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Metal-organic frameworks (MOFs) exhibited huge application potential in electrochemical analysis field, how to facilely and effectively boost the electrochemical sensing activity of MOFs materials still face enormous challenges. In this work, core-shell Co-MOF (Co-TCA@ZIF-67) polyhedrons with hierarchical porosity was easily synthesized via simple chemical etching reaction by selecting thiocyanuric acid as the etching reagent. Benefiting from the introduction of mesopores and thiocyanuric acid/Co 2+ complex on the surface of ZIF-67 frameworks, the property and functions of the pristine ZIF-67 was seriously tailored. Compared with the pristine ZIF-67, the as-resulted Co-TCA@ZIF-67 nanoparticles displayed greatly enhanced physical adsorption capacity and electrochemical reduction activity toward the antibiotic drug furaltadone. As a result, a novel furaltadone electrochemical sensor with high sensitivity was fabricated. The linear detection range was from 50 nM to 5 μM with sensitivity of 110.40 μA -1  μM -1  cm -2 and detection limit of 12 nM. This work demonstrated chemical etching strategy is truly a facile and effective way to modify the electrochemical sensing performance of MOFs-based materials, and we believed the chemically etched MOFs materials will play a stronger role in terms of food safety and environmental conservation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background: Early stratification of disease progression remains one of the major challenges towards the post-coronavirus disease 2019 (COVID-19) era. The clinical relevance of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid load is debated due to the heterogeneity in patients' underlying health conditions. We determined the prognostic value of nasopharyngeal viral load dynamic conversion for COVID-19., Methods: The cycling threshold (Ct) values of 28,937 nasopharyngeal SARS-CoV-2 RT-PCRs were retrospectively collected from 3,364 COVID-19 patients during hospitalization and coordinated to the onset of disease progression. The ROC curve was utilized to determine the predictive performance of the rate of Ct value alteration between two consecutive RT-PCR runs within 48 h (ΔCt%) for disease transformation across patients with different COVID-19 severity and immune backgrounds, and further validated with 1,860 SARS-CoV-2 RT-PCR results from an independent validation cohort of 262 patients. For the 67 patients with severe COVID-19, Kaplan-Meier analysis was performed to evaluate the difference in survival between patients stratified by the magnitude of Ct value alteration between the late and early stages of hospitalization., Results: The kinetics of viral nucleic acid conversion diversified across COVID-19 patients with different clinical characteristics and disease severities. The ΔCt% is a clinical characteristic- and host immune status-independent indicator for COVID-19 progression prediction (AUC = 0.79, 95 % CI = 0.76 to 0.81), which outperformed the canonical blood test markers, including c-reactive protein (AUC = 0.57, 95 % CI = 0.53 to 0.61), serum amyloid A (AUC = 0.61, 95 % CI = 0.54 to 0.68), lactate dehydrogenase (AUC = 0.61, 95 % CI = 0.56 to 0.67), d-dimer (AUC = 0.56, 95 % CI = 0.46 to 0.66), and lymphocyte count (AUC = 0.62, 95 % CI = 0.58 to 0.66). Patients with persistent high SARS-CoV-2 viral load (an increase of mean Ct value < 50 %) during the first 3 days of hospitalization demonstrated a significantly unfavorable survival (HR = 0.16, 95 % CI = 0.04 to 0.65, P = 2.41 × 10 -3 )., Conclusions: Viral nucleic acid dynamics of SARS-CoV-2 eliminates the inter-patient variance of basic health conditions and therefore, can serve as a prognostic marker for COVID-19., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Herein, graphite nanosheets (GN) were first prepared through simple liquid-phase exfoliation of graphite powder in N, N-dimethylacetamide (DMAC). After then, ultrasmall Cu-based metal organic frame (HKUST-1) nanoparticles (less than 5 nm) were in-situ anchored on the surface of graphite nanosheets with high degree of dispersion. Due to the intrinsic structural advantages of the as-synthesized HKUST-1 nanoparticles decorated graphite nanosheets (HKUST-1/GN) hybrids, including superior electron transfer ability and the greatly enhanced adsorption property, HKUST-1/GN shows excellent electrochemical sensing performance toward DNA damage biomarker 8-hydroxy-2'-deoxyguanosine with fast detection speed (∼240 s), wide linear window (10 nM-1 μM), high sensitivity (346857 μA mM -1  cm -2 ), low detection limit (∼2.5 nM), and good reproducibility. As a result, a highly sensitive electrochemical sensing platform for the detection of DNA damage biomarker 8-hydroxy-2'-deoxyguanosine was fabricated basing the as-prepared HKUST-1/GN hybrids. What is more, the developed electrochemical method was successfully used for the detection of real samples and exhibited satisfied result., (Copyright © 2019. Published by Elsevier B.V.)

Objectives: Papillary thyroid carcinoma (PTC) accounts for 85% of thyroid carcinoma, which is the most common endocrine tumor. For the diagnosis of PTC, ultrasound-guided fine needle aspiration (FNA) with pathological evaluation is the standard test and BRAF V600E mutation is the most common molecular marker associated with the occurrence, progression and poor clinicopathological characteristics of PTC. However, because of the small amount of the tumor cells obtained by FNA for pathological evaluation or BRAF V600E mutation detection, more sensitive and accurate methods are required. Our study aimed to investigate the performance of droplet digital PCR (ddPCR) in detecting BRAF V600E mutation in FNA samples from PTC patients., Methods: One hundred and sixty suspected thyroid cancer patients were enrolled, including 146 PTC patients, 2 follicular thyroid carcinoma (FTC) and 12 benign patients, identified by FNA biopsy according to the NCCN clinical practice guidelines of Thyroid Carcinoma. ddPCR and amplification-refractory mutation system (ARMS, AmoyDx) were used to detect BRAFV600E mutation and the results were compared., Results: ddPCR had high reproducibility (CV0.1% = 22.82% and CV10% = 4.85%) and the detection sensitivity can reach 1–2 copies/μl (0.01%). Among the 160 patients, 128 BRAF V600E mutations were detected, including 4 ARMS negative patients and 3 benign cases [corrected]., Conclusions: Our results demonstrated that ddPCR could be used in detecting BRAF V600E mutation from FNA fluid samples with higher sensitivity and accuracy than ARMS., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Bleeding and thrombosis represent common complications in myeloproliferative neoplasms (MPN) and significantly contribute to morbidity and mortality. Molecular markers, including CALR mutations, were considered not only as diagnostic markers, but also as risk factors for bleeding and thrombosis associated with MPN, especially for patients in remote primary hospitals. We sought to develop an easy-to-use assay for the rapid detection of CALR type 1 (CALR-1) and type 2 (CALR-2) mutations in Philadelphia chromosome-negative MPN patients. Peptide nucleic acid-locked nucleic acid (PNA-LNA) clamping loop-mediated isothermal amplification (LAMP) assays were established, which were integrated into a centrifugal compact disc (CD) microfluidic platform. A total of 158 clinical blood samples were tested simultaneously by this microfluidic platform and an in-house real time PCR assay. The detection performance of the LAMP arrays was validated and conflicting results were identified by Sanger sequencing. The results suggested that the LAMP methods we developed exhibited good sensitivity, specificity, and precision. By real time fluorescence assay the detection limit for CALR-1 and CALR-2 mutations could reach as low as 1% and 0.5% respectively, and 10% and 5% respectively by visual method. There were no nonspecific background amplifications among different detection systems. For the CALR-1 and CALR-2 LAMP detection systems, intra-batch CV values of 1% mutated plasmid were 10.56% and 10.51% respectively, and the inter-batch CV values were 19.55% and 18.39%, respectively. The products were all analyzed by melting curve analysis and electrophoresis followed by Sanger sequencing analysis, which were consistent with the database sequences. The microfluidic platform could complete rapid detection of CALR-1/2 mutations within 60 min. The results of clinical samples detected by our CD-like microfluidic chipLAMP assay and rtPCR assay suggested that 133 samples were CALR wild type, 15 were CALR-1 mutation type, and 9 were CALR-2 mutation type. The correlation coefficient value (Kendall's tau&#95;b) of the two assays was 0.99. Interestingly, by the newly established detection platform, we were surprised to find that one patient of Chinese origin harbored both CALR-1 and CALR-2 mutations. This result was verified by Sanger sequencing analysis. The LAMP detection systems developed herein displayed good sensitivity, specificity, and stability. Additionally, the detection results could be directly judged by color changes of the reaction systems without any auxiliary equipment. Thus, the platform we developed has the potential of being widely used in remote and economically undeveloped areas in the future., (Copyright © 2018 Elsevier B.V. All rights reserved.)

miR-301 is localized in the first intron of ska2, whose function has not been clarified. Here, a new circuit model in which intronic miR-301 regulates the transcription and function of its host gene through a feedback mechanism has been described. Our results showed that blocking of miR-301 in A549 cells leads to a decrease in the expression of the host gene, ska2. Further analysis showed that miR-301 targets MEOX2 to affect the ERK/CREB pathway. CREB directly regulates the expression of the host gene, ska2. In addition, the inhibition of miR-301 or ska2 resulted in an increase of the mitotic index and a decrease in colony formation in soft agar, which may be related to lung tumorigenesis., ((c) 2010 Elsevier Inc. All rights reserved.)

RNA chaperones are defined as proteins that aid in the process of RNA folding by processing misfolding or by resolving misfolded structures. Although RNA chaperones are ubiquitous and abundant in all living organisms and viruses, there are no any reports that a cytokine has such RNA chaperone activity. Here, we demonstrate for the first time that recombinant human tumor necrosis factor alpha (rhTNF-alpha), a well-known cytokine, has RNA chaperone activity in vitro. rhTNF-alpha binds random 68 nt RNAs strongly at the minimal concentration of 10 microM with a broad sequence specificity. Our results also show that rhTNF-alpha facilitates annealing and strand exchange, and promotes the cleavage of a 17-nucleotide substrate S by hammerhead ribozyme HH16. The role of TNF-alpha as an RNA chaperone in vivo is not clear, but we propose that TNF-alpha may play an important role as an RNA chaperone during the process of some infectious and inflammatory diseases.