Objective: To establish a real-time quality control scheme based on the median (MD-IC) of internal control cycle threshold value in negative samples (NEG-IC-CT), so as to monitor anomalies such as progressive drift in nucleic acid testing system not covered by conventional internal quality control (IQC) in blood center nucleic acid laboratories, and to verify its feasibility. Methods: The internal control CT values of 54 426 negative samples were retrospectively collected. These samples were from four reagent batches of the two new and old equipment sets during the operation of the Wantai nucleic acid testing system in our blood center. The daily median of NEG-IC-CT values was used as the research indicator. Control limits were calculated using median absolute deviation (MAD) to construct the Median-MAD quality control chart. The monitoring performance of this scheme for the operation status of the testing system was simultaneously evaluated. Results: Statistical analysis showed significant differences in NEG-IC-CT value distribution between the new and old equipment sets, as well as between the two different reagent batches of the old equipment (P<0.000 1). The NEG-IC-CT value performance of the two different reagent batches of the new equipment was no significant difference in distribution (P>0.05). This scheme identified three typies of distinct anomalies. The out-of-control events observed with the old equipment in both the O1 and O2 reagent batches suggested potential performance decay due to equipment aging. The unreported change of reagent batch in time of Phase B with new equipment caused a stepwise drift on the quality control chart. In the later stage of Phase A with the new equipment, an alert was triggered, indicating potential quality risks associated with practices such as the mixed use of the remaining reagents and extremely long operator working hours. Conclusion: The realtime quality control scheme based on NEG-IC-CT value established in this study has been preliminarily validated for its monitoring effectiveness in nucleic acid testing in our blood center. This scheme performed well in detecting differences among testing systems and reagent batches, serving as an effective supplement to routine internal quality control. It can provide an intuitive and effective evaluation method for monitoring the performance of the nucleic acid testing process at blood center.

Cigarette smoke extract (CSE)-treated mouse airway epithelial cells (MAECs)-derived exosomes accelerate the progression of chronic obstructive pulmonary disease (COPD) by upregulating triggering receptor expressed on myeloid cells 1 (TREM-1); however, the specific mechanism remains unclear. We aimed to explore the potential mechanisms of CSE-treated MAECs-derived exosomes on M1 macrophage polarization and pyroptosis in COPD. In vitro, exosomes were extracted from CSE-treated MAECs, followed by co-culture with macrophages.In vivo, mice exposed to cigarette smoke (CS) to induce COPD, followed by injection or/and intranasal instillation with oe-TREM-1 lentivirus. Lung function and pathological changes were evaluated. CD68 + cell number and the levels of iNOS, TNF-α, IL-1β (M1 macrophage marker), and pyroptosis-related proteins (NOD-like receptor family pyrin domain containing 3, apoptosis-associated speck-like protein containing a caspase-1 recruitment domain, caspase-1, cleaved-caspase-1, gasdermin D [GSDMD], and GSDMD-N) were examined. The expression of maternally expressed gene 3 (MEG3), spleen focus forming virus proviral integration oncogene (SPI1), methyltransferase 3 (METTL3), and TREM-1 was detected and the binding relationships among them were verified. MEG3 increased N6-methyladenosine methylation of TREM-1 by recruiting SPI1 to activate METTL3. Overexpression of TREM-1 or METTL3 negated the alleviative effects of MEG3 inhibition on M1 polarization and pyroptosis. In mice exposed to CS, EXO−CSE further aggravated lung injury, M1 polarization, and pyroptosis, which were reversed by MEG3 inhibition. TREM-1 overexpression negated the palliative effects of MEG3 inhibition on COPD mouse lung injury. Collectively, CSE-treated MAECs-derived exosomal long non-coding RNA MEG3 may expedite M1 macrophage polarization and pyroptosis in COPD via the SPI1/METTL3/TREM-1 axis.

Objective To obtain methamphetamine concentration profiles in saliva and urine samples of drug addicts and to screen the colloidal gold strip. Methods Methamphetamine concentration in saliva and urine samples of drug addicts was determined by liquid chromatography tandem mass spectrometry. The initial screening was obtained by colloidal gold strip test. The results were compared and analyzed. Results using the method of protein and fluid MRM scan method to detect direct precipitation, saliva is linear in the range of 1~100ng/mL, the linear correlation coefficient is 0.9987, the detection limit is 0.1ng/mL, the limit of quantification was 1ng/mL, the urine is linear in the range of 1~100ng/mL, the linear correlation coefficient is 0.9943, the detection limit is 0.5ng/mL, the limit of quantification was 1ng/mL. Saliva and urine samples diluted, the concentration in the linear range. Saliva and urine samples of four types of methamphetamine colloidal gold reagent strip were screened directly, and the results were judged visually. Conclusion the detection rate of colloidal gold strip is about 79%, the detection rate of saliva is about 81%, and the detection rate can be increased to more than 93% by using two reagent strips. Combined with the initial screening results and the instrument confirmation concentration, it can be found that the gray zone setting and sensitivity setting have certain influence on the detection rate, and it is suggested to improve the sensitivity to meet the needs of screening.