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Sample records for nonplanar secretory iga2

  1. Degradation of human secretory IgA1 and IgA2 by Entamoeba histolytica surface-associated proteolytic activity.

    PubMed

    Garcia-Nieto, Rosa Maria; Rico-Mata, Rosa; Arias-Negrete, Sergio; Avila, Eva E

    2008-12-01

    The protozoan Entamoeba histolytica is the etiological agent of amebiasis, an infection with high prevalence worldwide. The host-ameba relationship outcome depends on parasite and host factors, and among these is secretory IgA. These antibodies reduce mucosal colonization by pathogens and neutralize a variety of toxins and enzymes. The functionality of secretory IgA depends on its integrity. Some bacteria produce IgA proteases that cleave mainly the IgA1 subclass; live E. histolytica trophozoites, and other ameba fractions are also able to degrade human IgA. The aim of this study was to determine if serum and secretory IgA, its subclasses and secretory component, are degraded by cysteine proteases, which are present and active on the surface of glutaraldehyde-fixed amebas. It was observed that secretory IgA1, IgA2, free and IgA-bound secretory component were degraded by E. histolytica surface-associated cysteine proteinases. Secretory IgA2, although it was degraded, conserved its ability to agglutinate live amebas better than IgA1. Therefore, while specificity of known ameba cysteine proteases is cathepsin B-like and is different from bacterial IgA proteases, IgA2 was functionally more resistant than IgA1 to ameba surface-associated cysteine protease degradation, similar to the greater resistance of IgA2 to bacterial IgA-specific proteases.

  2. Expression of homing receptors on IgA1 and IgA2 plasmablasts in blood reflects differential distribution of IgA1 and IgA2 in various body fluids.

    PubMed

    Pakkanen, Sari H; Kantele, Jussi M; Moldoveanu, Zina; Hedges, Spencer; Häkkinen, Miikka; Mestecky, Jiri; Kantele, Anu

    2010-03-01

    Although secretory IgA is the most abundantly produced Ig isotype, the mechanisms underlying the differential distribution of IgA subclasses in various body fluids remain unclear. To explore these mechanisms, we examined the distribution of IgA subclasses, the influence of the nature and sites of encounters with antigens, and the correlation between IgA subclass distribution and homing potentials of circulating IgA plasmablasts. IgA1 predominated in serum, tears, nasal wash fluid, and saliva; the levels of IgA1 and IgA2 were comparable in vaginal wash fluid; and IgA2 predominated in intestinal lavage fluids. Seventy-one percent of circulating IgA plasmablasts secreted IgA1. The intestinal homing receptor (HR), alpha4beta7, was expressed more frequently on IgA2 than on IgA1 plasmablasts, with no differences in the expression of other HRs. IgA subclass distribution among circulating antigen-specific antibody-secreting cells (ASC) was dependent on the nature of the antigen: following vaccination with Salmonella enterica serovar Typhi, unconjugated pneumococcal polysaccharide, or Haemophilus influenzae polysaccharide-diphtheria toxoid conjugate, the proportions of specific IgA1 ASC were 74%, 47%, 56%, and 80%, respectively. HR expression depended on the route of administration: expression of HRs was different after oral than after parenteral vaccination, while no difference was seen between HR expression of antigen-specific IgA1 and IgA2 ASC induced via the same route. The key factors determining IgA subclass distribution in a given secretion are the nature of the antigens encountered at a particular site and the site-specific homing instructions given to lymphocytes at that site. These two factors are reflected as differences in the homing profiles of the total populations of circulating IgA1 and IgA2 plasmablasts.

  3. Highly nonplanar lifting systems

    NASA Technical Reports Server (NTRS)

    Kroo, Ilan; McMasters, John; Smith, Stephen C.

    1996-01-01

    This paper deals with nonplanar wing concepts -- their advantages and possible applications in a variety of aircraft designs. A brief review and assessment of several concepts from winglets to ring wings is followed by a more detailed look at two recent ideas: exploiting nonplanar wakes to reduce induced drag, and applying a 'C-wing' design to large commercial transports. Results suggest that potential efficiency gains may be significant, while several nonaerodynamic characteristics are particularly interesting.

  4. Psychological distress and salivary secretory immunity.

    PubMed

    Engeland, C G; Hugo, F N; Hilgert, J B; Nascimento, G G; Junges, R; Lim, H-J; Marucha, P T; Bosch, J A

    2016-02-01

    Stress-induced impairments of mucosal immunity may increase susceptibility to infectious diseases. The present study investigated the association of perceived stress, depressive symptoms, and loneliness with salivary levels of secretory immunoglobulin A (S-IgA), the subclasses S-IgA1, S-IgA2, and their transporter molecule Secretory Component (SC). S-IgA/SC, IgA1/SC and IgA2/SC ratios were calculated to assess the differential effects of stress on immunoglobulin transport versus availability. This study involved 113 university students, in part selected on high scores on the UCLA Loneliness Scale and/or the Beck Depression Inventory. Stress levels were assessed using the Perceived Stress Scale. Unstimulated saliva was collected and analysed for total S-IgA and its subclasses, as well as SC and total salivary protein. Multiple linear regression analyses, adjusted for gender, age, health behaviours, and concentration effects (total protein) revealed that higher perceived stress was associated with lower levels of IgA1 but not IgA2. Perceived stress, loneliness and depressive symptoms were all associated with lower IgA1/SC ratios. Surprisingly, higher SC levels were associated with loneliness and depressive symptoms, indicative of enhanced transport activity, which explained a lower IgA1/SC ratio (loneliness and depression) and IgA2/SC ratio (depression). This is the first study to investigate the effects of protracted psychological stress across S-IgA subclasses and its transporter SC. Psychological stress was negatively associated with secretory immunity, specifically IgA1. The lower immunoglobulin/transporter ratio that was associated with higher loneliness and depression suggested a relative immunoglobulin depletion, whereby availability was not keeping up with enhanced transport demand.

  5. Secretory autophagy.

    PubMed

    Ponpuak, Marisa; Mandell, Michael A; Kimura, Tomonori; Chauhan, Santosh; Cleyrat, Cédric; Deretic, Vojo

    2015-08-01

    Autophagy, once viewed exclusively as a cytoplasmic auto-digestive process, has its less intuitive but biologically distinct non-degradative roles. One manifestation of these functions of the autophagic machinery is the process termed secretory autophagy. Secretory autophagy facilitates unconventional secretion of the cytosolic cargo such as leaderless cytosolic proteins, which unlike proteins endowed with the leader (N-terminal signal) peptides cannot enter the conventional secretory pathway normally operating via the endoplasmic reticulum and the Golgi apparatus. Secretory autophagy may also export more complex cytoplasmic cargo and help excrete particulate substrates. Autophagic machinery and autophagy as a process also affect conventional secretory pathways, including the constitutive and regulated secretion, as well as promote alternative routes for trafficking of integral membrane proteins to the plasma membrane. Thus, autophagy and autophagic factors are intimately intertwined at many levels with secretion and polarized sorting in eukaryotic cells. PMID:25988755

  6. Non-planar chemical preconcentrator

    DOEpatents

    Manginell, Ronald P.; Adkins, Douglas R.; Sokolowski, Sara S.; Lewis, Patrick R.

    2006-10-10

    A non-planar chemical preconcentrator comprises a high-surface area, low mass, three-dimensional, flow-through sorption support structure that can be coated or packed with a sorptive material. The sorptive material can collect and concentrate a chemical analyte from a fluid stream and rapidly release it as a very narrow temporal plug for improved separations in a microanalytical system. The non-planar chemical preconcentrator retains most of the thermal and fabrication benefits of a planar preconcentrator, but has improved ruggedness and uptake, while reducing sorptive coating concerns and extending the range of collectible analytes.

  7. Evidence for a nonplanar amplituhedron

    NASA Astrophysics Data System (ADS)

    Bern, Zvi; Herrmann, Enrico; Litsey, Sean; Stankowicz, James; Trnka, Jaroslav

    2016-06-01

    The scattering amplitudes of planar mathcal{N} = 4 super-Yang-Mills exhibit a number of remarkable analytic structures, including dual conformal symmetry and logarithmic singularities of integrands. The amplituhedron is a geometric construction of the integrand that incorporates these structures. This geometric construction further implies the amplitude is fully specified by constraining it to vanish on spurious residues. By writing the amplitude in a dlog basis, we provide nontrivial evidence that these analytic properties and "zero conditions" carry over into the nonplanar sector. This suggests that the concept of the amplituhedron can be extended to the nonplanar sector of mathcal{N} = 4 super-Yang-Mills theory.

  8. Evidence for a nonplanar amplituhedron

    DOE PAGES

    Bern, Zvi; Herrmann, Enrico; Litsey, Sean; Stankowicz, James; Trnka, Jaroslav

    2016-06-17

    The scattering amplitudes of planar N = 4 super-Yang-Mills exhibit a number of remarkable analytic structures, including dual conformal symmetry and logarithmic singularities of integrands. The amplituhedron is a geometric construction of the integrand that incorporates these structures. This geometric construction further implies the amplitude is fully specified by constraining it to vanish on spurious residues. By writing the amplitude in a dlog basis, we provide nontrivial evidence that these analytic properties and “zero conditions” carry over into the nonplanar sector. Finally, this suggests that the concept of the amplituhedron can be extended to the nonplanar sector of N =more » 4 super-Yang-Mills theory.« less

  9. Nonplanarity and the protonation behavior of porphyrins

    SciTech Connect

    SOMMA,MARIA S.; MEDFORTH,CRAIG J.; TH,KEVIN M.; SHELNUTT,JOHN A.

    2000-03-21

    {sup 1}H NMR studies of the protonation of highly nonplanar porphyrins with strong acids reveal the presence of the previously elusive monocation, and show that its stability can be related to the amount of saddle distortion induced by protonation; the amount of saddle distortion for a porphyrin dication is also found to correlate well with the rate of intermolecular proton transfer.

  10. Nonplanar solitons collision in ultracold neutral plasmas

    SciTech Connect

    El-Tantawy, S. A.; Moslem, W. M.; El-Metwally, M.; Sabry, R.; El-Labany, S. K.; Schlickeiser, R.

    2013-09-15

    Collisions between two nonplanar ion-acoustic solitons in strongly coupled ultracold neutral plasmas composed of ion fluid and non-Maxwellian (nonthermal or superthermal) electron distributions are investigated. The extended Poincare-Lighthill-Kuo method is used to obtain coupled nonplanar Kortweg-de Vries equations for describing the system. The nonplanar phase shifts after the interaction of the two solitons are calculated. It is found that the properties of the nonplanar colliding solitons and its corresponding phase shifts are different from those in the planar case. The polarity of the colliding solitons strongly depends on the type of the non-Maxwellian electron distributions. A critical nonthermality parameter β{sub c} is identified. For values of β ≤ β{sub c} solitons with double polarity exist, while this behavior cannot occur for superthermal plasmas. The phase shift for nonthermal plasmas increases below β{sub c} for a positive soliton, but it decreases for β > β{sub c} for a negative soliton. For superthermal plasmas, the phase shift enhances rapidly for low values of spectral index κ and higher values of ions effective temperature ratio σ{sub *}. For 2 ≲ κ<10, the phase shift decreases but does not change for κ > 10. The nonlinear structure, as reported here, is useful for controlling the solitons created in forthcoming ultracold neutral plasma experiments.

  11. Massive nonplanar two-loop maximal unitarity

    NASA Astrophysics Data System (ADS)

    Søgaard, Mads; Zhang, Yang

    2014-12-01

    We explore maximal unitarity for nonplanar two-loop integrals with up to four massive external legs. In this framework, the amplitude is reduced to a basis of master integrals whose coefficients are extracted from maximal cuts. The hepta-cut of the nonplanar double box defines a nodal algebraic curve associated with a multiply pinched genus-3 Riemann surface. All possible configurations of external masses are covered by two distinct topological pictures in which the curve decomposes into either six or eight Riemann spheres. The procedure relies on consistency equations based on vanishing of integrals of total derivatives and Levi-Civita contractions. Our analysis indicates that these constraints are governed by the global structure of the maximal cut. Lastly, we present an algorithm for computing generalized cuts of massive integrals with higher powers of propagators based on the Bezoutian matrix method.

  12. Nonplanar Shock Waves in Dusty Plasmas

    NASA Astrophysics Data System (ADS)

    Mamun, A. A.; Shukla, P. K.

    2011-11-01

    Nonplanar (viz. cylindrical and spherical) electro-acoustic [dust-ion-acoustic (DIA) and dust-acoustic (DA)] shock waves have been investigated by employing the reductive perturbation method. The dust charge fluctuation (strong correlation among highly charged dust) is the source of dissipation, and is responsible for the formation of the DIA (DA) shock structures. The effects of cylindrical and spherical geometries on the time evolution of DIA and DA shock structures are examined and identified. The combined effects of vortex-like electron distribution and dust charge fluctuation (dust-correlation and effective dust-temperature) on the basic features of nonplanar DIA (DA) shock waves are pinpointed. The implications of our results in laboratory dusty plasma experiments are briefly discussed.

  13. Structural mechanisms of nonplanar hemes in proteins

    SciTech Connect

    Shelnutt, J.A.

    1997-05-01

    The objective is to assess the occurrence of nonplanar distortions of hemes and other tetrapyrroles in proteins and to determine the biological function of these distortions. Recently, these distortions were found by us to be conserved among proteins belonging to a functional class. Conservation of the conformation of the heme indicates a possible functional role. Researchers have suggested possible mechanisms by which heme distortions might influence biological properties; however, no heme distortion has yet been shown conclusively to participate in a structural mechanism of hemoprotein function. The specific aims of the proposed work are: (1) to characterize and quantify the distortions of the hemes in all of the more than 300 hemoprotein X-ray crystal structures in terms of displacements along the lowest-frequency normal coordinates, (2) to determine the structural features of the protein component that generate and control these nonplanar distortions by using spectroscopic studies and molecular-mechanics calculations for the native proteins, their mutants and heme-peptide fragments, and model porphyrins, (3) to determine spectroscopic markers for the various types of distortion, and, finally, (4) to discover the functional significance of the nonplanar distortions by correlating function with porphyrin conformation for proteins and model porphyrins.

  14. Nonplanarity through unitarity in the ABJM theory

    NASA Astrophysics Data System (ADS)

    Bianchi, Lorenzo; Bianchi, Marco S.

    2014-06-01

    We use unitarity techniques to compute the two-loop nonplanar corrections to the Sudakov form factor and the four-point amplitude in the ABJM theory. We start by reconstructing nonplanar integrals from two-particle cuts in three dimensions. This causes ambiguities due to the one-loop, four-point amplitude being subleading in dimensional regularization. We provide a prescription to circumvent them and show that it leads to the correct results, as checked against the recent Feynman diagram computation. For the amplitude, we point out an alternative basis of integrals, including a nonplanar double box with a numerator inspired by color-kinematics duality. We reproduce the result using a combination thereof with the coefficients fixed by generalized unitarity. For the BLG theory, we propose that this gives the form of the amplitude satisfying color-kinematics duality. Finally, we compute the complete two-loop amplitude of three-dimensional N =8 SYM and the corresponding four-point amplitude in N=16 supergravity as a double copy.

  15. A comparison of the binding of secretory component to immunoglobulin A (IgA) in human colostral S-IgA1 and S-IgA2.

    PubMed

    Almogren, Adel; Senior, Bernard W; Kerr, Michael A

    2007-02-01

    A detailed investigation of the binding of secretory component to immunoglobulin A (IgA) in human secretory IgA2 (S-IgA2) was made possible by the development of a new method of purifying S-IgA1, S-IgA2 and free secretory component from human colostrum using thiophilic gel chromatography and chromatography on Jacalin-agarose. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis of unreduced pure S-IgA2 revealed that, unlike in S-IgA1, a significant proportion of the secretory component was bound non-covalently in S-IgA2. When S-IgA1 was incubated with a protease purified from Proteus mirabilis the secretory component, but not the alpha-chain, was cleaved. This is in contrast to serum IgA1, in which the alpha-chain was cleaved under the same conditions - direct evidence that secretory component does protect the alpha-chain from proteolytic cleavage in S-IgA. Comparisons between the products of cleavage with P. mirabilis protease of free secretory component and bound secretory component in S-IgA1 and S-IgA2 also indicated that, contrary to the general assumption, the binding of secretory component to IgA is different in S-IgA2 from that in S-IgA1.

  16. Non-planar microfabricated gas chromatography column

    DOEpatents

    Lewis, Patrick R.; Wheeler, David R.

    2007-09-25

    A non-planar microfabricated gas chromatography column comprises a planar substrate having a plurality of through holes, a top lid and a bottom lid bonded to opposite surfaces of the planar substrate, and inlet and outlet ports for injection of a sample gas and elution of separated analytes. A plurality of such planar substrates can be aligned and stacked to provide a longer column length having a small footprint. Furthermore, two or more separate channels can enable multi-channel or multi-dimensional gas chromatography. The through holes preferably have a circular cross section and can be coated with a stationary phase material or packed with a porous packing material. Importantly, uniform stationary phase coatings can be obtained and band broadening can be minimized with the circular channels. A heating or cooling element can be disposed on at least one of the lids to enable temperature programming of the column.

  17. The Secretory Pathway Kinases

    PubMed Central

    Sreelatha, Anju; Kinch, Lisa N.; Tagliabracci, Vincent S.

    2015-01-01

    Protein phosphorylation is a nearly universal post-translation modification involved in a plethora of cellular events. Even though phosphorylation of extracellular proteins had been observed, the identity of the kinases that phosphorylate secreted proteins remained a mystery until recently. Advances in genome sequencing and genetic studies have paved the way for the discovery of a new class of kinases that localize within the endoplasmic reticulum, Golgi apparatus and the extracellular space. These novel kinases phosphorylate proteins and proteoglycans in the secretory pathway and appear to regulate various extracellular processes. Mutations in these kinases cause human disease, thus underscoring the biological importance of phosphorylation within the secretory pathway. PMID:25862977

  18. Discrete differential geometry: the nonplanar quadrilateral mesh.

    PubMed

    Twining, Carole J; Marsland, Stephen

    2012-06-01

    We consider the problem of constructing a discrete differential geometry defined on nonplanar quadrilateral meshes. Physical models on discrete nonflat spaces are of inherent interest, as well as being used in applications such as computation for electromagnetism, fluid mechanics, and image analysis. However, the majority of analysis has focused on triangulated meshes. We consider two approaches: discretizing the tensor calculus, and a discrete mesh version of differential forms. While these two approaches are equivalent in the continuum, we show that this is not true in the discrete case. Nevertheless, we show that it is possible to construct mesh versions of the Levi-Civita connection (and hence the tensorial covariant derivative and the associated covariant exterior derivative), the torsion, and the curvature. We show how discrete analogs of the usual vector integral theorems are constructed in such a way that the appropriate conservation laws hold exactly on the mesh, rather than only as approximations to the continuum limit. We demonstrate the success of our method by constructing a mesh version of classical electromagnetism and discuss how our formalism could be used to deal with other physical models, such as fluids.

  19. Mammary Analogue Secretory Carcinoma.

    PubMed

    Stevens, Todd M; Parekh, Vishwas

    2016-09-01

    Mammary analogue secretory carcinoma (MASC) is a recently described salivary gland tumor that shares the same histologic appearance and ETV6 gene (12p13) rearrangement as secretory carcinoma of the breast. Prior to its recognition, MASC cases were commonly labeled acinic cell carcinoma and adenocarcinoma, not otherwise specified. Despite distinctive histologic features, MASC may be difficult to distinguish from other salivary gland tumors, in particular zymogen-poor acinic cell carcinoma and low-grade salivary duct carcinoma. Although characteristic morphologic and immunohistochemical features form the basis of a diagnosis of MASC, the presence of an ETV6-NTRK3 gene fusion is confirmatory. Given its recent recognition the true prognostic import of MASC is not yet clearly defined. PMID:27575269

  20. Nonlinear waves in nonplanar and nonuniform dusty plasmas

    SciTech Connect

    Xue Jukui; Zhang Liping

    2006-02-15

    The nonlinear properties of the dust acoustic solitary wave and shock wave in inhomogeneous nonplanar dusty plasmas are considered theoretically and numerically. The effects of nonthermally distributed ions, nonadiabatic dust charge fluctuation, and the inhomogeneity caused by nonuniform equilibrium particle density, nonuniform equilibrium charging, and nonplanar geometry on waves are presented. When {tau}{sub ch}/{tau}{sub d} is small but finite, where {tau}{sub ch} is the charging time scale and {tau}{sub d} is the hydrodynamical time scale, a variable coefficients nonplanar Korteweg-de Vries (KdV) Burgers equation governing the nonlinear waves is derived by the perturbation method. The analytical expressions for the evolution of soliton and shock wave (both oscillatory and monotone shock) are obtained and the theoretical results are confirmed by the numerical solution of the nonlinear wave equation.

  1. Experimental investigation of non-planar sheared outboard wing planforms

    NASA Technical Reports Server (NTRS)

    Naik, D. A.; Ostowari, C.

    1988-01-01

    The outboard planforms of wings have been found to be of prime importance in studies of induced drag reduction. This conclusion is based on an experimental and theoretical study of the aerodynamic characteristics of planar and nonplanar outboard wing forms. Six different configurations; baseline rectangular, planar sheared, sheared with dihedral, sheared with anhedral, rising arc, and drooping arc were investigated for two different spans. Span efficiencies as much as 20 percent greater than baseline can be realized with nonplanar wing forms. Optimization studies show that this advantage can be achieved along with a bending moment benefit. Parasite drag and lateral stability estimations were not included in the analysis.

  2. Absorption and Ablation for Non-Planar Geometries

    NASA Astrophysics Data System (ADS)

    Oh, Benjamin; Sinko, John

    2011-04-01

    The Bouguer-Lambert-Beer absorption law is a critical component of analytical laser ablation models. This law has been found to be useful for planar applications but it can also have significance in non-planar geometries. To be accurate, these applications must take into consideration the precise physical setup. Certain geometries offer special properties that may be beneficial to laser propulsion methods, specifically those of uniform ablation using focusing nozzles. This paper investigates the special circumstances using modified forms of the absorption law that apply to the considered parabolic, conical and spherical non-planar geometries.

  3. Constrained Quantum Mechanics: Chaos in Non-Planar Billiards

    ERIC Educational Resources Information Center

    Salazar, R.; Tellez, G.

    2012-01-01

    We illustrate some of the techniques to identify chaos signatures at the quantum level using as guiding examples some systems where a particle is constrained to move on a radial symmetric, but non-planar, surface. In particular, two systems are studied: the case of a cone with an arbitrary contour or "dunce hat billiard" and the rectangular…

  4. Immunological studies of IgA nephropathy in blacks reveal elevations of serum IgA2 as well as IgA1.

    PubMed

    Crowley-Nowick, P A; Bull, R; van den Wall Bake, A W; Kulhavy, L; Julian, B A; Jackson, S

    1994-01-01

    Although IgA nephropathy (IgAN) is recognized worldwide as the most common primary glomerulonephritis, the prevalence of this disease among American blacks is strikingly low despite the frequency of other renal disorders. We have previously described the clinical features of 27 black patients enrolled in a multicentre IgAN database; in this paper we report several immunological parameters of the disease in this population. Quantification of serum immunoglobulins revealed significantly higher concentrations of total IgA, IgA1 and IgA2 (P = 0.0001, 0.002 and 0.005 respectively) in the patients, but no significant increases in IgG or IgM. Examination of immunoglobulin synthesis by peripheral blood lymphocytes indicated relatively few differences in the secretion of immunoglobulins by patients compared to healthy American blacks. The spontaneous production of total IgA, IgA1, and IgA2 in patients was depressed compared to the control subjects (P = 0.02, 0.04, 0.03,), yet the ratio of IgA1:IgA2 was normal. Stimulation with pokeweed mitogen enhanced secretion of immunoglobulin in both subject groups. However, a significantly greater IgA1:IgA2 ratio was noted in the patients (P = 0.002). Circulating immune complexes containing C3 and IgA as well as C3 and IgM were elevated in the patients (P = 0.0006, 0.0003 and 0.02, respectively). These immunological aberrancies did not correlate with clinical manifestations of disease. These data suggest the immune abnormalities of black IgAN patients are similar to, but not identical with, those of white patients.

  5. Subclasses IgA1 and IgA2 in serum and synovial fluid in rheumatoid arthritis and reactive synovitis of local origin.

    PubMed Central

    Hrncír, Z; Tichý, M

    1978-01-01

    Subclasses IgA1 and IgA2 in serum were examined in 40 patients (28 cases of rheumatoid arthritis and 12 cases of reactive synovitis of local origin) and also in synovial fluid of the knee joint in 17 of these patients. The levels of IgA1 and IgA2 in serum were statistically significantly higher than in synovial fluid in both groups of patients (P = 0.0237--0.0018), but significant correlations between serum and synovial fluid for IgA1 (R = 0.8855, P = 0.0010) and for IgA2 (r = 0.7630, P = 0.0124) were found only in cases of rheumatoid arthritis. A percentage evaluation revealed a significant disproportion (P = 0.0028) in favour of IgA1 in synovial fluid during rheumatoid arthritis. The analysis of proportions of IgA subclasses and rheumatoid factor has shown no significant relationships. PMID:749696

  6. Highly conformal fabrication of nanopatterns on non-planar surfaces

    NASA Astrophysics Data System (ADS)

    Massiot, Inès; Trompoukis, Christos; Lodewijks, Kristof; Depauw, Valérie; Dmitriev, Alexandre

    2016-06-01

    While the number of techniques for patterning materials at the nanoscale exponentially increases, only a handful of methods approach the conformal patterning of strongly non-planar surfaces. Here, using the direct surface self-assembly of colloids by electrostatics, we produce highly conformal bottom-up nanopatterns with a short-range order. We illustrate the potential of this approach by devising functional nanopatterns on highly non-planar substrates such as pyramid-textured silicon substrates and inherently rough polycrystalline films. We further produce functionalized polycrystalline thin-film silicon solar cells with enhanced optical performance. The perspective presented here to pattern essentially any surface at the nanoscale, in particular surfaces with high inherent roughness or with microscale features, opens new possibilities in a wide range of advanced technologies from affordable photovoltaics and optoelectronics to cellular engineering.

  7. Application of Random Ferns for non-planar object detection

    NASA Astrophysics Data System (ADS)

    Mastov, Alexey; Konovalenko, Ivan; Grigoryev, Anton

    2015-12-01

    The real time object detection task is considered as a part of a project devoted to development of autonomous ground robot. This problem has been successfully solved with Random Ferns algorithm, which belongs to keypoint-based method and uses fast machine learning algorithms for keypoint matching step. As objects in the real world are not always planar, in this article we describe experiments of applying this algorithm for non-planar objects. Also we introduce a method for fast detection of a special class of non-planar objects | those which can be decomposed into planar parts (e.g. faces of a box). This decomposition needs one detector for each side, which may significantly affect speed of detection. Proposed approach copes with it by omitting repeated steps for each detector and organizing special queue of detectors. It makes the algorithm three times faster than naive one.

  8. Dynamics of rotationally fissioned asteroids: non-planar case

    NASA Astrophysics Data System (ADS)

    Boldrin, L. A. G.; Scheeres, D. J.; Winter, O. C.

    2016-10-01

    The rotational fission of asteroids has been studied previously with simplified models restricted to planar motion. However, the observed physical configuration of contact binaries leads one to conclude that most of them are not in a planar configuration and hence would not be restricted to planar motion once they undergo rotational fission. This motivated a study of the evolution of initially non-planar binaries created by fission. Using a two-ellipsoid model, we performed simulations taking only gravitational interactions between components into account. We simulate 91 different initial inclinations of the equator of the secondary body for 19 different mass ratios. After disruption, the binary system dynamics are chaotic, as predicted from theory. Starting the system in a non-planar configuration leads to a larger energy and enhanced coupling between the rotation state of the smaller fissioned body and the evolving orbital system, and enables re-impact to occur. This leads to differences with previous planar studies, with collisions and secondary spin fission occurring for all mass ratios with inclinations θ0 ≥ 40o, and mimics a Lidov-Kozai mechanism. Out of 1729 studied cases, we found that ˜14 per cent result in secondary fission, ˜25 per cent result in collisions and ˜6 per cent have lifetimes longer than 200 yr. In Jacobson & Scheeres stable binaries only formed in cases with mass ratios q < 0.20. Our results indicate that it should be possible to obtain a stable binary with the same mechanisms for cases with mass ratios larger than this limit, but that the system should start in a non-planar configuration.

  9. Spin Vortex Resonance in Non-planar Ferromagnetic Dots

    PubMed Central

    Ding, Junjia; Lapa, Pavel; Jain, Shikha; Khaire, Trupti; Lendinez, Sergi; Zhang, Wei; Jungfleisch, Matthias B.; Posada, Christian M.; Yefremenko, Volodymyr G.; Pearson, John E.; Hoffmann, Axel; Novosad, Valentine

    2016-01-01

    In planar structures, the vortex resonance frequency changes little as a function of an in-plane magnetic field as long as the vortex state persists. Altering the topography of the element leads to a vastly different dynamic response that arises due to the local vortex core confinement effect. In this work, we studied the magnetic excitations in non-planar ferromagnetic dots using a broadband microwave spectroscopy technique. Two distinct regimes of vortex gyration were detected depending on the vortex core position. The experimental results are in qualitative agreement with micromagnetic simulations. PMID:27143405

  10. Tunneling properties of nonplanar molecules in a gas medium

    SciTech Connect

    Bahrami, Mohammad; Bassi, Angelo

    2011-12-15

    We propose a simple, general, and accurate formula for analyzing the tunneling between classical configurations of a nonplanar molecule in a gas medium, as a function of the thermodynamic parameters of the gas. We apply it to two interesting cases: (i) the shift to zero frequency of the inversion line of ammonia, upon an increase in the pressure of the gas; and (ii) the destruction of the coherent tunneling of D{sub 2}S{sub 2} molecules in a He gas. In both cases, we compare our analysis with previous theoretical and experimental results.

  11. A biosynthetic regulated secretory pathway in constitutive secretory cells

    PubMed Central

    1996-01-01

    It has frequently been proposed that while the constitutive secretory pathway is present in all cells, the regulated secretory pathway is found only in specialized cells such as neuronal, endocrine, or exocrine types. In this study we provide evidence that suggests that this distinction is not as restrictive as proposed. We have identified a population of post-Golgi storage vesicles in several constitutive secretory cells using [35S]SO4-labeled glycosaminoglycan (GAG) chains as a marker. A fraction of this pool of vesicles can undergo exocytosis in response to stimuli such as cytoplasmic Ca2+ and phorbol esters. The effect of Ca2+ was demonstrated both in intact cells in the presence of the ionophore A23187 and in streptolysin-O-permeabilized semi-intact cells. N-ethylmaleiimide, under conditions known to block regulated and constitutive secretion, inhibited the stimulated secretion from these cells, suggesting that the observed release of labeled GAG chains was not due to a leakage artefact. Subcellular fractionation revealed that the stored GAG chains were in low-density membrane granules (d approximately 1.12 g/ml), whose size was greater than that of synaptic- like vesicles found in PC12 cells. In addition, in CHO cells that express epitope-tagged rab 3D, the labeled GAG chains were found to cofractionate with the exogenous rab protein. When expressed in the regulated cell line AtT-20, this tagged rab protein was found to colocalize with ACTH-containing dense-core granules by indirect immunofluorescence. Taken together, these results provide evidence for the presence of a cryptic regulated secretory pathway in "constitutive" cells and suggest that the regulated secretory pathway is more widespread amongst different cell types than previously believed. PMID:8682857

  12. Proteolysis in the secretory pathway

    SciTech Connect

    Guzowski, D.E.; Bienkowski, R.S.

    1987-05-01

    Many secretory proteins are degraded intracellularly rather than secreted, however the location of this catabolic process is not known. The authors have tested the hypothesis that the degradation occurs in the organelles of the secretory pathway. Slices of rat liver were incubated with (/sup 14/C)leucine for 3 h and then incubated under chase conditions for 30 min. The tissue was homogenized and the Golgi apparatus, smooth endoplasmic reticulum (sER) and rough endoplasmic reticulum (rER) were isolated by ultracentrifugation on a discontinuous sucrose gradient. The organelles were incubated in 0.3M sucrose-50 mM citrate (pH 4) for 8-12 h at 37 C; control samples were incubated at 4 C. Percent degradation was calculated as the amount of acid soluble radioactivity released relative to total radioactivity in the sample. Proteolysis in the organelles incubated at 37 C was as follows: Golgi: 15-25%; sER: 10-20%; rER: 10-20%. Proteolysis at 4 C was negligible in all cases. These results support the hypothesis that the compartments of the secretory pathway are capable of degrading newly synthesized secretory proteins.

  13. Probabilistic Prognosis of Non-Planar Fatigue Crack Growth

    NASA Technical Reports Server (NTRS)

    Leser, Patrick E.; Newman, John A.; Warner, James E.; Leser, William P.; Hochhalter, Jacob D.; Yuan, Fuh-Gwo

    2016-01-01

    Quantifying the uncertainty in model parameters for the purpose of damage prognosis can be accomplished utilizing Bayesian inference and damage diagnosis data from sources such as non-destructive evaluation or structural health monitoring. The number of samples required to solve the Bayesian inverse problem through common sampling techniques (e.g., Markov chain Monte Carlo) renders high-fidelity finite element-based damage growth models unusable due to prohibitive computation times. However, these types of models are often the only option when attempting to model complex damage growth in real-world structures. Here, a recently developed high-fidelity crack growth model is used which, when compared to finite element-based modeling, has demonstrated reductions in computation times of three orders of magnitude through the use of surrogate models and machine learning. The model is flexible in that only the expensive computation of the crack driving forces is replaced by the surrogate models, leaving the remaining parameters accessible for uncertainty quantification. A probabilistic prognosis framework incorporating this model is developed and demonstrated for non-planar crack growth in a modified, edge-notched, aluminum tensile specimen. Predictions of remaining useful life are made over time for five updates of the damage diagnosis data, and prognostic metrics are utilized to evaluate the performance of the prognostic framework. Challenges specific to the probabilistic prognosis of non-planar fatigue crack growth are highlighted and discussed in the context of the experimental results.

  14. Recombinant human IgA1 and IgA2 autoantibodies to type VII collagen induce subepidermal blistering ex vivo.

    PubMed

    Recke, Andreas; Trog, Luisa M; Pas, Hendri H; Vorobyev, Artem; Abadpour, Aida; Jonkman, Marcel F; van Zandbergen, Ger; Kauderer, Claudia; Zillikens, Detlef; Vidarsson, Gestur; Ludwig, Ralf J

    2014-08-15

    Subepidermal autoimmune blistering dermatoses (AIBD) are prototypic autoantibody-mediated diseases. In epidermolysis bullosa acquisita (EBA), an autoimmune disease with severe and chronic skin blistering, autoantibodies are directed against type VII collagen. IgG is the predominant autoantibody isotype of EBA, the pathogenicity of which has been demonstrated in a variety of in vivo and ex vivo disease models. In contrast, there is not much evidence for the pathogenicity of IgA, which may appear as the only autoantibody isotype in some EBA patients. To investigate the pathogenic potential of IgA autoantibodies, we generated chimeric V gene-matched human IgA1, IgA2, and control IgG1 autoantibodies directed against type VII collagen. Immobilized immune complexes containing the rIgA1 and rIgA2 autoantibodies induced the dose-dependent release of reactive oxygen species from neutrophil granulocytes, a precondition for blister formation. Moreover, both rIgA1 and rIgA2 induced leukocyte-dependent dermal-epidermal separation in cryosections of human skin. In contrast with rIgG1, neither rIgA1 nor rIgA2 was capable of inducing complement deposition at the dermal-epidermal junction. Because complement activation is a prerequisite for blister induction, this lack of function compared with IgG1 may be compensated for by the stronger activation of neutrophil granulocytes by both IgA1 and IgA2. For IgG-mediated AIBD, immunoadsorption therapy is a convenient treatment modality for the removal of pathogenic autoantibodies, particularly in treatment-resistant cases. The results of this study show the pathogenic potential of IgA autoantibodies and support the development of adsorber matrices for IgA-mediated AIBD.

  15. Differences in N-glycan structures found on recombinant IgA1 and IgA2 produced in murine myeloma and CHO cell lines.

    PubMed

    Yoo, Esther M; Yu, Li J; Wims, Letitia A; Goldberg, David; Morrison, Sherie L

    2010-01-01

    The development and production of recombinant monoclonal antibodies is well established. Although most of these are IgGs, there is also great interest in producing recombinant IgAs since this isotype plays a critical role in providing immunologic protection at mucosal surfaces. The choice of expression system for production of recombinant antibodies is crucial because they are glycoproteins containing at least one N-linked carbohydrate. These glycans have been shown to contribute to the stability, pharmacokinetics and biologic function of antibodies. We have produced recombinant human IgA1 and all three allotypes of IgA2 in murine myeloma and CHO cell lines to systematically characterize and compare the N-linked glycans. Recombinant IgAs produced in murine myelomas differ significantly from IgA found in humans in that they contain the highly immunogenic Galalpha(1,3)Gal epitope and N-glycolylneuraminic acid residues, indicating that murine myeloma is not the optimal expression system for the production of human IgA. In contrast, IgAs produced in CHO cells contained glycans that were more similar to those found on human IgA. Expression of IgA1 and IgA2 in Lec2 and Lec8 cell lines that are defective in glycan processing resulted in a less complex pool of N-glycans. In addition, the level of sialylation of rIgAs produced in murine and CHO cells was significantly lower than that previously reported for serum IgA1. These data underscore the importance of choosing the appropriate cell line for the production of glycoproteins with therapeutic potential.

  16. Differences in N-glycan structures foundon recombinant IgA1 and IgA2 producedin murine myeloma and CHO cell lines

    PubMed Central

    Yu, Li J; Wims, Letitia A; Goldberg, David; Morrison, Sherie L

    2010-01-01

    The development and production of recombinant monoclonal antibodies is well established. Although most of these are IgGs, there is also great interest in producing recombinant IgAs since this isotype plays a critical role in providing immunologic protection at mucosal surfaces. the choice of expression system for production of recombinant antibodies is crucial because they are glycoproteins containing at least one N-linked carbohydrate. these glycans have been shown to contribute to the stability, pharmacokinetics and biologic function of antibodies. We have produced recombinant human IgA1 and all three allotypes of IgA2 in murine myeloma and CHo cell lines to systematically characterize and compare the N-linked glycans. Recombinant IgAs produced in murine myelomas differ significantly from IgA found in humans in that they contain the highly immunogenic Galα(1,3)Gal epitope and N-glycolylneuraminic acid residues, indicating that murine myeloma is not the optimal expression system for the production of human IgA. In contrast, IgAs produced in CHo cells contained glycans that were more similar to those found on human IgA. expression of IgA1 and IgA2 in Lec2 and Lec8 cell lines that are defective in glycan processing resulted in a less complex pool of N-glycans. In addition, the level of sialylation of rIgAs produced in murine and CHo cells was significantly lower than that previously reported for serum IgA1. these data underscore the importance of choosing the appropriate cell line for the production of glycoproteins with therapeutic potential. PMID:20431350

  17. Strain and the optoelectronic properties of nonplanar phosphorene monolayers

    PubMed Central

    Mehboudi, Mehrshad; Utt, Kainen; Terrones, Humberto; Harriss, Edmund O.; Pacheco SanJuan, Alejandro A.; Barraza-Lopez, Salvador

    2015-01-01

    Lattice kirigami, ultralight metamaterials, polydisperse aggregates, ceramic nanolattices, and 2D atomic materials share an inherent structural discreteness, and their material properties evolve with their shape. To exemplify the intimate relation among material properties and the local geometry, we explore the properties of phosphorene––a new 2D atomic material––in a conical structure, and document a decrease of the semiconducting gap that is directly linked to its nonplanar shape. This geometrical effect occurs regardless of phosphorene allotrope considered, and it provides a unique optical vehicle to single out local structural defects on this 2D material. We also classify other 2D atomic materials in terms of their crystalline unit cells, and propose means to obtain the local geometry directly from their diverse 2D structures while bypassing common descriptions of shape that are based from a parametric continuum. PMID:25918413

  18. Strain and the optoelectronic properties of nonplanar phosphorene monolayers.

    PubMed

    Mehboudi, Mehrshad; Utt, Kainen; Terrones, Humberto; Harriss, Edmund O; Pacheco SanJuan, Alejandro A; Barraza-Lopez, Salvador

    2015-05-12

    Lattice kirigami, ultralight metamaterials, polydisperse aggregates, ceramic nanolattices, and 2D atomic materials share an inherent structural discreteness, and their material properties evolve with their shape. To exemplify the intimate relation among material properties and the local geometry, we explore the properties of phosphorene--a new 2D atomic material--in a conical structure, and document a decrease of the semiconducting gap that is directly linked to its nonplanar shape. This geometrical effect occurs regardless of phosphorene allotrope considered, and it provides a unique optical vehicle to single out local structural defects on this 2D material. We also classify other 2D atomic materials in terms of their crystalline unit cells, and propose means to obtain the local geometry directly from their diverse 2D structures while bypassing common descriptions of shape that are based from a parametric continuum.

  19. Cell projection of meshes with non-planar faces

    SciTech Connect

    Max, N; Williams, P; Silva, C

    2000-11-27

    Volume rendering converts a scalar function on a 3D volume into varying colors and opacities, and creates an image by integrating the color and opacity effects along viewing rays through each pixel [1]. For data specified on a regular grid, the ray tracing is straightforward [2,3,4,5], and similar effects can be obtained with 3D textures [6]. For curvilinear or irregular grids, these methods are only applicable after the data has been resampled. An alternative, which works directly on these more general grids, is cell projection [7,8,9]. The cells composited onto the image in back to front sorted order. The projections of the edges of a single cell divide the image plane into polygons, which can be scan converted and composited by standard graphics hardware. In references [9,10,11], we assumed that the cells were polyhedra with planar faces. A curvilinear grid maps a rectangular grid onto a curved volume, for example to fit next to an airplane wing or ship hull, and quadrilateral faces may map to non-planar surfaces. Irregular grids are fitted to complex geometries, for example mechanical parts, and even initially flat faces may become non-planar as the grid elements deform, for example, in a car crash simulation. Non-planar faces cause problems in the sorting and compositing when a viewing ray crosses the same face twice. We call such a face a ''problem face''. For example, the ray may leave cell A through face F, enter cell B , and then enter cell A again through the same face F. If a viewing ray intersects a cell like A in two disjoint segments, we call the cell a ''problem cell''. This makes it impossible to sort cells A and B in back-to-front compositing order. Our solution is to divide problem cells into tetrahedra, which have planar faces. A single hexahedron can be projected and composited more quickly than the five or six tetrahedra into which it is subdivided, so we subdivide only the problem cells. In the example above, cell B might not turn out to be a

  20. Characterization of a secretory proteinase of Candida parapsilosis and evidence for the absence of the enzyme during infection in vitro.

    PubMed Central

    Rüchel, R; Böning, B; Borg, M

    1986-01-01

    The opportunistic yeastlike fungi of the genus Candida comprise three species which are proteolytic in vitro. Among them, C. albicans and C. tropicalis are of foremost medical importance. However, a strict correlation between extracellular proteolytic activity and virulence is opposed by the low virulence of the third proteolytic species, C. parapsilosis. We purified the secretory acid proteinase of C. parapsilosis (clinical isolate 265). The enzyme is a carboxyl proteinase (EC 3.4.23) like all other secretory Candida proteinases handled so far. Proteinase 265 is distinguished by a lower molecular weight (approximately 33,000); it has increased hydrophobicity, which accounts for inhibition of the enzyme by hemin, and required the presence of nonionic detergent in the initial steps of purification. The enzyme already undergoes alkaline denaturation at neutrality. Its activity is thus confined to the acid microenvironment of the fungal cell wall. Within this range, the enzyme may degrade immunoglobulins like immunoglobulin A1 (IgA1), IgA2, and secretory IgA. No indication was found for glycosylation of proteinase 265 and the related enzyme of C. albicans CBS 2730. However, the comparable proteinase of C. tropicalis 293 was identified as a manno protein. Antiserum against proteinase 265 cross-reacted strongly with corresponding enzymes from other Candida species. Antisera against proteinases of C. albicans and C. tropicalis reacted only weakly with proteinase 265. Thus, secretory Candida proteinases are likely to possess common and species-specific antigenic sites. In contrast to C. albicans, infection of phagocytes by C. parapsilosis 265 was not accompanied by secretion of fungal proteinase. This lack of induction of the enzyme under conditions of infection may account for the low virulence of most isolates of C. parapsilosis. Images PMID:3525413

  1. Secretory breast cancer. Case report

    PubMed Central

    LOMBARDI, A.; MAGGI, S.; BERSIGOTTI, L.; LAZZARIN, G.; NUCCETELLI, E.; AMANTI, C.

    2013-01-01

    Summary: Secretory carcinoma of the breast is a rare tumor initially described in children but occurring equally in adult population. This unusual breast cancer subtype has a generally favorable prognosis, although several cases have been described in adults with increased aggressiveness and a risk of metastases. However, surgery is still considered the most appropriate treatment for this pathology. We describe the case of a 50 – year-old woman who has undergone a breast conservative surgery for a little tumor, preoperatively diagnosticated by a fine needle aspiration biopsy (FNAB) as a well differentiated infiltrating carcinoma. PMID:23660165

  2. Secretory breast cancer. Case report.

    PubMed

    Lombardi, A; Maggi, S; Bersigotti, L; Lazzarin, G; Nuccetelli, E; Amanti, C

    2013-04-01

    Secretory carcinoma of the breast is a rare tumor initially described in children but occurring equally in adult population. This unusual breast cancer subtype has a generally favorable prognosis, although several cases have been described in adults with increased aggressiveness and a risk of metastases. However, surgery is still considered the most appropriate treatment for this pathology. We describe the case of a 50 -year-old woman who has undergone a breast conservative surgery for a little tumor, preoperatively diagnosticated by a fine needle aspiration biopsy (FNAB) as a well differentiated infiltrating carcinoma.

  3. Hybrid orbital deformation (HOD) effect and spectral red-shift property of nonplanar porphyrin.

    PubMed

    Zhou, Zaichun; Cao, Chenzhong; Liu, Qiuhua; Jiang, Rongqing

    2010-04-16

    A series of 5,15-meso,meso-strapped nonplanar porphyrins with different degrees of ruffling distortion, as a model system, have been synthesized and characterized. The spectral red-shift of the nonplanar porphyrins was experimentally demonstrated to mainly originate from the hybrid orbital deformation (HOD) effect due to the distortion in the tetrapyrrole macrocycle, which confirmed previous explanations to the red-shift phenomenon.

  4. Method for brazing together planar and nonplanar metal members

    DOEpatents

    Hammersand, Fred G.; Witkowski, Anthony J.

    1985-01-01

    The invention relates to a method and apparatus for brazing two metal members together, at least one of which is nonplanar, in a brazing furnace using a substantially pure brazing material. The method comprises the steps of utilizing a brazing fixture to hold the two metal members in tangential relation to one another along a portion of each member so that a cavity is formed adjacent to the contacting portions. A braze material is then positioned within the cavity. The braze fixture, the metal members, and the braze material are then placed in a brazing furnace. A heat shield is then placed over the braze fixture, the metal members, and the braze material to shield the braze material from direct furnace radiation. The furnace temperature is linearly increased at a rate of about 180.degree. C. per hour until a temperature of 350.degree. C. is achieved. Heat is transferred by conduction from the metal members to the braze material to cause the braze material to melt. Some material from the metal members slowly diffuses into the braze material forming a braze joint. The furnace is rapidly cooled to room temperature using nitrogen gas. The brazed assemblies made according to this method are superior to assemblies formed by heliarc welding.

  5. Adsorption Behavior of Nonplanar Phthalocyanines: Competition of Different Adsorption Conformations

    PubMed Central

    2016-01-01

    Using density functional theory augmented with state-of-the-art van der Waals corrections, we studied the geometric and electronic properties of nonplanar chlorogallium-phthalocyanine GaClPc molecules adsorbed on Cu(111). Comparing these results with published experimental data for adsorption heights, we found indications for breaking of the metal–halogen bond when the molecule is heated during or after the deposition process. Interestingly, the work-function change induced by this dissociated geometry is the same as that computed for an intact adsorbate layer in the “Cl-down” configuration, with both agreeing well with the experimental photoemission data. This is unexpected, as the chemical natures of the adsorbates and the adsorption distances are markedly different in the two cases. The observation is explained as a consequence of Fermi-level pinning due to fractional charge transfer at the interface. Our results show that rationalizing the adsorption configurations on the basis of electronic interface properties alone can be ambiguous and that additional insight from dispersion-corrected DFT simulations is desirable. PMID:27066160

  6. Assumptions and ambiguities in nonplanar acoustic soliton theory

    SciTech Connect

    Verheest, Frank; Hellberg, Manfred A.

    2014-02-15

    There have been many recent theoretical investigations of the nonlinear evolution of electrostatic modes with cylindrical or spherical symmetry. Through a reductive perturbation analysis based on a quasiplanar stretching, a modified form of the Korteweg-de Vries or related equation is derived, containing an additional term which is linear in the electrostatic potential and singular at time t = 0. Unfortunately, these analyses contain several restrictive assumptions and ambiguities which are normally neither properly explained nor discussed, and severely limit the applicability of the technique. Most glaring are the use of plane-wave stretchings, the assumption that shape-preserving cylindrical modes can exist and that, although time is homogeneous, the origin of time (which can be chosen arbitrarily) needs to be avoided. Hence, only in the domain where the nonlinear modes are quasiplanar, far from the axis of cylindrical or from the origin of spherical symmetry can acceptable but unexciting results be obtained. Nonplanar nonlinear modes are clearly an interesting topic of research, as some of these phenomena have been observed in experiments. However, it is argued that a proper study of such modes needs numerical simulations rather than ill-suited analytical approximations.

  7. Acceleration in a nonplanar time-dependent billiard

    NASA Astrophysics Data System (ADS)

    Raeisi, Sedighe; Eslami, Parvin

    2016-08-01

    We study the dynamical properties of a particle in a nonplanar square billiard. The plane of the billiard has a sinusoidal shape. We consider both the static and time-dependent plane. We study the affect of different parameters that control the geometry of the billiard in this model. We consider variations of different parameters of the model and describe how the particle trajectory is affected by these parameters. We also investigate the dynamical behavior of the system in the static condition using its reduced phase plot and show that the dynamics of the particle inside the billiard may be regular, mixed, or chaotic. Finally, the problem of the particle energy growth is studied in the billiard with the time-dependent plane. We show that when in the static case, the billiard is chaotic, then the particle energy in the time-dependent billiard grows for a small number of collisions, and then it starts to saturate. But when the dynamics of the static case is regular, then the particle average energy in the time-dependent situation stays constant.

  8. Acceleration in a nonplanar time-dependent billiard.

    PubMed

    Raeisi, Sedighe; Eslami, Parvin

    2016-08-01

    We study the dynamical properties of a particle in a nonplanar square billiard. The plane of the billiard has a sinusoidal shape. We consider both the static and time-dependent plane. We study the affect of different parameters that control the geometry of the billiard in this model. We consider variations of different parameters of the model and describe how the particle trajectory is affected by these parameters. We also investigate the dynamical behavior of the system in the static condition using its reduced phase plot and show that the dynamics of the particle inside the billiard may be regular, mixed, or chaotic. Finally, the problem of the particle energy growth is studied in the billiard with the time-dependent plane. We show that when in the static case, the billiard is chaotic, then the particle energy in the time-dependent billiard grows for a small number of collisions, and then it starts to saturate. But when the dynamics of the static case is regular, then the particle average energy in the time-dependent situation stays constant. PMID:27627308

  9. Cloning and structural analysis of two highly divergent IgA isotypes, IgA1 and IgA2 from the duck billed platypus, Ornithorhynchus anatinus.

    PubMed

    Vernersson, M; Belov, K; Aveskogh, M; Hellman, L

    2010-01-01

    To trace the emergence of modern IgA isotypes during vertebrate evolution we have studied the immunoglobulin repertoire of a model monotreme, the platypus. Two highly divergent IgA-like isotypes (IgA1 and IgA2) were identified and their primary structures were determined from full-length cDNAs. A comparative analysis of the amino acid sequences for IgA from various animal species showed that the two platypus IgA isotypes form a branch clearly separated from their eutherian (placental) counterparts. However, they still conform to the general structure of eutherian IgA, with a hinge region and three constant domains. This indicates that the deletion of the second domain and the formation of a hinge region in IgA did occur very early during mammalian evolution, more than 166 million years ago. The two IgA isotypes in platypus differ in primary structure and appear to have arisen from a very early gene duplication, possibly preceding the metatherian eutherian split. Interestingly, one of these isotypes, IgA1, appears to be expressed in only the platypus, but is present in the echidna based on Southern blot analysis. The platypus may require a more effective mucosal immunity, with two highly divergent IgA forms, than the terrestrial echidna, due to its lifestyle, where it is exposed to pathogens both on land and in the water. PMID:19913303

  10. Origin of the nonplanarity of tetrafluoro cyclobutadiene, C4F4.

    PubMed

    Seal, Prasenjit; Chakrabarti, Swapan

    2007-02-01

    Density functional theory as well as Møller-Plesset investigations has been carried out on tetrafluoro cyclobutadiene, C4F4, to explore the origin of its nonplanarity. Although Petersson et al. (Petersson, E. J.; Fanuele, J. C.; Nimlos, M. R.; Lemal, D. M.; Ellison, G. B.; Radziszewski, J. G. J. Am. Chem. Soc. 1997, 119, 11122-11123) had earlier predicted a nonplanar geometry of this compound on the basis of spectral and bond orbital analysis, the explanation of the same from a more fundamental point of view is still missing. In the present study, we provide a heuristic explanation for the origin of nonplanarity of C4F4. The two major driving forces behind this nonplanar geometry are the unusual aromaticity of this cyclic homoatomic 4pi electron system and the second-order Jahn-Teller effect (SOJTE). These driving forces can well be explained by various energy and density parameters and also by nucleus-independent chemical shift (NICS) values. Aromaticity of a cyclic homoatomic 4pi electron system is quite remarkable. The enhancement of pi- delocalization as evidenced from molecular orbital analysis may be attributed to s-ppi mixing in nonplanar C4F4.

  11. Secretory diarrhoea: mechanisms and emerging therapies

    PubMed Central

    Thiagarajah, Jay R.; Donowitz, Mark; Verkman, Alan S.

    2016-01-01

    Diarrhoeal disease remains a major health burden worldwide. Secretory diarrhoeas are caused by certain bacterial and viral infections, inflammatory processes, drugs and genetic disorders. Fluid secretion across the intestinal epithelium in secretory diarrhoeas involves multiple ion and solute transporters, as well as activation of cyclic nucleotide and Ca2+ signalling pathways. In many secretory diarrhoeas, activation of Cl− channels in the apical membrane of enterocytes, including the cystic fibrosis transmembrane conductance regulator and Ca2+-activated Cl− channels, increases fluid secretion, while inhibition of Na+ transport reduces fluid absorption. Current treatment of diarrhoea includes replacement of fluid and electrolyte losses using oral rehydration solutions, and drugs targeting intestinal motility or fluid secretion. Therapeutics in the development pipeline target intestinal ion channels and transporters, regulatory proteins and cell surface receptors. This Review describes pathogenic mechanisms of secretory diarrhoea, current and emerging therapeutics, and the challenges in developing antidiarrhoeal therapeutics. PMID:26122478

  12. Two dimensional nonplanar evolution of electrostatic shock waves in pair-ion plasmas

    SciTech Connect

    Masood, W.; Rizvi, H.

    2012-01-15

    Electrostatic waves in a two dimensional nonplanar geometry are studied in an unmagnetized, dissipative pair-ion plasma in the presence of weak transverse perturbations. The dissipation in the system is taken into account by incorporating the kinematic viscosity of both positive and negative ions in plasmas. The nonplanar Kadomtsev-Petviashvili-Burgers (KPB) as well as the Burgers Kadomtsev-Petviashvili (Burgers KP) equations are derived using the small amplitude expansion method and the range of applicability of both the equations are discussed. The system under consideration is observed to admit compressive rarefactive shocks. The present study may have relevance to understand the formation of two dimensional nonplanar electrostatic shocks in laboratory plasmas.

  13. Nonplanar dust acoustic solitary waves in a strongly coupled dusty plasma with superthermal ions

    SciTech Connect

    El-Labany, S. K. Zedan, N. A.; El-Taibany, W. F. E-mail: eltaibany@du.edu.eg; El-Shamy, E. F.

    2014-12-15

    The nonplanar amplitude modulation of dust acoustic (DA) envelope solitary waves in a strongly coupled dusty plasma (SCDP) has been investigated. By using a reductive perturbation technique, a modified nonlinear Schrödinger equation (NLSE) including the effects of geometry, polarization, and ion superthermality is derived. The modulational instability (MI) of the nonlinear DA wave envelopes is investigated in both planar and nonplanar geometries. There are two stable regions for the DA wave propagation strongly affected by polarization and ion superthermality. Moreover, it is found that the nonlinear DA waves in spherical geometry are the more structurally stable. The larger growth rate of the nonlinear DA MI is observed in the cylindrical geometry. The salient characteristics of the MI in the nonplanar geometries cannot be found in the planar one. The DA wave propagation and the NLSE solutions are investigated both analytically and numerically.

  14. Molecular structures of free-base corroles: nonplanarity, chirality, and enantiomerization.

    PubMed

    Capar, Jan; Conradie, Jeanet; Beavers, Christine M; Ghosh, Abhik

    2015-04-01

    The molecular structures of free-base corroles are illustrative of a variety of bonded and nonbonded interactions including aromaticity, intra- as well as intermolecular hydrogen bonding, steric interactions among multiple NH hydrogens within a congested central cavity, and the effects of peripheral substituents. Against this backdrop, an X-ray structure of 2,3,7,8,12,13,17,18-octabromo-5,10,15-tris(pentafluorophenyl)corrole, H3[Br8TPFPCor], corresponding to a specific tautomer, has been found to exhibit the strongest nonplanar distortions observed to date for any free-base corrole structure. Two adjacent N-protonated pyrrole rings are tilted with respect to each other by approximately 97.7°, while the remainder of the molecule is comparatively planar. Dispersion-corrected DFT calculations were undertaken to investigate to what extent the strong nonplanar distortions can be attributed to steric effects of the peripheral substituents. For meso-triphenylcorrole, DFT calculations revealed nonplanar distortions that are only marginally less pronounced than those found for H3(Br8TPFPCor). A survey of X-ray structures of sterically unhindered corroles also uncovered additional examples of rather strong nonplanar distortions. Detailed potential energy calculations as a function of different saddling dihedrals also emphasized the softness of the distortions. Because of nonplanar distortions, free-base corrole structures are chiral. For H3[Br8TPFPCor], DFT calculations led to an estimate of 15 kcal/mol (0.67 eV) as the activation barrier for enantiomerization of the free-base structures, which is significantly higher than the barrier for NH tautomerism calculated for this molecule, about 5 kcal/mol (0.2 eV). In summary, steric crowding of the internal NH hydrogens appears to provide the main driving force for nonplanar distortions of meso-triarylcorroles; the presence of additional β-substituents adds marginally to this impetus. PMID:25819028

  15. Interaction of dust-ion acoustic solitary waves in nonplanar geometry with electrons featuring Tsallis distribution

    SciTech Connect

    Narayan Ghosh, Uday; Chatterjee, Prasanta; Tribeche, Mouloud

    2012-11-15

    The head-on collisions between nonplanar dust-ion acoustic solitary waves are dealt with by an extended version of Poincare-Lighthill-Kuo perturbation method, for a plasma having stationary dust grains, inertial ions, and nonextensive electrons. The nonplanar geometry modified analytical phase-shift after a head-on collision is derived. It is found that as the nonextensive character of the electrons becomes important, the phase-shift decreases monotonically before levelling-off at a constant value. This leads us to think that nonextensivity may have a stabilizing effect on the phase-shift.

  16. Nonplanar Ion-Acoustic Solitons in Electron-Positron-Ion Quantum Plasmas

    NASA Astrophysics Data System (ADS)

    Khan A., S.; Mahmood, S.; Arshad, Mirza M.

    2009-04-01

    The propagation of nonplanar quantum ion-acoustic solitary waves in a dense, unmagnetized electron-positronion (e-p-i) plasma are studied by using the Korteweg-de Vries (KdV) model. The quantum hydrodynamic (QHD) equations are used taking into account the quantum diffraction and quantum statistics corrections. The analytical and numerical solutions of KdV equation reveal that the nonplanar ion-acoustic solitons are modified significantly with quantum corrections and positron concentration, and behave differently in different geometries.

  17. Fabrication of small-scale structures with non-planar features

    SciTech Connect

    Burckel, David B.; Ten Eyck, Gregory A.

    2015-11-19

    The fabrication of small-scale structures is disclosed. A unit-cell of a small-scale structure with non-planar features is fabricated by forming a membrane on a suitable material. A pattern is formed in the membrane and a portion of the substrate underneath the membrane is removed to form a cavity. Resonators are then directionally deposited on the wall or sides of the cavity. The cavity may be rotated during deposition to form closed-loop resonators. The resonators may be non-planar. The unit-cells can be formed in a layer that includes an array of unit-cells.

  18. The interaction of two nonplanar solitary waves in electron-positron-ion plasmas: An application in active galactic nuclei

    SciTech Connect

    EL-Labany, S. K.; Khedr, D. M.; El-Shamy, E. F.; Sabry, R.

    2013-01-15

    In the present research paper, the effect of bounded nonplanar (cylindrical and spherical) geometry on the interaction between two nonplanar electrostatic solitary waves (NESWs) in electron-positron-ion plasmas has been studied. The extended Poincare-Lighthill-Kuo method is used to obtain nonplanar phase shifts after the interaction of the two NESWs. This study is a first attempt to investigate nonplanar phase shifts and trajectories for NESWs in a two-fluid plasma (a pair-plasma) consisting of electrons and positrons, as well as immobile background positive ions in nonplanar geometry. The change of phase shifts and trajectories for NESWs due to the effect of cylindrical geometry, spherical geometry, the physical processes (either isothermal or adiabatic), and the positions of two NESWs are discussed. The present investigation may be beneficial to understand the interaction between two NESWs that may occur in active galactic nuclei.

  19. Porosome: The Universal Secretory Portal in Cells

    NASA Astrophysics Data System (ADS)

    Jena, Bhanu

    2012-10-01

    In the past 50 years it was believed that during cell secretion, membrane-bound secretory vesicles completely merge at the cell plasma membrane resulting in the diffusion of intra-vesicular contents to the cell exterior and the compensatory retrieval of the excess membrane by endocytosis. This explanation made no sense or logic, since following cell secretion partially empty vesicles accumulate as demonstrated in electron micrographs. Furthermore, with the ``all or none'' mechanism of cell secretion by complete merger of secretory vesicle membrane at the cell plasma membrane, the cell is left with little regulation and control of the amount of content release. Moreover, it makes no sense for mammalian cells to possess such `all or none' mechanism of cell secretion, when even single-cell organisms have developed specialized and sophisticated secretory machinery, such as the secretion apparatus of Toxoplasma gondii, the contractile vacuoles in paramecium, or the various types of secretory structures in bacteria. Therefore, in 1993 in a News and Views article in Nature, E. Neher wrote ``It seems terribly wasteful that, during the release of hormones and neurotransmitters from a cell, the membrane of a vesicle should merge with the plasma membrane to be retrieved for recycling only seconds or minutes later.'' This conundrum in the molecular mechanism of cell secretion was finally resolved in 1997 following discovery of the ``Porosome,'' the universal secretory machinery in cells. Porosomes are supramolecular lipoprotein structures at the cell plasma membrane, where membrane-bound secretory vesicles transiently dock and fuse to release inravesicular contents to the outside during cell secretion. In the past decade, the composition of the porosome, its structure and dynamics at nm resolution and in real time, and its functional reconstitution into artificial lipid membrane, have all been elucidated. Since porosomes in exocrine and neuroendocrine cells measure 100-180 nm

  20. Tension/compression asymmetry of grain boundaries with non-planar structure

    NASA Astrophysics Data System (ADS)

    Zhang, Liang; Lu, Cheng; Tieu, Kiet; Michal, Guillaume; Zhang, Jie; Deng, Guanyu

    2016-08-01

    Molecular dynamics simulations were carried out to investigate the mechanical property and the deformation mechanisms of Cu bicrystal with non-planar structured grain boundaries (GBs) under uniaxial tension and compression. The simulation results showed that the non-planar GBs could change their equilibrium configurations under the applied stress, and the deformation mechanisms varied when altering the misorientation angle. The stacking fault energy curve was affected by the stress perpendicular to the slip plane and therefore has an influence on the dislocation nucleation mechanisms. Previous studies have revealed a ubiquitous tension/compression (T/C) strength asymmetry of many ultra-fine or nanocrystalline materials, and a higher compressive strength was usually reported. However, in the present study, the bicrystal samples with non-planar structured GBs show a higher tensile strength than the compressive one. The unusual T/C asymmetry property has an implication that the GBs with non-planar structure can play a significant role in affecting the mechanical properties of nanostructured materials.

  1. An experimental study of the aerodynamic characteristics of planar and non-planar outboard wing planforms

    NASA Technical Reports Server (NTRS)

    Naik, D. A.; Ostowari, C.

    1987-01-01

    A series of wind tunnel experiments have been conducted to investigate the aerodynamic characteristics of several planar and nonplanar wingtip planforms. Seven different configurations: base-line rectangular, elliptical, swept and tapered, swept and tapered with dihedral, swept and tapered with anhedral, rising arc, and drooping arc, were investigated for two different spans. The data are available in terms of coefficient plots of force data, flow visualization photographs, and velocity and pressure flowfield surveys. All planforms, particularly the nonplanar, have some advantages over the baseline rectangular planform. Span efficiencies up to 20-percent greater than baseline are a possibility. However, it is suggested that the span efficiency concept might need refinement for nonplanar wings. Flow survey data show the change in effective span with vortex roll-up. The flow visualization shows the occurrence of mushroom-cell-separation flow patterns at angles of attack corresponding to stall. These grow with an increase in post-stall angle of attack. For the larger aspect ratios, the cells are observed to split into sub-cells at the higher angles of attack. For all angles of attack, some amount of secondary vortex flow is observed for the planar and nonplanar out-board planforms with sweep and taper.

  2. Method of making a nonplanar buried-heterostructure distributed-feedback laser

    SciTech Connect

    Dolan, G.J.; Logan, R.A.; Temkin, H.; Wilt, D.P.

    1987-10-27

    This patent describes a method for making a distributed feedback laser. The method comprises forming a buried heterostructure on a substrate by sequential deposition of layers including an active layer and a cladding layer. The method comprises producing a grating structure on a nonplanar surface of the cladding layer.

  3. Secretory function of adipose tissue.

    PubMed

    Kuryszko, J; Sławuta, P; Sapikowski, G

    2016-01-01

    There are two kinds of adipose tissue in mammals: white adipose tissue - WAT and brown adipose tissue - BAT. The main function of WAT is accumulation of triacylglycerols whereas the function of BAT is heat generation. At present, WAT is also considered to be an endocrine gland that produces bioactive adipokines, which take part in glucose and lipid metabolism. Considering its endocrine function, the adipose tissue is not a homogeneous gland but a group of a few glands which act differently. Studies on the secretory function of WAT began in 1994 after discovery of leptin known as the satiation hormone, which regulates body energy homeostasis and maintainence of body mass. Apart from leptin, the following belong to adipokines: adiponectin, resistin, apelin, visfatin and cytokines: TNF and IL 6. Adiponectin is a polypeptide hormone of antidiabetic, anti-inflammatory and anti-atherogenic activity. It plays a key role in carbohydrate and fat metabolism. Resistin exerts a counter effect compared to adiponectin and its physiological role is to maintain fasting glycaemia. Visfatin stimulates insulin secretion and increases insulin sensitivity and glucose uptake by muscle cells and adipocytes. Apelin probably increases the insulin sensitivity of tissues. TNF evokes insulin resistance by blocking insulin receptors and inhibits insulin secretion. Approximately 30% of circulating IL 6 comes from adipose tissue. It causes insulin resistance by decreasing the expression of insulin receptors, decreases adipogenesis and adiponectin and visfatin secretion, and stimulates hepatic gluconeogenesis. In 2004, Bays introduced the notion of adiposopathy, defined as dysfunction of the adipose tissue, whose main feature is insulin and leptin resistance as well as the production of inflammatory cytokines: TNF and IL 6 and monocyte chemoattractant protein. This means that excess of adipose tissue, especially visceral adipose tissue, leads to the development of a chronic subclinical

  4. Correlations between Raman frequencies and structures for planar and nonplanar metalloporphyrins

    SciTech Connect

    Sparks, L.D.; Anderson, K.K. |; Medforth, C.J.

    1994-05-11

    Resonance Raman spectra were obtained for two series of metalloporphyrins, and frequencies of structure-sensitive Raman lines are correlated with structural changes in the porphyrin macrocycle. In the first series, metal derivatives of tetracyclohexenyltetraphenylporphyrin (TC{sub 6}TPP), the porphinato core size is varied by varying the metal (Ni < Co < Cu), causing little change in the planarity of this nonplanar porphyrin. In the second series, nickel complexes of tetracyclopentenyl-, tetracyclohexenyl-, and tetracycloheptenyltertraphenylporphyrin (NiTc{sub x}TPP, where x = 5-7), the size of the alky ring at the {beta}-carbon positions of the pyrrole rings is varied. In the NiTc{sub x}TPP series, the porphyrin macrocycle becomes significantly more nonplanar as the alkyl ring becomes larger and steric crowding increases. As a consequence of the increasing nonplanarity, the porphyrin core contracts. Correlations between Raman frequencies and structural parameters, including core size and C{sub {alpha}}-N-C{sub {alpha}} angle (obtained from molecular mechanics calculations), are found for both series of porphyrins. These new correlative relationships are compared to similar relationships previously observed for metal octaalkylporphyrins, metal tetraphenylporphyrins, and a series of Ni octaalkyltetraphenylporphyrins. Most importantly, by comparing the metal series (Ni, Co, Cu, Zn, etc.) for differing porphyrin ligands, the authors find a trend toward weaker frequency dependence on core size for the more nonplanar porphyrins. Thus, the applicability of this useful structural correlation is extended to both planar and nonplanar porphyrins. Finally, the differences between these correlative relationships are traced to more fundamental (Badger`s rule) relationships between vibrational frequencies and the length of bond contributing to the total potential energy of the vibrational modes corresponding to the structure-sensitive Raman lines.

  5. Quality control in the secretory assembly line.

    PubMed Central

    Helenius, A

    2001-01-01

    As a rule, only proteins that have reached a native, folded and assembled structure are transported to their target organelles and compartments within the cell. In the secretory pathway of eukaryotic cells, this type of sorting is particularly important. A variety of molecular mechanisms are involved that distinguish between folded and unfolded proteins, modulate their intracellular transport, and induce degradation if they fail to fold. This phenomenon, called quality control, occurs at several levels and involves different types of folding sensors. The quality control system provides a stringent and versatile molecular sorting system that guaranties fidelity of protein expression in the secretory pathway. PMID:11260794

  6. Pressure-Induced Conductivity in a Neutral Nonplanar Spin-Localized Radical.

    PubMed

    Souto, Manuel; Cui, HengBo; Peña-Álvarez, Miriam; Baonza, Valentín G; Jeschke, Harald O; Tomic, Milan; Valentí, Roser; Blasi, Davide; Ratera, Imma; Rovira, Concepció; Veciana, Jaume

    2016-09-14

    There is a growing interest in the development of single-component molecular conductors based on neutral organic radicals that are mainly formed by delocalized planar radicals, such as phenalenyl or thiazolyl radicals. However, there are no examples of systems based on nonplanar and spin-localized C-centered radicals exhibiting electrical conductivity due to their large Coulomb energy (U) repulsion and narrow electronic bandwidth (W) that give rise to a Mott insulator behavior. Here we present a new type of nonplanar neutral radical conductor attained by linking a tetrathiafulvalene (TTF) donor unit to a neutral polychlorotriphenylmethyl radical (PTM) with the important feature that the TTF unit enhances the overlap between the radical molecules as a consequence of short intermolecular S···S interactions. This system becomes semiconducting upon the application of high pressure thanks to increased electronic bandwidth and charge reorganization opening the way to develop a new family of neutral radical conductors. PMID:27281384

  7. Demonstration of the stabilization technique for nonplanar optical resonant cavities utilizing polarization

    SciTech Connect

    Akagi, T.; Araki, S.; Funahashi, Y.; Honda, Y.; Okugi, T.; Omori, T.; Shimizu, H.; Terunuma, N.; Urakawa, J.; Miyoshi, S.; Takahashi, T. Tanaka, R.; Uesugi, Y.; Yoshitama, H.; Sakaue, K.; Washio, M.

    2015-04-15

    Based on our previously developed scheme to stabilize nonplanar optical resonant cavities utilizing polarization caused by a geometric phase in electromagnetic waves traveling along a twisted path, we report an application of the technique for a cavity installed in the Accelerator Test Facility, a 1.3-GeV electron beam accelerator at KEK, in which photons are generated by laser-Compton scattering. We successfully achieved a power enhancement of 1200 with 1.4% fluctuation, which means that the optical path length of the cavity has been controlled with a precision of 14 pm under an accelerator environment. In addition, polarization switching utilizing a geometric phase of the nonplanar cavity was demonstrated.

  8. Demonstration of the stabilization technique for nonplanar optical resonant cavities utilizing polarization

    NASA Astrophysics Data System (ADS)

    Akagi, T.; Araki, S.; Funahashi, Y.; Honda, Y.; Miyoshi, S.; Okugi, T.; Omori, T.; Shimizu, H.; Sakaue, K.; Takahashi, T.; Tanaka, R.; Terunuma, N.; Uesugi, Y.; Urakawa, J.; Washio, M.; Yoshitama, H.

    2015-04-01

    Based on our previously developed scheme to stabilize nonplanar optical resonant cavities utilizing polarization caused by a geometric phase in electromagnetic waves traveling along a twisted path, we report an application of the technique for a cavity installed in the Accelerator Test Facility, a 1.3-GeV electron beam accelerator at KEK, in which photons are generated by laser-Compton scattering. We successfully achieved a power enhancement of 1200 with 1.4% fluctuation, which means that the optical path length of the cavity has been controlled with a precision of 14 pm under an accelerator environment. In addition, polarization switching utilizing a geometric phase of the nonplanar cavity was demonstrated.

  9. A Vector Study of Linearized Supersonic Flow Applications to Nonplanar Problems

    NASA Technical Reports Server (NTRS)

    Martin, John C

    1953-01-01

    A vector study of the partial-differential equation of steady linearized supersonic flow is presented. General expressions which relate the velocity potential in the stream to the conditions on the disturbing surfaces, are derived. In connection with these general expressions the concept of the finite part of an integral is discussed. A discussion of problems dealing with planar bodies is given and the conditions for the solution to be unique are investigated. Problems concerning nonplanar systems are investigated, and methods are derived for the solution of some simple nonplanar bodies. The surface pressure distribution and the damping in roll are found for rolling tails consisting of four, six, and eight rectangular fins for the Mach number range where the region of interference between adjacent fins does not affect the fin tips.

  10. Planar and nonplanar ion acoustic shock waves in relativistic degenerate astrophysical electron-positron-ion plasmas

    NASA Astrophysics Data System (ADS)

    Ata-ur-Rahman, Ali, S.; Mirza, Arshad M.; Qamar, A.

    2013-04-01

    We have studied the propagation of ion acoustic shock waves involving planar and non-planar geometries in an unmagnetized plasma, whose constituents are non-degenerate ultra-cold ions, relativistically degenerate electrons, and positrons. By using the reductive perturbation technique, Korteweg-deVries Burger and modified Korteweg-deVries Burger equations are derived. It is shown that only compressive shock waves can propagate in such a plasma system. The effects of geometry, the ion kinematic viscosity, and the positron concentration are examined on the ion acoustic shock potential and electric field profiles. It is found that the properties of ion acoustic shock waves in a non-planar geometry significantly differ from those in planar geometry. The present study has relevance to the dense plasmas, produced in laboratory (e.g., super-intense laser-dense matter experiments) and in dense astrophysical objects.

  11. Planar and nonplanar ion acoustic shock waves in relativistic degenerate astrophysical electron-positron-ion plasmas

    SciTech Connect

    Ata-ur-Rahman,; Qamar, A.; Ali, S.; Mirza, Arshad M.

    2013-04-15

    We have studied the propagation of ion acoustic shock waves involving planar and non-planar geometries in an unmagnetized plasma, whose constituents are non-degenerate ultra-cold ions, relativistically degenerate electrons, and positrons. By using the reductive perturbation technique, Korteweg-deVries Burger and modified Korteweg-deVries Burger equations are derived. It is shown that only compressive shock waves can propagate in such a plasma system. The effects of geometry, the ion kinematic viscosity, and the positron concentration are examined on the ion acoustic shock potential and electric field profiles. It is found that the properties of ion acoustic shock waves in a non-planar geometry significantly differ from those in planar geometry. The present study has relevance to the dense plasmas, produced in laboratory (e.g., super-intense laser-dense matter experiments) and in dense astrophysical objects.

  12. Molecular Simulation studies of adsorption of polymers on non-planar surfaces: Influence of surface characteristics

    NASA Astrophysics Data System (ADS)

    Venkatakrishnan, Abishek; Shim, Anne; Frost, Aquil; Lewnard, John; Kuppa, Vikram

    2015-03-01

    Molecular simulations are employed to investigate the adsorption of freely rotating polymer chains adsorbing on to non-planar surfaces. Adsorption studies on planar surfaces have been studied extensively and fairly well understood. However, in reality, surfaces are non-planar and cannot be represented using smooth surface models. We investigate the effect of surface characteristics on adsorption via molecular dynamics and Monte Carlo molecular simulations in the NVT ensemble. Both regular (uniform) and irregular (self-affine) roughness parameters are studied. The adsorbed polymer chains are characterized by density and orientation profiles, adsorbed fraction and chain topologies. Our results elucidate the extent to which surface roughness influences adsorption, in competition with other factors such as chain length and monomer-surface interaction. We also demonstrate how both adsorption and desorption can be controlled solely by tuning surface inhomogeneities.

  13. Manifestations of non-planar adsorption geometries of lead pyrenocyanine at the liquid-solid interface.

    PubMed

    Mali, Kunal S; Zöphel, Lukas; Ivasenko, Oleksandr; Müllen, Klaus; De Feyter, Steven

    2013-10-01

    In this work, we provide evidence for multiple non-planar adsorption geometries of a novel pyrenocyanine derivative at the liquid-solid interface under ambient conditions. When adsorbed at the organic liquid-solid interface, lead pyrenocyanine forms well-ordered monolayers that exhibit peculiar non-periodic contrast variation. The different contrast of the adsorbed molecules is attributed to dissimilar adsorption geometries which arise from the non-planar conformation of the molecules. The non-planarity of the molecular backbone in turn arises due to a combination of the angularly extended pyrene subunits and the presence of the large lead ion, which is too big to fit inside the central cavity and thus is located out of the aromatic plane. The two possible locations of the lead atom, namely below and above the aromatic plane, could be identified as depression and protrusion in the central cavity, respectively. The manifestation of such multiple adsorption geometries on the structure of the resultant monolayer is discussed in detail. The packing density of these 2D arrays of molecules could be tuned by heating of the sample wherein the molecular packing changes from a low-density, pseudo six-fold symmetric to a high-density, two-fold symmetric arrangement. Finally, a well-ordered two-component system could be constructed by incorporating C60 molecules in the adlayer of lead pyrenocyanine at the liquid-solid interface.

  14. Nonplanar ion-acoustic two-soliton systems in quantum electron-positron-ion plasmas

    NASA Astrophysics Data System (ADS)

    Mandal, Pankaj Kumar; Ghorui, Malay Kumar; Saha, Asit; Chatterjee, Prasanta

    2015-01-01

    The basic features of planar and nonplanar time dependent ion-acoustic two-soliton systems have been studied in a three component unmagnetized, collisionless quantum plasma consisting of inertialess electrons and positrons. Using the reductive perturbation technique (RPT), we have derived the Korteweg-de Vries equation for our model. The effects of several parameters on the properties of ion-acoustic two-soliton systems in quantum electron-positron-ion plasmas have been discussed in planar and nonplanar geometries. It has been shown that the properties of ion-acoustic two-soliton systems are affected significantly due to cylindrical and spherical geometries. The amplitude of the cylindrical two-soliton system is smaller than that of the spherical two-soliton system for small values of | τ|. The propagation of ion-acoustic two-soliton systems is quite different from the propagation of ion-acoustic two-soliton systems in a nonplanar geometry. The present investigation may have relevance in the study of the propagation of ion-acoustic two-soliton systems in space and laboratory plasmas.

  15. Docking of Secretory Vesicles Is Syntaxin Dependent

    PubMed Central

    de Wit, Heidi; Cornelisse, L. Niels; Toonen, Ruud F.G.; Verhage, Matthijs

    2006-01-01

    Secretory vesicles dock at the plasma membrane before they undergo fusion. Molecular docking mechanisms are poorly defined but believed to be independent of SNARE proteins. Here, we challenged this hypothesis by acute deletion of the target SNARE, syntaxin, in vertebrate neurons and neuroendocrine cells. Deletion resulted in fusion arrest in both systems. No docking defects were observed in synapses, in line with previous observations. However, a drastic reduction in morphologically docked secretory vesicles was observed in chromaffin cells. Syntaxin-deficient chromaffin cells showed a small reduction in total and plasma membrane staining for the docking factor Munc18-1, which appears insufficient to explain the drastic reduction in docking. The sub-membrane cortical actin network was unaffected by syntaxin deletion. These observations expose a docking role for syntaxin in the neuroendocrine system. Additional layers of regulation may have evolved to make syntaxin redundant for docking in highly specialized systems like synaptic active zones. PMID:17205130

  16. Secretory IgA synthesis in Kwashiorkor.

    PubMed

    Beatty, D W; Napier, B; Sinclair-Smith, C C; McCabe, K; Hughes, E J

    1983-09-01

    The synthesis of intestinal secretory IgA was studied in in vitro cultures of duodenal mucosal biopsies from children with Kwashiorkor. Production of secretory IgA was measured by the incorporation of radioactive label and visualized following PAGE and autoradiography. Results obtained before and after nutritional rehabilitation demonstrate an enhanced synthesis of sIgA in children with acute Kwashiorkor. Histological examination of plasma cells in the biopsy tissue confirms a twofold increase in IgA staining plasma cells in acute Kwashiorkor. Peripheral blood B lymphocytes in acute Kwashiorkor however, showed a reduction in IgA synthesis in the acute stage. These results suggest an effective mucosal sIgA response to the increased intestinal antigen load in Kwashiorkor.

  17. Yeast secretory expression of insulin precursors.

    PubMed

    Kjeldsen, T

    2000-09-01

    Since the 1980s, recombinant human insulin for the treatment of diabetes mellitus has been produced using either the yeast Saccharomyces cerevisiae or the prokaryote Escherichia coli. Here, development of the insulin secretory expression system in S. cerevisiae and its subsequent optimisation is described. Expression of proinsulin in S. cerevisiae does not result in efficient secretion of proinsulin or insulin. However, expression of a cDNA encoding a proinsulin-like molecule with deletion of threonine(B30) as a fusion protein with the S. cerevisiae alpha-factor prepro-peptide (leader), followed either by replacement of the human proinsulin C-peptide with a small C-peptide (e.g. AAK), or by direct fusion of lysine(B29) to glycine(A1), results in the efficient secretion of folded single-chain proinsulin-like molecules to the culture supernatant. The secreted single-chain insulin precursor can then be purified and subsequently converted to human insulin by tryptic transpeptidation in organic aqueous medium in the presence of a threonine ester. The leader confers secretory competence to the insulin precursor, and constructed (synthetic) leaders have been developed for efficient secretory expression of the insulin precursor in the yeasts S. cerevisiae and Pichia pastories. The Kex2 endoprotease, specific for dibasic sites, cleaves the leader-insulin precursor fusion protein in the late secretory pathway and the folded insulin precursor is secreted to the culture supernatant. However, the Kex2 endoprotease processing of the pro-peptide-insulin precursor fusion protein is incomplete and a significant part of the pro-peptide-insulin precursor fusion protein is secreted to the culture supernatant in a hyperglycosylated form. A spacer peptide localised between the leader and the insulin precursor has been developed to optimise Kex2 endoprotease processing and insulin precursor fermentation yield. PMID:11030562

  18. Islet secretory granules contain cytochrome b561.

    PubMed

    Mackin, R B; Jones, D P; Noe, B D

    1986-08-01

    A cytochrome has been detected in secretory granules prepared from anglerfish islets of Langerhans. The heme moiety was determined to be of the b type, and the dithionite-reduced cytochrome exhibited an alpha-band maximum at 561 nm with an extinction coefficient of 13.8 mM-1 X cm-1. The protein was present at a concentration of 40 +/- 4 pmol/mg of secretory granule protein. The cytochrome was found to be an integral membrane protein and to be reduced by ascorbic acid but not by NADH, NADPH, reduced glutathione (GSH), or succinate. Because of the similarity to previously characterized secretory granule cytochrome b561's from neuroendocrine tissues, this cytochrome is also referred to as cytochrome b561. Although its function has not yet been elucidated, the apparent specificity for ascorbate suggests that it may be a component of the ascorbate-dependent peptidyl-glycine alpha-amidating monooxygenase system that functions in the amidation of islet hormones. PMID:3525285

  19. RFP tags for labeling secretory pathway proteins

    SciTech Connect

    Han, Liyang; Zhao, Yanhua; Xu, Pingyong; Huan, Shuangyan

    2014-05-09

    Highlights: • Membrane protein Orai1 can be used to report the fusion properties of RFPs. • Artificial puncta are affected by dissociation constant as well as pKa of RFPs. • Among tested RFPs mOrange2 is the best choice for secretory protein labeling. - Abstract: Red fluorescent proteins (RFPs) are useful tools for live cell and multi-color imaging in biological studies. However, when labeling proteins in secretory pathway, many RFPs are prone to form artificial puncta, which may severely impede their further uses. Here we report a fast and easy method to evaluate RFPs fusion properties by attaching RFPs to an environment sensitive membrane protein Orai1. In addition, we revealed that intracellular artificial puncta are actually colocalized with lysosome, thus besides monomeric properties, pKa value of RFPs is also a key factor for forming intracellular artificial puncta. In summary, our current study provides a useful guide for choosing appropriate RFP for labeling secretory membrane proteins. Among RFPs tested, mOrange2 is highly recommended based on excellent monomeric property, appropriate pKa and high brightness.

  20. Non-planar grain boundary structures in fcc metals and their role in nano-scale deformation mechanisms

    NASA Astrophysics Data System (ADS)

    Smith, Laura; Farkas, Diana

    2014-01-01

    This work presents the results of a comparative molecular dynamics study showing that relaxed random grain boundary structures can be significantly non-planar at the nano-scale in fcc metals characterized by low stacking fault values. We studied the relaxed structures of random [1 1 0] tilt boundaries in a polycrystal using interatomic potentials describing Cu and Pd. Grain boundaries presenting non-planar features were observed predominantly for the Cu potential but not for the Pd potential, and we relate these differences to the stacking fault values. We also show that these non-planar structures can have a strong influence on dislocation emission from the grain boundaries as well as on grain boundary strain accommodation processes, such as grain boundary sliding. We studied the loading response in polycrystals of 40 nm grain size to a level of 9% strain and found that the non-planar grain boundaries favour dislocation emission as a deformation mechanism and hinder grain boundary sliding. This has strong implications for the mechanical behaviour of nano-crystalline materials, which is determined by the competition between dislocation activity and grain boundary accommodation of the strain. Thus, the two interatomic potentials for Cu and Pd considered in this work resulted in the same overall stress-strain curve, but significantly different fractions of the strain accommodated by the intergranular versus intragranular deformation mechanisms. Strain localization patterns are also influenced by the non-planarity of the grain boundary structures.

  1. Influence of experimental hypokinesia on gastric secretory function

    NASA Technical Reports Server (NTRS)

    Markova, O. O.; Vavryshchuk, V. I.; Rozvodovskyy, V. I.; Proshcheruk, V. A.

    1980-01-01

    The gastric secretory function of rats was studied in 4, 8, 16 and 30 day hypokinesia. Inhibition of both the gastric juice secretory and acid producing functions was found. The greatest inhibition was observed on day 8 of limited mobility. By days 16 and 30 of the experiment, a tendency of the gastric secretory activity to return to normal was observed, although it remained reduced.

  2. Electron deficient nonplanar β-octachlorovanadylporphyrin as a highly efficient and selective epoxidation catalyst for olefins.

    PubMed

    Kumar, Ravi; Chaudhary, Nikita; Sankar, Muniappan; Maurya, Mannar R

    2015-10-28

    We have synthesized 2,3,7,8,12,13,17,18-octachloro-meso-tetraphenylporphyrinatooxidovanadium(iv) (VOTPPCl8) and characterized by various spectroscopic (UV-Vis, IR and EPR) techniques, MALDI-TOF mass spectrometry and elemental analysis. The DFT optimized structure of VOTPPCl8 in CH3CN exhibited a highly nonplanar saddle shape conformation of the porphyrin macrocycle. The cyclic voltammogram of VOTPPCl8 showed a 500 mV anodic shift in the first ring reduction potential and 220 mV in the first ring oxidation potential compared to VOTPP indicating the electron deficient nature of the porphyrin π-system and further proving the existence of a nonplanar conformation of the macrocycle in solution. Further, VOTPPCl8 exhibited very high thermal stability till 390 °C as indicated in its thermogram. The oxidation state of the metal ion (V(IV)) was confirmed by EPR spectroscopy and VOTPPCl8 exhibited an axial spectrum which corresponds to the axially compressed dxy(1) configuration. VOTPPCl8 was utilised for the selective epoxidation of various olefins in good yields with very high TOF numbers (6566-9650 h(-1)) in the presence of H2O2 as an oxidant and NaHCO3 as a promoter in a CH3CN/H2O mixture. The oxidoperoxidovanadium(v) species is expected to be the intermediate during the catalytic reaction which is probed by (51)V NMR spectroscopy and MALDI-TOF mass analysis. Notably, VOTPPCl8 is stable after the catalytic reaction and doesn't form a μ-oxo dimer due to the highly electron deficient nonplanar porphyrin core and can be reused for several cycles.

  3. Isotonic water transport in secretory epithelia.

    PubMed

    Swanson, C H

    1977-01-01

    The model proposed by Diamond and Bossert [1] for isotonic water transport has received wide acceptance in recent years. It assumes that the local driving force for water transport is a standing osmotic gradient produced in the lateral intercellular spaces of the epithelial cell layer by active solute transport. While this model is based on work done in absorptive epithelia where the closed to open direction of the lateral space and the direction of net transport are the same, it has been proposed that the lateral spaces could also serve as the site of the local osmotic gradients for water transport in secretory epithelia, where the closed to open direction of the lateral space and net transport are opposed, by actively transporting solute out of the space rather than into it. Operation in the backward direction, however, requires a lower than ambient hydrostatic pressure within the lateral space which would seem more likely to cause the space to collapse with loss of function. On the other hand, most secretory epithelia are characterized by transport into a restricted ductal system which is similar to the lateral intercellular space in the absorptive epithelia in that its closed to open direction is the same as that of net transport. In vitro micropuncture studies on the exocrine pancreas of the rabbit indicate the presence of a small but statistically significant increase in juice osmolality, 6 mOsm/kg H(2)O, at the site of electrolyte and water secretion in the smallest extralobular ducts with secretin stimulation which suggests that the ductal system in the secretory epithelia rather than the lateral intercellular space is the site of the local osmotic gradients responsible for isotonic water transport. PMID:331693

  4. A Compact Non-Planar Coil Design for the SFLM Hybrid

    NASA Astrophysics Data System (ADS)

    Hagnestål, A.; Ågren, O.; Moiseenko, V. E.

    2012-08-01

    A non-planar single layer semiconductor coil set for a version of the Straight Field Line Mirror Hybrid concept with reduced magnetic field has been computed. The coil set consists of 30 coils that are somewhat similar to baseball coils with skewed sides. The coil set has been modeled with filamentary current distributions and basic scaling assumptions have been made regarding the coil widths. This coil set is expected to be considerably cheaper than a previous computed coil set. The coils can probably be produced with technologies known today.

  5. Nanoscale dielectric microscopy of non-planar samples by lift-mode electrostatic force microscopy

    NASA Astrophysics Data System (ADS)

    Van Der Hofstadt, M.; Fabregas, R.; Biagi, M. C.; Fumagalli, L.; Gomila, G.

    2016-10-01

    Lift-mode electrostatic force microscopy (EFM) is one of the most convenient imaging modes to study the local dielectric properties of non-planar samples. Here we present the quantitative analysis of this imaging mode. We introduce a method to quantify and subtract the topographic crosstalk from the lift-mode EFM images, and a 3D numerical approach that allows for extracting the local dielectric constant with nanoscale spatial resolution free from topographic artifacts. We demonstrate this procedure by measuring the dielectric properties of micropatterned SiO2 pillars and of single bacteria cells, thus illustrating the wide applicability of our approach from materials science to biology.

  6. Nanoscale dielectric microscopy of non-planar samples by lift-mode electrostatic force microscopy.

    PubMed

    Van Der Hofstadt, M; Fabregas, R; Biagi, M C; Fumagalli, L; Gomila, G

    2016-10-01

    Lift-mode electrostatic force microscopy (EFM) is one of the most convenient imaging modes to study the local dielectric properties of non-planar samples. Here we present the quantitative analysis of this imaging mode. We introduce a method to quantify and subtract the topographic crosstalk from the lift-mode EFM images, and a 3D numerical approach that allows for extracting the local dielectric constant with nanoscale spatial resolution free from topographic artifacts. We demonstrate this procedure by measuring the dielectric properties of micropatterned SiO2 pillars and of single bacteria cells, thus illustrating the wide applicability of our approach from materials science to biology. PMID:27597315

  7. Nanoscale dielectric microscopy of non-planar samples by lift-mode electrostatic force microscopy.

    PubMed

    Van Der Hofstadt, M; Fabregas, R; Biagi, M C; Fumagalli, L; Gomila, G

    2016-10-01

    Lift-mode electrostatic force microscopy (EFM) is one of the most convenient imaging modes to study the local dielectric properties of non-planar samples. Here we present the quantitative analysis of this imaging mode. We introduce a method to quantify and subtract the topographic crosstalk from the lift-mode EFM images, and a 3D numerical approach that allows for extracting the local dielectric constant with nanoscale spatial resolution free from topographic artifacts. We demonstrate this procedure by measuring the dielectric properties of micropatterned SiO2 pillars and of single bacteria cells, thus illustrating the wide applicability of our approach from materials science to biology.

  8. Immunomodulatory action of mycobacterial secretory proteins.

    PubMed

    Trajkovic, Vladimir; Natarajan, Krishnamurthy; Sharma, Pawan

    2004-04-01

    The recently discovered RD1 locus encodes proteins that are actively secreted by pathogenic mycobacteria, including Mycobacterium tuberculosis. Since they are missing in non-tuberculous mycobacteria, these proteins are promising not only as candidates for vaccination and diagnostic tests, but also in understanding mycobacterial evasion of protective immunity in susceptible individuals. Here we analyze the possible role of M. tuberculosis secretory proteins in immunity against tuberculosis, with emphasis on their immunomodulatory action and the potential involvement in mycobacterial subversion of the host immune defense.

  9. "Secretory" Carcinoma of the Skin Mimicking Secretory Carcinoma of the Breast: Case Report and Literature Review.

    PubMed

    Huang, Sixia; Liu, Yan; Su, Jing; Liu, Jianying; Guo, Xiaoning; Mei, Fang; Zheng, Jie; Liao, Songlin

    2016-09-01

    Secretory carcinoma is a unique kind of adenocarcinoma. It has distinct histological features and a special genetic change, that is, t (12; 15) (p13; q25) translocation which leads to the expression of the ETV6-NTRK3 fusion gene. Secretory carcinoma has been found to occur both in the breast and salivary gland. Here the authors present a case of 22-year-old woman with a unique cutaneous neoplasm located at the axilla. The tumor was characterized histologically with the formation of round to ovoid microcysts and papillary structure, which was similar to the secretory carcinoma of the breast and salivary gland. Furthermore, the gene sequence analysis of reverse-transcription polymerase chain reaction products demonstrated the expression of the ETV6-NTRK3 fusion gene. To the authors' knowledge, this is the first case of secretory carcinoma from the skin which has the same genetic change as those from the breast and salivary gland. Local excision was performed on this patient. She had been followed up for nearly 1 year. No recurrence or metastasis was found yet. PMID:26981741

  10. The interaction between two planar and nonplanar quantum electron acoustic solitary waves in dense electron-ion plasmas

    SciTech Connect

    EL-Labany, S. K.; El-Mahgoub, M. G.; EL-Shamy, E. F.

    2012-06-15

    The interaction between two planar and nonplanar (cylindrical and spherical) quantum electron acoustic solitary waves (QEASWs) in quantum dense electron-ion plasmas has been studied. The extended Poincare-Lighthill-Kuo method is used to obtain planar and nonplanar phase shifts after the interaction of the two QEASWs. The change of phase shifts and trajectories for QEASWs due to the effect of the different geometries, the quantum corrections of diffraction, and the cold electron-to-hot electron number density ratio are discussed. It is shown that the interaction of the QEASWs in planar geometry, cylindrical geometry, and spherical geometry are different. The present investigation may be beneficial to understand the interaction between two planar and nonplanar QEASWs that may occur in the quantum plasmas found in laser-produced plasmas as well as in astrophysical plasmas.

  11. The interaction between two planar and nonplanar quantum electron acoustic solitary waves in dense electron-ion plasmas

    NASA Astrophysics Data System (ADS)

    EL-Labany, S. K.; EL-Shamy, E. F.; El-Mahgoub, M. G.

    2012-06-01

    The interaction between two planar and nonplanar (cylindrical and spherical) quantum electron acoustic solitary waves (QEASWs) in quantum dense electron-ion plasmas has been studied. The extended Poincaré-Lighthill-Kuo method is used to obtain planar and nonplanar phase shifts after the interaction of the two QEASWs. The change of phase shifts and trajectories for QEASWs due to the effect of the different geometries, the quantum corrections of diffraction, and the cold electron-to-hot electron number density ratio are discussed. It is shown that the interaction of the QEASWs in planar geometry, cylindrical geometry, and spherical geometry are different. The present investigation may be beneficial to understand the interaction between two planar and nonplanar QEASWs that may occur in the quantum plasmas found in laser-produced plasmas as well as in astrophysical plasmas.

  12. Secretory pattern of canine growth hormone

    SciTech Connect

    French, M.B.; Vaitkus, P.; Cukerman, E.; Sirek, A.; Sirek, O.V.

    1987-02-01

    The aim of this paper was to define the secretory pattern of growth hormone (GH) under basal conditions in fasted, conscious, male dogs accustomed to handling. Blood samples were withdrawn from a cephalic vein at 15-min intervals. In this way, any ultradian rhythms, if present, could be detected within the frequency range of 0.042-2 cycles/h. In addition, samples were drawn at either 1- or 2.5-min intervals for 2.5 or 5 h to determine whether frequency components greater than 2 cycles/h were present. GH was measured by radioimmunoassay and the raw data were submitted to time series analysis employing power spectral estimation by means of fast Fourier transformation techniques. Peak plasma levels were up to 12 times higher than the baseline concentration of approx. 1 ng/ml. Spectral analysis revealed an endogenous frequency of 0.22 cycles/h, i.e., a periodicity of 4.5 h/cycle. The results indicate that under basal conditions the secretory bursts of canine GH are limited to one peak every 4.5 h.

  13. ATP: The crucial component of secretory vesicles.

    PubMed

    Estévez-Herrera, Judith; Domínguez, Natalia; Pardo, Marta R; González-Santana, Ayoze; Westhead, Edward W; Borges, Ricardo; Machado, José David

    2016-07-12

    The colligative properties of ATP and catecholamines demonstrated in vitro are thought to be responsible for the extraordinary accumulation of solutes inside chromaffin cell secretory vesicles, although this has yet to be demonstrated in living cells. Because functional cells cannot be deprived of ATP, we have knocked down the expression of the vesicular nucleotide carrier, the VNUT, to show that a reduction in vesicular ATP is accompanied by a drastic fall in the quantal release of catecholamines. This phenomenon is particularly evident in newly synthesized vesicles, which we show are the first to be released. Surprisingly, we find that inhibiting VNUT expression also reduces the frequency of exocytosis, whereas the overexpression of VNUT drastically increases the quantal size of exocytotic events. To our knowledge, our data provide the first demonstration that ATP, in addition to serving as an energy source and purinergic transmitter, is an essential element in the concentration of catecholamines in secretory vesicles. In this way, cells can use ATP to accumulate neurotransmitters and other secreted substances at high concentrations, supporting quantal transmission.

  14. Spiperone: evidence for uptake into secretory granules.

    PubMed Central

    Dannies, P S; Rudnick, M S; Fishkes, H; Rudnick, G

    1984-01-01

    Spiperone, a dopamine antagonist widely used as a specific ligand for dopamine and serotonin receptors, is actively accumulated into the F4C1 strain of rat pituitary tumor cells. The accumulation of 10 nM [3H]spiperone was linear for 3 min and reached a steady state after 10 min. Spiperone accumulation was reduced 50% by preincubation with 5 microM reserpine, an inhibitor of biogenic amine transport into secretory granules, and was also blocked by monensin and ammonium chloride, both of which increase the pH of intracellular storage organelles. Uptake was not affected by replacing sodium in the buffer with lithium at equimolar concentrations. Spiperone at 1 microM inhibited by over 50% serotonin transport into membrane vesicles isolated from platelet dense granules; this concentration inhibited the Na+-dependent plasma membrane transport system less than 10%. The data indicate spiperone specifically interacts with the secretory granule amine transport system and suggest that this transport system is found in the F4C1 pituitary cell strain as well as in platelets and neurons. The data also suggest that experiments utilizing spiperone to measure dopamine and serotonin receptors be interpreted with caution. PMID:6584920

  15. Copper trafficking to the secretory pathway.

    PubMed

    Lutsenko, Svetlana

    2016-09-01

    Copper (Cu) is indispensible for growth and development of human organisms. It is required for such fundamental and ubiquitous processes as respiration and protection against reactive oxygen species. Cu also enables catalytic activity of enzymes that critically contribute to the functional identity of many cells and tissues. Pigmentation, production of norepinephrine by the adrenal gland, the key steps in the formation of connective tissue, neuroendocrine signaling, wound healing - all these processes require Cu and depend on Cu entering the secretory pathway. To reach the Cu-dependent enzymes in a lumen of the trans-Golgi network and various vesicular compartments, Cu undertakes a complex journey crossing the extracellular and intracellular membranes and staying firmly on course while traveling in a cytosol. The proteins that assist Cu in this journey by mediating its entry, distribution, and export, have been identified. The accumulating data also indicate that the current model of cellular Cu homeostasis is still a "skeleton" that has to be fleshed out with many new details. This review summarizes recent data on the mechanisms responsible for Cu transfer to the secretory pathway. The emerging new concepts and gaps in our knowledge are discussed. PMID:27603756

  16. Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units.

    PubMed

    Álvarez, Celedonio M; Barbero, Héctor; Ferrero, Sergio

    2016-09-18

    The main purpose of this video is to show 6 reaction steps of a convergent synthesis and prepare a complex molecule containing up to three nonplanar polyaromatic units, which are two corannulene moieties and a racemic hexahelicene linking them. The compound described in this work is a good host for fullerenes. Several common organic reactions, such as free-radical reactions, C-C coupling or click chemistry, are employed demonstrating the versatility of functionalization that this compound can accept. All of these reactions work for planar aromatic molecules. With subtle modifications, it is possible to achieve similar results for nonplanar polyaromatic compounds.

  17. Effect of an applied electric field on a weakly anchored non-planar Nematic Liquid Crystal (NLC) layer

    NASA Astrophysics Data System (ADS)

    Mema, Ensela; Cummings, Linda J.; Kondic, Lou

    We consider a mathematical model that consists of a NLC layer sandwiched between two parallel bounding plates, across which an external field is applied. We investigate its effect on the director orientation by considering the dielectric and flexoelectric contributions and varying parameters that represent the anchoring conditions and the electric field strength. In particular, we investigate possible director configurations that occur in weakly anchored and non-planar systems. We observe that non-planar anchoring angles destroy any hysteresis seen in a planar system by eliminating the fully vertical director configuration and the ''saturation threshold'' seen in weakly anchored planar Freedericksz cells. Supported by NSF Grant No. DMS-1211713.

  18. Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units.

    PubMed

    Álvarez, Celedonio M; Barbero, Héctor; Ferrero, Sergio

    2016-01-01

    The main purpose of this video is to show 6 reaction steps of a convergent synthesis and prepare a complex molecule containing up to three nonplanar polyaromatic units, which are two corannulene moieties and a racemic hexahelicene linking them. The compound described in this work is a good host for fullerenes. Several common organic reactions, such as free-radical reactions, C-C coupling or click chemistry, are employed demonstrating the versatility of functionalization that this compound can accept. All of these reactions work for planar aromatic molecules. With subtle modifications, it is possible to achieve similar results for nonplanar polyaromatic compounds. PMID:27685440

  19. Elementary framework for cold field emission from quantum-confined, non-planar emitters

    SciTech Connect

    Patterson, A. A. Akinwande, A. I.

    2015-05-07

    For suitably small field emitters, the effects of quantum confinement at the emitter tip may have a significant impact on the emitter performance and total emitted current density (ECD). Since the geometry of a quantum system uniquely determines the magnitude and distribution of its energy levels, a framework for deriving ECD equations from cold field electron emitters of arbitrary geometry and dimensionality is developed. In the interest of obtaining semi-analytical ECD equations, the framework is recast in terms of plane wave solutions to the Schrödinger equation via the use of the Jeffreys-Wentzel-Kramers-Brillouin approximation. To demonstrate the framework's consistency with our previous work and its capabilities in treating emitters with non-planar geometries, ECD equations were derived for the normally unconfined cylindrical nanowire (CNW) and normally confined (NC) CNW emitter geometries. As a function of the emitter radius, the NC CNW emitter ECD profile displayed a strong dependence on the Fermi energy and had an average ECD that exceeded the Fowler-Nordheim equation for typical values of the Fermi energy due to closely spaced, singly degenerate energy levels (excluding electron spin), comparatively large electron supply values, and the lack of a transverse, zero-point energy. Such characteristics suggest that emitters with non-planar geometries may be ideal for emission from both an electron supply and electrostatics perspective.

  20. Conformal growth of anodic nanotubes for dye-sensitized solar cells: part II. Nonplanar electrode.

    PubMed

    Sun, Lidong; Zhang, Sam; Wang, Qing

    2014-02-01

    Anodic titania nanotube array features highly ordered alignment as well as porous nature, and exhibits intriguing properties when employed in a variety of applications. All these profit from the continuous efforts on controlling the nanotube configurations. Recently, nonplanar electrodes have also been used to grow the nanotubes besides the conventional planar counterparts. As such, it is of great interest and significance to complete a picture to link the nanotubes grown on planar and various nonplanar electrodes for a comprehensive understanding of nanotube growing manners, in an attempt to boost their future applications. In the first part of this review, planar electrodes are focused with regard to nanotube growth and application in dye-sensitized solar cells. In this part, the nanotubes grown on patterned or curved surfaces are discussed first with reference to a similar structure of alumina nanopores, which are subsequently used to mirror the growth of nanotubes on cylindrical electrodes (i.e., titanium wires or meshes). The last section focuses on titanium tubular electrodes which are attractive for thermal fluids in view of the drastically reduced thermal conductivity in the presence of anodic nanotubes. As a recent hot topic, wire-shaped dye-sensitized solar cells are deliberated in terms of cell structure, efficiency calculation, merits, challenges and outlook.

  1. Rupture Dynamics Simulation for Non-Planar fault by a Curved Grid Finite Difference Method

    NASA Astrophysics Data System (ADS)

    Zhang, Z.; Zhu, G.; Chen, X.

    2011-12-01

    We first implement the non-staggered finite difference method to solve the dynamic rupture problem, with split-node, for non-planar fault. Split-node method for dynamic simulation has been used widely, because of that it's more precise to represent the fault plane than other methods, for example, thick fault, stress glut and so on. The finite difference method is also a popular numeric method to solve kinematic and dynamic problem in seismology. However, previous works focus most of theirs eyes on the staggered-grid method, because of its simplicity and computational efficiency. However this method has its own disadvantage comparing to non-staggered finite difference method at some fact for example describing the boundary condition, especially the irregular boundary, or non-planar fault. Zhang and Chen (2006) proposed the MacCormack high order non-staggered finite difference method based on curved grids to precisely solve irregular boundary problem. Based upon on this non-staggered grid method, we make success of simulating the spontaneous rupture problem. The fault plane is a kind of boundary condition, which could be irregular of course. So it's convinced that we could simulate rupture process in the case of any kind of bending fault plane. We will prove this method is valid in the case of Cartesian coordinate first. In the case of bending fault, the curvilinear grids will be used.

  2. Evaluation of the aromaticity of non-planar and bowl-shaped molecules by NICS criterion.

    PubMed

    Reisi-Vanani, Adel; Rezaei, Ali Asghar

    2015-09-01

    Nucleus independent chemical shift (NICS) criterion was used to gauge the amount of aromaticity in a lot of publications in two last decades. Non-planar molecules with many polygons in different sheets that make angle together have not been studied by this criterion. Perhaps, one ascribes this deficiency to NICS index, but we think it is concern to depauperation in evaluation methods. Therefore, in this work, we try to evaluate aromaticity of two fullerene substructures bowl-shaped molecules, namely corannulene and sumanene as typical non-planar molecules by using of the NICSzz-scan method. The gauge-independent atomic orbital (GIAO) NMR calculations were done at B3LYP/6-311+G(d) level of theory. Energetic criterion as another tool for evaluation of the aromaticity of compounds was used and discussed. Results shows that pentagon and hexagon rings in corannulene have antiaromatic and aromatic character, respectively and in sumanene, pentagon and outer hexagon rings have antiaromatic and aromatic character, respectively. However, the picture obtained based on the NICS computations did not provide any insight towards the real nature of current density in the corannulene and sumanene. PMID:26188797

  3. Stringent limitations on reductive perturbation studies of nonplanar acoustic solitons in plasmas

    NASA Astrophysics Data System (ADS)

    Verheest, Frank; Hellberg, Manfred A.

    2016-06-01

    More than fifty years ago, the Korteweg-de Vries equation was shown to describe not only solitary surface waves on shallow water, but also nonlinear ion-acoustic waves. Because of the algorithmic ease of using reductive perturbation theory, intensive research followed on a wide range of wave types. Soon, the formalism was extended to nonplanar modes by introducing a stretching designed to accommodate spherically and cylindrically symmetric ion-acoustic waves. Over the last two decades many authors followed this approach, but almost all have ignored the severe restrictions in parameter space imposed by the Ansatz. In addition, for other steps in the formalism, the justification is often not spelled out, leading to effects that are physically undesirable or ambiguous. Hence, there is a need to critically assess this approach to nonplanar modes and to use it with the utmost care, respecting the restrictions on its validity. Only inward propagation may be meaningfully studied and respect for weak nonlinearities of at most 1/10 implies that one cannot get closer to the axis or centre of symmetry than about 30 Debye lengths. Thus, one is in a regime where the modes are quasi-planar and not particularly interesting. Most papers disregard these constraints and hence reach questionable conclusions.

  4. Nonplanar integrability

    NASA Astrophysics Data System (ADS)

    Carlson, Warren; de Mello Koch, Robert; Lin, Hai

    2011-03-01

    In this article we study operators with a dimension Δ ˜ O( N) and show that simple analytic expressions for the action of the dilatation operator can be found. The operators we consider are restricted Schur polynomials. There are two distinct classes of operators that we consider: operators labeled by Young diagrams with two long columns or two long rows. The main complication in working with restricted Schur polynomials is in building a projector from a given S n+ m irreducible representation to an S n × S m irreducible representation (both specified by the labels of the restricted Schur polynomial). We give an explicit construction of these projectors by reducing it to the simple problem of addition of angular momentum in ordinary non-relativistic quantum mechanics. The diagonalization of the dilatation operator reduces to solving three term recursion relations. The fact that the recursion relations have only three terms is a direct consequence of the weak mixing at one loop of the restricted Schur polynomials. The recursion relations can be solved exactly in terms of symmetric Kravchuk polynomials or in terms of Clebsch-Gordan coefficients. This proves that the dilatation operator reduces to a decoupled set of harmonic oscillators and therefore it is integrable.

  5. Nonplanar machines

    SciTech Connect

    Ritson, D. )

    1989-05-01

    This talk examines methods available to minimize, but never entirely eliminate, degradation of machine performance caused by terrain following. Breaking of planar machine symmetry for engineering convenience and/or monetary savings must be balanced against small performance degradation, and can only be decided on a case-by-case basis. 5 refs.

  6. 21 CFR 866.5380 - Free secretory component immuno-logical test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... immunochemical techniques free secretory component (normally a portion of the secretory IgA antibody molecule) in body fluids. Measurement of free secretory component (protein molecules) aids in the diagnosis...

  7. 21 CFR 866.5380 - Free secretory component immuno-logical test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... immunochemical techniques free secretory component (normally a portion of the secretory IgA antibody molecule) in body fluids. Measurement of free secretory component (protein molecules) aids in the diagnosis...

  8. Ovarian serous carcinogenesis from tubal secretory cells.

    PubMed

    Zhang, Wenjing; Wei, Linxuan; Li, Lingmin; Yang, Binlie; Kong, Beihua; Yao, Guang; Zheng, Wenxin

    2015-11-01

    Due to a poor understanding of tumorigenesis, ovarian cancers remain the most lethal gynecologic malignancy and cause horrific deaths. In the last decade, a new dualistic model for ovarian cancer was proposed, wherein ovarian serous cancers are classified as either high-grade or low-grade, with each having different tumorigenic processes, and pathologic and clinical features. Surprisingly, both high- and low-grade ovarian serous cancers were recently found to originate not in the ovaries, but rather from the secretory cells of the fallopian tube, mostly from the tubal fimbriated ends. In this article, we review the evidentiary basis for the aforementioned paradigm shift in the cell origin of ovarian serous cancers, as well as its potential clinical implications. PMID:26174492

  9. Some features of secretory systems in plants.

    PubMed

    Juniper, B E; Gilchrist, A J; Robins, R J

    1977-09-01

    Recent work on secretion in plants is reviewed, with emphasis on the anatomy and physiology of root cap cells in higher plants, the stalked glands of Drosera capensis, and the secretory mechanism of Dionaea muscipula. Cells of the root cap of higher plants switch from a geo-perceptive role to one of mucilage secretion at maturation. Features of this process, the role of the Golgi and the pathway for mucilage distribution are reviewed. In contrast, the stalked glands of the leaves of Drosera capensis are much longer lived and have a complex anatomy. The mechanisms for mucilage secretion, protein absorption and the role of the cell membranes in the internal secretion of the protein are described, using data from X-ray microscopv. The secretion of fluid and protein by Dionaea is stimulated by various nitrogen-containing compounds. Uric acid, often excreted by captured insects, is particularly effective in this respect.

  10. Secretory component: a glandular epithelial cell marker.

    PubMed Central

    Harris, J. P.; South, M. A.

    1981-01-01

    Secretory component (SC) has been demonstrated to be produced by both normal and malignantly transformed glandular epithelial cells. By an indirect immunofluorescent technique, this study surveys tumors of varied cellular origin in order to determine the reliability of SC as a marker for tumor cells derived from glandular epithelium. Both primary and metastatic tumors of glandular epithelial origin demonstrated SC fluorescence, while nonglandular epithelial tumors did not. This observation was extended to live single-cell preparations, which demonstrated intense cell-surface fluorescence only when glandular epithelial tumors cells were examined. Additionally, fixed, cytocentrifuged, single-cell preparations of glandular epithelial tumors demonstrated cytoplasmic SC fluorescence. When breast carcinoma was examined, all cases demonstrated SC, regardless of the degree of differentiation. This assay appears to have useful clinical application in that the finding of SC provides indication of the glandular epithelial origin of a malignantly transformed cell. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:6271014

  11. Secretory vesicle swelling by atomic force microscopy.

    PubMed

    Cho, Sang-Joon; Jena, Bhanu P

    2006-01-01

    The swelling of secretory vesicles has been implicated in exocytosis, but the underlying mechanism of vesicle swelling remained unknown. Earlier studies from our laboratory demonstrated the association of the alpha-subunit of heterotrimeric GTP-binding protein G(alphai3) with zymogen granule membrane and implicated its involvement in vesicle swelling. Mas7, an active mastoparan analog known to stimulate Gi proteins, was found to stimulate the GTPase activity of isolated zymogen granules and cause swelling. Increase in vesicle size in the presence of GTP, NaF, and Mas7 were irreversible and found to be KCl sensitive. However, Ca2+ had no effect on zymogen granule size. Taken together, these results indicated that zymogen granules, the membrane-bound secretory vesicles in exocrine pancreas, swell in response to GTP mediated by a G(alphai3) protein. Subsequently, our studies demonstrated that the water channel aquaporin-1 (AQP1) is also present at the zymogen granule membrane and participates in rapid GTP-induced and G(alphai3)-mediated vesicular water gating and swelling. Isolated zymogen granules exhibit low basal water permeability. However, exposure of granules to GTP results in a marked potentiation of water entry. Treatment of zymogen granules with the known water channel inhibitor Hg2+ is accompanied by a reversible loss in both the basal and GTP-stimulable water entry and vesicle swelling. Introduction of AQP1-specific antibody raised against the carboxy-terminal domain of AQP1 blocked GTP-stimulable swelling of vesicles. Our results demonstrate that AQPI associated at the zymogen granule membrane is involved in basal GTP-induced and G(alphai3)-mediated rapid gating of water into zymogen granules of the exocrine pancreas.

  12. Nanocontact printing of nonplanar substrate by using flexible h-PDMS stamp

    NASA Astrophysics Data System (ADS)

    Jo, Jeongdai; Kim, Kwang-Young; Lee, Eung-Sug; Choi, Byung-Oh

    2006-01-01

    The nanocontact printing process of non-planar substrate was conducted on the substrate as coated with the metal thin film on which the mask's pattern was to be printed by using the flexible h-PDMS stamp. In this study, in order to embody non-planar nanocontact print, the following types of nanostructures which were respectively different in a pattern form, a pattern size and a line width: a straight line type, an oblique line type, an L type and an U type. The mask size is 5 x 5 x 0.9 inch, and the pattern form size is 100nm ~ 500nm where the line width ratio and the pattern space are different and the depth is 200nm. The flexible h-PDMS stamp was fabricated by using VDT-731, SIP 6831.1, Fluka 87927 and HMS-301 as a mold material. The flexible h-PDMS stamp with a high resolution corresponds exactly to the master pattern, and could be replicated a pattern up to the size of 100nm. Also, in the surface characteristic, as a result of measuring the wettability, it could be known that the h-PDMS stamp has the surface characteristic of the hydrophobic and surface energy. The adhesion force and the friction force were very low. In the nanocontact printing of non-planar substrates experiment, a substrate of cylindrical on which the Cr adhesion layer of 100Å and the Au etching layer of 500Å were deposited by using the DC sputter and a substrate of ellipsoidal on which the Ti adhesion layer of 100Å and the Pd etching layer of 500Å were deposited in the form of a thin film, were fabricated, and a pattern was transferred to the substrates where to print by the flexible h-PDMS stamp wet with the SAM solution, and nanostructures had a high resolution without any defect could be fabricated. Also, we are seeking for its applicability to a organic electronic device, flexible electronic display, biological electronic device and the like by optimizing the nanocontact printing process.

  13. Scanning electron microscopy of the endometrium during the secretory phase.

    PubMed Central

    Motta, P M; Andrews, P M

    1976-01-01

    Scanning electron microscopy was used to study the surface morphology of the rabbit endometrium during the secretory phase of the oestrous cycle. The free surfaces of ciliated and of inactive active secretory cells are described. Changes in secretory cell surface morphology resulting from accumulation and secretion of material involve the apparent retraction of microvilli and the formation of one or more bulbous protrusions of the cell's apical surface. These protrusions may be relatively smooth surfaced or exhibit long slender micro-extensions. The protrusions grow in size and are eventually pinched off. Loss of the bulbous protrusions often leaves behind crater-like invaginations of the cell's surface. Secretory cells adjacent to the endometrial glands are the first to exhibit signs of mucin accumulation and secretion. The single cilium of a secretory cell is not apparently affected by the secretory process. Signs of ciliated and secretory cell degeneration, and possible sloughing, are also described. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 PMID:1033932

  14. Aerodynamic sensitivities from subsonic, sonic and supersonic unsteady, nonplanar lifting-surface theory

    NASA Technical Reports Server (NTRS)

    Yates, E. Carson, Jr.

    1987-01-01

    The technique of implicit differentiation has been used in combination with linearized lifting-surface theory to derive analytical expressions for aerodynamic sensitivities (i.e., rates of change of lifting pressures with respect to general changes in aircraft geometry, including planform variations) for steady or oscillating planar or nonplanar lifting surfaces in subsonic, sonic, or supersonic flow. The geometric perturbation is defined in terms of a single variable, and the user need only provide simple expressions or similar means for defining the continuous or discontinuous global or local perturbation of interest. Example expressions are given for perturbations of the sweep, taper, and aspect ratio of a wing with trapezoidal semispan planform. In addition to direct computational use, the analytical method presented here should provide benchmark criteria for assessing the accuracy of aerodynamic sensitivities obtained by approximate methods such as finite geometry perturbation and differencing. The present process appears to be readily adaptable to more general surface-panel methods.

  15. Fabrication of non-planar silver nano-arc-gap arrays.

    PubMed

    Shen, Yang; Liu, Mingkai; Wang, Qianjin; Zhan, Peng; Wang, Zhenlin; Zhu, Qiangzhong; Chen, Xia; Jiang, Shaoji; Wang, Xuehua; Jin, Chongjun

    2012-04-01

    We developed a method to fabricate an array of silver non-planar nano-arc-gaps via inverted hemispherical colloidal lithography and shadow metal evaporation methods. It is found that there is a localized surface plasmon mode which results in extraordinary optical transmission. The electric field is strongly localized at the nano-arc-gap region and therefore induces a resonance that has an ultra-small mode volume of less than 2.44 × 10(-6) μm(3). The ratio of the quality factor to the mode volume is as high as 1.44 × 10(6) μm(-3). This would be valuable for the design of optoelectric circuits. PMID:22398454

  16. Absence of the nonpercolating phase for percolation on the nonplanar Hanoi network

    NASA Astrophysics Data System (ADS)

    Hasegawa, Takehisa; Nogawa, Tomoaki

    2013-03-01

    We investigate bond percolation on the nonplanar Hanoi network (HN-NP), which was studied previously [Boettcher Phys. Rev. EPLEEE81539-375510.1103/PhysRevE.80.041115 80, 041115 (2009)]. We calculate the fractal exponent of a subgraph of the HN-NP, which gives a lower bound for the fractal exponent of the original graph. This lower bound leads to the conclusion that the original system does not have a nonpercolating phase, where only finite-size clusters exist for p>0, or equivalently, that the system exhibits either the critical phase, where infinitely many infinite clusters exist, or the percolating phase, where a unique giant component exists. Monte Carlo simulations support our conjecture.

  17. Traction boundary integral equation (BIE) formulations and applications to nonplanar and multiple cracks

    NASA Astrophysics Data System (ADS)

    Cruse, Thomas A.; Novati, Giorgio

    The hypersingular Somigliana identity for the stress tensor is used as the basis for a traction boundary integral equation (BIE) suitable for numerical application to nonplanar cracks and to multiple cracks. The variety of derivations of hypersingular traction BIE formulations is reviewed and extended for this problem class. Numerical implementation is accomplished for piecewise-flat models of curved cracks, using local coordinate system integrations. A nonconforming, triangular boundary element implementation of the integral equations is given. Demonstration problems include several three-dimensional approximations to plane-strain fracture mechanics problems, for which exact or highly accurate numerical solutions exist. In all cases, the use of a piecewise-flat traction BIE implementation is shown to give excellent results.

  18. Stratifying on-shell cluster varieties: the geometry of non-planar on-shell diagrams

    NASA Astrophysics Data System (ADS)

    Bourjaily, Jacob L.; Franco, Sebastián; Galloni, Daniele; Wen, Congkao

    2016-10-01

    The correspondence between on-shell diagrams in maximally supersymmetric Yang-Mills theory and cluster varieties in the Grassmannian remains largely unexplored beyond the planar limit. In this article, we describe a systematic program to survey such `on-shell varieties', and use this to provide a complete classification in the case of G(3 , 6). In particular, we find exactly 24 top-dimensional varieties and 10 co-dimension one varieties in G(3 , 6) — up to parity and relabeling of the external legs. We use this case to illustrate some of the novelties found for non-planar varieties relative to the case of positroids, and describe some of the features that we expect to hold more generally.

  19. Planar and non-planar ion acoustic shock waves in electron positron ion plasmas

    NASA Astrophysics Data System (ADS)

    Masood, Waqas; Jehan, Nusrat; Mirza, Arshad M.; Sakanaka, P. H.

    2008-06-01

    Ion acoustic shock waves (IASW's) are studied in an unmagnetized plasma consisting of electrons, positrons and adiabatically hot positive ions. This is done by deriving the Kortweg-deVries-Burger (KdVB) equation under the small amplitude perturbation expansion method. The dissipation is introduced by taking into account the kinematic viscosity among the plasma constituents. It is found that the strength of ion acoustic shock wave is maximum for spherical, intermediate for cylindrical, and minimum for planar geometry. It is observed that the positron concentration, ratio of ion to electron temperature, and the plasma kinematic viscosity significantly modifies the shock structure. Finally, it is found that the temporal evolution of the non-planar IASW's is quite different by comparison with the planar geometry. The relevance of the present study with regard to the dense astrophysical environments is also pointed out.

  20. Observation of a topological phase by means of a nonplanar Mach-Zehnder interferometer

    SciTech Connect

    Chiao, R.Y.; Antaramian, A.; Ganga, K.M.; Jiao, H.; Wilkinson, S.R.; Nathel, H.

    1988-03-28

    We report the direct observation of a topological phase, i.e., an Aharonov-Bohm-type phase, as a fringe shift in an optical interferometer, which consisted of a modified Mach-Zehnder interferometer, in which the light traveled along nonplanar paths in its two arms. These arms were arranged symmetrically so as to have nearly equal path lengths, but opposite senses of handedness. The relationship between the phase acquired by a circularly polarized light beam and the solid angle subtended by the circuit of the spin vector of a photon in this beam was found to be a linear one with a slope of unity. The sign of the fringe shift also agreed with theory.

  1. A 5 meter range non-planar CMUT array for Automotive Collision Avoidance

    NASA Astrophysics Data System (ADS)

    Hernandez Aguirre, Jonathan

    A discretized hyperbolic paraboloid geometry capacitive micromachined ultrasonic transducer (CMUT) array has been designed and fabricated for automotive collision avoidance. The array is designed to operate at 40 kHz, beamwidth of 40° with a maximum sidelobe intensity of -10dB. An SOI based fabrication technology has been used for the 5x5 array with 5 sensing surfaces along each x and y axis and 7 elevation levels. An assembly and packaging technique has been developed to realize the non-planar geometry in a PGA-68 package. A highly accurate mathematical method has been presented for analytical characterization of capacitive micromachined ultrasonic transducers (CMUTs) built with square diaphragms. The method uses a new two-dimensional polynomial function to more accurately predict the deflection curve of a multilayer square diaphragm subject to both mechanical and electrostatic pressure and a new capacitance model that takes into account the contribution of the fringing field capacitances.

  2. Multi-dimensional modeling of atmospheric copper-sulfidation corrosion on non-planar substrates.

    SciTech Connect

    Chen, Ken Shuang

    2004-11-01

    This report documents the author's efforts in the deterministic modeling of copper-sulfidation corrosion on non-planar substrates such as diodes and electrical connectors. A new framework based on Goma was developed for multi-dimensional modeling of atmospheric copper-sulfidation corrosion on non-planar substrates. In this framework, the moving sulfidation front is explicitly tracked by treating the finite-element mesh as a pseudo solid with an arbitrary Lagrangian-Eulerian formulation and repeatedly performing re-meshing using CUBIT and re-mapping using MAPVAR. Three one-dimensional studies were performed for verifying the framework in asymptotic regimes. Limited model validation was also carried out by comparing computed copper-sulfide thickness with experimental data. The framework was first demonstrated in modeling one-dimensional copper sulfidation with charge separation. It was found that both the thickness of the space-charge layers and the electrical potential at the sulfidation surface decrease rapidly as the Cu{sub 2}S layer thickens initially but eventually reach equilibrium values as Cu{sub 2}S layer becomes sufficiently thick; it was also found that electroneutrality is a reasonable approximation and that the electro-migration flux may be estimated by using the equilibrium potential difference between the sulfidation and annihilation surfaces when the Cu{sub 2}S layer is sufficiently thick. The framework was then employed to model copper sulfidation in the solid-state-diffusion controlled regime (i.e. stage II sulfidation) on a prototypical diode until a continuous Cu{sub 2}S film was formed on the diode surface. The framework was also applied to model copper sulfidation on an intermittent electrical contact between a gold-plated copper pin and gold-plated copper pad; the presence of Cu{sub 2}S was found to raise the effective electrical resistance drastically. Lastly, future research needs in modeling atmospheric copper sulfidation are discussed.

  3. Nonplanar dust-acoustic Gardner solitons in a four-component dusty plasma

    SciTech Connect

    Mannan, A.; Mamun, A. A.

    2011-08-15

    The nonlinear propagation of Gardner solitons (GSs) in a nonplanar (cylindrical and spherical) four-component dusty plasma (composed of inertial positively and negatively dust, Boltzmann electrons, and ions) is studied by the reductive perturbation method. The modified Gardner equation is derived and numerically solved. It has been found that the basic characteristics of the dust-acoustic (DA) GSs, which are shown to exist for {mu} around its critical value {mu}{sub c}[where {mu}=Z{sub dp}m{sub dn}/Z{sub dn}m{sub dp}, Z{sub dn} (Z{sub dp}) is the number of electrons (protons) residing on a negative (positive) dust, m{sub dp} (m{sub dn}) is the mass of the positive (negative) dust, {mu}{sub c} is the value of {mu} corresponding to the vanishing of the nonlinear coefficient of the Korteweg-de Vries (KdV) equation, e.g., {mu}{sub c}{approx_equal}0.174 for {mu}{sub e}=n{sub e0}/Z{sub dn}n{sub dn0}=0.2, {mu}{sub i}=n{sub i0}/Z{sub dn}n{sub dn0}=0.4, and {sigma}=T{sub i}/T{sub e}=0.1, n{sub e0}, n{sub i0}, and n{sub dn0} are, respectively, electron, ion, and dust number densities, and T{sub i} (T{sub e}) is the ion (electron) temperature], are different from those of the KdV solitons, which do not exist for {mu} around {mu}{sub c}. It has been also found that the propagation characteristics of nonplanar DA GSs significantly differ from those of planar ones.

  4. Nonplanar dust-acoustic Gardner solitons in a four-component dusty plasma.

    PubMed

    Mannan, A; Mamun, A A

    2011-08-01

    The nonlinear propagation of Gardner solitons (GSs) in a nonplanar (cylindrical and spherical) four-component dusty plasma (composed of inertial positively and negatively dust, Boltzmann electrons, and ions) is studied by the reductive perturbation method. The modified Gardner equation is derived and numerically solved. It has been found that the basic characteristics of the dust-acoustic (DA) GSs, which are shown to exist for μ around its critical value μ(c) [where μ=Z(dp)m(dn)/Z(dn)m(dp), Z(dn) (Z(dp)) is the number of electrons (protons) residing on a negative (positive) dust, m(dp) (m(dn)) is the mass of the positive (negative) dust, μ(c) is the value of μ corresponding to the vanishing of the nonlinear coefficient of the Korteweg-de Vries (KdV) equation, e.g., μ(c)≃0.174 for μ(e)=n(e0)/Z(dn)n(dn0)=0.2, μ(i)=n(i0)/Z(d)}n(dn0)=0.4, and σ=T(i)/T(e)=0.1, n(e0), n(i0), and n(dn0) are, respectively, electron, ion, and dust number densities, and T(i) (T(e)) is the ion (electron) temperature], are different from those of the KdV solitons, which do not exist for μ around μ(c). It has been also found that the propagation characteristics of nonplanar DA GSs significantly differ from those of planar ones. PMID:21929121

  5. Monoclonal immunoglobulin A antibodies directed against cholera toxin prevent the toxin-induced chloride secretory response and block toxin binding to intestinal epithelial cells in vitro.

    PubMed Central

    Apter, F M; Lencer, W I; Finkelstein, R A; Mekalanos, J J; Neutra, M R

    1993-01-01

    Secretory immunoglobulin A (IgA) antibodies directed against cholera toxin (CT) are thought to be important in resistance to oral challenge with virulent Vibrio cholerae, although alternative mechanisms for protection of intestinal epithelia against CT-induced fluid secretion have been proposed. The ability of anti-CT IgA to block the effects of CT on human enterocytes has not been directly tested because of the lack of a well-defined in vitro intestinal epithelial cell system to directly measure toxin action and the limited availability of purified anti-CT IgA antibodies. We have generated hybridomas that produce monoclonal IgA and IgG antibodies directed against CT by fusion of Peyer's patch cells with mouse myeloma cells after oral-systemic immunization of mice with CT and CT B-subunit protein. All of the anti-CT antibodies recognized the B subunit. Three clones (designated anti-CTB IgA-1, IgA-2, and IgA-3) which produced IgA antibodies in dimeric and polymeric forms were selected. Checkerboard immunoblotting demonstrated that IgA-1 recognized an epitope distinct from that recognized by IgA-2 and IgA-3 and that none of the antibodies were directed against the binding site of GM1, the intestinal cell membrane toxin receptor. The protective capacity of these IgAs was tested in vitro with human T84 colon carcinoma cells grown on permeable supports as confluent monolayers of polarized enterocytes. When each anti-CTB IgA was mixed with 10 nM CT and applied to the apical surfaces of T84 cell monolayers, all three IgAs blocked CT-induced Cl- secretion in a dose-dependent manner and completely inhibited binding of rhodamine-labelled CT to apical cell membranes. Thus, monoclonal anti-CTB IgA antibodies are sufficient to protect human enterocytes in vitro against CT binding and action. Images PMID:7693598

  6. A Novel Mutation of DAX-1 Associated with Secretory Azoospermia

    PubMed Central

    Yang, Lihua; Liu, Yuchen; Diao, Ruiying; Cai, Zhiming; Li, Honggang; Gui, Yaoting

    2015-01-01

    Secretory azoospermia is a severe form of male infertility caused by unknown factors. DAX-1 is predominantly expressed in mammalian reproductive tissues and plays an important role in spermatogenesis because Dax-1 knockout male mice show spermatogenesis defects. To examine whether DAX-1 is involved in the pathogenesis of secretory azoospermia in humans, we sequenced all of the exons of DAX-1 in 776 patients diagnosed with secretory azoospermia and 709 proven fertile men. A number of coding mutations unique to the patient group, including two synonymous mutations and six missense mutations, were identified. Of the missense mutations, our functional assay demonstrated that the V385L mutation caused the reduced functioning of DAX-1. This novel mutation (p. V385L) of DAX-1 is the first to be identified in association with secretory azoospermia, thereby highlighting the important role of DAX-1 in spermatogenesis. PMID:26207377

  7. A Novel Mutation of DAX-1 Associated with Secretory Azoospermia.

    PubMed

    Mou, Lisha; Xie, Nie; Yang, Lihua; Liu, Yuchen; Diao, Ruiying; Cai, Zhiming; Li, Honggang; Gui, Yaoting

    2015-01-01

    Secretory azoospermia is a severe form of male infertility caused by unknown factors. DAX-1 is predominantly expressed in mammalian reproductive tissues and plays an important role in spermatogenesis because Dax-1 knockout male mice show spermatogenesis defects. To examine whether DAX-1 is involved in the pathogenesis of secretory azoospermia in humans, we sequenced all of the exons of DAX-1 in 776 patients diagnosed with secretory azoospermia and 709 proven fertile men. A number of coding mutations unique to the patient group, including two synonymous mutations and six missense mutations, were identified. Of the missense mutations, our functional assay demonstrated that the V385L mutation caused the reduced functioning of DAX-1. This novel mutation (p. V385L) of DAX-1 is the first to be identified in association with secretory azoospermia, thereby highlighting the important role of DAX-1 in spermatogenesis. PMID:26207377

  8. Potential of yeast secretory vesicles in biodelivery systems.

    PubMed

    Kutralam-Muniasamy, Gurusamy; Flores-Cotera, Luis B; Perez-Guevara, Fermin

    2015-06-01

    Membranous vesicular organelles (MVOs), such as secretory vesicles and exosomes, perform a variety of biological functions ranging from secretion to cellular communication in eukaryotic cells. Exosomes, particularly those of mammalian cells, have been widely studied as potential carriers in human therapeutic applications. However, no study has yet demonstrated the use of yeast secretory vesicles for such applications. Therefore, we explore here the current state of knowledge on yeast secretory vesicles and their potential use in therapeutic delivery systems. We focus on the characteristics shared by exosomes and yeast secretory vesicles to provide insights into the use of the latter as delivery vehicles. From this perspective, we speculate on the potential application of post-Golgi vesicles (PGVs) in the biomedical field. PMID:25843637

  9. Secretory protein trafficking in Giardia intestinalis.

    PubMed

    Hehl, Adrian B; Marti, Matthias

    2004-07-01

    Early diverged extant organisms, which may serve as convenient laboratory models to look for and study evolutionary ancient features of eukaryotic cell biology, are rare. The diplomonad Giardia intestinalis, a protozoan parasite known to cause diarrhoeal disease, has become an increasingly popular object of basic research in cell biology, not least because of a genome sequencing project nearing completion. Commensurate with its phylogenetic status, the Giardia trophozoite has a very basic secretory system and even lacks hallmark structures such as a morphologically identifiable Golgi apparatus. The cell's capacity for protein sorting is nevertheless unimpeded, exemplified by its ability to cope with massive amounts of newly synthesized cyst wall proteins and glycans, which are sorted to dedicated Golgi-like compartments termed encystation-specific vesicles (ESVs) generated from endoplasmic reticulum (ER)-derived transport intermediates. This soluble bulk cargo is kept strictly separate from constitutively transported variant surface proteins during export, a function that is dependent on the stage-specific recognition of trafficking signals. Encysting Giardia therefore provide a unique system for the study of unconventional, Golgi-independent protein trafficking mechanisms in the broader context of eukaryotic endomembrane organization and evolution. PMID:15225300

  10. Mammary analogue secretory carcinoma mimicking salivary adenoma.

    PubMed

    Williams, Lindsay; Chiosea, Simion I

    2013-12-01

    Mammary analogue secretory carcinoma (MASC) is a recently described salivary gland tumor characterized by ETV6 translocation. It appears that prior studies have identified MASC by reviewing salivary gland carcinomas, such as acinic cell carcinoma and adenocarcinoma, not otherwise specified. To address the possibility of MASC mimicking benign salivary neoplasms we reviewed 12 salivary gland (cyst)adenomas diagnosed prior to the discovery of MASC. One encapsulated (cyst)adenoma of the parotid gland demonstrated features of MASC. The diagnosis was confirmed by fluorescence in situ hybridization with an ETV6 break-apart probe. An unusual complex pattern of ETV6 rearrangement with duplication of the telomeric/distal ETV6 probe was identified. This case illustrates that MASC may mimic salivary (cyst)adenomas. To more accurately assess true clinical and morphologic spectrum of MASC, future studies may have to include review of salivary (cyst)adenomas. The differential diagnosis of MASC may have to be expanded to include cases resembling salivary (cyst)adenomas.

  11. Methods to Purify and Assay Secretory Pathway Kinases.

    PubMed

    Tagliabracci, Vincent S; Wen, Jianzhong; Xiao, Junyu

    2016-01-01

    Members of the four-jointed and VLK families of secretory pathway kinases appear to be responsible for the phosphorylation of secreted proteins and proteoglycans. These enzymes have been implicated in many biological processes and mutations in several of these kinases cause human diseases. Here, we describe methods to purify and assay two members of the four-jointed family of secretory kinases: the Fam20C protein kinase and the Fam20B proteoglycan kinase. PMID:27632012

  12. Secretory pathway of cellulase: a mini-review

    PubMed Central

    2013-01-01

    Cellulase plays an important role in modern industry and holds great potential in biofuel production. Many different types of organisms produce cellulase, which go through secretory pathways to reach the extracellular space, where enzymatic reactions take place. Secretory pathways in various cells have been the focus of many research fields; however, there are few studies on secretory pathways of cellulases in the literature. It is therefore necessary and important to review the current knowledge on the secretory pathways of cellulases. In this mini-review, we address the subcellular locations of cellulases in different organisms, discuss the secretory pathways of cellulases in different organisms, and examine the secretory mechanisms of cellulases. These sections start with a description of general secreted proteins, advance to the situation of cellulases, and end with the knowledge of cellulases, as documented in UniProt Knowledgebase (UniProtKB). Finally, gaps in existing knowledge are highlighted, which may shed light on future studies for biofuel engineering. PMID:24295495

  13. Study of nonlinear electron-acoustic solitary and shock waves in a dissipative, nonplanar space plasma with superthermal hot electrons

    SciTech Connect

    Han, Jiu-Ning He, Yong-Lin; Luo, Jun-Hua; Nan, Ya-Gong; Han, Zhen-Hai; Dong, Guang-Xing; Duan, Wen-Shan; Li, Jun-Xiu

    2014-01-15

    With the consideration of the superthermal electron distribution, we present a theoretical investigation about the nonlinear propagation of electron-acoustic solitary and shock waves in a dissipative, nonplanar non-Maxwellian plasma comprised of cold electrons, superthermal hot electrons, and stationary ions. The reductive perturbation technique is used to obtain a modified Korteweg-de Vries Burgers equation for nonlinear waves in this plasma. We discuss the effects of various plasma parameters on the time evolution of nonplanar solitary waves, the profile of shock waves, and the nonlinear structure induced by the collision between planar solitary waves. It is found that these parameters have significant effects on the properties of nonlinear waves and collision-induced nonlinear structure.

  14. Numerical optimization techniques for bound circulation distribution for minimum induced drag of Nonplanar wings: Computer program documentation

    NASA Technical Reports Server (NTRS)

    Kuhlman, J. M.; Ku, T. J.

    1981-01-01

    A two dimensional advanced panel far-field potential flow model of the undistorted, interacting wakes of multiple lifting surfaces was developed which allows the determination of the spanwise bound circulation distribution required for minimum induced drag. This model was implemented in a FORTRAN computer program, the use of which is documented in this report. The nonplanar wakes are broken up into variable sized, flat panels, as chosen by the user. The wake vortex sheet strength is assumed to vary linearly over each of these panels, resulting in a quadratic variation of bound circulation. Panels are infinite in the streamwise direction. The theory is briefly summarized herein; sample results are given for multiple, nonplanar, lifting surfaces, and the use of the computer program is detailed in the appendixes.

  15. SGBEM-FEM Alternating Method for Analyzing 3D Non-Planar Cracks and Their Growth in Structural Components

    NASA Technical Reports Server (NTRS)

    Nikishkov, G. P.; Park, J. H.; Atluri, S. N.

    2001-01-01

    The highly accurate and efficient Symmetric Galerkin Boundary Element Method (SGBEM), a Finite Element Method (FEM)-based alternating method, is proposed for analyzing three-dimensional non-planar cracks and their growth. The cracks are modeled using the symmetric Galerkin boundary element method as a distribution of displacement discontinuities, simulating an infinite medium. The finite element method only analyzes the stress for the uncracked body. The solution for the cracked structural component is determined by an iteration procedure. This process alternates between an FEM solution for the uncracked body and the SGBEM solution for a crack in an infinite body. Numerical analysis, and the Java code used, evaluate stress intensity factors and model fatigue crack growth. Examples of non-planar cracks in infinite media and planar cracks in finite bodies, as well as growth under fatigue, show the accuracy of the method.

  16. Time evolution of nonplanar dust ion-acoustic solitary waves in a charge varying dusty plasma with superthermal electrons

    SciTech Connect

    Mayout, Saliha; Tribeche, Mouloud; Sahu, Biswajit

    2015-12-15

    A theoretical study on the nonlinear propagation of nonplanar (cylindrical and spherical) dust ion-acoustic solitary waves (DIASW) is carried out in a dusty plasma, whose constituents are inertial ions, superthermal electrons, and charge fluctuating stationary dust particles. Using the reductive perturbation theory, a modified Korteweg-de Vries equation is derived. It is shown that the propagation characteristics of the cylindrical and spherical DIA solitary waves significantly differ from those of their one-dimensional counterpart.

  17. Frequency stability and offset locking of a laser-diode-pumped Nd:YAG monolithic nonplanar ring oscillator

    NASA Technical Reports Server (NTRS)

    Kane, Thomas J.; Nilsson, Alan C.; Byer, Robert L.

    1987-01-01

    The frequency stability of laser-diode-pumped, monolithic Nd:YAG solid-state unidirectional nonplanar ring oscillators was studied by heterodyne measurements. CW single-axial- and transverse-mode power of 25 mW at 1064 nm was obtained at a slope efficiency of 19 percent. Two independent oscillators were offset-locked at 17 MHz with frequency fluctuations of less than + or - 40 kHz for periods of 8 min.

  18. Nonplanar dust acoustic solitary waves in dusty plasmas with ions and electrons following a q-nonextensive distribution

    SciTech Connect

    Eslami, Parvin; Mottaghizadeh, Marzieh; Pakzad, Hamid Reza

    2011-10-15

    Cylindrical and spherical Korteweg-de Vries equations are derived for dust acoustic solitary waves in an unmagnetized three species plasma system, comprised of negatively charged cold dust, nonextensive ions and nonextensive electrons using standard reductive perturbation method. The effects of q{sub e}-nonextensive electrons, q{sub i}-nonextensive ions, electron-to-ion number density ratio {mu}, and nonplanar geometry on the profiles of the amplitudes of the solitary structures are examined numerically.

  19. 30 Hz-linewidth, diode-laser-pumped, Nd:GGG nonplanar ring oscillators by active frequency stabilisation

    NASA Technical Reports Server (NTRS)

    Day, T.; Nilsson, A. C.; Fejer, M. M.; Farinas, A. D.; Gustafson, E. K.

    1989-01-01

    A heterodyne linewidth of less than 30 Hz for the beatnote between the outputs of two 282 THz Nd:GGG nonplanar ring oscillators (NPROs) is reported. The lasers were independently locked to adjacent axial modes of a high-finesse interferometer. The remnant frequency noise appears to be dominated by free spectral range fluctuations in the reference interferometer rather than by residual laser noise.

  20. Depiction of large angles of view in perspective flight guidance displays through the use of non-planar projections

    NASA Astrophysics Data System (ADS)

    Sindlinger, Andreas; Klingauf, Uwe

    2009-05-01

    Next to flight and system status or sensor data, synthetic vision systems visualize information stored in databases on board of the aircraft in an intuitive manner on flight deck displays. For example, through the three-dimensional depiction of terrain or traffic information on the primary flight display, the pilot's overall situational awareness can be optimized. Today's implementations typically create the image using a perspective projection onto a planar image plane. Commonly, azimuthal angles of view between 30° and about 90° are used for this projection, which significantly limits the peripheral viewing area. Using larger angles of view for the perspective projection leads to a steady increase of compression in the image center and stretches at the image borders. These problems of the depiction of large angles of view have been resolved through the use of a non-planar projection, which projects the image onto a non-planar surface. In order to depict this curved surface on the planar display plane, another projection has to be executed. The non-planar projection allows the depiction of objects on the PFD without length distortions for large angles of view. By depicting large angles of view in synthetic vision systems, elements of the peripheral viewing area can be visualized. Aircraft flying abeam the own aircraft or topographic features like mountain valleys located next to the current aircraft position can be presented to the pilot on the primary flight display. Test flights in a research simulator revealed a strong acceptance of the non-planar projection by the study group of professional pilots.

  1. Block Copolymer Directed Self-Assembly Approaches for Doping Planar and Non-Planar Semiconductors

    NASA Astrophysics Data System (ADS)

    Popere, Bhooshan; Russ, Boris; Heitsch, Andrew; Trefonas, Peter; Segalman, Rachel

    As electronic circuits continue to shrink, reliable nanoscale doping of functional devices presents new challenges. While directed self-assembly (DSA) of block copolymers (BCPs) has enabled excellent pitch control for lithography, controlling the 3D dopant distribution remains a fundamental challenge. To this end, we have developed a BCP self-assembly approach to confine dopants to nanoscopic domains within a semiconductor. This relies on the supramolecular encapsulation of the dopants within the core of the block copolymer (PS- b-P4VP) micelles, self-assembly of these micelles on the substrate, followed by rapid thermal diffusion of the dopants into the underlying substrate. We show that the periodic nature of the BCP domains enables precise control over the dosage and spatial position of dopant atoms on the technologically relevant length scales (10-100 nm). Additionally, as the lateral density of 2D circuit elements approaches the Moore's limit, novel 3D architectures have emerged. We have utilized our BCP self-assembly approach towards understanding the self-assembly our micelles directed by such nanoscale non-planar features. We show that the geometric confinement imposed by the hard feature walls directs the assembly of these micelles.

  2. Elastic wave field computation in multilayered nonplanar solid structures: a mesh-free semianalytical approach.

    PubMed

    Banerjee, Sourav; Kundu, Tribikram

    2008-03-01

    Multilayered solid structures made of isotropic, transversely isotropic, or general anisotropic materials are frequently used in aerospace, mechanical, and civil structures. Ultrasonic fields developed in such structures by finite size transducers simulating actual experiments in laboratories or in the field have not been rigorously studied. Several attempts to compute the ultrasonic field inside solid media have been made based on approximate paraxial methods like the classical ray tracing and multi-Gaussian beam models. These approximate methods have several limitations. A new semianalytical method is adopted in this article to model elastic wave field in multilayered solid structures with planar or nonplanar interfaces generated by finite size transducers. A general formulation good for both isotropic and anisotropic solids is presented in this article. A variety of conditions have been incorporated in the formulation including irregularities at the interfaces. The method presented here requires frequency domain displacement and stress Green's functions. Due to the presence of different materials in the problem geometry various elastodynamic Green's functions for different materials are used in the formulation. Expressions of displacement and stress Green's functions for isotropic and anisotropic solids as well as for the fluid media are presented. Computed results are verified by checking the stress and displacement continuity conditions across the interface of two different solids of a bimetal plate and investigating if the results for a corrugated plate with very small corrugation match with the flat plate results.

  3. A Technique to Transfer Metallic Nanoscale Patterns to Small and Non-Planar Surfaces

    PubMed Central

    Smythe, Elizabeth J.; Dickey, Michael D.; Whitesides, George M.; Capasso, Federico

    2009-01-01

    Conventional lithographic methods (e.g. electron-beam writing, photolithography) are capable of producing high-resolution structures over large areas, but are generally limited to large (>1 cm2) planar substrates. Incorporation of these features on unconventional substrates (i.e., small (<1 mm2) and/or non-planar substrates) would open possibilities for many applications, including remote fiber-based sensing, nanoscale optical lithography, three-dimensional fabrication, and integration of compact optical elements on fiber and semiconductor lasers. Here we introduce a simple method in which a thin thiol-ene film strips arbitrary nanoscale metallic features from one substrate and is then transferred, along with the attached features, to a substrate that would be difficult or impossible to pattern with conventional lithographic techniques. An oxygen plasma removes the sacrificial film, leaving behind the metallic features. The transfer of dense and sparse patterns of isolated and connected gold features ranging from 30 nm to 1 μm, to both an optical fiber facet and a silica microsphere, demonstrates the versatility of the method. A distinguishing feature of this technique is the use of a thin, sacrificial film to strip and transfer metallic nanopatterns and its ability to directly transfer metallic structures produced by conventional lithography. PMID:19206249

  4. High-Reliability Pump Module for Non-Planar Ring Oscillator Laser

    NASA Technical Reports Server (NTRS)

    Liu, Duncan T.; Qiu, Yueming; Wilson, Daniel W.; Dubovitsky, Serge; Forouhar, Siamak

    2007-01-01

    We propose and have demonstrated a prototype high-reliability pump module for pumping a Non-Planar Ring Oscillator (NPRO) laser suitable for space missions. The pump module consists of multiple fiber-coupled single-mode laser diodes and a fiber array micro-lens array based fiber combiner. The reported Single-Mode laser diode combiner laser pump module (LPM) provides a higher normalized brightness at the combined beam than multimode laser diode based LPMs. A higher brightness from the pump source is essential for efficient NPRO laser pumping and leads to higher reliability because higher efficiency requires a lower operating power for the laser diodes, which in turn increases the reliability and lifetime of the laser diodes. Single-mode laser diodes with Fiber Bragg Grating (FBG) stabilized wavelength permit the pump module to be operated without a thermal electric cooler (TEC) and this further improves the overall reliability of the pump module. The single-mode laser diode LPM is scalable in terms of the number of pump diodes and is capable of combining hundreds of fiber-coupled laser diodes. In the proof-of-concept demonstration, an e-beam written diffractive micro lens array, a custom fiber array, commercial 808nm single mode laser diodes, and a custom NPRO laser head are used. The reliability of the proposed LPM is discussed.

  5. Infrared non-planar plasmonic perfect absorber for enhanced sensitive refractive index sensing

    NASA Astrophysics Data System (ADS)

    Cheng, Yongzhi; Mao, Xue Song; Wu, Chenjun; Wu, Lin; Gong, RongZhou

    2016-03-01

    We present a non-planar all-metal plasmonic perfect absorber (PA) with response polarization independent in infrared region, which can be served as a sensor for enhanced refractive index sensing. Distinct from previous designs, the proposed PA consisted of all metal structured film constructed with an assembly of four-tined rod resonators (FRRs). The PA with a high quality-factor (Q-factor) of 41.2 and an absorbance of 99.9% at 142.6 THz has been demonstrated numerically. The resonance behavior occurs in the space between the rods of the FRRs, which is remarkable different conventional sandwiched structural PAs. Based on equivalent LC circuit theory, the absorption peak can be finely tuned by varying the geometrical dimensions of the FRRs. Furthermore, the resonance frequency shows highly sensitive response to the change of refractive index in the surrounding medium. A careful design for refractive index sensor can yield a sensitivity of 1445 nm/refractive index unit (RIU) and a figure of merit (FOM) of 28.8. The demonstrated design of the plasmonic PA for sensing provides great potential application in enhancing refractive index sensors and the enhanced infrared spectroscopy.

  6. Inviscid instabilities of non-planar transversely sheared flows governed by the generalized Rayleigh pressure equation

    NASA Astrophysics Data System (ADS)

    Afsar, Mohammed; Sescu, Adrian

    2014-11-01

    Transition in boundary layer flow over flat/curved surfaces and at moderate to high freestream disturbances or under the influence of various surface roughness elements often involves inviscid secondary instability. This stage in transition can be pictured as being a parametric resonance-type phenomena where a unstable primary flow saturates to a more-or-less steady-state, susceptible to infinitesimal three-dimensional wave-like instability modes that grow much faster than the primary. In decades of research on boundary layers, experimenters have relied upon an inflection point in the wall normal y and/or spanwise directions z of the primary as a pre-cursor to transition. This assertion, based on Rayleigh's theorem, does not however apply in transversely sheared flows. In this talk, we show that an alternative local criterion for inviscid secondary instability - sharing similarities to the original one-dimensional Rayleigh criterion - exists for a class of non-planar transversely sheared flows at long streamwise wavelength. Our general stability criterion is, remarkably, given by necessity of the surface U y , z possessing at least one saddle point in the plane. We analyze this saddle-point criterion numerically show its relevance to secondary instabilities. M.Z.A. would like to anknowledge financial support from Laminar Flow Control (LFC-UK) Research Program at Imperial College London and would like to thank Professor Philip Hall for motivating his interest in this problem.

  7. Bicarbonate transport in sheep parotid secretory cells.

    PubMed Central

    Steward, M C; Poronnik, P; Cook, D I

    1996-01-01

    1. Intracellular pH (pH1) was measured by microfluorimetry in secretory endpieces isolated from sheep parotid glands and loaded with the pH-sensitive fluoroprobe 2', 7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein (BCECF). 2. Stimulation with 1 microM acetylcholine (ACh) caused a large, transient decrease in pH1 of 0.37 +/- 0.02 pH units followed by a slower recovery. The transient, which was reduced by 60% in the absence of HCO3-, could be attributed mainly to HCO3- efflux. During sustained stimulation, pH1 increased to a value that exceeded the resting value by 0.083 +/- 0.023 pH units after 20 min. 3. The anion channel blocker NPPB (0.1 mM) reduced the transient acidification in response to ACh by 48% and raised pH1 during sustained stimulation. Simultaneous application of NPPB and ACh accelerated the re-alkalinization following the initial acidification, indicating that NPPB inhibits HCO3- efflux. 4. The stilbene derivative H2DIDS (0.5 mM) reduced the transient acidification in response to ACh by 76% but caused a marked decrease in pH1 during sustained stimulation. Simultaneous application of H2DIDS and ACh slowed the re-alkalinization following the initial acidification, indicating that the main effect of H2DIDS was to inhibit HCO3- accumulation. 5. In the absence of HCO3-, the recovery from an acid load was unaffected by ACh stimulation. Acid extrusion, although dependent on Na+, was not inhibited by amiloride (1 mM), clonidine (1 mM) or H2DIDS (0.5 mM) and was therefore provisionally attributed to a Na(+)-H+ exchanger isoform other than NHE1 or NHE2. 6. In the presence of HCO3-, the rate of recovery from an acid load was reduced during ACh stimulation, probably as a result of the increased efflux of HCO3-. Acid extrusion was dependent on Na+ and was significantly inhibited by H2DIDS. 7. We conclude that ACh-evoked HCO3- secretion in the sheep parotid gland differs from that in many other salivary glands by being driven predominantly by basolateral Na(+)-HCO3

  8. Stress modulates intestinal secretory immunoglobulin A

    PubMed Central

    Campos-Rodríguez, Rafael; Godínez-Victoria, Marycarmen; Abarca-Rojano, Edgar; Pacheco-Yépez, Judith; Reyna-Garfias, Humberto; Barbosa-Cabrera, Reyna Elizabeth; Drago-Serrano, Maria Elisa

    2013-01-01

    Stress is a response of the central nervous system to environmental stimuli perceived as a threat to homeostasis. The stress response triggers the generation of neurotransmitters and hormones from the hypothalamus pituitary adrenal axis, sympathetic axis and brain gut axis, and in this way modulates the intestinal immune system. The effects of psychological stress on intestinal immunity have been investigated mostly with the restraint/immobilization rodent model, resulting in an up or down modulation of SIgA levels depending on the intensity and time of exposure to stress. SIgA is a protein complex formed by dimeric (dIgA) or polymeric IgA (pIgA) and the secretory component (SC), a peptide derived from the polymeric immunoglobulin receptor (pIgR). The latter receptor is a transmembrane protein expressed on the basolateral side of gut epithelial cells, where it uptakes dIgA or pIgA released by plasma cells in the lamina propria. As a result, the IgA-pIgR complex is formed and transported by vesicles to the apical side of epithelial cells. pIgR is then cleaved to release SIgA into the luminal secretions of gut. Down modulation of SIgA associated with stress can have negative repercussions on intestinal function and integrity. This can take the form of increased adhesion of pathogenic agents to the intestinal epithelium and/or an altered balance of inflammation leading to greater intestinal permeability. Most studies on the molecular and biochemical mechanisms involved in the stress response have focused on systemic immunity. The present review analyzes the impact of stress (mostly by restraint/immobilization, but also with mention of other models) on the generation of SIgA, pIgR and other humoral and cellular components involved in the intestinal immune response. Insights into these mechanisms could lead to better therapies for protecting against pathogenic agents and avoiding epithelial tissue damage by modulating intestinal inflammation. PMID:24348350

  9. Tubal function in chronic secretory otitis media in children.

    PubMed

    Poulsen, G; Tos, M

    1977-01-01

    In 100 children (150 ears) with chronic secretory otitis media the function of the Eustachian tube during treatment with grommet was investigated by air equalisation methods. Tubal function proved poor in the great majority at the beginning of the treatment, but towards its completion there was some improvement. After extrusion of the grommet, tubal function was investigated on the same material by tympanometry. 34% had normal middle-ear pressure initially, and 43% 12-18 months after closure of the perforation. There was no relation between tubal function shown by air equalisation methods and by tympanometry, and the air equalisation methods proved of less value than tympanometry in assessing the course and prognosis of secretory otitis. The pathogenetic theories - the ex vacuo and the secretory theory - are discussed in relation to the chronic tubal dysfunction found to be the most common direct cause of the disease.

  10. Cytoplasmic calcium stimulates exocytosis in a plant secretory cell

    PubMed Central

    Tester, Mark; Zorec, Robert

    1992-01-01

    Although exocytosis is likely to occur in plant cells, the control of this process is the subject of speculation, as no direct measurements of vesicle fusion to the plasma membrane have been made. We used the patch clamp technique to monitor the secretory activity of single aleurone protoplasts by measuring membrane capacitance (Cm), while dialyzing the cytosol with different Ca2+ containing solutions. Secretory activity increased with [Ca2+]i ∼ 1 μM. This demonstrates directly the existence of exocytosis in plant cells, and suggests that both plant and animal cells share common mechanisms (cytosolic Ca2+) for the control of exocytotic secretion. PMID:19431846

  11. Dynamic earthquake rupture simulations on nonplanar faults embedded in 3D geometrically complex, heterogeneous elastic solids

    NASA Astrophysics Data System (ADS)

    Duru, Kenneth; Dunham, Eric M.

    2016-01-01

    Dynamic propagation of shear ruptures on a frictional interface in an elastic solid is a useful idealization of natural earthquakes. The conditions relating discontinuities in particle velocities across fault zones and tractions acting on the fault are often expressed as nonlinear friction laws. The corresponding initial boundary value problems are both numerically and computationally challenging. In addition, seismic waves generated by earthquake ruptures must be propagated for many wavelengths away from the fault. Therefore, reliable and efficient numerical simulations require both provably stable and high order accurate numerical methods. We present a high order accurate finite difference method for: a) enforcing nonlinear friction laws, in a consistent and provably stable manner, suitable for efficient explicit time integration; b) dynamic propagation of earthquake ruptures along nonplanar faults; and c) accurate propagation of seismic waves in heterogeneous media with free surface topography. We solve the first order form of the 3D elastic wave equation on a boundary-conforming curvilinear mesh, in terms of particle velocities and stresses that are collocated in space and time, using summation-by-parts (SBP) finite difference operators in space. Boundary and interface conditions are imposed weakly using penalties. By deriving semi-discrete energy estimates analogous to the continuous energy estimates we prove numerical stability. The finite difference stencils used in this paper are sixth order accurate in the interior and third order accurate close to the boundaries. However, the method is applicable to any spatial operator with a diagonal norm satisfying the SBP property. Time stepping is performed with a 4th order accurate explicit low storage Runge-Kutta scheme, thus yielding a globally fourth order accurate method in both space and time. We show numerical simulations on band limited self-similar fractal faults revealing the complexity of rupture dynamics

  12. Dynamic earthquake rupture simulation on nonplanar faults embedded in 3D geometrically complex, heterogeneous Earth models

    NASA Astrophysics Data System (ADS)

    Duru, K.; Dunham, E. M.; Bydlon, S. A.; Radhakrishnan, H.

    2014-12-01

    Dynamic propagation of shear ruptures on a frictional interface is a useful idealization of a natural earthquake.The conditions relating slip rate and fault shear strength are often expressed as nonlinear friction laws.The corresponding initial boundary value problems are both numerically and computationally challenging.In addition, seismic waves generated by earthquake ruptures must be propagated, far away from fault zones, to seismic stations and remote areas.Therefore, reliable and efficient numerical simulations require both provably stable and high order accurate numerical methods.We present a numerical method for:a) enforcing nonlinear friction laws, in a consistent and provably stable manner, suitable for efficient explicit time integration;b) dynamic propagation of earthquake ruptures along rough faults; c) accurate propagation of seismic waves in heterogeneous media with free surface topography.We solve the first order form of the 3D elastic wave equation on a boundary-conforming curvilinear mesh, in terms of particle velocities and stresses that are collocated in space and time, using summation-by-parts finite differences in space. The finite difference stencils are 6th order accurate in the interior and 3rd order accurate close to the boundaries. Boundary and interface conditions are imposed weakly using penalties. By deriving semi-discrete energy estimates analogous to the continuous energy estimates we prove numerical stability. Time stepping is performed with a 4th order accurate explicit low storage Runge-Kutta scheme. We have performed extensive numerical experiments using a slip-weakening friction law on non-planar faults, including recent SCEC benchmark problems. We also show simulations on fractal faults revealing the complexity of rupture dynamics on rough faults. We are presently extending our method to rate-and-state friction laws and off-fault plasticity.

  13. Episodic slow slip events in a non-planar subduction fault model for northern Cascadia

    NASA Astrophysics Data System (ADS)

    Li, D.; Liu, Y.; Matsuzawa, T.; Shibazaki, B.

    2014-12-01

    Episodic tremor and slow slip (ETS) events have been detected along the Cascadia margin, as well as many other subduction zones, by increasingly dense seismic and geodetic networks over the past decade. In northern Cascadia, ETS events arise on the thrust fault interface of 30~50 km depth, coincident with metamorphic dehydration of the subducting oceanic slab around temperatures of 350. Previous numerical simulations (e.g., Liu and Rice 2007) suggested that near-lithostatic pore pressure in the rate-state friction stability transition zone could give rise to slow slip events (SSE) down-dip of the seismogenic zone, which provides a plausible physical mechanism for these phenomena. Here we present a 3-D numerical simulation of inter-seismic SSEs based on the rate- and state- friction law, incorporating a non-planar, realistic northern Cascadia slab geometry compiled by McCrory et al. (2012) using triangular dislocation elements. Preliminary results show that the width and pore pressure level of the transition zone can remarkably affect the recurrence of SSEs. With effective normal stress of ~1-2 MPa and characteristic slip distance of ~1.4 mm, inter-seismic SSEs can arise about every year. The duration of each event is about 2~3 weeks, with the propagating speed along strike in the range of km/day. Furthermore, the slab bending beneath southern Vancouver Island and northern Washington State appears to accelerate the along-strike propagation of SSEs. Our next step is to constrain the rate-state frictional properties using geodetic inversion of SSE slip and inter-SSE plate coupling from the Plate Boundary Observatory (PBO) GPS measurements. Incorporating the realistic fault geometry into a physics model constrained by geodetic data will enable us to transition from a conceptual towards a quantitative and predictive understanding of SSEs mechanism.

  14. Numerical investigation of blood flow in a deformable coronary bifurcation and non-planar branch

    PubMed Central

    Razavi, Seyed Esmail; Omidi, Amir Ali; Saghafi Zanjani, Massoud

    2014-01-01

    Introduction: Among cardiovascular diseases, arterials stenosis is recognized more commonly than the others. Hemodynamic characteristics of blood play a key role in the incidence of stenosis. This paper numerically investigates the pulsatile blood flow in a coronary bifurcation with a non-planar branch. To create a more realistic analysis, the wall is assumed to be compliant. Furthermore, the flow is considered to be three-dimensional, incompressible, and laminar. Methods: The effects of non-Newtonian blood, compliant walls and different angles of bifurcation on hemodynamic characteristics of flow were evaluated. Shear thinning of blood was simulated with the Carreau-Yasuda model. The current research was mainly focused on the flow characteristics in bifurcations since atherosclerosis occurs mostly in bifurcations. Moreover, as the areas with low shear stresses are prone to stenosis, these areas were identified. Results: Our findings indicated that the compliant model of the wall, bifurcation’s angle, and other physical properties of flow have an impact on hemodynamics of blood flow. Lower wall shear stress was observed in the compliant wall than that in the rigid wall. The outer wall of bifurcation in all models had lower wall shear stress. In bifurcations with larger angles, wall shear stress was higher in outer walls, and lower in inner walls. Conclusion: The non-Newtonian blood vessels and different angles of bifurcation on hemodynamic characteristics of flow evaluation confirmed a lower wall shear stress in the compliant wall than that in the rigid wall, while the wall shear stress was higher in outer walls but lower in inner walls in the bifurcation regions with larger angles. PMID:25671176

  15. Clinical applications of the radioimmunoassay of secretory tuberculoprotein.

    PubMed Central

    Straus, E; Wu, N; Quraishi, M A; Levine, S

    1981-01-01

    A radioimmunoassay that measures a specific secretory tuberculoprotein was used to detect Mycobacterium tuberculosis in 9 of 30 liquid cultures of sputum. The accumulation of immunoreactive material in liquid cultures containing isoniazid was shown to reflect in vitro susceptibility of mycobacteria to the antibiotic effects of the drug. PMID:6789332

  16. The ubiquitin ligase Mindbomb 1 coordinates gastrointestinal secretory cell maturation

    PubMed Central

    Capoccia, Benjamin J.; Jin, Ramon U.; Kong, Young-Yun; Peek, Richard M.; Fassan, Matteo; Rugge, Massimo; Mills, Jason C.

    2013-01-01

    After cell fate specification, differentiating cells must amplify the specific subcellular features required for their specialized function. How cells regulate such subcellular scaling is a fundamental unanswered question. Here, we show that the E3 ubiquitin ligase Mindbomb 1 (MIB1) is required for the apical secretory apparatus established by gastric zymogenic cells as they differentiate from their progenitors. When Mib1 was deleted, death-associated protein kinase–1 (DAPK1) was rerouted to the cell base, microtubule-associated protein 1B (MAP1B) was dephosphorylated, and the apical vesicles that normally support mature secretory granules were dispersed. Consequently, secretory granules did not mature. The transcription factor MIST1 bound the first intron of Mib1 and regulated its expression. We further showed that loss of MIB1 and dismantling of the apical secretory apparatus was the earliest quantifiable aberration in zymogenic cells undergoing transition to a precancerous metaplastic state in mouse and human stomach. Our results reveal a mechanistic pathway by which cells can scale up a specific, specialized subcellular compartment to alter function during differentiation and scale it down during disease. PMID:23478405

  17. Interactions of pathogen-containing compartments with the secretory pathway.

    PubMed

    Canton, Johnathan; Kima, Peter E

    2012-11-01

    A subgroup of intracellular pathogens reside and replicate within membrane-bound compartments often termed pathogen-containing compartments (PCC). PCCs navigate around a wide range of host cell vesicles and organelles. In light of the perils of engaging with vesicles of the endocytic pathway, most PCCs modulate their interactions with endocytic vesicles while a few avoid those interactions. The secretory pathway constitutes another important grouping of vesicles and organelles in host cells. Although the negative consequences of engaging with the secretory pathway are not known, there is evidence that PCCs interact differentially with vesicles and organelles in this pathway as well. In this review, we consider three prokaryote pathogens and two protozoan parasites for which there is information on the interactions of their PCCs with the secretory pathway. Current understandings of the molecular interactions as well as the metabolic benefits that accompany those interactions are discussed. Not unexpectedly, our understanding of the extent of these interactions is variable. An underlying theme that is brought to the fore is that PCCs establish preferential interactions with distinct compartments of the secretory pathway.

  18. Separation of rat pituitary secretory granules by continuous flow electrophoresis

    NASA Technical Reports Server (NTRS)

    Hayes, Daniel; Exton, Carrie; Salada, Thomas; Shellenberger, Kathy; Waddle, Jenny; Hymer, W. C.

    1990-01-01

    The separation of growth hormone-containing cytoplasmic secretory granules from the rat pituitary gland by continuous flow electrophoresis is described. The results are consistent with the hypothesis that granule subpopulations can be separated due to differences in surface charge; these, in turn, may be related to the oligomeric state of the hormone.

  19. Medical management of secretory syndromes related to gastroenteropancreatic neuroendocrine tumours.

    PubMed

    Dimitriadis, Georgios K; Weickert, Martin O; Randeva, Harpal S; Kaltsas, Gregory; Grossman, Ashley

    2016-09-01

    Although recent epidemiological evidence indicates that the prevalence of non-functioning gastroenteropancreatic (GEP) neuroendocrine tumours (NETs) is rising, a significant number of GEP-NETs still present with symptoms related to the secretion of biologically active substances leading to the development of distinct clinical syndromes. In the past, these syndromes were associated with substantial morbidity and mortality due to the lack of specific therapies; however, since the introduction of long-acting somatostatin analogues and medications such as proton pump inhibitors, their control has been greatly improved. As a result, nowadays, the main cause of morbidity and mortality in GEP-NETs is mostly directly related to tumour growth and the extent of metastatic disease. However, in some patients with functioning tumours and extensive disease, control of the secretory syndrome still remains problematic, necessitating the employment of several cytoreductive techniques, which may not always be sufficient. Recently, new agents directed against tumour growth, or exerting increased binding activity to receptors expressed in these tumours, or interfering with the synthetic pathway of some of the compounds secreted by these tumours, have been developed. Since there are no specific guidelines addressing the totality of the management of the secretory syndromes related to GEP-NETs, this review aims at critically analysing the medical management of previously recognised secretory syndromes; it also addresses areas of uncertainty, assesses the newer therapeutic developments and also addresses recently described but poorly characterised secretory syndromes related to GEP-NETs. PMID:27461388

  20. Nonplanar positron-acoustic Gardner solitary waves in electron-positron-ion plasmas with superthermal electrons and positrons

    SciTech Connect

    Uddin, M. J. Alam, M. S.; Mamun, A. A.

    2015-02-15

    Nonplanar (cylindrical and spherical) positron-acoustic (PA) Gardner solitary waves (SWs) in an unmagnetized plasma system consisting of immobile positive ions, mobile cold positrons, and superthermal (kappa distributed) hot positrons and electrons are investigated. The modified Gardner equation is derived by using the reductive perturbation technique. The effects of cylindrical and spherical geometries, superthermal parameter of hot positrons and electrons, relative temperature ratios, and relative number density ratios on the PA Gardner SWs are studied by using the numerical simulations. The implications of our results in various space and laboratory plasma environments are briefly discussed.

  1. Levels and sources of planar and non-planar PCBs in pine needles across Poland.

    PubMed

    Falandysz, Jerzy; Orlikowska, Anna; Jarzyńska, Grażyna; Bochentin, Ilona; Wyrzykowska, Barbara; Drewnowska, Małgorzata; Hanari, Nobuyashi; Horii, Yuichi; Yamashita, Nobuyoshi

    2012-01-01

    Under a small project, one-year-old Scots Pine needles collected from 25 spatially distant sites were examined in monitoring the extent of environmental diffusion and possible sources of polychlorinated biphenyls (PCBs) in ambient air, their depositions and uptake by plants in Poland. The congener-specific determination of planar and non-planar chlorobiphenyls was achieved by isotope dilution HRGC-HRMS method after a highly refined extraction on multi-layer column of silica gel and alumina layer and clean-up, and fractionations, followed by Hypercarb-HPLC and PYE-HPLC sub-fractionation steps. Contents of 117 chlorobiphenyls determined in pine needles varied for the 25 sites studied and is between 2.7 and 49 ng/g wet weight. The PCBs pollution and congener-specific composition of pine needles to some degree varied according to the site or region surveyed depending on population density and industrialization. Many of the country-side areas showed lower concentrations between 2.7 and 8.9 ng/g ww. Pine needles in areas close to well populated and industrial regions of Opole, Kutno, Włocławek and Dębica showed the highest PCB pollution with concentrations varying between 30 and 49 ng/g ww. The Kutno site showed the highest pollution and this fact probably can be explained by possible emission from transformer manufactures located at some distance west of the Kutno area. Factor analysis (FA) and depending on the site revealed on relationship of PCBs composition of pine needles both with highly chlorinated PCB constituents of the mixtures such as Chlorofen, Aroclor 1254, Aroclor 1268 and Sovol but also of lower chlorinated PCB constituents of Aroclor 1242, Aroclor 1248, Clophen A40 or Delor 103. Thermal processes were considered a less significant source of PCBs in ambient air over Poland compared to evaporative sources related to technical PCB formulations. Supplemental materials are available for this article. Go to the publisher's online edition of Journal of

  2. A New Physics-Based Modeling of Multiple Non-Planar Hydraulic Fractures Propagation

    SciTech Connect

    Zhou, Jing; Huang, Hai; Deo, Milind; Jiang, Shu

    2015-10-01

    Because of the low permeability in shale plays, closely spaced hydraulic fractures and multilateral horizontal wells are generally required to improve production. Therefore, understanding the potential fracture interaction and stress evolution is critical in optimizing fracture/well design and completion strategy in multi-stage horizontal wells. In this paper, a novel fully coupled reservoir flow and geomechanics model based on the dual-lattice system is developed to simulate multiple non-planar fractures propagation. The numerical model from Discrete Element Method (DEM) is used to simulate the mechanics of fracture propagations and interactions, while a conjugate irregular lattice network is generated to represent fluid flow in both fractures and formation. The fluid flow in the formation is controlled by Darcy’s law, but within fractures it is simulated by using cubic law for laminar flow through parallel plates. Initiation, growth and coalescence of the microcracks will lead to the generation of macroscopic fractures, which is explicitly mimicked by failure and removal of bonds between particles from the discrete element network. We investigate the fracture propagation path in both homogeneous and heterogeneous reservoirs using the simulator developed. Stress shadow caused by the transverse fracture will change the orientation of principal stress in the fracture neighborhood, which may inhibit or alter the growth direction of nearby fracture clusters. However, the initial in-situ stress anisotropy often helps overcome this phenomenon. Under large in-situ stress anisotropy, the hydraulic fractures are more likely to propagate in a direction that is perpendicular to the minimum horizontal stress. Under small in-situ stress anisotropy, there is a greater chance for fractures from nearby clusters to merge with each other. Then, we examine the differences in fracture geometry caused by fracturing in cemented or uncemented wellbore. Moreover, the impact of

  3. Levels and sources of planar and non-planar PCBs in pine needles across Poland.

    PubMed

    Falandysz, Jerzy; Orlikowska, Anna; Jarzyńska, Grażyna; Bochentin, Ilona; Wyrzykowska, Barbara; Drewnowska, Małgorzata; Hanari, Nobuyashi; Horii, Yuichi; Yamashita, Nobuyoshi

    2012-01-01

    Under a small project, one-year-old Scots Pine needles collected from 25 spatially distant sites were examined in monitoring the extent of environmental diffusion and possible sources of polychlorinated biphenyls (PCBs) in ambient air, their depositions and uptake by plants in Poland. The congener-specific determination of planar and non-planar chlorobiphenyls was achieved by isotope dilution HRGC-HRMS method after a highly refined extraction on multi-layer column of silica gel and alumina layer and clean-up, and fractionations, followed by Hypercarb-HPLC and PYE-HPLC sub-fractionation steps. Contents of 117 chlorobiphenyls determined in pine needles varied for the 25 sites studied and is between 2.7 and 49 ng/g wet weight. The PCBs pollution and congener-specific composition of pine needles to some degree varied according to the site or region surveyed depending on population density and industrialization. Many of the country-side areas showed lower concentrations between 2.7 and 8.9 ng/g ww. Pine needles in areas close to well populated and industrial regions of Opole, Kutno, Włocławek and Dębica showed the highest PCB pollution with concentrations varying between 30 and 49 ng/g ww. The Kutno site showed the highest pollution and this fact probably can be explained by possible emission from transformer manufactures located at some distance west of the Kutno area. Factor analysis (FA) and depending on the site revealed on relationship of PCBs composition of pine needles both with highly chlorinated PCB constituents of the mixtures such as Chlorofen, Aroclor 1254, Aroclor 1268 and Sovol but also of lower chlorinated PCB constituents of Aroclor 1242, Aroclor 1248, Clophen A40 or Delor 103. Thermal processes were considered a less significant source of PCBs in ambient air over Poland compared to evaporative sources related to technical PCB formulations. Supplemental materials are available for this article. Go to the publisher's online edition of Journal of

  4. Planar and non-planar dust ion-acoustic solitary waves in a quantum dusty electronegative plasma

    NASA Astrophysics Data System (ADS)

    Tasnim, S.; Islam, S.; Mamun, A. A.

    2012-03-01

    A theoretical investigation has been made on nonlinear propagation of planar and non-planar solitary waves in a quantum dusty electronegative plasma, whose constituents are quantum electrons, positive ions, negative ions, and arbitrarily charged stationary dust. The reductive perturbation method has been used to derive the Korteweg-de Vries and modified Korteweg-de Vries equations for studying the basic features of solitary waves, which are associated with both positive and negative ion dynamics. The effects of quantum parameter (H), positive and negative ion mass ratio (μin), as well as dust and positive ion number densities (β) on the basic features (polarity, height, and width) of planar solitary waves have been studied. It has been also found that the properties of dust ion-acoustic solitary waves in non-planar cylindrical or spherical geometry differ from those in planar one-dimensional geometry. The implications of our results in space (viz., interstellar compact objects like neutron stars) and laboratory experiments (e.g., intense laser solid density plasma experiments) have been briefly discussed.

  5. Role of aquaporins and regulation of secretory vesicle volume in cell secretion.

    PubMed

    Sugiya, H; Matsuki-Fukushima, M; Hashimoto, S

    2008-01-01

    In exocrine glands, secretory proteins synthesized in the rough endoplasmic reticulum (RER) exhibit vectorial transport from ER through a succession of membrane-bounded components such as Golgi complex, condensing vacuoles and secretory granules. The secretory granules migrate to particular locations within the cell close to the apical membrane prior to the release of their contents into the acinar lumen. Currently, to release intragranular contents, secretory granules have been demonstrated to transiently dock and fuse at 'porosome', a permanent cup-shaped structures at the cell membranes. Then swelling of secretory granules occurs to allow explusion of intragranular contents. In this process, water and ion fluxes in the granule membrane appear to contribute to maintain secretory granule integrity and morphology via osmoregulation in secretory granules. Aquaporins (AQPs) are a family of small, hydrophobic, integral membrane proteins, which function as channels to permeate water and small solutes. The AQPs reside constitutively at the plasma membrane in most cell types. However, recent studies have demonstrated that the AQPs are present in secretory granules in exocrine glands, synaptic vesicles and intracellular vesicles in liver and kidney, implying that AQPs in secretory granules and vesicles are involved in their volume regulation. This paper reviews the possible role of AQPs on secretory granules, especially in exocrine glands, in secretory function.

  6. Secretory function in subplate neurons during cortical development

    PubMed Central

    Kondo, Shinichi; Al-Hasani, Hannah; Hoerder-Suabedissen, Anna; Wang, Wei Zhi; Molnár, Zoltán

    2015-01-01

    Subplate cells are among the first generated neurons in the mammalian cerebral cortex and have been implicated in the establishment of cortical wiring. In rodents some subplate neurons persist into adulthood. Here we would like to highlight several converging findings which suggest a novel secretory function of subplate neurons during cortical development. Throughout the postnatal period in rodents, subplate neurons have highly developed rough endoplasmic reticulum (ER) and are under an ER stress condition. By comparing gene expression between subplate and layer 6, we found that several genes encoding secreted proteins are highly expressed in subplate neurons. One of these secreted proteins, neuroserpin, encoded by the serpini1 gene, is localized to the ER in subplate cells. We propose that subplate might influence cortical circuit formation through a transient secretory function. PMID:25859180

  7. Abnormal apocrine secretory cell mitochondria in a Huntington disease patient.

    PubMed

    Sidiropoulos, Christos; LeWitt, Peter; Hashimoto, Ken

    2012-12-15

    Over two decades, a 42-year old woman experienced the gradual onset of choreic involuntary movements, dystonia, and tics. Decreased caudate nucleus metabolism on 2-deoxyglucose PET scan and a heterozygous 49-CAG repeat expansion within the HTT gene established the diagnosis of HD, although no other family history was known. An axillary skin biopsy revealed a distinctive abnormality of mitochondria limited to the apocrine secretory cells on electron microscopy. All mitochondria were transformed into rounded structures with disrupted cristae and prominent myelin figures; many were enlarged up to 4 times the normal. Cytoplasm of apocrine secretory cells showed an abundance of lipid vacuoles, empty vesicles, and dense bodies. Biopsied skeletal muscle histology (light microscopy) was normal, as was a mitochondrial metabolism study. Biopsies from other HD patients have shown similar mitochondrial changes in cerebral neurons, muscle, fibroblasts, and lymphoblasts, adding to evidence for a systemic disturbance of mitochondria in HD.

  8. Novelties in secretory structures and anatomy of Rhynchosia (Fabaceae).

    PubMed

    De Vargas, Wanderleia; Sartori, Ângela L B; Dias, Edna S

    2015-03-01

    A comparative anatomical study was carried out on the secretory structures of leaflets from taxa belonging to the genus Rhynchosia - taxa difficult to delimit because of uncertain interspecific relations - in order to evaluate the potential diagnostic value of these anatomical traits for taxonomic assignment. A further objective was to establish consensual denomination for these secretory structures. The new anatomical features found in these taxa were sufficiently consistent to separate the species evaluated. The presence and localization of glandular-punctate structures bulbous-based trichomes, the number of layers in the palisade parenchyma and the arrangement of vascular units distinguish the taxa investigated and these characteristics can be extended to other species of Papilionoideae. The trichomes analyzed were described and classified into five types. Depicted in diagrams, photomicrographs, and by scanning electron microscopy, and listed for the first time at the genus and species levels. The information obtained served to effectively distinguish the taxa investigated among species of Papilonoideae.

  9. Isolation of intact sub-dermal secretory cavities from Eucalyptus

    PubMed Central

    2010-01-01

    Background The biosynthesis of plant natural products in sub-dermal secretory cavities is poorly understood at the molecular level, largely due to the difficulty of physically isolating these structures for study. Our aim was to develop a protocol for isolating live and intact sub-dermal secretory cavities, and to do this, we used leaves from three species of Eucalyptus with cavities that are relatively large and rich in essential oils. Results Leaves were digested using a variety of commercially available enzymes. A pectinase from Aspergillus niger was found to allow isolation of intact cavities after a relatively short incubation (12 h), with no visible artifacts from digestion and no loss of cellular integrity or cavity contents. Several measurements indicated the potential of the isolated cavities for further functional studies. First, the cavities were found to consume oxygen at a rate that is comparable to that estimated from leaf respiratory rates. Second, mRNA was extracted from cavities, and it was used to amplify a cDNA fragment with high similarity to that of a monoterpene synthase. Third, the contents of the cavity lumen were extracted, showing an unexpectedly low abundance of volatile essential oils and a sizeable amount of non-volatile material, which is contrary to the widely accepted role of secretory cavities as predominantly essential oil repositories. Conclusions The protocol described herein is likely to be adaptable to a range of Eucalyptus species with sub-dermal secretory cavities, and should find wide application in studies of the developmental and functional biology of these structures, and the biosynthesis of the plant natural products they contain. PMID:20807444

  10. Neuroendocrine secretory protein 7B2: structure, expression and functions.

    PubMed Central

    Mbikay, M; Seidah, N G; Chrétien, M

    2001-01-01

    7B2 is an acidic protein residing in the secretory granules of neuroendocrine cells. Its sequence has been elucidated in many phyla and species. It shows high similarity among mammals. A Pro-Pro-Asn-Pro-Cys-Pro polyproline motif is its most conserved feature, being carried by both vertebrate and invertebrate sequences. It is biosynthesized as a precursor protein that is cleaved into an N-terminal fragment and a C-terminal peptide. In neuroendocrine cells, 7B2 functions as a specific chaperone for the proprotein convertase (PC) 2. Through the sequence around its Pro-Pro-Asn-Pro-Cys-Pro motif, it binds to an inactive proPC2 and facilitates its transport from the endoplasmic reticulum to later compartments of the secretory pathway where the zymogen is proteolytically matured and activated. Its C-terminal peptide can inhibit PC2 in vitro and may contribute to keep the enzyme transiently inactive in vivo. The PC2-7B2 model defines a new neuroendocrine paradigm whereby proteolytic activation of prohormones and proneuropeptides in the secretory pathway is spatially and temporally regulated by the dynamics of interactions between converting enzymes and their binding proteins. Interestingly, unlike PC2-null mice, which are viable, 7B2-null mutants die early in life from Cushing's disease due to corticotropin ('ACTH') hypersecretion by the neurointermediate lobe, suggesting a possible involvement of 7B2 in secretory granule formation and in secretion regulation. The mechanism of this regulation is yet to be elucidated. 7B2 has been shown to be a good marker of several neuroendocrine cell dysfunctions in humans. The possibility that anomalies in its structure and expression could be aetiological causes of some of these dysfunctions warrants investigation. PMID:11439082

  11. Secretory pattern and regulatory mechanism of growth hormone in cattle

    PubMed Central

    2016-01-01

    Abstract The ultradian rhythm of growth hormone (GH) secretion has been known in several animal species for years and has recently been observed in cattle. Although the physiological significance of the rhythm is not yet fully understood, it appears essential for normal growth. In this review, previous studies concerning the GH secretory pattern in cattle, including its ultradian rhythm, are introduced and the regulatory mechanism is discussed on the basis of recent findings. PMID:26260675

  12. Interactions between spontaneous and provoked cortisol secretory episodes in man.

    PubMed

    Brandenberger, G; Follénius, M; Muzet, A

    1984-09-01

    This study describes the interactions between cortisol peaks due to spontaneous episodic release and peaks provoked by external stimuli. Successive and equidistant transitory rises of similar amplitude and duration were produced either by muscular exercise (30 min, 75% VO2max) or by injecting ACTH1-24 (Synacthen: 250 ng) before and after the midday meal-related peak. ACTH1-24 was also injected during sleep before the nocturnal sequence of the major secretory episodes. In all instances, cortisol levels had reverted to basal levels when the second stimulus was applied. ACTH-induced cortisol peaks depressed the subsequent meal-related peaks, the exercise-induced peaks, and the spontaneous secretory episodes at the end of the night, and thus had a strong depressor capacity. When exercise was the prior stimulus, the subsequent meal-related peaks were depressed, but the response to later exercise was not affected. Meal-related peaks and the spontaneous diurnal or nocturnal peaks did not depress the subsequent secretory episodes. These quantitatively comparable cortisol episodes were preceded by ACTH rises whose amplitude and duration were not identical: spontaneous and meal-related ACTH peaks were smaller than the provoked one; exercise-induced ACTH peaks were of longer duration than those after ACTH1-24 injection. The different depressor capacities of similar sized cortisol episodes and the lack of proportionality between spontaneous and provoked ACTH and cortisol peaks suggest that there are separate adrenocortical activation channels, which depend on the origin of the stimulation.

  13. Souffle/Spastizin Controls Secretory Vesicle Maturation during Zebrafish Oogenesis

    PubMed Central

    Riedel, Dietmar; Schomburg, Christoph; Cerdà, Joan; Vollack, Nadine; Dosch, Roland

    2014-01-01

    During oogenesis, the egg prepares for fertilization and early embryogenesis. As a consequence, vesicle transport is very active during vitellogenesis, and oocytes are an outstanding system to study regulators of membrane trafficking. Here, we combine zebrafish genetics and the oocyte model to identify the molecular lesion underlying the zebrafish souffle (suf) mutation. We demonstrate that suf encodes the homolog of the Hereditary Spastic Paraplegia (HSP) gene SPASTIZIN (SPG15). We show that in zebrafish oocytes suf mutants accumulate Rab11b-positive vesicles, but trafficking of recycling endosomes is not affected. Instead, we detect Suf/Spastizin on cortical granules, which undergo regulated secretion. We demonstrate genetically that Suf is essential for granule maturation into secretion competent dense-core vesicles describing a novel role for Suf in vesicle maturation. Interestingly, in suf mutants immature, secretory precursors accumulate, because they fail to pinch-off Clathrin-coated buds. Moreover, pharmacological inhibition of the abscission regulator Dynamin leads to an accumulation of immature secretory granules and mimics the suf phenotype. Our results identify a novel regulator of secretory vesicle formation in the zebrafish oocyte. In addition, we describe an uncharacterized cellular mechanism for Suf/Spastizin activity during secretion, which raises the possibility of novel therapeutic avenues for HSP research. PMID:24967841

  14. Unremitting Cell Proliferation in the Secretory Phase of Eutopic Endometriosis

    PubMed Central

    Franco-Murillo, Yanira; Miranda-Rodríguez, José Antonio; Rendón-Huerta, Erika; Montaño, Luis F.; Cornejo, Gerardo Velázquez; Gómez, Lucila Poblano; Valdez-Morales, Francisco Javier; Gonzalez-Sanchez, Ignacio

    2014-01-01

    Objective: Endometriosis is linked to altered cell proliferation and stem cell markers c-kit/stem cell factor (SCF) in ectopic endometrium. Our aim was to investigate whether c-kit/SCF also plays a role in eutopic endometrium. Design: Eutopic endometrium obtained from 35 women with endometriosis and 25 fertile eumenorrheic women was analyzed for in situ expression of SCF/c-kit, Ki67, RAC-alpha serine/threonine-protein kinase (Akt), phosphorylated RAC-alpha serine/threonin-protein kinase (pAkt), Glycogen synthase kinase 3 beta (GSK3β), and phosphorylated glycogen synthase kinase 3 beta (pGSK3β), throughout the menstrual cycle. Results: Expression of Ki67 and SCF was higher in endometriosis than in control tissue (P < .05) and greater in secretory rather than proliferative (P < .01) endometrium in endometriosis. Expression of c-kit was also higher in endometriosis although similar in both phases. Expression of Akt and GSK3β was identical in all samples and cycle phases, whereas pAkt and pGSK3β, opposed to control tissue, remained overexpressed in the secretory phase in endometriosis. Conclusion: Unceasing cell proliferation in the secretory phase of eutopic endometriosis is linked to deregulation of c-kit/SCF-associated signaling pathways. PMID:25194152

  15. A secretory kinase complex regulates extracellular protein phosphorylation

    PubMed Central

    Cui, Jixin; Xiao, Junyu; Tagliabracci, Vincent S; Wen, Jianzhong; Rahdar, Meghdad; Dixon, Jack E

    2015-01-01

    Although numerous extracellular phosphoproteins have been identified, the protein kinases within the secretory pathway have only recently been discovered, and their regulation is virtually unexplored. Fam20C is the physiological Golgi casein kinase, which phosphorylates many secreted proteins and is critical for proper biomineralization. Fam20A, a Fam20C paralog, is essential for enamel formation, but the biochemical function of Fam20A is unknown. Here we show that Fam20A potentiates Fam20C kinase activity and promotes the phosphorylation of enamel matrix proteins in vitro and in cells. Mechanistically, Fam20A is a pseudokinase that forms a functional complex with Fam20C, and this complex enhances extracellular protein phosphorylation within the secretory pathway. Our findings shed light on the molecular mechanism by which Fam20C and Fam20A collaborate to control enamel formation, and provide the first insight into the regulation of secretory pathway phosphorylation. DOI: http://dx.doi.org/10.7554/eLife.06120.001 PMID:25789606

  16. Alterations in hepatic pericanalicular cytoplasm during enhanced bile secretory activity.

    PubMed

    Jones, A L; Schmucker, D L; Mooney, J S; Ockner, R K; Adler, R D

    1979-04-01

    In an attempt to demonstrate the morphology of the bile secretory apparatus, male rats were restrained and maintained on an isocaloric diet with (experimental) and without (control) taurocholate, which was continuously infused via a duodenal cannula. This method of taurocholate administration promotes a 2-fold increase in the bile acid pool size and bile secretory rate and increases the transport maximum of taurocholate by approximately 50%. After 48 hours, the livers from both the control and experimental animals were perfusion-fixed and whole hepatocytes as well as pericanalicular cytoplasm (defined as a 1-micron. wide zone of cytoplasm adjacent to the bile canaliculus) in both centrolobular and periportal cells were subjected to a stereologic analysis. Although taurocholate infusion produced relatively few changes in the amounts of organelles or inclusionswithin hepatocytes, it caused highly significant increases in the amount ofGolgi-rich area, Golgi membranes, and the number of vesicles with diameters greater than 1000 A in the pericanalicular area of cytoplasm. In addition to these changes, which occurred in both central and periportal zones, decreases in the volume of lysosomes and the surface area of smooth surfaced endoplasmic reticulum were observed. These data provide new evidence that the "bile secretory apparatus" may encompass several hepatocellular components which include the Golgi complex and a vesicular transport system.

  17. RNAi knockdown of parafusin inhibits the secretory pathway.

    PubMed

    Liu, Li; Wyroba, Elzbieta; Satir, Birgit H

    2011-10-01

    Several glycolytic enzymes and their isoforms have been found to be important in cell signaling unrelated to glycolysis. The involvement of parafusin (PFUS), a member of the phosphoglucomutase (PGM) superfamily with no phosphoglucomutase activity, in Ca(2+)-dependent exocytosis has been controversial. This protein was first described in Paramecium tetraurelia, but is widely found. Earlier work showed that parafusin is a secretory vesicle scaffold component with unusual post-translational modifications (cyclic phosphorylation and phosphoglucosylation) coupled to stages in the exocytic process. Using RNAi, we demonstrate that parafusin synthesis can be reversibly blocked, with minor or no effect on other PGM isoforms. PFUS knockdown produces an inhibition of dense core secretory vesicle (DCSV) synthesis leading to an exo(-) phenotype. Although cell growth is unaffected, vesicle content is not packaged properly and no new DCSVs are formed. We conclude that PFUS and its orthologs are necessary for proper scaffold maturation. Because of this association, parafusin is an important signaling component for regulatory control of the secretory pathway.

  18. Analytical description of a Gaussian beam in a ring resonator with a nonplanar axial contour and an odd number of mirrors

    SciTech Connect

    Plachenov, A B; Radin, A M

    2011-01-31

    Stability conditions for a ring resonator with an odd number of mirrors and a nonplanar axial contour are studied analytically. New explicit expressions are derived to describe the transverse field distribution of the Gaussian mode with general astigmatism produced in this resonator. Field characteristics for a resonator with the specified parameters are calculated. (laser beams)

  19. A senescence secretory switch mediated by PI3K/AKT/mTOR activation controls chemoprotective endothelial secretory responses.

    PubMed

    Bent, Eric H; Gilbert, Luke A; Hemann, Michael T

    2016-08-15

    Cancer therapy targets malignant cells that are surrounded by a diverse complement of nonmalignant stromal cells. Therapy-induced damage of normal cells can alter the tumor microenvironment, causing cellular senescence and activating cancer-promoting inflammation. However, how these damage responses are regulated (both induced and resolved) to preserve tissue homeostasis and prevent chronic inflammation is poorly understood. Here, we detail an acute chemotherapy-induced secretory response that is self-limiting in vitro and in vivo despite the induction of cellular senescence. We used tissue-specific knockout mice to demonstrate that endothelial production of the proinflammatory cytokine IL-6 promotes chemoresistance and show that the chemotherapeutic doxorubicin induces acute IL-6 release through reactive oxygen species-mediated p38 activation in vitro. Doxorubicin causes endothelial senescence but, surprisingly, without a typical senescence secretory response. We found that endothelial cells repress senescence-associated inflammation through the down-regulation of PI3K/AKT/mTOR signaling and that reactivation of this pathway restores senescence-associated inflammation. Thus, we describe a mechanism by which damage-associated paracrine secretory responses are restrained to preserve tissue homeostasis and prevent chronic inflammation. PMID:27566778

  20. Analytical study of STOL Aircraft in ground effect. Part 1: Nonplanar, nonlinear wing/jet lifting surface method

    NASA Technical Reports Server (NTRS)

    Shollenberger, C. A.; Smyth, D. N.

    1978-01-01

    A nonlinear, nonplanar three dimensional jet flap analysis, applicable to the ground effect problem, is presented. Lifting surface methodology is developed for a wing with arbitrary planform operating in an inviscid and incompressible fluid. The classical, infintely thin jet flap model is employed to simulate power induced effects. An iterative solution procedure is applied within the analysis to successively approximate the jet shape until a converged solution is obtained which closely satisfies jet and wing boundary conditions. Solution characteristics of the method are discussed and example results are presented for unpowered, basic powered and complex powered configurations. Comparisons between predictions of the present method and experimental measurements indicate that the improvement of the jet with the ground plane is important in the analyses of powered lift systems operating in ground proximity. Further development of the method is suggested in the areas of improved solution convergence, more realistic modeling of jet impingement and calculation efficiency enhancements.

  1. Resolving a Long-Standing Ambiguity: the Non-Planarity of gauche-1,3-BUTADIENE Revealed by Microwave Spectroscopy

    NASA Astrophysics Data System (ADS)

    Martin-Drumel, Marie-Aline; McCarthy, Michael C.; Patterson, David; Eibenberger, Sandra; Buckingham, Grant; Baraban, Joshua H.; Ellison, Barney; Stanton, John F.

    2016-06-01

    The preferred conformation of cis-1,3-butadiene (CH_2=CH-CH=CH_2) has been of long-standing importance in organic chemistry because of its role in Diels-Alder transition states. The molecule could adopt a planar s-cis conformation, in favor of conjugations in the carbon chain, or a non-planar gauche conformation, as a result of steric interactions between the terminal H atoms. To resolve this ambiguity, we have now measured the pure rotational spectrum of this isomer in the microwave region, unambiguously establishing a significant inertial defect, and therefore a gauche conformation. Experimental measurements of gauche-1,3-butadiene and several of its isotopologues using cavity Fourier-transform microwave (FTMW) spectroscopy in a supersonic expansion and chirped-pulse FTMW spectroscopy in a 4 K buffer gas cell will be summarized, as will new quantum chemical calculations.

  2. Vibrational spectra and molecular mechanics and ab initio calculations for 1,3-dioxole. Confirmation of non-planarity

    NASA Astrophysics Data System (ADS)

    Cortez, Enriqueta; Laane, Jaan

    1995-02-01

    Infrared and Raman spectra of the vapor, liquid, and solid phases of 1,3-dioxole have been recorded and analyzed. Much of the spectra can be interpreted assuming C2v symmetry. However, several combination bands with the ring-puckering vibration along with the observation of an otherwise inactive mode confirm the non-planarity of this molecule. The observed frequencies are compared with predicted values from molecular mechanics (MM3) and ab initio (STO3-21G∗) calculations. These calculated values provide useful estimates but about half of them differ from the observed values by more than 50 cm -1. Several predicted values disagree by more than 200 cm -1.

  3. Dynamics of non-planar vortices in the classical 2D anisotropic heisenberg model at finite temperatures

    NASA Astrophysics Data System (ADS)

    Kamppeter, T.; Mertens, F. G.; Sánchez, Angel; Gronbech-Jensen, N.; Bishop, A. R.; Dominguez-Adame, F.

    The 2-dimensional anisotropic Heisenberg model with XY- or easy-plane symmetry bears non-planar vortices which exhibit a localized structure of the z-components of the spins around the vortex center. In order to study the dynamics of these vortices under thermal fluctuations we use the Landau-Lifshitz equation and add white noise and Gilbert damping. Using a collective variable theory we derive an equation of motion with stochastic forces which are shown to represent white noise with an effective diffusion constant. We compare the results with Langevin dynamics simulations for the Landau-Lifshitz equation and find three temperature regimes: For low temperatures the dynamics is described by a 3rd-order equation of motion, for intermediate temperatures by a 1st-order equation. For higher temperatures, but still below the Kosterlitz-Thouless transition temperature, the spontaneous appearance of vortex-antivortex pairs does not allow a single-particle description.

  4. The effects of Bohm potential on ion-acoustic solitary waves interaction in a nonplanar quantum plasma

    NASA Astrophysics Data System (ADS)

    Li, Sheng-Chang

    2010-08-01

    The interaction of ion-acoustic solitary waves (IASWs) in a nonplanar unmagnetized quantum plasma consisting of electrons, positrons, and ions are studied by employing the quantum hydrodynamic model and the Korteweg-de Vries description. We provide the theoretical predictions about the phase shifts for the compressive IASWs and the rarefactive IASWs collisions, respectively. The effects of the positron to electron Fermi temperature ratio, the positron to ion number density ratio, and the quantum Bohm potential on phase shift are investigated. It is found that these factors can significantly modify the properties of the IASWs collisions. In particular, we find that the variations of phase shifts with quantum Bohm potential for two types of IASWs are apparently different. The validity of the results of present study is also pointed out.

  5. The non-uniform motion of arbitrary dislocation distributions by climb and by glide along non-planar paths

    NASA Astrophysics Data System (ADS)

    Brock, L. M.

    A S A BASIS for obtaining insight into both plastic flow in terms of dislocation motion and dynamic crack extension, the general problem of non-uniform motion of largely arbitrary dislocation distributions by climb and by glide along non-planar paths is considered. An exact solution is found in two forms: one form, vectorial in nature, shows that the essential distribution and path properties are contained in a symmetric tensor. The other form, consisting of complex functions, shows that the solution involves the inner product of the displacement discontinuity vector and complex vectors whose components normal and tangential to the path contour are related through tangent angle derivatives. Both forms illustrate that the solution has two components, one arising from the velocity discontinuity along the contour, the other arising from the displacement discontinuity at its edge and the edge speed.

  6. The influence of non-planar geometry on the flow within a distal end-to-side anastomosis

    NASA Astrophysics Data System (ADS)

    Sherwin, S. J.; Doorly, D. J.; Peiro, J.; Caro, C. G.

    1998-11-01

    The pattern of the flow in arteries is strongly influenced by the three-dimensional shape of the geometry. Curvature and torsion of the wall geometry alters the axial velocity distribution, and introduces cross flow velocity components. In this investigation we have considered flow in a model geometry of a fully occluded 45^o distal end-to-side anastomosis. Previous investigations have typically focused on planar end-to-side anastomoses where the bypass and host vessels have a plane of symmetry. We have increased the complexity of the model by considering a non-planar geometry produced by deforming the bypass vessel out of the plane of symmetry. The flows have been numerically and experimentally investigated using a spectral/hp element algorithm and magnetic resonance imaging. The significant effect of the non-planar geometry is to introduce a bulk rotation of the two secondary flow cells present in flow within a planar geometry. A reduction in wall shear stress is observed at the bed of the anastomosis and a larger absolute flux of velocity is seen within the occluded region proximal to the anastomosis. Current investigations have considered the role of pulsatility in the form of a non-reversing sinusoidal oscillation. In this case a separation bubble, not present in the steady case, is seen at the toe of the anastomosis during the systolic part of the cycle. The role of geometry and pulsatility on particle motion has also been addressed with a view to determining the shear exposure on particle within these types of flows.

  7. Amelogenins as Potential Buffers during Secretory-stage Amelogenesis

    PubMed Central

    Guo, J.; Lyaruu, D.M.; Takano, Y.; Gibson, C.W.; DenBesten, P.K.

    2015-01-01

    Amelogenins are the most abundant protein species in forming dental enamel, taken to regulate crystal shape and crystal growth. Unprotonated amelogenins can bind protons, suggesting that amelogenins could regulate the pH in enamel in situ. We hypothesized that without amelogenins the enamel would acidify unless ameloblasts were buffered by alternative ways. To investigate this, we measured the mineral and chloride content in incisor enamel of amelogenin-knockout (AmelX-/-) mice and determined the pH of enamel by staining with methyl-red. Ameloblasts were immunostained for anion exchanger-2 (Ae2), a transmembrane pH regulator sensitive for acid that secretes bicarbonate in exchange for chloride. The enamel of AmelX-/- mice was 10-fold thinner, mineralized in the secretory stage 1.8-fold more than wild-type enamel and containing less chloride (suggesting more bicarbonate secretion). Enamel of AmelX-/- mice stained with methyl-red contained no acidic bands in the maturation stage as seen in wild-type enamel. Secretory ameloblasts of AmelX-/- mice, but not wild-type mice, were immunopositive for Ae2, and stained more intensely in the maturation stage compared with wild-type mice. Exposure of AmelX-/- mice to fluoride enhanced the mineral content in the secretory stage, lowered chloride, and intensified Ae2 immunostaining in the enamel organ in comparison with non-fluorotic mutant teeth. The results suggest that unprotonated amelogenins may regulate the pH of forming enamel in situ. Without amelogenins, Ae2 could compensate for the pH drop associated with crystal formation. PMID:25535204

  8. Secretory immunity with special reference to the oral cavity

    PubMed Central

    Brandtzaeg, Per

    2013-01-01

    The two principal antibody classes present in saliva are secretory IgA (SIgA) and IgG; the former is produced as dimeric IgA by local plasma cells (PCs) in the stroma of salivary glands and is transported through secretory epithelia by the polymeric Ig receptor (pIgR), also named membrane secretory component (SC). Most IgG in saliva is derived from the blood circulation by passive leakage mainly via gingival crevicular epithelium, although some may be locally produced in the gingiva or salivary glands. Gut-associated lymphoid tissue (GALT) and nasopharynx-associated lymphoid tissue (NALT) do not contribute equally to the pool of memory/effector B cells differentiating to mucosal PCs throughout the body. Thus, enteric immunostimulation may not be the best way to activate the production of salivary IgA antibodies although the level of specific SIgA in saliva may still reflect an intestinal immune response after enteric immunization. It remains unknown whether the IgA response in submandibular/sublingual glands is better related to B-cell induction in GALT than the parotid response. Such disparity is suggested by the levels of IgA in submandibular secretions of AIDS patients, paralleling their highly upregulated intestinal IgA system, while the parotid IgA level is decreased. Parotid SIgA could more consistently be linked to immune induction in palatine tonsils/adenoids (human NALT) and cervical lymph nodes, as supported by the homing molecule profile observed after immune induction at these sites. Several other variables influence the levels of antibodies in salivary secretions. These include difficulties with reproducibility and standardization of immunoassays, the impact of flow rate, acute or chronic stress, protein loss during sample handling, and uncontrolled admixture of serum-derived IgG and monomeric IgA. Despite these problems, saliva is an easily accessible biological fluid with interesting scientific and clinical potentials. PMID:23487566

  9. Orchestration of secretory protein folding by ER chaperones

    PubMed Central

    Gidalevitz, Tali; Stevens, Fred; Argon, Yair

    2013-01-01

    The endoplasmic reticulum is a major compartment of protein biogenesis in the cell, dedicated to production of secretory, membrane and organelle proteins. The secretome has distinct structural and post-translational characteristics, since folding in the ER occurs in an environment that is distinct in terms of its ionic composition, dynamics and requirements for quality contol. The folding machinery in the ER therefore includes chaperones and folding enzymes that introduce, monitor and react to disulfide bonds, glycans, and fluctuations of luminal calcium. We describe the major chaperone networks in the lumen and discuss how they have distinct modes of operation that enable cells to accomplish highly efficient production of the secretome. PMID:23507200

  10. Calcium dynamics in the secretory granules of neuroendocrine cells.

    PubMed

    Alvarez, Javier

    2012-01-01

    Cellular Ca(2+)signaling results from a complex interplay among a variety of Ca(2+) fluxes going across the plasma membrane and across the membranes of several organelles, together with the buffering effect of large numbers of Ca(2+)-binding sites distributed along the cell architecture. Endoplasmic and sarcoplasmic reticulum, mitochondria and even nucleus have all been involved in cellular Ca(2+) signaling, and the mechanisms for Ca(2+) uptake and release from these organelles are well known. In neuroendocrine cells, the secretory granules also constitute a very important Ca(2+)-storing organelle, and the possible role of the stored Ca(2+) as a trigger for secretion has attracted considerable attention. However, this possibility is frequently overlooked, and the main reason for that is that there is still considerable uncertainty on the main questions related with granular Ca(2+) dynamics, e.g., the free granular [Ca(2+)], the physical state of the stored Ca(2+) or the mechanisms for Ca(2+) accumulation and release from the granules. This review will give a critical overview of the present state of knowledge and the main conflicting points on secretory granule Ca(2+) homeostasis in neuroendocrine cells.

  11. Widespread occurrence of expressed fungal secretory peroxidases in forest soils.

    PubMed

    Kellner, Harald; Luis, Patricia; Pecyna, Marek J; Barbi, Florian; Kapturska, Danuta; Krüger, Dirk; Zak, Donald R; Marmeisse, Roland; Vandenbol, Micheline; Hofrichter, Martin

    2014-01-01

    Fungal secretory peroxidases mediate fundamental ecological functions in the conversion and degradation of plant biomass. Many of these enzymes have strong oxidizing activities towards aromatic compounds and are involved in the degradation of plant cell wall (lignin) and humus. They comprise three major groups: class II peroxidases (including lignin peroxidase, manganese peroxidase, versatile peroxidase and generic peroxidase), dye-decolorizing peroxidases, and heme-thiolate peroxidases (e.g. unspecific/aromatic peroxygenase, chloroperoxidase). Here, we have repeatedly observed a widespread expression of all major peroxidase groups in leaf and needle litter across a range of forest ecosystems (e.g. Fagus, Picea, Acer, Quercus, and Populus spp.), which are widespread in Europe and North America. Manganese peroxidases and unspecific peroxygenases were found expressed in all nine investigated forest sites, and dye-decolorizing peroxidases were observed in five of the nine sites, thereby indicating biological significance of these enzymes for fungal physiology and ecosystem processes. Transcripts of selected secretory peroxidase genes were also analyzed in pure cultures of several litter-decomposing species and other fungi. Using this information, we were able to match, in environmental litter samples, two manganese peroxidase sequences to Mycena galopus and Mycena epipterygia and one unspecific peroxygenase transcript to Mycena galopus, suggesting an important role of this litter- and coarse woody debris-dwelling genus in the disintegration and transformation of litter aromatics and organic matter formation.

  12. Auxilin facilitates membrane traffic in the early secretory pathway.

    PubMed

    Ding, Jingzhen; Segarra, Verónica A; Chen, Shuliang; Cai, Huaqing; Lemmon, Sandra K; Ferro-Novick, Susan

    2016-01-01

    Coat protein complexes contain an inner shell that sorts cargo and an outer shell that helps deform the membrane to give the vesicle its shape. There are three major types of coated vesicles in the cell: COPII, COPI, and clathrin. The COPII coat complex facilitates vesicle budding from the endoplasmic reticulum (ER), while the COPI coat complex performs an analogous function in the Golgi. Clathrin-coated vesicles mediate traffic from the cell surface and between the trans-Golgi and endosome. While the assembly and structure of these coat complexes has been extensively studied, the disassembly of COPII and COPI coats from membranes is less well understood. We describe a proteomic and genetic approach that connects the J-domain chaperone auxilin, which uncoats clathrin-coated vesicles, to COPII and COPI coat complexes. Consistent with a functional role for auxilin in the early secretory pathway, auxilin binds to COPII and COPI coat subunits. Furthermore, ER-Golgi and intra-Golgi traffic is delayed at 15°C in swa2Δ mutant cells, which lack auxilin. In the case of COPII vesicles, we link this delay to a defect in vesicle fusion. We propose that auxilin acts as a chaperone and/or uncoating factor for transport vesicles that act in the early secretory pathway.

  13. Secretory immunity and the bacterial IgA proteases.

    PubMed

    Kornfeld, S J; Plaut, A G

    1981-01-01

    The characteristics and functions of microbial IgA proteases are reviewed. These enzymes represent a structurally heterogeneous group of proteins that are secreted into the extracellular environment by bacteria capable of causing human disease. The IgA proteases, which vary in their requirements for metal ions, are neutral endopeptidases whose role in the infectious process is not known but whose pronounced substrate specificity for human proteins of the IgA1 subclass has repeatedly been demonstrated. As reagents, the IgA proteases are useful in cleaving IgA molecules to yield intact Fc alpha and Fab alpha fragments that will allow the study of the structure and function of the two large regions of IgA immunoglobulin proteins. The role, if any, of these enzymes in promoting infection by pathogenic members of the genera Neisseria, Hemophilus, and Streptococcus is not known, although the secretory immune system is primarily mediated by antibodies of the IgA isotype, among which are IgA1 subclass proteins, and these proteins are susceptible to cleavage by IgA protease. The determination of the role of these enzymes in the pathogenesis of human infection must await clearer understanding of antigenicity and antibody function at secretory sites and of the relative roles of the two subclasses of human IgA in immune defense.

  14. Acid-induced secretory cell metaplasia in hamster bronchi

    SciTech Connect

    Christensen, T.G.; Lucey, E.C.; Breuer, R.; Snider, G.L.

    1988-02-01

    Hamsters were exposed to an intratracheal instillation of 0.5 ml of 0.08 N nitric, hydrochloric, or sulfuric acid to determine their airway epithelial response. Three weeks after exposure, the left intrapulmonary bronchi in Alcian blue/PAS-strained paraffin sections were evaluated for the amount of secretory product in the airway epithelium as a measure of secretory cell metaplasia (SCM). Compared to saline-treated control animals, all three acids caused statistically significant SCM. In addition to the bronchial lesion, all three acids caused similar interstitial fibrosis, bronchiolectasis, and bronchiolization of alveoli that varied in individual animals from mild to severe. In a separate experiment to study the persistence of the SCM, hamsters treated with a single instillation of 0.1 N nitric acid showed significant SCM 3, 7, and 17 weeks after exposure. There was a high correlation (r = 0.96) between a subjective assessment of SCM and objective assessment using a digital image-analysis system. We conclude that protons induce SCM independently of the associated anion; the SCM persists at least 17 weeks. Sulfuric acid is an atmospheric pollutant and nitric acid may form locally on the mucosa of lungs exposed to nitrogen dioxide. These acids may contribute to the development of maintenance of the SCM seen in the conducting airways of humans with chronic obstructive pulmonary disease.

  15. Widespread Occurrence of Expressed Fungal Secretory Peroxidases in Forest Soils

    PubMed Central

    Kellner, Harald; Luis, Patricia; Pecyna, Marek J.; Barbi, Florian; Kapturska, Danuta; Krüger, Dirk; Zak, Donald R.; Marmeisse, Roland; Vandenbol, Micheline; Hofrichter, Martin

    2014-01-01

    Fungal secretory peroxidases mediate fundamental ecological functions in the conversion and degradation of plant biomass. Many of these enzymes have strong oxidizing activities towards aromatic compounds and are involved in the degradation of plant cell wall (lignin) and humus. They comprise three major groups: class II peroxidases (including lignin peroxidase, manganese peroxidase, versatile peroxidase and generic peroxidase), dye-decolorizing peroxidases, and heme-thiolate peroxidases (e.g. unspecific/aromatic peroxygenase, chloroperoxidase). Here, we have repeatedly observed a widespread expression of all major peroxidase groups in leaf and needle litter across a range of forest ecosystems (e.g. Fagus, Picea, Acer, Quercus, and Populus spp.), which are widespread in Europe and North America. Manganese peroxidases and unspecific peroxygenases were found expressed in all nine investigated forest sites, and dye-decolorizing peroxidases were observed in five of the nine sites, thereby indicating biological significance of these enzymes for fungal physiology and ecosystem processes. Transcripts of selected secretory peroxidase genes were also analyzed in pure cultures of several litter-decomposing species and other fungi. Using this information, we were able to match, in environmental litter samples, two manganese peroxidase sequences to Mycena galopus and Mycena epipterygia and one unspecific peroxygenase transcript to Mycena galopus, suggesting an important role of this litter- and coarse woody debris-dwelling genus in the disintegration and transformation of litter aromatics and organic matter formation. PMID:24763280

  16. Characterization of a Secretory Annexin in Echinococcus granulosus.

    PubMed

    Song, Xingju; Hu, Dandan; Zhong, Xiuqin; Wang, Ning; Gu, Xiaobin; Wang, Tao; Peng, Xuerong; Yang, Guangyou

    2016-03-01

    Cystic echinococcosis, caused by Echinococcus granulosus, is a widespread parasitic zoonosis causing economic loss and public health problems. Annexins are important proteins usually present in the plasma membrane, but previous studies have shown that an annexin B33 protein of E. granulosus (Eg-ANX) could be detected in the excretory/secretory products and cyst fluid. In this study, we cloned and characterized Eg-ANX. In silico analysis showed that the amino acid sequence of Eg-ANX was conserved and lacked any signal peptides. The phospholipid-binding activity of recombinant Eg-ANX (rEg-ANX) was tested; liposomes could bind to rEg-ANX only in the presence of Ca(2+). In addition, we performed western blotting and immunohistochemical analyses to further validate the secretory properties of Eg-ANX. The protein could be detected in the cyst fluid of E. granulosus and was also present in the intermediate host tissues, which suggested that Eg-ANX might play an important role in parasite-host interaction.

  17. Aging and secretory reserve capacity of major salivary glands.

    PubMed

    Ghezzi, E M; Ship, J A

    2003-10-01

    A loss of acinar cells occurs with aging, while salivary production remains age-stable in healthy adults. It is hypothesized that a secretory reserve exists to preserve function despite a loss of acinar cells in normal aging. The purpose of this double-blind, placebo-controlled, crossover study was to determine age-related differences in salivary response to an anti-sialogogue (glycopyrrolate). Thirty-six healthy subjects (18 young--20-38 yrs; 18 older--60-77 yrs) received 4.0 microg/kg i.v. glycopyrrolate. Parotid and submandibular/sublingual saliva samples and xerostomia questionnaire responses were collected. Variables calculated for each subject were: times to initial and maximum suppression and xerostomic complaint; time to recovery; and durations of suppression and complaint. Salivary function was more adversely affected in older persons. There were no consistent age-associated questionnaire response differences. These findings suggest that salivary gland output is more adversely affected by an anti-sialogogue in healthy older vs. younger adults, supporting the secretory reserve hypothesis of salivary function. PMID:14514768

  18. Salivary Secretory Disorders, Inducing Drugs, and Clinical Management

    PubMed Central

    Miranda-Rius, Jaume; Brunet-Llobet, Lluís; Lahor-Soler, Eduard; Farré, Magí

    2015-01-01

    Background: Salivary secretory disorders can be the result of a wide range of factors. Their prevalence and negative effects on the patient's quality of life oblige the clinician to confront the issue. Aim: To review the salivary secretory disorders, inducing drugs and their clinical management. Methods: In this article, a literature search of these dysfunctions was conducted with the assistance of a research librarian in the MEDLINE/PubMed Database. Results: Xerostomia, or dry mouth syndrome, can be caused by medication, systemic diseases such as Sjögren's Syndrome, glandular pathologies, and radiotherapy of the head and neck. Treatment of dry mouth is aimed at both minimizing its symptoms and preventing oral complications with the employment of sialogogues and topical acting substances. Sialorrhea and drooling, are mainly due to medication or neurological systemic disease. There are various therapeutic, pharmacologic, and surgical alternatives for its management. The pharmacology of most of the substances employed for the treatment of salivary disorders is well-known. Nevertheless, in some cases a significant improvement in salivary function has not been observed after their administration. Conclusion: At present, there are numerous frequently prescribed drugs whose unwanted effects include some kind of salivary disorder. In addition, the differing pathologic mechanisms, and the great variety of existing treatments hinder the clinical management of these patients. The authors have designed an algorithm to facilitate the decision making process when physicians, oral surgeons, or dentists face these salivary dysfunctions. PMID:26516310

  19. Discovery and characterization of secretory IgD in rainbow trout: secretory IgD is produced through a novel splicing mechanism

    USGS Publications Warehouse

    Ramirez-Gomez, F.; Greene, W.; Rego, K.; Hansen, J.D.; Costa, G.; Kataria, P.; Bromage, E.S.

    2012-01-01

    The gene encoding IgH δ has been found in all species of teleosts studied to date. However, catfish (Ictalurus punctatus) is the only species of fish in which a secretory form of IgD has been characterized, and it occurs through the use of a dedicated δ-secretory exon, which is absent from all other species examined. Our studies have revealed that rainbow trout (Oncorhynchus mykiss) use a novel strategy for the generation of secreted IgD. The trout secretory δ transcript is produced via a run-on event in which the splice donor site at the end of the last constant domain exon (D7) is ignored and transcription continues until a stop codon is reached 33 nt downstream of the splice site, resulting in the production of an in-frame, 11-aa secretory tail at the end of the D7 domain. In silico analysis of several published IgD genes suggested that this unique splicing mechanism may also be used in other species of fish, reptiles, and amphibians. Alternative splicing of the secretory δ transcript resulted in two δ-H chains, which incorporated Cμ1 and variable domains. Secreted IgD was found in two heavily glycosylated isoforms, which are assembled as monomeric polypeptides associated with L chains. Secretory δ mRNA and IgD+ plasma cells were detected in all immune tissues at a lower frequency than secretory IgM. Our data demonstrate that secretory IgD is more prevalent and widespread across taxa than previously thought, and thus illustrate the potential that IgD may have a conserved role in immunity.

  20. 21 CFR 866.5380 - Free secretory component immuno-logical test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Free secretory component immuno-logical test system. 866.5380 Section 866.5380 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... Systems § 866.5380 Free secretory component immuno-logical test system. (a) Identification. A...

  1. Mammary analogue secretory carcinoma (MASC) of the salivary gland: A new tumor entity

    PubMed Central

    Damjanov, Ivan; Skenderi, Faruk; Vranic, Semir

    2016-01-01

    Mammary analogue secretory carcinoma (MASC) is a recently described low-grade malignant tumor of the salivary glands, biologically and morphologically equivalent to secretory breast carcinoma. We give a brief overview of this new entity, including morphological, immunohistochemical, molecular-genetic, clinical, epidemiologic features, differential diagnosis, and outcome results.

  2. The secretory pathway of protists: spatial and functional organization and evolution.

    PubMed Central

    Becker, B; Melkonian, M

    1996-01-01

    All cells secrete a diversity of macromolecules to modify their environment or to protect themselves. Eukaryotic cells have evolved a complex secretory pathway consisting of several membrane-bound compartments which contain specific sets of proteins. Experimental work on the secretory pathway has focused mainly on mammalian cell lines or on yeasts. Now, some general principles of the secretory pathway have become clear, and most components of the secretory pathway are conserved between yeast cells and mammalian cells. However, the structure and function of the secretory system in protists have been less extensively studied. In this review, we summarize the current knowledge about the secretory pathway of five different groups of protists: Giardia lamblia, one of the earliest lines of eukaryotic evolution, kinetoplastids, the slime mold Dictyostelium discoideum, and two lineages within the "crown" of eukaryotic cell evolution, the alveolates (ciliates and Plasmodium species) and the green algae. Comparison of these systems with the mammalian and yeast system shows that most elements of the secretory pathway were presumably present in the earliest eukaryotic organisms. However, one element of the secretory pathway shows considerable variation: the presence of a Golgi stack and the number of cisternae within a stack. We suggest that the functional separation of the plasma membrane from the nucleus-endoplasmic reticulum system during evolution required a sorting compartment, which became the Golgi apparatus. Once a Golgi apparatus was established, it was adapted to the various needs of the different organisms. PMID:8987360

  3. Mammary Analogue Secretory Carcinoma (MASC) of the salivary gland: A new tumor entity.

    PubMed

    Damjanov, Ivan; Skenderi, Faruk; Vranic, Semir

    2016-08-01

    Mammary analogue secretory carcinoma (MASC) is a recently described low-grade malignant tumor of the salivary glands, biologically and morphologically equivalent to secretory breast carcinoma. We give a brief overview of this new entity, including morphological, immunohistochemical, molecular-genetic, clinical, epidemiologic features, differential diagnosis, and outcome results. PMID:27483184

  4. The secretory pathway of protists: spatial and functional organization and evolution.

    PubMed

    Becker, B; Melkonian, M

    1996-12-01

    All cells secrete a diversity of macromolecules to modify their environment or to protect themselves. Eukaryotic cells have evolved a complex secretory pathway consisting of several membrane-bound compartments which contain specific sets of proteins. Experimental work on the secretory pathway has focused mainly on mammalian cell lines or on yeasts. Now, some general principles of the secretory pathway have become clear, and most components of the secretory pathway are conserved between yeast cells and mammalian cells. However, the structure and function of the secretory system in protists have been less extensively studied. In this review, we summarize the current knowledge about the secretory pathway of five different groups of protists: Giardia lamblia, one of the earliest lines of eukaryotic evolution, kinetoplastids, the slime mold Dictyostelium discoideum, and two lineages within the "crown" of eukaryotic cell evolution, the alveolates (ciliates and Plasmodium species) and the green algae. Comparison of these systems with the mammalian and yeast system shows that most elements of the secretory pathway were presumably present in the earliest eukaryotic organisms. However, one element of the secretory pathway shows considerable variation: the presence of a Golgi stack and the number of cisternae within a stack. We suggest that the functional separation of the plasma membrane from the nucleus-endoplasmic reticulum system during evolution required a sorting compartment, which became the Golgi apparatus. Once a Golgi apparatus was established, it was adapted to the various needs of the different organisms.

  5. Planar and nonplanar free-base tetraarylporphyrins: β-pyrrole substituents and geometric effects on electrochemistry, spectroelectrochemistry, and protonation/deprotonation reactions in nonaqueous media.

    PubMed

    Fang, Yuanyuan; Bhyrappa, P; Ou, Zhongping; Kadish, Karl M

    2014-01-01

    A series of planar and nonplanar free-base β-pyrrole substituted meso-tetraarylporphyrins were characterized by electrochemistry, spectroelectrochemistry, and protonation or deprotonation reactions in neutral, acidic, and basic solutions of CH2 Cl2 . The neutral compounds are represented as H2 (P), in which P represents a porphyrin dianion with one of several different sets of electron-withdrawing or -donating substituents at the messo and/or β-pyrrole positions of the macrocycle. The conversion of H2 (P) to [H4 (P)](2+) in CH2 Cl2 was accomplished by titration of the neutral porphyrin with trifluoroacetic acid (TFA) while the progress of the protonation was monitored by UV/Vis spectroscopy, which was also used to calculate logβ2 for proton addition to the core nitrogen atoms of the macrocycle. Cyclic voltammetry was performed after each addition of TFA or TBAOH to CH2 Cl2 solutions of the porphyrin and half-wave potentials for reduction were evaluated as a function of the added acid or base concentration. Thin-layer spectroelectrochemistry was used to obtain UV/Vis spectra of the neutral and protonated or deprotonated porphyrins under the application of an applied reducing potential. The magnitude of the protonation constants, the positions of λmax in the UV/Vis spectra and the half-wave or peak potentials for reduction are then related to the electronic properties of the porphyrin and the data evaluated as a function of the planarity or nonplanarity of the porphyrin macrocycle. Surprisingly, the electroreduction of the diprotonated nonplanar porphyrins in acid media leads to H2 (P), whereas the nonplanar H2 (P) derivatives are reduced to [(P)](2-) in CH2 Cl2 containing 0.1 M tetra-n-butylammonium perchlorate (TBAP). Thus, in both cases an electrochemically initiated deprotonation is observed.

  6. Development and Essential Oil Content of Secretory Glands of Sage (Salvia officinalis) 1

    PubMed Central

    Venkatachalam, K. V.; Kjonaas, Robert; Croteau, Rodney

    1984-01-01

    Scanning electron microscopy of sage (Salvia officinalis L.) leaves confirmed the presence of two basic types of glandular trichomes consisting of a capitate stalked form containing a multicellular stalk and surmounted by a unicellular secretory head, and a capitate sessile form containing a unicellular stalk and unicellular, or multicellular, secretory head. In the latter type, secretory activity and filling of the subcuticular cavity may begin at virtually any stage of the division cycle affording fully developed glands containing from one to twelve cells in the secretory head. Gas liquid chromatographic analysis of the oil content of the most numerous gland species (capitate stalked, capitate sessile with one and with eight secretory cells) indicated only minor quantitative differences in essential oil composition. Thus, each gland type is capable of producing the four major monoterpene families (p-menthanes, pinanes, bornanes and thujanes) characteristic of sage. Images Fig. 1 PMID:16663786

  7. Development and essential oil content of secretory glands of sage (Salvia officinalis)

    SciTech Connect

    Venkatachalam, K.V.; Kjonaas, R.; Croteau, R.

    1984-09-01

    Scanning electron microscopy of sage (Salvia officinalis L.) leave confirmed the presence of two basic types of glandular trichomes consisting of a capitate stalked form containing a multicellular stalk and surmounted by a unicellular secretory head, and a capitate sessile form containing a unicellular stalk and unicellular, or multicellular, secretory head. In the latter type, secretory activity and filling of the subcuticular cavity may begin at virtually any stage of the division cycle affording fully developed glands containing from one to twelve cells in the secretory head. Gas liquid chromatographic analysis of the oil content of the most numerous gland species (capitate stalked, capitate sessile with one and with eight secretory cells) indicated only minor quantitative differences in essential oil composition. Thus, each gland type is capable of producing the four major monoterpene families (p-menthanes, pinanes, bornanes and thujanes) characteristic of sage. 21 references, 2 figures.

  8. Development and Essential Oil Content of Secretory Glands of Sage (Salvia officinalis).

    PubMed

    Venkatachalam, K V; Kjonaas, R; Croteau, R

    1984-09-01

    Scanning electron microscopy of sage (Salvia officinalis L.) leaves confirmed the presence of two basic types of glandular trichomes consisting of a capitate stalked form containing a multicellular stalk and surmounted by a unicellular secretory head, and a capitate sessile form containing a unicellular stalk and unicellular, or multicellular, secretory head. In the latter type, secretory activity and filling of the subcuticular cavity may begin at virtually any stage of the division cycle affording fully developed glands containing from one to twelve cells in the secretory head. Gas liquid chromatographic analysis of the oil content of the most numerous gland species (capitate stalked, capitate sessile with one and with eight secretory cells) indicated only minor quantitative differences in essential oil composition. Thus, each gland type is capable of producing the four major monoterpene families (p-menthanes, pinanes, bornanes and thujanes) characteristic of sage. PMID:16663786

  9. The evolution of plant secretory structures and emergence of terpenoid chemical diversity.

    PubMed

    Lange, Bernd Markus

    2015-01-01

    Secretory structures in terrestrial plants appear to have first emerged as intracellular oil bodies in liverworts. In vascular plants, internal secretory structures, such as resin ducts and laticifers, are usually found in conjunction with vascular bundles, whereas subepidermal secretory cavities and epidermal glandular trichomes generally have more complex tissue distribution patterns. The primary function of plant secretory structures is related to defense responses, both constitutive and induced, against herbivores and pathogens. The ability to sequester secondary (or specialized) metabolites and defense proteins in secretory structures was a critical adaptation that shaped plant-herbivore and plant-pathogen interactions. Although this review places particular emphasis on describing the evolution of pathways leading to terpenoids, it also assesses the emergence of other metabolite classes to outline the metabolic capabilities of different plant lineages. PMID:25621517

  10. Fallopian tube secretory cell expansion: a sensitive biomarker for ovarian serous carcinogenesis

    PubMed Central

    Wang, Yiying; Li, Li; Wang, Yue; Tang, Sarah Ngocvi; Zheng, Wenxin

    2016-01-01

    Recent advances suggest that precancerous lesions of pelvic serous carcinoma originate from tubal secretory cells. The purpose of our study was to determine if an increased number of secretory cells vary with age or location in the fallopian tube and to examine its association with serous neoplasia. Three groups (benign control, high-risk, and pelvic serous carcinoma) of age-matched patients were studied. The age data were stratified into 10-year intervals ranging from 20-29 to older than 80. The number of secretory and ciliated cells from both tubal fimbria and ampulla segments was counted by microscopy and immunohistochemical staining methods. The data were analyzed by standard contingency table and Poisson distribution methods after age justification. We found that the absolute number of tubal secretory cells increased significantly with age in all three groups. But a more dramatic increase of secretory cells was observed in high-risk and pelvic serous carcinoma patients. Secretory cell expansion is more prevalent than secretory cell outgrowth in both fimbria and ampulla tubal segments and is significantly associated with serous neoplasia (p < 0.001). Furthermore, age remained a significant risk factor for serous neoplasia after age adjustment. These findings suggest that secretory cell expansion could serve as a potential sensitive biomarker for early serous carcinogenesis within the fallopian tube. The study also supports a relationship between serous neoplasia and increased secretory to ciliated cell ratios, and the relationship between frequency of secretory cell expansion within the fallopian tube and increasing age and-more significantly-presence of high-risk factors or co-existing serous cancers. PMID:27069556

  11. Secretory IgA: Arresting Microbial Pathogens at Epithelial Borders

    PubMed Central

    Mantis, Nicholas J.; Forbes, Stephen J.

    2013-01-01

    Secretory IgA (SIgA), the predominant class of antibody found in intestinal secretions. While SIgA’s role in protecting the intestinal epithelium from the enteric pathogen and toxins has long been recognized, surprisingly little is known about the molecular mechanisms by which this is achieved. The present review summarizes the current understanding of how SIgA functions to prevent microbial pathogens and toxins from gaining access to the intestinal epithelium. We also discuss recent work from our laboratory examining the interaction of a particular protective monoclonal IgA with Salmonella and propose, based on this work, that SIgA has a previously unrecognized capacity to directly interfere with microbial virulence at mucosal surfaces. PMID:20450284

  12. Dynamin-2 Function and Dysfunction Along the Secretory Pathway

    PubMed Central

    González-Jamett, Arlek M.; Momboisse, Fanny; Haro-Acuña, Valentina; Bevilacqua, Jorge A.; Caviedes, Pablo; Cárdenas, Ana María

    2013-01-01

    Dynamin-2 is a ubiquitously expressed mechano-GTPase involved in different stages of the secretory pathway. Its most well-known function relates to the scission of nascent vesicles from the plasma membrane during endocytosis; however, it also participates in the formation of new vesicles from the Golgi network, vesicle trafficking, fusion processes and in the regulation of microtubule, and actin cytoskeleton dynamics. Over the last 8 years, more than 20 mutations in the dynamin-2 gene have been associated to two hereditary neuromuscular disorders: Charcot–Marie–Tooth neuropathy and centronuclear myopathy. Most of these mutations are grouped in the pleckstrin homology domain; however, there are no common mutations associated with both disorders, suggesting that they differently impact on dynamin-2 function in diverse tissues. In this review, we discuss the impact of these disease-related mutations on dynamin-2 function during vesicle trafficking and endocytotic processes. PMID:24065954

  13. Characterization of Mast Cell Secretory Granules and Their Cell Biology

    PubMed Central

    Azouz, Nurit Pereg; Hammel, Ilan

    2014-01-01

    Exocytosis and secretion of secretory granule (SG) contained inflammatory mediators is the primary mechanism by which mast cells exert their protective immune responses in host defense, as well as their pathological functions in allergic reactions and anaphylaxis. Despite their central role in mast cell function, the molecular mechanisms underlying the biogenesis and secretion of mast cell SGs remain largely unresolved. Early studies have established the lysosomal nature of the mast cell SGs and implicated SG homotypic fusion as an important step occurring during both their biogenesis and compound secretion. However, the molecular mechanisms that account for key features of this process largely remain to be defined. A novel high-resolution imaging based methodology allowed us to screen Rab GTPases for their phenotypic and functional impact and identify Rab networks that regulate mast cell secretion. This screen has identified Rab5 as a novel regulator of homotypic fusion of the mast cell SGs that thereby regulates their size and cargo composition. PMID:24988214

  14. Secretory expression of a heterologous nattokinase in Lactococcus lactis.

    PubMed

    Liang, Xiaobo; Zhang, Lixin; Zhong, Jin; Huan, Liandong

    2007-05-01

    Nattokinase has been reported as an oral health product for the prevention of atherosclerosis. We developed a novel strategy to express a nattokinase from Bacillus subtilis in a live delivery vehicle, Lactococcus lactis. Promoter P( nisZ) and signal peptide SP(Usp) were used for inducible and secretory expression of nattokinase in L. lactis. Western blotting analysis demonstrated that nattokinase was successfully expressed, and about 94% of the enzyme was secreted to the culture. The recombinant nattokinase showed potent fibrinolytic activity, equivalent to 41.7 urokinase units per milliliter culture. Expression and delivery of such a fibrinolytic enzyme in the food-grade vehicle L. lactis would facilitate the widespread application of nattokinase in the control and prevention of thrombosis diseases.

  15. Spontaneous decrease in gastric secretory response to humoral stimuli.

    PubMed

    Waterfall, W

    1969-11-22

    The gastric response to pentagastrin was studied over a period of seven months in a healthy 25-year-old man without symptoms or history of gastrointestinal disease. An abrupt impairment of the gastric response to several stimulants was observed one month after starting the tests. Periodic testing since that time has shown no reversion to the type of response seen during the initial period of testing. A second subject with proved chronic duodenal ulceration presented an identical change in pattern of gastric response to stimulants.This study suggests that such a variation in the response to gastric stimulation in a subject with a normal stomach should be borne in mind when interpreting results of gastric secretory studies.

  16. Secretory otitis media and phonology when starting school.

    PubMed

    Lous, J

    1990-01-01

    The relationship between previous middle ear disease, the presence of secretory otitis media, and phonology was investigated in 99% of a cohort of 387 unselected 7-year-old children from two Danish municipalities. All the pupils were tested with a phonological sentence repetition test called SITO, when starting school. The social and otological backgrounds were obtained from the parents. When using an analysis of variance, there was an association between phonology and tympanogram type in the better ear. No association with otological history or pure-tone screening was found. The correlation between tympanogram type and phonology was confirmed in a stepwise multiple regression analysis with nine possible confounding variables. In the statistical model, the tympanogram type could 'explain' 2-3% of the variation in phonology compared with the most important background variable, the social group of the mothers 'explaining' about 4-5% of the variation. About 15% of the variation could be 'explained' by the included variables.

  17. Silent reading and secretory otitis media in school children.

    PubMed

    Lous, J

    1993-01-01

    In an unselected cohort of 366 8-year-old children, the relationship between secretory otitis media and reading achievement was investigated. The children underwent 10 impedance audiometries and 5 pure tone audiometries during their first year at school. At the beginning of the second grade they all had a Silent Reading Word Test (OS-400). The background parameters were recorded by an interview with one of the parents. There was a significant but small correlation between type B tympanograms in the first grade and silent word reading. No association between silent reading score and otological history or pure tone screening was found. In a stepwise multiple regression model, 37% of the variance could be 'explained' by the included variables. The 'classroom factor' could 'explain' about 17% of the variance, followed by phonology at the start of school (6%), gender (5%), social group of the mother (4%), type B tympanogram (2%), absence from school (2%) and allergy (1%).

  18. Interaction of planar and nonplanar organic contaminants with coal fly ash: Effects of polar and nonpolar solvent solutions

    SciTech Connect

    Burgess, R.M.; Ryba, S.A.; Cantwell, M.G.; Gundersen, J.L.; Tien, R.; Perron, M.M.

    2006-08-15

    Coal fly ash has a very high sorption capacity for a variety of anthropogenic contaminants and has been used to cleanse wastewater of pollutants for approximately 40 years. Like other black carbons, the planar structure of the residual carbon in fly ash results in elevated affinities for planar organic contaminants, such as polycyclic aromatic hydrocarbons (PAHs) and some polychlorinated biphenyls (PCBs). The present study was performed to understand better the mechanisms affecting the strong interaction between planar contaminants and coal fly ash. The removal of 10 PCBs and 10 PAHs by several fly ashes and other sorbents was evaluated under different experimental conditions to highlight the intermolecular forces influencing adsorption. Varying fly ash concentration and solvent system composition indicated that dispersive interactions were most prevalent. For the PCBs, empirical results also were compared to molecular modeling estimates of the energy necessary for the PCB molecule to assume a planar conformation (PCe). The PCe levels ranged from 8 to 25 kcal/mol, depending on the degree of ortho-substituted chlorination of the PCB. A significant correlation between PCe and PCB removal from solution was observed for the fly ashes and activated carbon, whereas the nonplanar sorbent octadecyl (C{sub 18}) indicated no relationship. These findings demonstrate the strong interaction between black carbon fly ash and planar organic contaminants. Furthermore, as exemplified by the PCBs, these results show how this interaction is a function of a contaminant's ability to assume a planar conformation.

  19. Labeling technique for nonplanar surfaces based on the combination of a diffractive axilens with digital holography methods

    NASA Astrophysics Data System (ADS)

    Marin, Pablo; Lizana, Angel; Peinado, Alba; Mora-González, Miguel; Campos, Juan

    2015-05-01

    A technique based on a spatial light modulator is proposed for the labeling of nonplanar surfaces. This technique arises from the combination of a general method for generation of digital holograms with a diffractive axilens. Unlike existing methods in which hologram contrast critically decreases out of the focal plane, our proposed approach allows the system to increase the focus depth, resulting in enhanced hologram images out of the focal plane. Two existing methods for hologram generation are theoretically and experimentally compared in terms of efficiency and contrast: the iterative Fourier transform algorithm-based method and the random multiplexing of different lenses method. The most suitable one is selected for the implementation of the new axilens-based technique. Experimental results obtained with the axilens method provide a significant enhancement of the image quality of holograms obtained out of the focal plane when compared with an existing technique. The approach proposed in this manuscript may be of interest in industrial applications, where alphanumeric data must be registered on nonflat surfaces, as in the cases of beverage cans or bottles.

  20. Optical 3D Deformation Measurement Utilizing Non-planar Surface for the Development of an “Intelligent Tire”

    NASA Astrophysics Data System (ADS)

    Matsuzaki, Ryosuke; Hiraoka, Naoki; Todoroki, Akira; Mizutani, Yoshihiro

    Intelligent tires, also known as smart tires, are equipped with sensors to monitor the strain of the interior surface and the rolling radius of tire, and are expected to improve the reliability of tires and tire control systems such as anti-lock braking systems (ABS). However, the high stiffness of an attached sensor like a strain gauge causes sensors to debond from the tire rubber. In the present study, a novel optical method is used for the concurrent monitoring of in-plane strain and out-of-plane displacement (rolling radius) utilizing the non-planar surface of the monitoring object. The optical method enables noncontact measurement of strain distribution. The in-plane strain and out-of-plane displacement are calculated by using image processing with an image of the interior surface of a tire that is taken with a single CCD camera fixed on the wheel rim. This new monitoring system is applied to an aluminum beam and a commercially available radial tire. As a result, the monitoring system provides concurrent measurement of in-plane strain, out-of-plane displacement and tire pressure, and is shown to be an effective monitoring system for intelligent tires.

  1. Design, Analysis and Application of a Novel Test for Sheet Metal Forming Limits under Non-Planar Stress States

    NASA Astrophysics Data System (ADS)

    Allwood, Julian M.; Shouler, Daniel R.

    2011-05-01

    Recent work on incremental sheet forming processes has demonstrated that they induce non-planar stress states which give significantly increased forming limits. In previous work, we have extended the Marcinak-Kuczynski analysis for in-plane loading to include proportional loading with all six components of the stress tensor, and have represented the results as a generalised forming limit diagram. This paper proposes a first standardised test of forming limits under these conditions. A novel apparatus is constructed in which a sliding carriage can apply controllable compressive rolling, three-roll bending, or through thickness shearing to a sample undergoing uniaxial extension. Finite element analysis demonstrates the effect of this loading on deformation and details of equipment design are given. Initial trials are used to assess the repeatability of the tests and to confirm whether the strain states induced in the workpieces conform with finite element predictions. Tests to examine increases in formability under various loading conditions show greatly increased failure strains, but with some variability in results, and only partial agreement with analytical predictions.

  2. A two-scale time-dependent damage model based on non-planar growth of micro-cracks

    NASA Astrophysics Data System (ADS)

    François, Bertrand; Dascalu, Cristian

    2010-11-01

    This paper presents the theoretical developments and the numerical applications of a time-dependent damage law. This law is deduced from considerations at the micro-scale where non-planar growth of micro-cracks, following a subcritical propagation criterion, is assumed. The orientation of the crack growth is governed by the maximum energy release rate at the crack tips and the introduction of an equivalent straight crack. The passage from micro-scale to macro-scale is done through an asymptotic homogenization approach. The model is built in two steps. First, the effective coefficients are calculated at the micro-scale in finite periodical cells, with respect to the micro-cracks length and their orientation. Then, a subcritical damage law is developed in order to establish the evolution of damage. This damage law is obtained as a differential equation depending on the microscopic stress intensity factors, which are a priori calculated for different crack lengths and orientations. The developed model enables to reproduce not only the classical short-term stress-strain response of materials (in tension and compression) but also the long-term behavior encountering relaxation and creep effects. Numerical simulations show the ability of the developed model to reproduce this time-dependent damage response of materials.

  3. Sorting and storage during secretory granule biogenesis: looking backward and looking forward.

    PubMed Central

    Arvan, P; Castle, D

    1998-01-01

    Secretory granules are specialized intracellular organelles that serve as a storage pool for selected secretory products. The exocytosis of secretory granules is markedly amplified under physiologically stimulated conditions. While granules have been recognized as post-Golgi carriers for almost 40 years, the molecular mechanisms involved in their formation from the trans-Golgi network are only beginning to be defined. This review summarizes and evaluates current information about how secretory proteins are thought to be sorted for the regulated secretory pathway and how these activities are positioned with respect to other post-Golgi sorting events that must occur in parallel. In the first half of the review, the emerging role of immature secretory granules in protein sorting is highlighted. The second half of the review summarizes what is known about the composition of granule membranes. The numerous similarities and relatively limited differences identified between granule membranes and other vesicular carriers that convey products to and from the plasmalemma, serve as a basis for examining how granule membrane composition might be established and how its unique functions interface with general post-Golgi membrane traffic. Studies of granule formation in vitro offer additional new insights, but also important challenges for future efforts to understand how regulated secretory pathways are constructed and maintained. PMID:9620860

  4. Lipids implicated in the journey of a secretory granule: from biogenesis to fusion.

    PubMed

    Tanguy, Emeline; Carmon, Ophélie; Wang, Qili; Jeandel, Lydie; Chasserot-Golaz, Sylvette; Montero-Hadjadje, Maité; Vitale, Nicolas

    2016-06-01

    The regulated secretory pathway begins with the formation of secretory granules by budding from the Golgi apparatus and ends by their fusion with the plasma membrane leading to the release of their content into the extracellular space, generally following a rise in cytosolic calcium. Generation of these membrane-bound transport carriers can be classified into three steps: (i) cargo sorting that segregates the cargo from resident proteins of the Golgi apparatus, (ii) membrane budding that encloses the cargo and depends on the creation of appropriate membrane curvature, and (iii) membrane fission events allowing the nascent carrier to separate from the donor membrane. These secretory vesicles then mature as they are actively transported along microtubules toward the cortical actin network at the cell periphery. The final stage known as regulated exocytosis involves the docking and the priming of the mature granules, necessary for merging of vesicular and plasma membranes, and the subsequent partial or total release of the secretory vesicle content. Here, we review the latest evidence detailing the functional roles played by lipids during secretory granule biogenesis, recruitment, and exocytosis steps. In this review, we highlight evidence supporting the notion that lipids play important functions in secretory vesicle biogenesis, maturation, recruitment, and membrane fusion steps. These effects include regulating various protein distribution and activity, but also directly modulating membrane topology. The challenges ahead to understand the pleiotropic functions of lipids in a secretory granule's journey are also discussed. This article is part of a mini review series on Chromaffin cells (ISCCB Meeting, 2015).

  5. Transcriptional regulation of secretory capacity by bZip transcription factors

    PubMed Central

    FOX, Rebecca M.

    2015-01-01

    Cells of specialized secretory organs expand their secretory pathways to accommodate the increased protein load necessary for their function. The endoplasmic reticulum (ER), the Golgi apparatus and the secretory vesicles, expand not only the membrane components but also the protein machinery required for increased protein production and transport. Increased protein load causes an ER stress response akin to the Unfolded Protein Response (UPR). Recent work has implicated several bZip transcription factors in the regulation of protein components of the early secretory pathway necessary to alleviate this stress. Here, we highlight eight bZip transcription factors in regulating secretory pathway component genes. These include components of the three canonical branches of the UPR–ATF4, XBP1, and ATF6, as well as the five members of the Creb3 family of transcription factors. We review findings from both invertebrate and vertebrate model systems suggesting that all of these proteins increase secretory capacity in response to increased protein load. Finally, we propose that the Creb3 family of factors may have a dual role in secretory cell differentiation by also regulating the pathways necessary for cell cycle exit during terminal differentiation. PMID:25821458

  6. FTOM-2D: a two-dimensional approach to model the detailed thermal behavior of nonplanar surfaces

    NASA Astrophysics Data System (ADS)

    Bartos, B.; Stein, K.

    2015-10-01

    The Fraunhofer thermal object model (FTOM) predicts the temperature of an object as a function of the environmental conditions. The model has an outer layer exchanging radiation and heat with the environment and a stack of layers beyond modifying the thermal behavior. The innermost layer is at a constant or variable temperature called core temperature. The properties of the model (6 parameters) are fitted to minimize the difference between the prediction and a time series of measured temperatures. The model can be used for very different objects like backgrounds (e.g. meadow, forest, stone, or sand) or objects like vehicles. The two dimensional enhancement was developed to model more complex objects with non-planar surfaces and heat conduction between adjacent regions. In this model we call the small thermal homogenous interacting regions thermal pixels. For each thermal pixel the orientation and the identities of the adjacent pixels are stored in an array. In this version 7 parameters have to be fitted. The model is limited to a convex geometry to reduce the complexity of the heat exchange and allow for a higher number of thermal pixels. For the test of the model time series of thermal images of a test object (CUBI) were analyzed. The square sides of the cubes were modeled as 25 thermal pixels (5 × 5). In the time series of thermal images small areas in the size of the thermal pixels were analyzed to generate data files that can easily be read by the model. The program was developed with MATLAB and the final version in C++ using the OpenMP multiprocessor library. The differential equation for the heat transfer is the time consuming part in the computation and was programmed in C. The comparison show a good agreement of the fitted and not fitted thermal pixels with the measured temperatures. This indicates the ability of the model to predict the temperatures of the whole object.

  7. Excretion pattern of co-planar and non-planar tetra- and hexa-chlorobiphenyls in ovine milk and faeces

    SciTech Connect

    Vrecl, Milka . E-mail: milka.vrecl@vf.uni-lj.si; Ursic, Matjaz; Pogacnik, Azra; Zupancic-Kralj, Lucija; Jan, Janja

    2005-04-15

    This study employed the gas chromatography with electron capture detection to determine residual levels and excretion patterns of two pairs of structurally diverse polychlorinated biphenyl (PCB) congeners (IUPAC Nos. 54, 80, 155, and 169) administered to lactating sheep by intramuscular injection. PCB levels and excretion patterns in blood, milk, and faeces were time-dependent and differed from the composition of PCB congeners administered. Lactational transfer substantially exceeded the faecal transfer. Between days 3 and 7, the amount of PCB congeners 54 and 169 excreted in milk was around 50- and 800-fold higher than the amount of these two congeners excreted via faeces. During the same period, the relative contribution of co-planar PCB congeners (80 and 169) in PCB pattern decreased in blood and increased in milk and faeces compared with non-planar PCBs (54 and 155). On day 3, the ratio PCB 169 to 54 was 7-fold higher in milk than in faeces. PCB congeners with log K{sub ow} values under 6.5 reached peaks of their excretion in milk within the first three days after administration, while the super-lipophilic PCB 169 congener with log K{sub ow} value of over 7 has not reached the plateau until day 10, but afterwards, its level remained relatively high throughout the observation period. During the 57-day follow-up period, the excretion of PCB 80, 155, and 169 in milk was 4.5-, 14-, and 46-fold greater compared with PCB 54. Differences in levels and patterns were explained with some physico-chemical properties of individual PCB congeners, such as lipophilicity, planarity, metabolic stability, sorption/diffusion properties.

  8. Improvement of boundary conditions for non-planar boundaries represented by polygons with an initial particle arrangement technique

    NASA Astrophysics Data System (ADS)

    Zhang, Tiangang; Koshizuka, Seiichi; Murotani, Kohei; Shibata, Kazuya; Ishii, Eiji; Ishikawa, Masanori

    2016-02-01

    The boundary conditions represented by polygons in moving particle semi-implicit (MPS) method (Koshizuka and Oka, Nuclear Science and Engineering, 1996) have been widely used in the industry simulations since it can simply simulate complex geometry with high efficiency. However, the inaccurate particle number density near non-planar wall boundaries dramatically affects the accuracy of simulations. In this paper, we propose an initial boundary particle arrangement technique coupled with the wall weight function method (Zhang et al. Transaction of JSCES, 2015) to improve the particle number density near slopes and curved surfaces with boundary conditions represented by polygons in three dimensions. Two uniform grids are utilized in the proposed technique. The grid points in the first uniform grid are used to construct boundary particles, and the second uniform grid stores the same information as in the work by Zhang et al. The wall weight functions of the grid points in the second uniform grid are calculated by newly constructed boundary particles. The wall weight functions of the fluid particles are interpolated from the values stored on the grid points in the second uniform grid. Because boundary particles are located on the polygons, complex geometries can be accurately represented. The proposed method can dramatically improve the particle number density and maintain the high efficiency. The performance of the previously proposed wall weight function (Zhang et al.) with the boundary particle arrangement technique is verified in comparison with the wall weight function without boundary particle arrangement by investigating two example geometries. The simulations of a water tank with a wedge and a complex geometry show the general applicability of the boundary particle arrangement technique to complex geometries and demonstrate its improvement of the wall weight function near the slopes and curved surfaces.

  9. Detection of latent fingerprints using high-resolution 3D confocal microscopy in non-planar acquisition scenarios

    NASA Astrophysics Data System (ADS)

    Kirst, Stefan; Vielhauer, Claus

    2015-03-01

    In digitized forensics the support of investigators in any manner is one of the main goals. Using conservative lifting methods, the detection of traces is done manually. For non-destructive contactless methods, the necessity for detecting traces is obvious for further biometric analysis. High resolutional 3D confocal laser scanning microscopy (CLSM) grants the possibility for a detection by segmentation approach with improved detection results. Optimal scan results with CLSM are achieved on surfaces orthogonal to the sensor, which is not always possible due to environmental circumstances or the surface's shape. This introduces additional noise, outliers and a lack of contrast, making a detection of traces even harder. Prior work showed the possibility of determining angle-independent classification models for the detection of latent fingerprints (LFP). Enhancing this approach, we introduce a larger feature space containing a variety of statistical-, roughness-, color-, edge-directivity-, histogram-, Gabor-, gradient- and Tamura features based on raw data and gray-level co-occurrence matrices (GLCM) using high resolutional data. Our test set consists of eight different surfaces for the detection of LFP in four different acquisition angles with a total of 1920 single scans. For each surface and angles in steps of 10, we capture samples from five donors to introduce variance by a variety of sweat compositions and application influences such as pressure or differences in ridge thickness. By analyzing the present test set with our approach, we intend to determine angle- and substrate-dependent classification models to determine optimal surface specific acquisition setups and also classification models for a general detection purpose for both, angles and substrates. The results on overall models with classification rates up to 75.15% (kappa 0.50) already show a positive tendency regarding the usability of the proposed methods for LFP detection on varying surfaces in non-planar

  10. Mapping organelle motion reveals a vesicular conveyor belt spatially replenishing secretory vesicles in stimulated chromaffin cells.

    PubMed

    Maucort, Guillaume; Kasula, Ravikiran; Papadopulos, Andreas; Nieminen, Timo A; Rubinsztein-Dunlop, Halina; Meunier, Frederic A

    2014-01-01

    How neurosecretory cells spatially adjust their secretory vesicle pools to replenish those that have fused and released their hormonal content is currently unknown. Here we designed a novel set of image analyses to map the probability of tracked organelles undergoing a specific type of movement (free, caged or directed). We then applied our analysis to time-lapse z-stack confocal imaging of secretory vesicles from bovine Chromaffin cells to map the global changes in vesicle motion and directionality occurring upon secretagogue stimulation. We report a defined region abutting the cortical actin network that actively transports secretory vesicles and is dissipated by actin and microtubule depolymerizing drugs. The directionality of this "conveyor belt" towards the cell surface is activated by stimulation. Actin and microtubule networks therefore cooperatively probe the microenvironment to transport secretory vesicles to the periphery, providing a mechanism whereby cells globally adjust their vesicle pools in response to secretagogue stimulation. PMID:24489879

  11. Cytodiagnosis of secretory carcinoma of the breast: a report on two cases.

    PubMed

    Jena, Madhusmita; Shariff, Shameem

    2010-12-01

    Secretory carcinoma of the breast is a rare (<1%) low grade breast carcinoma which shows distinct features at histology. Diagnosis of this carcinoma at fine needle aspiration cytology (FNAC) is difficult. Two cases of secretory carcinoma of the breast presenting as a breast mass, one in a 24-year-old female and the other in a 40-year-old female are reported, highlighting their appearance at FNAC. In both the cases the aspirates were cellular and consisted of clusters and single cells with uniform round nuclei showing minimal nuclear atypia. Most of the cells had moderate to abundant cytoplasm with prominent intracytoplasmic vacuoles. Many cells showed a plasmacytoid appearance and others were binucleate. A typical amphophilic bubbly cytoplasm of the tumor cells was observed. Both cases were confirmed as secretory carcinoma on histology. The differences in cell morphology at FNAC of secretory carcinoma of the breast from other breast carcinomas, and its utility of making a preoperative diagnosis are discussed.

  12. Observing secretory granules with a multiangle evanescent wave microscope.

    PubMed Central

    Rohrbach, A

    2000-01-01

    In total internal reflection fluorescence microscopy (TIRFM), fluorophores near a surface can be excited with evanescent waves, which decay exponentially with distance from the interface. Penetration depths of evanescent waves from 60 nm to 300 nm were generated by varying the angle of incidence of a laser beam. With a novel telecentric multiangle evanescent wave microscope, we monitored and investigated both single secretory granules and pools of granules in bovine chromaffin cells. By measuring the fluorescence intensity as a function of penetration depth, it is possible through a Laplace transform to obtain the fluorophore distribution as a function of axial position. We discuss the extent to which it is possible to determine distances and diameters of granules with this microscopy technique by modeling the fluorescent volumes of spheres in evanescent fields. The anisotropic near-field detection of fluorophores and the influence of the detection point-spread function are considered. The diameters of isolated granules between 70 nm and 300 nm have been reconstructed, which is clearly beyond the resolution limit of a confocal microscope. Furthermore, the paper demonstrates how evanescent waves propagate along surfaces and scatter at objects with a higher refractive index. TIRFM will have a limited applicability for quantitative measurements when the parameters used to define evanescent waves are not optimally selected. PMID:10777760

  13. Mitochondrial Dysfunction Induces Senescence with a Distinct Secretory Phenotype.

    PubMed

    Wiley, Christopher D; Velarde, Michael C; Lecot, Pacome; Liu, Su; Sarnoski, Ethan A; Freund, Adam; Shirakawa, Kotaro; Lim, Hyung W; Davis, Sonnet S; Ramanathan, Arvind; Gerencser, Akos A; Verdin, Eric; Campisi, Judith

    2016-02-01

    Cellular senescence permanently arrests cell proliferation, often accompanied by a multi-faceted senescence-associated secretory phenotype (SASP). Loss of mitochondrial function can drive age-related declines in the function of many post-mitotic tissues, but little is known about how mitochondrial dysfunction affects mitotic tissues. We show here that several manipulations that compromise mitochondrial function in proliferating human cells induce a senescence growth arrest with a modified SASP that lacks the IL-1-dependent inflammatory arm. Cells that underwent mitochondrial dysfunction-associated senescence (MiDAS) had lower NAD+/NADH ratios, which caused both the growth arrest and prevented the IL-1-associated SASP through AMPK-mediated p53 activation. Progeroid mice that rapidly accrue mtDNA mutations accumulated senescent cells with a MiDAS SASP in vivo, which suppressed adipogenesis and stimulated keratinocyte differentiation in cell culture. Our data identify a distinct senescence response and provide a mechanism by which mitochondrial dysfunction can drive aging phenotypes. PMID:26686024

  14. Secretory phospholipase A2 in patients with coronary artery disease.

    PubMed

    Lima, Luciana Moreira; Carvalho, Maria das Graças; da Fonseca Neto, Cirilo Pereira; Garcia, José Carlos Faria; Sousa, Marinez Oliveira

    2010-04-01

    This study investigated the correlation of sPLA2 (secretory phospholipase A2) activity with the atheromatosis extent in subjects with coronary artery disease (CAD) undergoing coronary angiography. We analyzed 123 patients, including 35 subjects with angiographically normal coronary arteries (controls), 31 with mild/moderate atheromatosis (stenosis of 30-70% of the luminal diameter in one or more coronary arteries) and 57 with severe atheromatosis (>70% stenosis). Plasma sPLA2 activity was significantly higher in subjects with severe [127.7 U/ml (102.3-162.7); p < 0.0001] and mild/moderate [112.0 U/ml (100.6-146.9); p < 0.0001] atheromatosis than in controls [19.8 U/ml (15.1-32.1)]. In a multiple logistic regression model, adjusted for age, gender, body mass index, tabagism, hypertension, sedentarism, family history for coronary artery disease, diabetes mellitus, total cholesterol, HDLc, LDLc, triglycerides, high sensitivity C-reactive protein and phospholipase A2, only sPLA2 was observed to be independently associated with severe CAD (>70% of stenosis) (p < 0.0001). PMID:19449149

  15. Gut Microbial Succession Follows Acute Secretory Diarrhea in Humans

    PubMed Central

    David, Lawrence A.; Weil, Ana; Ryan, Edward T.; Calderwood, Stephen B.; Harris, Jason B.; Chowdhury, Fahima; Begum, Yasmin; Qadri, Firdausi

    2015-01-01

    ABSTRACT Disability after childhood diarrhea is an important burden on global productivity. Recent studies suggest that gut bacterial communities influence how humans recover from infectious diarrhea, but we still lack extensive data and mechanistic hypotheses for how these bacterial communities respond to diarrheal disease and its treatment. Here, we report that after Vibrio cholerae infection, the human gut microbiota undergoes an orderly and reproducible succession that features transient reversals in relative levels of enteric Bacteroides and Prevotella. Elements of this succession may be a common feature in microbiota recovery from acute secretory diarrhea, as we observed similar successional dynamics after enterotoxigenic Escherichia coli (ETEC) infection. Our metagenomic analyses suggest that multiple mechanisms drive microbial succession after cholera, including bacterial dispersal properties, changing enteric oxygen and carbohydrate levels, and phage dynamics. Thus, gut microbiota recovery after cholera may be predictable at the level of community structure but is driven by a complex set of temporally varying ecological processes. Our findings suggest opportunities for diagnostics and therapies targeting the gut microbiota in humans recovering from infectious diarrhea. PMID:25991682

  16. Role of NBCe1 and AE2 in Secretory Ameloblasts

    PubMed Central

    Paine, Michael L.; Snead, Malcolm L.; Wang, HongJun; Abuladze, Natalia; Pushkin, Alexander; Liu, Weixin; Kao, Li Yo; Wall, Susan M.; Kim, Young-Hee; Kurtz, Ira

    2008-01-01

    The H+/base transport processes that control the pH of the microenvironment adjacent to ameloblasts are not currently well understood. Mice null for the AE2 anion exchanger have abnormal enamel. In addition, patients with mutations in the electrogenic sodium bicarbonate cotransporter NBCe1 and mice lacking NBCe1 have enamel abnormalities. These observations suggest that AE2 and NBCe1 play important roles in amelogenesis. The present study aimed to understand the roles of AE2 and NBC1 in ameloblasts. The data showed that NBCe1 is expressed at the basolateral membrane of secretory ameloblasts, whereas AE2 is expressed at the apical membrane. Transcripts for AE2a and NBCe1-B were detected in RNA isolated from cultured ameloblast-like LS8 cells. Our data are the first evidence that AE2 and NBCe1 are expressed in ameloblasts in vivo in a polarized fashion thereby providing a mechanism for ameloblast transcellular bicarbonate secretion in the process of enamel formation and maturation. PMID:18362326

  17. Small molecules intercept Notch signaling and the early secretory pathway.

    PubMed

    Krämer, Andreas; Mentrup, Torben; Kleizen, Bertrand; Rivera-Milla, Eric; Reichenbach, Daniela; Enzensperger, Christoph; Nohl, Richard; Täuscher, Eric; Görls, Helmar; Ploubidou, Aspasia; Englert, Christoph; Werz, Oliver; Arndt, Hans-Dieter; Kaether, Christoph

    2013-11-01

    Notch signaling has a pivotal role in numerous cell-fate decisions, and its aberrant activity leads to developmental disorders and cancer. To identify molecules that influence Notch signaling, we screened nearly 17,000 compounds using automated microscopy to monitor the trafficking and processing of a ligand-independent Notch-enhanced GFP (eGFP) reporter. Characterization of hits in vitro by biochemical and cellular assays and in vivo using zebrafish led to five validated compounds, four of which induced accumulation of the reporter at the plasma membrane by inhibiting γ-secretase. One compound, the dihydropyridine FLI-06, disrupted the Golgi apparatus in a manner distinct from that of brefeldin A and golgicide A. FLI-06 inhibited general secretion at a step before exit from the endoplasmic reticulum (ER), which was accompanied by a tubule-to-sheet morphological transition of the ER, rendering FLI-06 the first small molecule acting at such an early stage in secretory traffic. These data highlight the power of phenotypic screening to enable investigations of central cellular signaling pathways. PMID:24077179

  18. Secretory immunity in defense against cariogenic mutans streptococci.

    PubMed

    Russell, M W; Hajishengallis, G; Childers, N K; Michalek, S M

    1999-01-01

    Specific immune defense against cariogenic mutans streptococci is provided largely by salivary secretory IgA antibodies, which are generated by the common mucosal immune system. This system is functional in newborn infants, who develop salivary IgA antibodies as they become colonized by oral microorganisms. The mechanisms of action of salivary IgA antibodies include interference with sucrose-independent and sucrose- dependent attachment of mutans streptococci to tooth surfaces, as well as possible inhibition of metabolic activities. The goal of protecting infants against colonization by mutans streptococci might be accomplished by applying new strategies of mucosal immunization that would induce salivary IgA antibodies without the complications of parenteral immunization. Strategies of mucosal immunization against mutans streptococci currently under development include the use of surface adhesins and glucosyltransferase as key antigens, which are being incorporated into novel mucosal vaccine delivery systems and adjuvants. The oral application of preformed, genetically engineered antibodies to mutans streptococcal antigens also offers new prospects for passive immunization against dental caries. PMID:9831775

  19. Secretory phospholipase A2 induces dendritic cell maturation

    PubMed Central

    Perrin-Cocon, Laure; Agaugué, Sophie; Coutant, Frédéric; Masurel, Aurélie; Bezzine, Sofiane; Lambeau, Gérard; André, Patrice; Lotteau, Vincent

    2004-01-01

    High level of phospholipase A2 (PLA2) activity is found in serum and biological fluids during the acute phase response (APR). Extracellular PLA2 in fluids of patients with inflammatory diseases such as sepsis, acute pancreatitis or rheumatoid arthritis is also associated with propagation of inflammation. PLA2 activity is involved in the release of both pro- and anti-inflammatory lipid mediators from phospholipids of cellular membranes or circulating lipoproteins. PLA2 may thus generate signals that influence immune responses. Here, group III secretory PLA2s were tested for their ability to promote generation of functionally mature human dendritic cells (DC). PLA2 treatment of differentiating monocytes in the presence of GM-CSF and IL-4 yielded cells with phenotypical and functional characteristics of mature DC. This maturation was dependent on the dose of PLA2 and PLA2-generated DC stimulated interferon gamma secretion by allogeneic T cells. The effects of PLA2 on DC maturation was mainly dependent on enzyme activity and correlated with the activation of NF-κB, AP-1 and NFAT. The data suggest that transient increase in PLA2 activity generates signals that promote transition of innate to adaptive immunity during the APR. PMID:15259027

  20. The complete general secretory pathway in gram-negative bacteria.

    PubMed Central

    Pugsley, A P

    1993-01-01

    The unifying feature of all proteins that are transported out of the cytoplasm of gram-negative bacteria by the general secretory pathway (GSP) is the presence of a long stretch of predominantly hydrophobic amino acids, the signal sequence. The interaction between signal sequence-bearing proteins and the cytoplasmic membrane may be a spontaneous event driven by the electrochemical energy potential across the cytoplasmic membrane, leading to membrane integration. The translocation of large, hydrophilic polypeptide segments to the periplasmic side of this membrane almost always requires at least six different proteins encoded by the sec genes and is dependent on both ATP hydrolysis and the electrochemical energy potential. Signal peptidases process precursors with a single, amino-terminal signal sequence, allowing them to be released into the periplasm, where they may remain or whence they may be inserted into the outer membrane. Selected proteins may also be transported across this membrane for assembly into cell surface appendages or for release into the extracellular medium. Many bacteria secrete a variety of structurally different proteins by a common pathway, referred to here as the main terminal branch of the GSP. This recently discovered branch pathway comprises at least 14 gene products. Other, simpler terminal branches of the GSP are also used by gram-negative bacteria to secrete a more limited range of extracellular proteins. PMID:8096622

  1. Characterization of excretory/secretory antigen from Toxocara vitulorum larvae.

    PubMed

    Starke-Buzetti, Wilma A; Ferreira, Fabiano P

    2004-10-01

    Toxocara vitulorum is a nematode parasite of the small intestine of cattle and water buffalo, particularly buffalo calves between one and three months of age, causing high morbidity and mortality. The purpose of this research was to characterize the excretory/secretory (ES) antigens of T. vitulorum larvae by SDS-polyacrylamide gel electrophoresis (PAGE) and Western blot (WB), using immune sera and colostrum of buffalo naturally infected by T. vitulorum. The parasitological status of the buffalo calves was also evaluated using sequential fecal examinations. The results showed that the ES antigen revealed eight (190, 150, 110, 90, 64, 56, 48, and 19 kDa) protein bands by SDS-PAGE. The majority of these bands were recognized in the sera and colostrum of infected buffalo with T. vitulorum when analyzed by WB. However, particularly fractions of high molecular weight (190, 150, 110, and 90 kDa) were represented in more prominent bands and persisted in the groups of buffalo calves at the peak of egg output, as well as during the period of rejection of T. vitulorum by the feces of the calves. During the period of post-rejection of the worms (between the day 118 and 210 of age) the serum antibodies did not react with any protein bands. On the other hand, sera from buffalo calves at one day of age (after suckling the colostrum and at the beginning of infection) reacted with the same bands detected in the serum and colostrum of the buffalo cows.

  2. Bayesian Estimation of 3D Non-planar Fault Geometry and Slip: An application to the 2011 Megathrust (Mw 9.1) Tohoku-Oki Earthquake

    NASA Astrophysics Data System (ADS)

    Dutta, Rishabh; Jónsson, Sigurjón

    2016-04-01

    Earthquake faults are generally considered planar (or of other simple geometry) in earthquake source parameter estimations. However, simplistic fault geometries likely result in biases in estimated slip distributions and increased fault slip uncertainties. In case of large subduction zone earthquakes, these biases and uncertainties propagate into tsunami waveform modeling and other calculations related to postseismic studies, Coulomb failure stresses, etc. In this research, we parameterize 3D non-planar fault geometry for the 2011 Tohoku-Oki earthquake (Mw 9.1) and estimate these geometrical parameters along with fault slip parameters from onland and offshore GPS using Bayesian inference. This non-planar fault is formed using several 3rd degree polynomials in along-strike (X-Y plane) and along-dip (X-Z plane) directions that are tied together using a triangular mesh. The coefficients of these polynomials constitute the fault geometrical parameters. We use the trench and locations of past seismicity as a priori information to constrain these fault geometrical parameters and the Laplacian to characterize the fault slip smoothness. Hyper-parameters associated to these a priori constraints are estimated empirically and the posterior probability distribution of the model (fault geometry and slip) parameters is sampled using an adaptive Metropolis Hastings algorithm. The across-strike uncertainties in the fault geometry (effectively the local fault location) around high-slip patches increases from 6 km at 10km depth to about 35 km at 50km depth, whereas around low-slip patches the uncertainties are larger (from 7 km to 70 km). Uncertainties in reverse slip are found to be higher at high slip patches than at low slip patches. In addition, there appears to be high correlation between adjacent patches of high slip. Our results demonstrate that we can constrain complex non-planar fault geometry together with fault slip from GPS data using past seismicity as a priori

  3. Oil Secretory System in Vegetative Organs of Three Arnica Taxa: Essential Oil Synthesis, Distribution and Accumulation.

    PubMed

    Kromer, Krystyna; Kreitschitz, Agnieszka; Kleinteich, Thomas; Gorb, Stanislav N; Szumny, Antoni

    2016-05-01

    Arnica, a genus including the medicinal species A. montana, in its Arbo variety, and A. chamissonis, is among the plants richest in essential oils used as pharmaceutical materials. Despite its extensive use, the role of anatomy and histochemistry in the internal secretory system producing the essential oil is poorly understood. Anatomical sections allowed differentiation between two forms of secretory structures which differ according to their distribution in plants. The first axial type is connected to the vascular system of all vegetative organs and forms canals lined with epithelial cells. The second cortical type is represented by elongated intercellular spaces filled with oil formed only between the cortex cells of roots and rhizomes at maturity, with canals lacking an epithelial layer.Only in A. montana rhizomes do secretory structures form huge characteristic reservoirs. Computed tomography illustrates their spatial distribution and fusiform shape. The axial type of root secretory canals is formed at the interface between the endodermis and cortex parenchyma, while, in the stem, they are located in direct contact with veinal parenchyma. The peripheral phloem parenchyma cells are arranged in strands around sieve tube elements which possess a unique ability to accumulate large amounts of oil bodies. The cells of phloem parenchyma give rise to the aforementioned secretory structures while the lipid components (triacylglycerols) stored there support the biosynthesis of essential oils by later becoming a medium in which these oils are dissolved. The results indicate the integrity of axial secretory structures forming a continuous system in vegetative plant organs. PMID:26936790

  4. Oil Secretory System in Vegetative Organs of Three Arnica Taxa: Essential Oil Synthesis, Distribution and Accumulation.

    PubMed

    Kromer, Krystyna; Kreitschitz, Agnieszka; Kleinteich, Thomas; Gorb, Stanislav N; Szumny, Antoni

    2016-05-01

    Arnica, a genus including the medicinal species A. montana, in its Arbo variety, and A. chamissonis, is among the plants richest in essential oils used as pharmaceutical materials. Despite its extensive use, the role of anatomy and histochemistry in the internal secretory system producing the essential oil is poorly understood. Anatomical sections allowed differentiation between two forms of secretory structures which differ according to their distribution in plants. The first axial type is connected to the vascular system of all vegetative organs and forms canals lined with epithelial cells. The second cortical type is represented by elongated intercellular spaces filled with oil formed only between the cortex cells of roots and rhizomes at maturity, with canals lacking an epithelial layer.Only in A. montana rhizomes do secretory structures form huge characteristic reservoirs. Computed tomography illustrates their spatial distribution and fusiform shape. The axial type of root secretory canals is formed at the interface between the endodermis and cortex parenchyma, while, in the stem, they are located in direct contact with veinal parenchyma. The peripheral phloem parenchyma cells are arranged in strands around sieve tube elements which possess a unique ability to accumulate large amounts of oil bodies. The cells of phloem parenchyma give rise to the aforementioned secretory structures while the lipid components (triacylglycerols) stored there support the biosynthesis of essential oils by later becoming a medium in which these oils are dissolved. The results indicate the integrity of axial secretory structures forming a continuous system in vegetative plant organs.

  5. AP-1 and clathrin are essential for secretory granule biogenesis in Drosophila

    PubMed Central

    Burgess, Jason; Jauregui, Miluska; Tan, Julie; Rollins, Janet; Lallet, Sylvie; Leventis, Peter A.; Boulianne, Gabrielle L.; Chang, Henry C.; Le Borgne, Roland; Krämer, Helmut; Brill, Julie A.

    2011-01-01

     Regulated secretion of hormones, digestive enzymes, and other biologically active molecules requires the formation of secretory granules. Clathrin and the clathrin adaptor protein complex 1 (AP-1) are necessary for maturation of exocrine, endocrine, and neuroendocrine secretory granules. However, the initial steps of secretory granule biogenesis are only minimally understood. Powerful genetic approaches available in the fruit fly Drosophila melanogaster were used to investigate the molecular pathway for biogenesis of the mucin-containing “glue granules” that form within epithelial cells of the third-instar larval salivary gland. Clathrin and AP-1 colocalize at the trans-Golgi network (TGN) and clathrin recruitment requires AP-1. Furthermore, clathrin and AP-1 colocalize with secretory cargo at the TGN and on immature granules. Finally, loss of clathrin or AP-1 leads to a profound block in secretory granule formation. These findings establish a novel role for AP-1– and clathrin-dependent trafficking in the biogenesis of mucin-containing secretory granules. PMID:21490149

  6. HID-1 is required for homotypic fusion of immature secretory granules during maturation

    PubMed Central

    Du, Wen; Zhou, Maoge; Zhao, Wei; Cheng, Dongwan; Wang, Lifen; Lu, Jingze; Song, Eli; Feng, Wei; Xue, Yanhong; Xu, Pingyong; Xu, Tao

    2016-01-01

    Secretory granules, also known as dense core vesicles, are generated at the trans-Golgi network and undergo several maturation steps, including homotypic fusion of immature secretory granules (ISGs) and processing of prehormones to yield active peptides. The molecular mechanisms governing secretory granule maturation are largely unknown. Here, we investigate a highly conserved protein named HID-1 in a mouse model. A conditional knockout of HID-1 in pancreatic β cells leads to glucose intolerance and a remarkable increase in the serum proinsulin/insulin ratio caused by defective proinsulin processing. Large volume three-dimensional electron microscopy and immunofluorescence imaging reveal that ISGs are much more abundant in the absence of HID-1. We further demonstrate that HID-1 deficiency prevented secretory granule maturation by blocking homotypic fusion of immature secretory granules. Our data identify a novel player during the early maturation of immature secretory granules. DOI: http://dx.doi.org/10.7554/eLife.18134.001 PMID:27751232

  7. Excretory/secretory products from in vitro-cultured Echinococcus granulosus protoscoleces.

    PubMed

    Virginio, Veridiana G; Monteiro, Karina M; Drumond, Fernanda; de Carvalho, Marcos O; Vargas, Daiani M; Zaha, Arnaldo; Ferreira, Henrique B

    2012-05-01

    Cystic hydatid disease (CHD) is caused by infection with Echinococcus granulosus metacestodes and affects humans and livestock. Proteins secreted or excreted by protoscoleces, pre-adult worms found in the metacestode, are thought to play fundamental roles in the host-parasite relationship. In this work, we performed an LC-MS/MS proteomic analysis of the excretory-secretory products obtained from the first 48 h of an in vitro culture of the protoscoleces. We identified 32 proteins, including 18 that were never detected previously in metacestode proteomic studies. Among the novel identified excretory-secretory products are antigenic proteins, such as EG19 and P-29 and a calpain protease. We also identified other important protoscolex excretory-secretory products, such as thioredoxin peroxidase and 14-3-3 proteins, which are potentially involved in evasion mechanisms adopted by parasites to establish infection. Several intracellular proteins were found in the excretory-secretory products, revealing a set of identified proteins not previously thought to be exposed at the host-parasite interface. Additionally, immunological analyses established the antigenic profiles of the newly identified excretory-secretory products and revealed, for the first time, the in vitro secretion of the B antigen by protoscoleces. Considering that the excretory-secretory products obtained in vitro might reflect the products released and exposed to the host in vivo, our results provide valuable information on parasite survival strategies in adverse host environments and on the molecular mechanisms underpinning CHD immunopathology.

  8. Epithelial Cell Culture from Human Adenoids: A Functional Study Model for Ciliated and Secretory Cells

    PubMed Central

    González, Claudia; Espinosa, Marisol; Sánchez, María Trinidad; Droguett, Karla; Ríos, Mariana; Fonseca, Ximena; Villalón, Manuel

    2013-01-01

    Background. Mucociliary transport (MCT) is a defense mechanism of the airway. To study the underlying mechanisms of MCT, we have both developed an experimental model of cultures, from human adenoid tissue of ciliated and secretory cells, and characterized the response to local chemical signals that control ciliary activity and the secretion of respiratory mucins in vitro. Materials and Methods. In ciliated cell cultures, ciliary beat frequency (CBF) and intracellular Ca2+ levels were measured in response to ATP, UTP, and adenosine. In secretory cultures, mucin synthesis and secretion were identified by using immunodetection. Mucin content was taken from conditioned medium and analyzed in the presence or absence of UTP. Results. Enriched ciliated cell monolayers and secretory cells were obtained. Ciliated cells showed a basal CBF of 10.7 Hz that increased significantly after exposure to ATP, UTP, or adenosine. Mature secretory cells showed active secretion of granules containing different glycoproteins, including MUC5AC. Conclusion. Culture of ciliated and secretory cells grown from adenoid epithelium is a reproducible and feasible experimental model, in which it is possible to observe ciliary and secretory activities, with a potential use as a model to understand mucociliary transport control mechanisms. PMID:23484122

  9. The organization of the secretory machinery in chromaffin cells as a major factor in modeling exocytosis

    PubMed Central

    Villanueva, José; Torregrosa-Hetland, Cristina J.; Gil, Amparo; González-Vélez, Virginia; Segura, Javier; Viniegra, Salvador; Gutiérrez, Luis M.

    2010-01-01

    The organization of cytoplasm in excitable cells was a largely ignored factor when mathematical models were developed to understand intracellular calcium and secretory behavior. Here we employed a combination of fluorescent evanescent and transmitted light microscopy to explore the F-actin cytoskeletal organization in the vicinity of secretory sites in cultured bovine chromaffin cells. This technique and confocal fluorescent microscopy show chromaffin granules associated with the borders of cortical cytoskeletal cages forming an intricate tridimensional network. Furthermore, the overexpression of SNAP-25 in these cells also reveals the association of secretory machinery clusters with the borders of these cytoskeletal cages. The importance of these F-actin cage borders is stressed when granules appear to interact and remain associated during exocytosis visualized in acridin orange loaded vesicles. These results will prompt us to propose a model of cytoskeletal cages, where the secretory machinery is associated with its borders. Both the calcium level and the secretory response are enhanced in this geometrical arrangement when compared with a random distribution of the secretory machinery that is not restricted to the borders of the cage. PMID:20885775

  10. Regulation of secretory granule size by the precise generation and fusion of unit granules

    PubMed Central

    Hammel, Ilan; Lagunoff, David; Galli, Stephen J

    2010-01-01

    Abstract Morphometric evidence derived from studies of mast cells, pancreatic acinar cells and other cell types supports a model in which the post-Golgi processes that generate mature secretory granules can be resolved into three steps: (1) fusion of small, Golgi-derived progranules to produce immature secretory granules which have a highly constrained volume; (2) transformation of such immature granules into mature secretory granules, a process often associated with a reduction in the maturing granule’s volume, as well as changes in the appearance of its content and (3) fusion of secretory granules of the smallest size, termed ‘unit granules’, forming granules whose volumes are multiples of the unit granule’s volume. Mutations which perturb this process can cause significant pathology. For example, Chediak–Higashi syndrome / lysosomal trafficking regulator (CHS)/(Lyst) mutations result in giant secretory granules in a number of cell types in human beings with the Chediak–Higashi syndrome and in ‘beige’ (Lystbg/Lystbg) mice. Analysis of the secretory granules of mast cells and pancreatic acinar cells in Lyst-deficient beige mice suggests that beige mouse secretory granules retain the ability to fuse randomly with other secretory granules no matter what the size of the fusion partners. By contrast, in normal mice, the pattern of granule–granule fusion occurs exclusively by the addition of unit granules, either to each other or to larger granules. The normal pattern of fusion is termed unit addition and the fusion evident in cells with CHS/Lyst mutations is called random addition. The proposed model of secretory granule formation has several implications. For example, in neurosecretory cells, the secretion of small amounts of cargo in granules constrained to a very narrow size increases the precision of the information conveyed by secretion. By contrast, in pancreatic acinar cells and mast cells, large granules composed of multiple unit granules

  11. Short-term cholinergic desensitization of rat pancreatic secretory response

    SciTech Connect

    Asselin, J.; Larose, L.; Morisset, J.

    1987-03-01

    Dispersed pancreatic acini were first exposed to carbamylcholine (10/sup -7/-10/sup -4/ M) for 60 min, washed, and reexposed to this same agonist (10/sup -8/-10/sup -3/ M) for 15 min. During this second incubation, the functional secretory capacity of these acini was evaluated by measuring amylase release. Acini preexposed to concentrations of carbamylcholine of 10/sup -6/ M or greater showed shifts to the right in the subsequent carbamylcholine dose-response curves of amylase release. A 3-h recovery period (without carbamylcholine) did not restore the altered carbamylcholine dose-response curve. Ca/sup 2 +/ concentrations of 10/sup -7/ M or 2.5 x 10/sup -3/ M instead of 0.5 x 10/sup -3/ M during the 60-min preincubation did not affect the desensitization process. With use of N-(/sup 3/H)methylscopolamine to evaluate muscarinic receptors, the only changes observed after desensitization were a significant decrease in the high-affinity and an equivalent increase in that of the low-affinity receptors. After cholinergic exposure amylase release stimulated by caerulein was only slightly modified, whereas amylase release in response to a phorbol ester 12-O-tetradecanoylphorbol-13-acetate and to the ionophore A23187 was not altered. These data indicate that short-term desensitization with a cholinergic agent is relatively specific to muscarinic agonists, causes changes in the muscarinic receptor high-and low-affinity concentration but does not alter intracellular steps after calcium mobilization or protein kinase C activation known to be involved in the secretion process.

  12. Myosin Vc Is Specialized for Transport on a Secretory Superhighway.

    PubMed

    Sladewski, Thomas E; Krementsova, Elena B; Trybus, Kathleen M

    2016-08-22

    A hallmark of the well-studied vertebrate class Va myosin is its ability to take multiple steps on actin as a single molecule without dissociating, a feature called "processivity." Therefore, it was surprising when kinetic and single-molecule assays showed that human myosin Vc (MyoVc) was not processive on single-actin filaments [1-3]. We explored the possibility that MyoVc is processive only under conditions that resemble its biological context. Recently, it was shown that zymogen vesicles are transported on actin "superhighways" composed of parallel actin cables nucleated by formins from the plasma membrane [4]. Loss of these cables compromises orderly apical targeting of vesicles. MyoVc has been implicated in transporting secretory vesicles to the apical membrane [5]. We hypothesized that actin cables regulate the processive properties of MyoVc. We show that MyoVc is unique in taking variable size steps, which are frequently in the backward direction. Results obtained with chimeric constructs implicate the lever arm/rod of MyoVc as being responsible for these properties. Actin bundles allow single MyoVc motors to move processively. Remarkably, even teams of MyoVc motors require actin bundles to move continuously at physiological ionic strength. The irregular stepping pattern of MyoVc, which may result from flexibility in the lever arm/rod of MyoVc, appears to be a unique structural adaptation that allows the actin track to spatially restrict the activity of MyoVc to specialized actin cables in order to co-ordinate and target the final stages of vesicle secretion. PMID:27498562

  13. Myosin Vc Is Specialized for Transport on a Secretory Superhighway.

    PubMed

    Sladewski, Thomas E; Krementsova, Elena B; Trybus, Kathleen M

    2016-08-22

    A hallmark of the well-studied vertebrate class Va myosin is its ability to take multiple steps on actin as a single molecule without dissociating, a feature called "processivity." Therefore, it was surprising when kinetic and single-molecule assays showed that human myosin Vc (MyoVc) was not processive on single-actin filaments [1-3]. We explored the possibility that MyoVc is processive only under conditions that resemble its biological context. Recently, it was shown that zymogen vesicles are transported on actin "superhighways" composed of parallel actin cables nucleated by formins from the plasma membrane [4]. Loss of these cables compromises orderly apical targeting of vesicles. MyoVc has been implicated in transporting secretory vesicles to the apical membrane [5]. We hypothesized that actin cables regulate the processive properties of MyoVc. We show that MyoVc is unique in taking variable size steps, which are frequently in the backward direction. Results obtained with chimeric constructs implicate the lever arm/rod of MyoVc as being responsible for these properties. Actin bundles allow single MyoVc motors to move processively. Remarkably, even teams of MyoVc motors require actin bundles to move continuously at physiological ionic strength. The irregular stepping pattern of MyoVc, which may result from flexibility in the lever arm/rod of MyoVc, appears to be a unique structural adaptation that allows the actin track to spatially restrict the activity of MyoVc to specialized actin cables in order to co-ordinate and target the final stages of vesicle secretion.

  14. Postnatal development of bile secretory physiology in the dog

    SciTech Connect

    Tavoloni, N.; Jones, M.J.; Berk, P.D.

    1985-04-01

    To determine whether bile formation in the dog is an immature process at birth, several determinants of bile secretion were studied in anesthetized, bile duct-cannulated puppies of 0-42 days of age and adult dogs. Basal canalicular bile flow rate, estimated by /sup 14/C-erythritol biliary clearance, averaged 0.182 microliter/min/g liver in 0-3 day-old puppies and increased to 0.324 and 0.461 microliter/min/g in puppies 7-21 and 28-42 days of age, respectively. Calculated ductular bile water reabsorption (/sup 14/C-erythritol biliary clearance-bile flow) was virtually absent in 0-3 day-old puppies, and averaged 0.017 and 0.092 microliter/min/g in puppies of 7-21 and 28-42 days of age, respectively. In adult dogs, ductular bile water reabsorption was 0.132 microliter/min/g. These functional deficiencies of the newborn dog were associated with an increased biliary permeability to /sup 3/H-inulin which could not be accounted for solely by an increased solute diffusion due to the lower rate of canalicular bile flow. Administration of taurocholate up to 2000 nmol/min/kg produced in all animals a similar increase in canalicular bile flow and bile acid excretion, and was not associated with changes in ductular bile water reabsorption rate. These findings are interpreted to indicate that, in the dog, bile secretory function is immature at birth and develops during postnatal life.

  15. Secretory pathway Ca2+/Mn2+-ATPase isoform 2 and lactation: specific localization of plasmalemmal and secretory pathway Ca2+ pump isoforms in the mammary gland

    SciTech Connect

    Faddy, Helen M.; Smart, Chanel E.; Xu, Ren; Lee, Genee Y.; Kenny, Paraic A.; Feng, Mingye; Rao, Rajini; Brown, Melissa A.; Bissell, Mina J.; Roberts-Thomson, Sarah J.; Monteith, Gregory R.

    2008-04-09

    The supply of calcium to the developing neonate via milk is an important physiological process. Until recently the mechanism for the enrichment of milk with calcium was thought to be almost entirely mediated via the secretory pathway. However, recent studies suggest that a specific isoform of the plasma membrane calcium ATPase, PMCA2, is the primary mechanism for calcium transport into milk, highlighting a major role for apical calcium transport. We compared the expression of the recently identified secretory calcium ATPase, SPCA2, and SPCA1, in the mouse mammary gland during different stages of development. SPCA2 levels increased over 35 fold during lactation, while SPCA1 increased only a modest two fold. The potential importance of SPCA2 in lactation was also highlighted by its localization to luminal secretory cells of the mammary gland during lactation, while SPCA1 was expressed throughout the cells of the mammary gland. We also observed major differences in the localization of PMCA2 and PMCA1 during lactation. Using the SCp2 mouse mammary epithelial cell 3D culture model, differences in the sub-cellular distribution of PMCA2 and PMCA1 were clear. These studies highlight the likely specific roles of PMCA2 and SPCA2 in lactation, and link the recently characterized SPCA2 calcium pump to the supply of calcium into milk and the regulation of Golgi resident enzymes important in lactation. They also indicate that calcium transport into milk is a complex interplay between apical and secretory pathways.

  16. Fast simulation methods for non-planar phase and multilayer defects in DUV and EUV photomasks for lithography

    NASA Astrophysics Data System (ADS)

    Lam, Michael Christopher

    This dissertation develops rapid modeling methodologies for the printability and inspectability of various types of defects on photomasks in DUV and EUV lithography. Several fast and approximate methods for defect simulation are introduced and validated by comparing their results with Finite Difference Time Domain (FDTD) calculations of scattering from the same geometry. The common strategy is to decompose the electromagnetic (EM) scattering into individual signal contributions by analyzing rigorous simulations, and then to develop efficient alternative models for each contribution. Two methods are introduced to calculate the observed scattering from DUV phase defects. First, the through focus behavior of an isolated defect can be used to extract two defect parameters, size and phase, which fully characterize the defect by means of an EM equivalent thin mask model. Post and void defects can also be differentiated based on the side of defocus that their peak signal occurs. Second, a defect projector methodology is introduced that allows results for an isolated defect and a defect-free pattern to be combined to predict their interaction for any defect location. The defect projector is four orders of magnitude faster than 3D FDTD simulation, and can correctly predict the defect induced dimension change to within 30% for worst case. The main emphasis of this dissertation is on scattering from non-planar multilayer structures to understand the printability of buried defects inside of EUV mask blanks. A new method based on ray tracing is developed by exploiting the small non-specular forward angular scattering of individual bilayers, which is 10X smaller than the back scatter, and its approximation as zero allows a new and tractable mathematical factoring. The method is tested for various deposition strategies, defect sizes, defect shapes, as well as various illumination angles of incidence and polarization. Smoothing of the defect shape during deposition is confirmed to

  17. Multiphoton fluorescence lifetime imaging shows spatial segregation of secondary metabolites in Eucalyptus secretory cavities.

    PubMed

    Heskes, A M; Lincoln, C N; Goodger, J Q D; Woodrow, I E; Smith, T A

    2012-07-01

    Multiphoton fluorescence lifetime imaging provides an excellent tool for imaging deep within plant tissues while providing a means to distinguish between fluorophores with high spatial and temporal resolution. Ideal candidates for the application of multiphoton fluorescence lifetime imaging to plants are the embedded secretory cavities found in numerous species because they house complex mixtures of secondary metabolites within extracellular lumina. Previous investigations of this type of structure have been restricted by the use of sectioned material resulting in the loss of lumen contents and often disorganization of the delicate secretory cells; thus it is not known if there is spatial segregation of secondary metabolites within these structures. In this paper, we apply multiphoton fluorescence lifetime imaging to investigate the spatial arrangement of metabolites within intact secretory cavities isolated from Eucalyptus polybractea R.T. Baker leaves. The secretory cavities of this species are abundant (up to 10 000 per leaf), large (up to 6 nL) and importantly house volatile essential oil rich in the monoterpene 1,8-cineole, together with an immiscible, non-volatile component comprised largely of autofluorescent oleuropeic acid glucose esters. We have been able to optically section into the lumina of secretory cavities to a depth of ∼80 μm, revealing a unique spatial organization of cavity metabolites whereby the non-volatile component forms a layer between the secretory cells lining the lumen and the essential oil. This finding could be indicative of a functional role of the non-volatile component in providing a protective region of low diffusivity between the secretory cells and potentially autotoxic essential oil.

  18. Estradiol increases cAMP in the oviductal secretory cells through a nongenomic mechanism.

    PubMed

    Oróstica, María L; Lopez, John; Rojas, Israel; Rocco, Jocelyn; Díaz, Patricia; Reuquén, Patricia; Cardenas, Hugo; Parada-Bustamante, Alexis; Orihuela, Pedro A

    2014-09-01

    In the rat oviduct, estradiol (E2) accelerates egg transport by a nongenomic action that requires previous conversion of E2 to methoxyestrogens via catechol-O-methyltranferase (COMT) and activation of estrogen receptor (ER) with subsequent production of cAMP and inositol triphosphate (IP3). However, the role of the different oviductal cellular phenotypes on this E2 nongenomic pathway remains undetermined. The aim of this study was to investigate the effect of E2 on the levels of cAMP and IP3 in primary cultures of secretory and smooth muscle cells from rat oviducts and determine the mechanism by which E2 increases cAMP in the secretory cells. In the secretory cells, E2 increased cAMP but not IP3, while in the smooth muscle cells E2 decreased cAMP and increased IP3. Suppression of protein synthesis by actinomycin D did not prevent the E2-induced cAMP increase, but this was blocked by the ER antagonist ICI 182 780 and the inhibitors of COMT OR 486, G protein-α inhibitory (Gαi) protein pertussis toxin and adenylyl cyclase (AC) SQ 22536. Expression of the mRNA for the enzymes that metabolizes estrogens, Comt, Cyp1a1, and Cyp1b1 was found in the secretory cells, but this was not affected by E2. Finally, confocal immunofluorescence analysis showed that E2 induced colocalization between ESR1 (ERα) and Gαi in extranuclear regions of the secretory cells. We conclude that E2 differentially regulates cAMP and IP3 in the secretory and smooth muscle cells of the rat oviduct. In the secretory cells, E2 increases cAMP via a nongenomic action that requires activation of COMT and ER, coupling between ESR1 and Gαi, and stimulation of AC.

  19. Nonplanar Monocyanines: Meso-Substituted Thiazole Orange with High Photostability and Their Synthetic Strategy as well as a Cell Association Study.

    PubMed

    Guan, Li; Li, Anyang; Song, Yinyin; Yan, Mengqi; Gao, Dengfeng; Zhang, Xianghan; Li, Bin; Wang, Lanying

    2016-08-01

    A convenient approach for the direct synthesis of meso-substituted thiazole orange (meso-TO) analogues has been unprecedentedly developed through the AlCl3-catalyzed reaction of parent TO with benzyl alcohol derivatives. Single-crystal X-ray structures show that the prepared new meso-TO analogues are nonplanar, forming a sharp contrast to planar TO. The spectral properties show that nonplanar meso-TO analogues do not aggregate, existing in monomer form (M) in PBS buffer, and have little effect of solvatochromism in different solvents. In comparison with the parents, meso-TO analogues exhibit a large Stokes shift, excellent light fastness, and inertness to singlet oxygen. A cellular association study demonstrates that incorporation of a benzyl group at the meso position methine of parent TO can decrease the cytotoxicity, change staining area in cells, and emit long-wavelength fluorescence for an extended time, which are useful for the development of smarter TOs for imaging in biological science. PMID:27379526

  20. Nonplanar Monocyanines: Meso-Substituted Thiazole Orange with High Photostability and Their Synthetic Strategy as well as a Cell Association Study.

    PubMed

    Guan, Li; Li, Anyang; Song, Yinyin; Yan, Mengqi; Gao, Dengfeng; Zhang, Xianghan; Li, Bin; Wang, Lanying

    2016-08-01

    A convenient approach for the direct synthesis of meso-substituted thiazole orange (meso-TO) analogues has been unprecedentedly developed through the AlCl3-catalyzed reaction of parent TO with benzyl alcohol derivatives. Single-crystal X-ray structures show that the prepared new meso-TO analogues are nonplanar, forming a sharp contrast to planar TO. The spectral properties show that nonplanar meso-TO analogues do not aggregate, existing in monomer form (M) in PBS buffer, and have little effect of solvatochromism in different solvents. In comparison with the parents, meso-TO analogues exhibit a large Stokes shift, excellent light fastness, and inertness to singlet oxygen. A cellular association study demonstrates that incorporation of a benzyl group at the meso position methine of parent TO can decrease the cytotoxicity, change staining area in cells, and emit long-wavelength fluorescence for an extended time, which are useful for the development of smarter TOs for imaging in biological science.

  1. Characteristics and Modeling of a Nonplanar Nonrectangular Metal Oxide Semiconductor Field Effect Transistor for Charge Sensing in the Si Micro-Fluidic Channel

    NASA Astrophysics Data System (ADS)

    Lim, Geunbae; Kim, Dong-Sun; Lyu, Hong-Kun; Park, Hey-Jung; Shin, Jang-Kyoo; Choi, Pyung; Lee, Jong-Hyun; Lee, Minho

    2004-06-01

    In this work, a nonplanar, nonrectangular metal-oxide-semiconductor field effect transistor (MOSFET) with an asymmetrical channel structure for sensing charge in the Si micro-fluidic channel was fabricated, and the electrical characteristics of the fabricated three-dimensional (3-D) MOSFET were measured. The device was formed in the convex corner of a Si micro-fluidic channel using tetramethyl ammonium hydroxide (TMAH) anistropic etching solution, so that it would be suitable for combination with a micro-fluidic system. We approximated the nonplanar, nonrectangular 3-D MOSFET to a two-dimensional rectangular structure using the Schwartz-Christoffel transformation. The LEVEL1 device parameters of the 3-D MOSFET were extracted from the measured electrical device characteristics and were used in a simulation program with integrated circuit emphasis (SPICE) simulation. The measured and simulated results for the 3-D MOSFET were compared and found to show good agreement. We also investigated the feasibility of the proposed 3-D MOSFET as a charge sensor for detecting charged biomolecules.

  2. Modulation of dendritic cell function by Trichomonas vaginalis-derived secretory products.

    PubMed

    Song, Min-Ji; Lee, Jong-Joo; Nam, Young Hee; Kim, Tae-Gyun; Chung, Youn Wook; Kim, Mikyoung; Choi, Ye-Eun; Shin, Myeong Heon; Kim, Hyoung-Pyo

    2015-02-01

    Trichomoniasis caused by the parasitic protozoan Trichomonas vaginalis is the most common sexually transmitted disease in the world. Dendritic cells are antigen presenting cells that initiate immune responses by directing the activation and differentiation of naïve T cells. In this study, we analyzed the effect of Trichomonas vaginalis-derived Secretory Products on the differentiation and function of dendritic cells. Differentiation of bone marrow-derived dendritic cells in the presence of T. vaginalis-derived Secretory Products resulted in inhibition of lipopolysaccharide-induced maturation of dendritic cells, down-regulation of IL-12, and up-regulation of IL-10. The protein components of T. vaginalis-derived Secretory Products were shown to be responsible for altered function of bone marrow- derived dendritic cells. Chromatin immunoprecipitation assay demonstrated that IL-12 expression was regulated at the chromatin level in T. vaginalis-derived Secretory Productstreated dendritic cells. Our results demonstrated that T. vaginalis- derived Secretory Products modulate the maturation and cytokine production of dendritic cells leading to immune tolerance.

  3. The Ypt1 GTPase is essential for the first two steps of the yeast secretory pathway.

    PubMed

    Jedd, G; Richardson, C; Litt, R; Segev, N

    1995-11-01

    Small GTPases of the rab family are involved in the regulation of vesicular transport. The restricted distribution of each of these proteins in mammalian cells has led to the suggestion that different rab proteins act at different steps of transport (Pryer, N. K., L. J. Wuestehube, and R. Sheckman. 1992. Annu Rev. Biochem. 61:471-516; Zerial, M., and H. Stenmark. 1993. Curr. Opin. Cell Biol. 5:613-620). However, in this report we show that the Ypt1-GTPase, a member of the rab family, is essential for more than one step of the yeast secretory pathway. We determined the secretory defect conferred by a novel ypt1 mutation by comparing the processing of several transported glycoproteins in wild-type and mutant cells. The ypt1-A136D mutant has a change in an amino acid that is conserved among rab GTPases. This mutation leads to a rapid and tight secretory block upon a shift to the restrictive temperature, and allows for the identification of the specific steps in the secretory pathway that directly require Ypt1 protein (Ypt1p). The ypt1-A136D mutant exhibits tight blocks in two secretory steps, ER to cis-Golgi and cis- to medial-Golgi, but later steps are unaffected. Thus, it is unlikely that Ypt1p functions as the sole determinant of fusion specificity. Our results are more consistent with a role for Ypt1/rab proteins in determining the directionality or fidelity of protein sorting.

  4. Coordinated activation of the secretory pathway during notochord formation in the Xenopus embryo

    PubMed Central

    Tanegashima, Kosuke; Zhao, Hui; Rebbert, Martha L.; Dawid, Igor B.

    2009-01-01

    Summary We compared the transcriptome in the developing notochord of Xenopus laevis embryos with that of other embryonic regions. A coordinated and intense activation of a large set of secretory pathway genes was observed in the notochord, but not in notochord precursors in the axial mesoderm at early gastrula stage. The genes encoding Xbp1 and Creb3l2 were also activated in the notochord. These two transcription factors are implicated in the activation of secretory pathway genes during the unfolded protein response, where cells react to the stress of a build-up of unfolded proteins in their endoplasmic reticulum. Xbp1 and Creb3l2 are differentially expressed but not differentially activated in the notochord. Reduction of expression of Xbp1 or Creb3l2 by injection of antisense morpholinos led to strong deficits in notochord but not somitic muscle development. In addition, the expression of some, but not all, genes encoding secretory proteins was inhibited by injection of xbp1 morpholinos. Furthermore, expression of activated forms of Xbp1 or Creb3l2 in animal explants could activate a similar subset of secretory pathway genes. We conclude that coordinated activation of a battery of secretory pathway genes mediated by Xbp1 and Creb/ATF factors is a characteristic and necessary feature of notochord formation. PMID:19793890

  5. Effects of 5-fluorouracil on the secretory process of the rat parotid gland

    SciTech Connect

    Sandborg, R.R.

    1986-01-01

    Experimental animals were injected intraperitoneally with 100 mg/kg 5-fluorouracil for three days. The total volume, amylase and protein content of cannulated parotid saliva were determined following stimulation with either 5 mg/kg pilocarpine or 5 mg/kg isoproterenol in experimental, pair-fed , and control animals. Saliva from experimental animals was significantly lower in volume, amylase and protein content than both control groups. 5-fluorouracil treatment reduced the total glandular amylase per unit DNA in both unstimulated and isoproterenol-stimulated parotid glands. Decreased protein synthesis may be the mechanism underlying depleted secretory protein stores since the contents of isolated secretory granules from experimental parotid glands contained less radiolabelled protein than either control group and whole gland homogenates showed marked reductions in the activities of three lysosomal enzymes and total RNA content. Experimental animals contained less labelled protein in their secretory granules than controls, but secreted a greater proportion of their total glandular radiolabelled secretory protein into saliva relative to amylase suggesting that newly synthesized secretory proteins are preferentially secreted.

  6. Preservation of Facial Nerve With Adjuvant Radiotherapy for Recurrent Mammary Analogue Secretory Carcinoma of Parotid Gland.

    PubMed

    Jin, Shufang; Ma, Hailong; He, Yue

    2016-06-01

    Mammary analogue secretory carcinoma of salivary glands harbors the recurrent ETV6-NTRK3 gene fusion because of the translocation t (12; 15) (p13; q25) and resembles breast secretory carcinoma. This tumor composed of papillary, cystic, solid, and cribriform patterns. Immunohistochemically, the tumors are positive for mammaglobin, CK7, CK8, STAT5a, vimentin, and S100. In this report, the authors presented a patient of recurrent parotid gland mammary analogue secretory carcinoma in a 22-year-old woman. The patient received extended parotidectomy with partial adhesive masseter surgery. The facial nerve was preserved during the surgery and adjuvant radiotherapy was performed postoperation. The patient did not suffer local recurrence and facial paralysis in the 18 months follow-up period. PMID:27192652

  7. Insulin granules. Insulin secretory granules control autophagy in pancreatic β cells.

    PubMed

    Goginashvili, Alexander; Zhang, Zhirong; Erbs, Eric; Spiegelhalter, Coralie; Kessler, Pascal; Mihlan, Michael; Pasquier, Adrien; Krupina, Ksenia; Schieber, Nicole; Cinque, Laura; Morvan, Joëlle; Sumara, Izabela; Schwab, Yannick; Settembre, Carmine; Ricci, Romeo

    2015-02-20

    Pancreatic β cells lower insulin release in response to nutrient depletion. The question of whether starved β cells induce macroautophagy, a predominant mechanism maintaining energy homeostasis, remains poorly explored. We found that, in contrast to many mammalian cells, macroautophagy in pancreatic β cells was suppressed upon starvation. Instead, starved β cells induced lysosomal degradation of nascent secretory insulin granules, which was controlled by protein kinase D (PKD), a key player in secretory granule biogenesis. Starvation-induced nascent granule degradation triggered lysosomal recruitment and activation of mechanistic target of rapamycin that suppressed macroautophagy. Switching from macroautophagy to insulin granule degradation was important to keep insulin secretion low upon fasting. Thus, β cells use a PKD-dependent mechanism to adapt to nutrient availability and couple autophagy flux to secretory function.

  8. A Highly Sensitive Assay for Monitoring the Secretory Pathway and ER Stress

    PubMed Central

    Breakefield, Xandra O.; Tannous, Bakhos A.

    2007-01-01

    Background The secretory pathway is a critical index of the capacity of cells to incorporate proteins into cellular membranes and secrete proteins into the extracellular space. Importantly it is disrupted in response to stress to the endoplasmic reticulum that can be induced by a variety of factors, including expression of mutant proteins and physiologic stress. Activation of the ER stress response is critical in the etiology of a number of diseases, such as diabetes and neurodegeneration, as well as cancer. We have developed a highly sensitive assay to monitor processing of proteins through the secretory pathway and endoplasmic reticulum (ER) stress in real-time based on the naturally secreted Gaussia luciferase (Gluc). Methodology/Principle Findings An expression cassette for Gluc was delivered to cells, and its secretion was monitored by measuring luciferase activity in the conditioned medium. Gluc secretion was decreased down to 90% when these cells were treated with drugs that interfere with the secretory pathway at different steps. Fusing Gluc to a fluorescent protein allowed quantitation and visualization of the secretory pathway in real-time. Expression of this reporter protein did not itself elicit an ER stress response in cells; however, Gluc proved very sensitive at sensing this type of stress, which is associated with a temporary decrease in processing of proteins through the secretory pathway. The Gluc secretion assay was over 20,000-fold more sensitive as compared to the secreted alkaline phosphatase (SEAP), a well established assay for monitoring of protein processing and ER stress in mammalian cells. Conclusions/Significance The Gluc assay provides a fast, quantitative and sensitive technique to monitor the secretory pathway and ER stress and its compatibility with high throughput screening will allow discovery of drugs for treatment of conditions in which the ER stress is generally induced. PMID:17593970

  9. Secretory end-feet, extracerebral cells, and cerebral sense organs in certain limicole oligochaete annelids.

    PubMed

    Golding, D W; Whittle, A C

    1975-01-01

    Secretory end-feet (or SEF) systems are present in Limnodrilus and Stylodrilus but are less highly organized than those of polychaetes. SEF contain secretory vesicles and abundant mitochondria. Typical neurosecretory terminals are not found within the brain although "neurosecretory" perikarya are present in all four species studied. In Limnodrilus, Stylodrilus and Enchytraeus extracerebral cells, of probable neurosecretory function, are invested by the pericapsular epithelium. Characteristically such cells bear several cilia. In these species and in Stylaria a pair of sensory cell groups is located anteriorly within the brain. These cells are ciliated but lack associated supporting cells. PMID:170709

  10. The secretory membrane system studied in real-time. Robert Feulgen Prize Lecture, 2001.

    PubMed

    Lippincott-Schwartz, J

    2001-08-01

    The discovery and development of green fluorescent protein (GFP) from the jellyfish, Aequorea victoria, has revolutionized studies on protein localization and dynamics by allowing direct observation of a protein's life history and pathway in living cells, previously only deduced from genetic, biochemical, or immunolabeling studies. Applied to the secretory membrane system, which regulates delivery of newly synthesized proteins and lipids to the cell surface, GFP-based studies are providing important new insights into the maintenance and biogenesis of organelles, as well as the origin, pathway, and fate of secretory transport intermediates.

  11. Secretory organelles in ECL cells of the rat stomach: an immunohistochemical and electron-microscopic study.

    PubMed

    Zhao, C M; Chen, D; Lintunen, M; Panula, P; Håkanson, R

    1999-12-01

    ECL cells are numerous in the rat stomach. They produce and store histamine and chromogranin-A (CGA)-derived peptides such as pancreastatin and respond to gastrin with secretion of these products. Numerous electron-lucent vesicles of varying size and a few small, dense-cored granules are found in the cytoplasm. Using confocal and electron microscopy, we examined these organelles and their metamorphosis as they underwent intracellular transport from the Golgi area to the cell periphery. ECL-cell histamine was found to occur in both cytosol and secretory vesicles. Histidine decarboxylase, the histamine-forming enzyme, was in the cytosol, while pancreastatin (and possibly other peptide products) was confined to the dense cores of granules and secretory vesicles. Dense-cored granules and small, clear microvesicles were more numerous in the Golgi area than in the docking zone, i.e. close to the plasma membrane. Secretory vesicles were numerous in both Golgi area and docking zone, where they were sometimes seen to be attached to the plasma membrane. Upon acute gastrin stimulation, histamine was mobilized and the compartment size (volume density) of secretory vesicles in the docking zone was decreased, while the compartment size of microvesicles was increased. Based on these findings, we propose the following life cycle of secretory organelles in ECL cells: small, electron-lucent microvesicles (pro-granules) bud off the trans Golgi network, carrying proteins and secretory peptide precursors (such as CGA and an anticipated prohormone). They are transformed into dense-cored granules (approximate profile diameter 100 nm) while still in the trans Golgi area. Pro-granules and granules accumulate histamine, which leads to their metamorphosis into dense-cored secretory vesicles. In the Golgi area the secretory vesicles have an approximate profile diameter of 150 nm. By the time they reach their destination in the docking zone, their profile diameter is between 200 and 500 nm

  12. The secretory membrane system studied in real-time. Robert Feulgen Prize Lecture, 2001.

    PubMed

    Lippincott-Schwartz, J

    2001-08-01

    The discovery and development of green fluorescent protein (GFP) from the jellyfish, Aequorea victoria, has revolutionized studies on protein localization and dynamics by allowing direct observation of a protein's life history and pathway in living cells, previously only deduced from genetic, biochemical, or immunolabeling studies. Applied to the secretory membrane system, which regulates delivery of newly synthesized proteins and lipids to the cell surface, GFP-based studies are providing important new insights into the maintenance and biogenesis of organelles, as well as the origin, pathway, and fate of secretory transport intermediates. PMID:11685538

  13. A rare case of secretory breast carcinoma in a male adult with axillary lymph node metastasis.

    PubMed

    Ding, Jinhua; Jiang, Li; Gan, Yongli; Wu, Weizhu

    2015-01-01

    Secretory breast carcinoma is a rare tumor originally described in children but occurring equally in adult population, especially in women. This unusual subtype has a generally favorable prognosis, although several cases have been described in adults with increased aggressiveness and a risk of metastases even death. So far, merely ten cases of secretory breast carcinoma with metastatic axillary lymph node in male were reported. Here, we describe the eleventh case, a 24-years-old male who presented with a painless mass in the right breast was diagnosed to be "secretary breast carcinoma", and subsequently underwent modified radical mastectomy and adjuvant chemotherapy.

  14. Resonantly pumped monolithic nonplanar Ho:YAG ring laser with high-power single-frequency laser output at 2122 nm.

    PubMed

    Wang, Lei; Gao, Chunqing; Gao, Mingwei; Li, Yan

    2013-04-22

    We demonstrated a stable single-frequency laser operating at 2122 nm from a monolithic nonplanar Ho:YAG ring oscillator (NPRO). The Ho:YAG NPRO was resonantly pumped by a 1907 nm Tm:YLF laser built up by ourselves. The maximum multimode output power from the Ho:YAG NPRO was 9.66 W and the slope efficiency was 71.7%. With accurate adjustment of the pump position to make the laser oscillate in single frequency condition, an output power of 8.0 W was obtained with a slope efficiency of 61.4% and an optical-optical efficiency of 50.0%. The power stability of the Ho:YAG NPRO laser was 0.29% at maximum single frequency output power. The beam quality M(2) factors were measured to be less than 1.1 in x- and y- directions.

  15. White emission from non-planar InGaN/GaN MQW LEDs grown on GaN template with truncated hexagonal pyramids.

    PubMed

    Lee, Ming-Lun; Yeh, Yu-Hsiang; Tu, Shang-Ju; Chen, P C; Lai, Wei-Chih; Sheu, Jinn-Kong

    2015-04-01

    Non-planar InGaN/GaN multiple quantum well (MQW) structures are grown on a GaN template with truncated hexagonal pyramids (THPs) featuring c-plane and r-plane surfaces. The THP array is formed by the regrowth of the GaN layer on a selective-area Si-implanted GaN template. Transmission electron microscopy shows that the InGaN/GaN epitaxial layers regrown on the THPs exhibit different growth rates and indium compositions of the InGaN layer between the c-plane and r-plane surfaces. Consequently, InGaN/GaN MQW light-emitting diodes grown on the GaN THP array emit multiple wavelengths approaching near white light.

  16. Nonplanar structure of C6H5SCF3 facilitates πσ∗-mediated photodissociation reaction on the S1 state

    NASA Astrophysics Data System (ADS)

    Kim, So-Yeon; Lee, Jeongmook; Kim, Sang Kyu; Choi, Young S.

    2016-08-01

    Vibrational structure of trifluoromethylthiobenzene (C6H5SCF3) on the S1 state has been investigated by resonance-enhanced two-photon ionization spectroscopy and nature of predissociation dynamics is inferred from homogeneously broadened spectral features. As C6H5SCF3 adopts a nonplanar structure in both the S0 and S1 states, the effective adiabatic barrier generated by avoided crossing of optically-bright bound S1 (ππ∗) and dark-repulsive S2 (πσ∗) surfaces along the reaction coordinate is significantly lowered, giving the S1 lifetime of ∼300 fs. This experiment demonstrates that the molecular structure spanned by the reactive flux near the curve-crossing region dictates reaction rate as well as nonadiabatic transition probability.

  17. Comment on ``The effects of Bohm potential on ion-acoustic solitary waves interaction in a nonplanar quantum plasma'' [Phys. Plasmas 17, 082307 (2010)

    NASA Astrophysics Data System (ADS)

    Akbari-Moghanjoughi, M.

    2010-11-01

    Recently, Li [Phys. Plasmas 17, 082307 (2010)] has studied the effects of Bohm potential on interaction of nonplanar ion-acoustic solitary waves in an unmagnetized electron-positron-ion quantum plasma. In his work the extended reductive perturbation technique has been employed to reduce the basic quantum hydrodynamics plasma equations to Korteweg-de Vries evolution equations (one for each wave) as well as other coupled differential equations describing the phase variation of the resulting solitary waves. The calculated collisional phase-shifts are then numerically evaluated in terms of plasma parameters such as the fractional positron to ion number-density p, relative electron to positron Fermi-temperature σ and the quantum diffraction parameter H. We show that in the chosen plasma model, the parameters p and σ are not independent quantum plasma parameters which has important consequences on the graphical interpretations presented in the mentioned article.

  18. Comment on 'The effects of Bohm potential on ion-acoustic solitary waves interaction in a nonplanar quantum plasma' [Phys. Plasmas 17, 082307 (2010)

    SciTech Connect

    Akbari-Moghanjoughi, M.

    2010-11-15

    Recently, Li [Phys. Plasmas 17, 082307 (2010)] has studied the effects of Bohm potential on interaction of nonplanar ion-acoustic solitary waves in an unmagnetized electron-positron-ion quantum plasma. In his work the extended reductive perturbation technique has been employed to reduce the basic quantum hydrodynamics plasma equations to Korteweg-de Vries evolution equations (one for each wave) as well as other coupled differential equations describing the phase variation of the resulting solitary waves. The calculated collisional phase-shifts are then numerically evaluated in terms of plasma parameters such as the fractional positron to ion number-density p, relative electron to positron Fermi-temperature {sigma} and the quantum diffraction parameter H. We show that in the chosen plasma model, the parameters p and {sigma} are not independent quantum plasma parameters which has important consequences on the graphical interpretations presented in the mentioned article.

  19. A first approach to the detection and equalization of distorted latent fingerprints and microtraces on non-planar surfaces with confocal laser microscopy

    NASA Astrophysics Data System (ADS)

    Kirst, Stefan; Clausing, Eric; Dittmann, Jana; Vielhauer, Claus

    2012-10-01

    Fingerprints and microtraces play an important role as evidence within the field of criminalistics. Their conservative acquisition processes, are established, but are altering and impurifying the traces often. In case of microtraces even the integrity of the trace complex is affected. Using contactless methods, the acquisition process becomes non-invasiv and repeatable, but might be distorting on the other hand, when non-planar substrates are in use. Detecting and dealing with distortion in contactless aquired scans of non-planar surfaces is a novel field of research. Nowadays highly distorted fingerprints can only be used, if the substrate can be manually distorted by destroying or deforming it. In this paper we suggest methods for detection and equalization of distortion for use in combination of types of traces. Therefore we define different types of distortion in fingerprints and microtraces. A standardization of types is necessary to develop different solution for equalization. For usage within the field of forensics, each method is evaluated via proper error rates and adaptively used to acquire fingerprints and microtraces. Using our techniques, we are able to detect distortion and equalize fingerprints to support the investigators work. In case of microtraces the presented methods can even be used to equalize mircotraces themselves for better determination of their scale and topology. For all scans the confocal 3D laser microscope "Keyence VK-X110" is used to gather color-, intensity- and topography information in 22 different measurement conditions within 6 different samples consisting of a total of 880 scans. Despite our achievements in the field of distortion detection and equalization there are still challenges, like the non-isometric projection, that need to be focused on. Also, the presented equalization methods may not completely remove any kind of distortion, such as added by deformation. Therefore we suggest and discuss future work for improving the

  20. A highway for war and peace: the secretory pathway in plant-microbe interactions.

    PubMed

    Wang, Dong; Dong, Xinnian

    2011-07-01

    Secretion of proteins and other molecules is the primary means by which a cell interacts with its surroundings. The overall organization of the secretory system is remarkably conserved among eukaryotes, and many of the components have been investigated in detail in animal models. Plant cells, because of their sessile lifestyle, are uniquely reliant on the secretory pathway to respond to changes in their environments, either abiotic, such as the absence of nutrients, or biotic, such as the presence of predators or pathogens. In particular, most plant pathogens are extracellular, which demands a robust and efficient host secretory system directed at the site of attack. Here, we present a summary of recent advances in our understanding of the molecular details of the secretory pathway during plant-microbe interactions. Secretion is required not only for the delivery of antimicrobial molecules, but also for the biogenesis of cell surface sensors to detect microbes. The deposition of extracellular material is important in the defense against classical bacterial pathogens as well as in the so-called 'non-host' resistance. Finally, boosting the protein secretion capacity is vital for avoiding infection as well as for achieving symbiosis, even though in the latter case, the microbes are engulfed in intracellular compartments. The emerging evidence indicates that secretion provides an essential interface between plant hosts and their associated microbial partners.

  1. Phosphorylation of αSNAP is Required for Secretory Organelle Biogenesis in Toxoplasma gondii.

    PubMed

    Stewart, Rebecca J; Ferguson, David J P; Whitehead, Lachlan; Bradin, Clare H; Wu, Hong J; Tonkin, Christopher J

    2016-02-01

    Upon infection, apicomplexan parasites quickly invade host cells and begin a replicative cycle rapidly increasing in number over a short period of time, leading to tissue lysis and disease. The secretory pathway of these highly polarized protozoan parasites tightly controls, in time and space, the biogenesis of specialized structures and organelles required for invasion and intracellular survival. In other systems, regulation of protein trafficking can occur by phosphorylation of vesicle fusion machinery. Previously, we have shown that Toxoplasma gondii αSNAP - a protein that controls the disassembly of cis-SNARE complexes--is phosphorylated. Here, we show that this post-translational modification is required for the correct function of αSNAP in controlling secretory traffic. We demonstrate that during intracellular development conditional expression of a non-phosphorylatable form of αSNAP results in Golgi fragmentation and vesiculation of all downstream secretory organelles. In addition, we show that the vestigial plastid (termed apicoplast), although reported not to be reliant on Golgi trafficking for biogenesis, is also affected upon overexpression of αSNAP and is much more sensitive to the levels of this protein than targeting to other organelles. This work highlights the importance of αSNAP and its phosphorylation in Toxoplasma organelle biogenesis and exposes a hereto fore-unexplored mechanism of regulation of vesicle fusion during secretory pathway trafficking in apicomplexan parasites.

  2. Analysis of protein localization and secretory pathway function using the yeast Saccharomyces cerevisiae.

    PubMed

    Vallen, Elizabeth

    2002-01-01

    The isolation and characterization of mutants has been crucial in understanding a number of processes in the field of cell biology. In this exercise, students examine the effects of mutations in the secretory pathway on protein localization. Yeast strains deficient for synthesis of histidinol dehydrogenase are transformed with a plasmid encoding a chimeric protein. The chimera contains a signal sequence fused to histidinol dehydrogenase. A strain with a defect in the translocation of secretory proteins into the endoplasmic reticulum (ER) accumulates sufficient histidinol dehydrogenase in the cytoplasm to grow on media lacking histidine. In contrast, yeast proficient for secretion, or yeast with secretion defects later in the pathway, are unable to grow on media lacking histidine. Student analysis of the experimental yeast transformants and appropriate controls allows investigation into the effects of conditional defects in the secretory pathway on both cell viability and protein localization. The exercise is usually performed in a manner that allows students to execute a number of techniques common in molecular biology laboratories, including plasmid minipreps, restriction digestions, and Southern blots. Student understanding and enjoyment of the exercise was assessed by laboratory reports, oral and written examinations, and questionnaires. After completion of these experiments, students can describe the utility of protein fusions, the roles of mutant analysis in cell biology, and the steps taken by proteins transiting the secretory pathway.

  3. [Immunochemical properties of the excretory-secretory antigen of Trichinella spiralis].

    PubMed

    Akibekov, O S; Lider, L A; Odoevskiĭ, I M; Tokpan, S S; Ospanova, A Z

    2015-01-01

    In vitro cultivation of Trichinella spiralis provided data on the structure of somatic and excretory-secretory antigens of T. spiralis larvae, their immunochemical properties were studied. The findings suggest that work should be continued to produce monoclonal antibodies and to develop highly sensitive and specific ELISA test systems for the diagnosis of human and animal trichinosis. PMID:25850317

  4. Regulated phosphorylation of secretory granule membrane proteins of the rat parotid gland

    SciTech Connect

    Marino, C.R.; Castle, J.D.; Gorelick, F.S. )

    1990-07-01

    An antiserum raised against purified rat parotid secretory granule membrane proteins has been used to identify organelle-specific protein phosphorylation events following stimulation of intact cells from the rat parotid gland. After lobules were prelabeled with ({sup 32}P)orthophosphate and exposed to secretagogues, phosphoproteins were immunoprecipitated with the granule membrane protein antiserum, separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and visualized by autoradiography. Parallel studies of stimulated amylase release were performed. Isoproterenol treatment of parotid lobules resulted in an increase in the phosphate content of immunoprecipitable 60- and 72-kDa proteins that correlated with amylase release in a time-dependent manner. Forskolin addition mimicked these effects, but only the isoproterenol effects were reversed by propranolol treatment. To confirm the specificity of the antiserum to the secretory granule membrane fraction, subcellular isolation techniques were employed following in situ phosphorylation. The 60- and 72-kDa phosphoproteins were immunoprecipitated from both a particulate fraction and a purified secretory granule fraction. Furthermore, the extraction properties of both species suggest that they are integral membrane proteins. These findings support the possibility that stimulus-regulated secretion may involve phosphorylation of integral membrane proteins of the exocrine secretory granule.

  5. Analysis of Protein Localization and Secretory Pathway Function Using the Yeast Saccharomyces cerevisiae

    PubMed Central

    2002-01-01

    The isolation and characterization of mutants has been crucial in understanding a number of processes in the field of cell biology. In this exercise, students examine the effects of mutations in the secretory pathway on protein localization. Yeast strains deficient for synthesis of histidinol dehydrogenase are transformed with a plasmid encoding a chimeric protein. The chimera contains a signal sequence fused to histidinol dehydrogenase. A strain with a defect in the translocation of secretory proteins into the endoplasmic reticulum (ER) accumulates sufficient histidinol dehydrogenase in the cytoplasm to grow on media lacking histidine. In contrast, yeast proficient for secretion, or yeast with secretion defects later in the pathway, are unable to grow on media lacking histidine. Student analysis of the experimental yeast transformants and appropriate controls allows investigation into the effects of conditional defects in the secretory pathway on both cell viability and protein localization. The exercise is usually performed in a manner that allows students to execute a number of techniques common in molecular biology laboratories, including plasmid minipreps, restriction digestions, and Southern blots. Student understanding and enjoyment of the exercise was assessed by laboratory reports, oral and written examinations, and questionnaires. After completion of these experiments, students can describe the utility of protein fusions, the roles of mutant analysis in cell biology, and the steps taken by proteins transiting the secretory pathway. PMID:12669100

  6. Analysis of Protein Localization and Secretory Pathway Function Using the Yeast "Saccharomyces Cerevisiae"

    ERIC Educational Resources Information Center

    Vallen, Elizabeth

    2002-01-01

    The isolation and characterization of mutants has been crucial in understanding a number of processes in the field of cell biology. In this exercise, students examine the effects of mutations in the secretory pathway on protein localization. Yeast strains deficient for synthesis of histidinol dehydrogenase are transformed with a plasmid encoding a…

  7. 21 CFR 866.5380 - Free secretory component immuno-logical test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... system. 866.5380 Section 866.5380 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5380 Free secretory component immuno-logical test system. (a) Identification. A...

  8. 21 CFR 866.5380 - Free secretory component immuno-logical test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... system. 866.5380 Section 866.5380 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5380 Free secretory component immuno-logical test system. (a) Identification. A...

  9. PICK1 Deficiency Impairs Secretory Vesicle Biogenesis and Leads to Growth Retardation and Decreased Glucose Tolerance

    PubMed Central

    Jansen, Anna M.; Jin, Chunyu; Rickhag, Mattias; Lund, Viktor K.; Jensen, Morten; Bhatia, Vikram; Sørensen, Gunnar; Madsen, Andreas N.; Xue, Zhichao; Møller, Siri K.; Woldbye, David; Qvortrup, Klaus; Huganir, Richard; Stamou, Dimitrios; Kjærulff, Ole; Gether, Ulrik

    2013-01-01

    Secretory vesicles in endocrine cells store hormones such as growth hormone (GH) and insulin before their release into the bloodstream. The molecular mechanisms governing budding of immature secretory vesicles from the trans-Golgi network (TGN) and their subsequent maturation remain unclear. Here, we identify the lipid binding BAR (Bin/amphiphysin/Rvs) domain protein PICK1 (protein interacting with C kinase 1) as a key component early in the biogenesis of secretory vesicles in GH-producing cells. Both PICK1-deficient Drosophila and mice displayed somatic growth retardation. Growth retardation was rescued in flies by reintroducing PICK1 in neurosecretory cells producing somatotropic peptides. PICK1-deficient mice were characterized by decreased body weight and length, increased fat accumulation, impaired GH secretion, and decreased storage of GH in the pituitary. Decreased GH storage was supported by electron microscopy showing prominent reduction in secretory vesicle number. Evidence was also obtained for impaired insulin secretion associated with decreased glucose tolerance. PICK1 localized in cells to immature secretory vesicles, and the PICK1 BAR domain was shown by live imaging to associate with vesicles budding from the TGN and to possess membrane-sculpting properties in vitro. In mouse pituitary, PICK1 co-localized with the BAR domain protein ICA69, and PICK1 deficiency abolished ICA69 protein expression. In the Drosophila brain, PICK1 and ICA69 co-immunoprecipitated and showed mutually dependent expression. Finally, both in a Drosophila model of type 2 diabetes and in high-fat-diet-induced obese mice, we observed up-regulation of PICK1 mRNA expression. Our findings suggest that PICK1, together with ICA69, is critical during budding of immature secretory vesicles from the TGN and thus for vesicular storage of GH and possibly other hormones. The data link two BAR domain proteins to membrane remodeling processes in the secretory pathway of peptidergic endocrine

  10. Intracellular calcium signalling in rat parotid acinar cells that lack secretory vesicles.

    PubMed Central

    Liu, P; Scott, J; Smith, P M

    1998-01-01

    Secretory vesicles from pancreatic acinar cells have recently been shown to release Ca2+ after stimulation with Ins(1,4,5)P3 [Gerasimenko, Gerasimenko, Belan and Petersen, (1996) Cell 84, 473-480]. These observations have been used in support of the hypothesis that Ca2+ release from secretory vesicles could be an important component of stimulus secretion coupling in exocrine acinar cells. In the rat, ligation of the parotid duct causes a reversible atrophy of the parotid gland. Most notably, after atrophy the acinar cells are reduced in size and no longer contain secretory vesicles [Liu, Smith, and Scott (1996) J. Dent. Res. 74, 900]. We have measured cytosolic free-Ca2+ concentration ([Ca2+]i) in single, acutely isolated, rat parotid acinar cells, and compared Ca2+ mobilization in response to acetylcholine (ACh) stimulation in cells obtained from control animals to that in cells lacking secretory vesicles obtained after atrophy of the parotid gland. Application of 50-5000 nM ACh to control cells gave rise to a typical, dose-dependent, biphasic increase in [Ca2+]i, of which the later, plateau, phase was acutely dependent on the extracellular Ca2+ concentration. An identical pattern of response was observed with cells obtained from atrophic glands. Low concentrations of ACh (10-100 nM) occasionally produced [Ca2+]i oscillations of a similar pattern in cells from both control and atrophic glands. We were able to show that Ca2+ rises first in the apical pole of the cell and the increase then spreads to the rest of the cell in cells from control glands but not in cells from atrophic glands. However, at present we are unable to determine whether this is due to the lack of secretory vesicles or whether the separation is too small to measure in the smaller acinar cells obtained from atrophic glands. We conclude therefore, that secretory vesicles make no significant contribution to overall Ca2+ mobilization in rat parotid acinar cells, nor are they required for oscillatory

  11. Tracheobronchial epithelium of the sheep: IV. Lectin histochemical characterization of secretory epithelial cells.

    PubMed

    Mariassy, A T; Plopper, C G; St George, J A; Wilson, D W

    1988-09-01

    Conventional histochemical characterization of the mucus secretory apparatus is often difficult to reconcile with the biochemical analysis of respiratory secretions. This study was designed to examine the secretory glycoconjugates in airways using lectins with biochemically defined affinities for main sugar residues of mucus. We used five biotinylated lectins--DBA (Dolichos biflorus) and SBA (Glycine max) for N-acetyl galactosamine (galNAc), BSA I (Bandeiraea simplicifolia) and PNA (Arachis hypogea) for galactose (gal), and UEA I (Ulex europeus)--for detection of fucose (fuc) in HgCl2-fixed, paraffin-embedded, serially sectioned trachea, lobar and segmental bronchi and bronchioles of nine sheep. Lectins selectively localized the carbohydrate residues in luminal secretions, on epithelial cell surfaces, and in secretory cells. In proximal airways, the major carbohydrate residues in luminal secretions, cell surfaces, goblet cells, and glands were fuc and gal-NAc. PNA reacted mainly with apical granules of less than 10% of goblet cells, and gal residues were only detected in some of the mucous cells and on basolateral cell surfaces. Distal airways contained sparse secretion in the lumen, mucous cells contained weakly reactive fuc and gal-NAc, and the epithelial surfaces of Clara cells contained gal. Sugars abundant in the airway secretions were also the major component of cells in glands. We conclude that there is a correlation between specific sugar residues in secretory cells, glycocalyx, and luminal secretions in proximal and distal airways. This suggests that lectins may be used to obtain information about airway secretory cell composition from respiratory secretions. PMID:3189886

  12. Calcium-containing phosphopeptides pave the secretory pathway for efficient protein traffic and secretion in fungi.

    PubMed

    Martín, Juan F

    2014-01-01

    Casein phosphopeptides (CPPs) containing chelated calcium drastically increase the secretion of extracellular homologous and heterologous proteins in filamentous fungi. Casein phosphopeptides released by digestion of alpha - and beta-casein are rich in phosphoserine residues (SerP). They stimulate enzyme secretion in the gastrointestinal tract and enhance the immune response in mammals, and are used as food supplements. It is well known that casein phosphopeptides transport Ca2+ across the membranes and play an important role in Ca2+ homeostasis in the cells. Addition of CPPs drastically increases the production of heterologous proteins in Aspergillus as host for industrial enzyme production. Recent proteomics studies showed that CPPs alter drastically the vesicle-mediated secretory pathway in filamentous fungi, apparently because they change the calcium concentration in organelles that act as calcium reservoirs. In the organelles calcium homeostasis a major role is played by the pmr1 gene, that encodes a Ca2+/Mn2+ transport ATPase, localized in the Golgi complex; this transporter controls the balance between intra-Golgi and cytoplasmic Ca2+ concentrations. A Golgi-located casein kinase (CkiA) governs the ER to Golgi directionality of the movement of secretory proteins by interacting with the COPII coat of secretory vesicles when they reach the Golgi. Mutants defective in the casein-2 kinase CkiA show abnormal targeting of some secretory proteins, including cytoplasmic membrane amino acid transporters that in ckiA mutants are miss-targeted to vacuolar membranes. Interestingly, addition of CPPs increases a glyceraldehyde-3-phpshate dehydrogenase protein that is known to associate with microtubules and act as a vesicle/membrane fusogenic agent. In summary, CPPs alter the protein secretory pathway in fungi adapting it to a deregulated protein traffic through the organelles and vesicles what results in a drastic increase in secretion of heterologous and also of

  13. Unique biological function of cathepsin L in secretory vesicles for biosynthesis of neuropeptides.

    PubMed

    Funkelstein, Lydiane; Beinfeld, Margery; Minokadeh, Ardalan; Zadina, James; Hook, Vivian

    2010-12-01

    Neuropeptides are essential for cell-cell communication in the nervous and neuroendocrine systems. Production of active neuropeptides requires proteolytic processing of proneuropeptide precursors in secretory vesicles that produce, store, and release neuropeptides that regulate physiological functions. This review describes recent findings indicating the prominent role of cathepsin L in secretory vesicles for production of neuropeptides from their protein precursors. The role of cathepsin L in neuropeptide production was discovered using the strategy of activity-based probes for proenkephalin-cleaving activity for identification of the enzyme protein by mass spectrometry. The novel role of cathepsin L in secretory vesicles for neuropeptide production has been demonstrated in vivo by cathepsin L gene knockout studies, cathepsin L gene expression in neuroendocrine cells, and notably, cathepsin L localization in neuropeptide-containing secretory vesicles. Cathepsin L is involved in producing opioid neuropeptides consisting of enkephalin, β-endorphin, and dynorphin, as well as in generating the POMC-derived peptide hormones ACTH and α-MSH. In addition, NPY, CCK, and catestatin neuropeptides utilize cathepsin L for their biosynthesis. The neuropeptide-synthesizing functions of cathepsin L represent its unique activity in secretory vesicles, which contrasts with its role in lysosomes. Interesting evaluations of protease gene knockout studies in mice that lack cathepsin L compared to those lacking PC1/3 and PC2 (PC, prohormone convertase) indicate the key role of cathepsin L in neuropeptide production. Therefore, dual cathepsin L and prohormone convertase protease pathways participate in neuropeptide production. Significantly, the recent new findings indicate cathepsin L as a novel 'proprotein convertase' for production of neuropeptides that mediate cell-cell communication in health and disease.

  14. Tracheobronchial epithelium of the sheep: IV. Lectin histochemical characterization of secretory epithelial cells.

    PubMed

    Mariassy, A T; Plopper, C G; St George, J A; Wilson, D W

    1988-09-01

    Conventional histochemical characterization of the mucus secretory apparatus is often difficult to reconcile with the biochemical analysis of respiratory secretions. This study was designed to examine the secretory glycoconjugates in airways using lectins with biochemically defined affinities for main sugar residues of mucus. We used five biotinylated lectins--DBA (Dolichos biflorus) and SBA (Glycine max) for N-acetyl galactosamine (galNAc), BSA I (Bandeiraea simplicifolia) and PNA (Arachis hypogea) for galactose (gal), and UEA I (Ulex europeus)--for detection of fucose (fuc) in HgCl2-fixed, paraffin-embedded, serially sectioned trachea, lobar and segmental bronchi and bronchioles of nine sheep. Lectins selectively localized the carbohydrate residues in luminal secretions, on epithelial cell surfaces, and in secretory cells. In proximal airways, the major carbohydrate residues in luminal secretions, cell surfaces, goblet cells, and glands were fuc and gal-NAc. PNA reacted mainly with apical granules of less than 10% of goblet cells, and gal residues were only detected in some of the mucous cells and on basolateral cell surfaces. Distal airways contained sparse secretion in the lumen, mucous cells contained weakly reactive fuc and gal-NAc, and the epithelial surfaces of Clara cells contained gal. Sugars abundant in the airway secretions were also the major component of cells in glands. We conclude that there is a correlation between specific sugar residues in secretory cells, glycocalyx, and luminal secretions in proximal and distal airways. This suggests that lectins may be used to obtain information about airway secretory cell composition from respiratory secretions.

  15. Fluoride enhances intracellular degradation of amelogenins during secretory phase of amelogenesis of hamster teeth in organ culture.

    PubMed

    Bronckers, A L J J; Lyaruu, D M; Bervoets, T J M; Wöltgens, J H M

    2002-01-01

    Amelogenins are the major protein species synthesized by secretory ameloblasts and are believed to be involved in enamel mineralization. During enamel formation, amelogenins are progressively degraded into smaller fragments by protease activity. These amelogenin fragments are removed from the enamel extracellular space, thereby enabling full mineralization of the dental enamel. Enamel from fluorotic teeth is porous and contains more proteins and less mineral than sound enamel. In this study we examined the hypothesis that fluoride (F-) is capable of inhibiting the proteolysis of amelogenins in enamel being formed in organ culture. Hamster molar tooth germs in stages of secretory amelogenesis were pulse labeled in vitro with [3H]- or [14C] proline and subsequently pulse chased. The explants were exposed to F- at different days of chase (i.e., during secretory amelogenesis early after labeling, later after labeling or at stages just beyond secretory amelogenesis). Exposure of secretory stage explants to F- enhanced the release of radiolabeled fragments when F- was applied early after labeling but progressively less if applied later. In contrast, F- had no such effect in stages beyond secretion. The enhanced release of radiolabeled fragments in secretory stages was associated with a reduction of radioactivity in the soft tissue enamel organ indicating that fragmentation of enamel matrix proteins (mainly amelogenins) occurred intracellularly. Analysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) demonstrated that the fluorotic enamel contained less radiolabeled parent amelogenins (M(r) 28 kD and 26 kD) but more low-molecular-mass fragments than enamel from control explants. Our data indicate that F- promotes intracellular degradation of the newly synthesized parent amelogenins during secretory stage. Our in vitro data do not support the concept that F- impairs extracellular proteolysis of amelogenins, either in the secretory phase or in the

  16. Fade and tachyphylaxis of gastric acid secretory response to pentagastrin in rat isolated gastric mucosa.

    PubMed

    Hirst, B H; Holland, J; Parsons, M E; Price, C A

    1988-12-01

    1. Gastric acid secretory responses to pentagastrin were characterized in the rat isolated gastric mucosa. In particular, the mechanisms underlying fade, declining response upon continued stimulation, and tachyphylaxis, progressively reduced responses upon repeated stimulation, were investigated. 2. Pentagastrin, 10(-9)-10(-7) M, resulted in concentration-related increases in acid secretion, with a mean maximum of 2.65 mumol cm-2 h-1 in response to pentagastrin, 10(-7) M. Higher concentrations of pentagastrin produced sub-maximal secretory rates; we define this as auto-inhibition. The responses to all concentrations of pentagastrin demonstrated fade. The rate of fade was correlated with the maximum acid secretory rate, declining at about 36% of the peak over the first 16 min. 3. The PO2, PCO2, [HCO3-], pH, [glucose], [lactate], [Na+] and [K+] did not decline during the fade of the acid secretory response to pentagastrin, 10(-7) M. Addition of a second aliquot of pentagastrin was not able to reverse fade, but these tissues were responsive to histamine. Replacement of the serosal solution, before addition of a second aliquot of pentagastrin, increased the acid response from 3% to 24% of the first response. 4. Serosal solution from donor tissues, allowed to respond to pentagastrin and then the acid secretion to fade, was able to stimulate secretion in fresh recipient tissues, although at lower rates. 5. Acid secretory responses to a second dose of pentagastrin were not significantly different, whether the tissues were previously unstimulated, or stimulated with pentagastrin washed out after attaining its peak secretory response (after 10-20 min). The second response was significantly reduced if the first response was allowed to fade with the pentagastrin in contact for 100 min; i.e. fade significantly influenced the extent of tachyphylaxis. 6. Proglumide, 10(-2) M, a gastrin receptor antagonist, and omeprazole, 10(-5) M, an inhibitor of the gastric (H+ + K

  17. Airway Secretory microRNAome Changes during Rhinovirus Infection in Early Childhood

    PubMed Central

    Gutierrez, Maria J.; Gomez, Jose L.; Perez, Geovanny F.; Pancham, Krishna; Val, Stephanie; Pillai, Dinesh K.; Giri, Mamta; Ferrante, Sarah; Freishtat, Robert; Rose, Mary C.; Preciado, Diego; Nino, Gustavo

    2016-01-01

    Background Innate immune responses are fine-tuned by small noncoding RNA molecules termed microRNAs (miRs) that modify gene expression in response to the environment. During acute infections, miRs can be secreted in extracellular vesicles (EV) to facilitate cell-to-cell genetic communication. The purpose of this study was to characterize the baseline population of miRs secreted in EVs in the airways of young children (airway secretory microRNAome) and examine the changes during rhinovirus (RV) infection, the most common cause of asthma exacerbations and the most important early risk factor for the development of asthma beyond childhood. Methods Nasal airway secretions were obtained from children (≤3 yrs. old) during PCR-confirmed RV infections (n = 10) and age-matched controls (n = 10). Nasal EVs were isolated with polymer-based precipitation and global miR profiles generated using NanoString microarrays. We validated our in vivo airway secretory miR data in an in vitro airway epithelium model using apical secretions from primary human bronchial epithelial cells (HBEC) differentiated at air-liquid interface (ALI). Bioinformatics tools were used to determine the unified (nasal and bronchial) signature airway secretory miRNAome and changes during RV infection in children. Results Multiscale analysis identified four signature miRs comprising the baseline airway secretory miRNAome: hsa-miR-630, hsa-miR-302d-3p, hsa- miR-320e, hsa-miR-612. We identified hsa-miR-155 as the main change in the baseline miRNAome during RV infection in young children. We investigated the potential biological relevance of the airway secretion of hsa-mir-155 using in silico models derived from gene datasets of experimental in vivo human RV infection. These analyses confirmed that hsa-miR-155 targetome is an overrepresented pathway in the upper airways of individuals infected with RV. Conclusions Comparative analysis of the airway secretory microRNAome in children indicates that RV infection

  18. A study of the nonlinear aerodynamics of bodies in nonplanar motion. Ph.D. Thesis - Stanford Univ., Calif.; [numerical analysis of aerodynamic force and moment systems during large amplitude, arbitrary motions

    NASA Technical Reports Server (NTRS)

    Schiff, L. B.

    1974-01-01

    Concepts from the theory of functionals are used to develop nonlinear formulations of the aerodynamic force and moment systems acting on bodies in large-amplitude, arbitrary motions. The analysis, which proceeds formally once the functional dependence of the aerodynamic reactions upon the motion variables is established, ensures the inclusion, within the resulting formulation, of pertinent aerodynamic terms that normally are excluded in the classical treatment. Applied to the large-amplitude, slowly varying, nonplanar motion of a body, the formulation suggests that the aerodynamic moment can be compounded of the moments acting on the body in four basic motions: steady angle of attack, pitch oscillations, either roll or yaw oscillations, and coning motion. Coning, where the nose of the body describes a circle around the velocity vector, characterizes the nonplanar nature of the general motion.

  19. Preservation of the secretory response of peritoneal mast cells in the absence of extracellular calcium.

    PubMed

    Bronner, C; Gies, J P; Vallé, A; Landry, Y

    1987-12-01

    The transfer of rat peritoneal mast cells from balanced salt solution to calcium-free buffer led to a time-dependent decrease in their response to compound 48/80 and to ionophore A23187. The concomittant absence of potassium from the calcium-free buffer enabled the mast cells to retain their secretory response. The increase in potassium level, with a parallel decrease in sodium to maintain osmolarity, led to a slight potentiation of the response to 48/80 and to a large but transient potentiation of the response to A23187. Mast cells can be considered nonexcitable. The apparent dependency upon extracellular calcium of mast cell secretory responses might be related to the presumed tight equilibrium between endoplasmic reticulum calcium stores and extracellular calcium. The control of this equilibrium by transmembrane gradients of monovalent ions is proposed. PMID:2446099

  20. A signal sequence is sufficient for green fluorescent protein to be routed to regulated secretory granules.

    PubMed

    El Meskini, R; Jin, L; Marx, R; Bruzzaniti, A; Lee, J; Emeson, R; Mains, R

    2001-02-01

    To investigate trafficking in neuroendocrine cells, green fluorescent protein (GFP) tags were fused to various portions of the preproneuropeptide Y (NPY) precursor. Two neuroendocrine cell lines, AtT-20 corticotrope tumor cells and PC-12 pheochromocytoma cells, along with primary anterior pituitary cells, were examined. Expression of chimeric constructs did not disrupt trafficking or regulated secretion of endogenous ACTH and prohormone convertase 1 in AtT-20 cells. Western blot and immunocytochemical analyses demonstrated that the chimeric constructs remained intact, as long as the Lys-Arg cleavage site within preproNPY was deleted. GFP was stored in, and released from, regulated granules in cells expressing half of the NPY precursor fused to GFP, and also in cells in which only the signal sequence of preproNPY was fused to GFP. Thus, in neuroendocrine cells, entering the lumen of the secretory pathway is sufficient to target GFP to regulated secretory granules.

  1. Secretory vesicle transport velocity in living cells depends on the myosin-V lever arm length.

    PubMed

    Schott, Daniel H; Collins, Ruth N; Bretscher, Anthony

    2002-01-01

    Myosins are molecular motors that exert force against actin filaments. One widely conserved myosin class, the myosin-Vs, recruits organelles to polarized sites in animal and fungal cells. However, it has been unclear whether myosin-Vs actively transport organelles, and whether the recently challenged lever arm model developed for muscle myosin applies to myosin-Vs. Here we demonstrate in living, intact yeast that secretory vesicles move rapidly toward their site of exocytosis. The maximal speed varies linearly over a wide range of lever arm lengths genetically engineered into the myosin-V heavy chain encoded by the MYO2 gene. Thus, secretory vesicle polarization is achieved through active transport by a myosin-V, and the motor mechanism is consistent with the lever arm model.

  2. Serous cutaneous glands in anurans: Fourier transform analysis of the repeating secretory granule substructure

    NASA Astrophysics Data System (ADS)

    Nosi, D.; Delfino, G.; Quercioli, F.

    2013-03-01

    A combined transmission electron microscopy (TEM) and Fourier transform analysis has been performed on the secretory granules storing active peptides/proteins in serous cutaneous glands of n = 12 anuran species. Previous TEM investigation showed that the granules are provided with remarkable repeating substructures based on discrete subunits, arranged into a consistent framework. Furthermore, TEM findings revealed that this recurrent arrangement is acquired during a prolonged post-Golgian (or maturational) processing that affects the secretory product. Maturation leads to a variety of patterns depending on the degree of subunit clustering. This variety of recurrent patterns has been plotted into a range of frequency spectra. Through this quantitative approach, we found that the varying granule substructure can be reduced to a single mechanism of peptide/protein aggregation.

  3. Secretory vesicles transiently dock and fuse at the porosome to discharge contents during cell secretion.

    PubMed

    Jena, Bhanu P

    2009-12-16

    In contrast with the observation in electron micrographs of partially empty vesicles in cells following secretion, it has been believed since the 1950s that during cell secretion, secretory vesicles completely merge at the cell plasma membrane, resulting in the diffusion of intravesicular contents to the cell exterior and the compensatory retrieval of the excess membrane by endocytosis. In the interim, a large body of work has been published arguing both for and against the complete merger of secretory vesicle membrane at the cell plasma membrane during secretion. The only definitive determination of the mechanism of cell secretion remained in its direct observation at nanometre resolution in live cells. In the past decade, this finally became a reality through the power and scope of the atomic force microscope, which has made it possible to resolve a major conundrum in cell biology. This paradigm shift in our understanding of cell secretion is briefly outlined here.

  4. Systems biology of the secretory pathway: what have we learned so far?

    PubMed

    Farhan, Hesso

    2015-07-01

    Several RNAi screens were performed in search for regulators of the secretory pathway. These screens were performed in different organisms and cell lines and relied on different readouts. Therefore, they have only little overlap among their hits, leading to the question of what we have learned from this approach so far and how these screens contributed towards an integrative understanding of the endomembrane system. The aim of this review is to revisit these screens and discuss their strengths and weaknesses as well as potential reasons for their failure to overlap with each other. As with secretory trafficking, RNAi screens were also performed on other cellular processes such as cell migration and autophagy, both of which were shown to be intimately linked to secretion. Another aim of this review is to compare the outcome of the RNAi screens on secretion, autophagy and cell migration and ask whether the functional genomic approaches have uncovered potential mechanistic insights into the links between these processes.

  5. Parallel maturation of the pancreatic secretory response to cholinergic stimulation and the muscarinic receptor population.

    PubMed Central

    Dumont, Y.; Larose, L.; Morisset, J.; Poirier, G. G.

    1981-01-01

    1 The appearance of pancreatic muscarinic receptors during development has been measured by use of the specific ligand [3H]-quinuclidinyl benzilate ([3H]-QNB). 2 QNB binding sites are present in foetal pancreas; their maximal concentration is attained at the age of 30 days and a significant decrease is observed in one year old animals. 3 Affinity of [3H]-QNB for the muscarinic receptor does not change with age. 4 An evaluation of the pancreatic secretory response to a cholinoceptor agonist as a function of age indicates that the development of this response parallels that of the receptor population. 5 It is suggested that, at all ages from 3 days after birth onwards, the maximal secretory response of the exocrine pancreas to a cholinoceptor agonist mobilizes the same proportion of the total population of QNB binding sites. PMID:6165420

  6. Electron microprobe analysis of human labial gland secretory granules in cystic fibrosis

    SciTech Connect

    Izutsu, K.; Johnson, D.; Schubert, M.; Wang, E.; Ramsey, B.; Tamarin, A.; Truelove, E.; Ensign, W.; Young, M.

    1985-06-01

    X-ray microanalysis of freeze-dried labial gland cryosections revealed that Na concentration was doubled and the Ca/S concentration ratio was decreased in secretory granules of labial glands from patients with cystic fibrosis (CF) when compared with glands from normal subjects. Other results suggested that the decrease in the Ca/S concentration ratio resulted from an increase in S concentration. These findings imply that mucous granules in labial saliva showed a CF-related increase in Na and S content, and such changes would be expected to affect the rheology of the mucus after exocytosis. In contrast with a previous study in human parotid glands, no evidence was found for CF-related changes in cytoplasmic or nuclear Na, K, and Ca concentrations. Significant elemental differences were found between secretory granules and nuclei and cytoplasm of control cells.

  7. Secretory breast carcinoma in a 41-year-old man with long-term follow-up: a special report.

    PubMed

    Li, Guanqiao; Zhong, Xiaojie; Yao, Jia; Chen, Jimin; Wang, Mei; Liu, Haiying; Yang, Shiping

    2015-01-01

    Secretory breast carcinoma (SBC) is a rare tumor that is particularly rare in male adults. To our knowledge, only 28 previous male cases of secretory breast carcinoma have been reported. The present a case of secretory breast carcinoma has the longest symptom duration of (40 years) in a male individual until now. Typically, the clinical features and treatment of male SBC are similar with female SBC. The ETV6-NTRK3 fusion gene is a specific genetic alteration in SBC. When compared to other types of male breast cancer, patients with male secretory breast cancer are much younger, and have a lower rate of estrogen/progesterone hormone receptor positivity. Modified radical mastectomy has been favored as a therapeutic approach in all female SBC, male SBC and other types of male breast cancer. [corrected].

  8. Neurexin-1α contributes to insulin-containing secretory granule docking.

    PubMed

    Mosedale, Merrie; Egodage, Sonya; Calma, Rei C; Chi, Nai-Wen; Chessler, Steven D

    2012-02-24

    Neurexins are a family of transmembrane, synaptic adhesion molecules. In neurons, neurexins bind to both sub-plasma membrane and synaptic vesicle-associated constituents of the secretory machinery, play a key role in the organization and stabilization of the presynaptic active zone, and help mediate docking of synaptic vesicles. We have previously shown that neurexins, like many other protein constituents of the neurotransmitter exocytotic machinery, are expressed in pancreatic β cells. We hypothesized that the role of neurexins in β cells parallels their role in neurons, with β-cell neurexins helping to mediate insulin granule docking and secretion. Here we demonstrate that β cells express a more restricted pattern of neurexin transcripts than neurons, with a clear predominance of neurexin-1α expressed in isolated islets. Using INS-1E β cells, we found that neurexin-1α interacts with membrane-bound components of the secretory granule-docking machinery and with the granule-associated protein granuphilin. Decreased expression of neurexin-1α, like decreased expression of granuphilin, reduces granule docking at the β-cell membrane and improves insulin secretion. Perifusion of neurexin-1α KO mouse islets revealed a significant increase in second-phase insulin secretion with a trend toward increased first-phase secretion. Upon glucose stimulation, neurexin-1α protein levels decrease. This glucose-induced down-regulation may enhance glucose-stimulated insulin secretion. We conclude that neurexin-1α is a component of the β-cell secretory machinery and contributes to secretory granule docking, most likely through interactions with granuphilin. Neurexin-1α is the only transmembrane component of the docking machinery identified thus far. Our findings provide new insights into the mechanisms of insulin granule docking and exocytosis.

  9. An Alternative Terminal Step of the General Secretory Pathway in Staphylococcus aureus

    PubMed Central

    Craney, Arryn; Dix, Melissa M.; Adhikary, Ramkrishna; Cravatt, Benjamin F.

    2015-01-01

    ABSTRACT Type I signal peptidase (SPase) is essential for viability in wild-type bacteria because the terminal step of the bacterial general secretory pathway requires its proteolytic activity to release proteins from their membrane-bound N-terminal leader sequences after translocation across the cytoplasmic membrane. Here, we identify the Staphylococcus aureus operon ayrRABC (SA0337 to SA0340) and show that once released from repression by AyrR, the protein products AyrABC together confer resistance to the SPase inhibitor arylomycin M131 by providing an alternate and novel method of releasing translocated proteins. Thus, the derepression of ayrRABC allows cells to bypass the essentiality of SPase. We demonstrate that AyrABC functionally complements SPase by mediating the processing of the normally secreted proteins, albeit in some cases with reduced efficiency and either without cleavage or via cleavage at a site N-terminal to the canonical SPase cleavage site. Thus, ayrRABC encodes a secretion stress-inducible alternate terminal step of the general secretory pathway. Importance  Addressing proteins for proper localization within or outside a cell in both eukaryotes and prokaryotes is often accomplished with intrinsic signals which mediate membrane translocation and which ultimately must be removed. The canonical enzyme responsible for the removal of translocation signals is bacterial type I signal peptidase (SPase), which functions at the terminal step of the general secretory pathway and is thus essential in wild-type bacteria. Here, we identify a four-gene operon in S. aureus that encodes an alternate terminal step of the general secretory pathway and thus makes SPase nonessential. The results have important implications for protein secretion in bacteria and potentially for protein trafficking in prokaryotes and eukaryotes in general. PMID:26286693

  10. Searching for mammary analogue [corrected] secretory carcinoma of salivary gland among its mimics.

    PubMed

    Pinto, Andre; Nosé, Vania; Rojas, Claudia; Fan, Yao-Shan; Gomez-Fernandez, Carmen

    2014-01-01

    Mammary analog secretory carcinoma of salivary gland is a recently described entity with unique morphologic, clinical, and genetic characteristics, including the characteristic t(12;15)(p13;q25) with ETV6-NTRK3 translocation found in secretory carcinomas of the breast. Before their initial description, these salivary gland tumors were generally diagnosed as acinic cell carcinoma or adenocarcinoma. For the purpose of this study, all cases of salivary gland acinic cell carcinoma, cribriform cystadenocarcinoma, and adenocarcinoma, not otherwise specified (NOS), diagnosed over a 10-year period were retrieved from our surgical pathology files. There were a total of 11 cases diagnosed as acinic cell carcinoma, 10 cases of adenocarcinoma, NOS, and 6 cases of cribriform cystadenocarcinoma. All slides were reviewed by two pathologists (AP, CGF) and tumors that show morphologic features of mammary analog secretory carcinoma according to the recent literature were selected. This process narrowed down the initial number to six cases originally diagnosed as acinic cell carcinoma, three cases originally diagnosed as adenocarcinoma, NOS, and one case originally diagnosed as cribriform cystadenocarcinoma. The 10 cases were subjected to immunohistochemistry for S-100, mammaglobin, and ANO1, as well as fluorescence in situ hybridization analysis for t(12;15)(p13;q25) with ETV6-NTRK3 fusion rearrangement. The ETV6-NTRK3 gene rearrangement was detected in three tumors. These three tumors, initially diagnosed as acinic cell carcinomas, stained positive for S-100 and mammaglobin, and negative for ANO1 by immunohistochemistry. Two of the three patients were male (2/3). In summary, mammary analog secretory carcinoma is a newly described diagnostic entity that should be in the differential diagnosis of salivary gland tumors that morphologically mimic other neoplasms, mainly acinic cell carcinomas. They differ from conventional acinic cell tumors immunohistochemically and molecularly

  11. Alteration in Endometrial Proteins during Early- and Mid-Secretory Phases of the Cycle in Women with Unexplained Infertility

    PubMed Central

    Manohar, Murli; Khan, Huma; Sirohi, Vijay Kumar; Das, Vinita; Agarwal, Anjoo; Pandey, Amita; Siddiqui, Waseem Ahmad; Dwivedi, Anila

    2014-01-01

    Background Compromised receptivity of the endometrium is a major cause of unexplained infertility, implantation failure and subclinical pregnancy loss. In order to investigate the changes in endometrial protein profile as a cause of unexplained infertility, the current study was undertaken to analyze the differentially expressed proteins of endometrium from early-secretory (LH+2) to mid-secretory phase (LH+7), in women with unexplained infertility. Methods 2-D gel electrophoresis was performed to analyze the proteomic changes between early- (n = 8) and mid-secretory (n = 8) phase endometrium of women with unexplained infertility. The differentially expressed protein spots were identified by LC-MS analysis and validated by immunoblotting and immuno-histochemical analysis in early- (n = 4) and mid-secretory (n = 4) phase endometrium of infertile women. Validated proteins were also analyzed in early- (n = 4) and mid-secretory (n = 4) phase endometrium of fertile women. Results Nine proteins were found to be differentially expressed between early- and mid- secretory phases of endometrium of infertile women. The expression of Ras-related protein Rap-1b, Protein disulfide isomerase A3, Apolipoprotein-A1 (Apo-A1), Cofilin-1 and RAN GTP-binding nuclear protein (Ran) were found to be significantly increased, whereas, Tubulin polymerization promoting protein family member 3, Superoxide dismutase [Cu-Zn], Sorcin, and Proteasome subunit alpha type-5 were significantly decreased in mid- secretory phase endometrium of infertile women as compared to early-secretory phase endometrium of infertile women. Validation of 4 proteins viz. Sorcin, Cofilin-1, Apo-A1 and Ran were performed in separate endometrial biopsy samples from infertile women. The up-regulated expression of Sorcin and down-regulated expression of Cofilin-1 and Apolipoprotein-A1, were observed in mid-secretory phase as compared to early-secretory phase in case of fertile women. Conclusions De

  12. Differentiation of osmotic and secretory diarrhoea by stool carbohydrate and osmolar gap measurements.

    PubMed

    Castro-Rodríguez, J A; Salazar-Lindo, E; León-Barúa, R

    1997-09-01

    Clinical features and laboratory tests that determine carbohydrate in faeces were evaluated to determine which was best able to distinguish between osmotic and secretory diarrhoea in infants and children. For this purpose 80 boys aged 3 to 24 months, with acute watery diarrhoea, were studied prospectively. The faecal osmolar gap (FOG) was calculated as: serum osmolarity-[2 x (faecal sodium + potassium concentration)]. Fifty eight patients were classified as having predominantly osmotic diarrhoea (FOG > 100 mosmol/l), and 22 as having predominantly secretory diarrhoea (FOG < or = 100 mosmol/l). The two groups were comparable in their clinical features on admission, in the results of blood and urine tests, and in the evolution of their diarrhoeal illness. Evidence of steatorrhoea (by positive Sudan III test) and of acid faecal pH on admission were significantly more frequent in patients with osmotic diarrhoea. Mean (SD) faecal osmolarity was not significantly different between the two groups (319 (80) mosmol/l in secretory diarrhoea v 361 (123) mosmol/l in osmotic diarrhoea). Tests for reducing substances in faeces such as Benedict's test--with and without hydrolysis--and glucose strip, all showed a positive and significant association with osmotic diarrhoea (p < 0.05, < 0.025, < 0.05, respectively). The presence of excess reducing substances (Benedict's test with hydrolysis > 2+) on admission was the most sensitive and specific test with the best predictive value for differentiating between the two types of watery diarrhoea. PMID:9370895

  13. Effect of oral acetylcysteine on tobacco smoke-induced secretory cell hyperplasia.

    PubMed

    Jeffery, P K; Rogers, D F; Ayers, M M

    1985-01-01

    The present investigation explores whether N-acetylcysteine (NAC) inhibits the secretory cell hyperplasia known to occur experimentally in specific pathogen-free (SPF) bronchitic rats. The animals were divided into 4 groups: no tobacco smoke (TS), no drug, no TS but NAC (1040 mg/kg body weight), TS but no drug, and TS plus NAC. NAC-treated animals showed no ill effects, TS exposed animals showed an initial fall in weight gain which never fully recovered (P less than 0.01): NAC did not protect. TS caused a significant increase (62-421%) in secretory cell number at all airway levels distal to the upper trachea (P less than 0.01) and NAC significantly inhibited it (P less than 0.01-0.05) in all, mostly in secretory cells containing acidic glycoprotein. TS exposure also induced a significant rise in epithelial cell concentration and of ciliated, mucous and especially basal cell number (P less than 0.001). NAC inhibited the mucous cell increase (P less than 0.001) and had 3 effects on the peak of dividing cells: it was (a) delayed until 3 days (b) greatly reduced in size and (c) prolonged at a lower level until its return to control values at 10 days of TS exposure. PMID:3862604

  14. Novel N-Benzoyl-2-Hydroxybenzamide Disrupts Unique Parasite Secretory Pathway

    PubMed Central

    Fomovska, Alina; Huang, Qingqing; El Bissati, Kamal; Mui, Ernest J.; Witola, William H.; Cheng, Gang; Zhou, Ying; Sommerville, Caroline; Roberts, Craig W.; Bettis, Sam; Prigge, Sean T.; Afanador, Gustavo A.; Hickman, Mark R.; Lee, Patty J.; Leed, Susan E.; Auschwitz, Jennifer M.; Pieroni, Marco; Stec, Jozef; Muench, Stephen P.; Rice, David W.; Kozikowski, Alan P.

    2012-01-01

    Toxoplasma gondii is a protozoan parasite that can damage the human brain and eyes. There are no curative medicines. Herein, we describe our discovery of N-benzoyl-2-hydroxybenzamides as a class of compounds effective in the low nanomolar range against T. gondii in vitro and in vivo. Our lead compound, QQ-437, displays robust activity against the parasite and could be useful as a new scaffold for development of novel and improved inhibitors of T. gondii. Our genome-wide investigations reveal a specific mechanism of resistance to N-benzoyl-2-hydroxybenzamides mediated by adaptin-3β, a large protein from the secretory protein complex. N-Benzoyl-2-hydroxybenzamide-resistant clones have alterations of their secretory pathway, which traffics proteins to micronemes, rhoptries, dense granules, and acidocalcisomes/plant-like vacuole (PLVs). N-Benzoyl-2-hydroxybenzamide treatment also alters micronemes, rhoptries, the contents of dense granules, and, most markedly, acidocalcisomes/PLVs. Furthermore, QQ-437 is active against chloroquine-resistant Plasmodium falciparum. Our studies reveal a novel class of compounds that disrupts a unique secretory pathway of T. gondii, with the potential to be used as scaffolds in the search for improved compounds to treat the devastating diseases caused by apicomplexan parasites. PMID:22354304

  15. Augmentation of arginase Ⅱ expression in the human endometrial epithelium in the secretory phase.

    PubMed

    Tajima, Makiko; Harada, Tatsuya; Ishikawa, Tomonori; Iwahara, Yuki; Kubota, Toshiro

    2012-01-01

    L-arginine is the common substrate for arginase and nitric oxide synthase (NOS). Arginase converts L-arginine to urea and L-ornithine. L-Ornithine is the principal precursor for the production of polyamines and L-proline, which are required for cell proliferation and collagen synthesis. Endothelial NOS is expressed in the human endometrial glandular epithelium, but the expression and physiological roles of arginase in the human endometrium are not clear. The objective of this study was to investigate the expression and distribution patterns of arginases Ⅰ (A-Ⅰ) and Ⅱ (A-Ⅱ) in the human endometrium by using immunohistochemistry, reverse transcription-polymerase chain reaction (RTPCR), and western blotting. A-Ⅰ and A-Ⅱ were detected by immunohistochemistry in human endometrial epithelial cells during the proliferative and secretory phases of the menstrual cycle. RT-PCR showed that A-Ⅰ and A-Ⅱ mRNA were expressed in human endometrial tissue. Western blotting analysis results showed the expression of A-Ⅱ protein. Immunohistochemistry and western blotting results showed that expression levels of A-Ⅱ were significantly higher in the secretory phase than in the proliferative phase. Increased A-Ⅱ levels in the secretory phase may be responsible for endometrial growth by increasing polyamines and proline products. PMID:23897115

  16. Tracking individual secretory vesicles during exocytosis reveals an ordered and regulated process

    PubMed Central

    Donovan, Kirk W.

    2015-01-01

    Post-Golgi secretory vesicle trafficking is a coordinated process, with transport and regulatory mechanisms to ensure appropriate exocytosis. While the contributions of many individual regulatory proteins to this process are well studied, the timing and dependencies of events have not been defined. Here we track individual secretory vesicles and associated proteins in vivo during tethering and fusion in budding yeast. Secretory vesicles tether to the plasma membrane very reproducibly for ∼18 s, which is extended in cells defective for membrane fusion and significantly lengthened and more variable when GTP hydrolysis of the exocytic Rab is delayed. Further, the myosin-V Myo2p regulates the tethering time in a mechanism unrelated to its interaction with exocyst component Sec15p. Two-color imaging of tethered vesicles with Myo2p, the GEF Sec2p, and several exocyst components allowed us to document a timeline for yeast exocytosis in which Myo2p leaves 4 s before fusion, whereas Sec2p and all the components of the exocyst disperse coincident with fusion. PMID:26169352

  17. Novel N-benzoyl-2-hydroxybenzamide disrupts unique parasite secretory pathway.

    PubMed

    Fomovska, Alina; Huang, Qingqing; El Bissati, Kamal; Mui, Ernest J; Witola, William H; Cheng, Gang; Zhou, Ying; Sommerville, Caroline; Roberts, Craig W; Bettis, Sam; Prigge, Sean T; Afanador, Gustavo A; Hickman, Mark R; Lee, Patty J; Leed, Susan E; Auschwitz, Jennifer M; Pieroni, Marco; Stec, Jozef; Muench, Stephen P; Rice, David W; Kozikowski, Alan P; McLeod, Rima

    2012-05-01

    Toxoplasma gondii is a protozoan parasite that can damage the human brain and eyes. There are no curative medicines. Herein, we describe our discovery of N-benzoyl-2-hydroxybenzamides as a class of compounds effective in the low nanomolar range against T. gondii in vitro and in vivo. Our lead compound, QQ-437, displays robust activity against the parasite and could be useful as a new scaffold for development of novel and improved inhibitors of T. gondii. Our genome-wide investigations reveal a specific mechanism of resistance to N-benzoyl-2-hydroxybenzamides mediated by adaptin-3β, a large protein from the secretory protein complex. N-Benzoyl-2-hydroxybenzamide-resistant clones have alterations of their secretory pathway, which traffics proteins to micronemes, rhoptries, dense granules, and acidocalcisomes/plant-like vacuole (PLVs). N-Benzoyl-2-hydroxybenzamide treatment also alters micronemes, rhoptries, the contents of dense granules, and, most markedly, acidocalcisomes/PLVs. Furthermore, QQ-437 is active against chloroquine-resistant Plasmodium falciparum. Our studies reveal a novel class of compounds that disrupts a unique secretory pathway of T. gondii, with the potential to be used as scaffolds in the search for improved compounds to treat the devastating diseases caused by apicomplexan parasites.

  18. Giant secretory granules in the ducts of the parotid and submandibular glands of the slow loris.

    PubMed

    Tandler, B; Pinkstaff, C A; Nagato, T; Phillips, C J

    1996-06-01

    The parotid and submandibular glands of a slow loris, a rare Southeast Asian primate, were obtained after the head had been perfused by fixative for a study of the brain. These tissues were processed by conventional means for electron microscopy. Glands also were obtained at autopsy from 2 other lorises, fixed by immersion in formalin, and subjected to a battery of tests for glycoconjugates. In the parotid gland, a short segment of the proximal striated duct lacks both basal striations and any sign of secretory activity. The major portion of the striated duct consists of tall cells that contain a spectrum of secretory granules, some larger than the nuclei (many granules are > 9 mum in diameter). These granules, which are delimited by a single membrane, are capable of chain exocytosis. Many of the giant granules have bundles of cytofilaments (4.5-6.5 nm) in apparent association with their surface. Occasional cells contain numerous small granules. Duct cells with or without granules lack basal striations. The granules contain neutral glycoconjugates but no acidic glycoconjugates. Some, but not all, interlobular excretory ducts also have secretory granules that run the gamut from tiny to giant. Exactly the same situation occurs in the submandibular gland. Unlike other primates, which may have duct cells that contain only a few tiny granules in their apices, the cells in both the striated and excretory ducts in the slow loris appear to be specialized for secretion rather than for transport. The biofunction of the giant granules is unknown.

  19. The structure and dynamics of secretory component and its interactions with polymeric immunoglobulins.

    PubMed

    Stadtmueller, Beth M; Huey-Tubman, Kathryn E; López, Carlos J; Yang, Zhongyu; Hubbell, Wayne L; Bjorkman, Pamela J

    2016-01-01

    As a first-line vertebrate immune defense, the polymeric immunoglobulin receptor (pIgR) transports polymeric IgA and IgM across epithelia to mucosal secretions, where the cleaved ectodomain (secretory component; SC) becomes a component of secretory antibodies, or when unliganded, binds and excludes bacteria. Here we report the 2.6Å crystal structure of unliganded human SC (hSC) and comparisons with a 1.7Å structure of teleost fish SC (tSC), an early pIgR ancestor. The hSC structure comprises five immunoglobulin-like domains (D1-D5) arranged as a triangle, with an interface between ligand-binding domains D1 and D5. Electron paramagnetic resonance measurements confirmed the D1-D5 interface in solution and revealed that it breaks upon ligand binding. Together with binding studies of mutant and chimeric SCs, which revealed domain contributions to secretory antibody formation, these results provide detailed models for SC structure, address pIgR evolution, and demonstrate that SC uses multiple conformations to protect mammals from pathogens. PMID:26943617

  20. Secretory response induced by essential oils on airway surface fluid: a pharmacological MRI study.

    PubMed

    Nicolato, Elena; Boschi, Federico; Marzola, Pasquina; Sbarbati, Andrea

    2009-07-30

    Using pharmacological magnetic resonance imaging, we have performed an in vivo evaluation of the secretory response induced by essential oils in the rat airway. Aim of the work was to establish a computerized method to assess the efficacy of volatile compounds in spatially localized areas without the bias derived by subjective evaluation. Magnetic resonance experiments were carried out using a 4.7 T horizontal magnet. In the trachea, airway surface fluid was easily identified for its high intensity signal. The tracheal glands were also easily visible. The oesophageal lumen was usually collapsed and was identifiable only in the presence of intraluminal liquid. Scotch pine essential oil inhalation significantly increased the surface fluid in the middle portion of the trachea and the increase was visible at both 5 and 10 min. A lesser secretory response was detected after rosemary essential oil inhalation even though the response was significant with respect to the control in particular at 10 min. No secretory response was detected after peppermint essential oil inhalation both at 5 and 10 min. The data obtained in the present work demonstrate a chemically induced airway secretion. The availability of a pharmacological magnetic resonance imaging approach opens new perspectives to test the action of volatile compounds on the airway. PMID:19422906

  1. Intracellular and transcellular transport of secretory and membrane proteins in the rat hepatocyte

    SciTech Connect

    Sztul, E.S.

    1984-01-01

    The intra- and transcellular transport of hepatic secretory and membrane proteins was studied in rats in vivo using (/sup 3/H)fucose and (/sup 35/S)cyteine as metabolic precursors. Incorporated radioactivity in plasma, bile, and liver subcellular fractions was measured and the labeled proteins of the Golgi complex, bile and plasma were separated by SDS-PAGE and identified by fluorography. /sup 3/H-radioactivity in Golgi fractions peaked at 10 min post injection (p.i.) and then declined concomitantly with the appearance of labeled glycoproteins in plasma. Maximal secretion of secretory fucoproteins from the Golgi complex occurred between 10 and 20 min p.i. In contrast, the clearance of labeled proteins from Golgi membrane subfractions occurred past 30 min p.i., indicating that membrane proteins leave the Golgi complex at least 10 min later than the bulk of content proteins. A major 80K form of Secretory Component (SC) was identified in the bile by precipitation with an anti IgA antibody. A comparative study of kinetics of transport of /sup 35/S-labeled SC and /sup 35/S-labeled albumin showed that albumin peaked in bile at approx.45 min p.i., whereas the SC peak occurred at 80 min p.i., suggesting that the transit time differs for plasma and membrane proteins which are delivered to the bile canaliculus (BC).

  2. A pediatric case of mammary analogue secretory carcinoma within the parotid.

    PubMed

    Quattlebaum, S Craig; Roby, Brianne; Dishop, Megan K; Said, M Sherif; Chan, Kenny

    2015-01-01

    Mammary analogue secretory carcinoma (MASC) is a recently described entity in the differential diagnosis of salivary gland tumors. It is notable for a characteristic t(12;15)(p13;q25) translocation that results in a unique fusion protein, ETV6-NTRK3. While several studies have retrospectively identified this translocation in cases previously diagnosed as a different salivary malignancy, there have been relatively few cases where this translocation was identified on initial pathology results, and fewer still in a pediatric population. We present a case of a 15 year old female with a slowly enlarging, painless, left facial mass. MRI demonstrated a cystic mass extending into the deep lobe of the parotid, and she underwent parotidectomy. The tumor cells stained positive for S100 and CK19. ETV6 translocation was present, confirming the diagnosis. Mammary analogue secretory carcinoma is a recently described tumor of the salivary glands, which often masquerades as more common primary salivary gland tumors and cysts. More research is needed to characterize the typical behavior of this neoplasm and the optimal treatment regimen. With identification of its characteristic translocation, mammary analogue secretory carcinoma can be easily differentiated from its more prevalent counterparts, and should therefore remain within the differential of the pathologist and head and neck surgeon. PMID:26545463

  3. Effect of oral acetylcysteine on tobacco smoke-induced secretory cell hyperplasia.

    PubMed

    Jeffery, P K; Rogers, D F; Ayers, M M

    1985-01-01

    The present investigation explores whether N-acetylcysteine (NAC) inhibits the secretory cell hyperplasia known to occur experimentally in specific pathogen-free (SPF) bronchitic rats. The animals were divided into 4 groups: no tobacco smoke (TS), no drug, no TS but NAC (1040 mg/kg body weight), TS but no drug, and TS plus NAC. NAC-treated animals showed no ill effects, TS exposed animals showed an initial fall in weight gain which never fully recovered (P less than 0.01): NAC did not protect. TS caused a significant increase (62-421%) in secretory cell number at all airway levels distal to the upper trachea (P less than 0.01) and NAC significantly inhibited it (P less than 0.01-0.05) in all, mostly in secretory cells containing acidic glycoprotein. TS exposure also induced a significant rise in epithelial cell concentration and of ciliated, mucous and especially basal cell number (P less than 0.001). NAC inhibited the mucous cell increase (P less than 0.001) and had 3 effects on the peak of dividing cells: it was (a) delayed until 3 days (b) greatly reduced in size and (c) prolonged at a lower level until its return to control values at 10 days of TS exposure.

  4. Differentiation of osmotic and secretory diarrhoea by stool carbohydrate and osmolar gap measurements

    PubMed Central

    Castro-Rodriguez, J. A.; Salazar-Lindo, E.; Leon-Barua, R.

    1997-01-01

    

 Clinical features and laboratory tests that determine carbohydrate in faeces were evaluated to determine which was best able to distinguish between osmotic and secretory diarrhoea in infants and children. For this purpose 80 boys aged 3 to 24 months, with acute watery diarrhoea, were studied prospectively. The faecal osmolar gap (FOG) was calculated as: serum osmolarity − [2 × (faecal sodium + potassium concentration)]. Fifty eight patients were classified as having predominantly osmotic diarrhoea (FOG >100 mosmol/l), and 22 as having predominantly secretory diarrhoea (FOG ⩽100 mosmol/l). The two groups were comparable in their clinical features on admission, in the results of blood and urine tests, and in the evolution of their diarrhoeal illness. Evidence of steatorrhoea (by positive Sudan III test) and of acid faecal pH on admission were significantly more frequent in patients with osmotic diarrhoea. Mean (SD) faecal osmolarity was not significantly different between the two groups (319 (80) mosmol/l in secretory diarrhoea v 361 (123) mosmol/l in osmotic diarrhoea). Tests for reducing substances in faeces such as Benedict's test—with and without hydrolysis—and glucose strip, all showed a positive and significant association with osmotic diarrhoea (p <0.05, <0.025, <0.05, respectively). The presence of excess reducing substances (Benedict's test with hydrolysis >++) on admission was the most sensitive and specific test with the best predictive value for differentiating between the two types of watery diarrhoea.

 PMID:9370895

  5. The structure and dynamics of secretory component and its interactions with polymeric immunoglobulins

    PubMed Central

    Stadtmueller, Beth M; Huey-Tubman, Kathryn E; López, Carlos J; Yang, Zhongyu; Hubbell, Wayne L; Bjorkman, Pamela J

    2016-01-01

    As a first-line vertebrate immune defense, the polymeric immunoglobulin receptor (pIgR) transports polymeric IgA and IgM across epithelia to mucosal secretions, where the cleaved ectodomain (secretory component; SC) becomes a component of secretory antibodies, or when unliganded, binds and excludes bacteria. Here we report the 2.6Å crystal structure of unliganded human SC (hSC) and comparisons with a 1.7Å structure of teleost fish SC (tSC), an early pIgR ancestor. The hSC structure comprises five immunoglobulin-like domains (D1-D5) arranged as a triangle, with an interface between ligand-binding domains D1 and D5. Electron paramagnetic resonance measurements confirmed the D1-D5 interface in solution and revealed that it breaks upon ligand binding. Together with binding studies of mutant and chimeric SCs, which revealed domain contributions to secretory antibody formation, these results provide detailed models for SC structure, address pIgR evolution, and demonstrate that SC uses multiple conformations to protect mammals from pathogens. DOI: http://dx.doi.org/10.7554/eLife.10640.001 PMID:26943617

  6. Cysteine-Rich Atrial Secretory Protein from the Snail Achatina achatina: Purification and Structural Characterization

    PubMed Central

    Shabelnikov, Sergey; Kiselev, Artem

    2015-01-01

    Despite extensive studies of cardiac bioactive peptides and their functions in molluscs, soluble proteins expressed in the heart and secreted into the circulation have not yet been reported. In this study, we describe an 18.1-kDa, cysteine-rich atrial secretory protein (CRASP) isolated from the terrestrial snail Achatina achatina that has no detectable sequence similarity to any known protein or nucleotide sequence. CRASP is an acidic, 158-residue, N-glycosylated protein composed of eight alpha-helical segments stabilized with five disulphide bonds. A combination of fold recognition algorithms and ab initio folding predicted that CRASP adopts an all-alpha, right-handed superhelical fold. CRASP is most strongly expressed in the atrium in secretory atrial granular cells, and substantial amounts of CRASP are released from the heart upon nerve stimulation. CRASP is detected in the haemolymph of intact animals at nanomolar concentrations. CRASP is the first secretory protein expressed in molluscan atrium to be reported. We propose that CRASP is an example of a taxonomically restricted gene that might be responsible for adaptations specific for terrestrial pulmonates. PMID:26444993

  7. Secretory proteins in the reproductive tract of the snapping turtle, Chelhydra serpentina.

    PubMed

    Mahmoud, I Y; Paulson, J R; Dudley, M; Patzlaff, J S; Al-Kindi, A Y A

    2004-12-01

    SDS-polyacrylamide gel electrophoresis was used to separate the secretory proteins produced by the epithelial and endometrial glands of the uterine tube and uterus in the snapping turtle Chelydra serpentina. The proteins were analyzed throughout the phases of the reproductive cycle from May to August, including preovulatory, ovulatory, postovulatory or luteal, and vitellogenic phases. The pattern of secretory proteins is quite uniform along the length of the uterine tube, and the same is true of the uterus, but the patterns for uterine tube and uterus are clearly different. We identify 13 major proteins in C. serpentina egg albumen. Bands co-migrating with 11 of these are found in the uterine tube, but at most 4 are found in the uterus, suggesting that the majority of the albumen proteins are most likely secreted in the uterine tube, not in the uterus. Although some of the egg albumen proteins are present in the uterine tube only at the time of ovulation, most of the bands corresponding to albumen proteins are present throughout the breeding season even though the snapping turtle is a monoclutch species. These results suggest that the glandular secretory phase in the uterine tube is active and quite homogeneous in function regardless of location or phase of the reproductive cycle. PMID:15596394

  8. Circadian pancreatic enzyme pattern and relationship between secretory and motor activity in fasting humans.

    PubMed

    Keller, Jutta; Layer, Peter

    2002-08-01

    It is unknown whether nonparallel pancreatic enzyme output occurs under basal conditions in humans. We aimed to determine whether the circadian or wake-sleep cycle influences the relationship among pancreatic enzymes or between pancreatic secretory and jejunal motor activity. Using orojejunal multilumen intubation, we measured enzyme outputs and proximal jejunal motility index during consecutive daytime and nighttime periods in each of seven fasting, healthy volunteers. Enzyme outputs were correlated tightly during daytime phases of wakefulness and nighttime phases of sleep (r > 0.72, P < 0.001). During nocturnal phases of wakefulness, output of proteases (r = 0.84, P < 0.001), but not of amylase and trypsin (r = 0.12), remained associated. Nocturnally, particularly during sleep, pancreatic secretory activity was directly correlated with jejunal motility index (r > 0.50, P < 0.001). In conclusion, parallel secretion of pancreatic enzymes dominates throughout the circadian cycle. Nonparallel secretion during nocturnal phases of wakefulness may be due to merely circadian effects or to the coupling of the wake-sleep and the circadian cycle. The association between fluctuations of secretory and motor activity appears to be particularly tight during the night.

  9. Zinc in Specialized Secretory Tissues: Roles in the Pancreas, Prostate, and Mammary Gland12

    PubMed Central

    Kelleher, Shannon L.; McCormick, Nicholas H.; Velasquez, Vanessa; Lopez, Veronica

    2011-01-01

    Zinc (Zn) is an essential micronutrient required for over 300 different cellular processes, including DNA and protein synthesis, enzyme activity, and intracellular signaling. Cellular Zn homeostasis necessitates the compartmentalization of Zn into intracellular organelles, which is tightly regulated through the integration of Zn transporting mechanisms. The pancreas, prostate, and mammary gland are secretory tissues that have unusual Zn requirements and thus must tightly regulate Zn metabolism through integrating Zn import, sequestration, and export mechanisms. Recent findings indicate that these tissues utilize Zn for basic cellular processes but also require Zn for unique cellular needs. In addition, abundant Zn is transported into the secretory pathway and a large amount is subsequently secreted in a tightly regulated manner for unique biological processes. Expression of numerous members of the SLC30A (ZnT) and SLC39A (Zip) gene families has been documented in these tissues, yet there is limited understanding of their precise functional role in Zn metabolism or their regulation. Impairments in Zn secretion from the pancreas, prostate, and mammary gland are associated with disorders such as diabetes, infertility, and cancer, respectively. In this review, we will provide a brief summary of the specific role of Zn in each tissue and describe our current knowledge regarding how Zn metabolism is regulated. Finally, in each instance, we will reflect upon how this information shapes our current understanding of the role of Zn in these secretory tissues with respect to human health and disease. PMID:22332039

  10. Copper, zinc and calcium: imaging and quantification in anterior pituitary secretory granules.

    PubMed

    Bonnemaison, Mathilde L; Duffy, Megan E; Mains, Richard E; Vogt, Stefan; Eipper, Betty A; Ralle, Martina

    2016-09-01

    The anterior pituitary is specialized for the synthesis, storage and release of peptide hormones. The activation of inactive peptide hormone precursors requires a specific set of proteases and other post-translational processing enzymes. High levels of peptidylglycine α-amidating monooxygenase (PAM), an essential peptide processing enzyme, occur in the anterior pituitary. PAM, which converts glycine-extended peptides into amidated products, requires copper and zinc to support its two catalytic activities and calcium for structure. We used X-ray fluorescence microscopy on rat pituitary sections and inductively coupled plasma mass spectrometry on subcellular fractions prepared from rat anterior pituitary to localize and quantify copper, zinc and calcium. X-ray fluorescence microscopy indicated that the calcium concentration in pituitary tissue was about 2.5 mM, 10-times more than zinc and 50-times more than copper. Although no higher than cytosolic levels, secretory granule levels of copper exceeded PAM levels by a factor of 10. Atp7a, which transports copper into the lumen of the secretory pathway, was enriched in endosomes and Golgi, not in secretory granules. If Atp7a transfers copper directly to PAM, this pH-dependent process is likely to occur in Golgi and endosomes. PMID:27426256

  11. The key target of neuroprotection after the onset of ischemic stroke: secretory pathway Ca2+-ATPase 1

    PubMed Central

    Li, Li-hua; Tian, Xiang-rong; Hu, Zhi-ping

    2015-01-01

    The regulatory mechanisms of cytoplasmic Ca2+ after myocardial infarction-induced Ca2+ overload involve secretory pathway Ca2+-ATPase 1 and the Golgi apparatus and are well understood. However, the effect of Golgi apparatus on Ca2+ overload after cerebral ischemia and reperfusion remains unclear. Four-vessel occlusion rats were used as animal models of cerebral ischemia. The expression of secretory pathway Ca2+-ATPase 1 in the cortex and hippocampus was detected by immunoblotting, and Ca2+ concentrations in the cytoplasm and Golgi vesicles were determined. Results showed an overload of cytoplasmic Ca2+ during ischemia and reperfusion that reached a peak after reperfusion. Levels of Golgi Ca2+ showed an opposite effect. The expression of Golgi-specific secretory pathway Ca2+-ATPase 1 in the cortex and hippocampus decreased before ischemia and reperfusion, and increased after reperfusion for 6 hours. This variation was similar to the alteration of calcium in separated Golgi vesicles. These results indicate that the Golgi apparatus participates in the formation and alleviation of calcium overload, and that secretory pathway Ca2+-ATPase 1 tightly responds to ischemia and reperfusion in nerve cells. Thus, we concluded that secretory pathway Ca2+-ATPase 1 plays an essential role in cytosolic calcium regulation and its expression can be used as a marker of Golgi stress, responding to cerebral ischemia and reperfusion. The secretory pathway Ca2+-ATPase 1 can be an important neuroprotective target of ischemic stroke. PMID:26487855

  12. Myosin Va facilitates the distribution of secretory granules in the F-actin rich cortex of PC12 cells.

    PubMed

    Rudolf, Rüdiger; Kögel, Tanja; Kuznetsov, Sergei A; Salm, Thorsten; Schlicker, Oliver; Hellwig, Andrea; Hammer, John A; Gerdes, Hans-Hermann

    2003-04-01

    Neuroendocrine secretory granules, the storage organelles for neuropeptides and hormones, are formed at the trans-Golgi network, stored inside the cell and exocytosed upon stimulation. Previously, we have reported that newly formed secretory granules of PC12 cells are transported in a microtubule-dependent manner from the trans-Golgi network to the F-actin-rich cell cortex, where they undergo short directed movements and exhibit a homogeneous distribution. Here we provide morphological and biochemical evidence that myosin Va is associated with secretory granules. Expression of a dominant-negative tail domain of myosin Va in PC12 cells led to an extensive clustering of secretory granules close to the cell periphery, a loss of their cortical restriction and a strong reduction in their motility in the actin cortex. Based on this data we propose a model that implies a dual transport system for secretory granules: after microtubule-dependent delivery to the cell periphery, secretory granules exhibit a myosin Va-dependent transport leading to their restriction and even dispersal in the F-actin-rich cortex of PC12 cells. PMID:12615975

  13. Engineering of a Secretory Active Three-Dimensional Lacrimal Gland Construct on the Basis of Decellularized Lacrimal Gland Tissue.

    PubMed

    Spaniol, Kristina; Metzger, Marco; Roth, Mathias; Greve, Burkhard; Mertsch, Sonja; Geerling, Gerd; Schrader, Stefan

    2015-10-01

    Lacrimal gland (LG) insufficiency is a main cause for severe dry eye leading to pain, visual impairment, and eventually loss of sight. Engineering of transplantable LG tissue with secretory capacity is a desirable goal. In this study, a three-dimensional decellularized LG (DC-LG) scaffold with preserved LG morphology was generated by treatment with 1% sodium deoxycholate and DNase solution using porcine LG tissue. To address clinical applicability, the primary in vitro culture of secretory active LG cells from a small tissue biopsy of 1.5 mm diameter was introduced and compared with an established isolation method by enzymatic digestion. Cells from both isolation methods depicted an epithelial phenotype, maintained their secretory capacity for up to 30 days, and exhibited progenitor cell capacity as measured by aldehyde dehydrogenase-1 activity, side population assay, and colony-forming units. Cells from passage 0 were reseeded into the DC-LG and secretory active cells migrated into the tissue. The cells resembled an LG-like morphology and the constructs showed secretory activity. These results demonstrate the possibility of engineering a secretory competent, three-dimensional LG construct using LG cells expanded from a small tissue biopsy and DC-LG as a matrix that provides the native structure and physiological niche for these cells.

  14. Relationship between high-frequency radiation and asperity ruptures, revealed by hybrid back-projection with a non-planar fault model.

    PubMed

    Okuwaki, Ryo; Yagi, Yuji; Hirano, Shiro

    2014-01-01

    High-frequency seismic waves are generated by abrupt changes of rupture velocity and slip-rate during an earthquake. Therefore, analysis of high-frequency waves is crucial to understanding the dynamic rupture process. Here, we developed a hybrid back-projection method that considers variations in focal mechanisms by introducing a non-planar fault model that reflects the subducting slab geometry. We applied it to teleseismic P-waveforms of the Mw 8.8 2010 Chile earthquake to estimate the spatiotemporal distribution of high-frequency (0.5-2.0 Hz) radiation. By comparing the result with the coseismic slip distribution obtained by waveform inversion, we found that strong high-frequency radiation can precede and may trigger a large asperity rupture. Moreover, in between the large slip events, high-frequency radiation of intermediate strength was concentrated along the rupture front. This distribution suggests that by bridging the two large slips, this intermediate-strength high-frequency radiation might play a key role in the interaction of the large slip events. PMID:25406638

  15. Non-planar ion-acoustic solitary waves and their head-on collision in a plasma with nonthermal electrons and warm adiabatic ions

    SciTech Connect

    Han Jiuning; He Yonglin; Chen Yan; Zhang Kezhi; Ma Baohong

    2013-01-15

    By using the model of Cairns et al.[Geophys. Rev. Lett. 22, 2709 (1995)], the head-on collision of cylindrical/spherical ion-acoustic solitary waves in an unmagnetized non-planar plasma consisting of warm adiabatic ions and nonthermally distributed electrons is investigated. The extended Poincare-Lighthill-Kuo perturbation method is used to derive the modified Korteweg-de Vries equations for ion-acoustic solitary waves in this plasma system. The effects of the plasma geometry m, the ion to electron temperature ratio {sigma}, and the nonthermality of the electron distribution {alpha} on the interaction of the colliding solitary waves are studied. It is found that the plasma geometries have a big impact on the phase shifts of solitary waves. Also it is important to note that the phase shifts induced by the collision of compressive and rarefactive solitary waves are very different. We point out that this study is useful to the investigations about the observations of electrostatic solitary structures in astrophysical as well as in experimental plasmas with nonthermal energetic electrons.

  16. Relationship between High-frequency Radiation and Asperity Ruptures, Revealed by Hybrid Back-projection with a Non-planar Fault Model

    NASA Astrophysics Data System (ADS)

    Okuwaki, Ryo; Yagi, Yuji; Hirano, Shiro

    2014-11-01

    High-frequency seismic waves are generated by abrupt changes of rupture velocity and slip-rate during an earthquake. Therefore, analysis of high-frequency waves is crucial to understanding the dynamic rupture process. Here, we developed a hybrid back-projection method that considers variations in focal mechanisms by introducing a non-planar fault model that reflects the subducting slab geometry. We applied it to teleseismic P-waveforms of the Mw 8.8 2010 Chile earthquake to estimate the spatiotemporal distribution of high-frequency (0.5-2.0 Hz) radiation. By comparing the result with the coseismic slip distribution obtained by waveform inversion, we found that strong high-frequency radiation can precede and may trigger a large asperity rupture. Moreover, in between the large slip events, high-frequency radiation of intermediate strength was concentrated along the rupture front. This distribution suggests that by bridging the two large slips, this intermediate-strength high-frequency radiation might play a key role in the interaction of the large slip events.

  17. Relationship between High-frequency Radiation and Asperity Ruptures, Revealed by Hybrid Back-projection with a Non-planar Fault Model

    PubMed Central

    Okuwaki, Ryo; Yagi, Yuji; Hirano, Shiro

    2014-01-01

    High-frequency seismic waves are generated by abrupt changes of rupture velocity and slip-rate during an earthquake. Therefore, analysis of high-frequency waves is crucial to understanding the dynamic rupture process. Here, we developed a hybrid back-projection method that considers variations in focal mechanisms by introducing a non-planar fault model that reflects the subducting slab geometry. We applied it to teleseismic P-waveforms of the Mw 8.8 2010 Chile earthquake to estimate the spatiotemporal distribution of high-frequency (0.5–2.0 Hz) radiation. By comparing the result with the coseismic slip distribution obtained by waveform inversion, we found that strong high-frequency radiation can precede and may trigger a large asperity rupture. Moreover, in between the large slip events, high-frequency radiation of intermediate strength was concentrated along the rupture front. This distribution suggests that by bridging the two large slips, this intermediate-strength high-frequency radiation might play a key role in the interaction of the large slip events. PMID:25406638

  18. Tissue distribution of co-planar and non-planar tetra- and hexa-chlorobiphenyl isomers in guinea pigs after oral ingestion

    SciTech Connect

    Jan, J.; Logar, B.; Jan, J.

    1996-03-01

    Food ingestion is the most important route for the uptake of lipophilic organochlorine contaminants. Uptake and transfer of the contaminants from the digestive tract to target organs can be used for risk evaluation. The bioconcentration and migration of polychlorobiphenyls (PCBs) is highly structure - dependent. Bioconcentration is correlated with lipophilicity on the basis of the n-octanol/water partition coefficient in its logarithmic form - logKow. However, some factors e.g. diffusion through cell membranes, accumulation in specific organs and tissues, uptake and deputation kinetics and metabolism can also influence the bioconcentration. Individual PCB compounds of commercial PCB preparation are taken up by organisms to markedly different extents. Until now little is known about the distribution of non-planar and co-planar PCBs in different tissues. Co-planar PCBs have dioxin - like toxicity. This study examines differences in the bioconcentration of two pairs of tetra and hexa chlorobiphenyls from the digestive tract and their distribution in different tissues of guinea pigs.

  19. Nonplanar Method for Predicting Incompressible Aerodynamic Coefficients of Rectangular Wings with Circular-Arc Camber. Ph.D. Thesis - Virginia Polytechnic Institute

    NASA Technical Reports Server (NTRS)

    Lamar, J. E.

    1971-01-01

    The development of a nonplanar lifting surface method having a continuous distribution of singularities and satisfying the tangent flow boundary condition on the mean camber surface is given. The method predicts some incompressible longitudinal aerodynamic coefficients of rectangular wings which have circular-arc camber. The solution method is of the integral-equation type and the resulting surface integrals are evaluated by either using numerical or analytical techniques, as are appropriate. Applications are made and the results compared with those from an exact two-dimensional circular-arc camber solution, a three-dimensional flat-wing solution which represents the camber by a projected slope onto the flat surface, and a flat-wing experiment. From these comparisons, the present method is found to predict well the flat-wing experiment and limiting values, in addition to the center of pressure variation at an angle of attack of zero for any camber. For wings having camber ratios larger than about 1.25% and moderate to high aspect ratios, the results deterioriate due to the inadequacy of lifting pressure modes employed.

  20. Ranking Gene Ontology terms for predicting non-classical secretory proteins in eukaryotes and prokaryotes.

    PubMed

    Huang, Wen-Lin

    2012-11-01

    Protein secretion is an important biological process for both eukaryotes and prokaryotes. Several sequence-based methods mainly rely on utilizing various types of complementary features to design accurate classifiers for predicting non-classical secretory proteins. Gene Ontology (GO) terms are increasing informative in predicting protein functions. However, the number of used GO terms is often very large. For example, there are 60,020 GO terms used in the prediction method Euk-mPLoc 2.0 for subcellular localization. This study proposes a novel approach to identify a small set of m top-ranked GO terms served as the only type of input features to design a support vector machine (SVM) based method Sec-GO to predict non-classical secretory proteins in both eukaryotes and prokaryotes. To evaluate the Sec-GO method, two existing methods and their used datasets are adopted for performance comparisons. The Sec-GO method using m=436 GO terms yields an independent test accuracy of 96.7% on mammalian proteins, much better than the existing method SPRED (82.2%) which uses frequencies of tri-peptides and short peptides, secondary structure, and physicochemical properties as input features of a random forest classifier. Furthermore, when applying to Gram-positive bacterial proteins, the Sec-GO with m=158 GO terms has a test accuracy of 94.5%, superior to NClassG+ (90.0%) which uses SVM with several feature types, comprising amino acid composition, di-peptides, physicochemical properties and the position specific weighting matrix. Analysis of the distribution of secretory proteins in a GO database indicates the percentage of the non-classical secretory proteins annotated by GO is larger than that of classical secretory proteins in both eukaryotes and prokaryotes. Of the m top-ranked GO features, the top-four GO terms are all annotated by such subcellular locations as GO:0005576 (Extracellular region). Additionally, the method Sec-GO is easily implemented and its web tool of

  1. Distinct Molecular Events during Secretory Granule Biogenesis Revealed by Sensitivities to Brefeldin A

    PubMed Central

    Fernandez, Carlos J.; Haugwitz, Michael; Eaton, Benjamin; Moore, Hsiao-Ping H.

    1997-01-01

    The biogenesis of peptide hormone secretory granules involves a series of sorting, modification, and trafficking steps that initiate in the trans-Golgi and trans-Golgi network (TGN). To investigate their temporal order and interrelationships, we have developed a pulse–chase protocol that follows the synthesis and packaging of a sulfated hormone, pro-opiomelanocortin (POMC). In AtT-20 cells, sulfate is incorporated into POMC predominantly on N-linked endoglycosidase H-resistant oligosaccharides. Subcellular fractionation and pharmacological studies confirm that this sulfation occurs at the trans-Golgi/TGN. Subsequent to sulfation, POMC undergoes a number of molecular events before final storage in dense-core granules. The first step involves the transfer of POMC from the sulfation compartment to a processing compartment (immature secretory granules, ISGs): Inhibiting export of pulse-labeled POMC by brefeldin A (BFA) or a 20°C block prevents its proteolytic conversion to mature adrenocorticotropic hormone. Proteolytic cleavage products were found in vesicular fractions corresponding to ISGs, suggesting that the processing machinery is not appreciably activated until POMC exits the sulfation compartment. A large portion of the labeled hormone is secreted from ISGs as incompletely processed intermediates. This unregulated secretory process occurs only during a limited time window: Granules that have matured for 2 to 3 h exhibit very little unregulated release, as evidenced by the efficient storage of the 15-kDa N-terminal fragment that is generated by a relatively late cleavage event within the maturing granule. The second step of granule biogenesis thus involves two maturation events: proteolytic activation of POMC in ISGs and a transition of the organelle from a state of high unregulated release to one that favors intracellular storage. By using BFA, we show that the two processes occurring in ISGs may be uncoupled: although the unregulated secretion from ISGs is

  2. Wide distribution of cysteine-rich secretory proteins in snake venoms: isolation and cloning of novel snake venom cysteine-rich secretory proteins.

    PubMed

    Yamazaki, Yasuo; Hyodo, Fumiko; Morita, Takashi

    2003-04-01

    Cysteine-rich secretory proteins (CRISPs) are found in epididymis and granules of mammals, and they are thought to function in sperm maturation and in the immune system. Recently, we isolated and obtained clones for novel snake venom proteins that are classified as CRISP family proteins. To elucidate the distribution of snake venom CRISP family proteins, we evaluated a wide range of venoms for immuno-cross-reactivity. Then we isolated, characterized, and cloned genes for three novel CRISP family proteins (piscivorin, ophanin, and catrin) from the venom of eastern cottonmouth (Agkistrodon piscivorus piscivorus), king cobra (Ophiophagus hannah), and western diamondback rattlesnake (Crotalus atrox). Our results show the wide distribution of snake venom CRISP family proteins among Viperidae and Elapidae from different continents, indicating that CRISP family proteins compose a new group of snake venom proteins. PMID:12646276

  3. Microtubules and protein secretion in rat lacrimal glands: localization of short-term effects of colchicine on the secretory process

    PubMed Central

    1982-01-01

    The pathway and kinetics of the secretory protein transport in rat lacrimal exorbital gland have been established by an in vitro time- course radioautographic study of pulse-labeled protein secretion. The colchicine-sensitive steps have been localized by using the drug at various times with respect to the pulse labeling of proteins. Colchicine (10 microM) does not block any step of the secretory protein transport, but when introduced before the pulse it decreases the transfer of labeled proteins from the rough endoplasmic reticulum to the Golgi area, suppressing their temporary accumulation in the Golgi area before any alteration of this organelle is detectable. Moreover, colchicine inhibits protein release only from the secretory granules formed in its presence because the peroxidase discharge is diminished 1 h after colchicine addition, and the secretion of newly synthesized proteins is strongly inhibited only when colchicine is introduced before secretory granule formation. Morphometric studies show that there is a great increase of secondary lysosomes, related to crinophagy, as early as 40-50 min after colchicine is added. However, changes in lysosomal enzymatic activities remained biochemically undetectable. We conclude that: (a) the labile microtubular system does not seem indispensable for protein transport in the rough endoplasmic reticulum-Golgi area but may facilitate this step, perhaps by maintaining the spatial organization of this area; and (b) in the lacrimal gland, colchicine inhibits protein release not by acting on the steps of secretion following the secretory granule formation, but by acting chiefly on the steps preceding secretory granule formation, perhaps by making the secretory granules formed in its presence incapable of discharging their content. PMID:7142282

  4. Antigenic homogeneity of male Müllerian gland (MG) secretory proteins of a caecilian amphibian with secretory proteins of the mammalian prostate gland and seminal vesicles: evidence for role of the caecilian MG as a male accessory reproductive gland.

    PubMed

    Radha, Arumugam; Sree, Sreesha; Faisal, Kunnathodi; Kumar, G Pradeep; Oommen, Oommen V; Akbarsha, Mohammad A

    2014-10-01

    Whereas in all other vertebrates the Müllerian ducts of genetic males are aborted during development, under the influence of Müllerian-inhibiting substance, in the caecilian amphibians they are retained as a pair of functional glands. It has long been speculated that the Müllerian gland might be the male accessory reproductive gland but there has been no direct evidence to this effect. The present study was undertaken to determine whether the caecilian Müllerian gland secretory proteins would bear antigenic similarity to secretory proteins of the prostate gland and/or the seminal vesicles of a mammal. The secretory proteins of the Müllerian gland of Ichthyophis tricolor were evaluated for cross-reactivity with antisera raised against rat ventral prostate and seminal vesicle secretory proteins, adopting SDS-PAGE, two-dimensional electrophoresis and immunoblot techniques. Indeed there was a cross-reaction of five Müllerian gland secretory protein fractions with prostatic protein antiserum and of three with seminal vesicle protein antiserum. A potential homology exists because in mammals the middle group of the prostate primordia is derived from a diverticulum of the Müllerian duct. Thus this study, by providing evidence for expression of prostatic and seminal vesicle proteins in the Müllerian gland, substantiates the point that in caecilians the Müllerian glands are the male accessory reproductive glands.

  5. Antigenic homogeneity of male Müllerian gland (MG) secretory proteins of a caecilian amphibian with secretory proteins of the mammalian prostate gland and seminal vesicles: evidence for role of the caecilian MG as a male accessory reproductive gland.

    PubMed

    Radha, Arumugam; Sree, Sreesha; Faisal, Kunnathodi; Kumar, G Pradeep; Oommen, Oommen V; Akbarsha, Mohammad A

    2014-10-01

    Whereas in all other vertebrates the Müllerian ducts of genetic males are aborted during development, under the influence of Müllerian-inhibiting substance, in the caecilian amphibians they are retained as a pair of functional glands. It has long been speculated that the Müllerian gland might be the male accessory reproductive gland but there has been no direct evidence to this effect. The present study was undertaken to determine whether the caecilian Müllerian gland secretory proteins would bear antigenic similarity to secretory proteins of the prostate gland and/or the seminal vesicles of a mammal. The secretory proteins of the Müllerian gland of Ichthyophis tricolor were evaluated for cross-reactivity with antisera raised against rat ventral prostate and seminal vesicle secretory proteins, adopting SDS-PAGE, two-dimensional electrophoresis and immunoblot techniques. Indeed there was a cross-reaction of five Müllerian gland secretory protein fractions with prostatic protein antiserum and of three with seminal vesicle protein antiserum. A potential homology exists because in mammals the middle group of the prostate primordia is derived from a diverticulum of the Müllerian duct. Thus this study, by providing evidence for expression of prostatic and seminal vesicle proteins in the Müllerian gland, substantiates the point that in caecilians the Müllerian glands are the male accessory reproductive glands. PMID:25160003

  6. Ca(2+)-calmodulin-dependent phosphorylation of islet secretory granule proteins

    SciTech Connect

    Watkins, D.T. )

    1991-08-01

    The effect of Ca2+ and calmodulin on phosphorylation of islet secretory granule proteins was studied. Secretory granules were incubated in a phosphorylation reaction mixture containing (32P)ATP and test reagents. The 32P-labeled proteins were resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the 32P content was visualized by autoradiography, and the relative intensities of specific bands were quantitated. When the reaction mixture contained EGTA and no added Ca2+, 32P was incorporated into two proteins with molecular weights of 45,000 and 13,000. When 10(-4) M Ca2+ was added without EGTA, two additional proteins (58,000 and 48,000 Mr) were phosphorylated, and the 13,000-Mr protein was absent. The addition of 2.4 microM calmodulin markedly enhanced the phosphorylation of the 58,000- and 48,000-Mr proteins and resulted in the phosphorylation of a major protein whose molecular weight (64,000 Mr) is identical to that of one of the calmodulin binding proteins located on the granule surface. Calmodulin had no effect on phosphorylation in the absence of Ca2+ but was effective in the presence of calcium between 10 nM and 50 microM. Trifluoperazine and calmidazolium, calmodulin antagonists, produced a dose-dependent inhibition of the calmodulin effect. 12-O-tetradecanoylphorbol 13-acetate, a phorbol ester that activates protein kinase C, produced no increase in phosphorylation, and 1-(5-isoquinoline sulfonyl)-2-methyl piperazine dihydrochloride, an inhibitor of protein kinase C, had no effect. These results indicate that Ca(2+)-calmodulin-dependent protein kinases and endogenous substrates are present in islet secretory granules.

  7. Leptin secretory dynamics and associated disordered eating psychopathology across the weight spectrum

    PubMed Central

    Baskaran, Charumathi; Eddy, Kamryn T.; Miller, Karen K.; Meenaghan, Erinne; Misra, Madhusmita; Lawson, Elizabeth A.

    2016-01-01

    Leptin secretory dynamics across the weight spectrum and their relationship with disordered eating psychopathology have not been studied. Our objective was to compare leptin secretory dynamics in 13 anorexia nervosa (AN), 12 overweight/obese (OB) and 12 normal-weight women using deconvolution analysis. Methods In this cross-sectional study conducted at a tertiary referral center, serum leptin levels were obtained every 20 minutes from 2000-0800h. Dual energy X-ray absorptiometry was used to measure %body fat. Disordered eating psychopathology was assessed by the Eating Disorders Examination-Questionnaire (EDE-Q) and Eating Disorders Inventory-2 (EDI-2). Results The groups differed for basal leptin secretion (BASAL) (p=0.02). Mean leptin pulse amplitude, pulse mass, total pulsatile secretion (TPS) and area under the curve (AUC) were significantly different between groups before and after adjustment for BASAL (p<0.0001 for all). Leptin AUC correlated strongly with TPS (r=0.97, p<0.0001) and less with BASAL (r=0.35, p=0.03). On multivariate analysis, only TPS was a significant predictor of leptin AUC (p<0.0001). TPS was inversely associated with most EDE-Q and EDI-2 parameters and the associations remained significant for EDE-Q eating concern (p=0.01), and EDI-2 asceticism, ineffectiveness and social insecurity (p<0.05) after adjusting for BASAL. These relationships were not significant when controlled for %body fat. Conclusion Secretory dynamics of leptin differ across weight spectrum, with mean pulse amplitude, mean pulse mass and TPS being low in AN and high in OB. Pulsatile, rather than basal secretion, is the major contributor to leptin AUC. Decreased pulsatile leptin is associated with disordered eating psychopathology, possibly reflecting low %body fat in AN. PMID:26903591

  8. Secretory clusterin inhibits osteoclastogenesis by attenuating M-CSF-dependent osteoclast precursor cell proliferation

    SciTech Connect

    Choi, Bongkun; Kang, Soon-Suk; Kang, Sang-Wook; Min, Bon-Hong; Lee, Eun-Jin; Song, Da-Hyun; Kim, Sang-Min; Song, Youngsup; Yoon, Seung-Yong; Chang, Eun-Ju

    2014-07-18

    Highlights: • We describe the expression and secretion of clusterin in osteoclasts. • Endogenous clusterin deficiency does not affect osteoclast formation. • Exogenous treatment with secretory clusterin decreases osteoclast differentiation. • Secretory clusterin attenuates osteoclast precursor cell proliferation by inhibiting M-CSF-mediated ERK activation. - Abstract: Secretory clusterin (sCLU)/apolipoprotein J is a multifunctional glycoprotein that is ubiquitously expressed in various tissues. Reduced sCLU in the joints of patients with bone erosive disease is associated with disease activity; however, its exact role has yet to be elucidated. Here, we report that CLU is expressed and secreted during osteoclastogenesis in mouse bone marrow-derived macrophages (BMMs) that are treated with receptor activator of nuclear factor kappa-B ligand (RANKL) and macrophage colony-stimulating factor (M-CSF). CLU-deficient BMMs obtained from CLU{sup −/−} mice exhibited no significant alterations in OC differentiation in comparison with BMMs obtained from wild-type mice. In contrast, exogenous sCLU treatment significantly inhibited OC formation in both BMMs and OC precursor cultures. The inhibitory effect of sCLU was more prominent in BMMs than OC precursor cultures. Interestingly, treating BMMs with sCLU decreased the proliferative effects elicited by M-CSF and suppressed M-CSF-induced ERK activation of OC precursor cells without causing apoptotic cell death. This study provides the first evidence that sCLU reduces OC formation by inhibiting the actions of M-CSF, thereby suggesting its protective role in bone erosion.

  9. [Effect of plant hormones on the components of secretory pathway in human normal and tumor cells].

    PubMed

    Vil'danova, M S; Savitskaia, M A; Onishchenko, G E; Smirnova, E A

    2014-01-01

    Plant hormones play a key role in plant growth and differentiation. Many hormones are known as potential antitumor agents, yet others appear to affect the secretory activity and are produced by mammalian cells as pro-inflammatory cytokines. The goal of this research was to study the effect of abscisic and gibberellic acids on the secretory system of human cultured epidermoid carcinoma cells A431 and keratinocytes HaCat. Immunocytochemical and morphometric analysis demonstrated that subtoxic concentration of plant hormones induced the broadening of the ER network and increased the size of Golgi complex. Electron microscopy studies confirmed the hypertrophic changes of the Golgi apparatus, specifically, the swelling of cisternae in the trans-compartment of dictyosomes after exposure to abscisic acid, and swelling of cis- and trans-compartment of dictyosomes after exposure to abscisic acid, and swelling of cis- and trans-compartments of dictyosomes after exposure to gibberellic acid. Using of Click-iT technique allowed to detect the elevation of the total protein synthesis only in A431 cells exposed to abscisic acid. Cumulative data suggests that, under these conditions, the hypertrophy of Golgi apparatus may reflect the enhanced secretory activity of cells. In other experiments, the hypertrophy of Golgi is not related to increased protein synthesis and therefore may suggest the stress-related changes of ER and Golgi apparatus. Our results demonstrate that morphologically similar reaction of cellular organelles, such as hypertrophy of Golgi apparatus, is the result of different functional activities, and that molecular mechanisms underlying the changes induced in cells need further investigations. PMID:25696996

  10. Tracheal and bronchial polymeric immunoglobulin secretory immune system (PISIS) development in a porcine model.

    PubMed

    Guzman-Bautista, E R; Ramirez-Estudillo, M C; Rojas-Gomez, O I; Vega-Lopez, M A

    2015-12-01

    Polymeric immunoglobulins (pIgs) mucosal secretion is mediated by the pIg secretory immune system (PISIS), which is composed of J-chain (JC) and antibody (IgM/IgA) producing cells (JC-AbPC), pIg receptor (pIgR) epithelial cell expression and the efficient release of secretory Igs (SIgs) to the mucosal lumen. A poor development or disturbances in this system may cause higher infection susceptibility, as observed in young and elderly people. In spite of this system's importance, few detailed studies regarding its development have been described in the lower respiratory tract of humans. Because the porcine model has been reported as an option for translational medicine to humans, we studied the tracheal and bronchial PISIS development in healthy, non-vaccinated, SPF, miniature Vietnamese pigs from birth to adulthood using immunohistochemistry and ELISAs. Our results demonstrated that pIgR was present at birth, and its expression increased with age. In contrast, JC-AbPC were low in neonatal pigs; however, colostrum was a source of IgM, SIgA, total IgA and IgG in respiratory secretions (trachea and bronchoalveolar lavages, nasal secretion and saliva) in piglets. JC-AbPC steadily increased in post-weaned, young and adult pigs, correlating with considerable increases in secretory and total Igs in the trachea and bronchi. These data suggest a compensatory role of maternal Igs at the respiratory mucosa in the absence of a structured PISIS before weaning. Furthermore, monomeric Igs (IgG and IgA) may also play an important role in respiratory protection and deserves a more thorough study. PMID:26188097

  11. Axons provide the secretory machinery for trafficking of voltage-gated sodium channels in peripheral nerve.

    PubMed

    González, Carolina; Cánovas, José; Fresno, Javiera; Couve, Eduardo; Court, Felipe A; Couve, Andrés

    2016-02-16

    The regulation of the axonal proteome is key to generate and maintain neural function. Fast and slow axoplasmic waves have been known for decades, but alternative mechanisms to control the abundance of axonal proteins based on local synthesis have also been identified. The presence of the endoplasmic reticulum has been documented in peripheral axons, but it is still unknown whether this localized organelle participates in the delivery of axonal membrane proteins. Voltage-gated sodium channels are responsible for action potentials and are mostly concentrated in the axon initial segment and nodes of Ranvier. Despite their fundamental role, little is known about the intracellular trafficking mechanisms that govern their availability in mature axons. Here we describe the secretory machinery in axons and its contribution to plasma membrane delivery of sodium channels. The distribution of axonal secretory components was evaluated in axons of the sciatic nerve and in spinal nerve axons after in vivo electroporation. Intracellular protein trafficking was pharmacologically blocked in vivo and in vitro. Axonal voltage-gated sodium channel mRNA and local trafficking were examined by RT-PCR and a retention-release methodology. We demonstrate that mature axons contain components of the endoplasmic reticulum and other biosynthetic organelles. Axonal organelles and sodium channel localization are sensitive to local blockade of the endoplasmic reticulum to Golgi transport. More importantly, secretory organelles are capable of delivering sodium channels to the plasma membrane in isolated axons, demonstrating an intrinsic capacity of the axonal biosynthetic route in regulating the axonal proteome in mammalian axons. PMID:26839409

  12. Axons provide the secretory machinery for trafficking of voltage-gated sodium channels in peripheral nerve

    PubMed Central

    González, Carolina; Cánovas, José; Fresno, Javiera; Couve, Eduardo; Court, Felipe A.; Couve, Andrés

    2016-01-01

    The regulation of the axonal proteome is key to generate and maintain neural function. Fast and slow axoplasmic waves have been known for decades, but alternative mechanisms to control the abundance of axonal proteins based on local synthesis have also been identified. The presence of the endoplasmic reticulum has been documented in peripheral axons, but it is still unknown whether this localized organelle participates in the delivery of axonal membrane proteins. Voltage-gated sodium channels are responsible for action potentials and are mostly concentrated in the axon initial segment and nodes of Ranvier. Despite their fundamental role, little is known about the intracellular trafficking mechanisms that govern their availability in mature axons. Here we describe the secretory machinery in axons and its contribution to plasma membrane delivery of sodium channels. The distribution of axonal secretory components was evaluated in axons of the sciatic nerve and in spinal nerve axons after in vivo electroporation. Intracellular protein trafficking was pharmacologically blocked in vivo and in vitro. Axonal voltage-gated sodium channel mRNA and local trafficking were examined by RT-PCR and a retention-release methodology. We demonstrate that mature axons contain components of the endoplasmic reticulum and other biosynthetic organelles. Axonal organelles and sodium channel localization are sensitive to local blockade of the endoplasmic reticulum to Golgi transport. More importantly, secretory organelles are capable of delivering sodium channels to the plasma membrane in isolated axons, demonstrating an intrinsic capacity of the axonal biosynthetic route in regulating the axonal proteome in mammalian axons. PMID:26839409

  13. Regulation by L channels of Ca(2+)-evoked secretory responses in ouabain-treated chromaffin cells.

    PubMed

    De Pascual, Ricardo; Colmena, Inés; Ruiz-Pascual, Lucía; Baraibar, Andrés Mateo; Egea, Javier; Gandía, Luis; García, Antonio G

    2016-10-01

    It is known that the sustained depolarisation of adrenal medullary bovine chromaffin cells (BCCs) with high K(+) concentrations produces an initial sharp catecholamine release that subsequently fades off in spite depolarisation persists. Here, we have recreated a sustained depolarisation condition of BCCs by treating them with the Na(+)/K(+) ATPase blocker ouabain; in doing so, we searched experimental conditions that permitted the development of a sustained long-term catecholamine release response that could be relevant during prolonged stress. BCCs were perifused with nominal 0Ca(2+) solution, and secretion responses were elicited by intermittent application of short 2Ca(2+) pulses (Krebs-HEPES containing 2 mM Ca(2+)). These pulses elicited a biphasic secretory pattern with an initial 30-min period with secretory responses of increasing amplitude and a second 30-min period with steady-state, non-inactivating responses. The initial phase was not due to gradual depolarisation neither to gradual increases of the cytosolic calcium transients ([Ca(2+)]c) elicited by 2Ca(2+) pulses in BBCs exposed to ouabain; both parameters increased soon after ouabain addition. Νifedipine blocked these responses, and FPL64176 potentiated them, suggesting that they were triggered by Ca(2+) entry through non-inactivating L-type calcium channels. This was corroborated by nifedipine-evoked blockade of the L-type Ca(2+) channel current and the [Ca(2+)]c transients elicited by 2Ca(2+) pulses. Furthermore, the plasmalemmal Na(+)/Ca(2+) exchanger (NCX) blocker SEA0400 caused a mild inhibition followed by a large rebound increase of the steady-state secretory responses. We conclude that these two phases of secretion are mostly contributed by Ca(2+) entry through L calcium channels, with a minor contribution of Ca(2+) entry through the reverse mode of the NCX.

  14. Growth-induced non-planar magnetic anisotropy in FeCoZr-CaF{sub 2} nanogranular films: Structural and magnetic characterization

    SciTech Connect

    Kasiuk, J. V.; Fedotova, J. A.; Przewoznik, J. Zukrowski, J.; Sikora, M.; Kapusta, Cz.; Grce, A.; Milosavljević, M.

    2014-07-28

    The relation between nanoscale structure, local atomic order and magnetic properties of (FeCoZr){sub x}(CaF{sub 2}){sub 100−x} (29 ≤ x ≤ 73 at. %) granular films is studied as a function of metal/insulator fraction ratio. The films of a thickness of 1–6 μm were deposited on Al-foils and glass-ceramic substrates, by ion sputtering of targets of different metal/insulator contents. Structural characterization with X-ray and electron diffraction as well as transmission electron microscopy revealed that the films are composed of isolated nanocrystalline bcc α-FeCo(Zr) alloy and insulating fcc CaF{sub 2} matrix. They grow in a columnar structure, where elongated metallic nanograins are arranged on top of each other within the columns almost normal to the substrate surface. Mössbauer spectroscopy and magnetometry results indicate that their easy magnetization axes are oriented at an angle of 65°–74° to the surface in films with x between 46 and 74, above the electrical percolation threshold, which is attributed to the growth-induced shape anisotropy. Interatomic distances characteristic for metallic state of α-FeCo(Zr) nanograins were revealed by X-ray Absorption Spectroscopy. The results show a lack of surface oxidation of the alloy nanograins, so the growth-induced orientation of nanograins in the films cannot be attributed to this effect. The study is among the first to report a growth-induced non-planar magnetic anisotropy in metal/insulator granular films above the percolation threshold and to reveal the origin of it.

  15. Fast Domain Partitioning Method for dynamic boundary integral equations applicable to non-planar faults dipping in 3-D elastic half-space

    NASA Astrophysics Data System (ADS)

    Ando, Ryosuke

    2016-11-01

    The elastodynamic boundary integral equation method (BIEM) in real space and in the temporal domain is an accurate semi-analytical tool to investigate the earthquake rupture dynamics on non-planar faults. However, its heavy computational demand for a historic integral generally increases with a time complexity of O(MN3)for the number of time steps N and elements M due to volume integration in the causality cone. In this study, we introduce an efficient BIEM, termed the `Fast Domain Partitioning Method' (FDPM), which enables us to reduce the computation time to the order of the surface integral, O(MN2), without degrading the accuracy. The memory requirement is also reduced to O(M2) from O(M2N). FDPM uses the physical nature of Green's function for stress to partition the causality cone into the domains of the P and S wave fronts, the domain in-between the P and S wave fronts, and the domain of the static equilibrium, where the latter two domains exhibit simpler dependences on time and/or space. The scalability of this method is demonstrated on the large-scale parallel computing environments of distributed memory systems. It is also shown that FDPM enables an efficient use of memory storage, which makes it possible to reduce computation times to a previously unprecedented level. We thus present FDPM as a powerful tool to break through the current fundamental difficulties in running dynamic simulations of coseismic ruptures and earthquake cycles under realistic conditions of fault geometries.

  16. Are there salvage routes within the general secretory pathway in yeast?

    PubMed

    Gozalbo, D; Martínez, J P; Sentandreu, R

    1992-04-01

    It is generally accepted that both extracellular protein secretion and plasma membrane expansion in yeast occur basically as in higher eukaryotic cells. In addition to the constitutive (default) secretory pathway, some specialized mammalian cells possess a regulated route which at present has not been detected in yeast. However, there is a body of experimental results suggesting that under certain circumstances export of integral plasma membrane and exocellular proteins may take place through alternative (salvage) pathways. The existence of these latter routes would enable the yeast cell to adapt more efficiently to distinct or adverse conditions requiring the secretion of discrete amounts of specific sets of proteins.

  17. Stimulus-secretion coupling in the developing exocrine pancreas: secretory responsiveness to cholecystokinin

    PubMed Central

    1986-01-01

    We have studied the onset of secretory responsiveness to cholecystokinin (CCK) during development of the rat exocrine pancreas. Although acinar cells of the fetal pancreas (1 d before birth) are filled with zymogen granules containing the secretory protein, alpha- amylase, the rate of amylase secretion from pancreatic lobules incubated in vitro was not increased in response to CCK. In contrast, the rate of CCK-stimulated amylase discharge from the neonatal pancreas (1 d after birth) was increased four- to eightfold above that of the fetal gland. The postnatal amplification of secretory responsiveness was not associated with an increase in the number or cell surface expression of 125I-CCK binding sites. When 125I-CCK-33 binding proteins were analyzed by affinity crosslinking, two proteins of Mr 210,000 and 100,000-160,000 were labeled specifically in both fetal and neonatal pancreas. To determine if cell surface receptors for CCK in the fetal pancreas are functional and able to generate a rise in the cytosolic [Ca++], we measured 45Ca++ efflux from tracer-loaded lobules. 45Ca++ efflux from both fetal and neonatal pancreas was comparably increased by CCK, indicating CCK-induced Ca++ mobilization and elevated cytosolic [Ca++]. The Ca++ ionophore A23187 also stimulated the rate of 45Ca++ extrusion from pancreas of both ages. Increased amylase secretion occurred concurrently with A23187-stimulated 45Ca++ efflux in neonatal pancreas, but not in the fetal gland. A23187 in combination with dibutyryl cAMP potentiated amylase release from the neonatal gland, but not from fetal pancreas. Similarly, the protein kinase C activator, phorbol dibutyrate, did not increase the rate of secretion from the fetal gland when added alone or in combination with A23187 or CCK. We suggest that CCK-receptor interaction in the fetal pancreas triggers intracellular Ca++ mobilization. However, one or more signal transduction events distal to Ca++ mobilization have not yet matured. The onset of

  18. Protein modifications in the plant secretory pathway: current status and practical implications in molecular pharming.

    PubMed

    Faye, Loïc; Boulaflous, Aurelia; Benchabane, Meriem; Gomord, Véronique; Michaud, Dominique

    2005-03-01

    Plants have become, over the last ten years, a suitable alternative to microbial and animal cell factories for the production of clinically-useful, therapeutic proteins. Besides the well known advantage of low-cost and large-scale production of safe and biologically active mammalian proteins, plants also are able to perform most post-translational maturations required for biological activity and suitable pharmacokinetics of recombinant therapeutic proteins. In this short review we focus on glycosylation and proteolytic processing of plant-made pharmaceuticals during their transport through the plant cell's secretory pathway. We also address the practical implications of these important processes on the effectiveness of plant molecular pharming systems.

  19. Characterization of proinsulin- and proglucagon-converting activities in isolated islet secretory granules.

    PubMed

    Fletcher, D J; Quigley, J P; Bauer, G E; Noe, B D

    1981-08-01

    The conversion of proglucagon and proinsulin by secretory granules isolated from both prelabeled and unlabeled anglerfish islets was investigated. Either granules isolated from tissue labeled with [3H]tryptophan and [14C]isoleucine or [35S]cysteine, or lysed granules from unlabeled tissue to which exogenously labeled prohormones had been added were incubated under various conditions. Acetic acid extracts of these granule preparations were analyzed for prohormone and hormone content by gel filtration. Both prelabeled and lysed, unlabeled secretory granules converted radiolabeled precursor peptides (Mr 8,000-15,000) to labeled insulin and glucagon. The accuracy of the cleavage process was established by demonstrating comigration of products obtained from in vitro cleavage with insulin and glucagon extracted from intact islets using electrophoresis and high-pressure liquid chromatography (HPLC). The pH optimum for granule-mediated conversion was found to be in the range of pH 4.5-5.5. Conversion of both proglucagon and proinsulin by secretory granules was significantly inhibited in the presence of antipain, leupeptin, p-chloromercuribenzoate (PCMB) or dithiodipyridine (DDP) but not chloroquine, diisopropyl fluorophosphate, EDTA, p-nitrophenyl guanidinobenzoate, soybean trypsin inhibitor, or N-p-tosyl-L-lysine chloromethyl ketone HCl. The inhibitory action of PCMB and DDP was reversed in the presence of dithiothreitol. Both membranous and soluble components of the secretory granules possessed significant converting activity. HPLC and electrophoretic analysis of cleavage products demonstrated that the converting activities of the membranous and soluble components were indistinguishable. The amount of inhibition of proinsulin and proglucagon conversion caused by 600 micrograms/ml porcine proinsulin was significantly lower than that caused by the same concentration of unlabeled anglerfish precursor peptides. These results indicate that the proinsulin and proglucagon

  20. [Enzymatic activity and therapeutic action of pepsin K in chronic gastritis with secretory failure].

    PubMed

    Kharitonin, V V; Chernenko, G T; Sdobnova, E A; Khliabich, A G

    2003-01-01

    Pepsin K (chicken pepsin) in the test for hemoglobin proteolysis is 1.7 times superior to abomin (porcine pepsin) in the medium pH 2 and 44 times more potent in the medium pH 3. Even in pH 4 chicken pepsin retains its enzymatic activity while porcine pepsin in pH 4 looses its activity. These biochemical findings show that pepsin K is more effective in the treatment of enzymatic insufficiency of the stomach. Intake of 1-3 pepsin K tablets after meal for 4 weeks by 82 patients having chronic gastritis with secretory insufficiency was effective in 75% of patients.

  1. Association of IgA secretory component sialylation with leucocytospermia of infertile men - a pilot study.

    PubMed

    Kratz, E M; Ferens-Sieczkowska, M

    2014-12-01

    The aim of our pilot study was to check whether the differences in IgA secretory component (SC) sialylation are associated with leucocytospermia. In normozoospermic and leucocytospermic seminal plasmas, 78-kDa and 63-kDa SC immunoreactive bands were observed. The SC sialylation was analysed by lectin blotting, using sialo-specific lectins MAA (Maackia amurensis agglutinin) and SNA (Sambucus nigra agglutinin). Specific reactivity of 63-kDa SC with MAA and SNA was higher than 78-kDa SC in both analysed seminal groups. The analysis of seminal SC sialylation might be a valuable diagnosis tools for the evaluation of fertility problems related with leucocytospermia.

  2. Transport and quality control of MHC class I molecules in the early secretory pathway.

    PubMed

    Springer, Sebastian

    2015-06-01

    Folding and peptide binding of major histocompatibility complex (MHC) class I molecules have been thoroughly researched, but the mechanistic connection between these biochemical events and the progress of class I through the early secretory pathway is much less well understood. This review focuses on the question how the partially assembled forms of class I (which lack high-affinity peptide and/or the light chain beta-2 microglobulin) are retained inside the cell. Such investigations offer researchers exciting chances to understand the connections between class I structure, conformational dynamics, peptide binding kinetics and thermodynamics, intracellular transport, and antigen presentation.

  3. In vitro production of Toxocara canis excretory-secretory (TES) antigen.

    PubMed

    Thomas, Divyamol; Jeyathilakan, N; Abdul Basith, S; Senthilkumar, T M A

    2016-09-01

    Toxocara canis is a widespread gastrointestinal nematode parasite of dogs and cause Toxocara larva migrans, an important zoonotic disease in humans on ingestion of infective eggs. Toxocarosis is one of the few human parasitic diseases whose serodiagnosis uses a standardized antigen, T. canis excretory secretory antigen (TES). The present study describes collection of T. canis adult worm, collection and embryonation of T. canis eggs, hatching and separation of T. canis larvae, in vitro maintenance of T. canis second stage larvae for production of TES, concentration of culture fluid TES and yield of TES in correlation with various methods cited in literature. PMID:27605834

  4. [Analysis of the effect of diabetes type 2 duration on beta cell secretory function and insulin resistance].

    PubMed

    Popović, Ljiljana; Zamaklar, Miroslava; Lalić, Katarina; Vasović, Olga

    2006-01-01

    Diabetes type 2 is a chronic metabolic disorder. Pathogenesis of diabetes type 2 results from the impaired insulin secretion, impaired insulin action and increased endogenous glucose production. Diabetes evolves through several phases characterized by qualitative and quantitative changes of beta cell secretory function. The aim of our study was to analyze the impact of diabetes duration on beta cell secretory function and insulin resistance. The results indicated significant negative correlation of diabetes duration and fasting insulinemia, as well as beta cell secretory function assessed by HOMA beta index. Our study also found significant negative correlation of diabetes duration and insulin resistance assessed by HOMA IR index. Significant positive correlation was established between beta cell secretory capacity (fasting insulinemia and HOMA beta) and insulin resistance assessed by HOMA IR index, independently of diabetes duration. These results indicate that: beta cell secretory capacity, assessed by HOMA beta index, significantly decreases with diabetes duration. In parallel with decrease of fasting insulinemia, reduction of insulin resistance assessed by HOMA IR index was found as well.

  5. Abnormal ion content, hydration and granule expansion of the secretory granules from cystic fibrosis airway glandular cells

    SciTech Connect

    Baconnais, S.; Delavoie, F. |; Zahm, J.M.; Milliot, M.; Castillon, N.; Terryn, C.; Banchet, V.; Michel, J.; Danos, O.; Merten, M.; Chinet, T.; Zierold, K.; Bonnet, N.; Puchelle, E. , E-Mail: edith.puchelle@univ-reims.fr; Balossier, G.

    2005-10-01

    The absence or decreased expression of cystic fibrosis transmembrane conductance regulator (CFTR) induces increased Na{sup +} absorption and hyperabsorption of the airway surface liquid (ASL) resulting in a dehydrated and hyperviscous ASL. Although the implication of abnormal airway submucosal gland function has been suggested, the ion and water content in the Cystic Fibrosis (CF) glandular secretory granules, before exocytosis, is unknown. We analyzed, in non-CF and CF human airway glandular cell lines (MM-39 and KM4, respectively), the ion content in the secretory granules by electron probe X-ray microanalysis and the water content by quantitative dark field imaging on freeze-dried cryosections. We demonstrated that the ion content (Na{sup +}, Mg{sup 2+}, P, S and Cl{sup -}) is significantly higher and the water content significantly lower in secretory granules from the CF cell line compared to the non-CF cell line. Using videomicroscopy, we observed that the secretory granule expansion was deficient in CF glandular cells. Transfection of CF cells with CFTR cDNA or inhibition of non-CF cells with CFTR{sub inh}-172, respectively restored or decreased the water content and granule expansion, in parallel with changes in ion content. We hypothesize that the decreased water and increased ion content in glandular secretory granules may contribute to the dehydration and increased viscosity of the ASL in CF.

  6. Genetic Evidence for the Role of the Vacuole in Supplying Secretory Organelles with Ca2+ in Hansenula polymorpha

    PubMed Central

    Fokina, Anastasia V.; Chechenova, Maria B.; Karginov, Azamat V.; Ter-Avanesyan, Michael D.; Agaphonov, Michael O.

    2015-01-01

    Processes taking place in the secretory organelles require Ca2+ and Mn2+, which in yeast are supplied by the Pmr1 ion pump. Here we observed that in the yeast Hansenula polymorpha Ca2+ deficiency in the secretory pathway caused by Pmr1 inactivation is exacerbated by (i) the ret1-27 mutation affecting COPI-mediated vesicular transport, (ii) inactivation of the vacuolar Ca2+ ATPase Pmc1 and (iii) inactivation of Vps35, which is a component of the retromer complex responsible for protein transport between the vacuole and secretory organelles. The ret1-27 mutation also exerted phenotypes indicating alterations in transport between the vacuole and secretory organelles. These data indicate that ret1-27, pmc1 and vps35 affect a previously unknown Pmr1-independent route of the Ca2+ delivery to the secretory pathway. We also observed that the vacuolar protein carboxypeptidase Y receives additional modifications of its glycoside chains if it escapes the Vps10-dependent sorting to the vacuole. PMID:26717478

  7. The murine IgM secretory poly(A) site contains dual upstream and downstream elements which affect polyadenylation.

    PubMed Central

    Phillips, C; Virtanen, A

    1997-01-01

    Regulation of polyadenylation efficiency at the secretory poly(A) site plays an essential role in gene expression at the immunoglobulin (IgM) locus. At this poly(A) site the consensus AAUAAA hexanucleotide sequence is embedded in an extended AU-rich region and there are two downstream GU-rich regions which are suboptimally placed. As these sequences are involved in formation of the polyadenylation pre-initiation complex, we examined their function in vivo and in vitro . We show that the upstream AU-rich region can function in the absence of the consensus hexanucleotide sequence both in vivo and in vitro and that both GU-rich regions are necessary for full polyadenylation activity in vivo and for formation of polyadenylation-specific complexes in vitro . Sequence comparisons reveal that: (i) the dual structure is distinct for the IgM secretory poly(A) site compared with other immunoglobulin isotype secretory poly(A) sites; (ii) the presence of an AU-rich region close to the consensus hexanucleotide is evolutionarily conserved for IgM secretory poly(A) sites. We propose that the dual structure of the IgM secretory poly(A) site provides a flexibility to accommodate changes in polyadenylation complex components during regulation of polyadenylation efficiency. PMID:9171084

  8. The challenge of improved secretory production of active pharmaceutical ingredients in Saccharomyces cerevisiae: a case study on human insulin analogs.

    PubMed

    Kazemi Seresht, Ali; Palmqvist, Eva A; Schluckebier, Gerd; Pettersson, Ingrid; Olsson, Lisbeth

    2013-10-01

    The yeast Saccharomyces cerevisiae has widely been used as a host for the production of heterologous proteins. Great attention has been put on improved secretory production of active pharmaceutical ingredients, and the secretory pathway of this eukaryotic host has been the playground of diverse strain engineering studies, aiming at enhanced cellular capacities for folding and trafficking of the target proteins. However, the cellular quality assessment for secretory proteins remains mostly unpredictable, and different target proteins often do not picture similar secretion yields, underlining the dependency of efficient secretion on the physicochemical properties of the protein of interest. In this study, two human insulin analog precursors (IAPs) with minor differences in their amino acid sequences were used as model secretory proteins. No differences between cells expressing these two proteins were found in the IAP transcript levels, gene copy numbers, or intra-cellularly accumulated proteins, yet a more than sevenfold difference in their secretion yields was found. Physiological characterization of cells expressing these proteins in batch processes revealed no significant difference in their specific growth rate, but an altered overflow metabolism. Global transcriptome analysis carried out in chemostat experiments pinpointed distinct steps during the protein maturation pathway to be differentially regulated and indicated an increased degradation of the IAP with the low secretion yield. In silico protein structure modeling of the IAPs suggested a difference in conformational stability, induced by the amino acid substitution, which most likely resulted in disparity in trafficking through the secretory pathway and thus a large difference in secretion yields. PMID:23592021

  9. Kinesin-related Smy1 enhances the Rab-dependent association of myosin-V with secretory cargo

    PubMed Central

    Lwin, Kyaw Myo; Li, Donghao; Bretscher, Anthony

    2016-01-01

    The mechanisms by which molecular motors associate with specific cargo is a central problem in cell organization. The kinesin-like protein Smy1 of budding yeast was originally identified by the ability of elevated levels to suppress a conditional myosin-V mutation (myo2-66), but its function with Myo2 remained mysterious. Subsequently, Myo2 was found to provide an essential role in delivery of secretory vesicles for polarized growth and in the transport of mitochondria for segregation. By isolating and characterizing myo2 smy1 conditional mutants, we uncover the molecular function of Smy1 as a factor that enhances the association of Myo2 with its receptor, the Rab Sec4, on secretory vesicles. The tail of Smy1—which binds Myo2—its central dimerization domain, and its kinesin-like head domain are all necessary for this function. Consistent with this model, overexpression of full-length Smy1 enhances the number of Sec4 receptors and Myo2 motors per transporting secretory vesicle. Rab proteins Sec4 and Ypt11, receptors for essential transport of secretory vesicles and mitochondria, respectively, bind the same region on Myo2, yet Smy1 functions selectively in the transport of secretory vesicles. Thus a kinesin-related protein can function intimately with a myosin-V and its receptor in the transport of a specific cargo. PMID:27307583

  10. Overproduction of a Model Sec- and Tat-Dependent Secretory Protein Elicits Different Cellular Responses in Streptomyces lividans.

    PubMed

    Gullón, Sonia; Marín, Silvia; Mellado, Rafael P

    2015-01-01

    Streptomyces lividans is considered an efficient host for the secretory production of homologous and heterologous proteins. To identify possible bottlenecks in the protein production process, a comparative transcriptomic approach was adopted to study cellular responses during the overproduction of a Sec-dependent model protein (alpha-amylase) and a Tat-dependent model protein (agarase) in Streptomyces lividans. The overproduction of the model secretory proteins via the Sec or the Tat route in S. lividans does elicit a different major cell response in the bacterium. The stringent response is a bacterial response to nutrients' depletion, which naturally occurs at late times of the bacterial cell growth. While the induction of the stringent response at the exponential phase of growth may limit overall productivity in the case of the Tat route, the induction of that response does not take place in the case of the Sec route, which comparatively is an advantage in secretory protein production processes. Hence, this study identifies a potential major drawback in the secretory protein production process depending on the secretory route, and provides clues to improving S. lividans as a protein production host.

  11. Genetic Evidence for the Role of the Vacuole in Supplying Secretory Organelles with Ca2+ in Hansenula polymorpha.

    PubMed

    Fokina, Anastasia V; Chechenova, Maria B; Karginov, Azamat V; Ter-Avanesyan, Michael D; Agaphonov, Michael O

    2015-01-01

    Processes taking place in the secretory organelles require Ca2+ and Mn2+, which in yeast are supplied by the Pmr1 ion pump. Here we observed that in the yeast Hansenula polymorpha Ca2+ deficiency in the secretory pathway caused by Pmr1 inactivation is exacerbated by (i) the ret1-27 mutation affecting COPI-mediated vesicular transport, (ii) inactivation of the vacuolar Ca2+ ATPase Pmc1 and (iii) inactivation of Vps35, which is a component of the retromer complex responsible for protein transport between the vacuole and secretory organelles. The ret1-27 mutation also exerted phenotypes indicating alterations in transport between the vacuole and secretory organelles. These data indicate that ret1-27, pmc1 and vps35 affect a previously unknown Pmr1-independent route of the Ca2+ delivery to the secretory pathway. We also observed that the vacuolar protein carboxypeptidase Y receives additional modifications of its glycoside chains if it escapes the Vps10-dependent sorting to the vacuole.

  12. Secretory breast carcinomas with ETV6-NTRK3 fusion gene belong to the basal-like carcinoma spectrum.

    PubMed

    Laé, Marick; Fréneaux, Paul; Sastre-Garau, Xavier; Chouchane, Olfa; Sigal-Zafrani, Brigitte; Vincent-Salomon, Anne

    2009-02-01

    Secretory breast carcinomas (<0.15% of breast tumors) are associated with a characteristic morphology and a favorable prognosis. Remarkably, this entity is the only epithelial tumor of the breast with a balanced translocation, t(12;15), that creates an ETV6-NTRK3 gene fusion encoding chimeric tyrosine kinase also encountered in cellular mesoblastic nephroma and infantile fibrosarcoma. The aim of this study was to determine the phenotypic class (ie luminal A/B, ERBB2, basal-like) of secretory breast carcinoma. A series of six secretory breast carcinomas were identified in our files. The ETV6 rearrangement was confirmed in all cases by fluorescence in situ hybridization. Immunophenotype was assessed with anti-ER, PR, ERBB2, KIT, EGFR, E-cadherin, vimentin, PS100, smooth muscle actin, basal (CK5/6 and 14), luminal cytokeratins (CK8/18) and p63 antibodies. In situ and invasive components shared the same immunoprofile and were ER, PR, ERBB2 negative with expression of basal cytokeratins. ETV6 gene alterations were present in both in situ and invasive components, highlighting their genetic similarities. The immunoprofile data (triple-negative with expression of basal markers) showed that secretory breast carcinomas with ETV6-NTRK3 fusion gene belong to the phenotypic basal-like spectrum of breast carcinomas. These results support the hypothesis that secretory breast carcinomas have immunohistochemical and genetic features that distinguish them from other basal-like tumors of the breast.

  13. Role of membrane oxidation in controlling the activity of human group IIa secretory phospholipase A(2) toward apoptotic lymphoma cells.

    PubMed

    Gibbons, Elizabeth; Nelson, Jennifer; Anderson, Lynn; Brewer, Kelly; Melchor, Stephanie; Judd, Allan M; Bell, John D

    2013-02-01

    The membranes of healthy lymphocytes normally resist hydrolysis by secretory phospholipase A(2). However, they become susceptible during the process of apoptosis. Previous experiments have demonstrated the importance of certain physical changes to the membrane during cell death such as a reduction in membrane lipid order and exposure of phosphatidylserine on the membrane surface. Nevertheless, those investigations also showed that at least one additional factor was required for rapid hydrolysis by the human group IIa phospholipase isozyme. This study was designed to test the possibility that oxidation of membrane lipids is the additional factor. Flow cytometry and confocal microscopy with a fluorescent probe of oxidative potential suggested that oxidation of the plasma membrane occurs during apoptosis stimulated by thapsigargin. When oxidative potential was high, the activity of human group IIa secretory phospholipase A(2) was enhanced 30- to 100-fold compared to that observed with conditions sufficient for maximal hydrolysis by other secretory phospholipase A(2) isoforms. Direct oxidation of cell membranes with either of two oxidizing agents also stimulated hydrolysis by secretory phospholipase A(2). Both oxidizers caused externalization of phosphatidylserine, but a change in lipid order did not always occur. These results demonstrated that membrane oxidation strongly stimulates human group IIa secretory phospholipase A(2) activity toward apoptotic cells. Interestingly, the change in membrane order, previously thought to be imperative for high rates of hydrolysis, was not required when membrane lipids were oxidized. Whether phosphatidylserine exposure is still necessary with oxidation remains unresolved since the two events could not be deconvoluted.

  14. Deletion of glutamate dehydrogenase in beta-cells abolishes part of the insulin secretory response not required for glucose homeostasis.

    PubMed

    Carobbio, Stefania; Frigerio, Francesca; Rubi, Blanca; Vetterli, Laurène; Bloksgaard, Maria; Gjinovci, Asllan; Pournourmohammadi, Shirin; Herrera, Pedro L; Reith, Walter; Mandrup, Susanne; Maechler, Pierre

    2009-01-01

    Insulin exocytosis is regulated in pancreatic ss-cells by a cascade of intracellular signals translating glucose levels into corresponding secretory responses. The mitochondrial enzyme glutamate dehydrogenase (GDH) is regarded as a major player in this process, although its abrogation has not been tested yet in animal models. Here, we generated transgenic mice, named betaGlud1(-/-), with ss-cell-specific GDH deletion. Our results show that GDH plays an essential role in the full development of the insulin secretory response. In situ pancreatic perfusion revealed that glucose-stimulated insulin secretion was reduced by 37% in betaGlud1(-/-). Furthermore, isolated islets with either constitutive or acute adenovirus-mediated knock-out of GDH showed a 49 and 38% reduction in glucose-induced insulin release, respectively. Adenovirus-mediated re-expression of GDH in betaGlud1(-/-) islets fully restored glucose-induced insulin release. Thus, GDH appears to account for about 40% of glucose-stimulated insulin secretion and to lack redundant mechanisms. In betaGlud1(-/-) mice, the reduced secretory capacity resulted in lower plasma insulin levels in response to both feeding and glucose load, while body weight gain was preserved. The results demonstrate that GDH is essential for the full development of the secretory response in beta-cells. However, maximal secretory capacity is not required for maintenance of glucose homeostasis in normo-caloric conditions.

  15. A novel imaging method for quantitative Golgi localization reveals differential intra-Golgi trafficking of secretory cargoes

    PubMed Central

    Tie, Hieng Chiong; Mahajan, Divyanshu; Chen, Bing; Cheng, Li; VanDongen, Antonius M. J.; Lu, Lei

    2016-01-01

    Cellular functions of the Golgi are determined by the unique distribution of its resident proteins. Currently, electron microscopy is required for the localization of a Golgi protein at the sub-Golgi level. We developed a quantitative sub-Golgi localization method based on centers of fluorescence masses of nocodazole-induced Golgi ministacks under conventional optical microscopy. Our method is rapid, convenient, and quantitative, and it yields a practical localization resolution of ∼30 nm. The method was validated by the previous electron microscopy data. We quantitatively studied the intra-Golgi trafficking of synchronized secretory membrane cargoes and directly demonstrated the cisternal progression of cargoes from the cis- to the trans-Golgi. Our data suggest that the constitutive efflux of secretory cargoes could be restricted at the Golgi stack, and the entry of the trans-Golgi network in secretory pathway could be signal dependent. PMID:26764092

  16. Effect of low temperature cultivation on insulin secretory of human pancreatic islets.

    PubMed

    Nikolic, D M; Djordjevic, P B; Lackovic, V B; Stojiljkovic, V; Stanojevic, B

    2013-01-01

    The experiment compared the physiological function (insulin secretory capacity) and membrane integrity of human adult pancreatic islets incubated in culture at 37°C and 24°C. Pancreatic tissue was digested with Collagenase XI, using a non-automated method. Cultures were incubated at 37°C and 24°C. Secretory capacity of the islets is determined by measuring of the stimulation index (SI) on the 1st, 3rd and 7th day of cultivation. Membrane integrity of the islets was determined by dithizone staining. Both groups of examined cultures show a slight increase in SI during the incubation. However islets incubated at 24°C show higher SI values than those incubated at 37°C on the 1st, 3rd and 7th day of incubation. And on the first day of incubation, this difference was statistically significant (p <0.05). Islets incubated at 37°C showed preservation of membrane integrity, the islets are regular spherical shape, while those incubated at 24°C lose such an organization. During the seven-day cultivation, islets incubated at a standard temperature of 37°C show less preserve physiological functions in relation to cultures incubated at 24°C, but islets incubated at 37°C show more regular morphological forms. PMID:23489685

  17. SORCS1 is necessary for normal insulin secretory granule biogenesis in metabolically stressed β cells.

    PubMed

    Kebede, Melkam A; Oler, Angie T; Gregg, Trillian; Balloon, Allison J; Johnson, Adam; Mitok, Kelly; Rabaglia, Mary; Schueler, Kathryn; Stapleton, Donald; Thorstenson, Candice; Wrighton, Lindsay; Floyd, Brendan J; Richards, Oliver; Raines, Summer; Eliceiri, Kevin; Seidah, Nabil G; Rhodes, Christopher; Keller, Mark P; Coon, Joshua L; Audhya, Anjon; Attie, Alan D

    2014-10-01

    We previously positionally cloned Sorcs1 as a diabetes quantitative trait locus. Sorcs1 belongs to the Vacuolar protein sorting-10 (Vps10) gene family. In yeast, Vps10 transports enzymes from the trans-Golgi network (TGN) to the vacuole. Whole-body Sorcs1 KO mice, when made obese with the leptin(ob) mutation (ob/ob), developed diabetes. β Cells from these mice had a severe deficiency of secretory granules (SGs) and insulin. Interestingly, a single secretagogue challenge failed to consistently elicit an insulin secretory dysfunction. However, multiple challenges of the Sorcs1 KO ob/ob islets consistently revealed an insulin secretion defect. The luminal domain of SORCS1 (Lum-Sorcs1), when expressed in a β cell line, acted as a dominant-negative, leading to SG and insulin deficiency. Using syncollin-dsRed5TIMER adenovirus, we found that the loss of Sorcs1 function greatly impairs the rapid replenishment of SGs following secretagogue challenge. Chronic exposure of islets from lean Sorcs1 KO mice to high glucose and palmitate depleted insulin content and evoked an insulin secretion defect. Thus, in metabolically stressed mice, Sorcs1 is important for SG replenishment, and under chronic challenge by insulin secretagogues, loss of Sorcs1 leads to diabetes. Overexpression of full-length SORCS1 led to a 2-fold increase in SG content, suggesting that SORCS1 is sufficient to promote SG biogenesis. PMID:25157818

  18. Bacterial mimetics of endocrine secretory granules as immobilized in vivo depots for functional protein drugs

    PubMed Central

    Céspedes, María Virtudes; Fernández, Yolanda; Unzueta, Ugutz; Mendoza, Rosa; Seras-Franzoso, Joaquin; Sánchez-Chardi, Alejando; Álamo, Patricia; Toledo-Rubio, Verónica; Ferrer-Miralles, Neus; Vázquez, Esther; Schwartz, Simó; Abasolo, Ibane; Corchero, José Luis; Mangues, Ramon; Villaverde, Antonio

    2016-01-01

    In the human endocrine system many protein hormones including urotensin, glucagon, obestatin, bombesin and secretin, among others, are supplied from amyloidal secretory granules. These granules form part of the so called functional amyloids, which within the whole aggregome appear to be more abundant than formerly believed. Bacterial inclusion bodies (IBs) are non-toxic, nanostructured functional amyloids whose biological fabrication can be tailored to render materials with defined biophysical properties. Since under physiological conditions they steadily release their building block protein in a soluble and functional form, IBs are considered as mimetics of endocrine secretory granules. We have explored here if the in vivo implantation of functional IBs in a given tissue would represent a stable local source of functional protein. Upon intratumoral injection of bacterial IBs formed by a potent protein ligand of CXCR4 we have observed high stability and prevalence of the material in absence of toxicity, accompanied by apoptosis of CXCR4+ cells and tumor ablation. Then, the local immobilization of bacterial amyloids formed by therapeutic proteins in tumors or other tissues might represent a promising strategy for a sustained local delivery of protein drugs by mimicking the functional amyloidal architecture of the mammals’ endocrine system. PMID:27775083

  19. PLURIVESICULAR SECRETORY PROCESSES AND NERVE ENDINGS IN THE PINEAL GLAND OF THE RAT

    PubMed Central

    De Robertis, Eduardo; de Iraldi, Amanda Pellegrino

    1961-01-01

    The pineal body of white normal rats, 1.5 to 3 months old, was studied under the electron microscope. A single type of parenchymal cell—the pinealocyte—is recognized as the main component of the tissue, and some of the structural characteristics of the nucleus and cytoplasm are described. The main morphological characteristic of the pinealocytes is represented by club-shaped perivascular expansions connected to the cell by thin pedicles. They are found lying in a large, clear space surrounding the blood capillaries. The name plurivesicular secretory processes is proposed, to emphasize the main structural feature and the probable function of these cellular expansions. A tubulofibrillar component is mainly found in the pedicle, and within the expansion there are numerous small mitochondria and densily packed vesicles of about 425 A. Two types of vesicles, one with a homogeneous content and another with a very dense osmium deposit, are described. Between the two types there are intermediary forms. In these processes, mitochondria show profound changes which may lead to complete vacuolization. The significance of this plurivesicular secretory component is discussed in the light of recent work on the biogenic amines of the pineal body and preliminary experiments showing the release of the vesicles containing dense granules after treatment with reserpine. These vesicles are interpreted as the site of storage of some of the biogenic amines. Bundles of unmyelinated nerve fibers and endings on large blood vessels which also contain a plurivesicular content are described and tentatively interpreted as adrenergic nerve terminals. PMID:13720811

  20. Non Secretory Multiple Myeloma With Extensive Extramedullary Plasmacytoma: A Diagnostic Dilemma

    PubMed Central

    Low, Soo Fin; Mohd Tap, Nor Hanani; Kew, Thean Yean; Ngiu, Chai Soon; Sridharan, Radhika

    2015-01-01

    Multiple myeloma (MM) is characterized by progressive proliferation of malignant plasma cells, usually initiating in the bone marrow. MM can affect any organ; a total of 7 - 18% of patients with MM demonstrate extramedullary involvement at diagnosis. Non-secretory multiple myeloma (NSMM) is a rare variant that accounts for 1 - 5% of all cases of multiple myeloma. The disease is characterized by the absence of monoclonal gammopathy in serum and urine electrophoresis. Our case report highlights the diagnostic challenge of a case of NSMM with extensive extramedullary involvement in a young female patient who initially presented with right shoulder pain and bilateral breasts lumps. Skeletal survey showed multiple lytic bony lesions. The initial diagnosis was primary breast carcinoma with osseous metastases. No monoclonal gammopathy was found in the serum or urine electrophoresis. Bone marrow and breast biopsies revealed marked plasmacytosis. The diagnosis was delayed for a month in view of the lack of clinical suspicion of multiple myeloma in a young patient and scant biochemical expression of non-secretory type of multiple myeloma. PMID:26528383

  1. Identification and Functional Characterization of Leishmania donovani Secretory Peroxidase: Delineating Its Role in NRAMP1 Regulation

    PubMed Central

    Singh, Rakesh K.

    2013-01-01

    Leishmania silently evades host immune system and establish in the hostile environment of host macrophage phagolysosomes. For differentiation, growth and division parasite acquires divalent cations especially iron from the host nutritive pool. Natural resistance associated with macrophage protein1 (NRAMP1), a cation transporter that effluxes out divalent cations specifically iron from phagosomal milieu to the cytosol, to create ions deprived status for pathogenic microorganisms. The mechanisms of NRAMP1 regulation are largely unknown in leishmanial infections. In the present study, we identified a secretory Leishmania donovani peroxidase (Prx) that showed peroxidoxin like peroxidase activity and significantly reduced H2O2, O2.− and NO levels in LPS activated macrophages. Further, we also observed down regulated Nramp1 expression and concomitantly declined labile iron pool in activated macrophages treated with identified peroxidase. Prx also decreased levels of TNF-α, IFN-γ and IL-12 in LPS activated macrophages. These observations indicate a bifunctional protective role of secretory Prx; first it reduces redox activation of macrophages, and secondly it allows iron access to Leishmania by down regulating NRAMP1 expression. PMID:23326430

  2. Pancreatic β-Cell Adaptive Plasticity in Obesity Increases Insulin Production but Adversely Affects Secretory Function.

    PubMed

    Alarcon, Cristina; Boland, Brandon B; Uchizono, Yuji; Moore, Patrick C; Peterson, Bryan; Rajan, Suryalekha; Rhodes, Olivia S; Noske, Andrew B; Haataja, Leena; Arvan, Peter; Marsh, Bradly J; Austin, Jotham; Rhodes, Christopher J

    2016-02-01

    Pancreatic β-cells normally produce adequate insulin to control glucose homeostasis, but in obesity-related diabetes, there is a presumed deficit in insulin production and secretory capacity. In this study, insulin production was assessed directly in obese diabetic mouse models, and proinsulin biosynthesis was found to be contrastingly increased, coupled with a significant expansion of the rough endoplasmic reticulum (without endoplasmic reticulum stress) and Golgi apparatus, increased vesicular trafficking, and a depletion of mature β-granules. As such, β-cells have a remarkable capacity to produce substantial quantities of insulin in obesity, which are then made available for immediate secretion to meet increased metabolic demand, but this comes at the price of insulin secretory dysfunction. Notwithstanding, it can be restored. Upon exposing isolated pancreatic islets of obese mice to normal glucose concentrations, β-cells revert back to their typical morphology with restoration of regulated insulin secretion. These data demonstrate an unrealized dynamic adaptive plasticity of pancreatic β-cells and underscore the rationale for transient β-cell rest as a treatment strategy for obesity-linked diabetes. PMID:26307586

  3. Myosin Va Transports Dense Core Secretory Vesicles in Pancreatic MIN6 β-CellsV⃞

    PubMed Central

    Varadi, Aniko; Tsuboi, Takashi; Rutter, Guy A.

    2005-01-01

    The role of unconventional myosins in neuroendocrine cells is not fully understood, with involvement suggested in the movement of both secretory vesicles and mitochondria. Here, we demonstrate colocalization of myosin Va (MyoVa) with insulin in pancreatic β-cells and show that MyoVa copurifies with insulin in density gradients and with the vesicle marker phogrin-enhanced green fluorescent protein upon fluorescence-activated sorting of vesicles. By contrast, MyoVa immunoreactivity was poorly colocalized with mitochondrial or other markers. Demonstrating an important role for MyoVa in the recruitment of secretory vesicles to the cell surface, a reduction of MyoVa protein levels achieved by RNA interference caused a significant decrease in glucose- or depolarization-stimulated insulin secretion. Similarly, expression of the dominant-negative–acting globular tail domain of MyoVa decreased by ∼50% the number of vesicles docked at the plasma membrane and by 87% the number of depolarization-stimulated exocytotic events detected by total internal reflection fluorescence microscopy. We conclude that MyoVa-driven movements of vesicles along the cortical actin network are essential for the terminal stages of regulated exocytosis in β-cells. PMID:15788565

  4. Vitamin A deficiency and small intestinal secretory function in the rat.

    PubMed Central

    Nzegwu, H; Levin, R J

    1991-01-01

    The influence of vitamin A on the functions of the small intestine was examined in rats made vitamin A deficient for 40 days by feeding a special diet after weaning and in pair fed vitamin A deficient rats that were given supplementary vitamin A (240 IU/day) in their drinking water. The basal and stimulated electrogenic secretory and absorptive functions of the jejunum and proximal and distal ileum removed from these rats were examined in vitro using the short circuit current as the index of transport activity. The basal short circuit current in the jejunum and proximal ileum was not significantly different but that of the distal ileum was lower. Electrogenic glucose transfer was not significantly affected by the vitamin deficiency. Cholinergic stimulation using the M1/M2 agonist bethanechol showed a greatly enhanced electrogenic secretion in the jejunum of the deficient rats while secretion stimulated by dibutyryl cyclic adenosine monophosphate was significantly greater in their distal ilea compared with the supplemented group. The vitamin deficiency also disrupted the normal higher/lower hierarchical pattern of transport activity between the proximal and distal ileum. The enhanced secretory activity of the vitamin A deficient small intestine offers a putative explanation for the well known relation between vitamin A deficiency and diarrhoea found in humans. PMID:1721598

  5. Identification of Secretory Proteins in Mycobacterium tuberculosis Using Pseudo Amino Acid Composition.

    PubMed

    Yang, Huan; Tang, Hua; Chen, Xin-Xin; Zhang, Chang-Jian; Zhu, Pan-Pan; Ding, Hui; Chen, Wei; Lin, Hao

    2016-01-01

    Tuberculosis is killing millions of lives every year and on the blacklist of the most appalling public health problems. Recent findings suggest that secretory protein of Mycobacterium tuberculosis may serve the purpose of developing specific vaccines and drugs due to their antigenicity. Responding to global infectious disease, we focused on the identification of secretory proteins in Mycobacterium tuberculosis. A novel method called MycoSec was designed by incorporating g-gap dipeptide compositions into pseudo amino acid composition. Analysis of variance-based technique was applied in the process of feature selection and a total of 374 optimal features were obtained and used for constructing the final predicting model. In the jackknife test, MycoSec yielded a good performance with the area under the receiver operating characteristic curve of 0.93, demonstrating that the proposed system is powerful and robust. For user's convenience, the web server MycoSec was established and an obliging manual on how to use it was provided for getting around any trouble unnecessary. PMID:27597968

  6. SORCS1 is necessary for normal insulin secretory granule biogenesis in metabolically stressed β cells

    PubMed Central

    Kebede, Melkam A.; Oler, Angie T.; Gregg, Trillian; Balloon, Allison J.; Johnson, Adam; Mitok, Kelly; Rabaglia, Mary; Schueler, Kathryn; Stapleton, Donald; Thorstenson, Candice; Wrighton, Lindsay; Floyd, Brendan J.; Richards, Oliver; Raines, Summer; Eliceiri, Kevin; Seidah, Nabil G.; Rhodes, Christopher; Keller, Mark P.; Coon, Joshua L.; Audhya, Anjon; Attie, Alan D.

    2014-01-01

    We previously positionally cloned Sorcs1 as a diabetes quantitative trait locus. Sorcs1 belongs to the Vacuolar protein sorting-10 (Vps10) gene family. In yeast, Vps10 transports enzymes from the trans-Golgi network (TGN) to the vacuole. Whole-body Sorcs1 KO mice, when made obese with the leptinob mutation (ob/ob), developed diabetes. β Cells from these mice had a severe deficiency of secretory granules (SGs) and insulin. Interestingly, a single secretagogue challenge failed to consistently elicit an insulin secretory dysfunction. However, multiple challenges of the Sorcs1 KO ob/ob islets consistently revealed an insulin secretion defect. The luminal domain of SORCS1 (Lum-Sorcs1), when expressed in a β cell line, acted as a dominant-negative, leading to SG and insulin deficiency. Using syncollin-dsRed5TIMER adenovirus, we found that the loss of Sorcs1 function greatly impairs the rapid replenishment of SGs following secretagogue challenge. Chronic exposure of islets from lean Sorcs1 KO mice to high glucose and palmitate depleted insulin content and evoked an insulin secretion defect. Thus, in metabolically stressed mice, Sorcs1 is important for SG replenishment, and under chronic challenge by insulin secretagogues, loss of Sorcs1 leads to diabetes. Overexpression of full-length SORCS1 led to a 2-fold increase in SG content, suggesting that SORCS1 is sufficient to promote SG biogenesis. PMID:25157818

  7. DHRSX, a novel non-classical secretory protein associated with starvation induced autophagy.

    PubMed

    Zhang, Guoying; Luo, Yang; Li, Ge; Wang, Lanlan; Na, Daxiang; Wu, Xiaotong; Zhang, Yingmei; Mo, Xiaoning; Wang, Lu

    2014-01-01

    Dehydrogenase/reductase (SDR family) X-linked (DHRSX) is a novel human gene without any substantial functional annotation and was initially cloned and identified in our laboratory. In this study, we present evidence that it encodes a non-classical secretory protein and promotes starvation induced autophagy. Using the Baf.A1 assay and N-terminal sequencing, we showed that DHRSX is secreted in a non-classical form. We expressed and purified a recombinant human GST-DHRSX fusion protein. Functional studies revealed that HeLa and U2OS cells overexpressing DHRSX or treated with the GST-DHRSX fusion protein exhibited higher levels of starvation-induced autophagy, resulting in increased endogenous LC3-II levels, a punctate GFP-LC3 distribution, and structures associated with autophagy, with a lower accumulation of autophagy substrates such as p62 and polyQ80. Accordingly, knockdown of endogenous DHRSX through specific siRNAs reduced LC3-II levels obviously in U2OS cells induced by starvation. Collectively, these results demonstrate that DHRSX is a novel non-classical secretory protein involved in the positive regulation of starvation induced autophagy and provide a new avenue for research on this protein family and autophagy regulation.

  8. Identification of Secretory Proteins in Mycobacterium tuberculosis Using Pseudo Amino Acid Composition

    PubMed Central

    Yang, Huan; Tang, Hua; Chen, Xin-Xin; Zhang, Chang-Jian; Zhu, Pan-Pan; Ding, Hui

    2016-01-01

    Tuberculosis is killing millions of lives every year and on the blacklist of the most appalling public health problems. Recent findings suggest that secretory protein of Mycobacterium tuberculosis may serve the purpose of developing specific vaccines and drugs due to their antigenicity. Responding to global infectious disease, we focused on the identification of secretory proteins in Mycobacterium tuberculosis. A novel method called MycoSec was designed by incorporating g-gap dipeptide compositions into pseudo amino acid composition. Analysis of variance-based technique was applied in the process of feature selection and a total of 374 optimal features were obtained and used for constructing the final predicting model. In the jackknife test, MycoSec yielded a good performance with the area under the receiver operating characteristic curve of 0.93, demonstrating that the proposed system is powerful and robust. For user's convenience, the web server MycoSec was established and an obliging manual on how to use it was provided for getting around any trouble unnecessary. PMID:27597968

  9. Identification of Secretory Proteins in Mycobacterium tuberculosis Using Pseudo Amino Acid Composition

    PubMed Central

    Yang, Huan; Tang, Hua; Chen, Xin-Xin; Zhang, Chang-Jian; Zhu, Pan-Pan; Ding, Hui

    2016-01-01

    Tuberculosis is killing millions of lives every year and on the blacklist of the most appalling public health problems. Recent findings suggest that secretory protein of Mycobacterium tuberculosis may serve the purpose of developing specific vaccines and drugs due to their antigenicity. Responding to global infectious disease, we focused on the identification of secretory proteins in Mycobacterium tuberculosis. A novel method called MycoSec was designed by incorporating g-gap dipeptide compositions into pseudo amino acid composition. Analysis of variance-based technique was applied in the process of feature selection and a total of 374 optimal features were obtained and used for constructing the final predicting model. In the jackknife test, MycoSec yielded a good performance with the area under the receiver operating characteristic curve of 0.93, demonstrating that the proposed system is powerful and robust. For user's convenience, the web server MycoSec was established and an obliging manual on how to use it was provided for getting around any trouble unnecessary.

  10. A fast method to study the secretory activity of neuroendocrine cells at the ultrastructural level.

    PubMed

    Van Herp, F; Coenen, T; Geurts, H P M; Janssen, G J A; Martens, G J M

    2005-04-01

    Cryo field emission scanning electron microscopy (cryo-FE-SEM) is a versatile technique that allows the investigation of the three-dimensional organization of cells at the ultrastructural level over a wide range of magnifications. Unfortunately, cryopreparation of the specimens for this technique remains cumbersome, in particular because ice crystal formation must be prevented during freezing. Here we report that a light prefixation with glutaraldehyde and incubation in glycerol as cryoprotectant or a high-pressure freezing approach are both excellent procedures for cryopreparation of animal cells to be used in combination with cryo-FE-SEM. Using the proopiomelanocortin-producing intermediate pituitary melanotrope cells of Xenopus laevis as a physiologically inducible neuroendocrine system, we compared the ultrastructural characteristics of inactive and hyperactive neuroendocrine cells. The overall quality of the ultrastructural images was comparable for the two cryopreparation procedures, although some fine structures were better conserved using high-pressure freezing. Melanotrope cells in a secretory inactive state contained numerous storage granules and a poorly developed endoplasmic reticulum (ER), while large amounts of rough ER were present in hyperactive cells. Thus, the cryo-FE-SEM approach described here allows a fast ultrastructural study on the secretory activity of neuroendocrine cells.

  11. Prospore membrane formation defines a developmentally regulated branch of the secretory pathway in yeast.

    PubMed

    Neiman, A M

    1998-01-12

    Spore formation in yeast is an unusual form of cell division in which the daughter cells are formed within the mother cell cytoplasm. This division requires the de novo synthesis of a membrane compartment, termed the prospore membrane, which engulfs the daughter nuclei. The effect of mutations in late-acting genes on sporulation was investigated. Mutation of SEC1, SEC4, or SEC8 blocked spore formation, and electron microscopic analysis of the sec4-8 mutant indicated that this inability to produce spores was caused by a failure to form the prospore membrane. The soluble NSF attachment protein 25 (SNAP-25) homologue SEC9, by contrast, was not required for sporulation. The absence of a requirement for SEC9 was shown to be due to the sporulation-specific induction of a second, previously undescribed, SNAP-25 homologue, termed SPO20. These results define a developmentally regulated branch of the secretory pathway and suggest that spore morphogenesis in yeast proceeds by the targeting and fusion of secretory vesicles to form new plasma membranes in the interior of the mother cell. Consistent with this model, the extracellular proteins Gas1p and Cts1p were localized to an internal compartment in sporulating cells. Spore formation in yeast may be a useful model for understanding secretion-driven cell division events in a variety of plant and animal systems.

  12. Immunodominant antigens in Naegleria fowleri excretory--secretory proteins were potential pathogenic factors.

    PubMed

    Kim, Jong-Hyun; Yang, Ae-Hee; Sohn, Hae-Jin; Kim, Daesik; Song, Kyoung-Ju; Shin, Ho-Joon

    2009-11-01

    Naegleria fowleri, a ubiquitous pathogenic free-living amoeba, is the most virulent species and causes primary amoebic meningoencephalitis in laboratory animals and humans. The parasite secretes various inducing molecules as biological responses, which are thought to be involved in pathophysiological and immunological events during infection. To investigate what molecules of N. fowleri excretory-secretory proteins (ESPs) are related with amoebic pathogenicity, N. fowleri ESPs fractionated by two-dimensional electrophoresis were reacted with N. fowleri infection or immune sera. To identify immunodominant ESPs, six major protein spots were selected and analyzed by N-terminal sequencing. Finally, six proteins, 58, 40, 24, 21, 18, and 16 kDa of molecular weight, were partially cloned and matched with reference proteins as follow: 58 kDa of exendin-3 precursor, 40 kDa of secretory lipase, 24 kDa of cathepsin B-like proteases and cysteine protease, 21 kDa of cathepsin B, 18 kDa of peroxiredoxin, and 16 kDa of thrombin receptor, respectively. These results suggest that N. fowleri ESPs contained important proteins, which may play an important role in the pathogenicity of N. fowleri.

  13. Exocytosis of Alphaherpesvirus Virions, Light Particles, and Glycoproteins Uses Constitutive Secretory Mechanisms

    PubMed Central

    Hogue, Ian B.; Scherer, Julian

    2016-01-01

    ABSTRACT Many molecular and cell biological details of the alphaherpesvirus assembly and egress pathway remain unclear. Recently we developed a live-cell fluorescence microscopy assay of pseudorabies virus (PRV) exocytosis, based on total internal reflection fluorescence (TIRF) microscopy and a virus-encoded pH-sensitive fluorescent probe. Here, we use this assay to distinguish three classes of viral exocytosis in a nonpolarized cell type: (i) trafficking of viral glycoproteins to the plasma membrane, (ii) exocytosis of viral light particles, and (iii) exocytosis of virions. We find that viral glycoproteins traffic to the cell surface in association with constitutive secretory Rab GTPases and exhibit free diffusion into the plasma membrane after exocytosis. Similarly, both virions and light particles use these same constitutive secretory mechanisms for egress from infected cells. Furthermore, we show that viral light particles are distinct from cellular exosomes. Together, these observations shed light on viral glycoprotein trafficking steps that precede virus particle assembly and reinforce the idea that virions and light particles share a biogenesis and trafficking pathway. PMID:27273828

  14. Amyloid formation of growth hormone in presence of zinc: Relevance to its storage in secretory granules

    PubMed Central

    Jacob, Reeba S.; Das, Subhadeep; Ghosh, Saikat; Anoop, Arunagiri; Jha, Narendra Nath; Khan, Tuhin; Singru, Praful; Kumar, Ashutosh; Maji, Samir K.

    2016-01-01

    Amyloids are cross-β-sheet fibrillar aggregates, associated with various human diseases and native functions such as protein/peptide hormone storage inside secretory granules of neuroendocrine cells. In the current study, using amyloid detecting agents, we show that growth hormone (GH) could be stored as amyloid in the pituitary of rat. Moreover, to demonstrate the formation of GH amyloid in vitro, we studied various conditions (solvents, glycosaminoglycans, salts and metal ions) and found that in presence of zinc metal ions (Zn(II)), GH formed short curvy fibrils. The amyloidogenic nature of these fibrils was examined by Thioflavin T binding, Congo Red binding, transmission electron microscopy and X-ray diffraction. Our biophysical studies also suggest that Zn(II) initiates the early oligomerization of GH that eventually facilitates the fibrillation process. Furthermore, using immunofluorescence study of pituitary tissue, we show that GH in pituitary significantly co-localizes with Zn(II), suggesting the probable role of zinc in GH aggregation within secretory granules. We also found that GH amyloid formed in vitro is capable of releasing monomers. The study will help to understand the possible mechanism of GH storage, its regulation and monomer release from the somatotrophs of anterior pituitary. PMID:27004850

  15. Aquaporin 1 regulates GTP-induced rapid gating of water in secretory vesicles.

    PubMed

    Cho, Sang-Joon; Sattar, A K M Abdus; Jeong, Eun-Hwan; Satchi, Mylan; Cho, Jin Ah; Dash, Sudhansu; Mayes, Mary Sue; Stromer, Marvin H; Jena, Bhanu P

    2002-04-01

    The swelling of secretory vesicles has been implicated in exocytosis, but the underlying mechanism of vesicle swelling remains largely unknown. Zymogen granules (ZGs), the membrane-bound secretory vesicles in exocrine pancreas, swell in response to GTP mediated by a G(alpha)i3 protein. Evidence is presented here that the water channel aquaporin-1 (AQP1) is present in the ZG membrane and participates in rapid GTP-induced vesicular water gating and swelling. Isolated ZGs exhibit low basal water permeability. However, exposure of granules to GTP results in a marked potentiation of water entry. Treatment of ZGs with the known water channel inhibitor Hg2+ is accompanied by a reversible loss in both the basal and GTP-stimulatable water entry and vesicle swelling. Introduction of AQP1-specific antibody raised against the carboxyl-terminal domain of AQP1 blocks GTP-stimulable swelling of vesicles. Our results demonstrate that AQP1 associated at the ZG membrane is involved in basal as well as GTP-induced rapid gating of water in ZGs of the exocrine pancreas.

  16. Over-production of various secretory-form proteins in Streptomyces lividans.

    PubMed

    Noda, Shuhei; Ito, Yuko; Shimizu, Nobuaki; Tanaka, Tsutomu; Ogino, Chiaki; Kondo, Akihiko

    2010-10-01

    Streptomyces lividans is known to produce large amounts of proteins in culture supernatants. In this report, to expand the secretory expression system with a strong promoter derived from phospholipase D of Streptoverticillium cinnamoneum, we expressed three kinds of proteins: transglutaminase from Stv. cinnamoneum (StvcMTG) and beta-1,4-endoglucanase and beta-glucosidase from Thermobifida fusca YX. The StvcMTG gene was introduced into S. lividans using the shuttle vector pUC702 for Escherichia coli and S. lividans, and high level secretory production of StvcMTG (230 microg/ml in the culture supernatant) was achieved. The other prokaryotic proteins, beta-1,4-endoglucanase and beta-glucosidase, were also expressed in (His)(6)-tag fused form into culture supernatants and retained high activity. Furthermore, complete purification was achieved by conventional column or affinity column chromatography for each recombinant protein with 1 mg/ml over protein concentration. Three independent proteins were thus successfully expressed and purified, and we expect to use this system for the expression of other valuable heterologous proteins.

  17. Ionic and secretory response of pancreatic islet cells to minoxidil sulfate

    SciTech Connect

    Antoine, M.H.; Hermann, M.; Herchuelz, A.; Lebrun, P. )

    1991-07-01

    Minoxidil sulfate is an antihypertensive agent belonging to the new class of vasodilators, the K+ channel openers. The present study was undertaken to characterize the effects of minoxidil sulfate on ionic and secretory events in rat pancreatic islets. The drug unexpectedly provoked a concentration-dependent decrease in 86Rb outflow. This inhibitory effect was reduced in a concentration-dependent manner by glucose and tolbutamide. Minoxidil sulfate did not affect 45Ca outflow from islets perfused in the presence of extracellular Ca++ and absence or presence of glucose. However, in islets exposed to a medium deprived of extracellular Ca++, the drug provoked a rise in 45Ca outflow. Whether in the absence or presence of extracellular Ca++, minoxidil sulfate increased the cytosolic free Ca++ concentration of islet cells. Lastly, minoxidil sulfate increased the release of insulin from glucose-stimulated pancreatic islets. These results suggest that minoxidil sulfate reduces the activity of the ATP-sensitive K+ channels and promotes an intracellular translocation of Ca++. The latter change might account for the effect of the drug on the insulin-releasing process. However, the secretory response to minoxidil sulfate could also be mediated, at least in part, by a modest Ca++ entry.

  18. The electrostatic basis for the interfacial binding of secretory phospholipases A2.

    PubMed Central

    Scott, D L; Mandel, A M; Sigler, P B; Honig, B

    1994-01-01

    Biochemical and structural data suggest that electrostatic forces play a critical role in the binding of secretory phospholipases A2 to substrate aggregates (micelles, vesicles, monolayers, and membranes). This initial binding (adsorption) of the enzyme to the interface is kinetically distinct from the subsequent binding of substrate to the buried active site. Thus, in the absence of specific active-site interactions, electrostatic forces operating at the molecular surface may orient and hold the enzyme at the interface. We have calculated the electrostatic potentials for 10 species of secretory phospholipases A2 whose atomic coordinates have been determined by x-ray crystallography. Most of these enzymes show a marked electrostatic sidedness that is accentuated to a variable degree by the presence of the essential cofactor calcium ion. This asymmetry suggests a discrete interfacial binding region on the protein's surface, the location of which is in general agreement with proposals derived from the results of chemical modification, mutational, and crystallographic experiments. Images FIGURE 2 FIGURE 3 FIGURE 3 FIGURE 3 FIGURE 4 FIGURE 4 FIGURE 5 FIGURE 5 PMID:7948668

  19. Ovulation in Drosophila is controlled by secretory cells of the female reproductive tract.

    PubMed

    Sun, Jianjun; Spradling, Allan C

    2013-01-01

    How oocytes are transferred into an oviduct with a receptive environment remains poorly known. We found that glands of the Drosophila female reproductive tract, spermathecae and/or parovaria, are required for ovulation and to promote sperm storage. Reducing total secretory cell number by interferring with Notch signaling during development blocked ovulation. Knocking down expression after adult eclosion of the nuclear hormone receptor Hr39, a master regulator of gland development, slowed ovulation and blocked sperm storage. However, ovulation (but not sperm storage) continued when only canonical protein secretion was compromised in adult glands. Our results imply that proteins secreted during adulthood by the canonical secretory pathway from female reproductive glands are needed to store sperm, while a non-canonical glandular secretion stimulates ovulation. Our results suggest that the reproductive tract signals to the ovary using glandular secretions, and that this pathway has been conserved during evolution. DOI:http://dx.doi.org/10.7554/eLife.00415.001. PMID:23599892

  20. Purification and characterization of a secretory lipolytic enzyme, MgLIP2, from Malassezia globosa.

    PubMed

    Juntachai, Weerapong; Oura, Takahiro; Kajiwara, Susumu

    2011-12-01

    Malassezia globosa is a lipid-dependent yeast that is found on the human skin and is associated with various skin disorders, including dandruff and seborrhoeic dermatitis (SD). Despite its important role in skin diseases, the molecular basis for its pathogenicity is poorly understood. The current hypothesis is that dandruff and SD are linked to fatty acid metabolism and secretory lipolytic enzymes, which hydrolyse sebaceous lipids and release irritating free fatty acids. A previous genomic analysis of M. globosa identified a family of 13 homologous genes predicted to encode secreted lipases. We have also reported that M. globosa had significantly higher extracellular lipase activity compared with other species. To identify the major secretory lipases of this yeast during its growth, we successfully purified and characterized an extracellular lipase MgLIP2. Based on MALDI-TOF MS, the peptide mass fingerprint of a tryptically digested protein MgLIP2 corresponded to ORF MGL_4054 of M. globosa. This lipase showed high esterase activity against 4-nitrophenyl palmitate and 1-naphthyl palmitate but not 1-naphthyl acetate. This enzyme had optimal activity at 30 °C and pH 5.0. Furthermore, the activity significantly increased in the presence of Triton X-100 and was partially inhibited by PMSF but was unaffected by univalent and divalent metal ions. PMID:22016565

  1. Mouse Paneth Cell Secretory Responses to Cell Surface Glycolipids of Virulent and Attenuated Pathogenic Bacteria

    PubMed Central

    Tanabe, Hiroki; Ayabe, Tokiyoshi; Bainbridge, Brian; Guina, Tina; Ernst, Robert K.; Darveau, Richard P.; Miller, Samuel I.; Ouellette, Andre J.

    2005-01-01

    Mouse Paneth cells respond to bacteria and bacterial cell surface antigens by discharging secretory granules into the lumen of small intestinal crypts (T. Ayabe et al., Nat. Immunol. 1:113-118, 2000). To investigate mechanisms regulating these responses, purified surface glycolipid molecules with known acyl chain modifications and attenuated properties were tested for the ability to stimulate Paneth cell secretion. The antigens included lipopolysaccharide (LPS) from wild-type and msbB-null Escherichia coli and phoP-null and phoP-constitutive Salmonella enterica serovar Typhimurium strains, as well as LPS, lipid A, and lipoteichoic acid from Pseudomonas aeruginosa and Listeria monocytogenes grown in Mg2+-limited media. Measurements of total secreted protein, secreted lysozyme, and the bactericidal peptide activities of collected secretions showed that the purified antigens elicited similar secretory responses from Paneth cells in mouse crypts ex vivo, regardless of glycolipid acyl chain modification. Despite their impaired Tlr4 pathway, Paneth cells in ex vivo C3H/HeJ mouse crypts released equivalent amounts of bactericidal peptide activity in response to purified bacterial antigens, including lipid A. Thus, mouse Paneth cells respond equivalently to purified bacterial cell envelope glycolipids, regardless of functional Tlr4, the structural properties of glycolipid acyl chains, or their association with virulence in humans. PMID:15784576

  2. Macrophage response to bacteria: induction of marked secretory and cellular activities by lipoteichoic acids.

    PubMed Central

    Keller, R; Fischer, W; Keist, R; Bassetti, S

    1992-01-01

    Lipoteichoic acids (LTAs) from various bacterial species, including Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumoniae, Enterococcus faecalis, and Listeria monocytogenes, were examined for the ability to induce secretory and cellular responses in a pure population of bone marrow-derived mononuclear phagocytes. Some of the highly purified LTAs, in particular LTAs from Bacillus subtilis, S. pyogenes, E. faecalis, and Enterococcus hirae, were able to affect each of the macrophage parameters measured, i.e., reductive capacity, secretion of tumor necrosis factor and nitrite, and tumoricidal activity. As after stimulation with whole organisms or other bacterial products, secretion of tumor necrosis factor induced by these LTAs reached its maximum within the first few hours of the interaction, while secretion of nitrite and tumoricidal activity required 24 to 36 h for full expression. Other purified LTAs, i.e., LTAs from Streptococcus sanguis, S. pneumoniae, and L. monocytogenes, as well as lipomannan from Micrococcus luteus affected only some of these parameters, while native LTA from S. aureus was inactive. There was no obvious correlation between biological activity and chain length, kind of glycosyl substituents, glycolipid structures, or fatty acid composition of LTAs. Deacylation of LTAs resulted in a complete loss of activity, and deacylated LTAs did not impair the activity of their acylated counterparts, suggesting that acyl chains may be essential for binding of LTA to the cell surface. The results demonstrate that some LTA species are potent inducers of macrophage secretory and cellular activities. PMID:1500175

  3. Modeling F-actin cortex influence on the secretory properties of neuroendocrine cells

    PubMed Central

    Gil, Amparo

    2011-01-01

    Chromaffin cells are considered as one of the most valuable models to study regulated exocytosis. In these cells, like in other neuroendocrine systems, an intricate cortical cytoskeleton acts as a retentive network impeding vesicle access to plasma membrane. Therefore, during stimulation this structure suffers a transient reorganization allowing active transport of vesicles toward secretory sites. Interestingly, a combination of confocal microscopy studies and mathematical modeling is showing us new aspects of the influence of cortical cytoskeleton in shaping the secretory properties of excitable cells. In this new vision the F-actin-myosin II cortical cytoskeleton is organized forming polygonal cages with the molecular machinery of exocytosis composed by SNARE proteins and voltage-dependent calcium channels associating with its border. In this way the cytoskeleton not only holds together the essential elements acting during secretion, but we proposed that could also act as a structural factor opposing to the free diffusion of the calcium signal and therefore sustains high levels of the intracellular signal triggering exocytosis. PMID:21966558

  4. A parametric study of planform and aeroelastic effects on aerodynamic center, alpha- and q- stability derivatives. Appendix C: Method for computing the aerodynamic influence coefficient matrix of nonplanar wing-body-tail configurations

    NASA Technical Reports Server (NTRS)

    Roskam, J.

    1972-01-01

    Expressions are derived for computing the aerodynamic influence coefficient matrix for nonplanar wing-body-tail configurations. An aerodynamic influence coefficient is defined as the load in lbs. induced on a panel as a result of a unit angle of attack on another panel. Fuselage, wing and tail thickness are assumed to be small with the result that the thickness effect on the flow-field is negligible. The method for determining the aerodynamic influence coefficient matrix is based on the lifting solution to the small perturbation, steady potential flow equation.

  5. Beta-agonists and secretory cell number and intracellular glycoproteins in airway epithelium. The effect of isoproterenol and salbutamol.

    PubMed Central

    Jones, R.; Reid, L.

    1979-01-01

    This study describes the effect of systemic administration of the beta-adrenergic agonists isoproterenol and salbutamol on the secretory cell populations in seven regions of rat airway epithelium (three extrapulmonary and four intrapulmonary) and on the size of salivary glands and heart. Isoproterenol (a nonselective beta-adrenergic agonist) significantly increases secretory cell number in all airway regions except the midtrachea; salbutamol (a selective beta 2 agonist) increases secretory cell number only in proximal and peripheral regions. The absolute number of secretory cells is greatest in the most peripheral region after isoproterenol administration and in the most proximal region after salbutamol, although both drugs produce the greatest relative increase at the periphery. In proximal and, particularly, peripheral regions, the increase by isoproterenol (less than 3- and 14-fold, respectively) is greater than by salbutamol (less than 2- and less than 3-fold, respectively). In all airway regions, both drugs modify intracellular glycoprotein in the secretory cell population; within a given region, modification is much the same. In the most proximal region, the population of cells synthesizing only granules of neutral glycoprotein significantly increases while in other regions increase is in cells synthesizing only granules of acid. A significant shift in glycoprotein synthesis occurs whether or not the secretory cell population is increased, which suggests that existing as well as newly appearing cells modify their product. Isoproterenol significantly increases the size of the parotid and submaxillary glands; salbutamol increases the size of the parotid only. Isoproterenol significantly increases the weight of both ventricles of the heart; salbutamol has no such effect. PMID:36762

  6. The Ca2+/H+ antiporter TMEM165 expression, localization in the developing, lactating and involuting mammary gland parallels the secretory pathway Ca2+ATPase (SPCA1)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plasma membrane Ca2+-ATPase 2 (PMCA2) knockout mice showed that ~ 60 % of calcium in milk is transported across the mammary cells apical membrane by PMCA2. The remaining milk calcium is thought to arrive via the secretory pathway through the actions of secretory pathway Ca2+-ATPase’s 1 and/or 2 (SP...

  7. Episodic slow slip process in a non-planar fault model constrained by non-volcanic tremor locations along Cascadia subduction zone

    NASA Astrophysics Data System (ADS)

    Li, D.; Liu, Y.

    2015-12-01

    Slow slip events (SSEs) are observed in the circum-Pacific subduction zones and exhibit a wide diversity of source parameters (including equivalent moment, duration and recurrence interval). Gao et al [2012] compiled source parameters of SSEs around the world and revealed their empirical scaling relations distinct from those of regular earthquakes. However, the nature of this diversity is unclear. Previous 3-D numerical simulations in a simplified plate model have reproduced the along-strike segmentation of episodic SSEs in Cascadia margin and their source scaling relations in the framework of rate- and state- friction law [Liu, 2014]. But the planar fault model is inefficient to investigate the effect of the fault geometry on the source characteristics of SSEs in a specific subduction zone. In this study, we adopt a non-planar Cascadia subduction fault geometry constrained by relocated seismicity [McCrory et al. 2012] in the rate-state friction model. We have reproduced episodic SSEs beneath Vancouver Island and Washington arising every ~1.5 year with a maximum cumulative slip of ~2.5 cm. We find three phases characteristic in cumulative moment rate and slip rate in each episode. These three phases, defined as nucleation, fast-spreading and healing, lasting for ~160, ~60 and ~140 days, respectively. Both the nucleation and healing phases are beneath GPS detection threshold but the nucleation phase is spatially correlated with the small tremor activities arising deeper than episodic tremor and slip (ETS). To further investigate the diversity of SSEs in Cascadia, we introduce the recent 6-year tremor locations in Cascadia (http://pnsn.org/tremor) to constrain the near-lithostatic pore pressure distribution at the SSE depths in an 800km-long Cascadia fault model. Additionally, we set a step change of effective normal stress in SSE region from 1.5 MPa in Vancouver Island and Washington to 2.0 MPa in Oregon. The results show that the modeled SSEs exhibit distinct slip

  8. Simultaneous monitoring of electrical and secretory activity in peptidergic neurosecretory terminals of the crab.

    PubMed Central

    Stuenkel, E L

    1985-01-01

    Intracellularly recorded responses of peptidergic neurosecretory terminals and somata were correlated with their secretory responsiveness to elevation of the external K concentration ([K+]o). The experiments were performed on in vitro X-organ sinus gland neurosecretory systems from the eyestalk of the crab Cardisoma carnifex. Elevated-K-evoked release was followed in preparations exposed to a pulse-chase radiolabelling regime. The release of [3H]leucine incorporated into neurosecretory peptides could be followed by collecting the separate perfusates of the somata and terminal regions. Elevation of the [K+]o evoked terminal depolarization, an increase in impulse firing frequency and a decrease (50%) in terminal input resistance. Impulse firing ceased (in ca. 2 min) as depolarization reached a sustained maximum level (-17.6 +/- 3.57 mV, n = 9, absolute potential). The terminal depolarization and decreased input resistance were maintained throughout the period of elevated-K treatment. Release from the terminal region of incorporated 3H label paralleled the simultaneously monitored terminal depolarization. Maintained exposure to elevated-K saline was accompanied by sustained high levels of 3H release continuing beyond the loss of regenerative membrane responses. Release declined with a half-time of 47.1 +/- 13.5 min (n = 7). In contrast, terminal release of red pigment concentrating hormone (RPCH) was transitory, reaching peak values and declining to base line within a 10 min period. Removal of external Ca or addition of the Ca antagonists, Cd or Mn, blocked the stimulated 3H release. Addition of Cd or Mn, prior to or during an elevated-K-evoked 3H release produced a reversible suppression of the secretory response. Stimulation in the absence of external Na, under normal Ca conditions, resulted in a normal secretory response. The amplitude and duration of the elevated-K-evoked terminal depolarization was unaffected by nominally Ca- or Na-free saline or addition of Cd

  9. Ionic dependence of secretory and electrical activity evoked by elevated K+ in a peptidergic neurosecretory system.

    PubMed

    Cooke, I M; Haylett, B A

    1984-11-01

    Secretion of the octapeptide erythrophore- (red pigment-) concentrating hormone (ECH, RPCH) and extracellularly monitored electrical activity were followed simultaneously from individual, isolated sinus glands (neurohaemal organs), of the crab Cardisoma carnifex. Following introduction of saline having elevated [K], 100-196 mmol l-1 (5-11 X normal), secretion (bioassayed from 1-min fractions during continuous perfusion) increases from barely detectable (less than 1 fmol min-1) to a peak, average 31 fmol min-1, within 5 min, and immediately subsides. Additional responses are obtainable following a period, greater than 30 min, of normal saline perfusion. Secretory responses to K are Ca-dependent. If Ca is restored (in high K) following perfusion in 0-Ca, high K, only a small secretory response is observed. Addition of Mn (10 mmol l-1, normal Ca) reduces secretion to one-tenth. Increased net uptake of 45Ca of 2.5- to 6-fold is observed in individual sinus glands exposed to 10 X K compared to paired, unstimulated organs. The pattern and Ca-dependence of secretory responses to K are unaffected, but the amount of secretion is augmented in Na-deficient or TTX-containing salines. Intracellular recording confirms that brief (10-40 s) bouts of intense firing recorded extracellularly upon commencing a high K perfusion include repetitive firing by terminals, superimposed on rapid depolarization. Firing ceases as the membrane potential reaches a depolarized value (-18 to -15 mV for [K] 100-176 mmol l-1), which is then maintained until restoration of normal saline, when slow repolarization ensues. In 0-Ca, spontaneous impulse firing is increased, resting potential depolarized by 5 to 15 mV, but the bout of impulse firing and the maintained depolarization in response to K are similar. Thus, mechanisms of secretion of a crustacean peptide neurohormone appear closely similar to those of other systems characterized: responsiveness to elevated K, dependence on Ca, depolarization

  10. Simultaneous monitoring of electrical and secretory activity in peptidergic neurosecretory terminals of the crab.

    PubMed

    Stuenkel, E L

    1985-02-01

    Intracellularly recorded responses of peptidergic neurosecretory terminals and somata were correlated with their secretory responsiveness to elevation of the external K concentration ([K+]o). The experiments were performed on in vitro X-organ sinus gland neurosecretory systems from the eyestalk of the crab Cardisoma carnifex. Elevated-K-evoked release was followed in preparations exposed to a pulse-chase radiolabelling regime. The release of [3H]leucine incorporated into neurosecretory peptides could be followed by collecting the separate perfusates of the somata and terminal regions. Elevation of the [K+]o evoked terminal depolarization, an increase in impulse firing frequency and a decrease (50%) in terminal input resistance. Impulse firing ceased (in ca. 2 min) as depolarization reached a sustained maximum level (-17.6 +/- 3.57 mV, n = 9, absolute potential). The terminal depolarization and decreased input resistance were maintained throughout the period of elevated-K treatment. Release from the terminal region of incorporated 3H label paralleled the simultaneously monitored terminal depolarization. Maintained exposure to elevated-K saline was accompanied by sustained high levels of 3H release continuing beyond the loss of regenerative membrane responses. Release declined with a half-time of 47.1 +/- 13.5 min (n = 7). In contrast, terminal release of red pigment concentrating hormone (RPCH) was transitory, reaching peak values and declining to base line within a 10 min period. Removal of external Ca or addition of the Ca antagonists, Cd or Mn, blocked the stimulated 3H release. Addition of Cd or Mn, prior to or during an elevated-K-evoked 3H release produced a reversible suppression of the secretory response. Stimulation in the absence of external Na, under normal Ca conditions, resulted in a normal secretory response. The amplitude and duration of the elevated-K-evoked terminal depolarization was unaffected by nominally Ca- or Na-free saline or addition of Cd

  11. Characterisation of a secretory serine protease inhibitor (SjB6) from Schistosoma japonicum

    PubMed Central

    2014-01-01

    Background Proteins belonging to the serine protease inhibitor (serpin) superfamily play essential physiological roles in many organisms. In pathogens, serpins are thought to have evolved specifically to limit host immune responses by interfering with the host immune-stimulatory signals. Serpins are less well characterised in parasitic helminths, although some are thought to be involved in mechanisms associated with host immune modulation. In this study, we cloned and partially characterised a secretory serpin from Schistosoma japonicum termed SjB6, these findings provide the basis for possible functional roles. Methods SjB6 gene was identified through database mining of our previously published microarray data, cloned and detailed sequence and structural analysis and comparative modelling carried out using various bioinformatics and proteomics tools. Gene transcriptional profiling was determined by real-time PCR and the expression of native protein determined by immunoblotting. An immunological profile of the recombinant protein produced in insect cells was determined by ELISA. Results SjB6 contains an open reading frame of 1160 base pairs that encodes a protein of 387 amino acid residues. Detailed sequence analysis, comparative modelling and structural-based alignment revealed that SjB6 contains the essential structural motifs and consensus secondary structures typical of inhibitory serpins. The presence of an N-terminal signal sequence indicated that SjB6 is a secretory protein. Real-time data indicated that SjB6 is expressed exclusively in the intra-mammalian stage of the parasite life cycle with its highest expression levels in the egg stage (p < 0.0001). The native protein is approximately 60 kDa in size and recombinant SjB6 (rSjB6) was recognised strongly by sera from rats experimentally infected with S. japonicum. Conclusions The significantly high expression of SjB6 in schistosome eggs, when compared to other life cycle stages, suggests a possible

  12. Senescent Vascular Smooth Muscle Cells Drive Inflammation Through an Interleukin-1α–Dependent Senescence-Associated Secretory Phenotype

    PubMed Central

    Gardner, Sarah E.; Humphry, Melanie; Bennett, Martin R.

    2015-01-01

    Objective— Vascular smooth muscle cells (VSMCs) that become senescent are both present within atherosclerotic plaques and thought to be important to the disease process. However, senescent VSMCs are generally considered to only contribute through inaction, with failure to proliferate resulting in VSMC- and collagen-poor unstable fibrous caps. Whether senescent VSMCs can actively contribute to atherogenic processes, such as inflammation, is unknown. Approach and Results— We find that senescent human VSMCs develop a proinflammatory state known as a senescence-associated secretory phenotype. Senescent human VSMCs release high levels of multiple cytokines and chemokines driven by secreted interleukin-1α acting in an autocrine manner. Consequently, the VSMC senescence-associated secretory phenotype promotes chemotaxis of mononuclear cells in vitro and in vivo. In addition, senescent VSMCs release active matrix metalloproteinase-9, secrete less collagen, upregulate multiple inflammasome components, and prime adjacent endothelial cells and VSMCs to a proadhesive and proinflammatory state. Importantly, maintaining the senescence-associated secretory phenotype places a large metabolic burden on senescent VSMCs, such that they can be selectively killed by inhibiting glucose utilization. Conclusions— Senescent VSMCs may actively contribute toward the chronic inflammation associated with atherosclerosis through the interleukin-1α–driven senescence-associated secretory phenotype and the priming of adjacent cells to a proatherosclerotic state. These data also suggest that inhibition of this potentially important source of chronic inflammation in atherosclerosis requires blockade of interleukin-1α and not interleukin-1β. PMID:26139463

  13. The secretory membrane system in the Drosophila syncytial blastoderm embryo exists as functionally compartmentalized units around individual nuclei

    PubMed Central

    Frescas, David; Mavrakis, Manos; Lorenz, Holger; DeLotto, Robert; Lippincott-Schwartz, Jennifer

    2006-01-01

    Drosophila melanogaster embryogenesis begins with 13 nuclear division cycles within a syncytium. This produces >6,000 nuclei that, during the next division cycle, become encased in plasma membrane in the process known as cellularization. In this study, we investigate how the secretory membrane system becomes equally apportioned among the thousands of syncytial nuclei in preparation for cellularization. Upon nuclear arrival at the cortex, the endoplasmic reticulum (ER) and Golgi were found to segregate among nuclei, with each nucleus becoming surrounded by a single ER/Golgi membrane system separate from adjacent ones. The nuclear-associated units of ER and Golgi across the syncytial blastoderm produced secretory products that were delivered to the plasma membrane in a spatially restricted fashion across the embryo. This occurred in the absence of plasma membrane boundaries between nuclei and was dependent on centrosome-derived microtubules. The emergence of secretory membranes that compartmentalized around individual nuclei in the syncytial blastoderm is likely to ensure that secretory organelles are equivalently partitioned among nuclei at cellularization and could play an important role in the establishment of localized gene and protein expression patterns within the early embryo. PMID:16636144

  14. Cathepsin L in secretory vesicles functions as a prohormone-processing enzyme for production of the enkephalin peptide neurotransmitter

    PubMed Central

    Yasothornsrikul, Sukkid; Greenbaum, Doron; Medzihradszky, Katalin F.; Toneff, Thomas; Bundey, Richard; Miller, Ruthellen; Schilling, Birgit; Petermann, Ivonne; Dehnert, Jessica; Logvinova, Anna; Goldsmith, Paul; Neveu, John M.; Lane, William S.; Gibson, Bradford; Reinheckel, Thomas; Peters, Christoph; Bogyo, Matthew; Hook, Vivian

    2003-01-01

    Multistep proteolytic mechanisms are essential for converting proprotein precursors into active peptide neurotransmitters and hormones. Cysteine proteases have been implicated in the processing of proenkephalin and other neuropeptide precursors. Although the papain family of cysteine proteases has been considered the primary proteases of the lysosomal degradation pathway, more recent studies indicate that functions of these enzymes are linked to specific biological processes. However, few protein substrates have been described for members of this family. We show here that secretory vesicle cathepsin L is the responsible cysteine protease of chromaffin granules for converting proenkephalin to the active enkephalin peptide neurotransmitter. The cysteine protease activity was identified as cathepsin L by affinity labeling with an activity-based probe for cysteine proteases followed by mass spectrometry for peptide sequencing. Production of [Met]enkephalin by cathepsin L occurred by proteolytic processing at dibasic and monobasic prohormone-processing sites. Cellular studies showed the colocalization of cathepsin L with [Met]enkephalin in secretory vesicles of neuroendocrine chromaffin cells by immunofluorescent confocal and immunoelectron microscopy. Functional localization of cathepsin L to the regulated secretory pathway was demonstrated by its cosecretion with [Met]enkephalin. Finally, in cathepsin L gene knockout mice, [Met]enkephalin levels in brain were reduced significantly; this occurred with an increase in the relative amounts of enkephalin precursor. These findings indicate a previously uncharacterized biological role for secretory vesicle cathepsin L in the production of [Met]enkephalin, an endogenous peptide neurotransmitter. PMID:12869695

  15. Intestinal Neurogenin 3 Directs Differentiation of a Bipotential Secretory Progenitor to Endocrine Cell Rather than Goblet Cell Fate

    PubMed Central

    López-Díaz, Lymari; Jain, Renu N.; Keeley, Theresa M.; VanDussen, Kelli L.; Brunkan, Cynthia S.; Gumucio, Deborah L.; Samuelson, Linda C.

    2009-01-01

    Neurogenin 3 is essential for enteroendocrine cell development; however, it is unknown whether this transcription factor is sufficient to induce an endocrine program in the intestine or how it affects the development of other epithelial cells originating from common progenitors. In this study, the mouse villin promoter was used to drive Neurogenin 3 expression throughout the developing epithelium to measure the affect on cell fate. Although the general morphology of the intestine was unchanged, transgenic founder embryos displayed increased numbers of cells expressing the pan-endocrine marker chromogranin A. Accordingly, expression of several hormones and pro-endocrine transcription factors were increased in the transgenics suggesting that Neurogenin 3 stimulated a program of terminal enteroendocrine cell development. To test whether increased endocrine cell differentiation affected the development of other secretory cell lineages, we quantified goblet cells, the only other secretory cell formed in embryonic intestine. The Neurogenin 3-expressing transgenics had decreased numbers of goblet cells in correspondence to the increase in endocrine cells, with no change in the total secretory cell numbers. Thus, our data suggest that Neurogenin 3 can redirect the differentiation of bipotential secretory progenitors to endocrine rather than goblet cell fate. PMID:17706959

  16. Peptidyl-glycine alpha-amidating monooxygenase is present in islet secretory granules of the anglerfish, Lophius americanus.

    PubMed

    Mackin, R B; Flacker, J M; Mackin, J A; Noe, B D

    1987-08-01

    Anglerfish islet secretory granules have been examined for the presence of an enzyme which could perform C-terminal amidation of glucagon-like peptide II and possibly anglerfish peptide Y. Using [125I]D-Tyr-Val-Gly as substrate, a peptidyl-glycine alpha-amidating monooxygenase (PAM) was detected in islet secretory granule lysates. The enzyme is active between pH 6.0 and 8.5 and exhibits maximal activity near pH 7.0. The islet PAM requires Cu2+, ascorbate, and molecular oxygen for activity. Other divalent metal ions and redox cofactors were tested and found to be inactive in the assay. Even though added Cu2+ and ascorbate are required for detecting islet PAM activity, when these factors were incubated with substrate in the absence of secretory granule lysate, no activity was observed. It was also found that the addition of higher than optimal concentrations of either Cu2+ or ascorbate inhibited amidating activity. The results demonstrate that a PAM is present in secretory granules of anglerfish islet tissue. The characteristics of the islet PAM are similar to those of PAMs identified and characterized in other tissues which produce bioactive C-terminally amidated peptides. PMID:3305155

  17. Cathepsin L participates in the production of neuropeptide Y in secretory vesicles, demonstrated by protease gene knockout and expression.

    PubMed

    Funkelstein, Lydiane; Toneff, Thomas; Hwang, Shin-Rong; Reinheckel, Thomas; Peters, Christoph; Hook, Vivian

    2008-07-01

    Neuropeptide Y (NPY) functions as a peptide neurotransmitter and as a neuroendocrine hormone. The active NPY peptide is generated in secretory vesicles by proteolytic processing of proNPY. Novel findings from this study show that cathepsin L participates as a key proteolytic enzyme for NPY production in secretory vesicles. Notably, NPY levels in cathepsin L knockout (KO) mice were substantially reduced in brain and adrenal medulla by 80% and 90%, respectively. Participation of cathepsin L in producing NPY predicts their colocalization in secretory vesicles, a primary site of NPY production. Indeed, cathepsin L was colocalized with NPY in brain cortical neurons and in chromaffin cells of adrenal medulla, demonstrated by immunofluorescence confocal microscopy. Immunoelectron microscopy confirmed the localization of cathepsin L with NPY in regulated secretory vesicles of chromaffin cells. Functional studies showed that coexpression of proNPY with cathepsin L in neuroendocrine PC12 cells resulted in increased production of NPY. Furthermore, in vitro processing indicated cathepsin L processing of proNPY at paired basic residues. These findings demonstrate a role for cathepsin L in the production of NPY from its proNPY precursor. These studies illustrate the novel biological role of cathepsin L in the production of NPY, a peptide neurotransmitter, and neuroendocrine hormone.

  18. Secretory Pathway-Dependent Localization of the Saccharomyces cerevisiae Rho GTPase-Activating Protein Rgd1p at Growth Sites

    PubMed Central

    Lefèbvre, Fabien; Prouzet-Mauléon, Valérie; Hugues, Michel; Crouzet, Marc; Vieillemard, Aurélie; McCusker, Derek; Thoraval, Didier

    2012-01-01

    Establishment and maintenance of cell polarity in eukaryotes depends upon the regulation of Rho GTPases. In Saccharomyces cerevisiae, the Rho GTPase activating protein (RhoGAP) Rgd1p stimulates the GTPase activities of Rho3p and Rho4p, which are involved in bud growth and cytokinesis, respectively. Consistent with the distribution of Rho3p and Rho4p, Rgd1p is found mostly in areas of polarized growth during cell cycle progression. Rgd1p was mislocalized in mutants specifically altered for Golgi apparatus-based phosphatidylinositol 4-P [PtdIns(4)P] synthesis and for PtdIns(4,5)P2 production at the plasma membrane. Analysis of Rgd1p distribution in different membrane-trafficking mutants suggested that Rgd1p was delivered to growth sites via the secretory pathway. Rgd1p may associate with post-Golgi vesicles by binding to PtdIns(4)P and then be transported by secretory vesicles to the plasma membrane. In agreement, we show that Rgd1p coimmunoprecipitated and localized with markers specific to secretory vesicles and cofractionated with a plasma membrane marker. Moreover, in vivo imaging revealed that Rgd1p was transported in an anterograde manner from the mother cell to the daughter cell in a vectoral manner. Our data indicate that secretory vesicles are involved in the delivery of RhoGAP Rgd1p to the bud tip and bud neck. PMID:22447923

  19. Sorting of cyst wall proteins to a regulated secretory pathway during differentiation of the primitive eukaryote, Giardia lamblia.

    PubMed

    Reiner, D S; McCaffery, M; Gillin, F D

    1990-10-01

    Giardia lamblia, which belongs to the earliest identified lineage to diverge from the eukaryotic line of descent, is one of many protists reported to lack a Golgi apparatus. Our recent finding of a developmentally regulated secretory pathway in G. lamblia makes it an ideal organism with which to test the hypothesis that the Golgi may be more readily demonstrated in actively secreting cells. These ultrastructural studies now show that a regulated pathway of transport and secretion of cyst wall antigens via a novel class of large, osmiophilic secretory vesicles, the encystation-specific vesicles (ESV), is assembled during encystation of G. lamblia. Early in encystation, cyst antigens are localized in simple Golgi membrane stacks and concentrated within enlarged Golgi cisternae which appear to be precursors of ESV. This would represent an unusual mechanism of secretory vesicle biogenesis. Later in differentiation, cyst antigens are localized within ESV, which transport them to the plasma membrane and release them by exocytosis to the nascent cell wall. ESV are not observed after completion of the cyst wall. In contrast to the regulated transport of cyst wall proteins, we demonstrate a distinct constitutive lysosomal pathway. During encystation, acid phosphatase activity is localized in endoplasmic reticulum, Golgi, and small constitutive peripheral vacuoles which function as lysosomes. However, acid phosphatase activity is not detectable in ESV. These studies show that G. lamblia, an early eukaryote, is capable of carrying out Golgi-mediated sorting of proteins to distinct regulated secretory and constitutive lysosomal pathways.

  20. Effects of Cichorium Intybus L. Root Extract on Secretory Activity of the Stomach in Health and Ulcer Disease.

    PubMed

    Krylova, S G; Vymyatnina, Z K; Zueva, E P; Amosova, E N; Razina, T G; Litvinenko, V I

    2015-09-01

    Gastroprotective effect of Cichorium intybus L. root extract is demonstrated on H. Shay's model of experimental ulcer in rats. The effect is attributed to the antisecretory activity of the plant and stimulation of defense barrier function of the gastric mucosa. The regulatory effect of the phytocomplex on seasonal characteristics of the gastric secretory and defense functions in dogs with Basov's fistula is detected.

  1. [Restoration of secretory activity of digestive glands in conditions of acute hyperkinesis at persons with different levels of motor activity].

    PubMed

    Griaznykh, A V

    2012-01-01

    The dynamics' features of restoration reactions of the secretory function of gastric glands have been studied at patients with differences in the level and specificity of daily physical activity. The dependence between the level and characteristics of daily physical activity and reactivity of the secretory apparatus of the gastric glands in the recovery period after the muscle load has been established. The high reactivity of the secretory activity of digestive glands is typical for individuals with high level of daily physical activity. The differences of the functional stability of the secretion's mechanisms of various components of gastric juice under the influence of physical exercise and in recovery have been revealed. The greatest stability of the secretory mechanisms of digestive glands has been discovered at athletes practicing with the development of endurance--at skiers. Heterochronous reducing reactions of gastric and pancreatic secretion after physical stress have been defined. The reduction of secretion's mechanisms of gastric juice ingredients and the electrolyte and acid composition of digestive juices isn't simultaneous: the first order is for ferment's secretion. The inverse relationship between the content of digestive enzymes pepsinogen-1 and -2 in blood's serum and the concentration of proteolytic enzymes in the gastric content has been found at persons with various degrees of adaptation to the muscular tension.

  2. Non-Secretory Myeloma, Diagnosed on Renal Biopsy as Cast Nephropathy.

    PubMed

    Grover, Sumit; Selhi, Pavneet Kaur; Sood, Neena; Sandhu, Jasvinder Singh; Kaur, Harpreet

    2016-06-01

    Multiple myeloma is a disorder of plasma cells which can involve kidneys in the form of cast nephropathy. Neoplastic plasma cells produce either complete immunoglobulins or fragments of immunoglobulins leading to a monoclonal spike in the serum and/or Bence Jones proteinuria. Very few patients present as non-secretory myeloma when no immunoglobulins (M spike) are produced or only light chains are secreted which can only be detected in urine. Acute renal failure due to cast nephropathy can rarely be the first presentation of multiple myeloma. We here in report a case in which primary diagnosis of multiple myeloma was made on renal biopsy due to its characteristic histomorphology. The diagnosis was later on supported by presence of neoplastic plasma cells in the aspirate and biopsy of bone marrow. PMID:27504298

  3. Isoprenoid biosynthesis. Metabolite profiling of peppermint oil gland secretory cells and application to herbicide target analysis.

    PubMed

    Lange, B M; Ketchum, R E; Croteau, R B

    2001-09-01

    Two independent pathways operate in plants for the synthesis of isopentenyl diphosphate and dimethylallyl diphosphate, the central intermediates in the biosynthesis of all isoprenoids. The mevalonate pathway is present in the cytosol, whereas the recently discovered mevalonate-independent pathway is localized to plastids. We have used isolated peppermint (Mentha piperita) oil gland secretory cells as an experimental model system to study the effects of the herbicides fosmidomycin, phosphonothrixin, methyl viologen, benzyl viologen, clomazone, 2-(dimethylamino)ethyl diphosphate, alendronate, and pamidronate on the pools of metabolites related to monoterpene biosynthesis via the mevalonate-independent pathway. A newly developed isolation protocol for polar metabolites together with an improved separation and detection method based on liquid chromatography-mass spectrometry have allowed assessment of the enzyme targets for a number of these herbicides.

  4. Redirection of peroxisomal alcohol oxidase of Hansenula polymorpha to the secretory pathway.

    PubMed

    van der Heide, Meis; Leão, Adriana N; Van der Klei, Ida J; Veenhuis, Marten

    2007-10-01

    We report on the rerouting of peroxisomal alcohol oxidase (AO) to the secretory pathway of Hansenula polymorpha. Using the leader sequence of the Saccharomyces cerevisiae mating factor alpha (MFalpha) as sorting signal, AO was correctly sorted to the endoplasmic reticulum (ER), which strongly proliferated in these cells. The MFalpha presequence, but not the prosequence, was cleaved from the protein. AO protein was present in the ER as monomers that lacked FAD, and hence was enzymatically inactive. Furthermore, the recombinant AO protein was subject to gradual degradation, possibly because the protein did not fold properly. However, when the S. cerevisiae invertase signal sequence (ISS) was used, secretion of AO protein was observed in conjunction with bulk of the protein being localized to the ER. The amount of secreted AO protein increased with increasing copy numbers of the AO expression cassette integrated into the genome. The secreted AO protein was correctly processed and displayed enzyme activity. PMID:17419772

  5. Inhibitory effect of polyozellin on secretory group IIA phospholipase A2.

    PubMed

    Ku, Sae-Kwang; Yang, Eun-Ju; Kang, Hyejin; Jung, Byeongjin; Bae, Jong-Sup

    2016-02-01

    The expression of secretory group IIA phospholipase A2 (sPLA2-IIA) is enhanced by development of inflammatory disorders. In this study, sPLA2-IIA expression was induced in the lipopolysaccharide (LPS)-stimulated human umbilical vein endothelial cells and mice to evaluate the effect of polyozellin. Polyozellin, a major constituent of a Korea edible mushroom Polyozellus multiplex, has been known to exhibit the biological activities such as anti-oxidative and anti-inflammatory effects. Polyozellin remarkably suppressed the LPS-mediated protein expression and activity of sPLA2-IIA via inhibition of phosphorylation of cytosolic phospholipase A2 and extracellular signal-regulated kinase 1/2. These results demonstrated that polyozellin might play an important role in the modulation of sPLA2-IIA expression and activity in response to the inflammatory diseases.

  6. Sandwich enzyme-linked immunosorbent assay for detection of excretory secretory antigens in humans with fascioliasis.

    PubMed Central

    Espino, A M; Finlay, C M

    1994-01-01

    A sandwich enzyme-linked immunosorbent assay has been developed for the detection of Fasciola hepatica excretory secretory (ES) antigens in stool specimens of infected humans. The assay uses antibodies against F. hepatica ES antigens. A monoclonal antibody (ES78, mouse immunoglobulin G2a) was used to capture ES antigens, and a rabbit polyclonal antibody, peroxidase conjugate, was used to identify ES antigens. Thirteen of 14 patients with parasitological evidence of fascioliasis had a detectable concentration of ES antigens (more than 15 ng/ml). None of the stool specimens from controls and from patients with parasites other than F. hepatica showed a positive reaction, suggesting the absence of cross-reactions in this assay. When the 14 patients were retested 2 months after treatment, all of the specimens from the 11 parasitologically cured patients were negative by the antigen detection assay while the specimens from the 3 patients with persisting F. hepatica eggs in their stools remained positive. PMID:8126178

  7. Velamo do campo: its volatile constituents, secretory elements, and biological activity.

    PubMed

    El Babili, Fatiha; Roques, Christine; Haddioui, Laila; Bellvert, Floriant; Bertrand, Cédric; Chatelain, Christian

    2012-07-01

    The volatile components from Croton campestris root bark were localized by an anatomical study and analyzed by gas chromatography-mass spectrometry for the first time. The roots of this plant showed secretory cells. These volatile constituents, isolated from the dichloromethane extract by hydrodistillation, were analyzed by gas chromatography-mass spectrometry. We found 69 components. They were characterized, and the major constituents of crude oil root barks were spathulenol (23.3%) and borneol (18.7%). Growth inhibitory activity of the active compounds in solution was evaluated by measuring minimal inhibitory concentrations using a broth micromethod. The minimal inhibitory concentration of root bark volatile constituents was 1.56 μg/mL for Staphylococcus aureus, 3.125 μg/mL for Candida albicans, and 6.25 μg/mL for Aspergillusniger. PMID:22612296

  8. On psychobiology in psychoanalysis - salivary cortisol and secretory IgA as psychoanalytic process parameters

    PubMed Central

    Euler, Sebastian; Schimpf, Heinrich; Hennig, Jürgen; Brosig, Burkhard

    2005-01-01

    This study investigates the psychobiological impact of psychoanalysis in its four-hour setting. During a period of five weeks, 20 subsequent hours of psychoanalysis were evaluated, involving two patients and their analysts. Before and after each session, saliva samples were taken and analysed for cortisol (sCortisol) and secretory immunoglobuline A (sIgA). Four time-series (n=80 observations) resulted and were evaluated by "Pooled Time Series Analysis" (PTSA) for significant level changes and setting-mediated rhythms. Over all sessions, sCortisol levels were reduced and sIgA secretion augmented parallel to the analytic work. In one analytic dyad a significant rhythm within the four-hour setting was observed with an increase of sCortisol in sessions 2 and 3 of the week. Psychoanalysis may, therefore, have some psychobiological impact on patients and analysts alike and may modulate immunological and endocrinological processes. PMID:19742067

  9. Floral morphology and anatomy of Dalechampia alata Klotzsch ex Baill. (Euphorbiaceae), with emphasis on secretory structures.

    PubMed

    Martins, F M; Cunha-Neto, I L; Pereira, T M

    2016-02-01

    The morphology and anatomy of the flower of Dalechampia alata, as well as the chemical nature of the exudates secreted in the inflorescence were studied using light microscope. This is the first report showing the presence of colleters in the genus Dalechampia. In the staminate flower occur a group of small secretory glands. The histochemical results indicate that the substance secreted from the glands is lipidic and resinuous in nature, while in the colleters it consists of polysaccharides and lipid-rich substances. The ovule of D. alata are anatropous, subglobose and bitegmic. It presents obturator, micropyle occluded by nucellar beak and meristematic activity in the ovary wall. The secretion produced in the stigmatic and transmitting tissue consists of polysaccharides.

  10. Evidence for a secretory pathway Ca2+-ATPase in sea urchin spermatozoa.

    PubMed

    Gunaratne, Herath Jayantha; Vacquier, Victor D

    2006-07-10

    Plasma membrane, sarco-endoplasmic reticulum and secretory pathway Ca2+-ATPases (designated PMCA, SERCA and SPCA) regulate intracellular Ca2+ in animal cells. The presence of PMCA, and the absence of SERCA, in sea urchin sperm is known. By using inhibitors of Ca2+-ATPases, we now show the presence of SPCA and Ca2+ store in sea urchin sperm, which refills by SPCA-type pumps. Immunofluorescence shows SPCA localizes to the mitochondrion. Ca2+ measurements reveal that approximately 75% of Ca2+ extrusion is by Ca2+ ATPases and 25% by Na+ dependent Ca2+ exchanger/s. Bisphenol, a Ca2+ ATPase inhibitor, completely blocks the acrosome reaction, indicating the importance of Ca2+-ATPases in fertilization. PMID:16797550

  11. Floral morphology and anatomy of Dalechampia alata Klotzsch ex Baill. (Euphorbiaceae), with emphasis on secretory structures.

    PubMed

    Martins, F M; Cunha-Neto, I L; Pereira, T M

    2016-02-01

    The morphology and anatomy of the flower of Dalechampia alata, as well as the chemical nature of the exudates secreted in the inflorescence were studied using light microscope. This is the first report showing the presence of colleters in the genus Dalechampia. In the staminate flower occur a group of small secretory glands. The histochemical results indicate that the substance secreted from the glands is lipidic and resinuous in nature, while in the colleters it consists of polysaccharides and lipid-rich substances. The ovule of D. alata are anatropous, subglobose and bitegmic. It presents obturator, micropyle occluded by nucellar beak and meristematic activity in the ovary wall. The secretion produced in the stigmatic and transmitting tissue consists of polysaccharides. PMID:26871748

  12. Protein modifications in the plant secretory pathway: current status and practical implications in molecular pharming.

    PubMed

    Faye, Loïc; Boulaflous, Aurelia; Benchabane, Meriem; Gomord, Véronique; Michaud, Dominique

    2005-03-01

    Plants have become, over the last ten years, a suitable alternative to microbial and animal cell factories for the production of clinically-useful, therapeutic proteins. Besides the well known advantage of low-cost and large-scale production of safe and biologically active mammalian proteins, plants also are able to perform most post-translational maturations required for biological activity and suitable pharmacokinetics of recombinant therapeutic proteins. In this short review we focus on glycosylation and proteolytic processing of plant-made pharmaceuticals during their transport through the plant cell's secretory pathway. We also address the practical implications of these important processes on the effectiveness of plant molecular pharming systems. PMID:15734039

  13. Immunomodulatory effects of Trichinella spiralis-derived excretory-secretory antigens.

    PubMed

    Radovic, Ivana; Gruden-Movsesijan, Alisa; Ilic, Natasa; Cvetkovic, Jelena; Mojsilovic, Slavko; Devic, Marija; Sofronic-Milosavljevic, Ljiljana

    2015-03-01

    Helminth-derived products, either released into the circulation during the course of the infection or isolated after in vitro cultivation of the parasite and applied by the injection, are able to suppress the host immune response to autoantigens and allergens, but mechanisms could differ. Prophylactic application of Trichinella spiralis excretory-secretory muscle larvae (ES L1) products ameliorates experimental autoimmune encephalomyelitis (EAE) with the same success as infection did. However, a shift to the Th2-type response in the periphery and in the central nervous system, accompanied by activation of regulatory mechanisms, had a striking, new feature of increased proportion of unconventional CD4(+)CD25(-)Foxp3(+) regulatory cells both in the periphery and in the central nervous system of animals treated with ES L1 before the induction of EAE.

  14. Calcineurin is universally involved in vesicle endocytosis at neuronal and nonneuronal secretory cells.

    PubMed

    Wu, Xin-Sheng; Zhang, Zhen; Zhao, Wei-Dong; Wang, Dongsheng; Luo, Fujun; Wu, Ling-Gang

    2014-05-22

    Calcium influx triggers and accelerates endocytosis in nerve terminals and nonneuronal secretory cells. Whether calcium/calmodulin-activated calcineurin, which dephosphorylates endocytic proteins, mediates this process is highly controversial for different cell types, developmental stages, and endocytic forms. Using three preparations that previously produced discrepant results (i.e., large calyx-type synapses, conventional cerebellar synapses, and neuroendocrine chromaffin cells containing large dense-core vesicles), we found that calcineurin gene knockout consistently slowed down endocytosis, regardless of cell type, developmental stage, or endocytic form (rapid or slow). In contrast, calcineurin and calmodulin blockers slowed down endocytosis at a relatively small calcium influx, but did not inhibit endocytosis at a large calcium influx, resulting in false-negative results. These results suggest that calcineurin is universally involved in endocytosis. They may also help explain the discrepancies among previous pharmacological studies. We therefore suggest that calcineurin should be included as a key player in mediating calcium-triggered and -accelerated vesicle endocytosis.

  15. Myosin VI small insert isoform maintains exocytosis by tethering secretory granules to the cortical actin

    PubMed Central

    Tomatis, Vanesa M.; Papadopulos, Andreas; Malintan, Nancy T.; Martin, Sally; Wallis, Tristan; Gormal, Rachel S.; Kendrick-Jones, John; Buss, Folma

    2013-01-01

    Before undergoing neuroexocytosis, secretory granules (SGs) are mobilized and tethered to the cortical actin network by an unknown mechanism. Using an SG pull-down assay and mass spectrometry, we found that myosin VI was recruited to SGs in a Ca2+-dependent manner. Interfering with myosin VI function in PC12 cells reduced the density of SGs near the plasma membrane without affecting their biogenesis. Myosin VI knockdown selectively impaired a late phase of exocytosis, consistent with a replenishment defect. This exocytic defect was selectively rescued by expression of the myosin VI small insert (SI) isoform, which efficiently tethered SGs to the cortical actin network. These myosin VI SI–specific effects were prevented by deletion of a c-Src kinase phosphorylation DYD motif, identified in silico. Myosin VI SI thus recruits SGs to the cortical actin network, potentially via c-Src phosphorylation, thereby maintaining an active pool of SGs near the plasma membrane. PMID:23382463

  16. Selachian tooth development: II. Immunolocalization of amelogenin polypeptides in epithelium during secretory amelogenesis in Squalus acanthias.

    PubMed

    Slavkin, H C; Samuel, N; Bringas, P; Nanci, A; Santos, V

    1983-01-01

    We have determined the distribution of amelogenin polypeptides in an order of elasmobranchs using indirect immunofluorescence with rabbit polyclonal antibodies prepared to purified murine amelogenins. We find that amelogenins are definitely present within the inner enamel epithelium prior to the production of the extracellular matrix component termed "enameloid" (row II developing tooth organs). During subsequent stages of selachian tooth development (row III tooth organs), immunofluorescence staining data indicated localization of amelogenin antigens within epithelium as well as the enameloid extracellular matrix. The results from these immunohistochemical studies suggest that the 16-20 kdalton amelogenins, which are characteristic of murine inner enamel epithelial cells undergoing terminal biochemical differentiation into secretory ameloblasts, may also be regarded as molecular markers for amelogenesis in developing teeth in the spiny dogfish, Squalus acanthias.

  17. Selachian tooth development: III. Ultrastructural features of secretory amelogenesis in Squalus acanthias.

    PubMed

    Nanci, A; Bringas, P; Samuel, N; Slavkin, H C

    1983-01-01

    Ultrastructural features of secretory amelogenesis during selachian tooth development show several similarities to mammalian amelogenesis. However, the following critical differences were noticed: 1) subcellular organelles associated with merocrine-type protein synthesis and secretion were located in both the infranuclear as well as supranuclear regions of the selachian ameloblasts; 2) no evidence for Tomes process formation was found; 3) the basal lamina was not removed during epithelial differentiation into ameloblasts in the selachian model, and the structural features of the basal lamina were significantly altered during amelogenesis in rows III, IV, and VI; and 4) no dentine-enameloid junction was detected. It is suggested that enameloid is an extracellular matrix which is derived from the selachian inner enamel epithelium and appears to be secreted from both the lateral and apical surfaces of ameloblasts.

  18. Expression of Active Fluorophore Proteins in the Milk of Transgenic Pigs Bypassing the Secretory Pathway.

    PubMed

    Mukherjee, Ayan; Garrels, Wiebke; Talluri, Thirumala R; Tiedemann, Daniela; Bősze, Zsuzsanna; Ivics, Zoltán; Kues, Wilfried A

    2016-01-01

    We describe the expression of recombinant fluorescent proteins in the milk of two lines of transgenic pigs generated by Sleeping Beauty transposon-mediated genetic engineering. The Sleeping Beauty transposon consisted of an ubiquitously active CAGGS promoter driving a fluorophore cDNA, encoding either Venus or mCherry. Importantly, the fluorophore cDNAs did not encode for a signal peptide for the secretory pathway, and in previous studies of the transgenic animals a cytoplasmic localization of the fluorophore proteins was found. Unexpectedly, milk samples from lactating sows contained high levels of bioactive Venus or mCherry fluorophores. A detailed analysis suggested that exfoliated cells of the mammary epithelium carried the recombinant proteins passively into the milk. This is the first description of reporter fluorophore expression in the milk of livestock, and the findings may contribute to the development of an alternative concept for the production of bioactive recombinant proteins in the udder. PMID:27086548

  19. The local training effect of secretory activity on the response of eccrine sweat glands

    PubMed Central

    Collins, K. J.; Crockford, G. W.; Weiner, J. S.

    1966-01-01

    1. The influence of repeatedly raising the body temperature by radiant heat to a level at which acclimatization to heat is normally acquired was investigated in two series of experiments, the first without the subjects sweating, the second with sweating. 2. In a second investigation local sweat-gland activity was induced by drug injections on successive days without raising the body temperature. 3. These experiments show that the increased sweating capacity characteristic of acclimatization to heat is a result of sweat-gland activity and does not appear to be induced by or to depend on an elevated body temperature. 4. Secretory activity results in a loss of glycogen from sweat-gland cells on the first day of heat exposure but not after the glands have been `trained' by acclimatization to heat. 5. The state of acclimatization has no influence on the threshold concentration of acetylcholine required to elicit sweating when injected intradermally. PMID:5921538

  20. Non-Secretory Myeloma, Diagnosed on Renal Biopsy as Cast Nephropathy

    PubMed Central

    Selhi, Pavneet Kaur; Sood, Neena; Sandhu, Jasvinder Singh; Kaur, Harpreet

    2016-01-01

    Multiple myeloma is a disorder of plasma cells which can involve kidneys in the form of cast nephropathy. Neoplastic plasma cells produce either complete immunoglobulins or fragments of immunoglobulins leading to a monoclonal spike in the serum and/or Bence Jones proteinuria. Very few patients present as non-secretory myeloma when no immunoglobulins (M spike) are produced or only light chains are secreted which can only be detected in urine. Acute renal failure due to cast nephropathy can rarely be the first presentation of multiple myeloma. We here in report a case in which primary diagnosis of multiple myeloma was made on renal biopsy due to its characteristic histomorphology. The diagnosis was later on supported by presence of neoplastic plasma cells in the aspirate and biopsy of bone marrow. PMID:27504298

  1. On psychobiology in psychoanalysis - salivary cortisol and secretory IgA as psychoanalytic process parameters.

    PubMed

    Euler, Sebastian; Schimpf, Heinrich; Hennig, Jürgen; Brosig, Burkhard

    2005-01-01

    This study investigates the psychobiological impact of psychoanalysis in its four-hour setting. During a period of five weeks, 20 subsequent hours of psychoanalysis were evaluated, involving two patients and their analysts. Before and after each session, saliva samples were taken and analysed for cortisol (sCortisol) and secretory immunoglobuline A (sIgA). Four time-series (n=80 observations) resulted and were evaluated by "Pooled Time Series Analysis" (PTSA) for significant level changes and setting-mediated rhythms. Over all sessions, sCortisol levels were reduced and sIgA secretion augmented parallel to the analytic work. In one analytic dyad a significant rhythm within the four-hour setting was observed with an increase of sCortisol in sessions 2 and 3 of the week. Psychoanalysis may, therefore, have some psychobiological impact on patients and analysts alike and may modulate immunological and endocrinological processes.

  2. Expression of Active Fluorophore Proteins in the Milk of Transgenic Pigs Bypassing the Secretory Pathway

    PubMed Central

    Mukherjee, Ayan; Garrels, Wiebke; Talluri, Thirumala R.; Tiedemann, Daniela; Bősze, Zsuzsanna; Ivics, Zoltán; Kues, Wilfried A.

    2016-01-01

    We describe the expression of recombinant fluorescent proteins in the milk of two lines of transgenic pigs generated by Sleeping Beauty transposon-mediated genetic engineering. The Sleeping Beauty transposon consisted of an ubiquitously active CAGGS promoter driving a fluorophore cDNA, encoding either Venus or mCherry. Importantly, the fluorophore cDNAs did not encode for a signal peptide for the secretory pathway, and in previous studies of the transgenic animals a cytoplasmic localization of the fluorophore proteins was found. Unexpectedly, milk samples from lactating sows contained high levels of bioactive Venus or mCherry fluorophores. A detailed analysis suggested that exfoliated cells of the mammary epithelium carried the recombinant proteins passively into the milk. This is the first description of reporter fluorophore expression in the milk of livestock, and the findings may contribute to the development of an alternative concept for the production of bioactive recombinant proteins in the udder. PMID:27086548

  3. The role of secretory phospholipase A2 in acute chest syndrome.

    PubMed

    Kuypers, F A; Styles, L A

    2004-02-01

    Acute chest syndrome (ACS) is the leading cause of death in sickle cell disease. Severe ACS often develops in the course of a vasoocclusive crisis (VOC), and frequently involves pulmonary fat embolism. Secretory phospholipase A2 (sPLA2), a potent inflammatory mediator, is elevated in ACS, and sPLA2 levels in serum or plasma predict impending ACS. In addition sPLA2 may play a major role in the actual damage to the lung resulting in a new pulmonary infiltrate on chest radiography, respiratory symptoms, and ultimately alveolar collapse and the impairment of gas exchange. The data indicate that measurement of sPLA2 can be useful in alerting the clinician to patients with impending ACS, and suggest that instituting early therapies based on sPLA2 levels, including inhibition of sPLA2 activity, may be useful to prevent or reduce the clinical morbidity of ACS in sickle cell disease. PMID:15040432

  4. Interaction of secretory immunoglobulin A antibodies with Naegleria fowleri trophozoites and collagen type I.

    PubMed

    Shibayama, Mineko; Serrano-Luna, José de Jesús; Rojas-Hernández, Saúl; Campos-Rodríguez, Rafael; Tsutsumi, Victor

    2003-03-01

    In this work, we analyzed the in vitro interaction of human secretory immunoglobulin A (sIgA) antibodies with Naegleria fowleri trophozoites and the capacity of these antibodies to inhibit amoeba adherence to collagen type I. We also studied N. fowleri antigens that are recognized by sIgA, using immunoblot assays. Immunocytochemical analysis of the interaction showed a redistribution of antigens on the surface of trophozoites by sIgA antibodies. Ultrastructural analysis of antibody-amoeba interaction showed that besides the patching and cap formation, parasites were capable of eliminating the antigen-antibody complex produced on the surface. sIgA antibodies were capable of inhibiting the in vitro adhesion of trophozoites to collagen type I. We suggest that nonsymptomatic infections by N. fowleri may stimulate a local specific immunity that prevents trophozoite adhesion and invasion of nasal mucosa.

  5. Damascene fabrication of nonplanar microcoils

    DOEpatents

    Adams, David P.; Vasile, Michael J.

    2003-06-17

    A process for fabricating coils using a Damascene process uses a curved substrate having a surface extending along and about an axis made of a first material. A groove is formed in the curved surface along and around said axis, and the groove is filled with a second material that is different from the first material to form a coil of second material in said first material. Excess second material is then removed from the surface of the first material, leaving the coil of second material in the groove.

  6. Photolithography simulation on nonplanar substrates

    NASA Astrophysics Data System (ADS)

    Yeung, Michael S.

    1990-06-01

    A iod1 of oJ. )tica. I hthograpliy suitable for certain types of onedimensional 1)eriOdic tOpogra)hy including birds beaks afl(L reflowed BISC4 structures is described. it is based on a formalism of diffraction grating theory which uses a. coordinate t. raiisforna. tiou to iap all the nonpla. uar surfaces oiit. o parallel planes a. iid it ca. ii be used for the rigorous simulation of photoresist. latent images of oiiedimensional mask patterns with periodicity fuller j)a. ra. lleI or I)(rI)e11(Iicu1a. r to that of the topogra)hy. Effects of t. opogra)11y scattering 1)111k illiaging and )11otob1eachu1Ig are fully ta. keii into a. ccounl. for both types of mask patterns. Simulation results illustrate the combined effects of topography scattering and I) ulk iiiaging in iioiipla. na. r pliotoli tliogra. phiy using high iiuinerical aperture optics.

  7. Regulation of chloride transport in parotid secretory granules by membrane fluidity.

    PubMed

    Gasser, K W; Goldsmith, A; Hopfer, U

    1990-08-01

    Zymogen granule membranes contain Cl- conductance and Cl/anion exchange activities that become important for primary fluid production after fusion with the apical plasma membrane of the acinar cell. We have used steady-state fluorescence anisotropy of diphenylhexatriene derivatives and measurements of Cl- transport in isolated secretory granules to determine the contribution of membrane fluidity to the regulation of transport across the granule membrane. Secretory granules from several unstimulated glands (rat pancreas and parotid, rabbit gastric glands) were shown to have low membrane fluidity compared to plasma membranes. In addition, Cl- transport activity in different granule preparations showed a strong correlation to the membrane fluidity when measured with 1-[4-(trimethylammonio)phenyl]-6-phenyl-1,3,5-hexatriene p-toluenesulfonate (TMA-DPH), but not with 3-[p-(6-phenyl)-1,3,5-hexatrienyl)-phenyl]propionic acid (PA-DPH). These data suggest that TMA-DPH preferentially partitions into a specific lipid environment associated with, or which exerts an influence on, the Cl- transport proteins and that increases in the fluidity of this environment are associated with higher transport rates. Data from other types of plasma membranes indicate that TMA-DPH partitions much more than PA-DPH into the cytoplasmic leaflet, suggesting that this part of the granule membrane is involved in the observed fluidity changes. Furthermore, increasing the bulk membrane fluidity with the local anesthetics benzyl alcohol and n-alkanols increased the Cl- transport rates up to 10-fold. This increase was apparently through specific transporters as anion selectivity was maintained in spite of the higher absolute rates.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. Alteration of Bile Canalicular Enzymes in Cholestasis. A POSSIBLE CAUSE OF BILE SECRETORY FAILURE

    PubMed Central

    Simon, Francis R.; Arias, Irwin M.

    1973-01-01

    Bile secretory failure (cholestasis) may result from several possible mechanisms involved in bile secretion. We have examined the possibility that abnormalities in enzyme content, composition, and turnover of liver plasma membrane constituents are altered in cholestasis. Severe and mild cholestasis were produced by 5 days of bile duct ligation and ethinyl estradiol administration, respectively. Bile duct ligation but not ethinyl estradiol treatments was associated with elevations of the serum bilirubin level and 5′-nucleotidase activity. However, basal bile flow and bilirubin transport maximum (Tm) were significantly reduced after ethinyl estradiol treatment. Liver plasma membrane fractions rich in canalicular membranes were prepared from groups of rats in each of three categories; normal, after bile duct ligation, or ethinyl estradiol administration, and their respective controls. Electron microscopy and enzyme marker studies demonstrated plasma membrane fractions free of significant contamination. Plasma membrane fractions prepared from mild as well as severe cholestasis had increased alkaline phosphatase activity, and reduced 5′-nucleotidase and Mg2+-ATPase activities. Co2+-CMPase activity was unchanged. Kinetic analysis of 5′-nucleotidase and Mg2+-ATPase activities in plasma membrane fractions demonstrated reduced Vmaz (but unaltered Km). Reducted Vmaz was unrelated to addition in vitro of di-or trihydroxy bile salts or ethinyl estradiol and, therefore, suggests that reduced activities in cholestasis are due to decreased enzyme content. Cholestasis was not associated with changes in the synthesis or degradation rate of pulse-labeled plasma membrane proteins or alterations in the major protein bands separated on sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. Plasma membrane cholesterol, phospholipid, and neutral sugar content was unaltered, but sialic acid content was significantly increased in both forms of cholestasis. Alterations in

  9. The Spn4 gene of Drosophila encodes a potent furin-directed secretory pathway serpin

    PubMed Central

    Richer, Martin J.; Keays, Clairessa A.; Waterhouse, Jennifer; Minhas, Jessey; Hashimoto, Carl; Jean, François

    2004-01-01

    Proprotein convertases (PCs) are an important class of host-cell serine endoproteases implicated in many physiological and pathological processes. Owing to their expanding roles in the proteolytic events required for generating infectious microbial pathogens and for tumor growth and invasiveness, there is increasing interest in identifying endogenous PC inhibitors. Here we report the identification of Spn4A, a previously uncharacterized secretory pathway serine protease inhibitor (serpin) from Drosophila melanogaster that contains a consensus furin cleavage site, -ArgP4-Arg-Lys-ArgP1↓-, in its reactive site loop (RSL). Our biochemical and kinetics analysis revealed that recombinant Spn4A inhibits human furin (Ki, 13 pM; kass, 3.2 × 107 M–1·s–1) and Drosophila PC2 (Ki, 3.5 nM; kass, 9.2 × 104 M–1·s–1) by a slow-binding mechanism characteristic of serpin molecules and forms a kinetically trapped SDS-stable complex with each enzyme. For both PCs, the stoichiometry of inhibition by Spn4A is nearly 1, which is characteristic of known physiological serpin–protease interactions. Mass analysis of furin–Spn4A reaction products identified the actual reactive site center of Spn4A to be -ArgP4-Arg-Lys-ArgP1↓-. Moreover, we demonstrate that Spn4A's highly effective PC inhibition properties are critically dependent on the unusual length of its RSL, which is composed of 18 aa instead of the typical 17-residue RSL found in most other inhibitory serpins. The identification of Spn4A, the most potent and effective natural serpin of PCs identified to date, suggests that Spn4A could be a prototype of endogenous serpins involved in the precise regulation of PC-dependent proteolytic cleavage events in the secretory pathway of eukaryotic cells. PMID:15247425

  10. Persistent dominant follicle alters pattern of oviductal secretory proteins from cows at estrus.

    PubMed

    Binelli, M; Hampton, J; Buhi, W C; Thatcher, W W

    1999-07-01

    The experimental objective was to compare synthesis of oviductal secretory proteins of dairy cows bearing a persistent dominant follicle (PDF) versus a fresh dominant follicle (FDF) at estrus. On Day 7 after synchronized estrus (Day 0), cows received an intravaginal progesterone device and injection of prostaglandin F2alpha (PGF2alpha). On Day 9, cows received an injection of a GnRH agonist (FDF group; n = 3) or received no injection (PDF group, n = 3). On Day 16, all cows received PGF2alpha, and progesterone devices were removed. At slaughter on Day 18 or Day 19, oviducts ipsilateral and contralateral to the dominant follicle were divided into infundibulum, ampulla, and isthmus regions. Explants from oviductal regions were cultured in minimal essential medium supplemented with [3H]leucine for 24 h. Two-dimensional fluorographs of proteins in conditioned media were analyzed by densitometry. Rate of incorporation of [3H]leucine into macromolecules was greater in the infundibulum, ampulla, and isthmus of FDF cows (p < 0.01). Overall, intensities of radiolabeled secretory protein (P) 2 and P13 were greater for FDF than for PDF. In the ampulla, P14 was more intense for FDF while P7 was more intense for PDF. Abundance of P1 in the isthmus was greater for PDF cows. Across regions, P5, P6, P8, P9, and P11 were more intense for PDF than for FDF in the ipsilateral side. In the contralateral side, P19 was more intense for PDF than for FDF, whereas P6, P8, P9, and P11 were more intense for FDF. Differences in biosynthetic activity and in secreted oviductal proteins from cows bearing a PDF may contribute to the decrease in fertility associated with a PDF.

  11. Laboratory evolution of fast-folding green fluorescent protein using secretory pathway quality control.

    PubMed

    Fisher, Adam C; DeLisa, Matthew P

    2008-01-01

    Green fluorescent protein (GFP) has undergone a long history of optimization to become one of the most popular proteins in all of cell biology. It is thermally and chemically robust and produces a pronounced fluorescent phenotype when expressed in cells of all types. Recently, a superfolder GFP was engineered with increased resistance to denaturation and improved folding kinetics. Here we report that unlike other well-folded variants of GFP (e.g., GFPmut2), superfolder GFP was spared from elimination when targeted for secretion via the SecYEG translocase. This prompted us to hypothesize that the folding quality control inherent to this secretory pathway could be used as a platform for engineering similar 'superfolded' proteins. To test this, we targeted a combinatorial library of GFPmut2 variants to the SecYEG translocase and isolated several superfolded variants that accumulated in the cytoplasm due to their enhanced folding properties. Each of these GFP variants exhibited much faster folding kinetics than the parental GFPmut2 protein and one of these, designated superfast GFP, folded at a rate that even exceeded superfolder GFP. Remarkably, these GFP variants exhibited little to no loss in specific fluorescence activity relative to GFPmut2, suggesting that the process of superfolding can be accomplished without altering the proteins' normal function. Overall, we demonstrate that laboratory evolution combined with secretory pathway quality control enables sampling of largely unexplored amino-acid sequences for the discovery of artificial, high-performance proteins with properties that are unparalleled in their naturally occurring analogues. PMID:18545653

  12. Subcellular localization and trafficking of phytolongins (non-SNARE longins) in the plant secretory pathway

    PubMed Central

    de Marcos Lousa, Carine; Soubeyrand, Eric; Bolognese, Paolo; Wattelet-Boyer, Valerie; Bouyssou, Guillaume; Marais, Claireline; Boutté, Yohann; Filippini, Francesco; Moreau, Patrick

    2016-01-01

    SNARE proteins are central elements of the machinery involved in membrane fusion of eukaryotic cells. In animals and plants, SNAREs have diversified to sustain a variety of specific functions. In animals, R-SNARE proteins called brevins have diversified; in contrast, in plants, the R-SNARE proteins named longins have diversified. Recently, a new subfamily of four longins named ‘phytolongins’ (Phyl) was discovered. One intriguing aspect of Phyl proteins is the lack of the typical SNARE motif, which is replaced by another domain termed the ‘Phyl domain’. Phytolongins have a rather ubiquitous tissue expression in Arabidopsis but still await intracellular characterization. In this study, we found that the four phytolongins are distributed along the secretory pathway. While Phyl2.1 and Phyl2.2 are strictly located at the endoplasmic reticulum network, Phyl1.2 associates with the Golgi bodies, and Phyl1.1 locates mainly at the plasma membrane and partially in the Golgi bodies and post-Golgi compartments. Our results show that export of Phyl1.1 from the endoplasmic reticulum depends on the GTPase Sar1, the Sar1 guanine nucleotide exchange factor Sec12, and the SNAREs Sec22 and Memb11. In addition, we have identified the Y48F49 motif as being critical for the exit of Phyl1.1 from the endoplasmic reticulum. Our results provide the first characterization of the subcellular localization of the phytolongins, and we discuss their potential role in regulating the secretory pathway. PMID:26962210

  13. Myosin 2 Maintains an Open Exocytic Fusion Pore in Secretory Epithelial Cells

    PubMed Central

    Bhat, Purnima

    2009-01-01

    Many studies have implicated F-actin and myosin 2 in the control of regulated secretion. Most recently, evidence suggests a role for the microfilament network in regulating the postfusion events of vesicle dynamics. This is of potential importance as postfusion behavior can influence the loss of vesicle content and may provide a new target for drug therapy. We have investigated the role of myosin 2 in regulating exocytosis in secretory epithelial cells by using novel assays to determine the behavior of the fusion pore in individual granules. We immunolocalize myosin 2A to the apical region of pancreatic acinar cells, suggesting it is this isoform that plays a role in granule exocytosis. We further show myosin 2 phosphorylation increased on cell stimulation, consistent with a regulatory role in secretion. Importantly, in a single-cell, single-granule secretion assay, neither the myosin 2 inhibitor (−)-blebbistatin nor the myosin light chain kinase inhibitor ML-9 had any effect on the numbers of granules stimulated to fuse after cell stimulation. These data indicate that myosin 2, if it has any action on secretion, must be targeting postfusion granule behavior. This interpretation is supported by direct study of fusion pore opening in which we show that (−)-blebbistatin and ML-9 promote fusion pore closure and decrease fusion pore lifetimes. Our work now adds to a growing body of evidence showing that myosin 2 is an essential regulator of postfusion granule behavior. In particular, in the case of the secretory epithelial cells, myosin 2 activity is necessary to maintain fusion pore opening. PMID:19158378

  14. Proteomics of Secretory-Stage and Maturation-Stage Enamel of Genetically Distinct Mice.

    PubMed

    Charone, Senda; De Lima Leite, Aline; Peres-Buzalaf, Camila; Silva Fernandes, Mileni; Ferreira de Almeida, Lucas; Zardin Graeff, Marcia Sirlene; Cardoso de Oliveira, Rodrigo; Campanelli, Ana Paula; Groisman, Sonia; Whitford, Gary Milton; Everett, Eric T; Buzalaf, Marília Afonso Rabelo

    2016-01-01

    The mechanisms by which excessive ingestion of fluoride (F) during amelogenesis leads to dental fluorosis (DF) are still not precisely known. Inbred strains of mice vary in their susceptibility to develop DF, and therefore permit the investigation of underlying molecular events influencing DF severity. We employed a proteomic approach to characterize and evaluate changes in protein expression from secretory-stage and maturation-stage enamel in 2 strains of mice with different susceptibilities to DF (A/J, i.e. 'susceptible' and 129P3/J, i.e. 'resistant'). Weanling male and female susceptible and resistant mice fed a low-F diet were divided into 2 F-water treatment groups. They received water containing 0 (control) or 50 mg F/l for 6 weeks. Plasma and incisor enamel was analyzed for F content. For proteomic analysis, the enamel proteins extracted for each group were separated by 2-dimensional electrophoresis and subsequently characterized by liquid-chromatography electrospray-ionization quadrupole time-of-flight mass spectrometry. F data were analyzed by 2-way ANOVA and Bonferroni's test (p < 0.05). Resistant mice had significantly higher plasma and enamel F concentrations when compared with susceptible mice in the F-treated groups. The proteomic results for mice treated with 0 mg F/l revealed that during the secretory stage, resistant mice had a higher abundance of proteins than their susceptible counterparts, but this was reversed during the maturation stage. Treatment with F greatly increased the number of protein spots detected in both stages. Many proteins not previously described in enamel (e.g. type 1 collagen) as well as some uncharacterized proteins were identified. Our findings reveal new insights regarding amelogenesis and how genetic background and F affect this process. PMID:26820156

  15. High Expression of Water-Soluble Recombinant Antigenic Domains of Toxoplasma gondii Secretory Organelles

    PubMed Central

    Yang, Zhaoshou; Ahn, Hye-Jin

    2014-01-01

    Recombinant antigenic proteins of Toxoplasma gondii are alternative source of antigens which are easily obtainable for serodiagnosis of toxoplasmosis. In this study, highly antigenic secretory organellar proteins, dense granular GRA2 and GRA3, rhoptrial ROP2, and micronemal MIC2, were analyzed by bioinformatics approach to express as water-soluble forms of antigenic domains. The transmembrane region and disorder tendency of 4 secretory proteins were predicted to clone the genes into pGEX-4T-1 vector. Recombinant plasmids were transformed into BL21 (DE3) pLysS E. coli, and GST fusion proteins were expressed with IPTG. As a result, GST fusion proteins with GRA225-105, GRA339-138, ROP2324-561, and MIC21-284 domains had respectively higher value of IgG avidity. The rGST-GRA225-105 and rGST-GRA339-138 were soluble, while rGST-ROP2324-561 and rGST-MIC21-284 were not. GRA231-71, intrinsically unstructured domain (IUD) of GRA2, was used as a linker to enhance the solubility. The rGST-GRA231-71-ROP2324-561, a chimeric protein, appeared to be soluble. Moreover, rGST-GRA231-71-MIC21-284 was also soluble and had higher IgG avidity comparing to rGST-MIC21-284. These 4 highly expressed and water-soluble recombinant antigenic proteins may be promising candidates to improve the serodiagnosis of toxoplasmosis in addition to the major surface antigen of SAG1. PMID:25246715

  16. Monoclonal Antibodies as Probes for Unique Antigens in Secretory Cells of Mixed Exocrine Organs

    NASA Astrophysics Data System (ADS)

    Basbaum, C. B.; Mann, J. K.; Chow, A. W.; Finkbeiner, W. E.

    1984-07-01

    In the past, it has been difficult to identify the secretory product and control mechanisms associated with individual cell types making up mixed exocrine organs. This report establishes the feasibility of using immunological methods to characterize both the biochemical constituents and regulatory mechanisms associated with secretory cells in the trachea. Monoclonal antibodies directed against components of tracheal mucus were produced by immunizing mice with dialyzed, desiccated secretions harvested from tracheal organ culture. An immunofluorescence assay revealed that of the total 337 hybridomas screened, 100 produced antibodies recognizing goblet cell granules; 64, gland cell granules; and 3, antigen confined to the ciliated apical surface of the epithelium. The tracheal goblet cell antibody described in this report was strongly cross-reactive with intestinal goblet cells, as well as with a subpopulation of submandibular gland cells, but not with cells of Brunner's glands or the ciliated cell apical membrane. The serous cell antibody was not cross-reactive with goblet, Brunner's gland, or submandibular cells, or the ciliated cell apical membrane. The antibody directed against the apical membrane of ciliated cells did not cross-react with gland or goblet cells or the apical membrane of epithelial cells in the duodenum. Monoclonal antibodies, therefore, represent probes by which products unique to specific cells or parts of cells in the trachea can be distinguished. The antibodies, when used in enzyme immunoassays, can be used to quantitatively monitor secretion by individual cell types under a variety of physiological and pathological conditions. They also provide the means for purification and characterization of cell-specific products by immunoaffinity chromatography.

  17. Microarray profiling of secretory-phase endometrium from patients with recurrent miscarriage.

    PubMed

    Othman, Rosfayati; Omar, Mohd Hashim; Shan, Lim Pei; Shafiee, Mohd Nasir; Jamal, Rahman; Mokhtar, Norfilza Mohd

    2012-07-01

    The aim of the present study was to identify differentially expressed genes and their related biological pathways in the secretory phase endometrium from patients with recurrent miscarriage (RM) and fertile subjects. Endometrial samples from RM and fertile patients were analyzed using the Affymetrix GeneChip® ST Array. The bioinformatic analysis using the Partek Genomic Suite revealed 346 genes (175 up-regulated and 171 down-regulated) that were differentially expressed in the endometrium of RM patients compared to the fertile subjects (fold change ≥1.5, p<0.005). Validation step using quantitative real-time polymerase chain reaction (qPCR) confirmed a similar expression pattern of four exemplary genes: one up-regulated gene (fibroblast growth factor 9, FGF9) and three down-regulated genes: integrin β3 (ITGB3), colony stimulating factor 1 (CSF1) and matrix-metalloproteinases 19 (MMP19). The Gene Set Enrichment Analysis (GSEA) and the Pathway Studio software have found 101 signaling pathways (p<0.05) associated with the affected genes including the FGFR3 /signal transducer and activator of transcription (STAT) pathway and the CSF1R/STAT pathway. Cell adhesion, cell differentiation and angiogenesis were among biological processes indicated by this system. In conclusion, microarray technique is a useful tool to study gene expression in the secretory phase-endometrium of RM patients. The differences in endometrial gene expressions between healthy and RM subjects contribute to an increase in our knowledge on molecular mechanisms of RM development and may improve the outcome of pregnancies in high-risk women with RM.

  18. Mammaglobin and S-100 immunoreactivity in salivary gland carcinomas other than mammary analogue secretory carcinoma.

    PubMed

    Patel, Kalyani R; Solomon, Isaac H; El-Mofty, Samir K; Lewis, James S; Chernock, Rebecca D

    2013-11-01

    Mammary analogue secretory carcinoma (MASC) is a recently described salivary gland tumor that has morphologic features similar to secretory carcinoma of the breast and that also harbors the same ETV6 translocation. Diffuse mammaglobin and S-100 immunoreactivity are used to differentiate MASC from its morphologic mimics, especially acinic cell carcinoma and adenocarcinoma, not otherwise specified. However, the combination of mammaglobin and S-100 immunoreactivity has not been well studied in other types of salivary gland carcinomas that may have focal areas reminiscent of MASC. Here we evaluated mammaglobin and S-100 immunoreactivity in 15 cases each of polymorphous low-grade adenocarcinoma, adenoid cystic carcinoma and mucoepidermoid carcinoma, and also in 2 cases of adenocarcinoma, not otherwise specified, and 1 mucinous adenocarcinoma. Cases with significant co-expression of mammaglobin and S-100 (moderate or strong immunoreactivity in >25% of tumor cells) were further analyzed by fluorescence in situ hybridization using the ETV6 (12p13) break-apart probe. Nine cases (60%) of polymorphous low-grade adenocarcinoma and two (13.3%) of adenoid cystic carcinoma met the criteria for significant co-expression of mammaglobin and S-100. All were negative for the ETV6 translocation by fluorescence in situ hybridization. Although mammaglobin and S-100 positivity was seen in the majority of polymorphous low-grade adenocarcinomas and a minority of adenoid cystic carcinomas, none were positive for the ETV6 translocation characteristic of MASC. This indicates a need for caution in the use of immunohistochemistry for diagnosing MASC, especially in the absence of cytogenetic confirmation.

  19. SPRED: A machine learning approach for the identification of classical and non-classical secretory proteins in mammalian genomes

    SciTech Connect

    Kandaswamy, Krishna Kumar; Pugalenthi, Ganesan; Hartmann, Enno; Kalies, Kai-Uwe; Moeller, Steffen; Suganthan, P.N.; Martinetz, Thomas

    2010-01-15

    Eukaryotic protein secretion generally occurs via the classical secretory pathway that traverses the ER and Golgi apparatus. Secreted proteins usually contain a signal sequence with all the essential information required to target them for secretion. However, some proteins like fibroblast growth factors (FGF-1, FGF-2), interleukins (IL-1 alpha, IL-1 beta), galectins and thioredoxin are exported by an alternative pathway. This is known as leaderless or non-classical secretion and works without a signal sequence. Most computational methods for the identification of secretory proteins use the signal peptide as indicator and are therefore not able to identify substrates of non-classical secretion. In this work, we report a random forest method, SPRED, to identify secretory proteins from protein sequences irrespective of N-terminal signal peptides, thus allowing also correct classification of non-classical secretory proteins. Training was performed on a dataset containing 600 extracellular proteins and 600 cytoplasmic and/or nuclear proteins. The algorithm was tested on 180 extracellular proteins and 1380 cytoplasmic and/or nuclear proteins. We obtained 85.92% accuracy from training and 82.18% accuracy from testing. Since SPRED does not use N-terminal signals, it can detect non-classical secreted proteins by filtering those secreted proteins with an N-terminal signal by using SignalP. SPRED predicted 15 out of 19 experimentally verified non-classical secretory proteins. By scanning the entire human proteome we identified 566 protein sequences potentially undergoing non-classical secretion. The dataset and standalone version of the SPRED software is available at (http://www.inb.uni-luebeck.de/tools-demos/spred/spred).

  20. Ultrastructural patterns of secretory activity in poison cutaneous glands of larval and juvenile Dendrobates auratus (Amphibia, Anura).

    PubMed

    Angel, R; Delfino, G; Parra, G J

    2003-01-01

    A transmission electron-microscope study has been performed on larval and juvenile skin of the Central American arrow-frog Dendrobates auratus to investigate early secretory processes and maturational changes in the serous (poison) glands. Poison biosynthesis involves the endoplasmic reticulum (both smooth and rough types), as well as Golgi stacks which release early serous product as secretory vesicles (or pre-granules). These vesicles contain fine-grained material, along with single electron-opaque bodies, spheroidal in shape, that accompany the grained product throughout its post-Gogian, maturational change. The first steps of this process involve condensation and lead to the formation of secretory granules with a glomerular-like substructure, resulting from a thick, random aggregation of rods (secretory granule subunits). Advanced maturational activity causes the loss of peculiar granule substructure: the dense bodies split into fragments, whereas the thick glomerular arrangement becomes looser, until the secretory product changes into a dispersed material. This ultrastructural study revealed biosynthesis and maturation processes in close sequence, suggesting the poison of D. auratus contains proteins and/or peptides as well as lipophilic compounds. Molecules of both these classes are known to perform several roles relevant to survival strategies in extant anurans. Furthermore, the ephemeral granules with a glomerular-like substructure detected in tadpoles and froglets exhibit the complex patterns of mature poisons in adult specimens of other anurans: Hylidae and related families. This agrees with current trends in the taxonomy of these advanced frogs and underlines the pertinence of an ontogenetic approach in investigating anuran phylogenesis. PMID:12467659

  1. Protein targeting via the "constitutive-like" secretory pathway in isolated pancreatic islets: passive sorting in the immature granule compartment

    PubMed Central

    1992-01-01

    We have suggested the existence of a novel "constitutive-like" secretory pathway in pancreatic islets, which preferentially conveys a fraction of newly synthesized C-peptide, insulin, and proinsulin, and is related to the presence of immature secretory granules (IGs). Regulated exocytosis of IGs results in an equimolar secretion of C- peptide and insulin; however an assay of the constitutive-like secretory pathway recently demonstrated that this route conveys newly synthesized C-peptide in molar excess of insulin (Arvan, P., R. Kuliawat, D. Prabakaran, A.-M. Zavacki, D. Elahi, S. Wang, and D. Pilkey. J. Biol. Chem. 266:14171-14174). We now use this assay to examine the kinetics of constitutive-like secretion. Though its duration is much shorter than the life of mature granules under physiologic conditions, constitutive-like secretion appears comparatively slow (t1/2 approximately equal to 1.5 h) compared with the rate of proinsulin traffic through the ER and Golgi stacks. We have examined whether this slow rate is coupled to the rate of IG exit from the trans-Golgi network (TGN). Escape from the 20 degrees C temperature block reveals a t1/2 less than or equal to 12 min from TGN exit to stimulated release of IGs; the time required for IG formation is too rapid to be rate limiting for constitutive-like secretion. Further, conditions are described in which constitutive-like secretion is blocked yet regulated discharge of IGs remains completely intact. Thus, constitutive-like secretion appears to represent an independent secretory pathway that is kinetically restricted to a specific granule maturation period. The data support a model in which passive sorting due to insulin crystallization results in enrichment of C-peptide in membrane vesicles that bud from IGs to initiate the constitutive-like secretory pathway. PMID:1639842

  2. Three-dimensional ultrastructural analyses of anterior pituitary gland expose spatial relationships between endocrine cell secretory granule localization and capillary distribution

    PubMed Central

    Yoshitomi, Munetake; Ohta, Keisuke; Kanazawa, Tomonoshin; Togo, Akinobu; Hirashima, Shingo; Uemura, Kei-ichiro; Okayama, Satoko; Morioka, Motohiro; Nakamura, Kei-ichiro

    2016-01-01

    Endocrine and endothelial cells of the anterior pituitary gland frequently make close appositions or contacts, and the secretory granules of each endocrine cell tend to accumulate at the perivascular regions, which is generally considered to facilitate secretory functions of these cells. However, three-dimensional relationships between the localization pattern of secretory granules and blood vessels are not fully understood. To define and characterize these spatial relationships, we used scanning electron microscopy (SEM) three-dimensional reconstruction method based on focused ion-beam slicing and scanning electron microscopy (FIB/SEM). Full three-dimensional cellular architectures of the anterior pituitary tissue at ultrastructural resolution revealed that about 70% of endocrine cells were in apposition to the endothelial cells, while almost 30% of endocrine cells were entirely isolated from perivascular space in the tissue. Our three-dimensional analyses also visualized the distribution pattern of secretory granules in individual endocrine cells, showing an accumulation of secretory granules in regions in close apposition to the blood vessels in many cases. However, secretory granules in cells isolated from the perivascular region tended to distribute uniformly in the cytoplasm of these cells. These data suggest that the cellular interactions between the endocrine and endothelial cells promote an uneven cytoplasmic distribution of the secretory granules. PMID:27796315

  3. Subcellular location of secretory proteins retained in the liver during the ethanol-induced inhibition of hepatic protein secretion in the rat

    SciTech Connect

    Volentine, G.D.; Tuma, D.J.; Sorrell, M.F.

    1986-01-01

    Ethanol administration inhibits the secretion of proteins by the liver, resulting in their hepatocellular retention. Experiments were designed in this study to determine the subcellular location of the retained secretory proteins. Ethanol was administered acutely to nonfasted rats by gastric intubation, whereas control animals received an isocaloric dose of glucose. Two hours after intubation, when maximum blood ethanol levels (45 mM) were observed, (/sup 3/H)leucine and (/sup 14/C)fucose were injected simultaneously into the dorsal vein of the penis. The labelling of secretory proteins was determined in the liver and plasma at various time periods after label injection. Ethanol treatment decreased the secretion of both leucine- and fucose-labeled proteins into the plasma. This inhibition of secretion was accompanied by a corresponding increase in the hepatic retention of both leucine- and fucose-labeled immunoprecipitable secretory proteins. At the time of maximum inhibition of secretion, leucine labeled secretory proteins located in the Golgi apparatus represented about 50% of the accumulated secretory proteins in the livers of the ethanol-treated rats, whereas the remainder was essentially equally divided among the rough and smooth endoplasmic reticulum and cytosol. Because fucose is incorporated into secretory proteins almost exclusively in the Golgi complex, fucose-labeled proteins accumulated in the livers of the ethanol-treated rats mainly in the Golgi apparatus, with the remainder located in the cytosol. These results show that ethanol administration causes an impaired movement of secretory proteins along the secretory pathway, and that secretory proteins accumulate mainly, but not exclusively, in the Golgi apparatus.

  4. Active and Secretory IgA-Coated Bacterial Fractions Elucidate Dysbiosis in Clostridium difficile Infection.

    PubMed

    Džunková, Mária; Moya, Andrés; Vázquez-Castellanos, Jorge F; Artacho, Alejandro; Chen, Xinhua; Kelly, Ciaran; D'Auria, Giuseppe

    2016-01-01

    The onset of Clostridium difficile infection (CDI) has been associated with treatment with wide-spectrum antibiotics. Antibiotic treatment alters the activity of gut commensals and may result in modified patterns of immune responses to pathogens. To study these mechanisms during CDI, we separated bacteria with high cellular RNA content (the active bacteria) and their inactive counterparts by fluorescence-activated cell sorting (FACS) of the fecal bacterial suspension. The gut dysbiosis due to the antibiotic treatment may result in modification of immune recognition of intestinal bacteria. The immune recognition patterns were assessed by FACS of bacterial fractions either coated or not with intestinal secretory immunoglobulin A (SIgA). We described the taxonomic distributions of these four bacterial fractions (active versus inactive and SIgA coated versus non-SIgA coated) by massive 16S rRNA gene amplicon sequencing and quantified the proportion of C. difficile toxin genes in the samples. The overall gut microbiome composition was more robustly influenced by antibiotics than by the C. difficile toxins. Bayesian networks revealed that the C. difficile cluster was preferentially SIgA coated during CDI. In contrast, in the CDI-negative group Fusobacterium was the characteristic genus of the SIgA-opsonized fraction. Lactobacillales and Clostridium cluster IV were mostly inactive in CDI-positive patients. In conclusion, although the proportion of C. difficile in the gut is very low, it is able to initiate infection during the gut dysbiosis caused by environmental stress (antibiotic treatment) as a consequence of decreased activity of the protective bacteria. IMPORTANCE C. difficile is a major enteric pathogen with worldwide distribution. Its expansion is associated with broad-spectrum antibiotics which disturb the normal gut microbiome. In this study, the DNA sequencing of highly active bacteria and bacteria opsonized by intestinal secretory immunoglobulin A (SIg

  5. Role of calcium in secretory and metabolic effects of substrates in the gastric mucosa

    SciTech Connect

    Chacin, J.; Cardenas, P.; Lobo, P.; Subero, O.

    1986-08-01

    The role of extracellular CaS in the effects and oxidation of metabolic substrates was investigated in the isolated toad gastric mucosa. In the presence of lipoate, the stimulating effect of 10 mM glucose on spontaneous acid secretion was significantly reduced glucose on spontaneous acid secretion was significantly reduced by 76% in CaS -free solutions. The inhibition was overcome by addition of 5 mM CaS . The increment in respiration induced by glucose was also blocked in the absence of external CaS . The effect of 10 mM pyruvate on acid secretion was inhibited by 37% in CaS -free solutions. The secretory responses induced by 10 mM butyrate and 10 mM octanoate were not significantly affected by CaS -free solutions. The rates of oxidation of ( UC)-glucose and ( UC)pyruvate were significantly reduced by incubation in CaS -free solutions containing 0.1 mM of EGTA. When O2 uptake and glucose oxidation were measured simultaneously in the same preparation, the increment in the rate of glucose oxidation accounted for by 43% of the total increase of respiration observed in the presence of CaS . The rates of oxidation of ( UC)butyrate and ( UC)acetate were not significantly affected by CaS -free solutions. The rate of oxidation of ( UC)glucose exhibited saturation kinetics versus concentration and was lower in the absence of external Ca2'' under a range of glucose concentrations. Similar results were observed when the experiments were performed in the absence of external potassium to block the acid secretory process. CaS stimulated the rate of glucose oxidation in a dose-dependent manner. The kinetics of UVCaS efflux and UVCaS uptake were not significantly affected by glucose and butyrate. The results indicate that CaS is required for optimal effects of carbohydrates on secretion and metabolism in the amphibian gastric mucosa.

  6. Determination of Insulin Secretory Defect and Insulin Sensitivity in Type 2 Diabetic Subjects in Bangladesh.

    PubMed

    Ferdous, J; Ahmed, S; Laila, R; Islam, M T; Rahaman, M F; Snigdha, K R; Sarkar, S; Khan, A S; Sarkar, A K

    2016-01-01

    Diabetes mellitus (DM) is defined as a group of metabolic diseases characterized by hyperglycemia resulting from defects in insulin secretion, insulin action, or both. This study was undertaken to explore the basic defect in type 2 diabetes patients in Bangladesh. This was an observational study with case control design, was conducted in the Biomedical Research Group, Research Division, Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine Metabolic Disorders (BIRDEM), Dhaka, Bangladesh, during the period of July 2008 to June 2009. A total of 153 subjects were included in study of which 63 belonged to type 2 diabetes mellitus group and 90 were healthy controls. Fasting and 2 hours postprandial blood glucose, serum insulin, HOMA%B, HOMA%S, QuickI, Glucose /insulin ratio, TG were measured and age, BMI, WHR were recorded. Waist-hip ratio (WHR), was significantly higher in T2DM as compared to control subjects [WHR, mean±SD, 0.94±0.12 vs. 0.88±0.06, p<0.001]; Glucose and insulin ratio of T2DM was significantly higher as compared to control subject [Glu: Ins, Median (range) of 0.54 (0.17-2.33) vs. 0.37(0.06-1.52)]. Insulin secretion (HOMA%B) was significantly lower in diabetic as compared to control subjects [HOMA%B, median (range), 71(4.90-391) vs. 180(59-634) p<0.001]; The quantitative insulin sensitivity check Index (QUICKI) of diabetic subjects were significantly higher as compared to control [QUICKI median (range) 39.90(4.80-138.10) vs. 0.55(0.36-0.85), <0.001]. Triglyceride (TG) and cholesterol (Chol) were significantly higher [(mg/dl), (mean±SD), TG (142±80.14) vs. (142±80.14); Chol (189±50.76) vs. (172±45), p=0.029] in T2DM as compared to control subjects. Those with diabetes showed significant association with insulin secretory defect (HOMA%B, p=0.006) and insulin resistance as assessed by GINR (p<0.001) and QuickI (p<0.001) but not by HOMA%S (p=0.127). The present data suggest that both insulin secretory defect and insulin

  7. Active and Secretory IgA-Coated Bacterial Fractions Elucidate Dysbiosis in Clostridium difficile Infection

    PubMed Central

    Moya, Andrés; Vázquez-Castellanos, Jorge F.; Artacho, Alejandro; Chen, Xinhua; Kelly, Ciaran

    2016-01-01

    ABSTRACT The onset of Clostridium difficile infection (CDI) has been associated with treatment with wide-spectrum antibiotics. Antibiotic treatment alters the activity of gut commensals and may result in modified patterns of immune responses to pathogens. To study these mechanisms during CDI, we separated bacteria with high cellular RNA content (the active bacteria) and their inactive counterparts by fluorescence-activated cell sorting (FACS) of the fecal bacterial suspension. The gut dysbiosis due to the antibiotic treatment may result in modification of immune recognition of intestinal bacteria. The immune recognition patterns were assessed by FACS of bacterial fractions either coated or not with intestinal secretory immunoglobulin A (SIgA). We described the taxonomic distributions of these four bacterial fractions (active versus inactive and SIgA coated versus non-SIgA coated) by massive 16S rRNA gene amplicon sequencing and quantified the proportion of C. difficile toxin genes in the samples. The overall gut microbiome composition was more robustly influenced by antibiotics than by the C. difficile toxins. Bayesian networks revealed that the C. difficile cluster was preferentially SIgA coated during CDI. In contrast, in the CDI-negative group Fusobacterium was the characteristic genus of the SIgA-opsonized fraction. Lactobacillales and Clostridium cluster IV were mostly inactive in CDI-positive patients. In conclusion, although the proportion of C. difficile in the gut is very low, it is able to initiate infection during the gut dysbiosis caused by environmental stress (antibiotic treatment) as a consequence of decreased activity of the protective bacteria. IMPORTANCE C. difficile is a major enteric pathogen with worldwide distribution. Its expansion is associated with broad-spectrum antibiotics which disturb the normal gut microbiome. In this study, the DNA sequencing of highly active bacteria and bacteria opsonized by intestinal secretory immunoglobulin

  8. Involvement of various organs in the initial plasma clearance of differently glycosylated rat liver secretory proteins.

    PubMed

    Gross, V; Heinrich, P C; vom Berg, D; Steube, K; Andus, T; Tran-Thi, T A; Decker, K; Gerok, W

    1988-05-01

    The initial plasma clearance and organ distribution of alpha 1-acid glycoprotein and alpha 2-macroglobulin carrying different types of oligosaccharide, side chains was studied in rats. The differently glycosylated proteins were synthesized by rat hepatocytes in culture in the presence of tunicamycin (unglycosylated form), swainsonine (hybrid type), or 1-deoxymannojirimycin (high-mannose type). Deglycosylated glycoproteins (Asn-GlcNAc) were obtained by endoglucosaminidase H treatment of high-mannose-type glycoproteins. Ten minutes after intravenous injection 3% of complex type, 26% of hybrid type, 84% of high-mannose type. 64% of unglycosylated and 80% of deglycosylated alpha 1-acid glycoprotein disappeared from the plasma. The respective values for alpha 2-macroglobulin were 26%, 42%, 59% and 67%. When the clearance of total hepatic secretory proteins was examined, major differences between glycosylated and unglycosylated (glyco)proteins were found, particularly in the case of low-molecular-mass polypeptides. Whereas complex-type alpha 1-acid glycoprotein and alpha 2-macroglobulin showed no accumulation in various organs, hybrid-type alpha 1-acid glycoprotein and alpha 2-macroglobulin were present in spleen and liver. High-mannose-type alpha 1-acid glycoprotein and alpha 2-macroglobulin also accumulated mainly in spleen and liver. Spleen had the highest specific activity; liver, due to its larger organ mass, represented the major organ for the uptake of high-mannose-type glycoproteins. Competition experiments with mannan and GlcNAc-bovine-serum-albumin showed a mannose/GlcNAc receptor-mediated removal. Whereas unglycosylated alpha 1-acid glycoprotein was taken up by the kidney, unglycosylated alpha 2-macroglobulin was found in the spleen. Deglycosylated glycoproteins (Asn-GlcNAc) were removed from the plasma via two different mechanisms: firstly, clearance by the kidney similar to the unglycosylated glycoproteins; secondly, clearance by a mannose/GlcNAc receptor

  9. [Identification of Ca2+ release channels in salivary glands secretory cells of Chironomus plumosus L].

    PubMed

    Man'ko, V V; Bychkova, S V; Klevets', M Iu

    2004-01-01

    The presence of two types of well-characterised Ca2+ release channels, namely IP3-receptors (Ins(1,4,5)P3Rs) and ryanodine-receptors (RyRs), was detected in the salivary glands secretory cells of Chironomus plumosus L. For this aim different blockators and activators of these Ca2+ -transport systems were used. The conditions for permeabilization of these cells by saponine were experimentally chosen for their more intensive action. It was shown that IP3 decreased calcium content in saponine-treated gland tissue by (41.14 +/- 11.75)%. The effect of IP3 was not observed under condition of heparin and eosin Y presence in the incubation medium, but heparin alone did not cause any action on calcium content in saponine-treated gland tissue. The observed effects of IP3 are supposed to be the evidences of Ins (1,4,5)P3Rs presence in the intracellular membrane of this object. It was also shown that calcium content in intact gland tissue increased by (67.12 +/- 22.60)% in presence of heparin (500 mkg/ml) in the incubation medium. This effect of heparin was also observed with presence of verapamil (100 mkM) and eosin Y (5, 20 mkM) in incubation medium. So, this effect is not connected with function of voltage-gated Ca2+ -channels and Ca2+ -pumps. Ryanodine in concentration of 5nM decreased calcium content in saponine-treated gland tissue by (35.18 +/- 3.87)% but it caused the increase of calcium content at high concentration (500 nM) by (40.72 +/- 12.52)%. It improved the presence of RyRs in intracellular membrane of secretory cells of this object. Besides, these channels, perhaps, belong to "non-sensitive" to caffeine, because caffeine did not affect calcium content in the gland tissue neither in presence nor with absence of eosin Y. PMID:15909419

  10. Fine-Tuning of Electronic Structure of Cobalt(II) Ion in Nonplanar Porphyrins and Tracking of a Cross-Hybrid Stage: Implications for the Distortion of Natural Tetrapyrrole Macrocycles.

    PubMed

    Liu, Qiuhua; Zhang, Xi; Zeng, Wennan; Wang, Jianxiu; Zhou, Zaichun

    2015-11-01

    The core size of the porphyrin macrocycles was closely related to their stability of the different electron structure in the central metal ion. Cobalt(II) ions can undergo a conversion in electron configurations upon N4 core contraction of 0.05 Å in nonplanar porphyrins, and these ions still maintain low spin forms after and before conversion. The structural fine-tuning can induce the appearance of a cross-hybrid stage [d(x(2)-y(2))sp(2) ↔ d(z(2))sp(2)] based on quadrilateral coordination of the planar core. The results indicate that the configuration conversion plays a key role in electron transfer in redox catalysis involving cobalt complexes. The electronic properties of six monostrapped cobalt(II) porphyrins were investigated by spectral, paramagnetic, and electrochemical methods. The macrocyclic deformations and size parameters of Co-containing model compounds were directly obtained from their crystal structures. PMID:26461496

  11. Golgi-to-plastid trafficking of proteins through secretory pathway: Insights into vesicle-mediated import toward the plastids

    PubMed Central

    Baslam, Marouane; Oikawa, Kazusato; Kitajima-Koga, Aya; Kaneko, Kentaro; Mitsui, Toshiaki

    2016-01-01

    ABSTRACT The diversity of protein targeting pathways to plastids and their regulation in response to developmental and metabolic status is a key issue in the regulation of cellular function in plants. The general import pathways that target proteins into and across the plastid envelope with changes in gene expression are critical for plant development by regulating the response to physiological and metabolic changes within the cell. Glycoprotein targeting to complex plastids involves routing through the secretory pathway, among others. However, the mechanisms of trafficking via this system remain poorly understood. The present article discusses our results in site-specific N-glycosylation of nucleotide pyrophosphatase/phosphodiesterases (NPPs) glycoproteins and highlights protein delivery in Golgi/plastid pathway via the secretory pathway. Furthermore, we outline the hypotheses that explain the mechanism for importing vesicles trafficking with nucleus-encoded proteins into plastids. PMID:27700755

  12. The murine cytomegalovirus immunoevasin gp40 binds MHC class I molecules to retain them in the early secretory pathway.

    PubMed

    Janßen, Linda; Ramnarayan, Venkat Raman; Aboelmagd, Mohamed; Iliopoulou, Maro; Hein, Zeynep; Majoul, Irina; Fritzsche, Susanne; Halenius, Anne; Springer, Sebastian

    2016-01-01

    In the presence of the murine cytomegalovirus (mCMV) gp40 (m152) protein, murine major histocompatibility complex (MHC) class I molecules do not reach the cell surface but are retained in an early compartment of the secretory pathway. We find that gp40 does not impair the folding or high-affinity peptide binding of the class I molecules but binds to them, leading to their retention in the endoplasmic reticulum (ER), the ER-Golgi intermediate compartment (ERGIC) and the cis-Golgi, most likely by retrieval from the cis-Golgi to the ER. We identify a sequence in gp40 that is required for both its own retention in the early secretory pathway and for that of class I molecules.

  13. CCN1 contributes to skin connective tissue aging by inducing age-associated secretory phenotype in human skin dermal fibroblasts.

    PubMed

    Quan, Taihao; Qin, Zhaoping; Robichaud, Patrick; Voorhees, John J; Fisher, Gary J

    2011-08-01

    Dermal connective tissue collagen is the major structural protein in skin. Fibroblasts within the dermis are largely responsible for collagen production and turnover. We have previously reported that dermal fibroblasts, in aged human skin in vivo, express elevated levels of CCN1, and that CCN1 negatively regulates collagen homeostasis by suppressing collagen synthesis and increasing collagen degradation (Quan et al. Am J Pathol 169:482-90, 2006, J Invest Dermatol 130:1697-706, 2010). In further investigations of CCN1 actions, we find that CCN1 alters collagen homeostasis by promoting expression of specific secreted proteins, which include matrix metalloproteinases and proinflammatory cytokines. We also find that CCN1-induced secretory proteins are elevated in aged human skin in vivo. We propose that CCN1 induces an "Age-Associated Secretory Phenotype", in dermal fibroblasts, which mediates collagen reduction and fragmentation in aged human skin.

  14. Release of an acid phosphatase activity during lily pollen tube growth involves components of the secretory pathway.

    PubMed

    Ibrahim, Hala; Pertl, Heidi; Pittertschatscher, Klaus; Fadl-Allah, Ezzat; el-Shahed, Ahmed; Bentrup, Friedrich-Wilhelm; Obermeyer, Gerhard

    2002-05-01

    An acid phosphatase (acPAse) activity was released during germination and tube growth of pollen of Lilium longiflorum Thunb. By inhibiting components of the secretory pathway, the export of the acPase activity was affected and tube growth stopped. Brefeldin A (1 microM) and cytochalasin D (1 microM), which block the production and transport of secretory vesicles, respectively, inhibited the acPase secretion. The Ca2+ channel blocker gadolinium (100 microM Gd3+) also inhibited acPase secretion and tube growth, whereas 3 mM caffeine, another Ca2+ uptake inhibitor, stimulated the acPase release, while tube growth was inhibited. The Yariv reagent (beta-D-glucosyl)3 Yariv phenylglycoside stopped tube growth by binding to arabinogalactan proteins of the tube tip cell wall but did not affect acPase secretion. A strong correlation between tube growth and acPase release was detected. The secreted acPase activity had a pH optimum at pH 5.5, a KM of 0.4 mM for p-nitrophenyl phosphate, and was inhibited by zinc, molybdate, phosphate, and fluoride ions, but not by tartrate. In electrophoresis gels the main acPase activity was detected at 32 kDa. The conspicuous correlation between activity of the secretory pathway and acPase secretion during tube elongation strongly indicates an important role of the acPase during pollen tube growth and the secreted acPase activity may serve as a useful marker enzyme assay for secretory activity in pollen tubes.

  15. A role for secretory phospholipase A2 and C-reactive protein in the removal of injured cells.

    PubMed

    Hack, C E; Wolbink, G J; Schalkwijk, C; Speijer, H; Hermens, W T; van den Bosch, H

    1997-03-01

    The acute phase response is initiated in response to infection or physical trauma and is characterized by an increase in the levels of some plasma proteins. Here, Erik Hack and colleagues suggest that the combined actions of two of these acute phase proteins, secretory phospholipase A2 and C-reactive protein, may serve to promote phagocytosis of injured cells and tissue debris, thereby enhancing inflammation and tissue damage.

  16. Effects of Cichorium Intybus L. Root Extract on Secretory Activity of the Stomach in Health and Ulcer Disease.

    PubMed

    Krylova, S G; Vymyatnina, Z K; Zueva, E P; Amosova, E N; Razina, T G; Litvinenko, V I

    2015-09-01

    Gastroprotective effect of Cichorium intybus L. root extract is demonstrated on H. Shay's model of experimental ulcer in rats. The effect is attributed to the antisecretory activity of the plant and stimulation of defense barrier function of the gastric mucosa. The regulatory effect of the phytocomplex on seasonal characteristics of the gastric secretory and defense functions in dogs with Basov's fistula is detected. PMID:26468023

  17. An enzyme-linked immunosorbent assay (ELISA) for anti-chlamydial secretory immunoglobulin A in guinea pig tears.

    PubMed

    Finney, P M; Bushell, A C

    1986-01-22

    A method is described which permits the assay of specific secretory immunoglobulin A (sIgA) antibodies produced by guinea pigs in response to ocular infection with the guinea pig inclusion conjunctivitis strain of Chlamydia psittaci (GPIC agent). The enzyme-linked immunosorbent assay (ELISA) developed was shown to be more sensitive and less subjective than the micro-immunofluorescence assay as a means of assaying specific antibody.

  18. Novel Monoclonal Antibodies for Studies of Human and Rhesus Macaque Secretory Component and Human J-Chain.

    PubMed

    Zhang, Ruijun; Alam, S Munir; Yu, Jae-Sung; Scearce, Richard; Lockwood, Bradley; Hwang, Kwan-Ki; Parks, Robert; Permar, Sallie; Brandtzaeg, Per; Haynes, Barton F; Liao, Hua-Xin

    2016-08-01

    Immunoglobulin A (IgA) antibodies exist in monomeric, dimeric, and secretory forms. Dimerization of IgA depends on a 15-kD polypeptide termed "joining (J) chain," which is also part of the binding site for an epithelial glycoprotein called "secretory component (SC)," whether this after apical cleavage on secretory epithelia is ligand bound in secretory IgA (SIgA) or in a free form. Uncleaved membrane SC, also called the "polymeric Ig receptor," is thus crucial for transcytotic export of SIgA to mucosal surfaces, where it interacts with and modulates commensal bacteria and mediates protective immune responses against exogenous pathogens. To evaluate different forms of IgA, we have produced mouse monoclonal antibodies (MAbs) against human J-chain and free SC. We found that J-chain MAb 9A8 and SC MAb 9H7 identified human dimeric IgA and SIgA in enzyme-linked immunoassay and western blot analysis, as well as functioning in immunohistochemistry to identify cytoplasmic IgA of intestinal lamina propria plasmablasts/plasma cells and crypt epithelium of distal human intestine. Finally, we demonstrated that SC MAb 9H7 cross-reacted with rhesus macaque SIgA. These novel reagents should be of use in the study of the biology of various forms of IgA in humans and SIgA in macaques, as well as in monitoring the production and/or isolation of these forms of IgA. PMID:27386924

  19. Enhanced cell-surface display and secretory production of cellulolytic enzymes with Saccharomyces cerevisiae Sed1 signal peptide.

    PubMed

    Inokuma, Kentaro; Bamba, Takahiro; Ishii, Jun; Ito, Yoichiro; Hasunuma, Tomohisa; Kondo, Akihiko

    2016-11-01

    Recombinant yeast strains displaying aheterologous cellulolytic enzymes on their cell surfaces using a glycosylphosphatidylinositol (GPI) anchoring system are a promising strategy for bioethanol production from lignocellulosic materials. A crucial step for cell wall localization of the enzymes is the intracellular transport of proteins in yeast cells. Therefore, the addition of a highly efficient secretion signal sequence is important to increase the amount of the enzymes on the yeast cell surface. In this study, we demonstrated the effectiveness of a novel signal peptide (SP) sequence derived from the Saccharomyces cerevisiae SED1 gene for cell-surface display and secretory production of cellulolytic enzymes. Gene cassettes with SP sequences derived from S. cerevisiae SED1 (SED1SP), Rhizopus oryzae glucoamylase (GLUASP), and S. cerevisiae α-mating pheromone (MFα1SP) were constructed for cell-surface display of Aspergillus aculeatus β-glucosidase (BGL1) and Trichoderma reesei endoglucanase II (EGII). These gene cassettes were integrated into the S. cerevisiae genome. The recombinant strains with the SED1SP showed higher cell-surface BGL and EG activities than those with the conventional SP sequences (GLUASP and MFα1SP). The novel SP sequence also improved the secretory production of BGL and EG in S. cerevisiae. The extracellular BGL activity of the recombinant strains with the SED1SP was 1.3- and 1.9-fold higher than the GLUASP and MFα1SP strains, respectively. Moreover, the utilization of SED1SP successfully enhanced the secretory production of BGL in Pichia pastoris. The utilization of the novel SP sequence is a promising option for highly efficient cell-surface display and secretory production of heterologous proteins in various yeast species. Biotechnol. Bioeng. 2016;113: 2358-2366. © 2016 Wiley Periodicals, Inc. PMID:27183011

  20. Inhibition of intestinal chloride secretion by piperine as a cellular basis for the anti-secretory effect of black peppers.

    PubMed

    Pongkorpsakol, Pawin; Wongkrasant, Preedajit; Kumpun, Saowanee; Chatsudthipong, Varanuj; Muanprasat, Chatchai

    2015-10-01

    Piperine is the principal alkaloid in black peppers (Piper nigrum L.), which is a commonly included spice in anti-diarrheal formulations. Piperine has antispasmodic activities, but its anti-secretory effect is not known. Therefore, this study investigated the anti-secretory effect of piperine and its underlying mechanism. Piperine inhibited cAMP-mediated Cl- secretion in human intestinal epithelial (T84) cells, similar to black pepper extract. Intraluminal administration of piperine (2 μg/loop) suppressed cholera toxin-induced intestinal fluid accumulation by ∼85% in mice. The anti-secretory mechanism of piperine was investigated by evaluating its effects on the activity of transport proteins involved in cAMP-mediated Cl- secretion. Notably, piperine inhibited CFTR Cl- channel activity (IC50#8'6#10 μM) without affecting intracellular cAMP levels. The mechanisms of piperine-induced CFTR inhibition did not involve MRP4-mediated cAMP efflux, AMPK or TRPV1. Piperine also inhibited cAMP-activated basolateral K+ channels, but it had no effect on Na+-K+-Cl- cotransporters or Na+-K+ ATPases. Piperine suppressed Ca2+-activated Cl- channels (CaCC) without affecting intracellular Ca2+ concentrations or Ca2+-activated basolateral K+ channels. Collectively, this study indicates that the anti-secretory effect of piperine involves the inhibition of CFTR, CaCC and cAMP-activated basolateral K+ channels. Piperine represents a novel class of drug candidates for the treatment of diarrheal diseases caused by the intestinal hypersecretion of Cl-. PMID:26297981

  1. Inhibition of intestinal chloride secretion by piperine as a cellular basis for the anti-secretory effect of black peppers.

    PubMed

    Pongkorpsakol, Pawin; Wongkrasant, Preedajit; Kumpun, Saowanee; Chatsudthipong, Varanuj; Muanprasat, Chatchai

    2015-10-01

    Piperine is the principal alkaloid in black peppers (Piper nigrum L.), which is a commonly included spice in anti-diarrheal formulations. Piperine has antispasmodic activities, but its anti-secretory effect is not known. Therefore, this study investigated the anti-secretory effect of piperine and its underlying mechanism. Piperine inhibited cAMP-mediated Cl- secretion in human intestinal epithelial (T84) cells, similar to black pepper extract. Intraluminal administration of piperine (2 μg/loop) suppressed cholera toxin-induced intestinal fluid accumulation by ∼85% in mice. The anti-secretory mechanism of piperine was investigated by evaluating its effects on the activity of transport proteins involved in cAMP-mediated Cl- secretion. Notably, piperine inhibited CFTR Cl- channel activity (IC50#8'6#10 μM) without affecting intracellular cAMP levels. The mechanisms of piperine-induced CFTR inhibition did not involve MRP4-mediated cAMP efflux, AMPK or TRPV1. Piperine also inhibited cAMP-activated basolateral K+ channels, but it had no effect on Na+-K+-Cl- cotransporters or Na+-K+ ATPases. Piperine suppressed Ca2+-activated Cl- channels (CaCC) without affecting intracellular Ca2+ concentrations or Ca2+-activated basolateral K+ channels. Collectively, this study indicates that the anti-secretory effect of piperine involves the inhibition of CFTR, CaCC and cAMP-activated basolateral K+ channels. Piperine represents a novel class of drug candidates for the treatment of diarrheal diseases caused by the intestinal hypersecretion of Cl-.

  2. Fecal secretory immunoglobulin A in breast milk versus formula feeding in early infancy.

    PubMed

    Koutras, A K; Vigorita, V J

    1989-07-01

    We studied the effects of breast milk feeding versus formula feeding during the first 8 weeks of life on the development of local gastrointestinal humoral immune response by measuring fecal secretory immunoglobulin A (SIgA). Forty-four infants were studied and classified into two groups: breast milk (n = 21) and standard Enfamil without iron (n = 23). The fecal specimens were analyzed at birth and 2, 4, and 8 weeks of age. Radial immune diffusion (RID) technique was used to assay the fecal SIgA during these four ages. Marked SIgA changes were detected in the breast milk-fed group. At birth, no fecal SIgA was detected in either group. At 2, 4, and 8 weeks, significant differences were found between the two groups (p4 less than or equal to 0.001 and p8 less than or equal to 0.001). This phenomenon of enhanced fecal SIgA in breast-fed infants versus standard formula-fed infants is not caused solely by the presence of IgA in breast milk; it represents a stimulatory effect of breast milk on the gastrointestinal humoral immunologic development. The possible active stimulatory role of breast milk on the development of immunologic competence and host defense is discussed. These data suggest an additional advantage of breast milk feeding during early life by the protective role of the earlier and enhanced production of SIgA in the gastrointestinal tract.

  3. M. tuberculosis Secretory Protein ESAT-6 Induces Metabolic Flux Perturbations to Drive Foamy Macrophage Differentiation.

    PubMed

    Singh, Varshneya; Kaur, Charanpreet; Chaudhary, Vijay K; Rao, Kanury V S; Chatterjee, Samrat

    2015-01-01

    The Foamy Macrophage (FM) differentiation forms a major component of the host dependent survival axis of M. tuberculosis. The FM which are characterized by the intracellular accumulation of lipid bodies (LBs), ensure a privileged existence for the bacilli through ready provision of nutrients and by conferring protection against bactericidal pathways. The mycobacterial secretory protein ESAT-6 has been identified as the molecular mediator of the FM differentiation process although little is known about the mechanism through which it induces this process. In the present study, we show that ESAT-6 induces GLUT-1 mediated enhanced glucose uptake by macrophages which is coupled to metabolic flux perturbations in the glycolytic pathway caused by differential rates of reaction at several steps in the pathway. Two major changes identified were the simultaneous buildup of DHAP (for Triglyceride synthesis) and AcCoA (for synthesis of 3-HB, ligand for the anti-lipolytic GPR109A). We also show that part of the observed effects involve protein- protein interactions between ESAT-6 and the macrophage glycolytic enzymes, Enolase1 and Phosphoglycerate kinase1. PMID:26250836

  4. Improving the Secretory Expression of an -Galactosidase from Aspergillus niger in Pichia pastoris.

    PubMed

    Zheng, Xianliang; Fang, Bo; Han, Dongfei; Yang, Wenxia; Qi, Feifei; Chen, Hui; Li, Shengying

    2016-01-01

    α-Galactosidases are broadly used in feed, food, chemical, pulp, and pharmaceutical industries. However, there lacks a satisfactory microbial cell factory that is able to produce α-galactosidases efficiently and cost-effectively to date, which prevents these important enzymes from greater application. In this study, the secretory expression of an Aspergillus niger α-galactosidase (AGA) in Pichia pastoris was systematically investigated. Through codon optimization, signal peptide replacement, comparative selection of host strain, and saturation mutagenesis of the P1' residue of Kex2 protease cleavage site for efficient signal peptide removal, a mutant P. pastoris KM71H (Muts) strain of AGA-I with the specific P1' site substitution (Glu to Ile) demonstrated remarkable extracellular α-galactosidase activity of 1299 U/ml upon a 72 h methanol induction in 2.0 L fermenter. The engineered yeast strain AGA-I demonstrated approximately 12-fold higher extracellular activity compared to the initial P. pastoris strain. To the best of our knowledge, this represents the highest yield and productivity of a secreted α-galactosidase in P. pastoris, thus holding great potential for industrial application. PMID:27548309

  5. Relationship of the quaternary structure of human secretory IgA to neutralization of influenza virus.

    PubMed

    Suzuki, Tadaki; Kawaguchi, Akira; Ainai, Akira; Tamura, Shin-ichi; Ito, Ryo; Multihartina, Pretty; Setiawaty, Vivi; Pangesti, Krisna Nur Andriana; Odagiri, Takato; Tashiro, Masato; Hasegawa, Hideki

    2015-06-23

    Secretory IgA (S-IgA) antibodies, the major contributors to humoral mucosal immunity to influenza virus infection, are polymeric Igs present in many external secretions. In the present study, the quaternary structures of human S-IgA induced in nasal mucosa after administration of intranasal inactivated influenza vaccines were characterized in relation to neutralization potency against influenza A viruses. Human nasal IgA antibodies have been shown to contain at least five quaternary structures. Direct and real-time visualization of S-IgA using high-speed atomic force microscopy (AFM) demonstrated that trimeric and tetrameric S-IgA had six and eight antigen-binding sites, respectively, and that these structures exhibited large-scale asynchronous conformational changes while capturing influenza HA antigens in solution. Furthermore, trimeric, tetrameric, and larger polymeric structures, which are minor fractions in human nasal IgA, displayed increased neutralizing potency against influenza A viruses compared with dimeric S-IgA, suggesting that the larger polymeric than dimeric forms of S-IgA play some important roles in protection against influenza A virus infection in the human upper respiratory tract.

  6. OKT3-induced nephrotoxicity is associated with release of group II secretory phospholipase A2.

    PubMed

    Wever, P C; Roest, R W; Wolbink-Kamp, A M; Wolbink, G J; Weening, J J; Hack, C E; ten Berge, J M

    1996-10-01

    Administration of the murine IgG2a CD3 monoclonal antibody OKT3 exerts a transient nephrotoxic effect. Increased levels of group II secretory phospholipase A2 (sPLA2-II) might account for this nephrotoxicity as sPLA2-II induces the biosynthesis of prostaglandins, vasoactive lipid mediators that influence glomerular haemodynamics and renal function. Furthermore, extracellular phospholipases seem to be involved in proximal tubular cell injury. We studied plasma sPLA2-II levels in relation to circulating creatinine, tumour necrosis factor alpha, interleukin 6 and C-reactive protein levels in 15 renal allograft recipients receiving rejection treatment with OKT3. As a control group, we studied 15 renal allograft recipients receiving rejection treatment with methylprednisolone. A maximal fourfold increase in sPLA2-II levels was observed 48 h after the first OKT3 administration, preceded by increased tumour necrosis factor alpha and interleukin 6 levels and accompanied by increased C-reactive protein levels. Creatinine levels reached a maximal increase 72 h after initiation of treatment. During methylprednisolone treatment no increase in any of the studied parameters was observed. Thus, administration of OKT3 induces increased sPLA2-II levels, presumably via generation of cytokines. We hypothesize that sPLA2-II may contribute to the nephrotoxic effect of OKT3 by inducing vasoconstrictive prostaglandins and renal tubular cell injury.

  7. Weight Loss Improves the Adipogenic Capacity of Human Preadipocytes and Modulates Their Secretory Profile

    PubMed Central

    Rossmeislová, Lenka; Mališová, Lucia; Kračmerová, Jana; Tencerová, Michaela; Kováčová, Zuzana; Koc, Michal; Šiklová-Vítková, Michaela; Viquerie, Nathalie; Langin, Dominique; Štich, Vladimír

    2013-01-01

    Calorie restriction–induced weight loss is accompanied by profound changes in adipose tissue characteristics. To determine the effect of weight loss on differentiation of preadipocytes and secretory capacity of in vitro differentiated adipocytes, we established cultures of these cells from paired subcutaneous adipose tissue biopsies obtained before and at the end of weight-reducing dietary intervention (DI) in 23 obese women. Based on lipid accumulation and the expression of differentiation markers, in vitro adipogenesis increased after weight loss and it was accompanied by enhanced expression of genes involved in de novo lipogenesis. This effect of weight loss was not driven by changes of peroxisome proliferator–activated receptor γ sensitivity to rosiglitazone. Weight loss also enhanced the expression of adiponectin and leptin while reducing that of monocyte chemoattractant protein 1 and interleukin-8 by cultured adipocytes. Thus, the weight-reducing (DI) increased adipogenic capacity of preadipocytes and shifted their secretion toward lower inflammatory profile. Reprogramming of preadipocytes could represent an adaptation to weight loss leading to partial restoration of preobese adipose tissue traits and thus contribute to the improvement of metabolic status. However, enhanced adipogenesis could also contribute to the unwanted weight regain after initial weight loss. PMID:23378611

  8. Production of Secretory and Extracellular N-Linked Glycoproteins in Escherichia coli▿ †

    PubMed Central

    Fisher, Adam C.; Haitjema, Charles H.; Guarino, Cassandra; Çelik, Eda; Endicott, Christine E.; Reading, Craig A.; Merritt, Judith H.; Ptak, A. Celeste; Zhang, Sheng; DeLisa, Matthew P.

    2011-01-01

    The Campylobacter jejuni pgl gene cluster encodes a complete N-linked protein glycosylation pathway that can be functionally transferred into Escherichia coli. In this system, we analyzed the interplay between N-linked glycosylation, membrane translocation and folding of acceptor proteins in bacteria. We developed a recombinant N-glycan acceptor peptide tag that permits N-linked glycosylation of diverse recombinant proteins expressed in the periplasm of glycosylation-competent E. coli cells. With this “glycosylation tag,” a clear difference was observed in the glycosylation patterns found on periplasmic proteins depending on their mode of inner membrane translocation (i.e., Sec, signal recognition particle [SRP], or twin-arginine translocation [Tat] export), indicating that the mode of protein export can influence N-glycosylation efficiency. We also established that engineered substrate proteins targeted to environments beyond the periplasm, such as the outer membrane, the membrane vesicles, and the extracellular medium, could serve as substrates for N-linked glycosylation. Taken together, our results demonstrate that the C. jejuni N-glycosylation machinery is compatible with distinct secretory mechanisms in E. coli, effectively expanding the N-linked glycome of recombinant E. coli. Moreover, this simple glycosylation tag strategy expands the glycoengineering toolbox and opens the door to bacterial synthesis of a wide array of recombinant glycoprotein conjugates. PMID:21131519

  9. Function of Secretory Leukocyte Protease Inhibitor (SLPI) in Odontoblast During Mouse Tooth Development.

    PubMed

    Jeong, Je-O; Wang, Guanlin; Jeong, Soon-Jeong; Choi, Baik-Dong; Lee, Hye-Yon; Jeong, Moon-Jin

    2015-01-01

    Secretory leuckocyte protease inhibitor (SLPI) is thought as a regulating protein on the synthesis and degradation of matrix proteins. But there was no report of expression and function of SLPI on the tooth development, especially on the odontoblasts. As observed by in-situ hybridization and immunohistochemical analysis, SLPI was expressed in odontoblasts and predentin on post-natal day 4 (PN4). On PN10, SLPI was observed under the dentin and apical region including odontoblasts processes. Further, on PN15, expression of SLPI was the same pattern compared to PN10. SLPI was expressed under layer of the odontoblasts and in odontoblasts on PN20. Matrix metalloproteinase-2 (MMP-2) and -9 levels in SLPI/MDPC-23 cells were higher than that of the MDPC-23 cells. The gene expression of SLPI, bone sialoprotein (BSP), osteocalcin (OCN), osteonectin (ON), and collagen type I (Col I) was higher in SLPI/MDPC-23 than that of MDPC-23 cells and the expression of dentin sialophosphoprotein (DSPP) was lower in SLPI/MDPC-23. Taken together, our results suggest that SLPI may be a MMP-2 and -9 regulating molecule in odontoblasts during dentin matrix formation and acts as a signaling molecule for dentin matrix related proteins during odontoblasts differentiation and mineralization.

  10. In vivo induction of neutrophil chemotaxis by secretory aspartyl proteinases of Candida albicans.

    PubMed

    Gabrielli, Elena; Sabbatini, Samuele; Roselletti, Elena; Kasper, Lydia; Perito, Stefano; Hube, Bernhard; Cassone, Antonio; Vecchiarelli, Anna; Pericolini, Eva

    2016-10-01

    Secretory aspartyl proteinases (Saps) of Candida albicans are key virulence traits which cause inflammasome-dependent, aseptic inflammation in a mouse model of vaginitis. In this paper, neutrophil migration in response to Sap2, Sap6 and chemo-attractive products released from Sap-treated vaginal epithelium was measured in vitro, ex vivo and in vivo. Our results show that Sap2 and Sap6 induce neutrophil migration and production of potent chemoattractive chemokines such as IL-8 and MIP-2 by vaginal epithelial cells. Our data suggest that at least part of MIP-2 production depends upon IL-1β activity. The vaginal fluid of Candida-infected mice contained a heat-labile inhibitor of neutrophil candidacidal activity that was absent from the vaginal fluid of Sap-treated mice. Overall, our data provide additional information on the capacity of C. albicans Saps to cause aseptic vaginal inflammation and highlight the potential role of some chemokines released from vaginal epithelial cells in this phenomenon.

  11. Stichopin-containing nerves and secretory cells specific to connective tissues of the sea cucumber.

    PubMed

    Tamori, Masaki; Saha, Apurba Kumar; Matsuno, Akira; Noskor, Sukumar Chandra; Koizumi, Osamu; Kobayakawa, Yoshitaka; Nakajima, Yoko; Motokawa, Tatsuo

    2007-09-22

    Stichopin, a 17-amino acid peptide isolated from a sea cucumber, affects the stiffness change of the body-wall catch connective tissues and the contraction of the body-wall muscles. The localization of stichopin in sea cucumbers was studied by indirect immunohistochemistry using antiserum against stichopin. Double staining was performed with both stichopin antiserum and 1E11, the monoclonal antibody specific to echinoderm nerves. A stichopin-like immunoreactivity (stichopin-LI) was exclusively found in the connective tissues of various organs. Many fibres and cells with processes were stained by both the anti-stichopin antibody and 1E11. They were found in the body-wall dermis and the connective tissue layer of the cloacae and were suggested to be connective tissue-specific nerves. Oval cells with stichopin-LI (OCS) without processes were found in the body-wall dermis, the connective tissue sheath of the longitudinal body-wall muscles, the connective tissue layer of the tube feet and tentacles, and the connective tissue in the radial nerves separating the ectoneural part from the hyponeural part. Electron microscopic observations of the OCSs in the radial nerves showed that they were secretory cells. The OCSs were located either near the well-defined neural structures or near the water-filled cavities, such as the epineural sinus and the canals of the tube feet. The location near the water-filled cavities might suggest that stichopin was secreted into these cavities to function as a hormone.

  12. Nanosilver pathophysiology in earthworms: Transcriptional profiling of secretory proteins and the implication for the protein corona.

    PubMed

    Hayashi, Yuya; Miclaus, Teodora; Engelmann, Péter; Autrup, Herman; Sutherland, Duncan S; Scott-Fordsmand, Janeck J

    2016-01-01

    Previously we have identified lysenin as a key protein constituent of the secretome from Eisenia fetida coelomocytes and revealed its critical importance in priming interactions between the cells and the protein corona around nanosilver. As alterations of the protein environment can directly affect the corona composition, the extent to which nanoparticles influence the cells' protein secretion profile is of remarkable interest that has rarely acquired attention. Here, we have probed transcriptional responses of E. fetida coelomocytes to the representative nanosilver NM-300K (15 nm) in a time-dependent manner (2, 4, 8 and 24 h at a low-cytotoxic concentration), and examined the implication of the temporal changes in transcriptional profiles of secretory proteins with a particular reference to that of lysenin. NM-300K was accumulated in/at the cells and lysenin was, after transient induction, gradually suppressed over time indicating a negative feedback cycle. This may limit further enrichment of lysenin in the corona and thereby decrease the lysenin-assisted uptake of the nanoparticles. Other differentially expressed genes were those involved in metal stress (likewise in AgNO3-stressed cells) and in Toll-like receptor (TLR) signaling. This offers an intriguing perspective of the nanosilver pathophysiology in earthworms, in which the conserved pattern recognition receptor TLRs may play an effector role.

  13. Molecular mechanisms involved in secretory vesicle recruitment to the plasma membrane in beta-cells.

    PubMed

    Varadi, Aniko; Ainscow, E K; Allan, V J; Rutter, G A

    2002-04-01

    Glucose stimulates the release of insulin in part by activating the recruitment of secretory vesicles to the cell surface. While this movement is known to be microtubule-dependent, the molecular motors involved are undefined. Active kinesin was found to be essential for vesicle translocation in live beta-cells, since microinjection of cDNA encoding dominant-negative KHC(mut) (motor domain of kinesin heavy chain containing a Thr(93)-->Asn point mutation) blocked vesicular movements. Moreover, expression of KHC(mut) strongly inhibited the sustained, but not acute, stimulation of secretion by glucose. Thus, vesicles released during the first phase of insulin secretion exist largely within a translocation-independent pool. Kinesin-driven anterograde movement of vesicles is then necessary for the sustained (second phase) of insulin release. Kinesin may, therefore, represent a novel target for increases in intracellular ATP concentrations in response to elevated extracellular glucose and may be involved in the ATP-sensitive K+channel-independent stimulation of secretion by the sugar.

  14. Multi-Faceted Functions of Secretory IgA at Mucosal Surfaces

    PubMed Central

    Corthésy, Blaise

    2013-01-01

    Secretory IgA (SIgA) plays an important role in the protection and homeostatic regulation of intestinal, respiratory, and urogenital mucosal epithelia separating the outside environment from the inside of the body. This primary function of SIgA is referred to as immune exclusion, a process that limits the access of numerous microorganisms and mucosal antigens to these thin and vulnerable mucosal barriers. SIgA has been shown to be involved in avoiding opportunistic pathogens to enter and disseminate in the systemic compartment, as well as tightly controlling the necessary symbiotic relationship existing between commensals and the host. Clearance by peristalsis appears thus as one of the numerous mechanisms whereby SIgA fulfills its function at mucosal surfaces. Sampling of antigen-SIgA complexes by microfold (M) cells, intimate contact occurring with Peyer’s patch dendritic cells (DC), down-regulation of inflammatory processes, modulation of epithelial, and DC responsiveness are some of the recently identified processes to which the contribution of SIgA has been underscored. This review aims at presenting, with emphasis at the biochemical level, how the molecular complexity of SIgA can serve these multiple and non-redundant modes of action. PMID:23874333

  15. Xbp1-based engineering of secretory capacity enhances the productivity of Chinese hamster ovary cells.

    PubMed

    Tigges, Marcel; Fussenegger, Martin

    2006-05-01

    A variety of successful transcription and translation engineering strategies implemented during the past decade have driven the specific productivity of mammalian cells to an apparent limit. Restricted post-translation competence has since been considered the major bottleneck preventing mammalian cells from fully exploiting their physiologic production capacity in a biopharmaceutical manufacturing scenario. Through ectopic expression of the human transcription factor Xbp1 (X-box-binding-protein 1), evolved to manage plasma cell differentiation and coordinate the unfolded protein response, we have specifically expanded the endoplasmic reticulum and the Golgi of transgenic Chinese hamster ovary (CHO-K1)-derived cell lines with a resulting increase in overall production capacity. Xbp-1-based engineering of secretory bottlenecks was compatible with a variety of different promoter–product gene configurations suggesting that Xbp-1 induces generic production increases in CHO-K1 cell derivatives. Secretion engineering, illustrated here by Xbp1-based reprogramming of the post-translational processing machinery, provides a first insight into mastering a major system bottleneck which impacts biopharmaceutical manufacturing of secreted protein therapeutics.

  16. Altered synthesis of some secretory proteins in pancreatic lobules isolated from streptozotocin-induced diabetic rats

    SciTech Connect

    Duan, R.D.; Erlanson-Albertsson, C. )

    1990-03-01

    The in vitro incorporation of (35S)cysteine into lipase, colipase, amylase, procarboxypeptidase A and B, and the serine proteases and total proteins was studied in pancreatic lobules isolated from normal and diabetic rats with or without insulin treatment. The incorporation of (35S)cysteine into total proteins was 65% greater in pancreatic lobules from diabetic animals than from normal rats. The increased incorporation was partly reversed by insulin treatment (2 U/100 g/day for 5 days) of diabetic rats. The relative rates of biosynthesis for amylase and the procarboxypeptidases in diabetic pancreatic lobules were decreased by 75 and 25%, respectively, after 1 h of incubation, while those for lipase, colipase, and the serine proteases were increased by 90, 85, and 35%, respectively. The absolute rates of synthesis for these enzymes changed in the same direction as the relative rates in diabetic lobules, except that for the procarboxypeptidases, which did not change. The changed rates of biosynthesis for the pancreatic enzymes were reversed by insulin treatment of the diabetic rats. Kinetic studies showed that the incorporation of (35S)cysteine into amylase, lipase, and colipase was linear until up to 2 h of incubation in normal pancreatic lobules, while in the diabetic lobules the incorporation into lipase and colipase was accelerated, reaching a plateau level already after 1 h of incubation. It is concluded that the biosynthesis of pancreatic secretory proteins in diabetic rats is greatly changed both in terms of quantity and kinetics.

  17. Mast cell mediators: their differential release and the secretory pathways involved.

    PubMed

    Moon, Tae Chul; Befus, A Dean; Kulka, Marianna

    2014-01-01

    Mast cells (MC) are widely distributed throughout the body and are common at mucosal surfaces, a major host-environment interface. MC are functionally and phenotypically heterogeneous depending on the microenvironment in which they mature. Although MC have been classically viewed as effector cells of IgE-mediated allergic diseases, they are also recognized as important in host defense, innate and acquired immunity, homeostatic responses, and immunoregulation. MC activation can induce release of pre-formed mediators such as histamine from their granules, as well as release of de novo synthesized lipid mediators, cytokines, and chemokines that play diverse roles, not only in allergic reactions but also in numerous physiological and pathophysiological responses. Indeed, MC release their mediators in a discriminating and chronological manner, depending upon the stimuli involved and their signaling cascades (e.g., IgE-mediated or Toll-like receptor-mediated). However, the precise mechanisms underlying differential mediator release in response to these stimuli are poorly known. This review summarizes our knowledge of MC mediators and will focus on what is known about the discriminatory release of these mediators dependent upon diverse stimuli, MC phenotypes, and species of origin, as well as on the intracellular synthesis, storage, and secretory processes involved.

  18. Mast Cell Mediators: Their Differential Release and the Secretory Pathways Involved

    PubMed Central

    Moon, Tae Chul; Befus, A. Dean; Kulka, Marianna

    2014-01-01

    Mast cells (MC) are widely distributed throughout the body and are common at mucosal surfaces, a major host–environment interface. MC are functionally and phenotypically heterogeneous depending on the microenvironment in which they mature. Although MC have been classically viewed as effector cells of IgE-mediated allergic diseases, they are also recognized as important in host defense, innate and acquired immunity, homeostatic responses, and immunoregulation. MC activation can induce release of pre-formed mediators such as histamine from their granules, as well as release of de novo synthesized lipid mediators, cytokines, and chemokines that play diverse roles, not only in allergic reactions but also in numerous physiological and pathophysiological responses. Indeed, MC release their mediators in a discriminating and chronological manner, depending upon the stimuli involved and their signaling cascades (e.g., IgE-mediated or Toll-like receptor-mediated). However, the precise mechanisms underlying differential mediator release in response to these stimuli are poorly known. This review summarizes our knowledge of MC mediators and will focus on what is known about the discriminatory release of these mediators dependent upon diverse stimuli, MC phenotypes, and species of origin, as well as on the intracellular synthesis, storage, and secretory processes involved. PMID:25452755

  19. Structure and Switch Cycle of SRβ as Ancestral Eukaryotic GTPase Associated with Secretory Membranes.

    PubMed

    Jadhav, Bhalchandra; Wild, Klemens; Pool, Martin R; Sinning, Irmgard

    2015-10-01

    G proteins of the Ras-family of small GTPases trace the evolution of eukaryotes. The earliest branching involves the closely related Arf, Sar1, and SRβ GTPases associated with secretory membranes. SRβ is an integral membrane component of the signal recognition particle (SRP) receptor that targets ribosome-nascent chain complexes to the ER. How SRβ integrates into the regulation of SRP-dependent membrane protein biogenesis is not known. Here we show that SRβ-GTP interacts with ribosomes only in presence of SRα and present crystal structures of SRβ in complex with the SRX domain of SRα in the GTP-bound state at 3.2 Å, and of GDP- and GDP · Mg(2+)-bound SRβ at 1.9 Å and 2.4 Å, respectively. We define the GTPase switch cycle of SRβ and identify specific differences to the Arf and Sar1 families with implications for GTPase regulation. Our data allow a better integration of SRβ into the scheme of protein targeting.

  20. Unbiased analysis of senescence associated secretory phenotype (SASP) to identify common components following different genotoxic stresses

    PubMed Central

    Özcan, Servet; Alessio, Nicola; Acar, Mustafa B.; Mert, Eda; Omerli, Fatih; Peluso, Gianfranco; Galderisi, Umberto

    2016-01-01

    Senescent cells secrete senescence-associated secretory phenotype (SASP) proteins to carry out several functions, such as sensitizing surrounding cells to senesce; immunomodulation; impairing or fostering cancer growth; and promoting tissue development. Identifying secreted factors that achieve such tasks is a challenging issue since the profile of secreted proteins depends on genotoxic stress and cell type. Currently, researchers are trying to identify common markers for SASP. The present investigation compared the secretome composition of five different senescent phenotypes in two different cell types: bone marrow and adipose mesenchymal stromal cells (MSC). We induced MSC senescence by oxidative stress, doxorubicin treatment, X-ray irradiation, and replicative exhaustion. We took advantage of LC-MS/MS proteome identification and subsequent gene ontology (GO) evaluation to perform an unbiased analysis (hypothesis free manner) of senescent secretomes. GO analysis allowed us to distribute SASP components into four classes: extracellular matrix/cytoskeleton/cell junctions; metabolic processes; ox-redox factors; and regulators of gene expression. We used Ingenuity Pathway Analysis (IPA) to determine common pathways among the different senescent phenotypes. This investigation, along with identification of eleven proteins that were exclusively expressed in all the analyzed senescent phenotypes, permitted the identification of three key signaling paths: MMP2 - TIMP2; IGFBP3 - PAI-1; and Peroxiredoxin 6 - ERP46 - PARK7 - Cathepsin D - Major vault protein. We suggest that these paths could be involved in the paracrine circuit that induces senescence in neighboring cells and may confer apoptosis resistance to senescent cells. PMID:27288264