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Sample records for subcellular signalling compartments

  1. cAMP signaling in subcellular compartments.

    Science.gov (United States)

    Lefkimmiatis, Konstantinos; Zaccolo, Manuela

    2014-09-01

    In the complex microcosm of a cell, information security and its faithful transmission are critical for maintaining internal stability. To achieve a coordinated response of all its parts to any stimulus the cell must protect the information received from potentially confounding signals. Physical segregation of the information transmission chain ensures that only the entities able to perform the encoded task have access to the relevant information. The cAMP intracellular signaling pathway is an important system for signal transmission responsible for the ancestral 'flight or fight' response and involved in the control of critical functions including frequency and strength of heart contraction, energy metabolism and gene transcription. It is becoming increasingly apparent that the cAMP signaling pathway uses compartmentalization as a strategy for coordinating the large number of key cellular functions under its control. Spatial confinement allows the formation of cAMP signaling "hot spots" at discrete subcellular domains in response to specific stimuli, bringing the information in proximity to the relevant effectors and their recipients, thus achieving specificity of action. In this report we discuss how the different constituents of the cAMP pathway are targeted and participate in the formation of cAMP compartmentalized signaling events. We illustrate a few examples of localized cAMP signaling, with a particular focus on the nucleus, the sarcoplasmic reticulum and the mitochondria. Finally, we discuss the therapeutic potential of interventions designed to perturb specific cAMP cascades locally. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Lipidomics in tissues, cells and subcellular compartments

    National Research Council Canada - National Science Library

    Horn, Patrick J; Chapman, Kent D

    2012-01-01

    ...‐infusion MS, localization of lipids in tissues and cells by laser desorption/ionization MS, and even profiling of lipids in individual subcellular compartments by direct‐organelle MS. Applications of these approaches to achieve improved understanding of plant lipid metabolism, compartmentation and function are discussed.

  3. The Induction of Recombinant Protein Bodies in Different Subcellular Compartments Reveals a Cryptic Plastid-Targeting Signal in the 27-kDa γ-Zein Sequence.

    Science.gov (United States)

    Hofbauer, Anna; Peters, Jenny; Arcalis, Elsa; Rademacher, Thomas; Lampel, Johannes; Eudes, François; Vitale, Alessandro; Stoger, Eva

    2014-01-01

    Naturally occurring storage proteins such as zeins are used as fusion partners for recombinant proteins because they induce the formation of ectopic storage organelles known as protein bodies (PBs) where the proteins are stabilized by intermolecular interactions and the formation of disulfide bonds. Endogenous PBs are derived from the endoplasmic reticulum (ER). Here, we have used different targeting sequences to determine whether ectopic PBs composed of the N-terminal portion of mature 27 kDa γ-zein added to a fluorescent protein could be induced to form elsewhere in the cell. The addition of a transit peptide for targeting to plastids causes PB formation in the stroma, whereas in the absence of any added targeting sequence PBs were typically associated with the plastid envelope, revealing the presence of a cryptic plastid-targeting signal within the γ-zein cysteine-rich domain. The subcellular localization of the PBs influences their morphology and the solubility of the stored recombinant fusion protein. Our results indicate that the biogenesis and budding of PBs does not require ER-specific factors and therefore, confirm that γ-zein is a versatile fusion partner for recombinant proteins offering unique opportunities for the accumulation and bioencapsulation of recombinant proteins in different subcellular compartments.

  4. The induction of recombinant protein bodies in different subcellular compartments reveals a cryptic plastid-targeting signal in the 27 kD γ-zein sequence

    Directory of Open Access Journals (Sweden)

    Anna eHofbauer

    2014-12-01

    Full Text Available Naturally-occurring storage proteins such as zeins are used as fusion partners for recombinant proteins because they induce the formation of ectopic storage organelles known as protein bodies (PBs where the proteins are stabilized by intermolecular interactions and the formation of disulfide bonds. Endogenous PBs are derived from the endoplasmic reticulum (ER. Here we have used different targeting sequences to determine whether ectopic PBs composed of the N-terminal portion of mature 27 kD γ-zein added to a fluorescent protein could be induced to form elsewhere in the cell. The addition of a transit peptide for targeting to plastids causes PB formation in the stroma, whereas in the absence of any added targeting sequence PBs were typically associated with the plastid envelope, revealing the presence of a cryptic plastid targeting signal within the γ-zein cysteine-rich domain. The subcellular localization of the PBs influences their morphology and the solubility of the stored recombinant fusion protein. Our results indicate that the biogenesis and budding of PBs does not require ER-specific factors and therefore confirm that γ-zein is a versatile fusion partner for recombinant proteins offering unique opportunities for the accumulation and bioencapsulation of recombinant proteins in different subcellular compartments.

  5. Monoterpene biosynthesis potential of plant subcellular compartments

    NARCIS (Netherlands)

    Dong, L.; Jongedijk, E.J.; Bouwmeester, H.J.; Krol, van der A.R.

    2016-01-01

    Subcellular monoterpene biosynthesis capacity based on local geranyl diphosphate (GDP) availability or locally boosted GDP production was determined for plastids, cytosol and mitochondria. A geraniol synthase (GES) was targeted to plastids, cytosol, or mitochondria. Transient expression in Nicotiana

  6. Subcellular Organization of GPCR Signaling.

    Science.gov (United States)

    Eichel, Kelsie; von Zastrow, Mark

    2018-02-01

    G protein-coupled receptors (GPCRs) comprise a large and diverse class of signal-transducing receptors that undergo dynamic and isoform-specific membrane trafficking. GPCRs thus have an inherent potential to initiate or regulate signaling reactions from multiple membrane locations. This review discusses emerging insights into the subcellular organization of GPCR function in mammalian cells, focusing on signaling transduced by heterotrimeric G proteins and β-arrestins. We summarize recent evidence indicating that GPCR-mediated activation of G proteins occurs not only from the plasma membrane (PM) but also from endosomes and Golgi membranes and that β-arrestin-dependent signaling can be transduced from the PM by β-arrestin trafficking to clathrin-coated pits (CCPs) after dissociation from a ligand-activated GPCR. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Calculation of the relative metastabilities of proteins in subcellular compartments of Saccharomyces cerevisiae

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    Dick Jeffrey M

    2009-07-01

    Full Text Available Abstract Background Protein subcellular localization and differences in oxidation state between subcellular compartments are two well-studied features of the the cellular organization of S. cerevisiae (yeast. Theories about the origin of subcellular organization are assisted by computational models that can integrate data from observations of compositional and chemical properties of the system. Presentation and implications of the hypothesis I adopt the hypothesis that the state of yeast subcellular organization is in a local energy minimum. This hypothesis implies that equilibrium thermodynamic models can yield predictions about the interdependence between populations of proteins and their subcellular chemical environments. Testing the hypothesis Three types of tests are proposed. First, there should be correlations between modeled and observed oxidation states for different compartments. Second, there should be a correspondence between the energy requirements of protein formation and the order the appearance of organelles during cellular development. Third, there should be correlations between the predicted and observed relative abundances of interacting proteins within compartments. Results The relative metastability fields of subcellular homologs of glutaredoxin and thioredoxin indicate a trend from less to more oxidizing as mitochondrion – cytoplasm – nucleus. Representing the overall amino acid compositions of proteins in 23 different compartments each with a single reference model protein suggests that the formation reactions for proteins in the vacuole (in relatively oxidizing conditions, ER and early Golgi (in relatively reducing conditions are relatively highly favored, while that for the microtubule is the most costly. The relative abundances of model proteins for each compartment inferred from experimental data were found in some cases to correlate with the predicted abundances, and both positive and negative correlations were

  8. [Involvement of the endosomal compartment in cellular insulin signaling].

    Science.gov (United States)

    Desbuquois, Bernard; Authier, François

    2014-01-01

    The insulin receptor and insulin signaling proteins downstream the receptor reside in different subcellular compartments and undergo redistribution within the cell upon insulin activation. Endocytosis of the insulin-receptor complex, by mediating ligand degradation and receptor dephosphorylation, is generally viewed as a mechanism which attenuates or arrests insulin signal transduction. However, several observations suggest that insulin receptor endocytosis and/or recruitement of insulin signaling proteins to endosomes are also involved in a positive regulation of insulin signaling: (1) upon internalization, the insulin receptor remains transiently phosphorylated and activated; (2) in insulin-stimulated cells or tissues, signaling proteins of the PI3K/Akt and Ras/Raf/Mek/Erk pathways are recruited to endosomes or other intracellular compartments, in which they undergo phosphorylation and/or activation; and (3) depletion or overexpression of proteins involved in the regulation of membrane trafficking and endocytosis interfere with insulin signaling. These observations support a spatial and temporal regulation of insulin signal transduction and reinforce the concept that, as for other membrane signaling receptors, endocytosis and signaling are functionally linked. © Société de Biologie, 2014.

  9. Targeted Degradation of Proteins Localized in Subcellular Compartments by Hybrid Small Molecules.

    Science.gov (United States)

    Okuhira, Keiichiro; Shoda, Takuji; Omura, Risa; Ohoka, Nobumichi; Hattori, Takayuki; Shibata, Norihito; Demizu, Yosuke; Sugihara, Ryo; Ichino, Asato; Kawahara, Haruka; Itoh, Yukihiro; Ishikawa, Minoru; Hashimoto, Yuichi; Kurihara, Masaaki; Itoh, Susumu; Saito, Hiroyuki; Naito, Mikihiko

    2017-03-01

    Development of novel small molecules that selectively degrade pathogenic proteins would provide an important advance in targeted therapy. Recently, we have devised a series of hybrid small molecules named SNIPER (specific and nongenetic IAP-dependent protein ERaser) that induces the degradation of target proteins via the ubiquitin-proteasome system. To understand the localization of proteins that can be targeted by this protein knockdown technology, we examined whether SNIPER molecules are able to induce degradation of cellular retinoic acid binding protein II (CRABP-II) proteins localized in subcellular compartments of cells. CRABP-II is genetically fused with subcellular localization signals, and they are expressed in the cells. SNIPER(CRABP) with different IAP-ligands, SNIPER(CRABP)-4 with bestatin and SNIPER(CRABP)-11 with MV1 compound, induce the proteasomal degradation of wild-type (WT), cytosolic, nuclear, and membrane-localized CRABP-II proteins, whereas only SNIPER(CRABP)-11 displayed degradation activity toward the mitochondrial CRABP-II protein. The small interfering RNA-mediated silencing of cIAP1 expression attenuated the knockdown activity of SNIPER(CRABP) against WT and cytosolic CRABP-II proteins, indicating that cIAP1 is the E3 ligase responsible for degradation of these proteins. Against membrane-localized CRABP-II protein, cIAP1 is also a primary E3 ligase in the cells, but another E3 ligase distinct from cIAP2 and X-linked inhibitor of apoptosis protein (XIAP) could also be involved in the SNIPER(CRABP)-11-induced degradation. However, for the degradation of nuclear and mitochondrial CRABP-II proteins, E3 ligases other than cIAP1, cIAP2, and XIAP play a role in the SNIPER-mediated protein knockdown. These results indicate that SNIPER can target cytosolic, nuclear, membrane-localized, and mitochondrial proteins for degradation, but the responsible E3 ligase is different, depending on the localization of the target protein. Copyright © 2017 by

  10. Analytical model of ionization and energy deposition by proton beams in subcellular compartments

    Science.gov (United States)

    de Vera, Pablo; Surdutovich, Eugene; Abril, Isabel; Garcia-Molina, Rafael; Solov'yov, Andrey V.

    2014-04-01

    We present an analytical model to evaluate in a fast, simple and effective manner the energy delivered by proton beams moving through a cell model made of nucleus and cytoplasm, taking into account the energy carried by the secondary electrons generated along the proton tracks. The electronic excitation spectra of these subcellular compartments have been modelled by means of an empirical parameterization of their dielectric properties. The energy loss rate and target ionization probability induced by swift protons are evaluated by means of the dielectric formalism. With the present model we have quantified the energy delivered, the specific energy, and the number of ionizations produced per incoming ion in a typical human cell by a typical hadrontherapy proton beam having energies usually reached around the Bragg peak (below 20 MeV). We find that the specific energy per incoming ion delivered in the nucleus and in the cytoplasm are rather similar for all the proton energy range analyzed.

  11. Aeropyrum pernix membrane topology of protein VKOR promotes protein disulfide bond formation in two subcellular compartments.

    Science.gov (United States)

    Hibender, Stijntje; Landeta, Cristina; Berkmen, Mehmet; Beckwith, Jon; Boyd, Dana

    2017-11-15

    Disulfide bonds confer stability and activity to proteins. Bioinformatic approaches allow predictions of which organisms make protein disulfide bonds and in which subcellular compartments disulfide bond formation takes place. Such an analysis, along with biochemical and protein structural data, suggests that many of the extremophile Crenarachaea make protein disulfide bonds in both the cytoplasm and the cell envelope. We have sought to determine the oxidative folding pathways in the sequenced genomes of the Crenarchaea, by seeking homologues of the enzymes known to be involved in disulfide bond formation in bacteria. Some Crenarchaea have two homologues of the cytoplasmic membrane protein VKOR, a protein required in many bacteria for the oxidation of bacterial DsbAs. We show that the two VKORs of Aeropyrum pernix assume opposite orientations in the cytoplasmic membrane, when expressed in E. coli. One has its active cysteines oriented toward the E. coli periplasm (ApVKORo) and the other toward the cytoplasm (ApVKORi). Furthermore, the ApVKORo promotes disulfide bond formation in the E. coli cell envelope, while the ApVKORi promotes disulfide bond formation in the E. coli cytoplasm via a co-expressed archaeal protein ApPDO. Amongst the VKORs from different archaeal species, the pairs of VKORs in each species are much more closely related to each other than to the VKORs of the other species. The results suggest two independent occurrences of the evolution of the two topologically inverted VKORs in archaea. Our results suggest a mechanistic basis for the formation of disulfide bonds in the cytoplasm of Crenarchaea.

  12. Optimization of ruminococcus albus endoglucanase cel5-cbm6 production in plants by incorporating an elp tag and targeting to different subcellular compartments

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, E.O.; Menassa, R. [Western Ontario Univ., London, ON (Canada). Dept. of Biology; Agriculture and Agri-Food Canada, London, ON (Canada); Kolotilin, I. [Agriculture and Agri-Food Canada, London, ON (Canada)

    2009-07-01

    The production of biomass-based biofuel such as ethanol depends on the deconstruction of a cellulosic matrix and requires a variety of enzymes that hydrolyze glycosidic bonds to release fermentable sugars. Endoglucanases are one of most important groups of natural cellulosic hydrolytic enzymes that act on cellulose. In order to decrease ethanol production costs, the cost of producing cellulases must also be reduced. Genetically engineered transgenic plants are among the most economical systems for large scale production of recombinant proteins because of the large amount of enzymes that can be produced with minimal input. Cellulases present different levels of expression in different subcellular compartments. Cel5-CBM6 is a fused protein containing an endocellulase from Ruminococus albus (Cel5) and a cellulose binding domain (CBD) of Clostridium stercorarium. It accumulates in both the chloroplast and cytoplasm, but severe growth defects occur when expressed in the cytoplasm. Therefore, other subcellular compartments such as endoplasmic reticulum (ER) and vacuole must be evaluated and compared to determine the best co partment for production and activity of cellulases. Since elastin-like polypeptide (ELP) has also been shown to increase recombinant protein accumulation in plants, this study evaluated the effects of incorporating an ELP tag and a retrieval signal peptide on the expression levels of Cel5-CBM6.

  13. Arabinogalactan glycosyltransferases target to a unique subcellular compartment that may function in unconventional secretion in plants

    DEFF Research Database (Denmark)

    Poulsen, Christian Peter; Dilokpimol, Adiphol; Mouille, Grégory

    2014-01-01

    We report that fluorescently tagged arabinogalactan glycosyltransferases target not only the Golgi apparatus but also uncharacterized smaller compartments when transiently expressed in Nicotiana benthamiana. Approximately 80% of AtGALT31A [Arabidopsis thaliana galactosyltransferase from family 31......-glycosylation enzymes rarely colocalized (3-18%), implicating a role of the small compartments in a part of arabinogalactan (O-glycan) biosynthesis rather than N-glycan processing. The dual localization of AtGALT31A was also observed for fluorescently tagged AtGALT31A stably expressed in an Arabidopsis atgalt31a mutant...

  14. Multivariate profiling of neurodegeneration-associated changes in a subcellular compartment of neurons via image processing

    Directory of Open Access Journals (Sweden)

    Kumarasamy Saravana K

    2008-11-01

    Full Text Available Abstract Background Dysfunction in the endolysosome, a late endosomal to lysosomal degradative intracellular compartment, is an early hallmark of some neurodegenerative diseases, in particular Alzheimer's disease. However, the subtle morphological changes in compartments of affected neurons are difficult to quantify quickly and reliably, making this phenotype inaccessible as either an early diagnostic marker, or as a read-out for drug screening. Methods We present a method for automatic detection of fluorescently labeled endolysosomes in degenerative neurons in situ. The Drosophila blue cheese (bchs mutant was taken as a genetic neurodegenerative model for direct in situ visualization and quantification of endolysosomal compartments in affected neurons. Endolysosomal compartments were first detected automatically from 2-D image sections using a combination of point-wise multi-scale correlation and normalized correlation operations. This detection algorithm performed well at recognizing fluorescent endolysosomes, unlike conventional convolution methods, which are confounded by variable intensity levels and background noise. Morphological feature differences between endolysosomes from wild type vs. degenerative neurons were then quantified by multivariate profiling and support vector machine (SVM classification based on compartment density, size and contrast distribution. Finally, we ranked these distributions according to their profiling accuracy, based on the backward elimination method. Results This analysis revealed a statistically significant difference between the neurodegenerative phenotype and the wild type up to a 99.9% confidence interval. Differences between the wild type and phenotypes resulting from overexpression of the Bchs protein are detectable by contrast variations, whereas both size and contrast variations distinguish the wild type from either of the loss of function alleles bchs1 or bchs58. In contrast, the density measurement

  15. In vivo imaging of alpha-synuclein in mouse cortex demonstrates stable expression and differential subcellular compartment mobility.

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    Vivek K Unni

    2010-05-01

    Full Text Available Regulation of alpha-synuclein levels within cells is thought to play a critical role in Parkinson's Disease (PD pathogenesis and in other related synucleinopathies. These processes have been studied primarily in reduced preparations, including cell culture. We now develop methods to measure alpha-synuclein levels in the living mammalian brain to study in vivo protein mobility, turnover and degradation with subcellular specificity.We have developed a system using enhanced Green Fluorescent Protein (GFP-tagged human alpha-synuclein (Syn-GFP transgenic mice and in vivo multiphoton imaging to measure alpha-synuclein levels with subcellular resolution. This new experimental paradigm allows individual Syn-GFP-expressing neurons and presynaptic terminals to be imaged in the living mouse brain over a period of months. We find that Syn-GFP is stably expressed by neurons and presynaptic terminals over this time frame and further find that different presynaptic terminals can express widely differing levels of Syn-GFP. Using the fluorescence recovery after photobleaching (FRAP technique in vivo we provide evidence that at least two pools of Syn-GFP exist in terminals with lower levels of mobility than measured previously. These results demonstrate that multiphoton imaging in Syn-GFP mice is an excellent new strategy for exploring the biology of alpha-synuclein and related mechanisms of neurodegeneration.In vivo multiphoton imaging in Syn-GFP transgenic mice demonstrates stable alpha-synuclein expression and differential subcellular compartment mobility within cortical neurons. This opens new avenues for studying alpha-synuclein biology in the living brain and testing new therapeutics for PD and related disorders.

  16. Physiological intracellular crowdedness is defined by perimeter to area ratio of subcellular compartments

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    Noriko eHiroi

    2012-07-01

    Full Text Available The intracellular environment is known to be a crowded and inhomogeneous space. Such an in vivo environment differs from a well-diluted, homogeneous environment for biochemical reactions. However, the effects of both crowdedness and the inhomogeneity of environment on the behavior of a mobile particle have not yet been investigated sufficiently. As described in this paper, we constructed artificial reaction spaces with fractal models, which are assumed to be non-reactive solid obstacles in a reaction space with crevices that function as operating ranges for mobile particles threading the space. Because of the homogeneity of the structures of artificial reaction spaces, the models succeeded in reproducing the physiological fractal dimension of solid structures with a smaller number of non-reactive obstacles than in the physiological condition. This incomplete compatibility was mitigated when we chose a suitable condition of a perimeter-to-area ratio of the operating range to our model. Our results also show that a simulation space is partitioned into convenient reaction compartments as an in vivo environment with the exact amount of solid structures estimated from TEM images. The characteristics of these compartments engender larger mean square displacement of a mobile particle than that of particles in smaller compartments. Subsequently, the particles start to show confined particle-like behavior. These results are compatible with our previously presented results, which predicted that a physiological environment would produce quick-response and slow-exhaustion reactions.

  17. Predicting protein subcellular location using digital signal processing.

    Science.gov (United States)

    Pan, Yu-Xi; Li, Da-Wei; Duan, Yun; Zhang, Zhi-Zhou; Xu, Ming-Qing; Feng, Guo-Yin; He, Lin

    2005-02-01

    The biological functions of a protein are closely related to its attributes in a cell. With the rapid accumulation of newly found protein sequence data in databanks, it is highly desirable to develop an automated method for predicting the subcellular location of proteins. The establishment of such a predictor will expedite the functional determination of newly found proteins and the process of prioritizing genes and proteins identified by genomic efforts as potential molecular targets for drug design. The traditional algorithms for predicting these attributes were based solely on amino acid composition in which no sequence order effect was taken into account. To improve the prediction quality, it is necessary to incorporate such an effect. However, the number of possible patterns in protein sequences is extremely large, posing a formidable difficulty for realizing this goal. To deal with such difficulty, a well-developed tool in digital signal processing named digital Fourier transform (DFT) [1] was introduced. After being translated to a digital signal according to the hydrophobicity of each amino acid, a protein was analyzed by DFT within the frequency domain. A set of frequency spectrum parameters, thus obtained, were regarded as the factors to represent the sequence order effect. A significant improvement in prediction quality was observed by incorporating the frequency spectrum parameters with the conventional amino acid composition. One of the crucial merits of this approach is that many existing tools in mathematics and engineering can be easily applied in the predicting process. It is anticipated that digital signal processing may serve as a useful vehicle for many other protein science areas.

  18. Distinct redox regulation in sub-cellular compartments in response to various stress conditions in Saccharomyces cerevisiae.

    Science.gov (United States)

    Ayer, Anita; Sanwald, Julia; Pillay, Bethany A; Meyer, Andreas J; Perrone, Gabriel G; Dawes, Ian W

    2013-01-01

    Responses to many growth and stress conditions are assumed to act via changes to the cellular redox status. However, direct measurement of pH-adjusted redox state during growth and stress has never been carried out. Organellar redox state (E GSH) was measured using the fluorescent probes roGFP2 and pHluorin in Saccharomyces cerevisiae. In particular, we investigated changes in organellar redox state in response to various growth and stress conditions to better understand the relationship between redox-, oxidative- and environmental stress response systems. E GSH values of the cytosol, mitochondrial matrix and peroxisome were determined in exponential and stationary phase in various media. These values (-340 to -350 mV) were more reducing than previously reported. Interestingly, sub-cellular redox state remained unchanged when cells were challenged with stresses previously reported to affect redox homeostasis. Only hydrogen peroxide and heat stress significantly altered organellar redox state. Hydrogen peroxide stress altered the redox state of the glutathione disulfide/glutathione couple (GSSG, 2H(+)/2GSH) and pH. Recovery from moderate hydrogen peroxide stress was most rapid in the cytosol, followed by the mitochondrial matrix, with the peroxisome the least able to recover. Conversely, the bulk of the redox shift observed during heat stress resulted from alterations in pH and not the GSSG, 2H(+)/2GSH couple. This study presents the first direct measurement of pH-adjusted redox state in sub-cellular compartments during growth and stress conditions. Redox state is distinctly regulated in organelles and data presented challenge the notion that perturbation of redox state is central in the response to many stress conditions.

  19. Distinct redox regulation in sub-cellular compartments in response to various stress conditions in Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Anita Ayer

    Full Text Available Responses to many growth and stress conditions are assumed to act via changes to the cellular redox status. However, direct measurement of pH-adjusted redox state during growth and stress has never been carried out. Organellar redox state (E GSH was measured using the fluorescent probes roGFP2 and pHluorin in Saccharomyces cerevisiae. In particular, we investigated changes in organellar redox state in response to various growth and stress conditions to better understand the relationship between redox-, oxidative- and environmental stress response systems. E GSH values of the cytosol, mitochondrial matrix and peroxisome were determined in exponential and stationary phase in various media. These values (-340 to -350 mV were more reducing than previously reported. Interestingly, sub-cellular redox state remained unchanged when cells were challenged with stresses previously reported to affect redox homeostasis. Only hydrogen peroxide and heat stress significantly altered organellar redox state. Hydrogen peroxide stress altered the redox state of the glutathione disulfide/glutathione couple (GSSG, 2H(+/2GSH and pH. Recovery from moderate hydrogen peroxide stress was most rapid in the cytosol, followed by the mitochondrial matrix, with the peroxisome the least able to recover. Conversely, the bulk of the redox shift observed during heat stress resulted from alterations in pH and not the GSSG, 2H(+/2GSH couple. This study presents the first direct measurement of pH-adjusted redox state in sub-cellular compartments during growth and stress conditions. Redox state is distinctly regulated in organelles and data presented challenge the notion that perturbation of redox state is central in the response to many stress conditions.

  20. Compartment-Specific Biosensors Reveal a Complementary Subcellular Distribution of Bioactive Furin and PC7

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    Pierpaolo Ginefra

    2018-02-01

    Full Text Available Furin trafficking, and that of related proprotein convertases (PCs, may regulate which substrates are accessible for endoproteolysis, but tools to directly test this hypothesis have been lacking. Here, we develop targeted biosensors that indicate Furin activity in endosomes is 10-fold less inhibited by decanoyl-RVKR-chloromethylketone and enriched >3-fold in endosomes compared to the trans-Golgi network (TGN. Endogenous PC7, which resists this inhibitor, was active in distinct vesicles. Only overexpressed PC7 activity reached the cell surface, endosomes, and the TGN. A PLC motif in the cytosolic tail of PC7 was dispensable for endosomal activity, but it was specifically required for TGN recycling and to rescue proActivin-A cleavage in Furin-depleted B16F1 melanoma cells. In sharp contrast, PC7 complemented Furin in cleaving Notch1 independently of PLC-mediated TGN access. Our study provides a proof in principle that compartment-specific biosensors can be used to gain insight into the regulation of PC trafficking and to map the tropism of PC-specific inhibitors.

  1. Role of ER stress response in photodynamic therapy: ROS generated in different subcellular compartments trigger diverse cell death pathways.

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    Irena Moserova

    Full Text Available We have analyzed the molecular mechanisms of photoinduced cell death using porphyrins with similar structure differing only in the position of the ethylene glycol (EG chain on the phenyl ring. Meta- and para-positioned EG chains targeted porphyrins to different subcellular compartments. After photoactivation, both types of derivatives induced death of tumor cells via reactive oxygen species (ROS. Para derivatives pTPP(EG4 and pTPPF(EG4 primarily accumulated in lysosomes activated the p38 MAP kinase cascade, which in turn induced the mitochondrial apoptotic pathway. In contrast, meta porphyrin derivative mTPP(EG4 localized in the endoplasmic reticulum (ER induced dramatic changes in Ca(2+ homeostasis manifested by Ca(2+ rise in the cytoplasm, activation of calpains and stress caspase-12 or caspase-4. ER stress developed into unfolded protein response. Immediately after irradiation the PERK pathway was activated through phosphorylation of PERK, eIF2α and induction of transcription factors ATF4 and CHOP, which regulate stress response genes. PERK knockdown and PERK deficiency protected cells against mTPP(EG4-mediated apoptosis, confirming the causative role of the PERK pathway.

  2. Subcellular compartmentation of sugar signalling: Links among carbon cellular status, route of sucrolysis, sink-source allocation, and metabolic partitioning

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    Axel eTiessen

    2013-01-01

    Full Text Available Recent findings suggest that both subcellular compartmentation and route of sucrolysis are important for plant development, growth, and yield. Signalling effects are dependent on the tissue, cell type and stage of development. Downstream effects also depend on the amount and localisation of hexoses and disaccharides. All enzymes of sucrose metabolism (e.g. invertase, hexokinase, fructokinase, sucrose synthase, and sucrose 6-phosphate synthase are not produced from single genes, but from paralogue families in plant genomes. Each paralogue has unique expression across plant organs and developmental stages. Multiple isoforms can be targeted to different cellular compartments (e.g. plastids, mitochondria, nuclei, and cytosol. Many of the key enzymes are regulated by post-transcriptional modifications and associate in multimeric protein complexes. Some isoforms have regulatory functions, either in addition to or in replacement of their catalytic activity. This explains why some isozymes are not redundant, but also complicates elucidation of their specific involvement in sugar signalling. The subcellular compartmentation of sucrose metabolism forces refinement of some of the paradigms of sugar signalling during physiological processes. For example, the catalytic and signalling functions of diverse paralogues needs to be more carefully analysed in the context of post-genomic biology. It is important to note that it is the differential localization of both the sugars themselves as well as the sugar-metabolizing enzymes that ultimately led to sugar signalling. We conclude that a combination of subcellular complexity and gene duplication/subfunctionalization gave rise to sugar signalling as a regulatory mechanism in plant cells.

  3. Predicting the targeting of tail-anchored proteins to subcellular compartments in mammalian cells.

    Science.gov (United States)

    Costello, Joseph L; Castro, Inês G; Camões, Fátima; Schrader, Tina A; McNeall, Doug; Yang, Jing; Giannopoulou, Evdokia-Anastasia; Gomes, Sílvia; Pogenberg, Vivian; Bonekamp, Nina A; Ribeiro, Daniela; Wilmanns, Matthias; Jedd, Gregory; Islinger, Markus; Schrader, Michael

    2017-05-01

    Tail-anchored (TA) proteins contain a single transmembrane domain (TMD) at the C-terminus that anchors them to the membranes of organelles where they mediate critical cellular processes. Accordingly, mutations in genes encoding TA proteins have been identified in a number of severe inherited disorders. Despite the importance of correctly targeting a TA protein to its appropriate membrane, the mechanisms and signals involved are not fully understood. In this study, we identify additional peroxisomal TA proteins, discover more proteins that are present on multiple organelles, and reveal that a combination of TMD hydrophobicity and tail charge determines targeting to distinct organelle locations in mammals. Specifically, an increase in tail charge can override a hydrophobic TMD signal and re-direct a protein from the ER to peroxisomes or mitochondria and vice versa. We show that subtle changes in those parameters can shift TA proteins between organelles, explaining why peroxisomes and mitochondria have many of the same TA proteins. This enabled us to associate characteristic physicochemical parameters in TA proteins with particular organelle groups. Using this classification allowed successful prediction of the location of uncharacterized TA proteins for the first time. © 2017. Published by The Company of Biologists Ltd.

  4. COMPARTMENTS

    DEFF Research Database (Denmark)

    Binder, Janos X; Pletscher-Frankild, Sune; Tsafou, Kalliopi

    2014-01-01

    of the localization of a protein, it is thus necessary to consult multiple databases and prediction tools. To address this, we present the COMPARTMENTS resource, which integrates all sources listed above as well as the results of automatic text mining. The resource is automatically kept up to date with source...

  5. Optogenetic Tools for Subcellular Applications in Neuroscience.

    Science.gov (United States)

    Rost, Benjamin R; Schneider-Warme, Franziska; Schmitz, Dietmar; Hegemann, Peter

    2017-11-01

    The ability to study cellular physiology using photosensitive, genetically encoded molecules has profoundly transformed neuroscience. The modern optogenetic toolbox includes fluorescent sensors to visualize signaling events in living cells and optogenetic actuators enabling manipulation of numerous cellular activities. Most optogenetic tools are not targeted to specific subcellular compartments but are localized with limited discrimination throughout the cell. Therefore, optogenetic activation often does not reflect context-dependent effects of highly localized intracellular signaling events. Subcellular targeting is required to achieve more specific optogenetic readouts and photomanipulation. Here we first provide a detailed overview of the available optogenetic tools with a focus on optogenetic actuators. Second, we review established strategies for targeting these tools to specific subcellular compartments. Finally, we discuss useful tools and targeting strategies that are currently missing from the optogenetics repertoire and provide suggestions for novel subcellular optogenetic applications. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Fast subcellular localization by cascaded fusion of signal-based and homology-based methods

    Directory of Open Access Journals (Sweden)

    Wang Wei

    2011-10-01

    Full Text Available Abstract Background The functions of proteins are closely related to their subcellular locations. In the post-genomics era, the amount of gene and protein data grows exponentially, which necessitates the prediction of subcellular localization by computational means. Results This paper proposes mitigating the computation burden of alignment-based approaches to subcellular localization prediction by a cascaded fusion of cleavage site prediction and profile alignment. Specifically, the informative segments of protein sequences are identified by a cleavage site predictor using the information in their N-terminal shorting signals. Then, the sequences are truncated at the cleavage site positions, and the shortened sequences are passed to PSI-BLAST for computing their profiles. Subcellular localization are subsequently predicted by a profile-to-profile alignment support-vector-machine (SVM classifier. To further reduce the training and recognition time of the classifier, the SVM classifier is replaced by a new kernel method based on the perturbational discriminant analysis (PDA. Conclusions Experimental results on a new dataset based on Swiss-Prot Release 57.5 show that the method can make use of the best property of signal- and homology-based approaches and can attain an accuracy comparable to that achieved by using full-length sequences. Analysis of profile-alignment score matrices suggest that both profile creation time and profile alignment time can be reduced without significant reduction in subcellular localization accuracy. It was found that PDA enjoys a short training time as compared to the conventional SVM. We advocate that the method will be important for biologists to conduct large-scale protein annotation or for bioinformaticians to perform preliminary investigations on new algorithms that involve pairwise alignments.

  7. Targeting Tryptophan Decarboxylase to Selected Subcellular Compartments of Tobacco Plants Affects Enzyme Stability and in Vivo Function and Leads to a Lesion-Mimic Phenotype1

    Science.gov (United States)

    Di Fiore, Stefano; Li, Qiurong; Leech, Mark James; Schuster, Flora; Emans, Neil; Fischer, Rainer; Schillberg, Stefan

    2002-01-01

    Tryptophan decarboxylase (TDC) is a cytosolic enzyme that catalyzes an early step of the terpenoid indole alkaloid biosynthetic pathway by decarboxylation of l-tryptophan to produce the protoalkaloid tryptamine. In the present study, recombinant TDC was targeted to the chloroplast, cytosol, and endoplasmic reticulum (ER) of tobacco (Nicotiana tabacum) plants to evaluate the effects of subcellular compartmentation on the accumulation of functional enzyme and its corresponding enzymatic product. TDC accumulation and in vivo function was significantly affected by the subcellular localization. Immunoblot analysis demonstrated that chloroplast-targeted TDC had improved accumulation and/or stability when compared with the cytosolic enzyme. Because ER-targeted TDC was not detectable by immunoblot analysis and tryptamine levels found in transient expression studies and in transgenic plants were low, it was concluded that the recombinant TDC was most likely unstable if ER retained. Targeting TDC to the chloroplast stroma resulted in the highest accumulation level of tryptamine so far reported in the literature for studies on heterologous TDC expression in tobacco. However, plants accumulating high levels of functional TDC in the chloroplast developed a lesion-mimic phenotype that was probably triggered by the relatively high accumulation of tryptamine in this compartment. We demonstrate that subcellular targeting may provide a useful strategy for enhancing accumulation and/or stability of enzymes involved in secondary metabolism and to divert metabolic flux toward desired end products. However, metabolic engineering of plants is a very demanding task because unexpected, and possibly unwanted, effects may be observed on plant metabolism and/or phenotype. PMID:12114570

  8. Wingless signalling alters the levels, subcellular distribution and dynamics of Armadillo and E-cadherin in third instar larval wing imaginal discs.

    Directory of Open Access Journals (Sweden)

    Ildiko M L Somorjai

    2008-08-01

    Full Text Available Armadillo, the Drosophila orthologue of vertebrate ss-catenin, plays a dual role as the key effector of Wingless/Wnt1 signalling, and as a bridge between E-Cadherin and the actin cytoskeleton. In the absence of ligand, Armadillo is phosphorylated and targeted to the proteasome. Upon binding of Wg to its receptors, the "degradation complex" is inhibited; Armadillo is stabilised and enters the nucleus to transcribe targets.Although the relationship between signalling and adhesion has been extensively studied, few in vivo data exist concerning how the "transcriptional" and "adhesive" pools of Armadillo are regulated to orchestrate development. We have therefore addressed how the subcellular distribution of Armadillo and its association with E-Cadherin change in larval wing imaginal discs, under wild type conditions and upon signalling. Using confocal microscopy, we show that Armadillo and E-Cadherin are spatio-temporally regulated during development, and that a punctate species becomes concentrated in a subapical compartment in response to Wingless. In order to further dissect this phenomenon, we overexpressed Armadillo mutants exhibiting different levels of activity and stability, but retaining E-Cadherin binding. Arm(S10 displaces endogenous Armadillo from the AJ and the basolateral membrane, while leaving E-Cadherin relatively undisturbed. Surprisingly, DeltaNArm(1-155 caused displacement of both Armadillo and E-Cadherin, results supported by our novel method of quantification. However, only membrane-targeted Myr-DeltaNArm(1-155 produced comparable nuclear accumulation of Armadillo and signalling to Arm(S10. These experiments also highlighted a row of cells at the A/P boundary depleted of E-Cadherin at the AJ, but containing actin.Taken together, our results provide in vivo evidence for a complex non-linear relationship between Armadillo levels, subcellular distribution and Wingless signalling. Moreover, this study highlights the importance of

  9. Two isoforms of Saccharomyces cerevisiae glutaredoxin 2 are expressed in vivo and localize to different subcellular compartments.

    Science.gov (United States)

    Pedrajas, José R; Porras, Pablo; Martínez-Galisteo, Emilia; Padilla, C Alicia; Miranda-Vizuete, Antonio; Bárcena, J Antonio

    2002-06-15

    Glutaredoxin (Grx)2 from Saccharomyces cerevisiae is a member of the two-cysteine (dithiol) subfamily of Grxs involved in the defence against oxidative stress in yeast. Recombinant yeast Grx2p, expressed in Escherichia coli, behaves as a 'classical' Grx that efficiently catalyses the reduction of hydroxyethyl disulphide by GSH. Grx2p also catalyses the reduction of GSSG by dihydrolipoamide with even higher efficiency. Western blot analysis of S. cerevisiae crude extracts identifies two isoforms of Grx2p of 15.9 and 11.9 kDa respectively. The levels of these two isoforms reach a peak during the exponential phase of growth in normal yeast extract/peptone/dextrose ('YPD') medium, with the long form predominating over the short one. From immunochemical analysis of subcellular fractions, it is shown that both isoforms are present in mitochondria, but only the short one is detected in the cytosolic fraction. On the other hand, only the long form is prominent in microsomes. Mitochondrial isoforms should represent the processed and unprocessed products of an open reading frame (YDR513W), with a putative start codon 99 bp upstream of the GRX2 start codon described thus far. These results indicate that GRX2 contains two in-frame start codons, and that translation from the first AUG results in a product that is targeted to mitochondria. The cytosolic form would result either by initiation from the second AUG, or by differential processing of one single translation product.

  10. Intracellular pH (pHin) and cytosolic calcium ([Ca2+]cyt) regulation via ATPases: studies in cell populations, single cells, and subcellular compartments

    Science.gov (United States)

    Rojas, Jose D.; Sanka, Shankar C.; Gyorke, Sandor; Wesson, Donald E.; Minta, Akwasi; Martinez-Zaguilan, Raul

    1999-07-01

    Changes in pHin and (Ca2+)cyt are important in the signal transduction mechanisms leading to many physiological responses including cell growth, motility, secretion/exocytosis, etc. The concentrations of these ions are regulated via primary and secondary ion transporting mechanisms. In diabetes, specific pH and Ca2+ regulatory mechanism might be altered. To study these ions, we employ fluorescence spectroscopy, and cell imagin spectroscopy/confocal microscopy. pH and Ca2+ indicators are loaded in the cytosol with acetoxymethyl ester forms of dyes, and in endosomal/lysosomal (E/L) compartments by overnight incubation of cells with dextran- conjugated ion fluorescent probes. We focus on specific pH and Ca2+ regulatory systems: plasmalemmal vacuolar- type H+-ATPases (pm V-ATPases) and sarcoplasmic/endoplasmic reticulum Ca2+-ATPases (SERCA). As experimental models, we employ vascular smooth muscle (VSM) and microvascular endothelial cells. We have chosen these cells because they are important in blood flow regulation and in angiogenesis. These processes are altered in diabetes. In many cell types, ion transport processes are dependent on metabolism of glucose for maximal activity. Our main findings are: (a) glycolysis coupling the activity of SERCA is required for cytosolic Ca2+ homeostasis in both VSM and microvascular endothelial cells; (b) E/L compartments are important for pH and Ca2+ regulation via H+-ATPases and SERCA, respectively; and (c) pm-V- ATPases are important for pHin regulation in microvascular endothelial cells.

  11. Dynamic full field optical coherence tomography: subcellular metabolic contrast revealed in tissues by temporal analysis of interferometric signals

    CERN Document Server

    Apelian, Clement; Thouvenin, Olivier; Boccara, A Claude

    2016-01-01

    We developed a new endogenous approach to reveal subcellular metabolic contrast in fresh ex vivo tissues taking advantage of the time dependence of the full field optical coherence tomography interferometric signals. This method reveals signals linked with local activity of the endogenous scattering elements which can reveal cells where other imaging techniques fail or need exogenous contrast agents. We benefit from the micrometric transverse resolution of full field OCT to image intracellular features. We used this time dependence to identify different dynamics at the millisecond scale on a wide range of organs in normal or pathological conditions.

  12. [Effect of noise in submarine compartment on signal discrimination and arithmetic performance].

    Science.gov (United States)

    Hu, Z; Liang, Z; Shi, X; Tang, Z

    1997-06-01

    To study the effects of noise level in submarine compartment on signal discrimination and arithmetic performance, experiments were carried out on 13 subjects. The results showed that as noise level raised from moderate (73 dBA) to higher levels (85-92 dBA), work efficiency showed a progressive decrease, but when noise level reached 96 dBA the decrease in efficiency reached a steady state. The results indicated that impairment of efficiency apparently occurred at a level of 85 dBA and that the interference effect of noise was more pronounced on task performance with mental strain.

  13. Mutational analyses of the signals involved in the subcellular location of DSCR1

    Directory of Open Access Journals (Sweden)

    Henrique-Silva Flávio

    2002-09-01

    Full Text Available Abstract Background Down syndrome is the most frequent genetic disorder in humans. Rare cases involving partial trisomy of chromosome 21 allowed a small chromosomal region common to all carriers, called Down Syndrome Critical Region (DSCR, to be determined. The DSCR1 gene was identified in this region and is expressed preferentially in the brain, heart and skeletal muscle. Recent studies have shown that DSCR1 belongs to a family of proteins that binds and inhibits calcineurin, a serine-threonine phosphatase. The work reported on herein consisted of a study of the subcellular location of DSCR1 and DSCR1-mutated forms by fusion with a green fluorescent protein, using various cell lines, including human. Results The protein's location was preferentially nuclear, independently of the isoform, cell line and insertion in the GFP's N- or C-terminal. A segment in the C-terminal, which is important in the location of the protein, was identified by deletion. On the other hand, site-directed mutational analyses have indicated the involvement of some serine and threonine residues in this event. Conclusion In this paper, we discuss the identification of amino acids which can be important for subcellular location of DSCR1. The involvement of residues that are prone to phosphorylation suggests that the location and function of DSCR1 may be regulated by kinases and/or phosphatases.

  14. Differential subcellular targeting and activity-dependent subcellular localization of diacylglycerol kinase isozymes in transfected cells.

    Science.gov (United States)

    Kobayashi, Naoki; Hozumi, Yasukazu; Ito, Tsukasa; Hosoya, Takaaki; Kondo, Hisatake; Goto, Kaoru

    2007-08-01

    Diacylglycerol kinase (DGK) plays a pivotal role in cellular signal transduction through regulating levels of the second messenger diacylglycerol (DG). Previous studies have revealed that DGK is composed of a family of isozymes that show remarkable heterogeneity in terms of molecular structure, functional domains, tissue and cellular gene expression. Recently, it has been shown that DG is produced in various subcellular compartments including the plasma membrane, internal membranes, cytoskeleton, and nucleus. However, it remains unclear how DG is regulated at distinct subcellular sites. To address this point, we have used an epitope-tag expression system in cultured cells and investigated the subcellular localization of DGK isozymes under the same experimental conditions. We show here that DGK isozymes are targeted differentially to unique subcellular sites in transfected COS7 cells, including the cytoplasm, actin stress fibers, Golgi complex, endoplasmic reticulum, and nucleus. It is also shown that among the isozymes overexpression of DGKbeta causes fragmentation of actin stress fibers while a kinase-dead mutant of DGKbeta abolishes its colocalization with actin stress fibers. These data strongly suggest that each isozyme may be responsible for the metabolism of DG that is produced upon stimulation at a different and specific subcellular site and that DGKbeta activity might have effects on the reorganization of actin stress fibers in transfected COS7 cells.

  15. Defense Against Reactive Carbonyl Species Involves at Least Three Subcellular Compartments where Individual Components of the System Respond to Cellular Sugar Status.

    Science.gov (United States)

    Schmitz, Jessica; Dittmar, Isabell C; Brockmann, Jörn D; Schmidt, Marc; Hüdig, Meike; Rossoni, Alessandro W; Maurino, Veronica G

    2017-11-17

    Methylglyoxal (MGO) and glyoxal (GO) are toxic reactive carbonyl species generated as by-products of glycolysis. The pre-emption pathway for detoxification of these products, the glyoxalase (GLX) system, involves two consecutive reactions catalyzed by GLXI and GLXII. In Arabidopsis thaliana, the GLX system is encoded by three homologs of GLXI and three homologs of GLXII, from which several predicted GLXI and GLXII isoforms can be derived through alternative splicing. We identified the physiologically relevant splice forms using sequencing data and demonstrated that the resulting isoforms have different subcellular localizations. All three GLXI homologs are functional in vivo, as they complemented a yeast GLXI loss-of-function mutant. Efficient MGO and GO detoxification can be controlled by a switch in metal cofactor usage. MGO formation is closely connected to the flux through glycolysis and through the Calvin Benson cycle; accordingly, expression analysis indicated that GLXI is transcriptionally regulated by endogenous sugar levels. Analyses of Arabidopsis loss-of-function lines revealed that the elimination of toxic reactive carbonyl species during germination and seedling establishment depends on the activity of the cytosolic GLXI;3 isoform. The Arabidopsis GLX system involves the cytosol, chloroplasts, and mitochondria, which harbor individual components that might be utilized at specific developmental stages and respond differentially to cellular sugar status. © 2017 American Society of Plant Biologists. All rights reserved.

  16. Small Molecule DFPM Derivative-Activated Plant Resistance Protein Signaling in Roots Is Unaffected by EDS1 Subcellular Targeting Signal and Chemical Genetic Isolation of victr R-Protein Mutants.

    Science.gov (United States)

    Kunz, Hans-Henning; Park, Jiyoung; Mevers, Emily; García, Ana V; Highhouse, Samantha; Gerwick, William H; Parker, Jane E; Schroeder, Julian I

    2016-01-01

    The small molecule DFPM ([5-(3,4-dichlorophenyl)furan-2-yl]-piperidine-1-ylmethanethione) was recently shown to trigger signal transduction via early effector-triggered immunity signaling genes including EDS1 and PAD4 in Arabidopsis thaliana accession Col-0. Chemical genetic analyses of A. thaliana natural variants identified the plant Resistance protein-like Toll/Interleukin1 Receptor (TIR)-Nucleotide Binding (NB)-Leucine-Rich Repeat (LRR) protein VICTR as required for DFPM-mediated root growth arrest. Here a chemical genetic screen for mutants which disrupt DFPM-mediated root growth arrest in the Col-0 accession identified new mutant alleles of the TIR-NB-LRR gene VICTR. One allele, victr-6, carries a Gly216-to-Asp mutation in the Walker A domain supporting an important function of the VICTR nucleotide binding domain in DFPM responses consistent with VICTR acting as a canonical Resistance protein. The essential nucleo-cytoplasmic regulator of TIR-NB-LRR-mediated effector-triggered immunity, EDS1, was reported to have both nuclear and cytoplasmic actions in pathogen resistance. DFPM was used to investigate the requirements for subcellular EDS1 localization in DFPM-mediated root growth arrest. EDS1-YFP fusions engineered to localize mainly in the cytoplasm or the nucleus by tagging with a nuclear export signal (NES) or a nuclear localization signal (NLS), respectively, were tested. We found that wild-type EDS1-YFP and both the NES and NLS-tagged EDS1 variants were induced by DFPM treatments and fully complemented eds1 mutant plants in root responses to DFPM, suggesting that enrichment of EDS1 in either compartment could confer DFPM-mediated root growth arrest. We further found that a light and O2-dependent modification of DFPM is necessary to mediate DFPM signaling in roots. Chemical analyses including Liquid Chromatography-Mass Spectrometry and High-Resolution Atmospheric Pressure Chemical Ionization Mass Spectrometry identified a DFPM modification product that is

  17. PTEN and PI-3 kinase inhibitors control LPS signaling and the lymphoproliferative response in the CD19+ B cell compartment

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Alok R. [UCSD Department of Pediatrics, Moores UCSD Cancer Center, University of California School of Medicine, San Diego, CA 92093 (United States); Peirce, Susan K. [Department of Pediatrics, Emory University School of Medicine, Atlanta, GA (United States); Joshi, Shweta [UCSD Department of Pediatrics, Moores UCSD Cancer Center, University of California School of Medicine, San Diego, CA 92093 (United States); Durden, Donald L., E-mail: ddurden@ucsd.edu [UCSD Department of Pediatrics, Moores UCSD Cancer Center, University of California School of Medicine, San Diego, CA 92093 (United States); Division of Pediatric Hematology-Oncology, UCSD Rady Children' s Hospital, La Jolla, CA (United States)

    2014-09-10

    Pattern recognition receptors (PRRs), e.g. toll receptors (TLRs) that bind ligands within the microbiome have been implicated in the pathogenesis of cancer. LPS is a ligand for two TLR family members, TLR4 and RP105 which mediate LPS signaling in B cell proliferation and migration. Although LPS/TLR/RP105 signaling is well-studied; our understanding of the underlying molecular mechanisms controlling these PRR signaling pathways remains incomplete. Previous studies have demonstrated a role for PTEN/PI-3K signaling in B cell selection and survival, however a role for PTEN/PI-3K in TLR4/RP105/LPS signaling in the B cell compartment has not been reported. Herein, we crossed a CD19cre and PTEN{sup fl/fl} mouse to generate a conditional PTEN knockout mouse in the CD19+ B cell compartment. These mice were further crossed with an IL-14α transgenic mouse to study the combined effect of PTEN deletion, PI-3K inhibition and expression of IL-14α (a cytokine originally identified as a B cell growth factor) in CD19+ B cell lymphoproliferation and response to LPS stimulation. Targeted deletion of PTEN and directed expression of IL-14α in the CD19+ B cell compartment (IL-14+PTEN-/-) lead to marked splenomegaly and altered spleen morphology at baseline due to expansion of marginal zone B cells, a phenotype that was exaggerated by treatment with the B cell mitogen and TLR4/RP105 ligand, LPS. Moreover, LPS stimulation of CD19+ cells isolated from these mice display increased proliferation, augmented AKT and NFκB activation as well as increased expression of c-myc and cyclinD1. Interestingly, treatment of LPS treated IL-14+PTEN-/- mice with a pan PI-3K inhibitor, SF1126, reduced splenomegaly, cell proliferation, c-myc and cyclin D1 expression in the CD19+ B cell compartment and normalized the splenic histopathologic architecture. These findings provide the direct evidence that PTEN and PI-3K inhibitors control TLR4/RP105/LPS signaling in the CD19+ B cell compartment and that pan PI

  18. Modulatory compartments in cortex and local regulation of cholinergic tone.

    Science.gov (United States)

    Coppola, Jennifer J; Ward, Nicholas J; Jadi, Monika P; Disney, Anita A

    2016-09-01

    Neuromodulatory signaling is generally considered broad in its impact across cortex. However, variations in the characteristics of cortical circuits may introduce regionally-specific responses to diffuse modulatory signals. Features such as patterns of axonal innervation, tissue tortuosity and molecular diffusion, effectiveness of degradation pathways, subcellular receptor localization, and patterns of receptor expression can lead to local modification of modulatory inputs. We propose that modulatory compartments exist in cortex and can be defined by variation in structural features of local circuits. Further, we argue that these compartments are responsible for local regulation of neuromodulatory tone. For the cholinergic system, these modulatory compartments are regions of cortical tissue within which signaling conditions for acetylcholine are relatively uniform, but between which signaling can vary profoundly. In the visual system, evidence for the existence of compartments indicates that cholinergic modulation likely differs across the visual pathway. We argue that the existence of these compartments calls for thinking about cholinergic modulation in terms of finer-grained control of local cortical circuits than is implied by the traditional view of this system as a diffuse modulator. Further, an understanding of modulatory compartments provides an opportunity to better understand and perhaps correct signal modifications that lead to pathological states. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Differentiation of the lateral compartment of the cochlea requires a temporally restricted FGF20 signal.

    Directory of Open Access Journals (Sweden)

    Sung-Ho Huh

    2012-01-01

    Full Text Available A large proportion of age-related hearing loss is caused by loss or damage to outer hair cells in the organ of Corti. The organ of Corti is the mechanosensory transducing apparatus in the inner ear and is composed of inner hair cells, outer hair cells, and highly specialized supporting cells. The mechanisms that regulate differentiation of inner and outer hair cells are not known. Here we report that fibroblast growth factor 20 (FGF20 is required for differentiation of cells in the lateral cochlear compartment (outer hair and supporting cells within the organ of Corti during a specific developmental time. In the absence of FGF20, mice are deaf and lateral compartment cells remain undifferentiated, postmitotic, and unresponsive to Notch-dependent lateral inhibition. These studies identify developmentally distinct medial (inner hair and supporting cells and lateral compartments in the developing organ of Corti. The viability and hearing loss in Fgf20 knockout mice suggest that FGF20 may also be a deafness-associated gene in humans.

  20. Compartment specific importance of glutathione during abiotic and biotic stress

    Directory of Open Access Journals (Sweden)

    Bernd eZechmann

    2014-10-01

    Full Text Available The tripeptide thiol glutathione (γ-L-glutamyl-L-cysteinyl-glycine is the most important sulfur containing antioxidant in plants and essential for plant defense against abiotic and biotic stress conditions. It is involved in the detoxification of reactive oxygen species, redox signaling, the modulation of defense gene expression and important for the regulation of enzymatic activities. Even though changes in glutathione contents are well documented in plants and its roles in plant defense are well established, still too little is known about its compartment specific importance during abiotic and biotic stress conditions. Due to technical advances in the visualization of glutathione and the redox state of plants through microscopical methods some progress was made in the last few years in studying the importance of subcellular glutathione contents during stress conditions in plants. This review summarizes the data available on compartment specific importance of glutathione in the protection against abiotic and biotic stress conditions such as high light stress, exposure to cadmium, drought, and pathogen attack (Pseudomonas, Botrytis, Tobacco Mosaic Virus. The data will be discussed in connection with the subcellular accumulation of ROS during these conditions and glutathione synthesis which are both highly compartment specific (e.g. glutathione synthesis takes place in chloroplasts and the cytosol. Thus this review will reveal the compartment specific importance of glutathione during abiotic and biotic stress conditions.

  1. Subcellular targeting strategies for drug design and delivery.

    Science.gov (United States)

    Rajendran, Lawrence; Knölker, Hans-Joachim; Simons, Kai

    2010-01-01

    Many drug targets are localized to particular subcellular compartments, yet current drug design strategies are focused on bioavailability and tissue targeting and rarely address drug delivery to specific intracellular compartments. Insights into how the cell traffics its constituents to these different cellular locations could improve drug design. In this Review, we explore the fundamentals of membrane trafficking and subcellular organization, as well as strategies used by pathogens to appropriate these mechanisms and the implications for drug design and delivery.

  2. Assessment of microstructural signal compartments across the corpus callosum using multi-echo gradient recalled echo at 7 T.

    Science.gov (United States)

    Thapaliya, Kiran; Vegh, Viktor; Bollmann, Steffen; Barth, Markus

    2017-11-26

    Quantitative assessment of tissue microstructure is important in studying human brain diseases and disorders in which white matter is implicated, as it has been linked to demyelination, re-myelination, and axonal damage in clinical conditions. Ultra-high field magnetic resonance imaging data obtained using a multi-echo gradient echo sequence has been shown to contain information on myelin, axonal and extracellular compartments in white matter. In this study, we aimed to assess the sensitivity of a three-compartment model to estimate the variation of corresponding compartment parameters (water fraction, relaxation time and frequency shift) of the corpus callosum sub-regions, which are known to have different tissue structure. Additionally, we computed the g-ratio using myelin and axonal water fractions and performed a voxel-by-voxel analysis in the corpus callosum. Based on data acquired for ten participants, we show that the myelin compartment water fraction and T 2 ∗ is consistent across the corpus callosum sub-regions, whilst myelin frequency shift varies. The results show that the variation in water fraction, T 2 ∗ and frequency shift for the myelin signal compartment across the corpus callosum is smaller than for the axonal and extracellular signal compartments. The computed g-ratio was comparable to previously published studies in the corpus callosum. Our study suggests that a multi-echo GRE approach in vivo combined with a complex three-compartment model is sensitive to microstructural parameter variations across the human corpus callosum. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Palmitoylation of stathmin family proteins domain A controls Golgi versus mitochondrial subcellular targeting.

    Science.gov (United States)

    Chauvin, Stéphanie; Poulain, Fabienne E; Ozon, Sylvie; Sobel, André

    2008-10-01

    Precise localization of proteins to specialized subcellular domains is fundamental for proper neuronal development and function. The neural microtubule-regulatory phosphoproteins of the stathmin family are such proteins whose specific functions are controlled by subcellular localization. Whereas stathmin is cytosolic, SCG10, SCLIP and RB3/RB3'/RB3'' are localized to the Golgi and vesicle-like structures along neurites and at growth cones. We examined the molecular determinants involved in the regulation of this specific subcellular localization in hippocampal neurons in culture. We show that their conserved N-terminal domain A carrying two palmitoylation sites is dominant over the others for Golgi and vesicle-like localization. Using palmitoylation-deficient GFP (green fluorescent protein) fusion mutants, we demonstrate that domains A of stathmin proteins have the particular ability to control protein targeting to either Golgi or mitochondria, depending on their palmitoylation. This regulation involves the co-operation of two subdomains within domain A, and seems also to be under the control of its SLD (stathmin-like domain) extension. Our results unravel that, in specific biological conditions, palmitoylation of stathmin proteins might be able to control their targeting to express their functional activities at appropriate subcellular sites. They, more generally, open new perspectives regarding the role of palmitoylation as a signalling mechanism orienting proteins to their functional subcellular compartments.

  4. Chasing stress signals - Exposure to extracellular stimuli differentially affects the redox state of cell compartments in the wild type and signaling mutants of Botrytis cinerea.

    Science.gov (United States)

    Marschall, Robert; Schumacher, Julia; Siegmund, Ulrike; Tudzynski, Paul

    2016-05-01

    Reactive oxygen species (ROS) are important molecules influencing intracellular developmental processes as well as plant pathogen interactions. They are produced at the infection site and affect the intracellular redox homeostasis. However, knowledge of ROS signaling pathways, their connection to other signaling cascades, and tools for the visualization of intra- and extracellular ROS levels and their impact on the redox state are scarce. By using the genetically encoded biosensor roGFP2 we studied for the first time the differences between the redox states of the cytosol, the intermembrane space of mitochondria and the ER in the filamentous fungus Botrytis cinerea. We showed that the ratio of oxidized to reduced glutathione inside of the cellular compartments differ and that the addition of hydrogen peroxide (H2O2), calcium chloride (CaCl2) and the fluorescent dye calcofluor white (CFW) have a direct impact on the cellular redox states. Dependent on the type of stress agents applied, the redox states were affected in the different cellular compartments in a temporally shifted manner. By integrating the biosensor in deletion mutants of bcnoxA, bcnoxB, bctrx1 and bcltf1 we further elucidated the putative roles of the different proteins in distinct stress-response pathways. We showed that the redox states of ΔbcnoxA and ΔbcnoxB display a wild-type pattern upon exposure to H2O2, but appear to be strongly affected by CaCl2 and CFW. Moreover, we demonstrated the involvement of the light-responsive transcription factor BcLtf1 in the maintenance of the redox state in the intermembrane space of the mitochondria. Finally, we report that CaCl2 as well as cell wall stress-inducing agents stimulate ROS production and that ΔbcnoxB produces significantly less ROS than the wild type and ΔbcnoxA. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Subcellular Localization of a Plant Catalase-Phenol Oxidase, AcCATPO, from Amaranthus and Identification of a Non-canonical Peroxisome Targeting Signal.

    Science.gov (United States)

    Chen, Ning; Teng, Xiao-Lu; Xiao, Xing-Guo

    2017-01-01

    AcCATPO is a plant catalase-phenol oxidase recently identified from red amaranth. Its physiological function remains unexplored. As the starting step of functional analysis, here we report its subcellular localization and a non-canonical targeting signal. Commonly used bioinformatics programs predicted a peroxisomal localization for AcCATPO, but failed in identification of canonical peroxisomal targeting signals (PTS). The C-terminal GFP tagging led the fusion protein AcCATPO-GFP to the cytosol and the nucleus, but N-terminal tagging directed the GFP-AcCATPO to peroxisomes and nuclei, in transgenic tobacco. Deleting the tripeptide (PTM) at the extreme C-terminus almost ruled out the peroxisomal localization of GFP-AcCATPOΔ3, and removing the C-terminal decapeptide completely excluded peroxisomes as the residence of GFP-AcCATPOΔ10. Furthermore, this decapeptide as a targeting signal could import GFP-10aa to the peroxisome exclusively. Taken together, these results demonstrate that AcCATPO is localized to the peroxisome and the nucleus, and its peroxisomal localization is attributed to a non-canonical PTS1, the C-terminal decapeptide which contains an internal SRL motif and a conserved tripeptide P-S/T-I/M at the extreme of C-terminus. This work may further the study as to the physiological function of AcCATPO, especially clarify its involvement in betalain biosynthesis, and provide a clue to elucidate more non-canonic PTS.

  6. Subcellular Localization of a Plant Catalase-Phenol Oxidase, AcCATPO, from Amaranthus and Identification of a Non-canonical Peroxisome Targeting Signal

    Science.gov (United States)

    Chen, Ning; Teng, Xiao-Lu; Xiao, Xing-Guo

    2017-01-01

    AcCATPO is a plant catalase-phenol oxidase recently identified from red amaranth. Its physiological function remains unexplored. As the starting step of functional analysis, here we report its subcellular localization and a non-canonical targeting signal. Commonly used bioinformatics programs predicted a peroxisomal localization for AcCATPO, but failed in identification of canonical peroxisomal targeting signals (PTS). The C-terminal GFP tagging led the fusion protein AcCATPO-GFP to the cytosol and the nucleus, but N-terminal tagging directed the GFP-AcCATPO to peroxisomes and nuclei, in transgenic tobacco. Deleting the tripeptide (PTM) at the extreme C-terminus almost ruled out the peroxisomal localization of GFP-AcCATPOΔ3, and removing the C-terminal decapeptide completely excluded peroxisomes as the residence of GFP-AcCATPOΔ10. Furthermore, this decapeptide as a targeting signal could import GFP-10aa to the peroxisome exclusively. Taken together, these results demonstrate that AcCATPO is localized to the peroxisome and the nucleus, and its peroxisomal localization is attributed to a non-canonical PTS1, the C-terminal decapeptide which contains an internal SRL motif and a conserved tripeptide P-S/T-I/M at the extreme of C-terminus. This work may further the study as to the physiological function of AcCATPO, especially clarify its involvement in betalain biosynthesis, and provide a clue to elucidate more non-canonic PTS. PMID:28824680

  7. Subcellular Localization of a Plant Catalase-Phenol Oxidase, AcCATPO, from Amaranthus and Identification of a Non-canonical Peroxisome Targeting Signal

    Directory of Open Access Journals (Sweden)

    Ning Chen

    2017-08-01

    Full Text Available AcCATPO is a plant catalase-phenol oxidase recently identified from red amaranth. Its physiological function remains unexplored. As the starting step of functional analysis, here we report its subcellular localization and a non-canonical targeting signal. Commonly used bioinformatics programs predicted a peroxisomal localization for AcCATPO, but failed in identification of canonical peroxisomal targeting signals (PTS. The C-terminal GFP tagging led the fusion protein AcCATPO-GFP to the cytosol and the nucleus, but N-terminal tagging directed the GFP-AcCATPO to peroxisomes and nuclei, in transgenic tobacco. Deleting the tripeptide (PTM at the extreme C-terminus almost ruled out the peroxisomal localization of GFP-AcCATPOΔ3, and removing the C-terminal decapeptide completely excluded peroxisomes as the residence of GFP-AcCATPOΔ10. Furthermore, this decapeptide as a targeting signal could import GFP-10aa to the peroxisome exclusively. Taken together, these results demonstrate that AcCATPO is localized to the peroxisome and the nucleus, and its peroxisomal localization is attributed to a non-canonical PTS1, the C-terminal decapeptide which contains an internal SRL motif and a conserved tripeptide P-S/T-I/M at the extreme of C-terminus. This work may further the study as to the physiological function of AcCATPO, especially clarify its involvement in betalain biosynthesis, and provide a clue to elucidate more non-canonic PTS.

  8. Protein subcellular localization prediction using artificial intelligence technology.

    Science.gov (United States)

    Nair, Rajesh; Rost, Burkhard

    2008-01-01

    Proteins perform many important tasks in living organisms, such as catalysis of biochemical reactions, transport of nutrients, and recognition and transmission of signals. The plethora of aspects of the role of any particular protein is referred to as its "function." One aspect of protein function that has been the target of intensive research by computational biologists is its subcellular localization. Proteins must be localized in the same subcellular compartment to cooperate toward a common physiological function. Aberrant subcellular localization of proteins can result in several diseases, including kidney stones, cancer, and Alzheimer's disease. To date, sequence homology remains the most widely used method for inferring the function of a protein. However, the application of advanced artificial intelligence (AI)-based techniques in recent years has resulted in significant improvements in our ability to predict the subcellular localization of a protein. The prediction accuracy has risen steadily over the years, in large part due to the application of AI-based methods such as hidden Markov models (HMMs), neural networks (NNs), and support vector machines (SVMs), although the availability of larger experimental datasets has also played a role. Automatic methods that mine textual information from the biological literature and molecular biology databases have considerably sped up the process of annotation for proteins for which some information regarding function is available in the literature. State-of-the-art methods based on NNs and HMMs can predict the presence of N-terminal sorting signals extremely accurately. Ab initio methods that predict subcellular localization for any protein sequence using only the native amino acid sequence and features predicted from the native sequence have shown the most remarkable improvements. The prediction accuracy of these methods has increased by over 30% in the past decade. The accuracy of these methods is now on par with

  9. Characterization of the nuclear import and export signals, and subcellular transport mechanism of varicella-zoster virus ORF9.

    Science.gov (United States)

    Cai, Mingsheng; Wang, Shuai; Xing, Junji; Zheng, Chunfu

    2011-03-01

    Varicella-zoster virus (VZV) open reading frame 9 (ORF9) mRNA is one of the most abundantly expressed messages during VZV infection. However, little is known concerning the function of ORF9 protein. Here, we found that transient expression of ORF9 fused to enhanced yellow fluorescent protein (EYFP) in COS-7 cells showed a predominantly cytoplasmic localization in the absence of other viral proteins. By constructing a series of ORF9 variants fused to EYFP, a bona fide bipartite nuclear localization signal of ORF9 was, for the first time, determined and mapped to aa 16-32 (RRKTTPSYSGQYRTARR). Additionally, the nuclear export signal (NES) was identified and found to be in a leucine-rich region at aa 103-117 (LRHELVEDAVYENPL). Finally, ORF9 was demonstrated to be targeted to the cytoplasm through the functional NES by Ran and the chromosomal region maintenance 1-dependent pathway, and to the nucleus via an importin β-dependent pathway that does not require importin α5.

  10. Identification of novel plant peroxisomal targeting signals by a combination of machine learning methods and in vivo subcellular targeting analyses.

    Science.gov (United States)

    Lingner, Thomas; Kataya, Amr R; Antonicelli, Gerardo E; Benichou, Aline; Nilssen, Kjersti; Chen, Xiong-Yan; Siemsen, Tanja; Morgenstern, Burkhard; Meinicke, Peter; Reumann, Sigrun

    2011-04-01

    In the postgenomic era, accurate prediction tools are essential for identification of the proteomes of cell organelles. Prediction methods have been developed for peroxisome-targeted proteins in animals and fungi but are missing specifically for plants. For development of a predictor for plant proteins carrying peroxisome targeting signals type 1 (PTS1), we assembled more than 2500 homologous plant sequences, mainly from EST databases. We applied a discriminative machine learning approach to derive two different prediction methods, both of which showed high prediction accuracy and recognized specific targeting-enhancing patterns in the regions upstream of the PTS1 tripeptides. Upon application of these methods to the Arabidopsis thaliana genome, 392 gene models were predicted to be peroxisome targeted. These predictions were extensively tested in vivo, resulting in a high experimental verification rate of Arabidopsis proteins previously not known to be peroxisomal. The prediction methods were able to correctly infer novel PTS1 tripeptides, which even included novel residues. Twenty-three newly predicted PTS1 tripeptides were experimentally confirmed, and a high variability of the plant PTS1 motif was discovered. These prediction methods will be instrumental in identifying low-abundance and stress-inducible peroxisomal proteins and defining the entire peroxisomal proteome of Arabidopsis and agronomically important crop plants.

  11. Compartment syndromes

    Science.gov (United States)

    Mubarak, S. J.; Pedowitz, R. A.; Hargens, A. R.

    1989-01-01

    The compartment syndrome is defined as a condition in which high pressure within a closed fascial space (muscle compartment) reduces capillary blood perfusion below the level necessary for tissue viability'. This condition occurs in acute and chronic (exertional) forms, and may be secondary to a variety of causes. The end-result of an extended period of elevated intramuscular pressure may be the development of irreversible tissue injury and Volkmann's contracture. The goal of treatment of the compartment syndrome is the reduction of intracompartmental pressure thus facilitating reperfusion of ischaemic tissue and this goal may be achieved by decompressive fasciotomy. Controversy exists regarding the critical pressure-time thresholds for surgical decompression and the optimal diagnostic methods of measuring intracompartmental pressures. This paper will update and review some current knowledge regarding the pathophysiology, aetiology, diagnosis, and treatment of the acute compartment syndrome.

  12. Compartment syndromes

    Directory of Open Access Journals (Sweden)

    Aly Saber

    2014-01-01

    Full Text Available Body compartments bound by fascia and limited by bony backgrounds are found in the extremities, buttocks, abdomen and thoracic cavity; conditions that cause intracompartmental swelling and hypertension can lead to ischemia and limb loss. Although compartment syndromes are described in all body regions from head to toe, the etiology, diagnosis, treatment, and prevention are best characterized for three key body regions: the first is extremity, the second is abdominal, and the third is thoracic compartment syndromes. Thoracic compartment syndrome usually occurs as a result of pathological accumulation of air, fluid or blood in the mediastinum and has traditionally been described in trauma. As the intracranial contents are confined within a rigid bony cage, any increase in volume within this compartment as a result of brain oedema or an expanding traumatic intracranial haematoma, leads to a reciprocal decrease in the volume of cerebrospinal fluid and intracranial venous blood volume. Limb compartment syndromes may present either in acute or chronic clinical forms. Intra-abdominal pressure can be measured by direct or indirect methods. While the direct methods are quite accurate, they are impractical and not feasible for routine practice. Indirect measurement is done through inferior vena cava, gastric, rectal and urinary bladder. Indirect measurement through urinary bladder is the simplest and is considered the method of choice for intra-abdominal pressure measurement. The management of patients with intra-abdominal hypertension is based on four important principles: the first is related to the specific procedures aiming at lowering intra-abdominal pressure and the consequences of intra-abdominal hypertension and abdominal compartment syndrome; the second is for general support and medical management of the critically ill patient; while the third is surgical decompression and the fourth is optimization after surgical decompression.

  13. Malonyl-CoA decarboxylase (MCD) is differentially regulated in subcellular compartments by 5'AMP-activated protein kinase (AMPK). Studies using H9c2 cells overexpressing MCD and AMPK by adenoviral gene transfer technique.

    Science.gov (United States)

    Sambandam, Nandakumar; Steinmetz, Michael; Chu, Angel; Altarejos, Judith Y; Dyck, Jason R B; Lopaschuk, Gary D

    2004-07-01

    Malonyl-CoA, a potent inhibitor of carnitine pamitoyl transferase-I (CPT-I), plays a pivotal role in fuel selection in cardiac muscle. Malonyl-CoA decarboxylase (MCD) catalyzes the degradation of malonyl-CoA, removes a potent allosteric inhibition on CPT-I and thereby increases fatty acid oxidation in the heart. Although MCD has several Ser/Thr phosphorylation sites, whether it is regulated by AMP-activated protein kinase (AMPK) has been controversial. We therefore overexpressed MCD (Ad.MCD) and constitutively active AMPK (Ad.CA-AMPK) in H9c2 cells, using an adenoviral gene delivery approach in order to examine if MCD is regulated by AMPK. Cells infected with Ad.CA-AMPK demonstrated a fourfold increase in AMPK activity as compared with control cells expressing green fluorescent protein (Ad.GFP). MCD activity increased 40- to 50-fold in Ad.MCD + Ad.GFP cells when compared with Ad.GFP control. Co-expressing AMPK with MCD further augmented MCD expression and activity in Ad.MCD + Ad.CA-AMPK cells compared with the Ad.MCD + Ad.GFP control. Subcellular fractionation further revealed that 54.7 kDa isoform of MCD expression was significantly higher in cytosolic fractions of Ad.MCD + Ad.CA-AMPK cells than of the Ad.MCD +Ad.GFP control. However, the MCD activities in cytosolic fractions were not different between the two groups. Interestingly, in the mitochondrial fractions, MCD activity significantly increased in Ad.MCD + Ad.CA-AMPK cells when compared with Ad.MCD + Ad.GFP cells. Using phosphoserine and phosphothreonine antibodies, no phosphorylation of MCD by AMPK was observed. The increase in MCD activity in mitochondria-rich fractions of Ad.MCD + Ad.CA-AMPK cells was accompanied by an increase in the level of the 50.7 kDa isoform of MCD protein in the mitochondria. This differential regulation of MCD expression and activity in the mitochondria by AMPK may potentially regulate malonyl-CoA levels at sites nearby CPT-I on the mitochondria.

  14. Subcellular targeting and interactions among the Potato virus X TGB proteins.

    Science.gov (United States)

    Samuels, Timmy D; Ju, Ho-Jong; Ye, Chang-Ming; Motes, Christy M; Blancaflor, Elison B; Verchot-Lubicz, Jeanmarie

    2007-10-25

    Potato virus X (PVX) encodes three proteins named TGBp1, TGBp2, and TGBp3 which are required for virus cell-to-cell movement. To determine whether PVX TGB proteins interact during virus cell-cell movement, GFP was fused to each TGB coding sequence within the viral genome. Confocal microscopy was used to study subcellular accumulation of each protein in virus-infected plants and protoplasts. GFP:TGBp2 and TGBp3:GFP were both seen in the ER, ER-associated granular vesicles, and perinuclear X-bodies suggesting that these proteins interact in the same subdomains of the endomembrane network. When plasmids expressing CFP:TGBp2 and TGBp3:GFP were co-delivered to tobacco leaf epidermal cells, the fluorescent signals overlapped in ER-associated granular vesicles indicating that these proteins colocalize in this subcellular compartment. GFP:TGBp1 was seen in the nucleus, cytoplasm, rod-like inclusion bodies, and in punctate sites embedded in the cell wall. The puncta were reminiscent of previous reports showing viral proteins in plasmodesmata. Experiments using CFP:TGBp1 and YFP:TGBp2 or TGBp3:GFP showed CFP:TGBp1 remained in the cytoplasm surrounding the endomembrane network. There was no evidence that the granular vesicles contained TGBp1. Yeast two hybrid experiments showed TGBp1 self associates but failed to detect interactions between TGBp1 and TGBp2 or TGBp3. These experiments indicate that the PVX TGB proteins have complex subcellular accumulation patterns and likely cooperate across subcellular compartments to promote virus infection.

  15. Distinct cellular and subcellular distributions of G protein-coupled receptor kinase and arrestin isoforms in the striatum.

    Directory of Open Access Journals (Sweden)

    Evgeny Bychkov

    Full Text Available G protein-coupled receptor kinases (GRKs and arrestins mediate desensitization of G protein-coupled receptors (GPCR. Arrestins also mediate G protein-independent signaling via GPCRs. Since GRK and arrestins demonstrate no strict receptor specificity, their functions in the brain may depend on their cellular complement, expression level, and subcellular targeting. However, cellular expression and subcellular distribution of GRKs and arrestins in the brain is largely unknown. We show that GRK isoforms GRK2 and GRK5 are similarly expressed in direct and indirect pathway neurons in the rat striatum. Arrestin-2 and arrestin-3 are also expressed in neurons of both pathways. Cholinergic interneurons are enriched in GRK2, arrestin-3, and GRK5. Parvalbumin-positive interneurons express more of GRK2 and less of arrestin-2 than medium spiny neurons. The GRK5 subcellular distribution in the human striatal neurons is altered by its phosphorylation: unphosphorylated enzyme preferentially localizes to synaptic membranes, whereas phosphorylated GRK5 is found in plasma membrane and cytosolic fractions. Both GRK isoforms are abundant in the nucleus of human striatal neurons, whereas the proportion of both arrestins in the nucleus was equally low. However, overall higher expression of arrestin-2 yields high enough concentration in the nucleus to mediate nuclear functions. These data suggest cell type- and subcellular compartment-dependent differences in GRK/arrestin-mediated desensitization and signaling.

  16. Subcellular compartmentation of glutathione in dicotyledonous plants

    Science.gov (United States)

    Müller, Maria

    2010-01-01

    This study describes the subcellular distribution of glutathione in roots and leaves of different plant species (Arabidopsis, Cucurbita, and Nicotiana). Glutathione is an important antioxidant and redox buffer which is involved in many metabolic processes including plant defense. Thus information on the subcellular distribution in these model plants especially during stress situations provides a deeper insight into compartment specific defense reactions and reflects the occurrence of compartment specific oxidative stress. With immunogold cytochemistry and computer-supported transmission electron microscopy glutathione could be localized in highest contents in mitochondria, followed by nuclei, peroxisomes, the cytosol, and plastids. Within chloroplasts and mitochondria, glutathione was restricted to the stroma and matrix, respectively, and did not occur in the lumen of cristae and thylakoids. Glutathione was also found at the membrane and in the lumen of the endoplasmic reticulum. It was also associated with the trans and cis side of dictyosomes. None or only very little glutathione was detected in vacuoles and the apoplast of mesophyll and root cells. Additionally, glutathione was found in all cell compartments of phloem vessels, vascular parenchyma cells (including vacuoles) but was absent in xylem vessels. The specificity of this method was supported by the reduction of glutathione labeling in all cell compartments (up to 98%) of the glutathione-deficient Arabidopsis thaliana rml1 mutant. Additionally, we found a similar distribution of glutathione in samples after conventional fixation and rapid microwave-supported fixation. Thus, indicating that a redistribution of glutathione does not occur during sample preparation. Summing up, this study gives a detailed insight into the subcellular distribution of glutathione in plants and presents solid evidence for the accuracy and specificity of the applied method. PMID:20186447

  17. Method and apparatus to assess compartment syndrome

    Science.gov (United States)

    Ueno, Toshiaki (Inventor); Hargens, Alan R. (Inventor); Yost, William T. (Inventor)

    2008-01-01

    A method and apparatus for measuring pressure buildup in a body compartment that encases muscular tissue. The method includes assessing the body compartment configuration and identifying the effect of pulsatile components on at least one compartment dimension. This process is used in preventing tissue necrosis, and in decisions of whether to perform surgery on the body compartment for prevention of Compartment Syndrome. An apparatus is used for measuring excess pressure in the body compartment having components for imparting ultrasonic waves such as a transducer, placing the transducer to impart the ultrasonic waves, capturing the reflected imparted ultrasonic waves, and converting them to electrical signals, a pulsed phase-locked loop device for assessing a body compartment configuration and producing an output signal, and means for mathematically manipulating the output signal to thereby categorize pressure build-up in the body compartment from the mathematical manipulations.

  18. Measurement of endogenous subcellular concentration of steroids in tissue

    NARCIS (Netherlands)

    Poortman, J.; Landeghem, A.A.J. van; Helmond-Agema, A.; Thussen, J.H.H.

    1984-01-01

    A reliable method for the extraction of steroid hormones from human uterine tissue and the subsequent measurement of these hormones in the subcellular compartments by radioimmunoassay is described. Extraction of radioactive steroid hormones from in vivo labelled human uterine tissue by different

  19. Correlation profiling of brain sub-cellular proteomes reveals co-assembly of synaptic proteins and subcellular distribution

    NARCIS (Netherlands)

    Pandya, N.J. (Nikhil J.); Koopmans, F. (Frank); J.A. Slotman (Johan A.); Paliukhovich, I. (Iryna); A.B. Houtsmuller (Adriaan); A.B. Smit (August); Li, K.W. (Ka Wan)

    2017-01-01

    textabstractProtein correlation profiling might assist in defining co-assembled proteins and subcellular distribution. Here, we quantified the proteomes of five biochemically isolated mouse brain cellular sub-fractions, with emphasis on synaptic compartments, from three brain regions, hippocampus,

  20. Proteome-wide Subcellular Topologies of E. coli Polypeptides Database (STEPdb)*

    Science.gov (United States)

    Orfanoudaki, Georgia; Economou, Anastassios

    2014-01-01

    Cell compartmentalization serves both the isolation and the specialization of cell functions. After synthesis in the cytoplasm, over a third of all proteins are targeted to other subcellular compartments. Knowing how proteins are distributed within the cell and how they interact is a prerequisite for understanding it as a whole. Surface and secreted proteins are important pathogenicity determinants. Here we present the STEP database (STEPdb) that contains a comprehensive characterization of subcellular localization and topology of the complete proteome of Escherichia coli. Two widely used E. coli proteomes (K-12 and BL21) are presented organized into thirteen subcellular classes. STEPdb exploits the wealth of genetic, proteomic, biochemical, and functional information on protein localization, secretion, and targeting in E. coli, one of the best understood model organisms. Subcellular annotations were derived from a combination of bioinformatics prediction, proteomic, biochemical, functional, topological data and extensive literature re-examination that were refined through manual curation. Strong experimental support for the location of 1553 out of 4303 proteins was based on 426 articles and some experimental indications for another 526. Annotations were provided for another 320 proteins based on firm bioinformatic predictions. STEPdb is the first database that contains an extensive set of peripheral IM proteins (PIM proteins) and includes their graphical visualization into complexes, cellular functions, and interactions. It also summarizes all currently known protein export machineries of E. coli K-12 and pairs them, where available, with the secretory proteins that use them. It catalogs the Sec- and TAT-utilizing secretomes and summarizes their topological features such as signal peptides and transmembrane regions, transmembrane topologies and orientations. It also catalogs physicochemical and structural features that influence topology such as abundance

  1. Membrane Signaling Induced by High Doses of Ionizing Radiation in the Endothelial Compartment. Relevance in Radiation Toxicity

    Directory of Open Access Journals (Sweden)

    Isabelle Corre

    2013-11-01

    Full Text Available Tumor areas can now be very precisely delimited thanks to technical progress in imaging and ballistics. This has also led to the development of novel radiotherapy protocols, delivering higher doses of ionizing radiation directly to cancer cells. Despite this, radiation toxicity in healthy tissue remains a major issue, particularly with dose-escalation in these new protocols. Acute and late tissue damage following irradiation have both been linked to the endothelium irrigating normal tissues. The molecular mechanisms involved in the endothelial response to high doses of radiation are associated with signaling from the plasma membrane, mainly via the acid sphingomyelinase/ceramide pathway. This review describes this signaling pathway and discusses the relevance of targeting endothelial signaling to protect healthy tissues from the deleterious effects of high doses of radiation.

  2. TLR2 ligands induce NF-κB activation from endosomal compartments of human monocytes.

    Directory of Open Access Journals (Sweden)

    Karim J Brandt

    Full Text Available Localization of Toll-like receptors (TLR in subcellular organelles is a major strategy to regulate innate immune responses. While TLR4, a cell-surface receptor, signals from both the plasma membrane and endosomal compartments, less is known about the functional role of endosomal trafficking upon TLR2 signaling. Here we show that the bacterial TLR2 ligands Pam3CSK4 and LTA activate NF-κB-dependent signaling from endosomal compartments in human monocytes and in a NF-κB sensitive reporter cell line, despite the expression of TLR2 at the cell surface. Further analyses indicate that TLR2-induced NF-κB activation is controlled by a clathrin/dynamin-dependent endocytosis mechanism, in which CD14 serves as an important upstream regulator. These findings establish that internalization of cell-surface TLR2 into endosomal compartments is required for NF-κB activation. These observations further demonstrate the need of endocytosis in the activation and regulation of TLR2-dependent signaling pathways.

  3. Meredys, a multi-compartment reaction-diffusion simulator using multistate realistic molecular complexes

    Directory of Open Access Journals (Sweden)

    Le Novère Nicolas

    2010-03-01

    Full Text Available Abstract Background Most cellular signal transduction mechanisms depend on a few molecular partners whose roles depend on their position and movement in relation to the input signal. This movement can follow various rules and take place in different compartments. Additionally, the molecules can form transient complexes. Complexation and signal transduction depend on the specific states partners and complexes adopt. Several spatial simulator have been developed to date, but none are able to model reaction-diffusion of realistic multi-state transient complexes. Results Meredys allows for the simulation of multi-component, multi-feature state molecular species in two and three dimensions. Several compartments can be defined with different diffusion and boundary properties. The software employs a Brownian dynamics engine to simulate reaction-diffusion systems at the reactive particle level, based on compartment properties, complex structure, and hydro-dynamic radii. Zeroth-, first-, and second order reactions are supported. The molecular complexes have realistic geometries. Reactive species can contain user-defined feature states which can modify reaction rates and outcome. Models are defined in a versatile NeuroML input file. The simulation volume can be split in subvolumes to speed up run-time. Conclusions Meredys provides a powerful and versatile way to run accurate simulations of molecular and sub-cellular systems, that complement existing multi-agent simulation systems. Meredys is a Free Software and the source code is available at http://meredys.sourceforge.net/.

  4. Protein subcellular localization assays using split fluorescent proteins

    Science.gov (United States)

    Waldo, Geoffrey S [Santa Fe, NM; Cabantous, Stephanie [Los Alamos, NM

    2009-09-08

    The invention provides protein subcellular localization assays using split fluorescent protein systems. The assays are conducted in living cells, do not require fixation and washing steps inherent in existing immunostaining and related techniques, and permit rapid, non-invasive, direct visualization of protein localization in living cells. The split fluorescent protein systems used in the practice of the invention generally comprise two or more self-complementing fragments of a fluorescent protein, such as GFP, wherein one or more of the fragments correspond to one or more beta-strand microdomains and are used to "tag" proteins of interest, and a complementary "assay" fragment of the fluorescent protein. Either or both of the fragments may be functionalized with a subcellular targeting sequence enabling it to be expressed in or directed to a particular subcellular compartment (i.e., the nucleus).

  5. Subcellular Distribution of Glutathione Precursors in Arabidopsis thaliana

    Science.gov (United States)

    Koffler, Barbara Eva; Maier, Romana; Zechmann, Bernd

    2011-01-01

    Abstract Glutathione is an important antioxidant and has many important functions in plant development, growth and defense. Glutathione synthesis and degradation is highly compartment-specific and relies on the subcellular availability of its precursors, cysteine, glutamate, glycine and γ-glutamylcysteine especially in plastids and the cytosol which are considered as the main centers for glutathione synthesis. The availability of glutathione precursors within these cell compartments is therefore of great importance for successful plant development and defense. The aim of this study was to investigate the compartment-specific importance of glutathione precursors in Arabidopsis thaliana. The subcellular distribution was compared between wild type plants (Col-0), plants with impaired glutathione synthesis (glutathione deficient pad2-1 mutant, wild type plants treated with buthionine sulfoximine), and one complemented line (OE3) with restored glutathione synthesis. Immunocytohistochemistry revealed that the inhibition of glutathione synthesis induced the accumulation of the glutathione precursors cysteine, glutamate and glycine in most cell compartments including plastids and the cytosol. A strong decrease could be observed in γ-glutamylcysteine (γ-EC) contents in these cell compartments. These experiments demonstrated that the inhibition of γ-glutamylcysteine synthetase (GSH1) – the first enzyme of glutathione synthesis – causes a reduction of γ-EC levels and an accumulation of all other glutathione precursors within the cells. PMID:22050910

  6. Triple subcellular targeting of isopentenyl diphosphate isomerases encoded by a single gene.

    Science.gov (United States)

    Guirimand, Grégory; Guihur, Anthony; Phillips, Michael A; Oudin, Audrey; Glévarec, Gaëlle; Mahroug, Samira; Melin, Céline; Papon, Nicolas; Clastre, Marc; Giglioli-Guivarc'h, Nathalie; St-Pierre, Benoit; Rodríguez-Concepción, Manuel; Burlat, Vincent; Courdavault, Vincent

    2012-11-01

    Isopentenyl diphosphate isomerase (IDI) is a key enzyme of the isoprenoid pathway, catalyzing the interconversion of isopentenyl diphosphate and dimethylallyl diphosphate, the universal precursors of all isoprenoids. In plants, several subcellular compartments, including cytosol/ER, peroxisomes, mitochondria and plastids, are involved in isoprenoid biosynthesis. Here, we report on the unique triple targeting of two Catharanthus roseus IDI isoforms encoded by a single gene (CrIDI1). The triple localization of CrIDI1 in mitochondria, plastids and peroxisomes is explained by alternative transcription initiation of CrIDI1, by the specificity of a bifunctional N-terminal mitochondria/plastid transit peptide and by the presence of a C-terminal peroxisomal targeting signal. Moreover, bimolecular fluorescence complementation assays revealed self-interactions suggesting that the IDI likely acts as a multimer in vivo.

  7. Measurement of endogenous subcellular concentration of steroids in tissue

    OpenAIRE

    Poortman, J.; Landeghem, A.A.J. van; Helmond-Agema, A.; Thussen, J.H.H.

    1984-01-01

    A reliable method for the extraction of steroid hormones from human uterine tissue and the subsequent measurement of these hormones in the subcellular compartments by radioimmunoassay is described. Extraction of radioactive steroid hormones from in vivo labelled human uterine tissue by different methods reveals that an almost quantitative extraction of steroid hormones from the nuclear fraction is obtained by sonication in ethanol-acetone. Extraction of steroid hormones with diethylether from...

  8. Reconstituting Corticostriatal Network on-a-Chip Reveals the Contribution of the Presynaptic Compartment to Huntington's Disease.

    Science.gov (United States)

    Virlogeux, Amandine; Moutaux, Eve; Christaller, Wilhelm; Genoux, Aurélie; Bruyère, Julie; Fino, Elodie; Charlot, Benoit; Cazorla, Maxime; Saudou, Frédéric

    2018-01-02

    Huntington's disease (HD), a devastating neurodegenerative disorder, strongly affects the corticostriatal network, but the contribution of pre- and postsynaptic neurons in the first phases of disease is unclear due to difficulties performing early subcellular investigations in vivo. Here, we have developed an on-a-chip approach to reconstitute an HD corticostriatal network in vitro, using microfluidic devices compatible with subcellular resolution. We observed major defects in the different compartments of the corticostriatal circuit, from presynaptic dynamics to synaptic structure and transmission and to postsynaptic traffic and signaling, that correlate with altered global synchrony of the network. Importantly, the genetic status of the presynaptic compartment was necessary and sufficient to alter or restore the circuit. This highlights an important weight for the presynaptic compartment in HD that has to be considered for future therapies. This disease-on-a-chip microfluidic platform is thus a physiologically relevant in vitro system for investigating pathogenic mechanisms and for identifying drugs. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  9. ABA Regulates Subcellular Redistribution of OsABI-LIKE2, a Negative Regulator in ABA Signaling, to Control Root Architecture and Drought Resistance in Oryza sativa.

    Science.gov (United States)

    Li, Chengxiang; Shen, Hongyun; Wang, Tao; Wang, Xuelu

    2015-12-01

    The phytohormone ABA is a key stress signal in plants. Although the identification of ABA receptors led to significant progress in understanding the Arabidopsis ABA signaling pathway, there are still many unsolved mysteries regarding ABA signaling in monocots, such as rice. Here, we report that a rice ortholog of AtABI1 and AtABI2, named OsABI-LIKE2 (OsABIL2), plays a negative role in rice ABA signaling. Overexpression of OsABIL2 not only led to ABA insensitivity, but also significantly altered plant developmental phenotypes, including stomatal density and root architecture, which probably caused the hypersensitivity to drought stress. OsABIL2 interacts with OsPYL1, SAPK8 and SAPK10 both in vitro and in vivo, and the phosphatase activity of OsABIL2 was repressed by ABA-bound OsPYL1. However, unlike many other solely nuclear-localized clade A type 2C protein phosphatases (PP2Cs), OsABIL2 is localized in both the nucleus and cytosol. Furthermore, OsABIL2 interacts with and co-localized with OsPYL1 mainly in the cytosol, and ABA treatment regulates the nucleus-cytosol distribution of OsABIL2, suggesting a different mechanism for the activation of ABA signaling. Taken together, this study provides significant insights into rice ABA signaling and indicates the important role of OsABIL2 in regulating root development. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  10. Subcellular targeting and dynamic regulation of PTEN: Implications for neuronal cells and neurological disorders

    Directory of Open Access Journals (Sweden)

    Patricia eKreis

    2014-04-01

    Full Text Available PTEN is a lipid and protein phosphatase that regulates a diverse range of cellular mechanisms. PTEN is mainly present in the cytosol and transiently associates with the plasma membrane to dephosphorylate PI(3,4,5P3, thereby antagonizing the PI3-Kinase signaling pathway. Recently, PTEN has been shown to associate also with organelles such as the endoplasmic reticulum, the mitochondria or the nucleus, and to be secreted outside of the cell. In addition, PTEN dynamically localizes to specialized sub-cellular compartments such as the neuronal growth cone or dendritic spines. The diverse localizations of PTEN imply a tight temporal and spatial regulation, orchestrated by mechanisms such as posttranslational modifications, formation of distinct protein-protein interactions or the activation/recruitment of PTEN downstream of external cues. The regulation of PTEN function is thus not only important at the enzymatic activity level, but is also associated to its spatial distribution. In this review we will summarize (i recent findings that highlight mechanisms controlling PTEN movement and sub-cellular localization, and (ii current understanding of how PTEN localization is achieved by mechanisms controlling posttranslational modification, by association with binding partners and by PTEN structural or activity requirements. Finally, we will discuss the possible roles of compartmentalized PTEN in developing and mature neurons in health and disease.

  11. Subcellular targeting and dynamic regulation of PTEN: implications for neuronal cells and neurological disorders.

    Science.gov (United States)

    Kreis, Patricia; Leondaritis, George; Lieberam, Ivo; Eickholt, Britta J

    2014-01-01

    PTEN is a lipid and protein phosphatase that regulates a diverse range of cellular mechanisms. PTEN is mainly present in the cytosol and transiently associates with the plasma membrane to dephosphorylate PI(3,4,5)P3, thereby antagonizing the PI3-Kinase signaling pathway. Recently, PTEN has been shown to associate also with organelles such as the endoplasmic reticulum (ER), the mitochondria, or the nucleus, and to be secreted outside of the cell. In addition, PTEN dynamically localizes to specialized sub-cellular compartments such as the neuronal growth cone or dendritic spines. The diverse localizations of PTEN imply a tight temporal and spatial regulation, orchestrated by mechanisms such as posttranslational modifications, formation of distinct protein-protein interactions, or the activation/recruitment of PTEN downstream of external cues. The regulation of PTEN function is thus not only important at the enzymatic activity level, but is also associated to its spatial distribution. In this review we will summarize (i) recent findings that highlight mechanisms controlling PTEN movement and sub-cellular localization, and (ii) current understanding of how PTEN localization is achieved by mechanisms controlling posttranslational modification, by association with binding partners and by PTEN structural or activity requirements. Finally, we will discuss the possible roles of compartmentalized PTEN in developing and mature neurons in health and disease.

  12. Drosophila Zpr1 (Zinc finger protein 1 is required downstream of both EGFR and FGFR signaling in tracheal subcellular lumen formation.

    Directory of Open Access Journals (Sweden)

    Oscar E Ruiz

    Full Text Available The cellular and molecular cues involved in creating branched tubular networks that transport liquids or gases throughout an organism are not well understood. To identify factors required in branching and lumen formation of Drosophila tracheal terminal cells, a model for branched tubular networks, we performed a forward genetic-mosaic screen to isolate mutations affecting these processes. From this screen, we have identified the first Drosophila mutation in the gene Zpr1 (Zinc finger protein 1 by the inability of Zpr1-mutant terminal cells to form functional, gas-filled lumens. We show that Zpr1 defective cells initiate lumen formation, but are blocked from completing the maturation required for gas filling. Zpr1 is an evolutionarily conserved protein first identified in mammalian cells as a factor that binds the intracellular domain of the unactivated epidermal growth factor receptor (EGFR. We show that down-regulation of EGFR in terminal cells phenocopies Zpr1 mutations and that Zpr1 is epistatic to ectopic lumen formation driven by EGFR overexpression. However, while Zpr1 mutants are fully penetrant, defects observed when reducing EGFR activity are only partially penetrant. These results suggest that a distinct pathway operating in parallel to the EGFR pathway contributes to lumen formation, and this pathway is also dependent on Zpr1. We provide evidence that this alternative pathway may involve fibroblast growth factor receptor (FGFR signaling. We suggest a model in which Zpr1 mediates both EGFR and FGFR signal transduction cascades required for lumen formation in terminal cells. To our knowledge, this is the first genetic evidence placing Zpr1 downstream of EGFR signaling, and the first time Zpr1 has been implicated in FGFR signaling. Finally, we show that down-regulation of Smn, a protein known to interact with Zpr1 in mammalian cells, shows defects similar to Zpr1 mutants.

  13. Probing of the nuclear import and export signals and subcellular transport mechanism of varicella-zoster virus tegument protein open reading frame 10.

    Science.gov (United States)

    Cai, Mingsheng; Wang, Shuai; Long, Jing; Zheng, Chunfu

    2012-02-01

    Varicella-zoster virus open reading frame 10 (ORF10), a tegument protein present in the virion, is a member of the alphaherpesvirus UL48 gene family that shares considerable amino acid sequence homology with the UL48 prototype, herpes simplex virus type 1 VP16. VP16 serves multiple functions, including transcriptional activation of viral immediate-early genes. Furthermore, VP16 has been shown to be involved in some aspects of virus assembly and/or maturation. However, little is known concerning the function of ORF10. Here, we found that transient expression of ORF10 fused to enhanced yellow fluorescent protein (EYFP) in COS-7 cells showed the predominantly nuclear localization in the absence of other viral proteins. By constructing a series of ORF10 variants fused to EYFP, a bona fide bipartite nuclear localization signal of ORF10 was, for the first time, determined and mapped to amino acids (aa) 302-347. Additionally, the nuclear export signal (NES) was identified and found to be in a leucine-rich region at aa 226-236. Finally, ORF10 was demonstrated to be targeted to the cytoplasm through the functional NES by chromosomal region maintenance 1-dependent pathway, and to the nucleus via Ran and importin β1-dependent pathway that does not require importin α5.

  14. Identification of Novel Plant Peroxisomal Targeting Signals by a Combination of Machine Learning Methods and in Vivo Subcellular Targeting Analyses[W

    Science.gov (United States)

    Lingner, Thomas; Kataya, Amr R.; Antonicelli, Gerardo E.; Benichou, Aline; Nilssen, Kjersti; Chen, Xiong-Yan; Siemsen, Tanja; Morgenstern, Burkhard; Meinicke, Peter; Reumann, Sigrun

    2011-01-01

    In the postgenomic era, accurate prediction tools are essential for identification of the proteomes of cell organelles. Prediction methods have been developed for peroxisome-targeted proteins in animals and fungi but are missing specifically for plants. For development of a predictor for plant proteins carrying peroxisome targeting signals type 1 (PTS1), we assembled more than 2500 homologous plant sequences, mainly from EST databases. We applied a discriminative machine learning approach to derive two different prediction methods, both of which showed high prediction accuracy and recognized specific targeting-enhancing patterns in the regions upstream of the PTS1 tripeptides. Upon application of these methods to the Arabidopsis thaliana genome, 392 gene models were predicted to be peroxisome targeted. These predictions were extensively tested in vivo, resulting in a high experimental verification rate of Arabidopsis proteins previously not known to be peroxisomal. The prediction methods were able to correctly infer novel PTS1 tripeptides, which even included novel residues. Twenty-three newly predicted PTS1 tripeptides were experimentally confirmed, and a high variability of the plant PTS1 motif was discovered. These prediction methods will be instrumental in identifying low-abundance and stress-inducible peroxisomal proteins and defining the entire peroxisomal proteome of Arabidopsis and agronomically important crop plants. PMID:21487095

  15. The Subcellular Localization of Tubby-Like Proteins and Participation in Stress Signaling and Root Colonization by the Mutualist Piriformospora indica1[W

    Science.gov (United States)

    Reitz, Marco Uwe; Bissue, Jeff Kweku; Zocher, Kathleen; Attard, Agnès; Hückelhoven, Ralph; Becker, Katja; Imani, Jafargholi; Eichmann, Ruth; Schäfer, Patrick

    2012-01-01

    Tubby and Tubby-like proteins (TLPs) were first discovered in mammals, where they are involved in the development and function of neuronal cells. Due to their importance as plasma membrane (PM)-tethered transcription factors or mediators of vesicle trafficking, their lack causes obesity and other disease syndromes. Phosphatidylinositol 4,5-bisphosphate binding of the carboxyl-terminal Tubby domain attaches these proteins to the PM and vesicles and is essential for function. TLPs are conserved across eukaryotic kingdoms including plants, suggesting fundamental biological functions of TLPs. Plant TLPs possess an amino-terminal F-box domain that distinguishes them from other eukaryotic TLPs. Arabidopsis (Arabidopsis thaliana) encodes 11 AtTLPs that fall into six phylogenetic clades. We identified the significance of AtTLPs for root colonization of Arabidopsis by the mutualistic fungus Piriformospora indica. Our results further indicate conserved phosphatidylinositol 4,5-bisphosphate-binding sites in the Tubby domains that are required for PM anchoring of AtTLPs. More detailed studies revealed phospholipase C-triggered release of AtTLP3 from the PM, indicating a conserved mechanism as reported for mammalian Tubby and TLP3. We further show that hydrogen peroxide stimulates the release of AtTLP3 from the PM, presumably for activating downstream events. Different from mammalian homologs, the amino-terminal part of almost all AtTLPs has nucleocytosolic and plastidial localization patterns. Thus, it is tempting to assume that TLPs translate reactive oxygen species currents into signaling not only for transcriptional regulation in the nucleus but also affect plastid-associated functions after release from the PM. PMID:22751378

  16. The subcellular localization of Tubby-like proteins and participation in stress signaling and root colonization by the mutualist Piriformospora indica.

    Science.gov (United States)

    Reitz, Marco Uwe; Bissue, Jeff Kweku; Zocher, Kathleen; Attard, Agnès; Hückelhoven, Ralph; Becker, Katja; Imani, Jafargholi; Eichmann, Ruth; Schäfer, Patrick

    2012-09-01

    Tubby and Tubby-like proteins (TLPs) were first discovered in mammals, where they are involved in the development and function of neuronal cells. Due to their importance as plasma membrane (PM)-tethered transcription factors or mediators of vesicle trafficking, their lack causes obesity and other disease syndromes. Phosphatidylinositol 4,5-bisphosphate binding of the carboxyl-terminal Tubby domain attaches these proteins to the PM and vesicles and is essential for function. TLPs are conserved across eukaryotic kingdoms including plants, suggesting fundamental biological functions of TLPs. Plant TLPs possess an amino-terminal F-box domain that distinguishes them from other eukaryotic TLPs. Arabidopsis (Arabidopsis thaliana) encodes 11 AtTLPs that fall into six phylogenetic clades. We identified the significance of AtTLPs for root colonization of Arabidopsis by the mutualistic fungus Piriformospora indica. Our results further indicate conserved phosphatidylinositol 4,5-bisphosphate-binding sites in the Tubby domains that are required for PM anchoring of AtTLPs. More detailed studies revealed phospholipase C-triggered release of AtTLP3 from the PM, indicating a conserved mechanism as reported for mammalian Tubby and TLP3. We further show that hydrogen peroxide stimulates the release of AtTLP3 from the PM, presumably for activating downstream events. Different from mammalian homologs, the amino-terminal part of almost all AtTLPs has nucleocytosolic and plastidial localization patterns. Thus, it is tempting to assume that TLPs translate reactive oxygen species currents into signaling not only for transcriptional regulation in the nucleus but also affect plastid-associated functions after release from the PM.

  17. HECTAR: a method to predict subcellular targeting in heterokonts.

    Science.gov (United States)

    Gschloessl, Bernhard; Guermeur, Yann; Cock, J Mark

    2008-09-23

    The heterokonts are a particularly interesting group of eukaryotic organisms; they include many key species of planktonic and coastal algae and several important pathogens. To understand the biology of these organisms, it is necessary to be able to predict the subcellular localisation of their proteins but this is not straightforward, particularly in photosynthetic heterokonts which possess a complex chloroplast, acquired as the result of a secondary endosymbiosis. This is because the bipartite target peptides that deliver proteins to these chloroplasts can be easily confused with the signal peptides of secreted proteins, causing currently available algorithms to make erroneous predictions. HECTAR, a subcellular targeting prediction method which takes into account the specific properties of heterokont proteins, has been developed to address this problem. HECTAR is a statistical prediction method designed to assign proteins to five different categories of subcellular targeting: Signal peptides, type II signal anchors, chloroplast transit peptides, mitochondrion transit peptides and proteins which do not possess any N-terminal target peptide. The recognition rate of HECTAR is 96.3%, with Matthews correlation coefficients ranging from 0.67 to 0.95. The method is based on a hierarchical architecture which implements the divide and conquer approach to identify the different possible target peptides one at a time. At each node of the hierarchy, the most relevant outputs of various existing subcellular prediction methods are combined by a Support Vector Machine. The HECTAR method is able to predict the subcellular localisation of heterokont proteins with high accuracy. It also efficiently predicts the subcellular localisation of proteins from cryptophytes, a group that is phylogenetically close to the heterokonts. A variant of HECTAR, called HECTARSEC, can be used to identify signal peptide and type II signal anchor sequences in proteins from any eukaryotic organism. Both

  18. HECTAR: A method to predict subcellular targeting in heterokonts

    Directory of Open Access Journals (Sweden)

    Guermeur Yann

    2008-09-01

    Full Text Available Abstract Background The heterokonts are a particularly interesting group of eukaryotic organisms; they include many key species of planktonic and coastal algae and several important pathogens. To understand the biology of these organisms, it is necessary to be able to predict the subcellular localisation of their proteins but this is not straightforward, particularly in photosynthetic heterokonts which possess a complex chloroplast, acquired as the result of a secondary endosymbiosis. This is because the bipartite target peptides that deliver proteins to these chloroplasts can be easily confused with the signal peptides of secreted proteins, causing currently available algorithms to make erroneous predictions. HECTAR, a subcellular targeting prediction method which takes into account the specific properties of heterokont proteins, has been developed to address this problem. Results HECTAR is a statistical prediction method designed to assign proteins to five different categories of subcellular targeting: Signal peptides, type II signal anchors, chloroplast transit peptides, mitochondrion transit peptides and proteins which do not possess any N-terminal target peptide. The recognition rate of HECTAR is 96.3%, with Matthews correlation coefficients ranging from 0.67 to 0.95. The method is based on a hierarchical architecture which implements the divide and conquer approach to identify the different possible target peptides one at a time. At each node of the hierarchy, the most relevant outputs of various existing subcellular prediction methods are combined by a Support Vector Machine. Conclusion The HECTAR method is able to predict the subcellular localisation of heterokont proteins with high accuracy. It also efficiently predicts the subcellular localisation of proteins from cryptophytes, a group that is phylogenetically close to the heterokonts. A variant of HECTAR, called HECTARSEC, can be used to identify signal peptide and type II signal

  19. Global targeting of subcellular heat shock protein-90 networks for therapy of glioblastoma.

    Science.gov (United States)

    Siegelin, Markus D; Plescia, Janet; Raskett, Christopher M; Gilbert, Candace A; Ross, Alonzo H; Altieri, Dario C

    2010-06-01

    Drug discovery for complex and heterogeneous tumors now aims at dismantling global networks of disease maintenance, but the subcellular requirements of this approach are not understood. Here, we simultaneously targeted the multiple subcellular compartments of the molecular chaperone heat shock protein-90 (Hsp90) in a model of glioblastoma, a highly lethal human malignancy in urgent need of fresh therapeutic strategies. Treatment of cultured or patient-derived glioblastoma cells with Shepherdin, a dual peptidomimetic inhibitor of mitochondrial and cytosolic Hsp90, caused irreversible collapse of mitochondria, degradation of Hsp90 client proteins in the cytosol, and tumor cell killing by apoptosis and autophagy. Stereotactic or systemic delivery of Shepherdin was well tolerated and suppressed intracranial glioma growth via inhibition of cell proliferation, induction of apoptosis, and reduction of angiogenesis in vivo. These data show that disabling Hsp90 cancer networks in their multiple subcellular compartments improves strategies for drug discovery and may provide novel molecular therapy for highly recalcitrant human tumors.

  20. Compartment Syndrome in Children.

    Science.gov (United States)

    Hosseinzadeh, Pooya; Hayes, Christopher B

    2016-07-01

    Compartment syndrome in children can present differently than adults. Increased analgesic need should be considered the first sign of evolving compartment syndrome in children. Children with supracondylar humerus fractures, floating elbow injuries, operatively treated forearm fractures, and tibia fractures are at high risk for developing compartment syndrome. Elbow flexion beyond 90° in supracondylar humerus fractures and closed treatment of forearm fractures in floating elbow injuries are associated with increased risk of compartment syndrome. Prompt diagnosis and treatment with fasciotomy in children result in excellent long-term outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Analysis of subcellular metabolite distributions within Arabidopsis thaliana leaf tissue: a primer for subcellular metabolomics.

    Science.gov (United States)

    Krueger, Stephan; Steinhauser, Dirk; Lisec, Jan; Giavalisco, Patrick

    2014-01-01

    Every biological organism relies for its proper function on interactions between a multitude of molecular entities like RNA, proteins, and metabolites. The comprehensive measurement and the analysis of all these entities would therefore provide the basis for our functional and mechanistic understanding of most biological processes. Next to their amount and identity, it is most crucial to also gain information about the subcellular distribution and the flux of the measured compounds between the cellular compartments. That is, we want to understand not only the individual functions of cellular components but also their functional implications within the whole organism. While the analysis of macromolecules like DNA, RNA, and proteins is quite established and robust, analytical techniques for small metabolites, which are prone to diffusion and degradation processes, provide a host of unsolved challenges. The major limitations here are the metabolite conversion and relocation processes. In this protocol we describe a methodological workflow which includes a nonaqueous fractionation method, a fractionated two-phase liquid/liquid extraction protocol, and a software package, which together allow extracting and analyzing starch, proteins, and especially polar and lipophilic metabolites from a single sample towards the estimation of their subcellular distributions.

  2. Subcellular location of PKA controls striatal plasticity: stochastic simulations in spiny dendrites.

    Directory of Open Access Journals (Sweden)

    Rodrigo F Oliveira

    2012-02-01

    Full Text Available Dopamine release in the striatum has been implicated in various forms of reward dependent learning. Dopamine leads to production of cAMP and activation of protein kinase A (PKA, which are involved in striatal synaptic plasticity and learning. PKA and its protein targets are not diffusely located throughout the neuron, but are confined to various subcellular compartments by anchoring molecules such as A-Kinase Anchoring Proteins (AKAPs. Experiments have shown that blocking the interaction of PKA with AKAPs disrupts its subcellular location and prevents LTP in the hippocampus and striatum; however, these experiments have not revealed whether the critical function of anchoring is to locate PKA near the cAMP that activates it or near its targets, such as AMPA receptors located in the post-synaptic density. We have developed a large scale stochastic reaction-diffusion model of signaling pathways in a medium spiny projection neuron dendrite with spines, based on published biochemical measurements, to investigate this question and to evaluate whether dopamine signaling exhibits spatial specificity post-synaptically. The model was stimulated with dopamine pulses mimicking those recorded in response to reward. Simulations show that PKA colocalization with adenylate cyclase, either in the spine head or in the dendrite, leads to greater phosphorylation of DARPP-32 Thr34 and AMPA receptor GluA1 Ser845 than when PKA is anchored away from adenylate cyclase. Simulations further demonstrate that though cAMP exhibits a strong spatial gradient, diffusible DARPP-32 facilitates the spread of PKA activity, suggesting that additional inactivation mechanisms are required to produce spatial specificity of PKA activity.

  3. ACUTE COMPARTMENT SYNDROME

    African Journals Online (AJOL)

    student's MNEMONIC 5ps of ACS). The clinical diagnosis can be confirmed by compartment pressure measurements (2,6,7) and the treatment is urgent decompression by fasciotomy. Patients with compartment syndrome should be treated with utmost urgency, constant monitoring, and early decompression with appropriate ...

  4. brain compartment syndrome

    African Journals Online (AJOL)

    Compartment syndrome of the limbs or the abdomen is a well-known entity in general surgical and orthopaedic practice, characterised by an increase of pressure within a musculofascial compartment leading to progressive neurovascular dysfunction. Although it has not been described as such, raised pressure within the ...

  5. Subcellular localization prediction through boosting association rules.

    Science.gov (United States)

    Yoon, Yongwook; Lee, Gary Geunbae

    2012-01-01

    Computational methods for predicting protein subcellular localization have used various types of features, including N-terminal sorting signals, amino acid compositions, and text annotations from protein databases. Our approach does not use biological knowledge such as the sorting signals or homologues, but use just protein sequence information. The method divides a protein sequence into short $k$-mer sequence fragments which can be mapped to word features in document classification. A large number of class association rules are mined from the protein sequence examples that range from the N-terminus to the C-terminus. Then, a boosting algorithm is applied to those rules to build up a final classifier. Experimental results using benchmark datasets show our method is excellent in terms of both the classification performance and the test coverage. The result also implies that the $k$-mer sequence features which determine subcellular locations do not necessarily exist in specific positions of a protein sequence. Online prediction service implementing our method is available at http://isoft.postech.ac.kr/research/BCAR/subcell.

  6. Predicting Subcellular Localization of Proteins by Bioinformatic Algorithms

    DEFF Research Database (Denmark)

    Nielsen, Henrik

    2015-01-01

    When predicting the subcellular localization of proteins from their amino acid sequences, there are basically three approaches: signal-based, global property-based, and homology-based. Each of these has its advantages and drawbacks, and it is important when comparing methods to know which approac...

  7. Lysosome-related organelles: Unusual compartments become mainstream

    OpenAIRE

    Marks, Michael S.; Heijnen, Harry F. G.; Raposo, Graça

    2013-01-01

    Lysosome-related organelles (LROs) comprise a group of cell type-specific subcellular compartments with unique composition, morphology and structure that share some features with endosomes and lysosomes and that function in varied processes such as pigmentation, hemostasis, lung plasticity and immunity. In recent years, studies of genetic diseases in which LRO functions are compromised have provided new insights into the mechanisms of LRO biogenesis and the regulated secretion of LRO contents...

  8. DNA Virus Replication Compartments

    Science.gov (United States)

    Schmid, Melanie; Speiseder, Thomas; Dobner, Thomas

    2014-01-01

    Viruses employ a variety of strategies to usurp and control cellular activities through the orchestrated recruitment of macromolecules to specific cytoplasmic or nuclear compartments. Formation of such specialized virus-induced cellular microenvironments, which have been termed viroplasms, virus factories, or virus replication centers, complexes, or compartments, depends on molecular interactions between viral and cellular factors that participate in viral genome expression and replication and are in some cases associated with sites of virion assembly. These virus-induced compartments function not only to recruit and concentrate factors required for essential steps of the viral replication cycle but also to control the cellular mechanisms of antiviral defense. In this review, we summarize characteristic features of viral replication compartments from different virus families and discuss similarities in the viral and cellular activities that are associated with their assembly and the functions they facilitate for viral replication. PMID:24257611

  9. Chronic Exertional Compartment Syndrome.

    Science.gov (United States)

    Braver, Richard T

    2016-04-01

    Increased tissue pressure within a fascial compartment may be the result from any increase in volume within its contents, or any decrease in size of the fascial covering or its distensibility. This may lead to symptoms of leg tightness, pain or numbness brought about by exercise. There are multiple differential diagnoses of exercise induced leg pain and the proper diagnoses of chronic exertional compartment syndrome (CECS) is made by a careful history and by exclusion of other maladies and confirmed by compartment syndrome testing as detailed in this text. Surgical fasciotomies for the anterior, lateral, superficial and deep posterior compartments are described in detail along with ancillary procedures for chronic shin splints that should allow the athlete to return to competitive activity. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Abdominal Compartment Syndrome

    Directory of Open Access Journals (Sweden)

    Pınar Zeyneloğlu

    2015-04-01

    Full Text Available Intraabdominal hypertension and Abdominal compartment syndrome are causes of morbidity and mortality in critical care patients. Timely diagnosis and treatment may improve organ functions. Intra-abdominal pressure monitoring is vital during evaluation of the patients and in the management algorithms. The incidence, definition and risk factors, clinical presentation, diagnosis and management of intraabdominal hypertension and Abdominal compartment syndrome were reviewed here.

  11. Programmed subcellular release to study the dynamics of cell detachment

    Science.gov (United States)

    Wildt, Bridget

    Cell detachment is central to a broad range of physio-pathological changes however there are no quantitative methods to study this process. Here we report programmed subcellular release, a method for spatially and temporally controlled cellular detachment and present the first quantitative results of the detachment dynamics of 3T3 fibroblasts at the subcellular level. Programmed subcellular release is an in vitro technique designed to trigger the detachment of distinct parts of a single cell from a patterned substrate with both spatial and temporal control. Subcellular release is achieved by plating cells on an array of patterned gold electrodes created by standard microfabrication techniques. The electrodes are biochemically functionalized with an adhesion-promoting RGD peptide sequence that is attached to the gold electrode via a thiol linkage. Each electrode is electrically isolated so that a subcellular section of a single cell spanning multiple electrodes can be released independently. Upon application of a voltage pulse to a single electrode, RGD-thiol molecules on an individual electrode undergo rapid electrochemical desorption that leads to subsequent cell contraction. The dynamics of cell contraction are found to have characteristic induction and contraction times. This thesis presents the first molecular inhibition studies conducted using programmed subcellular release verifying that this technique can be used to study complex signaling pathways critical to cell motility. Molecular level dynamics of focal adhesion proteins and actin stress fibers provide some insight into the complexities associated with triggered cell detachment. In addition to subcellular release, the programmed release of alkanethiols provides a tool for to study the spatially and temporally controlled release of small molecules or particles from individually addressable gold electrodes. Here we report on experiments which determine the dynamics of programmed release using fluorophore

  12. The Subcellular Distribution of Small Molecules: from Pharmacokinetics to Synthetic Biology

    Science.gov (United States)

    Zheng, Nan; Tsai, Hobart Ng; Zhang, Xinyuan; Rosania, Gus R.

    2011-01-01

    The systemic pharmacokinetics and pharmacodynamics of small molecules are determined by subcellular transport phenomena. Although approaches used to study the subcellular distribution of small molecules have gradually evolved over the past several decades, experimental analysis and prediction of cellular pharmacokinetics remains a challenge. In this article, we surveyed the progress of subcellular distribution research since the 1960s, with a focus on the advantages, disadvantages and limitations of the various experimental techniques. Critical review of the existing body of knowledge pointed to many opportunities to advance the rational design of organelle-targeted chemical agents. These opportunities include: 1) development of quantitative, nonfluorescence-based, whole cell methods and techniques to measure the subcellular distribution of chemical agents in multiple compartments; 2) exploratory experimentation with nonspecific transport probes that have not been enriched with putative, organelle-targeting features; 3) elaboration of hypothesis-driven, mechanistic and modeling-based approaches to guide experiments aimed at elucidating subcellular distribution and transport; and 4) introduction of revolutionary conceptual approaches borrowed from the field of synthetic biology combined with cutting edge experimental strategies. In our laboratory, state-of-the-art subcellular transport studies are now being aimed at understanding the formation of new intracellular membrane structures in response to drug therapy, exploring the function of drug-membrane complexes as intracellular drug depots, and synthesizing new organelles with extraordinary physical and chemical properties. PMID:21805990

  13. Subcellular partitioning of metals in Aporrectodea caliginosa along a gradient of metal exposure in 31 field-contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Beaumelle, Léa [INRA, UR 251 PESSAC, 78026 Versailles Cedex (France); Gimbert, Frédéric [Laboratoire Chrono-Environnement, UMR 6249 University of Franche-Comté/CNRS Usc INRA, 16 route de Gray, 25030 Besançon Cedex (France); Hedde, Mickaël [INRA, UR 251 PESSAC, 78026 Versailles Cedex (France); Guérin, Annie [INRA, US 0010 LAS Laboratoire d' analyses des sols, 273 rue de Cambrai, 62000 Arras (France); Lamy, Isabelle, E-mail: lamy@versailles.inra.fr [INRA, UR 251 PESSAC, 78026 Versailles Cedex (France)

    2015-07-01

    Subcellular fractionation of metals in organisms was proposed as a better way to characterize metal bioaccumulation. Here we report the impact of a laboratory exposure to a wide range of field-metal contaminated soils on the subcellular partitioning of metals in the earthworm Aporrectodea caliginosa. Soils moderately contaminated were chosen to create a gradient of soil metal availability; covering ranges of both soil metal contents and of several soil parameters. Following exposure, Cd, Pb and Zn concentrations were determined both in total earthworm body and in three subcellular compartments: cytosolic, granular and debris fractions. Three distinct proxies of soil metal availability were investigated: CaCl{sub 2}-extractable content dissolved content predicted by a semi-mechanistic model and free ion concentration predicted by a geochemical speciation model. Subcellular partitionings of Cd and Pb were modified along the gradient of metal exposure, while stable Zn partitioning reflected regulation processes. Cd subcellular distribution responded more strongly to increasing soil Cd concentration than the total internal content, when Pb subcellular distribution and total internal content were similarly affected. Free ion concentrations were better descriptors of Cd and Pb subcellular distribution than CaCl{sub 2} extractable and dissolved metal concentrations. However, free ion concentrations and soil total metal contents were equivalent descriptors of the subcellular partitioning of Cd and Pb because they were highly correlated. Considering lowly contaminated soils, our results raise the question of the added value of three proxies of metal availability compared to soil total metal content in the assessment of metal bioavailability to earthworm. - Highlights: • Earthworms were exposed to a wide panel of historically contaminated soils • Subcellular partitioning of Cd, Pb and Zn was investigated in earthworms • Three proxies of soil metal availability were

  14. Acute compartment syndrome.

    Science.gov (United States)

    Via, Alessio Giai; Oliva, Francesco; Spoliti, Marco; Maffulli, Nicola

    2015-01-01

    acute compartment syndrome (ACS) is one of the few true emergencies in orthopedics and traumatology. It is a painful condition caused by the increase interstitial pressure (intracompart-mental pressure - ICP) within a closed osteofascial compartment which impair local circulation. It occurs most often in the legs, but it can affects also the arms, hands, feet, and buttocks. It usually develops after a severe injury such as fractures or crush injury, but it can also occurs after a relatively minor injury and it may be iatrogenic. Uncommon causes of ACS have been also described, that suggest surgeons to pay great attention to this serious complication. Diagnosing ACS is difficult in clinical practice, even among expert surgeons. Currently, the diagnosis is made on the basis of physical examination and repeated ICP measures. ICP higher than 30 mmHg of diastolic blood pressure is significant of compartment syndrome. Once diagnosis is made, fasciotomy to release the affected compartment should be performed as early as possible because delayed decompression would lead to irreversible ischemic damage to muscles and peripheral nerves. acute compartment syndrome is a surgical emergency. There is still little consensus among authors about diagnosis and treatment of these serious condition, in particular about the ICP at which fasciotomy is absolutely indicated and the timing of wound closure. New investigations are needed in order to improve diagnosis and treatment of ACS.

  15. Acute compartment syndrome

    Science.gov (United States)

    Via, Alessio Giai; Oliva, Francesco; Spoliti, Marco; Maffulli, Nicola

    2015-01-01

    Summary Background: acute compartment syndrome (ACS) is one of the few true emergencies in orthopedics and traumatology. It is a painful condition caused by the increase interstitial pressure (intracompart-mental pressure – ICP) within a closed osteofascial compartment which impair local circulation. It occurs most often in the legs, but it can affects also the arms, hands, feet, and buttocks. It usually develops after a severe injury such as fractures or crush injury, but it can also occurs after a relatively minor injury and it may be iatrogenic. Uncommon causes of ACS have been also described, that suggest surgeons to pay great attention to this serious complication. Diagnosing ACS is difficult in clinical practice, even among expert surgeons. Currently, the diagnosis is made on the basis of physical examination and repeated ICP measures. ICP higher than 30 mmHg of diastolic blood pressure is significant of compartment syndrome. Once diagnosis is made, fasciotomy to release the affected compartment should be performed as early as possible because delayed decompression would lead to irreversible ischemic damage to muscles and peripheral nerves. Conclusion: acute compartment syndrome is a surgical emergency. There is still little consensus among authors about diagnosis and treatment of these serious condition, in particular about the ICP at which fasciotomy is absolutely indicated and the timing of wound closure. New investigations are needed in order to improve diagnosis and treatment of ACS. PMID:25878982

  16. Genetic manipulation of the ghrelin signaling system in male mice reveals bone compartment specificity of acylated and unacylated ghrelin in the regulation of bone remodeling

    Science.gov (United States)

    Ghrelin receptor-deficient (Ghsr-/-) mice that lack acylated ghrelin (AG) signaling retain a metabolic response to unacylated ghrelin (UAG). Recently, we showed that Ghsr-deficiency affects bone metabolism. The aim of this study was to further establish the impact of AG and UAG on bone metabolism. W...

  17. Spontaneous Thigh Compartment Syndrome

    Directory of Open Access Journals (Sweden)

    Khan, Sameer K

    2011-02-01

    Full Text Available A young man presented with a painful and swollen thigh, without any history of trauma, illness, coagulopathic medication or recent exertional exercise. Preliminary imaging delineated a haematoma in the anterior thigh, without any fractures or muscle trauma. Emergent fasciotomies were performed. No pathology could be identified intra-operatively, or on follow-up imaging. A review of thigh compartment syndromes described in literature is presented in a table. Emergency physicians and traumatologists should be cognisant of spontaneous atraumatic presentations of thigh compartment syndrome, to ensure prompt referral and definitive management of this limb-threatening condition. [West J Emerg Med. 2011;12(1:134-138].

  18. Immunogold labeling reveals subcellular localisation of silica nanoparticles in a human blood-brain barrier model

    Science.gov (United States)

    Ye, Dong; Anguissola, Sergio; O'Neill, Tiina; Dawson, Kenneth A.

    2015-05-01

    Subcellular location of nanoparticles has been widely investigated with fluorescence microscopy, via fluorescently labeled antibodies to visualise target antigens in cells. However, fluorescence microscopy, such as confocal or live cell imaging, has generally limited 3D spatial resolution. Conventional electron microscopy can be useful in bridging resolution gap, but still not ideal in resolving subcellular organelle identities. Using the pre-embedding immunogold electron microscopic imaging, we performed accurate examination of the intracellular trafficking and gathered further evidence of transport mechanisms of silica nanoparticles across a human in vitro blood-brain barrier model. Our approach can effectively immunolocalise a variety of intracellular compartments and provide new insights into the uptake and subcellular transport of nanoparticles.Subcellular location of nanoparticles has been widely investigated with fluorescence microscopy, via fluorescently labeled antibodies to visualise target antigens in cells. However, fluorescence microscopy, such as confocal or live cell imaging, has generally limited 3D spatial resolution. Conventional electron microscopy can be useful in bridging resolution gap, but still not ideal in resolving subcellular organelle identities. Using the pre-embedding immunogold electron microscopic imaging, we performed accurate examination of the intracellular trafficking and gathered further evidence of transport mechanisms of silica nanoparticles across a human in vitro blood-brain barrier model. Our approach can effectively immunolocalise a variety of intracellular compartments and provide new insights into the uptake and subcellular transport of nanoparticles. Electronic supplementary information (ESI) available: Nanoparticle characterisation data, preservation of cellular structures, staining controls, optimisation of size amplification via the silver enhancement, and more imaging results from anti-clathrin and anti-caveolin 1

  19. Subcellular Redox Targeting: Bridging in Vitro and in Vivo Chemical Biology.

    Science.gov (United States)

    Long, Marcus J C; Poganik, Jesse R; Ghosh, Souradyuti; Aye, Yimon

    2017-03-17

    Networks of redox sensor proteins within discrete microdomains regulate the flow of redox signaling. Yet, the inherent reactivity of redox signals complicates the study of specific redox events and pathways by traditional methods. Herein, we review designer chemistries capable of measuring flux and/or mimicking subcellular redox signaling at the cellular and organismal level. Such efforts have begun to decipher the logic underlying organelle-, site-, and target-specific redox signaling in vitro and in vivo. These data highlight chemical biology as a perfect gateway to interrogate how nature choreographs subcellular redox chemistry to drive precision redox biology.

  20. Neonatal compartment syndrome.

    Science.gov (United States)

    Martin, B; Treharne, L

    2016-09-01

    A term neonate was born with a grossly swollen and discoloured left hand and forearm. He was transferred from the local hospital to the plastic surgical unit, where a diagnosis of compartment syndrome was made and he underwent emergency forearm fasciotomies at six hours of age. Following serial debridements of necrotic tissue, he underwent split-thickness skin grafting of the resultant defects of his forearm, hand and digits. At the clinic follow-up appointment two months after the procedure, he was found to have developed severe flexion contractures despite regular outpatient hand therapy and splintage. He has had further reconstruction with contracture release, use of artificial dermal matrix, and K-wire fixation of the thumb and wrist. Despite this, the long term outcome is likely to be an arm with poor function. The key learning point from this case is that despite prompt transfer, diagnosis and appropriate surgical management, the outcome for neonatal compartment syndrome may still be poor.

  1. Iliopsoas compartment lesions: a radiologic evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Leao, Alberto Ribeiro de Souza; Amaral, Raquel Portugal Guimaraes; Abud, Thiago Giansante; Demarchi, Guilherme Tadeu Sauaia; Freire Filho, Edison de Oliveira; Novack, Paulo Rogerio; Campos, Flavio do Amaral; Shigueoka, David Carlos; Fernandes, Artur da Rocha Correa; Szejnfeld, Jacob; D' Ippolito, Giuseppe [Universidade Federal de Sao Paulo (UNIFESP-EPM), Sao Paulo, SP (Brazil). Dept. de Diagnostico por Imagem]. E-mail: ar.leao@uol.com.br; Santos, Jose Eduardo Mourao [Universidade Federal de Sao Paulo (UNIFESP-EPM), Sao Paulo, SP (Brazil)

    2007-07-15

    The iliopsoas compartment, a posterior boundary of the retroperitoneum, is comprised of the psoas major, psoas minor and iliac muscles. The symptoms picture in patients presenting with pathological involvement of this compartment may show a wide range of nonspecific clinical presentations that may lead to delayed diagnosis. However, in the search of an etiological diagnosis, it is already known that inflammation, tumors, and hemorrhages account for almost all the lesions affecting the iliopsoas compartment. By means of a retrospective analysis of radiological studies in patients with iliopsoas compartment lesions whose diagnosis was confirmed by anatomopathological evaluation or clinical follow-up, we have reviewed its anatomy as well as the main forms of involvement, with the purpose of identifying radiological signs that may help to narrow down the potential differential diagnoses. As each lesion is approached we will discuss the main radiological findings such as presence of gas in pyogenic abscesses, bone destruction and other bone changes of vertebral bodies in lesions secondary to tuberculosis, involvement of fascial planes in cases of neoplasms, and differences in signal density and intensity of hematomas secondary to hemoglobin degradation, among others. So, we have tried to present cases depicting the most frequent lesions involving the iliopsoas compartment, with emphasis on those signs that can lead us to a more specific etiological diagnosis. (author)

  2. Genetically targeted fluorogenic macromolecules for subcellular imaging and cellular perturbation.

    Science.gov (United States)

    Magenau, Andrew J D; Saurabh, Saumya; Andreko, Susan K; Telmer, Cheryl A; Schmidt, Brigitte F; Waggoner, Alan S; Bruchez, Marcel P

    2015-10-01

    The alteration of cellular functions by anchoring macromolecules to specified organelles may reveal a new area of therapeutic potential and clinical treatment. In this work, a unique phenotype was evoked by influencing cellular behavior through the modification of subcellular structures with genetically targetable macromolecules. These fluorogen-functionalized polymers, prepared via controlled radical polymerization, were capable of exclusively decorating actin, cytoplasmic, or nuclear compartments of living cells expressing localized fluorgen-activating proteins. The macromolecular fluorogens were optimized by establishing critical polymer architecture-biophysical property relationships which impacted binding rates, binding affinities, and the level of internalization. Specific labeling of subcellular structures was realized at nanomolar concentrations of polymer, in the absence of membrane permeabilization or transduction domains, and fluorogen-modified polymers were found to bind to protein intact after delivery to the cytosol. Cellular motility was found to be dependent on binding of macromolecular fluorogens to actin structures causing rapid cellular ruffling without migration. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Subcellular targeting: a new frontier for drug-loaded pharmaceutical nanocarriers and the concept of the magic bullet.

    Science.gov (United States)

    D'Souza, Gerard G M; Weissig, Volkmar

    2009-11-01

    The ability of a pharmacologically active molecule selectively to find its target is closely linked with its potential as a successful therapeutic drug. It has become increasingly evident that there are several pharmacologically active molecules that exert their action on molecular targets inside cell organelles. In the case of a drug molecule with no defined specificity for a particular organelle, the molecule would either need to have sufficiently long metabolic stability to allow for random interaction with the organelle to occur, or a targeting strategy for the intended subcellular compartment would need to be devised in order to potentiate therapeutic effect. In the case of molecules with a stronger affinity for a non-target subcellular compartment, there exists even greater need for the ability to control subcellular disposition. Subcellular or organelle-specific targeting has thus emerged as a new frontier in drug delivery. In this review selected examples of recent work are discussed that the authors believe might eventually lead to the application of pharmaceutical nanocarriers to create the next generation of 'magic bullets' that are capable of delivering a drug payload to a molecular target at a subcellular location.

  4. Novel connections in plant organellar signalling link different stress responses and signalling pathways.

    Science.gov (United States)

    Kmiecik, Przemyslaw; Leonardelli, Manuela; Teige, Markus

    2016-06-01

    To coordinate growth, development and responses to environmental stimuli, plant cells need to communicate the metabolic state between different sub-compartments of the cell. This requires signalling pathways, including protein kinases, secondary messengers such as Ca(2+) ions or reactive oxygen species (ROS) as well as metabolites and plant hormones. The signalling networks involved have been intensively studied over recent decades and have been elaborated more or less in detail. However, it has become evident that these signalling networks are also tightly interconnected and often merge at common targets such as a distinct group of transcription factors, most prominently ABI4, which are amenable to regulation by phosphorylation, potentially also in a Ca(2+)- or ROS-dependent fashion. Moreover, the signalling pathways connect several organelles or subcellular compartments, not only in functional but also in physical terms, linking for example chloroplasts to the nucleus or peroxisomes to chloroplasts thereby enabling physical routes for signalling by metabolite exchange or even protein translocation. Here we briefly discuss these novel findings and try to connect them in order to point out the remaining questions and emerging developments in plant organellar signalling. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  5. Anterior vaginal compartment surgery.

    Science.gov (United States)

    Maher, Christopher

    2013-11-01

    To review the safety and efficacy of anterior vaginal compartment pelvic organ prolapse surgery. Every 4 years and as part of the Fifth International Collaboration on Incontinence we reviewed the English-language scientific literature after searching PubMed, Medline, Cochrane library and the Cochrane database of systematic reviews, published up to January 2012. Publications were classified as level 1 evidence (randomised controlled trials [RCT] or systematic reviews), level 2 (poor quality RCT, prospective cohort studies), level 3 (case series or retrospective studies) and level 4 case reports. The highest level of evidence was utilised by the committee to make evidence-based recommendations based upon the Oxford grading system. A grade A recommendation usually depends on consistent level 1 evidence. A grade B recommendation usually depends on consistent level 2 and/or 3 studies, or "majority evidence" from RCTs. A grade C recommendation usually depends on level studies or "majority evidence" from level 2/3 studies or Delphi processed expert opinion. A grade D "no recommendation possible" would be used where the evidence is inadequate or conflicting and when expert opinion is delivered without a formal analytical process, such as by Delphi. Absorbable mesh augmentation of anterior compartment native tissue repair improves the anatomical outcome compared with native tissue repair alone with no increased complication rate in meta-analysis of 2 RCTS (grade B). Biological grafts in meta-analysis have improved anatomical outcomes with no change in subjective outcomes compared with native tissue repairs (grade B). There is conflicting level 1 evidence to support porcine dermis and a single RCT to support small intestine submucosa as graft agents in anterior compartment prolapse surgery (grade B). Consistent level 1 data support a superior anatomical outcome for polypropylene mesh compared with a biological graft in the anterior compartment. Mesh exposure rate was

  6. Compartment syndrome without pain!

    LENUS (Irish Health Repository)

    O'Sullivan, M J

    2012-02-03

    We report the case of a young male patient who underwent intra-medullary nailing for a closed, displaced mid-shaft fracture of tibia and fibula. He was commenced on patient controlled analgesia post-operatively. A diagnosis of compartment syndrome in the patient\\'s leg was delayed because he did not exhibit a pain response. This ultimately resulted in a below-knee amputation of the patient\\'s leg. We caution against the use of patient controlled analgesia in any traumatised limb distal to the hip or the shoulder.

  7. A comparative antibody analysis of Pannexin1 expression in four rat brain regions reveals varying subcellular localizations

    Directory of Open Access Journals (Sweden)

    Angela C Cone

    2013-02-01

    Full Text Available Pannexin1 (Panx1 channels release cytosolic ATP in response to signaling pathways. Panx1 is highly expressed in the central nervous system. We used four antibodies with different Panx1 anti-peptide epitopes to analyze four regions of rat brain. These antibodies labeled the same bands in Western blots and had highly similar patterns of immunofluorescence in tissue culture cells expressing Panx1, but Western blots of brain lysates from Panx1 knockout and control mice showed different banding patterns. Localizations of Panx1 in brain slices were generated using automated wide-field mosaic confocal microscopy for imaging large regions of interest while retaining maximum resolution for examining cell populations and compartments. We compared Panx1 expression over the cerebellum, hippocampus with adjacent cortex, thalamus and olfactory bulb. While Panx1 localizes to the same neuronal cell types, subcellular localizations differ. Two antibodies with epitopes against the intracellular loop and one against the carboxy terminus preferentially labeled cell bodies, while an antibody raised against an N-terminal peptide highlighted neuronal processes more than cell bodies. These labeling patterns may be a reflection of different cellular and subcellular localizations of full-length and/or modified Panx1 channels where each antibody is highlighting unique or differentially accessible Panx1 populations. However, we cannot rule out that one or more of these antibodies have specificity issues. All data associated with experiments from these four antibodies are presented in a manner that allows them to be compared and our claims thoroughly evaluated, rather than eliminating results that were questionable. Each antibody is given a unique identifier through the NIF Antibody Registry that can be used to track usage of individual antibodies across papers and all image and metadata are made available in the public repository, the Cell Centered Database, for on

  8. Multimodal subcellular imaging with microcavity photoacoustic transducer.

    Science.gov (United States)

    Tan, Zhiliang; Tang, Zhilie; Wu, Yongbo; Liao, Yanfei; Dong, Wei; Guo, Lina

    2011-01-31

    Photoacoustic microscopy (PAM) is dominantly sensitive to the endogenous optical absorption compared with the confocal microscopy which images with scattering photons. PAM has similar structure such as optical transportation system, the optical scanning, and light source with the laser scanning confocal microscopy (LSCM). In order to match the PAM with LSCM, a special design microcavity photoacoustic (PA) transducer with high sensitivity is developed to detect the photoacoustic signals induced by modulated continuous wave (CW) laser. By employing a microcavity PA transducer, a PAM can be integrated with LSCM. Thus a simultaneous multimodal imaging can be obtained with the same laser source and optical system. The lateral resolutions of the PAM and the LSCM are both tested to be better than 1.25 μm. Then subcellular multimodal imaging can be achieved. Images from the two modes are corresponding with each other but functionally complementary. Combining PAM and LSCM provides more comprehensive information for the cytological test. This technique is demonstrated for imaging red-blood cells and meristematic cells.

  9. Hydrogen peroxide probes directed to different cellular compartments.

    Directory of Open Access Journals (Sweden)

    Mikalai Malinouski

    2011-01-01

    Full Text Available Controlled generation and removal of hydrogen peroxide play important roles in cellular redox homeostasis and signaling. We used a hydrogen peroxide biosensor HyPer, targeted to different compartments, to examine these processes in mammalian cells.Reversible responses were observed to various redox perturbations and signaling events. HyPer expressed in HEK 293 cells was found to sense low micromolar levels of hydrogen peroxide. When targeted to various cellular compartments, HyPer occurred in the reduced state in the nucleus, cytosol, peroxisomes, mitochondrial intermembrane space and mitochondrial matrix, but low levels of the oxidized form of the biosensor were also observed in each of these compartments, consistent with a low peroxide tone in mammalian cells. In contrast, HyPer was mostly oxidized in the endoplasmic reticulum. Using this system, we characterized control of hydrogen peroxide in various cell systems, such as cells deficient in thioredoxin reductase, sulfhydryl oxidases or subjected to selenium deficiency. Generation of hydrogen peroxide could also be monitored in various compartments following signaling events.We found that HyPer can be used as a valuable tool to monitor hydrogen peroxide generated in different cellular compartments. The data also show that hydrogen peroxide generated in one compartment could translocate to other compartments. Our data provide information on compartmentalization, dynamics and homeostatic control of hydrogen peroxide in mammalian cells.

  10. CELLO2GO: a web server for protein subCELlular LOcalization prediction with functional gene ontology annotation.

    Directory of Open Access Journals (Sweden)

    Chin-Sheng Yu

    Full Text Available CELLO2GO (http://cello.life.nctu.edu.tw/cello2go/ is a publicly available, web-based system for screening various properties of a targeted protein and its subcellular localization. Herein, we describe how this platform is used to obtain a brief or detailed gene ontology (GO-type categories, including subcellular localization(s, for the queried proteins by combining the CELLO localization-predicting and BLAST homology-searching approaches. Given a query protein sequence, CELLO2GO uses BLAST to search for homologous sequences that are GO annotated in an in-house database derived from the UniProt KnowledgeBase database. At the same time, CELLO attempts predict at least one subcellular localization on the basis of the species in which the protein is found. When homologs for the query sequence have been identified, the number of terms found for each of their GO categories, i.e., cellular compartment, molecular function, and biological process, are summed and presented as pie charts representing possible functional annotations for the queried protein. Although the experimental subcellular localization of a protein may not be known, and thus not annotated, CELLO can confidentially suggest a subcellular localization. CELLO2GO should be a useful tool for research involving complex subcellular systems because it combines CELLO and BLAST into one platform and its output is easily manipulated such that the user-specific questions may be readily addressed.

  11. Expression and subcellular localization of antiporter regulating ...

    African Journals Online (AJOL)

    Expression and subcellular localization of antiporter regulating protein OsARP in rice induced by submergence, salt and drought stresses. Md Imtiaz Uddin, Maki Kihara, Lina Yin, Mst Farida Perveen, Kiyoshi Tanaka ...

  12. Compartment Syndrome of the Hand.

    Science.gov (United States)

    Oak, Nikhil R; Abrams, Reid A

    2016-07-01

    Hand compartment syndrome has many etiologies; untreated, it has dire functional consequences. Intracompartmental pressure exceeding capillary filling pressure causes decreased tissue perfusion resulting in progressive ischemic death of compartment contents. Clinical findings can evolve. Serial physical examinations are recommended and, if equivocal, interstitial pressure monitoring is indicated. Definitive management is emergent fasciotomies with incisions designed to decompress the involved hand compartments, which could include the thenar, hypothenar, and interosseous compartments, and the carpal tunnel. Careful wound care, edema management, splinting, and hand therapy are critical. Therapy should start early postoperatively, possibly before wound closure. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. A novel bipartite UNC-101/AP-1 μ1 binding signal mediates KVS-4/Kv2.1 somatodendritic distribution in Caenorhabditis elegans.

    Science.gov (United States)

    Zhou, Xin; Zeng, Jia; Ouyang, Chenxi; Luo, Qianyun; Yu, Miao; Yang, Zhenrong; Wang, Hui; Shen, Kang; Shi, Anbing

    2016-01-01

    Potassium channels such as Kv2.1 are targeted to specific subcellular compartments to fulfill various functions. However, the mechanisms for their localization are poorly understood. Here, we show that KVS-4/Kv2.1 somatodendritic localization in Caenorhabditis elegansDA9 neuron requires UNC-101(AP-1 μ subunit). We define a bipartite sorting signal within KVS-4 consisting of a C-terminal EQMIL and N-terminal WNIIE motifs. The bipartite signal is sufficient to target nonpolarized transmembrane protein MIG-13 into DA9 somatodendritic compartments. Furthermore, we found that AP-1 interacts with the bipartite signal through UNC-101/AP-1 μ N-terminal predicted Longin-like domain. Our results provide new insight into the mechanisms of Kv2.1 post-Golgi sorting and targeting. © 2015 Federation of European Biochemical Societies.

  14. Differential subcellular distribution of ion channels and the diversity of neuronal function.

    Science.gov (United States)

    Nusser, Zoltan

    2012-06-01

    Following the astonishing molecular diversity of voltage-gated ion channels that was revealed in the past few decades, the ion channel repertoire expressed by neurons has been implicated as the major factor governing their functional heterogeneity. Although the molecular structure of ion channels is a key determinant of their biophysical properties, their subcellular distribution and densities on the surface of nerve cells are just as important for fulfilling functional requirements. Recent results obtained with high resolution quantitative localization techniques revealed complex, subcellular compartment-specific distribution patterns of distinct ion channels. Here I suggest that within a given neuron type every ion channel has a unique cell surface distribution pattern, with the functional consequence that this dramatically increases the computational power of nerve cells. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. CoBaltDB: Complete bacterial and archaeal orfeomes subcellular localization database and associated resources

    Directory of Open Access Journals (Sweden)

    Lucchetti-Miganeh Céline

    2010-03-01

    Full Text Available Abstract Background The functions of proteins are strongly related to their localization in cell compartments (for example the cytoplasm or membranes but the experimental determination of the sub-cellular localization of proteomes is laborious and expensive. A fast and low-cost alternative approach is in silico prediction, based on features of the protein primary sequences. However, biologists are confronted with a very large number of computational tools that use different methods that address various localization features with diverse specificities and sensitivities. As a result, exploiting these computer resources to predict protein localization accurately involves querying all tools and comparing every prediction output; this is a painstaking task. Therefore, we developed a comprehensive database, called CoBaltDB, that gathers all prediction outputs concerning complete prokaryotic proteomes. Description The current version of CoBaltDB integrates the results of 43 localization predictors for 784 complete bacterial and archaeal proteomes (2.548.292 proteins in total. CoBaltDB supplies a simple user-friendly interface for retrieving and exploring relevant information about predicted features (such as signal peptide cleavage sites and transmembrane segments. Data are organized into three work-sets ("specialized tools", "meta-tools" and "additional tools". The database can be queried using the organism name, a locus tag or a list of locus tags and may be browsed using numerous graphical and text displays. Conclusions With its new functionalities, CoBaltDB is a novel powerful platform that provides easy access to the results of multiple localization tools and support for predicting prokaryotic protein localizations with higher confidence than previously possible. CoBaltDB is available at http://www.umr6026.univ-rennes1.fr/english/home/research/basic/software/cobalten.

  16. Considerations for extraction of monoclonal antibodies targeted to different subcellular compartments in transgenic tobacco plants.

    Science.gov (United States)

    Hassan, Sally; van Dolleweerd, Craig J; Ioakeimidis, Fotis; Keshavarz-Moore, Eli; Ma, Julian K-C

    2008-09-01

    Monoclonal antibody production from transgenic tobacco plants offers many advantages over other heterologous production systems, creating the prospect of production at a scale that will allow new prophylactic and therapeutic applications in global human and animal health. However, information on the major processing factors to consider for large-scale purification of antibodies from transgenic plants is currently limited, and is in urgent need of attention. The purpose of this project was to investigate methods for the initial extraction of recombinant immunoglobulin G (IgG) antibodies from transgenic tobacco leaf tissue. Three different transgenic plant lines were studied in order to establish the parameters for optimal extraction of monoclonal antibodies that accumulate in the apoplasm, at the plasma membrane or within the endoplasmic reticulum. For each transgenic line, seven techniques for physical extraction were compared. The factors that determine the optimal extraction of antibodies from plants have a direct influence on the initial choice of expression strategy, and so must be considered at an early stage. The use of small-scale techniques that are applicable to large-scale purification was a particularly important consideration. The optimal extraction technique varied with the target location of IgG in the plant cell, and the dependence of antibody yield on the physical extraction methodology employed, the pH of the extraction buffer and the extraction temperature was demonstrated in each case. The addition of detergent to the extraction buffer may improve the yield, but this was found to be dependent on the site of accumulation of IgG within the plant cell.

  17. Thyroid states regulate subcellular glucose phosphorylation activity in male mice

    Directory of Open Access Journals (Sweden)

    Flavia Letícia Martins Peçanha

    2017-07-01

    Full Text Available The thyroid hormones (THs, triiodothyronine (T3 and thyroxine (T4, are very important in organism metabolism and regulate glucose utilization. Hexokinase (HK is responsible for the first step of glycolysis, catalyzing the conversion of glucose to glucose 6-phosphate. HK has been found in different cellular compartments, and new functions have been attributed to this enzyme. The effects of hyperthyroidism on subcellular glucose phosphorylation in mouse tissues were examined. Tissues were removed, subcellular fractions were isolated from eu- and hyperthyroid (T3, 0.25 μg/g, i.p. during 21 days mice and HK activity was assayed. Glucose phosphorylation was increased in the particulate fraction in soleus (312.4% ± 67.1, n = 10, gastrocnemius (369.2% ± 112.4, n = 10 and heart (142.2% ± 13.6, n = 10 muscle in the hyperthyroid group compared to the control group. Hexokinase activity was not affected in brain or liver. No relevant changes were observed in HK activity in the soluble fraction for all tissues investigated. Acute T3 administration (single dose of T3, 1.25 μg/g, i.p. did not modulate HK activity. Interestingly, HK mRNA levels remained unchanged and HK bound to mitochondria was increased by T3 treatment, suggesting a posttranscriptional mechanism. Analysis of the AKT pathway showed a 2.5-fold increase in AKT and GSK3B phosphorylation in the gastrocnemius muscle in the hyperthyroid group compared to the euthyroid group. Taken together, we show for the first time that THs modulate HK activity specifically in particulate fractions and that this action seems to be under the control of the AKT and GSK3B pathways.

  18. A novel approach to analyze lysosomal dysfunctions through subcellular proteomics and lipidomics: the case of NPC1 deficiency

    Science.gov (United States)

    Tharkeshwar, Arun Kumar; Trekker, Jesse; Vermeire, Wendy; Pauwels, Jarne; Sannerud, Ragna; Priestman, David A.; Te Vruchte, Danielle; Vints, Katlijn; Baatsen, Pieter; Decuypere, Jean-Paul; Lu, Huiqi; Martin, Shaun; Vangheluwe, Peter; Swinnen, Johannes V.; Lagae, Liesbet; Impens, Francis; Platt, Frances M.; Gevaert, Kris; Annaert, Wim

    2017-01-01

    Superparamagnetic iron oxide nanoparticles (SPIONs) have mainly been used as cellular carriers for genes and therapeutic products, while their use in subcellular organelle isolation remains underexploited. We engineered SPIONs targeting distinct subcellular compartments. Dimercaptosuccinic acid-coated SPIONs are internalized and accumulate in late endosomes/lysosomes, while aminolipid-SPIONs reside at the plasma membrane. These features allowed us to establish standardized magnetic isolation procedures for these membrane compartments with a yield and purity permitting proteomic and lipidomic profiling. We validated our approach by comparing the biomolecular compositions of lysosomes and plasma membranes isolated from wild-type and Niemann-Pick disease type C1 (NPC1) deficient cells. While the accumulation of cholesterol and glycosphingolipids is seen as a primary hallmark of NPC1 deficiency, our lipidomics analysis revealed the buildup of several species of glycerophospholipids and other storage lipids in selectively late endosomes/lysosomes of NPC1-KO cells. While the plasma membrane proteome remained largely invariable, we observed pronounced alterations in several proteins linked to autophagy and lysosomal catabolism reflecting vesicular transport obstruction and defective lysosomal turnover resulting from NPC1 deficiency. Thus the use of SPIONs provides a major advancement in fingerprinting subcellular compartments, with an increased potential to identify disease-related alterations in their biomolecular compositions.

  19. LocateP : genome-scale subcellular-location predictor for bacterial proteins

    NARCIS (Netherlands)

    Zhou, M.; Boekhorst, J.; Francke, C.; Siezen, R.J.

    2008-01-01

    BACKGROUND: In the past decades, various protein subcellular-location (SCL) predictors have been developed. Most of these predictors, like TMHMM 2.0, SignalP 3.0, PrediSi and Phobius, aim at the identification of one or a few SCLs, whereas others such as CELLO and Psortb.v.2.0 aim at a broader

  20. Distribution, isomerization and enantiomer selectivity of hexabromocyclododecane (HBCD) diastereoisomers in different tissue and subcellular fractions of earthworms.

    Science.gov (United States)

    Li, Bing; Chen, Hao; Sun, Hongwen; Lan, Zhonghui

    2017-05-01

    In this study, earthworms Eisenia fetida (E. fetida) were exposed to a soil artificially contaminated with individual hexabromocyclododecane (HBCD) diastereoisomers (α-, β- and γ-HBCDs) to investigate the distribution, isomerization and enantiomer selectivity of HBCDs at tissue and subcellular levels. At the tissue level, the concentrations of HBCDs all followed the order of gut>bodyfluid>body wall, which suggested that earthworms accumulated HBCDs mainly via ingesting soil particles. At the subcellular level, the concentrations of HBCDs in an extracellular fraction consisting of granules, tissue fragment, cell membrane and intact cells (fraction A) were higher than those in an intracellular fractions consisting of the microsomal and cytosol (fraction B+C). This confirmed the passive diffusion during the distribution of HBCDs into the intracellular compartment. The distribution proportions of HBCDs varied among different tissue and subcellular fractions, and all changed over time within 14 days. The variable distributions of HBCDs in different fractions were a result of the comprehensive effects of dynamics and thermodynamics processes. The β- and γ-HBCDs were isomerized to α-HBCD in all tissue and subcellular fractions except for fraction C, and the isomerization ratios varied a lot, which seemed to be related to HBCDs residence time. The selective enrichment of (-) α-, (-) β and (-) γ-HBCDs was found in all fractions and this is consistent with that in the whole earthworm. Besides, the extents of enantio-selectivity did not change significantly among different tissue and subcellular fractions. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Compartment Syndrome Following Snake Bite

    National Research Council Canada - National Science Library

    Dhar, Dinesh

    2015-01-01

    .... The local effects of snake bite include tissue necrosis, edema, and compartment syndrome. Patients may also be left with permanent physical deformities due to residual sequelae of the snake bite...

  2. Validating subcellular localization prediction tools with mycobacterial proteins

    Directory of Open Access Journals (Sweden)

    Niño Luis F

    2009-05-01

    Full Text Available Abstract Background The computational prediction of mycobacterial proteins' subcellular localization is of key importance for proteome annotation and for the identification of new drug targets and vaccine candidates. Several subcellular localization classifiers have been developed over the past few years, which have comprised both general localization and feature-based classifiers. Here, we have validated the ability of different bioinformatics approaches, through the use of SignalP 2.0, TatP 1.0, LipoP 1.0, Phobius, PA-SUB 2.5, PSORTb v.2.0.4 and Gpos-PLoc, to predict secreted bacterial proteins. These computational tools were compared in terms of sensitivity, specificity and Matthew's correlation coefficient (MCC using a set of mycobacterial proteins having less than 40% identity, none of which are included in the training data sets of the validated tools and whose subcellular localization have been experimentally confirmed. These proteins belong to the TBpred training data set, a computational tool specifically designed to predict mycobacterial proteins. Results A final validation set of 272 mycobacterial proteins was obtained from the initial set of 852 mycobacterial proteins. According to the results of the validation metrics, all tools presented specificity above 0.90, while dispersion sensitivity and MCC values were above 0.22. PA-SUB 2.5 presented the highest values; however, these results might be biased due to the methodology used by this tool. PSORTb v.2.0.4 left 56 proteins out of the classification, while Gpos-PLoc left just one protein out. Conclusion Both subcellular localization approaches had high predictive specificity and high recognition of true negatives for the tested data set. Among those tools whose predictions are not based on homology searches against SWISS-PROT, Gpos-PLoc was the general localization tool with the best predictive performance, while SignalP 2.0 was the best tool among the ones using a feature

  3. Validating subcellular localization prediction tools with mycobacterial proteins

    Science.gov (United States)

    Restrepo-Montoya, Daniel; Vizcaíno, Carolina; Niño, Luis F; Ocampo, Marisol; Patarroyo, Manuel E; Patarroyo, Manuel A

    2009-01-01

    Background The computational prediction of mycobacterial proteins' subcellular localization is of key importance for proteome annotation and for the identification of new drug targets and vaccine candidates. Several subcellular localization classifiers have been developed over the past few years, which have comprised both general localization and feature-based classifiers. Here, we have validated the ability of different bioinformatics approaches, through the use of SignalP 2.0, TatP 1.0, LipoP 1.0, Phobius, PA-SUB 2.5, PSORTb v.2.0.4 and Gpos-PLoc, to predict secreted bacterial proteins. These computational tools were compared in terms of sensitivity, specificity and Matthew's correlation coefficient (MCC) using a set of mycobacterial proteins having less than 40% identity, none of which are included in the training data sets of the validated tools and whose subcellular localization have been experimentally confirmed. These proteins belong to the TBpred training data set, a computational tool specifically designed to predict mycobacterial proteins. Results A final validation set of 272 mycobacterial proteins was obtained from the initial set of 852 mycobacterial proteins. According to the results of the validation metrics, all tools presented specificity above 0.90, while dispersion sensitivity and MCC values were above 0.22. PA-SUB 2.5 presented the highest values; however, these results might be biased due to the methodology used by this tool. PSORTb v.2.0.4 left 56 proteins out of the classification, while Gpos-PLoc left just one protein out. Conclusion Both subcellular localization approaches had high predictive specificity and high recognition of true negatives for the tested data set. Among those tools whose predictions are not based on homology searches against SWISS-PROT, Gpos-PLoc was the general localization tool with the best predictive performance, while SignalP 2.0 was the best tool among the ones using a feature-based approach. Even though PA-SUB 2

  4. Accurate Classification of Protein Subcellular Localization from High-Throughput Microscopy Images Using Deep Learning

    Directory of Open Access Journals (Sweden)

    Tanel Pärnamaa

    2017-05-01

    Full Text Available High-throughput microscopy of many single cells generates high-dimensional data that are far from straightforward to analyze. One important problem is automatically detecting the cellular compartment where a fluorescently-tagged protein resides, a task relatively simple for an experienced human, but difficult to automate on a computer. Here, we train an 11-layer neural network on data from mapping thousands of yeast proteins, achieving per cell localization classification accuracy of 91%, and per protein accuracy of 99% on held-out images. We confirm that low-level network features correspond to basic image characteristics, while deeper layers separate localization classes. Using this network as a feature calculator, we train standard classifiers that assign proteins to previously unseen compartments after observing only a small number of training examples. Our results are the most accurate subcellular localization classifications to date, and demonstrate the usefulness of deep learning for high-throughput microscopy.

  5. Diagnosis of compartment syndrome using a microwave-based detector

    Science.gov (United States)

    Ling, Geoffrey S. F.; Riechers, Ronald G., Sr.; Pasala, Krishna M.; Blanchard, Jeremy; Rosner, Michael; Jarell, Abel; Yun, Catherine; Garcia-Pinto, Patricia; Song, Ki-Il; Day, Keith; Riechers, Ronald G., Jr.; Zeidman, Seth M.; Rhee, Peter; Ecklund, James M.; Fitzpatrick, Thomas; Lockhart, Stephen

    2002-07-01

    A novel method for identifying compartment syndrome is presented. This method is based on a novel device that uses electromagnetic waves in the microwave radio frequency (RF) region and a modified algorithm previously used for the estimation of the angle of arrival of radar signals. In this study, we employ this radio frequency triage tool (RAFT) to the clinical condition of compartment syndrome, which is a clinical condition where blood or edema in the muscle compartment of the leg leads to critical sichemia of that exptremity. In anesthetized pigs, RAFT, can detect changes in the RF signature from a leg is due to 2cc or greater of either blood or slaine (a surrogate of edema). These results are compared to clinical examination. RAFT is superior to clinical examination in its ability to detect compartment syndrome in pgis.

  6. Subcellular interactions of dietary cadmium, copper and zinc in rainbow trout (Oncorhynchus mykiss)

    Energy Technology Data Exchange (ETDEWEB)

    Kamunde, Collins, E-mail: ckamunde@upei.ca [Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, 550 University Avenue, Charlottetown, PE, C1A 4P3 (Canada); MacPhail, Ruth [Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, 550 University Avenue, Charlottetown, PE, C1A 4P3 (Canada)

    2011-10-15

    Highlights: Interactions of Cu, Cd and Zn were studied at the subcellular level in rainbow trout. Metals accumulated in the liver were predominantly metabolically active. Cd, Cu and Zn exhibited both competitive and cooperative interactions. The metal-metal interactions altered subcellular metals partitioning. - Abstract: Interactions of Cu, Cd and Zn were studied at the subcellular level in juvenile rainbow trout (Oncorhynchus mykiss) fed diets containing ({mu}g/g) 500 Cu, 1000 Zn and 500 Cd singly and as a ternary mixture for 28 days. Livers were harvested and submitted to differential centrifugation to isolate components of metabolically active metal pool (MAP: heat-denaturable proteins (HDP), organelles, nuclei) and metabolically detoxified metal pool (MDP: heat stable proteins (HSP), NaOH-resistant granules). Results indicated that Cd accumulation was enhanced in all the subcellular compartments, albeit at different time points, in fish exposed to the metals mixture relative to those exposed to Cd alone, whereas Cu alone exposure increased Cd partitioning. Exposure to the metals mixture reduced (HDP) and enhanced (HSP, nuclei and granules) Cu accumulation while exposure to Zn alone enhanced Cu concentration in all the fractions analyzed without altering proportional distribution in MAP and MDP. Although subcellular Zn accumulation was less pronounced than that of either Cu or Cd, concentrations of Zn were enhanced in HDP, nuclei and granules from fish exposed to the metals mixture relative to those exposed to Zn alone. Cadmium alone exposure mobilized Zn and Cu from the nuclei and increased Zn accumulation in organelles and Cu in granules, while Cu alone exposure stimulated Zn accumulation in HSP, HDP and organelles. Interestingly, Cd alone exposure increased the partitioning of the three metals in MDP indicative of enhanced detoxification. Generally the accumulated metals were predominantly metabolically active: Cd, 67-83%; Cu, 68-79% and Zn, 60-76%. Taken

  7. Development of a family of redox-sensitive green fluorescent protein indicators for use in relatively oxidizing subcellular environments.

    Science.gov (United States)

    Lohman, Jeremy R; Remington, S James

    2008-08-19

    Green fluorescent protein (GFP) indicators were previously developed that rapidly and quantitatively respond to changes in the thiol/disulfide equilibrium within subcellular compartments. In these indicators, surface-exposed cysteines residues were introduced so as to form a labile redox-active disulfide that in turn controls the emission properties of the internal chromophore. The biosensors have been shown to be effective reporters of the thiol/disulfide status within reducing compartments such as the mitochondria and cytosol for several cell types. However, due to the high thermodynamic stability of the introduced disulfide bond, the indicators are not useful for quantitative analysis within more oxidizing compartments such as the endoplasmic reticulum. Here we report the development of a new family of GFP-based redox indicators (roGFP1-iX) in which the thermodynamic stability of the disulfide is substantially lowered by insertion of a single amino acid into the main chain, adjacent to cysteine 147. The insertions result in indicators with midpoint potentials of -229 to -246 mV and are thus better suited for study of relatively oxidizing subcellular compartments. Atomic resolution crystallographic analyses suggest that two important factors act to destabilize the disulfide linkage in roGFP1-iX. In the oxidized state, an unusual non-proline cis-peptide bond adjacent to one of the cysteines introduces geometric strain into the system, while in the reduced state, a dramatic loop opening lowers the effective concentration of the reacting species.

  8. Expression and subcellular localization of antiporter regulating ...

    African Journals Online (AJOL)

    Md. Imtiaz Uddin

    2012-02-14

    Feb 14, 2012 ... We examined the expression and subcellular localization of antiporter regulating protein OsARP in a submergence tolerant rice (Oryza sativa L.) cultivar FR13A. In the public databases, this protein was designated as putative Os02g0465900 protein. The cDNA containing the full-length sequence of OsARP.

  9. Domains involved in TAF15 subcellular localisation

    DEFF Research Database (Denmark)

    Marko, Marija; Vlassis, Arsenios; Guialis, Apostolia

    2012-01-01

    to play important roles in the onset of specific tumours, certain forms of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). In this study we identified the domains of TAF15 responsible for its subcellular localisation in human (HeLa) cells and experimentally confirmed...

  10. Dual-Compartment Inflatable Suitlock

    Science.gov (United States)

    Kennedy, Kriss J.; Guirgis, Peggy L.; Boyle, Robert M.

    2013-01-01

    There is a need for an improvement over current NASA Extravehicular Activity (EVA) technology. The technology must allow the capacity for quicker, more efficient egress/ingress, allow for shirtsleeve suit maintenance, be compact in transport, and be applicable to environments ranging from planetary surface (partial-g) to orbital or deep space zero-g environments. The technology must also be resistant to dust and other foreign contaminants that may be present on or around a planetary surface. The technology should be portable, and be capable of docking with a variety of habitats, ports, stations, vehicles, and other pressurized modules. The Dual-Compartment Inflatable Suitlock (DCIS) consists of three hard inline bulkheads, separating two cylindrical membrane-walled compartments. The Inner Bulkhead can be fitted with a variety of hatch types, docking flanges, and mating hardware, such as the Common Berthing Mechanism (CBM), for the purpose of mating with vehicles, habitats, and other pressurized modules. The Inner Bulkhead and Center Bulkhead function as the end walls of the Inner Compartment, which during operations, would stay pressurized, either matching the pressure of the habitat or acting as a lower-pressure transitional volume. The Inner Compartment contains donning/doffing fixtures and inner suit-port hatches. The Center Bulkhead has two integrated suit-ports along with a maintenance hatch. The Center Bulkhead and Outer Bulkhead function as the end walls of the Outer Compartment, which stays at vacuum during normal operations. This allows the crewmember to quickly don a suit, and egress the suitlock without waiting for the Outer Compartment to depressurize. The Outer Compartment can be pressurized infrequently for both nominal and off-nominal suit maintenance tasks, allowing shirtsleeve inspections and maintenance/repair of the environmental suits. The Outer Bulkhead has a pressure-assisted hatch door that stays open and stowed during EVA operations, but can

  11. Subcellular localization of calcium deposits during zebrafish (Danio rerio) oogenesis.

    Science.gov (United States)

    Golpour, Amin; Pšenička, Martin; Niksirat, Hamid

    2016-01-01

    Calcium plays prominent roles in regulating a broad range of physiological events in reproduction. The aim of this study was to describe the subcellular distribution of calcium deposits during stages of oogenesis in zebrafish using a combined oxalate-pyroantimonate technique. The oocyte development of zebrafish was categorized into four stages: primary growth, cortical-alveolus, vitellogenic, and maturation, based on morphological criteria. Calcium deposits in the primary growth stage were detected in the cytoplasm, mitochondria, nucleus, and follicular cells. At the cortical-alveolus stage, calcium particles were transported from follicular cells and deposited in the cortical alveoli. In the vitellogenic stage, some cortical alveoli were compacted and transformed from flocculent electron-lucent to electron-dense objects with the progression of the stage. Calcium deposits were transformed from larger to smaller particles, coinciding with compaction of cortical alveoli. In the maturation stage, calcium deposits in all oocyte compartments decreased, with the exception of those in mitochondria. The proportion of area covered by calcium deposits in the mitochondria and cortical alveoli of oocytes at different stages of development was significantly different (poogenesis may contribute to better understanding of its role in oogenesis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Spatiotemporal visualization of subcellular dynamics of carbon nanotubes

    KAUST Repository

    Serag, Maged F.

    2012-12-12

    To date, there is no consensus on the relationship between the physicochemical characteristics of carbon nanotubes (CNTs) and their biological behavior; however, there is growing evidence that the versatile characteristics make their biological fate largely unpredictable and remain an issue of limited knowledge. Here we introduce an experimental methodology for tracking and visualization of postuptake behavior and the intracellular fate of CNTs based on the spatial distribution of diffusion values throughout the plant cell. By using raster scan image correlation spectroscopy (RICS), we were able to generate highly quantitative spatial maps of CNTs diffusion in different cell compartments. The spatial map of diffusion values revealed that the uptake of CNTs is associated with important subcellular events such as carrier-mediated vacuolar transport and autophagy. These results show that RICS is a useful methodology to elucidate the intracellular behavior mechanisms of carbon nanotubes and potentially other fluorescently labeled nanoparticles, which is of relevance for the important issues related to the environmental impact and health hazards. © 2012 American Chemical Society.

  13. Identification of a classic nuclear localization signal at the N terminus that regulates the subcellular localization of Rbfox2 isoforms during differentiation of NMuMG and P19 cells.

    Science.gov (United States)

    Wenzel, Manuel; Schüle, Martin; Casanovas, Sonia; Strand, Dennis; Strand, Susanne; Winter, Jennifer

    2016-12-01

    Nuclear localization of the alternative splicing factor Rbfox2 is achieved by a C-terminal nuclear localization signal (NLS) which can be excluded from some Rbfox2 isoforms by alternative splicing. While this predicts nuclear and cytoplasmic localization, Rbfox2 is exclusively nuclear in some cell types. Here, we identify a second NLS in the N terminus of Rbfox2 isoform 1A that is not included in Rbfox2 isoform 1F. Rbfox2 1A isoforms lacking the C-terminal NLS are nuclear, whereas equivalent 1F isoforms are cytoplasmic. A shift in Rbfox2 expression toward cytoplasmic 1F isoforms occurs during epithelial to mesenchymal transition (EMT) and could be important in regulating the activity and function of Rbfox2. © 2016 Federation of European Biochemical Societies.

  14. Lysosome-related organelles: unusual compartments become mainstream.

    Science.gov (United States)

    Marks, Michael S; Heijnen, Harry F G; Raposo, Graça

    2013-08-01

    Lysosome-related organelles (LROs) comprise a group of cell type-specific subcellular compartments with unique composition, morphology and structure that share some features with endosomes and lysosomes and that function in varied processes such as pigmentation, hemostasis, lung plasticity and immunity. In recent years, studies of genetic diseases in which LRO functions are compromised have provided new insights into the mechanisms of LRO biogenesis and the regulated secretion of LRO contents. These insights have revealed previously unappreciated specialized endosomal sorting processes in all cell types, and are expanding our views of the plasticity of the endosomal and secretory systems in adapting to cell type-specific needs. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Zymogen Activation and Subcellular Activity of Subtilisin Kexin Isozyme 1/Site 1 Protease*

    Science.gov (United States)

    da Palma, Joel Ramos; Burri, Dominique Julien; Oppliger, Joël; Salamina, Marco; Cendron, Laura; de Laureto, Patrizia Polverino; Seidah, Nabil Georges; Kunz, Stefan; Pasquato, Antonella

    2014-01-01

    The proprotein convertase subtilisin kexin isozyme 1 (SKI-1)/site 1 protease (S1P) plays crucial roles in cellular homeostatic functions and is hijacked by pathogenic viruses for the processing of their envelope glycoproteins. Zymogen activation of SKI-1/S1P involves sequential autocatalytic processing of its N-terminal prodomain at sites B′/B followed by the herein newly identified C′/C sites. We found that SKI-1/S1P autoprocessing results in intermediates whose catalytic domain remains associated with prodomain fragments of different lengths. In contrast to other zymogen proprotein convertases, all incompletely matured intermediates of SKI-1/S1P showed full catalytic activity toward cellular substrates, whereas optimal cleavage of viral glycoproteins depended on B′/B processing. Incompletely matured forms of SKI-1/S1P further process cellular and viral substrates in distinct subcellular compartments. Using a cell-based sensor for SKI-1/S1P activity, we found that 9 amino acid residues at the cleavage site (P1–P8) and P1′ are necessary and sufficient to define the subcellular location of processing and to determine to what extent processing of a substrate depends on SKI-1/S1P maturation. In sum, our study reveals novel and unexpected features of SKI-1/S1P zymogen activation and subcellular specificity of activity toward cellular and pathogen-derived substrates. PMID:25378398

  16. Subcellular distribution of non-muscle myosin IIb is controlled by FILIP through Hsc70.

    Directory of Open Access Journals (Sweden)

    Hideshi Yagi

    Full Text Available The neuronal spine is a small, actin-rich dendritic or somatic protrusion that serves as the postsynaptic compartment of the excitatory synapse. The morphology of the spine reflects the activity of the synapse and is regulated by the dynamics of the actin cytoskeleton inside, which is controlled by actin binding proteins such as non-muscle myosin. Previously, we demonstrated that the subcellular localization and function of myosin IIb are regulated by its binding partner, filamin-A interacting protein (FILIP. However, how the subcellular distribution of myosin IIb is controlled by FILIP is not yet known. The objective of this study was to identify potential binding partners of FILIP that contribute to its regulation of non-muscle myosin IIb. Pull-down assays detected a 70-kDa protein that was identified by mass spectrometry to be the chaperone protein Hsc70. The binding of Hsc70 to FILIP was controlled by the adenosine triphosphatase (ATPase activity of Hsc70. Further, FILIP bound to Hsc70 via a domain that was not required for binding non-muscle myosin IIb. Inhibition of ATPase activity of Hsc70 impaired the effect of FILIP on the subcellular distribution of non-muscle myosin IIb. Further, in primary cultured neurons, an inhibitor of Hsc70 impeded the morphological change in spines induced by FILIP. Collectively, these results demonstrate that Hsc70 interacts with FILIP to mediate its effects on non-muscle myosin IIb and to regulate spine morphology.

  17. Subcellular proteomic characterization of the high-temperature stress response of the cyanobacterium Spirulina platensis

    Directory of Open Access Journals (Sweden)

    Cheevadhanarak Supapon

    2009-09-01

    Full Text Available Abstract The present study examined the changes in protein expression in Spirulina platensis upon exposure to high temperature, with the changes in expression analyzed at the subcellular level. In addition, the transcriptional expression level of some differentially expressed proteins, the expression pattern clustering, and the protein-protein interaction network were analyzed. The results obtained from differential expression analysis revealed up-regulation of proteins involved in two-component response systems, DNA damage and repair systems, molecular chaperones, known stress-related proteins, and proteins involved in other biological processes, such as capsule formation and unsaturated fatty acid biosynthesis. The clustering of all differentially expressed proteins in the three cellular compartments showed: (i the majority of the proteins in all fractions were sustained tolerance proteins, suggesting the roles of these proteins in the tolerance to high temperature stress, (ii the level of resistance proteins in the photosynthetic membrane was 2-fold higher than the level in two other fractions, correlating with the rapid inactivation of the photosynthetic system in response to high temperature. Subcellular communication among the three cellular compartments via protein-protein interactions was clearly shown by the PPI network analysis. Furthermore, this analysis also showed a connection between temperature stress and nitrogen and ammonia assimilation.

  18. Localization of O-glycan initiation, sphingomyelin synthesis, and glucosylceramide synthesis in Vero cells with respect to the endoplasmic reticulum-Golgi intermediate compartment

    NARCIS (Netherlands)

    Schweizer, A..; Clausen, H.; van Meer, G.|info:eu-repo/dai/nl/068570368; Hauri, H.P.

    1994-01-01

    The identification of an endoplasmic reticulum-Golgi intermediate compartment (ERGIC), defined by the 53-kDa transmembrane marker protein ERGIC-53, has added to the complexity of the exocytic pathway of higher eukaryotic cells. Recently, a subcellular fractionation procedure was established for the

  19. A compartmentalized mathematical model of the β1-adrenergic signaling system in mouse ventricular myocytes.

    Directory of Open Access Journals (Sweden)

    Vladimir E Bondarenko

    Full Text Available The β1-adrenergic signaling system plays an important role in the functioning of cardiac cells. Experimental data shows that the activation of this system produces inotropy, lusitropy, and chronotropy in the heart, such as increased magnitude and relaxation rates of [Ca(2+]i transients and contraction force, and increased heart rhythm. However, excessive stimulation of β1-adrenergic receptors leads to heart dysfunction and heart failure. In this paper, a comprehensive, experimentally based mathematical model of the β1-adrenergic signaling system for mouse ventricular myocytes is developed, which includes major subcellular functional compartments (caveolae, extracaveolae, and cytosol. The model describes biochemical reactions that occur during stimulation of β1-adrenoceptors, changes in ionic currents, and modifications of Ca(2+ handling system. Simulations describe the dynamics of major signaling molecules, such as cyclic AMP and protein kinase A, in different subcellular compartments; the effects of inhibition of phosphodiesterases on cAMP production; kinetics and magnitudes of phosphorylation of ion channels, transporters, and Ca(2+ handling proteins; modifications of action potential shape and duration; magnitudes and relaxation rates of [Ca(2+]i transients; changes in intracellular and transmembrane Ca(2+ fluxes; and [Na(+]i fluxes and dynamics. The model elucidates complex interactions of ionic currents upon activation of β1-adrenoceptors at different stimulation frequencies, which ultimately lead to a relatively modest increase in action potential duration and significant increase in [Ca(2+]i transients. In particular, the model includes two subpopulations of the L-type Ca(2+ channels, in caveolae and extracaveolae compartments, and their effects on the action potential and [Ca(2+]i transients are investigated. The presented model can be used by researchers for the interpretation of experimental data and for the developments of

  20. Sub-cellular Electrical Heterogeneity Revealed by Loose Patch Recording Reflects Differential Localization of Sarcolemmal Ion Channels in Intact Rat Hearts

    Directory of Open Access Journals (Sweden)

    Igor V. Kubasov

    2018-02-01

    Full Text Available The cardiac action potential (AP is commonly recoded as an integral signal from isolated myocytes or ensembles of myocytes (with intracellular microelectrodes and extracellular macroelectrodes, respectively. These signals, however, do not provide a direct measure of activity of ion channels and transporters located in two major compartments of a cardiac myocyte: surface sarcolemma and the T-tubule system, which differentially contribute to impulse propagation and excitation-contraction (EC coupling. In the present study we investigated electrical properties of myocytes within perfused intact rat heart employing loose patch recording with narrow-tip (2 μm diameter extracellular electrodes. Using this approach, we demonstrated two distinct types of electric signals with distinct waveforms (single peak and multi-peak AP; AP1 and AP2, respectively during intrinsic pacemaker activity. These two types of waveforms depend on the position of the electrode tip on the myocyte surface. Such heterogeneity of electrical signals was lost when electrodes of larger pipette diameter were used (5 or 10 μm, which indicates that the electric signal was assessed from a region of <5 μm. Importantly, both pharmacological and mathematical simulation based on transverse (T-tubular distribution suggested that while the AP1 and the initial peak of AP2 are predominantly attributable to the fast, inward Na+ current in myocyte's surface sarcolemma, the late components of AP2 are likely representative of currents associated with L-type Ca2+ channel and Na+/Ca2+ exchanger (NCX currents which are predominantly located in T-tubules. Thus, loose patch recording with narrow-tip pipette provides a valuable tool for studying cardiac electric activity on the subcellular level in the intact heart.

  1. Particle bombardment and subcellular protein localization analysis in the aquatic plant Egeria densa

    Directory of Open Access Journals (Sweden)

    Yasuhide Osaki

    2017-09-01

    Full Text Available Particle bombardment is a powerful and relatively easy method for transient expression of genes of interest in plant cells, especially those that are recalcitrant to other transformation methods. This method has facilitated numerous analyses of subcellular localization of fluorescent fusion protein constructs. Particle bombardment delivers genes to the first layer of plant tissue. In leaves of higher plants, epidermal cells are the first cell layer. Many studies have used the epidermal cell layer of onion bulb (Allium cepa as the experimental tissue, because these cells are relatively large. However, onion epidermal cells lack developed plastids (i.e., chloroplasts, thereby precluding subcellular localization analysis of chloroplastic proteins. In this study, we developed a protocol for particle bombardment of the aquatic plant Egeria densa, and showed that it is a useful system for subcellular localization analysis of higher plant proteins. E. densa leaflets contain only two cell layers, and cells in the adaxial layer are sufficiently large for observation. The cells in both layers contain well-developed chloroplasts. We fused fluorescent proteins to conventional plant localization signals for the nucleus, cytosol, mitochondria, peroxisome, and chloroplast, and used particle bombardment to transiently express these fusion constructs in E. densa leaves. The plant subcellular localization signals functioned normally and displayed the expected distributions in transiently transformed E. densa cells, and even chloroplastic structures could be clearly visualized.

  2. Functional analysis of Plasmodium vivax VIR proteins reveals different subcellular localizations and cytoadherence to the ICAM-1 endothelial receptor.

    Science.gov (United States)

    Bernabeu, M; Lopez, F J; Ferrer, M; Martin-Jaular, L; Razaname, A; Corradin, G; Maier, A G; Del Portillo, H A; Fernandez-Becerra, C

    2012-03-01

    The subcellular localization and function of variant subtelomeric multigene families in Plasmodium vivax remain vastly unknown. Among them, the vir superfamily is putatively involved in antigenic variation and in mediating adherence to endothelial receptors. In the absence of a continuous in vitro culture system for P. vivax, we have generated P. falciparum transgenic lines expressing VIR proteins to infer location and function. We chose three proteins pertaining to subfamilies A (VIR17), C (VIR14) and D (VIR10), with domains and secondary structures that predictably traffic these proteins to different subcellular compartments. Here, we showed that VIR17 remained inside the parasite and around merozoites, whereas VIR14 and VIR10 were exported to the membrane of infected red blood cells (iRBCs) in an apparent independent pathway of Maurer's clefts. Remarkably, VIR14 was exposed at the surface of iRBCs and mediated adherence to different endothelial receptors expressed in CHO cells under static conditions. Under physiological flow conditions, however, cytoadherence was only observed to ICAM-1, which was the only receptor whose adherence was specifically and significantly inhibited by antibodies against conserved motifs of VIR proteins. Immunofluorescence studies using these antibodies also showed different subcellular localizations of VIR proteins in P. vivax-infected reticulocytes from natural infections. These data suggest that VIR proteins are trafficked to different cellular compartments and functionally demonstrates that VIR proteins can specifically mediate cytoadherence to the ICAM-1 endothelial receptor. © 2011 Blackwell Publishing Ltd.

  3. Alternative splicing and differential subcellular localization of the rat FGF antisense gene product

    Directory of Open Access Journals (Sweden)

    Casson Alan G

    2008-01-01

    Full Text Available Abstract Background GFG/NUDT is a nudix hydrolase originally identified as the product of the fibroblast growth factor-2 antisense (FGF-AS gene. While the FGF-AS RNA has been implicated as an antisense regulator of FGF-2 expression, the expression and function of the encoded GFG protein is largely unknown. Alternative splicing of the primary FGF-AS mRNA transcript predicts multiple GFG isoforms in many species including rat. In the present study we focused on elucidating the expression and subcellular distribution of alternatively spliced rat GFG isoforms. Results RT-PCR and immunohistochemistry revealed tissue-specific GFG mRNA isoform expression and subcellular distribution of GFG immunoreactivity in cytoplasm and nuclei of a wide range of normal rat tissues. FGF-2 and GFG immunoreactivity were co-localized in some, but not all, tissues examined. Computational analysis identified a mitochondrial targeting sequence (MTS in the N-terminus of three previously described rGFG isoforms. Confocal laser scanning microscopy and subcellular fractionation analysis revealed that all rGFG isoforms bearing the MTS were specifically targeted to mitochondria whereas isoforms and deletion mutants lacking the MTS were localized in the cytoplasm and nucleus. Mutation and deletion analysis confirmed that the predicted MTS was necessary and sufficient for mitochondrial compartmentalization. Conclusion Previous findings strongly support a role for the FGF antisense RNA as a regulator of FGF2 expression. The present study demonstrates that the antisense RNA itself is translated, and that protein isoforms resulting form alternative RNA splicing are sorted to different subcellular compartments. FGF-2 and its antisense protein are co-expressed in many tissues and in some cases in the same cells. The strong conservation of sequence and genomic organization across animal species suggests important functional significance to the physical association of these transcript

  4. Comparative study of human mitochondrial proteome reveals extensive protein subcellular relocalization after gene duplications

    Directory of Open Access Journals (Sweden)

    Huang Yong

    2009-11-01

    Full Text Available Abstract Background Gene and genome duplication is the principle creative force in evolution. Recently, protein subcellular relocalization, or neolocalization was proposed as one of the mechanisms responsible for the retention of duplicated genes. This hypothesis received support from the analysis of yeast genomes, but has not been tested thoroughly on animal genomes. In order to evaluate the importance of subcellular relocalizations for retention of duplicated genes in animal genomes, we systematically analyzed nuclear encoded mitochondrial proteins in the human genome by reconstructing phylogenies of mitochondrial multigene families. Results The 456 human mitochondrial proteins selected for this study were clustered into 305 gene families including 92 multigene families. Among the multigene families, 59 (64% consisted of both mitochondrial and cytosolic (non-mitochondrial proteins (mt-cy families while the remaining 33 (36% were composed of mitochondrial proteins (mt-mt families. Phylogenetic analyses of mt-cy families revealed three different scenarios of their neolocalization following gene duplication: 1 relocalization from mitochondria to cytosol, 2 from cytosol to mitochondria and 3 multiple subcellular relocalizations. The neolocalizations were most commonly enabled by the gain or loss of N-terminal mitochondrial targeting signals. The majority of detected subcellular relocalization events occurred early in animal evolution, preceding the evolution of tetrapods. Mt-mt protein families showed a somewhat different pattern, where gene duplication occurred more evenly in time. However, for both types of protein families, most duplication events appear to roughly coincide with two rounds of genome duplications early in vertebrate evolution. Finally, we evaluated the effects of inaccurate and incomplete annotation of mitochondrial proteins and found that our conclusion of the importance of subcellular relocalization after gene duplication on

  5. Multitask learning for protein subcellular location prediction.

    Science.gov (United States)

    Xu, Qian; Pan, Sinno Jialin; Xue, Hannah Hong; Yang, Qiang

    2011-01-01

    Protein subcellular localization is concerned with predicting the location of a protein within a cell using computational methods. The location information can indicate key functionalities of proteins. Thus, accurate prediction of subcellular localizations of proteins can help the prediction of protein functions and genome annotations, as well as the identification of drug targets. Machine learning methods such as Support Vector Machines (SVMs) have been used in the past for the problem of protein subcellular localization, but have been shown to suffer from a lack of annotated training data in each species under study. To overcome this data sparsity problem, we observe that because some of the organisms may be related to each other, there may be some commonalities across different organisms that can be discovered and used to help boost the data in each localization task. In this paper, we formulate protein subcellular localization problem as one of multitask learning across different organisms. We adapt and compare two specializations of the multitask learning algorithms on 20 different organisms. Our experimental results show that multitask learning performs much better than the traditional single-task methods. Among the different multitask learning methods, we found that the multitask kernels and supertype kernels under multitask learning that share parameters perform slightly better than multitask learning by sharing latent features. The most significant improvement in terms of localization accuracy is about 25 percent. We find that if the organisms are very different or are remotely related from a biological point of view, then jointly training the multiple models cannot lead to significant improvement. However, if they are closely related biologically, the multitask learning can do much better than individual learning.

  6. Vacuoles in mammals: a subcellular structure indispensable for early embryogenesis.

    Science.gov (United States)

    Wada, Yoh

    2013-01-01

    A vacuole is a membrane-bound subcellular structure involved in intracellular digestion. Instead of the large "vacuolar" organelles that are found in plants and fungi, animal cells possess lysosomes that are smaller in size and are enriched with hydrolytic enzymes similar to those found in the vacuoles. Large vacuolar structures are often observed in highly differentiated mammalian tissues such as embryonic visceral endoderm and absorbing epithelium. Vacuoles/lysosomes share a conserved mechanism of biogenesis, and they are at the terminal of the endocytic pathways, Recent genetic studies of the mammalian orthologs of Vam/Vps genes, which have essential functions for vacuole assembly, revealed that the dynamics of vacuoles/lysosomes are important for tissue differentiation and patterning through regulation of various molecular signaling events in mammals.

  7. Acute compartment syndrome in haemophilia.

    Science.gov (United States)

    Rodriguez-Merchan, E Carlos

    2013-10-01

    Acute compartment syndrome (ACS) is characterized by an increase in pressure (intramuscular pressure) within a muscle compartment, which reduces capillary perfusion threatening tissue survival. Persistence of this increased pressure for a few hours will result in necrosis of muscle and nerve tissue, with contracture in the affected limb and permanent loss of function. For that reason, early treatment and diagnosis of ACS is fundamental. Diagnosis should be based on physical examination (pain on stretching the involved muscles) and on an objective measurement of the limb perfusion pressure (DBP minus intramuscular pressure) within the affected compartment. To obtain a reliable clinical diagnosis, the patient must be evaluated every 1-2  h. In children and in unconscious patients, where the level of pain cannot be appropriately determined, an accurate clinical diagnosis is unfeasible, hence the importance of measuring compartment pressure. A fasciotomy should be performed when the limb perfusion pressure is less than 30  mmHg when averaged over a 12-h period (monitored every 1-2  h). Only 16 studies have been published on haemophilic patients with ACS, which report on a total of 34 cases. If symptoms or pressure measurements are suggestive of ACS, an extensive fasciotomy will be required. Unfortunately, fasciotomy is not exempt from complications such as the need of subsequent surgery because of a delay in wound healing, the need of a skin graft, pain, cosmetic problems, nerve injury, permanent muscle weakness and chronic venous insufficiency. Overlooked compartment syndrome remains one of most common causes of malpractice lawsuits. In haemophilia, adequate substitution of coagulation factor must be the first step. The main principle of surgical treatment is an extensive fasciotomy.

  8. Biosynthesis of the Escherichia coli K1 group 2 polysialic acid capsule occurs within a protected cytoplasmic compartment.

    Science.gov (United States)

    Steenbergen, Susan M; Vimr, Eric R

    2008-06-01

    Capsular polysaccharides are important virulence determinants in a wide range of invasive infectious diseases. Although capsule synthesis has been extensively investigated, understanding polysaccharide export from the cytoplasm to the external environment has been more difficult. Here we present the results of a novel protection assay indicating that synthesis and export of the Escherichia coli K1 group 2 capsular polysialic acid (K1 antigen) occur within a protected subcellular compartment designated the sialisome. In addition to the polymerase encoded by neuS, localization and complementation analyses indicated that the sialisome includes the accessory membrane protein NeuE. The requirement for NeuE was suppressed by overproducing NeuS, suggesting that NeuE functions by stabilizing the polymerase or facilitating its assembly in the sialisome. Although an interaction between NeuE and NeuS could not be demonstrated with a bacterial two-hybrid system that reconstitutes an intracellular cell-signalling pathway, interactions between NeuS and KpsC as well as other sialisome components were detected. The combined results provide direct evidence for specific protein-protein interactions in the synthesis and export of group 2 capsular polysaccharides under in vivo conditions. The approaches developed here will facilitate further dissection of the sialisome, suggesting similar methodology for understanding the biosynthesis of other group 2 capsules.

  9. Sustained exposure to catecholamines affects cAMP/PKA compartmentalised signalling in adult rat ventricular myocytes.

    Science.gov (United States)

    Fields, Laura A; Koschinski, Andreas; Zaccolo, Manuela

    2016-07-01

    In the heart compartmentalisation of cAMP/protein kinase A (PKA) signalling is necessary to achieve a specific functional outcome in response to different hormonal stimuli. Chronic exposure to catecholamines is known to be detrimental to the heart and disrupted compartmentalisation of cAMP signalling has been associated to heart disease. However, in most cases it remains unclear whether altered local cAMP signalling is an adaptive response, a consequence of the disease or whether it contributes to the pathogenetic process. We have previously demonstrated that isoforms of PKA expressed in cardiac myocytes, PKA-I and PKA-II, localise to different subcellular compartments and are selectively activated by spatially confined pools of cAMP, resulting in phosphorylation of distinct downstream targets. Here we investigate cAMP signalling in an in vitro model of hypertrophy in primary adult rat ventricular myocytes. By using a real time imaging approach and targeted reporters we find that that sustained exposure to catecholamines can directly affect cAMP/PKA compartmentalisation. This appears to involve a complex mechanism including both changes in the subcellular localisation of individual phosphodiesterase (PDE) isoforms as well as the relocalisation of PKA isoforms. As a result, the preferential coupling of PKA subsets with different PDEs is altered resulting in a significant difference in the level of cAMP the kinase is exposed to, with potential impact on phosphorylation of downstream targets. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  10. A Computational Modeling and Simulation Approach to Investigate Mechanisms of Subcellular cAMP Compartmentation.

    Directory of Open Access Journals (Sweden)

    Pei-Chi Yang

    2016-07-01

    Full Text Available Subcellular compartmentation of the ubiquitous second messenger cAMP has been widely proposed as a mechanism to explain unique receptor-dependent functional responses. How exactly compartmentation is achieved, however, has remained a mystery for more than 40 years. In this study, we developed computational and mathematical models to represent a subcellular sarcomeric space in a cardiac myocyte with varying detail. We then used these models to predict the contributions of various mechanisms that establish subcellular cAMP microdomains. We used the models to test the hypothesis that phosphodiesterases act as functional barriers to diffusion, creating discrete cAMP signaling domains. We also used the models to predict the effect of a range of experimentally measured diffusion rates on cAMP compartmentation. Finally, we modeled the anatomical structures in a cardiac myocyte diad, to predict the effects of anatomical diffusion barriers on cAMP compartmentation. When we incorporated experimentally informed model parameters to reconstruct an in silico subcellular sarcomeric space with spatially distinct cAMP production sites linked to caveloar domains, the models predict that under realistic conditions phosphodiesterases alone were insufficient to generate significant cAMP gradients. This prediction persisted even when combined with slow cAMP diffusion. When we additionally considered the effects of anatomic barriers to diffusion that are expected in the cardiac myocyte dyadic space, cAMP compartmentation did occur, but only when diffusion was slow. Our model simulations suggest that additional mechanisms likely contribute to cAMP gradients occurring in submicroscopic domains. The difference between the physiological and pathological effects resulting from the production of cAMP may be a function of appropriate compartmentation of cAMP signaling. Therefore, understanding the contribution of factors that are responsible for coordinating the spatial and

  11. Compartment-Specific Importance of Ascorbate During Environmental Stress in Plants.

    Science.gov (United States)

    Zechmann, Bernd

    2017-08-10

    Ascorbate is an essential antioxidant in plants. Total contents and its redox state in organelles are crucial to fight and signal oxidative stress. Recent Advances: With quantitative immunoelectron microscopy and biochemical methods, highest ascorbate contents have recently been measured in peroxisomes (23 mM) and the cytosol (22 mM), lowest ones in vacuoles (2 mM), and intermediate concentrations (4-16 mM) in all other organelles. The accumulation of ascorbate in chloroplasts and peroxisomes is crucial for plant defense. Its depletion in chloroplasts, peroxisomes, and mitochondria during biotic stress leads to the accumulation of reactive oxygen species (ROS) and the development of chlorosis and necrosis. In the apoplast and vacuoles, ascorbate is the most important antioxidant for the detoxification of ROS. The cytosol acts as a hub for ascorbate metabolism as it reduces its oxidized forms that are produced in the cytosol or imported from other cell compartments. It is a sink for ascorbate that is produced in mitochondria, distributes ascorbate to all organelles, and uses ascorbate to detoxify ROS. As ascorbate and its redox state are involved in protein synthesis and modifications, it can be concluded that ascorbate in the cytosol senses oxidative stress and regulates plant growth, development, and defense. Future research should focus on (1) dissecting roles of ascorbate in vacuoles and the lumen of the endoplasmic reticulum, (2) identifying the physiological relevance of ascorbate transporters, and (3) correlating current data with changes in the subcellular distribution of related enzymes, ROS, and gene expression patterns.

  12. Mapping the subcellular localization of Fe3O4@TiO2 nanoparticles by X-ray Fluorescence Microscopy

    Science.gov (United States)

    Yuan, Y.; Chen, S.; Gleber, S. C.; Lai, B.; Brister, K.; Flachenecker, C.; Wanzer, B.; Paunesku, T.; Vogt, S.; Woloschak, G. E.

    2013-10-01

    The targeted delivery of Fe3O4@TiO2 nanoparticles to cancer cells is an important step in their development as nanomedicines. We have synthesized nanoparticles that can bind the Epidermal Growth Factor Receptor, a cell surface protein that is overexpressed in many epithelial type cancers. In order to study the subcellular distribution of these nanoparticles, we have utilized the sub-micron resolution of X-ray Fluorescence Microscopy to map the location of Fe3O4@TiO2 NPs and other trace metal elements within HeLa cervical cancer cells. Here we demonstrate how the higher resolution of the newly installed Bionanoprobe at the Advanced Photon Source at Argonne National Laboratory can greatly improve our ability to distinguish intracellular nanoparticles and their spatial relationship with subcellular compartments.

  13. Subcellular sorting of the G-protein coupled mouse somatostatin receptor 5 by a network of PDZ-domain containing proteins.

    Directory of Open Access Journals (Sweden)

    Carola Bauch

    Full Text Available PSD-95/discs large/ZO-1 (PDZ domain proteins integrate many G-protein coupled receptors (GPCRs into membrane associated signalling complexes. Additional PDZ proteins are involved in intracellular receptor trafficking. We show that three PDZ proteins (SNX27, PIST and NHERF1/3 regulate the mouse somatostatin receptor subtype 5 (SSTR5. Whereas the PDZ ligand motif of SSTR5 is not necessary for plasma membrane targeting or internalization, it protects the SSTR5 from postendocytic degradation. Under conditions of lysosomal inhibition, recycling of the SSTR5 to the plasma membrane does not depend on the PDZ ligand. However, recycling of the wild type receptor carrying the PDZ binding motif depends on SNX27 which interacts and colocalizes with the receptor in endosomal compartments. PIST, implicated in lysosomal targeting of some membrane proteins, does not lead to degradation of the SSTR5. Instead, overexpressed PIST retains the SSTR5 at the Golgi. NHERF family members release SSTR5 from retention by PIST, allowing for plasma membrane insertion. Our data suggest that PDZ proteins act sequentially on the GPCR at different stages of its subcellular trafficking.

  14. The phosphoarginine energy-buffering system of trypanosoma brucei involves multiple arginine kinase isoforms with different subcellular locations.

    Directory of Open Access Journals (Sweden)

    Frank Voncken

    Full Text Available Phosphagen energy-buffering systems play an essential role in regulating the cellular energy homeostasis in periods of high-energy demand or energy supply fluctuations. Here we describe the phosphoarginine/arginine kinase system of the kinetoplastid parasite Trypanosoma brucei, consisting of three highly similar arginine kinase isoforms (TbAK1-3. Immunofluorescence microscopy using myc-tagged protein versions revealed that each isoform is located in a specific subcellular compartment: TbAK1 is exclusively found in the flagellum, TbAK2 in the glycosome, and TbAK3 in the cytosol of T. brucei. The flagellar location of TbAK1 is dependent on a 22 amino acid long N-terminal sequence, which is sufficient for targeting a GFP-fusion protein to the trypanosome flagellum. The glycosomal location of TbAK2 is in agreement with the presence of a conserved peroxisomal targeting signal, the C-terminal tripeptide 'SNL'. TbAK3 lacks any apparent targeting sequences and is accordingly located in the cytosol of the parasite. Northern blot analysis indicated that each TbAK isoform is differentially expressed in bloodstream and procyclic forms of T. brucei, while the total cellular arginine kinase activity was 3-fold higher in bloodstream form trypanosomes. These results suggest a substantial change in the temporal and spatial energy requirements during parasite differentiation. Increased arginine kinase activity improved growth of procyclic form T. brucei during oxidative challenges with hydrogen peroxide. Elimination of the total cellular arginine kinase activity by RNA interference significantly decreased growth (>90% of procyclic form T. brucei under standard culture conditions and was lethal for this life cycle stage in the presence of hydrogen peroxide. The putative physiological roles of the different TbAK isoforms in T. brucei are further discussed.

  15. The Phosphoarginine Energy-Buffering System of Trypanosoma brucei Involves Multiple Arginine Kinase Isoforms with Different Subcellular Locations

    Science.gov (United States)

    Wadforth, Cath; Harley, Maggie; Colasante, Claudia

    2013-01-01

    Phosphagen energy-buffering systems play an essential role in regulating the cellular energy homeostasis in periods of high-energy demand or energy supply fluctuations. Here we describe the phosphoarginine/arginine kinase system of the kinetoplastid parasite Trypanosoma brucei, consisting of three highly similar arginine kinase isoforms (TbAK1-3). Immunofluorescence microscopy using myc-tagged protein versions revealed that each isoform is located in a specific subcellular compartment: TbAK1 is exclusively found in the flagellum, TbAK2 in the glycosome, and TbAK3 in the cytosol of T. brucei. The flagellar location of TbAK1 is dependent on a 22 amino acid long N-terminal sequence, which is sufficient for targeting a GFP-fusion protein to the trypanosome flagellum. The glycosomal location of TbAK2 is in agreement with the presence of a conserved peroxisomal targeting signal, the C-terminal tripeptide ‘SNL’. TbAK3 lacks any apparent targeting sequences and is accordingly located in the cytosol of the parasite. Northern blot analysis indicated that each TbAK isoform is differentially expressed in bloodstream and procyclic forms of T. brucei, while the total cellular arginine kinase activity was 3-fold higher in bloodstream form trypanosomes. These results suggest a substantial change in the temporal and spatial energy requirements during parasite differentiation. Increased arginine kinase activity improved growth of procyclic form T. brucei during oxidative challenges with hydrogen peroxide. Elimination of the total cellular arginine kinase activity by RNA interference significantly decreased growth (>90%) of procyclic form T. brucei under standard culture conditions and was lethal for this life cycle stage in the presence of hydrogen peroxide. The putative physiological roles of the different TbAK isoforms in T. brucei are further discussed. PMID:23776565

  16. Compartment syndrome in a neonate

    Directory of Open Access Journals (Sweden)

    Magdalena Santosa

    2006-10-01

    Full Text Available A neonate born with severe asphyxia and considerable risk of infection was treated with intravenous sodium bicarbonate and intravenous antibiotics. At the age of five days he developed edema of the right forearm, tense on palpation, painful, hyperemic, and the hand was pallor, hypesthetic with maceration of the fifth finger. The diagnosis of compartment syndrome was established but it was delayed at least for about 48 hours. Decompression by fasciotomy using the volar Henry approach was performed; after which the pathologic changes rapidly subsided.  The cause of this syndrome wasprobably due to intravenous sodium bicarbonate and repeated intravenous antibiotics. From this experience it is strongly emphasized that we have to be aware and able to diagnose compartment syndrome at the earliest possible time in severely ill neonates and children who have multiple intravenous injection. Daily inspection and careful evaluation of the condition at the site of the intravenous line will be very crucial to detect the syndrome.

  17. Pressure management in compartment fires

    OpenAIRE

    Hostikka, Simo; Kallada Janardhan, Rahul

    2017-01-01

    Fire-induced pressure has not been considered a threat for structural or occupant safety in apartment fires. The situation may be changing as the building envelopes are becoming much more air-tight due to the energy efficiency requirements and the construction of high-rise buildings. In this project, we investigated the effects of the building's air-tightness, ventilation configuration and the fire growth rate on the peak overpressures inside the fire compartment and smoke spread within the m...

  18. Membrane order in the plasma membrane and endocytic recycling compartment.

    Science.gov (United States)

    Iaea, David B; Maxfield, Frederick R

    2017-01-01

    The cholesterol content of membranes plays an important role in organizing membranes for signal transduction and protein trafficking as well as in modulating the biophysical properties of membranes. While the properties of model or isolated membranes have been extensively studied, there has been little evaluation of internal membranes in living cells. Here, we use a Nile Red based probe, NR12S, and ratiometric live cell imaging, to analyze the membrane order of the plasma membrane and endocytic recycling compartment. We find that after a brief incubation to allow endocytosis, NR12S is distributed between the plasma membrane and the endocytic recycling compartment. The NR12S reports that the endocytic recycling compartment is more highly ordered than the plasma membrane. We also find that the plasma membrane and the endocytic recycling compartment are differentially affected by altering cellular cholesterol levels. The membrane order of the plasma membrane, but not the endocytic recycling compartment, is altered significantly when cellular cholesterol content is increased or decreased by 20%. These results demonstrate that changes in cellular cholesterol differentially alter membrane order within different organelles.

  19. Subcellular targeting domains of sphingomyelin synthase 1 and 2.

    Science.gov (United States)

    Yeang, Calvin; Ding, Tingbo; Chirico, William J; Jiang, Xian-Cheng

    2011-12-14

    Sphingomyelin synthase (SMS) sits at the crossroads of sphingomyelin (SM), ceramide, diacylglycerol (DAG) metabolism. It utilizes ceramide and phosphatidylcholine as substrates to produce SM and DAG, thereby regulating lipid messengers which play a role in cell survival and apoptosis. Furthermore, its product SM has been implicated in atherogenic processes such as retention of lipoproteins in the blood vessel intima. There are two mammalian sphingomyelin synthases: SMS1 and SMS2. SMS1 is found exclusively in the Golgi at steady state, whereas SMS2 exists in the Golgi and plasma membrane. Conventional motifs responsible for protein targeting to the plasma membrane or Golgi are either not present in, or unique to, SMS1 and SMS2. In this study, we examined how SMS1 and SMS2 achieve their respective subcellular localization patterns. Brefeldin A treatment prevented SMS1 and SMS2 from exiting the ER, demonstrating that they transit through the classical secretory pathway. We created truncations and chimeras of SMS1 and SMS2 to define their targeting signals. We found that SMS1 contains a C-terminal Golgi targeting signal and that SMS2 contains a C-terminal plasma membrane targeting signal.

  20. Abdominal Compartment Syndrome due to OHSS

    OpenAIRE

    Firoozeh Veisi; Maryam Zangeneh; Shohreh Malekkhosravi; Negin Rezavand

    2012-01-01

    Abdominal compartment syndrome is a dangerous clinical situation, usually following abdominal injuries&operations. It is seldom observed in patients with gynecologic and obstetric problems. Abdominalcompartment syndrome may be consequence ovarian hyperstimulation syndrome. A 28-year-old womanpresented as a sever ovarian hyperstimulation.The increased IAP indicated that OHSS may beconsidered a compartment syndrome. Abdominal compartment syndrome needs laparotomy orparacentesis for reductio...

  1. 36 CFR 1192.127 - Sleeping compartments.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Sleeping compartments. 1192.127 Section 1192.127 Parks, Forests, and Public Property ARCHITECTURAL AND TRANSPORTATION BARRIERS... Intercity Rail Cars and Systems § 1192.127 Sleeping compartments. (a) Sleeping compartments required to be...

  2. 24 CFR 3280.111 - Toilet compartments.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Toilet compartments. 3280.111... Toilet compartments. Each toilet compartment shall be a minimum of 30 inches in width, except, when the toilet is located adjacent to the short dimension of the tub, the distance from the tub to the center...

  3. A critical role for endocytosis in Wnt signaling

    Directory of Open Access Journals (Sweden)

    Nusse Roel

    2006-07-01

    Full Text Available Abstract Background The Wnt signaling pathway regulates many processes during embryonic development, including axis specification, organogenesis, angiogenesis, and stem cell proliferation. Wnt signaling has also been implicated in a number of cancers, bone density maintenance, and neurological conditions during adulthood. While numerous Wnts, their cognate receptors of the Frizzled and Arrow/LRP5/6 families and downstream pathway components have been identified, little is known about the initial events occurring directly after receptor activation. Results We show here that Wnt proteins are rapidly endocytosed by a clathrin- and dynamin-mediated process. While endocytosis has traditionally been considered a principal mechanism for receptor down-regulation and termination of signaling pathways, we demonstrate that interfering with clathrin-mediated endocytosis actually blocks Wnt signaling at the level of β-catenin accumulation and target gene expression. Conclusion A necessary component of Wnt signaling occurs in a subcellular compartment distinct from the plasma membrane. Moreover, as internalized Wnts transit partially through the transferrin recycling pathway, it is possible that a "signaling endosome" serves as a nexus for activated Wnt pathway components.

  4. Heme Gazing: Illuminating Eukaryotic Heme Trafficking, Dynamics, and Signaling with Fluorescent Heme Sensors.

    Science.gov (United States)

    Hanna, David A; Martinez-Guzman, Osiris; Reddi, Amit R

    2017-04-04

    Heme (iron protoporphyrin IX) is an essential protein prosthetic group and signaling molecule required for most life on Earth. All heme-dependent processes require the dynamic and rapid mobilization of heme from sites of synthesis or uptake to hemoproteins present in virtually every subcellular compartment. The cytotoxicity and hydrophobicity of heme necessitate that heme mobilization be carefully controlled to mitigate the deleterious effects of this essential toxin. Indeed, a number of disorders, including certain cancers, cardiovascular diseases, and aging and age-related neurodegenerative diseases, are tied to defects in heme homeostasis. However, the molecules and mechanisms that mediate heme transport and trafficking, and the dynamics of these processes, are poorly understood. This is in large part due to the lack of physical tools for probing cellular heme. Herein, we discuss the recent development of fluorescent probes that can monitor and image kinetically labile heme with respect to its mobilization and role in signaling. In particular, we will highlight how heme gazing with these tools can uncover new heme trafficking factors upon being integrated with genetic screens and illuminate the concentration, subcellular distribution, and dynamics of labile heme in various physiological contexts. Altogether, the monitoring of labile heme, along with recent biochemical and cell biological studies demonstrating the reversible regulation of certain cellular processes by heme, is challenging us to reconceptualize heme from being a static cofactor buried in protein active sites to a dynamic and mobile signaling molecule.

  5. Acute Compartment Syndrome of the Leg.

    Science.gov (United States)

    Konda, Sanjit R; Kester, Benjamin S; Fisher, Nina; Behery, Omar A; Crespo, Alexander M; Egol, Kenneth A

    2017-08-01

    Acute compartment syndrome (ACS) is well known among orthopaedic surgeons. The timely diagnosis and management of ACS is crucial to avoiding its sequelae, including renal failure, ischemic contractures, and limb loss. Despite its relative importance, ACS poses a challenge to many residents and clinicians as diagnosis relies largely on clinical judgment. Timely diagnosis and thorough compartment release are essential to optimizing outcomes in ACS. This video highlights a clinical case in which compartment syndrome of the leg was considered, diagnosed, and surgically managed. This video will present the indications for compartment release and a video-guided demonstration of compartment checks using an arterial line transducer, a 4-compartment fasciotomy with 2 incisions, and temporizing vessel loop closure. Compartment syndrome can be a devastating complication of common fractures. It is essential that orthopaedic practitioners understand the immediacy of intervention. We have a responsibility to provide timely, accurate diagnosis along with expedient surgical management.

  6. Assessing the precision of high-throughput computational and laboratory approaches for the genome-wide identification of protein subcellular localization in bacteria

    Directory of Open Access Journals (Sweden)

    Brinkman Fiona SL

    2005-11-01

    Full Text Available Abstract Background Identification of a bacterial protein's subcellular localization (SCL is important for genome annotation, function prediction and drug or vaccine target identification. Subcellular fractionation techniques combined with recent proteomics technology permits the identification of large numbers of proteins from distinct bacterial compartments. However, the fractionation of a complex structure like the cell into several subcellular compartments is not a trivial task. Contamination from other compartments may occur, and some proteins may reside in multiple localizations. New computational methods have been reported over the past few years that now permit much more accurate, genome-wide analysis of the SCL of protein sequences deduced from genomes. There is a need to compare such computational methods with laboratory proteomics approaches to identify the most effective current approach for genome-wide localization characterization and annotation. Results In this study, ten subcellular proteome analyses of bacterial compartments were reviewed. PSORTb version 2.0 was used to computationally predict the localization of proteins reported in these publications, and these computational predictions were then compared to the localizations determined by the proteomics study. By using a combined approach, we were able to identify a number of contaminants and proteins with dual localizations, and were able to more accurately identify membrane subproteomes. Our results allowed us to estimate the precision level of laboratory subproteome studies and we show here that, on average, recent high-precision computational methods such as PSORTb now have a lower error rate than laboratory methods. Conclusion We have performed the first focused comparison of genome-wide proteomic and computational methods for subcellular localization identification, and show that computational methods have now attained a level of precision that is exceeding that of high

  7. The subcellular distribution of the human ribosomal "stalk" components: P1, P2 and P0 proteins

    DEFF Research Database (Denmark)

    Tchórzewski, Marek; Krokowski, Dawid; Rzeski, Wojciech

    2003-01-01

    to the ribosome through the P0 protein. The "stalk" is essential for the ribosome activity, taking part in the interaction with elongation factors.In this report, we have shown that the subcellular distribution of the human P proteins does not fall into standard behavior of regular ribosomal proteins. We have...... used two approaches to assess the distribution of the P proteins, in vivo experiments with GFP fusion proteins and in vitro one with anti-P protein antibodies. In contrast to standard r-proteins, the P1 and P2 proteins are not actively transported into the nucleus compartment, remaining predominantly...... in the cytoplasm (the perinuclear compartment). The P0 protein was found in the cytoplasm, as well as in the nucleus; however, the nucleoli were excluded. This protein was scattered around the nuclei, and the distribution might reflect association with the so-called nuclear bodies. This is the first example of r...

  8. Evolution and comparative genomics of subcellular specializations: EST sequencing of Torpedo electric organ.

    Science.gov (United States)

    Nazarian, Javad; Berry, Deborah L; Sanjari, Salar; Razvi, Mohammed; Brown, Kristy; Hathout, Yetrib; Vertes, Akos; Dadgar, Sherry; Hoffman, Eric P

    2011-03-01

    Uncharacterized open reading frames (ORFs) in human genomic sequence often show a high degree of evolutionary conservation, yet have little or no tissue EST or protein data suggestive of protein product function. The encoded proteins may have highly restricted expression in specialized cells, subcellular specializations, and/or narrow windows during development. One such highly specialized and minute subcellular compartment is the neuromuscular junction (NMJ), where motorneurons contact muscle fibers. The electric Torpedo ray has evolved to expand the NMJ structure to the size of a large organ (electroplax organ), and we hypothesized that Torpedo electroplax proteins would be candidates for human ESTs expressed at the human NMJ. A total of 9719 primary electroplax cDNA clones were sequenced. We identified 44 human ORFs showing high (>63%) amino acid identity to Torpedo electroplax transcripts with enrichment for mRNA splicing motifs (SH2 and pre-mRNA splicing domains), an observation potentially important for the strict nuclear domains maintained by myonuclei underlying the NMJ. We generated antibodies against two uncharacterized human genes (C19orf29 [Drosophila cactin] and C15orf24) and showed that these were indeed expressed at the murine NMJ. Cactin, a member of the Rel transcription factor family in Drosophila, localized to the postsynaptic cytosol of the NMJ and nuclear membrane. C15orf24 protein localized to the murine postsynaptic sarcolemma. We show a novel approach towards identifying proteins expressed at a subcellular specialization using evolutionary diversity of organ function and cross-species mapping. Copyright © 2010 Elsevier B.V. All rights reserved.

  9. Prediction of essential proteins based on subcellular localization and gene expression correlation.

    Science.gov (United States)

    Fan, Yetian; Tang, Xiwei; Hu, Xiaohua; Wu, Wei; Ping, Qing

    2017-12-01

    Essential proteins are indispensable to the survival and development process of living organisms. To understand the functional mechanisms of essential proteins, which can be applied to the analysis of disease and design of drugs, it is important to identify essential proteins from a set of proteins first. As traditional experimental methods designed to test out essential proteins are usually expensive and laborious, computational methods, which utilize biological and topological features of proteins, have attracted more attention in recent years. Protein-protein interaction networks, together with other biological data, have been explored to improve the performance of essential protein prediction. The proposed method SCP is evaluated on Saccharomyces cerevisiae datasets and compared with five other methods. The results show that our method SCP outperforms the other five methods in terms of accuracy of essential protein prediction. In this paper, we propose a novel algorithm named SCP, which combines the ranking by a modified PageRank algorithm based on subcellular compartments information, with the ranking by Pearson correlation coefficient (PCC) calculated from gene expression data. Experiments show that subcellular localization information is promising in boosting essential protein prediction.

  10. Improving drug potency and efficacy by nanocarrier-mediated subcellular targeting.

    Science.gov (United States)

    Murakami, Mami; Cabral, Horacio; Matsumoto, Yu; Wu, Shourong; Kano, Mitsunobu R; Yamori, Takao; Nishiyama, Nobuhiro; Kataoka, Kazunori

    2011-01-05

    Nanocarrier-mediated drug targeting is an emerging strategy for cancer therapy and is being used, for example, with chemotherapeutic agents for ovarian cancer. Nanocarriers are selectively accumulated in tumors as a result of their enhanced permeability and retention of macromolecules, thereby enhancing the antitumor activity of the nanocarrier-associated drugs. We investigated the real-time subcellular fate of polymeric micelles incorporating (1,2-diaminocyclohexane) platinum(II) (DACHPt/m), the parent complex of oxaliplatin, in tumor tissues by fluorescence-based assessment of their kinetic stability. These observations revealed that DACHPt/m was extravasated from blood vessels to the tumor tissue and dissociated inside each cell. Furthermore, DACHPt/m selectively dissociated within late endosomes, enhancing drug delivery to the nearby nucleus relative to free oxaliplatin, likely by circumvention of the cytoplasmic detoxification systems such as metallothionein and methionine synthase. Thus, these drug-loaded micelles exhibited higher antitumor activity than did oxaliplatin alone, even against oxaliplatin-resistant tumors. These findings suggest that nanocarriers targeting subcellular compartments may have considerable benefits in clinical applications.

  11. LOCnet and LOCtarget: sub-cellular localization for structural genomics targets

    Science.gov (United States)

    Nair, Rajesh; Rost, Burkhard

    2004-01-01

    LOCtarget is a web server and database that predicts and annotates sub-cellular localization for structural genomics targets; LOCnet is one of the methods used in LOCtarget that can predict sub-cellular localization for all eukaryotic and prokaryotic proteins. Targets are taken from the central registration database for structural genomics, namely, TargetDB. LOCtarget predicts localization through a combination of four different methods: known nuclear localization signals (PredictNLS), homology-based transfer of experimental annotations (LOChom), inference through automatic text analysis of SWISS-PROT keywords (LOCkey) and de novo prediction through a system of neural networks (LOCnet). Additionally, we report predictions from SignalP. The final prediction is based on the method with the highest confidence. The web server can be used to predict sub-cellular localization of proteins from their amino acid sequence. The LOCtarget database currently contains localization predictions for all eukaryotic proteins from TargetDB and is updated every week. The server is available at http://www.rostlab.org/services/LOCtarget/. PMID:15215440

  12. Dynamically Active Compartments Coupled by a Stochastically Gated Gap Junction

    Science.gov (United States)

    Bressloff, Paul C.; Lawley, Sean D.

    2017-10-01

    We analyze a one-dimensional PDE-ODE system representing the diffusion of signaling molecules between two cells coupled by a stochastically gated gap junction. We assume that signaling molecules diffuse within the cytoplasm of each cell and then either bind to some active region of the cell's membrane (treated as a well-mixed compartment) or pass through the gap junction to the interior of the other cell. We treat the gap junction as a randomly fluctuating gate that switches between an open and a closed state according to a two-state Markov process. This means that the resulting PDE-ODE is stochastic due to the presence of a randomly switching boundary in the interior of the domain. It is assumed that each membrane compartment acts as a conditional oscillator, that is, it sits below a supercritical Hopf bifurcation. In the ungated case (gap junction always open), the system supports diffusion-induced oscillations, in which the concentration of signaling molecules within the two compartments is either in-phase or anti-phase. The presence of a reflection symmetry (for identical cells) means that the stochastic gate only affects the existence of anti-phase oscillations. In particular, there exist parameter choices where the gated system supports oscillations, but the ungated system does not, and vice versa. The existence of oscillations is investigated by solving a spectral problem obtained by averaging over realizations of the stochastic gate.

  13. The Role of Peroxiredoxins in the Transduction of H2O2 Signals.

    Science.gov (United States)

    Rhee, Sue Goo; Woo, Hyun Ae; Kang, Dongmin

    2017-07-10

    Hydrogen peroxide (H2O2) is produced on stimulation of many cell surface receptors and serves as an intracellular messenger in the regulation of diverse physiological events, mostly by oxidizing cysteine residues of effector proteins. Mammalian cells express multiple H2O2-eliminating enzymes, including catalase, glutathione peroxidase (GPx), and peroxiredoxin (Prx). A conserved cysteine in Prx family members is the site of oxidation by H2O2. Peroxiredoxins possess a high-affinity binding site for H2O2 that is lacking in catalase and GPx and which renders the catalytic cysteine highly susceptible to oxidation, with a rate constant several orders of magnitude greater than that for oxidation of cysteine in most H2O2 effector proteins. Moreover, Prxs are abundant and present in all subcellular compartments. The cysteines of most H2O2 effectors are therefore at a competitive disadvantage for reaction with H2O2. Recent Advances: Here we review intracellular sources of H2O2 as well as H2O2 target proteins classified according to biochemical and cellular function. We then highlight two strategies implemented by cells to overcome the kinetic disadvantage of most target proteins with regard to H2O2-mediated oxidation: transient inactivation of local Prx molecules via phosphorylation, and indirect oxidation of target cysteines via oxidized Prx. Critical Issues and Future Directions: Recent studies suggest that only a small fraction of the total pools of Prxs and H2O2 effector proteins localized in specific subcellular compartments participates in H2O2 signaling. Development of sensitive tools to selectively detect phosphorylated Prxs and oxidized effector proteins is needed to provide further insight into H2O2 signaling. Antioxid. Redox Signal. 00, 000-000.

  14. Acute compartment syndrome caused by uncontrolled hypothyroidism.

    Science.gov (United States)

    Modi, Anar; Amin, Hari; Salzman, Matthew; Morgan, Farah

    2017-06-01

    Acute compartment syndrome is increased tissue pressure exceeding perfusion pressure in a closed compartment resulting in nerve and muscle ischemia. Common precipitating causes are crush injuries, burns, substance abuse, osseous or vascular limb trauma. This is a case of 42year old female with history of hypothyroidism who presented to emergency room with acute onset of severe pain and swelling in right lower extremity. Physical examination was concerning for acute compartment syndrome of right leg which was confirmed by demonstration of elevated compartmental pressures. No precipitating causes were readily identified. Further laboratory testing revealed uncontrolled hypothyroidism. Management included emergent fasciotomy and initiating thyroid hormone replacement. This case represents a rare association between acute compartment syndrome and uncontrolled hypothyroidism. We also discuss the pathogenesis of compartment syndrome in hypothyroid patients and emphasize the importance of evaluating for less common causes, particularly in setting of non-traumatic compartment syndrome. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Nanopipette-Based SERS Aptasensor for Subcellular Localization of Cancer Biomarker in Single Cells.

    Science.gov (United States)

    Hanif, Sumaira; Liu, Hai-Ling; Ahmed, Saud Asif; Yang, Jin-Mei; Zhou, Yue; Pang, Jie; Ji, Li-Na; Xia, Xing-Hua; Wang, Kang

    2017-09-19

    Single cell analysis is essential for understanding the heterogeneity, behaviors of cells, and diversity of target analyte in different subcellular regions. Nucleolin (NCL) is a multifunctional protein that is markedly overexpressed in most of the cancer cells. The variant expression levels of NCL in subcellular regions have a marked influence on cancer proliferation and treatments. However, the specificity of available methods to identify the cancer biomarkers is limited because of the high level of subcellular matrix effect. Herein, we proposed a novel technique to increase both the molecular and spectral specificity of cancer diagnosis by using aptamers affinity based portable nanopipette with distinctive surface-enhanced Raman scattering (SERS) activities. The aptamers-functionalized gold-coated nanopipette was used to capture target, while p-mercaptobenzonitrile (MBN) and complementary DNA modified Ag nanoparticles (AgNPs) worked as Raman reporter to produce SERS signal. The SERS signal of Raman nanotag was lost upon NCL capturing via modified DNA aptamers on nanoprobe, which further helped to verify the specificity of nanoprobe. For proof of concept, NCL protein was specifically extracted from different cell lines by aptamers modified SERS active nanoprobe. The nanoprobes manifested specifically good affinity for NCL with a dissociation constant Kd of 36 nM and provided a 1000-fold higher specificity against other competing proteins. Furthermore, the Raman reporter moiety has a vibrational frequency in the spectroscopically silent region (1800-2300 cm-1) with a negligible matrix effect from cell analysis. The subcellular localization and spatial distribution of NCL were successfully achieved in various types of cells, including MCF-7A, HeLa, and MCF-10A cells. This type of probing technique for single cell analysis could lead to the development of a new perspective in cancer diagnosis and treatment at the cellular level.

  16. Abdominal Compartment Syndrome due to OHSS

    Directory of Open Access Journals (Sweden)

    Firoozeh Veisi

    2012-03-01

    Full Text Available Abdominal compartment syndrome is a dangerous clinical situation, usually following abdominal injuries&operations. It is seldom observed in patients with gynecologic and obstetric problems. Abdominalcompartment syndrome may be consequence ovarian hyperstimulation syndrome. A 28-year-old womanpresented as a sever ovarian hyperstimulation.The increased IAP indicated that OHSS may beconsidered a compartment syndrome. Abdominal compartment syndrome needs laparotomy orparacentesis for reduction of pressure.

  17. Can intramuscular glucose levels diagnose compartment syndrome?

    Science.gov (United States)

    Doro, Christopher J; Sitzman, Thomas J; O'Toole, Robert V

    2014-02-01

    Compartment syndrome is difficult to diagnose, particularly in patients who are not able to undergo adequate clinical examination. Current methods rely on pressure measurements within the compartment, have high false-positive rates, and do not reliably indicate presence of muscle ischemia. We hypothesized that measurement of intramuscular glucose and oxygen can identify compartment syndrome with high sensitivity and specificity. Compartment syndrome was created in 12 anesthetized adult mixed-sex beagles, in the craniolateral compartment of a lower leg, by infusion of lactated Ringer's solution with normal serum concentration of glucose. The contralateral leg served as a control. Hydrostatic pressure, oxygen tension, and glucose concentration were recorded with commercially available probes. Compartment syndrome was maintained for 8 hours, and the animals were recovered. Two weeks later, compartment and control legs underwent muscle biopsy. Specimens were reviewed by a blinded pathologist. Within 15 minutes of creating compartment syndrome, glucose concentration and oxygen tension in the experimental limb were significantly lower than in the control limb (glucose, p = 0.02; oxygen, p = 0.007; two-tailed t test). Intramuscular glucose concentration of less than 97 mg/dL was 100% sensitive (95% confidence interval [CI], 73-100%) and 75% specific (95% CI, 40-94%) for the presence of compartment syndrome. Partial pressure of oxygen less than 30 mm Hg was 100% sensitive (95% CI, 72-100%) and 100% specific (95% CI, 69-100%) for the presence of compartment syndrome. Pathology confirmed compartment syndrome in all experimental limbs. Our results show that intramuscular glucose concentration and partial pressure of oxygen rapidly identify muscle ischemia with high sensitivity and specificity after experimentally created compartment syndrome in this animal model.

  18. Forearm Compartment Syndrome: Evaluation and Management.

    Science.gov (United States)

    Kistler, Justin M; Ilyas, Asif M; Thoder, Joseph J

    2018-02-01

    Compartment syndrome of the forearm is uncommon but can have devastating consequences. Compartment syndrome is a result of osseofascial swelling leading to decreased tissue perfusion and tissue necrosis. There are numerous causes of forearm compartment syndrome and high clinical suspicion must be maintained to avoid permanent disability. The most widely recognized symptoms include pain out of proportion and pain with passive stretch of the wrist and digits. Early diagnosis and decompressive fasciotomy are essential in the treatment of forearm compartment syndrome. Closure of fasciotomy wounds can often be accomplished by primary closure but many patients require additional forms of soft tissue coverage procedures. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. SLC30A3 (ZnT3 oligomerization by dityrosine bonds regulates its subcellular localization and metal transport capacity.

    Directory of Open Access Journals (Sweden)

    Gloria Salazar

    2009-06-01

    Full Text Available Non-covalent and covalent homo-oligomerization of membrane proteins regulates their subcellular localization and function. Here, we described a novel oligomerization mechanism affecting solute carrier family 30 member 3/zinc transporter 3 (SLC30A3/ZnT3. Oligomerization was mediated by intermolecular covalent dityrosine bonds. Using mutagenized ZnT3 expressed in PC12 cells, we identified two critical tyrosine residues necessary for dityrosine-mediated ZnT3 oligomerization. ZnT3 carrying the Y372F mutation prevented ZnT3 oligomerization, decreased ZnT3 targeting to synaptic-like microvesicles (SLMVs, and decreased resistance to zinc toxicity. Strikingly, ZnT3 harboring the Y357F mutation behaved as a "gain-of-function" mutant as it displayed increased ZnT3 oligomerization, targeting to SLMVs, and increased resistance to zinc toxicity. Single and double tyrosine ZnT3 mutants indicate that the predominant dimeric species is formed between tyrosine 357 and 372. ZnT3 tyrosine dimerization was detected under normal conditions and it was enhanced by oxidative stress. Covalent species were also detected in other SLC30A zinc transporters localized in different subcellular compartments. These results indicate that covalent tyrosine dimerization of a SLC30A family member modulates its subcellular localization and zinc transport capacity. We propose that dityrosine-dependent membrane protein oligomerization may regulate the function of diverse membrane protein in normal and disease states.

  20. Subcellular localization of an intracellular serine protease of 68 kDa in Leishmania (Leishmania amazonensis promastigotes

    Directory of Open Access Journals (Sweden)

    José Andrés Morgado-Díaz

    2005-07-01

    Full Text Available Here we report the subcellular localization of an intracellular serine protease of 68 kDa in axenic promastigotes of Leishmania (Leishmania amazonensis, using subcellular fractionation, enzymatic assays, immunoblotting, and immunocytochemistry. All fractions were evaluated by transmission electron microscopy and the serine protease activity was measured during the cell fractionation procedure using a-N-r-tosyl-L-arginine methyl ester (L-TAME as substrate, phenylmethylsulphone fluoride (PMSF and L-1-tosylamino-2-phenylethylchloromethylketone (TPCK as specific inhibitors. The enzymatic activity was detected mainly in a membranous vesicular fraction (6.5-fold enrichment relative to the whole homogenate, but also in a crude plasma membrane fraction (2.0-fold. Analysis by SDS-PAGE gelatin under reducing conditions demonstrated that the major proteolytic activity was found in a 68 kDa protein in all fractions studied. A protein with identical molecular weight was also recognized in immunoblots by a polyclonal antibody against serine protease (anti-SP, with higher immunoreactivity in the vesicular fraction. Electron microscopic immunolocalization using the same polyclonal antibody showed the enzyme present at the cell surface, as well as in cytoplasmic membranous compartments of the parasite. Our findings indicate that the internal location of this serine protease in L. amazonensis is mainly restricted to the membranes of intracellular compartments resembling endocytic/exocytic elements.

  1. The impact of subcellular location on the near infrared-mediated thermal ablation of cells by targeted carbon nanotubes

    Science.gov (United States)

    Murali, Vasanth S.; Wang, Ruhung; Mikoryak, Carole A.; Pantano, Paul; Draper, Rockford K.

    2016-10-01

    Single-walled carbon nanotubes (SWNTs) are used in the near infrared (NIR)-mediated thermal ablation of tumor cells because they efficiently convert absorbed NIR light into heat. Despite the therapeutic potential of SWNTs, there have been no published studies that directly quantify how many SWNTs need be associated with a cell to achieve a desired efficiency of killing, or what is the most efficient subcellular location of SWNTs for killing cells. Herein we measured dose response curves for the efficiency of killing correlated to the measured amounts of folate-targeted SWNTs that were either on the surface or within the vacuolar compartment of normal rat kidney cells. Folate-targeted SWNTs on the cell surface were measured after different concentrations of SWNTs in medium were incubated with cells for 30 min at 4 °C. Folate-targeted SWNTs within the vacuolar compartments were measured after cells were incubated with different concentrations of SWNTs in medium for 6 h at 37 °C. It was observed that a SWNT load of ∼13 pg/cell when internalized was sufficient to kill 90% of the cells under standardized conditions of NIR light irradiation. When ∼3.5 pg/cell of SWNTs were internalized within the endosomal/lysosomal compartments, ∼50% of the cells were killed, but when ∼3.5 pg/cell of SWNTs were confined to the cell surface only ∼5% of the cells were killed under the same NIR irradiation conditions. The SWNT subcellular locations were verified using Raman imaging of SWNTs merged with fluorescence images of known subcellular markers. To our knowledge, this is the first time that SWNT amounts at known subcellular locations have been correlated with a dose-normalized efficacy of thermal ablation and the results support the idea that SWNTs confined to the plasma membrane are not as effective in NIR-mediated cell killing as an equivalent amount of SWNTs when internalized within the endosomal/lysosomal vesicles.

  2. The IQD Family of Calmodulin-Binding Proteins Links Calcium Signaling to Microtubules, Membrane Subdomains, and the Nucleus.

    Science.gov (United States)

    Bürstenbinder, Katharina; Möller, Birgit; Plötner, Romina; Stamm, Gina; Hause, Gerd; Mitra, Dipannita; Abel, Steffen

    2017-03-01

    Calcium (Ca 2+ ) signaling and dynamic reorganization of the cytoskeleton are essential processes for the coordination and control of plant cell shape and cell growth. Calmodulin (CaM) and closely related calmodulin-like (CML) polypeptides are principal sensors of Ca 2+ signals. CaM/CMLs decode and relay information encrypted by the second messenger via differential interactions with a wide spectrum of targets to modulate their diverse biochemical activities. The plant-specific IQ67 DOMAIN (IQD) family emerged as possibly the largest class of CaM-interacting proteins with undefined molecular functions and biological roles. Here, we show that the 33 members of the IQD family in Arabidopsis ( Arabidopsis thaliana ) differentially localize, using green fluorescent protein (GFP)-tagged proteins, to multiple and distinct subcellular sites, including microtubule (MT) arrays, plasma membrane subdomains, and nuclear compartments. Intriguingly, the various IQD-specific localization patterns coincide with the subcellular patterns of IQD-dependent recruitment of CaM, suggesting that the diverse IQD members sequester Ca 2+ -CaM signaling modules to specific subcellular sites for precise regulation of Ca 2+ -dependent processes. Because MT localization is a hallmark of most IQD family members, we quantitatively analyzed GFP-labeled MT arrays in Nicotiana benthamiana cells transiently expressing GFP-IQD fusions and observed IQD-specific MT patterns, which point to a role of IQDs in MT organization and dynamics. Indeed, stable overexpression of select IQD proteins in Arabidopsis altered cellular MT orientation, cell shape, and organ morphology. Because IQDs share biochemical properties with scaffold proteins, we propose that IQD families provide an assortment of platform proteins for integrating CaM-dependent Ca 2+ signaling at multiple cellular sites to regulate cell function, shape, and growth. © 2017 American Society of Plant Biologists. All Rights Reserved.

  3. The IQD Family of Calmodulin-Binding Proteins Links Calcium Signaling to Microtubules, Membrane Subdomains, and the Nucleus1[OPEN

    Science.gov (United States)

    Plötner, Romina; Stamm, Gina; Hause, Gerd; Mitra, Dipannita; Abel, Steffen

    2017-01-01

    Calcium (Ca2+) signaling and dynamic reorganization of the cytoskeleton are essential processes for the coordination and control of plant cell shape and cell growth. Calmodulin (CaM) and closely related calmodulin-like (CML) polypeptides are principal sensors of Ca2+ signals. CaM/CMLs decode and relay information encrypted by the second messenger via differential interactions with a wide spectrum of targets to modulate their diverse biochemical activities. The plant-specific IQ67 DOMAIN (IQD) family emerged as possibly the largest class of CaM-interacting proteins with undefined molecular functions and biological roles. Here, we show that the 33 members of the IQD family in Arabidopsis (Arabidopsis thaliana) differentially localize, using green fluorescent protein (GFP)-tagged proteins, to multiple and distinct subcellular sites, including microtubule (MT) arrays, plasma membrane subdomains, and nuclear compartments. Intriguingly, the various IQD-specific localization patterns coincide with the subcellular patterns of IQD-dependent recruitment of CaM, suggesting that the diverse IQD members sequester Ca2+-CaM signaling modules to specific subcellular sites for precise regulation of Ca2+-dependent processes. Because MT localization is a hallmark of most IQD family members, we quantitatively analyzed GFP-labeled MT arrays in Nicotiana benthamiana cells transiently expressing GFP-IQD fusions and observed IQD-specific MT patterns, which point to a role of IQDs in MT organization and dynamics. Indeed, stable overexpression of select IQD proteins in Arabidopsis altered cellular MT orientation, cell shape, and organ morphology. Because IQDs share biochemical properties with scaffold proteins, we propose that IQD families provide an assortment of platform proteins for integrating CaM-dependent Ca2+ signaling at multiple cellular sites to regulate cell function, shape, and growth. PMID:28115582

  4. Subcellular targeting and biosynthesis of cyclotides in plant cells.

    Science.gov (United States)

    Conlan, Brendon F; Gillon, Amanda D; Barbeta, Barbara L; Anderson, Marilyn A

    2011-12-01

    The cyclotide kalata B1 is found in the leaves of Oldenlandia affinis and is a potent insecticidal and nematocidal molecule. This peptide is cleaved from a precursor protein, Oak1, and ligation of the N- and C-termini occurs to form a continuous peptide backbone. The subcellular location of the excision and cyclization reactions is unknown, and there is debate as to which enzyme catalyzes the event. To determine where in the plant cell Oak1 is processed, we prepared constructs encoding GFP (green fluorescent protein) linked to the cyclotide precursor Oak1. The GFP constructs were transiently expressed in the leaves of Nicotiana benthamiana, and GFP fluorescence was observed in living cells using confocal microscopy. A Fei Mao (FM) styryl dye was infiltrated into whole leaves that were still growing and expressing GFP constructs, enabling the plasma membrane and the tonoplast to be highlighted for visualization of the vacuole in living cells. The full length Oak1 precursor directed GFP to the vacuole, suggesting that excision and cyclization of the cyclotide domain occurs in the vacuole where the cyclotides are then stored. The N-terminal propeptide and N-terminal repeat of Oak1 were both sufficient to target GFP to the vacuole, although the C-terminal propeptide, which is essential for cyclization, was not a targeting signal. The vacuolar location of cyclotides supports our hypothesis that the vacuolar processing enzyme, asparaginyl endoproteinase, has a pivotal role in excision and cyclization from cyclotide precursors.

  5. Structure-function analysis of barley NLR immune receptor MLA10 reveals its cell compartment specific activity in cell death and disease resistance.

    Directory of Open Access Journals (Sweden)

    Shiwei Bai

    Full Text Available Plant intracellular immune receptors comprise a large number of multi-domain proteins resembling animal NOD-like receptors (NLRs. Plant NLRs typically recognize isolate-specific pathogen-derived effectors, encoded by avirulence (AVR genes, and trigger defense responses often associated with localized host cell death. The barley MLA gene is polymorphic in nature and encodes NLRs of the coiled-coil (CC-NB-LRR type that each detects a cognate isolate-specific effector of the barley powdery mildew fungus. We report the systematic analyses of MLA10 activity in disease resistance and cell death signaling in barley and Nicotiana benthamiana. MLA10 CC domain-triggered cell death is regulated by highly conserved motifs in the CC and the NB-ARC domains and by the C-terminal LRR of the receptor. Enforced MLA10 subcellular localization, by tagging with a nuclear localization sequence (NLS or a nuclear export sequence (NES, shows that MLA10 activity in cell death signaling is suppressed in the nucleus but enhanced in the cytoplasm. By contrast, nuclear localized MLA10 is sufficient to mediate disease resistance against powdery mildew fungus. MLA10 retention in the cytoplasm was achieved through attachment of a glucocorticoid receptor hormone-binding domain (GR, by which we reinforced the role of cytoplasmic MLA10 in cell death signaling. Together with our data showing an essential and sufficient nuclear MLA10 activity in disease resistance, this suggests a bifurcation of MLA10-triggered cell death and disease resistance signaling in a compartment-dependent manner.

  6. Selective Fasciotomy for Chronic Exertional Compartment Syndrome Detected With Exercise Magnetic Resonance Imaging.

    Science.gov (United States)

    Park, Sehan; Lee, Ho Seong; Seo, Sang Gyo

    2017-11-01

    Chronic exertional compartment syndrome that is refractory to conservative management should be treated with surgical fasciotomy. However, owing to the limitations of intracompartmental needle manometry in reaching a definite diagnosis, the appropriate timing for fasciotomy and on which compartment remain unclear. The authors report the case of a 22-year-old male military cadet who reported pain in his left calf when running or walking for long distances. The pain was located at the lateral aspect of the calf, from the mid-calf level to the ankle. At another hospital, nonenhanced magnetic resonance imaging had been performed, which showed no considerable abnormality. The authors used exercise magnetic resonance imaging to diagnose chronic exertional compartment syndrome. They performed selective fasciotomy on the compartment that showed a high signal intensity. As a military cadet, the patient was required to jog for more than an hour per day and perform strenuous muscle exercises. He reported that he did not have calf pain or discomfort during such activities 13 months postoperatively. The authors obtained a follow-up exercise magnetic resonance image. Compared with the preoperative magnetic resonance image, the follow-up exercise magnetic resonance image did not show high signal intensity at the lateral compartment. Exercise magnetic resonance imaging is useful in confirming the diagnosis of chronic exertional compartment syndrome and enables the performance of selective fasciotomy on the affected compartment. [Orthopedics. 2017; 40(6):e1099-e1102.]. Copyright 2017, SLACK Incorporated.

  7. Chronic exertional compartment syndrome of the superficial posterior compartment: Soleus syndrome

    OpenAIRE

    Christopher E Gross; Bela J Parekh; Samuel B Adams; Selene G Parekh

    2015-01-01

    Chronic exertional compartment syndrome (CECS) represents the second most-common cause of exertional leg pain with incidence of 27-33%. CECS of the superficial posterior compartment, or soleus syndrome, is rare and has only been discussed briefly in the literature. We discuss the management of two patients with bilateral soleus syndrome or CECS of the superficial posterior compartment.

  8. Chronic exertional compartment syndrome of the superficial posterior compartment: Soleus syndrome.

    Science.gov (United States)

    Gross, Christopher E; Parekh, Bela J; Adams, Samuel B; Parekh, Selene G

    2015-01-01

    Chronic exertional compartment syndrome (CECS) represents the second most-common cause of exertional leg pain with incidence of 27-33%. CECS of the superficial posterior compartment, or soleus syndrome, is rare and has only been discussed briefly in the literature. We discuss the management of two patients with bilateral soleus syndrome or CECS of the superficial posterior compartment.

  9. Management of chronic exertional compartment syndrome

    African Journals Online (AJOL)

    Common symptoms were isolated muscle pain in the anterolateral compartments in all patients, paraesthesia in 15% and swelling in 10%. Post-exercise mean compartment pressure was 61 mmHg (normal <30 mmHg). Modified open fasciotomies were performed by lateral and medial incisions in lower limbs and by a ...

  10. Abdominal Compartment Syndrome in Surgical Patients

    African Journals Online (AJOL)

    level that the abdominal wall compliance threshold is exceeded and the abdomen can no longer stretch, at which point continued accumulation results in very high pressure within this compartment (2). The harmful effects of IAH occur long before the manifestation of compartment syndrome (3). When this is not recognized ...

  11. Clinical aspects of lower leg compartment syndrome

    NARCIS (Netherlands)

    Brand, Johan Gerard Henric van den

    2004-01-01

    A compartment syndrome is a condition in which increased pressure within a limited space compromises the circulation and function of tissues within that space. Although pathofysiology is roughly similar in chronic exertional and acute compartment syndrome of the lower leg, the clinical

  12. 49 CFR 38.127 - Sleeping compartments.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Sleeping compartments. 38.127 Section 38.127 Transportation Office of the Secretary of Transportation AMERICANS WITH DISABILITIES ACT (ADA) ACCESSIBILITY SPECIFICATIONS FOR TRANSPORTATION VEHICLES Intercity Rail Cars and Systems § 38.127 Sleeping compartments. (a...

  13. Protein Tyrosine Kinase Signaling During Oocyte Maturation and Fertilization

    Science.gov (United States)

    McGinnis, Lynda K.; Carroll, David J.; Kinsey, William H.

    2011-01-01

    The oocyte is a highly specialized cell capable of accumulating and storing energy supplies as well as maternal transcripts and pre-positioned signal transduction components needed for zygotic development, undergoing meiosis under control of paracrine signals from the follicle, fusing with a single sperm during fertilization, and zygotic development. The oocyte accomplishes this diverse series of events by establishing an array of signal transduction pathway components that include a select collection of protein tyrosine kinases (PTKs) that are expressed at levels significantly higher than most other cell types. This array of PTKs includes cytosolic kinases such as SRC-family PTKs (FYN and YES), and FAK kinases, as well as FER. These kinases typically exhibit distinct patterns of localization and in some cases are translocated from one subcellular compartment to another during meiosis. Significant differences exist in the extent to which PTK-mediated pathways are used by oocytes from species that fertilize externally versus internally. The PTK activation profiles as well as calcium signaling pattern seems to correlate with the extent to which a rapid block to polyspermy is required by the biology of each species. Suppression of each of the SRC-family PTKs as well as FER kinase results in failure of meiotic maturation or zygote development, indicating that these PTKs are important for oocyte quality and developmental potential. Future studies will hopefully reveal the extent to which these factors impact clinical assisted reproductive techniques in domestic animals and humans. PMID:21681843

  14. KCC2-dependent subcellular ECl difference of ON-OFF retinal ganglion cells in larval zebrafish

    Directory of Open Access Journals (Sweden)

    Rongwei eZhang

    2013-05-01

    Full Text Available Subcellular difference in the reversal potential of Cl- (ECl has been found in many types of neurons. As local ECl largely determines the action of nearby GABAergic/glycinergic synapses, subcellular ECl difference can effectively regulate neuronal computation. The ON-OFF retinal ganglion cell (RGC processes both ON and OFF visual signals via its ON and OFF dendrites, respectively. It is thus interesting to investigate whether the ON and OFF dendrites of single RGCs exhibit different local ECl. Here, using in vivo gramicidin-perforated patch recording in larval zebrafish ON-OFF RGCs, we examine local ECl at the ON and OFF dendrites, and soma through measuring light-evoked ON and OFF inhibitory responses, and GABA-induced response at the soma, respectively. We find there are subcellular ECl differences between the soma and dendrite, as well as between the ON and OFF dendrites of single RGCs. These somato-dendritic and inter-dendritic ECl differences are dependent on the Cl- extruder, K+/Cl- co-transporter (KCC2, because they are largely diminished by down-regulating kcc2 expression with morpholino oligonucleotides or by blocking KCC2 function with furosemide. Thus, our findings indicate that there exists KCC2-dependent ECl difference between the ON and OFF dendrites of individual ON-OFF RGCs that may differentially affect visual processing in the ON and OFF pathways.

  15. Differential subcellular distribution of four phospholipase C isoforms and secretion of GPI-PLC activity.

    Science.gov (United States)

    Staudt, Emanuel; Ramasamy, Pathmanaban; Plattner, Helmut; Simon, Martin

    2016-12-01

    Phospholipase C (PLC) is an important enzyme of signal transduction pathways by generation of second messengers from membrane lipids. PLCs are also indicated to cleave glycosylphosphatidylinositol (GPI)-anchors of surface proteins thus releasing these into the environment. However, it remains unknown whether this enzymatic activity on the surface is due to distinct PLC isoforms in higher eukaryotes. Ciliates have, in contrast to other unicellular eukaryotes, multiple PLC isoforms as mammals do. Thus, Paramecium represents a perfect model to study subcellular distribution and potential surface activity of PLC isoforms. We have identified distinct subcellular localizations of four PLC isoforms indicating functional specialization. The association with different calcium release channels (CRCs) argues for distinct subcellular functions. They may serve as PI-PLCs in microdomains for local second messenger responses rather than free floating IP3. In addition, all isoforms can be found on the cell surface and they are found together with GPI-cleaved surface proteins in salt/ethanol washes of cells. We can moreover show them in medium supernatants of living cells where they have access to GPI-anchored surface proteins. Among the isoforms we cannot assign GPI-PLC activity to specific PLC isoforms; rather each PLC is potentially responsible for the release of GPI-anchored proteins from the surface. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. A formal ontology of subcellular neuroanatomy

    Directory of Open Access Journals (Sweden)

    Stephen D Larson

    2007-11-01

    Full Text Available The complexity of the nervous system requires high-resolution microscopy to resolve the detailed 3D structure of nerve cells and supracellular domains. The analysis of such imaging data to extract cellular surfaces and cell components often requires the combination of expert human knowledge with carefully engineered software tools. In an effort to make better tools to assist humans in this endeavor, create a more accessible and permanent record of their data, and to aid the process of constructing complex and detailed computational models, we have created a core of formalized knowledge about the structure of the nervous system and have integrated that core into several software applications. In this paper, we describe the structure and content of a formal ontology whose scope is the subcellular anatomy of the nervous system (SAO, covering nerve cells, their parts, and interactions between these parts. Many applications of this ontology to image annotation, content-based retrieval of structural data, and integration of shared data across scales and researchers are also described.

  17. Subcellular drug targeting, pharmacokinetics and bioavailability.

    Science.gov (United States)

    Leucuta, Sorin Emilian

    2014-02-01

    Effective treatment of diseases at the molecular level is possible by directing the drug substance (micromolecular, protein or peptide drugs, DNA, oligonucleotides, siRNA) with the aid of a specialized nanoparticulate carrier, for safe and effective transport to the specific site of action in the cytosol and its organelles including nuclear targeting. To achieve efficient cytosolic delivery of therapeutics or nuclear targeting, different drug delivery systems (DDS) have been developed (macromolecular drug conjugates, chemically or genetically modified proteins, and particulate drug carriers) capable of subcellular internalization overcoming the biological barriers, by passive targeting and especially by active targeting (receptor-targeted delivery). The success depends on the physicochemical nature of DDS, intracellular barriers that these systems need to overcome, the bioavailability of the bioactive drug, biodistribution, the intracellular pharmacokinetics and its influence on the pharmacodynamic effect. Models necessary for this purpose exist but they need to be more developed especially with quantitative treatments, after the development of the means of highlighting the evolution of the drug substance in biophase or at the level of the target cellular organelle by quantitative assays. It is expected that intracellularly targeted drug delivery approaches will be clinically useful using specialized DDSs belonging to the pharmaceutical nanotechnologies.

  18. Tau regulates the subcellular localization of calmodulin

    Energy Technology Data Exchange (ETDEWEB)

    Barreda, Elena Gomez de [Centro de Biologia Molecular ' Severo Ochoa' , CSIC/UAM, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Avila, Jesus, E-mail: javila@cbm.uam.es [Centro de Biologia Molecular ' Severo Ochoa' , CSIC/UAM, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); CIBER de Enfermedades Neurodegenerativas, 28031 Madrid (Spain)

    2011-05-13

    Highlights: {yields} In this work we have tried to explain how a cytoplasmic protein could regulate a cell nuclear function. We have tested the role of a cytoplasmic protein (tau) in regulating the expression of calbindin gene. We found that calmodulin, a tau-binding protein with nuclear and cytoplasmic localization, increases its nuclear localization in the absence of tau. Since nuclear calmodulin regulates calbindin expression, a decrease in nuclear calmodulin, due to the presence of tau that retains it at the cytoplasm, results in a change in calbindin expression. -- Abstract: Lack of tau expression in neuronal cells results in a change in the expression of few genes. However, little is known about how tau regulates gene expression. Here we show that the presence of tau could alter the subcellular localization of calmodulin, a protein that could be located at the cytoplasm or in the nucleus. Nuclear calmodulin binds to co-transcription factors, regulating the expression of genes like calbindin. In this work, we have found that in neurons containing tau, a higher proportion of calmodulin is present in the cytoplasm compared with neurons lacking tau and that an increase in cytoplasmic calmodulin correlates with a higher expression of calbindin.

  19. Spontaneous Extensor Carpi Ulnaris Compartment Syndrome.

    Science.gov (United States)

    Stewart, Sarah K; Singleton, James A G

    2016-06-01

    We report a case of isolated compartment syndrome within the extensor carpi ulnaris (ECU) compartment in the forearm of a 40-year-old diabetic man. Magnetic resonance imaging of his forearm showed isolated changes in the ECU muscle belly; compartment syndrome was confirmed on manometry. In view of the short history of symptoms and his diabetic status, the patient was managed conservatively. Twenty-four hours after onset of the symptoms, the pain and swelling resolved and he was able to be discharged. To date, 3 cases of ECU compartment syndrome secondary to trauma have been reported. This report illustrates a case of confirmed compartment syndrome without antecedent trauma, highly unusual in terms of both its etiology and its anatomical location. Copyright © 2016 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  20. The subcellular fate of cadmium and zinc in the scallop Chlamys nobilis during waterborne and dietary metal exposure

    Energy Technology Data Exchange (ETDEWEB)

    Pan Ke [Department of Biology, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon (Hong Kong); Wang Wenxiong [Department of Biology, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon (Hong Kong)], E-mail: wwang@ust.hk

    2008-12-11

    Subcellular metal distribution has received increasing attention in aquatic toxicology studies, but the relationship between metal distribution and metal biokinetics remains largely unexplored. A series of short-term experiments on different concentrations of dissolved and dietary metals and on metal elimination were conducted to investigate the dynamics of subcellular distribution of Cd and Zn in the scallop Chlamys nobilis, a bivalve species that is known to accumulate very high concentrations of Cd and Zn in its tissues. Our results showed that, in general, both Cd and Zn were sequestered in insoluble forms (organelles, metal-rich granules, and cellular debris). The main binding pool for the newly acquired metals was organelles for Cd and cellular debris for Zn. Metallothionein-like protein (MTLP) was the most important storage pool for Cd in the scallops. Storage in the non-toxic form both in organelles and MTLP instead of through exocytosis was the major detoxification strategy to control Cd and accounted for the low efflux rate of Cd from scallops. In contrast to Cd, the main binding pool for Zn was cellular debris. Significant changes were found in the scallops when they were challenged with different concentrations of metals in the aqueous and food phases. Such changes provide important information on how scallops handle metals when there is increasing metal uptake. The redistribution of Zn among each subcellular compartment was much faster than the redistribution of Cd, suggesting an effective regulation mechanism for Zn in scallops. Thus, knowing subcellular metal distribution helps in studying the toxicity of both waterborne and dietborne metals.

  1. Tissue and subcellular distribution of CLIC1

    Directory of Open Access Journals (Sweden)

    Edwards John C

    2007-02-01

    Full Text Available Abstract Background CLIC1 is a chloride channel whose cellular role remains uncertain. The distribution of CLIC1 in normal tissues is largely unknown and conflicting data have been reported regarding the cellular membrane fraction in which CLIC1 resides. Results New antisera to CLIC1 were generated and were found to be sensitive and specific for detecting this protein. These antisera were used to investigate the distribution of CLIC1 in mouse tissue sections and three cultured cell lines. We find CLIC1 is expressed in the apical domains of several simple columnar epithelia including glandular stomach, small intestine, colon, bile ducts, pancreatic ducts, airway, and the tail of the epididymis, in addition to the previously reported renal proximal tubule. CLIC1 is expressed in a non-polarized distribution in the basal epithelial cell layer of the stratified squamous epithelium of the upper gastrointesitinal tract and the basal cells of the epididymis, and is present diffusely in skeletal muscle. Distribution of CLIC1 was examined in Panc1 cells, a relatively undifferentiated, non-polarized human cell line derived from pancreatic cancer, and T84 cells, a human colon cancer cell line which can form a polarized epithelium that is capable of regulated chloride transport. Digitonin extraction was used to distinguish membrane-inserted CLIC1 from the soluble cytoplasmic form of the protein. We find that digitonin-resistant CLIC1 is primarily present in the plasma membrane of Panc1 cells. In T84 cells, we find digitonin-resistant CLIC1 is present in an intracellular compartment which is concentrated immediately below the apical plasma membrane and the extent of apical polarization is enhanced with forskolin, which activates transepithelial chloride transport and apical membrane traffic in these cells. The sub-apical CLIC1 compartment was further characterized in a well-differentiated mouse renal proximal tubule cell line. The distribution of CLIC1 was

  2. Sub-cellular distribution and translocation of TRP channels.

    Science.gov (United States)

    Toro, Carlos A; Arias, Luis A; Brauchi, Sebastian

    2011-01-01

    Cellular electrical activity is the result of a highly complex processes that involve the activation of ion channel proteins. Ion channels make pores on cell membranes that rapidly transit between conductive and non-conductive states, allowing different ions to flow down their electrochemical gradients across cell membranes. In the case of neuronal cells, ion channel activity orchestrates action potentials traveling through axons, enabling electrical communication between cells in distant parts of the body. Somatic sensation -our ability to feel touch, temperature and noxious stimuli- require ion channels able to sense and respond to our peripheral environment. Sensory integration involves the summing of various environmental cues and their conversion into electrical signals. Members of the Transient Receptor Potential (TRP) family of ion channels have emerged as important mediators of both cellular sensing and sensory integration. The regulation of the spatial and temporal distribution of membrane receptors is recognized as an important mechanism for controlling the magnitude of the cellular response and the time scale on which cellular signaling occurs. Several studies have shown that this mechanism is also used by TRP channels to modulate cellular response and ultimately fulfill their physiological function as sensors. However, the inner-working of this mode of control for TRP channels remains poorly understood. The question of whether TRPs intrinsically regulate their own vesicular trafficking or weather the dynamic regulation of TRP channel residence on the cell surface is caused by extrinsic changes in the rates of vesicle insertion or retrieval remain open. This review will examine the evidence that sub-cellular redistribution of TRP channels plays an important role in regulating their activity and explore the mechanisms that control the trafficking of vesicles containing TRP channels.

  3. Characterization of RanBPM Molecular Determinants that Control Its Subcellular Localization

    Science.gov (United States)

    Salemi, Louisa M.; Loureiro, Sandra O.; Schild-Poulter, Caroline

    2015-01-01

    RanBPM/RanBP9 is a ubiquitous, nucleocytoplasmic protein that is part of an evolutionary conserved E3 ubiquitin ligase complex whose function and targets in mammals are still unknown. RanBPM itself has been implicated in various cellular processes that involve both nuclear and cytoplasmic functions. However, to date, little is known about how RanBPM subcellular localization is regulated. We have conducted a systematic analysis of RanBPM regions that control its subcellular localization using RanBPM shRNA cells to examine ectopic RanBPM mutant subcellular localization without interference from the endogenously expressed protein. We show that several domains and motifs regulate RanBPM nuclear and cytoplasmic localization. In particular, RanBPM comprises two motifs that can confer nuclear localization, one proline/glutamine-rich motif in the extreme N-terminus which has a dominant effect on RanBPM localization, and a second motif in the C-terminus which minimally contributes to RanBPM nuclear targeting. We also identified a nuclear export signal (NES) which mutation prevented RanBPM accumulation in the cytoplasm. Likewise, deletion of the central RanBPM conserved domains (SPRY and LisH/CTLH) resulted in the relocalization of RanBPM to the nucleus, suggesting that RanBPM cytoplasmic localization is also conferred by protein-protein interactions that promote its cytoplasmic retention. Indeed we found that in the cytoplasm, RanBPM partially colocalizes with microtubules and associates with α-tubulin. Finally, in the nucleus, a significant fraction of RanBPM is associated with chromatin. Altogether, these analyses reveal that RanBPM subcellular localization results from the combined effects of several elements that either confer direct transport through the nucleocytoplasmic transport machinery or regulate it indirectly, likely through interactions with other proteins and by intramolecular folding. PMID:25659156

  4. HECTAR: a method to predict subcellular targeting in heterokonts

    National Research Council Canada - National Science Library

    Gschloessl, Bernhard; Guermeur, Yann; Cock, J Mark

    2008-01-01

    .... To understand the biology of these organisms, it is necessary to be able to predict the subcellular localisation of their proteins but this is not straightforward, particularly in photosynthetic...

  5. Role of an acidic compartment in synthesis of disaturated phosphatidylcholine by rat granular pneumocytes

    Science.gov (United States)

    Chander, Avinash; Fisher, Aron B.; Strauss, Jerome F.

    1982-01-01

    A possible role for an acidic subcellular compartment in biosynthesis of lung surfactant phospholipids was evaluated with granular pneumocytes in primary culture. Incubation with chloroquine (100μm) was used to perturb this compartment. With control cells, incorporation of [9,10-3H]palmitic acid into total lipids and into total phosphatidylcholines increased linearly with time up to 4h. Total incorporation into phosphatidylcholine during a 1h incubation was 999+85pmol of [9,10-3H]palmitic acid, 458±18pmol of [1-14C]oleic acid and 252±15pmol of [U-14C]glucose per μg of phosphatidylcholine phosphorus. The cellular content of either disaturated phosphatidylcholine or total phosphatidylcholines did not change during a 2h incubation with chloroquine. In the presence of chloroquine, the specific radioactivity of [3H]palmitic acid in disaturated phosphatidylcholine increased by 40%, and that of disaturated-phosphatidylcholine fatty acids from [U-14C]glucose increased by 125%. Incorporation of [1-14C]oleic acid into phosphatidylcholine was decreased by chloroquine by 79% and 33% in the presence or absence of palmitic acid respectively. Chloroquine stimulated phospholipase activity in intact cells, and in sonicated cells at pH4.0, but not at pH8.5. The observations indicate that chloroquine stimulates synthesis of disaturated phosphatidylcholine in granular pneumocytes from fatty acids, both exogenous and synthesized de novo, which can be due to stimulation of acidic phospholipase. This stimulation of acidic phospholipase A activity by chloroquine appears to be coupled to the synthesis of disaturated phosphatidylcholine, thereby enhancing remodelling of phosphatidylcholine synthesized de novo. Our findings, therefore, implicate the involvement of an acidic subcellular compartment in the remodelling pathway of disaturated phosphatidylcholine synthesis by granular pneumocytes. ImagesPLATE 1 PMID:7165723

  6. Subcellular analysis by laser ablation electrospray ionization mass spectrometry

    Science.gov (United States)

    Vertes, Akos; Stolee, Jessica A; Shrestha, Bindesh

    2014-12-02

    In various embodiments, a method of laser ablation electrospray ionization mass spectrometry (LAESI-MS) may generally comprise micro-dissecting a cell comprising at least one of a cell wall and a cell membrane to expose at least one subcellular component therein, ablating the at least one subcellular component by an infrared laser pulse to form an ablation plume, intercepting the ablation plume by an electrospray plume to form ions, and detecting the ions by mass spectrometry.

  7. Recurrent Lower-Extremity Compartment Syndrome after Four-Compartment Fasciotomy Secondary to Acute Limb Ischemia.

    Science.gov (United States)

    Kerkar, Ashwini P; Farber, Alik; Kalish, Jeffrey A; Siracuse, Jeffrey J

    2016-01-01

    Lower-extremity compartment syndrome is a limb-threatening event necessitating emergent treatment using fasciotomy. Recurrent compartment syndrome is rare and has only been reported after trauma and in conjunction with underlying connective tissue disorders. In this report, we present a case of recurrent lower-extremity compartment syndrome caused by ischemia-reperfusion injury, in a patient previously treated with adequate 4-compartment fasciotomies. As such, this is the first reported case of recurrent compartment syndrome in the setting of ischemia-reperfusion injury that required treatment with 4-compartment fasciotomies on both occasions. This case demonstrates that fasciotomy is not protective against the development of recurrent compartment syndrome due to ischemia-reperfusion injury and that patients at high risk require monitoring. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Compartment Syndrome of the Leg Associated With Fracture: An Algorithm to Avoid Releasing the Posterior Compartments.

    Science.gov (United States)

    Tornetta, Paul; Puskas, Brian L; Wang, Kevin

    2016-07-01

    The purpose of this study is to report on a prospective series of patients in whom an algorithm was used to attempt to avoid releasing the posterior compartments in patients with lower leg compartment syndrome (CS) and the safety of such a practice. Prospective cohort study. Level 1 trauma center. A consecutive series of 39 patients was managed by one surgeon for CS using the reported protocol. Patients diagnosed with a CS of the leg were managed with a single operative protocol. After a standard anterior and lateral compartment release through a full-length lateral incision was performed, the superficial and deep posterior compartments were measured with the heel resting on a bolster. Using the preoperative diastolic blood pressure, a ΔP compartments. If the ΔP was ≥30, the posterior compartments were not released. Need for medial release or development of posterior CS or sequelae. A consecutive series of 39 patients were managed by 1 surgeon for CS using the described protocol. Two patients with an isolated posterior CS were excluded. The other 37 had clinical symptoms or compartment pressures consistent with anterior compartment involvement. Of 37 patients, 21 had (57%) symptoms suggesting posterior compartment involvement. The preoperative pressure measurements averaged 41 mm Hg with an average ΔP of 38. After full-length release of the anterior and lateral compartments, only 3/37 (8%) required a posterior release for a ΔP of compartments of the remaining 34 patients averaged 59 (32-86). The compartment pressures in the superficial and deep posterior compartments decreased by 22 mm Hg and 24 mm Hg, respectively, after the anterolateral release. None of the patients who had only an anterolateral release developed sequelae of a missed posterior CS. The use of the reported algorithm is effective in avoiding posterior compartment release. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

  9. High resolution imaging of subcellular glutathione concentrations by quantitative immunoelectron microscopy in different leaf areas of Arabidopsis

    Science.gov (United States)

    Koffler, Barbara E.; Bloem, Elke; Zellnig, Günther; Zechmann, Bernd

    2013-01-01

    Glutathione is an important antioxidant and redox buffer in plants. It fulfills many important roles during plant development, defense and is essential for plant metabolism. Even though the compartment specific roles of glutathione during abiotic and biotic stress situations have been studied in detail there is still great lack of knowledge about subcellular glutathione concentrations within the different leaf areas at different stages of development. In this study a method is described that allows the calculation of compartment specific glutathione concentrations in all cell compartments simultaneously in one experiment by using quantitative immunogold electron microscopy combined with biochemical methods in different leaf areas of Arabidopsis thaliana Col-0 (center of the leaf, leaf apex, leaf base and leaf edge). The volume of subcellular compartments in the mesophyll of Arabidopsis was found to be similar to other plants. Vacuoles covered the largest volume within a mesophyll cell and increased with leaf age (up to 80% in the leaf apex of older leaves). Behind vacuoles, chloroplasts covered the second largest volume (up to 20% in the leaf edge of the younger leaves) followed by nuclei (up to 2.3% in the leaf edge of the younger leaves), mitochondria (up to 1.6% in the leaf apex of the younger leaves), and peroxisomes (up to 0.3% in the leaf apex of the younger leaves). These values together with volumes of the mesophyll determined by stereological methods from light and electron micrographs and global glutathione contents measured with biochemical methods enabled the determination of subcellular glutathione contents in mM. Even though biochemical investigations did not reveal differences in global glutathione contents, compartment specific differences could be observed in some cell compartments within the different leaf areas. Highest concentrations of glutathione were always found in mitochondria, where values in a range between 8.7 mM (in the apex of younger

  10. Evaluation of acute compartment syndrome of extremities in ...

    African Journals Online (AJOL)

    Arun Kumar Agnihotri

    presenting with clinically suspected acute compartment syndrome were studied. These were divided into two age related groups: ... compartment syndrome in children; Acute compartment syndrome and fasciotomy. INTRODUCTIONᴪ ... immobilization, wound management, numbers of surgical procedures until definitive ...

  11. SPA Proteins Affect the Subcellular Localization of COP1 in the COP1/SPA Ubiquitin Ligase Complex during Photomorphogenesis.

    Science.gov (United States)

    Balcerowicz, Martin; Kerner, Konstantin; Schenkel, Christian; Hoecker, Ute

    2017-07-01

    The Arabidopsis ( Arabidopsis thaliana ) COP1/SPA ubiquitin ligase is a central repressor that suppresses light signaling in darkness by targeting positive regulators of the light response, mainly transcription factors, for degradation. Light inactivates COP1/SPA, in part by excluding COP1 from the nucleus. SPA proteins are essential cofactors of COP1, but their exact role in the COP1/SPA complex is thus far unknown. To unravel a potential role of SPA proteins in COP1 nucleocytoplasmic partitioning, we monitored the subcellular localization of COP1 in a spa1234 quadruple mutant ( spaQn ). We analyzed a YFP-COP1-expressing transgenic line and endogenous COP1 after subcellular fractionation. In dark-grown seedlings, both YFP-COP1 and endogenous COP1 accumulated in the nucleus in the absence and presence of SPA proteins, indicating that SPA proteins are not required for nuclear localization of COP1 in darkness. In contrast, in white light-grown seedlings, spaQn mutants failed to relocalize COP1 from the nucleus to the cytoplasm. Hence, SPA proteins are necessary for the light-controlled change in COP1 subcellular localization. We conclude that SPA proteins have a dual role: (1) they are required for light-responsiveness of COP1 subcellular localization, and (2) they promote COP1 activity in darkness in a fashion that is independent of the nuclear import/nuclear retention of COP1. © 2017 American Society of Plant Biologists. All Rights Reserved.

  12. 14 CFR 25.771 - Pilot compartment.

    Science.gov (United States)

    2010-01-01

    ... compartment must be constructed so that, when flying in rain or snow, it will not leak in a manner that will distract the crew or harm the structure. (e) Vibration and noise characteristics of cockpit equipment may...

  13. Engineered protein nano-compartments for targeted enzyme localization.

    Directory of Open Access Journals (Sweden)

    Swati Choudhary

    Full Text Available Compartmentalized co-localization of enzymes and their substrates represents an attractive approach for multi-enzymatic synthesis in engineered cells and biocatalysis. Sequestration of enzymes and substrates would greatly increase reaction efficiency while also protecting engineered host cells from potentially toxic reaction intermediates. Several bacteria form protein-based polyhedral microcompartments which sequester functionally related enzymes and regulate their access to substrates and other small metabolites. Such bacterial microcompartments may be engineered into protein-based nano-bioreactors, provided that they can be assembled in a non-native host cell, and that heterologous enzymes and substrates can be targeted into the engineered compartments. Here, we report that recombinant expression of Salmonella enterica ethanolamine utilization (eut bacterial microcompartment shell proteins in E. coli results in the formation of polyhedral protein shells. Purified recombinant shells are morphologically similar to the native Eut microcompartments purified from S. enterica. Surprisingly, recombinant expression of only one of the shell proteins (EutS is sufficient and necessary for creating properly delimited compartments. Co-expression with EutS also facilitates the encapsulation of EGFP fused with a putative Eut shell-targeting signal sequence. We also demonstrate the functional localization of a heterologous enzyme (β-galactosidase targeted to the recombinant shells. Together our results provide proof-of-concept for the engineering of protein nano-compartments for biosynthesis and biocatalysis.

  14. Thigh compartment syndrome during extracorporeal life support.

    Science.gov (United States)

    Kreibich, Maximilian; Czerny, Martin; Benk, Christoph; Beyersdorf, Friedhelm; Rylski, Bartosz; Trummer, Georg

    2017-11-01

    The aim of this study was to report our experience with patients on the extracorporeal life support system (ECLS) who presented with thigh compartment syndrome, a yet unreported complication. A retrospective analysis was performed from April 2003 to April 2017 to identify patients who presented to our department for treatment of acute compartment syndrome of the thigh after cannulation of the ECLS through the femoral artery and vein. Five patients, aged 30 to 84 years, who developed thigh compartment syndrome during ECLS therapy were identified. In three patients, the cause was arterial malperfusion; in one patient, the cause was venous malfunction and arterial malperfusion due to malposition of the arterial distal leg perfusion cannula in the femoral vein. The fifth patient suffered impaired venous drainage. Patients were on ECLS for 4 ± 2 days, and decompressive fasciotomy was performed in all patients 1 ± 1 days after ECLS commencement. Thigh compartment syndrome was responsible for significant morbidity, including prolonged open wound therapy, hospitalization, and leg amputation in one patient. Compartment syndrome of the thigh is a limb- and life-threatening complication and may occur in patients on ECLS. Angiographic or duplex ultrasound control of adequate limb perfusion and correct placement of the perfusion cannulas is recommended. Also, awareness of and close clinical observation for thigh perfusion and compartment syndrome are essential in patients during ECLS therapy. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  15. Human cell structure-driven model construction for predicting protein subcellular location from biological images.

    Science.gov (United States)

    Shao, Wei; Liu, Mingxia; Zhang, Daoqiang

    2016-01-01

    The systematic study of subcellular location pattern is very important for fully characterizing the human proteome. Nowadays, with the great advances in automated microscopic imaging, accurate bioimage-based classification methods to predict protein subcellular locations are highly desired. All existing models were constructed on the independent parallel hypothesis, where the cellular component classes are positioned independently in a multi-class classification engine. The important structural information of cellular compartments is missed. To deal with this problem for developing more accurate models, we proposed a novel cell structure-driven classifier construction approach (SC-PSorter) by employing the prior biological structural information in the learning model. Specifically, the structural relationship among the cellular components is reflected by a new codeword matrix under the error correcting output coding framework. Then, we construct multiple SC-PSorter-based classifiers corresponding to the columns of the error correcting output coding codeword matrix using a multi-kernel support vector machine classification approach. Finally, we perform the classifier ensemble by combining those multiple SC-PSorter-based classifiers via majority voting. We evaluate our method on a collection of 1636 immunohistochemistry images from the Human Protein Atlas database. The experimental results show that our method achieves an overall accuracy of 89.0%, which is 6.4% higher than the state-of-the-art method. The dataset and code can be downloaded from https://github.com/shaoweinuaa/. dqzhang@nuaa.edu.cn Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  16. Expression and subcellular targeting of human complement factor C5a in Nicotiana species.

    Science.gov (United States)

    Nausch, Henrik; Mikschofsky, Heike; Mischofsky, Heike; Koslowski, Roswitha; Meyer, Udo; Broer, Inge; Huckauf, Jana

    2012-01-01

    We evaluated transgenic tobacco plants as an alternative to Escherichia coli for the production of recombinant human complement factor 5a (C5a). C5a has not been expressed in plants before and is highly unstable in vivo in its native form, so it was necessary to establish the most suitable subcellular targeting strategy. We used the strong and constitutive CaMV 35S promoter to drive transgene expression and compared three different subcellular compartments. The yields of C5a in the T(0) transgenic plants were low in terms of the proportion of total soluble protein (TSP) when targeted to the apoplast (0.0002% TSP) or endoplasmic reticulum (0.0003% TSP) but was one order of magnitude higher when targeted to the vacuole (0.001% TSP). The yields could be increased by conventional breeding (up to 0.014% TSP in the T₂ generation). C5a accumulated to the same level in seeds and leaves when targeted to the apoplast but was up to 1.7-fold more abundant in the seeds when targeted to the ER or vacuole, although this difference was less striking in the better-performing lines. When yields were calculated as an amount per gram fresh weight of transgenic plant tissue, the vacuole targeting strategy was clearly more efficient in seeds, reaching 35.8 µg C5a per gram of fresh seed weight compared to 10.62 µg C5a per gram fresh weight of leaves. Transient expression of C5aER and C5aVac in N. benthamiana, using MagnICON vectors, reached up to 0.2% and 0.7% of TSP, respectively, but was accompanied by cytotoxic effects and induced leaf senescence. Western blot of the plant extracts revealed a band matching the corresponding glycosylated native protein and the bioassay demonstrated that recombinant C5a was biologically active.

  17. Expression and subcellular targeting of human complement factor C5a in Nicotiana species.

    Directory of Open Access Journals (Sweden)

    Henrik Nausch

    Full Text Available We evaluated transgenic tobacco plants as an alternative to Escherichia coli for the production of recombinant human complement factor 5a (C5a. C5a has not been expressed in plants before and is highly unstable in vivo in its native form, so it was necessary to establish the most suitable subcellular targeting strategy. We used the strong and constitutive CaMV 35S promoter to drive transgene expression and compared three different subcellular compartments. The yields of C5a in the T(0 transgenic plants were low in terms of the proportion of total soluble protein (TSP when targeted to the apoplast (0.0002% TSP or endoplasmic reticulum (0.0003% TSP but was one order of magnitude higher when targeted to the vacuole (0.001% TSP. The yields could be increased by conventional breeding (up to 0.014% TSP in the T₂ generation. C5a accumulated to the same level in seeds and leaves when targeted to the apoplast but was up to 1.7-fold more abundant in the seeds when targeted to the ER or vacuole, although this difference was less striking in the better-performing lines. When yields were calculated as an amount per gram fresh weight of transgenic plant tissue, the vacuole targeting strategy was clearly more efficient in seeds, reaching 35.8 µg C5a per gram of fresh seed weight compared to 10.62 µg C5a per gram fresh weight of leaves. Transient expression of C5aER and C5aVac in N. benthamiana, using MagnICON vectors, reached up to 0.2% and 0.7% of TSP, respectively, but was accompanied by cytotoxic effects and induced leaf senescence. Western blot of the plant extracts revealed a band matching the corresponding glycosylated native protein and the bioassay demonstrated that recombinant C5a was biologically active.

  18. Accounting for Protein Subcellular Localization: A Compartmental Map of the Rat Liver Proteome.

    Science.gov (United States)

    Jadot, Michel; Boonen, Marielle; Thirion, Jaqueline; Wang, Nan; Xing, Jinchuan; Zhao, Caifeng; Tannous, Abla; Qian, Meiqian; Zheng, Haiyan; Everett, John K; Moore, Dirk F; Sleat, David E; Lobel, Peter

    2017-02-01

    Accurate knowledge of the intracellular location of proteins is important for numerous areas of biomedical research including assessing fidelity of putative protein-protein interactions, modeling cellular processes at a system-wide level and investigating metabolic and disease pathways. Many proteins have not been localized, or have been incompletely localized, partly because most studies do not account for entire subcellular distribution. Thus, proteins are frequently assigned to one organelle whereas a significant fraction may reside elsewhere. As a step toward a comprehensive cellular map, we used subcellular fractionation with classic balance sheet analysis and isobaric labeling/quantitative mass spectrometry to assign locations to >6000 rat liver proteins. We provide quantitative data and error estimates describing the distribution of each protein among the eight major cellular compartments: nucleus, mitochondria, lysosomes, peroxisomes, endoplasmic reticulum, Golgi, plasma membrane and cytosol. Accounting for total intracellular distribution improves quality of organelle assignments and assigns proteins with multiple locations. Protein assignments and supporting data are available online through the Prolocate website (http://prolocate.cabm.rutgers.edu). As an example of the utility of this data set, we have used organelle assignments to help analyze whole exome sequencing data from an infant dying at 6 months of age from a suspected neurodegenerative lysosomal storage disorder of unknown etiology. Sequencing data was prioritized using lists of lysosomal proteins comprising well-established residents of this organelle as well as novel candidates identified in this study. The latter included copper transporter 1, encoded by SLC31A1, which we localized to both the plasma membrane and lysosome. The patient harbors two predicted loss of function mutations in SLC31A1, suggesting that this may represent a heretofore undescribed recessive lysosomal storage disease

  19. Synthetic biology. Programmable on-chip DNA compartments as artificial cells.

    Science.gov (United States)

    Karzbrun, Eyal; Tayar, Alexandra M; Noireaux, Vincent; Bar-Ziv, Roy H

    2014-08-15

    The assembly of artificial cells capable of executing synthetic DNA programs has been an important goal for basic research and biotechnology. We assembled two-dimensional DNA compartments fabricated in silicon as artificial cells capable of metabolism, programmable protein synthesis, and communication. Metabolism is maintained by continuous diffusion of nutrients and products through a thin capillary, connecting protein synthesis in the DNA compartment with the environment. We programmed protein expression cycles, autoregulated protein levels, and a signaling expression gradient, equivalent to a morphogen, in an array of interconnected compartments at the scale of an embryo. Gene expression in the DNA compartment reveals a rich, dynamic system that is controlled by geometry, offering a means for studying biological networks outside a living cell. Copyright © 2014, American Association for the Advancement of Science.

  20. Compartment syndrome after total knee arthroplasty: regarding a clinical case

    Directory of Open Access Journals (Sweden)

    Ana Alexandra da Costa Pinheiro

    2015-08-01

    Full Text Available ABSTRACT Although compartment syndrome is a rare complication of total knee arthroplasty, it is one of the most devastating complications. It is defined as a situation of increased pressure within a closed osteofascial space that impairs the circulation and the functioning of the tissues inside this space, thereby leading to ischemia and tissue dysfunction. Here, a clinical case of a patient who was followed up in orthopedic outpatient consultations due to right gonarthrosis is presented. The patient had a history of arthroscopic meniscectomy and presented knee flexion of 10° before the operation, which consisted of total arthroplasty of the right knee. The operation seemed to be free from intercurrences, but the patient evolved with compartment syndrome of the ipsilateral leg after the operation. Since compartment syndrome is a true surgical emergency, early recognition and treatment of this condition through fasciotomy is crucial in order to avoid amputation, limb dysfunction, kidney failure and death. However, it may be difficult to make the diagnosis and cases may not be recognized if the cause of compartment syndrome is unusual or if the patient is under epidural analgesia and/or peripheral nerve block, which thus camouflages the main warning sign, i.e. disproportional pain. In addition, edema of the limb that underwent the intervention is common after total knee arthroplasty operations. This study presents a review of the literature and signals that the possible rarity of cases is probably due to failure to recognize this condition in a timely manner and to placing these patients in other diagnostic groups that are less likely, such as neuropraxia caused by using a tourniquet or peripheral nerve injury.

  1. Subcellular partitioning profiles and metallothionein levels in indigenous clams Moerella iridescens from a metal-impacted coastal bay

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zaosheng, E-mail: zswang@iue.ac.cn [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Boulevard, Xiamen 361021 (China); State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Feng, Chenglian; Ye, Chun [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Wang, Youshao [State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301 (China); Yan, Changzhou, E-mail: czyan@iue.ac.cn [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Boulevard, Xiamen 361021 (China); Li, Rui; Yan, Yijun; Chi, Qiaoqiao [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Boulevard, Xiamen 361021 (China)

    2016-07-15

    Highlights: • Subcellular partitioning profile of metals were investigated in biomonitor organism. • Cu, Zn and Cd levels in main fraction of HSP increase along accumulation gradients. • Despite MTs as the major binding pool, detoxification of Cd and Pb was incomplete. • Induced MTs were sequentially correlated with Cu, Zn and Cd levels in HSP fraction. • Intracellular metal fates highlighted the metabolic availability within organism. - Abstract: In this study, the effect of environmental metal exposure on the accumulation and subcellular distribution of metals in the digestive gland of clams with special emphasis on metallothioneins (MTs) was investigated. Specimens of indigenous Moerella iridescens were collected from different natural habitats in Maluan Bay (China), characterized by varying levels of metal contamination. The digestive glands were excised, homogenized and six subcellular fractions were separated by differential centrifugation procedures and analyzed for their Cu, Zn, Cd and Pb contents. MTs were quantified independently by spectrophotometric measurements of thiols. Site-specific differences were observed in total metal concentrations in the tissues, correlating well with variable environmental metal concentrations and reflecting the gradient trends in metal contamination. Concentrations of the non-essential Cd and Pb were more responsive to environmental exposure gradients than were tissue concentrations of the essential metals, Cu and Zn. Subcellular partitioning profiles for Cu, Zn and Cd were relatively similar, with the heat-stable protein (HSP) fraction as the dominant metal-binding compartment, whereas for Pb this fraction was much less important. The variations in proportions and concentrations of metals in this fraction along with the metal bioaccumulation gradients suggested that the induced MTs play an important role in metal homeostasis and detoxification for M. iridescens in the metal-contaminated bay. Nevertheless

  2. Postsynaptic density protein 95 in the striosome and matrix compartments of the human neostriatum.

    Directory of Open Access Journals (Sweden)

    Ryoma eMorigaki

    2015-11-01

    Full Text Available The human neostriatum consists of two functional subdivisions referred to as the striosome (patch and matrix compartments. The striosome-matrix dopamine systems play a central role in cortico-thalamo-basal ganglia circuits, and their involvement is thought to underlie the genesis of multiple movement and behavioral disorders, and of drug addiction. Human neuropathology also has shown that striosomes and matrix have differential vulnerability patterns in several striatal neurodegenerative diseases. Postsynaptic density protein 95 (PSD-95, also known as DLG4, is a major scaffolding protein in the postsynaptic densities of dendritic spines. PSD-95 is now known to negatively regulate not only N-methyl-D-aspartate glutamate signaling, but also dopamine D1 signals at sites of postsynaptic transmission. Accordingly, a neuroprotective role for PSD-95 against dopamine D1 receptor (D1R-mediated neurotoxicity in striatal neurodegeneration also has been suggested. Here, we used a highly sensitive immunohistochemistry technique to show that in the human neostriatum, PSD-95 is differentially concentrated in the striosome and matrix compartments, with a higher density of PSD-95 labeling in the matrix compartment than in the striosomes. This compartment-specific distribution of PSD-95 was strikingly complementary to that of D1R. In addition to the possible involvement of PSD-95-mediated synaptic function in compartment-specific dopamine signals, we suggest that the striosomes might be more susceptible to D1R-mediated neurotoxicity than the matrix compartment. This notion may provide new insight into the compartment-specific vulnerability of MSNs in striatal neurodegeneration.

  3. Biomechanics of subcellular structures by non-invasive Brillouin microscopy

    Science.gov (United States)

    Antonacci, Giuseppe; Braakman, Sietse

    2016-11-01

    Cellular biomechanics play a pivotal role in the pathophysiology of several diseases. Unfortunately, current methods to measure biomechanical properties are invasive and mostly limited to the surface of a cell. As a result, the mechanical behaviour of subcellular structures and organelles remains poorly characterised. Here, we show three-dimensional biomechanical images of single cells obtained with non-invasive, non-destructive Brillouin microscopy with an unprecedented spatial resolution. Our results quantify the longitudinal elastic modulus of subcellular structures. In particular, we found the nucleoli to be stiffer than both the nuclear envelope (p biomechanics and its role in pathophysiology.

  4. Challenges of biological sample preparation for SIMS imaging of elements and molecules at subcellular resolution

    Science.gov (United States)

    Chandra, Subhash

    2008-12-01

    Secondary ion mass spectrometry (SIMS) based imaging techniques capable of subcellular resolution characterization of elements and molecules are becoming valuable tools in many areas of biology and medicine. Due to high vacuum requirements of SIMS, the live cells cannot be analyzed directly in the instrument. The sample preparation, therefore, plays a critical role in preserving the native chemical composition for SIMS analysis. This work focuses on the evaluation of frozen-hydrated and frozen freeze-dried sample preparations for SIMS studies of cultured cells with a CAMECA IMS-3f dynamic SIMS ion microscope instrument capable of producing SIMS images with a spatial resolution of 500 nm. The sandwich freeze-fracture method was used for fracturing the cells. The complimentary fracture planes in the plasma membrane were characterized by field-emission secondary electron microscopy (FESEM) in the frozen-hydrated state. The cells fractured at the dorsal surface were used for SIMS analysis. The frozen-hydrated SIMS analysis of individual cells under dynamic primary ion beam (O 2+) revealed local secondary ion signal enhancements correlated with the water image signals of 19(H 3O) +. A preferential removal of water from the frozen cell matrix in the Z-axis was also observed. These complications render the frozen-hydrated sample type less desirable for subcellular dynamic SIMS studies. The freeze-drying of frozen-hydrated cells, either inside the instrument or externally in a freeze-drier, allowed SIMS imaging of subcellular chemical composition. Morphological evaluations of fractured freeze-dried cells with SEM and confocal laser scanning microscopy (CLSM) revealed well-preserved mitochondria, Golgi apparatus, and stress fibers. SIMS analysis of fractured freeze-dried cells revealed well-preserved chemical composition of even the most highly diffusible ions like K + and Na + in physiologically relevant concentrations. The high K-low Na signature in individual cells

  5. Challenges of biological sample preparation for SIMS imaging of elements and molecules at subcellular resolution

    Energy Technology Data Exchange (ETDEWEB)

    Chandra, Subhash [Cornell SIMS Laboratory, Department of Earth and Atmospheric Sciences, Snee Hall, Cornell University, Ithaca, NY 14853 (United States)], E-mail: sc40@cornell.edu

    2008-12-15

    Secondary ion mass spectrometry (SIMS) based imaging techniques capable of subcellular resolution characterization of elements and molecules are becoming valuable tools in many areas of biology and medicine. Due to high vacuum requirements of SIMS, the live cells cannot be analyzed directly in the instrument. The sample preparation, therefore, plays a critical role in preserving the native chemical composition for SIMS analysis. This work focuses on the evaluation of frozen-hydrated and frozen freeze-dried sample preparations for SIMS studies of cultured cells with a CAMECA IMS-3f dynamic SIMS ion microscope instrument capable of producing SIMS images with a spatial resolution of 500 nm. The sandwich freeze-fracture method was used for fracturing the cells. The complimentary fracture planes in the plasma membrane were characterized by field-emission secondary electron microscopy (FESEM) in the frozen-hydrated state. The cells fractured at the dorsal surface were used for SIMS analysis. The frozen-hydrated SIMS analysis of individual cells under dynamic primary ion beam (O{sub 2}{sup +}) revealed local secondary ion signal enhancements correlated with the water image signals of {sup 19}(H{sub 3}O){sup +}. A preferential removal of water from the frozen cell matrix in the Z-axis was also observed. These complications render the frozen-hydrated sample type less desirable for subcellular dynamic SIMS studies. The freeze-drying of frozen-hydrated cells, either inside the instrument or externally in a freeze-drier, allowed SIMS imaging of subcellular chemical composition. Morphological evaluations of fractured freeze-dried cells with SEM and confocal laser scanning microscopy (CLSM) revealed well-preserved mitochondria, Golgi apparatus, and stress fibers. SIMS analysis of fractured freeze-dried cells revealed well-preserved chemical composition of even the most highly diffusible ions like K{sup +} and Na{sup +} in physiologically relevant concentrations. The high K

  6. Compartment syndrome in infants and toddlers.

    Science.gov (United States)

    Broom, Alexander; Schur, Mathew D; Arkader, Alexandre; Flynn, John; Gornitzky, Alex; Choi, Paul D

    2016-10-01

    To study the cause, diagnosis, treatment and outcome of acute compartment syndrome in infants and toddlers aged compartment syndrome were identified from two large pediatric trauma centers over a fifteen-year period. All children underwent fasciotomy. The mechanism of injury, time of injury, time to diagnosis, compartment pressures, time to fasciotomy, and outcome at the time of the latest follow-up were recorded. Nine (60 %) of fifteen patients developed compartment syndrome secondary to trauma, four (4/15, 27 %) due to infection, and two (2/15, 13 %) due to intravenous infiltration. The average time from injury or hospital admission to fasciotomy was 31.8 h (range 2.9-136.3 h). In general, the functional outcome was excellent at the latest follow-up with thirteen (13/15, 87 %) patients having an excellent outcome. No cases of Volkmann's ischemia were noted at the time of fasciotomy, even when performed as late as 5 days after injury. Compared to the general pediatric population, the diagnosis of compartment syndrome in infants and toddlers may be further delayed, i.e., >24 h after injury. Despite delays in diagnosis and time to treatment, the present study shows that outcomes in infants and toddlers remain favorable even when fasciotomy is performed 48-72 h after injury. Case series, level IV.

  7. Apical endocytosis in rat hepatocytes In situ involves clathrin, traverses a subapical compartment, and leads to lysosomes.

    Science.gov (United States)

    Rahner, C; Stieger, B; Landmann, L

    2000-12-01

    This study demonstrates and characterizes apical (canalicular) endocytic pathways in hepatocytes in situ. Endocytic markers were administered by retrograde infusion through the common bile duct. Colocalization with proteins that are specific for various endocytic compartments was performed on stacks of deconvoluted confocal immunofluorescence images. The subcellular distribution of marker proteins was assessed by electron microscopy (EM). Bulk-phase, as well as membrane-associated markers, were internalized readily at the apical cell pole. At the EM level, marker was found initially in 60-100-nm tubulovesicular structures and 150-200-nm cup-shaped vesicles, whereas multivesicular bodies and lysosomes became labeled after longer time intervals. Apical endocytosis involved clathrin and delivered marker to late endosomes (rab7(+), cathepsin D(+)), as well as lysosomes (rab7(-), cathepsin D(+)). Simultaneous labeling of the basolateral endocytic route resulted in overlap of both pathways in the late endosomal and lysosomal compartments. In addition, apical endocytosis involved a subapical compartment (endolyn-78(+), rab11(+), polymeric IgA receptor [pIgA-R(+)]) that is passed by the transcytotic route, thus constituting a crossroads. pIgA-R immunoreactivity, probably reflecting the cleaved receptor fragment, was associated with apical endocytic marker and colocalized with clathrin and later with cathepsin D. Apical endocytosis involves coated pits/vesicles, leads to a subapical compartment, and plays a role in the retrieval of canalicular plasma membrane components for lysosomal degradation.

  8. Cutaneous anthrax cases leading compartment syndrome

    Directory of Open Access Journals (Sweden)

    Emine Parlak

    2013-12-01

    Full Text Available Bacillus anthracis is the causative agent of anthrax. Anthrax is a zoonotic disease with three clinical forms. Clinical forms are skin, gastrointestinal and inhalational anthrax. Cutaneous anthrax is 95% of the cases. Cutaneous anthrax frequently defines itself. Clinical presentation of anthrax may be severe and complicated in some cases. There may seem complications like meningitis, septic shock and compartment syndrome. Compartment Syndrome is a rare complication of cutaneous anthrax and it is life threatening. Physicians working in the endemic area should be aware of this form. In this study, three cases were shown which developed compartment syndrome following cutaneous anthrax. J Microbiol Infect Dis 2013;3(4: 214-217

  9. Expression pattern, subcellular localization, and functional implications of ODAM in ameloblasts, odontoblasts, osteoblasts, and various cancer cells.

    Science.gov (United States)

    Lee, Hye-Kyung; Park, Su-Jin; Oh, Hyun-Jung; Kim, Jung-Wook; Bae, Hyun-Sook; Park, Joo-Cheol

    2012-01-01

    During tooth development and tumorigenesis, the odontogenic ameloblast-associated protein (ODAM) is involved in cellular differentiation and matrix protein production. However, the precise function of ODAM remains largely unknown. To suggest new functional roles of ODAM, we investigated the cellular expression and subcellular localization of ODAM in tooth and cancer cells. ODAM was expressed in ameloblasts, odontoblasts, and osteoblasts in vivo and in vitro. Furthermore, ODAM was localized in both the nucleus and cytoplasm of MMP-20 expressing ameloblasts and odontoblasts, but only in the cytoplasm of non-MMP-20 expressing osteoblasts. The extracellular secretion of ODAM was not observed in odontoblasts and osteoblasts, but was seen in ameloblasts. In addition, ODAM was discovered in the nucleus, cytoplasm, and extracellular matrix of various cancer cells. These results suggest that the expression pattern and subcellular localization of ODAM is highly variable and dependent on cell types and their differentiation states, and that functional correlations exist between ODAM and MMP-20. This study provides the first evidence for ODAM in multiple cellular compartments of differentiating odontogenic and cancer cell lines with important functional implications. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Regulation of the Regulators: Post-Translational Modifications, Subcellular, and Spatiotemporal Distribution of Plant 14-3-3 Proteins.

    Science.gov (United States)

    Wilson, Rashaun S; Swatek, Kirby N; Thelen, Jay J

    2016-01-01

    14-3-3 proteins bind to and modulate the activity of phosphorylated proteins that regulate a variety of metabolic processes in eukaryotes. Multiple 14-3-3 isoforms are expressed in most organisms and display redundancy in both sequence and function. Plants contain the largest number of 14-3-3 isoforms. For example, Arabidopsis thaliana contains thirteen 14-3-3 genes, each of which is expressed. Interest in the plant 14-3-3 field has swelled over the past decade, largely due to the vast number of possibilities for 14-3-3 metabolic regulation. As the field progresses, it is essential to understand these proteins' activities at both the spatiotemporal and subcellular levels. This review summarizes current knowledge of 14-3-3 proteins in plants, including 14-3-3 interactions, regulatory functions, isoform specificity, and post-translational modifications. We begin with a historical overview and structural analysis of 14-3-3 proteins, which describes the basic principles of 14-3-3 function, and then discuss interactions and regulatory effects of plant 14-3-3 proteins in specific tissues and subcellular compartments. We conclude with a summary of 14-3-3 phosphorylation and current knowledge of the functional effects of this modification in plants.

  11. Weak mitochondrial targeting sequence determines tissue-specific subcellular localization of glutamine synthetase in liver and brain cells.

    Science.gov (United States)

    Matthews, Gideon D; Gur, Noa; Koopman, Werner J H; Pines, Ophry; Vardimon, Lily

    2010-02-01

    Evolution of the uricotelic system for ammonia detoxification required a mechanism for tissue-specific subcellular localization of glutamine synthetase (GS). In uricotelic vertebrates, GS is mitochondrial in liver cells and cytoplasmic in brain. Because these species contain a single copy of the GS gene, it is not clear how tissue-specific subcellular localization is achieved. Here we show that in chicken, which utilizes the uricotelic system, the GS transcripts of liver and brain cells are identical and, consistently, there is no difference in the amino acid sequence of the protein. The N-terminus of GS, which constitutes a 'weak' mitochondrial targeting signal (MTS), is sufficient to direct a chimeric protein to the mitochondria in hepatocytes and to the cytoplasm in astrocytes. Considering that a weak MTS is dependent on a highly negative mitochondrial membrane potential (DeltaPsi) for import, we examined the magnitude of DeltaPsi in hepatocytes and astrocytes. Our results unexpectedly revealed that DeltaPsi in hepatocytes is considerably more negative than that of astrocytes and that converting the targeting signal into 'strong' MTS abolished the capability to confer tissue-specific subcellular localization. We suggest that evolutional selection of weak MTS provided a tool for differential targeting of an identical protein by taking advantage of tissue-specific differences in DeltaPsi.

  12. Space Shuttle crew compartment debris-contamination

    Science.gov (United States)

    Goodman, Jerry R.; Villarreal, Leopoldo J.

    1992-01-01

    Remedial actions undertaken to reduce debris during manned flights and ground turnaround operations at Kennedy Space Center and Palmdale are addressed. They include redesign of selected ground support equipment and Orbiter hardware to reduce particularization/debris generation; development of new detachable filters for air-cooled avionics boxes; application of tape-on screens to filter debris; and implementation of new Orbiter maintenance and turnaround procedures to clean filters and the crew compartment. Most of these steps were implemented before the return-to-flight of STS-26 in September 1988 which resulted in improved crew compartment habitability and less potential for equipment malfunction.

  13. Forearm compartment syndrome secondary to leukemic infiltrates.

    Science.gov (United States)

    Trumble, T

    1987-07-01

    A 20-year-old white man with leukemia was recently treated with chemotherapy and was admitted to the Massachusetts General Hospital with a fever and a swollen and painful left forearm that worsened despite intravenous antibiotics. The flexor forearm compartment pressures were elevated; therefore, surgical decompression of the flexor compartments was done. All the wound cultures were negative, and biopsy specimens of tissue showed leukemic infiltrates in the muscle and subcutaneous tissue. Tumor infiltrates may result in increased compartmental pressures, and the treatment of these lesions includes chemotherapy and/or radiation therapy to provide local control of the tumor.

  14. Characterization of NAADP-mediated calcium signaling in human spermatozoa

    Energy Technology Data Exchange (ETDEWEB)

    Sánchez-Tusie, A.A. [Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos (Mexico); Vasudevan, S.R.; Churchill, G.C. [Department of Pharmacology, University of Oxford, Oxford OX1 3QT, England (United Kingdom); Nishigaki, T. [Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos (Mexico); Treviño, C.L., E-mail: ctrevino@ibt.unam.mx [Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos (Mexico)

    2014-01-10

    Highlights: •Human sperm cells synthesize NAADP. •NAADP-AM mediates [Ca{sup 2+}]{sub i} increases in human sperm in the absence of [Ca{sup 2+}]{sub o}. •Human sperm have two acidic compartments located in the head and midpiece. -- Abstract: Ca{sup 2+} signaling in spermatozoa plays a crucial role during processes such as capacitation and release of the acrosome, but the underlying molecular mechanisms still remain unclear. Nicotinic acid adenine dinucleotide phosphate (NAADP) is a potent Ca{sup 2+}-releasing second messenger in a variety of cellular processes. The presence of a NAADP synthesizing enzyme in sea urchin sperm has been previously reported, suggesting a possible role of NAADP in sperm Ca{sup 2+} signaling. In this work we used in vitro enzyme assays to show the presence of a novel NAADP synthesizing enzyme in human sperm, and to characterize its sensitivity to Ca{sup 2+} and pH. Ca{sup 2+} fluorescence imaging studies demonstrated that the permeable form of NAADP (NAADP-AM) induces intracellular [Ca{sup 2+}] increases in human sperm even in the absence of extracellular Ca{sup 2+}. Using LysoTracker®, a fluorescent probe that selectively accumulates in acidic compartments, we identified two such stores in human sperm cells. Their acidic nature was further confirmed by the reduction in staining intensity observed upon inhibition of the endo-lysosomal proton pump with Bafilomycin, or after lysosomal bursting with glycyl-L-phenylalanine-2-naphthylamide. The selective fluorescent NAADP analog, Ned-19, stained the same subcellular regions as LysoTracker®, suggesting that these stores are the targets of NAADP action.

  15. Protein Subcellular Relocalization of Duplicated Genes in Arabidopsis

    Science.gov (United States)

    Liu, Shao-Lun; Pan, An Qi; Adams, Keith L.

    2014-01-01

    Gene duplications during eukaroytic evolution, by successive rounds of polyploidy and by smaller scale duplications, have provided an enormous reservoir of new genes for the evolution of new functions. Preservation of many duplicated genes can be ascribed to changes in sequences, expression patterns, and functions. Protein subcellular relocalization (protein targeting to a new location within the cell) is another way that duplicated genes can diverge. We studied subcellular relocalization of gene pairs duplicated during the evolution of the Brassicaceae including gene pairs from the alpha whole genome duplication that occurred at the base of the family. We analyzed experimental localization data from green fluorescent protein experiments for 128 duplicate pairs in Arabidopsis thaliana, revealing 19 pairs with subcellular relocalization. Many more of the duplicate pairs with relocalization than with the same localization showed an accelerated rate of amino acid sequence evolution in one duplicate, and one gene showed evidence for positive selection. We studied six duplicate gene pairs in more detail. We used gene family analysis with several pairs to infer which gene shows relocalization. We identified potential sequence mutations through comparative analysis that likely result in relocalization of two duplicated gene products. We show that four cases of relocalization have new expression patterns, compared with orthologs in outgroup species, including two with novel expression in pollen. This study provides insights into subcellular relocalization of evolutionarily recent gene duplicates and features of genes whose products have been relocalized. PMID:25193306

  16. [Anti-tumor immunity of Newcastle disease virus HN protein is influenced by differential subcellular targeting].

    Science.gov (United States)

    Wang, Kaibing; Sui, Hong; Li, Lejing; Li, Xi; Wang, Lei

    2010-08-01

    Hemagglutinin-neuraminidase (HN) protein of newcastle disease virus is an important immunogen for oncolysis. We designed three different expression plasmids encoding the HN protein targeted to different subcellular compartments: cytoplasmic (Cy-HN), secreted (Sc-HN) and membrane-anchored (M-HN). On the basis of antitumor effect in vitro, the aim of this study is to investigate the anti-tumor immunity effect of HN protein in vivo. In the present study, we developed a mouse model in order to evaluate the anti-tumor effect of the intratumorally injected modified HN proteins and the anti-tumor immunity by lymphocyte proliferative response and CTL activity test. Although all three DNA constructs elicited an immune response, tumor-bearing mice intratumorally injected with M-HN demonstrated a significantly better anti-tumor effect than those injected with Cy-HN or Sc-HN (Day 18: P=0.022; Day 21: Psubcellular targeting. The membrane-anchored form of the HN protein appears to be an ideal candidate to improve the specific cellular immunity.

  17. Arabinogalactan Glycosyltransferases: Enzyme Assay, Protein-Protein Interaction, Subcellular Localization, and Perspectives for Application

    Directory of Open Access Journals (Sweden)

    Naomi Geshi

    2014-01-01

    Full Text Available Arabinogalactan proteins (AGPs are abundant extracellular proteoglycans that are found in most plant species and involved in many cellular processes, such as cell proliferation and survival, pattern formation, and growth, and in plant microbe interaction. AGPs are synthesized by posttranslational O-glycosylation of proteins and attached glycan part often constitutes greater than 90% of the molecule. Subtle altered glycan structures during development have been considered to function as developmental markers on the cell surface, but little is known concerning the molecular mechanisms. My group has been working on glycosylation enzymes (glycosyltransferases of AGPs to investigate glycan function of the molecule. This review summarizes the recent findings from my group as for AtGalT31A, AtGlcAT14A-C, and AtGalT29A of Arabidopsis thaliana with a specific focus on the (i biochemical enzyme activities; (ii subcellular compartments targeted by the glycosyltransferases; and (iii protein-protein interactions. I also discuss application aspect of glycosyltransferase in improving AGP-based product used in industry, for example, gum arabic.

  18. Arginine methylation controls the subcellular localization and functions of the oncoprotein splicing factor SF2/ASF.

    Science.gov (United States)

    Sinha, Rahul; Allemand, Eric; Zhang, Zuo; Karni, Rotem; Myers, Michael P; Krainer, Adrian R

    2010-06-01

    Alternative splicing and posttranslational modifications (PTMs) are major sources of protein diversity in eukaryotic proteomes. The SR protein SF2/ASF is an oncoprotein that functions in pre-mRNA splicing, with additional roles in other posttranscriptional and translational events. Functional studies of SR protein PTMs have focused exclusively on the reversible phosphorylation of Ser residues in the C-terminal RS domain. We confirmed that human SF2/ASF is methylated at residues R93, R97, and R109, which were identified in a global proteomic analysis of Arg methylation, and further investigated whether these methylated residues regulate the properties of SF2/ASF. We show that the three arginines additively control the subcellular localization of SF2/ASF and that both the positive charge and the methylation state are important. Mutations that block methylation and remove the positive charge result in the cytoplasmic accumulation of SF2/ASF. The consequent decrease in nuclear SF2/ASF levels prevents it from modulating the alternative splicing of target genes, results in higher translation stimulation, and abrogates the enhancement of nonsense-mediated mRNA decay. This study addresses the mechanisms by which Arg methylation and the associated positive charge regulate the activities of SF2/ASF and emphasizes the significance of localization control for an oncoprotein with multiple functions in different cellular compartments.

  19. Proteomic Analysis of Lysine Acetylation Sites in Rat Tissues Reveals Organ Specificity and Subcellular Patterns

    Directory of Open Access Journals (Sweden)

    Alicia Lundby

    2012-08-01

    Full Text Available Lysine acetylation is a major posttranslational modification involved in a broad array of physiological functions. Here, we provide an organ-wide map of lysine acetylation sites from 16 rat tissues analyzed by high-resolution tandem mass spectrometry. We quantify 15,474 modification sites on 4,541 proteins and provide the data set as a web-based database. We demonstrate that lysine acetylation displays site-specific sequence motifs that diverge between cellular compartments, with a significant fraction of nuclear sites conforming to the consensus motifs G-AcK and AcK-P. Our data set reveals that the subcellular acetylation distribution is tissue-type dependent and that acetylation targets tissue-specific pathways involved in fundamental physiological processes. We compare lysine acetylation patterns for rat as well as human skeletal muscle biopsies and demonstrate its general involvement in muscle contraction. Furthermore, we illustrate that acetylation of fructose-bisphosphate aldolase and glycerol-3-phosphate dehydrogenase serves as a cellular mechanism to switch off enzymatic activity.

  20. Subcellular clearance and accumulation of Huntington disease protein: A mini-review

    Directory of Open Access Journals (Sweden)

    Ting eZhao

    2016-04-01

    Full Text Available Huntington’s disease (HD is an autosomal dominant, progressive neurodegenerative disease caused by an expanded polyglutamine (polyQ tract in the N-terminal region of mutant huntingtin (mHtt. As a result, mHtt forms aggregates that are abundant in the nuclei and processes of neuronal cells. Although the roles of mHtt aggregates are still debated, the formation of aggregates points to deficient clearance of mHtt in brain cells. Since the accumulation of mHtt is a prerequisite for its neurotoxicity, exploring the mechanisms for mHtt accumulation and clearance would advance our understanding of HD pathogenesis and help us develop treatments for HD. We know that the ubiquitin-proteasome system and autophagy play important roles in clearing mHtt; however, how mHtt preferentially accumulates in neuronal nuclei and processes remains unclear. Studying the clearance of mHtt in neuronal cells is a challenge because neurons are morphologically and functionally polarized, which means the turnover of mHtt may be distinct in different cellular compartments. In this review, we discuss our current knowledge about the clearance and accumulation of mHtt and strategies of examining mHtt clearance and accumulation in different subcellular regions

  1. Subcellular localization of Arabidopsis arogenate dehydratases suggests novel and non-enzymatic roles

    Science.gov (United States)

    Bross, Crystal D.; Howes, Travis R.; Abolhassani Rad, Sara; Kljakic, Ornela

    2017-01-01

    Abstract Arogenate dehydratases (ADTs) catalyze the final step in phenylalanine biosynthesis in plants. The Arabidopsis thaliana genome encodes a family of six ADTs capable of decarboxylating/dehydrating arogenate into phenylalanine. Using cyan fluorescent protein (CFP)-tagged proteins, the subcellular localization patterns of all six A. thaliana ADTs were investigated in intact Nicotiana benthamiana and A. thaliana leaf cells. We show that A. thaliana ADTs localize to stroma and stromules (stroma-filled tubules) of chloroplasts. This localization pattern is consistent with the enzymatic function of ADTs as many enzymes required for amino acid biosynthesis are primarily localized to chloroplasts, and stromules are thought to increase metabolite transport from chloroplasts to other cellular compartments. Furthermore, we provide evidence that ADTs have additional, non-enzymatic roles. ADT2 localizes in a ring around the equatorial plane of chloroplasts or to a chloroplast pole, which suggests that ADT2 is a component of the chloroplast division machinery. In addition to chloroplasts, ADT5 was also found in nuclei, again suggesting a non-enzymatic role for ADT5. We also show evidence that ADT5 is transported to the nucleus via stromules. We propose that ADT2 and ADT5 are moonlighting proteins that play an enzymatic role in phenylalanine biosynthesis and a second role in chloroplast division or transcriptional regulation, respectively. PMID:28338876

  2. Single-Molecule Narrow-Field Microscopy of Protein-DNA Binding Dynamics in Glucose Signal Transduction of Live Yeast Cells.

    Science.gov (United States)

    Wollman, Adam J M; Leake, Mark C

    2016-01-01

    Single-molecule narrow-field microscopy is a versatile tool to investigate a diverse range of protein dynamics in live cells and has been extensively used in bacteria. Here, we describe how these methods can be extended to larger eukaryotic, yeast cells, which contain subcellular compartments. We describe how to obtain single-molecule microscopy data but also how to analyze these data to track and obtain the stoichiometry of molecular complexes diffusing in the cell. We chose glucose mediated signal transduction of live yeast cells as the system to demonstrate these single-molecule techniques as transcriptional regulation is fundamentally a single-molecule problem-a single repressor protein binding a single binding site in the genome can dramatically alter behavior at the whole cell and population level.

  3. Editorial: Acute compartment syndrome | Gakuu | East African ...

    African Journals Online (AJOL)

    East African Orthopaedic Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 8, No 2 (2014) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. Editorial: Acute compartment syndrome. LN Gakuu. Abstract. No abstract.

  4. Osteotomy induced compartment syndrome: A case Report ...

    African Journals Online (AJOL)

    Acute Compartment Syndrome (ACS) is a known potential complication of trauma and surgery of the leg. Although routine intracompartment pressure monitoring may prevent many cases, a high index of suspicion and aggressive preventive measures are the mainstay of management especially in high-risk patients. In spite ...

  5. 14 CFR 29.853 - Compartment interiors.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Compartment interiors. 29.853 Section 29.853 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... in a common housing, seat belts, shoulder harnesses, and cargo and baggage tiedown equipment...

  6. Gluteal Compartment Syndrome Secondary to Pelvic Trauma

    Directory of Open Access Journals (Sweden)

    Fernando Diaz Dilernia

    2016-01-01

    Full Text Available Gluteal compartment syndrome (GCS is extremely rare when compared to compartment syndrome in other anatomical regions, such as the forearm or the lower leg. It usually occurs in drug users following prolonged immobilization due to loss of consciousness. Another possible cause is trauma, which is rare and has only few reports in the literature. Physical examination may show tense and swollen buttocks and severe pain caused by passive range of motion. We present the case of a 70-year-old man who developed GCS after prolonged anterior-posterior pelvis compression. The physical examination revealed swelling, scrotal hematoma, and left ankle extension weakness. An unstable pelvic ring injury was diagnosed and the patient was taken to surgery. Measurement of the intracompartmental pressure was measured in the operating room, thereby confirming the diagnosis. Emergent fasciotomy was performed to decompress the three affected compartments. Trauma surgeons must be aware of the possibility of gluteal compartment syndrome in patients who have an acute pelvic trauma with buttock swelling and excessive pain of the gluteal region. Any delay in diagnosis or treatment can be devastating, causing permanent disability, irreversible loss of gluteal muscles, sciatic nerve palsy, kidney failure, or even death.

  7. Volkmann's Ischaemic Contracture following acute compartment ...

    African Journals Online (AJOL)

    Setting: PCEA Kikuyu hospital. Methods: An eight year old boy was treated and followed up after he had suffered compartment syndrome on his left forearm. This occurred after he fell and sustained fractures of both radius and ulnar. He was put in a cast at a peripheral hospital. East African Orthopaedic Journal, Vol.

  8. Management of chronic exertional compartment syndrome | Islam ...

    African Journals Online (AJOL)

    South African Journal of Surgery ... Methods: A total of 123 patients with extremity muscle pain, swelling and paraesthesia during the last 10 years were evaluated from a prospective database with compartment pressures ... Open fasciotomy is safe and effective and should be considered as the preferred surgical procedure.

  9. Abdominal Compartment Syndrome in Surgical Patients | Muturi ...

    African Journals Online (AJOL)

    Background: The deleterious effects of intraabdominal hypertension and abdominal compartment syndrome, affect almost every system. Patients at risk are the critically ill, in whom it leads to alteredorgan perfusion and end organ dysfunction/failure. The five cases reported highlight the diagnostic and management ...

  10. Cell-specific STORM superresolution imaging reveals nanoscale organization of cannabinoid signaling

    Science.gov (United States)

    Szabó, Szilárd I.; Szabadits, Eszter; Pintér, Balázs; Woodhams, Stephen G.; Henstridge, Christopher M.; Balla, Gyula Y.; Nyilas, Rita; Varga, Csaba; Lee, Sang-Hun; Matolcsi, Máté; Cervenak, Judit; Kacskovics, Imre; Watanabe, Masahiko; Sagheddu, Claudia; Melis, Miriam; Pistis, Marco; Soltesz, Ivan; Katona, István

    2014-01-01

    A major challenge in neuroscience is to determine the nanoscale position and quantity of signaling molecules in a cell-type-, and subcellular compartment-specific manner. We therefore developed a novel approach combining cell-specific physiological and anatomical characterization with superresolution imaging, and studied the molecular and structural parameters shaping the physiological properties of synaptic endocannabinoid signaling in the mouse hippocampus. We found that axon terminals of perisomatically-projecting GABAergic interneurons possess increased CB1 receptor number, active-zone complexity, and receptor/effector ratio compared to dendritically-projecting interneurons, in agreement with higher efficiency of cannabinoid signaling at somatic versus dendritic synapses. Furthermore, chronic Δ9-tetrahydrocannabinol administration, which reduces cannabinoid efficacy on GABA release, evoked dramatic CB1-downregulation in a dose-dependent manner. Full receptor recovery required several weeks after cessation of Δ9-tetrahydrocannabinol treatment. These findings demonstrate that cell-type-specific nanoscale analysis of endogenous protein distribution is possible in brain circuits, and identify novel molecular properties controlling endocannabinoid signaling and cannabis-induced cognitive dysfunction. PMID:25485758

  11. Subcellular targeting of nine calcium-dependent protein kinase isoforms from Arabidopsis

    Science.gov (United States)

    Dammann, Christian; Ichida, Audrey; Hong, Bimei; Romanowsky, Shawn M.; Hrabak, Estelle M.; Harmon, Alice C.; Pickard, Barbara G.; Harper, Jeffrey F.; Evans, M. L. (Principal Investigator)

    2003-01-01

    Calcium-dependent protein kinases (CDPKs) are specific to plants and some protists. Their activation by calcium makes them important switches for the transduction of intracellular calcium signals. Here, we identify the subcellular targeting potentials for nine CDPK isoforms from Arabidopsis, as determined by expression of green fluorescent protein (GFP) fusions in transgenic plants. Subcellular locations were determined by fluorescence microscopy in cells near the root tip. Isoforms AtCPK3-GFP and AtCPK4-GFP showed a nuclear and cytosolic distribution similar to that of free GFP. Membrane fractionation experiments confirmed that these isoforms were primarily soluble. A membrane association was observed for AtCPKs 1, 7, 8, 9, 16, 21, and 28, based on imaging and membrane fractionation experiments. This correlates with the presence of potential N-terminal acylation sites, consistent with acylation as an important factor in membrane association. All but one of the membrane-associated isoforms targeted exclusively to the plasma membrane. The exception was AtCPK1-GFP, which targeted to peroxisomes, as determined by covisualization with a peroxisome marker. Peroxisome targeting of AtCPK1-GFP was disrupted by a deletion of two potential N-terminal acylation sites. The observation of a peroxisome-located CDPK suggests a mechanism for calcium regulation of peroxisomal functions involved in oxidative stress and lipid metabolism.

  12. The Ubiquitous Distribution of Late Embryogenesis Abundant Proteins across Cell Compartments in Arabidopsis Offers Tailored Protection against Abiotic Stress[C][W][OPEN

    Science.gov (United States)

    Candat, Adrien; Paszkiewicz, Gaël; Neveu, Martine; Gautier, Romain; Logan, David C.; Avelange-Macherel, Marie-Hélène; Macherel, David

    2014-01-01

    Late embryogenesis abundant (LEA) proteins are hydrophilic, mostly intrinsically disordered proteins, which play major roles in desiccation tolerance. In Arabidopsis thaliana, 51 genes encoding LEA proteins clustered into nine families have been inventoried. To increase our understanding of the yet enigmatic functions of these gene families, we report the subcellular location of each protein. Experimental data highlight the limits of in silico predictions for analysis of subcellular localization. Thirty-six LEA proteins localized to the cytosol, with most being able to diffuse into the nucleus. Three proteins were exclusively localized in plastids or mitochondria, while two others were found dually targeted to these organelles. Targeting cleavage sites could be determined for five of these proteins. Three proteins were found to be endoplasmic reticulum (ER) residents, two were vacuolar, and two were secreted. A single protein was identified in pexophagosomes. While most LEA protein families have a unique subcellular localization, members of the LEA_4 family are widely distributed (cytosol, mitochondria, plastid, ER, and pexophagosome) but share the presence of the class A α-helix motif. They are thus expected to establish interactions with various cellular membranes under stress conditions. The broad subcellular distribution of LEA proteins highlights the requirement for each cellular compartment to be provided with protective mechanisms to cope with desiccation or cold stress. PMID:25005920

  13. Involvement of the mitochondrial compartment in human NCL fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Pezzini, Francesco; Gismondi, Floriana [Department of Neurological, Psychological, Morphological and Motor Sciences, Divisions of Neurology (Child Neurology) and Neuropathology, University of Verona Medical School, Verona (Italy); Tessa, Alessandra [IRCCS Fondazione Stella Maris-Molecular Medicine Unit, Pisa (Italy); Tonin, Paola [Department of Neurological, Psychological, Morphological and Motor Sciences, Divisions of Neurology (Child Neurology) and Neuropathology, University of Verona Medical School, Verona (Italy); Carrozzo, Rosalba [IRCCS Bambino Gesu Hospital-Molecular Medicine Unit, Roma (Italy); Mole, Sara E. [MRC Laboratory for Molecular Cell Biology, Molecular Medicines Unit, UCL Institute of Child Health and Department of Genetics, Evolution and Environment, University College London (United Kingdom); Santorelli, Filippo M. [IRCCS Fondazione Stella Maris-Molecular Medicine Unit, Pisa (Italy); Simonati, Alessandro, E-mail: alessandro.simonati@univr.it [Department of Neurological, Psychological, Morphological and Motor Sciences, Divisions of Neurology (Child Neurology) and Neuropathology, University of Verona Medical School, Verona (Italy)

    2011-12-09

    Highlights: Black-Right-Pointing-Pointer Mitochondrial reticulum fragmentation occurs in human CLN1 and CLN6 fibroblasts. Black-Right-Pointing-Pointer Likewise mitochondrial shift-to periphery and decreased mitochondrial density are seen. Black-Right-Pointing-Pointer Enhanced caspase-mediated apoptosis occurs following STS treatment in CLN1 fibroblasts. -- Abstract: Neuronal ceroid lipofuscinosis (NCL) are a group of progressive neurodegenerative disorders of childhood, characterized by the endo-lysosomal storage of autofluorescent material. Impaired mitochondrial function is often associated with neurodegeneration, possibly related to the apoptotic cascade. In this study we investigated the possible effects of lysosomal accumulation on the mitochondrial compartment in the fibroblasts of two NCL forms, CLN1 and CLN6. Fragmented mitochondrial reticulum was observed in all cells by using the intravital fluorescent marker Mitotracker, mainly in the perinuclear region. This was also associated with intense signal from the lysosomal markers Lysotracker and LAMP2. Likewise, mitochondria appeared to be reduced in number and shifted to the cell periphery by electron microscopy; moreover the mitochondrial markers VDCA and COX IV were reduced following quantitative Western blot analysis. Whilst there was no evidence of increased cell death under basal condition, we observed a significant increase in apoptotic nuclei following Staurosporine treatment in CLN1 cells only. In conclusion, the mitochondrial compartment is affected in NCL fibroblasts invitro, and CLN1 cells seem to be more vulnerable to the negative effects of stressed mitochondrial membrane than CLN6 cells.

  14. The 2013 German-Russian Bion-M1 Joint Flight Project: Altered cAMP/PKA Signaling Pathway in Skeletal Muscle during Exposure to Real Microgravity in Mice Housed for 30 Days in a Biosatellite on Orbit

    Science.gov (United States)

    Salanova, Michele; Blottner, Dieter; Shenkman, Boris S.; Lomonosova, Yulia

    Exposure to real microgravity (muG) results in an impaired skeletal muscle structure and function. We here hypothesized that the cAMP/PKA cell signaling pathway, which triggers a multitude of intracellular effects in response to a variety of extracellular stimuli and which further promote muscle growth, play an important role during Spaceflight- induced disuse atrophy. Particularly, we hypothesized that different effectors of the cAMP-PKA signaling machinery, which are highly compartmentalized into subcellular functional microdomains in order to guarantee signal specificity, are altered after long term exposure to real µG. Taking advantage of the Bion-M1 Spaceflight program which provided us an excellent opportunity to explore mice skeletal muscle exposed for 30 days to real µG, by investigating at the cAMP-dependent protein kinase A (PKA) subcellular localization we compared muscle soleus (SOL) and extensor digitorum longus (EDL) of C57/black mice of a Bion-flight (n=5) group with a Bion-ground control (n=5) group and a ground control (n=5) group which was housed in a standard cage considered as vivarium control. Preliminary results of our experiments showed that different cAMP-PKA micro pools were normally detectable using high-resolution images of immunofluorescence experiments in different subcellular compartments of both SOL and EDL of Bion-ground and ground control groups which were not any longer detectable in Bion-flight group. In summary, our data indicate that an efficient organization in microdomains of the cAMP/PKA pathway may exist in skeletal muscle on ground and that such compartmentalization may be altered in response to prolonged exposure to real muG. National Sponsors: Federal Ministry of Economics and Technology (BMWi) via the German AeroSpace Board, DLR e.V., Bonn-Oberkassel, Germany (#50WB1121 to DB); Contract RAS-IMPB/Charité Berlin # Bion-M1/2013

  15. GAP Activity, but Not Subcellular Targeting, Is Required for Arabidopsis RanGAP Cellular and Developmental Functions.

    Science.gov (United States)

    Boruc, Joanna; Griffis, Anna H N; Rodrigo-Peiris, Thushani; Zhou, Xiao; Tilford, Bailey; Van Damme, Daniël; Meier, Iris

    2015-07-01

    The Ran GTPase activating protein (RanGAP) is important to Ran signaling involved in nucleocytoplasmic transport, spindle organization, and postmitotic nuclear assembly. Unlike vertebrate and yeast RanGAP, plant RanGAP has an N-terminal WPP domain, required for nuclear envelope association and several mitotic locations of Arabidopsis thaliana RanGAP1. A double null mutant of the two Arabidopsis RanGAP homologs is gametophyte lethal. Here, we created a series of mutants with various reductions in RanGAP levels by combining a RanGAP1 null allele with different RanGAP2 alleles. As RanGAP level decreases, the severity of developmental phenotypes increases, but nuclear import is unaffected. To dissect whether the GAP activity and/or the subcellular localization of RanGAP are responsible for the observed phenotypes, this series of rangap mutants were transformed with RanGAP1 variants carrying point mutations abolishing the GAP activity and/or the WPP-dependent subcellular localization. The data show that plant development is differentially affected by RanGAP mutant allele combinations of increasing severity and requires the GAP activity of RanGAP, while the subcellular positioning of RanGAP is dispensable. In addition, our results indicate that nucleocytoplasmic trafficking can tolerate both partial depletion of RanGAP and delocalization of RanGAP from the nuclear envelope. © 2015 American Society of Plant Biologists. All rights reserved.

  16. Novel Application of Fluorescence Lifetime and Fluorescence Microscopy Enables Quantitative Access to Subcellular Dynamics in Plant Cells

    Science.gov (United States)

    Elgass, Kirstin; Caesar, Katharina; Schleifenbaum, Frank; Stierhof, York-Dieter; Meixner, Alfred J.; Harter, Klaus

    2009-01-01

    Background Optical and spectroscopic technologies working at subcellular resolution with quantitative output are required for a deeper understanding of molecular processes and mechanisms in living cells. Such technologies are prerequisite for the realisation of predictive biology at cellular and subcellular level. However, although established in the physical sciences, these techniques are rarely applied to cell biology in the plant sciences. Principal Findings Here, we present a combined application of one-chromophore fluorescence lifetime microscopy and wavelength-selective fluorescence microscopy to analyse the function of a GFP fusion of the Brassinosteroid Insensitive 1 Receptor (BRI1-GFP) with high spatial and temporal resolution in living Arabidopsis cells in their tissue environment. We show a rapid, brassinolide-induced cell wall expansion and a fast BR-regulated change in the BRI1-GFP fluorescence lifetime in the plasmamembrane in vivo. Both cell wall expansion and changes in fluorescence lifetime reflect early BR-induced and BRI1-dependent physiological or signalling processes. Our experiments also show the potential of one-chromophore fluorescence lifetime microscopy for the in vivo monitoring of the biochemical and biophysical subcellular environment using GFP fusion proteins as probes. Significance One-chromophore fluorescence lifetime microscopy, combined with wavelength-specific fluorescence microscopy, opens up new frontiers for in vivo dynamic and quantitative analysis of cellular processes at high resolution which are not addressable by pure imaging technologies or transmission electron microscopy. PMID:19492078

  17. Imaging trace element distributions in single organelles and subcellular features

    Science.gov (United States)

    Kashiv, Yoav; Austin, Jotham R.; Lai, Barry; Rose, Volker; Vogt, Stefan; El-Muayed, Malek

    2016-02-01

    The distributions of chemical elements within cells are of prime importance in a wide range of basic and applied biochemical research. An example is the role of the subcellular Zn distribution in Zn homeostasis in insulin producing pancreatic beta cells and the development of type 2 diabetes mellitus. We combined transmission electron microscopy with micro- and nano-synchrotron X-ray fluorescence to image unequivocally for the first time, to the best of our knowledge, the natural elemental distributions, including those of trace elements, in single organelles and other subcellular features. Detected elements include Cl, K, Ca, Co, Ni, Cu, Zn and Cd (which some cells were supplemented with). Cell samples were prepared by a technique that minimally affects the natural elemental concentrations and distributions, and without using fluorescent indicators. It could likely be applied to all cell types and provide new biochemical insights at the single organelle level not available from organelle population level studies.

  18. Objective Clustering of Proteins Based on Subcellular Location Patterns

    Directory of Open Access Journals (Sweden)

    Xiang Chen

    2005-01-01

    Full Text Available The goal of proteomics is the complete characterization of all proteins. Efforts to characterize subcellular location have been limited to assigning proteins to general categories of organelles. We have previously designed numerical features to describe location patterns in microscope images and developed automated classifiers that distinguish major subcellular patterns with high accuracy (including patterns not distinguishable by visual examination. The results suggest the feasibility of automatically determining which proteins share a single location pattern in a given cell type. We describe an automated method that selects the best feature set to describe images for a given collection of proteins and constructs an effective partitioning of the proteins by location. An example for a limited protein set is presented. As additional data become available, this approach can produce for the first time an objective systematics for protein location and provide an important starting point for discovering sequence motifs that determine localization.

  19. Well Leg Compartment Syndrome After Abdominal Surgery

    DEFF Research Database (Denmark)

    Christoffersen, Jens Krogh; Hove, Lars Dahlgaard; Mikkelsen, Kim Lyngby

    2017-01-01

    BACKGROUND: Well leg compartment syndrome (WLCS) is a complication to abdominal surgery. We aimed to identify risk factors for and outcome of WLCS in Denmark and literature. METHODS: Prospectively collected claims to the Danish Patient Compensation Association (DPCA) concerning WLCS after abdominal...... surgery (p = 0.04). Duration of the abdominal surgery was 4 times as important as the diagnostic delay for severity of the final outcome. DNPR recorded 4 new cases/year, and half were reported to DPCA. CONCLUSION: The first 24 h following abdominal surgery of >4 h' duration with elevated legs observation...... for WLCS should be standard. Pain in the calf is indicative of WLCS, and elevated serum CK can support the diagnosis. Mannitol infusion and acute four-compartment fasciotomy of the lower leg is the treatment. The risk of severe outcome of WLCS increases with duration of the primary operation. A broad...

  20. Compartment syndrome in patients with haemophilia

    Science.gov (United States)

    Donaldson, James; Goddard, Nicholas

    2015-01-01

    Background Acute compartment syndrome (ACS) is an uncommon but potentially devastating condition. Methods and results There are scattered case reports and case series in the literature of ACS in persons with haemophilia (PWH), and even fewer in PWH and inhibitors. The management of compartment syndrome in these scenarios is controversial and often anecdotal. In addition haematological outcomes are frequently quoted but functional outcomes are generally overlooked. This article aims to provide an overview of ACS and its contemporary management. We also review the literature and outcomes of patients with haemophilia who develop ACS in an effort to assess the best treatment modality. Conclusion In the majority of cases ACS settles with normalisation of the clotting cascade. Specialist haematological input is mandatory before surgical intervention should be considered, especially in PWH and inhibitors. PMID:26566325

  1. Multi-compartment Aerosol Transport Model

    Energy Technology Data Exchange (ETDEWEB)

    Hubbard, Joshua Allen; Santarpia, Joshua; Brotherton, Christopher M.; Omana, Michael Alexis; Rivera, Danielle; Lucero, Gabriel Anthony

    2017-06-01

    A simple aerosol transport model was developed for a multi-compartmented cleanroom. Each compartment was treated as a well-mixed volume with ventilating supply and return air. Gravitational settling, intercompartment transport, and leakage of exterior air into the system were included in the model. A set of first order, coupled, ordinary differential equations was derived from the conservation equations of aerosol mass and air mass. The system of ODEs was then solved in MATLAB using pre-existing numerical methods. The model was verified against cases of (1) constant inlet-duct concentration, and (2) exponentially decaying inlet-duct concentration. Numerical methods resulted in normalized error of less than 10 -9 when model solutions were compared to analytical solutions. The model was validated against experimental measurements from a single field test and showed good agreement in the shape and magnitude of the aerosol concentration profile with time.

  2. Postoperative gastric dilatation causing abdominal compartment syndrome

    Directory of Open Access Journals (Sweden)

    Krausz Michael M

    2008-01-01

    Full Text Available Abstract Objective To study the effect of postoperative gastric dilatation on intra-abdominal pressure (IAP. Design and setting Single case report from a primary teaching hospital. Patients and methods A 72-year-old woman demonstrated a sudden respiratory and cardiovascular collapse following resection of a retroperitoneal sarcoma. This collapse was caused by abdominal compartment syndrome due to gastric dilatation. Results The patient was re-explored, an enormously distended stomach was found with the nasogastric tube situated in a small sliding hernia which prevented drainage of the distended stomach. Re-positioning of the nasogastric tube, allowed the decompression of the stomach and the patient's condition immediately improved. Conclusion Acute abdominal distention following major abdominal surgery may result from acute gastric dilatation, leading to oliguria and increased airway pressures. Untreated gastric dilatation can cause abdominal compartment syndrome.

  3. Postoperative gastric dilatation causing abdominal compartment syndrome.

    Science.gov (United States)

    Mahajna, Ahmad; Mitkal, Sharon; Krausz, Michael M

    2008-01-31

    To study the effect of postoperative gastric dilatation on intra-abdominal pressure (IAP). Single case report from a primary teaching hospital. A 72-year-old woman demonstrated a sudden respiratory and cardiovascular collapse following resection of a retroperitoneal sarcoma. This collapse was caused by abdominal compartment syndrome due to gastric dilatation. The patient was re-explored, an enormously distended stomach was found with the nasogastric tube situated in a small sliding hernia which prevented drainage of the distended stomach. Re-positioning of the nasogastric tube, allowed the decompression of the stomach and the patient's condition immediately improved. Acute abdominal distention following major abdominal surgery may result from acute gastric dilatation, leading to oliguria and increased airway pressures. Untreated gastric dilatation can cause abdominal compartment syndrome.

  4. Evaluation and comparison of mammalian subcellular localization prediction methods

    Directory of Open Access Journals (Sweden)

    Fink J Lynn

    2006-12-01

    Full Text Available Abstract Background Determination of the subcellular location of a protein is essential to understanding its biochemical function. This information can provide insight into the function of hypothetical or novel proteins. These data are difficult to obtain experimentally but have become especially important since many whole genome sequencing projects have been finished and many resulting protein sequences are still lacking detailed functional information. In order to address this paucity of data, many computational prediction methods have been developed. However, these methods have varying levels of accuracy and perform differently based on the sequences that are presented to the underlying algorithm. It is therefore useful to compare these methods and monitor their performance. Results In order to perform a comprehensive survey of prediction methods, we selected only methods that accepted large batches of protein sequences, were publicly available, and were able to predict localization to at least nine of the major subcellular locations (nucleus, cytosol, mitochondrion, extracellular region, plasma membrane, Golgi apparatus, endoplasmic reticulum (ER, peroxisome, and lysosome. The selected methods were CELLO, MultiLoc, Proteome Analyst, pTarget and WoLF PSORT. These methods were evaluated using 3763 mouse proteins from SwissProt that represent the source of the training sets used in development of the individual methods. In addition, an independent evaluation set of 2145 mouse proteins from LOCATE with a bias towards the subcellular localization underrepresented in SwissProt was used. The sensitivity and specificity were calculated for each method and compared to a theoretical value based on what might be observed by random chance. Conclusion No individual method had a sufficient level of sensitivity across both evaluation sets that would enable reliable application to hypothetical proteins. All methods showed lower performance on the LOCATE

  5. Isolated medial foot compartment syndrome after ankle sprain.

    Science.gov (United States)

    Cortina, Josep; Amat, Carles; Selga, Jordi; Corona, Pablo Salvador

    2014-03-01

    Foot compartment syndrome is a serious potential complication of foot crush injury, fractures, surgery, and vascular injury. An acute compartment syndrome isolated to the medial compartment of the foot after suffering an ankle sprain is a rare complication. We report the case of a 31-year-old man who developed a medial foot compartment syndrome after suffering a deltoid ligament rupture at ankle while playing football. The patient underwent a medial compartment fasciotomy with resolution of symptoms. Compartment syndromes of the foot are rare and have been reported to occur after severe trauma. But, there are some reports in the literature of acute exertional compartment syndrome. In our case, the compartment syndrome appeared after an ankle sprain without vascular injuries associated. Copyright © 2013 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  6. Computed tomography of the cervical compartments on the computer tomogram

    Energy Technology Data Exchange (ETDEWEB)

    Zaunbauer, W.; Haertel, M.

    1984-02-01

    The computed tomographic anatomy of the cervical compartments, with emphasis on the fascial planes of the neck, is described. Typical disease processes within these fascial confined compartments have been documented.

  7. Decompressive laparotomy for abdominal compartment syndrome

    Science.gov (United States)

    Kimball, E.; Malbrain, M.; Nesbitt, I.; Cohen, J.; Kaloiani, V.; Ivatury, R.; Mone, M.; Debergh, D.; Björck, M.

    2016-01-01

    Background The effect of decompressive laparotomy on outcomes in patients with abdominal compartment syndrome has been poorly investigated. The aim of this prospective cohort study was to describe the effect of decompressive laparotomy for abdominal compartment syndrome on organ function and outcomes. Methods This was a prospective cohort study in adult patients who underwent decompressive laparotomy for abdominal compartment syndrome. The primary endpoints were 28‐day and 1‐year all‐cause mortality. Changes in intra‐abdominal pressure (IAP) and organ function, and laparotomy‐related morbidity were secondary endpoints. Results Thirty‐three patients were included in the study (20 men). Twenty‐seven patients were surgical admissions treated for abdominal conditions. The median (i.q.r.) Acute Physiology And Chronic Health Evaluation (APACHE) II score was 26 (20–32). Median IAP was 23 (21–27) mmHg before decompressive laparotomy, decreasing to 12 (9–15), 13 (8–17), 12 (9–15) and 12 (9–14) mmHg after 2, 6, 24 and 72 h. Decompressive laparotomy significantly improved oxygenation and urinary output. Survivors showed improvement in organ function scores, but non‐survivors did not. Fourteen complications related to the procedure developed in eight of the 33 patients. The abdomen could be closed primarily in 18 patients. The overall 28‐day mortality rate was 36 per cent (12 of 33), which increased to 55 per cent (18 patients) at 1 year. Non‐survivors were no different from survivors, except that they tended to be older and on mechanical ventilation. Conclusion Decompressive laparotomy reduced IAP and had an immediate effect on organ function. It should be considered in patients with abdominal compartment syndrome. PMID:26891380

  8. Acute compartment syndrome of forearm and hand

    OpenAIRE

    T Chandraprakasam; R Ashok Kumar

    2011-01-01

    The diagnosis and treatment of the acute compartment syndrome is of paramount importance. Unless the viscious cycle is intervened at an appropriately early time it will result in irreversible damage leading to disability. In this review article we are discussing the basic pathophysiological process through which the various aetiological factors causing increased compartmental pressure lead to the progressive death of muscles and nerves. We also discuss the various clinical features that aid i...

  9. Predicting subcellular location of proteins using integrated-algorithm method.

    Science.gov (United States)

    Cai, Yu-Dong; Lu, Lin; Chen, Lei; He, Jian-Feng

    2010-08-01

    Protein's subcellular location, which indicates where a protein resides in a cell, is an important characteristic of protein. Correctly assigning proteins to their subcellular locations would be of great help to the prediction of proteins' function, genome annotation, and drug design. Yet, in spite of great technical advance in the past decades, it is still time-consuming and laborious to experimentally determine protein subcellular locations on a high throughput scale. Hence, four integrated-algorithm methods were developed to fulfill such high throughput prediction in this article. Two data sets taken from the literature (Chou and Elrod, Protein Eng 12:107-118, 1999) were used as training set and test set, which consisted of 2,391 and 2,598 proteins, respectively. Amino acid composition was applied to represent the protein sequences. The jackknife cross-validation was used to test the training set. The final best integrated-algorithm predictor was constructed by integrating 10 algorithms in Weka (a software tool for tackling data mining tasks, http://www.cs.waikato.ac.nz/ml/weka/ ) based on an mRMR (Minimum Redundancy Maximum Relevance, http://research.janelia.org/peng/proj/mRMR/ ) method. It can achieve correct rate of 77.83 and 80.56% for the training set and test set, respectively, which is better than all of the 60 algorithms collected in Weka. This predicting software is available upon request.

  10. Intracellular And Subcellular Partitioning Of Nickel In Aureococcus Anophagefferens

    Science.gov (United States)

    Wang, B.; Axe, L.; Wei, L.; Bagheri, S.; Michalopoulou, Z.

    2008-12-01

    Brown tides are caused by Aureococcus anophagefferens, a species of Pelagophyceae, and have been observed in NY/NJ waterways effecting ecosystems by attenuating light, changing water color, reducing eelgrass beds, decreasing shellfisheries, and further impacting the food web by reducing phytoplankton. Although the impact of macronutrients and iron on A. anophagefferens has been well studied, contaminants, and specifically trace metals have not. In long-term experiments designed to investigate the growth and toxicity, Cd, Cu, Ni, and Zn exposure was evaluated over 10-13 to 10-7 M for the free metal ion. While growth was inhibited or terminated from exposure to Cd and Cu, nickel addition ([Ni2+]: 10-11.23 to 10-10.23 M) promoted A. anophagefferens growth. Short-term experiments are being conducted to better understand mechanistically nickel speciation and distribution. Both total intracellular and subcellular metal concentrations are being assessed with radio-labeled 63Ni. Subcellular fractions are defined as metal-sensitive fractions (MSF) constituting organelles, cell debris, and heat-denatured protein [HDP] and biologically detoxified metal comprising heat-stabilized protein [HSP] and metal-rich granules [MRG]. Based on subcellular distribution, aqueous [Ni2+] concentrations, and A. anophagefferens growth rates, potential reaction pathways promoting A. anophagefferens growth can be addressed.

  11. [Acute compartment syndrome after a bowling game].

    Science.gov (United States)

    Meyer, C Y; Braun, K F; Huber-Wagner, S; Neu, J

    2015-11-01

    A 28-year-old male patient was initially conservatively treated by a general physician for muscle strain of the right calf after a bowling game. Due to increasing pain and swelling of the lower leg 5 days later, the differential diagnosis of a deep vein thrombosis was considered. Furthermore, the onset of neurological deficits and problems with raising the foot prompted inclusion of compartment syndrome in the differential diagnosis for the first time. Admission to hospital for surgical intervention was scheduled for the following day. At this point in time the laboratory results showed a negative d-dimer value and greatly increased C-reactive protein level. On day 6 a dermatofasciotomy was performed which revealed extensive muscular necrosis with complete palsy of the peroneal nerve. In the following lawsuit the patient accused the surgeon of having misdiagnosed the slow-onset compartment syndrome and thus delaying correct and mandatory treatment. The arbitration board ruled that the surgeon should have performed fasciotomy immediately on day 5 at the patient's consultation. The clinical presentation of progressive pain, swelling of the lower leg in combination with peroneal palsy must lead to the differential diagnosis of compartment syndrome resulting in adequate therapy. The delay of immediate surgery, therefore, was assessed to be faulty as this knowledge is to be expected of a surgeon.

  12. Salus: Kernel Support for Secure Process Compartments

    Directory of Open Access Journals (Sweden)

    Raoul Strackx

    2015-01-01

    Full Text Available Consumer devices are increasingly being used to perform security and privacy critical tasks. The software used to perform these tasks is often vulnerable to attacks, due to bugs in the application itself or in included software libraries. Recent work proposes the isolation of security-sensitive parts of applications into protected modules, each of which can be accessed only through a predefined public interface. But most parts of an application can be considered security-sensitive at some level, and an attacker who is able to gain inapplication level access may be able to abuse services from protected modules. We propose Salus, a Linux kernel modification that provides a novel approach for partitioning processes into isolated compartments sharing the same address space. Salus significantly reduces the impact of insecure interfaces and vulnerable compartments by enabling compartments (1 to restrict the system calls they are allowed to perform, (2 to authenticate their callers and callees and (3 to enforce that they can only be accessed via unforgeable references. We describe the design of Salus, report on a prototype implementation and evaluate it in terms of security and performance. We show that Salus provides a significant security improvement with a low performance overhead, without relying on any non-standard hardware support.

  13. A ranking of diffusion MRI compartment models with in vivo human brain data

    Science.gov (United States)

    Ferizi, Uran; Schneider, Torben; Panagiotaki, Eleftheria; Nedjati-Gilani, Gemma; Zhang, Hui; Wheeler-Kingshott, Claudia A M; Alexander, Daniel C

    2014-01-01

    Purpose Diffusion magnetic resonance imaging (MRI) microstructure imaging provides a unique noninvasive probe into tissue microstructure. The technique relies on biophysically motivated mathematical models, relating microscopic tissue features to the magnetic resonance (MR) signal. This work aims to determine which compartment models of diffusion MRI are best at describing measurements from in vivo human brain white matter. Methods Recent work shows that three compartment models, designed to capture intra-axonal, extracellular, and isotropically restricted diffusion, best explain multi-b-value data sets from fixed rat corpus callosum. We extend this investigation to in vivo by using a live human subject on a clinical scanner. The analysis compares models of one, two, and three compartments and ranks their ability to explain the measured data. We enhance the original methodology to further evaluate the stability of the ranking. Results As with fixed tissue, three compartment models explain the data best. However, a clearer hierarchical structure and simpler models emerge. We also find that splitting the scanning into shorter sessions has little effect on the ranking of models, and that the results are broadly reproducible across sessions. Conclusion Three compartments are required to explain diffusion MR measurements from in vivo corpus callosum, which informs the choice of model for microstructure imaging applications in the brain. Magn Reson Med 72:1785–1792, 2014. © 2013 The authors. Magnetic Resonance in Medicine Published by Wiley Periodicals, Inc. on behalf of International Society of Medicine in Resonance. PMID:24347370

  14. Locating proteins in the cell using TargetP, SignalP and related tools

    DEFF Research Database (Denmark)

    Emanuelsson, O.; Brunak, Søren; von Heijne, G.

    2007-01-01

    of methods to predict subcellular localization based on these sorting signals and other sequence properties. We then outline how to use a number of internet-accessible tools to arrive at a reliable subcellular localization prediction for eukaryotic and prokaryotic proteins. In particular, we provide detailed...

  15. Diverse subcellular localizations of the insect CMP-sialic acid synthetases.

    Science.gov (United States)

    Di, Wu; Fujita, Akiko; Hamaguchi, Kayo; Delannoy, Philippe; Sato, Chihiro; Kitajima, Ken

    2017-04-01

    The occurrence and biological importance of sialic acid (Sia) and its metabolic enzymes in insects have been studied using Drosophila melanogaster. The most prominent feature of D. melanogaster CMP-Sia synthetase (DmCSS) is its Golgi-localization, contrasted with nuclear localization of vertebrate CSSs. However, it remains unclear if the Golgi-localization is common to other insect CSSs and why it happens. To answer these questions, Aedes aegypti (mosquito) CSS (AaCSS) and Tribolium castaneum (beetle) CSS (TcCSS) were cloned and characterized for their activity and subcellular localization. Our new findings show: (1) AaCSS and TcCSS share a common overall structure with DmCSS in terms of evolutionarily conserved motifs and the absence of the C-terminal domain typical to vertebrate CSSs; (2) when expressed in mammalian and insect cells, AaCSS and TcCSS showed in vivo and in vitro CSS activities, similar to DmCSS. In contrast, when expressed in bacteria, they lacked CSS activity because the N-terminal hydrophobic region appeared to induce protein aggregation; (3) when expressed in Drosophila S2 cells, AaCSS and TcCSS were predominantly localized in the ER, but not in the Golgi. Surprisingly, DmCSS was mainly secreted into the culture medium, although partially detected in Golgi. Consistent with these results, the N-terminal hydrophobic regions of AaCSS and TcCSS functioned as a signal peptide to render them soluble in the ER, while the N-terminus of DmCSS functioned as a membrane-spanning region of type II transmembrane proteins whose cytosolic KLK sequence functioned as an ER export signal. Accordingly, the differential subcellular localization of insect CSSs are distinctively more diverse than previously recognized. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Compartment Syndrome of the Hand: A Little Thought about Diagnosis

    Science.gov (United States)

    Reichman, Eric F.

    2016-01-01

    Compartment syndrome of the forearm is a well described entity but there have been relatively few case reports in the emergency medicine literature of hand compartment syndromes (HCS). Prompt recognition and treatment of this potential limb threat are essential to minimize morbidity and mortality. Presented is a case of a documented hand compartment syndrome following a motor vehicle collision. PMID:27293917

  17. Lower limb compartment syndrome as a complication of radical hysterectomy

    OpenAIRE

    Oman, Sarah A.; Schwarz, Daniel; Muntz, Howard G.

    2016-01-01

    Highlights ? Compartment syndrome is a rare complication of prolonged lithotomy position. ? We report a case of compartment syndrome complicating radical hysterectomy. ? Prompt diagnosis is crucial to reduce morbidity from compartment syndrome. ? Awareness of this complication allows surgeons to address modifiable risk factors.

  18. Protein redox chemistry: post-translational cysteine modifications that regulate signal transduction and drug pharmacology

    Directory of Open Access Journals (Sweden)

    Revati eWani

    2014-10-01

    Full Text Available The perception of reactive oxygen species (ROS has evolved over the past decade from agents of cellular damage to secondary messengers which modify signaling proteins in physiology and the disease state (e.g. cancer. New protein targets of specific oxidation are rapidly being identified. One emerging class of redox modification occurs to the thiol side chain of cysteine residues which can produce multiple chemically-distinct alterations to the protein (e.g. sulfenic/sulfinic/sulfonic acid, disulfides. These post-translational modifications (PTM are shown to affect the protein structure and function. Because redox-sensitive proteins can traffic between subcellular compartments that have different redox environments, cysteine oxidation enables a spatio-temporal control to signaling. Understanding ramifications of these oxidative modifications to the functions of signaling proteins is crucial for understanding cellular regulation as well as for informed-drug discovery process. The effects of EGFR oxidation of Cys797 on inhibitor pharmacology are presented to illustrate the principle. Taken together, cysteine redox PTM can impact both cell biology and drug pharmacology.

  19. Compartment-specific metabolomics for CHO reveals that ATP pools in mitochondria are much lower than in cytosol.

    Science.gov (United States)

    Matuszczyk, Jens-Christoph; Teleki, Attila; Pfizenmaier, Jennifer; Takors, Ralf

    2015-10-01

    Mammalian cells show a compartmented metabolism. Getting access to subcellular metabolite pools is of high interest to understand the cells' metabolomic state. Therefore a protocol is developed and applied for monitoring compartment-specific metabolite and nucleotide pool sizes in Chinese hamster ovary (CHO) cells. The approach consists of a subtracting filtering method separating cytosolic components from physically intact mitochondrial compartments. The internal standards glucose-6-phosphate and cis-aconitate were chosen to quantify cytosolic secession and mitochondrial membrane integrity. Extracts of related fractions were studied by liquid chromatography-isotope dilution mass spectrometry for the absolute quantification of a subset of glycolytic and tricarboxylic acid cycle intermediates together with the adenylate nucleotides ATP, ADP and AMP. The application of the protocol revealed highly dynamic changes in the related pool sizes as a function of distinct cultivation periods of IgG1 producing CHO cells. Mitochondrial and cytosolic pool dynamics were in agreement with anticipated metabolite pools of independent studies. The analysis of adenosine phosphate levels unraveled significantly higher ATP levels in the cytosol leading to the hypothesis that mitochondria predominantly serve for fueling ATP into the cytosol where it is tightly controlled at physiological adenylate energy charges about 0.9. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. The compartment syndrome: is the intra-compartment pressure a reliable indicator for early diagnosis?

    Science.gov (United States)

    Nudel, Iftah; Dorfmann, Luis; deBotton, Gal

    2017-12-11

    Compartment syndrome (CS) occurs when the pressure in an enclosed compartment increases due to tissue swelling or internal bleeding. As the intra-compartmental pressure (ICP) builds up, the blood flow to the tissue or the organ is compromised, resulting in ischemia, necrosis and damage to the nerves and other tissues. At the present there are no established diagnostic procedures, and clinical observations such as pain, paralysis and even compartment pressure monitoring are an unreliable determinant of the presence of the syndrome. Late diagnosis may result in fasciotomy, neurological dysfunctions, amputation and even death. Focusing on the frequently occurring CS of the lower leg, this work is aimed toward introducing a coherent, mechanically motivated analysis of the disease within the framework of poroelasticity. The fascia enclosing the compartment is treated as an inextensible and impermeable layer, and the tissue inside the compartment is represented as a fully saturated poroelastic solid. The model quantitatively predicts the highly non-uniform ICP buildup as a function of both time and location. These findings, which are in good agreement with clinical observations reported in the literature, shed light on the difficulties associated with the identification of the syndrome and may assist in improved diagnostic procedures. © The authors 2016. Published by Oxford University Press on behalf of the Institute of Mathematics and its Applications. All rights reserved.

  1. Subcellular Localization of HIV-1 gag-pol mRNAs Regulates Sites of Virion Assembly.

    Science.gov (United States)

    Becker, Jordan T; Sherer, Nathan M

    2017-03-15

    Full-length unspliced human immunodeficiency virus type 1 (HIV-1) RNAs serve dual roles in the cytoplasm as mRNAs encoding the Gag and Gag-Pol capsid proteins as well as genomic RNAs (gRNAs) packaged by Gag into virions undergoing assembly at the plasma membrane (PM). Because Gag is sufficient to drive the assembly of virus-like particles even in the absence of gRNA binding, whether viral RNA trafficking plays an active role in the native assembly pathway is unknown. In this study, we tested the effects of modulating the cytoplasmic abundance or distribution of full-length viral RNAs on Gag trafficking and assembly in the context of single cells. Increasing full-length viral RNA abundance or distribution had little-to-no net effect on Gag assembly competency when provided in trans In contrast, artificially tethering full-length viral RNAs or surrogate gag-pol mRNAs competent for Gag synthesis to non-PM membranes or the actin cytoskeleton severely reduced net virus particle production. These effects were explained, in large part, by RNA-directed changes to Gag's distribution in the cytoplasm, yielding aberrant subcellular sites of virion assembly. Interestingly, RNA-dependent disruption of Gag trafficking required either of two cis-acting RNA regulatory elements: the 5' packaging signal (Psi) bound by Gag during genome encapsidation or, unexpectedly, the Rev response element (RRE), which regulates the nuclear export of gRNAs and other intron-retaining viral RNAs. Taken together, these data support a model for native infection wherein structural features of the gag-pol mRNA actively compartmentalize Gag to preferred sites within the cytoplasm and/or PM.IMPORTANCE The spatial distribution of viral mRNAs within the cytoplasm can be a crucial determinant of efficient translation and successful virion production. Here we provide direct evidence that mRNA subcellular trafficking plays an important role in regulating the assembly of human immunodeficiency virus type 1 (HIV

  2. Particle bombardment-mediated transient expression to identify localization signals in plant disease resistance proteins and target sites for the proteolytic activity of pathogen effectors.

    Science.gov (United States)

    Takemoto, Daigo; Jones, David A

    2014-01-01

    Plant pathogens, including fungi, oomycetes, bacteria, aphids, and nematodes, produce a variety of effector proteins to counter plant disease resistance mechanisms. After delivery into the cytosol of the plant cell, effectors may target proteins localized to different compartments within the plant cell. Plants, in turn, have evolved disease resistance (R) proteins to recognize the action of effectors. Elucidation of the subcellular localization of pathogen effectors, the plant proteins they target, and plant disease resistance proteins is essential to fully understand their interactions during pathogen challenge. In recent years, expression of fluorescent protein fusions has been widely used to determine the subcellular localization of plant proteins and pathogen effectors. Use of fluorescent proteins enables researchers to monitor the dynamic behavior of proteins in living cells. Among various methods available for the introduction of genes into plant cells, particle bombardment-mediated transient expression is the most rapid method suitable for both the identification of localization signals in proteins of interest and their dissection via amino acid substitutions generated using site-directed mutagenesis. This chapter describes a rapid procedure for particle bombardment-mediated transient expression in leaf epidermal cells. This method is also applicable to detection of pathogen effector protease activities directed against target proteins in the plant cell and analysis of protease recognition sites within these target proteins.

  3. Opposing activities of LIT-1/NLK and DAF-6/patched-related direct sensory compartment morphogenesis in C. elegans.

    Directory of Open Access Journals (Sweden)

    Grigorios Oikonomou

    2011-08-01

    Full Text Available Glial cells surround neuronal endings to create enclosed compartments required for neuronal function. This architecture is seen at excitatory synapses and at sensory neuron receptive endings. Despite the prevalence and importance of these compartments, how they form is not known. We used the main sensory organ of C. elegans, the amphid, to investigate this issue. daf-6/Patched-related is a glia-expressed gene previously implicated in amphid sensory compartment morphogenesis. By comparing time series of electron-microscopy (EM reconstructions of wild-type and daf-6 mutant embryos, we show that daf-6 acts to restrict compartment size. From a genetic screen, we found that mutations in the gene lit-1/Nemo-like kinase (NLK suppress daf-6. EM and genetic studies demonstrate that lit-1 acts within glia, in counterbalance to daf-6, to promote sensory compartment expansion. Although LIT-1 has been shown to regulate Wnt signaling, our genetic studies demonstrate a novel, Wnt-independent role for LIT-1 in sensory compartment size control. The LIT-1 activator MOM-4/TAK1 is also important for compartment morphogenesis and both proteins line the glial sensory compartment. LIT-1 compartment localization is important for its function and requires neuronal signals. Furthermore, the conserved LIT-1 C-terminus is necessary and sufficient for this localization. Two-hybrid and co-immunoprecipitation studies demonstrate that the LIT-1 C-terminus binds both actin and the Wiskott-Aldrich syndrome protein (WASP, an actin regulator. We use fluorescence light microscopy and fluorescence EM methodology to show that actin is highly enriched around the amphid sensory compartment. Finally, our genetic studies demonstrate that WASP is important for compartment expansion and functions in the same pathway as LIT-1. The studies presented here uncover a novel, Wnt-independent role for the conserved Nemo-like kinase LIT-1 in controlling cell morphogenesis in conjunction with the

  4. Opposing activities of LIT-1/NLK and DAF-6/patched-related direct sensory compartment morphogenesis in C. elegans.

    Science.gov (United States)

    Oikonomou, Grigorios; Perens, Elliot A; Lu, Yun; Watanabe, Shigeki; Jorgensen, Erik M; Shaham, Shai

    2011-08-01

    Glial cells surround neuronal endings to create enclosed compartments required for neuronal function. This architecture is seen at excitatory synapses and at sensory neuron receptive endings. Despite the prevalence and importance of these compartments, how they form is not known. We used the main sensory organ of C. elegans, the amphid, to investigate this issue. daf-6/Patched-related is a glia-expressed gene previously implicated in amphid sensory compartment morphogenesis. By comparing time series of electron-microscopy (EM) reconstructions of wild-type and daf-6 mutant embryos, we show that daf-6 acts to restrict compartment size. From a genetic screen, we found that mutations in the gene lit-1/Nemo-like kinase (NLK) suppress daf-6. EM and genetic studies demonstrate that lit-1 acts within glia, in counterbalance to daf-6, to promote sensory compartment expansion. Although LIT-1 has been shown to regulate Wnt signaling, our genetic studies demonstrate a novel, Wnt-independent role for LIT-1 in sensory compartment size control. The LIT-1 activator MOM-4/TAK1 is also important for compartment morphogenesis and both proteins line the glial sensory compartment. LIT-1 compartment localization is important for its function and requires neuronal signals. Furthermore, the conserved LIT-1 C-terminus is necessary and sufficient for this localization. Two-hybrid and co-immunoprecipitation studies demonstrate that the LIT-1 C-terminus binds both actin and the Wiskott-Aldrich syndrome protein (WASP), an actin regulator. We use fluorescence light microscopy and fluorescence EM methodology to show that actin is highly enriched around the amphid sensory compartment. Finally, our genetic studies demonstrate that WASP is important for compartment expansion and functions in the same pathway as LIT-1. The studies presented here uncover a novel, Wnt-independent role for the conserved Nemo-like kinase LIT-1 in controlling cell morphogenesis in conjunction with the actin cytoskeleton

  5. A cadaver study into the number of fasciotomies required to decompress the anterior compartment in forearm compartment syndrome.

    Science.gov (United States)

    Benamran, Lionel; Masquelet, Alain Charles

    2017-11-27

    There is no typical approach for decompression of forearm compartment syndrome, due to contradictory considerations regarding the characteristics of forearm anterior compartment deep fascia. The main purpose of this study was to determine how many fasciae should be opened to fully decompress the forearm anterior compartment. Further, the compliance of the deep anterior compartment was also investigated, to strengthen our results. An experimental study of a laboratory model of acute forearm compartment syndrome was performed. A deep forearm injection of egg white was undertaken to create an acute forearm compartment syndrome in sixteen non-embalmed human forearms from six male and two female donors. The pressure in the superficial and deep anterior compartments was recorded four times, both before and after each fasciotomy and the compliance of the deep anterior compartment was calculated for each step. The first incision of the superficial lamina of the deep fascia was not sufficient to decrease the elevated compartment pressure in the superficial and deep anterior compartments. Whereas the pressures decreased to near-baseline levels, following the fasciotomy of the intermuscular septum observed posterior to the flexor carpi radialis. The last incision of the deep lamina of the deep anterior fascia had no noticeable impact. These observations supported the hypothesis of high compliance of the deep anterior compartment. Two successive incisions were necessary to decompress the anterior compartment: the incision of the superficial lamina of the deep fascia and the incision of the intermuscular septum.

  6. Calcium signals can freely cross the nuclear envelope in hippocampal neurons: somatic calcium increases generate nuclear calcium transients

    Directory of Open Access Journals (Sweden)

    Bading Hilmar

    2007-07-01

    Full Text Available Abstract Background In hippocampal neurons, nuclear calcium signaling is important for learning- and neuronal survival-associated gene expression. However, it is unknown whether calcium signals generated by neuronal activity at the cell membrane and propagated to the soma can unrestrictedly cross the nuclear envelope to invade the nucleus. The nuclear envelope, which allows ion transit via the nuclear pore complex, may represent a barrier for calcium and has been suggested to insulate the nucleus from activity-induced cytoplasmic calcium transients in some cell types. Results Using laser-assisted uncaging of caged calcium compounds in defined sub-cellular domains, we show here that the nuclear compartment border does not represent a barrier for calcium signals in hippocampal neurons. Although passive diffusion of molecules between the cytosol and the nucleoplasm may be modulated through changes in conformational state of the nuclear pore complex, we found no evidence for a gating mechanism for calcium movement across the nuclear border. Conclusion Thus, the nuclear envelope does not spatially restrict calcium transients to the somatic cytosol but allows calcium signals to freely enter the cell nucleus to trigger genomic events.

  7. Calcium signals can freely cross the nuclear envelope in hippocampal neurons: somatic calcium increases generate nuclear calcium transients

    Science.gov (United States)

    Eder, Anja; Bading, Hilmar

    2007-01-01

    Background In hippocampal neurons, nuclear calcium signaling is important for learning- and neuronal survival-associated gene expression. However, it is unknown whether calcium signals generated by neuronal activity at the cell membrane and propagated to the soma can unrestrictedly cross the nuclear envelope to invade the nucleus. The nuclear envelope, which allows ion transit via the nuclear pore complex, may represent a barrier for calcium and has been suggested to insulate the nucleus from activity-induced cytoplasmic calcium transients in some cell types. Results Using laser-assisted uncaging of caged calcium compounds in defined sub-cellular domains, we show here that the nuclear compartment border does not represent a barrier for calcium signals in hippocampal neurons. Although passive diffusion of molecules between the cytosol and the nucleoplasm may be modulated through changes in conformational state of the nuclear pore complex, we found no evidence for a gating mechanism for calcium movement across the nuclear border. Conclusion Thus, the nuclear envelope does not spatially restrict calcium transients to the somatic cytosol but allows calcium signals to freely enter the cell nucleus to trigger genomic events. PMID:17663775

  8. Sub-cellular trafficking of phytochemicals explored using auto-fluorescent compounds in maize cells

    Directory of Open Access Journals (Sweden)

    Grotewold Erich

    2003-12-01

    Full Text Available Abstract Background Little is known regarding the trafficking mechanisms of small molecules within plant cells. It remains to be established whether phytochemicals are transported by pathways similar to those used by proteins, or whether the expansion of metabolic pathways in plants was associated with the evolution of novel trafficking pathways. In this paper, we exploited the induction of green and yellow auto-fluorescent compounds in maize cultured cells by the P1 transcription factor to investigate their targeting to the cell wall and vacuole, respectively. Results We investigated the accumulation and sub-cellular localization of the green and yellow auto-fluorescent compounds in maize BMS cells expressing the P1 transcription factor from an estradiol inducible promoter. We established that the yellow fluorescent compounds accumulate inside the vacuole in YFBs that resemble AVIs. The green fluorescent compounds accumulate initially in the cytoplasm in large spherical GFBs. Cells accumulating GFBs also contain electron-dense structures that accumulate initially in the ER and which later appear to fuse with the plasma membrane. Structures resembling the GFBs were also observed in the periplasmic space of plasmolized cells. Ultimately, the green fluorescence accumulates in the cell wall, in a process that is insensitive to the Golgi-disturbing agents BFA and monensin. Conclusions Our results suggest the presence of at least two distinct trafficking pathways, one to the cell wall and the other to the vacuole, for different auto-fluorescent compounds induced by the same transcription factor in maize BMS cells. These compartments represent two of the major sites of accumulation of phenolic compounds characteristic of maize cells. The secretion of the green auto-fluorescent compounds occurs by a pathway that does not involve the TGN, suggesting that it is different from the secretion of most proteins, polysaccharides or epicuticular waxes. The

  9. Ultrasonic Apparatus and Method to Assess Compartment Syndrome

    Science.gov (United States)

    Yost, William T. (Inventor); Ueno, Toshiaki (Inventor); Hargens, Alan R. (Inventor)

    2009-01-01

    A process and apparatus for measuring pressure buildup in a body compartment that encases muscular tissue. The method includes assessing the body compartment configuration and identifying the effect of pulsatible components on compartment dimensions and muscle tissue characteristics. This process is used in preventing tissue necrosis, and in decisions of whether to perform surgery on the body compartment for prevention of Compartment Syndrome. An apparatus is used for measuring pressure build-up in the body compartment having components for imparting ultrasonic waves such as a transducer, placing the transducer to impart the ultrasonic waves, capturing the imparted ultrasonic waves, mathematically manipulating the captured ultrasonic waves and categorizing pressure build-up in the body compartment from the mathematical manipulations.

  10. Acute compartment syndrome of forearm and hand

    Science.gov (United States)

    Chandraprakasam, T.; Kumar, R. Ashok

    2011-01-01

    The diagnosis and treatment of the acute compartment syndrome is of paramount importance. Unless the viscious cycle is intervened at an appropriately early time it will result in irreversible damage leading to disability. In this review article we are discussing the basic pathophysiological process through which the various aetiological factors causing increased compartmental pressure lead to the progressive death of muscles and nerves. We also discuss the various clinical features that aid in the diagnosis and the role of intracompartmental pressure measurements. Finally we hope to ascertain the basic principles and the surgical techniques for treating this condition effectively. PMID:22022031

  11. [Intraabdominal hypertension and abdominal compartment syndrome

    DEFF Research Database (Denmark)

    Sonne, M.; Hilligsø, Jens Georg

    2008-01-01

    Intraabdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are rare conditions with high mortality. IAH is an intraabdominal pressure (IAP) above 12 mmHg and ACS an IAP above 20 mmHg with evidence of organ dysfunction. IAP is measured indirectly via the bladder or stomach. Various...... medical and surgical conditions increase the intraabdominal volume. When the content exceeds the compliance of the abdominal wall, the IAP rises. Increased IAP affects the functioning of the brain, lungs, circulation, kidneys, and bowel. The treatment of ACS is a reduction of IAP Udgivelsesdato: 2008/2/11...

  12. Acute compartment syndrome of forearm and hand

    Directory of Open Access Journals (Sweden)

    T Chandraprakasam

    2011-01-01

    Full Text Available The diagnosis and treatment of the acute compartment syndrome is of paramount importance. Unless the viscious cycle is intervened at an appropriately early time it will result in irreversible damage leading to disability. In this review article we are discussing the basic pathophysiological process through which the various aetiological factors causing increased compartmental pressure lead to the progressive death of muscles and nerves. We also discuss the various clinical features that aid in the diagnosis and the role of intracompartmental pressure measurements. Finally we hope to ascertain the basic principles and the surgical techniques for treating this condition effectively.

  13. Acute compartment syndrome of forearm and hand.

    Science.gov (United States)

    Chandraprakasam, T; Kumar, R Ashok

    2011-05-01

    The diagnosis and treatment of the acute compartment syndrome is of paramount importance. Unless the viscious cycle is intervened at an appropriately early time it will result in irreversible damage leading to disability. In this review article we are discussing the basic pathophysiological process through which the various aetiological factors causing increased compartmental pressure lead to the progressive death of muscles and nerves. We also discuss the various clinical features that aid in the diagnosis and the role of intracompartmental pressure measurements. Finally we hope to ascertain the basic principles and the surgical techniques for treating this condition effectively.

  14. Supraspinatus and infraspinatus compartment syndrome following scapular fracture.

    Science.gov (United States)

    Kenny, Ryan M; Beiser, Christopher W; Patel, Arun

    2013-01-01

    Acute compartment syndrome occurs when pressure within a confined fascial space rises to a level impairing microvascular perfusion to surrounding tissues.[1234567] The majority of the reported literature is based on lower extremity compartment syndrome, but any muscle group within an osteofascial compartment has the potential to develop compartment syndrome. We report a case of a 64-year-old male who developed an acute compartment syndrome of both the supraspinatus and infraspinatus after sustaining a severely comminuted scapula fracture. Diagnosis of compartment syndrome was made after intracompartmental pressure measurements of the supraspinatus and infraspinatus revealed pressures within 30 mmHg of the diastolic blood pressure, prompting emergency decompressive fasciotomy. At final follow-up, the examination revealed full shoulder strength with near-full range of motion. There were no signs of sequelae from compartment syndrome at any point. Few case reports describe compartment syndrome of the periscapular fascial compartments. However, these cases were either retrospectively diagnosed[89] or diagnosed via magnetic resonance imaging (MRI) findings and lab values.[910] Surgical management of acute compartment syndrome of the supraspinatus has been reported in only one other case.[10] To our knowledge, we report the only case of a patient with acute compartment syndrome of both the supraspinatus and infraspinatus compartments treated with emergent decompressive fasciotomy. Due to the devastating complications and functional loss of a missed diagnosis of compartment syndrome, a high index of clinical suspicion for developing compartment syndrome must be maintained in every fracture setting, regardless of anatomic location or rarity of reported cases.

  15. What is the clinical relevance of different lung compartments?

    Science.gov (United States)

    2009-01-01

    The lung consists of at least seven compartments with relevance to immune reactions. Compartment 1 - the bronchoalveolar lavage (BAL), which represents the cells of the bronchoalveolar space: From a diagnostic point of view the bronchoalveolar space is the most important because it is easily accessible in laboratory animals, as well as in patients, using BAL. Although this technique has been used for several decades it is still unclear to what extent the BAL represents changes in other lung compartments. Compartment 2 - bronchus-associated lymphoid tissue (BALT): In the healthy, BALT can be found only in childhood. The role of BALT in the development of the mucosal immunity of the pulmonary surfaces has not yet been resolved. However, it might be an important tool for inhalative vaccination strategies. Compartment 3 - conducting airway mucosa: A third compartment is the bronchial epithelium and the submucosa, which both contain a distinct pool of leukocytes (e.g. intraepithelial lymphocytes, IEL). This again is also accessible via bronchoscopy. Compartment 4 - draining lymph nodes/Compartment 5 - lung parenchyma: Transbronchial biopsies are more difficult to perform but provide access to two additional compartments - lymph nodes with the draining lymphatics and lung parenchyma, which roughly means "interstitial" lung tissue. Compartment 6 - the intravascular leukocyte pool: The intravascular compartment lies between the systemic circulation and inflamed lung compartments. Compartment 7 - periarterial space: Finally, there is a unique, lung-specific space around the pulmonary arteries which contains blood and lymph capillaries. There are indications that this "periarterial space" may be involved in the pulmonary host defense. All these compartments are connected but the functional network is not yet fully understood. A better knowledge of the complex interactions could improve diagnosis and therapy, or enable preventive approaches of local immunization. PMID

  16. What is the clinical relevance of different lung compartments?

    Directory of Open Access Journals (Sweden)

    Pabst Reinhard

    2009-08-01

    Full Text Available Abstract The lung consists of at least seven compartments with relevance to immune reactions. Compartment 1 – the bronchoalveolar lavage (BAL, which represents the cells of the bronchoalveolar space: From a diagnostic point of view the bronchoalveolar space is the most important because it is easily accessible in laboratory animals, as well as in patients, using BAL. Although this technique has been used for several decades it is still unclear to what extent the BAL represents changes in other lung compartments. Compartment 2 – bronchus-associated lymphoid tissue (BALT: In the healthy, BALT can be found only in childhood. The role of BALT in the development of the mucosal immunity of the pulmonary surfaces has not yet been resolved. However, it might be an important tool for inhalative vaccination strategies. Compartment 3 – conducting airway mucosa: A third compartment is the bronchial epithelium and the submucosa, which both contain a distinct pool of leukocytes (e.g. intraepithelial lymphocytes, IEL. This again is also accessible via bronchoscopy. Compartment 4 – draining lymph nodes/Compartment 5 – lung parenchyma: Transbronchial biopsies are more difficult to perform but provide access to two additional compartments – lymph nodes with the draining lymphatics and lung parenchyma, which roughly means "interstitial" lung tissue. Compartment 6 – the intravascular leukocyte pool: The intravascular compartment lies between the systemic circulation and inflamed lung compartments. Compartment 7 – periarterial space: Finally, there is a unique, lung-specific space around the pulmonary arteries which contains blood and lymph capillaries. There are indications that this "periarterial space" may be involved in the pulmonary host defense. All these compartments are connected but the functional network is not yet fully understood. A better knowledge of the complex interactions could improve diagnosis and therapy, or enable preventive approaches

  17. Acute atraumatic compartment syndrome in an athlete: a case report.

    Science.gov (United States)

    Stollsteimer, G T; Shelton, W R

    1997-07-01

    To present the case of a college football player with acute, atraumatic, exercise-induced compartment syndrome in the leg. Acute, atraumatic, exercise-induced compartment syndrome is an infrequently reported cause of leg pain in the athlete. If left untreated, acute compartment syndrome can cause muscle necrosis. Chronic exertional compartment syndrome, medial tibial syndrome, stress fracture. Treatment consists of compartment fasciotomy. This previously healthy, but unconditioned, athlete developed severe anterolateral left leg pain after two days of fall practice in which he was unable to run a mile in 7.5 minutes. Physical examination by the team physician revealed acute compartment syndrome, and an emergency anterolateral compartment fasciotomy was performed. Second-look débridement performed 48 hours later revealed no significant change in the necrotic appearance of the anterior compartment soft tissue. Therefore, the dead muscle was completely débrided, and a free-flap latissumus dorsi graft was used for coverage of the wound. With recovery, strength returned to normal in the lateral compartment but remained 0/5 in the anterior compartment. The patient had persistent sensory loss in the distributions of the superficial and deep peroneal nerves. Although much less common than the more frequent causes of leg pain (ie, chronic exertional compartment syndrome, medial tibial syndrome, stress fracture), acute compartment syndrome is potentially more devastating. When the increased intracompartmental pressure within a closed tissue space exceeds capillary perfusion pressure, tissue perfusion is decreased, the soft tissue becomes ischemic, and cells die. The most important clinical diagnostic signs of compartment syndrome are pain with passive stretching of the compartment and pain out of proportion to the results of the physical examination.

  18. The proprotein convertase SKI-1/S1P: alternate translation and subcellular localization.

    Science.gov (United States)

    Pullikotil, Philomena; Benjannet, Suzanne; Mayne, Janice; Seidah, Nabil G

    2007-09-14

    Subtilisin kexin isozyme-1 (SKI-1) represents the first mammalian member of secretory subtilisin-like processing enzymes that cleaves after nonbasic residues. It is synthesized as an inactive precursor that undergoes three sequential autocatalytic processing steps of its N-terminal prosegment and an ectodomain shedding at a site near the transmembrane domain. The various cellular functions of SKI-1 emphasize the need to understand the sites of its activation and shedding. We have previously shown that SKI-1 undergoes autocatalytic shedding at the sequence KHQKLL(953) downward arrow, resulting in a membrane-bound stump called St-1 (amino acids 954-1052). However, little is known about the cellular localization of SKI-1 or its shed forms. In the present study, we have further identified a smaller C-terminal fragment St-2 generated closer to the transmembrane domain. By sequencing and mass spectrometric analysis, the start site and the molecular mass of St-2 were determined. Site-directed mutagenesis revealed the critical amino acid involved in this novel process. Mutation of Met(990) to M990A, M990I, and M990L failed to generate St-2, suggesting an internal alternate translation event at Met(990), as confirmed by an in vitro transcription/translation assay. Confocal microscopy defined the subcellular localization of SKI-1 and its fragments. The data show that most of membrane-bound SKI-1 and its stumps St-1 and St-2 localize to the Golgi and can enter the endosomal/lysosomal compartments but do not sort to the cell surface. Deletion studies showed that the transmembrane domain of SKI-1 determines its trafficking. Finally, rSt-1 and rSt-2 seem to affect the processing of ATF6 by SKI-1, but cellular stress does not regulate the production of St-2.

  19. Raised compartment pressures are frequently observed with tibial shaft fractures despite the absence of compartment syndrome: A prospective cohort study.

    Science.gov (United States)

    Ho, Kelvin Lor Kah; Sing, Nicholas Yeoh Ching; Wong, Khai Phang; Huat, Andy Wee Teck

    2017-01-01

    To measure the intracompartmental pressures surrounding tibial fractures not exhibiting any clinical evidence of compartment syndrome. Our hypothesis was that pressures often exceed the recommended threshold of fasciotomy despite the absence of compartment syndrome, and hence diagnosis based on pressure measurements alone is unreliable. Thirteen consecutive patients with closed tibial shaft fractures without clinical suspicion of compartment syndrome, and who were planned for intramedullary nailing, were prospectively enrolled. Compartment pressures ( P) in all four compartments of the affected leg were measured at the start of surgery and immediately after tibial reaming, and differential pressures (delta P) were calculated based on the diastolic blood pressure prior to induction of anaesthesia. No patients required reoperation in the post-operative period, as a result of an undiagnosed compartment syndrome. Using commonly quoted threshold pressure criteria, 62% (using P > 30 mmHg) and 23% of patients (using delta P compartment syndrome. We conclude that raised compartment pressures are frequently seen in patients with tibial shaft fractures; but in most cases, it does not equate to the presence of compartment syndrome. Diagnosis of compartment syndrome based on intracompartmental pressure measurements alone may result in unnecessary fasciotomies in a sizeable number of patients. Compartment syndrome remains a clinical diagnosis, and one which always needs to be considered when managing tibial fractures.

  20. Subcellular trafficking of mycobacteria : Implications for virulence and immunogenicity

    NARCIS (Netherlands)

    Houben, D.

    2011-01-01

    The aim of this thesis is to determine the properties of the compartment where mycobacteria end up after phagocytosis and which mycobacterial genes play a role in this process. In most cases, bacterial pathogens are taken up by the cell, processed in the endocytic pathway and eventually bacterial

  1. Functional dissociation of the basolateral transcytotic compartment from the apical phago-lysosomal compartment in human osteoclasts.

    Science.gov (United States)

    Meagher, James; Zellweger, René; Filgueira, Luis

    2005-05-01

    Tartrate-resistant acid phosphatase (TRAP) is essential for elimination of Staphylococcus aureus, the main infectious agent responsible for osteomyelitis. This in vitro study investigated uptake and processing of fluorescence-labeled S. aureus by human osteoclasts and dendritic cells. The cells were stained for TRAP and the acidic compartment using a fluorescence-based protocol. In dendritic cells, TRAP and bacteria were colocalized. In osteoclasts, there was no colocalization of bacteria, TRAP, or the acidic compartment, indicating that there are three distinct vesicular compartments: the apical phago-lysosomal compartment, the basal secretory compartment, and the basolateral transcytotic compartment. Dissociation of the TRAP-containing transcytotic vesicles from the apical phago-lysosomal compartment may restrain osteoclasts from eliminating S. aureus.

  2. Single point mutations result in the miss-sorting of Glut4 to a novel membrane compartment associated with stress granule proteins.

    Directory of Open Access Journals (Sweden)

    XiaoMei Song

    Full Text Available Insulin increases cellular glucose uptake and metabolism in the postprandial state by acutely stimulating the translocation of the Glut4 glucose transporter from intracellular membrane compartments to the cell surface in muscle and fat cells. The intracellular targeting of Glut4 is dictated by specific structural motifs within cytoplasmic domains of the transporter. We demonstrate that two leucine residues at the extreme C-terminus of Glut4 are critical components of a motif (IRM, insulin responsive motif involved in the sorting of the transporter to insulin responsive vesicles in 3T3L1 adipocytes. Light microscopy, immunogold electron microscopy, subcellular fractionation, and sedimentation analysis indicate that mutations in the IRM cause the aberrant targeting of Glut4 to large dispersed membrane vesicles that are not insulin responsive. Proteomic characterization of rapidly and slowly sedimenting membrane vesicles (RSVs and SSVs that were highly enriched by immunoadsorption for either wild-type Glut4 or an IRM mutant revealed that the major vesicle fraction containing the mutant transporter (IRM-RSVs possessed a relatively small and highly distinct protein population that was enriched for proteins associated with stress granules. We suggest that the IRM is critical for an early step in the sorting of Glut4 to insulin-responsive subcellular membrane compartments and that IRM mutants are miss-targeted to relatively large, amorphous membrane vesicles that may be involved in a degradation pathway for miss-targeted or miss-folded proteins or represent a transitional membrane compartment that Glut4 traverses en route to insulin responsive storage compartments.

  3. Narciclasine, a potential allelochemical, affects subcellular trafficking of auxin transporter proteins and actin cytoskeleton dynamics in Arabidopsis roots.

    Science.gov (United States)

    Hu, Yanfeng; Na, Xiaofan; Li, Jiaolong; Yang, Lijing; You, Jia; Liang, Xiaolei; Wang, Jianfeng; Peng, Liang; Bi, Yurong

    2015-12-01

    The present study documented the action of a potential allelochemical, narciclasine, on auxin transport in Arabidopsis by mainly affecting subcellular trafficking of PIN and AUX1 proteins and through interfering actin cytoskeletal organization. Narciclasine (NCS), an Amaryllidaceae alkaloid isolated from Narcissus tazetta bulbs, has potential allelopathic activity and affects auxin transport. However, little is known about the cellular mechanism of this inhibitory effect of NCS on auxin transport. The present study characterizes the effects of NCS at the cellular level using transgenic Arabidopsis plants harboring the promoters of PIN, in combination with PIN-GFP proteins or AUX1-YFP fusions. NCS treatment caused significant reduction in the abundance of PIN and AUX1 proteins at the plasma membrane (PM). Analysis of the subcellular distribution of PIN and AUX1 proteins in roots revealed that NCS induced the intracellular accumulation of auxin transporters, including PIN2, PIN3, PIN4, PIN7 and AUX1. However, other PM proteins, such as PIP2, BRI1, and low temperature inducible protein 6b (LTI6b), were insensitive to NCS treatment. NCS-induced PIN2 compartments were further defined using endocytic tracer FM 4-64 labeled early endosomes and suggested that this compound affects the endocytosis trafficking of PIN proteins. Furthermore, pharmacological analysis indicated that the brefeldin A (BFA)-insensitive pathway is employed in the cellular effects of NCS on PIN2 trafficking. Although NCS did not alter actin dynamics in vitro, it resulted in the depolymerization of the actin cytoskeleton in vivo. This disruption of actin filaments by NCS subsequently influences the actin-based vesicle motility. Hence, the elucidation of the specific role of NCS is useful for further understanding the mechanisms of allelopathy at the phytohormone levels.

  4. ALG-2 oscillates in subcellular localization, unitemporally with calcium oscillations

    DEFF Research Database (Denmark)

    la Cour, Jonas Marstrand; Mollerup, Jens; Berchtold, Martin Werner

    2007-01-01

    discovered that the subcellular distribution of a tagged version of ALG-2 could be directed by physiological external stimuli (including ATP, EGF, prostaglandin, histamine), which provoke intracellular Ca2+ oscillations. Cellular stimulation led to a redistribution of ALG-2 from the cytosol to a punctate...... localization in an oscillatory fashion unitemporally with Ca2+ oscillations, whereas a Ca2+-binding deficient mutant of ALG-2 did not redistribute. Using tagged ALG-2 as bait we identified its novel target protein Sec31A and based on the partial colocalization of endogenous ALG-2 and Sec31A we propose that ALG...

  5. Exploitation of eukaryotic subcellular targeting mechanisms by bacterial effectors.

    Science.gov (United States)

    Hicks, Stuart W; Galán, Jorge E

    2013-05-01

    Several bacterial species have evolved specialized secretion systems to deliver bacterial effector proteins into eukaryotic cells. These effectors have the capacity to modulate host cell pathways in order to promote bacterial survival and replication. The spatial and temporal context in which the effectors exert their biochemical activities is crucial for their function. To fully understand effector function in the context of infection, we need to understand the mechanisms that lead to the precise subcellular localization of effectors following their delivery into host cells. Recent studies have shown that bacterial effectors exploit host cell machinery to accurately target their biochemical activities within the host cell.

  6. Subcellular Localization of Carotenoid Biosynthesis in Synechocystis sp. PCC 6803.

    Directory of Open Access Journals (Sweden)

    Lifang Zhang

    Full Text Available The biosynthesis pathway of carotenoids in cyanobacteria is partly described. However, the subcellular localization of individual steps is so far unknown. Carotenoid analysis of different membrane subfractions in Synechocystis sp. PCC6803 shows that "light" plasma membranes have a high carotenoid/protein ratio, when compared to "heavier" plasma membranes or thylakoids. The localization of CrtQ and CrtO, two well-defined carotenoid synthesis pathway enzymes in Synechocystis, was studied by epitope tagging and western blots. Both enzymes are locally more abundant in plasma membranes than in thylakoids, implying that the plasma membrane has higher synthesis rates of β-carotene precursor molecules and echinenone.

  7. A Time- and Compartment-Specific Activation of Lung Macrophages in Hypoxic Pulmonary Hypertension.

    Science.gov (United States)

    Pugliese, Steven C; Kumar, Sushil; Janssen, William J; Graham, Brian B; Frid, Maria G; Riddle, Suzette R; El Kasmi, Karim C; Stenmark, Kurt R

    2017-06-15

    Studies in various animal models suggest an important role for pulmonary macrophages in the pathogenesis of pulmonary hypertension (PH). Yet, the molecular mechanisms characterizing the functional macrophage phenotype relative to time and pulmonary localization and compartmentalization remain largely unknown. In this study, we used a hypoxic murine model of PH in combination with FACS to quantify and isolate lung macrophages from two compartments over time and characterize their programing via RNA sequencing approaches. In response to hypoxia, we found an early increase in macrophage number that was restricted to the interstitial/perivascular compartment, without recruitment of macrophages to the alveolar compartment or changes in the number of resident alveolar macrophages. Principal component analysis demonstrated significant differences in overall gene expression between alveolar and interstitial macrophages (IMs) at baseline and after 4 and 14 d hypoxic exposure. Alveolar macrophages at both day 4 and 14 and IMs at day 4 shared a conserved hypoxia program characterized by mitochondrial dysfunction, proinflammatory gene activation, and mTORC1 signaling, whereas IMs at day 14 demonstrated a unique anti-inflammatory/proreparative programming state. We conclude that the pathogenesis of vascular remodeling in hypoxic PH involves an early compartment-independent activation of lung macrophages toward a conserved hypoxia program, with the development of compartment-specific programs later in the course of the disease. Thus, harnessing time- and compartment-specific differences in lung macrophage polarization needs to be considered in the therapeutic targeting of macrophages in hypoxic PH and potentially other inflammatory lung diseases. Copyright © 2017 by The American Association of Immunologists, Inc.

  8. Subcellular targeting of RGS9-2 is controlled by multiple molecular determinants on its membrane anchor, R7BP.

    Science.gov (United States)

    Song, Joseph H; Waataja, Jonathan J; Martemyanov, Kirill A

    2006-06-02

    RGS9-2, a member of the R7 regulators of G protein signaling (RGS) protein family of neuronal RGS, is a critical regulator of G protein signaling. In striatal neurons, RGS9-2 is tightly associated with a novel palmitoylated protein, R7BP (R7 family binding protein). Here we report that R7BP acts to target the localization of RGS9-2 to the plasma membrane. Examination of the subcellular distribution in native striatal neurons revealed that both R7BP and RGS9-2 are almost entirely associated with the neuronal membranes. In addition to the plasma membrane, a large portion of RGS9-2 was found in the neuronal specializations, the postsynaptic densities, where it forms complexes with R7BP and its constitutive partner Gbeta5. Using site-directed mutagenesis we found that the molecular determinants that specify the subcellular targeting of RGS9-2.Gbeta5.R7BP complex are contained within the 21 C-terminal amino acids of R7BP. This function of the C terminus was found to require the synergistic contributions of its two distinct elements, a polybasic motif and palmitoylated cysteines, which when combined are sufficient for directing the intracellular localization of the constituent protein. In differentiated neurons, the C-terminal targeting motif of R7BP was found to be essential for mediating its postsynaptic localization. In addition to the plasma membrane targeting elements, we identified two functional nuclear localization sequences that can mediate the import of R7BP into the nucleus upon depalmitoylation. These findings provide a mechanism for the subcellular targeting of RGS9-2 in neurons.

  9. Gluteal Compartment Syndrome After Prolonged Immobilisation

    Directory of Open Access Journals (Sweden)

    H.L. Liu

    2009-04-01

    Full Text Available Muscles in the gluteal region are confined by distinct fascial attachments which can potentially result in compartment syndrome. A 74-year-old chronic drinker was admitted to the medical ward after being found drunk on the street. He noticed acute painful swelling of the right side of his buttock the following morning and recalled a slip and fall prior to his blackout. The whole right half of the buttock was tense with erythematous overlying skin. Examination revealed sciatic nerve palsy and myoglobinuria. Emergency fasciotomy and debridement were performed. Intra-operative pressure measurement confirmed a grossly elevated intra-compartmental pressure. Gluteal compartment syndrome is an extremely rare condition and has only been scantily documented previously in case reports. Early diagnosis is crucial but delay recognition is common from lack of knowledge of the condition and readily results in permanent sciatic nerve injury and acute renal shutdown from myoglobinuria. Awareness of the condition, early diagnosis and prompt exploration provide the only chance of avoiding these devastating consequences. Acute swelling diffusely affecting the whole or one side of the buttock, a history of trauma and prolonged local pressure impingement associated with pain out of proportion to the clinical signs should raise a suspicion of this rare condition.

  10. In situ spatiotemporal mapping of flow fields around seeded stem cells at the subcellular length scale.

    Directory of Open Access Journals (Sweden)

    Min Jae Song

    2010-09-01

    Full Text Available A major hurdle to understanding and exploiting interactions between the stem cell and its environment is the lack of a tool for precise delivery of mechanical cues concomitant to observing sub-cellular adaptation of structure. These studies demonstrate the use of microscale particle image velocimetry (μ-PIV for in situ spatiotemporal mapping of flow fields around mesenchymal stem cells, i.e. murine embryonic multipotent cell line C3H10T1/2, at the subcellular length scale, providing a tool for real time observation and analysis of stem cell adaptation to the prevailing mechanical milieu. In the absence of cells, computational fluid dynamics (CFD predicts flow regimes within 12% of μ-PIV measures, achieving the technical specifications of the chamber and the flow rates necessary to deliver target shear stresses at a particular height from the base of the flow chamber. However, our μ-PIV studies show that the presence of cells per se as well as the density at which cells are seeded significantly influences local flow fields. Furthermore, for any given cell or cell seeding density, flow regimes vary significantly along the vertical profile of the cell. Hence, the mechanical milieu of the stem cell exposed to shape changing shear stresses, induced by fluid drag, varies with respect to proximity of surrounding cells as well as with respect to apical height. The current study addresses a previously unmet need to predict and observe both flow regimes as well as mechanoadaptation of cells in flow chambers designed to deliver precisely controlled mechanical signals to live cells. An understanding of interactions and adaptation in response to forces at the interface between the surface of the cell and its immediate local environment may be key for de novo engineering of functional tissues from stem cell templates as well as for unraveling the mechanisms underlying multiscale development, growth and adaptation of organisms.

  11. Conserved roles of the prion protein domains on subcellular localization and cell-cell adhesion.

    Directory of Open Access Journals (Sweden)

    Gonzalo P Solis

    Full Text Available Analyses of cultured cells and transgenic mice expressing prion protein (PrP deletion mutants have revealed that some properties of PrP -such as its ability to misfold, aggregate and trigger neurotoxicity- are controlled by discrete molecular determinants within its protein domains. Although the contributions of these determinants to PrP biosynthesis and turnover are relatively well characterized, it is still unclear how they modulate cellular functions of PrP. To address this question, we used two defined activities of PrP as functional readouts: 1 the recruitment of PrP to cell-cell contacts in Drosophila S2 and human MCF-7 epithelial cells, and 2 the induction of PrP embryonic loss- and gain-of-function phenotypes in zebrafish. Our results show that homologous mutations in mouse and zebrafish PrPs similarly affect their subcellular localization patterns as well as their in vitro and in vivo activities. Among PrP's essential features, the N-terminal leader peptide was sufficient to drive targeting of our constructs to cell contact sites, whereas lack of GPI-anchoring and N-glycosylation rendered them inactive by blocking their cell surface expression. Importantly, our data suggest that the ability of PrP to homophilically trans-interact and elicit intracellular signaling is primarily encoded in its globular domain, and modulated by its repetitive domain. Thus, while the latter induces the local accumulation of PrPs at discrete punctae along cell contacts, the former counteracts this effect by promoting the continuous distribution of PrP. In early zebrafish embryos, deletion of either domain significantly impaired PrP's ability to modulate E-cadherin cell adhesion. Altogether, these experiments relate structural features of PrP to its subcellular distribution and in vivo activity. Furthermore, they show that despite their large evolutionary history, the roles of PrP domains and posttranslational modifications are conserved between mouse and

  12. In Situ Spatiotemporal Mapping of Flow Fields around Seeded Stem Cells at the Subcellular Length Scale

    Science.gov (United States)

    Song, Min Jae; Dean, David; Knothe Tate, Melissa L.

    2010-01-01

    A major hurdle to understanding and exploiting interactions between the stem cell and its environment is the lack of a tool for precise delivery of mechanical cues concomitant to observing sub-cellular adaptation of structure. These studies demonstrate the use of microscale particle image velocimetry (μ-PIV) for in situ spatiotemporal mapping of flow fields around mesenchymal stem cells, i.e. murine embryonic multipotent cell line C3H10T1/2, at the subcellular length scale, providing a tool for real time observation and analysis of stem cell adaptation to the prevailing mechanical milieu. In the absence of cells, computational fluid dynamics (CFD) predicts flow regimes within 12% of μ-PIV measures, achieving the technical specifications of the chamber and the flow rates necessary to deliver target shear stresses at a particular height from the base of the flow chamber. However, our μ-PIV studies show that the presence of cells per se as well as the density at which cells are seeded significantly influences local flow fields. Furthermore, for any given cell or cell seeding density, flow regimes vary significantly along the vertical profile of the cell. Hence, the mechanical milieu of the stem cell exposed to shape changing shear stresses, induced by fluid drag, varies with respect to proximity of surrounding cells as well as with respect to apical height. The current study addresses a previously unmet need to predict and observe both flow regimes as well as mechanoadaptation of cells in flow chambers designed to deliver precisely controlled mechanical signals to live cells. An understanding of interactions and adaptation in response to forces at the interface between the surface of the cell and its immediate local environment may be key for de novo engineering of functional tissues from stem cell templates as well as for unraveling the mechanisms underlying multiscale development, growth and adaptation of organisms. PMID:20862249

  13. Precise Photodynamic Therapy of Cancer via Subcellular Dynamic Tracing of Dual-loaded Upconversion Nanophotosensitizers

    National Research Council Canada - National Science Library

    Yulei Chang; Xiaodan Li; Li Zhang; Lu Xia; Xiaomin Liu; Cuixia Li; Youlin Zhang; Langping Tu; Bin Xue; Huiying Zhao; Hong Zhang; Xianggui Kong

    2017-01-01

    ...) light have led to substantial progress in improving photodynamic therapy (PDT) of cancer. For a successful PDT, subcellular organelles are promising therapeutic targets for reaching a satisfactory efficacy...

  14. Intramuscular compartment pressure measurement in chronic exertional compartment syndrome: new and improved diagnostic criteria.

    Science.gov (United States)

    Roscoe, David; Roberts, Andrew J; Hulse, David

    2015-02-01

    Patients with chronic exertional compartment syndrome (CECS) have pain during exercise that subsides with rest. Diagnosis is usually confirmed by intramuscular compartment pressure (IMCP) measurement. Controversy exists regarding the accuracy of existing diagnostic criteria. (1) To compare dynamic IMCP measurement and anthropometric factors between patients with CECS and asymptomatic controls and (2) to establish the diagnostic utility of dynamic IMCP measurement. Cohort study (diagnosis); Level of evidence, 2. A total of 40 men aged 21 to 40 years were included in the study: 20 with symptoms of CECS of the anterior compartment and 20 asymptomatic controls. Diagnoses other than CECS were excluded with rigorous inclusion criteria and magnetic resonance imaging. The IMCP was measured continuously before, during, and after participants exercised on a treadmill, wearing identical footwear and carrying a 15-kg load. Pain experienced by study subjects increased incrementally as the study progressed (P compartment IMCP is elevated immediately upon standing at rest in subjects with CECS. In patients with symptoms consistent with CECS, diagnostic utility of IMCP measurement is improved when measured continuously during exercise. A cutoff of 105 mm Hg in phase 2 provides better diagnostic accuracy than do the Pedowitz criteria of 30 mm Hg and 20 mm Hg at 1 and 5 minutes after exercise, respectively. © 2014 The Author(s).

  15. Role of Repeat Muscle Compartment Pressure Measurements in Chronic Exertional Compartment Syndrome of the Lower Leg

    Science.gov (United States)

    van Zantvoort, Aniek P. M.; de Bruijn, Johan A.; Winkes, Michiel B.; Hoogeveen, Adwin R.; Teijink, Joep A. W.; Scheltinga, Marc R.

    2017-01-01

    Background: The diagnostic gold standard for diagnosing chronic exertional compartment syndrome (CECS) is a dynamic intracompartmental pressure (ICP) measurement of the muscle. The potential role of a repeat ICP (re-ICP) measurement in patients with persistent lower leg symptoms after surgical decompression or with ongoing symptoms after an earlier normal ICP is unknown. Purpose: To study whether re-ICP measurements in patients with persistent CECS-like symptoms of the lower leg may contribute to the diagnosis of CECS after both surgical decompression and a previously normal ICP measurement. Study Design: Case series; Level of evidence, 4. Methods: Charts of patients who underwent re-ICP measurement of lower leg compartments (anterior [ant], deep posterior [dp], and/or lateral [lat] compartments) between 2001 and 2013 were retrospectively studied. CECS was diagnosed on the basis of generally accepted cutoff pressures for newly onset CECS (Pedowitz criteria: ICP at rest ≥15 mmHg, ≥30 mmHg after 1 minute, or ≥20 mmHg 5 minutes after a provocative test). Factors predicting recurrent CECS after surgery or after a previously normal ICP measurement were analyzed. Results: A total of 1714 ICP measurements were taken in 1513 patients with suspected CECS over a 13-year observation period. In all, 201 (12%) tests were re-ICP measurements for persistent lower leg symptoms. Based on the proposed ICP cutoff values, CECS recurrence was diagnosed in 16 of 62 previously operated compartments (recurrence rate, 26%; 53 patients [64% female]; median age, 24 years; age range, 15-78 years). Recurrence rates were not different among the 3 lower leg CECS compartments (ant-CECS, 17%; dp-CECS, 33%; lat-CECS, 30%; χ2 = 1.928, P = .381). Sex (χ2 = 0.058, P = .810), age (U = 378, z = 1.840, P = .066), bilaterality (χ2 = 0.019, P = .889), and prefasciotomy ICP did not predict recurrence. Re-ICP measurements evaluating 20 compartments with previously normal ICP measurements (15

  16. Studies on the subcellular localization of the porphycene CPO.

    Science.gov (United States)

    Kessel, David; Conley, Mary; Vicente, M Graça H; Reiners, John J

    2005-01-01

    This study was designed to provide more detailed information on the subcellular sites of binding of the porphycene, termed 9-capronyloxytetrakis (methoxyethyl) porphycene (CPO), with a fluorescence resonance energy transfer (FRET) technique. The proximity of CPO to two fluorescent probes was determined: nonyl acridine orange (NAO), a dye with specific affinity for the mitochondrial lipid cardiolipin, and dihexa-oxacarbocyanine iodide (DiOC6), an agent that labels the endoplasmic reticulum (ER). FRET spectra indicated energy transfer between DiOC6 and CPO but no significant transfer between NAO and CPO. These results confirm data obtained by fluorescence microscopy, suggesting a similar pattern of subcellular localization by CPO and DiOC6 but not by CPO and NAO. However, when cells containing CPO were irradiated and then loaded with NAO, FRET between the two fluorophores was observed. Hence, a relocalization of CPO can occur during irradiation. These data provide an explanation for recent studies on CPO-catalyzed photodamage to both ER and mitochondrial Bcl-2.

  17. Studies on the Subcellular Localization of the Porphycene CPO¶

    Science.gov (United States)

    Kessel, David; Conley, Mary; Vicente, M. Graça H.; Reiners, John J.

    2010-01-01

    This study was designed to provide more detailed information on the subcellular sites of binding of the porphycene, termed 9-capronyloxytetrakis (methoxyethyl) porphycene (CPO), with a fluorescence resonance energy transfer (FRET) technique. The proximity of CPO to two fluorescent probes was determined: nonyl acridine orange (NAO), a dye with specific affinity for the mitochondrial lipid cardiolipin, and dihexaoxacarbocyanine iodide (DiOC6), an agent that labels the endoplasmic reticulum (ER). FRET spectra indicated energy transfer between DiOC6 and CPO but no significant transfer between NAO and CPO. These results confirm data obtained by fluorescence microscopy, suggesting a similar pattern of subcellular localization by CPO and DiOC6 but not by CPO and NAO. However, when cells containing CPO were irradiated and then loaded with NAO, FRET between the two fluorophores was observed. Hence, a relocalization of CPO can occur during irradiation. These data provide an explanation for recent studies on CPO-catalyzed photodamage to both ER and mitochondrial Bcl-2. PMID:15745423

  18. Gene ontology based transfer learning for protein subcellular localization

    Directory of Open Access Journals (Sweden)

    Zhou Shuigeng

    2011-02-01

    Full Text Available Abstract Background Prediction of protein subcellular localization generally involves many complex factors, and using only one or two aspects of data information may not tell the true story. For this reason, some recent predictive models are deliberately designed to integrate multiple heterogeneous data sources for exploiting multi-aspect protein feature information. Gene ontology, hereinafter referred to as GO, uses a controlled vocabulary to depict biological molecules or gene products in terms of biological process, molecular function and cellular component. With the rapid expansion of annotated protein sequences, gene ontology has become a general protein feature that can be used to construct predictive models in computational biology. Existing models generally either concatenated the GO terms into a flat binary vector or applied majority-vote based ensemble learning for protein subcellular localization, both of which can not estimate the individual discriminative abilities of the three aspects of gene ontology. Results In this paper, we propose a Gene Ontology Based Transfer Learning Model (GO-TLM for large-scale protein subcellular localization. The model transfers the signature-based homologous GO terms to the target proteins, and further constructs a reliable learning system to reduce the adverse affect of the potential false GO terms that are resulted from evolutionary divergence. We derive three GO kernels from the three aspects of gene ontology to measure the GO similarity of two proteins, and derive two other spectrum kernels to measure the similarity of two protein sequences. We use simple non-parametric cross validation to explicitly weigh the discriminative abilities of the five kernels, such that the time & space computational complexities are greatly reduced when compared to the complicated semi-definite programming and semi-indefinite linear programming. The five kernels are then linearly merged into one single kernel for

  19. Application of green fluorescent protein-labeled assay for the study of subcellular localization of Newcastle disease virus matrix protein.

    Science.gov (United States)

    Duan, Zhiqiang; Li, Qunhui; He, Liang; Zhao, Guo; Chen, Jian; Hu, Shunlin; Liu, Xiufan

    2013-12-01

    Green fluorescent protein (GFP) used as a powerful marker of gene expression in vivo has so far been applied widely in studying the localizations and functions of protein in living cells. In this study, GFP-labeled assay was used to investigate the subcellular localization of matrix (M) protein of different virulence and genotype Newcastle disease virus (NDV) strains. The M protein of ten NDV strains fused with GFP (GFP-M) all showed nuclear-and-nucleolar localization throughout transfection, whereas that of the other two strains were observed in the nucleus and nucleolus early in transfection but in the cytoplasm late in transfection. In addition, mutations to the previously defined nuclear localization signal in the GFP-M fusion protein were studied as well. Single changes at positions 262 and 263 did not affect nuclear localization of M, while changing both of these arginine residues to asparagine caused re-localization of M mainly to the cytoplasm. The GFP-M was validated as a suitable system for studying the subcellular localization of M protein and could be used to assist us in further identifying the signal sequences responsible for the nucleolar localization and cytoplasmic localization of M protein. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. An experimental study on crib fires in a closed compartment

    Directory of Open Access Journals (Sweden)

    Dhurandher Bhisham Kumar

    2017-01-01

    Full Text Available An experimental investigation on burning behavior of fire in closed compartments is presented. Fire experiments were performed in a closed compartment of interior dimensions 4 × 4 × 4 m (length × width × height with ply board cribs as fire source. The parameters including the gas temperature, mass loss rate, heat flux, flame temperature, and compartment pressure were measured during the experiments. Experimental results indicated that the providing sudden ventilation to the closed compartment had great influence on the behavior of fire. The mass loss rate of the burning crib increased by 150% due to sudden ventilation which results in the increase in heat release rate by 198 kW. From the perspective of total heat flux, compartment pressure, and gas temperatures closed compartment with sudden ventilation were more hazardous.

  1. Spatial organization of Hippo signaling at the plasma membrane mediated by the tumor suppressor Merlin/NF2.

    Science.gov (United States)

    Yin, Feng; Yu, Jianzhong; Zheng, Yonggang; Chen, Qian; Zhang, Nailing; Pan, Duojia

    2013-09-12

    Although Merlin/NF2 was discovered two decades ago as a tumor suppressor underlying Neurofibromatosis type II, its precise molecular mechanism remains poorly understood. Recent studies in Drosophila revealed a potential link between Merlin and the Hippo pathway by placing Merlin genetically upstream of the kinase Hpo/Mst. In contrast to the commonly depicted linear model of Merlin functioning through Hpo/Mst, here we show that in both Drosophila and mammals, Merlin promotes downstream Hippo signaling without activating the intrinsic kinase activity of Hpo/Mst. Instead, Merlin directly binds and recruits the effector kinase Wts/Lats to the plasma membrane. Membrane recruitment, in turn, promotes Wts phosphorylation by the Hpo-Sav kinase complex. We further show that disruption of the actin cytoskeleton promotes Merlin-Wts interactions, which implicates Merlin in actin-mediated regulation of Hippo signaling. Our findings elucidate an important molecular function of Merlin and highlight the plasma membrane as a critical subcellular compartment for Hippo signal transduction. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Modeling malware propagation using a carrier compartment

    Science.gov (United States)

    Hernández Guillén, J. D.; Martín del Rey, A.

    2018-03-01

    The great majority of mathematical models proposed to simulate malware spreading are based on systems of ordinary differential equations. These are compartmental models where the devices are classified according to some types: susceptible, exposed, infectious, recovered, etc. As far as we know, there is not any model considering the special class of carrier devices. This type is constituted by the devices whose operative systems is not targeted by the malware (for example, iOS devices for Android malware). In this work a novel mathematical model considering this new compartment is considered. Its qualitative study is presented and a detailed analysis of the efficient control measures is shown by studying the basic reproductive number.

  3. The upper hand on compartment syndrome.

    LENUS (Irish Health Repository)

    Dolan, Roisin T

    2012-11-01

    Metacarpal fractures are common injuries, accounting for approximately 30% to 40% of all hand fractures and with a lifetime incidence of 2.5%. Traditionally regarded as an innocuous injury, metacarpal fractures tend to be associated with successful outcomes after closed reduction and immobilization. Hand compartment syndrome (HCS) is a rare clinical entity with potential devastating consequences in terms of loss of function and quality-of-life outcomes. We discuss the case of a 44-year-old woman presenting with multiple closed metacarpal fractures as a result of low-energy trauma, complicated by acute HCS. We review the presentation, clinical assessment, and optimal surgical management of acute HCS with reference to international literature.

  4. Compartment syndrome can also be seen in the forearm

    DEFF Research Database (Denmark)

    Asmar, Ali; Broholm, Rikke; Bülow, Jens

    2014-01-01

    Chronic compartment syndrome is a challenge for the clinician and symptomatic similar to neuropathies, tenosynovitis, stress fractures and referred pain from lumbar cervicalis. Thus, chronic compartment syndrome of the upper extremities is probably an underdiagnosed condition. In patients...... with stress-induced pain in the upper limbs, chronic compartment syndrome should be considered - particularly in young patients with high physical activity. Despite limited literature, the effect of surgical treatment is promising....

  5. Dynamic Compartments in the Imperative π-Calculus

    Science.gov (United States)

    John, Mathias; Lhoussaine, Cédric; Niehren, Joachim

    Dynamic compartments with mutable configurations and variable volumes are of basic interest for the stochastic modeling of biochemistry in cells. We propose a new language to express dynamic compartments that we call the imperative π -calculus. It is obtained from the attributed π -calculus by adding imperative assignment operations to a global store. Previous approaches to dynamic compartments are improved in flexibility or efficiency. This is illustrated by an appropriate model of osmosis and a correct encoding of bioambBioAmbients.

  6. Coping with the diagnostic complexities of the compartment syndrome

    Science.gov (United States)

    Mubarak, S. J.; Hargens, A. R.; Karkal, S. S.

    1988-01-01

    This review recognizes that, given the various complexities associated with the condition, no pat answers can be given to fit every patient with the compartment syndrome. The authors first give a definition of the syndrome, together with a brief account of how this self-perpetuating pathologic cycle is triggered. Next, they delineate specific anatomical features of compartments that are likely to be involved, and follow this with an inventory of symptoms and signs to look for in suspected cases. After sorting out the entities that can mimic the compartment syndrome, the authors describe three essential techniques of measuring tissue pressure, which can prove invaluable in diagnosing the compartment syndrome.

  7. Lateral canthotomy and cantholysis: emergency management of orbital compartment syndrome.

    Science.gov (United States)

    Rowh, Adam D; Ufberg, Jacob W; Chan, Theodore C; Vilke, Gary M; Harrigan, Richard A

    2015-03-01

    Orbital compartment syndrome is a sight-threatening emergency. Vision may be preserved when timely intervention is performed. To present a case of orbital compartment syndrome caused by traumatic retrobulbar hemorrhage and the procedure of lateral canthotomy and cantholysis, reviewed with photographic illustration. Lateral canthotomy and cantholysis are readily performed at the bedside with simple instruments. The procedure may prevent irreversible blindness in cases of acute orbital compartment syndrome. Emergency physicians should be familiar with lateral canthotomy and cantholysis in the management of orbital compartment syndrome to minimize the chance of irreversible visual loss. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Compartment Syndrome After Varicose Vein Surgery Evidenced by CT Images.

    Science.gov (United States)

    Wang, Sheng-Min; Kim, Maru

    2016-03-01

    A 21-year-old man developed compartment syndrome after a varicose vein surgery. Because of a lack of appropriate diagnostic apparatus, it was not possible to measure calf pressure. The only diagnostic tool available was computed tomography (CT). With the aid of CT, faster diagnosis of the compartment syndrome was possible, leading to appropriate management. By providing unique CT images of a patient before and after having compartment syndrome and after a fasciotomy, this study could add valuable references for diagnosis of compartment syndrome using CT. © The Author(s) 2014.

  9. Acute compartment syndrome in lower extremity musculoskeletal trauma.

    Science.gov (United States)

    Olson, Steven A; Glasgow, Robert R

    2005-11-01

    Acute compartment syndrome is a potentially devastating condition in which the pressure within an osseofascial compartment rises to a level that decreases the perfusion gradient across tissue capillary beds, leading to cellular anoxia, muscle ischemia, and death. A variety of injuries and medical conditions may initiate acute compartment syndrome, including fractures, contusions, bleeding disorders, burns, trauma, postischemic swelling, and gunshot wounds. Diagnosis is primarily clinical, supplemented by compartment pressure measurements. Certain anesthetic techniques, such as nerve blocks and other forms of regional and epidural anesthesia, reportedly contribute to a delay in diagnosis. Basic science data suggest that the ischemic threshold of normal muscle is reached when pressure within the compartment is elevated to 20 mm Hg below the diastolic pressure or 30 mm Hg below the mean arterial blood pressure. On diagnosis of impending or true compartment syndrome, immediate measures must be taken. Complete fasciotomy of all compartments involved is required to reliably normalize compartment pressures and restore perfusion to the affected tissues. Recognizing compartment syndromes requires having and maintaining a high index of suspicion, performing serial examinations in patients at risk, and carefully documenting changes over time.

  10. Targeting and localized signalling by small GTPases

    NARCIS (Netherlands)

    ten Klooster, Jean Paul; Hordijk, Peter L.

    2007-01-01

    Polarized cellular responses, for example, cell migration, require the co-ordinated assembly of signalling complexes at a particular subcellular location, such as the leading edge of cells. Small GTPases of the Ras superfamily play central roles in many (polarized) responses to growth factors,

  11. Distribution and Characterization of Antigens Found in Subcellular Fractions of African Trypanosomes.

    Science.gov (United States)

    1979-08-01

    Islation of bodies % containing the cyanide insensitive glycerophosphate oxidase of Trypanosoma - equiperdum . Comp. Biochem. Physiol. 30 1049-1054. S...commenced on a project aimed at characterizing the subcellular distribution and nature of antigens found in the African trypanosome, Trypanosoma rhodesiense...current project concerning the subcellular distribution and characterization of antigens in the African trypanosome, Trypanosoma rhodesiense. During

  12. Genetically encoded fluorescent indicator for imaging NAD(+)/NADH ratio changes in different cellular compartments.

    Science.gov (United States)

    Bilan, Dmitry S; Matlashov, Mikhail E; Gorokhovatsky, Andrey Yu; Schultz, Carsten; Enikolopov, Grigori; Belousov, Vsevolod V

    2014-03-01

    The ratio of NAD(+)/NADH is a key indicator that reflects the overall redox state of the cells. Until recently, there were no methods for real time NAD(+)/NADH monitoring in living cells. Genetically encoded fluorescent probes for NAD(+)/NADH are fundamentally new approach for studying the NAD(+)/NADH dynamics. We developed a genetically encoded probe for the nicotinamide adenine dinucleotide, NAD(H), redox state changes by inserting circularly permuted YFP into redox sensor T-REX from Thermus aquaticus. We characterized the sensor in vitro using spectrofluorometry and in cultured mammalian cells using confocal fluorescent microscopy. The sensor, named RexYFP, reports changes in the NAD(+)/NADH ratio in different compartments of living cells. Using RexYFP, we were able to track changes in NAD(+)/NADH in cytoplasm and mitochondrial matrix of cells under a variety of conditions. The affinity of the probe enables comparison of NAD(+)/NADH in compartments with low (cytoplasm) and high (mitochondria) NADH concentration. We developed a method of eliminating pH-driven artifacts by normalizing the signal to the signal of the pH sensor with the same chromophore. RexYFP is suitable for detecting the NAD(H) redox state in different cellular compartments. RexYFP has several advantages over existing NAD(+)/NADH sensors such as smallest size and optimal affinity for different compartments. Our results show that normalizing the signal of the sensor to the pH changes is a good strategy for overcoming pH-induced artifacts in imaging. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Engineering metal-binding sites of bacterial CusF to enhance Zn/Cd accumulation and resistance by subcellular targeting

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Pengli; Yuan, Jinhong [Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093 (China); Zhang, Hui [Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093 (China); Deng, Xin [Department of Chemistry and Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL 60637 (United States); Ma, Mi [Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093 (China); Zhang, Haiyan, E-mail: hyz@ibcas.ac.cn [Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093 (China)

    2016-01-25

    Highlights: • mCusF is specifically targeted to different subcellular compartments in Arabidopsis. • Plants expressing vacuole-targeted mCusF exhibit strongest Zn resistance. • All transgenic lines accumulate more Zn under Zn exposure. • All transgenic lines enhance root-to-shoot translocation of Cd. • Metal homeostasis is improved in mCusF plants under Cd exposure. - Abstract: The periplasmic protein CusF acts as a metallochaperone to mediate Cu resistance in Escherichia coli. CusF does not contain cysteine residues and barely binds to divalent cations. Here, we addressed effects of cysteine-substitution mutant (named as mCusF) of CusF on zinc/cadmium (Zn/Cd) accumulation and resistance. We targeted mCusF to different subcellular compartments in Arabidopsis. We found that plants expressing vacuole-targeted mCusF were more resistant to excess Zn than WT and plants with cell wall-targeted or cytoplasmic mCusF. Under long-term exposure to excess Zn, all transgenic lines accumulated more Zn (up to 2.3-fold) in shoots than the untransformed plants. Importantly, plants with cytoplasmic mCusF showed higher efficiency of Zn translocation from root to shoot than plants with secretory pathway-targeted-mCusF. Furthermore, the transgenic lines exhibited enhanced resistance to Cd and significant increase in root-to-shoot Cd translocation. We also found all transgenic plants greatly improved manganese (Mn) and iron (Fe) homeostasis under Cd exposure. Our results demonstrate heterologous expression of mCusF could be used to engineer a new phytoremediation strategy for Zn/Cd and our finding also deepen our insights into mechanistic basis for relieving Cd toxicity in plants through proper root/shoot partitioning mechanism and homeostatic accumulation of Mn and Fe.

  14. Dynamic subcellular localization of a respiratory complex controls bacterial respiration.

    Science.gov (United States)

    Alberge, François; Espinosa, Leon; Seduk, Farida; Sylvi, Léa; Toci, René; Walburger, Anne; Magalon, Axel

    2015-06-16

    Respiration, an essential process for most organisms, has to optimally respond to changes in the metabolic demand or the environmental conditions. The branched character of their respiratory chains allows bacteria to do so by providing a great metabolic and regulatory flexibility. Here, we show that the native localization of the nitrate reductase, a major respiratory complex under anaerobiosis in Escherichia coli, is submitted to tight spatiotemporal regulation in response to metabolic conditions via a mechanism using the transmembrane proton gradient as a cue for polar localization. These dynamics are critical for controlling the activity of nitrate reductase, as the formation of polar assemblies potentiates the electron flux through the complex. Thus, dynamic subcellular localization emerges as a critical factor in the control of respiration in bacteria.

  15. Targeting a heterologous protein to multiple plant organelles via rationally designed 5? mRNA tags

    NARCIS (Netherlands)

    Voges, M.J.; Silver, P.A.; Way, J.C.; Mattozzi, M.D.

    2013-01-01

    Background Plant bioengineers require simple genetic devices for predictable localization of heterologous proteins to multiple subcellular compartments. Results We designed novel hybrid signal sequences for multiple-compartment localization and characterize their function when fused to GFP in

  16. Cellular and subcellular localization of Marlin-1 in the brain

    Directory of Open Access Journals (Sweden)

    Luján Rafael

    2009-04-01

    Full Text Available Abstract Background Marlin-1 is a microtubule binding protein that associates specifically with the GABAB1 subunit in neurons and with members of the Janus kinase family in lymphoid cells. In addition, it binds the molecular motor kinesin-I and nucleic acids, preferentially single stranded RNA. Marlin-1 is expressed mainly in the central nervous system but little is known regarding its cellular and subcellular distribution in the brain. Results Here we have studied the localization of Marlin-1 in the rodent brain and cultured neurons combining immunohistochemistry, immunofluorescence and pre-embedding electron microscopy. We demonstrate that Marlin-1 is enriched in restricted areas of the brain including olfactory bulb, cerebral cortex, hippocampus and cerebellum. Marlin-1 is abundant in dendrites and axons of GABAergic and non-GABAergic hippocampal neurons. At the ultrastructural level, Marlin-1 is present in the cytoplasm and the nucleus of CA1 neurons in the hippocampus. In the cytoplasm it associates to microtubules in the dendritic shaft and occasionally with the Golgi apparatus, the endoplasmic reticulum (ER and dendritic spines. In the nucleus, clusters of Marlin-1 associate to euchromatin. Conclusion Our results demonstrate that Marlin-1 is expressed in discrete areas of the brain. They also confirm the microtubule association at the ultrastructural level in neurons. Together with the abundance of the protein in dendrites and axons they are consistent with the emerging role of Marlin-1 as an intracellular protein linking the cytoskeleton and transport. Our study constitutes the first detailed description of the cellular and subcellular distribution of Marlin-1 in the brain. As such, it will set the basis for future studies on the functional implications of Marlin-1 in protein trafficking.

  17. Cellular and subcellular localization of Marlin-1 in the brain.

    Science.gov (United States)

    Vidal, René L; Valenzuela, José I; Luján, Rafael; Couve, Andrés

    2009-04-22

    Marlin-1 is a microtubule binding protein that associates specifically with the GABAB1 subunit in neurons and with members of the Janus kinase family in lymphoid cells. In addition, it binds the molecular motor kinesin-I and nucleic acids, preferentially single stranded RNA. Marlin-1 is expressed mainly in the central nervous system but little is known regarding its cellular and subcellular distribution in the brain. Here we have studied the localization of Marlin-1 in the rodent brain and cultured neurons combining immunohistochemistry, immunofluorescence and pre-embedding electron microscopy. We demonstrate that Marlin-1 is enriched in restricted areas of the brain including olfactory bulb, cerebral cortex, hippocampus and cerebellum. Marlin-1 is abundant in dendrites and axons of GABAergic and non-GABAergic hippocampal neurons. At the ultrastructural level, Marlin-1 is present in the cytoplasm and the nucleus of CA1 neurons in the hippocampus. In the cytoplasm it associates to microtubules in the dendritic shaft and occasionally with the Golgi apparatus, the endoplasmic reticulum (ER) and dendritic spines. In the nucleus, clusters of Marlin-1 associate to euchromatin. Our results demonstrate that Marlin-1 is expressed in discrete areas of the brain. They also confirm the microtubule association at the ultrastructural level in neurons. Together with the abundance of the protein in dendrites and axons they are consistent with the emerging role of Marlin-1 as an intracellular protein linking the cytoskeleton and transport. Our study constitutes the first detailed description of the cellular and subcellular distribution of Marlin-1 in the brain. As such, it will set the basis for future studies on the functional implications of Marlin-1 in protein trafficking.

  18. Subcellular distribution and chemical forms of antimony in Ficus tikoua.

    Science.gov (United States)

    Wang, Yong; Chai, Liyuan; Yang, Zhihui; Mubarak, Hussani; Xiao, Ruiyang; Tang, Chongjian

    2017-02-01

    Ficus tikoua (F. tikoua) was a potential species for antimony (Sb) phytoremediation due to its wide growth in the mining area. However, little was known about its tolerance mechanisms toward Sb. The determination of the distribution and chemical speciation of Sb in F. tikoua is essential for understanding the mechanisms involved in Sb accumulation, transportation, and detoxification. The present study investigated the subcellular distribution and chemical forms of Sb in F. tikoua. The plant was exposed to different Sb concentrations (0, 30, 90, and 180 μmol/L) for 30 days. The results showed that F. tikoua possessed a marked ability to tolerate and accumulate Sb. The proportional Sb increased with increasing Sb concentration in the solution, and the highest Sb concentration occurred in roots (1274.5-1580.9 mg/kg), followed by stems (133.5-498.9 mg/kg) and leaves (4.1-15.7 mg/kg). In the subcellular sequestration of Sb in F. tikoua, the largest accumulation of Sb occurred in cell walls (72.4-87.5%) followed by cytoplasmic organelles (8.2-18.6%) and cytoplasmic supernatant. The results suggested that cell walls act as important protective barriers against Sb toxicity in F. tikoua. Although Sb in all plant tissues found primarily in the fractions extracted by ethanol and distilled water, the current study found that the Sb amounts in the HAc-extractable fraction, HCl-extractable fraction, and residue fraction increased at the highest Sb level (180 μmol/L) compared to that under lower Sb levels. These results indicate that excessive Sb accumulated in F. tikoua under Sb stress is bound to non-dissolved or low-bioavailable compounds, a biochemical mechanism that benefits F. tikoua because it helps alleviate Sb toxicity.

  19. Laserspritzer: a simple method for optogenetic investigation with subcellular resolutions.

    Science.gov (United States)

    Sun, Qian-Quan; Wang, Xinjun; Yang, Weiguo

    2014-01-01

    To build a detailed circuit diagram in the brain, one needs to measure functional synaptic connections between specific types of neurons. A high-resolution circuit diagram should provide detailed information at subcellular levels such as soma, distal and basal dendrites. However, a limitation lies in the difficulty of studying long-range connections between brain areas separated by millimeters. Brain slice preparations have been widely used to help understand circuit wiring within specific brain regions. The challenge exists because long-range connections are likely to be cut in a brain slice. The optogenetic approach overcomes these limitations, as channelrhodopsin 2 (ChR2) is efficiently transported to axon terminals that can be stimulated in brain slices. Here, we developed a novel fiber optic based simple method of optogenetic stimulation: the laserspritzer approach. This method facilitates the study of both long-range and local circuits within brain slice preparations. This is a convenient and low cost approach that can be easily integrated with a slice electrophysiology setup, and repeatedly used upon initial validation. Our data with direct ChR2 mediated-current recordings demonstrates that the spatial resolution of the laserspritzer is correlated with the size of the laserspritzer, and the resolution lies within the 30 µm range for the 5 micrometer laserspritzer. Using olfactory cortical slices, we demonstrated that the laserspritzer approach can be applied to selectively activate monosynaptic perisomatic GABAergic basket synapses, or long-range intracortical glutamatergic inputs formed on different subcellular domains within the same cell (e.g. distal and proximal dendrites). We discuss significant advantages of the laserspritzer approach over the widely used collimated LED whole-field illumination method in brain slice electrophysiological research.

  20. Laserspritzer: a simple method for optogenetic investigation with subcellular resolutions.

    Directory of Open Access Journals (Sweden)

    Qian-Quan Sun

    Full Text Available To build a detailed circuit diagram in the brain, one needs to measure functional synaptic connections between specific types of neurons. A high-resolution circuit diagram should provide detailed information at subcellular levels such as soma, distal and basal dendrites. However, a limitation lies in the difficulty of studying long-range connections between brain areas separated by millimeters. Brain slice preparations have been widely used to help understand circuit wiring within specific brain regions. The challenge exists because long-range connections are likely to be cut in a brain slice. The optogenetic approach overcomes these limitations, as channelrhodopsin 2 (ChR2 is efficiently transported to axon terminals that can be stimulated in brain slices. Here, we developed a novel fiber optic based simple method of optogenetic stimulation: the laserspritzer approach. This method facilitates the study of both long-range and local circuits within brain slice preparations. This is a convenient and low cost approach that can be easily integrated with a slice electrophysiology setup, and repeatedly used upon initial validation. Our data with direct ChR2 mediated-current recordings demonstrates that the spatial resolution of the laserspritzer is correlated with the size of the laserspritzer, and the resolution lies within the 30 µm range for the 5 micrometer laserspritzer. Using olfactory cortical slices, we demonstrated that the laserspritzer approach can be applied to selectively activate monosynaptic perisomatic GABAergic basket synapses, or long-range intracortical glutamatergic inputs formed on different subcellular domains within the same cell (e.g. distal and proximal dendrites. We discuss significant advantages of the laserspritzer approach over the widely used collimated LED whole-field illumination method in brain slice electrophysiological research.

  1. Subcellular distribution of glutathione and cysteine in cyanobacteria

    Science.gov (United States)

    Tomašić, Ana; Horvat, Lucija; Fulgosi, Hrvoje

    2010-01-01

    Glutathione plays numerous important functions in eukaryotic and prokaryotic cells. Whereas it can be found in virtually all eukaryotic cells, its production in prokaryotes is restricted to cyanobacteria and proteobacteria and a few strains of gram-positive bacteria. In bacteria, it is involved in the protection against reactive oxygen species (ROS), osmotic shock, acidic conditions, toxic chemicals, and heavy metals. Glutathione synthesis in bacteria takes place in two steps out of cysteine, glutamate, and glycine. Cysteine is the limiting factor for glutathione biosynthesis which can be especially crucial for cyanobacteria, which rely on both the sufficient sulfur supply from the growth media and on the protection of glutathione against ROS that are produced during photosynthesis. In this study, we report a method that allows detection and visualization of the subcellular distribution of glutathione in Synechocystis sp. This method is based on immunogold cytochemistry with glutathione and cysteine antisera and computer-supported transmission electron microscopy. Labeling of glutathione and cysteine was restricted to the cytosol and interthylakoidal spaces. Glutathione and cysteine could not be detected in carboxysomes, cyanophycin granules, cell walls, intrathylakoidal spaces, periplasm, and vacuoles. The accuracy of the glutathione and cysteine labeling is supported by two observations. First, preadsorption of the antiglutathione and anticysteine antisera with glutathione and cysteine, respectively, reduced the density of the gold particles to background levels. Second, labeling of glutathione and cysteine was strongly decreased by 98.5% and 100%, respectively, in Synechocystis sp. cells grown on media without sulfur. This study indicates a strong similarity of the subcellular distribution of glutathione and cysteine in cyanobacteria and plastids of plants and provides a deeper insight into glutathione metabolism in bacteria. PMID:20349253

  2. Arginine Methylation Controls the Subcellular Localization and Functions of the Oncoprotein Splicing Factor SF2/ASF▿ †

    Science.gov (United States)

    Sinha, Rahul; Allemand, Eric; Zhang, Zuo; Karni, Rotem; Myers, Michael P.; Krainer, Adrian R.

    2010-01-01

    Alternative splicing and posttranslational modifications (PTMs) are major sources of protein diversity in eukaryotic proteomes. The SR protein SF2/ASF is an oncoprotein that functions in pre-mRNA splicing, with additional roles in other posttranscriptional and translational events. Functional studies of SR protein PTMs have focused exclusively on the reversible phosphorylation of Ser residues in the C-terminal RS domain. We confirmed that human SF2/ASF is methylated at residues R93, R97, and R109, which were identified in a global proteomic analysis of Arg methylation, and further investigated whether these methylated residues regulate the properties of SF2/ASF. We show that the three arginines additively control the subcellular localization of SF2/ASF and that both the positive charge and the methylation state are important. Mutations that block methylation and remove the positive charge result in the cytoplasmic accumulation of SF2/ASF. The consequent decrease in nuclear SF2/ASF levels prevents it from modulating the alternative splicing of target genes, results in higher translation stimulation, and abrogates the enhancement of nonsense-mediated mRNA decay. This study addresses the mechanisms by which Arg methylation and the associated positive charge regulate the activities of SF2/ASF and emphasizes the significance of localization control for an oncoprotein with multiple functions in different cellular compartments. PMID:20308322

  3. Molecular cloning, subcellular localization and characterization of two adenylate kinases from cassava, Manihot esculenta Crantz cv. KU50.

    Science.gov (United States)

    Boonrueng, Channarong; Tangpranomkorn, Surachat; Yazhisai, Uthaman; Sirikantaramas, Supaart

    2016-10-01

    Adenylate kinase (ADK) is a phosphotransferase that plays an important role in cellular energy homeostasis. Many isozymes located in different subcellular compartments have been reported. In this study, we focus on the characterization of cassava (Manihot esculenta) ADKs. We found 15 ADKs that are publicly available in the African cassava genome database. We cloned two ADKs, namely MeADK1 and MeADK2, which are phylogenetically grouped together with the plastidial ADK in potato. Both MeADK1 and MeADK2 showed 66% identity in the amino acid sequences with plastidial ADK in potato. However, we demonstrated that they are localized to mitochondria using GFP fusions of MeADK1 and MeADK2. The Escherichia coli-produced recombinant MeADK1 and MeADK2 preferred forward reactions that produce ATP. They exhibited similar specific activities. The semi-quantitative RT-PCR analysis showed that MeADK1 and MeADK2 in 2-month-old leaves have similar expression patterns under a diurnal light-dark cycle. However, MeADK2 transcripts were expressed at much higher levels than MeADK1 in 5-month-old leaves and roots. Thus, we conclude that MeADK2 might play a vital role in energy homeostasis in cassava mitochondria. Copyright © 2016 Elsevier GmbH. All rights reserved.

  4. The compartmented alginate fibres optimisation for bitumen rejuvenator encapsulation

    NARCIS (Netherlands)

    Tabaković, Amir; Copuroglu, O.; Post, W.; Garcia Espallargas, Santiago J.; Schlangen, H.E.J.G.

    2017-01-01

    This article presents development of a novel self-healing technology for asphalt pavements, where asphalt binder rejuvenator is encapsulated within the compartmented alginate fibres. The key objective of the study was to optimise the compartmented alginate fibre design, i.e., maximising amount of

  5. Radiographic predictors of compartment syndrome in tibial plateau fractures.

    Science.gov (United States)

    Ziran, Bruce H; Becher, Stephen John

    2013-11-01

    The purpose of this article was to evaluate the relationship of radiographic features of tibial plateau fractures to the development of compartment syndrome. We hypothesized that the direction and degree of initial displacement of the femur on the tibia, and the amount of tibial widening (TW), were correlated with the development of compartment syndrome. Retrospective case-control study. Single level 1 trauma center. Retrospective evaluation of 158 patients with 162 plateau fractures. Grouping with and without compartment syndrome. The following data were obtained: age, sex, Schatzker and OTA/AO classification, open/closed status, TW, and femoral displacement (FD). A univariate statistical and a logistical regression analysis were performed to determine significance. The overall rate of compartment syndrome was 11%. Univariate analysis found both the TW and FD to be significant with respect to development of compartment syndrome (P compartment syndrome. Logistic regression found FD and Schatzker grade to be significant. Our study is the first to identify easily obtained radiographic parameters that correlate to the occurrence compartment syndrome. There may also be a relationship between TW and FD, as noted by regression result. This study helps to assess which patients with a fracture are at higher risk for developing a compartment syndrome. Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

  6. Chronic Exertional Compartment Syndrome in a Healthy Young Man.

    Science.gov (United States)

    Joubert, Sonia V; Duarte, Manuel A

    2016-06-01

    The purpose of this case report is to describe a patient who presented with symptoms of exercise-induced compartment syndrome and was later referred for bilateral fasciotomy surgery. A 21-year-old patient presented for chiropractic care with the inability to run due to foot paresthesia and weakness. An exertion test and compartment pressure test diagnosed exercise-induced compartment syndrome. Exertion test and compartment pressure test were used to identify and diagnose exercise-induced compartment syndrome. The patient was diagnosed with exercise-induced compartment syndrome. He was treated conservatively and referred for additional testing. The orthopedic surgeon requested that 12 weeks of conservative care be provided prior to testing; treatment consisted of chiropractic care and rehabilitation exercises. Following the 12 weeks of treatment, the patient did not significantly respond to conservative care. A compartment pressure test confirmed the initial diagnosis of exercise-induced compartment syndrome. The patient underwent a unilateral fasciotomy surgery and recovered fully. Following the surgery, the patient returned to the chiropractic clinic with the same presentation in the contralateral leg. The same protocol of management resulted in the same outcome. Two years after surgical intervention, the patient continues to maintain an active lifestyle, able to run 2 to 3 miles per day without any exacerbations or symptomatology. Clinical awareness, a detailed history, and thorough examination with reproduction of symptomatology are necessary to form a proper diagnosis and treatment plan for these patients. Therefore, multidisciplinary medical communication would prove to be the most beneficial approach for the patient.

  7. Spontaneous Compartment Syndrome of the Hand in Systemic Sclerosis.

    Science.gov (United States)

    Tanagho, Andy; Hatab, Sameh; Youssef, Sally; Ansara, Sameh

    2015-09-01

    Compartment syndrome refers to a condition of compromised circulation within a limited space due to increased pressure within that space. The reduced tissue perfusion results in reduced venous drainage, leading to increased interstitial tissue pressure and subsequent compromised arterial flow. Although not as common as compartment syndrome of the leg and forearm, compartment syndrome of the hand is not rare and can lead to devastating sequelae as a result of tissue necrosis. Compartment syndrome of the hand has several etiologies, including trauma, arterial injury, thermal injury, and constrictive bandaging. The cardinal clinical sign is pain that is aggravated by passive stretching of the muscles within the involved compartments. Extremity function is usually restored with expeditious fasciotomy of the involved myofascial compartments, and complications, such as intrinsic muscular dysfunction and Volkmann's ischemic contracture, can usually be prevented. There are no reported cases of compartment syndrome of the hand in patients with systemic sclerosis or Raynaud's phenomenon. Systemic sclerosis is a form of scleroderma that affects the skin and internal organs. The limited cutaneous subset affects the skin of the extremities but is associated with a set of characteristic features that includes calcinosis, Raynaud's phenomenon, esophageal involvement, sclerodactyly, and telangiectasia. This report describes an unusual case of a patient who had spontaneous compartment syndrome of the hand. The patient's concomitant limited cutaneous systemic sclerosis may have played a role in this unusual occurrence. The diagnosis was based on the clinical picture, and the symptoms resolved after surgical decompression. Copyright 2015, SLACK Incorporated.

  8. A case of delayed presentation of thigh compartment syndrome.

    Science.gov (United States)

    Wardi, Gabriel; Görtz, Simon; Snyder, Brian

    2014-05-01

    Thigh compartment syndrome is a rare and devastating process. It generally occurs within hours to days of a traumatic event, although cases have been reported nearly 2 weeks after the initial event. To evaluate the literature describing the timing between inciting event and presentation of thigh compartment syndromes, with a focus on delayed presentations of this rare condition. To describe the unique properties of thigh compartments, and finally, to review the anatomy and techniques needed to measure the compartment pressures of the thigh. A case of a 54-year-old man is presented. He sustained trauma to his thigh 17 days prior to presenting to our ED with severe, sudden-onset pain in his right thigh. Compartment pressures were measured and confirmed the diagnosis of compartment syndrome caused by two large intramuscular hematomas. No other contributing events were identified. Compartment syndrome in the thigh should be considered in patients with a concerning examination and a history of recent trauma. This particular case represents the longest reported time between injury and development of a thigh compartment syndrome. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Mannitol extravasation during partial nephrectomy leading to forearm compartment syndrome

    Directory of Open Access Journals (Sweden)

    Bradley A. Erickson

    2007-02-01

    Full Text Available We present the first known complication of forearm compartment syndrome after mannitol infusion during partial nephrectomy. We stress the importance of excellent intravenous catheter access and constant visual monitoring of the intravenous catheter site during and after mannitol infusion as ways to prevent this complication. Prompt recognition of compartment syndrome with appropriate intervention can prevent long-term sequelae.

  10. Abdominal Compartment Syndrome Secondary to Chronic Constipation

    Directory of Open Access Journals (Sweden)

    Helene Flageole

    2011-01-01

    Full Text Available Abdominal compartment syndrome (ACS is defined as an elevated intraabdominal pressure with evidence of organ dysfunction. The majority of published reports of ACS are in neonates with abdominal wall defects and in adults following trauma or burns, but it is poorly described in children. We describe the unusual presentation of an 11-year-old boy with a long history of chronic constipation who developed acute ACS requiring resuscitative measures and emergent disimpaction. He presented with a 2-week history of increasing abdominal pain, nausea, diminished appetite and longstanding encopresis. On exam, he was emaciated with a massively distended abdomen with a palpable fecaloma. Abdominal XR confirmed these findings. Within 24 hours of presentation, he became tachycardic and oliguric with orthostatic hypotension. Following two enemas, he acutely deteriorated with severe hypotension, marked tachycardia, acute respiratory distress, and a declining mental status. Endotracheal intubation, fluid boluses, and vasopressors were commenced, followed by emergent surgical fecal disimpaction. This resulted in rapid improvement in vital signs. He has been thoroughly investigated and no other condition apart from functional constipation has been identified. Although ACS secondary to constipation is extremely unusual, this case illustrates the need to actively treat constipation and what can happen if it is not.

  11. High resolution three-dimensional cardiac perfusion imaging using compartment-based k-t principal component analysis

    DEFF Research Database (Denmark)

    Vitanis, Viton; Manka, Robert; Giese, Daniel

    2011-01-01

    Three-dimensional myocardial perfusion imaging requires significant acceleration of data acquisition to achieve whole-heart coverage with adequate spatial and temporal resolution. The present article introduces a compartment-based k-t principal component analysis reconstruction approach, which...... permits three-dimensional perfusion imaging at 10-fold nominal acceleration. Using numerical simulations, it is shown that the compartment-based method results in accurate representations of dynamic signal intensity changes with significant improvements of temporal fidelity in comparison to conventional k...... component analysis for highly accelerated three-dimensional perfusion imaging....

  12. A functional dissection of PTEN N-terminus: implications in PTEN subcellular targeting and tumor suppressor activity.

    Science.gov (United States)

    Gil, Anabel; Rodríguez-Escudero, Isabel; Stumpf, Miriam; Molina, María; Cid, Víctor J; Pulido, Rafael

    2015-01-01

    Spatial regulation of the tumor suppressor PTEN is exerted through alternative plasma membrane, cytoplasmic, and nuclear subcellular locations. The N-terminal region of PTEN is important for the control of PTEN subcellular localization and function. It contains both an active nuclear localization signal (NLS) and an overlapping PIP2-binding motif (PBM) involved in plasma membrane targeting. We report a comprehensive mutational and functional analysis of the PTEN N-terminus, including a panel of tumor-related mutations at this region. Nuclear/cytoplasmic partitioning in mammalian cells and PIP3 phosphatase assays in reconstituted S. cerevisiae defined categories of PTEN N-terminal mutations with distinct PIP3 phosphatase and nuclear accumulation properties. Noticeably, most tumor-related mutations that lost PIP3 phosphatase activity also displayed impaired nuclear localization. Cell proliferation and soft-agar colony formation analysis in mammalian cells of mutations with distinctive nuclear accumulation and catalytic activity patterns suggested a contribution of both properties to PTEN tumor suppressor activity. Our functional dissection of the PTEN N-terminus provides the basis for a systematic analysis of tumor-related and experimentally engineered PTEN mutations.

  13. Characterization of MYG1 gene and protein: subcellular distribution and function

    DEFF Research Database (Denmark)

    Philips, Mari-Anne; Vikeså, Jonas; Luuk, Hendrik

    2009-01-01

    nuclear localization signal in the region between amino acids 33-39 and localizes to these compartments. No active shuttling of MYG1 between the nucleus and the mitochondria was detected and the distribution of MYG1 was not dependent on the phase of the cell cycle. Immunoprecipitation of C-terminally FLAG......-tagged MYG1 from HeLa cells did not identify any co-precipitated proteins. siRNA (short interfering RNA)-mediated knockdown of MYG1 mRNA was mainly followed by changes in the level of transcripts encoding factors involved in developmental tissue patterning and growth as well as immune-related processes....... CONCLUSIONS: Taken together, we infer that MYG1 is a ubiquitous nucleo-mitochondrial protein, with differential pattern and level of expression during embryonic development. MYG1 expression in normal adult tissues is stable and our data suggest MYG1 involvement in early developmental processes and also...

  14. Functional outcome of tibial fracture with acute compartment syndrome and correlation to deep posterior compartment pressure

    Science.gov (United States)

    Goyal, Saumitra; Naik, Monappa A; Tripathy, Sujit Kumar; Rao, Sharath K

    2017-01-01

    AIM To measure single baseline deep posterior compartment pressure in tibial fracture complicated by acute compartment syndrome (ACS) and to correlate it with functional outcome. METHODS Thirty-two tibial fractures with ACS were evaluated clinically and the deep posterior compartment pressure was measured. Urgent fasciotomy was needed in 30 patients. Definite surgical fixation was performed either primarily or once fasciotomy wound was healthy. The patients were followed up at 3 mo, 6 mo and one year. At one year, the functional outcome [lower extremity functional scale (LEFS)] and complications were assessed. RESULTS Three limbs were amputated. In remaining 29 patients, the average times for clinical and radiological union were 25.2 ± 10.9 wk (10 to 54 wk) and 23.8 ± 9.2 wk (12 to 52 wk) respectively. Nine patients had delayed union and 2 had nonunion who needed bone grafting to augment healing. Most common complaint at follow up was ankle stiffness (76%) that caused difficulty in walking, running and squatting. Of 21 patients who had paralysis at diagnosis, 13 (62%) did not recover and additional five patients developed paralysis at follow-up. On LEFS evaluation, there were 14 patients (48.3%) with severe disability, 10 patients (34.5%) with moderate disability and 5 patients (17.2%) with minimal disability. The mean pressures in patients with minimal disability, moderate disability and severe disability were 37.8, 48.4 and 58.79 mmHg respectively (P < 0.001). CONCLUSION ACS in tibial fractures causes severe functional disability in majority of patients. These patients are prone for delayed union and nonunion; however, long term disability is mainly because of severe soft tissue contracture. Intra-compartmental pressure (ICP) correlates with functional disability; patients with relatively high ICP are prone for poor functional outcome. PMID:28567342

  15. Trace elements distribution in environmental compartments

    Energy Technology Data Exchange (ETDEWEB)

    Queiroz, Juliana C. de; Peres, Sueli da Silva; Godoy, Maria Luiza D.P., E-mail: suelip@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2017-11-01

    Trace elements term defines the presence of low concentrations metals at environment. Some of them are considered biologically essential, as Co, Cu and Mn. Others can cause detriment to environment and human health, as Pb, Cd, Hg, As, Ti and U. A large number of them have radioactive isotopes, implying the evaluation of risks for human health should be done considering the precepts of environmental radiological protection. The ecosystem pollution with trace elements generates changes at the geochemistry cycle of these elements and in environmental quality. Soils have single characteristics when compared with another components of biosphere (air, water and biota), cause they introduce themselves not only as a drain towards contaminants, but also as natural buffer that control the transport of chemical elements and other substances for atmosphere, hydrosphere and biota. The main purpose of environmental monitoring program is to evaluate the levels of contaminants in the various compartments of the environment: natural or anthropogenic, and to assess the contribution of a potential contaminant source on the environment. Elemental Composition for the collected samples was determined by inductively coupled plasma mass spectroscopy. The main objective of this work was to evaluate the map baseline of concentration of interest trace elements in environmental samples of water, sediment and soil from Environmental Monitoring Program of Instituto de Radioprotecao e Dosimetria (IRD). The samples were analyzed using an inductively coupled plasma mass spectrometer (ICP-MS) at IRD. >From the knowledge of trace elements concentrations, could be evaluated the environmental quality parameters at the studied ecosystems. The data allowed evaluating some relevant aspects of the study of trace elements in soil and aquatic systems, with emphasis at the distribution, concentration and identification of main anthropic sources of contamination at environment. (author)

  16. Differential subcellular targeting of glutamate receptor subtypes during homeostatic synaptic plasticity.

    Science.gov (United States)

    Soares, Cary; Lee, Kevin F H; Nassrallah, Wissam; Béïque, Jean-Claude

    2013-08-14

    Homeostatic processes are believed to contribute to the stability of neuronal networks that are perpetually influenced by Hebbian forms of synaptic plasticity. Whereas the rules governing the targeting and trafficking of AMPA and NMDA subtypes of glutamate receptors during rapid Hebbian LTP have been extensively studied, those that are operant during homeostatic forms of synaptic strengthening are less well understood. Here, we used biochemical, biophysical, and pharmacological approaches to investigate glutamate receptor regulation during homeostatic synaptic plasticity. We show in rat organotypic hippocampal slices that prolonged network silencing induced a robust surface upregulation of GluA2-lacking AMPARs, not only at synapses, but also at extrasynaptic dendritic and somatic regions of CA1 pyramidal neurons. We also detected a shift in NMDAR subunit composition that, in contrast to the cell-wide surface delivery of GluA2-lacking AMPARs, occurred exclusively at synapses. The subunit composition and subcellular distribution of AMPARs and NMDARs are therefore distinctly regulated during homeostatic synaptic plasticity. Thus, because subunit composition dictates key channel properties, such as agonist affinity, gating kinetics, and calcium permeability, the homeostatic synaptic process transcends the simple modulation of synaptic strength by also regulating the signaling and integrative properties of central synapses.

  17. Diversity in subcellular targeting of the PP2A B'eta subfamily members.

    Science.gov (United States)

    Matre, Polina; Meyer, Christian; Lillo, Cathrine

    2009-10-01

    Protein phosphatase 2A (PP2A) is a serine/threonine-specific phosphatase comprising a catalytic subunit (C), a scaffolding subunit (A), and a regulatory subunit (B). The B subunits are believed to be responsible for substrate specificity and localization of the PP2A complex. In plants, three families of B subunits exist, i.e. B (B55), B', and B''. Here, we report differential subcellular targeting within the Arabidopsis B'eta subfamily, which consists of the close homologs B'eta, B'theta, B'gamma and B'zeta. Phenotypes of corresponding knockouts were observed, and particularly revealed delayed flowering for the B'eta knockout. The B' subunits were linked to fluorescent tags and transiently expressed in various tissues of onion, tobacco and Arabidopsis. B'eta and B'gamma targeted the cytosol and nucleus. B'zeta localized to the cytoplasm and partly co-localized with mitochondrial markers when the N-terminus was free. Provided its C-terminus was free, the B'theta subunit targeted peroxisomes. The importance of the C-terminal end for peroxisomal targeting was further confirmed by truncation of the C-terminus. The results revealed that the closely related B' subunits are targeting different organelles in plants, and exemplify the usage of the peptide serine-serine-leucine as a PTS1 peroxisomal signaling peptide.

  18. Subcellular distribution of glutathione and its dynamic changes under oxidative stress in the yeast Saccharomyces cerevisiae

    Science.gov (United States)

    Zechmann, Bernd; Liou, Liang-Chun; Koffler, Barbara E; Horvat, Lucija; Tomašić, Ana; Fulgosi, Hrvoje; Zhang, Zhaojie

    2011-01-01

    Glutathione is an important antioxidant in most prokaryotes and eukaryotes. It detoxifies reactive oxygen species and is also involved in the modulation of gene expression, in redox signaling, and in the regulation of enzymatic activities. In this study, the subcellular distribution of glutathione was studied in Saccharomyces cerevisiae by quantitative immunoelectron microscopy. Highest glutathione contents were detected in mitochondria and subsequently in the cytosol, nuclei, cell walls, and vacuoles. The induction of oxidative stress by hydrogen peroxide (H2O2) led to changes in glutathione-specific labeling. Three cell types were identified. Cell types I and II contained more glutathione than control cells. Cell type II differed from cell type I in showing a decrease in glutathione-specific labeling solely in mitochondria. Cell type III contained much less glutathione contents than the control and showed the strongest decrease in mitochondria, suggesting that high and stable levels of glutathione in mitochondria are important for the protection and survival of the cells during oxidative stress. Additionally, large amounts of glutathione were relocated and stored in vacuoles in cell type III, suggesting the importance of the sequestration of glutathione in vacuoles under oxidative stress. PMID:22093747

  19. Compartment syndrome causes systemic inflammation in a rat.

    Science.gov (United States)

    Lawendy, A-R; Bihari, A; Sanders, D W; Badhwar, A; Cepinskas, G

    2016-08-01

    Compartment syndrome results from increased intra-compartmental pressure (ICP) causing local tissue ischaemia and cell death, but the systemic effects are not well described. We hypothesised that compartment syndrome would have a profound effect not only on the affected limb, but also on remote organs. Using a rat model of compartment syndrome, its systemic effects on the viability of hepatocytes and on inflammation and circulation were directly visualised using intravital video microscopy. We found that hepatocellular injury was significantly higher in the compartment syndrome group (192 PI-labelled cells/10(-1) mm(3), standard error of the mean (sem) 51) compared with controls (30 PI-labelled cells/10(-1) mm(3), sem 12, p compartment syndrome group (5 leukocytes/30s/10 000 μm(2), sem 1) than controls (0.2 leukocytes/30 s/10 000 μm(2), sem 0.2, p Compartment syndrome can be accompanied by severe systemic inflammation and end organ damage. This study provides evidence of the relationship between compartment syndrome in a limb and systemic inflammation and dysfunction in a remote organ. Cite this article: Bone Joint J 2016; 98-B:1132-7. ©2016 The British Editorial Society of Bone & Joint Surgery.

  20. Robust classification of subcellular location patterns in high resolution 3D fluorescence microscope images.

    Science.gov (United States)

    Chen, Xiang; Murphy, Robert

    2004-01-01

    Knowledge of a protein's subcellular location is essential to a complete understanding of its functions. Automated interpretation methods for protein location patterns are needed for proteomics projects, and we have previously described systems for classifying the major subcellular patterns in cultured mammalian cells. We describe here the calculation of improved 3D Haralick texture features, which yielded a near-perfect classification accuracy when combined with 3D morphological and edge features. In particular, a set of 7 features achieved 98% overall accuracy for classifying 10 major subcellular location patterns in HeLa cells.

  1. Stochastic Turing Patterns: Analysis of Compartment-Based Approaches

    KAUST Repository

    Cao, Yang

    2014-11-25

    © 2014, Society for Mathematical Biology. Turing patterns can be observed in reaction-diffusion systems where chemical species have different diffusion constants. In recent years, several studies investigated the effects of noise on Turing patterns and showed that the parameter regimes, for which stochastic Turing patterns are observed, can be larger than the parameter regimes predicted by deterministic models, which are written in terms of partial differential equations (PDEs) for species concentrations. A common stochastic reaction-diffusion approach is written in terms of compartment-based (lattice-based) models, where the domain of interest is divided into artificial compartments and the number of molecules in each compartment is simulated. In this paper, the dependence of stochastic Turing patterns on the compartment size is investigated. It has previously been shown (for relatively simpler systems) that a modeler should not choose compartment sizes which are too small or too large, and that the optimal compartment size depends on the diffusion constant. Taking these results into account, we propose and study a compartment-based model of Turing patterns where each chemical species is described using a different set of compartments. It is shown that the parameter regions where spatial patterns form are different from the regions obtained by classical deterministic PDE-based models, but they are also different from the results obtained for the stochastic reaction-diffusion models which use a single set of compartments for all chemical species. In particular, it is argued that some previously reported results on the effect of noise on Turing patterns in biological systems need to be reinterpreted.

  2. Treatment of Atypical Compartment Syndrome Due to Proteus Infection.

    Science.gov (United States)

    Stull, Justin; Bhat, Suneel; Miller, Andrew J; Hoffman, Ryan; Wang, Mark L

    2017-01-01

    Compartment syndrome is an orthopedic emergency with a multitude of etiologies. Although it is most commonly associated with trauma to the extremity, hematoma and infection are 2 rare etiologies of insidious compartment syndrome. Proteus mirabilis is an opportunistic gram-negative species that can infect the respiratory tract, urinary tract, and open wounds. The authors present the case of a 69-year-old woman who developed tissue necrosis and compartment syndrome secondary to an untreated hematoma infected by P mirabilis. This case involves an atypical presentation caused by an untreated infected hematoma, emphasizing the need for a high index of suspicion. Current literature supports immediate surgical intervention in the clinical scenario of fulminant compartment syndrome, regardless of compartment pressure findings. The probability of compartment syndrome in the patient presenting with pain, paresthesias, paresis, and pain with passive stretch, all of which were positive findings in this patient, has been reported to be 98%. Thus, Doppler evaluation and intercompartmental pressures were considered but forgone to expedite operative treatment. Emergent 4-compartment fasciotomies, with excision and debridement of nonviable tissue, are potentially limb-saving procedures, intended to limit loss of function and obviate the need for lower extremity amputation. The decision was made to perform a dual-incision fasciotomy to avoid contamination of the uninvolved compartments with a standard single-incision approach. To date, this represents the first report in the English literature of the insidious onset of tissue necrosis secondary to a Proteus-infected hematoma, highlighting a unique etiology of atypical compartment syndrome. [Orthopedics. 2017; 40(1):e176-e178.]. Copyright 2016, SLACK Incorporated.

  3. Silent compartment syndrome in children: a report of five cases.

    Science.gov (United States)

    Lee, Christopher; Lightdale-Miric, Nina; Chang, Emory; Kay, Robert

    2014-09-01

    Compartment syndrome does not always present classically in the pediatric population, making clinical diagnosis uniquely challenging. The purpose of this study was to identify signs and symptoms of compartment syndrome that may help risk-stratify pediatric patients upon presentation, as well as to report outcomes of 'silent' compartment syndrome in children. A retrospective review of cases of 'silent' compartment syndrome at a level I pediatric trauma center between 2000 and 2010 was conducted. Patient demographics and clinical data were reviewed, including complications and patient outcomes. Radiographs taken at presentation, on intraoperative fluoroscopy, and at postoperative follow-up were reviewed for fracture type, and severity and outcome analyses. Five patients were found to have compartment syndrome without the presence of significant pain at rest or on passive range of motion. The study included three male and two female patients with a median age of 7 years. Three upper-extremity and two lower-extremity fractures were involved. The mean time from presentation to surgery was 14 h. At presentation, three of five patients had muscle paralysis, whereas at diagnosis of compartment syndrome, four of five had paralysis. Of the classic five P's, a maximum of two were found at diagnosis. The mean clinical follow-up period was 11 months (2-26 months). Long-term complications from compartment syndrome were found in one of five patients, who at the most recent follow-up, continued to be debilitated. This study reviews a series of cases of 'silent' compartment syndrome and confirms its atypical presentation. It is recommended that caution be used when assessing fractures with high risk for compartment syndrome in children, especially those complicated by nerve injury, as they do not always present in the classic manner, with missed diagnosis leading to significant functional deficits. IV.

  4. Redirecting the Cyanobacterial Bicarbonate Transporters BicA and SbtA to the Chloroplast Envelope: Soluble and Membrane Cargos Need Different Chloroplast Targeting Signals in Plants.

    Directory of Open Access Journals (Sweden)

    Vivien eRolland

    2016-02-01

    Full Text Available Most major crops used for human consumption are C3 plants, which yields are limited by photosynthetic inefficiency. To circumvent this, it has been proposed to implement the cyanobacterial CO2-concentrating mechanism (CCM, principally consisting of bicarbonate transporters and carboxysomes, into plant chloroplasts. As it is currently not possible to recover homoplasmic transplastomic monocots, foreign genes must be introduced in these plants via nuclear transformation. Consequently, it is paramount to ensure that resulting proteins reach the appropriate sub-cellular compartment, which for cyanobacterial transporters BicA and SbtA, is the chloroplast inner-envelope membrane (IEM. At present, targeting signals to redirect large transmembrane proteins from non-chloroplastic organisms to plant chloroplast envelopes are unknown. The goal of this study was to identify such signals, using agrobacteria-mediated transient expression and confocal microscopy to determine the sub-cellular localization of ~37 GFP-tagged chimeras. Initially, fragments of chloroplast proteins known to target soluble cargos to the stroma were tested for their ability to redirect BicA, but they proved ineffective. Next, different N-terminal regions from Arabidopsis IEM transporters were tested. We demonstrated that the N-terminus of AtHP59, AtPLGG1 or AtNTT1 (92-115 amino acids, containing a cleavable chloroplast transit peptide (cTP and a membrane protein leader (MPL, was sufficient to redirect BicA or SbtA to the chloroplast envelope. This constitutes the first evidence that nuclear-encoded transmembrane proteins from non-chloroplastic organisms can be targeted to the envelope of plant chloroplasts; a finding which represents an important advance in chloroplast engineering by opening up the door to further manipulation of the chloroplastic envelope.

  5. Current thinking about acute compartment syndrome of the lower extremity

    Science.gov (United States)

    Shadgan, Babak; Menon, Matthew; Sanders, David; Berry, Gregg; Martin, Claude; Duffy, Paul; Stephen, David; O’Brien, Peter J.

    2010-01-01

    Acute compartment syndrome of the lower extremity is a clinical condition that, although uncommon, is seen fairly regularly in modern orthopedic practice. The pathophysiology of the disorder has been extensively described and is well known to physicians who care for patients with musculoskeletal injuries. The diagnosis, however, is often difficult to make. In this article, we review the clinical risk factors of acute compartment syndrome of the lower extremity, identify the current concepts of diagnosis and discuss appropriate treatment plans. We also describe the Canadian medicolegal environment in regard to compartment syndrome of the lower extremity. PMID:20858378

  6. Acute Idiopathic Compartment Syndrome of the Forearm in an Adolescent

    Directory of Open Access Journals (Sweden)

    Smith, Kelley

    2014-11-01

    Full Text Available Acute compartment syndrome (ACS is a condition typically associated with long bone fractures or severe trauma; however, non-traumatic etiologies also occur. We describe a case of an otherwise healthy female pediatric patient presenting with unilateral forearm pain without an inciting injury. Intracompartmental pressures of the forearm were measured and she was diagnosed with idiopathic compartment syndrome. Our goal is to encourage clinicians to consider acute compartment syndrome even in the absence of trauma. [West J Emerg Med. 2015;16(1:158-160.

  7. Endosomal pH in Neuronal Signaling and Synaptic Transmission: Role of Na+/H+ Exchangers

    Directory of Open Access Journals (Sweden)

    Graham H Diering

    2014-01-01

    Full Text Available Neuronal precursor cells extend multiple neurites during development, one of which extends to form an axon whereas others develop into dendrites. Chemical stimulation of N-methyl D-aspartate (NMDA receptor in fully-differentiated neurons induces projection of dendritic spines, small spikes protruding from dendrites, thereby establishing another layer of polarity within the dendrite. Neuron-enriched Na+/H+ exchanger NHE5 contributes to both neurite growth and dendritic spine formation. In resting neurons and neuro-endocrine cells, neuron-enriched NHE5 is predominantly associated with recycling endosomes where it colocalizes with nerve growth factor (NGF receptor TrkA. NHE5 potently acidifies the lumen of TrkA-positive recycling endosomes and regulates cell-surface targeting of TrkA, whereas chemical stimulation of NMDA receptor rapidly recruits NHE5 to dendritic spines, alkalinizes dendrites and down-regulates the dendritic spine formation. Possible roles of NHE5 in neuronal signaling via proton movement in subcellular compartments are discussed.

  8. The impact of discrete compartments of a multi-compartment collagen-GAG scaffold on overall construct biophysical properties.

    Science.gov (United States)

    Weisgerber, D W; Kelkhoff, D O; Caliari, S R; Harley, B A C

    2013-12-01

    Orthopedic interfaces such as the tendon-bone junction (TBJ) present unique challenges for biomaterials development. Here we describe a multi-compartment collagen-GAG scaffold fabricated via lyophilization that contains discrete mineralized (CGCaP) and non-mineralized (CG) regions joined by a continuous interface. Modifying CGCaP preparation approaches, we demonstrated scaffold variants of increasing mineral content (40 vs. 80wt% CaP). We report the impact of fabrication parameters on microstructure, composition, elastic modulus, and permeability of the entire multi-compartment scaffold as well as discrete mineralized and non-mineralized compartments. Notably, individual mineralized and non-mineralized compartments differentially impacted the global properties of the multi-compartment composite. Of particular interest for the development of mechanically-loaded multi-compartment composites, the elastic modulus and permeability of the entire construct were governed primarily by the non-mineralized and mineralized compartments, respectively. Based on these results we hypothesize spatial variations in scaffold structural, compositional, and mechanical properties may be an important design parameter in orthopedic interface repair. © 2013 Elsevier Ltd. All rights reserved.

  9. Intracellular delivery of nanocarriers and targeting to subcellular organelles.

    Science.gov (United States)

    Jhaveri, Aditi; Torchilin, Vladimir

    2016-01-01

    Recent trends in drug delivery indicate a steady increase in the use of targeted therapeutics to enhance the specific delivery of biologically active payloads to diseased tissues while avoiding their off-target effects. However, in most cases, the distribution of therapeutics inside cells and their targeting to intracellular targets still presents a formidable challenge. The main barrier to intracellular delivery is the translocation of therapeutic molecules across the cell membrane, and ultimately through the membrane of their intracellular target organelles. Another prerequisite for an efficient intracellular localization of active molecules is their escape from the endocytic pathway. Pharmaceutical nanocarriers have demonstrated substantial advantages for the delivery of therapeutics and offer elegant platforms for intracellular delivery. They can be engineered with both intracellular and organelle-specific targeting moieties to deliver encapsulated or conjugated cargoes to specific sub-cellular targets. In this review, we discuss important aspects of intracellular drug targeting and delivery with a focus on nanocarriers modified with various ligands to specifically target intracellular organelles. Intracellular delivery affords selective localization of molecules to their target site, thus maximizing their efficacy and safety. The advent of novel nanocarriers and targeting ligands as well as exploration of alternate routes for the intracellular delivery and targeting has prompted extensive research, and promises an exciting future for this field.

  10. How prenylation and S-acylation regulate subcellular targeting and function of ROP GTPases.

    Science.gov (United States)

    Sorek, Nadav; Henis, Yoav I; Yalovsky, Shaul

    2011-07-01

    Rho of Plants (ROP) small G proteins function at discrete domains of the plasma and possibly endo membranes. ROPs are synthesized as soluble proteins and their attachment to membranes and partitioning in membrane microdomains are facilitated by the posttranslational lipid modifications prenylation and/or S-acylation. Based on their amino acid sequences, ROPs can be classified into two major subgroups: type-I ROPs terminate with a canonical CaaX box motif and are prenylated primarily by geranylgeranyltransferase-I (GGT-I) and to a lesser extent by farnesyltransferase (FT). Type-II ROPs terminate with a plant specific GC-CG box domain and are attached to the plasma membrane by stable S-acylation. In addition, type-I and possibly also type-II ROPs undergo activation dependent transient S-acylation in the G-domain and consequent partitioning into lipid rafts. Surprisingly, although geranylgeranylation is required for the membrane attachment of type-I ROPs and the γ subunits of heterotrimeric G proteins, Arabidopsis mutants lacking GGT-I function have a mild phenotype compared to wild type plants. The mild phenotype of the ggt-I mutants suggested that farnesylation by FT may compensate for the loss of GGT-I function and that possibly the prenylated type-I and S-acylated type-II ROPS have some overlapping functions. In a paper recently published in Plant Physiology we examined the role of the prenyl group type in type-I ROP function and membrane interaction dynamics and the functional redundancy between type-I and type-II ROPs. This study complements a second paper in which we examined the role of G-domain transient S-acylation in the membrane interaction dynamics and signaling by type-I ROPs. Together these two studies provide a framework for realizing the role of prenylation and S-acylation in subcellular targeting, membrane interaction dynamics and signaling by ROP GTPases.

  11. Predicting the subcellular localization of viral proteins within a mammalian host cell

    Directory of Open Access Journals (Sweden)

    Thomas DY

    2006-04-01

    Full Text Available Abstract Background The bioinformatic prediction of protein subcellular localization has been extensively studied for prokaryotic and eukaryotic organisms. However, this is not the case for viruses whose proteins are often involved in extensive interactions at various subcellular localizations with host proteins. Results Here, we investigate the extent of utilization of human cellular localization mechanisms by viral proteins and we demonstrate that appropriate eukaryotic subcellular localization predictors can be used to predict viral protein localization within the host cell. Conclusion Such predictions provide a method to rapidly annotate viral proteomes with subcellular localization information. They are likely to have widespread applications both in the study of the functions of viral proteins in the host cell and in the design of antiviral drugs.

  12. Compartment Syndrome of the Gluteus Medius Occurred without Bleeding or Trauma: A Case Report

    OpenAIRE

    Kong, Gyu-Min; Kwon, Yong-Uk; Park, Jun-Ho

    2015-01-01

    Compartment syndrome is an ischemic change resulting from an increase in compartment pressure. Initially, patients present with direct tenderness and swelling, and the weak circulation secondary to compartment syndrome can eventually lead to motor and sensory impairment. If the increase in pressure results in neurological impairment, emergency intervention is required to decompress the compartment. Typically, compartment syndrome develops on forearms or lower legs. The gluteal compartment is ...

  13. Elimination behavior of shelter dogs housed in double compartment kennels

    National Research Council Canada - National Science Library

    Wagner, Denae; Newbury, Sandra; Kass, Philip; Hurley, Kate

    2014-01-01

    ... being. Dogs in animal shelters are often housed in one of two types of confinement housing - single kennels and rooms or double compartment kennels and rooms most often separated by a guillotine door...

  14. The Pathophysiology, Diagnosis and Current Management of Acute Compartment Syndrome

    Science.gov (United States)

    Donaldson, James; Haddad, Behrooz; Khan, Wasim S

    2014-01-01

    Acute compartment syndrome (ACS) is a surgical emergency warranting prompt evaluation and treatment. It can occur with any elevation in interstitial pressure in a closed osseo-fascial compartment. Resultant ischaemic damage may be irreversible within six hours and can result in long-term morbidity and even death. The diagnosis is largely clinical with the classical description of ‘pain out of proportion to the injury’. Compartment pressure monitors can be a helpful adjunct where the diagnosis is in doubt. Initial treatment is with the removal of any constricting dressings or casts, avoiding hypotension and optimizing tissue perfusion by keeping the limb at heart level. If symptoms persist, definitive treatment is necessary with timely surgical decompression of all the involved compartments. This article reviews the pathophysiology, diagnosis and current management of ACS. PMID:25067973

  15. A Case of Acute Atraumatic Compartment Syndrome of the Thigh.

    Science.gov (United States)

    Gutfraynd, Alexander; Philpott, Sheila

    2016-09-01

    In the absence of trauma, compartment syndrome of the thigh is rare. Several case reports have described compartment syndrome in the presence of trauma, comorbid medical conditions, and acute muscle overuse. Very few reports have demonstrated an acute onset of atraumatic thigh compartment syndrome. A 24-year-old man presented to the Emergency Department (ED) with a painful and swollen left thigh immediately after a night of dancing at a concert. He was found to have an elevated intracompartmental quadriceps pressure of 45 mm Hg in the ED, which led to his transfer to the operating room for an emergent fasciotomy. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Although acute, atraumatic compartment syndrome of the thigh is a rare entity, failure to diagnose it promptly can lead to muscle necrosis, permanent neurologic deficits, and amputation. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Fulminant crural compartment syndrome preceded by psychogenic polydipsia

    DEFF Research Database (Denmark)

    Ulstrup, Anton; Ugleholdt, Randi; Rasmussen, Jeppe Vejlgaard

    2015-01-01

    We report a case of bilateral anterolateral crural compartment syndrome elicited by hyponatraemia and psychogenic polydipsia. The unusual constellation of clinical findings and diminished pain expression made initial diagnostic procedures challenging. The possible pathogenesis and treatment options...

  17. Canthal cutdown for emergent treatment of orbital compartment syndrome.

    Science.gov (United States)

    Strand, Andrew T; Czyz, Craig N; Gibson, Amanda

    2017-10-01

    This article evaluates the use of a "canthal cutdown" technique in orbital compartment syndrome in a cadaveric model. Twelve cadaver orbits were used to simulate orbital compartment syndrome using a blood analog solution. Two pressure probes, in different orbital locations, were used to monitor orbital pressure. Pressure was monitored during successive procedures: canthotomy, cantholysis, and canthal cutdown. Orbits were then re-injected with solution, simulating an active orbital hemorrhage, and pressure measurements were recorded over a 10-minute duration. No statistically significant difference was found between the two orbital pressure monitoring devices at each measurement point (p = 0.99). Significant pressure reductions, for both probes, were observed after canthal cutdown compared to initial measurement after injection of 20 mL blood analog (p compartment syndrome and temporizing treatment of compartment syndrome from active orbital hemorrhages.

  18. Propofol extravasation: a rare cause of compartment syndrome

    Science.gov (United States)

    Kalraiya, Ashish Jain; Madanipour, Suroosh; Colaco, Henry; Cobiella, Carlos

    2015-01-01

    We detail a rare cause of forearm compartment syndrome that occurred in an 18-year-old patient who presented with a Glasgow Coma Scale of 13/15 after a mixed drug overdose and subsequently required intubation. She suffered extravasation of her propofol infusion, which resulted in intrinsic compression within her forearm muscle compartments. Fortunately, the diagnosis of compartment syndrome was made swiftly and the patient was taken to theatre within 3 h where she underwent an emergency forearm fasciotomy. She made an uneventful recovery and at follow-up her wounds had healed well with no associated morbidity or loss of function. The learning points of this study highlight the importance of thoroughly understanding the signs and symptoms of compartment syndrome while maintaining a high index of suspicion. In addition to a thorough history and examination, consideration of the potential underlying causes allows for a swifter diagnosis and a quicker transition to theatre. PMID:25953583

  19. Fire safety arrangement of inhabited pressurized compartments of manned spacecraft

    Science.gov (United States)

    Bolodian, Ivan; Melikhov, Anatoliy; Tanklevskiy, Leonid

    2017-06-01

    The article deals with innovative technical solutions that provide fire safety in inhabited pressurized compartments of manned spacecraft by means of a fireproof device of inhabited pressurized compartments via application of engineering means of fire prevention and fire spreading prevention by lowering fire load in an inhabited pressurized module up to the point when the maximum possible levels of fire factors in an inhabited pressurized compartment of a manned spacecraft are prevented. Represented technical solutions are used at the present time according to stated recommendations during provision of fire safety of equipment created by a number of Russian organizations for equipage of inhabited pressurized compartments of spacecraft of the Russian segment of International space station.

  20. Elimination behavior of shelter dogs housed in double compartment kennels

    National Research Council Canada - National Science Library

    Wagner, Denae; Newbury, Sandra; Kass, Philip; Hurley, Kate

    2014-01-01

    .... Dogs in animal shelters are often housed in one of two types of confinement housing - single kennels and rooms or double compartment kennels and rooms most often separated by a guillotine door...

  1. Turbofan Engine Core Compartment Vent Aerodynamic Configuration Development Methodology

    Science.gov (United States)

    Hebert, Leonard J.

    2006-01-01

    This paper presents an overview of the design methodology used in the development of the aerodynamic configuration of the nacelle core compartment vent for a typical Boeing commercial airplane together with design challenges for future design efforts. Core compartment vents exhaust engine subsystem flows from the space contained between the engine case and the nacelle of an airplane propulsion system. These subsystem flows typically consist of precooler, oil cooler, turbine case cooling, compartment cooling and nacelle leakage air. The design of core compartment vents is challenging due to stringent design requirements, mass flow sensitivity of the system to small changes in vent exit pressure ratio, and the need to maximize overall exhaust system performance at cruise conditions.

  2. Absorbed dose at subcellular level by Monte Carlo simulation for a {sup 99m}Tc-peptide with nuclear internalization

    Energy Technology Data Exchange (ETDEWEB)

    Rojas C, E. L.; Ferro F, G. [ININ, Carretera Mexico-Toluca s/n, Ocoyoacac 52750, Estado de Mexico (Mexico); Santos C, C. L., E-mail: leticia.rojas@inin.gob.m [Universidad Autonoma del Estado de Mexico, Paseo Tollocan esquina Paseo Colon s/n, Toluca 50120, Estado de Mexico (Mexico)

    2010-10-15

    The utility of radiolabeled peptides for the early and specific diagnosis of cancer is being investigated around the world. Recent investigations have demonstrated the specificity of {sup 99m}Tc-bombesin conjugates to target breast and prostate cancer cells. The novel idea of adding the Tat (49-57) peptide to the radiopharmaceutical in order to penetrate the cell nucleus is a new proposal for therapy at cellular level. {sup 99m}Tc radionuclide produces Auger energy of 0.9 keV/decay and internal conversion electron energy of 15.4 keV/decay, which represent 11.4% of the total {sup 99m}Tc energy released per decay. It is expected that the dose delivered at specific microscopic levels in cancer cells induce a therapeutic effect. The aim of this research was to assess in vitro internalization kinetics in breast and prostate cancer cells of {sup 99m}Tc-Tat(49-57)-bombesin and to evaluate the radiation absorbed dose at subcellular level simulating the electron transport. The pen main program from the 2006 version of the Penelope code was used to simulate and calculate the absorbed dose by Auger and internal conversion electron contribution in the membrane, cytoplasm and nucleus of Pc-3 prostate cancer and MCF7 and MDA human breast cancer cell lines. Nuclear data were obtained from the 2002 BNM-LNHB {sup 99m}Tc decay scheme. The spatial distribution of the absorbed doses to the membrane, cytoplasm and nucleus were calculated using a geometric model built from real images of cancer cells. The elemental cell composition was taken from the literature. The biokinetic data were obtained evaluating total disintegrations in each subcellular compartment by integration of the time-activity curves acquired from experimental data. Results showed that 61, 63 and 46% of total disintegrations per cell-bound {sup 99m}Tc-Tat-Bn activity unit occurred in the nucleus of Pc-3, MCF7 and MDA-MB231 respectively. {sup 99m}Tc--Tat-Bn absorbed doses were 1.78, 5.76 and 2.59 Gy/Bq in the nucleus of

  3. Acute pediatric leg compartment syndrome in chronic myeloid leukemia.

    Science.gov (United States)

    Cohen, Eric; Truntzer, Jeremy; Trunzter, Jeremy; Klinge, Steve; Schwartz, Kevin; Schiller, Jonathan

    2014-11-01

    Acute compartment syndrome is an orthopedic surgical emergency and may result in devastating complications in the setting of delayed or missed diagnosis. Compartment syndrome has a variety of causes, including posttraumatic or postoperative swelling, external compression, burns, bleeding disorders, and ischemia-reperfusion injury. Rare cases of pediatric acute compartment syndrome in the setting of acute myeloid leukemia and, even less commonly, chronic myeloid leukemia have been reported. The authors report the first known case of pediatric acute compartment syndrome in a patient without a previously known diagnosis of chronic myeloid leukemia. On initial examination, an 11-year-old boy presented with a 2-week history of progressive left calf pain and swelling after playing soccer. Magnetic resonance imaging scan showed a hematoma in the left superficial posterior compartment. The patient had unrelenting pain, intermittent lateral foot parethesias, and inability to bear weight. Subsequently, he was diagnosed with acute compartment syndrome and underwent fasciotomy and evacuation of a hematoma. Laboratory results showed an abnormal white blood cell count of 440×10(9)/L (normal, 4.4-11×10(9)) and international normalized ratio of 1.3 (normal, 0.8-1.2). Further testing included the BCR-ABL1 fusion gene located on the Philadelphia chromosome, leading to a diagnosis of chronic myeloid leukemia. Monotherapy with imatinib mesylate (Gleevec) was initiated. This report adds another unique case to the growing literature on compartment syndrome in the pediatric population and reinforces the need to consider compartment syndrome, even in unlikely clinical scenarios. Copyright 2014, SLACK Incorporated.

  4. Hypothyroid-induced acute compartment syndrome in all extremities

    OpenAIRE

    Musielak, Matthew C.; Chae, Jung Hee

    2016-01-01

    Acute compartment syndrome (ACS) is an uncommon complication of uncontrolled hypothyroidism. If unrecognized, this can lead to ischemia, necrosis and potential limb loss. A 49-year-old female presented with the sudden onset of bilateral lower and upper extremity swelling and pain. The lower extremity anterior compartments were painful and tense. The extensor surface of the upper extremities exhibited swelling and pain. Motor function was intact, however, limited due to pain. Bilateral lower e...

  5. Accuracy of measurement of hand compartment pressures: a cadaveric study.

    Science.gov (United States)

    Wong, Justin C; Vosbikian, Michael M; Dwyer, Joseph M; Ilyas, Asif M

    2015-04-01

    To determine the accuracy of digital palpation for clinical assessment of elevated intracompartmental pressure compared with needle manometry in a simulated compartment syndrome of the hand. Three cadaveric hands were configured with interstitial fluid infusion and an arterial line pressure monitor to create and continuously measure intracompartmental pressure in the thenar and hypothenar compartments. Seventeen assessors clinically judged the presence or absence of compartment syndrome based on digital palpation for firmness and then measured pressures with a handheld manometer. An intracompartmental pressure threshold of 30 mm Hg or greater was used to diagnose compartment syndrome. The sensitivity and specificity of digital palpation of the thenar eminence were 49% and 79%, respectively, with a positive predictive value (PPV) of 86% and negative predictive value (NPV) of 37%. Using the handheld manometer, the sensitivity and specificity increased to 97% and 86% with a PPV of 95% and NPV of 92%. The sensitivity and specificity of digital palpation of the hypothenar eminence were 62% and 83%, respectively, with improvement of 100% and 100%, respectively, with a handheld manometer. For the hypothenar compartment, use of a handheld manometer improved the PPV from 92% to 100% and the NPV from 40% to 100% compared with digital palpation. Digital palpation alone was insufficient to detect elevated compartment pressures in hands at risk for compartment syndrome. Handheld invasive pressure measurement was a useful adjunct for detecting elevated interstitial tissue pressures and may aid in diagnosing compartment syndrome. Diagnostic II. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  6. Endoscopic Fascia Release for Forearm Chronic Exertional Compartment Syndrome: Case Report and Surgical Technique

    National Research Council Canada - National Science Library

    Miller, Elizabeth A; Cobb, Anna L; Cobb, Tyson K

    Background: Chronic exertional compartment syndrome (CECS) of the forearm is traditionally treated with open compartment release requiring large incisions that can result in less than optimal esthetic results...

  7. Compartment Syndrome of the Gluteus Medius Occurred without Bleeding or Trauma: A Case Report.

    Science.gov (United States)

    Kong, Gyu-Min; Kwon, Yong-Uk; Park, Jun-Ho

    2015-12-01

    Compartment syndrome is an ischemic change resulting from an increase in compartment pressure. Initially, patients present with direct tenderness and swelling, and the weak circulation secondary to compartment syndrome can eventually lead to motor and sensory impairment. If the increase in pressure results in neurological impairment, emergency intervention is required to decompress the compartment. Typically, compartment syndrome develops on forearms or lower legs. The gluteal compartment is rarely the location of compartment syndrome and only a few cases have been presented in the literature with trauma or hematoma. We have treated a patient with gluteal compartment syndrome who presented with no history of trauma or hemorrhage and present that case report here.

  8. Return to activity following fasciotomy for chronic exertional compartment syndrome.

    Science.gov (United States)

    Irion, Val; Magnussen, Robert A; Miller, Timothy L; Kaeding, Christopher C

    2014-10-01

    Diagnosis of chronic exertional compartment syndrome (CECS) is relatively rare but has been well documented in athletes. There are, however, few reports regarding return to athletic activity after surgery among elite-level athletes. We hypothesized that a majority of elite-level athletes would successfully return to their previous level of competition following fasciotomy for CECS. A retrospective chart review was performed to identify elite-level athletes (collegiate or professional sport participation) who underwent fasciotomy for CECS over a 3-year period. Data collected included sport or activity, treatment and surgical details, time away from sport/activity after surgery, and ability to return to prior level of activity. Six males and seven females were included in the analysis. Patient age ranged from 17 to 24 years with a mean of 19.7 years. Six patients underwent unilateral lower extremity compartment release, and seven underwent bilateral lower extremity compartment release. The anterior and lateral compartments alone were released in 11 patients (84.6%). Two patients (15.4%) underwent four-compartment releases. Eleven patients (84.6%) were able to return to their previous elite level of sport participation at a mean of 10.6 weeks following surgical fasciotomy. Patients who had four-compartment release had a more than 3.5 week average longer return to full sporting activities (p = 0.011). Fasciotomy is effective in allowing elite athletes with CECS to return to sport.

  9. Spatial H2O2 signaling specificity: H2O2 from chloroplasts and peroxisomes modulates the plant transcriptome differentially.

    Science.gov (United States)

    Sewelam, Nasser; Jaspert, Nils; Van Der Kelen, Katrien; Tognetti, Vanesa B; Schmitz, Jessica; Frerigmann, Henning; Stahl, Elia; Zeier, Jürgen; Van Breusegem, Frank; Maurino, Veronica G

    2014-07-01

    Hydrogen peroxide (H2O2) operates as a signaling molecule in eukaryotes, but the specificity of its signaling capacities remains largely unrevealed. Here, we analyzed whether a moderate production of H2O2 from two different plant cellular compartments has divergent effects on the plant transcriptome. Arabidopsis thaliana overexpressing glycolate oxidase in the chloroplast (Fahnenstich et al., 2008; Balazadeh et al., 2012) and plants deficient in peroxisomal catalase (Queval et al., 2007; Inzé et al., 2012) were grown under non-photorespiratory conditions and then transferred to photorespiratory conditions to foster the production of H2O2 in both organelles. We show that H2O2 originating in a specific organelle induces two types of responses: one that integrates signals independently from the subcellular site of H2O2 production and another that is dependent on the H2O2 production site. H2O2 produced in peroxisomes induces transcripts involved in protein repair responses, while H2O2 produced in chloroplasts induces early signaling responses, including transcription factors and biosynthetic genes involved in production of secondary signaling messengers. There is a significant bias towards the induction of genes involved in responses to wounding and pathogen attack by chloroplastic-produced H2O2, including indolic glucosinolates-, camalexin-, and stigmasterol-biosynthetic genes. These transcriptional responses were accompanied by the accumulation of 4-methoxy-indol-3-ylmethyl glucosinolate and stigmasterol. © The Author 2014. Published by the Molecular Plant Shanghai Editorial Office in association with Oxford University Press on behalf of CSPB and IPPE, SIBS, CAS.

  10. SUBA4: the interactive data analysis centre for Arabidopsis subcellular protein locations.

    Science.gov (United States)

    Hooper, Cornelia M; Castleden, Ian R; Tanz, Sandra K; Aryamanesh, Nader; Millar, A Harvey

    2017-01-04

    The SUBcellular location database for Arabidopsis proteins (SUBA4, http://suba.live) is a comprehensive collection of manually curated published data sets of large-scale subcellular proteomics, fluorescent protein visualization, protein-protein interaction (PPI) as well as subcellular targeting calls from 22 prediction programs. SUBA4 contains an additional 35 568 localizations totalling more than 60 000 experimental protein location claims as well as 37 new suborganellar localization categories. The experimental PPI data has been expanded to 26 327 PPI pairs including 856 PPI localizations from experimental fluorescent visualizations. The new SUBA4 user interface enables users to choose quickly from the filter categories: 'subcellular location', 'protein properties', 'protein-protein interaction' and 'affiliations' to build complex queries. This allows substantial expansion of search parameters into 80 annotation types comprising 1 150 204 new annotations to study metadata associated with subcellular localization. The 'BLAST' tab contains a sequence alignment tool to enable a sequence fragment from any species to find the closest match in Arabidopsis and retrieve data on subcellular location. Using the location consensus SUBAcon, the SUBA4 toolbox delivers three novel data services allowing interactive analysis of user data to provide relative compartmental protein abundances and proximity relationship analysis of PPI and coexpression partners from a submitted list of Arabidopsis gene identifiers. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  11. Linking Subcellular Disturbance to Physiological Behavior and Toxicity Induced by Quantum Dots in Caenorhabditis elegans.

    Science.gov (United States)

    Wang, Qin; Zhou, Yanfeng; Song, Bin; Zhong, Yiling; Wu, Sicong; Cui, Rongrong; Cong, Haixia; Su, Yuanyuan; Zhang, Huimin; He, Yao

    2016-06-01

    The wide-ranging applications of fluorescent semiconductor quantum dots (QDs) have triggered increasing concerns about their biosafety. Most QD-related toxicity studies focus on the subcellular processes in cultured cells or global physiological effects on whole animals. However, it is unclear how QDs affect subcellular processes in living organisms, or how the subcellular disturbance contributes to the overall toxicity. Here the behavior and toxicity of QDs of three different sizes in Caenorhabditis elegans (C. elegans) are systematically investigated at both the systemic and the subcellular level. Specifically, clear size-dependent distribution and toxicity of the QDs in the digestive tract are observed. Short-term exposure of QDs leads to acute toxicity on C. elegans, yet incurring no lasting, irreversible damage. In contrast, chronic exposure of QDs severely inhibits development and shortens lifespan. Subcellular analysis reveals that endocytosis and nutrition storage are disrupted by QDs, which likely accounts for the severe deterioration in growth and longevity. This work reveals that QDs invasion disrupts key subcellular processes in living organisms, and may cause permanent damage to the tissues and organs over long-term retention. The findings provide invaluable information for safety evaluations of QD-based applications and offer new opportunities for design of novel nontoxic nanoprobes. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Signal peptides and protein localization prediction

    DEFF Research Database (Denmark)

    Nielsen, Henrik

    2005-01-01

    In 1999, the Nobel prize in Physiology or Medicine was awarded to Gunther Blobel “for the discovery that proteins have intrinsic signals that govern their transport and localization in the cell”. Since the subcellular localization of a protein is an important clue to its function, the characteriz......In 1999, the Nobel prize in Physiology or Medicine was awarded to Gunther Blobel “for the discovery that proteins have intrinsic signals that govern their transport and localization in the cell”. Since the subcellular localization of a protein is an important clue to its function......, the characterization and prediction of these intrinsic signals – the “zip codes” of proteins – has become a major task in bioinformatics. Here, I will review the most important methods for the prediction of subcellular localization, also known as protein sorting. Owing to the limited space, this review is far from...... complete; especially, applications that are not publicly available on-line are ignored. Generally, there are two approaches to protein localization prediction: signal detection, that is, prediction of the sorting signals themselves, and prediction based on global properties (amino acid composition and...

  13. Subcellular localization of the histidine kinase receptors Sln1p, Nik1p and Chk1p in the yeast CTG clade species Candida guilliermondii.

    Science.gov (United States)

    Foureau, Emilien; Clastre, Marc; Montoya, Erika J Obando; Besseau, Sébastien; Oudin, Audrey; Glévarec, Gaëlle; Simkin, Andrew J; Crèche, Joël; Atehortùa, Lucia; Giglioli-Guivarc'h, Nathalie; Courdavault, Vincent; Papon, Nicolas

    2014-04-01

    Fungal histidine kinase receptors (HKR) sense and transduce many intra- and extracellular signals that regulate a wide range of physiological processes. Candida CTG clade species commonly possess three types of HKR namely Sln1p (type VI), Nik1p (type III) and Chk1p (type X). Although some recent work has demonstrated the potential involvement of HKR in osmoregulation, morphogenesis, sexual development, adaptation to osmotic stresses and drug resistance in distinct Candida species, little data is available in relation to their subcellular distribution within yeast cells. We describe in this work the comparative subcellular localization of class III, VI, and X HKRs in Candida guilliermondii, a yeast CTG clade species of clinical and biotechnological interest. Using a fluorescent protein fusion approach, we showed that C. guilliermondii Sln1p fused to the yellow fluorescent protein (Sln1p-YFP) appeared to be anchored in the plasma membrane. By contrast, both Chk1p-YFP and YFP-Chk1p were localized in the nucleocytosol of C. guilliermondii transformed cells. Furthermore, while Nik1p-YFP fusion protein always displayed a nucleocytosolic localization, we noted that most of the cells expressing YFP-Nik1p fusion protein displayed an aggregated pattern of fluorescence in the cytosol but not in the nucleus. Interestingly, Sln1p-YFP and Nik1p-YFP fusion protein localization changed in response to hyperosmotic stress by rapidly clustering into punctuated structures that could be associated to osmotic stress signaling. To date, this work provides the first insight into the subcellular localization of the three classes of HKR encoded by CTG clade yeast genomes and constitutes original new data concerning this family of receptors. This represents also an essential prerequisite to open a window into the understanding of the global architecture of HKR-mediated signaling pathways in CTG clade species. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Topology Optimization of Spacecraft Transfer Compartment

    Directory of Open Access Journals (Sweden)

    A. A. Borovikov

    2016-01-01

    Full Text Available IntroductionThe subject of this research is topology optimization of the adapter of a spacecraft transfer compartment. The finite element topology optimization [1] is widely used for simple structure elements [6, 7]. It is argued that using this method in conjunction with additive technology (3D - printing it is possible to create construction designs with the best weight characteristics. However, the paper shows that when applying this method to a complex construction design the optimization results are highly sensitive to optimization algorithm parameters. The goal of this research is to study parameters of the topology optimization algorithm and the influence of their variations on results.1.      Problem formulation   A commercial software Altair HyperWorks/OptiStruct (student’s license performed numerical calculations. The paper presents a detailed description of the finite element model.The main features of the proposed model are as follows:-          Simplicity with non-complicated geometry;-          Building a finite element model in terms of computing time minimization;-          Using the lumped mass elements to simulate the impacts of the conjugates on the adapter;-          A limit of material strength, decreased by an order of magnitude, to eliminate stress concentrators;-          The gravitational load applied corresponds to the loads for the Angara-A5 launcher [8]. 2.      Method of solutionA brief description of the SIMP-method realized in the Altair HyperWorks/OptiStruct software is given.3.      ResultsPerformed numerical calculations, and shown the influence of variations of algorithm parameters (DISCRETE, MATINIT, MINDIM, MAXDIM on construction design as well as the parameters SINGLE and SPLIT used to reveal restrictions on manufacturing.Shown that, depending on variations of parameters, an adapter construction strives to «truss» or «shell» type. Described

  15. The role of each compartment in a two-compartment vertical flow reactor for ferruginous mine water treatment.

    Science.gov (United States)

    Yim, G J; Cheong, Y W; Hong, J H; Hur, W

    2014-10-01

    A vertical flow reactor (VFR) has been suggested for remediation of ferruginous mine drainage that passes down through an accreting bed of ochre. However, a VFR has a limited operation time until the system begins to overflow. In this study, a mathematical model was developed as a part of the effort to explore the operation of a VFR, showing dynamic changes in the head differences, ochre depths, and Fe(II)/Fe(III) concentrations in the effluent flow. The analysis showed that VFR operation time extended from 148.5 days to 163 days in an equally divided and to 168.4 days in asymmetrically (0.72:0.28) divided two-compartment VFR, suggesting that an optimum compartment ratio exists that maximizes the VFR operation time. A constant head filtration in the first compartment maximized filtration efficiency and thus prolonged VFR longevity in the two-compartment VFR. Fe(II) oxidation and ochre formation should be balanced with the permeability of the ochre bed to maximize the VFR operation time and minimize the residual Fe(II) in the effluent. Accelerated Fe(II) oxidation affected the optimum ratio of the compartment area and reduced the residual Fe(II) in the effluent. The VFR operation time can be prolonged significantly from 764 days to 3620 days by increasing the rate of ochre formation, much more than by accelerating the Fe(II) oxidation. During the prolonged VFR operation, ochre formed largely in the first compartment, while overflowing mine water with reduced iron content was effectively filtered in the second compartment. These results not only provide a better understanding of VFR operation but also suggest the direction of evolution of two-compartment VFR toward a compact and highly efficient facility integrated with an aerated cascade and with automatic coagulant feeding. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Subcellular distribution of calcium during spermatogenesis of zebrafish, Danio rerio.

    Science.gov (United States)

    Golpour, Amin; Pšenička, Martin; Niksirat, Hamid

    2017-08-01

    Calcium plays a variety of vital regulatory functions in many physiological and biochemical events in the cell. The aim of this study was to describe the ultrastructural distribution of calcium during different developmental stages of spermatogenesis in a model organism, the zebrafish (Danio rerio), using a combined oxalate-pyroantimonate technique. Samples were treated by potassium oxalate and potassium pyroantimonate during two fixation stages and examined using transmission electron microscopy to detect electron dense intracellular calcium. The subcellular distribution of intracellular calcium was characterized in spermatogonium, spermatocyte, spermatid, and spermatozoon stages. The area which is covered by intracellular calcium in different stages was quantified and compared using software. Isolated calcium deposits were mainly detectable in the cytoplasm and the nucleus of the spermatogonium and spermatocyte. In the spermatid, calcium was partially localized in the cytoplasm as isolated deposits. However, most calcium was transformed from isolated deposits into an unbound pool (free calcium) within the nucleus of the spermatid and the spermatozoon. Interestingly, in the spermatozoon, calcium was mainly localized in a form of an unbound pool which was detectable as an electron-dense mass within the nucleus. Also, sporadic calcium deposits were scattered in the midpiece and flagellum. The proportional area which was covered by intracellular calcium increased significantly from early to late stages of spermatogenesis. The extent of the area which was covered by intracellular calcium in the spermatozoon was the highest compared to earlier stages. Calcium deposits were also observed in the somatic cells (Sertoli, myoid, Leydig) of zebrafish testis. The notable changes in the distribution of intracellular calcium of germ cells during different developmental stages of zebrafish spermatogenesis suggest its different homeostasis and physiological functions during the

  17. A sub-cellular viscoelastic model for cell population mechanics.

    Directory of Open Access Journals (Sweden)

    Yousef Jamali

    Full Text Available Understanding the biomechanical properties and the effect of biomechanical force on epithelial cells is key to understanding how epithelial cells form uniquely shaped structures in two or three-dimensional space. Nevertheless, with the limitations and challenges posed by biological experiments at this scale, it becomes advantageous to use mathematical and 'in silico' (computational models as an alternate solution. This paper introduces a single-cell-based model representing the cross section of a typical tissue. Each cell in this model is an individual unit containing several sub-cellular elements, such as the elastic plasma membrane, enclosed viscoelastic elements that play the role of cytoskeleton, and the viscoelastic elements of the cell nucleus. The cell membrane is divided into segments where each segment (or point incorporates the cell's interaction and communication with other cells and its environment. The model is capable of simulating how cells cooperate and contribute to the overall structure and function of a particular tissue; it mimics many aspects of cellular behavior such as cell growth, division, apoptosis and polarization. The model allows for investigation of the biomechanical properties of cells, cell-cell interactions, effect of environment on cellular clusters, and how individual cells work together and contribute to the structure and function of a particular tissue. To evaluate the current approach in modeling different topologies of growing tissues in distinct biochemical conditions of the surrounding media, we model several key cellular phenomena, namely monolayer cell culture, effects of adhesion intensity, growth of epithelial cell through interaction with extra-cellular matrix (ECM, effects of a gap in the ECM, tensegrity and tissue morphogenesis and formation of hollow epithelial acini. The proposed computational model enables one to isolate the effects of biomechanical properties of individual cells and the

  18. Isolated Chronic Exertional Compartment Syndrome of the Lateral Lower Leg

    Science.gov (United States)

    van Zantvoort, Aniek P.M.; de Bruijn, Johan A.; Winkes, Michiel B.; Dielemans, Jeanne P.; van der Cruijsen-Raaijmakers, Marike; Hoogeveen, Adwin R.; Scheltinga, Marc R.

    2015-01-01

    Background: Exercise-induced lower leg pain may be caused by chronic exertional compartment syndrome (CECS). The anterior (ant-CECS) or deep posterior compartment (dp-CECS) is usually affected. Knowledge regarding CECS of the lateral compartment (lat-CECS) is limited. Purpose: To describe demographic characteristics and symptoms in a consecutive series of patients with isolated CECS of the lateral compartment of the leg. Study Design: Case series; Level of evidence, 4. Methods: Since 2001, patients undergoing dynamic intracompartmental pressure (ICP) measurements for suspected CECS in a single institution were prospectively monitored. Individuals with a history possibly associated with lat-CECS and elevated ICP measurements (Pedowitz criteria) were identified. Exclusion criteria were concomitant ipsilateral ant-CECS/dp-CECS, acute compartment syndrome, recent significant trauma, peroneal nerve entrapment, or vascular claudication. Results: During an 11-year time period, a total of 26 patients with isolated lat-CECS fulfilled study criteria (15 females; median age, 21 years; range, 14-48 years). Frequently identified provocative sports were running (n = 4), walking (n = 4), field hockey (n = 3), soccer (n = 3), and volleyball (n = 2). Exercise-induced lateral lower leg pain (92%) and tightness (42%) were often reported. The syndrome was bilateral in almost two-thirds (62%, n = 16). Delay in diagnosis averaged 24 months (range, 2 months to 10 years). Conclusion: Young patients with exercise-induced pain in the lateral portions of the lower leg may suffer from isolated CECS of the lateral compartment. ICP measurements in the lateral compartment in these patients are recommended. PMID:26740955

  19. Outcome of a Specific Compartment Fasciotomy Versus a Complete Compartment Fasciotomy of the Leg in One Patient With Bilateral Anterior Chronic Exertional Compartment Syndrome: A Case Report.

    Science.gov (United States)

    Tjeerdsma, Jason

    2016-01-01

    Chronic exertional compartment syndrome of the leg is a debilitating lower extremity condition in which increased intracompartmental pressure impedes blood flow to the involved compartments of the distal lower extremity, resulting in ischemia and pain. Owing to the lack of success with conservative management, most surgeons perform complete release fasciotomy as the preferred method of fasciotomy to avoid an unsuccessful release or outcome. Studies have been performed regarding the outcomes of complete compartmental release versus specific compartmental release, but no study has been performed comparing complete fasciotomy and compartment-specific fasciotomy in a single patient. The purpose of the present case report was to compare the efficacy of a complete fasciotomy versus a specific fasciotomy in 1 patient with properly diagnosed bilateral anterior compartment chronic exertional compartment syndrome with an 18-month follow-up period. The Lower Extremity Functional Scale and both subscales of the Foot and Ankle Ability Measure were administered to assess the functional outcomes. Circumferential measurements and range of motion photographs were taken to compare the objective data throughout the recovery process. In general, the range of motion, circumferential measurements, and functional outcome measure scores were better for the specific compartmental fasciotomy leg than for the complete fasciotomy leg during the recovery period. The overall functional outcomes were the same for both surgical approaches, with the specific fasciotomy leg returning to baseline function 13 to 23 days before the complete fasciotomy leg. The outcomes remained unchanged 18 months after surgery. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  20. Studying Coxiella burnetii Type IV Substrates in the Yeast Saccharomyces cerevisiae: Focus on Subcellular Localization and Protein Aggregation.

    Science.gov (United States)

    Rodríguez-Escudero, María; Cid, Víctor J; Molina, María; Schulze-Luehrmann, Jan; Lührmann, Anja; Rodríguez-Escudero, Isabel

    2016-01-01

    Coxiella burnetii is a Gram-negative obligate parasitic bacterium that causes the disease Q-fever in humans. To establish its intracellular niche, it utilizes the Icm/Dot type IVB secretion system (T4BSS) to inject protein effectors into the host cell cytoplasm. The host targets of most cognate and candidate T4BSS-translocated effectors remain obscure. We used the yeast Saccharomyces cerevisiae as a model to express and study six C. burnetii effectors, namely AnkA, AnkB, AnkF, CBU0077, CaeA and CaeB, in search for clues about their role in C. burnetii virulence. When ectopically expressed in HeLa cells, these effectors displayed distinct subcellular localizations. Accordingly, GFP fusions of these proteins produced in yeast also decorated distinct compartments, and most of them altered cell growth. CaeA was ubiquitinated both in yeast and mammalian cells and, in S. cerevisiae, accumulated at juxtanuclear quality-control compartments (JUNQs) and insoluble protein deposits (IPODs), characteristic of aggregative or misfolded proteins. AnkA, which was not ubiquitinated, accumulated exclusively at the IPOD. CaeA, but not AnkA or the other effectors, caused oxidative damage in yeast. We discuss that CaeA and AnkA behavior in yeast may rather reflect misfolding than recognition of conserved targets in the heterologous system. In contrast, CBU0077 accumulated at vacuolar membranes and abnormal ER extensions, suggesting that it interferes with vesicular traffic, whereas AnkB associated with the yeast nucleolus. Both effectors shared common localization features in HeLa and yeast cells. Our results support the idea that C. burnetii T4BSS effectors manipulate multiple host cell targets, which can be conserved in higher and lower eukaryotic cells. However, the behavior of CaeA and AnkA prompt us to conclude that heterologous protein aggregation and proteostatic stress can be a limitation to be considered when using the yeast model to assess the function of bacterial effectors.

  1. Subcellular targeting of bacterial CusF enhances Cu accumulation and alters root to shoot Cu translocation in arabidopsis.

    Science.gov (United States)

    Yu, Pengli; Yuan, Jinhong; Deng, Xin; Ma, Mi; Zhang, Haiyan

    2014-09-01

    Copper (Cu) is an important environmental pollutant that exerts harmful effects on all living organisms when in excess. In an effort to remove this toxin in situ, a bacterial Cu-binding protein gene CusF was engineered to target CusF for secretion to the cell wall and vacuoles and for accumulation in the cytoplasm. Analysis of transgenic Arabidopsis plants showed that CusF was functionally active and that plants expressing cell wall- (CusFcw transgenic lines) or vacuole-targeted CusF (CusFvac transgenic lines) were more resistant to Cu excess than untransformed plants and plants with cytoplasmic CusF (CusFcyto transgenic lines). Under short-term (48 h) exposure to Cu excess, CusFcw transgenic lines showed up to 2-fold increased Cu accumulation in roots compared with the untransformed plants; however, CusFcyto lines and the wild-type plants had similar Cu concentrations in both roots and shoots. Under long-term (40 d) exposure to Cu excess, all transgenic lines accumulated more Cu (up to 3-fold) in roots than the untransformed plants, whereas only CusFcyto lines showed a marked increase (∼3-fold of the wild-type plants) of Cu accumulation in shoots. In addition, expression of CusF in the cytosol dramatically enhanced Cu transport from roots to shoots when compared with plants with secretory pathway-targeted CusF. Our results demonstrate the feasibility of Cu tolerance and accumulation by engineering Cu-binding proteins targetable to subcellular compartments and provide new insights into the multifaceted mechanisms of Cu partitioning between roots and shoots. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  2. Surgical Treatment of Chronic Exertional Compartment Syndrome in Pediatric Patients.

    Science.gov (United States)

    Beck, Jennifer J; Tepolt, Frances A; Miller, Patricia E; Micheli, Lyle J; Kocher, Mininder S

    2016-10-01

    Chronic exertional compartment syndrome (CECS) is a cause of leg pain in running athletes and is treated with fasciotomy after failure of nonoperative management. CECS is being seen with increased frequency in younger patients. The demographics and outcomes of fasciotomy for CECS in pediatric patients, including risk factors for treatment failure, have not been described. To describe characteristics of pediatric patients with CECS and determine surgical outcomes of the condition in this population. Case series; Level of evidence, 4. A retrospective review was performed for patients 18 years and younger treated surgically for CECS with compartment release at a single institution from 1995 to 2014. Demographic and condition characteristics, operative procedure, postoperative course, and clinical outcomes were recorded for 286 legs of 155 patients. Compartment pressure testing using the Pedowitz criteria confirmed the diagnosis in all patients. A total of 155 patients were included in the study (average patient age at presentation, 16.4 ± 1.38 years); 136 (88%) were female. All 155 patients presented with leg pain; of these patients, 8 (5%) also had neurologic symptoms, and 131 (85%) presented with bilateral symptoms requiring bilateral compartment release. Symptoms were chronic in nature, with duration over 1 year in 63% of patients. The primary sport was most commonly reported as running (25%), soccer (23%), or field hockey (12%); 50% of patients were multisport athletes. Of 286 legs, 138 (48%) had only anterior and/or lateral compartments released, while 84 (29.4%) had all 4 compartments released. Documented return to sport was seen in 79.5% of patients. Outcomes analysis was performed for 250 of 286 legs. Of these 250 legs, 47 (18.8%) had recurrent CECS requiring reoperation at a median of 1.3 years (interquartile range, 0.8-3.5) after initial compartment release. For each additional month between presentation and release, the odds of recurrence decreased by 12

  3. Elevated compartment pressures from copperhead envenomation successfully treated with antivenin.

    Science.gov (United States)

    Mazer-Amirshahi, Maryann; Boutsikaris, Amy; Clancy, Cathleen

    2014-01-01

    Copperhead envenomation causes local soft tissue effects; however, associated compartment syndrome is rare. We report a case of a 17-month-old with significantly elevated compartment pressures successfully treated with antivenin and supportive care. A 17-month-old girl sustained a copperhead bite to the foot and presented with circumferential edema, erythema, and ecchymosis of the foot and distal ankle. The patient had palpable pulses and was neurologically intact. Four vials of Crotalidae polyvalent immune Fab was initiated and additional doses were administered in an attempt to achieve local control. Within 10 h of presentation, the patient's edema extended to the groin, although sensation was maintained and pulses were documented by Doppler. Lower-extremity compartment pressures were measured and were most notable for an anterior pressure of 85 mm Hg, despite having received 12 vials of antivenin. Fasciotomy was deferred and the patient received two additional six-vial doses of antivenin to achieve local control. Compartment pressures improved with a 2.2-cm mean decrease in limb diameter within 48 h. Maintenance dosing was initiated and the patient ultimately received a total of 26 vials of antivenin. The patient did not develop significant coagulopathy or thrombocytopenia. Swelling continued to improve with return of limb function. In this case, early and aggressive treatment with antivenin may have avoided invasive fasciotomy, and its use should be considered in patients with copperhead envenomation and significantly elevated compartment pressures. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Numerical modelling of crural fascia mechanical interaction with muscular compartments.

    Science.gov (United States)

    Pavan, Piero G; Pachera, Paola; Natali, Arturo N

    2015-05-01

    The interaction of the crural fascia with muscular compartments and surrounding tissues can be at the origin of different pathologies, such as compartment syndrome. This pathology consists in the onset of excessive intracompartmental pressure, which can have serious consequences for the patient, compromising blood circulation. The investigation of compartment syndrome etiology also takes into account the alteration of crural fascia mechanical properties as a cause of the syndrome, where the fascial stiffening would result in the rise of intracompartmental pressure. This work presents a computational approach toward evaluating some biomechanical aspects of the problem, within the context of a more global viewpoint. Finite element analyses of the interaction phenomena of the crural fascia with adjacent regions are reported here. This study includes the effects of a fascial stiffness increase along the proximal-distal direction and their possible clinical implications. Furthermore, the relationship between different pre-strain levels of the crural fascia in the proximal-distal direction and the rise of internal pressure in muscular compartments are considered. The numerical analyses can clarify which aspects could be directly implied in the rise of compartment syndrome, leading to greater insight into muscle-fascia mechanical phenomena, as well as promoting experimental investigation and clinical analysis of the syndrome. © IMechE 2015.

  5. LocateP: Genome-scale subcellular-location predictor for bacterial proteins

    Directory of Open Access Journals (Sweden)

    Zhou Miaomiao

    2008-03-01

    Full Text Available Abstract Background In the past decades, various protein subcellular-location (SCL predictors have been developed. Most of these predictors, like TMHMM 2.0, SignalP 3.0, PrediSi and Phobius, aim at the identification of one or a few SCLs, whereas others such as CELLO and Psortb.v.2.0 aim at a broader classification. Although these tools and pipelines can achieve a high precision in the accurate prediction of signal peptides and transmembrane helices, they have a much lower accuracy when other sequence characteristics are concerned. For instance, it proved notoriously difficult to identify the fate of proteins carrying a putative type I signal peptidase (SPIase cleavage site, as many of those proteins are retained in the cell membrane as N-terminally anchored membrane proteins. Moreover, most of the SCL classifiers are based on the classification of the Swiss-Prot database and consequently inherited the inconsistency of that SCL classification. As accurate and detailed SCL prediction on a genome scale is highly desired by experimental researchers, we decided to construct a new SCL prediction pipeline: LocateP. Results LocateP combines many of the existing high-precision SCL identifiers with our own newly developed identifiers for specific SCLs. The LocateP pipeline was designed such that it mimics protein targeting and secretion processes. It distinguishes 7 different SCLs within Gram-positive bacteria: intracellular, multi-transmembrane, N-terminally membrane anchored, C-terminally membrane anchored, lipid-anchored, LPxTG-type cell-wall anchored, and secreted/released proteins. Moreover, it distinguishes pathways for Sec- or Tat-dependent secretion and alternative secretion of bacteriocin-like proteins. The pipeline was tested on data sets extracted from literature, including experimental proteomics studies. The tests showed that LocateP performs as well as, or even slightly better than other SCL predictors for some locations and outperforms

  6. Protein targeting to subcellular organelles via MRNA localization.

    Science.gov (United States)

    Weis, Benjamin L; Schleiff, Enrico; Zerges, William

    2013-02-01

    Cells have complex membranous organelles for the compartmentalization and the regulation of most intracellular processes. Organelle biogenesis and maintenance requires newly synthesized proteins, each of which needs to go from the ribosome translating its mRNA to the correct membrane for insertion or transclocation to an a organellar subcompartment. Decades of research have revealed how proteins are targeted to the correct organelle and translocated across one or more organelle membranes ro the compartment where they function. The paradigm examples involve interactions between a peptide sequence in the protein, localization factors, and various membrane embedded translocation machineries. Membrane translocation is either cotranslational or posttranslational depending on the protein and target organelle. Meanwhile research in embryos, neurons and yeast revealed an alternative targeting mechanism in which the mRNA is localized and only then translated to synthesize the protein in the correct location. In these cases, the targeting information is coded by the cis-acting sequences in the mRNA ("Zipcodes") that interact with localization factors and, in many cases, are transported by the molecular motors on the cytoskeletal filaments. Recently, evidence has been found for this "mRNA based" mechanism in organelle protein targeting to endoplasmic reticulum, mitochondria, and the photosynthetic membranes within chloroplasts. Here we review known and potential roles of mRNA localization in protein targeting to and within organelles. This article is part of a Special Issue entitled: Protein Import and Quality Control in Mitochondria and Plastids.

  7. Measurement of compartment elasticity using pressure related ultrasound: a method to identify patients with potential compartment syndrome.

    Science.gov (United States)

    Sellei, R M; Hingmann, S J; Kobbe, P; Weber, C; Grice, J E; Zimmerman, F; Jeromin, S; Gansslen, A; Hildebrand, F; Pape, H C

    2015-01-01

    PURPOSE OF THE STUDY Decision-making in treatment of an acute compartment syndrome is based on clinical assessment, supported by invasive monitoring. Thus, evolving compartment syndrome may require repeated pressure measurements. In suspected cases of potential compartment syndromes clinical assessment alone seems to be unreliable. The objective of this study was to investigate the feasibility of a non-invasive application estimating whole compartmental elasticity by ultrasound, which may improve accuracy of diagnostics. MATERIAL AND METHODS In an in-vitro model, using an artificial container simulating dimensions of the human anterior tibial compartment, intracompartmental pressures (p) were raised subsequently up to 80 mm Hg by infusion of saline solution. The compartmental depth (mm) in the cross-section view was measured before and after manual probe compression (100 mm Hg) upon the surface resulting in a linear compartmental displacement (Δd). This was repeated at rising compartmental pressures. The resulting displacements were related to the corresponding intra-compartmental pressures simulated in our model. A hypothesized relationship between pressures related compartmental displacement and the elasticity at elevated compartment pressures was investigated. RESULTS With rising compartmental pressures, a non-linear, reciprocal proportional relation between the displacement (mm) and the intra-compartmental pressure (mm Hg) occurred. The Pearson's coefficient showed a high correlation (r2 = -0.960). The intraobserver reliability value kappa resulted in a statistically high reliability (κ = 0.840). The inter-observer value indicated a fair reliability (κ = 0.640). CONCLUSIONS Our model reveals that a strong correlation between compartmental strain displacements assessed by ultrasound and the intra-compartmental pressure changes occurs. Further studies are required to prove whether this assessment is transferable to human muscle tissue. Determining the complete

  8. F-box protein specificity for g1 cyclins is dictated by subcellular localization.

    Directory of Open Access Journals (Sweden)

    Benjamin D Landry

    Full Text Available Levels of G1 cyclins fluctuate in response to environmental cues and couple mitotic signaling to cell cycle entry. The G1 cyclin Cln3 is a key regulator of cell size and cell cycle entry in budding yeast. Cln3 degradation is essential for proper cell cycle control; however, the mechanisms that control Cln3 degradation are largely unknown. Here we show that two SCF ubiquitin ligases, SCF(Cdc4 and SCF(Grr1, redundantly target Cln3 for degradation. While the F-box proteins (FBPs Cdc4 and Grr1 were previously thought to target non-overlapping sets of substrates, we find that Cdc4 and Grr1 each bind to all 3 G1 cyclins in cell extracts, yet only Cln3 is redundantly targeted in vivo, due in part to its nuclear localization. The related cyclin Cln2 is cytoplasmic and exclusively targeted by Grr1. However, Cdc4 can interact with Cdk-phosphorylated Cln2 and target it for degradation when cytoplasmic Cdc4 localization is forced in vivo. These findings suggest that Cdc4 and Grr1 may share additional redundant targets and, consistent with this possibility, grr1Δ cdc4-1 cells demonstrate a CLN3-independent synergistic growth defect. Our findings demonstrate that structurally distinct FBPs are capable of interacting with some of the same substrates; however, in vivo specificity is achieved in part by subcellular localization. Additionally, the FBPs Cdc4 and Grr1 are partially redundant for proliferation and viability, likely sharing additional redundant substrates whose degradation is important for cell cycle progression.

  9. A celiac cellular phenotype, with altered LPP sub-cellular distribution, is inducible in controls by the toxic gliadin peptide P31-43.

    Directory of Open Access Journals (Sweden)

    Merlin Nanayakkara

    Full Text Available Celiac disease (CD is a frequent inflammatory intestinal disease, with a genetic background, caused by gliadin-containing food. Undigested gliadin peptides P31-43 and P57-68 induce innate and adaptive T cell-mediated immune responses, respectively. Alterations in the cell shape and actin cytoskeleton are present in celiac enterocytes, and gliadin peptides induce actin rearrangements in both the CD mucosa and cell lines. Cell shape is maintained by the actin cytoskeleton and focal adhesions, sites of membrane attachment to the extracellular matrix. The locus of the human Lipoma Preferred Partner (LPP gene was identified as strongly associated with CD using genome-wide association studies (GWAS. The LPP protein plays an important role in focal adhesion architecture and acts as a transcription factor in the nucleus. In this study, we examined the hypothesis that a constitutive alteration of the cell shape and the cytoskeleton, involving LPP, occurs in a cell compartment far from the main inflammation site in CD fibroblasts from skin explants. We analyzed the cell shape, actin organization, focal adhesion number, focal adhesion proteins, LPP sub-cellular distribution and adhesion to fibronectin of fibroblasts obtained from CD patients on a Gluten-Free Diet (GFD and controls, without and with treatment with A-gliadin peptide P31-43. We observed a "CD cellular phenotype" in these fibroblasts, characterized by an altered cell shape and actin organization, increased number of focal adhesions, and altered intracellular LPP protein distribution. The treatment of controls fibroblasts with gliadin peptide P31-43 mimics the CD cellular phenotype regarding the cell shape, adhesion capacity, focal adhesion number and LPP sub-cellular distribution, suggesting a close association between these alterations and CD pathogenesis.

  10. Predict subcellular locations of singleplex and multiplex proteins by semi-supervised learning and dimension-reducing general mode of Chou's PseAAC.

    Science.gov (United States)

    Pacharawongsakda, Eakasit; Theeramunkong, Thanaruk

    2013-12-01

    Predicting protein subcellular location is one of major challenges in Bioinformatics area since such knowledge helps us understand protein functions and enables us to select the targeted proteins during drug discovery process. While many computational techniques have been proposed to improve predictive performance for protein subcellular location, they have several shortcomings. In this work, we propose a method to solve three main issues in such techniques; i) manipulation of multiplex proteins which may exist or move between multiple cellular compartments, ii) handling of high dimensionality in input and output spaces and iii) requirement of sufficient labeled data for model training. Towards these issues, this work presents a new computational method for predicting proteins which have either single or multiple locations. The proposed technique, namely iFLAST-CORE, incorporates the dimensionality reduction in the feature and label spaces with co-training paradigm for semi-supervised multi-label classification. For this purpose, the Singular Value Decomposition (SVD) is applied to transform the high-dimensional feature space and label space into the lower-dimensional spaces. After that, due to limitation of labeled data, the co-training regression makes use of unlabeled data by predicting the target values in the lower-dimensional spaces of unlabeled data. In the last step, the component of SVD is used to project labels in the lower-dimensional space back to those in the original space and an adaptive threshold is used to map a numeric value to a binary value for label determination. A set of experiments on viral proteins and gram-negative bacterial proteins evidence that our proposed method improve the classification performance in terms of various evaluation metrics such as Aiming (or Precision), Coverage (or Recall) and macro F-measure, compared to the traditional method that uses only labeled data.

  11. Reversible G Protein βγ9 Distribution-Based Assay Reveals Molecular Underpinnings in Subcellular, Single-Cell, and Multicellular GPCR and G Protein Activity.

    Science.gov (United States)

    Senarath, Kanishka; Ratnayake, Kasun; Siripurapu, Praneeth; Payton, John L; Karunarathne, Ajith

    2016-12-06

    Current assays to measure the activation of G protein coupled receptors (GPCRs) and G proteins are time-consuming, indirect, and expensive. Therefore, an efficient method which directly measures the ability of a ligand to govern GPCR-G protein interactions can help to understand the molecular underpinnings of the associated signaling. A live cell imaging-based approach is presented here to directly measure ligand-induced GPCR and G protein activity in real time. The number of active GPCRs governs G protein heterotrimer (αβγ) dissociation, thereby controlling the concentration of free βγ subunits. The described γ9 assay measures the GPCR activation-induced extent of the reversible βγ9 subunit exchange between the plasma membrane (PM) and internal membranes (IMs). Confocal microscopy-based γ9 assay quantitatively determines the concentration dependency of ligands on GPCR activation. Demonstrating the high-throughput screening (HTS) adaptability, the γ9 assay performed using an imaging plate reader measures the ligand-induced GPCR activation. This suggests that the γ9 assay can be employed to screen libraries of compounds for their ability to activate GPCRs. Together with subcellular optogenetics, the spatiotemporal sensitivity of the γ9 assay permits experimental determination of the limits of spatially restricted activation of GPCRs and G proteins in subcellular regions of single cells. This assay works effectively for GPCRs coupled to αi/o and αs heterotrimers, including light-sensitive GPCRs. In addition, computational modeling of experimental data from the assay is used to decipher intricate molecular details of the GPCR-G protein activation process. Overall, the γ9 assay provides a robust strategy for quantitative as well as qualitative determination of GPCR and G protein function on a single-cell, multicell, and subcellular level. This assay not only provides information about the inner workings of the signaling pathway, but it also strengthens

  12. Differential distribution and function of GABABRs in somato-dendritic and axonal compartments of principal cells and interneurons in cortical circuits.

    Science.gov (United States)

    Kulik, Ákos; Booker, Sam A; Vida, Imre

    2017-10-14

    GABABRs are highly expressed in cortical circuits, controlling neuronal excitability and synaptic transmission in both principal cells and inhibitory interneurons. Light and electron microscopic studies confirmed the wide distribution of receptors and revealed cell type-specific quantitative differences in their cellular and subcellular distributions. At the subcellular level, GABABRs are abundant at the peri- and extrasynaptic membrane of somato-dendritic compartments and to lower levels in the axon terminals of both cortical excitatory principal cells and inhibitory interneurons. Differences in the surface densities are particularly prominent between neurochemically-defined interneuron types. Whole-cell recordings further demonstrated that GABABRs differentially mediate post- and presynaptic inhibition in principal cells and various GABAergic interneurons by preferentially modulating postsynaptic G-protein-coupled inwardly rectifying K+ (Kir3) channels and presynaptic high voltage-activated Ca2+ (Cav) channels. These data convergently indicate that GABABRs not only control the overall level of neuronal excitability and activity, but can also fine tune the activation and interactions of excitatory and inhibitory neurons in cortical circuits. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Identification and functional analysis of NOL7 nuclear and nucleolar localization signals

    Directory of Open Access Journals (Sweden)

    Lingen Mark W

    2010-09-01

    Full Text Available Abstract Background NOL7 is a candidate tumor suppressor that localizes to a chromosomal region 6p23. This locus is frequently lost in a number of malignancies, and consistent loss of NOL7 through loss of heterozygosity and decreased mRNA and protein expression has been observed in tumors and cell lines. Reintroduction of NOL7 into cells resulted in significant suppression of in vivo tumor growth and modulation of the angiogenic phenotype. Further, NOL7 was observed to localize to the nucleus and nucleolus of cells. However, the mechanisms regulating its subcellular localization have not been elucidated. Results An in vitro import assay demonstrated that NOL7 requires cytosolic machinery for active nuclear transport. Using sequence homology and prediction algorithms, four putative nuclear localization signals (NLSs were identified. NOL7 deletion constructs and cytoplasmic pyruvate kinase (PK fusion proteins confirmed the functionality of three of these NLSs. Site-directed mutagenesis of PK fusions and full-length NOL7 defined the minimal functional regions within each NLS. Further characterization revealed that NLS2 and NLS3 were critical for both the rate and efficiency of nuclear targeting. In addition, four basic clusters within NLS2 and NLS3 were independently capable of nucleolar targeting. The nucleolar occupancy of NOL7 revealed a complex balance of rapid nucleoplasmic shuttling but low nucleolar mobility, suggesting NOL7 may play functional roles in both compartments. In support, targeting to the nucleolar compartment was dependent on the presence of RNA, as depletion of total RNA or rRNA resulted in a nucleoplasmic shift of NOL7. Conclusions These results identify the minimal sequences required for the active targeting of NOL7 to the nucleus and nucleolus. Further, this work characterizes the relative contribution of each sequence to NOL7 nuclear and nucleolar dynamics, the subnuclear constituents that participate in this targeting, and

  14. Rapid and dynamic subcellular reorganization following mechanical stimulation of Arabidopsis epidermal cells mimics responses to fungal and oomycete attack

    Directory of Open Access Journals (Sweden)

    Takemoto Daigo

    2008-06-01

    Full Text Available Abstract Background Plant cells respond to the presence of potential fungal or oomycete pathogens by mounting a basal defence response that involves aggregation of cytoplasm, reorganization of cytoskeletal, endomembrane and other cell components and development of cell wall appositions beneath the infection site. This response is induced by non-adapted, avirulent and virulent pathogens alike, and in the majority of cases achieves penetration resistance against the microorganism on the plant surface. To explore the nature of signals that trigger this subcellular response and to determine the timing of its induction, we have monitored the reorganization of GFP-tagged actin, microtubules, endoplasmic reticulum (ER and peroxisomes in Arabidopsis plants – after touching the epidermal surface with a microneedle. Results Within 3 to 5 minutes of touching the surface of Arabidopsis cotyledon epidermal cells with fine glass or tungsten needles, actin microfilaments, ER and peroxisomes began to accumulate beneath the point of contact with the needle. Formation of a dense patch of actin was followed by focusing of actin cables on the site of contact. Touching the cell surface induced localized depolymerization of microtubules to form a microtubule-depleted zone surrounding a dense patch of GFP-tubulin beneath the needle tip. The concentration of actin, GFP-tubulin, ER and peroxisomes remained focused on the contact site as the needle moved across the cell surface and quickly dispersed when the needle was removed. Conclusion Our results show that plant cells can detect the gentle pressure of a microneedle on the epidermal cell surface and respond by reorganizing subcellular components in a manner similar to that induced during attack by potential fungal or oomycete pathogens. The results of our study indicate that during plant-pathogen interactions, the basal defence response may be induced by the plant's perception of the physical force exerted by the

  15. Well-leg compartment syndrome after gynecological laparoscopic surgery

    DEFF Research Database (Denmark)

    Boesgaard-Kjer, Diana H; Boesgaard-Kjer, Daniel; Kjer, Jens Jørgen

    2013-01-01

    Well-leg compartment syndrome in the lower extremities after surgery in the lithotomy position is a rare but severe complication requiring early diagnosis and intervention. Several circumstances predispose to this condition as a consequence of increased intra-compartmental pressure......, such as positioning of the legs during operation (lithotomy and Lloyd-Davies positions), a prolonged operation, external compression and vascular insults, both pre- and intra-operatively. To prevent well-leg compartment syndrome it is important to improve knowledge of the condition among surgeons and nursing staff....... Potential risk factors and preventive initiatives are listed to reduce the risk in future patients. We describe two patients who underwent gynecologic laparoscopic surgery and postoperatively developed well-leg compartment syndrome....

  16. Acute Compartment Syndrome of the Limbs: Current Concepts and Management

    Science.gov (United States)

    Mabvuure, Nigel Tapiwa; Malahias, Marco; Hindocha, Sandip; Khan, Wasim; Juma, Ali

    2012-01-01

    Acute compartment syndrome (ACS) of the limb refers to a constellation of symptoms, which occur following a rise in the pressure inside a limb muscle compartment. A failure or delay in recognising ACS almost invariably results in adverse outcomes for patients. Unrecognised ACS can leave patients with nonviable limbs requiring amputation and can also be life–threatening. Several clinical features indicate ACS. Where diagnosis is unclear there are several techniques for measuring intracompartmental pressure described in this review. As early diagnosis and fasciotomy are known to be the best determinants of good outcomes, it is important that surgeons are aware of the features that make this diagnosis likely. This clinical review discusses current knowledge on the relevant clinical anatomy, aetiology, pathophysiology, risk factors, clinical features, diagnostic procedures and management of an acute presentation of compartment syndrome. PMID:23248724

  17. Exercise Induced Rhabdomyolysis with Compartment Syndrome and Renal Failure

    Directory of Open Access Journals (Sweden)

    Mary Colleen Bhalla

    2014-01-01

    Full Text Available Exertional rhabdomyolysis is sequela that is occasionally seen after strenuous exercise. The progression to compartment syndrome or renal failure is a rare complication that requires prompt recognition and treatment to prevent morbidity (Giannoglou et al. 2007. We present a case of a 22-year-old college football player who presented to the emergency department (ED after a typical leg workout as part of his weight conditioning. He was found to have rhabdomyolysis with evidence of renal insufficiency. His condition progressed to bilateral compartment syndrome and renal failure requiring dialysis. After bilateral fasciotomies were performed he had resolution of his compartment syndrome. He continued to be dialysis dependent and had no return of his renal function at discharge 12 days after admission.

  18. Distinct MicroRNA Subcellular Size and Expression Patterns in Human Cancer Cells

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    Beibei Chen

    2012-01-01

    Full Text Available Introduction. Small noncoding RNAs have important regulatory functions in different cell pathways. It is believed that most of them mainly play role in gene post-transcriptional regulation in the cytoplasm. Recent evidence suggests miRNA and siRNA activity in the nucleus. Here, we show distinct genome-wide sub-cellular localization distribution profiles of small noncoding RNAs in human breast cancer cells. Methods. We separated breast cancer cell nuclei from cytoplasm, and identified small RNA sequences using a high-throughput sequencing platform. To determine the relationship between miRNA sub-cellular distribution and cancer progression, we used microarray analysis to examine the miRNA expression levels in nucleus and cytoplasm of three human cell lines, one normal breast cell line and two breast cancer cell lines. Logistic regression and SVM were used for further analysis. Results. The sub-cellular distribution of small noncoding RNAs shows that numerous miRNAs and their isoforms (isomiR not only locate to the cytoplasm but also appeare in the nucleus. Subsequent microarray analyses indicated that the miRNA nuclear-cytoplasmic-ratio is a significant characteristic of different cancer cell lines. Conclusions. Our results indicate that the sub-cellular distribution is important for miRNA function, and that the characterization of the small RNAs sub-cellular localizome may contribute to cancer research and diagnosis.

  19. Sub-cellular force microscopy in single normal and cancer cells.

    Science.gov (United States)

    Babahosseini, H; Carmichael, B; Strobl, J S; Mahmoodi, S N; Agah, M

    2015-08-07

    This work investigates the biomechanical properties of sub-cellular structures of breast cells using atomic force microscopy (AFM). The cells are modeled as a triple-layered structure where the Generalized Maxwell model is applied to experimental data from AFM stress-relaxation tests to extract the elastic modulus, the apparent viscosity, and the relaxation time of sub-cellular structures. The triple-layered modeling results allow for determination and comparison of the biomechanical properties of the three major sub-cellular structures between normal and cancerous cells: the up plasma membrane/actin cortex, the mid cytoplasm/nucleus, and the low nuclear/integrin sub-domains. The results reveal that the sub-domains become stiffer and significantly more viscous with depth, regardless of cell type. In addition, there is a decreasing trend in the average elastic modulus and apparent viscosity of the all corresponding sub-cellular structures from normal to cancerous cells, which becomes most remarkable in the deeper sub-domain. The presented modeling in this work constitutes a unique AFM-based experimental framework to study the biomechanics of sub-cellular structures. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Kidney compartment model. [Mathematical model for iodohippurate distribution as a function of time

    Energy Technology Data Exchange (ETDEWEB)

    Gullberg, G.T.

    1976-09-01

    A multiparameter kidney compartment model which quantitates the amount of iodohippurate concentration as a function of time in the blood, tissue, kidneys and bladder is developed from a system of differential equations which represent first order kinetics. The kinetic data are obtained using a gamma camera and an HP5407 computer system which allows one to delineate areas of interest for the blood and tissue, kidneys, and bladder thus separating the data into four data sets. The estimated tubular transit times have a high ratio of the signal to the variance whereas the estimates of the amount of iodohippurate in the blood, tissue and kidneys have a low ratio of the signal to the variance. Application of this model to patient data requires better statistics than available with conventional /sup 131/I-hippurate doses; thus a true test of the efficacy awaits availability of /sup 123/I-hippurate.

  1. Orientationally invariant metrics of apparent compartment eccentricity from double pulsed field gradient diffusion experiments

    DEFF Research Database (Denmark)

    Jespersen, Sune Nørhøj; Lundell, Henrik; Sønderby, Casper Kaae

    2013-01-01

    orientation dispersion when applied to macroscopically anisotropic systems. Here we propose a new framework, the d-PFG 5-design, to enable rotationally invariant estimation of double wave vector diffusion metrics (d-PFG). The method is based on the idea that an appropriate orientational average of the signal...... pairs of diffusion wave vectors (the d-PFG 5-design) facilitating a theoretically exact determination of the fourth order Taylor or cumulant expansion of the orientationally averaged signal. The d-PFG 5-design is evaluated with numerical simulations and ex vivo high field diffusion MRI experiments...... in a nonhuman primate brain. Specifically, we demonstrate rotational invariance when estimating compartment eccentricity, which we show offers new microstructural information, complementary to that of fractional anisotropy (FA) from diffusion tensor imaging (DTI). The imaging observations are supported by a new...

  2. Acute and recurrent effort-related compartment syndrome in sports.

    Science.gov (United States)

    Martens, M A; Moeyersoons, J P

    1990-01-01

    An effort-related compartmental syndrome is a condition in which increased pressure in a muscle compartment impedes blood flow and compromises metabolic demands of the tissues within that space. One can clinically distinguish acute irreversible and chronic reversible types. The aetiology relates in most instances to a limiting noncompliant fascia surrounding the affected muscle compartment. Sports activity leads to increased muscle volume and if there is a noncompliant fascia this will result in an excessive intracompartmental pressure which interferes with muscle blood flow. As a consequence of a reduced intracompartmental blood flow a reversible (recurrent) or irreversible (acute) exercise ischaemia, a so-called 'compartmental syndrome' occurs. A compartment syndrome is typically encountered in the lower leg, but it can be also observed in the upper leg and even in the forearm. Clinical history plays a key role in the diagnosis. Pain, muscle tightness and cramp-like feeling are the most common complaints. Weakness, paralysis and numbness are seen, especially in the acute syndrome. Symptoms appear at a certain intensity of activity and disappear at rest in the chronic compartment syndrome, but in the acute type pain will persist and will be severe. It is clearly an effort-related pain syndrome. Physical examination is not always useful in diagnosing a recurrent syndrome, but in the acute syndrome one will find high sensitivity to pressure and tenseness over the involved muscle compartment. Decreased or loss of active motion and sensation in the involved compartment are frequently seen. Tissue pressure monitoring can confirm the diagnosis for both types.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. A HaloTag® method for assessing the retrograde axonal transport of the p75 neurotrophin receptor and other proteins in compartmented cultures of rat sympathetic neurons.

    Science.gov (United States)

    Mok, Sue-Ann; Lund, Karen; Lapointe, Paul; Campenot, Robert B

    2013-03-30

    We have adapted HaloTag® (HT) technology for use in compartmented cultures of rat sympathetic neurons in order to provide a technique that can be broadly applied to studies of the retrograde transport of molecules that play roles in neurotrophin signaling. Transfected neurons expressing HT protein alone, HT protein fused to the p75 neurotrophin receptor (p75NTR) or HT protein fused to tubulin α-1B were maintained in compartmented cultures in which cell bodies and proximal axons of rat sympathetic neurons reside in proximal compartments and their distal axons extend into distal compartments. HT ligand containing a fluorescent tetramethylrhodamine (TMR) label was applied either in the distal compartments or the proximal compartments, and the transport of labeled proteins was assayed by gel fluorescence imaging and TMR immunoblot. HT protein expressed alone displayed little or no retrograde transport. HT protein fused to either the intracellular C-terminus or the extracellular N-terminus of p75NTR was retrogradely transported. The retrograde transport of p75NTR was augmented when the distal axons were provided with nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) or antibodies to BDNF. The anterograde transport of HT protein fused to the N-terminus of tubulin α-1B was also demonstrated. We conclude that retrograde transport of HT fusion proteins provides a powerful and novel approach in studies of axonal transport. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Complications After Fasciotomy Revision and Delayed Compartment Release in Combat Patients

    Science.gov (United States)

    2008-02-01

    were three carpal tunnels , one forearm flexor compartment, one triceps compartment, and one hypothenar compartment. Of the 51 patients, who under- went...anatomy making fas- ciotomies challenging. Rapid air evacua- tion may delay treatment of patients with evolving extremity compartment syndrome . We...of major amputa- tion and a threefold higher mortality. Key Words: Fasciotomy, Compart- ment syndrome , Extremity, Revision, De- layed, Combat wounds

  5. Acute compartment syndrome of the thigh in a rugby player

    Science.gov (United States)

    Smith, Richard David James; Rust-March, Holly; Kluzek, Stefan

    2015-01-01

    In the absence of obvious trauma, diagnosis of acute compartment syndrome (ACS) of the thigh can easily be delayed, as disproportional pain is not always present. We present a case of ACS of the anterior right thigh compartment in a healthy, semiprofessional rugby player with normal coagulation, who sustained a seemingly innocuous blow during a rugby match. Following early surgical fasciotomy, he returned to his preinjury playing standards within 12 months. Our literature review suggests that high muscle mass, young, athletic males participating in a contact sport are mostly at risk of developing ACS of the thigh. PMID:26250368

  6. Isolating specific cell and tissue compartments from 3D images for quantitative regional distribution analysis using novel computer algorithms.

    Science.gov (United States)

    Fenrich, Keith K; Zhao, Ethan Y; Wei, Yuan; Garg, Anirudh; Rose, P Ken

    2014-04-15

    Isolating specific cellular and tissue compartments from 3D image stacks for quantitative distribution analysis is crucial for understanding cellular and tissue physiology under normal and pathological conditions. Current approaches are limited because they are designed to map the distributions of synapses onto the dendrites of stained neurons and/or require specific proprietary software packages for their implementation. To overcome these obstacles, we developed algorithms to Grow and Shrink Volumes of Interest (GSVI) to isolate specific cellular and tissue compartments from 3D image stacks for quantitative analysis and incorporated these algorithms into a user-friendly computer program that is open source and downloadable at no cost. The GSVI algorithm was used to isolate perivascular regions in the cortex of live animals and cell membrane regions of stained spinal motoneurons in histological sections. We tracked the real-time, intravital biodistribution of injected fluorophores with sub-cellular resolution from the vascular lumen to the perivascular and parenchymal space following a vascular microlesion, and mapped the precise distributions of membrane-associated KCC2 and gephyrin immunolabeling in dendritic and somatic regions of spinal motoneurons. Compared to existing approaches, the GSVI approach is specifically designed for isolating perivascular regions and membrane-associated regions for quantitative analysis, is user-friendly, and free. The GSVI algorithm is useful to quantify regional differences of stained biomarkers (e.g., cell membrane-associated channels) in relation to cell functions, and the effects of therapeutic strategies on the redistributions of biomolecules, drugs, and cells in diseased or injured tissues. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. A human polymorphism affects NEDD4L subcellular targeting by leading to two isoforms that contain or lack a C2 domain.

    Science.gov (United States)

    Garrone, Nicholas F; Blazer-Yost, Bonnie L; Weiss, Robert B; Lalouel, Jean-Marc; Rohrwasser, Andreas

    2009-04-13

    Ubiquitination serves multiple cellular functions, including proteasomal degradation and the control of stability, function, and intracellular localization of a wide variety of proteins. NEDD4L is a member of the HECT class of E3 ubiquitin ligases. A defining feature of NEDD4L protein isoforms is the presence or absence of an amino-terminal C2 domain, a class of subcellular, calcium-dependent targeting domains. We previously identified a common variant in human NEDD4L that generates isoforms that contain or lack a C2 domain. To address the potential functional significance of the NEDD4L common variant on NEDD4L subcellular localization, NEDD4L isoforms that either contained or lacked a C2 domain were tagged with enhanced green fluorescent protein, transfected into Xenopus laevis kidney epithelial cells, and imaged by performing confocal microscopy on live cells. We report that the presence or absence of this C2 domain exerts differential effects on the subcellular distribution of NEDD4L, the ability of C2 containing and lacking NEDD4L isoforms to mobilize in response to a calcium stimulus, and the intracellular transport of subunits of the NEDD4L substrate, ENaC. Furthermore, the ability of the C2-containing isoform to influence beta-ENaC mobilization from intracellular pools involves the NEDD4L active site for ubiquitination. We propose a model to account for the potential impact of this common genetic variant on protein function at the cellular level. NEDD4L isoforms that contain or lack a C2 domain target different intracellular locations. Additionally, whereas the C2-containing NEDD4L isoform is capable of shuttling between the plasma membrane and intracellular compartments in response to calcium stimulus the C2-lacking isoform can not. The C2-containing isoform differentially affects the mobilization of ENaC subunits from intracellular pools and this trafficking step requires NEDD4L ubiquitin ligase activity. This observation suggests a new mechanism for the

  8. A human polymorphism affects NEDD4L subcellular targeting by leading to two isoforms that contain or lack a C2 domain

    Directory of Open Access Journals (Sweden)

    Lalouel Jean-Marc

    2009-04-01

    Full Text Available Abstract Background Ubiquitination serves multiple cellular functions, including proteasomal degradation and the control of stability, function, and intracellular localization of a wide variety of proteins. NEDD4L is a member of the HECT class of E3 ubiquitin ligases. A defining feature of NEDD4L protein isoforms is the presence or absence of an amino-terminal C2 domain, a class of subcellular, calcium-dependent targeting domains. We previously identified a common variant in human NEDD4L that generates isoforms that contain or lack a C2 domain. Results To address the potential functional significance of the NEDD4L common variant on NEDD4L subcellular localization, NEDD4L isoforms that either contained or lacked a C2 domain were tagged with enhanced green fluorescent protein, transfected into Xenopus laevis kidney epithelial cells, and imaged by performing confocal microscopy on live cells. We report that the presence or absence of this C2 domain exerts differential effects on the subcellular distribution of NEDD4L, the ability of C2 containing and lacking NEDD4L isoforms to mobilize in response to a calcium stimulus, and the intracellular transport of subunits of the NEDD4L substrate, ENaC. Furthermore, the ability of the C2-containing isoform to influence β-ENaC mobilization from intracellular pools involves the NEDD4L active site for ubiquitination. We propose a model to account for the potential impact of this common genetic variant on protein function at the cellular level. Conclusion NEDD4L isoforms that contain or lack a C2 domain target different intracellular locations. Additionally, whereas the C2-containing NEDD4L isoform is capable of shuttling between the plasma membrane and intracellular compartments in response to calcium stimulus the C2-lacking isoform can not. The C2-containing isoform differentially affects the mobilization of ENaC subunits from intracellular pools and this trafficking step requires NEDD4L ubiquitin ligase

  9. Detrended cross-correlation coefficient: Application to predict apoptosis protein subcellular localization.

    Science.gov (United States)

    Liang, Yunyun; Liu, Sanyang; Zhang, Shengli

    2016-12-01

    Apoptosis, or programed cell death, plays a central role in the development and homeostasis of an organism. Obtaining information on subcellular location of apoptosis proteins is very helpful for understanding the apoptosis mechanism. The prediction of subcellular localization of an apoptosis protein is still a challenging task, and existing methods mainly based on protein primary sequences. In this paper, we introduce a new position-specific scoring matrix (PSSM)-based method by using detrended cross-correlation (DCCA) coefficient of non-overlapping windows. Then a 190-dimensional (190D) feature vector is constructed on two widely used datasets: CL317 and ZD98, and support vector machine is adopted as classifier. To evaluate the proposed method, objective and rigorous jackknife cross-validation tests are performed on the two datasets. The results show that our approach offers a novel and reliable PSSM-based tool for prediction of apoptosis protein subcellular localization. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Geary autocorrelation and DCCA coefficient: Application to predict apoptosis protein subcellular localization via PSSM

    Science.gov (United States)

    Liang, Yunyun; Liu, Sanyang; Zhang, Shengli

    2017-02-01

    Apoptosis is a fundamental process controlling normal tissue homeostasis by regulating a balance between cell proliferation and death. Predicting subcellular location of apoptosis proteins is very helpful for understanding its mechanism of programmed cell death. Prediction of apoptosis protein subcellular location is still a challenging and complicated task, and existing methods mainly based on protein primary sequences. In this paper, we propose a new position-specific scoring matrix (PSSM)-based model by using Geary autocorrelation function and detrended cross-correlation coefficient (DCCA coefficient). Then a 270-dimensional (270D) feature vector is constructed on three widely used datasets: ZD98, ZW225 and CL317, and support vector machine is adopted as classifier. The overall prediction accuracies are significantly improved by rigorous jackknife test. The results show that our model offers a reliable and effective PSSM-based tool for prediction of apoptosis protein subcellular localization.

  11. Use of correspondence discriminant analysis to predict the subcellular location of bacterial proteins.

    Science.gov (United States)

    Perrière, Guy; Thioulouse, Jean

    2003-02-01

    Correspondence discriminant analysis (CDA) is a multivariate statistical method derived from discriminant analysis which can be used on contingency tables. We have used CDA to separate Gram negative bacteria proteins according to their subcellular location. The high resolution of the discrimination obtained makes this method a good tool to predict subcellular location when this information is not known. The main advantage of this technique is its simplicity. Indeed, by computing two linear formulae on amino acid composition, it is possible to classify a protein into one of the three classes of subcellular location we have defined. The CDA itself can be computed with the ADE-4 software package that can be downloaded, as well as the data set used in this study, from the Pôle Bio-Informatique Lyonnais (PBIL) server at http://pbil.univ-lyon1.fr.

  12. Characterization of subcellular localization and stability of a splice variant of G alphai2

    Directory of Open Access Journals (Sweden)

    Wedegaertner Philip B

    2002-05-01

    Full Text Available Abstract Background Alternative mRNA splicing of αi2, a heterotrimeric G protein α subunit, has been shown to produce an additional protein, termed sαi2. In the sαi2 splice variant, 35 novel amino acids replace the normal C-terminal 24 amino acids of αi2. Whereas αi2 is found predominantly at cellular plasma membranes, sαi2 has been localized to intracellular Golgi membranes, and the unique 35 amino acids of sαi2 have been suggested to constitute a specific targeting signal. Results This paper proposes and examines an alternative hypothesis: disruption of the normal C-terminus of αi2 produces an unstable protein that fails to localize to plasma membranes. sαi2 is poorly expressed upon transfection of cultured cells; however, radiolabeling indicated that αi2 and sαi2 undergo myristoylation, a co-translational modification, equally well suggesting that protein stability rather than translation is affected. Indeed, pulse-chase analysis indicates that sαi2 is more rapidly degraded compared to αi2. Co-expression of βγ rescues PM localization and increases expression of sαi2. In addition, αi2A327S, a mutant previously shown to be unstable and defective in guanine-nucleotide binding, and αi2(1–331, in which the C-terminal 24 amino acids of αi2 are deleted, show a similar pattern of subcellular localization as sαi2 (i.e., intracellular membranes rather than plasma membranes. Finally, sαi2 displays a propensity to localize to potential aggresome-like structures. Conclusions Thus, instead of the novel C-terminus of sαi2 functioning as a specific Golgi targeting signal, the results presented here indicate that the disruption of the normal C-terminus of αi2 causes mislocalization and rapid degradation of sαi2.

  13. Characterization and subcellular targeting of GCaMP-type genetically-encoded calcium indicators.

    Directory of Open Access Journals (Sweden)

    Tianyi Mao

    2008-03-01

    Full Text Available Genetically-encoded calcium indicators (GECIs hold the promise of monitoring [Ca(2+] in selected populations of neurons and in specific cellular compartments. Relating GECI fluorescence to neuronal activity requires quantitative characterization. We have characterized a promising new genetically-encoded calcium indicator-GCaMP2-in mammalian pyramidal neurons. Fluorescence changes in response to single action potentials (17+/-10% DeltaF/F [mean+/-SD] could be detected in some, but not all, neurons. Trains of high-frequency action potentials yielded robust responses (302+/-50% for trains of 40 action potentials at 83 Hz. Responses were similar in acute brain slices from in utero electroporated mice, indicating that long-term expression did not interfere with GCaMP2 function. Membrane-targeted versions of GCaMP2 did not yield larger signals than their non-targeted counterparts. We further targeted GCaMP2 to dendritic spines to monitor Ca(2+ accumulations evoked by activation of synaptic NMDA receptors. We observed robust DeltaF/F responses (range: 37%-264% to single spine uncaging stimuli that were correlated with NMDA receptor currents measured through a somatic patch pipette. One major drawback of GCaMP2 was its low baseline fluorescence. Our results show that GCaMP2 is improved from the previous versions of GCaMP and may be suited to detect bursts of high-frequency action potentials and synaptic currents in vivo.

  14. 19 CFR 123.24 - Sealing of conveyances or compartments.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Sealing of conveyances or compartments. 123.24 Section 123.24 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY CUSTOMS RELATIONS WITH CANADA AND MEXICO Shipments in Transit Through Canada or...

  15. Surgical treatment for ~brain compartment syndrome' in children ...

    African Journals Online (AJOL)

    Objectives. Traumatic brain injury accounts for a high percentage of deaths in children. Raised intracranial pressure (ICP) due to brain swelling within the closed compartment of the skull leads to death or severe neurological disability if not effectively treated. We report our experience with 12 children who presented with ...

  16. Ward Round - Late Presentation of Acute Compartment Syndrome in ...

    African Journals Online (AJOL)

    following the course of ibuprofen mentioned. Twelve days after admission he started to complain of increasing pain and tightness in his left thigh. Sensation and motor function. Ward Round - Late Presentation of Acute. Compartment Syndrome in the Thigh. University of Malawi, College of Medicine, Department of Surgery,.

  17. latrogenic chronic compartment syndrome of leg due to ruptured ...

    African Journals Online (AJOL)

    A 45 year old male complaining of chronic pain and swelling of his left calf with features suggestive of chronic compartment syndrome following therapeutic aspiration of a popliteal cyst has been presented. It is a rare type of presentation which has not been reported to the knowledge of the authors. Review of literature and

  18. 9 CFR 354.241 - Cleaning of rooms and compartments.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Cleaning of rooms and compartments. 354.241 Section 354.241 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... Sanitary Conditions and Precautions Against Contamination of Products § 354.241 Cleaning of rooms and...

  19. Compartment syndrome and popliteal vascular injury complicating unicompartmental knee arthroplasty

    NARCIS (Netherlands)

    Kort, Nanne Pieter; Van Raay, Jos J. J. A. M.; van Horn, Jim R.

    Popliteal vascular injury and the compartment syndrome of the leg are rare but important complications of knee arthroplasties. Early diagnosis and treatment are of paramount importance in preventing the devastating complications of these conditions. To our knowledge, these complications have not

  20. Abdominal Compartment Syndrome in Acute Pancreatitis : A Systematic Review

    NARCIS (Netherlands)

    van Brunschot, Sandra; Schut, Anne Julia; Bouwense, Stefan A.; Besselink, Marc G.; Bakker, Olaf J.; Goor ,van Harry; Hofker, Hendrik; Gooszen, Hein G.; Boermeester, Marja A.; van Santvoort, Hjalmar C.

    Abdominal compartment syndrome (ACS) is a lethal complication of acute pancreatitis. We performed a systematic review to assess the treatment and outcome of these patients. A systematic literature search for cohorts of patients with acute pancreatitis and ACS was performed. The main outcomes were

  1. Abdominal compartment syndrome in acute pancreatitis: a systematic review

    NARCIS (Netherlands)

    van Brunschot, Sandra; Schut, Anne Julia; Bouwense, Stefan A.; Besselink, Marc G.; Bakker, Olaf J.; van Goor, Harry; Hofker, Sijbrand; Gooszen, Hein G.; Boermeester, Marja A.; van Santvoort, Hjalmar C.

    2014-01-01

    Abdominal compartment syndrome (ACS) is a lethal complication of acute pancreatitis. We performed a systematic review to assess the treatment and outcome of these patients.A systematic literature search for cohorts of patients with acute pancreatitis and ACS was performed. The main outcomes were

  2. "Compartment"-syndrom på underben, atypisk traumemekanisme

    DEFF Research Database (Denmark)

    Larsen, Michael H; Nielsen, Henrik Toft; Wester, Jens Ulrik

    2003-01-01

    Acute compartment syndrome (CS) is a limb threatening condition which warrants emergency treatment. We describe a case of a 37-year-old man with acute CS developed without major trauma. Early diagnosis and prompt treatment by decompressive fasciotomy is of vital importance in order to preserve limb...

  3. The abdominal compartment syndrome : A complication with many faces

    NARCIS (Netherlands)

    Berger, P.; Nijsten, MWN; Paling, JC; Zwaveling, JH

    Background: Lately renewed attention has been given to the abdominal compartment syndrome. Despite of this there still remain a lot of controversies with regard to the pathophysiological mechanisms underlying this syndrome and the therapeutic options. Methods: Two cases of patients with this

  4. Acute compartment syndrome of the thigh without associated ...

    African Journals Online (AJOL)

    Acute compartment syndrome of the thigh is a rare complication of trauma to the thigh. It occurs less commonly than in other sites such as the leg and forearm. Because of its rarity, it is often not suspected and its diagnosis is frequently delayed with disastrous consequences. We report a patient who sustained blunt trauma to ...

  5. 14 CFR 125.167 - Extinguishing agent container compartment temperature.

    Science.gov (United States)

    2010-01-01

    ... temperature. 125.167 Section 125.167 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Requirements § 125.167 Extinguishing agent container compartment temperature. Precautions must be taken to ensure that the extinguishing agent containers are installed in places where reasonable temperatures can...

  6. 14 CFR 121.269 - Extinguishing agent container compartment temperature.

    Science.gov (United States)

    2010-01-01

    ... temperature. 121.269 Section 121.269 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF....269 Extinguishing agent container compartment temperature. Precautions must be taken to insure that the extinguishing agent containers are installed in places where reasonable temperatures can be...

  7. 46 CFR 169.625 - Compartments containing diesel machinery.

    Science.gov (United States)

    2010-10-01

    ...-cooled propulsion and auxiliary engines installed below deck must be fitted with air intake ducts or... arrangement including air intakes, exhaust stack, method of attachment of ventilation ducts to the engine... mechanical supply and exhaust ventilation. One duct must extend to a point near the bottom of the compartment...

  8. 14 CFR 23.853 - Passenger and crew compartment interiors.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Passenger and crew compartment interiors. 23.853 Section 23.853 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... instruments in a common housing, seatbelts, shoulder harnesses, and cargo and baggage tiedown equipment...

  9. A wolf in wolf's clothing the abdominal compartment syndrome

    African Journals Online (AJOL)

    A wolf in wolf's clothing the abdominal compartment syndrome. R. Burrows, J. Edington, J. V. Robbs. Four patients are described in whom massive abdominal distension after laparotomy led to ... abdominal surgery or trauma may not be a prerequisite for ... high peak airway pressure and high CVP, although urine output and ...

  10. The abdominal compartment syndrome (ACS) in general surgery.

    Science.gov (United States)

    Bodnár, Zsolt; Sipka, Sándor; Hajdu, Zoltán

    2008-01-01

    The abdominal compartment syndrome is a life threatening clinical entity which can develop within the first 12 hours of intensive care unit admission in high-risk surgical patients. The aim of this paper is to show the definitions, ethiology, pathophysiology, diagnosis and treatment of this serious, not only surgical problem. The mortality due to the abdominal compartment syndrome is extremely high (38-71%). It can be defined as adverse physiologic consequences that occur as a result of an acute increase in the intraabdominal pressure. The most common causes are retroperitoneal haemorrhage, visceral oedema, pancreatitis, bowel obstruction, tense ascites, peritonitis, tumor. The mostly affected systems are cardiovascular, pulmonary, renal, central nervous systems and splanchnic organs. The gold standard diagnostic method is the continuous intra-abdominal pressure monitoring. The treatment consists of adequate fluid resuscitation and surgical decompression. We show three typical short case reports treated by the above mentioned theories. Intraabdominal hypertension and abdominal compartment syndrome are frequent clinical findings among acute general surgical patients. Patients with comparable demographics and acute severity of illness are more likely to die if intraabdominal hypertension or abdominal compartment syndrome is present. We conclude that the early recognition and surgical decompression is urgent.

  11. The compartmented alginate fibres optimisation for bitumen rejuvenator encapsulation

    Directory of Open Access Journals (Sweden)

    Amir Tabaković

    2017-08-01

    Full Text Available This article presents development of a novel self-healing technology for asphalt pavements, where asphalt binder rejuvenator is encapsulated within the compartmented alginate fibres. The key objective of the study was to optimise the compartmented alginate fibre design, i.e., maximising amount of rejuvenator encapsulated within the fibre. The results demonstrate that optimum rejuvenator content in the alginate fibre is of 70:30 rejuvenator/alginate ratio. The fibres are of sufficient thermal and mechanical strength to survive harsh asphalt mixing and compaction processes. Furthermore, results illustrate that zeer open asfalt beton (ZOAB asphalt mix containing 5% of 70:30 rejuvenator/alginate ratio compartmented alginate fibres has higher strength, stiffness and better healing properties in comparison to the control asphalt mix, i.e., mix without fibres, and mix containing fibres with lower rejuvenator content. These results show that compartmented alginate fibres encapsulating bitumen rejuvenator present a promising new approach for the development of self-healing asphalt pavement systems.

  12. Chronic exertional compartment syndrome in the forearm of a rower ...

    African Journals Online (AJOL)

    This case report describes chronic exertional compartment syndrome in the forearm of a professional rower. We consider this to be a rare anatomical location for this type of syndrome. Morever, not much is known about its clinical presentation and the subsequent optimal medical management thereof.

  13. 14 CFR 25.773 - Pilot compartment view.

    Science.gov (United States)

    2010-01-01

    ...) Internal windshield and window fogging. The airplane must have a means to prevent fogging of the internal... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Personnel and Cargo Accommodations... limitations of the airplane, including taxiing takeoff, approach, and landing. (2) Each pilot compartment must...

  14. Organic nano-compartments as biomimetic reactors, and protocells

    DEFF Research Database (Denmark)

    Monnard, Pierre-Alain; Ziock, Hans-Joachim; DeClue, Michael S.

    2008-01-01

    In recent years, nanoscale self-assembled structures have attracted ever increasing attention because of their potential to act as molecular templates for the synthesis of novel materials, delivery vehicles for therapeutic agents, and compartments defined at the molecular level that provide envir...

  15. Gluteal Compartment Syndrome following an Iliac Bone Marrow Aspiration

    Directory of Open Access Journals (Sweden)

    Edmundo Berumen-Nafarrate

    2013-01-01

    Full Text Available The compartment syndrome is a condition characterized by a raised hydraulic pressure within a closed and non expandable anatomical space. It leads to a vascular insufficiency that becomes critical once the vascular flow cannot return the fluids back to the venous system. This causes a potential irreversible damage of the contents of the compartment, especially within the muscle tissues. Gluteal compartment syndrome (GCS secondary to hematomas is seldom reported. Here we present a case of a 51-year-old patient with history of a non-Hodgkin lymphoma who underwent a bone marrow aspiration from the posterior iliac crest that had excessive bleeding at the puncture zone. The patient complained of increasing pain, tenderness, and buttock swelling. Intraoperative pressure validation of the gluteal compartment was performed, and a GCS was diagnosed. The patient was treated with a gluteal region fasciotomy. The patient recovered from pain and swelling and was discharged shortly after from the hospital. We believe clotting and hematologic disorders are a primary risk factor in patients who require bone marrow aspirations or biopsies. It is important to improve awareness of GCS in order to achieve early diagnosis, avoid complications, and have a better prognosis.

  16. Awolf in wolf's clothing the abdominal compartment syndrome ...

    African Journals Online (AJOL)

    All cases were associated with massive fluid resuscitation and operative findings were a grossly oedematous bowel with free fluid under pressure in the abdomen. These findings are consistent with the diagnosis of intra-abdominal compartment syndrome. In 1 case trauma was remote from the abdomen indicating that ...

  17. High resolution imaging of temporal and spatial changes of subcellular ascorbate, glutathione and H₂O₂ distribution during Botrytis cinerea infection in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Uwe K Simon

    Full Text Available In order to study the mechanisms behind the infection process of the necrotrophic fungus Botrytis cinerea, the subcellular distribution of hydrogen peroxide (H₂O₂ was monitored over a time frame of 96 h post inoculation (hpi in Arabidopsis thaliana Col-0 leaves at the inoculation site (IS and the area around the IS which was defined as area adjacent to the inoculation site (AIS. H₂O₂ accumulation was correlated with changes in the compartment-specific distribution of ascorbate and glutathione and chloroplast fine structure. This study revealed that the severe breakdown of the antioxidative system, indicated by a drop in ascorbate and glutathione contents at the IS at later stages of infection correlated with an accumulation of H₂O₂ in chloroplasts, mitochondria, cell walls, nuclei and the cytosol which resulted in the development of chlorosis and cell death, eventually visible as tissue necrosis. A steady increase of glutathione contents in most cell compartments within infected tissues (up to 600% in chloroplasts at 96 hpi correlated with an accumulation of H₂O₂ in chloroplasts, mitochondria and cell walls at the AIS indicating that high glutathione levels could not prevent the accumulation of reactive oxygen species (ROS which resulted in chlorosis. Summing up, this study reveals the intracellular sequence of events during Botrytis cinerea infection and shows that the breakdown of the antioxidative system correlated with the accumulation of H₂O₂ in the host cells. This resulted in the degeneration of the leaf indicated by severe changes in the number and ultrastructure of chloroplasts (e.g. decrease of chloroplast number, decrease of starch and thylakoid contents, increase of plastoglobuli size, chlorosis and necrosis of the leaves.

  18. High Resolution Imaging of Temporal and Spatial Changes of Subcellular Ascorbate, Glutathione and H2O2 Distribution during Botrytis cinerea Infection in Arabidopsis

    Science.gov (United States)

    Simon, Uwe K.; Polanschütz, Lisa M.; Koffler, Barbara E.; Zechmann, Bernd

    2013-01-01

    In order to study the mechanisms behind the infection process of the necrotrophic fungus Botrytis cinerea, the subcellular distribution of hydrogen peroxide (H2O2) was monitored over a time frame of 96 h post inoculation (hpi) in Arabidopsis thaliana Col-0 leaves at the inoculation site (IS) and the area around the IS which was defined as area adjacent to the inoculation site (AIS). H2O2 accumulation was correlated with changes in the compartment-specific distribution of ascorbate and glutathione and chloroplast fine structure. This study revealed that the severe breakdown of the antioxidative system, indicated by a drop in ascorbate and glutathione contents at the IS at later stages of infection correlated with an accumulation of H2O2 in chloroplasts, mitochondria, cell walls, nuclei and the cytosol which resulted in the development of chlorosis and cell death, eventually visible as tissue necrosis. A steady increase of glutathione contents in most cell compartments within infected tissues (up to 600% in chloroplasts at 96 hpi) correlated with an accumulation of H2O2 in chloroplasts, mitochondria and cell walls at the AIS indicating that high glutathione levels could not prevent the accumulation of reactive oxygen species (ROS) which resulted in chlorosis. Summing up, this study reveals the intracellular sequence of events during Botrytis cinerea infection and shows that the breakdown of the antioxidative system correlated with the accumulation of H2O2 in the host cells. This resulted in the degeneration of the leaf indicated by severe changes in the number and ultrastructure of chloroplasts (e.g. decrease of chloroplast number, decrease of starch and thylakoid contents, increase of plastoglobuli size), chlorosis and necrosis of the leaves. PMID:23755284

  19. Compartment syndrome of the thigh: a systematic review.

    Science.gov (United States)

    Ojike, Nwakile I; Roberts, Craig S; Giannoudis, Peter V

    2010-02-01

    Thigh compartment syndrome is a surgical emergency with risk of high morbidity and mortality rates. The purpose of this study was to review the available evidence regarding the causes of thigh compartment syndrome, techniques of fasciotomy (specifically, one versus two incisions), methods of wound closure, and complications. This institutional review board-exempt study was performed at a level-one trauma centre. PubMed and Medline OVID databases in the English language were searched for case series of two or more cases of compartment syndrome of the thigh. Cases were reviewed and analysed for causes of thigh compartment syndrome, number of fasciotomy incisions, methods of wound closure, and complications. A total of 9 papers met our criteria. All were retrospective case studies comprising a total of 89 patients. The most common cause was blunt trauma (90%). Motor vehicle accidents accounted for 36% of cases whilst motorcycle accidents were involved in 9%. Associated injuries included femur fractures in 48%, other limb fractures, renal, cardiovascular and head insults. Eighty-six percent of fasciotomies were performed through a single incision. Fifty-nine percent of fasciotomy wounds were closed by delayed primary closure, 26% had split-thickness skin grafts, and 15% had primary wound closure. Neurological deficits were the most common complications. There are limited data on thigh compartment syndrome with respect to cause, use of one versus two incisions for fasciotomy, methods of wound closure, and complication rates. Prospective studies are required to better define these variables in order to optimise the management of this problem. Copyright 2009 Elsevier Ltd. All rights reserved.

  20. Acute lumbar paraspinal compartment syndrome: a systematic review.

    Science.gov (United States)

    Alexander, William; Low, Nelson; Pratt, George

    2018-01-08

    While still a rare entity, acute lumbar paraspinal compartment syndrome has an increasing incidence. Similar to other compartment syndromes, acute lumbar paraspinal compartment syndrome is defined by raised pressure within a closed fibro-osseous space, limiting tissue perfusion within that space. The resultant tissue ischaemia presents as acute pain, and if left untreated, it may result in permanent tissue damage. A literature search of 'paraspinal compartment syndrome' revealed 21 articles. The details from a case encountered by the authors are also included. A common data set was extracted, focusing on demographics, aetiology, clinical features, management and outcomes. There are 23 reported cases of acute compartment syndrome. These are typically caused by weight-lifting exercises, but may also result from other exercises, direct trauma or non-spinal surgery. Pain, tenderness and paraspinal paraesthesia are key clinical findings. Serum creatine kinase, magnetic resonance imaging and intracompartment pressure measurement confirm the diagnosis. Half of the reported cases have been managed with surgical fasciotomy, and these patients have all had good outcomes relative to those managed with conservative measures with or without hyperbaric oxygen therapy. These good outcomes were despite significant delays to operative intervention. The diagnostic uncertainty and subsequent delay to fasciotomy result from the rarity of this disease entity, and a high level of suspicion is recommended in the appropriate setting. This is particularly true in light of the current popularity of extreme weight lifting in non-professional athletes. Operative intervention is strongly recommended in all cases based on the available evidence. © 2018 Royal Australasian College of Surgeons.

  1. Lift-and-fill face lift: integrating the fat compartments.

    Science.gov (United States)

    Rohrich, Rod J; Ghavami, Ashkan; Constantine, Fadi C; Unger, Jacob; Mojallal, Ali

    2014-06-01

    Recent discovery of the numerous fat compartments of the face has improved our ability to more precisely restore facial volume while rejuvenating it through differential superficial musculoaponeurotic system treatment. Incorporation of selective fat compartment volume restoration along with superficial musculoaponeurotic system manipulation allows for improved control in recontouring while addressing one of the key problems in facial aging, namely, volume deflation. This theory was evaluated by assessing the contour changes from simultaneous face "lifting" and "filling" through fat compartment-guided facial fat transfer. A review of 100 face-lift patients was performed. All patients had an individualized component face lift with fat grafting to the nasolabial fold, deep malar, and high/lateral malar fat compartment locations. Photographic analysis using a computer program was conducted on oblique facial views preoperatively and postoperatively, to obtain the most projected malar contour point. Two independent observers visually evaluated the malar prominence and nasolabial fold improvements based on standardized photographs. Nasolabial fold improved by at least one grade in 81 percent and by over one grade in 11 percent. Malar prominence average projection increase was 13.47 percent and the average amount of lift was 12.24 percent. The malar prominence score improved by at least one grade in 62 percent of the patients postoperatively, and 9 percent had a greater than one grade improvement. Twenty-eight percent of the patients had a convex malar prominence postoperatively compared with 6 percent preoperatively. Malar prominence improved by at least one grade in 63 percent and by over one grade in 10 percent. The lift-and-fill face lift merges two key concepts in facial rejuvenation: (1) effective tissue manipulation by means of lifting and tightening in differential vectors according to original facial asymmetry and shape; and (2) selective fat compartment filling

  2. Multimodal delivery of irinotecan from microparticles with two distinct compartments.

    Science.gov (United States)

    Rahmani, Sahar; Park, Tae-Hong; Dishman, Acacia Frances; Lahann, Joerg

    2013-11-28

    In the last several decades, research in the field of drug delivery has been challenged with the fabrication of carrier systems engineered to deliver therapeutics to the target site with sustained and controlled release kinetics. Herein, we report the fabrication of microparticles composed of two distinct compartments: i) one compartment containing a pH responsive polymer, acetal-modified dextran, and PLGA (polylactide-co-glycolide), and ii) one compartment composed entirely of PLGA. We demonstrate the complete release of dextran from the microparticles during a 10-hour period in an acidic pH environment and the complete degradation of one compartment in less than 24h. This is in congruence with the stability of the same microparticles in neutral pH over the 24-hour period. Such microparticles can be used as pH responsive carrier systems for drug delivery applications where their cargo will only be released when the optimum pH window is reached. The feasibility of the microparticle system for such an application was confirmed by encapsulating a cancer therapeutic, irinotecan, in the compartment containing the acetal-modified dextran polymer and the pH dependent release over a 5-day period was studied. It was found that upon pH change to an acidic environment, over 50% of the drug was first released at a rapid rate for 10h, similar to that observed for the dextran release, before continuing at a more controlled rate for 4 days. As such, these microparticles can play an important role in the fabrication of novel drug delivery systems due to the selective, controlled, and pH responsive release of their encapsulated therapeutics. © 2013.

  3. Quantitative T1-mapping detects cloudy-enhancing tumor compartments predicting outcome of patients with glioblastoma.

    Science.gov (United States)

    Müller, Andreas; Jurcoane, Alina; Kebir, Sied; Ditter, Philip; Schrader, Felix; Herrlinger, Ulrich; Tzaridis, Theophilos; Mädler, Burkhard; Schild, Hans H; Glas, Martin; Hattingen, Elke

    2017-01-01

    Contrast enhancement of glioblastomas (GBM) is caused by the decrease in relaxation time, T1. Here, we demonstrate that the quantitative measurement of T1 (qT1) discovers a subtle enhancement in GBM patients that is invisible in standard MRI. We assessed the volume change of this "cloudy" enhancement during radio-chemotherapy and its impact on patients' progression-free survival (PFS). We enrolled 18 GBM patients in this observational, prospective cohort study and measured 3T-MRI pre- and post contrast agent with standard T1-weighted (T1w) and with sequences to quantify T1 before radiation, and at 6-week intervals during radio-chemotherapy. We measured contrast enhancement by subtracting pre from post contrast contrast images, yielding relative signal increase ∆T1w and relative T1 shortening ∆qT1. On ∆qT1, we identified a solid and a cloudy-enhancing compartment and evaluated the impact of their therapy-related volume change upon PFS. In ∆qT1 maps cloudy-enhancing compartments were found in all but two patients at baseline and in all patients during therapy. The qT1 decrease in the cloudy-enhancing compartment post contrast was 21.64% versus 1.96% in the contralateral control tissue (P mapping and may represent tumor infiltration. Its early volume decrease predicts a longer PFS in GBM patients during standard radio-chemotherapy. © 2016 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  4. A functional dissection of PTEN N-terminus : Implications in PTEN subcellular targeting and tumor suppressor activity

    NARCIS (Netherlands)

    Gil, Anabel; Rodríguez-Escudero, Isabel; Stumpf, Miriam; Molina, María; Cid, Víctor J.; Pulido, Rafael

    2015-01-01

    Spatial regulation of the tumor suppressor PTEN is exerted through alternative plasma membrane, cytoplasmic, and nuclear subcellular locations. The N-terminal region of PTEN is important for the control of PTEN subcellular localization and function. It contains both an active nuclear localization

  5. Subcellular location of the enzymes of purine breakdown in the yeast Candida famata grown on uric acid

    NARCIS (Netherlands)

    Large, Peter J.; Waterham, Hans R.; Veenhuis, Marten

    1990-01-01

    The subcellular location of the enzymes of purine breakdown in the yeast Candida famata, which grows on uric acid as sole carbon and nitrogen source, has been examined by subcellular fractionation methods. Uricase was confirmed as being peroxisomal, but the other three enzymes, allantoinase,

  6. The tetraspan protein CD82 is a resident of MHC class II compartments where it associates with HLA-DR, -DM, and -DO molecules.

    Science.gov (United States)

    Hammond, C; Denzin, L K; Pan, M; Griffith, J M; Geuze, H J; Cresswell, P

    1998-10-01

    In specialized APCs, MHC class II molecules are synthesized in the endoplasmic reticulum and transported through the Golgi apparatus to organelles of the endocytic pathway collectively called MHC class II compartments (MIICs). There, the class II-associated invariant chain is degraded, and peptides derived from internalized Ag bind to empty class II in a reaction that is facilitated by the class II-like molecule HLA-DM. An mAb raised to highly purified, immunoisolated MIICs from human B lymphoblastoid cells recognized CD82, a member of the tetraspan family of integral membrane proteins. Subcellular fractionation, immunofluorescence microscopy, and immunoelectron microscopy showed that CD82 is highly enriched in MIICs, particularly in their internal membranes. Coprecipitation analysis showed that CD82 associates in MIICs with class II, DM, and HLA-DO (an inhibitor of peptide loading that binds DM). Similar experiments showed CD63, another tetraspan protein found in MIICs, also associates with these molecules in the compartment and that CD82 and CD63 associate with each other. Preclearing experiments demonstrated that both CD82 and CD63 form complexes with DM-associated class II and DM-associated DO. The ability of CD82 and CD63 to form complexes with class II, DM, and DO in MIICs suggests that the tetraspan proteins may play an important role in the late stages of MHC class II maturation.

  7. Neural Membrane Signaling Platforms

    Directory of Open Access Journals (Sweden)

    Ron Wallace

    2010-06-01

    Full Text Available Throughout much of the history of biology, the cell membrane was functionally defined as a semi-permeable barrier separating aqueous compartments, and an anchoring site for proteins. Little attention was devoted to its possible regulatory role in intracellular molecular processes and neuron electrical signaling. This article reviews the history of membrane studies and the current state of the art. Emphasis is placed on natural and artificial membrane studies of electric field effects on molecular organization, especially as these may relate to impulse propagation in neurons. Implications of these studies for new designs in artificial intelligence are briefly examined.

  8. Neural membrane signaling platforms.

    Science.gov (United States)

    Wallace, Ron

    2010-06-10

    Throughout much of the history of biology, the cell membrane was functionally defined as a semi-permeable barrier separating aqueous compartments, and an anchoring site for proteins. Little attention was devoted to its possible regulatory role in intracellular molecular processes and neuron electrical signaling. This article reviews the history of membrane studies and the current state of the art. Emphasis is placed on natural and artificial membrane studies of electric field effects on molecular organization, especially as these may relate to impulse propagation in neurons. Implications of these studies for new designs in artificial intelligence are briefly examined.

  9. Sub-cellular localisation studies may spuriously detect the Yes-associated protein, YAP, in nucleoli leading to potentially invalid conclusions of its function.

    Directory of Open Access Journals (Sweden)

    Megan L Finch

    Full Text Available The Yes-associated protein (YAP is a potent transcriptional co-activator that functions as a nuclear effector of the Hippo signaling pathway. YAP is oncogenic and its activity is linked to its cellular abundance and nuclear localisation. Activation of the Hippo pathway restricts YAP nuclear entry via its phosphorylation by Lats kinases and consequent cytoplasmic retention bound to 14-3-3 proteins. We examined YAP expression in liver progenitor cells (LPCs and surprisingly found that transformed LPCs did not show an increase in YAP abundance compared to the non-transformed LPCs from which they were derived. We then sought to ascertain whether nuclear YAP was more abundant in transformed LPCs. We used an antibody that we confirmed was specific for YAP by immunoblotting to determine YAP's sub-cellular localisation by immunofluorescence. This antibody showed diffuse staining for YAP within the cytosol and nuclei, but, noticeably, it showed intense staining of the nucleoli of LPCs. This staining was non-specific, as shRNA treatment of cells abolished YAP expression to undetectable levels by Western blot yet the nucleolar staining remained. Similar spurious YAP nucleolar staining was also seen in mouse embryonic fibroblasts and mouse liver tissue, indicating that this antibody is unsuitable for immunological applications to determine YAP sub-cellular localisation in mouse cells or tissues. Interestingly nucleolar staining was not evident in D645 cells suggesting the antibody may be suitable for use in human cells. Given the large body of published work on YAP in recent years, many of which utilise this antibody, this study raises concerns regarding its use for determining sub-cellular localisation. From a broader perspective, it serves as a timely reminder of the need to perform appropriate controls to ensure the validity of published data.

  10. Components of the hematopoietic compartments in tumor stroma and tumor-bearing mice.

    Directory of Open Access Journals (Sweden)

    HoangDinh Huynh

    2011-03-01

    Full Text Available Solid tumors are composed of cancerous cells and non-cancerous stroma. A better understanding of the tumor stroma could lead to new therapeutic applications. However, the exact compositions and functions of the tumor stroma are still largely unknown. Here, using a Lewis lung carcinoma implantation mouse model, we examined the hematopoietic compartments in tumor stroma and tumor-bearing mice. Different lineages of differentiated hematopoietic cells existed in tumor stroma with the percentage of myeloid cells increasing and the percentage of lymphoid and erythroid cells decreasing over time. Using bone marrow reconstitution analysis, we showed that the tumor stroma also contained functional hematopoietic stem cells. All hematopoietic cells in the tumor stroma originated from bone marrow. In the bone marrow and peripheral blood of tumor-bearing mice, myeloid populations increased and lymphoid and erythroid populations decreased and numbers of hematopoietic stem cells markedly increased with time. To investigate the function of hematopoietic cells in tumor stroma, we co-implanted various types of hematopoietic cells with cancer cells. We found that total hematopoietic cells in the tumor stroma promoted tumor development. Furthermore, the growth of the primary implanted Lewis lung carcinomas and their metastasis were significantly decreased in mice reconstituted with IGF type I receptor-deficient hematopoietic stem cells, indicating that IGF signaling in the hematopoietic tumor stroma supports tumor outgrowth. These results reveal that hematopoietic cells in the tumor stroma regulate tumor development and that tumor progression significantly alters the host hematopoietic compartment.

  11. Characterization, sub-cellular localization and expression profiling of the isoprenylcysteine methylesterase gene family in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Ma Wujun

    2010-09-01

    Full Text Available Abstract Background Isoprenylcysteine methylesterases (ICME demethylate prenylated protein in eukaryotic cell. Until now, knowledge about their molecular information, localization and expression pattern is largely unavailable in plant species. One ICME in Arabidopsis, encoded by At5g15860, has been identified recently. Over-expression of At5g15860 caused an ABA hypersensitive phenotype in transgenic Arabidopsis plants, indicating that it functions as a positive regulator of ABA signaling. Moreover, ABA induced the expression of this gene in Arabidopsis seedlings. The current study extends these findings by examining the sub-cellular localization, expression profiling, and physiological functions of ICME and two other ICME-like proteins, ICME-LIKE1 and ICME-LIKE2, which were encoded by two related genes At1g26120 and At3g02410, respectively. Results Bioinformatics investigations showed that the ICME and other two ICME-like homologs comprise a small subfamily of carboxylesterase (EC 3.1.1.1 in Arabidopsis. Sub-cellular localization of GFP tagged ICME and its homologs showed that the ICME and ICME-like proteins are intramembrane proteins predominantly localizing in the endoplasmic reticulum (ER and Golgi apparatus. Semi-quantitative and real-time quantitative PCR revealed that the ICME and ICME-like genes are expressed in all examined tissues, including roots, rosette leaves, cauline leaves, stems, flowers, and siliques, with differential expression levels. Within the gene family, the base transcript abundance of ICME-LIKE2 gene is very low with higher expression in reproductive organs (flowers and siliques. Time-course analysis uncovered that both ICME and ICME-like genes are up-regulated by mannitol, NaCl and ABA treatment, with ICME showing the highest level of up-regulation by these treatments. Heat stress resulted in up-regulation of the ICME gene significantly but down-regulation of the ICME-LIKE1 and ICME-LIKE2 genes. Cold and dehydration

  12. Subcellular Localization of Galloylated Catechins in Tea Plants (Camellia sinensis (L. O. Kuntze Assessed via Immunohistochemistry

    Directory of Open Access Journals (Sweden)

    Huanhuan eXu

    2016-05-01

    Full Text Available Galloylated catechins, as the main secondary metabolites in the tea plant, including (--epigallocatechin-3-gallate and (--epicatechin-3-gallate, comprise approximately three-quarters of all the tea plant catechins and have stronger effects than non-galloylated catechins, both on the product quality in tea processing and the pharmacological efficacy to human beings. The subcellular localization of galloylated catechins has been the primary focus of studies that assess biosynthesis and physiological functions. Classical histochemical localization staining reagents can not specifically detect galloylated catechins; thus, their subcellular localization remains controversial. In the present study, we generated a monoclonal antibody (mAb against galloylated catechins, which can be used for the subcellular localization of galloylated catechins in the tea plant by immunohistochemistry. Direct ELISA and ForteBio Octet Red 96 System assay indicated the mAb could recognize the galloylated catechins with high specificities and affinities. In addition, tea bud was ascertained as the optimal tissue for freezing microtomic sections for immunohistochemistry. What’s more, the high quality mAbs which exhibited excellent binding capability to galloylated catechins were utilised for the visualization of them via immunohistochemistry. Our findings demonstrated that vacuoles were the primary sites of localization of galloylated catechins at the subcellular level.

  13. Halides tuning the subcellular-targeting in two-photon emissive complexes via different uptake mechanisms.

    Science.gov (United States)

    Tian, Xiaohe; Zhu, Yingzhong; Zhang, Qiong; Zhang, Ruilong; Wu, Jieying; Tian, Yupeng

    2017-07-11

    We reported a simple and universal strategy by tuning halides (Cl, Br and I) in terpyridine-Zn(ii) complexes to achieve different subcellular organelle targeting (nucleolus, nucleus and intracellular membrane systems, respectively) via different cellular uptake mechanisms, resulting from halide triggering different polymorphs of these complexes.

  14. Multivalency Effect of TAT-Peptide-Functionalized Nanoparticle in Cellular Endocytosis and Subcellular Trafficking.

    Science.gov (United States)

    Dalal, Chumki; Jana, Nikhil R

    2017-04-13

    Although trans-activating transcription (TAT) peptide-functionalized nanoparticle/polymer/liposome is widely used for cellular transfection applications, the multivalency (number of attached peptide per particle) effect on cell uptake mechanism and subcellular targeting performance is largely unexplored. Here we show that multivalency of nanoparticle controls the cellular interaction, cellular entry/exit mechanism, and subcellular targeting performance. We have synthesized TAT-peptide functionalized quantum dot (QD) of 30-35 nm hydrodynamic diameter with varied multivalency from 10 to 75 (e.g., QD(TAT)10, QD(TAT)20, QD(TAT)40, QD(TAT)75) and studied the role of multivalency in endocytosis and subcellular trafficking. We found that both low and high multivalent nanoparticles enter into cell predominantly via lipid-raft mediated endocytosis but the higher multivalency of 40 and 75 induces vesicular trapping followed by exocytosis within 12 h. In contrast, lower multivalency of 10 and 20 offers efficient trafficking toward perinuclear region and Golgi apparatus. This work shows the functional role of nanoparticle multivalency in cellular uptake mechanism and importance of lower multivalency for efficient subcellular targeting.

  15. Parasites modify sub-cellular partitioning of metals in the gut of fish

    NARCIS (Netherlands)

    Oyoo-Okoth, E.; Admiraal, W.; Osano, O.; Kraak, M.H.S.; Gichuki, J.; Ogwai, C.

    2012-01-01

    Infestation of fish by parasites may influence metal accumulation patterns in the host. However, the subcellular mechanisms of these processes have rarely been studied. Therefore, this study determined how a cyprinid fish (Rastrineobola argentea) partitioned four metals (Cd, Cr, Zn and Cu) in the

  16. Exploring Nanostructure Arrays for Single-Cell and Subcellular Manipulation and Detection

    DEFF Research Database (Denmark)

    Buch-Månson, Nina

    these, arrays of vertical nanostructures (NSs) with submicron diametersand microscale lengths are particularly promising and are currently being established as bothhighly sensitive protein arrays and as platforms for manipulations and investigations at thesingle-cell or even subcellular level.To date...

  17. PSI: a comprehensive and integrative approach for accurate plant subcellular localization prediction.

    Directory of Open Access Journals (Sweden)

    Lili Liu

    Full Text Available Predicting the subcellular localization of proteins conquers the major drawbacks of high-throughput localization experiments that are costly and time-consuming. However, current subcellular localization predictors are limited in scope and accuracy. In particular, most predictors perform well on certain locations or with certain data sets while poorly on others. Here, we present PSI, a novel high accuracy web server for plant subcellular localization prediction. PSI derives the wisdom of multiple specialized predictors via a joint-approach of group decision making strategy and machine learning methods to give an integrated best result. The overall accuracy obtained (up to 93.4% was higher than best individual (CELLO by ~10.7%. The precision of each predicable subcellular location (more than 80% far exceeds that of the individual predictors. It can also deal with multi-localization proteins. PSI is expected to be a powerful tool in protein location engineering as well as in plant sciences, while the strategy employed could be applied to other integrative problems. A user-friendly web server, PSI, has been developed for free access at http://bis.zju.edu.cn/psi/.

  18. Subcellular localization and mechanism of secretion of vascular endothelial growth factor in human skeletal muscle

    DEFF Research Database (Denmark)

    Høier, Birgitte; Prats Gavalda, Clara; Qvortrup, Klaus

    2013-01-01

    The subcellular distribution and secretion of vascular endothelial growth factor (VEGF) was examined in skeletal muscle of healthy humans. Skeletal muscle biopsies were obtained from m.v. lateralis before and after a 2 h bout of cycling exercise. VEGF localization was conducted on preparations...

  19. Development of a Charged Particle Microbeam for Targeted and Single Particle Subcellular Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Yanch, Jacquelyn C.

    2004-03-12

    The development of a charged particle microbeam for single particle, subcellular irradiations at the Massachusetts Institute of Technology Laboratory for Accelerator Beam Applications (MIT LABA) was initiated under this NEER aeard. The Microbeam apparatus makes use of a pre-existing electrostatic accelerator with a horizontal beam tube.

  20. Subcellular Localization of Cadmium in Chlorella vulgaris Beijerinck Strain Bt-09

    Directory of Open Access Journals (Sweden)

    P.B. Lintongan

    2004-06-01

    Full Text Available Growth response curves of Chlorella vulgaris Beijerinck strain Bt-09 to sublethal concentrations of cadmium were evaluated. The growth responses of this microalgal isolate was determined through analysis of chlorophyll a levels. Cadmium was effectively taken up by the cells as determined by Flame Atomic Absorption Spectrophotometry (F-AAS. Subcellular fractionation was undertaken to locate sites that accumulate cadmium.

  1. DeepLoc: prediction of protein subcellular localization using deep learning.

    Science.gov (United States)

    Almagro Armenteros, José Juan; Sønderby, Casper Kaae; Sønderby, Søren Kaae; Nielsen, Henrik; Winther, Ole

    2017-11-01

    The prediction of eukaryotic protein subcellular localization is a well-studied topic in bioinformatics due to its relevance in proteomics research. Many machine learning methods have been successfully applied in this task, but in most of them, predictions rely on annotation of homologues from knowledge databases. For novel proteins where no annotated homologues exist, and for predicting the effects of sequence variants, it is desirable to have methods for predicting protein properties from sequence information only. Here, we present a prediction algorithm using deep neural networks to predict protein subcellular localization relying only on sequence information. At its core, the prediction model uses a recurrent neural network that processes the entire protein sequence and an attention mechanism identifying protein regions important for the subcellular localization. The model was trained and tested on a protein dataset extracted from one of the latest UniProt releases, in which experimentally annotated proteins follow more stringent criteria than previously. We demonstrate that our model achieves a good accuracy (78% for 10 categories; 92% for membrane-bound or soluble), outperforming current state-of-the-art algorithms, including those relying on homology information. The method is available as a web server at http://www.cbs.dtu.dk/services/DeepLoc. Example code is available at https://github.com/JJAlmagro/subcellular_localization. The dataset is available at http://www.cbs.dtu.dk/services/DeepLoc/data.php. jjalma@dtu.dk.

  2. Proteomic analysis of lysine acetylation sites in rat tissues reveals organ specificity and subcellular patterns

    DEFF Research Database (Denmark)

    Lundby, Alicia; Hansen, Kasper Lage; Weinert, Brian Tate

    2012-01-01

    that the subcellular acetylation distribution is tissue-type dependent and that acetylation targets tissue-specific pathways involved in fundamental physiological processes. We compare lysine acetylation patterns for rat as well as human skeletal muscle biopsies and demonstrate its general involvement in muscle...

  3. Subcellular localization of Bombyx mori ribosomal protein S3a and ...

    African Journals Online (AJOL)

    Subcellular localization of Bombyx mori ribosomal protein S3a and effect of its over-expression on BmNPV infection. Z Wu-song, B Xian-xun, X Jia-ping, Y Zheng-ying, Y Ying, W Hui-ling, W Wen-bing ...

  4. MultiLoc2: integrating phylogeny and Gene Ontology terms improves subcellular protein localization prediction

    Directory of Open Access Journals (Sweden)

    Kohlbacher Oliver

    2009-09-01

    Full Text Available Abstract Background Knowledge of subcellular localization of proteins is crucial to proteomics, drug target discovery and systems biology since localization and biological function are highly correlated. In recent years, numerous computational prediction methods have been developed. Nevertheless, there is still a need for prediction methods that show more robustness and higher accuracy. Results We extended our previous MultiLoc predictor by incorporating phylogenetic profiles and Gene Ontology terms. Two different datasets were used for training the system, resulting in two versions of this high-accuracy prediction method. One version is specialized for globular proteins and predicts up to five localizations, whereas a second version covers all eleven main eukaryotic subcellular localizations. In a benchmark study with five localizations, MultiLoc2 performs considerably better than other methods for animal and plant proteins and comparably for fungal proteins. Furthermore, MultiLoc2 performs clearly better when using a second dataset that extends the benchmark study to all eleven main eukaryotic subcellular localizations. Conclusion MultiLoc2 is an extensive high-performance subcellular protein localization prediction system. By incorporating phylogenetic profiles and Gene Ontology terms MultiLoc2 yields higher accuracies compared to its previous version. Moreover, it outperforms other prediction systems in two benchmarks studies. MultiLoc2 is available as user-friendly and free web-service, available at: http://www-bs.informatik.uni-tuebingen.de/Services/MultiLoc2.

  5. Different subcellular locations of secretome components of Gram-positive bacteria

    NARCIS (Netherlands)

    Buist, Girbe; Ridder, Anja N. J. A.; Kok, Jan; Kuipers, Oscar P.

    2006-01-01

    Gram-positive bacteria contain different types of secretion systems for the transport of proteins into or across the cytoplasmic membrane. Recent studies on subcellular localization of specific components of these secretion systems and their substrates have shown that they can be present at various

  6. Chagas' disease: humoral response to subcellular fraction of Trypanosoma cruzi in symptomatic and asymptomatic patients.

    Science.gov (United States)

    de Titto, E H; Moreno, M; Braun, M; Segura, E L

    1987-09-01

    The capacity of antibodies in serum from individuals with chronic Chagas' disease to react with antigens in different subcellular fractions of Trypanosoma cruzi varied according to the clinical status of the patients. Antibodies in serum of asymptomatic patients were directed mostly against antigens in the citosol of the parasite, whereas in overtly cardiopathic patients antibodies were directed mostly against antigens in the microsomal fractions.

  7. Organelle-targeting surface-enhanced Raman scattering (SERS) nanosensors for subcellular pH sensing.

    Science.gov (United States)

    Shen, Yanting; Liang, Lijia; Zhang, Shuqin; Huang, Dianshuai; Zhang, Jing; Xu, Shuping; Liang, Chongyang; Xu, Weiqing

    2018-01-25

    The pH value of subcellular organelles in living cells is a significant parameter in the physiological activities of cells. Its abnormal fluctuations are commonly believed to be associated with cancers and other diseases. Herein, a series of surface-enhanced Raman scattering (SERS) nanosensors with high sensitivity and targeting function was prepared for the quantification and monitoring of pH values in mitochondria, nucleus, and lysosome. The nanosensors were composed of gold nanorods (AuNRs) functionalized with a pH-responsive molecule (4-mercaptopyridine, MPy) and peptides that could specifically deliver the AuNRs to the targeting subcellular organelles. The localization of our prepared nanoprobes in specific organelles was confirmed by super-high resolution fluorescence imaging and bio-transmission electron microscopy (TEM) methods. By the targeting ability, the pH values of the specific organelles can be determined by monitoring the vibrational spectral changes of MPy with different pH values. Compared to the cases of reported lysosome and cytoplasm SERS pH sensors, more accurate pH values of mitochondria and nucleus, which could be two additional intracellular tracers for subcellular microenvironments, were disclosed by this SERS approach, further improving the accuracy of discrimination of related diseases. Our sensitive SERS strategy can also be employed to explore crucial physiological and biological processes that are related to subcellular pH fluctuations.

  8. Bovine sperm plasma membrane proteomics through biotinylation and subcellular enrichment.

    Science.gov (United States)

    Kasvandik, Sergo; Sillaste, Gerly; Velthut-Meikas, Agne; Mikelsaar, Aavo-Valdur; Hallap, Triin; Padrik, Peeter; Tenson, Tanel; Jaakma, Ülle; Kõks, Sulev; Salumets, Andres

    2015-06-01

    A significant proportion of mammalian fertilization is mediated through the proteomic composition of the sperm surface. These protein constituents can present as biomarkers to control and regulate breeding of agricultural animals. Previous studies have addressed the bovine sperm cell apical plasma membrane (PM) proteome with nitrogen cavitation enrichment. Alternative workflows would enable to expand the compositional data more globally around the entire sperm's surface. We used a cell surface biotin-labeling in combination with differential centrifugation to enrich sperm surface proteins. Using nano-LC MS/MS, 338 proteins were confidently identified in the PM-enriched proteome. Functional categories of sperm-egg interaction, protein turnover, metabolism as well as molecular t