33 research outputs found

    Cytomegalovirus induces abnormal chondrogenesis and osteogenesis during embryonic mandibular development

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    <p>Abstract</p> <p>Background</p> <p>Human clinical studies and mouse models clearly demonstrate that cytomegalovirus (CMV) disrupts normal organ and tissue development. Although CMV is one of the most common causes of major birth defects in humans, little is presently known about the mechanism(s) underlying CMV-induced congenital malformations. Our prior studies have demonstrated that CMV infection of first branchial arch derivatives (salivary glands and teeth) induced severely abnormal phenotypes and that CMV has a particular tropism for neural crest-derived mesenchyme (NCM). Since early embryos are barely susceptible to CMV infection, and the extant evidence suggests that the differentiation program needs to be well underway for embryonic tissues to be susceptible to viral infection and viral-induced pathology, the aim of this study was to determine if first branchial arch NCM cells are susceptible to mCMV infection prior to differentiation of NCM derivatives.</p> <p>Results</p> <p>E11 mouse mandibular processes (MANs) were infected with mouse CMV (mCMV) for up to 16 days <it>in vitr</it>o. mCMV infection of undifferentiated embryonic mouse MANs induced micrognathia consequent to decreased Meckel's cartilage chondrogenesis and mandibular osteogenesis. Specifically, mCMV infection resulted in aberrant stromal cellularity, a smaller, misshapen Meckel's cartilage, and mandibular bone and condylar dysmorphogenesis. Analysis of viral distribution indicates that mCMV primarily infects NCM cells and derivatives. Initial localization studies indicate that mCMV infection changed the cell-specific expression of FN, NF-ÎşB2, RelA, RelB, and Shh and Smad7 proteins.</p> <p>Conclusion</p> <p>Our results indicate that mCMV dysregulation of key signaling pathways in primarily NCM cells and their derivatives severely disrupts mandibular morphogenesis and skeletogenesis. The pathogenesis appears to be centered around the canonical and noncanonical NF-ÎşB pathways, and there is unusual juxtaposition of abnormal stromal cells and surrounding matrix. Moreover, since it is critically important that signaling molecules are expressed in appropriate cell populations during development, the aberrant localization of components of relevant signaling pathways may reveal the pathogenic mechanism underlying mandibular malformations.</p

    USING A DIGITAL VIDEO CAMERA AS THE SMART SENSOR OF THE SYSTEM FOR AUTOMATIC PROCESS CONTROL OF GRANULAR FODDER MOLDING

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    Summary. The most important operation of granular mixed fodder production is molding process. Properties of granular mixed fodder are defined during this process. They determine the process of production and final product quality. The possibility of digital video camera usage as intellectual sensor for control system in process of production is analyzed in the article. The developed parametric model of the process of bundles molding from granular fodder mass is presented in the paper. Dynamic characteristics of the molding process were determined. A mathematical model of motion of bundle of granular fodder mass after matrix holes was developed. The developed mathematical model of the automatic control system (ACS) with the use of etalon video frame as the set point in the MATLAB software environment was shown. As a parameter of the bundles molding process it is proposed to use the value of the specific area defined in the mathematical treatment of the video frame. The algorithms of the programs to determine the changes in structural and mechanical properties of the feed mass in video frames images were developed. Digital video shooting of various modes of the molding machine was carried out and after the mathematical processing of video the transfer functions for use as a change of adjustable parameters of the specific area were determined. Structural and functional diagrams of the system of regulation of the food bundles molding process with the use of digital camcorders were built and analyzed. Based on the solution of the equations of fluid dynamics mathematical model of bundle motion after leaving the hole matrix was obtained. In addition to its viscosity, creep property was considered that is characteristic of the feed mass. The mathematical model ACS of the bundles molding process allowing to investigate transient processes which occur in the control system that uses a digital video camera as the smart sensor was developed in Simulink. Decision algorithm for generating regulatory impact when using a digital video camera as the smart sensor was developed. The developed automatic control systems (ACS) of the process of granular fodder molding based on the use of digital video camera as an intelligent sensor was described

    The Composition of Melt Inclusions in Minerals from Tephra of the Soil–Pyroclastic Cover of Simushir Island (Central Kuril Islands)

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    The compositions of approximately 70 naturally quenched melt inclusions in olivine, clinopyroxene, orthopyroxene, and plagioclase phenocrysts from tephra of the soil–pyroclastic cover of Simushir Island (Central Kuril Islands) were studied. The concentrations of the major rock-forming components, H2O, S, and Cl were analyzed in inclusions. The reconstructed melts contain 48.6–78.4 wt % SiO2, 0.3–8.26 wt % MgO, and 0.12–1.72 wt % K2O. The concentration of S and Cl in the melts changes regularly with increasing SiO2 content: from 0.14 to ~0.02 wt % S and from ~0.05 to ~0.28 wt % Cl. The content of H2O in parental melts is 4.2–4.5 wt %

    Quasielastic neutron scattering and diffusion in liquid lithium and lithium–hydrogen melt

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    International audienceNeutron quasielastic scattering experiments on liquid lithium (at 500 and 830 K) and a lithium–hydrogen melt (99 at.% Li 7 and 1 at.% H at 830 K) have been performed. The characteristics of the diffusion mobility for lithium and hydrogen atoms have been extracted from the experimental results and analyzed with the use of phenomenological and theoretical models. The self-diffusion coefficient in liquid lithium obtained for both temperatures is in agreement with values in the literature. The mechanism of hydrogen diffusion mobility in liquid lithium is discussed. It has been concluded that the hydrogen in the liquid lithium exists and diffuses in the form of the hydride LiH
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