCRi cells also declined by 63% and 62% respectively; the proliferation ability of SHI-1/CXCR4i in vitro did not obviously changed, but the adhesion and trans-matrigel invasion ability significantly decreased, the SHI-1/CXCR4i cells could not form neoplasm subcutaneously in mice, but the SHI-1 and SHI-1/NC cells could form neoplasm subcutaneously in mice, and there was no significant difference in volumn of neoplasm mass. CONCLUSION: The silencing expression of CXCR4 can decline the adhesion and migration ability of SHI-1 cells, and can completely suppress the formation of neoplasm subcutaneously, so the CXCR4 may serve as a target for treating leukemia.

Applications of ultra-performance liquid chromatography to traditional Chinese medicines.

Ultra-performance liquid chromatography (UPLC), as a development of the chromatographic technique, was used in the quality control of Panax ginseng C.A. Mey. In the study, the UPLC methods were transferred from conventional high-performance liquid chromatography (HPLC) methods according to chromatographic equations. The results demonstrated that UPLC analysis methods could be transferred from HPLC without loss of efficiency. Compared with conventional HPLC, UPLC made a surprising 10-fold increase in speed and 20-fold decrease in solvent consumption. The study indicated UPLC as a suitable alternative to HPLC and can be reliably applied to quality control of traditional Chinese medicines.