Dual electrochemical signal "signal-on-off" sensor based on CHA-Td-HCR and CRISPR-Cas12a for MUC1 detection.

Mucin 1 (MUC1) is frequently overexpressed in various cancers and is essential for early cancer detection. Current methods to detect MUC1 are expensive, time-consuming, and require skilled personnel. Therefore, developing a simple, sensitive, highly selective MUC1 detection sensor is necessary. In this study, we proposed a novel "signal-on-off" strategy that, in the presence of MUC1, synergistically integrates catalytic hairpin assembly (CHA) with DNA tetrahedron (Td)-based nonlinear hybridization chain reaction (HCR) to enhance the immobilization of electrochemically active methylene blue (MB) on magnetic nanoparticles (MNP), marking the MB signal "on". Concurrently, the activation of CRISPR-Cas12a by isothermal amplification products triggers the cleavage of single-stranded DNA (ssDNA) at the electrode surface, resulting in a reduction of MgAl-LDH@Fc-AuFe-MIL-101 (containing ferrocene, Fc) on the electrode, presenting the "signal-off" state. Both MB and MgAl-LDH@Fc-AuFe-MIL-101 electrochemical signals were measured and analyzed. Assay parameters were optimized, and sensitivity, stability, and linear range were assessed. Across a concentration spectrum of MUC1 spanning from 10 fg/mL to 100 ng/mL, the MB and MgAl-LDH@Fc-AuFe-MIL-101 signals were calibrated with each other, demonstrating a "signal-on-off" dual electrochemical signaling pattern. This allows for the precise and quantitative detection of MUC1 in clinical samples, offering significant potential for medical diagnosis.

Electrochemical-Fluorescent Bimodal Biosensor Based on Dual CRISPR-Cas12a Multiple Cascade Amplification for ctDNA Detection.

Circulating tumor DNA (ctDNA) is a critical biomarker for early tumor detection. However, accurately quantifying low-abundance ctDNA in human serum remains a significant challenge. To address this challenge, we introduce a bimodal biosensor tailored for detecting the epidermal growth factor receptor (EGFR) mutation L858R in specific nonsmall cell lung cancer (NSCLC) patients. This biosensor utilizes dual CRISPR-Cas12a systems to quantify the target via fluorescence and electrochemical signals. In our system, the EGFR L858R exhibits resistance to digestion by the restriction enzyme MscI, which activates the first CRISPR-Cas12a protein and inhibits the binding of magnetic beads with fluorescein (FAM)-labeled hybridization chain reaction (HCR) products, thereby reducing the fluorescence signal. This activation also inhibits the cleavage activity of the second CRISPR-Cas12a protein, allowing the electrode to sustain a higher electrochemical signal from nanomaterials. The wild-type EGFR (wt EGFR) produces the opposite effect. Consequently, the concentration of EGFR L858R can be accurately quantified and verified using both fluorescence and electrochemical signals. The biosensor offers a dynamic detection ranging from 10 fM to 1 µM, with a detection limit of 372 aM. It demonstrates excellent specificity, reproducibility, stability, and recovery rates. Moreover, the sensor's enhanced analytical sensitivity highlights its critical role in biosensing applications and early disease diagnosis.

Ultrasensitive and label-free electrochemical immunosensor for the detection of the ovarian cancer biomarker CA125 based on CuCo-ONSs@AuNPs nanocomposites.

Cancer antigen 125 (CA125) is pivotal as a tumor marker in early ovarian cancer prevention and diagnosis. In this work, we introduced an ultrasensitive label-free electrochemical immunosensor tailored for CA125 detection, leveraging nanogold-functionalized copper-cobalt oxide nanosheets (CuCo-ONSs@AuNPs) as nanocomposites. For the inaugural application, copper-cobalt oxide nanosheets delivered the requisite DPV electrochemical response for the immunosensors. Their large specific surface area and commendable electrical conductivity amplify electron transfer and enable significant gold nanoparticle loading. Concurrently, AuNPs offer a plethora of active sites, facilitating easy immobilization of biomolecules via the bond between amino groups and AuNPs. We employed scanning electron microscopy, transmission electron microscopy, and x-ray photoelectron spectroscopy to characterize the nanomaterials' surface morphology and elemental composition. The electrochemical sensor response signals were ascertained using differential pulse voltammetry. Under optimal conditions, the immunosensor exhibited a linear detection range from 1×10-7 U/mL to 1×10-3 U/mL and a detection limit of 3.9×10-8 U/mL (S/N=3). The proposed label-free electrochemical immunosensor furnishes a straightforward, dependable, and sensitive approach for CA125 quantification and stands as a promising method for clinical detection of other tumor markers.

Meta-analysis of pulsed-field ablation versus cryoablation for atrial fibrillation.

PURPOSE: The available data on the treatment strategy of pulsed field ablation (PFA) for patients with atrial fibrillation (AF) is limited. This study aims to provide a comparative analysis of the efficacy, safety, and procedural efficiency between PFA and cryoballoon ablation (CBA) for AF. METHODS: We conducted a comprehensive search of the EMBASE, PubMed, Cochrane Library, and ClinicalTrials.gov databases to identify trials comparing PFA with CBA for AF from their inception until December 2023. The odds ratio (OR) and mean difference (MD), along with a 95% confidence interval (CI), were utilized as measures of treatment effect. RESULTS: The analysis included 15 eligible trials with a total enrollment of 1880 patients. No significant differences were found in recurrent atrial arrhythmia (OR 0.83, 95% CI 0.64, 1.07) or periprocedural complications (OR 0.78, 95% CI 0.46, 1.30) between the two ablation techniques examined in this study. However, the PFA technique demonstrated a significantly shorter procedure time (MD -7.17, 95% CI -13.60, -0.73), but a longer fluoroscopy time (MD 2.53, 95% CI 0.87, 4.19). Similarly, PFA was found to be significantly associated with a decreased incidence of phrenic nerve palsy (OR 0.20, 95% CI 0.07, 0.59), but an increased incidence of cardiac tamponade (OR 4.07, 95% CI 1.15, 14.39). Moreover, there was a significantly higher release of troponin with PFA compared to CBA (MD 470.28, 95% CI 18.89, 921.67), while the increase in S100 protein and heart rate was significantly lower with PFA than with CBA (MD -64.41, 95% CI -105.46, -17.36), (MD -8.76, 95% CI -15.12, -2.40). CONCLUSION: The utilization of PFA provides a safer, time-saving, and tissue-specific procedure compared to CBA, while maintaining comparable success rates. This has the potential to enhance procedural efficiency and optimize resource utilization in clinical practice. These findings underscore the feasibility and promise of PFA as an alternative technique for PVI in patients with AF.

Sandwich-type immunosensor based on aminated 3D-rGOF-NH2 and CMK-3-Fc-MgAl-LDH multilayer nanocomposites for detection of CA125.

Cancer antigen 125 (CA125)1 is the most important biological screening indicator used to monitor epithelial ovarian cancers, and it plays a vital role in distinguishing ovarian cancers from benign diseases. Biosensors show great potential in the analysis and detection of disease markers. In this study, we designed electrochemical sensors based on three-dimensional amino-functionalized reduced graphene oxide (3D-rGOF-NH2),2 MgAl layered double hydroxide nanocomposites containing ordered mesoporous carbon (CMK-3),3 and ferrocene carboxylic acids（Fc-COOH）4for the detection of CA125. 3D-rGOF-NH2 possesses good conductivity, a large surface area, and high porosity, enabling more immobilized nanoparticles to be deposited on its surface with excellent stability. CMK-3@Fc@MgAl-LDH nanocomposite was used as a carrier to enhance the immobilization of antibodies and the loading of Fc, conductors to enhance conductivity, and enhancers to gradually amplify the signal of Fc. The surface morphology, elemental composition, and surface groups of the materials were characterized using scanning electron microscopy (SEM),5 transmission electron microscopy (TEM),6 and X-ray diffraction (XRD)7 techniques. The response signal of the electrochemical sensor was measured by DPV. Under the optimal conditions, the electrochemical sensor obtained a linear detection range of 0.01 U/mL-100 U/mL with a detection limit of 0.00417 U/mL.

Overcoming Multidrug Resistance by Base-Editing-Induced Codon Mutation.

Multidrug resistance (MDR) is the main obstacle in cancer chemotherapy. ATP binding cassette (ABC) transporters on the MDR cell membrane can transport a wide range of antitumor drugs out of cells, which is one of the main causes of MDR. Therefore, disturbing ABC transporters becomes the key to reversing MDR. In this study, we implement a cytosine base editor (CBE) system to knock out the gene encoding ABC transporters by base editing. When the CBE system works in MDR cells, the MDR cells are manipulated, and the genes encoding ABC transporters can be inactivated by precisely changing single in-frame nucleotides to induce stop (iSTOP) codons. In this way, the expression of ABC efflux transporters is reduced and intracellular drug retention is significantly increased in MDR cells. Ultimately, the drug shows considerable cytotoxicity to the MDR cancer cells. Moreover, the substantial downregulation of P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) implies the successful application of the CBE system in the knockout of different ABC efflux transporters. The recovery of chemosensitivity of MDR cancer cells to the chemotherapeutic drugs revealed that the system has a satisfactory universality and applicability. We believe that the CBE system will provide valuable clues for the use of CRISPR technology to defeat the MDR of cancer cells.

Household solid fuel use and peak expiratory flow in middle-aged and older adults in China: A large cohort study (2011-2015).

Indoor air pollution caused by solid fuel use in cooking and heating in China is common. The relationship between household solid fuel use and peak expiratory flow (PEF) in middle-aged and older adults in China has not been clarified. The aim of this study was to assess the relationship between long-term household solid fuel use (clean for both cooking and heating, solid for either cooking or heating, and solid for both cooking and heating) and PEF changes in middle-aged and older adults using a nationally representative prospective cohort. Covariance analysis was used to compare PEF changes in different indoor air pollution exposure groups. Separate analysis of cooking and heating as well as sub-group analyses by age, sex and smoking status were conducted, linear mixed growth model analysis was used to evaluate the association between cooking fuel type and PEF. A total of 6818 participants were enrolled in the cohort analysis. Results revealed that solid fuel use in cooking and heating separately or conjointly were associated with reduced PEF (solid fuel use in cooking: least square mean [LSM] = 19.9, 95% confidence interval [CI]: 11.5-28.2, P = 0.03; solid fuel use in heating: LSM = 19.4, 95% CI:11.2-27.5, P = 0.04; both solid fuel use: LSM = 17.6, 95% CI: 9.3-25.9, P for trend <0.0001), especially in participants aged >65 years (LSM = -9.22, 95% CI: 27.9-69.52, P for trend <0.0001), females (LSM = -6.41, 95% CI: 19.12-6.30, P for trend <0.0001) and current or former smokers (LSM = -21.55, 95% CI: 36.14 to -6.97, P < 0.02). Compared to that of participants using clean fuels for cooking, PEF of participants using solid fuels were decreased by 3.5 l/min per 2 years over a 4-year follow-up. This cohort study highlights the adverse effects of indoor air pollution on lung function in middle aged and older adults in China.

A telomerase-responsive nanoprobe with theranostic properties in tumor cells.

Multidrug resistance (MDR) is the main cause of treatment failure in clinical cancer chemotherapy due to the presence of P-glycoproteins (P-gp), which widely exist in stubborn drug-resistant tumor membranes and actively pump drugs from inside the tumor cell to the outside. In this study, we report a novel telomerase-responsive nanoprobe with theranostic properties for inhibiting P-gp expression and reversing MDR by gene silencing. This nanoprobe is composed of an AuNP assembled with telomerase primer, antisense oligonucleotide (ASO), and doxorubicin (Dox). When the designed nanoprobe is uptaken by the MDR cancer cells, the Dox and ASO are specifically released due to the extension of telomerase primer triggered by telomerase. The released ASO specifically hybridizes with multidrug resistance 1 (MDR1) mRNA sequence, which encodes the P-gp. As a result, the expression of P-gp is inhibited and the efflux of Dox is prevented with reduced MDR in cancerous cells. The results demonstrate that the nanoprobe based on telomerase switching for drug release and gene silencing, can both target cancer cells for delivering drugs and overcome the effect of efflux pumps. This work presents a novel paradigm for theranostics of MDR cancer and enhances the efficacy of chemotherapeutics.