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Sample records for modulates phagosome maturation

  1. Phagosomal processing of Mycobacterium tuberculosis antigen 85B is modulated independently of mycobacterial viability and phagosome maturation.

    PubMed

    Ramachandra, Lakshmi; Smialek, Jamie L; Shank, Sam S; Convery, Marilyn; Boom, W Henry; Harding, Clifford V

    2005-02-01

    Control of Mycobacterium tuberculosis infection requires CD4 T-cell responses and major histocompatibility complex class II (MHC-II) processing of M. tuberculosis antigens (Ags). We have previously demonstrated that macrophages process heat-killed (HK) M. tuberculosis more efficiently than live M. tuberculosis. These observations suggested that live M. tuberculosis may inhibit Ag processing by inhibiting phagosome maturation or that HK M. tuberculosis may be less resistant to Ag processing. In the present study we examined the correlation between M. tuberculosis viability and phagosome maturation and efficiency of Ag processing. Since heat treatment could render M. tuberculosis Ags more accessible to proteolysis, M. tuberculosis was additionally killed by antibiotic treatment and radiation. Processing of HK, live, radiation-killed (RadK), or rifampin-killed (RifK) M. tuberculosis in activated murine bone marrow macrophages was examined by using an I-A(b)-restricted T-cell hybridoma cell line (BB7) that recognizes an epitope derived from Ag 85B. Macrophages processed HK M. tuberculosis more rapidly and efficiently than they processed live, RadK, or RifK M. tuberculosis. Live, RadK, and RifK M. tuberculosis cells were processed with similar efficiencies for presentation to BB7 T hybridoma cells. Furthermore, phagosomes containing live or RadK M. tuberculosis expressed fewer M. tuberculosis peptide-MHC-II complexes than phagosomes containing HK M. tuberculosis expressed. Since only live M. tuberculosis was able to prevent acidification of the phagosome, our results suggest that regulation of phagosome maturation does not explain the differences in processing of different forms of M. tuberculosis. These findings suggest that the mechanisms used by M. tuberculosis to inhibit phagosomal maturation differ from the mechanisms involved in modulating phagosome Ag processing.

  2. Phagosome maturation: aging gracefully.

    PubMed Central

    Vieira, Otilia V; Botelho, Roberto J; Grinstein, Sergio

    2002-01-01

    Foreign particles and apoptotic bodies are eliminated from the body by phagocytic leucocytes. The initial stage of the elimination process is the internalization of the particles into a plasma membrane-derived vacuole known as the phagosome. Such nascent phagosomes, however, lack the ability to kill pathogens or to degrade the ingested targets. These properties are acquired during the course of phagosomal maturation, a complex sequence of reactions that result in drastic remodelling of the phagosomal membrane and contents. The determinants and consequences of the fusion and fission reactions that underlie phagosomal maturation are the topic of this review. PMID:12061891

  3. Birc1e/Naip5 rapidly antagonizes modulation of phagosome maturation by Legionella pneumophila.

    PubMed

    Fortier, Anne; de Chastellier, Chantal; Balor, Stéphanie; Gros, Philippe

    2007-04-01

    Legionella survives intracellularly by preventing fusion with lysosomes, due to phagosome escape from the endocytic pathway at an early stage of phagosome maturation, and by creating a replicative organelle that acquires endoplasmic reticulum (ER) characteristics through sustained interactions and fusion with the ER. Intracellular replication of Legionella pneumophila in mouse macrophages is controlled by the Lgn1 locus. Functional complementation in vivo has identified the Birc1e/Naip5 gene as being responsible for the Lgn1 effect. To understand the function and temporal site of action of Birc1e/Naip5 in susceptibility to L. pneumophila, we examined the biogenesis of Legionella-containing vacuoles (LCVs) formed in permissive A/J macrophages and in their Birc1e/Naip5 transgenic non-permissive counterpart. Birc1e/Naip5 effects on acquisition of lysosomal and ER markers were evident within 1-2 h following infection. A significantly higher proportion of LCVs formed in Birc1e/Naip5 transgenic macrophages had acquired the lysosomal markers cathepsin D and Lamp1 by 2 h post infection, whereas a significantly higher proportion of LCVs formed in permissive macrophages were positively stained for the ER markers BAP31 and calnexin, 6 h post infection. Likewise, studies by electron microscopy showed acquisition of lysosomal contents (horseradish peroxidase), within the first hour following phagocytic uptake, by LCVs formed in Birc1e/Naip5 transgenic macrophages and delivery of the ER marker glucose 6-phosphatase (G6Pase) only to the lumen of LCVs formed in A/J macrophages. Finally, a larger proportion of LCVs formed in A/J macrophages were studded with ribosomes 24 h post infection, compared with LCVs formed in Birc1e/Naip5 transgenic macrophages. These results suggest that sensing of L. pneumophila products by Birc1e/Naip5 in macrophages occurs rapidly following phagocytosis, a process that antagonizes the ability of L. pneumophila to remodel its phagosome into a specialized

  4. Characterization of the Mycobacterium tuberculosis phagosome and evidence that phagosomal maturation is inhibited

    PubMed Central

    1995-01-01

    We have used the cryosection immunogold technique to study the composition of the Mycobacterium tuberculosis phagosome. We have used quantitative immunogold staining to determine the distribution of several known markers of the endosomal-lysosomal pathway in human monocytes after ingestion of either M. tuberculosis, Legionella pneumophila, or polystyrene beads. Compared with the other phagocytic particles studied, the M. tuberculosis phagosome exhibits delayed clearance of major histocompatibility complex (MHC) class I molecules, relatively intense staining for MHC class II molecules and the endosomal marker transferrin receptor, and relatively weak staining for the lysosomal membrane glycoproteins, CD63, LAMP-1, and LAMP-2 and the lysosomal acid protease, cathepsin D. In contrast to M. tuberculosis, the L. pneumophila phagosome rapidly clears MHC class I molecules and excludes all endosomal-lysosomal markers studied. In contrast to both live M. tuberculosis and L. pneumophila phagosomes, phagosomes containing either polystyrene beads or heat-killed M. tuberculosis stain intensely for lysosomal membrane glycoproteins and cathepsin D. These findings suggest that (a) M. tuberculosis retards the maturation of its phagosome along the endosomal-lysosomal pathway and resides in a compartment with endosomal, as opposed to lysosomal, characteristics; and (b) the intraphagosomal pathway, i.e., the pathway followed by several intracellular parasites that inhibit phagosome-lysosome fusion, is heterogeneous. PMID:7807006

  5. Mycobacterium tuberculosis WhiB3 Responds to Vacuolar pH-induced Changes in Mycothiol Redox Potential to Modulate Phagosomal Maturation and Virulence*

    PubMed Central

    Mehta, Mansi; Rajmani, Raju S.; Singh, Amit

    2016-01-01

    The ability of Mycobacterium tuberculosis to resist intraphagosomal stresses, such as oxygen radicals and low pH, is critical for its persistence. Here, we show that a cytoplasmic redox sensor, WhiB3, and the major M. tuberculosis thiol, mycothiol (MSH), are required to resist acidic stress during infection. WhiB3 regulates the expression of genes involved in lipid anabolism, secretion, and redox metabolism, in response to acidic pH. Furthermore, inactivation of the MSH pathway subverted the expression of whiB3 along with other pH-specific genes in M. tuberculosis. Using a genetic biosensor of mycothiol redox potential (EMSH), we demonstrated that a modest decrease in phagosomal pH is sufficient to generate redox heterogeneity in EMSH of the M. tuberculosis population in a WhiB3-dependent manner. Data indicate that M. tuberculosis needs low pH as a signal to alter cytoplasmic EMSH, which activates WhiB3-mediated gene expression and acid resistance. Importantly, WhiB3 regulates intraphagosomal pH by down-regulating the expression of innate immune genes and blocking phagosomal maturation. We show that this block in phagosomal maturation is in part due to WhiB3-dependent production of polyketide lipids. Consistent with these observations, MtbΔwhiB3 displayed intramacrophage survival defect, which can be rescued bypharmacological inhibition of phagosomal acidification. Last, MtbΔwhiB3 displayed marked attenuation in the lungs of guinea pigs. Altogether, our study revealed an intimate link between vacuolar acidification, redox physiology, and virulence in M. tuberculosis and discovered WhiB3 as crucial mediator of phagosomal maturation arrest and acid resistance in M. tuberculosis. PMID:26637353

  6. Mycobacterium tuberculosis WhiB3 Responds to Vacuolar pH-induced Changes in Mycothiol Redox Potential to Modulate Phagosomal Maturation and Virulence.

    PubMed

    Mehta, Mansi; Rajmani, Raju S; Singh, Amit

    2016-02-05

    The ability of Mycobacterium tuberculosis to resist intraphagosomal stresses, such as oxygen radicals and low pH, is critical for its persistence. Here, we show that a cytoplasmic redox sensor, WhiB3, and the major M. tuberculosis thiol, mycothiol (MSH), are required to resist acidic stress during infection. WhiB3 regulates the expression of genes involved in lipid anabolism, secretion, and redox metabolism, in response to acidic pH. Furthermore, inactivation of the MSH pathway subverted the expression of whiB3 along with other pH-specific genes in M. tuberculosis. Using a genetic biosensor of mycothiol redox potential (EMSH), we demonstrated that a modest decrease in phagosomal pH is sufficient to generate redox heterogeneity in EMSH of the M. tuberculosis population in a WhiB3-dependent manner. Data indicate that M. tuberculosis needs low pH as a signal to alter cytoplasmic EMSH, which activates WhiB3-mediated gene expression and acid resistance. Importantly, WhiB3 regulates intraphagosomal pH by down-regulating the expression of innate immune genes and blocking phagosomal maturation. We show that this block in phagosomal maturation is in part due to WhiB3-dependent production of polyketide lipids. Consistent with these observations, MtbΔwhiB3 displayed intramacrophage survival defect, which can be rescued bypharmacological inhibition of phagosomal acidification. Last, MtbΔwhiB3 displayed marked attenuation in the lungs of guinea pigs. Altogether, our study revealed an intimate link between vacuolar acidification, redox physiology, and virulence in M. tuberculosis and discovered WhiB3 as crucial mediator of phagosomal maturation arrest and acid resistance in M. tuberculosis.

  7. Role of JAK-STAT signaling in maturation of phagosomes containing Staphylococcus aureus

    PubMed Central

    Zhu, Fei; Zhou, Yadong; Jiang, Chunxia; Zhang, Xiaobo

    2015-01-01

    Phagocytosis is a required mechanism for the defense against pathogens. Staphylococcus aureus, an important bacterial pathogen, can promptly escape from phagosomes and proliferate within the cytoplasm of host. However, the mechanism of phagocytosis against S. aureus has not been intensively investigated. In this study, the S. aureus was engulfed by macrophages (RAW264.7 cells) but not digested by the cells, suggesting that the phagosomes did not maturate in macrophages. Further investigation revealed that peptidoglycan (PG) induced the phagosome maturation of macrophages, resulting in the eradication of S. aureus. Genome-wide analysis and quantitative real-time PCR indicated that the JAK-STAT pathway was activated by PG during the phagosome maturation of macrophages against S. aureus. This finding presented that the PG-activated JAK-STAT pathway was required for phagosome maturation. Therefore, our study contributed evidence that revealed a novel aspect of PG-triggered JAK-STAT pathway in the phagosome maturation of macrophages. PMID:26442670

  8. The HIV-1 protein Vpr impairs phagosome maturation by controlling microtubule-dependent trafficking

    PubMed Central

    Dumas, Audrey; Lê-Bury, Gabrielle; Marie-Anaïs, Florence; Herit, Floriane; Mazzolini, Julie; Guilbert, Thomas; Bourdoncle, Pierre; Russell, David G.; Benichou, Serge; Zahraoui, Ahmed

    2015-01-01

    Human immunodeficiency virus type 1 (HIV-1) impairs major functions of macrophages but the molecular basis for this defect remains poorly characterized. Here, we show that macrophages infected with HIV-1 were unable to respond efficiently to phagocytic triggers and to clear bacteria. The maturation of phagosomes, defined by the presence of late endocytic markers, hydrolases, and reactive oxygen species, was perturbed in HIV-1–infected macrophages. We showed that maturation arrest occurred at the level of the EHD3/MICAL-L1 endosomal sorting machinery. Unexpectedly, we found that the regulatory viral protein (Vpr) was crucial to perturb phagosome maturation. Our data reveal that Vpr interacted with EB1, p150Glued, and dynein heavy chain and was sufficient to critically alter the microtubule plus end localization of EB1 and p150Glued, hence altering the centripetal movement of phagosomes and their maturation. Thus, we identify Vpr as a modulator of the microtubule-dependent endocytic trafficking in HIV-1–infected macrophages, leading to strong alterations in phagolysosome biogenesis. PMID:26504171

  9. Cutting edge: FYCO1 recruitment to dectin-1 phagosomes is accelerated by light chain 3 protein and regulates phagosome maturation and reactive oxygen production.

    PubMed

    Ma, Jun; Becker, Courtney; Reyes, Christopher; Underhill, David M

    2014-02-15

    L chain 3 (LC3)-associated phagocytosis is a process in which LC3, a protein canonically involved in engulfing intracellular materials (autophagy), is recruited to traditional phagosomes during internalization of extracellular payloads. LC3's association with phagosomes has been implicated in regulating microbial killing, Ag processing, and phagosome maturation; however, the mechanism by which LC3 influences these processes has not been clear. In this study, we report that FYVE and coiled-coil domain containing 1 (FYCO1), a protein previously implicated in autophagosome trafficking, is recruited directly by LC3 to Dectin-1 phagosomes. During LC3-associated phagocytosis, FYCO1 recruitment facilitates maturation of early p40phox(+) phagosomes into late LAMP1(+) phagosomes. When FYCO1 is lacking, phagosomes stay p40phox(+) longer and produce more reactive oxygen.

  10. Rab20 regulates phagosome maturation in RAW264 macrophages during Fc gamma receptor-mediated phagocytosis.

    PubMed

    Egami, Youhei; Araki, Nobukazu

    2012-01-01

    Rab20, a member of the Rab GTPase family, is known to be involved in membrane trafficking, however its implication in FcγR-mediated phagocytosis is unclear. We examined the spatiotemporal localization of Rab20 during phagocytosis of IgG-opsonized erythrocytes (IgG-Es) in RAW264 macrophages. By the live-cell imaging of fluorescent protein-fused Rab20, it was shown that Rab20 was transiently associated with the phagosomal membranes. During the early stage of phagosome formation, Rab20 was not localized on the membranes of phagocytic cups, but was gradually recruited to the newly formed phagosomes. Although Rab20 was colocalized with Rab5 to some extent, the association of Rab20 with the phagosomes persisted even after the loss of Rab5 from the phagosomal membranes. Then, Rab20 was colocalized with Rab7 and Lamp1, late endosomal/lysosomal markers, on the internalized phagosomes. Moreover, our analysis of Rab20 mutant expression revealed that the maturation of phagosomes was significantly delayed in cells expressing the GDP-bound mutant Rab20-T19N. These data suggest that Rab20 is an important component of phagosome and regulates the phagosome maturation during FcγR-mediated phagocytosis.

  11. Proteomics fingerprinting of phagosome maturation and evidence for the role of a Galpha during uptake.

    PubMed

    Gotthardt, Daniel; Blancheteau, Vincent; Bosserhoff, Armin; Ruppert, Thomas; Delorenzi, Mauro; Soldati, Thierry

    2006-12-01

    Phagocytosis, whether of food particles in protozoa or bacteria and cell remnants in the metazoan immune system, is a conserved process. The particles are taken up into phagosomes, which then undergo complex remodeling of their components, called maturation. By using two-dimensional gel electrophoresis and mass spectrometry combined with genomic data, we identified 179 phagosomal proteins in the amoeba Dictyostelium, including components of signal transduction, membrane traffic, and the cytoskeleton. By carrying out this proteomics analysis over the course of maturation, we obtained time profiles for 1,388 spots and thus generated a dynamic record of phagosomal protein composition. Clustering of the time profiles revealed five clusters and 24 functional groups that were mapped onto a flow chart of maturation. Two heterotrimeric G protein subunits, Galpha4 and Gbeta, appeared at the earliest times. We showed that mutations in the genes encoding these two proteins produce a phagocytic uptake defect in Dictyostelium. This analysis of phagosome protein dynamics provides a reference point for future genetic and functional investigations.

  12. Mycobacterium bovis Requires P27 (LprG) To Arrest Phagosome Maturation and Replicate within Bovine Macrophages

    PubMed Central

    Vázquez, Cristina Lourdes; Bianco, María Verónica; Blanco, Federico Carlos; Forrellad, Marina Andrea; Gutierrez, Maximiliano Gabriel

    2016-01-01

    ABSTRACT Mycobacterium bovis causes tuberculosis in a wide variety of mammals, with strong tropism for cattle and eventually humans. P27, also called LprG, is among the proteins involved in the mechanisms of the virulence and persistence of M. bovis and Mycobacterium tuberculosis. Here, we describe a novel function of P27 in the interaction of M. bovis with its natural host cell, the bovine macrophage. We found that a deletion in the p27-p55 operon impairs the replication of M. bovis in bovine macrophages. Importantly, we show for the first time that M. bovis arrests phagosome maturation in a process that depends on P27. This effect is P27 specific since complementation with wild-type p27 but not p55 fully restored the wild-type phenotype of the mutant strain; this indicates that P55 plays no important role during the early events of M. bovis infection. In addition, we also showed that the presence of P27 from M. smegmatis decreases the association of LAMP-3 with bead phagosomes, indicating that P27 itself blocks phagosome-lysosome fusion by modulating the traffic machinery in the cell host. PMID:28031264

  13. Infection of porcine bone marrow-derived macrophages by porcine respiratory and reproductive syndrome virus impairs phagosomal maturation.

    PubMed

    Chaudhuri, Sibapriya; McKenna, Neil; Balce, Dale R; Yates, Robin M

    2016-03-01

    Porcine reproductive and respiratory syndrome virus (PRRSV), a positive-sense, ssRNA virus of the genus Arterivirus, is a devastating disease of swine worldwide. Key early targets of PRRSV infection in pigs include professional phagocytes in the lung, such as alveolar and interstitial macrophages and dendritic cells, the dysfunction of which is believed to be responsible for much of the associated mortality. In order to study the effect of virus infection on phagocyte function, the development of a robust, reproducible model would be advantageous. Given the limitations of current models, we set out to develop a porcine bone marrow-derived macrophage (PBMMΦ) cell model to study phagosomal maturation and function during PRRSV infection. Derivation of PBMMΦs from marrow using cultured L929 fibroblast supernatant produced a homogeneous population of cells that exhibited macrophage-like morphology and proficiency in Fc-receptor-mediated phagocytosis and phagosomal maturation. PBMMΦs were permissive to PRRSV infection, resulting in a productive infection that peaked at 24 h. Assessment of the effect of PRRSV infection on the properties of phagosomal maturation in PBMMΦs revealed a significant decrease in phagosomal proteolysis and lowered production of reactive oxygen species, but no change in PBMMΦ viability, phagocytosis or the ability of phagosomes to acidify. In this study, we present a new model to investigate PRRSV infection of phagocytes, which demonstrates a significant effect on phagosomal maturation with the associated implications on proper macrophage function. This model can also be used to study the effect on the phagosomal microenvironment of infection by other viruses targeting porcine macrophages.

  14. IL-10 Produced by Trophoblast Cells Inhibits Phagosome Maturation Leading to Profound Intracellular Proliferation of Salmonella enterica Typhimurium

    PubMed Central

    Nguyen, Tina; Robinson, Nirmal; Allison, Sarah E.; Coombes, Brian K; Sad, Subash; Krishnan, Lakshmi

    2013-01-01

    Introduction Salmonella enterica Typhimurium (ST) is a phagosomal pathogen that can infect placental trophoblast cells leading to abortion and severe maternal illness. It is unclear how the trophoblast cells promote profound bacterial proliferation. Methods The mechanism of internalization, intracellular growth and phagosomal biogenesis in ST-infected human epithelial (HeLa), macrophage (THP-1) and trophoblast-derived cell lines (JEG-3, BeWo and HTR-8) was studied. Specific inhibitors were used to block bacterial internalization. Phagosomal maturation was determined by confocal microscopy, western-blotting and release of lysosomal β-galactosidase by infected cells. Bacterial colony forming units were determined by plating infected cell lysates on agar plates. Results ST proliferated minimally in macrophages but replicated profoundly within trophoblast cells. The ST-∆invA (a mutant of Salmonella pathogenicity island-1 gene effector proteins) was unable to infect epithelial.cells, but was internalized by scavenger receptors on trophoblasts and macrophages. However, ST was contrastingly localized in early (Rab5+) or late (LAMP1+) phagosomes within trophoblast cells and macrophages respectively. Furthermore trophoblast cells (unlike macrophages) did not exhibit phagoso-lysosomal fusion. ST-infected macrophages produced IL-6 whereas trophoblast cells produced IL-10. Neutralizing IL-10 in JEG-3 cells accelerated phagolysomal fusion and reduced proliferation of ST. Placental bacterial burden was curtailed in vivo in anti-IL-10 antibody treated and IL-10-deficient mice. Discussion Macrophages phagocytose but curtail intracellular replication of ST in late phagosomes. In contrast, phagocytosis by trophoblast cells results in an inappropriate cytokine response and proliferation of ST in early phagosomes. Conclusion IL-10 production by trophoblast cells that delays phagosomal maturation may facilitate proliferation of pathogens in placental cells. PMID:23834952

  15. A Conserved Role for SNX9-Family Members in the Regulation of Phagosome Maturation during Engulfment of Apoptotic Cells

    PubMed Central

    Kinchen, Jason M.; Kaech, Andres; Ravichandran, Kodi S.; Hengartner, Michael O.

    2011-01-01

    Clearance of apoptotic cells is of key importance during development, tissue homeostasis and wound healing in multi-cellular animals. Genetic studies in the nematode Caenorhabditis elegans have identified a set of genes involved in the early steps of cell clearance, in particular the recognition and internalization of apoptotic cells. A pathway that orchestrates the maturation of phagosomes containing ingested apoptotic cells in the worm has recently been described. However, many steps in this pathway remain elusive. Here we show that the C. elegans SNX9-family member LST-4 (lateral signaling target) and its closest mammalian orthologue SNX33 play an evolutionary conserved role during apoptotic cell corpse clearance. In lst-4 deficient worms, internalized apoptotic cells accumulated within non-acidified, DYN-1-positive but RAB-5-negative phagosomes. Genetically, we show that LST-4 functions at the same step as DYN-1 during corpse removal, upstream of the GTPase RAB-5. We further show that mammalian SNX33 rescue C. elegans lst-4 mutants and that overexpression of truncated SNX33 fragments interfered with phagosome maturation in a mammalian cell system. Taken together, our genetic and cell biological analyses suggest that LST-4 is recruited through a combined activity of DYN-1 and VPS-34 to the early phagosome membrane, where it cooperates with DYN-1 to promote recruitment/retention of RAB-5 on the early phagosomal membrane during cell corpse clearance. The functional conservation between LST-4 and SNX33 indicate that these early steps of apoptotic phagosome maturation are likely conserved through evolution. PMID:21494661

  16. Mycobacterium requires an all-around closely apposing phagosome membrane to maintain the maturation block and this apposition is re-established when it rescues itself from phagolysosomes.

    PubMed

    de Chastellier, Chantal; Forquet, Frédérique; Gordon, Alon; Thilo, Lutz

    2009-08-01

    Pathogenic mycobacteria survive in macrophages of the host organism by residing in phagosomes which they prevent from undergoing maturation and fusion with lysosomes. Several molecular mechanisms have been associated with the phagosome maturation block. Here we show for Mycobacterium avium in mouse bone marrow-derived macrophages that the maturation block required an all-around close apposition between the mycobacterial surface and the phagosome membrane. When small (0.1 microm) latex beads were covalently attached to the mycobacterial surface to act as a spacer that interfered with a close apposition, phagosomes rapidly acquired lysosomal characteristics as indicators for maturation and fusion with lysosomes. As a result, several mycobacteria were delivered into single phagolysosomes. Detailed electron-microscope observations of phagosome morphology over a 7-day post-infection period showed a linear correlation between bead attachment and phagosome-lysosome fusion. After about 3 days post infection, conditions inside phagolysosomes caused a gradual release of beads. This allowed mycobacteria to re-establish a close apposition with the surrounding membrane and sequester themselves into individual, non-maturing phagosomes which had lost lysosomal characteristics. By rescuing themselves from phagolysosomes, mycobacteria remained fully viable and able to multiply at the normal rate. In order to unify the present observations and previously reported mechanisms for the maturation block, we discuss evidence that they may act synergistically to interfere with 'Phagosome Membrane Economics' by causing relative changes in incoming and outgoing endocytic membrane fluxes.

  17. Attenuated Leishmania induce pro-inflammatory mediators and influence leishmanicidal activity by p38 MAPK dependent phagosome maturation in Leishmania donovani co-infected macrophages.

    PubMed

    Banerjee, Somenath; Bose, Dipayan; Chatterjee, Nabanita; Das, Subhadip; Chakraborty, Sreeparna; Das, Tanya; Saha, Krishna Das

    2016-03-01

    Promastigote form of Leishmania, an intracellular pathogen, delays phagosome maturation and resides inside macrophages. But till date limited study has been done to manipulate the phagosomal machinery of macrophages to restrict Leishmania growth. Attenuated Leishmania strain exposed RAW 264.7 cells showed a respiratory burst and enhanced production of pro-inflammatory mediators. The augmentation of pro-inflammatory activity is mostly attributed to p38 MAPK and p44/42 MAPK. In our study, these activated macrophages are found to induce phagosome maturation when infected with pathogenic Leishmania donovani. Increased co-localization of carboxyfluorescein succinimidyl ester labeled pathogenic L. donovani with Lysosome was found. Moreover, increased co-localization was observed between pathogenic L. donovani and late phagosomal markers viz. Rab7, Lysosomal Associated Membrane Protein 1, Cathepsin D, Rab9, and V-ATPase which indicate phagosome maturation. It was also observed that inhibition of V-type ATPase caused significant hindrance in attenuated Leishmania induced phagosome maturation. Finally, it was confirmed that p38 MAPK is the key player in acidification and maturation of phagosome in attenuated Leishmania strain pre-exposed macrophages. To our knowledge, this study for the first time reported an approach to induce phagosome maturation in L. donovani infected macrophages which could potentiate short-term prophylactic response in future.

  18. Naturally produced opsonizing antibodies restrict the survival of Mycobacterium tuberculosis in human macrophages by augmenting phagosome maturation

    PubMed Central

    Kumar, Shashi Kant; Singh, Padam; Sinha, Sudhir

    2015-01-01

    This study investigated the hypothesis that serum antibodies against Mycobacterium tuberculosis present in naturally infected healthy subjects of a tuberculosis (TB) endemic area could create and/or sustain the latent form of infection. All five apparently healthy Indian donors showed high titres of serum antibodies against M. tuberculosis cell membrane antigens, including lipoarabinomannan and alpha crystallin. Uptake and killing of bacilli by the donor macrophages was significantly enhanced following their opsonization with antibody-rich, heat-inactivated autologous sera. However, the capability to opsonize was apparent for antibodies against some and not other antigens. High-content cell imaging of infected macrophages revealed significantly enhanced colocalization of the phagosome maturation marker LAMP-1, though not of calmodulin, with antibody-opsonized compared with unopsonized M. tuberculosis. Key enablers of macrophage microbicidal action—proinflammatory cytokines (IFN-γ and IL-6), phagosome acidification, inducible NO synthase and nitric oxide—were also significantly enhanced following antibody opsonization. Interestingly, heat-killed M. tuberculosis also elevated these mediators to the levels comparable to, if not higher than, opsonized M. tuberculosis. Results of the study support the emerging view that an efficacious vaccine against TB should, apart from targeting cell-mediated immunity, also generate ‘protective’ antibodies. PMID:26674415

  19. Caspase-11 promotes the fusion of phagosomes harboring pathogenic bacteria with lysosomes by modulating actin polymerization.

    PubMed

    Akhter, Anwari; Caution, Kyle; Abu Khweek, Arwa; Tazi, Mia; Abdulrahman, Basant A; Abdelaziz, Dalia H A; Voss, Oliver H; Doseff, Andrea I; Hassan, Hoda; Azad, Abul K; Schlesinger, Larry S; Wewers, Mark D; Gavrilin, Mikhail A; Amer, Amal O

    2012-07-27

    Inflammasomes are multiprotein complexes that include members of the NLR (nucleotide-binding domain leucine-rich repeat containing) family and caspase-1. Once bacterial molecules are sensed within the macrophage, the inflammasome is assembled, mediating the activation of caspase-1. Caspase-11 mediates caspase-1 activation in response to lipopolysaccharide and bacterial toxins, and yet its role during bacterial infection is unknown. Here, we demonstrated that caspase-11 was dispensable for caspase-1 activation in response to Legionella, Salmonella, Francisella, and Listeria. We also determined that active mouse caspase-11 was required for restriction of L. pneumophila infection. Similarly, human caspase-4 and caspase-5, homologs of mouse caspase-11, cooperated to restrict L. pneumophila infection in human macrophages. Caspase-11 promoted the fusion of the L. pneumophila vacuole with lysosomes by modulating actin polymerization through cofilin. However, caspase-11 was dispensable for the fusion of lysosomes with phagosomes containing nonpathogenic bacteria, uncovering a fundamental difference in the trafficking of phagosomes according to their cargo.

  20. Caspase-11 promotes the fusion of phagosomes harboring pathogenic bacteria with lysosomes by modulating actin polymerization

    PubMed Central

    Akhter, Anwari; Caution, Kyle; Khweek, Arwa Abu; Tazi, Mia; Abdulrahman, Basant A.; Abdelaziz, Dalia H.A.; Voss, Oliver H.; Doseff, Andrea I.; Hassan, Hoda; Azad, Abul K.; Schlesinger, Larry S.; Wewers, Mark D.; Gavrilin, Mikhail A.; Amer, Amal O.

    2012-01-01

    Summary Inflammasomes are multiprotein complexes that include members of the NLR (nucleotide-binding domain leucine-rich repeat containing) family and caspase-1. Once bacterial molecules are sensed within the macrophage, the inflammasome is assembled mediating the activation of caspase-1. Caspase-11 mediates caspase-1 activation in response to lipopolysaccharide and bacterial toxins. Yet, its role during bacterial infection is unknown. Here, we demonstrated that caspase-11 was dispensable for caspase-1 activation in response to Legionella, Salmonella, Francisella and Listeria. We also determined that active mouse caspase-11 was required for restriction of L. pneumophila infection. Similarly, human caspase-4 and 5, homologs of mouse caspase-11, cooperated to restrict L. pneumophila infection in human macrophages. Caspase-11 promoted the fusion of the L. pneumophila- vacuole with lysosomes by modulating actin polymerization through cofilin. However, caspase-11 was dispensable for the fusion of lysosomes with phagosomes containing non-pathogenic bacteria, uncovering a fundamental difference in the trafficking of phagosomes according to their cargo. PMID:22658523

  1. Cholesterol depletion in Mycobacterium avium-infected macrophages overcomes the block in phagosome maturation and leads to the reversible sequestration of viable mycobacteria in phagolysosome-derived autophagic vacuoles.

    PubMed

    de Chastellier, Chantal; Thilo, Lutz

    2006-02-01

    Phagocytic entry of mycobacteria into macrophages requires the presence of cholesterol in the plasma membrane. This suggests that pathogenic mycobacteria may require cholesterol for their subsequent intra-cellular survival in non-maturing phagosomes. Here we report on the effect of cholesterol depletion on pre-existing phagosomes in mouse bone marrow-derived macrophages infected with Mycobacterium avium. Cholesterol depletion with methyl-beta-cyclodextrin resulted in a loosening of the close apposition between the phagosome membrane and the mycobacterial surface, followed by fusion with lysosomes. The resulting phagolysosomes then autonomously executed autophagy, which did not involve the endoplasmic reticulum. After 5 h of depletion, intact mycobacteria had accumulated in large auto-phagolysosomes. Autophagy was specific for phagolysosomes that contained mycobacteria, as it did not involve latex bead-containing phagosomes in infected cells. Upon replenishment of cholesterol, mycobacteria became increasingly aligned to the lysosomal membrane, from where they were individually sequestered in phagosomes with an all-around closely apposed phagosome membrane and which no longer fused with lysosomes. These observations indicate that, cholesterol depletion (i) resulted in phagosome maturation and fusion with lysosomes and (ii) caused mycobacterium-containing phagolysosomes to autonomously undergo autophagy. Furthermore, (iii) mycobacteria were not killed in auto-phagolysosomes, and (iv) cholesterol replenishment enabled mycobacterium to rescue itself from autophagic phagolysosomes to again reside individually in phagosomes which no longer fused with lysosomes.

  2. Inhibition of phagosome maturation by mycobacteria does not interfere with presentation of mycobacterial antigens by MHC molecules.

    PubMed

    Majlessi, Laleh; Combaluzier, Benoit; Albrecht, Imke; Garcia, Jessica E; Nouze, Clémence; Pieters, Jean; Leclerc, Claude

    2007-08-01

    Pathogenic mycobacteria escape host innate immune responses by surviving within phagosomes of host macrophages and blocking their delivery to lysosomes. Avoiding lysosomal delivery may also be involved in the capacity of living mycobacteria to modulate MHC class I- or II-dependent T cell responses, which may contribute to their pathogenicity in vivo. In this study, we show that the presentation of mycobacterial Ags is independent of the site of intracellular residence inside professional APCs. Infection of mouse macrophages or dendritic cells in vitro with mycobacterial mutants that are unable to escape lysosomal transfer resulted in an identical efficiency of Ag presentation compared with wild-type mycobacteria. Moreover, in vivo, such mutants induced CD4(+) Th1 or CD8(+) CTL responses in mice against various mycobacterial Ags that were comparable to those induced by their wild-type counterparts. These results suggest that the limiting factor for the generation of an adaptive immune response against mycobacteria is not the degree of lysosomal delivery. These findings are important in the rational design of improved vaccines to combat mycobacterial diseases.

  3. CLIC1 regulates dendritic cell antigen processing and presentation by modulating phagosome acidification and proteolysis

    PubMed Central

    Salao, Kanin; Jiang, Lele; Li, Hui; Tsai, Vicky W.-W.; Husaini, Yasmin; Curmi, Paul M. G.; Brown, Louise J.; Brown, David A.

    2016-01-01

    ABSTRACT Intracellular chloride channel protein 1 (CLIC1) participates in inflammatory processes by regulating macrophage phagosomal functions such as pH and proteolysis. Here, we sought to determine if CLIC1 can regulate adaptive immunity by actions on dendritic cells (DCs), the key professional antigen presenting cells. To do this, we first generated bone marrow-derived DCs (BMDCs) from germline CLIC1 gene-deleted (CLIC1−/−) and wild-type (CLIC1+/+) mice, then studied them in vitro and in vivo. We found phagocytosis triggered cytoplasmic CLIC1 translocation to the phagosomal membrane where it regulated phagosomal pH and proteolysis. Phagosomes from CLIC1−/− BMDCs displayed impaired acidification and proteolysis, which could be reproduced if CLIC1+/+, but not CLIC1−/− cells, were treated with IAA94, a CLIC family ion channel blocker. CLIC1−/− BMDC displayed reduced in vitro antigen processing and presentation of full-length myelin oligodendrocyte glycoprotein (MOG) and reduced MOG-induced experimental autoimmune encephalomyelitis. These data suggest that CLIC1 regulates DC phagosomal pH to ensure optimal processing of antigen for presentation to antigen-specific T-cells. Further, they indicate that CLIC1 is a novel therapeutic target to help reduce the adaptive immune response in autoimmune diseases. PMID:27113959

  4. Identification of the Mycobacterium tuberculosis protein PE-PGRS62 as a novel effector that functions to block phagosome maturation and inhibit iNOS expression.

    PubMed

    Thi, Emily P; Hong, Chris Joon Ho; Sanghera, Gaganjit; Reiner, Neil E

    2013-05-01

    Using a genetic screen in yeast we found that Mycobacterium tuberculosis PE-PGRS62 was capable of disrupting yeast vacuolar protein sorting, suggesting effects on endosomal trafficking. To study the impact of PE-PGRS62 on macrophage function, we infected murine macrophages with Mycobacterium smegmatis expressing PE-PGRS62. Infected cells displayed phagosome maturation arrest. Phagosomes acquired Rab5, but displayed a significant defect in Rab7 and LAMP-1 acquisition. Macrophages infected with M. smegmatis expressing PE-PGRS62 also expressed two- to threefold less iNOS protein when compared with cells infected with wild-type bacteria. Consistent with this, cells infected with a Mycobacterium marinum transposon mutant for the PE-PGRS62 orthologue showed greater iNOS protein expression when compared to cells infected with wild-type organisms. Complementation restored the ability of the mutant to inhibit iNOS expression. No differences in iNOS transcript levels were observed, suggesting that PE-PGRS62 effects on iNOS expression occurred post-transcriptionally. Marked differences in colony morphology were also seen in M. smegmatis expressing PE-PGRS62 and in the M. marinum transposon mutant, suggesting that PE-PGRS62 may affect cell wall composition. These findings suggest that PE-PGRS62 supports virulence via inhibition of phagosome maturation and iNOS expression, and these phenotypes may be linked to effects on bacterial cell wall composition.

  5. Dectin-1 Controls TLR9 Trafficking to Phagosomes containing β-1,3 glucan123

    PubMed Central

    Khan, Nida S.; Kasperkovitz, Pia V.; Timmons, Allison K.; Mansour, Michael K.; Tam, Jenny M.; Seward, Michael W.; Reedy, Jennifer L.; Puranam, Sravanthi; Feliu, Marianela; Vyas, Jatin M.

    2016-01-01

    Dectin-1 and TLR9 play distinct roles in the recognition and induction of innate immune responses to Aspergillus fumigatus and Candida albicans. Dectin-1 is a receptor for the major fungal cell wall carbohydrate β-1,3 glucan that induces inflammatory cytokines and controls phagosomal maturation through Syk activation. TLR9 is an endosomal Toll-like receptor that also modulates the inflammatory cytokine response to fungal pathogens. In this study, we demonstrate that β-1,3 glucan beads are sufficient to induce dynamic redistribution and accumulation of cleaved TLR9 to phagosomes. Trafficking of TLR9 to A. fumigatus and C. albicans phagosomes requires Dectin-1 recognition. Inhibition of phagosomal acidification blocks TLR9 accumulation on phagosomes containing β-1,3 glucan beads. Dectin-1 mediated Syk activation is required for TLR9 trafficking to β-1,3 glucan, A. fumigatus, and C. albicans containing phagosomes. In addition, Dectin-1 regulates TLR9 dependent gene expression. Collectively, our study demonstrates that recognition of β-1,3 glucan by Dectin-1 triggers TLR9 trafficking to β-1,3 glucan-containing phagosomes, which may be critical in coordinating innate anti-fungal defense. PMID:26829985

  6. Salmonella modulation of the phagosome membrane, role of SseJ.

    PubMed

    Kolodziejek, Anna M; Miller, Samuel I

    2015-03-01

    Salmonellae have the ability to invade, persist and replicate within an intracellular phagosome termed the Salmonella-containing vacuole (SCV). Salmonellae alter lipid and protein content of the SCV membrane and manipulate cytoskeletal elements in contact with the SCV using the Salmonella pathogenicity island 1 (SPI-2) type III secretion system effectors. These modifications result in microtubular-based movement and morphological changes, which include endosomal tubulation of the SCV membrane. SseJ is a SPI-2 effector that localizes to the cytoplasmic face of the SCV and esterifies cholesterol through its glycerophospholipid : cholesterol acyltransferase activity. SseJ enzymatic activity as well as localization to the SCV are determined by binding to the small mammalian GTPase, RhoA. This review will focus on current knowledge about the role of SseJ in SCV membrane modification and will discuss how the hypothesis that a major role of SPI-2 effectors is to modify SCV protein and lipid content to promote bacterial intracellular survival.

  7. Assessing the Phagosome Proteome by Quantitative Mass Spectrometry.

    PubMed

    Peltier, Julien; Härtlova, Anetta; Trost, Matthias

    2017-01-01

    Phagocytosis is the process that engulfs particles in vesicles called phagosomes that are trafficked through a series of maturation steps, culminating in the destruction of the internalized cargo. Because phagosomes are in direct contact with the particle and undergo constant fusion and fission events with other organelles, characterization of the phagosomal proteome is a powerful tool to understand mechanisms controlling innate immunity as well as vesicle trafficking. The ability to isolate highly pure phagosomes through the use of latex beads led to an extensive use of proteomics to study phagosomes under different stimuli. Thousands of different proteins have been identified and quantified, revealing new properties and shedding new light on the dynamics and composition of maturing phagosomes and innate immunity mechanisms. In this chapter, we describe how quantitative-based proteomic methods such as label-free, dimethyl labeling or Tandem Mass Tag (TMT) labeling can be applied for the characterization of protein composition and translocation during maturation of phagosomes in macrophages.

  8. Analysis of Phagosomal Antigen Degradation by Flow Organellocytometry

    PubMed Central

    Hoffmann, Eik; Pauwels, Anne-Marie; Alloatti, Andrés; Kotsias, Fiorella; Amigorena, Sebastian

    2017-01-01

    Professional phagocytes internalize self and non-self particles by phagocytosis to initiate innate immune responses. After internalization, the formed phagosome matures through fusion and fission events with endosomes and lysosomes to obtain a more acidic, oxidative and hydrolytic environment for the degradation of its cargo. Interestingly, phagosome maturation kinetics differ between cell types and cell activation states. This protocol allows to quantify phagosome maturation kinetics on a single organelle level in different types of phagocytes using flow cytometry. Here, ovalbumin (OVA)-coupled particles are used as phagocytosis model system in dendritic cells (DC), which are internalized by phagocytosis. After different time points, phagosome maturation parameters, such as phagosomal degradation of OVA and acquisition of lysosomal proteins (like LAMP-1), can be measured simultaneously in a highly quantitative manner by flow organellocytometry. These read-outs can be correlated to other phagosomal functions, for example antigen degradation, processing and loading in DC. PMID:28239620

  9. Membrane proteomics of phagosomes suggests a connection to autophagy

    SciTech Connect

    Shui, Wenqing; Sheu, Leslie; Liu, Jun; Smart, Brian; Petzold, Christopher J.; Hsieh, Tsung-yen; Pitcher, Austin; Keasling*, Jay D.; Bertozzi*, Carolyn R.

    2008-11-25

    Phagocytosis is the central process by which macrophage cellsinternalize and eliminate infectious microbes as well as apoptoticcells. During maturation, phagosomes containing engulfed particlesfuse with various endosomal compartments through theaction of regulatory molecules on the phagosomal membrane. Inthis study, we performed a proteomic analysis of the membranefraction from latex bead-containing (LBC) phagosomes isolatedfrom macrophages. The profile, which comprised 546 proteins,suggests diverse functions of the phagosome and potential connectionsto secretory processes, toll-like receptor signaling, andautophagy. Many identified proteins were not previously knownto reside in the phagosome. We characterized several proteins inLBC phagosomes that change in abundance on induction of autophagy,a process that has been previously implicated in the hostdefense against microbial pathogens. These observations suggestcrosstalk between autophagy and phagocytosis that may be relevantto the innate immune response of macrophages.

  10. Brucella suis-Impaired Specific Recognition of Phagosomes by Lysosomes due to Phagosomal Membrane Modifications

    PubMed Central

    Naroeni, Aroem; Jouy, Nicolas; Ouahrani-Bettache, Safia; Liautard, Jean-Pierre; Porte, Françoise

    2001-01-01

    Brucella species are gram-negative, facultatively intracellular bacteria that infect humans and animals. These organisms can survive and replicate within a membrane-bound compartment in phagocytic and nonprofessional phagocytic cells. Inhibition of phagosome-lysosome fusion has been proposed as a mechanism for intracellular survival in both types of cells. However, the biochemical mechanisms and microbial factors implicated in Brucella maturation are still completely unknown. We developed two different approaches in an attempt to gain further insight into these mechanisms: (i) a fluorescence microscopy analysis of general intracellular trafficking on whole cells in the presence of Brucella and (ii) a flow cytometry analysis of in vitro reconstitution assays showing the interaction between Brucella suis-containing phagosomes and lysosomes. The fluorescence microscopy results revealed that fusion properties of latex bead-containing phagosomes with lysosomes were not modified in the presence of live Brucella suis in the cells. We concluded that fusion inhibition was restricted to the pathogen phagosome and that the host cell fusion machinery was not altered by the presence of live Brucella in the cell. By in vitro reconstitution experiments, we observed a specific association between killed B. suis-containing phagosomes and lysosomes, which was dependent on exogenously supplied cytosol, energy, and temperature. This association was observed with killed bacteria but not with live bacteria. Hence, this specific recognition inhibition seemed to be restricted to the pathogen phagosomal membrane, as noted in the in vivo experiments. PMID:11119541

  11. The Mycobacterium bovis Bacille Calmette-Guérin Phagosome Proteome*

    PubMed Central

    Lee, Bai-Yu; Jethwaney, Deepa; Schilling, Birgit; Clemens, Daniel L.; Gibson, Bradford W.; Horwitz, Marcus A.

    2010-01-01

    Mycobacterium tuberculosis and Mycobacterium bovis bacille Calmette-Guérin (BCG) alter the maturation of their phagosomes and reside within a compartment that resists acidification and fusion with lysosomes. To define the molecular composition of this compartment, we developed a novel method for obtaining highly purified phagosomes from BCG-infected human macrophages and analyzed the phagosomes by Western immunoblotting and mass spectrometry-based proteomics. Our purification procedure revealed that BCG grown on artificial medium becomes less dense after growth in macrophages. By Western immunoblotting, LAMP-2, Niemann-Pick protein C1, and syntaxin 3 were readily detectable on the BCG phagosome but at levels that were lower than on the latex bead phagosome; flotillin-1 and the vacuolar ATPase were barely detectable on the BCG phagosome but highly enriched on the latex bead phagosome. Immunofluorescence studies confirmed the scarcity of flotillin on BCG phagosomes and demonstrated an inverse correlation between bacterial metabolic activity and flotillin on M. tuberculosis phagosomes. By mass spectrometry, 447 human host proteins were identified on BCG phagosomes, and a partially overlapping set of 289 human proteins on latex bead phagosomes was identified. Interestingly, the majority of the proteins identified consistently on BCG phagosome preparations were also identified on latex bead phagosomes, indicating a high degree of overlap in protein composition of these two compartments. It is likely that many differences in protein composition are quantitative rather than qualitative in nature. Despite the remarkable overlap in protein composition, we consistently identified a number of proteins on the BCG phagosomes that were not identified in any of our latex bead phagosome preparations, including proteins involved in membrane trafficking and signal transduction, such as Ras GTPase-activating-like protein IQGAP1, and proteins of unknown function, such as FAM3C. Our

  12. Identification of an immune-regulated phagosomal Rab cascade in macrophages

    PubMed Central

    Pei, Gang; Repnik, Urska; Griffiths, Gareth; Gutierrez, Maximiliano Gabriel

    2014-01-01

    ABSTRACT Interferon-γ (IFN-γ) has been shown to regulate phagosome trafficking and function in macrophages, but the molecular mechanisms involved are poorly understood. Here, we identify Rab20 as part of the machinery by which IFN-γ controls phagosome maturation. We found that IFN-γ stimulates the association of Rab20 with early phagosomes in macrophages. By using imaging of single phagosomes in live cells, we found that Rab20 induces an early delay in phagosome maturation and extends the time for which Rab5a and phosphatidylinositol 3-phosphate (PI3P) remain associated with phagosomes. Moreover, Rab20 depletion in macrophages abrogates the delay in phagosome maturation induced by IFN-γ. Finally, we demonstrate that Rab20 interacts with the Rab5a guanine nucleotide exchange factor Rabex-5 (also known as RABGEF1) and that Rab20 knockdown impairs the IFN-γ-dependent recruitment of Rabex-5 and Rab5a into phagosomes. Taken together, here, we uncover Rab20 as a key player in the Rab cascade by which IFN-γ induces a delay in phagosome maturation in macrophages. PMID:24569883

  13. Modulation of Phagosomal pH by Candida albicans Promotes Hyphal Morphogenesis and Requires Stp2p, a Regulator of Amino Acid Transport

    PubMed Central

    Vylkova, Slavena; Lorenz, Michael C.

    2014-01-01

    Candida albicans, the most important fungal pathogen of humans, has a unique interaction with macrophages in which phagocytosis induces a switch from the yeast to hyphal form, allowing it to escape by rupturing the immune cell. While a variety of factors induce this switch in vitro, including neutral pH, it is not clear what triggers morphogenesis within the macrophage where the acidic environment should inhibit this transition. In vitro, C. albicans grown in similar conditions in which amino acids are the primary carbon source generate large quantities of ammonia to raise the extracellular pH and induce the hyphal switch. We show here that C. albicans cells neutralize the macrophage phagosome and that neutral pH is a key inducer of germination in phagocytosed cells by using a mutant lacking STP2, a transcription factor that regulates the expression of multiple amino acid permeases, that is completely deficient in alkalinization in vitro. Phagocytosed stp2Δ mutant cells showed significant reduction in hypha formation and escaped from macrophages less readily compared to wild type cells; as a result stp2Δ mutant cells were killed at a higher rate and caused less damage to RAW264.7 macrophages. Stp2p-regulated import leads to alkalinization of the phagosome, since the majority of the wild type cells fail to co-localize with acidophilic dyes, whereas the stp2Δ mutant cells were located in acidic phagosomes. Furthermore, stp2Δ mutant cells were able to form hyphae and escape from neutral phagosomes, indicating that the survival defect in these cells was pH dependent. Finally, these defects are reflected in an attenuation of virulence in a mouse model of disseminated candidiasis. Altogether our results suggest that C. albicans utilizes amino acids to promote neutralization of the phagosomal pH, hyphal morphogenesis, and escape from macrophages. PMID:24626429

  14. The Tetrahymena thermophila phagosome proteome.

    PubMed

    Jacobs, Mary Ellen; DeSouza, Leroi V; Samaranayake, Haresha; Pearlman, Ronald E; Siu, K W Michael; Klobutcher, Lawrence A

    2006-12-01

    In vertebrates, phagocytosis occurs mainly in specialized cells of the immune system and serves as a primary defense against invading pathogens, but it also plays a role in clearing apoptotic cells and in tissue remodeling during development. In contrast, unicellular eukaryotes, such as the ciliate Tetrahymena thermophila, employ phagocytosis to ingest and degrade other microorganisms to meet their nutritional needs. To learn more about the protein components of the multistep process of phagocytosis, we carried out an analysis of the Tetrahymena phagosome proteome. Tetrahymena cells were fed polystyrene beads, which allowed for the efficient purification of phagosomes. The protein composition of purified phagosomes was then analyzed by multidimensional separation coupled with tandem mass spectrometry. A total of 453 peptides were identified that resulted in the identification of 73 putative phagosome proteins. Twenty-eight of the proteins have been implicated in phagocytosis in other organisms, indicating that key aspects of phagocytosis were conserved during evolution. Other identified proteins have not previously been associated with phagocytosis, including some of unknown function. Live-cell confocal fluorescence imaging of Tetrahymena strains expressing green fluorescent protein-tagged versions of four of the identified phagosome proteins provided evidence that at least three of the proteins (including two with unknown functions) are associated with phagosomes, indicating that the bulk of the proteins identified in the analyses are indeed phagosome associated.

  15. TRPC6 channel translocation into phagosomal membrane augments phagosomal function

    PubMed Central

    Riazanski, Vladimir; Gabdoulkhakova, Aida G.; Boynton, Lin S.; Eguchi, Raphael R.; Deriy, Ludmila V.; Hogarth, D. Kyle; Loaëc, Nadège; Oumata, Nassima; Galons, Hervé; Brown, Mary E.; Shevchenko, Pavel; Gallan, Alexander J.; Yoo, Sang Gune; Naren, Anjaparavanda P.; Villereal, Mitchel L.; Beacham, Daniel W.; Bindokas, Vytautas P.; Birnbaumer, Lutz; Meijer, Laurent; Nelson, Deborah J.

    2015-01-01

    Defects in the innate immune system in the lung with attendant bacterial infections contribute to lung tissue damage, respiratory insufficiency, and ultimately death in the pathogenesis of cystic fibrosis (CF). Professional phagocytes, including alveolar macrophages (AMs), have specialized pathways that ensure efficient killing of pathogens in phagosomes. Phagosomal acidification facilitates the optimal functioning of degradative enzymes, ultimately contributing to bacterial killing. Generation of low organellar pH is primarily driven by the V-ATPases, proton pumps that use cytoplasmic ATP to load H+ into the organelle. Critical to phagosomal acidification are various channels derived from the plasma membrane, including the anion channel cystic fibrosis transmembrane conductance regulator, which shunt the transmembrane potential generated by movement of protons. Here we show that the transient receptor potential canonical-6 (TRPC6) calcium-permeable channel in the AM also functions to shunt the transmembrane potential generated by proton pumping and is capable of restoring microbicidal function to compromised AMs in CF and enhancement of function in non-CF cells. TRPC6 channel activity is enhanced via translocation to the cell surface (and then ultimately to the phagosome during phagocytosis) in response to G-protein signaling activated by the small molecule (R)-roscovitine and its derivatives. These data show that enhancing vesicular insertion of the TRPC6 channel to the plasma membrane may represent a general mechanism for restoring phagosome activity in conditions, where it is lost or impaired. PMID:26604306

  16. Dynein Clusters into Lipid Microdomains on Phagosomes to Drive Rapid Transport toward Lysosomes

    PubMed Central

    Rai, Ashim; Pathak, Divya; Thakur, Shreyasi; Singh, Shampa; Dubey, Alok Kumar; Mallik, Roop

    2016-01-01

    Summary Diverse cellular processes are driven by motor proteins that are recruited to and generate force on lipid membranes. Surprisingly little is known about how membranes control the force from motors and how this may impact specific cellular functions. Here, we show that dynein motors physically cluster into microdomains on the membrane of a phagosome as it matures inside cells. Such geometrical reorganization allows many dyneins within a cluster to generate cooperative force on a single microtubule. This results in rapid directed transport of the phagosome toward microtubule minus ends, likely promoting phagolysosome fusion and pathogen degradation. We show that lipophosphoglycan, the major molecule implicated in immune evasion of Leishmania donovani, inhibits phagosome motion by disrupting the clustering and therefore the cooperative force generation of dynein. These findings appear relevant to several pathogens that prevent phagosome-lysosome fusion by targeting lipid microdomains on phagosomes. PMID:26853472

  17. Linking inflammasome activation and phagosome maturation.

    PubMed

    Lazarevic, Vanja; Martinon, Fabio

    2008-04-17

    One-third of the world's population is infected with Mycobacterium tuberculosis, one of the most effective human pathogens, whose success is attributed to the deployment of remarkably sophisticated immune evasion mechanisms. In this issue of Cell Host & Microbe, a new study unravels a novel strategy of immune evasion and enhanced bacterial intracellular survival, which is dependent on inhibition of inflammasome activation by an M. tuberculosis-encoded metalloprotease.

  18. Force dependence of phagosome trafficking in retinal pigment epithelial cells

    NASA Astrophysics Data System (ADS)

    Daniel, Rebekah; Koll, Andrew T.; Altman, David

    2014-09-01

    Retinal pigment epithelial (RPE) cells play an integral role in the renewal of photoreceptor disk membranes. As rod and cone cells shed their outer segments, they are phagocytosed and degraded by the RPE, and a failure in this process can result in retinal degeneration. We have studied the role of myosin VI in nonspecific phagocytosis in a human RPE primary cell line (ARPE-19), testing the hypothesis that this motor generates the forces required to traffic phagosomes in these cells. Experiments were conducted in the presence of forces through the use of in vivo optical trapping. Our results support a role for myosin VI in phagosome trafficking and demonstrate that applied forces modulate rates of phagosome trafficking.

  19. Isolation of Latex Bead Phagosomes from Dictyostelium for in vitro Functional Assays

    PubMed Central

    D’Souza, Ashwin; Sanghavi, Paulomi; Rai, Ashim; Pathak, Divya; Mallik, Roop

    2017-01-01

    We describe a protocol to purify latex bead phagosomes (LBPs) from Dictyostelium cells. These can be later used for various in vitro functional assays. For instance, we use these LBPs to understand the microtubule motor-driven transport on in vitro polymerized microtubules. Phagosomes are allowed to mature for defined periods inside cells before extraction for in vitro motility. These assays allow us to probe how lipids on the phagosome membrane recruit and organize motors, and also measure the motion and force generation resulting from underlying lipid-motor interactions. This provides a unique opportunity to interrogate native-like organelles using biophysical and biochemical assays, and understand the role of motor proteins in phagosome maturation and pathogen clearance. PMID:28239623

  20. Pathogenic Mycobacterium avium remodels the phagosome membrane in macrophages within days after infection.

    PubMed

    de Chastellier, Chantal; Thilo, Lutz

    2002-01-01

    As part of their strategy for intracellular survival, mycobacteria prevent maturation of the phagosomes in which they reside inside macrophages. The molecular basis for this inhibition is only now beginning to emerge, by way of the molecular characterisation of the phagosome membrane when it encloses virulent mycobacteria. Our own work has shown that at 15 days after the phagocytic uptake of Mycobacterium avium by mouse bone marrow-derived macrophages, the phagosome membrane is depleted about 4-fold for cell surface-derived membrane glycoconjugates, labelled by exogalactosylation, in comparison to the membrane of early endosomes with which it continues to interact. Here we asked whether this depletion occurred at early or late stages after infection. We found that only about half of the depletion had occurred at about 5 hours after the beginning of phagocytic uptake, with the remainder becoming established thereafter, with a half-time of about 2.5 days. Phagosomes became depleted in relation to early endosomes with which they continued to exchange membrane constituents. Early endosomes themselves became gradually depleted by about 30% during the 15-day post-infection period. In contrast, late endosomes/lysosomes remained unchanged, with a concentration of surface-derived glycoconjugates between that of early endosomes and of phagosomes at day 15 post infection. In view of the slowness of the post-infection change of phagosome membrane composition, we proposed that this change did not play a role in preventing maturation immediately after phagosome formation, but rather correlated with the process of maintaining the phagosomes in an immature state.

  1. Magnetic phagosome motion in J774A.1 macrophages: influence of cytoskeletal drugs.

    PubMed Central

    Möller, W; Nemoto, I; Matsuzaki, T; Hofer, T; Heyder, J

    2000-01-01

    mechanism is MF-associated. MT depolymerization by CoL induces an activation of the F-actin synthesis, which may induce an accelerated relaxation and an increase of stiffness. Cell mechanical properties are not modulated by MF depolymerization, whereas MT depolymerization causes a loss of viscous resistance and a loss of cell elasticity. The mean energy for stochastic phagosome transport is 5*10(-18) Joules and corresponds to a force of 7 pN on a single 1.3-microm phagosome. PMID:10920006

  2. Analysis of phagosomal proteomes: From latex-bead to bacterial phagosomes

    PubMed Central

    Li, Qingbo; Jagannath, Chinnaswamy; Rao, Prahlad K.; Singh, Christopher R.; Lostumbo, Giovanni

    2014-01-01

    Phagosomal proteome characterization has contributed significantly to the understanding of host–pathogen interaction and the mechanism of infectious diseases caused by intracellular bacteria. The latex bead-containing phagosome has been widely used as a model system to study phagosomal proteomes at a global level. In contrast, the study of bacteria-containing phagosomes at a similar level has just begun. A number of intracellular microbial species are studied for their proteomes during the invasion of a host, providing insight into their metabolic adaptation in host cells and interaction with host-cell antimicrobial environments. In this review, we attempt to summarize the most recent advancements in the proteomic study of microbial phagosomes, especially those originating from mouse or human cells. We also briefly describe the proteomics of latex bead-containing phagosomes because they are often used as model phagosomes for study. We provide descriptions on major biological and technological components in phagosomal proteome studies. We also discuss the role of phagosomal proteome study in the broader horizon of systems biology and the technological challenges in phagosomal proteome characterization. PMID:21080496

  3. Bacillus anthracis factors for phagosomal escape.

    PubMed

    Tonello, Fiorella; Zornetta, Irene

    2012-07-01

    The mechanism of phagosome escape by intracellular pathogens is an important step in the infectious cycle. During the establishment of anthrax, Bacillus anthracis undergoes a transient intracellular phase in which spores are engulfed by local phagocytes. Spores germinate inside phagosomes and grow to vegetative bacilli, which emerge from their resident intracellular compartments, replicate and eventually exit from the plasma membrane. During germination, B. anthracis secretes multiple factors that can help its resistance to the phagocytes. Here the possible role of B. anthracis toxins, phospholipases, antioxidant enzymes and capsules in the phagosomal escape and survival, is analyzed and compared with that of factors of other microbial pathogens involved in the same type of process.

  4. Intracellular Survival of Brucella spp. in Human Monocytes Involves Conventional Uptake but Special Phagosomes

    PubMed Central

    Rittig, Michael G.; Alvarez-Martinez, Maria-Teresa; Porte, Françoise; Liautard, Jean-Pierre; Rouot, Bruno

    2001-01-01

    Brucella spp. are facultative intracellular parasites of various mammals, including humans, typically infecting lymphoid as well as reproductive organs. We have investigated how B. suis and B. melitensis enter human monocytes and in which compartment they survive. Peripheral blood monocytes readily internalized nonopsonized brucellae and killed most of them within 12 to 18 h. The presence of Brucella-specific antibodies (but not complement) increased the uptake of bacteria without increasing their intracellular survival, whereas adherence of the monocytes or incubation in Ca2+- and Mg2+-free medium reduced the uptake. Engulfment of all Brucella organisms (regardless of bacterial viability or virulence) initially resulted in phagosomes with tightly apposed walls (TP). Most TP were fully fusiogenic and matured to spacious phagolysosomes containing degraded bacteria, whereas some TP (more in monocyte-derived macrophages, HeLa cells, and CHO cells than in monocytes) remained tightly apposed to intact bacteria. Immediate treatment of infected host cells with the lysosomotropic base ammonium chloride caused a swelling of all phagosomes and a rise in the intraphagosomal pH, abolishing the intracellular survival of Brucella. These results indicate that (i) human monocytes readily internalize Brucella in a conventional way using various phagocytosis-promoting receptors, (ii) the maturation of some Brucella phagosomes is passively arrested between the steps of acidification and phagosome-lysosome fusion, (iii) brucellae are killed in maturing but not in arrested phagosomes, and (iv) survival of internalized Brucella depends on an acidic intraphagosomal pH and/or close contact with the phagosomal wall. PMID:11349069

  5. Construction of chimeric phagosomes that shelter Mycobacterium avium and Coxiella burnetii (phase II) in doubly infected mouse macrophages: an ultrastructural study.

    PubMed

    de Chastellier, C; Thibon, M; Rabinovitch, M

    1999-08-01

    Dual infection of cells may divert pathogens to intracellular compartments different from those occupied in mono-infected cells. In the present studies, mouse bone marrow in vitro-derived macrophages were first infected with virulent Mycobacterium avium, which are normally singly lodged within tight phagosomes. These phagosomes do not mature; they undergo homotypic fusion with early endosomes and do not fuse with lysosomes. Seven days later, the cultures were superinfected with phase II (non-virulent) Coxiella burnetii, organisms sheltered in lysosome- (or prelysosome)-like, multi-occupancy phagosomes. The latter can attain large size and engage in efficient homo- and heterotypic fusion with other phagosomes. Cultures were fixed for transmission electron microscopy 6, 12, 24, and 48 h later. Other M. avium-infected cultures were superinfected with amastigotes of the trypanosomatid flagellate Leishmania amazonensis, which are also sheltered in lysosome- (or prelysosome)-like multi-occupancy vacuoles, and fixed at the same time periods. Chimeric phagosomes containing both M. avium and C. burnetii, were found already at 6 h and the proportion of M. avium that colocalized with C. burnetii in the same phagosomes reached over 90% after 48 h. In such phagosomes, both organisms were ultrastructurally well preserved. In contrast, colocalization of M. avium and L. amazonensis was rarely found. Speculative scenarios that could underlie the formation of chimeric phagosomes could involve delayed maturation of C. burnetii-containing phagosomes in presence of M. avium, which would allow for fusion of C. burnetii- and M. avium-containing phagosomes; the production, by C. burnetii, of molecules that upregulate the fusion of M. avium-containing phagosomes with those that contain C. burnetii; and the secretion of factors that could favour the survival of M. avium within chimeric vacuoles.

  6. Staphylococcus aureus Strain USA300 Perturbs Acquisition of Lysosomal Enzymes and Requires Phagosomal Acidification for Survival inside Macrophages

    PubMed Central

    Tranchemontagne, Zachary R.; Camire, Ryan B.; O'Donnell, Vanessa J.; Baugh, Jessfor

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) causes invasive, drug-resistant skin and soft tissue infections. Reports that S. aureus bacteria survive inside macrophages suggest that the intramacrophage environment may be a niche for persistent infection; however, mechanisms by which the bacteria might evade macrophage phagosomal defenses are unclear. We examined the fate of the S. aureus-containing phagosome in THP-1 macrophages by evaluating bacterial intracellular survival and phagosomal acidification and maturation and by testing the impact of phagosomal conditions on bacterial viability. Multiple strains of S. aureus survived inside macrophages, and in studies using the MRSA USA300 clone, the USA300-containing phagosome acidified rapidly and acquired the late endosome and lysosome protein LAMP1. However, fewer phagosomes containing live USA300 bacteria than those containing dead bacteria associated with the lysosomal hydrolases cathepsin D and β-glucuronidase. Inhibiting lysosomal hydrolase activity had no impact on intracellular survival of USA300 or other S. aureus strains, suggesting that S. aureus perturbs acquisition of lysosomal enzymes. We examined the impact of acidification on S. aureus intramacrophage viability and found that inhibitors of phagosomal acidification significantly impaired USA300 intracellular survival. Inhibition of macrophage phagosomal acidification resulted in a 30-fold reduction in USA300 expression of the staphylococcal virulence regulator agr but had little effect on expression of sarA, saeR, or sigB. Bacterial exposure to acidic pH in vitro increased agr expression. Together, these results suggest that S. aureus survives inside macrophages by perturbing normal phagolysosome formation and that USA300 may sense phagosomal conditions and upregulate expression of a key virulence regulator that enables its intracellular survival. PMID:26502911

  7. Molecular characterization of the evolution of phagosomes

    PubMed Central

    Boulais, Jonathan; Trost, Matthias; Landry, Christian R; Dieckmann, Régis; Levy, Emmanuel D; Soldati, Thierry; Michnick, Stephen W; Thibault, Pierre; Desjardins, Michel

    2010-01-01

    Amoeba use phagocytosis to internalize bacteria as a source of nutrients, whereas multicellular organisms utilize this process as a defense mechanism to kill microbes and, in vertebrates, initiate a sustained immune response. By using a large-scale approach to identify and compare the proteome and phosphoproteome of phagosomes isolated from distant organisms, and by comparative analysis over 39 taxa, we identified an ‘ancient' core of phagosomal proteins around which the immune functions of this organelle have likely organized. Our data indicate that a larger proportion of the phagosome proteome, compared with the whole cell proteome, has been acquired through gene duplication at a period coinciding with the emergence of innate and adaptive immunity. Our study also characterizes in detail the acquisition of novel proteins and the significant remodeling of the phagosome phosphoproteome that contributed to modify the core constituents of this organelle in evolution. Our work thus provides the first thorough analysis of the changes that enabled the transformation of the phagosome from a phagotrophic compartment into an organelle fully competent for antigen presentation. PMID:20959821

  8. Mycobacterium tuberculosis and Mycobacterium avium modify the composition of the phagosomal membrane in infected macrophages by selective depletion of cell surface-derived glycoconjugates.

    PubMed

    Pietersen, Raydean; Thilo, Lutz; de Chastellier, Chantal

    2004-05-01

    The growth of pathogenic mycobacteria in phagosomes of the host cell correlates with their ability to prevent phagosome maturation. The underlying molecular mechanism remains elusive. In a previous study, we have shown that Mycobacterium avium depletes the phagosome membrane of cell surface-derived glycoconjugates (de Chastellier and Thilo, Eur. J. Cell Biol. 81, 17-25, 2002). We now extended these quantitative observations to the major human pathogen, Mycobacterium tuberculosis (H37Rv). At increasing times after infection of mouse bone marrow-derived macrophages, cell-surface glycoconjugates were labelled enzymatically with [3H]galactose. Subsequent endocytic membrane traffic resulted in a redistribution of this label from the cell surface to endocytic membranes, including phagosomes. The steady-state distribution was measured by quantitative autoradiography at the electron microscope level. Relative to early endosomes, with which phagosomes continued to fuse and rapidly exchange membrane constituents, the phagosome membrane was depleted about 3-fold, starting during infection and in the course of 9 days thereafter. These results were in quantitative agreement with our previous observations for Mycobacterium avium. For the latter case, we now showed by cell fractionation that the depletion was selective, mainly involving glycoproteins in the 110-210 kDa range. Together, these results indicated that pathogenic mycobacteria induced and maintained a bulk change in phagosome membrane composition that could be of special relevance for survival of pathogenic mycobacteria within phagosomes.

  9. Chloride transport in functionally active phagosomes isolated from Human neutrophils

    PubMed Central

    Aiken, Martha L.; Painter, Richard G.; Zhou, Yun; Wang, Guoshun

    2012-01-01

    Chloride anion is critical for hypochlorous acid (HOCl) production and microbial killing in neutrophil phagosomes. However, the molecular mechanism by which this anion is transported to the organelle is poorly understood. In this report, membrane-enclosed and functionally active phagosomes were isolated from human neutrophils by using opsonized paramagnetic latex microspheres and a rapid magnetic separation method. The phagosomes recovered were highly enriched for specific protein markers associated with this organelle such as lysosomal-associated membrane protein-1, myeloperoxidase (MPO), lactoferrin, and NADPH oxidase. When FITC–dextran was included in the phagocytosis medium, the majority of the isolated phagosomes retained the fluorescent label after isolation, indicative of intact membrane structure. Flow cytometric measurement of acridine orange, a fluorescent pH indicator, in the purified phagosomes demonstrated that the organelle in its isolated state was capable of transporting protons to the phagosomal lumen via the vacuolar-type ATPase proton pump (V-ATPase). When NADPH was supplied, the isolated phagosomes constitutively oxidized dihydrorhodamine 123, indicating their ability to produce hydrogen peroxide. The preparations also showed a robust production of HOCl within the phagosomal lumen when assayed with the HOCl-specific fluorescent probe R19-S by flow cytometry. MPO-mediated iodination of the proteins covalently conjugated to the phagocytosed beads was quantitatively measured. Phagosomal uptake of iodide and protein iodination were significantly blocked by chloride channel inhibitors, including CFTRinh-172 and NPPB. Further experiments determined that the V-ATPase-driving proton flux into the isolated phagosomes required chloride cotransport, and the cAMP-activated CFTR chloride channel was a major contributor to the chloride transport. Taken together, the data suggest that the phagosomal preparation described herein retains ion transport

  10. Link between intraphagosomal biotin and rapid phagosomal escape in Francisella

    PubMed Central

    Napier, Brooke A.; Meyer, Lena; Bina, James E.; Miller, Mark A.; Sjöstedt, Anders; Weiss, David S.

    2012-01-01

    Cytosolic bacterial pathogens require extensive metabolic adaptations within the host to replicate intracellularly and cause disease. In phagocytic cells such as macrophages, these pathogens must respond rapidly to nutrient limitation within the harsh environment of the phagosome. Many cytosolic pathogens escape the phagosome quickly (15–60 min) and thereby subvert this host defense, reaching the cytosol where they can replicate. Although a great deal of research has focused on strategies used by bacteria to resist antimicrobial phagosomal defenses and transiently pass through this compartment, the metabolic requirements of bacteria in the phagosome are largely uncharacterized. We previously identified a Francisella protein, FTN_0818, as being essential for intracellular replication and involved in virulence in vivo. We now show that FTN_0818 is involved in biotin biosynthesis and required for rapid escape from the Francisella-containing phagosome (FCP). Addition of biotin complemented the phagosomal escape defect of the FTN_0818 mutant, demonstrating that biotin is critical for promoting rapid escape during the short time that the bacteria are in the phagosome. Biotin also rescued the attenuation of the FTN_0818 mutant during infection in vitro and in vivo, highlighting the importance of this process. The key role of biotin in phagosomal escape implies biotin may be a limiting factor during infection. We demonstrate that a bacterial metabolite is required for phagosomal escape of an intracellular pathogen, providing insight into the link between bacterial metabolism and virulence, likely serving as a paradigm for other cytosolic pathogens. PMID:23071317

  11. ARTICULAR CARTILAGE TENSILE INTEGRITY: MODULATION BY MATRIX DEPLETION IS MATURATION-DEPENDENT

    PubMed Central

    Asanbaeva, Anna; Tam, Johnny; Schumacher, Barbara L.; Klisch, Stephen M.; Masuda, Koichi; Sah, Robert L.

    2008-01-01

    Articular cartilage function depends on the molecular composition and structure of its extracellular matrix (ECM). The collagen network (CN) provides cartilage with tensile integrity, but must also remodel during growth. Such remodeling may depend on matrix molecules interacting with the CN to modulate the tensile behavior of cartilage. The objective of this study was to determine the effects of increasingly selective matrix depletion on tensile properties of immature and mature articular cartilage, and thereby establish a framework for identifying molecules involved in CN remodeling. Depletion of immature cartilage with guanidine, chondroitinase ABC, chondroitinase AC, and Streptomyces hyaluronidase markedly increased tensile integrity, while the integrity of mature cartilage remained unaltered after depletion with guanidine. The enhanced tensile integrity after matrix depletion suggests that certain ECM components of immature matrix serve to inhibit CN interactions and may act as modulators of physiological alterations of cartilage geometry and tensile properties during growth/maturation. PMID:18394422

  12. Phagosomes Induced by Cytokines Function as anti-Listeria Vaccines

    PubMed Central

    Carrasco-Marín, Eugenio; Rodriguez-Del Rio, Estela; Frande-Cabanes, Elisabet; Tobes, Raquel; Pareja, Eduardo; Lecea-Cuello, M. Jesús; Ruiz-Sáez, Marta; Madrazo-Toca, Fidel; Hölscher, Christoph; Alvarez-Dominguez, Carmen

    2012-01-01

    Phagosomes are critical compartments for innate immunity. However, their role in the protection against murine listeriosis has not been examined. We describe here that listericidal phago-receptosomes are induced by the function of IFN-γ or IL-6 as centralized compartments for innate and adaptive immunity because they are able to confer protection against murine listeriosis. These phago-receptosomes elicited LLO(91–99)/CD8+- and LLO(189–201)/CD4+-specific immune responses and recruited mature dendritic cells to the vaccination sites controlled by T cells. Moreover, they present exceptional features as efficient vaccine vectors. First, they compartmentalize a novel listericidal STAT-1-mediated signaling pathway that confines multiple innate immune components to the same environment. Second, they show features of MHC class II antigen-loading competent compartments for cathepsin-D-mediated LLO processing. Third, murine cathepsin-D deficiencies fail to develop protective immunity after vaccination with listericidal phago-receptosomes induced by IFN-γ or IL-6. Therefore, it appears that the connection of STAT-1 and cathepsin-D in a single compartment is relevant for protection against listeriosis. PMID:22337873

  13. Mechanically Induced Actin-mediated Rocketing of Phagosomes

    PubMed Central

    Müller-Taubenberger, Annette; Anderson, Kurt I.; Engel, Ulrike; Gerisch, Günther

    2006-01-01

    Actin polymerization can be induced in Dictyostelium by compressing the cells to bring phagosomes filled with large particles into contact with the plasma membrane. Asymmetric actin assembly results in rocketing movement of the phagosomes. We show that the compression-induced assembly of actin at the cytoplasmic face of the plasma membrane involves the Arp2/3 complex. We also identify two other proteins associated with the mechanically induced actin assembly. The class I myosin MyoB accumulates at the plasma membrane–phagosome interface early during the initiation of the response, and coronin is recruited as the actin filaments are disassembling. The forces generated by rocketing phagosomes are sufficient to push the entire microtubule apparatus forward and to dislocate the nucleus. PMID:16971511

  14. Oxidized phagosomal NOX2 is replenished from lysosomes.

    PubMed

    Dingjan, Ilse; Linders, Peter T A; van den Bekerom, Luuk; Baranov, Maksim V; Halder, Partho; Ter Beest, Martin; van den Bogaart, Geert

    2017-02-15

    In dendritic cells, the NADPH oxidase 2 (NOX2) is recruited to the phagosomal membrane during antigen uptake. NOX2 produces reactive oxygen species (ROS) in the lumen of the phagosome which kill ingested pathogens, delay antigen breakdown and alter the peptide repertoire for presentation to T cells. How the integral membrane component of NOX2, cytochrome b558, traffics to phagosomes is incompletely understood. In this study, we show in dendritic cells derived from human blood-isolated monocytes that cytochrome b558 is initially recruited to the phagosome from the plasma membrane during phagosome formation. Cytochrome b558 also traffics from a lysosomal pool to phagosomes and this is required to replenish oxidatively damaged NOX2. We identified syntaxin-7, SNAP23 and VAMP8 as the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins mediating this process. Our data describe a key mechanism of how dendritic cells sustain ROS production after antigen uptake required to initiate T cell responses.

  15. Catalase activity is modulated by calcium and calmodulin in detached mature leaves of sweet potato.

    PubMed

    Afiyanti, Mufidah; Chen, Hsien-Jung

    2014-01-15

    Catalase (CAT) functions as one of the key enzymes in the scavenging of reactive oxygen species and affects the H2O2 homeostasis in plants. In sweet potato, a major catalase isoform was detected, and total catalase activity showed the highest level in mature leaves (L3) compared to immature (L1) and completely yellow, senescent leaves (L5). The major catalase isoform as well as total enzymatic activity were strongly suppressed by ethylene glycol-bis(2-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA). This inhibition could be specifically and significantly mitigated in mature L3 leaves by exogenous CaCl2, but not MgCl2 or CoCl2. EGTA also inhibited the activity of the catalase isoform in vitro. Furthermore, chlorpromazine (CPZ), a calmodulin (CAM) inhibitor, drastically suppressed the major catalase isoform as well as total enzymatic activity, and this suppression was alleviated by exogenous sweet potato calmodulin (SPCAM) fusion protein in L3 leaves. CPZ also inhibited the activity of the catalase isoform in vitro. Protein blot hybridization showed that both anti-catalase SPCAT1 and anti-calmodulin SPCAM antibodies detect a band at the same position, which corresponds to the activity of the major catalase isoform from unboiled, but not boiled crude protein extract of L3 leaves. An inverse correlation between the major catalase isoform/total enzymatic activity and the H2O2 level was also observed. These data suggest that sweet potato CAT activity is modulated by CaCl2 and SPCAM, and plays an important role in H2O2 homeostasis in mature leaves. Association of SPCAM with the major CAT isoform is required and regulates the in-gel CAT activity band.

  16. Structural basis of substrate recognition by a bacterial deubiquitinase important for dynamics of phagosome ubiquitination

    PubMed Central

    Sheedlo, Michael J.; Qiu, Jiazhang; Tan, Yunhao; Paul, Lake N.; Luo, Zhao-Qing; Das, Chittaranjan

    2015-01-01

    Manipulation of the host’s ubiquitin network is emerging as an important strategy for counteracting and repurposing the posttranslational modification machineries of the host by pathogens. Ubiquitin E3 ligases encoded by infectious agents are well known, as are a variety of viral deubiquitinases (DUBs). Bacterial DUBs have been discovered, but little is known about the structure and mechanism underlying their ubiquitin recognition. In this report, we found that members of the Legionella pneumophila SidE effector family harbor a DUB module important for ubiquitin dynamics on the bacterial phagosome. Structural analysis of this domain alone and in complex with ubiquitin vinyl methyl ester (Ub-VME) reveals unique molecular contacts used in ubiquitin recognition. Instead of relying on the Ile44 patch of ubiquitin, as commonly used in eukaryotic counterparts, the SdeADub module engages Gln40 of ubiquitin. The architecture of the active-site cleft presents an open arrangement with conformational plasticity, permitting deubiquitination of three of the most abundant polyubiquitin chains, with a distinct preference for Lys63 linkages. We have shown that this preference enables efficient removal of Lys63 linkages from the phagosomal surface. Remarkably, the structure reveals by far the most parsimonious use of molecular contacts to achieve deubiquitination, with less than 1,000 Å2 of accessible surface area buried upon complex formation with ubiquitin. This type of molecular recognition appears to enable dual specificity toward ubiquitin and the ubiquitin-like modifier NEDD8. PMID:26598703

  17. CD4+ T Cells: guardians of the phagosome.

    PubMed

    Tubo, Noah J; Jenkins, Marc K

    2014-04-01

    CD4(+) T cells are key cells of the adaptive immune system that use T cell antigen receptors to recognize peptides that are generated in endosomes or phagosomes and displayed on the host cell surface bound to major histocompatibility complex molecules. These T cells participate in immune responses that protect hosts from microbes such as Mycobacterium tuberculosis, Cryptococcus neoformans, Leishmania major, and Salmonella enterica, which have evolved to live in the phagosomes of macrophages and dendritic cells. Here, we review studies indicating that CD4(+) T cells control phagosomal infections asymptomatically in most individuals by secreting cytokines that activate the microbicidal activities of infected phagocytes but in a way that inhibits the pathogen but does not eliminate it. Indeed, we make the case that localized, controlled, persistent infection is necessary to maintain large numbers of CD4(+) effector T cells in a state of activation needed to eradicate systemic and more pathogenic forms of the infection. Finally, we posit that current vaccines for phagosomal infections fail because they do not produce this "periodic reminder" form of CD4(+) T cell-mediated immune control.

  18. Phosphoinositol 3-phosphate acts as a timer for reactive oxygen species production in the phagosome.

    PubMed

    Song, Zhi Min; Bouchab, Leïla; Hudik, Elodie; Le Bars, Romain; Nüsse, Oliver; Dupré-Crochet, Sophie

    2017-01-17

    Production of reactive oxygen species (ROS) in the phagosome by the NADPH oxidase is critical for mammalian immune defense against microbial infections and phosphoinositides are important regulators in this process. Phosphoinositol 3-phosphate (PI(3)P) regulates ROS production at the phagosome via p40(phox) by an unknown mechanism. This study tested the hypothesis that PI(3)P controls ROS production by regulating the presence of p40(phox) and p67(phox) at the phagosomal membrane. Pharmacologic inhibition of PI(3)P synthesis at the phagosome decreased the ROS production both in differentiated PLB-985 cells and human neutrophils. It also releases p67(phox), the key cytosolic subunit of the oxidase, and p40(phox) from the phagosome. The knockdown of the PI(3)P phosphatase MTM1 or Rubicon or both increases the level of PI(3)P at the phagosome. That increase enhances ROS production inside the phagosome and triggers an extended accumulation of p67(phox) at the phagosome. Furthermore, the overexpression of MTM1 at the phagosomal membrane induces the disappearance of PI(3)P from the phagosome and prevents sustained ROS production. In conclusion, PI(3)P, indeed, regulates ROS production by maintaining p40(phox) and p67(phox) at the phagosomal membrane.

  19. A Novel, Noncanonical BMP Pathway Modulates Synapse Maturation at the Drosophila Neuromuscular Junction

    PubMed Central

    Sulkowski, Mikolaj J.; Han, Tae Hee; Ott, Carolyn; Wang, Qi; Verheyen, Esther M.; Lippincott-Schwartz, Jennifer; Serpe, Mihaela

    2016-01-01

    At the Drosophila NMJ, BMP signaling is critical for synapse growth and homeostasis. Signaling by the BMP7 homolog, Gbb, in motor neurons triggers a canonical pathway—which modulates transcription of BMP target genes, and a noncanonical pathway—which connects local BMP/BMP receptor complexes with the cytoskeleton. Here we describe a novel noncanonical BMP pathway characterized by the accumulation of the pathway effector, the phosphorylated Smad (pMad), at synaptic sites. Using genetic epistasis, histology, super resolution microscopy, and electrophysiology approaches we demonstrate that this novel pathway is genetically distinguishable from all other known BMP signaling cascades. This novel pathway does not require Gbb, but depends on presynaptic BMP receptors and specific postsynaptic glutamate receptor subtypes, the type-A receptors. Synaptic pMad is coordinated to BMP’s role in the transcriptional control of target genes by shared pathway components, but it has no role in the regulation of NMJ growth. Instead, selective disruption of presynaptic pMad accumulation reduces the postsynaptic levels of type-A receptors, revealing a positive feedback loop which appears to function to stabilize active type-A receptors at synaptic sites. Thus, BMP pathway may monitor synapse activity then function to adjust synapse growth and maturation during development. PMID:26815659

  20. Mature neurons modulate neurogenesis through chemical signals acting on neural stem cells.

    PubMed

    Pardal, Ricardo; López Barneo, José

    2016-06-01

    The discovery of neural stem cells has revealed a much higher structural and functional plasticity in the adult nervous system than previously anticipated. Progenitor cells are able to give rise to new neurons and glial cells when needed, thanks to their surveillance of the environment from the germinal niches. Multiple different factors define neural stem cell niches, including cellular and non-cellular components. Innervation of neurogenic centers is crucial, as it allows the functional connection between stem cell behavior and surrounding neuronal activity. Although the association between organismal behavior and neurogenesis is well documented, much less is known about the cellular and molecular mechanisms by which neurons control stem cell activity. In this review we discuss the existing data on this type of regulation from the three best characterized germinal niches in the adult nervous system: the subventricular zone, the hippocampal subgranular zone, and the carotid body. In all cases, neuronal activity modulates stem cell behavior either by neurotransmitter spillover or by synaptic-like contacts. Currently, the molecular mechanisms underlying mature neuron-stem cell interaction are being clarified. Functional consequences and potential clinical relevance of these phenomena are also discussed.

  1. An improved flow cytometry assay to monitor phagosome acidification.

    PubMed

    Colas, Chloé; Menezes, Shinelle; Gutiérrez-Martínez, Enric; Péan, Claire B; Dionne, Marc S; Guermonprez, Pierre

    2014-10-01

    Phago-lysosome formation is important for cell-autonomous immunity to intracellular pathogens, antigen presentation and metabolism. A hallmark feature of phago-lysosomal compartments is that they undergo progressive luminal acidification controlled by the activation of vacuolar V-ATPase. Acidification is required for many enzymatic processes taking place in phago-lysosomes, like proteolysis, and supports the microbicidal activity of macrophages. Here we present a new quantitative methodology to assess phagosome acidification by flow cytometry based on the use of bi-fluorescent particles. This method relies on the use of UV polystyrene beads labelled with the acid sensor pHrodo-succinimidyl ester (pHrodo(TM) SE red) and enables us to dissociate particle association with phagocytes from their engulfment in acidified compartments. This methodology is well suited to monitor the acidification of phagosomes formed in vivo after fluorescent bead administration.

  2. Voltage-gated proton channel is expressed on phagosomes

    SciTech Connect

    Okochi, Yoshifumi; Sasaki, Mari; Iwasaki, Hirohide; Okamura, Yasushi

    2009-05-01

    Voltage-gated proton channel has been suggested to help NADPH oxidase activity during respiratory burst of phagocytes through its activities of compensating charge imbalance and regulation of pH. In phagocytes, robust production of reactive oxygen species occurs in closed membrane compartments, which are called phagosomes. However, direct evidence for the presence of voltage-gated proton channels in phagosome has been lacking. In this study, the expression of voltage-gated proton channels was studied by Western blot with the antibody specific to the voltage-sensor domain protein, VSOP/Hv1, that has recently been identified as the molecular correlate for the voltage-gated proton channel. Phagosomal membranes of neutrophils contain VSOP/Hv1 in accordance with subunits of NADPH oxidases, gp91, p22, p47 and p67. Superoxide anion production upon PMA activation was significantly reduced in neutrophils from VSOP/Hv1 knockout mice. These are consistent with the idea that voltage-gated proton channels help NADPH oxidase in phagocytes to produce reactive oxygen species.

  3. Regulation of fatty acid oxidation in mouse cumulus-oocyte complexes during maturation and modulation by PPAR agonists.

    PubMed

    Dunning, Kylie R; Anastasi, Marie R; Zhang, Voueleng J; Russell, Darryl L; Robker, Rebecca L

    2014-01-01

    Fatty acid oxidation is an important energy source for the oocyte; however, little is known about how this metabolic pathway is regulated in cumulus-oocyte complexes. Analysis of genes involved in fatty acid oxidation showed that many are regulated by the luteinizing hormone surge during in vivo maturation, including acyl-CoA synthetases, carnitine transporters, acyl-CoA dehydrogenases and acetyl-CoA transferase, but that many are dysregulated when cumulus-oocyte complexes are matured under in vitro maturation conditions using follicle stimulating hormone and epidermal growth factor. Fatty acid oxidation, measured as production of ³H₂O from [³H]palmitic acid, occurs in mouse cumulus-oocyte complexes in response to the luteinizing hormone surge but is significantly reduced in cumulus-oocyte complexes matured in vitro. Thus we sought to determine whether fatty acid oxidation in cumulus-oocyte complexes could be modulated during in vitro maturation by lipid metabolism regulators, namely peroxisome proliferator activated receptor (PPAR) agonists bezafibrate and rosiglitazone. Bezafibrate showed no effect with increasing dose, while rosiglitazone dose dependently inhibited fatty acid oxidation in cumulus-oocyte complexes during in vitro maturation. To determine the impact of rosiglitazone on oocyte developmental competence, cumulus-oocyte complexes were treated with rosiglitazone during in vitro maturation and gene expression, oocyte mitochondrial activity and embryo development following in vitro fertilization were assessed. Rosiglitazone restored Acsl1, Cpt1b and Acaa2 levels in cumulus-oocyte complexes and increased oocyte mitochondrial membrane potential yet resulted in significantly fewer embryos reaching the morula and hatching blastocyst stages. Thus fatty acid oxidation is increased in cumulus-oocyte complexes matured in vivo and deficient during in vitro maturation, a known model of poor oocyte quality. That rosiglitazone further decreased fatty acid

  4. cAMP modulation during sheep in vitro oocyte maturation delays progression of meiosis without affecting oocyte parthenogenetic developmental competence.

    PubMed

    Buell, Margaret; Chitwood, James L; Ross, Pablo J

    2015-03-01

    Removal of oocytes from their natural inhibitory follicular environment results in spontaneous resumption of meiosis independent of normal signaling events that occur in vivo. Controlling the onset of meiotic resumption via maintenance of elevated oocyte cAMP levels with adenylyl cyclase (AC) activation and phosphodiesterase (PDE) inhibition, and subsequent hormone stimulation with follicle FSH has been shown to dramatically improve developmental competence of bovine and murine IVM oocytes. This study evaluated the effect of cAMP modulation during IVM of sheep oocytes on meiotic progression and development to blastocyst after parthenogenetic activation. Changes in oocyte cAMP levels were quantified during the first 2h of in vitro maturation in control or cAMP-modulating medium. No significant changes in intra-oocyte cAMP were observed under control conditions, though a slight and transient drop was noticed at 15 min of maturation. Addition of the AC stimulator Forskolin and the PDE inhibitors IBMX altered the cAMP profile, resulting in 10-fold elevation of cAMP by 15 min and sustained >3-fold elevated levels from 30 to 120 min. The effect of cAMP elevation on meiotic resumption was measured by completion of germinal vesicle breakdown. Modulated oocytes were significantly delayed when compared to control media oocytes. Also, progression to MII was significantly delayed in modulated versus control oocytes at 20 and 24h, though no differences persisted to 28 h. Lastly, when control and modulated oocytes were parthenogenetically activated, no differences in blastocyst formation were observed. Thus, while cAMP modulation delayed meiotic progression, it did not improve developmental competence of sheep IVM oocytes.

  5. MALDI mass spectrometry reveals that cumulus cells modulate the lipid profile of in vitro-matured bovine oocytes.

    PubMed

    Vireque, Alessandra A; Tata, Alessandra; Belaz, Katia Roberta A; Grázia, João Gabriel V; Santos, Fábio N; Arnold, Daniel R; Basso, Andrea C; Eberlin, Marcos N; Silva-de-Sá, Marcos Felipe; Ferriani, Rui A; Sá Rosa-E-Silva, Ana Carolina J

    2017-04-01

    The influence of cumulus cells (CC) on the lipid profile of bovine oocytes matured in two different lipid sources was investigated. Cumulus-oocyte complexes (COC) or denuded oocytes (DO) were matured in tissue culture medium (TCM) supplemented with fetal bovine serum (FBS) or serum substitute supplement (SSS). Lipid profiles of TCM, serum supplements, immature CC and oocyte (IO), and in vitro-matured oocytes from COC and DO were then analyzed by matrix assisted laser desorption ionization mass spectrometry (MALDI-MS) and submitted to partial least squares-discriminant analysis (PLS-DA). The developmental competence of such oocytes was also assessed. Differences in lipid composition were observed between two types of sera and distinctly influenced the lipid profile of CC. As revealed by PLS-DA, the abundance of specific ions corresponding to triacylglycerols (TAG) or phospholipids (PL) were higher in COC compared to DO both supplemented with FBS or SSS and to some extent affected the subsequent DO in vitro embryo development. DO exposed to SSS had however a marked diminished ability to develop to the blastocyst stage. These results indicate a modulation by CC of the oocyte TAG and PL profiles associated with a specific cell response to the serum supplement used for in vitro maturation.

  6. Measuring Phagosomal pH by Fluorescence Microscopy.

    PubMed

    Canton, Johnathan; Grinstein, Sergio

    2017-01-01

    Dual wavelength ratiometric imaging has become a powerful tool for the study of pH in intracellular compartments. It allows for the dynamic imaging of live cells while accounting for changes in the focal plane, differential loading of the fluorescent probe, and photobleaching caused by repeated image acquisitions. Ratiometric microscopic imaging has the added advantage over whole population methods of being able to resolve individual cells and even individual organelles. In this chapter we provide a detailed discussion of the basic principles of ratiometric imaging and its application to the measurement of phagosomal pH, including probe selection, the necessary instrumentation, and calibration methods.

  7. Junctate boosts phagocytosis by recruiting endoplasmic reticulum Ca2+ stores near phagosomes.

    PubMed

    Guido, Daniele; Demaurex, Nicolas; Nunes, Paula

    2015-11-15

    Local intracellular Ca(2+) elevations increase the efficiency of phagocytosis, a process that is essential for innate and adaptive immunity. These local Ca(2+) elevations are generated in part by the store-operated Ca(2+) entry (SOCE) sensor STIM1, which recruits endoplasmic reticulum (ER) cisternae to phagosomes and opens phagosomal Ca(2+) channels at ER-phagosome junctions. However, residual ER-phagosome contacts and periphagosomal Ca(2+) hotspots remain in Stim1(-/-) cells. Here, we tested whether junctate (also called ASPH isoform 8), a molecule that targets STIM1 to ER-plasma-membrane contacts upon Ca(2+)-store depletion, cooperates with STIM1 at phagosome junctions. Junctate expression in Stim1(-/-) and Stim1(-/-); Stim2(-/-) phagocytic fibroblasts increased phagocytosis and periphagosomal Ca(2+) elevations, yet with only a minimal impact on global SOCE. These Ca(2+) hotspots were only marginally reduced by the SOCE channel blocker lanthanum chloride (La(3+)) but were abrogated by inositol trisphosphate receptor inhibitors 2-APB and xestospongin-C, revealing that unlike STIM1-mediated hotspots, junctate-mediated Ca(2+) originates predominantly from periphagosomal Ca(2+) stores. Accordingly, junctate accumulates near phagosomes and elongates ER-phagosome junctions in Stim1(-/-) cells. Thus, junctate mediates an alternative mechanism for generating localized Ca(2+) elevations within cells, promoting Ca(2+) release from internal stores recruited to phagosomes, thereby boosting phagocytosis.

  8. Glycans from Fasciola hepatica Modulate the Host Immune Response and TLR-Induced Maturation of Dendritic Cells

    PubMed Central

    Rodríguez, Ernesto; Noya, Verónica; Cervi, Laura; Chiribao, María Laura; Brossard, Natalie; Chiale, Carolina; Carmona, Carlos; Giacomini, Cecilia; Freire, Teresa

    2015-01-01

    Helminths express various carbohydrate-containing glycoconjugates on their surface, and they release glycan-rich excretion/secretion products that can be very important in their life cycles, infection and pathology. Recent evidence suggests that parasite glycoconjugates could play a role in the evasion of the immune response, leading to a modified Th2-polarized immune response that favors parasite survival in the host. Nevertheless, there is limited information about the nature or function of glycans produced by the trematode Fasciola hepatica, the causative agent of fasciolosis. In this paper, we investigate whether glycosylated molecules from F. hepatica participate in the modulation of host immunity. We also focus on dendritic cells, since they are an important target of immune-modulation by helminths, affecting their activity or function. Our results indicate that glycans from F. hepatica promote the production of IL-4 and IL-10, suppressing IFNγ production. During infection, this parasite is able to induce a semi-mature phenotype of DCs expressing low levels of MHCII and secrete IL-10. Furthermore, we show that parasite glycoconjugates mediate the modulation of LPS-induced maturation of DCs since their oxidation restores the capacity of LPS-treated DCs to secrete high levels of the pro-inflammatory cytokines IL-6 and IL-12/23p40 and low levels of the anti-inflammatory cytokine IL-10. Inhibition assays using carbohydrates suggest that the immune-modulation is mediated, at least in part, by the recognition of a mannose specific-CLR that signals by recruiting the phosphatase Php2. The results presented here contribute to the understanding of the role of parasite glycosylated molecules in the modulation of the host immunity and might be useful in the design of vaccines against fasciolosis. PMID:26720149

  9. Glycans from Fasciola hepatica Modulate the Host Immune Response and TLR-Induced Maturation of Dendritic Cells.

    PubMed

    Rodríguez, Ernesto; Noya, Verónica; Cervi, Laura; Chiribao, María Laura; Brossard, Natalie; Chiale, Carolina; Carmona, Carlos; Giacomini, Cecilia; Freire, Teresa

    2015-12-01

    Helminths express various carbohydrate-containing glycoconjugates on their surface, and they release glycan-rich excretion/secretion products that can be very important in their life cycles, infection and pathology. Recent evidence suggests that parasite glycoconjugates could play a role in the evasion of the immune response, leading to a modified Th2-polarized immune response that favors parasite survival in the host. Nevertheless, there is limited information about the nature or function of glycans produced by the trematode Fasciola hepatica, the causative agent of fasciolosis. In this paper, we investigate whether glycosylated molecules from F. hepatica participate in the modulation of host immunity. We also focus on dendritic cells, since they are an important target of immune-modulation by helminths, affecting their activity or function. Our results indicate that glycans from F. hepatica promote the production of IL-4 and IL-10, suppressing IFNγ production. During infection, this parasite is able to induce a semi-mature phenotype of DCs expressing low levels of MHCII and secrete IL-10. Furthermore, we show that parasite glycoconjugates mediate the modulation of LPS-induced maturation of DCs since their oxidation restores the capacity of LPS-treated DCs to secrete high levels of the pro-inflammatory cytokines IL-6 and IL-12/23p40 and low levels of the anti-inflammatory cytokine IL-10. Inhibition assays using carbohydrates suggest that the immune-modulation is mediated, at least in part, by the recognition of a mannose specific-CLR that signals by recruiting the phosphatase Php2. The results presented here contribute to the understanding of the role of parasite glycosylated molecules in the modulation of the host immunity and might be useful in the design of vaccines against fasciolosis.

  10. Modulation of oligodendrocyte differentiation and maturation by combined biochemical and mechanical cues

    PubMed Central

    Lourenço, Tânia; Paes de Faria, Joana; Bippes, Christian A.; Maia, João; Lopes-da-Silva, José A.; Relvas, João B.; Grãos, Mário

    2016-01-01

    Extracellular matrix (ECM) proteins play a key role during oligodendrogenesis. While fibronectin (FN) is involved in the maintenance and proliferation of oligodendrocyte progenitor cells (OPCs), merosin (MN) promotes differentiation into oligodendrocytes (OLs). Mechanical properties of the ECM also seem to affect OL differentiation, hence this study aimed to clarify the impact of combined biophysical and biochemical elements during oligodendrocyte differentiation and maturation using synthetic elastic polymeric ECM-like substrates. CG-4 cells presented OPC- or OL-like morphology in response to brain-compliant substrates functionalised with FN or MN, respectively. The expression of the differentiation and maturation markers myelin basic protein — MBP — and proteolipid protein — PLP — (respectively) by primary rat oligodendrocytes was enhanced in presence of MN, but only on brain-compliant conditions, considering the distribution (MBP) or amount (PLP) of the protein. It was also observed that maturation of OLs was attained earlier (by assessing PLP expression) by cells differentiated on MN-functionalised brain-compliant substrates than on standard culture conditions. Moreover, the combination of MN and substrate compliance enhanced the maturation and morphological complexity of OLs. Considering the distinct degrees of stiffness tested ranging within those of the central nervous system, our results indicate that 6.5 kPa is the most suitable rigidity for oligodendrocyte differentiation. PMID:26879561

  11. Opa+ Neisseria gonorrhoeae Exhibits Reduced Survival in Human Neutrophils Via Src Family Kinase-Mediated Bacterial Trafficking Into Mature Phagolysosomes

    PubMed Central

    Johnson, M. Brittany; Ball, Louise M.; Daily, Kylene P.; Martin, Jennifer N.; Columbus, Linda; Criss, Alison K.

    2015-01-01

    Summary During gonorrheal infection, there is a heterogeneous population of Neisseria gonorrhoeae (Gc) varied in their expression of opacity-associated (Opa) proteins. While Opa proteins are important for bacterial attachment and invasion of epithelial cells, Opa+ Gc has a survival defect after exposure to neutrophils. Here, we use constitutively Opa- and OpaD+ Gc in strain background FA1090 to show that Opa+ Gc is more sensitive to killing inside adherent, chemokine-treated primary human neutrophils due to increased bacterial residence in mature, degradative phagolysosomes that contain primary and secondary granule antimicrobial content. Although Opa+ Gc stimulates a potent oxidative burst, neutrophil killing of Opa+ Gc was instead attributable to non-oxidative components, particularly neutrophil proteases and the bactericidal/permeability-increasing protein. Blocking interaction of Opa+ Gc with carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) or inhibiting Src family kinase signaling, which is downstream of CEACAM activation, enhanced the survival of Opa+ Gc in neutrophils. Src family kinase signaling was required for fusion of Gc phagosomes with primary granules to generate mature phagolysosomes. Conversely, ectopic activation of Src family kinases or coinfection with Opa+ Gc resulted in decreased survival of Opa- Gc in neutrophils. From these results, we conclude that Opa protein expression is an important modulator of Gc survival characteristics in neutrophils by influencing phagosome dynamics and thus bacterial exposure to neutrophils’ full antimicrobial arsenal. PMID:25346239

  12. Kaposi's sarcoma-associated herpesvirus K7 modulates Rubicon-mediated inhibition of autophagosome maturation.

    PubMed

    Liang, Qiming; Chang, Brian; Brulois, Kevin F; Castro, Kamilah; Min, Chan-Ki; Rodgers, Mary A; Shi, Mude; Ge, Jianning; Feng, Pinghui; Oh, Byung-Ha; Jung, Jae U

    2013-11-01

    Autophagy is an important innate safeguard mechanism for protecting an organism against invasion by pathogens. We have previously discovered that Kaposi's sarcoma-associated herpesvirus (KSHV) evades this host defense through tight suppression of autophagy by targeting multiple steps of autophagy signal transduction. Here, we report that KSHV K7 protein interacts with Rubicon autophagy protein and inhibits the autophagosome maturation step by blocking Vps34 enzymatic activity, further highlighting how KSHV deregulates autophagy-mediated host immunity for its life cycle.

  13. Modulation of phenotypic and functional maturation of murine dendritic cells (DCs) by purified Achyranthes bidentata polysaccharide (ABP).

    PubMed

    Zou, Yaxuan; Meng, Jingjuan; Chen, Wenna; Liu, Jingling; Li, Xuan; Li, Weiwei; Lu, Changlong; Shan, Fengping

    2011-08-01

    There are a large number of interactions at molecular and cellular levels between the plant polysaccharides and immune system. Plant polysaccharides present an interesting effects as immunomodulators, particularly in the induction of the cells both in innate and adaptive immune systems. Activation of DCs could improve antitumoral responses usually diminished in cancer patients, and natural adjuvants provide a possibility of inducing this activation. ABP is a purified polysaccharide isolated from Achyranthes bidentata, a traditional Chinese medicine (TCM). The aim of this study is to investigate modulation of phenotypic and functional maturation of murine DCs by ABP. Both phenotypic and functional activities were assessed with use of conventional scanning electronic microscopy (SEM) for the morphology of the DC, transmitted electron microscopy (TEM) for intracellular lysosomes inside the DC, cellular immunohistochemistry for phagocytosis by the DCs, flow cytometry (FCM) for the changes in key surface molecules, bio-assay for the activity of acidic phosphatases (ACP), and ELISA for the production of pro-inflammatory cytokine IL-12. In fact, we found that purified ABP induced phenotypic maturation revealed by increased expression of CD86, CD40, and MHC II. Functional experiments showed the down-regulation of ACP inside DCs (which occurs when phagocytosis of DCs is decreased, and antigen presentation increased with maturation). Finally, ABP increased the production of IL-12. These data reveal that ABP promotes effective activation of murine DCs. This adjuvant-like activity may have therapeutic applications in clinical settings where immune responses need boosting. It is therefore concluded that ABP can exert positive modulation to murine DCs.

  14. Modulation of T-bet and Eomes during Maturation of Peripheral Blood NK Cells Does Not Depend on Licensing/Educating KIR.

    PubMed

    Pradier, Amandine; Simonetta, Federico; Waldvogel, Sophie; Bosshard, Carine; Tiercy, Jean-Marie; Roosnek, Eddy

    2016-01-01

    Peripheral natural killer (NK) cells upregulate T-bet and downregulate Eomes, the key transcription factors regulating NK cell maturation and function during the last maturation steps toward terminally differentiated effector cells. During this process, NK cells acquire killer immunoglobulin-like receptors (KIR) and effector functions, such as cytotoxicity and target cell-induced cytokine production. Inhibitory KIR are pivotal in the control of effector functions, but whether they also modulate T-bet/Eomes expression is unknown. We have measured T-bet/Eomes levels, KIR expression, and effector functions of maturing CD94(neg)CD56(dim)NK cells using CD57 as surface marker for maturation. Our cohort consisted of 23 healthy blood donors (HBD) homozygous for the KIR A haplotype that contains only inhibitory KIR2DL1 (ligand HLA-C2), KIR2DL3 (ligand HLA-C1), and KIR3DL1 (ligand HLA-Bw4). We confirm that during maturation of NK cells, the number of KIR increases, levels of T-bet/Eomes are modulated, and that cells acquire effector functions, such as cytotoxicity (CD107) and target cell-induced cytokine production (TNF-α). Because maturation was associated with the increase of the number of KIR as well as with the modulation of T-bet/Eomes, the number of KIR correlated with the extent of T-bet/Eomes modulation. However, whether the KIR were triggered by their cognate HLA ligands or not had no impact on T-bet and Eomes expression, indicating that modulation of T-box transcription factors during NK cell maturation does not depend on signals conveyed by KIR. We discuss the relevance of this finding in the context of models of NK cell maturation while cautioning that results obtained in a perhaps quite heterogeneous cohort of HBD are not necessarily conclusive.

  15. TwinFocus, a concentrated photovoltaic module based on mature technologies

    NASA Astrophysics Data System (ADS)

    Antonini, Piergiorgio; Centro, Sandro; Golfetto, Stelvio; Saccà, Alessandro

    2014-12-01

    Among solar power generation, concentrated photovoltaics (CPV) based on multijunction (MJ) solar cells, is one of the most promising technology for hot climates. The fact that multijunction solar cells based on direct band gap semiconductors demonstrate lower dependence on temperature than silicon solar cells boosted their use in concentrated photovoltaics modules. Departing from the mainstream design of Fresnel lenses, the CPV module based on TwinFocus design with off-axis quasi parabolic mirrors differentiates itself for its compactness and the possibility of easy integration also in roof-top applications. A detailed description of the module and of the systems will be given together with measured performances, and expectations for the next release.

  16. WASH drives early recycling from macropinosomes and phagosomes to maintain surface phagocytic receptors

    PubMed Central

    Buckley, Catherine M.; Gopaldass, Navin; Bosmani, Cristina; Johnston, Simon A.; Insall, Robert H.

    2016-01-01

    Macropinocytosis is an ancient mechanism that allows cells to harvest nutrients from extracellular media, which also allows immune cells to sample antigens from their surroundings. During macropinosome formation, bulk plasma membrane is internalized with all its integral proteins. It is vital for cells to salvage these proteins before degradation, but the mechanisms for sorting them are not known. Here we describe the evolutionarily conserved recruitment of the WASH (WASP and SCAR homolog) complex to both macropinosomes and phagosomes within a minute of internalization. Using Dictyostelium, we demonstrate that WASH drives protein sorting and recycling from macropinosomes and is thus essential to maintain surface receptor levels and sustain phagocytosis. WASH functionally interacts with the retromer complex at both early and late phases of macropinosome maturation, but mediates recycling via retromer-dependent and -independent pathways. WASH mutants consequently have decreased membrane levels of integrins and other surface proteins. This study reveals an important pathway enabling cells to sustain macropinocytosis without bulk degradation of plasma membrane components. PMID:27647881

  17. Redox-sensitive probes for the measurement of redox chemistries within phagosomes of macrophages and dendritic cells☆

    PubMed Central

    Balce, Dale R.; Yates, Robin M.

    2013-01-01

    There is currently much interest in factors that affect redox chemistries within phagosomes of macrophages and dendritic cells. In addition to the antimicrobial role of reactive oxygen species generation within phagosomes, accumulating evidence suggests that phagosomal redox chemistries influence other phagosomal functions such as macromolecular degradation and antigen processing. Whilst the redox chemistries within many sub-cellular compartments are being heavily scrutinized with the increasing use of fluorescent probe technologies, there is a paucity of tools to assess redox conditions within phagosomes. Hence the systems that control redox homeostasis in these unique environments remain poorly defined. This review highlights current redox-sensitive probes that can measure oxidative or reductive activity in phagosomes and discusses their suitability and limitations of use. Probes that are easily targeted to the phagosome by using established approaches are emphasized. PMID:24191242

  18. Early postnatal GABAA receptor modulation reverses deficits in neuronal maturation in a conditional neurodevelopmental mouse model of DISC1

    PubMed Central

    Saito, Atsushi; Taniguchi, Yu; Rannals, Matthew D.; Merfeld, Emily B.; Ballinger, Michael D.; Koga, Minori; Ohtani, Yoshikazu; Gurley, David A.; Sedlak, Thomas W.; Cross, Alan; Moss, Stephen J.; Brandon, Nicholas J.; Maher, Brady J.; Kamiya, Atsushi

    2015-01-01

    Exploring drug targets based on disease-associated molecular mechanisms during development is crucial for the generation of novel prevention and treatment strategies for neurodevelopmental psychiatric conditions. We report that prefrontal cortex-specific postnatal knockdown of DISC1 via in utero electroporation combined with an inducible knockdown expression system drives deficits in synaptic GABAA function and dendritic development in pyramidal neurons, as well as abnormalities in sensorimotor gating, albeit without profound memory deficits. We show for the first time that DISC1 is specifically involved in regulating cell surface expression of α2 subunit-containing GABAA receptors in immature developing neurons, but not after full maturation. Notably, pharmacological intervention with α2/3 subtype-selective GABAA receptor positive allosteric modulators during the early postnatal period ameliorates dendritic deficits and behavioral abnormalities induced by knockdown of DISC1. These findings highlight a critical role of DISC1-mediated disruption of postnatal GABA signaling in aberrant prefrontal cortex maturation and function. PMID:26728564

  19. Acidification of phagosomes is initiated before lysosomal enzyme activity is detected

    PubMed Central

    1983-01-01

    We have measured changes of pH in a protein's microenvironment consequent on its binding to the cell surface and incorporation into pinosomes. Changes of pH were measured from single, living cells and selected regions of cells by the fluorescence ratio technique using a photon-counting microspectrofluorimeter. The chemotactic agent and pinocytosis inducer, ribonuclease, labeled with fluorescein (FTC- RNase), adsorbed to the surface of Amoeba proteus, and was pinocytosed by cells in culture media at pH 7.0. The FTC-RNase entered an apparently acidic microenvironment, pH approximately 6.1, upon binding to the surface of amoebae. Once enclosed within pinosomes, this protein's microenvironment became steadily more acidic, reaching a minimum of pH approximately 5.6 in less than 10 min. FTC-RNase pinocytosed by the giant amoeba, Chaos carolinensis, entered pinosomes whose pH was correlated with their cytoplasmic location during the initial 30-40 min after pinocytosis. The majority of pinosomes containing FTC-RNase clustered in the tail ectoplasm of C. carolinensis during this interval and had a pH of approximately 6.5; those released into endoplasm and carried into the tip of cells had a pH below 5.0. As pinosomes became distributed at random in C. carolinensis (1-2 h after initial pinocytosis), differences in pH between tip and tail pinosomes vanished. We have also measured the pH within single phagosomes of A. proteus. Phagosomal pH dropped steadily to approximately 5.4 within 5 min after particle ingestion in 70% of the cells measured, and reached this level of acidity within 10 min in 90% of the cells measured. By contrast, stain for the lysosomal enzyme, acid phosphatase, was evident within only 20% of 5-min-old phagosomes visualized by light microscopy, and within only 40% of 10-min-old phagosomes. A microfluorimetric assay was used to simultaneously record changes in pH, and the initial deposition of lysosomal esterases, within phagosomes of single, living Amoeba

  20. Bovine whey protein concentrate supplementation modulates maturation of immune system in suckling rats.

    PubMed

    Pérez-Cano, Francisco J; Marín-Gallén, Silvia; Castell, Margarida; Rodríguez-Palmero, María; Rivero, Montserrat; Franch, Angels; Castellote, Cristina

    2007-10-01

    During neonatal life, challenges from breast milk and microbial flora promote immune system maturation. Immunonutrition in these stages may become an important way to increase natural defence systems. The aim of this study was to determine the effect of a daily bovine milk whey protein concentrate (WPC) supplement on the intestinal and systemic immune systems in suckling rats. The composition of intraepithelial and lamina propria lymphocytes (IEL and LPL) was analysed by flow cytometry. Systemic and intestinal humoral immune responses were determined by sera Ig levels and Ig-secreting cell quantification by ELISA and ELISPOT, respectively. From birth, suckling Wistar rats were supplemented with WPC or standard infant formula (SIF). The WPC group showed the same proportion of most of the main mucosal cell subsets as the reference animals. However, in the first days of life WPC enhanced the innate immunity by increasing the NK cell proportion in both epithelial and lamina propria (LP) compartments. A rise in intestinal CD8alphaalpha+ IEL was also induced by WPC supplementation. A time-course of sera Ig levels and spontaneous IgA, IgM and IgG production by LPL and mononuclear cells from blood and spleen, in the WPC group, exhibited a similar pattern to those pups fed only by dam's milk. In summary, the present results show the effects of WPC on enhancing mucosal innate immunity during early life.

  1. Modulation of paired-pulse responses in the dentate gyrus: effects of normal maturation and vigilance state.

    PubMed

    Blaise, J H; Bronzino, J D

    2000-01-01

    This study examined the effect of normal development and vigilance state on the modulation of dentate granule cell activity in the freely moving rat at 15, 30, and 90 days of age across three vigilance states: quiet waking, slow-wave sleep, and rapid eye movement sleep. Using paired-pulse stimulation, the paired-pulse index (PPI) was obtained for the dentate evoked field potentials elicited by the stimulation of the medial perforant path. Although significant differences in PPI values were observed during development, no significant vigilance state related changes were obtained. Preweaning infant rats, i.e., 15-day old, exhibited significantly less early (interpulse intervals, IPI= 20-50 ms) and late (IPI = 300-1,000 ms) inhibition, and less facilitation (IPI = 50-150 ms) when compared to the 90-day old adult rats during all three vigilance states. PPI values obtained from the 30-day old group fell intermediate between the 15- and 90-day old animals. These changes in PPI values provide a quantitative measure of changes in the modulation of dentate granule cell excitability during normal maturation. They can now can be used to evaluate the impact of various insults, such as prenatal protein malnutrition or neonatal stress, on hippocampal development.

  2. Cognitive flexibility modulates maturation and music-training-related changes in neural sound discrimination.

    PubMed

    Saarikivi, Katri; Putkinen, Vesa; Tervaniemi, Mari; Huotilainen, Minna

    2016-07-01

    Previous research has demonstrated that musicians show superior neural sound discrimination when compared to non-musicians, and that these changes emerge with accumulation of training. Our aim was to investigate whether individual differences in executive functions predict training-related changes in neural sound discrimination. We measured event-related potentials induced by sound changes coupled with tests for executive functions in musically trained and non-trained children aged 9-11 years and 13-15 years. High performance in a set-shifting task, indexing cognitive flexibility, was linked to enhanced maturation of neural sound discrimination in both musically trained and non-trained children. Specifically, well-performing musically trained children already showed large mismatch negativity (MMN) responses at a young age as well as at an older age, indicating accurate sound discrimination. In contrast, the musically trained low-performing children still showed an increase in MMN amplitude with age, suggesting that they were behind their high-performing peers in the development of sound discrimination. In the non-trained group, in turn, only the high-performing children showed evidence of an age-related increase in MMN amplitude, and the low-performing children showed a small MMN with no age-related change. These latter results suggest an advantage in MMN development also for high-performing non-trained individuals. For the P3a amplitude, there was an age-related increase only in the children who performed well in the set-shifting task, irrespective of music training, indicating enhanced attention-related processes in these children. Thus, the current study provides the first evidence that, in children, cognitive flexibility may influence age-related and training-related plasticity of neural sound discrimination.

  3. The Cell Wall Lipid PDIM Contributes to Phagosomal Escape and Host Cell Exit of Mycobacterium tuberculosis

    PubMed Central

    Quigley, Jeff; Hughitt, V. Keith; Velikovsky, Carlos A.; Mariuzza, Roy A.

    2017-01-01

    ABSTRACT The cell wall of Mycobacterium tuberculosis is composed of unique lipids that are important for pathogenesis. Indeed, the first-ever genetic screen in M. tuberculosis identified genes involved in the biosynthesis and transport of the cell wall lipid PDIM (phthiocerol dimycocerosates) as crucial for the survival of M. tuberculosis in mice. Here we show evidence for a novel molecular mechanism of the PDIM-mediated virulence in M. tuberculosis. We characterized the DNA interaction and the regulon of Rv3167c, a transcriptional repressor that is involved in virulence regulation of M. tuberculosis, and discovered that it controls the PDIM operon. A loss-of-function genetic approach showed that PDIM levels directly correlate with the capacity of M. tuberculosis to escape the phagosome and induce host cell necrosis and macroautophagy. In conclusion, our study attributes a novel role of the cell wall lipid PDIM in intracellular host cell modulation, which is important for host cell exit and dissemination of M. tuberculosis. PMID:28270579

  4. Hormonal Modulation of Dendritic Cells Differentiation, Maturation and Function: Implications for the Initiation and Progress of Systemic Autoimmunity.

    PubMed

    Mackern-Oberti, Juan Pablo; Jara, Evelyn L; Riedel, Claudia A; Kalergis, Alexis M

    2017-04-01

    Hormonal homeostasis is crucial for keeping a competent and healthy immune function. Several hormones can modulate the function of various immune cells such as dendritic cells (DCs) by influencing the initiation of the immune response and the maintenance of peripheral tolerance to self-antigens. Hormones, such as estrogens, prolactin, progesterone and glucocorticoids may profoundly affect DCs differentiation, maturation and function leading to either a pro-inflammatory or an anti-inflammatory (or tolerogenic) phenotype. If not properly regulated, these processes can contribute to the pathogenesis of autoimmune disease. An unbalanced hormonal status may affect the production of pro-inflammatory cytokines, the expression of activating/inhibitory receptors and co-stimulatory molecules on conventional and plasmacytoid DCs (pDCs), conferring susceptibility to develop autoimmunity. Estrogen receptor (ER)-α signaling in conventional DCs can promote IFN-α and IL-6 production and induce the expression of CD40, CD86 and MHCII molecules. Furthermore, estrogen modulates the pDCs response to Toll-like receptor ligands enhancing T cell priming. During lupus pathogenesis, ER-α deficiency decreased the expression of MHC II on pDCs from the spleen. In contrast, estradiol administration to lupus-prone female mice increased the expression of co-stimulatory molecules, enhanced the immunogenicity and produced large amounts of IL-6, IL-12 and TNF-α by bone marrow-derived DCs. These data suggest that estradiol/ER signaling may play an active role during lupus pathology. Similarly, understanding hormonal modulation of DCs may favor the design of new therapeutic strategies based on autologous tolerogenic DCs transfer, especially in sex-biased systemic autoimmune diseases. In this review, we discuss recent data relative to the role of different hormones (estrogen, prolactin, progesterone and glucocorticoids) in DC function during systemic autoimmune pathogenesis.

  5. Anaplasma marginale Actively Modulates Vacuolar Maturation during Intracellular Infection of Its Tick Vector, Dermacentor andersoni

    PubMed Central

    Thompson, Chelsea Wright; Schneider, David A.; Noh, Susan M.

    2016-01-01

    ABSTRACT Tick-borne transmission of bacterial pathogens in the order Rickettsiales is responsible for diverse infectious diseases, many of them severe, in humans and animals. Transmission dynamics differ among these pathogens and are reflected in the pathogen-vector interaction. Anaplasma marginale has been shown to establish and maintain infectivity within Dermacentor spp. for weeks to months while escaping the complex network of vacuolar peptidases that are responsible for digestion of the tick blood meal. How this prolonged maintenance of infectivity in a potentially hostile environment is achieved has been unknown. Using the natural vector Dermacentor andersoni, we demonstrated that A. marginale-infected tick vacuoles (AmVs) concurrently recruit markers of the early endosome (Rab5), recycling endosome (Rab4 and Rab11), and late endosome (Rab7), are maintained near neutral pH, do not fuse with lysosomes, exclude the protease cathepsin L, and engage the endoplasmic reticulum and Golgi apparatus for up to 21 days postinfection. Maintenance of this safe vacuolar niche requires active A. marginale protein synthesis; in its absence, the AmVs mature into acidic, protease-active phagolysosomes. Identification of this bacterially directed modeling of the tick midgut endosome provides a mechanistic basis for examination of the differences in transmission efficiency observed among A. marginale strains and among vector populations. IMPORTANCE Ticks transmit a variety of intracellular bacterial pathogens that cause significant diseases in humans and animals. For successful transmission, these bacterial pathogens must first gain entry into the tick midgut digestive cells, avoid digestion, and establish a replicative niche without harming the tick vector. Little is known about how this replicative niche is established and maintained. Using the ruminant pathogen A. marginale and its natural tick vector, D. andersoni, this study characterized the features of the A. marginale

  6. Developmental competence of mature yak vitrified-warmed oocytes is enhanced by IGF-I via modulation of CIRP during in vitro maturation.

    PubMed

    Pan, Yangyang; Cui, Yan; He, Honghong; Baloch, Abdul Rasheed; Fan, Jiangfeng; Xu, Gengquan; He, Junfeng; Yang, Kun; Li, Guyue; Yu, Sijiu

    2015-12-01

    The objective of this study was to investigate whether developmental competence of mature vitrified-warmed yak (Bos grunniens) oocytes can be enhanced by supplemented insulin-like growth factor I (IGF-1) during in vitro maturation (IVM), and its relationship with the expression of cold-inducible RNA-binding protein (CIRP). In experiment 1, immature yak oocytes were divided into four groups, and IVM supplemented with 0, 50, 100 and 200 ng/mL IGF-1 was evaluated; the mRNA and protein expression levels of CIRP in mature oocytes in the four groups were evaluated using quantitative real-time PCR and western blotting analyses. In experiment 2, the mature yak oocytes in the four groups were cryopreserved using the Cryotop (CT) method, followed by chemical activation and in vitro culture for two days and eight days to determine cleavage, blastocyst rates, and total cell number in the blastocysts. Mature yak oocytes without vitrification served as a control group. The outcomes were as following: (1) the expression of CIRP in the matured oocytes was up-regulated in the IGF-1 groups and was highest expression was observed in the 100 ng/mL IGF-1 treatment group. (2) In the vitrified-warmed groups, the rates of cleavage and blastocyst were also highest in the 100 ng/mL IGF-1 treatment group (81.04 ± 1.06%% and 32.16 ± 1.01%), which were close to the rates observed in groups without vitrification (83.25 ± 0.85% and 32.54 ± 0.34%). The rates of cleavage and blastocyst in the other vitrified-warmed groups were 70.92 ± 1.32% and 27.33 ± 1.31% (0 ng/mL); 72.73 ± 0.74% and 29.41 ± 0.84% (50 ng/mL); 72.43 ± 0.61% and 27.61 ± 0.59% (200 ng/mL), respectively. There was no significant difference in the total cell number per blastocysts between the vitrified-warmed groups and group without vitrification. Thus, we conclude that the enhancement in developmental competence of mature yak vitrified-warmed oocytes after the addition of IGF-1 during IVM might result from the regulation

  7. Morphine Modulates Adult Neurogenesis and Contextual Memory by Impeding the Maturation of Neural Progenitors.

    PubMed

    Zhang, Yue; Xu, Chi; Zheng, Hui; Loh, Horace H; Law, Ping-Yee

    2016-01-01

    The regulation of adult neurogenesis by opiates has been implicated in modulating different addiction cycles. At which neurogenesis stage opiates exert their action remains unresolved. We attempt to define the temporal window of morphine's inhibition effect on adult neurogenesis by using the POMC-EGFP mouse model, in which newborn granular cells (GCs) can be visualized between days 3-28 post-mitotic. The POMC-EGFP mice were trained under the 3-chambers conditioned place preference (CPP) paradigm with either saline or morphine. We observed after 4 days of CPP training with saline, the number of EGFP-labeled newborn GCs in sub-granular zone (SGZ) hippocampus significantly increased compared to mice injected with saline in their homecage. CPP training with morphine significantly decreased the number of EGFP-labeled GCs, whereas no significant difference in the number of EGFP-labeled GCs was observed with the homecage mice injected with the same dose of morphine. Using cell-type selective markers, we observed that morphine reduced the number of late stage progenitors and immature neurons such as Doublecortin (DCX) and βIII Tubulin (TuJ1) positive cells in the SGZ but did not reduce the number of early progenitors such as Nestin, SOX2, or neurogenic differentiation-1 (NeuroD1) positive cells. Analysis of co-localization between different cell markers shows that morphine reduced the number of adult-born GCs by interfering with differentiation of early progenitors, but not by inducing apoptosis. In addition, when NeuroD1 was over-expressed in DG by stereotaxic injection of lentivirus, it rescued the loss of immature neurons and prolonged the extinction of morphine-trained CPP. These results suggest that under the condition of CPP training paradigm, morphine affects the transition of neural progenitor/stem cells to immature neurons via a mechanism involving NeuroD1.

  8. Morphine Modulates Adult Neurogenesis and Contextual Memory by Impeding the Maturation of Neural Progenitors

    PubMed Central

    Zhang, Yue; Xu, Chi; Zheng, Hui; Loh, Horace H.; Law, Ping-Yee

    2016-01-01

    The regulation of adult neurogenesis by opiates has been implicated in modulating different addiction cycles. At which neurogenesis stage opiates exert their action remains unresolved. We attempt to define the temporal window of morphine’s inhibition effect on adult neurogenesis by using the POMC-EGFP mouse model, in which newborn granular cells (GCs) can be visualized between days 3–28 post-mitotic. The POMC-EGFP mice were trained under the 3-chambers conditioned place preference (CPP) paradigm with either saline or morphine. We observed after 4 days of CPP training with saline, the number of EGFP-labeled newborn GCs in sub-granular zone (SGZ) hippocampus significantly increased compared to mice injected with saline in their homecage. CPP training with morphine significantly decreased the number of EGFP-labeled GCs, whereas no significant difference in the number of EGFP-labeled GCs was observed with the homecage mice injected with the same dose of morphine. Using cell-type selective markers, we observed that morphine reduced the number of late stage progenitors and immature neurons such as Doublecortin (DCX) and βIII Tubulin (TuJ1) positive cells in the SGZ but did not reduce the number of early progenitors such as Nestin, SOX2, or neurogenic differentiation-1 (NeuroD1) positive cells. Analysis of co-localization between different cell markers shows that morphine reduced the number of adult-born GCs by interfering with differentiation of early progenitors, but not by inducing apoptosis. In addition, when NeuroD1 was over-expressed in DG by stereotaxic injection of lentivirus, it rescued the loss of immature neurons and prolonged the extinction of morphine-trained CPP. These results suggest that under the condition of CPP training paradigm, morphine affects the transition of neural progenitor/stem cells to immature neurons via a mechanism involving NeuroD1. PMID:27078155

  9. Differential modulation of resistance biomarkers in skin of juvenile and mature pink salmon, Oncorhynchus gorbuscha by the salmon louse, Lepeophtheirus salmonis.

    PubMed

    Braden, Laura M; Barker, Duane E; Koop, Ben F; Jones, Simon R M

    2015-11-01

    Juvenile pink salmon larger than 0.7 g reject the sea louse, Lepeophtheirus salmonis, and are considered resistant to the infection. Robust innate defense responses in the skin contribute to the observed resistance. In contrast adult pink salmon captured at sea or shortly before spawning carry large numbers of the parasite, suggesting inability to control the infection. The purpose of this research is to better understand these apparently contradictory conclusions by comparing a suite of genetic and cellular markers of resistance to L. salmonis in the skin of juvenile and mature pink salmon. The expression of major histocompatibility factor II, C-reactive protein, interleukin-1β, interleukin-8 and cyclooxygenase-2 was down-regulated in mature but not juvenile pink salmon. Similarly, skin at the site of parasite attachment in juvenile salmon was highly populated with MHIIβ(+) and IL-1β(+) cells that were either absent, or at reduced levels at similar sites in mature salmon. In addition, mucocyte density was relatively low in the skin of mature salmon, irrespective of louse infection. In juveniles, the higher mucocyte density decreased following louse attachment. We show that in mature pink salmon, genetic and histological responses in skin are depressed and speculate that salmonid defense against L. salmonis is modulated by maturation.

  10. Photoreceptor phagosome processing defects and disturbed autophagy in retinal pigment epithelium of Cln3Δex1-6 mice modelling juvenile neuronal ceroid lipofuscinosis (Batten disease)

    PubMed Central

    Wavre-Shapton, Silène T.; Calvi, Alessandra A.; Turmaine, Mark; Seabra, Miguel C.; Cutler, Daniel F.; Futter, Clare E.; Mitchison, Hannah M.

    2015-01-01

    Retinal degeneration and visual impairment are the first signs of juvenile neuronal ceroid lipofuscinosis caused by CLN3 mutations, followed by inevitable progression to blindness. We investigated retinal degeneration in Cln3Δex1-6 null mice, revealing classic ‘fingerprint’ lysosomal storage in the retinal pigment epithelium (RPE), replicating the human disease. The lysosomes contain mitochondrial F0-ATP synthase subunit c along with undigested membranes, indicating a reduced degradative capacity. Mature autophagosomes and basal phagolysosomes, the terminal degradative compartments of autophagy and phagocytosis, are also increased in Cln3Δex1-6 RPE, reflecting disruption to these key pathways that underpin the daily phagocytic turnover of photoreceptor outer segments (POS) required for maintenance of vision. The accumulated autophagosomes have post-lysosome fusion morphology, with undigested internal contents visible, while accumulated phagosomes are frequently docked to cathepsin D-positive lysosomes, without mixing of phagosomal and lysosomal contents. This suggests lysosome-processing defects affect both autophagy and phagocytosis, supported by evidence that phagosomes induced in Cln3Δex1-6-derived mouse embryonic fibroblasts have visibly disorganized membranes, unprocessed internal vesicles and membrane contents, in addition to reduced LAMP1 membrane recruitment. We propose that defective lysosomes in Cln3Δex1-6 RPE have a reduced degradative capacity that impairs the final steps of the intimately connected autophagic and phagocytic pathways that are responsible for degradation of POS. A build-up of degradative organellar by-products and decreased recycling of cellular materials is likely to disrupt processes vital to maintenance of vision by the RPE. PMID:26450516

  11. Mycobacterial escape from macrophage phagosomes to the cytoplasm represents an alternate adaptation mechanism

    PubMed Central

    Jamwal, Shilpa V.; Mehrotra, Parul; Singh, Archana; Siddiqui, Zaved; Basu, Atanu; Rao, Kanury V.S.

    2016-01-01

    Survival of Mycobacterium tuberculosis (Mtb) within the host macrophage is mediated through pathogen-dependent inhibition of phagosome-lysosome fusion, which enables bacteria to persist within the immature phagosomal compartment. By employing ultrastructural examination of different field isolates supported by biochemical analysis, we found that some of the Mtb strains were in fact poorly adapted for subsistence within endocytic vesicles of infected macrophages. Instead, through a mechanism involving activation of host cytosolic phospholipase A2, these bacteria rapidly escaped from phagosomes, and established residence in the cytoplasm of the host cell. Interestingly, by facilitating an enhanced suppression of host cellular autophagy, this translocation served as an alternate virulence acquisition mechanism. Thus, our studies reveal plasticity in the adaptation strategies employed by Mtb, for survival in the host macrophage. PMID:26980157

  12. Initial cytoplasmic and phagosomal consequences of human neutrophil exposure to Staphylococcus epidermidis.

    PubMed

    Bernardo, John; Long, Heidi J; Simons, Elizabeth R

    2010-03-01

    Microorganisms are recognized by specific phagocyte surface receptors. Liganded receptors then signal a series of events leading to phagocytosis and destruction of the organism by oxidative, lytic, and associated processes. Some organisms, such as Mycobacterium tuberculosis (Mtb), Cryptococcus neoformans (Cf), and others, evade such destruction, surviving and sometimes multiplying within the phagosome to later cause disease. To study such evasion, we developed protocols which permit simultaneous kinetic measurement of early cytoplasmic signaling and of phagosomal pH (pH(p)) and oxidative burst, on a cell-by-cell basis, of polymorphonuclear (PMN) leukocytes exposed to fluorescently labeled, nonpathogenic Staphylococcus epidermidis (Se). The availability of a new, highly sensitive pH probe, pHrodo, permits observation of increasing pH(p). Simultaneous labeling of the organism, applicable to any phagocyte target, with a probe insensitive to pH and oxidative species, such as AlexaFluor350, permits distinction between binding and functional responses to it by ratioing fluorescences. Addition of an extracellular-specific quencher (Trypan blue) permits distinction between bound and phagosome-enclosed targets, so that conditions within the closed phagosome can be studied. We found that opsonization is required for functional activation of PMN by Se, that the organism causes early alkalinization of the phagosome (in contrast to Cf which hyperacidifies it), and that extracellular Ca(2+) is not required for cytoplasmic Ca(2+) signaling but contributes markedly to binding of Se to PMN and to ensuant bactericidal functions. These findings lead to a new approach to the study of select organisms, like Cf and Mtb, which evade killing by manipulating the phagosomal environment.

  13. CCL-34, a synthetic toll-like receptor 4 activator, modulates differentiation and maturation of myeloid dendritic cells.

    PubMed

    Fu, Shu-Ling; Lin, Chun-Cheng; Hsu, Ming-Ling; Liu, Sheng-Hung; Huang, Yu-Chuen; Chen, Yu-Jen

    2016-03-08

    CCL-34, a synthetic α-galactosylceramide analog, has been reported as an activator of toll-like receptor 4 (TLR4) in macrophages. TLR4 is highly expressed in dendritic cell (DC) and several TLR4 agonists are known to trigger DC maturation. We herein evaluated the effect of CCL-34 on DC maturation. Human CD14+ monocyte-derived immature DC were treated with CCL-34, its inactive structural analog CCL-44, or LPS to assess the DC maturation. CCL-34 induced DC maturation according to their characteristically dendrite-forming morphology, CD83 expression and IL-12p70 production. The allostimulatory activity of DC on proliferation of naive CD4+CD45+RA+ T cells and their secretion of interferon-γ was increased by CCL-34. Phagocytosis, an important function of immature DC, was reduced after CCL-34 treatment. All these effects related to DC maturation were evidently induced by positive control LPS but not by CCL-44 treatment. TLR4 neutralization impaired human DC maturation triggered by CCL-34. The induction of IL-12, a hallmark of DC maturation, by CCL-34 and LPS was only evident in TLR4-competent C3H/HeN, but not in TLR4-defective C3H/HeJ mice. CCL-34 could further elicit the antigen presentation capability in mice inoculated with doxorubicin-treated colorectal cancer cells. In summary, CCL-34 triggers DC maturation via a TLR4-dependent manner, which supports its potential application as an immunostimulator.

  14. Polyamine-induced modulation of genes involved in ethylene biosynthesis and signalling pathways and nitric oxide production during olive mature fruit abscission

    PubMed Central

    Parra-Lobato, Maria C.; Gomez-Jimenez, Maria C.

    2011-01-01

    After fruit ripening, many fruit-tree species undergo massive natural fruit abscission. Olive (Olea europaea L.) is a stone-fruit with cultivars such as Picual (PIC) and Arbequina (ARB) which differ in mature fruit abscission potential. Ethylene (ET) is associated with abscission, but its role during mature fruit abscission remains largely uncharacterized. The present study investigates the possible roles of ET and polyamine (PA) during mature fruit abscission by modulating genes involved in the ET signalling and biosynthesis pathways in the abscission zone (AZ) of both cultivars. Five ET-related genes (OeACS2, OeACO2, OeCTR1, OeERS1, and OeEIL2) were isolated in the AZ and adjacent cells (AZ–AC), and their expression in various olive organs and during mature fruit abscission, in relation to interactions between ET and PA and the expression induction of these genes, was determined. OeACS2, OeACO2, and OeEIL2 were found to be the only genes that were up-regulated in association with mature fruit abscission. Using the inhibition of ET and PA biosynthesis, it is demonstrated that OeACS2 and OeEIL2 expression are under the negative control of PA while ET induces their expression in AZ–AC. Furthermore, mature fruit abscission depressed nitric oxide (NO) production present mainly in the epidermal cells and xylem of the AZ. Also, NO production was differentially responsive to ET, PA, and different inhibitors. Taken together, the results indicate that PA-dependent ET signalling and biosynthesis pathways participate, at least partially, during mature fruit abscission, and that endogenous NO and 1-aminocyclopropane-1-carboxylic acid maintain an inverse correlation, suggesting an antagonistic action of NO and ET in abscission signalling. PMID:21633085

  15. Role of the Brucella suis Lipopolysaccharide O Antigen in Phagosomal Genesis and in Inhibition of Phagosome-Lysosome Fusion in Murine Macrophages

    PubMed Central

    Porte, Françoise; Naroeni, Aroem; Ouahrani-Bettache, Safia; Liautard, Jean-Pierre

    2003-01-01

    Brucella species are gram-negative, facultative intracellular bacteria that infect humans and animals. These organisms can survive and replicate within a membrane-bound compartment inside professional and nonprofessional phagocytic cells. Inhibition of phagosome-lysosome fusion has been proposed as a mechanism for intracellular survival in both cell types. However, the molecular mechanisms and the microbial factors involved are poorly understood. Smooth lipopolysaccharide (LPS) of Brucella has been reported to be an important virulence factor, although its precise role in pathogenesis is not yet clear. In this study, we show that the LPS O side chain is involved in inhibition of the early fusion between Brucella suis-containing phagosomes and lysosomes in murine macrophages. In contrast, the phagosomes containing rough mutants, which fail to express the O antigen, rapidly fuse with lysosomes. In addition, we show that rough mutants do not enter host cells by using lipid rafts, contrary to smooth strains. Thus, we propose that the LPS O chain might be a major factor that governs the early behavior of bacteria inside macrophages. PMID:12595466

  16. CCL-34, a synthetic toll-like receptor 4 activator, modulates differentiation and maturation of myeloid dendritic cells

    PubMed Central

    Fu, Shu-Ling; Lin, Chun-Cheng; Hsu, Ming-Ling; Liu, Sheng-Hung; Huang, Yu-Chuen; Chen, Yu-Jen

    2016-01-01

    CCL-34, a synthetic α-galactosylceramide analog, has been reported as an activator of toll-like receptor 4 (TLR4) in macrophages. TLR4 is highly expressed in dendritic cell (DC) and several TLR4 agonists are known to trigger DC maturation. We herein evaluated the effect of CCL-34 on DC maturation. Human CD14+ monocyte-derived immature DC were treated with CCL-34, its inactive structural analog CCL-44, or LPS to assess the DC maturation. CCL-34 induced DC maturation according to their characteristically dendrite-forming morphology, CD83 expression and IL-12p70 production. The allostimulatory activity of DC on proliferation of naive CD4+CD45+RA+ T cells and their secretion of interferon-γ was increased by CCL-34. Phagocytosis, an important function of immature DC, was reduced after CCL-34 treatment. All these effects related to DC maturation were evidently induced by positive control LPS but not by CCL-44 treatment. TLR4 neutralization impaired human DC maturation triggered by CCL-34. The induction of IL-12, a hallmark of DC maturation, by CCL-34 and LPS was only evident in TLR4-competent C3H/HeN, but not in TLR4-defective C3H/HeJ mice. CCL-34 could further elicit the antigen presentation capability in mice inoculated with doxorubicin-treated colorectal cancer cells. In summary, CCL-34 triggers DC maturation via a TLR4-dependent manner, which supports its potential application as an immunostimulator. PMID:26883191

  17. Statins reduce amyloid β-peptide production by modulating amyloid precursor protein maturation and phosphorylation through a cholesterol-independent mechanism in cultured neurons.

    PubMed

    Hosaka, Ai; Araki, Wataru; Oda, Akiko; Tomidokoro, Yasushi; Tamaoka, Akira

    2013-03-01

    Statins, 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors, have been reported to attenuate amyloid-β peptide (Aβ) production in various cellular models. However, the mechanisms by which statins affect neuronal Aβ production have not yet been clarified. Here, we investigated this issue in rat primary cortical neurons using two statins, pitavastatin (PV) and atorvastatin (AV). Treatment of neurons with 0.2-2.5 μM PV or AV for 4 days induced a concentration- and time-dependent reduction in the secretion of both Aβ40 and Aβ42. Moreover, Western blot analyses of cell lysates showed that treatment with PV or AV significantly reduced expression levels of the mature form of amyloid precursor protein (APP) and Thr668-phosphorylated APP (P-APP), but not immature form of APP; the decreases in P-APP levels were more notable than those of mature APP levels. The statin treatment did not alter expression of BACE1 (β-site APP-cleaving enzyme 1) or γ-secretase complex proteins (presenilin 1, nicastrin, APH-1, and PEN-2). In neurons overexpressing APP via recombinant adenoviruses, PV or AV similarly reduced Aβ secretion and the levels of mature APP and P-APP. Statins also markedly reduced cellular cholesterol content in neurons in a concentration-dependent manner. Co-treatment with mevalonate reversed the statin-induced decreases in Aβ secretion and mature APP and P-APP levels, whereas co-treatment with cholesterol did not, despite recovery of cellular cholesterol levels. Finally, cell-surface biotinylation experiments revealed that both statins significantly reduced the levels of cell-surface P-APP without changing those of cell surface mature APP. These results suggest that statins reduce Aβ production by selectively modulating APP maturation and phosphorylation through a mechanism independent of cholesterol reduction in cultured neurons.

  18. Retrieval of the Vacuolar H+-ATPase from Phagosomes Revealed by Live Cell Imaging

    PubMed Central

    Clarke, Margaret; Maddera, Lucinda; Engel, Ulrike; Gerisch, Günther

    2010-01-01

    Background The vacuolar H+-ATPase, or V-ATPase, is a highly-conserved multi-subunit enzyme that transports protons across membranes at the expense of ATP. The resulting proton gradient serves many essential functions, among them energizing transport of small molecules such as neurotransmitters, and acidifying organelles such as endosomes. The enzyme is not present in the plasma membrane from which a phagosome is formed, but is rapidly delivered by fusion with endosomes that already bear the V-ATPase in their membranes. Similarly, the enzyme is thought to be retrieved from phagosome membranes prior to exocytosis of indigestible material, although that process has not been directly visualized. Methodology To monitor trafficking of the V-ATPase in the phagocytic pathway of Dictyostelium discoideum, we fed the cells yeast, large particles that maintain their shape during trafficking. To track pH changes, we conjugated the yeast with fluorescein isothiocyanate. Cells were labeled with VatM-GFP, a fluorescently-tagged transmembrane subunit of the V-ATPase, in parallel with stage-specific endosomal markers or in combination with mRFP-tagged cytoskeletal proteins. Principal Findings We find that the V-ATPase is commonly retrieved from the phagosome membrane by vesiculation shortly before exocytosis. However, if the cells are kept in confined spaces, a bulky phagosome may be exocytosed prematurely. In this event, a large V-ATPase-rich vacuole coated with actin typically separates from the acidic phagosome shortly before exocytosis. This vacuole is propelled by an actin tail and soon acquires the properties of an early endosome, revealing an unexpected mechanism for rapid recycling of the V-ATPase. Any V-ATPase that reaches the plasma membrane is also promptly retrieved. Conclusions/Signficance Thus, live cell microscopy has revealed both a usual route and alternative means of recycling the V-ATPase in the endocytic pathway. PMID:20052281

  19. The phagosome containing Legionella pneumophila within the protozoan Hartmannella vermiformis is surrounded by the rough endoplasmic reticulum.

    PubMed Central

    Abu Kwaik, Y

    1996-01-01

    Legionella pneumophila is an intracellular parasite of protozoa and human phagocytes. To examine adaptation of this bacterium to parasitize protozoa, the sequence of events of the intracellular infection of the amoeba Hartmannella vermiformis was examined. The previously described uptake phenomenon of coiling phagocytosis by human monocytes was not detected. A 1 h postinfection with wild-type strain AA100, mitochondria were observed within the vicinity of the phagosome. At 2.5 h postinfection, numerous vesicles surrounded the phagosomes and mitochondria were in close proximity to the phagosome. At 5 h postinfection, the bacterium was surrounded by a ribosome-studded multilayer membrane. Bacterial multiplication was evident by 8 h postinfection, and the phagosome was surrounded by a ribosome-studded multilayer membrane until 15 h postinfection. The recruitment of organelles and formation of the ribosome-studded phagosome was defective in an isogenic attenuated mutant of L. pneumophila (strain AA101A) that failed to replicate within amoebae. At 20 h postinfection with wild-type strain AA100, numerous bacteria were present in the phagosome and ribosome were not detected around the phagosome. These data showed that, at the ultrastructural level, the intracellular infection of protozoa by L. pneumophila is highly similar to that of infection of macrophages. Immunocytochemical studies provided evidence that at 5 h postinfection the phagosome containing L. pneumophila acquired an abundant amount of the endoplasmic reticulum-specific protein (BiP). Similar to phagosomes containing heat-killed wild-type L. pneumophila, the BiP protein was not detectable in phagosomes containing the mutant strain AA101A. In addition to the absence of ribosomes and mitochondria, the BiP protein was not detected in the phagosomes at 20 h postinfection with wild-type L. pneumophila. The data indicated that the ability of L. pneumophila to establish the intracellular infection of amoebae is

  20. A novel role for nuclear factor-erythroid 2 in erythroid maturation by modulation of mitochondrial autophagy

    PubMed Central

    Gothwal, Monika; Wehrle, Julius; Aumann, Konrad; Zimmermann, Vanessa; Gründer, Albert; Pahl, Heike L.

    2016-01-01

    We have recently demonstrated that the transcription factor nuclear factor-erythroid 2, which is critical for erythroid maturation and globin gene expression, plays an important role in the pathophysiology of myeloproliferative neoplasms. Myeloproliferative neoplasm patients display elevated levels of nuclear factor-erythroid 2 and transgenic mice overexpressing the transcription factor develop myeloproliferative neoplasm, albeit, surprisingly without erythrocytosis. Nuclear factor-erythroid 2 transgenic mice show both a reticulocytosis and a concomitant increase in iron deposits in the spleen, suggesting both enhanced erythrocyte production and increased red blood cell destruction. We therefore hypothesized that elevated nuclear factor-erythroid 2 levels may lead to increased erythrocyte destruction by interfering with organelle clearance during erythroid maturation. We have previously shown that nuclear factor-erythroid 2 overexpression delays erythroid maturation of human hematopoietic stem cells. Here we report that increased nuclear factor-erythroid 2 levels also impede murine maturation by retarding mitochondrial depolarization and delaying mitochondrial elimination. In addition, ribosome autophagy is delayed in transgenics. We demonstrate that the autophagy genes NIX and ULK1 are direct novel nuclear factor-erythroid 2 target genes, as these loci are bound by nuclear factor-erythroid 2 in chromatin immunoprecipitation assays. Moreover, Nix and Ulk1 expression is increased in transgenic mice and in granulocytes from polycythemia vera patients. This is the first report implying a role for nuclear factor-erythroid 2 in erythroid maturation by affecting autophagy. PMID:27479815

  1. Tfap2a promotes specification and maturation of neurons in the inner ear through modulation of Bmp, Fgf and notch signaling.

    PubMed

    Kantarci, Husniye; Edlund, Renee K; Groves, Andrew K; Riley, Bruce B

    2015-03-01

    Neurons of the statoacoustic ganglion (SAG) transmit auditory and vestibular information from the inner ear to the hindbrain. SAG neuroblasts originate in the floor of the otic vesicle. New neuroblasts soon delaminate and migrate towards the hindbrain while continuing to proliferate, a phase known as transit amplification. SAG cells eventually come to rest between the ear and hindbrain before terminally differentiating. Regulation of these events is only partially understood. Fgf initiates neuroblast specification within the ear. Subsequently, Fgf secreted by mature SAG neurons exceeds a maximum threshold, serving to terminate specification and delay maturation of transit-amplifying cells. Notch signaling also limits SAG development, but how it is coordinated with Fgf is unknown. Here we show that transcription factor Tfap2a coordinates multiple signaling pathways to promote neurogenesis in the zebrafish inner ear. In both zebrafish and chick, Tfap2a is expressed in a ventrolateral domain of the otic vesicle that includes neurogenic precursors. Functional studies were conducted in zebrafish. Loss of Tfap2a elevated Fgf and Notch signaling, thereby inhibiting SAG specification and slowing maturation of transit-amplifying cells. Conversely, overexpression of Tfap2a inhibited Fgf and Notch signaling, leading to excess and accelerated SAG production. However, most SAG neurons produced by Tfap2a overexpression died soon after maturation. Directly blocking either Fgf or Notch caused less dramatic acceleration of SAG development without neuronal death, whereas blocking both pathways mimicked all observed effects of Tfap2a overexpression, including apoptosis of mature neurons. Analysis of genetic mosaics showed that Tfap2a acts non-autonomously to inhibit Fgf. This led to the discovery that Tfap2a activates expression of Bmp7a, which in turn inhibits both Fgf and Notch signaling. Blocking Bmp signaling reversed the effects of overexpressing Tfap2a. Together, these data

  2. [Modulating the survival and maturation system of B lymphocytes: Current and future new therapeutic strategies in systemic lupus erythematosus].

    PubMed

    Valor, Lara; López-Longo, Francisco Javier

    2015-09-07

    Systemic lupus erythematosus is an autoimmune disease associated with an aberrant production of autoantibodies by self-reactive B lymphocytes. The study of the phenotypic characteristics of B lymphocytes and the identification of their surface receptors such as BAFF-R, TACI and BCMA, which are responsible of their survival and maturation, have contributed to the development of new therapeutic strategies in recent years.

  3. Fetal lipopolysaccharide exposure modulates diet-dependent gut maturation and sensitivity to necrotising enterocolitis in pre-term pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Uterine infections during pregnancy predispose to pre-term birth and postnatal morbidity, but it is unknown how prenatal bacterial exposure affects maturation of the immature gut. We hypothesised that a prenatal exposure to gram-negative lipopolysaccharide (LPS) has immunomodulatory effects that imp...

  4. Novel transmembrane receptor involved in phagosome transport of lysozymes and β-hexosaminidase in the enteric protozoan Entamoeba histolytica.

    PubMed

    Furukawa, Atsushi; Nakada-Tsukui, Kumiko; Nozaki, Tomoyoshi

    2012-02-01

    Lysozymes and hexosaminidases are ubiquitous hydrolases in bacteria and eukaryotes. In phagocytic lower eukaryotes and professional phagocytes from higher eukaryotes, they are involved in the degradation of ingested bacteria in phagosomes. In Entamoeba histolytica, which is the intestinal protozoan parasite that causes amoebiasis, phagocytosis plays a pivotal role in the nutrient acquisition and the evasion from the host defense systems. While the content of phagosomes and biochemical and physiological roles of the major phagosomal proteins have been established in E. histolytica, the mechanisms of trafficking of these phagosomal proteins, in general, remain largely unknown. In this study, we identified and characterized for the first time the putative receptor/carrier involved in the transport of the above-mentioned hydrolases to phagosomes. We have shown that the receptor, designated as cysteine protease binding protein family 8 (CPBF8), is localized in lysosomes and mediates transport of lysozymes and β-hexosaminidase α-subunit to phagosomes when the amoeba ingests mammalian cells or Gram-positive bacillus Clostridium perfringens. We have also shown that the binding of CPBF8 to the cargos is mediated by the serine-rich domain, more specifically three serine residues of the domain, which likely contains trifluoroacetic acid-sensitive O-phosphodiester-linked glycan modifications, of CPBF8. We further showed that the repression of CPBF8 by gene silencing reduced the lysozyme and β-hexosaminidase activity in phagosomes and delayed the degradation of C. perfringens. Repression of CPBF8 also resulted in decrease in the cytopathy against the mammalian cells, suggesting that CPBF8 may also be involved in, besides the degradation of ingested bacteria, the pathogenesis against the mammalian hosts. This work represents the first case of the identification of a transport receptor of hydrolytic enzymes responsible for the degradation of microorganisms in phagosomes.

  5. PtdIns(4,5)P2 and PtdIns3P coordinate to regulate phagosomal sealing for apoptotic cell clearance

    PubMed Central

    Cheng, Shiya; Wang, Kun; Zou, Wei; Miao, Rui; Huang, Yaling; Wang, Haibin

    2015-01-01

    Phagocytosis requires phosphoinositides (PIs) as both signaling molecules and localization cues. How PIs coordinate to control phagosomal sealing and the accompanying switch of organelle identity is unclear. In this study, we followed dynamic changes in PIs during apoptotic cell clearance in Caenorhabditis elegans. We found that phosphatidylinositol-4,5-bisphosphate (PtdIns(4,5)P2) and phosphatidylinositol-3-phosphate (PtdIns3P), which accumulate transiently on unsealed and fully sealed phagosomes, respectively, are both involved in phagosome closure. We identified PtdIns3P phosphatase MTM-1 as an effector of PtdIns(4,5)P2 to promote phagosomal sealing. MTM-1 coordinates with the class II PI3 kinase PIKI-1 to control PtdIns3P levels on unsealed phagosomes. The SNX9 family protein LST-4 is required for sealing, and its association with unsealed phagosomes is regulated by PtdIns(4,5)P2, PIKI-1, and MTM-1. Loss of LST-4 or its retention on phagosomes disrupts sealing and suppresses PtdIns3P accumulation, indicating close coupling of the two events. Our findings support a coincidence detection mechanism by which phagosomal sealing is regulated and coupled with conversion from PtdIns(4,5)P2 enrichment on unsealed phagosomes to PtdIns3P enrichment on fully sealed phagosomes. PMID:26240185

  6. Cysteine protease-binding protein family 6 mediates the trafficking of amylases to phagosomes in the enteric protozoan Entamoeba histolytica.

    PubMed

    Furukawa, Atsushi; Nakada-Tsukui, Kumiko; Nozaki, Tomoyoshi

    2013-05-01

    Phagocytosis plays a pivotal role in nutrient acquisition and evasion from the host defense systems in Entamoeba histolytica, the intestinal protozoan parasite that causes amoebiasis. We previously reported that E. histolytica possesses a unique class of a hydrolase receptor family, designated the cysteine protease-binding protein family (CPBF), that is involved in trafficking of hydrolases to lysosomes and phagosomes, and we have also reported that CPBF1 and CPBF8 bind to cysteine proteases or β-hexosaminidase α-subunit and lysozymes, respectively. In this study, we showed by immunoprecipitation that CPBF6, one of the most highly expressed CPBF proteins, specifically binds to α-amylase and γ-amylase. We also found that CPBF6 is localized in lysosomes, based on immunofluorescence imaging. Immunoblot and proteome analyses of the isolated phagosomes showed that CPBF6 mediates transport of amylases to phagosomes. We also demonstrated that the carboxyl-terminal cytosolic region of CPBF6 is engaged in the regulation of the trafficking of CPBF6 to phagosomes. Our proteome analysis of phagosomes also revealed new potential phagosomal proteins.

  7. Repeated Cycles of Rapid Actin Assembly and Disassembly on Epithelial Cell PhagosomesV⃞

    PubMed Central

    Yam, Patricia T.; Theriot, Julie A.

    2004-01-01

    We have found that early in infection of the intracellular pathogen Listeria monocytogenes in Madin-Darby canine kidney epithelial cells expressing actin conjugated to green fluorescent protein, F-actin rapidly assembles (∼25 s) and disassembles (∼30 s) around the bacteria, a phenomenon we call flashing. L. monocytogenes strains unable to perform actin-based motility or unable to escape the phagosome were capable of flashing, suggesting that the actin assembly occurs on the phagosome membrane. Cycles of actin assembly and disassembly could occur repeatedly on the same phagosome. Indirect immunofluorescence showed that most bacteria were fully internalized when flashing occurred, suggesting that actin flashing does not represent phagocytosis. Escherichia coli expressing invA, a gene product from Yersinia pseudotuberculosis that mediates cellular invasion, also induced flashing. Furthermore, polystyrene beads coated with E-cadherin or transferrin also induced flashing after internalization. This suggests that flashing occurs downstream of several distinct molecular entry mechanisms and may be a general consequence of internalization of large objects by epithelial cells. PMID:15456901

  8. Transcriptional Adaptation of Mycobacterium tuberculosis within Macrophages: Insights into the Phagosomal Environment.

    PubMed

    Schnappinger, Dirk; Ehrt, Sabine; Voskuil, Martin I; Liu, Yang; Mangan, Joseph A; Monahan, Irene M; Dolganov, Gregory; Efron, Brad; Butcher, Philip D; Nathan, Carl; Schoolnik, Gary K

    2003-09-01

    Little is known about the biochemical environment in phagosomes harboring an infectious agent. To assess the state of this organelle we captured the transcriptional responses of Mycobacterium tuberculosis (MTB) in macrophages from wild-type and nitric oxide (NO) synthase 2-deficient mice before and after immunologic activation. The intraphagosomal transcriptome was compared with the transcriptome of MTB in standard broth culture and during growth in diverse conditions designed to simulate features of the phagosomal environment. Genes expressed differentially as a consequence of intraphagosomal residence included an interferon gamma- and NO-induced response that intensifies an iron-scavenging program, converts the microbe from aerobic to anaerobic respiration, and induces a dormancy regulon. Induction of genes involved in the activation and beta-oxidation of fatty acids indicated that fatty acids furnish carbon and energy. Induction of sigmaE-dependent, sodium dodecyl sulfate-regulated genes and genes involved in mycolic acid modification pointed to damage and repair of the cell envelope. Sentinel genes within the intraphagosomal transcriptome were induced similarly by MTB in the lungs of mice. The microbial transcriptome thus served as a bioprobe of the MTB phagosomal environment, showing it to be nitrosative, oxidative, functionally hypoxic, carbohydrate poor, and capable of perturbing the pathogen's cell envelope.

  9. Glutamate Utilization Couples Oxidative Stress Defense and the Tricarboxylic Acid Cycle in Francisella Phagosomal Escape

    PubMed Central

    Ramond, Elodie; Gesbert, Gael; Rigard, Mélanie; Dairou, Julien; Dupuis, Marion; Dubail, Iharilalao; Meibom, Karin; Henry, Thomas; Barel, Monique; Charbit, Alain

    2014-01-01

    Intracellular bacterial pathogens have developed a variety of strategies to avoid degradation by the host innate immune defense mechanisms triggered upon phagocytocis. Upon infection of mammalian host cells, the intracellular pathogen Francisella replicates exclusively in the cytosolic compartment. Hence, its ability to escape rapidly from the phagosomal compartment is critical for its pathogenicity. Here, we show for the first time that a glutamate transporter of Francisella (here designated GadC) is critical for oxidative stress defense in the phagosome, thus impairing intra-macrophage multiplication and virulence in the mouse model. The gadC mutant failed to efficiently neutralize the production of reactive oxygen species. Remarkably, virulence of the gadC mutant was partially restored in mice defective in NADPH oxidase activity. The data presented highlight links between glutamate uptake, oxidative stress defense, the tricarboxylic acid cycle and phagosomal escape. This is the first report establishing the role of an amino acid transporter in the early stage of the Francisella intracellular lifecycle. PMID:24453979

  10. Modulation of phenotypic and functional maturation of dendritic cells by intestinal bacteria and gliadin: relevance for celiac disease.

    PubMed

    De Palma, G; Kamanova, J; Cinova, J; Olivares, M; Drasarova, H; Tuckova, L; Sanz, Y

    2012-11-01

    DC maturation and functions are influenced by microbial and environmental stimuli, which could contribute to immune dysfunction. Here, we have investigated the role of enterobacteria (Escherichia coli CBL2 and Shigella CBD8) isolated from CD patients, bifidobacteria (Bifidobacterium longum CECT 7347 and Bifidobacterium bifidum CECT 7365), and gliadins on phenotypic and functional features of MDDCs and in coculture with Caco-2 cells. The ultimate goal of our study is to understand the roles played by specific components of the gut microbiota in CD. Enterobacteria induced marked alterations in MDDC morphology, inducing podosome dissolution and dendrites, and activated MDDC adhesion and spreading. Enterobacteria also induced inflammatory cytokine production (IFN-γ, TNF-α, and IL-12), partially resembling the gliadin-induced Th1-type cytokine profile. B. longum CECT 7347 and B. bifidum CECT 7365 induced minor MDDC morphological changes and activated adhesion and spreading and inflammatory cytokine production to a lesser extent compared with enterobacteria. B. longum CECT 7347 also induced lower CD86 and CD40 expression on MDDCs than the two enterobacteria. The aforementioned bifidobacterial strain also reduced gliadin-induced IFN-γ production and increased IL-10 secretion when both stimuli were combined. Similar trends were detected for MDDCs cocultured with Caco-2 cells. B. longum CECT 7347 reversed the gliadin-reduced ZO-1 expression in Caco-2 cells. Thus, our results suggest that specific components of the gut microbiota may influence phenotypic and functional maturation of DCs differently and their interactions with epithelial cells. This could ultimately define the role of DCs in CD progression.

  11. Mapping-by-Sequencing Identifies HvPHYTOCHROME C as a Candidate Gene for the early maturity 5 Locus Modulating the Circadian Clock and Photoperiodic Flowering in Barley

    PubMed Central

    Pankin, Artem; Campoli, Chiara; Dong, Xue; Kilian, Benjamin; Sharma, Rajiv; Himmelbach, Axel; Saini, Reena; Davis, Seth J; Stein, Nils; Schneeberger, Korbinian; von Korff, Maria

    2014-01-01

    Phytochromes play an important role in light signaling and photoperiodic control of flowering time in plants. Here we propose that the red/far-red light photoreceptor HvPHYTOCHROME C (HvPHYC), carrying a mutation in a conserved region of the GAF domain, is a candidate underlying the early maturity 5 locus in barley (Hordeum vulgare L.). We fine mapped the gene using a mapping-by-sequencing approach applied on the whole-exome capture data from bulked early flowering segregants derived from a backcross of the Bowman(eam5) introgression line. We demonstrate that eam5 disrupts circadian expression of clock genes. Moreover, it interacts with the major photoperiod response gene Ppd-H1 to accelerate flowering under noninductive short days. Our results suggest that HvPHYC participates in transmission of light signals to the circadian clock and thus modulates light-dependent processes such as photoperiodic regulation of flowering. PMID:24996910

  12. 5-Aza-2'-deoxycytidine acts as a modulator of chondrocyte hypertrophy and maturation in chick caudal region chondrocytes in culture

    PubMed Central

    2016-01-01

    This study was carried out to explore the effect of DNA hypomethylation on chondrocytes phenotype, in particular the effect on chondrocyte hypertrophy, maturation, and apoptosis. Chondrocytes derived from caudal region of day 17 embryonic chick sterna were pretreated with hypomethylating drug 5-aza-2'-deoxycytidine for 48 hours and then maintained in the normal culture medium for up to 14 days. Histological studies showed distinct morphological changes occurred in the pretreated cultures when compared to the control cultures. The pretreated chondrocytes after 7 days in culture became bigger in size and acquired more flattened fibroblastic phenotype as well as a loss of cartilage specific extracellular matrix. Scanning electron microscopy at day 7 showed chondrocytes to have increased in cell volume and at day 14 in culture the extracellular matrix of the pretreated cultures showed regular fibrillar structure heavily embedded with matrix vesicles, which is the characteristic feature of chondrocyte hypertrophy. Transmission electron microscopic studies indicated the terminal fate of the hypertrophic cells in culture. The pretreated chondrocytes grown for 14 days in culture showed two types of cells: dark cells which had condense chromatin in dark patches and dark cytoplasm. The other light chondrocytes appeared to be heavily loaded with endoplasmic reticulum indicative of very active protein and secretory activity; their cytoplasm had large vacuoles and disintegrating cytoplasm. The biosynthetic profile showed that the pretreated cultures were actively synthesizing and secreting type X collagen and alkaline phosphatase as a major biosynthetic product. PMID:27382512

  13. Oleoresinosis in Grand Fir (Abies grandis) Saplings and Mature Trees (Modulation of this Wound Response by Light and Water Stresses).

    PubMed Central

    Lewinsohn, E.; Gijzen, M.; Muzika, R. M.; Barton, K.; Croteau, R.

    1993-01-01

    The stem content of diterpene resin acids (rosin) increases dramatically following wounding of grand fir (Abies grandis) saplings, but the level of monoterpene olefins (turpentine) in the stem decreases following injury, in spite of a significant increase in monoterpene cyclase (synthase) activity. However, this observation was explained when rapid evaporative losses of the volatile monoterpenes from the wound site was demonstrated by trapping experiments, a finding consistent with a role of turpentine as a solvent for the mobilization and deposition of rosin to seal the injury. Mature forest trees responded to stem wounding by the enhancement of monoterpene cyclization capacity in a manner similar to 2-year-old grand fir saplings raised in the greenhouse. Light and water stresses greatly reduced the constitutive level of monoterpene cyclase activity and abolished the wound-induced response. The diminution in monoterpene biosynthetic capacity was correlated with a dramatic decrease in cyclase protein as demonstrated by immunoblotting. Relief of stress conditions resulted in the restoration of cyclase activity (both constitutive and wound induced) to control levels. The results of these experiments indicate that grand fir saplings are a suitable model for studies of the regulation of defensive oleoresinosis in conifers. PMID:12231755

  14. Phosphoinositides regulate membrane-dependent actin assembly by latex bead phagosomes.

    PubMed

    Defacque, Hélène; Bos, Evelyne; Garvalov, Boyan; Barret, Cécile; Roy, Christian; Mangeat, Paul; Shin, Hye-Won; Rybin, Vladimir; Griffiths, Gareth

    2002-04-01

    Actin assembly on membrane surfaces is an elusive process in which several phosphoinositides (PIPs) have been implicated. We have reconstituted actin assembly using a defined membrane surface, the latex bead phagosome (LBP), and shown that the PI(4,5)P(2)-binding proteins ezrin and/or moesin were essential for this process (). Here, we provide several lines of evidence that both preexisting and newly synthesized PI(4,5)P(2), and probably PI(4)P, are essential for phagosomal actin assembly; only these PIPs were routinely synthesized from ATP during in vitro actin assembly. Treatment of LBP with phospholipase C or with adenosine, an inhibitor of type II PI 4-kinase, as well as preincubation with anti-PI(4)P or anti-PI(4,5)P(2) antibodies all inhibited this process. Incorporation of extra PI(4)P or PI(4,5)P(2) into the LBP membrane led to a fivefold increase in the number of phagosomes that assemble actin. An ezrin mutant mutated in the PI(4,5)P(2)-binding sites was less efficient in binding to LBPs and in reconstituting actin assembly than wild-type ezrin. Our data show that PI 4- and PI 5-kinase, and under some conditions also PI 3-kinase, activities are present on LBPs and can be activated by ATP, even in the absence of GTP or cytosolic components. However, PI 3-kinase activity is not required for actin assembly, because the process was not affected by PI 3-kinase inhibitors. We suggest that the ezrin-dependent actin assembly on the LBP membrane may require active turnover of D4 and D5 PIPs on the organelle membrane.

  15. Role of inhibin and activin in the modulation of gonadotropin- and steroid-induced oocyte maturation in the teleost Fundulus heteroclitus

    PubMed Central

    Petrino, Teresa R; Toussaint, Gesulla; Lin, Yu-Wai P

    2007-01-01

    demonstrate the presence of activin/inhibin subunits in the ovary of F. heteroclitus, these in vitro findings indicate that inhibin and activin are local regulators in the teleost ovary and have opposing effects in modulating oocyte maturation. PMID:17550604

  16. TLR3-Induced Maturation of Murine Dendritic Cells Regulates CTL Responses by Modulating PD-L1 Trafficking

    PubMed Central

    Varthaman, Aditi; Moreau, Hélène D.; Maurin, Mathieu; Benaroch, Philippe

    2016-01-01

    Targeting TLR3 through formulations of polyI:C is widely studied as an adjuvant in cancer immunotherapy. The efficacy of such targeting has been shown to increase in combination with anti-PD-L1 treatment. Nevertheless, the mechanistic details of the effect of polyI:C on DC maturation and the impact on T-DC interactions upon PD-L1 blockade is largely unknown. Here we found that although DC treatment with polyI:C induced a potent inflammatory response including the production of type I interferon, polyI:C treatment of DCs impaired activation of peptide specific CD8+ T cells mainly due to PD-L1. Interestingly, we found that PD-L1 trafficking to the cell surface is regulated in two waves in polyI:C-treated DCs. One induced upon overnight treatment and a second more rapid one, specific to polyI:C treatment, was induced upon CD40 signaling leading to a further increase in surface PD-L1 in DCs. The polyI:C-induced cell surface PD-L1 reduced the times of contact between DCs and T cells, potentially accounting for limited T cell activation. Our results reveal a novel CD40-dependent regulation of PD-L1 trafficking induced upon TLR3 signaling that dictates its inhibitory activity. These results provide a mechanistic framework to understand the efficacy of anti-PD-L1 cancer immunotherapy combined with TLR agonists. PMID:27911948

  17. Sexual maturation modulates expression of nuclear receptor types in laser-captured single cells of the cichlid (Oreochromis niloticus) pituitary.

    PubMed

    Kitahashi, Takashi; Ogawa, Satoshi; Soga, Tomoko; Sakuma, Yasuo; Parhar, Ishwar

    2007-12-01

    The role of steroid/thyroid hormones in the regulation of endocrine cells at the level of the pituitary has remained unclear. Therefore, using single-cell quantitative real-time PCR, we examined absolute amounts of transcripts for nuclear receptors [estrogen receptors (ERs) alpha, beta, and gamma; androgen receptors (ARs) a and b; glucocorticoid receptors (GRs) 1, 2a, and 2b; and thyroid hormone receptors (TRs) alpha1, alpha2, and beta] in pituitary cells of immature (IM) and mature (M) male tilapia, Oreochromis niloticus. In the two reproductive stages, ACTH cells expressed only ERbeta, whereas all other pituitary cell types expressed ERalpha + beta, and a subpopulation coexpressed ARa, ARb, GR1, GR2b, and TRbeta but lacked ERgamma, GR2a, TRalpha1, and TRalpha2. IM males had high percentages of LH cells (IM 46.0% vs. M 10.0%), GH cells (IM 23.3% vs. M 7.9%), and prolactin cells (IM 68.8% vs. M 6.0%) with ERbeta, and TSH cells (IM 19.2% vs. M 0.0%) and MSH cells (IM 25.6% vs. M 0.0%) with ERalpha + TRbeta. A high percentage of FSH cells in IM males expressed ERbeta (IM 46.9% vs. M 18.8%), and FSH cells in M males showed significantly high GR1 transcripts (IM 76.0 +/- 5.0 vs. M 195.0 +/- 10.7 copies per cell; P < 0.05), suggesting that FSH cells are regulated differently in the two reproductive stages. Coexpression of ERalpha + beta in high percentages of cells of the GH family (GH, IM 43.8% vs. M 14.3%; prolactin, IM 8.3% vs. M 59.7%; somatolactin, IM 22.2% vs. M 42.2%) suggests that the expression of both ERs is important for functionality. Thus, differential coexpression of genes for nuclear receptors in subpopulations of pituitary cell types suggests multiple steroid/thyroid hormone regulatory pathways at the level of the pituitary during the two reproductive stages.

  18. Targeted Protein Degradation by Salmonella under Phagosome-Mimicking Culture Conditions Investigated Using Comparative Peptidomics

    SciTech Connect

    Manes, Nathan P.; Gustin, Jean K.; Rue, Joanne; Mottaz, Heather M.; Purvine, Samuel O.; Norbeck, Angela D.; Monroe, Matthew E.; Zimmer, Jennifer S.; Metz, Thomas O.; Adkins, Joshua N.; Smith, Richard D.; Heffron, Fred

    2007-04-01

    The pathogen Salmonella enterica is known to cause both food poisoning and typhoid fever. Due to the emergence of antibiotic-resistant isolates and the threat of bioterrorism (e.g., contamination of the food supply), there is a growing need to study this bacterium. In this investigation, comparative peptidomics was used to study Salmonella enterica serovar Typhimurium cultured in either a rich medium or in an acidic, low magnesium, and minimal nutrient medium designed to roughly mimic the macrophage phagosomal compartment (within which Salmonella are known to survive). Native peptides from cleared cell lysates were enriched by using isopropanol extraction and analyzed by using both LC-MS/MS and LC-FTICR-MS. We identified 5,163 distinct peptides originating from 682 proteins and the data clearly indicated that compared to cells cultured in the rich medium, Salmonella cultured in the phagosome-mimicking medium had dramatically higher abundances of a wide variety of protein degradation products, especially from ribosomal proteins. Salmonella from the same cultures were also analyzed by using bottom-up proteomics, and when the peptidomic and proteomic data were analyzed together, two clusters of proteins targeted for proteolysis were tentatively identified. Possible roles of targeted proteolysis by phagocytosed Salmonella are discussed.

  19. Importance of Host Cell Arginine Uptake in Francisella Phagosomal Escape and Ribosomal Protein Amounts*

    PubMed Central

    Ramond, Elodie; Gesbert, Gael; Guerrera, Ida Chiara; Chhuon, Cerina; Dupuis, Marion; Rigard, Mélanie; Henry, Thomas; Barel, Monique; Charbit, Alain

    2015-01-01

    Upon entry into mammalian host cells, the pathogenic bacterium Francisella must import host cell arginine to multiply actively in the host cytoplasm. We identified and functionally characterized an arginine transporter (hereafter designated ArgP) whose inactivation considerably delayed bacterial phagosomal escape and intracellular multiplication. Intramacrophagic growth of the ΔargP mutant was fully restored upon supplementation of the growth medium with excess arginine, in both F. tularensis subsp. novicida and F. tularensis subsp. holarctica LVS, demonstrating the importance of arginine acquisition in these two subspecies. High-resolution mass spectrometry revealed that arginine limitation reduced the amount of most of the ribosomal proteins in the ΔargP mutant. In response to stresses such as nutritional limitation, repression of ribosomal protein synthesis has been observed in all kingdoms of life. Arginine availability may thus contribute to the sensing of the intracellular stage of the pathogen and to trigger phagosomal egress. All MS data have been deposited in the ProteomeXchange database with identifier PXD001584 (http://proteomecentral.proteomexchange.org/dataset/PXD001584). PMID:25616868

  20. Phagosomal degradation increases TLR access to bacterial ligands and enhances macrophage sensitivity to bacteria

    PubMed Central

    Wolf, Andrea J.; Arruda, Andrea; Reyes, Christopher N.; Kaplan, Amber T.; Shimada, Takahiro; Shimada, Kenichi; Arditi, Moshe; Liu, George; Underhill, David M.

    2011-01-01

    Signaling by innate immune receptors initiates and orchestrates the overall immune responses to infection. Macrophage receptors recognizing pathogens can be broadly grouped into surface receptors and receptors restricted to intracellular compartments, such as phagosomes and the cytoplasm. There is an expectation that ingestion and degradation of microorganisms by phagocytes contributes to activation of intracellular innate receptors, although direct demonstrations of this are rare and many model ligands are studied in soluble form, outside of their microbial context. By comparing a wild-type strain of Staphylococcus aureus and a lysozyme-sensitive mutant, we have been able to directly address the role of degradation of live bacteria by mouse macrophages in determining the overall innate cellular inflammatory response. Our investigations revealed a biphasic response to S. aureus that consisted of an initial signal resulting from the engagement of surface TLR2, followed by a later, second wave on inflammatory gene induction. This second wave of inflammatory signaling was dependent on and correlated with the timing of bacterial degradation in phagosomes. We found that TLR2 signaling followed by TLR2/TLR9 signaling enhanced sensitivity to small numbers of bacteria. We further found that treating wild-type bacteria with the peptidoglycan synthesis-inhibiting antibiotic vancomycin made S. aureus more susceptible to degradation and resulted in increased inflammatory responses, similar to those observed for mutant degradation-sensitive bacteria. PMID:22031762

  1. A small molecule deubiquitinase inhibitor increases localization of inducible nitric oxide synthase to the macrophage phagosome and enhances bacterial killing.

    PubMed

    Burkholder, Kristin M; Perry, Jeffrey W; Wobus, Christiane E; Donato, Nicholas J; Showalter, Hollis D; Kapuria, Vaibhav; O'Riordan, Mary X D

    2011-12-01

    Macrophages are key mediators of antimicrobial defense and innate immunity. Innate intracellular defense mechanisms can be rapidly regulated at the posttranslational level by the coordinated addition and removal of ubiquitin by ubiquitin ligases and deubiquitinases (DUBs). While ubiquitin ligases have been extensively studied, the contribution of DUBs to macrophage innate immune function is incompletely defined. We therefore employed a small molecule DUB inhibitor, WP1130, to probe the role of DUBs in the macrophage response to bacterial infection. Treatment of activated bone marrow-derived macrophages (BMM) with WP1130 significantly augmented killing of the intracellular bacterial pathogen Listeria monocytogenes. WP1130 also induced killing of phagosome-restricted bacteria, implicating a bactericidal mechanism associated with the phagosome, such as the inducible nitric oxide synthase (iNOS). WP1130 had a minimal antimicrobial effect in macrophages lacking iNOS, indicating that iNOS is an effector mechanism for WP1130-mediated bacterial killing. Although overall iNOS levels were not notably different, we found that WP1130 significantly increased colocalization of iNOS with the Listeria-containing phagosome during infection. Taken together, our data indicate that the deubiquitinase inhibitor WP1130 increases bacterial killing in macrophages by enhancing iNOS localization to the phagosome and suggest a potential role for ubiquitin regulation in iNOS trafficking.

  2. The ability of Listeria monocytogenes PI-PLC to facilitate escape from the macrophage phagosome is dependent on host PKCbeta.

    PubMed

    Poussin, Mathilde A; Leitges, Michael; Goldfine, Howard

    2009-01-01

    Listeria monocytogenes are facultative intracellular pathogenic bacteria that can infect macrophages as well as non-professional phagocytes. After entry in the host cell, the bacteria escape from the phagosome into the cytoplasm. In murine macrophages and in cell lines derived from these cells, escape of L. monocytogenes from the phagosome is absolutely dependent on listeriolysin O (LLO) and facilitated by a secreted phosphatidylinositol-specific phospholipase C (PI-PLC). Work in this laboratory has previously demonstrated a LLO and PI-PLC-dependent translocation of host PKCbeta isoforms. Pharmacological inhibition of PKCbeta resulted in a significant reduction in permeabilization of the phagosome, and in the number of bacteria reaching the cytosol. These findings led to the prediction that the bacterial PI-PLC promotes escape through the production of diacylglycerol leading to the activation of host PKCbeta. To test this hypothesis, bone marrow-derived macrophages (BMMf) obtained from PKCbeta knockout (PKCbetaKO) or C57Bl/6 mice were infected with L. monocytogenes. We observed that wild-type L. monocytogenes escapes from the phagosome of PKCbetaKO BMMf as well as from C57Bl/6 BMMf. However, in PKCbetaKO BMMf, L. monocytogenes uses a PI-PLC-independent, but phosphatidylcholine-preferring PLC (PC-PLC)-dependent pathway to facilitate escape. These findings strongly support the hypothesis that PI-PLC promotes escape through mobilization of host PKCbeta.

  3. Effects of zinc oxide nanoparticles on Kupffer cell phagosomal motility, bacterial clearance, and liver function

    PubMed Central

    Watson, Christa Y; Molina, Ramon M; Louzada, Andressa; Murdaugh, Kimberly M; Donaghey, Thomas C; Brain, Joseph D

    2015-01-01

    Background Zinc oxide engineered nanoparticles (ZnO ENPs) have potential as nanomedicines due to their inherent properties. Studies have described their pulmonary impact, but less is known about the consequences of ZnO ENP interactions with the liver. This study was designed to describe the effects of ZnO ENPs on the liver and Kupffer cells after intravenous (IV) administration. Materials and methods First, pharmacokinetic studies were conducted to determine the tissue distribution of neutron-activated 65ZnO ENPs post-IV injection in Wistar Han rats. Then, a noninvasive in vivo method to assess Kupffer cell phagosomal motility was employed using ferromagnetic iron particles and magnetometry. We also examined whether prior IV injection of ZnO ENPs altered Kupffer cell bactericidal activity on circulating Pseudomonas aeruginosa. Serum and liver tissues were collected to assess liver-injury biomarkers and histological changes, respectively. Results We found that the liver was the major site of initial uptake of 65ZnO ENPs. There was a time-dependent decrease in tissue levels of 65Zn in all organs examined, refecting particle dissolution. In vivo magnetometry showed a time-dependent and transient reduction in Kupffer cell phagosomal motility. Animals challenged with P. aeruginosa 24 hours post-ZnO ENP injection showed an initial (30 minutes) delay in vascular bacterial clearance. However, by 4 hours, IV-injected bacteria were cleared from the blood, liver, spleen, lungs, and kidneys. Seven days post-ZnO ENP injection, creatine phosphokinase and aspartate aminotransferase levels in serum were significantly increased. Histological evidence of hepatocyte damage and marginated neutrophils were observed in the liver. Conclusion Administration of ZnO ENPs transiently inhibited Kupffer cell phagosomal motility and later induced hepatocyte injury, but did not alter bacterial clearance from the blood or killing in the liver, spleen, lungs, or kidneys. Our data show that

  4. The unique trafficking pattern of Salmonella typhimurium-containing phagosomes in murine macrophages is independent of the mechanism of bacterial entry.

    PubMed Central

    Rathman, M; Barker, L P; Falkow, S

    1997-01-01

    Although it has been known for some time that Salmonella typhimurium is able to survive and even replicate in the normally bactericidal environment of the macrophage phagosome, the mechanisms by which this organism accomplishes this feat remain obscure. In this study, a murine macrophage cell line and confocal immunofluorescence microscopy were used to more thoroughly define the specific nature of phagosomes containing latex beads or wild-type S. typhimurium (viable or heat-killed organisms). Live S. typhimurium organisms were observed to reside in phagosomes that diverge from the degradative pathway of the macrophage. These compartments contain lysosomal glycoproteins and lysosomal acid phosphatase, endocytic markers delivered to vacuoles by mannose 6-phosphate receptor-independent mechanisms, but are devoid of the mannose 6-phosphate receptor and cathepsin L. In contrast, phagosomes containing latex beads or heat-killed organisms appeared to be processed along the degradative pathway of the host cell; these compartments colocalized not only with lysosomal glycoproteins and lysosomal acid phosphatases but also with mannose 6-phosphate receptors and cathepsin L. The uniqueness of the phagosome containing viable S. typhimurium was confirmed by the observation that these compartments, in comparison to phagosomes containing latex beads, do not readily interact with incoming endocytic traffic. Finally, we show that an isogenic, noninvasive mutant of S. typhimurium, BJ66, ends up in an intracellular compartment identical to the wild-type S. typhimurium-containing phagosome. Thus, modifications of the Salmonella-containing compartment occur independently of the mechanism of bacterial entry. PMID:9119490

  5. Atg8 is involved in endosomal and phagosomal acidification in the parasitic protist E ntamoeba histolytica

    PubMed Central

    Picazarri, Karina; Nakada‐Tsukui, Kumiko; Tsuboi, Kumiko; Miyamoto, Eri; Watanabe, Naoko; Kawakami, Eiryo

    2015-01-01

    Summary Autophagy is one of two major bulk protein degradation systems and is conserved throughout eukaryotes. The protozoan E ntamoeba histolytica, which is a human intestinal parasite, possesses a restricted set of autophagy‐related (Atg) proteins compared with other eukaryotes and thus represents a suitable model organism for studying the minimal essential components and ancestral functions of autophagy. E. histolytica possesses two conjugation systems: Atg8 and Atg5/12, although a gene encoding Atg12 is missing in the genome. Atg8 is considered to be the central and authentic marker of autophagosomes, but recent studies have demonstrated that Atg8 is not exclusively involved in autophagy per se, but other fundamental mechanisms of vesicular traffic. To investigate this question in E . histolytica, we studied on Atg8 during the proliferative stage. Atg8 was constitutively expressed in both laboratory‐maintained and recently established clinical isolates and appeared to be lipid‐modified in logarithmic growth phase, suggesting a role of Atg8 in non‐stress and proliferative conditions. These findings are in contrast to those for E ntamoeba invadens, in which autophagy is markedly induced during an early phase of differentiation from the trophozoite into the cyst. The repression of Atg8 gene expression in En . histolytica by antisense small RNA‐mediated transcriptional gene silencing resulted in growth retardation, delayed endocytosis and reduced acidification of endosomes and phagosomes. Taken together, these results suggest that Atg8 and the Atg8 conjugation pathway have some roles in the biogenesis of endosomes and phagosomes in this primitive eukaryote. PMID:25923949

  6. Atg8 is involved in endosomal and phagosomal acidification in the parasitic protist Entamoeba histolytica.

    PubMed

    Picazarri, Karina; Nakada-Tsukui, Kumiko; Tsuboi, Kumiko; Miyamoto, Eri; Watanabe, Naoko; Kawakami, Eiryo; Nozaki, Tomoyoshi

    2015-10-01

    Autophagy is one of two major bulk protein degradation systems and is conserved throughout eukaryotes. The protozoan Entamoeba histolytica, which is a human intestinal parasite, possesses a restricted set of autophagy-related (Atg) proteins compared with other eukaryotes and thus represents a suitable model organism for studying the minimal essential components and ancestral functions of autophagy. E. histolytica possesses two conjugation systems: Atg8 and Atg5/12, although a gene encoding Atg12 is missing in the genome. Atg8 is considered to be the central and authentic marker of autophagosomes, but recent studies have demonstrated that Atg8 is not exclusively involved in autophagy per se, but other fundamental mechanisms of vesicular traffic. To investigate this question in E. histolytica, we studied on Atg8 during the proliferative stage. Atg8 was constitutively expressed in both laboratory-maintained and recently established clinical isolates and appeared to be lipid-modified in logarithmic growth phase, suggesting a role of Atg8 in non-stress and proliferative conditions. These findings are in contrast to those for Entamoeba invadens, in which autophagy is markedly induced during an early phase of differentiation from the trophozoite into the cyst. The repression of Atg8 gene expression in En. histolytica by antisense small RNA-mediated transcriptional gene silencing resulted in growth retardation, delayed endocytosis and reduced acidification of endosomes and phagosomes. Taken together, these results suggest that Atg8 and the Atg8 conjugation pathway have some roles in the biogenesis of endosomes and phagosomes in this primitive eukaryote.

  7. Fatty acid composition of porcine cumulus oocyte complexes (COC) during maturation: effect of the lipid modulators trans-10, cis-12 conjugated linoleic acid (t10,c12 CLA) and forskolin.

    PubMed

    Prates, E G; Alves, S P; Marques, C C; Baptista, M C; Horta, A E M; Bessa, R J B; Pereira, R M

    2013-05-01

    The effect of maturation and of two lipid modulators supplementation along in vitro maturation (IVM) on fatty acid (FA) and dimethylacetal (DMA) composition of porcine cumulus oocyte complexes (COC) were studied. Abattoir-derived immature COC were analyzed for FA and DMA or submitted to IVM as follows: control group; t10,c12 CLA group, t10,c12 CLA supplementation for 44 h; Forskolin group, forskolin supplementation during the initial 2 h; t10,c12 CLA + forskolin group, t10,c12 CLA for 44 h and forskolin for just 2h. Each experimental group had five replicates. FA analysis of oocytes, cumulus cells (CC), follicular fluid, and culture media were performed by gas-liquid chromatography. Oocytes and their CC had different FA composition. Oocytes were richer in saturated FA (SFA) preferentially maintaining their FA profile during maturation. Mature CC had the highest polyunsaturated FA (PUFA) content. Five individual and total SFA, and monounsaturated FA (MUFA), notably oleic acid (c9-18:1), percentages were lower (P ≤ 0.023) in mature than in immature CC. t10,c12 CLA was accumulated by COC from t10,c12 CLA and t10,c12 CLA + forskolin groups, mostly in CC where MUFA and an eicosatrienoic isomer decreased (P ≤ 0.043). Nevertheless, PUFA or FA and DMA total content were not affected. Arachidonic acid was reduced in t10,c12 CLA + forskolin CC and hexadecanal-DMA-16:0 in t10,c12 CLA CC. Forskolin alone increased (P ≤ 0.043) c9-18:1 in oocytes. In conclusion, maturation process clearly changed porcine COC FA and DMA profiles, mostly of CC, also more susceptible to modifications induced by t10,c12 CLA. This possibility of manipulating COC lipid composition during IVM could be used to improve oocyte quality/cryopreservation efficiency.

  8. Brain maturation and epilepsy.

    PubMed

    Dulac, Olivier; Milh, Mathieu; Holmes, Gregory L

    2013-01-01

    At full term, both glutamate and gamma-amino-butyric acid (GABA) are excitatory; cortical synapses are beginning to appear, there is little myelin in the cerebral hemispheres, and long tracts hardly start to develop. Neonatal myoclonic encephalopathy can result from premature activation of N-methyl-D-aspartate (NMDA) transmission. Benign neonatal seizures and migrating partial seizures in infancy could involve excessive or premature excitability of deep cortical layers. Benign rolandic epilepsy and continuous spike waves in slow sleep are consistent with an excess of both excitatory and inhibitory cortical synapses. West and Lennox-Gastaut syndromes express age-related diffuse cortical hyperexcitability, the pattern depending on the age of occurrence; synchronization of spikes is becoming possible with maturation of the myelin. Idiopathic generalized epilepsy is itself modulated by maturation that causes frontal hyperexcitability generating myoclonic-astatic seizures, between the ages of infantile and juvenile myoclonic epilepsies. Physiological delay of hippocampo-neocortical pathways maturation could account for the delayed occurrence of mesial temporal epilepsy following infantile damage, whereas premature maturation could contribute to fronto-temporal damage characteristic of fever-induced epileptic encephalopathy in school-age children, a dramatic school-age epileptic encephalopathy.

  9. Phagosome-lysosome fusions in macrophages infected by Mycobacterium avium: role of mycosides-C and other cells surface components.

    PubMed

    Fréhel, C; Rastogi, N

    1989-01-01

    The phagosome-lysosome fusions (PLE) were assessed in case of bone-marrow macrophages infected by the opportunistic species Mycobacterium avium, employing the acid-phosphatase (AcPase) electron-cytochemistry. The role of surface components was evaluated by coating the bacteria prior to phagocytosis by specific M. avium antiserum or the anti-mycosides-C serum raised in rabbit. PLF was evaluated under the electron microscope during (2, 4 hours), or after (24 hours) phagocytosis. The preliminary results suggest that although M. avium surface components intervene in PLF inhibition, the role of mycosides-C among these surface components (effectively intervening in PLF inhibition) is questionable.

  10. Cytosolic Delivery of Liposomal Vaccines by Means of the Concomitant Photosensitization of Phagosomes.

    PubMed

    Hjálmsdóttir, Ásdís; Bühler, Céline; Vonwil, Vera; Roveri, Maurizio; Håkerud, Monika; Wäckerle-Men, Ying; Gander, Bruno; Johansen, Pål

    2016-02-01

    One of the greatest pharmaceutical challenges in vaccinology is the delivery of antigens to the cytosol of antigen-presenting cells (APCs) in order to allow for the stimulation of major histocompatibility complex (MHC) class I-restricted CD8(+) T-cell responses, which may act on intracellular infections or cancer. Recently, we described a novel method for cytotoxic T-lymphocyte (CTL) vaccination by combining antigens with a photosensitizer and light for cytosolic antigen delivery. The goal of the current project was to test this immunization method with particle-based formulations. Liposomes were prepared from dipalmitoylphosphatidylcholine and cholesterol, and the antigen ovalbumin (OVA) or the photosensitizer tetraphenyl chlorine disulfonate (TPCS2a) was separately encapsulated. C57BL/6 mice were immunized intradermally with OVA liposomes or a combination of OVA and TPCS2a liposomes, and light was applied the next day for activation of the photosensitizer resulting in cytosolic release of antigen from phagosomes. Immune responses were tested both after a prime only regime and after a prime-boost scheme with a repeat immunization 2 weeks post priming. Antigen-specific CD8(+) T-cell responses and antibody responses were analyzed ex vivo by flow cytometry and ELISA methods. The physicochemical stability of liposomes upon storage and light exposure was analyzed in vitro. Immunization with both TPCS2a- and OVA-containing liposomes greatly improved CD8(+) T-cell responses as compared to immunization without TPCS2a and as measured by proliferation in vivo and cytokine secretion ex vivo. In contrast, OVA-specific antibody responses (IgG1 and IgG2c) were reduced after immunization with TPCS2a-containing liposomes. The liposomal formulation protected the photosensitizer from light-induced inactivation during storage. In conclusion, the photosensitizer TPCS2a was successfully formulated in liposomes and enabled a shift from MHC class II to MHC class I antigen processing and

  11. Dictyostelium Nramp1, which is structurally and functionally similar to mammalian DMT1 transporter, mediates phagosomal iron efflux.

    PubMed

    Buracco, Simona; Peracino, Barbara; Cinquetti, Raffaella; Signoretto, Elena; Vollero, Alessandra; Imperiali, Francesca; Castagna, Michela; Bossi, Elena; Bozzaro, Salvatore

    2015-09-01

    The Nramp (Slc11) protein family is widespread in bacteria and eukaryotes, and mediates transport of divalent metals across cellular membranes. The social amoeba Dictyostelium discoideum has two Nramp proteins. Nramp1, like its mammalian ortholog (SLC11A1), is recruited to phagosomal and macropinosomal membranes, and confers resistance to pathogenic bacteria. Nramp2 is located exclusively in the contractile vacuole membrane and controls, synergistically with Nramp1, iron homeostasis. It has long been debated whether mammalian Nramp1 mediates iron import or export from phagosomes. By selectively loading the iron-chelating fluorochrome calcein in macropinosomes, we show that Dictyostelium Nramp1 mediates iron efflux from macropinosomes in vivo. To gain insight in ion selectivity and the transport mechanism, the proteins were expressed in Xenopus oocytes. Using a novel assay with calcein, and electrophysiological and radiochemical assays, we show that Nramp1, similar to rat DMT1 (also known as SLC11A2), transports Fe(2+) and manganese, not Fe(3+) or copper. Metal ion transport is electrogenic and proton dependent. By contrast, Nramp2 transports only Fe(2+) in a non-electrogenic and proton-independent way. These differences reflect evolutionary divergence of the prototypical Nramp2 protein sequence compared to the archetypical Nramp1 and DMT1 proteins.

  12. LIMP-2 Links Late Phagosomal Trafficking with the Onset of the Innate Immune Response to Listeria monocytogenes

    PubMed Central

    Carrasco-Marín, Eugenio; Fernández-Prieto, Lorena; Rodriguez-Del Rio, Estela; Madrazo-Toca, Fidel; Reinheckel, Thomas; Saftig, Paul; Alvarez-Dominguez, Carmen

    2011-01-01

    The innate immune response to Listeria monocytogenes depends on phagosomal bacterial degradation by macrophages. Here, we describe the role of LIMP-2, a lysosomal type III transmembrane glycoprotein and scavenger-like protein, in Listeria phagocytosis. LIMP-2-deficient mice display a macrophage-related defect in Listeria innate immunity. They produce less acute phase pro-inflammatory cytokines/chemokines, MCP-1, TNF-α, and IL-6 but normal levels of IL-12, IL-10, and IFN-γ and a 25-fold increase in susceptibility to Listeria infection. This macrophage defect results in a low listericidal potential, poor response to TNF-α activation signals, impaired phago-lysosome transformation into antigen-processing compartments, and uncontrolled LM cytosolic growth that fails to induce normal levels of acute phase pro-inflammatory cytokines. LIMP-2 transfection of CHO cells confirmed that LIMP-2 participates in the degradation of Listeria within phagosomes, controls the late endosomal/lysosomal fusion machinery, and is linked to the activation of Rab5a. Therefore, the role of LIMP-2 appears to be connected to the TNF-α-dependent and early activation of Listeria macrophages through internal signals linking the regulation of late trafficking events with the onset of the innate Listeria immune response. PMID:21123180

  13. Dental pulp in mature replanted human teeth: morphological alterations and metalloproteineses-2 and -9, Annexin-5, BCL-2 and iNOS modulation.

    PubMed

    Leone, A; Angelova Volponi, A; Uzzo, M L; Spatola, G F; Jurjus, A; Vandevska-Radunovic, V

    2015-01-01

    Tooth replantation, as a treatment concept, has been subject to controversies regarding the mechanism as well as the various parameters underlying this process. This work aimed to study time-related changes in the pulp of replanted mature human premolars through the changes in the levels of certain factors involved in the underlying mechanisms of pulpal tissue healing after replantation. Eleven experimental mature teeth were extracted, immediately replanted in the original socket and left without any other intervention for 1, 2, 3 and 12 weeks before re-extraction. Three premolars served as control. All specimens were subject to histological analysis and the levels of MMP-2, MMP-9, Annexin V, iNOS and BCL-2 (anti-apoptotic family) were analyzed employing immunohistochemistry. The results showed degradation of the extracellular matrix (ECM), inflammatory cell infiltrate, loss in pulpo-dentine interface and loss of odontoblasts in the dental pulp tissue. This was accompanied by increase over time of MMP-9, Annexin V, iNOS and a decrease of BCL-2 and MMP-2, suggesting that apoptosis increased throughout the experimental period.

  14. Modulation of cell-cycle dynamics is required to regulate the number of cerebellar GABAergic interneurons and their rhythm of maturation.

    PubMed

    Leto, Ketty; Bartolini, Alice; Di Gregorio, Alessandra; Imperiale, Daniele; De Luca, Annarita; Parmigiani, Elena; Filipkowski, Robert K; Kaczmarek, Leszek; Rossi, Ferdinando

    2011-08-01

    The progenitors of cerebellar GABAergic interneurons proliferate up to postnatal development in the prospective white matter, where they give rise to different neuronal subtypes, in defined quantities and according to precise spatiotemporal sequences. To investigate the mechanisms that regulate the specification of distinct interneuron phenotypes, we examined mice lacking the G1 phase-active cyclin D2. It has been reported that these mice show severe reduction of stellate cells, the last generated interneuron subtype. We found that loss of cyclin D2 actually impairs the whole process of interneuron genesis. In the mutant cerebella, progenitors of the prospective white matter show reduced proliferation rates and enhanced tendency to leave the cycle, whereas young postmitotic interneurons undergo severe delay of their maturation and migration. As a consequence, the progenitor pool is precociously exhausted and the number of interneurons is significantly reduced, although molecular layer interneurons are more affected than those of granular layer or deep nuclei. The characteristic inside-out sequence of interneuron placement in the cortical layers is also reversed, so that later born cells occupy deeper positions than earlier generated ones. Transplantation experiments show that the abnormalities of cyclin D2(-/-) interneurons are largely caused by cell-autonomous mechanisms. Therefore, cyclin D2 is not required for the specification of particular interneuron subtypes. Loss of this protein, however, disrupts regulatory mechanisms of cell cycle dynamics that are required to determine the numbers of interneurons of different types and impairs their rhythm of maturation and integration in the cerebellar circuitry.

  15. Vacuolar protein sorting protein 13A, TtVPS13A, localizes to the tetrahymena thermophila phagosome membrane and is required for efficient phagocytosis.

    PubMed

    Samaranayake, Haresha S; Cowan, Ann E; Klobutcher, Lawrence A

    2011-09-01

    Vacuolar protein sorting 13 (VPS13) proteins have been studied in a number of organisms, and mutations in VPS13 genes have been implicated in two human genetic disorders, but the function of these proteins is poorly understood. The TtVPS13A protein was previously identified in a mass spectrometry analysis of the Tetrahymena thermophila phagosome proteome (M. E. Jacobs et al., Eukaryot. Cell 5:1990-2000, 2006), suggesting that it is involved in phagocytosis. In this study, we analyzed the structure of the macronuclear TtVPS13A gene, which was found to be composed of 17 exons spanning 12.5 kb and was predicted to encode a protein of 3,475 amino acids (aa). A strain expressing a TtVPS13A-green fluorescent protein (GFP) fusion protein was constructed, and the protein was found to associate with the phagosome membrane during the entire cycle of phagocytosis. In addition, Tetrahymena cells with a TtVPS13A knockout mutation displayed impaired phagocytosis. Specifically, they grew slowly under conditions where phagocytosis is essential, they formed few phagosomes, and the digestion of phagosomal contents was delayed compared to wild-type cells. Overall, these results provide evidence that the TtVPS13A protein is required for efficient phagocytosis.

  16. The Role of Brain-Derived Neurotrophic Factor Receptors in the Mature Hippocampus: Modulation of Long-Term Potentiation through a Presynaptic Mechanism involving TrkB

    PubMed Central

    Xu, Baoji; Gottschalk, Wolfram; Chow, Ana; Wilson, Rachel I.; Schnell, Eric; Zang, Keling; Wang, Denan; Nicoll, Roger A.; Lu, Bai; Reichardt, Louis F.

    2009-01-01

    The neurotrophin BDNF has been shown to modulate long-term potentiation (LTP) at Schaffer collateral-CA1 hippocampal synapses. Mutants in the BDNF receptor gene trkB and antibodies to its second receptor p75NTR have been used to determine the receptors and cells involved in this response. Inhibition of p75NTR does not detectably reduce LTP or affect presynaptic function, but analyses of newly generated trkB mutants implicate TrkB. One mutant has reduced expression in a normal pattern of TrkB throughout the brain. The second mutant was created by cre-loxP-mediated removal of TrkB in CA1 pyramidal neurons of this mouse. Neither mutant detectably impacts survival or morphology of hippocampal neurons. TrkB reduction, however, affects presynaptic function and reduces the ability of tetanic stimulation to induce LTP. Postsynaptic glutamate receptors are not affected by TrkB reduction, indicating that BDNF does not modulate plasticity through postsynaptic TrkB. Consistent with this, elimination of TrkB in postsynaptic neurons does not affect LTP. Moreover, normal LTP is generated in the mutant with reduced TrkB by a depolarization–low-frequency stimulation pairing protocol that puts minimal demands on presynaptic terminal function. Thus, BDNF appears to act through TrkB presynaptically, but not postsynaptically, to modulate LTP. PMID:10995833

  17. An essential role of discoidin domain receptor 2 (DDR2) in osteoblast differentiation and chondrocyte maturation via modulation of Runx2 activation.

    PubMed

    Zhang, Yan; Su, Jin; Yu, Jiangtian; Bu, Xin; Ren, Tingting; Liu, Xinping; Yao, Libo

    2011-03-01

    Discoidin domain receptor 2 (DDR2) belongs to receptor tyrosine kinase (RTK) family and is activated by collagen binding. Although the bone defects in Ddr2 null mice have been reported for a decade, the molecular mechanism remains unclear. This study sought to investigate the function and detailed mechanism of DDR2 in osteogenic and chondrogenic differentiation. Herein we found that in preosteoblastic cells, DDR2 activation was enhanced by osteogenic induction but was not paralleled with the alteration of DDR2 expression. Under differentiated condition, downregulation of endogenous DDR2 through specific shRNA dramatically repressed osteoblastic marker gene expression and osteogenic differentiation. Enforced expression of constitutively activated DDR2 increased the expression of bone markers in both undifferentiated and differentiated osteoblasts. Importantly, molecular evidence showed that DDR2 regulated the transactivity of Runx2, a master transcription factor involved in skeletal development, by modulating its phosphorylation. Analysis of candidate protein kinases indicated that extracellular signal-regulated kinase (ERK) activation is responsive to DDR2 signaling and involved in DDR2 regulation of Runx2 phosphorylation and transcriptional activity. Notably, a gain-of-function mutant of Runx2 with enhanced ERK-independent phosphorylation rescued the impaired osteogenic phenotypes observed in Ddr2-silenced cells, whereas a Runx2 mutant devoid of phosphorylation regulation by ERK inhibited DDR2 induction of osteogenesis. In addition, DDR2 facilitated Runx2 transactivation and type X collagen expression in hypertrophic chondrocytes. Thus this study reveals for the first time that DDR2 plays an essential role in osteoblast and chondrocyte differentiation. The mechanism disclosure may provide therapeutic targets for human genetic disorders caused by DDR2 deficiency.

  18. Virulent Mycobacterium fortuitum Restricts NO Production by a Gamma Interferon-Activated J774 Cell Line and Phagosome-Lysosome Fusion

    PubMed Central

    da Silva, TÂnia Regina Marques; de Freitas, Juliana Ribeiro; Silva, Queilan Chagas; Figueira, Cláudio Pereira; Roxo, Eliana; Leão, Sylvia Cardoso; de Freitas, Luiz Antônio Rodrigues; Veras, Patrícia Sampaio Tavares

    2002-01-01

    The virulence of different isolates of Mycobacterium has been associated with two morphologically distinguishable colonial variants: opaque (SmOp) and transparent (SmTr). In this report we used an in vitro assay to compare macrophage (Mφ) responses to SmOp and SmTr Mycobacterium fortuitum variants, taking advantage of the fact that these variants were derived from the same isolate. Cells preactivated or not with gamma interferon (IFN-γ) were infected with SmOp or SmTr M. fortuitum. We showed that SmOp and SmTr induced different levels of nitric oxide (NO) production by IFN-γ-stimulated Mφ. Indeed, the amount of IFN-γ-induced NO production by J774 cells was 4.8 to 9.0 times higher by SmOp (23.1 to 37.7 μM) compared to SmTr infection (3.9 to 4.8 μM) (P = 0.0332), indicating that virulent SmTr bacilli restricted NO production. In addition, IFN-γ-induced NO production by Mφ was higher when correlated with reduction of only avirulent SmOp bacillus viability. SNAP (S-nitroso-N-acetyl-dl-penicillamine)-induced NO production did not modify SmTr viability, indicating its resistance to nitrogen radicals. Electron microscopy studies were performed to evaluate the capacity of phagosomes to fuse with lysosomes labeled with bovine serum albumin-colloidal gold particles. By 24 h postinfection, 69% more phagosome-containing SmOp variant had fused with lysosomes compared to the SmTr-induced phagosomes. In conclusion, these data indicate that virulent SmTr bacilli may escape host defense by restricting IFN-γ-induced NO production, resisting nitrogen toxic radicals, and limiting phagosome fusion with lysosomes. PMID:12228291

  19. Early Induction of Interleukin-10 Limits Antigen-Specific CD4+ T Cell Expansion, Function, and Secondary Recall Responses during Persistent Phagosomal Infection

    PubMed Central

    Singh, Abinav Kumar

    2014-01-01

    Diverse pathogens have evolved to survive and replicate in the endosomes or phagosomes of the host cells and establish persistent infection. Ehrlichiae are Gram-negative, intracellular bacteria that are transmitted by ticks. Ehrlichiae reside in the endosomes of the host phagocytic or endothelial cells and establish persistent infection in their vertebrate reservoir hosts. CD4+ T cells play a critical role in protection against phagosomal infections. In the present study, we investigated the expansion, maintenance, and functional status of antigen-specific CD4+ T cells during persistent Ehrlichia muris infection in wild-type and interleukin-10 (IL-10)-deficient mice. Our study indicated that early induction of IL-10 led to reduced inflammatory responses and impaired bacterial clearance during persistent Ehrlichia infection. Notably, we demonstrated that the functional production of gamma interferon (IFN-γ) by antigen-specific CD4+ T cells maintained during a persistent phagosomal infection progressively deteriorates. The functional loss of IFN-γ production by antigen-specific CD4+ T cells was reversed in the absence of IL-10. Furthermore, we demonstrated that transient blockade of IL-10 receptor during the T cell priming phase early in infection was sufficient to enhance the magnitude and the functional capacity of antigen-specific effector and memory CD4+ T cells, which translated into an enhanced recall response. Our findings provide new insights into the functional status of antigen-specific CD4+ T cells maintained during persistent phagosomal infection. The study supports the concept that a better understanding of the factors that influence the priming and differentiation of CD4+ T cells may provide a basis to induce a protective immune response against persistent infections. PMID:25024370

  20. Disruption of the phagosomal membrane and egress of Legionella pneumophila into the cytoplasm during the last stages of intracellular infection of macrophages and Acanthamoeba polyphaga.

    PubMed

    Molmeret, Maëlle; Bitar, Dina M; Han, Lihui; Kwaik, Yousef Abu

    2004-07-01

    Although the early stages of intracellular infection by Legionella pneumophila are well established at the ultrastructural level, a detailed ultrastructural analysis of late stages of intracellular replication has never been done. Here we show that the membrane of the L. pneumophila-containing phagosome (LCP) is intact for up to 8 h postinfection of macrophages and Acanthamoeba polyphaga. At 12 h, 71 and 74% of the LCPs are disrupted within macrophages and A. polyphaga, respectively, while the plasma membrane remains intact. At 18 and 24 h postinfection, cytoplasmic elements such as mitochondria, lysosomes, vesicles, and amorphous material are dispersed among the bacteria and these bacteria are considered cytoplasmic. At 18 h, 77% of infected macrophages and 32% of infected A. polyphaga amoebae harbor cytoplasmic bacteria. At 24 h, 99 and 78% of infected macrophages and amoebae, respectively, contain cytoplasmic bacteria. On the basis of lysosomal acid phosphatase staining of infected macrophages and A. polyphaga, the lysosomal enzyme is present among the bacteria when host vesicles are dispersed among bacteria. Our data indicate that bacterial replication proceeds despite physical disruption of the phagosomal membrane. We also show that an lspG mutant that is defective in the type II secretion system and therefore does not secrete the hydrolytic enzymes metalloprotease, p-nitrophenol phosphorylcholine hydrolase, lipase, phospholipase A, and lysophospholipase A is as efficient as the wild-type strain in disruption of the LCP. Therefore, L. pneumophila disrupts the phagosomal membrane and becomes cytoplasmic at the last stages of infection in both macrophages and A. polyphaga. Lysosomal elements, mitochondria, cytoplasmic vesicles, and amorphous material are all dispersed among the bacteria, after phagosomal disruption, within both human macrophages and A. polyphaga. The disruption of the LCP is independent of the hydrolytic enzymes exported by the type II secretion

  1. Inositol Polyphosphate-4-Phosphatase Type I Negatively Regulates Phagocytosis via Dephosphorylation of Phagosomal PtdIns(3,4)P2.

    PubMed

    Nigorikawa, Kiyomi; Hazeki, Kaoru; Sasaki, Junko; Omori, Yumio; Miyake, Mikiko; Morioka, Shin; Guo, Ying; Sasaki, Takehiko; Hazeki, Osamu

    2015-01-01

    Phagocytosis is a highly conserved process whereby phagocytic cells engulf pathogens and apoptotic bodies. The present study focused on the role of inositol polyphosphate-4-phosphatase type I (Inpp4a) in phagocytosis. Raw264.7 cells that express shRNA against Inpp4a (shInpp4a cells) showed significantly increased phagocytic activity. The introduction of shRNA-resistant human Inpp4a abolished this increase. Macrophages from Inpp4a knockout mice showed similar increases in the phagocytic activity. Inpp4a was recruited to the phagosome membrane by a mechanism other than the direct interaction with Rab5. PtdIns(3,4)P2 increased on the phagosome of shInpp4a cells, while PtdIns(3)P significantly decreased. The results indicate that Inpp4a negatively regulates the phagocytic activity of macrophages as a member of the sequential dephosphorylation system that metabolizes phagosomal PtdIns(3,4,5)P3 to PtdIns(3)P.

  2. Inositol Polyphosphate-4-Phosphatase Type I Negatively Regulates Phagocytosis via Dephosphorylation of Phagosomal PtdIns(3,4)P2

    PubMed Central

    Nigorikawa, Kiyomi; Hazeki, Kaoru; Sasaki, Junko; Omori, Yumio; Miyake, Mikiko; Morioka, Shin; Guo, Ying; Sasaki, Takehiko; Hazeki, Osamu

    2015-01-01

    Phagocytosis is a highly conserved process whereby phagocytic cells engulf pathogens and apoptotic bodies. The present study focused on the role of inositol polyphosphate-4-phosphatase type I (Inpp4a) in phagocytosis. Raw264.7 cells that express shRNA against Inpp4a (shInpp4a cells) showed significantly increased phagocytic activity. The introduction of shRNA-resistant human Inpp4a abolished this increase. Macrophages from Inpp4a knockout mice showed similar increases in the phagocytic activity. Inpp4a was recruited to the phagosome membrane by a mechanism other than the direct interaction with Rab5. PtdIns(3,4)P2 increased on the phagosome of shInpp4a cells, while PtdIns(3)P significantly decreased. The results indicate that Inpp4a negatively regulates the phagocytic activity of macrophages as a member of the sequential dephosphorylation system that metabolizes phagosomal PtdIns(3,4,5)P3 to PtdIns(3)P. PMID:26535897

  3. Human oocyte maturation in vitro.

    PubMed

    Coticchio, Giovanni; Dal-Canto, Mariabeatrice; Guglielmo, Maria-Cristina; Mignini-Renzini, Mario; Fadini, Rubens

    2012-01-01

    Oocytes from medium-sized antral follicles have already completed their growth phase and, if released from the follicular environment and cultured in vitro, are able to resume the meiotic process and mature. However, in vitro maturation (IVM) does not entirely support all the nuclear and cytoplasmic changes that occur physiologically as an effect of the ovulatory stimulus. Regardless, oocyte IVM is widely applied for the breeding of agriculturally important species. In assisted reproduction technology, IVM has been proposed as an alternative treatment to circumvent the drawbacks of standard ovarian stimulation regimens. Initially introduced to eliminate the risks of ovarian hyperstimulation syndrome afflicting women presenting with polycystic ovaries, subsequently IVM has been suggested to represent an additional approach suitable also for normovulatory patients. So far, in children born from IVM cycles, no doubts of an increased incidence of congenital abnormalities have been raised. Many more births would be achieved if novel IVM systems, currently dominated by empiricism, could be conceived according to more physiological criteria. Recent findings shedding new light on the control of meiotic progression, the support of cumulus cells to the oocyte cellular reorganization occurring during maturation, and the modulation of the stimulus that promotes oocyte maturation downstream the mid-cycle gonadotropin signal are likely to provide crucial hints for the development of more efficient IVM systems.

  4. Mature Teachers Matter

    ERIC Educational Resources Information Center

    Berl, Patricia Scallan

    2005-01-01

    In this article, the author discusses the consequences of losing mature teachers due to voluntary separation or retirement and the mindset of a mature teacher that is different from younger teachers in a number of ways. Mature teachers are colleagues over 45 years of age possessing significant experience in the field. Future trends in teacher…

  5. Ankyrin-repeat proteins from sponge symbionts modulate amoebal phagocytosis.

    PubMed

    Nguyen, Mary T H D; Liu, Michael; Thomas, Torsten

    2014-03-01

    Bacteria-eukaryote symbiosis occurs in all stages of evolution, from simple amoebae to mammals, and from facultative to obligate associations. Sponges are ancient metazoans that form intimate symbiotic interactions with complex communities of bacteria. The basic nutritional requirements of the sponge are in part satisfied by the phagocytosis of bacterial food particles from the surrounding water. How bacterial symbionts, which are permanently associated with the sponge, survive in the presence of phagocytic cells is largely unknown. Here, we present the discovery of a genomic fragment from an uncultured gamma-proteobacterial sponge symbiont that encodes for four proteins, whose closest known relatives are found in a sponge genome. Through recombinant approaches, we show that these four eukaryotic-like, ankyrin-repeat proteins (ARP) when expressed in Eschericha coli can modulate phagocytosis of amoebal cells and lead to accumulation of bacteria in the phagosome. Mechanistically, two ARPs appear to interfere with phagosome development in a similar way to reduced vacuole acidification, by blocking the fusion of the early phagosome with the lysosome and its digestive enzymes. Our results show that ARP from sponge symbionts can function to interfere with phagocytosis, and we postulate that this might be one mechanism by which symbionts can escape digestion in a sponge host.

  6. Phagosomal pH and glass fiber dissolution in cultured nasal epithelial cells and alveolar macrophages: a preliminary study.

    PubMed Central

    Johnson, N F

    1994-01-01

    The dissolution rate of glass fibers has been shown to be pH sensitive using in vitro lung fluid simulant models. The current study investigated whether there is a difference in phagosomal pH (ppH) between rat alveolar macrophages (AM) and rat nasal epithelial cells (RNEC) and whether such a difference would influence the dissolution of glass fibers. The ppH was measured in cultured AM and RNEC using flow cytometric, fluorescence-emission rationing techniques with fluorescein-labeled, amorphous silica particles. Glass fiber dissolution was determined in AM and RNEC cultured for 3 weeks with fast dissolving glass fibers (GF-A) or slow dissolving ones (GF-B). The mean diameters of GF-A were 2.7 microns and of GF-B, 2.6 microns, the average length of both fibers was approximately 22 to 25 microns. Dissolution was monitored by measuring the length and diameter of intracellular fibers and estimating the volume, assuming a cylindrical morphology. The ppH of AM was 5.2 to 5.8, and the ppH of RNEC was 7.0 to 7.5. The GF-A dissolved more slowly in RNEC than in AM, and no dissolution was evident in either cell type with GF-B. The volume loss with GF-A after a 3-week culture with AM was 66% compared to 45% for cultured RNEC. These results are different from those obtained using in vitro lung fluid-simulant models where dissolution is faster at higher pH. This difference suggests that dissolution rates of glass fibers in AM should not be applied to the dissolution of fibers in epithelial cells. Images Figure 1. a Figure 1. b Figure 2. a Figure 2. b Figure 3. a Figure 3. b PMID:7882965

  7. Myo1 localizes to phagosomes, some of which traffic to the nucleus in a Myo1-dependent manner in Tetrahymena thermophila.

    PubMed

    Hosein, Roland E; Gavin, R H

    2007-12-01

    Myo1 is one of 13 myosins in Tetrahymena thermophila. Initially, twelve of the myosins in Tetrahymena were assigned to Class XX in the myosin superfamily but recently re-assigned to a subclass within Class XIV. In a previous study, we reported that genomic knockout of MYO1 affected phagocytosis and macronuclear amitosis. These two phenotypes have appeared disparate because a possible mechanism linking phagocytosis and amitosis was unknown. In the present study, Myo1 localization was investigated in order to further link machinery for phagocytosis and amitosis. Antibodies directed against the Myo1 motor domain detected an immunospecific polypeptide at 175-180 kDa on immunoblots of wild-type proteins. The 175-180 kDa polypeptide was not detected on immunoblots of proteins from the knockout strain. For immunofluorescence microscopy, cells were allowed to internalize fluorescent beads as markers for phagosomes. In wild-type cells, anti-Myo1 and anti-actin antibodies co-localized to the periphery of phagosomes and the macronucleus. In the MYO1-knockout strain only background fluorescence was observed with anti-Myo1 antibody. Confocal x-z series through macronuclei revealed fluorescent beads within the nucleoplasm. Statistical analysis showed a significant difference between the mean distributions of fluorescent beads in the nucleoplasm of wild-type and MYO1-knockout cells. A fluorescent dye was used to label plasma membrane in living cells. Dye-labeled vacuoles trafficked to the macronucleus. Trafficking of phagosomes to the macronucleus in a myosin-dependent manner is a novel finding and a possible mechanism for targeting myosin and actin to the nucleus.

  8. Phagosomal Acidification Prevents Macrophage Inflammatory Cytokine Production to Malaria, and Dendritic Cells Are the Major Source at the Early Stages of Infection: IMPLICATION FOR MALARIA PROTECTIVE IMMUNITY DEVELOPMENT.

    PubMed

    Wu, Xianzhu; Gowda, Nagaraj M; Gowda, D Channe

    2015-09-18

    Inflammatory cytokines produced at the early stages of malaria infection contribute to shaping protective immunity and pathophysiology. To gain mechanistic insight into these processes, it is important to understand the cellular origin of cytokines because both cytokine input and cytokine-producing cells play key roles. Here, we determined cytokine responses by monocytes, macrophages, and dendritic cells (DCs) to purified Plasmodium falciparum and Plasmodium berghei ANKA, and by spleen macrophages and DCs from Plasmodium yoelii 17NXL-infected and P. berghei ANKA-infected mice. The results demonstrate that monocytes and macrophages do not produce inflammatory cytokines to malaria parasites and that DCs are the primary source early in infection, and DC subsets differentially produce cytokines. Importantly, blocking of phagosomal acidification by inhibiting vacuolar-type H(+)-ATPase enabled macrophages to elicit cytokine responses. Because cytokine responses to malaria parasites are mediated primarily through endosomal Toll-like receptors, our data indicate that the inability of macrophages to produce cytokines is due to the phagosomal acidification that disrupts endosomal ligand-receptor engagement. Macrophages efficiently produced cytokines to LPS upon simultaneously internalizing parasites and to heat-killed Escherichia coli, demonstrating that phagosomal acidification affects endosomal receptor-mediated, but not cell surface receptor-mediated, recognition of Toll-like receptor agonists. Enabling monocytes/macrophages to elicit immune responses to parasites by blocking endosomal acidification can be a novel strategy for the effective development of protective immunity to malaria. The results have important implications for enhancing the efficacy of a whole parasite-based malaria vaccine and for designing strategies for the development of protective immunity to pathogens that induce immune responses primarily through endosomal receptors.

  9. [Adolescent brain maturation].

    PubMed

    Holzer, L; Halfon, O; Thoua, V

    2011-05-01

    Recent progress in neuroscience has yielded major findings regarding brain maturation during adolescence. Unlike the body, which reaches adult size and morphology during this period, the adolescent brain is still maturing. The prefrontal cortex appears to be an important locus of maturational change subserving executive functions that may regulate emotional and motivational issues. The recent expansion of the adolescent period has increased the lag between the onset of emotional and motivational changes activated by puberty and the completion of cognitive development-the maturation of self-regulatory capacities and skills that are continuing to develop long after puberty has occurred. This "disconnect" predicts risk for a broad set of behavioral and emotional problems. Adolescence is a critical period for high-level cognitive functions such as socialization that rely on maturation of the prefrontal cortex. Intervention during the period of adolescent brain development provides opportunities and requires an interdisciplinary approach.

  10. Transcriptomic analysis of the head kidney of Topmouth culter (Culter alburnus) infected with Flavobacterium columnare with an emphasis on phagosome pathway.

    PubMed

    Zhao, Lijuan; Tu, Jiagang; Zhang, Yulei; Wang, Jinfu; Yang, Ling; Wang, Weimin; Wu, Zaohe; Meng, Qinglei; Lin, Li

    2016-10-01

    Flavobacterium columnare (FC) has caused worldwide fish columnaris disease with high mortality and great economic losses in cultured fish, including Topmouth culter (Culter alburnus). However, the knowledge about the host factors involved in FC infection is little known. In this study, the transcriptomic profiles of the head kidney from Topmouth culter with or without FC infection were obtained using HiSeq™ 2500 (Illumina). Totally 79,641 unigenes with high quality were obtained. Among them, 4037 differently expressed genes, including 1217 up-regulated and 2820 down-regulated genes, were identified and enriched using databases of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). The differently expressed genes were mainly associated with pathways such as immune response, carbohydrate metabolism, amino acid metabolism, and lipid metabolism. Since phagocytosis is a central mechanism of innate immune response by host cells to defense against infectious agents, genes related to the phagosome pathway were scrutinized and 9 differently expressed phagosome-related genes were identified including 3 up-regulated and 6 down-regulated genes. Five of them were further validated by quantitative real-time polymerase chain reaction (qRT-PCR). This transcriptomic analysis of host genes in response to FC infection provides data towards understanding the infection mechanisms and will shed a new light on the prevention of columnaris.

  11. Posttesticular sperm maturation, infertility, and hypercholesterolemia

    PubMed Central

    Whitfield, Marjorie; Pollet-Villard, Xavier; Levy, Rachel; Drevet, Joël R; Saez, Fabrice

    2015-01-01

    Cholesterol is a key molecule in the mammalian physiology of especial particular importance for the reproductive system as it is the common precursor for steroid hormone synthesis. Cholesterol is also a recognized modulator of sperm functions, not only at the level of gametogenesis. Cholesterol homeostasis regulation is crucial for posttesticular sperm maturation, and imbalanced cholesterol levels may particularly affect these posttesticular events. Metabolic lipid disorders (dyslipidemia) affect male fertility but are most of the time studied from the angle of endocrine/testicular consequences. This review will focus on the deleterious effects of a particular dyslipidemia, i.e., hypercholesterolemia, on posttesticular maturation of mammalian spermatozoa. PMID:26067871

  12. Toward Teacher Maturity.

    ERIC Educational Resources Information Center

    Pickle, Judy

    1985-01-01

    The essence of teacher maturity can be synthesized into personal, professional, and process domains. Although overlapping, these categories add a multidimensional approach to the search for what is good in teaching and provide a model for professional development. (MT)

  13. Oxidative stress-dependent activation of the eIF2α–ATF4 unfolded protein response branch by skin sensitizer 1-fluoro-2,4-dinitrobenzene modulates dendritic-like cell maturation and inflammatory status in a biphasic manner [corrected].

    PubMed

    Luís, Andreia; Martins, João Demétrio; Silva, Ana; Ferreira, Isabel; Cruz, Maria Teresa; Neves, Bruno Miguel

    2014-12-01

    The pathogenesis of allergic contact dermatitis, the most common manifestation of immunotoxicity in humans, is intimately connected to hapten-induced maturation of dendritic cells (DC). The molecular mechanisms driving this maturational program are not completely known; however, initial danger signals such as the generation of reactive oxygen species (ROS) were shown to play a critical role. Recent evidence linking ROS production, endoplasmic reticulum (ER) stress, and the pathogenesis of several inflammatory diseases led us to analyze, in the present work, the ability of the skin sensitizer 1-fluoro-2,4-dinitrobenzene (DNFB) to evoke ER stress in DC-like THP-1 cells and the concomitant consequences to their immunobiology. We found that DNFB triggers a ROS-dependent activation of the PERK-eIFα-ATF4 unfolded protein response (UPR) branch conferring cytoprotection and modulating the maturation/proinflammatory cell status in a biphasic manner. Early DNFB induction of ATF4 positively modulates autophagy-related genes MAP1LC3B and ATG3 and stabilizes the transcription factor Nrf2, causing a strong induction of the HMOX1-detoxifying gene. Moreover, we observed that in a first phase, DNFB-induced ATF4 upregulates IL8 mRNA levels while blocking CD86, IL1B, IL12B, and CXL10 transcription. Later, following ATF4 decay, HMOX1 and IL8 transcription drastically decrease and CD86, IL1B, and Il12B are upregulated. Overall, our results evidence a connection between sensitizer-induced redox imbalance and the establishment of ER stress in DC-like cells and provide new insights into the role of UPR effectors such as ATF4 to the complex DC maturational program.

  14. Defects in lysosomal maturation facilitate the activation of innate sensors in systemic lupus erythematosus

    PubMed Central

    Monteith, Andrew J.; Kang, SunAh; Scott, Eric; Hillman, Kai; Rajfur, Zenon; Jacobson, Ken; Costello, M. Joseph; Vilen, Barbara J.

    2016-01-01

    Defects in clearing apoptotic debris disrupt tissue and immunological homeostasis, leading to autoimmune and inflammatory diseases. Herein, we report that macrophages from lupus-prone MRL/lpr mice have impaired lysosomal maturation, resulting in heightened ROS production and attenuated lysosomal acidification. Impaired lysosomal maturation diminishes the ability of lysosomes to degrade apoptotic debris contained within IgG–immune complexes (IgG-ICs) and promotes recycling and the accumulation of nuclear self-antigens at the membrane 72 h after internalization. Diminished degradation of IgG-ICs prolongs the intracellular residency of nucleic acids, leading to the activation of Toll-like receptors. It also promotes phagosomal membrane permeabilization, allowing dsDNA and IgG to leak into the cytosol and activate AIM2 and TRIM21. Collectively, these events promote the accumulation of nuclear antigens and activate innate sensors that drive IFNα production and heightened cell death. These data identify a previously unidentified defect in lysosomal maturation that provides a mechanism for the chronic activation of intracellular innate sensors in systemic lupus erythematosus. PMID:27035940

  15. Maturation in Larch 1

    PubMed Central

    Greenwood, Michael S.; Hopper, Catherine A.; Hutchison, Keith W.

    1989-01-01

    The time course of maturation in eastern larch (Larix laricina [Du Roi] K. Koch) was examined by grafting scions from trees of different ages onto 2-year-old root stock and following scion development for several years. Height, diameter, foliar chlorophyll content, and rooting ability of scion-derived cuttings all varied linearly as a function of log10 age. Chlorophyll content (milligrams per gram of dry weight) increased while height, diameter, and ability to root decreased with age (P < 0.01). The tendency toward orthotropic growth and branch formation per centimeter of main stem decreased abruptly between age 1 and 5 years (P < 0.01). Total chlorophyll content of both long and short shoot foliage increased by 30 to 50% with increasing age, but the chlorophyll a/b ratio did not change. Also, juvenile long shoot needles were significantly longer than mature (P < 0.01). Surprisingly, the juvenile scions produced more total strobili over two successive years, but the mature scions produced a significantly higher proportion of male strobili (P < 0.001 year 1; P < 0.02 year 2). The age-related changes in foliar traits were not associated with changes in DNA methylation between juvenile and mature scions. Using HPLC, we found that 20% of foliar DNA cytosine residues were methylated in both scion types. Images Figure 1 PMID:16666785

  16. Mature Students Studying Mathematics.

    ERIC Educational Resources Information Center

    Hirst, Keith

    1999-01-01

    Discusses mature students in the single subject area of mathematics in a single institution and makes comparisons with traditional universities. Reviews some features of the age distribution, entry qualifications, degree-class distribution, non-completion rates and gender distribution. (Author/ASK)

  17. LAMP proteins account for the maturation delay during the establishment of the Coxiella burnetii-containing vacuole.

    PubMed

    Schulze-Luehrmann, Jan; Eckart, Rita A; Ölke, Martha; Saftig, Paul; Liebler-Tenorio, Elisabeth; Lührmann, Anja

    2016-02-01

    The obligate intracellular pathogen Coxiella burnetii replicates in a large phagolysosomal-like vacuole. Currently, both host and bacterial factors required for creating this replicative parasitophorous C. burnetii-containing vacuole (PV) are poorly defined. Here, we assessed the contributions of the most abundant proteins of the lysosomal membrane, LAMP-1 and LAMP-2, to the establishment and maintenance of the PV. Whereas these proteins were not critical for uptake of C. burnetii, they influenced the intracellular replication of C. burnetii. In LAMP-1/2 double-deficient fibroblasts as well as in LAMP-1/2 knock-down cells, C. burnetii establishes a significantly smaller, yet faster maturing vacuole, which harboured more bacteria. The accelerated maturation of PVs in LAMP double-deficient fibroblasts, which was partially or fully reversed by ectopic expression of LAMP-1 or LAMP-2, respectively, was characterized by an increased fusion rate with endosomes, lysosomes and bead-containing phagosomes, but not by different fusion kinetics with autophagy vesicles. These findings establish that LAMP proteins are critical for the maturation delay of PVs. Unexpectedly, neither the creation of the spacious vacuole nor the delay in maturation was found to be prerequisites for the intracellular replication of C. burnetii.

  18. Delayed visual maturation.

    PubMed Central

    Cole, G F; Hungerford, J; Jones, R B

    1984-01-01

    Sixteen blind babies who were considered to be showing the characteristics of delayed visual maturation were studied prospectively. The diagnosis was made on clinical grounds, and the criteria for this are discussed. All of these infants developed visual responses between 4 and 6 months of age and had normal or near normal visual acuities by 1 year of age. Long term follow up, however, has shown neurological abnormalities in some of these children. PMID:6200080

  19. Meristem maturation and inflorescence architecture--lessons from the Solanaceae.

    PubMed

    Park, Soon Ju; Eshed, Yuval; Lippman, Zachary B

    2014-02-01

    Plant apical meristems (AMs) grow continuously by delicately balancing cells leaving at the periphery to form lateral organs with slowly dividing central domain cells that replenish reservoirs of pluripotent cells. This balance can be modified by signals originating from within and outside the meristem, and their integration results in a gradual maturation process that often culminates with the meristem differentiating into a flower. Accompanying this 'meristem maturation' are changes in spacing and size of lateral organs and in rates at which lateral meristems are released from apical dominance. Modulation of distinct meristem maturation parameters through environmental and genetic changes underlies the remarkable diversity of shoot architectures. Here, we discuss recent studies relating the dynamics of meristem maturation with organization of floral branching systems--inflorescences--in the nightshades. From this context, we suggest general principles on how factors coordinating meristem maturation impact shoot organization more broadly.

  20. Vocational Maturity and Self Concepts.

    ERIC Educational Resources Information Center

    Helbing, Hans

    The relationship between separate dimensions of vocational maturity and different self-concept and identity variables were examined. Subjects were Dutch students, age 14-18 years. The vocational maturity dimensions were measured by Dutch adaptations of American vocational maturity scales. Instruments for self-concept and identity measurement were…

  1. Dissociation of motor maturation.

    PubMed

    DiMario, Francis J

    2003-06-01

    We prospectively acquired clinical data regarding the presentation, evaluation, and developmental progress of all patients identified with dissociated motor maturation to define their clinical outcomes. Children (N = 8) referred for evaluation of suspected cerebral palsy because of delayed sitting or walking and identified to have dissociated motor maturation were followed with serial clinical examination. All displayed the characteristic "sitting on air" posture while held in vertical suspension and had otherwise normal developmental assessments. This posture is composed of the hips held in flexion and abduction with the knees extended and feet plantar or dorsiflexed. Three children were initially evaluated at 10 months of age owing to absence of sitting and five other children were evaluated at a mean of 14 months (range 12-19 months) owing to inability to stand. Follow-up evaluations were conducted over a mean of 10.5 months (range 5-34 months). Five children were born prematurely at 34 to 36 weeks gestation. Denver Developmental Screening Test and general and neurologic examinations were normal except to note hypotonia in six children and the "sitting on air" posture in all of the children. Four children have older siblings or parents who "walked late" (after 15 months). On average, the children attained sitting by 8 months (range 7-10 months). One child did not crawl prior to independent walking, two children scooted rather than crawled, and five children crawled at an average of 13.5 months (range 10-16 months). All children cruised by a mean of 18 months (range 16-21.5 months) and attained independent walking by 20.1 months (range 18-25 months). Neuroimaging and serum creatine kinase enzyme testing were normal in two children who were tested. These eight children conform to the syndrome of dissociated motor maturation. The "sitting on air" posture serves as a diagnostic sign and anticipated excellent prognosis, but follow-up is required to ensure a normal

  2. Maturation in Larch 1

    PubMed Central

    Hutchison, Keith W.; Sherman, Christopher D.; Weber, Jill; Smith, Sandra Schiller; Singer, Patricia B.; Greenwood, Michael S.

    1990-01-01

    The effect of maturation on the morphological and photosynthetic characteristics, as well as the expression of two genes involved in photosynthesis in the developing, current year foliage of Eastern larch (Larix laricina [Du Roi]) is described. These effects were observed on foliage during the third growing season after grafting of scions from trees of different ages onto 2 year old rootstock. Specific leaf weight (gram dry weight per square meter), leaf cross-sectional area (per square millimeter), and chlorophyll content (milligram per gram dry weight) all increase with increasing age in long shoot foliage from both indoor- and outdoor-grown trees. Net photosynthesis (NPS) (mole of CO2 per square millimeter per second) increases with age on indoor- but not outdoor-grown trees. NPS also increases with increased chlorophyll content, but outdoor-grown scions of all ages had higher chlorophyll content, and chlorophyll does not appear to be limiting for NPS outdoors. To extend these studies of maturation-related differences in foliar morphology and physiology to the molecular genetic level, sequences were cloned from the cab and rbsS gene families of larch. Both cab and rbcS gene families are expressed in foliage but not in roots, and they are expressed in light-grown seedlings of larch but only at very low levels in dark-grown seedlings (~2% of light-grown seedlings). Steady-state cab mRNA levels are relatively higher (~40%) in newly expanding short shoot foliage from juvenile plants compared to mature plants. Unlike cab, the expression of the rbcS gene family did not seem to vary with age. These data show that the maturation-related changes in morphological and physiological phenotypes are associated with changes in gene expression. No causal relationship has been established, however. Indeed, we conclude that the faster growth of juvenile scions reported previously (MS Greenwood, CA Hopper, KW Hutchison [1989] Plant Physiol 90: 406-412) is not due to increased NPS

  3. The src-family protein-tyrosine kinase p59hck is located on the secretory granules in human neutrophils and translocates towards the phagosome during cell activation.

    PubMed Central

    Möhn, H; Le Cabec, V; Fischer, S; Maridonneau-Parini, I

    1995-01-01

    The src-family protein-tyrosine kinase p59hck is mainly expressed in neutrophils; however, its functional role in these cells is unknown. Several other src-family members are localized on secretory vesicles and have been proposed to regulate intracellular traffic. We have established here the subcellular localization of p59hck in human neutrophils. Immunoblotting of subcellular fractions showed that approx. 60% of the p59hck per cell is localized on the secretory granules; the other 40% is distributed equally between non-granular membranes and the cytosol. Immunofluorescence of neutrophils and HL60 cells suggests that the p59hck-positive granules are azurophil granules. Granular p59hck is highly susceptible to degradation by an azurophil-granule proteinase. Different forms of p59hck occur in the three subcellular compartments: a 61 kDa form is mainly found in the granules, a 59 kDa form is predominant in the non-granular membranes, whereas cytosolic p59hck migrates as a doublet at 63 kDa. During the process of phagocytosis-linked degranulation, induced by serum-opsonized zymosan in neutrophils or HL60 cells, granular p59hck translocates towards the phagosome. The subcellular localization of p59hck suggests that the enzyme could be involved in the regulation of the degranulation process. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:7626033

  4. CFD - Mature Technology?

    NASA Technical Reports Server (NTRS)

    Kwak, Dochan

    2005-01-01

    Over the past 30 years, numerical methods and simulation tools for fluid dynamic problems have advanced as a new discipline, namely, computational fluid dynamics (CFD). Although a wide spectrum of flow regimes are encountered in many areas of science and engineering, simulation of compressible flow has been the major driver for developing computational algorithms and tools. This is probably due to a large demand for predicting the aerodynamic performance characteristics of flight vehicles, such as commercial, military, and space vehicles. As flow analysis is required to be more accurate and computationally efficient for both commercial and mission-oriented applications (such as those encountered in meteorology, aerospace vehicle development, general fluid engineering and biofluid analysis) CFD tools for engineering become increasingly important for predicting safety, performance and cost. This paper presents the author's perspective on the maturity of CFD, especially from an aerospace engineering point of view.

  5. Maturational and Non-Maturational Factors in Heritage Language Acquisition

    ERIC Educational Resources Information Center

    Moon, Ji Hye

    2012-01-01

    This dissertation aims to understand the maturational and non-maturational aspects of early bilingualism and language attrition in heritage speakers who have acquired their L1 incompletely in childhood. The study highlights the influential role of age and input dynamics in early L1 development, where the timing of reduction in L1 input and the…

  6. Localization of mature neprilysin in lipid rafts.

    PubMed

    Sato, Kimihiko; Tanabe, Chiaki; Yonemura, Yoji; Watahiki, Haruhiko; Zhao, Yimeng; Yagishita, Sosuke; Ebina, Maiko; Suo, Satoshi; Futai, Eugene; Murata, Masayuki; Ishiura, Shoichi

    2012-04-01

    Alzheimer's disease (AD) is characterized by senile plaques caused by amyloid-β peptide (Aβ) accumulation. It has been reported that Aβ generation and accumulation occur in membrane microdomains, called lipid rafts, which are enriched in cholesterol and glycosphingolipids. Moreover, the ablation of cholesterol metabolism has been implicated in AD. Neprilysin (NEP), a neutral endopeptidase, is one of the major Aβ-degrading enzymes in the brain. Activation of NEP is a possible therapeutic target. However, it remains unknown whether the activity of NEP is regulated by its association with lipid rafts. Here we show that only the mature form of NEP, which has been glycosylated in the Golgi, exists in lipid rafts, where it is directly associated with phosphatidylserine. Moreover, the localization of NEP in lipid rafts is enhanced by its dimerization, as shown using the NEP E403C homodimerization mutant. However, the protease activities of the mature form of NEP, as assessed by in vitro peptide hydrolysis, did not differ between lipid rafts and nonlipid rafts. We conclude that cholesterol and other lipids regulate the localization of mature NEP to lipid rafts, where the substrate Aβ accumulates but does not modulate the protease activity of NEP.

  7. Career Maturity of Welfare Recipients.

    ERIC Educational Resources Information Center

    Beckman, Carol M.

    To investigate the career maturity of welfare recipients, this thesis examines six independent variables: (1) race; (2) sex; (3) age; (4) level of formal education; (5) general intelligence; and (6) locus of control. Scales taken from the Career Maturity Inventory served as the dependent variables. The sample consisted of 83 welfare recipients who…

  8. Career Education and Career Maturity.

    ERIC Educational Resources Information Center

    Trebilco, Geoffrey R.

    1984-01-01

    Investigated the relationships between career maturity and career curriculum in 38 Melbourne metropolitan secondary schools (N=2280 students) using an Australian adaption of the Career Development Inventory. Results confirmed that schools with career education programs achieved higher gains in student career maturity. (JAC)

  9. 7 CFR 51.3746 - Mature.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Honey Dew and Honey Ball Type Melons Definitions § 51.3746 Mature. Mature means that the melon has reached the stage of maturity which will...

  10. 7 CFR 51.3746 - Mature.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Standards for Grades of Honey Dew and Honey Ball Type Melons Definitions § 51.3746 Mature. Mature means that the melon has reached the stage of maturity which will insure the proper completion of the...

  11. 7 CFR 51.3746 - Mature.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Standards for Grades of Honey Dew and Honey Ball Type Melons Definitions § 51.3746 Mature. Mature means that the melon has reached the stage of maturity which will insure the proper completion of the...

  12. 7 CFR 51.3746 - Mature.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Honey Dew and Honey Ball Type Melons Definitions § 51.3746 Mature. Mature means that the melon has reached the stage of maturity which will...

  13. 7 CFR 51.3746 - Mature.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Standards for Grades of Honey Dew and Honey Ball Type Melons Definitions § 51.3746 Mature. Mature means that the melon has reached the stage of maturity which will insure the proper completion of the...

  14. A proliferation-inducing ligand sustains the proliferation of human naïve (CD27⁻) B cells and mediates their differentiation into long-lived plasma cells in vitro via transmembrane activator and calcium modulator and cyclophilin ligand interactor and B-cell mature antigen.

    PubMed

    Matsuda, Yoshiko; Haneda, Masataka; Kadomatsu, Kenji; Kobayashi, Takaaki

    2015-06-01

    Long-lived plasma cells (PCs) contribute to humoral immunity through an undefined mechanism. Memory B cells, but not human naïve B cells, can be induced to differentiate into long-lived PCs in vitro. Because evidence links a proliferation-inducing ligand (APRIL), a tumor necrosis factor family member, to the ability of bone marrow to mediate long-term PC survival, we reasoned that APRIL influences the proliferation and differentiation of naïve B cells. We describe here the development of a simple cell culture system that allowed us to show that APRIL sustained the proliferation of naïve human B cells and induced them to differentiate into long-lived PCs. Blocking the transmembrane activator and calcium modulator and cyclophilin ligand interactor or B-cell mature antigen shows they were required for the differentiation of naïve B cells into long-lived PCs in vitro. Our in vitro culture system will reveal new insights into the biology of long-lived PCs.

  15. Comparative proteomic exploration of whey proteins in human and bovine colostrum and mature milk using iTRAQ-coupled LC-MS/MS.

    PubMed

    Yang, Mei; Cao, Xueyan; Wu, Rina; Liu, Biao; Ye, Wenhui; Yue, Xiqing; Wu, Junrui

    2017-02-20

    Whey, an essential source of dietary nutrients, is widely used in dairy foods for infants. A total of 584 whey proteins in human and bovine colostrum and mature milk were identified and quantified by the isobaric tag for relative and absolute quantification (iTRAQ) proteomic method. The 424 differentially expressed whey proteins were identified and analyzed according to gene ontology (GO) annotation, Kyoto encyclopedia of genes and genomes (KEGG) pathway, and multivariate statistical analysis. Biological processes principally involved biological regulation and response to stimulus. Major cellular components were extracellular region part and extracellular space. The most prevalent molecular function was protein binding. Twenty immune-related proteins and 13 proteins related to enzyme regulatory activity were differentially expressed in human and bovine milk. Differentially expressed whey proteins participated in many KEGG pathways, including major complement and coagulation cascades and in phagosomes. Whey proteins show obvious differences in expression in human and bovine colostrum and mature milk, with consequences for biological function. The results here increase our understanding of different whey proteomes, which could provide useful information for the development and manufacture of dairy products and nutrient food for infants. The advanced iTRAQ proteomic approach was used to analyze differentially expressed whey proteins in human and bovine colostrum and mature milk.

  16. Ribosome maturation in E. coli.

    PubMed

    Silengo, L; Altruda, F; Dotto, G P; Lacquaniti, F; Perlo, C; Turco, E; Mangiarotti, G

    1977-01-01

    In vivo and in vitro experiments have shown that processing of ribosomal RNA is a late event in ribosome biogenesis. The precursor form of RNA is probably necessary to speed up the assembly of ribomal proteins. Newly formed ribosomal particles which have already entered polyribosomes differ from mature ribosomes not only in their RNA content but also in their susceptibility to unfolding in low Mg concentration and to RNase attack. Final maturation of new ribosomes is probably dependent on their functioning in protein synthesis. Thus only those ribosomes which have proven to be functional may be converted into stable cellular structures.

  17. Space Station Photovoltaic power modules

    NASA Technical Reports Server (NTRS)

    Tatro, Charles A.

    1988-01-01

    Silicon cell Photovoltaic (PV) power modules are key components of the Space Station Electrical Power System (EPS) scheduled to begin deployment in 1994. Four PV power modules, providing 75 KWe of user ac power, form the cornerstone of the EPS; which is comprised of Photovoltaic (PV) power modules, Solar Dynamic (SD) power modules, and the Power Management and Distribution (PMAD) system. The PV modules are located on rotating outboard sections of the Space Station (SS) structure and each module incorporates its own nickel-hydrogen energy storage batteries, its own thermal control system, and some autonomous control features. The PV modules are a cost-effective and technologically mature approach for providing reliable SS electrical power and are a solid base for EPS growth, which is expected to reach 300 KWe by the end of the Space Station's 30-year design lifetime.

  18. Adolescent Maturation in Transitioning Cultures.

    ERIC Educational Resources Information Center

    Mulroy, Kevin; Palacios, Anna; Reid, Robert E.

    This is a theoretical study of adolescent maturation within a cultural context. Personality development and disintegration due to the pressure of a dominant culture on a minority culture is considered. An attempt is made to understand how teachers might assist students to work out their psychological growth by story telling. The need for cultural…

  19. Psychosocial Maturity or Social Desirability?

    ERIC Educational Resources Information Center

    Greenberger, Ellen

    The psychosocial maturity scale (PSM) described in several earlier papers is a self-report questionnaire. It is vulnerable, as are other questionnaires of this type, to respondents' wishes to present themselves in a socially desirable light. In this study, scores on two social desirability scales are examined in relation to PSM. Correlations…

  20. Enticing Mature Females into College.

    ERIC Educational Resources Information Center

    Loseth, Lexie; Moreau, Linda

    Following a review of the literature on mature female students, this paper examines enrollment trends in a selection of colleges in Alberta (Canada) and presents the findings of a survey of returning women students at Red Deer College. The literature review highlights factors related to the personal and professional development of women graduates…

  1. Plastic downregulation of the transcriptional repressor BCL6 during maturation of human dendritic cells

    SciTech Connect

    Pantano, Serafino . E-mail: serafino.pantano@unil.ch; Jarrossay, David; Saccani, Simona; Bosisio, Daniela; Natoli, Gioacchino

    2006-05-01

    Dendritic cell (DC) maturation links peripheral events initiated by the encounter with pathogens to the activation and expansion of antigen-specific T lymphocytes in secondary lymphoid organs. Here, we describe an as yet unrecognized modulator of human DC maturation, the transcriptional repressor BCL6. We found that both myeloid and plasmacytoid DCs constitutively express BCL6, which is rapidly downregulated following maturation triggered by selected stimuli. Both in unstimulated and maturing DCs, control of BCL6 protein levels reflects the convergence of several mechanisms regulating BCL6 stability, mRNA transcription and nuclear export. By regulating the induction of several genes implicated in the immune response, including inflammatory cytokines, chemokines and survival genes, BCL6 may represent a pivotal modulator of the afferent branch of the immune response.

  2. Maturation of Oocytes in Vitro.

    PubMed

    Lonergan, Patrick; Fair, Trudee

    2016-01-01

    Only a fraction of oocytes present in the ovaries at birth are ever ovulated during the lifetime of a female mammal. In vitro maturation (IVM) offers the possibility to exploit what is a largely untapped biological resource. Although IVM is used routinely for the in vitro production of embryos in domestic species, especially cattle, its clinical use in human-assisted reproduction is still evolving. The successful recapitulation in vitro of the events associated with successful oocyte maturation is not always achieved, with the majority of immature oocytes typically failing to develop to the blastocyst stage. Evidence suggests that although culture conditions throughout in vitro embryo production may have a modest influence on the developmental potential of the early embryo, the quality of the oocyte at the start of the process is the key factor determining the proportion of oocytes developing to the blastocyst stage.

  3. Maturation of the adolescent brain

    PubMed Central

    Arain, Mariam; Haque, Maliha; Johal, Lina; Mathur, Puja; Nel, Wynand; Rais, Afsha; Sandhu, Ranbir; Sharma, Sushil

    2013-01-01

    Adolescence is the developmental epoch during which children become adults – intellectually, physically, hormonally, and socially. Adolescence is a tumultuous time, full of changes and transformations. The pubertal transition to adulthood involves both gonadal and behavioral maturation. Magnetic resonance imaging studies have discovered that myelinogenesis, required for proper insulation and efficient neurocybernetics, continues from childhood and the brain’s region-specific neurocircuitry remains structurally and functionally vulnerable to impulsive sex, food, and sleep habits. The maturation of the adolescent brain is also influenced by heredity, environment, and sex hormones (estrogen, progesterone, and testosterone), which play a crucial role in myelination. Furthermore, glutamatergic neurotransmission predominates, whereas gamma-aminobutyric acid neurotransmission remains under construction, and this might be responsible for immature and impulsive behavior and neurobehavioral excitement during adolescent life. The adolescent population is highly vulnerable to driving under the influence of alcohol and social maladjustments due to an immature limbic system and prefrontal cortex. Synaptic plasticity and the release of neurotransmitters may also be influenced by environmental neurotoxins and drugs of abuse including cigarettes, caffeine, and alcohol during adolescence. Adolescents may become involved with offensive crimes, irresponsible behavior, unprotected sex, juvenile courts, or even prison. According to a report by the Centers for Disease Control and Prevention, the major cause of death among the teenage population is due to injury and violence related to sex and substance abuse. Prenatal neglect, cigarette smoking, and alcohol consumption may also significantly impact maturation of the adolescent brain. Pharmacological interventions to regulate adolescent behavior have been attempted with limited success. Since several factors, including age, sex

  4. Maturity model for enterprise interoperability

    NASA Astrophysics Data System (ADS)

    Guédria, Wided; Naudet, Yannick; Chen, David

    2015-01-01

    Historically, progress occurs when entities communicate, share information and together create something that no one individually could do alone. Moving beyond people to machines and systems, interoperability is becoming a key factor of success in all domains. In particular, interoperability has become a challenge for enterprises, to exploit market opportunities, to meet their own objectives of cooperation or simply to survive in a growing competitive world where the networked enterprise is becoming a standard. Within this context, many research works have been conducted over the past few years and enterprise interoperability has become an important area of research, ensuring the competitiveness and growth of European enterprises. Among others, enterprises have to control their interoperability strategy and enhance their ability to interoperate. This is the purpose of the interoperability assessment. Assessing interoperability maturity allows a company to know its strengths and weaknesses in terms of interoperability with its current and potential partners, and to prioritise actions for improvement. The objective of this paper is to define a maturity model for enterprise interoperability that takes into account existing maturity models while extending the coverage of the interoperability domain. The assessment methodology is also presented. Both are demonstrated with a real case study.

  5. 7 CFR 51.2651 - Mature.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades for Sweet Cherries 1 Definitions § 51.2651 Mature. Mature means that the cherries have reached the stage of growth which will insure the...

  6. 7 CFR 51.3058 - Mature.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Florida Avocados Definitions § 51.3058 Mature. Mature means that the avocado has reached a stage of growth which will insure a proper completion of...

  7. 7 CFR 51.2651 - Mature.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades for Sweet Cherries 1 Definitions § 51.2651 Mature. Mature means that the cherries have reached the stage of growth which will insure the...

  8. Career Maturity: The Construct and its Measurement.

    ERIC Educational Resources Information Center

    Savickas, Mark L.

    1984-01-01

    Describes vocational maturity and assists counselors in identifying what the various career maturity instruments measure. Discusses task variable measures, intervening variable measures, response variable measures, and methods of choosing an instrument. (JAC)

  9. Maturation of widely distributed brain function subserves cognitive development.

    PubMed

    Luna, B; Thulborn, K R; Munoz, D P; Merriam, E P; Garver, K E; Minshew, N J; Keshavan, M S; Genovese, C R; Eddy, W F; Sweeney, J A

    2001-05-01

    Cognitive and brain maturational changes continue throughout late childhood and adolescence. During this time, increasing cognitive control over behavior enhances the voluntary suppression of reflexive/impulsive response tendencies. Recently, with the advent of functional MRI, it has become possible to characterize changes in brain activity during cognitive development. In order to investigate the cognitive and brain maturation subserving the ability to voluntarily suppress context-inappropriate behavior, we tested 8-30 year olds in an oculomotor response-suppression task. Behavioral results indicated that adult-like ability to inhibit prepotent responses matured gradually through childhood and adolescence. Functional MRI results indicated that brain activation in frontal, parietal, striatal, and thalamic regions increased progressively from childhood to adulthood. Prefrontal cortex was more active in adolescents than in children or adults; adults demonstrated greater activation in the lateral cerebellum than younger subjects. These results suggest that efficient top-down modulation of reflexive acts may not be fully developed until adulthood and provide evidence that maturation of function across widely distributed brain regions lays the groundwork for enhanced voluntary control of behavior during cognitive development.

  10. Differing roles of pyruvate dehydrogenase kinases during mouse oocyte maturation

    PubMed Central

    Hou, Xiaojing; Zhang, Liang; Han, Longsen; Ge, Juan; Ma, Rujun; Zhang, Xuesen; Moley, Kelle; Schedl, Tim; Wang, Qiang

    2015-01-01

    ABSTRACT Pyruvate dehydrogenase kinases (PDKs) modulate energy homeostasis in multiple tissues and cell types, under various nutrient conditions, through phosphorylation of the α subunit (PDHE1α, also known as PDHA1) of the pyruvate dehydrogenase (PDH) complex. However, the roles of PDKs in meiotic maturation are currently unknown. Here, by undertaking knockdown and overexpression analysis of PDK paralogs (PDK1–PDK4) in mouse oocytes, we established the site-specificity of PDKs towards the phosphorylation of three serine residues (Ser232, Ser293 and Ser300) on PDHE1α. We found that PDK3-mediated phosphorylation of Ser293-PDHE1α results in disruption of meiotic spindle morphology and chromosome alignment and decreased total ATP levels, probably through inhibition of PDH activity. Unexpectedly, we discovered that PDK1 and PDK2 promote meiotic maturation, as their knockdown disturbs the assembly of the meiotic apparatus, without significantly altering ATP content. Moreover, phosphorylation of Ser232-PDHE1α was demonstrated to mediate PDK1 and PDK2 action in meiotic maturation, possibly through a mechanism that is distinct from PDH inactivation. These findings reveal that there are divergent roles of PDKs during oocyte maturation and indicate a new mechanism controlling meiotic structure. PMID:25991547

  11. 7 CFR 51.1158 - Mature.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... § 51.1158 Mature. Mature shall have the same meaning assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February 12, 1995. These orange maturity requirements are contained in the Florida Citrus Code, Chapter...

  12. 7 CFR 51.1823 - Mature.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Mature. Mature shall have the same meaning assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February 12, 1995. These tangerine maturity requirements are contained in the Florida Citrus Code, Chapter...

  13. 7 CFR 51.1158 - Mature.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... § 51.1158 Mature. Mature shall have the same meaning assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February 12, 1995. These orange maturity requirements are contained in the Florida Citrus Code, Chapter...

  14. 7 CFR 51.1823 - Mature.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Mature. Mature shall have the same meaning assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February 12, 1995. These tangerine maturity requirements are contained in the Florida Citrus Code, Chapter...

  15. 7 CFR 51.767 - Mature.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Mature. Mature shall have the same meaning assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February 12, 1995. These grapefruit maturity requirements are contained in the Florida Citrus Code, Chapter...

  16. 7 CFR 51.767 - Mature.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Mature. Mature shall have the same meaning assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February 12, 1995. These grapefruit maturity requirements are contained in the Florida Citrus Code, Chapter...

  17. Career Maturity in High School Age Females.

    ERIC Educational Resources Information Center

    Pedro, Joan Daniels

    1982-01-01

    Examined career maturity in high school females by using a set of general career-maturity and gender-specific, career-related measures, and an alternate career-maturity criterion measure, career-planning involvement. Results indicated significant relationships between achievement orientation and occupational information and knowledge of women's…

  18. 7 CFR 906.11 - Maturity.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Maturity. 906.11 Section 906.11 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... RIO GRANDE VALLEY IN TEXAS Order Regulating Handling Definitions § 906.11 Maturity. Maturity...

  19. [Arrest of maturation in spermatogenesis].

    PubMed

    Francavilla, S; Bellocci, M; Martini, M; Bruno, B; Moscardelli, S; Fabbrini, A; Properzi, G

    1982-07-30

    The ultrastructural aspects of the germinal epithelium of 10 infertile men affected by maturative arrest of spermatogenesis were studied. We noted an increased number of malformed germinal cells. Marginal nuclear vescicles were present in spermatogonia of patients affected by spermatogonial arrest. The few spermatid present in the germinal epithelium of the patients affected by a spermatidic arrest presented changes of the nuclear condensation, the acrosome, and the tail. The Sertoli cells presented an immature aspect of the nucleus and changes of the "mantle". A possible correlation between the Sertoli cells changes and the altered spermatogenesis was proposed.

  20. Phenotype of normal hairline maturation.

    PubMed

    Rassman, William R; Pak, Jae P; Kim, Jino

    2013-08-01

    Hairlines change shape with age, starting at birth. A good head of hair is frequently present some time after ages 3 to 5 years. The look of childhood has its corresponding hairline, and, as the child grows and develops into adulthood, facial morphology migrate changes from a childlike look to a more mature look. This article discusses the dynamics of hairline evolution and the phenotypic variations of the front and side hairlines in men and women. A modeling system is introduced that provides a common language to define the various anatomic points of the full range of hairlines.

  1. Academic Achievement of High School Students in Relation to Their Anxiety, Emotional Maturity and Social Maturity

    ERIC Educational Resources Information Center

    Puar, Surjit Singh

    2013-01-01

    The present study has been designed to investigate the non-cognitive variables like anxiety, emotional maturity and social maturity and their relationship with academic achievement and also to see the locale-wise differences on the basis of their anxiety, emotional maturity and social maturity. The study was conducted over a sample of 400 (200…

  2. The Relationship Between Cognitive Career Maturity and Self-Reported Career Maturity of High School Students.

    ERIC Educational Resources Information Center

    Westbrook, Bert W.; And Others

    1987-01-01

    Investigated relationship between scores on measures of cognitive career maturity and self-reported career maturity in high school sophomores (N=391) and juniors (N=283). Results suggest that there is no relationship between measured career maturity competencies and self-reported career maturity competencies of high school students. (Author/NB)

  3. Sexual maturation of female Saguinus oedipus oedipus

    SciTech Connect

    Tardif, S.D.

    1982-01-01

    This study is an examination of the process of female sexual maturation in the cotton-top tamarin, Saguinus oedipus oedipus, a South-American primate of the family, Callitrichidae. Two types of questions are addressed. The first question is whether the type of social grouping in which a young female lives affects the rate of her sexual maturation. Specifically, is there a difference between the maturation rate of a female housed with a strange adult male and a female housed with her natal group (i.e., her parents and various siblings). Second, the effect of sexual maturation on various social interactions is examined. Specifically are male-female interactions in mated pairs and mother-daughter interactions in natal groups changed by the sexual maturation of the young females. The mother's presence was not related to the daughter's maturation age. However, whether the natal group, as a whole, inhibited maturation, or unrelated males accelerated maturation, or both, remains unknown. Most of the behavioral interactions involving maturing females were unchanged by maturation. There was some indication that certain behaviors were affected by maturation, but only if a strange unrelated male was present.

  4. Neural networks predict tomato maturity stage

    NASA Astrophysics Data System (ADS)

    Hahn, Federico

    1999-03-01

    Almost 40% of the total horticultural produce exported from Mexico the USA is tomato, and quality is fundamental for maintaining the market. Many fruits packed at the green-mature stage do not mature towards a red color as they were harvested before achieving its physiological maturity. Tomato gassed for advancing maturation does not respond on those fruits, and repacking is necessary at terminal markets, causing losses to the producer. Tomato spectral signatures are different on each maturity stage and tomato size was poorly correlated against peak wavelengths. A back-propagation neural network was used to predict tomato maturity using reflectance ratios as inputs. Higher success rates were achieved on tomato maturity stage recognition with neural networks than with discriminant analysis.

  5. Physiological thermoregulation of mature alligators.

    PubMed

    Smith, E N; Standora, E A; Robertson, S L

    1984-01-01

    A 67.1 kg alligator (Alligator mississippiensis), tested in air, heated twice as fast as it cooled. The cooling thermal time constant was 425 min while alive. Warming and cooling thermal time constants were 421 min after death. The thermal time constant was not appropriate in describing warming in air of mature alligators. Surface and subdermal heat flow measurements of the 67.1 kg animal indicate greater blood flow in the skin during warming compared to cooling. Two mature alligators, 49.9 and 103 kg, were heated and cooled in water. Warming time constants were 67 and 110 min respectively. Cooling time constants were 180 and 246 min. Data from this study were combined with previously published thermal time constants for alligators providing regression equations for alligators ranging from 37 g to 103 kg. Regression equations for alligators tested in water are: tau w = 8.81 M050 tau c = 12.6 M0.62. Time constants (tau) are in minutes (w = warming, c = cooling) with all measurements in stirred water; mass, M, is in kg. Thermal conductance and metabolism data are combined to provide an estimate of the amount the body temperature of theoretical alligators ranging from 50 g to 1000 kg would be elevated by metabolism. A body temperature of 34.2 degrees C is predicted for a 1000 kg theoretical alligator in 30 degrees C water.

  6. Membrane remodeling during reticulocyte maturation

    PubMed Central

    Liu, Jing; Guo, Xinhua; Mohandas, Narla; Chasis, Joel A.

    2010-01-01

    The transition of reticulocytes into erythrocytes is accompanied by extensive changes in the structure and properties of the plasma membrane. These changes include an increase in shear resistance, loss of surface area, and acquisition of a biconcave shape. The processes by which these changes are effected have remained largely undefined. Here we examine how the expression of 30 distinct membrane proteins and their interactions change during murine reticulocyte maturation. We show that tubulin and cytosolic actin are lost, whereas the membrane content of myosin, tropomyosin, intercellular adhesion molecule-4, glucose transporter-4, Na-K-ATPase, sodium/hydrogen exchanger 1, glycophorin A, CD47, Duffy, and Kell is reduced. The degradation of tubulin and actin is, at least in part, through the ubiquitin-proteasome degradation pathway. In regard to the protein-protein interactions, the formation of membrane-associated spectrin tetramers from dimers is unperturbed, whereas the interactions responsible for the formation of the membrane-skeletal junctions are weaker in reticulocytes, as is the attachment of transmembrane proteins to these structures. This weakness, in part, results from the elevated phosphorylation of 4.1R in reticulocytes, which leads to a decrease in shear resistance by reducing its interaction with spectrin and actin. These observations begin to unravel the mechanistic basis of crucial changes accompanying reticulocyte maturation. PMID:20038785

  7. Sexual maturation in kokanee Oncorhynchus nerka

    USGS Publications Warehouse

    Patterson, S.D.; Scarnecchia, D.L.; Congleton, J.L.

    2008-01-01

    We used observational and experimental approaches to obtain information on factors affecting the timing of maturation of kokanee Oncorhynchus nerka, a semelparous, landlocked salmon. Gonadal staging criteria were developed and applied to three kokanee populations in Idaho lakes and reservoirs. Testes were classified into three stages: immature (stage one, S1), maturing (S2), and mature (S3). Ovaries were classified into eight stages: immature (S1-S3), transitional (stage S4), maturing (S5-S7), and mature (S8). Males entered the maturing stage (S2) in February through April of the spawning year. Females entered maturing stage (S5) as early as July of the year before the spawning year, and as late as March of the spawning year. Three hatchery experiments demonstrated that attainment of a larger body size 10 to 16 months before spawning increased the likelihood of initiation of maturation in both sexes. No gonads in a state of regression were observed. A gonadosomatic index above 0.1 by early July was a good indicator of a maturing male, and a gonadosomatic index above 1.0 by early July was a good indicator of a maturing female. Instantaneous growth rates were not good predictors of maturation, but attaining a size threshold of 18 to 19 cm in the fall was a good predictor of maturation the following year. This improved knowledge of kokanee maturation will permit more effectively management of the species for age, growth and size at maturity as well as for contributions to fisheries. ?? 2008 by the Northwest Scientific Association. All rights reserved.

  8. Modulation techniques

    NASA Technical Reports Server (NTRS)

    Schilling, D. L.

    1982-01-01

    Bandwidth efficient digital modulation techniques, proposed for use on and/or applied to satellite channels, are reviewed. In a survey of recent works on digital modulation techniques, the performance of several schemes operating in various environments are compared. Topics covered include: (1) quadrature phase shift keying; (2) offset - QPSK and MSK; (3) combined modulation and coding; and (4) spectrally efficient modulation techniques.

  9. Maturation of the MOUTh Intervention

    PubMed Central

    Jablonski-Jaudon, Rita A.; Kolanowski, Ann M.; Winstead, Vicki; Jones-Townsend, Corteza; Azuero, Andres

    2016-01-01

    The purpose of the current article is to describe a personalized practice originally conceived as a way to prevent and minimize care-resistant behavior to provide mouth care to older adult with dementia. The original intervention, Managing Oral Hygiene Using Threat Reduction Strategies (MOUTh), matured during the clinical trial study into a relationship-centered intervention with emphasis on developing strategies that support residents behavioral health and staff involved in care. Relationships that were initially pragmatic (i.e., focused on the task of completing mouth care) developed into more personal and responsive relationships that involved deeper engagement between mouth care providers and nursing home (NH) residents. Mouth care was accomplished and completed in a manner enjoyable to NH residents and mouth care providers. The MOUTh intervention may also concurrently affirm the dignity and personhood of the care recipient because of its emphasis on connecting with older adults. PMID:26934969

  10. Optimizing IV and V for Mature Organizations

    NASA Technical Reports Server (NTRS)

    Fuhman, Christopher

    2003-01-01

    NASA is intending for its future software development agencies to have at least a Level 3 rating in the Carnegie Mellon University Capability Maturity Model (CMM). The CMM has built-in Verification and Validation (V&V) processes that support higher software quality. Independent Verification and Validation (IV&V) of software developed by mature agencies can be therefore more effective than for software developed by less mature organizations. How is Independent V&V different with respect to the maturity of an organization? Knowing a priori the maturity of an organization's processes, how can IV&V planners better identify areas of need choose IV&V activities, etc? The objective of this research is to provide a complementary set of guidelines and criteria to assist the planning of IV&V activities on a project using a priori knowledge of the measurable levels of maturity of the organization developing the software.

  11. Skeletal maturation determined by cervical vertebrae development.

    PubMed

    San Román, Paloma; Palma, Juan Carlos; Oteo, M Dolores; Nevado, Esther

    2002-06-01

    The aim of this study was to determine the validity of cervical vertebrae radiographic assessment to predict skeletal maturation. Left hand-wrist and lateral cephalometric radiographs of 958 Spanish children from 5 to 18 years of age were measured. On the left hand-wrist radiographs the classification of Grave and Brown was used to assess skeletal maturation. Cervical vertebrae maturation was evaluated with lateral cephalometric radiographs using the stages described by Lamparski and by Hassel and Farman. A new method to evaluate the cervical maturation by studying the changes in the concavity of the lower border, height, and shape of the vertebral body was created. Correlation coefficients were calculated to establish the relationship between skeletal maturation values obtained by the three classifications of vertebral and skeletal maturation measured at the wrist. All correlation values obtained were statistically significant (P < 0.001). The results suggest that this new method to determine skeletal maturation is very reliable. A simple method based on morphological characteristics of the cervical vertebral bodies to evaluate the maturation stage has been designed. In the population investigated, this method is as accurate as the Hassel and Farman classification and superior to the Lamparski classification. The morphological vertebral parameter best able to estimate the maturation is the concavity of the lower border of the body.

  12. Advanced Stirling Convertor (ASC) Technology Maturation

    NASA Technical Reports Server (NTRS)

    Wong, Wayne A.; Wilson, Scott; Collins, Josh; Wilson, Kyle

    2015-01-01

    The Advanced Stirling Convertor (ASC) development effort was initiated by NASA Glenn Research Center (GRC) with contractor Sunpower Inc. to develop high efficiency thermal-to-electric power conversion technology for NASA Radioisotope Power Systems. Early successful performance demonstrations led to the expansion of the project as well as adoption of the technology by the Department of Energy (DOE) and system integration contractor Lockheed Martin Space Systems Company as part of the Advanced Stirling Radioisotope Generator (ASRG) flight project. The ASRG integrates a pair of ASCs to convert the heat from a pair of General Purpose Heat Source (GPHS) modules into electrical power. The expanded NASA ASC effort included development of several generations of ASC prototypes or Engineering Units to help prepare the ASC technology and Sunpower for flight implementation. Sunpower later had two parallel contracts allowing the last of the NASA Engineering Units called ASC-E3 to serve as pathfinders for the ASC-F flight convertors being built for DOE. The ASC-E3 convertors utilized the ASC-F flight specifications and were built using the ASC-F design and process documentation. Shortly after the first ASC-F Pair achieved initial operation, due to budget constraints, the DOE ASRG flight development contract was terminated. NASA continues to invest in the development of Stirling RPS technology including continued production of the ASC-E3 convertors, seven of which have been delivered with one additional unit in production. Starting in FY2015, Stirling Convertor Technology Maturation has been reorganized as an element of the RPS Stirling Cycle Technology Development (SCTD) Project and long-term plans for continued Stirling technology advancement are in reformulation. This paper provides a status on the ASC project, an overview of advancements made in the design and production of the ASC at Sunpower, and a summary of acceptance tests, reliability tests, and tactical tests at NASA

  13. Advanced Stirling Convertor (ASC) Technology Maturation

    NASA Technical Reports Server (NTRS)

    Wong, Wayne A.; Wilson, Scott; Collins, Josh; Wilson, Kyle

    2016-01-01

    The Advanced Stirling Convertor (ASC) development effort was initiated by NASA Glenn Research Center with contractor Sunpower, Inc., to develop high-efficiency thermal-to-electric power conversion technology for NASA Radioisotope Power Systems (RPSs). Early successful performance demonstrations led to the expansion of the project as well as adoption of the technology by the Department of Energy (DOE) and system integration contractor Lockheed Martin Space Systems Company as part of the Advanced Stirling Radioisotope Generator (ASRG) flight project. The ASRG integrates a pair of ASCs to convert the heat from a pair of General Purpose Heat Source (GPHS) modules into electrical power. The expanded NASA ASC effort included development of several generations of ASC prototypes or engineering units to help prepare the ASC technology and Sunpower for flight implementation. Sunpower later had two parallel contracts allowing the last of the NASA engineering units called ASC-E3 to serve as pathfinders for the ASC-F flight convertors being built for DOE. The ASC-E3 convertors utilized the ASC-F flight specifications and were built using the ASC-F design and process documentation. Shortly after the first ASC-F pair achieved initial operation, due to budget constraints, the DOE ASRG flight development contract was terminated. NASA continues to invest in the development of Stirling RPS technology including continued production of the ASC-E3 convertors, seven of which have been delivered with one additional unit in production. Starting in fiscal year 2015, Stirling Convertor Technology Maturation has been reorganized as an element of the RPS Stirling Cycle Technology Development (SCTD) Project and long-term plans for continued Stirling technology advancement are in reformulation. This paper provides a status on the ASC project, an overview of advancements made in the design and production of the ASC at Sunpower, and a summary of acceptance tests, reliability tests, and tactical

  14. Structural dynamics control the MicroRNA maturation pathway

    PubMed Central

    Dallaire, Paul; Tan, Huiping; Szulwach, Keith; Ma, Christopher; Jin, Peng; Major, François

    2016-01-01

    MicroRNAs (miRNAs) are crucial gene expression regulators and first-order suspects in the development and progression of many diseases. Comparative analysis of cancer cell expression data highlights many deregulated miRNAs. Low expression of miR-125a was related to poor breast cancer prognosis. Interestingly, a single nucleotide polymorphism (SNP) in miR-125a was located within a minor allele expressed by breast cancer patients. The SNP is not predicted to affect the ground state structure of the primary transcript or precursor, but neither the precursor nor mature product is detected by RT-qPCR. How this SNP modulates the maturation of miR-125a is poorly understood. Here, building upon a model of RNA dynamics derived from nuclear magnetic resonance studies, we developed a quantitative model enabling the visualization and comparison of networks of transient structures. We observed a high correlation between the distances between networks of variants with that of their respective wild types and their relative degrees of maturation to the latter, suggesting an important role of transient structures in miRNA homeostasis. We classified the human miRNAs according to pairwise distances between their networks of transient structures. PMID:27651454

  15. Leishmania major Promastigotes Evade LC3-Associated Phagocytosis through the Action of GP63

    PubMed Central

    Matte, Christine; Casgrain, Pierre-André; Séguin, Olivier; Moradin, Neda; Hong, Wan Jin; Descoteaux, Albert

    2016-01-01

    The protozoan Leishmania parasitizes macrophages and evades the microbicidal consequences of phagocytosis through the inhibition of phagolysosome biogenesis. In this study, we investigated the impact of this parasite on LC3-associated phagocytosis, a non-canonical autophagic process that enhances phagosome maturation and functions. We show that whereas internalization of L. major promastigotes by macrophages promoted LC3 lipidation, recruitment of LC3 to phagosomes was inhibited through the action of the parasite surface metalloprotease GP63. Reactive oxygen species generated by the NOX2 NADPH oxidase are necessary for LC3-associated phagocytosis. We found that L. major promastigotes prevented, in a GP63-dependent manner, the recruitment of NOX2 to phagosomes through a mechanism that does not involve NOX2 cleavage. Moreover, we found that the SNARE protein VAMP8, which regulates phagosomal assembly of the NADPH oxidase NOX2, was down-modulated by GP63. In the absence of VAMP8, recruitment of LC3 to phagosomes containing GP63-deficient parasites was inhibited, indicating that VAMP8 is involved in the phagosomal recruitment of LC3. These findings reveal a role for VAMP8 in LC3-associated phagocytosis and highlight a novel mechanism exploited by L. major promastigotes to interfere with the host antimicrobial machinery. PMID:27280768

  16. Smart Grid Interoperability Maturity Model

    SciTech Connect

    Widergren, Steven E.; Levinson, Alex; Mater, J.; Drummond, R.

    2010-04-28

    The integration of automation associated with electricity resources (including transmission and distribution automation and demand-side resources operated by end-users) is key to supporting greater efficiencies and incorporating variable renewable resources and electric vehicles into the power system. The integration problems faced by this community are analogous to those faced in the health industry, emergency services, and other complex communities with many stakeholders. To highlight this issue and encourage communication and the development of a smart grid interoperability community, the GridWise Architecture Council (GWAC) created an Interoperability Context-Setting Framework. This "conceptual model" has been helpful to explain the importance of organizational alignment in addition to technical and informational interface specifications for "smart grid" devices and systems. As a next step to building a community sensitive to interoperability, the GWAC is investigating an interoperability maturity model (IMM) based on work done by others to address similar circumstances. The objective is to create a tool or set of tools that encourages a culture of interoperability in this emerging community. The tools would measure status and progress, analyze gaps, and prioritize efforts to improve the situation.

  17. An siRNA-based method for efficient silencing of gene expression in mature brown adipocytes

    PubMed Central

    Isidor, Marie S.; Winther, Sally; Basse, Astrid L.; Petersen, M. Christine H.; Cannon, Barbara; Nedergaard, Jan; Hansen, Jacob B.

    2016-01-01

    ABSTRACT Brown adipose tissue is a promising therapeutic target for opposing obesity, glucose intolerance and insulin resistance. The ability to modulate gene expression in mature brown adipocytes is important to understand brown adipocyte function and delineate novel regulatory mechanisms of non-shivering thermogenesis. The aim of this study was to optimize a lipofection-based small interfering RNA (siRNA) transfection protocol for efficient silencing of gene expression in mature brown adipocytes. We determined that a critical parameter was to deliver the siRNA to mature adipocytes by reverse transfection, i.e. transfection of non-adherent cells. Using this protocol, we effectively knocked down both high- and low-abundance transcripts in a model of mature brown adipocytes (WT-1) as well as in primary mature mouse brown adipocytes. A functional consequence of the knockdown was confirmed by an attenuated increase in uncoupled respiration (thermogenesis) in response to β-adrenergic stimulation of mature WT-1 brown adipocytes transfected with uncoupling protein 1 siRNA. Efficient gene silencing was also obtained in various mouse and human white adipocyte models (3T3-L1, primary mouse white adipocytes, hMADS) with the ability to undergo “browning.” In summary, we report an easy and versatile reverse siRNA transfection protocol to achieve specific silencing of gene expression in various models of mature brown and browning-competent white adipocytes, including primary cells. PMID:27386153

  18. Effect of maturity and hybrid on ruminal and intestinal digestion of corn silage in dry cows.

    PubMed

    Peyrat, J; Baumont, R; Le Morvan, A; Nozière, P

    2016-01-01

    The aim of this study was to evaluate the effect of stage of maturity at harvest on extent of starch, neutral detergent fiber (NDF), and protein digestion, and rumen fermentation in dry cows fed whole-plant corn silage from different hybrids. Four nonlactating Holstein cows cannulated at the rumen and proximal duodenum were fed 4 corn silages differing in hybrid (flint vs. flint-dent) and maturity stage (early vs. late) in a 4 × 4 Latin square design. From early to late maturity, starch content increased (from 234.5 to 348.5 g/kg), whereas total-tract (99.7 to 94.5%) and ruminal starch digestibility (91.3 to 86.5%) decreased significantly. The decrease in ruminal starch digestibility with increasing maturity was similar between hybrids. No effects were found of maturity, hybrid, or maturity × hybrid interaction on total-tract NDF digestibility, ruminal NDF digestibility, true digestibility of N and organic matter in the rumen, or microbial synthesis. Harvesting at later maturity led to increased ruminal ammonia, total volatile fatty acid concentrations, and acetate/propionate ratio but not pH. This study concludes that delaying date of harvest modifies the proportions of digestible starch and NDF supplied to cattle. Adjusting date of corn harvest to modulate amount of rumen-digested starch could be used as a strategy to control nutrient delivery to ruminants.

  19. Pet-1 Switches Transcriptional Targets Postnatally to Regulate Maturation of Serotonin Neuron Excitability

    PubMed Central

    Wyler, Steven C.; Spencer, W. Clay; Green, Noah H.; Rood, Benjamin D.; Crawford, LaTasha; Craige, Caryne; Gresch, Paul; McMahon, Douglas G.; Beck, Sheryl G.

    2016-01-01

    Newborn neurons enter an extended maturation stage, during which they acquire excitability characteristics crucial for development of presynaptic and postsynaptic connectivity. In contrast to earlier specification programs, little is known about the regulatory mechanisms that control neuronal maturation. The Pet-1 ETS (E26 transformation-specific) factor is continuously expressed in serotonin (5-HT) neurons and initially acts in postmitotic precursors to control acquisition of 5-HT transmitter identity. Using a combination of RNA sequencing, electrophysiology, and conditional targeting approaches, we determined gene expression patterns in maturing flow-sorted 5-HT neurons and the temporal requirements for Pet-1 in shaping these patterns for functional maturation of mouse 5-HT neurons. We report a profound disruption of postmitotic expression trajectories in Pet-1−/− neurons, which prevented postnatal maturation of 5-HT neuron passive and active intrinsic membrane properties, G-protein signaling, and synaptic responses to glutamatergic, lysophosphatidic, and adrenergic agonists. Unexpectedly, conditional targeting revealed a postnatal stage-specific switch in Pet-1 targets from 5-HT synthesis genes to transmitter receptor genes required for afferent modulation of 5-HT neuron excitability. 5-HT1a autoreceptor expression depended transiently on Pet-1, thus revealing an early postnatal sensitive period for control of 5-HT excitability genes. Chromatin immunoprecipitation followed by sequencing revealed that Pet-1 regulates 5-HT neuron maturation through direct gene activation and repression. Moreover, Pet-1 directly regulates the 5-HT neuron maturation factor Engrailed 1, which suggests Pet-1 orchestrates maturation through secondary postmitotic regulatory factors. The early postnatal switch in Pet-1 targets uncovers a distinct neonatal stage-specific function for Pet-1, during which it promotes maturation of 5-HT neuron excitability. SIGNIFICANCE STATEMENT The

  20. Evolutionary and Developmental Modules

    PubMed Central

    Lacquaniti, Francesco; Ivanenko, Yuri P.; d’Avella, Andrea; Zelik, Karl E.; Zago, Myrka

    2013-01-01

    The identification of biological modules at the systems level often follows top-down decomposition of a task goal, or bottom-up decomposition of multidimensional data arrays into basic elements or patterns representing shared features. These approaches traditionally have been applied to mature, fully developed systems. Here we review some results from two other perspectives on modularity, namely the developmental and evolutionary perspective. There is growing evidence that modular units of development were highly preserved and recombined during evolution. We first consider a few examples of modules well identifiable from morphology. Next we consider the more difficult issue of identifying functional developmental modules. We dwell especially on modular control of locomotion to argue that the building blocks used to construct different locomotor behaviors are similar across several animal species, presumably related to ancestral neural networks of command. A recurrent theme from comparative studies is that the developmental addition of new premotor modules underlies the postnatal acquisition and refinement of several different motor behaviors in vertebrates. PMID:23730285

  1. 7 CFR 51.312 - Mature.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Definitions § 51.312 Mature. “Mature” means that the apples have reached the stage of development which will insure the proper completion of the ripening process. Before a mature apple becomes overripe it will show varying degrees of...

  2. 7 CFR 51.312 - Mature.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Definitions § 51.312 Mature. “Mature” means that the apples have reached the stage of development which will insure the proper completion of the ripening process. Before a mature apple becomes overripe it will show varying degrees of...

  3. The Mature Woman and the Community College

    ERIC Educational Resources Information Center

    Elliot, Jeffrey M.; Mantz, Concetta M.

    1976-01-01

    The factors and motivations contributing to the presence of increasing numbers of mature women in college are examined, and seven proposals are offered, representing an attempt to develop a total community college program which will meet the needs of mature women students. (NHM)

  4. Quantifying Semantic Linguistic Maturity in Children

    ERIC Educational Resources Information Center

    Hansson, Kristina; Bååth, Rasmus; Löhndorf, Simone; Sahlén, Birgitta; Sikström, Sverker

    2016-01-01

    We propose a method to quantify "semantic linguistic maturity" (SELMA) based on a high dimensional semantic representation of words created from the co-occurrence of words in a large text corpus. The method was applied to oral narratives from 108 children aged 4;0-12;10. By comparing the SELMA measure with maturity ratings made by human…

  5. 7 CFR 29.6026 - Maturity.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Maturity. 29.6026 Section 29.6026 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Standards Definitions § 29.6026 Maturity. The degree of ripeness. (See chart.)...

  6. New definitions for cotton fiber maturity ratio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton fiber maturity affects fiber physical, mechanical, and chemical properties, as well as the processability and qualities of yarn and fabrics. New definitions of cotton fiber maturity ratio are introduced. The influences of sampling, sample preparation, measurement method, and correlations am...

  7. Thinned Mature Deciduous Forest Silvopastures for Appalachia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Little information is available on effective management and utilization of silvopastures developed from the ubiquitous mature woodlots which comprise 40-50% of small Appalachian farm acreage. We thinned a white oak dominated mature second growth forested area establishing two 0.5 ha, eight-paddock,...

  8. Canopy temperature and maturity in cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Heat units are a widely used indicator of maturity in cotton. It is generally assumed that it takes approximately 2200°F (1222°C) heat units for a cotton plant on the South High Plains of Texas to mature. This value is based on a typical planting date of May 15 with ample irrigation. As water for c...

  9. Motivation and Maturity Patterns in Marital Success.

    ERIC Educational Resources Information Center

    McClelland, David C.; And Others

    1978-01-01

    Married couples rated their marital satisfaction and played interpersonal competitive games which revealed the success with which they interacted. Younger husbands who scored more maturely on the Stewart measure of psychosocial maturity belonged to more successful marriages, as did college-educated wives who showed less immaturity and more phallic…

  10. 24 CFR 200.82 - Maturity.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... GENERAL INTRODUCTION TO FHA PROGRAMS Requirements for Application, Commitment, and Endorsement Generally... Requirements for Existing Projects Mortgage Provisions § 200.82 Maturity. The mortgage shall have a maturity... included under the applicable section of the Act. (2) Thirty-five years for existing projects, except...

  11. 24 CFR 200.82 - Maturity.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... GENERAL INTRODUCTION TO FHA PROGRAMS Requirements for Application, Commitment, and Endorsement Generally... Requirements for Existing Projects Mortgage Provisions § 200.82 Maturity. The mortgage shall have a maturity... included under the applicable section of the Act. (2) Thirty-five years for existing projects, except...

  12. Toward the Measurement of Psychosocial Maturity.

    ERIC Educational Resources Information Center

    Greenberger, Ellen; And Others

    The concept of psychosocial maturity is reviewed in preparation for the exploration of the feasibility of constructing a scale that measures maturity. Investigation produced a preliminary 54-item scale with high reliability and moderate validity, which is appended. A factor analysis of the scale supports the a priori structure by the theoretical…

  13. The FMI: Dimensions of Follower Maturity

    ERIC Educational Resources Information Center

    Moore, Loren I.

    1976-01-01

    The Follower Maturity Index (FMI) is an instrument derived from leadership theory and based on observations of verbal and nonverbal behavior of followers in task groups. Dimensions of follower maturity--achievement, responsibility, experience, activity, dependence, variety, interests, perspective, position, and awareness--are discussed. For…

  14. 7 CFR 1421.101 - Maturity dates.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS GRAINS AND SIMILARLY HANDLED COMMODITIES-MARKETING ASSISTANCE LOANS AND LOAN DEFICIENCY PAYMENTS FOR 2008 THROUGH 2012 Marketing Assistance Loans § 1421.101 Maturity dates. (a)(1) All marketing assistance loans shall mature on demand by CCC and no later than...

  15. 7 CFR 1421.101 - Maturity dates.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS GRAINS AND SIMILARLY HANDLED COMMODITIES-MARKETING ASSISTANCE LOANS AND LOAN DEFICIENCY PAYMENTS FOR 2008 THROUGH 2012 Marketing Assistance Loans § 1421.101 Maturity dates. (a)(1) All marketing assistance loans shall mature on demand by CCC and no later than...

  16. 7 CFR 1421.101 - Maturity dates.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS GRAINS AND SIMILARLY HANDLED COMMODITIES-MARKETING ASSISTANCE LOANS AND LOAN DEFICIENCY PAYMENTS FOR 2008 THROUGH 2012 Marketing Assistance Loans § 1421.101 Maturity dates. (a)(1) All marketing assistance loans shall mature on demand by CCC and no later than...

  17. 7 CFR 1421.101 - Maturity dates.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS GRAINS AND SIMILARLY HANDLED COMMODITIES-MARKETING ASSISTANCE LOANS AND LOAN DEFICIENCY PAYMENTS FOR 2008 THROUGH 2012 Marketing Assistance Loans § 1421.101 Maturity dates. (a)(1) All marketing assistance loans shall mature on demand by CCC and no later than...

  18. 24 CFR 201.11 - Loan maturities.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Loan maturities. 201.11 Section 201... DEVELOPMENT MORTGAGE AND LOAN INSURANCE PROGRAMS UNDER NATIONAL HOUSING ACT AND OTHER AUTHORITIES TITLE I PROPERTY IMPROVEMENT AND MANUFACTURED HOME LOANS Loan and Note Provisions § 201.11 Loan maturities....

  19. 24 CFR 201.11 - Loan maturities.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 2 2013-04-01 2013-04-01 false Loan maturities. 201.11 Section 201... DEVELOPMENT MORTGAGE AND LOAN INSURANCE PROGRAMS UNDER NATIONAL HOUSING ACT AND OTHER AUTHORITIES TITLE I PROPERTY IMPROVEMENT AND MANUFACTURED HOME LOANS Loan and Note Provisions § 201.11 Loan maturities....

  20. 24 CFR 201.11 - Loan maturities.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 2 2012-04-01 2012-04-01 false Loan maturities. 201.11 Section 201... DEVELOPMENT MORTGAGE AND LOAN INSURANCE PROGRAMS UNDER NATIONAL HOUSING ACT AND OTHER AUTHORITIES TITLE I PROPERTY IMPROVEMENT AND MANUFACTURED HOME LOANS Loan and Note Provisions § 201.11 Loan maturities....

  1. 24 CFR 201.11 - Loan maturities.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 2 2014-04-01 2014-04-01 false Loan maturities. 201.11 Section 201... DEVELOPMENT MORTGAGE AND LOAN INSURANCE PROGRAMS UNDER NATIONAL HOUSING ACT AND OTHER AUTHORITIES TITLE I PROPERTY IMPROVEMENT AND MANUFACTURED HOME LOANS Loan and Note Provisions § 201.11 Loan maturities....

  2. 7 CFR 51.1238 - Mature.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... Standards for Cleaned Virginia Type Peanuts in the Shell Definitions § 51.1238 Mature. Mature means that...

  3. Probiotics can induce follicle maturational competence: the Danio rerio case.

    PubMed

    Gioacchini, Giorgia; Giorgini, Elisabetta; Merrifield, Daniel L; Hardiman, Gary; Borini, Andrea; Vaccari, Lisa; Carnevali, Oliana

    2012-03-01

    In the present study, the effects of the probiotic Lactobacillus rhamnosus IMC 501 on the acquisition of oocyte maturational competence was examined in zebrafish (Danio rerio). L. rhamnosus administration induced the responsiveness of incompetent follicles (stage IIIa) to 17,20-dihydroxy-4-pregnen-3-one and their in vitro maturation. Acquisition of competence by the stage IIIa follicles was further validated by changes of lhr, mprb, inhbaa (activin betaA1), tgfb1, and gdf9 gene expression, which have recently emerged as key regulators of oocyte acquisition of maturational competence, and pou5f1 gene expression, which in other models has been shown to govern the establishment of developmental competence of oocytes. In addition, a DNA microarray experiment was conducted using the same follicles, and with relative gene ontology (GO) data analysis, the molecular effects of probiotic administration emerged. Molecular analysis using PCR-DGGE (denaturing gradient gel electrophoresis) approach, providing information about only the most abundant bacterial members of the microbial community, revealed that the probiotic was able to populate the gastrointestinal tract and modulate the microbial communities, causing a clear shift in them and specifically enhancing the presence of the lactic acid bacteria Streptococcus thermophilus. At the same time, PCR-DGGE analysis revealed that the probiotic was not directly associated with the ovaries. Finally, the effects of probiotic treatment on zebrafish follicle development were also analyzed by FPA (focal plane array) Fourier transform-infrared (FT-IR) imaging, a technique that provides the overall biochemical composition of samples. Changes were found above all in stage IIIa follicles from probiotic-exposed females; the modifications, observed in protein secondary structures as well as in hydration and in bands related to phosphate moieties, allowed us to hypothesize that probiotics act at this follicle stage, affecting the

  4. Module Configuration

    DOEpatents

    Oweis, Salah; D'Ussel, Louis; Chagnon, Guy; Zuhowski, Michael; Sack, Tim; Laucournet, Gaullume; Jackson, Edward J.

    2002-06-04

    A stand alone battery module including: (a) a mechanical configuration; (b) a thermal management configuration; (c) an electrical connection configuration; and (d) an electronics configuration. Such a module is fully interchangeable in a battery pack assembly, mechanically, from the thermal management point of view, and electrically. With the same hardware, the module can accommodate different cell sizes and, therefore, can easily have different capacities. The module structure is designed to accommodate the electronics monitoring, protection, and printed wiring assembly boards (PWAs), as well as to allow airflow through the module. A plurality of modules may easily be connected together to form a battery pack. The parts of the module are designed to facilitate their manufacture and assembly.

  5. Physiological and behavioral responses in Drosophila melanogaster to odorants present at different plant maturation stages.

    PubMed

    Versace, Elisabetta; Eriksson, Anna; Rocchi, Federico; Castellan, Irene; Sgadò, Paola; Haase, Albrecht

    2016-09-01

    The fruit fly Drosophila melanogaster feeds and oviposits on fermented fruit, hence its physiological and behavioral responses are expected to be tuned to odorants abundant during later stages of fruit maturation. We used a population of about two-hundred isogenic lines of D. melanogaster to assay physiological responses (electroantennograms (EAG)) and behavioral correlates (preferences and choice ratio) to odorants found at different stages of fruit maturation. We quantified electrophysiological and behavioral responses of D. melanogaster for the leaf compound β-cyclocitral, as well as responses to odorants mainly associated with later fruit maturation stages. Electrophysiological and behavioral responses were modulated by the odorant dose. For the leaf compound we observed a steep dose-response curve in both EAG and behavioral data and shallower curves for odorants associated with later stages of maturation. Our data show the connection between sensory and behavioral responses and are consistent with the specialization of D. melanogaster on fermented fruit and avoidance of high doses of compounds associated with earlier stages of maturation. Odor preferences were modulated in a non-additive way when flies were presented with two alternative odorants, and combinations of odorants elicited higher responses than single compounds.

  6. Sexual maturity in western Atlantic bluefin tuna

    PubMed Central

    Heinisch, Gilad; Rosenfeld, Hanna; Knapp, Jessica M.; Gordin, Hillel; Lutcavage, Molly E.

    2014-01-01

    We introduce a novel endocrine approach for assessing the unresolved matter of the timing of sexual maturation in western Atlantic bluefin tuna (ABFT), a highly migratory population whose status remains uncertain. Ratios of follicle stimulating hormone to luteinizing hormone, a sexual maturity indicator, in all ABFT ≥134 cm curved fork length (CFL) were <0.4, similar to Mediterranean spawners, indicating that western ABFT mature at considerably smaller sizes and at a much younger age than currently assumed (≥185 cm CFL). PMID:25431301

  7. Module Evaluation

    DTIC Science & Technology

    2006-02-01

    various testing methodologies for the evaluation and characterization of Transmit /Receive (T/R) modules for phased array radars. Discussed are techniques...for characterizing T/R modules in transmit and receive modes under ideal and emulated operation environments. Further, techniques for life testing...characteristics of T/R modules developed during the early and mid 1980’s. Data provided shows the performance in terms of gain and phase for both transmit

  8. 7 CFR 51.1218 - Mature.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Peaches Definitions § 51.1218 Mature. “Mature” means that the peach has reached the stage of growth which will ensure a proper completion of...

  9. 7 CFR 51.1218 - Mature.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Peaches Definitions § 51.1218 Mature. “Mature” means that the peach has reached the stage of growth which will ensure a proper completion of...

  10. 38 CFR 7.7 - Maturity.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... policy as a death claim or otherwise (SSCRA, as amended) will not include a termination or maturity of a... approval by the Department of Veterans Affairs. The statement of account will include the rate of...

  11. 38 CFR 7.7 - Maturity.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... policy as a death claim or otherwise (SSCRA, as amended) will not include a termination or maturity of a... approval by the Department of Veterans Affairs. The statement of account will include the rate of...

  12. 38 CFR 7.7 - Maturity.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... policy as a death claim or otherwise (SSCRA, as amended) will not include a termination or maturity of a... approval by the Department of Veterans Affairs. The statement of account will include the rate of...

  13. 7 CFR 1710.115 - Final maturity.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... maturities for loans for the implementation of programs for demand side management and energy resource conservation and on and off grid renewable energy sources not owned by the borrower will be determined by...

  14. Structure, function and dynamics in adenovirus maturation.

    PubMed

    Mangel, Walter F; San Martín, Carmen

    2014-11-21

    Here we review the current knowledge on maturation of adenovirus, a non-enveloped icosahedral eukaryotic virus. The adenovirus dsDNA genome fills the capsid in complex with a large amount of histone-like viral proteins, forming the core. Maturation involves proteolytic cleavage of several capsid and core precursor proteins by the viral protease (AVP). AVP uses a peptide cleaved from one of its targets as a "molecular sled" to slide on the viral genome and reach its substrates, in a remarkable example of one-dimensional chemistry. Immature adenovirus containing the precursor proteins lacks infectivity because of its inability to uncoat. The immature core is more compact and stable than the mature one, due to the condensing action of unprocessed core polypeptides; shell precursors underpin the vertex region and the connections between capsid and core. Maturation makes the virion metastable, priming it for stepwise uncoating by facilitating vertex release and loosening the condensed genome and its attachment to the icosahedral shell. The packaging scaffold protein L1 52/55k is also a substrate for AVP. Proteolytic processing of L1 52/55k disrupts its interactions with other virion components, providing a mechanism for its removal during maturation. Finally, possible roles for maturation of the terminal protein are discussed.

  15. Structure, function and dynamics in adenovirus maturation

    DOE PAGES

    Mangel, Walter F.; San Martín, Carmen

    2014-11-21

    Here we review the current knowledge on maturation of adenovirus, a non-enveloped icosahedral eukaryotic virus. The adenovirus dsDNA genome fills the capsid in complex with a large amount of histone-like viral proteins, forming the core. Maturation involves proteolytic cleavage of several capsid and core precursor proteins by the viral protease (AVP). AVP uses a peptide cleaved from one of its targets as a “molecular sled” to slide on the viral genome and reach its substrates, in a remarkable example of one-dimensional chemistry. Immature adenovirus containing the precursor proteins lacks infectivity because of its inability to uncoat. The immature core ismore » more compact and stable than the mature one, due to the condensing action of unprocessed core polypeptides; shell precursors underpin the vertex region and the connections between capsid and core. Maturation makes the virion metastable, priming it for stepwise uncoating by facilitating vertex release and loosening the condensed genome and its attachment to the icosahedral shell. The packaging scaffold protein L1 52/55k is also a substrate for AVP. Proteolytic processing of L1 52/55k disrupts its interactions with other virion components, providing a mechanism for its removal during maturation. In conclusion, possible roles for maturation of the terminal protein are discussed.« less

  16. Structure, Function and Dynamics in Adenovirus Maturation

    PubMed Central

    Mangel, Walter F.; San Martín, Carmen

    2014-01-01

    Here we review the current knowledge on maturation of adenovirus, a non-enveloped icosahedral eukaryotic virus. The adenovirus dsDNA genome fills the capsid in complex with a large amount of histone-like viral proteins, forming the core. Maturation involves proteolytic cleavage of several capsid and core precursor proteins by the viral protease (AVP). AVP uses a peptide cleaved from one of its targets as a “molecular sled” to slide on the viral genome and reach its substrates, in a remarkable example of one-dimensional chemistry. Immature adenovirus containing the precursor proteins lacks infectivity because of its inability to uncoat. The immature core is more compact and stable than the mature one, due to the condensing action of unprocessed core polypeptides; shell precursors underpin the vertex region and the connections between capsid and core. Maturation makes the virion metastable, priming it for stepwise uncoating by facilitating vertex release and loosening the condensed genome and its attachment to the icosahedral shell. The packaging scaffold protein L1 52/55k is also a substrate for AVP. Proteolytic processing of L1 52/55k disrupts its interactions with other virion components, providing a mechanism for its removal during maturation. Finally, possible roles for maturation of the terminal protein are discussed. PMID:25421887

  17. Structure, function and dynamics in adenovirus maturation

    SciTech Connect

    Mangel, Walter F.; San Martín, Carmen

    2014-11-21

    Here we review the current knowledge on maturation of adenovirus, a non-enveloped icosahedral eukaryotic virus. The adenovirus dsDNA genome fills the capsid in complex with a large amount of histone-like viral proteins, forming the core. Maturation involves proteolytic cleavage of several capsid and core precursor proteins by the viral protease (AVP). AVP uses a peptide cleaved from one of its targets as a “molecular sled” to slide on the viral genome and reach its substrates, in a remarkable example of one-dimensional chemistry. Immature adenovirus containing the precursor proteins lacks infectivity because of its inability to uncoat. The immature core is more compact and stable than the mature one, due to the condensing action of unprocessed core polypeptides; shell precursors underpin the vertex region and the connections between capsid and core. Maturation makes the virion metastable, priming it for stepwise uncoating by facilitating vertex release and loosening the condensed genome and its attachment to the icosahedral shell. The packaging scaffold protein L1 52/55k is also a substrate for AVP. Proteolytic processing of L1 52/55k disrupts its interactions with other virion components, providing a mechanism for its removal during maturation. In conclusion, possible roles for maturation of the terminal protein are discussed.

  18. Color back projection for fruit maturity evaluation

    NASA Astrophysics Data System (ADS)

    Zhang, Dong; Lee, Dah-Jye; Desai, Alok

    2013-12-01

    In general, fruits and vegetables such as tomatoes and dates are harvested before they fully ripen. After harvesting, they continue to ripen and their color changes. Color is a good indicator of fruit maturity. For example, tomatoes change color from dark green to light green and then pink, light red, and dark red. Assessing tomato maturity helps maximize its shelf life. Color is used to determine the length of time the tomatoes can be transported. Medjool dates change color from green to yellow, and the orange, light red and dark red. Assessing date maturity helps determine the length of drying process to help ripen the dates. Color evaluation is an important step in the processing and inventory control of fruits and vegetables that directly affects profitability. This paper presents an efficient color back projection and image processing technique that is designed specifically for real-time maturity evaluation of fruits. This color processing method requires very simple training procedure to obtain the frequencies of colors that appear in each maturity stage. This color statistics is used to back project colors to predefined color indexes. Fruit maturity is then evaluated by analyzing the reprojected color indexes. This method has been implemented and used for commercial production.

  19. Comparison of maturity based on steroid and vanadyl porphyrin parameters: A new vanadyl porphyrin maturity parameter for higher maturities

    NASA Astrophysics Data System (ADS)

    Sundararaman, Padmanabhan; Moldowan, J. Michael

    1993-03-01

    Correlations are demonstrated between steroid maturity parameters and the porphyrin maturity parameter (PMP) which is based on the ratio of specific vanadyl porphyrins C 28E /(C 28E + C 32D) measured by HPLC. Measurements from a global selection of > 100 rock extracts and oils show that PMP parallels changes in the C 29-sterane 20S/(20S + 20R) and tri/(tri + mono) aromatic steroid ratios, and that all three parameters appear to attain their maximum values at similar maturity levels. The triaromatic steroid side chain cracking parameter, TA I/(I + II), reaches approximately 20% of its maximum value when PMP has reached 100%. These results suggest that PMP is effective in the early to peak portion of the oil window. A new parameter, PMP-2, based on changes in the relative concentrations of two peaks in the HPLC fingerprint (vanadyl "etio" porphyrins), appears effective in assessing the maturity of source rocks beyond peak oil generation. In combination with PMP this parameter extends the effective range of vanadyl porphyrins parameters to higher maturities as demonstrated by a suite of oils from the Oriente Basin, Ecuador, South America.

  20. Adolescent Emotional Maturation through Divergent Models of Brain Organization.

    PubMed

    Oron Semper, Jose V; Murillo, Jose I; Bernacer, Javier

    2016-01-01

    In this article we introduce the hypothesis that neuropsychological adolescent maturation, and in particular emotional management, may have opposing explanations depending on the interpretation of the assumed brain architecture, that is, whether a componential computational account (CCA) or a dynamic systems perspective (DSP) is used. According to CCA, cognitive functions are associated with the action of restricted brain regions, and this association is temporally stable; by contrast, DSP argues that cognitive functions are better explained by interactions between several brain areas, whose engagement in specific functions is temporal and context-dependent and based on neural reuse. We outline the main neurobiological facts about adolescent maturation, focusing on the neuroanatomical and neurofunctional processes associated with adolescence. We then explain the importance of emotional management in adolescent maturation. We explain the interplay between emotion and cognition under the scope of CCA and DSP, both at neural and behavioral levels. Finally, we justify why, according to CCA, emotional management is understood as regulation, specifically because the cognitive aspects of the brain are in charge of regulating emotion-related modules. However, the key word in DSP is integration, since neural information from different brain areas is integrated from the beginning of the process. Consequently, although the terms should not be conceptually confused, there is no cognition without emotion, and vice versa. Thus, emotional integration is not an independent process that just happens to the subject, but a crucial part of personal growth. Considering the importance of neuropsychological research in the development of educational and legal policies concerning adolescents, we intend to expose that the holistic view of adolescents is dependent on whether one holds the implicit or explicit interpretation of brain functioning.

  1. Adolescent Emotional Maturation through Divergent Models of Brain Organization

    PubMed Central

    Oron Semper, Jose V.; Murillo, Jose I.; Bernacer, Javier

    2016-01-01

    In this article we introduce the hypothesis that neuropsychological adolescent maturation, and in particular emotional management, may have opposing explanations depending on the interpretation of the assumed brain architecture, that is, whether a componential computational account (CCA) or a dynamic systems perspective (DSP) is used. According to CCA, cognitive functions are associated with the action of restricted brain regions, and this association is temporally stable; by contrast, DSP argues that cognitive functions are better explained by interactions between several brain areas, whose engagement in specific functions is temporal and context-dependent and based on neural reuse. We outline the main neurobiological facts about adolescent maturation, focusing on the neuroanatomical and neurofunctional processes associated with adolescence. We then explain the importance of emotional management in adolescent maturation. We explain the interplay between emotion and cognition under the scope of CCA and DSP, both at neural and behavioral levels. Finally, we justify why, according to CCA, emotional management is understood as regulation, specifically because the cognitive aspects of the brain are in charge of regulating emotion-related modules. However, the key word in DSP is integration, since neural information from different brain areas is integrated from the beginning of the process. Consequently, although the terms should not be conceptually confused, there is no cognition without emotion, and vice versa. Thus, emotional integration is not an independent process that just happens to the subject, but a crucial part of personal growth. Considering the importance of neuropsychological research in the development of educational and legal policies concerning adolescents, we intend to expose that the holistic view of adolescents is dependent on whether one holds the implicit or explicit interpretation of brain functioning. PMID:27602012

  2. Transcriptional profiling of dendritic cells matured in different osmolarities.

    PubMed

    Chessa, Federica; Hielscher, Thomas; Mathow, Daniel; Gröne, Hermann-Josef; Popovic, Zoran V

    2016-03-01

    Tissue-specific microenvironments shape the fate of mononuclear phagocytes [1-3]. Interstitial osmolarity is a tissue biophysical parameter which considerably modulates the phenotype and function of dendritic cells [4]. In the present report we provide a detailed description of our experimental workflow and bioinformatic analysis applied to our gene expression dataset (GSE72174), aiming to investigate the influence of different osmolarity conditions on the gene expression signature of bone marrow-derived dendritic cells. We established a cell culture system involving murine bone marrow cells, cultured under different NaCl-induced osmolarity conditions in the presence of the dendritic cell growth factor GM-CSF. Gene expression analysis was applied to mature dendritic cells (day 7) developed in different osmolarities, with and without prior stimulation with the TLR2/4 ligand LPS.

  3. Source rock maturation, San Juan sag

    SciTech Connect

    Gries, R.R.; Clayton, J.L.

    1989-09-01

    Kinetic modeling for thermal histories was simulated for seven wells in the San Juan sag honoring measured geochemical data. Wells in the area of Del Norte field (Sec. 9, T40N, R5E), where minor production has been established from an igneous sill reservoir, show that the Mancos Shale source rocks are in the mature oil generation window as a combined result of high regional heat flow and burial by approximately 2,700 m of Oligocene volcanic rocks. Maturation was relatively recent for this area and insignificant during Laramide subsidence. In the vicinity of Gramps field (Sec. 24, T33N, R2E) on the southwest flank of the San Juan sag, these same source rocks are exposed due to erosion of the volcanic cover but appear to have undergone a similar maturation history. At the north and south margins of the sag, two wells (Champlin 34A-13, Sec. 13, T35N, R4.5E; and Champlin 24A-1, Sec. 1, T44N, R5E) were analyzed and revealed that although the regional heat flow was probably similar to other wells, the depth of burial was insufficient to cause maturation (except where intruded by thick igneous sills that caused localized maturation). The Meridian Oil 23-17 South Fork well (Sec. 17, T39N, R4E) was drilled in a deeper part of the San Juan sag, and source rocks were intruded by numerous igneous sills creating a complex maturation history that includes overmature rocks in the lowermost Mancos Shale, possible CO{sub 2} generation from the calcareous Niobrara Member of the Mancos Shale, and mature source rocks in the upper Mancos Shale.

  4. Lysosomal protease expression in mature enamel.

    PubMed

    Tye, Coralee E; Lorenz, Rachel L; Bartlett, John D

    2009-01-01

    The enamel matrix proteins (amelogenin, enamelin and ameloblastin) are degraded by matrix metalloproteinase-20 and kallikrein-4 during enamel development and mature enamel is virtually protein free. The precise mechanism of removal and degradation of the enamel protein cleavage products from the matrix, however, remains poorly understood. It has been proposed that receptor-mediated endocytosis allows for the cleaved proteins to be removed from the matrix during enamel formation and then transported to the lysosome for further degradation. This study aims to identify lysosomal proteases that are present in maturation-stage enamel organ. RNA from first molars of 11-day-old mice was collected and expression was initially assessed by RT-PCR and then quantified by qPCR. The pattern of expression of selected proteases was assessed by immunohistochemical staining of demineralized mouse incisors. With the exception of cathepsin G, all lysosomal proteases assessed were expressed in maturation-stage enamel organ. Identified proteases included cathepsins B, D, F, H, K, L, O, S and Z. Tripeptidyl peptidases I and II as well as dipeptidyl peptidases I, II, III and IV were also found to be expressed. Immunohistochemical staining confirmed that the maturation-stage ameloblasts express cathepsins L and S and tripeptidyl peptidase II. Our results suggest that the ameloblasts are enriched by a large number of lysosomal proteases at maturation that are likely involved in the degradation of the organic matrix.

  5. Maturity Model for Advancing Smart Grid Interoperability

    SciTech Connect

    Knight, Mark; Widergren, Steven E.; Mater, J.; Montgomery, Austin

    2013-10-28

    Abstract—Interoperability is about the properties of devices and systems to connect and work properly. Advancing interoperability eases integration and maintenance of the resulting interconnection. This leads to faster integration, lower labor and component costs, predictability of projects and the resulting performance, and evolutionary paths for upgrade. When specifications are shared and standardized, competition and novel solutions can bring new value streams to the community of stakeholders involved. Advancing interoperability involves reaching agreement for how things join at their interfaces. The quality of the agreements and the alignment of parties involved in the agreement present challenges that are best met with process improvement techniques. The GridWise® Architecture Council (GWAC) sponsored by the United States Department of Energy is supporting an effort to use concepts from capability maturity models used in the software industry to advance interoperability of smart grid technology. An interoperability maturity model has been drafted and experience is being gained through trials on various types of projects and community efforts. This paper describes the value and objectives of maturity models, the nature of the interoperability maturity model and how it compares with other maturity models, and experiences gained with its use.

  6. Genome-wide association mapping of flowering time and maturity dates in early mature soybean germplasm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean (Glycine max L. Merr.) is a photoperiod-sensitive and short-day major crop grown worldwide. Days to flowering (DTF) and maturity (DTM) are two traits affecting soybean adaptability and yield. Some genes conditioning soybean flowering and maturity have been recently characterized. However, ...

  7. Need for speed: Sexual maturation precedes social maturation in gray mouse lemurs.

    PubMed

    Hohenbrink, Sarah; Zimmermann, Elke; Radespiel, Ute

    2015-10-01

    The life history of mammals underlies a fast-slow continuum, ranging from "slow" species with large body size, delayed sexual maturation, low fertility, and long lifespan, to "fast" species showing the opposite traits. Primates fall into the "slow" category, considering their relatively low offspring numbers and delayed juvenile development. However, social and sexual maturation processes do not necessarily have to be completed simultaneously. The comparison of the timeframes for sexual and social maturation is largely lacking for primates, with the prominent exception of humans. Here, we compare both maturation processes in a basal primate, the gray mouse lemur, which ranges in many aspects at the fast end of the slow-fast life history continuum among primates. We compared the patterns and frequencies of various social and solitary behaviors in young adults (YA, 12-13 months old) and older individuals (A, ≥2 years) of both sexes outside estrus. Observations were conducted during mix-sexed dyadic encounter experiments under controlled captive conditions (eight dyads per age class). Results indicate that although all young adults were sexually mature, social maturation was not yet completed in all behavioral domains: Age-dependent differences were found in the number of playing dyads, female marking behavior, female aggression, and social tolerance. Thus, this study provides a first indication that social maturation lags behind sexual maturation in an ancestral nocturnal primate model, indicating that these two developmental schemes may have been decoupled early and throughout the primate lineage.

  8. Modulated Entry

    NASA Technical Reports Server (NTRS)

    Grant, Frederick C.

    1960-01-01

    The technique of modulation, or variable coefficients, is discussed and the analytical formulation is reviewed. Representative numerical results of the use of modulation are shown for the lifting and nonlifting cases. These results include the effects of modulation on peak acceleration, entry corridor, and heat absorption. Results are given for entry at satellite speed and escape speed. The indications are that coefficient modulation on a vehicle with good lifting capability offers the possibility of sizable loading reductions or, alternatively, wider corridors; thus, steep entries become practical from the loading standpoint. The amount of steepness depends on the acceptable heating penalty. The price of sizable fractions of the possible gains does not appear to be excessive.

  9. Genetic transformation of mature citrus plants.

    PubMed

    Cervera, Magdalena; Juárez, José; Navarro, Luis; Peña, Leandro

    2005-01-01

    Most woody fruit species have long juvenile periods that drastically prolong the time required to analyze mature traits. Evaluation of characteristics related to fruits is a requisite to release any new variety into the market. Because of a decline in regenerative and transformation potential, genetic transformation procedures usually employ juvenile material as the source of plant tissue, therefore resulting in the production of juvenile plants. Direct transformation of mature material could ensure the production of adult transgenic plants, bypassing in this way the juvenile phase. Invigoration of the source adult material, establishment of adequate transformation and regeneration conditions, and acceleration of plant development through grafting allowed us to produce transgenic mature sweet orange trees flowering and bearing fruits in a short time period.

  10. Elevated Social Anxiety among Early Maturing Girls

    PubMed Central

    Blumenthal, Heidemarie; Leen-Feldner, Ellen W.; Babson, Kimberly A.; Gahr, Jessica L.; Trainor, Casey D.; Frala, Jamie L.

    2012-01-01

    Adolescence is a key period in terms of the development of anxiety psychopathology. An emerging literature suggests that early pubertal maturation is associated with enhanced vulnerability for anxiety symptomatology, although few studies have examined this association with regard to social anxiety. Accordingly, the current study was designed to further elucidate the relation between pubertal timing and social anxiety, with a focus on clarifying the role of gender. Participants were 138 adolescents (ages 12-17 years) recruited from the general community. Level of social anxiety was examined as a function of gender and within-sample pubertal timing. As expected, early-maturing girls evidenced significantly higher social anxiety as compared to on-time girls and early-maturing boys, and no other differences were found as a function of gender or developmental timing. Findings and future directions are discussed in terms of forwarding developmentally-sensitive models of social anxiety etiology and prevention. PMID:21604866

  11. Strength, flexibility, and maturity in adolescent athletes.

    PubMed

    Pratt, M

    1989-05-01

    The relationship between lower-extremity strength and flexibility and maturational status as measured by Tanner staging (TS) was assessed in 84 male high school athletes. The sum of one-repetition maximum lifts for knee extension and flexion was determined and flexibility was measured with the American Alliance of Health, Physical Education, Recreation, and Dance sit-and-reach test. Chronologic age, body weight, and percent fat were also recorded. Strength and flexibility were compared for each maturational and chronologic age category. Maturational age was better correlated with strength and flexibility than was chronologic age. All correlations were significant. Multiple regression analysis demonstrated significant correlations of TS and age with strength and flexibility. Tanner staging had greater predictive value than age for strength and flexibility. After adjusting for age, the relationship between TS and strength remained significant.

  12. Stacking the odds for Golgi cisternal maturation

    PubMed Central

    Mani, Somya; Thattai, Mukund

    2016-01-01

    What is the minimal set of cell-biological ingredients needed to generate a Golgi apparatus? The compositions of eukaryotic organelles arise through a process of molecular exchange via vesicle traffic. Here we statistically sample tens of thousands of homeostatic vesicle traffic networks generated by realistic molecular rules governing vesicle budding and fusion. Remarkably, the plurality of these networks contain chains of compartments that undergo creation, compositional maturation, and dissipation, coupled by molecular recycling along retrograde vesicles. This motif precisely matches the cisternal maturation model of the Golgi, which was developed to explain many observed aspects of the eukaryotic secretory pathway. In our analysis cisternal maturation is a robust consequence of vesicle traffic homeostasis, independent of the underlying details of molecular interactions or spatial stacking. This architecture may have been exapted rather than selected for its role in the secretion of large cargo. DOI: http://dx.doi.org/10.7554/eLife.16231.001 PMID:27542195

  13. Calcium ion currents mediating oocyte maturation events

    PubMed Central

    Tosti, Elisabetta

    2006-01-01

    During maturation, the last phase of oogenesis, the oocyte undergoes several changes which prepare it to be ovulated and fertilized. Immature oocytes are arrested in the first meiotic process prophase, that is morphologically identified by a germinal vesicle. The removal of the first meiotic block marks the initiation of maturation. Although a large number of molecules are involved in complex sequences of events, there is evidence that a calcium increase plays a pivotal role in meiosis re-initiation. It is well established that, during this process, calcium is released from the intracellular stores, whereas less is known on the role of external calcium entering the cell through the plasma membrane ion channels. This review is focused on the functional role of calcium currents during oocyte maturation in all the species, from invertebrates to mammals. The emerging role of specific L-type calcium channels will be discussed. PMID:16684344

  14. An unexpected twist in viral capsid maturation

    SciTech Connect

    Gertsman, Ilya; Gan, Lu; Guttman, Miklos; Lee, Kelly; Speir, Jeffrey A.; Duda, Robert L.; Hendrix, Roger W.; Komives, Elizabeth A.; Johnson, John E.

    2009-04-14

    Lambda-like double-stranded (ds) DNA bacteriophage undergo massive conformational changes in their capsid shell during the packaging of their viral genomes. Capsid shells are complex organizations of hundreds of protein subunits that assemble into intricate quaternary complexes that ultimately are able to withstand over 50 atm of pressure during genome packaging. The extensive integration between subunits in capsids requires the formation of an intermediate complex, termed a procapsid, from which individual subunits can undergo the necessary refolding and structural rearrangements needed to transition to the more stable capsid. Although various mature capsids have been characterized at atomic resolution, no such procapsid structure is available for a dsDNA virus or bacteriophage. Here we present a procapsid X-ray structure at 3.65 {angstrom} resolution, termed prohead II, of the lambda-like bacteriophage HK97, the mature capsid structure of which was previously solved to 3.44 {angstrom}. A comparison of the two largely different capsid forms has unveiled an unprecedented expansion mechanism that describes the transition. Crystallographic and hydrogen/deuterium exchange data presented here demonstrate that the subunit tertiary structures are significantly different between the two states, with twisting and bending motions occurring in both helical and -sheet regions. We also identified subunit interactions at each three-fold axis of the capsid that are maintained throughout maturation. The interactions sustain capsid integrity during subunit refolding and provide a fixed hinge from which subunits undergo rotational and translational motions during maturation. Previously published calorimetric data of a closely related bacteriophage, P22, showed that capsid maturation was an exothermic process that resulted in a release of 90 kJ mol{sup -1} of energy. We propose that the major tertiary changes presented in this study reveal a structural basis for an exothermic

  15. On the maturation rate of the neutrophil.

    PubMed

    Zajicek, G; Shohat, M; Polliack, A

    1984-05-01

    Fifty-three maturing bone marrow cells of the granulocyte cell series stained with Giemsa stain and magnified 1,000 times were scanned by a "computerized microscope" consisting of a LSI-11/23 microprocessor and a black-and-white video camera attached to a "frame grabber ." Each sampled cell was digitized into 70 X 70 pixels, each pixel representing 0.04 micron of the real image. The pixel gray values ranged between 0 and 255. Zero stood for white, 255 represented black, while the numbers in between stood for the various shades of gray. The cells represented six different stages of granulocytic maturation: myeloblast, promyelocyte, myelocyte, metamyelocyte , band form, and polymorphonuclear granulocyte. A discriminant analysis program selected 19 features best distinguishing between the six different cell types and computed five canonical discriminant functions defining a Space in which maturation was studied. In the Space, distance between two cells serves as a measure of similarity. The closer two cells are, the more similar they are and vice versa. This measure was applied here to express the degree of similarity between the neutrophil maturation classes, and since they represent states in the neutrophil life history, it is applicable also as a yardstick for the quantitation of differentiation. In the Space, the life history of a cell is represented by a trajectory originating in the myeloblast and terminating in the granulocyte state. Displacement along the trajectory represents cell maturation that is expressed relatively to the least differentiated state of the myeloblast. The further a cell from this state the more mature it is. The same yardstick also serves for differentiation rate estimates represented in the Space by displacement velocities that are derived from the known "transit times" of a cell in each state. The methodology is also applied for cell production estimates. Unlike other "computerized microscopes" serving for cell classification, the

  16. Management and Breeding Soundness of Mature Bulls.

    PubMed

    Palmer, Colin W

    2016-07-01

    Mature bulls must be fed a balanced ration, vaccinated appropriately, and undergo a breeding soundness evaluation to ensure they meet what is required of a short, but intense breeding season. To be classified as a satisfactory potential breeder, minimum standards for physical soundness, scrotal circumference, sperm motility, and sperm morphology must be achieved using an accepted bull-breeding soundness evaluation format. Sperm production requires approximately 70 days. Heat and stress are the most common insults to spermatogenesis, causing an increase in morphologic abnormalities with obesity-associated scrotal fat accumulation being the most frequent cause of elevated testicular temperature in mature bulls.

  17. Sexual maturation in East German girls.

    PubMed

    Engelhardt, L; Willers, B; Pelz, L

    1995-12-01

    According to the internationally accepted classification (Tanner, 1962; van Wieringen, 1971), sexual maturation was investigated in 8703 healthy East German girls by means of the status quo method and probit regression analysis. The third, 50th and 97th centiles were calculated for the development of breasts, axillary and pubic hair, and the shape of the hips. The findings were compared with those of recent studies from different European countries. Special attention was paid to the stages at the beginning and at the end of sexual maturation, e.g. B2/B5, AH2/AH3, etc.

  18. Sexual maturation in East German boys.

    PubMed

    Willers, B; Engelhardt, L; Pelz, L

    1996-07-01

    According to the internationally accepted classification, sexual maturation was investigated in 8685 healthy East German boys by means of the status quo method and the probit regression analysis. The 3rd, 50th and 97th centiles were calculated for the development of both the male external genitalia and pubic and axillary hairs. The findings are in line with those of recent studies from different European countries. Special attention was paid to the stages at the beginning and at the end of sexual maturation, e.g. B 2, B 5; AH2, AH3; PH 2, PH5/6, etc.

  19. Activation-Dependent Rapid Postsynaptic Clustering of Glycine Receptors in Mature Spinal Cord Neurons

    PubMed Central

    Eto, Kei; Murakoshi, Hideji; Watanabe, Miho; Hirata, Hiromi; Moorhouse, Andrew J.; Ishibashi, Hitoshi

    2017-01-01

    Abstract Inhibitory synapses are established during development but continue to be generated and modulated in strength in the mature nervous system. In the spinal cord and brainstem, presynaptically released inhibitory neurotransmitter dominantly switches from GABA to glycine during normal development in vivo. While presynaptic mechanisms of the shift of inhibitory neurotransmission are well investigated, the contribution of postsynaptic neurotransmitter receptors to this shift is not fully elucidated. Synaptic clustering of glycine receptors (GlyRs) is regulated by activation-dependent depolarization in early development. However, GlyR activation induces hyperpolarization after the first postnatal week, and little is known whether and how presynaptically released glycine regulates postsynaptic receptors in a depolarization-independent manner in mature developmental stage. Here we developed spinal cord neuronal culture of rodents using chronic strychnine application to investigate whether initial activation of GlyRs in mature stage could change postsynaptic localization of GlyRs. Immunocytochemical analyses demonstrate that chronic blockade of GlyR activation until mature developmental stage resulted in smaller clusters of postsynaptic GlyRs that could be enlarged upon receptor activation for 1 h in the mature stage. Furthermore, live cell-imaging techniques show that GlyR activation decreases its lateral diffusion at synapses, and this phenomenon is dependent on PKC, but neither Ca2+ nor CaMKII activity. These results suggest that the GlyR activation can regulate receptor diffusion and cluster size at inhibitory synapses in mature stage, providing not only new insights into the postsynaptic mechanism of shifting inhibitory neurotransmission but also the inhibitory synaptic plasticity in mature nervous system. PMID:28197549

  20. 7 CFR 51.312 - Mature.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Standards for Grades of Apples Definitions § 51.312 Mature. “Mature” means that the apples have reached the... apple becomes overripe it will show varying degrees of firmness, depending upon the stage of the ripening process. The following terms are used for describing different stages of firmness of apples:...

  1. 7 CFR 51.312 - Mature.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Standards for Grades of Apples Definitions § 51.312 Mature. “Mature” means that the apples have reached the... apple becomes overripe it will show varying degrees of firmness, depending upon the stage of the ripening process. The following terms are used for describing different stages of firmness of apples:...

  2. 7 CFR 51.312 - Mature.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Standards for Grades of Apples Definitions § 51.312 Mature. “Mature” means that the apples have reached the... apple becomes overripe it will show varying degrees of firmness, depending upon the stage of the ripening process. The following terms are used for describing different stages of firmness of apples:...

  3. Thermal maturity of carboniferous strata, Ouachita Mountains

    SciTech Connect

    Houseknecht, D.W.; Matthews, S.M.

    1985-03-01

    The Ouachita Mountains, a relatively untested, potential hydrocarbon province, contain a thick Paleozoic section of apparently favorable source beds, reservoir beds, and trap configurations. To estimate the thermal maturity of these strata, vitrinite reflectance was measured on 89 samples collected mostly from Carboniferous rocks from throughout the Ouachita outcrop area.

  4. Skeletal maturation evaluation using cervical vertebrae.

    PubMed

    Hassel, B; Farman, A G

    1995-01-01

    Lateral cephalometric and left hand-wrist radiographs from the Bolton-Brush Growth Center at Case Western Reserve University were reviewed a posteriori to develop a cervical vertebrae maturation index (CVMI). By using the lateral profiles of the second, third and fourth cervical vertebrae, it was possible to develop a reliable ranking of patients according to the potential for future adolescent growth potential.

  5. 7 CFR 989.213 - Maturity dockage.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... between handler and tenderer, Natural (sun-dried) Seedless, Golden Seedless, Dipped Seedless, Monukka... dockage table applicable to lots of Natural (sun-dried) Seedless, Golden Seedless, Dipped Seedless... dockage factor for the preceding increment. (c) Maturity dockage table applicable to lots of Natural...

  6. 7 CFR 989.213 - Maturity dockage.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... between handler and tenderer, Natural (sun-dried) Seedless, Golden Seedless, Dipped Seedless, Monukka... dockage table applicable to lots of Natural (sun-dried) Seedless, Golden Seedless, Dipped Seedless... dockage factor for the preceding increment. (c) Maturity dockage table applicable to lots of Natural...

  7. 7 CFR 989.213 - Maturity dockage.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... between handler and tenderer, Natural (sun-dried) Seedless, Golden Seedless, Dipped Seedless, Monukka... dockage table applicable to lots of Natural (sun-dried) Seedless, Golden Seedless, Dipped Seedless... dockage factor for the preceding increment. (c) Maturity dockage table applicable to lots of Natural...

  8. 7 CFR 989.213 - Maturity dockage.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... between handler and tenderer, Natural (sun-dried) Seedless, Golden Seedless, Dipped Seedless, Monukka... dockage table applicable to lots of Natural (sun-dried) Seedless, Golden Seedless, Dipped Seedless... dockage factor for the preceding increment. (c) Maturity dockage table applicable to lots of Natural...

  9. 7 CFR 989.213 - Maturity dockage.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... between handler and tenderer, Natural (sun-dried) Seedless, Golden Seedless, Dipped Seedless, Monukka... dockage table applicable to lots of Natural (sun-dried) Seedless, Golden Seedless, Dipped Seedless... dockage factor for the preceding increment. (c) Maturity dockage table applicable to lots of Natural...

  10. Career Maturity: A Priority for Secondary Education

    ERIC Educational Resources Information Center

    Gonzalez, Manuel Alvarez

    2008-01-01

    This study reviews the current state of career maturity in secondary education--a period of education which is critical for development of this construct, when students are faced with ongoing academic and occupational decisions over the course of their studies. This paper is organized in three parts: first we focus on the concept, models,…

  11. Prenatal Antecedents of Newborn Neurological Maturation

    ERIC Educational Resources Information Center

    DiPietro, Janet A.; Kivlighan, Katie T.; Costigan, Kathleen A.; Rubin, Suzanne E.; Shiffler, Dorothy E.; Henderson, Janice L.; Pillion, Joseph P.

    2010-01-01

    Fetal neurobehavioral development was modeled longitudinally using data collected at weekly intervals from 24 to 38 weeks gestation in a sample of 112 healthy pregnancies. Predictive associations between 3 measures of fetal neurobehavioral functioning and their developmental trajectories to neurological maturation in the first weeks after birth…

  12. Late Maturation of Auditory Perceptual Learning

    ERIC Educational Resources Information Center

    Huyck, Julia Jones; Wright, Beverly A.

    2011-01-01

    Adults can improve their performance on many perceptual tasks with training, but when does the response to training become mature? To investigate this question, we trained 11-year-olds, 14-year-olds and adults on a basic auditory task (temporal-interval discrimination) using a multiple-session training regimen known to be effective for adults. The…

  13. 7 CFR 51.1158 - Mature.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... same meaning assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February 12, 1995. These orange maturity requirements are contained in the Florida Citrus Code, Chapter 601, Florida Statutes, Sections 601.19, and...

  14. 7 CFR 51.1823 - Mature.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February 12, 1995. These tangerine maturity requirements are contained in the Florida Citrus Code, Chapter 601, Florida Statutes, Sections 601.21, and...

  15. 7 CFR 51.1823 - Mature.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February 12, 1995. These tangerine maturity requirements are contained in the Florida Citrus Code, Chapter 601, Florida Statutes, Sections 601.21, and...

  16. 7 CFR 51.767 - Mature.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February 12, 1995. These grapefruit maturity requirements are contained in the Florida Citrus Code, Chapter 601, Florida Statutes, Sections 601.16, 601.17,...

  17. 7 CFR 51.1158 - Mature.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... same meaning assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February 12, 1995. These orange maturity requirements are contained in the Florida Citrus Code, Chapter 601, Florida Statutes, Sections 601.19, and...

  18. 7 CFR 51.1158 - Mature.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... same meaning assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February 12, 1995. These orange maturity requirements are contained in the Florida Citrus Code, Chapter 601, Florida Statutes, Sections 601.19, and...

  19. 7 CFR 51.767 - Mature.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February 12, 1995. These grapefruit maturity requirements are contained in the Florida Citrus Code, Chapter 601, Florida Statutes, Sections 601.16, 601.17,...

  20. 7 CFR 51.767 - Mature.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February 12, 1995. These grapefruit maturity requirements are contained in the Florida Citrus Code, Chapter 601, Florida Statutes, Sections 601.16, 601.17,...

  1. 7 CFR 51.1823 - Mature.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February 12, 1995. These tangerine maturity requirements are contained in the Florida Citrus Code, Chapter 601, Florida Statutes, Sections 601.21, and...

  2. Manual for the Employability Maturity Interview.

    ERIC Educational Resources Information Center

    Roessler, Richard; Bolton, Brian

    The Employability Maturity Interview (EMI) is a 10-item structured interview developed to assess readiness for the vocational rehabilitation planning process and the need for additional vocational exploration and employability services. The items deal with occupational choice, self-appraisal of abilities, self-appraisal of personality…

  3. Young Carers: Mature before Their Time

    ERIC Educational Resources Information Center

    Charles, Grant; Stainton, Tim; Marshall, Sheila

    2009-01-01

    There is a population of remarkable young people who may go unnoticed due to the absence of overt acting out behaviors. Often mature beyond their age, they are forced by family situations to assume care-giving roles which are usually the responsibility of parents and elders. Being placed prematurely in adult caring roles potentially may have both…

  4. Role of adenosine in oligodendrocyte precursor maturation

    PubMed Central

    Coppi, Elisabetta; Cellai, Lucrezia; Maraula, Giovanna; Dettori, Ilaria; Melani, Alessia; Pugliese, Anna Maria; Pedata, Felicita

    2015-01-01

    Differentiation and maturation of oligodendroglial cells are postnatal processes that involve specific morphological changes correlated with the expression of stage-specific surface antigens and functional voltage-gated ion channels. A small fraction of oligodendrocyte progenitor cells (OPCs) generated during development are maintained in an immature and slowly proliferative or quiescent state in the adult central nervous system (CNS) representing an endogenous reservoir of immature cells. Adenosine receptors are expressed by OPCs and a key role of adenosine in oligodendrocyte maturation has been recently recognized. As evaluated on OPC cultures, adenosine, by stimulating A1 receptors, promotes oligodendrocyte maturation and inhibits their proliferation; on the contrary, by stimulating A2A receptors, it inhibits oligodendrocyte maturation. A1 and A2A receptor-mediated effects are related to opposite modifications of outward delayed rectifying membrane K+ currents (IK) that are involved in the regulation of oligodendrocyte differentiation. Brain A1 and A2A receptors might represent new molecular targets for drugs useful in demyelinating pathologies, such as multiple sclerosis (MS), stroke and brain trauma. PMID:25964740

  5. Gene expression associated with tuber periderm maturation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Potato periderm maturation and associated resistance to tuber excoriation, i.e. skinning injury, is of scientific and agricultural importance because of the losses created by shrinkage, tuber market quality defects and infections. The cells and cellular changes responsible for the development of re...

  6. Teaching Copywriting Students about the Mature Market.

    ERIC Educational Resources Information Center

    Drewniany, Bonnie

    Advertising educators have a responsibility to make students aware of the importance of the mature market (older people) and to teach them methods to reach this group. An assignment in a copywriting class asked students to write and design ads to promote blue jeans to adults over 50. The assignment accomplished three things: (1) helped students…

  7. Black-White Differences in Psychosocial Maturity.

    ERIC Educational Resources Information Center

    Starr, B. James; And Others

    The present investigation reviews the racial comparison literature in order to make specific predictions about racial differences on the psychosocial maturity scale developed by Greenberger, Campbell, Sorensen, and O'Connor (1971). On the basis of this review, it was predicted that blacks would score lower than whites on the scale, and that this…

  8. Growth Goals, Maturity, and Well-Being

    ERIC Educational Resources Information Center

    Bauer, Jack J.; McAdams, Dan P.

    2004-01-01

    In 2 studies (125 college students and 51 adults), 2 forms of growth goals (exploratory and intrinsic) were compared with 2 forms of personality development (social-cognitive maturity and social-emotional well-being). Participants whose narratives of major life goals emphasized conceptual exploration were especially likely to have high levels of…

  9. Elevated Social Anxiety among Early Maturing Girls

    ERIC Educational Resources Information Center

    Blumenthal, Heidemarie; Leen-Feldner, Ellen W.; Babson, Kimberly A.; Gahr, Jessica L.; Trainor, Casey D.; Frala, Jamie L.

    2011-01-01

    Adolescence is a key period in terms of the development of anxiety psychopathology. An emerging literature suggests that early pubertal maturation is associated with enhanced vulnerability for anxiety symptomatology, although few studies have examined this association with regard to social anxiety. Accordingly, the current study was designed to…

  10. Firefighting Module

    NASA Technical Reports Server (NTRS)

    1978-01-01

    NASA and the U.S. Coast Guard are working jointly to develop a helicopter transportable firefighting module that can shave precious minutes in combating shipboard or harbor fires. The program was undertaken in 1975, after a series of disastrous fires on oil tankers indicated a need for a lightweight, self-contained system that could be moved quickly to the scene of a fire. A prototype module was delivered to the Coast Guard last year and service testing is under way. The compact module weighs little more than a ton but it contains everything needed to fight a fire. The key component is a high output pump, which delivers up to 2,000 gallons of sea water a minute; the pump can be brought up to maximum output in only one minute after turning on the power source, a small Allison gas turbine engine. The module also contains hose, a foam nozzle and a spray nozzle, three sets of protective clothing for firefighters, and fuel for three hours operation. Designed to be assembled without special tools, the module can be set up for operation in less than 20 minutes.

  11. Firefighting Module

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Aviation Power Supply's mobile firefighting module called Firefly II is mounted on a trailer pulled by a pickup truck. Trailer unit has two three- inch water cannons, and the pickup carries a six inch cannon. Completely self contained, module pumps 3,000 gallons of water a minute from hydrants or open bodies of water. Stream can go as far as 400 feet or can be employed in a high-loft mode to reach the tops of tall refinery towers. Compact Firefly II weighs only 2,500 pounds when fully fueled. Key component is a specially designed two stage pump. Power for the pump is generated by a gas turbine engine. Module also includes an electronic/pump controller, multiple hose connections, up to 1,500 feet of hose and fuel for four hours operation. Firefly trailer can be backed onto specially-built large fireboat.

  12. Firefighting Module

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Aviation Power Supply's mobile firefighting module called Firefly II is mounted on a trailer pulled by a pickup truck. Trailer unit has two three- inch water cannons, and the pickup carries a six inch cannon. Completely self contained, module pumps 3,000 gallons of water a minute from hydrants or open bodies of water. Stream can go as far as 400 feet or can be employed in a high-loft mode to reach the tops of tall refinery towers. Compact Firefly II weighs only 2,500 pounds when fully fueled. Key component is a specially designed two stage pump. Power for the pump is generated by a gas turbine engine. Module also includes an electronic/pump controller, multiple hose connections, up to 1,500 feet of hose and fuel for four hours operation. Firefly trailer can be backed onto specially-built large fireboat.

  13. Thermionic modules

    DOEpatents

    King, Donald B.; Sadwick, Laurence P.; Wernsman, Bernard R.

    2002-06-18

    Modules of assembled microminiature thermionic converters (MTCs) having high energy-conversion efficiencies and variable operating temperatures manufactured using MEMS manufacturing techniques including chemical vapor deposition. The MTCs incorporate cathode to anode spacing of about 1 micron or less and use cathode and anode materials having work functions ranging from about 1 eV to about 3 eV. The MTCs also exhibit maximum efficiencies of just under 30%, and thousands of the devices and modules can be fabricated at modest costs.

  14. Leveraging People-Related Maturity Issues for Achieving Higher Maturity and Capability Levels

    NASA Astrophysics Data System (ADS)

    Buglione, Luigi

    During the past 20 years Maturity Models (MM) become a buzzword in the ICT world. Since the initial Crosby's idea in 1979, plenty of models have been created in the Software & Systems Engineering domains, addressing various perspectives. By analyzing the content of the Process Reference Models (PRM) in many of them, it can be noticed that people-related issues have little weight in the appraisals of the capabilities of organizations while in practice they are considered as significant contributors in traditional process and organizational performance appraisals, as stressed instead in well-known Performance Management models such as MBQA, EFQM and BSC. This paper proposes some ways for leveraging people-related maturity issues merging HR practices from several types of maturity models into the organizational Business Process Model (BPM) in order to achieve higher organizational maturity and capability levels.

  15. [The assessment of modulated radiofrequence electromagnetic radiation on cognitive function in rats of different ages].

    PubMed

    Priakhin, E A; Triapitsyna, G A; Andreev, S S; Kolomiets, I A; Polevik, N D; Akleev, A V

    2007-01-01

    The modulated radiofrequence electromagnetic radiation influence on cognitive function of male uninbred Wister rat exposed at the age of sexual maturation (2 months) and at the age of morphofunctional maturity (3.5 months) was examined. Animals were subjected to pulse electromagnetic radiation (925 MHz) modulated as a GSM standard with the power density 1.2 mW/cm2 for 10 minutes every day for 12 days. At day 8 of exposure the cognitive function were examined with the Morris water maze. In the result of investigation it was determines that modulated radiofrequence electromagnetic radiation at the sexual maturation age did not affect the spatial learning and improve the visual orientation performance. Modulated radiofrequence electromagnetic exposure of animals at the sex maturity age did not affect the visual performance and improve the spatial performance of male rats.

  16. Diagnostic performance of dental maturity for identification of skeletal maturation phase.

    PubMed

    Perinetti, G; Contardo, L; Gabrieli, P; Baccetti, T; Di Lenarda, R

    2012-08-01

    The objective of this study is to analyse the diagnostic performance of the circumpubertal dental maturation phases for the identification of individual-specific skeletal maturation phases. A total of 354 healthy subjects, 208 females and 146 males (mean age, 11.1 ± 2.4 years; range, 6.8-17.1 years), were enrolled in the study. Dental maturity was assessed through the calcification stages from panoramic radiographs of the mandibular canine, the first and second premolars, and the second molar. Determination of skeletal maturity was according to the cervical vertebra maturation (CVM) method on lateral cephalograms. Diagnostic performances were evaluated according to the dental maturation stages for each tooth for the identification of the CVM stages and growth phases (as pre-pubertal, pubertal, and post-pubertal) using positive likelihood ratios (LHRs). A positive LHR threshold of 10 or more was considered for satisfactory reliability of any dental maturation stage for the identification of any of the CVM stages or growth phases. The positive LHRs were generally less than 2.0, with a few exceptions. These four teeth showed positive LHRs greater than 10 only for the identification of the pre-pubertal growth phase, with values from 10.8 for the second molar (stage E) to 39.3 for the first premolar (stage E). Dental maturation assessment is only useful for diagnosis of the pre-pubertal growth phase, and thus, precise information in relation to the timing of the onset of the growth spurt is not provided by these indices.

  17. Development and validation of the Eating Maturity Questionnaire: Preliminary findings.

    PubMed

    Potocka, Adrianna; Najder, Anna

    2016-10-01

    This article describes the development of the Eating Maturity Questionnaire, a self-reported measurement of eating maturity that initiates and gives direction to human eating behaviors. The Eating Maturity Questionnaire was designed to study individuals' biological and psychosocial motives for eating. The Eating Maturity Questionnaire is a 21-item tool with satisfactory psychometric values (Cronbach's α coefficients between 0.83 and 0.88) consisting of two subscales: Rational Eating and Psychosocial Maturity Eating Maturity Questionnaire results may be used to design programs that target eating behaviors and body mass modification.

  18. Modulation of lymphopoiesis

    SciTech Connect

    Rosse, C.

    1991-01-01

    During the current project period we have demonstrated correspondence between animal models and in vitro models of modulated lymphopoiesis. Our finding that G-CSF, a growth factor for neutrophil granulocytes, suppresses lymphopoiesis in long term bone marrow cultures (LTBMC) has important implications both for understanding the regulatory mechanisms of hemopoiesis and for clinical use of recombinant growth factors that are beginning to be widely used for the treatment of a variety of diseases. During the present project period we adopted LTBMC systems developed by others for the purposes of our specific aims. Also we developed a novel long term culture system for NK cells. The discovery of a new growth factor, O-CSF, specific for osteoclasts and the establishment of a clonal assay system that provides evidence for a new class of hemopoietic progenitor cells, the osteoclast progenitor, are important contributions. Given the important role T cells play in the immune response and in the regulation of other lymphohemopoietic cell lineages through the lymphokines they secrete, the need for an in vitro system that lends itself to the analysis of T cell maturation and to the testing of factors that may adversely affect T lymphopoiesis cannot be overemphasized. We believe that we can exploit an advantageous set of circumstances that present an excellent opportunity for initiating a focused experimental program for developing such a system. By a systematic and selective analysis of molecular interactions between heterogenous thymic stromal cells and T cell progenitors at different stages of maturation, it will be possible for our program to define the complement of critical cellular interactions on which successive stages of T lymphopoiesis depend. The experiments we propose will lay a rational foundation for the development of a long term culture system for T lymphopoiesis. 24 refs., 7 figs.

  19. Visualizing Antibody Affinity Maturation in Germinal Centers

    PubMed Central

    Tas, Jeroen M.J.; Mesin, Luka; Pasqual, Giulia; Targ, Sasha; Jacobsen, Johanne T.; Mano, Yasuko M.; Chen, Casie S.; Weill, Jean-Claude; Reynaud, Claude-Agnès; Browne, Edward P.; Meyer-Hermann, Michael; Victora, Gabriel D.

    2016-01-01

    Antibodies somatically mutate to attain high affinity in germinal centers (GCs). There, competition between B cell clones and among somatic mutants of each clone drives an increase in average affinity across the population. The extent to which higher-affinity cells eliminating competitors restricts clonal diversity is unknown. By combining multiphoton microscopy and sequencing, we show that tens to hundreds of distinct B cell clones seed each GC, and that GCs lose clonal diversity at widely disparate rates. Furthermore, efficient affinity maturation can occur in the absence of homogenizing selection, ensuring that many clones can mature in parallel within the same GC. Our findings have implications for development of vaccines in which antibodies with non-immunodominant specificities must be elicited, as is the case for HIV-1 and influenza. PMID:26912368

  20. Remotely sensing wheat maturation with radar

    NASA Technical Reports Server (NTRS)

    Bush, T. F.; Ulaby, F. T.

    1975-01-01

    The scattering properties of wheat were studied in the 8-18 GHz band as a function of frequency, polarization, incidence angle, and crop maturity. Supporting ground truth was collected at the time of measurement. The data indicate that the radar backscattering coefficient is sensitive to both radar system parameters and crop characteristics particularly at incidence angles near nadir. Linear regression analyses of the radar backscattering coefficient on both time and plant moisture content result in rather good correlation. Furthermore, by calculating the average time rate of change of the radar backscattering coefficient it is found that it undergoes rapid variations shortly before and after the wheat is harvested. Both of these analyses suggest methods for estimating wheat maturity and for monitoring the progress of harvest.

  1. Predicting skeletal maturation using cervical vertebrae.

    PubMed

    Minars, Michael; Burch, James; Masella, Richard; Meister, Malcolm

    2003-10-01

    This study's objective was to familiarize the profession with determining skeletal maturation and skeletal age, and predicting growth potential by using cervical vertebrae images of lateral cephalograms. The investigation was done through repeated evaluations of 30 randomly selected, pretreatment lateral cepaholometric radiographs. The accuracy of determining skeletal age and growth potential with lateral cephalograms was found to be R=0.98 (highly accurate) by statistical analysis.

  2. Maturation of Fetal Responses to Music

    ERIC Educational Resources Information Center

    Kisilevsky, B. S.; Hains, S. M. J.; Jacquet, A.-Y.; Granier-Deferre, C.; Lecanuet, J. P.

    2004-01-01

    Maturation of fetal response to music was characterized over the last trimester of pregnancy using a 5-minute piano recording of Brahms' Lullaby, played at an average of 95, 100, 105 or 110 dB (A). Within 30 seconds of the onset of the music, the youngest fetuses (28-32 weeks GA) showed a heart rate increase limited to the two highest dB levels;…

  3. Mature brain tissue in the sacrococcygeal region

    PubMed Central

    Shrestha, Binod Bade; Ghimire, Pradeep; Ghartimagar, Dilasma; Jwarchan, Bishnu; Lalchan, Subita; Karmacharya, Mikesh

    2016-01-01

    Complete mature brain tissue in sacrococcygeal region is a rare congenital anomaly in a newborn, which usually is misdiagnosed for sacrococcygeal teratoma. Glial tumor-like ependymoma is also common in sacrococcygeal area but mostly appears later in life. We present a case of complete heterotopic brain tissue in the sacrococcygeal region. The patient underwent total excision of mass with coccygectomy. To our knowledge it is the second case being reported. PMID:27194682

  4. NATO NEC C2 Maturity Model

    DTIC Science & Technology

    2010-02-01

    This broader construct demands greater agility on the part of both military and non-military leadership and organisations. Therefore, agility must be...the situation; • infrastructure (availability, quality); • clarity, unity of intent (purpose), and strategy ; • nature of effects space (PMESII...in time, energy , and resources needed for higher levels of C2 maturity is clear from the analysis in these experiences. From the perspective of the

  5. Mature monocytic cells enter tissues and engraft

    PubMed Central

    Kennedy, David W.; Abkowitz, Janis L.

    1998-01-01

    The goal of this study was to identify the circulating cell that is the immediate precursor of tissue macrophages. ROSA 26 marrow mononuclear cells (containing the β-geo transgene that encodes β-galactosidase and neomycin resistance activities) were cultured in the presence of macrophage colony-stimulating factor and flt3 Ligand for 6 days to generate monocytic cells at all stages of maturation. Expanded monocyte cells (EMC), the immature (ER-MP12+) and more mature (ER-MP20+) subpopulations, were transplanted into irradiated B6/129 F2 mice. β-gal staining of tissue sections from animals 15 min after transplantation demonstrated that the donor cells landed randomly. By 3 h, donor cells in lung and liver were more frequent in animals transplanted with ER-MP20+ (more mature) EMC than in animals transplanted with unseparated EMC or fresh marrow mononuclear cells, a pattern that persisted at 3 and 7 days. At 3 days, donor cells were found in spleen, liver, lung, and brain (rarely) as clusters as well as individual cells. By 7 and 14 days, the clusters had increased in size, and the cells expressed the macrophage antigen F4/80, suggesting that further replication and differentiation had occurred. PCR for the neogene was used to quantitate the amount of donor DNA in tissues from transplanted animals and confirmed that ER-MP20+ EMC preferentially engrafted. These data demonstrate that a mature monocytic cell gives rise to tissue macrophages. Because these cells can be expanded and manipulated in vitro, they may be a suitable target population for gene therapy of lysosomal storage diseases. PMID:9843995

  6. DNA damage response during mouse oocyte maturation

    PubMed Central

    Mayer, Alexandra; Baran, Vladimir; Sakakibara, Yogo; Brzakova, Adela; Ferencova, Ivana; Motlik, Jan; Kitajima, Tomoya S.; Schultz, Richard M.; Solc, Petr

    2016-01-01

    ABSTRACT Because low levels of DNA double strand breaks (DSBs) appear not to activate the ATM-mediated prophase I checkpoint in full-grown oocytes, there may exist mechanisms to protect chromosome integrity during meiotic maturation. Using live imaging we demonstrate that low levels of DSBs induced by the radiomimetic drug Neocarzinostatin (NCS) increase the incidence of chromosome fragments and lagging chromosomes but do not lead to APC/C activation and anaphase onset delay. The number of DSBs, represented by γH2AX foci, significantly decreases between prophase I and metaphase II in both control and NCS-treated oocytes. Transient treatment with NCS increases >2-fold the number of DSBs in prophase I oocytes, but less than 30% of these oocytes enter anaphase with segregation errors. MRE11, but not ATM, is essential to detect DSBs in prophase I and is involved in H2AX phosphorylation during metaphase I. Inhibiting MRE11 by mirin during meiotic maturation results in anaphase bridges and also increases the number of γH2AX foci in metaphase II.  Compromised DNA integrity in mirin-treated oocytes indicates a role for MRE11 in chromosome integrity during meiotic maturation. PMID:26745237

  7. Maturation modeling in Otway Basin, Australia

    SciTech Connect

    Middleton, M.F.; Falvey, D.A.

    1983-02-01

    The Otway basin is a Jurassic to Pliocene sedimentary basin formed on the southern Australian continental margin. Its formation is associated with rifting and breakup of the Australian and Antarctic plates. Lithospheric cooling and contraction have probably produced post-breakup subsidence. Either lithospheric stretching or deep crustal metamorphism may have produced pre-breakup subsidence. These mechanisms have identifiable thermal histories. Organic diagenesis (specifically the reflectance of vitrinite in oil) is empirically determined by the thermal and depositional history of an organic sediment. Thus, the stages of hydrocarbon maturity of Otway basin sediments can be modeled. Depositional history is determined from ''geohistory analysis'' and thermal history depends on the subsidence mechanism applied to the basin. A paleo-heat-flow history derived from the deep crustal metamorphism model of subsidence produces a maturation profile with depth that is consistent with observed vitrinite reflectance data, although organic diagenesis modeling is relatively insensitive to precise details of thermal history. Depositional and maturation history modeling for the present day, 20 Ma ago, 40 Ma ago, and 60 Ma ago is applied to a seismic profile across the southern Australian continental shelf in the Otway basin as a demonstration of the projection backward in time of sedimentation and organic diagenesis.

  8. Proteolysis regulates cardiomyocyte maturation and tissue integration

    PubMed Central

    Fukuda, Ryuichi; Gunawan, Felix; Beisaw, Arica; Jimenez-Amilburu, Vanesa; Maischein, Hans-Martin; Kostin, Sawa; Kawakami, Koichi; Stainier, Didier Y. R.

    2017-01-01

    Tissue integrity is critical for organ formation and function. During heart development, cardiomyocytes differentiate and integrate to form a coherent tissue that contracts synchronously. However, the molecular mechanisms regulating cardiac tissue integrity are poorly understood. Here we show that proteolysis, via the E3 ubiquitin ligase ASB2, regulates cardiomyocyte maturation and tissue integrity. Cardiomyocytes in asb2b zebrafish mutants fail to terminally differentiate, resulting in reduced cardiac contractility and output. Mosaic analyses reveal a cell-autonomous requirement for Asb2b in cardiomyocytes for their integration as asb2b mutant cardiomyocytes are unable to meld into wild-type myocardial tissue. In vitro and in vivo data indicate that ASB2 negatively regulates TCF3, a bHLH transcription factor. TCF3 must be degraded for cardiomyocyte maturation, as TCF3 gain-of-function causes a number of phenotypes associated with cardiomyocyte dedifferentiation. Overall, our results show that proteolysis has an important role in cardiomyocyte maturation and the formation of a coherent myocardial tissue. PMID:28211472

  9. The AGU Data Management Maturity Model Initiative

    NASA Astrophysics Data System (ADS)

    Bates, J. J.

    2015-12-01

    In September 2014, the AGU Board of Directors approved two initiatives to help the Earth and space sciences community address the growing challenges accompanying the increasing size and complexity of data. These initiatives are: 1) Data Science Credentialing: development of a continuing education and professional certification program to help scientists in their careers and to meet growing responsibilities and requirements around data science; and 2) Data Management Maturity (DMM) Model: development and implementation of a data management maturity model to assess process maturity against best practices, and to identify opportunities in organizational data management processes. Each of these has been organized within AGU as an Editorial Board and both Boards have held kick off meetings. The DMM model Editorial Board will recommend strategies for adapting and deploying a DMM model to the Earth and space sciences create guidance documents to assist in its implementation, and provide input on a pilot appraisal process. This presentation will provide an overview of progress to date in the DMM model Editorial Board and plans for work to be done over the upcoming year.

  10. Epigenetic mechanisms in pubertal brain maturation

    PubMed Central

    Morrison, Kathleen E.; Rodgers, Ali B.; Morgan, Christopher P.; Bale, Tracy L.

    2014-01-01

    Puberty is a critical period of development during which the reemergence of gonadotropin releasing hormone secretion from the hypothalamus triggers a cascade of hormone-dependent processes. Maturation of specific brain regions including the prefrontal cortex occurs during this window, but the complex mechanisms underlying these dynamic changes are not well understood. Particularly, the potential involvement of epigenetics in this programming has been under-examined. The epigenome is known to guide earlier stages of development, and it is similarly poised to regulate vital pubertal-driven brain maturation. Further, as epigenetic machinery is highly environmentally responsive, its involvement may also lend this period of growth to greater vulnerability to external insults, resulting in reprogramming and increased disease risk. Importantly, neuropsychiatric diseases commonly present in individuals during or immediately following puberty, and environmental perturbations including stress may precipitate disease onset by disrupting the normal trajectory of pubertal brain development via epigenetic mechanisms. In this review, we discuss epigenetic processes involved in pubertal brain maturation, the potential points of derailment, and the importance of future studies for understanding this dynamic developmental window and gaining a better understanding of neuropsychiatric disease risk. PMID:24239720

  11. The Mature Athlete’s Shoulder

    PubMed Central

    Tokish, John M.

    2014-01-01

    Context: The mature athlete’s shoulder remains a challenging clinical condition to manage. A normal natural history of the shoulder includes stiffness, rotator cuff tears, and osteoarthritis, all of which can become increasingly more symptomatic as an athlete ages. Evidence Acquisition: PubMed (1978-2013). Study Design: Clinical review. Level of Evidence: Level 3-4. Results: Rotator cuff pathology increases with age and activity level. Partial tears rarely heal, and debridement of significant partial tears results in poorer outcomes than those of repair. Repair of partial-thickness tears can be accomplished with completion and subsequent repair or in situ repair. The most successful result for treatment of osteoarthritis in the shoulder remains total shoulder arthroplasty, with more than 80% survival at 20 years and high rates of return to sport. Caution should be taken in patients younger than 60 years, as they show much worse results with this treatment. Adhesive capsulitis of the shoulder can be successfully treated with nonoperative management in 90% of cases. Conclusion: Mature athletes tend to have rotator cuff pathology, osteoarthritis, and stiffness, which may limit their participation in athletic events. Age is a significant consideration, even within the “mature athlete” population, as patients younger than 50 years should be approached differently than those older than 65 years with regard to treatment regimens and postoperative restriction. PMID:24427439

  12. Technology Maturation of Integrated System Health Management

    NASA Astrophysics Data System (ADS)

    Feather, Martin S.; Uckun, Serdar; Hicks, Kenneth A.

    2008-01-01

    Despite two decades of significant investments in R&D of Integrated System Health Management (ISHM), mission-critical applications of it in aerospace are few and far between. ISHM is subject to the general difficulty of transitioning technologies out of R&D labs and into practical applications. New and unproven methods such as ISHM introduce multiple mission risks (technology, schedule, cost), and may require a transition to unconventional and as-yet-unproven operations concepts in order to be effective. Laboratory and flight demonstrations are necessary but insufficient to adequately reduce those risks. What is needed is a solid business case before a new technology can be considered for fleetwide deployment. To address these problems, we recently applied a technology maturation assessment process developed at NASA's Jet Propulsion Laboratory to study the challenges of ISHM technology maturation. This application resulted in identification of the technologies (and technology maturation activities) that would result in the greatest risk reduction per investment dollar. Our approach and its results are described herein.

  13. Early Versus Late Maturation Arrest: Reproductive Outcomes of Testicular Failure

    PubMed Central

    Weedin, John W.; Bennett, Richard C.; Fenig, David M.; Lamb, Dolores J.; Lipshultz, Larry I.

    2013-01-01

    Purpose There is a paucity of data characterizing infertile men with maturation arrest. We hypothesized that men with early stage maturation arrest could be clinically distinguished from men with late maturation arrest and would have worse reproductive outcomes. Materials and Methods We retrospectively reviewed the records of all patients with nonobstructive azoospermia and cryptozoospermia who underwent testis mapping and sperm extraction from 2002 to 2009 and for whom histopathological findings were available. Patients had uniform maturation arrest if multiple biopsies revealed maturation arrest at the spermatogonia/spermatocyte (early maturation arrest) or the spermatid (late maturation arrest) stage. Clinical parameters and pregnancy outcomes of in vitro fertilization/intracytoplasmic sperm injection were examined. Statistical analysis consisted of univariate and multivariate analysis. Results Uniform maturation arrest was identified in 49 of 219 men (22.3%) undergoing testicular sperm extraction. On multivariate analysis men with maturation arrest had significantly larger testes (p = 0.01), decreased follicle-stimulating hormone (p = 0.05) and more detectable genetic abnormalities (p = 0.01) than men with other histopathological conditions. Men with late maturation arrest had decreased follicle-stimulating hormone (p = 0.02), increased testosterone (p = 0.03) and a higher sperm retrieval rate at testicular sperm extraction (p = 0.01) than men with early maturation arrest. Predictors of successful sperm retrieval were larger testes, cryptozoospermia, late maturation arrest and hypospermatogenesis (each p ≤0.05). Pregnancy outcomes for men with maturation arrest were not significantly different from those for men with other histopathological conditions. Conclusions Maturation arrest is a common, diverse histopathological subtype of severe male infertility. Compared to men with late maturation arrest those with early maturation arrest have increased follicle

  14. Lower esophageal sphincter relaxation reflex kinetics: effects of peristaltic reflexes and maturation in human premature neonates.

    PubMed

    Pena, Eneysis M; Parks, Vanessa N; Peng, Juan; Fernandez, Soledad A; Di Lorenzo, Carlo; Shaker, Reza; Jadcherla, Sudarshan R

    2010-12-01

    We defined the sensory-motor characteristics of the lower esophageal sphincter relaxation (LESR) (stimulus threshold volume, response onset, and relaxation period, relaxation magnitude, nadir) during maturation in human neonates. We hypothesized that LESR kinetics differs during maturation and with peristaltic reflex type. Basal and adaptive esophageal motility testing was performed (N = 20 premature neonates) at 34.7 and 39.1 wk (time 1 and time 2). Effects of midesophageal provocation with graded stimuli (N = 1,267 stimuli, air and liquids) on LESR kinetics during esophagodeglutition response (EDR) and secondary peristalsis (SP) were analyzed by mixed models. Frequency of LESR with basal primary peristalsis were different during maturation (P = 0.03). During adaptive responses with maturation, 1) the frequencies of peristaltic reflexes and LESR were similar; 2) liquid stimuli resulted in a shorter LESR response latency and LESR nadir and greater LESR magnitude (all P < 0.05); 3) media differences were noted with LESR response latency (air vs. liquids, P < 0.02); and 4) infusion flow rate-LESR were different (P < 0.01 for air and liquids). Mechanistically, 1) frequency of LESR was greater during peristaltic reflexes at both times (vs. none, P < 0.0001); 2) LESR response latency, duration, and time to complete LESR were longer with EDR (all P < 0.05, vs. SP at time 2); and 3) graded stimulus volume LESR were different for air and liquids (P < 0.01). In conclusion, sensory-motor characteristics of LESR depend on the mechanosensitive properties of the stimulus (media, volume, flow), type of peristaltic reflex, and postnatal maturation. Maturation modulates an increased recruitment of inhibitory pathways that favor LESR.

  15. Firefighting Module

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Firefly II pump module is NASA's Marshall Space Flight Center's commercial offshoot of a NASA/US Coast Guard program involving development of a lightweight, helicopter-transportable firefighting module for a quick response in combating shipboard or harbor fires. Operable on land or water, the Amphib One is equipped with 3 water cannons. When all 3 are operating, unit pumps more than 3,000 gallons a minute. Newly developed model used by U.S. Coast Guard can pump 5,000 gallons per minute. It was designed for applications such as firefighting onboard ship fires, emergency dockside water pumping, dewatering ships in danger of sinking, flood control, and emergency water supply at remote locations.

  16. Thermoelectric module

    DOEpatents

    Kortier, William E.; Mueller, John J.; Eggers, Philip E.

    1980-07-08

    A thermoelectric module containing lead telluride as the thermoelectric mrial is encapsulated as tightly as possible in a stainless steel canister to provide minimum void volume in the canister. The lead telluride thermoelectric elements are pressure-contacted to a tungsten hot strap and metallurgically bonded at the cold junction to iron shoes with a barrier layer of tin telluride between the iron shoe and the p-type lead telluride element.

  17. 7 CFR 51.1555 - Fairly well matured.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ....1555 Fairly well matured. Fairly well matured means that the skins of the potatoes are generally fairly firmly set and not more than 10 percent of the potatoes in the lot have more than one-fourth of the...

  18. 7 CFR 51.1555 - Fairly well matured.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ....1555 Fairly well matured. Fairly well matured means that the skins of the potatoes are generally fairly firmly set and not more than 10 percent of the potatoes in the lot have more than one-fourth of the...

  19. Moral Judgment Maturity of Process and Reactive Schizophrenics.

    ERIC Educational Resources Information Center

    Herron, William G.; And Others

    1983-01-01

    Premorbid adjustment, paranoid symptomatology, and orientation were examined as major predictors of moral judgment maturity in 40 schizophrenics. Results suggest the importance of cognitive and social skills in the development of schizophrenics' moral judgment maturity. (Author/RH)

  20. Linear modulator

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A study of frequency division multiplexing (FDM) systems was made for the purpose of determining the system performance that can be obtained with available state of the art components. System performance was evaluated on the basis of past experience, system analysis, and component evaluation. The system study was specifically directed to the area of FDM systems using subcarrier channel frequencies from 4 kHz to 200 kHz and channel information bandwidths of dc to 1, 2, 4, 8, and 16 kHz. The evaluation also assumes that the demodulation will be from a tape recorder which produces frequency modulation of + or - 1% on the signal due to the tape recorder wow and flutter. For the modulation system it is assumed that the pilot and carrier channel frequencies are stable to within + or - .005% and that the FM on the channel carriers is negligible. The modulator system was evaluated for the temperature range of -20 degree to +85 degree while the demodulator system was evaluated for operation at room temperature.

  1. The LGI1-ADAM22 protein complex directs synapse maturation through regulation of PSD-95 function.

    PubMed

    Lovero, Kathryn L; Fukata, Yuko; Granger, Adam J; Fukata, Masaki; Nicoll, Roger A

    2015-07-28

    Synapse development is coordinated by a number of transmembrane and secreted proteins that come together to form synaptic organizing complexes. Whereas a variety of synaptogenic proteins have been characterized, much less is understood about the molecular networks that support the maintenance and functional maturation of nascent synapses. Here, we demonstrate that leucine-rich, glioma-inactivated protein 1 (LGI1), a secreted protein previously shown to modulate synaptic AMPA receptors, is a paracrine signal released from pre- and postsynaptic neurons that acts specifically through a disintegrin and metalloproteinase protein 22 (ADAM22) to set postsynaptic strength. We go on to describe a novel role for ADAM22 in maintaining excitatory synapses through PSD-95/Dlg1/zo-1 (PDZ) domain interactions. Finally, we show that in the absence of LGI1, the mature synapse scaffolding protein PSD-95, but not the immature synapse scaffolding protein SAP102, is unable to modulate synaptic transmission. These results indicate that LGI1 and ADAM22 form an essential synaptic organizing complex that coordinates the maturation of excitatory synapses by regulating the functional incorporation of PSD-95.

  2. Human dendritic cell maturation and cytokine secretion upon stimulation with Bordetella pertussis filamentous haemagglutinin.

    PubMed

    Dirix, Violette; Mielcarek, Nathalie; Debrie, Anne-Sophie; Willery, Eve; Alonso, Sylvie; Versheure, Virginie; Mascart, Françoise; Locht, Camille

    2014-07-01

    In addition to antibodies, Th1-type T cell responses are also important for long-lasting protection against pertussis. However, upon immunization with the current acellular vaccines, many children fail to induce Th1-type responses, potentially due to immunomodulatory effects of some vaccine antigens, such as filamentous haemagglutinin (FHA). We therefore analysed the ability of FHA to modulate immune functions of human monocyte-derived dendritic cells (MDDC). FHA was purified from pertussis toxin (PTX)-deficient or from PTX- and adenylate cyclase-deficient Bordetella pertussis strains, and residual endotoxin was neutralized with polymyxin B. FHA from both strains induced phenotypic maturation of human MDDC and cytokine secretion (IL-10, IL-12p40, IL-12p70, IL-23 and IL-6). To identify the FHA domains responsible for MDDC immunomodulation, MDDC were stimulated with FHA containing a Gly→Ala substitution at its RGD site (FHA-RAD) or with an 80-kDa N-terminal moiety of FHA (Fha44), containing its heparin-binding site. Whereas FHA-RAD induced maturation and cytokine production comparable to those of FHA, Fha44 did not induce IL-10 production, but maturated MDDC at least partially. Nevertheless, Fha44 induced the secretion of IL-12p40, IL-12p70, IL-23 and IL-6 by MDDC, albeit at lower levels than FHA. Thus, FHA can modulate MDDC responses in multiple ways, and IL-10 induction can be dissociated from the induction of other cytokines.

  3. Hormone-induced cortical maturation ensures the slow block to polyspermy and does not couple with meiotic maturation in starfish.

    PubMed

    Hirohashi, Noritaka; Harada, Kaori; Chiba, Kazuyoshi

    2008-06-01

    Meiotic progression in starfish oocytes is reinitiated by a maturation-inducing hormone called 1-methyladenine (1-MeAde). In addition to meiotic maturation, 1-MeAde induces cortical maturation in which cortical granules become competent to discharge in response to fusion of a single sperm, which results in the formation of the fertilization envelope. We found that subthreshold concentrations of 1-MeAde induce cortical maturation without germinal vesicle breakdown (GVBD). During cortical maturation, the IP3 sensitivity of calcium stores was increased as well as during meiotic maturation. When oocytes were exposed with 1-MeAde only on a hemisphere of oocytes, the IP3 sensitivity of the cortical region was increased only in the exposed hemisphere, suggesting that signals and components involved in cortical maturation do not readily spread in the cytoplasm. Although a specific inhibitor of phosphatidylinositol-3 kinase, LY294002 blocked both GVBD and cortical maturation, a Cdc2 kinase inhibitor, roscovitine did not block cortical maturation. Inhibition of Akt activation by injecting the competitors for Akt phosphorylation and membrane recruitment also blocked cortical maturation. These results suggest that the signaling pathway leading to Akt activation is common in cortical maturation and meiotic maturation, and Cdc2 activation was not required for cortical maturation.

  4. How to Be a Better Consumer of Security Maturity Models

    DTIC Science & Technology

    2014-10-21

    cybersecurity and resilience domains • Be aware of caution flags when dealing with maturity models • Determine how to choose the right model for your... cybersecurity program? Maturity Models Member Query 17 Maturity Models Member Query – Q1 Have you or your organization ever used any type of maturity...networked systems CERT – Anticipating and solving our nation’s cybersecurity challenges • Largest technical program at SEI • Focused on internet

  5. Everything You Always Wanted to Know About Maturity Models

    DTIC Science & Technology

    2014-01-23

    Types of Maturity Models • Examples of Maturity Models 11 © 2014 Carnegie Mellon University Maturity Model Defined An organized way to convey a...path of experience, wisdom, perfection, or acculturation . Depicts an evolutionary progression of an attribute, characteristic, pattern, or...practice. The subject of a maturity model can be objects or things, ways of doing something, characteristics of something, practices, controls, or

  6. Engineering adolescence: maturation of human pluripotent stem cell-derived cardiomyocytes.

    PubMed

    Yang, Xiulan; Pabon, Lil; Murry, Charles E

    2014-01-31

    The discovery of human pluripotent stem cells (hPSCs), including both human embryonic stem cells and human-induced pluripotent stem cells, has opened up novel paths for a wide range of scientific studies. The capability to direct the differentiation of hPSCs into functional cardiomyocytes has provided a platform for regenerative medicine, development, tissue engineering, disease modeling, and drug toxicity testing. Despite exciting progress, achieving the optimal benefits has been hampered by the immature nature of these cardiomyocytes. Cardiac maturation has long been studied in vivo using animal models; however, finding ways to mature hPSC cardiomyocytes is only in its initial stages. In this review, we discuss progress in promoting the maturation of the hPSC cardiomyocytes, in the context of our current knowledge of developmental cardiac maturation and in relation to in vitro model systems such as rodent ventricular myocytes. Promising approaches that have begun to be examined in hPSC cardiomyocytes include long-term culturing, 3-dimensional tissue engineering, mechanical loading, electric stimulation, modulation of substrate stiffness, and treatment with neurohormonal factors. Future studies will benefit from the combinatorial use of different approaches that more closely mimic nature's diverse cues, which may result in broader changes in structure, function, and therapeutic applicability.

  7. Effects of sex pheromones and sexual maturation on locomotor activity in female sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Walaszczyk, Erin J.; Johnson, Nicholas S.; Steibel, Juan Pedro; Li, Weiming

    2013-01-01

    Synchronization of male and female locomotor rhythmicity can play a vital role in ensuring reproductive success. Several physiological and environmental factors alter these locomotor rhythms. As sea lamprey, Petromyzon marinus, progress through their life cycle, their locomotor activity rhythm changes multiple times. The goal of this study was to elucidate the activity patterns of adult female sea lamprey during the sexual maturation process and discern the interactions of these patterns with exposure to male pheromones. During these stages, preovulated and ovulated adult females are exposed to sex pheromone compounds, which are released by spermiated males and attract ovulated females to the nest for spawning. The locomotor behavior of adult females was monitored in a natural stream with a passive integrated tag responder system as they matured, and they were exposed to a sex pheromone treatment (spermiated male washings) or a control (prespermiated male washings). Results showed that, dependent on the hour of day, male sex pheromone compounds reduce total activity (p < 0.05) and cause increases in activity during several daytime hours in preovulated and ovulated females. These results are one of the first examples of how sex pheromones modulate a locomotor rhythm in a vertebrate, and they suggest that the interaction between maturity stage and sex pheromone exposure contributes to the differential locomotor rhythms found in adult female sea lamprey. This phenomenon may contribute to the reproductive synchrony of mature adults, thus increasing reproductive success in this species.

  8. Importin 8 regulates the transport of mature microRNAs into the cell nucleus.

    PubMed

    Wei, Yao; Li, Limin; Wang, Dong; Zhang, Chen-Yu; Zen, Ke

    2014-04-11

    Mature microRNAs (miRNAs), ∼ 22-nucleotide noncoding RNAs regulating target gene expression at the post-transcriptional level, have been recently shown to be transported into the nucleus where they modulate the biogenesis of other miRNAs or their own expression. However, the mechanism that governs the transport of mature miRNAs from cytoplasm to nucleus remains unknown. Here, we report that importin 8 (IPO8), a member of the karyopherin β (also named the protein import receptor importin β) family, plays a critical role in mediating the cytoplasm-to-nucleus transport of mature miRNAs. Specifically knocking down IPO8 but not other karyopherin β family proteins via siRNA significantly decreases the nuclear transport of various known nucleus-enriched miRNAs without affecting their total cellular levels. IPO8-mediated nuclear transport of mature miRNAs is also dependent on the association of IPO8 with the Argonaute 2 (Ago2) complex. Cross-immunoprecipitation and Western blot analysis show that IPO8 is physically associated with Ago2. Knocking down IPO8 via siRNA markedly decreases the nuclear transport of Ago2 but does not affect the total cellular Ago2 level. Furthermore, dissociating the binding of miRNAs with Ago2 by trypaflavine strongly reduces the IPO8-mediated nuclear transport of miRNAs.

  9. Gene Expression Profiling of the Cephalothorax and Eyestalk in Penaeus Monodon during Ovarian Maturation

    PubMed Central

    Brady, Philip; Elizur, Abigail; Williams, Richard; Cummins, Scott F.; Knibb, Wayne

    2012-01-01

    In crustaceans, a range of physiological processes involved in ovarian maturation occurs in organs of the cephalothorax including the hepatopancrease, mandibular and Y-organ. Additionally, reproduction is regulated by neuropeptide hormones and other proteins released from secretory sites within the eyestalk. Reproductive dysfunction in captive-reared prawns, Penaeus monodon, is believed to be due to deficiencies in these factors. In this study, we investigated the expression of gene transcripts in the cephalothorax and eyestalk from wild-caught and captive-reared animals throughout ovarian maturation using custom oligonucleotide microarray screening. We have isolated numerous transcripts that appear to be differentially expressed throughout ovarian maturation and between wild-caught and captive-reared animals. In the cephalothorax, differentially expressed genes included the 1,3-β-D-glucan-binding high-density lipoprotein, 2/3-oxoacyl-CoA thiolase and vitellogenin. In the eyestalk, these include gene transcripts that encode a protein that modulates G-protein coupled receptor activity and another that encodes an architectural transcription factor. Each may regulate the expression of reproductive neuropeptides, such as the crustacean hyperglycaemic hormone and molt-inhibiting hormone. We could not identify differentially expressed transcripts encoding known reproductive neuropeptides in the eyestalk of either wild-caught or captive-reared prawns at any ovarian maturation stage, however, this result may be attributed to low relative expression levels of these transcripts. In summary, this study provides a foundation for the study of target genes involved in regulating penaeid reproduction. PMID:22355268

  10. Drug information systems: evolution of benefits with system maturity.

    PubMed

    Leung, Valerie; Hagens, Simon; Zelmer, Jennifer

    2013-01-01

    Benefits from information and communication technology tend to grow over time as system use matures. This study examines pharmacists' experiences with provincial drug information systems (DIS) across Canada. At the time of survey, two provinces had more mature DIS (more than five years) and three provinces had less mature DIS (five years or less).

  11. 7 CFR 1427.174 - Maturity of seed cotton loans.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 10 2013-01-01 2013-01-01 false Maturity of seed cotton loans. 1427.174 Section 1427..., DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Recourse Seed Cotton Loans § 1427.174 Maturity of seed cotton loans. Seed cotton loans mature on demand by CCC but no later than May 31...

  12. 7 CFR 1427.174 - Maturity of seed cotton loans.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Maturity of seed cotton loans. 1427.174 Section 1427..., DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Recourse Seed Cotton Loans § 1427.174 Maturity of seed cotton loans. Seed cotton loans mature on demand by CCC but no later than May 31...

  13. 7 CFR 1427.174 - Maturity of seed cotton loans.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Maturity of seed cotton loans. 1427.174 Section 1427..., DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Recourse Seed Cotton Loans § 1427.174 Maturity of seed cotton loans. Seed cotton loans mature on demand by CCC but no later than May 31...

  14. 7 CFR 1427.174 - Maturity of seed cotton loans.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Maturity of seed cotton loans. 1427.174 Section 1427..., DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Recourse Seed Cotton Loans § 1427.174 Maturity of seed cotton loans. Seed cotton loans mature on demand by CCC but no later than May 31...

  15. 7 CFR 1427.174 - Maturity of seed cotton loans.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Maturity of seed cotton loans. 1427.174 Section 1427..., DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Recourse Seed Cotton Loans § 1427.174 Maturity of seed cotton loans. Seed cotton loans mature on demand by CCC but no later than May 31...

  16. The Relationship between Attitudinal and Behavioral Aspects of Career Maturity.

    ERIC Educational Resources Information Center

    Fouad, Nadya A.; Keeley, Timothy J.

    1992-01-01

    Investigated whether a meaningful relationship existed between an attitudinal measure of career maturity and a measure of career maturity reflecting job performance-related behavioral competencies in African-American high school students (n=74). Only modest relationships were found between several career maturity attitudes and behavioral measures.…

  17. Sex Differences in a Causal Model of Career Maturity.

    ERIC Educational Resources Information Center

    King, Suzanne

    1989-01-01

    Studied sex differences among high school students (N=318) in career development process to determine whether sex differences exist in way six independent variables interact in career maturity causal model of career maturity and to compare each variable's effect on career maturity. Results suggest significant sex differences consistent with…

  18. Career Maturity of Emotionally Maladjusted High School Students.

    ERIC Educational Resources Information Center

    Karayanni, Mousa

    1981-01-01

    The Career Maturity Inventory Scale was used to investigate the vocational maturity of emotionally maladjusted and well-adjusted high school students. Results indicated a significant difference in career maturity between the two groups. Sex, class, and race differences were also examined. (RC)

  19. CX3CR1-dependent recruitment of mature NK cells into the central nervous system contributes to control autoimmune neuroinflammation.

    PubMed

    Hertwig, Laura; Hamann, Isabell; Romero-Suarez, Silvina; Millward, Jason M; Pietrek, Rebekka; Chanvillard, Coralie; Stuis, Hanna; Pollok, Karolin; Ransohoff, Richard M; Cardona, Astrid E; Infante-Duarte, Carmen

    2016-08-01

    Fractalkine receptor (CX3CR1)-deficient mice develop very severe experimental autoimmune encephalomyelitis (EAE), associated with impaired NK cell recruitment into the CNS. Yet, the precise implications of NK cells in autoimmune neuroinflammation remain elusive. Here, we investigated the pattern of NK cell mobilization and the contribution of CX3CR1 to NK cell dynamics in the EAE. We show that in both wild-type and CX3CR1-deficient EAE mice, NK cells are mobilized from the periphery and accumulate in the inflamed CNS. However, in CX3CR1-deficient mice, the infiltrated NK cells displayed an immature phenotype contrasting with the mature infiltrates in WT mice. This shift in the immature/mature CNS ratio contributes to EAE exacerbation in CX3CR1-deficient mice, since transfer of mature WT NK cells prior to immunization exerted a protective effect and normalized the CNS NK cell ratio. Moreover, mature CD11b(+) NK cells show higher degranulation in the presence of autoreactive 2D2 transgenic CD4(+) T cells and kill these autoreactive cells more efficiently than the immature CD11b(-) fraction. Together, these data suggest a protective role of mature NK cells in EAE, possibly through direct modulation of T cells inside the CNS, and demonstrate that mature and immature NK cells are recruited into the CNS by distinct chemotactic signals.

  20. Photovoltaic module and module arrays

    DOEpatents

    Botkin, Jonathan [El Cerrito, CA; Graves, Simon [Berkeley, CA; Lenox, Carl J. S. [Oakland, CA; Culligan, Matthew [Berkeley, CA; Danning, Matt [Oakland, CA

    2012-07-17

    A photovoltaic (PV) module including a PV device and a frame. The PV device has a PV laminate defining a perimeter and a major plane. The frame is assembled to and encases the laminate perimeter, and includes leading, trailing, and side frame members, and an arm that forms a support face opposite the laminate. The support face is adapted for placement against a horizontal installation surface, to support and orient the laminate in a non-parallel or tilted arrangement. Upon final assembly, the laminate and the frame combine to define a unitary structure. The frame can orient the laminate at an angle in the range of 3.degree.-7.degree. from horizontal, and can be entirely formed of a polymeric material. Optionally, the arm incorporates integral feature(s) that facilitate interconnection with corresponding features of a second, identically formed PV module.

  1. Photovoltaic module and module arrays

    DOEpatents

    Botkin, Jonathan; Graves, Simon; Lenox, Carl J. S.; Culligan, Matthew; Danning, Matt

    2013-08-27

    A photovoltaic (PV) module including a PV device and a frame, The PV device has a PV laminate defining a perimeter and a major plane. The frame is assembled to and encases the laminate perimeter, and includes leading, trailing, and side frame members, and an arm that forms a support face opposite the laminate. The support face is adapted for placement against a horizontal installation surface, to support and orient the laminate in a non-parallel or tilted arrangement. Upon final assembly, the laminate and the frame combine to define a unitary structure. The frame can orient the laminate at an angle in the range of 3.degree.-7.degree. from horizontal, and can be entirely formed of a polymeric material. Optionally, the arm incorporates integral feature(s) that facilitate interconnection with corresponding features of a second, identically formed PV module.

  2. Megakaryopoiesis: transcriptional insights into megakaryocyte maturation.

    PubMed

    Kostyak, John Creigh; Naik, Ulhas Pandurang

    2007-01-01

    Platelets are small anucleate cells that travel near the vessel wall during laminar flow. In response to vascular injury, platelets undergo alterations in morphology which allow them to aggregate and cover the injured site. Platelets are produced by megakaryocytes in a process that involves the formation of platelet precursors called proplatelets and subsequent release of these proplatelets into the circulation. By forming a demarcation membrane system within the cytosol, megakaryocytes contain a membrane reservoir which allows for the production of thousands of platelets per mature megakaryocyte. Interestingly, the above process known as megakaryopoiesis is not yet fully understood. However, several groups have contributed evidence to unveil the role of thrombopoietin (TPO), the principal regulator of megakaryopoiesis in vivo. TPO is necessary for megakaryocyte maturation in that TPO deficient mice display greatly reduced megakaryocyte production as well as reduced numbers of mature megakaryocytes. Several transcription factors have also been implicated in megakaryopoiesis including, GATA-1, friend of GATA-1 (FOG-1), nuclear factor-erythroid 2 (NF-E2), and Fli-1. In fact, interactions among some of the transcription factors have been reported to produce synergistic effects. GATA-1 and Fli-1 interactions result in heightened GPIX and GPIb (2 components of von Willebrand Factor (vWF) receptor) expression, while GATA-1, RUNX1 and core-binding factor beta interactions result in improved alphaIIb promoter activity. Mutations in the vWF complex and alphaIIb beta3 have been linked to disorders such as Bernard-Soulier syndrome and Glazmann thrombasthenia respectively. Therefore, a more comprehensive understanding of the transcriptional control of megakaryopoiesis may lead to more effective treatments of platelet-related disorders.

  3. Maturing Technologies for Stirling Space Power Generation

    NASA Technical Reports Server (NTRS)

    Wilson, Scott D.; Nowlin, Brentley C.; Dobbs, Michael W.; Schmitz, Paul C.; Huth, James

    2016-01-01

    Stirling Radioisotope Power Systems (RPS) are being developed as an option to provide power on future space science missions where robotic spacecraft will orbit, flyby, land or rove. A Stirling Radioisotope Generator (SRG) could offer space missions a more efficient power system that uses one fourth of the nuclear fuel and decreases the thermal footprint of the current state of the art. The RPS Program Office, working in collaboration with the U.S. Department of Energy (DOE), manages projects to develop thermoelectric and dynamic power systems, including Stirling Radioisotope Generators (SRGs). The Stirling Cycle Technology Development (SCTD) Project, located at Glenn Research Center (GRC), is developing Stirling-based subsystems, including convertors and controllers. The SCTD Project also performs research that focuses on a wide variety of objectives, including increasing convertor temperature capability to enable new environments, improving system reliability or fault tolerance, reducing mass or size, and developing advanced concepts that are mission enabling. Research activity includes maturing subsystems, assemblies, and components to prepare them for infusion into future convertor and generator designs. The status of several technology development efforts are described here. As part of the maturation process, technologies are assessed for readiness in higher-level subsystems. To assess the readiness level of the Dual Convertor Controller (DCC), a Technology Readiness Assessment (TRA) was performed and the process and results are shown. Stirling technology research is being performed by the SCTD Project for NASA's RPS Program Office, where tasks focus on maturation of Stirling-based systems and subsystems for future space science missions.

  4. A regulatory network for coordinated flower maturation.

    PubMed

    Reeves, Paul H; Ellis, Christine M; Ploense, Sara E; Wu, Miin-Feng; Yadav, Vandana; Tholl, Dorothea; Chételat, Aurore; Haupt, Ina; Kennerley, Brian J; Hodgens, Charles; Farmer, Edward E; Nagpal, Punita; Reed, Jason W

    2012-02-01

    For self-pollinating plants to reproduce, male and female organ development must be coordinated as flowers mature. The Arabidopsis transcription factors AUXIN RESPONSE FACTOR 6 (ARF6) and ARF8 regulate this complex process by promoting petal expansion, stamen filament elongation, anther dehiscence, and gynoecium maturation, thereby ensuring that pollen released from the anthers is deposited on the stigma of a receptive gynoecium. ARF6 and ARF8 induce jasmonate production, which in turn triggers expression of MYB21 and MYB24, encoding R2R3 MYB transcription factors that promote petal and stamen growth. To understand the dynamics of this flower maturation regulatory network, we have characterized morphological, chemical, and global gene expression phenotypes of arf, myb, and jasmonate pathway mutant flowers. We found that MYB21 and MYB24 promoted not only petal and stamen development but also gynoecium growth. As well as regulating reproductive competence, both the ARF and MYB factors promoted nectary development or function and volatile sesquiterpene production, which may attract insect pollinators and/or repel pathogens. Mutants lacking jasmonate synthesis or response had decreased MYB21 expression and stamen and petal growth at the stage when flowers normally open, but had increased MYB21 expression in petals of older flowers, resulting in renewed and persistent petal expansion at later stages. Both auxin response and jasmonate synthesis promoted positive feedbacks that may ensure rapid petal and stamen growth as flowers open. MYB21 also fed back negatively on expression of jasmonate biosynthesis pathway genes to decrease flower jasmonate level, which correlated with termination of growth after flowers have opened. These dynamic feedbacks may promote timely, coordinated, and transient growth of flower organs.

  5. GTPases involved in bacterial ribosome maturation.

    PubMed

    Goto, Simon; Muto, Akira; Himeno, Hyouta

    2013-05-01

    The ribosome is an RNA- and protein-based macromolecule having multiple functional domains to facilitate protein synthesis, and it is synthesized through multiple steps including transcription, stepwise cleavages of the primary transcript, modifications of ribosomal proteins and RNAs and assemblies of ribosomal proteins with rRNAs. This process requires dozens of trans-acting factors including GTP- and ATP-binding proteins to overcome several energy-consuming steps. Despite accumulation of genetic, biochemical and structural data, the entire process of bacterial ribosome synthesis remains elusive. Here, we review GTPases involved in bacterial ribosome maturation.

  6. Micropropagation of Elaeagnus angustifolia from mature trees.

    PubMed

    Iriondo, J M; De La Iglesia, M; Pérez, C

    1995-10-01

    Multiple shoots were obtained from nodal segments of mature trees of Elaeagnus angustifolia L. cultured on MS medium (Murashige and Skoog 1962) supplemented with 0, 0.88 or 2.22 micro M N(6)-benzyladenine. When nodal segments taken from the in vitro proliferated shoots were cultured under the same conditions, additional multiple shoots were obtained. Rooting of the in vitro propagated shoots was achieved on full strength MS medium or on MS supplemented with 2.46 micro M indole-3-butyric acid. Regenerated plantlets were acclimatized and successfully transplanted to soil.

  7. Performance, growth, and maturity of Nellore bulls.

    PubMed

    Costa e Silva, Luiz Fernando; Valadares Filho, Sebastião de Campos; Detmann, Edenio; Rotta, Polyana Pizzi; Zanetti, Diego; Villadiego, Faider Alberto Castaño; Pellizzoni, Samantha Gusmão; Pereira, Rafael Moura Guimarães

    2013-03-01

    The objectives of this study were to evaluate the dry matter intake (DMI), digestibility, average daily gain (ADG), microbial efficiency, empty body weight (EBW) gain, and body composition of Nellore bulls. Additionally, Nellore bull maturity was estimated, and the prediction equation for DMI, suggested by the Brazilian nutrient requirements system (BR CORTE; Azevêdo et al. 2010), was evaluated. Thirty-three Nellore bulls, with a mean initial weight of 259 ± 25 kg and age of 14 ± 1 months, were used in this study. Five animals were slaughtered at the beginning of the experiment (control group), and the remaining 28 were divided into 4 groups, each slaughtered at 42-day intervals. Their diet was composed of corn silage and concentrate (55:45). The power model was used to estimate muscle tissue, bone tissue, crude protein (CP), mineral matter (MM), and water present in the empty body, while the exponential model was used to estimate adipose tissue and ether extract (EE) present in the empty body. When expressed in kilograms per day, differences were observed (P < 0.05) only for the intake of EE and neutral detergent fiber as a function of feedlot time periods. Although there was a difference in relation to nutrient intake, it did not affect (P > 0.05) digestibility, with the exception of EE digestibility. The equation suggested by BR CORTE correctly estimates the DMI of Nellore bulls. ADG was not affected (P > 0.05) by time spent in the feedlot. No differences were observed (P > 0.05) for microbial efficiency; a mean value of 142 g microbial crude protein/kg total digestible nutrients was achieved. The muscle and bone tissues, CP, MM, and water present in the empty body increased as the animal grew, although at a lower rate. The adipose tissue and EE present in the empty body increased their deposition rate when the animal reached its mature weight. Maturity is defined as when an animal reaches 22 % EE in the empty body, which

  8. Maturation-Resistant Dendritic Cells Ameliorate Experimental Autoimmune Uveoretinitis

    PubMed Central

    Oh, Keunhee; Kim, Yon Su

    2011-01-01

    Background Endogenous uveitis is a chronic inflammatory eye disease of human, which frequently leads to blindness. Experimental autoimmune uveoretinitis (EAU) is an animal disease model of human endogenous uveitis and can be induced in susceptible animals by immunization with retinal antigens. EAU resembles the key immunological characteristics of human disease in that both are CD4+ T-cell mediated diseases. Dendritic cells (DCs) are specialized antigen-presenting cells that are uniquely capable of activating naïve T cells. Regulation of immune responses through modulation of DCs has thus been tried extensively. Recently our group reported that donor strain-derived immature DC pretreatment successfully controlled the adverse immune response during allogeneic transplantation. Methods EAU was induced by immunization with human interphotoreceptor retinoid-binding protein (IRBP) peptide1-20. Dendritic cells were differentiated from bone marrow in the presence of recombinant GM-CSF. Results In this study, we used paraformaldehyde-fixed bone marrow-derived DCs to maintain them in an immature state. Pretreatment with fixed immature DCs, but not fixed mature DCs, ameliorated the disease progression of EAU by inhibiting uveitogenic CD4+ T cell activation and differentiation. Conclusion Application of iBMDC prepared according to the protocol of this study would provide an important treatment modality for the autoimmune diseases and transplantation rejection. PMID:22346781

  9. Bacterial biosynthesis and maturation of the didemnin anticancer agents

    PubMed Central

    Xu, Ying; Kersten, Roland D.; Nam, Sang-Jip; Lu, Liang; Al-Suwailem, Abdulaziz M.; Zheng, Huajun; Fenical, William; Dorrestein, Pieter C.

    2012-01-01

    The antineoplastic agent didemnin B from the Caribbean tunicate Trididemnum solidum was the first marine drug to be clinically tested in humans. Because of its limited supply and its complex cyclic depsipeptide structure, considerable challenges were encountered during didemnin B's development that continue to limit aplidine (dehydrodidemnin B), which is currently being evaluated in numerous clinical trials. Herein we show that the didemnins are bacterial products produced by the marine α-proteobacteria Tistrella mobilis and Tistrella bauzanensis via a unique post-assembly line maturation process. Complete genome sequence analysis of the 6,513,401 bp T. mobilis strain KA081020-065 with its five circular replicons revealed the putative didemnin biosynthetic gene cluster (did) on the 1,126,962 bp megaplasmid pTM3. The did locus encodes a 13-module hybrid nonribosomal peptide synthetase-polyketide synthase enzyme complex organized in a co-linear arrangement for the synthesis of the fatty acylglutamine ester derivatives didemnins X and Y rather than didemnin B as first anticipated. Imaging mass spectrometry of T. mobilis bacterial colonies captured the time-dependent extracellular conversion of the didemnin X and Y precursors to didemnin B in support of an unusual post-synthetase activation mechanism. Significantly, the discovery of the didemnin biosynthetic gene cluster may provide a long-term solution to the supply problem that presently hinders this group of marine natural products and pave the way for the genetic engineering of new didemnin congeners. PMID:22458477

  10. Mycobacterium tuberculosis Promotes Anti-apoptotic Activity of the Macrophage by PtpA Protein-dependent Dephosphorylation of Host GSK3α*

    PubMed Central

    Poirier, Valérie; Bach, Horacio; Av-Gay, Yossef

    2014-01-01

    Mycobacterium tuberculosis tyrosine phosphatase PtpA inhibits two key cellular events in macrophages required for the elimination of invading organisms, phagosome acidification, and maturation. Kinome analysis revealed multiple PtpA-dependent changes to the phosphorylation status of macrophage proteins upon M. tuberculosis infection. Among those proteins we show that PtpA dephosphorylates GSK3α on amino acid Tyr279, which leads to modulation of GSK3α anti-apoptotic activity, promoting pathogen survival early during infection. PMID:25187516

  11. Developmental effects of wheel running on hippocampal glutamate receptor expression in young and mature adult rats.

    PubMed

    Staples, M C; Somkuwar, S S; Mandyam, C D

    2015-10-01

    Recent evidence suggests that the behavioral benefits associated with voluntary wheel running in rodents may be due to modulation of glutamatergic transmission in the hippocampus, a brain region implicated in learning and memory. However, the expression of the glutamatergic ionotropic N-methyl-d-aspartate receptor (GluN) in the hippocampus in response to chronic sustained voluntary wheel running has not yet been investigated. Further, the developmental effects during young and mature adulthood on wheel running output and GluN expression in hippocampal subregions has not been determined, and therefore is the main focus of this investigation. Eight-week-old and 16-week-old male Wistar rats were housed in home cages with free access to running wheels and running output was monitored for 4weeks. Wheel access was terminated and tissues from the dorsal and ventral hippocampi were processed for Western blot analysis of GluN subunit expression. Young adult runners demonstrated an escalation in running output but this behavior was not evident in mature adult runners. In parallel, young adult runners demonstrated a significant increase in total GluN (1 and 2A) subunit expression in the dorsal hippocampus (DH), and an opposing effect in the ventral hippocampus (VH) compared to age-matched sedentary controls; these changes in total protein expression were not associated with significant alterations in the phosphorylation of the GluN subunits. In contrast, mature adult runners demonstrated a reduction in total GluN2A expression in the DH, without producing alterations in the VH compared to age-matched sedentary controls. In conclusion, differential running activity-mediated modulation of GluN subunit expression in the hippocampal subregions was revealed to be associated with developmental effects on running activity, which may contribute to altered hippocampal synaptic activity and behavioral outcomes in young and mature adult subjects.

  12. Validation of the Psychological Work Maturity Scale in Chinese employees.

    PubMed

    Tong, Jiajin; Wang, Lei

    2010-12-01

    Psychological work maturity is an important concept in situational leadership theory. The present research revised the Psychological Work Maturity Scale for use in Chinese organizations. Three samples of full-time employees (Ns = 205, 266, and 283) from different companies and industries participated in the present study. Confirmatory factor analysis showed that a single-factor structure fit the data. The scale had acceptable reliabilities, convergent and criterion-related validities, and was shown to be an appropriate measure of psychological work maturity in Chinese employees. Maturity differences in several demographic variables were not found, but employees with longer tenure in Sample 2 scored higher on maturity, which shows that psychological work maturity may be dependent on personal development in the interaction with the varying situational factors, especially in the work domain. Implications for research and practice on psychological work maturity in China are discussed.

  13. The insemination of goldfish ( Carassium auratus) oocyte matured in vitro

    NASA Astrophysics Data System (ADS)

    Wang, Renxue; Wu, Xianhan; Zhou, Jing; Zhang, Shicui; Ma, Yingjie; Wu, Shangqin; Shi, Yingxian

    1991-03-01

    Full maturation of goldfish oocyte was induced in vitro by 17 α-hydroxy-20β-dihydroprogesterone. The oocyte maturation involves GV migration to the periphery of the oocyte and germinal vesicle breakdown (GVBD). In the experiment, incubation duration for GVBD varied in different broods of oocytes. Generally, if the duration for GVBD was shorter than 6 h, oocytes would have a better chance to survive after maturation and insemination. The maturation of nucleus (GV) and cytoplasm are not synchronous. Cytoplasm maturation occurs several hs after GVBD. Oocytes inseminated 8 9 h after GVBD have the highest fertilizing and hatching rate. Fertilized ova matured in vitro can develop to sexually mature adults capable of reproduction.

  14. Pitch perception prior to cortical maturation

    NASA Astrophysics Data System (ADS)

    Lau, Bonnie K.

    Pitch perception plays an important role in many complex auditory tasks including speech perception, music perception, and sound source segregation. Because of the protracted and extensive development of the human auditory cortex, pitch perception might be expected to mature, at least over the first few months of life. This dissertation investigates complex pitch perception in 3-month-olds, 7-month-olds and adults -- time points when the organization of the auditory pathway is distinctly different. Using an observer-based psychophysical procedure, a series of four studies were conducted to determine whether infants (1) discriminate the pitch of harmonic complex tones, (2) discriminate the pitch of unresolved harmonics, (3) discriminate the pitch of missing fundamental melodies, and (4) have comparable sensitivity to pitch and spectral changes as adult listeners. The stimuli used in these studies were harmonic complex tones, with energy missing at the fundamental frequency. Infants at both three and seven months of age discriminated the pitch of missing fundamental complexes composed of resolved and unresolved harmonics as well as missing fundamental melodies, demonstrating perception of complex pitch by three months of age. More surprisingly, infants in both age groups had lower pitch and spectral discrimination thresholds than adult listeners. Furthermore, no differences in performance on any of the tasks presented were observed between infants at three and seven months of age. These results suggest that subcortical processing is not only sufficient to support pitch perception prior to cortical maturation, but provides adult-like sensitivity to pitch by three months.

  15. Developmental plasticity in child growth and maturation.

    PubMed

    Hochberg, Ze'ev

    2011-01-01

    The ability of a given genotype to produce different phenotypes in response to different environments is termed "plasticity," and is part of the organism's "adaptability" to environmental cues. The expressions of suites of genes, particularly during development or life history transitions, probably underlie the fundamental plasticity of an organism. Plasticity in developmental programming has evolved in order to provide the best chances of survival and reproductive success to organisms under changing environments. Environmental conditions that are experienced in early life can profoundly influence human biology, child growth and maturation, and long-term health and longevity. Developmental origins of health and disease and life history transitions are purported to use placental, nutritional, and endocrine cues for setting long-term biological, mental, and behavioral strategies for child growth and maturation in response to local ecological and/or social conditions. The window of developmental plasticity extends from conception to early childhood, and even beyond to the transition from juvenility to adolescence, and could be transmitted transgenerationally. It involves epigenetic responses to environmental changes, which exert their effects during life history phase transitions.

  16. Schlafen 3 changes during rat intestinal maturation

    PubMed Central

    Walsh, Mary F.; Hermann, Rebecca; Sun, Kelian; Basson, Marc D.

    2015-01-01

    BACKGROUND Understanding gut development may illuminate the adaptive response to massive small-bowel resection and facilitate enteral nutrition. We reported that Schlafen-3 (Slfn3) mediates differentiation in vitro in rat intestinal epithelial. We hypothesized that Slfn3 is involved in intestinal development in vivo. METHODS We removed fetal intestines, liver, and lungs on day 20 of gestation, at birth, and on postnatal days 1 and 5. Expression of Slfn3, markers of intestinal differentiation, and Slfn5, to address specificity, were determined by quantitative reverse-transcription polymerase chain reaction. RESULTS Villin expression increased on days 1 and 5 (8.7 ± .6 and 5.4 ± .4, respectively; P < .01). Intestinal Slfn3 expression was increased substantially after birth (2.1- ± .5-fold) and on days 1 and 5 (P < .02). Slfn3 was higher after birth in liver and lung but decreased sharply thereafter. Slfn5 expression was mostly unchanged. CONCLUSIONS The data suggest that the developmental/maturation effects we observed correlate with Slfn3 but not Slfn5 and are more relevant to the intestines. A better understanding of how Slfn3 promotes intestinal differentiation could help promote intestinal maturation, improving outcomes in children or adults with short-gut syndrome. PMID:22906252

  17. 176 REGULATORY ROLE OF miR-20a DURING BOVINE OOCYTE MATURATION.

    PubMed

    Andreas, E; Salilew-Wondim, D; Rings, F; Held, E; Hoelker, M; Neuhoff, C; Tholen, E; Schellander, K; Tesfaye, D

    2016-01-01

    GmbH, Loerrach, Germany). Here, we found that miR-20a expression in cumulus cells increased (P<0.05) during oocyte maturation. Conversely, miR-20a expression in metaphase II stage oocytes was significantly lower (P<0.001) compared with the germinal vesicle stage. The absence of oocyte cytoplasm resulted in reduced miR-20a expression in cumulus cells. On the other hand, the absent of cumulus cells increased miR-20a expression in oocytes. The miR-20a expression revealed that the microRNA transduction is restricted in the cumulus cells. The overexpression of miR-20a increased oocyte maturation rate (P<0.05) by 4.8% (as determined by extrusion of the polar body) and the expression of oocyte maturation-related genes (INHBA, MAPK1, PTGS2, PTX3, and EGFR). The progesterone released in spent media of COC co-cultured with miR-20a mimic and inhibitor showed increasing (P=0.0936) and decreasing (P=0.0993) trends, respectively. In this study, we also found that miR-20a modulation altered the expression of PTEN and BMPR2 in cumulus cells. In conclusion, the modulation of miR-20a expression in cumulus cells regulates the oocyte maturation and partially involved in the progesterone synthesis by fine-tuning the expression of PTEN and BMPR2 genes.

  18. Tyro3 Modulates Mertk-Associated Retinal Degeneration.

    PubMed

    Vollrath, Douglas; Yasumura, Douglas; Benchorin, Gillie; Matthes, Michael T; Feng, Wei; Nguyen, Natalie M; Sedano, Cecilia D; Calton, Melissa A; LaVail, Matthew M

    2015-12-01

    Inherited photoreceptor degenerations (IPDs) are the most genetically heterogeneous of Mendelian diseases. Many IPDs exhibit substantial phenotypic variability, but the basis is usually unknown. Mutations in MERTK cause recessive IPD phenotypes associated with the RP38 locus. We have identified a murine genetic modifier of Mertk-associated photoreceptor degeneration, the C57BL/6 (B6) allele of which acts as a suppressor. Photoreceptors degenerate rapidly in Mertk-deficient animals homozygous for the 129P2/Ola (129) modifier allele, whereas animals heterozygous for B6 and 129 modifier alleles exhibit an unusual intermixing of degenerating and preserved retinal regions, with females more severely affected than males. Mertk-deficient mice homozygous for the B6 modifier allele display degeneration only in the far periphery, even at 8 months of age, and have improved retinal function compared to animals homozygous for the 129 allele. We genetically mapped the modifier to an approximately 2-megabase critical interval that includes Tyro3, a paralog of Mertk. Tyro3 expression in the outer retina varies with modifier genotype in a manner characteristic of a cis-acting expression quantitative trait locus (eQTL), with the B6 allele conferring an approximately three-fold higher expression level. Loss of Tyro3 function accelerates the pace of photoreceptor degeneration in Mertk knockout mice, and TYRO3 protein is more abundant in the retinal pigment epithelium (RPE) adjacent to preserved central retinal regions of Mertk knockout mice homozygous for the B6 modifier allele. Endogenous human TYRO3 protein co-localizes with nascent photoreceptor outer segment (POS) phagosomes in a primary RPE cell culture assay, and expression of murine Tyro3 in cultured cells stimulates phagocytic ingestion of POS. Our findings demonstrate that Tyro3 gene dosage modulates Mertk-associated retinal degeneration, provide strong evidence for a direct role for TYRO3 in RPE phagocytosis, and suggest

  19. FOXO3-mTOR Metabolic Cooperation in the Regulation of Erythroid Cell Maturation and Homeostasis

    PubMed Central

    Zhang, Xin; Campreciós, Genís; Rimmelé, Pauline; Liang, Raymond; Yalcin, Safak; Mungamuri, Sathish Kumar; Barminko, Jeffrey; D’Escamard, Valentina; Baron, Margaret H.; Brugnara, Carlo; Papatsenko, Dmitri; Rivella, Stefano; Ghaffari, Saghi

    2014-01-01

    Ineffective erythropoiesis is observed in many erythroid disorders including β-thalassemia and anemia of chronic disease in which increased production of erythroblasts that fail to mature exacerbate the underlying anemias. As loss of the transcription factor FOXO3 results in erythroblast abnormalities similar to the ones observed in ineffective erythropoiesis, we investigated the underlying mechanisms of the defective Foxo3−/− erythroblast cell cycle and maturation. Here we show that loss of Foxo3 results in overactivation of the JAK2/AKT/mTOR signaling pathway in primary bone marrow erythroblasts partly mediated by redox modulation. We further show that hyperactivation of mTOR signaling interferes with cell cycle progression in Foxo3 mutant erythroblasts. Importantly, inhibition of mTOR signaling, in vivo or in vitro enhances significantly Foxo3 mutant erythroid cell maturation. Similarly, in vivo inhibition of mTOR remarkably improves erythroid cell maturation and anemia in a model of β-thalassemia. Finally we show that FOXO3 and mTOR are likely part of a larger metabolic network in erythroblasts as together they control the expression of an array of metabolic genes some of which are implicated in erythroid disorders. These combined findings indicate that a metabolism-mediated regulatory network centered by FOXO3 and mTOR control the balanced production and maturation of erythroid cells. They also highlight physiological interactions between these proteins in regulating erythroblast energy. Our results indicate that alteration in the function of this network might be implicated in the pathogenesis of ineffective erythropoiesis. PMID:24966026

  20. Moving Toward Quantifying Reliability - The Next Step in a Rapidly Maturing PV Industry: Preprint

    SciTech Connect

    Kurtz, Sarah; Sample, Tony; Wohlgemuth, John; Zhou, Wei; Bosco, Nick; Althaus, Joerg; Phillips, Nancy; Deceglie, Michael; Flueckiger, Chris; Hacke, Peter; Miller, David; Kempe, Michael; Yamamichi, Masaaki; Kondo, Michio

    2015-12-07

    Some may say that PV modules are moving toward being a simple commodity, but most major PV customers ask: 'How can I minimize chances of a module recall?' Or, 'How can I quantify the added value of a 'premium' module?' Or, 'How can I assess the value of an old PV system that I'm thinking of purchasing?' These are all questions that PVQAT (the International PV Quality Assurance Task Force) and partner organizations are working to answer. Defining standard methods for ensuring minimal acceptable quality of PV modules, differentiating modules that provide added value in the toughest of environments, and creating a process (e.g. through IECRE [1]) that can follow a PV system from design through installation and operation are tough tasks, but having standard approaches for these will increase confidence, reduce costs, and be a critical foundation of a mature PV industry. This paper summarizes current needs for new tests, some challenges for defining those tests, and some of the key efforts toward development of international standards, emphasizing that meaningful quantification of reliability (as in defining a service life prediction) must be done in the context of a specific product with design parameters defined through a quality management system.

  1. Transcriptional determinants of tolerogenic and immunogenic states during dendritic cell maturation

    PubMed Central

    Vander Lugt, Bryan; Riddell, Jeremy; Khan, Aly A.; Lesch, Justin; DeVoss, Jason; Weirauch, Matthew T.

    2017-01-01

    Dendritic cells (DCs) promote either tolerogenic or immunogenic T cell responses, the latter upon sensing microbes. Using an in vitro system, we analyzed transcriptional determinants that enable mature DCs to direct these opposing T cell outcomes. In the absence of microbial products, the transcription factor interferon regulatory factor 4 (IRF4) promotes regulatory T cell (Treg) generation by enhancing expression of genes required for antigen presentation along with those for T cell tolerance. IRF4-deficient DCs were impaired for Treg generation in vivo. When exposed to microbial stimuli, DCs activated nuclear factor (NF)-κB, which induced expression of a proinflammatory cytokine module that, along with the antigen presentation module, promoted the generation of effector T cells. NF-κB was, however, dispensable for Treg development. Chromatin profiling revealed transcriptional motifs associated with the divergent DC programs. Thus, DCs modulate their ability to prime tolerogenic or immunogenic T cells by expressing a core antigen presentation module that is overlaid by distinctive regulatory modules to promote either tolerance or immunity. PMID:28130292

  2. Moving Toward Quantifying Reliability - The Next Step in a Rapidly Maturing PV Industry

    SciTech Connect

    Kurtz, Sarah; Sample, Tony; Wohlgemuth, John; Zhou, Wei; Bosco, Nick; Althaus, Joerg; Phillips, Nancy; Deceglie, Michael; Flueckiger, Chris; Hacke, Peter; Miller, David; Kempe, Michael; Yamamichi, Masaaki; Kondo, Michio

    2015-06-14

    Some may say that PV modules are moving toward being a simple commodity, but most major PV customers ask: 'How can I minimize chances of a module recall?' Or, 'How can I quantify the added value of a 'premium' module?' Or, 'How can I assess the value of an old PV system that I'm thinking of purchasing?' These are all questions that PVQAT (the International PV Quality Assurance Task Force) and partner organizations are working to answer. Defining standard methods for ensuring minimal acceptable quality of PV modules, differentiating modules that provide added value in the toughest of environments, and creating a process (e.g. through IECRE [1]) that can follow a PV system from design through installation and operation are tough tasks, but having standard approaches for these will increase confidence, reduce costs, and be a critical foundation of a mature PV industry. This paper summarizes current needs for new tests, some challenges for defining those tests, and some of the key efforts toward development of international standards, emphasizing that meaningful quantification of reliability (as in defining a service life prediction) must be done in the context of a specific product with design parameters defined through a quality management system.

  3. Do people who “Mature Out” of drinking see themselves as more mature?

    PubMed Central

    Winograd, Rachel P.; Littlefield, Andrew K.; Sher, Kenneth J.

    2012-01-01

    Background Self-perceptions of adulthood during the 20's and 30's are influenced by role transitions, age-related norms, and character traits, factors that are also associated with alcohol use disorders (AUDs) whose prevalence peaks and subsequently decreases during this time of life. Previous developmental research has found that alcohol misuse in adolescence predicts lower reported maturity whereas alcohol misuse in emerging adulthood is not related to maturity. This study examines how self-perceived maturity (SPM) is affected by AUD status, maturity-related personality characteristics, and role transition variables at ages 25, 29, and 35, and how those relationships change over time. Methods Data were drawn from a cohort study of 410 college students (N = 489 at baseline). Students were ascertained as first-time freshman at a large, public Midwestern university in the fall of 1987 but were followed up regardless of subsequent enrollment. The data for the current study was drawn from waves 5–7, when participants were, on average, 25, 29, and 35 years of age. Structural equation modeling was used to determine if the relation between the SPM item “I feel mature for my age” and DSM-III alcohol use disorder (AUD) status was moderated by age. Results Results suggested that individuals with AUDS are more likely to endorse lower SPM levels compared to their non-diagnosing peers at ages 29 and 35 but not at age 25. In contrast, none of the relations between Conscientiousness, concern about future consequences, role status variables and AUD was moderated by time. Conclusion These results suggest that alcohol-related problems may be perceived as more “age appropriate” during the mid-twenties than at later ages in life, and that such developmentally-sensitive aspects of self-concept might be useful in cognitive interventions for young adults. PMID:22324647

  4. Effect of thrombin on maturing human megakaryocytes.

    PubMed Central

    Cramer, E. M.; Massé, J. M.; Caen, J. P.; Garcia, I.; Breton-Gorius, J.; Debili, N.; Vainchenker, W.

    1993-01-01

    Thrombin causes platelet activation and secretion. In some nucleated cells, it is mitogenic. In this study, we have investigated how human megakaryocytes (MKs) respond to this agonist and whether the response depends on the maturation stage. MKs were cultured from bone marrow precursors in liquid culture in the presence of normal plasma. To determine whether thrombin can activate MKs, 14-day MK cultures were incubated with thrombin for 5 minutes, and cells were studied by electron microscopy, either by standard techniques or after embedding in glycol-methacrylate for immunoelectron microscopy. Ultrastructural examination of thrombin-treated MKs revealed dramatic morphological changes reminiscent of those found in platelets, including shape change and organelle centralization that involved immature as well as mature cells. MKs were also able to secrete alpha-granule proteins in the dilated cisternae of the demarcation membrane system, as shown by immunogold staining for thrombospondin and glycoprotein Ib. These changes were rapid (less than 5 minutes) but despite them, MKs remained viable for more than 24 hours. To determine whether thrombin has a mitogenic activity, it was added to the culture of MKs from day 3 to day 10 of culture at concentrations varying from 0.1 to 10 U/ml. Cells were subsequently studied by a double staining technique using flow cytometry to determine MK number and ploidy. No changes were observed in these two parameters, showing that thrombin is not mitogenic for MKs at the concentrations used. In conclusion, this study confirms for human MKs previous observations made about guinea pig MKs (Fedorko et al, Lab Invest 1977, 36:32). In addition, it demonstrates that immature MKs are able to respond to thrombin and that more mature cells can secrete alpha-granule proteins into the demarcation membrane system, which is in continuity with the extracellular space. This phenomenon may have implications for pathological states such as myelofibrosis

  5. Sexual selection shapes development and maturation rates in Drosophila.

    PubMed

    Hollis, Brian; Keller, Laurent; Kawecki, Tadeusz J

    2017-02-01

    Explanations for the evolution of delayed maturity usually invoke trade-offs mediated by growth, but processes of reproductive maturation continue long after growth has ceased. Here, we tested whether sexual selection shapes the rate of posteclosion maturation in the fruit fly Drosophila melanogaster. We found that populations maintained for more than 100 generations under a short generation time and polygamous mating system evolved faster posteclosion maturation and faster egg-to-adult development of males, when compared to populations kept under short generations and randomized monogamy that eliminated sexual selection. An independent assay demonstrated that more mature males have higher fitness under polygamy, but this advantage disappears under monogamy. In contrast, for females greater maturity was equally advantageous under polygamy and monogamy. Furthermore, monogamous populations evolved faster development and maturation of females relative to polygamous populations, with no detectable trade-offs with adult size or egg-to-adult survival. These results suggest that a major aspect of male maturation involves developing traits that increase success in sexual competition, whereas female maturation is not limited by investment in traits involved in mate choice or defense against male antagonism. Moreover, rates of juvenile development and adult maturation can readily evolve in opposite directions in the two sexes, possibly implicating polymorphisms with sexually antagonistic pleiotropy.

  6. Extrasynaptic vesicle recycling in mature hippocampal neurons.

    PubMed

    Ratnayaka, Arjuna; Marra, Vincenzo; Branco, Tiago; Staras, Kevin

    2011-11-08

    Fast neuronal signalling relies on highly regulated vesicle fusion and recycling at specialized presynaptic terminals. Recently, examples of non-classical neurotransmission have also been reported, where fusion of vesicles can occur at sites remote from conventional synapses. This has potentially broad biological implications, but the underlying mechanisms are not well established. Here we show that a complete vesicle recycling pathway can occur at discrete axonal sites in mature hippocampal neurons and that extrasynaptic fusion is a robust feature of native tissue. We demonstrate that laterally mobile vesicle clusters trafficking between synaptic terminals become transiently stabilized by evoked action potentials and undergo complete but delayed Ca(2+)-dependent fusion along axons. This fusion is associated with dynamic actin accumulation and, subsequently, vesicles can be locally recycled, re-acidified and re-used. Immunofluorescence and ultrastructural work demonstrates that extrasynaptic fusion sites can have apposed postsynaptic specializations, suggesting that mobile vesicle recycling may underlie highly dynamic neuron-neuron communication.

  7. Anabolic actions of Notch on mature bone

    PubMed Central

    Liu, Peng; Ping, Yilin; Ma, Meng; Zhang, Demao; Liu, Connie; Zaidi, Samir; Gao, Song; Ji, Yaoting; Lou, Feng; Yu, Fanyuan; Lu, Ping; Stachnik, Agnes; Bai, Mingru; Wei, Chengguo; Zhang, Liaoran; Wang, Ke; Chen, Rong; New, Maria I.; Rowe, David W.; Yuen, Tony; Sun, Li; Zaidi, Mone

    2016-01-01

    Notch controls skeletogenesis, but its role in the remodeling of adult bone remains conflicting. In mature mice, the skeleton can become osteopenic or osteosclerotic depending on the time point at which Notch is activated or inactivated. Using adult EGFP reporter mice, we find that Notch expression is localized to osteocytes embedded within bone matrix. Conditional activation of Notch signaling in osteocytes triggers profound bone formation, mainly due to increased mineralization, which rescues both age-associated and ovariectomy-induced bone loss and promotes bone healing following osteotomy. In parallel, mice rendered haploinsufficient in γ-secretase presenilin-1 (Psen1), which inhibits downstream Notch activation, display almost-absent terminal osteoblast differentiation. Consistent with this finding, pharmacologic or genetic disruption of Notch or its ligand Jagged1 inhibits mineralization. We suggest that stimulation of Notch signaling in osteocytes initiates a profound, therapeutically relevant, anabolic response. PMID:27036007

  8. PERSISTENT WRIST PAIN IN A MATURE GOLFER

    PubMed Central

    Hazle, Charles

    2012-01-01

    Clients presenting with ulnar-sided wrist pain can provide diagnostic and management challenges for physical therapists. Symptoms in this region may originate from multiple structures. Integration of clinical examination and diagnostic imaging results is often required for optimal decision-making and patient management. To obtain the most informative imaging results, practitioners need an understanding of injury patterns and their detection by various imaging modalities. This case describes a mature golfer who presented with persistent ulnar-sided wrist pain and was eventually determined to have a fracture of the hook of the hamate accompanied by neighboring soft tissue involvement also contributing to his symptom complex. His history and the diagnostic process are detailed along with a brief discussion of his subsequent management post-operatively. Level of Evidence: 5 (Single Case Report) PMID:22893862

  9. Exploration maturity key to ranking search areas

    USGS Publications Warehouse

    Attanasi, E.D.; Freeman, P.A.

    2008-01-01

    The study area of US Geological Survey Circular 1288, the world outside the US and Canada, was partitioned into 44 countries and country groups. Map figures such as Fig. 2 and graphs similar to Figs. 3 and 4 provide a visual summary of maturity of oil and gas exploration. From 1992 through 2001, exploration data show that in the study area the delineated prospective area expanded at a rate of about 50,000 sq miles/year, while the explored area grew at a rate of 11,000 sq miles/year. The delineated prospective area established by 1970 accounts for less than 40% of total delineated prospective area but contains 75% of the oil discovered to date in the study area. From 1991 through 2000, offshore discoveries accounted for 59% of the oil and 77% of the gas discovered in the study area.

  10. MATURATION OF THE IMMUNE RESPONSE IN VITRO

    PubMed Central

    Macario, Alberto J. L.; de Macario, Everly Conway; Franceschi, Claudio; Celada, Franco

    1972-01-01

    We have cultivated lymph node microfragments from β-D-galactosidase (Escherichia coli) primed rabbits and have measured their secondary response directed towards the whole molecule (precipitating antibodies) and to a single determinant (activating antibodies) of the antigen. By decreasing the size of the fragments to 105 cells, we began to observe heterogeneity among identical cultures in terms of positivity of response, antibody specificity, and titers. The affinity of "early" activating antibodies was inversely proportional to the dose of challenge. While no maturation was seen in low and excessive challenge, in all cultures receiving intermediate doses the association constant was raised several orders of magnitude within periods of 20 days. The relevance of these data to the mechanism of affinity selection of antigen-sensitive cells is discussed. PMID:4557772

  11. Supported PV module assembly

    DOEpatents

    Mascolo, Gianluigi; Taggart, David F.; Botkin, Jonathan D.; Edgett, Christopher S.

    2013-10-15

    A supported PV assembly may include a PV module comprising a PV panel and PV module supports including module supports having a support surface supporting the module, a module registration member engaging the PV module to properly position the PV module on the module support, and a mounting element. In some embodiments the PV module registration members engage only the external surfaces of the PV modules at the corners. In some embodiments the assembly includes a wind deflector with ballast secured to a least one of the PV module supports and the wind deflector. An array of the assemblies can be secured to one another at their corners to prevent horizontal separation of the adjacent corners while permitting the PV modules to flex relative to one another so to permit the array of PV modules to follow a contour of the support surface.

  12. Effect of sericin supplementation during in vitro maturation on the maturation, fertilization and development of porcine oocytes.

    PubMed

    Do, L T K; Namula, Z; Luu, V V; Sato, Y; Taniguchi, M; Isobe, T; Kikuchi, K; Otoi, T

    2014-04-01

    This study aimed to examine the effects of sericin supplementation during in vitro oocyte maturation on the nuclear maturation, fertilization and development of porcine oocytes. Cumulus-oocyte complexes (COCs) were cultured in maturation medium supplemented with 0 (control), 0.1, 0.5, 1.0, 2.5 or 5.0% sericin and were then subjected to in vitro fertilization and embryo culture. More COCs matured with 1.0% sericin underwent germinal vesicle breakdown and reached metaphase II compared with the control COCs matured without sericin (p < 0.01). The proportions of oocytes with DNA-fragmented nuclei did not differ between the groups, regardless of the sericin level. The total fertilization rate of oocytes matured with 1.0% sericin was higher (p < 0.05) than that of oocytes matured with 0.1%, 2.5% and 5.0% sericin. Supplementation with more than 1.0% sericin decreased the DNA fragmentation index of the blastocysts compared with the control group (p < 0.05). However, the supplementation of the maturation medium with sericin had no beneficial effects on the cleavage, development to the blastocyst stage and the total cell number of the embryos. Our findings indicate that supplementation with 1.0% sericin during maturation culture may improve the nuclear maturation and the quality of the embryos but does not affect blastocyst formation.

  13. Healthcare quality maturity assessment model based on quality drivers.

    PubMed

    Ramadan, Nadia; Arafeh, Mazen

    2016-04-18

    Purpose - Healthcare providers differ in their readiness and maturity levels regarding quality and quality management systems applications. The purpose of this paper is to serve as a useful quantitative quality maturity-level assessment tool for healthcare organizations. Design/methodology/approach - The model proposes five quality maturity levels (chaotic, primitive, structured, mature and proficient) based on six quality drivers: top management, people, operations, culture, quality focus and accreditation. Findings - Healthcare managers can apply the model to identify the status quo, quality shortcomings and evaluating ongoing progress. Practical implications - The model has been incorporated in an interactive Excel worksheet that visually displays the quality maturity-level risk meter. The tool has been applied successfully to local hospitals. Originality/value - The proposed six quality driver scales appear to measure healthcare provider maturity levels on a single quality meter.

  14. Strawberry Maturity Neural Network Detectng System Based on Genetic Algorithm

    NASA Astrophysics Data System (ADS)

    Xu, Liming

    The quick and non-detective detection of agriculture product is one of the measures to increase the precision and productivity of harvesting and grading. Having analyzed H frequency of different maturities in different light intensities, the results show that H frequency for the same maturity has little influence in different light intensities; Under the same light intensity, three strawberry maturities are changing in order. After having confirmed the H frequency section to distinguish the different strawberry maturity, the triplelayer feed-forward neural network system to detect strawberry maturity was designed by using genetic algorithm. The test results show that the detecting precision ratio is 91.7%, it takes 160ms to distinguish one strawberry. Therefore, the online non-detective detecting the strawberry maturity could be realized.

  15. Metatranscriptomics reveals temperature-driven functional changes in microbiome impacting cheese maturation rate.

    PubMed

    De Filippis, Francesca; Genovese, Alessandro; Ferranti, Pasquale; Gilbert, Jack A; Ercolini, Danilo

    2016-02-25

    Traditional cheeses harbour complex microbial consortia that play an important role in shaping typical sensorial properties. However, the microbial metabolism is considered difficult to control. Microbial community succession and the related gene expression were analysed during ripening of a traditional Italian cheese, identifying parameters that could be modified to accelerate ripening. Afterwards, we modulated ripening conditions and observed consistent changes in microbial community structure and function. We provide concrete evidence of the essential contribution of non-starter lactic acid bacteria in ripening-related activities. An increase in the ripening temperature promoted the expression of genes related to proteolysis, lipolysis and amino acid/lipid catabolism and significantly increases the cheese maturation rate. Moreover, temperature-promoted microbial metabolisms were consistent with the metabolomic profiles of proteins and volatile organic compounds in the cheese. The results clearly indicate how processing-driven microbiome responses can be modulated in order to optimize production efficiency and product quality.

  16. Metatranscriptomics reveals temperature-driven functional changes in microbiome impacting cheese maturation rate

    SciTech Connect

    De Filippis, Francesca; Genovese, Alessandro; Ferranti, Pasquale; Gilbert, Jack A.; Ercolini, Danilo

    2016-02-25

    Traditional cheeses harbour complex microbial consortia that play an important role in shaping typical sensorial properties. However, the microbial metabolism is considered difficult to control. Microbial community succession and the related gene expression were analysed during ripening of a traditional Italian cheese, identifying parameters that could be modified to accelerate ripening. Afterwards, we modulated ripening conditions and observed consistent changes in microbial community structure and function. We provide concrete evidence of the essential contribution of non-starter lactic acid bacteria in ripening-related activities. An increase in the ripening temperature promoted the expression of genes related to proteolysis, lipolysis and amino acid/lipid catabolism and significantly increases the cheese maturation rate. Moreover, temperature-promoted microbial metabolisms were consistent with the metabolomic profiles of proteins and volatile organic compounds in the cheese. Finally, the results clearly indicate how processing-driven microbiome responses can be modulated in order to optimize production efficiency and product quality.

  17. Metatranscriptomics reveals temperature-driven functional changes in microbiome impacting cheese maturation rate

    PubMed Central

    De Filippis, Francesca; Genovese, Alessandro; Ferranti, Pasquale; Gilbert, Jack A.; Ercolini, Danilo

    2016-01-01

    Traditional cheeses harbour complex microbial consortia that play an important role in shaping typical sensorial properties. However, the microbial metabolism is considered difficult to control. Microbial community succession and the related gene expression were analysed during ripening of a traditional Italian cheese, identifying parameters that could be modified to accelerate ripening. Afterwards, we modulated ripening conditions and observed consistent changes in microbial community structure and function. We provide concrete evidence of the essential contribution of non-starter lactic acid bacteria in ripening-related activities. An increase in the ripening temperature promoted the expression of genes related to proteolysis, lipolysis and amino acid/lipid catabolism and significantly increases the cheese maturation rate. Moreover, temperature-promoted microbial metabolisms were consistent with the metabolomic profiles of proteins and volatile organic compounds in the cheese. The results clearly indicate how processing-driven microbiome responses can be modulated in order to optimize production efficiency and product quality. PMID:26911915

  18. An Analysis of Factors Affecting Mature Age Students' Academic Success in Undergraduate Nursing Programs: A Critical Literature Review.

    PubMed

    Hayden, Lisa J; Jeong, Sarah Y; Norton, Carol A

    2016-01-01

    The population of mature age students entering university nursing programs has steadily increased in both Australia and worldwide. The objective of the literature review was to explore how mature age students perform academically and to analyse the factors associated with their academic performance in nursing programs. A literature search was conducted in the following databases: CINAHL, ProQuest, Medline, Cochrane, Mosby's Index, Joanna Briggs Institute (JBI), and Scopus. Twenty-six (26) research papers published between 2000 and 2014 have met the selection criteria of this review. The key themes identified include; 1) ambiguity in definition of mature age and academic success, 2) age and academic success, 3) intrinsic factors (life experiences, emotional intelligence, and motivation and volition), and 4) extrinsic factors (peer, academic and family support; and learning style, components of the modules and mode of delivery). Current literature provides evidence that mature age nursing students perform at a higher level within the methodological issues discussed in this paper. Future research is warranted to advance the understanding of the complex relationship between extrinsic and intrinsic factors of mature age students and their academic success in higher education. Nursing educators will benefit from novel evidence, ideas and opportunities to explore and implement in nursing education.

  19. Quantitative evaluation of midpalatal suture maturation via fractal analysis

    PubMed Central

    Kwak, Kyoung Ho; Kim, Yong-Il; Kim, Yong-Deok

    2016-01-01

    Objective The purpose of this study was to determine whether the results of fractal analysis can be used as criteria for midpalatal suture maturation evaluation. Methods The study included 131 subjects aged over 18 years of age (range 18.1–53.4 years) who underwent cone-beam computed tomography. Skeletonized images of the midpalatal suture were obtained via image processing software and used to calculate fractal dimensions. Correlations between maturation stage and fractal dimensions were calculated using Spearman's correlation coefficient. Optimal fractal dimension cut-off values were determined using a receiver operating characteristic curve. Results The distribution of maturation stages of the midpalatal suture according to the cervical vertebrae maturation index was highly variable, and there was a strong negative correlation between maturation stage and fractal dimension (−0.623, p < 0.001). Fractal dimension was a statistically significant indicator of dichotomous results with regard to maturation stage (area under curve = 0.794, p < 0.001). A test in which fractal dimension was used to predict the resulting variable that splits maturation stages into ABC and D or E yielded an optimal fractal dimension cut-off value of 1.0235. Conclusions There was a strong negative correlation between fractal dimension and midpalatal suture maturation. Fractal analysis is an objective quantitative method, and therefore we suggest that it may be useful for the evaluation of midpalatal suture maturation. PMID:27668195

  20. Ovarian follicle maturation and ovulation: An integrated perspective

    USGS Publications Warehouse

    Patino, R.; Thomas, P.; Yoshizaki, G.

    2003-01-01

    Numerous studies with teleosts have addressed the regulation and mechanisms of oocyte maturation, but largely at the exclusion of ovulation. A smaller but still considerable number of studies have focused on ovulation, and ignored maturation. Consequently, little is known about the mechanistic linkages between these two events. New information is presented here indicating that luteinizing hormone regulates the acquisition not only of oocyte maturational competence, but also ovulatory competence. The thesis is presented that maturation and ovulation are closely integrated and overlapping events that are best viewed conceptually and experimentally as parts of a functional whole. ?? 2004 Kluwer Academic Publishers.

  1. Report to the administrator by the NASA Aerospace Safety Advisory Panel on the Skylab program. Volume 2: Program implementation and maturity. [systems management evaluation and design analysis

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Results of the design and manufacturing reviews on the maturity of the Skylab modules are presented along with results of investigations on the scope of the cluster risk assessment efforts. The technical management system and its capability to assess and resolve problems are studied.

  2. Lunar Module Ascent Stage

    NASA Technical Reports Server (NTRS)

    1969-01-01

    The Lunar Module 'Spider' ascent stage is photographed from the Command/Service Module on the fifth day of the Apollo 9 earth-orbital mission. The Lunar Module's descent stage had already been jettisoned.

  3. Wide deviation phase modulator

    NASA Technical Reports Server (NTRS)

    Couch, R. H.; Hearn, C. P.; Wilson, L. R.

    1974-01-01

    Modulator produces phase-modulated waveform having high modulating linearity. Technique is inherently wideband with respect to carrier frequency and can operate over decade carrier frequency range without adjustments. Circuit performance is both mathematically predictable and highly reproducible.

  4. MATURATION OF FIRING PATTERN IN CHICK VESTIBULAR NUCLEUS NEURONS

    PubMed Central

    SHAO, M.; HIRSCH, J. C.; PEUSNER, K. D.

    2007-01-01

    The principal cells of the chick tangential nucleus are vestibular nucleus neurons participating in the vestibuloocular and vestibulocollic reflexes. In birds and mammals, spontaneous and stimulus-evoked firing of action potentials is essential for vestibular nucleus neurons to generate mature vestibular reflex activity. The emergence of spike-firing pattern and the underlying ion channels were studied in morphologically-identified principal cells using whole-cell patch-clamp recordings from brain slices of late-term embryos (embryonic day 16) and hatchling chickens (hatching day 1 and hatching day 5). Spontaneous spike activity emerged around the perinatal period, since at embryonic day 16 none of the principal cells generated spontaneous action potentials. However, at hatching day 1, 50% of the cells fired spontaneously (range, 3 to 32 spikes/s), which depended on synaptic transmission in most cells. By hatching day 5, 80% of the principal cells could fire action potentials spontaneously (range, 5 to 80 spikes/s), and this activity was independent of synaptic transmission and showed faster kinetics than at hatching day 1. Repetitive firing in response to depolarizing pulses appeared in the principal cells starting around embryonic day 16, when < 20% of the neurons fired repetitively. However, almost 90% of the principal cells exhibited repetitive firing on depolarization at hatching day 1, and 100% by hatching day 5. From embryonic day 16 to hatching day 5, the gain for evoked spike firing increased almost 10-fold. At hatching day 5, a persistent sodium channel was essential for the generation of spontaneous spike activity, while a small conductance, calcium-dependent potassium current modulated both the spontaneous and evoked spike firing activity. Altogether, these in vitro studies showed that during the perinatal period, the principal cells switched from displaying no spontaneous spike activity at resting membrane potential and generating one spike on

  5. Maturation of firing pattern in chick vestibular nucleus neurons.

    PubMed

    Shao, M; Hirsch, J C; Peusner, K D

    2006-08-25

    The principal cells of the chick tangential nucleus are vestibular nucleus neurons participating in the vestibuloocular and vestibulocollic reflexes. In birds and mammals, spontaneous and stimulus-evoked firing of action potentials is essential for vestibular nucleus neurons to generate mature vestibular reflex activity. The emergence of spike-firing pattern and the underlying ion channels were studied in morphologically-identified principal cells using whole-cell patch-clamp recordings from brain slices of late-term embryos (embryonic day 16) and hatchling chickens (hatching day 1 and hatching day 5). Spontaneous spike activity emerged around the perinatal period, since at embryonic day 16 none of the principal cells generated spontaneous action potentials. However, at hatching day 1, 50% of the cells fired spontaneously (range, 3 to 32 spikes/s), which depended on synaptic transmission in most cells. By hatching day 5, 80% of the principal cells could fire action potentials spontaneously (range, 5 to 80 spikes/s), and this activity was independent of synaptic transmission and showed faster kinetics than at hatching day 1. Repetitive firing in response to depolarizing pulses appeared in the principal cells starting around embryonic day 16, when <20% of the neurons fired repetitively. However, almost 90% of the principal cells exhibited repetitive firing on depolarization at hatching day 1, and 100% by hatching day 5. From embryonic day 16 to hatching day 5, the gain for evoked spike firing increased almost 10-fold. At hatching day 5, a persistent sodium channel was essential for the generation of spontaneous spike activity, while a small conductance, calcium-dependent potassium current modulated both the spontaneous and evoked spike firing activity. Altogether, these in vitro studies showed that during the perinatal period, the principal cells switched from displaying no spontaneous spike activity at resting membrane potential and generating one spike on

  6. Clofazimine modulates the expression of lipid metabolism proteins in Mycobacterium leprae-infected macrophages.

    PubMed

    Degang, Yang; Akama, Takeshi; Hara, Takeshi; Tanigawa, Kazunari; Ishido, Yuko; Gidoh, Masaichi; Makino, Masahiko; Ishii, Norihisa; Suzuki, Koichi

    2012-01-01

    Mycobacterium leprae (M. leprae) lives and replicates within macrophages in a foamy, lipid-laden phagosome. The lipids provide essential nutrition for the mycobacteria, and M. leprae infection modulates expression of important host proteins related to lipid metabolism. Thus, M. leprae infection increases the expression of adipophilin/adipose differentiation-related protein (ADRP) and decreases hormone-sensitive lipase (HSL), facilitating the accumulation and maintenance of lipid-rich environments suitable for the intracellular survival of M. leprae. HSL levels are not detectable in skin smear specimens taken from leprosy patients, but re-appear shortly after multidrug therapy (MDT). This study examined the effect of MDT components on host lipid metabolism in vitro, and the outcome of rifampicin, dapsone and clofazimine treatment on ADRP and HSL expression in THP-1 cells. Clofazimine attenuated the mRNA and protein levels of ADRP in M. leprae-infected cells, while those of HSL were increased. Rifampicin and dapsone did not show any significant effects on ADRP and HSL expression levels. A transient increase of interferon (IFN)-β and IFN-γ mRNA was also observed in cells infected with M. leprae and treated with clofazimine. Lipid droplets accumulated by M. leprae-infection were significantly decreased 48 h after clofazimine treatment. Such effects were not evident in cells without M. leprae infection. In clinical samples, ADRP expression was decreased and HSL expression was increased after treatment. These results suggest that clofazimine modulates lipid metabolism in M. leprae-infected macrophages by modulating the expression of ADRP and HSL. It also induces IFN production in M. leprae-infected cells. The resultant decrease in lipid accumulation, increase in lipolysis, and activation of innate immunity may be some of the key actions of clofazimine.

  7. Osteocalcin Mediates Biomineralization during Osteogenic Maturation in Human Mesenchymal Stromal Cells

    PubMed Central

    Tsao, Yu-Tzu; Huang, Yi-Jeng; Wu, Hao-Hsiang; Liu, Yu-An; Liu, Yi-Shiuan; Lee, Oscar K.

    2017-01-01

    There is a growing interest in cell therapies using mesenchymal stromal cells (MSCs) for repairing bone defects. MSCs have the ability to differentiate into osteoprogenitors and osteoblasts as well as to form calcified bone matrix. However, the molecular mechanisms governing mineralization during osteogenic differentiation remain unclear. Non-collagenous proteins in the extracellular matrix are believed to control different aspects of the mineralization. Since osteocalcin is the most abundant non-collagenous bone matrix protein, the purpose of this study is to investigate the roles of osteocalcin in mineral species production during osteogenesis of MSCs. Using Raman spectroscopy, we found that the maturation of mineral species was affected by osteocalcin expression level. After osteocalcin was knocked down, the mineral species maturation was delayed and total hydroxyapatite was lower than the control group. In addition, the expression of osteogenic marker genes, including RUNX2, alkaline phosphatase, type I collagen, and osteonectin, was downregulated during osteogenic differentiation compared to the control group; whereas gene expression of osterix was upregulated after the knockdown. Together, osteocalcin plays an essential role for the maturation of mineral species and modulates osteogenic differentiation of MSCs. The results offer new insights into the enhancement of new bone formation, such as for the treatments of osteoporosis and fracture healing. PMID:28106724

  8. Maturation of polarization and luminance contrast sensitivities in cuttlefish (Sepia officinalis).

    PubMed

    Cartron, Lelia; Dickel, Ludovic; Shashar, Nadav; Darmaillacq, Anne-Sophie

    2013-06-01

    Polarization sensitivity is a characteristic of the visual system of cephalopods. It has been well documented in adult cuttlefish, which use polarization sensitivity in a large range of tasks such as communication, orientation and predation. Because cuttlefish do not benefit from parental care, their visual system (including the ability to detect motion) must be efficient from hatching to enable them to detect prey or predators. We studied the maturation and functionality of polarization sensitivity in newly hatched cuttlefish. In a first experiment, we examined the response of juvenile cuttlefish from hatching to the age of 1 month towards a moving, vertically oriented grating (contrasting and polarized stripes) using an optomotor response apparatus. Cuttlefish showed differences in maturation of polarization versus luminance contrast motion detection. In a second experiment, we examined the involvement of polarization information in prey preference and detection in cuttlefish of the same age. Cuttlefish preferentially chose not to attack transparent prey whose polarization contrast had been removed with a depolarizing filter. Performances of prey detection based on luminance contrast improved with age. Polarization contrast can help cuttlefish detect transparent prey. Our results suggest that polarization is not a simple modulation of luminance information, but rather that it is processed as a distinct channel of visual information. Both luminance and polarization sensitivity are functional, though not fully matured, in newly hatched cuttlefish and seem to help in prey detection.

  9. Prenatal androgens time neuroendocrine sexual maturation.

    PubMed

    Wood, R I; Ebling, F J; I'Anson, H; Bucholtz, D C; Yellon, S M; Foster, D L

    1991-05-01

    The present study determined whether exposure to gonadal steroids in utero dictates the postnatal control of gonadotropin secretion in the lamb. There is a marked sex difference in the timing of neuroendocrine sexual maturation in sheep; while male lambs undergo a reduction in sensitivity to inhibitory gonadal steroid feedback by 10 weeks of age, females remain hypersensitive until 30 weeks. The hypothesis was tested that prenatal androgens advance the time of the decrease in feedback sensitivity, and hence the pubertal increase in pulsatile gonadotropin secretion. Pregnant ewes were injected each week with 100 mg testosterone cypionate im from 30-90 days of gestation (term is approximately 150 days). Five female lambs were born with masculinized external genitalia (penis and scrotum). These females, together with eight androgenized males, eight control males, and eight control females, were gonadectomized at 2 weeks of age and implanted with a Silastic capsule of estradiol to produce a constant steroid feedback signal. Blood samples were collected twice weekly to monitor trends in LH secretion. For determination of LH pulse frequency, samples were collected frequently (every 12 min for 4 h) at various intervals between 5 and 32 weeks of age. In males, a sustained increase in LH from biweekly blood samples, indicative of reduced sensitivity to inhibitory steroid feedback, began at 10.1 +/- 1.4 weeks (mean +/- SE) of age in control males and at 5.4 +/- 0.1 weeks in androgenized males. By contrast, control females remained hypersensitive much longer as evidenced by the delay in the LH rise until 27.2 +/- 0.8 weeks. The response of the five androgenized females was intermediate; LH increased at 4, 7, 16, 20, and 21 weeks of age with an early increase of LH being associated with more pronounced masculinization of the genitalia. Patterns of pulsatile LH secretion reflected differences in serum LH measured from biweekly blood samples. For example, at 20 weeks of age

  10. Towards a Regolith Maturity Index for Howardites

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, David W.; Cartwright, J. A.; Herrin, J. S.; Johnson, K. N.

    2011-01-01

    The Dawn spacecraft has just arrived at asteroid 4 Vesta, parent of the howardite, eucrite and diogenite (HED) meteorites [1], to begin a yearlong surface study from orbit [2]. As Dawn will view a debris-covered surface, understanding the formation and mixing processes for the debris layer will strongly aid surface data interpretations. Howardites are polymict breccias mainly composed of clasts derived from basaltic (eucritic) and orthopy-roxenitic (diogenitic) parent materials [3]. Some howardites are poorly reworked (fragmental howardites) whilst others have been extensively gardened in an active regolith (regolithic howardites) [4]. The latter may represent an ancient, well-mixed regolith, whilst the former may be from more recent ejecta deposits [4]. Due to environmental differences, regolith development on Vesta differs in detail from that on the Moon [4-6]. We have been developing petrological criteria to apply to howardite thin sections to determine their relative regolithic maturity, which we are fine-tuning with comparison to noble gas data [7, 8]. Whilst we previously emphasized the abundance of reworked clasts (fragmental and impact-melt breccia clasts), this is an imperfect criterion: one howardite with abundant re-worked clasts (EET 99408) shows no evidence of solar wind Ne (SW-Ne), yet, two of our alleged fragmental howardites have clear SW-Ne signatures (LEW 85313, MET 00423) [7, 8]. We are now investigating the diversity in minor and trace element contents of low-Ca pyroxene clasts in howardites as a measure of regolith grade, and will begin analyses of such grains within reworked clasts. Our hypothesis is that regolithic howardites (and the breccia clasts they contain) will show greater diversity because they sampled more diverse diogenitic plutons than fragmental howardites, which formed from ejecta from only a few impacts [e.g. 4]. Our initial LA-ICP-MS work showed ranges in trace element diversity in low-Ca pyroxenes (estimated from the standard

  11. Direct Type I IFN but Not MDA5/TLR3 Activation of Dendritic Cells Is Required for Maturation and Metabolic Shift to Glycolysis after Poly IC Stimulation

    PubMed Central

    Haddad, Elias; Wood, Elizabeth G.; Longhi, M. Paula

    2014-01-01

    Type I interferons (IFNs) play an important role in direct antiviral defense as well as linking the innate and adaptive immune responses. On dendritic cells (DCs), IFNs facilitate their activation and contribute to CD8+ and CD4+ T cell priming. However, the precise molecular mechanism by which IFNs regulate maturation and immunogenicity of DCs in vivo has not been studied in depth. Here we show that, after in vivo stimulation with the TLR ligand poly IC, IFNs dominate transcriptional changes in DCs. In contrast to direct TLR3/mda5 signaling, IFNs are required for upregulation of all pathways associated with DC immunogenicity. In addition, metabolic pathways, particularly the switch from oxidative phosphorylation to glycolysis, are also regulated by IFNs and required for DC maturation. These data provide evidence for a metabolic reprogramming concomitant with DC maturation and offer a novel mechanism by which IFNs modulate DC maturation. PMID:24409099

  12. Modulation of lymphopoiesis

    SciTech Connect

    Rosse, C.

    1990-01-01

    Ongoing experiments contribute to the four specific aims in our current 3-year project period studying lymphopoiesis using CE mammary adenocarcinoma (CE maca) mice. Specific Aim 1: Function of Bone Marrow Stroma in CE Maca Bearing Mice. We have concluded that bone marrow stromal cells from tumor bearing animals are as effective as bone marrow stromal cells from normal animals at supporting B lymphopoiesis in culture. If stromal cell disfunction occurs in tumor bearing animals, the effect is not long lasting. Specific Aim 2: Factors Elaborated by CE Maca. Conditioned medium from CE maca cultures induces bone resorbing activity in bone organ cultures. We have identified a 32 kDa protein that meets the criteria for an osteoclast specific growth factor in this medium. However, we have also found that even though an osteoclast specific growth factor exists, a growth factor whose primary targets are granulocyte precursors will also stimulate osteoclast activity. Specific Aim 3: In Vitro Systems for Investigating Modulation of NK Lymphopoiesis by CE Maca. CE maca is shown to inhibit NK all production as well as B all production. In the course of the these experiments, we have established conditions for enriching NK precursors and have established a prototype long term bone marrow culture system which shows NK cell production. Specific Aim 4: Relationship Between Myclogenic and Intrathymic T Cell Precursors. There is evidence for a stream of T all maturation in both host (or intrathymic) cells and non-host (both hematogenous and intrathymic) cells. If thymic atrophy is induced by cortisone (a depopulation equivalent to that caused by 1000 rad) our data conclusively show thymic recovery is effected almost exclusively by intrathymic cells. This assigns a much greater importance to intrathymic T all progenitors in the maintenance of T cell production in the thymus than has been hitherto recognized. (MHB)

  13. Xanthohumol impairs autophagosome maturation through direct inhibition of valosin-containing protein.

    PubMed

    Sasazawa, Yukiko; Kanagaki, Shuhei; Tashiro, Etsu; Nogawa, Toshihiko; Muroi, Makoto; Kondoh, Yasumitsu; Osada, Hiroyuki; Imoto, Masaya

    2012-05-18

    Autophagy is a bulk, nonspecific protein degradation pathway that is involved in the pathogenesis of cancer and neurodegenerative disease. Here, we observed that xanthohumol (XN), a prenylated chalcone present in hops (Humulus lupulus L.) and beer, modulates autophagy. By using XN-immobilized beads, valosin-containing protein (VCP) was identified as a XN-binding protein. VCP has been reported to be an essential protein for autophagosome maturation. Using an in vitro pull down assay, we showed that XN bound directly to the N domain, which is known to mediate cofactor and substrate binding to VCP. These data indicated that XN inhibited the function of VCP, thereby allowing the impairment of autophagosome maturation and resulting in the accumulation of microtubule-associated protein 1 light chain 3-II (LC3-II). This is the first report demonstrating XN as a VCP inhibitor that binds directly to the N domain of VCP. Our finding that XN bound to and inactivated VCP not only reveals the molecular mechanism of XN-modulated autophagy but may also explain how XN exhibits various biological activities that have been reported previously.

  14. Smart Grid Interoperability Maturity Model Beta Version

    SciTech Connect

    Widergren, Steven E.; Drummond, R.; Giroti, Tony; Houseman, Doug; Knight, Mark; Levinson, Alex; longcore, Wayne; Lowe, Randy; Mater, J.; Oliver, Terry V.; Slack, Phil; Tolk, Andreas; Montgomery, Austin

    2011-12-02

    The GridWise Architecture Council was formed by the U.S. Department of Energy to promote and enable interoperability among the many entities that interact with the electric power system. This balanced team of industry representatives proposes principles for the development of interoperability concepts and standards. The Council provides industry guidance and tools that make it an available resource for smart grid implementations. In the spirit of advancing interoperability of an ecosystem of smart grid devices and systems, this document presents a model for evaluating the maturity of the artifacts and processes that specify the agreement of parties to collaborate across an information exchange interface. You are expected to have a solid understanding of large, complex system integration concepts and experience in dealing with software component interoperation. Those without this technical background should read the Executive Summary for a description of the purpose and contents of the document. Other documents, such as checklists, guides, and whitepapers, exist for targeted purposes and audiences. Please see the www.gridwiseac.org website for more products of the Council that may be of interest to you.

  15. Arnold Gesell and the maturation controversy.

    PubMed

    Dalton, Thomas C

    2005-01-01

    This article examines the work of Arnold Lucius Gesell and argues that he not only paved the way for contemporary research in motor development, but that he and colleagues anticipated fundamental issues about growth that must be addressed by psychologists and neuroscientists who are committed to the advancement of developmental science. Arnold Lucius Gesell was a pioneer in developmental psychology when the field was in its infancy. He worked diligently for the rights of physically and mentally handicapped children to receive special education that would enable them to find gainful employment. Gesell's writings in books and popular magazines increased public awareness of and support for preschool education and better foster care for orphans. Despite these achievements, many of his successors have questioned his views about infant development. Developmental psychologists have criticized Gesell for proposing a stage theory of infant growth that has fallen into disfavor among contemporary researchers. His conception of development as a maturational process has been challenged for allegedly reducing complex behavioral, perceptual, and learning processes to genetic factors. The author rejects this overly simplistic interpretation and contends that Gesell's work continues to stand the test of time.

  16. Potassium transport in the maturing kidney.

    PubMed

    Gurkan, Sevgi; Estilo, Genevieve K; Wei, Yuan; Satlin, Lisa M

    2007-07-01

    The distal nephron and colon are the primary sites of regulation of potassium (K(+)) homeostasis, responsible for maintaining a zero balance in adults and net positive balance in growing infants and children. Distal nephron segments can either secrete or reabsorb K(+) depending on the metabolic needs of the organism. In the healthy adult kidney, K(+) secretion predominates over K(+) absorption. Baseline K(+) secretion occurs via the apical low-conductance secretory K(+) (SK) channel, whereas the maxi-K channel mediates flow-stimulated net urinary K(+) secretion. The K(+) retention characteristic of the neonatal kidney appears to be due not only to the absence of apical secretory K(+) channels in the distal nephron but also to a predominance of apical H-K-adenosine triphosphatase (ATPase), which presumably mediates K(+) absorption. Both luminal and peritubular factors regulate the balance between K(+) secretion and absorption. Perturbation in any of these factors can lead to K(+) imbalance. In turn, these factors may serve as effective targets for the treatment of both hyper-and hypokalemia. The purpose of this review is to present an overview of recent advances in our understanding of mechanisms of K(+) transport in the maturing kidney.

  17. Deficits in Sialylation Impair Podocyte Maturation

    PubMed Central

    Weinhold, Birgit; Sellmeier, Melanie; Schaper, Wiebke; Blume, Linda; Philippens, Brigitte; Kats, Elina; Bernard, Ulrike; Galuska, Sebastian P.; Geyer, Hildegard; Geyer, Rudolf; Worthmann, Kirstin; Schiffer, Mario; Groos, Stephanie; Gerardy-Schahn, Rita

    2012-01-01

    The role of sialylation in kidney biology is not fully understood. The synthesis of sialoglycoconjugates, which form the outermost structures of animal cells, requires CMP-sialic acid, which is a product of the nuclear enzyme CMAS. We used a knock-in strategy to create a mouse with point mutations in the canonical nuclear localization signal of CMAS, which relocated the enzyme to the cytoplasm of transfected cells without affecting its activity. Although insufficient to prevent nuclear entry in mice, the mutation led to a drastically reduced concentration of nuclear-expressed enzyme. Mice homozygous for the mutation died from kidney failure within 72 hours after birth. The Cmasnls mouse exhibited podocyte foot process effacement, absence of slit diaphragms, and massive proteinuria, recapitulating features of nephrin-knockout mice and of patients with Finnish-type congenital nephrotic syndrome. Although the Cmasnls mouse displayed normal sialylation in all organs including kidney, a critical shortage of CMP-sialic acid prevented sialylation of nephrin and podocalyxin in the maturing podocyte where it is required during the formation of foot processes. Accordingly, the sialylation defects progressed with time and paralleled the morphologic changes. In summary, sialylation is critical during the development of the glomerular filtration barrier and required for the proper function of nephrin. Whether altered sialylation impairs nephrin function in human disease requires further study. PMID:22745475

  18. Optimum harvest maturity for Leymus chinensis seed

    PubMed Central

    Lin, Jixiang; Wang, Yingnan; Qi, Mingming; Li, Xiaoyu; Yang, Chunxue; Wang, Yongcui

    2016-01-01

    ABSTRACT Timely harvest is critical to achieve maximum seed viability and vigour in agricultural production. However, little information exists concerning how to reap the best quality seeds of Leymus chinensis, which is the dominant and most promising grass species in the Songnen Grassland of Northern China. The objective of this study was to investigate and evaluate possible quality indices of the seeds at different days after peak anthesis. Seed quality at different development stages was assessed by the colours of the seed and lemmas, seed weight, moisture content, electrical conductivity of seed leachate and germination indices. Two consecutive years of experimental results showed that the maximum seed quality was recorded at 39 days after peak anthesis. At this date, the colours of the seed and lemmas reached heavy brown and yellow, respectively. The seed weight was highest and the moisture content and the electrical conductivity of seed leachate were lowest. In addition, the seed also reached its maximum germination percentage and energy at this stage, determined using a standard germination test (SGT) and accelerated ageing test (AAT). Thus, Leymus chinensis can be harvested at 39 days after peak anthesis based on the changes in parameters. Colour identification can be used as an additional indicator to provide a more rapid and reliable measure of optimum seed maturity; approximately 10 days after the colour of the lemmas reached yellow and the colour of the seed reached heavy brown, the seed of this species was suitable for harvest. PMID:27170257

  19. Stretched Lens Array Squarerigger (SLASR) Technology Maturation

    NASA Technical Reports Server (NTRS)

    O'Neill, Mark; McDanal, A.J.; Howell, Joe; Lollar, Louis; Carrington, Connie; Hoppe, David; Piszczor, Michael; Suszuki, Nantel; Eskenazi, Michael; Aiken, Dan; Fulton, Michael; Brandhorst, Henry; Schuller, Michael

    2007-01-01

    Since April 2005, our team has been underway on a competitively awarded program sponsored by NASA s Exploration Systems Mission Directorate to develop, refine, and mature the unique solar array technology known as Stretched Lens Array SquareRigger (SLASR). SLASR offers an unprecedented portfolio of performance metrics, SLASR offers an unprecedented portfolio of performance metrics, including the following: Areal Power Density = 300 W/m2 (2005) - 400 W/m2 (2008 Target) Specific Power = 300 W/kg (2005) - 500 W/kg (2008 Target) for a Full 100 kW Solar Array Stowed Power = 80 kW/cu m (2005) - 120 kW/m3 (2008 Target) for a Full 100 kW Solar Array Scalable Array Capacity = 100 s of W s to 100 s of kW s Super-Insulated Small Cell Circuit = High-Voltage (300-600 V) Operation at Low Mass Penalty Super-Shielded Small Cell Circuit = Excellent Radiation Hardness at Low Mass Penalty 85% Cell Area Savings = 75% Lower Array Cost per Watt than One-Sun Array Modular, Scalable, & Mass-Producible at MW s per Year Using Existing Processes and Capacities

  20. WNT signaling in neuronal maturation and synaptogenesis

    PubMed Central

    Rosso, Silvana B.; Inestrosa, Nibaldo C.

    2013-01-01

    The Wnt signaling pathway plays a role in the development of the central nervous system and growing evidence indicates that Wnts also regulates the structure and function of the adult nervous system. Wnt components are key regulators of a variety of developmental processes, including embryonic patterning, cell specification, and cell polarity. In the nervous system, Wnt signaling also regulates the formation and function of neuronal circuits by controlling neuronal differentiation, axon outgrowth and guidance, dendrite development, synaptic function, and neuronal plasticity. Wnt factors can signal through three very well characterized cascades: canonical or β-catenin pathway, planar cell polarity pathway and calcium pathway that control different processes. However, divergent downstream cascades have been identified to control neuronal morphogenesis. In the nervous system, the expression of Wnt proteins is a highly controlled process. In addition, deregulation of Wnt signaling has been associated with neurodegenerative diseases. Here, we will review different aspects of neuronal and dendrite maturation, including spinogenesis and synaptogenesis. Finally, the role of Wnt pathway components on Alzheimer’s disease will be revised. PMID:23847469

  1. Low dose naltrexone (LDN) enhances maturation of bone marrow dendritic cells (BMDCs).

    PubMed

    Meng, Jingjuan; Meng, Yiming; Plotnikoff, Nicholas P; Youkilis, Gene; Griffin, Noreen; Shan, Fengping

    2013-12-01

    It has been demonstrated previously that immune cell activation and proliferation were sensitive to the effects of naltrexone, a non-peptidic δ-opioid receptor selective antagonist and opioid receptors on BMDCs have been detected [1]. However, there is little prior data published on naltrexone and DCs. Therefore, we hypothesized that LDN could exert modulating effect on BMDCs. In present study, we studied influence of LDN on both phenotypic and functional maturation of BMDCs. Changes of BMDC post-treatment with LDN were evaluated using conventional light microscope and transmission electron microscopy (TEM); flow cytometry(FCM); cytochemistry; acid phosphatase activity(ACP) test; FITC-dextran bio-assay; mixed lymphocytes and enzyme-linked immunosorbent assay (ELISA). We have found that LDN enhances maturation of BMDCs as evidenced by 1) up-regulating the expression of MHC II, CD40, CD83, CD80 and CD86 molecules on BMDCs; 2) down-regulating the rates of pinocytosis and phagocytosis accompanied by the results of decreased ACP, and FITC-dextran bio-assay; 3) mounting potential of BMDCs to drive T cell; and 4) inducing secretion of higher levels of IL-12 and TNF-α. It is therefore concluded that LDN can efficiently promote the maturation of BMDCs via precise modulation inside and outside BMDCs. Our study has provided meaningful mode of action on the role of LDN in immunoregulation, and rationale on future application of LDN for enhancing host immunity in cancer therapy and potent use in the design of DC-based vaccines for a number of diseases.

  2. Novel maturity parameters for mature to over-mature source rocks and oils based on the distribution of phenanthrene series compounds.

    PubMed

    Wang, Zixiang; Wang, Yongli; Wu, Baoxiang; Wang, Gen; Sun, Zepeng; Xu, Liang; Zhu, Shenzhen; Sun, Lina; Wei, Zhifu

    2016-03-01

    Pyrolysis experiments of a low-mature bitumen sample originated from Cambrian was conducted in gold capsules. Abundance and distribution of phenanthrene series compounds in pyrolysis products were measured by GC-MS to investigate their changes with thermal maturity. Several maturity parameters based on the distribution of phenanthrene series compounds have been discussed. The results indicate that the distribution changes of phenanthrene series compounds are complex, and cannot be explained by individual reaction process during thermal evolution. The dealkylation cannot explain the increase of phenanthrene within the EasyRo range of 0.9% ∼ 2.1%. Adding of phenanthrene into maturity parameters based on the methylphenanthrene isomerization is unreasonable, even though MPI 1 and MPI 2 could be used to some extent. Two additional novel and an optimized maturation parameters based on the distribution of phenanthrene series compounds are proposed and their relationships to EasyRo% (x) are established: log(MPs/P) = 0.19x + 0.08 (0.9% < EasyRo% < 2.1%); log(MPs/P) = 0.64x - 0.86 (2.1% < EasyRo% < 3.4%); log(DMPs/TMPs) = 0.71x - 0.55 (0.9% < EasyRo% < 3.4%); log(MTR) = 0.84x - 0.75 (0.9% < EasyRo% < 3.4%). These significant positive correlations are strong argument for using log(MPs/P), log(DMPs/TMPs) and log(MTR) as maturity parameters, especially for mature to over-mature source rocks.

  3. Thyroid hormone, neural tissue and mood modulation.

    PubMed

    Bauer, M; Whybrow, P C

    2001-04-01

    The successful treatment of affective disorders with thyroid hormone exemplifies the suggested inter-relationship between endocrine and neuronal systems in these disorders. Thyroid hormones have a profound influence on behaviour and appear to be capable of modulating the phenotypic expression of major affective illness. Specifically, there is good evidence that triiodothyronine (T3) may accelerate the antidepressant response to tricylic antidepressants, and some studies suggest that T3 may augment the therapeutic response to antidepressants in refractory depressed patients. Open studies have also indicated that adjunctive supraphysiological doses of thyroxine (T4) can ameliorate depressive symptomatology and help stabilize the long-term course of illness in bipolar and unipolar patients, especially women refractory to standard medications. Despite acceptance of the essential role of thyroid hormone on brain maturation and differentiation, and the clinical and therapeutic observations in association with mood disorders, the molecular action that may underlie the mood-modulating properties of thyroid hormone in the adult brain has only recently become the focus of research. The identification of nuclear T3 receptors, the region-specific expression of deiodinase isoenzymes and the molecular analyses of thyroid-responsive genes in the adult brain have provided the biological bases for a better understanding of thyroid hormone action in mature neurons. Also the influence of thyroid hormones on the putative neurotransmitter systems that regulate mood and behaviour, serotonin and norepinephrine, may be helpful in explaining their mood-modulating effects.

  4. Ballasted photovoltaic module and module arrays

    DOEpatents

    Botkin, Jonathan [El Cerrito, CA; Graves, Simon [Berkeley, CA; Danning, Matt [Oakland, CA

    2011-11-29

    A photovoltaic (PV) module assembly including a PV module and a ballast tray. The PV module includes a PV device and a frame. A PV laminate is assembled to the frame, and the frame includes an arm. The ballast tray is adapted for containing ballast and is removably associated with the PV module in a ballasting state where the tray is vertically under the PV laminate and vertically over the arm to impede overt displacement of the PV module. The PV module assembly can be installed to a flat commercial rooftop, with the PV module and the ballast tray both resting upon the rooftop. In some embodiments, the ballasting state includes corresponding surfaces of the arm and the tray being spaced from one another under normal (low or no wind) conditions, such that the frame is not continuously subjected to a weight of the tray.

  5. The Vocational Maturity of Inner-City Narcotic Addicts

    ERIC Educational Resources Information Center

    Powers, Robert J.

    1974-01-01

    The maturity of vocational attitudes of 103 narcotic addicts from New York City and of 46 of their peers was assessed. Comparison between scores of the addicts and their peers showed the former to have significantly lower maturity of vocational attitudes. (Author)

  6. Noninvasive maturity detection of citrus with machine vision

    NASA Astrophysics Data System (ADS)

    Ying, Yibin; Xu, Zhenggang; Fu, Xiaping; Liu, Yande

    2004-03-01

    A computer vision system was established to explore a method for citrus maturity detection. The surface color information and the ratio of total soluble solid to titratable acid (TSS/TA) were used as maturity indexes of citrus. The spectral reflectance properties with different color were measured by UV-240 ultraviolet and visible spectrophotometer. The biggest discrepancy of gray levels between citrus pixels and background pixels was in blue component image by image background segmentation. Dynamic threshold method for background segmentation had best result in blue component image. Methods for citrus image color description were studied. The citrus spectral reflectance experiments showed that green surface and saffron surface of citrus were of highest spectral reflectance at the wavelength of 700nm, the difference between them reached to maximum, about 53%, and the image acquired at this wavelength was of more color information for maturity detection. A triple-layer feed forward network was established to map citrus maturity from the hue frequency sequence by the mean of artificial neural network. After training, the network mapper was used to detect the maturity of the test sample set, which was composed of 252 Weizhang citrus with different maturity. The identification accuracy of mature citrus reached 79.1%, that of immature citrus was 63.6%, and the mean identification accuracy was 77.8%. This study suggested that it is feasible to detect citrus maturity non-invasively by using the computer vision system and hue frequency sequence method.

  7. Cultural Relativity in the Conceptualization of Career Maturity.

    ERIC Educational Resources Information Center

    Hardin, Erin E.; Leong, Frederick T. L.; Osipow, Samuel H.

    2001-01-01

    Asian Americans (n=182) and European Americans (n=235) completed Crites Career Maturity Inventory and the Self-Construal Scale; Asian Americans also completed an acculturation scale. Asian Americans exhibited less mature career choices; highly acculturated Asian Americans and those with lower interdependent self-construal were similar to European…

  8. Spiritual Maturation and Religious Behaviors in Christian University Students

    ERIC Educational Resources Information Center

    Welch, Ronald D.; Mellberg, Kimberlee

    2008-01-01

    Spiritual maturation processes of internalization and questing were assessed at a Christian university to determine their relationship to year in school and certain religious behaviors. This was a first step toward the development of a new model of Christian higher education that will intentionally facilitate spiritual maturation. A group of 179…

  9. Debt-maturity structures should match risk preferences.

    PubMed

    Gapenski, L C

    1999-12-01

    Key to any debt-maturity matching strategy is financing assets with the appropriate debt structure. Financial managers need to establish an optimal capital structure and then choose the best maturity-matching structure for their debt. Two maturity-matching strategies that are available to healthcare financial managers are the accounting approach and the finance approach. The accounting approach, which defines asset maturities as current or fixed, is a riskier financing strategy than the finance approach, which defines asset maturities as permanent or temporary. The added risk occurs because of the accounting approach's heavy reliance on short-term debt. The accounting approach offers the potential for lower costs at the expense of higher risk. Healthcare financial managers who believe the financing function should support the organization's operations without adding undue risk should use the finance approach to maturity matching. Asset maturities in those organizations then should be considered permanent or temporary rather than current or fixed, and the debt-maturity structure should reflect this.

  10. Assessment of Career Maturity in Transdisciplinary Vocational Assessment.

    ERIC Educational Resources Information Center

    Ohler, Denise L.; Levinson, Edward M.

    Since career development extends through the life span, career assessment may be helpful to individuals of all ages. This paper explains the theoretical bases for career maturity and provides definitions and correlates of the construct of career maturity. School psychologists, who typically work with students-at-risk academically and socially,…

  11. Old Dogs, New Tricks: Training Mature-Aged Manufacturing Workers

    ERIC Educational Resources Information Center

    Smith, Erica; Smith, Andrew; Smith, Chris Selby

    2010-01-01

    Purpose: This paper aims to examine the employment and training of mature-aged workers, so that suggestions for improving training for mature-aged workers may be offered. Design/methodology/approach: Six expert interviews were carried out by telephone, and three case studies involving company site visits were completed. Each company case study…

  12. Chemical Interruption of Flowering to Improve Harvested Peanut Maturity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peanut (Arachis hypogaea) is a botanically indeterminate plant where flowering, fruit initiation, and pod maturity occurs over an extended time period during the growing season. As a result, the maturity and size of individual peanut pods varies considerably at harvest. Immature kernels that meet co...

  13. Predicting Two Components of Career Maturity in School Based Adolescents.

    ERIC Educational Resources Information Center

    Creed, Peter A.; Patton, Wendy A.

    2003-01-01

    Multiple regression analyses of data on career maturity, work commitment, work values, self-efficacy, age, and career decidedness were conducted for 367 Australian students in grades 8-12. Chief predictors of career maturity attitudes were age, gender, and career certainty. Commitment and career indecision were the main predictors of career…

  14. Tomato seeds maturity detection system based on chlorophyll fluorescence

    NASA Astrophysics Data System (ADS)

    Li, Cuiling; Wang, Xiu; Meng, Zhijun

    2016-10-01

    Chlorophyll fluorescence intensity can be used as seed maturity and quality evaluation indicator. Chlorophyll fluorescence intensity of seed coats is tested to judge the level of chlorophyll content in seeds, and further to judge the maturity and quality of seeds. This research developed a detection system of tomato seeds maturity based on chlorophyll fluorescence spectrum technology, the system included an excitation light source unit, a fluorescent signal acquisition unit and a data processing unit. The excitation light source unit consisted of two high power LEDs, two radiators and two constant current power supplies, and it was designed to excite chlorophyll fluorescence of tomato seeds. The fluorescent signal acquisition unit was made up of a fluorescence spectrometer, an optical fiber, an optical fiber scaffolds and a narrowband filter. The data processing unit mainly included a computer. Tomato fruits of green ripe stage, discoloration stage, firm ripe stage and full ripe stage were harvested, and their seeds were collected directly. In this research, the developed tomato seeds maturity testing system was used to collect fluorescence spectrums of tomato seeds of different maturities. Principal component analysis (PCA) method was utilized to reduce the dimension of spectral data and extract principal components, and PCA was combined with linear discriminant analysis (LDA) to establish discriminant model of tomato seeds maturity, the discriminant accuracy was greater than 90%. Research results show that using chlorophyll fluorescence spectrum technology is feasible for seeds maturity detection, and the developed tomato seeds maturity testing system has high detection accuracy.

  15. Black-White Differences in Psychosocial Maturity: A Further Analysis.

    ERIC Educational Resources Information Center

    Greenberger, Ellen; Marini, Margaret Mooney

    Following up on an earlier study which found that blacks and whites differed significantly on a 54-item development scale designed to measure effective individual functioning, or "maturity," this report considers whether the content of the Psychosocial Maturity Scale (PSM) is biased in favor of white children and if this bias invalidates…

  16. Phenomenological Aspects of Psychosocial Maturity in Adolescence. Report No. 198.

    ERIC Educational Resources Information Center

    Josselson, Ruthellen; And Others

    Forty-one subjects who score at the high and low extremes of the Psychosocial Maturity (PSM) Inventory were intensively interviewed. These interview data were analyzed to contrast the phenomenological and psychodynamic forces in the lives of these subjects that influence their current state of psychosocial maturity. Case material is presented.…

  17. Junior High Career Maturity Activities. Report No. 33-A-57.

    ERIC Educational Resources Information Center

    Afdahl, Anne; And Others

    The activities in this curriculum guide are designed to facilitate self-evaluation, goal setting, and educator-student planning of junior high learning experiences relating to career maturity. It is suggested that the career maturity measurement activity worksheets can be included in the student's school record and used as a reference base for…

  18. Predicting Career Maturity Attitudes in Rural Economically Disadvantaged Youth.

    ERIC Educational Resources Information Center

    Rojewski, Jay W.

    1994-01-01

    Six predictor variables (gender, race, disadvantage, postsecondary plans, vocational education, career indecision) were 75% accurate in identifying career maturity and immaturity among 90 economically disadvantaged rural ninth graders. Career indecision and race were most important for career immaturity, race and disadvantage for career maturity.…

  19. Senior High Career Maturity Activities. Report No. 33-A-58.

    ERIC Educational Resources Information Center

    Bauman, Virginia; And Others

    The activities in this curriculum guide are designed to facilitate self-evaluation, goal setting, and educator-student planning of learning experiences relating to career maturity. It is suggested that the career maturity measurement activity worksheets can be included in the student's school record and used as a reference base for future…

  20. Career Maturity of Ninth Grade Pupils: Real or Imaginary?

    ERIC Educational Resources Information Center

    Westbrook, Bert W.; Cutts, Catherine C.

    The purpose of this study was to investigate the construct validity of the Career Maturity Inventory with ninth grade pupils. To demonstrate the construct validity it must be shown that the Career Maturity Inventory correlates highly with other variables with which it should theoretically correlate, and that it does not correlate with variables…

  1. Educational, Social, and Psychological Correlates of Vocational Maturity.

    ERIC Educational Resources Information Center

    Khan, Sar B.; Alvi, Sabir A.

    1983-01-01

    Investigated educational, social, and psychological correlates of vocational maturity in Ontario high school students (N=272). Analysis showed Career Maturity Inventory (CMI) scores were generally correlated with students' educational and occupational aspirations and parents' aspirations. Higher CMI scores were associated with higher self-esteem…

  2. Career Maturity in Relation to Differences in School Curriculum.

    ERIC Educational Resources Information Center

    Khan, Sar B.; Alvi, Sabir A.

    1985-01-01

    Examined differences in career maturity among four curriculum groups: academic, business, technical, and general. In Study I, administered Crites' Career Maturity Inventory to students in grades 9-12. In Study II, administered a specially developed measure of career development to students in grade 12. Results indicated that the academic group…

  3. Mature Students Speak Up: Career Exploration and the Working Alliance

    ERIC Educational Resources Information Center

    Pott, Terilyn

    2015-01-01

    This exploratory study was undertaken to learn more about how mature students perceive the career counselling process in a post-secondary institution. Through the use of critical incident technique this study examined how three mature students interpret their relationship between themselves and their counsellors. Significant factors identified as…

  4. Gender, Change and Identity: Mature Women Students in Universities.

    ERIC Educational Resources Information Center

    Merrill, Barbara

    This book examines women's lives, past and present, to understand experiences of mature women students in universities. Chapter 1 explores current research and literature on mature women students in adult and continuing education. Chapter 2 reflects on the value of sociology and particular theoretical approaches such as feminist sociology, action,…

  5. Chemical Interruption of Flowering to Improve Harvested Peanut Maturity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peanut (Arachis hypogaea) is a botanically indeterminate plant where flowering, fruit initiation, and pod maturity occurs over an extended time period during the growing season. As a result, the maturity and size of individual peanut pods varies considerably at harvest. Immature kernels that meet...

  6. Gene expression profiles of auxin metabolism in maturing apple fruit

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Variation exists among apple genotypes in fruit maturation and ripening patterns that influences at-harvest fruit firmness and postharvest storability. Based on the results from our previous large-scale transcriptome profiling on apple fruit maturation and well-documented auxin-ethylene crosstalk, t...

  7. Anaplasma marginale actively modulates vacuolar maturation during intracellular infection of its tick vector dermacentor andersoni

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tick-borne transmission of bacterial pathogens in the Order Rickettsiales is responsible for a diversity of infectious diseases, many of them severe, in both humans and animals. Transmission dynamics differ among these pathogens and are reflected in the pathogen-vector interaction. Anaplasma margina...

  8. Maternal age at maturation underpins contrasting behavior in offspring

    PubMed Central

    Robertsen, Grethe; Stewart, David C.; McKelvey, Simon; Armstrong, John D.; Metcalfe, Neil B.

    2016-01-01

    In species where parental care occurs primarily via the provisioning of eggs, older females tend to produce larger offspring that have better fitness prospects. Remarkably however, a relationship between age of mother and fitness of offspring has also been reported independently of effects on offspring size suggesting that there may be other factors at play. Here, using experimental matings between wild Atlantic salmon that differed in their age at sexual maturation, we demonstrate distinct size-independent variation in the behavior of their offspring that was related to the maturation age of the mother (but not the father). We found that when juvenile salmon were competing for feeding territories, offspring of early-maturing mothers were more aggressive than those of late-maturing mothers, but were out-competed for food by them. This is the first demonstration of a link between natural variation in parental age at maturation and variation in offspring behavior. PMID:27656083

  9. Affinity maturation of antibodies requires integrity of the adult thymus.

    PubMed

    AbuAttieh, Mouhammed; Bender, Diane; Liu, Esther; Wettstein, Peter; Platt, Jeffrey L; Cascalho, Marilia

    2012-02-01

    The generation of B-cell responses to proteins requires a functional thymus to produce CD4(+) T cells which helps in the activation and differentiation of B cells. Because the mature T-cell repertoire has abundant cells with the helper phenotype, one might predict that in mature individuals, the generation of B-cell memory would proceed independently of the thymus. Contrary to that prediction, we show here that the removal of the thymus after the establishment of the T-cell compartment or sham surgery without removal of the thymus impairs the affinity maturation of antibodies. Because removal or manipulation of the thymus did not decrease the frequency of mutation of the Ig variable heavy chain exons encoding antigen-specific antibodies, we conclude that the thymus controls affinity maturation of antibodies in the mature individual by facilitating the selection of B cells with high-affinity antibodies.

  10. The maturity of Nypa palm worm Namalycastis rhodochorde (Nereididae: Polychaeta)

    NASA Astrophysics Data System (ADS)

    Junardi, Anggraeni, Tjandra; Ridwan, Ahmad; Yuwono, Edy

    2014-03-01

    The Nypa Palm Worm Namalycastis rhodochorde has been used as bait for fishing and commercial species in Pontianak. Maturity is one important characteristic to learn the population dynamic and management. The Nypa Palm worm samples were collected from mangrove area in Kapuas Estuary, West Kalimantan. Fresh samples of gametes collected from the coelomic fluid were observed carefully under compound microscope for the initial determination of maturity. The presences of oocyte ≥120μm in diameter and lipid droplet are the indication of female maturity, while free swimming spermatozoon in the body fluid is the indication of male maturity. Morphologically, the maturity of N. rhodochorde was indicated by the change of body color, softer and fragile body, yet no modified chaetae and heteronereid form.

  11. Customer-Provider Strategic Alignment: A Maturity Model

    NASA Astrophysics Data System (ADS)

    Luftman, Jerry; Brown, Carol V.; Balaji, S.

    This chapter presents a new model for assessing the maturity of a ­customer-provider relationship from a collaborative service delivery perspective: the Customer-Provider Strategic Alignment Maturity (CPSAM) Model. This model builds on recent research for effectively managing the customer-provider relationship in IT service outsourcing contexts and a validated model for assessing alignment across internal IT service units and their business customers within the same organization. After reviewing relevant literature by service science and information systems researchers, the six overarching components of the maturity model are presented: value measurements, governance, partnership, communications, human resources and skills, and scope and architecture. A key assumption of the model is that all of the components need be addressed to assess and improve customer-provider alignment. Examples of specific metrics for measuring the maturity level of each component over the five levels of maturity are also presented.

  12. A comparative study of young and mature bovine cortical bone.

    PubMed

    Manilay, Zherrina; Novitskaya, Ekaterina; Sadovnikov, Ernest; McKittrick, Joanna

    2013-02-01

    The mechanical properties and microstructure of young and mature bovine femur bone were investigated by optical microscopy and compression testing in the longitudinal and transverse directions for untreated, deproteinized and demineralized cases. Optical microscopy revealed that mature bone has a more established and less porous microstructure compared to young bone. Mature bone was found to be stronger in both directions for the untreated and deproteinized cases. Mature untreated bone was also found to be stiffer and less tough compared to young bone in both directions. These results are related to the increase in mineralization of mature bone and significant microstructural differences. Young bone was found to be stronger in both directions for the demineralized case, which is attributed to alterations in the collagen network with age.

  13. Transient domain formation in membrane-bound organelles undergoing maturation

    NASA Astrophysics Data System (ADS)

    Dmitrieff, Serge; Sens, Pierre

    2013-12-01

    The membrane components of cellular organelles have been shown to segregate into domains as the result of biochemical maturation. We propose that the dynamical competition between maturation and lateral segregation of membrane components regulates domain formation. We study a two-component fluid membrane in which enzymatic reaction irreversibly converts one component into another and phase separation triggers the formation of transient membrane domains. The maximum domain size is shown to depend on the maturation rate as a power law similar to the one observed for domain growth with time in the absence of maturation, despite this time dependence not being verified in the case of irreversible maturation. This control of domain size by enzymatic activity could play a critical role in regulating exchange between organelles or within compartmentalized organelles such as the Golgi apparatus.

  14. Objectives and Design of the Hemodialysis Fistula Maturation Study

    PubMed Central

    Dember, Laura M.; Imrey, Peter B.; Beck, Gerald J.; Cheung, Alfred K.; Himmelfarb, Jonathan; Huber, Thomas S.; Kusek, John W.; Roy-Chaudhury, Prabir; Vazquez, Miguel A.; Alpers, Charles E.; Robbin, Michelle L.; Vita, Joseph A.; Greene, Tom; Gassman, Jennifer J.; Feldman, Harold I.

    2014-01-01

    Background A large proportion of newly created arteriovenous fistulas cannot be used for dialysis because they fail to mature adequately to support the hemodialysis blood circuit. The Hemodialysis Fistula Maturation (HFM) Study was designed to elucidate clinical and biological factors associated with fistula maturation outcomes. Study Design Multicenter prospective cohort study. Setting & Participants Approximately 600 patients undergoing creation of a new hemodialysis fistula will be enrolled at 7 centers in the United States and followed up for as long as 4 years. Predictors Clinical, anatomical, biological, and process-of-care attributes identified pre-operatively, intra-operatively, or post-operatively. Outcomes The primary outcome is unassisted clinical maturation defined as successful use of the fistula for dialysis for four weeks without any maturation-enhancing procedures. Secondary outcomes include assisted clinical maturation, ultrasound-based anatomical maturation, fistula procedures, fistula abandonment, and central venous catheter use. Measurements Pre-operative ultrasound arterial and venous mapping, flow-mediated and nitroglycerin-mediated brachial artery dilation, arterial pulse wave velocity, and venous distensibility; intra-operative vein tissue collection for histopathological and molecular analyses; post-operative ultrasounds at 1 day, 2 weeks, 6 weeks, and prior to fistula intervention and initial cannulation. Results Assuming complete data, no covariate adjustment, and unassisted clinical maturation of 50%, there will be 80% power to detect ORs of 1.83 and 1.61 for dichotomous predictor variables with exposure prevalences of 20% and 50%, respectively. Limitations Exclusion of two-stage transposition fistulas limits generalizability. The requirement for study visits may result in a cohort that is healthier than the overall population of patients undergoing fistula creation. Conclusions The HFM Study will be of sufficient size and scope to 1

  15. The neurochemical maturation of the rabbit cerebellum.

    PubMed Central

    Lossi, L; Ghidella, S; Marroni, P; Merighi, A

    1995-01-01

    The immunocytochemical distribution of several neuronal and glial antigens was investigated in the cerebellum of the developing and adult rabbit. Neurofilament positive neurons appeared at embryonic day (E) 25. Purkinje cells transiently expressed neurofilament polypeptides from postnatal day (P) 0 to 15. At later postnatal ages, staining was localised to the parallel fibres, the axonal arbors of the basket cells and fibres of the white matter. Neuron specific enolase (NSE) immunoreactivity was first detected at E25. At P0 Purkinje cells were positive and their staining intensity increased up to P25. From P30 to adulthood virtually all cells in the molecular and Purkinje cell layers were stained. Scattered PGP 9.5-immunoreactive neurons appeared in the cerebellar anlage at P25. Purkinje and Golgi cells were labelled by P0. Synaptophysin immunoreactivity was first observed at P0 in the form of a fine punctate reaction surrounding the perikarya and proximal dendrites of Purkinje cells. By P10, it became particularly intense within the cerebellar glomeruli of the granular layer. Neurons of the deep cerebellar nuclei expressed NSE and PGP 9.5 starting from E25. GFAP and S-100 immunoreactivities were first detected at P10. GFAP-immunopositive astrocytes progressively increased in number up to adulthood. S-100-immunoreactive glial cells were detected throughout the white and grey matter. Bergmann glial cells and their fibres were strongly immunoreactive. Vimentin positive glial cells and fibres were first observed at E15 and persisted up to adulthood. Double labelling experiments using a monoclonal antibody against the proliferating cell nuclear antigen (PCNA), a cyclin synthesised by mitotic cells, showed that neuronal and/or glial polypeptides are expressed only by fully differentiated postmitotic cells. These results indicate that major events in the neurochemical maturation of the rabbit cerebellum occur during the first month after birth, when the same pattern of

  16. Module utilization committee

    NASA Technical Reports Server (NTRS)

    Volkmer, K.; Praver, G.

    1984-01-01

    Photovoltaic collector modules were declared surplus to the needs of the U.S. Dept. of Energy. The Module Utilization Committee was formed to make appropriate disposition of the surplus modules on a national basis and to act as a broker for requests for these modules originating outside of the National Photovoltaics Program.

  17. Increasing the cAMP concentration during in vitro maturation of pig oocytes improves cumulus maturation and subsequent fertilization in vitro.

    PubMed

    Appeltant, R; Beek, J; Vandenberghe, L; Maes, D; Van Soom, A

    2015-02-01

    Porcine IVF faces various problems such as incomplete cytoplasmic maturation of the oocyte and polyspermy. Previous studies proved the importance of cAMP in regulating nuclear and cytoplasmic maturation of oocytes. This study investigated the effect of the cAMP-modulating agents 3-isobutyl-1-methylxanthine (IBMX) and dibutyryl cAMP sodium salt (dbcAMP) on several parameters during in vitro production of porcine embryos. First, we wanted to see if oocyte collection in IBMX could meiotically arrest oocytes and, as such, improve synchronization of nuclear and cytoplasmic maturation. To this end, cumulus-oocyte complexes (COCs) were collected from gilts in HEPES-buffered Tyrode balanced salt solution medium with 0.5-mM IBMX or without IBMX. At the end of oocyte collection, the effect of IBMX on chromatin configuration was evaluated. However, no differences could be observed in nuclear configuration between IBMX- and IBMX+ oocytes (P > 0.05). Second, we added dbcAMP during IVM to improve cytoplasmic maturation and evaluated cumulus expansion (lack of adhesion), a disintegrin and metalloproteinase with thrombospondin-like repeats (ADAMTS-1) levels in cumulus cells, fertilization, and blastocyst rates. Cumulus-oocyte complexes were matured in modified North Carolina State University medium 37 with or without 1-mM dbcAMP. Frozen-thawed, epididymal, boar spermatozoa were used for IVF. After IVF, presumed zygotes were cultured for 7 days in North Carolina State University medium 23. Penetration rate decreased in dbcAMP+ (57.3%) compared with dbcAMP- (67.8%), but the polyspermy rate also decreased (43.3% vs. 53.4%, respectively) leading to an increased normal fertilization rate (56.7% vs. 46.6%, respectively; P < 0.05). Only 7.2% of the COCs showed adhesion in dbcAMP+ which was lower than 15.7% in dbcAMP- (P < 0.05) probably because of an upregulation of the ADAMTS-1 protein by dbcAMP. When the adherent oocytes were removed during maturation, no difference could be

  18. On the Validity of the Psychosocial Maturity Inventory: An Examination of Psychosocial Maturity and Dogmatism. Report No. 203.

    ERIC Educational Resources Information Center

    Bond, Lloyd; And Others

    Form D of the Psychosocial Maturity (PSM) Inventory and the Rokeach Dogmatism Scale were administered to 325 10th grade students to test a predicted correlation between the Dogmatism Scale and the Change and Tolerance subscales of the PSM battery, and to examine the pattern of covariation between psychosocial maturity and dogmatism. A substantial…

  19. Almond brush module cutter

    SciTech Connect

    Zohns, M.A.; Jenkins, B.M.; Mehlschau, J.J.; Morrison, D.

    1983-06-01

    This paper addresses the design, construction, and evaluation of an almond brush module cutter. The module cutter is one link in a system which processes tree prunings for fuel and fiber. This system includes a modified cotton module builder, a module mover, the cutter, and a tub grinder. An economic analysis of the cutter is presented along with the problems involved in cutting brush modules.

  20. Haemoglobin polymorphism in Gadus morhua: Genotypic differences in maturing age and within-season gonad maturation

    NASA Astrophysics Data System (ADS)

    Mork, J.; Giskeödegård, R.; Sundnes, G.

    1983-09-01

    276 specimens of Atlantic cod ( Gadus morhua L.) were caught during spawning in a restricted area of the Trondheimsfjord, Norway, in April and May 1979. Genotypes at the polymorphic haemoglobin locus Hbl differed significantly with respect to mean age at maturation (in males) and mean gonadic development stage (in females). There was no indication of population mixing in the genotypic composition at Hbl or at any of the 4 polymorphic tissue enzyme loci investigated ( LDH-3, IDH-1, PGM, and PGI-1. The findings obtained were considered with regard to temperature-related differences in the functional properties of Hbl molecules, and genotypic differences in growth, age at maturation, and fishing mortality. At the present stage of investigation, the natural selection pattern seems directional and strong. However, the Hbl allele frequencies observed in cod from the examined areas reveal no detectable changes over a period of two decades (˜ 4 generations). The current pattern of commercial exploitation causes, through size selection, a modification of the rate of erosion of the inferior allele, but additional factors must be in force, which play a role in its current abundance in an evolutionary perspective. The observed Hbl genotypic differences in the exact within-season time for spawning might be one such factor. A potential sexual difference in genotypic fitness might be another, but this has yet to be confirmed. The apparent existence of considerable natural and artificial selection forces acting upon cod haemoglobin genotypes makes Hbl allele frequencies unreliable for use in population structure analyses.

  1. Maturing the minor, marginalizing the family: on the social construction of the mature minor.

    PubMed

    Barina, Rachelle; Bishop, Jeffrey P

    2013-06-01

    The doctrine of the mature minor began as an emergency exception to the rule of parental consent. Over time, the doctrine crept into cases that were non-emergent. In this essay, we show how the doctrine also developed in the context of the latter part of the 20th century, at the same time that the sexual revolution, the pill, and sexual liberation came to be seen as important symbols of female liberation--liberation that required that female minors be granted the status of a mature minor. To do so moves sexual morality out of the domain of the family, where it had always been situated, and into the domain of the state. We also show how a phenomenological account of the care of the body in the family conforms to the latest in neuroscientific understandings of adolescent brain development. The family attenuates the dependency of adolescents and provides an important social contextualization for the care of the body, including the inculcation of sexual mores in adolescence. We conclude that the drive to push sexual decision making as a matter of state concern further undermines the foundations of the moral meanings of sex and sexuality.

  2. Aberrant frontal lobe maturation in adolescents with fragile X syndrome is related to delayed cognitive maturation

    PubMed Central

    Bray, Signe; Hirt, Melissa; Jo, Booil; Hall, Scott S.; Lightbody, Amy A.; Walter, Elizabeth; Chen, Kelly; Patnaik, Swetapadma; Reiss, Allan L.

    2011-01-01

    Background Fragile X syndrome (FXS) is the most common known heritable cause of intellectual disability. Prior studies in FXS have observed a plateau in cognitive and adaptive behavioral development in early adolescence, suggesting that brain development in FXS may diverge from typical development during this period. Methods In this study, we examined adolescent brain development using structural magnetic resonance imaging data acquired from 59 individuals with FXS, and 83 typically developing (TD) controls aged 9 to 22, a subset of whom were followed-up longitudinally (1-5 years; TD:17, FXS:19). Regional volumes were modeled to obtain estimates of age-related change. Results We found that while structures such as the caudate showed consistent volume differences from controls across adolescence, prefrontal cortex gyri (PFC) showed significantly aberrant maturation. Furthermore, we found that PFC-related measures of cognitive functioning followed a similarly aberrant developmental trajectory in FXS. Conclusions Our findings suggest that aberrant maturation of the PFC during adolescence may contribute to persistent or increasing intellectual deficits in FXS. PMID:21802660

  3. Social Maturity and Executive Function Among Deaf Learners.

    PubMed

    Marschark, Marc; Kronenberger, William G; Rosica, Mark; Borgna, Georgianna; Convertino, Carol; Durkin, Andreana; Machmer, Elizabeth; Schmitz, Kathryn L

    2017-01-01

    Two experiments examined relations among social maturity, executive function, language, and cochlear implant (CI) use among deaf high school and college students. Experiment 1 revealed no differences between deaf CI users, deaf nonusers, and hearing college students in measures of social maturity. However, deaf students (both CI users and nonusers) reported significantly greater executive function (EF) difficulties in several domains, and EF was related to social maturity. Experiment 2 found that deaf CI users and nonusers in high school did not differ from each other in social maturity or EF, but individuals who relied on sign language reported significantly more immature behaviors than deaf peers who used spoken language. EF difficulties again were associated with social maturity. The present results indicate that EF and social maturity are interrelated, but those relations vary in different deaf subpopulations. As with academic achievement, CI use appears to have little long-term impact on EF or social maturity. Results are discussed in terms of their convergence with findings related to incidental learning and functioning in several domains.

  4. Synapse Maturation by Activity-Dependent Ectodomain Shedding of SIRPα

    PubMed Central

    Toth, Anna B.; Terauchi, Akiko; Zhang, Lily Y.; Johnson-Venkatesh, Erin M.; Larsen, David J.; Sutton, Michael A.; Umemori, Hisashi

    2013-01-01

    Formation of appropriate synaptic connections is critical for proper functioning of the brain. After initial synaptic differentiation, active synapses are stabilized by neural activity-dependent signals to establish functional synaptic connections. However, the molecular mechanisms underlying activity-dependent synapse maturation remain to be elucidated. Here we show that activity-dependent ectodomain shedding of SIRPα mediates presynaptic maturation. Two target-derived molecules, FGF22 and SIRPα, sequentially organize the glutamatergic presynaptic terminals during the initial synaptic differentiation and synapse maturation stages, respectively, in the mouse hippocampus. SIRPα drives presynaptic maturation in an activity-dependent fashion. Remarkably, neural activity cleaves the extracellular domain of SIRPα, and the shed ectodomain, in turn, promotes the maturation of the presynaptic terminal. This process involves CaM kinase, matrix metalloproteinases, and the presynaptic receptor CD47. Finally, SIRPα-dependent synapse maturation has significant impacts on synaptic function and plasticity. Thus, ectodomain shedding of SIRPα is an activity-dependent trans-synaptic mechanism for the maturation of functional synapses. PMID:24036914

  5. Maturation of recombinant hepatitis B virus surface antigen particles.

    PubMed

    Zhao, Qinjian; Wang, Yang; Freed, Daniel; Fu, Tong-Ming; Gimenez, Juan A; Sitrin, Robert D; Washabaugh, Michael W

    2006-01-01

    The major surface antigen of Hepatitis B virus (HBsAg) is a cysteine-rich, lipid-bound protein with 226 amino acids. Recombinant HBsAg (rHBsAg) with associated lipids can self-assemble into 22-nm immunogenic spherical particles, which are used in licensed Hepatitis B vaccines. Little is known about the structural evolvement or maturation upon assembly beyond an elevated level of disulfide formation. In this paper, we further characterized the maturation of HBsAg particles with respect to their degree of cross-linking, morphological changes, and changes in conformational flexibility. The lipid-containing rHBsAg particles undergo KSCN- and heat-induced maturation by formation of additional intra- and inter-molecular disulfide bonds. Direct measurements with atomic force microscopy (AFM) revealed morphological changes upon maturation through KSCN-induced and heat-/storage-incurred oxidative refolding. Particle uniformity and regularity was greatly improved, and protrusions formed by the protein subunits were more prominent on the surface of the mature particles. Decreased conformational flexibility in the mature rHBsAg particles was demonstrated by millisecond-scale unfolding kinetics in the presence of an environment-sensitive conformation probe. Both the accessible hydrophobic cavities under native conditions and the changeable hydrophobic cavities upon denaturant-induced unfolding showed substantial decrease upon maturation of the rHBsAg particles. These changes in the structural properties may be critical for the antigenicity and immuno-genicity of this widely-used vaccine component.

  6. Provisional bilateral symmetry in Xenopus eggs is established during maturation

    NASA Technical Reports Server (NTRS)

    Brown, E. E.; Margelot, K. M.; Danilchik, M. V.

    1994-01-01

    Dorsal-ventral patterning in the Xenopus egg becomes established midway through the first cell cycle during a 30 degree rotation of the subcortical yolk mass relative to the egg cortex. This 'rotation of symmetrisation' is microtubule dependent, and its direction is thought to be cued by the usually eccentric sperm centrosome. The fact that parthenogenetically activated eggs also undergo a directed rotation, despite the absence of a sperm centrosome, suggests that an endogenous asymmetry in the unfertilised egg supports the directed polymerisation of microtubules in the vegetal cortex, in the way that an eccentric sperm centrosome would in fertilised eggs. Consistent with this idea, we noticed that the maturation spot is usually located an average of more than 15 degrees from the geometric centre of the pigmented animal hemisphere. In parthenogenetically activated eggs, this eccentric maturation spot can be used to predict the direction of rotation. Although in most fertilised eggs the yolk mass rotates toward the sperm entry point (SEP) meridian, occasionally this relationship is perturbed significantly; in such eggs, the maturation spot is never on the same side of the egg as the SEP. In oocytes tilted 90 degrees from upright during maturation in vitro, the maturation spot developed 15 degrees or more from the centre of the pigmented hemisphere, always displaced towards the point on the equator that was up during maturation. This experimentally demonstrated lability is consistent with an off-axis oocyte orientation during oogenesis determining its eccentric maturation spot position, and, in turn, its endogenous rotational bias.

  7. Physical activity and biological maturation: a systematic review

    PubMed Central

    Bacil, Eliane Denise Araújo; Mazzardo, Oldemar; Rech, Cassiano Ricardo; Legnani, Rosimeide Francisco dos Santos; de Campos, Wagner

    2015-01-01

    OBJECTIVE: To analyze the association between physical activity (PA) and biological maturation in children and adolescents. DATA SOURCE: We performed a systematic review in April 2013 in the electronic databases of PubMed/MEDLINE, SportDiscus, Web of Science and LILACS without time restrictions. A total of 628 potentially relevant articles were identified and 10 met the inclusion criteria for this review: cross-sectional or longitudinal studies, published in Portuguese, English or Spanish, with schoolchildren aged 9-15 years old of both genders. DATA SYNTHESIS: Despite the heterogeneity of the studies, there was an inverse association between PA and biological maturation. PA decreases with increased biological and chronological age in both genders. Boys tend to be more physically active than girls; however, when controlling for biological age, the gender differences disappear. The association between PA and timing of maturation varies between the genders. Variation in the timing of biological maturation affects the tracking of PA in early adolescent girls. This review suggests that mediators (BMI, depression, low self-esteem, and concerns about body weight) can explain the association between PA and biological maturation. CONCLUSIONS: There is an association between PA and biological maturation. PA decreases with increasing biological age with no differences between genders. As for the timing of biological maturation, this association varies between genders. PMID:25583624

  8. Inference of Longevity-Related Genes from a Robust Coexpression Network of Seed Maturation Identifies Regulators Linking Seed Storability to Biotic Defense-Related Pathways

    PubMed Central

    Righetti, Karima; Vu, Joseph Ly; Pelletier, Sandra; Vu, Benoit Ly; Glaab, Enrico; Lalanne, David; Pasha, Asher; Patel, Rohan V.; Provart, Nicholas J.; Verdier, Jerome; Leprince, Olivier

    2015-01-01

    Seed longevity, the maintenance of viability during storage, is a crucial factor for preservation of genetic resources and ensuring proper seedling establishment and high crop yield. We used a systems biology approach to identify key genes regulating the acquisition of longevity during seed maturation of Medicago truncatula. Using 104 transcriptomes from seed developmental time courses obtained in five growth environments, we generated a robust, stable coexpression network (MatNet), thereby capturing the conserved backbone of maturation. Using a trait-based gene significance measure, a coexpression module related to the acquisition of longevity was inferred from MatNet. Comparative analysis of the maturation processes in M. truncatula and Arabidopsis thaliana seeds and mining Arabidopsis interaction databases revealed conserved connectivity for 87% of longevity module nodes between both species. Arabidopsis mutant screening for longevity and maturation phenotypes demonstrated high predictive power of the longevity cross-species network. Overrepresentation analysis of the network nodes indicated biological functions related to defense, light, and auxin. Characterization of defense-related wrky3 and nf-x1-like1 (nfxl1) transcription factor mutants demonstrated that these genes regulate some of the network nodes and exhibit impaired acquisition of longevity during maturation. These data suggest that seed longevity evolved by co-opting existing genetic pathways regulating the activation of defense against pathogens. PMID:26410298

  9. Pulsed Lidar Performance/Technical Maturity Assessment

    NASA Technical Reports Server (NTRS)

    Gimmestad, Gary G.; West, Leanne L.; Wood, Jack W.; Frehlich, Rod

    2004-01-01

    This report describes the results of investigations performed by the Georgia Tech Research Institute (GTRI) and the National Center for Atmospheric Research (NCAR) under a task entitled 'Pulsed Lidar Performance/Technical Maturity Assessment' funded by the Crew Systems Branch of the Airborne Systems Competency at the NASA Langley Research Center. The investigations included two tasks, 1.1(a) and 1.1(b). The Tasks discussed in this report are in support of the NASA Virtual Airspace Modeling and Simulation (VAMS) program and are designed to evaluate a pulsed lidar that will be required for active wake vortex avoidance solutions. The Coherent Technologies, Inc. (CTI) WindTracer LIDAR is an eye-safe, 2-micron, coherent, pulsed Doppler lidar with wake tracking capability. The actual performance of the WindTracer system was to be quantified. In addition, the sensor performance has been assessed and modeled, and the models have been included in simulation efforts. The WindTracer LIDAR was purchased by the Federal Aviation Administration (FAA) for use in near-term field data collection efforts as part of a joint NASA/FAA wake vortex research program. In the joint research program, a minimum common wake and weather data collection platform will be defined. NASA Langley will use the field data to support wake model development and operational concept investigation in support of the VAMS project, where the ultimate goal is to improve airport capacity and safety. Task 1.1(a), performed by NCAR in Boulder, Colorado to analyze the lidar system to determine its performance and capabilities based on results from simulated lidar data with analytic wake vortex models provided by NASA, which were then compared to the vendor's claims for the operational specifications of the lidar. Task 1.1(a) is described in Section 3, including the vortex model, lidar parameters and simulations, and results for both detection and tracking of wake vortices generated by Boeing 737s and 747s. Task 1

  10. Quality Management Systems Implementation Compared With Organizational Maturity in Hospital

    PubMed Central

    Moradi, Tayebeh; Jafari, Mehdi; Maleki, Mohammad Reza; Naghdi, Seyran; Ghiyasvand, Hesam

    2016-01-01

    Background: A quality management system can provide a framework for continuous improvement in order to increase the probability of customers and other stakeholders’ satisfaction. The test maturity model helps organizations to assess the degree of maturity in implementing effective and sustained quality management systems; plan based on the current realities of the organization and prioritize their improvement programs. Objectives: We aim to investigate and compare the level of organizational maturity in hospitals with the status of quality management systems implementation. Materials and Methods: This analytical cross sectional study was conducted among hospital administrators and quality experts working in hospitals with over 200 beds located in Tehran. In the first step, 32 hospitals were selected and then 96 employees working in the selected hospitals were studied. The data were gathered using the implementation checklist of quality management systems and the organization maturity questionnaire derived from ISO 10014. The content validity was calculated using Lawshe method and the reliability was estimated using test - retest method and calculation of Cronbach's alpha coefficient. The descriptive and inferential statistics were used to analyze the data using SPSS 18 software. Results: According to the table, the mean score of organizational maturity among hospitals in the first stage of quality management systems implementation was equal to those in the third stage and hypothesis was rejected (p-value = 0.093). In general, there is no significant difference in the organizational maturity between the first and third level hospitals (in terms of implementation of quality management systems). Conclusions: Overall, the findings of the study show that there is no significant difference in the organizational maturity between the hospitals in different levels of the quality management systems implementation and in fact, the maturity of the organizations cannot be

  11. Thermal and hydrocarbon maturation models for coastal California

    SciTech Connect

    Heasler, H.P.; Surdam, R.C.

    1985-02-01

    Hydrocarbon maturation models for coastal California must consider thermal and geochemical constraints imposed by plate tectonics, diagenetic reactions, and the sedimentation history of the region. Plate tectonism drastically effects the thermal history of California basins in many ways. Initially, temperatures in the crust of coastal California are suppressed during subduction of the Farallon plate. With the passage of the Mendocino triple junction, subduction ceases and a void is created into which asthenosphere moves. This elevates temperatures in the basins in a complex manner depending on the time of passage of the Mendocino triple junction and the location of a specific basin. Finite-difference numerical models were developed to approximate the thermal effects of subduction and lithospheric upwelling. Diagenetic reactions and sedimentation history affect both the maturation model and thermal history of a basin. Diagenetic reactions through time in the Miocene Monterey Formation may change thermal conductivity values by 70%. Facies changes also have an important effect on sediment thermal conductivity and hence sediment temperatures. Maturation models indicate varying levels of maturity depending on the method used. Models using the Time Temperature Index of Lopatin indicate the lowest level of maturity. Tissot and Espitalie's method, which uses multiple activation energies and varying constants for the kerogen types, results in an intermediate level of maturity. The highest level of maturity results in an intermediate level of maturity. The highest level of maturity results from the use of the Tissot and Espitalie method modified by using a single activation energy of 178.69 kJ mole/sup -1/ and a constant of 4.92 x 10/sup 13/ hour/sup -1/ as reported by M.D. Lewan for shale from the Phosphoria Formation.

  12. Dual function of the selenoprotein PHGPx during sperm maturation.

    PubMed

    Ursini, F; Heim, S; Kiess, M; Maiorino, M; Roveri, A; Wissing, J; Flohé, L

    1999-08-27

    The selenoprotein phospholipid hydroperoxide glutathione peroxidase (PHGPx) changes its physical characteristics and biological functions during sperm maturation. PHGPx exists as a soluble peroxidase in spermatids but persists in mature spermatozoa as an enzymatically inactive, oxidatively cross-linked, insoluble protein. In the midpiece of mature spermatozoa, PHGPx protein represents at least 50 percent of the capsule material that embeds the helix of mitochondria. The role of PHGPx as a structural protein may explain the mechanical instability of the mitochondrial midpiece that is observed in selenium deficiency.

  13. Development and maturation of primary feathers of redhead ducklings

    USGS Publications Warehouse

    Smart, M.G.

    1965-01-01

    A comparison of the maturation rates of the primaries of redheads (Aythya americana) hatched very early with those hatched very late was made in the 1961 season. Primaries of the early-hatched birds emerged when the birds were 36-38 days old, those of the late-hatched birds when they were 7-10 days younger. This difference was also found in the age at first flight and the age at eventual maturation of all primaries. Primaries of late-hatched birds were significantly shorter in length when mature than were the primaries of early-hatched birds.

  14. Endotoxin-induced nitric oxide production rescues airway growth and maturation in atrophic fetal rat lung explants

    SciTech Connect

    Rae, C.; Cherry, J.I.; Land, F.M.; Land, S.C. . E-mail: s.c.land@dundee.ac.uk

    2006-10-13

    Inflammation induces premature maturation of the fetal lung but the signals causing this effect remain unclear. We determined if nitric oxide (NO) synthesis, evoked by Escherichia coli lipopolysaccharide (LPS, 2 {mu}g ml{sup -1}), participated in this process. Fetal rat lung airway surface complexity rose 2.5-fold over 96 h in response to LPS and was associated with increased iNOS protein expression and activity. iNOS inhibition by N6-(1-iminoethyl)-L-lysine-2HCl (L-NIL) abolished this and induced airway atrophy similar to untreated explants. Surfactant protein-C (SP-C) expression was also induced by LPS and abolished by L-NIL. As TGF{beta} suppresses iNOS activity, we determined if feedback regulation modulated NO-dependent maturation. LPS induced TGF{beta}1 release and SMAD4 nuclear translocation 96 h after treatment. Treatment of explants with a blocking antibody against TGF{beta}1 sustained NO production and airway morphogenesis whereas recombinant TGF{beta}1 antagonized these effects. Feedback regulation of NO synthesis by TGF{beta} may, thus, modulate airway branching and maturation of the fetal lung.

  15. A Regulatory Network-Based Approach Dissects Late Maturation Processes Related to the Acquisition of Desiccation Tolerance and Longevity of Medicago truncatula Seeds1[C][W][OPEN

    PubMed Central

    Verdier, Jerome; Lalanne, David; Pelletier, Sandra; Torres-Jerez, Ivone; Righetti, Karima; Bandyopadhyay, Kaustav; Leprince, Olivier; Chatelain, Emilie; Vu, Benoit Ly; Gouzy, Jerome; Gamas, Pascal; Udvardi, Michael K.; Buitink, Julia

    2013-01-01

    In seeds, desiccation tolerance (DT) and the ability to survive the dry state for prolonged periods of time (longevity) are two essential traits for seed quality that are consecutively acquired during maturation. Using transcriptomic and metabolomic profiling together with a conditional-dependent network of global transcription interactions, we dissected the maturation events from the end of seed filling to final maturation drying during the last 3 weeks of seed development in Medicago truncatula. The network revealed distinct coexpression modules related to the acquisition of DT, longevity, and pod abscission. The acquisition of DT and dormancy module was associated with abiotic stress response genes, including late embryogenesis abundant (LEA) genes. The longevity module was enriched in genes involved in RNA processing and translation. Concomitantly, LEA polypeptides accumulated, displaying an 18-d delayed accumulation compared with transcripts. During maturation, gulose and stachyose levels increased and correlated with longevity. A seed-specific network identified known and putative transcriptional regulators of DT, including ABSCISIC ACID-INSENSITIVE3 (MtABI3), MtABI4, MtABI5, and APETALA2/ ETHYLENE RESPONSE ELEMENT BINDING PROTEIN (AtAP2/EREBP) transcription factor as major hubs. These transcriptional activators were highly connected to LEA genes. Longevity genes were highly connected to two MtAP2/EREBP and two basic leucine zipper transcription factors. A heat shock factor was found at the transition of DT and longevity modules, connecting to both gene sets. Gain- and loss-of-function approaches of MtABI3 confirmed 80% of its predicted targets, thereby experimentally validating the network. This study captures the coordinated regulation of seed maturation and identifies distinct regulatory networks underlying the preparation for the dry and quiescent states. PMID:23929721

  16. A regulatory network-based approach dissects late maturation processes related to the acquisition of desiccation tolerance and longevity of Medicago truncatula seeds.

    PubMed

    Verdier, Jerome; Lalanne, David; Pelletier, Sandra; Torres-Jerez, Ivone; Righetti, Karima; Bandyopadhyay, Kaustav; Leprince, Olivier; Chatelain, Emilie; Vu, Benoit Ly; Gouzy, Jerome; Gamas, Pascal; Udvardi, Michael K; Buitink, Julia

    2013-10-01

    In seeds, desiccation tolerance (DT) and the ability to survive the dry state for prolonged periods of time (longevity) are two essential traits for seed quality that are consecutively acquired during maturation. Using transcriptomic and metabolomic profiling together with a conditional-dependent network of global transcription interactions, we dissected the maturation events from the end of seed filling to final maturation drying during the last 3 weeks of seed development in Medicago truncatula. The network revealed distinct coexpression modules related to the acquisition of DT, longevity, and pod abscission. The acquisition of DT and dormancy module was associated with abiotic stress response genes, including late embryogenesis abundant (LEA) genes. The longevity module was enriched in genes involved in RNA processing and translation. Concomitantly, LEA polypeptides accumulated, displaying an 18-d delayed accumulation compared with transcripts. During maturation, gulose and stachyose levels increased and correlated with longevity. A seed-specific network identified known and putative transcriptional regulators of DT, including ABSCISIC ACID-INSENSITIVE3 (MtABI3), MtABI4, MtABI5, and APETALA2/ ETHYLENE RESPONSE ELEMENT BINDING PROTEIN (AtAP2/EREBP) transcription factor as major hubs. These transcriptional activators were highly connected to LEA genes. Longevity genes were highly connected to two MtAP2/EREBP and two basic leucine zipper transcription factors. A heat shock factor was found at the transition of DT and longevity modules, connecting to both gene sets. Gain- and loss-of-function approaches of MtABI3 confirmed 80% of its predicted targets, thereby experimentally validating the network. This study captures the coordinated regulation of seed maturation and identifies distinct regulatory networks underlying the preparation for the dry and quiescent states.

  17. Study of the Role of Cytosolic Phospholipase A2 Alpha in Eicosanoid Generation and Thymocyte Maturation in the Thymus

    PubMed Central

    Rousseau, Matthieu; Naika, Gajendra S.; Perron, Jean; Jacques, Frederic; Gelb, Michael H.; Boilard, Eric

    2015-01-01

    The thymus is a primary lymphoid organ, home of maturation and selection of thymocytes for generation of functional T-cells. Multiple factors are involved throughout the different stages of the maturation process to tightly regulate T-cell production. The metabolism of arachidonic acid by cyclooxygenases, lipoxygenases and specific isomerases generates eicosanoids, lipid mediators capable of triggering cellular responses. In this study, we determined the profile of expression of the eicosanoids present in the mouse thymus at different stages of thymocyte development. As the group IVA cytosolic phospholipase A2 (cPLA2α) catalyzes the hydrolysis of phospholipids, thereby generating arachidonic acid, we further verified its contribution by including cPLA2α deficient mice to our investigations. We found that a vast array of eicosanoids is expressed in the thymus, which expression is substantially modulated through thymocyte development. The cPLA2α was dispensable in the generation of most eicosanoids in the thymus and consistently, the ablation of the cPLA2α gene in mouse thymus and the culture of thymuses from human newborns in presence of the cPLA2α inhibitor pyrrophenone did not impact thymocyte maturation. This study provides information on the eicosanoid repertoire present during thymocyte development and suggests that thymocyte maturation can occur independently of cPLA2α. PMID:25969996

  18. Study of the role of cytosolic phospholipase A2 alpha in eicosanoid generation and thymocyte maturation in the thymus.

    PubMed

    Rousseau, Matthieu; Naika, Gajendra S; Perron, Jean; Jacques, Frederic; Gelb, Michael H; Boilard, Eric

    2015-01-01

    The thymus is a primary lymphoid organ, home of maturation and selection of thymocytes for generation of functional T-cells. Multiple factors are involved throughout the different stages of the maturation process to tightly regulate T-cell production. The metabolism of arachidonic acid by cyclooxygenases, lipoxygenases and specific isomerases generates eicosanoids, lipid mediators capable of triggering cellular responses. In this study, we determined the profile of expression of the eicosanoids present in the mouse thymus at different stages of thymocyte development. As the group IVA cytosolic phospholipase A2 (cPLA2α) catalyzes the hydrolysis of phospholipids, thereby generating arachidonic acid, we further verified its contribution by including cPLA2α deficient mice to our investigations. We found that a vast array of eicosanoids is expressed in the thymus, which expression is substantially modulated through thymocyte development. The cPLA2α was dispensable in the generation of most eicosanoids in the thymus and consistently, the ablation of the cPLA2α gene in mouse thymus and the culture of thymuses from human newborns in presence of the cPLA2α inhibitor pyrrophenone did not impact thymocyte maturation. This study provides information on the eicosanoid repertoire present during thymocyte development and suggests that thymocyte maturation can occur independently of cPLA2α.

  19. Sinomenine promotes differentiation but impedes maturation and co-stimulatory molecule expression of human monocyte-derived dendritic cells.

    PubMed

    Chen, Yongwen; Yang, Chengying; Jin, Naishi; Xie, Zhunyi; Fei, Lie; Jia, Zhengcai; Wu, Yuzhang

    2007-08-01

    Dendritic cells (DC) excel at presenting antigen to T cells and thus make a key contribution to the induction of primary and secondary immune responses. Sinomenine has been used for centuries in the treatment of patients with autoimmune diseases as it possesses immunosuppressive and anti-inflammatory activities. However, the effect of sinomenine on the differentiation, maturation, and functionality of DC derived from monocytes has not been studied. We show here that DC differentiation is promoted when monocytes are treated with GM-CSF and IL-4 (IL-4) in the presence of sinomenine (200 microg/ml), as evidenced by the upregulation of CD1a while CD14 was decreased. In addition, incubation of immature DC with sinomenine significantly blunted lipopolysaccharide (LPS)-induced DC maturation, as shown by the reduction of expression of the maturation marker CD83 and co-stimulatory molecules, including CD86, B7-H1, and CD40. Moreover, sinomenine also prevented decreases in antigen (FITC-Dextran or Lucifer Yellow) uptake by LPS-treated DC. Mixed lymphocyte reactions (MLRs) revealed that sinomenine-treated DC impede the secretion of the cytokines IL-2 and IFN-gamma by co-cultured CD4(+) T cells. Therefore, modulation of DC differentiation, maturation, and functionality by sinomenine is of potential relevance to its immunomodulatory effects in controlling specific immune responses in autoimmune diseases, transplantation, and other immune-mediated conditions.

  20. Specific involvement of gonadal hormones in the functional maturation of growth hormone releasing hormone (GHRH) neurons.

    PubMed

    Gouty-Colomer, Laurie-Anne; Méry, Pierre-François; Storme, Emilie; Gavois, Elodie; Robinson, Iain C; Guérineau, Nathalie C; Mollard, Patrice; Desarménien, Michel G

    2010-12-01

    Growth hormone (GH) is the key hormone involved in the regulation of growth and metabolism, two functions that are highly modulated during infancy. GH secretion, controlled mainly by GH releasing hormone (GHRH), has a characteristic pattern during postnatal development that results in peaks of blood concentration at birth and puberty. A detailed knowledge of the electrophysiology of the GHRH neurons is necessary to understand the mechanisms regulating postnatal GH secretion. Here, we describe the unique postnatal development of the electrophysiological properties of GHRH neurons and their regulation by gonadal hormones. Using GHRH-eGFP mice, we demonstrate that already at birth, GHRH neurons receive numerous synaptic inputs and fire large and fast action potentials (APs), consistent with effective GH secretion. Concomitant with the GH secretion peak occurring at puberty, these neurons display modifications of synaptic input properties, decrease in AP duration, and increase in a transient voltage-dependant potassium current. Furthermore, the modulation of both the AP duration and voltage-dependent potassium current are specifically controlled by gonadal hormones because gonadectomy prevented the maturation of these active properties and hormonal treatment restored it. Thus, GHRH neurons undergo specific developmental modulations of their electrical properties over the first six postnatal weeks, in accordance with hormonal demand. Our results highlight the importance of the interaction between the somatotrope and gonadotrope axes during the establishment of adapted neuroendocrine functions.

  1. Skeletal maturation analysis by morphological evaluation of the cervical vertebrae.

    PubMed

    Santos, Eduardo César Almada; Bertoz, Francisco Antônio; Arantes, Flávia de Moraes; Reis, Patrícia Maria Pizzo; de Bertoz, André Pinheiro Magalhães

    2006-01-01

    The determination of skeletal maturation by morphological evaluation of the cervical vertebrae was evaluated in a 100 cephalograms. The analysis showed that this method was reproducible for assessing the individual's growth curve.

  2. Maturation of normal primate white matter: computed tomographic correlation

    SciTech Connect

    Quencer, R.M.

    1982-09-01

    Five infant baboons were examined with computed tomography (CT) during the first year of their lives to determine the rate and degree of normal white matter maturation in frontal, occipital, and parietal areas. The increase in CT numbers with age was correlated with gross and histologic specimens. Two phases of maturation were identified: a rapid phase (first 8-12 weeks) and a gradual phase (after 12 weeks). Frontal white matter was the most immature in the immediate postnatal period but it became equal in attenuation to the other regions by 4 weeks of age. Knowledge of white matter maturation rates may be particularly useful in cases of neonatal hypoxia/ischemia where zones of periventricular hypodensity are identified. The failure of such regions to follow a normal rate of maturation may indicate damage to the white matter and have significant prognostic implications.

  3. Mitofusin-2 is required for mouse oocyte meiotic maturation

    PubMed Central

    Zhang, Jing-Hua; Zhang, Teng; Gao, Si-Hua; Wang, Ke; Yang, Xiu-Yan; Mo, Fang-Fang; Na Yu; An, Tian; Li, Yu-Feng; Hu, Ji-Wei; Jiang, Guang-Jian

    2016-01-01

    Mitofusin-2 (Mfn2) is essential for embryonic development, anti-apoptotic events, protection against free radical-induced lesions, and mitochondrial fusion in many cells. However, little is known about its mechanism and function during oocyte maturation. In this study, we found that Mfn2 was expressed in the cytoplasm during different stages of mouse oocyte maturation. Mfn2 was mainly associated with α-tubulin during oocyte maturation. Knockdown of Mfn2 by specific siRNA injection into oocytes caused the mitochondrial morphology and quantity to change, resulting in severely defective spindles and misaligned chromosomes. This led to metaphase I arrest and the failure of first polar body extrusion. Furthermore, Mfn2 depletion from GV stage oocytes caused the redistribution of p38 MAPK in oocyte cytoplasm. These findings provide insights into potential mechanisms of Mfn2-mediated cellular alterations, which may have significant implications for oocyte maturation. PMID:27485634

  4. Time Perspective in Vocational Maturity and Career Decision Making.

    ERIC Educational Resources Information Center

    Savickas, Mark L.; And Others

    1984-01-01

    Investigated the hypothesis that time perspective is a component in vocational maturity and career decision making with college freshmen (N=97). Results supported the hypothesis and specifically linked time perspective to planfulness and degree of indecision. (LLL)

  5. VIEW ALONG SEVENTEENTH STREET. NOTE THE MATURE SILK OAK TREES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW ALONG SEVENTEENTH STREET. NOTE THE MATURE SILK OAK TREES LINING THE STREET, WHICH DO NOT PROVIDE A CANOPY VIEW FACING NORTHWEST. - Hickam Field, Hickam Historic Housing, Honolulu, Honolulu County, HI

  6. Cortex Matures Faster in Youths With Highest IQ

    MedlinePlus

    ... NIH Cortex Matures Faster in Youths With Highest IQ Past Issues / Summer 2006 Table of Contents For ... on. Photo: Getty image (StockDisc) Youths with superior IQ are distinguished by how fast the thinking part ...

  7. IMMUNE SYSTEM MATURITY AND SENSITIVITY TO CHEMICAL EXPOSURE

    EPA Science Inventory

    It is well established that human diseases associated with abnormal immune function, including some common infectious diseases and asthma, are considerably more prevalent at younger ages. The immune system continues to mature after birth, and functional immaturity accounts for m...

  8. Antibody Affinity Maturation in Fishes—Our Current Understanding

    PubMed Central

    Magor, Brad G.

    2015-01-01

    It has long been believed that fish lack antibody affinity maturation, in part because they were thought to lack germinal centers. Recent research done on sharks and bony fishes indicates that these early vertebrates are able to affinity mature their antibodies. This article reviews the functionality of the fish homologue of the immunoglobulin (Ig) mutator enzyme activation-induced cytidine deaminase (AID). We also consider the protein and molecular evidence for Ig somatic hypermutation and antibody affinity maturation. In the context of recent evidence for a putative proto-germinal center in fishes we propose some possible reasons that observed affinity maturation in fishes often seems lacking and propose future work that might shed further light on this process in fishes. PMID:26264036

  9. Pattern of vitellogenesis and follicle maturational competence during the ovarian follicular cycle of Fundulus heteroclitus.

    PubMed

    Cerdá, J; Calman, B G; LaFleur, G J; Limesand, S

    1996-07-01

    The patterns of vitellogenesis and follicle maturational competence were examined across the semilunar spawning cycle of Fundulus heteroclitus. Daily egg collection showed spawning cyclicity in six experimental groups, with a mean period between spawnings of 14.9 +/- 0.3 days, indicated by the nonlinear regression sine-curve matching analysis. Each cycle was then dated from Day -7 to Day 7, with Day 0 as the peak egg-collection day. Females from each group were sampled on selected days during two to three consecutive spawning cycles, and these days were each chronologically given a temporal relation to Day 0 to pool the data into a composite. The analysis of the size-frequency distribution of ovarian follicles > or = 0.5-mm diameter across the composite revealed a constant recruitment of small follicles (0.5- to 0.7-mm diameter) into vitellogenesis, which was supported by the continuous presence of vitellogenin (Vtg) I mRNA in the liver of the females. The plasma levels of Vtg were also essentially constant across the cycle, except for a progressive decrease from Day -7 through Day 3 that could be related to a more active Vtg uptake by a dominant population of follicles up to 1.7 mm in diameter. A second and more selective recruitment of full-grown follicles (1.3- to 1.4-mm diameter) toward maturation was noted at Days -5, -4, which appeared associated with high plasma levels of estradiol-17 beta. However, the responsiveness of those follicles undergoing oocyte maturation in vitro after gonadotropin and maturation-inducing steroid (MIS), 17, 20 beta-dihydroxy-4-pregnen-3-one, stimulation dramatically declined from Days -1, 0, 1 to Days 4, 5, concomitantly with an increase of the population of the largest follicles (1.8- to 2.1-mm diameter) in the ovary. These findings extend previous observations on the process of follicular recruitment in F. heteroclitus and indicate that full-grown follicles may be recruited into maturation by a mechanism that modulates the

  10. In vitro maturation and artificial activation of donkey oocytes.

    PubMed

    Zhao, Gaoping; Wu, Kaifeng; Cui, Liang; Zhao, Lixia; Liu, Yiyi; Tan, Xiuwen; Zhou, Huanmin

    2011-09-01

    Three media were evaluated for their ability to support in vitro maturation of donkey (Equus asinus) oocytes and their development after parthenogenetic activation. The basal medium for Medium 1 (M1) and Medium 2 (M2) was M199 and DMEM/F12 respectively, whereas, Medium 3 (M3) consisted of equal parts (v/v) of M199 and DMEM/F12. All three media were supplemented with 10% (v/v) fetal calf serum, 0.01 units/mL porcine FSH, 0.01 units/mL equine LH, 200 ng/mL insulin-like growth factor 1(IGF-I), 10 μl/mL insulin-transferrin-selenium (ITS), 0.1 mg/mL taurine, 0.1 mg/mL L-cysteine, 0.05 mg/mL L-glutamine, 0.11 mg/mL sodium pyruvate, and 25 mg/mL gentamycin. There were no significant differences among the three maturation media for oocyte maturation. Maturation rate of donkey oocytes in M1 was 53% for compact (Cp) cumulus-oocyte complexes and 75% for expanded (Ex) cumulus-oocyte complexes; in M2 these were 55 and 77%, respectively; and in M3, 58 and 75%. The percentage of cleaved parthenotes and 4- or 8-cell embryos were not significantly different for oocytes matured in the various media (61 and 24% for M1; 66 and 32% for M2; and 67 and 33% for M3). Oocytes matured in M3 tended to yield a higher rate of advanced embryo development (morula) than oocytes matured in M1 (22 vs 9%; P = 0.07). In conclusion, donkey oocytes were matured and parthenogenetically activated in vitro, using methods similar to those used in the horse.

  11. Study Progress on Tissue Culture of Maize Mature Embryo

    NASA Astrophysics Data System (ADS)

    Wang, Hongzhen; Cheng, Jun; Cheng, Yanping; Zhou, Xioafu

    It has been paid more and more attention on maize tissue culture as it is a basic work in maize genetic transformation, especially huge breakthrough has been made in maize tissue culture utilizing mature embryos as explants in the recent years. This paper reviewed the study progress on maize tissue culture and plant regeneration utilizing mature embryos as explants from callus induction, subculture, plant regeneration and browning reduction and so on.

  12. Progesterone influences cytoplasmic maturation in porcine oocytes developing in vitro

    PubMed Central

    Jin, Yong-Xun; Kwon, Jeong-Woo

    2016-01-01

    Progesterone (P4), an ovarian steroid hormone, is an important regulator of female reproduction. In this study, we explored the influence of progesterone on porcine oocyte nuclear maturation and cytoplasmic maturation and development in vitro. We found that the presence of P4 during oocyte maturation did not inhibit polar body extrusions but significantly increased glutathione and decreased reactive oxygen species (ROS) levels relative to that in control groups. The incidence of parthenogenetically activated oocytes that could develop to the blastocyst stage was higher (p < 0.05) when oocytes were exposed to P4 as compared to that in the controls. Cell numbers were increased in the P4-treated groups. Further, the P4-specific inhibitor mifepristone (RU486) prevented porcine oocyte maturation, as represented by the reduced incidence (p < 0.05) of oocyte first polar body extrusions. RU486 affected maturation promoting factor (MPF) activity and maternal mRNA polyadenylation status. In general, these data show that P4 influences the cytoplasmic maturation of porcine oocytes, at least partially, by decreasing their polyadenylation, thereby altering maternal gene expression. PMID:27672508

  13. Nuclear status of immature and mature stallion spermatozoa.

    PubMed

    Dias, G M; Retamal, C A; Tobella, L; Arnholdt, A C V; López, M L

    2006-07-15

    'The highly packed chromatin of mature spermatozoa results from replacement of somatic-like histones by highly basic arginine- and cysteine-rich protamines during spermatogenesis, with additional conformational changes in chromatin structure during epididymal transit. The objective of the present study was to compare the nuclear characteristics of immature and mature epididymal stallion spermatozoa, using a variety of experimental approaches. Resistance to in vitro decondensation of chromatin, following exposure to SDS-DTT and alkaline thioglycolate, increased significantly in mature spermatozoa. Evaluation of the thiol-disulfide status (monobromobimane labeling) demonstrated that immature cells obtained from ductulli efferentes contained mostly thiol groups, whereas these groups were oxidized in mature cells collected from the cauda epididymidis. Based on atomic absorption spectrophotometry, maturation of stallion spermatozoa was accompanied by a 60% reduction in the Zn(2+) content of sperm cells, concomitant with increased concentrations of this ion in epididymal fluid. Furthermore, the degree of disulfide bonding was inversely correlated with susceptibility of chromatin to acid denaturation (SCSA). Collectively, these data were consistent with the hypothesis that maturation of stallion spermatozoa involves oxidation of sulphydryl groups to form intra- and intermolecular disulfide links between adjacent protamines, with loss of zinc as an integral feature. These changes endow mechanical and chemical resistance to the nucleus, ensuring efficient transmission of the paternal genome at fertilization.

  14. Predictive Capability Maturity Model for computational modeling and simulation.

    SciTech Connect

    Oberkampf, William Louis; Trucano, Timothy Guy; Pilch, Martin M.

    2007-10-01

    The Predictive Capability Maturity Model (PCMM) is a new model that can be used to assess the level of maturity of computational modeling and simulation (M&S) efforts. The development of the model is based on both the authors experience and their analysis of similar investigations in the past. The perspective taken in this report is one of judging the usefulness of a predictive capability that relies on the numerical solution to partial differential equations to better inform and improve decision making. The review of past investigations, such as the Software Engineering Institute's Capability Maturity Model Integration and the National Aeronautics and Space Administration and Department of Defense Technology Readiness Levels, indicates that a more restricted, more interpretable method is needed to assess the maturity of an M&S effort. The PCMM addresses six contributing elements to M&S: (1) representation and geometric fidelity, (2) physics and material model fidelity, (3) code verification, (4) solution verification, (5) model validation, and (6) uncertainty quantification and sensitivity analysis. For each of these elements, attributes are identified that characterize four increasing levels of maturity. Importantly, the PCMM is a structured method for assessing the maturity of an M&S effort that is directed toward an engineering application of interest. The PCMM does not assess whether the M&S effort, the accuracy of the predictions, or the performance of the engineering system satisfies or does not satisfy specified application requirements.

  15. Localized epigenetic silencing of a damage-activated WNT enhancer limits regeneration in mature Drosophila imaginal discs.

    PubMed

    Harris, Robin E; Setiawan, Linda; Saul, Josh; Hariharan, Iswar K

    2016-02-03

    Many organisms lose the capacity to regenerate damaged tissues as they mature. Damaged Drosophila imaginal discs regenerate efficiently early in the third larval instar (L3) but progressively lose this ability. This correlates with reduced damage-responsive expression of multiple genes, including the WNT genes wingless (wg) and Wnt6. We demonstrate that damage-responsive expression of both genes requires a bipartite enhancer whose activity declines during L3. Within this enhancer, a damage-responsive module stays active throughout L3, while an adjacent silencing element nucleates increasing levels of epigenetic silencing restricted to this enhancer. Cas9-mediated deletion of the silencing element alleviates WNT repression, but is, in itself, insufficient to promote regeneration. However, directing Myc expression to the blastema overcomes repression of multiple genes, including wg, and restores cellular responses necessary for regeneration. Localized epigenetic silencing of damage-responsive enhancers can therefore restrict regenerative capacity in maturing organisms without compromising gene functions regulated by developmental signals.

  16. Local BLyS production by T follicular cells mediates retention of high affinity B cells during affinity maturation

    PubMed Central

    Goenka, Radhika; Matthews, Andrew H.; Zhang, Bochao; O’Neill, Patrick J.; Scholz, Jean L.; Migone, Thi-Sau; Leonard, Warren J.; Stohl, William; Hershberg, Uri

    2014-01-01

    We have assessed the role of B lymphocyte stimulator (BLyS) and its receptors in the germinal center (GC) reaction and affinity maturation. Despite ample BLyS retention on B cells in follicular (FO) regions, the GC microenvironment lacks substantial BLyS. This reflects IL-21–mediated down-regulation of the BLyS receptor TACI (transmembrane activator and calcium modulator and cyclophilin ligand interactor) on GC B cells, thus limiting their capacity for BLyS binding and retention. Within the GC, FO helper T cells (TFH cells) provide a local source of BLyS. Whereas T cell–derived BLyS is dispensable for normal GC cellularity and somatic hypermutation, it is required for the efficient selection of high affinity GC B cell clones. These findings suggest that during affinity maturation, high affinity clones rely on TFH-derived BLyS for their persistence. PMID:24367004

  17. Maturation of the human fetal startle response: Evidence for sex-specific maturation of the human fetus1

    PubMed Central

    Buss, Claudia; Davis, Elysia Poggi; Class, Quetzal A.; Gierczak, Matt; Pattillo, Carol; Glynn, Laura M.; Sandman, Curt A.

    2009-01-01

    Despite the evidence for early fetal experience exerting programming influences on later neurological development and health risk, very few prospective studies of human fetal behavior have been reported. In a prospective longitudinal study, fetal nervous system maturation was serially assessed by monitoring fetal heart rate (FHR) responses to vibroacoustic stimulation (VAS) in 191 maternal/fetal dyads. Responses were not detected at 26 weeks gestational age (GA). Sex-specific, age-characteristic changes in the FHR response to VAS were observed by 31 weeks’ GA. Males showed larger responses and continued to exhibit maturational changes until 37 weeks’ GA, females however, presented with a mature FHR startle response by 31 weeks’ GA. The results indicate that there are different rates of maturation in the male and female fetus that may have implications for sex-specific programming influences. PMID:19726143

  18. Wideband Linear Phase Modulator

    NASA Technical Reports Server (NTRS)

    Mysoor, Narayan R.; Mueller, Robert O.

    1994-01-01

    Phase modulator for transmission in X band provides large phase deviation that remains nearly linear with voltage over relatively wide range. Operates with low loss over wide frequency band and with stable characteristics over wide temperature range. Phase modulator contains two varactor-diode phase shifters coupled via circulators. Separate drive circuit applies modulating voltages to varactor diodes. Modulation voltages vary in accordance with input to drive circuit.

  19. Roles of the signal peptide and mature domains in the secretion and maturation of the neutral metalloprotease from Streptomyces cacaoi.

    PubMed Central

    Chang, S C; Su, M H; Lee, Y H

    1997-01-01

    The neutral metalloprotease (Npr) of Streptomyces cacaoi is synthesized as a prepro-Npr precursor form consisting of a secretory signal peptide, a propeptide and the mature metalloprotease. The maturation of Npr occurs extracellularly via an autoproteolytic processing of the secreted pro-Npr. The integrity of the propeptide is essential for the formation of mature active Npr but not for its secretion [Chang, Chang and Lee (1994) J. Biol. Chem. 269, 3548-3554]. In this study we investigated whether the secretion and maturation of Npr require the integrity of its signal peptide region and mature protease domain. Five signal peptide mutants were generated, including the substitution mutations at the positively charged region (mutant IR6LE), the central hydrophobic region (mutants GI19EL and G19N), the boundary of the hydrophobic core-cleavage region (mutant P30L) and at the residues adjacent to the signal peptidase cleavage site (mutant YA33SM). All these lesions delayed the export of Npr to the growth medium and also resulted in a 2-10-fold decrease in Npr export. The most severe effect was noted in mutants GI19EL and P30L. When these signal peptide mutations were fused separately with the propeptide lacking the Npr mature domain, the secretory defect on the propeptide was also observed, and this impairment was again more severely expressed in mutants GI19EL and P30L. Thus the Npr signal peptide seems to have more constraints on the hydrophobic core region and at the proline residue within the boundary of the hydrophobic core-cleavage site. Deletion mutations within the C-terminal mature protease domain that left its active site intact still blocked the proteolytic processing of mutant precursor forms of pro-Npr, although their secretions were unaffected. These results, together with our previous findings, strongly suggest that the signal peptide of Npr plays a pivotal role in the secretion of both Npr and the propeptide, but not in the maturation of Npr. On the

  20. Modulation formats for 100G and beyond

    NASA Astrophysics Data System (ADS)

    Lach, Eugen; Idler, Wilfried

    2011-10-01

    This paper reviews technological options for the modulation formats for serial optical transmission of 100 Gb/s and beyond. In the first part an overview on various modulation formats for 100 Gbit/s is presented, covering classical binary electronic time division multiplexed 100 Gbit/s NRZ systems, operating a highest speed, and mature product solutions of system vendors running at lower symbol rates which are using quaternary phase shift keying and polarization division multiplexing, coherent technologies and digital signal processing in the receiver. The second part is focusing on the next generation of transmission systems carrying data at channel bitrates higher than 100 Gbit/s, e.g. 400 Gbit/s up to 1 Tbit/s or even beyond, which may apply higher constellation M-QAM modulation of a single carrier or multiple electrical subcarriers and optical superchannels which also form one WDM channel. At both parts, for 100 Gbit/s and higher bitrates, the paper provides a performance comparison together with the main characteristics of the modulation formats and indicates appropriate application areas of transport technologies for future networks.