Golgi enrichment and proteomic analysis of developing Pinus radiata xylem by free-flow electrophoresis.

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Harriet T Parsons

Full Text Available Our understanding of the contribution of Golgi proteins to cell wall and wood formation in any woody plant species is limited. Currently, little Golgi proteomics data exists for wood-forming tissues. In this study, we attempted to address this issue by generating and analyzing Golgi-enriched membrane preparations from developing xylem of compression wood from the conifer Pinus radiata. Developing xylem samples from 3-year-old pine trees were harvested for this purpose at a time of active growth and subjected to a combination of density centrifugation followed by free flow electrophoresis, a surface charge separation technique used in the enrichment of Golgi membranes. This combination of techniques was successful in achieving an approximately 200-fold increase in the activity of the Golgi marker galactan synthase and represents a significant improvement for proteomic analyses of the Golgi from conifers. A total of thirty known Golgi proteins were identified by mass spectrometry including glycosyltransferases from gene families involved in glucomannan and glucuronoxylan biosynthesis. The free flow electrophoresis fractions of enriched Golgi were highly abundant in structural proteins (actin and tubulin indicating a role for the cytoskeleton during compression wood formation. The mass spectrometry proteomics data associated with this study have been deposited to the ProteomeXchange with identifier PXD000557.

Mena–GRASP65 interaction couples actin polymerization to Golgi ribbon linking

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Tang, Danming; Zhang, Xiaoyan; Huang, Shijiao; Yuan, Hebao; Li, Jie; Wang, Yanzhuang

2016-01-01

In mammalian cells, the Golgi reassembly stacking protein 65 (GRASP65) has been implicated in both Golgi stacking and ribbon linking by forming trans-oligomers through the N-terminal GRASP domain. Because the GRASP domain is globular and relatively small, but the gaps between stacks are large and heterogeneous, it remains puzzling how GRASP65 physically links Golgi stacks into a ribbon. To explore the possibility that other proteins may help GRASP65 in ribbon linking, we used biochemical methods and identified the actin elongation factor Mena as a novel GRASP65-binding protein. Mena is recruited onto the Golgi membranes through interaction with GRASP65. Depleting Mena or disrupting actin polymerization resulted in Golgi fragmentation. In cells, Mena and actin were required for Golgi ribbon formation after nocodazole washout; in vitro, Mena and microfilaments enhanced GRASP65 oligomerization and Golgi membrane fusion. Thus Mena interacts with GRASP65 to promote local actin polymerization, which facilitates Golgi ribbon linking. PMID:26538023

The small G protein Arl5 contributes to endosome-to-Golgi traffic by aiding the recruitment of the GARP complex to the Golgi

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Cláudia Rosa-Ferreira

2015-03-01

Full Text Available The small G proteins of the Arf family play critical roles in membrane trafficking and cytoskeleton organization. However, the function of some members of the family remains poorly understood including Arl5 which is widely conserved in eukaryotes. Humans have two closely related Arl5 paralogues (Arl5a and Arl5b, and both Arl5a and Arl5b localize to the trans-Golgi with Arl5b being involved in retrograde traffic from endosomes to the Golgi apparatus. To investigate the function of Arl5, we have used Drosophila melanogaster as a model system. We find that the single Arl5 orthologue in Drosophila also localizes to the trans-Golgi, but flies lacking the Arl5 gene are viable and fertile. By using both liposome and column based affinity chromatography methods we find that Arl5 interacts with the Golgi-associated retrograde protein (GARP complex that acts in the tethering of vesicles moving from endosomes to the trans-Golgi network (TGN. In Drosophila tissues the GARP complex is partially displaced from the Golgi when Arl5 is absent, and the late endosomal compartment is enlarged. In addition, in HeLa cells GARP also becomes cytosolic upon depletion of Arl5b. These phenotypes are consistent with a role in endosome-to-Golgi traffic, but are less severe than loss of GARP itself. Thus it appears that Arl5 is one of the factors that directs the recruitment of the GARP complex to the trans-Golgi, and this function is conserved in both flies and humans.

The asymmetrical structure of Golgi apparatus membranes revealed by in situ atomic force microscope.

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Haijiao Xu

Full Text Available The Golgi apparatus has attracted intense attentions due to its fascinating morphology and vital role as the pivot of cellular secretory pathway since its discovery. However, its complex structure at the molecular level remains elusive due to limited approaches. In this study, the structure of Golgi apparatus, including the Golgi stack, cisternal structure, relevant tubules and vesicles, were directly visualized by high-resolution atomic force microscope. We imaged both sides of Golgi apparatus membranes and revealed that the outer leaflet of Golgi membranes is relatively smooth while the inner membrane leaflet is rough and covered by dense proteins. With the treatment of methyl-β-cyclodextrin and Triton X-100, we confirmed the existence of lipid rafts in Golgi apparatus membrane, which are mostly in the size of 20 nm -200 nm and appear irregular in shape. Our results may be of significance to reveal the structure-function relationship of the Golgi complex and pave the way for visualizing the endomembrane system in mammalian cells at the molecular level.

Golgi structure formation, function, and post-translational modifications in mammalian cells.

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Huang, Shijiao; Wang, Yanzhuang

2017-01-01

The Golgi apparatus is a central membrane organelle for trafficking and post-translational modifications of proteins and lipids in cells. In mammalian cells, it is organized in the form of stacks of tightly aligned flattened cisternae, and dozens of stacks are often linked laterally into a ribbon-like structure located in the perinuclear region of the cell. Proper Golgi functionality requires an intact architecture, yet Golgi structure is dynamically regulated during the cell cycle and under disease conditions. In this review, we summarize our current understanding of the relationship between Golgi structure formation, function, and regulation, with focus on how post-translational modifications including phosphorylation and ubiquitination regulate Golgi structure and on how Golgi unstacking affects its functions, in particular, protein trafficking, glycosylation, and sorting in mammalian cells.

A small-molecule switch for Golgi sulfotransferases.

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de Graffenried, Christopher L; Laughlin, Scott T; Kohler, Jennifer J; Bertozzi, Carolyn R

2004-11-30

The study of glycan function is a major frontier in biology that could benefit from small molecules capable of perturbing carbohydrate structures on cells. The widespread role of sulfotransferases in modulating glycan function makes them prime targets for small-molecule modulators. Here, we report a system for conditional activation of Golgi-resident sulfotransferases using a chemical inducer of dimerization. Our approach capitalizes on two features shared by these enzymes: their requirement of Golgi localization for activity on cellular substrates and the modularity of their catalytic and localization domains. Fusion of these domains to the proteins FRB and FKBP enabled their induced assembly by the natural product rapamycin. We applied this strategy to the GlcNAc-6-sulfotransferases GlcNAc6ST-1 and GlcNAc6ST-2, which collaborate in the sulfation of L-selectin ligands. Both the activity and specificity of the inducible enzymes were indistinguishable from their WT counterparts. We further generated rapamycin-inducible chimeric enzymes comprising the localization domain of a sulfotransferase and the catalytic domain of a glycosyltransferase, demonstrating the generality of the system among other Golgi enzymes. The approach provides a means for studying sulfate-dependent processes in cellular systems and, potentially, in vivo.

A novel Golgi retention signal RPWS for tumor suppressor UBIAD1.

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Xian Wang

Full Text Available UBIAD1 plays critical roles in physiology including vitamin K and CoQ10 biosynthesis as well as pathophysiology including dyslipimedia-induced SCD (Schnyder's corneal dystrophy, Parkinson's disease, cardiovascular disease and bladder carcinoma. Since the subcellular localization of UBIAD1 varies in different cell types, characterization of the exact subcellular localization of UBIAD1 in specific human disease is vital for understanding its molecular mechanism. As UBIAD1 suppresses bladder carcinoma, we studied its subcellular localization in human bladder carcinoma cell line T24. Since fluorescent images of UBIAD1-EGFP in T24, human prostate cancer cell line PC-3, human embryonic kidney cell line HEK293 and human hepatocyte cell line L02 are similar, these four cell lines were used for present study. Using a combination of fluorescent microscopy and immunohistochemistry, it was found that UBIAD1 localized on the Golgi and endoplasmic reticulum (ER, but not on the plasma membrane, of T24 and HEK293 cells. Using scanning electron microscopy and western blot analysis, we found that UBIAD1 is enriched in the Golgi fraction extracted from the L02 cells, verifying the Golgi localization of UBAID1. Site-directed mutagenesis showed that the RPWS motif, which forms an Arginine finger on the UBIAD1 N terminus, serves as the Golgi retention signal. With both cycloheximide and brefeldin A inhibition assays, it was shown that UBIAD1 may be transported from the endoplasmic reticulum (ER to the Golgi by a COPII-mediated mechanism. Based upon flow cytometry analysis, it is shown that mutation of the RPWS motif reduced the UBIAD1-induced apoptosis of T24 cells, indicating that the proper Golgi localization of UBIAD1 influences its tumor suppressant activity. This study paves the way for further understanding the molecular mechanism of UBIAD1 in human diseases.

Mena-GRASP65 interaction couples actin polymerization to Golgi ribbon linking.

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Tang, Danming; Zhang, Xiaoyan; Huang, Shijiao; Yuan, Hebao; Li, Jie; Wang, Yanzhuang

2016-01-01

In mammalian cells, the Golgi reassembly stacking protein 65 (GRASP65) has been implicated in both Golgi stacking and ribbon linking by forming trans-oligomers through the N-terminal GRASP domain. Because the GRASP domain is globular and relatively small, but the gaps between stacks are large and heterogeneous, it remains puzzling how GRASP65 physically links Golgi stacks into a ribbon. To explore the possibility that other proteins may help GRASP65 in ribbon linking, we used biochemical methods and identified the actin elongation factor Mena as a novel GRASP65-binding protein. Mena is recruited onto the Golgi membranes through interaction with GRASP65. Depleting Mena or disrupting actin polymerization resulted in Golgi fragmentation. In cells, Mena and actin were required for Golgi ribbon formation after nocodazole washout; in vitro, Mena and microfilaments enhanced GRASP65 oligomerization and Golgi membrane fusion. Thus Mena interacts with GRASP65 to promote local actin polymerization, which facilitates Golgi ribbon linking. © 2016 Tang et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Morphometric golgi study of some cortical locations in wag/rij and aci rat strains

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Karpova, A.V.; Bikbaev, A.F.; Coenen, A.M.L.; Luijtelaar, E.L.J.M. van; Luijtelaar, E.L.J.M. van; Kuznetsova, G.D.; Coenen, A.M.L.; Chepurnov, S.A.

2004-01-01

The present study was aimed to investigate the neuronal organization of two neocortical frontal zones using a Golgi staining technique in genetic epileptic rats, WAG/Rij's. One cortical zone was a specific part of the somatosensory cortex, which was recently proposed to contain a cortical epileptic

The Cirque du Soleil of Golgi membrane dynamics.

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Bankaitis, Vytas A

2009-07-27

The role of lipid metabolic enzymes in Golgi membrane remodeling is a subject of intense interest. Now, in this issue, Schmidt and Brown (2009. J. Cell Biol. doi:10.1083/jcb.200904147) report that lysophosphatidic acid-specific acyltransferase, LPAAT3, contributes to Golgi membrane dynamics by suppressing tubule formation.

The Cirque du Soleil of Golgi membrane dynamics

OpenAIRE

Bankaitis, Vytas A.

2009-01-01

The role of lipid metabolic enzymes in Golgi membrane remodeling is a subject of intense interest. Now, in this issue, Schmidt and Brown (2009. J. Cell Biol. doi:10.1083/jcb.200904147) report that lysophosphatidic acid?specific acyltransferase, LPAAT3, contributes to Golgi membrane dynamics by suppressing tubule formation.

Depletion of the human N-terminal acetyltransferase hNaa30 disrupts Golgi integrity and ARFRP1 localization.

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Starheim, Kristian K; Kalvik, Thomas V; Bjørkøy, Geir; Arnesen, Thomas

2017-04-30

The organization of the Golgi apparatus (GA) is tightly regulated. Golgi stack scattering is observed in cellular processes such as apoptosis and mitosis, and has also been associated with disruption of cellular lipid metabolism and neurodegenerative diseases. Our studies show that depletion of the human N-α-acetyltransferase 30 (hNaa30) induces fragmentation of the Golgi stack in HeLa and CAL-62 cell lines. The GA associated GTPase ADP ribosylation factor related protein 1 (ARFRP1) was previously shown to require N-terminal acetylation for membrane association and based on its N-terminal sequence, it is likely to be a substrate of hNaa30. ARFRP1 is involved in endosome-to- trans -Golgi network (TGN) traffic. We observed that ARFRP1 shifted from a predominantly cis -Golgi and TGN localization to localizing both Golgi and non-Golgi vesicular structures in hNaa30-depleted cells. However, we did not observe loss of membrane association of ARFRP1. We conclude that hNaa30 depletion induces Golgi scattering and induces aberrant ARFRP1 Golgi localization. © 2017 The Author(s).

Mitotic phosphorylation of VCIP135 blocks p97ATPase-mediated Golgi membrane fusion

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Totsukawa, Go; Matsuo, Ayaka; Kubota, Ayano; Taguchi, Yuya; Kondo, Hisao, E-mail: hk228@med.kyushu-u.ac.jp

2013-04-05

Highlights: •VCIP135 is mitotically phosphorylated on Threonine-760 and Serine-767 by Cdc2. •Phosphorylated VCIP135 does not bind to p97ATPase. •The phosphorylation of VCIP135 inhibits p97ATPase-mediated Golgi membrane fusion. -- Abstract: In mammals, the Golgi apparatus is disassembled early mitosis and reassembled at the end of mitosis. For Golgi disassembly, membrane fusion needs to be blocked. Golgi biogenesis requires two distinct p97ATPase-mediated membrane fusion, the p97/p47 and p97/p37 pathways. We previously reported that p47 phosphorylation on Serine-140 and p37 phosphorylation on Serine-56 and Threonine-59 result in mitotic inhibition of the p97/p47 and the p97/p37 pathways, respectively [11,14]. In this study, we show another mechanism of mitotic inhibition of p97-mediated Golgi membrane fusion. We clarified that VCIP135, an essential factor in both p97 membrane fusion pathways, is phosphorylated on Threonine-760 and Serine-767 by Cdc2 at mitosis and that this phosphorylated VCIP135 does not bind to p97. An in vitro Golgi reassembly assay revealed that VCIP135(T760E, S767E), which mimics mitotic phosphorylation, caused no cisternal regrowth. Our results indicate that the phosphorylation of VCIP135 on Threonine-760 and Serine-767 inhibits p97-mediated Golgi membrane fusion at mitosis.

Regulation of ER-Golgi Transport Dynamics by GTPases in Budding Yeast

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Yasuyuki Suda

2018-01-01

Full Text Available A large number of proteins are synthesized de novo in the endoplasmic reticulum (ER. They are transported through the Golgi apparatus and then delivered to their proper destinations. The ER and the Golgi play a central role in protein processing and sorting and show dynamic features in their forms. Ras super family small GTPases mediate the protein transport through and between these organelles. The ER-localized GTPase, Sar1, facilitates the formation of COPII transport carriers at the ER exit sites (ERES on the ER for the transport of cargo proteins from the ER to the Golgi. The Golgi-localized GTPase, Arf1, controls intra-Golgi, and Golgi-to-ER transport of cargo proteins by the formation of COPI carriers. Rab GTPases localized at the Golgi, which are responsible for fusion of membranes, are thought to establish the identities of compartments. Recent evidence suggests that these small GTPases regulate not only discrete sites for generation/fusion of transport carriers, but also membrane dynamics of the organelles where they locate to ensure the integrity of transport. Here we summarize the current understandings about the membrane traffic between these organelles and highlight the cutting-edge advances from super-resolution live imaging of budding yeast, Saccharomyces cerevisiae.

Golgi coiled-coil proteins contain multiple binding sites for Rab family G proteins

NARCIS (Netherlands)

Sinka, Rita; Gillingham, Alison K.; Kondylis, Vangelis; Munro, Sean

2008-01-01

Vesicles and other carriers destined for the Golgi apparatus must be guided to the correct cisternae. Golgins, long coiled-coil proteins that localize to particular Golgi subdomains via their C termini, are candidate regulators of vesicle sorting. In this study, we report that the GRIP domain

The Arf-GDP-regulated recruitment of GBF1 to Golgi membranes requires domains HDS1 and HDS2 and a Golgi-localized protein receptor.

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Quilty, Douglas; Chan, Calvin J; Yurkiw, Katherine; Bain, Alexandra; Babolmorad, Ghazal; Melançon, Paul

2018-04-19

We previously proposed a novel mechanism by which the enzyme Golgi-specific Brefeldin A resistance factor 1 (GBF1) is recruited to the membranes of the cis -Golgi, based on in vivo experiments. Here, we extended our in vivo analysis on the production of regulatory Arf-GDP and observed that ArfGAP2 and ArfGAP3 do not play a role in GBF1 recruitment. We confirm that Arf-GDP localization is critical, as a TGN-localized Arf-GDP mutant protein fails to promote GBF1 recruitment. We also reported the establishment of an in vitro GBF1 recruitment assay that supports the regulation of GBF1 recruitment by Arf-GDP. This in vitro assay yielded further evidence for the requirement of a Golgi-localized protein because heat denaturation or protease treatment of Golgi membranes abrogated GBF1 recruitment. Finally, combined in vivo and in vitro measurements indicated that the recruitment to Golgi membranes via a putative receptor requires only the HDS1 and HDS2 domains in the C-terminal half of GBF1. © 2018. Published by The Company of Biologists Ltd.

Journeys through the Golgi--taking stock in a new era.

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Emr, Scott; Glick, Benjamin S; Linstedt, Adam D; Lippincott-Schwartz, Jennifer; Luini, Alberto; Malhotra, Vivek; Marsh, Brad J; Nakano, Akihiko; Pfeffer, Suzanne R; Rabouille, Catherine; Rothman, James E; Warren, Graham; Wieland, Felix T

2009-11-16

The Golgi apparatus is essential for protein sorting and transport. Many researchers have long been fascinated with the form and function of this organelle. Yet, despite decades of scrutiny, the mechanisms by which proteins are transported across the Golgi remain controversial. At a recent meeting, many prominent Golgi researchers assembled to critically evaluate the core issues in the field. This report presents the outcome of their discussions and highlights the key open questions that will help guide the field into a new era.

Induced oligomerization targets Golgi proteins for degradation in lysosomes.

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Tewari, Ritika; Bachert, Collin; Linstedt, Adam D

2015-12-01

Manganese protects cells against forms of Shiga toxin by down-regulating the cycling Golgi protein GPP130. Down-regulation occurs when Mn binding causes GPP130 to oligomerize and traffic to lysosomes. To determine how GPP130 is redirected to lysosomes, we tested the role of GGA1 and clathrin, which mediate sorting in the canonical Golgi-to-lysosome pathway. GPP130 oligomerization was induced using either Mn or a self-interacting version of the FKBP domain. Inhibition of GGA1 or clathrin specifically blocked GPP130 redistribution, suggesting recognition of the aggregated GPP130 by the GGA1/clathrin-sorting complex. Unexpectedly, however, GPP130's cytoplasmic domain was not required, and redistribution also occurred after removal of GPP130 sequences needed for its normal cycling. Therefore, to test whether aggregate recognition might be a general phenomenon rather than one involving a specific GPP130 determinant, we induced homo-oligomerization of two unrelated Golgi-targeted constructs using the FKBP strategy. These were targeted to the cis- and trans-Golgi, respectively, using domains from mannosidase-1 and galactosyltransferase. Significantly, upon oligomerization, each redistributed to peripheral punctae and was degraded. This occurred in the absence of detectable UPR activation. These findings suggest the unexpected presence of quality control in the Golgi that recognizes aggregated Golgi proteins and targets them for degradation in lysosomes. © 2015 Tewari et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Golgi organization and the apical extension of fungal hyphae: an essential relationship.

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Harris, Steven D

2013-07-01

The Golgi apparatus performs crucial functions in the sorting and processing of proteins destined for secretion from eukaryotic cells. In filamentous fungi, organization of the Golgi apparatus reflects the unique challenges brought about by the highly polarized nature of hyphal growth. Recent results show that Golgi compartments are spatially segregated within hyphal tip cells in a manner that depends upon the integrity of the cytoskeleton. Moreover, loss of normal Golgi organization stops polarized hyphal extension and triggers de-polarization of the hyphal tip. These results emphasize the point that a spatially organized and dynamic Golgi apparatus represents an adaptation that is as important for hyphal extension as is the presence of a Spitzenkörper. In addition, they also identify regulatory mechanisms that could enable controlled de-polarization of hyphae during development or infection-related morphogenesis. © 2013 John Wiley & Sons Ltd.

Nerve growth factor induced changes in the Golgi apparatus of PC-12 rat pheochromocytoma cells as studied by ligand endocytosis, cytochemical and morphometric methods.

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Hickey, W F; Stieber, A; Hogue-Angeletti, R; Gonatas, J; GOnatas, N K

1983-10-01

Cells of the PC-12 rat pheochromocytoma cell line respond to nerve growth factor (NGF) by sprouting neurites and biochemically differentiating into sympathetic ganglion-like cells. NGF-stimulated ('differentiated') and unstimulated ('undifferentiated') cells were studied by cytochemical techniques for the localization of the enzymes acid phosphatase (ACPase) and thiamine pyrophosphatase (TPPase), and by a morphometric analysis of the distribution of endocytosed wheat-germ agglutinin labelled with horseradish peroxidase (WGA-HRP). Both cytochemical stains showed the enzymes to be distributed in lysosomes and certain cisternae of the Golgi apparatus in both NGF stimulated and unstimulated cells. ACPase was not confined to GERL (Golgi-endoplasmic reticulum-lysosome) as in certain other cells. The morphometric studies demonstrated that the reaction product of the internalized WGA-HRP occupied 4.7% of the cytoplasmic area in unstimulated cells and 4.5% in NGF-stimulated ones. Despite this similarity, the distribution of the WGA-HRP among the studied intracellular compartments in these two cell groups varied. In the NGF-stimulated cells 3.3% of the WGA-HRP reaction product was found in the innermost Golgi cisterna(e) while in unstimulated cells only 0.3% was seen in this compartment. Similarly, 4.3% of the WGA-HRP stain was found in small vesicles at the 'trans' aspect of the Golgi apparatus in stimulated cells, when only 0.3% of the stain occupied this compartment in 'undifferentiated' cells. The morphometric analysis also revealed that when the PC-12 cells were stimulated with NGF, the Golgi apparatus increased in area by approximately 70%. These findings are consistent with the hypothesis that NGF induced differentiation of PC-12 cells is coupled with enhanced endocytosis of WGA and probably of its 'receptor' to the innermost Golgi cisterna(e) and the closely associated vesicles.

Synthesis of cell wall xylans and glucans by golgi membranes

International Nuclear Information System (INIS)

Gibeaut, D.M.; Carpita, N.C.

1989-01-01

We investigated the biosynthesis of mixed-linkage β-D-glucan and glucuronoarabinoxylans which make up the hemicellulosic matrix of the primary cell walls of maize and other cereal grasses. The Golgi apparatus was enriched from plasma membrane and other organelles by flotation density gradient centrifugation. Glucan synthase I and II, which are established markers for Golgi and plasma membrane, respectively, displayed considerable overlap in conventional separations with sucrose density gradients. Flotation gradients improved separation of the membranes substantially, but the different synthases themselves also incorporated radioactivity from either 10 μM or 1 mM UDP-[ 14 C]-glucose into polymer. Relative incorporation of radioactivity into polymers from UDP-[ 14 C]-xylose by the various membrane fractions was nearly identical to relative IDPase activities, indicating that combined xylosyl transferase-xylan synthase represents a new, unequivocal marker for the Golgi apparatus. We also have developed techniques of gas-liquid chromatography and radiogas proportional counting to achieve capillary quality separation of partially methylated alditol acetates with simultaneous determination of radioactivity in the derivatives. Digestion of polymeric products by specific endo-glycanohydrolases to diagnostic oligosaccharides also reveal specific kinds of polysaccharides synthesized by the Golgi membranes. A combination of these techniques provides unequivocal determination of the linkage structure of specific polymers synthesized by the purified Golgi apparatus

Cholesterol depletion of enterocytes. Effect on the Golgi complex and apical membrane trafficking

DEFF Research Database (Denmark)

Hansen, Gert Helge; Niels-Christiansen, L L; Thorsen, Evy

2000-01-01

Intestinal brush border enzymes, including aminopeptidase N and sucrase-isomaltase, are associated with "rafts" (membrane microdomains rich in cholesterol and sphingoglycolipids). To assess the functional role of rafts in the present work, we studied the effect of cholesterol depletion on apical......, the rates of the Golgi-associated complex glycosylation and association with rafts of newly synthesized aminopeptidase N were reduced, and less of the enzyme had reached the brush border membrane after 2 h of labeling. In contrast, the basolateral Na(+)/K(+)-ATPase was neither missorted nor raft......-associated. Our results implicate the Golgi complex/trans-Golgi network in raft formation and suggest a close relationship between this event and apical membrane trafficking....

Proteomic characterization of golgi membranes enriched from Arabidopsis suspension cell cultures

DEFF Research Database (Denmark)

Hansen, Sara Fasmer; Ebert, Berit; Rautengarten, Carsten

2016-01-01

The plant Golgi apparatus has a central role in the secretory pathway and is the principal site within the cell for the assembly and processing of macromolecules. The stacked membrane structure of the Golgi apparatus along with its interactions with the cytoskeleton and endoplasmic reticulum has...... historically made the isolation and purification of this organelle difficult. Density centrifugation has typically been used to enrich Golgi membranes from plant microsomal preparations, and aside from minor adaptations, the approach is still widely employed. Here we outline the enrichment of Golgi membranes...... from an Arabidopsis cell suspension culture that can be used to investigate the proteome of this organelle. We also provide a useful workflow for the examination of proteomic data as the result of multiple analyses. Finally, we highlight a simple technique to validate the subcellular localization...

Role of the AP-5 adaptor protein complex in late endosome-to-Golgi retrieval.

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Jennifer Hirst

2018-01-01

Full Text Available The AP-5 adaptor protein complex is presumed to function in membrane traffic, but so far nothing is known about its pathway or its cargo. We have used CRISPR-Cas9 to knock out the AP-5 ζ subunit gene, AP5Z1, in HeLa cells, and then analysed the phenotype by subcellular fractionation profiling and quantitative mass spectrometry. The retromer complex had an altered steady-state distribution in the knockout cells, and several Golgi proteins, including GOLIM4 and GOLM1, were depleted from vesicle-enriched fractions. Immunolocalisation showed that loss of AP-5 led to impaired retrieval of the cation-independent mannose 6-phosphate receptor (CIMPR, GOLIM4, and GOLM1 from endosomes back to the Golgi region. Knocking down the retromer complex exacerbated this phenotype. Both the CIMPR and sortilin interacted with the AP-5-associated protein SPG15 in pull-down assays, and we propose that sortilin may act as a link between Golgi proteins and the AP-5/SPG11/SPG15 complex. Together, our findings suggest that AP-5 functions in a novel sorting step out of late endosomes, acting as a backup pathway for retromer. This provides a mechanistic explanation for why mutations in AP-5/SPG11/SPG15 cause cells to accumulate aberrant endolysosomes, and highlights the role of endosome/lysosome dysfunction in the pathology of hereditary spastic paraplegia and other neurodegenerative disorders.

Characterization of the human GARP (Golgi associated retrograde protein) complex

International Nuclear Information System (INIS)

Liewen, Heike; Meinhold-Heerlein, Ivo; Oliveira, Vasco; Schwarzenbacher, Robert; Luo Guorong; Wadle, Andreas; Jung, Martin; Pfreundschuh, Michael; Stenner-Liewen, Frank

2005-01-01

The Golgi associated retrograde protein complex (GARP) or Vps fifty-three (VFT) complex is part of cellular inter-compartmental transport systems. Here we report the identification of the VFT tethering factor complex and its interactions in mammalian cells. Subcellular fractionation shows that human Vps proteins are found in the smooth membrane/Golgi fraction but not in the cytosol. Immunostaining of human Vps proteins displays a vesicular distribution most concentrated at the perinuclear envelope. Co-staining experiments with endosomal markers imply an endosomal origin of these vesicles. Significant accumulation of VFT complex positive endosomes is found in the vicinity of the Trans Golgi Network area. This is in accordance with a putative role in Golgi associated transport processes. In Saccharomyces cerevisiae, GARP is the main effector of the small GTPase Ypt6p and interacts with the SNARE Tlg1p to facilitate membrane fusion. Accordingly, the human homologue of Ypt6p, Rab6, specifically binds hVps52. In human cells, the 'orphan' SNARE Syntaxin 10 is the genuine binding partner of GARP mediated by hVps52. This reveals a previously unknown function of human Syntaxin 10 in membrane docking and fusion events at the Golgi. Taken together, GARP shows significant conservation between various species but diversification and specialization result in important differences in human cells

Proteomic identification of S-nitrosylated Golgi proteins: new insights into endothelial cell regulation by eNOS-derived NO.

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Panjamaporn Sangwung

Full Text Available Endothelial nitric oxide synthase (eNOS is primarily localized on the Golgi apparatus and plasma membrane caveolae in endothelial cells. Previously, we demonstrated that protein S-nitrosylation occurs preferentially where eNOS is localized. Thus, in endothelial cells, Golgi proteins are likely to be targets for S-nitrosylation. The aim of this study was to identify S-nitrosylated Golgi proteins and attribute their S-nitrosylation to eNOS-derived nitric oxide in endothelial cells.Golgi membranes were isolated from rat livers. S-nitrosylated Golgi proteins were determined by a modified biotin-switch assay coupled with mass spectrometry that allows the identification of the S-nitrosylated cysteine residue. The biotin switch assay followed by Western blot or immunoprecipitation using an S-nitrosocysteine antibody was also employed to validate S-nitrosylated proteins in endothelial cell lysates.Seventy-eight potential S-nitrosylated proteins and their target cysteine residues for S-nitrosylation were identified; 9 of them were Golgi-resident or Golgi/endoplasmic reticulum (ER-associated proteins. Among these 9 proteins, S-nitrosylation of EMMPRIN and Golgi phosphoprotein 3 (GOLPH3 was verified in endothelial cells. Furthermore, S-nitrosylation of these proteins was found at the basal levels and increased in response to eNOS stimulation by the calcium ionophore A23187. Immunofluorescence microscopy and immunoprecipitation showed that EMMPRIN and GOLPH3 are co-localized with eNOS at the Golgi apparatus in endothelial cells. S-nitrosylation of EMMPRIN was notably increased in the aorta of cirrhotic rats.Our data suggest that the selective S-nitrosylation of EMMPRIN and GOLPH3 at the Golgi apparatus in endothelial cells results from the physical proximity to eNOS-derived nitric oxide.

Voltage-Dependent Intrinsic Bursting in Olfactory Bulb Golgi Cells

Science.gov (United States)

Pressler, R. Todd; Rozman, Peter A.; Strowbridge, Ben W.

2013-01-01

In the mammalian olfactory bulb (OB), local synaptic circuits modulate the evolving pattern of activity in mitral and tufted cells following olfactory sensory stimulation. GABAergic granule cells, the most numerous interneuron subtype in this brain region, have been extensively studied. However, classic studies using Golgi staining methods…

Physiological Roles of Plant Post-Golgi Transport Pathways in Membrane Trafficking.

Science.gov (United States)

Uemura, Tomohiro

2016-10-01

Membrane trafficking is the fundamental system through which proteins are sorted to their correct destinations in eukaryotic cells. Key regulators of this system include RAB GTPases and soluble N-ethylmaleimide sensitive factor attachment protein receptors (SNAREs). Interestingly, the numbers of RAB GTPases and SNAREs involved in post-Golgi transport pathways in plant cells are larger than those in animal and yeast cells, suggesting that plants have evolved unique and complex post-Golgi transport pathways. The trans-Golgi network (TGN) is an important organelle that acts as a sorting station in the post-Golgi transport pathways of plant cells. The TGN also functions as the early endosome, which is the first compartment to receive endocytosed proteins. Several endocytosed proteins on the plasma membrane (PM) are initially targeted to the TGN/EE, then recycled back to the PM or transported to the vacuole for degradation. The recycling and degradation of the PM localized proteins is essential for the development and environmental responses in plant. The present review describes the post-Golgi transport pathways that show unique physiological functions in plants. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Inheritance of the Golgi Apparatus and Cytokinesis Are Controlled by Degradation of GBF1

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Roberto Magliozzi

2018-06-01

Full Text Available Summary: Although much is known about how chromosome segregation is coupled to cell division, how intracellular organelles partition during mitotic division is poorly understood. We report that the phosphorylation-dependent degradation of the ARFGEF GBF1 regulates organelle trafficking during cell division. We show that, in mitosis, GBF1 is phosphorylated on Ser292 and Ser297 by casein kinase-2 allowing recognition by the F-box protein βTrCP. GBF1 interaction with βTrCP recruits GBF1 to the SCFβTrCP ubiquitin ligase complex, triggering its degradation. Phosphorylation and degradation of GBF1 occur along microtubules at the intercellular bridge of telophase cells and are required for Golgi membrane positioning and postmitotic Golgi reformation. Indeed, expression of a non-degradable GBF1 mutant inhibits the transport of the Golgi cluster adjacent to the midbody toward the Golgi twin positioned next to the centrosome and results in defective Golgi reassembly and cytokinesis failure. These findings define a mechanism that controls postmitotic Golgi reassembly and inheritance. : Magliozzi et al. demonstrate that, in mitosis, the ARFGEF GBF1 is targeted for ubiquitin-dependent degradation by casein kinase-2 and the SCFβTrCP ubiquitin ligase and show that GBF1 proteolysis is required for Golgi inheritance and accurate cell division. Keywords: cell division, cytokinesis, mitosis, Golgi apparatus, GBF1, ubiquitin-proteasome system, protein degradation, Cullin-RING ubiquitin ligase

Localization of three human polypeptide GalNAc-transferases in HeLa cells suggests initiation of O-linked glycosylation throughout the Golgi apparatus

DEFF Research Database (Denmark)

Röttger, S; White, J; Wandall, H H

1998-01-01

O-glycosylation of proteins is initiated by a family of UDP-N-acetylgalactosamine:polypeptide N-acetylgalactos-aminyltransferases (GalNAc-T). In this study, we have localized endogenous and epitope-tagged human GalNAc-T1, -T2 and -T3 to the Golgi apparatus in HeLa cells by subcellular fractionation......, immunofluorescence and immunoelectron microscopy. We show that all three GalNAc-transferases are concentrated about tenfold in Golgi stacks over Golgi associated tubular-vesicular membrane structures. Surprisingly, we find that GalNAc-T1, -T2 and -T3 are present throughout the Golgi stack suggesting that initiation...... of O-glycosylation may not be restricted to the cis Golgi, but occur at multiple sites within the Golgi apparatus. GalNAc-T1 distributes evenly across the Golgi stack whereas GalNAc-T2 and -T3 reside preferentially on the trans side and in the medial part of the Golgi stack, respectively. Moreover, we...

Oxysterol-binding Protein Activation at Endoplasmic Reticulum-Golgi Contact Sites Reorganizes Phosphatidylinositol 4-Phosphate Pools*

Science.gov (United States)

Goto, Asako; Charman, Mark; Ridgway, Neale D.

2016-01-01

Oxysterol-binding protein (OSBP) exchanges cholesterol and phosphatidylinositol 4-phosphate (PI-4P) at contact sites between the endoplasmic reticulum (ER) and the trans-Golgi/trans-Golgi network. 25-Hydroxycholesterol (25OH) competitively inhibits this exchange reaction in vitro and causes the constitutive localization of OSBP at the ER/Golgi interface and PI-4P-dependent recruitment of ceramide transfer protein (CERT) for sphingomyelin synthesis. We used PI-4P probes and mass analysis to determine how OSBP controls the availability of PI-4P for this metabolic pathway. Treatment of fibroblasts or Chinese hamster ovary (CHO) cells with 25OH caused a 50–70% reduction in Golgi-associated immunoreactive PI-4P that correlated with Golgi localization of OSBP. In contrast, 25OH caused an OSBP-dependent enrichment in Golgi PI-4P that was detected with a pleckstrin homology domain probe. The cellular mass of phosphatidylinositol monophosphates and Golgi PI-4P measured with an unbiased PI-4P probe (P4M) was unaffected by 25OH and OSBP silencing, indicating that OSBP shifts the distribution of PI-4P upon localization to ER-Golgi contact sites. The PI-4P and sterol binding activities of OSBP were both required for 25OH activation of sphingomyelin synthesis, suggesting that 25OH must be exchanged for PI-4P to be concentrated at contact sites. We propose a model wherein 25OH activation of OSBP promotes the binding and retention of PI-4P at ER-Golgi contact sites. This pool of PI-4P specifically recruits pleckstrin homology domain-containing proteins involved in lipid transfer and metabolism, such as CERT. PMID:26601944

Post-Golgi anterograde transport requires GARP-dependent endosome-to-TGN retrograde transport

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Hirata, Tetsuya; Fujita, Morihisa; Nakamura, Shota; Gotoh, Kazuyoshi; Motooka, Daisuke; Murakami, Yoshiko; Maeda, Yusuke; Kinoshita, Taroh

2015-01-01

The importance of endosome-to–trans-Golgi network (TGN) retrograde transport in the anterograde transport of proteins is unclear. In this study, genome-wide screening of the factors necessary for efficient anterograde protein transport in human haploid cells identified subunits of the Golgi-associated retrograde protein (GARP) complex, a tethering factor involved in endosome-to-TGN transport. Knockout (KO) of each of the four GARP subunits, VPS51–VPS54, in HEK293 cells caused severely defective anterograde transport of both glycosylphosphatidylinositol (GPI)-anchored and transmembrane proteins from the TGN. Overexpression of VAMP4, v-SNARE, in VPS54-KO cells partially restored not only endosome-to-TGN retrograde transport, but also anterograde transport of both GPI-anchored and transmembrane proteins. Further screening for genes whose overexpression normalized the VPS54-KO phenotype identified TMEM87A, encoding an uncharacterized Golgi-resident membrane protein. Overexpression of TMEM87A or its close homologue TMEM87B in VPS54-KO cells partially restored endosome-to-TGN retrograde transport and anterograde transport. Therefore GARP- and VAMP4-dependent endosome-to-TGN retrograde transport is required for recycling of molecules critical for efficient post-Golgi anterograde transport of cell-surface integral membrane proteins. In addition, TMEM87A and TMEM87B are involved in endosome-to-TGN retrograde transport. PMID:26157166

Autometallographic (AMG) technique used for enhancement of the Golgi-Cox staining gives good contrast andhigh resolution of dendrites and spines

DEFF Research Database (Denmark)

Orlowski, Dariusz

Despite the existence of many newer staining methods, Golgi staining still remains the primary method forvisualization of the dendrites and spines. The black deposit in the Golgi-Cox impregnated cells is a Mercuricsulphide, therefore autometallographic (AMG) technique which is used for visualizat...... of dendrites and spines in the rat hippocampus. The describedmethod will be of value for future behavioural-anatomical studies, examining changes in dendrite branching andspine density caused by brain diseases and their subsequent treatment.......Despite the existence of many newer staining methods, Golgi staining still remains the primary method forvisualization of the dendrites and spines. The black deposit in the Golgi-Cox impregnated cells is a Mercuricsulphide, therefore autometallographic (AMG) technique which is used...... for visualization of the metals and metalsulphides/selenides in tissue may be used to enhance the Golgi-Cox staining. We demonstrated accordingly thatuse of AMG enhancement method on the Golgi-Cox staining gives good contrast and high resolution of dendritesand spines. Moreover, this method is cheaper and more...

A role for Sar1 and ARF1 GTPases during Golgi biogenesis in the protozoan parasite Trypanosoma brucei

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Yavuz, Sevil; Warren, Graham

2017-01-01

A single Golgi stack is duplicated and partitioned into two daughter cells during the cell cycle of the protozoan parasite Trypanosoma brucei. The source of components required to generate the new Golgi and the mechanism by which it forms are poorly understood. Using photoactivatable GFP, we show that the existing Golgi supplies components directly to the newly forming Golgi in both intact and semipermeabilized cells. The movement of a putative glycosyltransferase, GntB, requires the Sar1 and ARF1 GTPases in intact cells. In addition, we show that transfer of GntB from the existing Golgi to the new Golgi can be recapitulated in semipermeabilized cells and is sensitive to the GTP analogue GTPγS. We suggest that the existing Golgi is a key source of components required to form the new Golgi and that this process is regulated by small GTPases. PMID:28495798

Nonrandom γ-TuNA-dependent spatial pattern of microtubule nucleation at the Golgi.

Science.gov (United States)

Sanders, Anna A W M; Chang, Kevin; Zhu, Xiaodong; Thoppil, Roslin J; Holmes, William R; Kaverina, Irina

2017-11-07

Noncentrosomal microtubule (MT) nucleation at the Golgi generates MT network asymmetry in motile vertebrate cells. Investigating the Golgi-derived MT (GDMT) distribution, we find that MT asymmetry arises from nonrandom nucleation sites at the Golgi (hotspots). Using computational simulations, we propose two plausible mechanistic models of GDMT nucleation leading to this phenotype. In the "cooperativity" model, formation of a single GDMT promotes further nucleation at the same site. In the "heterogeneous Golgi" model, MT nucleation is dramatically up-regulated at discrete and sparse locations within the Golgi. While MT clustering in hotspots is equally well described by both models, simulating MT length distributions within the cooperativity model fits the data better. Investigating the molecular mechanism underlying hotspot formation, we have found that hotspots are significantly smaller than a Golgi subdomain positive for scaffolding protein AKAP450, which is thought to recruit GDMT nucleation factors. We have further probed potential roles of known GDMT-promoting molecules, including γ-TuRC-mediated nucleation activator (γ-TuNA) domain-containing proteins and MT stabilizer CLASPs. While both γ-TuNA inhibition and lack of CLASPs resulted in drastically decreased GDMT nucleation, computational modeling revealed that only γ-TuNA inhibition suppressed hotspot formation. We conclude that hotspots require γ-TuNA activity, which facilitates clustered GDMT nucleation at distinct Golgi sites. © 2017 Sanders et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

The cerebellar Golgi cell and spatiotemporal organization of granular layer activity

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Egidio eD‘Angelo

2013-05-01

Full Text Available The cerebellar granular layer has been suggested to perform a complex spatiotemporal reconfiguration of incoming mossy fiber signals. Central to this role is the inhibitory action exerted by Golgi cells over granule cells: Golgi cells inhibit granule cells through double feedforward and feedback inhibitory loops and generate a broad lateral inhibition that extends beyond the afferent synaptic field. This characteristic connectivity has recently been investigated in great detail and been correlated with specific functional properties of the neuron. These include theta-frequency pacemaking, network entrainment into coherent oscillations and phase resetting. Important advances have also been made in terms of determining the membrane and synaptic properties of the neuron, and clarifying the mechanisms of activation by input bursts. Moreover, voltage sensitive dye imaging and multi-electrode array recordings, combined with mathematical simulations based on realistic computational models, have improved our understanding of the impact of Golgi cell activity on granular layer circuit computations. These investigations have highlighted the critical role of Golgi cells in: generating dense clusters of granule cell activity organized in center-surround structures, implementing combinatorial operations on multiple mossy fiber inputs, regulating transmission gain and cut-off frequency, controlling spike timing and burst transmission, and determining the sign, intensity and extension of long-term synaptic plasticity at the mossy fiber-granule cell relay. This review considers recent advances in the field, highlighting the functional implications of Golgi cells for granular layer network computation and indicating new challenges for cerebellar research.

Oxysterol-binding Protein Activation at Endoplasmic Reticulum-Golgi Contact Sites Reorganizes Phosphatidylinositol 4-Phosphate Pools.

Science.gov (United States)

Goto, Asako; Charman, Mark; Ridgway, Neale D

2016-01-15

Oxysterol-binding protein (OSBP) exchanges cholesterol and phosphatidylinositol 4-phosphate (PI-4P) at contact sites between the endoplasmic reticulum (ER) and the trans-Golgi/trans-Golgi network. 25-Hydroxycholesterol (25OH) competitively inhibits this exchange reaction in vitro and causes the constitutive localization of OSBP at the ER/Golgi interface and PI-4P-dependent recruitment of ceramide transfer protein (CERT) for sphingomyelin synthesis. We used PI-4P probes and mass analysis to determine how OSBP controls the availability of PI-4P for this metabolic pathway. Treatment of fibroblasts or Chinese hamster ovary (CHO) cells with 25OH caused a 50-70% reduction in Golgi-associated immunoreactive PI-4P that correlated with Golgi localization of OSBP. In contrast, 25OH caused an OSBP-dependent enrichment in Golgi PI-4P that was detected with a pleckstrin homology domain probe. The cellular mass of phosphatidylinositol monophosphates and Golgi PI-4P measured with an unbiased PI-4P probe (P4M) was unaffected by 25OH and OSBP silencing, indicating that OSBP shifts the distribution of PI-4P upon localization to ER-Golgi contact sites. The PI-4P and sterol binding activities of OSBP were both required for 25OH activation of sphingomyelin synthesis, suggesting that 25OH must be exchanged for PI-4P to be concentrated at contact sites. We propose a model wherein 25OH activation of OSBP promotes the binding and retention of PI-4P at ER-Golgi contact sites. This pool of PI-4P specifically recruits pleckstrin homology domain-containing proteins involved in lipid transfer and metabolism, such as CERT. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

COPI-mediated retrograde trafficking from the Golgi to the ER regulates EGFR nuclear transport

International Nuclear Information System (INIS)

Wang, Ying-Nai; Wang, Hongmei; Yamaguchi, Hirohito; Lee, Hong-Jen; Lee, Heng-Huan; Hung, Mien-Chie

2010-01-01

Research highlights: → ARF1 activation is involved in the EGFR transport to the ER and the nucleus. → Assembly of γ-COP coatomer mediates EGFR transport to the ER and the nucleus. → Golgi-to-ER retrograde trafficking regulates nuclear transport of EGFR. -- Abstract: Emerging evidence indicates that cell surface receptors, such as the entire epidermal growth factor receptor (EGFR) family, have been shown to localize in the nucleus. A retrograde route from the Golgi to the endoplasmic reticulum (ER) is postulated to be involved in the EGFR trafficking to the nucleus; however, the molecular mechanism in this proposed model remains unexplored. Here, we demonstrate that membrane-embedded vesicular trafficking is involved in the nuclear transport of EGFR. Confocal immunofluorescence reveals that in response to EGF, a portion of EGFR redistributes to the Golgi and the ER, where its NH 2 -terminus resides within the lumen of Golgi/ER and COOH-terminus is exposed to the cytoplasm. Blockage of the Golgi-to-ER retrograde trafficking by brefeldin A or dominant mutants of the small GTPase ADP-ribosylation factor, which both resulted in the disassembly of the coat protein complex I (COPI) coat to the Golgi, inhibit EGFR transport to the ER and the nucleus. We further find that EGF-dependent nuclear transport of EGFR is regulated by retrograde trafficking from the Golgi to the ER involving an association of EGFR with γ-COP, one of the subunits of the COPI coatomer. Our findings experimentally provide a comprehensive pathway that nuclear transport of EGFR is regulated by COPI-mediated vesicular trafficking from the Golgi to the ER, and may serve as a general mechanism in regulating the nuclear transport of other cell surface receptors.

CCDC115 Deficiency Causes a Disorder of Golgi Homeostasis with Abnormal Protein Glycosylation

NARCIS (Netherlands)

Jansen, Jos C.; Cirak, Sebahattin; van Scherpenzeel, Monique; Timal, Sharita; Reunert, Janine; Rust, Stephan; Pérez, Belén; Vicogne, Dorothée; Krawitz, Peter; Wada, Yoshinao; Ashikov, Angel; Pérez-Cerdá, Celia; Medrano, Celia; Arnoldy, Andrea; Hoischen, Alexander; Huijben, Karin; Steenbergen, Gerry; Quelhas, Dulce; Diogo, Luisa; Rymen, Daisy; Jaeken, Jaak; Guffon, Nathalie; Cheillan, David; van den Heuvel, Lambertus P.; Maeda, Yusuke; Kaiser, Olaf; Schara, Ulrike; Gerner, Patrick; van den Boogert, Marjolein A. W.; Holleboom, Adriaan G.; Nassogne, Marie-Cécile; Sokal, Etienne; Salomon, Jody; van den Bogaart, Geert; Drenth, Joost P. H.; Huynen, Martijn A.; Veltman, Joris A.; Wevers, Ron A.; Morava, Eva; Matthijs, Gert; Foulquier, François; Marquardt, Thorsten; Lefeber, Dirk J.

2016-01-01

Disorders of Golgi homeostasis form an emerging group of genetic defects. The highly heterogeneous clinical spectrum is not explained by our current understanding of the underlying cell-biological processes in the Golgi. Therefore, uncovering genetic defects and annotating gene function are

Pathological changes of Golgi complex in hemocytoblasts of spleen of young axolotls after x-irradiation

Energy Technology Data Exchange (ETDEWEB)

Turska, R.

1975-01-01

The data available up to now concerning the structure of Golgi complex in different types of normal and pathologically changed cells are very divergent. Results are reported from detailed studies on changes occurring within the Golgi complex in the spleen of three-month old axolotls after x-ray irradiation with a single dose of 1,200 R and killed by decapitation 15, 30, 60 minutes and 3, 6, and 12 hours after irradiation.

Membrane topology of Golgi-localized probable S-adenosylmethionine-dependent methyltransferase in tobacco (Nicotiana tabacum) BY-2 cells.

Science.gov (United States)

Liu, Jianping; Hayashi, Kyoko; Matsuoka, Ken

2015-01-01

S-adenosylmethionine (SAM)-dependent methyltransferases (MTases) transfer methyl groups to substrates. In this study, a novel putative tobacco SAM-MTase termed Golgi-localized methyl transferase 1 (GLMT1) has been characterized. GLMT1 is comprised of 611 amino acids with short N-terminal region, putative transmembrane region, and C-terminal SAM-MTase domain. Expression of monomeric red fluorescence protein (mRFP)-tagged protein in tobacco BY-2 cell indicated that GLMT1 is a Golgi-localized protein. Analysis of the membrane topology by protease digestion suggested that both C-terminal catalytic region and N-terminal region seem to be located to the cytosolic side of the Golgi apparatus. Therefore, GLMT1 might have a different function than the previously studied SAM-MTases in plants.

Identification of a Golgi apparatus protein complex important for the asexual erythrocytic cycle of the malaria parasite Plasmodium falciparum.

Science.gov (United States)

Hallée, Stéphanie; Thériault, Catherine; Gagnon, Dominic; Kehrer, Jessica; Frischknecht, Friedrich; Mair, Gunnar R; Richard, Dave

2018-03-26

Compared with other eukaryotic cell types, malaria parasites appear to possess a more rudimentary Golgi apparatus being composed of dispersed, unstacked cis and trans-cisternae. Despite playing a central role in the secretory pathway of the parasite, few Plasmodium Golgi resident proteins have been characterised. We had previously identified a new Golgi resident protein of unknown function, which we had named Golgi Protein 1, and now show that it forms a complex with a previously uncharacterised transmembrane protein (Golgi Protein 2, GP2). The Golgi Protein complex localises to the cis-Golgi throughout the erythrocytic cycle and potentially also during the mosquito stages. Analysis of parasite strains where GP1 expression is conditionally repressed and/or the GP2 gene is inactivated reveals that though the Golgi protein complex is not essential at any stage of the parasite life cycle, it is important for optimal asexual development in the blood stages. © 2018 John Wiley & Sons Ltd.

The Golgin GMAP210/TRIP11 anchors IFT20 to the Golgi complex.

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John A Follit

2008-12-01

Full Text Available Eukaryotic cells often use proteins localized to the ciliary membrane to monitor the extracellular environment. The mechanism by which proteins are sorted, specifically to this subdomain of the plasma membrane, is almost completely unknown. Previously, we showed that the IFT20 subunit of the intraflagellar transport particle is localized to the Golgi complex, in addition to the cilium and centrosome, and hypothesized that the Golgi pool of IFT20 plays a role in sorting proteins to the ciliary membrane. Here, we show that IFT20 is anchored to the Golgi complex by the golgin protein GMAP210/Trip11. Mice lacking GMAP210 die at birth with a pleiotropic phenotype that includes growth restriction, ventricular septal defects of the heart, omphalocele, and lung hypoplasia. Cells lacking GMAP210 have normal Golgi structure, but IFT20 is no longer localized to this organelle. GMAP210 is not absolutely required for ciliary assembly, but cilia on GMAP210 mutant cells are shorter than normal and have reduced amounts of the membrane protein polycystin-2 localized to them. This work suggests that GMAP210 and IFT20 function together at the Golgi in the sorting or transport of proteins destined for the ciliary membrane.

Galacturonomannan and Golgi-derived membrane linked to growth and shaping of biogenic calcite

Science.gov (United States)

Marsh, M. E.; Ridall, A. L.; Azadi, P.; Duke, P. J.

2002-01-01

The coccolithophores are valuable models for the design and synthesis of composite materials, because the cellular machinery controlling the nucleation, growth, and patterning of their calcitic scales (coccoliths) can be examined genetically. The coccoliths are formed within the Golgi complex and are the major CaCO(3) component in limestone sediments-particularly those of the Cretaceous period. In this study, we describe mutants lacking a sulfated galacturonomannan and show that this polysaccharide in conjunction with the Golgi-derived membrane is directly linked to the growth and shaping of coccolith calcite but not to the initial orientated nucleation of the mineral phase.

Defects in the COG complex and COG-related trafficking regulators affect neuronal Golgi function.

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Leslie K Climer

2015-10-01

Full Text Available The Conserved Oligomeric Golgi (COG complex is an evolutionarily conserved hetero-octameric protein complex that has been proposed to organize vesicle tethering at the Golgi apparatus. Defects in seven of the eight COG subunits are linked to Congenital Disorders of Glycosylation (CDG-type II, a family of rare diseases involving misregulation of protein glycosylation, alterations in Golgi structure, variations in retrograde trafficking through the Golgi and system-wide clinical pathologies. A troublesome aspect of these diseases are the neurological pathologies such as low IQ, microcephaly and cerebellar atrophy. The essential function of the COG complex is dependent upon interactions with other components of trafficking machinery, such as Rab-GTPases and SNAREs. COG-interacting Rabs and SNAREs have been implicated in neurodegenerative diseases like Alzheimer’s disease and Parkinson’s disease. Defects in Golgi maintenance disrupts trafficking and processing of essential proteins, frequently associated with and contributing to compromised neuron function and human disease. Despite the recent advances in molecular neuroscience, the subcellular bases for most neurodegenerative diseases are poorly understood. This article gives an overview of the potential contributions of the COG complex and its Rab and SNARE partners in the pathogenesis of different neurodegenerative disorders.

Transport of soluble proteins through the Golgi occurs by diffusion via continuities across cisternae

Science.gov (United States)

Beznoussenko, Galina V; Parashuraman, Seetharaman; Rizzo, Riccardo; Polishchuk, Roman; Martella, Oliviano; Di Giandomenico, Daniele; Fusella, Aurora; Spaar, Alexander; Sallese, Michele; Capestrano, Maria Grazia; Pavelka, Margit; Vos, Matthijn R; Rikers, Yuri GM; Helms, Volkhard; Mironov, Alexandre A; Luini, Alberto

2014-01-01

The mechanism of transport through the Golgi complex is not completely understood, insofar as no single transport mechanism appears to account for all of the observations. Here, we compare the transport of soluble secretory proteins (albumin and α1-antitrypsin) with that of supramolecular cargoes (e.g., procollagen) that are proposed to traverse the Golgi by compartment progression–maturation. We show that these soluble proteins traverse the Golgi much faster than procollagen while moving through the same stack. Moreover, we present kinetic and morphological observations that indicate that albumin transport occurs by diffusion via intercisternal continuities. These data provide evidence for a transport mechanism that applies to a major class of secretory proteins and indicate the co-existence of multiple intra-Golgi trafficking modes. DOI: http://dx.doi.org/10.7554/eLife.02009.001 PMID:24867214

Live-cell imaging of post-golgi transport vesicles in cultured hippocampal neurons

DEFF Research Database (Denmark)

Jensen, Camilla Stampe; Misonou, Hiroaki

2015-01-01

compartments of neurons. In the past two decades, the establishment and advancement of fluorescent protein technology have provided us with opportunities to study how proteins are trafficked in living cells. However, live imaging of trafficking processes in neurons necessitate imaging tools to distinguish...... the several different routes that neurons use for protein trafficking. Here we provide a novel protocol to selectively visualize post-Golgi transport vesicles carrying fluorescent-labeled ion channel proteins in living neurons. Further, we provide a number of analytical tools we developed to quantify...... mechanisms by which post-Golgi vesicles are trafficked in neurons. Our protocol uniquely combines the classic temperature-block with close monitoring of the transient expression of transfected protein tagged with fluorescent proteins, and provides a quick and easy way to study protein trafficking in living...

PERMANGANATE FIXATION OF THE GOLGI COMPLEX AND OTHER CYTOPLASMIC STRUCTURES OF MAMMALIAN TESTES

Science.gov (United States)

Mollenhauer, Hilton H.; Zebrun, William

1960-01-01

Observations on the fine structure of KMnO4-fixed testes of small mammals (guinea pig, rat, and mouse) reveal certain morphological differences between the spermatogenic and Sertoli cells which have not been demonstrated in the same tissue fixed with OsO4. Aggregates of minute circular profiles, much smaller than the spherical Golgi vesicles, are described in close association with the Golgi complex of developing spermatids. Groups of dense flattened vesicles, individually surrounded by a membrane of different dimensions than that which bounds most of the other cell organelles, appear dispersed within the cytoplasm of some spermatogenic cells. Flattened vesicles of greater density than those belonging to the Golgi complex are reported confined to the inner Golgi zone of developing guinea pig spermatids between the Golgi cisternae and the head cap. The profiles of endoplasmic reticulum within spermatocytes appear shorter, wider, and more tortuous than those of Sertoli cells. Minute cytoplasmic particles approximately 300 A in diameter and of high electron opacity appear randomly disposed in some Sertoli cells. Groups of irregular-shaped ovoid bodies within the developing spermatids are described as resembling portions of cytoplasm from closely adjacent spermatids. Interpretation is presented regarding the fine structure of KMnO4-fixed testes in view of what has already been reported for mammalian testes fixed in OsO4. PMID:13771855

Oxysterol-binding Protein Activation at Endoplasmic Reticulum-Golgi Contact Sites Reorganizes Phosphatidylinositol 4-Phosphate Pools*

OpenAIRE

Goto, Asako; Charman, Mark; Ridgway, Neale D.

2015-01-01

Oxysterol-binding protein (OSBP) exchanges cholesterol and phosphatidylinositol 4-phosphate (PI-4P) at contact sites between the endoplasmic reticulum (ER) and the trans-Golgi/trans-Golgi network. 25-Hydroxycholesterol (25OH) competitively inhibits this exchange reaction in vitro and causes the constitutive localization of OSBP at the ER/Golgi interface and PI-4P-dependent recruitment of ceramide transfer protein (CERT) for sphingomyelin synthesis. We used PI-4P probes and mass analysis to de...

Vibration sensitivity of human muscle spindles and Golgi tendon organs.

Science.gov (United States)

Fallon, James B; Macefield, Vaughan G

2007-07-01

The responses of the various muscle receptors to vibration are more complicated than a naïve categorization into stretch (muscle spindle primary ending), length (muscle spindle secondary endings), and tension (Golgi tendon organs) receptors. To emphasize the similarity of responses to small length changes, we recorded from 58 individual muscle afferents subserving receptors in the ankle or toe dorsiflexors of awake human subjects (32 primary endings, 20 secondary endings, and six Golgi tendon organs). Transverse sinusoidal vibration was applied to the distal tendon of the receptor-bearing muscle, while subjects either remained completely relaxed or maintained a weak isometric contraction of the appropriate muscle. In relaxed muscle, few units responded in a 1:1 manner to vibration, and there was no evidence of a preferred frequency of activation. In active muscle the response profiles of all three receptor types overlapped, with no significant difference in threshold between receptor types. These results emphasize that when intramuscular tension increases during a voluntary contraction, Golgi tendon organs and muscle spindle secondary endings, not just muscle spindle primary endings, can effectively encode small imposed length changes.

La técnica de impregnación argéntica de Golgi. Conmemoración del centenario del premio nobel de Medicina (1906 compartido por Camillo Golgi y Santiago Ramón y Cajal

Directory of Open Access Journals (Sweden)

Orlando Torres-Fernández

2006-12-01

Full Text Available La técnica de Golgi es un sencillo procedimiento histológico que revela la morfología neuronal completa en tres dimensiones. Este método se fundamenta en la formación de depósitos opacos intracelulares de cromato argéntico, producto de la reacción entre el bicromato de potasio y el nitrato de plata (reacción negra. Camillo Golgi, su descubridor, y Santiago Ramón y Cajal, su principal exponente, recibieron el premio nobel de Medicina y Fisiología en 1906 por su contribución al conocimiento de la estructura del sistema nervioso. Gran parte de sus logros se obtuvieron a través de la aplicación del método de impregnación argéntica. Sin embargo, Golgi y Cajal tenían interpretaciones diferentes sobre la estructura del tejido nervioso. Golgi era defensor de la teoría reticular, la cual proponía que el sistema nervioso estaba conformado por una red de células fusionadas a través de los axones a manera de un sincitio. Por el contrario, la doctrina neuronal, defendida por Cajal, sostenía que las neuronas eran células independientes. También se debe a Golgi y su reazione nera el descubrimiento del organelo celular conocido como ‘aparato de Golgi'. La microscopía electrónica confirmó los postulados de la doctrina neuronal, así como la existencia del complejo de Golgi, y contribuyó al resurgimiento de la técnica de impregnación argéntica. Aunque existen métodos modernos de tinción intracelular que revelan imágenes excelentes de la morfología neuronal, la técnica de Golgi se mantiene vigente por ser un método más práctico y menos costoso para el estudio de la morfología normal y patológica de las neuronas.

Sites of sulfate incorporation into mammotrophs and somatotrophs of the rat pituitary as determined by quantitative electron microscopic autoradiography

International Nuclear Information System (INIS)

Rosenzweig, L.J.; Farquhar, M.G.

1980-01-01

Dispersed pituitary cells were labeled with [ 35 S]sulfate followed by a chase incubation in order to study sulfate incorporation and transport in anterior pituitary cells. The initial site of incorporation of sulfate, the kinetics of sulfate transport, and the intracellular localization of incorporated sulfate were studied by quantitative electron microscope autoradiography. Analysis of autoradiograms from estrogen-treated female rats revealed that all granulated cell types incorporate sulfate. The labeling index of the various cell types was greatest for mammotrophs, slightly less for corticotrophs, gonadotrophs, and thyrotrophs and least for somatotrophs. These results indicate the [ 35 S]sulfate is initially incorporated into the Golgi complex of all interior pituitary cell types. The majority of the sulfate-labeled macromolecules are then packaged into immature secretion granules in the Golgi region, which become mature granules. In addition, a considerable amount (approx. 30% in mammotrophs) of the radioactivity remains associated within the Golgi region for up to 2 h post pulse. The incorporation of sulfate into the Golgi complex and its transfer to secretory granule membranes and/or contents thus appears to be a general property of anterior pituitary cells

Foot-and-mouth disease virus-induced RNA polymerase is associated with Golgi apparatus.

OpenAIRE

Polatnick, J; Wool, S H

1985-01-01

Electrophoretic analysis of the Golgi apparatus isolated by differential centrifugation from radiolabeled cells infected with foot-and-mouth disease virus showed about 10 protein bands. The virus-induced RNA polymerase was identified by immunoprecipitation and electron microscope staining procedures. Pulse-chase experiments indicated that the polymerase passed through the Golgi apparatus in less than 1 h.

CCDC115 Deficiency Causes a Disorder of Golgi Homeostasis with Abnormal Protein Glycosylation.

Science.gov (United States)

Jansen, Jos C; Cirak, Sebahattin; van Scherpenzeel, Monique; Timal, Sharita; Reunert, Janine; Rust, Stephan; Pérez, Belén; Vicogne, Dorothée; Krawitz, Peter; Wada, Yoshinao; Ashikov, Angel; Pérez-Cerdá, Celia; Medrano, Celia; Arnoldy, Andrea; Hoischen, Alexander; Huijben, Karin; Steenbergen, Gerry; Quelhas, Dulce; Diogo, Luisa; Rymen, Daisy; Jaeken, Jaak; Guffon, Nathalie; Cheillan, David; van den Heuvel, Lambertus P; Maeda, Yusuke; Kaiser, Olaf; Schara, Ulrike; Gerner, Patrick; van den Boogert, Marjolein A W; Holleboom, Adriaan G; Nassogne, Marie-Cécile; Sokal, Etienne; Salomon, Jody; van den Bogaart, Geert; Drenth, Joost P H; Huynen, Martijn A; Veltman, Joris A; Wevers, Ron A; Morava, Eva; Matthijs, Gert; Foulquier, François; Marquardt, Thorsten; Lefeber, Dirk J

2016-02-04

Disorders of Golgi homeostasis form an emerging group of genetic defects. The highly heterogeneous clinical spectrum is not explained by our current understanding of the underlying cell-biological processes in the Golgi. Therefore, uncovering genetic defects and annotating gene function are challenging. Exome sequencing in a family with three siblings affected by abnormal Golgi glycosylation revealed a homozygous missense mutation, c.92T>C (p.Leu31Ser), in coiled-coil domain containing 115 (CCDC115), the function of which is unknown. The same mutation was identified in three unrelated families, and in one family it was compound heterozygous in combination with a heterozygous deletion of CCDC115. An additional homozygous missense mutation, c.31G>T (p.Asp11Tyr), was found in a family with two affected siblings. All individuals displayed a storage-disease-like phenotype involving hepatosplenomegaly, which regressed with age, highly elevated bone-derived alkaline phosphatase, elevated aminotransferases, and elevated cholesterol, in combination with abnormal copper metabolism and neurological symptoms. Two individuals died of liver failure, and one individual was successfully treated by liver transplantation. Abnormal N- and mucin type O-glycosylation was found on serum proteins, and reduced metabolic labeling of sialic acids was found in fibroblasts, which was restored after complementation with wild-type CCDC115. PSI-BLAST homology detection revealed reciprocal homology with Vma22p, the yeast V-ATPase assembly factor located in the endoplasmic reticulum (ER). Human CCDC115 mainly localized to the ERGIC and to COPI vesicles, but not to the ER. These data, in combination with the phenotypic spectrum, which is distinct from that associated with defects in V-ATPase core subunits, suggest a more general role for CCDC115 in Golgi trafficking. Our study reveals CCDC115 deficiency as a disorder of Golgi homeostasis that can be readily identified via screening for abnormal

Stathmin 1/2-triggered microtubule loss mediates Golgi fragmentation in mutant SOD1 motor neurons

NARCIS (Netherlands)

Bellouze, Sarah; Baillat, Gilbert; Buttigieg, Dorothée; de la Grange, Pierre; Rabouille, Catherine; Haase, Georg

2016-01-01

BACKGROUND: Pathological Golgi fragmentation represents a constant pre-clinical feature of many neurodegenerative diseases including amyotrophic lateral sclerosis (ALS) but its molecular mechanisms remain hitherto unclear. RESULTS: Here, we show that the severe Golgi fragmentation in transgenic

Inducible Inhibition of Gβγ Reveals Localization-dependent Functions at the Plasma Membrane and Golgi*

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Klayman, Lauren M.; Wedegaertner, Philip B.

2017-01-01

Heterotrimeric G proteins signal at a variety of endomembrane locations, in addition to their canonical function at the cytoplasmic surface of the plasma membrane (PM), where they are activated by cell surface G protein-coupled receptors. Here we focus on βγ signaling at the Golgi, where βγ activates a signaling cascade, ultimately resulting in vesicle fission from the trans-Golgi network (TGN). To develop a novel molecular tool for inhibiting endogenous βγ in a spatial-temporal manner, we take advantage of a lipid association mutant of the widely used βγ inhibitor GRK2ct (GRK2ct-KERE) and the FRB/FKBP heterodimerization system. We show that GRK2ct-KERE cannot inhibit βγ function when expressed in cells, but recruitment to a specific membrane location recovers the ability of GRK2ct-KERE to inhibit βγ signaling. PM-recruited GRK2ct-KERE inhibits lysophosphatidic acid-induced phosphorylation of Akt, whereas Golgi-recruited GRK2ct-KERE inhibits cargo transport from the TGN to the PM. Moreover, we show that Golgi-recruited GRK2ct-KERE inhibits model basolaterally targeted but not apically targeted cargo delivery, for both PM-destined and secretory cargo, providing the first evidence of selectivity in terms of cargo transport regulated by βγ. Last, we show that Golgi fragmentation induced by ilimaquinone and nocodazole is blocked by βγ inhibition, demonstrating that βγ is a key regulator of multiple pathways that impact Golgi morphology. Thus, we have developed a new molecular tool, recruitable GRK2ct-KERE, to modulate βγ signaling at specific subcellular locations, and we demonstrate novel cargo selectivity for βγ regulation of TGN to PM transport and a novel role for βγ in mediating Golgi fragmentation. PMID:27994056

Inducible Inhibition of Gβγ Reveals Localization-dependent Functions at the Plasma Membrane and Golgi.

Science.gov (United States)

Klayman, Lauren M; Wedegaertner, Philip B

2017-02-03

Heterotrimeric G proteins signal at a variety of endomembrane locations, in addition to their canonical function at the cytoplasmic surface of the plasma membrane (PM), where they are activated by cell surface G protein-coupled receptors. Here we focus on βγ signaling at the Golgi, where βγ activates a signaling cascade, ultimately resulting in vesicle fission from the trans-Golgi network (TGN). To develop a novel molecular tool for inhibiting endogenous βγ in a spatial-temporal manner, we take advantage of a lipid association mutant of the widely used βγ inhibitor GRK2ct (GRK2ct-KERE) and the FRB/FKBP heterodimerization system. We show that GRK2ct-KERE cannot inhibit βγ function when expressed in cells, but recruitment to a specific membrane location recovers the ability of GRK2ct-KERE to inhibit βγ signaling. PM-recruited GRK2ct-KERE inhibits lysophosphatidic acid-induced phosphorylation of Akt, whereas Golgi-recruited GRK2ct-KERE inhibits cargo transport from the TGN to the PM. Moreover, we show that Golgi-recruited GRK2ct-KERE inhibits model basolaterally targeted but not apically targeted cargo delivery, for both PM-destined and secretory cargo, providing the first evidence of selectivity in terms of cargo transport regulated by βγ. Last, we show that Golgi fragmentation induced by ilimaquinone and nocodazole is blocked by βγ inhibition, demonstrating that βγ is a key regulator of multiple pathways that impact Golgi morphology. Thus, we have developed a new molecular tool, recruitable GRK2ct-KERE, to modulate βγ signaling at specific subcellular locations, and we demonstrate novel cargo selectivity for βγ regulation of TGN to PM transport and a novel role for βγ in mediating Golgi fragmentation. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

The Arabidopsis Golgi-localized GDP-L-fucose transporter is required for plant development

DEFF Research Database (Denmark)

Rautengarten, Carsten; Ebert, Berit; Liu, Lifeng

2016-01-01

assays, we show that GFT preferentially transports GDP-L-fucose over other nucleotide sugars in vitro, while GFT1-silenced plants are almost devoid of L-fucose in cell wall-derived xyloglucan and rhamnogalacturonan II. Furthermore, these lines display reduced L-fucose content in N-glycan structures......Nucleotide sugar transport across Golgi membranes is essential for the luminal biosynthesis of glycan structures. Here we identify GDP-fucose transporter 1 (GFT1), an Arabidopsis nucleotide sugar transporter that translocates GDP-L-fucose into the Golgi lumen. Using proteo-liposome-based transport...... accompanied by severe developmental growth defects. We conclude that GFT1 is the major nucleotide sugar transporter for import of GDP-L-fucose into the Golgi and is required for proper plant growth and development....

The Arabidopsis Golgi-localized GDP-L-fucose transporter is required for plant development.

Science.gov (United States)

Rautengarten, Carsten; Ebert, Berit; Liu, Lifeng; Stonebloom, Solomon; Smith-Moritz, Andreia M; Pauly, Markus; Orellana, Ariel; Scheller, Henrik Vibe; Heazlewood, Joshua L

2016-07-06

Nucleotide sugar transport across Golgi membranes is essential for the luminal biosynthesis of glycan structures. Here we identify GDP-fucose transporter 1 (GFT1), an Arabidopsis nucleotide sugar transporter that translocates GDP-L-fucose into the Golgi lumen. Using proteo-liposome-based transport assays, we show that GFT preferentially transports GDP-L-fucose over other nucleotide sugars in vitro, while GFT1-silenced plants are almost devoid of L-fucose in cell wall-derived xyloglucan and rhamnogalacturonan II. Furthermore, these lines display reduced L-fucose content in N-glycan structures accompanied by severe developmental growth defects. We conclude that GFT1 is the major nucleotide sugar transporter for import of GDP-L-fucose into the Golgi and is required for proper plant growth and development.

A novel, modernized Golgi-Cox stain optimized for CLARITY cleared tissue.

Science.gov (United States)

Kassem, Mustafa S; Fok, Sandra Y Y; Smith, Kristie L; Kuligowski, Michael; Balleine, Bernard W

2018-01-15

High resolution neuronal information is extraordinarily useful in understanding the brain's functionality. The development of the Golgi-Cox stain allowed observation of the neuron in its entirety with unrivalled detail. Tissue clearing techniques, e.g., CLARITY and CUBIC, provide the potential to observe entire neuronal circuits intact within tissue and without previous restrictions with regard to section thickness. Here we describe an improved Golgi-Cox stain method, optimised for use with CLARITY and CUBIC that can be used in both fresh and fixed tissue. Using this method, we were able to observe neurons in their entirety within a fraction of the time traditionally taken to clear tissue (48h). We were also able to show for the first-time that Golgi stained tissue is fluorescent when visualized using a multi-photon microscope, allowing us to image synaptic spines with a detail previously unachievable. These novel methods provide cheap and easy to use techniques to investigate the morphology of cellular processes in the brain at a new-found depth, speed, utility and detail, without previous restrictions of time, tissue type and section thickness. This is the first application of a Golgi-Cox stain to cleared brain tissue, it is investigated and discussed in detail, describing different methodologies that may be used, a comparison between the different clearing techniques and lastly the novel interaction of these techniques with this ultra-rapid stain. Copyright © 2017 Elsevier B.V. All rights reserved.

Restoration of compact Golgi morphology in advanced prostate cancer enhances susceptibility to galectin-1-induced apoptosis by modifying mucin O-glycan synthesis.

Science.gov (United States)

Petrosyan, Armen; Holzapfel, Melissa S; Muirhead, David E; Cheng, Pi-Wan

2014-12-01

Prostate cancer progression is associated with upregulation of sialyl-T antigen produced by β-galactoside α-2,3-sialyltransferase-1 (ST3Gal1) but not with core 2-associated polylactosamine despite expression of core 2 N-acetylglucosaminyltransferase-L (C2GnT-L/GCNT1). This property allows androgen-refractory prostate cancer cells to evade galectin-1 (LGALS1)-induced apoptosis, but the mechanism is not known. We have recently reported that Golgi targeting of glycosyltransferases is mediated by golgins: giantin (GOLGB1) for C2GnT-M (GCNT3) and GM130 (GOLGA2)-GRASP65 (GORASP1) or GM130-giantin for core 1 synthase. Here, we show that for Golgi targeting, C2GnT-L also uses giantin exclusively whereas ST3Gal1 uses either giantin or GM130-GRASP65. In addition, the compact Golgi morphology is detected in both androgen-sensitive prostate cancer and normal prostate cells, but fragmented Golgi and mislocalization of C2GnT-L are found in androgen-refractory cells as well as primary prostate tumors (Gleason grade 2-4). Furthermore, failure of giantin monomers to be phosphorylated and dimerized prevents Golgi from forming compact morphology and C2GnT-L from targeting the Golgi. On the other hand, ST3Gal1 reaches the Golgi by an alternate site, GM130-GRASP65. Interestingly, inhibition or knockdown of non-muscle myosin IIA (MYH9) motor protein frees up Rab6a GTPase to promote phosphorylation of giantin by polo-like kinase 3 (PLK3), which is followed by dimerization of giantin assisted by protein disulfide isomerase A3 (PDIA3), and restoration of compact Golgi morphology and targeting of C2GnT-L. Finally, the Golgi relocation of C2GnT-L in androgen-refractory cells results in their increased susceptibility to galectin-1-induced apoptosis by replacing sialyl-T antigen with polylactosamine. This study demonstrates the importance of Golgi morphology and regulation of glycosylation and provides insight into how the Golgi influences cancer progression and metastasis. ©2014 American

Transport According to GARP: Receiving Retrograde Cargo at the Trans-Golgi Network

Science.gov (United States)

Bonifacino, Juan S.; Hierro, Aitor

2010-01-01

Tethering factors are large protein complexes that capture transport vesicles and enable their fusion with acceptor organelles at different stages of the endomembrane system. Recent studies have shed new light on the structure and function of a heterotetrameric tethering factor named Golgi-associated retrograde protein (GARP), which promotes fusion of endosome-derived, retrograde transport carriers to the trans-Golgi network (TGN). X-ray crystallography of the Vps53 and Vps54 subunits of GARP has revealed that this complex is structurally related to other tethering factors such as the exocyst, COG and Dsl1, indicating that they all might work by a similar mechanism. Loss of GARP function compromises the growth, fertility and/or viability of the defective organisms, underscoring the essential nature of GARP-mediated retrograde transport. PMID:21183348

The critical role of Golgi cells in regulating spatio-temporal integration and plasticity at the cerebellum input stage

Directory of Open Access Journals (Sweden)

2008-07-01

Full Text Available After the discovery at the end of the 19th century (Golgi, 1883, the Golgi cell was precisely described by S.R. y Cajal (see Cajal, 1987, 1995 and functionally identified as an inhibitory interneuron 50 years later by J.C. Eccles and colleagues (Eccles e al., 1967. Then, its role has been casted by Marr (1969 within the Motor Learning Theory as a codon size regulator of granule cell activity. It was immediately clear that Golgi cells had to play a critical role, since they are the main inhibitory interneuron of the granular layer and control activity of as many as 100 millions granule cells. In vitro, Golgi cells show pacemaking, resonance, phase-reset and rebound-excitation in the theta-frequency band. These properties are likely to impact on their activity in vivo, which shows irregular spontaneous beating modulated by sensory inputs and burst responses to punctuate stimulation followed by a silent pause. Moreover, investigations have given insight into Golgi cells connectivity within the cerebellar network and on their impact on the spatio-temporal organization of activity. It turns out that Golgi cells can control both the temporal dynamics and the spatial distribution of information transmitted through the cerebellar network. Moreover, Golgi cells regulate the induction of long-term synaptic plasticity at the mossy fiber - granule cell synapse. Thus, the concept is emerging that Golgi cells are of critical importance for regulating granular layer network activity bearing important consequences for cerebellar computation as a whole.

Acyl-CoA-binding protein (ACBP) localizes to the endoplasmic reticulum and Golgi in a ligand-dependent manner in mammalian cells

DEFF Research Database (Denmark)

Hansen, Jesper S; Færgeman, Nils J; Kragelund, Birthe B

2008-01-01

showed that ACBP targeted to the ER (endoplasmic reticulum) and Golgi in a ligand-binding-dependent manner. A variant Y28F/K32A-FACI-50, which is unable to bind acyl-CoA, did no longer show association with the ER and became segregated from the Golgi, as analysed by intensity correlation calculations....... Depletion of fatty acids from cells by addition of FAFBSA (fatty-acid-free BSA) significantly decreased FACI-50 association with the Golgi, whereas fatty acid overloading increased Golgi association, strongly supporting that ACBP associates with the Golgi in a ligand-dependent manner. FRAP (fluorescence...... recovery after photobleaching) showed that the fatty-acid-induced targeting of FACI-50 to the Golgi resulted in a 5-fold reduction in FACI-50 mobility. We suggest that ACBP is targeted to the ER and Golgi in a ligand-binding-dependent manner in living cells and propose that ACBP may be involved...

Direct interaction of the Golgi V-ATPase a-subunit isoform with PI(4)P drives localization of Golgi V-ATPases in yeast.

Science.gov (United States)

Banerjee, Subhrajit; Kane, Patricia M

2017-09-15

Luminal pH and phosphoinositide content are fundamental features of organelle identity. Vacuolar H + -ATPases (V-ATPases) drive organelle acidification in all eukaryotes, and membrane-bound a-subunit isoforms of the V-ATPase are implicated in organelle-specific targeting and regulation. Earlier work demonstrated that the endolysosomal lipid PI(3,5)P 2 activates V-ATPases containing the vacuolar a-subunit isoform in Saccharomyces cerevisiae Here we demonstrate that PI(4)P, the predominant Golgi phosphatidylinositol (PI) species, directly interacts with the cytosolic amino terminal (NT) domain of the yeast Golgi V-ATPase a-isoform Stv1. Lysine-84 of Stv1NT is essential for interaction with PI(4)P in vitro and in vivo, and interaction with PI(4)P is required for efficient localization of Stv1-containing V-ATPases. The cytosolic NT domain of the human V-ATPase a2 isoform specifically interacts with PI(4)P in vitro, consistent with its Golgi localization and function. We propose that NT domains of V o a-subunit isoforms interact specifically with PI lipids in their organelles of residence. These interactions can transmit organelle-specific targeting or regulation information to V-ATPases. © 2017 Banerjee and Kane. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Somal and dendritic development of human CA3 pyramidal neurons from midgestation to middle childhood: a quantitative Golgi study.

Science.gov (United States)

Lu, Dahua; He, Lixin; Xiang, Wei; Ai, Wei-Min; Cao, Ye; Wang, Xiao-Sheng; Pan, Aihua; Luo, Xue-Gang; Li, Zhiyuan; Yan, Xiao-Xin

2013-01-01

The CA3 area serves a key relay on the tri-synaptic loop of the hippocampal formation which supports multiple forms of mnemonic processing, especially spatial learning and memory. To date, morphometric data about human CA3 pyramidal neurons are relatively rare, with little information available for their pre- and postnatal development. Herein, we report a set of developmental trajectory data, including somal growth, dendritic elongation and branching, and spine formation, of human CA3 pyramidal neurons from midgestation stage to middle childhood. Golgi-impregnated CA3 pyramidal neurons in fetuses at 19, 20, 26, 35, and 38 weeks of gestation (GW) and a child at 8 years of age (Y) were analyzed by Neurolucida morphometry. Somal size of the impregnated CA3 cells increased age-dependently among the cases. The length of the apical and basal dendrites of these neurons increased between 26 GW to 38 GW, and appeared to remain stable afterward until 8 Y. Dendritic branching points increased from 26 GW to 38 GW, with that on the apical dendrites slightly reduced at 8 Y. Spine density on the apical and basal dendrites increased progressively from 26 GW to 8 Y. These data suggest that somal growth and dendritic arborization of human CA3 pyramidal neurons occur largely during the second to third trimester. Spine development and likely synaptogenesis on CA3 pyramidal cells progress during the third prenatal trimester and may continue throughout childhood. Copyright © 2012 Wiley Periodicals, Inc.

Structural Insights into Arl1-Mediated Targeting of the Arf-GEF BIG1 to the trans-Golgi

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Antonio Galindo

2016-07-01

Full Text Available The GTPase Arf1 is the major regulator of vesicle traffic at both the cis- and trans-Golgi. Arf1 is activated at the cis-Golgi by the guanine nucleotide exchange factor (GEF GBF1 and at the trans-Golgi by the related GEF BIG1 or its paralog, BIG2. The trans-Golgi-specific targeting of BIG1 and BIG2 depends on the Arf-like GTPase Arl1. We find that Arl1 binds to the dimerization and cyclophilin binding (DCB domain in BIG1 and report a crystal structure of human Arl1 bound to this domain. Residues in the DCB domain that bind Arl1 are required for BIG1 to locate to the Golgi in vivo. DCB domain-binding residues in Arl1 have a distinct conformation from those in known Arl1-effector complexes, and this plasticity allows Arl1 to interact with different effectors of unrelated structure. The findings provide structural insight into how Arf1 GEFs, and hence active Arf1, achieve their correct subcellular distribution.

The Prenylated Rab GTPase Receptor PRA1.F4 Contributes to Protein Exit from the Golgi Apparatus.

Science.gov (United States)

Lee, Myoung Hui; Yoo, Yun-Joo; Kim, Dae Heon; Hanh, Nguyen Hong; Kwon, Yun; Hwang, Inhwan

2017-07-01

Prenylated Rab acceptor1 (PRA1) functions in the recruitment of prenylated Rab proteins to their cognate organelles. Arabidopsis ( Arabidopsis thaliana ) contains a large number of proteins belonging to the AtPRA1 family. However, their physiological roles remain largely unknown. Here, we investigated the physiological role of AtPRA1.F4, a member of the AtPRA1 family. A T-DNA insertion knockdown mutant of AtPRA1.F4 , atpra1.f4 , was smaller in stature than parent plants and possessed shorter roots, whereas transgenic plants overexpressing HA:AtPRA1.F4 showed enhanced development of secondary roots and root hairs. However, both overexpression and knockdown plants exhibited increased sensitivity to high-salt stress, lower vacuolar Na + /K + -ATPase and plasma membrane ATPase activities, lower and higher pH in the vacuole and apoplast, respectively, and highly vesiculated Golgi apparatus. HA:AtPRA1.F4 localized to the Golgi apparatus and assembled into high-molecular-weight complexes. atpra1.f4 plants displayed a defect in vacuolar trafficking, which was complemented by low but not high levels of HA : AtPRA1.F4 Overexpression of HA:AtPRA1.F4 also inhibited protein trafficking at the Golgi apparatus, albeit differentially depending on the final destination or type of protein: trafficking of vacuolar proteins, plasma membrane proteins, and trans-Golgi network (TGN)-localized SYP61 was strongly inhibited; trafficking of TGN-localized SYP51 was slightly inhibited; and trafficking of secretory proteins and TGN-localized SYP41 was negligibly or not significantly inhibited. Based on these results, we propose that Golgi-localized AtPRA1.F4 is involved in the exit of many but not all types of post-Golgi proteins from the Golgi apparatus. Additionally, an appropriate level of AtPRA1.F4 is crucial for its function at the Golgi apparatus. © 2017 American Society of Plant Biologists. All Rights Reserved.

A model for the self-organization of vesicular flux and protein distributions in the Golgi apparatus.

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Iaroslav Ispolatov

Full Text Available The generation of two non-identical membrane compartments via exchange of vesicles is considered to require two types of vesicles specified by distinct cytosolic coats that selectively recruit cargo, and two membrane-bound SNARE pairs that specify fusion and differ in their affinities for each type of vesicles. The mammalian Golgi complex is composed of 6-8 non-identical cisternae that undergo gradual maturation and replacement yet features only two SNARE pairs. We present a model that explains how distinct composition of Golgi cisternae can be generated with two and even a single SNARE pair and one vesicle coat. A decay of active SNARE concentration in aging cisternae provides the seed for a cis[Formula: see text]trans SNARE gradient that generates the predominantly retrograde vesicle flux which further enhances the gradient. This flux in turn yields the observed inhomogeneous steady-state distribution of Golgi enzymes, which compete with each other and with the SNAREs for incorporation into transport vesicles. We show analytically that the steady state SNARE concentration decays exponentially with the cisterna number. Numerical solutions of rate equations reproduce the experimentally observed SNARE gradients, overlapping enzyme peaks in cis, medial and trans and the reported change in vesicle nature across the Golgi: Vesicles originating from younger cisternae mostly contain Golgi enzymes and SNAREs enriched in these cisternae and extensively recycle through the Endoplasmic Reticulum (ER, while the other subpopulation of vesicles contains Golgi proteins prevalent in older cisternae and hardly reaches the ER.

Human Diseases Associated with Form and Function of the Golgi Complex

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Jeremy C. Simpson

2013-09-01

Full Text Available The Golgi complex lies at the heart of the secretory pathway and is responsible for modifying proteins and lipids, as well as sorting newly synthesized molecules to their correct destination. As a consequence of these important roles, any changes in its proteome can negatively affect its function and in turn lead to disease. Recently, a number of proteins have been identified, which when either depleted or mutated, result in diseases that affect various organ systems. Here we describe how these proteins have been linked to the Golgi complex, and specifically how they affect either the morphology, membrane traffic or glycosylation ability of this organelle.

Sphingomyelin synthesis in rat liver occurs predominantly at the cis and medial cisternae of the Golgi apparatus

International Nuclear Information System (INIS)

Futerman, A.H.; Stieger, B.; Hubbard, A.L.; Pagano, R.E.

1990-01-01

The intracellular site of sphingomyelin (SM) synthesis was examined in subcellular fractions from rat liver using a radioactive ceramide analog N-([1-14C]hexanoyl)-D-erythro-sphingosine. This lipid readily transferred from a complex with bovine serum albumin to liver fractions without disrupting the membranes, and was metabolized to radioactive SM. To prevent degradation of the newly synthesized SM to ceramide, all experiments were performed in the presence of EDTA to minimize neutral sphingomyelinase activity and at neutral pH to minimize acid sphingomyelinase activity. An intact Golgi apparatus fraction gave an 85-98-fold enrichment of SM synthesis and a 58-83-fold enrichment of galactosyltransferase activity. Controlled trypsin digestion demonstrated that SM synthesis was localized to the lumen of intact Golgi apparatus vesicles. Although small amounts of SM synthesis were detected in plasma membrane and rough microsome fractions, after accounting for contamination by Golgi apparatus membranes, their combined activity contributed less than 13% of the total SM synthesis in rat liver. Subfractions of the Golgi apparatus were obtained and characterized by immunoblotting and biochemical assays using cis/medial (mannosidase II) and trans (sialyltransferase and galactosyltransferase) Golgi apparatus markers. The specific activity of SM synthesis was highest in enriched cis and medial fractions but far lower in a trans fraction. We conclude that SM synthesis in rat liver occurs predominantly in the cis and medial cisternae of the Golgi apparatus and not at the plasma membrane or endoplasmic reticulum as has been previously suggested

Monocrotaline pyrrole-induced megalocytosis of lung and breast epithelial cells: Disruption of plasma membrane and Golgi dynamics and an enhanced unfolded protein response

International Nuclear Information System (INIS)

Mukhopadhyay, Somshuvra; Shah, Mehul; Patel, Kirit; Sehgal, Pravin B.

2006-01-01

The pyrrolizidine alkaloid monocrotaline (MCT) initiates pulmonary hypertension by inducing a 'megalocytosis' phenotype in target pulmonary arterial endothelial, smooth muscle and Type II alveolar epithelial cells. In cultured endothelial cells, a single exposure to the pyrrolic derivative of monocrotaline (MCTP) results in large cells with enlarged endoplasmic reticulum (ER) and Golgi and increased vacuoles. However, these cells fail to enter mitosis. Largely based upon data from endothelial cells, we proposed earlier that a disruption of the trafficking and mitosis-sensor functions of the Golgi (the 'Golgi blockade' hypothesis) may represent the subcellular mechanism leading to MCTP-induced megalocytosis. In the present study, we investigated the applicability of the Golgi blockade hypothesis to epithelial cells. MCTP induced marked megalocytosis in cultures of lung A549 and breast MCF-7 cells. This was associated with a change in the distribution of the cis-Golgi scaffolding protein GM130 from a discrete juxtanuclear localization to a circumnuclear distribution consistent with an anterograde block of GM130 trafficking to/through the Golgi. There was also a loss of plasma membrane caveolin-1 and E-cadherin, cortical actin together with a circumnuclear accumulation of clathrin heavy chain (CHC) and α-tubulin. Flotation analyses revealed losses/alterations in the association of caveolin-1, E-cadherin and CHC with raft microdomains. Moreover, megalocytosis was accompanied by an enhanced unfolded protein response (UPR) as evidenced by nuclear translocation of Ire1α and glucose regulated protein 58 (GRP58/ER-60/ERp57) and a circumnuclear accumulation of PERK kinase and protein disulfide isomerase (PDI). These data further support the hypothesis that an MCTP-induced Golgi blockade and enhanced UPR may represent the subcellular mechanism leading to enlargement of ER and Golgi and subsequent megalocytosis

Golgi bypass: skirting around the heart of classical secretion

NARCIS (Netherlands)

Grieve, A.; Rabouille, C.

2011-01-01

Classical secretion consists of the delivery of transmembrane and soluble proteins to the plasma membrane and the extracellular medium, respectively, and is mediated by the organelles of the secretory pathway, the Endoplasmic Reticulum (ER), the ER exit sites, and the Golgi, as described by the

Golgi-associated Rab14, a new regulator for Chlamydia trachomatis infection outcome.

Science.gov (United States)

Capmany, Anahí; Leiva, Natalia; Damiani, María Teresa

2011-09-01

Chlamydia trachomatis is the causing agent of the most frequent bacterial sexually-transmitted diseases worldwide and is an underlying cause of chronic pelvic inflammatory diseases and cervical cancer. It is an obligate intracellular bacterium that establishes a close relationship with the Golgi complex and parasites the biosynthetic machinery of host cells. In a recent study, we have demonstrated that Rab14, a newly-described Golgi-associated Rab, is involved in the delivery of sphingolipids to the growing bacteria-containing vacuole. The interference with Rab14-controlled trafficking pathways delays chlamydial inclusion enlargement, decreases bacterial lipid uptake, negatively impact on bacterial differentiation, and reduces bacterial progeny and infectivity. C. trachomatis manipulation of host trafficking pathways for the acquisition of endogenously-biosynthesized nutrients arises as one of the characteristics of this highly evolved pathogen. The development of therapeutic strategies targeted to interfere with bacterium-host cell interaction is a new challenge for pharmacological approaches to control chlamydial infections.

TCR¿ is transported to and retained in the Golgi apparatus independently of other TCR chains: implications for TCR assembly

DEFF Research Database (Denmark)

Dietrich, J; Kastrup, J; Lauritsen, Jens Peter Holst

1999-01-01

. This study focused on the intracellular localization and transport of partially assembled TCR complexes as determined by confocal microscopy analyses. We found that none of the TCR chains except for TCRzeta were allowed to exit the ER in T cell variants in which the hexameric CD3gammaepsilonTi alphabetaCD3...... deltaepsilon complex was not formed. Interestingly, TCRzeta was exported from the ER independently of other TCR chains and was predominantly located in a compartment identified as the Golgi apparatus. Furthermore, in the TCRzeta-negative cell line MA5.8, the hexameric CD3gammaepsilonTi alphabetaCD3...... the ER to the Golgi apparatus independently of each other and that these partial TCR complexes are unable to be efficiently expressed at the cell surface suggest that final TCR assembly occurs in the Golgi apparatus....

A catechol oxidase AcPPO from cherimoya (Annona cherimola Mill.) is localized to the Golgi apparatus.

Science.gov (United States)

Olmedo, Patricio; Moreno, Adrián A; Sanhueza, Dayan; Balic, Iván; Silva-Sanzana, Christian; Zepeda, Baltasar; Verdonk, Julian C; Arriagada, César; Meneses, Claudio; Campos-Vargas, Reinaldo

2018-01-01

Cherimoya (Annona cherimola) is an exotic fruit with attractive organoleptic characteristics. However, it is highly perishable and susceptible to postharvest browning. In fresh fruit, browning is primarily caused by the polyphenol oxidase (PPO) enzyme catalyzing the oxidation of o-diphenols to quinones, which polymerize to form brown melanin pigment. There is no consensus in the literature regarding a specific role of PPO, and its subcellular localization in different plant species is mainly described within plastids. The present work determined the subcellular localization of a PPO protein from cherimoya (AcPPO). The obtained results revealed that the AcPPO- green fluorescent protein co-localized with a Golgi apparatus marker, and AcPPO activity was present in Golgi apparatus-enriched fractions. Likewise, transient expression assays revealed that AcPPO remained active in Golgi apparatus-enriched fractions obtained from tobacco leaves. These results suggest a putative function of AcPPO in the Golgi apparatus of cherimoya, providing new perspectives on PPO functionality in the secretory pathway, its effects on cherimoya physiology, and the evolution of this enzyme. Copyright © 2017. Published by Elsevier B.V.

Phospholipase D is involved in the formation of Golgi associated clathrin coated vesicles in human parotid duct cells.

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Lorena Brito de Souza

Full Text Available Phospholipase D (PLD has been implicated in many cellular functions, such as vesicle trafficking, exocytosis, differentiation, and proliferation. The aim of this study was to characterize the role of PLD in HSY cells, a human cell line originating from the intercalated duct of the parotid gland. As the function and intracellular localization of PLD varies according to cell type, initially, the intracellular localization of PLD1 and PLD2 was determined. By immunofluorescence, PLD1 and PLD2 both showed a punctate cytoplasmic distribution with extensive co-localization with TGN-46. PLD1 was also found in the nucleus, while PLD2 was associated with the plasma membrane. Treatment of cells with the primary alcohol 1-butanol inhibits the hydrolysis of phosphatidylcoline by PLD thereby suppressing phosphatidic acid (PA production. In untreated HSY cells, there was only a slight co-localization of PLD with the clathrin coated vesicles. When HSY cells were incubated with 1-butanol the total number of clathrin coated vesicles increased, especially in the juxtanuclear region and the co-localization of PLD with the clathrin coated vesicles was augmented. Transmission electron microscopy confirmed that the number of Golgi-associated coated vesicles was greater. Treatment with 1-butanol also affected the Golgi apparatus, increasing the volume of the Golgi saccules. The decrease in PA levels after treatment with 1-butanol likewise resulted in an accumulation of enlarged lysosomes in the perinuclear region. Therefore, in HSY cells PLD appears to be involved in the formation of Golgi associated clathrin coated vesicles as well as in the structural maintenance of the Golgi apparatus.

OSBP-related protein 11 (ORP11) dimerizes with ORP9 and localizes at the Golgi-late endosome interface

International Nuclear Information System (INIS)

Zhou, You; Li, Shiqian; Maeyraenpaeae, Mikko I.; Zhong, Wenbin; Baeck, Nils; Yan, Daoguang; Olkkonen, Vesa M.

2010-01-01

We characterize here ORP11, a member of the oxysterol-binding protein family. ORP11 is present at highest levels in human ovary, testis, kidney, liver, stomach, brain, and adipose tissue. Immunohistochemistry demonstrates abundant ORP11 in the epithelial cells of kidney tubules, testicular tubules, caecum, and skin. ORP11 in HEK293 cells resides on Golgi complex and LE, co-localizing with GFP-Rab9, TGN46, GFP-Rab7, and a fluorescent medial-trans-Golgi marker. Under electron microscopic observation, cells overexpressing ORP11 displayed lamellar lipid bodies associated with vacuolar structures or the Golgi complex, indicating a disturbance of lipid trafficking. N-terminal fragment of ORP11 (aa 1-292) localized partially to Golgi, but displayed enhanced localization on Rab7- and Rab9-positive LE, while the C-terminal ligand-binding domain (aa 273-747) was cytosolic, demonstrating that the membrane targeting determinants are N-terminal. Yeast two-hybrid screen revealed interaction of ORP11 with the related ORP9. The interacting region was delineated within aa 98-372 of ORP9 and aa 154-292 of ORP11. Overexpressed ORP9 was able to recruit EGFP-ORP11 to membranes, and ORP9 silencing inhibited ORP11 Golgi association. The results identify ORP11 as an OSBP homologue distributing at the Golgi-LE interface and define the ORP9-ORP11 dimer as a functional unit that may act as an intracellular lipid sensor or transporter.

OSBP-related protein 11 (ORP11) dimerizes with ORP9 and localizes at the Golgi-late endosome interface

Energy Technology Data Exchange (ETDEWEB)

Zhou, You [Minerva Foundation Institute for Medical Research, Biomedicum 2U, and National Institute for Health and Welfare/Public Health Genomics Unit, Biomedicum 1, FI-00290, Helsinki (Finland); Li, Shiqian [Department of Biology, Jinan University, Guangzhou 510632 (China); Maeyraenpaeae, Mikko I. [Wihuri Research Institute, FI-00140 Helsinki, and the Department of Forensic Medicine, FI-00014 University of Helsinki (Finland); Zhong, Wenbin [Department of Biology, Jinan University, Guangzhou 510632 (China); Baeck, Nils [Institute of Biomedicine/Anatomy, FI-00014 University of Helsinki, Helsinki (Finland); Yan, Daoguang [Department of Biology, Jinan University, Guangzhou 510632 (China); Olkkonen, Vesa M., E-mail: vesa.olkkonen@helsinki.fi [Minerva Foundation Institute for Medical Research, Biomedicum 2U, and National Institute for Health and Welfare/Public Health Genomics Unit, Biomedicum 1, FI-00290, Helsinki (Finland); Institute of Biomedicine/Anatomy, FI-00014 University of Helsinki, Helsinki (Finland)

2010-11-15

We characterize here ORP11, a member of the oxysterol-binding protein family. ORP11 is present at highest levels in human ovary, testis, kidney, liver, stomach, brain, and adipose tissue. Immunohistochemistry demonstrates abundant ORP11 in the epithelial cells of kidney tubules, testicular tubules, caecum, and skin. ORP11 in HEK293 cells resides on Golgi complex and LE, co-localizing with GFP-Rab9, TGN46, GFP-Rab7, and a fluorescent medial-trans-Golgi marker. Under electron microscopic observation, cells overexpressing ORP11 displayed lamellar lipid bodies associated with vacuolar structures or the Golgi complex, indicating a disturbance of lipid trafficking. N-terminal fragment of ORP11 (aa 1-292) localized partially to Golgi, but displayed enhanced localization on Rab7- and Rab9-positive LE, while the C-terminal ligand-binding domain (aa 273-747) was cytosolic, demonstrating that the membrane targeting determinants are N-terminal. Yeast two-hybrid screen revealed interaction of ORP11 with the related ORP9. The interacting region was delineated within aa 98-372 of ORP9 and aa 154-292 of ORP11. Overexpressed ORP9 was able to recruit EGFP-ORP11 to membranes, and ORP9 silencing inhibited ORP11 Golgi association. The results identify ORP11 as an OSBP homologue distributing at the Golgi-LE interface and define the ORP9-ORP11 dimer as a functional unit that may act as an intracellular lipid sensor or transporter.

Characterization of the sterol and phosphatidylinositol 4-phosphate binding properties of Golgi-associated OSBP-related protein 9 (ORP9.

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Xinwei Liu

Full Text Available Oxysterol binding protein (OSBP and OSBP-related proteins (ORPS have a conserved lipid-binding fold that accommodates cholesterol, oxysterols and/or phospholipids. The diversity of OSBP/ORPs and their potential ligands has complicated the analysis of transfer and signalling properties of this mammalian gene family. In this study we explored the use of the fluorescent sterol cholestatrienol (CTL to measure sterol binding by ORP9 and competition by other putative ligands. Relative to cholesterol, CTL and dehydroergosterol (DHE were poor ligands for OSBP. In contrast, both long (ORP9L and short (ORP9S variants of ORP9 rapidly extracted CTL, and to a lesser extent DHE, from liposomes. ORP9L and ORP9S also extracted [32P]phosphatidylinositol 4-phosphate (PI-4P from liposomes, which was inhibited by mutating two conserved histidine residues (HH488,489AA at the entrance to the binding pocket but not by a mutation in the lid region that inhibited cholesterol binding. Results of direct binding and competition assays showed that phosphatidylserine was poorly extracted from liposomes by ORP9 compared to CTL and PI-4P. ORP9L and PI-4P did not co-localize in the trans-Golgi/TGN of HeLa cells, and siRNA silencing of ORP9L expression did not affect PI-4P distribution in the Golgi apparatus. However, transient overexpression of ORP9L or ORP9S in CHO cells, but not the corresponding PI-4P binding mutants, prevented immunostaining of Golgi-associated PI-4P. The apparent sequestration of Golgi PI-4P by ORP9S was identified as a possible mechanism for its growth inhibitory effects. These studies identify ORP9 as a dual sterol/PI-4P binding protein that could regulate PI-4P in the Golgi apparatus.

Characterization of the sterol and phosphatidylinositol 4-phosphate binding properties of Golgi-associated OSBP-related protein 9 (ORP9).

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Liu, Xinwei; Ridgway, Neale D

2014-01-01

Oxysterol binding protein (OSBP) and OSBP-related proteins (ORPS) have a conserved lipid-binding fold that accommodates cholesterol, oxysterols and/or phospholipids. The diversity of OSBP/ORPs and their potential ligands has complicated the analysis of transfer and signalling properties of this mammalian gene family. In this study we explored the use of the fluorescent sterol cholestatrienol (CTL) to measure sterol binding by ORP9 and competition by other putative ligands. Relative to cholesterol, CTL and dehydroergosterol (DHE) were poor ligands for OSBP. In contrast, both long (ORP9L) and short (ORP9S) variants of ORP9 rapidly extracted CTL, and to a lesser extent DHE, from liposomes. ORP9L and ORP9S also extracted [32P]phosphatidylinositol 4-phosphate (PI-4P) from liposomes, which was inhibited by mutating two conserved histidine residues (HH488,489AA) at the entrance to the binding pocket but not by a mutation in the lid region that inhibited cholesterol binding. Results of direct binding and competition assays showed that phosphatidylserine was poorly extracted from liposomes by ORP9 compared to CTL and PI-4P. ORP9L and PI-4P did not co-localize in the trans-Golgi/TGN of HeLa cells, and siRNA silencing of ORP9L expression did not affect PI-4P distribution in the Golgi apparatus. However, transient overexpression of ORP9L or ORP9S in CHO cells, but not the corresponding PI-4P binding mutants, prevented immunostaining of Golgi-associated PI-4P. The apparent sequestration of Golgi PI-4P by ORP9S was identified as a possible mechanism for its growth inhibitory effects. These studies identify ORP9 as a dual sterol/PI-4P binding protein that could regulate PI-4P in the Golgi apparatus.

Xyloglucan biosynthesis by Golgi membranes from suspension-cultured sycamore (Acer pseudoplatanus) cells

International Nuclear Information System (INIS)

White, A.R.; Xin, Yi

1990-01-01

Xyloglucan is a major hemicellulose polysaccharide in plant cell walls. Biosynthesis of such cell wall polysaccharides is closely linked to the process of plant cell growth and development. Xyloglucan polysaccharides consist of a β-1,4 glucan backbone synthesized by xyloglucan synthase and sidechains of xylose, galactose, and fucose added by other transferase enzymes. Most plant Golgi and plasma membranes also contain glucan synthases I ampersand II, which make β-1,4 and β-1,3 glucans, respectively. All of these enzymes have very similar activities. Cell walls on suspension-cultured cells from Acer pseudoplatanus (sycamore maple) were enzymatically softened prior to cell disruption by passing through a 30 μm nylon screen. Cell membranes from homogenates were separated by ultracentrifugation on top-loaded or flotation sucrose density gradients. Samples were collected by gradient fractionation and assayed for membrane markers and xyloglucan and glucan synthase activities. Standard marker assays (cyt. c reductase for eR, IDPase ampersand UDPase for Golgi, and eosin 5'-malelmide binding for plasma membrane) showed partial separation of these three membrane types. Golgi and plasma membrane markers overlapped in most gradients. Incorporation of 14 C-labeled sugars from UDP-glucose and UDP-xylose was used to detect xyloglucan synthase, glucan synthases I ampersand II, and xylosyl transferase in Golgi membrane fractions. These activities overlapped, although distinct peaks of xyloglucan synthase and xylosyl transferase were found. Ca ++ had a stimulatory effect on glucan synthases I ampersand II, while Mn ++ had an inhibitory effect on glucan synthase I in the presence of Ca ++ . The similarity of these various synthase activities demonstrates the need for careful structural characterization of newly synthesized polysaccharides

Retrograde transport of protein toxins through the Golgi apparatus

DEFF Research Database (Denmark)

Sandvig, Kirsten; Skotland, Tore; van Deurs, Bo

2013-01-01

at the cell surface, and they are endocytosed both by clathrin-dependent and clathrin-independent mechanisms. Sorting to the Golgi and retrograde transport to the endoplasmic reticulum (ER) are common to these toxins, but the exact mechanisms turn out to be toxin and cell-type dependent. In the ER...

G-rich, a Drosophila selenoprotein, is a Golgi-resident type III membrane protein

International Nuclear Information System (INIS)

Chen, Chang Lan; Shim, Myoung Sup; Chung, Jiyeol; Yoo, Hyun-Seung; Ha, Ji Min; Kim, Jin Young; Choi, Jinmi; Zang, Shu Liang; Hou, Xiao; Carlson, Bradley A.; Hatfield, Dolph L.; Lee, Byeong Jae

2006-01-01

G-rich is a Drosophila melanogaster selenoprotein, which is a homologue of human and mouse SelK. Subcellular localization analysis using GFP-tagged G-rich showed that G-rich was localized in the Golgi apparatus. The fusion protein was co-localized with the Golgi marker proteins but not with an endoplasmic reticulum (ER) marker protein in Drosophila SL2 cells. Bioinformatic analysis of G-rich suggests that this protein is either type II or type III transmembrane protein. To determine the type of transmembrane protein experimentally, GFP-G-rich in which GFP was tagged at the N-terminus of G-rich, or G-rich-GFP in which GFP was tagged at the C-terminus of G-rich, were expressed in SL2 cells. The tagged proteins were then digested with trypsin, and analyzed by Western blot analysis. The results showed that the C-terminus of the G-rich protein was exposed to the cytoplasm indicating it is a type III microsomal membrane protein. G-rich is First selenoprotein identified in the Golgi apparatus

Overexpression of Rab22a hampers the transport between endosomes and the Golgi apparatus

International Nuclear Information System (INIS)

Mesa, Rosana; Magadan, Javier; Barbieri, Alejandro; Lopez, Cecilia; Stahl, Philip D.; Mayorga, Luis S.

2005-01-01

The transport and sorting of soluble and membrane-associated macromolecules arriving at endosomal compartments require a complex set of Rab proteins. Rab22a has been localized to the endocytic compartment; however, very little is known about the function of Rab22a and inconsistent results have been reported in studies performed in different cell lines. To characterize the function of Rab22a in endocytic transport, the wild-type protein (Rab22a WT), a hydrolysis-deficient mutant (Rab22a Q64L), and a mutant with reduced affinity for GTP (Rab22a S19N) were expressed in CHO cells. None of the three Rab22a constructs affected the transport of rhodamine-dextran to lysosomes, the digestion of internalized proteins, or the lysosomal localization of cathepsin D. In contrast with the mild effect of Rab22a on the endosome-lysosome route, cells expressing Rab22a WT and Rab22a Q64L presented a strong delay in the retrograde transport of cholera toxin from endosomes to the Golgi apparatus. Moreover, these cells accumulated the cation independent mannose 6-phosphate receptor in endosomes. These observations indicate that Rab22a can affect the trafficking from endosomes to the Golgi apparatus probably by promoting fusion among endosomes and impairing the proper segregation of membrane domains required for targeting to the trans-Golgi network (TGN)

In silico analysis of the fucosylation-associated genome of the human blood fluke Schistosoma mansoni: cloning and characterization of the enzymes involved in GDP-L-fucose synthesis and Golgi import.

Science.gov (United States)

Peterson, Nathan A; Anderson, Tavis K; Wu, Xiao-Jun; Yoshino, Timothy P

2013-07-09

Carbohydrate structures of surface-expressed and secreted/excreted glycoconjugates of the human blood fluke Schistosoma mansoni are key determinants that mediate host-parasite interactions in both snail and mammalian hosts. Fucose is a major constituent of these immunologically important glycans, and recent studies have sought to characterize fucosylation-associated enzymes, including the Golgi-localized fucosyltransferases that catalyze the transfer of L-fucose from a GDP-L-fucose donor to an oligosaccharide acceptor. Importantly, GDP-L-fucose is the only nucleotide-sugar donor used by fucosyltransferases and its availability represents a bottleneck in fucosyl-glycotope expression. A homology-based genome-wide bioinformatics approach was used to identify and molecularly characterize the enzymes that contribute to GDP-L-fucose synthesis and Golgi import in S. mansoni. Putative functions were further investigated through molecular phylogenetic and immunocytochemical analyses. We identified homologs of GDP-D-mannose-4,6-dehydratase (GMD) and GDP-4-keto-6-deoxy-D-mannose-3,5-epimerase-4-reductase (GMER), which constitute a de novo pathway for GDP-L-fucose synthesis, in addition to a GDP-L-fucose transporter (GFT) that putatively imports cytosolic GDP-L-fucose into the Golgi. In silico primary sequence analyses identified characteristic Rossman loop and short-chain dehydrogenase/reductase motifs in GMD and GMER as well as 10 transmembrane domains in GFT. All genes are alternatively spliced, generating variants of unknown function. Observed quantitative differences in steady-state transcript levels between miracidia and primary sporocysts may contribute to differential glycotope expression in early larval development. Additionally, analyses of protein expression suggest the occurrence of cytosolic GMD and GMER in the ciliated epidermal plates and tegument of miracidia and primary sporocysts, respectively, which is consistent with previous localization of highly

Golgi apparatus-localized synaptotagmin 2 is required for unconventional secretion in Arabidopsis.

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Haiyan Zhang

Full Text Available BACKGROUND: Most secretory proteins contain signal peptides that direct their sorting to the ER and secreted via the conventional ER/Golgi transport pathway, while some signal-peptide-lacking proteins have been shown to export through ER/Golgi independent secretory pathways. Hygromycin B is an aminoglycoside antibiotic produced by Streptomyces hygroscopicus that is active against both prokaryotic and eukaryotic cells. The hygromycin phosphotransferase (HYG(R can phosphorylate and inactivate the hygromycin B, and has been widely used as a positive selective marker in the construction of transgenic plants. However, the localization and trafficking of HYG(R in plant cells remain unknown. Synaptotagmins (SYTs are involved in controlling vesicle endocytosis and exocytosis as calcium sensors in animal cells, while their functions in plant cells are largely unclear. METHODOLOGY/PRINCIPAL FINDINGS: We found Arabidopsis synaptotagmin SYT2 was localized on the Golgi apparatus by immunofluorescence and immunogold labeling. Surprisingly, co-expression of SYT2 and HYG(R caused hypersensitivity of the transgenic Arabidopsis plants to hygromycin B. HYG(R, which lacks a signal sequence, was present in the cytoplasm as well as in the extracellular space in HYG(R-GFP transgenic Arabidopsis plants and its secretion is not sensitive to brefeldin A treatment, suggesting it is not secreted via the conventional secretory pathway. Furthermore, we found that HYG(R-GFP was truncated at carboxyl terminus of HYG(R shortly after its synthesis, and the cells deficient SYT2 failed to efficiently truncate HYG(R-GFP,resulting in HYG(R-GFP accumulated in prevacuoles/vacuoles, indicating that SYT2 was involved in HYG(R-GFP trafficking and secretion. CONCLUSION/SIGNIFICANCE: These findings reveal for the first time that SYT2 is localized on the Golgi apparatus and regulates HYG(R-GFP secretion via the unconventional protein transport from the cytosol to the extracelluar matrix in

A smart drug: a pH-responsive photothermal ablation agent for Golgi apparatus activated cancer therapy.

Science.gov (United States)

Xue, Fengfeng; Wen, Ying; Wei, Peng; Gao, Yilin; Zhou, Zhiguo; Xiao, Shuzhang; Yi, Tao

2017-06-13

We report a pH-responsive photothermal ablation agent (pH-PTT) based on cyanine dyes for photothermal therapy (PTT). The nanoparticles formed by BSA and pH-PTT preferentially accumulated in the Golgi apparatus of cancer cells compared to normal cells, and thus can be specifically activated by the acidic Golgi apparatus in cancer cells for effective PTT both ex vivo and in vivo.

Golgi bypass for local delivery of axonal proteins, fact or fiction?

Science.gov (United States)

González, Carolina; Cornejo, Víctor Hugo; Couve, Andrés

2018-04-06

Although translation of cytosolic proteins is well described in axons, much less is known about the synthesis, processing and trafficking of transmembrane and secreted proteins. A canonical rough endoplasmic reticulum or a stacked Golgi apparatus has not been detected in axons, generating doubts about the functionality of a local route. However, axons contain mRNAs for membrane and secreted proteins, translation factors, ribosomal components, smooth endoplasmic reticulum and post-endoplasmic reticulum elements that may contribute to local biosynthesis and plasma membrane delivery. Here we consider the evidence supporting a local secretory system in axons. We discuss exocytic elements and examples of autonomous axonal trafficking that impact development and maintenance. We also examine whether unconventional post-endoplasmic reticulum pathways may replace the canonical Golgi apparatus. Copyright © 2018. Published by Elsevier Ltd.

Secretory granule formation and membrane recycling by the trans-Golgi network in adipokinetic cells of Locusta migratoria in relation to flight and rest.

Science.gov (United States)

Diederen, J H; Vullings, H G

1995-03-01

The influence of flight activity on the formation of secretory granules and the concomitant membrane recycling by the trans-Golgi network in the peptidergic neurosecretory adipokinetic cells of Locusta migratoria was investigated by means of ultrastructural morphometric methods. The patterns of labelling of the trans-Golgi network by the exogenous adsorptive endocytotic tracer wheat-germ agglutinin-conjugated horse-radish peroxidase and by the endogenous marker enzyme acid phosphatase were used as parameters and were measured by an automatic image analysis system. The results show that endocytosed fragments of plasma membrane with bound peroxidase label were transported to the trans-Golgi network and used to build new secretory granules. The amounts of peroxidase and especially of acid phosphatase within the trans-Golgi network showed a strong tendency to be smaller in flight-stimulated cells than in non-stimulated cells. The amounts of acid phosphatase in the immature secretory granules originating from the trans-Golgi network were significantly smaller in stimulated cells. The number of immature secretory granules positive for acid phosphatase tended to be higher in stimulated cells. Thus, flight stimulation of adipokinetic cells for 1 h influences the functioning of the trans-Golgi network; this most probably results in a slight enhancement of the production of secretory granules by the trans-Golgi network.

Blocking variant surface glycoprotein synthesis alters endoplasmic reticulum exit sites/Golgi homeostasis in Trypanosoma brucei.

Science.gov (United States)

Ooi, Cher-Pheng; Smith, Terry K; Gluenz, Eva; Wand, Nadina Vasileva; Vaughan, Sue; Rudenko, Gloria

2018-06-01

The predominant secretory cargo of bloodstream form Trypanosoma brucei is variant surface glycoprotein (VSG), comprising ~10% total protein and forming a dense protective layer. Blocking VSG translation using Morpholino oligonucleotides triggered a precise pre-cytokinesis arrest. We investigated the effect of blocking VSG synthesis on the secretory pathway. The number of Golgi decreased, particularly in post-mitotic cells, from 3.5 ± 0.6 to 2.0 ± 0.04 per cell. Similarly, the number of endoplasmic reticulum exit sites (ERES) in post-mitotic cells dropped from 3.9 ± 0.6 to 2.7 ± 0.1 eight hours after blocking VSG synthesis. The secretory pathway was still functional in these stalled cells, as monitored using Cathepsin L. Rates of phospholipid and glycosylphosphatidylinositol-anchor biosynthesis remained relatively unaffected, except for the level of sphingomyelin which increased. However, both endoplasmic reticulum and Golgi morphology became distorted, with the Golgi cisternae becoming significantly dilated, particularly at the trans-face. Membrane accumulation in these structures is possibly caused by reduced budding of nascent vesicles due to the drastic reduction in the total amount of secretory cargo, that is, VSG. These data argue that the total flux of secretory cargo impacts upon the biogenesis and maintenance of secretory structures and organelles in T. brucei, including the ERES and Golgi. © 2018 The Authors. Traffic published by John Wiley & Sons Ltd.

Chlamydia trachomatis intercepts Golgi-derived sphingolipids through a Rab14-mediated transport required for bacterial development and replication.

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Anahí Capmany

2010-11-01

Full Text Available Chlamydia trachomatis are obligate intracellular bacteria that survive and replicate in a bacterial-modified phagosome called inclusion. As other intracellular parasites, these bacteria subvert the phagocytic pathway to avoid degradation in phagolysosomes and exploit trafficking pathways to acquire both energy and nutrients essential for their survival. Rabs are host proteins that control intracellular vesicular trafficking. Rab14, a Golgi-related Rab, controls Golgi to endosomes transport. Since Chlamydia establish a close relationship with the Golgi apparatus, the recruitment and participation of Rab14 on inclusion development and bacteria growth were analyzed. Time course analysis revealed that Rab14 associated with inclusions by 10 h post infection and was maintained throughout the entire developmental cycle. The recruitment was bacterial protein synthesis-dependent but independent of microtubules and Golgi integrity. Overexpression of Rab14 dominant negative mutants delayed inclusion enlargement, and impaired bacteria replication as determined by IFU. Silencing of Rab14 by siRNA also decreased bacteria multiplication and infectivity. By electron microscopy, aberrant bacteria were observed in cells overexpressing the cytosolic negative Rab14 mutant. Our results showed that Rab14 facilitates the delivery of sphingolipids required for bacterial development and replication from the Golgi to chlamydial inclusions. Novel anti-chlamydial therapies could be developed based on the knowledge of how bacteria subvert host vesicular transport events through Rabs manipulation.

Chlamydia trachomatis intercepts Golgi-derived sphingolipids through a Rab14-mediated transport required for bacterial development and replication.

Science.gov (United States)

Capmany, Anahí; Damiani, María Teresa

2010-11-22

Chlamydia trachomatis are obligate intracellular bacteria that survive and replicate in a bacterial-modified phagosome called inclusion. As other intracellular parasites, these bacteria subvert the phagocytic pathway to avoid degradation in phagolysosomes and exploit trafficking pathways to acquire both energy and nutrients essential for their survival. Rabs are host proteins that control intracellular vesicular trafficking. Rab14, a Golgi-related Rab, controls Golgi to endosomes transport. Since Chlamydia establish a close relationship with the Golgi apparatus, the recruitment and participation of Rab14 on inclusion development and bacteria growth were analyzed. Time course analysis revealed that Rab14 associated with inclusions by 10 h post infection and was maintained throughout the entire developmental cycle. The recruitment was bacterial protein synthesis-dependent but independent of microtubules and Golgi integrity. Overexpression of Rab14 dominant negative mutants delayed inclusion enlargement, and impaired bacteria replication as determined by IFU. Silencing of Rab14 by siRNA also decreased bacteria multiplication and infectivity. By electron microscopy, aberrant bacteria were observed in cells overexpressing the cytosolic negative Rab14 mutant. Our results showed that Rab14 facilitates the delivery of sphingolipids required for bacterial development and replication from the Golgi to chlamydial inclusions. Novel anti-chlamydial therapies could be developed based on the knowledge of how bacteria subvert host vesicular transport events through Rabs manipulation.

Role of the Small GTPase Rho3 in Golgi/Endosome trafficking through functional interaction with adaptin in Fission Yeast.

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Ayako Kita

Full Text Available BACKGROUND: We had previously identified the mutant allele of apm1(+ that encodes a homolog of the mammalian µ1A subunit of the clathrin-associated adaptor protein-1 (AP-1 complex, and we demonstrated the role of Apm1 in Golgi/endosome trafficking, secretion, and vacuole fusion in fission yeast. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we isolated rho3(+, which encodes a Rho-family small GTPase, an important regulator of exocystosis, as a multicopy-suppressor of the temperature-sensitive growth of the apm1-1 mutant cells. Overexpression of Rho3 suppressed the Cl(- sensitivity and immunosuppressant sensitivity of the apm1-1 mutant cells. Overexpression of Rho3 also suppressed the fragmentation of vacuoles, and the accumulation of v-SNARE Syb1 in Golgi/endosomes and partially suppressed the defective secretion associated with apm1-deletion cells. Notably, electron microscopic observation of the rho3-deletion cells revealed the accumulation of abnormal Golgi-like structures, vacuole fragmentation, and accumulation of secretory vesicles; these phenotypes were very similar to those of the apm1-deletion cells. Furthermore, the rho3-deletion cells and apm1-deletion cells showed very similar phenotypic characteristics, including the sensitivity to the immunosuppressant FK506, the cell wall-damaging agent micafungin, Cl(-, and valproic acid. Green fluorescent protein (GFP-Rho3 was localized at Golgi/endosomes as well as the plasma membrane and division site. Finally, Rho3 was shown to form a complex with Apm1 as well as with other subunits of the clathrin-associated AP-1 complex in a GTP- and effector domain-dependent manner. CONCLUSIONS/SIGNIFICANCE: Taken together, our findings reveal a novel role of Rho3 in the regulation of Golgi/endosome trafficking and suggest that clathrin-associated adaptor protein-1 and Rho3 co-ordinate in intracellular transport in fission yeast. To the best of our knowledge, this study provides the first evidence

Vesicular transport of progeny parvovirus particles through ER and Golgi regulates maturation and cytolysis.

Science.gov (United States)

Bär, Séverine; Rommelaere, Jean; Nüesch, Jürg P F

2013-09-01

Progeny particles of non-enveloped lytic parvoviruses were previously shown to be actively transported to the cell periphery through vesicles in a gelsolin-dependent manner. This process involves rearrangement and destruction of actin filaments, while microtubules become protected throughout the infection. Here the focus is on the intracellular egress pathway, as well as its impact on the properties and release of progeny virions. By colocalization with cellular marker proteins and specific modulation of the pathways through over-expression of variant effector genes transduced by recombinant adeno-associated virus vectors, we show that progeny PV particles become engulfed into COPII-vesicles in the endoplasmic reticulum (ER) and are transported through the Golgi to the plasma membrane. Besides known factors like sar1, sec24, rab1, the ERM family proteins, radixin and moesin play (an) essential role(s) in the formation/loading and targeting of virus-containing COPII-vesicles. These proteins also contribute to the transport through ER and Golgi of the well described analogue of cellular proteins, the secreted Gaussia luciferase in absence of virus infection. It is therefore likely that radixin and moesin also serve for a more general function in cellular exocytosis. Finally, parvovirus egress via ER and Golgi appears to be necessary for virions to gain full infectivity through post-assembly modifications (e.g. phosphorylation). While not being absolutely required for cytolysis and progeny virus release, vesicular transport of parvoviruses through ER and Golgi significantly accelerates these processes pointing to a regulatory role of this transport pathway.

Adiponectin release and insulin receptor targeting share trans-Golgi-dependent endosomal trafficking routes

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Maria Rödiger

2018-02-01

Full Text Available Objective: Intracellular vesicle trafficking maintains cellular structures and functions. The assembly of cargo-laden vesicles at the trans-Golgi network is initiated by the ARF family of small GTPases. Here, we demonstrate the role of the trans-Golgi localized monomeric GTPase ARFRP1 in endosomal-mediated vesicle trafficking of mature adipocytes. Methods: Control (Arfrp1flox/flox and inducible fat-specific Arfrp1 knockout (Arfrp1iAT−/− mice were metabolically characterized. In vitro experiments on mature 3T3-L1 cells and primary mouse adipocytes were conducted to validate the impact of ARFRP1 on localization of adiponectin and the insulin receptor. Finally, secretion and transferrin-based uptake and recycling assays were performed with HeLa and HeLa M-C1 cells. Results: We identified the ARFRP1-based sorting machinery to be involved in vesicle trafficking relying on the endosomal compartment for cell surface delivery. Secretion of adiponectin from fat depots was selectively reduced in Arfrp1iAT−/− mice, and Arfrp1-depleted 3T3-L1 adipocytes revealed an accumulation of adiponectin in Rab11-positive endosomes. Plasma adiponectin deficiency of Arfrp1iAT−/− mice resulted in deteriorated hepatic insulin sensitivity, increased gluconeogenesis and elevated fasting blood glucose levels. Additionally, the insulin receptor, undergoing endocytic recycling after ligand binding, was less abundant at the plasma membrane of adipocytes lacking Arfrp1. This had detrimental effects on adipose insulin signaling, followed by insufficient suppression of basal lipolytic activity and impaired adipose tissue expansion. Conclusions: Our findings suggest that adiponectin secretion and insulin receptor surface targeting utilize the same post-Golgi trafficking pathways that are essential for an appropriate systemic insulin sensitivity and glucose homeostasis. Keywords: Adiponectin, ARFRP1, Exocytosis, Insulin receptor, trans-Golgi

The GTPase Rab43 Controls the Anterograde ER-Golgi Trafficking and Sorting of GPCRs

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Chunman Li

2017-10-01

Full Text Available G-protein-coupled receptors (GPCRs constitute the largest superfamily of cell-surface signaling proteins. However, mechanisms underlying their surface targeting and sorting are poorly understood. Here, we screen the Rab family of small GTPases in the surface transport of multiple GPCRs. We find that manipulation of Rab43 function significantly alters the surface presentation and signaling of all GPCRs studied without affecting non-GPCR membrane proteins. Rab43 specifically regulates the transport of nascent GPCRs from the endoplasmic reticulum (ER to the Golgi. More interestingly, Rab43 directly interacts with GPCRs in an activation-dependent fashion. The Rab43-binding domain identified in the receptors effectively converts non-GPCR membrane protein transport into a Rab43-dependent pathway. These data reveal a crucial role for Rab43 in anterograde ER-Golgi transport of nascent GPCRs, as well as the ER sorting of GPCR members by virtue of its ability to interact directly.

Role of myristoylation in membrane attachment and function of G alpha i-3 on Golgi membranes.

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Brand, S H; Holtzman, E J; Scher, D A; Ausiello, D A; Stow, J L

1996-05-01

Heterotrimeric G protein alpha-subunits localized on the cytoplasmic face of Golgi membranes are involved in regulating vesicle trafficking and protein secretion. We investigated the role of myristoylation in attachment of the G alpha i-3 subunit to Golgi membranes. G alpha i-3 was epitope-tagged by insertion of a FLAG sequence at an NH2-terminal site predicted to interfere with myristoylation, and the resulting NT-alpha i-3 construct was stably transfected and expressed in polarized epithelial LLC-PK1 cells. Metabolic labeling confirmed that the translation product of NT-alpha i-3 was not myristoylated. In contrast to endogenous G alpha 1-3, which is tightly bound to Golgi membranes, the unmyristoylated FLAG-tagged NT-alpha i-3 did not attach to membranes; it was localized by immunofluorescence in the cytoplasm of LLC-PK1 cells and was detected only in the cytosol fraction of cell homogenates. Pertussis toxin-dependent ADP-ribosylation was used to test the ability of NT-alpha i-3 to interact with membrane-bound beta gamma-subunits. In both in vitro and in vivo assays, cytosolic NT-alpha i-3 alone was not ADP-ribosylated, although in the presence of membranes it could interact with G beta gamma-subunits to form heterotrimers. The expression of NT-alpha i-3 in LLC-PK1 cells altered the rate of basolateral secretion of sulfated proteoglycans, consistent with the demonstrated function of endogenous G alpha i-3. These data are consistent with a model in which G alpha i-3 utilizes NH2-terminal myristoylation to bind to Golgi membranes and to maximize its interaction with G beta gamma-subunits. Furthermore, our results show that stable attachment of G alpha i-3 to Golgi membranes is not required for it to participate as a regulatory element in vesicle trafficking in the secretory pathway.

Analysis of thick brain sections by obverse-reverse computer microscopy: application of a new, high clarity Golgi-Nissl stain.

Science.gov (United States)

Glaser, E M; Van der Loos, H

1981-08-01

Exceptionally clear Golgi-Nissl sections of 300 micron thickness have been morphometrically studied by light microscopy using oil immersion objectives. The clarity results from a new variation of a staining procedure that combines Golgi and Nissl images in one section. A viewing technique has been developed that permits a histologic preparation to be examined from its obverse (or normally viewed) side and its reverse (or under) side. The technique was designed for use with a computer microscope but can be employed with any light microscope whose stage position can be measured within 100 micron. Sections thicker than 300 micron can be studied dependent on the working distance of the objective lens, provided that the clarity of the material permits it.

Evidence that proliferation of golgi apparatus depends on both de novo generation from the endoplasmic reticulum and formation from pre-existing stacks during the growth of tobacco BY-2 cells.

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Abiodun, Moses Olabiyi; Matsuoka, Ken

2013-04-01

In higher plants, the numbers of cytoplasmic-distributed Golgi stacks differ based on function, age and cell type. It has not been clarified how the numbers are controlled, whether all the Golgi apparatus in a cell function equally and whether the increase in Golgi number is a result of the de novo formation from the endoplasmic reticulum (ER) or fission of pre-existing stacks. A tobacco prolyl 4-hydroxylase (NtP4H1.1), which is a cis-Golgi-localizing type II membrane protein, was tagged with a photoconvertible fluorescent protein, mKikGR (monomeric Kikume green red), and expressed in tobacco bright yellow 2 (BY-2) cells. Transformed cells were exposed to purple light to convert the fluorescence from green to red. A time-course analysis after the conversion revealed a progressive increase in green puncta and a decrease in the red puncta. From 3 to 6 h, we observed red, yellow and green fluorescent puncta corresponding to pre-existing Golgi; Golgi containing both pre-existing and newly synthesized protein; and newly synthesized Golgi. Analysis of the number and fluorescence of Golgi at different phases of the cell cycle suggested that an increase in Golgi number with both division and de novo synthesis occurred concomitantly with DNA replication. Investigation with different inhibitors suggested that the formation of new Golgi and the generation of Golgi containing both pre-existing and newly synthesized protein are mediated by different machineries. These results and modeling based on quantified results indicate that the Golgi apparatuses in tobacco BY-2 cells are not uniform and suggest that both de novo synthesis from the ER and Golgi division contribute almost equally to the increase in proliferating cells.

Live-cell imaging of dual-labeled Golgi stacks in tobacco BY-2 cells reveals similar behaviors for different cisternae during movement and brefeldin A treatment.

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Madison, Stephanie L; Nebenführ, Andreas

2011-09-01

In plant cells, the Golgi apparatus consists of numerous stacks that, in turn, are composed of several flattened cisternae with a clear cis-to-trans polarity. During normal functioning within living cells, this unusual organelle displays a wide range of dynamic behaviors such as whole stack motility, constant membrane flux through the cisternae, and Golgi enzyme recycling through the ER. In order to further investigate various aspects of Golgi stack dynamics and integrity, we co-expressed pairs of established Golgi markers in tobacco BY-2 cells to distinguish sub-compartments of the Golgi during monensin treatments, movement, and brefeldin A (BFA)-induced disassembly. A combination of cis and trans markers revealed that Golgi stacks remain intact as they move through the cytoplasm. The Golgi stack orientation during these movements showed a slight preference for the cis side moving ahead, but trans cisternae were also found at the leading edge. During BFA treatments, the different sub-compartments of about half of the observed stacks fused with the ER sequentially; however, no consistent order could be detected. In contrast, the ionophore monensin resulted in swelling of trans cisternae while medial and particularly cis cisternae were mostly unaffected. Our results thus demonstrate a remarkable equivalence of the different cisternae with respect to movement and BFA-induced fusion with the ER. In addition, we propose that a combination of dual-label fluorescence microscopy and drug treatments can provide a simple alternative approach to the determination of protein localization to specific Golgi sub-compartments.

Retention in the Golgi apparatus and expression on the cell surface of Cfr/Esl-1/Glg-1/MG-160 are regulated by two distinct mechanisms.

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Miyaoka, Yuichiro; Kato, Hidenori; Ebato, Kazuki; Saito, Shigeru; Miyata, Naoko; Imamura, Toru; Miyajima, Atsushi

2011-11-15

Cfr (cysteine-rich fibroblast growth factor receptor) is an Fgf (fibroblast growth factor)-binding protein without a tyrosine kinase. We have shown previously that Cfr is involved in Fgf18 signalling via Fgf receptor 3c. However, as Cfr is also known as Glg (Golgi apparatus protein)-1 or MG-160 and occurs in the Golgi apparatus, it remains unknown how the distribution of Cfr is regulated. In the present study, we performed a mutagenic analysis of Cfr to show that two distinct regions contribute to its distribution and stability. First, the C-terminal region retains Cfr in the Golgi apparatus. Secondly, the Cfr repeats in the extracellular juxtamembrane region destabilizes Cfr passed through the Golgi apparatus. This destabilization does not depend on the cleavage and secretion of the extracellular domain of Cfr. Furthermore, we found that Cfr with a GPI (glycosylphosphatidylinositol) anchor was predominantly expressed on the cell surface in Ba/F3 cells and affected Fgf18 signalling in a similar manner to the full-length Cfr, indicating that the interaction of Cfr with Fgfs on the cell surface is important for its function in Fgf signalling. These results suggest that the expression of Cfr in the Golgi apparatus and on the plasma membrane is finely tuned through two distinct mechanisms for exhibiting different functions.

Proton accumulation and ATPase activity in Golgi apparatus-enriched vesicles from rat liver

International Nuclear Information System (INIS)

Yeh, H.I.; van Rossum, G.D.

1991-01-01

We have studied the mechanism by which liver Golgi apparatus maintains the acidity of its contents, using a subcellular fraction from rat liver highly enriched in Golgi marker enzymes. Proton accumulation (measured by quenching of acridine-orange fluorescence) and anion-dependent ATPase were characterized and compared. Maximal ATPase and proton accumulation required ATP; GTP and other nucleotides gave 10% to 30% of maximal activity. Among anions, Cl- and Br- approximately doubled the activities; others were much less effective. Half-maximal increase of ATPase and H+ uptake required 55 mmol/L and 27 mmol/L Cl-, respectively. In predominantly chloride media, SCN- and NO3- markedly inhibited H+ uptake. Nitrate competitively inhibited both the chloride-dependent ATPase (apparent Ki 6 mmol/L) and proton uptake (apparent Ki 2 mmol/L). Nitrate and SCN- also inhibited uptake of 36Cl. Replacing K+ with Na+ had no effect on the initial rate of proton uptake but somewhat reduced the steady state attained. Replacement of K+ with NH4+ and choline reduced proton uptake without affecting ATPase. The ATPase and H+ uptake were supported equally well by Mg2+ or Mn2+. The ATPase was competitively inhibited by 4-acetamido-4'-isothiocyano-stilbene-2,2'-disulfonic acid (apparent Ki 39 mumol/L). Other agents inhibiting both H+ uptake and ATPase were N-ethylmaleimide, N,N'-dicyclohexylcarbodiimide, chlorpromazine, diethylstilbestrol, Zn2+, Co2+ and Cu2+. In the Cl- medium, accumulated protons were released by ionophores at the relative rates, monensin = nigericin greater than valinomycin greater than carbonyl cyanide mchlorophenylhydrazone; the last of these also reduced ATPase activity. In the absence of Cl-, monensin and valinomycin both stimulated the ATPase. These results show a close association between ATPase activity and acidification of liver Golgi vesicles

Conditional deletion of Cadherin 13 perturbs Golgi cells and disrupts social and cognitive behaviors.

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Tantra, M; Guo, L; Kim, J; Zainolabidin, N; Eulenburg, V; Augustine, G J; Chen, A I

2018-02-15

Inhibitory interneurons mediate the gating of synaptic transmission and modulate the activities of neural circuits. Disruption of the function of inhibitory networks in the forebrain is linked to impairment of social and cognitive behaviors, but the involvement of inhibitory interneurons in the cerebellum has not been assessed. We found that Cadherin 13 (Cdh13), a gene implicated in autism spectrum disorder and attention-deficit hyperactivity disorder, is specifically expressed in Golgi cells within the cerebellar cortex. To assess the function of Cdh13 and utilize the manipulation of Cdh13 expression in Golgi cells as an entry point to examine cerebellar-mediated function, we generated mice carrying Cdh13-floxed alleles and conditionally deleted Cdh13 with GlyT2::Cre mice. Loss of Cdh13 results in a decrease in the expression/localization of GAD67 and reduces spontaneous inhibitory postsynaptic current (IPSC) in cerebellar Golgi cells without disrupting spontaneous excitatory postsynaptic current (EPSC). At the behavioral level, loss of Cdh13 in the cerebellum, piriform cortex and endopiriform claustrum have no impact on gross motor coordination or general locomotor behaviors, but leads to deficits in cognitive and social abilities. Mice lacking Cdh13 exhibit reduced cognitive flexibility and loss of preference for contact region concomitant with increased reciprocal social interactions. Together, our findings show that Cdh13 is critical for inhibitory function of Golgi cells, and that GlyT2::Cre-mediated deletion of Cdh13 in non-executive centers of the brain, such as the cerebellum, may contribute to cognitive and social behavioral deficits linked to neurological disorders. © 2018 The Authors. Genes, Brain and Behavior published by International Behavioural and Neural Genetics Society and John Wiley & Sons Ltd.

Ceramide transport from endoplasmic reticulum to Golgi apparatus is not vesicle-mediated

NARCIS (Netherlands)

Kok, JW; Babia, T; Klappe, K; Egea, G; Hoekstra, D

1998-01-01

Ceramide (Cer) transfer from the endoplasmic reticulum (ER) to the Golgi apparatus was measured under conditions that block vesicle-mediated protein transfer. This was done either in intact cells by reducing the incubation temperature to 15 degrees C, or in streptolysin O-permeabilized cells by

Proliferation of the Golgi apparatus in tobacco BY-2 cells during cell proliferation after release from the stationary phase of growth.

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Abiodun, Moses; Matsuoka, Ken

2013-08-01

We have recently developed a new method aimed at mass photo-conversion of photo-convertible fluorescence protein (PFP) fluorescence in transformed tobacco BY-2 cells. Using this method we reported recently that the Golgi apparatus is generated by the de novo formation from ER and the division of pre-existing Golgi stacks with similar extents In this work we report that the proliferation of the Golgi apparatus in tobacco cells that enter the growing cycle from the non-dividing cycle is quite similar to that in rapidly growing cells and that de novo formation from the ER and division of pre-existing stacks seems to contribute almost equally to the proliferation.

Modulating Endoplasmic Reticulum-Golgi Cargo Receptors for Improving Secretion of Carrier-Fused Heterologous Proteins in the Filamentous Fungus Aspergillus oryzae

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Hoang, Huy-Dung; Maruyama, Jun-ichi

2014-01-01

Filamentous fungi are excellent hosts for industrial protein production due to their superior secretory capacity; however, the yield of heterologous eukaryotic proteins is generally lower than that of fungal or endogenous proteins. Although activating protein folding machinery in the endoplasmic reticulum (ER) improves the yield, the importance of intracellular transport machinery for heterologous protein secretion is poorly understood. Here, using Aspergillus oryzae as a model filamentous fungus, we studied the involvement of two putative lectin-like cargo receptors, A. oryzae Vip36 (AoVip36) and AoEmp47, in the secretion of heterologous proteins expressed in fusion with the endogenous enzyme α-amylase as the carrier. Fluorescence microscopy revealed that mDsRed-tagged AoVip36 localized in the Golgi compartment, whereas AoEmp47 showed localization in both the ER and the Golgi compartment. Deletion of AoVip36 and AoEmp47 improved heterologous protein secretion, but only AoVip36 deletion had a negative effect on the secretion of α-amylase. Analysis of ER-enriched cell fractions revealed that AoVip36 and AoEmp47 were involved in the retention of heterologous proteins in the ER. However, the overexpression of each cargo receptor had a different effect on heterologous protein secretion: AoVip36 enhanced the secretion, whereas AoEmp47 promoted the intracellular retention. Taken together, our data suggest that AoVip36 and AoEmp47 hinder the secretion of heterologous proteins by promoting their retention in the ER but that AoVip36 also promotes the secretion of heterologous proteins. Moreover, we found that genetic deletion of these putative ER-Golgi cargo receptors significantly improves heterologous protein production. The present study is the first to propose that ER-Golgi transport is a bottleneck for heterologous protein production in filamentous fungi. PMID:25362068

Hsp20 Protects against Oxygen-Glucose Deprivation/Reperfusion-Induced Golgi Fragmentation and Apoptosis through Fas/FasL Pathway

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Bingwu Zhong

2015-01-01

Full Text Available Cerebral ischemia-reperfusion injury plays an important role in the development of tissue injury after acute ischemic stroke. Finding effective neuroprotective agents has become a priority in the treatment of ischemic stroke. The Golgi apparatus (GA is a pivotal organelle and its protection is an attractive target in the treatment of cerebral ischemia-reperfusion injury. Protective effects of Hsp20, a potential cytoprotective agent due to its chaperone-like activity and involvement in regulation of many vital processes, on GA were assessed in an ischemia-reperfusion injury model. Mouse neuroblastoma Neuro2a (N2a cells were subjected to oxygen-glucose deprivation/reperfusion (OGDR insult. OGDR induces Golgi fragmentation, apoptosis, and p115 cleavage in N2a cells. However, transfection with Hsp20 significantly attenuates OGDR-induced Golgi fragmentation and apoptosis. Hsp20 interacts with Bax, decreases FasL and Bax expression, and inhibits caspases 3 and p115 cleavage in N2a cells exposed to OGDR. Our data demonstrate that increased Hsp20 expression protects against OGDR-induced Golgi fragmentation and apoptosis, likely through interaction with Bax and subsequent amelioration of the OGDR-induced elevation in p115 cleavage via the Fas/FasL signaling pathway. This neuroprotective potential of Hsp20 against OGDR insult and the underlying mechanism will pave the way for its potential clinical application for cerebral ischemia-reperfusion related disorders.

Neutral sphingomyelinase (SMPD3) deficiency disrupts the Golgi secretory pathway and causes growth inhibition

Science.gov (United States)

Stoffel, Wilhelm; Hammels, Ina; Jenke, Bitta; Binczek, Erika; Schmidt-Soltau, Inga; Brodesser, Susanne; Schauss, Astrid; Etich, Julia; Heilig, Juliane; Zaucke, Frank

2016-01-01

Systemic loss of neutral sphingomyelinase (SMPD3) in mice leads to a novel form of systemic, juvenile hypoplasia (dwarfism). SMPD3 deficiency in mainly two growth regulating cell types contributes to the phenotype, in chondrocytes of skeletal growth zones to skeletal malformation and chondrodysplasia, and in hypothalamic neurosecretory neurons to systemic hypothalamus–pituitary–somatotropic hypoplasia. The unbiased smpd3−/− mouse mutant and derived smpd3−/− primary chondrocytes were instrumental in defining the enigmatic role underlying the systemic and cell autonomous role of SMPD3 in the Golgi compartment. Here we describe the unprecedented role of SMPD3. SMPD3 deficiency disrupts homeostasis of sphingomyelin (SM), ceramide (Cer) and diacylglycerol (DAG) in the Golgi SMPD3-SMS1 (SM-synthase1) cycle. Cer and DAG, two fusogenic intermediates, modify the membrane lipid bilayer for the initiation of vesicle formation and transport. Dysproteostasis, unfolded protein response, endoplasmic reticulum stress and apoptosis perturb the Golgi secretory pathway in the smpd3−/− mouse. Secretion of extracellular matrix proteins is arrested in chondrocytes and causes skeletal malformation and chondrodysplasia. Similarly, retarded secretion of proteo-hormones in hypothalamic neurosecretory neurons leads to hypothalamus induced combined pituitary hormone deficiency. SMPD3 in the regulation of the protein vesicular secretory pathway may become a diagnostic target in the etiology of unknown forms of juvenile growth and developmental inhibition. PMID:27882938

Nucleocytoplasmic shuttling of STK16 (PKL12), a Golgi-resident serine/threonine kinase involved in VEGF expression regulation

International Nuclear Information System (INIS)

Guinea, Barbara; Ligos, Jose Manuel; Lain de Lera, Teresa; Martin-Caballero, Juan; Flores, Juana; Gonzalez de la Pena, Manuel; Garcia-Castro, Javier; Bernad, Antonio

2006-01-01

PKL12/STK16 protein is the first identified mammalian member of a ser/thr kinase subfamily that is conserved across several kingdoms, with a broad expression pattern in murine tissues and cell types. Endogenous STK16 subcellular localization was evaluated by indirect immunofluorescence in NIH/3T3 and NRK cells, demonstrating a Golgi-associated pattern that appears to be independent of signals provided by integrin pathways. When cells were treated with brefeldin A (BFA) or nocodazole, drugs that promote Golgi disorganization, we observed STK16 translocation to the nuclear compartment. Constitutive overexpression of this protein by retroviral vectors also promotes accumulation of STK16 in the nuclear compartment, as shown by subfractionation studies. A kinase-dead STK16 mutant (E202A) was used to demonstrate that both the Golgi association and the nuclear translocation capabilities seem to be independent of the STK16 kinase activity. In addition, we show that STK16 overexpression in several cell lines enhances their capacity to produce and secrete VEGF. To confirm these data in vivo, we injected tumor cells overexpressing STK16 into immunodeficient BALBc/SCID mice. HT1080-derived tumors overexpressing STK16 showed increased volume and number of blood vessels compared to controls. Altogether, these data concur with previous reports suggesting a potential role for STK16 as a transcriptional co-activator

Dynamin-like protein 1 at the Golgi complex: A novel component of the sorting/targeting machinery en route to the plasma membrane

International Nuclear Information System (INIS)

Bonekamp, Nina A.; Vormund, Kerstin; Jacob, Ralf; Schrader, Michael

2010-01-01

The final step in the liberation of secretory vesicles from the trans-Golgi network (TGN) involves the mechanical action of the large GTPase dynamin as well as conserved dynamin-independent fission mechanisms, e.g. mediated by Brefeldin A-dependent ADP-ribosylated substrate (BARS). Another member of the dynamin family is the mammalian dynamin-like protein 1 (DLP1/Drp1) that is known to constrict and tubulate membranes, and to divide mitochondria and peroxisomes. Here, we examined a potential role for DLP1 at the Golgi complex. DLP1 localized to the Golgi complex in some but not all cell lines tested, thus explaining controversial reports on its cellular distribution. After silencing of DLP1, an accumulation of the apical reporter protein YFP-GL-GPI, but not the basolateral reporter VSVG-SP-GFP at the Golgi complex was observed. A reduction in the transport of YFP-GL-GPI to the plasma membrane was confirmed by surface immunoprecipitation and TGN-exit assays. In contrast, YFP-GL-GPI trafficking was not disturbed in cells silenced for BARS, which is involved in basolateral sorting and trafficking of VSVG-SP-GFP in COS-7 cells. Our data indicate a new role for DLP1 at the Golgi complex and thus a role for DLP1 as a novel component of the apical sorting machinery at the TGN is discussed.

Determinants for membrane association and permeabilization of the coxsackievirus 2B protein and the identification of the Golgi complex as the target organelle.

Science.gov (United States)

de Jong, Arjan S; Wessels, Els; Dijkman, Henri B P M; Galama, Jochem M D; Melchers, Willem J G; Willems, Peter H G M; van Kuppeveld, Frank J M

2003-01-10

The 2B protein of enterovirus is responsible for the alterations in the permeability of secretory membranes and the plasma membrane in infected cells. The structural requirements for the membrane association and the subcellular localization of this essential virus protein, however, have not been defined. Here, we provide evidence that the 2B protein is an integral membrane protein in vivo that is predominantly localized at the Golgi complex upon individual expression. Addition of organelle-specific targeting signals to the 2B protein revealed that the Golgi localization is an absolute prerequisite for the ability of the protein to modify plasma membrane permeability. Expression of deletion mutants and heterologous proteins containing specific domains of the 2B protein demonstrated that each of the two hydrophobic regions could mediate membrane binding individually. However, the presence of both hydrophobic regions was required for the correct membrane association, efficient Golgi targeting, and the membrane-permeabilizing activity of the 2B protein, suggesting that the two hydrophobic regions are cooperatively involved in the formation of a membrane-integral complex. The formation of membrane-integral pores by the 2B protein in the Golgi complex and the possible mechanism by which a Golgi-localized virus protein modifies plasma membrane permeability are discussed.

Short length transmembrane domains having voluminous exoplasmic halves determine retention of Type II membrane proteins in the Golgi complex

OpenAIRE

Quiroga, Rodrigo; Trenchi, Alejandra; Gonzalez Montoro, Ayelén; Valdez, Javier Esteban; Maccioni, Hugo Jose Fernando

2017-01-01

It is still unclear why some proteins that travel along the secretory pathway are retained in the Golgi complex whereas others make their way to the plasma membrane. Recent bioinformatic analyses on a large number of single-spanning membrane proteins support the hypothesis that specific features of the transmembrane domain (TMD) are relevant to the sorting of these proteins to particular organelles. Here we experimentally test this hypothesis for Golgi and plasma membrane proteins. Using the ...

GABARAP activates ULK1 and traffics from the centrosome dependent on Golgi partners WAC and GOLGA2/GM130

OpenAIRE

Joachim, Justin; Tooze, Sharon A.

2016-01-01

ABSTRACT WAC and GOLGA2/GM130 are 2 Golgi proteins that affect autophagy; however, their mechanism of action was unknown. We have shown that WAC binding to GOLGA2 at the Golgi displaces GABARAP from GOLGA2 to allow the maintenance of a nonlipidated centrosomal GABARAP pool. Centrosomal GABARAP can traffic to autophagic structures during starvation. In addition GABARAP specifically promotes ULK1 activation and this is independent of GABARAP lipidation but likely requires a LIR-mediated GABARAP...

Quantitative electron microscopical autoradiography of calcium during dentinogenesis

Energy Technology Data Exchange (ETDEWEB)

Nagai, Y [Tokyo Dental Coll. (Japan); Frank, R M

1975-03-01

/sup 45/Ca migration from the dental papilla and the odontablasts towards predentin and dentin has been studied through electron microscopical autoradiography in toothgerms of newborn cats. A quantitative procedure was applied to the study of the /sup 45/Ca migration in dentinogenesis. Two pathways of almost identical importance have been demonstrated. The direct pathway followed the intercellular spaces of the dental papilla and of the odontoblasts and reached the dentin via predentin. The second road, after passage through the intercellular spaces of the dental papilla, consisted of an intracellular migration through the odontoblast. The mitochondria and the golgi apparatus were progressively the most labelet at 5 min., 30 min. and 1 h. after intravenous injection. The calcium diffused into the odontablastic process without being associated with the dense granule. At 6 hours, maximum radioactivity was observed in the intertubular dentin.

Hepatic trans-Golgi action coordinated by the GTPase ARFRP1 is crucial for lipoprotein lipidation and assembly[S

Science.gov (United States)

Hesse, Deike; Radloff, Katrin; Jaschke, Alexander; Lagerpusch, Merit; Chung, Bomee; Tailleux, Anne; Staels, Bart; Schürmann, Annette

2014-01-01

The liver is a major organ in whole body lipid metabolism and malfunctioning can lead to various diseases including dyslipidemia, fatty liver disease, and type 2 diabetes. Triglycerides and cholesteryl esters are packed in the liver as very low density lipoproteins (VLDLs). Generation of these lipoproteins is initiated in the endoplasmic reticulum and further maturation likely occurs in the Golgi. ADP-ribosylation factor-related protein 1 (ARFRP1) is a small trans-Golgi-associated guanosine triphosphatase (GTPase) that regulates protein sorting and is required for chylomicron lipidation and assembly in the intestine. Here we show that the hepatocyte-specific deletion of Arfrp1 (Arfrp1liv−/−) results in impaired VLDL lipidation leading to reduced plasma triglyceride levels in the fasted state as well as after inhibition of lipoprotein lipase activity by Triton WR-1339. In addition, the concentration of ApoC3 that comprises 40% of protein mass of secreted VLDLs is markedly reduced in the plasma of Arfrp1liv−/− mice but accumulates in the liver accompanied by elevated triglycerides. Fractionation of Arfrp1liv−/− liver homogenates reveals more ApoB48 and a lower concentration of triglycerides in the Golgi compartments than in the corresponding fractions from control livers. In conclusion, ARFRP1 and the Golgi apparatus play an important role in lipoprotein maturation in the liver by influencing lipidation and assembly of proteins to the lipid particles. PMID:24186947

Golgi localized barley MTP8 proteins facilitate Mn transport

DEFF Research Database (Denmark)

Pedas, Pai Rosager; Schiller, Michaela; Hegelund, Josefine Nymark

2014-01-01

Many metabolic processes in plants are regulated by manganese (Mn) but limited information is available on the molecular mechanisms controlling cellular Mn homeostasis. In this study, a yeast assay was used to isolate and characterize two genes, MTP8.1 and MTP8.2 , which encode membrane...... in yeast, MTP8.1 and MTP8.2 were found to be Mn transporters catalysing Mn efflux in a similar manner as the Golgi localized endogenous yeast protein Pmr1p. The level of MTP8.1 transcripts in barley roots increased with external Mn supply ranging from deficiency to toxicity, while MTP8.2 transcripts...

GABARAP activates ULK1 and traffics from the centrosome dependent on Golgi partners WAC and GOLGA2/GM130.

Science.gov (United States)

Joachim, Justin; Tooze, Sharon A

2016-05-03

WAC and GOLGA2/GM130 are 2 Golgi proteins that affect autophagy; however, their mechanism of action was unknown. We have shown that WAC binding to GOLGA2 at the Golgi displaces GABARAP from GOLGA2 to allow the maintenance of a nonlipidated centrosomal GABARAP pool. Centrosomal GABARAP can traffic to autophagic structures during starvation. In addition GABARAP specifically promotes ULK1 activation and this is independent of GABARAP lipidation but likely requires a LIR-mediated GABARAP-ULK1 interaction.

PI3K class II α regulates δ-opioid receptor export from the trans-Golgi network.

Science.gov (United States)

Shiwarski, Daniel J; Darr, Marlena; Telmer, Cheryl A; Bruchez, Marcel P; Puthenveedu, Manojkumar A

2017-08-01

The interplay between signaling and trafficking by G protein-coupled receptors (GPCRs) has focused mainly on endocytic trafficking. Whether and how surface delivery of newly synthesized GPCRs is regulated by extracellular signals is less understood. Here we define a signaling-regulated checkpoint at the trans -Golgi network (TGN) that controls the surface delivery of the delta opioid receptor (δR). In PC12 cells, inhibition of phosphoinositide-3 kinase (PI3K) activity blocked export of newly synthesized δR from the Golgi and delivery to the cell surface, similar to treatment with nerve growth factor (NGF). Depletion of class II phosphoinositide-3 kinase α (PI3K C2A), but not inhibition of class I PI3K, blocked δR export to comparable levels and attenuated δR-mediated cAMP inhibition. NGF treatment displaced PI3K C2A from the Golgi and optogenetic recruitment of the PI3K C2A kinase domain to the TGN-induced δR export downstream of NGF. Of importance, PI3K C2A expression promotes export of endogenous δR in primary trigeminal ganglion neurons. Taken together, our results identify PI3K C2A as being required and sufficient for δR export and surface delivery in neuronal cells and suggest that it could be a key modulator of a novel Golgi export checkpoint that coordinates GPCR delivery to the surface. © 2017 Shiwarski et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Endoplasmic reticulum-to-Golgi transitions upon herpes virus infection [version 2; referees: 1 approved, 3 approved with reservations

Directory of Open Access Journals (Sweden)

Peter Wild

2018-02-01

Full Text Available Background: Herpesvirus capsids are assembled in the nucleus, translocated to the perinuclear space by budding, acquiring tegument and envelope, or released to the cytoplasm via impaired nuclear envelope. One model proposes that envelopment, “de-envelopment” and “re-envelopment” is essential for production of infectious virus. Glycoproteins gB/gH were reported to be essential for de-envelopment, by fusion of the “primary” envelope with the outer nuclear membrane. Yet, a high proportion of enveloped virions generated from genomes with deleted gB/gH were found in the cytoplasm and extracellular space, suggesting the existence of alternative exit routes. Methods: We investigated the relatedness between the nuclear envelope and membranes of the endoplasmic reticulum and Golgi complex, in cells infected with either herpes simplex virus 1 (HSV-1 or a Us3 deletion mutant thereof, or with bovine herpesvirus 1 (BoHV-1 by transmission and scanning electron microscopy, employing freezing technique protocols. Results:  The Golgi complex is a compact entity in a juxtanuclear position covered by a membrane on the cis face. Golgi membranes merge with membranes of the endoplasmic reticulum forming an entity with the perinuclear space. All compartments contained enveloped virions. After treatment with brefeldin A, HSV-1 virions aggregated in the perinuclear space and endoplasmic reticulum, while infectious progeny virus was still produced. Conclusions: The data suggest that virions derived by budding at nuclear membranes are intraluminally transported from the perinuclear space via Golgi -endoplasmic reticulum transitions into Golgi cisternae for packaging. Virions derived by budding at nuclear membranes are infective like Us3 deletion mutants, which  accumulate in the perinuclear space. Therefore, i de-envelopment followed by re-envelopment is not essential for production of infective progeny virus, ii the process taking place at the outer nuclear

3D Printing of Plant Golgi Stacks from Their Electron Tomographic Models.

Science.gov (United States)

Mai, Keith Ka Ki; Kang, Madison J; Kang, Byung-Ho

2017-01-01

Three-dimensional (3D) printing is an effective tool for preparing tangible 3D models from computer visualizations to assist in scientific research and education. With the recent popularization of 3D printing processes, it is now possible for individual laboratories to convert their scientific data into a physical form suitable for presentation or teaching purposes. Electron tomography is an electron microscopy method by which 3D structures of subcellular organelles or macromolecular complexes are determined at nanometer-level resolutions. Electron tomography analyses have revealed the convoluted membrane architectures of Golgi stacks, chloroplasts, and mitochondria. But the intricacy of their 3D organizations is difficult to grasp from tomographic models illustrated on computer screens. Despite the rapid development of 3D printing technologies, production of organelle models based on experimental data with 3D printing has rarely been documented. In this chapter, we present a simple guide to creating 3D prints of electron tomographic models of plant Golgi stacks using the two most accessible 3D printing technologies.

FAM21 directs SNX27–retromer cargoes to the plasma membrane by preventing transport to the Golgi apparatus

Science.gov (United States)

Lee, Seongju; Chang, Jaerak; Blackstone, Craig

2016-01-01

The endosomal network maintains cellular homeostasis by sorting, recycling and degrading endocytosed cargoes. Retromer organizes the endosomal sorting pathway in conjunction with various sorting nexin (SNX) proteins. The SNX27–retromer complex has recently been identified as a major endosomal hub that regulates endosome-to-plasma membrane recycling by preventing lysosomal entry of cargoes. Here, we show that SNX27 directly interacts with FAM21, which also binds retromer, within the Wiskott–Aldrich syndrome protein and SCAR homologue (WASH) complex. This interaction is required for the precise localization of SNX27 at an endosomal subdomain as well as for recycling of SNX27-retromer cargoes. Furthermore, FAM21 prevents cargo transport to the Golgi apparatus by controlling levels of phosphatidylinositol 4-phosphate, which facilitates cargo dissociation at the Golgi. Together, our results demonstrate that the SNX27–retromer–WASH complex directs cargoes to the plasma membrane by blocking their transport to lysosomes and the Golgi. PMID:26956659

The Golgi localized bifunctional UDP-rhamnose/UDP-galactose transporter family of Arabidopsis

DEFF Research Database (Denmark)

Rautengarten, Carsten; Ebert, Berit; Moreno, Ignacio

2014-01-01

Delivery of nucleotide sugar substrates into the Golgi apparatus and endoplasmic reticulum for processes such as cell wall biosynthesis and protein glycosylation is critical for plant growth and development. Plant genomes encode large families of uncharacterized nucleotide sugar transporters that...

Characterization of p28, a novel ERGIC/"cis"-Golgi protein, required for Golgi ribbon formation. pH measurements in the early secretory pathway "in vivo"

OpenAIRE

Kögler, Eva Jutta

2008-01-01

The secretory pathway of mammalian cells consists of several compartments. Transport between these organelles is accomplished via vesicular carriers or maturation. For non abundant proteins it is thought that transport receptors help the proteins to exit the ER in an effective way. The best characterized mammalian cargo receptor is ERGIC-53, which transports blood coagulation factor V and VIII, cathespin C and Z as well as alpha1-antitrypsin. It localizes to the ER Golgi intermediate compartm...

Selectivity of neuronal [3H]GABA accumulation in the visual cortex as revealed by Golgi staining of the labeled neurons

International Nuclear Information System (INIS)

Somogyi, P.; Freund, T.F.; Kisvarday, Z.F.; Halasz, N.

1981-01-01

[ 3 H]GABA was injected into the visual cortex of rats in vivo. The labeled amino acid was demonstrated by autoradiography using semithin sections of Golgi material. Selective accumulation was seen in the perikarya of Golgi-stained, gold-toned, aspinous stellate neurons. Spine-laden pyramidal-like cells did not show labeling. This method gives direct information about the dendritic arborization of a neuron, and its putative transmitter, and allows the identification of its synaptic connections. (Auth.)

Shifted Golgi targeting of glycosyltransferases and α-mannosidase IA from giantin to GM130-GRASP65 results in formation of high mannose N-glycans in aggressive prostate cancer cells.

Science.gov (United States)

Bhat, Ganapati; Hothpet, Vishwanath-Reddy; Lin, Ming-Fong; Cheng, Pi-Wan

2017-11-01

There is a pressing need for biomarkers that can distinguish indolent from aggressive prostate cancer to prevent over-treatment of patients with indolent tumor. Golgi targeting of glycosyltransferases was characterized by confocal microscopy after knockdown of GM130, giantin, or both. N-glycans on a trans-Golgi enzyme β4galactosyltransferase-1 isolated by immunoprecipitation from androgen-sensitive and independent prostate cancer cells were determined by matrix-assisted laser desorption-time of flight-mass spectrometry. In situ proximity ligation assay was employed to determine co-localization of (a) α-mannosidase IA, an enzyme required for processing Man 8 GlcNAc 2 down to Man 5 GlcNAc 2 to enable synthesis of complex-type N-glycans, with giantin, GM130, and GRASP65, and (b) trans-Golgi glycosyltransferases with high mannose N-glycans terminated with α3-mannose. Defective giantin in androgen-independent prostate cancer cells results in a shift of Golgi targeting of glycosyltransferases and α-mannosidase IA from giantin to GM130-GRASP65. Consequently, trans-Golgi enzymes and cell surface glycoproteins acquire high mannose N-glycans, which are absent in cells with functional giantin. In situ proximity ligation assays of co-localization of α-mannosidase IA with GM130 and GRASP65, and trans-Golgi glycosyltransferases with high mannose N-glycans are negative in androgen-sensitive LNCaP C-33 cells but positive in androgen-independent LNCaP C-81 and DU145 cells, and LNCaP C-33 cells devoid of giantin. In situ proximity ligation assays of Golgi localization of α-mannosidase IA at giantin versus GM130-GRASP65 site, and absence or presence of N-glycans terminated with α3-mannose on trans-Golgi glycosyltransferases may be useful for distinguishing indolent from aggressive prostate cancer cells. Copyright © 2017 Elsevier B.V. All rights reserved.

STED Imaging of Golgi Dynamics with Cer-SiR: A Two-Component, Photostable, High-Density Lipid Probe for Live Cells.

Science.gov (United States)

Erdmann, Roman S; Toomre, Derek; Schepartz, Alanna

2017-01-01

Long time-lapse super-resolution imaging in live cells requires a labeling strategy that combines a bright, photostable fluorophore with a high-density localization probe. Lipids are ideal high-density localization probes, as they are >100 times more abundant than most membrane-bound proteins and simultaneously demark the boundaries of cellular organelles. Here, we describe Cer-SiR, a two-component, high-density lipid probe that is exceptionally photostable. Cer-SiR is generated in cells via a bioorthogonal reaction of two components: a ceramide lipid tagged with trans-cyclooctene (Cer-TCO) and a reactive, photostable Si-rhodamine dye (SiR-Tz). These components assemble within the Golgi apparatus of live cells to form Cer-SiR. Cer-SiR is benign to cellular function, localizes within the Golgi at a high density, and is sufficiently photostable to enable visualization of Golgi structure and dynamics by 3D confocal or long time-lapse STED microscopy.

FMNL2 and -3 regulate Golgi architecture and anterograde transport downstream of Cdc42

DEFF Research Database (Denmark)

Kage, Frieda; Steffen, Anika; Ellinger, Adolf

2017-01-01

The Rho-family small GTPase Cdc42 localizes at plasma membrane and Golgi complex and aside from protrusion and migration operates in vesicle trafficking, endo- and exocytosis as well as establishment and/or maintenance of cell polarity. The formin family members FMNL2 and -3 are actin assembly fa...

Functional genomics indicates yeast requires Golgi/ER transport, chromatin remodeling, and DNA repair for low dose DMSO tolerance

Directory of Open Access Journals (Sweden)

Brandon David Gaytán

2013-08-01

Full Text Available Dimethyl sulfoxide (DMSO is frequently utilized as a solvent in toxicological and pharmaceutical investigations. It is therefore important to establish the cellular and molecular targets of DMSO in order to differentiate its intrinsic effects from those elicited by a compound of interest. We performed a genome-wide functional screen in Saccharomyces cerevisiae to identify deletion mutants exhibiting sensitivity to 1% DMSO, a concentration standard to yeast chemical profiling studies. We report that mutants defective in Golgi/ER transport are sensitive to DMSO, including those lacking components of the conserved oligomeric Golgi (COG complex. Moreover, strains deleted for members of the SWR1 histone exchange complex are hypersensitive to DMSO, with additional chromatin remodeling mutants displaying a range of growth defects. We also identify DNA repair genes important for DMSO tolerance. Finally, we demonstrate that overexpression of histone H2A.Z, which replaces chromatin-associated histone H2A in a SWR1-catalyzed reaction, confers resistance to DMSO. Many yeast genes described in this study have homologs in more complex organisms, and the data provided is applicable to future investigations into the cellular and molecular mechanisms of DMSO toxicity.

Retromer guides STxB and CD8-M6PR from early to recycling endosomes, EHD1 guides STxB from recycling endosome to Golgi

Science.gov (United States)

McKenzie, Jenna E.; Raisley, Brent; Zhou, Xin; Naslavsky, Naava; Taguchi, Tomohiko; Caplan, Steve; Sheff, David

2012-01-01

Retrograde trafficking transports proteins, lipids and toxins from the plasma membrane to the Golgi and ER. To reach the Golgi, these cargos must transit the endosomal system, consisting of early endosomes, recycling endosomes, late endosomes and lysosomes. All cargos pass through early endosomes, but may take different routes to the Golgi. Retromer dependent cargos bypass the late endosomes to reach the Golgi. We compared how two very different retromer dependent cargos negotiate the endosomal sorting system. Shiga toxin B, bound to the external layer of the plasma membrane, and chimeric CD8-Mannose-6-Phosphate Receptor, which is anchored via a transmembrane domain. Both appear to pass through the recycling endosome. Ablation of the recycling endosome diverted both of these cargos to an aberrant compartment and prevented them from reaching the Golgi. Once in the recycling endosome, Shiga toxin required EHD1 to traffic to the TGN, while the CD8-Mannose-6-Phosphate Receptor was not significantly dependent on EHD1. Knockdown of retromer components left cargo in the early endosomes, suggesting that it is required for retrograde exit from this compartment. This work establishes the recycling endosome as a required step in retrograde traffic of at least these two retromer dependent cargos. Along this pathway, retromer is associated with EE to recycling endosome traffic, while EHD1 is associated with recycling endosome to TGN traffic of STxB. PMID:22540229

The organization of the Golgi complex and microtubules in skeletal muscle is fiber type-dependent

DEFF Research Database (Denmark)

Ralston, E; Lu, Z; Ploug, Thorkil

1999-01-01

Skeletal muscle has a nonconventional Golgi complex (GC), the organization of which has been a subject of controversy in the past. We have now examined the distribution of the GC by immunofluorescence and immunogold electron microscopy in whole fibers from different rat muscles, both innervated a...

Plasma Membrane Targeting of Protocadherin 15 Is Regulated by the Golgi-Associated Chaperone Protein PIST

Directory of Open Access Journals (Sweden)

Hongyun Nie

2016-01-01

Full Text Available Protocadherin 15 (PCDH15 is a core component of hair cell tip-links and crucial for proper function of inner ear hair cells. Mutations of PCDH15 gene cause syndromic and nonsyndromic hearing loss. At present, the regulatory mechanisms responsible for the intracellular transportation of PCDH15 largely remain unknown. Here we show that PIST, a Golgi-associated, PDZ domain-containing protein, interacts with PCDH15. The interaction is mediated by the PDZ domain of PIST and the C-terminal PDZ domain-binding interface (PBI of PCDH15. Through this interaction, PIST retains PCDH15 in the trans-Golgi network (TGN and reduces the membrane expression of PCDH15. We have previously showed that PIST regulates the membrane expression of another tip-link component, cadherin 23 (CDH23. Taken together, our finding suggests that PIST regulates the intracellular trafficking and membrane targeting of the tip-link proteins CDH23 and PCDH15.

Force estimation from ensembles of Golgi tendon organs

Science.gov (United States)

Mileusnic, M. P.; Loeb, G. E.

2009-06-01

Golgi tendon organs (GTOs) located in the skeletal muscles provide the central nervous system with information about muscle tension. The ensemble firing of all GTO receptors in the muscle has been hypothesized to represent a reliable measure of the whole muscle force but the precision and accuracy of that information are largely unknown because it is impossible to record activity simultaneously from all GTOs in a muscle. In this study, we combined a new mathematical model of force sampling and transduction in individual GTOs with various models of motor unit (MU) organization and recruitment simulating various normal, pathological and neural prosthetic conditions. Our study suggests that in the intact muscle the ensemble GTO activity accurately encodes force information according to a nonlinear, monotonic relationship that has its steepest slope for low force levels and tends to saturate at the highest force levels. The relationship between the aggregate GTO activity and whole muscle tension under some pathological conditions is similar to one seen in the intact muscle during rapidly modulated, phasic excitation of the motor pool (typical for many natural movements) but quite different when the muscle is activated slowly or held at a given force level. Substantial deviations were also observed during simulated functional electrical stimulation.

Genetic, structural, and chemical insights into the dual function of GRASP55 in germ cell Golgi remodeling and JAM-C polarized localization during spermatogenesis.

Directory of Open Access Journals (Sweden)

Amandine Cartier-Michaud

2017-06-01

Full Text Available Spermatogenesis is a dynamic process that is regulated by adhesive interactions between germ and Sertoli cells. Germ cells express the Junctional Adhesion Molecule-C (JAM-C, encoded by Jam3, which localizes to germ/Sertoli cell contacts. JAM-C is involved in germ cell polarity and acrosome formation. Using a proteomic approach, we demonstrated that JAM-C interacted with the Golgi reassembly stacking protein of 55 kDa (GRASP55, encoded by Gorasp2 in developing germ cells. Generation and study of Gorasp2-/- mice revealed that knock-out mice suffered from spermatogenesis defects. Acrosome formation and polarized localization of JAM-C in spermatids were altered in Gorasp2-/- mice. In addition, Golgi morphology of spermatocytes was disturbed in Gorasp2-/- mice. Crystal structures of GRASP55 in complex with JAM-C or JAM-B revealed that GRASP55 interacted via PDZ-mediated interactions with JAMs and induced a conformational change in GRASP55 with respect of its free conformation. An in silico pharmacophore approach identified a chemical compound called Graspin that inhibited PDZ-mediated interactions of GRASP55 with JAMs. Treatment of mice with Graspin hampered the polarized localization of JAM-C in spermatids, induced the premature release of spermatids and affected the Golgi morphology of meiotic spermatocytes.

A golgi study of the optic tectum of the tegu lizard, Tupinambis nigropunctatus.

Science.gov (United States)

Butler, A B; Ebbesson, O E

1975-06-01

The dendritic patterns of cells in the optic tectum of the tegu lizard, Tupinambis nigropunctatus, were analyzed with the Ramon-Moliner modification of the Golgi-Cox technique. Cell types were compared with those described by other authors in the tectum of other reptiles; particular comparisons of our results were made with the description of cell types in the chameleon (Ramń, 1896), as the latter is the most complete analysis in the literature. The periventricular gray layers 3 and 5 consist primarily of two cell types--piriform or pyramidal shaped cells and horizontal cells. Cells in the medial portion of the tectum, in an area coextensive with the bilateral spinal projection zone, possess dendrites that extend across the midline. The latter cells have either fusiform or pyramidal shaped somas. The central white zone, layer 6, contains fibers, large fusiform or pyramidal shaped cells, fusiform cells, and small horizontal cells. The central gray zone, layer 7, is composed predominately of fusiform cells which have dendrites extending to the superficial optic layers, large polygonal cells, and horizontal cells. The superficial gray and white layers, layers 8-13, contain polygonal, fusiform, stellate, and horizontal elements. Layer 14 is composed solely of afferent optic tract fibers. Several differences in the occurrence and distribution of cell types between the tegu and the other reptiles studied are noted. Additionally, the laminar distribution of retinal, tectotectal, telencephalic, and spinal projections in the tegutectum can be related to the distribution of cell types, and those cells which may be postsynaptic to specific inputs can be identified. The highly differentiated laminar structure of the reptilian optic tectum, both in regard to cell type and to afferent and efferent connections, may serve as a model for studying some functional properties of lamination common to cortical structures.

Role of the Conserved Ologomeric Golgi Complex in the Abnormalities of Glycoprotein Processing in Breast Cancer Cells

National Research Council Canada - National Science Library

Zolov, Sergey

2004-01-01

.... We propose that the COG3 protein plays one of the main roles in these processes. We utilized RNA interference assay to knockdown COG3p in HeLa cells to determine the effect of its depletion on Golgi proteins localization...

Ramón y Cajal erroneously identified as Camillo Golgi on a souvenir postage stamp.

Science.gov (United States)

Triarhou, Lazaros C; del Cerro, Manuel

2012-01-01

Focusing on a philatelic oddity that erringly identifies a picture of Santiago Ramón y Cajal as that of Camillo Golgi, this brief article examines official and unofficial stamp issues honoring the two great neuroanatomists, one from Spain and the other from Italy, who were early Nobel Prize winners in Physiology or Medicine.

Identification and functional analysis of two Golgi-localized UDP-galactofuranose transporters with overlapping functions in Aspergillus niger.

Science.gov (United States)

Park, Joohae; Tefsen, Boris; Heemskerk, Marc J; Lagendijk, Ellen L; van den Hondel, Cees A M J J; van Die, Irma; Ram, Arthur F J

2015-11-02

Galactofuranose (Galf)-containing glycoconjugates are present in numerous microbes, including filamentous fungi where they are important for morphology, virulence and maintaining cell wall integrity. The incorporation of Galf-residues into galactomannan, galactomannoproteins and glycolipids is carried out by Golgi-localized Galf transferases. The nucleotide sugar donor used by these transferases (UDP-Galf) is produced in the cytoplasm and has to be transported to the lumen of the Golgi by a dedicated nucleotide sugar transporter. Based on homology with recently identified UDP-Galf-transporters in A. fumigatus and A. nidulans, two putative UDP-Galf-transporters in A. niger were found. Their function and localization was determined by gene deletions and GFP-tagging studies, respectively. The two putative UDP-Galf-transporters in A. niger are homologous to each other and are predicted to contain eleven transmembrane domains (UgtA) or ten transmembrane domains (UgtB) due to a reduced length of the C-terminal part of the UgtB protein. The presence of two putative UDP-Galf-transporters in the genome was not unique for A. niger. From the twenty Aspergillus species analysed, nine species contained two additional putative UDP-Galf-transporters. Three of the nine species were outside the Aspergillus section nigri, indication an early duplication of UDP-Galf-transporters and subsequent loss of the UgtB copy in several aspergilli. Deletion analysis of the single and double mutants in A. niger indicated that the two putative UDP-Galf-transporters (named UgtA and UgtB) have a redundant function in UDP-Galf-transport as only the double mutant displayed a Galf-negative phenotype. The Galf-negative phenotype of the double mutant could be complemented by expressing either CFP-UgtA or CFP-UgtB fusion proteins from their endogenous promoters, indicating that both CFP-tagged proteins are functional. Both Ugt proteins co-localize with each other as well as with the GDP

Phospho-eNOS Ser-1176 is associated with the nucleoli and the Golgi complex in C6 rat glioma cells.

Science.gov (United States)

Klinz, Franz-Josef; Herberg, Natalie; Arnhold, Stefan; Addicks, Klaus; Bloch, Wilhelm

2007-06-29

Enzymatic activity of endothelial nitric oxide synthase (eNOS) is controlled by posttranslational modifications, protein-protein interactions, and subcellular localization. For example, N-terminal fatty acid modifications target eNOS to the Golgi complex where it becomes phosphorylated. We show here by immunofluorescence analysis that phospho-eNOS Ser-1176 is enriched in the perinuclear region of interphase C6 rat glioma cells. Confocal double immunofluorescence microscopy with the Golgi marker protein 58K revealed that phospho-eNOS Ser-1176 is associated with the Golgi complex. Surprisingly, we observed several spots in the nucleus of C6 cells that were positive for phospho-eNOS Ser-1176. Confocal double immunofluorescence analysis with the nucleolus marker protein fibrillarin revealed that within the nucleus phospho-eNOS Ser-1176 is exclusively associated with the nucleoli. It is known that in mitotic cells nucleoli are lost during prophase and rebuild during telophase. In agreement with this, we find no nucleoli-like distribution of phospho-eNOS Ser-1176 in metaphase and anaphase C6 glioma cells. Our finding that phospho-eNOS Ser-1176 is selectively associated with the nucleoli points to a so far unknown role for eNOS in interphase glioma cells.

Endogenous glycosphingolipid acceptor specificity of sialosyltransferase systems in intact golgi membranes, synaptosomes, and synaptic plasma membranes from rat brain

International Nuclear Information System (INIS)

Durrie, R.; Saito, M.; Rosenberg, A.

1988-01-01

Preparations highly enriched in Golgi complex membranes, synaptosomes, and synaptic plasma membranes (SPM) by marker enzyme analysis and electron microscopic morphology were made from the brains of 28-day-old rats. These were incubated with cytidine 5'-monophosphate-N-acetyl[ 14 C]neuraminic acid (CMP-NeuAc) in a physiologic buffer, without detergents. Glycolipid sialosyltransferase activities (SATs) were measured by analyzing incorporation of radiolabeled NeuAc into endogenous membrane gangliosides. Golgi SAT was diversified in producing all the various molecular species of labeled gangliosides. Synaptosomal SAT exhibited a lower activity, but it was highly specific in its labeling pattern, with a marked preference for labeling NeuAcα2 → 8NeuAcα2 → 3Galβ1 → 4Glcβ1 → 1Cer (GD3 ganglioside). SPM prepared from the synaptosomes retained the GD3-related SAT (or SAT-2), and the total specific activity increased, which suggests that the location of the synaptosomal activity is in the SPM. These results indicate that SAT activity in Golgi membranes differs from that in synaptosomes with regard to endogenous acceptor substrate specificity and SAT activity of synaptosomes should be located in the synaptosomal plasma membrane. This SAT could function as an ectoenzyme in concert with ecto-sialidase to modulate the GD3 and other ganglioside population in situ at the SPM of the central nervous system

Golgi Study of Medium Spiny Neurons from Dorsolateral Striatum of the Turtle Trachemys scripta elegans.

Science.gov (United States)

González, Carolina; Mendoza, Janeth; Avila-Costa, María Rosa; Arias, Juan M; Barral, Jaime

2013-10-25

Comparative anatomy has shown similarities between reptilian and mammalian basal ganglia. Here the morphological characteristics of the medium spiny neurons (MSN) in the dorsolateral striatum (DLS) of the turtle are described after staining them with the Golgi technique. The soma of MSN in DLS showed three main forms: spherical, ovoid, and fusiform. The number of primary dendritic branches (3-4 dendrites/cell) was less than observed in mammals. The MSN axon originates mainly from the soma, and randomly it emerges at the beginning of the primary dendrite. The main differences between turtle and mammalian MSN were detected on dendritic spines. Short, thin, bifurcated and fungiform types of dendritic spines were observed in the turtle's MSN, according to their shape. In most of the analyzed spines, it was found that its length considerably exceeded that reported in mammals, with dendritic spines up to 8μm in length. These differences could play an important role in the modulation of motor networks preserved along the vertebrate evolution. Copyright © 2013. Published by Elsevier Ireland Ltd.

Mutations in TRAPPC12 Manifest in Progressive Childhood Encephalopathy and Golgi Dysfunction.

Science.gov (United States)

Milev, Miroslav P; Grout, Megan E; Saint-Dic, Djenann; Cheng, Yong-Han Hank; Glass, Ian A; Hale, Christopher J; Hanna, David S; Dorschner, Michael O; Prematilake, Keshika; Shaag, Avraham; Elpeleg, Orly; Sacher, Michael; Doherty, Dan; Edvardson, Simon

2017-08-03

Progressive childhood encephalopathy is an etiologically heterogeneous condition characterized by progressive central nervous system dysfunction in association with a broad range of morbidity and mortality. The causes of encephalopathy can be either non-genetic or genetic. Identifying the genetic causes and dissecting the underlying mechanisms are critical to understanding brain development and improving treatments. Here, we report that variants in TRAPPC12 result in progressive childhood encephalopathy. Three individuals from two unrelated families have either a homozygous deleterious variant (c.145delG [p.Glu49Argfs ∗ 14]) or compound-heterozygous variants (c.360dupC [p.Glu121Argfs ∗ 7] and c.1880C>T [p. Ala627Val]). The clinical phenotypes of the three individuals are strikingly similar: severe disability, microcephaly, hearing loss, spasticity, and characteristic brain imaging findings. Fibroblasts derived from all three individuals showed a fragmented Golgi that could be rescued by expression of wild-type TRAPPC12. Protein transport from the endoplasmic reticulum to and through the Golgi was delayed. TRAPPC12 is a member of the TRAPP protein complex, which functions in membrane trafficking. Variants in several other genes encoding members of the TRAPP complex have been associated with overlapping clinical presentations, indicating shared and distinct functions for each complex member. Detailed understanding of the TRAPP-opathies will illuminate the role of membrane protein transport in human disease. Copyright © 2017 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Golgi twins in late mitosis revealed by genetically encoded tags for live cell imaging and correlated electron microscopy

NARCIS (Netherlands)

Gaietta, Guido M; Giepmans, Ben N G; Deerinck, Thomas J; Smith, W Bryan; Ngan, Lucy; Llopis, Juan; Adams, Stephen R; Tsien, Roger Y; Ellisman, Mark H

2006-01-01

Combinations of molecular tags visible in light and electron microscopes become particularly advantageous in the analysis of dynamic cellular components like the Golgi apparatus. This organelle disassembles at the onset of mitosis and, after a sequence of poorly understood events, reassembles after

Study of monocyte membrane proteome perturbation during lipopolysaccharide-induced tolerance using iTRAQ-based quantitative proteomic approach

KAUST Repository

Zhang, Huoming

2010-07-02

Human monocytes\\' exposure to low-level lipopolysaccharide (LPS) induces temporary monocytic insensitivity to subsequent LPS challenge. The underlying mechanism of this phenomenon could have important clinical utilities in preventing and/or treating severe infections. In this study, we used an iTRAQ-based quantitative proteomic approach to comprehensively characterize the membrane proteomes of monocytes before and after LPS exposure. We identified a total of 1651 proteins, of which 53.6% were membrane proteins. Ninety-four percent of the proteins were quantified and 255 proteins were shown to be tightly regulated by LPS. Subcellular location analysis revealed organelle-specific response to LPS exposure: more than 90% of identified mitochondrial membrane proteins were significant downregulated, whereas the majority of proteins from other organelles such as ER, Golgi and ribosome were upregulated. Moreover, we found that the expression of most receptors potentially involved in LPS signal pathway (CD14, toll-like receptor 4, CD11/CD18 complex) were substantially decreased, while the expression of molecules involved in LPS neutralization were enhanced after LPS challenge. Together, these findings could be of significance in understanding the mechanism of LPS tolerance and provide values for designing new approaches for regulating monocytic responses in sepsis patients.

Study of monocyte membrane proteome perturbation during lipopolysaccharide-induced tolerance using iTRAQ-based quantitative proteomic approach

KAUST Repository

Zhang, Huoming; Zhao, Changqing; Li, Xin; Zhu, Yi; Gan, Chee Sian; Wang, Yong; Ravasi, Timothy; Qian, Pei-Yuan; Wong, Siew Cheng; Sze, Siu Kwan

2010-01-01

Human monocytes' exposure to low-level lipopolysaccharide (LPS) induces temporary monocytic insensitivity to subsequent LPS challenge. The underlying mechanism of this phenomenon could have important clinical utilities in preventing and/or treating severe infections. In this study, we used an iTRAQ-based quantitative proteomic approach to comprehensively characterize the membrane proteomes of monocytes before and after LPS exposure. We identified a total of 1651 proteins, of which 53.6% were membrane proteins. Ninety-four percent of the proteins were quantified and 255 proteins were shown to be tightly regulated by LPS. Subcellular location analysis revealed organelle-specific response to LPS exposure: more than 90% of identified mitochondrial membrane proteins were significant downregulated, whereas the majority of proteins from other organelles such as ER, Golgi and ribosome were upregulated. Moreover, we found that the expression of most receptors potentially involved in LPS signal pathway (CD14, toll-like receptor 4, CD11/CD18 complex) were substantially decreased, while the expression of molecules involved in LPS neutralization were enhanced after LPS challenge. Together, these findings could be of significance in understanding the mechanism of LPS tolerance and provide values for designing new approaches for regulating monocytic responses in sepsis patients.

Trafficking of human ADAM 12-L: retention in the trans-Golgi network

DEFF Research Database (Denmark)

Hougaard, S; Loechel, F; Xu, X

2000-01-01

We have investigated the trafficking of the membrane-anchored form of human ADAM 12 (ADAM 12-L) fused to a green fluorescence protein tag. Subcellular localization of the protein in transiently transfected cells was determined by fluorescence microscopy and trypsin sensitivity. Full-length ADAM 12...... the cytoplasmic and transmembrane domains, but not the Src homology 3 domain (SH3) binding sites. These results raise the possibility that a trafficking checkpoint in the trans-Golgi network is one of the cellular mechanisms for regulation of ADAM 12-L function, by allowing a rapid release of ADAM 12-L...

Different patterns of motor activity induce differential plastic changes in pyramidal neurons in the motor cortex of rats: A Golgi study.

Science.gov (United States)

Vázquez-Hernández, Nallely; González-Tapia, Diana C; Martínez-Torres, Nestor I; González-Tapia, David; González-Burgos, Ignacio

2017-09-14

Rehabilitation is a process which favors recovery after brain damage involving motor systems, and neural plasticity is the only real resource the brain has for inducing neurobiological events in order to bring about re-adaptation. Rats were placed on a treadmill and made to walk, in different groups, at different velocities and with varying degrees of inclination. Plastic changes in the spines of the apical and basal dendrites of fifth-layer pyramidal neurons in the motor cortices of the rats were detected after study with the Golgi method. Numbers of dendritic spines increased in the three experimental groups, and thin, mushroom, stubby, wide, and branched spines increased or decreased in proportion depending on the motor demands made of each group. Along with the numerical increase of spines, the present findings provide evidence that dendritic spines' geometrical plasticity is involved in the differential performance of motor activity. Copyright © 2017 Elsevier B.V. All rights reserved.

Function of the Golgi-located phosphate transporter PHT4;6 is critical for senescence-associated processes in Arabidopsis

Czech Academy of Sciences Publication Activity Database

Hassler, S.; Jung, B.; Lemke, L.; Novák, Ondřej; Strnad, Miroslav; Martinoia, E.; Neuhaus, H.E.

2016-01-01

Roč. 67, č. 15 (2016), s. 4671-4684 ISSN 0022-0957 R&D Projects: GA ČR GA15-22322S; GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : ammonium * cytokinin * golgi Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.830, year: 2016

Orf virus interferes with MHC class I surface expression by targeting vesicular transport and Golgi

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Rohde Jörg

2012-07-01

Full Text Available Abstract Background The Orf virus (ORFV, a zoonotic Parapoxvirus, causes pustular skin lesions in small ruminants (goat and sheep. Intriguingly, ORFV can repeatedly infect its host, despite the induction of a specific immunity. These immune modulating and immune evading properties are still unexplained. Results Here, we describe that ORFV infection of permissive cells impairs the intracellular transport of MHC class I molecules (MHC I as a result of structural disruption and fragmentation of the Golgi apparatus. Depending on the duration of infection, we observed a pronounced co-localization of MHC I and COP-I vesicular structures as well as a reduction of MHC I surface expression of up to 50%. These subversion processes are associated with early ORFV gene expression and are accompanied by disturbed carbohydrate trimming of post-ER MHC I. The MHC I population remaining on the cell surface shows an extended half-life, an effect that might be partially controlled also by late ORFV genes. Conclusions The presented data demonstrate that ORFV down-regulates MHC I surface expression in infected cells by targeting the late vesicular export machinery and the structure and function of the Golgi apparatus, which might aid to escape cellular immune recognition.

The trans-Golgi SNARE syntaxin 10 is required for optimal development of Chlamydia trachomatis

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Andrea L Lucas

2015-09-01

Full Text Available Chlamydia trachomatis, an obligate intracellular pathogen, grows inside of a vacuole, termed the inclusion. Within the inclusion, the organisms differentiate from the infectious elementary body (EB into the reticulate body (RB. The RB communicates with the host cell through the inclusion membrane to obtain the nutrients necessary to divide, thus expanding the chlamydial population. At late time points within the developmental cycle, the RBs respond to unknown molecular signals to redifferentiate into infectious EBs to perpetuate the infection cycle. One strategy for Chlamydia to obtain necessary nutrients and metabolites from the host is to intercept host vesicular trafficking pathways. In this study we demonstrate that a trans-Golgi soluble N-ethylmaleimide–sensitive factor attachment protein (SNARE, syntaxin 10, and/or syntaxin10-associated Golgi elements colocalize with the chlamydial inclusion. We hypothesized that Chlamydia utilizes the molecular machinery of syntaxin 10 at the inclusion membrane to intercept specific vesicular trafficking pathways in order to create and maintain an optimal intra-inclusion environment. To test this hypothesis, we used siRNA knockdown of syntaxin 10 to examine the impact of the loss of syntaxin 10 on chlamydial growth and development. Our results demonstrate that loss of syntaxin 10 leads to defects in normal chlamydial maturation including: variable inclusion size with fewer chlamydial organisms per inclusion, fewer infectious progeny, and delayed or halted RB-EB differentiation. These defects in chlamydial development correlate with an overabundance of NBD-lipid retained by inclusions cultured in syntaxin 10 knockdown cells. Overall, loss of syntaxin 10 at the inclusion membrane negatively affects Chlamydia. Understanding host machinery involved in maintaining an optimal inclusion environment to support chlamydial growth and development is critical towards understanding the molecular signals involved in

TMEM199 Deficiency Is a Disorder of Golgi Homeostasis Characterized by Elevated Aminotransferases, Alkaline Phosphatase, and Cholesterol and Abnormal Glycosylation

NARCIS (Netherlands)

Jansen, Jos C.; Timal, Sharita; van Scherpenzeel, Monique; Michelakakis, Helen; Vicogne, Dorothée; Ashikov, Angel; Moraitou, Marina; Hoischen, Alexander; Huijben, Karin; Steenbergen, Gerry; van den Boogert, Marjolein A. W.; Porta, Francesco; Calvo, Pier Luigi; Mavrikou, Mersyni; Cenacchi, Giovanna; van den Bogaart, Geert; Salomon, Jody; Holleboom, Adriaan G.; Rodenburg, Richard J.; Drenth, Joost P. H.; Huynen, Martijn A.; Wevers, Ron A.; Morava, Eva; Foulquier, François; Veltman, Joris A.; Lefeber, Dirk J.

2016-01-01

Congenital disorders of glycosylation (CDGs) form a genetically and clinically heterogeneous group of diseases with aberrant protein glycosylation as a hallmark. A subgroup of CDGs can be attributed to disturbed Golgi homeostasis. However, identification of pathogenic variants is seriously

Two endoplasmic reticulum (ER) membrane proteins that facilitate ER-to-Golgi transport of glycosylphosphatidylinositol-anchored proteins.

Science.gov (United States)

Barz, W P; Walter, P

1999-04-01

Many eukaryotic cell surface proteins are anchored in the lipid bilayer through glycosylphosphatidylinositol (GPI). GPI anchors are covalently attached in the endoplasmic reticulum (ER). The modified proteins are then transported through the secretory pathway to the cell surface. We have identified two genes in Saccharomyces cerevisiae, LAG1 and a novel gene termed DGT1 (for "delayed GPI-anchored protein transport"), encoding structurally related proteins with multiple membrane-spanning domains. Both proteins are localized to the ER, as demonstrated by immunofluorescence microscopy. Deletion of either gene caused no detectable phenotype, whereas lag1Delta dgt1Delta cells displayed growth defects and a significant delay in ER-to-Golgi transport of GPI-anchored proteins, suggesting that LAG1 and DGT1 encode functionally redundant or overlapping proteins. The rate of GPI anchor attachment was not affected, nor was the transport rate of several non-GPI-anchored proteins. Consistent with a role of Lag1p and Dgt1p in GPI-anchored protein transport, lag1Delta dgt1Delta cells deposit abnormal, multilayered cell walls. Both proteins have significant sequence similarity to TRAM, a mammalian membrane protein thought to be involved in protein translocation across the ER membrane. In vivo translocation studies, however, did not detect any defects in protein translocation in lag1Delta dgt1Delta cells, suggesting that neither yeast gene plays a role in this process. Instead, we propose that Lag1p and Dgt1p facilitate efficient ER-to-Golgi transport of GPI-anchored proteins.

ECA3, a Golgi-localized P_2A-type-ATPase, plays a crucial role in manganese nutrition in Arabidopsis

DEFF Research Database (Denmark)

Mills, Rebecca F.; Doherty, Melissa Louise; Lopez Marques, Rosa Laura

2008-01-01

and development, and transport processes play a key role in regulating their cellular levels. Arabidopsis (Arabidopsis thaliana) contains four P(2A)-type ATPase genes, AtECA1 to AtECA4, which are expressed in all major organs of Arabidopsis. To elucidate the physiological role of AtECA2 and AtECA3 in Arabidopsis...... not so striking because in this case all plants were severely affected. ECA3 partially restored the growth defect on high Mn of the yeast (Saccharomyces cerevisiae) pmr1 mutant, which is defective in a Golgi Ca/Mn pump (PMR1), and the yeast K616 mutant (Deltapmc1 Deltapmr1 Deltacnb1), defective in Golgi...

Structural Basis for the Interaction of the Golgi-Associated Retrograde Protein (GARP) Complex with the t-SNARE Syntaxin 6

Science.gov (United States)

Abascal-Palacios, Guillermo; Schindler, Christina; Rojas, Adriana L; Bonifacino, Juan S.; Hierro, Aitor

2016-01-01

Summary The Golgi-Associated Retrograde Protein (GARP) is a tethering complex involved in the fusion of endosome-derived transport vesicles to the trans-Golgi network through interaction with components of the Syntaxin 6/Syntaxin 16/Vti1a/VAMP4 SNARE complex. The mechanisms by which GARP and other tethering factors engage the SNARE fusion machinery are poorly understood. Herein we report the structural basis for the interaction of the human Ang2 subunit of GARP with Syntaxin 6 and the closely related Syntaxin 10. The crystal structure of Syntaxin 6 Habc domain in complex with a peptide from the N terminus of Ang2 shows a novel binding mode in which a di-tyrosine motif of Ang2 interacts with a highly conserved groove in Syntaxin 6. Structure-based mutational analyses validate the crystal structure and support the phylogenetic conservation of this interaction. The same binding determinants are found in other tethering proteins and syntaxins, suggesting a general interaction mechanism. PMID:23932592

Association of the golgi UDP-galactose transporter with UDP-galactose: ceramide galactosyltransferase allows UDP-galactose import in the endoplasmic reticulum

NARCIS (Netherlands)

Sprong, H.; Degroote, S.; Nilsson, T.; Kawakita, M.; Ishida, N.; van der Sluijs, P.; van Meer, G.

2003-01-01

UDP-galactose reaches the Golgi lumen through the UDP-galactose transporter (UGT) and is used for the galactosylation of proteins and lipids. Ceramides and diglycerides are galactosylated within the endoplasmic reticulum by the UDP-galactose: ceramide galactosyltransferase. It is not known how

Identification of rice cornichon as a possible cargo receptor for the Golgi-localized sodium transporter OsHKT1;3

Czech Academy of Sciences Publication Activity Database

Rosas-Santiago, P.; Lagunas-Goméz, D.; Barkla, B. J.; Vera-Estrella, R.; Lalonde, S.; Jones, A.; Frommer, W. B.; Zimmermannová, Olga; Sychrová, Hana; Pantoja, O.

2015-01-01

Roč. 66, č. 9 (2015), s. 2733-2748 ISSN 0022-0957 R&D Projects: GA MŠk(CZ) LD13037 Institutional support: RVO:67985823 Keywords : Cornichon * endoplasmic reticulum * Golgi * OsHKT1-3 * protein–protein interaction Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.677, year: 2015

GOLGA2/GM130, cis-Golgi Matrix Protein, is a Novel Target of Anticancer Gene Therapy

OpenAIRE

Chang, Seung-Hee; Hong, Seong-Ho; Jiang, Hu-Lin; Minai-Tehrani, Arash; Yu, Kyeong-Nam; Lee, Jae-Ho; Kim, Ji-Eun; Shin, Ji-Young; Kang, Bitna; Park, Sungjin; Han, Kiwon; Chae, Chanhee; Cho, Myung-Haing

2012-01-01

Achievement of long-term survival of patients with lung cancer treated with conventional chemotherapy is still difficult for treatment of metastatic and advanced tumors. Despite recent progress in investigational therapies, survival rates are still disappointingly low and novel adjuvant and systemic therapies are urgently needed. A recently elucidated secretory pathway is attracting considerable interest as a promising anticancer target. The cis-Golgi matrix protein, GOLGA2/GM130, plays an im...

Cell wall accumulation of fluorescent proteins derived from a trans-Golgi cisternal membrane marker and paramural bodies in interdigitated Arabidopsis leaf epidermal cells.

Science.gov (United States)

Akita, Kae; Kobayashi, Megumi; Sato, Mayuko; Kutsuna, Natsumaro; Ueda, Takashi; Toyooka, Kiminori; Nagata, Noriko; Hasezawa, Seiichiro; Higaki, Takumi

2017-01-01

In most dicotyledonous plants, leaf epidermal pavement cells develop jigsaw puzzle-like shapes during cell expansion. The rapid growth and complicated cell shape of pavement cells is suggested to be achieved by targeted exocytosis that is coordinated with cytoskeletal rearrangement to provide plasma membrane and/or cell wall materials for lobe development during their morphogenesis. Therefore, visualization of membrane trafficking in leaf pavement cells should contribute an understanding of the mechanism of plant cell morphogenesis. To reveal membrane trafficking in pavement cells, we observed monomeric red fluorescent protein-tagged rat sialyl transferases, which are markers of trans-Golgi cisternal membranes, in the leaf epidermis of Arabidopsis thaliana. Quantitative fluorescence imaging techniques and immunoelectron microscopic observations revealed that accumulation of the red fluorescent protein occurred mostly in the curved regions of pavement cell borders and guard cell ends during leaf expansion. Transmission electron microscopy observations revealed that apoplastic vesicular membrane structures called paramural bodies were more frequent beneath the curved cell wall regions of interdigitated pavement cells and guard cell ends in young leaf epidermis. In addition, pharmacological studies showed that perturbations in membrane trafficking resulted in simple cell shapes. These results suggested possible heterogeneity of the curved regions of plasma membranes, implying a relationship with pavement cell morphogenesis.

Phosphorylation in the C-terminal domain of Aquaporin-4 is required for Golgi transition in primary cultured astrocytes

International Nuclear Information System (INIS)

Kadohira, Ikuko; Abe, Yoichiro; Nuriya, Mutsuo; Sano, Kazumi; Tsuji, Shoji; Arimitsu, Takeshi; Yoshimura, Yasunori; Yasui, Masato

2008-01-01

Aquaporin-4 (AQP4) is expressed in the perivascular and subpial astrocytes end-feet in mammalian brain, and plays a critical component of an integrated water and potassium homeostasis. Here we examine whether AQP4 is phosphorylated in primary cultured mouse astrocytes. Astrocytes were metabolically labeled with [ 32 P]phosphoric acid, then AQP4 was immunoprecipitated with anti-AQP4 antibody. We observed that AQP4 was constitutively phosphorylated, which is reduced by treatment with protein kinase CK2 inhibitors. To elucidate the phosphorylation of AQP4 by CK2, myc-tagged wild-type or mutant AQP4 was transiently transfected in primary cultured astrocytes. Substitution of Ala residues for four putative CK2 phosphorylation sites in the C terminus abolished the phosphorylation of AQP4. Immunofluorescent microscopy revealed that the quadruple mutant was localized in the Golgi apparatus. These observations indicate that the C-terminal domain of AQP4 is constitutively phosphorylated at least in part by protein kinase CK2 and it is required for Golgi transition.

A membrane-anchored E-type endo-1,4-beta-glucanase is localized on Golgi and plasma membranes of higher plants.

Science.gov (United States)

Brummell, D A; Catala, C; Lashbrook, C C; Bennett, A B

1997-04-29

Endo-1,4-beta-D-glucanases (EGases, EC 3.2.1.4) are enzymes produced in bacteria, fungi, and plants that hydrolyze polysaccharides possessing a 1,4-beta-D-glucan backbone. All previously identified plant EGases are E-type endoglucanases that possess signal sequences for endoplasmic reticulum entry and are secreted to the cell wall. Here we report the characterization of a novel E-type plant EGase (tomato Cel3) with a hydrophobic transmembrane domain and structure typical of type II integral membrane proteins. The predicted protein is composed of 617 amino acids and possesses seven potential sites for N-glycosylation. Cel3 mRNA accumulates in young vegetative tissues with highest abundance during periods of rapid cell expansion, but is not hormonally regulated. Antibodies raised to a recombinant Cel3 protein specifically recognized three proteins, with apparent molecular masses of 93, 88, and 53 kDa, in tomato root microsomal membranes separated by sucrose density centrifugation. The 53-kDa protein comigrated in the gradient with plasma membrane markers, the 88-kDa protein with Golgi membrane markers, and the 93-kDa protein with markers for both Golgi and plasma membranes. EGase enzyme activity was also found in regions of the density gradient corresponding to both Golgi and plasma membranes, suggesting that Cel3 EGase resides in both membrane systems, the sites of cell wall polymer biosynthesis. The in vivo function of Cel3 is not known, but the only other known membrane-anchored EGase is present in Agrobacterium tumefaciens where it is required for cellulose biosynthesis.

VvGONST-A and VvGONST-B are Golgi-localised GDP-sugar transporters in grapevine (Vitis vinifera L.).

Science.gov (United States)

Utz, Daniella; Handford, Michael

2015-02-01

Plant nucleotide-sugar transporters (NSTs) are responsible for the import of nucleotide-sugar substrates into the Golgi lumen, for subsequent use in glycosylation reactions. NSTs are specific for either GDP- or UDP-sugars, and almost all transporters studied to date have been isolated from Arabidopsis thaliana L. In order to determine the conservation of the import mechanism in other higher plant species, here we report the identification and characterisation of VvGONST-A and VvGONST-B from grapevine (Vitis vinifera L. cv. Thompson Seedless), which are the orthologues of the GDP-sugar transporters GONST3 and GONST4 in Arabidopsis. Both grapevine NSTs possess the molecular features characteristic of GDP-sugar transporters, including a GDP-binding domain (GXL/VNK) towards the C-terminal. VvGONST-A and VvGONST-B expression is highest at berry setting and decreases throughout berry development and ripening. Moreover, we show using green fluorescent protein (GFP) tagged versions and brefeldin A treatments, that both are localised in the Golgi apparatus. Additionally, in vitro transport assays after expression of both NSTs in tobacco leaves indicate that VvGONST-A and VvGONST-B are capable of transporting GDP-mannose and GDP-glucose, respectively, but not a range of other UDP- and GDP-sugars. The possible functions of these NSTs in glucomannan synthesis and/or glycosylation of sphingolipids are discussed. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Disturbed neuronal ER-Golgi sorting of unassembled glycine receptors suggests altered subcellular processing is a cause of human hyperekplexia.

Science.gov (United States)

Schaefer, Natascha; Kluck, Christoph J; Price, Kerry L; Meiselbach, Heike; Vornberger, Nadine; Schwarzinger, Stephan; Hartmann, Stephanie; Langlhofer, Georg; Schulz, Solveig; Schlegel, Nadja; Brockmann, Knut; Lynch, Bryan; Becker, Cord-Michael; Lummis, Sarah C R; Villmann, Carmen

2015-01-07

Recent studies on the pathogenic mechanisms of recessive hyperekplexia indicate disturbances in glycine receptor (GlyR) α1 biogenesis. Here, we examine the properties of a range of novel glycine receptor mutants identified in human hyperekplexia patients using expression in transfected cell lines and primary neurons. All of the novel mutants localized in the large extracellular domain of the GlyR α1 have reduced cell surface expression with a high proportion of receptors being retained in the ER, although there is forward trafficking of glycosylated subpopulations into the ER-Golgi intermediate compartment and cis-Golgi compartment. CD spectroscopy revealed that the mutant receptors have proportions of secondary structural elements similar to wild-type receptors. Two mutants in loop B (G160R, T162M) were functional, but none of those in loop D/β2-3 were. One nonfunctional truncated mutant (R316X) could be rescued by coexpression with the lacking C-terminal domain. We conclude that a proportion of GlyR α1 mutants can be transported to the plasma membrane but do not necessarily form functional ion channels. We suggest that loop D/β2-3 is an important determinant for GlyR trafficking and functionality, whereas alterations to loop B alter agonist potencies, indicating that residues here are critical elements in ligand binding. Copyright © 2015 the authors 0270-6474/15/350422-16$15.00/0.

Regulation of cytokine receptors by Golgi N-glycan processing and endocytosis.

Science.gov (United States)

Partridge, Emily A; Le Roy, Christine; Di Guglielmo, Gianni M; Pawling, Judy; Cheung, Pam; Granovsky, Maria; Nabi, Ivan R; Wrana, Jeffrey L; Dennis, James W

2004-10-01

The Golgi enzyme beta1,6 N-acetylglucosaminyltransferase V (Mgat5) is up-regulated in carcinomas and promotes the substitution of N-glycan with poly N-acetyllactosamine, the preferred ligand for galectin-3 (Gal-3). Here, we report that expression of Mgat5 sensitized mouse cells to multiple cytokines. Gal-3 cross-linked Mgat5-modified N-glycans on epidermal growth factor and transforming growth factor-beta receptors at the cell surface and delayed their removal by constitutive endocytosis. Mgat5 expression in mammary carcinoma was rate limiting for cytokine signaling and consequently for epithelial-mesenchymal transition, cell motility, and tumor metastasis. Mgat5 also promoted cytokine-mediated leukocyte signaling, phagocytosis, and extravasation in vivo. Thus, conditional regulation of N-glycan processing drives synchronous modification of cytokine receptors, which balances their surface retention against loss via endocytosis.

Regulation of traffic and organelle architecture of the ER-Golgi interface by signal transduction.

Science.gov (United States)

Tillmann, Kerstin D; Millarte, Valentina; Farhan, Hesso

2013-09-01

The components that control trafficking between organelles of the secretory pathway as well as their architecture were uncovered to a reasonable extent in the past decades. However, only recently did we begin to explore the regulation of the secretory pathway by cellular signaling. In the current review, we focus on trafficking between the endoplasmic reticulum and the Golgi apparatus. We highlight recent advances that have been made toward a better understanding of how the secretory pathway is regulated by signaling and discuss how this knowledge is important to obtain an integrative view of secretion in the context of other homeostatic processes such as growth and proliferation.

Developmental disturbance of rat cerebral cortex following prenatal low-dose gamma-irradiation: a quantitative study

International Nuclear Information System (INIS)

Fukui, Y.; Hoshino, K.; Hayasaka, I.; Inouye, M.; Kameyama, Y.

1991-01-01

Pregnant rats were exposed to a single whole-body gamma-irradiation on Day 15 of gestation at a dose of 0.27, 0.48, 1.00, or 1.46 Gy. They were allowed to give birth and the offspring were killed at 6 or 12 weeks of age for microscopic and electron microscopic examinations of the cerebrum. Their body weight, brain weight, cortical thickness, and numerical densities of whole cells and synapses in somatosensory cortex were examined. Growth of the dendritic arborization of layer V pyramidal cells was also examined quantitatively with Golgi-Cox specimens. A significant dose-related reduction in brain weight was found in all irradiated groups. Neither gross malformation nor abnormality of cortical architecture was observed in the groups exposed to 0.27 Gy. A significant change was found in thickness of cortex in the groups exposed to 0.48 Gy or more. Cell packing density increased significantly in the group exposed to 1.00 Gy. Significant reduction in the number of intersections of dendrites with the zonal boundaries were found in the groups exposed to 0.27 Gy or more. There was no difference in the numerical density of synapses in layer I between the control and irradiated groups. These results suggested that doses as low as 0.27 Gy could cause a morphologically discernible change in the mammalian cerebrum

Manganese modified CdTe/CdS quantum dots as an immunoassay biosensor for the detection of Golgi protein-73.

Science.gov (United States)

Liu, Wei; Zhang, Aixia; Xu, Guanhong; Wei, Fangdi; Yang, Jing; Hu, Qin

2016-01-05

In this paper, a new fluorescence bioassay for Golgi protein-73 (GP73), a promising marker for monitoring liver tumor, was developed by using anti-GP73 antibody (GP73 Ab) capped quantum dots (QDs) coupled with protein A/G agarose beads in an attempt to improve the analysis time, cost and operation. First, carboxylic-functionalized Mn modified CdTe/CdS QDs were synthesized and covalently conjugated with GP73 Ab, then protein A/G agarose beads were specifically combined with the QDs-conjugated Ab to form the QDs-Ab-beads conjugate, which could capture and separate GP73 from the sample through simple centrifugation. It was found that the fluorescence intensity of the above QDs-Ab-beads biosensor could be specifically quenched by GP73 added. A simple, rapid and specific quantitative method for GP73 protein was proposed using the as-prepared QDs-Ab-beads as a biosensor. Under the optimized conditions, the calibration curve of the proposed assay showed good linearity with a correlation coefficient of 0.9935 in the concentration range of 20-150 ng/mL of GP73 protein. The limit of detection (defined as 3σ/K) was 10 ng/mL. The method built exhibited a great potential in the clinic test of GP73. Copyright © 2015 Elsevier B.V. All rights reserved.

Quantitative analysis of basal dendritic tree of layer III pyramidal neurons in different areas of adult human frontal cortex.

Science.gov (United States)

Zeba, Martina; Jovanov-Milosević, Natasa; Petanjek, Zdravko

2008-01-01

Large long projecting (cortico-cortical) layer IIIc pyramidal neurons were recently disclosed to be in the basis of cognitive processing in primates. Therefore, we quantitatively examined the basal dendritic morphology of these neurons by using rapid Golgi and Golgi Cox impregnation methods among three distinct Brodmann areas (BA) of an adult human frontal cortex: the primary motor BA4 and the associative magnopyramidal BA9 from left hemisphere and the Broca's speech BA45 from both hemispheres. There was no statistically significant difference in basal dendritic length or complexity, as dendritic spine number or their density between analyzed BA's. In addition, we analyzed each of these BA's immunocytochemically for distribution of SMI-32, a marker of largest long distance projecting neurons. Within layer IIIc, the highest density of SMI-32 immunopositive pyramidal neurons was observed in associative BA9, while in primary BA4 they were sparse. Taken together, these data suggest that an increase in the complexity of cortico-cortical network within human frontal areas of different functional order may be principally based on the increase in density of large, SMI-32 immunopositive layer IIIc neurons, rather than by further increase in complexity of their dendritic tree and synaptic network.

Active Dendrites and Differential Distribution of Calcium Channels Enable Functional Compartmentalization of Golgi Cells.

Science.gov (United States)

Rudolph, Stephanie; Hull, Court; Regehr, Wade G

2015-11-25

Interneurons are essential to controlling excitability, timing, and synaptic integration in neuronal networks. Golgi cells (GoCs) serve these roles at the input layer of the cerebellar cortex by releasing GABA to inhibit granule cells (grcs). GoCs are excited by mossy fibers (MFs) and grcs and provide feedforward and feedback inhibition to grcs. Here we investigate two important aspects of GoC physiology: the properties of GoC dendrites and the role of calcium signaling in regulating GoC spontaneous activity. Although GoC dendrites are extensive, previous studies concluded they are devoid of voltage-gated ion channels. Hence, the current view holds that somatic voltage signals decay passively within GoC dendrites, and grc synapses onto distal dendrites are not amplified and are therefore ineffective at firing GoCs because of strong passive attenuation. Using whole-cell recording and calcium imaging in rat slices, we find that dendritic voltage-gated sodium channels allow somatic action potentials to activate voltage-gated calcium channels (VGCCs) along the entire dendritic length, with R-type and T-type VGCCs preferentially located distally. We show that R- and T-type VGCCs located in the dendrites can boost distal synaptic inputs and promote burst firing. Active dendrites are thus critical to the regulation of GoC activity, and consequently, to the processing of input to the cerebellar cortex. In contrast, we find that N-type channels are preferentially located near the soma, and control the frequency and pattern of spontaneous firing through their close association with calcium-activated potassium (KCa) channels. Thus, VGCC types are differentially distributed and serve specialized functions within GoCs. Interneurons are essential to neural processing because they modulate excitability, timing, and synaptic integration within circuits. At the input layer of the cerebellar cortex, a single type of interneuron, the Golgi cell (GoC), carries these functions. The

Hepatitis C virus replication and Golgi function in brefeldin a-resistant hepatoma-derived cells.

Directory of Open Access Journals (Sweden)

Rayan Farhat

Full Text Available Recent reports indicate that the replication of hepatitis C virus (HCV depends on the GBF1-Arf1-COP-I pathway. We generated Huh-7-derived cell lines resistant to brefeldin A (BFA, which is an inhibitor of this pathway. The resistant cell lines could be sorted into two phenotypes regarding BFA-induced toxicity, inhibition of albumin secretion, and inhibition of HCV infection. Two cell lines were more than 100 times more resistant to BFA than the parental Huh-7 cells in these 3 assays. This resistant phenotype was correlated with the presence of a point mutation in the Sec7 domain of GBF1, which is known to impair the binding of BFA. Surprisingly, the morphology of the cis-Golgi of these cells remained sensitive to BFA at concentrations of the drug that allowed albumin secretion, indicating a dichotomy between the phenotypes of secretion and Golgi morphology. Cells of the second group were about 10 times more resistant than parental Huh-7 cells to the BFA-induced toxicity. The EC50 for albumin secretion was only 1.5-1.8 fold higher in these cells than in Huh-7 cells. However their level of secretion in the presence of inhibitory doses of BFA was 5 to 15 times higher. Despite this partially effective secretory pathway in the presence of BFA, the HCV infection was almost as sensitive to BFA as in Huh-7 cells. This suggests that the function of GBF1 in HCV replication does not simply reflect its role of regulator of the secretory pathway of the host cell. Thus, our results confirm the involvement of GBF1 in HCV replication, and suggest that GBF1 might fulfill another function, in addition to the regulation of the secretory pathway, during HCV replication.

The role of the active site Zn in the catalytic mechanism of the GH38 Golgi alpha-mannosidase II: Implications from noeuromycin inhibition

DEFF Research Database (Denmark)

Bols, Mikael; Kuntz, Douglas A.; Rose, David R.

2006-01-01

Golgi alpha-mannosidase II (GMII) is a Family 38 glycosyl hydrolase involved in the eukaryotic N-glycosylation pathway in protein synthesis. Understanding of its catalytic mechanism has been of interest for the development of specific inhibitors that could lead to novel anti-metastatic or anti-in...

Research advances in association between Golgi protein 73 and liver diseases

Directory of Open Access Journals (Sweden)

WEI Fengxian

2017-08-01

Full Text Available Golgi protein 73 (GP73 has a very low expression level in normal people, while it has a significantly higher expression level in patients with liver diseases and hepatocellular carcinoma (HCC, and therefore, it may become a new marker for HCC. This article introduces the distribution of GP73 in human body and definitions of different subtypes of GP73 and elaborates on its association with benign/malignant liver diseases and surgical operation based on the subtypes of GP73, as well as the application of GP73 in the differentiation of benign/malignant liver diseases. Since GP73 is closely associated with the development, progression, and prognosis of liver diseases, this article summarizes the latest advances in basic research, introduces the structural basis of fucosylated GP73 and proliferation, migration, and invasion of hepatoma cells and known signaling pathways, and lists the factors which affect the expression of GP73.

GOLGA2, Encoding A Master Regulator of Golgi Apparatus, Is Mutated in A Patient with A Neuromuscular Disorder

OpenAIRE

Shamseldin, Hanan E; Bennett, Alexis H; Alfadhel, Majid; Gupta, Vandana; Alkuraya, Fowzan S

2016-01-01

Golgi apparatus (GA) is a membrane-bound organelle that serves a multitude of critical cellular functions including protein secretion and sorting, and cellular polarity. Many Mendelian diseases are caused by mutations in genes encoding various components of GA. GOLGA2 encodes GM130, a necessary component for the assembly of GA as a single complex, and its deficiency has been found to result in severe cellular phenotypes. We describe the first human patient with a homozygous apparently loss of...

Influence of copper on the Golgi apparatus of the meristematic cells of the horse-bean - Vicia faba c. v. Povazsky

Energy Technology Data Exchange (ETDEWEB)

Kostal, L

1974-01-01

The influence of copper on the Golgi apparatus of beans was investigated. At 1 mg/l copper was toxic within 24 hours. After application of 1 mg/l Cu, a striking increase in the number of split vesicles was noted together with a significant decrease in the number of cisterns. The endoplasmic reticulum is often fragmented after application of Cu, showing separation of membrane.

Apoptosis-linked Gene-2 (ALG-2)/Sec31 Interactions Regulate Endoplasmic Reticulum (ER)-to-Golgi Transport

Science.gov (United States)

Helm, Jared R.; Bentley, Marvin; Thorsen, Kevin D.; Wang, Ting; Foltz, Lauren; Oorschot, Viola; Klumperman, Judith; Hay, Jesse C.

2014-01-01

Luminal calcium released from secretory organelles has been suggested to play a regulatory role in vesicle transport at several steps in the secretory pathway; however, its functional roles and effector pathways have not been elucidated. Here we demonstrate for the first time that specific luminal calcium depletion leads to a significant decrease in endoplasmic reticulum (ER)-to-Golgi transport rates in intact cells. Ultrastructural analysis revealed that luminal calcium depletion is accompanied by increased accumulation of intermediate compartment proteins in COPII buds and clusters of unfused COPII vesicles at ER exit sites. Furthermore, we present several lines of evidence suggesting that luminal calcium affected transport at least in part through calcium-dependent interactions between apoptosis-linked gene-2 (ALG-2) and the Sec31A proline-rich region: 1) targeted disruption of ALG-2/Sec31A interactions caused severe defects in ER-to-Golgi transport in intact cells; 2) effects of luminal calcium and ALG-2/Sec31A interactions on transport mutually required each other; and 3) Sec31A function in transport required luminal calcium. Morphological phenotypes of disrupted ALG-2/Sec31A interactions were characterized. We found that ALG-2/Sec31A interactions were not required for the localization of Sec31A to ER exit sites per se but appeared to acutely regulate the stability and trafficking of the cargo receptor p24 and the distribution of the vesicle tether protein p115. These results represent the first outline of a mechanism that connects luminal calcium to specific protein interactions regulating vesicle trafficking machinery. PMID:25006245

The regulation of ER export and Golgi retention of ST3Gal5 (GM3/GM4 synthase) and B4GalNAcT1 (GM2/GD2/GA2 synthase) by arginine/lysine-based motif adjacent to the transmembrane domain.

Science.gov (United States)

Uemura, Satoshi; Shishido, Fumi; Kashimura, Madoka; Inokuchi, Jin-ichi

2015-12-01

In the Golgi maturation model, the Golgi cisternae dynamically mature along a secretory pathway. In this dynamic process, glycosyltransferases are transported from the endoplasmic reticulum (ER) to the Golgi apparatus where they remain and function. The precise mechanism behind this maturation process remains unclear. We investigated two glycosyltransferases, ST3Gal5 (ST3G5) and B4GalNAcT1 (B4GN1), involved in ganglioside synthesis and examined their signal sequences for ER export and Golgi retention. Reports have suggested that the [R/K](X)[R/K] motif functions as an ER exporting signal; however, this signal sequence is insufficient in stably expressed, full-length ST3G5. Through further analysis, we have clarified that the (2)R(3)R(X)(5) (9)K(X)(3) (13)K sequence in ST3G5 is essential for ER export. We have named the sequence the R/K-based motif. On the other hand, for ER export of B4GN1, the homodimer formation in addition to the R/K-based motif is required for ER export suggesting the importance of unidentified lumenal side interaction. We found that ST3G5 R2A/R3A and K9A/K13A mutants localized not only in Golgi apparatus but also in endosomes. Furthermore, the amounts of mature type asparagine-linked (N)-glycans in ST3G5 R2A/R3A and K9A/K13A mutants were decreased compared with those in wild-type proteins, and the stability of the mutants was lower. These results suggest that the R/K-based motif is necessary for the Golgi retention of ST3G5 and that the retention is involved in the maturation of N-glycans and in stability. Thus, several basic amino acids located on the cytoplasmic tail of ST3G5 play important roles in both ER export and Golgi retention. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Enhanced SCAP glycosylation by inflammation induces macrophage foam cell formation.

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Chao Zhou

Full Text Available Inflammatory stress promotes foam cell formation by disrupting LDL receptor feedback regulation in macrophages. Sterol Regulatory Element Binding Proteins (SREBPs Cleavage-Activating Protein (SCAP glycosylation plays crucial roles in regulating LDL receptor and 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGCoAR feedback regulation. The present study was to investigate if inflammatory stress disrupts LDL receptor and HMGCoAR feedback regulation by affecting SCAP glycosylation in THP-1 macrophages. Intracellular cholesterol content was assessed by Oil Red O staining and quantitative assay. The expression of molecules controlling cholesterol homeostasis was examined using real-time quantitative RT-PCR and Western blotting. The translocation of SCAP from the endoplasmic reticulum (ER to the Golgi was detected by confocal microscopy. We demonstrated that exposure to inflammatory cytokines increased lipid accumulation in THP-1 macrophages, accompanying with an increased SCAP expression even in the presence of a high concentration of LDL. These inflammatory cytokines also prolonged the half-life of SCAP by enhancing glycosylation of SCAP due to the elevated expression of the Golgi mannosidase II. This may enhance translocation and recycling of SCAP between the ER and the Golgi, escorting more SREBP2 from the ER to the Golgi for activation by proteolytic cleavages as evidenced by an increased N-terminal of SREBP2 (active form. As a consequence, the LDL receptor and HMGCoAR expression were up-regulated. Interestingly, these effects could be blocked by inhibitors of Golgi mannosidases. Our results indicated that inflammation increased native LDL uptake and endogenous cholesterol de novo synthesis, thereby causing foam cell formation via increasing transcription and protein glycosylation of SCAP in macrophages. These data imply that inhibitors of Golgi processing enzymes might have a potential vascular-protective role in prevention of atherosclerotic foam

Prostaglandin E (dmPGE{sub 2}) action in vitro on the activity of rat liver Golgi apparatus galactosyltransferase

Energy Technology Data Exchange (ETDEWEB)

Kordowiak, A.M.; Tomecki, J.; Procyk, K.; Kapusta, P. [Uniwersytet Jagiellonski, Cracow (Poland)

1993-12-31

In vitro addition of 16,16`-dimethyl prostaglandin E{sub 2} to Golgi-rich membrane fraction in final concentration of 0.1 {mu}g/1 mg of protein increased generally the activity of galactosyltransferase in comparison with control. The percentage of phospholipids in the whole fraction was similar in both investigated groups, only the sum of phosphatidylenoamine + phosphatidic acid was significantly lower after addition of dmPGE{sub 2} than in the control (0.001 < P < 0.01). (author). 25 refs, 2 figs, 1 tab.

Cholesterol Regulates Syntaxin 6 Trafficking at trans-Golgi Network Endosomal Boundaries

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Meritxell Reverter

2014-05-01

Full Text Available Inhibition of cholesterol export from late endosomes causes cellular cholesterol imbalance, including cholesterol depletion in the trans-Golgi network (TGN. Here, using Chinese hamster ovary (CHO Niemann-Pick type C1 (NPC1 mutant cell lines and human NPC1 mutant fibroblasts, we show that altered cholesterol levels at the TGN/endosome boundaries trigger Syntaxin 6 (Stx6 accumulation into VAMP3, transferrin, and Rab11-positive recycling endosomes (REs. This increases Stx6/VAMP3 interaction and interferes with the recycling of αVβ3 and α5β1 integrins and cell migration, possibly in a Stx6-dependent manner. In NPC1 mutant cells, restoration of cholesterol levels in the TGN, but not inhibition of VAMP3, restores the steady-state localization of Stx6 in the TGN. Furthermore, elevation of RE cholesterol is associated with increased amounts of Stx6 in RE. Hence, the fine-tuning of cholesterol levels at the TGN-RE boundaries together with a subset of cholesterol-sensitive SNARE proteins may play a regulatory role in cell migration and invasion.

Golgi protein 73 as a biomarker for hepatocellular carcinoma: A diagnostic meta-analysis.

Science.gov (United States)

Yang, Jing; Li, Jingjing; Dai, Weiqi; Wang, Fan; Shen, Miao; Chen, Kan; Cheng, Ping; Zhang, Yan; Wang, Chengfen; Zhu, Rong; Zhang, Huawei; Zheng, Yuanyuan; Wang, Junshan; Xia, Yujing; Lu, Jie; Zhou, Yingqun; Guo, Chuanyong

2015-04-01

Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver and the third leading cause of cancer-related mortality worldwide. Conflicting results have been reported regarding the use of serum Golgi protein 73 (GP73) as a promising serum marker for the diagnosis of HCC; therefore, the aim of the present study was to provide a systematic review of the diagnostic performance of GP73 for HCC. Following a systematic review of the relevant studies, a number of indices associated with the accuracy of the diagnostic performance of GP73, including the sensitivity and specificity, were pooled using Meta Disc 1.4 software. Data were presented as forest plots, and summary receiver operating characteristic (SROC) curve analysis was used to summarize the overall test performance. Eleven studies were included in this meta-analysis. The summary estimates for serum GP73 in diagnosing HCC were as follows: Sensitivity, 77% [95% confidence interval (CI), 75-79%]; specificity, 91% (95% CI, 90-92%); positive likelihood ratio, 4.34 (95% CI, 2.19-8.59); negative likelihood ratio, 0.30 (95% CI, 0.26-0.36) and diagnostic odds ratio, 15.78 (95% CI, 6.95-35.83). The area under the SROC curve was 0.8638, and the Q index was 0.7944. Significant heterogeneity was found. This meta-analysis indicates a moderate diagnostic value of GP73 in HCC; however, further studies with rigorous design, large sample size and multiregional cooperation are required.

Tetrahymena gene encodes a protein that is homologous with the liver-specific F-antigen and associated with membranes of the Golgi apparatus and transport vesicles

DEFF Research Database (Denmark)

Hummel, R; Nørgaard, P; Andreasen, P H

1992-01-01

The F-antigen is a prominent liver protein which has been extensively used in studies on natural and induced immunological tolerance. However, its intracellular localization and biological function have remained elusive. It has generally been assumed that the F-antigen is confined phylogenetically...... of the Golgi apparatus and transport vesicles pointing to a role of TF-ag in membrane trafficking. Transcription of the TF-ag gene, as determined by run-on analyses, was only detectable in growing cells, and following transfer to starvation condition pre-existing TF-ag mRNA was rapidly degraded. The abundance...

Quantitative studies of antimicrobial peptide-lipid membrane interactions

DEFF Research Database (Denmark)

Kristensen, Kasper

antimicrobial peptides interact with phospholipid membranes. Motivated by that fact, the scope of this thesis is to study these antimicrobial peptide-lipid membrane interactions. In particular, we attempt to study these interactions with a quantitative approach. For that purpose, we consider the three...... a significant problem for quantitative studies of antimicrobial peptide-lipid membrane interactions; namely that antimicrobial peptides adsorb to surfaces of glass and plastic. Specifically, we demonstrate that under standard experimental conditions, this effect is significant for mastoparan X, melittin...... lead to inaccurate conclusions, or even completely wrong conclusions, when interpreting the FCS data. We show that, if all of the pitfalls are avoided, then FCS is a technique with a large potential for quantitative studies of antimicrobial peptide-induced leakage of fluorescent markers from large...

The Golgi-Localized γ-Ear-Containing ARF-Binding (GGA Proteins Alter Amyloid-β Precursor Protein (APP Processing through Interaction of Their GAE Domain with the Beta-Site APP Cleaving Enzyme 1 (BACE1.

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Bjoern von Einem

Full Text Available Proteolytic processing of amyloid-β precursor protein (APP by beta-site APP cleaving enzyme 1 (BACE1 is the initial step in the production of amyloid beta (Aβ, which accumulates in senile plaques in Alzheimer's disease (AD. Essential for this cleavage is the transport and sorting of both proteins through endosomal/Golgi compartments. Golgi-localized γ-ear-containing ARF-binding (GGA proteins have striking cargo-sorting functions in these pathways. Recently, GGA1 and GGA3 were shown to interact with BACE1, to be expressed in neurons, and to be decreased in AD brain, whereas little is known about GGA2. Since GGA1 impacts Aβ generation by confining APP to the Golgi and perinuclear compartments, we tested whether all GGAs modulate BACE1 and APP transport and processing. We observed decreased levels of secreted APP alpha (sAPPα, sAPPβ, and Aβ upon GGA overexpression, which could be reverted by knockdown. GGA-BACE1 co-immunoprecipitation was impaired upon GGA-GAE but not VHS domain deletion. Autoinhibition of the GGA1-VHS domain was irrelevant for BACE1 interaction. Our data suggest that all three GGAs affect APP processing via the GGA-GAE domain.

Asparagus IRX9, IRX10, and IRX14A Are Components of an Active Xylan Backbone Synthase Complex that Forms in the Golgi Apparatus.

Science.gov (United States)

Zeng, Wei; Lampugnani, Edwin R; Picard, Kelsey L; Song, Lili; Wu, Ai-Min; Farion, Isabela M; Zhao, Jia; Ford, Kris; Doblin, Monika S; Bacic, Antony

2016-05-01

Heteroxylans are abundant components of plant cell walls and provide important raw materials for the food, pharmaceutical, and biofuel industries. A number of studies in Arabidopsis (Arabidopsis thaliana) have suggested that the IRREGULAR XYLEM9 (IRX9), IRX10, and IRX14 proteins, as well as their homologs, are involved in xylan synthesis via a Golgi-localized complex termed the xylan synthase complex (XSC). However, both the biochemical and cell biological research lags the genetic and molecular evidence. In this study, we characterized garden asparagus (Asparagus officinalis) stem xylan biosynthesis genes (AoIRX9, AoIRX9L, AoIRX10, AoIRX14A, and AoIRX14B) by heterologous expression in Nicotiana benthamiana We reconstituted and partially purified an active XSC and showed that three proteins, AoIRX9, AoIRX10, and AoIRX14A, are necessary for xylan xylosyltranferase activity in planta. To better understand the XSC structure and its composition, we carried out coimmunoprecipitation and bimolecular fluorescence complementation analysis to show the molecular interactions between these three IRX proteins. Using a site-directed mutagenesis approach, we showed that the DxD motifs of AoIRX10 and AoIRX14A are crucial for the catalytic activity. These data provide, to our knowledge, the first lines of biochemical and cell biological evidence that AoIRX9, AoIRX10, and AoIRX14A are core components of a Golgi-localized XSC, each with distinct roles for effective heteroxylan biosynthesis. © 2016 American Society of Plant Biologists. All Rights Reserved.

3D Structure and Interaction of p24β and p24δ Golgi Dynamics Domains: Implication for p24 Complex Formation and Cargo Transport.

Science.gov (United States)

Nagae, Masamichi; Hirata, Tetsuya; Morita-Matsumoto, Kana; Theiler, Romina; Fujita, Morihisa; Kinoshita, Taroh; Yamaguchi, Yoshiki

2016-10-09

The p24 family consists of four subfamilies (p24α, p24β, p24γ, and p24δ), and the proteins are thought to form hetero-oligomeric complexes for efficient transport of cargo proteins from the endoplasmic reticulum to the Golgi apparatus. The proteins possess a conserved luminal Golgi dynamics (GOLD) domain, whose functions are largely unknown. Here, we present structural and biochemical studies of p24β1 and p24δ1 GOLD domains. Use of GOLD domain-deleted mutants revealed that the GOLD domain of p24δ1 is required for proper p24 hetero-oligomeric complex formation and efficient transport of GPI-anchored proteins. The p24β1 and p24δ1 GOLD domains share a common β-sandwich fold with a characteristic intrasheet disulfide bond. The GOLD domain of p24δ1 crystallized as dimers, allowing the analysis of a homophilic interaction site. Surface plasmon resonance and solution NMR analyses revealed that p24β1 and p24δ1 GOLD domains interact weakly (K d = ~10 -4 M). Bi-protein titration provided interaction site maps. We propose that the heterophilic interaction of p24 GOLD domains contributes to the formation of the p24 hetero-oligomeric complex and to efficient cargo transport. Copyright © 2016 Elsevier Ltd. All rights reserved.

HERMES docking/berthing system pilot study. Quantitative assessment

International Nuclear Information System (INIS)

Munoz Blasco, J.; Goicoechea Sanchez, F.J.

1993-01-01

This study falls within the framework of the incorporation of quantitative risk assessment to the activities planned for the ESA-HERMES project (ESA/ CNES). The main objective behind the study was the analysis and evaluation of the potential contribution of so-called probabilistic or quantitative safety analysis to the optimization of the safety development process for the systems carrying out the safety functions required by the new and complex HERMES Space Vehicle. For this purpose, a pilot study was considered a good start in quantitative safety assessments (QSA), as this approach has been frequently used in the past to establish a solid base in large-scale QSA application programs while avoiding considerable economic risks. It was finally decided to select the HERMES docking/berthing system with Man Tender Free Flyer as the case-study. This report describes the different steps followed in the study, along with the main insights obtained and the general conclusions drawn from the study results. (author)

The Drosophila Neurally Altered Carbohydrate Mutant Has a Defective Golgi GDP-fucose Transporter*

Science.gov (United States)

Geisler, Christoph; Kotu, Varshika; Sharrow, Mary; Rendić, Dubravko; Pöltl, Gerald; Tiemeyer, Michael; Wilson, Iain B. H.; Jarvis, Donald L.

2012-01-01

Studying genetic disorders in model organisms can provide insights into heritable human diseases. The Drosophila neurally altered carbohydrate (nac) mutant is deficient for neural expression of the HRP epitope, which consists of N-glycans with core α1,3-linked fucose residues. Here, we show that a conserved serine residue in the Golgi GDP-fucose transporter (GFR) is substituted by leucine in nac1 flies, which abolishes GDP-fucose transport in vivo and in vitro. This loss of function is due to a biochemical defect, not to destabilization or mistargeting of the mutant GFR protein. Mass spectrometry and HPLC analysis showed that nac1 mutants lack not only core α1,3-linked, but also core α1,6-linked fucose residues on their N-glycans. Thus, the nac1 Gfr mutation produces a previously unrecognized general defect in N-glycan core fucosylation. Transgenic expression of a wild-type Gfr gene restored the HRP epitope in neural tissues, directly demonstrating that the Gfr mutation is solely responsible for the neural HRP epitope deficiency in the nac1 mutant. These results validate the Drosophila nac1 mutant as a model for the human congenital disorder of glycosylation, CDG-IIc (also known as LAD-II), which is also the result of a GFR deficiency. PMID:22745127

Aberrant accumulation of the diabetes autoantigen GAD65 in Golgi membranes in conditions of ER stress and autoimmunity

DEFF Research Database (Denmark)

Phelps, Edward A; Cianciaruso, Chiara; Michael, Iacovos P

2016-01-01

Pancreatic islet beta cells are particularly susceptible to endoplasmic reticulum (ER) stress, which is implicated in beta cell dysfunction and loss during the pathogenesis of type 1 diabetes (T1D). The peripheral membrane protein GAD65 is an autoantigen in human T1D. GAD65 synthesizes GABA......, an important autocrine and paracrine signaling molecule and a survival factor in islets. We show that ER stress in primary beta cells perturbs the palmitoylation cycle controlling GAD65 endomembrane distribution, resulting in aberrant accumulation of the palmitoylated form in trans-Golgi membranes...... release from stressed and/or damaged beta cells, triggering autoimmunity....

Envisioning a Quantitative Studies Center: A Liberal Arts Perspective

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Gizem Karaali

2010-01-01

Full Text Available Several academic institutions are searching for ways to help students develop their quantitative reasoning abilities and become more adept at higher-level tasks that involve quantitative skills. In this note we study the particular way Pomona College has framed this issue within its own context and what it plans to do about it. To this end we describe our efforts as members of a campus-wide committee that was assigned the duty of investigating the feasibility of founding a quantitative studies center on our campus. These efforts involved analysis of data collected through a faculty questionnaire, discipline-specific input obtained from each departmental representative, and a survey of what some of our peer institutions are doing to tackle these issues. In our studies, we identified three critical needs where quantitative support would be most useful in our case: tutoring and mentoring for entry-level courses; support for various specialized and analytic software tools for upper-level courses; and a uniform basic training for student tutors and mentors. We surmise that our challenges can be mitigated effectively via the formation of a well-focused and -planned quantitative studies center. We believe our process, findings and final proposal will be helpful to others who are looking to resolve similar issues on their own campuses.

A traffic signal for heterodimeric amino acid transporters to transfer from the ER to the Golgi.

Science.gov (United States)

Ganapathy, Vadivel

2009-01-15

Heterodimeric amino acid transporters represent a unique class of transport systems that consist of a light chain that serves as the 'transporter proper' and a heavy chain that is necessary for targeting the complex to the plasma membrane. The currently prevailing paradigm assigns no role for the light chains in the cellular processing of these transporters. In this issue of the Biochemical Journal, Sakamoto et al. provide evidence contrary to this paradigm. Their studies with the rBAT -b(0,+)AT (related to b(0,+) amino acid transporter-b(0,+)-type amino acid transporter) heterodimeric amino acid transporter show that the C-terminus of the light chain b(0,+)AT contains a sequence motif that serves as the traffic signal for the transfer of the heterodimeric complex from the endoplasmic reticulum to the Golgi. This is a novel function for the light chain in addition to its already established role as the subunit responsible for the transport activity. These new findings also seem to be applicable to other heterodimeric amino acid transporters as well.

Asparagus IRX9, IRX10, and IRX14A Are Components of an Active Xylan Backbone Synthase Complex that Forms in the Golgi Apparatus1[OPEN

Science.gov (United States)

Zeng, Wei; Picard, Kelsey L.; Song, Lili; Wu, Ai-Min; Farion, Isabela M.; Zhao, Jia; Ford, Kris; Bacic, Antony

2016-01-01

Heteroxylans are abundant components of plant cell walls and provide important raw materials for the food, pharmaceutical, and biofuel industries. A number of studies in Arabidopsis (Arabidopsis thaliana) have suggested that the IRREGULAR XYLEM9 (IRX9), IRX10, and IRX14 proteins, as well as their homologs, are involved in xylan synthesis via a Golgi-localized complex termed the xylan synthase complex (XSC). However, both the biochemical and cell biological research lags the genetic and molecular evidence. In this study, we characterized garden asparagus (Asparagus officinalis) stem xylan biosynthesis genes (AoIRX9, AoIRX9L, AoIRX10, AoIRX14A, and AoIRX14B) by heterologous expression in Nicotiana benthamiana. We reconstituted and partially purified an active XSC and showed that three proteins, AoIRX9, AoIRX10, and AoIRX14A, are necessary for xylan xylosyltranferase activity in planta. To better understand the XSC structure and its composition, we carried out coimmunoprecipitation and bimolecular fluorescence complementation analysis to show the molecular interactions between these three IRX proteins. Using a site-directed mutagenesis approach, we showed that the DxD motifs of AoIRX10 and AoIRX14A are crucial for the catalytic activity. These data provide, to our knowledge, the first lines of biochemical and cell biological evidence that AoIRX9, AoIRX10, and AoIRX14A are core components of a Golgi-localized XSC, each with distinct roles for effective heteroxylan biosynthesis. PMID:26951434

Quantitative Preparation in Doctoral Education Programs: A Mixed-Methods Study of Doctoral Student Perspectives on their Quantitative Training

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Sarah L Ferguson

2017-07-01

Full Text Available Aim/Purpose: The purpose of the current study is to explore student perceptions of their own doctoral-level education and quantitative proficiency. Background: The challenges of preparing doctoral students in education have been discussed in the literature, but largely from the perspective of university faculty and program administrators. The current study directly explores the student voice on this issue. Methodology: Utilizing a sequential explanatory mixed-methods research design, the present study seeks to better understand doctoral-level education students’ perceptions of their quantitative methods training at a large public university in the southwestern United States. Findings: Results from both phases present the need for more application and consistency in doctoral-level quantitative courses. Additionally, there was a consistent theme of internal motivation in the responses, suggesting students perceive their quantitative training to be valuable beyond their personal interest in the topic. Recommendations for Practitioners: Quantitative methods instructors should emphasize practice in their quantitative courses and consider providing additional support for students through the inclusion of lab sections, tutoring, and/or differentiation. Pre-testing statistical ability at the start of a course is also suggested to better meet student needs. Impact on Society: The ultimate goal of quantitative methods in doctoral education is to produce high-quality educational researchers who are prepared to apply their knowledge to problems and research in education. Results of the present study can inform faculty and administrator decisions in doctoral education to best support this goal. Future Research: Using the student perspectives presented in the present study, future researchers should continue to explore effective instructional strategies and curriculum design within education doctoral programs. The inclusion of student voice can strengthen

Kidney-differentiated cells derived from Lowe Syndrome patient's iPSCs show ciliogenesis defects and Six2 retention at the Golgi complex.

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Wen-Chieh Hsieh

Full Text Available Lowe syndrome is an X-linked condition characterized by congenital cataracts, neurological abnormalities and kidney malfunction. This lethal disease is caused by mutations in the OCRL1 gene, which encodes for the phosphatidylinositol 5-phosphatase Ocrl1. While in the past decade we witnessed substantial progress in the identification and characterization of LS patient cellular phenotypes, many of these studies have been performed in knocked-down cell lines or patient's cells from accessible cell types such as skin fibroblasts, and not from the organs affected. This is partially due to the limited accessibility of patient cells from eyes, brain and kidneys. Here we report the preparation of induced pluripotent stem cells (iPSCs from patient skin fibroblasts and their reprogramming into kidney cells. These reprogrammed kidney cells displayed primary cilia assembly defects similar to those described previously in cell lines. Additionally, the transcription factor and cap mesenchyme marker Six2 was substantially retained in the Golgi complex and the functional nuclear-localized fraction was reduced. These results were confirmed using different batches of differentiated cells from different iPSC colonies and by the use of the human proximal tubule kidney cell line HK2. Indeed, OCRL1 KO led to both ciliogenesis defects and Six2 retention in the Golgi complex. In agreement with Six2's role in the suppression of ductal kidney lineages, cells from this pedigree were over-represented among patient kidney-reprogrammed cells. We speculate that this diminished efficacy to produce cap mesenchyme cells would cause LS patients to have difficulties in replenishing senescent or damaged cells derived from this lineage, particularly proximal tubule cells, leading to pathological scenarios such as tubular atrophy.

Alteraciones de la morfología dendrítica neuronal en la corteza cerebral de ratones infectados con rabia: un estudio con la técnica de Golgi

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Orlando Torres-Fernández

2007-12-01

Conclusiones. Estos resultados son evidencia de que el virus de la rabia sí puede inducir daño neuronal estructural. Además, esta infección aparentemente interfiere con los mecanismos de impregnación argéntica del método de Golgi.

The APOSTEL recommendations for reporting quantitative optical coherence tomography studies

DEFF Research Database (Denmark)

Cruz-Herranz, Andrés; Balk, Lisanne J; Oberwahrenbrock, Timm

2016-01-01

OBJECTIVE: To develop consensus recommendations for reporting of quantitative optical coherence tomography (OCT) study results. METHODS: A panel of experienced OCT researchers (including 11 neurologists, 2 ophthalmologists, and 2 neuroscientists) discussed requirements for performing and reporting...... quantitative analyses of retinal morphology and developed a list of initial recommendations based on experience and previous studies. The list of recommendations was subsequently revised during several meetings of the coordinating group. RESULTS: We provide a 9-point checklist encompassing aspects deemed...... relevant when reporting quantitative OCT studies. The areas covered are study protocol, acquisition device, acquisition settings, scanning protocol, funduscopic imaging, postacquisition data selection, postacquisition data analysis, recommended nomenclature, and statistical analysis. CONCLUSIONS...

Radioautographic study of the synthesis and migration of glycoproteins in the cells of the rat adrenal medulla

International Nuclear Information System (INIS)

Benchimol, Sarita; Cantin, Marc

1978-01-01

Rats were injected intravenously with ( 3 H) fucose to study the synthesis and migration of glycoproteins into adrenaline-storing and noradrenaline-storing cells of the adrenal medulla and to evaluate the fate of this radioactive sugar in both serum and adrenal-medulla at various time intervals. Radioactivity was decreased in serum by 50% between 5 and 20 min after the injection and by a hundred fold with 1 h. There was a sharp decrease in the radioactivity of the adrenal-medulla between 5 and 20 min after the injection and a slight, continuous decrease thereafter. The adrenal-medullae were fixed 5 min, 20 min, 1 h and 4 h after intravenous injection of [ 3 H] fucose, and radiautographs were analysed quantitatively after development in Microdol X. Kinetic analysis showed that, in both cell types, glycoprotein synthesis is completed in the Golgi complex and glycoproteins migrate subsequently to the secretory granules and to the cell coat. This analysis also revealed that [ 3 H] fucose moves much more rapidly in the Golgi complex of noradrenaline-storing cells than in that of adrenaline-storing cells and appears much earlier in the secretory granules of the former cell type [fr

Golgi protein 73 versus alpha-fetoprotein as a biomarker for hepatocellular carcinoma: a diagnostic meta- analysis

International Nuclear Information System (INIS)

Zhou, Ying; Yin, Xin; Ying, Jun; Zhang, BoHeng

2012-01-01

There have been conflicting reports about serum golgi protein 73 (GP73) as one of the most promising serum markers for the diagnosis of hepatocellular carcinoma (HCC). This study was to make a systematic review about the diagnostic accuracy of serum GP73 versus alpha-fetoprotein (AFP) for HCC. After a systematic review of related studies, sensitivity, specificity and other measures about the accuracy of serum GP73 and AFP in the diagnosis of HCC were pooled using random-effects models. Summary receiver operating characteristic curve analysis was used to summarize the overall test performance. Eight studies were included in our meta-analysis. The summary estimates for serum GP73 and AFP in diagnosing HCC in the studies included were as follows: sensitivity, 76% (95% confidence interval (CI) 51-91%) vs. 70% (47-86%); specificity, 86% (95%CI 65-95%) vs. 89% (69-96%); diagnostic odds ratio (DOR), 18.59 (95%CI 5.33-64.91) vs. 18.00(9.41-34.46); and area under sROC, 0.88 (95%CI 0.77-0.99) vs. 0.86 (95%CI 0.84-0.87). The current evidence indicates that serum GP73 has a comparable accuracy to AFP for the diagnosis of HCC, while the value of serum GP73 in combination with AFP for HCC detection deserves further investigation

Restoration of Compact Golgi Morphology in Advanced Prostate Cancer Enhances Susceptibility to Galectin-1-induced Apoptosis by Modifying Mucin O-glycan Synthesis

OpenAIRE

Petrosyan, Armen; Holzapfel, Melissa S.; Muirhead, David E.; Cheng, Pi-Wan

2014-01-01

Prostate cancer progression is associated with up-regulation of sialyl-T antigen produced by β-galactoside α-2,3-sialyltransferase-1 (ST3Gal1) but not with core 2-associated polylactosamine despite expression of core 2 N-acetylglucosaminyltransferase-L (C2GnT-L/GCNT1). This property allows androgen-refractory prostate cancer cells to evade galectin-1 (LGALS1)-induced apoptosis, but the mechanism is not known. We have recently reported that Golgi targeting of glycosyltransferases is mediated b...

Structures of human Golgi-resident glutaminyl cyclase and its complexes with inhibitors reveal a large loop movement upon inhibitor binding.

Science.gov (United States)

Huang, Kai-Fa; Liaw, Su-Sen; Huang, Wei-Lin; Chia, Cho-Yun; Lo, Yan-Chung; Chen, Yi-Ling; Wang, Andrew H-J

2011-04-08

Aberrant pyroglutamate formation at the N terminus of certain peptides and proteins, catalyzed by glutaminyl cyclases (QCs), is linked to some pathological conditions, such as Alzheimer disease. Recently, a glutaminyl cyclase (QC) inhibitor, PBD150, was shown to be able to reduce the deposition of pyroglutamate-modified amyloid-β peptides in brain of transgenic mouse models of Alzheimer disease, leading to a significant improvement of learning and memory in those transgenic animals. Here, we report the 1.05-1.40 Å resolution structures, solved by the sulfur single-wavelength anomalous dispersion phasing method, of the Golgi-luminal catalytic domain of the recently identified Golgi-resident QC (gQC) and its complex with PBD150. We also describe the high-resolution structures of secretory QC (sQC)-PBD150 complex and two other gQC-inhibitor complexes. gQC structure has a scaffold similar to that of sQC but with a relatively wider and negatively charged active site, suggesting a distinct substrate specificity from sQC. Upon binding to PBD150, a large loop movement in gQC allows the inhibitor to be tightly held in its active site primarily by hydrophobic interactions. Further comparisons of the inhibitor-bound structures revealed distinct interactions of the inhibitors with gQC and sQC, which are consistent with the results from our inhibitor assays reported here. Because gQC and sQC may play different biological roles in vivo, the different inhibitor binding modes allow the design of specific inhibitors toward gQC and sQC.

COPA mutations impair ER-Golgi transport causing hereditary autoimmune-mediated lung disease and arthritis

Science.gov (United States)

Watkin, Levi B.; Jessen, Birthe; Wiszniewski, Wojciech; Vece, Timothy; Jan, Max; Sha, Youbao; Thamsen, Maike; Santos-Cortez, Regie L. P.; Lee, Kwanghyuk; Gambin, Tomasz; Forbes, Lisa; Law, Christopher S.; Stray-Petersen, Asbjørg; Cheng, Mickie H.; Mace, Emily M.; Anderson, Mark S.; Liu, Dongfang; Tang, Ling Fung; Nicholas, Sarah K.; Nahmod, Karen; Makedonas, George; Canter, Debra; Kwok, Pui-Yan; Hicks, John; Jones, Kirk D.; Penney, Samantha; Jhangiani, Shalini N.; Rosenblum, Michael D.; Dell, Sharon D.; Waterfield, Michael R.; Papa, Feroz R.; Muzny, Donna M.; Zaitlen, Noah; Leal, Suzanne M.; Gonzaga-Jauregui, Claudia; Boerwinkle, Eric; Eissa, N. Tony; Gibbs, Richard A.; Lupski, James R.; Orange, Jordan S.; Shum, Anthony K.

2015-01-01

Advances in genomics have allowed unbiased genetic studies of human disease with unexpected insights into the molecular mechanisms of cellular immunity and autoimmunity1. We performed whole exome sequencing (WES) and targeted sequencing in patients with an apparent Mendelian syndrome of autoimmune disease characterized by high-titer autoantibodies, inflammatory arthritis and interstitial lung disease (ILD). In five families, we identified four unique deleterious variants in the Coatomer subunit alpha (COPA) gene all located within the same functional domain. We hypothesized that mutant COPA leads to a defect in intracellular transport mediated by coat protein complex I (COPI)2–4. We show that COPA variants impair binding of proteins targeted for retrograde Golgi to ER transport and demonstrate that expression of mutant COPA leads to ER stress and the upregulation of Th17 priming cytokines. Consistent with this pattern of cytokine expression, patients demonstrated a significant skewing of CD4+ T cells toward a T helper 17 (Th17) phenotype, an effector T cell population implicated in autoimmunity5,6. Our findings uncover an unexpected molecular link between a vesicular transport protein and a syndrome of autoimmunity manifested by lung and joint disease. These findings provide a unique opportunity to understand how alterations in cellular homeostasis caused by a defect in the intracellular trafficking pathway leads to the generation of human autoimmune disease. PMID:25894502

Cleavage of ST6Gal I by Radiation-Induced BACE1 Inhibits Golgi-Anchored ST6Gal I-Mediated Sialylation of Integrin β1 and Migration in Colon Cancer Cells

International Nuclear Information System (INIS)

Lee, Minyoung; Park, Jung-Jin; Ko, Young-Gyu; Lee, Yun-Sil

2012-01-01

Previously, we found that β-galactoside α2,6-sialyltransferase (ST6Gal I), an enzyme that adds sialic acids to N-linked oligosaccharides of glycoproteins and is frequently overexpressed in cancer cells, is up-regulated by ionizing radiation (IR) and cleaved to a form possessing catalytic activity comparable to that of the Golgi-localized enzyme. Moreover, this soluble form is secreted into the culture media. Induction of ST6Gal I significantly increased the migration of colon cancer cells via sialylation of integrin β1. Here, we further investigated the mechanisms underlying ST6Gal I cleavage, solubilization and release from cells, and addressed its functions, focusing primarily on cancer cell migration. We performed immunoblotting and lectin affinity assay to analyze the expression of ST6 Gal I and level of sialylated integrin β1. After ionizing radiation, migration of cells was measured by in vitro migration assay. α2, 6 sialylation level of cell surface was analyzed by flow cytometry. Cell culture media were concentrated and then analyzed for soluble ST6Gal I levels using an α2, 6 sialyltransferase sandwich ELISA. We found that ST6Gal I was cleaved by BACE1 (β-site amyloid precursor protein-cleaving enzyme), which was specifically overexpressed in response to IR. The soluble form of ST6Gal I, which also has sialyltransferase enzymatic activity, was cleaved from the Golgi membrane and then released into the culture media. Both non-cleaved and cleaved forms of ST6Gal I significantly increased colon cancer cell migration in a sialylation-dependent manner. The pro-migratory effect of the non-cleaved form of ST6Gal I was dependent on integrin β1 sialylation, whereas that of the cleaved form of ST6Gal I was not, suggesting that other intracellular sialylated molecules apart from cell surface molecules such as integrin β1 might be involved in mediating the pro-migratory effects of the soluble form of ST6Gal I. Moreover, production of soluble form ST6Gal I by

Ghrelin in the fetal pancreas - a digital quantitation study

DEFF Research Database (Denmark)

Hasselby, Jane Preuss; Maroun, Lisa Leth; Federspiel, Birgitte Hartnack

2012-01-01

Hasselby JP, Maroun LL, Federspiel BH, Vainer B. Ghrelin in the fetal pancreas - a digital quantitation study. APMIS 2011. Ghrelin is a hormone produced by specialized neuroendocrine cells located in the fetal pancreas. In the adult, ghrelin has multiple effects, but in the fetus the role...... of ghrelin and the distribution of ghrelin-producing cells is not well documented. The aim of this study was to describe and quantitate the number of ghrelin positive cells in the pancreas during gestation. The material consisted of pancreatic tissue from 19 fetuses at different gestational ages...

Serum Golgi protein 73 is a prognostic rather than diagnostic marker in hepatocellular carcinoma.

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Dong, Min; Chen, Zhan-Hong; Li, Xing; Li, Xiao-Yun; Wen, Jing-Yun; Lin, Qu; Ma, Xiao-Kun; Wei, Li; Chen, Jie; Ruan, Dan-Yun; Lin, Ze-Xiao; Wang, Tian-Tian; Wu, Dong-Hao; Wu, Xiang-Yuan

2017-11-01

Serum Golgi protein 73 (sGP73) is a candidate diagnostic biomarker for hepatocellular carcinoma (HCC). However, current evidence of its diagnostic value is conflicting, primarily due to the small sample sizes of previous studies, and its prognostic role in HCC also remains unclear. In the present study, sGP73 levels in 462 patients with HCC, 186 patients with liver cirrhosis, and 83 healthy controls were evaluated using ELISA, and it was identified that the median sGP73 levels were significantly higher in the HCC (18.7 ng/ml) and liver cirrhosis (18.5 ng/ml) patients than in the healthy controls (0 ng/ml; both P<0.001); however, the levels did not significantly differ between the HCC and liver cirrhosis groups (P=0.632). sGP73 had an inferior sensitivity and specificity for HCC diagnosis (27.79 and 77.96%, respectively) compared with α-fetoprotein (57.36 and 90.96%, respectively; P<0.001). In the HCC group, a high level of sGP73 was associated with aggressive clinicopathological features and independently predicted poor overall survival (OS) time (P<0.001). Additionally, in patients with resectable HCC, a high level of sGP73 was associated with significantly decreased disease-free survival (P<0.001) and OS (P=0.039) times compared with a low level of sGP73. This study demonstrated that sGP73 is unsuitable as a diagnostic marker for the early detection of HCC; however, it is an independent negative prognostic marker, providing a novel risk stratification factor and a potential therapeutic molecular target for HCC.

Hsp47 and cyclophilin B traverse the endoplasmic reticulum with procollagen into pre-Golgi intermediate vesicles. A role for Hsp47 and cyclophilin B in the export of procollagen from the endoplasmic reticulum.

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Smith, T; Ferreira, L R; Hebert, C; Norris, K; Sauk, J J

1995-08-04

Hsp47 and cyclophilin B (CyPB) are residents of the endoplasmic reticulum (ER). Both of these proteins are closely associated with polysome-associated alpha 1(I) procollagen chains. Hsp47 possesses chaperone properties early during the translation of procollagen while the cis/trans-isomerase properties of CyPB facilitate procollagen folding. In this report, we further investigate the interaction of these proteins with procollagen I during export from the ER. To inhibit vesicular budding and retain procollagen within the ER, cells were treated with the heterotrimeric G protein inhibitor mastoparan or calphostin C, a specific inhibitor of diacylglycerol/phorbol ester binding proteins. To arrest procollagen in pre-Golgi intermediate vesicles, cells were treated with guanosine 5'-3-O-(thio)triphosphate. Pulse-chase experiments of cells labeled with [35S]methionine followed by immunoprecipitation during the chase period with anti-procollagen, anti-Hsp47, and anti-CyPB antibodies were performed to reveal the relationship between Hsp47/CyPB/procollagen I. The distribution of procollagen, Hsp47, and CyPB to the ER and/or pre-Golgi vesicles was verified by immunofluorescence. Hsp47 and CyPB remained associated with procollagen retained within the ER. Hsp47 and CyPB were also associated with procollagen exported from the ER into pre-Golgi intermediate vesicles. Treatment of cells with cyclosporin A diminished the levels of CyPB bound to procollagen and diminished the rate of Hsp47 released from procollagen and the rate of procollagen secretion, suggesting that Hsp47 release from procollagen may be driven by helix formation. Also, these studies suggest that Hsp47 may resemble protein disulfide isomerase and possess both chaperone and anti-chaperone properties. During translation, high levels of Hsp47 are seen to limit protein aggregation and facilitate chain registration. Later, Hsp47 and/or CyPB and protein disulfide isomerase act as anti-chaperones and provide the basis for

Role of quantitative and dynamic radioactive studies in renal testing

International Nuclear Information System (INIS)

Raynaud, C.

1977-01-01

Many dynamic and quantitative radioactive tests are at present used in studying renal function. Whether involving dynamic morphological tests such as sequential images, dynamic quantitative tests such as the renogram or quantitative static tests such as radioactive clearances, their effective and original contribution is rather unimportant. Only one provides original data, the Hg renal uptake test but it is generally avoided due to the radiation dose absorbed by the kidney in children. A study of the causes of this lack of effectiveness leads to the observation that such tests are not well adapted to the needs of kidneys specialists. They are for the most part based on replacing a 'cold' indicator by radioactive indicator and the advantages anticipated from using radionuclide are not evident. In fact, they are often cancelled by the shortcomings of external detection. For the future, it seems indispensable to abandon some traditional concepts which lead us to consider that the only exploitable renal function is represented by excretion. The kidney has other functions; one of the most interesting seems to be the function of uptake of heavy metals and toxic substances, a study of which is only possible using radionuclides. A new generation of radioactive tests based on a study of uptake and also on a study of other renal functions may provide dynamic or quantitative data which physician urgently need

Layer 6 cortical neurons require Reelin-Dab1 signaling for cellular orientation, Golgi deployment, and directed neurite growth into the marginal zone.

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O'Dell, Ryan S; Ustine, Candida J M; Cameron, David A; Lawless, Sean M; Williams, Rebecca M; Zipfel, Warren R; Olson, Eric C

2012-07-07

The secreted ligand Reelin is believed to regulate the translocation of prospective layer 6 (L6) neocortical neurons into the preplate, a loose layer of pioneer neurons that overlies the ventricular zone. Recent studies have also suggested that Reelin controls neuronal orientation and polarized dendritic growth during this period of early cortical development. To explicitly characterize and quantify how Reelin controls this critical aspect of neurite initiation and growth we used a new ex utero explant model of early cortical development to selectively label a subset of L6 cortical neurons for complete 3-D reconstruction. The total neurite arbor sizes of neurons in Reelin-deficient (reeler mutant) and Dab1-deficient (Reelin-non-responsive scrambler mutant) cortices were quantified and unexpectedly were not different than control arbor lengths (p = 0.51). For each mutant, however, arbor organization was markedly different: mutant neurons manifested more primary processes (neurites emitted directly from the soma) than wild type, and these neurites were longer and displayed less branching. Reeler and scrambler mutant neurites extended tangentially rather than radially, and the Golgi apparatus that normally invests the apical neurite was compact in both reeler and scrambler mutants. Mutant cortices also exhibited a neurite "exclusion zone" which was relatively devoid of L6 neuron neurites and extended at least 15 μm beneath the pial surface, an area corresponding to the marginal zone (MZ) in the wild type explants. The presence of an exclusion zone was also indicated in the orientation of mutant primary neurite and neuronal somata, which failed to adopt angles within ~20˚ of the radial line to the pial surface. Injection of recombinant Reelin to reeler, but not scrambler, mutant cortices fully rescued soma orientation, Golgi organization, and dendritic projection defects within four hrs. These findings indicate Reelin promotes directional dendritic growth into

TFG facilitates outer coat disassembly on COPII transport carriers to promote tethering and fusion with ER-Golgi intermediate compartments.

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Hanna, Michael G; Block, Samuel; Frankel, E B; Hou, Feng; Johnson, Adam; Yuan, Lin; Knight, Gavin; Moresco, James J; Yates, John R; Ashton, Randolph; Schekman, Randy; Tong, Yufeng; Audhya, Anjon

2017-09-12

The conserved coat protein complex II (COPII) mediates the initial steps of secretory protein trafficking by assembling onto subdomains of the endoplasmic reticulum (ER) in two layers to generate cargo-laden transport carriers that ultimately fuse with an adjacent ER-Golgi intermediate compartment (ERGIC). Here, we demonstrate that Trk-fused gene (TFG) binds directly to the inner layer of the COPII coat. Specifically, the TFG C terminus interacts with Sec23 through a shared interface with the outer COPII coat and the cargo receptor Tango1/cTAGE5. Our findings indicate that TFG binding to Sec23 outcompetes these other associations in a concentration-dependent manner and ultimately promotes outer coat dissociation. Additionally, we demonstrate that TFG tethers vesicles harboring the inner COPII coat, which contributes to their clustering between the ER and ERGIC in cells. Together, our studies define a mechanism by which COPII transport carriers are retained locally at the ER/ERGIC interface after outer coat disassembly, which is a prerequisite for fusion with ERGIC membranes.

GOLGA2, encoding a master regulator of golgi apparatus, is mutated in a patient with a neuromuscular disorder.

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Shamseldin, Hanan E; Bennett, Alexis H; Alfadhel, Majid; Gupta, Vandana; Alkuraya, Fowzan S

2016-02-01

Golgi apparatus (GA) is a membrane-bound organelle that serves a multitude of critical cellular functions including protein secretion and sorting, and cellular polarity. Many Mendelian diseases are caused by mutations in genes encoding various components of GA. GOLGA2 encodes GM130, a necessary component for the assembly of GA as a single complex, and its deficiency has been found to result in severe cellular phenotypes. We describe the first human patient with a homozygous apparently loss of function mutation in GOLGA2. The phenotype is a neuromuscular disorder characterized by developmental delay, seizures, progressive microcephaly, and muscular dystrophy. Knockdown of golga2 in zebrafish resulted in severe skeletal muscle disorganization and microcephaly recapitulating loss of function human phenotype. Our data suggest an important developmental role of GM130 in humans and zebrafish.

Quantitative susceptibility mapping of human brain at 3T: a multisite reproducibility study.

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Lin, P-Y; Chao, T-C; Wu, M-L

2015-03-01

Quantitative susceptibility mapping of the human brain has demonstrated strong potential in examining iron deposition, which may help in investigating possible brain pathology. This study assesses the reproducibility of quantitative susceptibility mapping across different imaging sites. In this study, the susceptibility values of 5 regions of interest in the human brain were measured on 9 healthy subjects following calibration by using phantom experiments. Each of the subjects was imaged 5 times on 1 scanner with the same procedure repeated on 3 different 3T systems so that both within-site and cross-site quantitative susceptibility mapping precision levels could be assessed. Two quantitative susceptibility mapping algorithms, similar in principle, one by using iterative regularization (iterative quantitative susceptibility mapping) and the other with analytic optimal solutions (deterministic quantitative susceptibility mapping), were implemented, and their performances were compared. Results show that while deterministic quantitative susceptibility mapping had nearly 700 times faster computation speed, residual streaking artifacts seem to be more prominent compared with iterative quantitative susceptibility mapping. With quantitative susceptibility mapping, the putamen, globus pallidus, and caudate nucleus showed smaller imprecision on the order of 0.005 ppm, whereas the red nucleus and substantia nigra, closer to the skull base, had a somewhat larger imprecision of approximately 0.01 ppm. Cross-site errors were not significantly larger than within-site errors. Possible sources of estimation errors are discussed. The reproducibility of quantitative susceptibility mapping in the human brain in vivo is regionally dependent, and the precision levels achieved with quantitative susceptibility mapping should allow longitudinal and multisite studies such as aging-related changes in brain tissue magnetic susceptibility. © 2015 by American Journal of Neuroradiology.

Reproducibility of radionuclide gastroesophageal reflux studies using quantitative parameters and potential role of quantitative assessment in follow-up

International Nuclear Information System (INIS)

Fatima, S.; Khursheed, K.; Nasir, W.; Saeed, M.A.; Fatmi, S.; Jafri, S.; Asghar, S.

2004-01-01

Radionuclide gastroesophageal reflux studies have been widely used in the assessment of gastroesophageal reflux disease (GERD) in infants and children. Various qualitative and quantitative parameters have been used for the interpretation of reflux studies but there is little consensus on the use of these parameters in routine gastroesophageal reflux scintigraphic studies. Aim of this study was to evaluate the methodological issues underlying the qualitative and quantitative assessment of gastroesophageal reflux and to determine the potential power of the reflux index calculation in follow-up assessment of the reflux positive patients. Methods: Total 147 patients suffering from recurrent lower respiratory tract infection, asthma and having strong clinical suspicion of GER were recruited in the study. Dynamic scintigraphic study was acquired for 30 minutes after oral administration of 99mTc phytate. Each study was analyzed three times by two nuclear medicine physicians. Clinical symptoms were graded according to predefined criteria and there correlation with severity reflux was done. Time activity curves were generated by drawing ROIs from esophagus. Reflux index was calculated by the standard formula and cut off value of 4% was used for RI calculation. Reflux indices were used for follow-up assessments in reflux positive patients. Kappa statistics and chi square test were used to evaluate the agreement and concordance between qualitative and quantitative parameters. Results: Tlae over all incidence of reflux in total study population was 63.94 %( 94 patients). The kappa value for both qualitative and quantitative parameters showed good agreement for intra and inter-observer reproducibility (kappa value > 0.75). Concordance between visual analysis and time activity curves was not observed. Reflux index and visuat interpretation shows concordance in the interpretation. The severity of clinical symptoms was directly related to the severity of the reflux observed in the

Analog to digital workflow improvement: a quantitative study.

Science.gov (United States)

Wideman, Catherine; Gallet, Jacqueline

2006-01-01

This study tracked a radiology department's conversion from utilization of a Kodak Amber analog system to a Kodak DirectView DR 5100 digital system. Through the use of ProModel Optimization Suite, a workflow simulation software package, significant quantitative information was derived from workflow process data measured before and after the change to a digital system. Once the digital room was fully operational and the radiology staff comfortable with the new system, average patient examination time was reduced from 9.24 to 5.28 min, indicating that a higher patient throughput could be achieved. Compared to the analog system, chest examination time for modality specific activities was reduced by 43%. The percentage of repeat examinations experienced with the digital system also decreased to 8% vs. the level of 9.5% experienced with the analog system. The study indicated that it is possible to quantitatively study clinical workflow and productivity by using commercially available software.

Golgi Outpost Synthesis Impaired by Toxic Polyglutamine Proteins Contributes to Dendritic Pathology in Neurons

Directory of Open Access Journals (Sweden)

Chang Geon Chung

2017-07-01

Full Text Available Dendrite aberration is a common feature of neurodegenerative diseases caused by protein toxicity, but the underlying mechanisms remain largely elusive. Here, we show that nuclear polyglutamine (polyQ toxicity resulted in defective terminal dendrite elongation accompanied by a loss of Golgi outposts (GOPs and a decreased supply of plasma membrane (PM in Drosophila class IV dendritic arborization (da (C4 da neurons. mRNA sequencing revealed that genes downregulated by polyQ proteins included many secretory pathway-related genes, including COPII genes regulating GOP synthesis. Transcription factor enrichment analysis identified CREB3L1/CrebA, which regulates COPII gene expression. CrebA overexpression in C4 da neurons restores the dysregulation of COPII genes, GOP synthesis, and PM supply. Chromatin immunoprecipitation (ChIP-PCR revealed that CrebA expression is regulated by CREB-binding protein (CBP, which is sequestered by polyQ proteins. Furthermore, co-overexpression of CrebA and Rac1 synergistically restores the polyQ-induced dendrite pathology. Collectively, our results suggest that GOPs impaired by polyQ proteins contribute to dendrite pathology through the CBP-CrebA-COPII pathway.

GOLGA2/GM130, cis-Golgi matrix protein, is a novel target of anticancer gene therapy.

Science.gov (United States)

Chang, Seung-Hee; Hong, Seong-Ho; Jiang, Hu-Lin; Minai-Tehrani, Arash; Yu, Kyeong-Nam; Lee, Jae-Ho; Kim, Ji-Eun; Shin, Ji-Young; Kang, Bitna; Park, Sungjin; Han, Kiwon; Chae, Chanhee; Cho, Myung-Haing

2012-11-01

Achievement of long-term survival of patients with lung cancer treated with conventional chemotherapy is still difficult for treatment of metastatic and advanced tumors. Despite recent progress in investigational therapies, survival rates are still disappointingly low and novel adjuvant and systemic therapies are urgently needed. A recently elucidated secretory pathway is attracting considerable interest as a promising anticancer target. The cis-Golgi matrix protein, GOLGA2/GM130, plays an important role in glycosylation and transport of protein in the secretory pathway. In this study, the effects of short hairpin RNA (shRNA) constructs targeting GOLGA2/GM130 (shGOLGA2) on autophagy and lung cancer growth were evaluated in vitro and in vivo. Downregulation of GOLGA2/GM130 led to induction of autophagy and inhibition of glycosylation in A549 cells and in the lungs of K-ras(LA1) mice. Furthermore, downregulation of GOLGA2/GM130 decreased angiogenesis and cancer cell invasion in vitro and suppressed tumorigenesis in lung cancer mice model. The tumor specificity of sequence targeting GOLGA2/GM130 was also demonstrated. Taken together, these results suggest that induction of autophagy by shGOLGA2 may induce cell death rather than cell survival. Therefore, downregulation of GOLGA2/GM130 may be a potential therapeutic option for lung cancer.

Using Digital Archives in Quantitative Discourse Studies: Methodological Reflections

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Kobie Van Krieken

2015-12-01

Full Text Available This methodological essay discusses the possibilities of using digital archives in quantitative discourse studies. I illustrate these possibilities by discussing a study in which the digital archive Delpher was used to build a relatively large corpus of newspaper narratives (N=300 in order to test hypotheses about the historical development of linguistic features associated with objective and subjective reporting. The large amount of data collected in digital archives like Delpher facilitates the construction of corpora for such hypothesis-driven studies. However, the collection of newspaper articles on Delpher in fact constitutes only a small, non-random and continuously changing selection of all available data. Due to these characteristics, the use of Delpher jeopardizes two core values of quantitative empirical research: the generalizability and the replicability of findings. Although these issues cannot be easily overcome, I argue that digital archives have the potential to broaden the methodological scope of discourse studies and increase the overall significance of the field.

Studying learning in the healthcare setting: the potential of quantitative diary methods.

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Ciere, Yvette; Jaarsma, Debbie; Visser, Annemieke; Sanderman, Robbert; Snippe, Evelien; Fleer, Joke

2015-08-01

Quantitative diary methods are longitudinal approaches that involve the repeated measurement of aspects of peoples' experience of daily life. In this article, we outline the main characteristics and applications of quantitative diary methods and discuss how their use may further research in the field of medical education. Quantitative diary methods offer several methodological advantages, such as measuring aspects of learning with great detail, accuracy and authenticity. Moreover, they enable researchers to study how and under which conditions learning in the health care setting occurs and in which way learning can be promoted. Hence, quantitative diary methods may contribute to theory development and the optimization of teaching methods in medical education.

The Prion-like Domain in the Exomer-Dependent Cargo Pin2 Serves as a trans-Golgi Retention Motif

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Alicja M. Ritz

2014-04-01

Full Text Available Prion and prion-like domains (PLDs are found in many proteins throughout the animal kingdom. We found that the PLD in the S. cerevisiae exomer-dependent cargo protein Pin2 is involved in the regulation of protein transport and localization. The domain serves as a Pin2 retention signal in the trans-Golgi network (TGN. Pin2 is localized in a polarized fashion at the plasma membrane of the bud early in the cell cycle and the bud neck at cytokinesis. This polarized localization is dependent on both exo- and endocytosis. Upon environmental stress, Pin2 is rapidly endocytosed, and the PLD aggregates and causes sequestration of Pin2. The aggregation of Pin2 is reversible upon stress removal and Pin2 is rapidly re-exported to the plasma membrane. Altogether, these data uncover a role for PLDs as protein localization elements.

A Quantitative Study Identifying Political Strategies Used by Principals of Dual Language Programs

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Girard, Guadalupe

2017-01-01

Purpose. The purpose of this quantitative study was to identify the external and internal political strategies used by principals that allow them to successfully navigate the political environment surrounding dual language programs. Methodology. This quantitative study used descriptive research to collect, analyze, and report data that identified…

Quantitative Methods in the Study of Local History

Science.gov (United States)

Davey, Pene

1974-01-01

The author suggests how the quantitative analysis of data from census records, assessment roles, and newspapers may be integrated into the classroom. Suggestions for obtaining quantitative data are provided. (DE)

Dsc E3 ligase localization to the Golgi requires the ATPase Cdc48 and cofactor Ufd1 for activation of sterol regulatory element-binding protein in fission yeast.

Science.gov (United States)

Burr, Risa; Ribbens, Diedre; Raychaudhuri, Sumana; Stewart, Emerson V; Ho, Jason; Espenshade, Peter J

2017-09-29

Sterol regulatory element-binding proteins (SREBPs) in the fission yeast Schizosaccharomyces pombe regulate lipid homeostasis and the hypoxic response under conditions of low sterol or oxygen availability. SREBPs are cleaved in the Golgi through the combined action of the Dsc E3 ligase complex, the rhomboid protease Rbd2, and the essential ATPases associated with diverse cellular activities (AAA + ) ATPase Cdc48. The soluble SREBP N-terminal transcription factor domain is then released into the cytosol to enter the nucleus and regulate gene expression. Previously, we reported that Cdc48 binding to Rbd2 is required for Rbd2-mediated SREBP cleavage. Here, using affinity chromatography and mass spectrometry experiments, we identified Cdc48-binding proteins in S. pombe , generating a list of many previously unknown potential Cdc48-binding partners. We show that the established Cdc48 cofactor Ufd1 is required for SREBP cleavage but does not interact with the Cdc48-Rbd2 complex. Cdc48-Ufd1 is instead required at a step prior to Rbd2 function, during Golgi localization of the Dsc E3 ligase complex. Together, these findings demonstrate that two distinct Cdc48 complexes, Cdc48-Ufd1 and Cdc48-Rbd2, are required for SREBP activation and low-oxygen adaptation in S. pombe . © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Violacein induces death of resistant leukaemia cells via kinome reprogramming, endoplasmic reticulum stress and Golgi apparatus collapse.

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Karla C S Queiroz

Full Text Available It is now generally recognised that different modes of programmed cell death (PCD are intimately linked to the cancerous process. However, the mechanism of PCD involved in cancer chemoprevention is much less clear and may be different between types of chemopreventive agents and tumour cell types involved. Therefore, from a pharmacological view, it is crucial during the earlier steps of drug development to define the cellular specificity of the candidate as well as its capacity to bypass dysfunctional tumoral signalling pathways providing insensitivity to death stimuli. Studying the cytotoxic effects of violacein, an antibiotic dihydro-indolone synthesised by an Amazon river Chromobacterium, we observed that death induced in CD34(+/c-Kit(+/P-glycoprotein(+/MRP1(+ TF1 leukaemia progenitor cells is not mediated by apoptosis and/or autophagy, since biomarkers of both types of cell death were not significantly affected by this compound. To clarify the working mechanism of violacein, we performed kinome profiling using peptide arrays to yield comprehensive descriptions of cellular kinase activities. Pro-death activity of violacein is actually carried out by inhibition of calpain and DAPK1 and activation of PKA, AKT and PDK, followed by structural changes caused by endoplasmic reticulum stress and Golgi apparatus collapse, leading to cellular demise. Our results demonstrate that violacein induces kinome reprogramming, overcoming death signaling dysfunctions of intrinsically resistant human leukaemia cells.

A study on quantitative V and V of safety-critical software

International Nuclear Information System (INIS)

Eom, H. S.; Kang, H. G.; Chang, S. C.; Ha, J. J.; Son, H. S.

2004-03-01

Recently practical needs have required quantitative features for the software reliability for Probabilistic Safety Assessment which is one of the important methods being used in assessing the overall safety of nuclear power plant. But the conventional assessment methods of software reliability could not provide enough information for PSA of NPP, therefore current assessments of a digital system which includes safety-critical software usually exclude the software part or use arbitrary values. This paper describes a Bayesian Belief Networks based method that models the rule-based qualitative software assessment method for a practical use and can produce quantitative results for PSA. The framework was constructed by utilizing BBN that can combine the qualitative and quantitative evidence relevant to the reliability of safety-critical software and can infer a conclusion in a formal and a quantitative way. The case study was performed by applying the method for assessing the quality of software requirement specification of safety-critical software that will be embedded in reactor protection system

The Selection of Quantitative Undergraduate Fields of Study: Direct and Indirect Influences.

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Ethington, Corinna A.; Wolfle, Lee M.

In order to increase women's representation among quantitative degrees, Berryman (1985) suggested two strategies: (1) increase women's share of the initial mathematical/scientific pool; or (2) reduce attrition from the pool. However, current research indicates that the decision to enter a quantitative field of study for women is the result of a…

Chimeric forms of furin and TGN38 are transported with the plasma membrane in the trans-Golgi network via distinct endosomal pathways.

Science.gov (United States)

Mallet, W G; Maxfield, F R

1999-07-26

Furin and TGN38 are menbrane proteins that cycle between the plasma membrane and the trans-Golgi network (TGN), each maintaining a predominant distribution in the TGN. We have used chimeric proteins with an extracellular Tac domain and the cytoplasmic domain of TGN38 or furin to study the trafficking of these proteins in endosomes. Previously, we demonstrated that the postendocytic trafficking of Tac-TGN38 to the TGN is via the endocytic recycling pathway (Ghosh, R.N.,W.G. Mallet,T.T. Soe,T.E.McGraw, and F.R. Maxfield.1998.J. Cell Biol.142:923-936). Here we show that internalized Tac-furin is delivered to the TGN through late endosomes, bypassing the endocytic recycling compartment. The transport of Tac-furin from late endosomes to the TGN appears to proceed via an efficient, single-pass mechanism. Delivery of Tac-furin but not Tac-TGN38 to the TGN is blocked by nocodazole, and the two pathways are also differentially affected by wortmannin. These studies demonstrate the existence of two independentpathways for endosomal transport of proteins to the TGN from the plasma membrane.

Traditions and Transitions in Quantitative Societal Culture Research in Organization Studies

DEFF Research Database (Denmark)

Peterson, Mark, F.; Søndergaard, Mikael

2011-01-01

Quantitative societal culture research (QSCR) in organization studies crystallizes a configuration of social science perspectives and methods that became prominent in the 1970s. We consider the qualities of and boundaries around cultural groups that this tradition emphasizes, and other...... characteristics of cultural groups that it does not emphasize. Current debates surrounding this tradition reflect both recent social science innovations and rediscoveries of early social science perspectives. Our analysis of quantitative cross-cultural societal research in organization studies considers...... this process of crystallization, innovation and rediscovery. We suggest ways to address current controversies and promote conversations with other research approaches....

Expermental Studies of quantitative evaluation using HPLC

Directory of Open Access Journals (Sweden)

Ki Rok Kwon

2005-06-01

Full Text Available Methods : This study was conducted to carry out quantitative evaluation using HPLC Content analysis was done using HPLC Results : According to HPLC analysis, each BVA-1 contained approximately 0.36㎍ melittin, and BVA-2 contained approximately 0.54㎍ melittin. But the volume of coating was so minute, slight difference exists between each needle. Conclusion : Above results indicate that the bee venom acupuncture can complement shortcomings of syringe usage as a part of Oriental medicine treatment, but extensive researches should be done for further verification.

A quantitative study of nanoparticle skin penetration with interactive segmentation.

Science.gov (United States)

Lee, Onseok; Lee, See Hyun; Jeong, Sang Hoon; Kim, Jaeyoung; Ryu, Hwa Jung; Oh, Chilhwan; Son, Sang Wook

2016-10-01

In the last decade, the application of nanotechnology techniques has expanded within diverse areas such as pharmacology, medicine, and optical science. Despite such wide-ranging possibilities for implementation into practice, the mechanisms behind nanoparticle skin absorption remain unknown. Moreover, the main mode of investigation has been qualitative analysis. Using interactive segmentation, this study suggests a method of objectively and quantitatively analyzing the mechanisms underlying the skin absorption of nanoparticles. Silica nanoparticles (SNPs) were assessed using transmission electron microscopy and applied to the human skin equivalent model. Captured fluorescence images of this model were used to evaluate degrees of skin penetration. These images underwent interactive segmentation and image processing in addition to statistical quantitative analyses of calculated image parameters including the mean, integrated density, skewness, kurtosis, and area fraction. In images from both groups, the distribution area and intensity of fluorescent silica gradually increased in proportion to time. Since statistical significance was achieved after 2 days in the negative charge group and after 4 days in the positive charge group, there is a periodic difference. Furthermore, the quantity of silica per unit area showed a dramatic change after 6 days in the negative charge group. Although this quantitative result is identical to results obtained by qualitative assessment, it is meaningful in that it was proven by statistical analysis with quantitation by using image processing. The present study suggests that the surface charge of SNPs could play an important role in the percutaneous absorption of NPs. These findings can help achieve a better understanding of the percutaneous transport of NPs. In addition, these results provide important guidance for the design of NPs for biomedical applications.

Predictive value of serum Golgi protein 73 for prominent hepatic necroinflammation in chronic HBV infection.

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Xu, Zhengju; Shen, Jiankun; Pan, Xingnan; Wei, Meijuan; Liu, Liguan; Wei, Kaipeng; Liu, Lifei; Yang, Huanwen; Huang, Jinfa

2018-06-01

As a noninvasive marker, serum alanine aminotransferase (ALT) has limitations, because a large proportion of patients chronically infected with hepatitis B virus (HBV) suffer from severe hepatic necroinflammation, but have normal or mildly elevated ALT. In the present study, we aimed to investigate the potential value of serum Golgi protein 73 (GP73) in predicting significant hepatic necroinflamation among chronic HBV infected patients. A cohort of 497 chronic HBV infected patients was retrospectively recruited. Liver biopsy was performed in all patients and serum GP73 levels were measured by enzyme-linked immunosorbent assay. Serum GP73 increased in parallel with the increase in hepatic necroinflammatory activity grade (r = 0.682) and the stage of liver fibrosis (r = 0.539). The positive correlation of serum GP73 with the degree of hepatic necroinflammatory activity was statistically significant, while serum GP73 with the stage of liver fibrosis was weaker than that with hepatic necroinflammation. Furthermore, serum GP73 levels were significantly greater in patients with normal or mildly elevated ALT and significant hepatic necroinflammation (≥G2) than in patients with minimal to mild hepatic necroinflammation. The sensitivity and specificity of GP73 for the diagnosis of G2 hepatic necroinflammation was 42.35% and 95.0%, respectively, at a cut-off value of 88.38 ng/mL. When the cut-off value was set at 124.76 ng/mL, the sensitivity and specificity of GP73 for the diagnosis of G3 hepatic necroinflammation was 55.56% and 97.29%, respectively. These findings indicate that GP73 holds promise as an important candidate for diagnosing significant hepatic necroinflammation. © 2018 Wiley Periodicals, Inc.

CT quantitative diagnosis in fatty liver: a clinical study

International Nuclear Information System (INIS)

He Wen; Qian Linxue; Zhao Jixue; Ma Daqing; Feng Jie; Hu Zhihai

2001-01-01

Objective: To establish the CT criteria of quantitative diagnosis for liver steatosis by means of studying the CT features of fatty liver cases proven histologically. Methods: Twenty-eight cases of fatty liver were underwent non-enhanced CT scan, and the attenuation of liver parenchyma was measured. To differentiate the degree of fatty liver, the mean CT value and the relative density of hepatic vessels were observed. The quantitative diagnosis was made according to the CT number threshold and the criteria of relative density of hepatic vessels, respectively. Results: Among the 28 cases, there were 17 cases of mild steatosis with mean CT number of 46 HU (32-65 HU), 7 cases of middle degree fatty liver with mean CT number of 28 HU (15-38 HU), and 4 cases of sever fatty liver with mean CT number of 0.2 HU (-7-11 HU). For the relative density of hepatic vessels, 16 of the 17 cases of mild fatty liver had a appearance of hepatic vessels immersion and 1 mild case had reverse hepatic vessels display, 6 of 7 middle degree cases had reverse hepatic vessels display with 1 case having the appearance of hepatic vessels immersion, and all the 4 case of sever steatosis had the appearance of reverse hepatic vessels display with sharp contrast between vessels and the liver parenchyma. The accuracy of quantitative diagnosis was 65.9% and 93.1% by means of criteria of CT number threshold and relative density of hepatic vessels, respectively (x 2 = 7.153, P < 0.01). Conclusion: The criteria of relative density of hepatic vessels is more reliable than that of CT number threshold in quantitative diagnosis of fatty liver

Study of the quantitative analysis approach of maintenance by the Monte Carlo simulation method

International Nuclear Information System (INIS)

Shimizu, Takashi

2007-01-01

This study is examination of the quantitative valuation by Monte Carlo simulation method of maintenance activities of a nuclear power plant. Therefore, the concept of the quantitative valuation of maintenance that examination was advanced in the Japan Society of Maintenology and International Institute of Universality (IUU) was arranged. Basis examination for quantitative valuation of maintenance was carried out at simple feed water system, by Monte Carlo simulation method. (author)

System-wide organization of actin cytoskeleton determines organelle transport in hypocotyl plant cells

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Nowak, Jacqueline; Ivakov, Alexander; Somssich, Marc; Persson, Staffan; Nikoloski, Zoran

2017-01-01

The actin cytoskeleton is an essential intracellular filamentous structure that underpins cellular transport and cytoplasmic streaming in plant cells. However, the system-level properties of actin-based cellular trafficking remain tenuous, largely due to the inability to quantify key features of the actin cytoskeleton. Here, we developed an automated image-based, network-driven framework to accurately segment and quantify actin cytoskeletal structures and Golgi transport. We show that the actin cytoskeleton in both growing and elongated hypocotyl cells has structural properties facilitating efficient transport. Our findings suggest that the erratic movement of Golgi is a stable cellular phenomenon that might optimize distribution efficiency of cell material. Moreover, we demonstrate that Golgi transport in hypocotyl cells can be accurately predicted from the actin network topology alone. Thus, our framework provides quantitative evidence for system-wide coordination of cellular transport in plant cells and can be readily applied to investigate cytoskeletal organization and transport in other organisms. PMID:28655850

Papel del diacilglicerol en el tráfico de membranas en la zona entre el retículo endoplasmático y el complejo de Golgi, El

OpenAIRE

Fernández Ulibarri, Inés

2008-01-01

DE LA TESIS:El DAG es esencial para formar los intermediarios de transporte que se dirigen a la membrana plasmática. Sin embargo, no existen evidencias de su posible participación en las etapas tempranas de la vía secretora. Por tanto, nos centramos en averiguar la implicación del DAG en el transporte de proteínas en la zona del ER/Golgi. Para ello, utilizamos una variedad de fármacos conocidos que inhiben las enzimas responsables de la producción del DAG. Nuestros datos indican que el DAG es...

El Papel del diacilglicerol en el tráfico de membranas en la zona entre el retículo endoplasmático y el complejo de Golgi

OpenAIRE

Fernández Ulibarri, Inés

2008-01-01

[spa] DE LA TESIS: El DAG es esencial para formar los intermediarios de transporte que se dirigen a la membrana plasmática. Sin embargo, no existen evidencias de su posible participación en las etapas tempranas de la vía secretora. Por tanto, nos centramos en averiguar la implicación del DAG en el transporte de proteínas en la zona del ER/Golgi. Para ello, utilizamos una variedad de fármacos conocidos que inhiben las enzimas responsables de la producción del DAG. Nuestros datos indican que el...

Quantitative radiomics studies for tissue characterization: a review of technology and methodological procedures.

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Larue, Ruben T H M; Defraene, Gilles; De Ruysscher, Dirk; Lambin, Philippe; van Elmpt, Wouter

2017-02-01

Quantitative analysis of tumour characteristics based on medical imaging is an emerging field of research. In recent years, quantitative imaging features derived from CT, positron emission tomography and MR scans were shown to be of added value in the prediction of outcome parameters in oncology, in what is called the radiomics field. However, results might be difficult to compare owing to a lack of standardized methodologies to conduct quantitative image analyses. In this review, we aim to present an overview of the current challenges, technical routines and protocols that are involved in quantitative imaging studies. The first issue that should be overcome is the dependency of several features on the scan acquisition and image reconstruction parameters. Adopting consistent methods in the subsequent target segmentation step is evenly crucial. To further establish robust quantitative image analyses, standardization or at least calibration of imaging features based on different feature extraction settings is required, especially for texture- and filter-based features. Several open-source and commercial software packages to perform feature extraction are currently available, all with slightly different functionalities, which makes benchmarking quite challenging. The number of imaging features calculated is typically larger than the number of patients studied, which emphasizes the importance of proper feature selection and prediction model-building routines to prevent overfitting. Even though many of these challenges still need to be addressed before quantitative imaging can be brought into daily clinical practice, radiomics is expected to be a critical component for the integration of image-derived information to personalize treatment in the future.

Evaluation of a magnetic particles-based chemiluminescence enzyme immunoassay for Golgi protein 73 in human serum.

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Liu, Xiangyi; Wan, Xiaohua; Lu, Sheng; Zhang, Lijun; Yu, Shaohua; Lu, Xinxin

2015-05-20

Golgi protein 73 (GP73) is regarded as a potential serum biomarker for early diagnosis of hepatocellular carcinoma (HCC). We developed a rapid magnetic particles-based chemiluminescence enzyme immunoassay (MPs-CLEIA) for the determination of serum GP73. Fluorescein isothiocyanate (FITC) and alkaline phosphatase (ALP) were used to label 2 different monoclonal antibodies to GP73. Serum GP73 was captured with labeled antibodies and formed a sandwiched immunoreaction. The magnetic particles (MPs) coated with anti-FITC antibody were used as a means of separation of the GP73 protein from other serum proteins. After adding the enzyme substrate solution, the relative light unit (RLU) was measured. A MPs-CLEIA for serum GP73 was established and evaluated. The RLU was directly proportional to the concentration of GP73. The method linearity was 5-600 μg/l. Limit of the blank was 2.19 μg/l. The intra- and inter-assay imprecision was 73-0.89), and the sensitivity and specificity, with cut-off value of 115.6 μg/l, were 75.4% and 92.1%, respectively. The proposed method demonstrates an acceptable performance for quantifying serum GP73. This assay could be appropriate for routine use in clinical laboratories. Copyright © 2015 Elsevier B.V. All rights reserved.

Quantitative studies of water and sanitation utilities: a literature survey

OpenAIRE

Berg, Sanford V; Marques, Rui Cunha

2010-01-01

This paper performs a literature update of quantitative studies of water and sanitation services (WSS). There are 190 studies which use cost or production functions to evaluate the performance of WSS utilities. The studies examine (1) the scale, scope or density economies of utilities in a particular country or region, (2) the influence of ownership on efficiency, (3) the existence and power of incentives associated with different governance systems (including external regulation), and (4) pe...

Simulation and the Development of Clinical Judgment: A Quantitative Study

Science.gov (United States)

Holland, Susan

2015-01-01

The purpose of this quantitative pretest posttest quasi-experimental research study was to explore the effect of the NESD on clinical judgment in associate degree nursing students and compare the differences between groups when the Nursing Education Simulation Design (NESD) guided simulation in order to identify educational strategies promoting…

A Qualitative and Quantitative Assay to Study DNA/Drug Interaction ...

African Journals Online (AJOL)

Research Article. A Qualitative and Quantitative Assay to Study. DNA/Drug Interaction Based on Sequence Selective. Inhibition of Restriction Endonucleases. Syed A Hassan1*, Lata Chauhan2, Ritu Barthwal2 and Aparna Dixit3. 1 Faculty of Computing and Information Technology, King Abdul Aziz University, Rabigh-21911 ...

Selecting the most appropriate inferential statistical test for your quantitative research study.

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Bettany-Saltikov, Josette; Whittaker, Victoria Jane

2014-06-01

To discuss the issues and processes relating to the selection of the most appropriate statistical test. A review of the basic research concepts together with a number of clinical scenarios is used to illustrate this. Quantitative nursing research generally features the use of empirical data which necessitates the selection of both descriptive and statistical tests. Different types of research questions can be answered by different types of research designs, which in turn need to be matched to a specific statistical test(s). Discursive paper. This paper discusses the issues relating to the selection of the most appropriate statistical test and makes some recommendations as to how these might be dealt with. When conducting empirical quantitative studies, a number of key issues need to be considered. Considerations for selecting the most appropriate statistical tests are discussed and flow charts provided to facilitate this process. When nursing clinicians and researchers conduct quantitative research studies, it is crucial that the most appropriate statistical test is selected to enable valid conclusions to be made. © 2013 John Wiley & Sons Ltd.

Subjective Quantitative Studies of Human Agency

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Alkire, Sabina

2005-01-01

Amartya Sen's writings have articulated the importance of human agency, and identified the need for information on agency freedom to inform our evaluation of social arrangements. Many approaches to poverty reduction stress the need for empowerment. This paper reviews "subjective quantitative measures of human agency at the individual level." It…

Golgi Analysis of Neuron Morphology in the Presumptive Somatosensory Cortex and Visual Cortex of the Florida Manatee (Trichechus manatus latirostris).

Science.gov (United States)

Reyes, Laura D; Harland, Tessa; Reep, Roger L; Sherwood, Chet C; Jacobs, Bob

2016-01-01

The current study investigates neuron morphology in presumptive primary somatosensory (S1) and primary visual (V1) cortices of the Florida manatee (Trichechus manatus latirostris) as revealed by Golgi impregnation. Sirenians, including manatees, have an aquatic lifestyle, a large body size, and a relatively large lissencephalic brain. The present study examines neuron morphology in 3 cortical areas: in S1, dorsolateral cortex area 1 (DL1) and cluster cortex area 2 (CL2) and in V1, dorsolateral cortex area 4 (DL4). Neurons exhibited a variety of morphological types, with pyramidal neurons being the most common. The large variety of neuron types present in the manatee cortex was comparable to that seen in other eutherian mammals, except for rodents and primates, where pyramid-shaped neurons predominate. A comparison between pyramidal neurons in S1 and V1 indicated relatively greater dendritic branching in S1. Across all 3 areas, the dendritic arborization pattern of pyramidal neurons was also similar to that observed previously in the afrotherian rock hyrax, cetartiodactyls, opossums, and echidnas but did not resemble the widely bifurcated dendrites seen in the large-brained African elephant. Despite adaptations for an aquatic environment, manatees did not share specific neuron types such as tritufted and star-like neurons that have been found in cetaceans. Manatees exhibit an evolutionarily primitive pattern of cortical neuron morphology shared with most other mammals and do not appear to have neuronal specializations for an aquatic niche. © 2016 S. Karger AG, Basel.

Radioisotope studies for quantitative measurement of manganese absorption

International Nuclear Information System (INIS)

Helbig, U.

1981-01-01

Purpose of the present study was to quantitatively determine the manganese absorption in growing rats by means of radioisotopes. First of all the following factors had to be investigated, which are significant for this determination: Measurability of stable and radioactive Mn in rat tissues; labelling of stable Mn and distribution of stable and radioactive Mn in the organism; verification of the isotope dilution method and of the comparative balance method with regard to its applicability for the determination of the true Mn absorption. We useed male and female Sprague-Dawley rats. The most important results are summarized in the following: in some separate tissues measurement of stable Mn was accompanied by difficulties. The measurement of radioactive Mn however, could be performed without any problems. 10 d after i.m. injection of 54 Mn only 17% of the administered Mn was still detectable in the organism. However, there was no uniform tissue labelling found. Therefore it is possible to an only restricted extent to draw quantitative conclusions on the content of stable Mn. A high percentage of stable and radioactive Mn was found above all in the liver. The isotope dilution method permits by feces analysis to differentiate between unabsorbed Mn coming from the food and endogenic Mn coming from the organism itself. The effective Mn absorption was also determined by means of the comparative balance method. By means of the isotope dilution method we determined the quantitative Mn-absorption with staged Mn administration and the contribution of absorption and excretion to the homeostatic regulation mechanisms of Mn. We found that absorption and excretion help the organism to keep an almost constant Mn concentration even with a differing Mn supply. (orig./MG) [de

Technological innovation in neurosurgery: a quantitative study.

Science.gov (United States)

Marcus, Hani J; Hughes-Hallett, Archie; Kwasnicki, Richard M; Darzi, Ara; Yang, Guang-Zhong; Nandi, Dipankar

2015-07-01

Technological innovation within health care may be defined as the introduction of a new technology that initiates a change in clinical practice. Neurosurgery is a particularly technology-intensive surgical discipline, and new technologies have preceded many of the major advances in operative neurosurgical techniques. The aim of the present study was to quantitatively evaluate technological innovation in neurosurgery using patents and peer-reviewed publications as metrics of technology development and clinical translation, respectively. The authors searched a patent database for articles published between 1960 and 2010 using the Boolean search term "neurosurgeon OR neurosurgical OR neurosurgery." The top 50 performing patent codes were then grouped into technology clusters. Patent and publication growth curves were then generated for these technology clusters. A top-performing technology cluster was then selected as an exemplar for a more detailed analysis of individual patents. In all, 11,672 patents and 208,203 publications related to neurosurgery were identified. The top-performing technology clusters during these 50 years were image-guidance devices, clinical neurophysiology devices, neuromodulation devices, operating microscopes, and endoscopes. In relation to image-guidance and neuromodulation devices, the authors found a highly correlated rapid rise in the numbers of patents and publications, which suggests that these are areas of technology expansion. An in-depth analysis of neuromodulation-device patents revealed that the majority of well-performing patents were related to deep brain stimulation. Patent and publication data may be used to quantitatively evaluate technological innovation in neurosurgery.

A Quantitative Correlational Study of Teacher Preparation Program on Student Achievement

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Dingman, Jacob Blackstone

2010-01-01

The purpose of this quantitative correlational study was to identify the relationship between the type of teacher preparation program and student performance on the seventh and eighth grade mathematics state assessments in rural school settings. The study included a survey of a convenience sample of 36 teachers from Colorado and Washington school…

A Quantitative Study Examining Teacher Stress, Burnout, and Self-Efficacy

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Stephenson, Timar D.

2012-01-01

The purpose of this quantitative, correlational study was to examine the relationships between stress, burnout, and self-efficacy in public school teachers in the Turks and Caicos Islands. The Teacher Stress Inventory was used to collect data on teacher stress, the Maslach Burnout Inventory Educators Survey was used to obtain data on teacher…

Quantitative Structure-Activity Relationships and Docking Studies of Calcitonin Gene-Related Peptide Antagonists

DEFF Research Database (Denmark)

Jenssen, Håvard; Mehrabian, Mohadeseh; Kyani, Anahita

2012-01-01

Defining the role of calcitonin gene-related peptide in migraine pathogenesis could lead to the application of calcitonin gene-related peptide antagonists as novel migraine therapeutics. In this work, quantitative structure-activity relationship modeling of biological activities of a large range...... of calcitonin gene-related peptide antagonists was performed using a panel of physicochemical descriptors. The computational studies evaluated different variable selection techniques and demonstrated shuffling stepwise multiple linear regression to be superior over genetic algorithm-multiple linear regression....... The linear quantitative structure-activity relationship model revealed better statistical parameters of cross-validation in comparison with the non-linear support vector regression technique. Implementing only five peptide descriptors into this linear quantitative structure-activity relationship model...

A Comparative Study on Tobacco Cessation Methods: A Quantitative Systematic Review

Directory of Open Access Journals (Sweden)

Gholamreza Heydari

2014-01-01

Conclusions: Results of this review indicate that the scientific papers in the most recent decade recommend the use of NRT and Champix in combination with educational interventions. Additional research is needed to compare qualitative and quantitative studies for smoking cessation.

A REVIEW OF QUANTITATIVE METHODS FOR STUDIES OF MINERAL-CONTENT OF INTRAORAL INCIPIENT CARIES LESIONS

NARCIS (Netherlands)

TENBOSCH, JJ; ANGMARMANSSON, B

Modern prospective caries studies require the measurement of small changes in tooth mineral content. Quantitative measurements of changes in mineral content in a single caries lesion is desirable. Quantitative methods can be either destructive or non-destructive. The latter type permits longitudinal

Quantitative Correlational Study: Emotional Intelligence and Project Outcomes among Hispanics in Technology

Science.gov (United States)

Trejo, Arturo

2013-01-01

The present quantitative correlational research study explored relationships between Emotional Intelligence (EI) competencies, such as self-awareness, self-management, social awareness, and relationship management, and project management outcomes: scope creep, in-budget project cost, and project timeliness. The study was conducted within the…

Connecting qualitative observation and quantitative measurement for enhancing quantitative literacy in plant anatomy course

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Nuraeni, E.; Rahmat, A.

2018-05-01

Forming of cognitive schemes of plant anatomy concepts is performed by processing of qualitative and quantitative data obtained from microscopic observations. To enhancing student’s quantitative literacy, strategy of plant anatomy course was modified by adding the task to analyze quantitative data produced by quantitative measurement of plant anatomy guided by material course. Participant in this study was 24 biology students and 35 biology education students. Quantitative Literacy test, complex thinking in plant anatomy test and questioner used to evaluate the course. Quantitative literacy capability data was collected by quantitative literacy test with the rubric from the Association of American Colleges and Universities, Complex thinking in plant anatomy by test according to Marzano and questioner. Quantitative literacy data are categorized according to modified Rhodes and Finley categories. The results showed that quantitative literacy of biology education students is better than biology students.

GWAPower: a statistical power calculation software for genome-wide association studies with quantitative traits.

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Feng, Sheng; Wang, Shengchu; Chen, Chia-Cheng; Lan, Lan

2011-01-21

In designing genome-wide association (GWA) studies it is important to calculate statistical power. General statistical power calculation procedures for quantitative measures often require information concerning summary statistics of distributions such as mean and variance. However, with genetic studies, the effect size of quantitative traits is traditionally expressed as heritability, a quantity defined as the amount of phenotypic variation in the population that can be ascribed to the genetic variants among individuals. Heritability is hard to transform into summary statistics. Therefore, general power calculation procedures cannot be used directly in GWA studies. The development of appropriate statistical methods and a user-friendly software package to address this problem would be welcomed. This paper presents GWAPower, a statistical software package of power calculation designed for GWA studies with quantitative traits, where genetic effect is defined as heritability. Based on several popular one-degree-of-freedom genetic models, this method avoids the need to specify the non-centrality parameter of the F-distribution under the alternative hypothesis. Therefore, it can use heritability information directly without approximation. In GWAPower, the power calculation can be easily adjusted for adding covariates and linkage disequilibrium information. An example is provided to illustrate GWAPower, followed by discussions. GWAPower is a user-friendly free software package for calculating statistical power based on heritability in GWA studies with quantitative traits. The software is freely available at: http://dl.dropbox.com/u/10502931/GWAPower.zip.

A scoring system for appraising mixed methods research, and concomitantly appraising qualitative, quantitative and mixed methods primary studies in Mixed Studies Reviews.

Science.gov (United States)

Pluye, Pierre; Gagnon, Marie-Pierre; Griffiths, Frances; Johnson-Lafleur, Janique

2009-04-01

A new form of literature review has emerged, Mixed Studies Review (MSR). These reviews include qualitative, quantitative and mixed methods studies. In the present paper, we examine MSRs in health sciences, and provide guidance on processes that should be included and reported. However, there are no valid and usable criteria for concomitantly appraising the methodological quality of the qualitative, quantitative and mixed methods studies. To propose criteria for concomitantly appraising the methodological quality of qualitative, quantitative and mixed methods studies or study components. A three-step critical review was conducted. 2322 references were identified in MEDLINE, and their titles and abstracts were screened; 149 potentially relevant references were selected and the full-text papers were examined; 59 MSRs were retained and scrutinized using a deductive-inductive qualitative thematic data analysis. This revealed three types of MSR: convenience, reproducible, and systematic. Guided by a proposal, we conducted a qualitative thematic data analysis of the quality appraisal procedures used in the 17 systematic MSRs (SMSRs). Of 17 SMSRs, 12 showed clear quality appraisal procedures with explicit criteria but no SMSR used valid checklists to concomitantly appraise qualitative, quantitative and mixed methods studies. In two SMSRs, criteria were developed following a specific procedure. Checklists usually contained more criteria than needed. In four SMSRs, a reliability assessment was described or mentioned. While criteria for quality appraisal were usually based on descriptors that require specific methodological expertise (e.g., appropriateness), no SMSR described the fit between reviewers' expertise and appraised studies. Quality appraisal usually resulted in studies being ranked by methodological quality. A scoring system is proposed for concomitantly appraising the methodological quality of qualitative, quantitative and mixed methods studies for SMSRs. This

Critical review of a quantitative study of a specialty in high energy particle physics

International Nuclear Information System (INIS)

White, D.H.; Sullivan, D.

1980-01-01

A review is made of the authors' series of quantitative, historical, and social studies of the weak interactions of elementary particles. A short intellectual history, the quantitative methodology, and a summary of the papers analyzing specific episodes in this field are presented. The social organization of the field is described, and an overall policy for resource management is discussed. 6 figures, 3 tables

Integration of hydrothermal-energy economics: related quantitative studies

Energy Technology Data Exchange (ETDEWEB)

1982-08-01

A comparison of ten models for computing the cost of hydrothermal energy is presented. This comparison involved a detailed examination of a number of technical and economic parameters of the various quantitative models with the objective of identifying the most important parameters in the context of accurate estimates of cost of hydrothermal energy. Important features of various models, such as focus of study, applications, marked sectors covered, methodology, input data requirements, and output are compared in the document. A detailed sensitivity analysis of all the important engineering and economic parameters is carried out to determine the effect of non-consideration of individual parameters.

Nanostructured surfaces investigated by quantitative morphological studies

International Nuclear Information System (INIS)

Perani, Martina; Carapezzi, Stefania; Mutta, Geeta Rani; Cavalcoli, Daniela

2016-01-01

The morphology of different surfaces has been investigated by atomic force microscopy and quantitatively analyzed in this paper. Two different tools have been employed to this scope: the analysis of the height–height correlation function and the determination of the mean grain size, which have been combined to obtain a complete characterization of the surfaces. Different materials have been analyzed: SiO_xN_y, InGaN/GaN quantum wells and Si nanowires, grown with different techniques. Notwithstanding the presence of grain-like structures on all the samples analyzed, they present very diverse surface design, underlying that this procedure can be of general use. Our results show that the quantitative analysis of nanostructured surfaces allows us to obtain interesting information, such as grain clustering, from the comparison of the lateral correlation length and the grain size. (paper)

The Golgi localization of phosphatidylinositol transfer protein beta requires the protein kinase C-dependent phosphorylation of serine 262 and is essential for maintaining plasma membrane sphingomyelin levels.

Science.gov (United States)

van Tiel, Claudia M; Westerman, Jan; Paasman, Marten A; Hoebens, Martha M; Wirtz, Karel W A; Snoek, Gerry T

2002-06-21

Recombinant mouse phosphatidylinositol transfer protein (PI-TP)beta is a substrate for protein kinase C (PKC)-dependent phosphorylation in vitro. Based on site-directed mutagenesis and two-dimensional tryptic peptide mapping, Ser(262) was identified as the major site of phosphorylation and Ser(165) as a minor phosphorylation site. The phospholipid transfer activities of wild-type PI-TP beta and PI-TP beta(S262A) were identical, whereas PI-TP beta(S165A) was completely inactive. PKC-dependent phosphorylation of Ser(262) also had no effect on the transfer activity of PI-TP beta. To investigate the role of Ser(262) in the functioning of PI-TP beta, wtPI-TP beta and PI-TP beta(S262A) were overexpressed in NIH3T3 fibroblast cells. Two-dimensional PAGE analysis of cell lysates was used to separate PI-TP beta from its phosphorylated form. After Western blotting, wtPI-TP beta was found to be 85% phosphorylated, whereas PI-TP beta(S262A) was not phosphorylated. In the presence of the PKC inhibitor GF 109203X, the phosphorylated form of wtPI-TP beta was strongly reduced. Immunolocalization showed that wtPI-TP beta was predominantly associated with the Golgi membranes. In the presence of the PKC inhibitor, wtPI-TP beta was distributed throughout the cell similar to what was observed for PI-TP beta(S262A). In contrast to wtPI-TP beta overexpressors, cells overexpressing PI-TP beta(S262A) were unable to rapidly replenish sphingomyelin in the plasma membrane upon degradation by sphingomyelinase. This implies that PKC-dependent association with the Golgi complex is a prerequisite for PI-TP beta to express its effect on sphingomyelin metabolism.

Trilingual Code-Switching Using Quantitative Lenses: An Exploratory Study on Hokaglish

Science.gov (United States)

Gonzales, Wilkinson Daniel Wong

2016-01-01

Adopting a quantitative approach, this paper highlights findings of an exploratory study on Hokaglish, initially describing it as a trilingual code-switching phenomenon involving Hokkien, Tagalog, and English in a Filipino-Chinese enclave in Binondo, Manila, the Philippines. Departing from the (socio)linguistic landscape of the archipelagic…

Biodistribution study of [I-123] ADAM in mice brain using quantitative autoradiography

International Nuclear Information System (INIS)

Lin, K.J.; Yen, T.C.; Tzen, K.Y.; Ye, X.X.; Hwang, J.J.; Wey, S.P.; Ting, G.

2002-01-01

Aim: Autoradiography with radioluminography is a delicate method to characterize newly developed radiotracers and to apply them to pharmacological studies. Herein, we reported a biodistribution result of [I-123] ADAM (2-((2-((dimethylamino)methyl)phenyl)thio)-5- iodophenylamine) in mice brain quantitatively using imaging plates. Materials and Methods: 1mCi [I-123] ADAM was injected into male ICR mice through tail veins. Brains were removed at sequential time points ranging from 0.5hr to 4hr after injection. The whole brain was cut into 14mm thick coronal sections using a cyrotome. The sections were thaw-mounted on glass plate and apposed placed on an imaging plate with filter paper standards for 24 hours. Imaging reading was done by a Fuji FLA5000 device. Regions of interest were placed on the globus pallidus, hypothalamus, substantia nigra, raphe nuclei and cerebellum corresponding to the sterotaxic atlas, and the PSL/mm 2 values were measured. The specific binding was expressed as the ratios of (targets - cerebellum) to cerebellum. Results: Autoradiography study of brain showed that the [I-123] ADAM was accumulated at serotonin transporter rich sites, including the olfactory tubercle, globus pallidus, thalamus nuclei, hypothalamus, substantia nigra, interpeduncular nucleus, amygdala and raphe nuclei. Biodistribution of [I-123] ADAM in mice brain using quantitative autoradiography method showed a high specific binding in the substantia nigra and hypothalamus and the time-activity curve peaked at 120 min post-injection. Compatible specific binding result was achieved in the region of hypothalamus as compared with previous study by other group using conventional tissue micro-dissection method (Synapse 38:403-412, 2000). However, higher specific binding was observed in certain small brain regions including substantia nigra, raphe nuclei due to improved spatial resolution of the quantitative autoradiography technique. Conclusion: Our result showed that the

Quantitative study of FORC diagrams in thermally corrected Stoner– Wohlfarth nanoparticles systems

International Nuclear Information System (INIS)

De Biasi, E.; Curiale, J.; Zysler, R.D.

2016-01-01

The use of FORC diagrams is becoming increasingly popular among researchers devoted to magnetism and magnetic materials. However, a thorough interpretation of this kind of diagrams, in order to achieve quantitative information, requires an appropriate model of the studied system. For that reason most of the FORC studies are used for a qualitative analysis. In magnetic systems thermal fluctuations 'blur' the signatures of the anisotropy, volume and particle interactions distributions, therefore thermal effects in nanoparticles systems conspire against a proper interpretation and analysis of these diagrams. Motivated by this fact, we have quantitatively studied the degree of accuracy of the information extracted from FORC diagrams for the special case of single-domain thermal corrected Stoner– Wohlfarth (easy axes along the external field orientation) nanoparticles systems. In this work, the starting point is an analytical model that describes the behavior of a magnetic nanoparticles system as a function of field, anisotropy, temperature and measurement time. In order to study the quantitative degree of accuracy of our model, we built FORC diagrams for different archetypical cases of magnetic nanoparticles. Our results show that from the quantitative information obtained from the diagrams, under the hypotheses of the proposed model, is possible to recover the features of the original system with accuracy above 95%. This accuracy is improved at low temperatures and also it is possible to access to the anisotropy distribution directly from the FORC coercive field profile. Indeed, our simulations predict that the volume distribution plays a secondary role being the mean value and its deviation the only important parameters. Therefore it is possible to obtain an accurate result for the inversion and interaction fields despite the features of the volume distribution. - Highlights: • Quantify the degree of accuracy of the information obtained using the FORC diagrams. �

Peer support for parents of children with chronic disabling conditions: a systematic review of quantitative and qualitative studies.

Science.gov (United States)

Shilling, Val; Morris, Christopher; Thompson-Coon, Jo; Ukoumunne, Obioha; Rogers, Morwenna; Logan, Stuart

2013-07-01

To review the qualitative and quantitative evidence of the benefits of peer support for parents of children with disabling conditions in the context of health, well-being, impact on family, and economic and service implications. We comprehensively searched multiple databases. Eligible studies evaluated parent-to-parent support and reported on the psychological health and experience of giving or receiving support. There were no limits on the child's condition, study design, language, date, or setting. We sought to aggregate quantitative data; findings of qualitative studies were combined using thematic analysis. Qualitative and quantitative data were brought together in a narrative synthesis. Seventeen papers were included: nine qualitative studies, seven quantitative studies, and one mixed-methods evaluation. Four themes were identified from qualitative studies: (1) shared social identity, (2) learning from the experiences of others, (3) personal growth, and (4) supporting others. Some quantitative studies reported a positive effect of peer support on psychological health and other outcomes; however, this was not consistently confirmed. It was not possible to aggregate data across studies. No costing data were identified. Qualitative studies strongly suggest that parents perceive benefit from peer support programmes, an effect seen across different types of support and conditions. However, quantitative studies provide inconsistent evidence of positive effects. Further research should explore whether this dissonance is substantive or an artefact of how outcomes have been measured. © The Authors. Developmental Medicine & Child Neurology © 2013 Mac Keith Press.

Quantitative structure–reactivity study on sulfonation of amines, alcohols and phenols

Directory of Open Access Journals (Sweden)

Abolghasem Beheshti

2017-05-01

Full Text Available Quantitative structure–reactivity relationship (QSRR can be considered as a variant of quantitative structure property relationship (QSPR studies, where the chemical reactivity of reactants in a specified chemical reaction is related to chemical structure. As follows, the sulfonation reaction yield of 24 amines, alcohols and phenols with sulfonyl chloride was studied by QSRR. Quantum chemical calculations (b3lyp/6-31+g (d were carried out to obtain the optimized geometry. The suitable set of molecular descriptors was calculated to represent the molecular structures of compounds, such as constitutional, topological, geometrical, electrostatic and quantum-chemical descriptors. The genetic algorithm (GA was applied to select the variables that resulted in the best-fitted models. After the variable selection, multiple linear regression (MLR was utilized to construct linear QSRR models. The maximum relative error in prediction (5.26 showed that the predictive ability of the model was satisfactory and it can be used for designing similar reactants with efficient sulfonation reaction.

Results of Studying Astronomy Students’ Science Literacy, Quantitative Literacy, and Information Literacy

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Buxner, Sanlyn; Impey, Chris David; Follette, Katherine B.; Dokter, Erin F.; McCarthy, Don; Vezino, Beau; Formanek, Martin; Romine, James M.; Brock, Laci; Neiberding, Megan; Prather, Edward E.

2017-01-01

Introductory astronomy courses often serve as terminal science courses for non-science majors and present an opportunity to assess non future scientists’ attitudes towards science as well as basic scientific knowledge and scientific analysis skills that may remain unchanged after college. Through a series of studies, we have been able to evaluate students’ basic science knowledge, attitudes towards science, quantitative literacy, and informational literacy. In the Fall of 2015, we conducted a case study of a single class administering all relevant surveys to an undergraduate class of 20 students. We will present our analysis of trends of each of these studies as well as the comparison case study. In general we have found that students basic scientific knowledge has remained stable over the past quarter century. In all of our studies, there is a strong relationship between student attitudes and their science and quantitative knowledge and skills. Additionally, students’ information literacy is strongly connected to their attitudes and basic scientific knowledge. We are currently expanding these studies to include new audiences and will discuss the implications of our findings for instructors.

A Study of Cognitive Load for Enhancing Student’s Quantitative Literacy in Inquiry Lab Learning

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Nuraeni, E.; Rahman, T.; Alifiani, D. P.; Khoerunnisa, R. S.

2017-09-01

Students often find it difficult to appreciate the relevance of the role of quantitative analysis and concept attainment in the science class. This study measured student cognitive load during the inquiry lab of the respiratory system to improve quantitative literacy. Participants in this study were 40 11th graders from senior high school in Indonesia. After students learned, their feelings about the degree of mental effort that it took to complete the learning tasks were measured by 28 self-report on a 4-point Likert scale. The Task Complexity Worksheet were used to asses processing quantitative information and paper based test were applied to assess participants’ concept achievements. The results showed that inquiry instructional induced a relatively low mental effort, high processing information and high concept achievments.

Radioautographic study of binding and internalization of corticotropin-releasing factor by rat anterior pituitary corticotrophs

International Nuclear Information System (INIS)

Leroux, P.; Pelletier, G.

1984-01-01

In order to identify the anterior pituitary cell type(s) containing corticotropin-releasing factor (CRF) receptors and to study the internalization processes of this peptide by the target cells, radioautography was performed on rat anterior pituitaries removed at specific intervals (2-60 min) after intracarotid injection of [ 125 I]iodo-CRF into intact and adrenalectomized female rats. In intact animals, all corticotrophs were labeled, whereas in the adrenalectomized animals about 80% of the hypertrophied corticotrophs (adrenalectomy cells) were. In control animals injected with both iodinated CRF and an excess of unlabeled peptide, no specific reaction could be detected. The time-course study in intact animals showed that 2 min after injection most silver grains were found over or within 160 nm of the plasma membrane. At the 5-min time intervals, grains were observed both over the plasma membrane and within the cytoplasm, associated with lysosomes, and the Golgi apparatus. Fifteen minutes after injection, grains were mostly found over lysosomes and the Golgi apparatus, whereas at the longest time intervals (30 and 60 min) almost no labeling could be detected. The results obtained in this study indicate that in the anterior pituitary CRF receptors are restricted to corticotrophs (as identified by electron microscopy) and that, after binding to the plasma membrane, CRF is rapidly internalized to Golgi elements and lysosomes

[The positioning of nursing research in the academic studies: the origin and development of qualitative and quantitative studies].

Science.gov (United States)

Lu, Pei-Pei; Ting, Shing-Shiang; Chen, Mei-Ling; Tang, Woung-Ru

2005-12-01

The purpose of this study is to discuss the historical context of qualitative and quantitative research so as to explain the principle of qualitative study and examine the positioning of nursing research within academic study as a whole. This paper guides the readers towards the historical context from empirical science, discusses the influences of qualitative and quantitative research on nursing research, then investigates the nature of research paradigms, examines the positioning of nursing research, which includes the characteristics of fields such as natural science, humanity and social studies, and science, and lastly, presents the research standard proposed by Yardley in 2000. The research paradigms include Positivism, Postpositivism, Criticism, and Constructivism, which can be compared with Ontology, Epistemology, and Methodology. The nature of the paradigm is to determine the assumption of the paradigm on the basis of Ontology, Epistemology, and Methodology. The paradigm determines how the researcher views the world and decides on what to answer, how to research, and how to answer. The difference in academic environment is reflected in the long-term dialogue between qualitative and quantitative studies, as well as the standard for criticism. This paper introduces the method of evaluation of the quality of qualitative study proposed by Yardley in 2002, namely the sensitivity of the context, the promise and conscientiousness, transparency and consistency, influence and significance. The paper is intended to provide a guideline for readers in evaluating the quality of qualitative study.

Affinity for Quantitative Tools: Undergraduate Marketing Students Moving beyond Quantitative Anxiety

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Tarasi, Crina O.; Wilson, J. Holton; Puri, Cheenu; Divine, Richard L.

2013-01-01

Marketing students are known as less likely to have an affinity for the quantitative aspects of the marketing discipline. In this article, we study the reasons why this might be true and develop a parsimonious 20-item scale for measuring quantitative affinity in undergraduate marketing students. The scale was administered to a sample of business…

Quantitative studies with the gamma-camera: correction for spatial and energy distortion

International Nuclear Information System (INIS)

Soussaline, F.; Todd-Pokropek, A.E.; Raynaud, C.

1977-01-01

The gamma camera sensitivity distribution is an important source of error in quantitative studies. In addition, spatial distortion produces apparent variations in count density which degrades quantitative studies. The flood field image takes into account both effects and is influenced by the pile-up of the tail distribution. It is essential to measure separately each of these parameters. These were investigated using a point source displaced by a special scanning table with two X, Y stepping motors of 10 micron precision. The spatial distribution of the sensitivity, spatial distortion and photopeak in the field of view were measured and compared for different setting-up of the camera and PM gains. For well-tuned cameras, the sensitivity is fairly constant, while the variations appearing in the flood field image are primarily due to spatial distortion, the former more dependent than the latter on the energy window setting. This indicates why conventional flood field uniformity correction must not be applied. A correction technique to improve the results in quantitative studies has been tested using a continuously matched energy window at every point within the field. A method for correcting spatial distortion is also proposed, where, after an adequately sampled measurement of this error, a transformation can be applied to calculate the true position of events. The knowledge of the magnitude of these parameters is essential in the routine use and design of detector systems

Skeletal scintigraphy and quantitative tracer studies in metabolic bone disease

Science.gov (United States)

Fogelman, Ignac

Bone scan imaging with the current bone seeking radiopharmaceuticals, the technetium-99m labelled diphosphonates, has dramatically improved our ability to evaluate skeletal pathology. In this thesis, chapter 1 presents a review of the history of bone scanning, summarises present concepts as to the mechanism of uptake of bone seeking agents and briefly illustrates the role of bone scanning in clinical practice. In chapter 2 the applications of bone scan imaging and quantitative tracer techniques derived from the bone scan in the detection of metabolic bone disease are discussed. Since skeletal uptake of Tc-99m diphosphonate depends upon skeletal metabolism one might expect that the bone scan would be of considerable value in the assessment of metabolic bone disease. However in these disorders the whole skeleton is often diffusely involved by the metabolic process and simple visual inspection of the scan image may not reveal the uniformly increased uptake of tracer. Certain patterns of bone scan abnormality have, however, been reported in patients with primary hyperparathyroidism and renal osteo-dystrophy; the present studies extend these observations and introduce the concept of "metabolic features" which are often recognisable in conditions with generalised increased bone turnover. As an aid to systematic recognition of these features on a given bone scan image a semi-quantitative scoring system, the metabolic index, was introduced. The metabolic index allowed differentiation between various groups of patients with metabolic disorders and a control population. In addition, in a bone scan study of patients with acromegaly, it was found that the metabolic index correlated well with disease activity as measured by serum growth hormone levels. The metabolic index was, however, found to be a relatively insensitive means of identifying disease in individual patients. Patients with increased bone turnover will have an absolute increase in skeletal uptake of tracer. As a

A Quantitative Study of Oxygen as a Metabolic Regulator

Science.gov (United States)

Radhakrishnan, Krishnan; LaManna, Joseph C.; Cabrera, Marco E.

1999-01-01

An acute reduction in oxygen (O2) delivery to a tissue is generally associated with a decrease in phosphocreatine, increases in ADP, NADH/NAD, and inorganic phosphate, increased rates of glycolysis and lactate production, and reduced rates of pyruvate and fatty acid oxidation. However, given the complexity of the human bioenergetic system and its components, it is difficult to determine quantitatively how cellular metabolic processes interact to maintain ATP homeostasis during stress (e.g., hypoxia, ischemia, and exercise). Of special interest is the determination of mechanisms relating tissue oxygenation to observed metabolic responses at the tissue, organ, and whole body levels and the quantification of how changes in tissue O2 availability affect the pathways of ATP synthesis and the metabolites that control these pathways. In this study, we extend a previously developed mathematical model of human bioenergetics to provide a physicochemical framework that permits quantitative understanding of O2 as a metabolic regulator. Specifically, the enhancement permits studying the effects of variations in tissue oxygenation and in parameters controlling the rate of cellular respiration on glycolysis, lactate production, and pyruvate oxidation. The whole body is described as a bioenergetic system consisting of metabolically distinct tissue/organ subsystems that exchange materials with the blood. In order to study the dynamic response of each subsystem to stimuli, we solve the ordinary differential equations describing the temporal evolution of metabolite levels, given the initial concentrations. The solver used in the present study is the packaged code LSODE, as implemented in the NASA Lewis kinetics and sensitivity analysis code, LSENS. A major advantage of LSENS is the efficient procedures supporting systematic sensitivity analysis, which provides the basic methods for studying parameter sensitivities (i.e., changes in model behavior due to parameter variation

Immunohistochemical Markers for Quantitative Studies of Neurons and Glia in Human Neocortex

DEFF Research Database (Denmark)

Lyck, Lise; Dalmau, Ishar; Chemnitz, John

2007-01-01

Reproducible visualisation of neurons and glia in human brain is essential for quantitative studies of the cellular changes in neurological disease. However, immunohistochemistry in human brain specimens is often compromised due to prolonged fixation. To select cell-lineage specific antibodies fo...

Quantitative study on the statistical properties of fibre architecture of genuine and numerical composite microstructures

DEFF Research Database (Denmark)

Hansen, Jens Zangenberg; Brøndsted, Povl

2013-01-01

A quantitative study is carried out regarding the statistical properties of the fibre architecture found in composite laminates and that generated numerically using Statistical Representative Volume Elements (SRVE’s). The aim is to determine the reliability and consistency of SRVE’s for represent......A quantitative study is carried out regarding the statistical properties of the fibre architecture found in composite laminates and that generated numerically using Statistical Representative Volume Elements (SRVE’s). The aim is to determine the reliability and consistency of SRVE...

Outdoor blue spaces, human health and well-being: A systematic review of quantitative studies.

Science.gov (United States)

Gascon, Mireia; Zijlema, Wilma; Vert, Cristina; White, Mathew P; Nieuwenhuijsen, Mark J

2017-11-01

A growing number of quantitative studies have investigated the potential benefits of outdoor blue spaces (lakes, rivers, sea, etc) and human health, but there is not yet a systematic review synthesizing this evidence. To systematically review the current quantitative evidence on human health and well-being benefits of outdoor blue spaces. Following PRISMA guidelines for reporting systematic reviews and meta-analysis, observational and experimental quantitative studies focusing on both residential and non-residential outdoor blue space exposure were searched using specific keywords. In total 35 studies were included in the current systematic review, most of them being classified as of "good quality" (N=22). The balance of evidence suggested a positive association between greater exposure to outdoor blue spaces and both benefits to mental health and well-being (N=12 studies) and levels of physical activity (N=13 studies). The evidence of an association between outdoor blue space exposure and general health (N=6 studies), obesity (N=8 studies) and cardiovascular (N=4 studies) and related outcomes was less consistent. Although encouraging, there remains relatively few studies and a large degree of heterogeneity in terms of study design, exposure metrics and outcome measures, making synthesis difficult. Further research is needed using longitudinal research and natural experiments, preferably across a broader range of countries, to better understand the causal associations between blue spaces, health and wellbeing. Copyright © 2017 Elsevier GmbH. All rights reserved.

Algorithm of Golgi protein 73 and liver stiffness accurately diagnoses significant fibrosis in chronic HBV infection.

Science.gov (United States)

Cao, Zhujun; Li, Ziqiang; Wang, Hui; Liu, Yuhan; Xu, Yumin; Mo, Ruidong; Ren, Peipei; Chen, Lichang; Lu, Jie; Li, Hong; Zhuang, Yan; Liu, Yunye; Wang, Xiaolin; Zhao, Gangde; Tang, Weiliang; Xiang, Xiaogang; Cai, Wei; Liu, Longgen; Bao, Shisan; Xie, Qing

2017-11-01

Serum Golgi protein 73 (GP73) is a potential biomarker for fibrosis assessment. We aimed to develop an algorithm based on GP73 and liver stiffness (LS) for further improvement of accuracy for significant fibrosis in patients with antiviral-naïve chronic hepatitis B virus (HBV) infection. Diagnostic accuracy evaluation of GP73 and development of GP73-LS algorithm was performed in training cohort (n = 267) with an independent cohort (n = 133) for validation. A stepwise increasing pattern of serum GP73 was observed across fibrosis stages in patients with antiviral-naïve chronic HBV infection. Serum GP73 significantly correlated (rho = 0.48, P 73, accuracy: 63.6%). Using GP73-LS algorithm, GP73 < 63 in agreement with LS < 8.5 provided accuracy of 81.7% to excluded significant fibrosis. GP73 ≥ 63 in agreement with LS ≥ 8.5 provided accuracy of 93.3% to confirm significant fibrosis. Almost 64% or 68% of patients in the training or validation cohort could be accurately classified. Serum GP73 is a robust biomarker for significant fibrosis diagnosis. GP73-LS algorithm provided better diagnostic accuracy than currently available approaches. More than 60% antiviral naïve CHB patients could use this algorithm without resorting to liver biopsy. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Comparison of methodologic quality and study/report characteristics between quantitative clinical nursing and nursing education research articles.

Science.gov (United States)

Schneider, Barbara St Pierre; Nicholas, Jennifer; Kurrus, Jeffrey E

2013-01-01

To compare the methodologic quality and study/report characteristics between quantitative clinical nursing and nursing education research articles. The methodologic quality of quantitative nursing education research needs to advance to a higher level. Clinical research can provide guidance for nursing education to reach this level. One hundred quantitative clinical research articles from-high impact journals published in 2007 and 37 education research articles from high impact journals published in 2006 to 2007 were chosen for analysis. Clinical articles had significantly higher quality scores than education articles in three domains: number of institutions studied, type of data, and outcomes. The findings indicate three ways in which nursing education researchers can strengthen the methodologic quality of their quantitative research. With this approach, greater funding may be secured for advancing the science of nursing education.

The cyclic nucleotide gated cation channel AtCNGC10 traffics from the ER via Golgi vesicles to the plasma membrane of Arabidopsis root and leaf cells

Directory of Open Access Journals (Sweden)

Andres Marilou A

2007-09-01

Full Text Available Abstract Background The cyclic nucleotide-gated ion channels (CNGCs maintain cation homeostasis essential for a wide range of physiological processes in plant cells. However, the precise subcellular locations and trafficking of these membrane proteins are poorly understood. This is further complicated by a general deficiency of information about targeting pathways of membrane proteins in plants. To investigate CNGC trafficking and localization, we have measured Atcngc5 and Atcngc10 expression in roots and leaves, analyzed AtCNGC10-GFP fusions transiently expressed in protoplasts, and conducted immunofluorescence labeling of protoplasts and immunoelectron microscopic analysis of high pressure frozen leaves and roots. Results AtCNGC10 mRNA and protein levels were 2.5-fold higher in roots than leaves, while AtCNGC5 mRNA and protein levels were nearly equal in these tissues. The AtCNGC10-EGFP fusion was targeted to the plasma membrane in leaf protoplasts, and lightly labeled several intracellular structures. Immunofluorescence microscopy with affinity purified CNGC-specific antisera indicated that AtCNGC5 and AtCNGC10 are present in the plasma membrane of protoplasts. Immunoelectron microscopy demonstrated that AtCNGC10 was associated with the plasma membrane of mesophyll, palisade parenchyma and epidermal cells of leaves, and the meristem, columella and cap cells of roots. AtCNCG10 was also observed in the endoplasmic reticulum and Golgi cisternae and vesicles of 50–150 nm in size. Patch clamp assays of an AtCNGC10-GFP fusion expressed in HEK293 cells measured significant cation currents. Conclusion AtCNGC5 and AtCNGC10 are plasma membrane proteins. We postulate that AtCNGC10 traffics from the endoplasmic reticulum via the Golgi apparatus and associated vesicles to the plasma membrane. The presence of the cation channel, AtCNGC10, in root cap meristem cells, cell plate, and gravity-sensing columella cells, combined with the previously reported

Study on methods of quantitative analysis of the biological thin samples in EM X-ray microanalysis

International Nuclear Information System (INIS)

Zhang Detian; Zhang Xuemin; He Kun; Yang Yi; Zhang Sa; Wang Baozhen

2000-01-01

Objective: To study the methods of quantitative analysis of the biological thin samples. Methods: Hall theory was used to study the qualitative analysis, background subtraction, peel off overlap peaks; external radiation and aberrance of spectra. Results: The results of reliable qualitative analysis and precise quantitative analysis were achieved. Conclusion: The methods for analysis of the biological thin samples in EM X-ray microanalysis can be used in biomedical research

Speleogenesis, geometry, and topology of caves: A quantitative study of 3D karst conduits

Science.gov (United States)

Jouves, Johan; Viseur, Sophie; Arfib, Bruno; Baudement, Cécile; Camus, Hubert; Collon, Pauline; Guglielmi, Yves

2017-12-01

Karst systems are hierarchically spatially organized three-dimensional (3D) networks of conduits behaving as drains for groundwater flow. Recently, geostatistical approaches proposed to generate karst networks from data and parameters stemming from analogous observed karst features. Other studies have qualitatively highlighted relationships between speleogenetic processes and cave patterns. However, few studies have been performed to quantitatively define these relationships. This paper reports a quantitative study of cave geometries and topologies that takes the underlying speleogenetic processes into account. In order to study the spatial organization of caves, a 3D numerical database was built from 26 caves, corresponding to 621 km of cumulative cave passages representative of the variety of karst network patterns. The database includes 3D speleological surveys for which the speleogenetic context is known, allowing the polygenic karst networks to be divided into 48 monogenic cave samples and classified into four cave patterns: vadose branchwork (VB), water-table cave (WTC), looping cave (LC), and angular maze (AM). Eight morphometric cave descriptors were calculated, four geometrical parameters (width-height ratio, tortuosity, curvature, and vertical index) and four topological ones (degree of node connectivity, α and γ graph indices, and ramification index) respectively. The results were validated by statistical analyses (Kruskal-Wallis test and PCA). The VB patterns are clearly distinct from AM ones and from a third group including WTC and LC. A quantitative database of cave morphology characteristics is provided, depending on their speleogenetic processes. These characteristics can be used to constrain and/or validate 3D geostatistical simulations. This study shows how important it is to relate the geometry and connectivity of cave networks to recharge and flow processes. Conversely, the approach developed here provides proxies to estimate the evolution of

Subcellular distribution of swine vesicular disease virus proteins and alterations induced in infected cells: A comparative study with foot-and-mouth disease virus and vesicular stomatitis virus

International Nuclear Information System (INIS)

Martin-Acebes, Miguel A.; Gonzalez-Magaldi, Monica; Rosas, Maria F.; Borrego, Belen; Brocchi, Emiliana; Armas-Portela, Rosario; Sobrino, Francisco

2008-01-01

The intracellular distribution of swine vesicular disease virus (SVDV) proteins and the induced reorganization of endomembranes in IBRS-2 cells were analyzed. Fluorescence to new SVDV capsids appeared first upon infection, concentrated in perinuclear circular structures and colocalized to dsRNA. As in foot-and-mouth disease virus (FMDV)-infected cells, a vesicular pattern was predominantly found in later stages of SVDV capsid morphogenesis that colocalized with those of non-structural proteins 2C, 2BC and 3A. These results suggest that assembly of capsid proteins is associated to the replication complex. Confocal microscopy showed a decreased fluorescence to ER markers (calreticulin and protein disulfide isomerase), and disorganization of cis-Golgi gp74 and trans-Golgi caveolin-1 markers in SVDV- and FMDV-, but not in vesicular stomatitis virus (VSV)-infected cells. Electron microscopy of SVDV-infected cells at an early stage of infection revealed fragmented ER cisternae with expanded lumen and accumulation of large Golgi vesicles, suggesting alterations of vesicle traffic through Golgi compartments. At this early stage, FMDV induced different patterns of ER fragmentation and Golgi alterations. At later stages of SVDV cytopathology, cells showed a completely vacuolated cytoplasm containing vesicles of different sizes. Cell treatment with brefeldin A, which disrupts the Golgi complex, reduced SVDV (∼ 5 log) and VSV (∼ 4 log) titers, but did not affect FMDV growth. Thus, three viruses, which share target tissues and clinical signs in natural hosts, induce different intracellular effects in cultured cells

Comparative neuronal morphology of the cerebellar cortex in afrotherians, carnivores, cetartiodactyls, and primates

Directory of Open Access Journals (Sweden)

Bob eJacobs

2014-04-01

Full Text Available Although the basic morphological characteristics of neurons in the cerebellar cortex have been documented in several species, virtually nothing is known about the quantitative morphological characteristics of these neurons across different taxa. To that end, the present study investigated cerebellar neuronal morphology among eight different, large-brained mammalian species comprising a broad phylogenetic range: afrotherians (African elephant, Florida manatee, carnivores (Siberian tiger, clouded leopard, cetartiodactyls (humpback whale, giraffe and primates (human, common chimpanzee. Specifically, several neuron types (e.g., stellate, basket, Lugaro, Golgi, and granule neurons; N = 317 of the cerebellar cortex were stained with a modified rapid Golgi technique and quantified on a computer-assisted microscopy system. There was a 64-fold variation in brain mass across species in our sample (from clouded leopard to the elephant and a 103-fold variation in cerebellar volume. Most dendritic measures tended to increase with cerebellar volume. The cerebellar cortex in these species exhibited the trilaminate pattern common to all mammals. Morphologically, neuron types in the cerebellar cortex were generally consistent with those described in primates (Fox et al., 1967 and rodents (Palay and Chan-Palay, 1974, although there was substantial quantitative variation across species. In particular, Lugaro neurons in the elephant appeared to be disproportionately larger than those in other species. To explore potential quantitative differences in dendritic measures across species, MARSplines analyses were used to evaluate whether species could be differentiated from each other based on dendritic characteristics alone. Results of these analyses indicated that there were significant differences among all species in dendritic measures.

Central sensitization phenomena after third molar surgery: A quantitative sensory testing study

DEFF Research Database (Denmark)

Jensen, T.S.; Norholt, S.E.; Svensson, P.

2008-01-01

Background: Surgical removal of third molars may carry a risk of developing persistent orofacial pain, and central sensitization appears to play an important role in the transition from acute to chronic pain. Aim: The aim of this study was to investigate sensitization (primarily central sensitiza......Background: Surgical removal of third molars may carry a risk of developing persistent orofacial pain, and central sensitization appears to play an important role in the transition from acute to chronic pain. Aim: The aim of this study was to investigate sensitization (primarily central...... sensitization) after orofacial trauma using quantitative sensory testing (QST). Methods: A total of 32 healthy men (16 patients and 16 age-matched control subjects) underwent a battery of quantitative tests adapted to the trigeminal area at baseline and 2, 7, and 30 days following surgical removal of a lower...... impacted third molar. Results: Central sensitization for at least one week was indicated by significantly increased pain intensity evoked by intraoral repetitive pinprick and electrical stimulation (p

Quantitative background parenchymal uptake on molecular breast imaging and breast cancer risk: a case-control study.

Science.gov (United States)

Hruska, Carrie B; Geske, Jennifer R; Swanson, Tiffinee N; Mammel, Alyssa N; Lake, David S; Manduca, Armando; Conners, Amy Lynn; Whaley, Dana H; Scott, Christopher G; Carter, Rickey E; Rhodes, Deborah J; O'Connor, Michael K; Vachon, Celine M

2018-06-05

Background parenchymal uptake (BPU), which refers to the level of Tc-99m sestamibi uptake within normal fibroglandular tissue on molecular breast imaging (MBI), has been identified as a breast cancer risk factor, independent of mammographic density. Prior analyses have used subjective categories to describe BPU. We evaluate a new quantitative method for assessing BPU by testing its reproducibility, comparing quantitative results with previously established subjective BPU categories, and determining the association of quantitative BPU with breast cancer risk. Two nonradiologist operators independently performed region-of-interest analysis on MBI images viewed in conjunction with corresponding digital mammograms. Quantitative BPU was defined as a unitless ratio of the average pixel intensity (counts/pixel) within the fibroglandular tissue versus the average pixel intensity in fat. Operator agreement and the correlation of quantitative BPU measures with subjective BPU categories assessed by expert radiologists were determined. Percent density on mammograms was estimated using Cumulus. The association of quantitative BPU with breast cancer (per one unit BPU) was examined within an established case-control study of 62 incident breast cancer cases and 177 matched controls. Quantitative BPU ranged from 0.4 to 3.2 across all subjects and was on average higher in cases compared to controls (1.4 versus 1.2, p Quantitative BPU was strongly correlated with subjective BPU categories (Spearman's r = 0.59 to 0.69, p quantitative BPU measure, assessed by intraclass correlation, was 0.92 and 0.98, respectively. Quantitative BPU measures showed either no correlation or weak negative correlation with mammographic percent density. In a model adjusted for body mass index and percent density, higher quantitative BPU was associated with increased risk of breast cancer for both operators (OR = 4.0, 95% confidence interval (CI) 1.6-10.1, and 2.4, 95% CI 1.2-4.7). Quantitative

Ultra-structural study of Egyptian Buffalo oocytes before and after in ...

African Journals Online (AJOL)

The oocytes examined in this study showed normal ultra-structure of mitochondria, smooth endoplasmic reticulum (SER), zona pellucida (ZP), lipid droplets, vesicles and Golgi in the good type meanwhile, some differences and abnormalities in denuded oocytes were recorded. The most remarkable changes observed in the ...

Spectroscopic Tools for Quantitative Studies of DNA Structure and Dynamics

DEFF Research Database (Denmark)

Preus, Søren

The main objective of this thesis is to develop quantitative fluorescence-based, spectroscopic tools for probing the 3D structure and dynamics of DNA and RNA. The thesis is founded on six peer-reviewed papers covering mainly the development, characterization and use of fluorescent nucleobase...... analogues. In addition, four software packages is presented for the simulation and quantitative analysis of time-resolved and steady-state UV-Vis absorption and fluorescence experiments....

Diagnostic performance of semi-quantitative and quantitative stress CMR perfusion analysis: a meta-analysis.

Science.gov (United States)

van Dijk, R; van Assen, M; Vliegenthart, R; de Bock, G H; van der Harst, P; Oudkerk, M

2017-11-27

Stress cardiovascular magnetic resonance (CMR) perfusion imaging is a promising modality for the evaluation of coronary artery disease (CAD) due to high spatial resolution and absence of radiation. Semi-quantitative and quantitative analysis of CMR perfusion are based on signal-intensity curves produced during the first-pass of gadolinium contrast. Multiple semi-quantitative and quantitative parameters have been introduced. Diagnostic performance of these parameters varies extensively among studies and standardized protocols are lacking. This study aims to determine the diagnostic accuracy of semi- quantitative and quantitative CMR perfusion parameters, compared to multiple reference standards. Pubmed, WebOfScience, and Embase were systematically searched using predefined criteria (3272 articles). A check for duplicates was performed (1967 articles). Eligibility and relevance of the articles was determined by two reviewers using pre-defined criteria. The primary data extraction was performed independently by two researchers with the use of a predefined template. Differences in extracted data were resolved by discussion between the two researchers. The quality of the included studies was assessed using the 'Quality Assessment of Diagnostic Accuracy Studies Tool' (QUADAS-2). True positives, false positives, true negatives, and false negatives were subtracted/calculated from the articles. The principal summary measures used to assess diagnostic accuracy were sensitivity, specificity, andarea under the receiver operating curve (AUC). Data was pooled according to analysis territory, reference standard and perfusion parameter. Twenty-two articles were eligible based on the predefined study eligibility criteria. The pooled diagnostic accuracy for segment-, territory- and patient-based analyses showed good diagnostic performance with sensitivity of 0.88, 0.82, and 0.83, specificity of 0.72, 0.83, and 0.76 and AUC of 0.90, 0.84, and 0.87, respectively. In per territory

Domestic violence against women in India: A systematic review of a decade of quantitative studies.

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Kalokhe, Ameeta; Del Rio, Carlos; Dunkle, Kristin; Stephenson, Rob; Metheny, Nicholas; Paranjape, Anuradha; Sahay, Seema

2017-04-01

Domestic violence (DV) is prevalent among women in India and has been associated with poor mental and physical health. We performed a systematic review of 137 quantitative studies published in the prior decade that directly evaluated the DV experiences of Indian women to summarise the breadth of recent work and identify gaps in the literature. Among studies surveying at least two forms of abuse, a median 41% of women reported experiencing DV during their lifetime and 30% in the past year. We noted substantial inter-study variance in DV prevalence estimates, attributable in part to different study populations and settings, but also to a lack of standardisation, validation, and cultural adaptation of DV survey instruments. There was paucity of studies evaluating the DV experiences of women over age 50, residing in live-in relationships, same-sex relationships, tribal villages, and of women from the northern regions of India. Additionally, our review highlighted a gap in research evaluating the impact of DV on physical health. We conclude with a research agenda calling for additional qualitative and longitudinal quantitative studies to explore the DV correlates proposed by this quantitative literature to inform the development of a culturally tailored DV scale and prevention strategies.

Exploring the use of storytelling in quantitative research fields using a multiple case study method

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Matthews, Lori N. Hamlet

The purpose of this study was to explore the emerging use of storytelling in quantitative research fields. The focus was not on examining storytelling in research, but rather how stories are used in various ways within the social context of quantitative research environments. In-depth interviews were conducted with seven professionals who had experience using storytelling in their work and my personal experience with the subject matter was also used as a source of data according to the notion of researcher-as-instrument. This study is qualitative in nature and is guided by two supporting theoretical frameworks, the sociological perspective and narrative inquiry. A multiple case study methodology was used to gain insight about why participants decided to use stories or storytelling in a quantitative research environment that may not be traditionally open to such methods. This study also attempted to identify how storytelling can strengthen or supplement existing research, as well as what value stories can provide to the practice of research in general. Five thematic findings emerged from the data and were grouped under two headings, "Experiencing Research" and "Story Work." The themes were found to be consistent with four main theoretical functions of storytelling identified in existing scholarly literature: (a) sense-making; (b) meaning-making; (c) culture; and (d) communal function. The five thematic themes that emerged from this study and were consistent with the existing literature include: (a) social context; (b) quantitative versus qualitative; (c) we think and learn in terms of stories; (d) stories tie experiences together; and (e) making sense and meaning. Recommendations are offered in the form of implications for various social contexts and topics for further research are presented as well.

Cadmium induced changes in cell organelles: An ultrastructural study using cadmium sensitive and resistant muntjac fibroblast cell lines

Energy Technology Data Exchange (ETDEWEB)

Ord, M.J.; Chibber, R.; Bouffler, S.D.

1988-09-01

A detailed electron microscopy study of cadmium sensitive and resistant muntjac fibroblast cell lines has identified a wide range of intracellular damage following exposure to cadmium. Damaged organelles included cell membrane, mitochondria, Golgi cisternae and tubular network, chromatin, nucleoli, microfilaments and ribosomes. Although cell membrane damage was generally the earliest indication of adverse cadmium action, particularly with continuous cadmium exposures, cells could tolerate extensive membrane loss. Mitochondrial distortion and some damage to Golgi was also tolerated. The turning point at which cadmium became lethal was generally marked by a cascade of events which included damage to both nuclear and cytoplasmic components. These results for fibroblasts are discussed and compared with damage reported in other types of cells.

SPECT myocardial blood flow quantitation toward clinical use: a comparative study with {sup 13}N-Ammonia PET myocardial blood flow quantitation

Energy Technology Data Exchange (ETDEWEB)

Hsu, Bailing [University of Missouri-Columbia, Nuclear Science and Engineering Institute, Columbia, Missouri (United States); Hu, Lien-Hsin; Yang, Bang-Hung; Ting, Chien-Hsin; Huang, Wen-Sheng [Taipei Veterans General Hospital, Department of Nuclear Medicine, Taipei (China); Chen, Lung-Ching [Shin Kong Wu-Ho Su Memorial Hospital, Division of Cardiology, Taipei (China); Chen, Yen-Kung [Shin Kong Wu-Ho Su Memorial Hospital, Department of Nuclear Medicine, Taipei (China); Hung, Guang-Uei [Chang Bing Show Chwan Memorial Hospital, Department of Nuclear Medicine, Changhua (China); Wu, Tao-Cheng [National Yang-Ming University, Cardiovascular Research Center, Taipei (China)

2017-01-15

The aim of this study was to evaluate the accuracy of myocardial blood flow (MBF) quantitation of {sup 99m}Tc-Sestamibi (MIBI) single photon emission computed tomography (SPECT) compared with {sup 13}N-Ammonia (NH3) position emission tomography (PET) on the same cohorts. Recent advances of SPECT technologies have been applied to develop MBF quantitation as a promising tool to diagnose coronary artery disease (CAD) for areas where PET MBF quantitation is not available. However, whether the SPECT approach can achieve the same level of accuracy as the PET approach for clinical use still needs further investigations. Twelve healthy volunteers (HVT) and 16 clinical patients with CAD received both MIBI SPECT and NH3 PET flow scans. Dynamic SPECT images acquired with high temporary resolution were fully corrected for physical factors and processed to quantify K1 using the standard compartmental modeling. Human MIBI tracer extraction fraction (EF) was determined by comparing MIBI K1 and NH3 flow on the HVT group and then used to convert flow values from K1 for all subjects. MIBI and NH3 flow values were systematically compared to validate the SPECT approach. The human MIBI EF was determined as [1.0-0.816*exp(-0.267/MBF)]. Global and regional MBF and myocardial flow reserve (MFR) of MIBI SPECT and NH3 PET were highly correlated for all subjects (global R{sup 2}: MBF = 0.92, MFR = 0.78; regional R{sup 2}: MBF ≥ 0.88, MFR ≥ 0.71). No significant differences for rest flow, stress flow, and MFR between these two approaches were observed (All p ≥ 0.088). Bland-Altman plots overall revealed small bias between MIBI SPECT and NH3 PET (global: ΔMBF = -0.03Lml/min/g, ΔMFR = 0.07; regional: ΔMBF = -0.07 - 0.06, ΔMFR = -0.02 - 0.22). Quantitation with SPECT technologies can be accurate to measure myocardial blood flow as PET quantitation while comprehensive imaging factors of SPECT to derive the variability between these two approaches were fully addressed and corrected

SPECT myocardial blood flow quantitation toward clinical use: a comparative study with "1"3N-Ammonia PET myocardial blood flow quantitation

International Nuclear Information System (INIS)

Hsu, Bailing; Hu, Lien-Hsin; Yang, Bang-Hung; Ting, Chien-Hsin; Huang, Wen-Sheng; Chen, Lung-Ching; Chen, Yen-Kung; Hung, Guang-Uei; Wu, Tao-Cheng

2017-01-01

The aim of this study was to evaluate the accuracy of myocardial blood flow (MBF) quantitation of "9"9"mTc-Sestamibi (MIBI) single photon emission computed tomography (SPECT) compared with "1"3N-Ammonia (NH3) position emission tomography (PET) on the same cohorts. Recent advances of SPECT technologies have been applied to develop MBF quantitation as a promising tool to diagnose coronary artery disease (CAD) for areas where PET MBF quantitation is not available. However, whether the SPECT approach can achieve the same level of accuracy as the PET approach for clinical use still needs further investigations. Twelve healthy volunteers (HVT) and 16 clinical patients with CAD received both MIBI SPECT and NH3 PET flow scans. Dynamic SPECT images acquired with high temporary resolution were fully corrected for physical factors and processed to quantify K1 using the standard compartmental modeling. Human MIBI tracer extraction fraction (EF) was determined by comparing MIBI K1 and NH3 flow on the HVT group and then used to convert flow values from K1 for all subjects. MIBI and NH3 flow values were systematically compared to validate the SPECT approach. The human MIBI EF was determined as [1.0-0.816*exp(-0.267/MBF)]. Global and regional MBF and myocardial flow reserve (MFR) of MIBI SPECT and NH3 PET were highly correlated for all subjects (global R"2: MBF = 0.92, MFR = 0.78; regional R"2: MBF ≥ 0.88, MFR ≥ 0.71). No significant differences for rest flow, stress flow, and MFR between these two approaches were observed (All p ≥ 0.088). Bland-Altman plots overall revealed small bias between MIBI SPECT and NH3 PET (global: ΔMBF = -0.03Lml/min/g, ΔMFR = 0.07; regional: ΔMBF = -0.07 - 0.06, ΔMFR = -0.02 - 0.22). Quantitation with SPECT technologies can be accurate to measure myocardial blood flow as PET quantitation while comprehensive imaging factors of SPECT to derive the variability between these two approaches were fully addressed and corrected. (orig.)

Characterization of yeast extracellular vesicles: evidence for the participation of different pathways of cellular traffic in vesicle biogenesis.

Directory of Open Access Journals (Sweden)

Débora L Oliveira

2010-06-01

Full Text Available Extracellular vesicles in yeast cells are involved in the molecular traffic across the cell wall. In yeast pathogens, these vesicles have been implicated in the transport of proteins, lipids, polysaccharide and pigments to the extracellular space. Cellular pathways required for the biogenesis of yeast extracellular vesicles are largely unknown.We characterized extracellular vesicle production in wild type (WT and mutant strains of the model yeast Saccharomyces cerevisiae using transmission electron microscopy in combination with light scattering analysis, lipid extraction and proteomics. WT cells and mutants with defective expression of Sec4p, a secretory vesicle-associated Rab GTPase essential for Golgi-derived exocytosis, or Snf7p, which is involved in multivesicular body (MVB formation, were analyzed in parallel. Bilayered vesicles with diameters at the 100-300 nm range were found in extracellular fractions from yeast cultures. Proteomic analysis of vesicular fractions from the cells aforementioned and additional mutants with defects in conventional secretion pathways (sec1-1, fusion of Golgi-derived exocytic vesicles with the plasma membrane; bos1-1, vesicle targeting to the Golgi complex or MVB functionality (vps23, late endosomal trafficking revealed a complex and interrelated protein collection. Semi-quantitative analysis of protein abundance revealed that mutations in both MVB- and Golgi-derived pathways affected the composition of yeast extracellular vesicles, but none abrogated vesicle production. Lipid analysis revealed that mutants with defects in Golgi-related components of the secretory pathway had slower vesicle release kinetics, as inferred from intracellular accumulation of sterols and reduced detection of these lipids in vesicle fractions in comparison with WT cells.Our results suggest that both conventional and unconventional pathways of secretion are required for biogenesis of extracellular vesicles, which demonstrate the

The Relationship between Stress, Coping Style, and Academic Satisfaction: A Quantitative Study

Science.gov (United States)

Hodge-Windover, Sheila T.

2017-01-01

College students experience a great deal of stress, which is associated with poor health and poor levels of academic satisfaction which can lead to low retention. The purpose of this quantitative correlational study was to investigate how stress and coping style predict academic satisfaction and understand how and if coping style moderates the…

Sphingomyelin synthases regulate protein trafficking and secretion.

Directory of Open Access Journals (Sweden)

Marimuthu Subathra

Full Text Available Sphingomyelin synthases (SMS1 and 2 represent a class of enzymes that transfer a phosphocholine moiety from phosphatidylcholine onto ceramide thus producing sphingomyelin and diacylglycerol (DAG. SMS1 localizes at the Golgi while SMS2 localizes both at the Golgi and the plasma membrane. Previous studies from our laboratory showed that modulation of SMS1 and, to a lesser extent, of SMS2 affected the formation of DAG at the Golgi apparatus. As a consequence, down-regulation of SMS1 and SMS2 reduced the localization of the DAG-binding protein, protein kinase D (PKD, to the Golgi. Since PKD recruitment to the Golgi has been implicated in cellular secretion through the trans golgi network (TGN, the effect of down-regulation of SMSs on TGN-to-plasma membrane trafficking was studied. Down regulation of either SMS1 or SMS2 significantly retarded trafficking of the reporter protein vesicular stomatitis virus G protein tagged with GFP (VSVG-GFP from the TGN to the cell surface. Inhibition of SMSs also induced tubular protrusions from the trans Golgi network reminiscent of inhibited TGN membrane fission. Since a recent study demonstrated the requirement of PKD activity for insulin secretion in beta cells, we tested the function of SMS in this model. Inhibition of SMS significantly reduced insulin secretion in rat INS-1 cells. Taken together these results provide the first direct evidence that both enzymes (SMS1 and 2 are capable of regulating TGN-mediated protein trafficking and secretion, functions that are compatible with PKD being a down-stream target for SMSs in the Golgi.

Quantitative habitability.

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Shock, Everett L; Holland, Melanie E

2007-12-01

A framework is proposed for a quantitative approach to studying habitability. Considerations of environmental supply and organismal demand of energy lead to the conclusions that power units are most appropriate and that the units for habitability become watts per organism. Extreme and plush environments are revealed to be on a habitability continuum, and extreme environments can be quantified as those where power supply only barely exceeds demand. Strategies for laboratory and field experiments are outlined that would quantify power supplies, power demands, and habitability. An example involving a comparison of various metabolisms pursued by halophiles is shown to be well on the way to a quantitative habitability analysis.

Quantification of myelin in children using multiparametric quantitative MRI: a pilot study

International Nuclear Information System (INIS)

Kim, Hyun Gi; Choi, Jin Wook; Moon, Won-Jin; Han, JinJoo

2017-01-01

The purpose of this study was to evaluate the usefulness of multiparametric quantitative MRI for myelination quantification in children. We examined 22 children (age 0-14 years) with multiparametric quantitative MRI. The total volume of myelin partial volume (Msum), the percentage of Msum within the whole brain parenchyma (Mbpv), and the percentage of Msum within the intracranial volume (Micv) were obtained. Four developmental models of myelin maturation (the logarithmic, logistic, Gompertz, and modified Gompertz models) were examined to find the most representative model of the three parameters. We acquired myelin partial volume values in different brain regions and assessed the goodness of fit for the models. The ranges of Msum, Mbpv, and Micv were 0.8-160.9 ml, 0.2-13%, and 0.0-11.6%, respectively. The Gompertz model was the best fit for the three parameters. For developmental model analysis of myelin partial volume in each brain region, the Gompertz model was the best-fit model for pons (R"2 = 74.6%), middle cerebeller peduncle (R"2 = 76.4%), putamen (R"2 = 95.8%), and centrum semiovale (R"2 = 77.7%). The logistic model was the best-fit model for the genu and splenium of the corpus callosum (R"2 = 79.7-93.6%), thalamus (R"2 = 81.7%), and frontal, parietal, temporal, and occipital white matter (R"2 = 92.5-96.5%). Multiparametric quantitative MRI depicts the normal developmental pattern of myelination in children. It is a potential tool for research studies on pediatric brain development evaluation. (orig.)

Quantification of myelin in children using multiparametric quantitative MRI: a pilot study

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyun Gi; Choi, Jin Wook [Ajou University School of Medicine, Ajou University Medical Center, Department of Radiology, Suwon (Korea, Republic of); Moon, Won-Jin [Konkuk University Hospital, Konkuk University School of Medicine, Department of Radiology, Seoul (Korea, Republic of); Han, JinJoo [Ajou University School of Medicine, Office of Biostatistics, Department of Humanities and Social Medicine, Suwon (Korea, Republic of)

2017-10-15

The purpose of this study was to evaluate the usefulness of multiparametric quantitative MRI for myelination quantification in children. We examined 22 children (age 0-14 years) with multiparametric quantitative MRI. The total volume of myelin partial volume (Msum), the percentage of Msum within the whole brain parenchyma (Mbpv), and the percentage of Msum within the intracranial volume (Micv) were obtained. Four developmental models of myelin maturation (the logarithmic, logistic, Gompertz, and modified Gompertz models) were examined to find the most representative model of the three parameters. We acquired myelin partial volume values in different brain regions and assessed the goodness of fit for the models. The ranges of Msum, Mbpv, and Micv were 0.8-160.9 ml, 0.2-13%, and 0.0-11.6%, respectively. The Gompertz model was the best fit for the three parameters. For developmental model analysis of myelin partial volume in each brain region, the Gompertz model was the best-fit model for pons (R{sup 2} = 74.6%), middle cerebeller peduncle (R{sup 2} = 76.4%), putamen (R{sup 2} = 95.8%), and centrum semiovale (R{sup 2} = 77.7%). The logistic model was the best-fit model for the genu and splenium of the corpus callosum (R{sup 2} = 79.7-93.6%), thalamus (R{sup 2} = 81.7%), and frontal, parietal, temporal, and occipital white matter (R{sup 2} = 92.5-96.5%). Multiparametric quantitative MRI depicts the normal developmental pattern of myelination in children. It is a potential tool for research studies on pediatric brain development evaluation. (orig.)

Managing the Public Sector Research and Development Portfolio Selection Process: A Case Study of Quantitative Selection and Optimization

Science.gov (United States)

2016-09-01

PUBLIC SECTOR RESEARCH & DEVELOPMENT PORTFOLIO SELECTION PROCESS: A CASE STUDY OF QUANTITATIVE SELECTION AND OPTIMIZATION by Jason A. Schwartz...PUBLIC SECTOR RESEARCH & DEVELOPMENT PORTFOLIO SELECTION PROCESS: A CASE STUDY OF QUANTITATIVE SELECTION AND OPTIMIZATION 5. FUNDING NUMBERS 6...describing how public sector organizations can implement a research and development (R&D) portfolio optimization strategy to maximize the cost

Preparing Tomorrow's Administrators: A Quantitative Correlation Study of the Relationship between Emotional Intelligence and Effective Leadership Practices

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May-Vollmar, Kelly

2017-01-01

Purpose: The purpose of this quantitative correlation study was to identify whether there is a relationship between emotional intelligence and effective leadership practices, specifically with school administrators in Southern California K-12 public schools. Methods: This study was conducted using a quantitative descriptive design, correlation…

ABRF-PRG07: advanced quantitative proteomics study.

Science.gov (United States)

Falick, Arnold M; Lane, William S; Lilley, Kathryn S; MacCoss, Michael J; Phinney, Brett S; Sherman, Nicholas E; Weintraub, Susan T; Witkowska, H Ewa; Yates, Nathan A

2011-04-01

A major challenge for core facilities is determining quantitative protein differences across complex biological samples. Although there are numerous techniques in the literature for relative and absolute protein quantification, the majority is nonroutine and can be challenging to carry out effectively. There are few studies comparing these technologies in terms of their reproducibility, accuracy, and precision, and no studies to date deal with performance across multiple laboratories with varied levels of expertise. Here, we describe an Association of Biomolecular Resource Facilities (ABRF) Proteomics Research Group (PRG) study based on samples composed of a complex protein mixture into which 12 known proteins were added at varying but defined ratios. All of the proteins were present at the same concentration in each of three tubes that were provided. The primary goal of this study was to allow each laboratory to evaluate its capabilities and approaches with regard to: detection and identification of proteins spiked into samples that also contain complex mixtures of background proteins and determination of relative quantities of the spiked proteins. The results returned by 43 participants were compiled by the PRG, which also collected information about the strategies used to assess overall performance and as an aid to development of optimized protocols for the methodologies used. The most accurate results were generally reported by the most experienced laboratories. Among laboratories that used the same technique, values that were closer to the expected ratio were obtained by more experienced groups.

Quantitative data study on energy innovation; Kwantitatief data onderzoek Energie-innovaties

Energy Technology Data Exchange (ETDEWEB)

Clocquet, R. [DHV, Eindhoven (Netherlands)

2012-05-15

NL Agency desires, on the basis of the study 'State of the Land energy innovation of the built environment', to gain insight in the market, in particular where it concerns the process approach towards innovation. The study consists of a quantitative and a qualitative part [Dutch] Agentschap NL wil aan de hand van het onderzoek Stand van het Land energie-innovaties gebouwde omgeving een beeld geven waar de markt staat op het gebied van met name de procesaanpak ten behoeve van innovatie. Het onderzoek bestaat uit een kwantitatief en een kwalitatief deel.

Quantitative imaging of the human upper airway: instrument design and clinical studies

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Leigh, M. S.; Armstrong, J. J.; Paduch, A.; Sampson, D. D.; Walsh, J. H.; Hillman, D. R.; Eastwood, P. R.

2006-08-01

Imaging of the human upper airway is widely used in medicine, in both clinical practice and research. Common imaging modalities include video endoscopy, X-ray CT, and MRI. However, no current modality is both quantitative and safe to use for extended periods of time. Such a capability would be particularly valuable for sleep research, which is inherently reliant on long observation sessions. We have developed an instrument capable of quantitative imaging of the human upper airway, based on endoscopic optical coherence tomography. There are no dose limits for optical techniques, and the minimally invasive imaging probe is safe for use in overnight studies. We report on the design of the instrument and its use in preliminary clinical studies, and we present results from a range of initial experiments. The experiments show that the instrument is capable of imaging during sleep, and that it can record dynamic changes in airway size and shape. This information is useful for research into sleep disorders, and potentially for clinical diagnosis and therapies.

ADVANCING THE STUDY OF VIOLENCE AGAINST WOMEN USING MIXED METHODS: INTEGRATING QUALITATIVE METHODS INTO A QUANTITATIVE RESEARCH PROGRAM

Science.gov (United States)

Testa, Maria; Livingston, Jennifer A.; VanZile-Tamsen, Carol

2011-01-01

A mixed methods approach, combining quantitative with qualitative data methods and analysis, offers a promising means of advancing the study of violence. Integrating semi-structured interviews and qualitative analysis into a quantitative program of research on women’s sexual victimization has resulted in valuable scientific insight and generation of novel hypotheses for testing. This mixed methods approach is described and recommendations for integrating qualitative data into quantitative research are provided. PMID:21307032

Adrenergic regulation of cytoplasmic structures related to secretory processes in pig pinealocytes-an ultrastructural, quantitative study.

Science.gov (United States)

Przybylska-Gornowicz, Barbara; Lewczuk, Bogdan; Ziółkowska, Natalia; Prusik, Magdalena

2017-10-01

Two structures, considered as secretory in nature, are present in the pinealocytes in of the domestic pig show the presence of two structures, which are considered as secretory in nature - the dense core vesicles (DCV) and the membrane bounded (dense) bodies (MBB). The latter are extremely numerous in pig pinealocytes (they occupy 6-20% of the cytoplasm), and the number of MBB changes under different physiological and experimental conditions. Norepinephrine is the main neurotransmitter that regulates the secretion of pineal melatonin. The present study was carried out to 1) clarify whether the DCV and their source - the Golgi apparatus (GA) - as well as the MBB are controlled by norepinephrine, 2) determine the effect of adrenergic stimulation on these structures, and 3) identify the receptors involved in the regulation of these structures. The studies were performed using a static organ culture of pig pineal explants. The explants were incubated in a control medium between 08:00 and 20:00 and in a medium with 10μM norepinephrine or alpha- or beta-adrenoceptor agonists between 20:00 and 08:00 on five consecutive days. The tissues were subsequently prepared for ultrastructural analysis. The results distinctly showed that the DCV, GA and MBB in pig pinealocytes are under adrenergic control. The stimulation of the beta-adrenoceptors resulted in an increase in the numerical density of the DCV and a decrease in the relative volume of the GA in the perikarya, while the incubation with agonists of the alpha1-adrenoceptors was ineffective. The relative volume of the MBB in the perikarya significantly decreased after treatment with both beta-agonists and alpha1-agonists, which suggested the involvement of two types of adrenoceptors in the regulation of these structures. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of colchicine on the transport of precursor enamel protein in secretory ameloblasts studied by 3H-proline radioautography in vitro

International Nuclear Information System (INIS)

Matsuo, S.; Takano, Y.; Wakisaka, S.; Ichikawa, H.; Nishikawa, S.; Akai, M.

1988-01-01

The incorporation of 3H-proline into the secretory ameloblasts of rat molar tooth germs cultured with or without colchicine was studied by light and electron microscope radioautography to determine the function of microtubules in the transport of precursor enamel protein from the rough-surfaced endoplasmic reticulum (rER) to the Golgi cisternae. The grain counts over the transitional vesicles, which accumulated in various cellular regions with colchicine treatment, continued to increase with chase time, unlike in controls. At 30 and 90 min chase, these counts were significantly higher than in controls. Moreover, the total grain count over the organelles (rER, pale granules, and transitional vesicles), which are positioned before the Golgi cisternae in the synthetic pathway, maintained a significantly higher level at 90 min chase in colchicine-treated tooth germs than in controls. The transport of synthesized protein to the Golgi cisternae via transitional vesicles was suppressed in colchicine-treated tooth germs. Some grains appeared with time over pale granular materials that appeared in the intercellular spaces of secretory ameloblasts with colchicine treatment. However, at each chase period, the grain count over pale granular materials was not so high as the count over the enamel in control. The present results indicate that colchicine affects the transport of newly synthesized protein from the rER to the Golgi cisterna via transitional vesicles, probably by interfering with the oriented transport related to microtubular function. It is suggested that the microtubular system may be concerned with the movement of the transitional vesicles

Meta-Analysis of Results from Quantitative Trait Loci Mapping Studies on Pig Chromosome 4

NARCIS (Netherlands)

Moraes Silva, De K.M.; Bastiaansen, J.W.M.; Knol, E.F.; Merks, J.W.M.; Lopes, P.S.; Guimaraes, R.M.; Arendonk, van J.A.M.

2011-01-01

Meta-analysis of results from multiple studies could lead to more precise quantitative trait loci (QTL) position estimates compared to the individual experiments. As the raw data from many different studies are not readily available, the use of results from published articles may be helpful. In this

Human Ubc9 is involved in intracellular HIV-1 Env stability after trafficking out of the trans-Golgi network in a Gag dependent manner.

Directory of Open Access Journals (Sweden)

Christopher R Bohl

Full Text Available The cellular E2 Sumo conjugase, Ubc9 interacts with HIV-1 Gag, and is important for the assembly of infectious HIV-1 virions. In the previous study we demonstrated that in the absence of Ubc9, a defect in virion assembly was associated with decreased levels of mature intracellular Envelope (Env that affected Env incorporation into virions and virion infectivity. We have further characterized the effect of Ubc9 knockdown on HIV Env processing and assembly. We found that gp160 stability in the endoplasmic reticulum (ER and its trafficking to the trans-Golgi network (TGN were unaffected, indicating that the decreased intracellular mature Env levels in Ubc9-depleted cells were due to a selective degradation of mature Env gp120 after cleavage from gp160 and trafficked out of the TGN. Decreased levels of Gag and mature Env were found to be associated with the plasma membrane and lipid rafts, which suggest that these viral proteins were not trafficked correctly to the assembly site. Intracellular gp120 were partially rescued when treated with a combination of lysosome inhibitors. Taken together our results suggest that in the absence of Ubc9, gp120 is preferentially degraded in the lysosomes likely before trafficking to assembly sites leading to the production of defective virions. This study provides further insight in the processing and packaging of the HIV-1 gp120 into mature HIV-1 virions.

Prospective Middle-School Mathematics Teachers' Quantitative Reasoning and Their Support for Students' Quantitative Reasoning

Science.gov (United States)

Kabael, Tangul; Akin, Ayca

2018-01-01

The aim of this research is to examine prospective mathematics teachers' quantitative reasoning, their support for students' quantitative reasoning and the relationship between them, if any. The teaching experiment was used as the research method in this qualitatively designed study. The data of the study were collected through a series of…

Patient expectations of treatment for back pain - A systematic review of qualitative and quantitative studies

NARCIS (Netherlands)

Verbeek, Jos; Sengers, Marie-José; Riemens, Linda; Haafkens, Joke

2004-01-01

Study Design. A systematic review of qualitative and quantitative studies. Objectives. To summarize evidence from studies among patients with low back pain on their expectations and satisfaction with treatment as part of practice guideline development. Summary of Background Data. Patients are often

Quantitative study of late injury in the irradiated mouse lung using computer graphics

International Nuclear Information System (INIS)

Tanabe, Masahiro; Furuse, Takeshi; Rapachietta, D.R.; Kallman, R.F.

1990-01-01

It is reported that quantitative histological analysis using current imaging technology and computer graphics is useful in studying late injury in the irradiated lung (with and without added chemotherapy), and that it correlated closely with results of the functional breathing rate test. (author). 7 refs.; 1 fig

Infusion of Quantitative and Statistical Concepts into Biology Courses Does Not Improve Quantitative Literacy

Science.gov (United States)

Beck, Christopher W.

2018-01-01

Multiple national reports have pushed for the integration of quantitative concepts into the context of disciplinary science courses. The aim of this study was to evaluate the quantitative and statistical literacy of biology students and explore learning gains when those skills were taught implicitly in the context of biology. I examined gains in…

Quantitative Susceptibility Mapping Indicates a Disturbed Brain Iron Homeostasis in Neuromyelitis Optica ? A Pilot Study

OpenAIRE

Doring, Thomas Martin; Granado, Vanessa; Rueda, Fernanda; Deistung, Andreas; Reichenbach, Juergen R.; Tukamoto, Gustavo; Gasparetto, Emerson Leandro; Schweser, Ferdinand

2016-01-01

Dysregulation of brain iron homeostasis is a hallmark of many neurodegenerative diseases and can be associated with oxidative stress. The objective of this study was to investigate brain iron in patients with Neuromyelitis Optica (NMO) using quantitative susceptibility mapping (QSM), a quantitative iron-sensitive MRI technique. 12 clinically confirmed NMO patients (6 female and 6 male; age 35.4y±14.2y) and 12 age- and sex-matched healthy controls (7 female and 5 male; age 33.9±11.3y) underwen...

Test-retest studies in quantitative sensory testing

DEFF Research Database (Denmark)

Werner, M U; Petersen, M A; Bischoff, J M

2013-01-01

Quantitative sensory testing (QST) investigates the graded psychophysical response to controlled thermal, mechanical, electrical or chemical stimuli, allowing quantification of clinically relevant perception and pain thresholds. The methods are ubiquitously used in experimental and clinical pain...... research, and therefore, the need for uniform assessment procedures has been emphasised. However, varying consistency and transparency in the statistical methodology seem to occur in the QST literature. Sixteen publications, evaluating aspects of QST variability, from 2010 to 2012, were critically reviewed...

Quantitative laser diagnostic and modeling study of C2 and CH chemistry in combustion.

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Köhler, Markus; Brockhinke, Andreas; Braun-Unkhoff, Marina; Kohse-Höinghaus, Katharina

2010-04-15

Quantitative concentration measurements of CH and C(2) have been performed in laminar, premixed, flat flames of propene and cyclopentene with varying stoichiometry. A combination of cavity ring-down (CRD) spectroscopy and laser-induced fluorescence (LIF) was used to enable sensitive detection of these species with high spatial resolution. Previously, CH and C(2) chemistry had been studied, predominantly in methane flames, to understand potential correlations of their formation and consumption. For flames of larger hydrocarbon fuels, however, quantitative information on these small intermediates is scarce, especially under fuel-rich conditions. Also, the combustion chemistry of C(2) in particular has not been studied in detail, and although it has often been observed, its role in potential build-up reactions of higher hydrocarbon species is not well understood. The quantitative measurements performed here are the first to detect both species with good spatial resolution and high sensitivity in the same experiment in flames of C(3) and C(5) fuels. The experimental profiles were compared with results of combustion modeling to reveal details of the formation and consumption of these important combustion molecules, and the investigation was devoted to assist the further understanding of the role of C(2) and of its potential chemical interdependences with CH and other small radicals.

Quantitative study of undersampled recoverability for sparse images in computed tomography

DEFF Research Database (Denmark)

Jørgensen, Jakob Heide; Sidky, Emil Y.; Hansen, Per Christian

2012-01-01

on artificial random sampling patterns. We establish quantitatively an average-case relation between image sparsity and sufficient number of measurements for recovery, and we show that the transition from non-recovery to recovery is sharp within well-defined classes of simple and semi-realistic test images....... The specific behavior depends on the type of image, but the same quantitative relation holds independently of image size....

Fine structure and synaptic organization of the mesencephalic trigeminal nucleus of the cat: a quantitative electron microscopic study.

Science.gov (United States)

Lazarov, N

1996-01-01

The ultrastructure and synaptic organization of the mesencephalic trigeminal nucleus (MTN) were studied in adult cats by transmission electron microscopy and more precisely quantified with an automated image analysis system. Two subpopulations of MTN neurons were identified within the nucleus: large spherical or ovoid (pseudo)unipolar cells amounted to about 60% of the total population that resemble typical primary sensory neurons and small multipolar neurons (estimated 40%), some of which are possibly interneurons. By electron microscopy, most neurons in the MTN proved to have a rich cytoplasm in the perikaryon with abundant rough endoplasmic reticulum, a large number of free ribosomes and polysomes, also well-developed Golgi complex, and numerous mitochondria and neurofilaments indicating a high rate of protein synthesis and axonal transport in these cells. Three types of synaptic contacts were observed in the MTN: axodendritic, axosomatic and axospinic of both symmetric and asymmetric morphology. Most of them (almost 90%) were axodendritic and axodendritic spine. Approximately 70% of axon terminals contained small round vesicles (S-type boutons) whereas the other 30% belonged to the P-type boutons filled with a pleomorphic vesicle population. Axosomatic synapses were comparatively rare accounting for 10% of the total. About two-third of them were of S-type and almost 25% of the remaining third were F-type in which flat synaptic vesicles could be seen, and less than 10% were P- and G-types with granular vesicles.

Studying learning in the healthcare setting: the potential of quantitative diary methods

NARCIS (Netherlands)

Ciere, Yvette; Jaarsma, Debbie; Visser, Annemieke; Sanderman, Robbert; Snippe, Evelien; Fleer, Joke

2015-01-01

Quantitative diary methods are longitudinal approaches that involve the repeated measurement of aspects of peoples’ experience of daily life. In this article, we outline the main characteristics and applications of quantitative diary methods and discuss how their use may further research in the

Physiotherapists' beliefs and attitudes influence clinical practice in chronic low back pain: a systematic review of quantitative and qualitative studies.

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Gardner, Tania; Refshauge, Kathryn; Smith, Lorraine; McAuley, James; Hübscher, Markus; Goodall, Stephen

2017-07-01

What influence do physiotherapists' beliefs and attitudes about chronic low back pain have on their clinical management of people with chronic low back pain? Systematic review with data from quantitative and qualitative studies. Quantitative and qualitative studies were included if they investigated an association between physiotherapists' attitudes and beliefs about chronic low back pain and their clinical management of people with chronic low back pain. Five quantitative and five qualitative studies were included. Quantitative studies used measures of treatment orientation and fear avoidance to indicate physiotherapists' beliefs and attitudes about chronic low back pain. Quantitative studies showed that a higher biomedical orientation score (indicating a belief that pain and disability result from a specific structural impairment, and treatment is selected to address that impairment) was associated with: advice to delay return to work, advice to delay return to activity, and a belief that return to work or activity is a threat to the patient. Physiotherapists' fear avoidance scores were positively correlated with: increased certification of sick leave, advice to avoid return to work, and advice to avoid return to normal activity. Qualitative studies revealed two main themes attributed to beliefs and attitudes of physiotherapists who have a relationship to their management of chronic low back pain: treatment orientation and patient factors. Both quantitative and qualitative studies showed a relationship between treatment orientation and clinical practice. The inclusion of qualitative studies captured the influence of patient factors in clinical practice in chronic low back pain. There is a need to recognise that both beliefs and attitudes regarding treatment orientation of physiotherapists, and therapist-patient factors need to be considered when introducing new clinical practice models, so that the adoption of new clinical practice is maximised. [Gardner T

The relationship between international trade and non-nutritional health outcomes: A systematic review of quantitative studies.

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Burns, Darren K; Jones, Andrew P; Suhrcke, Marc

2016-03-01

Markets throughout the world have been reducing barriers to international trade and investment in recent years. The resulting increases in levels of international trade and investment have subsequently generated research interest into the potential population health impact. We present a systematic review of quantitative studies investigating the relationship between international trade, foreign direct investment and non-nutritional health outcomes. Articles were systematically collected from the SCOPUS, PubMed, EconLit and Web of Science databases. Due to the heterogeneous nature of the evidence considered, the 16 included articles were subdivided into individual level data analyses, selected country analyses and international panel analyses. Articles were then quality assessed using a tool developed as part of the project. Nine of the studies were assessed to be high quality, six as medium quality, and one as low quality. The evidence from the quantitative literature suggests that overall, there appears to be a beneficial association between international trade and population health. There was also evidence of the importance of foreign direct investment, yet a lack of research considering the direction of causality. Taken together, quantitative research into the relationship between trade and non-nutritional health indicates trade to be beneficial, yet this body of research is still in its infancy. Future quantitative studies based on this foundation will provide a stronger basis on which to inform relevant national and international institutions about the health consequences of trade policies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Quantitative bone scintigraphy. A study in patients with prostatic carcinoma

International Nuclear Information System (INIS)

Sundkvist, G.

1991-01-01

Quantitative bone scintigraphy was performed in patients with prostatic carcinoma before orchiectomy as well as two weeks, two and six months after operation. The count rate was recorded as serial gamma camera images over the lower thoracic and all lumbar vertebrae from 1 to 240 min and at 24 h after injection of 99T c m -MDP. In almost all abnormal vertebrae an increased count rate was observed within one hour after injection. Most of the vertebrae which were considered normal at 4 h after injection, but had an increased 24h/4h ratio developed into abnormal vertebrae later in the study. The patients with normal bone scintigrams showed no change in 99 Tc m -MDP uptake during the study. The reproducibility of quantitative bone scintigraphy was found to be ± 7% (1 SD). In response to therapy, most of the patients with abnormal bone scintigrams showed an increase in count rate two weeks after operation followed by a decrease to the pre-operative level after two months and a further decrease after six months. This so called 'flare phenomenon' was found to indicate 99 Tc m -MDP in the vascular phase as well as an active bone uptake. In some of the patients the whole-body retention of 99 Tc m -MDP after 24 h and the bone mineral density in the vertebrae were determined and found to be valuable in the interpretation of skeletal metastases and the assessment of response to therapy. (71 refs.)

Increased expression of Golgi phosphoprotein-3 is associated with tumor aggressiveness and poor prognosis of prostate cancer

Directory of Open Access Journals (Sweden)

Hua Xing

2012-09-01

Full Text Available Abstract Background To investigate the expression of Golgi phosphoprotein-3 (GOLPH3 in prostate cancer and determine its prognostic value. Methods Immunohistochemical staining for GOLPH3 was performed on tissue microarrays of 342 prostate patients. The correlation between GOLPH3 expression with its clinicopathologic factors was also analyzed in order to determine its prognostic significance. Results GOLPH3 expression of normal prostate tissues, benign prostate hyperplasia, high-grade prostatic intraepithelial neoplasia, and hormone-dependent prostate cancer (HDPC did not show any statistically significant difference. In contrast, statistically significant difference was reported in moderate/intense GOLPH3 expression in cases diagnosed with HDPC and castration resistant prostate cancer (CRPC (P P = 0.012, higher Gleason score (P = 0.017, bone metastasis (P = 0.024, higher baseline prostate-specific antigen (PSA (P = 0.038, and higher PSA nadir (P = 0.032. A significantly negative correlation was found between moderate/intense GOLPH3 expression and disease-free survival (DFS (HR = 0.28, P = 0.012 and overall survival (OS (HR = 0.42, P = 0.027. Univariated analysis indicated that moderate/intense GOLPH3 expression created a significantly prognostic impact in patients with CRPC. On the other hand, multivariate analysis indicated that GOLPH3 was a significantly independent prognostic factor of DFS (P = 0.027 in all prostate cancer patients. Conclusions In this study, it was discovered that the overexpression of GOLPH3 is associated with the transition of prostate cancer from hormone sensitive phase to hormone refractory phase. GOLPH3 might be an important prognostic factor of DFS and OS in patients with prostate cancer. In totality, GOLPH3 could be used as a novel candidate in devising a more effective therapeutic strategy to tackle CRPC. Virtual slides The virtual slide(s for this article can be found here

Combining qualitative with quantitative approaches to study contraceptive pill use.

Science.gov (United States)

Oakley, D; Yu, M Y; Zhang, Y M; Zhu, X L; Chen, W H; Yao, L

1999-03-01

According to large-scale studies, oral contraceptive users become pregnant at rates that exceed ideal use failure rates. It is thought that a major cause is missed pills, but current research on consistent contraceptive pill taking is characterized by inadequate measures and a failure to investigate women's thinking about their own patterns of use. The purpose of this study was to gain some understanding about women's interpretations of consistency in their own pill taking through combining qualitative with quantitative data. The study was conducted in China, where contraception is free and widely available. Five urban and five rural oral contraceptive users were followed for up to three pill-taking cycles during 1996 for a total of 759 person-days. Consistency of pill taking was measured with electronic data obtained from a new blister package made by Anderson Clinical Technologies (Elmhurst, IL). Data from these devices were reviewed and interpreted by the study participants during in-depth private interviews. The users' reasons for missing pills included disruptions in their daily routines, their husband's absence, spotting, and trouble implementing the family planning program's instructions to take one pill per day for 22 days and start the next cycle on the fifth day of menses. One user gave these reasons for two cycles but denied missing numerous pills in her third cycle. Data from a series of four questionnaires showed that most demographic, psychosocial, and service system characteristics were not related to missed pills. However, results suggested that the daily routines of rural living may make consistent use more likely and that instructions for taking the pill may be associated with prolonged pill-free intervals and skipping pills during episodes of spotting. Three of the 10 women were at increased risk of pregnancy during the study period because of their pill-taking pattern. We concluded that the combination of qualitative with quantitative data

[Studies of biologic activation associated with molecular receptor increase and tumor response in ChL6/L6 protocol patients; Studies in phantoms; Quantitative SPECT; Preclinical studies; and Clinical studies]. DOE annual report, 1994-95

International Nuclear Information System (INIS)

DeNardo, S.J.

1995-01-01

The authors describe results which have not yet been published from their associated studies listed in the title. For the first, they discuss Lym-1 single chain genetically engineered molecules, analysis of molecular genetic coded messages to enhance tumor response, and human dosimetry and therapeutic human use radiopharmaceuticals. Studies in phantoms includes a discussion of planar image quantitation, counts coincidence correction, organ studies, tumor studies, and 90 Y quantitation with Bremsstrahlung imaging. The study on SPECT discusses attenuation correction and scatter correction. Preclinical studies investigated uptake of 90 Y-BrE-3 in mice using autoradiography. Clinical studies discuss image quantitation verses counts from biopsy samples, S factors for radiation dose calculation, 67 Cu imaging studies for lymphoma cancer, and 111 In MoAb imaging studies for breast cancer to predict 90 Y MoAb therapy

Being a quantitative interviewer: qualitatively exploring interviewers' experiences in a longitudinal cohort study

Directory of Open Access Journals (Sweden)

Derrett Sarah

2011-12-01

Full Text Available Abstract Background Many studies of health outcomes rely on data collected by interviewers administering highly-structured (quantitative questionnaires to participants. Little appears to be known about the experiences of such interviewers. This paper explores interviewer experiences of working on a longitudinal study in New Zealand (the Prospective Outcomes of injury Study - POIS. Interviewers administer highly-structured questionnaires to participants, usually by telephone, and enter data into a secure computer program. The research team had expectations of interviewers including: consistent questionnaire administration, timeliness, proportions of potential participants recruited and an empathetic communication style. This paper presents results of a focus group to qualitatively explore with the team of interviewers their experiences, problems encountered, strategies, support systems used and training. Methods A focus group with interviewers involved in the POIS interviews was held; it was audio-recorded and transcribed. The analytical method was thematic, with output intended to be descriptive and interpretive. Results Nine interviewers participated in the focus group (average time in interviewer role was 31 months. Key themes were: 1 the positive aspects of the quantitative interviewer role (i.e. relationships and resilience, insights gained, and participants' feedback, 2 difficulties interviewers encountered and solutions identified (i.e. stories lost or incomplete, forgotten appointments, telling the stories, acknowledging distress, stories reflected and debriefing and support, and 3 meeting POIS researcher expectations (i.e. performance standards, time-keeping, dealing exclusively with the participant and maintaining privacy. Conclusions Interviewers demonstrated great skill in the way they negotiated research team expectations whilst managing the relationships with participants. Interviewers found it helpful to have a research protocol in

Religion and body weight: a review of quantitative studies.

Science.gov (United States)

Yeary, Karen Hye-Cheon Kim; Sobal, Jeffery; Wethington, Elaine

2017-10-01

Increasing interest in relationships between religion and health has encouraged research about religion and body weight, which has produced mixed findings. We systematically searched 11 bibliographic databases for quantitative studies of religion and weight, locating and coding 85 studies. We conducted a systematic review, analysing descriptive characteristics of the studies as well as relevant religion-body weight associations related to study characteristics. We summarized findings for two categories of religion variables: religious affiliation and religiosity. For religious affiliation, we found evidence for significant associations with body weight in both cross-sectional and longitudinal studies. In particular, Seventh-Day Adventists had lower body weight than other denominations in cross-sectional analyses. For religiosity, significant associations occurred between greater religiosity and higher body weight in both cross-sectional and longitudinal studies. In particular, greater religiosity was significantly associated with higher body weight in bivariate analyses but less so in multivariate analyses. A greater proportion of studies that used a representative sample, longitudinal analyses, and samples with only men reported significant associations between religiosity and weight. Evidence in seven studies suggested that health behaviours and psychosocial factors mediate religion-weight relationships. More longitudinal studies and analyses of mediators are needed to provide stronger evidence and further elucidate religion-weight relationships. © 2017 World Obesity Federation.

Prediction of quantitative phenotypes based on genetic networks: a case study in yeast sporulation

Directory of Open Access Journals (Sweden)

Shen Li

2010-09-01

Full Text Available Abstract Background An exciting application of genetic network is to predict phenotypic consequences for environmental cues or genetic perturbations. However, de novo prediction for quantitative phenotypes based on network topology is always a challenging task. Results Using yeast sporulation as a model system, we have assembled a genetic network from literature and exploited Boolean network to predict sporulation efficiency change upon deleting individual genes. We observe that predictions based on the curated network correlate well with the experimentally measured values. In addition, computational analysis reveals the robustness and hysteresis of the yeast sporulation network and uncovers several patterns of sporulation efficiency change caused by double gene deletion. These discoveries may guide future investigation of underlying mechanisms. We have also shown that a hybridized genetic network reconstructed from both temporal microarray data and literature is able to achieve a satisfactory prediction accuracy of the same quantitative phenotypes. Conclusions This case study illustrates the value of predicting quantitative phenotypes based on genetic network and provides a generic approach.

Quantitative FDG in depression

Energy Technology Data Exchange (ETDEWEB)

Chua, P.; O`Keefe, G.J.; Egan, G.F.; Berlangieri, S.U.; Tochon-Danguy, H.J.; Mckay, W.J.; Morris, P.L.P.; Burrows, G.D. [Austin Hospital, Melbourne, VIC (Australia). Dept of Psychiatry and Centre for PET

1998-03-01

Full text: Studies of regional cerebral glucose metabolism (rCMRGlu) using positron emission tomography (PET) in patients with affective disorders have consistently demonstrated reduced metabolism in the frontal regions. Different quantitative and semi-quantitative rCMRGlu regions of interest (ROI) comparisons, e.g. absolute metabolic rates, ratios of dorsolateral prefrontal cortex (DLPFC) to ipsilateral hemisphere cortex, have been reported. These studies suffered from the use of a standard brain atlas to define ROls, whereas in this case study, the individual``s magnetic resonance imaging (MRI) scan was registered with the PET scan to enable accurate neuroanatomical ROI definition for the subject. The patient is a 36-year-old female with a six-week history of major depression (HAM-D = 34, MMSE = 28). A quantitative FDG PET study and an MRI scan were performed. Six MRI-guided ROls (DLPFC, PFC, whole hemisphere) were defined. The average rCMRGlu in the DLPFC (left = 28.8 + 5.8 mol/100g/min; right = 25.6 7.0 mol/100g/min) were slightly reduced compared to the ipsilateral hemispherical rate (left = 30.4 6.8 mol/100g/min; right = 29.5 7.2 mol/100g/min). The ratios of DLPFC to ipsilateral hemispheric rate were close to unity (left = 0.95 0.29; right 0.87 0.32). The right to left DLPFC ratio did not show any significant asymmetry (0.91 0.30). These results do not correlate with earlier published results reporting decreased left DLPFC rates compared to right DLPFC, although our results will need to be replicated with a group of depressed patients. Registration of PET and MRI studies is necessary in ROI-based quantitative FDG PET studies to allow for the normal anatomical variation among individuals, and thus is essential for accurate comparison of rCMRGlu between individuals.

Quantitative FDG in depression

International Nuclear Information System (INIS)

Chua, P.; O'Keefe, G.J.; Egan, G.F.; Berlangieri, S.U.; Tochon-Danguy, H.J.; Mckay, W.J.; Morris, P.L.P.; Burrows, G.D.

1998-01-01

Full text: Studies of regional cerebral glucose metabolism (rCMRGlu) using positron emission tomography (PET) in patients with affective disorders have consistently demonstrated reduced metabolism in the frontal regions. Different quantitative and semi-quantitative rCMRGlu regions of interest (ROI) comparisons, e.g. absolute metabolic rates, ratios of dorsolateral prefrontal cortex (DLPFC) to ipsilateral hemisphere cortex, have been reported. These studies suffered from the use of a standard brain atlas to define ROls, whereas in this case study, the individual''s magnetic resonance imaging (MRI) scan was registered with the PET scan to enable accurate neuroanatomical ROI definition for the subject. The patient is a 36-year-old female with a six-week history of major depression (HAM-D = 34, MMSE = 28). A quantitative FDG PET study and an MRI scan were performed. Six MRI-guided ROls (DLPFC, PFC, whole hemisphere) were defined. The average rCMRGlu in the DLPFC (left = 28.8 + 5.8 mol/100g/min; right = 25.6 7.0 mol/100g/min) were slightly reduced compared to the ipsilateral hemispherical rate (left = 30.4 6.8 mol/100g/min; right = 29.5 7.2 mol/100g/min). The ratios of DLPFC to ipsilateral hemispheric rate were close to unity (left = 0.95 0.29; right 0.87 0.32). The right to left DLPFC ratio did not show any significant asymmetry (0.91 0.30). These results do not correlate with earlier published results reporting decreased left DLPFC rates compared to right DLPFC, although our results will need to be replicated with a group of depressed patients. Registration of PET and MRI studies is necessary in ROI-based quantitative FDG PET studies to allow for the normal anatomical variation among individuals, and thus is essential for accurate comparison of rCMRGlu between individuals

The nuclear retention signal of HPV16 L2 protein is essential for incoming viral genome to transverse the trans-Golgi network

International Nuclear Information System (INIS)

DiGiuseppe, Stephen; Bienkowska-Haba, Malgorzata; Hilbig, Lydia; Sapp, Martin

2014-01-01

The Human papillomavirus (HPV) capsid is composed of the major and minor capsid proteins, L1 and L2, respectively. Infectious entry requires a complex series of conformational changes in both proteins that lead to uptake and allow uncoating to occur. During entry, the capsid is disassembled and host cyclophilins dissociate L1 protein from the L2/DNA complex. Herein, we describe a mutant HPV16 L2 protein (HPV16 L2-R302/5A) that traffics pseudogenome to the trans-Golgi network (TGN) but fails to egress. Our data provide further evidence that HPV16 traffics through the TGN and demonstrates that L2 is essential for TGN egress. Furthermore, we show that cyclophilin activity is required for the L2/DNA complex to be transported to the TGN which is accompanied by a reduced L1 protein levels. - Highlights: • mNLS mutant HPV16 L2 protein traffics pseudogenome to the TGN but fails to egress. • Cyclophilin activity is required for trafficking of the L2/DNA complex to the TGN. • Majority of L1 protein is shed from the L2/DNA complex prior to reaching the TGN

The nuclear retention signal of HPV16 L2 protein is essential for incoming viral genome to transverse the trans-Golgi network

Energy Technology Data Exchange (ETDEWEB)

DiGiuseppe, Stephen; Bienkowska-Haba, Malgorzata; Hilbig, Lydia; Sapp, Martin, E-mail: msapp1@lsuhsc.edu

2014-06-15

The Human papillomavirus (HPV) capsid is composed of the major and minor capsid proteins, L1 and L2, respectively. Infectious entry requires a complex series of conformational changes in both proteins that lead to uptake and allow uncoating to occur. During entry, the capsid is disassembled and host cyclophilins dissociate L1 protein from the L2/DNA complex. Herein, we describe a mutant HPV16 L2 protein (HPV16 L2-R302/5A) that traffics pseudogenome to the trans-Golgi network (TGN) but fails to egress. Our data provide further evidence that HPV16 traffics through the TGN and demonstrates that L2 is essential for TGN egress. Furthermore, we show that cyclophilin activity is required for the L2/DNA complex to be transported to the TGN which is accompanied by a reduced L1 protein levels. - Highlights: • mNLS mutant HPV16 L2 protein traffics pseudogenome to the TGN but fails to egress. • Cyclophilin activity is required for trafficking of the L2/DNA complex to the TGN. • Majority of L1 protein is shed from the L2/DNA complex prior to reaching the TGN.

Cytochemical and x-ray microanalysis studies of intracellular calcium pools in scale-bearing cells of the coccolithophorid emiliana huxleyi

International Nuclear Information System (INIS)

Wal, P. van der; Bruijn, W.C. de; Westbroek, P.

1985-01-01

Emiliania huxleyi is a coccolithophorid with a life cycle including a stage characterized by the occurrence of a scale-bearing cell type. The scales are composed of organic material and are produced in the cisternae of the Golgi apparatus. The present report deals with the ultrastructural calcium localization in scale-bearing cells using cation-precipitating agents. Cations were precipitated either with potassium carbonate, or potassium phosphate, and then with potassium pyroantimonate. The distribution of electron-opaque deposits was the same when visualized by all four techniques. The most extensive deposits occurred in the Golgi apparatus, the 'peripheral space' (a cellular compartment totally encompassing the protoplast), the multivesicular bodies, and the cell vacuole. X-ray microanalysis revealed that calcium was a constituent of the electron-opaque deposits. The uptake and transport of calcium, as universal functions of the Golgi apparatus, are discussed. (Author)

Effects of adult dysthyroidism on the morphology of hippocampal granular cells in rats.

Science.gov (United States)

Martí-Carbonell, Maria Assumpció; Garau, Adriana; Sala-Roca, Josefina; Balada, Ferran

2012-01-01

Thyroid hormones are essential for normal brain development and very important in the normal functioning of the brain. Thyroid hormones action in the adult brain has not been widely studied. The effects of adult hyperthyroidism are not as well understood as adult hypothyroidism, mainly in hippocampal granular cells. The purpose of the present study is to assess the consequences of adult hormone dysthyroidism (excess/deficiency of TH) on the morphology of dentate granule cells in the hippocampus by performing a quantitative study of dendritic arborizations and dendritic spines using Golgi impregnated material. Hypo-and hyperthyroidism were induced in rats by adding 0.02 percent methimazole and 1 percent L-thyroxine, respectively, to drinking water from 40 days of age. At 89 days, the animals' brains were removed and stained by a modified Golgi method and blood samples were collected in order to measure T4 serum levels. Neurons were selected and drawn using a camera lucida. Our results show that both methimazole and thyroxine treatment affect granule cell morphology. Treatments provoke alterations in the same direction, namely, reduction of certain dendritic-branching parameters that are more evident in the methimazole than in the thyroxine group. We also observe a decrease in spine density in both the methimazole and thyroxine groups.

What Really Happens in Quantitative Group Research? Results of a Content Analysis of Recent Quantitative Research in "JSGW"

Science.gov (United States)

Boyle, Lauren H.; Whittaker, Tiffany A.; Eyal, Maytal; McCarthy, Christopher J.

2017-01-01

The authors conducted a content analysis on quantitative studies published in "The Journal for Specialists in Group Work" ("JSGW") between 2012 and 2015. This brief report provides a general overview of the current practices of quantitative group research in counseling. The following study characteristics are reported and…

Leaving Quietly? A Quantitative Study of Retirement Rituals and How They Affect Life Satisfaction

NARCIS (Netherlands)

van den Bogaard, L.

2017-01-01

This study quantitatively explores the understudied topic of retirement rituals, what factors influence them, and how the experience of such rites of passage may affect postretirement satisfaction with life (SWL). Various regression techniques are applied to 2 waves of Dutch panel data gathered

Quantitative proteomic study of Aspergillus Fumigatus secretome revealed deamidation of secretory enzymes.

Science.gov (United States)

Adav, Sunil S; Ravindran, Anita; Sze, Siu Kwan

2015-04-24

Aspergillus sp. plays an essential role in lignocellulosic biomass recycling and is also exploited as cell factories for the production of industrial enzymes. This study profiled the secretome of Aspergillus fumigatus when grown with cellulose, xylan and starch by high throughput quantitative proteomics using isobaric tags for relative and absolute quantification (iTRAQ). Post translational modifications (PTMs) of proteins play a critical role in protein functions. However, our understanding of the PTMs in secretory proteins is limited. Here, we present the identification of PTMs such as deamidation of secreted proteins of A. fumigatus. This study quantified diverse groups of extracellular secreted enzymes and their functional classification revealed cellulases and glycoside hydrolases (32.9%), amylases (0.9%), hemicellulases (16.2%), lignin degrading enzymes (8.1%), peptidases and proteases (11.7%), chitinases, lipases and phosphatases (7.6%), and proteins with unknown function (22.5%). The comparison of quantitative iTRAQ results revealed that cellulose and xylan stimulates expression of specific cellulases and hemicellulases, and their abundance level as a function of substrate. In-depth data analysis revealed deamidation as a major PTM of key cellulose hydrolyzing enzymes like endoglucanases, cellobiohydrolases and glucosidases. Hemicellulose degrading endo-1,4-beta-xylanase, monosidases, xylosidases, lignin degrading laccase, isoamyl alcohol oxidase and oxidoreductases were also found to be deamidated. The filamentous fungi play an essential role in lignocellulosic biomass recycling and fungal strains belonging to Aspergillus were also exploited as cell factories for the production of organic acids, pharmaceuticals, and industrially important enzymes. In this study, extracellular proteins secreted by thermophilic A. fumigatus when grown with cellulose, xylan and starch were profiled using isobaric tags for relative and absolute quantification (iTRAQ) by

Comparative quantitative studies on the radiosensitivity of the oral cavity epithelium

International Nuclear Information System (INIS)

Lyubenov, T.

1986-01-01

A series of 146 patients with miscellaneous localizations of malignant tumors in the head and neck area, in whom different portions of the oral cavity epithelium came within the field subject to irradiation were included in the study. Using the Kirk's formula for cumulative radiation effect, quantitative relationships in the manifestation of radioepithelitis were searched for. With increasing the intervals of the cumulative radiation effect, the number of patients and the number of interruptions in treatment with different localizations of the tumor depended on epithelium radiosensitivity

A study on a quantitative V and V for safety-critical software

International Nuclear Information System (INIS)

Eom, Heung Seop; Son, Han Seong; Kang, Hyun Gook; Chang, Seung Cheol

2004-01-01

Verification and Validation (V and V) plays important role in assessing the safety-critical software embedded in the digital systems for a Nuclear Power Plant. A conventional V and V usually adopts a checklist method and its answers are mostly qualitative. There are some limitations to this conventional V and V method. First, the difficulties in using the checklist method are: Even for an acceptable software, some checklist questions will have negative answers. The checklist itself does not help to explain the reasons for drawing an overall positive conclusion in the presence of a few negative answers. The checklist does not help decide when enough issues have been examined to achieve a reasonable confidence in the software. The checklist method does not support a consideration of different kinds of information, such as software engineering measures. Second, a difficulty comes from the qualitative form of the answers in the checklist method, which is: It is usually hard to know when sufficient evidence has been collected. Finally a difficulty comes from a human expert's way of combining a great number of diverse evidence and inferring the conclusion, which is: Some of this evidence is qualitative and others are quantitative. Both are necessary to evaluate the quality of the software correctly. But, in general, the experts' way of combining the diverse evidence and performing an inference is usually informal and qualitative, which is hard to discuss and will eventually lead to a debate about the conclusion. Our overall goal is to develop a systematic method that can obtain quantitative information of the software quality from the works of V and V. To achieve this goal and to solve the above-mentioned problems in the current V and V method, we studied a method that can combine qualitative and quantitative evidence, and can infer a conclusion in a formal and a quantitative way by using the benefits of BBN

GOLGA2 loss causes fibrosis with autophagy in the mouse lung and liver.

Science.gov (United States)

Park, Sungjin; Kim, Sanghwa; Kim, Min Jung; Hong, Youngeun; Lee, Ah Young; Lee, Hyunji; Tran, Quangdon; Kim, Minhee; Cho, Hyeonjeong; Park, Jisoo; Kim, Kwang Pyo; Park, Jongsun; Cho, Myung-Haing

2018-01-01

Autophagy is a biological recycling process via the self-digestion of organelles, proteins, and lipids for energy-consuming differentiation and homeostasis. The Golgi serves as a donor of the double-membraned phagophore for autophagosome assembly. In addition, recent studies have demonstrated that pulmonary and hepatic fibrosis is accompanied by autophagy. However, the relationships among Golgi function, autophagy, and fibrosis are unclear. Here, we show that the deletion of GOLGA2, encoding a cis-Golgi protein, induces autophagy with Golgi disruption. The induction of autophagy leads to fibrosis along with the reduction of subcellular lipid storage (lipid droplets and lamellar bodies) by autophagy in the lung and liver. GOLGA2 knockout mice clearly demonstrated fibrosis features such as autophagy-activated cells, densely packed hepatocytes, increase of alveolar macrophages, and decrease of alveolar surfactant lipids (dipalmitoylphosphatidylcholine). Therefore, we confirmed the associations among Golgi function, fibrosis, and autophagy. Moreover, GOLGA2 knockout mice may be a potentially valuable animal model for studying autophagy-induced fibrosis. Copyright © 2017 Elsevier Inc. All rights reserved.

Italian version of Dyspnoea-12: cultural-linguistic validation, quantitative and qualitative content validity study.

Science.gov (United States)

Caruso, Rosario; Arrigoni, Cristina; Groppelli, Katia; Magon, Arianna; Dellafiore, Federica; Pittella, Francesco; Grugnetti, Anna Maria; Chessa, Massimo; Yorke, Janelle

2018-01-16

Dyspnoea-12 is a valid and reliable scale to assess dyspneic symptom, considering its severity, physical and emotional components. However, it is not available in Italian version due to it was not yet translated and validated. For this reason, the aim of this study was to develop an Italian version Dyspnoea-12, providing a cultural and linguistic validation, supported by the quantitative and qualitative content validity. This was a methodological study, divided into two phases: phase one is related to the cultural and linguistic validation, phase two is related to test the quantitative and qualitative content validity. Linguistic validation followed a standardized translation process. Quantitative content validity was assessed computing content validity ratio (CVR) and index (I-CVIs and S-CVI) from expert panellists response. Qualitative content validity was assessed by the narrative analysis on the answers of three open-ended questions to the expert panellists, aimed to investigate the clarity and the pertinence of the Italian items. The translation process found a good agreement in considering clear the items in both the six involved bilingual expert translators and among the ten voluntary involved patients. CVR, I-CVIs and S-CVI were satisfactory for all the translated items. This study has represented a pivotal step to use Dyspnoea-12 amongst Italian patients. Future researches are needed to deeply investigate the Italian version of  Dyspnoea-12 construct validity and its reliability, and to describe how dyspnoea components (i.e. physical and emotional) impact the life of patients with cardiorespiratory diseases.

Quantitative application study on the control system of contract progress

International Nuclear Information System (INIS)

Hu Xiaocong; Kang Rujie; Zhan Li

2012-01-01

Quantitative application study on the control system of contract progress, which is based on project management theory and PDCA cycle methods, provides a new way for the contract business management of enterprise, in line with the current situation and the nuclear power enterprise performance management needs. The concept of the system, system development, program design and development of ERP (VBA design) which come from the work experience summary of business managers are convenient and feasible in practical applications. By way of the applications in 2009, 2010, 2011 three-year overhaul contract management and continuous adjustment it has become an important business management tool, which not only effectively guaranteed the contract time and efficiency, but also combines the performance management and contract progress management. This study has provided useful reference for the enterprise management. (authors)

Quantitative analysis of stress thallium-201 studies: comparison of SPET and planar imaging in the detection of CAD

International Nuclear Information System (INIS)

Ziada, G.; Hayat, N.; Abdel-Dayem, H.M.; Hassan, I.

1986-01-01

The value of thallium-201 tomographic sections in the detection of coronary artery disease is illustrated by comparing visual interpretation (VTS) and quantitative analysis (QTS) with visual planar study (VPS) and quantitative analysis of planar study (QPS), referring to coronary angiography (CA) as the standard technique. It is concluded that visual assessment of single photon emission tomography (VTS) is more valuable than all other techniques (VPS, QPS and QTS) for detecting and localizing coronary artery disease. (UK)

Consequences of dispersal for the quantitative study of adaptation in small-scale plots: a case study of an avian island population

NARCIS (Netherlands)

Lambrechts, M.M.; Visser, M.E.; Verboven, N.

2000-01-01

Lifetime recruitment of breeding offspring estimated in small- scale study plots (i.e local recruitment) is considered to be the best available ecological measure of contributions to following generations, and sufficient for the quantitative study of adaptation in natural populations. Recent

QUANTITATIVE STUDY OF THE WORLD MARKET OF MEAT

Directory of Open Access Journals (Sweden)

Elena COFAS

2013-01-01

Full Text Available This study presents the evolution of global market of meat in 2007-2011 and has been possible because the authors used an important set of indicators, namely: livestock, achieved production, imports, exports, trade balance, price etc. The data used in this work was provided by the following institutions accredited for collecting and processing statistical data: National Institute of Statistics, EUROSTAT, FAOSTAT, FAPRI and USDA. The analysis global market of meat is primarily a quantitative analysis. In the period which is analysed, the demand, the production, the imports, the exports and the prices have evolved differently, especially meat categories, so all these indicators have influenced global market of meat. In mainly, the meat consumption is influenced by the pattern of food consumption and price level. In the future, expect a increase prices, which is based on increasing production costs. Therefore, first it is necessary to adopt measures to support the farmers.

A study of quantitative scale display of the organ uptake with gamma-camera

Energy Technology Data Exchange (ETDEWEB)

Ishigami, K; Matsumoto, M [Kumamoto Univ. (Japan) School of Medicine

1975-05-01

The fundamental study of quantitative scale display of the organ uptake with ..gamma..-camera was performed in special respect of the thyroid gland and the pancreas. As one of the measurements on certain dimension of the organ, an optical progression outside the digital image was expressed, and was subjected to the quantitative scale with the use of the threshold level. And a rather satisfactory correlation was clinically obtained between the scale display and the thyroidal /sup 131/I uptake. For the purpose of revising the above scale display, the organ depth was measured with RI by the aid of the phantom. Then the pancreas depth determined by the count rate ratio curve of 140 and 270 keV peak of /sup 75/Se energies. However, the body background and the radioactive rays from the neighboring organs interfered with this curve.

Quantitative fetal fibronectin and cervical length in symptomatic women: results from a prospective blinded cohort study.

Science.gov (United States)

Levine, Lisa D; Downes, Katheryne L; Romero, Julie A; Pappas, Hope; Elovitz, Michal A

2018-05-15

Our objectives were to determine whether quantitative fetal fibronectin (fFN) and cervical length (CL) screening can be used alone or in combination as prognostic tests to identify symptomatic women at the highest or lowest risk for spontaneous preterm birth (sPTB). A prospective, blinded cohort study of women presenting with a singleton gestation to our triage unit between 22-33w6d with preterm labor symptoms was performed. Women with ruptured membranes, moderate/severe bleeding, and dilation >2 cm were excluded. The primary outcome was sPTB quantitative fFN and CL assessment, both separately and in combination, considering traditionally reported cut-points (fFN ≥50 and CL 50 and CL quantitative level chosen. For all women, a shorter CL was associated with an increased sPTB risk. Among nulliparas and multiparas without a prior sPTB, a CL quantitative fFN or cervical length assessment can be utilized, depending on resources available, but a lower cut-point of 20 ng/mL should be used for quantitative fFN. For multiparous women, fFN is not useful and cervical length assessment should be the main screening tool utilized when there is clinical uncertainty. Regardless of parity, the PPV of fFN and CL is low and therefore the greatest clinical utility remains in its NPV.

Annotation of loci from genome-wide association studies using tissue-specific quantitative interaction proteomics

NARCIS (Netherlands)

Lundby, Alicia; Rossin, Elizabeth J.; Steffensen, Annette B.; Acha, Moshe Ray; Newton-Cheh, Christopher; Pfeufer, Arne; Lyneh, Stacey N.; Olesen, Soren-Peter; Brunak, Soren; Ellinor, Patrick T.; Jukema, J. Wouter; Trompet, Stella; Ford, Ian; Macfarlane, Peter W.; Krijthe, Bouwe P.; Hofman, Albert; Uitterlinden, Andre G.; Stricker, Bruno H.; Nathoe, Hendrik M.; Spiering, Wilko; Daly, Mark J.; Asselbergs, Ikea W.; van der Harst, Pim; Milan, David J.; de Bakker, Paul I. W.; Lage, Kasper; Olsen, Jesper V.

Genome-wide association studies (GWAS) have identified thousands of loci associated with complex traits, but it is challenging to pinpoint causal genes in these loci and to exploit subtle association signals. We used tissue-specific quantitative interaction proteomics to map a network of five genes

Quantitative methods in psychology: inevitable and useless

Directory of Open Access Journals (Sweden)

Aaro Toomela

2010-07-01

Full Text Available Science begins with the question, what do I want to know? Science becomes science, however, only when this question is justified and the appropriate methodology is chosen for answering the research question. Research question should precede the other questions; methods should be chosen according to the research question and not vice versa. Modern quantitative psychology has accepted method as primary; research questions are adjusted to the methods. For understanding thinking in modern quantitative psychology, two epistemologies should be distinguished: structural-systemic that is based on Aristotelian thinking, and associative-quantitative that is based on Cartesian-Humean thinking. The first aims at understanding the structure that underlies the studied processes; the second looks for identification of cause-effect relationships between the events with no possible access to the understanding of the structures that underlie the processes. Quantitative methodology in particular as well as mathematical psychology in general, is useless for answering questions about structures and processes that underlie observed behaviors. Nevertheless, quantitative science is almost inevitable in a situation where the systemic-structural basis of behavior is not well understood; all sorts of applied decisions can be made on the basis of quantitative studies. In order to proceed, psychology should study structures; methodologically, constructive experiments should be added to observations and analytic experiments.

Quantitative study of Xanthosoma violaceum leaf surfaces using RIMAPS and variogram techniques.

Science.gov (United States)

Favret, Eduardo A; Fuentes, Néstor O; Molina, Ana M

2006-08-01

Two new imaging techniques (rotated image with maximum averaged power spectrum (RIMAPS) and variogram) are presented for the study and description of leaf surfaces. Xanthosoma violaceum was analyzed to illustrate the characteristics of both techniques. Both techniques produce a quantitative description of leaf surface topography. RIMAPS combines digitized images rotation with Fourier transform, and it is used to detect patterns orientation and characteristics of surface topography. Variogram relates the mathematical variance of a surface with the area of the sample window observed. It gives the typical scale lengths of the surface patterns. RIMAPS detects the morphological variations of the surface topography pattern between fresh and dried (herbarium) samples of the leaf. The variogram method finds the characteristic dimensions of the leaf microstructure, i.e., cell length, papillae diameter, etc., showing that there are not significant differences between dry and fresh samples. The results obtained show the robustness of RIMAPS and variogram analyses to detect, distinguish, and characterize leaf surfaces, as well as give scale lengths. Both techniques are tools for the biologist to study variations of the leaf surface when different patterns are present. The use of RIMAPS and variogram opens a wide spectrum of possibilities by providing a systematic, quantitative description of the leaf surface topography.

Acute ethanol exposure inhibits silencing of cerebellar Golgi cell firing induced by granule cell axon input

Directory of Open Access Journals (Sweden)

Paolo eBotta

2014-02-01

Full Text Available Golgi cells (GoCs are specialized interneurons that provide inhibitory input to granule cells in the cerebellar cortex. GoCs are pacemaker neurons that spontaneously fire action potentials, triggering spontaneous inhibitory postsynaptic currents in granule cells and also contributing to the generation tonic GABAA receptor-mediated currents in granule cells. In turn, granule cell axons provide feedback glutamatergic input to GoCs. It has been shown that high frequency stimulation of granule cell axons induces a transient pause in GoC firing in a type 2-metabotropic glutamate receptor (mGluR2-dependent manner. Here, we investigated the effect ethanol on the pause of GoC firing induced by high frequency stimulation of granule cell axons. GoC electrophysiological recordings were performed in parasagittal cerebellar vermis slices from postnatal day 23 to 26 rats. Loose-patch cell-attached recordings revealed that ethanol (40 mM reversibly decreases the pause duration. An antagonist of mGluR2 reduced the pause duration but did not affect the effect of ethanol. Whole-cell voltage-clamp recordings showed that currents evoked by an mGluR2 agonist were not significantly affected by ethanol. Perforated-patch experiments in which hyperpolarizing and depolarizing currents were injected into GoCs demonstrated that there is an inverse relationship between spontaneous firing and pause duration. Slight inhibition of the Na+/K+ pump mimicked the effect of ethanol on pause duration. In conclusion, ethanol reduces the granule cell axon-mediated feedback mechanism by reducing the input responsiveness of GoCs. This would result in a transient increase of GABAA receptor-mediated inhibition of granule cells, limiting information flow at the input stage of the cerebellar cortex.

Comparison of two methods of quantitation in human studies of biodistribution and radiation dosimetry

International Nuclear Information System (INIS)

Smith, T.

1992-01-01

A simple method of quantitating organ radioactivity content for dosimetry purposes based on relationships between organ count rate and the initial whole body count rate, has been compared with a more rigorous method of absolute quantitation using a transmission scanning technique. Comparisons were on the basis of organ uptake (% administered activity) and resultant organ radiation doses (mGy MBq -1 ) in 6 normal male volunteers given a 99 Tc m -labelled myocardial perfusion imaging agent intravenously at rest and following exercise. In these studies, estimates of individual organ uptakes by the simple method were in error by between +24 and -16% compared with the more accurate method. However, errors on organ dose values were somewhat less and the effective dose was correct to within 3%. (Author)

Quantitative cervical vertebral maturation assessment in adolescents with normal occlusion: a mixed longitudinal study.

Science.gov (United States)

Chen, Li-Li; Xu, Tian-Min; Jiang, Jiu-Hui; Zhang, Xing-Zhong; Lin, Jiu-Xiang

2008-12-01

The purpose of this study was to establish a quantitative cervical vertebral maturation (CVM) system for adolescents with normal occlusion. Mixed longitudinal data were used. The subjects included 87 children and adolescents from 8 to 18 years old with normal occlusion (32 boys, 55 girls) selected from 901 candidates. Sequential lateral cephalograms and hand-wrist films were taken once a year for 6 years. The lateral cephalograms of all subjects were divided into 11 maturation groups according to the Fishman skeletal maturity indicators. The morphologic characteristics of the second, third, and fourth cervical vertebrae at 11 developmental stages were measured and analyzed. Three characteristic parameters (H4/W4, AH3/PH3, @2) were selected to determine the classification of CVM. With 3 morphologic variables, the quantitative CVM system including 4 maturational stages was established. An equation that can accurately estimate the maturation of the cervical vertebrae was established: CVM stage=-4.13+3.57xH4/W4+4.07xAH3/PH3+0.03x@2. The quantitative CVM method is an efficient, objective, and relatively simple approach to assess the level of skeletal maturation during adolescence.

Quantitative analysis of normal thallium-201 tomographic studies

International Nuclear Information System (INIS)

Eisner, R.L.; Gober, A.; Cerqueira, M.

1985-01-01

To determine the normal (nl) distribution of Tl-201 uptake post exercise (EX) and at redistribution (RD) and nl washout, Tl-201 rotational tomographic (tomo) studies were performed in 40 subjects: 16 angiographic (angio) nls and 24 nl volunteers (12 from Emory and 12 from Yale). Oblique angle short axis slices were subjected to maximal count circumferential profile analysis. Data were displayed as a ''bullseye'' functional map with the apex at the center and base at the periphery. The bullseye was not uniform in all regions because of the variable effects of attenuation and resolution at different view angles. In all studies, the septum: lateral wall ratio was 1.0 in males and approximately equal to 1.0 in females. This occurred predominantly because of anterior defects due to breast soft tissue attenuation. EX and RD bullseyes were similar. Using a bi-exponential model for Tl kinetics, 4 hour normalized washout ranged 49-54% in each group and showed minimal variation between walls throughout the bullseye. Thus, there are well defined variations in Tl-201 uptake in the nl myocardium which must be taken into consideration when analyzing pt data. Because of these defects and the lack of adequate methods for attenuation correction, quantitative analysis of Tl-201 studies must include direct comparison with gender-matched nl data sets

A quantitative study of bone repair after endodontic therapy on digital subtraction radiography

International Nuclear Information System (INIS)

Kim, Jae Duk

1997-01-01

This study was performed to prepare the quantitative method of judging the sensitive prognosis of chronic apical periodontitis as early as possible. The subjects were 25 cases with periapical radiolucencies of which were treated with endodontic treatment. Serial radiographs were taken by standardized method longitudinally. The density slice function of digital radiographic system were employed for quantitative and longitudinal assessment of the radiolucent area and the condensing osteitis simultaneously. Obtained results were as follows: 1. The amount of bone repair after endodontic treatment could be detected quantitatively by the density slice function of digital radiographic system. 2. Within the 6-week period after root canal filling, the prognosis could be evaluated by assessment both radiolucent area and condensing osteitis on digital radiographic system. 3. The pattern of bone repair showed peripheral type in most cases from the 6th week after root canal filling. 4. In longitudinal change, bone repair showed two patterns; the succeeding reduction of radiolucent area showing the increase of condensing osteitis in size till 6th week and following by static state or reduction tendency and the reduction following the initial increase of both areas. 5. Cases with pulpitis by trauma showed initial increase of condensing osteitis at 2nd week, marked reduction of radiolucent area and condensing osteitis at 6th week, and approximately normal bone state at 8th week after root canal filling.

A quantitative study of bone repair after endodontic therapy on digital subtraction radiography

Energy Technology Data Exchange (ETDEWEB)

Kim, Jae Duk [Dept. of Oral and Maxillofacial Radiology, College of Dentistry, Chosun University, Kwangju (Korea, Republic of)

1997-08-15

This study was performed to prepare the quantitative method of judging the sensitive prognosis of chronic apical periodontitis as early as possible. The subjects were 25 cases with periapical radiolucencies of which were treated with endodontic treatment. Serial radiographs were taken by standardized method longitudinally. The density slice function of digital radiographic system were employed for quantitative and longitudinal assessment of the radiolucent area and the condensing osteitis simultaneously. Obtained results were as follows: 1. The amount of bone repair after endodontic treatment could be detected quantitatively by the density slice function of digital radiographic system. 2. Within the 6-week period after root canal filling, the prognosis could be evaluated by assessment both radiolucent area and condensing osteitis on digital radiographic system. 3. The pattern of bone repair showed peripheral type in most cases from the 6th week after root canal filling. 4. In longitudinal change, bone repair showed two patterns; the succeeding reduction of radiolucent area showing the increase of condensing osteitis in size till 6th week and following by static state or reduction tendency and the reduction following the initial increase of both areas. 5. Cases with pulpitis by trauma showed initial increase of condensing osteitis at 2nd week, marked reduction of radiolucent area and condensing osteitis at 6th week, and approximately normal bone state at 8th week after root canal filling.

The Study on the Quantitative Analysis in LPG Tank's Fire and Explosion

Energy Technology Data Exchange (ETDEWEB)

Bae, S.J.; Kim, B.J. [Department of chemical Engineering, Soongsil University, Seoul (Korea)

1999-04-01

Chemical plant's fire and explosion does not only damage to the chemical plants themselves but also damage to people in or near of the accident spot and the neighborhood of chemical plant. For that reason, Chemical process safety management has become important. One of safety management methods is called 'the quantitative analysis', which is used to reduce and prevent the accident. The results of the quantitative analysis could be used to arrange the equipments, evaluate the minimum safety distance, prepare the safety equipments. In this study we make the computer program to make easy to do quantitative analysis of the accident. The output of the computer program is the magnitude of fire(pool fire and fireball) and explosion (UVCE and BLEVE) effects. We used the thermal radiation as a measure of fire magnitude and used the overpressure as a measure of explosion magnitude. In case of BLEVE, the fly distance of fragment can be evaluated. Also probit analysis was done in every case. As the case study, Buchun LPG explosion accident in Korea was analysed by the program developed. The simulation results showed that the permissible distance was 800m and probit analysis showed that 1st degree burn, 2nd degree burn, and death distances are 450, 280, 260m, respectively. the simulation results showed the good agreement with the result from SAFER PROGRAM made by DuPont. 13 refs., 4 figs., 2 tabs.

Quantitative morphological analysis of proliferating and nonproliferating subpopulations of IMR-90 fibroblasts during aging in vitro

International Nuclear Information System (INIS)

Pool, T.B.; Heitman, T.O.; Buck, M.A.

1982-01-01

Early-, mid- and late-passage cultures (population doubling levels 12, 35, and 51, respectively) of IMR-90 fibroblasts were exposed to 3 H-thymidine for 48 h prior to fixation in situ for morphometric analysis in order to determine quantitatively what ultrastructural changes accompany the loss of proliferative capacity during aging in vitro. Analysis of autoradiographs, both at the light and electron microscopic levels, with an image analyzer followed by ANOVA statistical scrutiny demonstrated that a significant increase in relative cell area, an indicator of cell size, was characteristic of cells unable to incorporate 3 H-TdR at both mid- and late-passage, but not at early-passage levels. Nuclear size also increased significantly with progressive passage level but was not related to proliferative capacity. No significant difference in the area fraction of nucleoli per unit area of nucleus or of mitochondria, Golgi, or lysosomes was seen in either subpopulation at any passage level. Dilated cisternae of rough endoplasmic reticulum in early-passage cells were seen if cells were harvested with trypsin and fixed either before or after centrifugation, but were not seen in labeled or unlabeled cells from any passage level when cultures were fixed in situ. We conclude that a significant increase in cell size is the only significant morphological change associated with the loss of proliferative capacity of IRM-90 fibroblasts. Furthermore, our data indicate that there is no accumulation of secondary lysosomes in human diploid fibroblasts during aging in vitro; we therefore cannot support any hypothesis of aging or proliferative decline that is based mechanistically upon this phenomenon

Localization of high affinity [3H]glycine transport sites in the cerebellar cortex

International Nuclear Information System (INIS)

Wilkin, G.P.; Csillag, A.; Balazs, R.; Kingsbury, A.E.; Wilson, J.E.; Johnson, A.L.

1981-01-01

A study was made of [ 3 H ]glycine uptake sites in a preparation greatly enriched in large pieces of the cerebellar glomeruli (glomerulus particles) and in morphologically well preserved slices of rat cerebellum. Electron microscopic autoradiography revealed that of the neurones in the cerebellar cortex only Golgi cells transported [ 3 H]glycine at the low concentration used. Glial cells also took up [ 3 H]glycine but to a lesser extent than the Golgi neurons. It was also confirmed that under comparable conditions Golgi cells transport [ 3 H]GABA. Kinetic studies utilizing the Golgi axon terminal-containing glomerulus particles showed that glycine is a weak non-competitive inhibitor of [ 3 H]GABA uptake (Ksub(i) over 600 μM vs the Ksub(t) of about 20 μM) and that GABA is an even weaker inhibitor of [ 3 H]glycine uptake. (Auth.)

Frozen history : limitations and possibilities of quantitative diffusion studies

NARCIS (Netherlands)

Mom, G.P.A.; Albert de la Bruhèze, A.A.; Oldenziel, R.

2009-01-01

In this contribution I have tried to show how quantitative methods can generate new questions and thus support historical research. It can be concluded that re ducing historical complexity through forcing reality into the shape of a diffusion curve does not seem to be the preferable strategy for

Study of dose effect relationship at low doses for non quantitative reactions of skin intestinal mucosa and lung

International Nuclear Information System (INIS)

Dutreix, J.; Wambersie, A.

1977-01-01

Most of the biological reactions observed in animal experiments or in clinical studies are non quantitative and they only allow assessing an inequality between the effects produced by different irradiations. The method used in non quantitative studies is actually based on the relative contribution of irreparable events and reparable to the cell killing. It provides for the cell population involved in non quantitative biological effects some data which can be expressed in term of a cell survival curve. Such data can be useful in Radiation therapy particularly for maximizing the difference between biological effects by a proper choice of the fraction size. The initial part of the cell survival curve, within the range of doses actually used appears to be a straight exponential. This should allow the extrapolation to very low doses in the range of interest to Radiation Protection

The renal quantitative scintillation camera study for determination of renal function

International Nuclear Information System (INIS)

Thompson, I.M. Jr.; Boineau, F.G.; Evans, B.B.; Schlegel, J.U.

1983-01-01

The renal quantitative scintillation camera study assesses glomerular filtration rate and effective renal plasma flow based upon renal uptake of 99mtechnetium-iron ascorbate and 131iodine-hippuran, respectively. The method was compared to inulin, para-aminohippuric acid and creatinine clearance studies in 7 normal subjects and 9 patients with various degrees of reduced renal function. The reproducibility of the technique was determined in 15 randomly selected pediatric patients. The values of glomerular filtration rate and effective renal plasma flow were not significantly different from those of inulin and para-aminohippuric acid studies. The reproducibility of the technique was comparable to that of inulin and para-aminohippuric acid studies. Patient acceptance of the technique is excellent and the cost is minimal. Renal morphology and excretory dynamics also are demonstrated. The technique is advocated as a clinical measure of renal function

Quantitative detection of caffeine in human skin by confocal Raman spectroscopy--A systematic in vitro validation study.

Science.gov (United States)

Franzen, Lutz; Anderski, Juliane; Windbergs, Maike

2015-09-01

For rational development and evaluation of dermal drug delivery, the knowledge of rate and extent of substance penetration into the human skin is essential. However, current analytical procedures are destructive, labor intense and lack a defined spatial resolution. In this context, confocal Raman microscopy bares the potential to overcome current limitations in drug depth profiling. Confocal Raman microscopy already proved its suitability for the acquisition of qualitative penetration profiles, but a comprehensive investigation regarding its suitability for quantitative measurements inside the human skin is still missing. In this work, we present a systematic validation study to deploy confocal Raman microscopy for quantitative drug depth profiling in human skin. After we validated our Raman microscopic setup, we successfully established an experimental procedure that allows correlating the Raman signal of a model drug with its controlled concentration in human skin. To overcome current drawbacks in drug depth profiling, we evaluated different modes of peak correlation for quantitative Raman measurements and offer a suitable operating procedure for quantitative drug depth profiling in human skin. In conclusion, we successfully demonstrate the potential of confocal Raman microscopy for quantitative drug depth profiling in human skin as valuable alternative to destructive state-of-the-art techniques. Copyright © 2015 Elsevier B.V. All rights reserved.

Quantitative contrast-enhanced mammography for contrast medium kinetics studies

Science.gov (United States)

Arvanitis, C. D.; Speller, R.

2009-10-01

Quantitative contrast-enhanced mammography, based on a dual-energy approach, aims to extract quantitative and temporal information of the tumour enhancement after administration of iodinated vascular contrast media. Simulations using analytical expressions and optimization of critical parameters essential for the development of quantitative contrast-enhanced mammography are presented. The procedure has been experimentally evaluated using a tissue-equivalent phantom and an amorphous silicon active matrix flat panel imager. The x-ray beams were produced by a tungsten target tube and spectrally shaped using readily available materials. Measurement of iodine projected thickness in mg cm-2 has been performed. The effect of beam hardening does not introduce nonlinearities in the measurement of iodine projected thickness for values of thicknesses found in clinical investigations. However, scattered radiation introduces significant deviations from slope equal to unity when compared with the actual iodine projected thickness. Scatter correction before the analysis of the dual-energy images provides accurate iodine projected thickness measurements. At 10% of the exposure used in clinical mammography, signal-to-noise ratios in excess of 5 were achieved for iodine projected thicknesses less than 3 mg cm-2 within a 4 cm thick phantom. For the extraction of temporal information, a limited number of low-dose images were used with the phantom incorporating a flow of iodinated contrast medium. The results suggest that spatial and temporal information of iodinated contrast media can be used to indirectly measure the tumour microvessel density and determine its uptake and washout from breast tumours. The proposed method can significantly improve tumour detection in dense breasts. Its application to perform in situ x-ray biopsy and assessment of the oncolytic effect of anticancer agents is foreseeable.

Quantitative Modeling of Landscape Evolution, Treatise on Geomorphology

NARCIS (Netherlands)

Temme, A.J.A.M.; Schoorl, J.M.; Claessens, L.F.G.; Veldkamp, A.; Shroder, F.S.

2013-01-01

This chapter reviews quantitative modeling of landscape evolution – which means that not just model studies but also modeling concepts are discussed. Quantitative modeling is contrasted with conceptual or physical modeling, and four categories of model studies are presented. Procedural studies focus

Quantitative Lymphoscintigraphy to Predict the Possibility of Lymphedema Development After Breast Cancer Surgery: Retrospective Clinical Study.

Science.gov (United States)

Kim, Paul; Lee, Ju Kang; Lim, Oh Kyung; Park, Heung Kyu; Park, Ki Deok

2017-12-01

To predict the probability of lymphedema development in breast cancer patients in the early post-operation stage, we investigated the ability of quantitative lymphoscintigraphic assessment. This retrospective study included 201 patients without lymphedema after unilateral breast cancer surgery. Lymphoscintigraphy was performed between 4 and 8 weeks after surgery to evaluate the lymphatic system in the early postoperative stage. Quantitative lymphoscintigraphy was performed using four methods: ratio of radiopharmaceutical clearance rate of the affected to normal hand; ratio of radioactivity of the affected to normal hand; ratio of radiopharmaceutical uptake rate of the affected to normal axilla (RUA); and ratio of radioactivity of the affected to normal axilla (RRA). During a 1-year follow-up, patients with a circumferential interlimb difference of 2 cm at any measurement location and a 200-mL interlimb volume difference were diagnosed with lymphedema. We investigated the difference in quantitative lymphoscintigraphic assessment between the non-lymphedema and lymphedema groups. Quantitative lymphoscintigraphic assessment revealed that the RUA and RRA were significantly lower in the lymphedema group than in the non-lymphedema group. After adjusting the model for all significant variables (body mass index, N-stage, T-stage, type of surgery, and type of lymph node surgery), RRA was associated with lymphedema (odds ratio=0.14; 95% confidence interval, 0.04-0.46; p=0.001). In patients in the early postoperative stage after unilateral breast cancer surgery, quantitative lymphoscintigraphic assessment can be used to predict the probability of developing lymphedema.

A study on framework for assessing limiting condition for operation(LCOs) quantitatively in a CANDU reactor

International Nuclear Information System (INIS)

Kang, Kyung Min

2003-02-01

Limiting conditions for operations define the allowed outage times and the actions to be taken if the repair cannot be completed within the AOT. Typically the actions required are plant shutdown. In situations where the risk associated with the action, i.e., the risk of plant shutdown given a failure in the safety system, may be substantial, a strategy is needed to control the risk implications. In this study the strategy is evaluated quantitatively using a tool of system dynamics. The strategic actions associated with LCO needs to be assessed dynamically. System dynamics technique is easy enough to be applied for quantitative assessment of LCO, where the system dynamics is an important factor in evaluating operational modes of nuclear power plants. The review on the improvements of overly conservative technical specification has been performed in this study. The VENSIM tool has been applied to evaluate quantitatively the LCO of the auxiliary feed water systems in the Wol-Sung nuclear power plant. A value of core damage frequency in PSA is used as risk measure. The analysis of both full power operation and shutdown operation has been compared for the value of the CDF. This study shows a plot of LCO full power operating and shutdown risks in term of core damage probability for failure of AFWS (auxiliary feedwater system). Obtaining a lower risk level in a stable mode, compared to the LCO operation alternative, is the principal motivation of going to full power operational mode or shutdown operational mode. A time dependent framework developed in this study has been applied to assess the LCO of the example problem and it is shown that it is very flexible in that it can be applied to assess LCO quantitatively under any operational context of the technical specifications. This study contributes risk informed regulation to enhance and optimize the LCO of previous technical specifications for CANDU through developing framework in application proposed in this methodology

Quantitative study on the significance of FR cycle. Interim report of JNC/CEA joint study on advanced technology R and D for nuclear energy

International Nuclear Information System (INIS)

Fiorini, G.L.; Shinoda, Yoshihiko; Kofuji, Hirohide; Hirao, Kazunori

2001-09-01

This study on quantitative study on significance of FR cycle was carried out under the agreement between JNC and CEA in the field of advanced technology R and D for nuclear energy. JNC has been developing the quantitative evaluation method to be constructed by combining Analytic Hierarchy Process (AHP) and Multi-Attribute Utility Theory (MAUT). CEA has been caring out the qualitative evaluation from expert judgement from viewpoint of sustainability such as the response to the energetic demand, the saving of the resources and the minimization of the environmental impact. (author)

A study of quantitative radiography for moisture content distributions in plant

International Nuclear Information System (INIS)

Kawabata, Y.; Hino, M.; Horie, T.

2003-01-01

Vacuum pre-cooling in cut flower or perishable vegetables industry are used for protecting from the deterioration of the perishables during transportation. Some improvements of the pre-cooling way, however, are required for a bruise in plant on the way of handling. Neutron radiography is suitable to detect and observe the bruise in plant, especially, moisture content distributions in leaves, flowers and stalks. Neutron spectrum in irradiation neutron beams is required for obtaining quantitative moisture contents in plant. The neutron spectrum measurements for determination of effective cross-section of water are carried out at CN-3 experimental hole of Kyoto University Reactor (KUR) by time of flight method. Moisture content distributions in leaves of chrysanthemum, before and after the vacuum pre-cooling are measured by cold neutron radiography at the experimental hole. The local decreases of moisture contents caused by a bruise on the surface of the leaves are measured quantitatively by the cold neutron radiography. The quantitative changes of the moisture content in the leaves are able to read out from the cold neutron radiography image. (M. Suetake)

Quantitation: clinical applications

International Nuclear Information System (INIS)

Britton, K.E.

1982-01-01

Single photon emission tomography may be used quantitatively if its limitations are recognized and quantitation is made in relation to some reference area on the image. Relative quantitation is discussed in outline in relation to the liver, brain and pituitary, thyroid, adrenals, and heart. (U.K.)

Developing quantitative tools for measuring aspects of prisonization

DEFF Research Database (Denmark)

Kjær Minke, Linda

2013-01-01

The article describes and discusses the preparation and completion of a quantitative study among prison officers and prisoners.......The article describes and discusses the preparation and completion of a quantitative study among prison officers and prisoners....

Studies of CTNNBL1 and FDFT1 variants and measures of obesity: analyses of quantitative traits and case-control studies in 18,014 Danes

DEFF Research Database (Denmark)

Andreasen, Camilla Helene; Mogensen, Mette Sloth; Borch-Johnsen, Knut

2009-01-01

of obesity-related quantitative traits, and case-control studies in large study samples of Danes. METHODS: The FDFT1 rs7001819, CTNNBL1 rs6013029 and rs6020846 were genotyped, using TaqMan allelic discrimination, in a combined study sample comprising 18,014 participants ascertained from; the population...... and a previous study. FDFT1 rs7001819 showed no association with obesity, neither when analysing quantitative traits nor when performing case-control studies of obesity.......). The most significantly associating variants within CTNNBL1 including rs6013029 and rs6020846 were additionally confirmed to associate with morbid obesity in a French Caucasian case-control sample. The aim of this study was to investigate the impact of these three variants on obesity, through analyses...

Qualitative to quantitative: linked trajectory of method triangulation in a study on HIV/AIDS in Goa, India.

Science.gov (United States)

Bailey, Ajay; Hutter, Inge

2008-10-01

With 3.1 million people estimated to be living with HIV/AIDS in India and 39.5 million people globally, the epidemic has posed academics the challenge of identifying behaviours and their underlying beliefs in the effort to reduce the risk of HIV transmission. The Health Belief Model (HBM) is frequently used to identify risk behaviours and adherence behaviour in the field of HIV/AIDS. Risk behaviour studies that apply HBM have been largely quantitative and use of qualitative methodology is rare. The marriage of qualitative and quantitative methods has never been easy. The challenge is in triangulating the methods. Method triangulation has been largely used to combine insights from the qualitative and quantitative methods but not to link both the methods. In this paper we suggest a linked trajectory of method triangulation (LTMT). The linked trajectory aims to first gather individual level information through in-depth interviews and then to present the information as vignettes in focus group discussions. We thus validate information obtained from in-depth interviews and gather emic concepts that arise from the interaction. We thus capture both the interpretation and the interaction angles of the qualitative method. Further, using the qualitative information gained, a survey is designed. In doing so, the survey questions are grounded and contextualized. We employed this linked trajectory of method triangulation in a study on the risk assessment of HIV/AIDS among migrant and mobile men. Fieldwork was carried out in Goa, India. Data come from two waves of studies, first an explorative qualitative study (2003), second a larger study (2004-2005), including in-depth interviews (25), focus group discussions (21) and a survey (n=1259). By employing the qualitative to quantitative LTMT we can not only contextualize the existing concepts of the HBM, but also validate new concepts and identify new risk groups.

The quantitative Morse theorem

OpenAIRE

Loi, Ta Le; Phien, Phan

2013-01-01

In this paper, we give a proof of the quantitative Morse theorem stated by {Y. Yomdin} in \\cite{Y1}. The proof is based on the quantitative Sard theorem, the quantitative inverse function theorem and the quantitative Morse lemma.

A Framework for Mixing Methods in Quantitative Measurement Development, Validation, and Revision: A Case Study

Science.gov (United States)

Luyt, Russell

2012-01-01

A framework for quantitative measurement development, validation, and revision that incorporates both qualitative and quantitative methods is introduced. It extends and adapts Adcock and Collier's work, and thus, facilitates understanding of quantitative measurement development, validation, and revision as an integrated and cyclical set of…

Quantitative Data Analysis--In the Graduate Curriculum

Science.gov (United States)

Albers, Michael J.

2017-01-01

A quantitative research study collects numerical data that must be analyzed to help draw the study's conclusions. Teaching quantitative data analysis is not teaching number crunching, but teaching a way of critical thinking for how to analyze the data. The goal of data analysis is to reveal the underlying patterns, trends, and relationships of a…

Quantitative analysis of basal dendritic tree of layer III pyramidal neurons in different areas of adult human frontal cortex

OpenAIRE

Zeba, Martina; Jovanov-Milošević, Nataša; Petanjek, Zdravko

2008-01-01

Istraživanja mozga u primata ukazala su na dominantnu ulogu kortiko-kortikalnih piramidnih neurona IIIc sloja u neurobiologiji spoznajnih funkcija. U ovom radu prikazujemo rezultate usporedbene kvantitativne analize morfologije dendritičkog stabla najvećih neurona sloja IIIc impregniranih Golgi metodom, između tri različite Brodmannove areje (BA) frontalnog režnja mozga odraslog čovjeka: primarna motorna BA4, asocijativna magnopiramidalna BA9, te obostrano, govorna Brocina BA45. Statističkom ...

Quantitative palynofacies analysis as a new tool to study transfers of fossil organic matter in recent terrestrial environments

Energy Technology Data Exchange (ETDEWEB)

Graz, Y.; Di-Giovanni, C. [Universite d' Orleans, Universite Francois Rabelais - Tours, CNRS/INSU, Institut des Sciences de la Terre d' Orleans - UMR 6113 Campus Geosciences, 1A, rue de la Ferollerie, 45071 Orleans cedex 2 (France); Copard, Y. [M2C, UMR 6143 CNRS/Universite de Rouen, place E. Blondel, Bat. Irese A, Universite de Rouen, 76821 Mont Saint Aignan Cedex (France); Laggoun-Defarge, F.; Boussafir, M.; Lallier-Verges, E.; Baillif, P.; Perdereau, L.; Simonneau, A. [Universite d' Orleans, Universite Francois Rabelais - Tours, CNRS/INSU, Institut des Sciences de la Terre d' Orleans - UMR 6113 Campus Geosciences, 1A, rue de la Ferollerie, 45071 Orleans cedex 2 (France)

2010-10-01

Classical palynofacies method, which consists of an organic concentrate microscopic qualitative observation after mineral phase dissolution, is commonly used in order to study sedimentary organic matter. In the present study we develop a new quantitative palynofacies method that allows organic particles mass concentrations to be determined in studied samples. This method was developed to help quantify the input of fossil organic matter (FOM) into modern environments as a result of sedimentary rocks weathering. Studied samples were collected from different pools, like bedrocks, weathering profiles, soils and riverine particles in an experimental watershed ''Le Laval''. This watershed overlying Callovo-Oxfordian marls (1 km{sup 2} in area) is located near Digne, Alpes-de-Haute-Provence, in France. In addition to palynofacies techniques, Rock-Eval 6 pyrolysis and Al{sub 2}O{sub 3} content measurements (inductively coupled plasma emission spectrometry) were carried out on the samples. Obtained results show that this quantitative palynofacies method is suitable for FOM studies in modern environments, and FOM particles are quantified in the different pools. Results also give evidence that FOM alteration depends on the type of weathering, but also on the kind of organic particles. Soil formation under vegetation, resulting from the (bio)chemical weathering, lead to fossil organic particles concentration losses that do not exceed 30%. Elsewhere, mechanical weathering appears extremely fast and has no qualitative or quantitative influence on the observed FOM particles, which feeds directly into riverine stocks. FOM appears to be very resistant to weathering processes, this highlights its occurrence into supergene pools and then into carbon cycle. Quantitative palynofacies analysis is a new method adapted to such study, but can also be applied to other palynological, paleoenvironmental or archeological studies. (author)

Lesion detection and quantitation of positron emission mammography

International Nuclear Information System (INIS)

Qi, Jinyi; Huesman, Ronald H.

2001-01-01

A Positron Emission Mammography (PEM) scanner dedicated to breast imaging is being developed at our laboratory. We have developed a list mode likelihood reconstruction algorithm for this scanner. Here we theoretically study the lesion detection and quantitation. The lesion detectability is studied theoretically using computer observers. We found that for the zero-order quadratic prior, the region of interest observer can achieve the performance of the prewhitening observer with a properly selected smoothing parameter. We also study the lesion quantitation using the test statistic of the region of interest observer. The theoretical expressions for the bias, variance, and ensemble mean squared error of the quantitation are derived. Computer simulations show that the theoretical predictions are in good agreement with the Monte Carlo results for both lesion detection and quantitation

Computational complexity a quantitative perspective

CERN Document Server

Zimand, Marius

2004-01-01

There has been a common perception that computational complexity is a theory of "bad news" because its most typical results assert that various real-world and innocent-looking tasks are infeasible. In fact, "bad news" is a relative term, and, indeed, in some situations (e.g., in cryptography), we want an adversary to not be able to perform a certain task. However, a "bad news" result does not automatically become useful in such a scenario. For this to happen, its hardness features have to be quantitatively evaluated and shown to manifest extensively. The book undertakes a quantitative analysis of some of the major results in complexity that regard either classes of problems or individual concrete problems. The size of some important classes are studied using resource-bounded topological and measure-theoretical tools. In the case of individual problems, the book studies relevant quantitative attributes such as approximation properties or the number of hard inputs at each length. One chapter is dedicated to abs...

A novel multi-walled carbon nanotube-based antibody conjugate for quantitative and semi-quantitative lateral flow assays.

Science.gov (United States)

Sun, Wenjuan; Hu, Xiaolong; Liu, Jia; Zhang, Yurong; Lu, Jianzhong; Zeng, Libo

2017-10-01

In this study, the multi-walled carbon nanotubes (MWCNTs) were applied in lateral flow strips (LFS) for semi-quantitative and quantitative assays. Firstly, the solubility of MWCNTs was improved using various surfactants to enhance their biocompatibility for practical application. The dispersed MWCNTs were conjugated with the methamphetamine (MET) antibody in a non-covalent manner and then manufactured into the LFS for the quantitative detection of MET. The MWCNTs-based lateral flow assay (MWCNTs-LFA) exhibited an excellent linear relationship between the values of test line and MET when its concentration ranges from 62.5 to 1500 ng/mL. The sensitivity of the LFS was evaluated by conjugating MWCNTs with HCG antibody and the MWCNTs conjugated method is 10 times more sensitive than the one conjugated with classical colloidal gold nanoparticles. Taken together, our data demonstrate that MWCNTs-LFA is a more sensitive and reliable assay for semi-quantitative and quantitative detection which can be used in forensic analysis.

A study on the quantitative evaluation of skin barrier function

Science.gov (United States)

Maruyama, Tomomi; Kabetani, Yasuhiro; Kido, Michiko; Yamada, Kenji; Oikaze, Hirotoshi; Takechi, Yohei; Furuta, Tomotaka; Ishii, Shoichi; Katayama, Haruna; Jeong, Hieyong; Ohno, Yuko

2015-03-01

We propose a quantitative evaluation method of skin barrier function using Optical Coherence Microscopy system (OCM system) with coherency of near-infrared light. There are a lot of skin problems such as itching, irritation and so on. It has been recognized skin problems are caused by impairment of skin barrier function, which prevents damage from various external stimuli and loss of water. To evaluate skin barrier function, it is a common strategy that they observe skin surface and ask patients about their skin condition. The methods are subjective judgements and they are influenced by difference of experience of persons. Furthermore, microscopy has been used to observe inner structure of the skin in detail, and in vitro measurements like microscopy requires tissue sampling. On the other hand, it is necessary to assess objectively skin barrier function by quantitative evaluation method. In addition, non-invasive and nondestructive measuring method and examination changes over time are needed. Therefore, in vivo measurements are crucial for evaluating skin barrier function. In this study, we evaluate changes of stratum corneum structure which is important for evaluating skin barrier function by comparing water-penetrated skin with normal skin using a system with coherency of near-infrared light. Proposed method can obtain in vivo 3D images of inner structure of body tissue, which is non-invasive and non-destructive measuring method. We formulate changes of skin ultrastructure after water penetration. Finally, we evaluate the limit of performance of the OCM system in this work in order to discuss how to improve the OCM system.

Quantitative Algebraic Reasoning

DEFF Research Database (Denmark)

Mardare, Radu Iulian; Panangaden, Prakash; Plotkin, Gordon

2016-01-01

We develop a quantitative analogue of equational reasoning which we call quantitative algebra. We define an equality relation indexed by rationals: a =ε b which we think of as saying that “a is approximately equal to b up to an error of ε”. We have 4 interesting examples where we have a quantitative...... equational theory whose free algebras correspond to well known structures. In each case we have finitary and continuous versions. The four cases are: Hausdorff metrics from quantitive semilattices; pWasserstein metrics (hence also the Kantorovich metric) from barycentric algebras and also from pointed...

Qualitative versus quantitative methods in psychiatric research.

Science.gov (United States)

Razafsha, Mahdi; Behforuzi, Hura; Azari, Hassan; Zhang, Zhiqun; Wang, Kevin K; Kobeissy, Firas H; Gold, Mark S

2012-01-01

Qualitative studies are gaining their credibility after a period of being misinterpreted as "not being quantitative." Qualitative method is a broad umbrella term for research methodologies that describe and explain individuals' experiences, behaviors, interactions, and social contexts. In-depth interview, focus groups, and participant observation are among the qualitative methods of inquiry commonly used in psychiatry. Researchers measure the frequency of occurring events using quantitative methods; however, qualitative methods provide a broader understanding and a more thorough reasoning behind the event. Hence, it is considered to be of special importance in psychiatry. Besides hypothesis generation in earlier phases of the research, qualitative methods can be employed in questionnaire design, diagnostic criteria establishment, feasibility studies, as well as studies of attitude and beliefs. Animal models are another area that qualitative methods can be employed, especially when naturalistic observation of animal behavior is important. However, since qualitative results can be researcher's own view, they need to be statistically confirmed, quantitative methods. The tendency to combine both qualitative and quantitative methods as complementary methods has emerged over recent years. By applying both methods of research, scientists can take advantage of interpretative characteristics of qualitative methods as well as experimental dimensions of quantitative methods.

Qualitative and Quantitative Approaches to the Study of Poverty: Taming the Tensions and Appreciating the Complementarities

Science.gov (United States)

Balarabe Kura, Sulaiman Y.

2012-01-01

There is a germane relationship between qualitative and quantitative approaches to social science research. The relationship is empirically and theoretically demonstrated by poverty researchers. The study of poverty, as argued in this article, is a study of both numbers and contextualities. This article provides a general overview of qualitative…

Cancer patients' needs during hospitalisation: a quantitative and qualitative study

Directory of Open Access Journals (Sweden)

Greco Margherita

2003-04-01

Full Text Available Abstract Background The evaluation of cancer patients needs, especially during that delicate period when they are hospitalized, allows the identification of those areas of care that require to be improved. Aims of the study were to evaluate the needs in cancer inpatients and to improve the understanding of the meanings of the needs expressed. Methods The study was conducted during a "sample day", with all the cancer patients involved having been hospitalized at the Istituto Nazionale Tumori of Milan (INT for at least 48 hours beforehand. The study was carried out using quantitative and qualitative methodologies. The quantitative part of the study consisted in making use of the Needs Evaluation Questionnaire (NEQ, a standardized questionnaire administered by the INT Psychology Unit members, supported by a group of volunteers from the Milan section of the Italian League Against Cancer. The aim of the qualitative part of the study, by semi-structured interviews conducted with a small sample of 8 hospitalized patients, was to improve our understanding of the meanings, implications of the needs directly described from the point of view of the patients. Such an approach determines the reasons and conditions of the dissatisfaction in the patient, and provides additional information for the planning of improvement interventions. Results Of the 224 eligible patients, 182 (81% completed the questionnaire. Four of the top five needs expressed by 40% or more of the responders concerned information needs (diagnosis, future conditions, dialogue with doctors, economic-insurance solutions related to the disease. Only one of the 5 was concerned with improved "hotel" services (bathrooms, meals, cleanliness. Qualitative analysis showed that the most expressed need (to receive more information on their future conditions has the meaning to know how their future life will be affected more than to know his/her actual prognosis. Conclusions Some of the needs which

[Self-perception of health care team leaders in Andalusia. A quantitative and qualitative study].

Science.gov (United States)

García-Romera, I; Danet, A; March-Cerdà, J C

To determine the perception and self-assessment on leadership among health care team leaders in Andalusia. Design: Exploratory descriptive study using quantitative and qualitative methodology, developed between 2013 and 2015, using a questionnaire and semi-structured interviews. Andalusia. All health managers from the Primary Care Management Units and Health Management Areas of the Departments of Paediatrics, Emergency and Internal Medicine, for the quantitative study. A purposive sample of 24 health managers was used for the qualitative study. Descriptive statistical study and bivariate analysis of comparison of means. Content analysis of the semi-structured interviews: Codification, category tree, and triangulation of results. The best self-assessment dimension relates to support, and the worst to considering oneself as a 'good leader'. The definition of a 'good leader' includes: Honesty, trust, and attitudes of good communication, closeness, appreciation, and reinforcement of the health team members. Different leadership styles were perceived. Main difficulties for leadership are related to the economic crisis and the management of personal conflicts. Health managers describe an adaptive leadership style, based on personal and professional support, and using communication as the main cohesive element for the team project. More studies on leaders' perspectives are important, in order to better understand their experiences, needs and expectations. Copyright © 2016 SECA. Publicado por Elsevier España, S.L.U. All rights reserved.

The preliminary study of quantitative evaluation of salivary gland function by dynamic imaging

International Nuclear Information System (INIS)

Han Chunqi; Li Yaming; Li Deshun; Wang Guoli; Bai Jingming; Luo Xigui

1999-01-01

Objective: To evaluate the function of salivary gland by quantitative dynamic imaging. Methods: In thirty normals and twenty patients with Sjogren's syndrome (SS), absorption rate (15 min) and excretion rate (30 min) were calculated using two quantitative software. Results: Parotid and submandibular absorption rates in normal subjects were (0.26 +- 0.09)% and (0.15 +- 0.08)%, respectively; those of SS patients were (0.07 +- 0.03)% and (0.05 +- 0.04)%, t = 5.3 and 4.1, both were P < 0.01. There were markedly relativity between the two groups (r = 0.85). Conclusions: Quantitative methods of analyzing salivary function is simple, sensitive, practical reliable for evaluating salivary function and also has important clinical significance

Energy Education: The Quantitative Voice

Science.gov (United States)

Wolfson, Richard

2010-02-01

A serious study of energy use and its consequences has to be quantitative. It makes little sense to push your favorite renewable energy source if it can't provide enough energy to make a dent in humankind's prodigious energy consumption. Conversely, it makes no sense to dismiss alternatives---solar in particular---that supply Earth with energy at some 10,000 times our human energy consumption rate. But being quantitative---especially with nonscience students or the general public---is a delicate business. This talk draws on the speaker's experience presenting energy issues to diverse audiences through single lectures, entire courses, and a textbook. The emphasis is on developing a quick, ``back-of-the-envelope'' approach to quantitative understanding of energy issues. )

Comparison of clinical semi-quantitative assessment of muscle fat infiltration with quantitative assessment using chemical shift-based water/fat separation in MR studies of the calf of post-menopausal women.

Science.gov (United States)

Alizai, Hamza; Nardo, Lorenzo; Karampinos, Dimitrios C; Joseph, Gabby B; Yap, Samuel P; Baum, Thomas; Krug, Roland; Majumdar, Sharmila; Link, Thomas M

2012-07-01

The goal of this study was to compare the semi-quantitative Goutallier classification for fat infiltration with quantitative fat-fraction derived from a magnetic resonance imaging (MRI) chemical shift-based water/fat separation technique. Sixty-two women (age 61 ± 6 years), 27 of whom had diabetes, underwent MRI of the calf using a T1-weighted fast spin-echo sequence and a six-echo spoiled gradient-echo sequence at 3 T. Water/fat images and fat fraction maps were reconstructed using the IDEAL algorithm with T2* correction and a multi-peak model for the fat spectrum. Two radiologists scored fat infiltration on the T1-weighted images using the Goutallier classification in six muscle compartments. Spearman correlations between the Goutallier grades and the fat fraction were calculated; in addition, intra-observer and inter-observer agreement were calculated. A significant correlation between the clinical grading and the fat fraction values was found for all muscle compartments (P infiltration of muscle commonly occurs in many metabolic and neuromuscular diseases. • Image-based semi-quantitative classifications for assessing fat infiltration are not well validated. • Quantitative MRI techniques provide an accurate assessment of muscle fat.

Idiopathic normal pressure hydrocephalus, quantitative EEG findings, and the cerebrospinal fluid tap test: a pilot study.

Science.gov (United States)

Seo, Jong-Geun; Kang, Kyunghun; Jung, Ji-Young; Park, Sung-Pa; Lee, Maan-Gee; Lee, Ho-Won

2014-12-01

In this pilot study, we analyzed relationships between quantitative EEG measurements and clinical parameters in idiopathic normal pressure hydrocephalus patients, along with differences in these quantitative EEG markers between cerebrospinal fluid tap test responders and nonresponders. Twenty-six idiopathic normal pressure hydrocephalus patients (9 cerebrospinal fluid tap test responders and 17 cerebrospinal fluid tap test nonresponders) constituted the final group for analysis. The resting EEG was recorded and relative powers were computed for seven frequency bands. Cerebrospinal fluid tap test nonresponders, when compared with responders, showed a statistically significant increase in alpha2 band power at the right frontal and centrotemporal regions. Higher delta2 band powers in the frontal, central, parietal, and occipital regions and lower alpha1 band powers in the right temporal region significantly correlated with poorer cognitive performance. Higher theta1 band powers in the left parietal and occipital regions significantly correlated with gait dysfunction. And higher delta1 band powers in the right frontal regions significantly correlated with urinary disturbance. Our findings may encourage further research using quantitative EEG in patients with ventriculomegaly as a potential electrophysiological marker for predicting cerebrospinal fluid tap test responders. This study additionally suggests that the delta, theta, and alpha bands are statistically correlated with the severity of symptoms in idiopathic normal pressure hydrocephalus patients.

GPR107, a G-protein-coupled receptor essential for intoxication by Pseudomonas aeruginosa exotoxin A, localizes to the Golgi and is cleaved by furin.

Science.gov (United States)

Tafesse, Fikadu G; Guimaraes, Carla P; Maruyama, Takeshi; Carette, Jan E; Lory, Stephen; Brummelkamp, Thijn R; Ploegh, Hidde L

2014-08-29

A number of toxins, including exotoxin A (PE) of Pseudomonas aeruginosa, kill cells by inhibiting protein synthesis. PE kills by ADP-ribosylation of the translation elongation factor 2, but many of the host factors required for entry, membrane translocation, and intracellular transport remain to be elucidated. A genome-wide genetic screen in human KBM7 cells was performed to uncover host factors used by PE, several of which were confirmed by CRISPR/Cas9-gene editing in a different cell type. Several proteins not previously implicated in the PE intoxication pathway were identified, including GPR107, an orphan G-protein-coupled receptor. GPR107 localizes to the trans-Golgi network and is essential for retrograde transport. It is cleaved by the endoprotease furin, and a disulfide bond connects the two cleaved fragments. Compromising this association affects the function of GPR107. The N-terminal region of GPR107 is critical for its biological function. GPR107 might be one of the long-sought receptors that associates with G-proteins to regulate intracellular vesicular transport. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Quantitative sexing (Q-Sexing) and relative quantitative sexing (RQ ...

African Journals Online (AJOL)

samer

Key words: Polymerase chain reaction (PCR), quantitative real time polymerase chain reaction (qPCR), quantitative sexing, Siberian tiger. INTRODUCTION. Animal molecular sexing .... 43:3-12. Ellegren H (1996). First gene on the avian W chromosome (CHD) provides a tag for universal sexing of non-ratite birds. Proc.

A relative quantitative assessment of myocardial perfusion by first-pass technique: animal study

Science.gov (United States)

Chen, Jun; Zhang, Zhang; Yu, Xuefang; Zhou, Kenneth J.

2015-03-01

The purpose of this study is to quantitatively assess the myocardial perfusion by first-pass technique in swine model. Numerous techniques based on the analysis of Computed Tomography (CT) Hounsfield Unit (HU) density have emerged. Although these methods proposed to be able to assess haemodynamically significant coronary artery stenosis, their limitations are noticed. There are still needs to develop some new techniques. Experiments were performed upon five (5) closed-chest swine. Balloon catheters were placed into the coronary artery to simulate different degrees of luminal stenosis. Myocardial Blood Flow (MBF) was measured using color microsphere technique. Fractional Flow Reserve (FFR) was measured using pressure wire. CT examinations were performed twice during First-pass phase under adenosine-stress condition. CT HU Density (HUDCT) and CT HU Density Ratio (HUDRCT) were calculated using the acquired CT images. Our study presents that HUDRCT shows a good (y=0.07245+0.09963x, r2=0.898) correlation with MBF and FFR. In receiver operating characteristic (ROC) curve analyses, HUDRCT provides excellent diagnostic performance for the detection of significant ischemia during adenosine-stress as defined by FFR indicated by the value of Area Under the Curve (AUC) of 0.927. HUDRCT has the potential to be developed as a useful indicator of quantitative assessment of myocardial perfusion.

From themes to hypotheses: following up with quantitative methods.

Science.gov (United States)

Morgan, David L

2015-06-01

One important category of mixed-methods research designs consists of quantitative studies that follow up on qualitative research. In this case, the themes that serve as the results from the qualitative methods generate hypotheses for testing through the quantitative methods. That process requires operationalization to translate the concepts from the qualitative themes into quantitative variables. This article illustrates these procedures with examples that range from simple operationalization to the evaluation of complex models. It concludes with an argument for not only following up qualitative work with quantitative studies but also the reverse, and doing so by going beyond integrating methods within single projects to include broader mutual attention from qualitative and quantitative researchers who work in the same field. © The Author(s) 2015.

Comparison of clinical semi-quantitative assessment of muscle fat infiltration with quantitative assessment using chemical shift-based water/fat separation in MR studies of the calf of post-menopausal women

Energy Technology Data Exchange (ETDEWEB)

Alizai, Hamza; Nardo, Lorenzo; Karampinos, Dimitrios C.; Joseph, Gabby B.; Yap, Samuel P.; Baum, Thomas; Krug, Roland; Majumdar, Sharmila; Link, Thomas M. [University of California, San Francisco, Musculoskeletal and Quantitative Imaging Research Group, Department of Radiology and Biomedical Imaging, San Francisco, CA (United States)

2012-07-15

The goal of this study was to compare the semi-quantitative Goutallier classification for fat infiltration with quantitative fat-fraction derived from a magnetic resonance imaging (MRI) chemical shift-based water/fat separation technique. Sixty-two women (age 61 {+-} 6 years), 27 of whom had diabetes, underwent MRI of the calf using a T1-weighted fast spin-echo sequence and a six-echo spoiled gradient-echo sequence at 3 T. Water/fat images and fat fraction maps were reconstructed using the IDEAL algorithm with T2* correction and a multi-peak model for the fat spectrum. Two radiologists scored fat infiltration on the T1-weighted images using the Goutallier classification in six muscle compartments. Spearman correlations between the Goutallier grades and the fat fraction were calculated; in addition, intra-observer and inter-observer agreement were calculated. A significant correlation between the clinical grading and the fat fraction values was found for all muscle compartments (P < 0.0001, R values ranging from 0.79 to 0.88). Goutallier grades 0-4 had a fat fraction ranging from 3.5 to 19%. Intra-observer and inter-observer agreement values of 0.83 and 0.81 were calculated for the semi-quantitative grading. Semi-quantitative grading of intramuscular fat and quantitative fat fraction were significantly correlated and both techniques had excellent reproducibility. However, the clinical grading was found to overestimate muscle fat. (orig.)

Identification of rice cornichon as a possible cargo receptor for the Golgi-localized sodium transporter OsHKT1;3

Science.gov (United States)

Rosas-Santiago, Paul; Lagunas-Gómez, Daniel; Barkla, Bronwyn J.; Vera-Estrella, Rosario; Lalonde, Sylvie; Jones, Alexander; Frommer, Wolf B.; Zimmermannova, Olga; Sychrová, Hana; Pantoja, Omar

2015-01-01

Membrane proteins are synthesized and folded in the endoplasmic reticulum (ER), and continue their path to their site of residence along the secretory pathway. The COPII system has been identified as a key player for selecting and directing the fate of membrane and secretory cargo proteins. Selection of cargo proteins within the COPII vesicles is achieved by cargo receptors. The cornichon cargo receptor belongs to a conserved protein family found in eukaryotes that has been demonstrated to participate in the selection of integral membrane proteins as cargo for their correct targeting. Here it is demonstrated at the cellular level that rice cornichon OsCNIH1 interacts with OsHKT1;3 and, in yeast cells, enables the expression of the sodium transporter to the Golgi apparatus. Physical and functional HKT–cornichon interactions are confirmed by the mating-based split ubiquitin system, bimolecular fluorescence complementation, and Xenopus oocyte and yeast expression systems. The interaction between the two proteins occurs in the ER of plant cells and their co-expression in oocytes leads to the sequestration of the transporter in the ER. In the yeast cornichon mutant erv14, OsHKT1;3 is mistargeted, preventing the toxic effects of sodium transport in the cell observed in wild-type cells or in the erv14 mutant that co-expressed OsHKT1;3 with either OsCNIH1 or Erv14p. Identification and characterization of rice cornichon as a possible cargo receptor opens up the opportunity to improve our knowledge on membrane protein targeting in plant cells. PMID:25750424

Expermental Studies of quantitative evaluation using HPLC and safety of Sweet Bee Venom

OpenAIRE

Ki Rok Kwon; Ching Seng Chu; Hee Soo Park; Min Ki Kim; Bae Chun Cha; Eun Lee

2007-01-01

Objectives : This study was conducted to carry out quantitative evaluation and safety of Sweet Bee Venom. Methods : Content analysis was done using HPLC, measurement of LD50 was conducted intravenous, subcutaneous, and intra-muscular injection to the ICR mice. Results : 1. According to HPLC analysis, removal of the enzymes containing phospholipase A2 was successfully rendered on Sweet Bee Venom. And analyzing melittin content, Sweet Bee Venom contained 12% more melittin than Bee Venom. ...

Na+/K+-ATPase inhibition partially mimics the ethanol-induced increase of the Golgi cell-dependent component of the tonic GABAergic current in rat cerebellar granule cells.

Directory of Open Access Journals (Sweden)

Marvin R Diaz

Full Text Available Cerebellar granule cells (CGNs are one of many neurons that express phasic and tonic GABAergic conductances. Although it is well established that Golgi cells (GoCs mediate phasic GABAergic currents in CGNs, their role in mediating tonic currents in CGNs (CGN-I(tonic is controversial. Earlier studies suggested that GoCs mediate a component of CGN-I(tonic that is present only in preparations from immature rodents. However, more recent studies have detected a GoC-dependent component of CGN-I(tonic in preparations of mature rodents. In addition, acute exposure to ethanol was shown to potentiate the GoC component of CGN-I(tonic and to induce a parallel increase in spontaneous inhibitory postsynaptic current frequency at CGNs. Here, we tested the hypothesis that these effects of ethanol on GABAergic transmission in CGNs are mediated by inhibition of the Na(+/K(+-ATPase. We used whole-cell patch-clamp electrophysiology techniques in cerebellar slices of male rats (postnatal day 23-30. Under these conditions, we reliably detected a GoC-dependent component of CGN-I(tonic that could be blocked with tetrodotoxin. Further analysis revealed a positive correlation between basal sIPSC frequency and the magnitude of the GoC-dependent component of CGN-I(tonic. Inhibition of the Na(+/K(+-ATPase with a submaximal concentration of ouabain partially mimicked the ethanol-induced potentiation of both phasic and tonic GABAergic currents in CGNs. Modeling studies suggest that selective inhibition of the Na(+/K(+-ATPase in GoCs can, in part, explain these effects of ethanol. These findings establish a novel mechanism of action of ethanol on GABAergic transmission in the central nervous system.

A Primer on Disseminating Applied Quantitative Research

Science.gov (United States)

Bell, Bethany A.; DiStefano, Christine; Morgan, Grant B.

2010-01-01

Transparency and replication are essential features of scientific inquiry, yet scientific communications of applied quantitative research are often lacking in much-needed procedural information. In an effort to promote researchers dissemination of their quantitative studies in a cohesive, detailed, and informative manner, the authors delineate…

Quantitative analysis chemistry

International Nuclear Information System (INIS)

Ko, Wansuk; Lee, Choongyoung; Jun, Kwangsik; Hwang, Taeksung

1995-02-01

This book is about quantitative analysis chemistry. It is divided into ten chapters, which deal with the basic conception of material with the meaning of analysis chemistry and SI units, chemical equilibrium, basic preparation for quantitative analysis, introduction of volumetric analysis, acid-base titration of outline and experiment examples, chelate titration, oxidation-reduction titration with introduction, titration curve, and diazotization titration, precipitation titration, electrometric titration and quantitative analysis.

Quantitative research.

Science.gov (United States)

Watson, Roger

2015-04-01

This article describes the basic tenets of quantitative research. The concepts of dependent and independent variables are addressed and the concept of measurement and its associated issues, such as error, reliability and validity, are explored. Experiments and surveys – the principal research designs in quantitative research – are described and key features explained. The importance of the double-blind randomised controlled trial is emphasised, alongside the importance of longitudinal surveys, as opposed to cross-sectional surveys. Essential features of data storage are covered, with an emphasis on safe, anonymous storage. Finally, the article explores the analysis of quantitative data, considering what may be analysed and the main uses of statistics in analysis.

Quantitative film radiography

International Nuclear Information System (INIS)

Devine, G.; Dobie, D.; Fugina, J.; Hernandez, J.; Logan, C.; Mohr, P.; Moss, R.; Schumacher, B.; Updike, E.; Weirup, D.

1991-01-01

We have developed a system of quantitative radiography in order to produce quantitative images displaying homogeneity of parts. The materials that we characterize are synthetic composites and may contain important subtle density variations not discernible by examining a raw film x-radiograph. In order to quantitatively interpret film radiographs, it is necessary to digitize, interpret, and display the images. Our integrated system of quantitative radiography displays accurate, high-resolution pseudo-color images in units of density. We characterize approximately 10,000 parts per year in hundreds of different configurations and compositions with this system. This report discusses: the method; film processor monitoring and control; verifying film and processor performance; and correction of scatter effects

A Study on Quantitative Assessment of Design Specification of Reactor Protection System Software Using Bayesian Belief Networks

International Nuclear Information System (INIS)

Eom, H. S.; Kang, H. G.; Chang, S. C.; Park, G. Y.; Kwon, K. C.

2007-02-01

This report propose a method that can produce quantitative reliability of safety-critical software for PSA by making use of Bayesian Belief Networks (BBN). BBN has generally been used to model the uncertain system in many research fields. The proposed method was constructed by utilizing BBN that can combine the qualitative and the quantitative evidence relevant to the reliability of safety-critical software, and then can infer a conclusion in a formal and a quantitative way. A case study was also carried out with the proposed method to assess the quality of software design specification of safety-critical software that will be embedded in reactor protection system. The V and V results of the software were used as inputs for the BBN model. The calculation results of the BBN model showed that its conclusion is mostly equivalent to those of the V and V expert for a given input data set. The method and the results of the case study will be utilized in PSA of NPP. The method also can support the V and V expert's decision making process in controlling further V and V activities

Validating quantitative precipitation forecast for the Flood ...

Indian Academy of Sciences (India)

In order to issue an accurate warning for flood, a better or appropriate quantitative forecasting of precipitationis required. In view of this, the present study intends to validate the quantitative precipitationforecast (QPF) issued during southwest monsoon season for six river catchments (basin) under theflood meteorological ...

Quantitative SPECT reconstruction of iodine-123 data

International Nuclear Information System (INIS)

Gilland, D.R.; Jaszczak, R.J.; Greer, K.L.; Coleman, R.E.

1991-01-01

Many clinical and research studies in nuclear medicine require quantitation of iodine-123 ( 123 I) distribution for the determination of kinetics or localization. The objective of this study was to implement several reconstruction methods designed for single-photon emission computed tomography (SPECT) using 123 I and to evaluate their performance in terms of quantitative accuracy, image artifacts, and noise. The methods consisted of four attenuation and scatter compensation schemes incorporated into both the filtered backprojection/Chang (FBP) and maximum likelihood-expectation maximization (ML-EM) reconstruction algorithms. The methods were evaluated on data acquired of a phantom containing a hot sphere of 123 I activity in a lower level background 123 I distribution and nonuniform density media. For both reconstruction algorithms, nonuniform attenuation compensation combined with either scatter subtraction or Metz filtering produced images that were quantitatively accurate to within 15% of the true value. The ML-EM algorithm demonstrated quantitative accuracy comparable to FBP and smaller relative noise magnitude for all compensation schemes

An antibody toolkit for the study of membrane traffic in Drosophila melanogaster

Directory of Open Access Journals (Sweden)

Falko Riedel

2016-07-01

Full Text Available The use of Drosophila melanogaster as a model organism has been pivotal to understanding the developmental processes of metazoans. However, the use of flies for studying subcellular organization is hampered by a paucity of reliable reagents to label specific organelles. Here, we describe the generation of mouse monoclonal antibodies against a set of markers of the secretory and endocytic pathways, along with goat polyclonal antibodies against two Golgi proteins. We show that the monoclonal antibodies are highly specific and sufficiently sensitive to detect endogenous proteins in crude extracts by immunoblotting with little background staining. By immunofluorescence the major compartments of the membrane traffic system (including the endoplasmic reticulum, the Golgi, and early and late endosomes are labeled by at least one antibody. Moreover, the antibodies can be used to label organelles in fly tissues including salivary glands and wing imaginal discs. We anticipate that these antibodies will provide a useful tool kit to facilitate the investigation of how the endomembrane system functions and varies in the diverse tissue types of metazoans.

Assessment of precision and concordance of quantitative mitochondrial DNA assays: a collaborative international quality assurance study

NARCIS (Netherlands)

Hammond, Emma L.; Sayer, David; Nolan, David; Walker, Ulrich A.; Ronde, Anthony de; Montaner, Julio S. G.; Cote, Helene C. F.; Gahan, Michelle E.; Cherry, Catherine L.; Wesselingh, Steven L.; Reiss, Peter; Mallal, Simon

2003-01-01

Background: A number of international research groups have developed DNA quantitation assays in order to investigate the role of mitochondrial DNA depletion in anti-retroviral therapy-induced toxicities. Objectives: A collaborative study was undertaken to evaluate intra-assay precision and between

Quantitative Phase Imaging Techniques for the Study of Cell Pathophysiology: From Principles to Applications

Directory of Open Access Journals (Sweden)

Hyunjoo Park

2013-03-01

Full Text Available A cellular-level study of the pathophysiology is crucial for understanding the mechanisms behind human diseases. Recent advances in quantitative phase imaging (QPI techniques show promises for the cellular-level understanding of the pathophysiology of diseases. To provide important insight on how the QPI techniques potentially improve the study of cell pathophysiology, here we present the principles of QPI and highlight some of the recent applications of QPI ranging from cell homeostasis to infectious diseases and cancer.

Principals' perceptions on the practice of distributed leadership: a quantitative study

Directory of Open Access Journals (Sweden)

Ingrid del Valle García Carreño

2018-03-01

Full Text Available The aim of this paper is to describe distributed leadership practices (DLP in order to know the point of view of the directors of primary education centers of the Community of Madrid, Spain. It has been framed in a quantitative methodology, and a descriptive study, with a pilot test; also, it has been constructed and validated the ad hoc questionnaire "Distributed leadership practices of the Principal school", that allows collecting the perception that develops the directors (as in the context studied, and to know the relevance that they grant to them. The results found are very broad and correspond to the set of directors (as surveyed. This research presents the results of the DLP, which refers to the responses given by the group of school directors in one of the four dimensions (DLP, Shared Decisions, Mission, Vision and Professional Development.

Reproducibility of quantitative planar thallium-201 scintigraphy: quantitative criteria for reversibility of myocardial perfusion defects

International Nuclear Information System (INIS)

Sigal, S.L.; Soufer, R.; Fetterman, R.C.; Mattera, J.A.; Wackers, F.J.

1991-01-01

Fifty-two paired stress/delayed planar 201 TI studies (27 exercise studies, 25 dipyridamole studies) were processed twice by seven technologists to assess inter- and intraobserver variability. The reproducibility was inversely related to the size of 201 Tl perfusion abnormalities. Intraobserver variability was not different between exercise and dipyridamole studies for lesions of similar size. Based upon intraobserver variability, objective quantitative criteria for reversibility of perfusion abnormalities were defined. These objective criteria were tested prospectively in a separate group of 35 201 Tl studies and compared with the subjective interpretation of quantitative circumferential profiles. Overall, exact agreement existed in 78% of images (kappa statistic k = 0.66). We conclude that quantification of planar 201 Tl scans is highly reproducible, with acceptable inter- and intraobserver variability. Objective criteria for lesion reversibility correlated well with analysis by experienced observers

Comparative study of quantitative phase imaging techniques for refractometry of optical fibers

Science.gov (United States)

de Dorlodot, Bertrand; Bélanger, Erik; Bérubé, Jean-Philippe; Vallée, Réal; Marquet, Pierre

2018-02-01

The refractive index difference profile of optical fibers is the key design parameter because it determines, among other properties, the insertion losses and propagating modes. Therefore, an accurate refractive index profiling method is of paramount importance to their development and optimization. Quantitative phase imaging (QPI) is one of the available tools to retrieve structural characteristics of optical fibers, including the refractive index difference profile. Having the advantage of being non-destructive, several different QPI methods have been developed over the last decades. Here, we present a comparative study of three different available QPI techniques, namely the transport-of-intensity equation, quadriwave lateral shearing interferometry and digital holographic microscopy. To assess the accuracy and precision of those QPI techniques, quantitative phase images of the core of a well-characterized optical fiber have been retrieved for each of them and a robust image processing procedure has been applied in order to retrieve their refractive index difference profiles. As a result, even if the raw images for all the three QPI methods were suffering from different shortcomings, our robust automated image-processing pipeline successfully corrected these. After this treatment, all three QPI techniques yielded accurate, reliable and mutually consistent refractive index difference profiles in agreement with the accuracy and precision of the refracted near-field benchmark measurement.

Prediction of functional recovery after revascularization using quantitative gated myocardial perfusion SPECT: a multi-center cohort study in Japan

International Nuclear Information System (INIS)

Nakajima, Kenichi; Tamaki, Nagara; Kuwabara, Yoichi; Kawano, Masaya; Matsunari, Ichiro; Taki, Junichi; Nishimura, Shigeyuki; Yamashina, Akira; Ishida, Yoshio; Tomoike, Hitonobu

2008-01-01

Prediction of left ventricular functional recovery is important after myocardial infarction. The impact of quantitative perfusion and motion analyses with gated single-photon emission computed tomography (SPECT) on predictive ability has not been clearly defined in multi-center studies. A total of 252 patients with recent myocardial infarction (n = 74) and old myocardial infarction (n = 175) were registered from 25 institutions. All patients underwent resting gated SPECT using 99m Tc-hexakis-2-methoxy-isobutyl isonitrile (MIBI) and repeated the study after revascularization after an average follow-up period of 132 ± 81 days. Visual and quantitative assessment of perfusion and wall motion were performed in 5,040 segments. Non-gated segmental percent uptake and end-systolic (ES) percent uptake were good predictors of wall motion recovery and significantly differed between improved and non-improved groups (66 ± 17% and 55 ± 18%, p 99m Tc-MIBI uptake provided a useful predictor of wall motion improvement. Application of quantitative approach with non-gated and ES percent uptake enhanced predictive accuracy over visual analysis particularly in a multi-center study. (orig.)

Quantitative in situ magnetization reversal studies in Lorentz microscopy and electron holography

International Nuclear Information System (INIS)

Rodríguez, L.A.; Magén, C.; Snoeck, E.; Gatel, C.; Marín, L.; Serrano-Ramón, L.

2013-01-01

A generalized procedure for the in situ application of magnetic fields by means of the excitation of the objective lens for magnetic imaging experiments in Lorentz microscopy and electron holography is quantitatively described. A protocol for applying magnetic fields with arbitrary in-plane magnitude and orientation is presented, and a freeware script for Digital Micrograph ™ is provided to assist the operation of the microscope. Moreover, a method to accurately reconstruct hysteresis loops is detailed. We show that the out-of-plane component of the magnetic field cannot be always neglected when performing quantitative measurements of the local magnetization. Several examples are shown to demonstrate the accuracy and functionality of the methods. - Highlights: • Generalized procedure for application of magnetic fields with the TEM objective lens. • Arbitrary in-plane magnetic field magnitude and orientation can be applied. • Method to accurately reconstruct hysteresis loops by electron holography. • Out-of-plane field component should be considered in quantitative measurements. • Examples to illustrate the method in Lorentz microscopy and electron holography

Quantitative ion implantation

International Nuclear Information System (INIS)

Gries, W.H.

1976-06-01

This is a report of the study of the implantation of heavy ions at medium keV-energies into electrically conducting mono-elemental solids, at ion doses too small to cause significant loss of the implanted ions by resputtering. The study has been undertaken to investigate the possibility of accurate portioning of matter in submicrogram quantities, with some specific applications in mind. The problem is extensively investigated both on a theoretical level and in practice. A mathematical model is developed for calculating the loss of implanted ions by resputtering as a function of the implanted ion dose and the sputtering yield. Numerical data are produced therefrom which permit a good order-of-magnitude estimate of the loss for any ion/solid combination in which the ions are heavier than the solid atoms, and for any ion energy from 10 to 300 keV. The implanted ion dose is measured by integration of the ion beam current, and equipment and techniques are described which make possible the accurate integration of an ion current in an electromagnetic isotope separator. The methods are applied to two sample cases, one being a stable isotope, the other a radioisotope. In both cases independent methods are used to show that the implantation is indeed quantitative, as predicted. At the same time the sample cases are used to demonstrate two possible applications for quantitative ion implantation, viz. firstly for the manufacture of calibration standards for instrumental micromethods of elemental trace analysis in metals, and secondly for the determination of the half-lives of long-lived radioisotopes by a specific activity method. It is concluded that the present study has advanced quantitative ion implantation to the state where it can be successfully applied to the solution of problems in other fields

[Study on ethnic medicine quantitative reference herb,Tibetan medicine fruits of Capsicum frutescens as a case].

Science.gov (United States)

Zan, Ke; Cui, Gan; Guo, Li-Nong; Ma, Shuang-Cheng; Zheng, Jian

2018-05-01

High price and difficult to get of reference substance have become obstacles to HPLC assay of ethnic medicine. A new method based on quantitative reference herb (QRH) was proposed. Specific chromatograms in fruits of Capsicum frutescens were employed to determine peak positions, and HPLC quantitative reference herb was prepared from fruits of C. frutescens. The content of capsaicin and dihydrocapsaicin in the quantitative control herb was determined by HPLC. Eleven batches of fruits of C. frutescens were analyzed with quantitative reference herb and reference substance respectively. The results showed no difference. The present method is feasible for quality control of ethnic medicines and quantitative reference herb is suitable to replace reference substances in assay. Copyright© by the Chinese Pharmaceutical Association.

Relationship between Plaque Echo, Thickness and Neovascularization Assessed by Quantitative and Semi-quantitative Contrast-Enhanced Ultrasonography in Different Stenosis Groups.

Science.gov (United States)

Song, Yan; Feng, Jun; Dang, Ying; Zhao, Chao; Zheng, Jie; Ruan, Litao

2017-12-01

The aim of this study was to determine the relationship between plaque echo, thickness and neovascularization in different stenosis groups using quantitative and semi-quantitative contrast-enhanced ultrasound (CEUS) in patients with carotid atherosclerosis plaque. A total of 224 plaques were divided into mild stenosis (Quantitative and semi-quantitative methods were used to assess plaque neovascularization and determine the relationship between plaque echo, thickness and neovascularization. Correlation analysis revealed no relationship of neovascularization with plaque echo in the groups using either quantitative or semi-quantitative methods. Furthermore, there was no correlation of neovascularization with plaque thickness using the semi-quantitative method. The ratio of areas under the curve (RAUC) was negatively correlated with plaque thickness (r = -0.317, p = 0.001) in the mild stenosis group. With the quartile method, plaque thickness of the mild stenosis group was divided into four groups, with significant differences between the 1.5-2.2 mm and ≥3.5 mm groups (p = 0.002), 2.3-2.8 mm and ≥3.5 mm groups (p quantitative and quantitative CEUS methods characterizing neovascularization of plaque are equivalent with respect to assessing relationships between neovascularization, echogenicity and thickness. However, the quantitative method could fail for plaque <3.5 mm because of motion artifacts. Copyright © 2017 World Federation for Ultrasound in Medicine and Biology. Published by Elsevier Inc. All rights reserved.

The use of semi-structured interviews for collection of qualitative and quantitative data in hydrological studies

Science.gov (United States)

O'Keeffe, Jimmy; Buytaert, Wouter; Mijic, Ana; Brozovic, Nicholas

2015-04-01

To build an accurate, robust understanding of the environment, it is important to not only collect information describing its physical characteristics, but also the drivers which influence it. As environmental change, from increasing CO2 levels to decreasing water levels, is often heavily influenced by human activity, gathering information on anthropogenic as well as environmental variables is extremely important. This can mean collecting qualitative, as well as quantitative information. In reality studies are often bound by financial and time constraints, limiting the depth and detail of the research. It is up to the researcher to determine what the best methodology to answer the research questions is likely to be. Here we present a methodology of collecting qualitative and quantitative information in tandem for hydrological studies through the use of semi-structured interviews. This is applied to a case study in two districts of Uttar Pradesh, North India, one of the most intensely irrigated areas of the world. Here, decreasing water levels exacerbated by unchecked water abstraction, an expanding population and government subsidies, have put the long term resilience of the farming population in doubt. Through random selection of study locations, combined with convenience sampling of the participants therein, we show how the data collected can provide valuable insight into the drivers which have led to the current water scenario. We also show how reliable quantitative information can, using the same methodology, be effectively and efficiently extracted for modelling purposes, which along with developing an understanding of the characteristics of the environment is vital in coming up with realistic and sustainable solutions for water resource management in the future.

Quantitative structure-toxicity relationship study of some natural and synthetic coumarins using retention parameters

Directory of Open Access Journals (Sweden)

Rabtti El Hadi M.A.

2012-01-01

Full Text Available Four lipophilicity descriptors (RM0, b, C0, PC1 for twelve coumarine derivatives were determined by reversed-phase thin-layer chromatography in order to analyze which descriptor best describes the lipophilicity of coumarines investigated. Moreover, possible chemical toxicity of coumarins, expressed as the probability of a compound to cause organ-specific health effects, was calculated using ACD/Tox Suite program. The quantitative relationships between toxicity and molecular descriptors, including experimentally determined lipophilicity descriptors obtained in current study, were investigated using partial least square regression. The best models were obtained for kidney and liver health effects. Quantitative structure-toxicity relationship models revealed the importance of electric polarization descriptors, size descriptors and lipophilicity descriptors. Obtained models were used for the selection of the structural features of the compounds that are significantly affecting their absorption, distribution, metabolism, excretion, and toxicity. [Acknowledgements. This work has been supported by the Ministry of Education and Science of Serbia, Grant 172017.

A study on the qualitative and quantitative traits of barley (Hordeum ...

African Journals Online (AJOL)

user

Key words: Qualitative and quantitative, barley, narbon vetch, weed, dry land. ... and biomass production (Baishya and Sharma, 1990; ..... pakistan. Digitalverlag gmbh, germany. 157: 1-5. Pisulewska E, Hanczowski P, Pisulewski P (2003).

Quantitative study of magnetic field distribution by electron holography and micromagnetic simulations

International Nuclear Information System (INIS)

Beleggia, M.; Schofield, M.A.; Zhu, Y.; Malac, M.; Liu, Z.; Freeman, M.

2003-01-01

The magnetic configuration of a submicrometer Ni 88 Fe 12 permalloy island has been quantitatively mapped by off-axis electron holography. The two main contributions to the electron-optical phase shift, namely the phase shifts induced by the electrostatic and magnetic potentials, including fringing fields, were separated by inverting the specimen of 180 deg. with respect to the electron beam and directly measuring the mean inner potential. A quantitative map of the projected magnetic induction in the sample was thereby retrieved and compared to results of micromagnetic and electromagnetic calculations, providing the minimum-energy configuration and the phase shift, respectively

Rigour in quantitative research.

Science.gov (United States)

Claydon, Leica Sarah

2015-07-22

This article which forms part of the research series addresses scientific rigour in quantitative research. It explores the basis and use of quantitative research and the nature of scientific rigour. It examines how the reader may determine whether quantitative research results are accurate, the questions that should be asked to determine accuracy and the checklists that may be used in this process. Quantitative research has advantages in nursing, since it can provide numerical data to help answer questions encountered in everyday practice.

Quantitative study on lung volume and lung perfusion using SPECT and CT in thoracal tumors

International Nuclear Information System (INIS)

Beyer-Enke, S.A.; Goerich, J.; Strauss, L.G.

1988-01-01

22 patients with space occupying lesions in the thoracal region were investigated by computer tomography and by perfusion scintigraphy using SPECT. In order to evaluate the CT images quantitatively, the lung volume was determined using approximation method and compared with the perfusion in the SPECT study. For this, anatomically equivalent transaxial SPECT slices had been coordinated to the CT slices. Between the determined lung volumes and the activity in the ocrresponding layers, a statistically significant correlation was found. It could be shown that the stronger perfusion, frequently observed at the right side of the healthy lung, may be explained by an higher volume of the right pulmonary lobe. Whereas in benign displacing processes the relation activity to volume was similar to the one of the healthy lung, a strongly reduced perfusion together with inconspicuous lung volumes became apparent with malignant tumors. In addition to the great morphological evidence of CT and SPECT studies, additional informations regarding the dignity of displacing processes may be derived from the quantitative evaluation of both methods. (orig.) [de

Quantitative nature of overexpression experiments

Science.gov (United States)

Moriya, Hisao

2015-01-01

Overexpression experiments are sometimes considered as qualitative experiments designed to identify novel proteins and study their function. However, in order to draw conclusions regarding protein overexpression through association analyses using large-scale biological data sets, we need to recognize the quantitative nature of overexpression experiments. Here I discuss the quantitative features of two different types of overexpression experiment: absolute and relative. I also introduce the four primary mechanisms involved in growth defects caused by protein overexpression: resource overload, stoichiometric imbalance, promiscuous interactions, and pathway modulation associated with the degree of overexpression. PMID:26543202

Instrumentation and quantitative methods of evaluation

International Nuclear Information System (INIS)

Beck, R.N.; Cooper, M.D.

1991-01-01

This report summarizes goals and accomplishments of the research program entitled Instrumentation and Quantitative Methods of Evaluation, during the period January 15, 1989 through July 15, 1991. This program is very closely integrated with the radiopharmaceutical program entitled Quantitative Studies in Radiopharmaceutical Science. Together, they constitute the PROGRAM OF NUCLEAR MEDICINE AND QUANTITATIVE IMAGING RESEARCH within The Franklin McLean Memorial Research Institute (FMI). The program addresses problems involving the basic science and technology that underlie the physical and conceptual tools of radiotracer methodology as they relate to the measurement of structural and functional parameters of physiologic importance in health and disease. The principal tool is quantitative radionuclide imaging. The objective of this program is to further the development and transfer of radiotracer methodology from basic theory to routine clinical practice. The focus of the research is on the development of new instruments and radiopharmaceuticals, and the evaluation of these through the phase of clinical feasibility. 234 refs., 11 figs., 2 tabs

Progress towards in vitro quantitative imaging of human femur using compound quantitative ultrasonic tomography

International Nuclear Information System (INIS)

Lasaygues, Philippe; Ouedraogo, Edgard; Lefebvre, Jean-Pierre; Gindre, Marcel; Talmant, Marilyne; Laugier, Pascal

2005-01-01

The objective of this study is to make cross-sectional ultrasonic quantitative tomography of the diaphysis of long bones. Ultrasonic propagation in bones is affected by the severe mismatch between the acoustic properties of this biological solid and those of the surrounding soft medium, namely, the soft tissues in vivo or water in vitro. Bone imaging is then a nonlinear inverse-scattering problem. In this paper, we showed that in vitro quantitative images of sound velocities in a human femur cross section could be reconstructed by combining ultrasonic reflection tomography (URT), which provides images of the macroscopic structure of the bone, and ultrasonic transmission tomography (UTT), which provides quantitative images of the sound velocity. For the shape, we developed an image-processing tool to extract the external and internal boundaries and cortical thickness measurements. For velocity mapping, we used a wavelet analysis tool adapted to ultrasound, which allowed us to detect precisely the time of flight from the transmitted signals. A brief review of the ultrasonic tomography that we developed using correction algorithms of the wavepaths and compensation procedures are presented. Also shown are the first results of our analyses on models and specimens of long bone using our new iterative quantitative protocol

Beyond case studies: Quantitative effects of recycling, incentive, and diversion program choices

Energy Technology Data Exchange (ETDEWEB)

Skumatz, L.A. [Skumatz Economic Research Associates, Seattle, WA (United States)

1997-12-31

Communities, facing tight budgets, volatile markets, and the recycling backlash are turning their attention to making their programs more efficient and effective. Unfortunately, communities have very little quantitative information available to help them improve their programs. This is despite the fact that the majority of recycling programs have been running for over 6 years. Further, the author found that there are many thousands of curbside and dropoff recycling programs across the nation, as well as thousands of yard waste and variable rate programs. Still, with all these years of operating experience across the nation, at conferences, when planners ask about the likely impacts of possible program improvements, the answers usually begin, ``well, the City of [fill in the blank] made that change and found...``. Answers like this are seldom transferable to other communities. Similarly, most published information also relies on one or a few (less than ten) case studies, and published case studies usually describe programs that are outstanding in some way, making the information even less transferable. This type of information is wholly inadequate to derive information that is transferable to any other community. Can one really expect information from the City of San Jose, California, to transfer directly to the Village of Hartland, Wisconsin? That is the level of information that has been available thus far to planners. This study uses specially collected data from over 500 communities across North America as the basis for a statistical analysis of those programmatic and socio-demographic factors that contribute most to higher levels of recycling diversion. The work is unique in that it provides the first reliable quantitative information for use by community program planners in analyzing impacts of alternative programs and their cost-effectiveness to design sustainable, appropriate programs to improve diversion.

THE STUDY OF ORGANIZATIONAL CULTURE: METHODOLOGY FOR QUANTITATIVE EVALUATION AND ANALYSIS

Directory of Open Access Journals (Sweden)

To Thu Trang

2014-01-01

Full Text Available This article discusses the concept: methodof evaluation organizational culture, qualitative and quantitative assessment methodology and lists the basic methodologyfor assessing organizational culture. Fullydescribe professor Denison’s methodology for assessing organizational culture.

Gas chromatography-olfactometry and chemical quantitative study of the aroma of six premium quality spanish aged red wines.

Science.gov (United States)

Culleré, Laura; Escudero, Ana; Cacho, Juan; Ferreira, Vicente

2004-03-24

The aroma of six premium quality Spanish red wines has been studied by quantitative gas chromatography-olfactometry (GC-O) and techniques of quantitative chemical analysis. The GC-O study revealed the presence of 85 aromatic notes in which 78 odorants were identified, two of which-1-nonen-3-one (temptatively) and 2-acetylpyrazine-are reported in wine for the first time. Forty out of the 82 quantified odorants may be present at concentrations above their odor threshold. The components with the greatest capacity to introduce differences between these wines are ethyl phenols produced by Brettanomyces yeasts (4-ethylphenol, 4-ethyl-2-methoxyphenol, and 4-propyl-2-methoxyphenol), 2,5-dimethyl-4-hydroxy-3(2H)-furanone (furaneol), (Z)-3-hexenol, thiols derived from cysteinic precursors (4-methyl-4-mercaptopentan-2-one, 3-mercaptohexyl acetate, and 3-mercaptohexanol), some components yielded by the wood [(E)-isoeugenol, 4-allyl-2-methoxyphenol, vanillin, 2-methoxyphenol (guaiacol), and (Z)-whiskylactone], and compounds related to the metabolism (2-phenylethanol, ethyl esters of isoacids, 3-methylbutyl acetate) or oxidative degradation of amino acids [phenylacetaldehyde and 4,5-dimethyl-3-hydroxy-2(5H)-furanone (sotolon)]. The correlation between the olfactometric intensities and the quantitative data is, in general, satisfactory if olfactometric differences between the samples are high. However, GC-O fails in detecting quantitative differences in those cases in which the olfactive intensity is very high or if odors elute in areas in which the odor chromatogram is too complex.

Quantitative study on crack of meso-damage and fracture concrete ...

Indian Academy of Sciences (India)

1School of Civil Engineering, Chang'an University, Xi'an 710061, China. 2Institute of Geotechnical ... lysis of the meso-fracture process of concrete materials is performed. The results demonstrate that the ... realize the quantitative analysis of micro cracks of concrete material (Ammouche et al 2000). The whole CT images of ...

The golgin GMAP-210 is required for efficient membrane trafficking in the early secretory pathway.

Science.gov (United States)

Roboti, Peristera; Sato, Keisuke; Lowe, Martin

2015-04-15

Golgins are coiled-coil proteins that participate in membrane-tethering events at the Golgi complex. Golgin-mediated tethering is thought to be important for vesicular trafficking and Golgi organization. However, the degree to which individual golgins contribute to these processes is poorly defined, and it has been proposed that golgins act in a largely redundant manner. Previous studies on the golgin GMAP-210 (also known as TRIP11), which is mutated in the rare skeletal disorder achondrogenesis type 1A, have yielded conflicting results regarding its involvement in trafficking. Here, we re-investigated the trafficking role of GMAP-210, and found that it is indeed required for efficient trafficking in the secretory pathway. GMAP-210 acts at both the endoplasmic reticulum (ER)-to-Golgi intermediate compartment (ERGIC) and Golgi complex during anterograde trafficking, and is also required for retrograde trafficking to the ER. Using co-depletion experiments, we also found that GMAP-210 acts in a partially redundant manner with the golgin GM130 to ensure efficient anterograde cargo delivery to the cis-Golgi. In summary, our results indicate a role for GMAP-210 in several trafficking steps at the ER-Golgi interface, some of which are partially redundant with another golgin, namely GM130 (also known as GOLGA2). © 2015. Published by The Company of Biologists Ltd.

Quantitative investment analysis

CERN Document Server

DeFusco, Richard

2007-01-01

In the "Second Edition" of "Quantitative Investment Analysis," financial experts Richard DeFusco, Dennis McLeavey, Jerald Pinto, and David Runkle outline the tools and techniques needed to understand and apply quantitative methods to today's investment process.

Bringing quality and meaning to quantitative data - Bringing quantitative evidence to qualitative observation

DEFF Research Database (Denmark)

Karpatschof, Benny

2007-01-01

Based on the author's methodological theory defining the distinctive properties of quantitative and qualitative method the article demonstrates the possibilities and advantages of combining the two types of investigation in the same research project. The project being an effect study...

Cellular Protein WDR11 Interacts with Specific Herpes Simplex Virus Proteins at the trans-Golgi Network To Promote Virus Replication

Science.gov (United States)

Taylor, Kathryne E.

2015-01-01

ABSTRACT It has recently been proposed that the herpes simplex virus (HSV) protein ICP0 has cytoplasmic roles in blocking antiviral signaling and in promoting viral replication in addition to its well-known proteasome-dependent functions in the nucleus. However, the mechanisms through which it produces these effects remain unclear. While investigating this further, we identified a novel cytoplasmic interaction between ICP0 and the poorly characterized cellular protein WDR11. During an HSV infection, WDR11 undergoes a dramatic change in localization at late times in the viral replication cycle, moving from defined perinuclear structures to a dispersed cytoplasmic distribution. While this relocation was not observed during infection with viruses other than HSV-1 and correlated with efficient HSV-1 replication, the redistribution was found to occur independently of ICP0 expression, instead requiring viral late gene expression. We demonstrate for the first time that WDR11 is localized to the trans-Golgi network (TGN), where it interacts specifically with some, but not all, HSV virion components, in addition to ICP0. Knockdown of WDR11 in cultured human cells resulted in a modest but consistent decrease in yields of both wild-type and ICP0-null viruses, in the supernatant and cell-associated fractions, without affecting viral gene expression. Although further study is required, we propose that WDR11 participates in viral assembly and/or secondary envelopment. IMPORTANCE While the TGN has been proposed to be the major site of HSV-1 secondary envelopment, this process is incompletely understood, and in particular, the role of cellular TGN components in this pathway is unknown. Additionally, little is known about the cellular functions of WDR11, although the disruption of this protein has been implicated in multiple human diseases. Therefore, our finding that WDR11 is a TGN-resident protein that interacts with specific viral proteins to enhance viral yields improves both

Critical Quantitative Inquiry in Context

Science.gov (United States)

Stage, Frances K.; Wells, Ryan S.

2014-01-01

This chapter briefly traces the development of the concept of critical quantitative inquiry, provides an expanded conceptualization of the tasks of critical quantitative research, offers theoretical explanation and justification for critical research using quantitative methods, and previews the work of quantitative criticalists presented in this…

Study protocol: quantitative fibronectin to help decision-making in women with symptoms of preterm labour (QUIDS) part 2, UK Prospective Cohort Study

Science.gov (United States)

Wotherspoon, Lisa M; Boyd, Kathleen Anne; Morris, Rachel K; Jackson, Lesley; Chandiramani, Manju; David, Anna L; Khalil, Asma; Shennan, Andrew; Hodgetts Morton, Victoria; Lavender, Tina; Khan, Khalid; Harper-Clarke, Susan; Mol, Ben; Riley, Richard D; Norrie, John; Norman, Jane

2018-01-01

Introduction The aim of the QUIDS study is to develop a decision support tool for the management of women with symptoms and signs of preterm labour, based on a validated prognostic model using quantitative fetal fibronectin (fFN) concentration, in combination with clinical risk factors. Methods and analysis The study will evaluate the Rapid fFN 10Q System (Hologic, Marlborough, Massachusetts, USA) which quantifies fFN in a vaginal swab. In QUIDS part 2, we will perform a prospective cohort study in at least eight UK consultant-led maternity units, in women with symptoms of preterm labour at 22+0 to 34+6 weeks gestation to externally validate a prognostic model developed in QUIDS part 1. The effects of quantitative fFN on anxiety will be assessed, and acceptability of the test and prognostic model will be evaluated in a subgroup of women and clinicians (n=30). The sample size is 1600 women (with estimated 96–192 events of preterm delivery within 7 days of testing). Clinicians will be informed of the qualitative fFN result (positive/negative) but be blinded to quantitative fFN result. Research midwives will collect outcome data from the maternal and neonatal clinical records. The final validated prognostic model will be presented as a mobile or web-based application. Ethics and dissemination The study is funded by the National Institute of Healthcare Research Health Technology Assessment (HTA 14/32/01). It has been approved by the West of Scotland Research Ethics Committee (16/WS/0068). Version Protocol V.2, Date 1 November 2016. Trial registration number ISRCTN41598423 and CPMS: 31277. PMID:29674373

Yeast Interacting Proteins Database: YHL002W, YNR006W [Yeast Interacting Proteins Database

Lifescience Database Archive (English)

Full Text Available ycling of Golgi proteins and formation of lumenal membranes Rows with this bait as bait (1) Rows with this b...required for recycling Golgi proteins, forming lumenal membranes and sorting ubiquitinated proteins destined...on, as well as for recycling of Golgi proteins and formation of lumenal membranes...ith Hse1p; required for recycling Golgi proteins, forming lumenal membranes and sorting ubiquitinated protei

Yeast Interacting Proteins Database: YNR006W, YHL002W [Yeast Interacting Proteins Database

Lifescience Database Archive (English)

Full Text Available ling Golgi proteins, forming lumenal membranes and sorting ubiquitinated proteins destined for degradation; ..., as well as for recycling of Golgi proteins and formation of lumenal membranes Rows with this prey as prey ...1p; required for recycling Golgi proteins, forming lumenal membranes and sorting ubiquitinated proteins dest...degradation, as well as for recycling of Golgi proteins and formation of lumenal membranes

A Quantitative Study of the Relationship between Leadership Practice and Strategic Intentions to Use Cloud Computing

Science.gov (United States)

Castillo, Alan F.

2014-01-01

The purpose of this quantitative correlational cross-sectional research study was to examine a theoretical model consisting of leadership practice, attitudes of business process outsourcing, and strategic intentions of leaders to use cloud computing and to examine the relationships between each of the variables respectively. This study…

A Quantitative Comparative Study of Blended and Traditional Models in the Secondary Advanced Placement Statistics Classroom

Science.gov (United States)

Owens, Susan T.

2017-01-01

Technology is becoming an integral tool in the classroom and can make a positive impact on how the students learn. This quantitative comparative research study examined gender-based differences among secondary Advanced Placement (AP) Statistic students comparing Educational Testing Service (ETS) College Board AP Statistic examination scores…

Grid workflow validation using ontology-based tacit knowledge: A case study for quantitative remote sensing applications

Science.gov (United States)

Liu, Jia; Liu, Longli; Xue, Yong; Dong, Jing; Hu, Yingcui; Hill, Richard; Guang, Jie; Li, Chi

2017-01-01

Workflow for remote sensing quantitative retrieval is the ;bridge; between Grid services and Grid-enabled application of remote sensing quantitative retrieval. Workflow averts low-level implementation details of the Grid and hence enables users to focus on higher levels of application. The workflow for remote sensing quantitative retrieval plays an important role in remote sensing Grid and Cloud computing services, which can support the modelling, construction and implementation of large-scale complicated applications of remote sensing science. The validation of workflow is important in order to support the large-scale sophisticated scientific computation processes with enhanced performance and to minimize potential waste of time and resources. To research the semantic correctness of user-defined workflows, in this paper, we propose a workflow validation method based on tacit knowledge research in the remote sensing domain. We first discuss the remote sensing model and metadata. Through detailed analysis, we then discuss the method of extracting the domain tacit knowledge and expressing the knowledge with ontology. Additionally, we construct the domain ontology with Protégé. Through our experimental study, we verify the validity of this method in two ways, namely data source consistency error validation and parameters matching error validation.

A method to prioritize quantitative traits and individuals for sequencing in family-based studies.

Directory of Open Access Journals (Sweden)

Kaanan P Shah

Full Text Available Owing to recent advances in DNA sequencing, it is now technically feasible to evaluate the contribution of rare variation to complex traits and diseases. However, it is still cost prohibitive to sequence the whole genome (or exome of all individuals in each study. For quantitative traits, one strategy to reduce cost is to sequence individuals in the tails of the trait distribution. However, the next challenge becomes how to prioritize traits and individuals for sequencing since individuals are often characterized for dozens of medically relevant traits. In this article, we describe a new method, the Rare Variant Kinship Test (RVKT, which leverages relationship information in family-based studies to identify quantitative traits that are likely influenced by rare variants. Conditional on nuclear families and extended pedigrees, we evaluate the power of the RVKT via simulation. Not unexpectedly, the power of our method depends strongly on effect size, and to a lesser extent, on the frequency of the rare variant and the number and type of relationships in the sample. As an illustration, we also apply our method to data from two genetic studies in the Old Order Amish, a founder population with extensive genealogical records. Remarkably, we implicate the presence of a rare variant that lowers fasting triglyceride levels in the Heredity and Phenotype Intervention (HAPI Heart study (p = 0.044, consistent with the presence of a previously identified null mutation in the APOC3 gene that lowers fasting triglyceride levels in HAPI Heart study participants.

Quantitative assessment of myofibroblast in severe dysplasia, microinvasion and oral squamous cell carcinoma: an immunohistochemical study.

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Kapse, Sonam C; Rathod, Nanita; Baad, Rajendra; Mandlik, Jyoti; Sharma, Anupam S; Bommanavar, Sushma

2013-01-01

Myofibroblast are essential for the integrity of human body by virtue of its role in wound healing and pathological organ remodeling. Myofibroblast is a universal cellular component in mammalian lesions, but not a typical component of normal untraumatized tissues. Therefore its presence in abundance in case of cancer is a matter of concern. Tumor microenvironment plays a pivotal role in tumor progression. These so called cancer associated fibroblast or myofibroblast are the major components and occur in stromal tissue during carcinogenesis processes. This study is a quantitative assessment of presence and distribution of myofibroblast in severe dysplasia, microinvasion and oral squamous cell carcinoma (OSCC). Myofibroblast, Vimentin, α-SMA, OSCC, Severe dysplasia, Microinvasion. How to cite this article: Kapse SC, Rathod N, Baad R, Mandlik J, Sharma AS, Bommanavar S. Quantitative Assessment of Myofibroblast in Severe Dysplasia, Microinvasion and Oral Squamous Cell Carcinoma: An Immunohistochemical Study. J Contemp Dent Pract 2013;14(1):34-38. Source of support: Nil Conflict of interest: None declared.

Identification of rice cornichon as a possible cargo receptor for the Golgi-localized sodium transporter OsHKT1;3.

Science.gov (United States)

Rosas-Santiago, Paul; Lagunas-Gómez, Daniel; Barkla, Bronwyn J; Vera-Estrella, Rosario; Lalonde, Sylvie; Jones, Alexander; Frommer, Wolf B; Zimmermannova, Olga; Sychrová, Hana; Pantoja, Omar

2015-05-01

Membrane proteins are synthesized and folded in the endoplasmic reticulum (ER), and continue their path to their site of residence along the secretory pathway. The COPII system has been identified as a key player for selecting and directing the fate of membrane and secretory cargo proteins. Selection of cargo proteins within the COPII vesicles is achieved by cargo receptors. The cornichon cargo receptor belongs to a conserved protein family found in eukaryotes that has been demonstrated to participate in the selection of integral membrane proteins as cargo for their correct targeting. Here it is demonstrated at the cellular level that rice cornichon OsCNIH1 interacts with OsHKT1;3 and, in yeast cells, enables the expression of the sodium transporter to the Golgi apparatus. Physical and functional HKT-cornichon interactions are confirmed by the mating-based split ubiquitin system, bimolecular fluorescence complementation, and Xenopus oocyte and yeast expression systems. The interaction between the two proteins occurs in the ER of plant cells and their co-expression in oocytes leads to the sequestration of the transporter in the ER. In the yeast cornichon mutant erv14, OsHKT1;3 is mistargeted, preventing the toxic effects of sodium transport in the cell observed in wild-type cells or in the erv14 mutant that co-expressed OsHKT1;3 with either OsCNIH1 or Erv14p. Identification and characterization of rice cornichon as a possible cargo receptor opens up the opportunity to improve our knowledge on membrane protein targeting in plant cells. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Estudos quantitativos em educação Quantitative studies in education

Directory of Open Access Journals (Sweden)

Bernardete A. Gatti

2004-04-01

Full Text Available O artigo trata de estudos em educação, realizados no Brasil nas últimas três décadas, utilizando abordagens quantitativas. Para a seleção dos trabalhos a serem tratados fez-se um levantamento em todos os números publicados de 1970 para cá dos seguintes periódicos: Revista Brasileira de Estudos Pedagógicos (Inep/MEC, Cadernos de Pesquisa (Fundação Carlos Chagas, Educação e Realidade (UFRS, Educação e Sociedade (Cedes/Unicamp, Revista Brasileira de Educação (ANPEd, Estudos em Avaliação Educacional (Fundação Carlos Chagas, Ensaio (Fundação Cesgranrio. Algumas fontes bibliográficas foram consultadas na busca de outros estudos. Ressalta-se a importância de perspectivas teóricas para o delineamento e desenvolvimento dos estudos, que devem ser colocados no contexto de uma reflexão educacional e de problematização, bem como, assinala a necessidade de adequação das escolhas dos tipos de análise a serem empregados. Discute a pouca tradição de realização de trabalhos em educação com as metodologias quantitativas no Brasil e o possível papel da quantificação na pesquisa educacional. Mostra algumas contribuições desses trabalhos à reflexão no campo da Educação, bem como para a fundamentação de algumas perspectivas críticas. Essas contribuições foram tratadas por temas, a saber: analfabetismo, percurso escolar e fracasso escolar; fluxo escolar/análise de coortes; letramento; políticas e educação básica; financiamento da educação/municipalização; fatores sociais e educação; jovens e educação; avaliação educacional; temas variados.The article refers to studies in education carried out in Brazil during the last three decades using quantitative approaches. The selection of the works to be examined was based on a survey of all issues published since 1970 by the following journals: Revista Brasileira de Estudos Pedagógicos (Inep/MEC, Cadernos de Pesquisa (Fundação Carlos Chagas, Educação e

Accuracy of quantitative visual soil assessment

Science.gov (United States)

van Leeuwen, Maricke; Heuvelink, Gerard; Stoorvogel, Jetse; Wallinga, Jakob; de Boer, Imke; van Dam, Jos; van Essen, Everhard; Moolenaar, Simon; Verhoeven, Frank; Stoof, Cathelijne

2016-04-01

Visual soil assessment (VSA) is a method to assess soil quality visually, when standing in the field. VSA is increasingly used by farmers, farm organisations and companies, because it is rapid and cost-effective, and because looking at soil provides understanding about soil functioning. Often VSA is regarded as subjective, so there is a need to verify VSA. Also, many VSAs have not been fine-tuned for contrasting soil types. This could lead to wrong interpretation of soil quality and soil functioning when contrasting sites are compared to each other. We wanted to assess accuracy of VSA, while taking into account soil type. The first objective was to test whether quantitative visual field observations, which form the basis in many VSAs, could be validated with standardized field or laboratory measurements. The second objective was to assess whether quantitative visual field observations are reproducible, when used by observers with contrasting backgrounds. For the validation study, we made quantitative visual observations at 26 cattle farms. Farms were located at sand, clay and peat soils in the North Friesian Woodlands, the Netherlands. Quantitative visual observations evaluated were grass cover, number of biopores, number of roots, soil colour, soil structure, number of earthworms, number of gley mottles and soil compaction. Linear regression analysis showed that four out of eight quantitative visual observations could be well validated with standardized field or laboratory measurements. The following quantitative visual observations correlated well with standardized field or laboratory measurements: grass cover with classified images of surface cover; number of roots with root dry weight; amount of large structure elements with mean weight diameter; and soil colour with soil organic matter content. Correlation coefficients were greater than 0.3, from which half of the correlations were significant. For the reproducibility study, a group of 9 soil scientists and 7

Time-resolved quantitative phosphoproteomics

DEFF Research Database (Denmark)

Verano-Braga, Thiago; Schwämmle, Veit; Sylvester, Marc

2012-01-01

proteins involved in the Ang-(1-7) signaling, we performed a mass spectrometry-based time-resolved quantitative phosphoproteome study of human aortic endothelial cells (HAEC) treated with Ang-(1-7). We identified 1288 unique phosphosites on 699 different proteins with 99% certainty of correct peptide...

The Relationship between Shyness and Internet Addiction: A Quantitative Study on Middle and Post Secondary School Students

Science.gov (United States)

Hollingsworth, W. Craig

2005-01-01

This small scale quantitative study looks into the relationship between shyness and internet addiction in middle school students. This study has been conducted on the belief that shyness is a possible predictor of Internet Addiction. To prove this hypothesis a questionnaire was created and distributed to 53 middle school students and 159 post…

A QUANTITATIVE STUDY OF MARKET ORIENTATION AND ORGANIZATIONAL PERFORMANCE OF LISTED COMPANIES: EVIDENCE FROM GHANA

OpenAIRE

Solomon A. Keelson

2012-01-01

The study is part of a larger research of market orientation, which was conducted to build on previous research, and particularly examined the association between market orientation and business performance in a larger market context, using a synthesis model approach. Using the survey approach 24 companies out of 37 listed companies participated in the quantitative study; where 72 senior officials were surveyed from August 2011 to September 2011, through a five-likert scale questions. In this...

A multicrystal positron scanner for quantitative studies with positron-emitting radionuclides

International Nuclear Information System (INIS)

Ostertag, H.; Kuebler, W.; Kubesch, R.; Lorenz, W.J.

1981-01-01

A non-tomographic multicrystal whole-body scanner for quantitative positron imaging has been designed. The detector system consists of 64 coincidence detector pairs arranged in two opposing detector banks. NaI crystals of 38-mm diameter and 76-mm length are used. The patient moves linearly between the stationary transverse detector banks. The scanning area is 64-cm wide and up to 192-cm long. The spatial resolution is 2 cm at a sampling distance of 1 cm. The plane sensitivity amounts to 6400 counts/s for a pure positron emitter of 1 μCi/cm 2 . The accuracy of quantitative activity measurements is better than +- 15% for activities up to a few μCi/cm 2 . The design of the instrument, and its capabilities and limitations, are discussed. Initial experimental and clinical results are presented. (author)

Quantitative Susceptibility Mapping Indicates a Disturbed Brain Iron Homeostasis in Neuromyelitis Optica - A Pilot Study.

Directory of Open Access Journals (Sweden)

Thomas Martin Doring

Full Text Available Dysregulation of brain iron homeostasis is a hallmark of many neurodegenerative diseases and can be associated with oxidative stress. The objective of this study was to investigate brain iron in patients with Neuromyelitis Optica (NMO using quantitative susceptibility mapping (QSM, a quantitative iron-sensitive MRI technique. 12 clinically confirmed NMO patients (6 female and 6 male; age 35.4y±14.2y and 12 age- and sex-matched healthy controls (7 female and 5 male; age 33.9±11.3y underwent MRI of the brain at 3 Tesla. Quantitative maps of the effective transverse relaxation rate (R2* and magnetic susceptibility were calculated and a blinded ROI-based group comparison analysis was performed. Normality of the data and differences between patients and controls were tested by Kolmogorov-Smirnov and t-test, respectively. Correlation with age was studied using Spearman's rank correlation and an ANCOVA-like analysis. Magnetic susceptibility values were decreased in the red nucleus (p0.95; between -15 and -22 ppb depending on reference region with a trend toward increasing differences with age. R2* revealed significantly decreased relaxation in the optic radiations of five of the 12 patients (p<0.0001; -3.136±0.567 s-1. Decreased relaxation in the optic radiation is indicative for demyelination, which is in line with previous findings. Decreased magnetic susceptibility in the red nucleus is indicative for a lower brain iron concentration, a chemical redistribution of iron into less magnetic forms, or both. Further investigations are necessary to elucidate the pathological cause or consequence of this finding.

Using the realist perspective to link theory from qualitative evidence synthesis to quantitative studies: Broadening the matrix approach.

Science.gov (United States)

van Grootel, Leonie; van Wesel, Floryt; O'Mara-Eves, Alison; Thomas, James; Hox, Joop; Boeije, Hennie

2017-09-01

This study describes an approach for the use of a specific type of qualitative evidence synthesis in the matrix approach, a mixed studies reviewing method. The matrix approach compares quantitative and qualitative data on the review level by juxtaposing concrete recommendations from the qualitative evidence synthesis against interventions in primary quantitative studies. However, types of qualitative evidence syntheses that are associated with theory building generate theoretical models instead of recommendations. Therefore, the output from these types of qualitative evidence syntheses cannot directly be used for the matrix approach but requires transformation. This approach allows for the transformation of these types of output. The approach enables the inference of moderation effects instead of direct effects from the theoretical model developed in a qualitative evidence synthesis. Recommendations for practice are formulated on the basis of interactional relations inferred from the qualitative evidence synthesis. In doing so, we apply the realist perspective to model variables from the qualitative evidence synthesis according to the context-mechanism-outcome configuration. A worked example shows that it is possible to identify recommendations from a theory-building qualitative evidence synthesis using the realist perspective. We created subsets of the interventions from primary quantitative studies based on whether they matched the recommendations or not and compared the weighted mean effect sizes of the subsets. The comparison shows a slight difference in effect sizes between the groups of studies. The study concludes that the approach enhances the applicability of the matrix approach. Copyright © 2017 John Wiley & Sons, Ltd.

Using the realist perspective to link theory from qualitative evidence synthesis to quantitative studies: broadening the matrix approach.

NARCIS (Netherlands)

Grootel, L. van; Wesel, F. van; O'Mara-Eves, A.; Thomas, J.; Hox, J.; Boeije, H.

2017-01-01

Background: This study describes an approach for the use of a specific type of qualitative evidence synthesis in the matrix approach, a mixed studies reviewing method. The matrix approach compares quantitative and qualitative data on the review level by juxtaposing concrete recommendations from the

Quantitative study of flavonoids in leaves of citrus plants.

Science.gov (United States)

Kawaii, S; Tomono, Y; Katase, E; Ogawa, K; Yano, M; Koizumi, M; Ito, C; Furukawa, H

2000-09-01

Leaf flavonoids were quantitatively determined in 68 representative or economically important Citrus species, cultivars, and near-Citrus relatives. Contents of 23 flavonoids including 6 polymethoxylated flavones were analyzed by means of reversed phase HPLC analysis. Principal component analysis revealed that the 7 associations according to Tanaka's classification were observed, but some do overlap each other. Group VII species could be divided into two different subgroups, namely, the first-10-species class and the last-19-species class according to Tanaka's classification numbers.

Statistical correction of the Winner's Curse explains replication variability in quantitative trait genome-wide association studies.

Directory of Open Access Journals (Sweden)

Cameron Palmer

2017-07-01

Full Text Available Genome-wide association studies (GWAS have identified hundreds of SNPs responsible for variation in human quantitative traits. However, genome-wide-significant associations often fail to replicate across independent cohorts, in apparent inconsistency with their apparent strong effects in discovery cohorts. This limited success of replication raises pervasive questions about the utility of the GWAS field. We identify all 332 studies of quantitative traits from the NHGRI-EBI GWAS Database with attempted replication. We find that the majority of studies provide insufficient data to evaluate replication rates. The remaining papers replicate significantly worse than expected (p < 10-14, even when adjusting for regression-to-the-mean of effect size between discovery- and replication-cohorts termed the Winner's Curse (p < 10-16. We show this is due in part to misreporting replication cohort-size as a maximum number, rather than per-locus one. In 39 studies accurately reporting per-locus cohort-size for attempted replication of 707 loci in samples with similar ancestry, replication rate matched expectation (predicted 458, observed 457, p = 0.94. In contrast, ancestry differences between replication and discovery (13 studies, 385 loci cause the most highly-powered decile of loci to replicate worse than expected, due to difference in linkage disequilibrium.

Undergraduate Students' Quantitative Reasoning in Economic Contexts

Science.gov (United States)

Mkhatshwa, Thembinkosi Peter; Doerr, Helen M.

2018-01-01

Contributing to a growing body of research on undergraduate students' quantitative reasoning, the study reported in this article used task-based interviews to investigate business calculus students' quantitative reasoning when solving two optimization tasks situated in the context of revenue and profit maximization. Analysis of verbal responses…

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

International Nuclear Information System (INIS)

Sztul, E.S.

1984-01-01

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

Golga5 is dispensable for mouse embryonic development and postnatal survival.

Science.gov (United States)

McGee, Lynessa J; Jiang, Alex L; Lan, Yu

2017-07-01

Golgins are a family of coiled-coil proteins located at the cytoplasmic surface of the Golgi apparatus and have been implicated in maintaining Golgi structural integrity through acting as tethering factors for retrograde vesicle transport. Whereas knockdown of several individual golgins in cultured cells caused Golgi fragmentation and disruption of vesicle trafficking, analysis of mutant mouse models lacking individual golgins have discovered tissue-specific developmental functions. Recently, homozygous loss of function of GOLGA2, of which previous in vitro studies suggested an essential role in maintenance of Golgi structure and in mitosis, has been associated with a neuromuscular disorder in human patients, which highlights the need for understanding the developmental roles of the golgins in vivo. We report here generation of Golga5-deficient mice using CRISPR/Cas9-mediated genome editing. Although knockdown studies in cultured cells have implicated Golga5 in maintenance of Golgi organization, we show that Golga5 is not required for mouse embryonic development, postnatal survival, or fertility. Moreover, whereas Golga5 is structurally closely related to Golgb1, we show that inactivation of Golga5 does not enhance the severity of developmental defects in Golgb1-deficient mice. The Golga5-deficient mice enable further investigation of the roles and functional specificity of golgins in development and diseases. © 2017 Wiley Periodicals, Inc.

Mammographic features and subsequent risk of breast cancer: a comparison of qualitative and quantitative evaluations in the Guernsey prospective studies.

Science.gov (United States)