Objective:To assess the performance of mCIM in combination with eCIM test as well as Carba-5 and Carba-R tests in detecting common carbapenemases in carbapenem-resistant organisms (CRO).Methods:In this study, 122 non-duplicate clinical CRO strains isolated in Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, from January 2019 to December 2020 were randomly selected. These strains were identified using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). A modified carbapenem inactivation test (mCIM combined with eCIM test), Carba-5 and Carba-R were used to detect the types of carbapenemases in these strains. PCR results were used as the gold standard to evaluate the performance of the three methods.Results:The 122 CRO strains belonged to 12 different species. PCR results showed that carbapenemases were produced in 112 strains. KPC-2-producing strains accounted for 57% (70/122), which included 46 Klebsiella pneumoniae strains, 12 Pseudomonas aeruginosa strains and 12 other strains. OXA-232-positive strains accounted for 15% (19/122), with Klebsiella pneumoniae being the only carrier (100%, 19/19). NDM carbapenemases were identified in 16% of the strains (20/122), with NDM-1 and NDM-5 accounting for 35% (7/20) and 65% (13/20), respectively, and Escherichia coli was the predominant carrier (60%, 12/20). IMP-4 was detected in one Klebsiella pneumoniae strain and one Enterobacter asteri strain. One Klebsiella pneumoniae strain produced KPC-2 and IMP-4, while none of the strains were found to produce VIM carbapenemases. In the remaining 10 strains, none of the above-mentioned carbapenemases were detected. Compared with the golden standard, the mCIM combined with eCIM test had a sensitivity of 95.65% (22/23), a specificity of 100% (90/90), a positive predictive value (PPV) of 100% (22/22), a negative predictive value (NPV) of 98.90% (90/91), and a diagnostic accuracy of 99.11% (112/113). The sensitivity, specificity, PPV, NPV and diagnostic accuracy of Carba-5 and Carba-R tests were all 100%. Conclusions:In general clinical microbiology laboratories, Carba-5 test could be used as an accurate method to quickly detect common carbapenemases in carbapenem-resistant Enterobacterales and Pseudomonas aeruginosa strains. In advanced laboratories, Carba-R test could also be used to monitor the colonization of carbapenem-resistant bacteria in patients. If the results of both Carba-5 and Carba-R tests were negative, mCIM combined with eCIM test was recommended.

Objective To investigate the regulation role of gastric cancer related miR-148a on gastrin receptor CCKBR expression, and find the correct binding sites of miR-148a in CCKBR 3’UTR.Methods The potential binding sites of miR-148a in the CCKBR 3’UTR were predicted with the bioinformatic tools;The miR-148a expressing plasmid was constructed by PCR, and miR-148a expression was verified by Northern Blot;The luciferase report plasmids containing the wild type and mutated binding sites of CCKBR 3’ UTR were constructed, and were used to study the regulation mechanism and identify the binding sites of miR-148a by luciferase activity analysis; The regulation effect of miR-148a on CCKBR protein expression was checked by Western Blot.Results Three potential binding sites of miR-148a in the CCKBR 3’ UTR were found; The miR-148a expressing plasmid was constructed successfully, and highly expressed miR-148a after transfected to gastric cancer cells;The inhibitory effect of miR-148a on CCKBR protein expression was checked by Western Blot.Over-expression of miR-148a inhibited CCKBR expression by directly binding to the binding site in CCKBR 3’UTR 423bp.Conclusion CCKBR is a target of miR-148a, and its expression is inhibited by the binding of miR-148a on its 3’ UTR, indicating that miR-148a may participates in the progression of gastric cancer by regulating CCKBR expression.

IEST, DGS-COPT and CV-COPT using lyophilized ova of schistosoma japonicum were performed on sera from 120 cases of schistosomiasis japonica, 120 cases of schis-tosomiasis japonica 3-8 years after being cured with praziquantel and 120 healthy individuals by single-blind method. The sensitivity and specificity of IEST was 91.7% and 95.8% respectively which were significantly higher than that of both DGS-COPT and CV-COPT. The negative conversion rate of cured patients was 70.8% with IEST, 80.8% with DGS-COPT and 81.7% with CV-COPT. The results showed that IEST has higher diagnostic value for schistosomiasis than both COPT. DGS-COPT has the same diagnostic value as CV-COPT, however, it was easy to perform and time-saving, thus it might be applied in the fields for practical purposes.