SERS microfluidic chip integrated with double amplified signal off-on strategy for detection of microRNA in NSCLC.

In this work, based on Fe3O4@AuNPs and double amplified signal Off-On strategy, a simple and sensitive SERS microfluidic chip was constructed to detect microRNA associated with non-small cell lung cancer (NSCLC). Fe3O4@AuNPs have two advantages of SERS enhanced and magnetic adsorption, the introduction of microfluidic chip can realize double amplification of SERS signal. First, the binding of complementary ssDNA and hpDNA moved the Raman signaling molecule away from Fe3O4@AuNPs, at which point the signal was turned off. Second, in the presence of the target microRNA, they were captured by complementary ssDNA and bound to them. HpDNA restored the hairpin conformation, the Raman signaling molecule moved closer to Fe3O4@AuNPs. At this time, the signal was turned on and strong Raman signal was generated. And last, through the magnetic component of SERS microfluidic chip, Fe3O4@AuNPs could be enriched to realize the secondary enhancement of SERS signal. In this way, the proposed SERS microfluidic chip can detect microRNA with high sensitivity and specificity. The corresponding detection of limit (LOD) for miR-21 versus miR-125b was 6.38 aM and 7.94 aM, respectively. This SERS microfluidic chip was promising in the field of early detection of NSCLC.

LoC-SERS platform for rapid and sensitive detection of colorectal cancer protein biomarkers.

Colorectal cancer (CRC) remains a significant contributor to the global mortality rate, and a single biomarker cannot meet the specificity required for CRC screening. To this end, we developed a multiplexed, pump-free surface-enhanced Raman scattering (SERS) microfluidic chip (LoC-SERS) using a one-step recognition release mechanism; the aptamer-functionalized novel Au nanocrown array (AuNCA) was used as the detection element embedded in the detection zone of the platform for rapid and specific detection of protein markers in multiple samples simultaneously. Here, the corresponding aptamer specifically captured the protein marker, causing the complementary strand of the aptamer carrying the Raman signal molecule to be shed, reducing the SERS signal. Based on this platform, sensitive and specific detection of the target can be accomplished within 15 min with detection limits of 0.031 pg/mL (hnRNP A1) and 0.057 pg/mL (S100P). Meanwhile, the platform was consistent with ELISA results when used to test clinical. By substituting different aptamers, this platform can provide a new solution for the rapid and sensitive detection of protein markers, which has promising applications in future disease detection.

A comparative transcriptome analysis of how shrimp endure and adapt to long-term symbiosis with Enterocytozoon hepatopenaei infection.

Enterocytozoon hepatopenaei (EHP) is a prevalent microsporidian pathogen responsible for hepatopancreatic microsporidiosis (HPM) in Litopenaeus vannamei. This infection not only leads to slowed growth in shrimp abut aslo inflicts substantial economic losses in the global aquaculture industry. However, the molecular mechanisms by which EHP influences the host during various infection stages remain unclear. This study employed comparative transcriptomics to examine the effects of EHP infection on Litopenaeus vannamei between early and late stage of infection groups. Utilizing transcriptomic approaches, we identified differentially expressed genes (DEGs) with notable biological significance through the COG, GO, KEGG, GSEA, and Mufzz time-series methodologies. The results reveal that EHP infection considerably influences host gene expression, with marked differences between early and late infection across distinct timeframes. Key processes such as detoxification, cell apoptosis, and lipid metabolism are pivotal during host-parasite interactions. Hexokinase and phosphatidic acid phosphatase emerge as key factors enabling invasion and sustained effects. Cytochrome P450 and glucose-6-phosphate dehydrogenase could facilitate infection progression. EHP significantly impacts growth, especially through ecdysteroids and 17ß-estradiol dehydrogenase. By delineating stage-specific effects, we gain insights into interaction between EHP and Litopenaeus vannamei, showing how intracellular pathogens reprogram host defenses into mechanisms enabling long-term persistence. This study provides a deeper understanding of host-pathogen dynamics, emphasizing the interplay between detoxification, metabolism, immunity, apoptosis and growth regulation over the course of long-term symbiosis.

Simple and Ultrasensitive Detection of Glioma-Related ctDNAs in Mice Serum by SERS-Based Catalytic Hairpin Assembly Signal Amplification Coupled with Magnetic Aggregation.

Purpose: Circulating tumor DNA (ctDNA) is more representative and accurate than biopsy and is also conducive to dynamic monitoring, facilitating accurate diagnosis and prognosis of glioma. Therefore, the present study aimed to establish and validate a novel amplified method for the detection of IDH1 R132H and BRAF V600E, which were associated with the genetic diagnosis of glioma. Patients and Methods: A dual-signal amplification method based on magnetic aggregation and catalytic hairpin assembly (CHA) was constructed for the simultaneous detection of ctDNAs. When target ctDNAs are present, the CHA reaction is initiated and leads to the assembly of Au-Ag nanoshuttles (Au-Ag NSs) onto magnetic beads (MBs). Further enrichment of MBs under an external magnetic field facilitated the dual-signal amplification of SERS. Results: The limit of detection (LOD) for IDH1 R132H and BRAF V600E in serum was as low as 6.01 aM and 5.48 aM. The reproducibility and selectivity of the proposed SERS analysis platform was satisfactory. Finally, the platform was applied to quantify IDH1 R132H and BRAF V600E in the serum of subcutaneous-tumor­bearing nude mice, and the results obtained by SERS were consistent with those from quantitative real-time polymerase chain reaction (qRT-PCR). Conclusion: The present study showed that the dual-signal amplification method is a simple and ultrasensitive strategy for gliomas-associated ctDNAs detection, which is crucial for early diagnosis and dynamic monitoring.

A polyaniline functionalized NiFeP nanosheet array-based electrochemical immunosensor using Au/Cu2O nanocubes as a signal amplifier for the detection of SARS-CoV-2 nucleocapsid protein.

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which emerged as a novel pathogen in 2019. The virus is responsible for a severe acute respiratory syndrome outbreak, affecting the respiratory system of infected individuals. COVID-19 is a super amplifier of basic diseases, and the disease with basic diseases is often more serious. Controlling the spread of the COVID-19 pandemic relies heavily on the timely and accurate detection of the virus. To resolve the problem, a polyaniline functionalized NiFeP nanosheet array-based electrochemical immunosensor using Au/Cu2O nanocubes as a signal amplifier is fabricated for the detection of SARS-CoV-2 nucleocapsid protein (SARS-CoV-2 NP). Polyaniline (PANI) functionalized NiFeP nanosheet arrays are synthesized as an ideal sensing platform for the first time. PANI is coated on the surface of NiFeP by electropolymerization to enhance biocompatibility, beneficial for the efficient loading of the capture antibody (Ab1). Significantly, Au/Cu2O nanocubes possess excellent peroxidase-like activity and exhibit outstanding catalytic activity for the reduction of H2O2. Therefore, Au/Cu2O nanocubes combine with a labeled antibody (Ab2) through the Au-N bond to form labeled probes, which can effectively amplify current signals. Under optimal conditions, the immunosensor for the detection of SARS-CoV-2 NP shows a wide linear range of 10 fg mL-1-20 ng mL-1 and a low detection limit of 1.12 fg mL-1 (S/N = 3). It also exhibits desirable selectivity, repeatability, and stability. Meanwhile, the excellent analytical performance in human serum samples confirms the practicality of the PANI functionalized NiFeP nanosheet array-based immunosensor. The electrochemical immunosensor based on the Au/Cu2O nanocubes as a signal amplifier demonstrates great potential for application in the personalized point-of-care (POC) clinical diagnosis.

LoC-SERS Platform Integrated with the Signal Amplification Strategy toward Parkinson's Disease Diagnosis.

Multiplexed detection of Parkinson's disease (PD) biomarkers is of great significance for early diagnosis and personalized treatment. In this study, we fabricated a robust surface-enhanced Raman scattering-enabled lab-on-a-chip (LoC-SERS) platform for simultaneous quantification of α-synuclein, phosphorylated tau protein 181, osteopontin, and osteocalcin. Herein, the antibody-DNA conjugate was designed to introduce the catalytic hairpin self-assembly (CHA) amplification into the protein detection. Au nano-stars (AuNSs) modified with Raman reporter molecules and hairpin-structure DNA 1 were applied as the SERS nanotags. Au-coated silicon nanocone array (Au/SiNCA) fabricated based on the maskless plasma etching-prepared high-density Si nanocone array (SiNCA) and surface ion sputtering was used as the capture substrate after the modification of hairpin-structure DNA 2. Benefitting from the antibody-DNA conjugate-induced CHA amplification, numerous AuNSs can be connected to the Au/SiNCA surface, which significantly amplify the plasmonic coupling effect for ultrasensitive SERS detection, and the limit of detection was less than the pg/mL level. The application of highly uniform Au/SiNCA and antibody-DNA conjugate endows the LoC-SERS platform excellent analytical performance, including superior reproducibility, satisfactory universality, and high sensitivity. In addition, a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mice model was established, and satisfactory results were obtained in real sample analysis with the LoC-SERS platform, which may be enlightening for exploiting protein biomarkers in PD monitoring.

Blocking postsynaptic density-93 binding to C-X3-C motif chemokine ligand 1 promotes microglial phenotypic transformation during acute ischemic stroke.

We previously reported that postsynaptic density-93 mediates neuron-microglia crosstalk by interacting with amino acids 357-395 of C X3 C motif chemokine ligand 1 (CX3CL1) to induce microglia polarization. More importantly, the peptide Tat-CX3CL1 (comprising amino acids 357-395 of CX3CL1) disrupts the interaction between postsynaptic density-93 and CX3CL1, reducing neurological impairment and exerting a protective effect in the context of acute ischemic stroke. However, the mechanism underlying these effects remains unclear. In the current study, we found that the pro-inflammatory M1 phenotype increased and the anti-inflammatory M2 phenotype decreased at different time points. The M1 phenotype increased at 6 hours after stroke and peaked at 24 hours after perfusion, whereas the M2 phenotype decreased at 6 and 24 hours following reperfusion. We found that the peptide Tat-CX3CL1 (357-395aa) facilitates microglial polarization from M1 to M2 by reducing the production of soluble CX3CL1. Furthermore, the a disintegrin and metalloprotease domain 17 (ADAM17) inhibitor GW280264x, which inhibits metalloprotease activity and prevents CX3CL1 from being sheared into its soluble form, facilitated microglial polarization from M1 to M2 by inhibiting soluble CX3CL1 formation. Additionally, Tat-CX3CL1 (357-395aa) attenuated long-term cognitive deficits and improved white matter integrity as determined by the Morris water maze test at 31-34 days following surgery and immunofluorescence staining at 35 days after stroke, respectively. In conclusion, Tat-CX3CL1 (357-395aa) facilitates functional recovery after ischemic stroke by promoting microglial polarization from M1 to M2. Therefore, the Tat-CX3CL1 (357-395aa) is a potential therapeutic agent for ischemic stroke.

Rapid determination of SARS-CoV-2 nucleocapsid proteins based on 2D/2D MXene/P-BiOCl/Ru(bpy)32+ heterojunction composites to enhance electrochemiluminescence performance.

At the end of 2019, the novel coronavirus disease 2019 (COVID-19), a cluster of atypical pneumonia caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been known as a highly contagious disease. Herein, we report the MXene/P-BiOCl/Ru(bpy)32+ heterojunction composite to construct an electrochemiluminescence (ECL) immunosensor for SARS-CoV-2 nucleocapsid protein (CoVNP) determination. Two-dimensional (2D) material ultrathin phosphorus-doped bismuth oxychloride (P-BiOCl) is exploited and first applied in ECL. 2D architectures MXene not only act as "soft substrate" to improve the properties of P-BiOCl, but also synergistically work with P-BiOCl. Owing to the inimitable set of bulk and interfacial properties, intrinsic high electrochemical conductivity, hydrophilicity and good biocompatible of 2D/2D MXene/P-BiOCl/Ru(bpy)32+, this as-exploited heterojunction composite is an efficient signal amplifier and co-reaction accelerator in the presence of tri-n-propylamine (TPA) as a coreactant. The proposed MXene/P-BiOCl/Ru(bpy)32+-TPA system exhibits a high and stable ECL signal and achieves ECL emission quenching for "signal on-off" recognition of CoVNP. Fascinatingly, the constructed ECL biosensor towards CoVNP allows a wide linear concentration range from 1 fg/mL to 10 ng/mL and a low limit of detection (LOD) of 0.49 fg/mL (S/N = 3). Furthermore, this presented strategy sheds light on designing a highly efficient ECL nanostructure through the combination of 2D MXene architectures with 2D semiconductor materials in the field of nanomedicine. This ECL biosensor can successfully detect CoVNP in human serum, which can promote the prosperity and development of diagnostic methods of SARS-CoV-2.

Serum-based surface-enhanced Raman spectroscopy combined with PCA-RCKNCN for rapid and accurate identification of lung cancer.

Early and precise diagnosis of lung cancer is critical for a better prognosis. However, it is still a challenge to develop an effective strategy for early precisely diagnose and effective treatments. Here, we designed a label-free and highly accurate classification serum analytical platform for identifying mice with lung cancer. Specifically, the microarray chip integrated with Au nanostars (AuNSs) array was employed to measure the surface-enhanced Raman scattering (SERS) spectra of serum of tumor-bearing mice at different stages, and then a recognition model of SERS spectra was constructed using the principal component analysis (PCA)-representation coefficient-based k-nearest centroid neighbor (RCKNCN) algorithm. The microarray chip can realize rapid, sensitive, and high-throughput detection of SERS spectra of serum. RCKNCN based on the PCA-generated features successfully differentiated the SERS spectra of serum of tumor-bearing mice at different stages with a classification accuracy of 100%. The most prominent spectral features for distinguishing different stages were captured in PCs loading plots. This work not only provides a practical SERS chip for the application of SERS technology in cancer screening, but also provides a new idea for analyzing the feature of serum at the spectral level.

A capillary-driven LoC-SERS device integrated with catalytic hairpin assembly amplification technology for NSCLC-related biomarkers detection.

In this study, we apply catalytic hairpin assembly (CHA) as the signal amplification strategy for the quantification of carcinoembryonic antigen (CEA) and cytokeratin fragment antigen 21-1 (CYFRA21-1) with a surface-enhanced Raman scattering (SERS) microfluidic chip (LoC-SERS) as the carrier. Herein, antibody-DNA conjugates are designed to assist the application of CHA amplification in protein detection. In the presence of protein biomarkers, antibody-DNA conjugates can specifically bind to the target proteins, forming the antigen@antibody-DNA conjugates. The terminal free part of the DNA on the conjugates can trigger the CHA events to connect SERS nanotags to capture nanoprobes. Then, micro-magnet can gather the CHA products in a rectangular chamber, resulting in the aggregation of SERS nanotags, which can ultimately generate abundant "hot spots" for SERS signal enhancement. Using this strategy, CEA and CYFRA21-1 can be successfully determined with a limit of detection (LOD) as low as pg mL-1, much lower than recently reported methods. Meanwhile, a non-small cell lung cancer (NSCLC)-xenografted mouse model was established, and SERS was applied to analyze the expression level of CEA and CYFRA21-1 in tumorigenesis and development. The comparison between SERS results and those of the ELISA method demonstrated a high degree of consistency, suggesting that the proposed CHA-assisted LoC-SERS device has satisfying accuracy. Thus, introducing the CHA strategy via the design of antibody-DNA conjugates opens new gates to ultra-sensitive and specific SERS detection of protein biomarkers.

A microfluidic chip using Au@SiO2 array-based highly SERS-active substrates for ultrasensitive detection of dual cervical cancer-related biomarkers.

In this work, a microfluidic chip using Au@SiO2 array-based highly active SERS substrates was developed for quantitative detection of squamous cell carcinoma antigen (SCCA) and carcinoembryonic antigen (CEA) associated with cervical cancer. The chip consisted of six functional units with pump-free design, enabling parallel detection of multiple samples in an automatic manner without external pumps and improving the portability. Ag nanocubes (AgNCs) were labeled with Raman reporters and coupled with antibodies (labeling) to prepare SERS tags, while the Au nanoparticle-modified SiO2 microsphere (Au@SiO2) array was conjugated with antibodies (coating) to generate the highly SERS-active capturing substrate. In the presence of target biomarkers, they were captured by SERS tags and capturing substrate, resulting in the formation of "sandwich" structures which were trapped in the detection chamber. As the immune reaction proceeded, a large number of "hot spots" were generated by the proximity of the Au@SiO2 array substrate and AgNCs, greatly amplifying SERS signals. With this chip, the limits of detection of the SCCA and CEA levels in human serum were estimated to be as low as 0.45 pg mL-1 and 0.36 pg mL-1, respectively. Furthermore, the good selectivity and reproducibility of this chip were confirmed. Finally, clinical serum samples were analyzed by this chip, and the outcomes were consistent with those of enzyme-linked immunosorbent assay (ELISA). Thus, the proposed microfluidic chip can be potentially applied for the clinical diagnosis of cervical cancer.

Highly sensitive and simultaneous detection of ctDNAs related to non-small cell lung cancer in serum using a catalytic hairpin assembly strategy in a SERS microfluidic chip.

Circulating tumor DNA (ctDNA) is an ideal biomarker for cancer diagnosis based on liquid biopsy, so there is an urgent need for developing an efficient, rapid, and ultrasensitive detection method to meet clinical needs. In this paper, a novel surface-enhanced Raman scattering (SERS) microfluidic chip combined with a catalytic hairpin assembly (CHA) was proposed to detect two non-small cell lung cancer (NSCLC)-related ctDNA (TP53 and PIK3CA-Q546K) simultaneously. The chip consists of six channels for parallel detection. In the reaction region, the CHA reaction between HP1 of the SERS probe and HP2 of the capture substrate was triggered by ctDNAs to form HP1-HP2 duplexes. As the reaction proceeds, more and more SERS probes are captured on the substrate. The gathered reaction products continuously form a lot of hot spots, which greatly enhance the SERS signal. This reaction was completed within 5 minutes. Through this method, the detection limits of TP53 and PIK3CA-Q546K in human serum were as low as 2.26 aM and 2.34 aM, respectively. The microfluidic chip also exhibited high specificity, reproducibility and stability. The clinical feasibility of the SERS microfluidic chip was verified by analyzing the serum samples of healthy subjects and NSCLC patients. The reliability of the experimental results was verified by the qRT-PCR test. The constructed SERS-based analytical micro-platform has great potential in dynamic monitoring of cancer staging and could be used as a clinical tool for early cancer screening.

A pump-free and high-throughput microfluidic chip for highly sensitive SERS assay of gastric cancer-related circulating tumor DNA via a cascade signal amplification strategy.

Circulating tumour DNA (ctDNA) has emerged as an ideal biomarker for the early diagnosis and prognosis of gastric cancer (GC). In this work, a pump-free, high-throughput microfluidic chip coupled with catalytic hairpin assembly (CHA) and hybridization chain reaction (HCR) as the signal cascade amplification strategy (CHA-HCR) was developed for surface-enhanced Raman scattering (SERS) assays of PIK3CA E542K and TP53 (two GC-related ctDNAs). The chip consisted of six parallel functional units, enabling the simultaneous analysis of multiple samples. The pump-free design and hydrophilic treatment with polyethylene glycol (PEG) realized the automatic flow of reaction solutions in microchannels, eliminating the dependence on external heavy-duty pumps and significantly improving portability. In the reaction region of the chip, products generated by target-triggered CHA initiated the HCR, forming long nicked double-stranded DNA (dsDNA) on the Au nanobowl (AuNB) array surface, to which numerous SERS probes (Raman reporters and hairpin DNA-modified Cu2O octahedra) were attached. This CHA-HCR strategy generated numerous active "hot spots" around the Cu2O octahedra and AuNB surface, significantly enhancing the SERS signal intensity. Using this chip, an ultralow limit of detection (LOD) for PIK3CA E542K (1.26 aM) and TP53 (2.04 aM) was achieved, and the whole process was completed within 13 min. Finally, a tumour-bearing mouse model was established, and ctDNA levels in mouse serum at different stages were determined. To verify the experimental accuracy, the gold-standard qRT-PCR assay was utilized, and the results showed a high degree of consistency. Thus, this rapid, sensitive and cost-effective SERS microfluidic chip has potential as an ideal detection platform for ctDNA monitoring.

A two-dimensional G-CoP/N,P-co-doped carbon nanowire electrode for the simultaneous determination of hydroquinone and catechol in domestic wastewater.

Hydroquinone (HQ) and catechol (CC) are important chemical raw materials in the modern industry, unfortunately, which are also high toxic phenolic pollutants. So how to achieve highly sensitive and selective determination HQ and CC is the challenge we face. In the present work, we report a facile strategy to obtain nitrogen and phosphorous co-doped glucose-derived carbon coated CoP nanowires (G-CoP/N,P-C NWs), in which nitrilotriacetic acid (NTA) was as the chelating reagent, glucose was as carbon source, and the precursors were subsequently experienced carbonization and phosphorization process. G-CoP/N,P-C NWs can shorten the distance of the electron transport and expand the reaction area, showing the intriguing electronic conductivity and electrocatalytic abilities. An electrochemical phenolic sensor based on G-CoP/N,P-C NWs is fabricated. The as-prepared sensor showcases the good sensing performance for HQ and CC with comparative linearity ranges of 0.8-900 µM (HQ) and 0.6-800 µM (CC), low limits of detections (LODs) of 0.18 µM (S/N = 3) and 0.12 µM (S/N = 3) for HQ and CC, respectively. Notably, it also displays excellent practical application for the recognition of HQ and CC in the rain water, the tap water, the domestic wastewater and the lake water, which may be a promising candidate in environmental water monitoring and drinking water safety.

NiMnO3 Anchored on Reduced Graphene Oxide Nanosheets: A New High-Performance Microwave Absorbing Material.

With the increasing influence of electromagnetic radiation on precision instruments and organisms, there is an urgent need for research on lightweight and high-strength electromagnetic wave absorbing materials. This study has probed into a new composite absorbing material based on reduced graphene oxide (rGO)-NiMnO3, where the like-core-shell NiMnO3 is anchored on the rGO nanosheets to significantly improve the electromagnetic wave dissipation ability of the composite material using the inter-component dipole polarization and interface polarization. At the same time, NiMnO3 can effectively adjust the impedance matching ratio of rGO so that electromagnetic waves can effectively enter the absorbing material. At a thickness of 3.73 mm, the maximum absorption strength of rGO-NiMnO3 reaches -61.4 dB at 6.6 GHz; at a thickness of 2.5 mm, the adequate absorption bandwidth is 10.04-18.00 GHz, achieving a full coverage for the Ku band. As a new option for preparing lightweight and broadband electromagnetic wave absorbing materials, rGO-NiMnO3 is an ideal material for electromagnetic wave protection.

Pump-free microfluidic chip based laryngeal squamous cell carcinoma-related microRNAs detection through the combination of surface-enhanced Raman scattering techniques and catalytic hairpin assembly amplification.

MicroRNA (miRNA), as one of the ideal target biomarker analytes, plays an essential role in biological processes; thus, the development of rapidly sensitive detection methods is imperative. Herein, we proposed a pump-free surface-enhanced Raman scatting (SERS) microfluidic chip for the rapid and ultrasensitive detection of miR-106b and miR-196b, laryngeal squamous cell carcinoma (LSCC)-related miRNAs. Ag-Au core-shell nanorods (Ag-AuNRs) were applied to prepare SERS tags by modifying Raman reporters and hairpin DNAs. The capture probes were synthesized by labeling hairpin DNAs onto the magnetic beads (MBs) surface. In the presence of targets, the catalytic hairpin assembly (CHA) reactions between SERS tags and capture probes could be triggered, causing the aggregation of Ag-AuNRs. The tiny magnets installed under the rectangular chamber could magnetically gather the CHA products, leading to the further aggregation of Ag-AuNRs. Thus, this strategy could achieve the double aggregation of Ag-AuNRs, resulting in the significant amplification of the SERS signal. The proposed strategy achieved simultaneous and sensitive detection of miR-106b and miR-196b, with limits of detection low to aM level. The whole detection process could be completed within 5 min. Moreover, this microfluidic chip exhibited excellent reproducibility, stability, and specificity. The high accuracy of this SERS microfluidic chip was proved by practical analysis in LSCC patients' serum. The results demonstrated that SERS could be a promising alternative clinical diagnosis tool and exhibited potential application for the dynamic monitoring of cancer staging.

A dual-signal amplification strategy based on pump-free SERS microfluidic chip for rapid and ultrasensitive detection of non-small cell lung cancer-related circulating tumour DNA in mice serum.

Circulating tumour DNAs (ctDNAs) have been reported to be associated with real-time information of progression; however, an accurate and sensitive method has not been established. Herein, a novel dual-signal amplification strategy based on a pump-free surface-enhanced Raman scattering (SERS) microfluidic chip and a catalytic hairpin assembly (CHA) technique was developed for the dynamic monitoring of BRAF V600E and KRAS G12V, which are two non-small cell lung cancer (NSCLC)-related ctDNAs. In the presence of targets, CHA reactions can be triggered between two hairpin DNAs, fixing Pd-Au core-shell nanorods (Pd-AuNRs) onto the magnetic beads (MBs) surface. Thereafter, the composite structures can assemble under the action of magnet, enabling dual-amplification of SERS signal. Using this strategy, the limit of detection (LOD) was low (i.e. at the aM level) in serum. Furthermore, the entire chip-based analysis process could be completed within 5 min, eliminating manual incubation and heavy-duty injection pumps. The selectivity, reproducibility and uniformity of the proposed pump-free SERS microfluidic chip were satisfactory. This superior analysis strategy was finally applied to quantify BRAF V600E and KRAS G12V in tumour-bearing nude mice serum, the results of which corresponded with those of real-time polymerase chain reaction. Overall, this study provides a promising alternative tool for the dynamic monitoring of ctDNA expression level which can benefit the clinical diagnosis of NSCLC.

Tat-SynGAP improves angiogenesis and post-stroke recovery by inhibiting MST1/JNK signaling.

Small G protein Ras induces the activation of apoptosis-related molecule mammalian Ste20-like kinase1 (MST1)/JNK signal pathway, which is involved in the regulation of tissue damage under pathological conditions such as ischemic stroke. Our previous study indicated that GTPase-activating protein for Ras (SynGAP), a negative regulator of Ras, could bind with postsynaptic density protein-93 (PSD-93) and Tat-SynGAP (670-685aa) small peptide to exhibit neuroprotective role. Here, we report that Tat-SynGAP (670-685aa) reduced cerebral edema at acute cerebral ischemia/reperfusion (I/R), improved integrity of blood-brain barrier, and decreased cortical and striatum neuronal injury. Mechanistically, Tat-SynGAP (670-685aa) not only inhibited the phosphorylation of MST1 and JNK and the cleavage of caspase-3, but also facilitated the expression of angiogenesis related molecules VEGF and Ang-1. In conclusion, Tat-SynGAP (670-685aa) reduces neuronal apoptosis and cerebral infarction volume and maintains vascular stability and blood-brain barrier integrity by inhibiting MST1/JNK signaling pathway.

MAGT1 is required for HeLa cell proliferation through regulating p21 expression, S-phase progress, and ERK/p38 MAPK MYC axis.

Magnesium transporter subtype 1 (MAGT1) is known to participate in animal development and cell differentiation. Thus far, MAGT1 studies have mainly focused on its role in cardiomyocyte regulation and differentiation; only a few studies have demonstrated its role in cell proliferation. To investigate the underlying mechanism of MAGT1 in cell proliferation, HeLa and SiHa cells were transiently knocked down with different siRNAs. We showed that cell proliferation was substantially restricted by S-phase arrest and apoptosis in the MAGT1-knocked down cells, which was further confirmed by the increased expression of p21, cyclin-A1, and cyclin-B1, as well as the decreased expression of MYC, cyclin-D1, cyclin-E1, and CDK2. MAGT1 knockdown also resulted in significant changes in the transcriptional expression of 1,598 genes that were analyzed by RNA sequencing. Bioinformatics analysis showed that MAGT1 was related to the MAPK signaling pathway. Western blot analysis confirmed that the phosphorylation of extracellular signal-related protein kinase 1/2 (ERK1/2) and p38 was remarkably reduced in MAGT1 down-regulated groups. Additionally, MAGT1 was required for the function of viral proteins E6/E7 during cell proliferation and G1/S cell-cycle progression. Therefore, MAGT1 plays a crucial role in the proliferation of HPV-positive cervical cancer cells, S-phase progression, and the ERK/p38 MAPK signaling pathway. These results indicate the potential of MAGT1 as a novel target for anticancer research.Abbreviations: MAGT1: Magnesium transporter subtype 1; MAPK: Mitogen-activated protein kinase; XMEN: X-linked immunodeficiency with Magnesium defect, Epstein-Barr virus infection and Neoplasia; BMMSCs: Bone Marrow Mesenchymal Stem Cells; Dpp: Decapentaplegic; CDKIs: CDK inhibitors; GPCR: G-protein coupled receptor; GO: Gene Ontology; KEGG: Kyoto Encyclopedia of Genes and Genomes; RTK: Receptor Tyrosine Kinase; PTK: Protein Tyrosine Kinase; FGFR: Fibroblast Growth Factor Receptor; BMP: Bone Morphogenetic Protein; HPV18 E6/E7: Human Papillomavirus 18 Early protein 6/ early protein 7; FACS: Fluorescence Activated Cell Sorting; PI: Propidium Iodide.