Electrochemical Lateral Flow Immunoassay with Built-In Electrodes for Ultrasensitive and Wireless Detection of Inflammatory Biomarkers.

Paper-based lateral flow immunoassays (LFIAs) are cost-effective, portable, and simple methods for detection of diverse analytes, which however only provide qualitative or semiquantitative results and lack sufficient sensitivity. A combination of LFIA and electrochemical detection, namely, electrochemical lateral flow immunoassay (eLFIA), enables quantitative detection of analytes with high sensitivity, but the integration of external electrodes makes the system relatively expensive and unstable. Herein, the working, counter, and reference electrodes were prepared directly on the nitrocellulose membrane using screen printing, which remarkably simplified the structure of eLFIA and decreased the cost. Moreover, a horseradish peroxidase (HRP)-based electrochemical signal amplification strategy was used for further increasing the analytical sensitivity. HRP captured on the working electrode can catalyze the oxidation of tetramethylbenzidine (TMB) to form the TMB-TMBox precipitate on the electrode surface, which as an electrochemically active product can output an amplified current for quantification. We demonstrated that the eLFIA could detect low-abundant inflammatory biomarkers in human plasma samples with limits of detection of 0.17 and 0.54 pg mL-1 for interleukin-6 and C-reactive protein, respectively. Finally, a fully portable system was fabricated by integrating eLFIA with a flexible and wireless electrochemical workstation, realizing the point-of-care detection of interleukin-6.

Evaluation of effects from hemoglobin variants on HbA1c measurements by different methods.

OBJECTIVES: The impact of seven hemoglobin variants (Hb Q-Thailand, Hb G-Honolulu, Hb Ube-2, Hb New York, Hb J-Bangkok, Hb G-Coushatta, and Hb E) on the outcome of HbA1c was investigated for six methods by comparing with liquid chromatography-tandem mass spectrometry (LC/MS/MS) reference method. METHODS: Twenty-nine normal and 112 variant samples were measured by LC/MS/MS, Sebia Capillarys 3 TERA, Intelligene Biosystems QuanTOF, Premier Hb9210, Arkray HA-8190V, Bio-Rad D-100, and Tosoh G11, then evaluated for correlation, consistency, and mean relative bias among six methods. The lowest biological variation bias of ±2.8 % was an acceptable standard. RESULTS: All methods showed poor correlation and consistency with LC/MS/MS for Hb E. The unacceptable biases were observed for Capillarys 3 TERA (-14.4 to -3.7 % for Hb Q-Thailand, Hb Ube-2, Hb New York, Hb J-Bangkok and Hb E), QuanTOF (-8.3 to -2.9 % for Hb Ube-2, Hb New York and Hb G-Coushatta), Premier Hb9210 (-18.3 to -3.6 % for Hb Q-Thailand, Hb Ube-2, Hb New York, Hb J-Bangkok and Hb E), HA-8190V variant mode (-17.3 to 6.6 % for Hb G-Honolulu, Hb Ube-2, Hb New York, Hb G-Coushatta and Hb E). All variant samples showed larger biases than ±2.8 % comparing HA-8190V fast mode, D-100, and G11 with LC/MS/MS. CONCLUSIONS: The accuracy of different HbA1c methods was influenced by some Hb variants, especially Hb Ube-2 and Hb New York. Thus, laboratories need to choose appropriate methods to measure HbA1c with different Hb variants.

Comparable analysis of six immunoassays for carcinoembryonic antigen detection.

Objective: This study aimed to assess the current status of carcinoembryonic antigen (CEA) detection. We evaluated the correlation, consistency, and comparability of CEA results among six automated immunoassays, and combined with the results of CEA trueness verification of the Beijing Center for Clinical Laboratories (BCCL) for further analysis. Methods: Abbott Architect i2000, Beckman DxI800, Roche Cobas E601, Diasorin Liaison XL, Maccura IS1200, and Autolumo A2000 were used to detect 40 individual serum CEA samples. Taking the optimal analytical quality specifications calculated from data on biological variation as the evaluation criterion. Passing-Bablok regression and Bland-Altman analysis were performed between each assay and all-assays median values to evaluate the correlation and relative difference. The concordance correlation coefficient (CCC) was used for consistency analysis. Additionally, the trueness verification program used samples at three concentration levels to assess the bias, coefficient of variation (CV), and total error (TE) between the average measured values and the target value. Results: The Spearman's rank correlation coefficient (rs) was ≥0.996 and the CCC ranged between 0.9448 and 0.9990 for each assay vs. all-assays median. Considering the all-assays median value of each sample as a reference, there were proportional and systematic differences according to the Passing-bablok regression analysis. The relative difference of the four assays (Abbott Architect i2000, Autolumo A2000, Diasorin Liaison XL, and Maccura IS1200) met the optimal analytical quality specifications. On the other hand, Beckman DxI800 (13.2 %) and Roche Cobas E601 (-9.0 %) were only able to fulfill the desirable analytical quality specifications. The average pass rates for bias, CV, and TE of the trueness verification program were 80 %, 98 %, and 96 %, respectively. Conclusions: The six automated immunoassays vs. all-assays median have a good correlation in CEA detection. However, there is a lack of comparability of CEA results. Further improvements are needed in harmonization among CEA detections.

Proteomics analysis of serum and urine identifies VCP and CTSA as potential biomarkers associated with multiple myeloma.

AIMS: We analyzed the differentially expressed proteins (DEPs) in serum and urine in order to provide new potential biomarkers for MM. METHODS: Data-Independent Acquisition-based proteomics of serum and urine was performed to identify potential biomarkers for MM patients. Then we performed Western Blotting (WB), ELISA along with their ROC curve analysis to confirm DEPs. RESULTS: A total of 1653 proteins in serum and 4519 proteins in urine were identified using Data-Dependent Acquisition method. VCP was the only protein that showed significant differences in different comparison groups in both serum and urine. Pathway analysis revealed that protein processing in the endoplasmic reticulum was the most relevant pathway associated with MM. Furthermore, the increased expression of HSP90B1, VCP, CTSA, HYOU1, PDIA4, and RAB7A was detected by WB. The results of ELISA indicated that a combination of VCP and CTSA provided a high area under curve (AUC) value of 0.883 (95 % CI, 0.769-0.997, p < 0.001) to diagnose NDMM. The combination of VCP, CTSA, ALB, and HGB exhibited better performance (AUC = 0.981), with 100 % specificity and 86.7 % sensitivity. CONCLUSION: These findings suggest VCP and CTSA exhibit potential as biomarkers for MM, which may be helpful in the molecular mechanisms and pathogenesis upon further investigation.

Changes in Laboratory Indexes for Multiple Myeloma Patients Before and After Autologous Stem Cell Transplant.

Purpose: Outcomes after autologous stem cell transplantation (ASCT) are quite variable and difficult to predict. Second-generation flow, second-generation sequencing, and other tests are invasive and expensive for patients. In this study, we aimed to analyze laboratory data before and after transplantation to look for laboratory indicators that could predict disease progression in patients with newly diagnosed multiple myeloma (NDMM) patients underwent ASCT. Patients and Methods: Standard complete blood count (CBC) parameters, clinical biochemical, and immunological indicators on day -5 and day 90 after ASCT were obtained. Receiver-operating characteristic (ROC) curve was used to determine the cutoff values, we evaluated the predictive abilities of laboratory parameters for progression-free survival (PFS). Univariate and multivariate analyses were performed to evaluate the prognostic significance of variables associated with the PFS of 166 NDMM who underwent ASCT. Results: At day-5, a low absolute monocyte count (AMC, p=0.001), systemic inflammation response index<1.56 (SIRI, P=0.03), serum calcium (p=0.02), and albumin (p=0.006) can predict for superior PFS. At Day +90, a high absolute neutrophil count (ANC, p = 0.008) and lymphocyte-to-monocyte ratio (LMR, p = 0.02), a low neutrophil-to-lymphocyte ratio (NLR, p =0.02) and SIRI<0.41 (p=0.02) predicted for superior PFS. Conclusion: There are inflammation-related indicators derived from peripheral blood cell count (WBCC) - ANC, NLR, SIRI, and LMR - which can serve as potential biomarkers for predicting PFS of NDMM patients underwent ASCT.

Microplastic stress in plants: effects on plant growth and their remediations.

Microplastic (MP) pollution is becoming a global problem due to the resilience, long-term persistence, and robustness of MPs in different ecosystems. In terrestrial ecosystems, plants are exposed to MP stress, thereby affecting overall plant growth and development. This review article has critically analyzed the effects of MP stress in plants. We found that MP stress-induced reduction in plant physical growth is accompanied by two complementary effects: (i) blockage of pores in seed coat or roots to alter water and nutrient uptake, and (ii) induction of drought due to increased soil cracking effects of MPs. Nonetheless, the reduction in physiological growth under MP stress is accompanied by four complementary effects: (i) excessive production of ROS, (ii) alteration in leaf and root ionome, (iii) impaired hormonal regulation, and (iv) decline in chlorophyll and photosynthesis. Considering that, we suggested that targeting the redox regulatory mechanisms could be beneficial in improving tolerance to MPs in plants; however, antioxidant activities are highly dependent on plant species, plant tissue, MP type, and MP dose. MP stress also indirectly reduces plant growth by altering soil productivity. However, MP-induced negative effects vary due to the presence of different surface functional groups and particle sizes. In the end, we suggested the utilization of agronomic approaches, including the application of growth regulators, biochar, and replacing plastic mulch with crop residues, crop diversification, and biological degradation, to ameliorate the effects of MP stress in plants. The efficiency of these methods is also MP-type-specific and dose-dependent.

Accurate method for value assignment of carcinoembryonic antigen reference materials.

BACKGROUND: In this study, we explored the commutability of reference materials (RMs) for carcinoembryonic antigen (CEA), selected the appropriate diluent matrix of the first International Reference Preparation (IRP) 73/601 of the World Health Organization (WHO 73/601) for CEA, and improved the comparability of CEA measurement results among different assay systems. METHODS: Forty serum samples were divided into five aliquots. WHO 73/601 was diluted into nine concentrations using five diluents with different components, and the candidate RMs for CEA at five concentrations (C1-C5) were prepared by the Beijing Clinical Laboratory Center (BCCL). The samples were analyzed via five automated CEA immunoassays. RESULTS: Carcinoembryonic antigen candidate RMs were commutable among all immunoassays based on the CLSI approach and among 7 of 10 assay combinations based on the IFCC approach. WHO 73/601 diluted in phosphate-buffered saline (PBS) was commutable among all assays based on the CLSI approach and among 5 of 10 pairwise comparisons based on the IFCC approach with correction of bias at diluted concentrations, except for the lowest concentration, which had the smallest variation among systems. The median percentage biases among assays were decreased after calibration. CONCLUSION: The BCCL candidate RMs (C2-C5) for CEA were commutable among all immunoassays. WHO 73/601 RMs diluted in a PBS buffer matrix were selected as common calibrators for five immunoassays, which reduced bias, thereby effectively improving the harmonization of CEA detection; therefore, they could be used to assign values to CEA candidate RMs developed by BCCL. Our findings promote the harmonization of CEA detection in immunoassays.

An integrated microfluidic electrochemiluminescence device for point-of-care testing of acute myocardial infarction.

Heart-type fatty acid binding protein (H-FABP) is an early biomarker for acute myocardial infarction. The concentration of H-FABP in circulation sharply increases during myocardial injury. Therefore, fast and accurate detection of H-FABP is of vital significance. In this study, we developed an electrochemiluminescence device integrated with microfluidic chip (designed as m-ECL device) for on-site detection of H-FABP. The m-ECL device is consisted of a microfluidic chip that enable easy liquid handling as well as an integrated electronic system for voltage supply and photon detection. A sandwich-type ECL immunoassay strategy was employed for H-FABP detection by using Ru (bpy)32+ loaded mesoporous silica nanoparticles as ECL probes. This device can directly detect H-FABP in human serum without any pre-treatment, with a wide linear range of 1-100 ng/mL and a low limit of detection of 0.72 ng/mL. The clinical usability of this device was evaluated using clinical serum samples from patients. The results obtained from m-ECL device are well matched with those obtained from ELISA assays. We believe this m-ECL device has extensive application prospects for point-of-care testing of acute myocardial infarction.

The effect of therapeutic physical modalities on pain, function, and quality of life in patients with myofascial pain syndrome: a systematic review.

BACKGROUND: Myofascial pain syndrome (MPS) is a common musculoskeletal pain and dysfunction, which is characterised by myofascial trigger points. Therapeutic physical modalities, as potentially effective treatment options, are commonly used in the clinical setting for the patients with MPS. OBJECTIVE: This systematic review aimed to evaluate the safety and effectiveness of therapeutic physical modalities in the treatment of MPS, investigate its therapeutic mechanisms and provide a scientific evidence-based decision. METHODS: According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, the PubMed, Cochrane Central Library, Embase, and CINAHL databases were searched for randomized controlled clinical studies published from database inception to October 30, 2022. A total of 25 articles met the study inclusion criteria. Data were extracted from these studies and a qualitative analysis was performed. RESULTS: Transcutaneous electrical nerve stimulation therapy, extracorporeal shock wave therapy, laser therapy, and other therapeutic physical modalities have been demonstrated to improve the pain symptoms, joint mobility, psychological state, and quality of life in the patients with MPS and no side effects have been reported. The curative effect of therapeutic physical modalities was found to be possibly associated with increased blood perfusion and oxygen supply in ischaemic tissues, reduced hyperalgesia in the peripheral and central nerves, and decreased involuntary muscle contractions. CONCLUSION: The systematic review has shown that therapeutic physical modalities could provide a safe and effective therapeutic option for MPS. However, the consensus is currently lacking regarding the optimal treatment paradigm, therapeutic parameters, and mutual combination of therapeutic physical modalities. The clinical trials with robust quality are required to further promote the evidence-based application of therapeutic physical modalities for MPS.

[Metabolic engineering of Escherichia coli for production of malonic acid].

Malonic acid is an important dicarboxylic acid, which can be widely used in the fields of chemical industry, medicine and food. In this study, a recombinant Escherichia coli strain BL21(TPP) was constructed to synthesize malonate through overexpressing six genes of ppc, aspC, panD, pa0132, yneI and pyc. Under shake flask fermentation conditons, strain BL21(TPP) produced 0.61 g/L malonic acid. In a 5 L fermentor, the production of malonic acid reached 3.32 g/L by using an intermittent feeding strategy. Next, a recombinant strain BL21(SCR) was constructed by fusional expression of ppc and aspC, as well as pa0132 and yneI, respectively. As a result, the production of malonic acid increased to 0.83 g/L at the shake flask level, which was a 36% increase over the starting strain BL21(TPP). Finally, the highest malonate production reached 5.61 g/L in a 5 L fermentor, which was a 69% increase over the starting strain BL21(TPP). Production of malonic acid by metabolically engineered E. coli provides a basis for further optimization, and may also serve as a reference for the biosynthesis of other dicarboxylic acids.

Metabolic engineering of the malonyl-CoA pathway to efficiently produce malonate in Saccharomyces cerevisiae.

Malonate is a platform chemical that has been utilized to synthesize many valuable chemical compounds. Here, Saccharomyces cerevisiae was metabolically engineered to produce malonate through the malonyl-CoA pathway. To construct the key step of converting malonyl-CoA to malonate, a native mitochondrial 3-hydroxyisobutyryl-CoA hydrolase gene EHD3 was mutated to target the cytoplasm and obtain malonyl-CoA hydrolase activity. The malonyl-CoA hydrolase activity of Ehd3 was achieved by mutating the malonyl-CoA binding site F121 to I121 and the active site E124 to seven amino acids (S/T/H/K/R/N/Q). We identified that the strain with E124S mutation had the highest malonate titer with 13.6 mg/L. Genomic integration of the mutant EHD3 and ACC1** to delta sequence sites was further explored to increase their reliable expression. Accordingly, a screening method with the work flow of fluorescence detection, shake-tube fermentation, and shake-flask fermentation was constructed to screen high copy delta sequences efficiently. The malonate titer was improved to 73.55 mg/L after screening the ∼1500 integrative strains, which was increased 4.4-folds than that of the episomal strain. We further engineered the strain by regulating the expression of key enzyme in the malonyl-CoA pathway to improve the precursor supply and inhibiting its competing pathways, and the final engineered strain LMA-16 produced 187.25 mg/L in the flask, 14-fold compared with the initial episomal expression strain. Finally, the combined efforts increased the malonate titer to 1.62 g/L in fed-batch fermentation.

Programmable Synthetic Upstream Activating Sequence Library for Fine-Tuning Gene Expression Levels in Saccharomyces cerevisiae.

A wide dynamic range of promoters is necessary for fine-tuning transcription levels. However, weak intensity and narrow dynamic range limit transcriptional regulation via constitutive promoters. The upstream activation sequence (UAS) located upstream of the core promoter is a crucial region that could obviously enhance promoter strength. Herein, we created a random mutagenesis library consisting of 330 different variants based on the UAS of the TDH3 promoter with an ∼37-fold dynamic range by error-prone polymerase chain reaction (PCR) and obtained strong intensity mutant UAS, which was ∼12-fold greater than the wild-type UASTDH3. Analysis of the mutant library revealed 15 strength-enhancing sites and their corresponding bases of the UASTDH3 regions, which provided the impetus for a synthetic library. The resulting 32 768 mutant UAS library was constructed by permutation and combination of the bases of the 15 enhancing sites. To characterize the library, a strength prediction model was built by correlating DNA structural features and UAS strength, which provided a model between UAS sequence and intensity. Following characterization, the UAS library was applied to precisely regulate gene expression in the production of ß-carotene, proving that the UAS library would be a useful tool for gene tuning in metabolic engineering. In summary, we designed, constructed, and characterized a UAS library that facilitated precise tuning of transcription levels of target proteins.

Role of Calcium/Calcineurin Signalling in Regulating Intracellular Reactive Oxygen Species Homeostasis in Saccharomyces cerevisiae.

The calcium/calcineurin signalling pathway is required for cell survival under various environmental stresses. Using Saccharomyces cerevisiae, we explored the mechanism underlying calcium-regulated homeostasis of intracellular reactive oxygen species (ROS). We found that deletion of acyltransferase Akr1 and C-5 sterol desaturase Erg3 increased the intracellular ROS levels and cell death, and this could be inhibited by the addition of calcium. The hexose transporter Hxt1 and the amino acid permease Agp1 play crucial roles in maintaining intracellular ROS levels, and calcium induced the expression of the HXT1 and AGP1 genes. The cytosolic calcium concentration was decreased in both the akr1Δ and erg3Δ mutants relative to wild-type cells, potentially lowering basal expression of HXT1 and AGP1. Moreover, the calcium/calcineurin signalling pathway also induced the expression of AKR1 and ERG3, indicating that Akr1 and Erg3 might perform functions that help yeast cells to survive under high calcium concentrations. Our results provided mechanistic insight into how calcium regulated intracellular ROS levels in yeast.

Spatially Selective Imaging of Cell-Matrix and Cell-Cell Junctions by Electrochemiluminescence.

Cell junctions are protein structures located at specific cell membrane domains that determine key processes in multicellular development. Here we report spatially selective imaging of cell junctions by electrochemiluminescence (ECL) microscopy. By regulating the concentrations of luminophore and/or co-reactant, the thickness of ECL layer can be controlled to match with the spatial location of different cell junctions. At a low concentration of luminophore, ECL generation is confined to the electrode surface, thus revealing only cell-matrix adhesions at the bottom of cells. While at a high concentration of luminophore, the ECL layer can be remarkably extended by decreasing the co-reactant concentration, thus allowing the sequential imaging of cell-matrix and cell-cell junctions at the bottom and near the apical surface of cells, respectively. This strategy not only provides new insights into the ECL mechanisms but also promises wide applications of ECL microscopy in bioimaging.

Emergency Management of Medical Wastewater in Hospitals Specializing in Infectious Diseases: A Case Study of Huoshenshan Hospital, Wuhan, China.

Medical wastewater originating from hospitals specializing in infectious diseases pose a major risk to human and environmental health during pandemics. However, there have been few systematic studies on the management of this type of wastewater management. The function of the Huoshenshan Hospital as a designated emergency field hospital for the treatment of COVID-19 has provided lessons for the management measures of medical wastewater, mainly including: (1) Modern information technology, management schemes, and related standard systems provided the legislative foundation for emergency management of medical wastewater. (2) The three-tier prevention and control medical wastewater management system ensured the discharged wastewater met water quality standards, especially for the leak-proof sealed collection system of the first tier, and the biological and chemical treatment technology of the second tier. (3) The establishment of an effective three-tier medical wastewater quality monitoring accountability system. This system was particularly relevant for ensuring continuous data monitoring and dynamic analysis of characteristic indicators. (4) Information disclosure by government and public supervision promoted successful implementation of medical wastewater management and control measures. Public questionnaires (n = 212) further confirmed the effectiveness of information disclosure. The results of this study can act as methodological reference for the emergency management of wastewater in designated infectious disease hospitals under similar situations.