A double boronic acid affinity "sandwich" SERS biosensor based on magnetic boronic acid controllable-oriented imprinting for high-affinity biomimetic specific recognition and rapid detection of target glycoproteins.

Transferrin (TRF), recognized as a glycoprotein clinical biomarker and therapeutic target, has its concentration applicable for disease diagnosis and treatment monitoring. Consequently, this study developed boronic acid affinity magnetic surface molecularly imprinted polymers (B-MMIPs) with pH-responsitivity as the "capture probe" for TRF, which have high affinity similar to antibodies, with a dissociation constant of (3.82 ± 0.24) × 10-8 M, showing 7 times of reusability. The self-copolymerized imprinted layer synthesized with dopamine (DA) and 3-Aminophenylboronic acid (APBA) as double monomers avoided nonspecific binding sites and produced excellent adsorption properties. Taking the gold nanostar (AuNS) with a branch tip "hot spot" structure as the core, the silver-coated AuNS functionalized with the biorecognition element 4-mercaptophenylboronic acid (MPBA) was employed as a surface-enhanced Raman scattering (SERS) nanotag (AuNS@Ag-MPBA) to label TRF, thereby constructing a double boronic acid affinity "sandwich" SERS biosensor (B-MMIPs-TRF-SERS nanotag) for the highly sensitive detection of TRF. The SERS biosensor exhibited a detection limit for TRF of 0.004 ng/mL, and its application to spiked serum samples confirmed its reliability and feasibility, demonstrating significant potential for clinical TRF detection. Moreover, the SERS biosensor designed in this study offers advantages in stability, detection speed (40 min), and cost efficiency. The portable Raman instrument for SERS detection fulfills the requirements for point-of-care testing.

APC/C-regulated CPT1C promotes tumor progression by upregulating the energy supply and accelerating the G1/S transition.

BACKGROUND: In addition to functioning as a precise monitoring mechanism in cell cycle, the anaphase-promoting complex/cyclosome (APC/C) is reported to be involved in regulating multiple metabolic processes by facilitating the ubiquitin-mediated degradation of key enzymes. Fatty acid oxidation is a metabolic pathway utilized by tumor cells that is crucial for malignant progression; however, its association with APC/C remains to be explored. METHODS: Cell cycle synchronization, immunoblotting, and propidium iodide staining were performed to investigate the carnitine palmitoyltransferase 1 C (CPT1C) expression manner. Proximity ligation assay and co-immunoprecipitation were performed to detect interactions between CPT1C and APC/C. Flow cytometry, 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2 H-tetrazolium, inner salt (MTS) assays, cell-scratch assays, and transwell assays and xenograft transplantation assays were performed to investigate the role of CPT1C in tumor progression in vitro and in vivo. Immunohistochemistry was performed on tumor tissue microarray to evaluate the expression levels of CPT1C and explore its potential clinical value. RESULTS: We identified CPT1C as a novel APC/C substrate. CPT1C protein levels exhibited cell cycle-dependent fluctuations, peaking at the G1/S boundary. Elevated CPT1C accelerated the G1/S transition, facilitating tumor cell proliferation in vitro and in vivo. Furthermore, CPT1C enhanced fatty acid utilization, upregulated ATP levels, and decreased reactive oxygen species levels, thereby favoring cell survival in a harsh metabolic environment. Clinically, high CPT1C expression correlated with poor survival in patients with esophageal squamous cell carcinoma. CONCLUSIONS: Overall, our results revealed a novel interplay between fatty acid utilization and cell cycle machinery in tumor cells. Additionally, CPT1C promoted tumor cell proliferation and survival by augmenting cellular ATP levels and preserving redox homeostasis, particularly under metabolic stress. Therefore, CPT1C could be an independent prognostic indicator in esophageal squamous cell carcinoma.

FPBA-modified magnetic nanoparticles combined with Au@AgNPs for label-free SERS detection of foodborne pathogens in milk.

We report a low-cost and highly sensitive label-free SERS biosensor for pathogen detection. Herein, this study prepared 4-formylphenylboric acid (FPBA) functionalized magnetic nanoparticles to adsorb pathogenic bacteria through boric acid affinity principle, and used aptamer modified Au@AgNPs as SERS substrate to specifically combine with pathogenic bacteria to form a sandwich structure. The pathogenic bacteria were detected by portable Raman spectrometer for SERS detection, and the fingerprint signals of pathogenic bacteria were analyzed by principal component analysis (PCA) to achieve the purpose of classification and identification of pathogenic bacteria. Under the optimized conditions, the SERS detection of Staphylococcus aureus (S. aureus) was 102 âˆ¼ 106 CFU/mL (R2 = 0.9925), and the limit of detection (LOD) was 34 CFU/mL. The linear range of Escherichia coli (E. coli) showed a good linear relationship in the range of 102 âˆ¼ 106 CFU/mL (R2 = 0.9993), and the LOD was 18 CFU/mL. The whole detection process was used the portable Raman spectrometer, which makes it suitable for the application of point-of-care testing (POCT).

Combining multisite functionalized magnetic nanomaterials with interference-free SERS nanotags for multi-target sepsis biomarker detection.

Surface-enhanced Raman scattering (SERS) is an ultra-sensitive vibration spectroscopy technology, with the advantages of multi-index and non-destructive quantitative detection, has attracted much attention in the joint detection of biomarkers. A novel SERS biosensor with multisite capture and interference-free quantification was designed for the joint detection of the sepsis biomarker interleukin-6 (IL-6) and procalcitonin (PCT). This biosensor had two interference-free core-shell SERS probes with highly efficient electromagnetic enhancement and a multisite functionalized magnetic nanomaterial with high adsorption capacity. They formed sandwich structure with the targets through boronic affinity and immunoreaction, and the multi-target quantitative analysis of biomarkers in serum was performed using a portable Raman spectrometer in the Raman-silent region. The SERS biosensor was exhibited highly sensitive with detection limits of 0.584 and 2.99 pg/mL for IL-6 and PCT, respectively. In addition, it exhibited excellent selectivity and specificity even with the interference of other proteins. As this SERS method showed excellent performance in the detection of sepsis, it has great potential for multi-index detection in clinical diagnosis of major diseases.

High-sensitivity biosensor based on SERS integrated with dendrimer-assisted boronic acid-functionalized magnetic nanoparticles for IL-6 detection in human serum.

High-sensitivity quantitative analysis of sepsis disease markers in circulating blood is essential for sepsis early diagnosis, rapid stratification, and interventional treatment. Herein, a high-sensitivity biosensor combining surface-enhanced Raman spectroscopy (SERS) and functionalized magnetic materials was developed to quantitatively detect interleukin-6 (IL-6), a glycoprotein disease marker closely related to sepsis. First, boronic acid-functionalized magnetic nanomaterials with high adsorption performance were synthesized by utilizing the branched polyethyleneimine to provide many binding sites for boronic acid. Under antibody-free conditions, dendrimer-assisted boronic acid-functionalized magnetic nanomaterials selectively capture glycoproteins in complex biological samples as bio-capture element. Then, a core-shell bimetallic material with plenty of 'hot spots' was designed and synthesized as the enhancement substrate. The 4-Mercaptobenzonitrile (4-MP) with a characteristic peak at 2224 cm-1(Raman-silent region) was embedded as the Raman reporter to form a SERS immune probe with highly efficient electromagnetic enhancement effect, achieving specific recognition and high-sensitivity detection of IL-6 on bio-capture elements. Using this strategy for quantitative analysis of IL-6, a wide detection range (0.5-5000 pg ml-1) and a low detection limit (0.453 pg ml-1) were obtained. Moreover, this method exhibited excellent detection performance for IL-6 in human serum samples, demonstrating its potential promise in screening clinically relevant diseases. The biosensor presented here not only provides a novel and universally applicable sensing strategy for the enrichment and detection of trace glycoprotein disease markers, but also the application of a portable Raman spectrometer provides a more reliable experimental basis for the diagnosis and treatment of major diseases in the clinic or remote and deprived areas.

Integration of three non-interfering SERS probes combined with ConA-functionalized magnetic nanoparticles for extraction and detection of multiple foodborne pathogens.

A sandwich-structured SERS biosensor has been constructed for simultaneous detection of multiple pathogenic bacteria, consisting of non-interfering SERS probes for bacterial labeling and ConA-functionalizd magnetic nanoparticles for bacteria extraction. A the preparation method of PP3 SERS probe with high Raman activity is reported for the first time. Since the PP3 SERS probe has a very strong Raman peak at 2081 cm-1 in the "Raman silent region," the mixed SERS probe formed with MP1 and DP2 can meet the needs of multiple foodborne pathogen detection. Significantly, S. aureus, E. coli, and P. aeruginosa can be successfully extracted upon external magnetic field, and the limit of detection (LOD) is 1 CFU‧mL-1, lower than that of the congeneric detectors. This work paves a new way for the construction of a novel detector and absorbent for different bacteria in complex samples by using SERS probe.

Myopic Shift in a Patient with Dengue Fever.

PURPOSE: This report aims to present a case of dengue-related myopic shift. METHODS: This is a case report of a patient with dengue-related transient myopia, and demonstrates possible underlying pathophysiology. RESULTS: A 38-year-old gentleman presented with bilateral blurring of vision with an unaided visual acuity (VA) of 6/120 bilaterally. He had a refractive error of -2.50 dioptres in the right eye, and -3.50 dioptres in the left eye. Ultrasound biomicroscopy (UBM) revealed suprachoroidal effusion with anterior displacement of the lens-iris complex bilaterally. Biometry performed showed lens thickness (LT) of 4.47 mm in the right eye, and 4.65 mm in the left eye. His unaided VA was noted to be 6/6 bilaterally 4 days later. CONCLUSIONS: Dengue-related myopic shift was likely secondary to two mechanisms. Firstly, suprachoroidal effusion resulted in an anterior displacement of the lens-iris complex. Secondly, there was an increase in the antero-posterior diameter of the lens, resulting in index myopia.

Relationships between the Mini-InDel Variants within the Goat CFAP43 Gene and Body Traits.

The cilia- and flagella-associated protein 43 (CFAP43) gene encodes a member of the cilia- and flagellum-associated protein family. Cilia on the cell surface influence intercellular signaling and are involved in biological processes such as osteogenesis and energy metabolism in animals. Previous studies have shown that insertion/deletion (InDel) variants in the CFAP43 gene affect litter size in Shaanbei white cashmere (SBWC) goats, and that litter size and body traits are correlated in this breed. Therefore, we hypothesized that there is a significant relationship between InDel variants within the CFAP43 gene and body traits in SBWC goats. Herein, we first investigated the association between three InDel variant loci (L-13, L-16, and L-19 loci) within CFAP43 and body traits in SBWC goats (n = 1827). Analyses revealed that the L-13, L-16, and L-19 loci were significantly associated with chest depth, four body traits, and three body traits, respectively. The results of this study are in good agreement with those previously reported and could provide useful molecular markers for the selection and breeding of goats for body traits.

Detection of genetic variation in bovine CRY1 gene and its associations with carcass traits.

The biological clock (also known as circadian clock) is closely related to growth and development, metabolism, and diseases in animals. As a part of the circadian clock, the cryptochrome circadian regulator 1 (CRY1) gene is involved in the regulation of biological processes such as osteogenesis, energy metabolism and cell proliferation, however, few studies have been reported on the relationship between this gene and animal carcass traits. Herein, a total of four insertion/deletion (InDel) loci within the CRY1 gene were detected in Shandong Black Cattle Genetic Resource (SDBCGR) population (n = 433). Among them, the P1-6-bp-del locus was polymorphic in population of interest. Moreover, the P1-6-bp-del locus showed two genotypes, with a higher insertion/insertion (II) genotype frequency (0.751) than insertion/deletion (ID) genotype frequency (0.249). Correlation analysis showed that the P1-6-bp-del locus polymorphisms were significantly associated with twenty carcass traits (e.g., slaughter weight, limb weight, and belly meat weight). Individuals with II genotype were significantly better than those with ID genotype for eighteen carcass traits. Therefore, the P1-6-bp-del locus of the CRY1 gene can be used as a molecular marker for beef cattle breeding.

Branch retinal artery occlusion in a young patient after radiotherapy for nasopharyngeal carcinoma.

PURPOSE: To report a case of branch retinal artery occlusion (BRAO) in a young patient who received previous neck radiotherapy for nasopharyngeal carcinoma. METHODS: We describe an interesting case of a branch retinal artery occlusion in a patient with previous neck radiotherapy for nasopharyngeal carcinoma 14 years ago. PATIENT: The patient was a 49 year old male, who presented to the retina service in Tan Tock Seng Hospital. RESULTS: Ultrasound of the carotid arteries revealed more than 50% bilateral common carotid arteries stenosis, and 80-99% bilateral internal carotid artery (ICA) stenosis. Magnetic resonance imaging of the brain showed presence of chronic infarcts. Screening for hypercoaguable states and cardioembolic causes were unremarkable. CONCLUSION: Head and neck irradiation is a significant risk factor for developing carotid stenosis and its consequent complications such as retinal artery occlusions and cerebrovascular events.

Application progress of magnetic molecularly imprinted polymers chemical sensors in the detection of biomarkers.

Specific recognition and highly sensitive detection of biomarkers play an essential role in identification, early diagnosis and prevention of many diseases. Magnetic molecularly imprinted polymers (MMIPs) have been widely used to capture biomimetic receptors for targets in various complex matrices due to their superior recognition ability, structural stability, and rapid separation characteristics, which overcome the existing deficiencies of traditional recognition elements such as antibodies, aptamers. The integration of MMIPs as recognition elements with chemical sensors opens new opportunities for the development of advanced analytical devices with improved selectivity and sensitivity, shorter analysis time, and lower cost. Recently, MMIPs-chemical sensors (MMIPs-CS) have made significant progress in detection, but many challenges and development spaces remain. Therefore, this review focuses on the research progress of the sensor based on biomarker detection and introduces the surface modification of the magnetic support material used to prepare high selective MMIPs, as well as the selective extraction of target biomarkers by MMIPs from the complex biological sample matrix. Based on the understanding of optical sensors and electrochemical sensors, the applications of MMIPs-optical sensors (MMIPs-OS) and MMIPs-electrochemical sensors (MMIPs-ECS) for biomarker detection were reviewed and discussed in detail. Moreover, it provides an overview of the challenges in this research area and the potential strategies for the rational design of high-performance MMIPs-CS, accelerating the development of multifunctional MMIPs-CS.

Recent advancements in microfluidic chip biosensor detection of foodborne pathogenic bacteria: a review.

Foodborne diseases caused by pathogenic bacteria pose a serious threat to human health. Early and rapid detection of foodborne pathogens is an urgent task for preventing disease outbreaks. Microfluidic devices are simple, automatic, and portable miniaturized systems. Compared with traditional techniques, microfluidic devices have attracted much attention because of their high efficiency and convenience in the concentration and detection of foodborne pathogens. This article firstly reviews the bio-recognition elements integrated on microfluidic chips in recent years and the progress of microfluidic chip development for pathogen pretreatment. Furthermore, the research progress of microfluidic technology based on optical and electrochemical sensors for the detection of foodborne pathogenic bacteria is summarized and discussed. Finally, the future prospects for the application and challenges of microfluidic chips based on biosensors are presented.

SERS-based boronate affinity biosensor with biomimetic specificity and versatility: Surface-imprinted magnetic polymers as recognition elements to detect glycoproteins.

Glycoproteins are a class of proteins with significant biological functions and clinical implications. Due to glycoproteins' reliability for the quantitative analysis, they have been used as biomarkers and therapeutic targets for disease diagnosis. We propose a sandwich structure-based boronate affinity biosensor that can separate and detect target glycoproteins by magnetic separation and Surface-enhanced Raman scattering (SERS) probes. The biosensor relies on boronic acid affinity magnetic molecularly imprinted polymer (MMIPs) with pH response as "capturing probe" for glycoproteins, and Au-MPBA@Ag modified with 4-mercaptophenylboronic acid (MPBA) as SERS probes, among which, MPBA has both strong SERS activity and can specifically recognize and bind to glycoproteins. MMIPs ensured specific and rapid analysis, and SERS detection provided high sensitivity. The proposed boronate affinity SERS strategy exhibited universal applicability and provided high sensitivity with limit of detection of 0.053 ng/mL and 0.078 ng/mL for horseradish peroxidase and acid phosphatase, respectively. Ultimately, the boronate affinity SERS strategy was successfully applied in detection of glycoprotein in spiked serum sample with recovery between 90.6% and 103.4%, respectively. In addition, this study used a portable Raman meter, which can meet the requirements of point-of-care testing. The biosensor presented here also has advantages in terms of cost-effectiveness, stability, and detection speed.

In Silico Structure-Based Design of Antiviral Peptides Targeting the Severe Fever with Thrombocytopenia Syndrome Virus Glycoprotein Gn.

Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging tick-borne bunyavirus in Asia that causes severe disease. Despite its clinical importance, treatment options for SFTSV infection remains limited. The SFTSV glycoprotein Gn plays a major role in mediating virus entry into host cells and is therefore a potential antiviral target. In this study, we employed an in silico structure-based strategy to design novel cyclic antiviral peptides that target the SFTSV glycoprotein Gn. Among the cyclic peptides, HKU-P1 potently neutralizes the SFTSV virion. Combinatorial treatment with HKU-P1 and the broad-spectrum viral RNA-dependent RNA polymerase inhibitor favipiravir exhibited synergistic antiviral effects in vitro. The in silico peptide design platform in this study may facilitate the generation of novel antiviral peptides for other emerging viruses.

Application of lectin-based biosensor technology in the detection of foodborne pathogenic bacteria: a review.

Foodborne diseases caused by pathogenic bacteria pose a serious threat to human health. Early and rapid detection of foodborne pathogens is urgently needed. The use of biosensors to identify and detect pathogenic bacteria has attracted ample attention because of their high sensitivity, near real-time quantification without enrichment, on-site detection, simple operation, and so on. As a promising alternative recognition element in biosensors, lectins have been widely studied in bacterial detection because of their high stability and low cost. In this review, we highlight the progress of lectin-based pathogen detection methods, including various electrochemical methods, optical methods and quartz crystal microbalance methods, as well as lectin based microfluidic methods. The interaction mechanism between lectins and bacterial recognition site-sugars is also studied. Finally, the future prospects and challenges in the development of lectin-based biosensors are discussed.

SERS-based magnetic immunoassay for simultaneous detection of cTnI and H-FABP using core-shell nanotags.

Acute myocardial infarction (AMI) is the single leading cause of worldwide mortality and morbidity. Heart-type fatty acid-binding protein (H-FABP) and cardiac troponin I (cTnI), as biomarkers emerging at different stages of AMI, have complementary advantages in terms of specificity and sensitivity. Therefore, we developed a magnetic immunoassay method based on surface-enhanced Raman scattering (SERS) to detect H-FABP and cTnI simultaneously. Herein, two mutually independent Raman reporter molecules were embedded between a gold core and silver shell and then combined with a tracer antibody to form a SERS immunoprobe. During detection, the SERS immunoprobe, target antigen and capture probe undergo an immune reaction to form a sandwich structure, and then the immune complex was enriched by a specific reaction of streptavidin on the surface of magnetic beads with biotin. Finally, the concentration of biomarkers was quantified by detecting the characteristic Raman peak intensities of the two Raman reporter molecules. Under the optimized conditions, the minimum detection limits of H-FABP and cTnI were 0.6396 and 0.0044 ng mL-1, respectively. Besides, the target antigen does not cross-react with non-specific proteins, showing good specificity. Therefore, our proposed SERS-based magnetic immunoassay method has the advantages of accuracy, rapidity and good selectivity, and has great potential for early diagnosis of acute myocardial infarction disease.

[Research progress on the expression and function of erythropoietin-producing hepatomocellular receptors and their receptor-interacting proteins in oral-related diseases].

Erythropoietin-producing hepatomocellular receptors and their receptor-interacting proteins (Eph/ephrin) can participate in the regulation of growth and development and promote the development of diseases through short-distance signal transduction between cells. To study the mechanism of Eph/ephrin and oral-related diseases, we provided a new theoretical basis and a strategy for the treatment of oral diseases. The Eph/ephrin pathway has been used to regulate oral diseases, especially in periodontal disease prevention, orthodontic bone reconstruction, and biological treatment of oral tumors. This paper reviews the research progress of Eph/ephrin pathway in oral-related diseases.

Toxicity Assessment of 4 Azo Dyes in Zebrafish Embryos.

Azo dyes are used widely as color additives in food, drugs, and cosmetics; hence, there is an increasing concern about their safety and possible health hazards. In the present study, we chose 4 azo dyes tartrazine, Sunset Yellow, amaranth, and Allura red and evaluated their developmental toxicity on zebrafish embryos. At concentration levels of 5 to 50 mM, we found that azo dyes can induce hatching difficulty and developmental abnormalities such as cardiac edema, decreased heart rate, yolk sac edema, and spinal defects including spinal curvature and tail distortion. Exposure to 100 mM of each azo dye was completely embryolethal. The median lethal concentration (LC50), median effective concentration (EC50), and teratogenic index (TI) were calculated for each azo dye at 72 hours postfertilization. For tartrazine, the LC50 was 47.10 mM and EC50 value was at 42.66 mM with TI ratio of 1.10. For Sunset Yellow, the LC50 was 38.93 mM and EC50 value was at 29.81 mM with TI ratio of 1.31. For amaranth, the LC50 was 39.86 mM and EC50 value was at 31.94 mM with TI ratio of 1.25. For Allura red, the LC50 was 47.42 mM and EC50 value was 40.05 mM with TI ratio of 1.18. This study reports the developmental toxicity of azo dyes in zebrafish embryos at concentrations higher than the expected human exposures from consuming food and drugs containing azo dyes.

A novel surface-enhanced Raman scattering method for simultaneous detection of ketamine and amphetamine.

As common psychotropic drugs, ketamine (KET) and amphetamine (AMP) are often consumed by drug users at the same time, which seriously threatens people's health. Therefore, the study of simultaneous detection methods for KET and AMP is imperative. In this study, a novel method for the simultaneous detection of KET and AMP in serum was established on the basis of surface-enhanced Raman scattering (SERS). The antibodies were attached on Au@Ag core-shell nanoparticles embedded with different Raman reporters as the detection substrates. The labelled antigens KET-BSA and AMP-BSA were linked to carboxyl magnetic beads, and by adopting the principle of competitive immunoassay, the quantitative detections of ketamine and amphetamine were realized at the same time by detecting the Raman signals at different characteristic peaks on the magnetic beads. A good correlation was shown between ketamine and amphetamine and Raman signal response values were in the concentration range of 0-60 ng mL-1 and 0-200 ng mL-1, and the limits of detection were 1.64 and 2.44 ng mL-1. This method had the advantages of simple, rapid operation, and high sensitivity, and can realise double indicator simultaneous detection, which provided a more favorable scientific basis for preventing or reducing drug abuse, and identifying and monitoring drug users.