Pooled analysis of LAMP assay for the diagnosis of norovirus infection.

BACKGROUND: Rapid laboratory detection is essential to diagnose norovirus infection. LAMP has many advantages compared with RT-PCR for detecting norovirus, including high sensitivity, high specificity, rapidity, low cost, and intuitive results, which can be easily read with the naked eye with the help of color-based reporters. In this study, we intend to analyze the accuracy of LAMP methods for the diagnosis of norovirus infection. METHODS: Two researchers independently retrieved relevant literature up to January 2021 (PubMed, Web of Science, Cochrane Library, Embase, CNKI, Wan Fang, and VIP). The researchers screened all articles and extracted their research data for meta-analysis. QUADAS-2 tool was used to evaluate the quality of the included studies by Review Manager 5.3. Forest plots were performed by Meta-DiSc 1.4 to evaluate the accuracy of the test. Deeks' funnel plot symmetry tests were conducted by Stata 15.0 to check the potential publication bias. RESULTS: Eleven sets of data extracted from the eight included studies were included for meta-analysis. For the detection of norovirus, the pooled sensitivity, specificity, positive LR, negative LR, diagnostic OR, and their 95% CI were 0.96 (0.95-0.97), 0.99 (0.99-1.00), 91.14 (31.88-260.56), 0.06 (0.04-0.09), and 1473.68 (562.96-3857.70), respectively. Besides, AUC in the SROC curve was 0.9920. CONCLUSION: LAMP had high sensitivity and specificity in terms of the diagnosis of norovirus infection. However, further extension of this approach should be researched to ensure the accuracy and practicability of this hopeful test in the future.

Function Analysis of P450 and GST Genes to Imidacloprid in Aphis craccivora (Koch).

Aphis craccivora (Koch) is an economically important pest that affects legumes in worldwide. Chemical control is still the primary efficient method for A. craccivora management. However, the mechanism underlying insecticide resistance in A. craccivora has not been elucidated. A previous study observed that piperonyl butoxide (PBO) and diethyl maleate (DEM) significantly synergized imidacloprid in A. craccivora field populations, indicating that cytochrome P450 (P450) and glutathione S-transferase (GST) genes may play pivotal roles in imidacloprid resistance. In this study, 38 P450 genes and 10 GST genes were identified in A. craccivora through transcriptomic analysis. The expression levels of these P450 and GST genes were measured in susceptible (SUS) strains of A. craccivora under imidacloprid treatment with LC15, LC50, and LC85 doses. The expression levels of CYP18A1, CYP6CY21, CYP6DA1, CYP6DA2, CYP4CJ1, CYP4CJ2, and CYP380C6 were up-regulated in the three treatments. Most of these genes belong to CYP3 and CYP4 Clans. In addition, the expression levels of all P450 and GST genes in A. craccivora were also measured in the Juye (JY) and Linqing (LQ) field populations. The expression levels of CYP6DA2, CYP4CJ1, and CYP380C6 were up-regulated in the SUS strain after imidacloprid treatment at three doses, and these genes were overexpressed in the JY population. Furthermore, the sensitivity of A. craccivora to imidacloprid was significantly increased after knockdown of CYP380C6 and CYP6DA2 through RNA interference. These results may help to elucidate the mechanisms underlying of imidacloprid resistance in A. craccivora.