Patulin, deoxynivalenol, zearalenone and T-2 toxin affect viability and modulate cytokine secretion in J774A.1 murine macrophages

Mycotoxins are secondary fungal metabolites, which occur in food and feed. They have detrimental effects on the health of humans and animals, and they are known to cause immunosuppression. In this study the effect of patulin, deoxynivalenol (DON), zearalenone (ZEN) and T-2 toxin exposure on the viability and the secretion of key pro- and anti-inflammatory cytokines from the murine macrophage cell line, J774A.1, was investigated. Exposure of macrophages to high doses of ZEN (100,000 pg/mL) and T-2 toxin (10,000 and 100,000 pg/mL) resulted in a significant decrease (P < 0.05 and P < 0.01) in cell viability. Exposure of macrophages to these mycotoxins resulted in a dose-dependent modulation of cytokine secretion. Specifically, exposure to low doses of patulin (0.001, 0.1 and 1 pg/mL) resulted in a statistically significant decrease in the secretion of the pro-inflammatory cytokines interleukin (IL) 6 (IL-6) and tumor necrosis factor alpha (TNF-α), following stimulation with lipopolysaccharide (LPS), a component of Gram-negative bacterial cell walls. Treatment with low doses of DON (0.001 pg/mL) and ZEN (0.001 and 0.01 pg/mL) significantly decreased (P < 0.01) the secretion of the pro-inflammatory cytokine IL-12p40, while several doses of T-2 toxin (0.001, 0.01, 0.1, 1 and 100 pg/mL) caused a significant decrease the expression of IL-6. Each of the mycotoxins also significantly increased the production of the anti-inflammatory cytokine IL-10, both before and after LPS stimulation. This data provides further insight into the mechanisms by which mycotoxins modulate the host immune response to exert their immunosuppressive activity

Design and fabrication of a low-cost wireless camera imaging system for centrifugal microfluidics

Centrifugal microfluidic devices offer a robust method for low-volume fluid handling by combining low-cost instrumentation with highly integrated automation. Crucial to the efficacy of Lab-on-a-Disc (LoaD) device operation is the selection of robust valving technology, the design of on-disc fluidic structures, and accurate control of disc spin-speeds (centrifugal force) during operation. The design and refinement of fluidic and valving structures is often guided by inspecting disc operation using high-speed camera systems. This approach involves synchronising image acquisition with disc rotation to visualise liquid flow through a series of images often presented in a video format. Depending on the decisions taken, such systems can cost from €4,000 upwards. This paper outlines the development of a low-cost centrifugal test-stand with an integrated imaging system using a generic wireless camera to record videos directly to a smartphone device. This imaging system can be fabricated using only 3D printers and a low-cost CNC milling machine from widely available materials for approximately €350. High-fidelity imaging of the entire disc for flow visualisation and the recording of real-time colour intensity measurements are facilitated by this standalone device. A vibration analysis study has been performed to determine the rotational velocity range at which the system can be safely operated. Furthermore, the efficacy of the imaging system has been demonstrated by performing real-time colour intensity measurements of dyed water dilution

Polyaniline nanofibres as templates for the covalent immobilisation of biomolecules

The attachment of antibodies onto polyaniline nanofibres using covalent chemistry was investigated for the first time. Polyaniline nanofibres were functionalised post-polymerisation to attach either amide or carboxylic acid side-groups. These templates could then be further modified to attach antibodies, specifically in this instance mouse immunoglobulin G (IgG). The resultant conjugates were characterised using a variety of techniques including infrared, UV–vis and Raman spectroscopy. Conjugates were then used to detect secondary antibodies (anti-IgG). Results from enzyme-linked immunoassay studies indi- cate successful binding of the antibody to the polyaniline nanofibres. Carboxyl functionalised polyaniline nanofibres are shown in particular to decrease non-specific binding in the immunoassay. Direct electri- cal communication between polyaniline nanofibres covalently linked to peroxidase-labelled antibodies was observed during cyclic voltammetry, which demonstrates their potential for further development as nano-dimensional immunosensors

Glycosylation in Indolent, Significant and Aggressive Prostate Cancer by Automated High-Throughput N-Glycan Profiling

The diagnosis and treatment of prostate cancer (PCa) is a major health-care concern worldwide. This cancer can manifest itself in many distinct forms and the transition from clinically indolent PCa to the more invasive aggressive form remains poorly understood. It is now universally accepted that glycan expression patterns change with the cellular modifications that accompany the onset of tumorigenesis. The aim of this study was to investigate if differential glycosylation patterns could distinguish between indolent, significant, and aggressive PCa. Whole serum N-glycan profiling was carried out on 117 prostate cancer patients’ serum using our automated, high-throughput analysis platform for glycan-profiling which utilizes ultra-performance liquid chromatography (UPLC) to obtain high resolution separation of N-linked glycans released from the serum glycoproteins. We observed increases in hybrid, oligomannose, and biantennary digalactosylated monosialylated glycans (M5A1G1S1, M8, and A2G2S1), bisecting glycans (A2B, A2(6)BG1) and monoantennary glycans (A1), and decreases in triantennary trigalactosylated trisialylated glycans with and without core fucose (A3G3S3 and FA3G3S3) with PCa progression from indolent through significant and aggressive disease. These changes give us an insight into the disease pathogenesis and identify potential biomarkers for monitoring the PCa progression, however these need further confirmation studies

Review: The increasing importance of carbon nanotubes and nanostructured conducting polymers in biosensors

The growing need for analytical devices requiring smaller sample volumes, decreased power consumption and improved performance have been driving forces behind the rapid growth in nanomaterials research. Due to their dimensions, nanostructured materials display unique properties not traditionally observed in bulk materials. Characteristics such as increased surface area along with enhanced electrical/optical properties make them suitable for numerous applications such as nanoelectronics, photovoltaics and chemical/biological sensing. In this review we examine the potential that exists to use nanostructured materials for biosensor devices. By incorporating nanomaterials, it is possible to achieve enhanced sensitivity, improved response time and smaller size. Here we report some of the success that has been achieved in this area. Many nanoparticle and nanofibre geometries are particularly relevant, but in this paper we specifically focus on organic nanostructures, reviewing conducting polymer nanostructures and carbon nanotubes

Antibody-Based Sensors: Principles, Problems and Potential for Detection of Pathogens and Associated Toxins

Antibody-based sensors permit the rapid and sensitive analysis of a range of pathogens and associated toxins. A critical assessment of the implementation of such formats is provided, with reference to their principles, problems and potential for ‘on-site’ analysis. Particular emphasis is placed on the detection of foodborne bacterial pathogens, such as Escherichia coli and Listeria monocytogenes, and additional examples relating to the monitoring of fungal pathogens, viruses, mycotoxins, marine toxins and parasites are also provided

Point-of-Care Compatibility of Ultra-Sensitive Detection Techniques for the Cardiac Biomarker Troponin I—Challenges and Potential Value

Cardiac biomarkers are frequently measured to provide guidance on the well-being of a patient in relation to cardiac health with many assays having been developed and widely utilised in clinical assessment. Effectively treating and managing cardiovascular disease (CVD) relies on swiftly responding to signs of cardiac symptoms, thus providing a basis for enhanced patient management and an overall better health outcome. Ultra-sensitive cardiac biomarker detection techniques play a pivotal role in improving the diagnostic capacity of an assay and thus enabling a better-informed decision. However, currently, the typical approach taken within healthcare depends on centralised laboratories performing analysis of cardiac biomarkers, thus restricting the roll-out of rapid diagnostics. Point-of-care testing (POCT) involves conducting the diagnostic test in the presence of the patient, with a short turnaround time, requiring small sample volumes without compromising the sensitivity of the assay. This technology is ideal for combatting CVD, thus the formulation of ultra-sensitive assays and the design of biosensors will be critically evaluated, focusing on the feasibility of these techniques for point-of-care (POC) integration. Moreover, there are several key factors, which in combination, contribute to the development of ultra-sensitive techniques, namely the incorporation of nanomaterials for sensitivity enhancement and manipulation of labelling methods. This review will explore the latest developments in cardiac biomarker detection, primarily focusing on the detection of cardiac troponin I (cTnI). Highly sensitive detection of cTnI is of paramount importance regarding the rapid rule-in/rule-out of acute myocardial infarction (AMI). Thus the challenges encountered during cTnI measurements are outlined in detail to assist in demonstrating the drawbacks of current commercial assays and the obstructions to standardisation. Furthermore, the added benefits of introducing multi-biomarker panels are reviewed, several key biomarkers are evaluated and the analytical benefits provided by multimarkers-based methods are highlighted