Establishment and evaluation of a LAMP-CRISPR-based nucleic acid detection method for Schistosoma japonicum / 中国热带医学

@#Abstract: Objective To establish a sensitive and specific nucleic acid detection method for Schistosoma japonicum based on loop-mediated isothermal amplification (LAMP) and clustered regularly interspaced short palindromic repeats (CRISPR) technology. Methods The LAMP primers, gRNA and ssDNA probe that target Schistosoma japonicum SjR2 genes were designed according to the principles of LAMP and CRISPR. The LAMP-CRISPR reaction system was established and optimized. The sensitivity and specificity of the method were evaluated against the ten-fold serial dilutions of plasmid containing SjR2 target sequences, as well as genomic DNA at different stages of Schistosoma japonicum and other parasites, including Fasciola hepatica, Schistosoma mansoni, Taenia saginata, Clonorchis sinensis, Ascaris lumbricoides, Necator americanus, Paragonimus westermani, and Echinococcus granulosus. Additionally, 15 schistosome-infected snail and 30 uninfected samples were tested by LAMP-CRISPR and LAMP methods, respectively, to evaluate the potential of this method for screening for infected snails. Results　The developed LAMP-CRISPR method was able to specifically amplify and detect the SjR2 gene of S. japonicum. The optimal reaction temperature was 37 ℃, and the optimal reaction concentrations were both 40 nmol/L for gRNA and Cas12a protein. No cross-reaction was observed with genomic DNA from other parasites such as F. hepatica. The detection limit of the method was 10 copies/μL when testing 10-fold dilutions of recombinant plasmids as a template. Furthermore, the LAMP-CRISPR method was able to accurately detect genomic DNA from S. japonicum at various stages of development, including eggs, cercariae, schistosomula, juvenile worms, and adult worms. The results of testing 45 snail samples showed no significant difference between the LAMP-CRISPR and LAMP methods for detecting infected snails (χ2=0.05, P>0.05). The sensitivity and specificity of the LAMP-CRISPR method were 100.00% (15/15) and 96.67% (29/30), respectively, compared to the gold standard, while the sensitivity and specificity of the LAMP method were 100.00% (15/15) and 93.33% (28/30), respectively. Conclusions　This established LAMP-CRISPR detection method presented good sensitivity, specificity and reliability, making it a promising tool for rapid detection and risk monitoring of S. japonicum.

Diagnosis accuracy of PCA3 level in patients with prostate cancer: a systematic review with meta-analysis

ABSTRACT Background: The diagnostic value and suitability of prostate cancer antigen 3 (PCA3) for the detection of prostate cancer (PCa) have been inconsistent in previous studies. Thus, the aim of the present meta-analysis was performed to systematically evaluate the diagnostic value of PCA3 for PCa. Materials and Methods: A meta-analysis was performed to search relevant studies using online databases EMBASE, PubMed and Web of Science published until February 1st, 2019. Ultimately, 65 studies met the inclusion criteria for this meta-analysis with 8.139 cases and 14.116 controls. The sensitivity, specificity, positive likelihood ratios (LR+), negative likelihood ratios (LR−), and other measures of PCA3 were pooled and determined to evaluate the diagnostic rate of PCa by the random-effect model. Results: With PCA3, the pooled overall diagnostic sensitivity, specificity, LR+, LR−, and 95% confidence intervals (CIs) for predicting significant PCa were 0.68 (0.64-0.72), 0.72 (0.68-0.75), 2.41 (2.16-2.69), 0.44 (0.40-0.49), respectively. Besides, the summary diagnostic odds ratio (DOR) and 95% CIs for PCA3 was 5.44 (4.53-6.53). In addition, the area under summary receiver operating characteristic (sROC) curves and 95% CIs was 0.76 (0.72-0.79). The major design deficiencies of included studies were differential verification bias, and a lack of clear inclusion and exclusion criteria. Conclusions: The results of this meta-analysis suggested that PCA3 was a non-invasive method with the acceptable sensitivity and specificity in the diagnosis of PCa, to distinguish between patients and healthy individuals. To validate the potential applicability of PCA3 in the diagnosis of PCa, more rigorous studies were needed to confirm these conclusions.

Biapenem versus meropenem in the treatment of bacterial infections: a multicenter, randomized, controlled clinical trial.

Background & objectives: Biapenem is a newly developed carbapenem to treat moderate and severe bacterial infections. This multicenter, randomized, parallel-controlled clinical trial was conducted to compare the clinical efficacy, bacterial eradication rates and safety of biapenem and meropenem in the treatment of bacterial lower respiratory tract infections and urinary tract infections (UTIs) at nine centres in China. Methods: Patients diagnosed with bacterial lower respiratory tract infections or UTIs were randomly assigned to receive either biapenem (300 mg every 12 h) or meropenem (500 mg every 8 h) by intravenous infusion for 7 to 14 days according to their disease severity. The overall clinical efficacy, bacterial eradication rates and drug-related adverse reactions of biapenem and meropenem were analyzed. Results: A total of 272 enrolled cases were included in the intent-to-treat (ITT) analysis and safety analysis. There were no differences in demographics and baseline medical characteristics between biapenem group and meropenem group. The overall clinical efficacies of biapenem and meropenem were not significantly different, 94.70 per cent (125/132) vs. 93.94 per cent (124/132). The overall bacterial eradication rates of biapenem and meropenem showed no significant difference, 96.39 per cent (80/83) vs. 93.75 per cent (75/80). Drug-related adverse reactions were comparable in biapenem and meropenem groups with the incidence of 11.76 per cent (16/136) and 15.44 per cent (21/136), respectively. The most common symptoms of biapenem-related adverse reactions were rash (2.2%) and gastrointestinal distress (1.5%). Interpretation & conclusions: Biapenem was non-inferior to meropenem and was well-tolerated in the treatment of moderate and severe lower respiratory tract infections and UTIs.

Synergistic Effect of Hyperthermia and Neferine on Reverse Multidrug Resistance in Adriamycin-resistant SGC7901/ADM Gastric Cancer Cells / 华中科技大学学报（医学）（英德文版）

Multidrug resistance (MDR) plays a major obstacle to successful gastric cancer chemotherapy.The purpose of this study was to investigate the MDR reversal effect and mechanisms of hyperthermia in combination with neferine (Nef) in adriamycin (ADM) resistant human SGC7901/ADM gastric cancer cells.The MDR cells were heated at 42℃ and 45℃ for 30 min alone or combined with 10 μg/mL Nef.The cytotoxic effect of ADM was evaluated by MTT assay.Cellular plasma membrane lipid fluidity was detected by fluorescence polarization technique.Intracellular accumulation of ADM was monitored with high performance liquid chromatography.Mdr-1 mRNA,P-glycoprotein (P-gp),γH2AX expression and γH2AX foci formation were determined by real-time PCR,Western blot and immunocytochemical staining respectively.It was found that different heating methods induced different cytotoxic effects.Water submerged hyperthermia had the strongest cytotoxicity of ADM and Nef combined with hyperthermia had a synergistic cytotoxicity of ADM in the MDR cells.The water submerged hyperthermia increased the cell membrane fluidity.Both water submerged hyperthermia and Nef increased the intracellular accumulation of ADM.The water submerged hyperthermia and Nef down-regulated the expression of mdr-1 mRNA and P-gp.The water submerged hyperthermia could damage DNA and increase the γH2AX expression of SGC7901/ADM cells.The higher temperature was,the worse effect was.Our results show that combined treatment of hyperthermia with Nef can synergistically reverse MDR in human SGC7901/ADM gastric cancer cells.