J Mech Behav Biomed Mater
September 2024
Mechanical properties are essential for the biological activities of cells, and they have been shown to be affected by diseases. Therefore, accurate mechanical characterization is important for studying the cell lifecycle, cell-cell interactions, and disease diagnosis. While the cytoskeleton and actin cortex are typically the primary structural stiffness contributors in most live cells, oocytes possess an additional extracellular layer known as the vitelline membrane (VM), or envelope, which can significantly impact their overall mechanical properties.
View Article and Find Full Text PDFBackground: The genes involved in inner ear development and maintenance of the adult organ have yet to be fully characterized. Previous genetic analysis has emphasized the early development that gives rise to the otic vesicle. This study aimed to bridge the knowledge gap and identify candidate genes that are expressed as the auditory and vestibular sensory organs continue to grow and develop until the systems reach postmetamorphic maturity.
View Article and Find Full Text PDFAstrocytoma is an invasive carcinoma occurring in the nervous system and currently lacks effective treatment options. A deeper understanding of the mechanisms of tumorigenesis and tumor progression is needed in order to develop novel therapeutic strategies. Recent advances in culture systems have demonstrated that the use of three-dimensional (3D) culture models could be more relevant for this purpose as compared to monolayer or two-dimensional (2D) models due to their resemblance to cancer pathology.
View Article and Find Full Text PDFBackground: The potential for astrocyte participation in central nervous system recovery is highlighted by in vitro experiments demonstrating their capacity to transdifferentiate into neurons. Understanding astrocyte plasticity could be advanced by comparing astrocytes with stem cells. RNA sequencing (RNA-seq) is ideal for comparing differences across cell types.
View Article and Find Full Text PDFTriple negative breast cancer (TNBC) is a belligerent carcinoma that is unresponsive to targeted receptor therapies. Development of new treatment strategies would benefit from an expanded repertoire of cell culture systems, such as those that support tridimensional growth in the presence of hydrogel scaffolds. To this end, we established protocols for maintenance of the TNBC cell line HCC70 in monolayer culture and in a commercially available basement membrane matrix hydrogel.
View Article and Find Full Text PDFThe cytoskeletal protein tubulin plays an integral role in the functional specialization of many cell types. In the central nervous system, post-translational modifications and the expression of specific tubulin isotypes in neurons have been analyzed in greater detail than in their astrocytic counterparts. In this study, we characterized post-translational specifications of tubulin in human astrocytes using the normal human astrocyte (NHA; Lonza) commercial cell line of fetal origin.
View Article and Find Full Text PDFBiomaterial scaffolds have the potential to enhance neuronal development and regeneration. Understanding the genetic responses of astrocytes and neurons to biomaterials could facilitate the development of synthetic environments that enable the specification of neural tissue organization with engineered scaffolds. In this study, we used high throughput transcriptomic and imaging methods to determine the impact of a hydrogel, PuraMatrix™, on human glial cells .
View Article and Find Full Text PDFThe amphibian Xenopus offers a unique model system for uncovering the genetic basis of auditory and vestibular function in an organism that is well-suited for experimental manipulation during animal development. However, many procedures for analyzing gene expression in the peripheral auditory and vestibular systems mandate the ability to isolate intact RNA from inner ear tissue. Methods presented here facilitate preparation of high-quality inner ear RNA from larval and post-metamorphic Xenopus specimens that can be used for a variety of purposes.
View Article and Find Full Text PDFBMC Res Notes
November 2015
Background: Auditory and vestibular disorders are prevalent sensory disabilities caused by genetic and environmental (noise, trauma, chemicals) factors that often damage mechanosensory hair cells of the inner ear. Development of treatments for inner ear disorders of hearing and balance relies on the use of animal models such as fish, amphibians, reptiles, birds, and non-human mammals. Here, we aimed to augment the utility of the genus Xenopus for uncovering genetic mechanisms essential for the maintenance of inner ear structure and function.
View Article and Find Full Text PDFBackground: The senses of hearing and balance depend upon mechanoreception, a process that originates in the inner ear and shares features across species. Amphibians have been widely used for physiological studies of mechanotransduction by sensory hair cells. In contrast, much less is known of the genetic basis of auditory and vestibular function in this class of animals.
View Article and Find Full Text PDFThe Xenopus inner ear provides a useful model for studies of hearing and balance because it shares features with the mammalian inner ear, and because amphibians are capable of regenerating damaged mechanosensory hair cells. The structure and function of many proteins necessary for inner ear function have yet to be elucidated and require methods for analysis. To this end, we seek to characterize Xenopus inner ear genes outside of the animal model through heterologous expression in cell lines.
View Article and Find Full Text PDFQuantum dots (QDs) are semiconductor nanocrystals with extensive imaging and diagnostic capabilities, including the potential for single molecule tracking. Commercially available QDs offer distinct advantages over organic fluorophores, such as increased photostability and tunable emission spectra, but their cadmium selenide (CdSe) core raises toxicity concerns. For this reason, replacements for CdSe-based QDs have been sought that can offer equivalent optical properties.
View Article and Find Full Text PDFWe aim to determine the biological relevance of genes identified through microarray-mediated transcriptional profiling of Xenopus sensory organs and brain. Difficulties with genetic data analysis arise because of limitations in probe set annotation and the lack of a universal gene nomenclature. To overcome these impediments, we used sequence based and semantic linking methods in combination with computational approaches to augment probe set annotation on a commercially available microarray.
View Article and Find Full Text PDFThe amphibian Xenopus offers a unique model system for uncovering the genetic basis of auditory and vestibular function in an organism that is well-suited for experimental manipulation during animal development. However, many procedures for analyzing gene expression in the peripheral auditory and vestibular systems mandate the ability to isolate intact RNA from inner ear tissue. Methods presented here facilitate preparation of high quality inner ear RNA from larval and post-metamorphic Xenopus specimens that can be used for a variety of purposes.
View Article and Find Full Text PDFInt J Dev Biol
September 2007
The auditory and vestibular endorgans of the inner ear which are essential for the senses of hearing and balance form early during development when the otocyst undergoes a period of rapid growth and compartmentalization. Here we show the spatial and temporal patterns of proliferating cells in the Xenopus laevis inner ear as this organ develops from an otic vesicle at stage 31 until stage 47, an age at which compartmentalization and the initial appearance of sensory structures are evident. Sites of new cell production were identified in specimens at stages 31, 37, 42, 45 and 47 using immunohistochemical methods to detect bromodeoxyuridine (BrdU) incorporation three hours after exposure to this thymidine analogue.
View Article and Find Full Text PDFIEEE Trans Nanobioscience
December 2006
Quantum dots (QDs) are useful biological probes because of the increased photostability and quantum efficiency they offer over organic fluorophores. However, toxicity concerns arise because the QD core is composed of cadmium and selenium, metals known to be unsafe for humans and animals. We investigated the feasibility of quantum dots as biological labels for imaging studies of inner ear and kidney, tissues that share a polarized epithelial arrangement and drug susceptibility.
View Article and Find Full Text PDFThe formation of the eight independent endorgan compartments (sacculus, utricle, horizontal canal, anterior canal, posterior canal, lagena, amphibian papilla, and basilar papilla) of the Xenopus laevis inner ear is illustrated as the otic vesicle develops into a complex labyrinthine structure. The morphology of transverse sections and whole-mounts of the inner ear was assessed in seven developmental stages (28, 31, 37, 42, 45, 47, 50) using brightfield and laser scanning confocal microscopy. The presence of mechanosensory hair cells in the sensory epithelia was determined by identification of stereociliary bundles in cryosectioned tissue and whole-mounts of the inner ear labeled with the fluorescent F-actin probe Alexa-488 phalloidin.
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