1. Articles in category: Developmental Biology

    1-24 of 232 1 2 3 4 5 6 7 8 9 10 »
    1. Optical Modalities for Embryonic Imaging

      Optical Modalities for Embryonic Imaging

      tudies of disease etiology often rely on the murine (mouse) model, which provides valuable genotypic information. Yet associated phenotypic information from murine embryos is often lacking. Of the various techniques that have been proposed for imaging such embryos, optical modalities may provide the best compromise among speed, penetration depth and resolution. This year, we developed approaches to improve embryonic imaging with optical coherence tomography (OCT), 1 and also provided a detailed comparison of OCT and another modality, optical projection tomography (OPT), in murine-embryo studies. 2 Most commonly used for ophthalmological imaging, 3 OCT has proved a powerful embryonic-imaging modality as ...

      Read Full Article
    2. A method to study the hemodynamics of chicken embryo's aortic arches using optical coherence tomography

      A method to study the hemodynamics of chicken embryo's aortic arches using optical coherence tomography

      Congenital cardiovascular defects are the leading cause of birth defect related death. It has been hypothesized that fluid mechanical forces of embryonic blood flow affect cardiovascular development and play a role in congenital malformations. Studies in small animal embryos can improve our understanding of congenital malformations and can lead to better treatment. We present a feasibility study in which high-resolution optical coherence tomography (OCT) and computational fluid dynamics (CFD) are combined to provide quantitative analysis of the embryonic flow mechanics and the associated anatomy in a small animal model.

      Read Full Article
    3. Imaging the adult zebrafish cone mosaic using optical coherence tomography

      Imaging the adult zebrafish cone mosaic using optical coherence tomography

      Zebrafish ( Danio rerio ) provide many advantages as a model organism for studying ocular disease and development, and there is great interest in the ability to non-invasively assess their photoreceptor mosaic. Despite recent applications of scanning light ophthalmoscopy, fundus photography, and gonioscopy to in vivo imaging of the adult zebrafish eye, current techniques either lack accurate scaling information (limiting quantitative analyses) or require euthanizing the fish (precluding longitudinal analyses). Here we describe improved methods for imaging the adult zebrafish retina using spectral domain optical coherence tomography (OCT). Transgenic fli1:eGFP zebrafish were imaged using the Bioptigen Envisu R2200 broadband source OCT ...

      Read Full Article
    4. Extended-focus optical coherence microscopy for high-resolution imaging of the murine brain

      Extended-focus optical coherence microscopy for high-resolution imaging of the murine brain

      We propose a new method and optical instrumentation for mouse brain imaging based on extended-focus optical coherence microscopy. This in vivo imaging technique allows the evaluation of the cytoarchitecture at cellular level and the circulation system dynamics in three dimensions. This minimally invasive and non-contact approach is performed without the application of contrasting agents. The optical design achieved a resolution of 2.2 μm over a distance of 800 μm, which was sufficient to obtain a detailed three-dimensional image of a wild-type mouse’s brain down to the layer III of the cortex. Intrinsically contrasted microvessels and structures similar to ...

      Read Full Article
    5. The adult zebrafish retina: In vivo optical sectioning with Confocal Scanning Laser Ophthalmoscopy and Spectral-Domain Optical Coherence Tomography

      The adult zebrafish retina: In vivo optical sectioning with Confocal Scanning Laser Ophthalmoscopy and Spectral-Domain Optical Coherence Tomography

      Non-invasive imaging is an invaluable diagnostic tool in ophthalmology. Two imaging devices, the scanning laser ophthalmoscope (SLO) and spectral domain optical coherence tomography (SDOCT), emerged from the clinical realm to provide research scientists with a real-time view of ocular morphology in living animals. We utilized these two independent imaging modalities in a complementary manner to perform in vivo optical sectioning of the adult zebrafish retina. Due to the very high optical power of the zebrafish lens, the confocal depth of field is narrow, allowing for detailed en face views of specific retinal layers, including the cone mosaic. Moreover, we demonstrate ...

      Read Full Article
    6. Optical Coherence Tomography for Brain Imaging and Developmental Biology

      Optical Coherence Tomography for Brain Imaging and Developmental Biology

      Optical coherence tomography (OCT) is a promising research tool for brain imaging and developmental biology. Serving as a three-dimensional optical biopsy technique, OCT provides volumetric reconstruction of brain tissues and embryonic structures with micrometer resolution and video rate imaging speed. Functional OCT enables label-free monitoring of hemodynamic and metabolic changes in the brain in vitro and in vivo in animal models. Due to its noninvasiveness nature, OCT enables longitudinal imaging of developing specimens in vivo without potential damage from surgical operation, tissue fixation and processing, and staining with exogenous contrast agents. In this paper, various OCT applications in brain imaging ...

      Read Full Article
    7. Time-Series Interactions of Gene Expression, Vascular Growth and Hemodynamics during Early Embryonic Arterial Development

      Time-Series Interactions of Gene Expression, Vascular Growth and Hemodynamics during Early Embryonic Arterial Development

      The role of hemodynamic forces within the embryo as biomechanical regulators for cardiovascular morphogenesis, growth, and remodeling is well supported through the experimental studies. Furthermore, clinical experience suggests that perturbed flow disrupts the normal vascular growth process as one etiology for congenital heart diseases (CHD) and for fetal adaptation to CHD. However, the relationships between hemodynamics, gene expression and embryonic vascular growth are poorly defined due to the lack of concurrent, sequential in vivo data. In this study, a long-term, time-lapse optical coherence tomography (OCT) imaging campaign was conducted to acquire simultaneous blood velocity, pulsatile micro-pressure and morphometric data for ...

      Read Full Article
      Mentions: Thorlabs
    8. Multi-modality Optical Imaging of Rat Kidney Dysfunction: In Vivo Response to Various Ischemia Times

      Multi-modality Optical Imaging of Rat Kidney Dysfunction: In Vivo Response to Various Ischemia Times

      We observed in vivo kidney dysfunction with various ischemia times at 30, 75, 90, and 120 min using multi-modality optical imaging: optical coherence tomography (OCT), Doppler OCT (DOCT), and two-photon microscopy (TPM). We imaged the renal tubule lumens and glomerulus at several areas of each kidney before, during, and after ischemia of 5-month-old female Munich-Wistar rats. For animals with 30 and 75 min ischemia times, we observed that all areas were recovered after ischemia, that tubule lumens were re-opened and the blood flow of the glomerulus was re-established. For animals with 90 and 120 min ischemia times, we observed unrecovered ...

      Read Full Article
    9. The University of California at Davis Receives NIH Grant for the Rodent Eye as a Non-Invasive Window for Understanding Cancer Nanotheraputics

      The University of California at Davis Receives NIH Grant for the Rodent Eye as a Non-Invasive Window for Understanding Cancer Nanotheraputics

      The University of California at Davis Receives a 2016 NIH Grant for $586,386 for The Rodent Eye as a Non-Invasive Window for Understanding Cancer Nanotheraputics. The principal investigator is Kit Lam. The program began in 2015 and ends in 2020. Below is a summary of the proposed work. The rodent eye as a non-invasive window for understanding cancer nanotherapeutics Abstract: We propose to use the mouse eye as a non-surgical window for highly efficient, optical investigation of subretinal xenograft models and nanodelivery, using a state-of-the-art ocular imager, "EyePod". The EyePod employs single-cell resolution intravital confocal microscopy and optical coherence ...

      Read Full Article
    10. Long-term in vivo monitoring of injury induced brain regeneration of the adult zebrafish by using spectral domain optical coherence tomography

      Long-term in vivo monitoring of injury induced brain regeneration of the adult zebrafish by using spectral domain optical coherence tomography

      Brain regenerative studies require precise visualization of the morphological structures. However, few imaging methods can effectively detect the adult zebrafish brain in real time with high resolution and good penetration depth. Long-term in vivo monitoring of brain injuries and brain regeneration on adult zebrafish is achieved in this study by using 1325 nm spectral-domain optical coherence tomography (SD-OCT). The SD-OCT is able to noninvasively visualize the skull injury and brain lesion of adult zebrafish. Valuable phenomenon such as the fractured skull, swollen brain tissues, and part of the brain regeneration process can be conducted based on the SD-OCT images at ...

      Read Full Article
    11. Case Western Reserve University Receives NIH Grant for Integrated Imaging of the Form and Function of the Beating Embryonic Heart

      Case Western Reserve University Receives NIH Grant for Integrated Imaging of the Form and Function of the Beating Embryonic Heart

      Case Western Reserve University Receives a 2016 NIH Grant for $356,784 for Integrated Imaging of the Form and Function of the Beating Embryonic Heart. The principal investigator is Andrew Rollins. The program began in 2006 and ends in 2017. Below is a summary of the proposed work. Congenital heart defects (CHDs) afflict 36,000 babies born in the US each year and survivors often require several surgical interventions in their shortened lifetime. Despite continuous efforts, the mechanisms leading to CHDs remain largely unclear. In part, this is because most developmental cardiology studies fail to address the influential role of ...

      Read Full Article
    12. Live four-dimensional optical coherence tomography reveals embryonic cardiac phenotype in mouse mutant

      Live four-dimensional optical coherence tomography reveals embryonic cardiac phenotype in mouse mutant

      Efficient phenotyping of developmental defects in model organisms is critical for understanding the genetic specification of normal development and congenital abnormalities in humans. We previously reported that optical coherence tomography (OCT) combined with live embryo culture is a valuable tool for mouse embryo imaging and four-dimensional (4-D) cardiodynamic analysis; however, its capability for analysis of mouse mutants with cardiac phenotypes has not been previously explored. Here, we report 4-D (three-dimensional+time) OCT imaging and analysis of the embryonic heart in a Wdr19 mouse mutant, revealing a heart looping defect. Quantitative analysis of cardiac looping revealed a statistically significant difference between ...

      Read Full Article
    13. Characterization of zebrafish larvae suction feeding flow using μPIV and optical coherence tomography

      Characterization of zebrafish larvae suction feeding flow using μPIV and optical coherence tomography

      The hydrodynamics of suction feeding is critical for the survival of fish larvae; failure to capture food during the onset of autonomous feeding can rapidly lead to starvation and mortality. Fluid mechanics experiments that investigate the suction feeding of suspended particles are limited to adult fishes, which operate at large Reynolds numbers. This manuscript presents the first literature results in which the external velocity fields generated during suction feeding of early zebrafish larvae (2500–20,000 μm total length) are reported using time-resolved microscopic particle image velocimetry. For the larval stages studied, the maximum peak suction velocity of the inflow ...

      Read Full Article
    14. High-resolution contrast-enhanced optical coherence tomography in mice retinae

      High-resolution contrast-enhanced optical coherence tomography in mice retinae

      Optical coherence tomography (OCT) is a noninvasive interferometric imaging modality providing anatomical information at depths of millimeters and a resolution of micrometers. Conventional OCT images limit our knowledge to anatomical structures alone, without any contrast enhancement. Therefore, here we have, for the first time, optimized an OCT-based contrast-enhanced imaging system for imaging single cells and blood vessels in vivo inside the living mouse retina at subnanomolar sensitivity. We used bioconjugated gold nanorods (GNRs) as exogenous OCT contrast agents. Specifically, we used anti-mouse CD45 coated GNRs to label mouse leukocytes and mPEG-coated GNRs to determine sensitivity of GNR detection in vivo ...

      Read Full Article
    15. Massachusetts General Hospital Receives NIH Grant for Cardiac MRI-Tractography In Vivo: Integrated Imaging of Structure and Function

      Massachusetts General Hospital Receives NIH Grant for Cardiac MRI-Tractography In Vivo: Integrated Imaging of Structure and Function

      Massachusetts General Hospital Receives a 2016 NIH Grant for $742,986 for Cardiac MRI-Tractography In Vivo: Integrated Imaging of Structure and Function. The principal investigator is David Sosnovik. The program began in 2013 and ends in 2017. Below is a summary of the proposed work. Pressure overload of the left and right ventricles initially leads to adaptive hypertrophy. This, however, is frequently followed by maladaptive hypertrophy, heart failure and death. We hypothesize here that changes in 3D myocardial fiber architecture play a significant role in the deleterious transition from adaptive to maladaptive hypertrophy and heart failure. We further hypothesize that ...

      Read Full Article
    16. Optical coherence tomography for embryonic imaging: a review

      Optical coherence tomography for embryonic imaging: a review

      Embryogenesis is a highly complex and dynamic process, and its visualization is crucial for understanding basic physiological processes during development and for identifying and assessing possible defects, malformations, and diseases. While traditional imaging modalities, such as ultrasound biomicroscopy, micro-magnetic resonance imaging, and micro-computed tomography, have long been adapted for embryonic imaging, these techniques generally have limitations in their speed, spatial resolution, and contrast to capture processes such as cardiodynamics during embryogenesis. Optical coherence tomography (OCT) is a noninvasive imaging modality with micrometer-scale spatial resolution and imaging depth up to a few millimeters in tissue. OCT has bridged the gap between ...

      Read Full Article
    17. Retroreflective-type Janus microspheres as a novel contrast agent for enhanced optical coherence tomography

      Retroreflective-type Janus microspheres as a novel contrast agent for enhanced optical coherence tomography

      Working principle and SEM image of Janus microsphere (top). Enhanced OCT imaging (bottom) of Janus microspheres in zebrafish stomach (blue dash line) and sinusoids (green arrows) of nude liver. Optical coherence tomography (OCT) is a well-developed technology that utilizes near-infrared light to reconstruct three-dimensional images of biological tissues with micrometer resolution. Improvements of the imaging contrast of the OCT technique are able to further widen its extensive biomedical applications. In this study, Janus microspheres were developed and used as a positive contrast agent for enhanced OCT imaging. Phantom and ex vivo liver tissue experiments as well as in vivo animal ...

      Read Full Article
    18. Applicability, usability, and limitations of murine embryonic imaging with optical coherence tomography and optical projection tomography

      Applicability, usability, and limitations of murine embryonic imaging with optical coherence tomography and optical projection tomography

      We present an analysis of imaging murine embryos at various embryonic developmental stages (embryonic day 9.5, 11.5, and 13.5) by optical coherence tomography (OCT) and optical projection tomography (OPT). We demonstrate that while OCT was capable of rapid high-resolution live 3D imaging, its limited penetration depth prevented visualization of deeper structures, particularly in later stage embryos. In contrast, OPT was able to image the whole embryos, but could not be used in vivo because the embryos must be fixed and cleared. Moreover, the fixation process significantly altered the embryo morphology, which was quantified by the volume of ...

      Read Full Article
    19. Bright-Field Imaging and Optical Coherence Tomography of the Mouse Posterior Eye

      Bright-Field Imaging and Optical Coherence Tomography of the Mouse Posterior Eye

      Noninvasive live imaging has been used extensively for ocular phenotyping in mouse vision research. Bright-field imaging and optical coherence tomography (OCT) are two methods that are particularly useful for assessing the posterior mouse eye (fundus), including the retina, retinal pigment epithelium, and choroid, and are widely applied due to the commercial availability of sophisticated instruments and software. Here, we provide a guide to using these approaches with an emphasis on post-acquisition image processing using Fiji, a bundled version of the Java-based public domain software ImageJ. A bright-field fundus imaging protocol is described for acquisition of multi-frame videos, followed by image ...

      Read Full Article
    20. CUG-BP, Elav-like family member 1 (CELF1) is required for normal myofibrillogenesis, morphogenesis, and contractile function in the embryonic heart

      CUG-BP, Elav-like family member 1 (CELF1) is required for normal myofibrillogenesis, morphogenesis, and contractile function in the embryonic heart

      Background : CUG-BP, Elav-like family member 1 (CELF1) is a multifunctional RNA binding protein found in a variety of adult and embryonic tissues. In the heart, CELF1 is found exclusively in the myocardium. However, the roles of CELF1 during cardiac development have not been completely elucidated. Results : Myofibrillar organization is disrupted and proliferation is reduced following knockdown of CELF1 in cultured chicken primary embryonic cardiomyocytes. In vivo knockdown of Celf1 in developing Xenopus laevis embryos resulted in myofibrillar disorganization and a trend towards reduced proliferation in heart muscle, indicating conserved roles for CELF1 orthologs in embryonic cardiomyocytes. Loss of Celf1 also ...

      Read Full Article
    21. Effect of Outflow Tract Banding on Embryonic Cardiac Hemodynamics

      Effect of Outflow Tract Banding on Embryonic Cardiac Hemodynamics

      We analyzed heart wall motion and blood flow dynamics in chicken embryos using in vivo optical coherence tomography (OCT) imaging and computational fluid dynamics (CFD) embryo-specific modeling. We focused on the heart outflow tract (OFT) region of day 3 embryos, and compared normal (control) conditions to conditions after performing an OFT banding intervention, which alters hemodynamics in the embryonic heart and vasculature. We found that hemodynamics and cardiac wall motion in the OFT are affected by banding in ways that might not be intuitive a priori . In addition to the expected increase in ventricular blood pressure, and increase blood flow ...

      Read Full Article
    22. 4D imaging of cardiac trabeculae contracting in vitro using gated OCT

      4D imaging of cardiac trabeculae contracting in vitro using gated OCT

      Cardiac trabeculae are widely used as experimental muscle preparations for studying heart muscle. However, their geometry (diameter, length, and shape) can vary not only amongst samples, but also within a sample, leading to inaccuracies in estimating their stress production, volumetric energy output, and/or oxygen consumption. Hence, it is desirable to have a system that can accurately image each trabecula in vitro during an experiment. To this end, we constructed an optical coherence tomography (OCT) system and implemented a gated imaging procedure to image actively contracting trabeculae and reconstruct their time-varying geometry. By imaging a single cross section while monitoring ...

      Read Full Article
    23. Michael Jenkins Wins American Association of Anatomists (AAA) Young Investigator Award

      Michael Jenkins Wins American Association of Anatomists (AAA) Young Investigator Award

      Ceremony at AAA's 2016 annual meeting at Experimental Biology (EB) in San Diego, CA. The ceremony is being held at The Marriot Marquis San Diego Marina on Tuesday, April 5, 2016, at 7pm. Young Investigator awards recognize investigators in the early stages of their careers who have made important contributions to biomedical science through their research in cell/molecular biology, comparative neuroanatomy, developmental biology, or the morphological sciences. The 2016 Young Investigator Award winners are:...Michael Jenkins, Ph.D. , of Case Western Reserve University , will be honored with a plaque for his early contributions to the field of developmental ...

      Read Full Article
    24. Particle streak velocimetry-optical coherence tomography: a novel method for multidimensional imaging of microscale fluid flows

      Particle streak velocimetry-optical coherence tomography: a novel method for multidimensional imaging of microscale fluid flows

      We present a new OCT method for flow speed quantification and directional velocimetry: particle streak velocimetry-OCT (PSV-OCT). PSV-OCT generates two-dimensional, 2.5-vector component ( v x ,| v y |, v z ) maps of microscale flow velocity fields. Knowledge of 2.5-vector components also enables the estimation of total flow speed. The enabling insight behind PSV-OCT is that tracer particles in sparsely-seeded fluid flow trace out streaks in ( x,z,t )-space. The streak orientations in x-t and z-t yield v x and v z , respectively. The in-plane ( x-z plane) residence time yields the out-of-plane speed | v y |. Vector component values are generated ...

      Read Full Article
    1-24 of 232 1 2 3 4 5 6 7 8 9 10 »
  1. Categories

    1. Applications:

      Art, Cardiology, Dentistry, Dermatology, Developmental Biology, Gastroenterology, Gynecology, Microscopy, NDE/NDT, Neurology, Oncology, Ophthalmology, Other Non-Medical, Otolaryngology, Pulmonology, Urology
    2. Business News:

      Acquisition, Clinical Trials, Funding, Other Business News, Partnership, Patents
    3. Technology:

      Broadband Sources, Probes, Tunable Sources
    4. Miscellaneous:

      Jobs & Studentships, Student Theses, Textbooks
  2. Popular Articles

  3. Organizations in the News

    1. (1 articles) University of Houston
    2. (1 articles) Baylor College of Medicine
  4. People in the News

    1. (1 articles) Mary E. Dickinson
    2. (1 articles) Chen Wu
    3. (1 articles) Manmohan Singh
    4. (1 articles) Kirill V. Larin
    5. (1 articles) Shang Wang
    6. (1 articles) Irina V. Larina