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Sample records for intracellular compartments contributes

  1. The contribution of TWIK-1 channels to astrocyte K+ current is limited by retention in intracellular compartments

    PubMed Central

    Wang, Wei; Putra, Adhytia; Schools, Gary P.; Ma, Baofeng; Chen, Haijun; Kaczmarek, Leonard K.; Barhanin, Jacques; Lesage, Florian; Zhou, Min

    2013-01-01

    TWIK-1 two-pore domain K+ channels are expressed abundantly in astrocytes. In the present study, we examined the extent to which TWIK-1 contributes to the linear current-voltage (I–V) relationship (passive) K+ membrane conductance, a dominant electrophysiological feature of mature hippocampal astrocytes. Astrocytes from TWIK-1 knockout mice have a more negative resting potential than those from wild type animals and a reduction in both inward rectification and Cs+ permeability. Nevertheless, the overall whole-cell passive conductance is not altered significantly in TWIK-1 knockout astrocytes. The expression of Kir4.1 and TREK-1, two other major astrocytic K+ channels, or of other two-pore K+ channels is not altered in TWIK-1 knockout mice, suggesting that the mild effect of TWIK-1 knockout does not result from compensation by these channels. Fractionation experiments showed that TWIK-1 is primarily localized in intracellular cytoplasmic fractions (55%) and mildly hydrophobic internal compartment fractions (41%), with only 5% in fractions containing plasma membranes. Our study revealed that TWIK-1 proteins are mainly located in the intracellular compartments of hippocampal astrocyte under physiological condition, therefore a minimal contribution of TWIK-1 channels to whole-cell currents is likely attributable to a relatively low level presence of channels in the plasma membrane. PMID:24368895

  2. Intracellular potassium compartments in Nitella axillaris.

    PubMed

    DIAMOND, J M; SOLOMON, A K

    1959-05-20

    Three intracellular compartments for potassium exchange have been observed in intact cells of the giant-celled alga, Nitella axillaris. These compartments have been compared with the exchange properties of isolated subcellular structures. The smallest and fastest compartment (apparent half-time, 23 seconds) appears to involve passive absorption on the cell wall. The next largest (apparent half-time, 5 hours) may represent exchange with the cytoplasmic layer through the plasma membrane, the chloroplasts being in rapid equilibrium with the surrounding cytoplasm. The largest and slowest compartment (apparent half-time, 40 days) has been identified with the central vacuole. The vacuolar membrane and the plasma membrane have similar properties with respect to K permeability. Thus, the experimental data from the whole cell can be accounted for by a structural model of the compartments. Cyanide in concentrations up to 10(-3)M causes no net loss of K. The fastest compartment in Nitella and in higher plants is compared, and the ecological significance of the slow rate of potassium transport in Nitella is discussed.

  3. Targeting intracellular compartments by magnetic polymeric nanoparticles.

    PubMed

    Kocbek, Petra; Kralj, Slavko; Kreft, Mateja Erdani; Kristl, Julijana

    2013-09-27

    Superparamagnetic iron oxide nanoparticles (SPIONs) show a great promise for a wide specter of bioapplications, due to their characteristic magnetic properties exhibited only in the presence of magnetic field. Their advantages in the fields of magnetic drug targeting and imaging are well established and their safety is assumed, since iron oxide nanoparticles have already been approved for in vivo application, however, according to many literature reports the bare metal oxide nanoparticles may cause toxic effects on treated cells. Therefore, it is reasonable to prevent the direct interactions between metal oxide core and surrounding environment. In the current research ricinoleic acid coated maghemite nanoparticles were successfully synthesized, characterized and incorporated in the polymeric matrix, resulting in nanosized magnetic polymeric particles. The carrier system was shown to exhibit superparamagnetic properties and was therefore responsive towards external magnetic field. Bioevaluation using T47-D breast cancer cells confirmed internalization of magnetic polymeric nanoparticles (MNPs) and their intracellular localization in various subcellular compartments, depending on presence/absence of external magnetic field. However, the number of internalized MNPs observed by fluorescent and transmission electron microscopy was relatively low, making such way of targeting effective only for delivery of highly potent drugs. The scanning electron microscopy of treated cells revealed that MNPs influenced the cell adhesion, when external magnetic field was applied, and that treatment resulted in damaged apical plasma membrane right after exposure to the magnetic carrier. On the other hand, MNPs showed only reversibly reduced cellular metabolic activity in concentrations up to 200 μg/ml and, in the tested concentration the cell cycle distribution was within the normal range, indicating safety of the established magnetic carrier system for the treated cells.

  4. Delivery of a Salmonella Typhi exotoxin from a host intracellular compartment.

    PubMed

    Spanò, Stefania; Ugalde, Juan E; Galán, Jorge E

    2008-01-17

    Salmonella Typhi, an exclusive human pathogen and the cause of typhoid fever, expresses a functional cytolethal distending toxin for which only the active subunit, CdtB, has been identified. Here, we show that PltA and PltB, which are encoded in the same pathogenicity islet as cdtB, associate with CdtB to form a multipartite toxin. PltA and PltB are homologs of components of the pertussis toxin, including its ADP-ribosyl transferase subunit. We also show that PltA and PltB are required for the delivery of CdtB from an intracellular compartment to target cells via autocrine and paracrine pathways. We hypothesize that this toxin, which we have named "typhoid toxin," and its delivery mechanism may contribute to S. Typhi's unique virulence properties.

  5. Release of lipopolysaccharide from intracellular compartments containing Salmonella typhimurium to vesicles of the host epithelial cell.

    PubMed Central

    Garcia-del Portillo, F; Stein, M A; Finlay, B B

    1997-01-01

    The biological effects of bacterial lipopolysaccharide (LPS) on eucaryotic cells have traditionally been characterized following extracellular challenge of LPS on susceptible cells. In this study, we report the capacity of Salmonella typhimurium to release LPS once it is located in the intracellular environment of cultured epithelial cells. LPS is liberated from vacuolar compartments, where intracellular bacteria reside, to vesicles present in the host cell cytosol. The vesicle-associated LPS is detected in infected cells from the time when invading bacteria enter the host cell. Release of LPS is restricted to S. typhimurium-infected cells, with no LPS observed in neighboring uninfected cells, suggesting that dissemination of LPS occurs entirely within the intracellular environment of the infected cell. The amount of LPS present in host vesicles reaches a maximum when intracellular S. typhimurium cells start to proliferate, a time at which the entire host cell cytosol is filled with numerous vesicles containing LPS. All these data support the concept that intracellular bacterial pathogens might signal the host cell from intracellular locations by releasing bioactive bacterial components such as LPS. PMID:8975888

  6. Targeting a c-Myc inhibitory polypeptide to specific intracellular compartments using cell penetrating peptides.

    PubMed

    Bidwell, Gene L; Davis, Aisha N; Raucher, Drazen

    2009-04-01

    The therapeutic index of current anti-cancer chemotherapeutics can be improved by two major mechanisms: 1) developing drugs which are specifically toxic to the cancer cells and 2) developing methods to deliver drugs to the tumor site. In an attempt to combine these approaches, we developed a thermally responsive polypeptide inhibitor of c-Myc. This polypeptide is based on the thermally responsive Elastin-like polypeptide (ELP). When injected systemically, ELP-fused drugs will aggregate and accumulate at the tumor site where local hyperthermia is applied. ELP was fused to a peptide which blocks c-Myc/Max dimerization (H1), thereby inhibiting transcription activation by c-Myc (ELP-H1). In this study, the cellular uptake, intracellular distribution, and potency of the Pen, Tat and Bac cell penetrating peptides fused to ELP-H1 were evaluated. While Pen-ELP-H1 and Tat-ELP-H1 were localized in the cytoplasm, Bac-ELP-H1 localized to the nucleus in a subset of the cells and was the most potent inhibitor of MCF-7 cell proliferation. This data demonstrates that ELP can be targeted to the desired cellular compartment simply by choice of the CPP used, resulting in a more potent nuclear targeted c-Myc inhibitory polypeptide which may be beneficial in cancer therapy.

  7. Physiological Intracellular Crowdedness is Defined by the Perimeter-to-Area Ratio of Sub-Cellular Compartments

    PubMed Central

    Hiroi, Noriko; Okuhara, Takahiro; Kubojima, Takeshi; Iba, Keisuke; Tabira, Akito; Yamashita, Shuji; Okada, Yasunori; Kobayashi, Tetsuya J.; Funahashi, Akira

    2012-01-01

    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. PMID:22936917

  8. Designer amphiphilic proteins as building blocks for the intracellular formation of organelle-like compartments

    NASA Astrophysics Data System (ADS)

    Huber, Matthias C.; Schreiber, Andreas; von Olshausen, Philipp; Varga, Balázs R.; Kretz, Oliver; Joch, Barbara; Barnert, Sabine; Schubert, Rolf; Eimer, Stefan; Kele, Péter; Schiller, Stefan M.

    2015-01-01

    Nanoscale biological materials formed by the assembly of defined block-domain proteins control the formation of cellular compartments such as organelles. Here, we introduce an approach to intentionally ‘program’ the de novo synthesis and self-assembly of genetically encoded amphiphilic proteins to form cellular compartments, or organelles, in Escherichia coli. These proteins serve as building blocks for the formation of artificial compartments in vivo in a similar way to lipid-based organelles. We investigated the formation of these organelles using epifluorescence microscopy, total internal reflection fluorescence microscopy and transmission electron microscopy. The in vivo modification of these protein-based de novo organelles, by means of site-specific incorporation of unnatural amino acids, allows the introduction of artificial chemical functionalities. Co-localization of membrane proteins results in the formation of functionalized artificial organelles combining artificial and natural cellular function. Adding these protein structures to the cellular machinery may have consequences in nanobiotechnology, synthetic biology and materials science, including the constitution of artificial cells and bio-based metamaterials.

  9. Designer amphiphilic proteins as building blocks for the intracellular formation of organelle-like compartments.

    PubMed

    Huber, Matthias C; Schreiber, Andreas; von Olshausen, Philipp; Varga, Balázs R; Kretz, Oliver; Joch, Barbara; Barnert, Sabine; Schubert, Rolf; Eimer, Stefan; Kele, Péter; Schiller, Stefan M

    2015-01-01

    Nanoscale biological materials formed by the assembly of defined block-domain proteins control the formation of cellular compartments such as organelles. Here, we introduce an approach to intentionally 'program' the de novo synthesis and self-assembly of genetically encoded amphiphilic proteins to form cellular compartments, or organelles, in Escherichia coli. These proteins serve as building blocks for the formation of artificial compartments in vivo in a similar way to lipid-based organelles. We investigated the formation of these organelles using epifluorescence microscopy, total internal reflection fluorescence microscopy and transmission electron microscopy. The in vivo modification of these protein-based de novo organelles, by means of site-specific incorporation of unnatural amino acids, allows the introduction of artificial chemical functionalities. Co-localization of membrane proteins results in the formation of functionalized artificial organelles combining artificial and natural cellular function. Adding these protein structures to the cellular machinery may have consequences in nanobiotechnology, synthetic biology and materials science, including the constitution of artificial cells and bio-based metamaterials. PMID:25362355

  10. Intracellular lumen formation in Drosophila proceeds via a novel subcellular compartment.

    PubMed

    Nikolova, Linda S; Metzstein, Mark M

    2015-11-15

    Cellular tubes have diverse morphologies, including multicellular, unicellular and subcellular architectures. Subcellular tubes are found prominently within the vertebrate vasculature, the insect breathing system and the nematode excretory apparatus, but how such tubes form is poorly understood. To characterize the cellular mechanisms of subcellular tube formation, we have refined methods of high pressure freezing/freeze substitution to prepare Drosophila larvae for transmission electron microscopic (TEM) analysis. Using our methods, we have found that subcellular tube formation may proceed through a previously undescribed multimembrane intermediate composed of vesicles bound within a novel subcellular compartment. We have also developed correlative light/TEM procedures to identify labeled cells in TEM-fixed larval samples. Using this technique, we have found that Vacuolar ATPase (V-ATPase) and the V-ATPase regulator Rabconnectin-3 are required for subcellular tube formation, probably in a step resolving the intermediate compartment into a mature lumen. In general, our ultrastructural analysis methods could be useful for a wide range of cellular investigations in Drosophila larvae.

  11. Intracellular lumen formation in Drosophila proceeds via a novel subcellular compartment.

    PubMed

    Nikolova, Linda S; Metzstein, Mark M

    2015-11-15

    Cellular tubes have diverse morphologies, including multicellular, unicellular and subcellular architectures. Subcellular tubes are found prominently within the vertebrate vasculature, the insect breathing system and the nematode excretory apparatus, but how such tubes form is poorly understood. To characterize the cellular mechanisms of subcellular tube formation, we have refined methods of high pressure freezing/freeze substitution to prepare Drosophila larvae for transmission electron microscopic (TEM) analysis. Using our methods, we have found that subcellular tube formation may proceed through a previously undescribed multimembrane intermediate composed of vesicles bound within a novel subcellular compartment. We have also developed correlative light/TEM procedures to identify labeled cells in TEM-fixed larval samples. Using this technique, we have found that Vacuolar ATPase (V-ATPase) and the V-ATPase regulator Rabconnectin-3 are required for subcellular tube formation, probably in a step resolving the intermediate compartment into a mature lumen. In general, our ultrastructural analysis methods could be useful for a wide range of cellular investigations in Drosophila larvae. PMID:26428009

  12. Mercury-Pollution Induction of Intracellular Lipid Accumulation and Lysosomal Compartment Amplification in the Benthic Foraminifer Ammonia parkinsoniana.

    PubMed

    Frontalini, Fabrizio; Curzi, Davide; Cesarini, Erica; Canonico, Barbara; Giordano, Francesco M; De Matteis, Rita; Bernhard, Joan M; Pieretti, Nadia; Gu, Baohua; Eskelsen, Jeremy R; Jubb, Aaron M; Zhao, Linduo; Pierce, Eric M; Gobbi, Pietro; Papa, Stefano; Coccioni, Rodolfo

    2016-01-01

    Heavy metals such as mercury (Hg) pose a significant health hazard through bioaccumulation and biomagnification. By penetrating cell membranes, heavy metal ions may lead to pathological conditions. Here we examined the responses of Ammonia parkinsoniana, a benthic foraminiferan, to different concentrations of Hg in the artificial sea water. Confocal images of untreated and treated specimens using fluorescent probes (Nile Red and Acridine Orange) provided an opportunity for visualizing the intracellular lipid accumulation and acidic compartment regulation. With increased Hg over time, we observed an increased number of lipid droplets, which may have acted as a detoxifying organelle where Hg is sequestered and biologically inactivated. Further, Hg seems to promote the proliferation of lysosomes both in terms of number and dimension that, at the highest level of Hg, resulted in cell death. We report, for the first time, the presence of Hg within the foraminiferal cell: at the basal part of pores, in the organic linings of the foramen/septa, and as cytoplasmic accumulations. PMID:27603511

  13. Mercury-Pollution Induction of Intracellular Lipid Accumulation and Lysosomal Compartment Amplification in the Benthic Foraminifer Ammonia parkinsoniana.

    PubMed

    Frontalini, Fabrizio; Curzi, Davide; Cesarini, Erica; Canonico, Barbara; Giordano, Francesco M; De Matteis, Rita; Bernhard, Joan M; Pieretti, Nadia; Gu, Baohua; Eskelsen, Jeremy R; Jubb, Aaron M; Zhao, Linduo; Pierce, Eric M; Gobbi, Pietro; Papa, Stefano; Coccioni, Rodolfo

    2016-01-01

    Heavy metals such as mercury (Hg) pose a significant health hazard through bioaccumulation and biomagnification. By penetrating cell membranes, heavy metal ions may lead to pathological conditions. Here we examined the responses of Ammonia parkinsoniana, a benthic foraminiferan, to different concentrations of Hg in the artificial sea water. Confocal images of untreated and treated specimens using fluorescent probes (Nile Red and Acridine Orange) provided an opportunity for visualizing the intracellular lipid accumulation and acidic compartment regulation. With increased Hg over time, we observed an increased number of lipid droplets, which may have acted as a detoxifying organelle where Hg is sequestered and biologically inactivated. Further, Hg seems to promote the proliferation of lysosomes both in terms of number and dimension that, at the highest level of Hg, resulted in cell death. We report, for the first time, the presence of Hg within the foraminiferal cell: at the basal part of pores, in the organic linings of the foramen/septa, and as cytoplasmic accumulations.

  14. Mercury-Pollution Induction of Intracellular Lipid Accumulation and Lysosomal Compartment Amplification in the Benthic Foraminifer Ammonia parkinsoniana

    PubMed Central

    Curzi, Davide; Cesarini, Erica; Canonico, Barbara; Giordano, Francesco M.; De Matteis, Rita; Bernhard, Joan M.; Pieretti, Nadia; Gu, Baohua; Eskelsen, Jeremy R.; Jubb, Aaron M.; Zhao, Linduo; Pierce, Eric M.; Gobbi, Pietro; Papa, Stefano; Coccioni, Rodolfo

    2016-01-01

    Heavy metals such as mercury (Hg) pose a significant health hazard through bioaccumulation and biomagnification. By penetrating cell membranes, heavy metal ions may lead to pathological conditions. Here we examined the responses of Ammonia parkinsoniana, a benthic foraminiferan, to different concentrations of Hg in the artificial sea water. Confocal images of untreated and treated specimens using fluorescent probes (Nile Red and Acridine Orange) provided an opportunity for visualizing the intracellular lipid accumulation and acidic compartment regulation. With increased Hg over time, we observed an increased number of lipid droplets, which may have acted as a detoxifying organelle where Hg is sequestered and biologically inactivated. Further, Hg seems to promote the proliferation of lysosomes both in terms of number and dimension that, at the highest level of Hg, resulted in cell death. We report, for the first time, the presence of Hg within the foraminiferal cell: at the basal part of pores, in the organic linings of the foramen/septa, and as cytoplasmic accumulations. PMID:27603511

  15. Mercury-pollution induction of intracellular lipid accumulation and lysosomal compartment amplification in the benthic foraminifer Ammonia parkinsoniana

    DOE PAGES

    Frontalini, Fabrizio; Curzi, Davide; Cesarini, Erica; Canonico, Barbara; Giordano, Francesco M.; De Matteis, Rita; Bernhard, Joan M.; Pieretti, Nadia; Gu, Baohua; Eskelsen, Jeremy R.; et al

    2016-09-07

    In this study, heavy metals such as mercury (Hg) pose a significant health hazard through bioaccumulation and biomagnification. By penetrating cell membranes, heavy metal ions may lead to pathological conditions. Here we examined the responses of Ammonia parkinsoniana, a benthic foraminiferan, to different concentrations of Hg in the artificial sea water. Confocal images of untreated and treated specimens using fluorescent probes (Nile Red and Acridine Orange) provided an opportunity for visualizing the intracellular lipid accumulation and acidic compartment regulation. With increased Hg over time, we observed an increased number of lipid droplets, which may have acted as a detoxifying organellemore » where Hg is sequestered and biologically inactivated. Further, Hg seems to promote the proliferation of lysosomes both in terms of number and dimension that, at the highest level of Hg, resulted in cell death. We report, for the first time, the presence of Hg within the foraminiferal cell: at the basal part of pores, in the organic linings of the foramen/septa, and as cytoplasmic accumulations.« less

  16. MEMRI and tumors: a method for the evaluation of the contribution of Mn(II) ions in the extracellular compartment.

    PubMed

    Gianolio, Eliana; Arena, Francesca; Di Gregorio, Enza; Pagliarin, Roberto; Delbianco, Martina; Baio, Gabriella; Aime, Silvio

    2015-09-01

    The purpose of the work was to set-up a simple method to evaluate the contribution of Mn(2+) ions in the intra- and extracellular tumor compartments in a MEMRI experiment. This task has been tackled by "silencing" the relaxation enhancement arising from Mn(2+) ions in the extracellular space. In vitro relaxometric measurements allowed assessment of the sequestering activity of DO2A (1,4,7,10-tetraazacyclododecane-1,7-diacetic acid) towards Mn(2+) ions, as the addition of Ca-DO2A to a solution of MnCl2 causes a drop of relaxivity upon the formation of the highly stable and low-relaxivity Mn-DO2A. It has been proved that the sequestering ability of DO2A towards Mn(2+) ions is also fully effective in the presence of serum albumin. Moreover, it has been shown that Mn-DO2A does not enter cell membranes, nor does the presence of Ca-DO2A in the extracellular space prompt migration of Mn ions from the intracellular compartment. On this basis the in vivo, instantaneous, drop in SE% (percent signal enhancement) in T1 -weighted images is taken as evidence of the sequestration of extracellular Mn(2+) ions upon addition of Ca-DO2A. By applying the method to B16F10 tumor bearing mice, T1 decrease is readily detected in the tumor region, whereas a negligible change in SE% is observed in kidneys, liver and muscle. The relaxometric MRI results have been validated by ICP-MS measurements.

  17. Contributions of intracellular ions to kv channel voltage sensor dynamics.

    PubMed

    Goodchild, Samuel J; Fedida, David

    2012-01-01

    Voltage-sensing domains (VSDs) of Kv channels control ionic conductance through coupling of the movement of charged residues in the S4 segment to conformational changes at the cytoplasmic region of the pore domain, that allow K(+) ions to flow. Conformational transitions within the VSD are induced by changes in the applied voltage across the membrane field. However, several other factors not directly linked to the voltage-dependent movement of charged residues within the voltage sensor impact the dynamics of the voltage sensor, such as inactivation, ionic conductance, intracellular ion identity, and block of the channel by intracellular ligands. The effect of intracellular ions on voltage sensor dynamics is of importance in the interpretation of gating current measurements and the physiology of pore/voltage sensor coupling. There is a significant amount of variability in the reported kinetics of voltage sensor deactivation kinetics of Kv channels attributed to different mechanisms such as open state stabilization, immobilization, and relaxation processes of the voltage sensor. Here we separate these factors and focus on the causal role that intracellular ions can play in allosterically modulating the dynamics of Kv voltage sensor deactivation kinetics. These considerations are of critical importance in understanding the molecular determinants of the complete channel gating cycle from activation to deactivation.

  18. Bem3, a Cdc42 GTPase-activating protein, traffics to an intracellular compartment and recruits the secretory Rab GTPase Sec4 to endomembranes

    PubMed Central

    Mukherjee, Debarati; Sen, Arpita; Boettner, Douglas R.; Fairn, Gregory D.; Schlam, Daniel; Bonilla Valentin, Fernando J.; Michael McCaffery, J.; Hazbun, Tony; Staiger, Chris J.; Grinstein, Sergio; Lemmon, Sandra K.; Claudio Aguilar, R.

    2013-01-01

    Summary Cell polarity is essential for many cellular functions including division and cell-fate determination. Although RhoGTPase signaling and vesicle trafficking are both required for the establishment of cell polarity, the mechanisms by which they are coordinated are unclear. Here, we demonstrate that the yeast RhoGAP (GTPase activating protein), Bem3, is targeted to sites of polarized growth by the endocytic and recycling pathways. Specifically, deletion of SLA2 or RCY1 led to mislocalization of Bem3 to depolarized puncta and accumulation in intracellular compartments, respectively. Bem3 partitioned between the plasma membrane and an intracellular membrane-bound compartment. These Bem3-positive structures were polarized towards sites of bud emergence and were mostly observed during the pre-mitotic phase of apical growth. Cell biological and biochemical approaches demonstrated that this intracellular Bem3 compartment contained markers for both the endocytic and secretory pathways, which were reminiscent of the Spitzenkörper present in the hyphal tips of growing fungi. Importantly, Bem3 was not a passive cargo, but recruited the secretory Rab protein, Sec4, to the Bem3-containing compartments. Moreover, Bem3 deletion resulted in less efficient localization of Sec4 to bud tips during early stages of bud emergence. Surprisingly, these effects of Bem3 on Sec4 were independent of its GAP activity, but depended on its ability to efficiently bind endomembranes. This work unveils unsuspected and important details of the relationship between vesicle traffic and elements of the cell polarity machinery: (1) Bem3, a cell polarity and peripherally associated membrane protein, relies on vesicle trafficking to maintain its proper localization; and (2) in turn, Bem3 influences secretory vesicle trafficking. PMID:23943876

  19. Identification and characterization of two distinct intracellular GLUT4 pools in rat skeletal muscle: evidence for an endosomal and an insulin-sensitive GLUT4 compartment.

    PubMed

    Aledo, J C; Lavoie, L; Volchuk, A; Keller, S R; Klip, A; Hundal, H S

    1997-08-01

    In skeletal muscle, acute insulin treatment results in the recruitment of the GLUT4 glucose transporter from intracellular vesicular structures to the plasma membrane. The precise nature of these intracellular GLUT4 stores has, however, remained poorly defined. Using an established skeletal-muscle fractionation procedure we present evidence for the existence of two distinct intracellular GLUT4 compartments. We have shown that after fractionation of crude muscle membranes on a discontinuous sucrose gradient the majority of the GLUT4 immunoreactivity was largely present in two sucrose fractions (30 and 35%, w/w, sucrose; denoted F30 and F35 respectively) containing intracellular membranes of different buoyant densities. Here we show that these fractions contained 44+/-6 and 49+/-7% of the crude membrane GLUT4 reactivity respectively, and could be further discriminated on the basis of their immunoreactivity against specific subcellular antigen markers. Membranes from the F30 fraction were highly enriched in transferrin receptor (TfR) and annexin II, two markers of the early endosome compartment, whereas they were significantly depleted of both GLUT1 and the alpha1-subunit of (Na++K+)-ATPase, two cell-surface markers. Insulin treatment resulted in a significant reduction in GLUT4 content in membranes from the F35 fraction, whereas the amount of GLUT4 in the less dense (F30) fraction remained unaffected by insulin. Immunoprecipitation of GLUT4-containing vesicles from both intracellular fractions revealed that TfR was present in GLUT4 vesicles isolated from membranes from the F30 fraction. In contrast, GLUT4 vesicles from the F35 fraction were devoid of TfR. The aminopeptidase, vp165, was present in GLUT4 vesicles from both F30 and F35; however, vesicles isolated from F30 contained over twice as much vp165 per unit of GLUT4 than those isolated from F35. The biochemical co-localization of vp165/GLUT4 was further substantiated by double-immunogold labelling of ultrathin

  20. Disproportionate Contributions of Select Genomic Compartments and Cell Types to Genetic Risk for Coronary Artery Disease

    PubMed Central

    Won, Hong-Hee; Natarajan, Pradeep; Dobbyn, Amanda; Jordan, Daniel M.; Roussos, Panos; Lage, Kasper; Raychaudhuri, Soumya

    2015-01-01

    Large genome-wide association studies (GWAS) have identified many genetic loci associated with risk for myocardial infarction (MI) and coronary artery disease (CAD). Concurrently, efforts such as the National Institutes of Health (NIH) Roadmap Epigenomics Project and the Encyclopedia of DNA Elements (ENCODE) Consortium have provided unprecedented data on functional elements of the human genome. In the present study, we systematically investigate the biological link between genetic variants associated with this complex disease and their impacts on gene function. First, we examined the heritability of MI/CAD according to genomic compartments. We observed that single nucleotide polymorphisms (SNPs) residing within nearby regulatory regions show significant polygenicity and contribute between 59–71% of the heritability for MI/CAD. Second, we showed that the polygenicity and heritability explained by these SNPs are enriched in histone modification marks in specific cell types. Third, we found that a statistically higher number of 45 MI/CAD-associated SNPs that have been identified from large-scale GWAS studies reside within certain functional elements of the genome, particularly in active enhancer and promoter regions. Finally, we observed significant heterogeneity of this signal across cell types, with strong signals observed within adipose nuclei, as well as brain and spleen cell types. These results suggest that the genetic etiology of MI/CAD is largely explained by tissue-specific regulatory perturbation within the human genome. PMID:26509271

  1. Disproportionate Contributions of Select Genomic Compartments and Cell Types to Genetic Risk for Coronary Artery Disease.

    PubMed

    Won, Hong-Hee; Natarajan, Pradeep; Dobbyn, Amanda; Jordan, Daniel M; Roussos, Panos; Lage, Kasper; Raychaudhuri, Soumya; Stahl, Eli; Do, Ron

    2015-10-01

    Large genome-wide association studies (GWAS) have identified many genetic loci associated with risk for myocardial infarction (MI) and coronary artery disease (CAD). Concurrently, efforts such as the National Institutes of Health (NIH) Roadmap Epigenomics Project and the Encyclopedia of DNA Elements (ENCODE) Consortium have provided unprecedented data on functional elements of the human genome. In the present study, we systematically investigate the biological link between genetic variants associated with this complex disease and their impacts on gene function. First, we examined the heritability of MI/CAD according to genomic compartments. We observed that single nucleotide polymorphisms (SNPs) residing within nearby regulatory regions show significant polygenicity and contribute between 59-71% of the heritability for MI/CAD. Second, we showed that the polygenicity and heritability explained by these SNPs are enriched in histone modification marks in specific cell types. Third, we found that a statistically higher number of 45 MI/CAD-associated SNPs that have been identified from large-scale GWAS studies reside within certain functional elements of the genome, particularly in active enhancer and promoter regions. Finally, we observed significant heterogeneity of this signal across cell types, with strong signals observed within adipose nuclei, as well as brain and spleen cell types. These results suggest that the genetic etiology of MI/CAD is largely explained by tissue-specific regulatory perturbation within the human genome. PMID:26509271

  2. Accumulation of properly folded human type III procollagen molecules in specific intracellular membranous compartments in the yeast Pichia pastoris.

    PubMed

    Keizer-Gunnink, I; Vuorela, A; Myllyharju, J; Pihlajaniemi, T; Kivirikko, K I; Veenhuis, M

    2000-02-01

    It was recently reported that co-expression of the proalpha1(III) chain of human type III procollagen with the subunits of human prolyl 4-hydroxylase in Pichia pastoris produces fully hydroxylated and properly folded recombinant type III procollagen molecules (Vuorela, A., Myllyharju, J., Nissi, R., Pihlajaniemi, T., Kivirikko, K.I., 1997. Assembly of human prolyl 4-hydroxylase and type III collagen in the yeast Pichia pastoris: formation of a stable enzyme tetramer requires coexpression with collagen and assembly of a stable collagen requires coexpression with prolyl 4-hydroxylase. EMBO J. 16, 6702-6712). These properly folded molecules accumulated inside the yeast cell, however, only approximately 10% were found in the culture medium. We report here that replacement of the authentic signal sequence of the human proalpha1(III) with the Saccharomyces cerevisiae alpha mating factor prepro sequence led only to a minor increase in the amount secreted. Immunoelectron microscopy studies indicated that the procollagen molecules accumulate in specific membranous vesicular compartments that are closely associated with the nuclear membrane. Prolyl 4-hydroxylase, an endoplasmic reticulum (ER) lumenal enzyme, was found to be located in the same compartments. Non-helical proalpha1(III) chains produced by expression without recombinant prolyl 4-hydroxylase likewise accumulated within these compartments. The data indicate that properly folded recombinant procollagen molecules accumulate within the ER and do not proceed further in the secretory pathway. This may be related to the large size of the procollagen molecule. PMID:10686423

  3. Anomalous bilateral contribution of extensor pollicis longus and muscle fusion of the first compartment of the wrist

    PubMed Central

    Rosa, Rodrigo César; de Oliveira, Kennedy Martinez; Léo, Jorge Alfredo; Elias, Bruno Adriano Borges; dos Santos, Paulo Ricardo; de Santiago, Hildemberg Agostinho Rocha

    2016-01-01

    Knowledge of the anatomical variations of the muscles of the first dorsal compartments of the wrist is clinically relevant to De Quervain's tenosynovitis and to reconstructive surgeries. In the literature, there are many reports of the presence of multiple insertion tendons in the first dorsal compartment of the wrist, but few reports describe occurrences of fusion and muscle contributions. This case report describes an anomalous bilateral contribution of the extensor pollicis longus. This anomalous contribution was found through a slender auxiliary tendon that crossed laterally under the extensor retinaculum, entered the first dorsal compartment of the wrist and merged with the tendon of the extensor pollicis brevis muscle. In the same cadaver in which this contribution was present, there was atypical muscle fusion of the abductor pollicis longus muscle and extensor pollicis brevis muscle. In conclusion, anomalous bilateral contribution of the extensor pollicis longus muscle and atypical muscle fusion, concomitant with a variant insertion pattern, are the highlight of this case report. Furthermore, it is concluded that additional tendons may be effectively used in reconstructive surgeries, but that there is a need for knowledge of the possible numerical and positional variations of these tendons, with a view to making more effective surgical plans. PMID:27069895

  4. Immunological mechanisms contributing to the double burden of diabetes and intracellular bacterial infections

    PubMed Central

    Hodgson, Kelly; Morris, Jodie; Bridson, Tahnee; Govan, Brenda; Rush, Catherine; Ketheesan, Natkunam

    2015-01-01

    Diabetes has been recognized as an important risk factor for a variety of intracellular bacterial infections, but research into the dysregulated immune mechanisms contributing to the impaired host–pathogen interactions is in its infancy. Diabetes is characterized by a chronic state of low-grade inflammation due to activation of pro-inflammatory mediators and increased formation of advanced glycation end products. Increased oxidative stress also exacerbates the chronic inflammatory processes observed in diabetes. The reduced phagocytic and antibacterial activity of neutrophils and macrophages provides an intracellular niche for the pathogen to replicate. Phagocytic and antibacterial dysfunction may be mediated directly through altered glucose metabolism and oxidative stress. Furthermore, impaired activation of natural killer cells contributes to decreased levels of interferon-γ, required for promoting macrophage antibacterial mechanisms. Together with impaired dendritic cell function, this impedes timely activation of adaptive immune responses. Increased intracellular oxidation of antigen-presenting cells in individuals with diabetes alters the cytokine profile generated and the subsequent balance of T-cell immunity. The establishment of acute intracellular bacterial infections in the diabetic host is associated with impaired T-cell-mediated immune responses. Concomitant to the greater intracellular bacterial burden and potential cumulative effect of chronic inflammatory processes, late hyper-inflammatory cytokine responses are often observed in individuals with diabetes, contributing to systemic pathology. The convergence of intracellular bacterial infections and diabetes poses new challenges for immunologists, providing the impetus for multidisciplinary research. PMID:25262977

  5. Probing the metabolic water contribution to intracellular water using oxygen isotope ratios of PO4

    NASA Astrophysics Data System (ADS)

    Li, Hui; Yu, Chan; Wang, Fei; Chang, Sae Jung; Yao, Jun; Blake, Ruth E.

    2016-05-01

    Knowledge of the relative contributions of different water sources to intracellular fluids and body water is important for many fields of study, ranging from animal physiology to paleoclimate. The intracellular fluid environment of cells is challenging to study due to the difficulties of accessing and sampling the contents of intact cells. Previous studies of multicelled organisms, mostly mammals, have estimated body water composition—including metabolic water produced as a byproduct of metabolism—based on indirect measurements of fluids averaged over the whole organism (e.g., blood) combined with modeling calculations. In microbial cells and aquatic organisms, metabolic water is not generally considered to be a significant component of intracellular water, due to the assumed unimpeded diffusion of water across cell membranes. Here we show that the 18O/16O ratio of PO4 in intracellular biomolecules (e.g., DNA) directly reflects the O isotopic composition of intracellular water and thus may serve as a probe allowing direct sampling of the intracellular environment. We present two independent lines of evidence showing a significant contribution of metabolic water to the intracellular water of three environmentally diverse strains of bacteria. Our results indicate that ˜30-40% of O in PO4 comprising DNA/biomass in early stationary phase cells is derived from metabolic water, which bolsters previous results and also further suggests a constant metabolic water value for cells grown under similar conditions. These results suggest that previous studies assuming identical isotopic compositions for intracellular/extracellular water may need to be reconsidered.

  6. Probing the metabolic water contribution to intracellular water using oxygen isotope ratios of PO4

    NASA Astrophysics Data System (ADS)

    Li, Hui; Yu, Chan; Wang, Fei; Chang, Sae Jung; Yao, Jun; Blake, Ruth E.

    2016-05-01

    Knowledge of the relative contributions of different water sources to intracellular fluids and body water is important for many fields of study, ranging from animal physiology to paleoclimate. The intracellular fluid environment of cells is challenging to study due to the difficulties of accessing and sampling the contents of intact cells. Previous studies of multicelled organisms, mostly mammals, have estimated body water composition—including metabolic water produced as a byproduct of metabolism—based on indirect measurements of fluids averaged over the whole organism (e.g., blood) combined with modeling calculations. In microbial cells and aquatic organisms, metabolic water is not generally considered to be a significant component of intracellular water, due to the assumed unimpeded diffusion of water across cell membranes. Here we show that the 18O/16O ratio of PO4 in intracellular biomolecules (e.g., DNA) directly reflects the O isotopic composition of intracellular water and thus may serve as a probe allowing direct sampling of the intracellular environment. We present two independent lines of evidence showing a significant contribution of metabolic water to the intracellular water of three environmentally diverse strains of bacteria. Our results indicate that ˜30–40% of O in PO4 comprising DNA/biomass in early stationary phase cells is derived from metabolic water, which bolsters previous results and also further suggests a constant metabolic water value for cells grown under similar conditions. These results suggest that previous studies assuming identical isotopic compositions for intracellular/extracellular water may need to be reconsidered.

  7. [Viscoelastic properties of isolated papillary muscle: contributions of connective tissue skeleton and intracellular matrix].

    PubMed

    Protsenko, Iu L; Kobelev, A V; Lukin, O N; Balakin, A A; Smoliuk, L T

    2009-07-01

    Peculiarities of viscoelastic behavior of rabbit papillary muscle in passive state are studied by transversal versus longitudinal deformation curves, stress-strain and hysteresis curves, and stress relaxation curves under ramp stretching. The papillary muscle was chosen because of mostly longitudinal orientation of fibers and its elongated shape, which both make it as an appropriate model for uniaxial tests. The problem of evaluation of connective tissue protein structures and intracellular matrix contribution into the properties under consideration is solved by using the maceration method to remove intracellular structures. The different contribution of intracellular and extracellular protein features into total properties of a papillary muscle leads to nonlinearity of myocardial viscoelastic properties, such as the increase of differential elastic module and relaxation time with deformation.

  8. Drug resistance to paclitaxel is not only associated with ABCB1 mRNA expression but also with drug accumulation in intracellular compartments in human lung cancer cell lines.

    PubMed

    Shimomura, Masanori; Yaoi, Takeshi; Itoh, Kyoko; Kato, Daishiro; Terauchi, Kunihiko; Shimada, Junichi; Fushiki, Shinji

    2012-04-01

    In order to clarify the mechanisms of resistance to paclitaxel in lung cancer, three human lung cancer cell lines which exhibit different sensitivity to paclitaxel were investigated from the following viewpoints: overexpression of ATP-binding cassette, sub-family B, member 1 (ABCB1), mutations on paclitaxel binding site of β-tubulin genes, quantity of polymerized tubulin and the intracellular localization of paclitaxel. ABCB1 expression was evaluated by real-time RT-PCR. No correlations were noted between the ABCB1 expression in the sensitive and resistant cell lines at the mRNA level. No mutations on the paclitaxel binding site of the β-tubulin genes were detected in either the resistant or sensitive cells. Live cell images obtained by confocal laser microscopy revealed that the resistant cell line, RERF-LC-KJ, had more accumulation of Oregon Green® 488 conjugated paclitaxel in the lysosomal and extra-lysosomal compartments of cytoplasm than other cell lines. The results obtained in this study indicated that the changes in the subcellular localization could contribute to the production of paclitaxel resistance in lung cancer cell lines. Further studies should be conducted to elucidate the molecular mechanisms that differentiate the intracellular localization of paclitaxel. PMID:22179563

  9. Drug resistance to paclitaxel is not only associated with ABCB1 mRNA expression but also with drug accumulation in intracellular compartments in human lung cancer cell lines

    PubMed Central

    SHIMOMURA, MASANORI; YAOI, TAKESHI; ITOH, KYOKO; KATO, DAISHIRO; TERAUCHI, KUNIHIKO; SHIMADA, JUNICHI; FUSHIKI, SHINJI

    2012-01-01

    In order to clarify the mechanisms of resistance to paclitaxel in lung cancer, three human lung cancer cell lines which exhibit different sensitivity to paclitaxel were investigated from the following viewpoints: overexpression of ATP-binding cassette, sub-family B, member 1 (ABCB1), mutations on paclitaxel binding site of β-tubulin genes, quantity of polymerized tubulin and the intracellular localization of paclitaxel. ABCB1 expression was evaluated by real-time RT-PCR. No correlations were noted between the ABCB1 expression in the sensitive and resistant cell lines at the mRNA level. No mutations on the paclitaxel binding site of the β-tubulin genes were detected in either the resistant or sensitive cells. Live cell images obtained by confocal laser microscopy revealed that the resistant cell line, RERF-LC-KJ, had more accumulation of Oregon Green® 488 conjugated paclitaxel in the lysosomal and extra-lysosomal compartments of cytoplasm than other cell lines. The results obtained in this study indicated that the changes in the subcellular localization could contribute to the production of paclitaxel resistance in lung cancer cell lines. Further studies should be conducted to elucidate the molecular mechanisms that differentiate the intracellular localization of paclitaxel. PMID:22179563

  10. Facile Synthesis of pH-sensitive Germanium Nanocrystals with High Quantum Yield for Intracellular Acidic Compartment Imaging.

    PubMed

    Li, Feng; Wang, Jing; Sun, Shuqing; Wang, Hai; Tang, Zhiyong; Nie, Guangjun

    2015-04-24

    A green-light emitting germanium nanocrystal-based biosensor to monitor lysosomal pH changes is developed. The Ge nanocrystals are synthesized in an aqueous solution with a significantly enhanced photoluminescence quantum yield of 26%. This synthesis involves a facile solution based route which avoided the use of toxic or environmentally unfriendly agents. Importantly, the photoluminescence intensity of the synthesized Ge nanocrystals is particularly sensitive to changes in pH between 5 and 6. When incubated with cultured cells, the nanocrystals are internalized and subsequently translocated via the lysosomal pathway, and the Ge nanocrystals' fluorescence are greatly enhanced, even when the lysosomal pH is only slightly increased. These results reveal that the Ge nanocrystals possess high pH sensitivity compared to a commercially available dye, LysoSensor Green DND-189. The fluorescent properties of the Ge nanocrystals are demonstrated to be dependent on both the crystal form and their surface chemistry. The superior fluorescence properties and bioapplicability of the Ge nanocrystals makes them a promising intracellular bioimaging probe for monitoring various pH-sensitive processes in cells.

  11. Analyzing panel acoustic contributions toward the sound field inside the passenger compartment of a full-size automobile.

    PubMed

    Wu, Sean F; Moondra, Manmohan; Beniwal, Ravi

    2015-04-01

    The Helmholtz equation least squares (HELS)-based nearfield acoustical holography (NAH) is utilized to analyze panel acoustic contributions toward the acoustic field inside the interior region of an automobile. Specifically, the acoustic power flows from individual panels are reconstructed, and relative contributions to sound pressure level and spectrum at any point of interest are calculated. Results demonstrate that by correlating the acoustic power flows from individual panels to the field acoustic pressure, one can correctly locate the panel allowing the most acoustic energy transmission into the vehicle interior. The panel on which the surface acoustic pressure amplitude is the highest should not be used as indicative of the panel responsible for the sound field in the vehicle passenger compartment. Another significant advantage of this HELS-based NAH is that measurements of the input data only need to be taken once by using a conformal array of microphones in the near field, and ranking of panel acoustic contributions to any field point can be readily performed. The transfer functions between individual panels of any vibrating structure to the acoustic pressure anywhere in space are calculated not measured, thus significantly reducing the time and effort involved in panel acoustic contributions analyses.

  12. Raised Intracellular Calcium Contributes to Ischemia-Induced Depression of Evoked Synaptic Transmission

    PubMed Central

    Jalini, Shirin; Ye, Hui; Tonkikh, Alexander A.; Charlton, Milton P.; Carlen, Peter L.

    2016-01-01

    Oxygen-glucose deprivation (OGD) leads to depression of evoked synaptic transmission, for which the mechanisms remain unclear. We hypothesized that increased presynaptic [Ca2+]i during transient OGD contributes to the depression of evoked field excitatory postsynaptic potentials (fEPSPs). Additionally, we hypothesized that increased buffering of intracellular calcium would shorten electrophysiological recovery after transient ischemia. Mouse hippocampal slices were exposed to 2 to 8 min of OGD. fEPSPs evoked by Schaffer collateral stimulation were recorded in the stratum radiatum, and whole cell current or voltage clamp recordings were performed in CA1 neurons. Transient ischemia led to increased presynaptic [Ca2+]i, (shown by calcium imaging), increased spontaneous miniature EPSP/Cs, and depressed evoked fEPSPs, partially mediated by adenosine. Buffering of intracellular Ca2+ during OGD by membrane-permeant chelators (BAPTA-AM or EGTA-AM) partially prevented fEPSP depression and promoted faster electrophysiological recovery when the OGD challenge was stopped. The blocker of BK channels, charybdotoxin (ChTX), also prevented fEPSP depression, but did not accelerate post-ischemic recovery. These results suggest that OGD leads to elevated presynaptic [Ca2+]i, which reduces evoked transmitter release; this effect can be reversed by increased intracellular Ca2+ buffering which also speeds recovery. PMID:26934214

  13. Listeria monocytogenes σH Contributes to Expression of Competence Genes and Intracellular Growth

    PubMed Central

    Medrano Romero, Veronica

    2016-01-01

    ABSTRACT The alternative sigma factor σH has two functions in Gram-positive bacteria: it regulates sporulation and the development of genetic competence. Listeria monocytogenes is a nonsporulating species in which competence has not yet been detected. Nevertheless, the main competence regulators and a series of orthologous genes that form the competence machinery are present in its genome; some of the competence genes play a role in optimal phagosomal escape. In this study, strains overexpressing σH and strains with a σH deletion were used to elucidate the contribution of σH to the expression of the competence machinery genes in L. monocytogenes. Gene expression analysis showed that σH is, indeed, involved in comG and comE regulation. Unexpectedly, we observed a unique regulation scheme in which σH and the transcription factor ComK were involved. Population-level analysis showed that even with the overexpression of both factors, only a fraction of the cells expressed the competence machinery genes. Although we could not detect competence, σH was crucial for phagosomal escape, which implies that this alternative sigma factor has specifically evolved to regulate the L. monocytogenes intracellular life cycle. IMPORTANCE Listeria monocytogenes can be an intracellular pathogen capable of causing serious infections in humans and animal species. Recently, the competence machinery genes were described as being necessary for optimal phagosomal escape, in which the transcription factor ComK plays an important role. On the other hand, our previous phylogenetic analysis suggested that the alternative sigma factor σH might play a role in the regulation of competence genes. The present study shows that some of the competence genes belong to the σH regulon and, importantly, that σH is essential for intracellular growth, implying a unique physiological role of σH among Firmicutes. PMID:26833412

  14. Intracellular proteoglycans.

    PubMed Central

    Kolset, Svein Olav; Prydz, Kristian; Pejler, Gunnar

    2004-01-01

    Proteoglycans (PGs) are proteins with glycosaminoglycan chains, are ubiquitously expressed and have a wide range of functions. PGs in the extracellular matrix and on the cell surface have been the subject of extensive structural and functional studies. Less attention has so far been given to PGs located in intracellular compartments, although several reports suggest that these have biological functions in storage granules, the nucleus and other intracellular organelles. The purpose of this review is, therefore, to present some of these studies and to discuss possible functions linked to PGs located in different intracellular compartments. Reference will be made to publications relevant for the topics we present. It is beyond the scope of this review to cover all publications on PGs in intracellular locations. PMID:14759226

  15. Contribution of Mesenteric Lymph Nodes and GALT to the Intestinal Foxp3+ Regulatory T-Cell Compartment

    PubMed Central

    Geem, Duke; Ngo, Vu; Harusato, Akihito; Chassaing, Benoit; Gewirtz, Andrew T.; Newberry, Rodney D.; Denning, Timothy L.

    2016-01-01

    SUMMARY This study showed that the absence of CCR7 or mesenteric lymph nodes/gut-associated lymphoid tissue did not appreciably impact total intestinal Foxp3+ regulatory T cell representation in the steady-state. However, mesenteric lymph nodes/GALT are required for normal peripherally induced Foxp3+ regulatory T cell differentiation in the small intestine, but not in the large intestine. BACKGROUND & AIMS Foxp3+ regulatory T cells (Tregs) in the intestine promote immune tolerance to enteric antigens. Previous studies have shown that C-C chemokine receptor 7 (CCR7)-dependent migration of intestinal dendritic cells to the mesenteric lymph nodes (mLN) is involved in peripheral Foxp3+ Treg accumulation in the intestine and the establishment of oral tolerance. However, the relative contribution of this CCR7+ dendritic cell–mLN–Treg axis to the total intestinal Foxp3+ Treg pool during the steady-state remains unclear. In this study, the contribution of CCR7, as well as the mLN and gut-associated lymphoid tissue (GALT), to the intestinal Foxp3+ Treg compartment in the small intestine (SI) and large intestine (LI) was assessed. METHODS Intestinal Foxp3+ Tregs were quantitated in Ccr7−/− mice and in mice devoid of secondary lymphoid organs—including mLN and GALT—owing to a deficiency in lymphotoxin (LT) signaling. Specific analyses of Foxp3+Helios+ thymically derived (t)Tregs and Foxp3+Helios− peripherally derived (p) Tregs in the SI and LI, as well as the role for them LN in supporting Foxp3+ pTreg development using the B6.Cg-Tg(TcraTcrb) 425Cbn/J/ovalbumin (OVA) feeding system, were performed. RESULTS Foxp3+ Tregs were enriched in the intestine relative to the mLN, independent of CCR7. In the absence of the mLN and GALT, normal frequency and numbers of Foxp3+ Tregs were observed in LTα-deficient (Lta−/−) mice. However, Foxp3+Helios− pTregs were decreased in the SI of Lta−/− mice, corresponding with defective Foxp3+ pTreg expansion to OVA. In the

  16. Arabidopsis GPAT9 contributes to synthesis of intracellular glycerolipids but not surface lipids

    PubMed Central

    Singer, Stacy D.; Chen, Guanqun; Mietkiewska, Elzbieta; Tomasi, Pernell; Jayawardhane, Kethmi; Dyer, John M.; Weselake, Randall J.

    2016-01-01

    GLYCEROL-3-PHOSPHATE ACYLTRANSFERASE (GPAT) genes encode enzymes involved in glycerolipid biosynthesis in plants. Ten GPAT homologues have been identified in Arabidopsis. GPATs 4–8 have been shown to be involved in the production of extracellular lipid barrier polyesters. Recently, GPAT9 was reported to be essential for triacylglycerol (TAG) biosynthesis in developing Arabidopsis seeds. The enzymatic properties and possible functions of GPAT9 in surface lipid, polar lipid and TAG biosynthesis in non-seed organs, however, have not been investigated. Here we show that Arabidopsis GPAT9 exhibits sn-1 acyltransferase activity with high specificity for acyl-coenzyme A, thus providing further evidence that this GPAT is involved in storage lipid biosynthesis. We also confirm a role for GPAT9 in seed oil biosynthesis and further demonstrate that GPAT9 contributes to the biosynthesis of both polar lipids and TAG in developing leaves, as well as lipid droplet production in developing pollen grains. Conversely, alteration of constitutive GPAT9 expression had no obvious effects on surface lipid biosynthesis. Taken together, these studies expand our understanding of GPAT9 function to include modulation of several different intracellular glycerolipid pools in plant cells. PMID:27325892

  17. Intracellular microRNA profiles form in the Xenopus laevis oocyte that may contribute to asymmetric cell division

    PubMed Central

    Sidova, Monika; Sindelka, Radek; Castoldi, Mirco; Benes, Vladimir; Kubista, Mikael

    2015-01-01

    Asymmetric distribution of fate determinants within cells is an essential biological strategy to prepare them for asymmetric division. In this work we measure the intracellular distribution of 12 maternal microRNAs (miRNA) along the animal-vegetal axis of the Xenopus laevis oocyte using qPCR tomography. We find the miRNAs have distinct intracellular profiles that resemble two out of the three profiles we previously observed for mRNAs. Our results suggest that miRNAs in addition to proteins and mRNAs may have asymmetric distribution within the oocyte and may contribute to asymmetric cell division as cell fate determinants. PMID:26059897

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

    NASA Astrophysics Data System (ADS)

    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.

  19. Proteolytic targeting of Rab29 by an effector protein distinguishes the intracellular compartments of human-adapted and broad-host Salmonella.

    PubMed

    Spanò, Stefania; Liu, Xiaoyun; Galán, Jorge E

    2011-11-01

    Unlike broad-host Salmonella serovars, which cause self-limiting disease, Salmonella enterica serovar Typhi can infect only humans causing typhoid fever, a life-threatening systemic disease. The molecular bases for these differences are presently unknown. Here we show that the GTPase Rab29 (Rab7L1) distinguishes the intracellular vacuole of human-adapted and broad-host Salmonella serovars. A screen to identify host factors required for the export of typhoid toxin, which is exclusively encoded by the human-specific Salmonella enterica serovars Typhi (S. Typhi) and Paratyphi (S. Paratyphi) identified Rab29. We found that Rab29 is recruited to the S. Typhi-containing vacuole but not to vacuoles containing broad-host Salmonella. We observed that in cells infected with broad-host Salmonella Rab29 is specifically cleaved by the proteolytic activity of GtgE, a unique type III secretion effector protein that is absent from S. Typhi. An S. Typhi strain engineered to express GtgE and therefore able to cleave Rab29 exhibited increased intracellular replication in human macrophages. These findings indicate significant differences in the intracellular biology of human-adapted and broad-host Salmonella and show how subtle differences in the assortment of effector proteins encoded by highly related pathogens can have a major impact in their biology.

  20. Contributions of epsinR and gadkin to clathrin-mediated intracellular trafficking

    PubMed Central

    Hirst, Jennifer; Edgar, James R.; Borner, Georg H. H.; Li, Sam; Sahlender, Daniela A.; Antrobus, Robin; Robinson, Margaret S.

    2015-01-01

    The precise functions of most of the proteins that participate in clathrin-mediated intracellular trafficking are unknown. We investigated two such proteins, epsinR and gadkin, using the knocksideways method, which rapidly depletes proteins from the available pool by trapping them onto mitochondria. Although epsinR is known to be an N-ethylmaleimide–sensitive factor attachment protein receptor (SNARE)-specific adaptor, the epsinR knocksideways blocked the production of the entire population of intracellular clathrin-coated vesicles (CCVs), suggesting a more global function. Using the epsinR knocksideways data, we were able to estimate the copy number of all major intracellular CCV proteins. Both sides of the vesicle are densely covered, indicating that CCVs sort their cargo by molecular crowding. Trapping of gadkin onto mitochondria also blocked the production of intracellular CCVs but by a different mechanism: vesicles became cross-linked to mitochondria and pulled out toward the cell periphery. Both phenotypes provide new insights into the regulation of intracellular CCV formation, which could not have been found using more conventional approaches. PMID:26179914

  1. Compartment syndromes

    NASA Technical Reports Server (NTRS)

    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.

  2. Peptide and RNA contributions to iron-sulphur chemical gardens as life's first inorganic compartments, catalysts, capacitors and condensers.

    PubMed

    McGlynn, Shawn E; Kanik, Isik; Russell, Michael J

    2012-06-28

    Hydrothermal chimneys and compartments comprising transition metal sulphides and associated minerals have been proposed as likely locations for the beginnings of life. In laboratory simulations of off-axis alkaline springs, it is shown that the interaction of a simulated alkaline sulphide-bearing submarine vent solution with a primeval anoxic iron-bearing ocean leads to the formation of chimney structures reminiscent of chemical gardens. These chimneys display periodicity in their deposition and exhibit diverse morphologies and mineralogies, affording the possibilities of catalysis and molecular sequestration. The addition of peptides and RNA to the alkaline solution modifies the elemental stoichiometry of the chimneys-perhaps indicating the very initial stage of the organic takeover on the way to living cells by charged organic polymers potentially synthesized in this same environment.

  3. Contribution of the late sodium current to intracellular sodium and calcium overload in rabbit ventricular myocytes treated by anemone toxin.

    PubMed

    Kornyeyev, Dmytro; El-Bizri, Nesrine; Hirakawa, Ryoko; Nguyen, Steven; Viatchenko-Karpinski, Serge; Yao, Lina; Rajamani, Sridharan; Belardinelli, Luiz

    2016-02-01

    Pathological enhancement of late Na(+) current (INa) can potentially modify intracellular ion homeostasis and contribute to cardiac dysfunction. We tested the hypothesis that modulation of late INa can be a source of intracellular Na(+) ([Na(+)]i) overload. Late INa was enhanced by exposing rabbit ventricular myocytes to Anemonia sulcata toxin II (ATX-II) and measured using whole cell patch-clamp technique. [Na(+)]i was determined with fluorescent dye Asante NaTRIUM Green-2 AM. Pacing-induced changes in the dye fluorescence measured at 37°C were more pronounced in ATX-II-treated cells than in control (dye washout prevented calibration). At 22-24°C, resting [Na(+)]i was 6.6 ± 0.8 mM. Treatment with 5 nM ATX-II increased late INa 8.7-fold. [Na(+)]i measured after 2 min of electrical stimulation (1 Hz) was 10.8 ± 1.5 mM and 22.1 ± 1.6 mM (P < 0.001) in the absence and presence of 5 nM ATX-II, respectively. Inhibition of late INa with GS-967 (1 μM) prevented Na(+) i accumulation. A strong positive correlation was observed between the late INa and the pacing-induced increase of [Na(+)]i (R(2) = 0.88) and between the rise in [Na(+)]i and the increases in cytosolic Ca(2+) (R(2) = 0.96). ATX-II, tetrodotoxin, or GS-967 did not affect [Na(+)]i in quiescent myocytes suggesting that late INa was solely responsible for triggering the ATX-II effect on [Na(+)]i. Experiments with pinacidil and E4031 indicate that prolongation of the action potential contributes to as much as 50% of the [Na(+)]i overload associated with the increase in late INa caused by ATX-II. Enhancement of late INa can cause intracellular Na(+) overload in ventricular myocytes. PMID:26637557

  4. Contribution of forensic autopsy to scene reconstruction in mass fire casualties: a case of alleged arson on a floor consisting of small compartments in a building.

    PubMed

    Michiue, Tomomi; Ishikawa, Takaki; Oritani, Shigeki; Maeda, Hitoshi

    2015-01-01

    A fire is an important cause of mass disasters, involving various forensic issues. Before dawn on an early morning, 16 male visitors in their twenties to sixties were killed in a possibly incendiary fire at a 'private video parlor' consisting of small compartments in a building. The main causes of death as determined by forensic autopsy were acute carbon monoxide (CO) intoxication for all of the 15 found-dead victims, and hypoxic-ischemic encephalopathy following acute CO intoxication for a victim who died in hospital. Burns were mild (<20% of body surface) in most victims, except for three victims found between the entrance and the estimated fire-outbreak site; thus, identification was completed without difficulty, supported by DNA analysis. Blood carboxyhemoglobin saturation (COHb) was higher for victims found dead in the inner area. Blood cyanide levels were sublethal, moderately correlated to COHb, but were higher in victims found around the estimated fire-outbreak site. There was no evidence of thinner, alcohol or drug abuse, or an attack of disease as a possible cause of an accidental fire outbreak. These observations contribute to evidence-based reconstruction of the fire disaster, and suggest how deaths could have been prevented by appropriate disaster measures. PMID:25311374

  5. Neutrophils Contribute to the Protection Conferred by ArtinM against Intracellular Pathogens: A Study on Leishmania major

    PubMed Central

    Ricci-Azevedo, Rafael; Oliveira, Aline Ferreira; Conrado, Marina C. A. V.; Carvalho, Fernanda Caroline; Roque-Barreira, Maria Cristina

    2016-01-01

    ArtinM, a D-mannose binding lectin from Artocarpus heterophyllus, has immunomodulatory activities through its interaction with N-glycans of immune cells, culminating with the establishment of T helper type 1 (Th1) immunity. This interaction protects mice against intracellular pathogens, including Leishmania major and Leishmania amazonensis. ArtinM induces neutrophils activation, which is known to account for both resistance to pathogens and host tissue injury. Although exacerbated inflammation was not observed in ArtinM-treated animals, assessment of neutrophil responses to ArtinM is required to envisage its possible application to design a novel immunomodulatory agent based on carbohydrate recognition. Herein, we focus on the mechanisms through which neutrophils contribute to ArtinM-induced protection against Leishmania, without exacerbating inflammation. For this purpose, human neutrophils treated with ArtinM and infected with Leishmania major were analyzed together with untreated and uninfected controls, based on their ability to eliminate the parasite, release cytokines, degranulate, produce reactive oxygen species (ROS), form neutrophil extracellular traps (NETs) and change life span. We demonstrate that ArtinM-stimulated neutrophils enhanced L. major clearance and at least duplicated tumor necrosis factor (TNF) and interleukin-1beta (IL-1β) release; otherwise, transforming growth factor-beta (TGF-β) production was reduced by half. Furthermore, ROS production and cell degranulation were augmented. The life span of ArtinM-stimulated neutrophils decreased and they did not form NETs when infected with L. major. We postulate that the enhanced leishmanicidal ability of ArtinM-stimulated neutrophils is due to augmented release of inflammatory cytokines, ROS production, and cell degranulation, whereas host tissue integrity is favored by their shortened life span and the absence of NET formation. Our results reinforce the idea that ArtinM may be considered an

  6. Neutrophils Contribute to the Protection Conferred by ArtinM against Intracellular Pathogens: A Study on Leishmania major.

    PubMed

    Ricci-Azevedo, Rafael; Oliveira, Aline Ferreira; Conrado, Marina C A V; Carvalho, Fernanda Caroline; Roque-Barreira, Maria Cristina

    2016-04-01

    ArtinM, a D-mannose binding lectin from Artocarpus heterophyllus, has immunomodulatory activities through its interaction with N-glycans of immune cells, culminating with the establishment of T helper type 1 (Th1) immunity. This interaction protects mice against intracellular pathogens, including Leishmania major and Leishmania amazonensis. ArtinM induces neutrophils activation, which is known to account for both resistance to pathogens and host tissue injury. Although exacerbated inflammation was not observed in ArtinM-treated animals, assessment of neutrophil responses to ArtinM is required to envisage its possible application to design a novel immunomodulatory agent based on carbohydrate recognition. Herein, we focus on the mechanisms through which neutrophils contribute to ArtinM-induced protection against Leishmania, without exacerbating inflammation. For this purpose, human neutrophils treated with ArtinM and infected with Leishmania major were analyzed together with untreated and uninfected controls, based on their ability to eliminate the parasite, release cytokines, degranulate, produce reactive oxygen species (ROS), form neutrophil extracellular traps (NETs) and change life span. We demonstrate that ArtinM-stimulated neutrophils enhanced L. major clearance and at least duplicated tumor necrosis factor (TNF) and interleukin-1beta (IL-1β) release; otherwise, transforming growth factor-beta (TGF-β) production was reduced by half. Furthermore, ROS production and cell degranulation were augmented. The life span of ArtinM-stimulated neutrophils decreased and they did not form NETs when infected with L. major. We postulate that the enhanced leishmanicidal ability of ArtinM-stimulated neutrophils is due to augmented release of inflammatory cytokines, ROS production, and cell degranulation, whereas host tissue integrity is favored by their shortened life span and the absence of NET formation. Our results reinforce the idea that ArtinM may be considered an

  7. Neutrophils Contribute to the Protection Conferred by ArtinM against Intracellular Pathogens: A Study on Leishmania major.

    PubMed

    Ricci-Azevedo, Rafael; Oliveira, Aline Ferreira; Conrado, Marina C A V; Carvalho, Fernanda Caroline; Roque-Barreira, Maria Cristina

    2016-04-01

    ArtinM, a D-mannose binding lectin from Artocarpus heterophyllus, has immunomodulatory activities through its interaction with N-glycans of immune cells, culminating with the establishment of T helper type 1 (Th1) immunity. This interaction protects mice against intracellular pathogens, including Leishmania major and Leishmania amazonensis. ArtinM induces neutrophils activation, which is known to account for both resistance to pathogens and host tissue injury. Although exacerbated inflammation was not observed in ArtinM-treated animals, assessment of neutrophil responses to ArtinM is required to envisage its possible application to design a novel immunomodulatory agent based on carbohydrate recognition. Herein, we focus on the mechanisms through which neutrophils contribute to ArtinM-induced protection against Leishmania, without exacerbating inflammation. For this purpose, human neutrophils treated with ArtinM and infected with Leishmania major were analyzed together with untreated and uninfected controls, based on their ability to eliminate the parasite, release cytokines, degranulate, produce reactive oxygen species (ROS), form neutrophil extracellular traps (NETs) and change life span. We demonstrate that ArtinM-stimulated neutrophils enhanced L. major clearance and at least duplicated tumor necrosis factor (TNF) and interleukin-1beta (IL-1β) release; otherwise, transforming growth factor-beta (TGF-β) production was reduced by half. Furthermore, ROS production and cell degranulation were augmented. The life span of ArtinM-stimulated neutrophils decreased and they did not form NETs when infected with L. major. We postulate that the enhanced leishmanicidal ability of ArtinM-stimulated neutrophils is due to augmented release of inflammatory cytokines, ROS production, and cell degranulation, whereas host tissue integrity is favored by their shortened life span and the absence of NET formation. Our results reinforce the idea that ArtinM may be considered an

  8. The Salmonella Typhimurium effector protein SopE transiently localizes to the early SCV and contributes to intracellular replication.

    PubMed

    Vonaesch, Pascale; Sellin, Mikael E; Cardini, Steven; Singh, Vikash; Barthel, Manja; Hardt, Wolf-Dietrich

    2014-12-01

    Salmonella enterica serovar Typhimurium (S. Tm) is a facultative intracellular pathogen that induces entry into non-phagocytic cells by a Type III secretion system (TTSS) and cognate effector proteins. Upon host cell entry, S. Tm expresses a second TTSS and subverts intracellular trafficking to create a replicative niche - the Salmonella-containing vacuole (SCV). SopE, a guanidyl exchange factor (GEF) for Rac1 and Cdc42, is translocated by the TTSS-1 upon host cell contact and promotes entry through triggering of actin-dependent ruffles. After host cell entry, the bulk of SopE undergoes proteasomal degradation. Here we show that a subfraction is however detectable on the nascent SCV membrane up to ∼ 6 h post infection. Membrane localization of SopE and the closely related SopE2 differentially depend on the Rho-GTPase-binding GEF domain, and to some extent involves also the unstructured N-terminus. SopE localizes transiently to the early SCV, dependent on continuous synthesis and secretion by the TTSS-1 during the intracellular state. Mutant strains lacking SopE or SopE2 are attenuated in early intracellular replication, while complementation restores this defect. Hence, the present study reveals an unanticipated role for SopE and SopE2 in establishing the Salmonella replicative niche, and further emphasizes the importance of entry effectors in later stages of host-cell manipulation.

  9. Biphasic modulation by mGlu5 receptors of TRPV1-mediated intracellular calcium elevation in sensory neurons contributes to heat sensitivity

    PubMed Central

    Masuoka, T; Nakamura, T; Kudo, M; Yoshida, J; Takaoka, Y; Kato, N; Ishibashi, T; Imaizumi, N; Nishio, M

    2015-01-01

    Background and Purpose Elevation of glutamate, an excitatory amino acid, during inflammation and injury plays a crucial role in the reception and transmission of sensory information via ionotropic and metabotropic receptors. This study aimed to investigate the mechanisms underlying the biphasic effects of metabotropic glutamate mGlu5 receptor activation on responses to noxious heat. Experimental Approach We assessed the effects of intraplantar quisqualate, a non-selective glutamate receptor agonist, on heat and mechanical pain behaviours in mice. In addition, the effects of quisqualate on the intracellular calcium response and on membrane currents mediated by TRPV1 channels, were examined in cultured dorsal root ganglion neurons from mice. Key Results Activation of mGlu5 receptors in hind paw transiently increased, then decreased, the response to noxious heat. In sensory neurons, activation of mGlu5 receptors potentiated TRPV1-mediated intracellular calcium elevation, while terminating activation of mGlu5 receptors depressed it. TRPV1-induced currents were potentiated by activation of mGlu5 receptors under voltage clamp conditions and these disappeared after washout. However, voltage-gated calcium currents were inhibited by the mGlu5 receptor agonist, even after washout. Conclusions and Implications These results suggest that, in sensory neurons, mGlu5 receptors biphasically modulate TRPV1-mediated intracellular calcium response via transient potentiation of TRPV1 channel-induced currents and persistent inhibition of voltage-gated calcium currents, contributing to heat hyper- and hypoalgesia. PMID:25297838

  10. Examination of the Staphylococcus aureus nitric oxide reductase (saNOR) reveals its contribution to modulating intracellular NO levels and cellular respiration.

    PubMed

    Lewis, A M; Matzdorf, S S; Endres, J L; Windham, I H; Bayles, K W; Rice, K C

    2015-05-01

    Staphylococcus aureus nitrosative stress resistance is due in part to flavohemoprotein (Hmp). Although hmp is present in all sequenced S. aureus genomes, 37% of analyzed strains also contain nor, encoding a predicted quinol-type nitric oxide (NO) reductase (saNOR). DAF-FM staining of NO-challenged wild-type, nor, hmp and nor hmp mutant biofilms suggested that Hmp may have a greater contribution to intracellular NO detoxification relative to saNOR. However, saNOR still had a significant impact on intracellular NO levels and complemented NO detoxification in a nor hmp mutant. When grown as NO-challenged static (low-oxygen) cultures, hmp and nor hmp mutants both experienced a delay in growth initiation, whereas the nor mutant's ability to initiate growth was comparable with the wild-type strain. However, saNOR contributed to cell respiration in this assay once growth had resumed, as determined by membrane potential and respiratory activity assays. Expression of nor was upregulated during low-oxygen growth and dependent on SrrAB, a two-component system that regulates expression of respiration and nitrosative stress resistance genes. High-level nor promoter activity was also detectable in a cell subpopulation near the biofilm substratum. These results suggest that saNOR contributes to NO-dependent respiration during nitrosative stress, possibly conferring an advantage to nor+ strains in vivo. PMID:25651868

  11. Examination of the Staphylococcus aureus Nitric Oxide Reductase (saNOR) Reveals its Contribution to Modulating Intracellular NO Levels and Cellular Respiration

    PubMed Central

    Lewis, A. M.; Matzdorf, S.S.; Endres, J. L.; Windham, I.H.; Bayles, K. W.; Rice, K. C.

    2015-01-01

    Staphylococcus aureus nitrosative stress resistance is due in part to flavohemoprotein (Hmp). Although hmp is present in all sequenced S. aureus genomes, 37% of analyzed strains also contain nor, encoding a predicted quinol-type NO reductase (saNOR). DAF-FM staining of NO-challenged wild-type, nor, hmp, and nor hmp mutant biofilms suggested that Hmp may have a greater contribution to intracellular NO detoxification relative to saNOR. However, saNOR still had a significant impact on intracellular NO levels, and complemented NO detoxification in a nor hmp mutant. When grown as NO-challenged static (low-oxygen) cultures, hmp and nor hmp mutants both experienced a delay in growth initiation, whereas the nor mutant's ability to initiate growth was comparable to the wild-type strain. However, saNOR contributed to cell respiration in this assay once growth had resumed, as determined by membrane potential and respiratory activity assays. Expression of nor was upregulated during low-oxygen growth and dependent on SrrAB, a two-component system that regulates expression of respiration and nitrosative stress resistance genes. High-level nor promoter activity was also detectable in a cell subpopulation near the biofilm substratum. These results suggest that saNOR contributes to NO-dependent respiration during nitrosative stress, possibly conferring an advantage to nor+ strains in vivo. PMID:25651868

  12. Selective autophagy against membranous compartments

    PubMed Central

    Pimentel-Muiños, Felipe X; Boada-Romero, Emilio

    2014-01-01

    Selective autophagic degradation of cellular components underlies many of the important physiological and pathological implications that autophagy has for mammalian cells. Cytoplasmic vesicles, just like other intracellular items, can be subjected to conventional autophagic events where double-membrane autophagosomes specifically isolate and deliver them for lysosomal destruction. However, intracellular membranes appear to constitute common platforms for unconventional versions of the autophagic pathway, a notion that has become apparent during the past few years. For instance, in many cases of autophagy directed against bacterial phagosomes, subversion of the process results in multimembrane vacuoles that promote bacterial replication instead of the usual degradative outcome. In a different atypical modality, single-membrane vesicles can be labeled with LC3 to direct their contents for lysosomal degradation. In fact, single-membrane compartments of various kinds often provide an assembly site for the autophagic machinery to perform unanticipated nondegradative activities that range from localized secretion of lysosomal contents to melanosome function. Interestingly, many of these unconventional processes seem to be initiated through engagement of relevant nodes of the autophagic signaling network that, once activated, promote LC3 decoration of the targeted membrane, and some cases of inducer/receptor proteins that specifically engage those important signaling hubs have recently been described. Here we review the available examples of all autophagic variants involving membranous compartments, with a main focus on the more recently discovered unconventional phenomena where the usual degradation purpose of autophagy or its canonical mechanistic features are not completely conserved. PMID:24419294

  13. Reduced stability and intracellular transport of dsRNA contribute to poor RNAi response in lepidopteran insects.

    PubMed

    Shukla, Jayendra Nath; Kalsi, Megha; Sethi, Amit; Narva, Kenneth E; Fishilevich, Elane; Singh, Satnam; Mogilicherla, Kanakachari; Palli, Subba Reddy

    2016-07-01

    RNA interference (RNAi) has become a widely used reverse genetic tool to study gene function in eukaryotic organisms and is being developed as a technology for insect pest management. The efficiency of RNAi varies among organisms. Insects from different orders also display differential efficiency of RNAi, ranging from highly efficient (coleopterans) to very low efficient (lepidopterans). We investigated the reasons for varying RNAi efficiency between lepidopteran and coleopteran cell lines and also between the Colorado potato beetle, Leptinotarsa decemlineata and tobacco budworm, Heliothis virescens. The dsRNA either injected or fed was degraded faster in H. virescens than in L. decemlineata. Both lepidopteran and coleopteran cell lines and tissues efficiently took up the dsRNA. Interestingly, the dsRNA administered to coleopteran cell lines and tissues was taken up and processed to siRNA whereas the dsRNA was taken up by lepidopteran cell lines and tissues but no siRNA was detected in the total RNA isolated from these cell lines and tissues. The data included in this paper showed that the degradation and intracellular transport of dsRNA are the major factors responsible for reduced RNAi efficiency in lepidopteran insects. PMID:27245473

  14. Reduced stability and intracellular transport of dsRNA contribute to poor RNAi response in lepidopteran insects

    PubMed Central

    Shukla, Jayendra Nath; Kalsi, Megha; Sethi, Amit; Narva, Kenneth E.; Fishilevich, Elane; Singh, Satnam; Mogilicherla, Kanakachari; Palli, Subba Reddy

    2016-01-01

    ABSTRACT RNA interference (RNAi) has become a widely used reverse genetic tool to study gene function in eukaryotic organisms and is being developed as a technology for insect pest management. The efficiency of RNAi varies among organisms. Insects from different orders also display differential efficiency of RNAi, ranging from highly efficient (coleopterans) to very low efficient (lepidopterans). We investigated the reasons for varying RNAi efficiency between lepidopteran and coleopteran cell lines and also between the Colorado potato beetle, Leptinotarsa decemlineata and tobacco budworm, Heliothis virescens. The dsRNA either injected or fed was degraded faster in H. virescens than in L. decemlineata. Both lepidopteran and coleopteran cell lines and tissues efficiently took up the dsRNA. Interestingly, the dsRNA administered to coleopteran cell lines and tissues was taken up and processed to siRNA whereas the dsRNA was taken up by lepidopteran cell lines and tissues but no siRNA was detected in the total RNA isolated from these cell lines and tissues. The data included in this paper showed that the degradation and intracellular transport of dsRNA are the major factors responsible for reduced RNAi efficiency in lepidopteran insects. PMID:27245473

  15. Compartmented electrode structure

    DOEpatents

    Vissers, Donald R.; Shimotake, Hiroshi; Gay, Eddie C.; Martino, Fredric J.

    1977-06-14

    Electrodes for secondary electrochemical cells are provided with compartments for containing particles of the electrode reactant. The compartments are defined by partitions that are generally impenetrable to the particles of reactant and, in some instances, to the liquid electrolyte used in the cell. During cycling of the cell, reactant material initially loaded into a particular compartment is prevented from migrating and concentrating within the lower portion of the electrode or those portions of the electrode that exhibit reduced electrical resistance.

  16. Contribution of sarcolemmal sodium-calcium exchange and intracellular calcium release to force development in isolated canine ventricular muscle

    PubMed Central

    1992-01-01

    frequency in 70 mM [Na+]o was not a consequence of a decreased rate of refilling of a releasable pool of Ca2+ within the cell. These results demonstrate that frequency-dependent changes of contractile strength and intracellular Ca2+ loading in 140 mM [Na+]o require the presence of a functional sarcolemmal Na(+)-Ca2+ exchange process. The possibility that the negative staircase in 70 mM [Na+]o is related to inhibition of Ca(2+)-induced release of Ca2+ from the SR by various cellular mechanisms is discussed. PMID:1640221

  17. Intracellular Ca2+ release through ryanodine receptors contributes to AMPA receptor-mediated mitochondrial dysfunction and ER stress in oligodendrocytes

    PubMed Central

    Ruiz, A; Matute, C; Alberdi, E

    2010-01-01

    Overactivation of ionotropic glutamate receptors in oligodendrocytes induces cytosolic Ca2+ overload and excitotoxic death, a process that contributes to demyelination and multiple sclerosis. Excitotoxic insults cause well-characterized mitochondrial alterations and endoplasmic reticulum (ER) dysfunction, which is not fully understood. In this study, we analyzed the contribution of ER-Ca2+ release through ryanodine receptors (RyRs) and inositol triphosphate receptors (IP3Rs) to excitotoxicity in oligodendrocytes in vitro. First, we observed that oligodendrocytes express all previously characterized RyRs and IP3Rs. Blockade of Ca2+-induced Ca2+ release by TMB-8 following α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) receptor-mediated insults attenuated both oligodendrocyte death and cytosolic Ca2+ overload. In turn, RyR inhibition by ryanodine reduced as well the Ca2+ overload whereas IP3R inhibition was ineffective. Furthermore, AMPA-triggered mitochondrial membrane depolarization, oxidative stress and activation of caspase-3, which in all instances was diminished by RyR inhibition. In addition, we observed that AMPA induced an ER stress response as revealed by α subunit of the eukaryotic initiation factor 2α phosphorylation, overexpression of GRP chaperones and RyR-dependent cleavage of caspase-12. Finally, attenuating ER stress with salubrinal protected oligodendrocytes from AMPA excitotoxicity. Together, these results show that Ca2+ release through RyRs contributes to cytosolic Ca2+ overload, mitochondrial dysfunction, ER stress and cell death following AMPA receptor-mediated excitotoxicity in oligodendrocytes. PMID:21364659

  18. N-Acetylated alpha-linked acidic dipeptidase expressed in rat adipocytes is localized in the insulin-responsive glucose transporter (GLUT4) intracellular compartments and involved in the insulin-stimulated GLUT4 recruitment.

    PubMed

    Park, Seung Y; Ha, Byoung G; Choi, Geum H; Lee, Wan

    2004-04-01

    The GLUT4-containing vesicles purified from rat adipocyte contain many protein species of unknown identity, some of which are likely to play a critical role in the trafficking of GLUT4. Presently, we describe an 85-kDa protein in GLUT4-vesicles of rat adipocytes as a potential GLUT4 traffic regulatory protein. MALDI-TOF MS, RT-PCR, gene cloning, protein sequence analysis, and immunoreactivity assay have identified this protein as N-acetylated alpha-linked acidic dipeptidase (NAALADase) expressed in rat adipocytes. NAALADase in rat adipocytes was mostly membrane-associated and colocalized in discrete GLUT4-compartments with enrichment in putative GLUT4-sorting endosomes (G4G(L)). Total cell lysates of adipocytes exhibited NAALADase activity. Next, we treated rat adipocytes with 2-[phosphonomethy]pentanedionic acid (2-PMPA), a potent NAALADase inhibitor, and studied its effect on the distribution of GLUT4 and 3-O-methyl glucose (3OMG) flux. In 2-PMPA-treated adipocytes, there was a significant reduction (by 40%) in the insulin-stimulated GLUT4 translocation to the plasma membrane. The 3OMG flux in insulin-stimulated adipocytes was also delayed (51% of control) by 2-PMPA treatment, indicating that 2-PMPA impairs insulin-stimulated GLUT4 recruitment and the uptake of glucose. It is suggested that NAALADase may function as a regulator required for the insulin-stimulated GLUT4 vesicle movement and/or its exocytosis, thus may regulate insulin-induced GLUT4 recruitment in rat adipocytes.

  19. Enhanced Ca(2+)-induced Ca(2+) release from intracellular stores contributes to catecholamine hypersecretion in adrenal chromaffin cells from spontaneously hypertensive rats.

    PubMed

    Segura-Chama, Pedro; López-Bistrain, Patricia; Pérez-Armendáriz, Elia Martha; Jiménez-Pérez, Nicolás; Millán-Aldaco, Diana; Hernández-Cruz, Arturo

    2015-11-01

    Adrenal chromaffin cells (CCs) from spontaneously hypertensive rats (SHRs) secrete more catecholamine (CA) upon stimulation than CCs from normotensive Wistar Kyoto rats (WKY). Unitary CA exocytosis events, both spontaneous and stimulated, were amperometrically recorded from cultured WKY and SHR CCs. Both strains display spontaneous amperometric spikes but SHR CCs produce more spikes and of higher mean amplitude. After a brief stimulation with high K(+) or caffeine which produces voltage-gated Ca(2+) influx or intracellular Ca(2+) release, respectively, more spikes and of greater mean amplitude and unitary charge were recorded in SHR CCs. Consequently, peak cumulative charge was ~2-fold higher in SHR CCs. Ryanodine (10 μM), a specific blocker of the ryanodine receptors reduced depolarization-induced peak cumulative charge by ~10 % in WKY and ~77 % in SHR CCs, suggesting, a larger contribution of Ca(2+)-induced Ca(2+) release to CA exocytosis in SHR CCs. Accordingly, Ca(2+) imaging showed larger [Ca(2+)]i signals induced both by depolarization and caffeine in SHR CCs. Distribution amplitude histograms showed that small amperometric spikes (0-50 pA) are more frequent in WKY than in SHR CCs. Conversely, medium (50-190 pA) and large (190-290 pA) spikes are more numerous in SHR than in WKY CCs. This study reveals that the enhanced CA secretion in SHR CCs results from a combination of (1) larger depolarization-induced Ca(2+) transients, due to a greater Ca(2+)-induced intracellular Ca(2+) release, (2) more exocytosis events per time unit, and (3) a greater proportion of medium and large amperometric spikes probably due to a higher mean CA content per granule. Enhanced CA release by excessive amplification by Ca(2+) induced Ca(2+) release and larger granule catecholamine content contributes to the increased CA plasma levels and vasomotor tone in SHRs. PMID:25791627

  20. Single compartment drug delivery

    PubMed Central

    Cima, Michael J.; Lee, Heejin; Daniel, Karen; Tanenbaum, Laura M.; Mantzavinou, Aikaterini; Spencer, Kevin C.; Ong, Qunya; Sy, Jay C.; Santini, John; Schoellhammer, Carl M.; Blankschtein, Daniel; Langer, Robert S.

    2014-01-01

    Drug design is built on the concept that key molecular targets of disease are isolated in the diseased tissue. Systemic drug administration would be sufficient for targeting in such a case. It is, however, common for enzymes or receptors that are integral to disease to be structurally similar or identical to those that play important biological roles in normal tissues of the body. Additionally, systemic administration may not lead to local drug concentrations high enough to yield disease modification because of rapid systemic metabolism or lack of sufficient partitioning into the diseased tissue compartment. This review focuses on drug delivery methods that physically target drugs to individual compartments of the body. Compartments such as the bladder, peritoneum, brain, eye and skin are often sites of disease and can sometimes be viewed as “privileged,” since they intrinsically hinder partitioning of systemically administered agents. These compartments have become the focus of a wide array of procedures and devices for direct administration of drugs. We discuss the rationale behind single compartment drug delivery for each of these compartments, and give an overview of examples at different development stages, from the lab bench to phase III clinical trials to clinical practice. We approach single compartment drug delivery from both a translational and a technological perspective. PMID:24798478

  1. Intracellular redistribution of SCP2 in Leydig cells after hormonal stimulation may contribute to increased pregnenolone production.

    PubMed

    van Noort, M; Rommerts, F F; van Amerongen, A; Wirtz, K W

    1988-07-15

    Sterol carrier protein2 (SCP2) also designated non specific lipid transfer protein (nsL-TP), added to tumour Leydig cell mitochondria as a pure compound or in cytosolic preparations, stimulates pregnenolone production two- to three-fold. This stimulation can be abolished by addition of anti rat SCP2 but not by preimmune IgG-antibodies. SCP2- levels in the cytosol are increased in less than two minutes after addition of lutropin (LH). This increased SCP2 level may contribute to stimulation of steroid production in intact cells. After hormonal stimulation the subcellular distribution of SCP2 changes. A two-fold increase of SCP2- levels in the supernatant fraction and four-fold decrease in extracts of the particulate fraction was observed 30 min after stimulation of tumour Leydig cells with LH and subsequent fractionation. This apparent shift of SCP2 can be explained by an altered association with membranes or a true relocation of the protein from the particulate to the supernatant fractions under the influence of the hormone. PMID:3395346

  2. Acute extremity compartment syndrome.

    PubMed

    Tumbarello, C

    2000-01-01

    Acute Extremity Compartment Syndrome is a disorder, which can cause loss of limb if left untreated. Compartment syndrome develops when pressures within the fascial compartments become elevated, resulting in decreased perfusion to muscles and nerves. Left untreated, tissue death occurs. Rapid identification of clinical signs can decrease severity of symptoms. Diligent nursing assessment and monitoring of clinical signs, with communication to the physician, will facilitate rapid treatment by the physician. The primary treatment option is early identification and intervention through performance of a fasciotomy.

  3. Establishment of subcellular fractionation techniques to monitor the intracellular fate of polymer therapeutics II. Identification of endosomal and lysosomal compartments in HepG2 cells combining single-step subcellular fractionation with fluorescent imaging.

    PubMed

    Manunta, Maria; Izzo, Lorella; Duncan, Ruth; Jones, Arwyn Tomos

    2007-01-01

    As they are often designed for lysosomotropic, endosomotropic and/or transcellular delivery, an understanding of intracellular trafficking pathways is essential to enable optimised design of novel polymer therapeutics. Here, we describe a single-step density gradient subcellular fractionation method combined with fluorescent detection analysis that provides a new tool for characterisation of endocytic traffic of polymer therapeutics. Hepatoma (HepG2) cells were used as a model and cell breakage was optimised using a cell cracker to ensure assay of the whole cell population. After removal of unbroken cells and nuclei, the cell lysate as a post-nuclear supernatant (PNS) was layered onto an iodixanol (OptiPrep) density gradient optimised to 5-20%. Early endosomes, late endosomes and lysosomes were identified from gradient fractions by immunoblotting for marker proteins early endosome antigen 1 (EEA 1) and lysosomal associated membrane protein 1 (LAMP 1) using horseradish peroxidase or fluorescently-labelled secondary antibodies. Lysosomes were also detected using N-acetyl-beta-glucosamindase (Hex A) activity. In addition, cells were incubated with Texas-red labelled transferrin (TxR-Tf) for 5 min to specifically label early endosomes and this was directly detected from SDS-PAGE gels. Internalised macromolecules and colloidal particles can potentially alter vesicle buoyant density. To see if typical macromolecules of interest would alter vesicle density or perturb vesicle traffic, HepG2 cells were incubated with dextran or a polyethyleneglycol (PEG)-polyester dendron G4 (1 mg/ml for 24 h). The PEG-polyester dendron G4 caused a slight redistribution of endocytic structures to lower density fractions but immunofluorescence microscopy showed no obvious dendron effects. In conclusion, the combined subcellular fractionation with fluorescent imaging approach described here can be used as a tool for both fundamental cell biology research and/or the quantitative localisation

  4. Chronic Exertional Compartment Syndrome.

    PubMed

    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.

  5. A Distinctive Cytoplasmic Tail Contributes to Low Surface Expression and Intracellular Retention of the Patr-AL MHC class I molecule1

    PubMed Central

    Goyos, Ana; Guethlein, Lisbeth A.; Horowitz, Amir; Hilton, Hugo G.; Gleimer, Michael; Brodsky, Frances M.; Parham, Peter

    2015-01-01

    Chimpanzees have orthologs of the six, fixed, functional human MHC class I genes. But in addition, the chimpanzee has a seventh functional gene, Patr-AL, which is not polymorphic but contributes substantially to population diversity by its presence on only 50% of MHC haplotypes. The ancestral AL gene emerged long before the separation of human and chimpanzee ancestors and then subsequently and specifically lost function during human evolution, but was maintained in chimpanzees. Patr-AL is an alloantigen that participates in negative and positive selection of the T-cell repertoire. The three-dimensional structure and the peptide-binding repertoire of Patr-AL and HLA-A*02 are surprisingly similar. In contrast, the expression of these two molecules is very different as shown using specific monoclonal and polyclonal antibodies made against Patr-AL. Peripheral blood cells and B cell lines express low levels of Patr-AL at the cell surface. Higher levels are seen for 221-cell transfectants expressing Patr-AL, but in these cells a large majority of Patr-AL molecules are retained in the early compartments of the secretory pathway: mainly the endoplasmic reticulum but also cis-Golgi. Replacing the cytoplasmic tail of Patr-AL with that of HLA-A*02 increased the cell-surface expression of Patr-AL substantially. Four substitutions distinguish the Patr-AL and HLA-A*02 cytoplasmic tails. Systematic mutagenesis showed that each substitution contributes changes in cell-surface expression. The combination of residues present in Patr-AL appears unique, but each individual residue is present in other primate MHC class I molecules, notably MHC-E, the most ancient of the functional human MHC class I molecules. PMID:26371256

  6. Contribution of local thyroxine monodeiodination to intracellular 3,5, 3'-triiodothyronine in several tissues of hyperthyroid rats at isotopic equilibrium

    SciTech Connect

    van Doorn, J.; van der Heide, D.; Roelfsema, F.

    1984-07-01

    The local conversion of T4 as a source of intracellular T3 in several organs of both hypothyroid and euthyroid rats has recently been recognized to be an important phenomenon. In the present study the source and quantity of T3 in various peripheral tissues of hyperthyroid rats were investigated. Athyreotic rats received a continuous iv infusion of T4 over a prolonged period in order to attain hyperthyroid conditions. At the same time, the animals also received a continuous iv infusion of (/sup 125/I)T4 and (/sup 131/I)T3 until isotopic equilibrium was achieved. After the animals were bled and perfused, the source and quantity of T3 in various tissue homogenates and subcellular preparations of liver, kidney, and the anterior pituitary gland were analyzed. In spite of the elevated plasma T3 and T4 levels, the concentration of T3 in the cerebral cortex and cerebellum was within the normal range. The contribution of T3 derived from local T4 to T3 conversion (Lc T3(T4)) was rather low in both parts of the brain when compared with values previously determined for euthyroid rats. Whereas previous studies revealed that Lc T3(T4) contributes significantly to the T3 in the pituitary glands of both hypothyroid and euthyroid rats, this was not the case for the hyperthyroid animals; virtually all T3 was derived from plasma. It was found that the T3 in muscle was derived exclusively from plasma. Both the liver and kidney showed high concentrations of T3. Whereas Lc T3(T4) was the main source of T3 in the liver, it contributed only a minor fraction of the total T3 content in the kidney.

  7. Intracellular shunting of O2− contributes to charge compensation and preservation of neutrophil respiratory burst in the absence of voltage-gated proton channel activity

    PubMed Central

    Decleva, Eva; Menegazzi, Renzo; Fasolo, Alba; Defendi, Federica; Sebastianutto, Michele; Dri, Pietro

    2013-01-01

    Proton efflux via voltage-gated proton channels (Hv1) is considered to mediate the charge compensation necessary to preserve NADPH oxidase activity during the respiratory burst. Using the Hv1 inhibitor Zn2+, we found that the PMA-induced respiratory burst of human neutrophils is inhibited when assessed as extracellular production of O2− and H2O2, in accordance with literature studies, but, surprisingly, unaffected when measured as oxygen consumption or total (extracellular plus intracellular) H2O2 production. Furthermore, we show that inhibiting Hv1 with Zn2+ results in an increased production of intracellular ROS. Similar results, i.e. decreased extracellular and increased intracellular ROS production, were obtained using a human granulocyte-like cell line with severely impaired Hv1 expression. Acidic extracellular pH, which dampens proton efflux, also augmented intracellular production of H2O2. Zinc caused an increase in the rate but not in the extent of depolarization and cytosolic acidification indicating that mechanisms other than proton efflux take part in charge compensation. Our results suggest a hitherto unpredicted mechanism of charge compensation whereby, in the absence of proton efflux, part of O2− generated within gp91phox in the plasma membrane is shunted intracellularly down electrochemical gradient to dampen excessive depolarization. This would preserve NADPH oxidase activity under conditions such as the inflammatory exudate in which the acidic pH hinders charge compensation by proton efflux. PMID:23578765

  8. Mathematical Model for the Contribution of Individual Organs to Non-Zero Y-Intercepts in Single and Multi-Compartment Linear Models of Whole-Body Energy Expenditure

    PubMed Central

    Kaiyala, Karl J.

    2014-01-01

    Mathematical models for the dependence of energy expenditure (EE) on body mass and composition are essential tools in metabolic phenotyping. EE scales over broad ranges of body mass as a non-linear allometric function. When considered within restricted ranges of body mass, however, allometric EE curves exhibit ‘local linearity.’ Indeed, modern EE analysis makes extensive use of linear models. Such models typically involve one or two body mass compartments (e.g., fat free mass and fat mass). Importantly, linear EE models typically involve a non-zero (usually positive) y-intercept term of uncertain origin, a recurring theme in discussions of EE analysis and a source of confounding in traditional ratio-based EE normalization. Emerging linear model approaches quantify whole-body resting EE (REE) in terms of individual organ masses (e.g., liver, kidneys, heart, brain). Proponents of individual organ REE modeling hypothesize that multi-organ linear models may eliminate non-zero y-intercepts. This could have advantages in adjusting REE for body mass and composition. Studies reveal that individual organ REE is an allometric function of total body mass. I exploit first-order Taylor linearization of individual organ REEs to model the manner in which individual organs contribute to whole-body REE and to the non-zero y-intercept in linear REE models. The model predicts that REE analysis at the individual organ-tissue level will not eliminate intercept terms. I demonstrate that the parameters of a linear EE equation can be transformed into the parameters of the underlying ‘latent’ allometric equation. This permits estimates of the allometric scaling of EE in a diverse variety of physiological states that are not represented in the allometric EE literature but are well represented by published linear EE analyses. PMID:25068692

  9. Exertional compartment syndrome of the upper extremity.

    PubMed

    Botte, M J; Fronek, J; Pedowitz, R A; Hoenecke, H R; Abrams, R A; Hamer, M L

    1998-08-01

    Exertional compartment syndrome is characterized by intracompartmental pressures that rise transiently following repetitive motion or exercise, thereby producing temporary, reversible ischemia, pain, weakness, and, occasionally, neurologic deficits. The exact cause or pathogenesis remains unclear; a disturbance of microvascular flow caused by elevated intramuscular pressure leads to tissue ischemia, depletion of high-energy phosphate stores, and cellular acidosis. Anatomic contributing factors may include a limited compartment size, increased intracompartmental volume, constricted fascia, loss of compartment elasticity, poor venous return, or increased muscle bulk. The diagnosis is suspected based on history and confirmed with physical examination and intramuscular pressure evaluation before and after exercise (stress test). Differential diagnosis includes claudication or other vascular abnormalities, myositis, tendinitis, periostitis, chronic strains or sprains, stress fracture, other compression or systemic neuropathies, and cardiac abnormalities with angina or referred extremity pain. Initial treatment includes activity modification; refractory symptoms can be managed with elective fasciotomy.

  10. Nanovehicular Intracellular Delivery Systems

    PubMed Central

    PROKOP, ALES; DAVIDSON, JEFFREY M.

    2013-01-01

    This article provides an overview of principles and barriers relevant to intracellular drug and gene transport, accumulation and retention (collectively called as drug delivery) by means of nanovehicles (NV). The aim is to deliver a cargo to a particular intracellular site, if possible, to exert a local action. Some of the principles discussed in this article apply to noncolloidal drugs that are not permeable to the plasma membrane or to the blood–brain barrier. NV are defined as a wide range of nanosized particles leading to colloidal objects which are capable of entering cells and tissues and delivering a cargo intracelullarly. Different localization and targeting means are discussed. Limited discussion on pharmacokinetics and pharmacodynamics is also presented. NVs are contrasted to micro-delivery and current nanotechnologies which are already in commercial use. Newer developments in NV technologies are outlined and future applications are stressed. We also briefly review the existing modeling tools and approaches to quantitatively describe the behavior of targeted NV within the vascular and tumor compartments, an area of particular importance. While we list “elementary” phenomena related to different level of complexity of delivery to cancer, we also stress importance of multi-scale modeling and bottom-up systems biology approach. PMID:18200527

  11. Regulation of intracellular heme trafficking revealed by subcellular reporters.

    PubMed

    Yuan, Xiaojing; Rietzschel, Nicole; Kwon, Hanna; Walter Nuno, Ana Beatriz; Hanna, David A; Phillips, John D; Raven, Emma L; Reddi, Amit R; Hamza, Iqbal

    2016-08-30

    Heme is an essential prosthetic group in proteins that reside in virtually every subcellular compartment performing diverse biological functions. Irrespective of whether heme is synthesized in the mitochondria or imported from the environment, this hydrophobic and potentially toxic metalloporphyrin has to be trafficked across membrane barriers, a concept heretofore poorly understood. Here we show, using subcellular-targeted, genetically encoded hemoprotein peroxidase reporters, that both extracellular and endogenous heme contribute to cellular labile heme and that extracellular heme can be transported and used in toto by hemoproteins in all six subcellular compartments examined. The reporters are robust, show large signal-to-background ratio, and provide sufficient range to detect changes in intracellular labile heme. Restoration of reporter activity by heme is organelle-specific, with the Golgi and endoplasmic reticulum being important sites for both exogenous and endogenous heme trafficking. Expression of peroxidase reporters in Caenorhabditis elegans shows that environmental heme influences labile heme in a tissue-dependent manner; reporter activity in the intestine shows a linear increase compared with muscle or hypodermis, with the lowest heme threshold in neurons. Our results demonstrate that the trafficking pathways for exogenous and endogenous heme are distinct, with intrinsic preference for specific subcellular compartments. We anticipate our results will serve as a heuristic paradigm for more sophisticated studies on heme trafficking in cellular and whole-animal models.

  12. Regulation of intracellular heme trafficking revealed by subcellular reporters.

    PubMed

    Yuan, Xiaojing; Rietzschel, Nicole; Kwon, Hanna; Walter Nuno, Ana Beatriz; Hanna, David A; Phillips, John D; Raven, Emma L; Reddi, Amit R; Hamza, Iqbal

    2016-08-30

    Heme is an essential prosthetic group in proteins that reside in virtually every subcellular compartment performing diverse biological functions. Irrespective of whether heme is synthesized in the mitochondria or imported from the environment, this hydrophobic and potentially toxic metalloporphyrin has to be trafficked across membrane barriers, a concept heretofore poorly understood. Here we show, using subcellular-targeted, genetically encoded hemoprotein peroxidase reporters, that both extracellular and endogenous heme contribute to cellular labile heme and that extracellular heme can be transported and used in toto by hemoproteins in all six subcellular compartments examined. The reporters are robust, show large signal-to-background ratio, and provide sufficient range to detect changes in intracellular labile heme. Restoration of reporter activity by heme is organelle-specific, with the Golgi and endoplasmic reticulum being important sites for both exogenous and endogenous heme trafficking. Expression of peroxidase reporters in Caenorhabditis elegans shows that environmental heme influences labile heme in a tissue-dependent manner; reporter activity in the intestine shows a linear increase compared with muscle or hypodermis, with the lowest heme threshold in neurons. Our results demonstrate that the trafficking pathways for exogenous and endogenous heme are distinct, with intrinsic preference for specific subcellular compartments. We anticipate our results will serve as a heuristic paradigm for more sophisticated studies on heme trafficking in cellular and whole-animal models. PMID:27528661

  13. Intracellular shunting of O{sub 2}{sup −} contributes to charge compensation and preservation of neutrophil respiratory burst in the absence of voltage-gated proton channel activity

    SciTech Connect

    Decleva, Eva; Menegazzi, Renzo; Fasolo, Alba; Defendi, Federica

    2013-07-15

    depolarization and pH{sub i} decrease. • Intracellular shunting of O{sub 2}{sup −} contributes to charge compensation in neutrophils.

  14. Acute compartment syndrome in lower extremity musculoskeletal trauma.

    PubMed

    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.

  15. The contribution of both oxygen and nitrogen intermediates to the intracellular killing mechanisms of C1q-opsonized Listeria monocytogenes by the macrophage-like IC-21 cell line.

    PubMed

    Alvarez-Domínguez, C; Carrasco-Marín, E; López-Mato, P; Leyva-Cobián, F

    2000-09-01

    Listeria monocytogenes is a facultative intracellular pathogen which is internalized by host mammalian cells upon binding to their surface. Further listerial growth occurs in the cytosol after escape from the phagosomal-endosomal compartment. We have previously reported that C1q is able to potentiate L. monocytogenes phagocytosis upon bacterial opsonization by ingestion through C1q-binding structures. In this report, we analysed the post-phagocytic events upon internalization of C1q-opsonized L. monocytogenes and found an induction of macrophage (Mphi)-like IC-21 cell bactericidal mechanisms displayed by the production of oxygen and nitrogen metabolites. Both types of molecules are effective in L. monocytogenes killing. Further analysis of the cellular responses promoted by interaction of C1q with its surface binding structures, leads us to consider C1q as a collaborative molecule involved in Mphi activation. Upon interaction with surface binding structures, C1q was able to trigger and/or amplify the production of reactive oxygen and nitrogen intermediates induced by stimuli such as interferon-gamma and L. monocytogenes phagocytosis. PMID:11012757

  16. The contribution of both oxygen and nitrogen intermediates to the intracellular killing mechanisms of C1q-opsonized Listeria monocytogenes by the macrophage-like IC-21 cell line

    PubMed Central

    Álvarez-Domínguez, C; Carrasco-Marín, E; López-Mato, P; Leyva-Cobián, F

    2000-01-01

    Listeria monocytogenes is a facultative intracellular pathogen which is internalized by host mammalian cells upon binding to their surface. Further listerial growth occurs in the cytosol after escape from the phagosomal–endosomal compartment. We have previously reported that C1q is able to potentiate L. monocytogenes phagocytosis upon bacterial opsonization by ingestion through C1q-binding structures. In this report, we analysed the post-phagocytic events upon internalization of C1q-opsonized L. monocytogenes and found an induction of macrophage (Mφ)-like IC-21 cell bactericidal mechanisms displayed by the production of oxygen and nitrogen metabolites. Both types of molecules are effective in L. monocytogenes killing. Further analysis of the cellular responses promoted by interaction of C1q with its surface binding structures, leads us to consider C1q as a collaborative molecule involved in Mφ activation. Upon interaction with surface binding structures, C1q was able to trigger and/or amplify the production of reactive oxygen and nitrogen intermediates induced by stimuli such as interferon-γ and L. monocytogenes phagocytosis. PMID:11012757

  17. LL37:DNA complexes provide antimicrobial activity against intracellular bacteria in human macrophages.

    PubMed

    Stephan, Alexander; Batinica, Marina; Steiger, Julia; Hartmann, Pia; Zaucke, Frank; Bloch, Wilhelm; Fabri, Mario

    2016-08-01

    As part of the innate host response neutrophils release neutrophil extracellular traps (NETs), protein:DNA complexes that contain a number of antimicrobial peptides (AMPs), such as cathelicidin. Human cathelicidin in its active form, LL37, has potent antimicrobial activity against bacteria. However, whether LL37 derived from NETs contributes to antimicrobial activity against intracellular pathogens remains unclear. Here, we report that NETs induced by mycobacteria contain cathelicidin. Human macrophages internalized NET-bound cathelicidin, which is transported to lysosomal compartments. Furthermore, using a model of in vitro-generated LL37:DNA complexes we found that LL37 derived from such complexes attacks mycobacteria in macrophage phagolysosomes resulting in antimicrobial activity. Taken together, our results suggest a mechanism by which LL37 in complex with DNA contributes to host defence against intracellular bacteria in human macrophages.

  18. [Abdominal compartment syndrome].

    PubMed

    Pottecher, T; Segura, P; Launoy, A

    2001-04-01

    French physicians dealing with abdominal emergencies are not very familiar with the abdominal compartment syndrome (ACS). Increased abdominal pressure has deleterious consequences on local (intestine, liver, kidney) circulation, leading to death in the absence of correct treatment. Abdominal trauma and ruptured aortic aneurism are the main causes of ACS. Clinical presentation may be misleading: respiratory failure, oliguria or circulatory symptoms are often predominant. Abdominal palpation is inefficient for evaluating intra-abdominal pressure (IAP); only measurement of cystic pressure allows precise evaluation of IAP. Abdominal decompression is the treatment of choice. It must be performed as soon as IAP exceeds 25 mmHg. The procedure may be risky with a high incidence of severe complications when ischaemic territories are reperfused. Recent data underline the importance of compensation of hypovolemia before decompression. Abdominal closure may necessitate various techniques (aponevrotomy, Bogota bags, etc.). At any rate, IAP must remain low at the end of the procedure. In case of suspicion of ACS, early measurement of IAP is mandatory. If pressure is over 25 mmHg, a decompressive procedure must be initiated. PMID:11340703

  19. COMPARTMENTED REACTOR FUEL ELEMENT

    DOEpatents

    Cain, F.M. Jr.

    1962-09-11

    A method of making a nuclear reactor fuel element of the elongated red type is given wherein the fissionable fuel material is enclosed within a tubular metal cladding. The method comprises coating the metal cladding tube on its inside wall with a brazing alloy, inserting groups of cylindrical pellets of fissionable fuel material into the tube with spacing members between adjacent groups of pellets, sealing the ends of the tubes to leave a void space therewithin, heating the tube and its contents to an elevated temperature to melt the brazing alloy and to expand the pellets to their maximum dimensions under predetermined operating conditions thereby automatically positioning the spacing members along the tube, and finally cooling the tube to room temperature whereby the spacing disks become permanently fixed at their edges in the brazing alloy and define a hermetically sealed compartment for each fl group of fuel pellets. Upon cooling, the pellets contract thus leaving a space to accommodate thermal expansion of the pellets when in use in a reactor. The spacing members also provide lateral support for the tubular cladding to prevent collapse thereof when subjected to a reactor environment. (AEC)

  20. Intracellular Macrophage Infections with E. coli under Nitrosative Stress

    PubMed Central

    Bateman, Stacey L.; Seed, Patrick

    2016-01-01

    Escherichia coli (E. coli) produces disseminated infections of the urinary tract, blood, and central nervous system where it encounters professional phagocytes such as macrophages, which utilize reactive nitrogen intermediates (RNI) to arrest bacteria. In vitro, extraintestinal pathogenic E. coli (ExPEC) can survive within bone marrow-derived macrophages for greater than 24 h post-infection within a LAMP1+ vesicular compartment, and ExPEC strains, in particular, are better adapted to intracellular macrophage survival than commensal strains (Bokil et al., 2011). This protocol details an intracellular murine macrophage-like cell infection, including modulation of the host nitrosative stress response, to model this host-pathogen interaction in vitro. To accomplish this, RAW 264.7 murine macrophage-like cells are pre-incubated with either L-arginine, an NO precursor, or IFNγ to yield a high nitric oxide (NO) physiological state, or L-NAME, an inducible NO synthase (iNOS)-specific inhibitor, to yield a low NO physiological state. This protocol has been successfully utilized to assess the contribution of a novel ExPEC regulator to intracellular survival and the nitrosative stress response during macrophage infections (Bateman and Seed, 2012), but can be adapted for use with a variety of E. coli strains or isogenic deletions.

  1. Activated G Protein Gαs Samples Multiple Endomembrane Compartments.

    PubMed

    Martin, Brent R; Lambert, Nevin A

    2016-09-23

    Heterotrimeric G proteins are localized to the plasma membrane where they transduce extracellular signals to intracellular effectors. G proteins also act at intracellular locations, and can translocate between cellular compartments. For example, Gαs can leave the plasma membrane and move to the cell interior after activation. However, the mechanism of Gαs translocation and its intracellular destination are not known. Here we use bioluminescence resonance energy transfer (BRET) to show that after activation, Gαs rapidly associates with the endoplasmic reticulum, mitochondria, and endosomes, consistent with indiscriminate sampling of intracellular membranes from the cytosol rather than transport via a specific vesicular pathway. The primary source of Gαs for endosomal compartments is constitutive endocytosis rather than activity-dependent internalization. Recycling of Gαs to the plasma membrane is complete 25 min after stimulation is discontinued. We also show that an acylation-deacylation cycle is important for the steady-state localization of Gαs at the plasma membrane, but our results do not support a role for deacylation in activity-dependent Gαs internalization. PMID:27528603

  2. Simplest relationship between local field potential and intracellular signals in layered neural tissue

    NASA Astrophysics Data System (ADS)

    Chizhov, Anton V.; Sanchez-Aguilera, Alberto; Rodrigues, Serafim; de la Prida, Liset Menendez

    2015-12-01

    The relationship between the extracellularly measured electric field potential resulting from synaptic activity in an ensemble of neurons and intracellular signals in these neurons is an important but still open question. Based on a model neuron with a cylindrical dendrite and lumped soma, we derive a formula that substantiates a proportionality between the local field potential and the total somatic transmembrane current that emerges from the difference between the somatic and dendritic membrane potentials. The formula is tested by intra- and extracellular recordings of evoked synaptic responses in hippocampal slices. Additionally, the contribution of different membrane currents to the field potential is demonstrated in a two-population mean-field model. Our formalism, which allows for a simple estimation of unknown dendritic currents directly from somatic measurements, provides an interpretation of the local field potential in terms of intracellularly measurable synaptic signals. It is also applicable to the study of cortical activity using two-compartment neuronal population models.

  3. Simplest relationship between local field potential and intracellular signals in layered neural tissue.

    PubMed

    Chizhov, Anton V; Sanchez-Aguilera, Alberto; Rodrigues, Serafim; de la Prida, Liset Menendez

    2015-12-01

    The relationship between the extracellularly measured electric field potential resulting from synaptic activity in an ensemble of neurons and intracellular signals in these neurons is an important but still open question. Based on a model neuron with a cylindrical dendrite and lumped soma, we derive a formula that substantiates a proportionality between the local field potential and the total somatic transmembrane current that emerges from the difference between the somatic and dendritic membrane potentials. The formula is tested by intra- and extracellular recordings of evoked synaptic responses in hippocampal slices. Additionally, the contribution of different membrane currents to the field potential is demonstrated in a two-population mean-field model. Our formalism, which allows for a simple estimation of unknown dendritic currents directly from somatic measurements, provides an interpretation of the local field potential in terms of intracellularly measurable synaptic signals. It is also applicable to the study of cortical activity using two-compartment neuronal population models. PMID:26764724

  4. Compartment-Specific Phosphorylation of Squid Neurofilaments.

    PubMed

    Grant, Philip; Pant, Harish C

    2016-01-01

    Studies of the giant axon and synapse of third-order neurons in the squid stellate ganglion have provided a vast literature on neuronal physiology and axon transport. Large neuronal size also lends itself to comparative biochemical studies of cell body versus axon. These have focused on the regulation of synthesis, assembly, posttranslational modification and function of neuronal cytoskeletal proteins (microtubules (MTs) and neurofilaments (NFs)), the predominant proteins in axoplasm. These contribute to axonal organization, stability, transport, and impulse transmission responsible for rapid contractions of mantle muscles underlying jet propulsion. Studies of vertebrate NFs have established an extensive literature on NF structure, organization, and function; studies of squid NFs, however, have made it possible to compare compartment-specific regulation of NF synthesis, assembly, and function in soma versus axoplasm. Since NFs contain over 100 eligible sites for phosphorylation by protein kinases, the compartment-specific patterns of phosphorylation have been a primary focus of biochemical studies. We have learned that NF phosphorylation is tightly compartmentalized; extensive phosphorylation occurs only in the axonal compartment in squid and in vertebrate neurons. This extensive phosphorylation plays a key role in organizing NFs, in association with microtubules (MTs), into a stable, dynamic functional lattice that supports axon growth, diameter, impulse transmission, and synaptic activity. To understand how cytoskeletal phosphorylation is topographically regulated, the kinases and phosphatases, bound to NFs isolated from cell bodies and axoplasm, have also been studied.

  5. Dual-Compartment Inflatable Suitlock

    NASA Technical Reports Server (NTRS)

    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

  6. Dual-Compartment Inflatable Suitlock

    NASA Technical Reports Server (NTRS)

    Howe, Scott; Kennedy, Kriss J.; Guirgis, Peggy L.

    2012-01-01

    A paper discusses a dual-compartment inflatable suitlock (DCIS) for Extra - vehicular Activity (EVA) that will allow for dust control, suit maintenance, and efficient EVA egress/ingress. The expandable (inflatable technologies) aspect of the design will allow the unit to stow in a compact package for transport. The DCIS consists of three hard, in line 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 suited crewmember can quickly don a suit, and egress the suitlock without waiting for the compartment to depressurize. The outer compartment can be pressurized infrequently, when a long dwell time is expected prior to the next EVA, or during off-nominal suit maintenance tasks, allowing shirtsleeve inspections and maintenance of the space suits. The outer bulkhead has a pressure-assisted hatch door that stays open and stowed routinely, but can be closed for suit maintenance and pressurization as needed.

  7. Compartment syndrome following intraosseous infusion.

    PubMed

    Moen, Todd C; Sarwark, John F

    2008-08-01

    Intraosseous infusion is a valuable technique in the resuscitation of critically ill pediatric patients in whom vascular access has proved otherwise impossible. Although it is well established as a safe and reliable means of emergent access, intraosseous infusion is not without danger, nor complication. One of the rare yet most grave complications of intraosseous access is compartment syndrome. We report a case of compartment syndrome as a result of intraosseous infusion that serves to remind of the potential pitfalls of this technique. An otherwise healthy 6-year-old girl presented to our institution's pediatric intensive care unit following emergent resuscitation for a prolonged cardiac arrest. Approximately 1 hour following an uneventful soccer practice, without any antecedent cardiopulmonary symptoms or complaints, the patient collapsed and was unresponsive, not breathing, and pulseless. In the course of resuscitation, right and left tibial intraosseous lines were started. After 30 minutes of resuscitation, with multiple rounds of lidocaine and epinephrine infused through the intraosseous lines, a sustained perfusing rhythm was established. Acute compartment syndrome was diagnosed, and through anterolateral and posteromedial incisions, all 4 fascial compartments were released. While the condition of the patient's extremity improved, the overall clinical condition of the patient did not. This case highlights the fundamental principles regarding the use of intraosseous infusion and the diagnosis and management of compartment syndrome in critically ill patients. PMID:19292404

  8. 14 CFR 25.853 - Compartment interiors.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Compartment interiors. For each compartment occupied by the crew or passengers, the following apply: (a... and the cavity walls that are exposed when a full complement of such carts or containers is not... compartments, galleys, lavatories, crew rest quarters, cabinets and stowage compartments, need not meet...

  9. Metabolic coupling in urothelial bladder cancer compartments and its correlation to tumor aggressiveness.

    PubMed

    Afonso, Julieta; Santos, Lúcio L; Morais, António; Amaro, Teresina; Longatto-Filho, Adhemar; Baltazar, Fátima

    2016-01-01

    Monocarboxylate transporters (MCTs) are vital for intracellular pH homeostasis by extruding lactate from highly glycolytic cells. These molecules are key players of the metabolic reprogramming of cancer cells, and evidence indicates a potential contribution in urothelial bladder cancer (UBC) aggressiveness and chemoresistance. However, the specific role of MCTs in the metabolic compartmentalization within bladder tumors, namely their preponderance on the tumor stroma, remains to be elucidated. Thus, we evaluated the immunoexpression of MCTs in the different compartments of UBC tissue samples (n = 111), assessing the correlations among them and with the clinical and prognostic parameters. A significant decrease in positivity for MCT1 and MCT4 occurred from normoxic toward hypoxic regions. Significant associations were found between the expression of MCT4 in hypoxic tumor cells and in the tumor stroma. MCT1 staining in normoxic tumor areas, and MCT4 staining in hypoxic regions, in the tumor stroma and in the blood vessels were significantly associated with UBC aggressiveness. MCT4 concomitant positivity in hypoxic tumor cells and in the tumor stroma, as well as positivity in each of these regions concomitant with MCT1 positivity in normoxic tumor cells, was significantly associated with an unfavourable clinicopathological profile, and predicted lower overall survival rates among patients receiving platinum-based chemotherapy. Our results point to the existence of a multi-compartment metabolic model in UBC, providing evidence of a metabolic coupling between catabolic stromal and cancer cells' compartments, and the anabolic cancer cells. It is urgent to further explore the involvement of this metabolic coupling in UBC progression and chemoresistance. PMID:26636903

  10. Corynebacterium diphtheriae putative tellurite-resistance protein (CDCE8392_0813) contributes to the intracellular survival in human epithelial cells and lethality of Caenorhabditis elegans

    PubMed Central

    dos Santos, Louisy Sanches; Antunes, Camila Azevedo; dos Santos, Cintia Silva; Pereira, José Augusto Adler; Sabbadini, Priscila Soares; de Luna, Maria das Graças; Azevedo, Vasco; Hirata, Raphael; Burkovski, Andreas; Asad, Lídia Maria Buarque de Oliveira; Mattos-Guaraldi, Ana Luíza

    2015-01-01

    Corynebacterium diphtheriae, the aetiologic agent of diphtheria, also represents a global medical challenge because of the existence of invasive strains as causative agents of systemic infections. Although tellurite (TeO32-) is toxic to most microorganisms, TeO32--resistant bacteria, including C. diphtheriae, exist in nature. The presence of TeO32--resistance (TeR) determinants in pathogenic bacteria might provide selective advantages in the natural environment. In the present study, we investigated the role of the putative TeR determinant (CDCE8392_813gene) in the virulence attributes of diphtheria bacilli. The disruption of CDCE8392_0813 gene expression in the LDCIC-L1 mutant increased susceptibility to TeO32- and reactive oxygen species (hydrogen peroxide), but not to other antimicrobial agents. The LDCIC-L1 mutant also showed a decrease in both the lethality of Caenorhabditis elegans and the survival inside of human epithelial cells compared to wild-type strain. Conversely, the haemagglutinating activity and adherence to and formation of biofilms on different abiotic surfaces were not regulated through the CDCE8392_0813 gene. In conclusion, the CDCE8392_813 gene contributes to the TeR and pathogenic potential of C. diphtheriae. PMID:26107188

  11. Exploring Water-Tight Compartments.

    ERIC Educational Resources Information Center

    Fishman, Steve

    John Dewey employed the phrase "water-tight compartments" to mark deficiencies of integration within an individual's personality. For Dewey, the self is complex, but a strong personality integrates its various habits so that they reinforce rather than conflict with one another. Dewey's focus on this problem of personality has relevance for…

  12. Subcellular storage compartments of bacteriopheophorbide sensitizers

    NASA Astrophysics Data System (ADS)

    Moser, Joerg G.; Dembeck, U.; Hubert, M.; Spengler, Bernhard; Bayer, Rainer; Wagner, Birgit

    1994-03-01

    Fluorescence colocalization with the Golgi specific stain, NBD-ceramide, and the mitochondrial localizing stain, Rhodamine 123, confirmed the earlier assumption that the Golgi apparatus is one of the prominent storage compartments for bacteriopheophorbide esters in OAT 75 SCLC cells and several amelanotic melanoma cell lines (A375, Melur SP18, SkAMel 25). Furthermore, a diffuse staining of mitochondria, of non-structured cytoplasm, and an additional storage in melanine vesicles of the amelanotic melanoma cells suggests further storage compartments with quantitatively different contributions to the phototoxicity of bacteriochlorophyll-derived photosensitizers. Independent observations of early phototoxic effects on microfilamentous networks, enzymatic activities (succinate dehydrogenase, lactate dehydrogenase), and redistribution phenomena following primary uptake of the sensitizers let us assume that only a part of the 108 molecules taken up by a cell contribute directly to phototoxicity. Thus it may be asked if a proper subcellular positioning of only a few sensitizer molecules may have similar phototoxic effects as the huge amounts stored at apparently ineffective sites.

  13. Computer model of unstirred layer and intracellular pH changes. Determinants of unstirred layer pH.

    PubMed

    Marrannes, Roger

    2013-06-01

    Transmembrane acid-base fluxes affect the intracellular pH and unstirred layer pH around a superfused biological preparation. In this paper the factors influencing the unstirred layer pH and its gradient are studied. An analytical expression of the unstirred layer pH gradient in steady state is derived as a function of simultaneous transmembrane fluxes of (weak) acids and bases with the dehydration reaction of carbonic acid in equilibrium. Also a multicompartment computer model is described consisting of the extracellular bulk compartment, different unstirred layer compartments and the intracellular compartment. With this model also transient changes and the influence of carbonic anhydrase (CA) can be studied. The analytical expression and simulations with the multicompartment model demonstrate that in steady state the unstirred layer pH and its gradient are influenced by the size and type of transmembrane flux of acids and bases, their dissociation constant and diffusion coefficient, the concentration, diffusion coefficient and type of mobile buffers and the activity and location of CA. Similar principles contribute to the amplitude of the unstirred layer pH transients. According to these models an immobile buffer does not influence the steady-state pH, but reduces the amplitude of pH transients especially when these are fast. The unstirred layer pH provides useful information about transmembrane acid-base fluxes. This paper gives more insight how the unstirred layer pH and its transients can be interpreted. Methodological issues are discussed. PMID:23860924

  14. Computer model of unstirred layer and intracellular pH changes. Determinants of unstirred layer pH.

    PubMed

    Marrannes, Roger

    2013-06-01

    Transmembrane acid-base fluxes affect the intracellular pH and unstirred layer pH around a superfused biological preparation. In this paper the factors influencing the unstirred layer pH and its gradient are studied. An analytical expression of the unstirred layer pH gradient in steady state is derived as a function of simultaneous transmembrane fluxes of (weak) acids and bases with the dehydration reaction of carbonic acid in equilibrium. Also a multicompartment computer model is described consisting of the extracellular bulk compartment, different unstirred layer compartments and the intracellular compartment. With this model also transient changes and the influence of carbonic anhydrase (CA) can be studied. The analytical expression and simulations with the multicompartment model demonstrate that in steady state the unstirred layer pH and its gradient are influenced by the size and type of transmembrane flux of acids and bases, their dissociation constant and diffusion coefficient, the concentration, diffusion coefficient and type of mobile buffers and the activity and location of CA. Similar principles contribute to the amplitude of the unstirred layer pH transients. According to these models an immobile buffer does not influence the steady-state pH, but reduces the amplitude of pH transients especially when these are fast. The unstirred layer pH provides useful information about transmembrane acid-base fluxes. This paper gives more insight how the unstirred layer pH and its transients can be interpreted. Methodological issues are discussed.

  15. Bordetella pertussis entry into respiratory epithelial cells and intracellular survival.

    PubMed

    Lamberti, Yanina; Gorgojo, Juan; Massillo, Cintia; Rodriguez, Maria E

    2013-12-01

    Bordetella pertussis is the causative agent of pertussis, aka whooping cough. Although generally considered an extracellular pathogen, this bacterium has been found inside respiratory epithelial cells, which might represent a survival strategy inside the host. Relatively little is known, however, about the mechanism of internalization and the fate of B. pertussis inside the epithelia. We show here that B. pertussis is able to enter those cells by a mechanism dependent on microtubule assembly, lipid raft integrity, and the activation of a tyrosine-kinase-mediated signaling. Once inside the cell, a significant proportion of the intracellular bacteria evade phagolysosomal fusion and remain viable in nonacidic lysosome-associated membrane-protein-1-negative compartments. In addition, intracellular B. pertussis was found able to repopulate the extracellular environment after complete elimination of the extracellular bacteria with polymyxin B. Taken together, these data suggest that B. pertussis is able to survive within respiratory epithelial cells and by this means potentially contribute to host immune system evasion.

  16. Intracellular parcel service: current issues in intracellular membrane trafficking.

    PubMed

    Herrmann, Johannes M; Spang, Anne

    2015-01-01

    Eukaryotic cells contain a multitude of membrane structures that are connected through a highly dynamic and complex exchange of their constituents. The vibrant instability of these structures challenges the classical view of defined, static compartments that are connected by different types of vesicles. Despite this astonishing complexity, proteins and lipids are accurately transported into the different intracellular membrane systems. Over the past few decades many factors have been identified that either mediate or regulate intracellular membrane trafficking. Like in a modern parcel sorting system of a logistics center, the cargo typically passes through several sequential sorting stations until it finally reaches the location that is specified by its individual address label. While each membrane system employs specific sets of factors, the transport processes typically operate on common principles. With the advent of genome- and proteome-wide screens, the availability of mutant collections, exciting new developments in microscope technology and sophisticated methods to study their dynamics, the future promises a broad and comprehensive picture of the processes by which eukaryotic cells sort their proteins.

  17. Toward Intracellular Targeted Delivery of Cancer Therapeutics

    PubMed Central

    Pandya, Hetal; Debinski, Waldemar

    2013-01-01

    A number of anti-cancer drugs have their targets localized to particular intracellular compartments. These drugs reach the targets mainly through diffusion, dependent on biophysical and biochemical forces that allow cell penetration. This means that both cancer cells and normal cells will be subjected to such diffusion; hence many of these drugs, like chemotherapeutics, are potentially toxic and the concentration achieved at the site of their action is often suboptimal. The same relates to radiation that indiscriminately affects normal and diseased cells. However, nature-designed systems enable compounds present in the extracellular environment to end up inside the cell and even travel to more specific intracellular compartments. For example, viruses and bacterial toxins can more or less specifically recognize eukaryotic cells, enter these cells, and direct some protein portions to designated intracellular areas. These phenomena have led to creative thinking, such as employing viruses or bacterial toxins for cargo delivery to cells and, more specifically, to cancer cells. Proteins can be genetically engineered in order to not only mimic what viruses and bacterial toxins can do, but also to add new functions, extending or changing the intracellular routes. It is possible to make conjugates or, more preferably, single-chain proteins that recognize cancer cells and deliver cargo inside the cells, even to the desired subcellular compartment. These findings offer new opportunities to deliver drugs/labels only to cancer cells and only to their site of action within the cells. The development of such dual-specificity vectors for targeting cancer cells is an attractive and potentially safer and more efficacious way of delivering drugs. We provide examples of this approach for delivering brain cancer therapeutics, using a specific biomarker on glioblastoma tumor cells. PMID:22671766

  18. The Orbital Workshop Shower Compartment

    NASA Technical Reports Server (NTRS)

    1972-01-01

    This photograph shows technicians performing a checkout of the Metabolic Analyzer (center background) and the Ergometer (foreground) in the Orbital Workshop (OWS). The shower compartment is at right. The Ergometer (Skylab Experiment M171) evaluated man's metabolic effectiveness and cost of work in space environment. Located in the experiment and work area of the OWS, the shower compartment was a cylindrical cloth enclosure that was folded flat when not in use. The bottom ring of the shower was fastened to the floor and contained foot restraints. The upper ring contained the shower head and hose. To use the shower, the astronaut filled a pressurized portable bottle with heated water and attached the bottle to the ceiling. A flexible hose cornected the water bottle to a handheld shower head. The astronaut pulled the cylindrical shower wall up into position and bathed, using liquid soap. Both soap and water were carefully rationed, having been premeasured for economical use.

  19. The Orbital Workshop Shower Compartment

    NASA Technical Reports Server (NTRS)

    1972-01-01

    In this photograph, the Orbital Workshop shower compartment was unfolded by technicians for inspection. The shower compartment was a cylindrical cloth enclosure that was folded flat when not in use. The bottom ring of the shower was fastened to the floor and contained foot restraints. The upper ring contained the shower head and hose. To use the shower, the astronaut filled a pressurized portable bottle with heated water and attached the bottle to the ceiling. A flexible hose cornected the water bottle to a handheld shower head. The astronaut pulled the cylindrical shower wall up into position and bathed, using liquid soap. Both soap and water were carefully rationed, having been premeasured for economical use.

  20. 36 CFR 1192.127 - Sleeping compartments.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Intercity Rail Cars and Systems § 1192.127 Sleeping compartments. (a) Sleeping compartments required to be... controls, call buttons, electrical outlets, etc.) shall be mounted no more than 48 inches, and no less...

  1. 36 CFR 1192.127 - Sleeping compartments.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Intercity Rail Cars and Systems § 1192.127 Sleeping compartments. (a) Sleeping compartments required to be... controls, call buttons, electrical outlets, etc.) shall be mounted no more than 48 inches, and no less...

  2. 36 CFR 1192.127 - Sleeping compartments.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Intercity Rail Cars and Systems § 1192.127 Sleeping compartments. (a) Sleeping compartments required to be... controls, call buttons, electrical outlets, etc.) shall be mounted no more than 48 inches, and no less...

  3. 36 CFR 1192.127 - Sleeping compartments.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Intercity Rail Cars and Systems § 1192.127 Sleeping compartments. (a) Sleeping compartments required to be... controls, call buttons, electrical outlets, etc.) shall be mounted no more than 48 inches, and no less...

  4. Method and apparatus to assess compartment syndrome

    NASA Technical Reports Server (NTRS)

    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.

  5. Orbiter Crew Compartment Integration-Stowage

    NASA Technical Reports Server (NTRS)

    Morgan, L. Gary

    2007-01-01

    This viewgraph presentation describes the Orbiter Crew Compartment Integration (CCI) stowage. The evolution of orbiter crew compartment stowage volume is also described, along with photographs presented of the on-orbit volume stowage capacity.

  6. 36 CFR 1192.127 - Sleeping compartments.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true 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...

  7. 49 CFR 38.127 - Sleeping compartments.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Sleeping compartments. 38.127 Section 38.127... SPECIFICATIONS FOR TRANSPORTATION VEHICLES Intercity Rail Cars and Systems § 38.127 Sleeping compartments. (a) Sleeping compartments required to be accessible shall be designed so as to allow a person using...

  8. 49 CFR 38.127 - Sleeping compartments.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 1 2014-10-01 2014-10-01 false Sleeping compartments. 38.127 Section 38.127... SPECIFICATIONS FOR TRANSPORTATION VEHICLES Intercity Rail Cars and Systems § 38.127 Sleeping compartments. (a) Sleeping compartments required to be accessible shall be designed so as to allow a person using...

  9. 49 CFR 38.127 - Sleeping compartments.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 false Sleeping compartments. 38.127 Section 38.127... SPECIFICATIONS FOR TRANSPORTATION VEHICLES Intercity Rail Cars and Systems § 38.127 Sleeping compartments. (a) Sleeping compartments required to be accessible shall be designed so as to allow a person using...

  10. 14 CFR 27.771 - Pilot compartment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Pilot compartment. 27.771 Section 27.771... Pilot compartment. For each pilot compartment— (a) The compartment and its equipment must allow each pilot to perform his duties without unreasonable concentration or fatigue; (b) If there is provision...

  11. 14 CFR 29.771 - Pilot compartment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Pilot compartment. 29.771 Section 29.771... Pilot compartment. For each pilot compartment— (a) The compartment and its equipment must allow each pilot to perform his duties without unreasonable concentration or fatigue; (b) If there is provision...

  12. 14 CFR 27.771 - Pilot compartment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Pilot compartment. 27.771 Section 27.771... Pilot compartment. For each pilot compartment— (a) The compartment and its equipment must allow each pilot to perform his duties without unreasonable concentration or fatigue; (b) If there is provision...

  13. 14 CFR 29.771 - Pilot compartment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Pilot compartment. 29.771 Section 29.771... Pilot compartment. For each pilot compartment— (a) The compartment and its equipment must allow each pilot to perform his duties without unreasonable concentration or fatigue; (b) If there is provision...

  14. 14 CFR 29.853 - Compartment interiors.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Compartment interiors. For each compartment to be used by the crew or passengers— (a) The materials (including finishes or decorative surfaces applied to the materials) must meet the following test criteria as... walls, structural flooring, and materials used in the construction of stowage compartments (other...

  15. 14 CFR 29.853 - Compartment interiors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Compartment interiors. For each compartment to be used by the crew or passengers— (a) The materials (including finishes or decorative surfaces applied to the materials) must meet the following test criteria as... walls, structural flooring, and materials used in the construction of stowage compartments (other...

  16. Heat shock protein 70 (Hsp70) interacts with the Notch1 intracellular domain and contributes to the activity of Notch signaling in myelin-reactive CD4 T cells.

    PubMed

    Juryńczyk, Maciej; Lewkowicz, Przemysław; Domowicz, Małgorzata; Mycko, Marcin P; Selmaj, Krzysztof W

    2015-10-15

    Notch receptors (Notch1-4) are involved in the differentiation of CD4 T cells and the development of autoimmunity. Mechanisms regulating Notch signaling in CD4 T cells are not fully elucidated. In this study we investigated potential crosstalk between Notch pathway molecules and heat shock protein 70 (Hsp70), the major intracellular chaperone involved in the protein transport during immune responses and other stress conditions. Using Hsp70(-/-) mice we found that Hsp70 is critical for up-regulation of NICD1 and induction of Notch target genes in Jagged1- and Delta-like1-stimulated CD4 T cells. Co-immunoprecipitation analysis of wild-type CD4 T cells stimulated with either Jagged1 or Delta-like1 showed a direct interaction between NICD1 and Hsp70. Both molecules co-localized within the nucleus of CD4 T cells stimulated with Notch ligands. Molecular interaction and nuclear colocalization of NICD1 and Hsp70 were also detected in CD4 T cells reactive against myelin oligodendrocyte glycoprotein (MOG)35-55, which showed Hsp70-dependent up-regulation of both NICD1 and Notch target genes. In conclusion, we demonstrate for the first time that Hsp70 interacts with NICD1 and contributes to the activity of Notch signaling in CD4 T cells. Interaction between Hsp70 and NICD1 may represent a novel mechanism regulating Notch signaling in activated CD4 T cells.

  17. Brush border myosin-I truncated in the motor domain impairs the distribution and the function of endocytic compartments in an hepatoma cell line.

    PubMed Central

    Durrbach, A; Collins, K; Matsudaira, P; Louvard, D; Coudrier, E

    1996-01-01

    Myosins I, a ubiquitous monomeric class of myosins that exhibits actin-based motor properties, are associated with plasma and/or vesicular membranes and have been suggested as players for trafficking events between cell surface and intracellular membranous structures. To investigate the function of myosins 1, we have transfected a mouse hepatoma cell line (BWTG3) with cDNAs encoding the chicken brush border myosin-I (BBMI) and two variants truncated in the motor domain. One variant is deleted of the first 446 amino acids and thereby lacks the ATP binding site, whereas the other is deleted of the entire motor domain and lacks the ATP and actin binding sites. We have observed (i) that significant amounts of the truncated variants are recovered with membrane fractions after cell fractionation, (ii) that they codistribute with a compartment containing alpha2-macroglobulin internalized for 30 min as determined by fluorescent microscopy, (iii) that the production of BBMI-truncated variants impairs the distribution of the acidic compartment and ligands internalized for 30 min, and (iv) that the production of the truncated variant containing the actin binding site decreases the rate of alpha2-macroglobulin degradation whereas the production of the variant lacking the ATP binding site and the actin binding site increases the rate of a2-macroglobulin degradation. These observations indicate that the two truncated variants have a dominant negative effect on the distribution and the function of the endocytic compartments. We propose that an unidentified myosin-I might contribute to the distribution of endocytic compartments in a juxtanuclear position and/or to the regulation of the delivery of ligands to the degradative compartment in BWTG3 cells. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:8692943

  18. Exertional compartment syndromes of the lower extremity.

    PubMed

    Schepsis, A A; Lynch, G

    1996-03-01

    Compartment syndromes may be acute or chronic secondary to exertion or exercise. The chronic or exertional type most commonly involves the lower extremity, particularly the anterior compartment of the lower leg, and is the subject of this review. Rarely, an exertional compartment syndrome may become acute. The diagnosis is based on history, physical examination, and compartment pressure measurements. The differential diagnosis of exertional leg pain includes stress fractures, stress reaction, periostitis, claudication, popliteal artery entrapment, and peripheral nerve entrapment. Unusual causes, such as a ganglion of the proximal tibiofibular joint causing an anterior compartment syndrome, have recently been reported.

  19. Live cell imaging of intracellular Salmonella enterica.

    PubMed

    Kehl, Alexander; Hensel, Michael

    2015-01-01

    During the intracellular phase of the pathogenic lifestyle, Salmonella enterica massively alters the endosomal system of its host cells. Two hallmarks are the remodeling of phagosomes into the Salmonella-containing vacuole (SCV) as a replicative niche, and the formation of tubular structures, such as Salmonella-induced filaments (SIFs). To study the dynamics and the fate of these Salmonella-specific compartments, live cell imaging (LCI) is a method of choice. In this chapter, we compare currently used microscopy techniques and focus on considerations and requirements specific for LCI. Detailed protocols for LCI of Salmonella infection with either confocal laser scanning microscopy (CLSM) or spinning disk confocal microscopy (SDCM) are provided.

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

    PubMed

    Canton, Johnathan; Kima, Peter E

    2012-11-01

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

  1. RAB24 facilitates clearance of autophagic compartments during basal conditions

    PubMed Central

    Ylä-Anttila, Päivi; Mikkonen, Elisa; Happonen, Kaisa E; Holland, Petter; Ueno, Takashi; Simonsen, Anne; Eskelinen, Eeva-Liisa

    2015-01-01

    RAB24 belongs to a family of small GTPases and has been implicated to function in autophagy. Here we confirm the intracellular localization of RAB24 to autophagic vacuoles with immuno electron microscopy and cell fractionation, and show that prenylation and guanine nucleotide binding are necessary for the targeting of RAB24 to autophagic compartments. Further, we show that RAB24 plays a role in the maturation and/or clearance of autophagic compartments under nutrient-rich conditions, but not during short amino acid starvation. Quantitative electron microscopy shows an increase in the numbers of late autophagic compartments in cells silenced for RAB24, and mRFP-GFP-LC3 probe and autophagy flux experiments indicate that this is due to a hindrance in their clearance. Formation of autophagosomes is shown to be unaffected by RAB24-silencing with siRNA. A defect in aggregate clearance in the absence of RAB24 is also shown in cells forming polyglutamine aggregates. This study places RAB24 function in the termination of the autophagic process under nutrient-rich conditions. PMID:26325487

  2. Intracellular Bacteria in Protozoa

    NASA Astrophysics Data System (ADS)

    Görtz, Hans-Dieter; Brigge, Theo

    Intracellular bacteria in humans are typically detrimental, and such infections are regarded by the patients as accidental and abnormal. In protozoa it seems obvious that many bacteria have coevolved with their hosts and are well adapted to the intracellular way of life. Manifold interactions between hosts and intracellular bacteria are found, and examples of antibacterial resistance of unknown mechanisms are observed. The wide diversity of intracellular bacteria in protozoa has become particularly obvious since they have begun to be classified by molecular techniques. Some of the bacteria are closely related to pathogens; others are responsible for the production of toxins.

  3. Chronic compartment syndrome: diagnosis, management, and outcomes.

    PubMed

    Detmer, D E; Sharpe, K; Sufit, R L; Girdley, F M

    1985-01-01

    A consecutive operative series of 100 patients with chronic compartment syndrome involving 233 compartments is reported. Seven of every eight were athletes, and runners predominated. Exercise-induced symptoms of consistently recurring tightness, aching (in some, sharp pains) in anatomically defined compartments were pathognomonic. Mean months of symptoms prior to operation was 22; median age was 26 years. Bilaterality occurred in 82. The distribution of compartments was: anterior, 39%; lateral, 12%; and posterior, 48%. Incidental compartment pressures were elevated (mean = 23 mmHg). Fasciotomy using local anesthesia was performed on 70 outpatients. At a median of 4.5 months, over 90% were cured or significantly improved in symptoms and/or function. Median time to walking unassisted was 2 days, and to resumption of conditioned running 21 days. Fasciotomy can be a safe, effective, and economical treatment for chronic compartment syndrome.

  4. Endosomal escape: a bottleneck in intracellular delivery.

    PubMed

    Shete, Harshad K; Prabhu, Rashmi H; Patravale, Vandana B

    2014-01-01

    With advances in therapeutic science, apart from drugs, newer bioactive moieties like oligonucleotides, proteins, peptides, enzymes and antibodies are constantly being introduced for the betterment of therapeutic efficacy. These moieties have intracellular components of the cells like cytoplasm and nucleus as one of their pharmacological sites for exhibiting therapeutic activity. Despite their promising efficacy, their intracellular bioavailability has been critically hampered leading to failure in the treatment of numerous diseases and disorders. The endosomal uptake pathway is known to be a rate-limiting barrier for such systems. Bioactive molecules get trapped in the endosomal vesicles and degraded in the lysosomal compartment, necessitating the need for effective strategies that facilitate the endosomal escape and enhance the cytosolic bioavailability of bioactives. Microbes like viruses and bacteria have developed their innate mechanistic tactics to translocate their genome and toxins by efficiently penetrating the host cell membrane. Understanding this mechanism and exploring it further for intracellular delivery has opened new avenues to surmount the endosomal barrier. These strategies include membrane fusion, pore formation and proton sponge effects. On the other hand, progress in designing a novel smart polymeric carrier system that triggers endosomal escape by undergoing modulations in the intracellular milieu has further led to an improvement in intracellular delivery. These comprise pH, enzyme and temperature-induced modulators, synthetic cationic lipids and photo-induced physical disruption. Each of the aforementioned strategies has its own unique mechanism to escape the endosome. This review recapitulates the numerous strategies designed to surmount the bottleneck of endosomal escape and thereby achieve successful intracellular uptake of bioactives. PMID:24730275

  5. Acute lower-leg compartment syndrome.

    PubMed

    Mauser, Nathan; Gissel, Hannah; Henderson, Corey; Hao, Jiandong; Hak, David; Mauffrey, Cyril

    2013-08-01

    Acute compartment syndrome remains a challenging problem for orthopedic surgeons because its diagnosis is not always straightforward and it has a high risk of associated limb morbidity if left undiagnosed or untreated. Failure to diagnose and treat acute compartment syndrome is one of the most common causes of successful medical liability claims. The authors review the current literature concerning the diagnosis of acute compartment syndrome and discuss new non-invasive technologies that may allow for earlier and more accurate diagnosis of impending acute compartment syndrome.

  6. Compartment syndrome: A quantitative study of high-energy phosphorus compounds using sup 31 P-magnetic resonance spectroscopy

    SciTech Connect

    Heppenstall, R.B.; Sapega, A.A.; Izant, T.; Fallon, R.; Shenton, D.; Park, Y.S.; Chance, B. )

    1989-08-01

    The purpose of this study was to quantitate the intracellular high-energy phosphate compounds during 6 hours of tissue ischemia in the anterior tibial compartment of beagles subjected to an induced traumatized compartment syndrome. The goal of this work was to provide clinicians with objective criteria to augment clinical judgment regarding surgical intervention in the impending compartment syndrome. A beagle model was utilized in which the Delta pressure (difference between the mean arterial pressure and compartment pressure) could be controlled. The model, in conjunction with {sup 31}P-magnetic resonance spectroscopy (MRS), allowed a measure of high-energy phosphate compounds and pH in the compartment at various Delta pressures. The extent of ischemic metabolic insult in the compartment was then quantitated. Our data suggest the following: (1) lower Delta pressures result in a proportionally greater drop in the intracellular phosphocreatine ratio and pH; (2) at lower Delta pressures, there is proportionally greater decline in the percentage recovery post-fasciotomy; (3) blood pressure is extremely important and periods of hypotension may result in increased muscle damage at lower compartment pressures.

  7. Internalized compartments encapsulated nanogels for targeted drug delivery

    NASA Astrophysics Data System (ADS)

    Yu, Jicheng; Zhang, Yuqi; Sun, Wujin; Wang, Chao; Ranson, Davis; Ye, Yanqi; Weng, Yuyan; Gu, Zhen

    2016-04-01

    Drug delivery systems inspired by natural particulates hold great promise for targeted cancer therapy. An endosome formed by internalization of plasma membrane has a massive amount of membrane proteins and receptors on the surface, which is able to specifically target the homotypic cells. Herein, we describe a simple method to fabricate an internalized compartments encapsulated nanogel with endosome membrane components (EM-NG) from source cancer cells. Following intracellular uptake of methacrylated hyaluronic acid (m-HA) adsorbed SiO2/Fe3O4 nanoparticles encapsulating a crosslinker and a photoinitiator, EM-NG was readily prepared through in situ crosslinking initiated under UV irradiation after internalization. The resulting nanogels loaded with doxorubicin (DOX) displayed enhanced internalization efficiency to the source cells through a specific homotypic affinity in vitro. However, when treated with the non-source cells, the EM-NGs exhibited insignificant difference in therapeutic efficiency compared to a bare HA nanogel with DOX. This study illustrates the potential of utilizing an internalized compartments encapsulated formulation for targeted cancer therapy, and offers guidelines for developing a natural particulate-inspired drug delivery system.Drug delivery systems inspired by natural particulates hold great promise for targeted cancer therapy. An endosome formed by internalization of plasma membrane has a massive amount of membrane proteins and receptors on the surface, which is able to specifically target the homotypic cells. Herein, we describe a simple method to fabricate an internalized compartments encapsulated nanogel with endosome membrane components (EM-NG) from source cancer cells. Following intracellular uptake of methacrylated hyaluronic acid (m-HA) adsorbed SiO2/Fe3O4 nanoparticles encapsulating a crosslinker and a photoinitiator, EM-NG was readily prepared through in situ crosslinking initiated under UV irradiation after internalization. The

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

    PubMed Central

    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. PMID:26538766

  9. 14 CFR 25.787 - Stowage compartments.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Stowage compartments. 25.787 Section 25.787 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... equipment (such as life rafts), and any other stowage compartment must be designed for its placarded...

  10. 14 CFR 25.787 - Stowage compartments.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Stowage compartments. 25.787 Section 25.787 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... equipment (such as life rafts), and any other stowage compartment must be designed for its placarded...

  11. 14 CFR 25.787 - Stowage compartments.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Stowage compartments. 25.787 Section 25.787 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Personnel and Cargo Accommodations § 25.787 Stowage compartments. (a)...

  12. Cell communication compartments in molluscan embryos.

    PubMed

    Serras, F; Kühtreiber, W M; Krul, M R; van den Biggelaar, J A

    1985-08-01

    Early embryos of Patella vulgata have been injected with Lucifer Yellow. No restriction of dye spread was found. We show that later in the development, the larval trochophore stage present evidence of compartments of cell communication. These dye compartments coincide with different presumptive regions. PMID:4028198

  13. Inositol 1,4,5-triphosphate-mediated shuttling between intracellular stores and the cytosol contributes to the sustained elevation in cytosolic calcium in FMLP-activated human neutrophils.

    PubMed

    Anderson, Ronald; Steel, Helen C; Tintinger, Gregory R

    2005-06-01

    The current study was designed to probe Ca2+ shuttling between intracellular stores and the cytosol as a potential mechanism contributing to the prolongation of elevated Ca2+ transients in N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP)-activated human neutrophils. Cytosolic Ca2+ concentrations and transmembrane fluxes of the cation were measured using spectrofluorimetric and radiometric procedures, respectively, while inositol 1,4,5-triphosphate (IP3) was measured using a radioreceptor assay. The Ca2+-chelating agent, ethylene glycol-bis (beta-aminoethyl ether) N,N,N'N'-tetraacetic acid (EGTA; 10mM), was used to exclude store-operated influx of Ca2+ into neutrophils, while the IP3 receptor antagonist, 2-aminoethoxydiphenyl borate (2-APB, 100 microM), added to the cells 10s after FMLP (0.01 and 1 microM), at which time the increases in IP3 and cytosolic Ca2+ were maximal, was used to eliminate both sustained release from stores and influx of Ca2+. Addition of FMLP at 0.01 or 1 microM resulted in equivalent peak increases in cytosolic Ca2+, while the increase in IP3 was greater and the rate of clearance of Ca2+ from the cytosol slower, in cells activated with 1 microM FMLP. Treatment of the cells with either EGTA or 2-APB following addition of 1 microM FMLP, completely (EGTA) or almost completely (2-APB) abolished the influx of Ca2+ and accelerated the rate of clearance of the cation from the cytosol. Post-peak cytosolic Ca2+ concentrations were lower, and the Ca2+ content of the stores higher, in cells treated with 2-APB. The involvement of IP3 was confirmed by similar findings in cells treated with U-73122 (1 microM), a selective inhibitor of phospholipase C. Taken together, these observations are compatible with IP3-mediated Ca2+ shuttling in neutrophils activated with FMLP.

  14. Compartmented mode workstation (CMW) comparisons

    SciTech Connect

    Tolliver, J.S.

    1995-12-31

    As the Compartmented Mode Workstation (CMW) market has matured, several vendors have released new versions of their CMW operating systems. These include a new version from SecureWare (CMW + Version 2.4), and Sun`s CMW 1.1 (also known as Trusted Solaris 1.1). EC is now shipping MLS+ 3.0 for DEC Alpha platforms. Relatively new entries in the market include Loral B1/CMW for IBM RS/6000 platforms and a SecureWare-based CMW for HP platforms (HP-UX 10.09). With all these choices it is time for a comparative analysis of the features offered by the various vendors. The authors have three of the above five CMW systems plus HP-UX BLS 9.09, which is a multilevel secure operating system (OS) targeted at the B1 level but not a CMW. Each is unique in sometimes obvious, sometimes subtle ways, a situation that requires knowing and keeping straight a variety of commands to do the same thing on each system. Some vendors offer extensive GUI tools for system administration; some require entering command-line commands for certain system administration tasks. They examine the differences in system installation, system administration, and system operating among the systems. They look at trusted networking among the various systems and differences in the network databases and label encodings files. They examine the user interface on the various systems from logging in to logging out.

  15. Autophagic clearance of bacterial pathogens: molecular recognition of intracellular microorganisms

    PubMed Central

    Mansilla Pareja, Maria Eugenia; Colombo, Maria I.

    2013-01-01

    Autophagy is involved in several physiological and pathological processes. One of the key roles of the autophagic pathway is to participate in the first line of defense against the invasion of pathogens, as part of the innate immune response. Targeting of intracellular bacteria by the autophagic machinery, either in the cytoplasm or within vacuolar compartments, helps to control bacterial proliferation in the host cell, controlling also the spreading of the infection. In this review we will describe the means used by diverse bacterial pathogens to survive intracellularly and how they are recognized by the autophagic molecular machinery, as well as the mechanisms used to avoid autophagic clearance. PMID:24137567

  16. Autophagic clearance of bacterial pathogens: molecular recognition of intracellular microorganisms.

    PubMed

    Pareja, Maria Eugenia Mansilla; Colombo, Maria I

    2013-01-01

    Autophagy is involved in several physiological and pathological processes. One of the key roles of the autophagic pathway is to participate in the first line of defense against the invasion of pathogens, as part of the innate immune response. Targeting of intracellular bacteria by the autophagic machinery, either in the cytoplasm or within vacuolar compartments, helps to control bacterial proliferation in the host cell, controlling also the spreading of the infection. In this review we will describe the means used by diverse bacterial pathogens to survive intracellularly and how they are recognized by the autophagic molecular machinery, as well as the mechanisms used to avoid autophagic clearance.

  17. Intracellular calcium channels in protozoa.

    PubMed

    Docampo, Roberto; Moreno, Silvia N J; Plattner, Helmut

    2014-09-15

    Ca(2+)-signaling pathways and intracellular Ca(2+) channels are present in protozoa. Ancient origin of inositol 1,4,5-trisphosphate receptors (IP3Rs) and other intracellular channels predates the divergence of animals and fungi as evidenced by their presence in the choanoflagellate Monosiga brevicollis, the closest known relative to metazoans. The first protozoan IP3R cloned, from the ciliate Paramecium, displays strong sequence similarity to the rat type 3 IP3R. This ciliate has a large number of IP3- and ryanodine(Ry)-like receptors in six subfamilies suggesting the evolutionary adaptation to local requirements for an expanding diversification of vesicle trafficking. IP3Rs have also been functionally characterized in trypanosomatids, where they are essential for growth, differentiation, and establishment of infection. The presence of the mitochondrial calcium uniporter (MCU) in a number of protozoa indicates that mitochondrial regulation of Ca(2+) signaling is also an early appearance in evolution, and contributed to the discovery of the molecular nature of this channel in mammalian cells. There is only sequence evidence for the occurrence of two-pore channels (TPCs), transient receptor potential Ca(2+) channels (TRPCs) and intracellular mechanosensitive Ca(2+)-channels in Paramecium and in parasitic protozoa.

  18. Intracellular Calcium Channels in Protozoa

    PubMed Central

    Docampo, Roberto; Moreno, Silvia N.J.; Plattner, Helmut

    2014-01-01

    Ca2+-signaling pathways and intracellular Ca2+ channels are present in protozoa. Ancient origin of inositol 1,4,5-trisphosphate receptors (IP3Rs) and other intracellular channels predates the divergence of animals and fungi as evidenced by their presence in the choanoflagellate Monosiga brevicollis, the closest known relative to metazoans. The first protozoan IP3R cloned, from the ciliate Paramecium, displays strong sequence similarity to the rat type 3 IP3R. This ciliate has a large number of IP3- and ryanodine(Ry)-like receptors in 6 subfamilies suggesting the evolutionary adaptation to local requirements for an expanding diversification of vesicle trafficking. IP3Rs have also been functionally characterized in trypanosomatids, where they are essential for growth, differentiation, and establishment of infection. The presence of the mitochondrial calcium uniporter (MCU) in a number of protozoa indicates that mitochondrial regulation of Ca2+ signaling is also an early appearance in evolution, and contributed to the discovery of the molecular nature of this channel in mammalian cells. There is only sequence evidence for the occurrence of two-pore channels (TPCs), transient receptor potential Ca2+ channels (TRPCs) and intracellular mechanosensitive Ca2+-channels in Paramecium and in parasitic protozoa. PMID:24291099

  19. Membrane contact sites between pathogen-containing compartments and host organelles.

    PubMed

    Dumoux, Maud; Hayward, Richard D

    2016-08-01

    Intracellular pathogens survive and replicate within specialised membrane-bound compartments that can be considered as pseudo-organelles. Using the obligate intracellular bacterium Chlamydia as an illustrative example, we consider the modes of lipid transport between pathogen-containing compartments and host organelles, including the formation of static membrane contact sites. We discuss how lipid scavenging can be mediated via the reprogramming of cellular transporters at these interfaces and describe recent data suggesting that pathogen effectors modulate the formation of specific membrane contacts. Further study of these emerging mechanisms is likely to yield new insights into the cell biology of lipid transport and organelle communication, which highlights potential new targets and strategies for future therapeutics. This article is part of a Special Issue entitled: The cellular lipid landscape edited by Tim P. Levine and Anant K. Menon. PMID:26825687

  20. Cellular Exit Strategies of Intracellular Bacteria.

    PubMed

    Hybiske, Kevin; Stephens, Richard

    2015-12-01

    The coevolution of intracellular bacteria with their eukaryotic hosts has presented these pathogens with numerous challenges for their evolutionary progress and survival. Chief among these is the ability to exit from host cells, an event that is fundamentally linked to pathogen dissemination and transmission. Recent years have witnessed a major expansion of research in this area, and this chapter summarizes our current understanding of the spectrum of exit strategies that are exploited by intracellular pathogens. Clear themes regarding the mechanisms of microbial exit have emerged and are most easily conceptualized as (i) lysis of the host cell, (ii) nonlytic exit of free bacteria, and (iii) release of microorganisms into membrane-encased compartments. The adaptation of particular exit strategies is closely linked with additional themes in microbial pathogenesis, including host cell death, manipulation of host signaling pathways, and coincident activation of proinflammatory responses. This chapter will explore the molecular determinants used by intracellular pathogens to promote host cell escape and the infectious advantages each exit pathway may confer, and it will provide an evolutionary framework for the adaptation of these mechanisms. PMID:27337274

  1. Compartment syndrome complicating tibial tubercle avulsion.

    PubMed

    Pape, J M; Goulet, J A; Hensinger, R N

    1993-10-01

    Avulsion of the tibial tubercle is an uncommon physeal injury. Complications from this fracture are infrequent. Adolescent boys developed compartment syndrome after tibial tubercle avulsion. Injury to the soft tissue surrounding the tibial tubercle avulsion may be more extensive than is usually appreciated. The anatomy of the proximal tibia and the tibial tubercle with nearby branches of the anterior tibial recurrent artery suggest a predisposing factor for the development of compartment syndrome. Compartment syndrome should be added to the list of possible complications of tibial tubercle avulsion fractures.

  2. Protein kinase C mu is located at the Golgi compartment

    PubMed Central

    1996-01-01

    Protein kinase C mu (PKC mu) displays unusual structural features like a pleckstrin homology domain and an amino-terminal hydrophobic region with a putative leader peptide and transmembrane sequence. As a discrete location often is a direct clue to the potential biological function of a kinase, antibodies directed against unique amino- and carboxy-terminal domains of PKC mu were used to localize the protein within intracellular compartments in immunofluorescence and subcellular fractionation studies. Confocal laser scanning microscopy showed colocalization of PKC mu with the resident Golgi marker protein beta 1,4 galactosyltransferase in PKC mu transfectants and in the human hepatocellular carcinoma cell line HepG2, expressing endogenous PKC mu. Long-term treatment of cells with brefeldin A, which disintegrates the Golgi apparatus, disrupted PKC mu-specific staining. Cosegregation of PKC mu with beta 1,4 galactosyltransferase, but not with the endosomal marker rab5, upon density gradient fractionation and Western blot analysis of HepG2 cell extracts, provides independent evidence for a Golgi localization of PKC mu. Moreover, cellular sulfate uptake and Golgi-specific glycosaminoglycan sulfation was enhanced in PKC mu transfectants. Together, these data suggest that PKC mu is a resident protein kinase of the core Golgi compartment and is involved in basal transport processes. PMID:8830770

  3. An Intracellular Nanotrap Redirects Proteins and Organelles in Live Bacteria

    PubMed Central

    Borg, Sarah; Popp, Felix; Hofmann, Julia; Leonhardt, Heinrich; Rothbauer, Ulrich

    2015-01-01

    ABSTRACT  Owing to their small size and enhanced stability, nanobodies derived from camelids have previously been used for the construction of intracellular “nanotraps,” which enable redirection and manipulation of green fluorescent protein (GFP)-tagged targets within living plant and animal cells. By taking advantage of intracellular compartmentalization in the magnetic bacterium Magnetospirillum gryphiswaldense, we demonstrate that proteins and even entire organelles can be retargeted also within prokaryotic cells by versatile nanotrap technology. Expression of multivalent GFP-binding nanobodies on magnetosomes ectopically recruited the chemotaxis protein CheW1-GFP from polar chemoreceptor clusters to the midcell, resulting in a gradual knockdown of aerotaxis. Conversely, entire magnetosome chains could be redirected from the midcell and tethered to one of the cell poles. Similar approaches could potentially be used for building synthetic cellular structures and targeted protein knockdowns in other bacteria. Importance   Intrabodies are commonly used in eukaryotic systems for intracellular analysis and manipulation of proteins within distinct subcellular compartments. In particular, so-called nanobodies have great potential for synthetic biology approaches because they can be expressed easily in heterologous hosts and actively interact with intracellular targets, for instance, by the construction of intracellular “nanotraps” in living animal and plant cells. Although prokaryotic cells also exhibit a considerable degree of intracellular organization, there are few tools available equivalent to the well-established methods used in eukaryotes. Here, we demonstrate the ectopic retargeting and depletion of polar membrane proteins and entire organelles to distinct compartments in a magnetotactic bacterium, resulting in a gradual knockdown of magneto-aerotaxis. This intracellular nanotrap approach has the potential to be applied in other bacteria for

  4. 14 CFR 25.787 - Stowage compartments.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... corresponding to the specified flight and ground load conditions, and to the emergency landing conditions of... to compartments located below, or forward, of all occupants in the airplane. If the airplane has...

  5. 14 CFR 25.787 - Stowage compartments.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... corresponding to the specified flight and ground load conditions, and to the emergency landing conditions of... to compartments located below, or forward, of all occupants in the airplane. If the airplane has...

  6. 14 CFR 29.853 - Compartment interiors.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... and nondecorative coated fabrics, leather, trays and galley furnishings, electrical conduit, thermal and acoustical insulation and insulation covering, air ducting, joint and edge covering, cargo compartment liners, insulation blankets, cargo covers, and transparencies, molded and thermoformed parts,...

  7. 14 CFR 29.853 - Compartment interiors.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... and nondecorative coated fabrics, leather, trays and galley furnishings, electrical conduit, thermal and acoustical insulation and insulation covering, air ducting, joint and edge covering, cargo compartment liners, insulation blankets, cargo covers, and transparencies, molded and thermoformed parts,...

  8. 14 CFR 29.853 - Compartment interiors.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... and nondecorative coated fabrics, leather, trays and galley furnishings, electrical conduit, thermal and acoustical insulation and insulation covering, air ducting, joint and edge covering, cargo compartment liners, insulation blankets, cargo covers, and transparencies, molded and thermoformed parts,...

  9. 49 CFR 38.127 - Sleeping compartments.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SPECIFICATIONS FOR TRANSPORTATION VEHICLES Intercity Rail Cars and Systems § 38.127 Sleeping compartments. (a...., heating and air conditioning controls, lighting controls, call buttons, electrical outlets, etc.) shall...

  10. 49 CFR 38.127 - Sleeping compartments.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... SPECIFICATIONS FOR TRANSPORTATION VEHICLES Intercity Rail Cars and Systems § 38.127 Sleeping compartments. (a...., heating and air conditioning controls, lighting controls, call buttons, electrical outlets, etc.) shall...

  11. Compartment syndrome after tibial plateau fracture☆

    PubMed Central

    Pitta, Guilherme Benjamin Brandão; dos Santos, Thays Fernanda Avelino; dos Santos, Fernanda Thaysa Avelino; da Costa Filho, Edelson Moreira

    2014-01-01

    Fractures of the tibial plateau are relatively rare, representing around 1.2% of all fractures. The tibia, due to its subcutaneous location and poor muscle coverage, is exposed and suffers large numbers of traumas, not only fractures, but also crush injuries and severe bruising, among others, which at any given moment, could lead compartment syndrome in the patient. The case is reported of a 58-year-old patient who, following a tibial plateau fracture, presented compartment syndrome of the leg and was submitted to decompressive fasciotomy of the four right compartments. After osteosynthesis with internal fixation of the tibial plateau using an L-plate, the patient again developed compartment syndrome. PMID:26229779

  12. Acute compartment syndrome of the upper extremity.

    PubMed

    Prasarn, Mark L; Ouellette, Elizabeth A

    2011-01-01

    Acute compartment syndrome occurs when pressure within a fibro-osseous space increases to a level that results in a decreased perfusion gradient across tissue capillary beds. Compartment syndromes of the hand, forearm, and upper arm can result in tissue necrosis, which can lead to devastating loss of function. The etiology of acute compartment syndrome in the upper extremity is diverse, and a high index of suspicion must be maintained. Pain out of proportion to injury is the most reliable early symptom of impending compartment syndrome. Diagnosis is particularly difficult in obtunded patients and in young children. Early recognition and expeditious surgical treatment are essential to obtain a good clinical outcome and prevent permanent disability.

  13. Chloride Channels of Intracellular Membranes

    PubMed Central

    Edwards, John C.; Kahl, Christina R.

    2010-01-01

    Proteins implicated as intracellular chloride channels include the intracellular ClC proteins, the bestrophins, the cystic fibrosis transmembrane conductance regulator, the CLICs, and the recently described Golgi pH regulator. This paper examines current hypotheses regarding roles of intracellular chloride channels and reviews the evidence supporting a role in intracellular chloride transport for each of these proteins. PMID:20100480

  14. Numerical analysis of air-flow and temperature field in a passenger car compartment

    NASA Astrophysics Data System (ADS)

    Kamar, Haslinda Mohamed; Kamsah, Nazri; Mohammad Nor, Ahmad Miski

    2012-06-01

    This paper presents a numerical study on the temperature field inside a passenger's compartment of a Proton Wira saloon car using computational fluid dynamics (CFD) method. The main goal is to investigate the effects of different glazing types applied onto the front and rear windscreens of the car on the distribution of air-temperature inside the passenger compartment in the steady-state conditions. The air-flow condition in the passenger's compartment is also investigated. Fluent CFD software was used to develop a three-dimensional symmetrical model of the passenger's compartment. Simplified representations of the driver and one rear passenger were incorporated into the CFD model of the passenger's compartment. Two types of glazing were considered namely clear insulated laminated tint (CIL) with a shading coefficient of 0.78 and green insulated laminate tint (GIL) with a shading coefficient of 0.5. Results of the CFD analysis were compared with those obtained when the windscreens are made up of clear glass having a shading coefficient of 0.86. Results of the CFD analysis show that for a given glazing material, the temperature of the air around the driver is slightly lower than the air around the rear passenger. Also, the use of GIL glazing material on both the front and rear windscreens significantly reduces the air temperature inside the passenger's compartment of the car. This contributes to a better thermal comfort condition to the occupants. Swirling air flow condition occurs in the passenger compartment. The air-flow intensity and velocity are higher along the side wall of the passenger's compartment compared to that along the middle section of the compartment. It was also found that the use of glazing materials on both the front and rear windscreen has no significant effects on the air-flow condition inside the passenger's compartment of the car.

  15. Aircraft Cargo Compartment Fire Test Simulation Program

    NASA Technical Reports Server (NTRS)

    Blumke, R. E.

    1977-01-01

    The objective of the test was to assess fire containment and fire extinguishment in the cargo by reducing the ventilation through the cargo compartment. Parameters which were measured included ignition time, burnthrough time, and physical damage to the cargo liner, composition of selected combustible gases, temperature-time histories, heat flux, and detector response. The ignitor load was made of a typical cargo consisting of filled cardboard cartons occupying 50% of the compartment volume.

  16. Intracellular calcium puffs in osteoclasts.

    PubMed

    Radding, W; Jordan, S E; Hester, R B; Blair, H C

    1999-12-15

    We studied intracellular calcium ([Ca(2+)](i)) in acid-secreting bone-attached osteoclasts, which produce a high-calcium acidic extracellular compartment. Acid secretion and [Ca(2+)](i) were followed using H(+)-restricted dyes and fura-2 or fluo-3. Whole cell calcium of acid-secreting osteoclasts was approximately 100 nM, similar to cells on inert substrate that do not secrete acid. However, measurements in restricted areas of the cell showed [Ca(2+)](i) transients to 500-1000 nM consistent with calcium puffs, transient (millisecond) localized calcium elevations reported in other cells. Spot measurements at 50-ms intervals indicated that puffs were typically less than 400 ms. Transients did not propagate in waves across the cell in scanning confocal measurements. Calcium puffs occurred mainly over regions of acid secretion as determined using lysotracker red DND99 and occurred at irregular periods averaging 5-15 s in acid secreting cells, but were rare in lysotracker-negative nonsecretory cells. The calmodulin antagonist trifluoperazine, cell-surface calcium transport inhibitors lanthanum or barium, and the endoplasmic reticulum ATPase inhibitor thapsigargin had variable acute effects on the mean [Ca(2+)](i) and puff frequency. However, none of these agents prevented calcium puff activity, suggesting that the mechanism producing the puffs is independent of these processes. We conclude that [Ca(2+)](i) transients in osteoclasts are increased in acid-secreting osteoclasts, and that the puffs occur mainly near the acid-transporting membrane. Cell membrane acid transport requires calcium, suggesting that calcium puffs function to maintain acid secretion. However, membrane H(+)-ATPase activity was insensitive to calcium in the 100 nM-1 microM range. Thus, any effects of calcium puffs on osteoclastic acid transport must be indirect.

  17. Intracellular chromium reduction.

    PubMed

    Arslan, P; Beltrame, M; Tomasi, A

    1987-10-22

    Two steps are involved in the uptake of Cr(VI): (1) the diffusion of the anion CrO4(2-) through a facilitated transport system, presumably the non-specific anion carrier and (2) the intracellular reduction of Cr(VI) to Cr(III). The intracellular reduction of Cr(VI), keeping the cytoplasmic concentration of Cr(VI) low, facilitates accumulation of chromate from extracellular medium into the cell. In the present paper, a direct demonstration of intracellular chromium reduction is provided by means of electron paramagnetic (spin) resonance (EPR) spectroscopy. Incubation of metabolically active rat thymocytes with chromate originates a signal which can be attributed to a paramagnetic species of chromium, Cr(V) or Cr(III). The EPR signal is originated by intracellular reduction of chromium since: (1) it is observed only when cells are incubated with chromate, (2) it is present even after extensive washings of the cells in a chromium-free medium; (3) it is abolished when cells are incubated with drugs able to reduce the glutathione pool, i.e., diethylmaleate or phorone; and (4) it is abolished when cells are incubated in the presence of a specific inhibitor of the anion carrier, 4-acetamido-4'-isothiocyanatostilbene-2-2'-disulfonic acid. PMID:2820507

  18. Restricted Location of PSEN2/γ-Secretase Determines Substrate Specificity and Generates an Intracellular Aβ Pool.

    PubMed

    Sannerud, Ragna; Esselens, Cary; Ejsmont, Paulina; Mattera, Rafael; Rochin, Leila; Tharkeshwar, Arun Kumar; De Baets, Greet; De Wever, Veerle; Habets, Roger; Baert, Veerle; Vermeire, Wendy; Michiels, Christine; Groot, Arjan J; Wouters, Rosanne; Dillen, Katleen; Vints, Katlijn; Baatsen, Pieter; Munck, Sebastian; Derua, Rita; Waelkens, Etienne; Basi, Guriqbal S; Mercken, Mark; Vooijs, Marc; Bollen, Mathieu; Schymkowitz, Joost; Rousseau, Frederic; Bonifacino, Juan S; Van Niel, Guillaume; De Strooper, Bart; Annaert, Wim

    2016-06-30

    γ-Secretases are a family of intramembrane-cleaving proteases involved in various signaling pathways and diseases, including Alzheimer's disease (AD). Cells co-express differing γ-secretase complexes, including two homologous presenilins (PSENs). We examined the significance of this heterogeneity and identified a unique motif in PSEN2 that directs this γ-secretase to late endosomes/lysosomes via a phosphorylation-dependent interaction with the AP-1 adaptor complex. Accordingly, PSEN2 selectively cleaves late endosomal/lysosomal localized substrates and generates the prominent pool of intracellular Aβ that contains longer Aβ; familial AD (FAD)-associated mutations in PSEN2 increased the levels of longer Aβ further. Moreover, a subset of FAD mutants in PSEN1, normally more broadly distributed in the cell, phenocopies PSEN2 and shifts its localization to late endosomes/lysosomes. Thus, localization of γ-secretases determines substrate specificity, while FAD-causing mutations strongly enhance accumulation of aggregation-prone Aβ42 in intracellular acidic compartments. The findings reveal potentially important roles for specific intracellular, localized reactions contributing to AD pathogenesis. PMID:27293189

  19. Intracellular trafficking of the pyridoxal cofactor. Implications for health and metabolic disease.

    PubMed

    Whittaker, James W

    2016-02-15

    The importance of the vitamin B6-derived pyridoxal cofactor for human health has been established through more than 70 years of intensive biochemical research, revealing its fundamental roles in metabolism. B6 deficiency, resulting from nutritional limitation or impaired uptake from dietary sources, is associated with epilepsy, neuromuscular disease and neurodegeneration. Hereditary disorders of B6 processing are also known, and genetic defects in pathways involved in transport of B6 into the cell and its transformation to the pyridoxal-5'-phosphate enzyme cofactor can contribute to cardiovascular disease by interfering with homocysteine metabolism and the biosynthesis of vasomodulatory polyamines. Compared to the processes involved in cellular uptake and processing of the B6 vitamers, trafficking of the PLP cofactor across intracellular membranes is very poorly understood, even though the availability of PLP within subcellular compartments (particularly the mitochondrion) may have important health implications. The aim of this review is to concisely summarize the state of current knowledge of intracellular trafficking of PLP and to identify key directions for future research.

  20. Delayed Presentation of Acute Gluteal Compartment Syndrome

    PubMed Central

    Tasch, James J.; Misodi, Emmanuel O.

    2016-01-01

    Patient: Male, 23 Final Diagnosis: Acute gluteal compartment syndrome Symptoms: — Medication: — Clinical Procedure: Gluteal fasciotomy Specialty: Critical Care Medicine Objective: Unusual clinical course Background: Acute gluteal compartment syndrome is a rare condition that usually results from prolonged immobilization following a traumatic event, conventionally involving the presence of compounding factors such as alcohol or opioid intoxication. If delay in medical treatment is prolonged, severe rhabdomyolysis may ensue, leading to acute renal failure and potentially death. Case Report: We report the case of a 23-year-old male with a recent history of incarceration and recreational drug use, who presented with reports of severe right-sided buttock pain and profound right-sided neurological loss following a questionable history involving prolonged immobilization after a fall from a standing position. The patient required an emergent gluteal fasciotomy immediately upon admission and required temporary hemodialysis. After an extended hospital stay, he ultimately recovered with only mild deficits in muscular strength in the right lower extremity. Conclusions: This report demonstrates the importance of early recognition of gluteal compartment syndrome to prevent morbidity and mortality. Compartment syndrome presents in many unique ways, and healthcare practitioners must have a keen diagnostic sense to allow for early surgical intervention. Proper wick catheter measurements should be utilized more frequently, instead of relying on clinical symptomatology such as loss of peripheral pulses for diagnosis of compartment syndrome. PMID:27432320

  1. Exosomes: Tunable Nano Vehicles for Macromolecular Delivery of Transferrin and Lactoferrin to Specific Intracellular Compartment.

    PubMed

    Malhotra, Himanshu; Sheokand, Navdeep; Kumar, Santosh; Chauhan, Anoop S; Kumar, Manoj; Jakhar, Priyanka; Boradia, Vishant M; Raje, Chaaya I; Raje, Manoj

    2016-05-01

    Due to their abundant ubiquitous presence, rapid uptake and increased requirement in neoplastic tissue, the delivery of the iron carrier macromolecules transferrin (Tf) and lactoferrin (Lf) into mammalian cells is the subject of intense interest for delivery of drugs and other target molecules into cells. Utilizing exosomes obtained from cells of diverse origin we confirmed the presence of the multifunctional protein glyceraldehyde-3-phosphate dehydrogenase (GAPDH) which has recently been characterized as a Tf and Lf receptor. Using a combination of biochemical, biophysical and imaging based methodologies, we demonstrate that GAPDH present in exosomes captures Tf and Lf and subsequently effectively delivers these proteins into mammalian cells. Exosome vesicles prepared had a size of 51.2 ± 23.7 nm. They were found to be stable in suspension with a zeta potential (ζ-potential) of -28.16 ± 1.15 mV. Loading of Tf/Lf did not significantly affect ζ-potential of the exosomes. The carrier protein loaded exosomes were able to enhance the delivery of Tf/Lf by 2 to 3 fold in a diverse panel of cell types. Ninety percent of the internalized cargo via this route was found to be specifically delivered into late endosome and lysosomes. We also found exosomes to be tunable nano vehicles for cargo delivery by varying the amount of GAPDH associated with exosome. The current study opens a new avenue of research for efficient delivery of these vital iron carriers into cells employing exosomes as a nano delivery vehicle. PMID:27305829

  2. Exosomes: Tunable Nano Vehicles for Macromolecular Delivery of Transferrin and Lactoferrin to Specific Intracellular Compartment.

    PubMed

    Malhotra, Himanshu; Sheokand, Navdeep; Kumar, Santosh; Chauhan, Anoop S; Kumar, Manoj; Jakhar, Priyanka; Boradia, Vishant M; Raje, Chaaya I; Raje, Manoj

    2016-05-01

    Due to their abundant ubiquitous presence, rapid uptake and increased requirement in neoplastic tissue, the delivery of the iron carrier macromolecules transferrin (Tf) and lactoferrin (Lf) into mammalian cells is the subject of intense interest for delivery of drugs and other target molecules into cells. Utilizing exosomes obtained from cells of diverse origin we confirmed the presence of the multifunctional protein glyceraldehyde-3-phosphate dehydrogenase (GAPDH) which has recently been characterized as a Tf and Lf receptor. Using a combination of biochemical, biophysical and imaging based methodologies, we demonstrate that GAPDH present in exosomes captures Tf and Lf and subsequently effectively delivers these proteins into mammalian cells. Exosome vesicles prepared had a size of 51.2 ± 23.7 nm. They were found to be stable in suspension with a zeta potential (ζ-potential) of -28.16 ± 1.15 mV. Loading of Tf/Lf did not significantly affect ζ-potential of the exosomes. The carrier protein loaded exosomes were able to enhance the delivery of Tf/Lf by 2 to 3 fold in a diverse panel of cell types. Ninety percent of the internalized cargo via this route was found to be specifically delivered into late endosome and lysosomes. We also found exosomes to be tunable nano vehicles for cargo delivery by varying the amount of GAPDH associated with exosome. The current study opens a new avenue of research for efficient delivery of these vital iron carriers into cells employing exosomes as a nano delivery vehicle.

  3. Post-dialysis urea concentration: comparison between one- compartment model and two-compartment model

    NASA Astrophysics Data System (ADS)

    Tamrin, N. S. Ahmad; Ibrahim, N.

    2014-11-01

    The reduction of the urea concentration in blood can be numerically projected by using one-compartment model and two-compartment model with no variation in body fluid. This study aims to compare the simulated values of post-dialysis urea concentration for both models with the clinical data obtained from the hospital. The clinical assessment of adequacy of a treatment is based on the value of Kt/V. Further, direct calculation using clinical data and one-compartment model are presented in the form of ratio. It is found that the ratios of postdialysis urea concentration simulated using two-compartment model are higher compared to the ratios of post-dialysis urea concentration using one-compartment model. In addition, most values of post-dialysis urea concentration simulated using two-compartment model are much closer to the clinical data compared to values simulated using one-compartment model. Kt/V values calculated directly using clinical data are found to be higher than Kt/V values derived from one-compartment model.

  4. 14 CFR 29.855 - Cargo and baggage compartments.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... equipment is not required. (b) No compartment may contain any controls, wiring, lines, equipment, or... to contain compartment fires until a landing and safe evacuation can be made. (d) Each cargo and baggage compartment that is not sealed so as to contain cargo compartment fires completely...

  5. 14 CFR 25.855 - Cargo or baggage compartments.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    .... (e) No compartment may contain any controls, lines, equipment, or accessories whose damage or failure... protective features of the compartment. (g) Sources of heat within the compartment must be shielded and... fire contained in any other compartment, either during or after extinguishment, unless...

  6. Anterior compartment syndrome: a case report.

    PubMed

    Pearl, A J

    1981-01-01

    The chronic form of the anterior compartment syndrome can be overlooked if the symptoms of leg pain are attributed to shin splints. Herein is presented a case report which I feel represents an acute exacerbation of the chronic form of anterior compartment syndrome in a long-distance runner secondary to bleeding into the extensor digitorum longus muscle. Chronic anterior compartment syndrome can be a disabling injury which may require a fasciotomy, depending upon the severity and duration of the patient's symptoms and the intracompartmental pressures. The lay term "shin splints" should be separated from medical use, and a more reliable assessment of the etiology of the patient's symptoms should be made. The term shin splints should be utilized only for pain localized to the posterior medial border of the tibia at the origin of the posterior tibialis muscle.

  7. Chronic exertional compartment syndrome of the leg

    PubMed Central

    2010-01-01

    Chronic exertional compartment syndrome (CECS) is an underdiagnosed cause of chronic exertional leg pain. The syndrome most commonly occurs in young adult recreational runners, elite athletes, and military recruits. CECS is caused by increased intracompartmental pressure within a fascial space; however, the mechanism of why pain occurs is unknown. Symptoms are classically pain in the affected compartment at the same time, distance, or intensity of exercise. CECS is a clinical diagnosis; however, it is confirmed by intracompartmental pressure testing. Fasciotomy is the treatment of choice for athletes who would like to maintain the same level of activity. Athletes who have a release of the anterior and lateral compartments have a high success rate. PMID:21063498

  8. Exercise-induced compartment syndrome: case report.

    PubMed

    Klodell, C T; Pokorny, R; Carrillo, E H; Heniford, B T

    1996-06-01

    Exercise-induced rhabdomyolysis is a frequent event occurring after severe forms of exercise. This is usually a short-lived, uncomplicated phenomenon that is seldom of any clinical significance. The rare progression of this muscle injury to compartment syndrome is, however, a limb- and life-threatening condition that typically presents in the anterior compartment of the lower leg. A case is reported of a young man who participated in physical activity well beyond his normal level of exertion and subsequently developed bilateral lower extremity compartment syndrome requiring surgical decompression. To our knowledge, this is the only description of this complication occurring in a multicompartment, bilateral distribution. The combination of the rarity and morbidity of this condition, as well as the multitude of very common benign injuries that present in the same manner as the problem discussed, make this insult especially dangerous.

  9. [The perichromatin compartment of the cell nucleus].

    PubMed

    Bogoliubov, D S

    2014-01-01

    In this review, the data on the structure and composition of the perichromatin compartment, a special border area between the condensed chromatin and the interchromatin space of the cell nucleus, are discussed in the light of the concept of nuclear functions in complex nuclear architectonics. Morphological features, molecular composition and functions of main extrachromosomal structures of the perichromatin compartment, perichromatin fibrils (PFs) and perichromatin granules (PGs) including nuclear stress-bodies (nSBs) that are derivates of the PGs under heat shock, are presented. A special attention was paid to the features of the molecular compositions of PFs and PGs in different cell types and at different physiological conditions. PMID:25696976

  10. [The perichromatin compartment of the cell nucleus].

    PubMed

    Bogoliubov, D S

    2014-01-01

    In this review, the data on the structure and composition of the perichromatin compartment, a special border area between the condensed chromatin and the interchromatin space of the cell nucleus, are discussed in the light of the concept of nuclear functions in complex nuclear architectonics. Morphological features, molecular composition and functions of main extrachromosomal structures of the perichromatin compartment, perichromatin fibrils (PFs) and perichromatin granules (PGs) including nuclear stress-bodies (nSBs) that are derivates of the PGs under heat shock, are presented. A special attention was paid to the features of the molecular compositions of PFs and PGs in different cell types and at different physiological conditions.

  11. Antibody-Fc receptor interactions in protection against intracellular pathogens.

    PubMed

    Joller, Nicole; Weber, Stefan S; Oxenius, Annette

    2011-04-01

    Intracellular pathogen-specific antibodies (Abs) can contribute to host protection by a number of different mechanisms. Ab opsonization of pathogens residing outside a host cell can prevent infection of target cells either via neutralization of the critical surface epitopes required for host cell entry, complement-mediated degradation, or via subsequent intracellular degradation. In the case of intracellular localization, Abs can bind to infected cells and thus mark them for destruction by Fc receptor (FcR)-bearing effector cells. This review focuses on the protective role of Abs against intracellular bacteria and parasites involving FcR interactions that modulate the intracellular trafficking of the pathogen, the ability of FcRs to interfere with the establishment of an intracellular replicative niche and the involvement of FcRs to modulate pathogen-specific T-cell responses. PMID:21413006

  12. Antibody-Fc receptor interactions in protection against intracellular pathogens.

    PubMed

    Joller, Nicole; Weber, Stefan S; Oxenius, Annette

    2011-04-01

    Intracellular pathogen-specific antibodies (Abs) can contribute to host protection by a number of different mechanisms. Ab opsonization of pathogens residing outside a host cell can prevent infection of target cells either via neutralization of the critical surface epitopes required for host cell entry, complement-mediated degradation, or via subsequent intracellular degradation. In the case of intracellular localization, Abs can bind to infected cells and thus mark them for destruction by Fc receptor (FcR)-bearing effector cells. This review focuses on the protective role of Abs against intracellular bacteria and parasites involving FcR interactions that modulate the intracellular trafficking of the pathogen, the ability of FcRs to interfere with the establishment of an intracellular replicative niche and the involvement of FcRs to modulate pathogen-specific T-cell responses.

  13. Intracellular localization of the Menkes and Wilson's disease proteins and their role in intracellular copper transport.

    PubMed

    Suzuki, M; Gitlin, J D

    1999-08-01

    Copper is a heavy metal ion essential for the activity of a variety of enzymes in the body. In excess, copper is a very toxic ion and therefore efficient regulation of its metabolism is required. This is dramatically illustrated by the genetic disorders X-linked Menkes disease and autosomal recessive Wilson's disease. In 1993, both the Menkes and Wilson's genes were isolated and it was found that these genes encode homologous cation copper transporting P-type ATPase proteins. The Menkes protein (ATP7A) is expressed in most tissues, except liver. In contrast, the Wilson's protein (ATP7B) is abundantly expressed in liver. Intracellular localization of those proteins was investigated. Both ATP7A and ATP7B are localized in the trans-Golgi network and post-Golgi vesicular compartment (PGVC) in the cell. This intracellular localization was altered by the copper content present in the cell. This result may support the hypothesis that ATP7A and ATP7B are involved in cellular copper transport and those proteins could be suitable models for elucidating intracellular copper metabolism.

  14. Intracellular Drug Delivery: Mechanisms for Cell Entry.

    PubMed

    Garnacho, Carmen

    2016-01-01

    Over the last half century, the delivery of pharmacologically active substances, such as synthetic drugs, natural compounds, gene material and many other pharmaceutical products, has been widely studied. Understanding the interactions of drug carriers with cells and how these interactions influence the cellular uptake is of paramount importance, since targets for many therapeutic agents against several disorders are localized in the subcellular compartments. Besides, the route of drug carrier entry (direct or via endocytosis) often defines the efficiency, kinetics and final destination of the drug itself. Although classical endocytic pathways such as phagocytosis, macropinocytosis, clathrin-mediated and caveola-dependent pathways are well characterized, their control for pharmaceutical drug delivery applications is still a challenging issue. Also, better knowledge of non-classical endocytic pathways may help optimize targeted drug delivery systems for intracellular delivery. Therefore, this review focuses on mechanisms of intracellular delivery, including direct internalization and endocytosis, as well as factors such as targeting moiety, target receptor, and size, shape, and surface properties of the drug carrier that can influence uptake process. PMID:26675221

  15. Intracellular Calcium Dysregulation: Implications for Alzheimer's Disease.

    PubMed

    Magi, Simona; Castaldo, Pasqualina; Macrì, Maria Loredana; Maiolino, Marta; Matteucci, Alessandra; Bastioli, Guendalina; Gratteri, Santo; Amoroso, Salvatore; Lariccia, Vincenzo

    2016-01-01

    Alzheimer's Disease (AD) is a neurodegenerative disorder characterized by progressive neuronal loss. AD is associated with aberrant processing of the amyloid precursor protein, which leads to the deposition of amyloid-β plaques within the brain. Together with plaques deposition, the hyperphosphorylation of the microtubules associated protein tau and the formation of intraneuronal neurofibrillary tangles are a typical neuropathological feature in AD brains. Cellular dysfunctions involving specific subcellular compartments, such as mitochondria and endoplasmic reticulum (ER), are emerging as crucial players in the pathogenesis of AD, as well as increased oxidative stress and dysregulation of calcium homeostasis. Specifically, dysregulation of intracellular calcium homeostasis has been suggested as a common proximal cause of neural dysfunction in AD. Aberrant calcium signaling has been considered a phenomenon mainly related to the dysfunction of intracellular calcium stores, which can occur in both neuronal and nonneuronal cells. This review reports the most recent findings on cellular mechanisms involved in the pathogenesis of AD, with main focus on the control of calcium homeostasis at both cytosolic and mitochondrial level. PMID:27340665

  16. Intracellular Calcium Dysregulation: Implications for Alzheimer's Disease

    PubMed Central

    Magi, Simona; Castaldo, Pasqualina; Macrì, Maria Loredana; Maiolino, Marta; Matteucci, Alessandra; Bastioli, Guendalina; Gratteri, Santo; Lariccia, Vincenzo

    2016-01-01

    Alzheimer's Disease (AD) is a neurodegenerative disorder characterized by progressive neuronal loss. AD is associated with aberrant processing of the amyloid precursor protein, which leads to the deposition of amyloid-β plaques within the brain. Together with plaques deposition, the hyperphosphorylation of the microtubules associated protein tau and the formation of intraneuronal neurofibrillary tangles are a typical neuropathological feature in AD brains. Cellular dysfunctions involving specific subcellular compartments, such as mitochondria and endoplasmic reticulum (ER), are emerging as crucial players in the pathogenesis of AD, as well as increased oxidative stress and dysregulation of calcium homeostasis. Specifically, dysregulation of intracellular calcium homeostasis has been suggested as a common proximal cause of neural dysfunction in AD. Aberrant calcium signaling has been considered a phenomenon mainly related to the dysfunction of intracellular calcium stores, which can occur in both neuronal and nonneuronal cells. This review reports the most recent findings on cellular mechanisms involved in the pathogenesis of AD, with main focus on the control of calcium homeostasis at both cytosolic and mitochondrial level. PMID:27340665

  17. Acute and chronic compartment syndromes: know when to act fast.

    PubMed

    McLaughlin, Nancy; Heard, Hank; Kelham, Steven

    2014-06-01

    Compartment syndrome is a fairly common condition noted in patients with fractures or crush injuries to the extremities (acute compartment syndrome) and in athletes (chronic compartment syndrome). Compartments bound by fascia are found in the extremities, buttocks, and abdomen; conditions that cause intracompartmental swelling and hypertension can lead to ischemia and limb loss. This article reviews diagnosis of the problem, monitoring of compartment pressure, and appropriate treatment.

  18. Experimental investigation on the flow around a simplified geometry of automotive engine compartment

    NASA Astrophysics Data System (ADS)

    D'Hondt, Marion; Gilliéron, Patrick; Devinant, Philippe

    2011-05-01

    In the current sustainable development context, car manufacturers have to keep doing efforts to reduce the aerodynamic drag of automotive vehicle in order to decrease their CO2 and greenhouse gas emissions. The cooling airflow, through the engine compartment of vehicles, contributes from 5 to 10% to the total aerodynamic drag. By means of simplified car geometry, equipped with an engine compartment, the configurations that favor a low contribution to total drag are identified. PIV (particle image velocimetry) velocity measurements in the wake of the geometry allow explaining these drag reductions. Besides, the cooling flow rate is also assessed and gives indications on the configurations that favor the engine cooling.

  19. 24 CFR 3280.111 - Toilet compartments.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Toilet compartments. 3280.111 Section 3280.111 Housing and Urban Development Regulations Relating to Housing and Urban Development... URBAN DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Planning Considerations §...

  20. 24 CFR 3280.111 - Toilet compartments.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Toilet compartments. 3280.111 Section 3280.111 Housing and Urban Development Regulations Relating to Housing and Urban Development... URBAN DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Planning Considerations §...

  1. Gluteal Compartment Syndrome Secondary to Pelvic Trauma

    PubMed Central

    Taype Zamboni, Danilo E. R.; Carabelli, Guido S.; Barla, Jorge D.; Sancineto, Carlos F.

    2016-01-01

    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. PMID:27579205

  2. Gluteal Compartment Syndrome Secondary to Pelvic Trauma.

    PubMed

    Diaz Dilernia, Fernando; Zaidenberg, Ezequiel E; Gamsie, Sebastian; Taype Zamboni, Danilo E R; Carabelli, Guido S; Barla, Jorge D; Sancineto, Carlos F

    2016-01-01

    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. PMID:27579205

  3. 24 CFR 3280.111 - Toilet compartments.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... URBAN DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Planning Considerations § 3280.111... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Toilet compartments. 3280.111 Section 3280.111 Housing and Urban Development Regulations Relating to Housing and Urban...

  4. 24 CFR 3280.111 - Toilet compartments.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... URBAN DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Planning Considerations § 3280.111... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Toilet compartments. 3280.111 Section 3280.111 Housing and Urban Development Regulations Relating to Housing and Urban...

  5. Delayed Presentation of Acute Gluteal Compartment Syndrome.

    PubMed

    Tasch, James J; Misodi, Emmanuel O

    2016-01-01

    BACKGROUND Acute gluteal compartment syndrome is a rare condition that usually results from prolonged immobilization following a traumatic event, conventionally involving the presence of compounding factors such as alcohol or opioid intoxication. If delay in medical treatment is prolonged, severe rhabdomyolysis may ensue, leading to acute renal failure and potentially death. CASE REPORT We report the case of a 23-year-old male with a recent history of incarceration and recreational drug use, who presented with reports of severe right-sided buttock pain and profound right-sided neurological loss following a questionable history involving prolonged immobilization after a fall from a standing position. The patient required an emergent gluteal fasciotomy immediately upon admission and required temporary hemodialysis. After an extended hospital stay, he ultimately recovered with only mild deficits in muscular strength in the right lower extremity. CONCLUSIONS This report demonstrates the importance of early recognition of gluteal compartment syndrome to prevent morbidity and mortality. Compartment syndrome presents in many unique ways, and healthcare practitioners must have a keen diagnostic sense to allow for early surgical intervention. Proper wick catheter measurements should be utilized more frequently, instead of relying on clinical symptomatology such as loss of peripheral pulses for diagnosis of compartment syndrome.

  6. Acute bilateral spontaneous forearm compartment syndrome.

    PubMed

    Dalton, David M; Munigangaiah, Sudarshan; Subramaniam, Tava; McCabe, John P

    2014-01-01

    Acute spontaneous compartment syndrome of the forearm is rarely reported in the literature. It is typically associated with trauma or thromboembolism in the acute setting and repetitive exertional stress in the chronic setting. However it is rare for it to present bilaterally with no apparent underlying cause. We report the case of a young 31-year-old lady who presented to our Emergency Department with bilateral compartment syndrome of the forearm. Her presenting complaints included acute severe pain and swelling of the forearms bilaterally, with a decreased range of movement of the wrist and fingers. She also complained of numbness in all fingers. She had no history of recent trauma and ultrasound scans showed no evidence of vascular compromise. Past medical history was notable only for idiopathic hypertension and coeliac disease. The patient was taken to theatre urgently where flexor and extensor compartments and carpal tunnel were decompressed. Pronator Teres was found to be dusky initially but turned pink after decompression. All other muscles were normal. An interesting fact of this case was that combination of the high compartment pressures and anaesthetic related hypotension caused the forearm pulses to become impalpable at induction, these returned intra-operatively. The patient has been seen in the outpatient department following discharge. She is well apart from some mildly reduced grip strength in her right hand likely due to carpal tunnel decompression. No cause was found for the scenario after extensive medical investigation.

  7. Extraocular Muscle Compartments in Superior Oblique Palsy

    PubMed Central

    Suh, Soh Youn; Clark, Robert A.; Le, Alan; Demer, Joseph L.

    2016-01-01

    Purpose To investigate changes in volumes of extraocular muscle (EOM) compartments in unilateral superior oblique (SO) palsy using magnetic resonance imaging (MRI). Methods High-resolution, surface-coil MRI was obtained in 19 patients with unilateral SO palsy and 19 age-matched orthotropic control subjects. Rectus EOMs and the SO were divided into two anatomic compartments for volume analysis in patients with unilateral SO palsy, allowing comparison of total compartmental volumes versus controls. Medial and lateral compartmental volumes of the SO muscle were compared in patients with isotropic (round shape) versus anisotropic (elongated shape) SO atrophy. Results The medial and lateral compartments of the ipsilesional SO muscles were equally atrophic in isotropic SO palsy, whereas the lateral compartment was significantly smaller than the medial in anisotropic SO palsy (P = 0.01). In contrast to the SO, there were no differential compartmental volume changes in rectus EOMs; however, there was significant total muscle hypertrophy in the ipsilesional inferior rectus (IR) and lateral rectus (LR) muscles and contralesional superior rectus (SR) muscles. Medial rectus (MR) volume was normal both ipsi- and contralesionally. Conclusions A subset of patients with SO palsy exhibit selective atrophy of the lateral, predominantly vertically acting SO compartment. Superior oblique atrophy is associated with whole-muscle volume changes in the ipsilesional IR, ipsilesional LR, and contralesional SR; however, SO muscle atrophy is not associated with compartmentally selective volume changes in the rectus EOMs. Selective compartmental SO pathology may provide an anatomic mechanism that explains some of the variability in clinical presentations of SO palsy. PMID:27768791

  8. SERS nanosensors that report pH of endocytic compartments during FcεRI transit

    PubMed Central

    Nowak-Lovato, K.L.; Wilson, Bridget S.; Rector, K.D.

    2011-01-01

    Recently, the development of an IgE receptor (FcεRI)-targeted, pH sensitive, surface-enhanced Raman spectroscopy (SERS) nanosensor has been demonstrated [1]. The targeted nanosensor enables spatial and temporal pH measurements as internalized receptors progress through endosomal compartments in live cells. Trafficking of receptor-bound nanosensors was compared at physiological temperature (37°C) versus room temperature (25°C). As expected, we observed markedly slower progression of receptors through low pH endocytic compartments at the lower temperature. We also demonstrate the utility of the nanosensors to measure directly changes in the pH of intracellular compartments after treatment with bafilomycin or amiloride. We report an increase in endosome compartment pH after treatment with bafilomycin, an H+ ATPase pump inhibitor. Decreased endosomal luminal pH was measured in cells treated with amiloride, an inhibitor of Na+/H+ exchange. The decrease in amiloride-treated cells was transient, followed by a recovery period of approximately 15–20 minutes to restore endosomal pH. These experiments demonstrate the novel application of Raman spectroscopy to monitor local pH environment in live cells with the use of targeted SERS nanosensors. PMID:20842349

  9. High-Throughput Intracellular Antimicrobial Susceptibility Testing of Legionella pneumophila

    PubMed Central

    Chiaraviglio, Lucius

    2015-01-01

    Legionella pneumophila is a Gram-negative opportunistic human pathogen that causes a severe pneumonia known as Legionnaires' disease. Notably, in the human host, the organism is believed to replicate solely within an intracellular compartment, predominantly within pulmonary macrophages. Consequently, successful therapy is predicated on antimicrobials penetrating into this intracellular growth niche. However, standard antimicrobial susceptibility testing methods test solely for extracellular growth inhibition. Here, we make use of a high-throughput assay to characterize intracellular growth inhibition activity of known antimicrobials. For select antimicrobials, high-resolution dose-response analysis was then performed to characterize and compare activity levels in both macrophage infection and axenic growth assays. Results support the superiority of several classes of nonpolar antimicrobials in abrogating intracellular growth. Importantly, our assay results show excellent correlations with prior clinical observations of antimicrobial efficacy. Furthermore, we also show the applicability of high-throughput automation to two- and three-dimensional synergy testing. High-resolution isocontour isobolograms provide in vitro support for specific combination antimicrobial therapy. Taken together, findings suggest that high-throughput screening technology may be successfully applied to identify and characterize antimicrobials that target bacterial pathogens that make use of an intracellular growth niche. PMID:26392509

  10. Application of separable parameter space techniques to multi-tracer PET compartment modeling

    NASA Astrophysics Data System (ADS)

    Zhang, Jeff L.; Morey, A. Michael; Kadrmas, Dan J.

    2016-02-01

    Multi-tracer positron emission tomography (PET) can image two or more tracers in a single scan, characterizing multiple aspects of biological functions to provide new insights into many diseases. The technique uses dynamic imaging, resulting in time-activity curves that contain contributions from each tracer present. The process of separating and recovering separate images and/or imaging measures for each tracer requires the application of kinetic constraints, which are most commonly applied by fitting parallel compartment models for all tracers. Such multi-tracer compartment modeling presents challenging nonlinear fits in multiple dimensions. This work extends separable parameter space kinetic modeling techniques, previously developed for fitting single-tracer compartment models, to fitting multi-tracer compartment models. The multi-tracer compartment model solution equations were reformulated to maximally separate the linear and nonlinear aspects of the fitting problem, and separable least-squares techniques were applied to effectively reduce the dimensionality of the nonlinear fit. The benefits of the approach are then explored through a number of illustrative examples, including characterization of separable parameter space multi-tracer objective functions and demonstration of exhaustive search fits which guarantee the true global minimum to within arbitrary search precision. Iterative gradient-descent algorithms using Levenberg-Marquardt were also tested, demonstrating improved fitting speed and robustness as compared to corresponding fits using conventional model formulations. The proposed technique overcomes many of the challenges in fitting simultaneous multi-tracer PET compartment models.

  11. Acute compartment syndrome of the lower limb and the effect of postoperative analgesia on diagnosis.

    PubMed

    Mar, G J; Barrington, M J; McGuirk, B R

    2009-01-01

    Acute compartment syndrome can cause significant disability if not treated early, but the diagnosis is challenging. This systematic review examines whether modern acute pain management techniques contribute to delayed diagnosis. A total of 28 case reports and case series were identified which referred to the influence of analgesic technique on the diagnosis of compartment syndrome, of which 23 discussed epidural analgesia. In 32 of 35 patients, classic signs and symptoms of compartment syndrome were present in the presence of epidural analgesia, including 18 patients with documented breakthrough pain. There were no randomized controlled trials or outcome-based comparative trials available to include in the review. Pain is often described as the cardinal symptom of compartment syndrome, but many authors consider it unreliable. Physical examination is also unreliable for diagnosis. There is no convincing evidence that patient-controlled analgesia opioids or regional analgesia delay the diagnosis of compartment syndrome provided patients are adequately monitored. Regardless of the type of analgesia used, a high index of clinical suspicion, ongoing assessment of patients, and compartment pressure measurement are essential for early diagnosis.

  12. Overuse injuries: tendinopathies, stress fractures, compartment syndrome, and shin splints.

    PubMed

    Wilder, Robert P; Sethi, Shikha

    2004-01-01

    Approximately 50% of all sports injuries are secondary to overuse and result from repetitive microtrauma that causes local tissue damage. Injuries are most likely with changes in mode, intensity, or duration of training and can accumulate before symptoms appear. Intrinsic factors contributing to injuries are individual bio-mechanical abnormalities such as malalignments, muscle imbalance, inflexibility, weakness, and instability. Contributing extrinsic (avoidable) factors include poor technique, improper equipment, and improper changes in duration or frequency of activity. Injuries are often related to biomechanical abnormalities removed from the specific injury site, requiring evaluation of the entire kinetic chain. This article discusses common overuse injuries of the lower leg, ankle, and foot: tendinopathies, stress fractures, chronic exertional compartment syndrome, and shin splints.

  13. Energy metabolism and intracellular pH in boar spermatozoa.

    PubMed

    Kamp, G; Büsselmann, G; Jones, N; Wiesner, B; Lauterwein, J

    2003-10-01

    The effect of energy metabolism on intracellular pH was studied in boar spermatozoa using nuclear magnetic resonance (NMR) spectroscopy and confocal microscopy with the pH-sensitive dye seminaphthorhodafluor (SNARF-1). Freshly ejaculated spermatozoa had a high adenylate energy charge (AEC=0.8), which decreased to 0.6 under aerobic conditions and to 0.2 under anaerobic conditions. Correspondingly, no ATP resonances but high AMP resonance were visible in (31)P-NMR-spectra of the spermatozoa. When an artificial oxygen buffer (Fluosol) and a purpose-built air supply system were used during (31)P-NMR data acquisition, ATP resonances reappeared whereas the AMP resonance disappeared. Boar spermatozoa kept under aerobic conditions have intracellular compartments that differ markedly in pH, as demonstrated by both (31)P-NMR spectroscopy and confocal microscopy. Using confocal microscopy, the midpiece of the flagellum in which all mitochondria are located was identified as an acidic compartment (pH(i-mp) 6.7). The intracellular pH of both the head (pH(i-h)) and the long principal piece of the flagellum (pH(i-pp)) were 7.2 and, thus, only slightly below the extracellular pH (pH(e) 7.3). Storage of spermatozoa in a glucose-free medium at 15 degrees C when they are immotile slowly shifted the pH(i-mp) from 6.7 to 6.9 within 20 h, whereas pH(i-h) and pH(i-pp) remained unchanged (pH 7.1-7.2). When glucose was present in the medium, all visible compartments of the spermatozoa as well as the medium were acidified to pH 6.2 within 20 h. Under these conditions a resonance at 4.8 mg kg(-1) appeared representing glycerol 3-phosphate.

  14. compartment transfer rates in horizontal flow constructed wetlands

    NASA Astrophysics Data System (ADS)

    Maier, Uli; Oswald, Sascha; Thullner, Martin; Grathwohl, Peter

    2010-05-01

    A conceptual computer model has been constructed to simulate the compartment transfer rates in horizontal flow constructed wetlands. The model accounts for flow and transport in the variably saturated porous medium as well as biogeochemical change reactions. The most concentrated contaminants such as BTEX, MTBE and gasoline hydrocarbons and dissolved as well as mineral phase electron acceptors are considered. Also of major interest are reduced species with high oxygen demand such as ammonium. The influence of marsh plants on microbial activity, gas transport, water balance and contaminant fate in general is matter of current investigation. The constructed wetlands consist of a coarse sand or fine gravel porous medium. Marsh plants were introduced after installation, however, a number of control basins are operated unplanted. Water levels and through flow rates are adjusted to optimize the remediation efficiency. The system is likely to be neither reaction nor mixing limited, thus both, values of dispersivity and degradation kinetics may be crucial for remediation efficiency. Biogeochemical modelling is able to delineate in detail (i) the zonation of processes, (ii) temporal variation (breakthrough curves) and (iii) mass balance information. The contributions of biodegradation and volatilisation and the influence of plants (compartment transfer) can generally best be evaluated by the component's mass balance. More efficient mixing is expected in the wetlands with open water body which leads to both, more biodegradation and volatilisation. An important task is to quantify the role of plants and root systems for contaminant attenuation in constructed wetlands. The long term goal of investigation is to allow for predictions for the design of large scale compartment transfer wetlands that may be applied to remediate the site as a whole.

  15. Determination of intracellular nitrate.

    PubMed Central

    Romero, J M; Lara, C; Guerrero, M G

    1989-01-01

    A sensitive procedure has been developed for the determination of intracellular nitrate. The method includes: (i) preparation of cell lysates in 2 M-H3PO4 after separation of cells from the outer medium by rapid centrifugation through a layer of silicone oil, and (ii) subsequent nitrate analysis by ion-exchange h.p.l.c. with, as mobile phase, a solution containing 50 mM-H3PO4 and 2% (v/v) tetrahydrofuran, adjusted to pH 1.9 with NaOH. The determination of nitrate is subjected to interference by chloride and sulphate when present in the samples at high concentrations. Nitrite also interferes, but it is easily eliminated by treatment of the samples with sulphamic acid. The method has been successfully applied to the study of nitrate transport in the unicellular cyanobacterium Anacystis nidulans. PMID:2497740

  16. Intracellular distribution of differentially phosphorylated dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A).

    PubMed

    Kaczmarski, Wojciech; Barua, Madhabi; Mazur-Kolecka, Bozena; Frackowiak, Janusz; Dowjat, Wieslaw; Mehta, Pankaj; Bolton, David; Hwang, Yu-Wen; Rabe, Ausma; Albertini, Giorgio; Wegiel, Jerzy

    2014-02-01

    The gene encoding dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A) is located within the Down syndrome (DS) critical region of chromosome 21. DYRK1A interacts with a plethora of substrates in the cytosol, cytoskeleton, and nucleus. Its overexpression is a contributing factor to the developmental alterations and age-associated pathology observed in DS. We hypothesized that the intracellular distribution of DYRK1A and cell-compartment-specific functions are associated with DYRK1A posttranslational modifications. Fractionation showed that, in both human and mouse brain, almost 80% of DYRK1A was associated with the cytoskeleton, and the remaining DYRK1A was present in the cytosolic and nuclear fractions. Coimmunoprecipitation revealed that DYRK1A in the brain cytoskeleton fraction forms complexes with filamentous actin, neurofilaments, and tubulin. Two-dimensional gel analysis of the fractions revealed DYRK1A with distinct isoelectric points: 5.5-6.5 in the nucleus, 7.2-8.2 in the cytoskeleton, and 8.7 in the cytosol. Phosphate-affinity gel electrophoresis demonstrated several bands of DYRK1A with different mobility shifts for nuclear, cytoskeletal, and cytosolic DYRK1A, indicating modification by phosphorylation. Mass spectrometry analysis disclosed one phosphorylated site in the cytosolic DYRK1A and multiple phosphorylated residues in the cytoskeletal DYRK1A, including two not previously described. This study supports the hypothesis that intracellular distribution and compartment-specific functions of DYRK1A may depend on its phosphorylation pattern. PMID:24327345

  17. Decompressive laparotomy for abdominal compartment syndrome

    PubMed Central

    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

  18. Actin: its cumbersome pilgrimage through cellular compartments.

    PubMed

    Schleicher, Michael; Jockusch, Brigitte M

    2008-06-01

    In this article, we follow the history of one of the most abundant, most intensely studied proteins of the eukaryotic cells: actin. We report on hallmarks of its discovery, its structural and functional characterization and localization over time, and point to present days' knowledge on its position as a member of a large family. We focus on the rather puzzling number of diverse functions as proposed for actin as a dual compartment protein. Finally, we venture on some speculations as to its origin.

  19. [The anterior compartment syndrome of the leg].

    PubMed

    Parca, S; Tobaldi, F; Palego, E; Galante, V; Bonfili, G F

    1981-09-15

    The Authors define the compartment syndrome as a pathological condition collecting various clinical pictures constantly characterized by a rise of pressure in a restricted and inextensible not modifiable space, with circulatory difficulty and suffering of the tissues in this district. The only diagnosis is clinic. Functional and instrumental semiotics aren't of great aid. The quickly evolving clinical picture commands a timely diagnosis and a precocious intervention to reduce compartmental pressure by fasciotomy and eventual epimysiotomy effectual in the first twelve hours.

  20. Bacterial translocation - impact on the adipocyte compartment.

    PubMed

    Kruis, Tassilo; Batra, Arvind; Siegmund, Britta

    2014-01-01

    Over the last decade it became broadly recognized that adipokines and thus the fat tissue compartment exert a regulatory function on the immune system. Our own group described the pro-inflammatory function of the adipokine leptin within intestinal inflammation in a variety of animal models. Following-up on this initial work, the aim was to reveal stimuli and mechanisms involved in the activation of the fat tissue compartment and the subsequent release of adipokines and other mediators paralleled by the infiltration of immune cells. This review will summarize the current literature on the possible role of the mesenteric fat tissue in intestinal inflammation with a focus on Crohn's disease (CD). CD is of particular interest in this context since the transmural intestinal inflammation has been associated with a characteristic hypertrophy of the mesenteric fat, a phenomenon called "creeping fat." The review will address three consecutive questions: (i) What is inducing adipocyte activation, (ii) which factors are released after activation and what are the consequences for the local fat tissue compartment and infiltrating cells; (iii) do the answers generated before allow for an explanation of the role of the mesenteric fat tissue within intestinal inflammation? With this review we will provide a working model indicating a close interaction in between bacterial translocation, activation of the adipocytes, and subsequent direction of the infiltrating immune cells. In summary, the models system mesenteric fat indicates a unique way how adipocytes can directly interact with the immune system.

  1. The Transmembrane Domain of the Adenovirus E3/19K Protein Acts as an Endoplasmic Reticulum Retention Signal and Contributes to Intracellular Sequestration of Major Histocompatibility Complex Class I Molecules

    PubMed Central

    Sester, Martina; Ruszics, Zsolt; Mackley, Emma

    2013-01-01

    The human adenovirus E3/19K protein is a type I transmembrane glycoprotein of the endoplasmic reticulum (ER) that abrogates cell surface transport of major histocompatibility complex class I (MHC-I) and MHC-I-related chain A and B (MICA/B) molecules. Previous data suggested that E3/19K comprises two functional modules: a luminal domain for interaction with MHC-I and MICA/B molecules and a dilysine motif in the cytoplasmic tail that confers retrieval from the Golgi apparatus back to the ER. This study was prompted by the unexpected phenotype of an E3/19K molecule that was largely retained intracellularly despite having a mutated ER retrieval motif. To identify additional structural determinants responsible for ER localization, chimeric molecules were generated containing the luminal E3/19K domain and the cytoplasmic and/or transmembrane domain (TMD) of the cell surface protein MHC-I Kd. These chimeras were analyzed for transport, cell surface expression, and impact on MHC-I and MICA/B downregulation. As with the retrieval mutant, replacement of the cytoplasmic tail of E3/19K allowed only limited transport of the chimera to the cell surface. Efficient cell surface expression was achieved only by additionally replacing the TMD of E3/19K with that of MHC-I, suggesting that the E3/19K TMD may confer static ER retention. This was verified by ER retention of an MHC-I Kd molecule with the TMD replaced by that of E3/19K. Thus, we have identified the E3/19K TMD as a novel functional element that mediates static ER retention, thereby increasing the concentration of E3/19K in the ER. Remarkably, the ER retrieval signal alone, without the E3/19K TMD, did not mediate efficient HLA downregulation, even in the context of infection. This suggests that the TMD is required together with the ER retrieval function to ensure efficient ER localization and transport inhibition of MHC-I and MICA/B molecules. PMID:23514889

  2. 46 CFR 174.075 - Compartments assumed flooded: general.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Units § 174.075 Compartments assumed flooded: general. The individual flooding of each of the... § 174.065 (a). Simultaneous flooding of more than one compartment must be assumed only when indicated...

  3. 46 CFR 174.075 - Compartments assumed flooded: general.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Units § 174.075 Compartments assumed flooded: general. The individual flooding of each of the... § 174.065 (a). Simultaneous flooding of more than one compartment must be assumed only when indicated...

  4. 46 CFR 174.075 - Compartments assumed flooded: general.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Units § 174.075 Compartments assumed flooded: general. The individual flooding of each of the... § 174.065 (a). Simultaneous flooding of more than one compartment must be assumed only when indicated...

  5. Host metabolism regulates intracellular growth of Trypanosoma cruzi.

    PubMed

    Caradonna, Kacey L; Engel, Juan C; Jacobi, David; Lee, Chih-Hao; Burleigh, Barbara A

    2013-01-16

    Metabolic coupling of intracellular pathogens with host cells is essential for successful colonization of the host. Establishment of intracellular infection by the protozoan Trypanosoma cruzi leads to the development of human Chagas' disease, yet the functional contributions of the host cell toward the infection process remain poorly characterized. Here, a genome-scale functional screen identified interconnected metabolic networks centered around host energy production, nucleotide metabolism, pteridine biosynthesis, and fatty acid oxidation as key processes that fuel intracellular T. cruzi growth. Additionally, the host kinase Akt, which plays essential roles in various cellular processes, was critical for parasite replication. Targeted perturbations in these host metabolic pathways or Akt-dependent signaling pathways modulated the parasite's replicative capacity, highlighting the adaptability of this intracellular pathogen to changing conditions in the host. These findings identify key cellular process regulating intracellular T. cruzi growth and illuminate the potential to leverage host pathways to limit T. cruzi infection. PMID:23332160

  6. Host metabolism regulates intracellular growth of Trypanosoma cruzi

    PubMed Central

    Caradonna, Kacey L.; Engel, Juan C.; Jacobi, David; Lee, Chih-Hao; Burleigh, Barbara A.

    2012-01-01

    SUMMARY Metabolic coupling of intracellular pathogens with host cells is essential for successful colonization of the host. Establishment of intracellular infection by the protozoan Trypanosoma cruzi leads to the development of human Chagas disease, yet the functional contributions of the host cell toward the infection process remain poorly characterized. Here, a genome-scale functional screen identified interconnected metabolic networks centered around host energy production, nucleotide metabolism, pteridine biosynthesis, and fatty acid oxidation as key processes that fuel intracellular T. cruzi growth. Additionally, the host kinase Akt, which plays essential roles in various cellular processes, was critical for parasite replication. Targeted perturbations in these host metabolic pathways or Akt-dependent signaling pathways modulated the parasite’s replicative capacity, highlighting the adaptability of this intracellular pathogen to changing conditions in the host. These findings identify key cellular process regulating intracellular T. cruzi growth and illuminate the potential to leverage host pathways to limit T. cruzi infection. PMID:23332160

  7. Acute compartment syndrome of the thigh following total knee arthroplasty.

    PubMed

    Boonstra, R H; Haverkamp, D; Campo, M M; van der Vis, H M

    2012-03-01

    A 62year old man developed a compartment syndrome of the thigh after total knee arthroplasty. Twelve years previously he had a HTO of the same knee complicated by a compartment syndrome of the calf. The clinical diagnosis was confirmed with intracompartmental pressure measurement. Following fasciotomy pressures were normalized and further course was uncomplicated. Compartment syndrome of the thigh is a rare, but potentially devastating, complication following total knee arthroplasty. A previous compartment syndrome of the calf is identified as a risk factor.

  8. Comparing intracellular stability and targeting of sulfobetaine quantum dots with other surface chemistries in live cells.

    PubMed

    Muro, Eleonora; Fragola, Alexandra; Pons, Thomas; Lequeux, Nicolas; Ioannou, Andriani; Skourides, Paris; Dubertret, Benoit

    2012-04-10

    The in vivo labeling of intracellular components with quantum dots (QDs) is very limited because of QD aggregation in the cell cytoplasm and/or QD confinement into lysosomal compartments. In order to improve intracellular targeting with QDs, various surface chemistries and delivery methods have been explored, but they have not yet been compared systematically with respect to the QD intracellular stability. In this work, the intracellular aggregation kinetics of QDs for three different surface chemistries based on ligand exchange or encapsulation with amphiphilic polymers are compared. For each surface chemistry, three delivery methods for bringing the nanoparticles into the cells are compared: electroporation, microinjection, and pinocytosis. It is concluded that the QD intracellular aggregation behavior is strongly dependent on the surface chemistry. QDs coated with dihydrolipoic acid-sulfobetaine (DHLA-SB) ligands diffuse freely in cells for longer periods of time than for QDs in the other chemistries tested, and they can access all cytoplasmic compartments. Even when conjugated to streptavidin, these DHLA-SB QDs remain freely diffusing inside the cytoplasm and unaggregated, and they are able to reach a biotinylated target inside HeLa cells. Such labeling was more efficient when compared to commercial streptavidin-conjugated QDs, which may be due to the smaller size of DHLA-SB QDs and/or to their superior intracellular stability.

  9. 14 CFR 23.1192 - Engine accessory compartment diaphragm.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Engine accessory compartment diaphragm. 23... Powerplant Powerplant Fire Protection § 23.1192 Engine accessory compartment diaphragm. For aircooled radial... accessory compartment by a diaphragm that meets the firewall requirements of § 23.1191....

  10. 14 CFR 23.1192 - Engine accessory compartment diaphragm.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine accessory compartment diaphragm. 23... Powerplant Powerplant Fire Protection § 23.1192 Engine accessory compartment diaphragm. For aircooled radial... accessory compartment by a diaphragm that meets the firewall requirements of § 23.1191....

  11. 14 CFR 23.1192 - Engine accessory compartment diaphragm.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Engine accessory compartment diaphragm. 23... Powerplant Powerplant Fire Protection § 23.1192 Engine accessory compartment diaphragm. For aircooled radial... accessory compartment by a diaphragm that meets the firewall requirements of § 23.1191....

  12. 14 CFR 23.1192 - Engine accessory compartment diaphragm.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Engine accessory compartment diaphragm. 23... Powerplant Powerplant Fire Protection § 23.1192 Engine accessory compartment diaphragm. For aircooled radial... accessory compartment by a diaphragm that meets the firewall requirements of § 23.1191....

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

    PubMed Central

    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

  14. Chronic exertional compartment syndrome in adductor pollicis muscle: case report.

    PubMed

    Lee, Chang-Hun; Lee, Kwang-Hyun; Lee, Seung-Hun; Kim, Yee-Suk; Chung, Ung-Seo

    2012-11-01

    We report a case of chronic exertional compartment syndrome in the adductor pollicis that was confirmed by measuring elevated compartment pressure. Specific finding of magnetic resonance imaging, increased T2 signal intensity in the involved compartment, was also useful for the diagnosis. Pain was relieved by fasciotomy through a volar approach. PMID:23040640

  15. 14 CFR 27.773 - Pilot compartment view.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Pilot compartment view. 27.773 Section 27... § 27.773 Pilot compartment view. (a) Each pilot compartment must be free from glare and reflections that could interfere with the pilot's view, and designed so that— (1) Each pilot's view is...

  16. 14 CFR 25.772 - Pilot compartment doors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Pilot compartment doors. 25.772 Section 25... § 25.772 Pilot compartment doors. For an airplane that has a lockable door installed between the pilot... pilot compartment if the cockpit door becomes jammed. (c) There must be an emergency means to enable...

  17. 14 CFR 23.773 - Pilot compartment view.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Pilot compartment view. 23.773 Section 23... Personnel and Cargo Accommodations § 23.773 Pilot compartment view. (a) Each pilot compartment must be— (1) Arranged with sufficiently extensive, clear and undistorted view to enable the pilot to safely...

  18. 14 CFR 27.773 - Pilot compartment view.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Pilot compartment view. 27.773 Section 27... § 27.773 Pilot compartment view. (a) Each pilot compartment must be free from glare and reflections that could interfere with the pilot's view, and designed so that— (1) Each pilot's view is...

  19. 14 CFR 23.773 - Pilot compartment view.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Pilot compartment view. 23.773 Section 23... Personnel and Cargo Accommodations § 23.773 Pilot compartment view. (a) Each pilot compartment must be— (1) Arranged with sufficiently extensive, clear and undistorted view to enable the pilot to safely...

  20. 14 CFR 29.773 - Pilot compartment view.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Pilot compartment view. 29.773 Section 29... Accommodations § 29.773 Pilot compartment view. (a) Nonprecipitation conditions. For nonprecipitation conditions, the following apply: (1) Each pilot compartment must be arranged to give the pilots a...

  1. 14 CFR 25.772 - Pilot compartment doors.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Pilot compartment doors. 25.772 Section 25... § 25.772 Pilot compartment doors. For an airplane that has a lockable door installed between the pilot... pilot compartment if the cockpit door becomes jammed. (c) There must be an emergency means to enable...

  2. Resolution of intracellular calcium metabolism in intact segments of rabbit aorta

    SciTech Connect

    Phair, R.D.; Hai, C.M.

    1986-07-01

    A new method, based on computer-assisted kinetic analysis of /sup 45/Ca efflux data, was used to measure calcium contents and fluxes for extracellular and intracellular compartments in intact segments of rabbit aorta. After a 1-hour loading period, efflux data were collected for 8 hours using a flow-through tissue chamber. These long-term effluxes were necessary because information on intracellular calcium metabolism was concentrated in the slow components of the efflux curves while earlier components appeared to be dominated by washout of extracellular calcium. Intracellular compartments were identified as those whose calcium contents were altered by 10 microM phenylephrine. This method complements previous approaches by providing simultaneous estimates of compartmental calcium contents and fluxes without requiring the assumption of isotopic equilibrium and without recourse to standard wash techniques for removal of extracellular calcium. In normal, calcium-containing, bicarbonate-buffered physiological salt solution these compartments contained a total of approximately 300 nmol Ca/g wet aorta. Of this total, 55 nmol/g were associated with the slowest resolvable compartment whose turnover time was 170 minutes and whose exchange flux was 0.32 nmol min-1g-1. Two other intracellular compartments had turnover times of 30 minutes. One of these was phenylephrine releasable and contained 145 nmol/g; it exchanged calcium at 4.9 nmol min-1g-1. In normal physiological salt solution the plasma membrane was, surprisingly, not rate limiting for Ca efflux; and in 10 microM phenylephrine the membrane Ca flux was even greater, increasing 3.5-fold compared to control.

  3. Nutrient salvaging and metabolism by the intracellular pathogen Legionella pneumophila

    PubMed Central

    Fonseca, Maris V.; Swanson, Michele S.

    2014-01-01

    The Gram-negative bacterium Legionella pneumophila is ubiquitous in freshwater environments as a free-swimming organism, resident of biofilms, or parasite of protozoa. If the bacterium is aerosolized and inhaled by a susceptible human host, it can infect alveolar macrophages and cause a severe pneumonia known as Legionnaires' disease. A sophisticated cell differentiation program equips L. pneumophila to persist in both extracellular and intracellular niches. During its life cycle, L. pneumophila alternates between at least two distinct forms: a transmissive form equipped to infect host cells and evade lysosomal degradation, and a replicative form that multiplies within a phagosomal compartment that it has retooled to its advantage. The efficient changeover between transmissive and replicative states is fundamental to L. pneumophila's fitness as an intracellular pathogen. The transmission and replication programs of L. pneumophila are governed by a number of metabolic cues that signal whether conditions are favorable for replication or instead trigger escape from a spent host. Several lines of experimental evidence gathered over the past decade establish strong links between metabolism, cellular differentiation, and virulence of L. pneumophila. Herein, we focus on current knowledge of the metabolic components employed by intracellular L. pneumophila for cell differentiation, nutrient salvaging and utilization of host factors. Specifically, we highlight the metabolic cues that are coupled to bacterial differentiation, nutrient acquisition systems, and the strategies utilized by L. pneumophila to exploit host metabolites for intracellular replication. PMID:24575391

  4. Acute compartment syndrome of the thigh secondary to isolated common femoral vessel injury: an unusual etiology.

    PubMed

    Davaine, Jean-Michel; Lintz, François; Cappelli, Marc; Chaillou, Philippe; Gouin, François; Patra, Philippe; Gouëffic, Yann

    2013-08-01

    We report a case of acute compartment syndrome of the thigh secondary to common femoral vessel injury. The lesion was associated with common femoral artery dissection and common femoral vein rupture. Emergency surgical treatment consisted of resection-anastomosis of the arterial dissection, vein ligature, and fasciotomies. The patient is symptom-free after 15 months of follow-up. Isolated vascular injury is an unusual cause of acute compartment syndrome of the thigh. This case serves to increase awareness that isolated vascular injury, without femoral fracture or multiple injury, can result in thigh compartment syndrome. Early recognition and treatment of vascular involvement contributes to better functional outcome of this rare condition, but treatment modalities remain subject to discussion.

  5. Mechanisms of intracellular ice formation.

    PubMed Central

    Muldrew, K; McGann, L E

    1990-01-01

    The phenomenon of intracellular freezing in cells was investigated by designing experiments with cultured mouse fibroblasts on a cryomicroscope to critically assess the current hypotheses describing the genesis of intracellular ice: (a) intracellular freezing is a result of critical undercooling; (b) the cytoplasm is nucleated through aqueous pores in the plasma membrane; and (c) intracellular freezing is a result of membrane damage caused by electrical transients at the ice interface. The experimental data did not support any of these theories, but was consistent with the hypothesis that the plasma membrane is damaged at a critical gradient in osmotic pressure across the membrane, and intracellular freezing occurs as a result of this damage. An implication of this hypothesis is that mathematical models can be used to design protocols to avoid damaging gradients in osmotic pressure, allowing new approaches to the preservation of cells, tissues, and organs by rapid cooling. PMID:2306499

  6. Exercise induced compartment syndrome in a professional footballer.

    PubMed

    Cetinus, E; Uzel, M; Bilgiç, E; Karaoguz, A; Herdem, M

    2004-04-01

    Recurrent pain in the lower leg caused by exercise is a common problem in athletes. The main causes are exercise induced compartment syndrome, periostitis of the tibia, stress fracture, venous diseases, obliterative arterial diseases, and shin splints. Exercise induced compartment syndrome is the least common. A recurrent tightening or tense sensation and aching in anatomically defined compartments is pathognomonic. The symptoms are caused by abnormally high pressure in compartments of the leg during and after exercise. In this report, a case of exercise induced compartment syndrome in a professional footballer is described.

  7. Microspectroscopy of the photosynthetic compartment of algae.

    PubMed

    Evangelista, Valtere; Frassanito, Anna Maria; Passarelli, Vincenzo; Barsanti, Laura; Gualtieri, Paolo

    2006-01-01

    We performed microspectroscopic evaluation of the pigment composition of the photosynthetic compartments of algae belonging to different taxonomic divisions and higher plants. The feasibility of microspectroscopy for discriminating among species and/or phylogenetic groups was tested on laboratory cultures. Gaussian bands decompositions and a fitting algorithm, together with fourth-derivative transformation of absorbance spectra, provided a reliable discrimination among chlorophylls a, b and c, phycobiliproteins and carotenoids. Comparative analysis of absorption spectra highlighted the evolutionary grouping of the algae into three main lineages in accordance with the most recent endosymbiotic theories.

  8. Ultrasonic Apparatus and Method to Assess Compartment Syndrome

    NASA Technical Reports Server (NTRS)

    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.

  9. Acute compartment syndrome of the leg: pressure measurement and fasciotomy.

    PubMed

    Masquelet, A-C

    2010-12-01

    Compartment syndrome involves a conflicting situation between an unyielding space, the compartment, and its increasing tissue content secondary to traumatic ischemia. Rapidly irreversible damages occur without treatment. Although the diagnosis approach to leg compartment syndrome is clinical in priority, pressure measurements should be systematically produced: first to confirm the presence of this condition and define optimal surgical strategies and second to provide the only objective available criteria in case of a debatable diagnosis. In practice, two schematic situations can be distinguished, which do not cover the many different cases: leg compartment syndrome without a fracture in which the four leg compartments are affected and which requires a fasciotomy using two surgical approaches, the lateral and the medial; leg compartment syndrome associated with a fracture: fasciotomy of the four compartments may be performed by a single lateral approach distant from the fracture site and its fixation hardware. It should be noted that this approach is easy, effective and safe.

  10. Ionic milieu controls the compartment-specific activation of pro-opiomelanocortin processing in AtT-20 cells.

    PubMed Central

    Schmidt, W K; Moore, H P

    1995-01-01

    Newly synthesized prohormones and their processing enzymes transit through the same compartments before being packaged into regulated secretory granules. Despite this coordinated intracellular transport, prohormone processing does not occur until late in the secretory pathway. In the mouse pituitary AtT-20 cell line, conversion of pro-opiomelanocortin (POMC) to mature adrenocorticotropic hormone involves the prohormone convertase PC1. The mechanism by which this proteolytic processing is restricted to late secretory compartments is unknown; PC1 activity could be regulated by compartment-specific activators/inhibitors, or through changes in the ionic milieu that influence its activity. By arresting transport in a semi-intact cell system, we have addressed whether metabolically labeled POMC trapped in early secretory compartments can be induced to undergo conversion if the ionic milieu in these compartments is experimentally manipulated. Prolonged incubation of labeled POMC trapped in the endoplasmic reticulum or Golgi/trans-Golgi network did not result in processing, thereby supporting the theory that processing is normally a post-Golgi/trans-Golgi network event. However, acidification of these compartments allowed effective processing of POMC to the intermediate and mature forms. The observed processing increased sharply at a pH below 6.0 and required millimolar calcium, regardless of the compartment in which labeled POMC resided. These conditions also resulted in the coordinate conversion of PC1 from the 84/87 kDa into the 74-kDa and 66-kDa forms. We propose that POMC processing is predominantly restricted to acidifying secretory granules, and that a change in pH within these granules is both necessary and sufficient to activate POMC processing. Images PMID:8573786

  11. Intracellular events regulating cross-presentation

    PubMed Central

    Wagner, Claudia S.; Grotzke, Jeffrey E.; Cresswell, Peter

    2012-01-01

    Cross-presentation plays a fundamental role in the induction of CD8-T cell immunity. However, although more than three decades have passed since its discovery, surprisingly little is known about the exact mechanisms involved. Here we give an overview of the components involved at different stages of this process. First, antigens must be internalized into the cross-presenting cell. The involvement of different receptors, method of antigen uptake, and nature of the antigen can influence intracellular trafficking and access to the cross-presentation pathway. Once antigens access the endocytic system, different requirements for endosomal/phagosomal processing arise, such as proteolysis and reduction of disulfide bonds. The majority of cross-presented peptides are generated by proteasomal degradation. Therefore, antigens must cross a membrane barrier in a manner analogous to the fate of misfolded proteins in the endoplasmic reticulum (ER) that are retrotranslocated into the cytosol for degradation. Indeed, some components of the ER-associated degradation machinery have been implicated in cross-presentation. Further complicating the matter, endosomal and phagosomal compartments have been suggested as alternative sites to the ER for loading of peptides on major histocompatibility complex class I molecules. Finally, the antigen presenting cells involved, particularly dendritic cell subsets and their state of maturation, influence the efficiency of cross-presentation. PMID:22675326

  12. Determination of Intracellular Vitrification Temperatures for Unicellular Micro Organisms under Conditions Relevant for Cryopreservation.

    PubMed

    Fonseca, Fernanda; Meneghel, Julie; Cenard, Stéphanie; Passot, Stéphanie; Morris, G John

    2016-01-01

    During cryopreservation ice nucleation and crystal growth may occur within cells or the intracellular compartment may vitrify. Whilst previous literature describes intracellular vitrification in a qualitative manner, here we measure the intracellular vitrification temperature of bacteria and yeasts under conditions relevant to cryopreservation, including the addition of high levels of permeating and nonpermeating additives and the application of rapid rates of cooling. The effects of growth conditions that are known to modify cellular freezing resistance on the intracellular vitrification temperature are also examined. For bacteria a plot of the activity on thawing against intracellular glass transition of the maximally freeze-concentrated matrix (Tg') shows that cells with the lowest value of intracellular Tg' survive the freezing process better than cells with a higher intracellular Tg'. This paper demonstrates the role of the physical state of the intracellular environment in determining the response of microbial cells to preservation and could be a powerful tool to be manipulated to allow the optimization of methods for the preservation of microorganisms. PMID:27055246

  13. Determination of Intracellular Vitrification Temperatures for Unicellular Micro Organisms under Conditions Relevant for Cryopreservation

    PubMed Central

    Fonseca, Fernanda; Meneghel, Julie; Cenard, Stéphanie; Passot, Stéphanie; Morris, G. John

    2016-01-01

    During cryopreservation ice nucleation and crystal growth may occur within cells or the intracellular compartment may vitrify. Whilst previous literature describes intracellular vitrification in a qualitative manner, here we measure the intracellular vitrification temperature of bacteria and yeasts under conditions relevant to cryopreservation, including the addition of high levels of permeating and nonpermeating additives and the application of rapid rates of cooling. The effects of growth conditions that are known to modify cellular freezing resistance on the intracellular vitrification temperature are also examined. For bacteria a plot of the activity on thawing against intracellular glass transition of the maximally freeze-concentrated matrix (Tg’) shows that cells with the lowest value of intracellular Tg’ survive the freezing process better than cells with a higher intracellular Tg’. This paper demonstrates the role of the physical state of the intracellular environment in determining the response of microbial cells to preservation and could be a powerful tool to be manipulated to allow the optimization of methods for the preservation of microorganisms. PMID:27055246

  14. The Francisella tularensis migR, trmE, and cphA Genes Contribute to F. tularensis Pathogenicity Island Gene Regulation and Intracellular Growth by Modulation of the Stress Alarmone ppGpp

    PubMed Central

    Faron, Matthew; Fletcher, Joshua R.; Rasmussen, Jed A.; Long, Matthew E.; Allen, Lee-Ann H.

    2013-01-01

    The Francisella tularensis pathogenicity island (FPI) encodes many proteins that are required for virulence. Expression of these genes depends upon the FevR (PigR) regulator and its interactions with the MglA/SspA and RNA polymerase transcriptional complex. Experiments to identify how transcription of the FPI genes is activated have led to identification of mutations within the migR, trmE, and cphA genes that decrease FPI expression. Recent data demonstrated that the small alarmone ppGpp, produced by RelA and SpoT, is important for stabilizing MglA/SspA and FevR (PigR) interactions in Francisella. Production of ppGpp is commonly known to be activated by cellular and nutritional stress in bacteria, which indicates that cellular and nutritional stresses act as important signals for FPI activation. In this work, we demonstrate that mutations in migR, trmE, or cphA significantly reduce ppGpp accumulation. The reduction in ppGpp levels was similar for each of the mutants and correlated with a corresponding reduction in iglA reporter expression. In addition, we observed that there were differences in the ability of each of these mutants to replicate within various mammalian cells, indicating that the migR, trmE, and cphA genes are likely parts of different cellular stress response pathways in Francisella. These results also indicate that different nutritional and cellular stresses exist in different mammalian cells. This work provides new information to help understand how Francisella regulates its virulence genes in response to host cell environments, and it contributes to our growing knowledge of this highly successful bacterial pathogen. PMID:23716606

  15. The Francisella tularensis migR, trmE, and cphA genes contribute to F. tularensis pathogenicity island gene regulation and intracellular growth by modulation of the stress alarmone ppGpp.

    PubMed

    Faron, Matthew; Fletcher, Joshua R; Rasmussen, Jed A; Long, Matthew E; Allen, Lee-Ann H; Jones, Bradley D

    2013-08-01

    The Francisella tularensis pathogenicity island (FPI) encodes many proteins that are required for virulence. Expression of these genes depends upon the FevR (PigR) regulator and its interactions with the MglA/SspA and RNA polymerase transcriptional complex. Experiments to identify how transcription of the FPI genes is activated have led to identification of mutations within the migR, trmE, and cphA genes that decrease FPI expression. Recent data demonstrated that the small alarmone ppGpp, produced by RelA and SpoT, is important for stabilizing MglA/SspA and FevR (PigR) interactions in Francisella. Production of ppGpp is commonly known to be activated by cellular and nutritional stress in bacteria, which indicates that cellular and nutritional stresses act as important signals for FPI activation. In this work, we demonstrate that mutations in migR, trmE, or cphA significantly reduce ppGpp accumulation. The reduction in ppGpp levels was similar for each of the mutants and correlated with a corresponding reduction in iglA reporter expression. In addition, we observed that there were differences in the ability of each of these mutants to replicate within various mammalian cells, indicating that the migR, trmE, and cphA genes are likely parts of different cellular stress response pathways in Francisella. These results also indicate that different nutritional and cellular stresses exist in different mammalian cells. This work provides new information to help understand how Francisella regulates its virulence genes in response to host cell environments, and it contributes to our growing knowledge of this highly successful bacterial pathogen.

  16. Remote detection of pressure compartments. Topical report

    SciTech Connect

    Surdam, R.C.; Boyd, N.; Jiao, Z.; Maucione, D.; Kubicheck, S.

    1996-02-01

    A significant portion of the Cretaceous shale section in the Rocky Mountain Laramide Basins (RMLB) is anomalously pressured and gas saturated. The top of the anomalously pressured zone is identified by marked increases in sonic transit time, hydrocarbon production index (P.I.), clay diagenesis (smectite to illite), and vitrinite reflectance gradients. The driving mechanism of anomalous pressure development and compartmentalization is the generation and storage of liquid hydrocarbons that subsequently partially react to gas, converting the fluid-flow system to a multiphase regime in which capillarity controls permeability; the result is elevated displacement pressure within the shales. Sandstone reservoirs within this anomalously pressured shale section are subdivided stratigraphically and diagenetically into relatively small, isolated pressure or fluid-flow compartments. The saturation of these compartments with hydrocarbons and the subsequent oil-to-gas reaction causes explusion of a significant portion of the free water, resulting in anomalously pressured gas accumulations characterized by depletion drive. The determination of the position and configuration of the pressure boundary between normal and anomalously pressured regimes and the detection and delineation of porosity/permeability `sweet spots` below this boundary are the two most important elements in exploring for basin center gas in the RMLB.

  17. Analysis of body water compartments after a short sauna bath using bioelectric impedance analysis.

    PubMed

    Servidio, M-F; Mohamed, E I; Maiolo, C; Hereba, A T; Perrone, F; Garofano, P; Iacopino, L

    2003-10-01

    Studies have suggested that long-term sauna bathing may lower blood pressure in persons with hypertension by causing a direct loss of extracellular water and plasma minerals. The objective of the present study was to evaluate the effect of short-term sauna bathing on body water compartments as estimated by bioelectric impedance analysis (BIA). We recruited 15 men [mean age (+/-SD) of 23.93+/-5.12 years and mean body mass index (BMI) of 23.25+/-2.84 kg/m(2)] and 10 women matched for age and BMI. Total body resistance, reactance, and impedance were measured for all participants using BIA, at baseline, after a short sauna bath, and after a rest period. Total, extracellular, and intracellular water compartments were calculated using BIA formulae. There were no significant differences for any of the body water compartments when comparing the measurements taken before and after the sauna bath and after the rest period. However, it remains to be determined whether or not BIA is sensitive to rapid changes in water volume.

  18. Some thoughts about the intracellular location of nanoparticles and the resulting consequences.

    PubMed

    Rejman, Joanna; Nazarenus, Moritz; Jimenez de Aberasturi, Dorleta; Said, Alaa Hassan; Feliu, Neus; Parak, Wolfgang J

    2016-11-15

    It is qualitatively demonstrated that the intracellular localization of particles depends on the way they are administered, their basic physicochemical properties, as well as on incubation time. For this purpose cells were exposed to fluorescently-labelled particles of different size under different exposure scenarios including incubation, microinjection, electroporation, and sonoporation. After co-exposure to cells the intracellular distribution of different particles was imaged with multicolor fluorescence microscopy. Qualitative co-localization analysis demonstrates, that different particles to which cells have been exposed in different ways did not automatically reside in the same compartment. As intracellular particle localization may influence potential toxic effects of particles on cells, studies attempting to unravel molecular mechanisms of toxicity should involve the determination of the intracellular particle distribution. PMID:27572895

  19. Depollution potential of three macrophytes: exudated, wall-bound and intracellular peroxidase activities plus intracellular phenol concentrations.

    PubMed

    Larue, Camille; Korboulewsky, Nathalie; Wang, Runying; Mévy, Jean-Philippe

    2010-10-01

    The aim of this study was to investigate the potential role of three macrophyte species (Iris pseudacorus, Typha latifolia and Phragmites australis) for detoxication of xenobiotics, and to study their variations with seasons or concentrations of sewage sludge from the food industry. For this purpose, some aspects of the green liver concept were explored through peroxidase measurements in three compartments in roots: intracellular, cell wall and extracellular. In addition, phenol concentrations were also measured in order to assess heavy metal detoxication potential. Enzyme activities and phenol concentrations were overall lower in winter according to the phenological stages and some sludge effects occurred. Results show that P. australis roots exuded and contained more peroxidase in all seasons: 17 U/g (1373 U/g protein), 0.8 U/g (613 U/g protein) and 4.8 U/g (1329 U/g protein) in intracellular compartments, cell wall and exudates, respectively. In contrast, the highest phenol concentration was found in I. pseudacorus roots: 3.58 mg eq. [corrected] gallic acid/g. Hence, in constructed wetlands, P. australis is suitable for organic waste water treatment, while I. pseudacorus should be used in the case of waters highly charged with heavy metals.

  20. Multifaceted plasma membrane Ca(2+) pumps: From structure to intracellular Ca(2+) handling and cancer.

    PubMed

    Padányi, Rita; Pászty, Katalin; Hegedűs, Luca; Varga, Karolina; Papp, Béla; Penniston, John T; Enyedi, Ágnes

    2016-06-01

    Plasma membrane Ca(2+) ATPases (PMCAs) are intimately involved in the control of intracellular Ca(2+) concentration. They reduce Ca(2+) in the cytosol not only by direct ejection, but also by controlling the formation of inositol-1,4,5-trisphosphate and decreasing Ca(2+) release from the endoplasmic reticulum Ca(2+) pool. In mammals four genes (PMCA1-4) are expressed, and alternative RNA splicing generates more than twenty variants. The variants differ in their regulatory characteristics. They localize into highly specialized membrane compartments and respond to the incoming Ca(2+) with distinct temporal resolution. The expression pattern of variants depends on cell type; a change in this pattern can result in perturbed Ca(2+) homeostasis and thus altered cell function. Indeed, PMCAs undergo remarkable changes in their expression pattern during tumorigenesis that might significantly contribute to the unbalanced Ca(2+) homeostasis of cancer cells. This article is part of a Special Issue entitled: Calcium and Cell Fate. Guest Editors: Jacques Haiech, Claus Heizmann, Joachim Krebs, Thierry Capiod and Olivier Mignen. PMID:26707182

  1. ATP stimulates pannexin 1 internalization to endosomal compartments.

    PubMed

    Boyce, Andrew K J; Kim, Michelle S; Wicki-Stordeur, Leigh E; Swayne, Leigh Anne

    2015-09-15

    The ubiquitous pannexin 1 (Panx1) ion- and metabolite-permeable channel mediates the release of ATP, a potent signalling molecule. In the present study, we provide striking evidence that ATP, in turn, stimulates internalization of Panx1 to intracellular membranes. These findings hold important implications for understanding the regulation of Panx1 when extracellular ATP is elevated. In the nervous system, this includes phenomena such as synaptic plasticity, pain, precursor cell development and stroke; outside of the nervous system, this includes things like skeletal and smooth muscle activity and inflammation. Within 15 min, ATP led to significant Panx1-EGFP internalization. In a series of experiments, we determined that hydrolysable ATP is the most potent stimulator of Panx1 internalization. We identified two possible mechanisms for Panx1 internalization, including activation of ionotropic purinergic (P2X) receptors and involvement of a putative ATP-sensitive residue in the first extracellular loop of Panx1 (Trp(74)). Internalization was cholesterol-dependent, but clathrin, caveolin and dynamin independent. Detailed analysis of Panx1 at specific endosome sub-compartments confirmed that Panx1 is expressed in endosome membranes of the classical degradation pathway under basal conditions and that elevation of ATP levels diverts a sub-population to recycling endosomes. This is the first report detailing endosome localization of Panx1 under basal conditions and the potential for ATP regulation of its surface expression. Given the ubiquitous expression profile of Panx1 and the importance of ATP signalling, these findings are of critical importance for understanding the role of Panx1 in health and disease. PMID:26195825

  2. ATP stimulates pannexin 1 internalization to endosomal compartments.

    PubMed

    Boyce, Andrew K J; Kim, Michelle S; Wicki-Stordeur, Leigh E; Swayne, Leigh Anne

    2015-09-15

    The ubiquitous pannexin 1 (Panx1) ion- and metabolite-permeable channel mediates the release of ATP, a potent signalling molecule. In the present study, we provide striking evidence that ATP, in turn, stimulates internalization of Panx1 to intracellular membranes. These findings hold important implications for understanding the regulation of Panx1 when extracellular ATP is elevated. In the nervous system, this includes phenomena such as synaptic plasticity, pain, precursor cell development and stroke; outside of the nervous system, this includes things like skeletal and smooth muscle activity and inflammation. Within 15 min, ATP led to significant Panx1-EGFP internalization. In a series of experiments, we determined that hydrolysable ATP is the most potent stimulator of Panx1 internalization. We identified two possible mechanisms for Panx1 internalization, including activation of ionotropic purinergic (P2X) receptors and involvement of a putative ATP-sensitive residue in the first extracellular loop of Panx1 (Trp(74)). Internalization was cholesterol-dependent, but clathrin, caveolin and dynamin independent. Detailed analysis of Panx1 at specific endosome sub-compartments confirmed that Panx1 is expressed in endosome membranes of the classical degradation pathway under basal conditions and that elevation of ATP levels diverts a sub-population to recycling endosomes. This is the first report detailing endosome localization of Panx1 under basal conditions and the potential for ATP regulation of its surface expression. Given the ubiquitous expression profile of Panx1 and the importance of ATP signalling, these findings are of critical importance for understanding the role of Panx1 in health and disease.

  3. INTRACELLULAR SIGNALING AND DEVELOPMENTAL NEUROTOXICITY.

    EPA Science Inventory

    A book chapter in ?Molecular Toxicology: Transcriptional Targets? reviewed the role of intracellular signaling in the developmental neurotoxicity of environmental chemicals. This chapter covered a number of aspects including the development of the nervous system, role of intrace...

  4. [Intestinal occlusion and abdominal compartment syndrome (ACS)].

    PubMed

    Stagnitti, Franco

    2009-01-01

    Intestinal occlusion is defined as an independent predictive factor of intra-abdominal hypertension (IAH) which represents an independent predictor of mortality. Baggot in 1951 classified patients operated with intestinal occlusion as being at risk for IAH ("abdominal blow-out"), recommending them for open abdomen surgery proposed by Ogilvie. Abdominal surgery provokes IAH in 44.7% of cases with mortality which, in emergency, triples with respect to elective surgery (21.9% vs 6.8%). In particular, IAH is present in 61.2% of ileus and bowel distension and is responsible for 52% of mortality (54.8% in cases with intra-abdominal infection). These patients present with an increasing intra-abdominal pressure (IAP) which, over 20-25 mmHg, triggers an Abdominal Compartment Syndrome (ACS) with altered functions in some organs arriving at Multiple Organ Dysfunction Syndrome (MODS). The intestine normally covers 58% of abdominal volume but when there is ileus distension, intestinal pneumatosis develops (third space) which can occupy up to 90% of the entire cavity. At this moment, Gastro Intestinal Failure (GIF) can appear, which is a specific independent risk factor of mortality, motor of "Organ Failure". The pathophysiological evolution has many factors in 45% of cases: intestinal pneumatosis is associated with mucosal and serous edema, capillary leakage with an increase in extra-cellular volume and peritoneal fluid collections (fourth space). The successive loss of the mucous barrier permits a bacterial translocation which includes bacteria, toxins, pro-inflammatory factors and oxygen free radicals facilitating the passage from an intra-abdominal to inter-systemic vicious cyrcle. IAH provokes the raising of the diaphragm, and vascular and visceral compressions which induce hypertension in the various spaces with compartmental characteristics. These trigger hypertension in the renal, hepatic, pelvic, thoracic, cardiac, intracranial, orbital and lower extremity areas, giving

  5. Extracellular Matrix Stiffness and Architecture Govern Intracellular Rheology in Cancer

    PubMed Central

    Baker, Erin L.; Bonnecaze, Roger T.; Zaman, Muhammad H.

    2009-01-01

    Abstract Little is known about the complex interplay between the extracellular mechanical environment and the mechanical properties that characterize the dynamic intracellular environment. To elucidate this relationship in cancer, we probe the intracellular environment using particle-tracking microrheology. In three-dimensional (3D) matrices, intracellular effective creep compliance of prostate cancer cells is shown to increase with increasing extracellular matrix (ECM) stiffness, whereas modulating ECM stiffness does not significantly affect the intracellular mechanical state when cells are attached to two-dimensional (2D) matrices. Switching from 2D to 3D matrices induces an order-of-magnitude shift in intracellular effective creep compliance and apparent elastic modulus. However, for a given matrix stiffness, partial blocking of β1 integrins mitigates the shift in intracellular mechanical state that is invoked by switching from a 2D to 3D matrix architecture. This finding suggests that the increased cell-matrix engagement inherent to a 3D matrix architecture may contribute to differences observed in viscoelastic properties between cells attached to 2D matrices and cells embedded within 3D matrices. In total, our observations show that ECM stiffness and architecture can strongly influence the intracellular mechanical state of cancer cells. PMID:19686648

  6. Designing the Space Station Crew Compartment

    NASA Astrophysics Data System (ADS)

    Kitmacher, Gary

    2002-01-01

    Design of the crew compartment in the modules of the International Space Station began in the mid-1980s and was influenced by past experiences as well as new and innovative designs. This paper will trace some of the alternative configurations that were considered during the early Phase B studies and the trade studies, design and modeling activities which led to the configuration as it is being flown today. Design of the core systems, lofts, and rack-based modules will all be reviewed. Based upon crew feedback and experiences in the integration of space station missions over the years of operation, problems that have been experienced in planning and implementation will be reviewed.

  7. The Orbital Workshop Waste Management Compartment

    NASA Technical Reports Server (NTRS)

    1972-01-01

    This image is a wide-angle view of the Orbital Workshop waste management compartment. The waste management facilities presented a unique challenge to spacecraft designers. In addition to collection of liquid and solid human wastes, there was a medical requirement to dry all solid human waste products and to return the residue to Earth for examination. Liquid human waste (urine) was frozen for return to Earth. Total quantities of each astronaut's liquid and solid wastes were precisely measured. Cabin air was drawn into the toilet, shown on the wall at right in this photograph, and over the waste products to generate a flow of the waste in the desired direction. The air was then filtered for odor control and antiseptic purposes prior to being discharged back into the cabin.

  8. cAMP signalling meets mitochondrial compartments.

    PubMed

    Lefkimmiatis, Konstantinos

    2014-04-01

    Mitochondria are highly dynamic organelles comprising at least three distinct areas, the OMM (outer mitochondrial membrane), the IMS (intermembrane space) and the mitochondrial matrix. Physical compartmentalization allows these organelles to host different functional domains and therefore participate in a variety of important cellular actions such as ATP synthesis and programmed cell death. In a surprising homology, it is now widely accepted that the ubiquitous second messenger cAMP uses the same stratagem, compartmentalization, in order to achieve the characteristic functional pleiotropy of its pathway. Accumulating evidence suggests that all the main mitochondrial compartments contain segregated cAMP cascades; however, the regulatory properties and functional significance of such domains are not fully understood and often remain controversial issues. The present mini-review discusses our current knowledge of how the marriage between mitochondrial and cAMP compartmentalization is achieved and its effects on the biology of the cell. PMID:24646228

  9. The extracellular compartments of frog skeletal muscle.

    PubMed Central

    Neville, M C; Mathias, R T

    1979-01-01

    1. Detailed studies of solute efflux from frog sartorius muscle and single muscle fibres were carried out in order to characterize a 'special region' (Harris, 1963) in the extracellular space of muscle and determine whether this 'special region' is the sarcoplasmic reticulum. 2. The efflux of radioactive Na, Cl, glusose, 3-O-methylglucose, xylose, glycine, leucine, cycloleucine, Rb, K, inulin (mol. wt. 5000) and dextran (mol. wt. 17,000) from previously loaded muscles was studied. In all cases except dextran the curve had three components, a rapid (A) component which could be equated with efflux from the extracellular space proper, a slow (C) component representing cellular solute and an intermediate (B) component. The distribution space for the B component was 8% of muscle volume in summer frogs and 12% in winter frogs and appeared to be equal for all compounds studied. We tested the hypothesis that the B component originated from the sarcoplasmic reticulum. 3. The C component was missing from the dextran curves. Both dextran and inulin entered the compartment of origin of the B component (compartment B) to the same extent as small molecules. 4. For all compounds studies, the efflux rate constant for the A component could be predicted from the diffusion coefficient. For the B component the efflux rate constant was 6--10 times slower than that for the A component but was still proportional to the diffusion coefficient for the solute in question. 5. When Na and sucrose efflux from single fibres was followed, a B component was usually observed. The average distribution space for this component was small, averaging 1.5% of fibre volume. There was no difference between the average efflux rate constants for Na and sucrose. 6. In an appendix, the constraints placed on the properties of a hypothetical channel between the sarcoplasmic reticulum and the T-system by the linear electrical parameters of frog skeletal muscle are derived. It is shown that the conductance of such

  10. Myosin-Powered Membrane Compartment Drives Cytoplasmic Streaming, Cell Expansion and Plant Development.

    PubMed

    Peremyslov, Valera V; Cole, Rex A; Fowler, John E; Dolja, Valerian V

    2015-01-01

    Using genetic approaches, particle image velocimetry and an inert tracer of cytoplasmic streaming, we have made a mechanistic connection between the motor proteins (myosins XI), cargo transported by these motors (distinct endomembrane compartment defined by membrane-anchored MyoB receptors) and the process of cytoplasmic streaming in plant cells. It is shown that the MyoB compartment in Nicotiana benthamiana is highly dynamic moving with the mean velocity of ~3 μm/sec. In contrast, Golgi, mitochondria, peroxisomes, carrier vesicles and a cytosol flow tracer share distinct velocity profile with mean velocities of 0.6-1.5 μm/sec. Dominant negative inhibition of the myosins XI or MyoB receptors using overexpression of the N. benthamiana myosin cargo-binding domain or MyoB myosin-binding domain, respectively, resulted in velocity reduction for not only the MyoB compartment, but also each of the tested organelles, vesicles and cytoplasmic streaming. Furthermore, the extents of this reduction were similar for each of these compartments suggesting that MyoB compartment plays primary role in cytosol dynamics. Using gene knockout analysis in Arabidopsis thaliana, it is demonstrated that inactivation of MyoB1-4 results in reduced velocity of mitochondria implying slower cytoplasmic streaming. It is also shown that myosins XI and MyoB receptors genetically interact to contribute to cell expansion, plant growth, morphogenesis and proper onset of flowering. These results support a model according to which myosin-dependent, MyoB receptor-mediated transport of a specialized membrane compartment that is conserved in all land plants drives cytoplasmic streaming that carries organelles and vesicles and facilitates cell growth and plant development.

  11. Myosin-Powered Membrane Compartment Drives Cytoplasmic Streaming, Cell Expansion and Plant Development.

    PubMed

    Peremyslov, Valera V; Cole, Rex A; Fowler, John E; Dolja, Valerian V

    2015-01-01

    Using genetic approaches, particle image velocimetry and an inert tracer of cytoplasmic streaming, we have made a mechanistic connection between the motor proteins (myosins XI), cargo transported by these motors (distinct endomembrane compartment defined by membrane-anchored MyoB receptors) and the process of cytoplasmic streaming in plant cells. It is shown that the MyoB compartment in Nicotiana benthamiana is highly dynamic moving with the mean velocity of ~3 μm/sec. In contrast, Golgi, mitochondria, peroxisomes, carrier vesicles and a cytosol flow tracer share distinct velocity profile with mean velocities of 0.6-1.5 μm/sec. Dominant negative inhibition of the myosins XI or MyoB receptors using overexpression of the N. benthamiana myosin cargo-binding domain or MyoB myosin-binding domain, respectively, resulted in velocity reduction for not only the MyoB compartment, but also each of the tested organelles, vesicles and cytoplasmic streaming. Furthermore, the extents of this reduction were similar for each of these compartments suggesting that MyoB compartment plays primary role in cytosol dynamics. Using gene knockout analysis in Arabidopsis thaliana, it is demonstrated that inactivation of MyoB1-4 results in reduced velocity of mitochondria implying slower cytoplasmic streaming. It is also shown that myosins XI and MyoB receptors genetically interact to contribute to cell expansion, plant growth, morphogenesis and proper onset of flowering. These results support a model according to which myosin-dependent, MyoB receptor-mediated transport of a specialized membrane compartment that is conserved in all land plants drives cytoplasmic streaming that carries organelles and vesicles and facilitates cell growth and plant development. PMID:26426395

  12. Myosin-Powered Membrane Compartment Drives Cytoplasmic Streaming, Cell Expansion and Plant Development

    PubMed Central

    Peremyslov, Valera V.; Cole, Rex A.; Fowler, John E.; Dolja, Valerian V.

    2015-01-01

    Using genetic approaches, particle image velocimetry and an inert tracer of cytoplasmic streaming, we have made a mechanistic connection between the motor proteins (myosins XI), cargo transported by these motors (distinct endomembrane compartment defined by membrane-anchored MyoB receptors) and the process of cytoplasmic streaming in plant cells. It is shown that the MyoB compartment in Nicotiana benthamiana is highly dynamic moving with the mean velocity of ~3 μm/sec. In contrast, Golgi, mitochondria, peroxisomes, carrier vesicles and a cytosol flow tracer share distinct velocity profile with mean velocities of 0.6–1.5 μm/sec. Dominant negative inhibition of the myosins XI or MyoB receptors using overexpression of the N. benthamiana myosin cargo-binding domain or MyoB myosin-binding domain, respectively, resulted in velocity reduction for not only the MyoB compartment, but also each of the tested organelles, vesicles and cytoplasmic streaming. Furthermore, the extents of this reduction were similar for each of these compartments suggesting that MyoB compartment plays primary role in cytosol dynamics. Using gene knockout analysis in Arabidopsis thaliana, it is demonstrated that inactivation of MyoB1-4 results in reduced velocity of mitochondria implying slower cytoplasmic streaming. It is also shown that myosins XI and MyoB receptors genetically interact to contribute to cell expansion, plant growth, morphogenesis and proper onset of flowering. These results support a model according to which myosin-dependent, MyoB receptor-mediated transport of a specialized membrane compartment that is conserved in all land plants drives cytoplasmic streaming that carries organelles and vesicles and facilitates cell growth and plant development. PMID:26426395

  13. Vehicle hydraulic system that provides heat for passenger compartment

    DOEpatents

    Bartley, Bradley E.; Blass, James R.; Gibson, Dennis H.

    2001-01-01

    A vehicle includes a vehicle housing which defines a passenger compartment. Attached to the vehicle housing is a hydraulic system, that includes a hydraulic fluid which flows through at least one passageway within the hydraulic system. Also attached to the vehicle housing is a passenger compartment heating system. The passenger compartment heating system includes a heat exchanger, wherein a portion of the heat exchanger is a segment of the at least one passageway of the hydraulic system.

  14. Dynamic Compartments in the Imperative π-Calculus

    NASA Astrophysics Data System (ADS)

    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.

  15. Exertional compartment syndrome in covert mild hemophilia. A case report.

    PubMed

    Tountas, C P; Ferris, F O; Cobb, S W

    1992-07-01

    A 37-year-old white male experienced unexpected postoperative bleeding after fasciotomy and decompression for left pronator and compartment syndromes of the forearm. He was subsequently diagnosed with a mild form of hemophilia A. One year later, surgery was required for right pronator and compartment syndromes. Pre- and postoperative cryoprecipitate infusions controlled bleeding following the second operation until the patient discontinued his infusions, resulting in a wound hematoma. Covert mild hemophilia is implicated in the pathogenesis of his compartment syndromes.

  16. 7 CFR 58.510 - Rooms and compartments.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... compartments shall be ventilated to maintain sanitary conditions, preclude the growth of mold and air borne bacterial contaminants, prevent undue condensation of water vapor and minimize or eliminate...

  17. 7 CFR 58.510 - Rooms and compartments.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... compartments shall be ventilated to maintain sanitary conditions, preclude the growth of mold and air borne bacterial contaminants, prevent undue condensation of water vapor and minimize or eliminate...

  18. 7 CFR 58.510 - Rooms and compartments.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... compartments shall be ventilated to maintain sanitary conditions, preclude the growth of mold and air borne bacterial contaminants, prevent undue condensation of water vapor and minimize or eliminate...

  19. 7 CFR 58.510 - Rooms and compartments.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... compartments shall be ventilated to maintain sanitary conditions, preclude the growth of mold and air borne bacterial contaminants, prevent undue condensation of water vapor and minimize or eliminate...

  20. 7 CFR 58.510 - Rooms and compartments.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... compartments shall be ventilated to maintain sanitary conditions, preclude the growth of mold and air borne bacterial contaminants, prevent undue condensation of water vapor and minimize or eliminate...

  1. Coping with the diagnostic complexities of the compartment syndrome

    NASA Technical Reports Server (NTRS)

    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.

  2. Delayed onset thigh compartment syndrome secondary to contusion.

    PubMed

    Joglekar, Siddharth B; Rehman, Saqib

    2009-08-01

    While thigh compartment syndrome is relatively uncommon, it can occur in various situations. Multiple reports document thigh contusions as a cause of acute compartment syndrome; however, compartment syndrome of the thigh presenting primarily in a delayed fashion secondary to a contusion has not been described. This article reports a case of thigh compartment syndrome. A 39-year-old man sustained a left thigh contusion while playing basketball. He continued to play and also worked at the office over the next 2 days. Fifty-two hours postinjury, he developed severe pain in the thigh after a long walk. Increased swelling of the thigh followed, with numbness in the anterolateral thigh and pain with knee motion. He presented 60 hours postinjury with a compartment syndrome, and a lateral decompressive fasciotomy of the thigh was performed 62 hours postinjury. The wound was closed after 5 days. Three months postoperatively, the patient returned to playing basketball with no deficits. Treatment of established compartment syndrome in such cases is controversial, with some reports recommending nonoperative management. Contusion-related compartment syndromes are frequently associated with intramuscular bleeding in the involved compartment, which may accumulate slowly or worsen with further activity. Guidelines regarding return to sports need to be established in individuals sustaining severe contusions during sports-related activities to prevent compartment syndrome. Any individual sustaining such an injury should be under surveillance for delayed onset symptoms or signs of this potentially devastating syndrome.

  3. Acute exercise-induced bilateral thigh compartment syndrome.

    PubMed

    Boland, Michael R; Heck, Chris

    2009-03-01

    Acute compartment syndrome of the thigh is rare due to the space's ability to accommodate large volumes of fluid and, with the exception of the lateral septum, its thin compliant linings. This article describes a case of bilateral exercise-induced severe compartment syndrome treated with anterior and posterior fasciotomies. A 29-year-old man was admitted to intensive care with myoglobinuria. His left thigh was evaluated 18 hours later for compartment syndrome. The patient reported that 14 hours prior to initial presentation, he had participated in a 1-hour session of vigorous basketball. He gradually developed bilateral moderately severe thigh pain and tea-colored urine. Physical examination revealed pain secondary to passive stretch of both knees at 20 degrees flexion, plus firm anterior and posterior compartments to palpation. A handheld pressure monitor revealed the following compartment pressures: left anterior 80 mm Hg; left posterior 75 mm Hg; right anterior 45 mm Hg; and right posterior 50 mm Hg. Bilateral emergent anterior and posterior compartment fasciotomies were performed. The patient developed a significant severe distal motor and sensory neurological deficit on the left side, which recovered to 3/5 motor strength and protective sensation. At 6-month follow-up, he ambulated with the assistance of a left ankle foot orthosis. Acute severe compartment syndrome can occur following vigorous exercise. We recommend fasciotomies after exercise-induced acute compartment syndrome rather than initial observation because of the severity of morbidity associated with undertreated compartment syndrome.

  4. Processing and presentation of antigens derived from intracellular protozoan parasites

    PubMed Central

    Goldszmid, Romina S.; Sher, Alan

    2010-01-01

    Summary Control of parasitic protozoan infections requires the generation of efficient innate and adaptive immune responses, and in most cases both CD8 and CD4 T cells are necessary for host survival. Since intracellular protozoa remodel the vacuolar compartments in which they reside, it is not obvious how their antigens enter the MHC class I and class II pathways. Studies using genetically engineered parasites have shown that host cell targeting, intracellular compartmentalization, subcellular localization of antigen within the parasite and mechanism of invasion are important factors determining the presentation pathway utilized. The recent identification of endogenous parasite-derived CD8 T cell epitopes have helped confirm these concepts as well as provided new information on the processing pathways and the impact of parasite-stage specific antigen expression on the repertoire of responding T cells stimulated by infection. Elucidating the mechanisms governing antigen processing and presentation of intracellular protozoa may provide important insights needed for the rational design of effective vaccines. PMID:20153156

  5. Hypothesis: intracellular acidification contributes to infertility in varicocele.

    PubMed

    Ghabili, Kamyar; Shoja, Mohammadali M; Agutter, Paul S; Agarwal, Ashok

    2009-07-01

    We suggest that varicocele leads to male factor infertility by a mechanism involving underperfusion of the testis, a shortfall in glucose supply to the tissue, decreased flux through the pentose phosphate pathway, lowering of the reduced nicotinamide-adenine dinucleotide phosphate/oxidized nicotinamide-adenine dinucleotide phosphate ratio and the supply of glutathione to the antioxidant systems, increased levels of reactive oxygen species, peroxidation of spermatozoon membrane lipids, and the consequent generation of acidic degradation products and sequestering of spermine. Acidification of the seminal plasma impairs sperm motility and also inhibits most antioxidant enzymes, exacerbating the accumulation of reactive oxygen species and the resultant lowering of pH.

  6. Antigen capture and major histocompatibility class II compartments of freshly isolated and cultured human blood dendritic cells

    PubMed Central

    1995-01-01

    Dendritic cells (DC) represent potent antigen-presenting cells for the induction of T cell-dependent immune responses. Previous work on antigen uptake and presentation by human DC is based largely on studies of blood DC that have been cultured for various periods of time before analysis. These cultured cells may therefore have undergone a maturation process from precursors that have different capacities for antigen capture and presentation. We have now used immunoelectron microscopy and antigen presentation assays to compare freshly isolated DC (f-DC) and cultured DC (c-DC). f-DC display a round appearance, whereas c-DC display characteristic long processes. c-DC express much more cell surface major histocompatibility complex (MHC) class II than f-DC. The uptake of colloidal gold-labeled bovine serum albumin (BSA), however, is greater in f-DC, as is the presentation of 65-kD heat shock protein to T cell clones. The most striking discovery is that the majority of MHC class II molecules in both f-DC and c-DC occur in intracellular vacuoles with a complex shape (multivesicular and multilaminar). These MHC class II enriched compartments (MIIC) represent the site to which BSA is transported within 30 min. Although MIIC appear as more dense structures with less MHC class II molecules in f-DC than c-DC, the marker characteristics are very similar. The MIIC in both types of DC are acidic, contain invariant chain, and express the recently described HLA-DM molecule that can contribute to antigen presentation. CD19+ peripheral blood B cells have fewer MIIC and surface MHC class II expression than DCs, while monocytes had low levels of MIIC and surface MHC class II. These results demonstrate in dendritic cells the elaborate development of MIIC expressing several of the components that are required for efficient antigen presentation. PMID:7790816

  7. Pyroptotic cell death defends against intracellular pathogens

    PubMed Central

    Jorgensen, Ine; Miao, Edward A

    2015-01-01

    Summary Inflammatory caspases play a central role in innate immunity by responding to cytosolic signals and initiating a twofold response. First, caspase-1 induces the activation and secretion of the two prominent pro-inflammatory cytokines, interleukin-1β (IL-1β) and IL-18. Second, either caspase-1 or caspase-11 can trigger a form of lytic, programmed cell death called pyroptosis. Pyroptosis operates to remove the replication niche of intracellular pathogens, making them susceptible to phagocytosis and killing by a secondary phagocyte. However, aberrant, systemic activation of pyroptosis in vivo may contribute to sepsis. Emphasizing the efficiency of inflammasome detection of microbial infections, many pathogens have evolved to avoid or subvert pyroptosis. This review focuses on molecular and morphological characteristics of pyroptosis and the individual inflammasomes and their contribution to defense against infection in mice and humans. PMID:25879289

  8. Birbeck Granules Are Subdomains of Endosomal Recycling Compartment in Human Epidermal Langerhans Cells, Which Form Where Langerin Accumulates

    PubMed Central

    Mc Dermott, Ray; Ziylan, Umit; Spehner, Danièle; Bausinger, Huguette; Lipsker, Dan; Mommaas, Mieke; Cazenave, Jean-Pierre; Raposo, Graça; Goud, Bruno; de la Salle, Henri; Salamero, Jean; Hanau, Daniel

    2002-01-01

    Birbeck granules are unusual rod-shaped structures specific to epidermal Langerhans cells, whose origin and function remain undetermined. We investigated the intracellular location and fate of Langerin, a protein implicated in Birbeck granule biogenesis, in human epidermal Langerhans cells. In the steady state, Langerin is predominantly found in the endosomal recycling compartment and in Birbeck granules. Langerin internalizes by classical receptor-mediated endocytosis and the first Birbeck granules accessible to endocytosed Langerin are those connected to recycling endosomes in the pericentriolar area, where Langerin accumulates. Drug-induced inhibition of endocytosis results in the appearance of abundant open-ended Birbeck granule-like structures appended to the plasma membrane, whereas inhibition of recycling induces Birbeck granules to merge with a tubular endosomal network. In mature Langerhans cells, Langerin traffic is abolished and the loss of internal Langerin is associated with a concomitant depletion of Birbeck granules. Our results demonstrate an exchange of Langerin between early endosomal compartments and the plasma membrane, with dynamic retention in the endosomal recycling compartment. They show that Birbeck granules are not endocytotic structures, rather they are subdomains of the endosomal recycling compartment that form where Langerin accumulates. Finally, our results implicate ADP-ribosylation factor proteins in Langerin trafficking and the exchange between Birbeck granules and other endosomal membranes. PMID:11809842

  9. 9 CFR 354.241 - Cleaning of rooms and compartments.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... INSPECTION AND CERTIFICATION VOLUNTARY INSPECTION OF RABBITS AND EDIBLE PRODUCTS THEREOF Maintenance of... compartments. Rooms, compartments, or other parts of the official plant shall be kept clean and in sanitary... light fixtures in the official plant shall be kept clean. (c) All docks and rooms shall be kept...

  10. 14 CFR 23.1192 - Engine accessory compartment diaphragm.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Engine accessory compartment diaphragm. 23... Powerplant Powerplant Fire Protection § 23.1192 Engine accessory compartment diaphragm. For aircooled radial engines, the engine power section and all portions of the exhaust sytem must be isolated from the...

  11. 46 CFR 169.627 - Compartments containing diesel fuel tanks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Compartments containing diesel fuel tanks. 169.627 Section 169.627 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and Electrical Ventilation § 169.627 Compartments containing diesel fuel...

  12. 46 CFR 169.627 - Compartments containing diesel fuel tanks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Compartments containing diesel fuel tanks. 169.627 Section 169.627 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and Electrical Ventilation § 169.627 Compartments containing diesel fuel...

  13. 46 CFR 169.627 - Compartments containing diesel fuel tanks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Compartments containing diesel fuel tanks. 169.627 Section 169.627 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and Electrical Ventilation § 169.627 Compartments containing diesel fuel...

  14. 46 CFR 169.627 - Compartments containing diesel fuel tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Compartments containing diesel fuel tanks. 169.627 Section 169.627 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and Electrical Ventilation § 169.627 Compartments containing diesel fuel...

  15. 46 CFR 169.625 - Compartments containing diesel machinery.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Compartments containing diesel machinery. 169.625 Section 169.625 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and Electrical Ventilation § 169.625 Compartments containing diesel...

  16. 46 CFR 169.625 - Compartments containing diesel machinery.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Compartments containing diesel machinery. 169.625 Section 169.625 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and Electrical Ventilation § 169.625 Compartments containing diesel...

  17. 14 CFR 29.855 - Cargo and baggage compartments.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Cargo and baggage compartments. 29.855 Section 29.855 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Fire Protection § 29.855 Cargo and baggage compartments. (a)...

  18. 14 CFR 25.857 - Cargo compartment classification.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... control any fire that may start within the compartment. (d) (e) Class E. A Class E cargo compartment is... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Fire Protection § 25... which— (1) The presence of a fire would be easily discovered by a crewmember while at his station;...

  19. Compartment syndrome presenting as ischemia following extravasation of contrast material

    PubMed Central

    Grand, Aaron; Yeager, Brian; Wollstein, Ronit

    2008-01-01

    A case of acute compartment syndrome of the forearm, resulting from contrast dye extravasation that presented as upper extremity ischemia, is described. Timely surgical intervention resulted in an excellent outcome. When extravasation of dye occurs, the patient should be evaluated for compartment syndrome despite the possible lack of typical symptoms. PMID:19721799

  20. 14 CFR 25.857 - Cargo compartment classification.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Fire Protection § 25... (2) Each part of the compartment is easily accessible in flight. (b) Class B. A Class B cargo or baggage compartment is one in which— (1) There is sufficient access in flight to enable a crewmember...

  1. 14 CFR 25.857 - Cargo compartment classification.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Fire Protection § 25... (2) Each part of the compartment is easily accessible in flight. (b) Class B. A Class B cargo or baggage compartment is one in which— (1) There is sufficient access in flight to enable a crewmember...

  2. 49 CFR 179.220-9 - Compartment tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Compartment tanks. 179.220-9 Section 179.220-9... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SPECIFICATIONS FOR TANK CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.220-9 Compartment tanks....

  3. 49 CFR 179.200-9 - Compartment tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Compartment tanks. 179.200-9 Section 179.200-9... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SPECIFICATIONS FOR TANK CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.200-9 Compartment tanks....

  4. Spontaneous sequential compartment syndrome of the lower limbs.

    PubMed

    Abisi, Said; Yong, Yao Pey; Beech, Andrew; Oluwole, Akin; Tennant, William

    2013-10-01

    Spontaneous compartment syndrome is a rare condition and requires urgent surgical treatment to achieve favorable outcome. Several cases have been reported in the literature, and it has been associated with patients with diabetes. We present a case of acute spontaneous sequential compartment syndrome of the lower limbs in a patient with poorly controlled type 1 diabetes.

  5. Unrecognized acute exertional compartment syndrome of the leg and treatment.

    PubMed

    Popovic, Nebojsa; Bottoni, Craig; Cassidy, Charles

    2011-04-01

    Acute-on-chronic exertional compartment syndrome is rare and may be easily missed without a high degree of awareness and clinical suspicion. We report a case of unrecognized acute-on-chronic exertional compartment syndrome in a recreational soccer player. The late sequela of this condition, foot drop, was successfully treated with transfer of the peroneus longus tendon.

  6. Acute exertional compartment syndrome of the medial foot.

    PubMed

    Blacklidge, D K; Kurek, J B; Soto, A D; Kissel, C G

    1996-01-01

    A review of compartment syndrome, both acute and chronic, is presented. The pathophysiology, anatomy, diagnosis, and treatment are presented in relation to a unique case report. The case is one of acute exertional compartment syndrome of the medial foot treated by fasciotomy. This condition is uncommon in both its nature and location.

  7. Intracellular antioxidants: from chemical to biochemical mechanisms.

    PubMed

    Chaudière, J; Ferrari-Iliou, R

    1999-01-01

    Intracellular antioxidants include low molecular weight scavengers of oxidizing species, and enzymes which degrade superoxide and hydroperoxides. Such antioxidants systems prevent the uncontrolled formation of free radicals and activated oxygen species, or inhibit their reactions with biological structures. Hydrophilic scavengers are found in cytosolic, mitochondrial and nuclear compartments. Ascorbate and glutathione scavenge oxidizing free radicals in water by means of one-electron or hydrogen atom transfer. Similarly, ergothioneine scavenges hydroxyl radicals at very high rates, but it acts more specifically as a chemical scavenger of hypervalent ferryl complexes, halogenated oxidants and peroxynitrite-derived nitrating species, and as a physical quencher of singlet oxygen. Hydrophobic scavengers are found in cell membranes where they inhibit or interrupt chain reactions of lipid peroxidation. In animal cells, they include alpha-tocopherol (vitamin E) which is a primary scavenger of lipid peroxyl radicals, and carotenoids which are secondary scavengers of free radicals as well as physical quenchers of singlet oxygen. The main antioxidant enzymes include dismutases such as superoxide dismutases (SOD) and catalases, which do not consume cofactors, and peroxidases such as selenium-dependent glutathione peroxidases (GPx) in animals or ascorbate peroxidases (APx) in plants. The reducing coenzymes of peroxidases, and as a rule all reducing components of the antioxidant network, are regenerated at the expense of NAD(P)H produced in specific metabolic pathways. Synergistic and co-operative interactions of antioxidants rely on the sequential degradation of peroxides and free radicals as well as on mutual protections of enzymes. This antioxidant network can induce metabolic deviations and plays an important role in the regulation of protein expression and/or activity at the transcriptional or post-translational levels. Its biological significance is discussed in terms of

  8. A universal strategy for stable intracellular antibodies.

    PubMed

    Shaki-Loewenstein, Shelly; Zfania, Rahely; Hyland, Stephen; Wels, Winfried S; Benhar, Itai

    2005-08-01

    The expression of intracellular antibodies (intrabodies) in mammalian cells has provided a powerful tool to manipulate microbial and cellular signalling pathways in a highly precise manner. However, several technical hurdles have thus far restricted their more widespread use. In particular, single-chain antibodies (scFvs) have been reported to fold poorly in the reducing environment of the cytoplasm and as such there has been a reluctance to use scFv-phage libraries as a source of intrabodies unless a preselection step was applied to identify these rare scFvs that could fold properly in the absence of disulfide bonds. Recently, we reported that scFvs can be efficiently expressed within the cytoplasm of bacteria when fused at the C-terminus of the Escherichia coli maltose-binding protein (MBP). Here, we demonstrate that such MBP-scFvs are similarly stabilized when expressed in the mammalian cell cytoplasm as well as other compartments. This was demonstrated by comparing MBP-scFv fusions to the corresponding unfused scFvs that activate a defective beta-galactosidase enzyme, others that neutralize the wild-type beta-galactosidase enzyme, and an antibody that blocks the epidermal growth factor receptor. In all cases, the MBP-scFvs significantly outperformed their unfused counterparts. Our results suggest that fusion of scFvs to MBP, and possibly to other "chaperones in the context of a fusion protein", may provide a universal approach for efficient expression of intrabodies in the mammalian cell cytoplasm. This strategy should allow investigators to bypass much of the in vitro scFv characterization that is often not predictive of in vivo intrabody function and provide a more efficient use of large native and synthetic scFv-phage libraries already in existence to identify intrabodies that will be active in vivo.

  9. Superdiffusion dominates intracellular particle motion in the supercrowded cytoplasm of pathogenic Acanthamoeba castellanii

    NASA Astrophysics Data System (ADS)

    Reverey, Julia F.; Jeon, Jae-Hyung; Bao, Han; Leippe, Matthias; Metzler, Ralf; Selhuber-Unkel, Christine

    2015-06-01

    Acanthamoebae are free-living protists and human pathogens, whose cellular functions and pathogenicity strongly depend on the transport of intracellular vesicles and granules through the cytosol. Using high-speed live cell imaging in combination with single-particle tracking analysis, we show here that the motion of endogenous intracellular particles in the size range from a few hundred nanometers to several micrometers in Acanthamoeba castellanii is strongly superdiffusive and influenced by cell locomotion, cytoskeletal elements, and myosin II. We demonstrate that cell locomotion significantly contributes to intracellular particle motion, but is clearly not the only origin of superdiffusivity. By analyzing the contribution of microtubules, actin, and myosin II motors we show that myosin II is a major driving force of intracellular motion in A. castellanii. The cytoplasm of A. castellanii is supercrowded with intracellular vesicles and granules, such that significant intracellular motion can only be achieved by actively driven motion, while purely thermally driven diffusion is negligible.

  10. Superdiffusion dominates intracellular particle motion in the supercrowded cytoplasm of pathogenic Acanthamoeba castellanii.

    PubMed

    Reverey, Julia F; Jeon, Jae-Hyung; Bao, Han; Leippe, Matthias; Metzler, Ralf; Selhuber-Unkel, Christine

    2015-01-01

    Acanthamoebae are free-living protists and human pathogens, whose cellular functions and pathogenicity strongly depend on the transport of intracellular vesicles and granules through the cytosol. Using high-speed live cell imaging in combination with single-particle tracking analysis, we show here that the motion of endogenous intracellular particles in the size range from a few hundred nanometers to several micrometers in Acanthamoeba castellanii is strongly superdiffusive and influenced by cell locomotion, cytoskeletal elements, and myosin II. We demonstrate that cell locomotion significantly contributes to intracellular particle motion, but is clearly not the only origin of superdiffusivity. By analyzing the contribution of microtubules, actin, and myosin II motors we show that myosin II is a major driving force of intracellular motion in A. castellanii. The cytoplasm of A. castellanii is supercrowded with intracellular vesicles and granules, such that significant intracellular motion can only be achieved by actively driven motion, while purely thermally driven diffusion is negligible.

  11. Abdominal Compartment Syndrome Secondary to Chronic Constipation

    PubMed Central

    Flageole, Helene; Ouahed, Jodie; Walton, J. Mark; Yousef, Yasmin

    2011-01-01

    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. PMID:22606517

  12. Compartment in vertical flow reactor for ferruginous mine water

    NASA Astrophysics Data System (ADS)

    Hur, Won; Cheong, Young-Wook; Yim, Gil-Jae; Ji, Sang-Woo; Hong, Ji-Hye

    2014-05-01

    Mine effluents contain varying concentrations of ferrous ion along with other metal ions. Fe(II) that quickly oxidizes to form precipitates in the presence of oxygen under net alkaline or neutral conditions. Thus, passive treatment methods are designed for the mine water to reside in an open containment area so as to allow simultaneous oxidation and precipitation of Fe(II), such as in a lagoon or an oxidation pond. A vertical flow reactor (VFR) was also suggested to remediate ferruginous mine drainage passing down through an accreting bed of ochre. However, VFR has a limited operation time until the system begins to overflow. It was also demonstrated that two-compartment VFR has a longer operation time than single compartment VFR of same size. In this study, a mathematical model was developed as a part of efforts to explore the operation of VFR, showing dynamic changes in head differences, ochre depth and Fe(II)/Fe(III) concentration in the effluent flow. The analysis shows that Fe(II) oxidation and ochre formation should be balanced with permeability of ochre bed to maximize VFR operation time and minimize residual Fe(II) in the effluent. The model demonstrates that two compartment VFR can have a longer operation time than a single-compartment VFR and that an optimum compartment ratio exists that maximize VFR operation time. Accelerated Fe(II) oxidation significantly affects the optimum ratio of compartment area and reduced residual Fe(II) in the effluent. VFR operation time can be significantly prolonged by increasing the rate of ochre formation not by accelerated Fe(II) oxidation. Taken together, ochre forms largely in the first compartment while overflowed mine water with reduced iron contents is efficiently filtered in the second compartment. These results provide us a better understanding of VFR operation and optimum design criteria for maximum operation time in a two-compartment VFR. Rapid ochre accretion in the first compartment maintains constant hydraulic

  13. Bilaterally Symmetrical Lower Extremity Compartment Syndrome following Massive Transfusion.

    PubMed

    Karaoren, Gulsah; Bakan, Nurten; Tomruk, Senay Goksu; Topaç, Zelin; Kurtulmuş, Tuhan; Irkören, Saime

    2016-01-01

    Compartment syndrome is a serious condition characterized by raised intracompartmental pressure, which develops following trauma. Well leg compartment syndrome (WLCS) is a term reserved for compartment syndrome in a nontraumatic setting, usually resulting from prolonged lithotomy position during surgery. In literature, 8 cases have been reported regarding well leg compartment syndrome in a supine position and bilateral symmetrical involvement was observed in only 2 cases. In WLCS etiology, lengthy surgery, lengthy hypotension, and extremity malpositioning have been held responsible but one of the factors with a role in the etiology may have been the tissue oedema and impaired microcirculation formed from the effect of vasoactive mediators expressed into the circulation associated with the massive blood transfusion. The case is presented here regarding symmetrical lower extremity compartment syndrome after surgery in which massive transfusion was made for gross haemorrhage from an abdominal injury. In conclusion, blood transfusion applied at the required time is life-saving but potential risks must always be considered.

  14. Multiple compartment syndrome in a pediatric patient with CML.

    PubMed

    Lee, Dong-Ki; Jeong, Woong-Kyo; Lee, Dae-Hee; Lee, Soon-Hyuck

    2011-12-01

    Compartment syndrome is a limb-threatening and life-threatening emergency resulting from elevated intracompartmental pressure. Prompt surgical intervention and treatment are necessary to prevent irreparable damage to muscle and nerve tissues. Leukemic infiltration of the muscle is an unusual cause of compartment syndrome and has been documented to occur secondary to hyperleukocytic leukemias, most commonly in acute myeloid leukemia. We present a rare case of multiple compartment syndrome in the buttock and thigh of an 11-year-old male patient with chronic myelomonocytic leukemia. The diagnosis of acute compartment syndrome was delayed, causing irreversible tissue damage. Physicians are generally unfamiliar with leukemia-induced complications and may not initially suspect leukemic compartment syndrome because of its rarity. Awareness of its clinical features is critical, because early diagnosis and prompt surgical debridement can prevent significant morbidity and even death.

  15. Acute compartment syndrome in children: contemporary diagnosis, treatment, and outcome.

    PubMed

    Bae, D S; Kadiyala, R K; Waters, P M

    2001-01-01

    Compartment syndrome can be difficult to diagnose in a child, with delays in diagnosis leading to disastrous outcomes. Thirty-six cases of compartment syndrome in 33 pediatric patients were treated at the authors' institution from January 1, 1992, to December 31, 1997. There were 27 boys and 6 girls, with nearly equal upper and lower extremity involvement. Approximately 75% of these patients developed compartment syndrome in the setting of fracture. Pain, pallor, paresthesia, paralysis, and pulselessness were relatively unreliable signs and symptoms of compartment syndrome in these children. An increasing analgesia requirement in combination with other clinical signs, however, was a more sensitive indicator of compartment syndrome: all 10 patients with access to patient-controlled or nurse-administered analgesia during their initial evaluation demonstrated an increasing requirement for pain medication. With early diagnosis and expeditious treatment, >90% of the patients studied achieved full restoration of function.

  16. Senescence-inducible cell wall and intracellular purple acid phosphatases: implications for phosphorus remobilization in Hakea prostrata (Proteaceae) and Arabidopsis thaliana (Brassicaceae)

    PubMed Central

    Shane, Michael W.; Stigter, Kyla; Fedosejevs, Eric T.; Plaxton, William C.

    2014-01-01

    Despite its agronomic importance, the metabolic networks mediating phosphorus (P) remobilization during plant senescence are poorly understood. Highly efficient P remobilization (~85%) from senescing leaves and proteoid roots of harsh hakea (Hakea prostrata), a native ‘extremophile’ plant of south-western Australia, was linked with striking up-regulation of cell wall-localized and intracellular acid phosphatase (APase) and RNase activities. Non-denaturing PAGE followed by in-gel APase activity staining revealed senescence-inducible 120kDa and 60kDa intracellular APase isoforms, whereas only the 120kDa isoform was detected in corresponding cell wall fractions. Kinetic and immunological properties of the 120kDa and 60kDa APases partially purified from senescing leaves indicated that they are purple acid phosphatases (PAPs). Results obtained with cell wall-targeted hydrolases of harsh hakea were corroborated using Arabidopsis thaliana in which an ~200% increase in cell wall APase activity during leaf senescence was paralleled by accumulation of immunoreactive 55kDa AtPAP26 polypeptides. Senescing leaves of an atpap26 T-DNA insertion mutant displayed a >90% decrease in cell wall APase activity. Previous research established that senescing leaves of atpap26 plants exhibited a similar reduction in intracellular (vacuolar) APase activity, while displaying markedly impaired P remobilization efficiency and delayed senescence. It is hypothesized that up-regulation and dual targeting of PAPs and RNases to the cell wall and vacuolar compartments make a crucial contribution to highly efficient P remobilization that dominates the P metabolism of senescing tissues of harsh hakea and Arabidopsis. To the best of the authors’ knowledge, the apparent contribution of cell wall-targeted hydrolases to remobilizing key macronutrients such as P during senescence has not been previously suggested. PMID:25170100

  17. Where is it and How Does it Get There – Intracellular Localization and Traffic of P-glycoprotein

    PubMed Central

    Fu, Dong

    2013-01-01

    P-glycoprotein (P-gp), an ATP-binding cassette, is able to transport structurally and chemically unrelated substrates. Over-expression of P-gp in cancer cells significantly decreases the intercellular amount of anticancer drugs, and results in multidrug resistance in cancer cells, a major obstacle in cancer chemotherapy. P-gp is mainly localized on the plasma membrane and functions as a drug efflux pump; however, P-gp is also localized in many intracellular compartments, such as endoplasmic reticulum, Golgi, endosomes, and lysosomes. P-gp moves between the intracellular compartments and the plasma membrane in a microtubule-actin dependent manner. This review highlights our current understanding of (1) the intracellular localization of P-gp; (2) the traffic and cycling pathways among the cellular compartments as well as between these compartments and the plasma membrane; and (3) the cellular factors regulating P-gp traffic and cycling. This review also presents a potential implication in overcoming P-gp-mediated multidrug resistance by targeting P-gp traffic and cycling pathways and impairing P-gp localization on the plasma membrane. PMID:24416721

  18. Sirtuin inhibitor sirtinol is an intracellular iron chelator

    PubMed Central

    Gautam, R.; Akam, E. A.; Astashkin, A. V.; Loughrey, J. J.

    2015-01-01

    Sirtinol is a known inhibitor of sirtuin proteins, a family of deacetylases involved in the pathophysiology of aging. Spectroscopic and structural data reveal that this compound is also an iron chelator forming high-spin ferric species in vitro and in cultured leukemia cells. Interactions with the highly regulated iron pool therefore contribute to its overall intracellular agenda. PMID:25715179

  19. Intracellular fate of Mycobacterium avium: use of dual-label spectrofluorometry to investigate the influence of bacterial viability and opsonization on phagosomal pH and phagosome-lysosome interaction.

    PubMed Central

    Oh, Y K; Straubinger, R M

    1996-01-01

    Mycobacterium avium is a facultative intracellular pathogen that can survive and replicate within macrophages. We tested the hypotheses that survival mechanisms may include alteration of phagosomal pH or inhibition of phagosome-lysosome fusion. M. avium was surface labeled with N-hydroxysuccinimidyl esters of carboxyfluorescein (CF) and rhodamine (Rho) to enable measurement of the pH of individual M. avium-containing phagosomes and the interactions of bacterium-containing phagosomes with labeled secondary lysosomes. CF fluorescence is pH sensitive, whereas Rho is pH insensitive; pH can be calculated from their fluorescence ratios. Surface labeling of M. avium did not affect viability in broth cultures or within J774, a murine macrophage-like cell line. By fluorescence spectroscopy, live M. avium was exposed to an environmental pH of approximately 5.7 at 6 h after phagocytosis, whereas similarly labeled Salmonella typhimurium, zymosan A, or heat-killed M. avium encountered an environmental pH of < 5.0. Video fluorescence and laser scanning confocal microscopy gave consistent pH results and demonstrated the heterogeneity of intracellular fate early in infection. pH became more homogeneous 6 h after infection. M. avium cells were coated with immunoglobulin G (IgG) or opsonized to investigate whether phagocytosis by the corresponding receptors would alter intracellular fate. Opsonized, unopsonized, and IgG-coated M. avium cells entered compartments of similar pH. Finally, the spatial distribution of intracellular bacteria and secondary lysosomes was compared. Only 18% of live fluorescent M. avium cells colocalized with fluorescent lysosomes, while 98% of heat-killed bacteria colocalized. Thus, both inhibition of phagosome-lysosome fusion and alteration of phagosomal pH may contribute to the intracellular survival of M. avium. PMID:8557358

  20. Medial Compartment Decompression by Fibular Osteotomy to Treat Medial Compartment Knee Osteoarthritis: A Pilot Study.

    PubMed

    Yang, Zong-You; Chen, Wei; Li, Cun-Xiang; Wang, Juan; Shao, De-Cheng; Hou, Zhi-Yong; Gao, Shi-Jun; Wang, Fei; Li, Ji-Dong; Hao, Jian-Dong; Chen, Bai-Cheng; Zhang, Ying-Ze

    2015-12-01

    Compared with high tibial osteotomy and total knee arthroplasty, the authors found a simpler surgical procedure, partial fibular osteotomy, could effectively relieve knee pain and also correct the varus deformity for patients with medial compartment knee osteoarthritis (OA). From January 1996 to April 2012, a total of 156 patients with medial compartment OA were treated by proximal fibular osteotomy in the authors' hospital. A 2-cm-long section of fibula was resected 6 to 10 cm below the fibular head. A total of 110 patients with follow-up of more than 2 years were included in the study, including 34 males and 76 females with an average age of 59.2 years. Anteroposterior and lateral weight-bearing radiographs, the femorotibial angle (FTA) and lateral joint space, and the American Knee Society Score (KSS) and the visual analog scale (VAS) score of the knee joint were evaluated preoperatively and at final follow-up, respectively. At final follow-up, mean FTA and lateral joint space were 179.4°±1.8° and 6.9±0.7 mm, respectively, which were significantly smaller than those measured preoperatively (182.7°±2.0° and 12.2±1.1 mm, respectively; both P<.001). Mean KSS at final follow-up was 92.3±31.7, significantly higher than the mean preoperative score of 45.0±21.3 (P<.001). Mean VAS score and interquartile range were 2.0 and 2.0, significantly lower than the preoperative data (7 and 1.0, respectively; P<.001). The authors found that proximal fibular osteotomy can significantly improve both the radiographic appearance and function of the affected knee joint and also achieve long-term pain relief. This procedure may be an alternative treatment option for medial compartment OA.

  1. Medial Compartment Decompression by Fibular Osteotomy to Treat Medial Compartment Knee Osteoarthritis: A Pilot Study.

    PubMed

    Yang, Zong-You; Chen, Wei; Li, Cun-Xiang; Wang, Juan; Shao, De-Cheng; Hou, Zhi-Yong; Gao, Shi-Jun; Wang, Fei; Li, Ji-Dong; Hao, Jian-Dong; Chen, Bai-Cheng; Zhang, Ying-Ze

    2015-12-01

    Compared with high tibial osteotomy and total knee arthroplasty, the authors found a simpler surgical procedure, partial fibular osteotomy, could effectively relieve knee pain and also correct the varus deformity for patients with medial compartment knee osteoarthritis (OA). From January 1996 to April 2012, a total of 156 patients with medial compartment OA were treated by proximal fibular osteotomy in the authors' hospital. A 2-cm-long section of fibula was resected 6 to 10 cm below the fibular head. A total of 110 patients with follow-up of more than 2 years were included in the study, including 34 males and 76 females with an average age of 59.2 years. Anteroposterior and lateral weight-bearing radiographs, the femorotibial angle (FTA) and lateral joint space, and the American Knee Society Score (KSS) and the visual analog scale (VAS) score of the knee joint were evaluated preoperatively and at final follow-up, respectively. At final follow-up, mean FTA and lateral joint space were 179.4°±1.8° and 6.9±0.7 mm, respectively, which were significantly smaller than those measured preoperatively (182.7°±2.0° and 12.2±1.1 mm, respectively; both P<.001). Mean KSS at final follow-up was 92.3±31.7, significantly higher than the mean preoperative score of 45.0±21.3 (P<.001). Mean VAS score and interquartile range were 2.0 and 2.0, significantly lower than the preoperative data (7 and 1.0, respectively; P<.001). The authors found that proximal fibular osteotomy can significantly improve both the radiographic appearance and function of the affected knee joint and also achieve long-term pain relief. This procedure may be an alternative treatment option for medial compartment OA. PMID:26652332

  2. Transferrin receptor containing the SDYQRL motif of TGN38 causes a reorganization of the recycling compartment but is not targeted to the TGN.

    PubMed

    Johnson, A O; Ghosh, R N; Dunn, K W; Garippa, R; Park, J; Mayor, S; Maxfield, F R; McGraw, T E

    1996-12-01

    The SDYQRL motif of the cytoplasmic domain of TGN38 is involved in targeting TGN38 from endosomes to the TGN. To create a system for studying this pathway, we replaced the native transferrin receptor (TR) internalization motif (YTRF) with the SDYQRL TGN-targeting motif. The advantages of using TR as a reporter molecule include the ability to monitor trafficking, in both biochemical and microscopy experiments, using the natural ligand transferrin. When expressed in CHO cells, the SDYQRL-TR construct accumulated in juxtanuclear tubules and vesicles that are in the vicinity of the TGN. The SDYQRL-TR-containing structures, however, do not colocalize with TGN markers (e.g., NBD ceramide), and therefore the SDYQRL motif is not sufficient to target the TR to the TGN. The morphology of the SDYQRL-TR-containing juxtanuclear structures is different from the recycling compartment found in cells expressing the wild-type TR. In addition, the SDYQRL-TR-containing juxtanuclear compartment is more acidic than the recycling compartment in cells expressing the wild-type TR. The juxtanuclear compartment, however, is a bona fide recycling compartment since SDYQRL-TR was recycled back to the cell surface at a rate comparable to the wild-type TR, and sphingomyelin and cellubrevin, both of which label all compartments of the endocytic recycling pathway, colocalize with SDYQRL-TR in the juxtanuclear structures. These findings demonstrate that expression of the SDYQRL-TR construct alters the morphology and pH of endocytic recycling compartments rather than selectively affecting the intracellular trafficking pathway of the SDYQRL-TR construct. Therefore, the SDYQRL trafficking motif is not simply a molecular address that targets proteins to the TGN, but it can play an active role in determining the physical characteristics of endosomal compartments.

  3. Phosphorylation-mediated RNA/peptide complex coacervation as a model for intracellular liquid organelles

    NASA Astrophysics Data System (ADS)

    Aumiller, William M.; Keating, Christine D.

    2016-02-01

    Biological cells are highly organized, with numerous subcellular compartments. Phosphorylation has been hypothesized as a means to control the assembly/disassembly of liquid-like RNA- and protein-rich intracellular bodies, or liquid organelles, that lack delimiting membranes. Here, we demonstrate that charge-mediated phase separation, or complex coacervation, of RNAs with cationic peptides can generate simple model liquid organelles capable of reversibly compartmentalizing biomolecules. Formation and dissolution of these liquid bodies was controlled by changes in peptide phosphorylation state using a kinase/phosphatase enzyme pair. The droplet-generating phase transition responded to modification of even a single serine residue. Electrostatic interactions between the short cationic peptides and the much longer polyanionic RNAs drove phase separation. Coacervates were also formed on silica beads, a primitive model for localization at specific intracellular sites. This work supports phosphoregulation of complex coacervation as a viable mechanism for dynamic intracellular compartmentalization in membraneless organelles.

  4. Single cell measurements of vacuolar rupture caused by intracellular pathogens.

    PubMed

    Keller, Charlotte; Mellouk, Nora; Danckaert, Anne; Simeone, Roxane; Brosch, Roland; Enninga, Jost; Bobard, Alexandre

    2013-06-12

    Shigella flexneri are pathogenic bacteria that invade host cells entering into an endocytic vacuole. Subsequently, the rupture of this membrane-enclosed compartment allows bacteria to move within the cytosol, proliferate and further invade neighboring cells. Mycobacterium tuberculosis is phagocytosed by immune cells, and has recently been shown to rupture phagosomal membrane in macrophages. We developed a robust assay for tracking phagosomal membrane disruption after host cell entry of Shigella flexneri or Mycobacterium tuberculosis. The approach makes use of CCF4, a FRET reporter sensitive to β-lactamase that equilibrates in the cytosol of host cells. Upon invasion of host cells by bacterial pathogens, the probe remains intact as long as the bacteria reside in membrane-enclosed compartments. After disruption of the vacuole, β-lactamase activity on the surface of the intracellular pathogen cleaves CCF4 instantly leading to a loss of FRET signal and switching its emission spectrum. This robust ratiometric assay yields accurate information about the timing of vacuolar rupture induced by the invading bacteria, and it can be coupled to automated microscopy and image processing by specialized algorithms for the detection of the emission signals of the FRET donor and acceptor. Further, it allows investigating the dynamics of vacuolar disruption elicited by intracellular bacteria in real time in single cells. Finally, it is perfectly suited for high-throughput analysis with a spatio-temporal resolution exceeding previous methods. Here, we provide the experimental details of exemplary protocols for the CCF4 vacuolar rupture assay on HeLa cells and THP-1 macrophages for time-lapse experiments or end points experiments using Shigella flexneri as well as multiple mycobacterial strains such as Mycobacterium marinum, Mycobacterium bovis, and Mycobacterium tuberculosis.

  5. Insight into nanoparticle cellular uptake and intracellular targeting

    PubMed Central

    Yameen, Basit; Choi, Won Il; Vilos, Cristian; Swami, Archana; Shi, Jinjun; Farokhzad, Omid C.

    2014-01-01

    Collaborative efforts from the fields of biology, materials science, and engineering are leading to exciting progress in the development of nanomedicines. Since the targets of many therapeutic agents are localized in subcellular compartments, modulation of nanoparticle-cell interactions for an efficient cellular uptake through the plasma membrane, and the development of nanomedicines for precise delivery to subcellular compartments remain formidable challenges. The cellular internalization routes have a determining effect on the post-internalization fate and intracellular localization of nanoparticles. This review highlights the cellular uptake routes most relevant to the field of non-targeted nanomedicine, and presents an account of ligand targeted nanoparticles for receptor mediated cellular internalization as a strategy for modulating the cellular uptake of nanoparticles. Ligand targeted nanoparticles have been the main impetus behind the progress of nanomedicines towards the clinic. This strategy has even resulted in a remarkable development towards effective oral delivery of nanomedicines that can overcome the intestinal epithelial cellular barrier. A detailed overview of the recent developments towards subcellular targeting that is emerging as a platform for the next generation organelle specific nanomedicines is also provided. Each section of the review includes prospect, potential, and concrete expectations from the field of targeted nanomedicines and strategies to meet those expectations. PMID:24984011

  6. Insight into nanoparticle cellular uptake and intracellular targeting.

    PubMed

    Yameen, Basit; Choi, Won Il; Vilos, Cristian; Swami, Archana; Shi, Jinjun; Farokhzad, Omid C

    2014-09-28

    Collaborative efforts from the fields of biology, materials science, and engineering are leading to exciting progress in the development of nanomedicines. Since the targets of many therapeutic agents are localized in subcellular compartments, modulation of nanoparticle-cell interactions for efficient cellular uptake through the plasma membrane and the development of nanomedicines for precise delivery to subcellular compartments remain formidable challenges. Cellular internalization routes determine the post-internalization fate and intracellular localization of nanoparticles. This review highlights the cellular uptake routes most relevant to the field of non-targeted nanomedicine and presents an account of ligand-targeted nanoparticles for receptor-mediated cellular internalization as a strategy for modulating the cellular uptake of nanoparticles. Ligand-targeted nanoparticles have been the main impetus behind the progress of nanomedicines towards the clinic. This strategy has already resulted in remarkable progress towards effective oral delivery of nanomedicines that can overcome the intestinal epithelial barrier. A detailed overview of the recent developments in subcellular targeting as a novel platform for next-generation organelle-specific nanomedicines is also provided. Each section of the review includes prospects, potential, and concrete expectations from the field of targeted nanomedicines and strategies to meet those expectations.

  7. Intracellular processing of the Newcastle disease virus fusion glycoprotein

    SciTech Connect

    Morrison, T.; Ward, L.J.; Semerjian, A.

    1985-03-01

    The fusion glycoprotein (Fo) of Newcastle disease virus is cleaved at an intracellular site into F1 and F2. This result was confirmed by comparing the transit time of the fusion protein to the cell surface with the time course of cleavage of Fo. The time required for cleavage of half of the pulse-labeled Fo protein is ca. 40 min faster than the half time of the transit of the fusion protein to the cell surface. To determine the cell compartment in which cleavage occurs, use was made of inhibitors which block glycoprotein migration at specific points and posttranslational modifications known to occur in specific cell membranes. Cleavage of Fo is inhibited by carbonyl cyanide m-chlorophenylhydrazone; thus, cleavage does not occur in the rough endoplasmic reticulum. Monensin blocks the incorporation of Newcastle disease virus glycoproteins into virions and blocks the cleavage of the fusion glycoprotein. However, Fo cannot be radioactively labeled with (/sup 3/H) fucose, whereas F1 is readily labeled. These results argue that cleavage occurs in the trans Golgi membranes or in a cell compartment occupied by glycoproteins quite soon after their transit through the trans Golgi membranes. The implications of the results presented for the transit times of the fusion protein between subcellular organelles are discussed.

  8. Steroid signaling activation and intracellular localization of sex steroid receptors.

    PubMed

    Giraldi, Tiziana; Giovannelli, Pia; Di Donato, Marzia; Castoria, Gabriella; Migliaccio, Antimo; Auricchio, Ferdinando

    2010-12-01

    In addition to stimulating gene transcription, sex steroids trigger rapid, non-genomic responses in the extra-nuclear compartment of target cells. These events take place within seconds or minutes after hormone administration and do not require transcriptional activity of sex steroid receptors. Depending on cell systems, activation of extra-nuclear signaling pathways by sex steroids fosters cell cycle progression, prevents apoptosis, leads to epigenetic modifications and increases cell migration through cytoskeleton changes. These findings have raised the question of intracellular localization of sex steroid receptors mediating these responses. During the past years, increasing evidence has shown that classical sex steroid receptors localized in the extra-nuclear compartment or close to membranes of target cells induce these events. The emerging picture is that a process of bidirectional control between signaling activation and sex steroid receptor localization regulates the outcome of hormonal responses in target cells. This mechanism ensures cell cycle progression in estradiol-treated breast cancer cells, and its derangement might occur in progression of human proliferative diseases. These findings will be reviewed here together with unexpected examples of the relationship between sex steroid receptor localization, signaling activation and biological responses in target cells. We apologize to scientists whose reports are not mentioned or extensively discussed owing to space limitations.

  9. Multiple ecto-nucleoside triphosphate diphosphohydrolases facilitate intracellular replication of Legionella pneumophila.

    PubMed

    Riedmaier, Patrice; Sansom, Fiona M; Sofian, Trifina; Beddoe, Travis; Schuelein, Ralf; Newton, Hayley J; Hartland, Elizabeth L

    2014-09-01

    Legionella pneumophila is an opportunistic pathogen that replicates within alveolar macrophages resulting in the onset of severe atypical pneumonia. Previously we have identified Lpg1905, a eukaryotic-type ecto-NTPDase (nucleoside triphosphate diphosphohydrolase) from L. pneumophila that was required for optimal intracellular replication and virulence in a mouse lung infection model. In the present study, we characterized the activity of a second eukaryotic-type NTPDase, Lpg0971, from L. pneumophila. We observed that recombinant Lpg0971 hydrolysed only ATP and exhibited divalent cation preference for manganese (II) ions. Similar to lpg1905, an lpg0971 mutant carrying the plasmid pMIP was attenuated in a mouse lung infection model and impaired for replication in human macrophages and amoebae. Increased trafficking of the LCV (Legionella-containing vacuole) to a LAMP-1 (lysosome-associated membrane protein-1)-positive compartment was observed for both the lpg1905 and lpg0971 mutants carrying pMIP. Complementation with either lpg1905 or lpg0971 restored intracellular replication, suggesting that a minimum level of ATPase activity was required for this function. A double lpg1905/0971 mutant was not more impaired for intracellular replication than the single mutants and complementation of the double mutant with lpg0971, but not lpg1905, restored intracellular replication. This suggested that although the NTPDases have overlapping activities they have distinct functions. Unlike many eukaryotic-type proteins from L. pneumophila, neither Lpg1905 nor Lpg0971 were translocated into the host cell by the Dot/Icm (defective in organelle trafficking/intracellular multiplication) type IV secretion system. Overall our data suggest that the ability of L. pneumophila to replicate in eukaryotic cells relies in part on the ability of the pathogen to hydrolyse ATP within an intracellular compartment.

  10. Stochastic Turing patterns: analysis of compartment-based approaches.

    PubMed

    Cao, Yang; Erban, Radek

    2014-12-01

    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.

  11. The Interaction between the Fiber Knob Domain and the Cellular Attachment Receptor Determines the Intracellular Trafficking Route of Adenoviruses

    PubMed Central

    Shayakhmetov, Dmitry M.; Li, Zong-Yi; Ternovoi, Vladimir; Gaggar, Anuj; Gharwan, Helen; Lieber, André

    2003-01-01

    Most of the presently used adenovirus (Ad) vectors are based on serotype 5. However, the application of these vectors is limited by the native tropism of Ad5. To address this problem, a series of fiber chimeric vectors were produced to take advantage of the different cellular receptors used by Ad of different subgroups. In this study we utilize an Ad5-based chimeric vector containing sequences encoding the Ad35 fiber knob domain instead of the Ad5 knob (Ad5/35L) to analyze factors responsible for selection of intracellular trafficking routes by Ads. By competition analysis with recombinant Ad5 and Ad35 knobs we showed that the Ad5/35L vector infected cells through a receptor different from the Ad5 receptor. Intracellular trafficking of Ad5 and Ad5/35L viruses was analyzed in HeLa cells by tracking fluorophore-conjugated Ad particles, by immunostaining for capsid hexon protein, by electron microscopy, and by Southern blotting for viral DNA. These studies showed that the interaction with the Ad35 receptor(s) predestines Ad5/35L vector to intracellular trafficking pathways different from those of Ad5. Ad5 efficiently escaped from the endosomes early after infection. In contrast, Ad5/35L remained longer in late endosomal/lysosomal compartments and used them to achieve localization to the nucleus. However, a significant portion of Ad5/35L particles appeared to be recycled back to the cell surface. This phenomenon resulted in significantly less efficient Ad5/35L-mediated gene transfer compared to that of Ad5. We also demonstrated that the selection of intracellular trafficking routes was determined by the fiber knob domain and did not depend on the length of the fiber shaft. This study contributes to a better understanding of the mechanisms that govern the infection of retargeted, capsid-modified vectors which have potential application for hematopoietic stem cell and tumor gene therapy. PMID:12610146

  12. Organic Pollutant Penetration through Fruit Polyester Skin: A Modified Three-compartment Diffusion Model

    NASA Astrophysics Data System (ADS)

    Li, Yungui; Li, Qingqing; Chen, Baoliang

    2016-03-01

    The surface of plants is covered by a continuous but heterogeneous cuticular membrane (CM). Serving as the first protective barrier, the uptake and transport behavior of organic pollutants at this interface continue to engage the research efforts of environmental chemist. To date, the contributions of cuticular components as a defense against the organic pollutants penetration remain unresolved. In this study, the unsteady-state penetration characteristics of phenanthrene (PHE) through isolated fruit CM was investigated. PHE penetration was differentiated by three cuticular compartments: epicuticular waxes (EW), cuticle proper (CP) and cuticular layer (CL). The driving force for PHE penetration was ascribed to the sharp concentration gradient built up endogenously by cuticular compartments with different lipophilic affinities. A modified penetration model was established and verified in terms of its general suitability for the hydrophobic chemicals and CMs of various plant species (apple, tomato and potato). The new three-compartment model demonstrates much higher accuracy in characterizing the uptake and transport behavior of semivolatile chemicals with fewer limitations in terms of environmental conditions and complexity (e.g., coexisting contaminants and temperature). This model could contribute to a more comprehensive understanding on the role of polymeric lipids in the organic pollutant sorption and transport into plants.

  13. Organic Pollutant Penetration through Fruit Polyester Skin: A Modified Three-compartment Diffusion Model.

    PubMed

    Li, Yungui; Li, Qingqing; Chen, Baoliang

    2016-01-01

    The surface of plants is covered by a continuous but heterogeneous cuticular membrane (CM). Serving as the first protective barrier, the uptake and transport behavior of organic pollutants at this interface continue to engage the research efforts of environmental chemist. To date, the contributions of cuticular components as a defense against the organic pollutants penetration remain unresolved. In this study, the unsteady-state penetration characteristics of phenanthrene (PHE) through isolated fruit CM was investigated. PHE penetration was differentiated by three cuticular compartments: epicuticular waxes (EW), cuticle proper (CP) and cuticular layer (CL). The driving force for PHE penetration was ascribed to the sharp concentration gradient built up endogenously by cuticular compartments with different lipophilic affinities. A modified penetration model was established and verified in terms of its general suitability for the hydrophobic chemicals and CMs of various plant species (apple, tomato and potato). The new three-compartment model demonstrates much higher accuracy in characterizing the uptake and transport behavior of semivolatile chemicals with fewer limitations in terms of environmental conditions and complexity (e.g., coexisting contaminants and temperature). This model could contribute to a more comprehensive understanding on the role of polymeric lipids in the organic pollutant sorption and transport into plants. PMID:27009902

  14. Organic Pollutant Penetration through Fruit Polyester Skin: A Modified Three-compartment Diffusion Model

    PubMed Central

    Li, Yungui; Li, Qingqing; Chen, Baoliang

    2016-01-01

    The surface of plants is covered by a continuous but heterogeneous cuticular membrane (CM). Serving as the first protective barrier, the uptake and transport behavior of organic pollutants at this interface continue to engage the research efforts of environmental chemist. To date, the contributions of cuticular components as a defense against the organic pollutants penetration remain unresolved. In this study, the unsteady-state penetration characteristics of phenanthrene (PHE) through isolated fruit CM was investigated. PHE penetration was differentiated by three cuticular compartments: epicuticular waxes (EW), cuticle proper (CP) and cuticular layer (CL). The driving force for PHE penetration was ascribed to the sharp concentration gradient built up endogenously by cuticular compartments with different lipophilic affinities. A modified penetration model was established and verified in terms of its general suitability for the hydrophobic chemicals and CMs of various plant species (apple, tomato and potato). The new three-compartment model demonstrates much higher accuracy in characterizing the uptake and transport behavior of semivolatile chemicals with fewer limitations in terms of environmental conditions and complexity (e.g., coexisting contaminants and temperature). This model could contribute to a more comprehensive understanding on the role of polymeric lipids in the organic pollutant sorption and transport into plants. PMID:27009902

  15. Quantification and characterization of mucosa-associated and intracellular Escherichia coli in inflamatory bowel disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background and aims: Mucosa-associated E. coli are abundant in Crohn’s disease (CD) but whether these bacteria gain intracellular access within the mucosa is less certain. If E. coli does gain intracellular access in CD, the contribution of bacterial pathogenicity as opposed to a defect in host inna...

  16. Compartment-dependent mitochondrial alterations in experimental ALS, the effects of mitophagy and mitochondriogenesis.

    PubMed

    Natale, Gianfranco; Lenzi, Paola; Lazzeri, Gloria; Falleni, Alessandra; Biagioni, Francesca; Ryskalin, Larisa; Fornai, Francesco

    2015-01-01

    Amyotrophic lateral sclerosis (ALS) is characterized by massive loss of motor neurons. Data from ALS patients and experimental models indicate that mitochondria are severely damaged within dying or spared motor neurons. Nonetheless, recent data indicate that mitochondrial preservation, although preventing motor neuron loss, fails to prolong lifespan. On the other hand, the damage to motor axons plays a pivotal role in determining both lethality and disease course. Thus, in the present article each motor neuron compartment (cell body, central, and peripheral axons) of G93A SOD-1 mice was studied concerning mitochondrial alterations as well as other intracellular structures. We could confirm the occurrence of ALS-related mitochondrial damage encompassing total swelling, matrix dilution and cristae derangement along with non-pathological variations of mitochondrial size and number. However, these alterations occur to a different extent depending on motor neuron compartment. Lithium, a well-known autophagy inducer, prevents most pathological changes. However, the efficacy of lithium varies depending on which motor neuron compartment is considered. Remarkably, some effects of lithium are also evident in wild type mice. Lithium is effective also in vitro, both in cell lines and primary cell cultures from the ventral spinal cord. In these latter cells autophagy inhibition within motor neurons in vitro reproduced ALS pathology which was reversed by lithium. Muscle and glial cells were analyzed as well. Cell pathology was mostly severe within peripheral axons and muscles of ALS mice. Remarkably, when analyzing motor axons of ALS mice a subtotal clogging of axoplasm was described for the first time, which was modified under the effects of lithium. The effects induced by lithium depend on several mechanisms such as direct mitochondrial protection, induction of mitophagy and mitochondriogenesis. In this study, mitochondriogenesis induced by lithium was confirmed in situ by a

  17. Compartment-dependent mitochondrial alterations in experimental ALS, the effects of mitophagy and mitochondriogenesis

    PubMed Central

    Natale, Gianfranco; Lenzi, Paola; Lazzeri, Gloria; Falleni, Alessandra; Biagioni, Francesca; Ryskalin, Larisa; Fornai, Francesco

    2015-01-01

    Amyotrophic lateral sclerosis (ALS) is characterized by massive loss of motor neurons. Data from ALS patients and experimental models indicate that mitochondria are severely damaged within dying or spared motor neurons. Nonetheless, recent data indicate that mitochondrial preservation, although preventing motor neuron loss, fails to prolong lifespan. On the other hand, the damage to motor axons plays a pivotal role in determining both lethality and disease course. Thus, in the present article each motor neuron compartment (cell body, central, and peripheral axons) of G93A SOD-1 mice was studied concerning mitochondrial alterations as well as other intracellular structures. We could confirm the occurrence of ALS-related mitochondrial damage encompassing total swelling, matrix dilution and cristae derangement along with non-pathological variations of mitochondrial size and number. However, these alterations occur to a different extent depending on motor neuron compartment. Lithium, a well-known autophagy inducer, prevents most pathological changes. However, the efficacy of lithium varies depending on which motor neuron compartment is considered. Remarkably, some effects of lithium are also evident in wild type mice. Lithium is effective also in vitro, both in cell lines and primary cell cultures from the ventral spinal cord. In these latter cells autophagy inhibition within motor neurons in vitro reproduced ALS pathology which was reversed by lithium. Muscle and glial cells were analyzed as well. Cell pathology was mostly severe within peripheral axons and muscles of ALS mice. Remarkably, when analyzing motor axons of ALS mice a subtotal clogging of axoplasm was described for the first time, which was modified under the effects of lithium. The effects induced by lithium depend on several mechanisms such as direct mitochondrial protection, induction of mitophagy and mitochondriogenesis. In this study, mitochondriogenesis induced by lithium was confirmed in situ by a

  18. Lateral compartment cartilage changes and lateral elbow pain.

    PubMed

    Rajeev, Aysha; Pooley, Joseph

    2009-02-01

    The aim of our study is to document the arthroscopic findings in resistant lateral elbow pain. We have reviewed the findings in a consecutive series of 117 elbow arthroscopies performed on patients with lateral elbow pain resistant to conservative treatment. We found established degenerative changes involving articular cartilage in 68 patients (59%). In 60 of these 68 patients (88%) the degenerative changes were confined to the lateral compartment and contrasted with a normal appearance of the articular cartilage of the medial compartment. Primary lateral compartment arthritis is more common than previously thought, it mostly affects a young population and could easily be misdiagnosed as lateral epicondylitis.

  19. Current thinking about acute compartment syndrome of the lower extremity.

    PubMed

    Shadgan, Babak; Menon, Matthew; Sanders, David; Berry, Gregg; Martin, Claude; Duffy, Paul; Stephen, David; O'Brien, Peter J

    2010-10-01

    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.

  20. Arabidopsis EDS1 connects pathogen effector recognition to cell compartment-specific immune responses.

    PubMed

    Heidrich, Katharina; Wirthmueller, Lennart; Tasset, Céline; Pouzet, Cécile; Deslandes, Laurent; Parker, Jane E

    2011-12-01

    Pathogen effectors are intercepted by plant intracellular nucleotide binding-leucine-rich repeat (NB-LRR) receptors. However, processes linking receptor activation to downstream defenses remain obscure. Nucleo-cytoplasmic basal resistance regulator EDS1 (ENHANCED DISEASE SUSCEPTIBILITY1) is indispensible for immunity mediated by TIR (Toll-interleukin-1 receptor)-NB-LRR receptors. We show that Arabidopsis EDS1 molecularly connects TIR-NB-LRR disease resistance protein RPS4 recognition of bacterial effector AvrRps4 to defense pathways. RPS4-EDS1 and AvrRps4-EDS1 complexes are detected inside nuclei of living tobacco cells after transient coexpression and in Arabidopsis soluble leaf extracts after resistance activation. Forced AvrRps4 localization to the host cytoplasm or nucleus reveals cell compartment-specific RPS4-EDS1 defense branches. Although nuclear processes restrict bacterial growth, programmed cell death and transcriptional resistance reinforcement require nucleo-cytoplasmic coordination. Thus, EDS1 behaves as an effector target and activated TIR-NB-LRR signal transducer for defenses across cell compartments.

  1. Botulinum neurotoxin A and an engineered derivate targeted secretion inhibitor (TSI) A enter cells via different vesicular compartments.

    PubMed

    Fonfria, Elena; Donald, Sarah; Cadd, Verity A

    2016-01-01

    Botulinum neurotoxins (BoNTs) are highly potent multi-domain proteins, responsible for botulism in animals and humans. The modular structural organization of BoNTs has led to the development of novel engineered bio-therapeutic proteins called targeted secretion inhibitors (TSIs). We report here that botulinum neurotoxin A (BoNT/A) and a TSI/A in which the neuronal binding domain of BoNT/A has been substituted by an epidermal growth factor (EGF) ligand, named EGFR-targeted TSI/A, exploit different routes to gain entry in the same in vitro neuroblastoma cell system, SiMa cells. We found that the EGF ligand conferred the affinity to the EGFR-targeted TSI/A at the EGF receptor when compared to an untargeted TSI/A and also the ability to internalize into the cells and cleave its cytosolic target protein SNAP-25. Using high content analysis we found that both BoNT/A and the EGFR-targeted TSI/A enter the cell in a concentration-dependent manner and in compartments which are able to translocate the proteins into the cytosol within 4 h. The EGFR-targeted TSI/A internalized into a compartment which gave a punctate staining pattern by immunofluorescence and partially overlapped with structures positive for the early endosomal marker EAA1; whereas BoNT/A did not internalize into a punctate compartment but did so in an acidifying compartment consistent with local synaptic vesicle recycling. These findings show that the BoNT/A translocation domain, common to both BoNT/A and the EGFR-targeted TSI/A, is a versatile tool for cytosolic delivery from distinct intracellular vesicular compartments. PMID:26329879

  2. Toward intracellular targeted delivery of cancer therapeutics: progress and clinical outlook for brain tumor therapy.

    PubMed

    Pandya, Hetal; Debinski, Waldemar

    2012-08-01

    A number of anti-cancer drugs have their targets localized to particular intracellular compartments. These drugs reach the targets mainly through diffusion, dependent on biophysical and biochemical forces that allow cell penetration. This means that both cancer cells and normal cells will be subjected to such diffusion; hence many of these drugs, like chemotherapeutics, are potentially toxic and the concentration achieved at the site of their action is often suboptimal. The same relates to radiation that indiscriminately affects normal and diseased cells. However, nature-designed systems enable compounds present in the extracellular environment to end up inside the cell and even travel to more specific intracellular compartments. For example, viruses and bacterial toxins can more or less specifically recognize eukaryotic cells, enter these cells, and direct some protein portions to designated intracellular areas. These phenomena have led to creative thinking, such as employing viruses or bacterial toxins for cargo delivery to cells and, more specifically, to cancer cells. Proteins can be genetically engineered in order to not only mimic what viruses and bacterial toxins can do, but also to add new functions, extending or changing the intracellular routes. It is possible to make conjugates or, more preferably, single-chain proteins that recognize cancer cells and deliver cargo inside the cells, even to the desired subcellular compartment. These findings offer new opportunities to deliver drugs/labels only to cancer cells and only to their site of action within the cells. The development of such dual-specificity vectors for targeting cancer cells is an attractive and potentially safer and more efficacious way of delivering drugs. We provide examples of this approach for delivering brain cancer therapeutics, using a specific biomarker on glioblastoma tumor cells.

  3. Intracellular targeting of antigens internalized by membrane immunoglobulin in B lymphocytes.

    PubMed

    Mitchell, R N; Barnes, K A; Grupp, S A; Sanchez, M; Misulovin, Z; Nussenzweig, M C; Abbas, A K

    1995-05-01

    An important function of membrane immunoglobulin (mIg), the B cell antigen receptor, is to endocytose limiting quantities of antigen for efficient presentation to class II-restricted T cells. We have used a panel of mIg mutants to analyze the mechanism of mIg-mediated antigen presentation, and specifically to explore the ability of mIg to target internalized antigen to intracellular processing compartments. Transfected mIgs carrying substitutions for the transmembrane Tyr587 residue fail to efficiently present specifically bound antigen. However, these mutants internalize antigen normally, and their defect cannot be attributed to a lack of mIg-associated Ig alpha/Ig beta molecules. A novel functional assay for detecting antigenic peptides in subcellular fractions shows that wild-type mIg transfectants generate class II-peptide complexes intracellularly, whereas only free antigenic peptides are detectable in the mutant mIg transfectants. Furthermore, an antigen competition assay reveals that antigen internalized by the mutant mIgs fails to enter the intracellular processing compartment accessed by wild-type mIg. Therefore, mIg specifically targets bound and endocytosed antigen to the intracellular compartment where processed peptides associate with class II molecules, and the transmembrane Tyr587 residue plays an obligatory role in this process. Targeting of internalized antigen may be mediated by receptor-associated chaperones, and may be a general mechanism for optimizing the presentation of specifically bound and endocytosed antigens in b lymphocytes and other antigen-presenting cells.

  4. An earthquake instability model based on faults containing high fluid-pressure compartments

    USGS Publications Warehouse

    Lockner, D.A.; Byerlee, J.D.

    1995-01-01

    It has been proposed that large strike-slip faults such as the San Andreas contain water in seal-bounded compartments. Arguments based on heat flow and stress orientation suggest that in most of the compartments, the water pressure is so high that the average shear strength of the fault is less than 20 MPa. We propose a variation of this basic model in which most of the shear stress on the fault is supported by a small number of compartments where the pore pressure is relatively low. As a result, the fault gouge in these compartments is compacted and lithified and has a high undisturbed strength. When one of these locked regions fails, the system made up of the neighboring high and low pressure compartments can become unstable. Material in the high fluid pressure compartments is initially underconsolidated since the low effective confining pressure has retarded compaction. As these compartments are deformed, fluid pressure remains nearly unchanged so that they offer little resistance to shear. The low pore pressure compartments, however, are overconsolidated and dilate as they are sheared. Decompression of the pore fluid in these compartments lowers fluid pressure, increasing effective normal stress and shear strength. While this effect tends to stabilize the fault, it can be shown that this dilatancy hardening can be more than offset by displacement weakening of the fault (i.e., the drop from peak to residual strength). If the surrounding rock mass is sufficiently compliant to produce an instability, slip will propagate along the fault until the shear fracture runs into a low-stress region. Frictional heating and the accompanying increase in fluid pressure that are suggested to occur during shearing of the fault zone will act as additional destabilizers. However, significant heating occurs only after a finite amount of slip and therefore is more likely to contribute to the energetics of rupture propagation than to the initiation of the instability. We present

  5. Magnetic tweezers for intracellular applications

    NASA Astrophysics Data System (ADS)

    Hosu, Basarab G.; Jakab, Károly; Bánki, Péter; Tóth, Ferenc I.; Forgacs, Gabor

    2003-09-01

    We have designed and constructed a versatile magnetic tweezer primarily for intracellular investigations. The micromanipulator uses only two coils to simultaneously magnetize to saturation micron-size superparamagnetic particles and generate high magnitude constant field gradients over cellular dimensions. The apparatus resembles a miniaturized Faraday balance, an industrial device used to measure magnetic susceptibility. The device operates in both continuous and pulse modes. Due to its compact size, the tweezers can conveniently be mounted on the stage of an inverted microscope and used for intracellular manipulations. A built-in temperature control unit maintains the sample at physiological temperatures. The operation of the tweezers was tested by moving 1.28 μm diameter magnetic beads inside macrophages with forces near 500 pN.

  6. Direct Measurement of Intracellular Pressure

    PubMed Central

    Petrie, Ryan J.; Koo, Hyun

    2014-01-01

    A method to directly measure the intracellular pressure of adherent, migrating cells is described in the Basic Protocol. This approach is based on the servo-null method where a microelectrode is introduced into the cell to directly measure the physical pressure of the cytoplasm. We also describe the initial calibration of the microelectrode as well as the application of the method to cells migrating inside three-dimensional (3D) extracellular matrix (ECM). PMID:24894836

  7. Stochastic models of intracellular transport

    NASA Astrophysics Data System (ADS)

    Bressloff, Paul C.; Newby, Jay M.

    2013-01-01

    The interior of a living cell is a crowded, heterogenuous, fluctuating environment. Hence, a major challenge in modeling intracellular transport is to analyze stochastic processes within complex environments. Broadly speaking, there are two basic mechanisms for intracellular transport: passive diffusion and motor-driven active transport. Diffusive transport can be formulated in terms of the motion of an overdamped Brownian particle. On the other hand, active transport requires chemical energy, usually in the form of adenosine triphosphate hydrolysis, and can be direction specific, allowing biomolecules to be transported long distances; this is particularly important in neurons due to their complex geometry. In this review a wide range of analytical methods and models of intracellular transport is presented. In the case of diffusive transport, narrow escape problems, diffusion to a small target, confined and single-file diffusion, homogenization theory, and fractional diffusion are considered. In the case of active transport, Brownian ratchets, random walk models, exclusion processes, random intermittent search processes, quasi-steady-state reduction methods, and mean-field approximations are considered. Applications include receptor trafficking, axonal transport, membrane diffusion, nuclear transport, protein-DNA interactions, virus trafficking, and the self-organization of subcellular structures.

  8. Glycosaminoglycans: Sorting determinants in intracellular protein traffic.

    PubMed

    Mihov, Deyan; Spiess, Martin

    2015-11-01

    Intracellular transport of proteins to their appropriate destinations is crucial for the maintenance of cellular integrity and function. Sorting information is contained either directly in the amino acid sequence or in a protein's post-translational modifications. Glycosaminoglycans (GAGs) are characteristic modifications of proteoglycans. GAGs are long unbranched polysaccharide chains with unique structural and functional properties also contributing to protein sorting in various ways. By deletion or insertion of GAG attachment sites it has been shown that GAGs affect polarized sorting in epithelial cells, targeting to and storage in secretory granules, and endocytosis. Most recently, the role of GAGs as signals for rapid trans-Golgi-to-cell surface transport, dominant over the cytosolic sorting motifs in the core protein, was demonstrated. Here, we provide an overview on existing data on the roles of GAGs on protein and proteoglycan trafficking.

  9. 3. INCLINE PLANE CAR INTERIOR, UPPER COMPARTMENT. Monongahela Incline ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. INCLINE PLANE CAR INTERIOR, UPPER COMPARTMENT. - Monongahela Incline Plane, Connecting North side of Grandview Avenue at Wyoming Street with West Carson Street near Smithfield Street, Pittsburgh, Allegheny County, PA

  10. 11. Interior view of communications compartment. View toward rear of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Interior view of communications compartment. View toward rear of aircraft. - Offutt Air Force Base, Looking Glass Airborne Command Post, Looking Glass Aircraft, On Operational Apron covering northeast half of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  11. 10. Interior view of communications compartment. View toward front of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Interior view of communications compartment. View toward front of aircraft. - Offutt Air Force Base, Looking Glass Airborne Command Post, Looking Glass Aircraft, On Operational Apron covering northeast half of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  12. 9. Interior view of electronics compartment. View toward rear of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Interior view of electronics compartment. View toward rear of aircraft. - Offutt Air Force Base, Looking Glass Airborne Command Post, Looking Glass Aircraft, On Operational Apron covering northeast half of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  13. 14 CFR 23.787 - Baggage and cargo compartments.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... critical load distributions at the appropriate maximum load factors corresponding to the flight and ground... any compartment, located aft of the occupants and separated by structure, when the ultimate...

  14. 14 CFR 23.787 - Baggage and cargo compartments.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... critical load distributions at the appropriate maximum load factors corresponding to the flight and ground... any compartment, located aft of the occupants and separated by structure, when the ultimate...

  15. 14 CFR 23.787 - Baggage and cargo compartments.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... critical load distributions at the appropriate maximum load factors corresponding to the flight and ground... any compartment, located aft of the occupants and separated by structure, when the ultimate...

  16. 14 CFR 23.853 - Passenger and crew compartment interiors.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... fabrics, leather, trays and galley furnishings, electrical conduit, thermal and acoustical insulation and insulation covering, air ducting, joint and edge covering, cargo compartment liners, insulation blankets... cable insulation, and for small parts (such as knobs, handles, rollers, fasteners, clips, grommets,...

  17. 113. INTERIOR COMMUNICATIONS COMPARTMENT PORT LOOKING TO STARBOARD SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    113. INTERIOR COMMUNICATIONS COMPARTMENT - PORT LOOKING TO STARBOARD SHOWING MASTER GYRO AND INTERIOR COMMUNICATIONS SWITCHBOARD. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA

  18. FEATURE 3, LARGE GUN POSITION, SHOWING MULTIPLE COMPARTMENTS, VIEW FACING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    FEATURE 3, LARGE GUN POSITION, SHOWING MULTIPLE COMPARTMENTS, VIEW FACING SOUTH. - Naval Air Station Barbers Point, Anti-Aircraft Battery Complex-Large Gun Position, East of Coral Sea Road, northwest of Hamilton Road, Ewa, Honolulu County, HI

  19. 19 CFR 123.24 - Sealing of conveyances or compartments.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...; DEPARTMENT OF THE TREASURY CUSTOMS RELATIONS WITH CANADA AND MEXICO Shipments in Transit Through Canada or Mexico § 123.24 Sealing of conveyances or compartments. (a) Sealing required. Merchandise in...

  20. Turbofan Engine Core Compartment Vent Aerodynamic Configuration Development Methodology

    NASA Technical Reports Server (NTRS)

    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.

  1. 2. INTERIOR, SOUTHWEST VIEW (STORAGE COMPARTMENTS). Vanadium Corporation of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. INTERIOR, SOUTHWEST VIEW (STORAGE COMPARTMENTS). - Vanadium Corporation of America (VCA) Naturita Mill, Mine Warehouse, 3 miles Northwest of Naturita, between Highway 141 & San Miguel River, Naturita, Montrose County, CO

  2. Two clinical tests for assessing lateral compartment arthritis.

    PubMed

    Shakespeare, David

    2006-08-01

    Two clinical tests, the valgus tap test and the valgus skid test, are described which detect bone contact in the lateral compartment of the knee. They are useful in planning surgical intervention. PMID:16632364

  3. Dynamics of the Establishment of Multinucleate Compartments in Fusarium oxysporum

    PubMed Central

    Shahi, Shermineh; Beerens, Bas; Manders, Erik M. M.

    2014-01-01

    Nuclear dynamics can vary widely between fungal species and between stages of development of fungal colonies. Here we compared nuclear dynamics and mitotic patterns between germlings and mature hyphae in Fusarium oxysporum. Using fluorescently labeled nuclei and live-cell imaging, we show that F. oxysporum is subject to a developmental transition from a uninucleate to a multinucleate state after completion of colony initiation. We observed a special type of hypha that exhibits a higher growth rate, possibly acting as a nutrient scout. The higher growth rate is associated with a higher nuclear count and mitotic waves involving 2 to 6 nuclei in the apical compartment. Further, we found that dormant nuclei of intercalary compartments can reenter the mitotic cycle, resulting in multinucleate compartments with up to 18 nuclei in a single compartment. PMID:25398376

  4. Compartment syndrome: a complication of acute extremity trauma.

    PubMed

    Mabee, J R

    1994-01-01

    Compartment syndrome is a serious potential complication of trauma to the extremities. Fractures, crush injuries, burns, and arterial injuries, among others, can result in increased tissue pressure within closed osseofascial or compartmental spaces. Prolonged exposure to elevated pressure can result in nerve and muscle necrosis. Extreme pain unrelieved with analgesia, subjective complaint of pressure, pain with passive muscle stretching, paresis, paresthesia, and intact pulses, in the presence of a physically tight compartment, should alert the physician to the presence of a compartment syndrome. The diagnosis is a clinical one, but it may be aided by measurements of intracompartmental tissue pressures. Compartment syndrome is a surgical emergency requiring prompt treatment by fasciotomy. Time is a critical factor; the longer the duration of elevated tissue pressure, the greater the potential for disastrous sequelae. Emergency medicine providers must be cognizant of this clinical syndrome so that early emergent surgical consultation can be obtained to avoid complications.

  5. Diagnosis and treatment of acute extremity compartment syndrome.

    PubMed

    von Keudell, Arvind G; Weaver, Michael J; Appleton, Paul T; Appelton, Paul T; Bae, Donald S; Dyer, George S M; Heng, Marilyn; Jupiter, Jesse B; Vrahas, Mark S

    2015-09-26

    Acute compartment syndrome of the extremities is well known, but diagnosis can be challenging. Ineffective treatment can have devastating consequences, such as permanent dysaesthesia, ischaemic contractures, muscle dysfunction, loss of limb, and even loss of life. Despite many studies, there is no consensus about the way in which acute extremity compartment syndromes should be diagnosed. Many surgeons suggest continuous monitoring of intracompartmental pressure for all patients who have high-risk extremity injuries, whereas others suggest aggressive surgical intervention if acute compartment syndrome is even suspected. Although surgical fasciotomy might reduce intracompartmental pressure, this procedure also carries the risk of long-term complications. In this paper in The Lancet Series about emergency surgery we summarise the available data on acute extremity compartment syndrome of the upper and lower extremities in adults and children, discuss the underlying pathophysiology, and propose a clinical guideline based on the available data.

  6. Propofol extravasation: a rare cause of compartment syndrome.

    PubMed

    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.

  7. Abdominal Compartment Syndrome: Risk Factors, Diagnosis, and Current Therapy

    PubMed Central

    Luckianow, Gina M.; Ellis, Matthew; Governale, Deborah; Kaplan, Lewis J.

    2012-01-01

    Abdominal compartment syndrome's manifestations are difficult to definitively detect on physical examination alone. Therefore, objective criteria have been articulated that aid the bedside clinician in detecting intra-abdominal hypertension as well as the abdominal compartment syndrome to initiate prompt and potentially life-saving intervention. At-risk patient populations should be routinely monitored and tiered interventions should be undertaken as a team approach to management. PMID:22720147

  8. Acute pediatric leg compartment syndrome in chronic myeloid leukemia.

    PubMed

    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. PMID:25361367

  9. Acute pediatric leg compartment syndrome in chronic myeloid leukemia.

    PubMed

    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.

  10. Intracellular calcium signals regulate growth of hepatic stellate cells via specific effects on cell cycle progression

    PubMed Central

    Soliman, Elwy M.; Rodrigues, Michele Angela; Gomes, Dawidson Assis; Sheung, Nina; Yu, Jin; Amaya, Maria Jimina; Nathanson, Michael H.; Dranoff, Jonathan A.

    2010-01-01

    Hepatic stellate cells (HSC) are important mediators of liver fibrosis. Hormones linked to downstream intracellular Ca2+ signals upregulate HSC proliferation, but the mechanisms by which this occurs are unknown. Nuclear and cytosolic Ca2+ signals may have distinct effects on cell proliferation, so we expressed plasmid and adenoviral constructs containing the Ca2+ chelator parvalbumin (PV) linked to either a nuclear localization sequence (NLS) or a nuclear export sequence (NES) to block Ca2+ signals in distinct compartments within LX-2 immortalized human HSC and primary rat HSC. PV-NLS and PV-NES constructs each targeted to the appropriate intracellular compartment and blocked Ca2+ signals only within that compartment. PV-NLS and PV-NES constructs inhibited HSC growth. Furthermore, blockade of nuclear or cytosolic Ca2+ signals arrested growth at the G2/mitosis (G2/M) cell-cycle interface and prevented the onset of mitosis. Blockade of nuclear or cytosolic Ca2+ signals downregulated phosphorylation of the G2/M checkpoint phosphatase Cdc25C. Inhibition of calmodulin kinase II (CaMK II) had identical effects on LX-2 growth and Cdc25C phosphorylation. We propose that nuclear and cytosolic Ca2+ are critical signals that regulate HSC growth at the G2/M checkpoint via CaMK II-mediated regulation of Cdc25C phosphorylation. These data provide a new logical target for pharmacological therapy directed against progression of liver fibrosis. PMID:19131107

  11. Fluorescent nanosensors for intracellular measurements: synthesis, characterization, calibration, and measurement

    PubMed Central

    Desai, Arpan S.; Chauhan, Veeren M.; Johnston, Angus P. R.; Esler, Tim; Aylott, Jonathan W.

    2013-01-01

    Measurement of intracellular acidification is important for understanding fundamental biological pathways as well as developing effective therapeutic strategies. Fluorescent pH nanosensors are an enabling technology for real-time monitoring of intracellular acidification. The physicochemical characteristics of nanosensors can be engineered to target specific cellular compartments and respond to external stimuli. Therefore, nanosensors represent a versatile approach for probing biological pathways inside cells. The fundamental components of nanosensors comprise a pH-sensitive fluorophore (signal transducer) and a pH-insensitive reference fluorophore (internal standard) immobilized in an inert non-toxic matrix. The inert matrix prevents interference of cellular components with the sensing elements as well as minimizing potentially harmful effects of some fluorophores on cell function. Fluorescent nanosensors are synthesized using standard laboratory equipment and are detectable by non-invasive widely accessible imaging techniques. The outcomes of studies employing this technology are dependent on reliable methodology for performing measurements. In particular, special consideration must be given to conditions for sensor calibration, uptake conditions and parameters for image analysis. We describe procedures for: (1) synthesis and characterization of polyacrylamide and silica based nanosensors, (2) nanosensor calibration and (3) performing measurements using fluorescence microscopy. PMID:24474936

  12. Uptake and intracellular trafficking of superantigens in dendritic cells.

    PubMed

    Ganem, María B; De Marzi, Mauricio C; Fernández-Lynch, María J; Jancic, Carolina; Vermeulen, Mónica; Geffner, Jorge; Mariuzza, Roy A; Fernández, Marisa M; Malchiodi, Emilio L

    2013-01-01

    Bacterial superantigens (SAgs) are exotoxins produced mainly by Staphylococcus aureus and Streptococcus pyogenes that can cause toxic shock syndrome (TSS). According to current paradigm, SAgs interact directly and simultaneously with T cell receptor (TCR) on the T cell and MHC class II (MHC-II) on the antigen-presenting cell (APC), thereby circumventing intracellular processing to trigger T cell activation. Dendritic cells (DCs) are professional APCs that coat nearly all body surfaces and are the most probable candidate to interact with SAgs. We demonstrate that SAgs are taken up by mouse DCs without triggering DC maturation. SAgs were found in intracellular acidic compartment of DCs as biologically active molecules. Moreover, SAgs co-localized with EEA1, RAB-7 and LAMP-2, at different times, and were then recycled to the cell membrane. DCs loaded with SAgs are capable of triggering in vitro lymphocyte proliferation and, injected into mice, stimulate T cells bearing the proper TCR in draining lymph nodes. Transportation and trafficking of SAgs in DCs might increase the local concentration of these exotoxins where they will produce the highest effect by promoting their encounter with both MHC-II and TCR in lymph nodes, and may explain how just a few SAg molecules can induce the severe pathology associated with TSS. PMID:23799083

  13. Uptake and Intracellular Trafficking of Superantigens in Dendritic Cells

    PubMed Central

    Fernández-Lynch, María J.; Jancic, Carolina; Vermeulen, Mónica; Geffner, Jorge; Mariuzza, Roy A.; Fernández, Marisa M.; Malchiodi, Emilio L.

    2013-01-01

    Bacterial superantigens (SAgs) are exotoxins produced mainly by Staphylococcus aureus and Streptococcus pyogenes that can cause toxic shock syndrome (TSS). According to current paradigm, SAgs interact directly and simultaneously with T cell receptor (TCR) on the T cell and MHC class II (MHC-II) on the antigen-presenting cell (APC), thereby circumventing intracellular processing to trigger T cell activation. Dendritic cells (DCs) are professional APCs that coat nearly all body surfaces and are the most probable candidate to interact with SAgs. We demonstrate that SAgs are taken up by mouse DCs without triggering DC maturation. SAgs were found in intracellular acidic compartment of DCs as biologically active molecules. Moreover, SAgs co-localized with EEA1, RAB-7 and LAMP-2, at different times, and were then recycled to the cell membrane. DCs loaded with SAgs are capable of triggering in vitro lymphocyte proliferation and, injected into mice, stimulate T cells bearing the proper TCR in draining lymph nodes. Transportation and trafficking of SAgs in DCs might increase the local concentration of these exotoxins where they will produce the highest effect by promoting their encounter with both MHC-II and TCR in lymph nodes, and may explain how just a few SAg molecules can induce the severe pathology associated with TSS. PMID:23799083

  14. Simultaneous pH measurement in endocytic and cytosolic compartments in living cells using confocal microscopy.

    PubMed

    Lucien, Fabrice; Harper, Kelly; Pelletier, Pierre-Paul; Volkov, Leonid; Dubois, Claire M

    2014-01-01

    Intracellular pH is tightly regulated and differences in pH between the cytoplasm and organelles have been reported(1). Regulation of cellular pH is crucial for homeostatic control of physiological processes that include: protein, DNA and RNA synthesis, vesicular trafficking, cell growth and cell division. Alterations in cellular pH homeostasis can lead to detrimental functional changes and promote progression of various diseases(2). Various methods are available for measuring intracellular pH but very few of these allow simultaneous measurement of pH in the cytoplasm and in organelles. Here, we describe in detail a rapid and accurate method for the simultaneous measurement of cytoplasmic and organellar pH by using confocal microscopy on living cells(3). This goal is achieved with the use of two pH-sensing ratiometric dyes that possess selective cellular compartment partitioning. For instance, SNARF-1 is compartmentalized inside the cytoplasm whereas HPTS is compartmentalized inside endosomal/lysosomal organelles. Although HPTS is commonly used as a cytoplasmic pH indicator, this dye can specifically label vesicles along the endosomal-lysosomal pathway after being taken up by pinocytosis(3,4). Using these pH-sensing probes, it is possible to simultaneously measure pH within the endocytic and cytoplasmic compartments. The optimal excitation wavelength of HPTS varies depending on the pH while for SNARF-1, it is the optimal emission wavelength that varies. Following loading with SNARF-1 and HPTS, cells are cultured in different pH-calibrated solutions to construct a pH standard curve for each probe. Cell imaging by confocal microscopy allows elimination of artifacts and background noise. Because of the spectral properties of HPTS, this probe is better suited for measurement of the mildly acidic endosomal compartment or to demonstrate alkalinization of the endosomal/lysosomal organelles. This method simplifies data analysis, improves accuracy of pH measurements and can

  15. Simultaneous pH Measurement in Endocytic and Cytosolic Compartments in Living Cells using Confocal Microscopy

    PubMed Central

    Lucien, Fabrice; Harper, Kelly; Pelletier, Pierre-Paul; Volkov, Leonid; Dubois, Claire M.

    2014-01-01

    Intracellular pH is tightly regulated and differences in pH between the cytoplasm and organelles have been reported1. Regulation of cellular pH is crucial for homeostatic control of physiological processes that include: protein, DNA and RNA synthesis, vesicular trafficking, cell growth and cell division. Alterations in cellular pH homeostasis can lead to detrimental functional changes and promote progression of various diseases2. Various methods are available for measuring intracellular pH but very few of these allow simultaneous measurement of pH in the cytoplasm and in organelles. Here, we describe in detail a rapid and accurate method for the simultaneous measurement of cytoplasmic and organellar pH by using confocal microscopy on living cells3. This goal is achieved with the use of two pH-sensing ratiometric dyes that possess selective cellular compartment partitioning. For instance, SNARF-1 is compartmentalized inside the cytoplasm whereas HPTS is compartmentalized inside endosomal/lysosomal organelles. Although HPTS is commonly used as a cytoplasmic pH indicator, this dye can specifically label vesicles along the endosomal-lysosomal pathway after being taken up by pinocytosis3,4. Using these pH-sensing probes, it is possible to simultaneously measure pH within the endocytic and cytoplasmic compartments. The optimal excitation wavelength of HPTS varies depending on the pH while for SNARF-1, it is the optimal emission wavelength that varies. Following loading with SNARF-1 and HPTS, cells are cultured in different pH-calibrated solutions to construct a pH standard curve for each probe. Cell imaging by confocal microscopy allows elimination of artifacts and background noise. Because of the spectral properties of HPTS, this probe is better suited for measurement of the mildly acidic endosomal compartment or to demonstrate alkalinization of the endosomal/lysosomal organelles. This method simplifies data analysis, improves accuracy of pH measurements and can be used

  16. Reorganization of the Endosomal System in Salmonella-Infected Cells: The Ultrastructure of Salmonella-Induced Tubular Compartments

    PubMed Central

    Krieger, Viktoria; Liebl, David; Zhang, Yuying; Rajashekar, Roopa; Chlanda, Petr; Giesker, Katrin; Chikkaballi, Deepak; Hensel, Michael

    2014-01-01

    During the intracellular life of Salmonella enterica, a unique membrane-bound compartment termed Salmonella-containing vacuole, or SCV, is formed. By means of translocated effector proteins, intracellular Salmonella also induce the formation of extensive, highly dynamic membrane tubules termed Salmonella-induced filaments or SIF. Here we report the first detailed ultrastructural analyses of the SCV and SIF by electron microscopy (EM), EM tomography and live cell correlative light and electron microscopy (CLEM). We found that a subset of SIF is composed of double membranes that enclose portions of host cell cytosol and cytoskeletal filaments within its inner lumen. Despite some morphological similarities, we found that the formation of SIF double membranes is independent from autophagy and requires the function of the effector proteins SseF and SseG. The lumen of SIF network is accessible to various types of endocytosed material and our CLEM analysis of double membrane SIF demonstrated that fluid phase markers accumulate only between the inner and outer membrane of these structures, a space continual with endosomal lumen. Our work reveals how manipulation of the endosomal membrane system by an intracellular pathogen results in a unique tubular membrane compartmentalization of the host cell, generating a shielded niche permissive for intracellular proliferation of Salmonella. PMID:25254663

  17. Reorganization of the endosomal system in Salmonella-infected cells: the ultrastructure of Salmonella-induced tubular compartments.

    PubMed

    Krieger, Viktoria; Liebl, David; Zhang, Yuying; Rajashekar, Roopa; Chlanda, Petr; Giesker, Katrin; Chikkaballi, Deepak; Hensel, Michael

    2014-09-01

    During the intracellular life of Salmonella enterica, a unique membrane-bound compartment termed Salmonella-containing vacuole, or SCV, is formed. By means of translocated effector proteins, intracellular Salmonella also induce the formation of extensive, highly dynamic membrane tubules termed Salmonella-induced filaments or SIF. Here we report the first detailed ultrastructural analyses of the SCV and SIF by electron microscopy (EM), EM tomography and live cell correlative light and electron microscopy (CLEM). We found that a subset of SIF is composed of double membranes that enclose portions of host cell cytosol and cytoskeletal filaments within its inner lumen. Despite some morphological similarities, we found that the formation of SIF double membranes is independent from autophagy and requires the function of the effector proteins SseF and SseG. The lumen of SIF network is accessible to various types of endocytosed material and our CLEM analysis of double membrane SIF demonstrated that fluid phase markers accumulate only between the inner and outer membrane of these structures, a space continual with endosomal lumen. Our work reveals how manipulation of the endosomal membrane system by an intracellular pathogen results in a unique tubular membrane compartmentalization of the host cell, generating a shielded niche permissive for intracellular proliferation of Salmonella.

  18. Intracellular trafficking of silicon particles and logic-embedded vectors

    NASA Astrophysics Data System (ADS)

    Ferrati, Silvia; Mack, Aaron; Chiappini, Ciro; Liu, Xuewu; Bean, Andrew J.; Ferrari, Mauro; Serda, Rita E.

    2010-08-01

    Mesoporous silicon particles show great promise for use in drug delivery and imaging applications as carriers for second-stage nanoparticles and higher order particles or therapeutics. Modulation of particle geometry, surface chemistry, and porosity allows silicon particles to be optimized for specific applications such as vascular targeting and avoidance of biological barriers commonly found between the site of drug injection and the final destination. In this study, the intracellular trafficking of unloaded carrier silicon particles and carrier particles loaded with secondary iron oxide nanoparticles was investigated. Following cellular uptake, membrane-encapsulated silicon particles migrated to the perinuclear region of the cell by a microtubule-driven mechanism. Surface charge, shape (spherical and hemispherical) and size (1.6 and 3.2 μm) of the particle did not alter the rate of migration. Maturation of the phagosome was associated with an increase in acidity and acquisition of markers of late endosomes and lysosomes. Cellular uptake of iron oxide nanoparticle-loaded silicon particles resulted in sorting of the particles and trafficking to unique destinations. The silicon carriers remained localized in phagosomes, while the second stage iron oxide nanoparticles were sorted into multi-vesicular bodies that dissociated from the phagosome into novel membrane-bound compartments. Release of iron from the cells may represent exocytosis of iron oxide nanoparticle-loaded vesicles. These results reinforce the concept of multi-functional nanocarriers, in which different particles are able to perform specific tasks, in order to deliver single- or multi-component payloads to specific sub-cellular compartments.Mesoporous silicon particles show great promise for use in drug delivery and imaging applications as carriers for second-stage nanoparticles and higher order particles or therapeutics. Modulation of particle geometry, surface chemistry, and porosity allows silicon

  19. Intracellular insulin processing is altered in monocytes from patients with type II diabetes mellitus

    SciTech Connect

    Trischitta, V.; Benzi, L.; Brunetti, A.; Cecchetti, P.; Marchetti, P.; Vigneri, R.; Navalesi, R.

    1987-05-01

    We studied total cell-associated A14-(/sup 125/I)insulin radioactivity (including surface-bound and internalized radioactivity), insulin internalization, and its intracellular degradation at 37 C in monocytes from nonobese type II untreated diabetic patients (n = 9) and normal subjects (n = 7). Total cell-associated radioactivity was decreased in diabetic patients (2.65 +/- 1.21% (+/- SD) vs. 4.47 +/- 1.04% of total radioactivity. Insulin internalization was also reduced in diabetic patients (34.0 +/- 6.8% vs. 59.0 +/- 11.3% of cell-associated radioactivity. Using high performance liquid chromatography six intracellular forms of radioactivity derived from A14-(/sup 125/I) insulin were identified; 10-20% of intracellular radioactivity had approximately 300,000 mol wt and was identified as radioactivity bound to the insulin receptor, and the remaining intracellular radioactivity included intact A14-(/sup 125/I)insulin, (/sup 125/I)iodide, or (/sup 125/I)tyrosine, and three intermediate compounds. A progressive reduction of intact insulin and a corresponding increase in iodine were found when the incubation time was prolonged. Intracellular insulin degradation was reduced in monocytes from diabetic patients; intracellular intact insulin was 65.6 +/- 18.1% vs. 37.4 +/- 18.0% of intracellular radioactivity after 2 min and 23.6 +/- 22.3% vs. 3.9 +/- 2.3% after 60 min in diabetic patients vs. normal subjects, respectively. In conclusion, 1) human monocytes internalize and degrade insulin in the intracellular compartment in a stepwise time-dependent manner; and 2) in monocytes from type II diabetic patients total cell-associated radioactivity, insulin internalization, and insulin degradation are significantly reduced. These defects may be related to the cellular insulin resistance present in these patients.

  20. Urothelial cultures support intracellular bacterial community formation by uropathogenic Escherichia coli.

    PubMed

    Berry, Ruth E; Klumpp, David J; Schaeffer, Anthony J

    2009-07-01

    Uropathogenic Escherichia coli (UPEC) causes most community-acquired and nosocomial urinary tract infections (UTI). In a mouse model of UTI, UPEC invades superficial bladder cells and proliferates rapidly, forming biofilm-like structures called intracellular bacterial communities (IBCs). Using a gentamicin protection assay and fluorescence microscopy, we developed an in vitro model for studying UPEC proliferation within immortalized human urothelial cells. By pharmacologic manipulation of urothelial cells with the cholesterol-sequestering drug filipin, numbers of intracellular UPEC CFU increased 8 h and 24 h postinfection relative to untreated cultures. Enhanced UPEC intracellular proliferation required that the urothelial cells, but not the bacteria, be filipin treated prior to infection. However, neither UPEC frequency of invasion nor early intracellular trafficking events to a Lamp1-positive compartment were modulated by filipin. Upon inspection by fluorescence microscopy, cultures with enhanced UPEC intracellular proliferation exhibited large, dense bacterial aggregates within cells that resembled IBCs but were contained with Lamp1-positive vacuoles. While an isogenic fimH mutant was capable of forming these IBC-like structures, the mutant formed significantly fewer than wild-type UPEC. Similar to IBCs, expression of E. coli iron acquisition systems was upregulated by intracellular UPEC. Expression of other putative virulence factors, including hlyA, cnf1, fliC, kpsD, and the biofilm adhesin yfaL also increased, while expression of fimA decreased and that of flu did not change. These results indicate that UPEC differentially regulates virulence factors in the intracellular environment. Thus, immortalized urothelial cultures that recapitulate IBC formation in vitro represent a novel system for the molecular and biochemical characterization of the UPEC intracellular life cycle.

  1. Inter- and intra-patient clonal and subclonal heterogeneity of chronic lymphocytic leukaemia: evidences from circulating and lymph nodal compartments.

    PubMed

    Del Giudice, Ilaria; Marinelli, Marilisa; Wang, Jiguang; Bonina, Silvia; Messina, Monica; Chiaretti, Sabina; Ilari, Caterina; Cafforio, Luciana; Raponi, Sara; Mauro, Francesca R; Di Maio, Valeria; De Propris, Maria S; Nanni, Mauro; Ciardullo, Carmela; Rossi, Davide; Gaidano, Gianluca; Guarini, Anna; Rabadan, Raul; Foà, Robin

    2016-02-01

    Whole exome sequencing and copy number aberration (CNA) analysis were performed on cells taken from peripheral blood (PB) and lymph nodes (LN) of patients with chronic lymphocytic leukaemia (CLL). Of 64 non-silent somatic mutations, 54 (84·4%) were clonal in both compartments, 3 (4·7%) were PB-specific and 7 (10·9%) were LN-specific. Most of the LN- or PB-specific mutations were subclonal in the other corresponding compartment (variant frequency 0·5-5·3%). Of 41 CNAs, 27 (65·8%) were shared by both compartments and 7 (17·1%) were LN- or PB-specific. Overall, 6 of 9 cases (66·7%) showed genomic differences between the compartments. At subsequent relapse, Case 10, with 6 LN-specific lesions, and Case 100, with 6 LN-specific and 8 PB-specific lesions, showed, in the PB, the clonal expansion of LN-derived lesions with an adverse impact: SF3B1 mutation, BIRC3 deletion, del8(p23·3-p11·1), del9(p24·3-p13·1) and gain 2(p25·3-p14). CLL shows an intra-patient clonal heterogeneity according to the disease compartment, with both LN and PB-specific mutations/CNAs. The LN microenvironment might contribute to the clonal selection of unfavourable lesions, as LN-derived mutations/CNAs can appear in the PB at relapse.

  2. The role of each compartment in a two-compartment vertical flow reactor for ferruginous mine water treatment.

    PubMed

    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. PMID:24929991

  3. Legionella pneumophilaRequires Polyamines for Optimal Intracellular Growth ▿

    PubMed Central

    Nasrallah, Gheyath K.; Riveroll, Angela L.; Chong, Audrey; Murray, Lois E.; Lewis, P. Jeffrey; Garduño, Rafael A.

    2011-01-01

    The Gram-negative intracellular pathogen Legionella pneumophilareplicates in a membrane-bound compartment known as the Legionella-containing vacuole (LCV), into which it abundantly releases its chaperonin, HtpB. To determine whether HtpB remains within the LCV or reaches the host cell cytoplasm, we infected U937 human macrophages and CHO cells with L. pneumophilaexpressing a translocation reporter consisting of the Bordetella pertussisadenylate cyclase fused to HtpB. These infections led to increased cyclic AMP levels, suggesting that HtpB reaches the host cell cytoplasm. To identify potential functions of cytoplasmic HtpB, we expressed it in the yeast Saccharomyces cerevisiae, where HtpB induced pseudohyphal growth. A yeast-two-hybrid screen showed that HtpB interacted with S-adenosylmethionine decarboxylase (SAMDC), an essential yeast enzyme (encoded by SPE2) that is required for polyamine biosynthesis. Increasing the copy number of SPE2induced pseudohyphal growth in S. cerevisiae; thus, we speculated that (i) HtpB induces pseudohyphal growth by activating polyamine synthesis and (ii) L. pneumophilamay require exogenous polyamines for growth. A pharmacological inhibitor of SAMDC significantly reduced L. pneumophilareplication in L929 mouse cells and U937 macrophages, whereas exogenously added polyamines moderately favored intracellular growth, confirming that polyamines and host SAMDC activity promote L. pneumophilaproliferation. Bioinformatic analysis revealed that most known enzymes required for polyamine biosynthesis in bacteria (including SAMDC) are absent in L. pneumophila, further suggesting a need for exogenous polyamines. We hypothesize that HtpB may function to ensure a supply of polyamines in host cells, which are required for the optimal intracellular growth of L. pneumophila. PMID:21742865

  4. Legionella pneumophila requires polyamines for optimal intracellular growth.

    PubMed

    Nasrallah, Gheyath K; Riveroll, Angela L; Chong, Audrey; Murray, Lois E; Lewis, P Jeffrey; Garduño, Rafael A

    2011-09-01

    The Gram-negative intracellular pathogen Legionella pneumophila replicates in a membrane-bound compartment known as the Legionella-containing vacuole (LCV), into which it abundantly releases its chaperonin, HtpB. To determine whether HtpB remains within the LCV or reaches the host cell cytoplasm, we infected U937 human macrophages and CHO cells with L. pneumophila expressing a translocation reporter consisting of the Bordetella pertussisa denylate cyclase fused to HtpB. These infections led to increased cyclic AMP levels, suggesting that HtpB reaches the host cell cytoplasm. To identify potential functions of cytoplasmic HtpB, we expressed it in the yeast Saccharomyces cerevisiae, where HtpB induced pseudohyphal growth. A yeast-two-hybrid screen showed that HtpB interacted with S-adenosylmethionine decarboxylase (SAMDC), an essential yeast enzyme (encoded by SPE2) that is required for polyamine biosynthesis. Increasing the copy number of SPE2 induced pseudohyphal growth in S. cerevisiae; thus, we speculated that (i) HtpB induces pseudohyphal growth by activating polyamine synthesis and (ii) L. pneumophila may require exogenous polyamines for growth. A pharmacological inhibitor of SAMDC significantly reduced L. pneumophila replication in L929 mouse cells and U937 macrophages, whereas exogenously added polyamines moderately favored intracellular growth, confirming that polyamines and host SAMDC activity promote L. pneumophila proliferation. Bioinformatic analysis revealed that most known enzymes required for polyamine biosynthesis in bacteria (including SAMDC) are absent in L. pneumophila, further suggesting a need for exogenous polyamines. We hypothesize that HtpB may function to ensure a supply of polyamines in host cells, which are required for the optimal intracellular growth of L. pneumophila.

  5. Legionella pneumophila requires polyamines for optimal intracellular growth.

    PubMed

    Nasrallah, Gheyath K; Riveroll, Angela L; Chong, Audrey; Murray, Lois E; Lewis, P Jeffrey; Garduño, Rafael A

    2011-09-01

    The Gram-negative intracellular pathogen Legionella pneumophila replicates in a membrane-bound compartment known as the Legionella-containing vacuole (LCV), into which it abundantly releases its chaperonin, HtpB. To determine whether HtpB remains within the LCV or reaches the host cell cytoplasm, we infected U937 human macrophages and CHO cells with L. pneumophila expressing a translocation reporter consisting of the Bordetella pertussisa denylate cyclase fused to HtpB. These infections led to increased cyclic AMP levels, suggesting that HtpB reaches the host cell cytoplasm. To identify potential functions of cytoplasmic HtpB, we expressed it in the yeast Saccharomyces cerevisiae, where HtpB induced pseudohyphal growth. A yeast-two-hybrid screen showed that HtpB interacted with S-adenosylmethionine decarboxylase (SAMDC), an essential yeast enzyme (encoded by SPE2) that is required for polyamine biosynthesis. Increasing the copy number of SPE2 induced pseudohyphal growth in S. cerevisiae; thus, we speculated that (i) HtpB induces pseudohyphal growth by activating polyamine synthesis and (ii) L. pneumophila may require exogenous polyamines for growth. A pharmacological inhibitor of SAMDC significantly reduced L. pneumophila replication in L929 mouse cells and U937 macrophages, whereas exogenously added polyamines moderately favored intracellular growth, confirming that polyamines and host SAMDC activity promote L. pneumophila proliferation. Bioinformatic analysis revealed that most known enzymes required for polyamine biosynthesis in bacteria (including SAMDC) are absent in L. pneumophila, further suggesting a need for exogenous polyamines. We hypothesize that HtpB may function to ensure a supply of polyamines in host cells, which are required for the optimal intracellular growth of L. pneumophila. PMID:21742865

  6. Cytogenetically aberrant cells in the stem cell compartment (CD34+lin-) in acute myeloid leukemia.

    PubMed

    Mehrotra, B; George, T I; Kavanau, K; Avet-Loiseau, H; Moore, D; Willman, C L; Slovak, M L; Atwater, S; Head, D R; Pallavicini, M G

    1995-08-01

    Leukemia may be viewed as a clonal expansion of blast cells; however, the role of primitive cells and/or stem cells in disease etiology and progression is unclear. We investigated stem cell involvement in leukemia using fluorescence in situ hybridization (FISH), immunofluorescence labeling of hematopoietic subpopulations, and flow cytometric analysis/sorting to discriminate and quantify cytogenetically aberrant stem cells in 12 acute myeloid leukemia (AML) and three myelodysplastic (MDS) specimens. Flow cytometric analysis and sorting were used to discriminate and collect a primitive subpopulation enriched in stem cells expressing CD34+ and lacking CD33 and CD38 (CD34+lin-). A subpopulation containing progenitors and differentiating myeloid cells expressed CD34, CD33, and CD38 (CD34+lin+). Nine specimens contained less than 10% CD34+ cells and, thus, were considered to be CD34- leukemias. Mature lymphoid, myeloid, and erythroid subpopulations were sorted on the basis of antigen-linked immunofluorescence. Cytogenetically aberrant cells in sorted subpopulations were identified using FISH with enumerator probes selected on the basis of diagnosis karyotype. Cytogenetically aberrant CD34+lin- cells were present at frequencies between 9% and 99% in all specimens. CD34+lin- cytogenetically aberrant cells comprised between 0.05% and 11.9% of the marrow/blood specimens. Cytogenetically aberrant CD34+lin+ cells constituted 0.01% tp 56% of the marrow/blood population. These data demonstrate that aberrant cells are present in primitive CD34+ stem cell compartments, even in CD34- leukemias. Stem cell involvement was confirmed further by sorting lymphoid and erythroid subpopulations from eight specimens in which the predominant leukemic population lacked lymphoid/erythroid differentiation markers. In these specimens, as well as in multiple lineages, suggests involvement of a cell(s) with multilineage capabilities. The ability of aberrant CD34+lin- stem cells to contribute to

  7. Intracellular targeting with engineered proteins.

    PubMed

    Miersch, Shane; Sidhu, Sachdev S

    2016-01-01

    If the isolation, production, and clinical use of insulin marked the inception of the age of biologics as therapeutics, the convergence of molecular biology and combinatorial engineering techniques marked its coming of age. The first wave of recombinant protein-based drugs in the 1980s demonstrated emphatically that proteins could be engineered, formulated, and employed for clinical advantage. Yet despite the successes of protein-based drugs such as antibodies, enzymes, and cytokines, the druggable target space for biologics is currently restricted to targets outside the cell. Insofar as estimates place the number of proteins either secreted or with extracellular domains in the range of 8000 to 9000, this represents only one-third of the proteome and circumscribes the pathways that can be targeted for therapeutic intervention. Clearly, a major objective for this field to reach maturity is to access, interrogate, and modulate the majority of proteins found inside the cell. However, owing to the large size, complex architecture, and general cellular impermeability of existing protein-based drugs, this poses a daunting challenge. In recent years, though, advances on the two related fronts of protein engineering and drug delivery are beginning to bring this goal within reach. First, prompted by the restrictions that limit the applicability of antibodies, intense efforts have been applied to identifying and engineering smaller alternative protein scaffolds for the modulation of intracellular targets. In parallel, innovative solutions for delivering proteins to the intracellular space while maintaining their stability and functional activity have begun to yield successes. This review provides an overview of bioactive intrabodies and alternative protein scaffolds amenable to engineering for intracellular targeting and also outlines advances in protein engineering and formulation for delivery of functional proteins to the interior of the cell to achieve therapeutic action.

  8. Intracellular targeting with engineered proteins

    PubMed Central

    Miersch, Shane; Sidhu, Sachdev S.

    2016-01-01

    If the isolation, production, and clinical use of insulin marked the inception of the age of biologics as therapeutics, the convergence of molecular biology and combinatorial engineering techniques marked its coming of age. The first wave of recombinant protein-based drugs in the 1980s demonstrated emphatically that proteins could be engineered, formulated, and employed for clinical advantage. Yet despite the successes of protein-based drugs such as antibodies, enzymes, and cytokines, the druggable target space for biologics is currently restricted to targets outside the cell. Insofar as estimates place the number of proteins either secreted or with extracellular domains in the range of 8000 to 9000, this represents only one-third of the proteome and circumscribes the pathways that can be targeted for therapeutic intervention. Clearly, a major objective for this field to reach maturity is to access, interrogate, and modulate the majority of proteins found inside the cell. However, owing to the large size, complex architecture, and general cellular impermeability of existing protein-based drugs, this poses a daunting challenge. In recent years, though, advances on the two related fronts of protein engineering and drug delivery are beginning to bring this goal within reach. First, prompted by the restrictions that limit the applicability of antibodies, intense efforts have been applied to identifying and engineering smaller alternative protein scaffolds for the modulation of intracellular targets. In parallel, innovative solutions for delivering proteins to the intracellular space while maintaining their stability and functional activity have begun to yield successes. This review provides an overview of bioactive intrabodies and alternative protein scaffolds amenable to engineering for intracellular targeting and also outlines advances in protein engineering and formulation for delivery of functional proteins to the interior of the cell to achieve therapeutic action

  9. Pharmacology of intracellular signalling pathways

    PubMed Central

    Nahorski, Stefan R

    2006-01-01

    This article provides a brief and somewhat personalized review of the dramatic developments that have occurred over the last 45 years in our understanding of intracellular signalling pathways associated with G-protein-coupled receptor activation. Signalling via cyclic AMP, the phosphoinositides and Ca2+ is emphasized and these systems have already been revealed as new pharmacological targets. The therapeutic benefits of most of such targets are, however, yet to be realized, but it is certain that the discipline of pharmacology needs to widen its boundaries to meet these challenges in the future. PMID:16402119

  10. Comparative efficacy of chloramphenicol loaded chondroitin sulfate and dextran sulfate nanoparticles to treat intracellular Salmonella infections.

    PubMed

    Kiruthika, V; Maya, S; Suresh, Maneesha K; Kumar, V Anil; Jayakumar, R; Biswas, Raja

    2015-03-01

    Salmonella Paratyphi A is a food-borne Gram-negative pathogen and a major public health challenge in the developing world. Upon reaching the intestine, S. Paratyphi A penetrates the intestinal epithelial barrier; and infects phagocytes such as macrophages and dendritic cells. S. Paratyphi A surviving within macrophages is protected from the lethal action of antibiotics due to their poor penetration into the intracellular compartments. Hence we have developed chloramphenicol loaded chondroitin sulfate (CS-Cm Nps) and dextran sulfate (DS-Cm Nps) nanoparticles through ionotropic-gelation method for the intracellular delivery of chloramphenicol. The size of these nanoparticles ranged between 100 and 200 nm in diameter. The encapsulation efficiency of both the nanoparticles was found to be around 65%. Both the nanoparticles are found to be non-hemolytic and non-toxic to fibroblast and epithelial cells. The prepared nanoparticles exhibited sustained release of the drug of up to 40% at pH 5 and 20-25% at pH 7.0 after 168 h. The anti-microbial activities of both nanoparticles were tested under in vitro and ex vivo conditions. The delivery of DS-Cm Nps into the intracellular compartments of the macrophages was 4 fold more compared to the CS-Cm Nps which lead to the enhanced intracellular antimicrobial activity of Ds-Cm Nps. Enhanced anti-microbial activity of Ds-Cm Nps was further confirmed in an ex vivo chicken intestine infection model. Our results showed that Cm loaded DS Nps can be used to treat intracellular Salmonella infections.

  11. Comparative efficacy of chloramphenicol loaded chondroitin sulfate and dextran sulfate nanoparticles to treat intracellular Salmonella infections.

    PubMed

    Kiruthika, V; Maya, S; Suresh, Maneesha K; Kumar, V Anil; Jayakumar, R; Biswas, Raja

    2015-03-01

    Salmonella Paratyphi A is a food-borne Gram-negative pathogen and a major public health challenge in the developing world. Upon reaching the intestine, S. Paratyphi A penetrates the intestinal epithelial barrier; and infects phagocytes such as macrophages and dendritic cells. S. Paratyphi A surviving within macrophages is protected from the lethal action of antibiotics due to their poor penetration into the intracellular compartments. Hence we have developed chloramphenicol loaded chondroitin sulfate (CS-Cm Nps) and dextran sulfate (DS-Cm Nps) nanoparticles through ionotropic-gelation method for the intracellular delivery of chloramphenicol. The size of these nanoparticles ranged between 100 and 200 nm in diameter. The encapsulation efficiency of both the nanoparticles was found to be around 65%. Both the nanoparticles are found to be non-hemolytic and non-toxic to fibroblast and epithelial cells. The prepared nanoparticles exhibited sustained release of the drug of up to 40% at pH 5 and 20-25% at pH 7.0 after 168 h. The anti-microbial activities of both nanoparticles were tested under in vitro and ex vivo conditions. The delivery of DS-Cm Nps into the intracellular compartments of the macrophages was 4 fold more compared to the CS-Cm Nps which lead to the enhanced intracellular antimicrobial activity of Ds-Cm Nps. Enhanced anti-microbial activity of Ds-Cm Nps was further confirmed in an ex vivo chicken intestine infection model. Our results showed that Cm loaded DS Nps can be used to treat intracellular Salmonella infections. PMID:25645750

  12. Small G proteins of two green algae are localized to exocytic compartments and to flagella.

    PubMed

    Huber, H; Beyser, K; Fabry, S

    1996-05-01

    The Ypt/Rab proteins are small GTPases, which belong to the Ras superfamily and have been shown to be involved in endo- and exocytosis in mammalian cells and yeast. Using affinity-purified antibodies specific for four Ypt proteins, namely Ypt1p, Ypt4p, Ypt5p and Ypt6p, of the multicellular green alga Volvox carteri (YptVp) and its close unicellular relative Chlamydomonas reinhardtii (YptCp), we examined the abundance of the corresponding antigens during the asexual life cycle of Volvox, and their intracellular localization. The YptV proteins were found in all stages throughout the asexual life cycle and are tightly associated with intracellular membranes. Indirect immunofluorescence revealed that YptV4p, YptV5p and YptV6p are present in perinuclear regions of the cell, indicating an association with the Golgi region. Golgi localization of YptV4p and YptV6p in Volvox was confirmed by immunogold electron microscopy. In contrast, we found Ypt1p associated with the contractile vacuole in both V. carteri and C. reinhardtii. Furthermore, the YptV proteins were also detected along the entire length of the flagella of somatic Volvox cells. This flagellar location was substantiated by western blot analysis of extracts prepared from isolated flagella of both algae. While localization to exocytic compartments is in agreement with the established Ypt/Rab function in intracellular vesicle transport of eukaryotic cells, presence in the algal flagellum is the first hint of a possible role for small G proteins also in motility organelles.

  13. Glycan modification of antigen alters its intracellular routing in dendritic cells, promoting priming of T cells

    PubMed Central

    Streng-Ouwehand, Ingeborg; Ho, Nataschja I; Litjens, Manja; Kalay, Hakan; Boks, Martine Annemarie; Cornelissen, Lenneke AM; Kaur Singh, Satwinder; Saeland, Eirikur; Garcia-Vallejo, Juan J; Ossendorp, Ferry A; Unger, Wendy WJ; van Kooyk, Yvette

    2016-01-01

    Antigen uptake by dendritic cells and intracellular routing of antigens to specific compartments is regulated by C-type lectin receptors that recognize glycan structures. We show that the modification of Ovalbumin (OVA) with the glycan-structure LewisX (LeX) re-directs OVA to the C-type lectin receptor MGL1. LeX-modification of OVA favored Th1 skewing of CD4+ T cells and enhanced cross-priming of CD8+ T cells. While cross-presentation of native OVA requires high antigen dose and TLR stimuli, LeX modification reduces the required amount 100-fold and obviates its dependence on TLR signaling. The OVA-LeX-induced enhancement of T cell cross-priming is MGL1-dependent as shown by reduced CD8+ effector T cell frequencies in MGL1-deficient mice. Moreover, MGL1-mediated cross-presentation of OVA-LeX neither required TAP-transporters nor Cathepsin-S and was still observed after prolonged intracellular storage of antigen in Rab11+LAMP1+ compartments. We conclude that controlled neo-glycosylation of antigens can crucially influence intracellular routing of antigens, the nature and strength of immune responses and should be considered for optimizing current vaccination strategies. DOI: http://dx.doi.org/10.7554/eLife.11765.001 PMID:26999763

  14. Telomere-surrounding regions are transcription-permissive 3D nuclear compartments in human cells

    SciTech Connect

    Quina, Ana Sofia; Parreira, Leonor . E-mail: lparreir@igc.gulbenkian.pt

    2005-07-01

    Positioning of genes relative to nuclear heterochromatic compartments is thought to help regulate their transcriptional activity. Given that human subtelomeric regions are rich in highly expressed genes, we asked whether human telomeres are related to transcription-permissive nuclear compartments. To address this question, we investigated in the nuclei of normal human lymphocytes the spatial relations of two constitutively expressed genes (ACTB and RARA) and three nuclear transcripts (ACTB, IL2RA and TCRB) to telomeres and centromeres, as a function of gene activity and transcription levels. We observed that genes and gene transcripts locate close to telomere clusters and away from chromocenters upon activation of transcription. These findings, together with the observation that SC35 domains, which are enriched in pre-mRNA processing factors, are in close proximity to telomeres, indicate that telomere-neighboring regions are permissive to gene expression in human cells. Therefore, the associations of telomeres observed in the interphase nucleus might contribute, as opposed to chromocenters, for the establishment of transcription-permissive 3D nuclear compartments.

  15. Isolated Chronic Exertional Compartment Syndrome of the Lateral Lower Leg

    PubMed Central

    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

  16. Role of H(+)-pyrophosphatase activity in the regulation of intracellular pH in a scuticociliate parasite of turbot: Physiological effects.

    PubMed

    Mallo, Natalia; Lamas, Jesús; de Felipe, Ana-Paula; Sueiro, Rosa-Ana; Fontenla, Francisco; Leiro, José-Manuel

    2016-10-01

    The scuticociliatosis is a very serious disease that affects the cultured turbot, and whose causal agent is the anphizoic and marine euryhaline ciliate Philasterides dicentrarchi. Several protozoans possess acidic organelles that contain high concentrations of pyrophosphate (PPi), Ca(2+) and other elements with essential roles in vesicular trafficking, pH homeostasis and osmoregulation. P. dicentrarchi possesses a pyrophosphatase (H(+)-PPase) that pumps H(+) through the membranes of vacuolar and alveolar sacs. These compartments share common features with the acidocalcisomes described in other parasitic protozoa (e.g. acid content and Ca(2+) storage). We evaluated the effects of Ca(2+) and ATP on H (+)-PPase activity in this ciliate and analyzed their role in maintaining intracellular pH homeostasis and osmoregulation, by the addition of PPi and inorganic molecules that affect osmolarity. Addition of PPi led to acidification of the intracellular compartments, while the addition of ATP, CaCl2 and bisphosphonates analogous of PPi and Ca(2+) metabolism regulators led to alkalinization and a decrease in H(+)-PPase expression in trophozoites. Addition of NaCl led to proton release, intracellular Ca(2+) accumulation and downregulation of H(+)-PPase expression. We conclude that the regulation of the acidification of intracellular compartments may be essential for maintaining the intracellular pH homeostasis necessary for survival of ciliates and their adaptation to salt stress, which they will presumably face during the endoparasitic phase, in which the salinity levels are lower than in their natural environment.

  17. Role of H(+)-pyrophosphatase activity in the regulation of intracellular pH in a scuticociliate parasite of turbot: Physiological effects.

    PubMed

    Mallo, Natalia; Lamas, Jesús; de Felipe, Ana-Paula; Sueiro, Rosa-Ana; Fontenla, Francisco; Leiro, José-Manuel

    2016-10-01

    The scuticociliatosis is a very serious disease that affects the cultured turbot, and whose causal agent is the anphizoic and marine euryhaline ciliate Philasterides dicentrarchi. Several protozoans possess acidic organelles that contain high concentrations of pyrophosphate (PPi), Ca(2+) and other elements with essential roles in vesicular trafficking, pH homeostasis and osmoregulation. P. dicentrarchi possesses a pyrophosphatase (H(+)-PPase) that pumps H(+) through the membranes of vacuolar and alveolar sacs. These compartments share common features with the acidocalcisomes described in other parasitic protozoa (e.g. acid content and Ca(2+) storage). We evaluated the effects of Ca(2+) and ATP on H (+)-PPase activity in this ciliate and analyzed their role in maintaining intracellular pH homeostasis and osmoregulation, by the addition of PPi and inorganic molecules that affect osmolarity. Addition of PPi led to acidification of the intracellular compartments, while the addition of ATP, CaCl2 and bisphosphonates analogous of PPi and Ca(2+) metabolism regulators led to alkalinization and a decrease in H(+)-PPase expression in trophozoites. Addition of NaCl led to proton release, intracellular Ca(2+) accumulation and downregulation of H(+)-PPase expression. We conclude that the regulation of the acidification of intracellular compartments may be essential for maintaining the intracellular pH homeostasis necessary for survival of ciliates and their adaptation to salt stress, which they will presumably face during the endoparasitic phase, in which the salinity levels are lower than in their natural environment. PMID:27480055

  18. Intracellular Phosphate Dynamics in Muscle Measured by Magnetic Resonance Spectroscopy during Hemodialysis.

    PubMed

    Lemoine, Sandrine; Fournier, Thomas; Kocevar, Gabriel; Belloi, Amélie; Normand, Gabrielle; Ibarrola, Danielle; Sappey-Marinier, Dominique; Juillard, Laurent

    2016-07-01

    Of the 600-700 mg inorganic phosphate (Pi) removed during a 4-hour hemodialysis session, a maximum of 10% may be extracted from the extracellular space. The origin of the other 90% of removed phosphate is unknown. This study tested the hypothesis that the main source of phosphate removed during hemodialysis is the intracellular compartment. Six binephrectomized pigs each underwent one 3-hour hemodialysis session, during which the extracorporeal circulation blood flow was maintained between 100 and 150 ml/min. To determine in vivo phosphate metabolism, we performed phosphorous ((31)P) magnetic resonance spectroscopy using a 1.5-Tesla system and a surface coil placed over the gluteal muscle region. (31)P magnetic resonance spectra (repetition time =10 s; echo time =0.35 ms) were acquired every 160 seconds before, during, and after dialysis. During the dialysis sessions, plasma phosphate concentrations decreased rapidly (-30.4 %; P=0.003) and then, plateaued before increasing approximately 30 minutes before the end of the sessions; 16 mmol phosphate was removed in each session. When extracellular phosphate levels plateaued, intracellular Pi content increased significantly (11%; P<0.001). Moreover, βATP decreased significantly (P<0.001); however, calcium levels remained balanced. Results of this study show that intracellular Pi is the source of Pi removed during dialysis. The intracellular Pi increase may reflect cellular stress induced by hemodialysis and/or strong intracellular phosphate regulation. PMID:26561642

  19. Intracellular trafficking of nucleic acids.

    PubMed

    Zhou, Rui; Geiger, R Christopher; Dean, David A

    2004-11-01

    Until recently, the attention of most researchers has focused on the first and last steps of gene transfer, namely delivery to the cell and transcription, in order to optimise transfection and gene therapy. However, over the past few years, researchers have realised that the intracellular trafficking of plasmids is more than just a "black box" and is actually one of the major barriers to effective gene delivery. After entering the cytoplasm, following direct delivery or endocytosis, plasmids or other vectors must travel relatively long distances through the mesh of cytoskeletal networks before reaching the nuclear envelope. Once at the nuclear envelope, the DNA must either wait until cell division, or be specifically transported through the nuclear pore complex, in order to reach the nucleoplasm where it can be transcribed. This review focuses on recent developments in the understanding of these intracellular trafficking events as they relate to gene delivery. Hopefully, by continuing to unravel the mechanisms by which plasmids and other gene delivery vectors move throughout the cell, and by understanding the cell biology of gene transfer, superior methods of transfection and gene therapy can be developed.

  20. Placental Hofbauer cells assemble and sequester HIV-1 in tetraspanin-positive compartments that are accessible to broadly neutralizing antibodies

    PubMed Central

    Johnson, Erica L; Chu, Hin; Byrareddy, Siddappa Nagadenahalli; Spearman, Paul; Chakraborty, Rana

    2015-01-01

    Introduction Within monocyte-derived macrophages, HIV-1 accumulates in intracellular virus-containing compartments (VCCs) that are inaccessible to the external environment, which implicate these cells as latently infected HIV-1 reservoirs. During mother-to-child transmission of HIV-1, human placental macrophages (Hofbauer cells (HCs)) are viral targets, and have been shown to be infected in vivo and sustain low levels of viral replication in vitro; however, the risk of in utero transmission is less than 7%. The role of these primary macrophages as viral reservoirs is largely undefined. The objective of this study is to define potential sites of viral assembly, accumulation and neutralization in HCs given the pivotal role of the placenta in preventing HIV-1 infection in the mother-infant dyad. Methods Term placentae from 20 HIV-1 seronegative women were obtained following caesarian section. VCCs were evaluated by 3D confocal and electron microscopy. Colocalization R values (Pearson's correlation) were quantified with colocalization module of Volocity 5.2.1. Replication kinetics and neutralization studies were evaluated using p24 ELISA. Results We demonstrate that primary HCs assemble and sequester HIV-1BaL in intracellular VCCs, which are enriched in endosomal/lysosomal markers, including CD9, CD81, CD63 and LAMP-1. Following infection, we observed HIV-1 accumulation in potentially acidic compartments, which stained intensely with Lysotracker-Red. Remarkably, these compartments are readily accessible via the cell surface and can be targeted by exogenously applied small molecules and HIV-1-specific broadly neutralizing antibodies. In addition, broadly neutralizing antibodies (4E10 and VRC01) limited viral replication by HIV-1-infected HCs, which may be mediated by FcγRI. Conclusions These findings suggest that placental HCs possess intrinsic adaptations facilitating unique sequestration of HIV-1, and may serve as a protective viral reservoir to permit viral

  1. Matrix metalloproteinase-9 expression in the nuclear compartment of neurons and glial cells in aging and stroke.

    PubMed

    Pirici, Daniel; Pirici, Ionica; Mogoanta, Laurentiu; Margaritescu, Otilia; Tudorica, Valerica; Margaritescu, Claudiu; Ion, Daniela A; Simionescu, Cristiana; Coconu, Marieta

    2012-10-01

    Matrix metalloproteinases (MMPs) are well-recognized denominators for extracellular matrix remodeling in the pathology of both ischemic and hemorrhagic strokes. Recent data on non-nervous system tissue showed intracellular and even intranuclear localizations for different MMPs, and together with this, a plethora of new functions have been proposed for these intracellular active enzymes, but are mostly related to apoptosis induction and malign transformation. In neurons and glial cells, on human tissue, animal models and cell cultures, different active MMPs have been also proven to be located in the intra-cytoplasmic or intra-nuclear compartments, with no clear-cut function. In the present study we show for the first time on human tissue the nuclear expression of MMP-9, mainly in neurons and to a lesser extent in astrocytes. We have studied ischemic and hemorrhagic stroke patients, as well as aged control patients. Age and ischemic suffering seemed to be the best predictors for an elevated MMP-9 nuclear expression, and there was no evidence of a clear-cut extracellular proteolytic activity for this compartment, as revealed by intact vascular basement membranes and assessment of vascular densities. More, the majority of the cells expressing MMP-9 in the nuclear compartment also co-expressed activated-caspase 3, indicating a possible link between nuclear MMP-9 localization and apoptosis in neuronal and glial cells following an ischemic or hemorrhagic event. These results, besides showing for the first time the nuclear localization of MMP-9 on a large series of human stroke and aged brain tissues, raise new questions regarding the unknown spectrum of the functions MMPs in human CNS pathology.

  2. NSort/DB: an intranuclear compartment protein database.

    PubMed

    Willadsen, Kai; Mohamad, Nurul; Bodén, Mikael

    2012-08-01

    Distinct substructures within the nucleus are associated with a wide variety of important nuclear processes. Structures such as chromatin and nuclear pores have specific roles, while others such as Cajal bodies are more functionally varied. Understanding the roles of these membraneless intra-nuclear compartments requires extensive data sets covering nuclear and compartment-associated proteins. NSort/DB is a database providing access to intra- or sub-nuclear compartment associations for the mouse nuclear proteome. Based on resources ranging from large-scale curated data sets to detailed experiments, this data set provides a high-quality set of annotations of non-exclusive association of nuclear proteins with structures such as promyelocytic leukaemia bodies and chromatin. The database is searchable by protein identifier or compartment, and has a documented web service API. The search interface, web service and data download are all freely available online at http://www.nsort.org/db/. Availability of this data set will enable systematic analyses of the protein complements of nuclear compartments, improving our understanding of the diverse functional repertoire of these structures.

  3. Numerical modelling of crural fascia mechanical interaction with muscular compartments.

    PubMed

    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.

  4. Bilaterally Symmetrical Lower Extremity Compartment Syndrome following Massive Transfusion

    PubMed Central

    Karaoren, Gulsah; Bakan, Nurten; Tomruk, Senay Goksu; Topaç, Zelin; Kurtulmuş, Tuhan; Irkören, Saime

    2016-01-01

    Compartment syndrome is a serious condition characterized by raised intracompartmental pressure, which develops following trauma. Well leg compartment syndrome (WLCS) is a term reserved for compartment syndrome in a nontraumatic setting, usually resulting from prolonged lithotomy position during surgery. In literature, 8 cases have been reported regarding well leg compartment syndrome in a supine position and bilateral symmetrical involvement was observed in only 2 cases. In WLCS etiology, lengthy surgery, lengthy hypotension, and extremity malpositioning have been held responsible but one of the factors with a role in the etiology may have been the tissue oedema and impaired microcirculation formed from the effect of vasoactive mediators expressed into the circulation associated with the massive blood transfusion. The case is presented here regarding symmetrical lower extremity compartment syndrome after surgery in which massive transfusion was made for gross haemorrhage from an abdominal injury. In conclusion, blood transfusion applied at the required time is life-saving but potential risks must always be considered. PMID:26885421

  5. The Posttranslocation Chaperone PrsA2 Contributes to Multiple Facets of Listeria monocytogenes Pathogenesis▿ †

    PubMed Central

    Alonzo, Francis; Port, Gary C.; Cao, Min; Freitag, Nancy E.

    2009-01-01

    Listeria monocytogenes is an intracellular bacterial pathogen whose virulence depends on the regulated expression of numerous secreted bacterial factors. As for other gram-positive bacteria, many proteins secreted by L. monocytogenes are translocated across the bacterial membrane in an unfolded state to the compartment existing between the membrane and the cell wall. This compartment presents a challenging environment for protein folding due to its high density of negative charge, high concentrations of cations, and low pH. We recently identified PrsA2 as a gene product required for L. monocytogenes virulence. PrsA2 was identified based on its increased secretion by strains containing a mutationally activated form of prfA, the key regulator of L. monocytogenes virulence gene expression. The prsA2 gene product is one of at least two predicted peptidyl-prolyl cis/trans-isomerases encoded by L. monocytogenes; these proteins function as posttranslocation protein chaperones and/or foldases. In this study, we demonstrate that PrsA2 plays a unique and important role in L. monocytogenes pathogenesis by promoting the activity and stability of at least two critical secreted virulence factors: listeriolysin O (LLO) and a broad-specificity phospholipase. Loss of PrsA2 activity severely attenuated virulence in mice and impaired bacterial cell-to-cell spread in host cells. In contrast, mutants lacking prsA1 resembled wild-type bacteria with respect to intracellular growth and cell-to-cell spread as well as virulence in mice. PrsA2 is thus distinct from PrsA1 in its unique requirement for the stability and full activity of L. monocytogenes-secreted factors that contribute to host infection. PMID:19451247

  6. Acute compartment syndrome of the foot in a 17-year-old boy.

    PubMed

    Salvi, Andrea Emilio; Roda, Simone; Florschutz, Anthony Vatroslav

    2012-01-01

    Acute compartment syndrome is both a life and limb threatening surgical emergency, caused by an increase in compartment contents due to either trauma or surgery. We illustrate a foot compartment syndrome, clinically diagnosed, that took place after direct injury during a football match. Compartments release through fasciotomies promptly relieved symptoms. Educational images are furnished.

  7. Intracellular Streptococcus pyogenes in Human Macrophages Display an Altered Gene Expression Profile

    PubMed Central

    Hertzén, Erika; Johansson, Linda; Kansal, Rita; Hecht, Alexander; Dahesh, Samira; Janos, Marton; Nizet, Victor; Kotb, Malak; Norrby-Teglund, Anna

    2012-01-01

    Streptococcus pyogenes is an important human pathogen, which has recently gained recognition as an intracellular microorganism during the course of severe invasive infections such as necrotizing fasciitis. Although the surface anchored M protein has been identified as a pivotal factor affecting phagosomal maturation and S. pyogenes survival within macrophages, the overall transcriptional profile required for the pathogen to adapt and persist intracellularly is as of yet unknown. To address this, the gene expression profile of S. pyogenes within human macrophages was determined and compared to that of extracellular bacteria using customized microarrays and real-time qRT-PCR. In order to model the early phase of infection involving adaptation to the intracellular compartment, samples were collected 2h post-infection. Microarray analysis revealed that the expression of 145 streptococcal genes was significantly altered in the intracellular environment. The majority of differentially regulated genes were associated with metabolic and energy-dependent processes. Key up-regulated genes in early phase intracellular bacteria were ihk and irr, encoding a two-component gene regulatory system (TCS). Comparison of gene expression of selected genes at 2h and 6h post-infection revealed a dramatic shift in response regulators over time with a down-regulation of ihk/irr genes concurring with an up-regulation of the covR/S TCS. In re-infection assays, intracellular bacteria from the 6h time point exhibited significantly greater survival within macrophages than did bacteria collected at the 2h time point. An isogenic S. pyogenes mutant deficient in ihk/irr displayed significantly reduced bacterial counts when compared to wild-type bacteria following infection of macrophages. The findings illustrate how gene expression of S. pyogenes during the intracellular life cycle is fine-tuned by temporal expression of specific two-component systems. PMID:22511985

  8. Intracellular Streptococcus pyogenes in human macrophages display an altered gene expression profile.

    PubMed

    Hertzén, Erika; Johansson, Linda; Kansal, Rita; Hecht, Alexander; Dahesh, Samira; Janos, Marton; Nizet, Victor; Kotb, Malak; Norrby-Teglund, Anna

    2012-01-01

    Streptococcus pyogenes is an important human pathogen, which has recently gained recognition as an intracellular microorganism during the course of severe invasive infections such as necrotizing fasciitis. Although the surface anchored M protein has been identified as a pivotal factor affecting phagosomal maturation and S. pyogenes survival within macrophages, the overall transcriptional profile required for the pathogen to adapt and persist intracellularly is as of yet unknown. To address this, the gene expression profile of S. pyogenes within human macrophages was determined and compared to that of extracellular bacteria using customized microarrays and real-time qRT-PCR. In order to model the early phase of infection involving adaptation to the intracellular compartment, samples were collected 2h post-infection. Microarray analysis revealed that the expression of 145 streptococcal genes was significantly altered in the intracellular environment. The majority of differentially regulated genes were associated with metabolic and energy-dependent processes. Key up-regulated genes in early phase intracellular bacteria were ihk and irr, encoding a two-component gene regulatory system (TCS). Comparison of gene expression of selected genes at 2h and 6h post-infection revealed a dramatic shift in response regulators over time with a down-regulation of ihk/irr genes concurring with an up-regulation of the covR/S TCS. In re-infection assays, intracellular bacteria from the 6h time point exhibited significantly greater survival within macrophages than did bacteria collected at the 2h time point. An isogenic S. pyogenes mutant deficient in ihk/irr displayed significantly reduced bacterial counts when compared to wild-type bacteria following infection of macrophages. The findings illustrate how gene expression of S. pyogenes during the intracellular life cycle is fine-tuned by temporal expression of specific two-component systems.

  9. Role of host cell-derived amino acids in nutrition of intracellular Salmonella enterica.

    PubMed

    Popp, Jasmin; Noster, Janina; Busch, Kim; Kehl, Alexander; Zur Hellen, Gero; Hensel, Michael

    2015-12-01

    The facultative intracellular pathogen Salmonella enterica resides in a specific membrane-bound compartment termed the Salmonella-containing vacuole (SCV). Despite being segregated from access to metabolites in the host cell cytosol, Salmonella is able to efficiently proliferate within the SCV. We set out to unravel the nutritional supply of Salmonella in the SCV with focus on amino acids. We studied the availability of amino acids by the generation of auxotrophic strains for alanine, asparagine, aspartate, glutamine, and proline in a macrophage cell line (RAW264.7) and an epithelial cell line (HeLa) and examined access to extracellular nutrients for nutrition. Auxotrophies for alanine, asparagine, or proline attenuated intracellular replication in HeLa cells, while aspartate, asparagine, or proline auxotrophies attenuated intracellular replication in RAW264.7 macrophages. The different patterns of intracellular attenuation of alanine- or aspartate-auxotrophic strains support distinct nutritional conditions in HeLa cells and RAW264.7 macrophages. Supplementation of medium with individual amino acids restored the intracellular replication of mutant strains auxotrophic for asparagine, proline, or glutamine. Similarly, a mutant strain deficient in succinate dehydrogenase was complemented by the extracellular addition of succinate. Complementation of the intracellular replication of auxotrophic Salmonella by external amino acids was possible if bacteria were proficient in the induction of Salmonella-induced filaments (SIFs) but failed in a SIF-deficient background. We propose that the ability of intracellular Salmonella to redirect host cell vesicular transport provides access of amino acids to auxotrophic strains and, more generally, is essential to continuously supply bacteria within the SCV with nutrients.

  10. On the origin of genomes and cells within inorganic compartments.

    PubMed

    Koonin, Eugene V; Martin, William

    2005-12-01

    Building on the model of Russell and Hall for the emergence of life at a warm submarine hydrothermal vent, we suggest that, within a hydrothermally formed system of contiguous iron-sulfide (FeS) compartments, populations of virus-like RNA molecules, which eventually encoded one or a few proteins each, became the agents of both variation and selection. The initial darwinian selection was for molecular self-replication. Combinatorial sorting of genetic elements among compartments would have resulted in preferred proliferation and selection of increasingly complex molecular ensembles--those compartment contents that achieved replication advantages. The last universal common ancestor (LUCA) we propose was not free-living but an inorganically housed assemblage of expressed and replicable genetic elements. The evolution of the enzymatic systems for (i) DNA replication; and (ii) membrane and cell wall biosynthesis, enabled independent escape of the first archaebacterial and eubacterial cells from their hydrothermal hatchery, within which the LUCA itself remained confined. PMID:16223546

  11. Psittacine paranasal sinus--a new definition of compartments.

    PubMed

    Artmann, A; Henninger, W

    2001-12-01

    Documentation of the psittacine paranasal sinuses has been limited. To provide more published detail, spiral computed tomography (CT) was used to scan the cephalic and cervical region from cadavers of 10 psittacine birds (Ara ararauna, Ara chloroptera, Ara macao, and Anodorhynchus hyacinthinus). Skeletal studies, histologic examinations, and evaluation of deep-frozen sections and anatomic preparations confirmed the results of the CT scans. New morphologic details of the paranasal sinus and some compartments were discovered. The paranasal sinuses of these macaws consist of two unpaired rostral compartments, followed caudally by eight paired compartments. Histologic examinations revealed that the walls of the paranasal sinuses consist of flat or cubic monolayer epithelium with underlying connective tissue. The described method of CT examination of these macaws, especially the positioning, scan orientation and parameters, and documentation of the normal paranasal sinus, provides a basis for future clinical use of CT.

  12. Fire safety evaluation of aircraft lavatory and cargo compartments

    NASA Technical Reports Server (NTRS)

    Kourtides, D. A.; Parker, J. A.; Hilado, C. J.; Anderson, R. A.; Tustin, E.; Arnold, D. E.; Gaume, J. G.; Binding, A. T.; Mikeska, J. L.

    1975-01-01

    Large-scale aircraft lavatory and cargo compartment fire tests are described. Tests were conducted to evaluate the effectiveness of these compartments to contain fire and smoke. Two tests were conducted and are detailed. Test 1 involved a production Boeing 747 lavatory of the latest design installed in an enclosure outside the aircraft, to collect gases and expose animals to these gases. Results indicate that the interior of the lavatory was completely burned, evolving smoke and combustion products in the enclosure. Test 2 involved a simulated Douglas DC-10 cargo compartment retro-fitted with standard fiberglass liner. The fire caused excessive damage to the liner and burned through the ceiling in two areas. Test objectives, methods, materials, and results are presented and discussed.

  13. Coats, tethers, Rabs, and SNAREs work together to mediate the intracellular destination of a transport vesicle.

    PubMed

    Cai, Huaqing; Reinisch, Karin; Ferro-Novick, Susan

    2007-05-01

    Tethering factors have been shown to interact with Rabs and SNAREs and, more recently, with coat proteins. Coat proteins are required for cargo selection and membrane deformation to bud a transport vesicle from a donor compartment. It was once thought that a vesicle must uncoat before it recognizes its target membrane. However, recent findings have revealed a role for the coat in directing a vesicle to its correct intracellular destination. In this review we will discuss the literature that links coat proteins to vesicle targeting events. PMID:17488620

  14. The emerging role of phosphoinositide clustering in intracellular trafficking and signal transduction

    PubMed Central

    Picas, Laura; Gaits-Iacovoni, Frederique; Goud, Bruno

    2016-01-01

    Phosphoinositides are master regulators of multiple cellular processes: from vesicular trafficking to signaling, cytoskeleton dynamics, and cell growth. They are synthesized by the spatiotemporal regulated activity of phosphoinositide-metabolizing enzymes. The recent observation that some protein modules are able to cluster phosphoinositides suggests that alternative or complementary mechanisms might operate to stabilize the different phosphoinositide pools within cellular compartments. Herein, we discuss the different known and potential molecular players that are prone to engage phosphoinositide clustering and elaborate on how such a mechanism might take part in the regulation of intracellular trafficking and signal transduction. PMID:27092250

  15. Primary Cilia and Dendritic Spines: Different but Similar Signaling Compartments

    PubMed Central

    Nechipurenko, Inna V.; Doroquez, David B.; Sengupta, Piali

    2013-01-01

    Primary non-motile cilia and dendritic spines are cellular compartments that are specialized to sense and transduce environmental cues and presynaptic signals, respectively. Despite their unique cellular roles, both compartments exhibit remarkable parallels in the general principles, as well as molecular mechanisms, by which their protein composition, membrane domain architecture, cellular interactions, and structural and functional plasticity are regulated. We compare and contrast the pathways required for the generation and function of cilia and dendritic spines, and suggest that insights from the study of one may inform investigations into the other of these critically important signaling structures. PMID:24048681

  16. Acute compartment syndrome of the thigh in a rugby player.

    PubMed

    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.

  17. Type VI Secretion System-Associated Gene Clusters Contribute to Pathogenesis of Salmonella enterica Serovar Typhimurium

    PubMed Central

    Mulder, David T.; Cooper, Colin A.

    2012-01-01

    The enteropathogen Salmonella enterica serovar Typhimurium employs a suite of tightly regulated virulence factors within the intracellular compartment of phagocytic host cells resulting in systemic dissemination in mice. A type VI secretion system (T6SS) within Salmonella pathogenicity island 6 (SPI-6) has been implicated in this process; however, the regulatory inputs and the roles of noncore genes in this system are not well understood. Here we describe four clusters of noncore T6SS genes in SPI-6 based on a comparative relationship with the T6SS-3 of Burkholderia mallei and report that the disruption of these genes results in defects in intracellular replication and systemic dissemination in mice. In addition, we show that the expression of the SPI-6-encoded Hcp and VgrG orthologs is enhanced during late stages of macrophage infection. We identify six regions that are transcriptionally active during cell infections and that have regulatory contributions from the regulators of virulence SsrB, PhoP, and SlyA. We show that levels of protein expression are very weak under in vitro conditions and that expression is not enhanced upon the deletion of ssrB, phoP, slyA, qseC, ompR, or hfq, suggesting an unknown activating factor. These data suggest that the SPI-6 T6SS has been integrated into the Salmonella Typhimurium virulence network and customized for host-pathogen interactions through the action of noncore genes. PMID:22493086

  18. An intracellular replication niche for Vibrio cholerae in the amoeba Acanthamoeba castellanii.

    PubMed

    Van der Henst, Charles; Scrignari, Tiziana; Maclachlan, Catherine; Blokesch, Melanie

    2016-04-01

    Vibrio cholerae is a human pathogen and the causative agent of cholera. The persistence of this bacterium in aquatic environments is a key epidemiological concern, as cholera is transmitted through contaminated water. Predatory protists, such as amoebae, are major regulators of bacterial populations in such environments. Therefore, we investigated the interaction between V. cholerae and the amoeba Acanthamoeba castellanii at the single-cell level. We observed that V. cholerae can resist intracellular killing. The non-digested bacteria were either released or, alternatively, established a replication niche within the contractile vacuole of A. castellanii. V. cholerae was maintained within this compartment even upon encystment. The pathogen ultimately returned to its aquatic habitat through lysis of A. castellanii, a process that was dependent on the production of extracellular polysaccharide by the pathogen. This study reinforces the concept that V. cholerae is a facultative intracellular bacterium and describes a new host-pathogen interaction.

  19. An intracellular replication niche for Vibrio cholerae in the amoeba Acanthamoeba castellanii

    PubMed Central

    Van der Henst, Charles; Scrignari, Tiziana; Maclachlan, Catherine; Blokesch, Melanie

    2016-01-01

    Vibrio cholerae is a human pathogen and the causative agent of cholera. The persistence of this bacterium in aquatic environments is a key epidemiological concern, as cholera is transmitted through contaminated water. Predatory protists, such as amoebae, are major regulators of bacterial populations in such environments. Therefore, we investigated the interaction between V. cholerae and the amoeba Acanthamoeba castellanii at the single-cell level. We observed that V. cholerae can resist intracellular killing. The non-digested bacteria were either released or, alternatively, established a replication niche within the contractile vacuole of A. castellanii. V. cholerae was maintained within this compartment even upon encystment. The pathogen ultimately returned to its aquatic habitat through lysis of A. castellanii, a process that was dependent on the production of extracellular polysaccharide by the pathogen. This study reinforces the concept that V. cholerae is a facultative intracellular bacterium and describes a new host–pathogen interaction. PMID:26394005

  20. Intracellular temperature mapping with a fluorescent polymeric thermometer and fluorescence lifetime imaging microscopy.

    PubMed

    Okabe, Kohki; Inada, Noriko; Gota, Chie; Harada, Yoshie; Funatsu, Takashi; Uchiyama, Seiichi

    2012-02-28

    Cellular functions are fundamentally regulated by intracellular temperature, which influences biochemical reactions inside a cell. Despite the important contributions to biological and medical applications that it would offer, intracellular temperature mapping has not been achieved. Here we demonstrate the first intracellular temperature mapping based on a fluorescent polymeric thermometer and fluorescence lifetime imaging microscopy. The spatial and temperature resolutions of our thermometry were at the diffraction limited level (200 nm) and 0.18-0.58 °C. The intracellular temperature distribution we observed indicated that the nucleus and centrosome of a COS7 cell, both showed a significantly higher temperature than the cytoplasm and that the temperature gap between the nucleus and the cytoplasm differed depending on the cell cycle. The heat production from mitochondria was also observed as a proximal local temperature increase. These results showed that our new intracellular thermometry could determine an intrinsic relationship between the temperature and organelle function.

  1. Intracellular temperature mapping with a fluorescent polymeric thermometer and fluorescence lifetime imaging microscopy

    PubMed Central

    Okabe, Kohki; Inada, Noriko; Gota, Chie; Harada, Yoshie; Funatsu, Takashi; Uchiyama, Seiichi

    2012-01-01

    Cellular functions are fundamentally regulated by intracellular temperature, which influences biochemical reactions inside a cell. Despite the important contributions to biological and medical applications that it would offer, intracellular temperature mapping has not been achieved. Here we demonstrate the first intracellular temperature mapping based on a fluorescent polymeric thermometer and fluorescence lifetime imaging microscopy. The spatial and temperature resolutions of our thermometry were at the diffraction limited level (200 nm) and 0.18–0.58 °C. The intracellular temperature distribution we observed indicated that the nucleus and centrosome of a COS7 cell, both showed a significantly higher temperature than the cytoplasm and that the temperature gap between the nucleus and the cytoplasm differed depending on the cell cycle. The heat production from mitochondria was also observed as a proximal local temperature increase. These results showed that our new intracellular thermometry could determine an intrinsic relationship between the temperature and organelle function. PMID:22426226

  2. Curcumin Mitigates the Intracellular Lipid Deposit Induced by Antipsychotics In Vitro

    PubMed Central

    Canfrán-Duque, Alberto; Pastor, Oscar; Reina, Manuel; Lerma, Milagros; Cruz-Jentoft, Alfonso J.

    2015-01-01

    Scope First- and second-generation antipsychotics (FGAs and SGAs, respectively), both inhibit cholesterol biosynthesis and impair the intracellular cholesterol trafficking, leading to lipid accumulation in the late endosome/lysosome compartment. In this study we examined if curcumin, a plant polyphenol that stimulates exosome release, can alleviate antipsychotic-induced intracellular lipid accumulation. Methods HepG2 hepatocarcinoma cells were treated with antipsychotics or placebo and DiI-labelled LDL for 18 h and then exposed to curcumin for the last 2 h. Cells and media were collected separately and used for biochemical analyses, electron microscopy and immunocytochemistry. Exosomes were isolated from the incubation medium by ultracentrifugation. Results Curcumin treatment reduced the number of heterolysosomes and shifted their subcellular localization to the periphery, as revealed by electron microscopy, and stimulated the release of lysosomal β-hexosaminidase and exosome markers flotillin-2 and CD63 into the media. The presence of DiI in exosomes released by cells preloaded with DiI-LDL demonstrated the endolysosomal origin of the microvesicles. Furthermore, curcumin increased the secretion of cholesterol as well as LDL-derived DiI and [3H]-cholesterol, in association with a decrease of intracellular lipids. Thus, the disruption of lipid trafficking induced by FGAs or SGAs can be relieved by curcumin treatment. This polyphenol, however, did not mitigate the reduction of cholesterol esterification induced by antipsychotics. Conclusion Curcumin stimulates exosome release to remove cholesterol (and presumably other lipids) accumulated within the endolysosomal compartment, thereby normalizing intracellular lipid homeostasis. This action may help minimize the adverse metabolic effects of antipsychotic treatment, which should now be evaluated in clinical trials. PMID:26517556

  3. Regulating Intracellular Calcium in Plants: From Molecular Genetics to Physiology

    SciTech Connect

    Heven Sze

    2008-06-22

    To grow, develop, adapt, and reproduce, plants have evolved mechanisms to regulate the uptake, translocation and sorting of calcium ions into different cells and subcellular compartments. Yet how plants accomplish this remarkable feat is still poorly understood. The spatial and temporal changes in intracellular [Ca2+] during growth and during responses to hormonal and environmental stimuli indicate that Ca2+ influx and efflux transporters are diverse and tightly regulated in plants. The specific goals were to determine the biological roles of multiple Ca pumps (ECAs) in the model plant Arabidopsis thaliana. We had pioneered the use of K616 yeast strain to functionally express plant Ca pumps, and demonstrated two distinct types of Ca pumps in plants (Sze et al., 2000. Annu Rev Plant Biol. 51,433). ACA2 represented one type that was auto-inhibited by the N-terminal region and stimulated by calmodulin. ECA1 represented another type that was not sensitive to calmodulin and phylogenetically distinct from ACAs. The goal to determine the biological roles of multiple ECA-type Ca pumps in Arabidopsis has been accomplished. Although we demonstrated ECA1 was a Ca pump by functional expression in yeast, the in vivo roles of ECAs was unclear. A few highlights are described. ECA1 and/or ECA4 are Ca/Mn pumps localized to the ER and are highly expressed in all cell types. Using homozygous T-DNA insertional mutants of eca1, we demonstrated that the ER-bound ECA1 supports growth and confers tolerance of plants growing on medium low in Ca or containing toxic levels of Mn. This is the first genetic study to determine the in vivo function of a Ca pump in plants. A phylogenetically distinct ECA3 is also a Ca/Mn pump that is localized to endosome, such as post-Golgi compartments. Although it is expressed at lower levels than ECA1, eca3 mutants are impaired in Ca-dependent root growth and in pollen tube elongation. Increased secretion of wall proteins in mutants suggests that Ca and Mn

  4. 9 CFR 354.221 - Rooms and compartments.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Rooms and compartments. 354.221 Section 354.221 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... rabbits are prepared, processed, handled, and stored. (g) Inspector's office. Furnished office...

  5. 9 CFR 354.221 - Rooms and compartments.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Rooms and compartments. 354.221 Section 354.221 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... rabbits are prepared, processed, handled, and stored. (g) Inspector's office. Furnished office...

  6. 14 CFR 27.787 - Cargo and baggage compartments.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Cargo and baggage compartments. 27.787 Section 27.787 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Personnel and Cargo Accommodations § 27.787 Cargo and...

  7. 14 CFR 29.787 - Cargo and baggage compartments.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Cargo and baggage compartments. 29.787 Section 29.787 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Personnel and Cargo Accommodations § 29.787 Cargo and...

  8. Regulating mechanical tension at compartment boundaries in Drosophila

    PubMed Central

    Michel, Marcus; Dahmann, Christian

    2016-01-01

    ABSTRACT During animal development, cells with similar function and fate often stay together and sort out from cells with different fates. In Drosophila wing imaginal discs, cells of anterior and posterior fates are separated by a straight compartment boundary. Separation of anterior and posterior cells requires the homeodomain-containing protein Engrailed, which is expressed in posterior cells. Engrailed induces the expression of the short-range signaling molecule Hedgehog in posterior cells and confines Hedgehog signal transduction to anterior cells. Transduction of the Hedgehog signal in anterior cells is required for the separation of anterior and posterior cells. Previous work showed that this separation of cells involves a local increase in mechanical tension at cell junctions along the compartment boundary. However, how mechanical tension was locally increased along the compartment boundary remained unknown. A recent paper now shows that the difference in Hedgehog signal transduction between anterior and posterior cells is necessary and sufficient to increase mechanical tension. The local increase in mechanical tension biases junctional rearrangements during cell intercalations to maintain the straight shape of the compartment boundary. These data highlight how developmental signals can generate patterns of mechanical tension important for tissue organization. PMID:27362651

  9. 12. Interior view of battle staff compartment showing the general's ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. Interior view of battle staff compartment showing the general's chair. View toward front of aircraft. - Offutt Air Force Base, Looking Glass Airborne Command Post, Looking Glass Aircraft, On Operational Apron covering northeast half of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  10. Gluteal compartment syndrome after prostatectomy caused by incorrect positioning.

    PubMed

    Heyn, Jens; Ladurner, R; Ozimek, A; Vogel, T; Hallfeldt, K K; Mussack, T

    2006-04-28

    Gluteal compartment syndrome is an uncommon and rare disease. Most reasonable causes for the development of this disease are trauma, drug induced coma, Ehlers-Danlos syndrome, sickle cell associated muscle infarction, incorrect positioning during surgical procedures and prolonged pressure in patients with altered consciousness levels. The diagnosis requires a high index of suspicion, especially in postoperative patient where sedation or peridural anaesthesia can confound the neurological examination. Early signs include gluteal tenderness, decrease in vibratory sensation during clinical examination and increasing CK in laboratory findings. We present a case of a 52 year-old patient, who developed gluteal compartment syndrome after radical prostatectomy in lithotomic position. After operation, diuresis decreased [<50 ml/h] and CK [93927 U/l], LDH [1528 U/l], creatinin [1.5 mg/dl] and urea [20 mg/dl] increased in laboratory findings. Despite peridural anaesthesia, the patient complained about increasing pain in the gluteal region and both thighs. His thighs and the gluteal region were swollen. Passive stretch of the thighs caused enormous pain. The compartment pressure was 92 mmHg. Therefore, emergency fasciotomy was performed successfully. The gluteal compartment syndrome was most likely caused by elevated pressure on the gluteal muscle during operation. We suggest heightened awareness of positioning the patient on the operating table is important especially in obese patients with lengthy operating procedures. PMID:16720283

  11. 9 CFR 354.241 - Cleaning of rooms and compartments.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Cleaning of rooms and compartments. 354.241 Section 354.241 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... such regularity as may be necessary to maintain them in a sanitary condition. (f) The killing...

  12. 9 CFR 354.221 - Rooms and compartments.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Rooms and compartments. 354.221 Section 354.221 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... live rabbits or killing operations be permitted in rooms in which eviscerating operations are...

  13. 9 CFR 354.241 - Cleaning of rooms and compartments.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Cleaning of rooms and compartments. 354.241 Section 354.241 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... such regularity as may be necessary to maintain them in a sanitary condition. (f) The killing...

  14. 46 CFR 169.625 - Compartments containing diesel machinery.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Section 169.625 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and Electrical Ventilation § 169.625 Compartments containing diesel machinery..., and be installed so that the ordinary collection of water in the bilge will not trap the duct....

  15. 46 CFR 169.625 - Compartments containing diesel machinery.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Section 169.625 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and Electrical Ventilation § 169.625 Compartments containing diesel machinery..., and be installed so that the ordinary collection of water in the bilge will not trap the duct....

  16. 46 CFR 169.625 - Compartments containing diesel machinery.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Section 169.625 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and Electrical Ventilation § 169.625 Compartments containing diesel machinery..., and be installed so that the ordinary collection of water in the bilge will not trap the duct....

  17. 14 CFR 25.857 - Cargo compartment classification.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... detector or fire detector system to give warning at the pilot or flight engineer station. (c) Class C. A... approved smoke or fire detector system to give warning at the pilot or flight engineer station; (3) There... (2) Each part of the compartment is easily accessible in flight. (b) Class B. A Class B cargo...

  18. 14 CFR 25.857 - Cargo compartment classification.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... detector or fire detector system to give warning at the pilot or flight engineer station. (c) Class C. A... approved smoke or fire detector system to give warning at the pilot or flight engineer station; (3) There... (2) Each part of the compartment is easily accessible in flight. (b) Class B. A Class B cargo...

  19. Miniature galvanic cell construction providing gas channels between electrode compartments

    SciTech Connect

    Urry, L. F.

    1985-03-26

    An improved miniature galvanic cell construction having a sealing gasket with channels defined through the base of the gasket. The channels provide means for the exchange of gaseous products around the cell separator and between the electrode compartments so as to reduce the overall internal pressure of the cell.

  20. 14 CFR 121.269 - Extinguishing agent container compartment temperature.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 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...

  1. 14 CFR 121.269 - Extinguishing agent container compartment temperature.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 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...

  2. 14 CFR 125.167 - Extinguishing agent container compartment temperature.

    Code of Federal Regulations, 2010 CFR

    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...

  3. 14 CFR 125.167 - Extinguishing agent container compartment temperature.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 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...

  4. 14 CFR 125.167 - Extinguishing agent container compartment temperature.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 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...

  5. 14 CFR 125.167 - Extinguishing agent container compartment temperature.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 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...

  6. 14 CFR 121.269 - Extinguishing agent container compartment temperature.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 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...

  7. 14 CFR 121.269 - Extinguishing agent container compartment temperature.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 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...

  8. 14 CFR 125.167 - Extinguishing agent container compartment temperature.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 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...

  9. 14 CFR 121.269 - Extinguishing agent container compartment temperature.

    Code of Federal Regulations, 2010 CFR

    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...

  10. Two-Compartment Pharmacokinetic Models for Chemical Engineers

    ERIC Educational Resources Information Center

    Kanneganti, Kumud; Simon, Laurent

    2011-01-01

    The transport of potassium permanganate between two continuous-stirred vessels was investigated to help chemical and biomedical engineering students understand two-compartment pharmacokinetic models. Concepts of modeling, mass balance, parameter estimation and Laplace transform were applied to the two-unit process. A good agreement was achieved…

  11. FEATURE 3, LARGE GUN POSITION, SHOWING MULTIPLE COMPARTMENTS, VIEW FACING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    FEATURE 3, LARGE GUN POSITION, SHOWING MULTIPLE COMPARTMENTS, VIEW FACING SOUTH (with scale stick). - Naval Air Station Barbers Point, Anti-Aircraft Battery Complex-Large Gun Position, East of Coral Sea Road, northwest of Hamilton Road, Ewa, Honolulu County, HI

  12. Regulating mechanical tension at compartment boundaries in Drosophila.

    PubMed

    Michel, Marcus; Dahmann, Christian

    2016-10-01

    During animal development, cells with similar function and fate often stay together and sort out from cells with different fates. In Drosophila wing imaginal discs, cells of anterior and posterior fates are separated by a straight compartment boundary. Separation of anterior and posterior cells requires the homeodomain-containing protein Engrailed, which is expressed in posterior cells. Engrailed induces the expression of the short-range signaling molecule Hedgehog in posterior cells and confines Hedgehog signal transduction to anterior cells. Transduction of the Hedgehog signal in anterior cells is required for the separation of anterior and posterior cells. Previous work showed that this separation of cells involves a local increase in mechanical tension at cell junctions along the compartment boundary. However, how mechanical tension was locally increased along the compartment boundary remained unknown. A recent paper now shows that the difference in Hedgehog signal transduction between anterior and posterior cells is necessary and sufficient to increase mechanical tension. The local increase in mechanical tension biases junctional rearrangements during cell intercalations to maintain the straight shape of the compartment boundary. These data highlight how developmental signals can generate patterns of mechanical tension important for tissue organization.

  13. 14 CFR 23.853 - Passenger and crew compartment interiors.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Design and Construction Fire Protection § 23.853 Passenger and crew compartment interiors. For each... least fire resistant materials and must contain fires likely to occur in it under normal use. The ability of the disposal receptacle to contain those fires under all probable conditions of...

  14. 46 CFR 174.075 - Compartments assumed flooded: general.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Compartments assumed flooded: general. 174.075 Section 174.075 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO SPECIFIC VESSEL TYPES Special Rules Pertaining to Mobile Offshore...

  15. 46 CFR 174.075 - Compartments assumed flooded: general.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Compartments assumed flooded: general. 174.075 Section 174.075 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO SPECIFIC VESSEL TYPES Special Rules Pertaining to Mobile Offshore...

  16. 9 CFR 354.221 - Rooms and compartments.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Rooms and compartments. 354.221 Section 354.221 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... rabbits are prepared, processed, handled, and stored. (g) Inspector's office. Furnished office...

  17. 14 CFR 27.1193 - Cowling and engine compartment covering.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... must be constructed and supported so that it can resist the vibration, inertia, and air loads to which... least fire resistant. (e) Each part of the cowling or engine compartment covering subject to high temperatures due to its nearness to exhaust system parts or exhaust gas impingement must be fireproof. (f)...

  18. 14 CFR 27.1193 - Cowling and engine compartment covering.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... must be constructed and supported so that it can resist the vibration, inertia, and air loads to which... least fire resistant. (e) Each part of the cowling or engine compartment covering subject to high temperatures due to its nearness to exhaust system parts or exhaust gas impingement must be fireproof. (f)...

  19. 14 CFR 27.1193 - Cowling and engine compartment covering.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... must be constructed and supported so that it can resist the vibration, inertia, and air loads to which... least fire resistant. (e) Each part of the cowling or engine compartment covering subject to high temperatures due to its nearness to exhaust system parts or exhaust gas impingement must be fireproof. (f)...

  20. 14 CFR 27.1193 - Cowling and engine compartment covering.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... must be constructed and supported so that it can resist the vibration, inertia, and air loads to which... least fire resistant. (e) Each part of the cowling or engine compartment covering subject to high temperatures due to its nearness to exhaust system parts or exhaust gas impingement must be fireproof. (f)...

  1. 14 CFR 27.1193 - Cowling and engine compartment covering.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... must be constructed and supported so that it can resist the vibration, inertia, and air loads to which... least fire resistant. (e) Each part of the cowling or engine compartment covering subject to high temperatures due to its nearness to exhaust system parts or exhaust gas impingement must be fireproof. (f)...

  2. Is a mosaic embryo also a mosaic of communication compartments?

    PubMed

    Serras, F; van den Biggelaar, J A

    1987-03-01

    We have studied the pathways of cell communication in embryos of the mollusc Lymnaea stagnalis in which the developmental fate of a cell or a group of cells is known from cell lineage studies. We iontophoretically injected Lucifer Yellow CH and followed the spread of fluorescence between cells interconnected via gap junctions. In early stages all blastomeres appear to be dye-coupled, but later on communication is restricted within compartments. The pattern of cell communication corresponds with the development of compartments with specific cell fates. Dye-spread is limited by communication boundaries which completely or mostly prevent the passage of dye to adjacent compartments with different developmental fates. These boundaries appear progressively during development. Our results suggest that, during the development of Lymnaea, the progressive changes in the pattern of dye spread correspond with the progressive restrictions of the developmental fates of individual cells or groups of cells. We conclude that changes in the pattern of cell communication and in the appearance of communication compartments are not exclusive features of regulative embryos. PMID:3817285

  3. Characterizations of intracellular arsenic in a bacterium

    NASA Astrophysics Data System (ADS)

    Wolfe-Simon, F.; Yannone, S. M.; Tainer, J. A.

    2011-12-01

    Life requires a key set of chemical elements to sustain growth. Yet, a growing body of literature suggests that microbes can alter their nutritional requirements based on the availability of these chemical elements. Under limiting conditions for one element microbes have been shown to utilize a variety of other elements to serve similar functions often (but not always) in similar molecular structures. Well-characterized elemental exchanges include manganese for iron, tungsten for molybdenum and sulfur for phosphorus or oxygen. These exchanges can be found in a wide variety of biomolecules ranging from protein to lipids and DNA. Recent evidence suggested that arsenic, as arsenate or As(V), was taken up and incorporated into the cellular material of the bacterium GFAJ-1. The evidence was interpreted to support As(V) acting in an analogous role to phosphate. We will therefore discuss our ongoing efforts to characterize intracellular arsenate and how it may partition among the cellular fractions of the microbial isolate GFAJ-1 when exposed to As(V) in the presence of various levels of phosphate. Under high As(V) conditions, cells express a dramatically different proteome than when grown given only phosphate. Ongoing studies on the diversity and potential role of proteins and metabolites produced in the presence of As(V) will be reported. These investigations promise to inform the role and additional metabolic potential for As in biology. Arsenic assimilation into biomolecules contributes to the expanding set of chemical elements utilized by microbes in unusual environmental niches.

  4. Intracellular Organisms as Placental Invaders

    PubMed Central

    Vigliani, Marguerite B.; Bakardjiev, Anna I.

    2015-01-01

    In this article we present a novel model for how the human placenta might get infected via the hematogenous route. We present a list of diverse placental pathogens, like Listeria monocytogenes or Cytomegalovirus, which are familiar to most obstetricians, but others, like Salmonella typhi, have only been reported in case studies or small case series. Remarkably, all of these organisms on this list are either obligate or facultative intracellular organisms. These pathogens are able to enter and survive inside host immune cells for at least a portion of their life cycle. We suggest that many blood-borne pathogens might arrive at the placenta via transportation inside of maternal leukocytes that enter the decidua in early pregnancy. We discuss mechanisms by which extravillous trophoblasts could get infected in the decidua and spread infection to other layers in the placenta. We hope to raise awareness among OB/GYN clinicians that organisms not typically associated with the TORCH list might cause placental infections and pregnancy complications.

  5. Secretome of obligate intracellular Rickettsia

    PubMed Central

    Gillespie, Joseph J.; Kaur, Simran J.; Rahman, M. Sayeedur; Rennoll-Bankert, Kristen; Sears, Khandra T.; Beier-Sexton, Magda; Azad, Abdu F.

    2014-01-01

    The genus Rickettsia (Alphaproteobacteria, Rickettsiales, Rickettsiaceae) is comprised of obligate intracellular parasites, with virulent species of interest both as causes of emerging infectious diseases and for their potential deployment as bioterrorism agents. Currently, there are no effective commercially available vaccines, with treatment limited primarily to tetracycline antibiotics, although others (e.g. josamycin, ciprofloxacin, chloramphenicol, and azithromycin) are also effective. Much of the recent research geared toward understanding mechanisms underlying rickettsial pathogenicity has centered on characterization of secreted proteins that directly engage eukaryotic cells. Herein, we review all aspects of the Rickettsia secretome, including six secretion systems, 19 characterized secretory proteins, and potential moonlighting proteins identified on surfaces of multiple Rickettsia species. Employing bioinformatics and phylogenomics, we present novel structural and functional insight on each secretion system. Unexpectedly, our investigation revealed that the majority of characterized secretory proteins have not been assigned to their cognate secretion pathways. Furthermore, for most secretion pathways, the requisite signal sequences mediating translocation are poorly understood. As a blueprint for all known routes of protein translocation into host cells, this resource will assist research aimed at uniting characterized secreted proteins with their apposite secretion pathways. Furthermore, our work will help in the identification of novel secreted proteins involved in rickettsial ‘life on the inside’. PMID:25168200

  6. Dynamics of intracellular information decoding

    NASA Astrophysics Data System (ADS)

    Kobayashi, Tetsuya J.; Kamimura, Atsushi

    2011-10-01

    A variety of cellular functions are robust even to substantial intrinsic and extrinsic noise in intracellular reactions and the environment that could be strong enough to impair or limit them. In particular, of substantial importance is cellular decision-making in which a cell chooses a fate or behavior on the basis of information conveyed in noisy external signals. For robust decoding, the crucial step is filtering out the noise inevitably added during information transmission. As a minimal and optimal implementation of such an information decoding process, the autocatalytic phosphorylation and autocatalytic dephosphorylation (aPadP) cycle was recently proposed. Here, we analyze the dynamical properties of the aPadP cycle in detail. We describe the dynamical roles of the stationary and short-term responses in determining the efficiency of information decoding and clarify the optimality of the threshold value of the stationary response and its information-theoretical meaning. Furthermore, we investigate the robustness of the aPadP cycle against the receptor inactivation time and intrinsic noise. Finally, we discuss the relationship among information decoding with information-dependent actions, bet-hedging and network modularity.

  7. Fatty Acid Signaling: The New Function of Intracellular Lipases

    PubMed Central

    Papackova, Zuzana; Cahova, Monika

    2015-01-01

    Until recently, intracellular triacylglycerols (TAG) stored in the form of cytoplasmic lipid droplets have been considered to be only passive “energy conserves”. Nevertheless, degradation of TAG gives rise to a pleiotropic spectrum of bioactive intermediates, which may function as potent co-factors of transcription factors or enzymes and contribute to the regulation of numerous cellular processes. From this point of view, the process of lipolysis not only provides energy-rich equivalents but also acquires a new regulatory function. In this review, we will concentrate on the role that fatty acids liberated from intracellular TAG stores play as signaling molecules. The first part provides an overview of the transcription factors, which are regulated by fatty acids derived from intracellular stores. The second part is devoted to the role of fatty acid signaling in different organs/tissues. The specific contribution of free fatty acids released by particular lipases, hormone-sensitive lipase, adipose triacylglycerol lipase and lysosomal lipase will also be discussed. PMID:25674855

  8. A DNA-Device that Mediates Selective Endosomal Escape and Intracellular Delivery of Drugs and Biologicals

    PubMed Central

    Muro, Silvia

    2014-01-01

    Design of materials to aid intracellular delivery of agents can greatly improve medical treatments. While DNA is a molecule difficult to introduce into cells, DNA can be engineered into devices capable of intracellular delivery. Yet, transport mediated by DNA-devices void of other structural material, with size greater than that associated with non-specific penetration, and with targeting capacity enough to overcome non-specific pathways has not been achived. This study demonstrates that this is possible. Submicrometer (200-nm) dendrimers built of DNA (nucleodendrimers (NDs)) are coupled to antibodies against selected cell-surface receptors and compared to polymer nanoparticles (NPs). NDs and NPs bind specifically to cells expressing these targets and efficiently enter cells via the pathway associated with the selected receptor. While NPs traffic to perinuclear endo-lysosomes, NDs remain scattered throughout the cell, suggesting endosomal escape. This is confirmed in vitro, where NDs disrupt membranous vesicles at endosomal-like pH and in cell culture, where they: provide endosomal escape of model drugs, sugars, proteins, and nucleic acids; allow access to other intracellular compartments; result in measurable effects of cargoes; and do not cause cytotoxicity. Therefore, these DNA-nanodevices can be used to selectively overcome intracellular barriers, underscoring the growing range of applications of DNA materials. PMID:25018687

  9. The Brucella suis virB operon is induced intracellularly in macrophages.

    PubMed

    Boschiroli, Maria Laura; Ouahrani-Bettache, Safia; Foulongne, Vincent; Michaux-Charachon, Sylvie; Bourg, Gisele; Allardet-Servent, Annick; Cazevieille, Chantal; Liautard, Jean Pierre; Ramuz, Michel; O'Callaghan, David

    2002-02-01

    A type IV secretion system similar to the VirB system of the phytopathogen Agrobacterium tumefaciens is essential for the intracellular survival and multiplication of the mammalian pathogen Brucella. Reverse transcriptase-PCR showed that the 12 genes encoding the Brucella suis VirB system form an operon. Semiquantitative measurements of virB mRNA levels by slot blotting showed that transcription of the virB operon, but not the flanking genes, is regulated by environmental factors in vitro. Flow cytometry used to measure green fluorescent protein expression from the virB promoter confirmed the data from slot blots. Fluorescence-activated cell sorter analysis and fluorescence microscopy showed that the virB promoter is induced in macrophages within 3 h after infection. Induction only occurred once the bacteria were inside the cells, and phagosome acidification was shown to be the major signal inducing intracellular expression. Because phagosome acidification is essential for the intracellular multiplication of Brucella, we suggest that it is the signal that triggers the secretion of unknown effector molecules. These effector molecules play a role in the remodeling of the phagosome to create the unique intracellular compartment in which Brucella replicates. PMID:11830669

  10. A DNA-Device that Mediates Selective Endosomal Escape and Intracellular Delivery of Drugs and Biologicals.

    PubMed

    Muro, Silvia

    2014-05-21

    Design of materials to aid intracellular delivery of agents can greatly improve medical treatments. While DNA is a molecule difficult to introduce into cells, DNA can be engineered into devices capable of intracellular delivery. Yet, transport mediated by DNA-devices void of other structural material, with size greater than that associated with non-specific penetration, and with targeting capacity enough to overcome non-specific pathways has not been achived. This study demonstrates that this is possible. Submicrometer (200-nm) dendrimers built of DNA (nucleodendrimers (NDs)) are coupled to antibodies against selected cell-surface receptors and compared to polymer nanoparticles (NPs). NDs and NPs bind specifically to cells expressing these targets and efficiently enter cells via the pathway associated with the selected receptor. While NPs traffic to perinuclear endo-lysosomes, NDs remain scattered throughout the cell, suggesting endosomal escape. This is confirmed in vitro, where NDs disrupt membranous vesicles at endosomal-like pH and in cell culture, where they: provide endosomal escape of model drugs, sugars, proteins, and nucleic acids; allow access to other intracellular compartments; result in measurable effects of cargoes; and do not cause cytotoxicity. Therefore, these DNA-nanodevices can be used to selectively overcome intracellular barriers, underscoring the growing range of applications of DNA materials.

  11. Identification of a transcriptional regulator that controls intracellular gene expression in Salmonella Typhi.

    PubMed

    Haghjoo, Erik; Galán, Jorge E

    2007-06-01

    Salmonella enterica serovar Typhi (S. Typhi), the aetiological agent of typhoid fever, is an exclusively human pathogen. Little is known about specific factors that may confer to this bacterium its unique pathogenic features. One of these determinants is CdtB, a homologue of the active subunit of the cytolethal distending toxin, which causes DNA damage leading to cell cycle arrest and distension of intoxicated cells. A unique property of S. Typhi CdtB is that it is only synthesized when this bacterium is within an intracellular compartment. Through a genetic screen, we have identified a transcriptional regulatory protein that controls the intracellular expression of cdtB. This regulator, which we have named IgeR, is a member of the DeoR family of transcriptional regulatory proteins and is highly conserved in all S. enterica serovars. IgeR directly binds the cdtB promoter and represses its expression in the extracellular environment. Microarray analysis identified additional IgeR-regulated genes that are involved in virulence. Constitutive expression of igeR resulted in the reduction of intracellular expression of cdtB by S. Typhi and in significant impairment of the virulence of Salmonella enterica serovar Typhimurium (S. Typhimurium) in mice. We propose that IgeR may co-ordinate gene expression during Salmonella's transition from an extracellular to an intracellular environment. PMID:17555437

  12. Hydrophilic fluorescent nanogel thermometer for intracellular thermometry.

    PubMed

    Gota, Chie; Okabe, Kohki; Funatsu, Takashi; Harada, Yoshie; Uchiyama, Seiichi

    2009-03-01

    The first methodology to measure intracellular temperature is described. A highly hydrophilic fluorescent nanogel thermometer developed for this purpose stays in the cytoplasm and emits stronger fluorescence at a higher temperature. Thus, intracellular temperature variations associated with biological processes can be monitored by this novel thermometer with a temperature resolution of better than 0.5 degrees C.

  13. Anatomic variation of the 5th extensor tendon compartment and extensor digiti minimi tendon.

    PubMed

    Tanaka, Toshikazu; Moran, Steven L; Zhao, Chunfeng; Zobitz, Mark E; An, Kai-Nan; Amadio, Peter C

    2007-08-01

    Anatomic variation within the 5th extensor compartment may contribute to the development of tenosynovitis and limit the usefulness of the extensor digiti minimi (EDM) for tendon transfer. The purpose of this study was to assess the anatomic variation of the EDM tendon and its surrounding retinaculum, with particular attention to anatomical variation between specimens. Forty-one fresh cadaver hands were dissected. The length of the 5th compartment retinaculum was noted. The incidence of an intercompartmental septum was noted in each specimen as well as the type of tendinous attachments present between the EDM and extensor digitorum communis (EDC) tendons. The presence and length of any accessory retinacular bands distal to the edge of proper extensor retinaculum was also noted. Only one specimen contained a single EDM tendon, while 71% (n = 29) of specimens contained two slips and 23% (n = 9) had three slips; 24% (n = 10) of EDC tendons had no slip to the small finger, while 61% (n = 25) of specimens had a single slip to the small finger. The EDC's contribution to the small finger was found to be an independent tendon in 42% of cases (n = 17), while 34% (n = 14) of specimens were found to have a common EDC slip, which branched to both the ring and small finger. Three EDM tendons divided distal to the extensor retinaculum, while the remaining EDM tendons divided beneath or proximal to the extensor retinaculum. Seventy-three percent (n = 30) of the specimens had an accessory retinacular band surrounding the EDM tendon identified at the base of the 5th metacarpal. Eighty-eight percent (n = 36) of hands had a septum between the EDM slips. The surgeon should be aware of variability within the 5th dorsal compartment in cases of trauma and in cases of tendon transfer. In our series 30 of 41 specimens were noted to contain an accessory dorsal retinacular band surrounding the EDM and 36 specimens were noted to contain a septum within the 5th compartment. The presence of an

  14. Highly potent intracellular membrane-associated Aβ seeds

    PubMed Central

    Marzesco, Anne-Marie; Flötenmeyer, Matthias; Bühler, Anika; Obermüller, Ulrike; Staufenbiel, Matthias; Jucker, Mathias; Baumann, Frank

    2016-01-01

    An early event in Alzheimer’s disease (AD) pathogenesis is the formation of extracellular aggregates of amyloid-β peptide (Aβ), thought to be initiated by a prion-like seeding mechanism. However, the molecular nature and location of the Aβ seeds remain rather elusive. Active Aβ seeds are found in crude homogenates of amyloid-laden brains and in the soluble fraction thereof. To analyze the seeding activity of the pellet fraction, we have either separated or directly immunoisolated membranes from such homogenates. Here, we found considerable Aβ seeding activity associated with membranes in the absence of detectable amyloid fibrils. We also found that Aβ seeds on mitochondrial or associated membranes efficiently induced Aβ aggregation in vitro and seed β-amyloidosis in vivo. Aβ seeds at intracellular membranes may contribute to the spreading of Aβ aggregation along neuronal pathways and to the induction of intracellular pathologies downstream of Aβ. PMID:27311744

  15. Trypanosoma cruzi infection results in an increase in intracellular cholesterol

    PubMed Central

    Johndrow, Christopher; Nelson, Randin; Tanowitz, Herbert; Weiss, Louis; Nagajyothi, Fnu

    2014-01-01

    Chagasic cardiomyopathy caused by Trypanosoma cruzi is a major health concern in Latin America and among immigrant populations in non-endemic areas. T. cruzi has a high affinity for host lipoproteins and uses the low density lipoprotein receptor (LDLr) for invasion. Herein, we report that T. cruzi infection is associated with an accumulation of LDL and cholesterol in tissues in both acute and chronic murine Chagas disease. Similar findings were observed in tissue samples from a human case of Chagasic cardiomyopathy. T. cruzi infection of cultured cells displayed increased invasion with increasing cholesterol levels in the medium. Studies of infected host cells demonstrated alterations in their cholesterol regulation. T. cruzi invasion/infection via LDLr appears to be involved in changes in intracellular cholesterol homeostasis. The observed changes in intracellular lipids and associated oxidative stress due to these elevated lipids may contribute to the development of Chagasic cardiomyopathy. PMID:24486184

  16. Intracellular structure and nucleocytoplasmic transport.

    PubMed

    Agutter, P S

    1995-01-01

    Intracellular movement of any solute or particle accords with one of two general schemes: either it takes place predominantly in the solution phase or it occurs by dynamic interactions with solid-state structures. If nucleocytoplasmic exchanges of macromolecules and complexes are predominantly solution-phase processes, i.e., if the former ("diffusionist") perspective applies, then the only significant structures in nucleocytoplasmic transport are the pore complexes. However, if such exchanges accord with the latter ("solid-state") perspective, then the roles of the nucleoskeleton and cytoskeleton in nucleocytoplasmic transport are potentially, at least, as important as that of the pore complexes. The role of the nucleoskeleton in mRNA transport is more difficult to evaluate than that of the cytoskeleton because it is less well characterized, and current evidence does not exclude either perspective. However, the balance of evidence favors a solid-state scheme. It is argued that ribosomal subunits are also more likely to migrate by a solid-state rather than a diffusionist mechanism, though the opposite is true of proteins and tRNAs. Moreover, recent data on the effects of viral proteins on intranuclear RNA processing and migration accord with the solid-state perspective. In view of this balance of evidence, three possible solid-state mechanisms for nucleocytoplasmic mRNA transport are described and evaluated. The explanatory advantage of solid-state models is contrasted with the heuristic advantage of diffusion theory, but it is argued that diffusion theory itself, even aided by modern computational techniques and numerical and graphical approaches, cannot account for data describing the movements of materials within the cell. Therefore, the mechanisms envisaged in a diffusionist perspective cannot be confined to diffusion alone, but must include other processes such as bulk fluid flow.

  17. Striatal patch compartment lesions alter methamphetamine-induced behavior and immediate early gene expression in the striatum, substantia nigra and frontal cortex.

    PubMed

    Murray, Ryan C; Gilbert, Yamiece E; Logan, Anna S; Hebbard, John C; Horner, Kristen A

    2014-07-01

    Methamphetamine (METH) induces stereotypy, which is characterized as inflexible, repetitive behavior. Enhanced activation of the patch compartment of the striatum has been correlated with stereotypy, suggesting that stereotypy may be related to preferential activation of this region. However, the specific contribution of the patch compartment to METH-induced stereotypy is not clear. To elucidate the involvement of the patch compartment to the development of METH-induced stereotypy, we determined if destruction of this sub-region altered METH-induced behaviors. Animals were bilaterally infused in the striatum with the neurotoxin dermorphin-saporin (DERM-SAP; 17 ng/μl) to specifically ablate the neurons of the patch compartment. Eight days later, animals were treated with METH (7.5 mg/kg), placed in activity chambers, observed for 2 h and killed. DERM-SAP pretreatment significantly reduced the number and total area of mu-labeled patches in the striatum. DERM-SAP pretreatment significantly reduced the intensity of METH-induced stereotypy and the spatial immobility typically observed with METH-induced stereotypy. In support of this observation, DERM-SAP pretreatment also significantly increased locomotor activity in METH-treated animals. In the striatum, DERM-SAP pretreatment attenuated METH-induced c-Fos expression in the patch compartment, while enhancing METH-induced c-Fos expression in the matrix compartment. DERM-SAP pretreatment followed by METH administration augmented c-Fos expression in the SNpc and reduced METH-induced c-Fos expression in the SNpr. In the medial prefrontal, but not sensorimotor cortex, c-Fos and zif/268 expression was increased following METH treatment in animals pre-treated with DERM-SAP. These data indicate that the patch compartment is necessary for the expression of repetitive behaviors and suggests that alterations in activity in the basal ganglia may contribute to this phenomenon.

  18. Single Point Mutations Result in the Miss-Sorting of Glut4 to a Novel Membrane Compartment Associated with Stress Granule Proteins

    PubMed Central

    Song, XiaoMei; Lichti, Cheryl F.; Townsend, R. Reid; Mueckler, Mike

    2013-01-01

    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. PMID:23874650

  19. Quantification of different classical swine fever virus transmission routes within a single compartment.

    PubMed

    Weesendorp, Eefke; Backer, Jantien; Loeffen, Willie

    2014-12-01

    During outbreaks of classical swine fever (CSF), CSF virus (CSFV) can be transmitted via different routes. Understanding these transmission routes is crucial in preventing the unlimited spread of the virus in a naïve population, and the subsequent eradication of the virus from that population. The objectives of the present study were to quantify virus transmission within a compartment, differentiating between transmission within a pen, transmission between pens via contact through (open) pen partitions, and transmission via the air. Furthermore, the possible contribution of each of these routes to infection of individual pigs was quantified. A CSFV outbreak was mimicked in a compartment housing 24 pigs in six different pens. Two pigs in one pen were inoculated with the moderately virulent Paderborn strain, and virus transmission to other pigs was followed in time. Virus transmission rates for transmission via the air (β of 0.33 (0.14-0.64) per day) and transmission between adjacent pens (β of 0.30 (0-0.88) per day) were comparable, but significantly lower than for virus transmission within a pen (β of 6.1 (0.86-18) per day). The route via the air created new focal points of infection, from which virus transmission continued through other routes. This shows that, at least within a compartment, transmission via the air is expected to play a relevant role in the fast spread of the virus after an initial slow start. This will have consequences for efficacy of intervention measures, including vaccination during an outbreak.

  20. Microfluidic single-cell analysis of intracellular compounds

    PubMed Central

    Chao, Tzu-Chiao; Ros, Alexandra

    2008-01-01

    Biological analyses traditionally probe cell ensembles in the range of 103–106 cells, thereby completely averaging over relevant individual cell responses, such as differences in cell proliferation, responses to external stimuli or disease onset. In past years, this fact has been realized and increasing interest has evolved for single-cell analytical methods, which could give exciting new insights into genomics, proteomics, transcriptomics and systems biology. Microfluidic or lab-on-a-chip devices are the method of choice for single-cell analytical tools as they allow the integration of a variety of necessary process steps involved in single-cell analysis, such as selection, navigation, positioning or lysis of single cells as well as separation and detection of cellular analytes. Along with this advantageous integration, microfluidic devices confine single cells in compartments near their intrinsic volume, thus minimizing dilution effects and increasing detection sensitivity. This review overviews the developments and achievements of microfluidic single-cell analysis of intracellular compounds in the past few years, from proof-of-principle devices to applications demonstrating a high biological relevance. PMID:18682362

  1. Sequestration of host metabolism by an intracellular pathogen

    PubMed Central

    Gehre, Lena; Gorgette, Olivier; Perrinet, Stéphanie; Prevost, Marie-Christine; Ducatez, Mathieu; Giebel, Amanda M; Nelson, David E; Ball, Steven G; Subtil, Agathe

    2016-01-01

    For intracellular pathogens, residence in a vacuole provides a shelter against cytosolic host defense to the cost of limited access to nutrients. The human pathogen Chlamydia trachomatis grows in a glycogen-rich vacuole. How this large polymer accumulates there is unknown. We reveal that host glycogen stores shift to the vacuole through two pathways: bulk uptake from the cytoplasmic pool, and de novo synthesis. We provide evidence that bacterial glycogen metabolism enzymes are secreted into the vacuole lumen through type 3 secretion. Our data bring strong support to the following scenario: bacteria co-opt the host transporter SLC35D2 to import UDP-glucose into the vacuole, where it serves as substrate for de novo glycogen synthesis, through a remarkable adaptation of the bacterial glycogen synthase. Based on these findings we propose that parasitophorous vacuoles not only offer protection but also provide a microorganism-controlled metabolically active compartment essential for redirecting host resources to the pathogens. DOI: http://dx.doi.org/10.7554/eLife.12552.001 PMID:26981769

  2. Intracellular shuttling and mitochondrial function of thioredoxin-interacting protein.

    PubMed

    Saxena, Geetu; Chen, Junqin; Shalev, Anath

    2010-02-01

    The thioredoxin-interacting protein TXNIP is a ubiquitously expressed redox protein that promotes apoptosis. Recently, we found that TXNIP deficiency protects against type 1 and 2 diabetes by inhibiting beta cell apoptosis and maintaining pancreatic beta cell mass, indicating that TXNIP plays a key role in beta cell biology. However, very little is known about the intracellular localization and function of TXNIP, and although TXNIP has been thought to be a cytoplasmic protein, our immunohistochemistry studies in beta cells surprisingly revealed a nuclear TXNIP localization, suggesting that TXNIP may shuttle within the cell. Using immunohistochemistry/confocal imaging and cell fractionation/co-immunoprecipitation, we found that, under physiological conditions, TXNIP is localized primarily in the nucleus of pancreatic beta cells, whereas oxidative stress leads to TXNIP shuttling into the mitochondria. In mitochondria, TXNIP binds to and oxidizes Trx2, thereby reducing Trx2 binding to ASK1 and allowing for ASK1 phosphorylation/activation, resulting in induction of the mitochondrial pathway of apoptosis with cytochrome c release and caspase-3 cleavage. TXNIP overexpression and Trx2 (but not cytosolic Trx1) silencing mimic these effects. Thus, we discovered that TXNIP shuttles between subcellular compartments in response to oxidative stress and identified a novel redox-sensitive mitochondrial TXNIP-Trx2-ASK1 signaling cascade.

  3. Shedding PEG Palisade by Temporal Photostimulation and Intracellular Reducing Milieu for Facilitated Intracellular Trafficking and DNA Release.

    PubMed

    Wang, Tieyan; Chen, Qixian; Lu, Hongguang; Li, Wei; Li, Zaifen; Ma, Jianbiao; Gao, Hui

    2016-08-17

    The dilemma of poly(ethylene glycol) surface modification (PEGylation) inspired us to develop an intracellularly sheddable PEG palisade for synthetic delivery systems. Here, we attempted to conjugate PEG to polyethylenimine (PEI) through tandem linkages of disulfide-bridge susceptible to cytoplasmic reduction and an azobenzene/cyclodextrin inclusion complex responsive to external photoirradiation. The subsequent investigations revealed that facile PEG detachment could be achieved in endosomes upon photoirradiation, consequently engendering exposure of membrane-disruptive PEI for facilitated endosome escape. The liberated formulation in the cytosol was further subjected to complete PEG detachment relying on disulfide cleavage in the reductive cytosol, thus accelerating dissociation of electrostatically assembled PEI/DNA polyplex to release DNA by means of polyion exchange reaction with intracellularly charged species, ultimately contributing to efficient gene expression.

  4. Shedding PEG Palisade by Temporal Photostimulation and Intracellular Reducing Milieu for Facilitated Intracellular Trafficking and DNA Release.

    PubMed

    Wang, Tieyan; Chen, Qixian; Lu, Hongguang; Li, Wei; Li, Zaifen; Ma, Jianbiao; Gao, Hui

    2016-08-17

    The dilemma of poly(ethylene glycol) surface modification (PEGylation) inspired us to develop an intracellularly sheddable PEG palisade for synthetic delivery systems. Here, we attempted to conjugate PEG to polyethylenimine (PEI) through tandem linkages of disulfide-bridge susceptible to cytoplasmic reduction and an azobenzene/cyclodextrin inclusion complex responsive to external photoirradiation. The subsequent investigations revealed that facile PEG detachment could be achieved in endosomes upon photoirradiation, consequently engendering exposure of membrane-disruptive PEI for facilitated endosome escape. The liberated formulation in the cytosol was further subjected to complete PEG detachment relying on disulfide cleavage in the reductive cytosol, thus accelerating dissociation of electrostatically assembled PEI/DNA polyplex to release DNA by means of polyion exchange reaction with intracellularly charged species, ultimately contributing to efficient gene expression. PMID:27453033

  5. Intracellular delivery and trafficking dynamics of a lymphoma-targeting antibody-polymer conjugate.

    PubMed

    Berguig, Geoffrey Y; Convertine, Anthony J; Shi, Julie; Palanca-Wessels, Maria Corinna; Duvall, Craig L; Pun, Suzie H; Press, Oliver W; Stayton, Patrick S

    2012-12-01

    Ratiometric fluorescence and cellular fractionation studies were employed to characterize the intracellular trafficking dynamics of antibody-poly(propylacrylic acid) (PPAA) conjugates in CD22+ RAMOS-AW cells. The HD39 monoclonal antibody (mAb) directs CD22-dependent, receptor-mediated uptake in human B-cell lymphoma cells, where it is rapidly trafficked to the lysosomal compartment. To characterize the intracellular-release dynamics of the polymer-mAb conjugates, HD39-streptavidin (HD39/SA) was dual-labeled with pH-insensitive Alexa Fluor 488 and pH-sensitive pHrodo fluorophores. The subcellular pH distribution of the HD39/SA-polymer conjugates was quantified as a function of time by live-cell fluorescence microscopy, and the average intracellular pH value experienced by the conjugates was also characterized as a function of time by flow cytometry. PPAA was shown to alter the intracellular trafficking kinetics strongly relative to HD39/SA alone or HD39/SA conjugates with a control polymer, poly(methacryclic acid) (PMAA). Subcellular trafficking studies revealed that after 6 h, only 11% of the HD39/SA-PPAA conjugates had been trafficked to acidic lysosomal compartments with values at or below pH 5.6. In contrast, the average intracellular pH of HD39/SA alone dropped from 6.7 ± 0.2 at 1 h to 5.6 ± 0.5 after 3 h and 4.7 ± 0.6 after 6 h. Conjugation of the control polymer PMAA to HD39/SA showed an average pH drop similar to that of HD39/SA. Subcellular fractionation studies with tritium-labeled HD39/SA demonstrated that after 6 h, 89% of HD39/SA was associated with endosomes (Rab5+) and lysosomes (Lamp2+), while 45% of HD39/SA-PPAA was translocated to the cytosol (lactate dehydrogenase+). These results demonstrate the endosomal-releasing properties of PPAA with antibody-polymer conjugates and detail their intracellular trafficking dynamics and subcellular compartmental distributions over time.

  6. Head and neck fascia and compartments: no space for spaces.

    PubMed

    Guidera, Alice K; Dawes, Patrick J D; Fong, Amy; Stringer, Mark D

    2014-07-01

    An accurate understanding of the arrangement of cervical fascia and its associated compartments is essential for differential diagnosis, predicting the spread of disease, and surgical management. The purpose of this detailed review is to summarize the anatomic, clinical, and radiological literature to determine what is known about the arrangement of cervical fascia and to highlight controversies and consensus. The current terminology used to describe cervical fascia and compartments is replete with confusing synonyms and inconsistencies, creating important interdisciplinary differences in understanding. The term "spaces" is inappropriate. A modified nomenclature underpinned by evidence-based anatomic and radiologic findings is proposed. This should not only enhance our understanding of cervical anatomy but also facilitate clearer interdisciplinary communication.

  7. Experimental study on elevated fires in a ceiling vented compartment

    NASA Astrophysics Data System (ADS)

    Zhang, Jiaqing; Lu, Shouxiang; Li, Qiang; Li, Changhai; Yuan, Man; Yuen, Richard

    2013-08-01

    The impacts of elevation on fires in a ceiling vented compartment were investigated experimentally. The flame behavior of elevated fires was recorded. Various parameters including the fuel mass loss rate, the light extinction coefficient, the oxygen concentration and the gas temperature were measured. Results indicated that the variations of the flame behavior were consistent with that of the fuel mass loss rate. The fire location significantly impacted the light extinction coefficient, the oxygen concentration and the gas temperature, which all showed distinct stratification phenomena. For a higher elevated fire, the average fuel loss rate and the overall light extinction coefficient were smaller, the oxygen concentration was higher and the gas temperature was lower. In addition, the smoke descending was slower. From the perspective of those parameters the fire was less hazardous if the fire was elevated higher, which was totally different from the elevated fires in closed compartments.

  8. Compartment syndrome with mononeuropathies after anterior cruciate ligament reconstruction.

    PubMed

    Kindle, Brett J; Murthy, Naveen; Stolp, Kathryn

    2015-05-01

    Compartment syndrome rarely follows anterior cruciate ligament reconstruction. However, when it does, it may result in mononeuropathies that are amenable to neurolysis. The authors of this study present an 18-yr-old woman who sustained a right anterior cruciate ligament tear and underwent uneventful anterior cruciate ligament reconstruction using femoral and popliteal nerve blocks. Postoperatively, she developed compartment syndrome requiring emergent fasciotomies. At 11 wks after fasciotomy, results of electrophysiologic tests showed evidence of severe fibular and tibial neuropathies. Magnetic resonance images showed extensive tricompartmental myonecrosis. Fibular and tibial neurolysis as well as decompression were performed, followed by intensive outpatient rehabilitation. At the 6-mo follow-up, she reported resolution of pain as well as significant improvement in sensation, strength, and function. Early recognition and intervention are crucial to prevent serious neurologic damage. Excessive tourniquet pressure and anesthetic nerve blocks may have been responsible.

  9. p73-induced apoptosis: A question of compartments and cooperation

    SciTech Connect

    Dobbelstein, Matthias; Strano, Sabrina; Roth, Judith; Blandino, Giovanni . E-mail: blandino@ifo.it

    2005-06-10

    The transcriptionally active forms of p73 are capable of inducing apoptosis, and the isoforms termed TAp73 are important players when E2F and its oncogenic activators induce programmed cell death. However, the conditions under that TAp73 can kill a cell remain to be clarified. Recently, it has been found that p73 proteins are not merely floating in the nucleoplasm but rather can associate with specific compartments in the cell. Examples of intranuclear compartments associated with p73 proteins include the PML oncogenic domains and the nuclear matrix. In addition, p73 is found in the cytoplasm. It remains to be seen whether p73 might also associate with mitochondria, in analogy with p53. The relocalization of p73 is expected to be mediated by specific binding partners, mostly other proteins. Here, we discuss the possibility that the compartmentalization of p73, and the cooperation with the corresponding binding partners, might decide about its apoptosis-inducing activity.

  10. Spontaneous bilateral compartment syndrome in a HIV-positive patient.

    PubMed

    Davidson, Donald James; Shaukat, Yasir Mehmood; Jenabzadeh, Reza; Gupte, Chinmay M

    2013-01-01

    Spontaneous bilateral compartment syndrome is a very rare condition but one which requires swift diagnosis and urgent surgical decompression by fasciotomies in order to achieve the best outcome. We present the case of a 31-year-old HIV-positive man. The case highlights the perils of being sidetracked by an atypical clinical history instead of acting on the classical clinical examination findings. We will discuss the presentation and management of this patient, review the literature and highlight the key learning points. The most important learning point being that no matter how atypical the history, if a patient presents with limb pain out of proportion to the injury (with or without pain on passive stretch), sensory changes and a loss of motor power, then a diagnosis of acute compartment syndrome must be considered.

  11. Cilioplasm is a cellular compartment for calcium signaling in response to mechanical and chemical stimuli.

    PubMed

    Jin, Xingjian; Mohieldin, Ashraf M; Muntean, Brian S; Green, Jill A; Shah, Jagesh V; Mykytyn, Kirk; Nauli, Surya M

    2014-06-01

    Primary cilia with a diameter of ~200 nm have been implicated in development and disease. Calcium signaling within a primary cilium has never been directly visualized and has therefore remained a speculation. Fluid-shear stress and dopamine receptor type-5 (DR5) agonist are among the few stimuli that require cilia for intracellular calcium signal transduction. However, it is not known if these stimuli initiate calcium signaling within the cilium or if the calcium signal originates in the cytoplasm. Using an integrated single-cell imaging technique, we demonstrate for the first time that calcium signaling triggered by fluid-shear stress initiates in the primary cilium and can be distinguished from the subsequent cytosolic calcium response through the ryanodine receptor. Importantly, this flow-induced calcium signaling depends on the ciliary polycystin-2 calcium channel. While DR5-specific agonist induces calcium signaling mainly in the cilioplasm via ciliary CaV1.2, thrombin specifically induces cytosolic calcium signaling through the IP3 receptor. Furthermore, a non-specific calcium ionophore triggers both ciliary and cytosolic calcium responses. We suggest that cilia not only act as sensory organelles but also function as calcium signaling compartments. Cilium-dependent signaling can spread to the cytoplasm or be contained within the cilioplasm. Our study thus provides the first model to understand signaling within the cilioplasm of a living cell.

  12. The role of the cell wall compartment in mutualistic symbioses of plants

    PubMed Central

    Rich, Mélanie K.; Schorderet, Martine; Reinhardt, Didier

    2014-01-01

    Plants engage in mutualistic interactions with microbes that improve their mineral nutrient supply. The most wide-spread symbiotic association is arbuscular mycorrhiza (AM), in which fungi of the order Glomeromycota invade roots and colonize the cellular lumen of cortical cells. The establishment of this interaction requires a dedicated molecular-genetic program and a cellular machinery of the plant host. This program is partially shared with the root nodule symbiosis (RNS), which involves prokaryotic partners collectively referred to as rhizobia. Both, AM and RNS are endosymbioses that involve intracellular accommodation of the microbial partner in the cells of the plant host. Since plant cells are surrounded by sturdy cell walls, root penetration and cell invasion requires mechanisms to overcome this barrier while maintaining the cytoplasm of the two partners separate during development of the symbiotic association. Here, we discuss the diverse functions of the cell wall compartment in establishment and functioning of plant symbioses with the emphasis on AM and RNS, and we describe the stages of the AM association between the model organisms Petunia hybrida and Rhizophagus irregularis. PMID:24917869

  13. Biocompatible click chemistry enabled compartment-specific pH measurement inside E. coli.

    PubMed

    Yang, Maiyun; Jalloh, Abubakar S; Wei, Wei; Zhao, Jing; Wu, Peng; Chen, Peng R

    2014-01-01

    Bioorthogonal reactions, especially the Cu(I)-catalysed azide-alkyne cycloaddition, have revolutionized our ability to label and manipulate biomolecules under living conditions. The cytotoxicity of Cu(I) ions, however, has hindered the application of this reaction in the internal space of living cells. By systematically surveying a panel of Cu(I)-stabilizing ligands in promoting protein labelling within the cytoplasm of Escherichia coli, we identify a highly efficient and biocompatible catalyst for intracellular modification of proteins by azide-alkyne cycloaddition. This reaction permits us to conjugate an environment-sensitive fluorophore site specifically onto HdeA, an acid-stress chaperone that adopts pH-dependent conformational changes, in both the periplasm and cytoplasm of E. coli. The resulting protein-fluorophore hybrid pH indicators enable compartment-specific pH measurement to determine the pH gradient across the E. coli cytoplasmic membrane. This construct also allows the measurement of E. coli transmembrane potential, and the determination of the proton motive force across its inner membrane under normal and acid-stress conditions. PMID:25236616

  14. Biocompatible click chemistry enabled compartment-specific pH measurement inside E. coli.

    PubMed

    Yang, Maiyun; Jalloh, Abubakar S; Wei, Wei; Zhao, Jing; Wu, Peng; Chen, Peng R

    2014-09-19

    Bioorthogonal reactions, especially the Cu(I)-catalysed azide-alkyne cycloaddition, have revolutionized our ability to label and manipulate biomolecules under living conditions. The cytotoxicity of Cu(I) ions, however, has hindered the application of this reaction in the internal space of living cells. By systematically surveying a panel of Cu(I)-stabilizing ligands in promoting protein labelling within the cytoplasm of Escherichia coli, we identify a highly efficient and biocompatible catalyst for intracellular modification of proteins by azide-alkyne cycloaddition. This reaction permits us to conjugate an environment-sensitive fluorophore site specifically onto HdeA, an acid-stress chaperone that adopts pH-dependent conformational changes, in both the periplasm and cytoplasm of E. coli. The resulting protein-fluorophore hybrid pH indicators enable compartment-specific pH measurement to determine the pH gradient across the E. coli cytoplasmic membrane. This construct also allows the measurement of E. coli transmembrane potential, and the determination of the proton motive force across its inner membrane under normal and acid-stress conditions.

  15. One probe, two-channel imaging of nuclear and cytosolic compartments with orange and red emissive dyes.

    PubMed

    Pitter, Demar R G; Brown, Adrienne S; Baker, James D; Wilson, James N

    2015-09-28

    Several new DNA-targeting probes that exhibit binding-induced 'turn on' fluorescence are presented. Two of the dyes, orange emissive 1, (E)-4-(4(-4-methylpiperazin-1-yl)phenyl)6-(4-(4-methylpi-perazin-1-yl)styryl)pyrimidin-2-ol), and red emissive 2, (E)-4-(4(-4-methyl-piperazin-1-yl)-phenyl)6-(4-(4-methylpiperazin-1-yl)styryl)-1,3-propanedionato-κO,κO']difluoroborane), are brightly fluorescent when bound to DNA, but are virtually non-fluorescent in aqueous solutions. Confocal fluorescence microscopy of live BT474, MCF7 and HEK293 cells demonstrates that both probes are cell permeable and rapidly accumulated intracellularly into cell nuclei and the cytosol. Taking advantage of their environmental sensitivity, these two pools of fluorophores are readily resolved into separate channels, and thus, a single dye allows two-color imaging of the nuclear and cytosolic compartments. PMID:26257246

  16. Rare times rare: The hyponatremia, rhabdomyolysis, anterior compartment syndrome sequence

    PubMed Central

    Dubin, Ina; Gelber, Moshe

    2016-01-01

    Lesson Primary polydipsia occurs in up to 25% of patients with chronic psychiatric disorders (especially schizophrenia), related to the disease, its treatment or both. Urine output fails to match intake >10 L/day and water intoxication may develop. Rhabdomyolysis is a rare complication of hyponatremia, and an acute anterior compartment syndrome of the leg, an emergency, may be very rarely associated. PMID:27186379

  17. Closeup view if the starboard side of the crew compartment ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Close-up view if the starboard side of the crew compartment mid-deck of the Orbiter Discovery. This is a close up view of the galley for meal preparations. In the center right of the image is stowage lockers that are designated to store meals for the mission. This photograph was taken at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

  18. Closeup view of the reflective insulation protecting the Crew Compartment ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Close-up view of the reflective insulation protecting the Crew Compartment bulkhead, orbiter structure and landing gear housing in the void created by the removal of the Forward Reaction Control System Module from the forward section of the Orbiter Discovery. This image was taken from the service platform in the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

  19. Ruptured Baker's cyst with compartment syndrome: an extremely unusual complication.

    PubMed

    Hamlet, Mark; Galanopoulos, Ilias; Mahale, Avinash; Ashwood, Neil

    2012-12-20

    A 69-year-old man presented with sudden onset of pain with acute tense swelling of his left leg. Initially he was treated empirically with antibiotics for cellulitis while the possibility of deep vein thrombosis was ruled out. His symptoms gradually worsened with progressive distal neurological deficit and increasing pain. Further investigations suggested that he had a ruptured Baker's cyst in the calf with development of compartment syndrome.

  20. [The compartment syndrome--still a threat in traumatology].

    PubMed

    Melichar, J; Horálek, F; Hándl, V; Neumann, C; Smajer, B; Sahely, S; Hanoun, G

    2000-10-25

    Paper presents current opinions on the definition, causes, classification, diagnosis and treatment of the compartment syndrome (CS). The development of CS after the long-bone fractures of the lower extremity and also after the limb operations or trauma without fracture is discussed. The importance of early and correct diagnostics and treatment is also revealed. Authors present several case reports and they stress the importance of early fasciotomy when necessary.

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

    PubMed

    Pinheiro, Ana Alexandra da Costa; Marques, Pedro Miguel Dantas Costa; Sá, Pedro Miguel Gomes; Oliveira, Carolina Fernandes; da Silva, Bruno Pombo Ferreira; de Sousa, Cristina Maria Varino

    2015-01-01

    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.

  2. Bacterial assemblages differ between compartments within the coral holobiont

    NASA Astrophysics Data System (ADS)

    Sweet, M. J.; Croquer, A.; Bythell, J. C.

    2011-03-01

    It is widely accepted that corals are associated with a diverse and host species-specific microbiota, but how they are organized within their hosts remains poorly understood. Previous sampling techniques (blasted coral tissues, coral swabs and milked mucus) may preferentially sample from different compartments such as mucus, tissue and skeleton, or amalgamate them, making comparisons and generalizations between studies difficult. This study characterized bacterial communities of corals with minimal mechanical disruption and contamination from water, air and sediments from three compartments: surface mucus layer (SML), coral tissue and coral skeleton. A novel apparatus (the `snot sucker') was used to separate the SML from tissues and skeleton, and these three compartments were compared to swab samples and milked mucus along with adjacent environmental samples (water column and sediments). Bacterial 16S rRNA gene diversity was significantly different between the various coral compartments and environmental samples (PERMANOVA, F = 6.9, df = 8, P = 0.001), the only exceptions being the complete crushed coral samples and the coral skeleton, which were similar, because the skeleton represents a proportionally large volume and supports a relatively rich microflora. Milked mucus differed significantly from the SML collected with the `snot sucker' and was contaminated with zooxanthellae, suggesting that it may originate at least partially from the gastrovascular cavity rather than the tissue surface. A common method of sampling the SML, surface swabs, produced a bacterial community profile distinct from the SML sampled using our novel apparatus and also showed contamination from coral tissues. Our results indicate that microbial communities are spatially structured within the coral holobiont, and methods used to describe these need to be standardized to allow comparisons between studies.

  3. Compartment fabrication of magneto-responsive Janus microrod particles.

    PubMed

    Lee, Su Yeon; Yang, Shu

    2015-01-31

    Monodispersed magneto-responsive microrod particles of variable magnetic/non-magnetic ratios and chemical compositions are created by compartment fabrication in a single poly(dimethylsiloxane) (PDMS) mold with periodic hole arrays. By labeling the two ends with green and red fluorescent dyes separately, we show that the particles can flip freely and reversibly in a confined geometry under the magnetic field, thereby displaying different patterned colors at the air-water interface.

  4. The pseudo-compartment method for coupling partial differential equation and compartment-based models of diffusion.

    PubMed

    Yates, Christian A; Flegg, Mark B

    2015-05-01

    Spatial reaction-diffusion models have been employed to describe many emergent phenomena in biological systems. The modelling technique most commonly adopted in the literature implements systems of partial differential equations (PDEs), which assumes there are sufficient densities of particles that a continuum approximation is valid. However, owing to recent advances in computational power, the simulation and therefore postulation, of computationally intensive individual-based models has become a popular way to investigate the effects of noise in reaction-diffusion systems in which regions of low copy numbers exist. The specific stochastic models with which we shall be concerned in this manuscript are referred to as 'compartment-based' or 'on-lattice'. These models are characterized by a discretization of the computational domain into a grid/lattice of 'compartments'. Within each compartment, particles are assumed to be well mixed and are permitted to react with other particles within their compartment or to transfer between neighbouring compartments. Stochastic models provide accuracy, but at the cost of significant computational resources. For models that have regions of both low and high concentrations, it is often desirable, for reasons of efficiency, to employ coupled multi-scale modelling paradigms. In this work, we develop two hybrid algorithms in which a PDE in one region of the domain is coupled to a compartment-based model in the other. Rather than attempting to balance average fluxes, our algorithms answer a more fundamental question: 'how are individual particles transported between the vastly different model descriptions?' First, we present an algorithm derived by carefully redefining the continuous PDE concentration as a probability distribution. While this first algorithm shows very strong convergence to analytical solutions of test problems, it can be cumbersome to simulate. Our second algorithm is a simplified and more efficient implementation of

  5. Stochastic resonance in an intracellular genetic perceptron

    NASA Astrophysics Data System (ADS)

    Bates, Russell; Blyuss, Oleg; Zaikin, Alexey

    2014-03-01

    Intracellular genetic networks are more intelligent than was first assumed due to their ability to learn. One of the manifestations of this intelligence is the ability to learn associations of two stimuli within gene-regulating circuitry: Hebbian-type learning within the cellular life. However, gene expression is an intrinsically noisy process; hence, we investigate the effect of intrinsic and extrinsic noise on this kind of intracellular intelligence. We report a stochastic resonance in an intracellular associative genetic perceptron, a noise-induced phenomenon, which manifests itself in noise-induced increase of response in efficiency after the learning event under the conditions of optimal stochasticity.

  6. Visualization of Intracellular Tyrosinase Activity in vitro

    PubMed Central

    Setty, Subba Rao Gangi

    2016-01-01

    Melanocytes produce the melanin pigments in melanosomes and these organelles protect the skin against harmful ultraviolet rays. Tyrosinase is the key cuproenzyme which initiates the pigment synthesis using its substrate amino acid tyrosine or L-DOPA (L-3, 4-dihydroxyphenylalanine). Moreover, the activity of tyrosinase directly correlates to the cellular pigmentation. Defects in tyrosinase transport to melanosomes or mutations in the enzyme or reduced intracellular copper levels results in loss of tyrosinase activity in melanosomes, commonly observed in albinism. Here, we described a method to detect the intracellular activity of tyrosinase in mouse melanocytes. This protocol will visualize the active tyrosinase present in the intracellular vesicles or organelles including melanosomes. PMID:27231711

  7. Spatial aspects of intracellular information processing.

    PubMed

    Kinkhabwala, Ali; Bastiaens, Philippe I H

    2010-02-01

    The computational properties of intracellular biochemical networks, for which the cell is assumed to be a 'well-mixed' reactor, have already been widely characterized. What has so far not received systematic treatment is the important role of space in many intracellular computations. Spatial network computations can be divided into two broad categories: those required for essential spatial processes (e.g. polarization, chemotaxis, division, and development) and those for which space is simply used as an extra dimension to expand the computational power of the network. Several pertinent recent examples of each category are discussed that illustrate the often conceptually subtle role of space in the processing of intracellular information. PMID:20096560

  8. Opioid overdose with gluteal compartment syndrome and acute peripheral neuropathy

    PubMed Central

    Adrish, Muhammad; Duncalf, Richard; Diaz-Fuentes, Gilda; Venkatram, Sindhaghatta

    2014-01-01

    Patient: Male, 42 Final Diagnosis: Gluteal compartment syndrome • acute peripheral nauropathy Symptoms: — Medication: — Clinical Procedure: — Specialty: Critical Care Medicine Objective: Management of emergency care Background: Heroin addiction is common, with an estimated 3.7 million Americans reporting to have used it at some point in their lives. Complications of opiate overdose include infection, rhabdomyolysis, respiratory depression and central or peripheral nervous system neurological complications. Conclusions: We present a 42-year-old male admitted after heroin use with heroin-related peripheral nervous system complication preceded by an acute gluteal compartment syndrome and severe rhabdomyolysis. Case Report: Early diagnosis and surgical intervention of the compartment syndrome can lead to full recovery while any delay in management can be devastating and can lead to permanent disability. The presence of peripheral nervous system injuries may portend a poor prognosis and can also lead to long term disability. Careful neurological evaluation for signs and symptoms of peripheral nervous system injuries is of paramount importance, as these may be absent at presentation in patients with opioid overdose. There is a potential risk of delaying a necessary treatment like fasciotomy in these patients by falsely attributing clinical symptoms to a preexisting neuropathy. Early EMG and nerve conduction studies should be considered when the etiology of underlying neurological weakness is unclear. PMID:24459539

  9. Bacterial Translocation – Impact on the Adipocyte Compartment

    PubMed Central

    Kruis, Tassilo; Batra, Arvind; Siegmund, Britta

    2013-01-01

    Over the last decade it became broadly recognized that adipokines and thus the fat tissue compartment exert a regulatory function on the immune system. Our own group described the pro-inflammatory function of the adipokine leptin within intestinal inflammation in a variety of animal models. Following-up on this initial work, the aim was to reveal stimuli and mechanisms involved in the activation of the fat tissue compartment and the subsequent release of adipokines and other mediators paralleled by the infiltration of immune cells. This review will summarize the current literature on the possible role of the mesenteric fat tissue in intestinal inflammation with a focus on Crohn’s disease (CD). CD is of particular interest in this context since the transmural intestinal inflammation has been associated with a characteristic hypertrophy of the mesenteric fat, a phenomenon called “creeping fat.” The review will address three consecutive questions: (i) What is inducing adipocyte activation, (ii) which factors are released after activation and what are the consequences for the local fat tissue compartment and infiltrating cells; (iii) do the answers generated before allow for an explanation of the role of the mesenteric fat tissue within intestinal inflammation? With this review we will provide a working model indicating a close interaction in between bacterial translocation, activation of the adipocytes, and subsequent direction of the infiltrating immune cells. In summary, the models system mesenteric fat indicates a unique way how adipocytes can directly interact with the immune system. PMID:24432024

  10. Design/Development of Spacecraft and Module Crew Compartments

    NASA Technical Reports Server (NTRS)

    Goodman, Jerry R.

    2010-01-01

    This slide presentation reviews the design and development of crew compartments for spacecraft and for modules. The Crew Compartment or Crew Station is defined as the spacecraft interior and all other areas the crewman interfaces inside the cabin, or may potentially interface.It uses examples from all of the human rated spacecraft. It includes information about the process, significant drivers for the design, habitability, definitions of models, mockups, prototypes and trainers, including pictures of each stage in the development from Apollo, pictures of the space shuttle trainers, and International Space Station trainers. It further reviews the size and shape of the Space Shuttle orbiter crew compartment, and the Apollo command module and the lunar module. It also has a chart which reviews the International Space Station (ISS) internal volume by stage. The placement and use of windows is also discussed. Interestingly according to the table presented, the number 1 rated piece of equipment for recreation was viewing windows. The design of crew positions and restraints, crew translation aids and hardware restraints is shown with views of the restraints and handholds used from the Apollo program through the ISS.

  11. [Compartment pressure of the anterior tibial area in jogging].

    PubMed

    Jerosch, J; Geske, B; Castro, W H; Hille, E

    1989-01-01

    31 healthy persons had to run on a treadmill under defined conditions at a constant speed of 8 km/h. Pressure in the anterior flexor-muscles compartment was measured regulary in time before, during and after running; the size of the compartment was documented by sonography. The measured pressure was attached to the respective compartment size. The runners were divided into three groups based on characteristic pressure-courses: the normal-type with average values below 50 mmHg, the indifference-type with a distinctly higher pressure than 50 mmHg and the risk-type with values more than 70 mmHg. A correlation between exercise-pressure and time of post-exercising decrease of pressure was found. While the normal type reached the starting pressure within 6 minutes the indifference and risk type didn't succeed in decreasing after this period of time. No change of compartmental size was measured while the pressure increased on exertion. PMID:2655333

  12. The statolith compartment in Chara rhizoids contains carbohydrate and protein

    NASA Technical Reports Server (NTRS)

    Wang-Cahill, F.; Kiss, J. Z.

    1995-01-01

    In contrast to higher plants, the alga Chara has rhizoids with single membrane-bound compartments that function as statoliths in gravity perception. Previous work has demonstrated that these statoliths contain barium sulfate crystals. In this study, we show that statoliths in Chara rhizoids react with a Coomassie Brilliant Blue cytochemical stain for proteins. While statoliths did not react with silver methenamine carbohydrate cytochemistry, the monoclonal antibody CCRC-M2, which is against a carbohydrate (sycamore-maple rhamnogalacturonan I), labeled the statolith compartment. These results demonstrate that in addition to barium sulfate, statoliths in Chara rhizoids have an organic matrix that consists of protein and carbohydrate moieties. Since the statoliths were silver methenamine negative, the carbohydrate in this compartment could be a 3-linked polysaccharide. CCRC-M2 also labeled Golgi cisternae, Golgi-associated vesicles, apical vesicles, and cell walls in the rhizoids. The specificity of CCRC-M2 immunolabeling was verified by several control experiments, including the demonstration that labeling was abolished when the antibody was preabsorbed with its antigen. Since in this and a previous study (John Z. Kiss and L. Andrew Staehelin, American Journal of Botany 80: 273-282, 1993) antibodies against higher plant carbohydrates crossreacted with cell walls of Chara in a specific manner, Characean algae may be a useful model system in biochemical and molecular studies of cell walls.

  13. Engineered Protein Nano-Compartments for Targeted Enzyme Localization

    PubMed Central

    Choudhary, Swati; Quin, Maureen B.; Sanders, Mark A.; Johnson, Ethan T.; Schmidt-Dannert, Claudia

    2012-01-01

    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. PMID:22428024

  14. View of bulkhead mounted steam powered windlass in compartment B126 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of bulkhead mounted steam powered windlass in compartment B-126 used for servicng boiler room compartments B-3 and B-4. (052A) - USS Olympia, Penn's Landing, 211 South Columbus Boulevard, Philadelphia, Philadelphia County, PA

  15. 19 CFR 148.21 - Opening of baggage, compartments, or vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... the right to open and examine all baggage, compartments and vehicles brought into the United States... baggage, compartment or vehicle first. If the owner or his agent is unavailable or refuses to open...

  16. View of compartment D16, passing room; shaft and universal joints ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of compartment D-16, passing room; shaft and universal joints at top of photograph transmit control forces to steering unit in compartment d-23. (p62) - USS Olympia, Penn's Landing, 211 South Columbus Boulevard, Philadelphia, Philadelphia County, PA

  17. Keeping active channels in their place: membrane phosphoinositides regulate TRPM channel activity in a compartment-selective manner.

    PubMed

    Braun, Andrew P

    2012-01-01

    We have long appreciated that the controlled movement of ions and solutes across the cell surface or plasma membrane affects every aspect of cell function, ranging from membrane excitability to metabolism to secretion, and is also critical for the long-term maintenance of cell viability. Studies examining these physiological transport processes have revealed a vast array of ion channels, transporters and ATPase-driven pumps that underlie these transmembrane ionic movements and how acquired or genetic disruption of these processes are linked to disease. More recently, it has become evident that the ongoing function of intracellular organelles and subcellular compartments also depends heavily on the controlled movement of ions to establish distinct pH or ionic environments. However, limited experimental access to these subcellular domains/structures has hampered scientific progress in this area, due in large part to the difficulty of applying proven functional assays, such as patch clamp and radiotracer methodologies, to these specialized membrane locations. Using both functional and immune-labeling assays, we now know that the types and complement of channels, transporters and pumps located within intracellular membranes and organelles often differ from those present on the plasma membrane. Moreover, it appears that this differential distribution is due to the presence of discrete tags/signals present within these transport proteins that dictate their sorting/trafficking to spatially discrete membrane compartments, where they may also interact with scaffolding proteins that help maintain their localization. Such targeting signals may thus operate in a manner analogous to the way a postal code is used to direct the delivery of a letter. PMID:23151432

  18. Community structure at two compartments of a disturbed mangrove forests at Pulau Langkawi

    NASA Astrophysics Data System (ADS)

    Norilani, W. I. Wan; Juliana, W. A. Wan; Salam, Muhamad Razali; Latiff, A.

    2014-09-01

    A study on floristic composition and estimation of above ground biomass of trees was carried out in two areas of disturbed mangroves at Kisap Forest Reserve, Pulau Langkawi. Two compartments that were selected was based on the different types of disturbances, i.e. compartment 5 (C5) was disrupted by human harvesting activities of mangrove trees for charcoal production, while compartment 7 (C7) was naturally disturbed from lightning strikes. In C5, a total of 1,217 trees measuring 1 cm DBH and above were enumerated in the plots of 0.25 ha which included 7 species and 5 genera in 3 families, i.e. Rhizophoraceae, Meliaceae and Avicenniaceae. In C7, a total of 390 individual trees of 8 species, 5 genera and 3 families were recorded. The three families recorded in C7 were also common in C5. Rhizophoraceae was recorded as the family with highest density in both compartments. Ceriops tagal had the highest density in C5, while Rhizophora apiculata was the most prominent species in the C7. Total basal area that represents tree coverage showed C5 had a value of 7.767 m2/ha with C. tagal as the major contributor at 5.022m2/ha. Total coverage in C7 was 18.184 m2/ha that was mostly contributed by R. apiculata at 11.135 m2/ha. Ceriops tagal (22.41 t/ha) and R. apiculata (111.75 t/ha), were the main contributors to the total biomass in C5 (37.34 t/ha) and C7 (162.29 t/ha), respectively. The distribution of individuals of six tree size classes in C7 was homogenous compared to that of C5, which had more saplings. In this study, the total biomass indicated that anthropogenic activities resulted in lower productivity of forest compared to natural disturbance. Therefore, conservation efforts of mangrove forest should be enhance in the management of mangrove forest in Pulau Langkawi.

  19. Prognostic impact of a compartment-specific angiogenic marker profile in patients with pancreatic cancer

    PubMed Central

    Musso, Gabriel; Halama, Niels; Keim, Sophia; Mazzone, Massimiliano; Lasitschka, Felix; Pecqueux, Mathieu; Klupp, Fee; Schmidt, Thomas; Rahbari, Nuh; Schölch, Sebastian; Pilarsky, Christian; Ulrich, Alexis; Schneider, Martin; Weitz, Juergen; Koch, Moritz

    2014-01-01

    Pancreatic cancer consists of a heterogenous bulk of tumor cells and stroma cells which contribute to tumor progression by releasing angiogenic factors. Those factors can be detected as circulating serum factors. We performed a compartment-specific analysis of tumor-derived and stroma-derived angiogenic factors to identify biomarkers and molecular targets for the treatment of pancreatic cancer. Kryo-frozen tissue from primary ductal adenocarcinomas (n = 51) was laser-microdissected to isolate tumor and stroma tissue. Expression of 17 angiogenic factors (angiopoietin-2, follistatin, GCSF, HGF, interleukin-8, leptin, PDGF-BB, PECAM-1, VEGF, matrix metalloproteinase -1, -2, -3, -7, -9, -10, -12, and -13) was analyzed using a multiplex elisa assay for tissue-derived proteins and corresponding serum. Our study reveals a compartment-specific expression profile for several angiogenic factors and matrix metalloproteinases. ROC analysis of corresponding serum samples reveals MMP-7 and MMP-12 as strong classifiers for the diagnosis of patients with pancreatic cancer vs. healthy control donors. High expression of tumor-derived PDGF-BB and MMP-1 correlates with prolonged survival in univariate and multivariate analysis. In conclusion, a distinct expression patterns for angiogenic cytokines and MMPs in pancreatic cancer and surrounding stroma may implicate them as novel targets for cancer treatment. Tumor-derived PDGF-BB and MMP-1 are significant and independent prognostic markers for poor survival. PMID:25483099

  20. Effect of center of pressure modulation on knee adduction moment in medial compartment knee osteoarthritis.

    PubMed

    Haim, Amir; Wolf, Alon; Rubin, Guy; Genis, Yulya; Khoury, Mona; Rozen, Nimrod

    2011-11-01

    The knee adduction moment (KAM) provides a major contribution to the elevated load in the medial compartment of the knee. An abnormally high KAM has been linked with the progression of knee osteoarthritis (OA). Footwear-generated biomechanical manipulations reduce the magnitude of this moment by conveying a more laterally shifted trajectory of the foot's center of pressure (COP), reducing the distance between the ground reaction force and the center of the knee joint, thus lowering the magnitude of the torque. We sought to examine the outcome of a COP shift in a cohort of female patients suffering from medial knee OA. Twenty-two female patients suffering from medial compartment knee OA underwent successive gait analysis testing and direct pedobarographic examination of the COP trajectory with a foot-worn biomechanical device allowing controlled manipulation of the COP. Modulation of the COP coronal trajectory from medial to lateral offset resulted in a significant reduction of the KAM. This trend was demonstrated in subjects with mild-to-moderate OA and in patients suffering from severe stages of the disease. Our results indicate that controlled manipulation of knee coronal kinetics in individuals suffering from medial knee OA can be facilitated by customized COP modification.