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The Analyst Jan 2015Carbohydrate molecules are involved in many of the cellular processes that are important for life. By combining the specific analyte targeting of carbohydrates with the... (Review)
Review
Carbohydrate molecules are involved in many of the cellular processes that are important for life. By combining the specific analyte targeting of carbohydrates with the multivalent structure and change of solution colour as a consequence of plasmonic interactions with the aggregation of metal nanoparticles, glyconanoparticles have been used extensively for the development of bioanalytical assays. The noble metals used to create the nanocore, the methodologies used to assemble the carbohydrates on the nanoparticle surface, the carbohydrate chosen for each specific target, the length of the tether that separates the carbohydrate from the nanocore and the density of carbohydrates on the surface all impact on the structural formation of metal based glyconanoparticles. This tutorial review highlights these key components, which directly impact on the selectivity and sensitivity of the developed bioassay, for the colorimetric detection of lectins, toxins and viruses.
Topics: Biological Assay; Carbohydrates; Colorimetry; Nanoparticles
PubMed: 25277069
DOI: 10.1039/c4an01466a -
Plant & Cell Physiology Nov 2021Many plant processes occur in the context of and in interaction with a surrounding matrix such as soil (e.g. root growth and root-microbe interactions) or surrounding... (Review)
Review
Many plant processes occur in the context of and in interaction with a surrounding matrix such as soil (e.g. root growth and root-microbe interactions) or surrounding tissues (e.g. pollen tube growth through the pistil), making it difficult to study them with high-resolution optical microscopy. Over the past decade, microfabrication techniques have been developed to produce experimental systems that allow researchers to examine cell behavior in microstructured environments that mimic geometrical, physical and/or chemical aspects of the natural growth matrices and that cannot be generated using traditional agar plate assays. These microfabricated environments offer considerable design flexibility as well as the transparency required for high-resolution, light-based microscopy. In addition, microfluidic platforms have been used for various types of bioassays, including cellular force assays, chemoattraction assays and electrotropism assays. Here, we review the recent use of microfluidic devices to study plant cells and organs, including plant roots, root hairs, moss protonemata and pollen tubes. The increasing adoption of microfabrication techniques by the plant science community may transform our approaches to investigating how individual plant cells sense and respond to changes in the physical and chemical environment.
Topics: Biological Assay; Bryophyta; Imaging, Three-Dimensional; Microfluidic Analytical Techniques; Plant Cells; Plant Roots; Pollen Tube; Protoplasts
PubMed: 34027549
DOI: 10.1093/pcp/pcab067 -
Molecular and Biochemical Parasitology Nov 2022Caenorhabditis elegans is a uniquely powerful tool to aid understanding of fundamental nematode biology. While C. elegans boasts an unrivalled array of functional... (Review)
Review
Caenorhabditis elegans is a uniquely powerful tool to aid understanding of fundamental nematode biology. While C. elegans boasts an unrivalled array of functional genomics tools and phenotype bioassays the inherent differences between free-living and parasitic nematodes underscores the need to develop these approaches in tractable parasite models. Advances in functional genomics approaches, including RNA interference and CRISPR/Cas9 gene editing, in the parasitic nematodes Strongyloides ratti and Strongyloides stercoralis provide a unique and timely opportunity to probe basic parasite biology and reveal novel anthelmintic targets in species that are both experimentally and therapeutically relevant pathogens. While Strongyloides functional genomics tools have progressed rapidly, the complementary range of bioassays required to elucidate phenotypic outcomes post-functional genomics remain more limited in scope. To adequately support the exploitation of functional genomic pipelines for studies of gene function in Strongyloides a comprehensive set of species- and parasite-specific quantitative bioassays are required to assess nematode behaviours post-genetic manipulation. Here we review the scope of the current Strongyloides bioassay toolbox, how established Strongyloides bioassays have advanced knowledge of parasite biology, opportunities for Strongyloides bioassay development and, the need for investment in tractable model parasite platforms such as Strongyloides to drive the discovery of novel targets for parasite control.
Topics: Animals; Parasites; Caenorhabditis elegans; Nematoda; Genomics; Strongyloides stercoralis; Biological Assay
PubMed: 36240960
DOI: 10.1016/j.molbiopara.2022.111526 -
SLAS Discovery : Advancing Life... Dec 2021
Topics: Biological Assay; Drug Discovery; Humans
PubMed: 34813395
DOI: 10.1177/24725552211054044 -
Peptides Jul 2021Gastrointestinal hormones are peptides, and the gastrointestinal tract is the largest endocrine organ in the body for production of peptide hormones. As a premise for... (Review)
Review
Gastrointestinal hormones are peptides, and the gastrointestinal tract is the largest endocrine organ in the body for production of peptide hormones. As a premise for accurate measurement of gastrointestinal hormones, the present review provides first an overview over the complex biology of the hormones: The structures and structural homologies; biogenetic aspects; phenotype variabilities; and cellular expression in- and outside the digestive tract. Second, the different methodological principles for measurement are discussed: Bioassay, radioimmunoassay (RIA), enzyme-linked immunosorbent assay (ELISA), mass-spectrometry (LC-MS/MS) and processing-independent analysis (PIA). Third, the variability of secretion patterns for some of the gut hormones is illustrated. Finally, the diagnostic value of gut hormone measurement is discussed. The review concludes that measurement of gastrointestinal peptide hormones is relevant not only for examination of digestive functions and diseases, but also for extra-intestinal functions. Moreover, it concludes that, so far, immunoassay technologies (RIA and ELISA) in modernized forms are still the most feasible for accurate measurements of gastrointestinal hormones in biological fluids. Mass-spectrometry technologies are promising, but still too insensitive and expensive.
Topics: Alternative Splicing; Animals; Biological Assay; Blood Chemical Analysis; Enzyme-Linked Immunosorbent Assay; Gastrointestinal Hormones; Gene Expression; Humans; Mass Spectrometry; Peptide Hormones; Radioimmunoassay
PubMed: 33811948
DOI: 10.1016/j.peptides.2021.170545 -
Molecules (Basel, Switzerland) Jan 2020Oxylipins are derivatives of polyunsaturated fatty acids and due to their important and diverse functions in the body, they have become a popular subject of studies. The... (Review)
Review
Oxylipins are derivatives of polyunsaturated fatty acids and due to their important and diverse functions in the body, they have become a popular subject of studies. The main challenge for researchers is their low stability and often very low concentration in samples. Therefore, in recent years there have been developments in the extraction and analysis methods of oxylipins. New approaches in extraction methods were described in our previous review. In turn, the old analysis methods have been replaced by new approaches based on mass spectrometry (MS) coupled with liquid chromatography (LC) and gas chromatography (GC), and the best of these methods allow hundreds of oxylipins to be quantitatively identified. This review presents comparative and comprehensive information on the progress of various methods used by various authors to achieve the best results in the analysis of oxylipins in biological samples.
Topics: Animals; Biological Assay; Humans; Oxylipins
PubMed: 31952163
DOI: 10.3390/molecules25020349 -
Regulatory Toxicology and Pharmacology... Oct 2021Historical control data (HCD) consist of pooled control group responses from bioassays. These data must be collected and are often used or reported in regulatory... (Review)
Review
Historical control data (HCD) consist of pooled control group responses from bioassays. These data must be collected and are often used or reported in regulatory toxicology studies for multiple purposes: as quality assurance for the test system, to help identify toxicological effects and their effect-size relevance and to address the statistical multiple comparison problem. The current manuscript reviews the various classical and potential new approaches for using HCD. Issues in current practice are identified and recommendations for improved use and discussion are provided. Furthermore, stakeholders are invited to discuss whether it is necessary to consider uncertainty when using HCD formally and statistically in toxicological discussions and whether binary inclusion/exclusion criteria for HCD should be revised to a tiered information contribution to assessments. Overall, the critical value of HCD in toxicological bioassays is highlighted when used in a weight-of-evidence assessment.
Topics: Biological Assay; Databases, Factual; Dose-Response Relationship, Drug; Risk Assessment; Toxicology
PubMed: 34364928
DOI: 10.1016/j.yrtph.2021.105024 -
Parasites & Vectors Dec 2022Insecticide resistance remains a major public health problem. Resistance surveillance is critical for effective vector control and resistance management planning....
BACKGROUND
Insecticide resistance remains a major public health problem. Resistance surveillance is critical for effective vector control and resistance management planning. Commonly used insecticide susceptibility bioassays for mosquitoes are the CDC bottle bioassay and the WHO tube test. Less commonly used in the field but considered the gold standard for assessing insecticide susceptibility in the development of novel insecticides is the topical application bioassay. Each of these bioassays has critical differences in how they assess insecticide susceptibility that impacts their ability to differentiate between resistant and susceptible populations or determine different levels of resistance intensity.
METHODS
We compared the CDC bottle bioassay, the WHO tube test, and the topical application bioassay in establishing the dose-response against deltamethrin (DM) using the DM-resistant Aedes aegypti strain MC1. Mosquitoes were exposed to a range of insecticide concentrations to establish a dose-response curve and assess variation around model predictions. In addition, 10 replicates of 20-25 mosquitoes were exposed to a fixed dose with intermediate mortality to assess the degree of variation in mortality.
RESULTS
The topical application bioassay exhibited the lowest amount of variation in the dose-response data, followed by the WHO tube test. The CDC bottle bioassay had the highest level of variation. In the fixed-dose experiment, a higher variance was similarly found for the CDC bottle bioassay compared with the WHO tube test and topical application bioassay.
CONCLUSION
These data suggest that the CDC bottle bioassay has the lowest power and the topical application bioassay the highest power to differentiate between resistant and susceptible populations and assess changes over time and between populations. This observation has significant implications for the interpretation of surveillance results from different assays. Ultimately, it will be important to discuss optimal insecticide resistance surveillance tools in terms of the surveillance objective, practicality in the field, and accuracy of the tool to reach that objective.
Topics: Animals; United States; Insecticides; Aedes; Mosquito Vectors; Insecticide Resistance; Biological Assay; Centers for Disease Control and Prevention, U.S.; World Health Organization; Pyrethrins
PubMed: 36539831
DOI: 10.1186/s13071-022-05583-2 -
PloS One 2021Varroa destructor Anderson and Trueman, is an ectoparasitic mite of honey bees, Apis mellifera L., that has been considered a major cause of colony losses. Synthetic...
Varroa destructor Anderson and Trueman, is an ectoparasitic mite of honey bees, Apis mellifera L., that has been considered a major cause of colony losses. Synthetic miticides have been developed and registered to manage this ectoparasite, however, resistance to registered pyrethroid and organophosphate Varroacides have already been reported in Canada. To test toxicity of miticides, current contact-based bioassay methods are designed to evaluate mites and bees separately, however, these methods are unlikely to give an accurate depiction of how miticides interact at the colony level. Therefore, the objective of this study was to develop a bioassay cage for testing the toxicity of miticides on honey bees and Varroa mites simultaneously using amitraz as a reference chemical. A 800 mL polypropylene plastic cage holding 100-150 bees was designed and officially named "Apiarium". A comparison of the effects of three subsequent dilutions of amitraz was conducted on: Varroa mites placed in glass vials, honey bees in glass Mason jars, and Varroa-infested bees in Apiariums. Our results indicated cumulative Varroa mortality was dose-dependent in the Apiarium after 4 h and 24 h assessments. Apiarium and glass vial treatments at 24 h also had high mite mortality and a positive polynomial regression between Varroa mortality and amitraz dose rates. Moreover, chemical application in the Apiarium was less toxic for bees compared to the Mason jar method. Considering these results, the Apiarium bioassay provides a simple, cheap and reliable method for simultaneous chemical screening on V. destructor and A. mellifera. Furthermore, as mites and bees are tested together, the Apiarium simulates a colony-like environment that provides a necessary bridge between laboratory bioassay testing and full field experimentation. The versatility of the Apiarium allows researchers to test a multitude of different honey bee bioassay experiments including miticide screening, delivery methods for chemical products, or development of new mite resistance-testing methodology.
Topics: Animals; Bees; Biological Assay; Survival Analysis; Toluidines; Varroidae
PubMed: 33901245
DOI: 10.1371/journal.pone.0250594 -
ACS Applied Materials & Interfaces Feb 2021Nowadays, there is an increasing demand for more accessible routine diagnostics for patients with respect to high accuracy, ease of use, and low cost. However, the...
Nowadays, there is an increasing demand for more accessible routine diagnostics for patients with respect to high accuracy, ease of use, and low cost. However, the quantitative and high accuracy bioassays in large hospitals and laboratories usually require trained technicians and equipment that is both bulky and expensive. In addition, the multistep bioassays and long turnaround time could severely affect the disease surveillance and control especially in pandemics such as influenza and COVID-19. In view of this, a portable, quantitative bioassay device will be valuable in regions with scarce medical resources and help relieve burden on local healthcare systems. Herein, we introduce the MagiCoil diagnostic device, an inexpensive, portable, quantitative, and rapid bioassay platform based on the magnetic particle spectrometer (MPS) technique. MPS detects the dynamic magnetic responses of magnetic nanoparticles (MNPs) and uses the harmonics from oscillating MNPs as metrics for sensitive and quantitative bioassays. This device does not require trained technicians to operate and employs a fully automatic, one-step, and wash-free assay with a user friendly smartphone interface. Using a streptavidin-biotin binding system as a model, we show that the detection limit of the current portable device for streptavidin is 64 nM (equal to 5.12 pmole). In addition, this MPS technique is very versatile and allows for the detection of different diseases just by changing the surface modifications on MNPs. Although MPS-based bioassays show high sensitivities as reported in many literatures, at the current stage, this portable device faces insufficient sensitivity and needs further improvements. It is foreseen that this kind of portable device can transform the multistep, laboratory-based bioassays to one-step field testing in nonclinical settings such as schools, homes, offices, etc.
Topics: Biological Assay; COVID-19; Humans; Hydrodynamics; Influenza, Human; Magnetic Phenomena; Magnetite Nanoparticles; Particle Size; Smartphone; Streptavidin; Surface Properties
PubMed: 33566573
DOI: 10.1021/acsami.0c21040