Enhanced patient-based real-time quality control using the graph-based anomaly detection.

OBJECTIVES: Patient-based real-time quality control (PBRTQC) is an alternative tool for laboratories that has gained increasing attention. Despite the progress made by using various algorithms, the problems of data volume imbalance between in-control and out-of-control results, as well as the issue of variation remain challenges. We propose a novel integrated framework using anomaly detection and graph neural network, combining clinical variables and statistical algorithms, to improve the error detection performance of patient-based quality control. METHODS: The testing results of three representative analytes (sodium, potassium, and calcium) and eight independent variables of patients (test date, time, gender, age, department, patient type, and reference interval limits) were collected. Graph-based anomaly detection network was modeled and used to generate control limits. Proportional and random errors were simulated for performance evaluation. Five mainstream PBRTQC statistical algorithms were chosen for comparison. RESULTS: The framework of a patient-based graph anomaly detection network for real-time quality control (PGADQC) was established and proven feasible for error detection. Compared with classic PBRTQC, the PGADQC showed a more balanced performance for both positive and negative biases. For different analytes, the average number of patient samples until error detection (ANPed) of PGADQC decreased variably, and reductions could reach up to approximately 95 % at a small bias of 0.02 taking calcium as an example. CONCLUSIONS: The PGADQC is an effective framework for patient-based quality control, integrating statistical and artificial intelligence algorithms. It improves error detection in a data-driven fashion and provides a new approach for PBRTQC from the data science perspective.

A turn-on fluorescent strategy for alkaline phosphatase detection based on enzyme-assisted signal amplification.

As a representative biochemical indicator, alkaline phosphatase (ALP) is of great importance in indicating and diagnosing clinical diseases. Herein, we developed a signal-on fluorescence sensing method for sensitive ALP activity detection based on the enzyme-assisted target recycling (EATR) technique. In this method, a two-step signal amplification process is designed. In the presence of ALP, the 3' phosphate group of an ss-DNA is removed explicitly by ALP, thus releasing free 3'-OH. Terminal deoxynucleotidyl transferase (TdT) can subsequently extend this substrate to generate poly(A) tails, converting the trace-level ALP information into multiple sequences and achieving the first-time amplification. A poly(T) Taqman probe labeled with FAM and BHQ1 provides the second one under the assistance of T7 exonuclease (T7 Exo) through alternate hybridization and degradation of ds-DNA regions. The previously quenched fluorescence is recovered due to the departure of FAM/BHQ1 during the cleavage of T7 Exo. Thus, taking advantage of template-free TdT-mediated polymerization and T7 Exo-based EATR, this strategy shows a sensitive LOD at 0.0074 U/L (S/N = 3) and a linear range of 0.01-8 U/L between ALP concentration and fluorescence intensity. To further verify the specificity and accuracy in practical application, we challenged it in a set of co-existing interference and biological environments and have gained satisfying results. The proposed method successfully quantified the ALP levels in clinical human serum samples, suggesting its applicability in practical application. Moreover, we have used this method to investigate the inhibition effects of Na3VO4. Above all, the proposed assay is sensitive, facile, and cost-effective for ALP determining, holding a promising perspective and excellent potential in clinical diagnosis and drug screening.

A fluorescent assay for alkaline phosphatase activity based on phosphorylation protection and DNAzyme-assisted amplification.

Alkaline phosphatase is one of the most important tool enzymes and diseases indicator, monitoring ALP activity with convenient, precise, efficient and sensitive methods plays a fundamental role in modern life and healthcare industries. In this study, we described a novel method for ALP analysis based on Pb2+ dependent DNAzyme. By modifying DNAzyme sequence with terminal phosphate group and introducing exonuclease I (exo I), we managed to analyze ALP by utilizing its causal function of DNAzyme probe from exo I mediated degradation and function of triggering the subsequent cleavage of the hairpin reporting probe. Other than one amplificative strategy by DNAzyme mediated cleavage and cycle, this system also involved an exo I mediated degradation to further reduce the background noise. Combining stepwise fluorimetry and electrophoresis, we verified the detective mechanism of this proposed method. Further, after selectivity demonstration, this method achieved a considerable LOD of 0.0017 U L-1 and linear range of 0.0025 U L-1 to 250 U L-1. For potential of practical application, this method also exhibited excellent performances in inhibitor screening and intracellular ALP assay, both with a linear fitting equation. Based on these results, this method should be highly committed for improving ALP analysis in modern life industry.

Platelet membrane-camouflaged silver metal-organic framework drug system against infections caused by methicillin-resistant Staphylococcus aureus.

BACKGROUND: Due to the intelligent survival strategy and self-preservation of methicillin-resistant Staphylococcus aureus (MRSA), many antibiotics are ineffective in treating MRSA infections. Nano-drug delivery systems have emerged as a new method to overcome this barrier. The aim of this study was to construct a novel nano-drug delivery system for the treatment of MRSA infection, and to evaluate the therapeutic effect and biotoxicity of this system. We prepared a nano silver metal-organic framework using 2-methylimidazole as ligand and silver nitrate as ion provider. Vancomycin (Vanc) was loaded with Ag-MOF, and nano-sized platelet vesicles were prepared to encapsulate Ag-MOF-Vanc, thus forming the novel platelet membrane-camouflaged nanoparticles PLT@Ag-MOF-Vanc. RESULTS: The synthesized Ag-MOF particles had uniform size and shape of radiating corona. The mean nanoparticle size and zeta potential of PLT@Ag-MOF-Vanc were 148 nm and - 25.6 mV, respectively. The encapsulation efficiency (EE) and loading efficiency (LE) of vancomycin were 81.0 and 64.7 %, respectively. PLT@Ag-MOF-Vanc was shown to be a pH-responsive nano-drug delivery system with good biocompatibility. Ag-MOF had a good inhibitory effect on the growth of three common clinical strains (Escherichia coli, Pseudomonas aeruginosa, and S. aureus). PLT@Ag-MOF-Vanc showed better antibacterial activity against common clinical strains in vitro than free vancomycin. PLT@Ag-MOF-Vanc killed MRSA through multiple approaches, including interfering with the metabolism of bacteria, catalyzing reactive oxygen species production, destroying the integrity of cell membrane, and inhibiting biofilm formation. Due to the encapsulation of the platelet membrane, PLT@Ag-MOF-Vanc can bind to the surface of the MRSA bacteria and the sites of MRSA infection. PLT@Ag-MOF-Vanc had a good anti-infective effect in mouse MRSA pneumonia model, which was significantly superior to free vancomycin, and has no obvious toxicity. CONCLUSIONS: PLT@Ag-MOF-Vanc is a novel effective targeted drug delivery system, which is expected to be used safely in anti-infective therapy of MRSA.

Novel Multifunctional Silver Nanocomposite Serves as a Resistance-Reversal Agent to Synergistically Combat Carbapenem-Resistant Acinetobacter baumannii.

In the face of the abundant production of various types of carbapenemases, the antibacterial efficiency of imipenem, seen as "the last line of defense", is weakening. Following, the incidence of carbapenem-resistant Acinetobacter baumannii (CRAB), which can generate antibiotic-resistant biofilms, is increasing. Based on the superior antimicrobial activity of silver nanoparticles against multifarious bacterial strains compared with common antibiotics, we constructed the IPM@AgNPs-PEG-NOTA nanocomposite (silver nanoparticles were coated with SH-PEG-NOTA as well as loaded by imipenem) whose core was a silver nanoparticle to address the current challenge, and IPM@AgNPs-PEG-NOTA was able to function as a novel smart pH-sensitive nanodrug system. Synergistic bactericidal effects of silver nanoparticles and imipenem as well as drug-resistance reversal via protection of the ß-ring of carbapenem due to AgNPs-PEG-NOTA were observed; thus, this nanocomposite confers multiple advantages for efficient antibacterial activity. Additionally, IPM@AgNPs-PEG-NOTA not only offers immune regulation and accelerates tissue repair to improve therapeutic efficacy in vivo but also can prevent the interaction of pathogens and hosts. Compared with free imipenem or silver nanoparticles, this platform significantly enhanced antibacterial efficiency while increasing reactive oxygen species (ROS) production and membrane damage, as well as affecting cell wall formation and metabolic pathways. According to the results of crystal violet staining, LIVE/DEAD backlight bacterial viability staining, and real-time quantitative polymerase chain reaction (RT-qPCR), this silver nanocomposite downregulated the levels of ompA expression to prevent formation of biofilms. In summary, this research demonstrated that the IPM@AgNPs-PEG-NOTA nanocomposite is a promising antibacterial agent of security, pH sensitivity, and high efficiency in reversing resistance and synergistically combatting carbapenem-resistant A. baumannii. In the future, various embellishments and selected loads for silver nanoparticles will be the focus of research in the domains of medicine and nanotechnology.

Cautions on the laboratory indicators of COVID-19 patients on and during admission.

BACKGROUND: Different disease severities of COVID-19 patients could be reflected on clinical laboratory findings. METHODS: In this single-centered retrospective study, demographic, clinical, and laboratory indicators on and during admission were compared among 74 participants with mild, moderate, critical severe, or severe classification. Risk factors associated with disease severity were analyzed by multivariate analyses. The AUC and 95% CI of the ROC curve were calculated. RESULTS: The most common manifestations of these patients were fever and cough. Critical severe or severe group owned the longest length of stay (23 (19,31), p < 0.001). After multivariate logistic regression, independent influence factors on admission for severity of disease were CK-MB (OR 0.674; 95% CI 0.489-0.928; p = 0.016), LDH (OR 1.111 or 1.107; 95% CI 1.026-1.204 or 1.022-1.199; p = 0.009 or 0.013), normal T-BIL (OR 4.58 × 10-8 ; 95% CI 3.05 × 10-9 -6.88 × 10-7 ; p < 0.001), LYM% (OR 0.008; 95% CI 0-0.602; p = 0.029), and normal ESR (OR 0.016; 95% CI 0-0.498; p = 0.019). Factors during hospitalization were normal T-BIL (OR 8.56 × 10-9 ; 95% CI 8.30 × 10-10 -8.83 × 10-8 ; p < 0.001), LYM (OR 0.068; 95% CI 0.005-0.934; p = 0.044), albumin (OR 0.565; 95% CI 0.327-0.977; p = 0.041), and normal NEU% (OR 0.013; 95% CI 0.000-0.967; p = 0.048). Combined indicators of AUC were 0.860 (LYM, LDH, and normal ESR on admission, p < 0.001) and 0.750 (CK-MB, LDH, and normal T-BIL during hospitalization, p = 0.020) when predicting for severe or critical severe patients. CONCLUSION: To pay close attention to the progression of COVID-19 and take measures promptly, we should be cautious of the laboratory indicators when patients on admission especially CK-MB, LDH, LYM%, T-BIL as well as ESR; and T-BIL, LYM, albumin, NEU% with the process of disease.

A survey of laboratory biosafety and protective measures in blood transfusion departments during the COVID-19 pandemic.

BACKGROUND AND OBJECTIVES: Thousands of healthcare workers (HCWs) have been infected with 2019 novel coronavirus pneumonia (COVID-19) during the COVID-19 pandemic. Laboratory personnel in blood transfusion departments may be infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) if laboratory biosafety protection is insufficient. Therefore, we investigated the current situation of laboratory biosafety protection in blood transfusion departments to determine how to improve the safety of laboratory processes. MATERIALS AND METHODS: An online survey was conducted in blood transfusion departments from 1st to 6th May 2020 in China. A total of 653 individuals completed the questionnaire. The questionnaire was designed with reference to COVID-19 laboratory biosafety summarized in Annex II. All responses were summarized using only descriptive statistics and expressed as frequencies and ratios [n (%)]. RESULTS: Most participants were concerned about COVID-19. Some participants had inadequate knowledge of COVID-19. Two participants stated that there were laboratory personnel infected with SARS-CoV-2 in their departments. A total of 31 (4.7%) participants did not receive any safety and security training. In terms of laboratory biosafety protection practices, the major challenges were suboptimal laboratory safety practices and insufficient laboratory conditions. CONCLUSION: The major deficiencies were insufficient security and safety training, and a lack of personal protective equipment, automatic cap removal centrifuges and biosafety cabinets. Consequently, we should enhance the security and safety training of laboratory personnel to improve their laboratory biosafety protection practices and ensure that laboratory conditions are sufficient to improve the safety of laboratory processes.

Intestinal Flora Disruption and Novel Biomarkers Associated With Nasopharyngeal Carcinoma.

Background: Nasopharyngeal carcinoma (NPC) is a malignant nasopharyngeal disease with a complicated etiology that occurs mostly in southern China. Intestinal flora imbalance is believed to be associated with a variety of organ malignancies. Current studies revealed that the destruction of intestinal flora is associated with NPC, and many studies have shown that intestinal flora can be used as a biomarker for many cancers and to predict cancer. Methods: To compare the differences in intestinal flora compositions and biological functions among 8 patients with familial NPC (NPC_F), 24 patients with sporadic NPC (NPC_S), and 27 healthy controls (NOR), we compared the intestinal flora DNA sequencing and hematological testing results between every two groups using bioinformatic methods. Results: Compared to the NOR group, the intestinal flora structures of the patients in the NPC_F and NPC_S groups showed significant changes. In NPC_F, Clostridium ramosum, Citrobacter spp., Veillonella spp., and Prevotella spp. were significantly increased, and Akkermansia muciniphila and Roseburia spp. were significantly reduced. In NPC_S, C. ramosum, Veillonella parvula, Veillonella dispar, and Klebsiella spp. were significantly increased, and Bifidobacterium adolescentis was significantly reduced. A beta diversity analysis showed significant difference compared NPC_F with NOR based on Bray Curtis (P = 0.012) and Unweighted UniFrac (P = 0.0045) index, respectively. The areas under the ROC curves plotted were all 1. Additionally, the concentrations of 5-hydroxytryptamine (5-HT) in NPC_F and NPC_S were significantly higher than those of NOR. C. ramosum was positively correlated with 5-HT (rcm: 0.85, P < 0.001). A functional analysis of the intestinal flora showed that NPC_F was associated with Neurodegenerative Diseases (P = 0.023) and that NPC_S was associated with Neurodegenerative Diseases (P = 0.045) as well. Conclusion: We found that NPC was associated with structural imbalances in the intestinal flora, with C. ramosum that promoted the elevation of 5-HT and opportunistic pathogens being significantly increased, while probiotics significantly decreased. C. ramosum can be used as a novel biomarker and disease prediction models should be established for NPC. The new biomarkers and disease prediction models may be used for disease risk prediction and the screening of high-risk populations, as well as for the early noninvasive diagnosis of NPC.