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Sample records for spg13 compromises chaperonin

  1. Chaperonins.

    PubMed Central

    Ranson, N A; White, H E; Saibil, H R

    1998-01-01

    The molecular chaperones are a diverse set of protein families required for the correct folding, transport and degradation of other proteins in vivo. There has been great progress in understanding the structure and mechanism of action of the chaperonin family, exemplified by Escherichia coli GroEL. The chaperonins are large, double-ring oligomeric proteins that act as containers for the folding of other protein subunits. Together with its co-protein GroES, GroEL binds non-native polypeptides and facilitates their refolding in an ATP-dependent manner. The action of the ATPase cycle causes the substrate-binding surface of GroEL to alternate in character between hydrophobic (binding/unfolding) and hydrophilic (release/folding). ATP binding initiates a series of dramatic conformational changes that bury the substrate-binding sites, lowering the affinity for non-native polypeptide. In the presence of ATP, GroES binds to GroEL, forming a large chamber that encapsulates substrate proteins for folding. For proteins whose folding is absolutely dependent on the full GroE system, ATP binding (but not hydrolysis) in the encapsulating ring is needed to initiate protein folding. Similarly, ATP binding, but not hydrolysis, in the opposite GroEL ring is needed to release GroES, thus opening the chamber. If the released substrate protein is still not correctly folded, it will go through another round of interaction with GroEL. PMID:9657960

  2. How do chaperonins fold protein?

    PubMed Central

    Motojima, Fumihiro

    2015-01-01

    Protein folding is a biological process that is essential for the proper functioning of proteins in all living organisms. In cells, many proteins require the assistance of molecular chaperones for their folding. Chaperonins belong to a class of molecular chaperones that have been extensively studied. However, the mechanism by which a chaperonin mediates the folding of proteins is still controversial. Denatured proteins are folded in the closed chaperonin cage, leading to the assumption that denatured proteins are completely encapsulated inside the chaperonin cage. In contrast to the assumption, we recently found that denatured protein interacts with hydrophobic residues at the subunit interfaces of the chaperonin, and partially protrude out of the cage. In this review, we will explain our recent results and introduce our model for the mechanism by which chaperonins accelerate protein folding, in view of recent findings.

  3. Chaperonin filaments: The archael cytoskeleton

    SciTech Connect

    Trent, J.D.; Kagawa, H.K.; Yaoi, Takuro; Olle, E.; Zaluzec, N.J.

    1997-08-01

    Chaperonins are multi-subunit double-ring complexed composed of 60-kDa proteins that are believed to mediate protein folding in vivo. The chaperonins in the hyperthermophilic archaeon Sulfolobus shibatae are composed of the organism`s two most abundant proteins, which represent 4% of its total protein and have an intracellular concentration of {ge} 3.0 mg/ml. At concentrations of 1.0 mg/ml, purified chaperonin proteins aggregate to form ordered filaments. Filament formation, which requires Mg{sup ++} and nucleotide binding (not hydrolysis), occurs at physiological temperatures under conditions suggesting filaments may exist in vivo. If the estimated 4,600 chaperonins per cell, formed filaments in vivo, they could create a matrix of filaments that would span the diameter of an average S. shibatae cell 100 times. Direct observations of unfixed, minimally treated cells by intermediate voltage electron microscopy (300 kV) revealed an intracellular network of filaments that resembles chaperonin filaments produced in vitro. The hypothesis that the intracellular network contains chaperonins is supported by immunogold analyses. The authors propose that chaperonin activity may be regulated in vivo by filament formation and that chaperonin filaments may serve a cytoskeleton-like function in archaea and perhaps in other prokaryotes.

  4. The complexity of chloroplast chaperonins.

    PubMed

    Vitlin Gruber, Anna; Nisemblat, Shahar; Azem, Abdussalam; Weiss, Celeste

    2013-12-01

    Type I chaperonins are large oligomeric protein ensembles that are involved in the folding and assembly of other proteins. Chloroplast chaperonins and co-chaperonins exist in multiple copies of two distinct isoforms that can combine to form a range of labile oligomeric structures. This complex system increases the potential number of chaperonin substrates and possibilities for regulation. The incorporation of unique subunits into the oligomer can modify substrate specificity. Some subunits are upregulated in response to heat shock and some show organ-specific expression, whereas others possess additional functions that are unrelated to their role in protein folding. Accumulating evidence suggests that specific subunits have distinct roles in biogenesis of ribulose-1,5-bisphosphate carboxylase oxygenase (Rubisco). PMID:24035661

  5. Allosteric Mechanisms in Chaperonin Machines.

    PubMed

    Gruber, Ranit; Horovitz, Amnon

    2016-06-01

    Chaperonins are nanomachines that facilitate protein folding by undergoing energy (ATP)-dependent movements that are coordinated in time and space owing to complex allosteric regulation. They consist of two back-to-back stacked oligomeric rings with a cavity at each end where protein substrate folding can take place. Here, we focus on the GroEL/GroES chaperonin system from Escherichia coli and, to a lesser extent, on the more poorly characterized eukaryotic chaperonin CCT/TRiC. We describe their various functional (allosteric) states and how they are affected by substrates and allosteric effectors that include ATP, ADP, nonfolded protein substrates, potassium ions, and GroES (in the case of GroEL). We also discuss the pathways of intra- and inter-ring allosteric communication by which they interconvert and the coupling between allosteric transitions and protein folding reactions. PMID:26726755

  6. Chaperonin filaments: The archaeal cytoskeleton?

    PubMed Central

    Trent, Jonathan D.; Kagawa, Hiromi K.; Yaoi, Takuro; Olle, Eric; Zaluzec, Nestor J.

    1997-01-01

    Chaperonins are high molecular mass double-ring structures composed of 60-kDa protein subunits. In the hyperthermophilic archaeon Sulfolobus shibatae the two chaperonin proteins represent ≈4% of its total protein and have a combined intracellular concentration of >30 mg/ml. At concentrations ≥ 0.5 mg/ml purified chaperonins form filaments in the presence of Mg2+ and nucleotides. Filament formation requires nucleotide binding (not hydrolysis), and occurs at physiological temperatures in biologically relevant buffers, including a buffer made from cell extracts. These observations suggest that chaperonin filaments may exist in vivo and the estimated 4600 chaperonins per cell suggest that such filaments could form an extensive cytostructure. We observed filamentous structures in unfixed, uranyl-acetate-stained S. shibatae cells, which resemble the chaperonin filaments in size and appearance. ImmunoGold (Janssen) labeling using chaperonin antibodies indicated that many chaperonins are associated with insoluble cellular structures and these structures appear to be filamentous in some areas, although they could not be uranyl-acetate-stained. The existence of chaperonin filaments in vivo suggests a mechanism whereby their protein-folding activities can be regulated. More generally, the filaments themselves may play a cytoskeletal role in Archaea. PMID:9144246

  7. Ordered biological nanostructures formed from chaperonin polypeptides

    NASA Technical Reports Server (NTRS)

    Trent, Jonathan D. (Inventor); McMillan, R. Andrew (Inventor); Kagawa, Hiromi (Inventor); Paavola, Chad D. (Inventor)

    2010-01-01

    The following application relates to nanotemplates, nanostructures, nanoarrays and nanodevices formed from wild-type and mutated chaperonin polypeptides, methods of producing such compositions, methods of using such compositions and particular chaperonin polypeptides that can be utilized in producing such compositions.

  8. Ordered Nanostructures Made Using Chaperonin Polypeptides

    NASA Technical Reports Server (NTRS)

    Trent, Jonathan; McMillan, Robert; Paavola, Chad; Mogul, Rakesh; Kagawa, Hiromi

    2004-01-01

    A recently invented method of fabricating periodic or otherwise ordered nanostructures involves the use of chaperonin polypeptides. The method is intended to serve as a potentially superior and less expensive alternative to conventional lithographic methods for use in the patterning steps of the fabrication of diverse objects characterized by features of the order of nanometers. Typical examples of such objects include arrays of quantum dots that would serve as the functional building blocks of future advanced electronic and photonic devices. A chaperonin is a double-ring protein structure having a molecular weight of about 60 plus or minus 5 kilodaltons. In nature, chaperonins are ubiquitous, essential, subcellular structures. Each natural chaperonin molecule comprises 14, 16, or 18 protein subunits, arranged as two stacked rings approximately 16 to 18 nm tall by approximately 15 to 17 nm wide, the exact dimensions depending on the biological species in which it originates. The natural role of chaperonins is unknown, but they are believed to aid in the correct folding of other proteins, by enclosing unfolded proteins and preventing nonspecific aggregation during assembly. What makes chaperonins useful for the purpose of the present method is that under the proper conditions, chaperonin rings assemble themselves into higher-order structures. This method exploits such higher-order structures to define nanoscale devices. The higher-order structures are tailored partly by choice of chemical and physical conditions for assembly and partly by using chaperonins that have been mutated. The mutations are made by established biochemical techniques. The assembly of chaperonin polypeptides into such structures as rings, tubes, filaments, and sheets (two-dimensional crystals) can be regulated chemically. Rings, tubes, and filaments of some chaperonin polypeptides can, for example, function as nano vessels if they are able to absorb, retain, protect, and release gases or

  9. Chaperonin-mediated Protein Folding

    PubMed Central

    Horwich, Arthur L.

    2013-01-01

    We have been studying chaperonins these past twenty years through an initial discovery of an action in protein folding, analysis of structure, and elucidation of mechanism. Some of the highlights of these studies were presented recently upon sharing the honor of the 2013 Herbert Tabor Award with my early collaborator, Ulrich Hartl, at the annual meeting of the American Society for Biochemistry and Molecular Biology in Boston. Here, some of the major findings are recounted, particularly recognizing my collaborators, describing how I met them and how our great times together propelled our thinking and experiments. PMID:23803606

  10. Crystal structure of the human mitochondrial chaperonin symmetrical football complex.

    PubMed

    Nisemblat, Shahar; Yaniv, Oren; Parnas, Avital; Frolow, Felix; Azem, Abdussalam

    2015-05-12

    Human mitochondria harbor a single type I chaperonin system that is generally thought to function via a unique single-ring intermediate. To date, no crystal structure has been published for any mammalian type I chaperonin complex. In this study, we describe the crystal structure of a football-shaped, double-ring human mitochondrial chaperonin complex at 3.15 Å, which is a novel intermediate, likely representing the complex in an early stage of dissociation. Interestingly, the mitochondrial chaperonin was captured in a state that exhibits subunit asymmetry within the rings and nucleotide symmetry between the rings. Moreover, the chaperonin tetradecamers show a different interring subunit arrangement when compared to GroEL. Our findings suggest that the mitochondrial chaperonins use a mechanism that is distinct from the mechanism of the well-studied Escherichia coli system. PMID:25918392

  11. Crystal structure of the human mitochondrial chaperonin symmetrical football complex

    PubMed Central

    Nisemblat, Shahar; Yaniv, Oren; Parnas, Avital; Frolow, Felix; Azem, Abdussalam

    2015-01-01

    Human mitochondria harbor a single type I chaperonin system that is generally thought to function via a unique single-ring intermediate. To date, no crystal structure has been published for any mammalian type I chaperonin complex. In this study, we describe the crystal structure of a football-shaped, double-ring human mitochondrial chaperonin complex at 3.15 Å, which is a novel intermediate, likely representing the complex in an early stage of dissociation. Interestingly, the mitochondrial chaperonin was captured in a state that exhibits subunit asymmetry within the rings and nucleotide symmetry between the rings. Moreover, the chaperonin tetradecamers show a different interring subunit arrangement when compared to GroEL. Our findings suggest that the mitochondrial chaperonins use a mechanism that is distinct from the mechanism of the well-studied Escherichia coli system. PMID:25918392

  12. Mycobacterium tuberculosis expresses two chaperonin-60 homologs.

    PubMed Central

    Kong, T H; Coates, A R; Butcher, P D; Hickman, C J; Shinnick, T M

    1993-01-01

    A 65-kDa protein and a 10-kDa protein are two of the more strongly immunoreactive components of Mycobacterium tuberculosis, the causative agent of tuberculosis. The 65-kDa antigen has homology with members of the GroEL or chaperonin-60 (Cpn60) family of heat shock proteins. The 10-kDa antigen has homology with the GroES or chaperonin-10 family of heat shock proteins. These two proteins are encoded by separate genes in M. tuberculosis. The studies reported here reveal that M. tuberculosis contains a second Cpn60 homolog located 98 bp downstream of the 10-kDa antigen gene. The second Cpn60 homolog (Cpn60-1) displays 61% amino acid sequence identity with the 65-kDa antigen (Cpn60-2) and 53% and 41% identity with the Escherichia coli GroEL protein and the human P60 protein, respectively. Primer-extension analysis revealed that transcription starts 29 bp upstream of the translation start of the Cpn60-1 homolog and protein purification studies indicate that the cpn60-1 gene is expressed as an approximately 60-kDa polypeptide. Images Fig. 3 Fig. 5 PMID:7681982

  13. The Molecular Basis of Hyperthermophily: The Role of HSP60/Chaperonins In Vivo

    NASA Technical Reports Server (NTRS)

    Kagawa, Hiromi

    2002-01-01

    In this study, we aim to understand how S. shibatae copes with high temperatures. In particular, we investigated the role of the 60 kDa heat shock protein (HSP60 or chaperonin) with the hypothesis that chaperonin stabilizes the cell membrane under stressful conditions. To prove the hypothesis, this year two questions were addressed: (1) Is the chaperonin localized in the cytoplasm or on the cell membrane? (2) Does the chaperonin show affinity to lipid in vivo? In addition to those, we intensively studied newly discovered chaperonin-related protein, gamma, to understand how it influenced the function of the other components of chaperonin and how their combined activities contributed to hyperthermophily.

  14. Ordered nanoparticle arrays formed on engineered chaperonin protein templates.

    SciTech Connect

    McMillan, R. A.; Paavola, C. D.; Howard, J.; Chan, S. L.; Zaluzec, N. J.; Trent, J. D.; Materials Science Division; NASA Ames Research Center; SETI Inst.

    2002-12-01

    Traditional methods for fabricating nanoscale arrays are usually based on lithographic techniques. Alternative new approaches rely on the use of nanoscale templates made of synthetic or biological materials. Some proteins, for example, have been used to form ordered two-dimensional arrays. Here, we fabricated nanoscale ordered arrays of metal and semiconductor quantum dots by binding preformed nanoparticles onto crystalline protein templates made from genetically engineered hollow double-ring structures called chaperonins. Using structural information as a guide, a thermostable recombinant chaperonin subunit was modified to assemble into chaperonins with either 3 nm or 9 nm apical pores surrounded by chemically reactive thiols. These engineered chaperonins were crystallized into two-dimensional templates up to 20 m in diameter. The periodic solvent-exposed thiols within these crystalline templates were used to size-selectively bind and organize either gold (1.4, 5 or 10nm) or CdSe-ZnS semiconductor (4.5 nm) quantum dots into arrays. The order within the arrays was defined by the lattice of the underlying protein crystal. By combining the self-assembling properties of chaperonins with mutations guided by structural modelling, we demonstrate that quantum dots can be manipulated using modified chaperonins and organized into arrays for use in next-generation electronic and photonic devices.

  15. Ordered nanoparticle arrays formed on engineered chaperonin protein templates

    NASA Technical Reports Server (NTRS)

    McMillan, R. Andrew; Paavola, Chad D.; Howard, Jeanie; Chan, Suzanne L.; Zaluzec, Nestor J.; Trent, Jonathan D.

    2002-01-01

    Traditional methods for fabricating nanoscale arrays are usually based on lithographic techniques. Alternative new approaches rely on the use of nanoscale templates made of synthetic or biological materials. Some proteins, for example, have been used to form ordered two-dimensional arrays. Here, we fabricated nanoscale ordered arrays of metal and semiconductor quantum dots by binding preformed nanoparticles onto crystalline protein templates made from genetically engineered hollow double-ring structures called chaperonins. Using structural information as a guide, a thermostable recombinant chaperonin subunit was modified to assemble into chaperonins with either 3 nm or 9 nm apical pores surrounded by chemically reactive thiols. These engineered chaperonins were crystallized into two-dimensional templates up to 20 microm in diameter. The periodic solvent-exposed thiols within these crystalline templates were used to size-selectively bind and organize either gold (1.4, 5 or 10nm) or CdSe-ZnS semiconductor (4.5 nm) quantum dots into arrays. The order within the arrays was defined by the lattice of the underlying protein crystal. By combining the self-assembling properties of chaperonins with mutations guided by structural modelling, we demonstrate that quantum dots can be manipulated using modified chaperonins and organized into arrays for use in next-generation electronic and photonic devices.

  16. Archaeal-like chaperonins in bacteria.

    PubMed

    Techtmann, Stephen M; Robb, Frank T

    2010-11-23

    Chaperonins (CPN) are ubiquitous oligomeric protein machines that mediate the ATP-dependent folding of polypeptide chains. These chaperones have not only been assigned stress response and normal housekeeping functions but also have a role in certain human disease states. A longstanding convention divides CPNs into two groups that share many conserved sequence motifs but differ in both structure and distribution. Group I complexes are the well known GroEL/ES heat-shock proteins in bacteria, that also occur in some species of mesophilic archaea and in the endosymbiotic organelles of eukaryotes. Group II CPNs are found only in the cytosol of archaea and eukaryotes. Here we report a third, divergent group of CPNs found in several species of bacteria. We propose to name these Group III CPNs because of their distant relatedness to both Group I and II CPNs as well as their unique genomic context, within the hsp70 operon. The prototype Group III CPN, Carboxydothermus hydrogenoformans chaperonin (Ch-CPN), is able to refold denatured proteins in an ATP-dependent manner and is structurally similar to the Group II CPNs, forming a 16-mer with each subunit contributing to a flexible lid domain. The Group III CPN represent a divergent group of bacterial CPNs distinct from the GroEL/ES CPN found in all bacteria. The Group III lineage may represent an ancient horizontal gene transfer from an archaeon into an early Firmicute lineage. An analysis of their functional and structural characteristics may provide important insights into the early history of this ubiquitous family of proteins. PMID:21057109

  17. Chaperonin Polymers in Archaea: The Cytoskeleton of Prokaryotes?

    DOE R&D Accomplishments Database

    Trent, J. D.; Kagawa, H. K.; Zaluzec, N. J.

    1997-07-01

    Chaperonins are protein complexes that play a critical role in folding nascent polypeptides under normal conditions and refolding damaged proteins under stress conditions. In all organisms these complexes are composed of evolutionarily conserved 60-kDa proteins arranged in double-ring structures with between 7 and 9 protein subunits per ring. These double ring structures are assumed to be the functional units in vivo, although they have never been observed inside cells. Here the authors show that the purified chaperonin from the hyperthermophilic archaeon Sulfolobus shibatae, which is closely related to chaperonins in eukaryotes, has a double ring structure at low concentrations (0.1 mg/ml), but at more physiological concentrations, the rings stack end to end to form polymers. The polymers are stable at physiological temperatures (75 C) and closely resemble structures observed inside unfixed S. shibatae cells. The authors suggest that in vivo chaperonin activity may be regulated by polymerization and that chaperonin polymers may act as a cytoskeleton-like structure in archaea and bacteria.

  18. The Mechanism and Function of Group II Chaperonins.

    PubMed

    Lopez, Tom; Dalton, Kevin; Frydman, Judith

    2015-09-11

    Protein folding in the cell requires the assistance of enzymes collectively called chaperones. Among these, the chaperonins are 1-MDa ring-shaped oligomeric complexes that bind unfolded polypeptides and promote their folding within an isolated chamber in an ATP-dependent manner. Group II chaperonins, found in archaea and eukaryotes, contain a built-in lid that opens and closes over the central chamber. In eukaryotes, the chaperonin TRiC/CCT is hetero-oligomeric, consisting of two stacked rings of eight paralogous subunits each. TRiC facilitates folding of approximately 10% of the eukaryotic proteome, including many cytoskeletal components and cell cycle regulators. Folding of many cellular substrates of TRiC cannot be assisted by any other chaperone. A complete structural and mechanistic understanding of this highly conserved and essential chaperonin remains elusive. However, recent work is beginning to shed light on key aspects of chaperonin function and how their unique properties underlie their contribution to maintaining cellular proteostasis. PMID:25936650

  19. Chaperonin polymers in archaea: The cytoskeleton of prokaryotes?

    SciTech Connect

    Trent, J.D.; Kagawa, H.K.; Zaluzec, N.J.

    1997-07-01

    Chaperonins are protein complexes that play a critical role in folding nascent polypeptides under normal conditions and refolding damaged proteins under stress conditions. In all organisms these complexes are composed of evolutionarily conserved 60-kDa proteins arranged in double-ring structures with between 7 and 9 protein subunits per ring. These double ring structures are assumed to be the functional units in vivo, although they have never been observed inside cells. Here the authors show that the purified chaperonin from the hyperthermophilic archaeon Sulfolobus shibatae, which is closely related to chaperonins in eukaryotes, has a double ring structure at low concentrations (0.1 mg/ml), but at more physiological concentrations, the rings stack end to end to form polymers. The polymers are stable at physiological temperatures (75 C) and closely resemble structures observed inside unfixed S. shibatae cells. The authors suggest that in vivo chaperonin activity may be regulated by polymerization and that chaperonin polymers may act as a cytoskeleton-like structure in archaea and bacteria.

  20. Cpn20: siamese twins of the chaperonin world.

    PubMed

    Weiss, Celeste; Bonshtien, Anat; Farchi-Pisanty, Odelia; Vitlin, Anna; Azem, Abdussalam

    2009-02-01

    The chloroplast cpn20 protein is a functional homolog of the cpn10 co-chaperonin, but its gene consists of two cpn10-like units joined head-to-tail by a short chain of amino acids. This double protein is unique to plastids and was shown to exist in plants as well plastid-containing parasites. In vitro assays showed that this cpn20 co-chaperonin is a functional homolog of cpn10. In terms of structure, existing data indicate that the oligomer is tetrameric, yet it interacts with a heptameric cpn60 partner. Thus, the functional oligomeric structure remains a mystery. In this review, we summarize what is known about this distinctive chaperonin and use a bioinformatics approach to examine the expression of cpn20 in Arabidopsis thaliana relative to other chaperonin genes in this species. In addition, we examine the primary structure of the two homologous domains for similarities and differences, in comparison with cpn10 from other species. Lastly, we hypothesize as to the oligomeric structure and raison d'être of this unusual co-chaperonin homolog. PMID:19031045

  1. CHAPERONIN 20 mediates iron superoxide dismutase (FeSOD) activity independent of its co-chaperonin role in Arabidopsis chloroplasts.

    PubMed

    Kuo, W Y; Huang, C H; Liu, A C; Cheng, C P; Li, S H; Chang, W C; Weiss, C; Azem, A; Jinn, T L

    2013-01-01

    Iron superoxide dismutases (FeSODs; FSDs) are primary antioxidant enzymes in Arabidopsis thaliana chloroplasts. The stromal FSD1 conferred the only detectable FeSOD activity, whereas the thylakoid membrane- and nucleoid-co-localized FSD2 and FSD3 double mutant showed arrested chloroplast development. FeSOD requires cofactor Fe for its activity, but its mechanism of activation is unclear. We used reversed-phase high-performance liquid chromatography (HPLC), gel filtration chromatography, LC-MS/MS, protoplast transient expression and virus-induced gene silencing (VIGS) analyses to identify and characterize a factor involved in FeSOD activation. We identified the chloroplast-localized co-chaperonin CHAPERONIN 20 (CPN20) as a mediator of FeSOD activation by direct interaction. The relationship between CPN20 and FeSOD was confirmed by in vitro experiments showing that CPN20 alone could enhance FSD1, FSD2 and FSD3 activity. The in vivo results showed that CPN20-overexpressing mutants and mutants with defective co-chaperonin activity increased FSD1 activity, without changing the chaperonin CPN60 protein level, and VIGS-induced downregulation of CPN20 also led to decreased FeSOD activity. Our findings reveal that CPN20 can mediate FeSOD activation in chloroplasts, a role independent of its known function in the chaperonin system. PMID:23057508

  2. Identification of elements that dictate the specificity of mitochondrial Hsp60 for its co-chaperonin.

    PubMed

    Parnas, Avital; Nisemblat, Shahar; Weiss, Celeste; Levy-Rimler, Galit; Pri-Or, Amir; Zor, Tsaffrir; Lund, Peter A; Bross, Peter; Azem, Abdussalam

    2012-01-01

    Type I chaperonins (cpn60/Hsp60) are essential proteins that mediate the folding of proteins in bacteria, chloroplast and mitochondria. Despite the high sequence homology among chaperonins, the mitochondrial chaperonin system has developed unique properties that distinguish it from the widely-studied bacterial system (GroEL and GroES). The most relevant difference to this study is that mitochondrial chaperonins are able to refold denatured proteins only with the assistance of the mitochondrial co-chaperonin. This is in contrast to the bacterial chaperonin, which is able to function with the help of co-chaperonin from any source. The goal of our work was to determine structural elements that govern the specificity between chaperonin and co-chaperonin pairs using mitochondrial Hsp60 as model system. We used a mutagenesis approach to obtain human mitochondrial Hsp60 mutants that are able to function with the bacterial co-chaperonin, GroES. We isolated two mutants, a single mutant (E321K) and a double mutant (R264K/E358K) that, together with GroES, were able to rescue an E. coli strain, in which the endogenous chaperonin system was silenced. Although the mutations are located in the apical domain of the chaperonin, where the interaction with co-chaperonin takes place, none of the residues are located in positions that are directly responsible for co-chaperonin binding. Moreover, while both mutants were able to function with GroES, they showed distinct functional and structural properties. Our results indicate that the phenotype of the E321K mutant is caused mainly by a profound increase in the binding affinity to all co-chaperonins, while the phenotype of R264K/E358K is caused by a slight increase in affinity toward co-chaperonins that is accompanied by an alteration in the allosteric signal transmitted upon nucleotide binding. The latter changes lead to a great increase in affinity for GroES, with only a minor increase in affinity toward the mammalian mitochondrial co-chaperonin

  3. Identification of Elements That Dictate the Specificity of Mitochondrial Hsp60 for Its Co-Chaperonin

    PubMed Central

    Weiss, Celeste; Levy-Rimler, Galit; Pri-Or, Amir; Zor, Tsaffrir; Lund, Peter A.; Bross, Peter; Azem, Abdussalam

    2012-01-01

    Type I chaperonins (cpn60/Hsp60) are essential proteins that mediate the folding of proteins in bacteria, chloroplast and mitochondria. Despite the high sequence homology among chaperonins, the mitochondrial chaperonin system has developed unique properties that distinguish it from the widely-studied bacterial system (GroEL and GroES). The most relevant difference to this study is that mitochondrial chaperonins are able to refold denatured proteins only with the assistance of the mitochondrial co-chaperonin. This is in contrast to the bacterial chaperonin, which is able to function with the help of co-chaperonin from any source. The goal of our work was to determine structural elements that govern the specificity between chaperonin and co-chaperonin pairs using mitochondrial Hsp60 as model system. We used a mutagenesis approach to obtain human mitochondrial Hsp60 mutants that are able to function with the bacterial co-chaperonin, GroES. We isolated two mutants, a single mutant (E321K) and a double mutant (R264K/E358K) that, together with GroES, were able to rescue an E. coli strain, in which the endogenous chaperonin system was silenced. Although the mutations are located in the apical domain of the chaperonin, where the interaction with co-chaperonin takes place, none of the residues are located in positions that are directly responsible for co-chaperonin binding. Moreover, while both mutants were able to function with GroES, they showed distinct functional and structural properties. Our results indicate that the phenotype of the E321K mutant is caused mainly by a profound increase in the binding affinity to all co-chaperonins, while the phenotype of R264K/E358K is caused by a slight increase in affinity toward co-chaperonins that is accompanied by an alteration in the allosteric signal transmitted upon nucleotide binding. The latter changes lead to a great increase in affinity for GroES, with only a minor increase in affinity toward the mammalian mitochondrial co-chaperonin

  4. Versatile platform for nanotechnology based on circular permutations of chaperonin protein

    NASA Technical Reports Server (NTRS)

    Paavola, Chad D. (Inventor); Trent, Jonathan D. (Inventor); Chan, Suzanne L. (Inventor); Li, Yi-Fen (Inventor); McMillan, R. Andrew (Inventor); Kagawa, Hiromi (Inventor)

    2010-01-01

    The present invention provides chaperonin polypeptides which are modified to include N-terminal and C-terminal ends that are relocated from the central pore region to various different positions in the polypeptide which are located on the exterior of the folded modified chaperonin polypeptide. In the modified chaperonin polypeptide, the naturally-occurring N-terminal and C-terminal ends are joined together directly or with an intervening linker peptide sequence. The relocated N-terminal or C-terminal ends can be covalently joined to, or bound with another molecule such as a nucleic acid molecule, a lipid, a carbohydrate, a second polypeptide, or a nanoparticle. The modified chaperonin polypeptides can assemble into double-ringed chaperonin structures. Further, the chaperonin structures can organize into higher order structures such as nanofilaments or nanoarrays which can be used to produce nanodevices and nanocoatings.

  5. Cellular chaperonin CCTγ contributes to rabies virus replication during infection.

    PubMed

    Zhang, Jinyang; Wu, Xiaopeng; Zan, Jie; Wu, Yongping; Ye, Chengjin; Ruan, Xizhen; Zhou, Jiyong

    2013-07-01

    Rabies, as the oldest known infectious disease, remains a serious threat to public health worldwide. The eukaryotic cytosolic chaperonin TRiC/CCT complex facilitates the folding of proteins through ATP hydrolysis. Here, we investigated the expression, cellular localization, and function of neuronal CCTγ during neurotropic rabies virus (RABV) infection using mouse N2a cells as a model. Following RABV infection, 24 altered proteins were identified by using two-dimensional electrophoresis and mass spectrometry, including 20 upregulated proteins and 4 downregulated proteins. In mouse N2a cells infected with RABV or cotransfected with RABV genes encoding nucleoprotein (N) and phosphoprotein (P), confocal microscopy demonstrated that upregulated cellular CCTγ was colocalized with viral proteins N and P, which formed a hollow cricoid inclusion within the region around the nucleus. These inclusions, which correspond to Negri bodies (NBs), did not form in mouse N2a cells only expressing the viral protein N or P. Knockdown of CCTγ by lentivirus-mediated RNA interference led to significant inhibition of RABV replication. These results demonstrate that the complex consisting of viral proteins N and P recruits CCTγ to NBs and identify the chaperonin CCTγ as a host factor that facilitates intracellular RABV replication. This work illustrates how viruses can utilize cellular chaperonins and compartmentalization for their own benefit. PMID:23637400

  6. Cellular Chaperonin CCTγ Contributes to Rabies Virus Replication during Infection

    PubMed Central

    Zhang, Jinyang; Wu, Xiaopeng; Zan, Jie; Wu, Yongping; Ye, Chengjin; Ruan, Xizhen

    2013-01-01

    Rabies, as the oldest known infectious disease, remains a serious threat to public health worldwide. The eukaryotic cytosolic chaperonin TRiC/CCT complex facilitates the folding of proteins through ATP hydrolysis. Here, we investigated the expression, cellular localization, and function of neuronal CCTγ during neurotropic rabies virus (RABV) infection using mouse N2a cells as a model. Following RABV infection, 24 altered proteins were identified by using two-dimensional electrophoresis and mass spectrometry, including 20 upregulated proteins and 4 downregulated proteins. In mouse N2a cells infected with RABV or cotransfected with RABV genes encoding nucleoprotein (N) and phosphoprotein (P), confocal microscopy demonstrated that upregulated cellular CCTγ was colocalized with viral proteins N and P, which formed a hollow cricoid inclusion within the region around the nucleus. These inclusions, which correspond to Negri bodies (NBs), did not form in mouse N2a cells only expressing the viral protein N or P. Knockdown of CCTγ by lentivirus-mediated RNA interference led to significant inhibition of RABV replication. These results demonstrate that the complex consisting of viral proteins N and P recruits CCTγ to NBs and identify the chaperonin CCTγ as a host factor that facilitates intracellular RABV replication. This work illustrates how viruses can utilize cellular chaperonins and compartmentalization for their own benefit. PMID:23637400

  7. Functionality and Evolutionary History of the Chaperonins in Thermophilic Archaea. A Bioinformatical Perspective

    NASA Technical Reports Server (NTRS)

    Karlin, Samuel

    2004-01-01

    We used bioinformatics methods to study phylogenetic relations and differentiation patterns of the archaeal chaperonin 60 kDa heat-shock protein (HSP60) genes in support of the study of differential expression patterns of the three chaperonin genes encoded in Sulfolobus shibatae.

  8. Crystallization and structure determination of a symmetrical 'football' complex of the mammalian mitochondrial Hsp60-Hsp10 chaperonins.

    PubMed

    Nisemblat, Shahar; Parnas, Avital; Yaniv, Oren; Azem, Abdussalam; Frolow, Felix

    2014-01-01

    The mitochondrial Hsp60-Hsp10 complex assists the folding of various proteins impelled by ATP hydrolysis, similar to the bacterial chaperonins GroEL and GroES. The near-atomic structural details of the mitochondrial chaperonins are not known, despite the fact that almost two decades have passed since the structures of the bacterial chaperonins became available. Here, the crystallization procedure, diffraction experiments and structure determination by molecular replacement of the mammalian mitochondrial chaperonin HSP60 (E321K mutant) and its co-chaperonin Hsp10 are reported. PMID:24419632

  9. Dataset concerning GroEL chaperonin interaction with proteins

    PubMed Central

    Marchenkov, V.V.; Marchenko, N.Yu.; Kaysheva, A.L.; Kotova, N.V.; Kashparov, I.A.; Semisotnov, G.V.

    2016-01-01

    GroEL chaperonin is well-known to interact with a wide variety of polypeptide chains. Here we show the data related to our previous work (http://dx.doi.org/10.1016/j.pep.2015.11.020[1]), and concerning the interaction of GroEL with native (lysozyme, α-lactalbumin) and denatured (lysozyme, α-lactalbumin and pepsin) proteins in solution. The use of affinity chromatography on the base of denatured pepsin for GroEL purification from fluorescent impurities is represented as well. PMID:26909376

  10. Characterization of group II chaperonins from an acidothermophilic archaeon Picrophilus torridus.

    PubMed

    Yamamoto, Yohei Y; Tsuchida, Kanako; Noguchi, Keiichi; Ogawa, Naoki; Sekiguchi, Hiroshi; Sasaki, Yuji C; Yohda, Masafumi

    2016-07-01

    Chaperonins are a type of molecular chaperone that assist in the folding of proteins. Group II chaperonins play an important role in the proteostasis in the cytosol of archaea and eukarya. In this study, we expressed, purified, and characterized group II chaperonins from an acidothermophilic archaeon Picrophilus torridus. Two genes exist for group II chaperonins, and both of the gene products assemble to form double-ring complexes similar to other archaeal group II chaperonins. One of the Picrophilus chaperonins, PtoCPNα, was able to refold denatured GFP at 50 °C. As expected, PtoCPNα exhibited an ATP-dependent conformational change that is observed by the change in fluorescence and diffracted X-ray tracking (DXT). In contrast, PtoCPNα lost its protein folding ability at moderate temperatures, becoming unable to interact with unfolded proteins. At lower temperatures, the release rate of the captured GFP from PtoCPNα was accelerated, and the affinity of denatured protein to PtoCPNα was weakened at the lower temperatures. Unexpectedly, in the DXT experiment, the fine motions were enhanced at the lower temperatures. Taken together, the results suggest that the fine tilting motions of the apical domain might correlate with the affinity of group II chaperonins for denatured proteins. PMID:27398315

  11. Engineering a nanopore with co-chaperonin function

    PubMed Central

    Ho, Ching-Wen; Van Meervelt, Veerle; Tsai, Keng-Chang; De Temmerman, Pieter-Jan; Mast, Jan; Maglia, Giovanni

    2015-01-01

    The emergence of an enzymatic function can reveal functional insights and allows the engineering of biological systems with enhanced properties. We engineered an alpha hemolysin nanopore to function as GroES, a protein that, in complex with GroEL, forms a two-stroke protein-folding nanomachine. The transmembrane co-chaperonin was prepared by recombination of GroES functional elements with the nanopore, suggesting that emergent functions in molecular machines can be added bottom-up by incorporating modular elements into preexisting protein scaffolds. The binding of a single-ring version of GroEL to individual GroES nanopores prompted large changes to the unitary nanopore current, most likely reflecting the allosteric transitions of the chaperonin apical domains. One of the GroEL-induced current levels showed fast fluctuations (<1 ms), a characteristic that might be instrumental for efficient substrate encapsulation or folding. In the presence of unfolded proteins, the pattern of current transitions changed, suggesting a possible mechanism in which the free energy of adenosine triphosphate binding and hydrolysis is expended only when substrate proteins are occupied. PMID:26824063

  12. Eukaryotic cytosolic chaperonin contains t-complex polypeptide 1 and seven related subunits.

    PubMed Central

    Rommelaere, H; Van Troys, M; Gao, Y; Melki, R; Cowan, N J; Vandekerckhove, J; Ampe, C

    1993-01-01

    We have characterized the cytosolic chaperonin from both rabbit reticulocyte lysate and bovine testis. The heteromeric complex contains eight subunits. Partial amino acid sequence data reveal that one of these is t-complex polypeptide 1 (TCP-1), while the other seven are TCP-1-related polypeptides, implicating the existence of a multigene family of TCP-1 homologues. We provide evidence that TCP-1 ring complex from bovine testis can facilitate the folding of both actin and tubulin, although, as in the case of chaperonin from reticulocyte lysate, two cofactors are required for the generation of properly folded tubulin. An additional molecule of TCP-1 may associate with the chaperonin depending on the purification procedure used. We propose that a highly conserved region in these polypeptides and in other chaperonins of the cpn60 chaperone family participates in ATP binding. Images Fig. 1 Fig. 2 Fig. 3 PMID:7903455

  13. Expression and Functional Characterization of the First Bacteriophage-Encoded Chaperonin

    PubMed Central

    Semenyuk, Pavel I.; Orlov, Victor N.; Robben, Johan; Sykilinda, Nina N.; Mesyanzhinov, Vadim V.

    2012-01-01

    Chaperonins promote protein folding in vivo and are ubiquitously found in bacteria, archaea, and eukaryotes. The first viral chaperonin GroEL ortholog, gene product 146 (gp146), whose gene was earlier identified in the genome of bacteriophage EL, has been shown to be synthesized during phage propagation in Pseudomonas aeruginosa cells. The recombinant gp146 has been expressed in Escherichia coli and characterized by different physicochemical methods for the first time. Using serum against the recombinant protein, gp146's native substrate, the phage endolysin gp188, has been immunoprecipitated from the lysate of EL-infected bacteria and identified by mass spectrometry. In vitro experiments have shown that gp146 has a protective effect against endolysin thermal inactivation and aggregation, providing evidence of its chaperonin function. The phage chaperonin has been found to have the architecture and some properties similar to those of GroEL but not to require cochaperonin for its functional activity. PMID:22787217

  14. Computational modeling of protein folding assistance by the eukaryotic chaperonin CCT

    NASA Astrophysics Data System (ADS)

    Jayasinghe, Manori; Stan, George

    2009-03-01

    Chaperonins are biological nanomachines that promote protein folding using energy derived from ATP hydrolysis. Structurally, chaperonins are large oligomeric complexes that form double-ring construct, enclosing a central cavity that serves as folding chamber. Our focus is on the substrate binding mechanisms of the Eukaryotic chaperonin CCT and Archaeal chaperonin Thermosome. We contrast our results with the annealing action of the bacterial chaperonin GroEL of E. coli., currently the best studied for chaperonin machinery. CCT was suggested to be more selective towards the substrate recognition where as GroEL is more promiscuous due to the hydrophobic interactions. We study the interaction of CCT with Tubulin, one of its stringent substrates. Using molecular docking and molecular dynamics simulations, we probe binding of a βtubulin peptide (205-274) to the CCTγ apical domain. We identify a versatile binding mechanism, involving mostly hydrophobic interactions with the helical region and electrostatic interactions with the helical protrusion region. This specific substrate-protein recognition mechanism is likely to be optimized for specific substrate protein-CCT subunit pairs.

  15. Chloroplast β chaperonins from A. thaliana function with endogenous cpn10 homologs in vitro.

    PubMed

    Vitlin, Anna; Weiss, Celeste; Demishtein-Zohary, Keren; Rasouly, Aviram; Levin, Doron; Pisanty-Farchi, Odelia; Breiman, Adina; Azem, Abdussalam

    2011-09-01

    The involvement of type I chaperonins in bacterial and organellar protein folding has been well-documented. In E. coli and mitochondria, these ubiquitous and highly conserved proteins form chaperonin oligomers of identical 60 kDa subunits (cpn60), while in chloroplasts, two distinct cpn60 α and β subunit types co-exist together. The primary sequence of α and β subunits is ~50% identical, similar to their respective homologies to the bacterial GroEL. Moreover, the A. thaliana genome contains two α and four β genes. The functional significance of this variability in plant chaperonin proteins has not yet been elucidated. In order to gain insight into the functional variety of the chloroplast chaperonin family members, we reconstituted β homo-oligomers from A. thaliana following their expression in bacteria and subjected them to a structure-function analysis. Our results show for the first time, that A. thaliana β homo-oligomers can function in vitro with authentic chloroplast co-chaperonins (ch-cpn10 and ch-cpn20). We also show that oligomers made up of different β subunit types have unique properties and different preferences for co-chaperonin partners. We propose that chloroplasts may contain active β homo-oligomers in addition to hetero-oligomers, possibly reflecting a variety of cellular roles. PMID:21633907

  16. Trivalent Arsenic Inhibits the Functions of Chaperonin Complex

    PubMed Central

    Pan, Xuewen; Reissman, Stefanie; Douglas, Nick R.; Huang, Zhiwei; Yuan, Daniel S.; Wang, Xiaoling; McCaffery, J. Michael; Frydman, Judith; Boeke, Jef D.

    2010-01-01

    The exact molecular mechanisms by which the environmental pollutant arsenic works in biological systems are not completely understood. Using an unbiased chemogenomics approach in Saccharomyces cerevisiae, we found that mutants of the chaperonin complex TRiC and the functionally related prefoldin complex are all hypersensitive to arsenic compared to a wild-type strain. In contrast, mutants with impaired ribosome functions were highly arsenic resistant. These observations led us to hypothesize that arsenic might inhibit TRiC function, required for folding of actin, tubulin, and other proteins postsynthesis. Consistent with this hypothesis, we found that arsenic treatment distorted morphology of both actin and microtubule filaments. Moreover, arsenic impaired substrate folding by both bovine and archaeal TRiC complexes in vitro. These results together indicate that TRiC is a conserved target of arsenic inhibition in various biological systems. PMID:20660648

  17. Trivalent arsenic inhibits the functions of chaperonin complex.

    PubMed

    Pan, Xuewen; Reissman, Stefanie; Douglas, Nick R; Huang, Zhiwei; Yuan, Daniel S; Wang, Xiaoling; McCaffery, J Michael; Frydman, Judith; Boeke, Jef D

    2010-10-01

    The exact molecular mechanisms by which the environmental pollutant arsenic works in biological systems are not completely understood. Using an unbiased chemogenomics approach in Saccharomyces cerevisiae, we found that mutants of the chaperonin complex TRiC and the functionally related prefoldin complex are all hypersensitive to arsenic compared to a wild-type strain. In contrast, mutants with impaired ribosome functions were highly arsenic resistant. These observations led us to hypothesize that arsenic might inhibit TRiC function, required for folding of actin, tubulin, and other proteins postsynthesis. Consistent with this hypothesis, we found that arsenic treatment distorted morphology of both actin and microtubule filaments. Moreover, arsenic impaired substrate folding by both bovine and archaeal TRiC complexes in vitro. These results together indicate that TRiC is a conserved target of arsenic inhibition in various biological systems. PMID:20660648

  18. A compromise on abortion?

    PubMed

    Rhoden, N K

    1989-01-01

    Rhoden's article is one of three on "Abortion: searching for common ground" in this issue of the Hastings Center Report. Her article, together with those by M. Mahowald and M. Glendon, was prompted by the expectation that the impending U.S. Supreme Court decision in Webster v. Reproductive Health Services (3 July 1989) would overturn or restrict Roe v. Wade (1973). Rhoden, an advocate for the pro-choice position, asks whether a compromise leading to an acceptable regulatory policy is possible or desirable among those on opposite sides of the abortion issue. She identifies several reasons why the Roe decision is vulnerable to review, but argues that effective education about sexuality and comprehensive social support of women are better approaches to abortion than restrictive legislation. PMID:2663778

  19. The Legionella pneumophila Chaperonin - An Unusual Multifunctional Protein in Unusual Locations.

    PubMed

    Garduño, Rafael A; Chong, Audrey; Nasrallah, Gheyath K; Allan, David S

    2011-01-01

    The Legionella pneumophila chaperonin, high temperature protein B (HtpB), was discovered as a highly immunogenic antigen, only a few years after the identification of L. pneumophila as the causative agent of Legionnaires' disease. As its counterparts in other bacterial pathogens, HtpB did not initially receive further attention, particularly because research was focused on a few model chaperonins that were used to demonstrate that chaperonins are essential stress proteins, present in all cellular forms of life and involved in helping other proteins to fold. However, chaperonins have recently attracted increasing interest, particularly after several reports confirmed their multifunctional nature and the presence of multiple chaperonin genes in numerous bacterial species. It is now accepted that bacterial chaperonins are capable of playing a variety of protein folding-independent roles. HtpB is clearly a multifunctional chaperonin that according to its location in the bacterial cell, or in the L. pneumophila-infected cell, plays different roles. HtpB exposed on the bacterial cell surface can act as an invasion factor for non-phagocytic cells, whereas the HtpB released in the host cell can act as an effector capable of altering organelle trafficking, the organization of actin microfilaments and cell signaling pathways. The road to discover the multifunctional nature of HtpB has been exciting and here we provide a historical perspective of the key findings linked to such discovery, as well as a summary of the experimental work (old and new) performed in our laboratory. Our current understanding has led us to propose that HtpB is an ancient protein that L. pneumophila uses as a key molecular tool important to the intracellular establishment of this fascinating pathogen. PMID:21713066

  20. The medically compromised patient.

    PubMed

    Parnell, A G

    1986-06-01

    Diabetes mellitus is found in up to 5 per cent of the population. There is an excess of blood sugar due to a deficiency or diminished effectiveness of insulin. It is a complex disease which, if not controlled, has many major complications including an increased incidence of heart attacks, strokes and vascular changes in many other organs. The management of young onset diabetic patients is directed towards: controlling the carbohydrate intake, testing the blood sugar by the patient and regular insulin injections. Great care must be taken in treating diabetics in the dental surgery. Except for children, any diabetic can be treated for simple dental procedures by ensuring freedom from pain, by eliminating stress and by ensuring that the patient does not miss a meal. Children, unstable diabetic patients and those with infections or requiring multiple extractions should be treated in hospital under the care of an endocrinologist. In hypertension it is only after a number of years that complications begin to appear. The main ones are those of stroke, retinal haemorrhages, renal failure and heart disease. Dentists should be encouraged to take the blood pressure of all adults who present for treatment. Patients with increased blood pressure yet controlled by drugs may be treated as normal patients. Those that are not well controlled should be referred to their physician. Dental appointments must be free of pain and stress should be avoided. A screening method is presented which assists in the evaluation of medically compromised patients. PMID:2941377

  1. Arabidopsis chloroplast chaperonin 10 is a calmodulin-binding protein

    NASA Technical Reports Server (NTRS)

    Yang, T.; Poovaiah, B. W.

    2000-01-01

    Calcium regulates diverse cellular activities in plants through the action of calmodulin (CaM). By using (35)S-labeled CaM to screen an Arabidopsis seedling cDNA expression library, a cDNA designated as AtCh-CPN10 (Arabidopsis thaliana chloroplast chaperonin 10) was cloned. Chloroplast CPN10, a nuclear-encoded protein, is a functional homolog of E. coli GroES. It is believed that CPN60 and CPN10 are involved in the assembly of Rubisco, a key enzyme involved in the photosynthetic pathway. Northern analysis revealed that AtCh-CPN10 is highly expressed in green tissues. The recombinant AtCh-CPN10 binds to CaM in a calcium-dependent manner. Deletion mutants revealed that there is only one CaM-binding site in the last 31 amino acids of the AtCh-CPN10 at the C-terminal end. The CaM-binding region in AtCh-CPN10 has higher homology to other chloroplast CPN10s in comparison to GroES and mitochondrial CPN10s, suggesting that CaM may only bind to chloroplast CPN10s. Furthermore, the results also suggest that the calcium/CaM messenger system is involved in regulating Rubisco assembly in the chloroplast, thereby influencing photosynthesis. Copyright 2000 Academic Press.

  2. [Tuberculosis in compromised hosts].

    PubMed

    2003-11-01

    Recent development of tuberculosis in Japan tends to converge on a specific high risk group. The proportion of tuberculosis developing particularly from the compromised hosts in the high risk group is especially high. At this symposium, therefore, we took up diabetes mellitus, gastrectomy, dialysis, AIDS and the elderly for discussion. Many new findings and useful reports for practical medical treatment are submitted; why these compromised hosts are predisposed to tuberculosis, tuberculosis diagnostic and remedial notes of those compromised hosts etc. It is an important question for the future to study how to prevent tuberculosis from these compromised hosts. 1. Tuberculosis in diabetes mellitus: aggravation and its immunological mechanism: Kazuyoshi KAWAKAMI (Department of Internal Medicine, Division of Infectious Diseases, Graduate School and Faculty of Medicine, University of the Ryukyus). It has been well documented that diabetes mellitus (DM) is a major aggravating factor in tuberculosis. The onset of this disease is more frequent in DM patients than in individuals with any underlying diseases. However, the precise mechanism of this finding remains to be fully understood. Earlier studies reported that the migration, phagocytosis and bactericidal activity of neutrophils are all impaired in DM patients, which is related to their reduced host defense to infection with extracellular bacteria, such as S. aureus and E. colli. Host defense to mycobacterial infection is largely mediated by cellular immunity, and Th1-related cytokines, such as IFN-gamma and IL-12, play a central role in this response. It is reported that serum level of these cytokines and their production by peripheral blood mononuclear cells (PBMC) are reduced in tuberculosis patients with DM, and this is supposed to be involved in the high incidence of tuberculosis in DM. Our study observed similar findings and furthermore indicated that IFN-gamma and IL-12 production by BCG-stimulated PBMC was lower

  3. The GroEL-GroES Chaperonin Machine: A Nano-Cage for Protein Folding.

    PubMed

    Hayer-Hartl, Manajit; Bracher, Andreas; Hartl, F Ulrich

    2016-01-01

    The bacterial chaperonin GroEL and its cofactor GroES constitute the paradigmatic molecular machine of protein folding. GroEL is a large double-ring cylinder with ATPase activity that binds non-native substrate protein (SP) via hydrophobic residues exposed towards the ring center. Binding of the lid-shaped GroES to GroEL displaces the bound protein into an enlarged chamber, allowing folding to occur unimpaired by aggregation. GroES and SP undergo cycles of binding and release, regulated allosterically by the GroEL ATPase. Recent structural and functional studies are providing insights into how the physical environment of the chaperonin cage actively promotes protein folding, in addition to preventing aggregation. Here, we review different models of chaperonin action and discuss issues of current debate. PMID:26422689

  4. Single-molecule spectroscopy of protein folding in a chaperonin cage

    PubMed Central

    Hofmann, Hagen; Hillger, Frank; Pfeil, Shawn H.; Hoffmann, Armin; Streich, Daniel; Haenni, Dominik; Nettels, Daniel; Lipman, Everett A.; Schuler, Benjamin

    2010-01-01

    Molecular chaperones are known to be essential for avoiding protein aggregation in vivo, but it is still unclear how they affect protein folding mechanisms. We use single-molecule Förster resonance energy transfer to follow the folding of a protein inside the GroEL/GroES chaperonin cavity over a time range from milliseconds to hours. Our results show that confinement in the chaperonin decelerates the folding of the C-terminal domain in the substrate protein rhodanese, but leaves the folding rate of the N-terminal domain unaffected. Microfluidic mixing experiments indicate that strong interactions of the substrate with the cavity walls impede the folding process, but the folding hierarchy is preserved. Our results imply that no universal chaperonin mechanism exists. Rather, a competition between intra- and intermolecular interactions determines the folding rates and mechanisms of a substrate inside the GroEL/GroES cage. PMID:20547872

  5. Crystallization and structure determination of a symmetrical ‘football’ complex of the mammalian mitochondrial Hsp60–Hsp10 chaperonins

    PubMed Central

    Nisemblat, Shahar; Parnas, Avital; Yaniv, Oren; Azem, Abdussalam; Frolow, Felix

    2014-01-01

    The mitochondrial Hsp60–Hsp10 complex assists the folding of various proteins impelled by ATP hydrolysis, similar to the bacterial chaperonins GroEL and GroES. The near-atomic structural details of the mitochondrial chaperonins are not known, despite the fact that almost two decades have passed since the structures of the bacterial chaperonins became available. Here, the crystallization procedure, diffraction experiments and structure determination by molecular replacement of the mammalian mitochondrial chaperonin HSP60 (E321K mutant) and its co-chaperonin Hsp10 are reported. PMID:24419632

  6. Differential effects of co-chaperonin homologs on cpn60 oligomers

    PubMed Central

    Bonshtien, Anat L.; Parnas, Avital; Sharkia, Rajach; Niv, Adina; Mizrahi, Itzhak; Weiss, Celeste

    2009-01-01

    In this study, we have investigated the relationship between chaperonin/co-chaperonin binding, ATP hydrolysis, and protein refolding in heterologous chaperonin systems from bacteria, chloroplast, and mitochondria. We characterized two types of chloroplast cpn60 oligomers, ch-cpn60 composed of α and β subunits (α7β7 ch-cpn60) and one composed of all β subunits (β14 ch-cpn60). In terms of ATPase activity, the rate of ATP hydrolysis increased with protein concentration up to 60 μM, reflecting a concentration at which the oligomers are stable. At high concentrations of cpn60, all cpn10 homologs inhibited ATPase activity of α7β7 ch-cpn60. In contrast, ATPase of β14 ch-cpn60 was inhibited only by mitochondrial cpn10, supporting previous reports showing that β14 is functional only with mitochondrial cpn10 and not with other cpn10 homologs. Surprisingly, direct binding assays showed that both ch-cpn60 oligomer types bind to bacterial, mitochondrial, and chloroplast cpn10 homologs with an equal apparent affinity. Moreover, mitochondrial cpn60 binds chloroplast cpn20 with which it is not able to refold denatured proteins. Protein refolding experiments showed that in such instances, the bound protein is released in a conformation that is not able to refold. The presence of glycerol, or subsequent addition of mitochondrial cpn10, allows us to recover enzymatic activity of the substrate protein. Thus, in our systems, the formation of co-chaperonin/chaperonin complexes does not necessarily lead to protein folding. By using heterologous oligomer systems, we are able to separate the functions of binding and refolding in order to better understand the chaperonin mechanism. PMID:19224397

  7. Differential effects of co-chaperonin homologs on cpn60 oligomers.

    PubMed

    Bonshtien, Anat L; Parnas, Avital; Sharkia, Rajach; Niv, Adina; Mizrahi, Itzhak; Azem, Abdussalam; Weiss, Celeste

    2009-09-01

    In this study, we have investigated the relationship between chaperonin/co-chaperonin binding, ATP hydrolysis, and protein refolding in heterologous chaperonin systems from bacteria, chloroplast, and mitochondria. We characterized two types of chloroplast cpn60 oligomers, ch-cpn60 composed of alpha and beta subunits (alpha(7)beta(7) ch-cpn60) and one composed of all beta subunits (beta(14) ch-cpn60). In terms of ATPase activity, the rate of ATP hydrolysis increased with protein concentration up to 60 microM, reflecting a concentration at which the oligomers are stable. At high concentrations of cpn60, all cpn10 homologs inhibited ATPase activity of alpha(7)beta(7) ch-cpn60. In contrast, ATPase of beta(14) ch-cpn60 was inhibited only by mitochondrial cpn10, supporting previous reports showing that beta(14) is functional only with mitochondrial cpn10 and not with other cpn10 homologs. Surprisingly, direct binding assays showed that both ch-cpn60 oligomer types bind to bacterial, mitochondrial, and chloroplast cpn10 homologs with an equal apparent affinity. Moreover, mitochondrial cpn60 binds chloroplast cpn20 with which it is not able to refold denatured proteins. Protein refolding experiments showed that in such instances, the bound protein is released in a conformation that is not able to refold. The presence of glycerol, or subsequent addition of mitochondrial cpn10, allows us to recover enzymatic activity of the substrate protein. Thus, in our systems, the formation of co-chaperonin/chaperonin complexes does not necessarily lead to protein folding. By using heterologous oligomer systems, we are able to separate the functions of binding and refolding in order to better understand the chaperonin mechanism. PMID:19224397

  8. GroEL-Assisted Protein Folding: Does It Occur Within the Chaperonin Inner Cavity?

    PubMed Central

    Marchenkov, Victor V.; Semisotnov, Gennady V.

    2009-01-01

    The folding of protein molecules in the GroEL inner cavity under the co-chaperonin GroES lid is widely accepted as a crucial event of GroEL-assisted protein folding. This review is focused on the data showing that GroEL-assisted protein folding may proceed out of the complex with the chaperonin. The models of GroEL-assisted protein folding assuming ligand-controlled dissociation of nonnative proteins from the GroEL surface and their folding in the bulk solution are also discussed. PMID:19564940

  9. Isolation and characterization of a Paracentrotus lividus cDNA encoding a stress-inducible chaperonin

    PubMed Central

    Gianguzza, Fabrizio; Antonietta Ragusa, Maria; Roccheri, Maria Carmela; Liegro, Italia Di; Rinaldi, Anna Maria

    2000-01-01

    Chaperonins are ubiquitous proteins that facilitate protein folding in an adenosine triphosphate–dependent manner. Here we report the isolation of a sea urchin cDNA (Plhsp60) coding for mitochondrial chaperonin (Cpn60), whose basal expression is further enhanced by heat shock. The described cDNA corresponds to a full-length mRNA encoding a protein of 582 amino acids, the first 32 of which constitute a putative mitochondrial targeting leader sequence. Comparative analysis has demonstrated that this protein is highly conserved in evolution. PMID:11147969

  10. Protomer Roles in Chloroplast Chaperonin Assembly and Function.

    PubMed

    Bai, Cuicui; Guo, Peng; Zhao, Qian; Lv, Zongyang; Zhang, Shijia; Gao, Fei; Gao, Liyan; Wang, Yingchun; Tian, Zhixi; Wang, Jifeng; Yang, Fuquan; Liu, Cuimin

    2015-10-01

    The individual roles of three chloroplast CPN60 protomers (CPN60α, CPN60β1, and CPN60β2) and whether and how they are assembled into functional chaperonin complexes are investigated in Chlamydomonas reinhardtii. Protein complexes containing all three potential subunits were identified in Chlamydomonas, and their co-expression in Escherichia coli yielded a homogeneous population of oligomers containing all three subunits (CPN60αβ1β2), with a molecular weight consistent with a tetradecameric structure. While homo-oligomers of CPN60β could form, they were dramatically reduced when CPN60α was present and homo-oligomers of CPN60β2 were readily changed into hetero-oligomers in the presence of ATP and other protomers. ATP hydrolysis caused CPN60 oligomers to disassemble and drove the purified protomers to reconstitute oligomers in vitro, suggesting that the dynamic nature of CPN60 oligomers is dependent on ATP. Only hetero-oligomeric CPN60αβ1β2, containing CPN60α, CPN60β1, and CPN60β2 subunits in a 5:6:3 ratio, cooperated functionally with GroES. The combination of CPN60α and CPN60β subunits, but not the individual subunits alone, complemented GroEL function in E. coli with subunit recognition specificity. Down-regulation of the CPN60α subunit in Chlamydomonas resulted in a slow growth defect and an inability to grow autotrophically, indicating the essential role of CPN60α in vivo. PMID:26057234

  11. P. falciparum cpn20 is a bona fide co-chaperonin that can replace GroES in E. coli.

    PubMed

    Vitlin Gruber, Anna; Nisemblat, Shahar; Zizelski, Gal; Parnas, Avital; Dzikowski, Ron; Azem, Abdussalam; Weiss, Celeste

    2013-01-01

    Human malaria is among the most ubiquitous and destructive tropical, parasitic diseases in the world today. The causative agent, Plasmodium falciparum, contains an unusual, essential organelle known as the apicoplast. Inhibition of this degenerate chloroplast results in second generation death of the parasite and is the mechanism by which antibiotics function in treating malaria. In order to better understand the biochemistry of this organelle, we have cloned a putative, 20 kDa, co-chaperonin protein, Pf-cpn20, which localizes to the apicoplast. Although this protein is homologous to the cpn20 that is found in plant chloroplasts, its ability to function as a co-chaperonin was questioned in the past. In the present study, we carried out a structural analysis of Pf-cpn20 using circular dichroism and analytical ultracentrifugation and then used two different approaches to investigate the ability of this protein to function as a co-chaperonin. In the first approach, we purified recombinant Pf-cpn20 and tested its ability to act as a co-chaperonin for GroEL in vitro, while in the second, we examined the ability of Pf-cpn20 to complement an E. coli depletion of the essential bacterial co-chaperonin GroES. Our results demonstrate that Pf-cpn20 is fully functional as a co-chaperonin in vitro. Moreover, the parasitic co-chaperonin is able to replace GroES in E. coli at both normal and heat-shock temperatures. Thus, Pf-cpn20 functions as a co-chaperonin in chaperonin-mediated protein folding. The ability of the malarial protein to function in E. coli suggests that this simple system can be used as a tool for further analyses of Pf-cpn20 and perhaps other chaperone proteins from P. falciparum. PMID:23326533

  12. P. falciparum cpn20 Is a Bona Fide Co-Chaperonin That Can Replace GroES in E. coli

    PubMed Central

    Vitlin Gruber, Anna; Nisemblat, Shahar; Zizelski, Gal; Parnas, Avital; Dzikowski, Ron; Azem, Abdussalam; Weiss, Celeste

    2013-01-01

    Human malaria is among the most ubiquitous and destructive tropical, parasitic diseases in the world today. The causative agent, Plasmodium falciparum, contains an unusual, essential organelle known as the apicoplast. Inhibition of this degenerate chloroplast results in second generation death of the parasite and is the mechanism by which antibiotics function in treating malaria. In order to better understand the biochemistry of this organelle, we have cloned a putative, 20 kDa, co-chaperonin protein, Pf-cpn20, which localizes to the apicoplast. Although this protein is homologous to the cpn20 that is found in plant chloroplasts, its ability to function as a co-chaperonin was questioned in the past. In the present study, we carried out a structural analysis of Pf-cpn20 using circular dichroism and analytical ultracentrifugation and then used two different approaches to investigate the ability of this protein to function as a co-chaperonin. In the first approach, we purified recombinant Pf-cpn20 and tested its ability to act as a co-chaperonin for GroEL in vitro, while in the second, we examined the ability of Pf-cpn20 to complement an E. coli depletion of the essential bacterial co-chaperonin GroES. Our results demonstrate that Pf-cpn20 is fully functional as a co-chaperonin in vitro. Moreover, the parasitic co-chaperonin is able to replace GroES in E. coli at both normal and heat-shock temperatures. Thus, Pf-cpn20 functions as a co-chaperonin in chaperonin-mediated protein folding. The ability of the malarial protein to function in E. coli suggests that this simple system can be used as a tool for further analyses of Pf-cpn20 and perhaps other chaperone proteins from P. falciparum. PMID:23326533

  13. Ring Separation Highlights the Protein-Folding Mechanism Used by the Phage EL-Encoded Chaperonin.

    PubMed

    Molugu, Sudheer K; Hildenbrand, Zacariah L; Morgan, David Gene; Sherman, Michael B; He, Lilin; Georgopoulos, Costa; Sernova, Natalia V; Kurochkina, Lidia P; Mesyanzhinov, Vadim V; Miroshnikov, Konstantin A; Bernal, Ricardo A

    2016-04-01

    Chaperonins are ubiquitous, ATP-dependent protein-folding molecular machines that are essential for all forms of life. Bacteriophage φEL encodes its own chaperonin to presumably fold exceedingly large viral proteins via profoundly different nucleotide-binding conformations. Our structural investigations indicate that ATP likely binds to both rings simultaneously and that a misfolded substrate acts as the trigger for ATP hydrolysis. More importantly, the φEL complex dissociates into two single rings resulting from an evolutionarily altered residue in the highly conserved ATP-binding pocket. Conformational changes also more than double the volume of the single-ring internal chamber such that larger viral proteins are accommodated. This is illustrated by the fact that φEL is capable of folding β-galactosidase, a 116-kDa protein. Collectively, the architecture and protein-folding mechanism of the φEL chaperonin are significantly different from those observed in group I and II chaperonins. PMID:26996960

  14. Three conformations of an Archaeal chaperonin, TF55 from Sulfolobus shibatae.

    SciTech Connect

    Schoehn, G.; Quaite-Randall, E.; Joachimiak, A.; Saibil, H. R.; Biosciences Division; Birkbeck Coll.

    2000-02-25

    Chaperonins are cylindrical, oligomeric complexes, essential for viability and required for the folding of other proteins. The GroE (group I) subfamily, found in eubacteria, mitochondria and chloroplasts, have 7-fold symmetry and provide an enclosed chamber for protein subunit folding. The central cavity is transiently closed by interaction with the co-protein, GroES. The most prominent feature specific to the group II subfamily, found in archaea and in the eukaryotic cytosol, is a long insertion in the substrate-binding region. In the archaeal complex, this forms an extended structure acting as a built-in lid, obviating the need for a GroES-like co-factor. This extension occludes a site known to bind non-native polypeptides in GroEL. The site and nature of substrate interaction are not known for the group II subfamily. The atomic structure of the thermosome, an archaeal group II chaperonin, has been determined in a fully closed form, but the entry and exit of protein substrates requires transient opening. Although an open form has been investigated by electron microscopy, conformational changes in group II chaperonins are not well characterized. Using electron cryo-microscopy and three-dimensional reconstruction, we describe three conformations of a group II chaperonin, including an asymmetric, bullet-shaped form, revealing the range of domain movements in this subfamily.

  15. Streptococcus suis Serotypes Characterized by Analysis of Chaperonin 60 Gene Sequences

    PubMed Central

    Brousseau, Ronald; Hill, Janet E.; Préfontaine, Gabrielle; Goh, Swee-Han; Harel, Josée; Hemmingsen, Sean M.

    2001-01-01

    Streptococcus suis is an important pathogen of swine which occasionally infects humans as well. There are 35 serotypes known for this organism, and it would be desirable to develop rapid methods methods to identify and differentiate the strains of this species. To that effect, partial chaperonin 60 gene sequences were determined for the 35 serotype reference strains of S. suis. Analysis of a pairwise distance matrix showed that the distances ranged from 0 to 0.275 when values were calculated by the maximum-likelihood method. For five of the strains the distances from serotype 1 were greater than 0.1, and for two of these strains the distances were were more than 0.25, suggesting that they belong to a different species. Most of the nucleotide differences were silent; alignment of protein sequences showed that there were only 11 distinct sequences for the 35 strains under study. The chaperonin 60 gene phylogenetic tree was similar to the previously published tree based on 16S rRNA sequences, and it was also observed that strains with identical chaperonin 60 gene sequences tended to have identical 16S rRNA sequences. The chaperonin 60 gene sequences provided a higher level of discrimination between serotypes than the 16S RNA sequences provided and could form the basis for a diagnostic protocol. PMID:11571190

  16. Separation of E. coli chaperonin groEL from β-galactosidase without denaturation.

    PubMed

    Molugu, Sudheer K; Li, Jihui; Bernal, Ricardo A

    2015-12-15

    Chaperonins are a class of ubiquitous proteins that assist and accelerate protein folding in the cell. The Escherichia coli groEL is the best known and forms a complex with its co-chaperonin groES in the presence of ATP and assists in the folding of nascent and misfolded substrate proteins. The purification of recombinant groEL results in a nearly homogeneous sample that consistently co-purifies with the major contaminant E. coli β-galactosidase. Removal of β-galactosidase using column chromatography alone is exceedingly difficult. This is due to the fact that the overall size, surface charge, isoelectric point and hydrophobicity of groEL and β-galactosidase are very similar. Therefore purification of groEL chaperonin to homogeneity requires denaturation of the complex into monomers with urea for separating the groEL from contaminating β-galactosidase followed by reassembly of the chaperonin complex. Here, we present a simple procedure for separating β-galactosidase along with many other impurities from groEL preparations under non-denaturing conditions. The groEL is first salted out with 50% ammonium sulfate. This step also precipitates β-galactosidase but this is then salted out by the addition of magnesium chloride which leaves groEL in solution. All remaining contaminants are removed by column chromatography. PMID:26590880

  17. Chaperonin-enhanced Escherichia coli cell-free expression of functional CXCR4.

    PubMed

    Chi, Haixia; Wang, Xiaoqiang; Li, Jiqiang; Ren, Hao; Huang, Fang

    2016-08-10

    G protein-coupled receptors (GPCRs) are important therapeutic targets for a broad spectrum of diseases and disorders. Obtaining milligram quantities of functional receptors through the development of robust production methods are highly demanded to probe GPCR structure and functions. In this study, we analyzed synergies of the bacterial chaperonin GroEL-GroES and cell-free expression for the production of functionally folded C-X-C chemokine GPCR type 4 (CXCR4). The yield of soluble CXCR4 in the presence of detergent Brij-35 reached ∼1.1mg/ml. The chaperonin complex added was found to significantly enhance the productive folding of newly synthesized CXCR4, by increasing both the rate (∼30-fold) and the yield (∼1.3-fold) of folding over its spontaneous behavior. Meanwhile, the structural stability of CXCR4 was also improved with supplied GroEL-GroES, as was the soluble expression of biologically active CXCR4 with a ∼1.4-fold increase. The improved stability together with the higher ligand binding affinity suggests more efficient folding. The essential chaperonin GroEL was shown to be partially effective on its own, but for maximum efficiency both GroEL and its co-chaperonin GroES were necessary. The method reported here should prove generally useful for cell-free production of large amounts of natively folded GPCRs, and even other classes of membrane proteins. PMID:27316829

  18. Reversible denaturation of oligomeric human chaperonin 10: denatured state depends on chemical denaturant.

    PubMed Central

    Guidry, J. J.; Moczygemba, C. K.; Steede, N. K.; Landry, S. J.; Wittung-Stafshede, P.

    2000-01-01

    Chaperonins cpn60/cpn10 (GroEL/GroES in Escherichia coli) assist folding of nonnative polypeptides. Folding of the chaperonins themselves is distinct in that it entails assembly of a sevenfold symmetrical structure. We have characterized denaturation and renaturation of the recombinant human chaperonin 10 (cpn10), which forms a heptamer. Denaturation induced by chemical denaturants urea and guanidine hydrochloride (GuHCl) as well as by heat was monitored by tyrosine fluorescence, far-ultraviolet circular dichroism, and cross-linking; all denaturation reactions were reversible. GuHCl-induced denaturation was found to be cpn10 concentration dependent, in accord with a native heptamer to denatured monomer transition. In contrast, urea-induced denaturation was not cpn10 concentration dependent, suggesting that under these conditions cpn10 heptamers denature without dissociation. There were no indications of equilibrium intermediates, such as folded monomers, in either denaturant. The different cpn10 denatured states observed in high [GuHCl] and high [urea] were supported by cross-linking experiments. Thermal denaturation revealed that monomer and heptamer reactions display the same enthalpy change (per monomer), whereas the entropy-increase is significantly larger for the heptamer. A thermodynamic cycle for oligomeric cpn10, combining chemical denaturation with the dissociation constant in absence of denaturant, shows that dissociated monomers are only marginally stable (3 kJ/mol). The thermodynamics for co-chaperonin stability appears conserved; therefore, instability of the monomer could be necessary to specify the native heptameric structure. PMID:11152122

  19. The Dynamic Conformational Cycle of the Group I Chaperonin C-Termini Revealed via Molecular Dynamics Simulation

    PubMed Central

    Dalton, Kevin M.; Frydman, Judith; Pande, Vijay S.

    2015-01-01

    Chaperonins are large ring shaped oligomers that facilitate protein folding by encapsulation within a central cavity. All chaperonins possess flexible C-termini which protrude from the equatorial domain of each subunit into the central cavity. Biochemical evidence suggests that the termini play an important role in the allosteric regulation of the ATPase cycle, in substrate folding and in complex assembly and stability. Despite the tremendous wealth of structural data available for numerous orthologous chaperonins, little structural information is available regarding the residues within the C-terminus. Herein, molecular dynamics simulations are presented which localize the termini throughout the nucleotide cycle of the group I chaperonin, GroE, from Escherichia coli. The simulation results predict that the termini undergo a heretofore unappreciated conformational cycle which is coupled to the nucleotide state of the enzyme. As such, these results have profound implications for the mechanism by which GroE utilizes nucleotide and folds client proteins. PMID:25822285

  20. The dynamic conformational cycle of the group I chaperonin C-termini revealed via molecular dynamics simulation.

    PubMed

    Dalton, Kevin M; Frydman, Judith; Pande, Vijay S

    2015-01-01

    Chaperonins are large ring shaped oligomers that facilitate protein folding by encapsulation within a central cavity. All chaperonins possess flexible C-termini which protrude from the equatorial domain of each subunit into the central cavity. Biochemical evidence suggests that the termini play an important role in the allosteric regulation of the ATPase cycle, in substrate folding and in complex assembly and stability. Despite the tremendous wealth of structural data available for numerous orthologous chaperonins, little structural information is available regarding the residues within the C-terminus. Herein, molecular dynamics simulations are presented which localize the termini throughout the nucleotide cycle of the group I chaperonin, GroE, from Escherichia coli. The simulation results predict that the termini undergo a heretofore unappreciated conformational cycle which is coupled to the nucleotide state of the enzyme. As such, these results have profound implications for the mechanism by which GroE utilizes nucleotide and folds client proteins. PMID:25822285

  1. New GroEL-like chaperonin of bacteriophage OBP Pseudomonas fluorescens suppresses thermal protein aggregation in an ATP-dependent manner.

    PubMed

    Semenyuk, Pavel I; Orlov, Victor N; Sokolova, Olga S; Kurochkina, Lidia P

    2016-08-01

    Recently, we discovered and studied the first virus-encoded chaperonin of bacteriophage EL Pseudomonas aeruginosa, gene product (gp) 146. In the present study, we performed bioinformatics analysis of currently predicted GroEL-like proteins encoded by phage genomes in comparison with cellular and mitochondrial chaperonins. Putative phage chaperonins share a low similarity and do not form a monophyletic group; nevertheless, they are closer to bacterial chaperonins in the phylogenetic tree. Experimental investigation of putative GroEL-like chaperonin proteins has been continued by physicochemical and functional characterization of gp246 encoded by the genome of Pseudomonas fluorescens bacteriophage OBP. Unlike the more usual double-ring architecture of chaperonins, including the EL gp146, the recombinant gp246 produced by Escherichia coli cells has been purified as a single heptameric ring. It possesses ATPase activity and does not require a co-chaperonin for its function. In vitro experiments demonstrated that gp246 is able to suppress the thermal protein inactivation and aggregation in an ATP-dependent manner, thus indicating chaperonin function. Single-particle electron microscopy analysis revealed the different conformational states of OBP chaperonin, depending on the bound nucleotide. PMID:27247423

  2. The molecular architecture of the eukaryotic chaperonin TRiC/CCT

    PubMed Central

    Leitner, Alexander; Joachimiak, Lukasz A.; Bracher, Andreas; Mönkemeyer, Leonie; Walzthoeni, Thomas; Chen, Bryan; Pechmann, Sebastian; Holmes, Susan; Cong, Yao; Ma, Boxue; Ludtke, Steve; Chiu, Wah; Hartl, F. Ulrich; Aebersold, Ruedi; Frydman, Judith

    2012-01-01

    Summary TRiC/CCT is a highly conserved and essential chaperonin that uses ATP cycling to facilitate folding of approximately 10% of the eukaryotic proteome. This 1 MDa hetero-oligomeric complex consists of two stacked rings of eight paralogous subunits each. Previously proposed TRiC models differ substantially in their subunit arrangements and ring register. Here, we integrate chemical crosslinking, mass spectrometry and combinatorial modeling to reveal the definitive subunit arrangement of TRiC. In vivo disulfide mapping provided additional validation for the crosslinking-derived arrangement as the definitive TRiC topology. This subunit arrangement allowed the refinement of a structural model using existing X-ray diffraction data. The new structure explains all available crosslink experiments, provides a rationale for previously unexplained structural features and reveals a surprising asymmetry of charges within the chaperonin folding chamber. PMID:22503819

  3. Circular Permutation of a Chaperonin Protein: Biophysics and Application to Nanotechnology

    NASA Technical Reports Server (NTRS)

    Paavola, Chad; Chan, Suzanne; Li, Yi-Fen; McMillan, R. Andrew; Trent, Jonathan

    2004-01-01

    We have designed five circular permutants of a chaperonin protein derived from the hyperthermophilic organism Sulfolobus shibatae. These permuted proteins were expressed in E. coli and are well-folded. Furthermore, all the permutants assemble into 18-mer double rings of the same form as the wild-type protein. We characterized the thermodynamics of folding for each permutant by both guanidine denaturation and differential scanning calorimetry. We also examined the assembly of chaperonin rings into higher order structures that may be used as nanoscale templates. The results show that circular permutation can be used to tune the thermodynamic properties of a protein template as well as facilitating the fusion of peptides, binding proteins or enzymes onto nanostructured templates.

  4. An engineered chaperonin caging a guest protein: Structural insights and potential as a protein expression tool

    PubMed Central

    Furutani, Masahiro; Hata, Jun-Ichi; Shomura, Yasuhito; Itami, Keisuke; Yoshida, Takao; Izumoto, Yoshitaka; Togi, Akiko; Ideno, Akira; Yasunaga, Takuo; Miki, Kunio; Maruyama, Tadashi

    2005-01-01

    The structure of a chaperonin caging a substrate protein is not quite clear. We made engineered group II chaperonins fused with a guest protein and analyzed their structural and functional features. Thermococcus sp. KS-1 chaperonin α-subunit (TCP) which forms an eightfold symmetric double-ring structure was used. Expression plasmids were constructed which carried two or four TCP genes ligated head to tail in phase and a target protein gene at the 3′ end of the linked TCP genes. Electron microscopy showed that the expressed gene products with the molecular sizes of ~120 kDa (di-TCP) and ~230 kDa (tetra-TCP) formed double-ring complexes similar to those of wild-type TCP. The tetra-TCP retained ATPase activity and its thermostability was significantly higher than that of the wild type. A 260-kDa fusion protein of tetra-TCP and green fluorescent protein (GFP, 27 kDa) was able to form the double-ring complexes with green fluorescence. Image analyses indicated that the GFP moiety of tetra-TCP/GFP fusion protein was accommodated in the central cavity, and tetra-TCP/GFP formed the closed-form similar to that crystallographically resolved in group II chaperonins. Furthermore, it was suggested that caging GFP expanded the cavity around the bottom. Using this tetra-TCP fusion strategy, two virus structural proteins (21–25 kDa) toxic to host cells or two antibody fragments (25–36 kDa) prone to aggregate were well expressed in the soluble fraction of Escherichia coli. These fusion products also assembled to double-ring complexes, suggesting encapsulation of the guest proteins. The antibody fragments liberated by site-specific protease digestion exhibited ligand-binding activities. PMID:15659368

  5. Significance of the N-terminal domain for the function of chloroplast cpn20 chaperonin.

    PubMed

    Bonshtien, Anat L; Weiss, Celeste; Vitlin, Anna; Niv, Adina; Lorimer, George H; Azem, Abdussalam

    2007-02-16

    Chaperonins cpn60 and cpn10 are essential proteins involved in cellular protein folding. Plant chloroplasts contain a unique version of the cpn10 co-chaperonin, cpn20, which consists of two homologous cpn10-like domains (N-cpn20 and C-cpn20) that are connected by a short linker region. Although cpn20 seems to function like other single domain cpn10 oligomers, the structure and specific functions of the domains are not understood. We mutated amino acids in the "mobile loop" regions of N-cpn20, C-cpn20 or both: a highly conserved glycine, which was shown to be important for flexibility of the mobile loop, and a leucine residue shown to be involved in binding of co-chaperonin to chaperonin. The mutant proteins were purified and their oligomeric structure validated by gel filtration, native gel electrophoresis, and circular dichroism. Functional assays of protein refolding and inhibition of GroEL ATPase both showed (i) mutation of the conserved glycine reduced the activity of cpn20, whether in N-cpn20 (G32A) or C-cpn20 (G130A). The same mutation in the bacterial cpn10 (GroES G24A) had no effect on activity. (ii) Mutations in the highly conserved leucine of N-cpn20 (L35A) and in the corresponding L27A of GroES resulted in inactive protein. (iii) In contrast, mutant L133A, in which the conserved leucine of C-cpn20 was altered, retained 55% activity. We conclude that the structure of cpn20 is much more sensitive to alterations in the mobile loop than is the structure of GroES. Moreover, only N-cpn20 is necessary for activity of cpn20. However, full and efficient functioning requires both domains. PMID:17178727

  6. Surviving cancer without compromising aspirations.

    PubMed

    McGregor, Sandra

    2011-07-01

    This short paper is a reflection of how one person coped, survived and grew following numerous metastatic incidences over a 20 year period. Surviving cancer is a complex process but coping with the threat of regular recurrence has required a coping strategy that embraced the disease, set it aside and refused to compromise hopes, dreams and future life. Central to this personal journey has been the need to redefine normality, live with and set aside the fear of future metastases and death and find an answer and meaning in a changing biology, increased morbidity and possible mortality. This paper contends that not compromising the direction of travel and being able to focus on a career has ensured that survival was valuable and valued. A working environment in which students' problems have been immediate has produced different stressors. These have ultimately forced personal worries to be set aside, while living with cancer has become normal and accepted. PMID:21514884

  7. In vitro interactions of the aphid endosymbiotic SymL chaperonin with barley yellow dwarf virus.

    PubMed

    Filichkin, S A; Brumfield, S; Filichkin, T P; Young, M J

    1997-01-01

    Barley yellow dwarf virus (BYDV)-vector relationships suggest that there are specific interactions between BYDV virions and the aphid's cellular components. However, little is known about vector factors that mediate virion recognition, cellular trafficking, and accumulation within the aphid. Symbionins are molecular chaperonins produced by intracellular endosymbiotic bacteria and are the most abundant proteins found in aphids. To elucidate the potential role of symbionins in BYDV transmission, we have isolated and characterized two new symbionin symL genes encoded by the endosymbionts which are harbored by the BYDV aphid vectors Rhopalosiphum padi and Sitobion avenae. Endosymbiont symL-encoded proteins have extensive homology with the pea aphid SymL and Escherichia coli GroEL chaperonin. Recombinant and native SymL proteins can be assembled into oligomeric complexes which are similar to the GroEL oligomer. R. padi SymL protein demonstrates an in vitro binding affinity for BYDV and its recombinant readthrough polypeptide. In contrast to the R. padi SymL, the closely related GroEL does not exhibit a significant binding affinity either for BYDV or for its recombinant readthrough polypeptide. Comparative sequence analysis between SymL and GroEL was used to identify potential SymL-BYDV binding sites. Affinity binding of SymL to BYDV in vitro suggests a potential involvement of endosymbiotic chaperonins in interactions with virions during their trafficking through the aphid. PMID:8985385

  8. A Versatile Platform for Nanotechnology Based on Circular Permutation of a Chaperonin Protein

    NASA Technical Reports Server (NTRS)

    Paavola, Chad; McMillan, Andrew; Trent, Jonathan; Chan, Suzanne; Mazzarella, Kellen; Li, Yi-Fen

    2004-01-01

    A number of protein complexes have been developed as nanoscale templates. These templates can be functionalized using the peptide sequences that bind inorganic materials. However, it is difficult to integrate peptides into a specific position within a protein template. Integrating intact proteins with desirable binding or catalytic activities is an even greater challenge. We present a general method for modifying protein templates using circular permutation so that additional peptide sequence can be added in a wide variety of specific locations. Circular permutation is a reordering of the polypeptide chain such that the original termini are joined and new termini are created elsewhere in the protein. New sequence can be joined to the protein termini without perturbing the protein structure and with minimal limitation on the size and conformation of the added sequence. We have used this approach to modify a chaperonin protein template, placing termini at five different locations distributed across the surface of the protein complex. These permutants are competent to form the double-ring structures typical of chaperonin proteins. The permuted double-rings also form the same assemblies as the unmodified protein. We fused a fluorescent protein to two representative permutants and demonstrated that it assumes its active structure and does not interfere with assembly of chaperonin double-rings.

  9. On the assembly of dodecameric glutamine synthetase from stable chaperonin complexes.

    PubMed

    Fisher, M T

    1993-07-01

    For many in vitro protein-folding reactions, the fraction of correctly folded product declines as the initial protein concentration increases due primarily to misfolding and aggregation reactions. Under optimal conditions and in the presence of ATP, chaperonins (groEL and groES) enhanced the renaturation of dodecameric glutamine synthetase (GS) with yields of active enzyme between 75 and 85% of the original activity (Fisher, M.T. (1992) Biochemistry 31, 3955-3963). In spite of this enhancement, a concentration-dependent decline in recoverable activity was observed when increasing concentrations of unfolded GS were rapidly mixed with renaturation buffer containing a 2-fold molar excess (GS subunits:groEL oligomer) of chaperonins. When a stable groEL-GS complex, formed under optimal conditions, was concentrated 4-fold by centrifugal ultrafiltration prior to ATP addition, the amount of total active GS (percent of the original activity) recovered remained at optimal levels and no longer showed a concentration-dependent decline. The GS subunits that are initially bound and then released from groEL by ATP are assembly-competent. It is proposed that the subunits are no longer able to kinetically equilibrate with folding intermediates that misfold or aggregate. If a stable groEL-protein substrate complex can be amassed without loss of activity, this will facilitate studies on molecular aspects of chaperonin release mechanisms and oligomeric protein assembly. PMID:8100224

  10. The structural basis of substrate recognition by the eukaryotic chaperonin TRiC/CCT.

    PubMed

    Joachimiak, Lukasz A; Walzthoeni, Thomas; Liu, Corey W; Aebersold, Ruedi; Frydman, Judith

    2014-11-20

    The eukaryotic chaperonin TRiC (also called CCT) is the obligate chaperone for many essential proteins. TRiC is hetero-oligomeric, comprising two stacked rings of eight different subunits each. Subunit diversification from simpler archaeal chaperonins appears linked to proteome expansion. Here, we integrate structural, biophysical, and modeling approaches to identify the hitherto unknown substrate-binding site in TRiC and uncover the basis of substrate recognition. NMR and modeling provided a structural model of a chaperonin-substrate complex. Mutagenesis and crosslinking-mass spectrometry validated the identified substrate-binding interface and demonstrate that TRiC contacts full-length substrates combinatorially in a subunit-specific manner. The binding site of each subunit has a distinct, evolutionarily conserved pattern of polar and hydrophobic residues specifying recognition of discrete substrate motifs. The combinatorial recognition of polypeptides broadens the specificity of TRiC and may direct the topology of bound polypeptides along a productive folding trajectory, contributing to TRiC's unique ability to fold obligate substrates. PMID:25416944

  11. The structural basis of substrate recognition by the eukaryotic chaperonin TRiC/CCT

    PubMed Central

    Joachimiak, Lukasz A.; Walzthoeni, Thomas; Liu, Corey; Aebersold, Ruedi; Frydman, Judith

    2014-01-01

    Summary The eukaryotic chaperonin TRiC (also called CCT) is the obligate chaperone for many essential proteins. TRiC is hetero-oligomeric, comprising two stacked rings of eight different subunits each. Subunit diversification from simpler archaeal chaperonins appears linked to proteome expansion. Here, we integrate structural, biophysical and modeling approaches to identify the hitherto unknown substrate-binding site in TRiC and uncover the basis of substrate recognition. NMR and modeling provided a structural model of a chaperonin-substrate complex. Mutagenesis and crosslinking-mass spectrometry validated the identified substrate binding interface and demonstrate that TRiC contacts full-length substrates combinatorially in a subunit-specific manner. The binding site of each subunit has a distinct, evolutionarily conserved, pattern of polar and hydrophobic residues specifying recognition of discrete substrate motifs. The combinatorial recognition of polypeptides broadens the specificity of TRiC and may direct the topology of bound polypeptides along a productive folding trajectory, contributing to its unique ability to fold obligate substrates. PMID:25416944

  12. Contribution of the C-Terminal Region of a Group II Chaperonin to its Interaction with Prefoldin and Substrate Transfer.

    PubMed

    Zako, Tamotsu; Sahlan, Muhamad; Fujii, Sayaka; Yamamoto, Yohei Y; Tai, Phan The; Sakai, Kotaro; Maeda, Mizuo; Yohda, Masafumi

    2016-06-01

    Prefoldin is a molecular chaperone that captures an unfolded protein substrate and transfers it to a group II chaperonin. Previous studies have shown that the interaction sites for prefoldin are located in the helical protrusions of group II chaperonins. However, it does not exclude the possibility of the existence of other interaction sites. In this study, we constructed C-terminal truncation mutants of a group II chaperonin and examined the effects of these mutations on the chaperone's function and interaction with prefoldin. Whereas the mutants with up to 6 aa truncation from the C-terminus retained more than 90% chaperone activities for protecting citrate synthase from thermal aggregation and refolding of green fluorescent protein and isopropylmalate dehydrogenase, the truncation mutants showed decreased affinities for prefoldin. Consequently, the truncation mutants showed reduced transfer efficiency of the denatured substrate protein from prefoldin and subsequent chaperonin-dependent refolding. The results clearly show that the C-terminal region of group II chaperonins contributes to their interactions with prefoldin, the transfer of the substrate protein from prefoldin and its refolding. PMID:27079363

  13. Internal (His)6-tagging delivers a fully functional hetero-oligomeric class II chaperonin in high yield

    PubMed Central

    Paul, Danielle M.; Beuron, Fabienne; Sessions, Richard B.; Brancaccio, Andrea; Bigotti, Maria Giulia

    2016-01-01

    Group II chaperonins are ATP-ases indispensable for the folding of many proteins that play a crucial role in Archaea and Eukarya. They display a conserved two-ringed assembly enclosing an internal chamber where newly translated or misfolded polypeptides can fold to their native structure. They are mainly hexadecamers, with each eight-membered ring composed of one or two (in Archaea) or eight (in Eukarya) different subunits. A major recurring problem within group II chaperonin research, especially with the hetero-oligomeric forms, is to establish an efficient recombinant system for the expression of large amounts of wild-type as well as mutated variants. Herein we show how we can produce, in E. coli cells, unprecedented amounts of correctly assembled and active αβ-thermosome, the class II chaperonin from Thermoplasma acidophilum, by introducing a (His)6-tag within a loop in the α subunit of the complex. The specific location was identified via a rational approach and proved not to disturb the structure of the chaperonin, as demonstrated by size-exclusion chromatography, native gel electrophoresis and electron microscopy. Likewise, the tagged protein showed an ATP-ase activity and an ability to refold substrates identical to the wild type. This tagging strategy might be employed for the overexpression of other recombinant chaperonins. PMID:26856373

  14. 48 CFR 432.616 - Compromise actions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Compromise actions. 432.616 Section 432.616 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE GENERAL CONTRACTING REQUIREMENTS CONTRACT FINANCING Contract Debts 432.616 Compromise actions. Compromise of a...

  15. Intracellular localization of a group II chaperonin indicates a membrane-related function

    NASA Technical Reports Server (NTRS)

    Trent, Jonathan D.; Kagawa, Hiromi K.; Paavola, Chad D.; McMillan, R. Andrew; Howard, Jeanie; Jahnke, Linda; Lavin, Colleen; Embaye, Tsegereda; Henze, Christopher E.

    2003-01-01

    Chaperonins are protein complexes that are believed to function as part of a protein folding system in the cytoplasm of the cell. We observed, however, that the group II chaperonins known as rosettasomes in the hyperthermophilic archaeon Sulfolobus shibatae, are not cytoplasmic but membrane associated. This association was observed in cultures grown at 60 degrees C and 76 degrees C or heat-shocked at 85 degrees C by using immunofluorescence microscopy and in thick sections of rapidly frozen cells grown at 76 degrees C by using immunogold electron microscopy. We observed that increased abundance of rosettasomes after heat shock correlated with decreased membrane permeability at lethal temperature (92 degrees C). This change in permeability was not seen in cells heat-shocked in the presence of the amino acid analogue azetidine 2-carboxylic acid, indicating functional protein synthesis influences permeability. Azetidine experiments also indicated that observed heat-induced changes in lipid composition in S. shibatae could not account for changes in membrane permeability. Rosettasomes purified from cultures grown at 60 degrees C and 76 degrees C or heat-shocked at 85 degrees C bind to liposomes made from either the bipolar tetraether lipids of Sulfolobus or a variety of artificial lipid mixtures. The presence of rosettasomes did not significantly change the transition temperature of liposomes, as indicated by differential scanning calorimetry, or the proton permeability of liposomes, as indicated by pyranine fluorescence. We propose that these group II chaperonins function as a structural element in the natural membrane based on their intracellular location, the correlation between their functional abundance and membrane permeability, and their potential distribution on the membrane surface.

  16. Intracellular localization of a group II chaperonin indicates a membrane-related function

    PubMed Central

    Trent, Jonathan D.; Kagawa, Hiromi K.; Paavola, Chad D.; McMillan, R. Andrew; Howard, Jeanie; Jahnke, Linda; Lavin, Colleen; Embaye, Tsegereda; Henze, Christopher E.

    2003-01-01

    Chaperonins are protein complexes that are believed to function as part of a protein folding system in the cytoplasm of the cell. We observed, however, that the group II chaperonins known as rosettasomes in the hyperthermophilic archaeon Sulfolobus shibatae, are not cytoplasmic but membrane associated. This association was observed in cultures grown at 60°C and 76°C or heat-shocked at 85°C by using immunofluorescence microscopy and in thick sections of rapidly frozen cells grown at 76°C by using immunogold electron microscopy. We observed that increased abundance of rosettasomes after heat shock correlated with decreased membrane permeability at lethal temperature (92°C). This change in permeability was not seen in cells heat-shocked in the presence of the amino acid analogue azetidine 2-carboxylic acid, indicating functional protein synthesis influences permeability. Azetidine experiments also indicated that observed heat-induced changes in lipid composition in S. shibatae could not account for changes in membrane permeability. Rosettasomes purified from cultures grown at 60°C and 76°C or heat-shocked at 85°C bind to liposomes made from either the bipolar tetraether lipids of Sulfolobus or a variety of artificial lipid mixtures. The presence of rosettasomes did not significantly change the transition temperature of liposomes, as indicated by differential scanning calorimetry, or the proton permeability of liposomes, as indicated by pyranine fluorescence. We propose that these group II chaperonins function as a structural element in the natural membrane based on their intracellular location, the correlation between their functional abundance and membrane permeability, and their potential distribution on the membrane surface. PMID:14673104

  17. Dissection of the ATP-dependent conformational change cycle of a group II chaperonin.

    PubMed

    Nakagawa, Ayumi; Moriya, Kazuki; Arita, Mayuno; Yamamoto, Yohei; Kitamura, Kyotaro; Ishiguro, Naoki; Kanzaki, Taro; Oka, Toshihiko; Makabe, Koki; Kuwajima, Kunihiro; Yohda, Masafumi

    2014-01-23

    Group II chaperonin captures an unfolded protein while in its open conformation and then mediates the folding of the protein during ATP-driven conformational change cycle. In this study, we performed kinetic analyses of the group II chaperonin from a hyperthermophilic archaeon, Thermococcus sp. KS-1 (TKS1-Cpn), by stopped-flow fluorometry and stopped-flow small-angle X-ray scattering to reveal the reaction cycle. Two TKS1-Cpn variants containing a Trp residue at position 265 or position 56 exhibit nearly the same fluorescence kinetics induced by rapid mixing with ATP. Fluorescence started to increase immediately after the start of mixing and reached a maximum at 1-2s after mixing. Only in the presence of K(+) that a gradual decrease in fluorescence was observed after the initial peak. Similar results were obtained by stopped-flow small-angle X-ray scattering. A rapid fluorescence increase, which reflects nucleotide binding, was observed for the mutant containing a Trp residue near the ATP binding site (K485W), irrespective of the presence or absence of K(+). Without K(+), a small, rapid fluorescence decrease followed the initial increase, and then a gradual decrease was observed. In contrast, with K(+), a large, rapid fluorescence decrease occurred just after the initial increase, and then the fluorescence gradually increased. Finally, we observed ATP binding signal and also subtle conformational change in an ATPase-deficient mutant with K485W mutation. Based on these results, we propose a reaction cycle model for group II chaperonins. PMID:24120682

  18. A chaperonin as protein nanoreactor for atom-transfer radical polymerization.

    PubMed

    Renggli, Kasper; Nussbaumer, Martin G; Urbani, Raphael; Pfohl, Thomas; Bruns, Nico

    2014-01-27

    The group II chaperonin thermosome (THS) from the archaea Thermoplasma acidophilum is reported as nanoreactor for atom-transfer radical polymerization (ATRP). A copper catalyst was entrapped into the THS to confine the polymerization into this protein cage. THS possesses pores that are wide enough to release polymers into solution. The nanoreactor favorably influenced the polymerization of N-isopropyl acrylamide and poly(ethylene glycol)methylether acrylate. Narrowly dispersed polymers with polydispersity indices (PDIs) down to 1.06 were obtained in the protein nanoreactor, while control reactions with a globular protein-catalyst conjugate only yielded polymers with PDIs above 1.84. PMID:24459061

  19. Forensic Analysis of Compromised Computers

    NASA Technical Reports Server (NTRS)

    Wolfe, Thomas

    2004-01-01

    Directory Tree Analysis File Generator is a Practical Extraction and Reporting Language (PERL) script that simplifies and automates the collection of information for forensic analysis of compromised computer systems. During such an analysis, it is sometimes necessary to collect and analyze information about files on a specific directory tree. Directory Tree Analysis File Generator collects information of this type (except information about directories) and writes it to a text file. In particular, the script asks the user for the root of the directory tree to be processed, the name of the output file, and the number of subtree levels to process. The script then processes the directory tree and puts out the aforementioned text file. The format of the text file is designed to enable the submission of the file as input to a spreadsheet program, wherein the forensic analysis is performed. The analysis usually consists of sorting files and examination of such characteristics of files as ownership, time of creation, and time of most recent access, all of which characteristics are among the data included in the text file.

  20. Probing Water Density and Dynamics in the Chaperonin GroEL Cavity

    PubMed Central

    2015-01-01

    ATP-dependent binding of the chaperonin GroEL to its cofactor GroES forms a cavity in which encapsulated substrate proteins can fold in isolation from bulk solution. It has been suggested that folding in the cavity may differ from that in bulk solution owing to steric confinement, interactions with the cavity walls, and differences between the properties of cavity-confined and bulk water. However, experimental data regarding the cavity-confined water are lacking. Here, we report measurements of water density and diffusion dynamics in the vicinity of a spin label attached to a cysteine in the Tyr71 → Cys GroES mutant obtained using two magnetic resonance techniques: electron-spin echo envelope modulation and Overhauser dynamic nuclear polarization. Residue 71 in GroES is fully exposed to bulk water in free GroES and to confined water within the cavity of the GroEL–GroES complex. Our data show that water density and translational dynamics in the vicinity of the label do not change upon complex formation, thus indicating that bulk water-exposed and cavity-confined GroES surface water share similar properties. Interestingly, the diffusion dynamics of water near the GroES surface are found to be unusually fast relative to other protein surfaces studied. The implications of these findings for chaperonin-assisted folding mechanisms are discussed. PMID:24888581

  1. Chaperonin GroEL-GroES Functions as both Alternating and Non-Alternating Engines.

    PubMed

    Yamamoto, Daisuke; Ando, Toshio

    2016-07-31

    A double ring-shaped GroEL consisting of 14 ATPase subunits assists protein folding, together with co-chaperonin GroES. The dynamic GroEL-GroES interaction is actively involved in the chaperonin reaction. Therefore, revealing this dynamic interaction is a key to understanding the operation principle of GroEL. Nevertheless, how this interaction proceeds in the reaction cycle has long been controversial. Here, we directly imaged GroEL-GroES interaction in the presence of disulfide-reduced α-lactalbumin as a substrate protein using high-speed atomic force microscopy. This real-time imaging revealed the occurrence of primary, symmetric GroEL:GroES2 and secondary, asymmetric GroEL:GroES1 complexes. Remarkably, the reaction was observed to often branch into main and side pathways. In the main pathway, alternate binding and release of GroES occurs at the two rings, indicating tight cooperation between the two rings. In the side pathway, however, this cooperation is disrupted, resulting in the interruption of alternating rhythm. From various properties observed for both pathways, we provide mechanistic insight into the alternate and non-alternate operations of the two-engine system. PMID:27393305

  2. A Chaperonin Subunit with Unique Structures Is Essential for Folding of a Specific Substrate

    PubMed Central

    Peng, Lianwei; Fukao, Yoichiro; Myouga, Fumiyoshi; Motohashi, Reiko; Shinozaki, Kazuo; Shikanai, Toshiharu

    2011-01-01

    Type I chaperonins are large, double-ring complexes present in bacteria (GroEL), mitochondria (Hsp60), and chloroplasts (Cpn60), which are involved in mediating the folding of newly synthesized, translocated, or stress-denatured proteins. In Escherichia coli, GroEL comprises 14 identical subunits and has been exquisitely optimized to fold its broad range of substrates. However, multiple Cpn60 subunits with different expression profiles have evolved in chloroplasts. Here, we show that, in Arabidopsis thaliana, the minor subunit Cpn60β4 forms a heterooligomeric Cpn60 complex with Cpn60α1 and Cpn60β1–β3 and is specifically required for the folding of NdhH, a subunit of the chloroplast NADH dehydrogenase-like complex (NDH). Other Cpn60β subunits cannot complement the function of Cpn60β4. Furthermore, the unique C-terminus of Cpn60β4 is required for the full activity of the unique Cpn60 complex containing Cpn60β4 for folding of NdhH. Our findings suggest that this unusual kind of subunit enables the Cpn60 complex to assist the folding of some particular substrates, whereas other dominant Cpn60 subunits maintain a housekeeping chaperonin function by facilitating the folding of other obligate substrates. PMID:21483722

  3. Chaperonin GroEL/GroES Over-Expression Promotes Aminoglycoside Resistance and Reduces Drug Susceptibilities in Escherichia coli Following Exposure to Sublethal Aminoglycoside Doses

    PubMed Central

    Goltermann, Lise; Sarusie, Menachem V.; Bentin, Thomas

    2016-01-01

    Antibiotic resistance is an increasing challenge to modern healthcare. Aminoglycoside antibiotics cause translation corruption and protein misfolding and aggregation in Escherichia coli. We previously showed that chaperonin GroEL/GroES depletion and over-expression sensitize and promote short-term tolerance, respectively, to this drug class. Here, we show that chaperonin GroEL/GroES over-expression accelerates acquisition of streptomycin resistance and reduces susceptibility to several other antibiotics following sub-lethal streptomycin antibiotic exposure. Chaperonin buffering could provide a novel mechanism for emergence of antibiotic resistance. PMID:26858694

  4. Chaperonin GroEL/GroES Over-Expression Promotes Aminoglycoside Resistance and Reduces Drug Susceptibilities in Escherichia coli Following Exposure to Sublethal Aminoglycoside Doses.

    PubMed

    Goltermann, Lise; Sarusie, Menachem V; Bentin, Thomas

    2015-01-01

    Antibiotic resistance is an increasing challenge to modern healthcare. Aminoglycoside antibiotics cause translation corruption and protein misfolding and aggregation in Escherichia coli. We previously showed that chaperonin GroEL/GroES depletion and over-expression sensitize and promote short-term tolerance, respectively, to this drug class. Here, we show that chaperonin GroEL/GroES over-expression accelerates acquisition of streptomycin resistance and reduces susceptibility to several other antibiotics following sub-lethal streptomycin antibiotic exposure. Chaperonin buffering could provide a novel mechanism for emergence of antibiotic resistance. PMID:26858694

  5. Integrity and compromise in nursing ethics.

    PubMed

    Winslow, B J; Winslow, G R

    1991-06-01

    Nurses are often caught in the middle of what appear to be intractable moral conflicts. For such times, the function and limits of moral compromise need to be explored. Compromise is compatible with moral integrity if a number of conditions are met. Among these are the sharing of a moral language, mutual respect on the part of those who differ, acknowledgement of factual and moral complexities, and recognition of limits to compromise. Nurses are in a position uniquely suited to leadership in fostering an environment that makes compromise with integrity possible. PMID:1880466

  6. 49 CFR 1503.425 - Compromise orders.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 9 2014-10-01 2014-10-01 false Compromise orders. 1503.425 Section 1503.425... Assessment of Civil Penalties by TSA § 1503.425 Compromise orders. (a) Issuance. At any time before the issuance of an Order Assessing Civil Penalty under this subpart, an agency attorney and a person subject...

  7. 49 CFR 1503.425 - Compromise orders.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 9 2011-10-01 2011-10-01 false Compromise orders. 1503.425 Section 1503.425... Assessment of Civil Penalties by TSA § 1503.425 Compromise orders. (a) Issuance. At any time before the issuance of an Order Assessing Civil Penalty under this subpart, an agency attorney and a person subject...

  8. 48 CFR 32.610 - Compromising debts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... REQUIREMENTS CONTRACT FINANCING Contract Debts 32.610 Compromising debts. For debts under $100,000, excluding interest, the designated agency official may compromise the debt pursuant to the Federal Claims Collection Standards (31 CFR part 902) and agency regulations. Unless specifically authorized by agency...

  9. 48 CFR 1432.610 - Compromising debts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Compromising debts. 1432.610 Section 1432.610 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR GENERAL CONTRACTING REQUIREMENTS CONTRACT FINANCING Contract Debts 1432.610 Compromising debts. The CO may...

  10. 26 CFR 301.7122-1 - Compromises.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Secretary may, at the Secretary's discretion, compromise any civil or criminal liability arising under the internal revenue laws prior to reference of a case involving such a liability to the Department of Justice for prosecution or defense. (2) An agreement to compromise may relate to a civil or criminal...

  11. Contribution of the Type II Chaperonin, TRiC/CCT, to Oncogenesis

    PubMed Central

    Roh, Soung-Hun; Kasembeli, Moses; Bakthavatsalam, Deenadayalan; Chiu, Wah; Tweardy, David J.

    2015-01-01

    The folding of newly synthesized proteins and the maintenance of pre-existing proteins are essential in sustaining a living cell. A network of molecular chaperones tightly guides the folding, intracellular localization, and proteolytic turnover of proteins. Many of the key regulators of cell growth and differentiation have been identified as clients of molecular chaperones, which implies that chaperones are potential mediators of oncogenesis. In this review, we briefly provide an overview of the role of chaperones, including HSP70 and HSP90, in cancer. We further summarize and highlight the emerging the role of chaperonin TRiC (T-complex protein-1 ring complex, also known as CCT) in the development and progression of cancer mediated through its critical interactions with oncogenic clients that modulate growth deregulation, apoptosis, and genome instability in cancer cells. Elucidation of how TRiC modulates the folding and function of oncogenic clients will provide strategies for developing novel cancer therapies. PMID:26561808

  12. The purified and recombinant Legionella pneumophila chaperonin alters mitochondrial trafficking and microfilament organization.

    PubMed

    Chong, Audrey; Lima, Celia A; Allan, David S; Nasrallah, Gheyath K; Garduño, Rafael A

    2009-11-01

    A portion of the total cellular pool of the Legionella pneumophila chaperonin, HtpB, is found on the bacterial cell surface, where it can mediate invasion of nonphagocytic cells. HtpB continues to be abundantly produced and released by internalized L. pneumophila and may thus have postinvasion functions. We used here two functional models (protein-coated beads and expression of recombinant proteins in CHO cells) to investigate the competence of HtpB in mimicking early intracellular trafficking events of L. pneumophila, including the recruitment of mitochondria, cytoskeletal alterations, the inhibition of phagosome-lysosome fusion, and association with the endoplasmic reticulum. Microscopy and flow cytometry studies indicated that HtpB-coated beads recruited mitochondria in CHO cells and U937-derived macrophages and induced transient changes in the organization of actin microfilaments in CHO cells. Ectopic expression of HtpB in the cytoplasm of transfected CHO cells also led to modifications in actin microfilaments similar to those produced by HtpB-coated beads but did not change the distribution of mitochondria. Association of phagosomes containing HtpB-coated beads with the endoplasmic reticulum was not consistently detected by either fluorescence or electron microscopy studies, and only a modest delay in the fusion of TrOv-labeled lysosomes with phagosomes containing HtpB-coated beads was observed. HtpB is the first Legionella protein and the first chaperonin shown to, by means of our functional models, induce mitochondrial recruitment and microfilament rearrangements, two postinternalization events that typify the early trafficking of virulent L. pneumophila. PMID:19687203

  13. Enhanced expression of soluble human papillomavirus L1 through coexpression of molecular chaperonin in Escherichia coli.

    PubMed

    Pan, Dong; Zha, Xiao; Yu, Xianghui; Wu, Yuqing

    2016-04-01

    The major recombinant capsid protein L1 of human papillomavirus (HPV) is widely used to produce HPV prophylactic vaccines. However, the quality of soluble and active expression of L1 in Escherichia coli was below the required amount. Coexpression with the chaperonin GroEL/ES enhanced L1 expression. Overexpressing GroEL/ES increased the soluble expression level of glutathione S-transferase-fused L1 (GST-L1) by approximately ∼3 fold. The yield of HPV type 16 L1 pentamer (L1-p) was ∼2 fold higher than that in a single expression system after purification through size-exclusion chromatograph. The expression and purification conditions were then optimized. The yield of L1-p was enhanced by ∼5 fold, and those of HPV types 18 and 58 L1-p increased by ∼3 and ∼2 folds, respectively, compared with that in the single expression system. Coexpressing the mono-site mutant HPV16 L1 L469A with GroEL/ES increased L1-p yield by ∼7 fold compared with strains expressing the wild-type L1 gene. L1-p was then characterized using circular dichroism spectra, UV-vis cloud point, dynamic light scattering and transmission electron microscope analyses. Results indicated that the conformation and biological characteristics of L1-p were identical to that of native L1. Hence, overexpressing chaperonin in E. coli can increase the expression level of GST-L1 and L1-p production after purification. This finding may contribute to the development of a platform for prophylactic HPV vaccines. PMID:26732286

  14. A Two-step Mechanism for the Folding of Actin by the Yeast Cytosolic Chaperonin

    PubMed Central

    Stuart, Sarah F.; Leatherbarrow, Robin J.; Willison, Keith R.

    2011-01-01

    Actin requires the chaperonin containing TCP1 (CCT), a hexadecameric ATPase essential for cell viability in eukaryotes, to fold to its native state. Following binding of unfolded actin to CCT, the cavity of the chaperone closes and actin is folded and released in an ATP-dependent folding cycle. In yeast, CCT forms a ternary complex with the phosducin-like protein PLP2p to fold actin, and together they can return nascent or chemically denatured actin to its native state in a pure in vitro folding assay. The complexity of the CCT-actin system makes the study of the actin folding mechanism technically challenging. We have established a novel spectroscopic assay through selectively labeling the C terminus of yeast actin with acrylodan and observe significant changes in the acrylodan fluorescence emission spectrum as actin is chemically unfolded and then refolded by the chaperonin. The variation in the polarity of the environment surrounding the fluorescent probe during the unfolding/folding processes has allowed us to monitor actin as it folds on CCT. The rate of actin folding at a range of temperatures and ATP concentrations has been determined for both wild type CCT and a mutant CCT, CCT4anc2, defective in folding actin in vivo. Binding of the non-hydrolysable ATP analog adenosine 5′-(β,γ-imino)triphosphate to the ternary complex leads to 3-fold faster release of actin from CCT following addition of ATP, suggesting a two-step folding process with a conformational change occurring upon closure of the cavity and a subsequent final folding step involving packing of the C terminus to the native-like state. PMID:21056978

  15. Group II archaeal chaperonin recognition of partially folded human γD-crystallin mutants.

    PubMed

    Sergeeva, Oksana A; Yang, Jingkun; King, Jonathan A; Knee, Kelly M

    2014-06-01

    The features in partially folded intermediates that allow the group II chaperonins to distinguish partially folded from native states remain unclear. The archaeal group II chaperonin from Methanococcus Mauripaludis (Mm-Cpn) assists the in vitro refolding of the well-characterized β-sheet lens protein human γD-crystallin (HγD-Crys). The domain interface and buried cores of this Greek key conformation include side chains, which might be exposed in partially folded intermediates. We sought to assess whether particular features buried in the native state, but absent from the native protein surface, might serve as recognition signals. The features tested were (a) paired aromatic side chains, (b) side chains in the interface between the duplicated domains of HγD-Crys, and (c) side chains in the buried core which result in congenital cataract when substituted. We tested the Mm-Cpn suppression of aggregation of these HγD-Crys mutants upon dilution out of denaturant. Mm-Cpn was capable of suppressing the off-pathway aggregation of the three classes of mutants indicating that the buried residues were not recognition signals. In fact, Mm-Cpn recognized the HγD-Crys mutants better than (wild-type) WT and refolded most mutant HγD-Crys to levels twice that of WT HγD-Crys. This presumably represents the increased population or longer lifetimes of the partially folded intermediates of the mutant proteins. The results suggest that Mm-Cpn does not recognize the features of HγD-Crys tested-paired aromatics, exposed domain interface, or destabilized core-but rather recognizes other features of the partially folded β-sheet conformation that are absent or inaccessible in the native state of HγD-Crys. PMID:24615724

  16. Group II archaeal chaperonin recognition of partially folded human γD-crystallin mutants

    PubMed Central

    Sergeeva, Oksana A; Yang, Jingkun; King, Jonathan A; Knee, Kelly M

    2014-01-01

    The features in partially folded intermediates that allow the group II chaperonins to distinguish partially folded from native states remain unclear. The archaeal group II chaperonin from Methanococcus Mauripaludis (Mm-Cpn) assists the in vitro refolding of the well-characterized β-sheet lens protein human γD-crystallin (HγD-Crys). The domain interface and buried cores of this Greek key conformation include side chains, which might be exposed in partially folded intermediates. We sought to assess whether particular features buried in the native state, but absent from the native protein surface, might serve as recognition signals. The features tested were (a) paired aromatic side chains, (b) side chains in the interface between the duplicated domains of HγD-Crys, and (c) side chains in the buried core which result in congenital cataract when substituted. We tested the Mm-Cpn suppression of aggregation of these HγD-Crys mutants upon dilution out of denaturant. Mm-Cpn was capable of suppressing the off-pathway aggregation of the three classes of mutants indicating that the buried residues were not recognition signals. In fact, Mm-Cpn recognized the HγD-Crys mutants better than (wild-type) WT and refolded most mutant HγD-Crys to levels twice that of WT HγD-Crys. This presumably represents the increased population or longer lifetimes of the partially folded intermediates of the mutant proteins. The results suggest that Mm-Cpn does not recognize the features of HγD-Crys tested—paired aromatics, exposed domain interface, or destabilized core—but rather recognizes other features of the partially folded β-sheet conformation that are absent or inaccessible in the native state of HγD-Crys. PMID:24615724

  17. Functional characterization of an archaeal GroEL/GroES chaperonin system: significance of substrate encapsulation.

    PubMed

    Figueiredo, Luis; Klunker, Daniel; Ang, Debbie; Naylor, Dean J; Kerner, Michael J; Georgopoulos, Costa; Hartl, F Ulrich; Hayer-Hartl, Manajit

    2004-01-01

    In all three kingdoms of life chaperonins assist the folding of a range of newly synthesized proteins. As shown recently, Archaea of the genus Methanosarcina contain both group I (GroEL/GroES) and group II (thermosome) chaperonins in the cytosol. Here we report on a detailed functional analysis of the archaeal GroEL/GroES system of Methanosarcina mazei (Mm) in comparison to its bacterial counterpart from Escherichia coli (Ec). We find that the groESgroEL operon of M. mazei is unable to functionally replace groESgroEL in E. coli. However, the MmGroES protein can largely complement a mutant EcGroES protein in vivo. The ATPase rate of MmGroEL is very low and the dissociation of MmGroES from MmGroEL is 15 times slower than for the EcGroEL/GroES system. This slow ATPase cycle results in a prolonged enclosure time for model substrate proteins, such as rhodanese, in the MmGroEL:GroES folding cage before their release into the medium. Interestingly, optimal functionality of MmGroEL/GroES and its ability to encapsulate larger proteins, such as malate dehydrogenase, requires the presence of ammonium sulfate in vitro. In the absence of ammonium sulfate, malate dehydrogenase fails to be encapsulated by GroES and rather cycles on and off the GroEL trans ring in a non-productive reaction. These results indicate that the archaeal GroEL/GroES system has preserved the basic encapsulation mechanism of bacterial GroEL and suggest that it has adjusted the length of its reaction cycle to the slower growth rates of Archaea. Additionally, the release of only the folded protein from the GroEL/GroES cage may prevent adverse interactions of the GroEL substrates with the thermosome, which is not normally located within the same compartment. PMID:14576149

  18. Simulation of the shape of chaperonins using the small-angle x-ray scattering curves and torus form factor

    SciTech Connect

    Amarantov, S. V.; Naletova, I. N.; Kurochkina, L. P.

    2011-08-15

    The inverse scattering problem has been solved for protein complexes whose surfaces can be described by a set of the simplest doubly connected surfaces in the uniform approximation (a scattering potential inside the molecule is a constant). Solutions of two proteins-well-known GroEL bacterial chaperonin and poor-studied bacteriophage chaperonin, which is a product of 146 gene (gp146)-were taken for the experiment. The shapes of protein complexes have been efficiently reconstructed from the experimental scattering curves. The shell method, the method of the rotation of amino acid sequences with the use of the form factor of an amino acid, and the method of seeking the model parameters of a protein complex with the preliminarily obtained form factor of the model have been used to reconstruct the shape of these particles.

  19. GroEL/ES Chaperonin Modulates the Mechanism and Accelerates the Rate of TIM-Barrel Domain Folding

    PubMed Central

    Bracher, Andreas; Engen, John R.; Hayer-Hartl, Manajit; Hartl, F. Ulrich

    2014-01-01

    SUMMARY The GroEL/ES chaperonin system functions as a protein folding cage. Many obligate substrates of GroEL share the (βα)8 TIM-barrel fold, but how the chaperonin promotes folding of these proteins is not known. Here we analyzed the folding of DapA at peptide resolution using hydrogen/deuterium exchange and mass spectrometry. During spontaneous folding, all elements of the DapA TIM-barrel acquire structure simultaneously, in a process associated with a long search time. In contrast, GroEL/ES accelerates folding more than 30-fold by catalyzing segmental structure formation in the TIM-barrel. Segmental structure formation is also observed during the fast spontaneous folding of a structural homolog of DapA from a bacterium that lacks GroEL/ES. Thus, chaperonin-independence correlates with folding properties otherwise enforced by protein confinement in the GroEL/ES cage. We suggest that folding catalysis by GroEL/ES is required by a set of proteins to reach native state at a biologically relevant time-scale, avoiding aggregation or degradation. PMID:24813614

  20. [Effect of ADP and GroES on interaction of molecular chaperonin GroEL with non-native lysozyme].

    PubMed

    Marchenko, N Iu; Marchenkov, V V; Kotova, N V; Semisotnov, G V; Bulankina, N I; Kaliman, P A

    2003-01-01

    The interaction of the molecular chaperonin GroEL with fluorescein-labeled lysozyme in the presence of high concentrations of thiol reagent--dithiothreitol (DTT) has been studied. In case of high concentrations of DTT lysozyme loses the native conformation due to the disruption of the intramolecular disulfide bonds stabilizing its structure and effectively aggregates. It has been shown that in the presence of high concentrations of DTT and two-fold molar excess of GroEL the lysozyme tightly interacts with GroEL that essentially decreases the efficiency of its aggregation. The addition of ADP to the complex of GroEL with nonnative lysozyme noticeably decreases the interaction of the chaperonin with nonnative protein target resulting in some increase of the efficiency of its aggregation. However, the addition of the co-chaperonin GroES together with ADP (i.e. the formation of the complex of GroEL with GroES) leads to drastic weakness of the interaction of GroEL with nonnative lysozyme and the efficiency of its aggregation becomes comparable with that in the absence of GroEL. PMID:14577157

  1. Chaperonin Cofactors, Cpn10 and Cpn20, of Green Algae and Plants Function as Hetero-oligomeric Ring Complexes*♦

    PubMed Central

    Tsai, Yi-Chin C.; Mueller-Cajar, Oliver; Saschenbrecker, Sandra; Hartl, F. Ulrich; Hayer-Hartl, Manajit

    2012-01-01

    The chloroplast chaperonin system of plants and green algae is a curiosity as both the chaperonin cage and its lid are encoded by multiple genes, in contrast to the single genes encoding the two components of the bacterial and mitochondrial systems. In the green alga Chlamydomonas reinhardtii (Cr), three genes encode chaperonin cofactors, with cpn10 encoding a single ∼10-kDa domain and cpn20 and cpn23 encoding tandem cpn10 domains. Here, we characterized the functional interaction of these proteins with the Escherichia coli chaperonin, GroEL, which normally cooperates with GroES, a heptamer of ∼10-kDa subunits. The C. reinhardtii cofactor proteins alone were all unable to assist GroEL-mediated refolding of bacterial ribulose-bisphosphate carboxylase/oxygenase but gained this ability when CrCpn20 and/or CrCpn23 was combined with CrCpn10. Native mass spectrometry indicated the formation of hetero-oligomeric species, consisting of seven ∼10-kDa domains. The cofactor “heptamers” interacted with GroEL and encapsulated substrate protein in a nucleotide-dependent manner. Different hetero-oligomer arrangements, generated by constructing cofactor concatamers, indicated a preferential heptamer configuration for the functional CrCpn10-CrCpn23 complex. Formation of heptamer Cpn10/Cpn20 hetero-oligomers was also observed with the Arabidopsis thaliana (At) cofactors, which functioned with the chloroplast chaperonin, AtCpn60α7β7. It appears that hetero-oligomer formation occurs more generally for chloroplast chaperonin cofactors, perhaps adapting the chaperonin system for the folding of specific client proteins. PMID:22518837

  2. 39 CFR 931.1 - Compromise of obligations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Compromise of obligations. 931.1 Section 931.1 Postal Service UNITED STATES POSTAL SERVICE PROCEDURES RULES OF PROCEDURE GOVERNING THE COMPROMISE OF OBLIGATIONS § 931.1 Compromise of obligations. Any proposition of compromise shall be submitted in writing, and the amount offered in compromise...

  3. Vascular Compromise from Soft Tissue Augmentation

    PubMed Central

    Humphrey, Shannon; Carruthers, Jean D.A.; Carruthers, Alastair

    2014-01-01

    The popularity of soft tissue fillers is, in part, due to their favorable side-effect profile. However, serious complications can occur. The authors describe their extensive clinical experience with soft-tissue augmentation and the rare complication of vascular compromise, which can lead to necrosis and scarring. Over a 10-year period between January 2003 and January 2013, the authors observed a total of 12 cases of vascular compromise. Eight patients in their clinical practice showed evidence of vascular compromise out of a total of 14,355 filler injections (0.05%). In addition, four patients treated with an experimental particulate filler had vascular complications. All cases were examined for filler type, location of complication, risk factors, treatment, and outcomes. Although treatment plans differed for each patient in their series, all cases of vascular compromise resolved fully. The authors believe that an office-based protocol for both immediate and ongoing care—including a thorough individualized assessment and treatment plan for each patient—is critical to timely and effective resolution of side effects. They propose key recommendations for the prevention and management of vascular compromise to improve patient outcomes and reduce the risk of permanent complications. PMID:25276276

  4. The htpAB operon of Legionella pneumophila cannot be deleted in the presence of the groE chaperonin operon of Escherichia coli.

    PubMed

    Nasrallah, Gheyath K; Gagnon, Elizabeth; Orton, Dennis J; Garduño, Rafael A

    2011-11-01

    HtpB, the chaperonin of the intracellular bacterial pathogen Legionella pneumophila , displays several virulence-related functions in vitro. To confirm HtpB's role in vivo, host infections with an htpB deletion mutant would be required. However, we previously reported that the htpAB operon (encoding co-chaperonin and chaperonin) is essential. We attempted here to delete htpAB in a L. pneumophila strain carrying the groE operon (encoding the Escherichia coli co-chaperonin and chaperonin). The groE operon was inserted into the chromosome of L. pneumophila Lp02, and then allelic replacement of htpAB with a gentamicin resistance cassette was attempted. Although numerous potential postallelic replacement transformants showed a correct selection phenotype, we still detected htpAB by PCR and full-size HtpB by immunoblot. Southern blot and PCR analysis indicated that the gentamicin resistance cassette had apparently integrated in a duplicated htpAB region. However, we showed by Southern blot that strain Lp02, and the Lp02 derivative carrying the groE operon, have only one copy of htpAB. These results confirmed that the htpAB operon cannot be deleted, not even in the presence of the groE operon, and suggested that attempts to delete htpAB under strong phenotypic selection result in aberrant genetic recombinations that could involve duplication of the htpAB locus. PMID:22029459

  5. Probing the Kinetic Stabilities of Friedreich’s Ataxia Clinical Variants Using a Solid Phase GroEL Chaperonin Capture Platform

    PubMed Central

    Correia, Ana R.; Naik, Subhashchandra; Fisher, Mark T.; Gomes, Cláudio M.

    2014-01-01

    Numerous human diseases are caused by protein folding defects where the protein may become more susceptible to degradation or aggregation. Aberrant protein folding can affect the kinetic stability of the proteins even if these proteins appear to be soluble in vivo. Experimental discrimination between functional properly folded and misfolded nonfunctional conformers is not always straightforward at near physiological conditions. The differences in the kinetic behavior of two initially folded frataxin clinical variants were examined using a high affinity chaperonin kinetic trap approach at 25 °C. The kinetically stable wild type frataxin (FXN) shows no visible partitioning onto the chaperonin. In contrast, the clinical variants FXN-p.Asp122Tyr and FXN-p.Ile154Phe kinetically populate partial folded forms that tightly bind the GroEL chaperonin platform. The initially soluble FXN-p.Ile154Phe variant partitions onto GroEL more rapidly and is more kinetically liable. These differences in kinetic stability were confirmed using differential scanning fluorimetry. The kinetic and aggregation stability differences of these variants may lead to the distinct functional impairments described in Friedreich’s ataxia, the neurodegenerative disease associated to frataxin functional deficiency. This chaperonin platform approach may be useful for identifying small molecule stabilizers since stabilizing ligands to frataxin variants should lead to a concomitant decrease in chaperonin binding. PMID:25333765

  6. Modeling the Dynamics of Compromised Networks

    SciTech Connect

    Soper, B; Merl, D M

    2011-09-12

    Accurate predictive models of compromised networks would contribute greatly to improving the effectiveness and efficiency of the detection and control of network attacks. Compartmental epidemiological models have been applied to modeling attack vectors such as viruses and worms. We extend the application of these models to capture a wider class of dynamics applicable to cyber security. By making basic assumptions regarding network topology we use multi-group epidemiological models and reaction rate kinetics to model the stochastic evolution of a compromised network. The Gillespie Algorithm is used to run simulations under a worst case scenario in which the intruder follows the basic connection rates of network traffic as a method of obfuscation.

  7. Ancient allelism at the cytosolic chaperonin-alpha-encoding gene of the zebrafish.

    PubMed Central

    Takami, K; Figueroa, F; Mayer, W E; Klein, J

    2000-01-01

    The T-complex protein 1, TCP1, gene codes for the CCT-alpha subunit of the group II chaperonins. The gene was first described in the house mouse, in which it is closely linked to the T locus at a distance of approximately 11 cM from the Mhc. In the zebrafish, Danio rerio, in which the T homolog is linked to the class I Mhc loci, the TCP1 locus segregates independently of both the T and the Mhc loci. Despite its conservation between species, the zebrafish TCP1 locus is highly polymorphic. In a sample of 15 individuals and the screening of a cDNA library, 12 different alleles were found, and some of the allelic pairs were found to differ by up to nine nucleotides in a 275-bp-long stretch of sequence. The substitutions occur in both translated and untranslated regions, but in the former they occur predominantly at synonymous codon sites. Phylogenetically, the alleles fall into two groups distinguished also by the presence or absence of a 10-bp insertion/deletion in the 3' untranslated region. The two groups may have diverged as long as 3.5 mya, and the polymorphic differences may have accumulated by genetic drift in geographically isolated populations. PMID:10628990

  8. Modulation of STAT3 Folding and Function by TRiC/CCT Chaperonin

    PubMed Central

    Kasembeli, Moses; Lau, Wilson Chun Yu; Roh, Soung-Hun; Eckols, T. Kris; Frydman, Judith; Chiu, Wah; Tweardy, David J.

    2014-01-01

    Signal transducer and activator of transcription 3 (Stat3) transduces signals of many peptide hormones from the cell surface to the nucleus and functions as an oncoprotein in many types of cancers, yet little is known about how it achieves its native folded state within the cell. Here we show that Stat3 is a novel substrate of the ring-shaped hetero-oligomeric eukaryotic chaperonin, TRiC/CCT, which contributes to its biosynthesis and activity in vitro and in vivo. TRiC binding to Stat3 was mediated, at least in part, by TRiC subunit CCT3. Stat3 binding to TRiC mapped predominantly to the β-strand rich, DNA-binding domain of Stat3. Notably, enhancing Stat3 binding to TRiC by engineering an additional TRiC-binding domain from the von Hippel-Lindau protein (vTBD), at the N-terminus of Stat3, further increased its affinity for TRiC as well as its function, as determined by Stat3's ability to bind to its phosphotyrosyl-peptide ligand, an interaction critical for Stat3 activation. Thus, Stat3 levels and function are regulated by TRiC and can be modulated by manipulating its interaction with TRiC. PMID:24756126

  9. GroE chaperonins assisted functional expression of bacterial enzymes in Saccharomyces cerevisiae.

    PubMed

    Xia, Peng-Fei; Zhang, Guo-Chang; Liu, Jing-Jing; Kwak, Suryang; Tsai, Ching-Sung; Kong, In Iok; Sung, Bong Hyun; Sohn, Jung-Hoon; Wang, Shu-Guang; Jin, Yong-Su

    2016-10-01

    Rapid advances in the capabilities of reading and writing DNA along with increasing understanding of microbial metabolism at the systems-level have paved an incredible path for metabolic engineering. Despite these advances, post-translational tools facilitating functional expression of heterologous enzymes in model hosts have not been developed well. Some bacterial enzymes, such as Escherichia coli xylose isomerase (XI) and arabinose isomerase (AI) which are essential for utilizing cellulosic sugars, cannot be functionally expressed in Saccharomyces cerevisiae. We hypothesized and demonstrated that the mismatching of the HSP60 chaperone systems between bacterial and eukaryotic cells might be the reason these bacterial enzymes cannot be functionally expressed in yeast. The results showed that the co-expression of E. coli GroE can facilitate the functional expression of E. coli XI and AI, as well as the Agrobacterium tumefaciens D-psicose epimerase in S. cerevisiae. The co-expression of bacterial chaperonins in S. cerevisiae is a promising post-translational strategy for the functional expression of bacterial enzymes in yeast. Biotechnol. Bioeng. 2016;113: 2149-2155. © 2016 Wiley Periodicals, Inc. PMID:27003667

  10. Molecular characterization of the group II chaperonin from the hyperthermophilic archaeum Pyrococcus horikoshii OT3.

    PubMed

    Okochi, Mina; Matsuzaki, Hiroki; Nomura, Tomoko; Ishii, Noriyuki; Yohda, Masafumi

    2005-04-01

    The group II chaperonin from the hyperthermophilic archaeum Pyrococcus horikoshii OT3 (PhCPN) and its functional cooperation with the cognate prefoldin were investigated. PhCPN existed as a homo-oligomer in a double-ring structure, which protected the citrate synthase of a porcine heart from thermal aggregation at 45 degrees C, and did the same on the isopropylmalate dehydrogenase (IPMDH) of a thermophilic bacterium, Thermus thermophilus HB8, at 90 degrees C. PhCPN also enhanced the refolding of green fluorescent protein (GFP), which had been unfolded by low pH, in an ATP-dependent manner. Unexpectedly, functional cooperation between PhCPN and Pyrococcus prefoldin (PhPFD) in the refolding of GFP was not observed. Instead, cooperation between PhCPN and PhPFD was observed in the refolding of IPMDH unfolded with guanidine hydrochloride. Although PhCPN alone was not effective in the refolding of IPMDH, the refolding efficiency was enhanced by the cooperation of PhCPN with PhPFD. PMID:15538645

  11. An Unstructured Workshop as a Training Compromise.

    ERIC Educational Resources Information Center

    Moore, R. J.

    1978-01-01

    Because of its poor labor relations and consequent public image, New Zealand's meat industry asked the University of Otago to provide management training. Describes difficulties in developing effective training acceptable to the industry, the compromise workshop approach involving questionnaires and diaries, and the workshop's qualified success.…

  12. 49 CFR 1503.425 - Compromise orders.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 9 2012-10-01 2012-10-01 false Compromise orders. 1503.425 Section 1503.425 Transportation Other Regulations Relating to Transportation (Continued) TRANSPORTATION SECURITY ADMINISTRATION, DEPARTMENT OF HOMELAND SECURITY ADMINISTRATIVE AND PROCEDURAL RULES INVESTIGATIVE AND ENFORCEMENT PROCEDURES Assessment of Civil Penalties...

  13. 49 CFR 1503.425 - Compromise orders.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Compromise orders. 1503.425 Section 1503.425 Transportation Other Regulations Relating to Transportation (Continued) TRANSPORTATION SECURITY ADMINISTRATION, DEPARTMENT OF HOMELAND SECURITY ADMINISTRATIVE AND PROCEDURAL RULES INVESTIGATIVE AND ENFORCEMENT PROCEDURES Assessment of Civil Penalties...

  14. 48 CFR 232.616 - Compromise actions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Compromise actions. 232.616 Section 232.616 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM... actions. Only the department/agency contract financing offices (see 232.070(c)) are authorized...

  15. Political Compromise Makes the World Go 'Round

    ERIC Educational Resources Information Center

    Everett, Diana

    2007-01-01

    Compromise in any context is often hard to accept. It feels like a person is giving up on his or her ideals. This is especially true in dealing with politics. Legislative and congressional bills can be written with the highest of ideals in mind. By the time the bill progresses through committees and the floor debate process, it can look like a…

  16. Disease-Associated Mutations in the HSPD1 Gene Encoding the Large Subunit of the Mitochondrial HSP60/HSP10 Chaperonin Complex

    PubMed Central

    Bross, Peter; Fernandez-Guerra, Paula

    2016-01-01

    Heat shock protein 60 (HSP60) forms together with heat shock protein 10 (HSP10) double-barrel chaperonin complexes that are essential for folding to the native state of proteins in the mitochondrial matrix space. Two extremely rare monogenic disorders have been described that are caused by missense mutations in the HSPD1 gene that encodes the HSP60 subunit of the HSP60/HSP10 chaperonin complex. Investigations of the molecular mechanisms underlying these disorders have revealed that different degrees of reduced HSP60 function produce distinct neurological phenotypes. While mutations with deleterious or strong dominant negative effects are not compatible with life, HSPD1 gene variations found in the human population impair HSP60 function and depending on the mechanism and degree of HSP60 dys- and mal-function cause different phenotypes. We here summarize the knowledge on the effects of disturbances of the function of the HSP60/HSP10 chaperonin complex by disease-associated mutations.

  17. 49 CFR 1018.51 - Reasons for compromising a claim.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... compromise in accordance with the guidelines in 4 CFR 103.4. (b) The Board shall determine the debtor's... compromise in accordance with the Federal Claims Collection Standards, 4 CFR part 103. (c) Compromises... 49 Transportation 8 2010-10-01 2010-10-01 false Reasons for compromising a claim. 1018.51...

  18. 40 CFR 13.25 - Standards for compromise.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Standards for compromise. 13.25 Section 13.25 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GENERAL CLAIMS COLLECTION STANDARDS Compromise of Debts § 13.25 Standards for compromise. (a) EPA may compromise a claim pursuant to this...

  19. 38 CFR 1.931 - Bases for compromise.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Bases for compromise. 1.931 Section 1.931 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS GENERAL PROVISIONS Standards for Compromise of Claims § 1.931 Bases for compromise. (a) VA may compromise a debt if it cannot collect the full amount because:...

  20. Gender Differences in the Readiness To Accept Career Compromise.

    ERIC Educational Resources Information Center

    Gati, Itamar

    Most career decisions involve compromises. The need to compromise can be attributed to the fact that the characteristics of the options in the occupational world do not necessarily match the ideal career image of the career decision maker. This study examined the readiness to compromise and the content of compromise in 1,252 deliberating women and…

  1. 31 CFR 902.5 - Further review of compromise offers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Further review of compromise offers... COMPROMISE OF CLAIMS § 902.5 Further review of compromise offers. If an agency is uncertain whether to accept a firm, written, substantive compromise offer on a debt that is within the agency's...

  2. Folding trajectories of human dihydrofolate reductase inside the GroEL GroES chaperonin cavity and free in solution.

    PubMed

    Horst, Reto; Fenton, Wayne A; Englander, S Walter; Wüthrich, Kurt; Horwich, Arthur L

    2007-12-26

    The chaperonin GroEL binds non-native polypeptides in an open ring via hydrophobic contacts and then, after ATP and GroES binding to the same ring as polypeptide, mediates productive folding in the now hydrophilic, encapsulated cis chamber. The nature of the folding reaction in the cis cavity remains poorly understood. In particular, it is unclear whether polypeptides take the same route to the native state in this cavity as they do when folding spontaneously free in solution. Here, we have addressed this question by using NMR measurements of the time course of acquisition of amide proton exchange protection of human dihydrofolate reductase (DHFR) during folding in the presence of methotrexate and ATP either free in solution or inside the stable cavity formed between a single ring variant of GroEL, SR1, and GroES. Recovery of DHFR refolded by the SR1/GroES-mediated reaction is 2-fold higher than in the spontaneous reaction. Nevertheless, DHFR folding was found to proceed by the same trajectories inside the cis folding chamber and free in solution. These observations are consistent with the description of the chaperonin chamber as an "Anfinsen cage" where polypeptide folding is determined solely by the amino acid sequence, as it is in solution. However, if misfolding occurs in the confinement of the chaperonin cavity, the polypeptide chain cannot undergo aggregation but rather finds its way back to a productive pathway in a manner that cannot be accomplished in solution, resulting in the observed high overall recovery. PMID:18093916

  3. Biochemical Characterization of Mutants in Chaperonin Proteins CCT4 and CCT5 Associated with Hereditary Sensory Neuropathy*

    PubMed Central

    Sergeeva, Oksana A.; Tran, Meme T.; Haase-Pettingell, Cameron; King, Jonathan A.

    2014-01-01

    Hereditary sensory neuropathies are a class of disorders marked by degeneration of the nerve fibers in the sensory periphery neurons. Recently, two mutations were identified in the subunits of the eukaryotic cytosolic chaperonin TRiC, a protein machine responsible for folding actin and tubulin in the cell. C450Y CCT4 was identified in a stock of Sprague-Dawley rats, whereas H147R CCT5 was found in a human Moroccan family. As with many genetically identified mutations associated with neuropathies, the underlying molecular basis of the mutants was not defined. We investigated the biochemical properties of these mutants using an expression system in Escherichia coli that produces homo-oligomeric rings of CCT4 and CCT5. Full-length versions of both mutant protein chains were expressed in E. coli at levels approaching that of the WT chains. Sucrose gradient centrifugation revealed chaperonin-sized complexes of both WT and mutant chaperonins, but with reduced recovery of C450Y CCT4 soluble subunits. Electron microscopy of negatively stained samples of C450Y CCT4 revealed few ring-shaped species, whereas WT CCT4, H147R CCT5, and WT CCT5 revealed similar ring structures. CCT5 complexes were assayed for their ability to suppress aggregation of and refold the model substrate γd-crystallin, suppress aggregation of mutant huntingtin, and refold the physiological substrate β-actin in vitro. H147R CCT5 was not as efficient in chaperoning these substrates as WT CCT5. The subtle effects of these mutations are consistent with the homozygous disease phenotype, in which most functions are carried out during development and adulthood, but some selective function is lost or reduced. PMID:25124038

  4. The composition, structure and stability of a group II chaperonin are temperature regulated in a hyperthermophilic archaeon.

    PubMed

    Kagawa, Hiromi K; Yaoi, Takuro; Brocchieri, Luciano; McMillan, R Andrew; Alton, Thomas; Trent, Jonathan D

    2003-04-01

    The hyperthermoacidophilic archaeon Sulfolobus shibatae contains group II chaperonins, known as rosettasomes, which are two nine-membered rings composed of three different 60 kDa subunits (TF55 alpha, beta and gamma). We sequenced the gene for the gamma subunit and studied the temperature-dependent changes in alpha, beta and gamma expression, their association into rosettasomes and their phylogenetic relationships. Alpha and beta gene expression was increased by heat shock (30 min, 86 degrees C) and decreased by cold shock (30 min, 60 degrees C). Gamma expression was undetectable at heat shock temperatures and low at normal temperatures (75-79 degrees C), but induced by cold shock. Polyacrylamide gel electrophoresis indicated that in vitro alpha and beta subunits form homo-oligomeric rosettasomes, and mixtures of alpha, beta and gamma form hetero-oligomeric rosettasomes. Transmission electron microscopy revealed that beta homo-oligomeric rosettasomes and all hetero-oligomeric rosettasomes associate into filaments. In vivo rosettasomes were hetero-oligomeric with an average subunit ratio of 1alpha:1beta:0.1gamma in cultures grown at 75 degrees C, a ratio of 1alpha:3beta:1gamma in cultures grown at 60 degrees C and a ratio of 2alpha:3beta:0gamma after 86 degrees C heat shock. Using differential scanning calorimetry, we determined denaturation temperatures (Tm) for alpha, beta and gamma subunits of 95.7 degrees C, 96.7 degrees C and 80.5 degrees C, respectively, and observed that rosettasomes containing gamma were relatively less stable than those with alpha and/or beta only. We propose that, in vivo, the rosettasome structure is determined by the relative abundance of subunits and not by a fixed geometry. Furthermore, phylogenetic analyses indicate that archaeal chaperonin subunits underwent multiple duplication events within species (paralogy). The independent evolution of these paralogues raises the possibility that chaperonins have functionally diversified between

  5. BBS10 encodes a vertebrate-specific chaperonin-like protein and is a major BBS locus.

    PubMed

    Stoetzel, Corinne; Laurier, Virginie; Davis, Erica E; Muller, Jean; Rix, Suzanne; Badano, José L; Leitch, Carmen C; Salem, Nabiha; Chouery, Eliane; Corbani, Sandra; Jalk, Nadine; Vicaire, Serge; Sarda, Pierre; Hamel, Christian; Lacombe, Didier; Holder, Muriel; Odent, Sylvie; Holder, Susan; Brooks, Alice S; Elcioglu, Nursel H; Silva, Eduardo D; Da Silva, Eduardo; Rossillion, Béatrice; Sigaudy, Sabine; de Ravel, Thomy J L; Lewis, Richard Alan; Leheup, Bruno; Verloes, Alain; Amati-Bonneau, Patrizia; Mégarbané, André; Poch, Olivier; Bonneau, Dominique; Beales, Philip L; Mandel, Jean-Louis; Katsanis, Nicholas; Dollfus, Hélène

    2006-05-01

    Bardet-Biedl syndrome (BBS) is a genetically heterogeneous ciliopathy. Although nine BBS genes have been cloned, they explain only 40-50% of the total mutational load. Here we report a major new BBS locus, BBS10, that encodes a previously unknown, rapidly evolving vertebrate-specific chaperonin-like protein. We found BBS10 to be mutated in about 20% of an unselected cohort of families of various ethnic origins, including some families with mutations in other BBS genes, consistent with oligogenic inheritance. In zebrafish, mild suppression of bbs10 exacerbated the phenotypes of other bbs morphants. PMID:16582908

  6. Identification, characterization, and expression of the BiP endoplasmic reticulum resident chaperonins in Pneumocystis carinii.

    PubMed Central

    Stedman, T T; Buck, G A

    1996-01-01

    We have isolated, characterized, and examined the expression of the genes encoding BiP endoplasmic reticulum (ER) resident chaperonins responsible for transport, maturation, and proper folding of membrane and secreted proteins from two divergent strains of Pneumocystis carinii. The BiP genes, Pcbip and Prbip, from the P. c. carinii (prototype) strain and the P. c. rattus (variant) strain, respectively, are single-copy genes that reside on chromosomes of approximately 330 and approximately 350 kbp. Both genes encode approximately 72.5-kDa proteins that are most homologous to BiP genes from other organisms and exhibit the amino-terminal signal peptides and carboxyl-terminal ER retention sequences that are hallmarks of BiP proteins. We established short-term P. carinii cultures to examine expression and induction of Pcbip in response to heat shock, glucose starvation, inhibition of protein transport or N-linked glycosylation, and other conditions known to affect proper transport, glycosylation, and maturation of membrane and secreted proteins. These studies indicated that Pcbip mRNA is constitutively expressed but induced under conditions known to induce BiP expression in other organisms. In contrast to mammalian BiP genes but like other fungal BiP genes, P. carinii BiP mRNA levels are induced by heat shock. Finally, the Prbip and Pcbip coding sequences surprisingly exhibit only approximately 83% DNA and approximately 90% amino acid sequence identity and show only limited conservation in noncoding flanking and intron sequences. Analyses of the P. carinii BiP gene sequences support inclusion of P. carinii among the fungi but suggest a large divergence and possible speciation among P. carinii strains infecting a given host. PMID:8890193

  7. A Gradient of ATP Affinities Generates an Asymmetric Power Stroke Driving the Chaperonin TRIC/CCT Folding Cycle

    PubMed Central

    Reissmann, Stefanie; Joachimiak, Lukasz A.; Chen, Bryan; Meyer, Anne S.; Nguyen, Anthony; Frydman, Judith

    2012-01-01

    SUMMARY The eukaryotic chaperonin TRiC/CCT uses ATP cycling to fold many essential proteins that other chaperones cannot fold. This 1 MDa hetero-oligomer consists of two identical stacked rings assembled from eight paralogous subunits, each containing a conserved ATP-binding domain. Here, we report a dramatic asymmetry in the ATP utilization cycle of this ring-shaped chaperonin, despite its apparently symmetric architecture. Only four of the eight different subunits bind ATP at physiological concentrations. ATP binding and hydrolysis by the low-affinity subunits is fully dispensable for TRiC function in vivo. The conserved nucleotide-binding hierarchy among TRiC subunits is evolutionarily modulated through differential nucleoside contacts. Strikingly, high-and low-affinity subunits are spatially segregated within two contiguous hemispheres in the ring, generating an asymmetric power stroke that drives the folding cycle. This unusual mode of ATP utilization likely serves to orchestrate a directional mechanism underlying TRiC/CCT’s unique ability to fold complex eukaryotic proteins. PMID:23041314

  8. Structural Mechanisms of Mutant Huntingtin Aggregation Suppression by the Synthetic Chaperonin-like CCT5 Complex Explained by Cryoelectron Tomography*

    PubMed Central

    Darrow, Michele C.; Sergeeva, Oksana A.; Isas, Jose M.; Galaz-Montoya, Jesús G.; King, Jonathan A.; Langen, Ralf; Schmid, Michael F.; Chiu, Wah

    2015-01-01

    Huntington disease, a neurodegenerative disorder characterized by functional deficits and loss of striatal neurons, is linked to an expanded and unstable CAG trinucleotide repeat in the huntingtin gene (HTT). This DNA sequence translates to a polyglutamine repeat in the protein product, leading to mutant huntingtin (mHTT) protein aggregation. The aggregation of mHTT is inhibited in vitro and in vivo by the TCP-1 ring complex (TRiC) chaperonin. Recently, a novel complex comprised of a single type of TRiC subunit has been reported to inhibit mHTT aggregation. Specifically, the purified CCT5 homo-oligomer complex, when compared with TRiC, has a similar structure, ATP use, and substrate refolding activity, and, importantly, it also inhibits mHTT aggregation. Using an aggregation suppression assay and cryoelectron tomography coupled with a novel computational classification method, we uncover the interactions between the synthetic CCT5 complex (∼1 MDa) and aggregates of mutant huntingtin exon 1 containing 46 glutamines (mHTTQ46-Ex1). We find that, in a similar fashion to TRiC, synthetic CCT5 complex caps mHTT fibrils at their tips and encapsulates mHTT oligomers, providing a structural description of the inhibition of mHTTQ46-Ex1 by CCT5 complex and a shared mechanism of mHTT inhibition between TRiC chaperonin and the CCT5 complex: cap and contain. PMID:25995452

  9. Structural Mechanisms of Mutant Huntingtin Aggregation Suppression by the Synthetic Chaperonin-like CCT5 Complex Explained by Cryoelectron Tomography.

    PubMed

    Darrow, Michele C; Sergeeva, Oksana A; Isas, Jose M; Galaz-Montoya, Jesús G; King, Jonathan A; Langen, Ralf; Schmid, Michael F; Chiu, Wah

    2015-07-10

    Huntington disease, a neurodegenerative disorder characterized by functional deficits and loss of striatal neurons, is linked to an expanded and unstable CAG trinucleotide repeat in the huntingtin gene (HTT). This DNA sequence translates to a polyglutamine repeat in the protein product, leading to mutant huntingtin (mHTT) protein aggregation. The aggregation of mHTT is inhibited in vitro and in vivo by the TCP-1 ring complex (TRiC) chaperonin. Recently, a novel complex comprised of a single type of TRiC subunit has been reported to inhibit mHTT aggregation. Specifically, the purified CCT5 homo-oligomer complex, when compared with TRiC, has a similar structure, ATP use, and substrate refolding activity, and, importantly, it also inhibits mHTT aggregation. Using an aggregation suppression assay and cryoelectron tomography coupled with a novel computational classification method, we uncover the interactions between the synthetic CCT5 complex (∼ 1 MDa) and aggregates of mutant huntingtin exon 1 containing 46 glutamines (mHTTQ46-Ex1). We find that, in a similar fashion to TRiC, synthetic CCT5 complex caps mHTT fibrils at their tips and encapsulates mHTT oligomers, providing a structural description of the inhibition of mHTTQ46-Ex1 by CCT5 complex and a shared mechanism of mHTT inhibition between TRiC chaperonin and the CCT5 complex: cap and contain. PMID:25995452

  10. Regulation and sequence of the Synechococcus sp. strain PCC 7942 groESL operon, encoding a cyanobacterial chaperonin.

    PubMed Central

    Webb, R; Reddy, K J; Sherman, L A

    1990-01-01

    The molecular chaperonins such as GroEL are now widely regarded as essential components for the stabilization of integral membrane or secretory proteins before membrane insertion or translocation, as well as for the assembly of macromolecular complexes such as ribulose bisphosphate carboxylase-oxygenase. The groESL operon of Synechococcus sp. strain PCC 7942 was cloned as two independent lacZ-groEL translational fusions by immunoscreening a lambda ZAP genomic expression library and then sequenced. The derived amino acid sequences of the GroES and GroEL proteins demonstrated very high levels of amino acid identity with cognate chaperonins from bacteria and chloroplasts. The bicistronic 2.4-kilobase transcript from this operon, barely detectable in RNA preparations from cells grown at 30 degrees C, accumulated approximately 120-fold in preparations from cells grown for 20 min at 45 degrees C. Under these conditions, GroEL protein accumulated to 10-fold-higher levels. Primer extension analysis was used to identify a cyanobacterial heat shock promoter located at -81 base pairs from the groES initiation codon. The transcriptional -10 and -35 sequences differ slightly from Escherichia coli consensus heat shock promoter sequences. Images PMID:1975581

  11. Symmetry-free cryo-EM structures of the chaperonin TRiC along its ATPase-driven conformational cycle

    PubMed Central

    Cong, Yao; Schröder, Gunnar F; Meyer, Anne S; Jakana, Joanita; Ma, Boxue; Dougherty, Matthew T; Schmid, Michael F; Reissmann, Stefanie; Levitt, Michael; Ludtke, Steven L; Frydman, Judith; Chiu, Wah

    2012-01-01

    The eukaryotic group II chaperonin TRiC/CCT is a 16-subunit complex with eight distinct but similar subunits arranged in two stacked rings. Substrate folding inside the central chamber is triggered by ATP hydrolysis. We present five cryo-EM structures of TRiC in apo and nucleotide-induced states without imposing symmetry during the 3D reconstruction. These structures reveal the intra- and inter-ring subunit interaction pattern changes during the ATPase cycle. In the apo state, the subunit arrangement in each ring is highly asymmetric, whereas all nucleotide-containing states tend to be more symmetrical. We identify and structurally characterize an one-ring closed intermediate induced by ATP hydrolysis wherein the closed TRiC ring exhibits an observable chamber expansion. This likely represents the physiological substrate folding state. Our structural results suggest mechanisms for inter-ring-negative cooperativity, intra-ring-positive cooperativity, and protein-folding chamber closure of TRiC. Intriguingly, these mechanisms are different from other group I and II chaperonins despite their similar architecture. PMID:22045336

  12. Chaperonin 20 might be an iron chaperone for superoxide dismutase in activating iron superoxide dismutase (FeSOD)

    PubMed Central

    Kuo, Wen-Yu; Huang, Chien-Hsun; Jinn, Tsung-Luo

    2013-01-01

    Activation of Cu/Zn superoxide dismutases (CuZnSODs) is aided by Cu incorporation and disulfide isomerization by Cu chaperone of SOD (CCS). As well, an Fe-S cluster scaffold protein, ISU, might alter the incorporation of Fe or Mn into yeast MnSOD (ySOD2), thus leading to active or inactive ySOD2. However, metallochaperones involved in the activation of FeSODs are unknown. Recently, we found that a chloroplastic chaperonin cofactor, CPN20, could mediate FeSOD activity. To investigate whether Fe incorporation in FeSOD is affected by CPN20, we used inductively coupled plasma mass spectrometry to analyze the ability of CPN20 to bind Fe. CPN20 could bind Fe, and the Fe binding to FeSOD was increased with CPN20 incubation. Thus, CPN20 might be an Fe chaperone for FeSOD activation, a role independent of its well-known co-chaperonin activity. PMID:23299425

  13. In vitro stabilization and in vivo solubilization of foreign proteins by the beta subunit of a chaperonin from the hyperthermophilic archaeon Pyrococcus sp. strain KOD1.

    PubMed Central

    Yan, Z; Fujiwara, S; Kohda, K; Takagi, M; Imanaka, T

    1997-01-01

    The gene encoding the beta subunit of a molecular chaperonin from the hyperthermophilic archaeon Pyrococcus sp. strain KOD1 (cpkB) was cloned, sequenced, and expressed in Escherichia coli. The cpkB gene is composed of 1,641 nucleotides, encoding a protein (546 amino acids) with a molecular mass of 59,140 Da. The enhancing effect of CpkB on enzyme stability was examined by using Saccharomyces cerevisiae alcohol dehydrogenase (ADH). Purified recombinant CpkB prevents thermal denaturation and enhances thermostability of ADH. CpkB requires ATP for its chaperonin function at a low CpkB concentration; however, CpkB functions without ATP when present in excess. In vivo chaperonin function for the solubilization of insoluble proteins was also studied by coexpressing CpkB and CobQ (cobryic acid synthase), indicating that CpkB is useful for solubilizing the insoluble proteins in vivo. These results suggest that the beta subunit plays a major role in chaperonin activity and is functional without the alpha subunit. PMID:9023959

  14. Differential conformational modulations of MreB folding upon interactions with GroEL/ES and TRiC chaperonin components

    PubMed Central

    Moparthi, Satish Babu; Carlsson, Uno; Vincentelli, Renaud; Jonsson, Bengt-Harald; Hammarström, Per; Wenger, Jérôme

    2016-01-01

    Here, we study and compare the mechanisms of action of the GroEL/GroES and the TRiC chaperonin systems on MreB client protein variants extracted from E. coli. MreB is a homologue to actin in prokaryotes. Single-molecule fluorescence correlation spectroscopy (FCS) and time-resolved fluorescence polarization anisotropy report the binding interaction of folding MreB with GroEL, GroES and TRiC. Fluorescence resonance energy transfer (FRET) measurements on MreB variants quantified molecular distance changes occurring during conformational rearrangements within folding MreB bound to chaperonins. We observed that the MreB structure is rearranged by a binding-induced expansion mechanism in TRiC, GroEL and GroES. These results are quantitatively comparable to the structural rearrangements found during the interaction of β-actin with GroEL and TRiC, indicating that the mechanism of chaperonins is conserved during evolution. The chaperonin-bound MreB is also significantly compacted after addition of AMP-PNP for both the GroEL/ES and TRiC systems. Most importantly, our results showed that GroES may act as an unfoldase by inducing a dramatic initial expansion of MreB (even more than for GroEL) implicating a role for MreB folding, allowing us to suggest a delivery mechanism for GroES to GroEL in prokaryotes. PMID:27328749

  15. The Cpn10(1) co-chaperonin of A. thaliana functions only as a hetero-oligomer with Cpn20.

    PubMed

    Vitlin Gruber, Anna; Zizelski, Gal; Azem, Abdussalam; Weiss, Celeste

    2014-01-01

    The A. thaliana genome encodes five co-chaperonin homologs, three of which are destined to the chloroplast. Two of the proteins, Cpn10(2) and Cpn20, form functional homo-oligomers in vitro. In the current work, we present data on the structure and function of the third A. thaliana co-chaperonin, which exhibits unique properties. We found that purified recombinant Cpn10(1) forms inactive dimers in solution, in contrast to the active heptamers that are formed by canonical Cpn10s. Additionally, our data demonstrate that Cpn10(1) is capable of assembling into active hetero-oligomers together with Cpn20. This finding was reinforced by the formation of active co-chaperonin species upon mixing an inactive Cpn20 mutant with the inactive Cpn10(1). The present study constitutes the first report of a higher plant Cpn10 subunit that is able to function only upon formation of hetero-oligomers with other co-chaperonins. PMID:25419702

  16. The Cpn10(1) Co-Chaperonin of A. thaliana Functions Only as a Hetero-Oligomer with Cpn20

    PubMed Central

    Vitlin Gruber, Anna; Zizelski, Gal; Azem, Abdussalam; Weiss, Celeste

    2014-01-01

    The A. thaliana genome encodes five co-chaperonin homologs, three of which are destined to the chloroplast. Two of the proteins, Cpn10(2) and Cpn20, form functional homo-oligomers in vitro. In the current work, we present data on the structure and function of the third A. thaliana co-chaperonin, which exhibits unique properties. We found that purified recombinant Cpn10(1) forms inactive dimers in solution, in contrast to the active heptamers that are formed by canonical Cpn10s. Additionally, our data demonstrate that Cpn10(1) is capable of assembling into active hetero-oligomers together with Cpn20. This finding was reinforced by the formation of active co-chaperonin species upon mixing an inactive Cpn20 mutant with the inactive Cpn10(1). The present study constitutes the first report of a higher plant Cpn10 subunit that is able to function only upon formation of hetero-oligomers with other co-chaperonins. PMID:25419702

  17. Trichobezoar Causing Airway Compromise during Esophagogastroduodenoscopy.

    PubMed

    Kao, Erica Y; Scalzitti, Nicholas J; Dion, Gregory R; Bowe, Sarah N

    2015-01-01

    Objectives. (1) Report the case of a 5-year-old female with trichotillomania and trichophagia that suffered airway compromise during esophagogastroduodenoscopy for removal of a trichobezoar. (2) Provide management recommendations for an unusual foreign body causing extubation and partial airway obstruction. Methods. Case report of a rare situation of airway compromise caused by a trichobezoar. Results. A 5-year-old patient underwent endoscopic retrieval of a gastric trichobezoar (hairball) by the gastroenterology service under general endotracheal anesthesia in a sedation unit. During removal, the hairball, due to its large size, dislodged the endotracheal tube, effectively extubating the patient. The bezoar became lodged at the cricopharyngeus muscle. Attempts to remove the bezoar or reintubation were unsuccessful. The child was able to be mask ventilated while the otolaryngology service was called. Direct laryngoscopy revealed a hairball partially obstructing the view of the glottis from its position in the postcricoid area. The hairball, still entrapped in the snare from the esophagoscope, was grasped with Magill forceps and slowly extracted. The patient was then reintubated and the airway and esophagus were reevaluated. Conclusions. Trichobezoar is an uncommon cause of airway foreign body. Careful attention to airway management during these and similar foreign body extractions can prevent inadvertent extubations. PMID:26457086

  18. Trichobezoar Causing Airway Compromise during Esophagogastroduodenoscopy

    PubMed Central

    Kao, Erica Y.; Scalzitti, Nicholas J.; Dion, Gregory R.; Bowe, Sarah N.

    2015-01-01

    Objectives. (1) Report the case of a 5-year-old female with trichotillomania and trichophagia that suffered airway compromise during esophagogastroduodenoscopy for removal of a trichobezoar. (2) Provide management recommendations for an unusual foreign body causing extubation and partial airway obstruction. Methods. Case report of a rare situation of airway compromise caused by a trichobezoar. Results. A 5-year-old patient underwent endoscopic retrieval of a gastric trichobezoar (hairball) by the gastroenterology service under general endotracheal anesthesia in a sedation unit. During removal, the hairball, due to its large size, dislodged the endotracheal tube, effectively extubating the patient. The bezoar became lodged at the cricopharyngeus muscle. Attempts to remove the bezoar or reintubation were unsuccessful. The child was able to be mask ventilated while the otolaryngology service was called. Direct laryngoscopy revealed a hairball partially obstructing the view of the glottis from its position in the postcricoid area. The hairball, still entrapped in the snare from the esophagoscope, was grasped with Magill forceps and slowly extracted. The patient was then reintubated and the airway and esophagus were reevaluated. Conclusions. Trichobezoar is an uncommon cause of airway foreign body. Careful attention to airway management during these and similar foreign body extractions can prevent inadvertent extubations. PMID:26457086

  19. Identifying genetic relatives without compromising privacy

    PubMed Central

    He, Dan; Furlotte, Nicholas A.; Hormozdiari, Farhad; Joo, Jong Wha J.; Wadia, Akshay; Ostrovsky, Rafail; Sahai, Amit; Eskin, Eleazar

    2014-01-01

    The development of high-throughput genomic technologies has impacted many areas of genetic research. While many applications of these technologies focus on the discovery of genes involved in disease from population samples, applications of genomic technologies to an individual’s genome or personal genomics have recently gained much interest. One such application is the identification of relatives from genetic data. In this application, genetic information from a set of individuals is collected in a database, and each pair of individuals is compared in order to identify genetic relatives. An inherent issue that arises in the identification of relatives is privacy. In this article, we propose a method for identifying genetic relatives without compromising privacy by taking advantage of novel cryptographic techniques customized for secure and private comparison of genetic information. We demonstrate the utility of these techniques by allowing a pair of individuals to discover whether or not they are related without compromising their genetic information or revealing it to a third party. The idea is that individuals only share enough special-purpose cryptographically protected information with each other to identify whether or not they are relatives, but not enough to expose any information about their genomes. We show in HapMap and 1000 Genomes data that our method can recover first- and second-order genetic relationships and, through simulations, show that our method can identify relationships as distant as third cousins while preserving privacy. PMID:24614977

  20. Chaperonins induce an amyloid-like transformation of ovine prion protein: the fundamental difference in action between eukaryotic TRiC and bacterial GroEL.

    PubMed

    Kiselev, Georgy G; Naletova, Irina N; Sheval, Evgeny V; Stroylova, Yulia Y; Schmalhausen, Elena V; Haertlé, Thomas; Muronetz, Vladimir I

    2011-12-01

    Molecular chaperones have been shown to be involved in the processes taking place during the pathogenesis of various amyloid neurodegenerative diseases. However, contradictory literature reports suggest that different molecular chaperones can either stimulate or prevent the formation of amyloid structures from distinct amyloidogenic proteins. In the present work, we concentrated on the effects caused by two molecular chaperonins, ovine TRiC and bacterial GroEL, on the aggregation and conformational state of ovine PrP. Both chaperonins were shown to bind native PrP and to produce amyloid-like forms of ovine PrP enriched with beta-structures but, while GroEL acted in an ATP-dependent manner, TRiC was shown to cause the same effect only in the absence of Mg-ATP (i.e. in the inactive form). In the presence of chaperonin GroEL, ovine PrP was shown to form micellar particles, approximately 100-200nm in diameter, which were observed both by dynamic light scattering assay and by electron microscopy. The content of these particles was significantly higher in the presence of Mg-ATP and, only under these conditions, GroEL produced amyloid-like species enriched with beta-structures. TRiC was shown to induce the formation of amyloid fibrils observed by electron microscopy, but only in the absence of Mg-ATP. This study suggests the important role of the cytosolic chaperonin TRiC in the propagation of amyloid structures in vivo during the development of amyloid diseases and the possible role of the bacterial chaperonin GroEL, located in the intestinal microflora, in the induction of these diseases. PMID:21856455

  1. Mitochondrial Hsp60 Chaperonopathy Causes an Autosomal-Recessive Neurodegenerative Disorder Linked to Brain Hypomyelination and Leukodystrophy

    PubMed Central

    Magen, Daniella; Georgopoulos, Costa; Bross, Peter; Ang, Debbie; Segev, Yardena; Goldsher, Dorit; Nemirovski, Alexandra; Shahar, Eli; Ravid, Sarit; Luder, Anthony; Heno, Bayan; Gershoni-Baruch, Ruth; Skorecki, Karl; Mandel, Hanna

    2008-01-01

    Hypomyelinating leukodystrophies (HMLs) are disorders involving aberrant myelin formation. The prototype of primary HMLs is the X-linked Pelizaeus-Merzbacher disease (PMD) caused by mutations in PLP1. Recently, homozygous mutations in GJA12 encoding connexin 47 were found in patients with autosomal-recessive Pelizaeus-Merzbacher-like disease (PMLD). However, many patients of both genders with PMLD carry neither PLP1 nor GJA12 mutations. We report a consanguineous Israeli Bedouin kindred with clinical and radiological findings compatible with PMLD, in which linkage to PLP1 and GJA12 was excluded. Using homozygosity mapping and mutation analysis, we have identified a homozygous missense mutation (D29G) not previously described in HSPD1, encoding the mitochondrial heat-shock protein 60 (Hsp60) in all affected individuals. The D29G mutation completely segregates with the disease-associated phenotype. The pathogenic effect of D29G on Hsp60-chaperonin activity was verified by an in vivo E. coli complementation assay, which demonstrated compromised ability of the D29G-Hsp60 mutant protein to support E. coli survival, especially at high temperatures. The disorder, which we have termed MitCHAP-60 disease, can be distinguished from spastic paraplegia 13 (SPG13), another Hsp60-associated autosomal-dominant neurodegenerative disorder, by its autosomal-recessive inheritance pattern, as well as by its early-onset, profound cerebral involvement and lethality. Our findings suggest that Hsp60 defects can cause neurodegenerative pathologies of varying severity, not previously suspected on the basis of the SPG13 phenotype. These findings should help to clarify the important role of Hsp60 in myelinogenesis and neurodegeneration. PMID:18571143

  2. Overexpression of chaperonin containing TCP1, subunit 3 predicts poor prognosis in hepatocellular carcinoma

    PubMed Central

    Cui, Xiao; Hu, Zhi-Ping; Li, Zhao; Gao, Peng-Ji; Zhu, Ji-Ye

    2015-01-01

    AIM: To investigate the value of chaperonin containing TCP1, subunit 3 (CCT3) to predict the prognosis of patients with hepatocellular carcinoma (HCC) and determine its function in HCC progression. METHODS: CCT3 expression levels were examined in human non-cancerous liver tissues and a variety of HCC cell lines by quantitative real-time PCR and immunoblotting. CCT3 expression was suppressed by small interfering RNA. The effects of reducing CCT3 expression in HCC cells were tested. The 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide (MTT) assay, cell counting experiment, cell cycle assay, apoptosis assay and invasion assay were employed to evaluate cell functions in vitro. Immunohistochemistry was performed on HCC specimens. In addition, CCT3 expression in HCC specimens was also assessed at the protein and mRNA level. Associations between clinicopathological characteristics and prognosis were analyzed, along with the possible mechanisms involved in CCT3’s function in HCC progression. RESULTS: The expression levels of CCT3 mRNA and protein were upregulated in HCC cell lines in contrast to adjacent non-cancerous tissues. Reducing CCT3 expression not only suppressed cell proliferation in cell counts, MTT assay, cell cycle assay and induced cell apoptosis (P < 0.05 vs negative control), but also inhibited the tumor cell invasion capacity in vitro (P < 0.01 vs negative control). Overexpression of CCT3 in the nuclei of cancer cells in HCC specimens (58 of 104 patients, 55.8%) was associated with poor prognosis in HCC patients (3-year survival rate, 55.5% vs 84.2%, P = 0.020) after hepatectomy. Mechanistic analyses showed that signal transducer and activator of transcription 3 (STAT3) activation was decreased even when stimulated by interleukin-6 after knocking down CCT3 in the HepG2 cell line. CONCLUSION: Overexpression of CCT3 in the nuclei of cancerous cells is associated with HCC progression. CCT3 may be a target that affects the activation of STAT3 in

  3. Chaperonin-Based Biolayer Interferometry To Assess the Kinetic Stability of Metastable, Aggregation-Prone Proteins.

    PubMed

    Lea, Wendy A; O'Neil, Pierce T; Machen, Alexandra J; Naik, Subhashchandra; Chaudhri, Tapan; McGinn-Straub, Wesley; Tischer, Alexander; Auton, Matthew T; Burns, Joshua R; Baldwin, Michael R; Khar, Karen R; Karanicolas, John; Fisher, Mark T

    2016-09-01

    Stabilizing the folded state of metastable and/or aggregation-prone proteins through exogenous ligand binding is an appealing strategy for decreasing disease pathologies caused by protein folding defects or deleterious kinetic transitions. Current methods of examining binding of a ligand to these marginally stable native states are limited because protein aggregation typically interferes with analysis. Here, we describe a rapid method for assessing the kinetic stability of folded proteins and monitoring the effects of ligand stabilization for both intrinsically stable proteins (monomers, oligomers, and multidomain proteins) and metastable proteins (e.g., low Tm) that uses a new GroEL chaperonin-based biolayer interferometry (BLI) denaturant pulse platform. A kinetically controlled denaturation isotherm is generated by exposing a target protein, immobilized on a BLI biosensor, to increasing denaturant concentrations (urea or GuHCl) in a pulsatile manner to induce partial or complete unfolding of the attached protein population. Following the rapid removal of the denaturant, the extent of hydrophobic unfolded/partially folded species that remains is detected by an increased level of GroEL binding. Because this kinetic denaturant pulse is brief, the amplitude of binding of GroEL to the immobilized protein depends on the duration of the exposure to the denaturant, the concentration of the denaturant, wash times, and the underlying protein unfolding-refolding kinetics; fixing all other parameters and plotting the GroEL binding amplitude versus denaturant pulse concentration result in a kinetically controlled denaturation isotherm. When folding osmolytes or stabilizing ligands are added to the immobilized target proteins before and during the denaturant pulse, the diminished population of unfolded/partially folded protein manifests as a decreased level of GroEL binding and/or a marked shift in these kinetically controlled denaturation profiles to higher denaturant

  4. 49 CFR 89.13 - Documentary evidence of compromise.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Documentary evidence of compromise. 89.13 Section 89.13 Transportation Office of the Secretary of Transportation IMPLEMENTATION OF THE FEDERAL CLAIMS COLLECTION ACT General § 89.13 Documentary evidence of compromise. A compromise of any claim is not final...

  5. 49 CFR 89.13 - Documentary evidence of compromise.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 1 2011-10-01 2011-10-01 false Documentary evidence of compromise. 89.13 Section 89.13 Transportation Office of the Secretary of Transportation IMPLEMENTATION OF THE FEDERAL CLAIMS COLLECTION ACT General § 89.13 Documentary evidence of compromise. A compromise of any claim is not final...

  6. 26 CFR 300.3 - Offer to compromise fee.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Offer to compromise fee. 300.3 Section 300.3... ADMINISTRATION USER FEES § 300.3 Offer to compromise fee. (a) Applicability. This section applies to the... provided in this section, this fee applies to all offers to compromise accepted for processing. (b) Fee....

  7. 20 CFR 340.13 - Compromise of amounts recoverable.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... INSURANCE ACT RECOVERY OF BENEFITS § 340.13 Compromise of amounts recoverable. The Board or its designee may compromise an amount recoverable, provided such amount does not exceed $100,000, excluding interest, or such... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Compromise of amounts recoverable....

  8. 31 CFR 902.2 - Bases for compromise.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Bases for compromise. 902.2 Section 902.2 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FEDERAL CLAIMS COLLECTION STANDARDS (DEPARTMENT OF THE TREASURY-DEPARTMENT OF JUSTICE) STANDARDS FOR THE COMPROMISE OF CLAIMS § 902.2 Bases for compromise....

  9. 49 CFR 89.13 - Documentary evidence of compromise.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 1 2013-10-01 2013-10-01 false Documentary evidence of compromise. 89.13 Section 89.13 Transportation Office of the Secretary of Transportation IMPLEMENTATION OF THE FEDERAL CLAIMS COLLECTION ACT General § 89.13 Documentary evidence of compromise. A compromise of any claim is not final...

  10. 49 CFR 89.13 - Documentary evidence of compromise.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 false Documentary evidence of compromise. 89.13 Section 89.13 Transportation Office of the Secretary of Transportation IMPLEMENTATION OF THE FEDERAL CLAIMS COLLECTION ACT General § 89.13 Documentary evidence of compromise. A compromise of any claim is not final...

  11. 49 CFR 89.13 - Documentary evidence of compromise.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 1 2014-10-01 2014-10-01 false Documentary evidence of compromise. 89.13 Section 89.13 Transportation Office of the Secretary of Transportation IMPLEMENTATION OF THE FEDERAL CLAIMS COLLECTION ACT General § 89.13 Documentary evidence of compromise. A compromise of any claim is not final...

  12. 5 CFR 185.146 - Compromise or settlement.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Compromise or settlement. 185.146 Section 185.146 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PROGRAM FRAUD CIVIL REMEDIES § 185.146 Compromise or settlement. (a) Parties may make offers of compromise...

  13. 49 CFR 1018.71 - Referral of a compromise offer.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 8 2010-10-01 2010-10-01 false Referral of a compromise offer. 1018.71 Section... § 1018.71 Referral of a compromise offer. The Board may refer a debtor's firm written offer of compromise which is substantial in amount to GAO or to DOJ if the Board is uncertain whether the offer should...

  14. 27 CFR 70.436 - Offers in compromise.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Offers in compromise. 70.436 Section 70.436 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... Cigarette Papers and Tubes § 70.436 Offers in compromise. Procedure in the case of offers in compromise...

  15. 27 CFR 70.415 - Offers in compromise.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Offers in compromise. 70.415 Section 70.415 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... Beer § 70.415 Offers in compromise. Procedure in the case of offers in compromise of liabilities...

  16. Institutional Commitments, Individual Compromises: Identity-Related Responses to Compromise in an Australian University

    ERIC Educational Resources Information Center

    Churchman, Deborah

    2006-01-01

    This study explores compromises by individual academic staff, which reflect their multiple understandings of academic work. I offer a brief overview of the changing Australian tertiary sector environment and the ways in which this has had an impact on the academic role. The discussion centres around the need for investigations of academia to be…

  17. Morgellons: contested illness, diagnostic compromise and medicalisation.

    PubMed

    Fair, Brian

    2010-05-01

    The case of Morgellons illustrates how the emergence of a new medically contested illness intersected with and impacted on the diagnostic processes of an existing uncontested psychiatric condition, Delusional Parasitosis (DP). More specifically, the sociopolitical processes at play in the contested illness, Morgellons, dubiously reflect patient empowerment, as well the resilience and power of medical jurisdiction. This research offers insights into the contested illness and medicalisation literatures, and aims to bridge these two approaches towards the relationship between patient empowerment and medical authority, which I do through the notion of doctor-patient compromise. The data for this research come from a comprehensive qualitative analysis of Morgellons discourse through four key sources: the pro-Morgellons website Morgellons.org; the anti-Morgellons website Morgellonswatch.com; the popular media's portrayal of Morgellons; and the DP and Morgellons articles published in peer-reviewed medical journals, as made available on PubMed. PMID:20149149

  18. Purification and characterization of chaperonin 60 and heat-shock protein 70 from chromoplasts of Narcissus pseudonarcissus.

    PubMed Central

    Bonk, M; Tadros, M; Vandekerckhove, J; Al-Babili, S; Beyer, P

    1996-01-01

    In chromoplast differentiation during flower formation in Narcissus pseudonarcissus, the molecular chaperones chaperonin 60 (Cpn60; alpha and beta) and heat-shock protein 70 (Hsp70) greatly increase in abundance. Both were purified and shown to be present in a functional form in chromoplasts, indicating their requirement in the extensive structural rearrangements during the chloroplast-to-chromoplast transition. The purified proteins, sequenced N terminally and from internal peptides, showed strong homology to plastid Cpn60 and Hsp 70 representatives from other plant species. During chromoplast differentiation, the carotenoid biosynthetic pathway is strongly induced. The corresponding enzymes are all nuclear encoded and form a large, soluble, hetero-oligomeric protein complex after import but prior to their membrane attachment. By immunoprecipitations we have shown that the plastid Hsp70 is a structural constituent of a soluble entity also containing phytoene desaturase. PMID:8754688

  19. Folding of newly translated membrane protein CCR5 is assisted by the chaperonin GroEL-GroES

    NASA Astrophysics Data System (ADS)

    Chi, Haixia; Wang, Xiaoqiang; Li, Jiqiang; Ren, Hao; Huang, Fang

    2015-11-01

    The in vitro folding of newly translated human CC chemokine receptor type 5 (CCR5), which belongs to the physiologically important family of G protein-coupled receptors (GPCRs), has been studied in a cell-free system supplemented with the surfactant Brij-35. The freshly synthesized CCR5 can spontaneously fold into its biologically active state but only slowly and inefficiently. However, on addition of the GroEL-GroES molecular chaperone system, the folding of the nascent CCR5 was significantly enhanced, as was the structural stability and functional expression of the soluble form of CCR5. The chaperonin GroEL was partially effective on its own, but for maximum efficiency both the GroEL and its GroES lid were necessary. These results are direct evidence for chaperone-assisted membrane protein folding and therefore demonstrate that GroEL-GroES may be implicated in the folding of membrane proteins.

  20. Folding of newly translated membrane protein CCR5 is assisted by the chaperonin GroEL-GroES

    PubMed Central

    Chi, Haixia; Wang, Xiaoqiang; Li, Jiqiang; Ren, Hao; Huang, Fang

    2015-01-01

    The in vitro folding of newly translated human CC chemokine receptor type 5 (CCR5), which belongs to the physiologically important family of G protein-coupled receptors (GPCRs), has been studied in a cell-free system supplemented with the surfactant Brij-35. The freshly synthesized CCR5 can spontaneously fold into its biologically active state but only slowly and inefficiently. However, on addition of the GroEL-GroES molecular chaperone system, the folding of the nascent CCR5 was significantly enhanced, as was the structural stability and functional expression of the soluble form of CCR5. The chaperonin GroEL was partially effective on its own, but for maximum efficiency both the GroEL and its GroES lid were necessary. These results are direct evidence for chaperone-assisted membrane protein folding and therefore demonstrate that GroEL-GroES may be implicated in the folding of membrane proteins. PMID:26585937

  1. Functional characterization of the α- and β-subunits of a group II chaperonin from Aeropyrum pernix K1.

    PubMed

    Lee, Jin-Woo; Kim, Se Won; Kim, Jeong-Hwan; Jeon, Sung-Jong; Kwon, Hyun-Ju; Kim, Byung-Woo; Nam, Soo-Wan

    2013-06-28

    We isolated and functionally characterized the α- and β- subunits (ApCpnA and ApCpnB) of a chaperonin from Aeropyrum pernix K1. The constructed vectors pET3d- ApCpnA and pET21a-ApCpnB were transformed into E. coli Rosetta (DE3), BL21 (DE3), or CodonPlus (DE3) cells. The expression of ApCpnA (60.7 kDa) and ApCpnB (61.2 kDa) was confirmed by SDS-PAGE analysis. Recombinant ApCpnA and ApCpnB were purified by heat-shock treatment and anion-exchange chromatography. ApCpnA and ApCpnB were able to hydrolyze not only ATP, but also CTP, GTP, and UTP, albeit with different efficacies. Purified ApCpnA and ApCpnB showed the highest ATPase, CTPase, UTPase, and GTPase activities at 80°C. Furthermore, the addition of ApCpnA and ApCpnB effectively protected citrate synthase (CS) and alcohol dehydrogenase (ADH) from thermal aggregation and inactivation at 43°C and 50°C, respectively. In particular, the addition of ATP or CTP to ApCpnA and ApCpnB resulted in the most effective prevention of thermal aggregation and inactivation of CS and ADH. The ATPase activity of the two chaperonin subunits was dependent on the salt concentration. Among the ions we examined, potassium ions were the most effective at enhancing the ATP hydrolysis activity of ApCpnA and ApCpnB. PMID:23676910

  2. Female genital alteration: a compromise solution.

    PubMed

    Arora, Kavita Shah; Jacobs, Allan J

    2016-03-01

    Despite 30 years of advocacy, the prevalence of non-therapeutic female genital alteration (FGA) in minors is stable in many countries. Educational efforts have minimally changed the prevalence of this procedure in regions where it has been widely practiced. In order to better protect female children from the serious and long-term harms of some types of non-therapeutic FGA, we must adopt a more nuanced position that acknowledges a wide spectrum of procedures that alter female genitalia. We offer a revised categorisation for non-therapeutic FGA that groups procedures by effect and not by process. Acceptance of de minimis procedures that generally do not carry long-term medical risks is culturally sensitive, does not discriminate on the basis of gender, and does not violate human rights. More morbid procedures should not be performed. However, accepting de minimis non-therapeutic f FGA procedures enhances the effort of compassionate practitioners searching for a compromise position that respects cultural differences but protects the health of their patients. PMID:26902479

  3. Location and Flexibility of the Unique C-Terminal Tail of Aquifex aeolicus Co-Chaperonin Protein 10 as Derived by Cryo-Electron Microscopy and Biophysical Techniques

    PubMed Central

    Chen, Dong-Hua; Luke, Kathryn; Zhang, Junjie; Chiu, Wah; Wittung-Stafshede, Pernilla

    2008-01-01

    Co-chaperonin protein 10 (cpn10, GroES in Escherichia coli) is a ring-shaped heptameric protein that facilitates substrate folding when in complex with cpn60 (GroEL in E. coli). The cpn10 from the hyperthermophilic, ancient bacterium Aquifex aeolicus (Aacpn10) has a 25-residue C-terminal extension in each monomer not found in any other cpn10 protein. Earlier in vitro work has shown that this tail is not needed for heptamer assembly or protein function. Without the tail, however, the heptamers (Aacpn10del-25) readily aggregate into fibrillar stacked rings. To explain this phenomenon, we performed binding experiments with a peptide construct of the tail to establish its specificity for Aacpn10del-25 and used cryo-electron microscopy to determine the three-dimensional (3D) structure of the GroEL–Aacpn10–ADP complex at an 8-Å resolution. We found that the GroEL–Aacpn10 structure is similar to the GroEL–GroES structure at this resolution, suggesting that Aacpn10 has molecular interactions with cpn60 similar to other cpn10s. The cryo-electron microscopy density map does not directly reveal the density of the Aacpn10 25-residue tail. However, the 3D statistical variance coefficient map computed from multiple 3D reconstructions with randomly selected particle images suggests that the tail is located at the Aacpn10 monomer–monomer interface and extends toward the cis-ring apical domain of GroEL. The tail at this location does not block the formation of a functional co-chaperonin/chaperonin complex but limits self-aggregation into linear fibrils at high temperatures. In addition, the 3D variance coefficient map identifies several regions inside the GroEL–Aacpn10 complex that have flexible conformations. This observation is in full agreement with the structural properties of an effective chaperonin. PMID:18588898

  4. Isolation and Characterization of a Second Subunit of Molecular Chaperonin from Pyrococcus kodakaraensis KOD1: Analysis of an ATPase-Deficient Mutant Enzyme

    PubMed Central

    Izumi, Michi; Fujiwara, Shinsuke; Takagi, Masahiro; Kanaya, Shigenori; Imanaka, Tadayuki

    1999-01-01

    The cpkA gene encoding a second (α) subunit of archaeal chaperonin from Pyrococcus kodakaraensis KOD1 was cloned, sequenced, and expressed in Escherichia coli. Recombinant CpkA was studied for chaperonin functions in comparison with CpkB (β subunit). The effect on decreasing the insoluble form of proteins was examined by coexpressing CpkA or CpkB with CobQ (cobyric acid synthase from P. kodakaraensis) in E. coli. The results indicate that both CpkA and CpkB effectively decrease the amount of the insoluble form of CobQ. Both CpkA and CpkB possessed the same ATPase activity as other bacterial and eukaryal chaperonins. The ATPase-deficient mutant proteins CpkA-D95K and CpkB-D95K were constructed by changing conserved Asp95 to Lys. Effect of the mutation on the ATPase activity and CobQ solubilization was examined. Neither mutant exhibited ATPase activity in vitro. Nevertheless, they decreased the amount of the insoluble form of CobQ by coexpression as did wild-type CpkA and CpkB. These results implied that both CpkA and CpkB could assist protein folding for nascent protein in E. coli without requiring energy from ATP hydrolysis. PMID:10103287

  5. Contribution of the C-terminal region to the thermostability of the archaeal group II chaperonin from Thermococcus sp. strain KS-1.

    PubMed

    Yoshida, Takao; Kanzaki, Taro; Iizuka, Ryo; Komada, Toshihiro; Zako, Tamotsu; Suzuki, Rintaro; Maruyama, Tadashi; Yohda, Masafumi

    2006-10-01

    Chaperonin is a double ring-shaped oligomeric protein complex, which captures a protein in the folding intermediate state and assists its folding in an ATP-dependent manner. The chaperonin from a hyperthermophilic archaeum, Thermococcus sp. strain KS-1, is a group II chaperonin and is composed of two distinct subunits, alpha and beta. Although these subunits are highly homologous in sequence, the homo-oligomer of the beta-subunit is more thermostable than that of the alpha-subunit. To identify the region responsible for this difference in thermostability, we constructed domain-exchange mutants. The mutants containing the equatorial domain of the beta-subunit were more resistant to thermal dissociation than the mutants with that of the alpha-subunit. Thermostability of a beta-subunit mutant whose C-terminal 22 residues were replaced with those of the alpha-subunit decreased to the comparable level of that of the alpha-subunit homo-oligomer. These results indicate that the difference in thermostability between alpha- and beta-subunits mainly originates in the C-terminal residues in the equatorial domain, only where they exhibit substantial sequence difference. PMID:16685467

  6. 10 CFR 429.132 - Compromise and settlement.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Compromise and settlement. 429.132 Section 429.132 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR CONSUMER PRODUCTS AND COMMERCIAL AND INDUSTRIAL EQUIPMENT Enforcement § 429.132 Compromise and settlement. (a) DOE may...

  7. 10 CFR 429.132 - Compromise and settlement.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Compromise and settlement. 429.132 Section 429.132 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR CONSUMER PRODUCTS AND COMMERCIAL AND INDUSTRIAL EQUIPMENT Enforcement § 429.132 Compromise and settlement. (a) DOE may...

  8. 10 CFR 429.132 - Compromise and settlement.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Compromise and settlement. 429.132 Section 429.132 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR CONSUMER PRODUCTS AND COMMERCIAL AND INDUSTRIAL EQUIPMENT Enforcement § 429.132 Compromise and settlement. (a) DOE may...

  9. 38 CFR 1.970 - Standards for compromise.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Standards for compromise. 1.970 Section 1.970 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS GENERAL PROVISIONS Referrals to Gao, Department of Justice, Or Irs § 1.970 Standards for compromise. Decisions of...

  10. 38 CFR 1.970 - Standards for compromise.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Standards for compromise. 1.970 Section 1.970 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS GENERAL PROVISIONS Referrals to Gao, Department of Justice, Or Irs § 1.970 Standards for compromise. Decisions of...

  11. 48 CFR 252.239-7000 - Protection against compromising emanations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Protection against... CLAUSES Text of Provisions And Clauses 252.239-7000 Protection against compromising emanations. As prescribed in 239.7103(a), use the following clause: Protection Against Compromising Emanations (JUN 2004)...

  12. 20 CFR 355.46 - Compromise or settlement.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Compromise or settlement. 355.46 Section 355.46 Employees' Benefits RAILROAD RETIREMENT BOARD ADMINISTRATIVE REMEDIES FOR FRAUDULENT CLAIMS OR STATEMENTS REGULATIONS UNDER THE PROGRAM FRAUD CIVIL REMEDIES ACT OF 1986 § 355.46 Compromise or settlement. (a) Parties may make offers of...

  13. 5 CFR 1312.30 - Loss or possible compromise.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., DOWNGRADING, DECLASSIFICATION AND SAFEGUARDING OF NATIONAL SECURITY INFORMATION Control and Accountability of Classified Information § 1312.30 Loss or possible compromise. Any person who has knowledge of the loss or possible compromise of classified information shall immediately secure the material and then report...

  14. 49 CFR 209.109 - Payment of penalty; compromise.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Payment of penalty; compromise. 209.109 Section... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD SAFETY ENFORCEMENT PROCEDURES Hazardous Materials Penalties Civil Penalties § 209.109 Payment of penalty; compromise. (a) Payment of a civil penalty may be made...

  15. 49 CFR 209.109 - Payment of penalty; compromise.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Payment of penalty; compromise. 209.109 Section... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD SAFETY ENFORCEMENT PROCEDURES Hazardous Materials Penalties Civil Penalties § 209.109 Payment of penalty; compromise. (a) Payment of a civil penalty may be made...

  16. 49 CFR 107.327 - Compromise and settlement.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Compromise and settlement. 107.327 Section 107.327 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... PROGRAM PROCEDURES Enforcement Compliance Orders and Civil Penalties § 107.327 Compromise and...

  17. 49 CFR 107.327 - Compromise and settlement.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Compromise and settlement. 107.327 Section 107.327 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... PROGRAM PROCEDURES Enforcement Compliance Orders and Civil Penalties § 107.327 Compromise and...

  18. 5 CFR 1215.32 - Compromise, suspension and termination.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Compromise, suspension and termination. 1215.32 Section 1215.32 Administrative Personnel MERIT SYSTEMS PROTECTION BOARD ORGANIZATION AND PROCEDURES DEBT MANAGEMENT Claims Collection § 1215.32 Compromise, suspension and termination. (a)...

  19. 19 CFR 161.5 - Compromise of Government claims.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 2 2014-04-01 2014-04-01 false Compromise of Government claims. 161.5 Section 161... Government claims. (a) Offer. An offer made pursuant to section 617, Tariff Act of 1930, as amended (19 U.S.C. 1617), in compromise of a Government claim arising under the Customs laws and the terms upon which...

  20. 27 CFR 70.449 - Offers in compromise.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Offers in compromise. 70.449 Section 70.449 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... Cartridges, and Explosives § 70.449 Offers in compromise. The procedures in the case of offers in...

  1. Cloning, characterization and sub-cellular localization of gamma subunit of T-complex protein-1 (chaperonin) from Leishmania donovani

    SciTech Connect

    Bhaskar,; Kumari, Neeti; Goyal, Neena

    2012-12-07

    Highlights: Black-Right-Pointing-Pointer The study presents cloning and characterization of TCP1{gamma} gene from L. donovani. Black-Right-Pointing-Pointer TCP1{gamma} is a subunit of T-complex protein-1 (TCP1), a chaperonin class of protein. Black-Right-Pointing-Pointer LdTCP{gamma} exhibited differential expression in different stages of promastigotes. Black-Right-Pointing-Pointer LdTCP{gamma} co-localized with actin, a cytoskeleton protein. Black-Right-Pointing-Pointer The data suggests that this gene may have a role in differentiation/biogenesis. Black-Right-Pointing-Pointer First report on this chapronin in Leishmania. -- Abstract: T-complex protein-1 (TCP1) complex, a chaperonin class of protein, ubiquitous in all genera of life, is involved in intracellular assembly and folding of various proteins. The gamma subunit of TCP1 complex (TCP1{gamma}), plays a pivotal role in the folding and assembly of cytoskeleton protein(s) as an individual or complexed with other subunits. Here, we report for the first time cloning, characterization and expression of the TCP1{gamma} of Leishmania donovani (LdTCP1{gamma}), the causative agent of Indian Kala-azar. Primary sequence analysis of LdTCP1{gamma} revealed the presence of all the characteristic features of TCP1{gamma}. However, leishmanial TCP1{gamma} represents a distinct kinetoplastid group, clustered in a separate branch of the phylogenic tree. LdTCP1{gamma} exhibited differential expression in different stages of promastigotes. The non-dividing stationary phase promastigotes exhibited 2.5-fold less expression of LdTCP1{gamma} as compared to rapidly dividing log phase parasites. The sub-cellular distribution of LdTCP1{gamma} was studied in log phase promastigotes by employing indirect immunofluorescence microscopy. The protein was present not only in cytoplasm but it was also localized in nucleus, peri-nuclear region, flagella, flagellar pocket and apical region. Co-localization of LdTCP1{gamma} with actin suggests

  2. A direct regulatory interaction between chaperonin TRiC and stress-responsive transcription factor HSF1.

    PubMed

    Neef, Daniel W; Jaeger, Alex M; Gomez-Pastor, Rocio; Willmund, Felix; Frydman, Judith; Thiele, Dennis J

    2014-11-01

    Heat shock transcription factor 1 (HSF1) is an evolutionarily conserved transcription factor that protects cells from protein-misfolding-induced stress and apoptosis. The mechanisms by which cytosolic protein misfolding leads to HSF1 activation have not been elucidated. Here, we demonstrate that HSF1 is directly regulated by TRiC/CCT, a central ATP-dependent chaperonin complex that folds cytosolic proteins. A small-molecule activator of HSF1, HSF1A, protects cells from stress-induced apoptosis, binds TRiC subunits in vivo and in vitro, and inhibits TRiC activity without perturbation of ATP hydrolysis. Genetic inactivation or depletion of the TRiC complex results in human HSF1 activation, and HSF1A inhibits the direct interaction between purified TRiC and HSF1 in vitro. These results demonstrate a direct regulatory interaction between the cytosolic chaperone machine and a critical transcription factor that protects cells from proteotoxicity, providing a mechanistic basis for signaling perturbations in protein folding to a stress-protective transcription factor. PMID:25437552

  3. Interactions between a luteovirus and the GroEL chaperonin protein of the symbiotic bacterium Buchnera aphidicola of aphids.

    PubMed

    Bouvaine, Sophie; Boonham, Neil; Douglas, Angela E

    2011-06-01

    Luteoviruses and poleroviruses are important plant viruses transmitted exclusively by aphids in a circulative manner via the aphid haemolymph. A chaperonin protein, GroEL, synthesized in aphids by a symbiotic bacterium, Buchnera aphidicola, is hypothesized to bind to virus particles in the haemolymph, thereby promoting transmission. To investigate this hypothesis, the GroEL-binding site for barley yellow dwarf virus (BYDV) was determined in vitro, and the abundance of GroEL protein in different aphid tissues was investigated. Virus binding to a peptide library representing the full GroEL molecule revealed a single binding site that coincides with the site that anchors two GroEL rings to form the native GroEL tetradecamer. In the functional form of the GroEL protein, virus binding would compete with the formation of the two GroEL rings. Using a mAb raised against a Buchnera-specific GroEL epitope, GroEL was detected in Buchnera cells by immunoblotting and immunocytochemistry, but not in the aphid haemolymph, fat body or gut. From the prediction here that GroEL-virus interactions are probably severely limited by competition with other GroEL molecules, and the evidence that GroEL is not available to interact with virus particles in vivo, it is concluded that GroEL-virus interactions are unlikely to contribute to virus transmission by aphids. PMID:21346031

  4. Intrinsic unfoldase/foldase activity of the chaperonin GroEL directly demonstrated using multinuclear relaxation-based NMR

    PubMed Central

    Libich, David S.; Tugarinov, Vitali; Clore, G. Marius

    2015-01-01

    The prototypical chaperonin GroEL assists protein folding through an ATP-dependent encapsulation mechanism. The details of how GroEL folds proteins remain elusive, particularly because encapsulation is not an absolute requirement for successful re/folding. Here we make use of a metastable model protein substrate, comprising a triple mutant of Fyn SH3, to directly demonstrate, by simultaneous analysis of three complementary NMR-based relaxation experiments (lifetime line broadening, dark state exchange saturation transfer, and Carr–Purcell–Meinboom–Gill relaxation dispersion), that apo GroEL accelerates the overall interconversion rate between the native state and a well-defined folding intermediate by about 20-fold, under conditions where the “invisible” GroEL-bound states have occupancies below 1%. This is largely achieved through a 500-fold acceleration in the folded-to-intermediate transition of the protein substrate. Catalysis is modulated by a kinetic deuterium isotope effect that reduces the overall interconversion rate between the GroEL-bound species by about 3-fold, indicative of a significant hydrophobic contribution. The location of the GroEL binding site on the folding intermediate, mapped from 15N, 1HN, and 13Cmethyl relaxation dispersion experiments, is composed of a prominent, surface-exposed hydrophobic patch. PMID:26124125

  5. Cloning, characterization and sub-cellular localization of gamma subunit of T-complex protein-1 (chaperonin) from Leishmania donovani.

    PubMed

    Bhaskar; Kumari, Neeti; Goyal, Neena

    2012-12-01

    T-complex protein-1 (TCP1) complex, a chaperonin class of protein, ubiquitous in all genera of life, is involved in intracellular assembly and folding of various proteins. The gamma subunit of TCP1 complex (TCP1γ), plays a pivotal role in the folding and assembly of cytoskeleton protein(s) as an individual or complexed with other subunits. Here, we report for the first time cloning, characterization and expression of the TCP1γ of Leishmania donovani (LdTCP1γ), the causative agent of Indian Kala-azar. Primary sequence analysis of LdTCP1γ revealed the presence of all the characteristic features of TCP1γ. However, leishmanial TCP1γ represents a distinct kinetoplastid group, clustered in a separate branch of the phylogenic tree. LdTCP1γ exhibited differential expression in different stages of promastigotes. The non-dividing stationary phase promastigotes exhibited 2.5-fold less expression of LdTCP1γ as compared to rapidly dividing log phase parasites. The sub-cellular distribution of LdTCP1γ was studied in log phase promastigotes by employing indirect immunofluorescence microscopy. The protein was present not only in cytoplasm but it was also localized in nucleus, peri-nuclear region, flagella, flagellar pocket and apical region. Co-localization of LdTCP1γ with actin suggests that, this gene may have a role in maintaining the structural dynamics of cytoskeleton of parasite. PMID:23137535

  6. Probing the Sequence of Conformationally-Induced Polarity Changes in the Molecular Chaperonin GroEL with Fluorescence Spectroscopy

    PubMed Central

    Kim, So Yeon; Semyonov, Alexander N.; Twieg, Robert J.; Horwich, Arthur L.; Frydman, Judith; Moerner, W. E.

    2006-01-01

    Hydrophobic interactions play a major role in binding non-native substrate proteins in the central cavity of the bacterial chaperonin GroEL. The sequence of local conformational changes by which GroEL and its cofactor GroES assist protein folding can be explored using the polarity-sensitive fluorescence probe Nile Red. A specific single-cysteine mutant of GroEL (Cys261), whose cysteine is located inside the central cavity at the apical region of the protein, was covalently labeled with synthetically prepared Nile Red maleimide (NR). Bulk fluorescence spectra of Cys261-NR were measured to examine the effects of binding of the stringent substrate, malate dehydrogenase (MDH), GroES, and nucleotide on the local environment of the probe. After binding denatured substrate, the fluorescence intensity increased by 32±7%, suggesting enhanced hydrophobicity at the position of the label. On the other hand, in the presence of ATP, the fluorescence intensity decreased by 13±3%, implying increased local polarity. In order to explore the sequence of local polarity changes, substrate, GroES, and various nucleotides were added in different orders; the resulting changes in emission intensity provide insight into the sequence of conformational changes occurring during GroEL-mediated protein folding. PMID:16375456

  7. The Chaperonin Containing TCP1 Complex (CCT/TRiC) Is Involved in Mediating Sperm-Oocyte Interaction

    PubMed Central

    Dun, Matthew D.; Smith, Nathan D.; Baker, Mark A.; Lin, Minjie; Aitken, R. John; Nixon, Brett

    2011-01-01

    Sperm-oocyte interactions are among the most remarkable processes in cell biology. These cellular recognition events are initiated by an exquisitely specific adhesion of free-swimming spermatozoa to the zona pellucida, an acellular matrix that surrounds the ovulated oocyte. Decades of research focusing on this interaction have led to the establishment of a widely held paradigm that the zona pellucida receptor is a single molecular entity that is constitutively expressed on the sperm cell surface. In contrast, we have employed the techniques of blue native-polyacrylamide gel electrophoresis, far Western blotting, and proximity ligation to secure the first direct evidence in support of a novel hypothesis that zona binding is mediated by multimeric sperm receptor complex(es). Furthermore, we show that one such multimeric association, comprising the chaperonin-containing TCP1 complex (CCT/TRiC) and a zona-binding protein, zona pellucida-binding protein 2, is present on the surface of capacitated spermatozoa and could account for the zona binding activity of these cells. Collectively, these data provide an important biochemical insight into the molecular basis of sperm-zona pellucida interaction and a plausible explanation for how spermatozoa gain their ability to fertilize. PMID:21880732

  8. 15 CFR 904.106 - Compromise of civil penalty.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... be sent to Agency counsel at the address specified in the NOVA. (c) Neither the existence of the... which a NOVA becomes final. (d) NOAA will not compromise, modify, or remit a civil penalty assessed,...

  9. 15 CFR 904.106 - Compromise of civil penalty.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... be sent to Agency counsel at the address specified in the NOVA. (c) Neither the existence of the... which a NOVA becomes final. (d) NOAA will not compromise, modify, or remit a civil penalty assessed,...

  10. 15 CFR 904.106 - Compromise of civil penalty.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... be sent to Agency counsel at the address specified in the NOVA. (c) Neither the existence of the... which a NOVA becomes final. (d) NOAA will not compromise, modify, or remit a civil penalty assessed,...

  11. 15 CFR 904.106 - Compromise of civil penalty.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... be sent to Agency counsel at the address specified in the NOVA. (c) Neither the existence of the... which a NOVA becomes final. (d) NOAA will not compromise, modify, or remit a civil penalty assessed,...

  12. 15 CFR 904.106 - Compromise of civil penalty.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... be sent to Agency counsel at the address specified in the NOVA. (c) Neither the existence of the... which a NOVA becomes final. (d) NOAA will not compromise, modify, or remit a civil penalty assessed,...

  13. Construction and characterization of the hetero-oligomer of the group II chaperonin from the hyperthermophilic archaeon, Thermococcus sp. strain KS-1.

    PubMed

    Sahlan, Muhamad; Kanzaki, Taro; Yohda, Masafumi

    2009-05-01

    The hyperthermophilic archaeon Thermococcus sp. strain KS-1 (T. KS-1) expresses two different chaperonin subunits, alpha and beta, for the folding of its proteins. The composition of the subunits in the hexadecameric double ring changes with temperature. The content of the beta subunit significantly increases according to the increase in temperature. The homo-oligomer of the beta subunit, Cpn beta, is more thermostable than that of the alpha subunit, Cpn alpha. Since Cpn alpha and Cpn beta also have different protein folding activities and interactions with prefoldin, the hetero-oligomer is thought to exhibit different characteristics according to the content of subunits. The hetero-oligomer of the T. KS-1 chaperonin has not been studied, however, because the alpha and beta subunits form hetero-oligomers of varying compositions when they are expressed simultaneously. In this study, we characterized the T. KS-1 chaperonin hetero-oligomer, Cpn alphabeta, containing both alpha and beta in the alternate order, which was constructed by the expression of alpha and beta subunits in a coordinated fashion and protease digestion. Cpn alphabeta protected citrate synthase from thermal aggregation, promoted the folding of acid-denatured GFP in an ATP-dependent manner, and exhibited an ATP-dependent conformational change. The yield of refolded GFP generated by Cpn alphabeta was almost equivalent to that generated by Cpn beta but lower than that generated by Cpn alpha. In contrast, Cpn alphabeta exhibited almost the same level of thermal stability as Cpn alpha, which was lower than that of Cpn beta. The affinity of Cpn alphabeta to prefoldin was found to be between those of Cpn alpha and Cpn beta, as expected. PMID:19229501

  14. Molecular Diagnostic Tools for Detection and Differentiation of Phytoplasmas Based on Chaperonin-60 Reveal Differences in Host Plant Infection Patterns

    PubMed Central

    Dumonceaux, Tim J.; Green, Margaret; Hammond, Christine; Perez, Edel; Olivier, Chrystel

    2014-01-01

    Phytoplasmas (‘Candidatus Phytoplasma’ spp.) are insect-vectored bacteria that infect a wide variety of plants, including many agriculturally important species. The infections can cause devastating yield losses by inducing morphological changes that dramatically alter inflorescence development. Detection of phytoplasma infection typically utilizes sequences located within the 16S–23S rRNA-encoding locus, and these sequences are necessary for strain identification by currently accepted standards for phytoplasma classification. However, these methods can generate PCR products >1400 bp that are less divergent in sequence than protein-encoding genes, limiting strain resolution in certain cases. We describe a method for accessing the chaperonin-60 (cpn60) gene sequence from a diverse array of ‘Ca.Phytoplasma’ spp. Two degenerate primer sets were designed based on the known sequence diversity of cpn60 from ‘Ca.Phytoplasma’ spp. and used to amplify cpn60 gene fragments from various reference samples and infected plant tissues. Forty three cpn60 sequences were thereby determined. The cpn60 PCR-gel electrophoresis method was highly sensitive compared to 16S-23S-targeted PCR-gel electrophoresis. The topology of a phylogenetic tree generated using cpn60 sequences was congruent with that reported for 16S rRNA-encoding genes. The cpn60 sequences were used to design a hybridization array using oligonucleotide-coupled fluorescent microspheres, providing rapid diagnosis and typing of phytoplasma infections. The oligonucleotide-coupled fluorescent microsphere assay revealed samples that were infected simultaneously with two subtypes of phytoplasma. These tools were applied to show that two host plants, Brassica napus and Camelina sativa, displayed different phytoplasma infection patterns. PMID:25551224

  15. Topographic Studies of the GroEL-GroES Chaperonin Complex by Chemical Cross-linking Using Diformyl Ethynylbenzene

    PubMed Central

    Trnka, Michael J.; Burlingame, A. L.

    2010-01-01

    -linking analysis of the 21-protein, ADP-bound GroEL-GroES chaperonin complex. Twenty-five unique sites of cross-linking were determined. PMID:20813910

  16. Specific cross-reactivity of antibodies raised against two major stress proteins, stress 70 and chaperonin 60, in diverse species

    SciTech Connect

    Sanders, B.M.; Martin, L.S.; Nakagawa, P.A. ); Hunter, D.A. . Biologisk Inst.); Miller, S. ); Ullrich, S.J. . National Cancer Inst.)

    1994-08-01

    Immunoblot analysis using several antibodies raised against two major families of stress proteins, stress 70 and chaperonin 60 (cpn60), which are highly conserved in mammals, was carried out in diverse species often used in environmental research, including molluscs, annelids, crustaceans, echinoderms, and fish. The study revealed surprisingly different patterns of antibody cross-reactivity among species. The monoclonal anti-stress 70 antibody (mAb) C92 was the least cross-reactive for all species tested. The mAbs anti-stress 70 N27, BRM-22, and 3a3 were more broadly cross-reactive, but their binding specifities to stress 70 isoforms in the diverse species tested did not correlate with one another or follow taxonomic lines. The polyclonal anti-stress 70 antibody reacted to proteins in the 70 to 74 kDa range in all fish examined and in most invertebrates. When a polyclonal antibody (pAb) raised against cpn60 from a moth was used as a probe, specific binding was observed with proteins in the 60 to 64 kDa range in all fish examined and in most invertebrates. However, the size and number of isoforms that reacted with the pAb were species specific. These data suggest that these two major stress protein families are less highly conserved in invertebrates and fish than in mammals. Therefore, to minimize misinterpretation when using antibodies in heterologous assays with species in which the stress response has not been well characterized, it is important to determine which isoforms of stress 70 react with a particular antibody and to take into account the differential regulation of each member of this multigene family.

  17. Assisted protein folding at low temperature: evolutionary adaptation of the Antarctic fish chaperonin CCT and its client proteins

    PubMed Central

    Cuellar, Jorge; Yébenes, Hugo; Parker, Sandra K.; Carranza, Gerardo; Serna, Marina; Valpuesta, José María; Zabala, Juan Carlos; Detrich, H. William

    2014-01-01

    ABSTRACT Eukaryotic ectotherms of the Southern Ocean face energetic challenges to protein folding assisted by the cytosolic chaperonin CCT. We hypothesize that CCT and its client proteins (CPs) have co-evolved molecular adaptations that facilitate CCT–CP interaction and the ATP-driven folding cycle at low temperature. To test this hypothesis, we compared the functional and structural properties of CCT–CP systems from testis tissues of an Antarctic fish, Gobionotothen gibberifrons (Lönnberg) (habitat/body T = −1.9 to +2°C), and of the cow (body T = 37°C). We examined the temperature dependence of the binding of denatured CPs (β-actin, β-tubulin) by fish and bovine CCTs, both in homologous and heterologous combinations and at temperatures between −4°C and 20°C, in a buffer conducive to binding of the denatured CP to the open conformation of CCT. In homologous combination, the percentage of G. gibberifrons CCT bound to CP declined linearly with increasing temperature, whereas the converse was true for bovine CCT. Binding of CCT to heterologous CPs was low, irrespective of temperature. When reactions were supplemented with ATP, G. gibberifrons CCT catalyzed the folding and release of actin at 2°C. The ATPase activity of apo-CCT from G. gibberifrons at 4°C was ∼2.5-fold greater than that of apo-bovine CCT, whereas equivalent activities were observed at 20°C. Based on these results, we conclude that the catalytic folding cycle of CCT from Antarctic fishes is partially compensated at their habitat temperature, probably by means of enhanced CP-binding affinity and increased flexibility of the CCT subunits. PMID:24659247

  18. Fitness Trade-Offs Determine the Role of the Molecular Chaperonin GroEL in Buffering Mutations

    PubMed Central

    Sabater-Muñoz, Beatriz; Prats-Escriche, Maria; Montagud-Martínez, Roser; López-Cerdán, Adolfo; Toft, Christina; Aguilar-Rodríguez, José; Wagner, Andreas; Fares, Mario A.

    2015-01-01

    Molecular chaperones fold many proteins and their mutated versions in a cell and can sometimes buffer the phenotypic effect of mutations that affect protein folding. Unanswered questions about this buffering include the nature of its mechanism, its influence on the genetic variation of a population, the fitness trade-offs constraining this mechanism, and its role in expediting evolution. Answering these questions is fundamental to understand the contribution of buffering to increase genetic variation and ecological diversification. Here, we performed experimental evolution, genome resequencing, and computational analyses to determine the trade-offs and evolutionary trajectories of Escherichia coli expressing high levels of the essential chaperonin GroEL. GroEL is abundantly present in bacteria, particularly in bacteria with large loads of deleterious mutations, suggesting its role in mutational buffering. We show that groEL overexpression is costly to large populations evolving in the laboratory, leading to groE expression decline within 66 generations. In contrast, populations evolving under the strong genetic drift characteristic of endosymbiotic bacteria avoid extinction or can be rescued in the presence of abundant GroEL. Genomes resequenced from cells evolved under strong genetic drift exhibited significantly higher tolerance to deleterious mutations at high GroEL levels than at native levels, revealing that GroEL is buffering mutations in these cells. GroEL buffered mutations in a highly diverse set of proteins that interact with the environment, including substrate and ion membrane transporters, hinting at its role in ecological diversification. Our results reveal the fitness trade-offs of mutational buffering and how genetic variation is maintained in populations. PMID:26116858

  19. Molecular diagnostic tools for detection and differentiation of phytoplasmas based on chaperonin-60 reveal differences in host plant infection patterns.

    PubMed

    Dumonceaux, Tim J; Green, Margaret; Hammond, Christine; Perez, Edel; Olivier, Chrystel

    2014-01-01

    Phytoplasmas ('Candidatus Phytoplasma' spp.) are insect-vectored bacteria that infect a wide variety of plants, including many agriculturally important species. The infections can cause devastating yield losses by inducing morphological changes that dramatically alter inflorescence development. Detection of phytoplasma infection typically utilizes sequences located within the 16S-23S rRNA-encoding locus, and these sequences are necessary for strain identification by currently accepted standards for phytoplasma classification. However, these methods can generate PCR products >1400 bp that are less divergent in sequence than protein-encoding genes, limiting strain resolution in certain cases. We describe a method for accessing the chaperonin-60 (cpn60) gene sequence from a diverse array of 'Ca.Phytoplasma' spp. Two degenerate primer sets were designed based on the known sequence diversity of cpn60 from 'Ca.Phytoplasma' spp. and used to amplify cpn60 gene fragments from various reference samples and infected plant tissues. Forty three cpn60 sequences were thereby determined. The cpn60 PCR-gel electrophoresis method was highly sensitive compared to 16S-23S-targeted PCR-gel electrophoresis. The topology of a phylogenetic tree generated using cpn60 sequences was congruent with that reported for 16S rRNA-encoding genes. The cpn60 sequences were used to design a hybridization array using oligonucleotide-coupled fluorescent microspheres, providing rapid diagnosis and typing of phytoplasma infections. The oligonucleotide-coupled fluorescent microsphere assay revealed samples that were infected simultaneously with two subtypes of phytoplasma. These tools were applied to show that two host plants, Brassica napus and Camelina sativa, displayed different phytoplasma infection patterns. PMID:25551224

  20. Identification of Staphylococcus species and subspecies by the chaperonin 60 gene identification method and reverse checkerboard hybridization.

    PubMed Central

    Goh, S H; Santucci, Z; Kloos, W E; Faltyn, M; George, C G; Driedger, D; Hemmingsen, S M

    1997-01-01

    A previous study (S. H. Goh et al., J. Clin. Microbiol. 34:818-823, 1996) demonstrated that a 600-bp region of the chaperonin 60 (Cpn60) genes from various bacterial isolates could be amplified by PCR with a pair of degenerate primers and that the products could be used as species-specific probes for Staphylococcus aureus, S. epidermidis, S. haemolyticus, S. lugdunensis, S. saprophyticus, and S. schleiferi. To further validate the utility of bacterial Cpn60 genes as universal targets for bacterial identification (ID), reverse checkerboard chemiluminescent hybridization experiments were performed with DNA probes from 34 different Staphylococcus species and subspecies. With the exception of probes from the Cpn60 genes of S. intermedius and S. delphini, which cross hybridized, all were species specific. Two subspecies of both S. capitis and S. cohnii were differentiated from one another, while DNAs from the two S. schleiferi subspecies cross hybridized. When 40 known Staphylococcus isolates were tested in a blind experiment by the Cpn60 gene method, 36 strains, representing six species and one subspecies (S. sciuri, S. caseolyticus, S. hominis, S. warneri, S. hyicus, S. haemolyticus, and S. capitis subsp. ureolyticus), were correctly identified. DNA from the four remaining isolates, known to be S. hyicus bovine strains, failed to hybridize to DNA from the S. hyicus target strain or any other Staphylococcus species. However, DNAs from these S. hyicus isolates did cross hybridize with each other. New DNA sequence data and evidence from previous studies suggest some genetic divergence between the two groups of S. hyicus isolates. Our results demonstrate that this Cpn60 gene-based ID method has the potential to be a basic method for bacterial ID. Studies are in progress to further validate the utility of this Cpn60 gene system for ID of Staphylococcus and other genera, including those of slow-growing microorganisms. PMID:9399505

  1. The role of the Chaperonin containing t-complex polypeptide 1, subunit 8 (CCT8) in B-cell non-Hodgkin's lymphoma.

    PubMed

    Yin, Haibing; Miao, Xiaobing; Wu, Yaxun; Wei, Yingze; Zong, Guijuan; Yang, Shuyun; Chen, Xudong; Zheng, Guihua; Zhu, Xinghua; Guo, Yan; Li, Chunsun; Chen, Yali; Wang, Yuchan; He, Song

    2016-06-01

    The chaperonin containing t-complex polypeptide 1 (CCT) is known to mediate folding of proteins. CCT, subunit 8 (CCT8), is the θ subunit of CCT complex chaperonin. CCT8 has been reported to be dysregulated in several tumor tissues. In this study, we investigated the role of CCT8 in B-cell non-Hodgkin's lymphoma (NHL). Clinically, the expression levels of CCT8 in reactive lymphoid hyperplasia (RLH) and B-cell NHL specimens were investigated using immunohistochemical analysis. We found that CCT8 was highly expressed in proliferating germinal center cells compared with the quiescent cells of the follicular mantle zone. Furthermore, CCT8 was highly expressed in progressive lymphomas than in indolent lymphomas. Kaplan-Meier curve showed that high expression of CCT8 was significantly associated with shorter overall survival in patients with diffuse large B-cell lymphoma. Moreover, we demonstrated that CCT8 could promote the proliferation of B-cell NHL cells. In addition, we found that CCT8 could accelerate the G1/S transition in B-cell NHL. Finally, we demonstrated that overexpression of CCT8 could reverse cell adhesion-mediated drug resistance (CAM-DR) phenotype. Our study may shed new insights into the important role of CCT8 in cancer development. PMID:27101149

  2. Vaccinia-Related Kinase 2 Controls the Stability of the Eukaryotic Chaperonin TRiC/CCT by Inhibiting the Deubiquitinating Enzyme USP25

    PubMed Central

    Kim, Sangjune; Lee, Dohyun; Lee, Juhyun; Song, Haengjin; Kim, Hyo-Jin

    2015-01-01

    Molecular chaperones monitor the proper folding of misfolded proteins and function as the first line of defense against mutant protein aggregation in neurodegenerative diseases. The eukaryotic chaperonin TRiC is a potent suppressor of mutant protein aggregation and toxicity in early stages of disease progression. Elucidation of TRiC functional regulation will enable us to better understand the pathological mechanisms of neurodegeneration. We have previously shown that vaccinia-related kinase 2 (VRK2) downregulates TRiC protein levels through the ubiquitin-proteasome system by recruiting the E3 ligase COP1. However, although VRK2 activity was necessary in TRiC downregulation, the phosphorylated substrate was not determined. Here, we report that USP25 is a novel TRiC interacting protein that is also phosphorylated by VRK2. USP25 catalyzed deubiquitination of the TRiC protein and stabilized the chaperonin, thereby reducing accumulation of misfolded polyglutamine protein aggregates. Notably, USP25 deubiquitinating activity was suppressed when VRK2 phosphorylated the Thr680, Thr727, and Ser745 residues. Impaired USP25 deubiquitinating activity after VRK2-mediated phosphorylation may be a critical pathway in TRiC protein destabilization. PMID:25755282

  3. OsCpn60α1, Encoding the Plastid Chaperonin 60α Subunit, Is Essential for Folding of rbcL

    PubMed Central

    Kim, Sung-Ryul; Yang, Jung-Il; An, Gynheung

    2013-01-01

    Chaperonins are involved in protein-folding. The rice genome encodes six plastid chaperonin subunits (Cpn60) - three α and three β. Our study showed that they were differentially expressed during normal plant development. Moreover, five were induced by heat stress (42°C) but not by cold (10°C). The oscpn60α1 mutant had a pale-green phenotype at the seedling stage and development ceased after the fourth leaf appeared. Transiently expressed OsCpn60α1:GFP fusion protein was localized to the chloroplast stroma. Immuno-blot analysis indicated that the level of Rubisco large subunit (rbcL) was severely reduced in the mutant while levels were unchanged for some imported proteins, e.g., stromal heat shock protein 70 (Hsp70) and chlorophyll a/b binding protein 1 (Lhcb1). This demonstrated that OsCpn60α1 is required for the folding of rbcL and that failure of that process is seedling-lethal. PMID:23620301

  4. Alchemy or Science? Compromising Archaeology in the Deep Sea

    NASA Astrophysics Data System (ADS)

    Adams, Jonathan

    2007-06-01

    In the torrid debate between archaeology and treasure hunting, compromise is often suggested as the pragmatic solution, especially for archaeology carried out either in deep water or beyond the constraints that commonly regulate such activities in territorial seas. Both the wisdom and the need for such compromise have even been advocated by some archaeologists, particularly in forums such as the internet and conferences. This paper argues that such a compromise is impossible, not in order to fuel confrontation but simply because of the nature of any academic discipline. We can define what archaeology is in terms of its aims, theories, methods and ethics, so combining it with an activity founded on opposing principles must transform it into something else. The way forward for archaeology in the deep sea does not lie in a contradictory realignment of archaeology’s goals but in collaborative research designed to mesh with emerging national and regional research and management plans.

  5. 40 CFR 27.46 - Compromise or settlement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Compromise or settlement. 27.46 Section 27.46 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GENERAL PROGRAM FRAUD CIVIL REMEDIES... at any time after the date on which the reviewing official is permitted to issue a complaint...

  6. 14 CFR 1261.414 - Compromise of claims.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... the Claims Collection Litigation Report. See § 1261.417(e) or 4 CFR 105.2(b). Claims for which the... Department of Justice for litigation. The Comptroller General may exercise such compromise authority with... other debtors that resistance to payment is not likely to succeed. (f) Enforcement policy....

  7. 14 CFR 1261.414 - Compromise of claims.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... the Claims Collection Litigation Report. See § 1261.417(e) or 4 CFR 105.2(b). Claims for which the... Department of Justice for litigation. The Comptroller General may exercise such compromise authority with... other debtors that resistance to payment is not likely to succeed. (f) Enforcement policy....

  8. 14 CFR 1261.414 - Compromise of claims.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... the Claims Collection Litigation Report. See § 1261.417(e) or 4 CFR 105.2(b). Claims for which the... Department of Justice for litigation. The Comptroller General may exercise such compromise authority with... other debtors that resistance to payment is not likely to succeed. (f) Enforcement policy....

  9. 14 CFR § 1261.414 - Compromise of claims.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... the Claims Collection Litigation Report. See § 1261.417(e) or 4 CFR 105.2(b). Claims for which the... Department of Justice for litigation. The Comptroller General may exercise such compromise authority with... other debtors that resistance to payment is not likely to succeed. (f) Enforcement policy....

  10. 14 CFR 1261.414 - Compromise of claims.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... the Claims Collection Litigation Report. See § 1261.417(e) or 4 CFR 105.2(b). Claims for which the... Department of Justice for litigation. The Comptroller General may exercise such compromise authority with... other debtors that resistance to payment is not likely to succeed. (f) Enforcement policy....

  11. Whatever It Takes: Health Compromising Behaviors in Female Athletes

    ERIC Educational Resources Information Center

    Waldron, Jennifer J.; Krane, Vikki

    2005-01-01

    The power and performance model of sport stresses a sport ethic of doing "whatever it takes" to win (Coakley, 2004). Uncritical acceptance of this model may lead to various health-compromising behaviors. Employing achievement goal theory, we examine why female athletes may adopt the power and performance approach. An ego motivational climate and a…

  12. 49 CFR 209.109 - Payment of penalty; compromise.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Payment of penalty; compromise. 209.109 Section 209.109 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD SAFETY ENFORCEMENT PROCEDURES Hazardous Materials Penalties Civil Penalties § 209.109 Payment...

  13. Implant surgery in healthy compromised patients-review of literature.

    PubMed

    Gheorghiu, I M; Stoian, I M

    2014-01-01

    Systemic diseases are of major importance in terms of prosthetic restorations supported by dental implants in healthy compromised patients. Each treatment stage from conception of the treatment plan to the long-term monitoring is under the necessity of the interdisciplinary approach to the underlying disease. PMID:25870664

  14. 47 CFR 1.1915 - Exploration of compromise.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Federal Claims Collection Standards (31 CFR part 902). The Commission will also consider a request... justification of the offer and addressing the bases for compromise at 31 CFR 902.2. Debtors will provide full... evaluate an offer, using the factors set forth in 31 CFR 902.2 and, as appropriate, refer the offer...

  15. Evil Searching: Compromise and Recompromise of Internet Hosts for Phishing

    NASA Astrophysics Data System (ADS)

    Moore, Tyler; Clayton, Richard

    Attackers compromise web servers in order to host fraudulent content, such as malware and phishing websites. While the techniques used to compromise websites are widely discussed and categorized, analysis of the methods used by attackers to identify targets has remained anecdotal. In this paper, we study the use of search engines to locate potentially vulnerable hosts. We present empirical evidence from the logs of websites used for phishing to demonstrate attackers’ widespread use of search terms which seek out susceptible web servers. We establish that at least 18% of website compromises are triggered by these searches. Many websites are repeatedly compromised whenever the root cause of the vulnerability is not addressed. We find that 19% of phishing websites are recompromised within six months, and the rate of recompromise is much higher if they have been identified through web search. By contrast, other public sources of information about phishing websites are not currently raising recompromise rates; we find that phishing websites placed onto a public blacklist are recompromised no more frequently than websites only known within closed communities.

  16. Time-to-Compromise Model for Cyber Risk Reduction Estimation

    SciTech Connect

    Miles A. McQueen; Wayne F. Boyer; Mark A. Flynn; George A. Beitel

    2005-09-01

    We propose a new model for estimating the time to compromise a system component that is visible to an attacker. The model provides an estimate of the expected value of the time-to-compromise as a function of known and visible vulnerabilities, and attacker skill level. The time-to-compromise random process model is a composite of three subprocesses associated with attacker actions aimed at the exploitation of vulnerabilities. In a case study, the model was used to aid in a risk reduction estimate between a baseline Supervisory Control and Data Acquisition (SCADA) system and the baseline system enhanced through a specific set of control system security remedial actions. For our case study, the total number of system vulnerabilities was reduced by 86% but the dominant attack path was through a component where the number of vulnerabilities was reduced by only 42% and the time-to-compromise of that component was increased by only 13% to 30% depending on attacker skill level.

  17. CONCENTRATED AMBIENT PARTICULATE STUDIES IN HEALTHY AND COMPROMISED RODENTS

    EPA Science Inventory


    CONCENTRATED AMBIENT PARTICULATE STUDIES IN HEALTHY AND COMPROMISED RODENTS. WP Watkinson1, LB Wichers2, JP Nolan1, DW Winsett1, UP Kodavanti1, MCJ Schladweiler1, LC Walsh1, ER Lappi1, D Terrell1, R Slade1, AD Ledbetter1, and DL Costa1. 1USEPA, ORD/NHEERL/ETD/PTB, RTP, NC, US...

  18. Vehicle influence on permeation through intact and compromised skin.

    PubMed

    Gujjar, Meera; Banga, Ajay K

    2014-09-10

    The purpose of this study was to compare the transdermal permeation of a model compound, diclofenac diethylamine, from a hydrophilic and lipophilic vehicle across in vitro models simulating compromised skin. Mineral oil served as a lipophilic vehicle while 10mM phosphate buffered saline served as a hydrophilic vehicle. Compromised skin was simulated by tape stripping, delipidization, or microneedle application and compared with intact skin as a control. Transepidermal water loss was measured to assess barrier function. Skin compromised with tape stripping and delipidization significantly (p<0.05) increased permeation of diclofenac diethylamine compared to intact and microneedle treated skin with phosphate buffered saline vehicle. A similar trend in permeation was observed with mineral oil as the vehicle. For both vehicles, permeation across skin increased in the same order and correlated with degree of barrier impairment as indicated by transepidermal water loss values: intactcompromised skin. PMID:24979534

  19. 32 CFR 2400.33 - Loss or possible compromise.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 2400.33 National Defense Other Regulations Relating to National Defense OFFICE OF SCIENCE AND TECHNOLOGY POLICY REGULATIONS TO IMPLEMENT E.O. 12356; OFFICE OF SCIENCE AND TECHNOLOGY POLICY INFORMATION... measures taken to negate or minimize any adverse effect of the compromise. (b) The Security Officer...

  20. 32 CFR 2400.33 - Loss or possible compromise.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 2400.33 National Defense Other Regulations Relating to National Defense OFFICE OF SCIENCE AND TECHNOLOGY POLICY REGULATIONS TO IMPLEMENT E.O. 12356; OFFICE OF SCIENCE AND TECHNOLOGY POLICY INFORMATION... measures taken to negate or minimize any adverse effect of the compromise. (b) The Security Officer...

  1. 45 CFR 1177.12 - Compromise, suspension and termination.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... THE ARTS AND THE HUMANITIES NATIONAL ENDOWMENT FOR THE HUMANITIES CLAIMS COLLECTION § 1177.12 Compromise, suspension and termination. (a) The Chairperson of the National Endowment for the Humanities or... available to the public. (b) The Chairperson of the National Endowment for the Humanities may...

  2. 45 CFR 1177.12 - Compromise, suspension and termination.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... THE ARTS AND THE HUMANITIES NATIONAL ENDOWMENT FOR THE HUMANITIES CLAIMS COLLECTION § 1177.12 Compromise, suspension and termination. (a) The Chairperson of the National Endowment for the Humanities or... available to the public. (b) The Chairperson of the National Endowment for the Humanities may...

  3. 45 CFR 1177.12 - Compromise, suspension and termination.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... THE ARTS AND THE HUMANITIES NATIONAL ENDOWMENT FOR THE HUMANITIES CLAIMS COLLECTION § 1177.12 Compromise, suspension and termination. (a) The Chairperson of the National Endowment for the Humanities or... available to the public. (b) The Chairperson of the National Endowment for the Humanities may...

  4. 45 CFR 1177.12 - Compromise, suspension and termination.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... THE ARTS AND THE HUMANITIES NATIONAL ENDOWMENT FOR THE HUMANITIES CLAIMS COLLECTION § 1177.12 Compromise, suspension and termination. (a) The Chairperson of the National Endowment for the Humanities or... available to the public. (b) The Chairperson of the National Endowment for the Humanities may...

  5. 45 CFR 1177.12 - Compromise, suspension and termination.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... THE ARTS AND THE HUMANITIES NATIONAL ENDOWMENT FOR THE HUMANITIES CLAIMS COLLECTION § 1177.12 Compromise, suspension and termination. (a) The Chairperson of the National Endowment for the Humanities or... available to the public. (b) The Chairperson of the National Endowment for the Humanities may...

  6. 32 CFR 2400.33 - Loss or possible compromise.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 6 2013-07-01 2013-07-01 false Loss or possible compromise. 2400.33 Section 2400.33 National Defense Other Regulations Relating to National Defense OFFICE OF SCIENCE AND TECHNOLOGY POLICY REGULATIONS TO IMPLEMENT E.O. 12356; OFFICE OF SCIENCE AND TECHNOLOGY POLICY...

  7. 26 CFR 601.203 - Offers in compromise.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... STATEMENT OF PROCEDURAL RULES Rulings and Other Specific Matters § 601.203 Offers in compromise. (a) General... Department of Justice for prosecution or defense. Certain functions of the Commissioner with respect to... prosecution are pending in the Office of the Chief Counsel, the Department of Justice, or in an office of...

  8. 7 CFR 1956.124 - Compromise and adjustment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 14 2012-01-01 2012-01-01 false Compromise and adjustment. 1956.124 Section 1956.124 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, RURAL BUSINESS-COOPERATIVE SERVICE, RURAL UTILITIES SERVICE, AND FARM SERVICE AGENCY, DEPARTMENT OF AGRICULTURE (CONTINUED) PROGRAM REGULATIONS...

  9. An Item Response Model for Characterizing Test Compromise.

    ERIC Educational Resources Information Center

    Segall, Daniel O.

    2002-01-01

    Developed an item response model for characterizing test-compromise that enables the estimation of item preview and score-gain distributions. In the approach, models parameters and posterior distributions are estimated by Markov Chain Monte Carlo procedures. Simulation study results suggest that when at least some test items are known to be…

  10. Chaperonin containing T-complex polypeptide subunit eta (CCT-eta) is a specific regulator of fibroblast motility and contractility.

    PubMed

    Satish, Latha; Johnson, Sandra; Wang, James H-C; Post, J Christopher; Ehrlich, Garth D; Kathju, Sandeep

    2010-01-01

    Integumentary wounds in mammalian fetuses heal without scar; this scarless wound healing is intrinsic to fetal tissues and is notable for absence of the contraction seen in postnatal (adult) wounds. The precise molecular signals determining the scarless phenotype remain unclear. We have previously reported that the eta subunit of the chaperonin containing T-complex polypeptide (CCT-eta) is specifically reduced in healing fetal wounds in a rabbit model. In this study, we examine the role of CCT-eta in fibroblast motility and contractility, properties essential to wound healing and scar formation. We demonstrate that CCT-eta (but not CCT-beta) is underexpressed in fetal fibroblasts compared to adult fibroblasts. An in vitro wound healing assay demonstrated that adult fibroblasts showed increased cell migration in response to epidermal growth factor (EGF) and platelet derived growth factor (PDGF) stimulation, whereas fetal fibroblasts were unresponsive. Downregulation of CCT-eta in adult fibroblasts with short inhibitory RNA (siRNA) reduced cellular motility, both basal and growth factor-induced; in contrast, siRNA against CCT-beta had no such effect. Adult fibroblasts were more inherently contractile than fetal fibroblasts by cellular traction force microscopy; this contractility was increased by treatment with EGF and PDGF. CCT-eta siRNA inhibited the PDGF-induction of adult fibroblast contractility, whereas CCT-beta siRNA had no such effect. In each of these instances, the effect of downregulating CCT-eta was to modulate the behavior of adult fibroblasts so as to more closely approximate the characteristics of fetal fibroblasts. We next examined the effect of CCT-eta modulation on alpha-smooth muscle actin (alpha-SMA) expression, a gene product well known to play a critical role in adult wound healing. Fetal fibroblasts were found to constitutively express less alpha-SMA than adult cells. Reduction of CCT-eta with siRNA had minimal effect on cellular beta-actin but

  11. Chaperonin CCT-Mediated AIB1 Folding Promotes the Growth of ERα-Positive Breast Cancer Cells on Hard Substrates

    PubMed Central

    Chen, Li; Zhang, Ze; Qiu, Juhui; Zhang, Lingling; Luo, Xiangdong; Jang, Jun

    2014-01-01

    Clinical observations have revealed a strong association between estrogen receptor alpha (ERα)-positive tumors and the development of bone metastases, however, the mechanism underlying this association remains unknown. We cultured MCF-7 (ERα-positive) on different rigidity substrates. Compared with cells grown on more rigid substrates (100 kPa), cells grown on soft substrates (10 kPa) exhibited reduced spreading ability, a lower ratio of cells in the S and G2/M cell cycle phases, and a decreased proliferation rate. Using stable isotope labeling by amino acids (SILAC), we further compared the whole proteome of MCF-7 cells grown on substrates of different rigidity (10 and 100 kPa), and found that the expression of eight members of chaperonin CCT increased by at least 2-fold in the harder substrate. CCT folding activity was increased in the hard substrate compared with the soft substrates. Amplified in breast cancer 1 (AIB1), was identified in CCT immunoprecipitates. CCT folding ability of AIB1 increased on 100-kPa substrate compared with 10- and 30-kPa substrates. Moreover, using mammalian two-hybrid protein-protein interaction assays, we found that the polyglutamine repeat sequence of the AIB1 protein was essential for interaction between CCTζ and AIB1. CCTζ-mediated AIB1 folding affects the cell area spreading, growth rate, and cell cycle. The expressions of the c-myc, cyclin D1, and PgR genes were higher on hard substrates than on soft substrate in both MCF-7 and T47D cells. ERα and AIB1 could up-regulate the mRNA and protein expression levels of the c-myc, cyclin D1, and PgR genes, and that 17 β-estradiol could enhance this effects. Conversely, 4-hydroxytamoxifen, could inhibit these effects. Taken together, our studies demonstrate that some ERα-positive breast cancer cells preferentially grow on more rigid substrates. CCT-mediated AIB1 folding appears to be involved in the rigidity response of breast cancer cells, which provides novel insight into the

  12. Securing Single Points of Compromise (SPoC)

    SciTech Connect

    Belangia, David Warren

    2015-06-25

    Securing the Single Points of Compromise that provide central services to the institution’s environment is paramount to success when trying to protect the business. (Fisk, 2014) Time Based Security mandates protection (erecting and ensuring effective controls) that last longer than the time to detect and react to a compromise. When enterprise protections fail, providing additional layered controls for these central services provides more time to detect and react. While guidance is readily available for securing the individual critical asset, protecting these assets as a group is not often discussed. Using best business practices to protect these resources as individual assets while leveraging holistic defenses for the group increases the opportunity to maximize protection time, allowing detection and reaction time for the SPoCs that is commensurate with the inherent risk of these centralized services.

  13. A technique to salvage endodontically compromised maxillary anterior tooth.

    PubMed

    Comut, Alper; Foran, Denise; Cunningham, Ralph P

    2014-01-01

    A complication of endodontic treatment is over-preparation of the tooth structure in an attempt to access calcified pulp chambers and root canals. This could result in thin root walls that might compromise the long-term prognosis of the tooth. There are various treatment options when such a complication occurs, among them, extraction of the compromised tooth and its replacement with a dental implant. This clinical report describes a nonsurgical, multidisciplinary treatment alternative where a maxillary anterior tooth with a thinned root wall was successfully saved by repairing the damaged root to its original thickness using a composite resin material and subsequently restoring with a cast post and core and a crown. PMID:24654367

  14. Creating clones, kids & chimera: liberal democratic compromise at the crossroads.

    PubMed

    Adams, Nathan A

    2004-01-01

    The objective of this article is to find middle ground between the supporters and opponents of biotechnology by perpetuating the existing legal compromise pertaining to the complete range of health and welfare doctrines relevant to the biotechnological industry. The author aspires neither to add to nor detract from this liberal democratic consensus, but to preserve its constitutive balance between positivism and natural law and over-regulation and under-regulation in the hopes of stabilizing new political fault lines developing around the few biotechnological innovations already grabbing headlines. The most feasible solution is to extend the existing liberal democratic compromise with respect to equal protection, reproductive rights, the First Amendment, human subject experimentation, patent law, and parental rights. This includes banning or monopolizing certain biotechnologies and extending substantive special respect to the ex vivo living human embryo. Biotechnology must not be left to regulate itself. PMID:15382747

  15. Potential Soviet compromise on ballistic missile defense. Final report

    SciTech Connect

    Nguyen, H.P.

    1989-11-01

    The body of this research memorandum was written before the Baker-Shevardnadze meeting in Wyoming. It presented evidence suggesting that the Soviet Union might agree to a compromise at the Wyoming meeting that defers the issue of ballistic missile defense (BMD) negotiations to a later stage in arms reductions, thus facilitating a first-stage cut in offensive arms without an explicit Soviet endorsement of the Strategic Defense Initiative (SDI). Through this compromise, offensive arms reductions should first be delinked from an agreement on BMD, and then be relinked during the second stage of deeper cuts. Therefore, negotiations on limiting BMD systems, though deterred, are deemed inevitable if the U.S. persists in deploying a strategic defense system (SDS). Moreover, some Soviet arms controllers already look beyond the first stage to the prospect of negotiated transition into a strategic defense environment (i.e., a reliance on defensive deterrence). In this approach, Wyoming, then, was expected to be only a first move in the Soviet negotiating strategy for a grand compromise on strategic defense. As explained in the afterword added to the paper, the actual events at Wyoming seem consistent with that interpretation.

  16. Misfolded forms of glyceraldehyde-3-phosphate dehydrogenase interact with GroEL and inhibit chaperonin-assisted folding of the wild-type enzyme.

    PubMed

    Polyakova, Oxana V; Roitel, Olivier; Asryants, Regina A; Poliakov, Alexei A; Branlant, Guy; Muronetz, Vladimir I

    2005-04-01

    We studied the interaction of chaperonin GroEL with different misfolded forms of tetrameric phosphorylating glyceraldehyde-3-phosphate dehydrogenase (GAPDH): (1) GAPDH from rabbit muscles with all SH-groups modified by 5,5'-dithiobis(2-nitrobenzoate); (2) O-R-type dimers of mutant GAPDH from Bacillus stearothermophilus with amino acid substitutions Y283V, D282G, and Y283V/W84F, and (3) O-P-type dimers of mutant GAPDH from B. stearothermophilus with amino acid substitutions Y46G/S48G and Y46G/R52G. It was shown that chemically modified GAPDH and the O-R-type mutant dimers bound to GroEL with 1:1 stoichiometry and dissociation constants K(d) of 0.4 and 0.9 muM, respectively. A striking feature of the resulting complexes with GroEL was their stability in the presence of Mg-ATP. Chemically modified GAPDH and the O-R-type mutant dimers inhibited GroEL-assisted refolding of urea-denatured wild-type GAPDH from B. stearothermophilus but did not affect its spontaneous reactivation. In contrast to the O-R-dimers, the O-P-type mutant dimers neither bound nor affected GroEL-assisted refolding of the wild-type GAPDH. Thus, we suggest that interaction of GroEL with certain types of misfolded proteins can result in the formation of stable complexes and the impairment of chaperonin activity. PMID:15741339

  17. Misfolded forms of glyceraldehyde-3-phosphate dehydrogenase interact with GroEL and inhibit chaperonin-assisted folding of the wild-type enzyme

    PubMed Central

    Polyakova, Oxana V.; Roitel, Olivier; Asryants, Regina A.; Poliakov, Alexei A.; Branlant, Guy; Muronetz, Vladimir I.

    2005-01-01

    We studied the interaction of chaperonin GroEL with different misfolded forms of tetrameric phosphorylating glyceraldehyde-3-phosphate dehydrogenase (GAPDH): (1) GAPDH from rabbit muscles with all SH-groups modified by 5,5′-dithiobis(2-nitrobenzoate); (2) O-R-type dimers of mutant GAPDH from Bacillus stearothermophilus with amino acid substitutions Y283V, D282G, and Y283V/W84F, and (3) O-P-type dimers of mutant GAPDH from B. stearothermophilus with amino acid substitutions Y46G/S48G and Y46G/R52G. It was shown that chemically modified GAPDH and the O-R-type mutant dimers bound to GroEL with 1:1 stoichiometry and dissociation constants Kd of 0.4 and 0.9 μM, respectively. A striking feature of the resulting complexes with GroEL was their stability in the presence of Mg-ATP. Chemically modified GAPDH and the O-R-type mutant dimers inhibited GroEL-assisted refolding of urea-denatured wild-type GAPDH from B. stearothermophilus but did not affect its spontaneous reactivation. In contrast to the O-R-dimers, the O-P-type mutant dimers neither bound nor affected GroEL-assisted refolding of the wild-type GAPDH. Thus, we suggest that interaction of GroEL with certain types of misfolded proteins can result in the formation of stable complexes and the impairment of chaperonin activity. PMID:15741339

  18. Identification of a novel BBS gene (BBS12) highlights the major role of a vertebrate-specific branch of chaperonin-related proteins in Bardet-Biedl syndrome.

    PubMed

    Stoetzel, Corinne; Muller, Jean; Laurier, Virginie; Davis, Erica E; Zaghloul, Norann A; Vicaire, Serge; Jacquelin, Cecile; Plewniak, Frederic; Leitch, Carmen C; Sarda, Pierre; Hamel, Christian; de Ravel, Thomy J L; Lewis, Richard Alan; Friederich, Evelyne; Thibault, Christelle; Danse, Jean-Marc; Verloes, Alain; Bonneau, Dominique; Katsanis, Nicholas; Poch, Olivier; Mandel, Jean-Louis; Dollfus, Helene

    2007-01-01

    Bardet-Biedl syndrome (BBS) is primarily an autosomal recessive ciliopathy characterized by progressive retinal degeneration, obesity, cognitive impairment, polydactyly, and kidney anomalies. The disorder is genetically heterogeneous, with 11 BBS genes identified to date, which account for ~70% of affected families. We have combined single-nucleotide-polymorphism array homozygosity mapping with in silico analysis to identify a new BBS gene, BBS12. Patients from two Gypsy families were homozygous and haploidentical in a 6-Mb region of chromosome 4q27. FLJ35630 was selected as a candidate gene, because it was predicted to encode a protein with similarity to members of the type II chaperonin superfamily, which includes BBS6 and BBS10. We found pathogenic mutations in both Gypsy families, as well as in 14 other families of various ethnic backgrounds, indicating that BBS12 accounts for approximately 5% of all BBS cases. BBS12 is vertebrate specific and, together with BBS6 and BBS10, defines a novel branch of the type II chaperonin superfamily. These three genes are characterized by unusually rapid evolution and are likely to perform ciliary functions specific to vertebrates that are important in the pathophysiology of the syndrome, and together they account for about one-third of the total BBS mutational load. Consistent with this notion, suppression of each family member in zebrafish yielded gastrulation-movement defects characteristic of other BBS morphants, whereas simultaneous suppression of all three members resulted in severely affected embryos, possibly hinting at partial functional redundancy within this protein family. PMID:17160889

  19. Video-assisted thoracoscopy in compromised pediatric patients.

    PubMed

    Gamba, Piergiorgio; Midrio, Paola; Betalli, Pietro; Snijders, Deborah; Leon, Francesco Fascetti

    2010-02-01

    The use of video-assisted techniques (VATs) in the paediatric field has become increasingly more frequent, based on reports of prompter recovery following VATs in respect to standard techniques. Specific advantages have been documented, in particular for pediatric patients undergoing chemioradiotherapic treatment. We retrospectively reviewed data of severely compromised patients who underwent VAT for lung wedge resections and biopsies carried out in our center over a 7-year period. As far as the area of therapeutic tumor resection is concerned, the present data are consistent with the view that thoracoscopy is both an effective and safe tool in diagnostic procedures. PMID:19811063

  20. From function to esthetics: anterior or occlusal compromises to esthetics.

    PubMed

    Guichet, D L; Guichet, N F

    1993-01-01

    Increased patient expectations together with improved diagnostic, material, and surgical advances have expanded the boundaries of esthetic dentistry. To optimize functional and esthetic success, existing techniques are being enhanced through careful patient selection and management of the occlusion. During the period from 1991 to 1992, several areas relating anterior or occlusal compromises to esthetics have been identified. These include: dental and skeletal malocclusion, periodontal esthetic defects, restorative materials and laboratory techniques, tooth arrangement and maxillomandibular relations, and implant dentistry. This paper reviews some of the literature on these areas during this period. PMID:8401825

  1. Expert review--identification of intra-partum fetal compromise.

    PubMed

    Prior, Tomas; Kumar, Sailesh

    2015-07-01

    Whilst most cases of cerebral palsy occur as a consequence of an ante-natal insult, a significant proportion, particularly in the term fetus, are attributable to intra-partum hypoxia. Intra-partum monitoring using continuous fetal heart rate assessment has led to an increased incidence of operative delivery without a concurrent reduction in the incidence of cerebral palsy. Despite this, birth asphyxia remains the strongest and most consistent risk factor for cerebral palsy in term infants. This review evaluates current intra-partum monitoring techniques as well as alternative approaches aimed at better identification of the fetus at risk of compromise in labour. PMID:25917435

  2. [Frostbite injuries causing compromised airway after inhalation of propane].

    PubMed

    Straarup, Therese Simonsen; Fink, Anders Olsen; Larsen, Jens Kjærgaard Rolighed

    2015-01-01

    We describe a case report of a 23-year-old man with acute pharyngeal injuries due to frostbite subsequent to inhalation of propane. He was fiber-optically intubated on admission to hospital since his airways were considered acutely compromised. He was subsequently kept intubated for 11 days due to persistent pharyngeal oedema and frostbite injuries. The latter is caused by low temperature of propane upon release from a pressurized container. Injuries caused by frostbite often gradually progress and thus caution should be exerted in regards to airway management. PMID:25557449

  3. Anthropogenic noise compromises antipredator behaviour in European eels.

    PubMed

    Simpson, Stephen D; Purser, Julia; Radford, Andrew N

    2015-02-01

    Increases in noise-generating human activities since the Industrial Revolution have changed the acoustic landscape of many terrestrial and aquatic ecosystems. Anthropogenic noise is now recognized as a major pollutant of international concern, and recent studies have demonstrated impacts on, for instance, hearing thresholds, communication, movement and foraging in a range of species. However, consequences for survival and reproductive success are difficult to ascertain. Using a series of laboratory-based experiments and an open-water test with the same methodology, we show that acoustic disturbance can compromise antipredator behaviour--which directly affects survival likelihood--and explore potential underlying mechanisms. Juvenile European eels (Anguilla anguilla) exposed to additional noise (playback of recordings of ships passing through harbours), rather than control conditions (playback of recordings from the same harbours without ships), performed less well in two simulated predation paradigms. Eels were 50% less likely and 25% slower to startle to an 'ambush predator' and were caught more than twice as quickly by a 'pursuit predator'. Furthermore, eels experiencing additional noise had diminished spatial performance and elevated ventilation and metabolic rates (indicators of stress) compared with control individuals. Our results suggest that acoustic disturbance could have important physiological and behavioural impacts on animals, compromising life-or-death responses. PMID:25098970

  4. Progress in Pain Assessment: The Cognitively Compromised Patient

    PubMed Central

    Chapman, C. Richard

    2009-01-01

    Purpose of review Pain assessment is essential for patient care in many settings, but it proves difficult when the patient is cognitively compromised or otherwise unable to produce a conventional pain report. This review describes progress in pain assessment technology that involves the coding of human facial expression. Recent findings It is possible to quantify facial expression by coding patterns of facial muscle contraction and relaxation. These patterns are action units, and they can gauge the intensity of pain as well as signal its occurrence. The experience of pain seems to generate a unique facial expression comprising several action units. Concerns have existed about whether demented patients produce diagnostically meaningful facial expressions of pain because they tend to generate more non-specific facial expressions and perhaps code pain intensity less well than normals. Recent work shows that facial expression reflects pain as well or better in demented patients compared to normals. Summary Although still nascent, coded facial expression appears to work reliably as a pain assessment tool with cognitively compromised patients. Clinical application awaits the development of technology that can automate facial coding and scoring. PMID:18784487

  5. 7 CFR 3550.253 - Settlement of a debt by compromise or adjustment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Settlement of a debt by compromise or adjustment. 3550.253 Section 3550.253 Agriculture Regulations of the Department of Agriculture (Continued) RURAL... Actions § 3550.253 Settlement of a debt by compromise or adjustment. Compromise or adjustment offers...

  6. 7 CFR 3550.253 - Settlement of a debt by compromise or adjustment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 15 2011-01-01 2011-01-01 false Settlement of a debt by compromise or adjustment. 3550.253 Section 3550.253 Agriculture Regulations of the Department of Agriculture (Continued) RURAL... Actions § 3550.253 Settlement of a debt by compromise or adjustment. Compromise or adjustment offers...

  7. 40 CFR 1620.6 - Authority to adjust, determine, compromise, and settle.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., compromise, and settle. 1620.6 Section 1620.6 Protection of Environment CHEMICAL SAFETY AND HAZARD..., determine, compromise, and settle. The General Counsel of CSB, or his or her designee, is delegated authority to consider, ascertain, adjust, determine, compromise and settle claims under the provision of...

  8. 40 CFR 1620.6 - Authority to adjust, determine, compromise, and settle.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., compromise, and settle. 1620.6 Section 1620.6 Protection of Environment CHEMICAL SAFETY AND HAZARD..., determine, compromise, and settle. The General Counsel of CSB, or his or her designee, is delegated authority to consider, ascertain, adjust, determine, compromise and settle claims under the provision of...

  9. Compromises along the Way: Balancing Speed To Market with Sustainability while Delivering Knowledge Management Services.

    ERIC Educational Resources Information Center

    Heyman, Martha K.

    This paper will discuss some of the compromises, and the path to those compromises, that must be made while implementing a successful knowledge management program within a for-profit enterprise. Specifically the following compromises are addressed: (1) manage knowledge where it is created, but do that within a global system; (2) no single scope…

  10. Perceived Career Compromise, Affect and Work-Related Satisfaction in College Students

    ERIC Educational Resources Information Center

    Tsaousides, Theodore; Jome, LaRae

    2008-01-01

    The objective of this study was to investigate the effects of career compromise on positive affect (PA), negative affect (NA), and work-related satisfaction (WRS). Career compromise refers to the modification of occupational preferences under pressing external circumstances [Gottfredson, L. S. (1981). Circumscription and compromise: A…

  11. Protecting Privacy of Shared Epidemiologic Data without Compromising Analysis Potential

    DOE PAGESBeta

    Cologne, John; Grant, Eric J.; Nakashima, Eiji; Chen, Yun; Funamoto, Sachiyo; Katayama, Hiroaki

    2012-01-01

    Objective . Ensuring privacy of research subjects when epidemiologic data are shared with outside collaborators involves masking (modifying) the data, but overmasking can compromise utility (analysis potential). Methods of statistical disclosure control for protecting privacy may be impractical for individual researchers involved in small-scale collaborations. Methods . We investigated a simple approach based on measures of disclosure risk and analytical utility that are straightforward for epidemiologic researchers to derive. The method is illustrated using data from the Japanese Atomic-bomb Survivor population. Results . Masking by modest rounding did not adequately enhance security but rounding to remove several digits ofmore » relative accuracy effectively reduced the risk of identification without substantially reducing utility. Grouping or adding random noise led to noticeable bias. Conclusions . When sharing epidemiologic data, it is recommended that masking be performed using rounding. Specific treatment should be determined separately in individual situations after consideration of the disclosure risks and analysis needs.« less

  12. Enhanced susceptibility to predation in corals of compromised condition

    PubMed Central

    Cameron, Caitlin M.; Miller, Margaret W.

    2015-01-01

    The marine gastropod, Coralliophila abbreviata, is an obligate corallivore that causes substantial mortality in Caribbean Acropora spp. Considering the imperiled status of Acropora cervicornis and A. palmata, a better understanding of ecological interactions resulting in tissue loss may enable more effective conservation strategies. We examined differences in susceptibility of A. cervicornis to C. abbreviata predation based on coral tissue condition. Coral tissue condition was a strong determinant of snail prey choice, with snails preferring A. cervicornis fragments that were diseased or mechanically damaged over healthy fragments. In addition, snails always chose fragments undergoing active predation by another snail, while showing no preference for a non-feeding snail when compared with an undisturbed prey fragment. These results indicate that the condition of A. cervicornis prey influenced foraging behavior of C. abbreviata, creating a potential feedback that may exacerbate damage from predation in coral populations compromised by other types of disturbance. PMID:26734500

  13. Thiamine absorption is not compromised in folate-deficient rats

    SciTech Connect

    Walzem, R.L.; Clifford, A.J.

    1988-11-01

    Thiamine absorption and excretion were assessed in rats with severe folate deficiency (FD) by determining the fate of oral TH-labeled and intravenous UC-labeled thiamine over a 6-h test period. Thiamine status was evaluated in these same rats by measuring transketolase activity levels of blood before (TKA) and after (TPPE) addition of thiamine pyrophosphate to the incubation mixture of the assay procedure. Two additional experiments assessed active transport of thiamine and the effect of dietary succinylsulfathiazole (SST) on TKA and TPPE in rats with moderate FD. Intestinal absorption in general and thiamine absorption in particular and thiamine status were unaltered in rats with severe FD. Inanition associated with severe FD may impair thiamine status. Thiamine absorption by active transport was not compromised in FD, and dietary succinylsulfathiazole did not affect thiamine status.

  14. Suppression of Mic60 compromises mitochondrial transcription and oxidative phosphorylation

    PubMed Central

    Yang, Rui-Feng; Sun, Li-Hong; Zhang, Ran; Zhang, Yuan; Luo, Yu-Xuan; Zheng, Wei; Zhang, Zhu-Qin; Chen, Hou-Zao; Liu, De-Pei

    2015-01-01

    Precise regulation of mtDNA transcription and oxidative phosphorylation (OXPHOS) is crucial for human health. As a component of mitochondrial contact site and cristae organizing system (MICOS), Mic60 plays a central role in mitochondrial morphology. However, it remains unclear whether Mic60 affects mitochondrial transcription. Here, we report that Mic60 interacts with mitochondrial transcription factors TFAM and TFB2M. Furthermore, we found that Mic60 knockdown compromises mitochondrial transcription and OXPHOS activities. Importantly, Mic60 deficiency decreased TFAM binding and mitochondrial RNA polymerase (POLRMT) recruitment to the mtDNA promoters. In addition, through mtDNA immunoprecipitation (mIP)-chromatin conformation capture (3C) assays, we found that Mic60 interacted with mtDNA and was involved in the architecture of mtDNA D-loop region. Taken together, our findings reveal a previously unrecognized important role of Mic60 in mtDNA transcription. PMID:25612828

  15. Protecting Privacy of Shared Epidemiologic Data without Compromising Analysis Potential

    PubMed Central

    Cologne, John; Grant, Eric J.; Nakashima, Eiji; Chen, Yun; Funamoto, Sachiyo; Katayama, Hiroaki

    2012-01-01

    Objective. Ensuring privacy of research subjects when epidemiologic data are shared with outside collaborators involves masking (modifying) the data, but overmasking can compromise utility (analysis potential). Methods of statistical disclosure control for protecting privacy may be impractical for individual researchers involved in small-scale collaborations. Methods. We investigated a simple approach based on measures of disclosure risk and analytical utility that are straightforward for epidemiologic researchers to derive. The method is illustrated using data from the Japanese Atomic-bomb Survivor population. Results. Masking by modest rounding did not adequately enhance security but rounding to remove several digits of relative accuracy effectively reduced the risk of identification without substantially reducing utility. Grouping or adding random noise led to noticeable bias. Conclusions. When sharing epidemiologic data, it is recommended that masking be performed using rounding. Specific treatment should be determined separately in individual situations after consideration of the disclosure risks and analysis needs. PMID:22505949

  16. Conflict and Compromise: Catholic and Public Hospital Partnerships

    PubMed Central

    Wall, Barbra Mann

    2010-01-01

    This article analyzes the tensions and uneasy negotiations, based on a case study, that occurred among Catholic sisters, administrators, bishops, physicians, and the Vatican for more than seven years at a hospital in Austin, Texas. Here, the largest health care system in the city, which was Catholic, joined with the local public, tax-supported hospital that provided the majority of reproductive health care services in the region. A clash resulted over whether the hospital could continue providing sterilization and contraceptive services to its primarily poor patients. This article examines the fierce debates that occurred, especially over emergency contraception and attempts to develop creative solutions after a hierarchical crackdown from the Vatican. The end result was a compromise that included the creation of a “hospital within a hospital.” PMID:20067093

  17. Glycan Side Reaction May Compromise ETD-Based Glycopeptide Identification

    NASA Astrophysics Data System (ADS)

    Darula, Zsuzsanna; Medzihradszky, Katalin F.

    2014-06-01

    Tris(hydroxymethyl)aminomethane (Tris) is one of the most frequently used buffer ingredients. Among other things, it is recommended and is usually used for lectin-based affinity enrichment of glycopeptides. Here we report that sialic acid, a common `capping' unit in both N- and O-linked glycans may react with this chemical, and this side reaction may compromise glycopeptide identification when ETD spectra are the only MS/MS data used in the database search. We show that the modification may alter N- as well as O-linked glycans, the Tris-derivative is still prone to fragmentation both in `beam-type' CID (HCD) and ETD experiments, at the same time—since the acidic carboxyl group was `neutralized'—it will display a different retention time than its unmodified counterpart. We also suggest solutions that—when incorporated into existing search engines—may significantly improve the reliability of glycopeptide assignments.

  18. Mitigating Reptile Road Mortality: Fence Failures Compromise Ecopassage Effectiveness

    PubMed Central

    Baxter-Gilbert, James H.; Riley, Julia L.; Lesbarrères, David; Litzgus, Jacqueline D.

    2015-01-01

    Roadways pose serious threats to animal populations. The installation of roadway mitigation measures is becoming increasingly common, yet studies that rigorously evaluate the effectiveness of these conservation tools remain rare. A highway expansion project in Ontario, Canada included exclusion fencing and ecopassages as mitigation measures designed to offset detrimental effects to one of the most imperial groups of vertebrates, reptiles. Taking a multispecies approach, we used a Before-After-Control-Impact study design to compare reptile abundance on the highway before and after mitigation at an Impact site and a Control site from 1 May to 31 August in 2012 and 2013. During this time, radio telemetry, wildlife cameras, and an automated PIT-tag reading system were used to monitor reptile movements and use of ecopassages. Additionally, a willingness to utilize experiment was conducted to quantify turtle behavioral responses to ecopassages. We found no difference in abundance of turtles on the road between the un-mitigated and mitigated highways, and an increase in the percentage of both snakes and turtles detected dead on the road post-mitigation, suggesting that the fencing was not effective. Although ecopassages were used by reptiles, the number of crossings through ecopassages was lower than road-surface crossings. Furthermore, turtle willingness to use ecopassages was lower than that reported in previous arena studies, suggesting that effectiveness of ecopassages may be compromised when alternative crossing options are available (e.g., through holes in exclusion structures). Our rigorous evaluation of reptile roadway mitigation demonstrated that when exclusion structures fail, the effectiveness of population connectivity structures is compromised. Our project emphasizes the need to design mitigation measures with the biology and behavior of the target species in mind, to implement mitigation designs in a rigorous fashion, and quantitatively evaluate road

  19. Methamphetamine compromises gap junctional communication in astrocytes and neurons.

    PubMed

    Castellano, Paul; Nwagbo, Chisom; Martinez, Luis R; Eugenin, Eliseo A

    2016-05-01

    Methamphetamine (meth) is a central nervous system (CNS) stimulant that results in psychological and physical dependency. The long-term effects of meth within the CNS include neuronal plasticity changes, blood-brain barrier compromise, inflammation, electrical dysfunction, neuronal/glial toxicity, and an increased risk to infectious diseases including HIV. Most of the reported meth effects in the CNS are related to dysregulation of chemical synapses by altering the release and uptake of neurotransmitters, especially dopamine, norepinephrine, and epinephrine. However, little is known about the effects of meth on connexin (Cx) containing channels, such as gap junctions (GJ) and hemichannels (HC). We examined the effects of meth on Cx expression, function, and its role in NeuroAIDS. We found that meth altered Cx expression and localization, decreased GJ communication between neurons and astrocytes, and induced the opening of Cx43/Cx36 HC. Furthermore, we found that these changes in GJ and HC induced by meth treatment were mediated by activation of dopamine receptors, suggesting that dysregulation of dopamine signaling induced by meth is essential for GJ and HC compromise. Meth-induced changes in GJ and HC contributed to amplified CNS toxicity by dysregulating glutamate metabolism and increasing the susceptibility of neurons and astrocytes to bystander apoptosis induced by HIV. Together, our results indicate that connexin containing channels, GJ and HC, are essential in the pathogenesis of meth and increase the sensitivity of the CNS to HIV CNS disease. Methamphetamine (meth) is an extremely addictive central nervous system stimulant. Meth reduced gap junctional (GJ) communication by inducing internalization of connexin-43 (Cx43) in astrocytes and reducing expression of Cx36 in neurons by a mechanism involving activation of dopamine receptors (see cartoon). Meth-induced changes in Cx containing channels increased extracellular levels of glutamate and resulted in higher

  20. Blood–Retinal Barrier Compromise and Endogenous Staphylococcus aureus Endophthalmitis

    PubMed Central

    Coburn, Phillip S.; Wiskur, Brandt J.; Astley, Roger A.; Callegan, Michelle C.

    2015-01-01

    Purpose To test the hypothesis that blood–retinal barrier compromise is associated with the development of endogenous Staphylococcus aureus endophthalmitis. Methods To compromise the blood–retinal barrier in vivo, streptozotocin-induced diabetes was induced in C57BL/6J mice for 1, 3, or 5 months. Diabetic and age-matched nondiabetic mice were intravenously injected with 108 colony-forming units (cfu) of S. aureus, a common cause of endogenous endophthalmitis in diabetics. After 4 days post infection, electroretinography, histology, and bacterial counts were performed. Staphylococcus aureus–induced alterations in in vitro retinal pigment epithelial (RPE) cell barrier structure and function were assessed by anti–ZO-1 immunohistochemistry, FITC-dextran conjugate diffusion, and bacterial transmigration assays. Results We observed one bilateral infection in a control, nondiabetic animal (mean = 1.54 × 103 ± 1.78 × 102 cfu/eye, 7% incidence). Among the 1-month diabetic mice, we observed culture-confirmed unilateral infections in two animals (mean = 5.54 × 102 ± 7.09 × 102 cfu/eye, 12% incidence). Among the 3-month diabetic mice, infections were observed in 11 animals, three with bilateral infections (mean = 2.67 × 102 ± 2.49 × 102 cfu/eye, 58% incidence). Among the 5-month diabetic mice, we observed infections in five animals (mean = 7.88 × 102 ± 1.08 × 103 cfu/eye, 33% incidence). In vitro, S. aureus infection reduced ZO-1 immunostaining and disrupted the barrier function of cultured RPE cells, resulting in diffusion of fluorophore-conjugated dextrans and transmigration of live bacteria across a permeabilized RPE barrier. Conclusions Taken together, these results indicated that S. aureus is capable of inducing blood–retinal barrier permeability and causing endogenous bacterial endophthalmitis in normal and diabetic animals. PMID:26559476

  1. PAB is an assembly chaperone that functions downstream of chaperonin 60 in the assembly of chloroplast ATP synthase coupling factor 1

    PubMed Central

    Mao, Juan; Chi, Wei; Ouyang, Min; He, Baoye; Chen, Fan; Zhang, Lixin

    2015-01-01

    The chloroplast ATP synthase, a multisubunit complex in the thylakoid membrane, catalyzes the light-driven synthesis of ATP, thereby supplying the energy for carbon fixation during photosynthesis. The chloroplast ATP synthase is composed of both nucleus- and chloroplast-encoded proteins that have required the evolution of novel mechanisms to coordinate the biosynthesis and assembly of chloroplast ATP synthase subunits temporally and spatially. Here we have elucidated the assembly mechanism of the α3β3γ core complex of the chloroplast ATP synthase by identification and functional characterization of a key assembly factor, PAB (PROTEIN IN CHLOROPLAST ATPASE BIOGENESIS). PAB directly interacts with the nucleus-encoded γ subunit and functions downstream of chaperonin 60 (Cpn60)-mediated CF1γ subunit folding to promote its assembly into the catalytic core. PAB does not have any recognizable motifs or domains but is conserved in photosynthetic eukaryotes. It is likely that PAB evolved together with the transfer of chloroplast genes into the nucleus to assist nucleus-encoded CF1γ assembly into the CF1 core. Such coordination might represent an evolutionarily conserved mechanism for folding and assembly of nucleus-encoded proteins to ensure proper assembly of multiprotein photosynthetic complexes. PMID:25775508

  2. Complete cDNA and deduced amino acid sequence of the chaperonin containing T-complex polypeptide 1 (CCT) delta subunit from Aedes triseriatus mosquitoes.

    PubMed

    Blitvich, B J; Rayms-Keller, A; Blair, C D; Beaty, B J

    2001-01-01

    The chaperonin containing t-complex polypeptide 1 (CCT) assists in the ATP-dependent folding and assembly of newly translated actin and tubulin in the eukaryotic cytosol. CCT is composed of eight different subunits, each encoded by an independent gene. In this report, we used RT-PCR amplification and 5'- and 3'-rapid amplification of cDNA ends (RACE) to determine the complete cDNA sequence of the CCT delta subunit from Aedes triseriatus mosquitoes. The CCT delta cDNA is 1936 nucleotides in length and encodes a putative 533 amino acid protein with a calculated molecular mass of 57,179 daltons and pI of 7.15. Hydrophobic residues comprise 39.8% of the amino acid sequence and putative motifs for ATP-binding and ATPase-activity are present. The amino acid sequence displays strong sequence similarity to Drosophila melanogaster (92%), human (85%), puffer fish (84%) and mouse (84%) counterparts. CCT delta mRNA was detected in both biosynthetically active (embryonating) and dormant (diapausing) Ae. triseriatus embryos by RT-PCR analysis. PMID:11762197

  3. Supramolecular Nanotube of Chaperonin GroEL: Length Control for Cellular Uptake Using Single-Ring GroEL Mutant as End-Capper.

    PubMed

    Sim, Seunghyun; Niwa, Tatsuya; Taguchi, Hideki; Aida, Takuzo

    2016-09-01

    How to modulate supramolecular protein nanotubes without sacrificing their thermodynamic stability? This challenging issue emerged with an enhanced reality since our successful development of a protein nanotube of chaperonin GroELMC as a novel ATP-responsive 1D nanocarrier because the nanotube length may potentially affect the cellular uptake efficiency. Herein, we report a molecularly engineered protein end-capper (SRMC) that firmly binds to the nanotube termini since the end-capper originates from GroEL. According to the single-ring mutation of GroEL, we obtained a single-ring version of GroEL bearing cysteine mutations (GroELCys) and modified its 14 apical cysteine residues with merocyanine (MC). Whereas SRMC self-dimerizes upon treatment with Mg(2+), we confirmed that SRMC serves as the efficient end-capper for the Mg(2+)-mediated supramolecular polymerization of GroELMC and allows for modulating the average nanotube length over a wide range from 320 to 40 nm by increasing the feed molar ratio SRMC/GroELMC up to 5.4. We also found that the nanotubes shorter than 100 nm are efficiently taken up into HEP3B cells. PMID:27545864

  4. Characterization of a natural mouse monoclonal antibody recognizing epitopes shared by oxidized low-density lipoprotein and chaperonin 60 of Aggregatibacter actinomycetemcomitans.

    PubMed

    Wang, Chunguang; Kankaanpää, Jari; Kummu, Outi; Turunen, S Pauliina; Akhi, Ramin; Bergmann, Ulrich; Pussinen, Pirkko; Remes, Anne M; Hörkkö, Sohvi

    2016-06-01

    Natural antibodies are predominantly antibodies of the IgM isotype present in the circulation of all vertebrates that have not been previously exposed to exogenous antigens. They are often directed against highly conserved epitopes and bind to ligands of varying chemical composition with low affinity. In this study we cloned and characterized a natural mouse monoclonal IgM antibody selected by binding to malondialdehyde acetaldehyde epitopes on low-density lipoprotein (LDL). Interestingly, the IgM antibody cross-reacted with Aggregatibacter actinomycetemcomitans (Aa) bacteria, a key pathogenic microbe in periodontitis reported to be associated with risk factor for atherosclerosis, thus being named as Aa_Mab. It is more intriguing that the binding molecule of Aa to Aa_Mab IgM was found to be Aa chaperonin 60 or HSP60, a member of heat-shock protein family, behaving not only as a chaperone for correct protein folding but also as a powerful virulence factor of the bacteria for inducing bone resorption and as a putative pathogenic factor in atherosclerosis. The findings will highlight the question of whether molecular mimicry between pathogen components and oxidized LDL could lead to atheroprotective immune activity, and also would be of great importance in potential application of immune response-based preventive and therapeutic strategies against atherosclerosis and periodontal disease. PMID:26786003

  5. A proteomic approach to understand MMP-3-driven developmental processes in the postnatal cerebellum: Chaperonin CCT6A and MAP kinase as contributing factors.

    PubMed

    Van Hove, Inge; Verslegers, Mieke; Hu, Tjing-Tjing; Carden, Martin; Arckens, Lutgarde; Moons, Lieve

    2015-09-01

    Matrix metalloproteinase-3 (MMP-3) deficiency in mice was previously reported to result in a transiently retarded granule cell migration at postnatal day 8 (P8) and a sustained disturbed arborization of Purkinje cell dendrites from P8 on, concomitant with a delayed synapse formation between granule cells and Purkinje cells and resulting in mild deficits in motor performance in adult animals. However, the molecular mechanisms by which MMP-3 contributes to proper development of the cerebellar cortex during the first postnatal weeks remains unknown. In this study, we used a functional proteomics approach to investigate alterations in protein expression in postnatal cerebella of wild-type versus MMP-3 deficient mice, and to further elucidate MMP-3-dependent pathways and downstream targets in vivo. At P8, two-dimensional difference gel electrophoresis and mass spectrometry identified 20 unique proteins with a different expression between the two genotypes. Subsequent "Ingenuity Pathway Analysis" and Western blotting indicate that the chaperonin containing T-complex polypeptide 1, subunit 6A and the MAP kinase signaling pathway play a key role in the MMP-3-dependent regulation of neurite outgrowth and neuronal migration in the developing brain. PMID:25652596

  6. Programmed Cell Death Protein 5 Interacts with the Cytosolic Chaperonin Containing Tailless Complex Polypeptide 1 (CCT) to Regulate β-Tubulin Folding* ♦

    PubMed Central

    Tracy, Christopher M.; Gray, Amy J.; Cuéllar, Jorge; Shaw, Tanner S.; Howlett, Alyson C.; Taylor, Ryan M.; Prince, John T.; Ahn, Natalie G.; Valpuesta, José M.; Willardson, Barry M.

    2014-01-01

    Programmed cell death protein 5 (PDCD5) has been proposed to act as a pro-apoptotic factor and tumor suppressor. However, the mechanisms underlying its apoptotic function are largely unknown. A proteomics search for binding partners of phosducin-like protein, a co-chaperone for the cytosolic chaperonin containing tailless complex polypeptide 1 (CCT), revealed a robust interaction between PDCD5 and CCT. PDCD5 formed a complex with CCT and β-tubulin, a key CCT-folding substrate, and specifically inhibited β-tubulin folding. Cryo-electron microscopy studies of the PDCD5·CCT complex suggested a possible mechanism of inhibition of β-tubulin folding. PDCD5 bound the apical domain of the CCTβ subunit, projecting above the folding cavity without entering it. Like PDCD5, β-tubulin also interacts with the CCTβ apical domain, but a second site is found at the sensor loop deep within the folding cavity. These orientations of PDCD5 and β-tubulin suggest that PDCD5 sterically interferes with β-tubulin binding to the CCTβ apical domain and inhibits β-tubulin folding. Given the importance of tubulins in cell division and proliferation, PDCD5 might exert its apoptotic function at least in part through inhibition of β-tubulin folding. PMID:24375412

  7. Protection characteristics of a Faraday cage compromised by lightning burnthrough.

    SciTech Connect

    Warne, Larry Kevin; Bystrom, Edward; Jorgenson, Roy Eberhardt; Montoya, Sandra L.; Merewether, Kimball O.; Coats, Rebecca Sue; Martinez, Leonard E.; Jojola, John M.

    2012-01-01

    A lightning flash consists of multiple, high-amplitude but short duration return strokes. Between the return strokes is a lower amplitude, continuing current which flows for longer duration. If the walls of a Faraday cage are made of thin enough metal, the continuing current can melt a hole through the metal in a process called burnthrough. A subsequent return stroke can couple energy through this newly-formed hole. This LDRD is a study of the protection provided by a Faraday cage when it has been compromised by burnthrough. We initially repeated some previous experiments and expanded on them in terms of scope and diagnostics to form a knowledge baseline of the coupling phenomena. We then used a combination of experiment, analysis and numerical modeling to study four coupling mechanisms: indirect electric field coupling, indirect magnetic field coupling, conduction through plasma and breakdown through the hole. We discovered voltages higher than those encountered in the previous set of experiments (on the order of several hundreds of volts).

  8. Contribution of consultants to care of compromised pregnancies.

    PubMed Central

    Bird, J. S.; Taslimi, M. M.; Gonzales, A. R.; Duggan, M.

    1996-01-01

    Obstetricians often seek consultative services of other specialists in the management of compromised pregnancies. However, the extent of such consultations and the contribution of these consultants have not been addressed in the literature. This study is addresses the contribution of consultants to the care of complicated pregnancies at a tertiary care center. During the 2 1/2 years of this retrospective study, 2263 antepartum admissions were made for pregnancy complications. One hundred sixty-six of those patients were hospitalized 176 times and were treated by one or more consulting physicians for a consultation rate of 7.8%. Eighteen specialties were consulted, including 54 (32%) consultations from maternal fetal medicine, 44 (24%) from internal medicine, 28 (16%) from general surgery, and 22 (12%) from endocrinology. Of the initial admission diagnoses, 87.9% were confirmed and 46 new diagnoses were made by the consultants. A significant positive correlation was noted between the number of consultants, maternal length of hospital stay, and maternal hospitalization cost. PMID:8776065

  9. Compromised central tolerance of ICA69 induces multiple organ autoimmunity

    PubMed Central

    Fan, Yong; Gualtierotti, Giulio; Tajima, Asako; Grupillo, Maria; Coppola, Antonina; He, Jing; Bertera, Suzanne; Owens, Gregory; Pietropaolo, Massimo; Rudert, William A.; Trucco, Massimo

    2015-01-01

    For reasons not fully understood, patients with an organ-specific autoimmune disease have increased risks of developing autoimmune responses against other organs/tissues. We identified ICA69, a known β-cell autoantigen in Type 1 diabetes, as a potential common target in multi-organ autoimmunity. NOD mice immunized with ICA69 polypeptides exhibited exacerbated inflammation not only in the islets, but also in the salivary glands. To further investigate ICA69 autoimmunity, two genetically modified mouse lines were generated to modulate thymic ICA69 expression: the heterozygous ICA69del/wt line and the thymic medullary epithelial cell-specific deletion Aire-ΔICA69 line. Suboptimal central negative selection of ICA69-reactive T-cells was observed in both lines. Aire-ΔICA69 mice spontaneously developed coincident autoimmune responses to the pancreas, the salivary glands, the thyroid, and the stomach. Our findings establish a direct link between compromised thymic ICA69 expression and autoimmunity against multiple ICA69-expressing organs, and identify a potential novel mechanism for the development of multi-organ autoimmune diseases. PMID:25088457

  10. Physiologic assessment of fetal compromise: biomarkers of toxic exposure

    SciTech Connect

    Longo, L.D.

    1987-10-01

    Understanding the physiologic and endocrinologic basis of fetal development is a major goal of perinatal biology. During the past decade a number of technological developments have allowed more precise evaluation of the fetus in utero and diagnosis of abnormalities. Despite these methodological achievements, however, there are no specific biological markers currently available to indicate that exposure to a given xenobiotic is associated with a cellular, subcellular, or pharmacodynamic event. This paper evaluates the following issues: what are some of the unique physiologic and endocrinologic features of the fetal milieu interieur. What problems are peculiar to fetal assessment. What are some examples of validated biomarkers and their applicability. What promising biomarkers are on the horizon. How may molecular probes be of value as biological markers of fetal compromise. What are some of the major research gaps and needs, and how should research priorities be set. Some of these topics are addressed. Moreover, the more general role(s) that various diagnostic methods and biological markers can have in an understanding of the regulation of fetal growth and differentiation and the role of xenobiotics in affecting the normal course of events are discussed.

  11. Risk Factors for Uteroplacental Vascular Compromise and Inflammation

    PubMed Central

    BAKER, Arthur M.; BRAUN, Joe M.; SALAFIA, Carolyn M.; HERRING, Amy H.; DANIELS, Julie; RANKINS, Nicole; THORP, John M.

    2008-01-01

    Objective To identify potentially modifiable risk factors of placental injury reflecting maternal uteroplacental vascular compromise (UPVC) and acute and chronic placental inflammation. Study design A prospective epidemiologic study was conducted. A total of 1270 placentas were characterized by gross and microscopic examination. Placental pathology was coded for features of amniotic fluid infection syndrome (AFIS), chronic villitis, UPVC, and fetal vascular obstructive lesions. Odds ratios between UPVC, the acute and the chronic inflammatory lesions, and risk factors of interest were calculated. Results After adjusting for confounders, women with a history of preterm birth had 1.60 times the odds of chronic inflammation (95% CI: 1.10, 2.55). Women with a previous elective termination had 3.28 times the odds of acute inflammation (95% CI: 1.89, 5.70). The odds of chronic villitis increased with parity, while the odds of AFIS decreased with parity. Conclusion We have identified several predictors of UPVC, AFIS and chronic villitis. Further studies are needed to examine whether interventions to alter UPVC, AFIS and chronic villitis will lead to improved pregnancy outcomes. PMID:18771974

  12. Towards understanding the biological function of the unusual chaperonin Cpn60.1 (GroEL1) of Mycobacterium tuberculosis.

    PubMed

    Sharma, Aditi; Rustad, Tige; Mahajan, Gaurang; Kumar, Arun; Rao, Kanury V S; Banerjee, Sharmistha; Sherman, David R; Mande, Shekhar C

    2016-03-01

    The 60 kDa heat shock proteins, also known as Cpn60s (GroELs) are components of the essential protein folding machinery of the cell, but are also dominant antigens in many infectious diseases. Although generally essential for cellular survival, in some organisms such as Mycobacterium tuberculosis, one or more paralogous Cpn60s are known to be dispensable. In M. tuberculosis, Cpn60.2 (GroEL2) is essential for cell survival, but the biological role of the non-essential Cpn60.1 (GroEL1) is still elusive. To understand the relevance of Cpn60.1 (GroEL1) in M. tuberculosis physiology, detailed transcriptomic analyses for the wild type H37Rv and cpn60.1 knockout (groEL1-KO) were performed under in vitro stress conditions: stationary phase, cold shock, low aeration, mild cold shock and low pH. Additionally, the survival of the groEL1-KO was assessed in macrophages at multiplicity of infection (MOI) of 1:1 and 1:5. We observed that survival under low aeration was significantly compromised in the groEL1-KO. Further, the gene expression analyses under low aeration showed change in expression of several key virulence factors like two component system PhoP/R and MprA/B, sigma factors SigM and C and adversely affected known hypoxia response regulators Rv0081, Rv0023 and DosR. Our work is therefore suggestive of an important role of Cpn60.1 (GroEL1) for survival under low aeration by affecting the expression of genes known for hypoxia response. PMID:26822628

  13. Experimental nonalcoholic steatohepatitis compromises ureagenesis, an essential hepatic metabolic function.

    PubMed

    Thomsen, Karen Louise; Grønbæk, Henning; Glavind, Emilie; Hebbard, Lionel; Jessen, Niels; Clouston, Andrew; George, Jacob; Vilstrup, Hendrik

    2014-08-01

    Nonalcoholic steatohepatitis (NASH) is increasing in prevalence, yet its consequences for liver function are unknown. We studied ureagenesis, an essential metabolic liver function of importance for whole body nitrogen homeostasis, in a rodent model of diet-induced NASH. Rats were fed a high-fat, high-cholesterol diet for 4 and 16 wk, resulting in early and advanced experimental NASH, respectively. We examined the urea cycle enzyme mRNAs in liver tissue, the hepatocyte urea cycle enzyme proteins, and the in vivo capacity of urea-nitrogen synthesis (CUNS). Early NASH decreased all of the urea cycle mRNAs to an average of 60% and the ornithine transcarbamylase protein to 10%, whereas the CUNS remained unchanged. Advanced NASH further decreased the carbamoyl phosphate synthetase protein to 63% and, in addition, decreased the CUNS by 20% [from 5.65 ± 0.23 to 4.58 ± 0.30 μmol × (min × 100 g)(-1); P = 0.01]. Early NASH compromised the genes and enzyme proteins involved in ureagenesis, whereas advanced NASH resulted in a functional reduction in the capacity for ureagenesis. The pattern of urea cycle perturbations suggests a prevailing mitochondrial impairment by NASH. The decrease in CUNS has consequences for the ability of the body to adjust to changes in the requirements for nitrogen homeostasis e.g., at stressful events. NASH, thus, in terms of metabolic consequences, is not an innocuous lesion, and the manifestations of the damage seem to be a continuum with increasing disease severity. PMID:24924745

  14. Efficacy of New Adhesion Promoters on Compromised Hypocalcified Enamel

    PubMed Central

    Venkata, Kishore Mayakuntla Sai; Aileni, Kaladhar Reddy; Sashidhar, Nagam Reddy

    2015-01-01

    Introduction The amount of technological progress occurred in the last few years has brought an add up to the benefits of bonding in Orthodontics. Research-based findings have constantly led to the development of new materials that are aimed to simplify the clinical procedures like bonding of brackets to compromised enamel surfaces. Hence, the present study is aimed to assess the bond strength of orthodontic brackets on fluorosed enamel using adhesion promoters. Aim To evaluate the shear bond strength (SBS) of orthodontic brackets bonded on fluorosed enamel using conventional Transbond XT and new adhesion promoters such as Enhance LC and All Bond 3. Materials and Methods The study involved 90 non carious, extracted teeth with mild to moderate fluorosis randomly divided into 3 Groups. In Group - I (control group) the teeth were bonded with conventional Transbond XT and cured with LED light. In Group - II Enhance LC was applied to fluorosed enamel before bonding and in Group - III All Bond 3 was used. Shear bond strength was tested by using Universal testing Instron machine. ANOVA and Post-Hoc Tukey’s tests were used to compare shear bond strength. Adhesive remnant on the tooth was assessed and scored using adhesive remnant index (ARI). Results Results showed a reduced SBS values (9.43MPa ±3.03) with conventional Transbond XT on fluorosed enamel. Among the adhesion boosters used Enhance LC illustrated lesser SBS values (12.03 MPa ± 4.42) compared with All Bond 3 (14.38MPa ±4.92). ARI showed bond failure at bracket resin interface in group I & group II and at enamel resin interface in group III although statistically insignificant. Conclusion It was concluded that using adhesion boosters on fluorosed enamel showed higher bond strength compared to the control group. Among the two adhesion promoters used All Bond 3 expressed highest bond strength compared to Enhance LC although statistically insignificant. PMID:26393196

  15. Secretion of salivary statherin is compromised in uncontrolled diabetic patients

    PubMed Central

    Izumi, Masahiro; Zhang, Bin-Xian; Dean, David D.; Lin, Alan L.; Saunders, Michèle J.; Hazuda, Helen P.; Yeh, Chih-Ko

    2015-01-01

    Background Statherin is an important salivary protein for maintaining oral health. The purpose of the current study was to determine if differences in statherin levels exist between diabetic and healthy subjects. Methods A total of 48 diabetic and healthy controls were randomly selected from a community-based database. Diabetic subjects (n = 24) had fasting glucose levels > 180 mg/dL, while controls (n = 24) had levels < 110 mg/dL. Parotid saliva (PS) and sublingual/submandibular saliva (SS) were collected and salivary flow rates determined. Salivary statherin levels were determined by densitometry of Western blots. Blood hemoglobin A1c (HbA1c) and total protein in saliva were also obtained. Results SS, but not PS, salivary flow rate and total protein in diabetics were significantly less than those in healthy controls (p = 0.021 & p < 0.001 respectively). Correlation analysis revealed the existence of a negative correlation between PS statherin levels and HbA1c (p = 0.012) and fasting glucose (p = 0.021) levels, while no such correlation was found for SS statherin levels. When statherin levels were normalized to total salivary protein, the proportion of PS statherin, but not SS statherin, in diabetics was significantly less than that in controls (p = 0.032). In contrast, the amount of statherin secretion in SS, but not PS, was significantly decreased in diabetics compared to controls (p = 0.016). Conclusions and general significance The results show that synthesis and secretion of statherin is reduced in diabetics and this reduction is salivary gland specific. As compromised salivary statherin secretion leads to increased oral health risk, this study indicates that routine oral health assessment of these patients is warranted. PMID:25793156

  16. Compromised GABAergic inhibition contributes to tumor-associated epilepsy.

    PubMed

    MacKenzie, Georgina; O'Toole, Kate K; Moss, Stephen J; Maguire, Jamie

    2016-10-01

    Glioblastoma Multiforme (GBM) is the most common form of primary brain tumor with 30-50% of patients presenting with epilepsy. These tumor-associated seizures are often resistant to traditional antiepileptic drug treatment and persist after tumor resection. This suggests that changes in the peritumoral tissue underpin epileptogenesis. It is known that glioma cells extrude pathological concentrations of glutamate which is thought to play a role in tumor progression and the development of epilepsy. Given that pathological concentrations of glutamate have been shown to dephosphorylate and downregulate the potassium chloride cotransporter KCC2, we hypothesized that glioma-induced alterations in KCC2 in the peritumoral region may play a role in tumor-associated epilepsy. Consistent with this hypothesis, we observe a decrease in total KCC2 expression and a dephosphorylation of KCC2 at residue Ser940 in a glioma model which exhibits hyperexcitability and the development of spontaneous seizures. To determine whether the reduction of KCC2 could potentially contribute to tumor-associated epilepsy, we generated mice with a focal knockdown of KCC2 by injecting AAV2-Cre-GFP into the cortex of floxed KCC2 mice. The AAV2-Cre-mediated knockdown of KCC2 was sufficient to induce the development of spontaneous seizures. Further, blocking NKCC1 with bumetanide to offset the loss of KCC2 reduced the seizure susceptibility in glioma-implanted mice. These findings support a mechanism of tumor-associated epilepsy involving downregulation of KCC2 in the peritumoral region leading to compromised GABAergic inhibition and suggest that modulating chloride homeostasis may be useful for seizure control. PMID:27513374

  17. Epigenetic Dysregulation Observed in Monosomy Blastocysts Further Compromises Developmental Potential

    PubMed Central

    Denomme, Michelle M.; McCallie, Blair R.; Parks, Jason C.; Schoolcraft, William B.; Katz-Jaffe, Mandy G.

    2016-01-01

    Epigenetic mechanisms such as DNA methylation regulate genomic imprinting and account for the distinct non-equivalence of the parental genomes in the embryo. Chromosomal aneuploidy, a major cause of infertility, distorts this highly regulated disparity by the presence or absence of chromosomes. The implantation potential of monosomy embryos is negligible compared to their trisomy counterparts, yet the cause for this is unknown. This study investigated the impact of chromosomal aneuploidy on strict epigenetically regulated domains, specifically imprinting control regions present on aneuploid chromosomes. Donated cryopreserved human IVF blastocysts of transferable quality, including trisomy 15, trisomy 11, monosomy 15, monosomy 11, and donor oocyte control blastocysts were examined individually for DNA methylation profiles by bisulfite mutagenesis and sequencing analysis of two maternally methylated imprinting control regions (ICRs), SNRPN (15q11.2) and KCNQ1OT1 (11p15.5), and one paternally methylated imprinting control region, H19 (11p15.5). Imprinted genes within the regions were also evaluated for transcript abundance by RT-qPCR. Overall, statistically significant hypermethylated and hypomethylated ICRs were found in both the trisomy and monosomy blastocysts compared to controls, restricted only to the chromosome affected by the aneuploidy. Increased expression was observed for maternally-expressed imprinted genes in trisomy blastocysts, while a decreased expression was observed for both maternally- and paternally-expressed imprinted genes in monosomy blastocysts. This epigenetic dysregulation and altered monoallelic expression observed at imprinting control regions in aneuploid IVF embryos supports euploid embryo transfer during infertility treatments, and may specifically highlight an explanation for the compromised implantation potential in monosomy embryos. PMID:27271036

  18. Affinity chromatography of GroEL chaperonin based on denatured proteins: role of electrostatic interactions in regulation of GroEL affinity for protein substrates.

    PubMed

    Marchenko, N Iu; Marchenkov, V V; Kaĭsheva, A L; Kashparov, I A; Kotova, N V; Kaliman, P A; Semisotnov, G V

    2006-12-01

    The chaperonin GroEL of the heat shock protein family from Escherichia coli cells can bind various polypeptides lacking rigid tertiary structure and thus prevent their nonspecific association and provide for acquisition of native conformation. In the present work we studied the interaction of GroEL with six denatured proteins (alpha-lactalbumin, ribonuclease A, egg lysozyme in the presence of dithiothreitol, pepsin, beta-casein, and apocytochrome c) possessing negative or positive total charge at neutral pH values and different in hydrophobicity (affinity for a hydrophobic probe ANS). To prevent the influence of nonspecific association of non-native proteins on their interaction with GroEL and make easier the recording of the complexing, the proteins were covalently attached to BrCN-activated Sepharose. At low ionic strength (lower than 60 mM), tight binding of the negatively charged denatured proteins with GroEL (which is also negatively charged) needed relatively low concentrations (approximately 10 mM) of bivalent cations Mg2+ or Ca2+. At the high ionic strength (approximately 600 mM), a tight complex was produced also in the absence of bivalent cations. In contrast, positively charged denatured proteins tightly interacted with GroEL irrespectively of the presence of bivalent cations and ionic strength of the solution (from 20 to 600 mM). These features of GroEL interaction with positively and negatively charged denatured proteins were confirmed by polarized fluorescence (fluorescence anisotropy). The findings suggest that the affinity of GroEL for denatured proteins can be determined by the balance of hydrophobic and electrostatic interactions. PMID:17223789

  19. High hydrostatic pressure can probe the effects of functionally related ligands on the quaternary structures of the chaperonins GroEL and GroES.

    PubMed

    Panda, M; Ybarra, J; Horowitz, P M

    2001-03-01

    We investigated the effects of high hydrostatic pressure in the range of 1--3 kilobars on tetradecameric GroEL, heptameric GroES, and the GroEL-GroES complex. Unlike GroEL monomers formed by urea dissociation, which can be reassembled back to the tetradecamer, the pressure-dissociated monomers do not reassemble readily. This indicates an alteration of their native structures, an example of conformational drift. Pressure versus time profiles and kinetics of the dissociation of both GroEL and GroES at fixed pressures were monitored by light scattering. Unlike GroEL, GroES monomers do reassociate readily. Reaction conditions were varied by adding ATP, Mg(2+), ADP, AMP-PNP, and KCl. At any individual pressure, the dissociation process is governed by both thermodynamics and kinetics. This leads to the decrease in the yield of monomers at lower pressures. In the presence of Mg(2+) and KCl, GroEL is stable up to 3 kilobars. The presence of either ATP or ADP but not AMP-PNP leads to GroEL dissociation at lower pressures. Interestingly, the GroEL-GroES complex is very stable in the range of 1--2.5 kilobars. However, the addition of ADP destabilizes the complex, which dissociates completely at 1.5 kilobars. The results are rationalized in terms of different degrees of cooperativity between individual monomers and heptameric rings in the GroEL tetradecamer. Such allosteric interactions leading to the alteration of quaternary structure of GroEL in the absence of chemical denaturants are important in understanding the mechanism of chaperonin-assisted protein folding by the GroEL-GroES system. PMID:11085994

  20. 28 CFR Appendix to Subpart Y of... - Redelegations of Authority To Compromise and Close Civil Claims

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Redelegations of Authority To Compromise and Close Civil Claims Appendix to Subpart Y of Part 0 Judicial Administration DEPARTMENT OF JUSTICE ORGANIZATION OF THE DEPARTMENT OF JUSTICE Authority To Compromise and Close Civil Claims and Responsibility for Judgments, Fines, Penalties,...

  1. 31 CFR 29.514 - Requests for waiver and/or compromise.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... standards set forth in the FCCS in 31 CFR part 902. (2) A waiver or compromise decision by the Department... Justice for consideration pursuant to 31 CFR 902.1(b). ... waiver and/or compromise. Individuals who receive a demand letter regarding an overpayment may ask...

  2. 22 CFR 304.7 - Authority to adjust, determine, compromise, and settle claims.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 2 2014-04-01 2014-04-01 false Authority to adjust, determine, compromise, and settle claims. 304.7 Section 304.7 Foreign Relations PEACE CORPS CLAIMS AGAINST GOVERNMENT UNDER FEDERAL TORT CLAIMS ACT Procedures § 304.7 Authority to adjust, determine, compromise, and settle claims....

  3. 22 CFR 304.7 - Authority to adjust, determine, compromise, and settle claims.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 2 2013-04-01 2009-04-01 true Authority to adjust, determine, compromise, and settle claims. 304.7 Section 304.7 Foreign Relations PEACE CORPS CLAIMS AGAINST GOVERNMENT UNDER FEDERAL TORT CLAIMS ACT Procedures § 304.7 Authority to adjust, determine, compromise, and settle claims....

  4. 22 CFR 304.7 - Authority to adjust, determine, compromise, and settle claims.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Authority to adjust, determine, compromise, and settle claims. 304.7 Section 304.7 Foreign Relations PEACE CORPS CLAIMS AGAINST GOVERNMENT UNDER FEDERAL TORT CLAIMS ACT Procedures § 304.7 Authority to adjust, determine, compromise, and settle claims....

  5. 22 CFR 304.7 - Authority to adjust, determine, compromise, and settle claims.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 2 2011-04-01 2009-04-01 true Authority to adjust, determine, compromise, and settle claims. 304.7 Section 304.7 Foreign Relations PEACE CORPS CLAIMS AGAINST GOVERNMENT UNDER FEDERAL TORT CLAIMS ACT Procedures § 304.7 Authority to adjust, determine, compromise, and settle claims....

  6. 13 CFR 108.1710 - SBA authority to collect or compromise its claims.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 13 Business Credit and Assistance 1 2011-01-01 2011-01-01 false SBA authority to collect or compromise its claims. 108.1710 Section 108.1710 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION...) Miscellaneous § 108.1710 SBA authority to collect or compromise its claims. SBA may, upon such conditions...

  7. 13 CFR 107.1710 - SBA authority to collect or compromise its claims.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false SBA authority to collect or compromise its claims. 107.1710 Section 107.1710 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION... § 107.1710 SBA authority to collect or compromise its claims. SBA may, upon such conditions and for...

  8. 13 CFR 107.1710 - SBA authority to collect or compromise its claims.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 13 Business Credit and Assistance 1 2011-01-01 2011-01-01 false SBA authority to collect or compromise its claims. 107.1710 Section 107.1710 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION... § 107.1710 SBA authority to collect or compromise its claims. SBA may, upon such conditions and for...

  9. 13 CFR 108.1710 - SBA authority to collect or compromise its claims.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false SBA authority to collect or compromise its claims. 108.1710 Section 108.1710 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION...) Miscellaneous § 108.1710 SBA authority to collect or compromise its claims. SBA may, upon such conditions...

  10. 32 CFR 2001.48 - Loss, possible compromise or unauthorized disclosure.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Loss, possible compromise or unauthorized disclosure. 2001.48 Section 2001.48 National Defense Other Regulations Relating to National Defense... SECURITY INFORMATION Safeguarding § 2001.48 Loss, possible compromise or unauthorized disclosure....

  11. 28 CFR Appendix to Subpart Y of... - Redelegations of Authority To Compromise and Close Civil Claims

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 1 2013-07-01 2013-07-01 false Redelegations of Authority To Compromise and Close Civil Claims Appendix to Subpart Y of Part 0 Judicial Administration DEPARTMENT OF JUSTICE ORGANIZATION OF THE DEPARTMENT OF JUSTICE Authority To Compromise and Close Civil Claims and Responsibility for Judgments, Fines, Penalties,...

  12. 7 CFR 3.19 - Standards for the compromise of claims.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Standards for the compromise of claims. 3.19 Section 3.19 Agriculture Office of the Secretary of Agriculture DEBT MANAGEMENT Standards for the... follow the standards set forth in 31 CFR part 902 for the compromise of debts pursuant to 31 U.S.C....

  13. 46 CFR 502.604 - Compromise of penalties: Relation to assessment proceedings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 9 2010-10-01 2010-10-01 false Compromise of penalties: Relation to assessment... Civil Penalties § 502.604 Compromise of penalties: Relation to assessment proceedings. (a) Scope. Except... Commission may issue a public notice thereof, the terms and language of which are not subject to...

  14. 5 CFR 177.106 - Authority to adjust, determine, compromise, and settle.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Authority to adjust, determine, compromise, and settle. 177.106 Section 177.106 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ADMINISTRATIVE CLAIMS UNDER THE FEDERAL TORT CLAIMS ACT § 177.106 Authority to adjust, determine, compromise, and settle. (a)...

  15. 13 CFR 107.1710 - SBA authority to collect or compromise its claims.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 13 Business Credit and Assistance 1 2013-01-01 2013-01-01 false SBA authority to collect or compromise its claims. 107.1710 Section 107.1710 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION... § 107.1710 SBA authority to collect or compromise its claims. SBA may, upon such conditions and for...

  16. 13 CFR 108.1710 - SBA authority to collect or compromise its claims.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 13 Business Credit and Assistance 1 2012-01-01 2012-01-01 false SBA authority to collect or compromise its claims. 108.1710 Section 108.1710 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION...) Miscellaneous § 108.1710 SBA authority to collect or compromise its claims. SBA may, upon such conditions...

  17. 13 CFR 107.1710 - SBA authority to collect or compromise its claims.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 13 Business Credit and Assistance 1 2014-01-01 2014-01-01 false SBA authority to collect or compromise its claims. 107.1710 Section 107.1710 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION... § 107.1710 SBA authority to collect or compromise its claims. SBA may, upon such conditions and for...

  18. 13 CFR 108.1710 - SBA authority to collect or compromise its claims.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 13 Business Credit and Assistance 1 2014-01-01 2014-01-01 false SBA authority to collect or compromise its claims. 108.1710 Section 108.1710 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION...) Miscellaneous § 108.1710 SBA authority to collect or compromise its claims. SBA may, upon such conditions...

  19. 13 CFR 107.1710 - SBA authority to collect or compromise its claims.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 13 Business Credit and Assistance 1 2012-01-01 2012-01-01 false SBA authority to collect or compromise its claims. 107.1710 Section 107.1710 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION... § 107.1710 SBA authority to collect or compromise its claims. SBA may, upon such conditions and for...

  20. 7 CFR 3.19 - Standards for the compromise of claims.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... follow the standards set forth in 31 CFR part 902 for the compromise of debts pursuant to 31 U.S.C. 3711... 7 Agriculture 1 2012-01-01 2012-01-01 false Standards for the compromise of claims. 3.19 Section 3.19 Agriculture Office of the Secretary of Agriculture DEBT MANAGEMENT Standards for...

  1. Compromise, Well-Being, and Action Behaviors in Young Adults in Career Transition

    ERIC Educational Resources Information Center

    Creed, Peter A.; Blume, Kellie

    2013-01-01

    The authors surveyed 186 first-year university students and assessed their level of career compromise associated with making the transition to university. Compromise was operationalized as the discrepancy between the job characteristics of ideal and expected occupations. The authors also assessed career well-being (satisfaction, distress), action…

  2. 27 CFR 70.482 - Offers in compromise of liabilities (other than forfeiture) under 26 U.S.C.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 U.S.C. (a) In general. The appropriate TTB officer may compromise any civil or criminal liability... involving such liability to the Department of Justice for prosecution or defense. (For compromise of forfeiture liability, see § 70.484 of this part.) Any such liability may be compromised only upon one or...

  3. Robust Public Key Cryptography — A New Cryptosystem Surviving Private Key Compromise

    NASA Astrophysics Data System (ADS)

    Shaik, Cheman

    A weakness of the present-day public key cryptosystems is that these cryptosystems do not survive private-key compromise attacks resulting from an internal breach of trust. In a competitive business environment, private key compromise is a common incident that voids the strength of public key cryptosystems such as RSA and ECC. Bribing corporate employees to disclose their secret keys and inadvertently disclosing secret information are among a plethora of practical attacks that occur at the implementation level. Once a breach of trust takes place and subsequently the private key is revealed, any public key cryptosystem fails to secure electronic data in Internet communications. The revealed key may be used by an attacker to decipher the intercepted data at an intermediary router. This weakness of public key cryptography calls for an additional security measure that enables encryptions to survive private key compromise attacks.

  4. Compromise Approach-Based Genetic Algorithm for Constrained Multiobjective Portfolio Selection Model

    NASA Astrophysics Data System (ADS)

    Li, Jun

    In this paper, fuzzy set theory is incorporated into a multiobjective portfolio selection model for investors’ taking into three criteria: return, risk and liquidity. The cardinality constraint, the buy-in threshold constraint and the round-lots constraints are considered in the proposed model. To overcome the difficulty of evaluation a large set of efficient solutions and selection of the best one on non-dominated surface, a compromise approach-based genetic algorithm is presented to obtain a compromised solution for the proposed constrained multiobjective portfolio selection model.

  5. 38 CFR 1.955 - Regional office Committees on Waivers and Compromises.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Regional office Committees on Waivers and Compromises. 1.955 Section 1.955 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS GENERAL PROVISIONS Referrals to Gao, Department of Justice, Or Irs §...

  6. 38 CFR 1.955 - Regional office Committees on Waivers and Compromises.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Regional office Committees on Waivers and Compromises. 1.955 Section 1.955 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS GENERAL PROVISIONS Referrals to Gao, Department of Justice, Or Irs §...

  7. Compromise - An effective approach for the hierarchical design of structural systems

    NASA Technical Reports Server (NTRS)

    Shupe, J. A.; Mistree, F.; Sobieszczanski-Sobieski, J.

    1987-01-01

    The use of the compromise decision support problem in hierarchical design of structural systems is described. The mathematical template that supports the underlying precepts of hierarchical design in the context of the decision support problem technique is presented. A structural example that demonstrates the efficacy of the approach is included.

  8. ENDOGENOUS FECAL LOSSES OF CALCIUM COMPROMISE CALCIUM BALANCE IN GIRLS WITH CYSTIC FIBROSIS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bone mineral density is compromised in individuals with cystic fibrosis (CF); calcium (Ca) is the major bone mineral. This study examined the impact of endogenous fecal calcium (Vendo) on calcium balance in girls with CF. Vendo was measured in 12 girls with CF (ages 7-18 y). Volunteers made up tw...

  9. Athletics' Little Sisters. Women's Colleges Face Pressure To Score Higher, but Fear Compromising Their Ideals.

    ERIC Educational Resources Information Center

    Jacobson, Jennifer

    2003-01-01

    Women's colleges, which have generally considered sports an integral part of academic life, now face pressures to compete with coed institutions at which sports have taken on a more competitive attitude. Many fear compromising their ideals if they endeavor to match the athletic programs of other institutions. (SLD)

  10. Interleukin-13 promotes expression of Alix to compromise renal tubular epithelial barrier function.

    PubMed

    Xu, Chen; Sun, Guangdong; Yang, Jie; Sun, Qianmei; Tong, Zhaohui

    2015-05-01

    The epithelial barrier dysfunction plays a critical role in a number of kidney diseases. The mechanism is unclear. Alix is a protein involving in protein degradation in epithelial cells. This study aims to investigate that interleukin (IL)-13 inhibits Alix to compromise the kidney epithelial barrier function. In this study, the murine collecting duct cell line (M-1) was cultured in Transwell inserts to investigate the significance of Alix in compromising the epithelial barrier functions. T cell (Teff cells) proliferation assay was employed to assess the antigenicity of ovalbumin (OVA) that was transported across the M-1 monolayer barrier. The results showed that M-1 cells express Alix. Exposure to interleukin (IL)-13 markedly decreased the expression of Alix in M-1 cells, which compromised the M-1 monolayer barrier functions by showing the increases in the permeability to OVA. Over-expression of Alix abolished the IL-13-induced M-1 monolayer barrier dysfunction. Knockdown of Alix significantly increased M-1 monolayer permeability. The OVA collected from the Transwell basal chambers induced the OVA-specific T cell proliferation. We conclude that IL-13 compromises M-1 epithelial barrier functions via inhibiting Alix expression. PMID:25597757

  11. Is patient confidentiality compromised with the electronic health record?: a position paper.

    PubMed

    Wallace, Ilse M

    2015-02-01

    In order for electronic health records to fulfill their expected benefits, protection of privacy of patient information is key. Lack of trust in confidentiality can lead to reluctance in disclosing all relevant information, which could have grave consequences. This position paper contemplates whether patient confidentiality is compromised by electronic health records. The position that confidentiality is compromised was supported by the four bioethical principles and argued that despite laws and various safeguards to protect patients' confidentiality, numerous data breaches have occurred. The position that confidentiality is not compromised was supported by virtue ethics and a utilitarian viewpoint and argued that safeguards keep information confidential and the public feels relatively safe with the electronic health record. The article concludes with an ethically superior position that confidentiality is compromised with the electronic health record. Although organizational and governmental ways of enhancing the confidentiality of patient information within the electronic health record facilitate confidentiality, the ultimate responsibility of maintaining confidentiality rests with the individual end-users and their ethical code of conduct. The American Nurses Association Code of Ethics for nurses calls for nurses to be watchful with data security in electronic communications. PMID:25532832

  12. 78 FR 72016 - User Fees for Processing Installment Agreements and Offers in Compromise

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-02

    ... processing installment agreements and offers in compromise was published in the Federal Register (78 FR 53702... Appropriations Act (IOAA), which is codified at 31 U.S.C. 9701. Under the IOAA and OMB Circular A-25, 58 FR 38142... into currently-not-collectible (CNC) status rather than enter into an installment agreement....

  13. TEMPORAL ASSOCIATION BETWEEN PULMONARY AND SYSTEMIC EFFECTS OF PARTICULATE MATTER IN HEALTHY AND CARDIOVASCULAR COMPROMISED RATS

    EPA Science Inventory

    Temporal association between pulmonary and systemic effects of particulate matter in healthy and cardiovascular compromised rats

    Urmila P. Kodavanti, Mette C. Schladweiler, Allen D. Ledbetter, Russ Hauser*, David C. Christiani*, John McGee, Judy R. Richards, Daniel L. Co...

  14. Does Low Self-Esteem Predict Health Compromising Behaviours among Adolescents?

    ERIC Educational Resources Information Center

    McGee, Rob; Williams, Sheila

    2000-01-01

    Study examined the predictive association for both global and academic self esteem among students ages 9-13 in a large sample of New Zealanders. Results showed levels of global self esteem significantly predicted adolescent reports of problem eating, suicidal ideation, and multiple compromising behaviors. Implications are discussed for the…

  15. 48 CFR 239.7102-2 - Compromising emanations-TEMPEST or other standard.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...-TEMPEST or other standard. 239.7102-2 Section 239.7102-2 Federal Acquisition Regulations System DEFENSE... INFORMATION TECHNOLOGY Security and Privacy for Computer Systems 239.7102-2 Compromising emanations—TEMPEST or....e., an established National TEMPEST standard (e.g., NACSEM 5100, NACSIM 5100A) or a standard used...

  16. 48 CFR 239.7102-2 - Compromising emanations-TEMPEST or other standard.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false Compromising emanations-TEMPEST or other standard. 239.7102-2 Section 239.7102-2 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE SPECIAL CATEGORIES OF CONTRACTING ACQUISITION OF INFORMATION TECHNOLOGY Security and...

  17. 48 CFR 239.7102-2 - Compromising emanations-TEMPEST or other standard.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false Compromising emanations-TEMPEST or other standard. 239.7102-2 Section 239.7102-2 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE SPECIAL CATEGORIES OF CONTRACTING ACQUISITION OF INFORMATION TECHNOLOGY Security and...

  18. 32 CFR 2001.48 - Loss, possible compromise or unauthorized disclosure.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false Loss, possible compromise or unauthorized disclosure. 2001.48 Section 2001.48 National Defense Other Regulations Relating to National Defense INFORMATION SECURITY OVERSIGHT OFFICE, NATIONAL ARCHIVES AND RECORDS ADMINISTRATION CLASSIFIED...

  19. 20 CFR 725.544 - Collection and compromise of claims for overpayment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Collection and compromise of claims for... OF LABOR FEDERAL COAL MINE HEALTH AND SAFETY ACT OF 1969, AS AMENDED CLAIMS FOR BENEFITS UNDER PART C OF TITLE IV OF THE FEDERAL MINE SAFETY AND HEALTH ACT, AS AMENDED Payment of Benefits...

  20. 20 CFR 725.544 - Collection and compromise of claims for overpayment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Collection and compromise of claims for... LABOR FEDERAL COAL MINE HEALTH AND SAFETY ACT OF 1969, AS AMENDED CLAIMS FOR BENEFITS UNDER PART C OF TITLE IV OF THE FEDERAL MINE SAFETY AND HEALTH ACT, AS AMENDED Payment of Benefits...

  1. 20 CFR 410.565 - Collection and compromise of claims for overpayment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Collection and compromise of claims for overpayment. 410.565 Section 410.565 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL COAL MINE HEALTH AND SAFETY ACT OF 1969, TITLE IV-BLACK LUNG BENEFITS (1969- ) Payment of Benefits §...

  2. Inadequate satellite cell replication compromises muscle regrowth following postnatal nutrient restriction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Perinatal growth impairment permanently compromises skeletal muscle mass. The present study assessed the contribution of muscle satellite cell replicative capacity to this deficit. Mouse dams were fed either a low protein (LP, n=7) or control (C, n=6) diet during lactation. Pups were weaned at 21 d ...

  3. 20 CFR 410.565 - Collection and compromise of claims for overpayment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false Collection and compromise of claims for overpayment. 410.565 Section 410.565 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL COAL MINE HEALTH AND SAFETY ACT OF 1969, TITLE IV-BLACK LUNG BENEFITS (1969- ) Payment of Benefits §...

  4. Happenstance and Compromise: A Gendered Analysis of Students' Computing Degree Course Selection

    ERIC Educational Resources Information Center

    Lang, Catherine

    2010-01-01

    The number of students choosing to study computing at university continues to decline this century, with an even sharper decline in female students. This article presents the results of a series of interviews with university students studying computing courses in Australia that uncovered the influence of happenstance and compromise on course…

  5. 76 FR 17843 - Intent To Compromise Claim Against the District of Columbia Public Schools

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-31

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF EDUCATION Intent To Compromise Claim Against the District of Columbia Public Schools AGENCY: Department of... Columbia Public Schools (DCPS) now pending before the Office of Administrative Law Judges (OALJ), Docket...

  6. Near-infrared spectroscopy provides continuous monitoring of compromised lower extremity perfusion during cardiac surgery.

    PubMed

    Prkic, Ivana; Stuth, Eckehard A E

    2016-06-01

    Near-infrared spectroscopy (NIRS) is more frequently used to monitor regional oxygenation/perfusion of the cerebral and somatorenal vascular bed during congenital heart surgery. However, NIRS probes can be placed elsewhere to assess regional perfusion. We report the intraoperative use of NIRS probes on both calves of an infant to continuously monitor changes in the regional oxygenation/perfusion of a lower extremity whose perfusion was compromised after femoral arterial line placement. The NIRS trend of the compromised limb was compared with the contralateral limb throughout congenital heart surgery including the period on cardiopulmonary bypass (CPB). Our case report illustrates that NIRS technology can be used to monitor ongoing lower extremity vascular compromise during congenital heart surgery when it is not practical to directly access and continuously assess the limb. Transient vascular compromise after invasive femoral arterial line or sheath placement for cardiac catheterization in small infants is not infrequent. NIRS technology in such circumstances may help to decide whether watchful waiting is acceptable or immediate interventions are indicated. Continuous NIRS monitoring showed that limb regional oxygenation remained depressed during CPB but dramatically increased in the post-CPB period. PMID:27185674

  7. Using Emergence Theory-Based Curriculum to Teach Compromise Skills to Students with Autistic Spectrum Disorders

    ERIC Educational Resources Information Center

    Fein, Lance; Jones, Don

    2015-01-01

    This study addresses the compromise skills that are taught to students diagnosed with autistic spectrum disorders (ASD) and related social and communication deficits. A private school in the southeastern United States implemented an emergence theory-based curriculum to address these skills, yet no formal analysis was conducted to determine its…

  8. 32 CFR 310.14 - Notification when information is lost, stolen, or compromised.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... purposes, such as identity theft, fraud, stalking, etc. The personal impact on the affected individual may... the Federal Trade Commission's public Web site on identity theft at http://www.consumer.gov/idtheft... the individual of any loss, theft, or compromise (See also, § 310.50 for reporting of the breach...

  9. 32 CFR 310.14 - Notification when information is lost, stolen, or compromised.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... purposes, such as identity theft, fraud, stalking, etc. The personal impact on the affected individual may... the Federal Trade Commission's public Web site on identity theft at http://www.consumer.gov/idtheft... the individual of any loss, theft, or compromise (See also, § 310.50 for reporting of the breach...

  10. 32 CFR 310.14 - Notification when information is lost, stolen, or compromised.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... purposes, such as identity theft, fraud, stalking, etc. The personal impact on the affected individual may... the Federal Trade Commission's public Web site on identity theft at http://www.consumer.gov/idtheft... the individual of any loss, theft, or compromise (See also, § 310.50 for reporting of the breach...

  11. 32 CFR 310.14 - Notification when information is lost, stolen, or compromised.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 2 2012-07-01 2012-07-01 false Notification when information is lost, stolen, or compromised. 310.14 Section 310.14 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) PRIVACY PROGRAM DOD PRIVACY PROGRAM Systems of Records § 310.14 Notification when information is lost, stolen,...

  12. Career Development Strategies as Moderators between Career Compromise and Career Outcomes in Emerging Adults

    ERIC Educational Resources Information Center

    Creed, Peter A.; Hughes, Trinette

    2013-01-01

    The authors surveyed 130 first-year university students (80% female; mean age 20.5) and assessed (a) the level of career compromise they reported between their ideal and enrolled university programs, (b) their career-related strategies, (c) their perceptions of employability, and (d) their career-related distress. The authors tested a model that…

  13. 78 FR 65932 - User Fees for Processing Installment Agreements and Offers in Compromise; Hearing Cancellation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-04

    ... that appeared in the Federal Register on Friday August 30, 2013 (78 FR 53702) announced that a public... Offers in Compromise; Hearing Cancellation AGENCY: Internal Revenue Service (IRS), Treasury. ACTION... hearing on proposed regulations that amend the provider user fees for installment agreements and offers...

  14. 48 CFR 239.7102-2 - Compromising emanations-TEMPEST or other standard.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...-TEMPEST or other standard. 239.7102-2 Section 239.7102-2 Federal Acquisition Regulations System DEFENSE... INFORMATION TECHNOLOGY Security and Privacy for Computer Systems 239.7102-2 Compromising emanations—TEMPEST or....e., an established National TEMPEST standard (e.g., NACSEM 5100, NACSIM 5100A) or a standard used...

  15. 48 CFR 239.7102-2 - Compromising emanations-TEMPEST or other standard.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...-TEMPEST or other standard. 239.7102-2 Section 239.7102-2 Federal Acquisition Regulations System DEFENSE... INFORMATION TECHNOLOGY Security and Privacy for Computer Systems 239.7102-2 Compromising emanations—TEMPEST or....e., an established National TEMPEST standard (e.g., NACSEM 5100, NACSIM 5100A) or a standard used...

  16. Tragic Choices and Moral Compromise: The Ethics of Allocating Kidneys for Transplantation

    PubMed Central

    Hoffmaster, Barry; Hooker, Cliff

    2013-01-01

    Context For almost a decade, the Kidney Transplantation Committee of the United Network for Organ Sharing has been striving to revise its approach to allocating kidneys from deceased donors for transplantation. Two fundamental values, equality and efficiency, are central to distributing this scarce resource. The prevailing approach gives primacy to equality in the temporal form of first-come, first-served, whereas the motivation for a new approach is to redeem efficiency by increasing the length of survival of transplanted kidneys and their recipients. But decision making about a better way of allocating kidneys flounders because it is constrained by the amorphous notion of “balancing” values. Methods This article develops a more fitting, productive approach to resolving the conflict between equality and efficiency by embedding the notion of compromise in the analysis of a tragic choice provided by Guido Calabresi and Philip Bobbitt. For Calabresi and Bobbitt, the goals of public policy with respect to tragic choices are to limit tragedy and to deal with the irreducible minimum of tragedy in the least offensive way. Satisfying the value of efficiency limits tragedy, and satisfying the value of equality deals with the irreducible minimum of tragedy in the least offensive way. But both values cannot be completely satisfied simultaneously. Compromise is occasioned when not all the several obligations that exist in a situation can be met and when neglecting some obligations entirely in order to fulfill others entirely is improper. Compromise is amalgamated with the notion of a tragic choice and then used to assess proposals for revising the allocation of kidneys considered by the Kidney Transplantation Committee. Findings Compromise takes two forms in allocating kidneys: it occurs within particular approaches to allocating kidneys because neither equality nor efficiency can be fully satisfied, and it occurs over the course of sequential approaches to allocating

  17. Influence of political opposition and compromise on conservation outcomes in the Tongass National Forest, Alaska.

    PubMed

    Beier, Colin M

    2008-12-01

    To understand how a highly contentious policy process influenced a major conservation effort, I examined the origins, compromises, and outcomes of the Alaska National Interest Lands Conservation Act of 1980 (ANILCA) for the Tongass National Forest. Tongass wilderness designation was among the most controversial issues in the ANILCA debate, and it faced strong opposition from influential lawmakers, land managers, and Alaska residents. To investigate the influence of this opposition on Tongass conservation outcomes, I conducted a gap analysis of Tongass reserves and a policy analysis of the ANILCA debate and traced the influence of specific interests through the amendments, negotiations, and resulting compromises needed to enact ANILCA. Overall, I found that Tongass reserves comprise a broadly representative cross-section of ecosystems and species habitats in southeastern Alaska. Redrawn reserve boundaries, industry subsidies, and special access regulations reflected compromises to minimize the impact of wilderness conservation on mining, timber, and local stakeholder interests, respectively. Fragmentation of the Admiralty Island National Monument-the most ecologically valuable and politically controversial reserve-resulted from compromises with Alaskan Native (indigenous peoples of Alaska) corporations and timber interests. Despite language to accommodate "reasonable access" to wilderness reserves, ongoing access limitations highlight the concerns of Alaska residents that opposed ANILCA several decades ago. More broadly, the Tongass case suggests that early and ambitious conservation action may offset strong political opposition; compromises needed to establish key reserves often exacerbate development impacts in unprotected areas; and efforts to minimize social conflicts are needed to safeguard the long-term viability of conservation measures. PMID:18847443

  18. Indirect porcelain veneers in periodontally compromised teeth. The hybrid technique: a case report.

    PubMed

    Garcia-Baeza, David; Saavedra, Carlos; Garcia-Adámez, Ramón

    2015-01-01

    The loss of periodontal structure causes an esthetic problem for many patients, especially when the esthetic zone is compromised. Among the various types of solutions is the use of composite resins. While this procedure is not aggressive towards tooth structure, it does require the clinician to have a precise technique, and demands strict longterm maintenance. 1 Another way of treating the compromised teeth is with porcelain veneers. This procedure is especially difficult, however, if carried out on periodontal teeth, as it requires preparation along the roots. 2 The intention of the hybrid technique described in this article is to combine both of these procedures in order to obtain a less aggressive treatment with precise management of the soft tissue and an adequate esthetic outcome. The hybrid technique consists of enlarging the root portion of the teeth with composite resin to obtain a less aggressive tooth preparation, and thereafter placing porcelain veneers. PMID:26171444

  19. A compromise method to facilitate under-represented minority admissions to medical school.

    PubMed

    Reiter, Harold; Maccoon, Kathryn

    2007-05-01

    Ranked purely on the basis of the available reliable and valid measures, the demographic composition of incoming medical students fails to meet societal concerns regarding under-represented minorities (URM). Admissions offices are squeezed, administratively and legally, between honouring objectively measured individual merit and addressing societal needs. Until more successful recruitment and preparation of URM applicants closes that gap, compromise methods balancing those discordant ideals can be applied. Indeed, as progress over time decreases the relative societal need for affirmative action, compromise methods are mandated by no less a voice than that of the United States Supreme Court. This article proffers one such method, based upon the work of Hofstee, and demonstrates how it can be practically applied to a specific URM challenge. As perspective, past and present philosophical approaches to this discordance are categorized. PMID:17041785

  20. Sterile diets for the immuno-compromised: Is there a need?

    NASA Astrophysics Data System (ADS)

    Butterweck, Joseph S.

    1995-02-01

    There is a general misunderstanding in the radiation processing industry about the use of sterile diets in the medical profession. Sterile diets are used on a limited basis in hospitals that specialize in cancer treatment and organ transplants. These patients are severely immuno-compromised. There are many other patients that are immuno-compromised that do not require sterile diets. These patients may require a diet that is pathogen-free and are aslo "low-microbial diets". Nosocomial infections have become a major issue in US hospitals. The "infection control committee" is the focus group responsible to assure nosocomial infections incidence are below the hospital goals. Application of ionizing radiation to sterilize diets has not been chosen because the product is not available at a reasonable total cost. This paper will discuss the hospitals views.

  1. Tail loss compromises immunity in the many-lined skink, Eutropis multifasciata

    NASA Astrophysics Data System (ADS)

    Kuo, Chi-Chien; Yao, Chiou-Ju; Lin, Te-En; Liu, Hsu-Che; Hsu, Yu-Cheng; Hsieh, Ming-Kun; Huang, Wen-San

    2013-04-01

    Tail autotomy incurs energetic costs, and thus, a trade-off in resource allocation may lead to compromised immunity in lizards. We tested the hypothesis that tailless lizards will favor constitutive innate immunity responses over an energetically costly inflammatory response. The influence of fasting and colorful ornamentation was also investigated. We experimentally induced tail autotomy in the lizard Eutropis multifasciata and found that inflammation was suppressed by tail loss, but not further affected by fasting; the suppressive effect of colorful ornamentation was manifested only in males, but not in females. Constitutive innate immunity was not affected by any of these factors. As expected, only costly inflammation was compromised, and a less expensive constitutive innate immunity might be favored as a competent first-line defense during energetically demanding periods. After considering conventional trade-offs among tail regeneration and reproduction, further extending these studies to incorporate disease risk and how this influences escape responses to predators and future reproduction would make worthwhile studies.

  2. A libertarian perspective on the stem cell debate: compromising the uncompromisible.

    PubMed

    Block, Walter

    2010-08-01

    The present paper attempts to forge a compromise between those who maintain that stem cell research is out-and-out murder of young helpless human beings and those who favor this practice. The compromise is predicated upon the libertarian theory of private property rights. Starting out with the premise that not only the fetus but even the fertilized egg is a human being, with all rights thereto, it offers a competition between those who fertilize eggs for research and those who wish to adopt them. If and only if the former win this competition will they be allowed to use these very young human beings for the purposes they have constructed them. This is justified on grounds of avoiding child abuse. PMID:20624766

  3. The use of bonded partial ceramic restorations to recover heavily compromised teeth.

    PubMed

    Politano, Gianfranco; Fabianelli, Andrea; Papacchini, Federica; Cerutti, Antonio

    2016-01-01

    Restorative procedures are accompanied by a reduction of tooth stability, a decrease of fracture resistance, and an increase in deflection of weakened cusps. The choice between a direct or an indirect restorative technique, mainly in posterior areas, is a challenge, and involves biomechanical, anatomical, functional, esthetic, and financial considerations. In this article, the pros and cons of direct restorations are examined, as well as an analysis of indirect restorations and an overview of dental ceramics. In particular, several clinical uses of lithium disilicate overlays with a circumferential adhesive ferrule effect are proposed: heavily compromised vital teeth with thin walls, cracked teeth, and endodontically treated molars. Clinical procedures are described step by step on the basis of data from scientific literature. In conclusion, the use of lithium disilicate in combination with adhesive technologies can lead to a more conservative, economic, and esthetic approach in the restoration of heavily compromised teeth. PMID:27433548

  4. Early visual deprivation severely compromises the auditory sense of space in congenitally blind children.

    PubMed

    Vercillo, Tiziana; Burr, David; Gori, Monica

    2016-06-01

    A recent study has shown that congenitally blind adults, who have never had visual experience, are impaired on an auditory spatial bisection task (Gori, Sandini, Martinoli, & Burr, 2014). In this study we investigated how thresholds for auditory spatial bisection and auditory discrimination develop with age in sighted and congenitally blind children (9 to 14 years old). Children performed 2 spatial tasks (minimum audible angle and space bisection) and 1 temporal task (temporal bisection). There was no impairment in the temporal task for blind children but, like adults, they showed severely compromised thresholds for spatial bisection. Interestingly, the blind children also showed lower precision in judging minimum audible angle. These results confirm the adult study and go on to suggest that even simpler auditory spatial tasks are compromised in children, and that this capacity recovers over time. (PsycINFO Database Record PMID:27228448

  5. A widely displaced Galeazzi-equivalent lesion with median nerve compromise

    PubMed Central

    Galanopoulos, Ilias; Fogg, Quentin; Ashwood, Neil; Fu, Katherine

    2012-01-01

    We present the case of a 14-year-old boy with a right distal radial fracture accompanied by a severely displaced complete distal ulnar physeal separation and associated median nerve compromise. This injury is known as Galeazzi-equivalent lesion in children and is an extremely rare injury associated with growth arrest. Recognition of the lesion can be difficult but wide displacement may be associated with other significant injuries such as neurovascular compromise. Prompt intervention reversed the neurological symptoms. At 10-month postoperation there was neither growth arrest nor loss of motion. Complete separation of the ulna physis remains often because of soft tissue interposition or capsule problems and prompt reduction is recommended in the literature as a priority. PMID:22907852

  6. Rescue of a periodontally compromised tooth by non-surgical treatment: a case report

    PubMed Central

    2016-01-01

    Purpose This article describes a case of the successful non-surgical management of a periodontally compromised maxillary premolar. Methods A combination therapy, including root planing, occlusal adjustment, and tooth splinting, was applied. Clinical and radiographic examinations were performed during the 16-month follow-up period. Results All periodontal parameters were improved. There were dramatic decreases (3–6 mm) in the probing pocket depth, tooth mobility, and marginal bone loss. Interestingly, gradual resolution of the periapical radiolucency and alveolar bone regeneration were observed in the radiographs, and the periodontal condition was maintained during the follow-up period. Conclusions Within the limits of this study, these results demonstrate the importance of natural tooth preservation through proper periodontal treatment and occlusal adjustment of the periodontally compromised tooth, which is typically targeted for tooth extraction and dental implantation. PMID:27127693

  7. Human Milk for Ill and Medically Compromised Infants: Strategies and Ongoing Innovation.

    PubMed

    DiLauro, Sara; Unger, Sharon; Stone, Debbie; O'Connor, Deborah L

    2016-08-01

    The use of human milk (mother's own milk and/or donor milk) in ill or medically compromised infants frequently requires some adaptation to address medical diagnoses and/or altered nutrition requirements. This tutorial describes the nutrition and immunological benefits of breast milk as well as provides evidence for the use of donor milk when mother's own milk is unavailable. Several strategies used to modify human milk to meet the medical and nutrition needs of an ill or medically compromised infant are reviewed. These strategies include (1) the standard fortification of human milk to support adequate growth, (2) the novel concept of target fortification in preterm infants, (3) instructions on how to alter maternal diet to address cow's milk protein intolerance and/or allergy in breast milk-fed infants, and (4) the removal and modification of the fat in breast milk used in infants diagnosed with chylothorax. PMID:26903304

  8. Corporate corruption of the environment: sustainability as a process of compromise.

    PubMed

    Nyberg, Daniel; Wright, Christopher

    2013-09-01

    A key response to environmental degradation, climate change and declining biodiversity has been the growing adoption of market principles in an effort to better value the social good of nature. Through concepts such as 'natural capitalism' and 'corporate environmentalism', nature is increasingly viewed as a domain of capitalist endeavour. In this article, we use convention theory and a pluralist understanding of social goods to investigate how the social good of the environment is usurped by the alternate social good of the market. Through analysis of interviews with sustainability managers and corporate documentation, we highlight how organizational actors employ compromise to temporally settle disputes between competing claims about environmental activities. Our findings contribute to an understanding of the processes of empirically grounded critique and the under-theorized concept of compromise between social goods. Rather than protecting the environment, the corporate promotion of sustainability facilitates the corruption of the social good of the environment and its conversion into a market commodity. PMID:23998318

  9. Diffuse elevated MIBG activity in the renal parenchyma caused by compromised renal blood flow.

    PubMed

    Liu, Bin; Codreanu, Ion; Yang, Jigang; Servaes, Sabah; Zhuang, Hongming

    2014-11-01

    Increased metaiodobenzylguanidine (MIBG) activity in the kidneys is usually focal and commonly attributed to radioactive urine accumulation in the renal pelvis. Hereby, we present 2 cases of abnormal diffuse MIBG activity in the kidneys caused by compromised renal blood flow. The patterns should be differentiated from physiologic renal MIBG activity, especially when the uptake is relatively symmetric as well as from regional MIBG-avid disease. PMID:24999702

  10. Axillary lymph node tuberculosis masquerading as inflammatory breast carcinoma in an immune-compromised patient.

    PubMed

    Chikkannaiah, Panduranga; Vani, B R; Benachinmardi, Kirtilaxmi; Murthy, V Srinivasa

    2016-02-01

    While tuberculosis is still the leading opportunistic infection among human immunodeficiency virus-seropositive patients, extra-pulmonary tuberculosis is more common than pulmonary tuberculosis, with lymph nodes being a common site. Axillary lymph node pathology such as tuberculosis and lymphoma rarely mimics inflammatory breast carcinoma by producing lymphatic obstruction. We report a case of axillary lymph node tuberculosis in a 40-year-old immune-compromised woman, clinically presenting as inflammatory breast carcinoma. PMID:25681261

  11. Dental implants in bilateral bifid canal and compromised interocclusal space using cone beam computerized tomography

    PubMed Central

    Ahmed, Nizar; Arunachalam, Lalitha Tanjore; Jacob, Caroline Annette; Kumar, Suresh Anand

    2016-01-01

    Knowledge of various anatomic landmarks is pivotal for important success. Bifid canals pose a challenge and can lead to difficulties while performing implant surgery in the mandible. Bifid canals can be diagnosed with panoramic radiography and more accurately with cone beam computerized tomography (CBCT). This case report details the placement of the implant in a patient with bilateral bifid canal and compromised interocclusal space, which was successfully treated using CBCT. PMID:27433073

  12. Immediate Esthetic Rehabilitation of Periodontally Compromised Anterior Tooth Using Natural Tooth as Pontic

    PubMed Central

    Kumar, K. Pavan; Nujella, Surya Kumari; Gopal, S. Sujatha

    2016-01-01

    For patients who require removal of anterior teeth and their replacement various treatment modalities are available. With advancement in technology and availability of glass/polyethylene fibres, use of natural tooth as pontic with fibre reinforced composite restorations offers the promising results. The present case report describes management of periodontally compromised mandibular anterior tooth using natural tooth pontic with fibre reinforcement. A 1-year follow-up showed that the bridge was intact with good esthetics and no problem was reported. PMID:27195156

  13. Dental implants in bilateral bifid canal and compromised interocclusal space using cone beam computerized tomography.

    PubMed

    Ahmed, Nizar; Arunachalam, Lalitha Tanjore; Jacob, Caroline Annette; Kumar, Suresh Anand

    2016-01-01

    Knowledge of various anatomic landmarks is pivotal for important success. Bifid canals pose a challenge and can lead to difficulties while performing implant surgery in the mandible. Bifid canals can be diagnosed with panoramic radiography and more accurately with cone beam computerized tomography (CBCT). This case report details the placement of the implant in a patient with bilateral bifid canal and compromised interocclusal space, which was successfully treated using CBCT. PMID:27433073

  14. Immediate Esthetic Rehabilitation of Periodontally Compromised Anterior Tooth Using Natural Tooth as Pontic.

    PubMed

    Kumar, K Pavan; Nujella, Surya Kumari; Gopal, S Sujatha; Roy, K Karthik

    2016-01-01

    For patients who require removal of anterior teeth and their replacement various treatment modalities are available. With advancement in technology and availability of glass/polyethylene fibres, use of natural tooth as pontic with fibre reinforced composite restorations offers the promising results. The present case report describes management of periodontally compromised mandibular anterior tooth using natural tooth pontic with fibre reinforcement. A 1-year follow-up showed that the bridge was intact with good esthetics and no problem was reported. PMID:27195156

  15. Indications and contraindications of dental implants in medically compromised patients: Update

    PubMed Central

    Gómez-de Diego, Rafael; Mang-de la Rosa, María del Rocío; Romero-Pérez, María J.; Cutando-Soriano, Antonio

    2014-01-01

    The aim of this study was to review the current scientific literature in order to analyse the indications and contraindications of dental implants in medically compromised patients. A reference research was carried out on PubMed using the key words “implant” AND (oral OR dental) AND (systemic disease OR medically compromised), in articles published between 1993 and 2013. The inclusion criteria were the following: clinical studies in which, at least, 10 patients were treated, consensus articles, reviewed articles and meta-analysis performed in humans treated with dental implants, and which included the disease diagnosis. A total of 64 articles were found, from which 16 met the inclusion criteria. Cardiac systemic diseases, diabetic endocrine pathologies or controlled metabolic disorders do not seem to be a total or partial contraindication to the placement of dental implants. Tobacco addiction, and head and neck radiotherapy are correlated to a higher loss of dental implants. Patients suffering from osteoporosis undergoing biphosphonates therapy show an increased risk of developing bone necrosis after an oral surgery, especially if the drugs are administered intravenously or they are associated to certain concomitant medication. Key words:Dental implants, medically compromised patient, systemic diseases. PMID:24608222

  16. Loss of GSNOR1 Function Leads to Compromised Auxin Signaling and Polar Auxin Transport.

    PubMed

    Shi, Ya-Fei; Wang, Da-Li; Wang, Chao; Culler, Angela Hendrickson; Kreiser, Molly A; Suresh, Jayanti; Cohen, Jerry D; Pan, Jianwei; Baker, Barbara; Liu, Jian-Zhong

    2015-09-01

    Cross talk between phytohormones, nitric oxide (NO), and auxin has been implicated in the control of plant growth and development. Two recent reports indicate that NO promoted auxin signaling but inhibited auxin transport probably through S-nitrosylation. However, genetic evidence for the effect of S-nitrosylation on auxin physiology has been lacking. In this study, we used a genetic approach to understand the broader role of S-nitrosylation in auxin physiology in Arabidopsis. We compared auxin signaling and transport in Col-0 and gsnor1-3, a loss-of-function GSNOR1 mutant defective in protein de-nitrosylation. Our results showed that auxin signaling was impaired in the gsnor1-3 mutant as revealed by significantly reduced DR5-GUS/DR5-GFP accumulation and compromised degradation of AXR3NT-GUS, a useful reporter in interrogating auxin-mediated degradation of Aux/IAA by auxin receptors. In addition, polar auxin transport was compromised in gsnor1-3, which was correlated with universally reduced levels of PIN or GFP-PIN proteins in the roots of the mutant in a manner independent of transcription and 26S proteasome degradation. Our results suggest that S-nitrosylation and GSNOR1-mediated de-nitrosylation contribute to auxin physiology, and impaired auxin signaling and compromised auxin transport are responsible for the auxin-related morphological phenotypes displayed by the gsnor1-3 mutant. PMID:25917173

  17. Patterns of health-compromising behaviors among Minnesota adolescents: sociodemographic variations.

    PubMed Central

    Neumark-Sztainer, D; Story, M; French, S; Cassuto, N; Jacobs, D R; Resnick, M D

    1996-01-01

    OBJECTIVES: This study compared prevalence rates of health-compromising behaviors among boys and girls from different ethnic backgrounds in early, middle, and late adolescence and compared co-occurrences of such behaviors across gender and ethnic groups. METHODS: The study population included 123 132 adolescents in grades 6, 9, and 12. Adolescents completed a classroom-administered statewide survey focusing on high-risk behaviors, including unhealthy weight loss, substance abuse, suicide risk, delinquency, and sexual activity. RESULTS: Prevalence rates of most health-compromising behaviors differed by gender, increased with age, and tended to be highest among American Indian youth and lowest among Asian Americans. Strong associations were found between substance abuse and delinquency across all ethnic groups. Substance abuse and delinquency were associated with suicide risk across most ethnic groups. Covariations with sexual activity and unhealthy weight loss behaviors showed more ethnic variation. CONCLUSIONS: Prevention interventions should take into account the tendency for health-compromising behaviors to co-occur and should be sensitive to demographic and socioeconomic differences in behavior patterns. PMID:8916527

  18. Development of an in vitro model for studying the penetration of chemicals through compromised skin.

    PubMed

    Davies, Diane J; Heylings, Jon R; McCarthy, Timothy J; Correa, Catherine M

    2015-02-01

    The conventional safety approach that includes dermal absorption of pharmaceutical or consumer products uses models that are based on intact skin. However, when products are intended for application to skin with a less effective barrier, such as in new-born infants, or in cases where the skin is mildly damaged or diseased, there are instances where absorption through compromised skin is also important. A tape stripping procedure was investigated using dermatomed pig skin to assess if an in vitro model could replicate the typical changes in barrier function observed in humans with compromised skin. The relationship between Trans-Epidermal Water Loss (TEWL), Electrical Resistance (ER) and Tritiated Water Flux(TWF), markers of skin barrier function in OECD 428 studies was investigated. There was a step-wise reduction in ER from normal (control) skin following 5, 10, 15 or 20 tape strips. This was mirrored by increases in both TWF and TEWL. An in vitro experimental protocol using 5 tape strips, ER and dermatomed pig skin provided a rapid, robust and reproducible approach equivalent to the 3–4-fold increases in TEWL observed clinically in compromised skin. PMID:25450748

  19. Deficiencies in mitochondrial DNA compromise the survival of yeast cells at critically high temperatures.

    PubMed

    Zubko, Elena I; Zubko, Mikhajlo K

    2014-01-01

    To address possible roles of mitochondrial genes in adaptation of eukaryotic cells to critical temperatures, we compared thermotolerance of mitochondrial rho mutants and wild type cells of six rho positive yeast species: Candida glabrata, Saccharomyces bayanus, Saccharomyces cerevisiae, Saccharomyces eubayanus, Saccharomyces paradoxus and Saccharomyces pastorianus. All rho mutants manifested compromised thermotolerance as a common phenotype. Analysis of viabilities at critical temperatures (32-45 °C) showed the reduction of maximum permissive temperatures (MPTs) in all rho mutants in comparison to their wild type counterparts. Degrees of the compromised thermotolerance depended on maximum permissive temperatures for wild type cells: the highest levels of MPT reductions for rho mutants took place in species and strains with highest MPTs for wild types. Short term exposures of S. cerevisiae cells (up to 3.5h) at non-permissive temperatures (45 °C and 50 °C) also lead to more rapid cell death of rho mutants as compared to wild type cells. We conclude that: (1) compromised thermotolerance could be a generic phenotypic property of rho mutants; (2) the enhanced thermotolerance of cells possessing mitochondrial genomes could be one of selective advantages in adaptation to environmental factors, in particular to enhanced temperatures. PMID:23890722

  20. Pilot Analysis of Asbestos-induced Diffuse Pleural Thickening with Respiratory Compromise.

    PubMed

    Nojima, Daisuke; Fujimoto, Nobukazu; Kato, Katsuya; Fuchimoto, Yasuko; Kiura, Katsuyuki; Kishimoto, Takumi; Tanimoto, Mitsune

    2015-01-01

    We investigated the clinical features of asbestos-induced diffuse pleural thickening (DPT) with severe respiratory compromise. We conducted a retrospective study of consecutive subjects with asbestos-induced DPT. Medical data such as initial symptoms, radiological findings, respiratory function test results, and clinical course were collected and analyzed. There were 24 patients between 2003 and 2012. All were men, and the median age at the development of DPT was 74 years. The top occupational category associated with asbestos exposure was dockyard workers. The median duration of asbestos exposure was 35.0 years, and the median latency from first exposure to the onset of DPT was 49.0 years. There were no significant differences in respiratory function test results between the higher and lower Brinkman index groups or between unilateral and bilateral DPT. Thirteen patients had a history of benign asbestos pleural effusion (BAPE), and the median duration from pleural fluid accumulation to DPT with severe respiratory compromise was 28.4 months. DPT with severe respiratory compromise can develop after a long latency following occupational asbestos exposure and a history of BAPE. PMID:26490022

  1. Immunological consequences of stress-related proteins--cytosolic tryparedoxin peroxidase and chaperonin TCP20--identified in splenic amastigotes of Leishmania donovani as Th1 stimulatory, in experimental visceral leishmaniasis.

    PubMed

    Jaiswal, Anil Kumar; Khare, Prashant; Joshi, Sumit; Rawat, Keerti; Yadav, Narendra; Sundar, Shyam; Dube, Anuradha

    2015-04-01

    In earlier studies, proteomic characterization of splenic amastigote fractions from clinical isolates of Leishmania donovani, exhibiting significant cellular responses in cured Leishmania subjects, led to the identification of cytosolic tryparedoxin peroxidase (LdcTryP) and chaperonin-TCP20 (LdTCP20) as Th1-stimulatory proteins. Both the proteins, particularly LdTCP20 for the first time, were successfully cloned, overexpressed, purified and were found to be localized in the cytosol of purified splenic amastigotes. When evaluated against lymphocytes of cured Leishmania-infected hamsters, the purified recombinant proteins (rLdcTryP and rLdTCP20) induced their proliferations as well as nitric oxide production. Similarly, these proteins also generated Th1-type cytokines (IFN-γ/IL-12) from stimulated PBMCs of cured/endemic Leishmania patients. Further, vaccination with rLdcTryP elicited noticeable delayed-type hypersensitivity response and offered considerably good prophylactic efficacy (~78% inhibition) against L. donovani challenge in hamsters, which was well supported by the increased mRNA expression of Th1 and Th2 cytokines. However, animals vaccinated with rLdTCP20 exhibited comparatively lesser prophylactic efficacy (~55%) with inferior immunological response. The results indicate the potentiality of rLdcTryP protein, between the two, as a suitable anti-leishmanial vaccine. Since, rLdTCP20 is also an important target, for optimization, further attempts towards determination of immunodominant regions for designing fusion peptides may be taken up. PMID:25498563

  2. Clinical Outcomes of Osseointegrated Prosthetic Auricular Reconstruction in Patients With a Compromised Ipsilateral Temporoparietal Fascial Flap.

    PubMed

    Zuo, Kevin J; Wilkes, Gordon H

    2016-01-01

    Patients with major ear deformities and associated compromise of the superficial temporal artery are poor candidates for autogenous ear reconstruction because of a tenuous ipsilateral temporoparietal fascial flap (TPFF). Osseointegrated prosthetic auricular reconstruction (OPAR) is an alternative to contralateral free TPFF microsurgical and autogenous reconstruction, but data on clinical outcomes are limited. The records of patients with ear loss or major deformity and a compromised ipsilateral TPFF who underwent OPAR from 1989 to 2013 were reviewed. Satisfaction was assessed using a questionnaire based on a 5 point Likert scale. Thirty-two patients (8 women, 24 men) with mean age 43.0 years (range, 10-70 years) underwent OPAR. The ipsilateral TPFF was compromised due to major trauma (13 patients), cancer extirpation (9), burn injury (4), previous harvest (4), arteriovenous malformation (1), or infection (1). All but 2 patients had an associated craniofacial defect, such as soft tissue deformity (87.5%), hearing loss (46.9%), or bony deformity (31.3%). The overall implant success rate was 88.6% at mean follow-up time of 7.6 years post-OPAR. Prosthesis wear averaged 12.2 hours/day and 6.6 days/week (80.5 hours/week). All 5 patients who experienced implant failures had received prior head and neck irradiation. With their prosthesis, 76.2% (16 patients) stated that their self-consciousness and self-esteem were "better" or "much better," whereas 85.7% (18 patients) stated that their self-image was "better" or "much better." All patients declared that they would undergo the treatment again. Osseointegrated prosthetic auricular reconstruction is a reliable option in this challenging population with high patient satisfaction. Patients with prior radiotherapy may have a higher chance of implant failure and would benefit from extended annual follow-up. PMID:26703031

  3. Live Attenuated S. Typhimurium Vaccine with Improved Safety in Immuno-Compromised Mice

    PubMed Central

    Periaswamy, Balamurugan; Maier, Lisa; Vishwakarma, Vikalp; Slack, Emma; Kremer, Marcus; Andrews-Polymenis, Helene L.; McClelland, Michael; Grant, Andrew J.; Suar, Mrutyunjay; Hardt, Wolf-Dietrich

    2012-01-01

    Live attenuated vaccines are of great value for preventing infectious diseases. They represent a delicate compromise between sufficient colonization-mediated adaptive immunity and minimizing the risk for infection by the vaccine strain itself. Immune defects can predispose to vaccine strain infections. It has remained unclear whether vaccine safety could be improved via mutations attenuating a vaccine in immune-deficient individuals without compromising the vaccine's performance in the normal host. We have addressed this hypothesis using a mouse model for Salmonella diarrhea and a live attenuated Salmonella Typhimurium strain (ssaV). Vaccination with this strain elicited protective immunity in wild type mice, but a fatal systemic infection in immune-deficient cybb−/−nos2−/− animals lacking NADPH oxidase and inducible NO synthase. In cybb−/−nos2−/− mice, we analyzed the attenuation of 35 ssaV strains carrying one additional mutation each. One strain, Z234 (ssaV SL1344_3093), was >1000-fold attenuated in cybb−/−nos2−/− mice and ≈100 fold attenuated in tnfr1−/− animals. However, in wt mice, Z234 was as efficient as ssaV with respect to host colonization and the elicitation of a protective, O-antigen specific mucosal secretory IgA (sIgA) response. These data suggest that it is possible to engineer live attenuated vaccines which are specifically attenuated in immuno-compromised hosts. This might help to improve vaccine safety. PMID:23029007

  4. Neogene and Quaternary coexisting in the geological time scale: The inclusive compromise

    NASA Astrophysics Data System (ADS)

    McGowran, Brian; Berggren, Bill; Hilgen, Frits; Steininger, Fritz; Aubry, Marie-Pierre; Lourens, Lucas; Van Couvering, John

    2009-11-01

    Removing the Tertiary and Quaternary Periods whilst conserving the Paleogene and Neogene Periods in The Geological Timescale 2004 caused a storm of protest. One response was to advocate restoring an enlarged Quaternary and consigning the Neogene to a minor role within the Tertiary. Amongst an array of practical, traditional, sentimental and anthropocentric reasons for this response, the one hard-core justification was that the rigidly nested hierarchy of the geological timescale must be preserved. The central objective of this paper is conserving the historically legitimate, Miocene-present, Neogene Period and System. There are two options for conserving the Quaternary concurrently with the Neogene: (i) an inclusive compromise in a flexible hierarchy, and (ii) an upgrading of Pliocene and Pleistocene divisions to the level of epoch. In the inclusive compromise there coexist alternative pathways through the hierarchical ranks. Thus geohistorians and biohistorians have two options for traversing the hierarchy from era to age, as in this example using the hierarchical positioning of the Calabrian Age and Stage: either Cenozoic [era]↔Neogene [period]↔Pleistocene [epoch]↔Calabrian [age], or Cenozoic [era]↔Quaternary [subera]↔Pleistocene [epoch]↔Calabrian [age]. We reaffirm that the inclusive compromise is entirely viable. In so doing we (i) challenge the necessity of the rigidly nested hierarchy, which should be capable of a little flexibility; (ii) reject all analogies of the arbitrary and conventional chronostratigraphic hierarchy with three natural biological hierarchies; (iii) reaffirm the integrity of the Neogene extending to the present; and (iv) see no reason to doubt the harmonious coexistence of the two options preserving the Quaternary and Neogene traditions in an orderly working and stable time scale. In the alternative schema conserving the Neogene, divisions of the Pliocene and Pleistocene are upgraded, so that the Late Pleistocene, Early

  5. Arsenic promotes centrosome abnormalities and cell colony formation in p53 compromised human lung cells

    SciTech Connect

    Liao Weiting; Lin Pinpin; Cheng, T.-S.; Yu, H.-S.; Chang, Louis W.

    2007-12-01

    Epidemiological evidence indicated that residents, especially cigarette smokers, in arseniasis areas had significantly higher lung cancer risk than those living in non-arseniasis areas. Thus, an interaction between arsenic and cigarette smoking in lung carcinogenesis was suspected. p53 dysfunction or mutation in lung epithelial cells was frequently observed in cigarette smokers. Our present study was to explore the differential effects by arsenic on H1355 cells (human lung adenocarcinoma cell line with mutation in p53), BEAS-2B (immortalized lung epithelial cell with functional p53) and pifithrin-{alpha}-treated BEAS-2B cells (p53-inhibited cells). These cells were treated with different doses of sodium arsenite (0, 0.1, 1, 5 and 10 {mu}M) for 48 h. A greater reduction in cell viability was observed in the BEAS-2B cells vs. p53 compromised cells (H1355 or p53-inhibited BEAS-2B). Similar observation was also made on 7-day cell survival (growth) study. TUNEL analysis confirmed that there was indeed a significantly reduced arsenite-induced apoptosis found in p53-compromised cells. Centrosomal abnormality has been attributed to eventual chromosomal missegregation, aneuploidy and tumorigenesis. In our present study, reduced p21 and Gadd45a expressions and increased centrosomal abnormality (atopic and multiple centrosomes) were observed in both arsenite-treated H1355 and p53-inhibited BEAS-2B cells as compared with similarly treated BEAS-2B cells. Increased anchorage-independent growth (colony formation) of BEAS-2B cells co-treated with pifithrin-{alpha} and 5 {mu}M sodium arsenite was also observed in soft agar. Our present investigation demonstrated that arsenic would act specifically on p53 compromised cells (either with p53 dysfunction or inhibited) to induce centrosomal abnormality and colony formation. These findings provided strong evidence on the carcinogenic promotional role of arsenic, especially under the condition of p53 dysfunction.

  6. Risky Driving, Mental Health, and Health-Compromising Behaviors: Risk Clustering in Late Adolescents and Adults

    PubMed Central

    Sommers, Marilyn S.; Fargo, Jamison D.

    2014-01-01

    Background Health-compromising behaviors in adolescents and adults co-occur. Because motor vehicle crashes are the leading cause of death and disability for these age groups, understanding the association between risky driving and other health compromising behaviors is critical. Methods We performed a secondary analysis of data from a randomized controlled trial of an intervention for participants who screened positive for risky driving and problem drinking. Using baseline data, we examined relationships among conduct behavior problems before and after age 15, depressive symptoms, sleep, problem drinking, and risky driving (hostile, reckless and drinking and driving) in late adolescents ages 18–24 (n= 110) and adults ages 25–44 (n= 202). We developed a measurement model for the entire sample using confirmatory factor analysis, which was then specified as a multi-group structural equation model. Results Late adolescents and adults had some similar associations for pathways through problem drinking to drinking and driving; depression to reckless driving; and conduct behavior problems after 15 to hostile driving. Late adolescents, however, had more complex relationships: depressive symptoms and conduct behavior problems before 15 were associated with more risky driving behaviors through multiple pathways and males reported more risky driving. Conclusions Risky driving is associated with other health-compromising behaviors and mental health factors. It is a multidimensional phenomenon more pronounced in late adolescence than adulthood. In order to promote safe driving, the findings support the need to consider behaviors that are a health threat in the late adolescent population during driving training and licensure. PMID:24814717

  7. Compromised Prefrontal Cognitive Control Over Emotional Interference in Adolescents with Internet Gaming Disorder.

    PubMed

    Lee, Junghan; Lee, Seojung; Chun, Ji Won; Cho, Hyun; Kim, Dai-jin; Jung, Young-Chul

    2015-11-01

    Increased reports of impulsivity and aggression in male adolescents with Internet gaming might reflect their dysfunction in emotion regulation, particularly in suppression of negative emotions, which should affect the various stages of Internet gaming disorder. This study tested the hypothesis that adolescents with Internet gaming disorder would be more disturbed by the emotional interference and demonstrate compromised dorsal anterior cingulate cortex (dACC) activation during a Stroop Match-to-Sample task. In addition, functional connectivity analysis was conducted to examine the interplays between neural correlates involved in emotional processing and how they were altered in adolescents with Internet gaming disorder. The Internet gaming disorder group demonstrated weaker dACC activation and stronger insular activations to interfering angry facial stimuli compared with the healthy control group. Negative functional connectivity between stronger insular activation and weaker dorsolateral prefrontal activation correlated with higher cognitive impulsivity in adolescents with Internet gaming disorder. These findings provide evidence of the compromised prefrontal cognitive control over emotional interference in adolescents with Internet gaming disorder. PMID:26430731

  8. Scanning electron microscopic analysis of the effect of Carisolv gel on periodontally compromised human root surfaces.

    PubMed

    Grisi, Daniela Corrêa; Theodoro, Letícia Helena; Sampaio, José Eduardo César; Grisi, Márcio Fernando de Moraes; Salvador, Sérgio Luiz de Souza

    2006-01-01

    The aim of this study was to analyze, under scanning electron microscopy (SEM), the morphologic characteristics of root surfaces after application of Carisolv gel in association with scaling and root planing (SRP). Sixty periodontally compromised extracted human teeth were randomly assigned to 6 groups: 1) SRP alone; 2) passive topical application of Carisolv + SRP; 3) active topical application of Carisolv + SRP; 4) multiple applications of Carisolv + SRP; 5) SRP + 24% EDTA; 6) topical application of Carisolv + SRP + 24% EDTA. Carisolv gel was applied to root surfaces for 30 s, followed by scaling and root planing, consisting of 50 strokes with Gracey curettes in an apical-coronal direction, parallel to the long axis of the tooth. The only exception was group 4, in which the roots were instrumented until a smooth, hard and glass-like surface was achieved. All specimens were further analyzed by SEM. The results showed that the treatment with Carisolv caused significant changes in root surface morphology of periodontally compromised teeth only when the chemical agent was actively applied (burnishing technique). Carisolv failed to remove the smear layer completely, especially with a single application, independently of the method of application. Multiple applications of Carisolv were necessary to achieve a smear layer reduction comparable to that obtained with 24% EDTA conditioning. PMID:16924336

  9. 2-Sulfonylpyrimidines: Mild alkylating agents with anticancer activity toward p53-compromised cells.

    PubMed

    Bauer, Matthias R; Joerger, Andreas C; Fersht, Alan R

    2016-09-01

    The tumor suppressor p53 has the most frequently mutated gene in human cancers. Many of p53's oncogenic mutants are just destabilized and rapidly aggregate, and are targets for stabilization by drugs. We found certain 2-sulfonylpyrimidines, including one named PK11007, to be mild thiol alkylators with anticancer activity in several cell lines, especially those with mutationally compromised p53. PK11007 acted by two routes: p53 dependent and p53 independent. PK11007 stabilized p53 in vitro via selective alkylation of two surface-exposed cysteines without compromising its DNA binding activity. Unstable p53 was reactivated by PK11007 in some cancer cell lines, leading to up-regulation of p53 target genes such as p21 and PUMA. More generally, there was cell death that was independent of p53 but dependent on glutathione depletion and associated with highly elevated levels of reactive oxygen species and induction of endoplasmic reticulum (ER) stress, as also found for the anticancer agent PRIMA-1(MET)(APR-246). PK11007 may be a lead for anticancer drugs that target cells with nonfunctional p53 or impaired reactive oxygen species (ROS) detoxification in a wide variety of mutant p53 cells. PMID:27551077

  10. Pathogen associated molecular pattern (PAMP)-triggered immunity is compromised under C-limited growth.

    PubMed

    Park, Hyeong Cheol; Lee, Shinyoung; Park, Bokyung; Choi, Wonkyun; Kim, Chanmin; Lee, Sanghun; Chung, Woo Sik; Lee, Sang Yeol; Sabir, Jamal; Bressan, Ray A; Bohnert, Hans J; Mengiste, Tesfaye; Yun, Dae-Jin

    2015-01-31

    In the interaction between plants and pathogens, carbon (C) resources provide energy and C skeletons to maintain, among many functions, the plant immune system. However, variations in C availability on pathogen associated molecular pattern (PAMP) triggered immunity (PTI) have not been systematically examined. Here, three types of starch mutants with enhanced susceptibility to Pseudomonas syringae pv. tomato DC3000 hrcC were examined for PTI. In a dark period-dependent manner, the mutants showed compromised induction of a PTI marker, and callose accumulation in response to the bacterial PAMP flagellin, flg22. In combination with weakened PTI responses in wild type by inhibition of the TCA cycle, the experiments determined the necessity of C-derived energy in establishing PTI. Global gene expression analyses identified flg22 responsive genes displaying C supply-dependent patterns. Nutrient recycling-related genes were regulated similarly by C-limitation and flg22, indicating re-arrangements of expression programs to redirect resources that establish or strengthen PTI. Ethylene and NAC transcription factors appear to play roles in these processes. Under C-limitation, PTI appears compromised based on suppression of genes required for continued biosynthetic capacity and defenses through flg22. Our results provide a foundation for the intuitive perception of the interplay between plant nutrition status and pathogen defense. PMID:25387755

  11. Mixed-species Biofilm Compromises Wound Healing by Disrupting Epidermal Barrier Function

    PubMed Central

    Sinha, Mithun; Ganesh, Kasturi; Chaney, Sarah; Mann, Ethan; Miller, Christina; Khanna, Savita; Bergdall, Valerie K.; Powell, Heather M.; Cook, Charles H.; Gordillo, Gayle M.; Wozniak, Daniel J.; Sen, Chandan K.

    2015-01-01

    In chronic wounds, biofilm infects host tissue for extended periods of time. This work establishes the first chronic pre-clinical model of wound biofilm infection aimed at addressing long-term host response. Although biofilm infected wounds did not show marked differences in wound closure, the repaired skin demonstrated compromised barrier function. This observation is clinically significant because it leads to the notion that even if a biofilm infected wound is closed as observed visually, it may be complicated by the presence of failed skin which is likely to be infected and or further complicated post-closure. Study of underlying mechanisms recognized for the first time biofilm-inducible miR-146a and miR-106b in the host skin wound-edge tissue. These miRs silenced ZO-1 and ZO-2 to compromise tight junction function resulting in leaky skin as measured by transepidermal water loss. Intervention strategies aimed at inhibiting biofilm-inducible miRNAs may be productive in restoring barrier function of host skin. PMID:24771509

  12. Metabolic engineering of lipid catabolism increases microalgal lipid accumulation without compromising growth

    PubMed Central

    Trentacoste, Emily M.; Shrestha, Roshan P.; Smith, Sarah R.; Glé, Corine; Hartmann, Aaron C.; Hildebrand, Mark; Gerwick, William H.

    2013-01-01

    Biologically derived fuels are viable alternatives to traditional fossil fuels, and microalgae are a particularly promising source, but improvements are required throughout the production process to increase productivity and reduce cost. Metabolic engineering to increase yields of biofuel-relevant lipids in these organisms without compromising growth is an important aspect of advancing economic feasibility. We report that the targeted knockdown of a multifunctional lipase/phospholipase/acyltransferase increased lipid yields without affecting growth in the diatom Thalassiosira pseudonana. Antisense-expressing knockdown strains 1A6 and 1B1 exhibited wild-type–like growth and increased lipid content under both continuous light and alternating light/dark conditions. Strains 1A6 and 1B1, respectively, contained 2.4- and 3.3-fold higher lipid content than wild-type during exponential growth, and 4.1- and 3.2-fold higher lipid content than wild-type after 40 h of silicon starvation. Analyses of fatty acids, lipid classes, and membrane stability in the transgenic strains suggest a role for this enzyme in membrane lipid turnover and lipid homeostasis. These results demonstrate that targeted metabolic manipulations can be used to increase lipid accumulation in eukaryotic microalgae without compromising growth. PMID:24248374

  13. Evaluation of instant cup noodle, irradiated for immuno-compromised patients

    NASA Astrophysics Data System (ADS)

    Lee, Ji-Hye; Kim, Jae-Kyung; Park, Jae-Nam; Yoon, Young-Min; Sung, Nak-Yun; Kim, Jae-Hun; Song, Beom-Seok; Yook, Hong-Sun; Kim, Byeong-Keun; Lee, Ju-Woon

    2012-08-01

    In the present study, initial microbial load of instant cup noodle (ICN) was investigated and gamma irradiation applied to develop immuno-compromised patients food for their safe consumption. The initial microbial population of dried vegetable and meat, and noodle was below the detection limit (1 log CFU/g); however, that of seasoning powder was just above 4 log CFU/g. Moreover, rehydrated-ICN with water at 100 °C still show above 3 log CFU/g of microbial load, which indicates the need for an additional process to control microbial safety of the seasoning powder. The total aerobic bacteria in seasoning powder and rehydrated-ICN could be controlled with 17 kGy gamma irradiation. This result referred 17 kGy gamma irradiation could reach 'practical sterility' of ICN. The overall difference in sensory properties between the non-irradiated and irradiated ICN was insignificant. Thus, gamma irradiation could improve the microbial quality of ICN, and reduce the risk of infection posed by the seasoning powder, without any adverse effects on their sensory quality. These results suggest that gamma-irradiated ICN can be used as a snack food for immuno-compromised patients.

  14. Hippocampal function is compromised in an animal model of multiple sclerosis.

    PubMed

    Novkovic, T; Shchyglo, O; Gold, R; Manahan-Vaughan, D

    2015-11-19

    Multiple sclerosis (MS) is a progressive inflammatory autoimmune disease that is characterized by demyelination and axonal damage in the nervous system. One obvious consequence is a cumulative loss of muscle control. However, cognitive dysfunction affects roughly half of MS sufferers, sometimes already early in the disease course. Although long-term (remote) memory is typically unaffected, the ability to form new declarative memories becomes compromised. A major structure for the encoding of new declarative memories is the hippocampus. Encoding is believed to be mediated by synaptic plasticity in the form of long-term potentiation (LTP) and long-term depression (LTD) of synaptic strength. Here, in an animal model of MS we explored whether disease symptoms are accompanied by a loss of functional neuronal integrity, synaptic plasticity, or hippocampus-dependent learning ability. In mice that developed MOG35-55-induced experimental autoimmune encephalomyelitis (EAE), passive properties of CA1 pyramidal neurons were unaffected, although the ability to fire action potentials became reduced in the late phase of EAE. LTP remained normal in the early phase of MOG35-55-induced EAE. However, in the late phase, LTP was impaired and LTP-related spatial memory was impaired. In contrast, LTD and hippocampus-dependent object recognition memory were unaffected. These data suggest that in an animal model of MS hippocampal function becomes compromised as the disease progresses. PMID:25795599

  15. Fibre reinforcement in a structurally compromised endodontically treated molar: a case report.

    PubMed

    Soares, Renita; de Ataide, Ida de Noronha; Fernandes, Marina; Lambor, Rajan

    2016-05-01

    The reconstruction of structurally compromised posterior teeth is a rather challenging procedure. The tendency of endodontically treated teeth (ETT) to fracture is considerably higher than vital teeth. Although posts and core build-ups followed by conventional crowns have been generally employed for the purpose of reconstruction, this procedure entails sacrificing a considerable amount of residual sound enamel and dentin. This has drawn the attention of researchers to fibre reinforcement. Fibre-reinforced composite (FRC), designed to replace dentin, enables the biomimetic restoration of teeth. Besides improving the strength of the restoration, the incorporation of glass fibres into composite resins leads to favorable fracture patterns because the fibre layer acts as a stress breaker and stops crack propagation. The following case report presents a technique for reinforcing a badly broken-down ETT with biomimetic materials and FRC. The proper utilization of FRC in structurally compromised teeth can be considered to be an economical and practical measure that may obviate the use of extensive prosthetic treatment. PMID:27200283

  16. Compromised zinc status of experimental rats as a consequence of prolonged iron & calcium supplementation

    PubMed Central

    Jayalakshmi, S.; Platel, Kalpana

    2016-01-01

    Background & objectives: Iron supplementation is usually given to pregnant and lactating women who may also have marginal deficiency of zinc. The negative impact of supplemental iron and calcium on zinc status is a cause of concern. The present investigation was undertaken to examine the effect of inclusion of iron and calcium in the diet at supplementary levels on zinc status of experimental rats. Methods: Groups of experimental rats were maintained on diets supplemented with iron (Molar ratio - Zn:Fe 1:30) and calcium (Molar ratio - Zn:Ca 1:667) both individually and in combination for six weeks. Zinc status of these rats was assessed by determining zinc concentration in circulation and in organs, and the activities of zinc containing enzymes in serum and liver. Results: The zinc status of experimental rats receiving supplemental levels of iron and calcium was significantly compromised. Zinc concentration in serum, kidney, spleen and liver was reduced significantly by both these minerals. Six weeks of supplementation of iron and calcium individually, significantly reduced the activity of liver and serum superoxide dismutase and alkaline phosphatase. Activity of liver alcohol dehydrogenase was lowered in calcium supplemented group and in calcium + iron supplemented group, while that of carbonic anhydrase was significantly reduced by iron, calcium and their combination. Interpretation & conclusions: Supplemental levels of iron and calcium, both individually and in combination, significantly compromised the zinc status of experimental rats. This negative effect of these two minerals was more prominent when these were supplemented for a period of six weeks. PMID:27121523

  17. Can Neglected Tropical Diseases Compromise Human Wellbeing in Sex-, Age-, and Trait-Specific Ways?

    PubMed Central

    Geary, David C.

    2016-01-01

    Traits that facilitate competition for reproductive resources or that influence mate choice have evolved to signal resilience to infectious disease and other stressors. As a result, the dynamics of competition and choice can, in theory, be used to generate predictions about sex-, age-, and trait-specific vulnerabilities for any sexually reproducing species, including humans. These dynamics and associated vulnerabilities are reviewed for nonhuman species, focusing on traits that are compromised by exposure to parasites. Using the same approach, sex-, age-, and trait-specific vulnerabilities to parasitic disease are illustrated for children’s and adolescent’s physical growth and fitness. Suggestions are then provided for widening the assessment of human vulnerabilities to include age-appropriate measures of behavioral (e.g., children’s play) and cognitive (e.g., language fluency) traits. These are traits that are likely to be compromised by infection in age- and sex-specific ways. Inclusion of these types of measures in studies of neglected tropic diseases has the potential to provide a more nuanced understanding of how these diseases undermine human wellbeing and may provide a useful means to study the efficacy of associated treatments. PMID:27077746

  18. Fibre reinforcement in a structurally compromised endodontically treated molar: a case report

    PubMed Central

    de Ataide, Ida de Noronha; Fernandes, Marina; Lambor, Rajan

    2016-01-01

    The reconstruction of structurally compromised posterior teeth is a rather challenging procedure. The tendency of endodontically treated teeth (ETT) to fracture is considerably higher than vital teeth. Although posts and core build-ups followed by conventional crowns have been generally employed for the purpose of reconstruction, this procedure entails sacrificing a considerable amount of residual sound enamel and dentin. This has drawn the attention of researchers to fibre reinforcement. Fibre-reinforced composite (FRC), designed to replace dentin, enables the biomimetic restoration of teeth. Besides improving the strength of the restoration, the incorporation of glass fibres into composite resins leads to favorable fracture patterns because the fibre layer acts as a stress breaker and stops crack propagation. The following case report presents a technique for reinforcing a badly broken-down ETT with biomimetic materials and FRC. The proper utilization of FRC in structurally compromised teeth can be considered to be an economical and practical measure that may obviate the use of extensive prosthetic treatment. PMID:27200283

  19. Designing and Operating Through Compromise: Architectural Analysis of CKMS for the Advanced Metering Infrastructure

    SciTech Connect

    Duren, Mike; Aldridge, Hal; Abercrombie, Robert K; Sheldon, Frederick T

    2013-01-01

    Compromises attributable to the Advanced Persistent Threat (APT) highlight the necessity for constant vigilance. The APT provides a new perspective on security metrics (e.g., statistics based cyber security) and quantitative risk assessments. We consider design principals and models/tools that provide high assurance for energy delivery systems (EDS) operations regardless of the state of compromise. Cryptographic keys must be securely exchanged, then held and protected on either end of a communications link. This is challenging for a utility with numerous substations that must secure the intelligent electronic devices (IEDs) that may comprise complex control system of systems. For example, distribution and management of keys among the millions of intelligent meters within the Advanced Metering Infrastructure (AMI) is being implemented as part of the National Smart Grid initiative. Without a means for a secure cryptographic key management system (CKMS) no cryptographic solution can be widely deployed to protect the EDS infrastructure from cyber-attack. We consider 1) how security modeling is applied to key management and cyber security concerns on a continuous basis from design through operation, 2) how trusted models and key management architectures greatly impact failure scenarios, and 3) how hardware-enabled trust is a critical element to detecting, surviving, and recovering from attack.

  20. 42 CFR 405.376 - Suspension and termination of collection action and compromise of claims for overpayment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CFR 404.515. (b) Definitions. As used in this section, debtor means a provider of services or a... necessary evidence, and related pragmatic considerations, for compromise under paragraph (d)(3) of...

  1. 42 CFR 405.376 - Suspension and termination of collection action and compromise of claims for overpayment.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... CFR 404.515. (b) Definitions. As used in this section, debtor means a provider of services or a... necessary evidence, and related pragmatic considerations, for compromise under paragraph (d)(3) of...

  2. Immediate implants and immediate loading in periodontally compromised patients-a 3-year prospective clinical study.

    PubMed

    Alves, Celia Coutinho; Correia, Andre Ricardo; Neves, Manuel

    2010-10-01

    To avoid the necessity of a removable provisional prosthesis, and therefore preserve the patient's functional outcome, esthetics, and quality of life, a clinical protocol was developed to approach periodontally compromised patients presenting a full-arch irreversibly lost dentition: full-arch extraction and immediate replacement with a provisional acrylic resin implant-supported fixed partial denture (FPD). A total of 23 periodontally compromised patients (11 women, 12 men; 4 smokers, 4 controlled diabetics) were included in this study. Pretreatment casts were taken and vertical dimension of occlusion was determined. In most patients, 6 Straumann implants were distributed along the arch according to the surgical guide or bone availability, with the most distal ones in the maxilla slightly tilted so they could emerge more distally. A total of 168 implants (146 Straumann, 10 Nobel Biocare, 8 Biomet 3i, and 4 Lifecore) were placed (83 in the maxilla, 85 in the mandible). Of those in the maxilla, 74 were loaded immediately (implant stability quotient mentor [ISQm] > 70) and 9 placed with delayed loading (ISQm =/< 70). Of the 85 implants placed in the mandible, all were loaded immediately (ISQm > 70). If an FPD had not been fabricated already, impressions were taken during surgery to do so. The prosthesis was then adapted (cemented or screwed) to the 6 implants within the first 48 hours postsurgery. After 2 months, definitive impressions were taken, and a definitive porcelain-fused-to-metal implant-supported 12-element FPD was fabricated and cemented or screwed to all 6 implants. Of the 168 implants, 108 were immediate implants and 159 immediately loaded. Only 2 implants (1 in the mandible, 1 in the maxilla) did not osseointegrate. This yields a 3-year cumulative survival rate of 98.74% (98.65% in the maxilla, 98.82% in the mandible). From a total of 26 immediately loaded prostheses (12 in the maxilla, 14 in the mandible), 6 were cemented and 20 screw-retained. The 3

  3. Cytokines and olfactory bulb microglia in response to bacterial challenge in the compromised primary olfactory pathway

    PubMed Central

    2012-01-01

    Background The primary olfactory pathway is a potential route through which microorganisms from the periphery could potentially access the central nervous system. Our previous studies demonstrated that if the olfactory epithelium was damaged, bacteria administered into the nasal cavity induced nitric oxide production in olfactory ensheathing cells. This study investigates the cytokine profile of olfactory tissues as a consequence of bacterial challenge and establishes whether or not the bacteria are able to reach the olfactory bulb in the central nervous system. Methods The olfactory epithelium of C57BL/6 mice was damaged by unilateral Triton X-100 nasal washing, and Staphylococcus aureus was administered ipsilaterally 4 days later. Olfactory mucosa and bulb were harvested 6 h, 24 h and 5 days after inoculation and their cytokine profile compared to control tissues. The fate of S. aureus and the response of bulbar microglia were examined using fluorescence microscopy and transmission electron microscopy. Results In the olfactory mucosa, administered S. aureus was present in supporting cells of the olfactory epithelium, and macrophages and olfactory nerve bundles in the lamina propria. Fluorescein isothiocyanate-conjugated S. aureus was observed within the olfactory mucosa and bulb 6 h after inoculation, but remained restricted to the peripheral layers up to 5 days later. At the 24-h time point, the level of interleukin-6 (IL-6) and tumour necrosis factor-α in the compromised olfactory tissues challenged with bacteria (12,466 ± 956 pg/ml and 552 ± 193 pg/ml, respectively) was significantly higher than that in compromised olfactory tissues alone (6,092 ± 1,403 pg/ml and 80 ± 2 pg/ml, respectively). Immunohistochemistry confirmed that IL-6 was present in several cell types including olfactory ensheathing cells and mitral cells of the olfactory bulb. Concurrently, there was a 4.4-, 4.5- and 2.8-fold increase in the density of i

  4. 46 CFR Appendix A to Subpart W of... - Example of Compromise Agreement To Be Used Under 46 CFR 502.604

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 9 2011-10-01 2011-10-01 false Example of Compromise Agreement To Be Used Under 46 CFR 502.604 A Appendix A to Subpart W of Part 502 Shipping FEDERAL MARITIME COMMISSION GENERAL AND... Compromise Agreement To Be Used Under 46 CFR 502.604 Compromise Agreement FMC File No. ____ This Agreement...

  5. 46 CFR Appendix A to Subpart W of... - Example of Compromise Agreement To Be Used Under 46 CFR 502.604

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 9 2014-10-01 2014-10-01 false Example of Compromise Agreement To Be Used Under 46 CFR 502.604 A Appendix A to Subpart W of Part 502 Shipping FEDERAL MARITIME COMMISSION GENERAL AND... Compromise Agreement To Be Used Under 46 CFR 502.604 Compromise Agreement FMC File No. ____ This Agreement...

  6. 46 CFR Appendix A to Subpart W of... - Example of Compromise Agreement To Be Used Under 46 CFR 502.604

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 9 2010-10-01 2010-10-01 false Example of Compromise Agreement To Be Used Under 46 CFR 502.604 A Appendix A to Subpart W of Part 502 Shipping FEDERAL MARITIME COMMISSION GENERAL AND... Compromise Agreement To Be Used Under 46 CFR 502.604 Compromise Agreement FMC File No. ____ This Agreement...

  7. 46 CFR Appendix A to Subpart W of... - Example of Compromise Agreement To Be Used Under 46 CFR 502.604

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 9 2013-10-01 2013-10-01 false Example of Compromise Agreement To Be Used Under 46 CFR 502.604 A Appendix A to Subpart W of Part 502 Shipping FEDERAL MARITIME COMMISSION GENERAL AND... Compromise Agreement To Be Used Under 46 CFR 502.604 Compromise Agreement FMC File No. ____ This Agreement...

  8. 46 CFR Appendix A to Subpart W of... - Example of Compromise Agreement To Be Used Under 46 CFR 502.604

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 9 2012-10-01 2012-10-01 false Example of Compromise Agreement To Be Used Under 46 CFR 502.604 A Appendix A to Subpart W of Part 502 Shipping FEDERAL MARITIME COMMISSION GENERAL AND... Compromise Agreement To Be Used Under 46 CFR 502.604 Compromise Agreement FMC File No. ____ This Agreement...

  9. Impaired blood supply in the colonic anastomosis in mice compromises healing.

    PubMed

    Pommergaard, Hans-Christian; Achiam, Michael Patrick; Burcharth, Jakob; Rosenberg, Jacob

    2015-01-01

    Colon anastomotic leakage has a multifactorial etiology and ischemia is considered one of the most important single factors. However, no existing animal models have established a direct link between ischemia and anastomotic leakage. The aim of this study was to establish a model of colon anastomotic leakage as a result of tissue ischemia. In colon anastomoses of 53 C57BL/6 mice, varying degrees of ischemia were induced. Supplying vessels were divided with bipolar coagulation in order to reduce anastomotic breaking strength and create clinical anastomotic leakage. Breaking strength of all the ischemic anastomoses were significantly lower compared with controls. Increasing ischemia resulted in higher rates of large bowel obstruction without creating anastomotic leakage. Healing was compromised as a result of impaired blood supply. However, clinical leakage was absent. Pure ischemia in otherwise healthy experimental animals may be too simple of an approach to create clinical leakage. PMID:25594642

  10. Failing to forget: inhibitory-control deficits compromise memory suppression in posttraumatic stress disorder.

    PubMed

    Catarino, Ana; Küpper, Charlotte S; Werner-Seidler, Aliza; Dalgleish, Tim; Anderson, Michael C

    2015-05-01

    Most people have experienced distressing events that they would rather forget. Although memories of such events become less intrusive with time for the majority of people, those with posttraumatic stress disorder (PTSD) are afflicted by vivid, recurrent memories of their trauma. Often triggered by reminders in the daily environment, these memories can cause severe distress and impairment. We propose that difficulties with intrusive memories in PTSD arise in part from a deficit in engaging inhibitory control to suppress episodic retrieval. We tested this hypothesis by adapting the think/no-think paradigm to investigate voluntary memory suppression of aversive scenes cued by naturalistic reminders. Retrieval suppression was compromised significantly in PTSD patients, compared with trauma-exposed control participants. Furthermore, patients with the largest deficits in suppression-induced forgetting were also those with the most severe PTSD symptoms. These results raise the possibility that prefrontal mechanisms supporting inhibitory control over memory are impaired in PTSD. PMID:25847536

  11. Giant Prolactinoma Presenting with Neck Pain and Structural Compromise of the Occipital Condyles.

    PubMed

    Yecies, Derek; Ajlan, Abdulrazag; Ratliff, John; Ziskin, Jennifer; Hwang, Peter; Vogel, Hannes; Katznelson, Laurence; Harsh, Griffith

    2015-11-01

    Prolactinomas are the most common form of endocrinologically active pituitary adenoma; they account for ∼ 45% of pituitary adenomas encountered in clinical practice. Giant adenomas are those > 4 cm in diameter. Less than 0.5% of pituitary adenomas encountered in neurosurgical practice are giant prolactinomas. Patients with giant prolactinomas typically present with highly elevated prolactin levels, endocrinologic disturbances, and neurologic symptoms from mass-induced pressure. Described here is an unusual case of a giant prolactinoma presenting with neck pain and structural compromise of the occipital condyles. Transnasal biopsy of the nasopharyngeal portion of the mass obtained tissue consistent with an atypical prolactinoma with p53 reactivity and a high Ki-67 index of 5%. Despite the size and invasiveness of the tumor, the patient had resolution of his clinical symptoms, dramatic reduction of his hyperprolactinemia, and near-complete disappearance of his tumor following medical treatment. PMID:26623246

  12. Giant Prolactinoma Presenting with Neck Pain and Structural Compromise of the Occipital Condyles

    PubMed Central

    Yecies, Derek; Ajlan, Abdulrazag; Ratliff, John; Ziskin, Jennifer; Hwang, Peter; Vogel, Hannes; Katznelson, Laurence; Harsh, Griffith

    2015-01-01

    Prolactinomas are the most common form of endocrinologically active pituitary adenoma; they account for ∼ 45% of pituitary adenomas encountered in clinical practice. Giant adenomas are those > 4 cm in diameter. Less than 0.5% of pituitary adenomas encountered in neurosurgical practice are giant prolactinomas. Patients with giant prolactinomas typically present with highly elevated prolactin levels, endocrinologic disturbances, and neurologic symptoms from mass-induced pressure. Described here is an unusual case of a giant prolactinoma presenting with neck pain and structural compromise of the occipital condyles. Transnasal biopsy of the nasopharyngeal portion of the mass obtained tissue consistent with an atypical prolactinoma with p53 reactivity and a high Ki-67 index of 5%. Despite the size and invasiveness of the tumor, the patient had resolution of his clinical symptoms, dramatic reduction of his hyperprolactinemia, and near-complete disappearance of his tumor following medical treatment. PMID:26623246

  13. Bringing stakeholders together for urban health equity: hallmarks of a compromised process.

    PubMed

    Katz, Amy S; Cheff, Rebecca M; O'Campo, Patricia

    2015-01-01

    There is a global trend towards the use of ad hoc participation processes that seek to engage grassroots stakeholders in decisions related to municipal infrastructure, land use and services. We present the results of a scholarly literature review examining 14 articles detailing specific cases of these processes to contribute to the discussion regarding their utility in advancing health equity. We explore hallmarks of compromised processes, potential harms to grassroots stakeholders, and potential mitigating factors. We conclude that participation processes often cut off participation following the planning phase at the point of implementation, limiting convener accountability to grassroots stakeholders, and, further, that where participation processes yield gains, these are often due to independent grassroots action. Given the emphasis on participation in health equity discourse, this study seeks to provide a real world exploration of the pitfalls and potential harms of participation processes that is relevant to health equity theory and practice. PMID:26590020

  14. Reexamining the Phosphorus-Protein Dilemma: Does Phosphorus Restriction Compromise Protein Status?

    PubMed

    St-Jules, David E; Woolf, Kathleen; Pompeii, Mary Lou; Kalantar-Zadeh, Kamyar; Sevick, Mary Ann

    2016-05-01

    Dietary phosphorus restriction is recommended to help control hyperphosphatemia in hemodialysis patients, but many high-phosphorus foods are important sources of protein. In this review, we examine whether restricting dietary phosphorus compromises protein status in hemodialysis patients. Although dietary phosphorus and protein are highly correlated, phosphorus intakes can range up to 600 mg/day for a given energy and protein intake level. Furthermore, the collinearity of phosphorus and protein may be biased because the phosphorus burden of food depends on: (1) the presence of phosphate additives, (2) food preparation method, and (3) bioavailability of phosphorus, which are often unaccounted for in nutrition assessments. Ultimately, we argue that clinically relevant reductions in phosphorus intake can be made without limiting protein intake by avoiding phosphate additives in processed foods, using wet cooking methods such as boiling, and if needed, substituting high-phosphorus foods for nutritionally equivalent foods that are lower in bioavailable phosphorus. PMID:26873260

  15. The potential for sexual transmission to compromise control of Ebola virus outbreaks.

    PubMed

    Vinson, John E; Drake, John M; Rohani, Pejman; Park, Andrew W

    2016-06-01

    Recent evidence suggests that sexual contact may give rise to transmission of Ebola virus long after infection has been cleared from blood. We develop a simple mathematical model that incorporates contact transmission and sexual transmission parametrized from data relating to the 2013-2015 West African Ebola epidemic. The model explores scenarios where contact transmission is reduced following infection events, capturing behaviour change, and quantifies how these actions reducing transmission may be compromised by sexual transmission in terms of increasing likelihood, size and duration of outbreaks. We characterize the extent to which sexual transmission operates in terms of the probability of initial infection resolving to sexual infectiousness and the sexual transmission rate, and relate these parameters to the overall case burden. We find that sexual transmission can have large effects on epidemic dynamics (increasing attack ratios from 25% in scenarios without sexual transmission but with contact-transmission-reducing behaviour, up to 80% in equivalent scenarios with sexual transmission). PMID:27277951

  16. Is conceptual understanding compromised by a problem-solving emphasis in an introductory physics course?

    NASA Astrophysics Data System (ADS)

    Ridenour, J.; Feldman, G.; Teodorescu, R.; Medsker, L.; Benmouna, N.

    2013-01-01

    Developing competency in problem solving and enhancing conceptual understanding are primary objectives in introductory physics, and many techniques and tools are available to help instructors achieve them. Pedagogically, we use an easy-to-implement intervention, the ACCESS protocol, to develop and assess problem-solving skills in our SCALE-UP classroom environment for algebra-based physics. Based on our research and teaching experience, an important question has emerged: while primarily targeting improvements in problem-solving and cognitive development, is it necessary that conceptual understanding be compromised? To address this question, we gathered and analyzed information about student abilities, backgrounds, and instructional preferences. We report on our progress and give insights into matching the instructional tools to student profiles in order to achieve optimal learning in group-based active learning. The ultimate goal of our work is to integrate individual student learning needs into a pedagogy that moves students closer to expert-like status in problem solving.

  17. An interactive case study assessment. Nursing care of the cancer patient with compromised immunity: practicum cases.

    PubMed

    O'Neill, P N; Adsit, K I; Volker, D

    1991-01-01

    This demonstration will present an interactive videodisc (IVD) case study assessment of nursing care of the immunocompromised cancer patient. This module is the third part of a series of instructional IVD programs entitled Nursing Care of the Cancer Patient with Compromised Immunity. The series has been developed to provide education for fourth year nursing students, experienced nurses new to the field of oncology nursing, and for continuing education. The series has been developed to run on an InfoWindow platform and can also run on an M-Motion system. The demonstration will cover the rationale, treatment, content, and instructional strategies used in the module. The technology including the development platform and authoring environment will also be presented. PMID:1807768

  18. Five-Year Volumetric Evaluation of Periodontally Compromised Sites Restored by Immediate Implant Restorations.

    PubMed

    Tripodakis, Aris Petros; Gousias, Hercules; Mastoris, Michael; Likouresis, Dionysios

    2016-01-01

    The aim of the present study was the retrospective evaluation of the distance of the labial hard and soft tissue margins from the implant shoulder in 24 periodontally compromised sites that were restored by immediate implant restorations. Volumetric analysis was performed 5 years postoperatively using cone beam computed tomography with limited field of view. In all cases, a labial radiopaque plate component was apparent 5 years postoperatively coronal to the implant shoulder (3.1 ± 0.6 mm), supporting the soft tissue margin, which was extending above this level (5.2 ± 1.1 mm). In 12 of the sites, preoperative evaluation showed that this plate was missing at the time of implant placement. PMID:27560669

  19. Non-Surgical Management of Critically Compromised Airway Due to Dilatation of Interposed Colon

    PubMed Central

    Min, Jinsoo

    2016-01-01

    We present a rare case of critically compromised airway secondary to a massively dilated sequestered colon conduit after several revision surgeries. A 71-year-old male patient had several operations after the diagnosis of gastric cancer. After initial treatment of pneumonia in the pulmonology department, he was transferred to the surgery department for feeding jejunostomy because of recurrent aspiration. However, he had respiratory failure requiring mechanical ventilation. The chest computed tomography (CT) scan showed pneumonic consolidation at both lower lungs and massive dilatation of the substernal interposed colon compressing the trachea. The dilated interposed colon was originated from the right colon, which was sequestered after the recent esophageal reconstruction with left colon interposition resulting blind pouch at both ends. It was treated with CT-guided pigtail catheter drainage via right supraclavicular route, which was left in place for 2 weeks, and then removed. The patient remained well clinically, and was discharged home. PMID:27066087

  20. [Strategies of power and leadership for the development of nurses' social compromise].

    PubMed

    Alberdi Castell, R

    1998-01-01

    This article presents an analysis about power and leadership regarding the nursing profession in Spain and poses some strategies which, from the aforementioned perspective, allow the compromise nurses have with society to develop. This article has three sections: one which defines terms such as power, leadership, representative, corporation, ...; a second section which analyzes and makes proposals, wherein the current situation of the nursing profession is described in relation with the elements defined as the shapers of professional power, and proposals are posed along the lines of one to demand clear guidelines for nurses' professional role, to act in a "corporational" way, in positive terms, or to recognize the importance "informal" power networks hold; and finally, a section of conclusions. PMID:9739285

  1. Mycobacterium mucogenicum bacteremia in immune-compromised patients, 2008-2013.

    PubMed

    Abidi, M Z; Ledeboer, N; Banerjee, A; Hari, P

    2016-06-01

    Mycobacterium mucogenicum (MM) is a rapidly growing nontuberculous mycobacterium that may rarely cause bacteremia in immune-compromised hosts. All MM cases from 2008 to 2013 were analyzed across 4 risk groups: stem cell transplantation (SCT), hematologic malignancy, solid tumors, and others. Descriptive analysis was performed, as well as comparative analysis of neutropenic patients (absolute neutrophil count ≤1000/μL) with nonneutropenic patients. Of 39 MM cases, 27 patients had undergone SCT. Neutropenia was present in 12 patients. There was a significant difference in the presence of fever at the time of MM bacteremia between neutropenic and nonneutropenic groups (92% versus 42%; P=0.005). Central venous catheter (CVC) was present in 33 cases. All patients were treated with >1 antibiotic. Most frequently used combination antibiotic regimen involved clarithromycin and amikacin. Median duration of antibiotic treatment was 42days. Bacteremia resolved in all cases with CVC removal and combination antibiotic treatment. PMID:27117516

  2. Natural physical and biological processes compromise the long-term performance of compacted soil caps

    SciTech Connect

    Smith, E.D.

    1995-12-01

    Compacted soil barriers are components of essentially all caps placed on closed waste disposal sites. The intended functions of soil barriers in waste facility caps include restricting infiltration of water and release of gases and vapors, either independently or in combination with synthetic membrane barriers, and protecting other manmade or natural barrier components. Review of the performance of installed soil barriers and of natural processes affecting their performance indicates that compacted soil caps may function effectively for relatively short periods (years to decades), but natural physical and biological processes can be expected to cause them to fail in the long term (decades to centuries). This paper addresses natural physical and biological processes that compromise the performance of compacted soil caps and suggests measures that may reduce the adverse consequences of these natural failure mechanisms.

  3. Ranking of CMIP5-based global climate models for India using compromise programming

    NASA Astrophysics Data System (ADS)

    Srinivasa Raju, K.; Sonali, P.; Nagesh Kumar, D.

    2016-01-01

    Thirty-six Coupled Model Intercomparison Project-5-based global climate models (GCMs) are explored to evaluate the performance of maximum (T max) and minimum (T min) temperature simulations for India covering 40 grid points. Three performance indicators used for evaluating GCMs are correlation coefficient (CC), normalised root mean square error (NRMSE) and skill score (SS). Entropy method is applied to compute the weights of the three indicators employed. However, equal weights are also considered as part of sensitivity analysis studies. Compromise programming (CP), a distance-based decision-making technique, is employed to rank the GCMs. Group decision-making approach is used to aggregate the ranking patterns obtained for individual grid points. A simple but effective ensemble approach is also suggested.

  4. Artemisinin mimics calorie restriction to trigger mitochondrial biogenesis and compromise telomere shortening in mice

    PubMed Central

    Wu, Ming; Li, Si-Ming; Gao, Qian

    2015-01-01

    Calorie restriction is known to extend lifespan among organisms by a debating mechanism underlying nitric oxide-driven mitochondrial biogenesis. We report here that nitric oxide generators including artemisinin, sodium nitroprusside, and L-arginine mimics calorie restriction and resembles hydrogen peroxide to initiate the nitric oxide signaling cascades and elicit the global antioxidative responses in mice. The large quantities of antioxidant enzymes are correlated with the low levels of reactive oxygen species, which allow the down-regulation of tumor suppressors and accessory DNA repair partners, eventually leading to the compromise of telomere shortening. Accompanying with the up-regulation of signal transducers and respiratory chain signatures, mitochondrial biogenesis occurs with the elevation of adenosine triphosphate levels upon exposure of mouse skeletal muscles to the mimetics of calorie restriction. In conclusion, calorie restriction-triggered nitric oxide provides antioxidative protection and alleviates telomere attrition via mitochondrial biogenesis, thereby maintaining chromosomal stability and integrity, which are the hallmarks of longevity. PMID:25780774

  5. Airway compromise in the fetus and neonate: Prenatal assessment and perinatal management.

    PubMed

    Ryan, Greg; Somme, Stig; Crombleholme, Timothy M

    2016-08-01

    The fetus with a potentially obstructed airway can be identified on routine antenatal imaging. These cases should be referred to fetal care centers, which have the necessary expertise to fully evaluate and manage these fetuses and neonates appropriately. Complete airway obstruction may result in fetal hydrops and intrauterine demise. If a newborn infant has a compromised airway at delivery, the inability to secure its airway quickly may result in a hypoxic cerebral insult or death. In the most severely affected cases, prenatal, perinatal, or postnatal surgical intervention may be necessary. The timing of such an intervention will depend on the exact cause of the airway obstruction, other associated findings and the anticipated difficulty in establishing an airway at delivery. Fetal ultrasound and magnetic resonance imaging can differentiate between intrinsic and extrinsic airway obstruction, which allows for the optimal planning and management of the delivery and neonatal resuscitation. PMID:27084444

  6. Compromising abnormalities of the brachial plexus as displayed by magnetic resonance imaging.

    PubMed

    Collins, J D; Shaver, M L; Disher, A C; Miller, T Q

    1995-01-01

    Magnetic resonance images (MRI) of brachial plexus anatomy bilaterally, not possible by plain radiographs or CT, were presented to the Vascular Surgery, Neurology, and the Neurosurgery departments. Patients were requested for MRI of their brachial plexus. They were referred for imaging and the imaging results were presented to the faculty and housestaff. Our technique was accepted and adopted to begin referrals for MRI evaluation of brachial plexopathy. Over 175 patients have been studied. Eighty-five patients were imaged with the 1.5 Tesla magnet (Signa; General Electric Medical Systems, Milwaukee, WI) 3-D reconstruction MRI. Coronal, transverse (axial), oblique transverse, and sagittal plane T1-weighted and selected T2-weighted pulse sequences were obtained at 4-5 mm slice thickness, 40-45 full field of view, and a 512 x 256 size matrix. Saline water bags were used to enhance the signal between the neck and the thorax. Sites of brachial plexus compromise were demonstrated. Our technique with 3-D reconstruction increased the definition of brachial plexus pathology. The increased anatomical definition enabled the vascular surgeons and neurosurgeons to improve patient care. Brachial plexus in vivo anatomy as displayed by MRI, magnetic resonance angiography (MRA), and 3-D reconstruction offered an opportunity to augment the teaching of clinical anatomy to medical students and health professionals. Selected case presentations (bodybuilder, anomalous muscle, fractured clavicle, thyroid goiter, silicone breast implant rupture, and cervical rib) demonstrated compromise of the brachial plexus displayed by MRI. The MRI and 3-D reconstruction techniques, demonstrating the bilateral landmark anatomy, increased the definition of the clinical anatomy and resulted in greater knowledge of patient care management. PMID:7697507

  7. Clonal types of Toxoplasma gondii among immune compromised and immune competent individuals in Accra, Ghana.

    PubMed

    Ayi, Irene; Kwofie, Kofi Dadzie; Blay, Emmanuel Awusah; Osei, Joseph Harold Nyarko; Frempong, Kwadwo Kyeremeh; Koku, Roberta; Ghansah, Anita; Lartey, Margaret; Suzuki, Takashi; Boakye, Daniel Adjei; Koram, Kwadwo Ansah; Ohta, Nobuo

    2016-06-01

    There are three major clonal lineages, types I, II, and III, of Toxoplasma gondii known to cause human toxoplasmosis worldwide. Toxoplasma gondii infections have, however, not been genotyped in Ghana. This study detected the clonal types infecting immune compromised and immune competent individuals in Accra, Ghana. Blood samples were obtained from 148 HIV seropositive pre-antiretroviral therapy individuals (0≤CD4(+) T-cell count/μl blood ≤200) at the Fevers Unit and 149 HIV seronegative apparently healthy blood donors at the blood bank, all of the Korle-Bu Teaching Hospital. Genomic DNA was extracted and multilocus genotyping conducted by nested PCR-RFLP analysis using GRA6, SAG3, and BTUB gene markers. Among the HIV seropositive participants, 54.7% (81/148) were T. gondii DNA positive for any of the markers. Out of the 81, 42.0% (34) were positive for SAG3 only, 30.9% (25) for GRA6 only, 24.7% (20) for both SAG3 and GRA6, and 2.5% (2) for SAG3, GRA6, and BTUB. Overall, 93.8% of the positives were of clonal type II, 1.2% type I, while 4.9% (4) were atypical or mixed types (I and II). In the healthy blood donors, prevalence of T. gondii DNA positivity was 3.4% (5/149) by SAG3 and/or GRA6; among them, 60.0% (3/5) were type I, and the remaining 40.0%, type II. This study showed a relatively high prevalence of active T. gondii infections in immune compromised patients and low prevalence in immune competent individuals in Accra. Type II was highly prevalent. Detection of T. gondii in blood donors raises public health concerns and screening for T. gondii should be considered. PMID:26775819

  8. β-Cell Ca(2+) dynamics and function are compromised in aging.

    PubMed

    Barker, Christopher J; Li, Luosheng; Köhler, Martin; Berggren, Per-Olof

    2015-01-01

    Defects in pancreatic β-cell function and survival are key components in type 2 diabetes (T2D). An age-dependent deterioration in β-cell function has also been observed, but little is known about the molecular mechanisms behind this phenomenon. Our previous studies indicate that the regulation of cytoplasmic free Ca(2+) concentration ([Ca(2+)]i) may be critical and that this is dependent on the proper function of the mitochondria. The [Ca(2+)]i dynamics of the pancreatic β-cell are driven by an interplay between glucose-induced influx of extracellular Ca(2+) via voltage-dependent Ca(2+) channels and the inositol 1,4,5-trisphosphate (Ins(1,4,5)P3)-mediated liberation of Ca(2+) from intracellular stores. Our previous work has indicated a direct relationship between disruption of Ins(1,4,5)P3-mediated Ca(2+) regulation and loss of β-cell function, including disturbed [Ca(2+)]i dynamics and compromised insulin secretion. To investigate these processes in aging we used three mouse models, a premature aging mitochondrial mutator mouse, a mature aging phenotype (C57BL/6) and an aging-resistant phenotype (129). Our data suggest that age-dependent impairment in mitochondrial function leads to modest changes in [Ca(2+)]i dynamics in mouse β-cells, particularly in the pattern of [Ca(2+)]i oscillations. These changes are driven by modifications in both PLC/Ins(1,4,5)P3-mediated Ca(2+) mobilization from intracellular stores and decreased β-cell Ca(2+) influx over the plasma membrane. Our findings underscore an important concept, namely that even relatively small, time-dependent changes in β-cell signal-transduction result in compromised insulin release and in a diabetic phenotype. PMID:25282681

  9. Do low-income lone mothers compromise their nutrition to feed their children?

    PubMed Central

    McIntyre, Lynn; Glanville, N. Theresa; Raine, Kim D.; Dayle, Jutta B.; Anderson, Bonnie; Battaglia, Noreen

    2003-01-01

    Background Women who live in disadvantaged circumstances in Canada exhibit dietary intakes below recommended levels, but their children often do not. One reason for this difference may be that mothers modify their own food intake to spare their children nutritional deprivation. The objective of our study was to document whether or not low-income lone mothers compromise their own diets to feed their children. Methods We studied 141 low-income lone mothers with at least 2 children under the age of 14 years who lived in Atlantic Canada. Women were identified through community organizations using a variety of recruitment strategies. The women were asked weekly for 1 month to recall their food intake over the previous 24 hours; they also reported their children's (n = 333) food intake. Mothers also completed a questionnaire about “food insecurity,” that is, a lack of access to adequate, nutritious food through socially acceptable means, during each interview. Results Household food insecurity was reported by 78% of mothers during the study month. Mothers' dietary intakes and the adequacy of intake were consistently poorer than their children's intake overall and over the course of a month. The difference in adequacy of intake between mothers and children widened from Time 1, when the family had the most money to purchase food, to Time 4, when the family had the least money. The children experienced some improvement in nutritional intake at Time 3, which was possibly related to food purchases for them associated with receipt of the Child Tax Benefit Credit or the Goods and Services Tax Credit. Interpretation Our study demonstrates that low-income lone mothers compromise their own nutritional intake in order to preserve the adequacy of their children's diets. PMID:12642423

  10. Sustained NMDA receptor activation by spreading depolarizations can initiate excitotoxic injury in metabolically compromised neurons

    PubMed Central

    Aiba, Isamu; Shuttleworth, C William

    2012-01-01

    Spreading depolarizations (SDs) are slowly propagating waves of near-complete neuronal and glial depolarization. SDs have been recorded in patients with brain injury, and the incidence of SD significantly correlates with outcome severity. Although it is well accepted that the ionic dyshomeostasis of SD presents a severe metabolic burden, there is currently limited understanding of SD-induced injury processes at a cellular level. In the current study we characterized events accompanying SD in the hippocampal CA1 region of murine brain slices, using whole-cell recordings and single-cell Ca2+ imaging. We identified an excitatory phase that persisted for approximately 2 min following SD onset, and accompanied with delayed dendritic ionic dyshomeostasis. The excitatory phase coincided with a significant increase in presynaptic glutamate release, evidenced by a transient increase in spontaneous EPSC frequency and paired-pulse depression of evoked EPSCs. Activation of NMDA receptors (NMDARs) during this late excitatory phase contributed to the duration of individual neuronal depolarizations and delayed recovery of extracellular slow potential changes. Selectively targeting the NMDAR activation following SD onset (by delayed pressure application of a competitive NMDAR antagonist) significantly decreased the duration of cellular depolarizations. Recovery of dendritic Ca2+ elevations following SD were also sensitive to delayed NMDA antagonist application. Partial inhibition of neuronal energy metabolism converted SD into an irrecoverable event with persistent Ca2+ overload and membrane compromise. Delayed NMDAR block was sufficient to prevent these acute injurious events in metabolically compromised neurons. These results identify a significant contribution of a late component of SD that could underlie neuronal injury in pathological circumstances. PMID:22907056

  11. Ionoregulatory Aspects of the Osmorespiratory Compromise during Acute Environmental Hypoxia in 12 Tropical and Temperate Teleosts.

    PubMed

    Robertson, Lisa M; Val, Adalberto Luis; Almeida-Val, Vera F; Wood, Chris M

    2015-01-01

    In the traditional osmorespiratory compromise, as seen in the hypoxia-intolerant freshwater rainbow trout (Oncorhynchus mykiss), the branchial modifications that occur to improve O2 uptake during hypoxia result in unfavorable increases in the fluxes of ions and water. However, at least one hypoxia-tolerant freshwater species, the Amazonian oscar (Astronotus ocellatus), shows exactly the opposite: decreased branchial flux rates of ions, water, and nitrogenous wastes during acute hypoxia. In order to find out whether the two strategies were widespread, we used a standard 2-h normoxia, 2-h hypoxia (20%-30% saturation), 2-h normoxic recovery protocol to survey 10 other phylogenetically diverse tropical and temperate species. Unidirectional influx and efflux rates of Na(+) and net flux rates of K(+), ammonia, and urea-N were measured. The flux reduction strategy was seen only in one additional species, the Amazonian tambaqui (Colossoma macropomum), which is similarly hypoxia tolerant and lives in the same ion-poor waters as the oscar. However, five other species exhibited evidence of the increased flux rates typical of the traditional osmorespiratory compromise in the trout: the rosaceu tetra (Hyphessobrycon bentosi rosaceus), the moenkhausia tetra (Moenkhausia diktyota), the bluegill sunfish (Lepomis macrochirus), the zebra fish (Danio rerio), and the goldfish (Carassius auratus). Four other species exhibited no marked flux changes during hypoxia: the cardinal tetra (Paracheirodon axelrodi), the hemigrammus tetra (Hemigrammus rhodostomus), the pumpkinseed sunfish (Lepomis gibbosus), and the Atlantic killifish (Fundulus heteroclitus). Overall, a diversity of strategies exist; we speculate that these may be linked to differences in habitat and/or lifestyle. PMID:26052633

  12. Compromising economic cost and air pollutant emissions of municipal solid waste management strategies by fuzzy multiobjective optimization model.

    PubMed

    Chang, Yao-Jen; Lin, Min-Der

    2013-06-01

    Municipal solid waste management (MSWM) is an important environmental challenge and subject in urban planning. A sustainable MSWM strategy should consider not only economic efficiency but also life-cycle assessment of environmental impact. This study employs the fuzzy multiobjective linear programming (FMOLP) technique to find the optimal compromise between economic optimization and pollutant emission reduction for the MSWM strategy. Taichung City in Taiwan is evaluated as a case study. The results indicate that the optimal compromise MSWM strategy can reduce significant amounts of pollutant emissions and still achieve positive net profits. Minimization of the sulfur oxide (SOx) and nitrogen oxide (NOx) emissions are the two major priorities in achieving this optimal compromise strategy when recyclables recovery rate is lower; however minimization of the carbon monoxide (CO) and particulate matter (PM) emissions become priority factors when recovery rate is higher. PMID:23858997

  13. Transient inhibition of cell proliferation does not compromise self-renewal of mouse embryonic stem cells

    SciTech Connect

    Wang, Ruoxing; Guo, Yan-Lin

    2012-10-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remains unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. -- Highlights: Black-Right-Pointing-Pointer Inhibition of Cdks slows down mESCs proliferation. Black-Right-Pointing-Pointer mESCs display remarkable recovery capacity from short-term cell cycle interruption. Black-Right-Pointing-Pointer Short-term cell cycle interruption does not compromise mESC self-renewal. Black

  14. Late, not early, stages of Kanizsa shape perception are compromised in schizophrenia

    PubMed Central

    Keane, Brian P.; Joseph, Jamie; Silverstein, Steven M.

    2014-01-01

    Background Schizophrenia is a devastating psychiatric disorder characterized by symptoms including delusions, hallucinations, and disorganized thought. Kanizsa shape perception is a basic visual process that builds illusory contour and shape representations from spatially segregated edges. Recent studies have shown that schizophrenia patients exhibit abnormal electrophysiological signatures during Kanizsa shape perception tasks, but it remains unclear how these abnormalities are manifested behaviorally and whether they arise from early or late levels in visual processing. Method To address this issue, we had healthy controls and schizophrenia patients discriminate quartets of sectored circles that either formed or did not form illusory shapes (illusory and fragmented conditions, respectively). Half of the trials in each condition incorporated distractor lines, which are known to disrupt illusory contour formation and thereby worsen illusory shape discrimination. Results Relative to their respective fragmented conditions, patients performed worse than controls in the illusory discrimination. Conceptually disorganized patients—characterized by their incoherent manner of speaking—were primarily driving the effect. Regardless of patient status or disorganization levels, distractor lines worsened discrimination more in the illusory than the fragmented condition, indicating that all groups could form illusory contours. Conclusion People with schizophrenia form illusory contours but are less able to utilize those contours to discern global shape. The impairment is especially related to the ability to think and speak coherently. These results suggest that Kanizsa shape perception incorporates an early illusory contour formation stage and a later, conceptually-mediated shape integration stage, with the latter being primarily compromised in schizophrenia. PMID:24513023

  15. Abnormal splicing switch of DMD's penultimate exon compromises muscle fibre maintenance in myotonic dystrophy.

    PubMed

    Rau, Frédérique; Lainé, Jeanne; Ramanoudjame, Laetitita; Ferry, Arnaud; Arandel, Ludovic; Delalande, Olivier; Jollet, Arnaud; Dingli, Florent; Lee, Kuang-Yung; Peccate, Cécile; Lorain, Stéphanie; Kabashi, Edor; Athanasopoulos, Takis; Koo, Taeyoung; Loew, Damarys; Swanson, Maurice S; Le Rumeur, Elisabeth; Dickson, George; Allamand, Valérie; Marie, Joëlle; Furling, Denis

    2015-01-01

    Myotonic Dystrophy type 1 (DM1) is a dominant neuromuscular disease caused by nuclear-retained RNAs containing expanded CUG repeats. These toxic RNAs alter the activities of RNA splicing factors resulting in alternative splicing misregulation and muscular dysfunction. Here we show that the abnormal splicing of DMD exon 78 found in dystrophic muscles of DM1 patients is due to the functional loss of MBNL1 and leads to the re-expression of an embryonic dystrophin in place of the adult isoform. Forced expression of embryonic dystrophin in zebrafish using an exon-skipping approach severely impairs the mobility and muscle architecture. Moreover, reproducing Dmd exon 78 missplicing switch in mice induces muscle fibre remodelling and ultrastructural abnormalities including ringed fibres, sarcoplasmic masses or Z-band disorganization, which are characteristic features of dystrophic DM1 skeletal muscles. Thus, we propose that splicing misregulation of DMD exon 78 compromises muscle fibre maintenance and contributes to the progressive dystrophic process in DM1. PMID:26018658

  16. Compromising the 19S proteasome complex protects cells from reduced flux through the proteasome

    PubMed Central

    Tsvetkov, Peter; Mendillo, Marc L; Zhao, Jinghui; Carette, Jan E; Merrill, Parker H; Cikes, Domagoj; Varadarajan, Malini; van Diemen, Ferdy R; Penninger, Josef M; Goldberg, Alfred L; Brummelkamp, Thijn R; Santagata, Sandro; Lindquist, Susan

    2015-01-01

    Proteasomes are central regulators of protein homeostasis in eukaryotes. Proteasome function is vulnerable to environmental insults, cellular protein imbalance and targeted pharmaceuticals. Yet, mechanisms that cells deploy to counteract inhibition of this central regulator are little understood. To find such mechanisms, we reduced flux through the proteasome to the point of toxicity with specific inhibitors and performed genome-wide screens for mutations that allowed cells to survive. Counter to expectation, reducing expression of individual subunits of the proteasome's 19S regulatory complex increased survival. Strong 19S reduction was cytotoxic but modest reduction protected cells from inhibitors. Protection was accompanied by an increased ratio of 20S to 26S proteasomes, preservation of protein degradation capacity and reduced proteotoxic stress. While compromise of 19S function can have a fitness cost under basal conditions, it provided a powerful survival advantage when proteasome function was impaired. This means of rebalancing proteostasis is conserved from yeast to humans. DOI: http://dx.doi.org/10.7554/eLife.08467.001 PMID:26327695

  17. An adaptive compromise programming method for multi-objective path optimization

    NASA Astrophysics Data System (ADS)

    Li, Rongrong; Leung, Yee; Lin, Hui; Huang, Bo

    2013-04-01

    Network routing problems generally involve multiple objectives which may conflict one another. An effective way to solve such problems is to generate a set of Pareto-optimal solutions that is small enough to be handled by a decision maker and large enough to give an overview of all possible trade-offs among the conflicting objectives. To accomplish this, the present paper proposes an adaptive method based on compromise programming to assist decision makers in identifying Pareto-optimal paths, particularly for non-convex problems. This method can provide an unbiased approximation of the Pareto-optimal alternatives by adaptively changing the origin and direction of search in the objective space via the dynamic updating of the largest unexplored region till an appropriately structured Pareto front is captured. To demonstrate the efficacy of the proposed methodology, a case study is carried out for the transportation of dangerous goods in the road network of Hong Kong with the support of geographic information system. The experimental results confirm the effectiveness of the approach.

  18. 2016 Rio Olympic Games: Can the schedule of events compromise athletes' performance?

    PubMed

    Rosa, João Paulo P; Rodrigues, Dayane F; Silva, Andressa; de Moura Simim, Mário Antônio; Costa, Varley T; Noce, Franco; de Mello, Marco Túlio

    2016-01-01

    The organizing committee of the 2016 Rio Olympic Games recently announced that some of the preliminary and final competitions will be held at night. The present article discusses the potential harmful effects of these late-night competitions on sleep, circadian rhythms and athletic performance during the Olympic Games. Specifically, night-time competition could lead to injury and may compromise an athlete's decision-making, attentional, physiological and other processes. Consequently, these impacts could negatively affect the performance of athletes and their teams. Thus, it is suggested that technical commissions take special care when creating strategies to minimize harm to the athletes by considering factors such as light exposure, melatonin intake, sleep hygiene and scheduled naps, and training at local competition time. Furthermore, it is necessary for specialists in chronobiology and sleep to engage with members of the national teams to develop an activity schedule for physical, technical, tactical and psychological preparation that accounts for circadian rhythms, thereby creating the best possible environment for the athletes to achieve their ideal performance. PMID:27003630

  19. Genetic Drift Can Compromise Mitochondrial Replacement by Nuclear Transfer in Human Oocytes.

    PubMed

    Yamada, Mitsutoshi; Emmanuele, Valentina; Sanchez-Quintero, Maria J; Sun, Bruce; Lallos, Gregory; Paull, Daniel; Zimmer, Matthew; Pagett, Shardonay; Prosser, Robert W; Sauer, Mark V; Hirano, Michio; Egli, Dieter

    2016-06-01

    Replacement of mitochondria through nuclear transfer between oocytes of two different women has emerged recently as a strategy for preventing inheritance of mtDNA diseases. Although experiments in human oocytes have shown effective replacement, the consequences of small amounts of mtDNA carryover have not been studied sufficiently. Using human mitochondrial replacement stem cell lines, we show that, even though the low levels of heteroplasmy introduced into human oocytes by mitochondrial carryover during nuclear transfer often vanish, they can sometimes instead result in mtDNA genotypic drift and reversion to the original genotype. Comparison of cells with identical oocyte-derived nuclear DNA but different mtDNA shows that either mtDNA genotype is compatible with the nucleus and that drift is independent of mitochondrial function. Thus, although functional replacement of the mitochondrial genome is possible, even low levels of heteroplasmy can affect the stability of the mtDNA genotype and compromise the efficacy of mitochondrial replacement. PMID:27212703

  20. Abnormal splicing switch of DMD's penultimate exon compromises muscle fibre maintenance in myotonic dystrophy

    PubMed Central

    Rau, Frédérique; Lainé, Jeanne; Ramanoudjame, Laetitita; Ferry, Arnaud; Arandel, Ludovic; Delalande, Olivier; Jollet, Arnaud; Dingli, Florent; Lee, Kuang-Yung; Peccate, Cécile; Lorain, Stéphanie; Kabashi, Edor; Athanasopoulos, Takis; Koo, Taeyoung; Loew, Damarys; Swanson, Maurice S.; Le Rumeur, Elisabeth; Dickson, George; Allamand, Valérie; Marie, Joëlle; Furling, Denis

    2015-01-01

    Myotonic Dystrophy type 1 (DM1) is a dominant neuromuscular disease caused by nuclear-retained RNAs containing expanded CUG repeats. These toxic RNAs alter the activities of RNA splicing factors resulting in alternative splicing misregulation and muscular dysfunction. Here we show that the abnormal splicing of DMD exon 78 found in dystrophic muscles of DM1 patients is due to the functional loss of MBNL1 and leads to the re-expression of an embryonic dystrophin in place of the adult isoform. Forced expression of embryonic dystrophin in zebrafish using an exon-skipping approach severely impairs the mobility and muscle architecture. Moreover, reproducing Dmd exon 78 missplicing switch in mice induces muscle fibre remodelling and ultrastructural abnormalities including ringed fibres, sarcoplasmic masses or Z-band disorganization, which are characteristic features of dystrophic DM1 skeletal muscles. Thus, we propose that splicing misregulation of DMD exon 78 compromises muscle fibre maintenance and contributes to the progressive dystrophic process in DM1. PMID:26018658

  1. Loss of CARD9-mediated innate activation attenuates severe influenza pneumonia without compromising host viral immunity.

    PubMed

    Uematsu, Takayuki; Iizasa, Ei'ichi; Kobayashi, Noritada; Yoshida, Hiroki; Hara, Hiromitsu

    2015-01-01

    Influenza virus (IFV) infection is a common cause of severe viral pneumonia associated with acute respiratory distress syndrome (ARDS), which is difficult to control with general immunosuppressive therapy including corticosteroids due to the unfavorable effect on viral replication. Studies have suggested that the excessive activation of the innate immunity by IFV is responsible for severe pathologies. In this study, we focused on CARD9, a signaling adaptor known to regulate innate immune activation through multiple innate sensor proteins, and investigated its role in anti-IFV defense and lung pathogenesis in a mouse model recapitulating severe influenza pneumonia with ARDS. We found that influenza pneumonia was dramatically attenuated in Card9-deficient mice, which showed improved mortality with reduced inflammatory cytokines and chemokines in the infected lungs. However, viral clearance, type-I interferon production, and the development of anti-viral B and T cell immunity were not compromised by CARD9 deficiency. Syk or CARD9-deficient DCs but not macrophages showed impaired cytokine but not type-I interferon production in response to IFV in vitro, indicating a possible role for the Syk-CARD9 pathway in DCs in excessive inflammation of IFV-infected lungs. Therefore, inhibition of this pathway is an ideal therapeutic target for severe influenza pneumonia without affecting viral clearance. PMID:26627732

  2. Transposition of brachiobasilic arteriovenous fistulae: improving the cosmetic effect without compromising patency.

    PubMed

    van Dellen, David; Junejo, Muneer; Khambalia, Hussein; Campbell, Babatunde

    2016-01-01

    Introduction Subjects who undergo haemodialysis are living longer, which necessitates increasingly complex procedures for formation of arteriovenous fistulas. Basilic veins provide valuable additional venous 'real estate' but surgical transposition of vessels is required, which required a cosmetically disfiguring incision. A minimally invasive transposition method provides an excellent aesthetic alternative without compromised outcomes. Methods A retrospective review was made of minimally invasive brachiobasilic fistula transpositions (using two short incisions of <4 cm) between February 2005 and July 2011. Primary endpoints were one-year patency as well as the perioperative and late complications of the procedure. Results Thirty-one patients underwent 32 transposition procedures (eight pre-dialysis cases; 24 haemodialysis patients). All patients were treated with a minimally invasive method. Thirty-one procedures resulted in primary patency, with the single failure refashioned successfully. The only indication for a more invasive approach was intraoperative complications (two haematomas). All other complications presented late and were amenable to intervention (one aneurysm, one peri-anastomotic stricture). Conclusion Formation of arteriovenous fistulae using minimally invasive methods is a novel approach that ensures fistula patency with improved aesthetic outcomes and without significant morbidity. PMID:26688395

  3. The Munsell Color System: a scientific compromise from the world of art.

    PubMed

    Cochrane, Sally

    2014-09-01

    Color systems make accurate color specification and matching possible in science, art, and industry by defining a coordinate system for all possible color perceptions. The Munsell Color System, developed by the artist Albert Henry Munsell in the early twentieth century, has influenced color science to this day. I trace the development of the Munsell Color System from its origins in the art world to its acceptance in the scientific community. Munsell's system was the first to accurately and quantitatively describe the psychological experience of color. By considering the problems that color posed for Munsell's art community and examining his diaries and published material, I conclude that Munsell arrived at his results by remaining agnostic as to the scientific definition of color, while retaining faith that color perceptions could be objectively quantified. I argue that Munsell was able to interest the scientific community in his work because color had become a controversial topic between physicists and psychologists. Parts of Munsell's system appealed to each field, making it a workable compromise. For contrast, I suggest that three contemporary scientists with whom Munsell had contact--Wilhelm Ostwald, Ogden Rood, and Edward Titchener--did not reach the same conclusions in their color systems because they started from scientific assumptions about the nature of color. PMID:25812356

  4. Compromised NK Cell-Mediated Antibody-Dependent Cellular Cytotoxicity in Chronic SIV/SHIV Infection

    PubMed Central

    He, Xuan; Li, Dan; Luo, Zhenwu; Liang, Hua; Peng, Hong; Zhao, Yangyang; Wang, Nidan; Liu, Donghua; Qin, Chuan; Wei, Qiang; Yan, Huimin; Shao, Yiming

    2013-01-01

    Increasing evidence indicates that antibody-dependent cellular cytotoxicity (ADCC) contributes to the control of HIV/SIV infection. However, little is known about the ADCC function of natural killer (NK) cells in non-human primate model. Here we demonstrated that ADCC function of NK cells was significantly compromised in chronic SIV/SHIV infection, correlating closely with the expression of FcγRIIIa receptor (CD16) on NK cells. CD32, another class of IgG Fc receptors, was identified on NK cells with higher expression in the infected macaques and the blockade of CD32 impacted the ability of NK cells to respond to antibody-coated target cells. The inhibition of matrix metalloproteases (MMPs), a group of enzymes normally involved in tissue/receptor remodeling, could restore NK cell-mediated ADCC with increased CD16 expression on macaque NK cells. These data offer a clearer understanding of NK cell-mediated ADCC in rhesus macaques, which will allow us to evaluate the ADCC repertoire arising from preclinical vaccination studies in non-human primates and inform us in the future design of effective HIV vaccination strategies. PMID:23424655

  5. 'Compromise' in Echolocation Calls between Different Colonies of the Intermediate Leaf-Nosed Bat (Hipposideros larvatus).

    PubMed

    Chen, Yi; Liu, Qi; Su, Qianqian; Sun, Yunxiao; Peng, Xingwen; He, Xiangyang; Zhang, Libiao

    2016-01-01

    Each animal population has its own acoustic signature which facilitates identification, communication and reproduction. The sonar signals of bats can convey social information, such as species identity and contextual information. The goal of this study was to determine whether bats adjust their echolocation call structures to mutually recognize and communicate when they encounter the bats from different colonies. We used the intermediate leaf-nosed bats (Hipposideros larvatus) as a case study to investigate the variations of echolocation calls when bats from one colony were introduced singly into the home cage of a new colony or two bats from different colonies were cohabitated together for one month. Our experiments showed that the single bat individual altered its peak frequency of echolocation calls to approach the call of new colony members and two bats from different colonies adjusted their call frequencies toward each other to a similar frequency after being chronically cohabitated. These results indicate that the 'compromise' in echolocation calls might be used to ensure effective mutual communication among bats. PMID:27029005

  6. Compromised intestinal epithelial barrier induces adaptive immune compensation that protects from colitis

    PubMed Central

    Khounlotham, Manirath; Kim, Wooki; Peatman, Eric; Nava, Porfirio; Medina-Contreras, Oscar; Addis, Caroline; Koch, Stefan; Fournier, Benedicte; Nusrat, Asma; Denning, Timothy L.; Parkos, Charles A.

    2012-01-01

    SUMMARY Mice lacking Junctional Adhesion Molecule A (JAM-A, encoded by F11r) exhibit enhanced intestinal epithelial permeability, bacterial translocation, and elevated colonic lymphocyte numbers, yet do not develop colitis. To investigate the contribution of adaptive immune compensation in response to increased intestinal epithelial permeability, we examined the susceptibility of F11r-/-Rag1-/- mice to acute colitis. Although negligible contributions of adaptive immunity in F11r-/-Rag1-/- mice were observed, F11r-/-Rag1-/- mice exhibited increased microflora-dependent colitis. Elimination of T cell subsets and cytokine analyses revealed a protective role for TGF-β-producing CD4+ T cells in F11r-/- mice. Additionally, loss of JAM-A resulted in elevated mucosal and serum IgA that was dependent upon CD4+ T cells and TGF-β. Absence of IgA in F11r+/+Igha-/- mice did not affect disease whereas F11r-/-Igha-/- mice displayed markedly increased susceptibility to acute injury induced colitis. These data establish a role for adaptive immune mediated protection from acute colitis under conditions of intestinal epithelial barrier compromise. PMID:22981539

  7. Food security: the challenge of increasing wheat yield and the importance of not compromising food safety

    PubMed Central

    Curtis, T; Halford, N G

    2014-01-01

    Current wheat yield and consumption is considered in the context of the historical development of wheat, from early domestication through to modern plant breeding, the Green Revolution and wheat’s place as one of the world’s most productive and important crops in the 21st Century. The need for further improvement in the yield potential of wheat in order to meet current and impending challenges is discussed, including rising consumption and the demand for grain for fuel as well as food. Research on the complex genetics underlying wheat yield is described, including the identification of quantitative trait loci and individual genes, and the prospects of biotechnology playing a role in wheat improvement in the future are discussed. The challenge of preparing wheat to meet the problems of drought, high temperature and increasing carbon dioxide concentration that are anticipated to come about as a result of climate change is also reviewed. Wheat yield must be increased while not compromising food safety, and the emerging problem of processing contaminants is reviewed, focussing in particular on acrylamide, a contaminant that forms from free asparagine and reducing sugars during high temperature cooking and processing. Wheat breeders are strongly encouraged to consider the contaminant issue when breeding for yield. PMID:25540461

  8. Hint1 knockout results in a compromised activation of protein kinase C gamma in the brain.

    PubMed

    Zhang, Fan; Fang, Zhenfei; Wang, Jia Bei

    2015-10-01

    Previous studies have implicated a role of the histidine triad nucleotide-binding protein 1 (Hint1) in the pathogenesis of schizophrenia. Protein kinase C gamma (PKCγ) could be potentially involved in the Hint1-implicated pathogenesis since PKCγ was identified as a Hint1 interacting protein. Recently, a debate was brought forward from the understanding how Hint1 affects the expression and activity of PKCγ in the brain. In the present study, we use Hint1 knockout mice and biochemical analysis to define the effect of Hint1 on protein PKCγ. Our data reveal that Hint1-deficiency in mouse brains led to increased protein levels of PKCγ in the cortex and hippocampus, the striatum and thalamus and amygdala. Without stimulation, PKCγ protein in Hint1-deficient brain displayed a basal activity that was reflected by control-leveled phosphorylations of PKCγ T514 and T674 at its kinase domain. Upon psycho-stimulation, both sites of PKCγ T514 and T674 were activated in these brain structures via phosphorylation; however, the phosphorylation level at the site of PKCγ T674 apparently attenuated in Hint1-deficient mice compared to wild-type control. Thus, we conclude that Hint1 deficiency leads to an increased protein level of PKCγ in the brain and a compromised activation response of PKCγ upon stimulation. These findings suggest an inhibitory role of Hint1 on the protein PKCγ in the brain and an impaired PKCγ-mediated phosphorylation signal in Hint1-deficient neuron. PMID:26133792

  9. Reduction of tissue injury without compromising stone comminution in shock wave lithotripsy

    NASA Astrophysics Data System (ADS)

    Zhou, Yufeng; Auge, Brian; Preminger, Glenn M.; Zhong, Pei

    2002-05-01

    To ameliorate vascular injury without compromising stone comminution in shock wave lithotripsy, we have recently developed an in situ pulse superposition technique to suppress large intraluminal bubble expansion [Zhong and Zhou, J. Acoust. Soc. Am. 110, 3283-3291 (2001)]. This strategy was implemented using a simple modification of a HM-3 lithotripter reflector. In this work, further optimization of the reflector geometry was carried out based on theoretical analysis and in vitro pressure waveform measurements using a fiber optical hydrophone. Using the upgraded reflector, no rupture of a cellulose hollow fiber (i.d.=0.2 mm) vessel phantom could be observed around the lithotripter beam focus even after 200 shocks at 24 kV. In comparison, less than 50 shocks were needed to cause a rupture of the vessel phantom using the original reflector at 20 kV. At corresponding output settings, stone comminution is comparable between the two reflector configurations, although the size of the fragments produced by the upgraded reflector is slightly larger. In addition, preliminary results from animal studies have demonstrated a significant reduction in tissue injury using the upgraded reflector, which confirms the validity of this approach in vivo. [Work supported by NIH.

  10. Radiation-treated ready-to-eat (RTE) chicken breast Adobo for immuno-compromised patients.

    PubMed

    Feliciano, Chitho P; De Guzman, Zenaida M; Tolentino, Levelyn Mitos M; Cobar, Maria Lucia C; Abrera, Gina B

    2014-11-15

    Usually in hospitals low-bacterial diets are served to immuno-compromised patients (ICPs). However, low-bacterial diets still pose a high risk of microbial infections and limit the food selection of the patients. Thus, pathogen-free dishes must be made available. This study presents the development of pathogen-free ready-to-eat (RTE) Filipino ethnic food chicken breast Adobo, sterilized by exposure to high-dose gamma rays (25 kGy) in combination with conventional treatments. Frozen vacuum-packed samples artificially inoculated with Escherichia coli, Listeria monocytogenes, Bacillus cereus, Staphylococcus aureus and Salmonella enterica subsp. enterica serovar Typhimurium, were exposed to 25 kGy gamma radiation for complete sterilization. Microbial quality and sterility of the samples were analysed following 15, 30, and 60 days of storage at -4°C. The effects of high-dose gamma irradiation on the nutritional quality and sensory characteristics of RTE chicken breast Adobo were also evaluated. PMID:24912709

  11. Sampling of prenatal and postnatal offspring from individual rat dams enhances animal use without compromising development

    NASA Technical Reports Server (NTRS)

    Alberts, J. R.; Burden, H. W.; Hawes, N.; Ronca, A. E.

    1996-01-01

    To assess prenatal and postnatal developmental status in the offspring of a group of animals, it is typical to examine fetuses from some of the dams as well as infants born to the remaining dams. Statistical limitations often arise, particularly when the animals are rare or especially precious, because all offspring of the dam represent only a single statistical observation; littermates are not independent observations (biologically or statistically). We describe a study in which pregnant laboratory rats were laparotomized on day 7 of gestation (GD7) to ascertain the number and distribution of uterine implantation sites and were subjected to a simulated experience on a 10-day space shuttle flight. After the simulated landing on GD18, rats were unilaterally hysterectomized, thus providing a sample of fetuses from 10 independent uteruses, followed by successful vaginal delivery on GD22, yielding postnatal samples from 10 uteruses. A broad profile of maternal and offspring morphologic and physiologic measures indicated that these novel sampling procedures did not compromise maternal well-being and maintained normal offspring development and function. Measures included maternal organ weights and hormone concentrations, offspring body size, growth, organ weights, sexual differentiation, and catecholamine concentrations.

  12. A GmAOX2b antisense gene compromises vegetative growth and seed production in soybean.

    PubMed

    Chai, Tsun-Thai; Simmonds, Daina; Day, David A; Colmer, Timothy D; Finnegan, Patrick M

    2012-07-01

    The alternative oxidase mediates the cyanide-resistant respiratory pathway in plant mitochondria. In non-thermogenic plants, the role of alternative oxidase in plant growth and development is not well understood. Soybean (Glycine max) lines carrying a GmAOX2b antisense gene had compromised vegetative growth and reproductive performance under typical glasshouse growth conditions. The reduction in vegetative growth was demonstrated by reduction in shoot height, the number of leaves per plant and the green leaf area. Antisense plants also had decreased pod formation and seed to pod ratios, which together led to a reduction in the number and total mass of seed produced. The negative effects of the antisense gene on pod set, seed set, ovule availability and total seed mass were primarily confined to the branches, rather than the main stem. The preferential effect of alternative oxidase suppression in the branches is discussed in relation to the reproductive potential of soybean under stress. Taken together, these results demonstrate that alternative oxidase provides the benefit of sustaining plant vegetative growth and reproductive capacity in soybean. PMID:22307678

  13. Mutation in MRPS34 Compromises Protein Synthesis and Causes Mitochondrial Dysfunction

    PubMed Central

    Richman, Tara R.; Ermer, Judith A.; Davies, Stefan M. K.; Perks, Kara L.; Viola, Helena M.; Shearwood, Anne-Marie J.; Hool, Livia C.; Rackham, Oliver; Filipovska, Aleksandra

    2015-01-01

    The evolutionary divergence of mitochondrial ribosomes from their bacterial and cytoplasmic ancestors has resulted in reduced RNA content and the acquisition of mitochondria-specific proteins. The mitochondrial ribosomal protein of the small subunit 34 (MRPS34) is a mitochondria-specific ribosomal protein found only in chordates, whose function we investigated in mice carrying a homozygous mutation in the nuclear gene encoding this protein. The Mrps34 mutation causes a significant decrease of this protein, which we show is required for the stability of the 12S rRNA, the small ribosomal subunit and actively translating ribosomes. The synthesis of all 13 mitochondrially-encoded polypeptides is compromised in the mutant mice, resulting in reduced levels of mitochondrial proteins and complexes, which leads to decreased oxygen consumption and respiratory complex activity. The Mrps34 mutation causes tissue-specific molecular changes that result in heterogeneous pathology involving alterations in fractional shortening of the heart and pronounced liver dysfunction that is exacerbated with age. The defects in mitochondrial protein synthesis in the mutant mice are caused by destabilization of the small ribosomal subunit that affects the stability of the mitochondrial ribosome with age. PMID:25816300

  14. Heterochromatin-Mediated Association of Achiasmate Homologs Declines With Age When Cohesion Is Compromised

    PubMed Central

    Subramanian, Vijayalakshmi V.; Bickel, Sharon E.

    2009-01-01

    Normally, meiotic crossovers in conjunction with sister-chromatid cohesion establish a physical connection between homologs that is required for their accurate segregation during the first meiotic division. However, in some organisms an alternative mechanism ensures the proper segregation of bivalents that fail to recombine. In Drosophila oocytes, accurate segregation of achiasmate homologs depends on pairing that is mediated by their centromere-proximal heterochromatin. Our previous work uncovered an unexpected link between sister-chromatid cohesion and the fidelity of achiasmate segregation when Drosophila oocytes are experimentally aged. Here we show that a weak mutation in the meiotic cohesion protein ORD coupled with a reduction in centromere-proximal heterochromatin causes achiasmate chromosomes to missegregate with increased frequency when oocytes undergo aging. If ORD activity is more severely disrupted, achiasmate chromosomes with the normal amount of pericentric heterochromatin exhibit increased nondisjunction when oocytes age. Significantly, even in the absence of aging, a weak ord allele reduces heterochromatin-mediated pairing of achiasmate chromosomes. Our data suggest that sister-chromatid cohesion proteins not only maintain the association of chiasmate homologs but also play a role in promoting the physical association of achiasmate homologs in Drosophila oocytes. In addition, our data support the model that deterioration of meiotic cohesion during the aging process compromises the segregation of achiasmate as well as chiasmate bivalents. PMID:19204374

  15. Bioactive bilayered dressing for compromised epidermal tissue regeneration with sequential activity of complementary agents.

    PubMed

    Reyes-Ortega, Felisa; Cifuentes, Alberto; Rodríguez, Gema; Aguilar, María Rosa; González-Gómez, Álvaro; Solis, Raul; García-Honduvilla, Natalio; Buján, Julia; García-Sanmartin, Josune; Martínez, Alfredo; Román, Julio San

    2015-09-01

    The article deals with the design, preparation, and evaluation of a new bilayered dressing for application in the healing of compromised wounds. The system is based on the sequential release of two complementary bioactive components to enhance the activation of the regeneration of dermal tissue. The internal layer is a highly hydrophilic and biodegradable film of gelatin and hyaluronic acid (HG), crosslinked with the natural compound genipin, which reacts with the amine groups of gelatin. This film is loaded with the proangiogenic, anti-inflammatory, and antibacterial peptide, proadrenomedullin N-terminal 20 peptide (PAMP), that is released slowly in the wound site. The external layer, more stable and less hydrophilic, is constituted by a biodegradable polyurethane derived from poly(caprolactone) and pluronic L61. This layer is loaded with resorbable nanoparticles of bemiparin (a fractionated low molecular weight heparin), which promotes the activation of growth factors, FGF and VEGF, and provides a good biomechanical stability and controlled permeability of the bilayered dressing. Experiments carried out in mice demonstrate the excellent angiogenic effect of the HG film in the dermal tissue. Application of the bilayered dressing in the wound healing rabbit ear model shows an improved cicatrization of the wound in both ischemic and non-ischemic defects, favoring epithelialization and reducing noticeably the contraction and the inflammation. PMID:26022967

  16. Simulated Microgravity Using a Rotary Culture System Compromises the In Vitro Development of Mouse Preantral Follicles

    PubMed Central

    Wu, Yonggen; Lin, Wei; Chen, Zaichong; Meng, Luhe; Liu, Jun; Zhou, Ying

    2016-01-01

    Background Growing cells in simulated weightlessness condition might be a highly promising new technique to maintain or generate tissue constructs in a scaffold-free manner. There is limited evidence that microgravity condition may affect development of ovarian follicles. The objective of the present study was to investigate the effects of simulated microgravity on the in vitro development of mouse preantral follicles. Methods and Results Ovarian tissue from 14-day-old mice, or preantral follicles mechanically isolated from 14-day-old mouse ovaries were cultured at a simulated microgravity condition generated using a rotating wall vessel apparatus. Follicle survival was assessed quantitatively using H&E staining. Follicle diameter and oocyte diameter were measured under an inverted microscope. Ultrastructure of oocytes was evaluated using transmission electron microscopy. We observed that simulated microgravity compromised follicle survival in vitro, downregulated PCNA and GDF-9 expressions, and caused ultrastructural abnormalities in oocytes. Conclusion This study showed for the first time that three-dimensional culture condition generated by simulated microgravity is detrimental to the initial stage development of mouse preantral follicles in vitro. The experimental setup provides a model to further investigate the mechanisms involved in the in vitro developmental processes of oocytes/granulosa cells under the microgravity condition. PMID:26963099

  17. Optimizing Maxillary Aesthetics of a Severe Compromised Tooth through Orthodontic Movement and Dental Implants

    PubMed Central

    de Avila, Erica Dorigatti; Cirelli, Joni Augusto; Cardoso, Mauricio de Almeida; Capelozza-Filho, Leopoldino; Borelli Barros, Luiz Antonio

    2014-01-01

    Treatment of severe compromised tooth in the maxillary anterior area still poses great challenge to the clinicians. Several treatment modalities have been proposed to restore the function and aesthetics in teeth with advanced periodontal disease. The present study aims to report a case of traumatic injury of a left-maxillary central incisor with ridge preservation, orthodontic movement, and implant therapy. A 45-year-old woman underwent the proposed treatment for her left central incisor: basic periodontal therapy, xenogenous bone graft, and guided bone regeneration (GBR). Six months after the graft procedure, orthodontic movement by means of alignment and leveling was made and a coronal displacement of the gingival margin and vertical bone apposition could be observed after 13 months of active movement. Afterwards, a dental implant was placed followed by a connective tissue graft and immediate provisionalization of the crown. In conclusion, orthodontic movement was effective to improve the gingival tissue and alveolar bone prior to implant placement favoring the aesthetic results. Six years postoperatively, the results revealed height and width alveolar bone gain indicating that the treatment proposed was able to restore all the functional and aesthetic parameters. PMID:24523969

  18. Detection of respiratory compromise by acoustic monitoring, capnography, and brain function monitoring during monitored anesthesia care.

    PubMed

    Tanaka, Pedro P; Tanaka, Maria; Drover, David R

    2014-12-01

    Episodes of apnea in sedated patients represent a risk of respiratory compromise. We hypothesized that acoustic monitoring would be equivalent to capnography for detection of respiratory pauses, with fewer false alarms. In addition, we hypothesized that the patient state index (PSI) would be correlated with the frequency of respiratory pauses and therefore could provide information about the risk of apnea during sedation. Patients undergoing sedation for surgical procedures were monitored for respiration rate using acoustic monitoring and capnography and for depth of sedation using the PSI. A clinician blinded to the acoustic and sedation monitor observed the capnograph and patient to assess sedation and episodes of apnea. Another clinician retrospectively reviewed the capnography and acoustic waveform and sound files to identify true positive and false positive respiratory pauses by each method (reference method). Sensitivity, specificity, and likelihood ratio for detection of respiratory pause was calculated for acoustic monitoring and capnography. The correlation of PSI with respiratory pause events was determined. For the 51 respiratory pauses validated by retrospective analysis, the sensitivity, specificity, and likelihood ratio positive for detection were 16, 96 %, and 3.5 for clinician observation; 88, 7 %, and 1.0 for capnography; and 55, 87 %, and 4.1 for acoustic monitoring. There was no correlation between PSI and respiratory pause events. Acoustic monitoring had the highest likelihood ratio positive for detection of respiratory pause events compared with capnography and clinician observation and, therefore, may provide the best method for respiration rate monitoring during these procedures. PMID:24420342

  19. Heavy Cigarette Smokers in a Chinese Population Display a Compromised Permeability Barrier.

    PubMed

    Xin, Shujun; Ye, Li; Man, George; Lv, Chengzhi; Elias, Peter M; Man, Mao-Qiang

    2016-01-01

    Cigarette smoking is associated with various cutaneous disorders with defective permeability. Yet, whether cigarette smoking influences epidermal permeability barrier function is largely unknown. Here, we measured skin biophysical properties, including permeability barrier homeostasis, stratum corneum (SC) integrity, SC hydration, skin surface pH, and skin melanin/erythema index, in cigarette smokers. A total of 99 male volunteers were enrolled in this study. Smokers were categorized as light-to-moderate (<20 cigarettes/day) or heavy smokers (≥20 cigarettes/day). An MPA5 was used to measure SC hydration and skin melanin/erythema index on the dorsal hand, forehead, and cheek. Basal transepidermal water loss (TEWL) and barrier recovery rates were assessed on the forearm. A Skin-pH-Meter pH900 was used to measure skin surface pH. Our results showed that heavy cigarette smokers exhibited delayed barrier recovery after acute abrogation (1.02% ± 13.06 versus 16.48% ± 6.07), and barrier recovery rates correlated negatively with the number of daily cigarettes consumption (p = 0.0087). Changes in biophysical parameters in cigarette smokers varied with body sites. In conclusion, heavy cigarette smokers display compromised permeability barrier homeostasis, which could contribute, in part, to the increased prevalence of certain cutaneous disorders characterized by defective permeability. Thus, improving epidermal permeability barrier should be considered for heavy cigarette smokers. PMID:27437403

  20. Respect in forensic psychiatric nurse-patient relationships: a practical compromise.

    PubMed

    Rose, Donald N; Peter, Elizabeth; Gallop, Ruth; Angus, Jan E; Liaschenko, Joan

    2011-03-01

    The context of forensic psychiatric nursing is distinct from other psychiatric settings as, it involves placement of patients in secure environments with restrictions determined by the courts. Previous literature has identified that nurses morally struggle with respecting patients who have committed heinous offences, which can lead to the patient being depersonalized and dehumanized. Although respect is fundamental to ethical nursing practice, it has not been adequately explored conceptually or empirically. As a result, little knowledge exists that identifies how nurses develop, maintain, and express respect for patients. The purpose of this study is to analyze the concept of respect systematically, from a forensic psychiatric nurse's perspective using the qualitative methodology of focused ethnography. Forensic psychiatric nurses were recruited from two medium secure forensic rehabilitation units. In the first interview, 13 registered nurses (RNs) and two registered practical nurses (RPNs) participated, and although all informants were invited to the second interview, six RNs were lost to follow-up. Despite this loss, saturation was achieved and the data were interpreted through a feminist philosophical lens. Respect was influenced by factors categorized into four themes: (1) emotive-cognitive reactions, (2) nonjudgmental approach, (3) social identity and power, and (4) context. The data from the themes indicate that forensic psychiatric nurses strike a practical compromise, in their understanding and enactment of respect in therapeutic relationships with forensic psychiatric patients. PMID:21348929

  1. Aging-related elevation of sphingoid bases shortens yeast chronological life span by compromising mitochondrial function

    PubMed Central

    Yi, Jae Kyo; Xu, Ruijuan; Jeong, Eunmi; Mileva, Izolda; Truman, Jean-Philip; Lin, Chih-li; Wang, Kai; Snider, Justin; Wen, Sally; Obeid, Lina M.; Hannun, Yusuf A.; Mao, Cungui

    2016-01-01

    Sphingoid bases (SBs) as bioactive sphingolipids, have been implicated in aging in yeast. However, we know neither how SBs are regulated during yeast aging nor how they, in turn, regulate it. Herein, we demonstrate that the yeast alkaline ceramidases (YPC1 and YDC1) and SB kinases (LCB4 and LCB5) cooperate in regulating SBs during the aging process and that SBs shortens chronological life span (CLS) by compromising mitochondrial functions. With a lipidomics approach, we found that SBs were increased in a time-dependent manner during yeast aging. We also demonstrated that among the enzymes known for being responsible for the metabolism of SBs, YPC1 was upregulated whereas LCB4/5 were downregulated in the course of aging. This inverse regulation of YPC1 and LCB4/5 led to the aging-related upregulation of SBs in yeast and a reduction in CLS. With the proteomics-based approach (SILAC), we revealed that increased SBs altered the levels of proteins related to mitochondria. Further mechanistic studies demonstrated that increased SBs inhibited mitochondrial fusion and caused fragmentation, resulting in decreases in mtDNA copy numbers, ATP levels, mitochondrial membrane potentials, and oxygen consumption. Taken together, these results suggest that increased SBs mediate the aging process by impairing mitochondrial structural integrity and functions. PMID:27008706

  2. Gamma processing of Arabic bread for immune system-compromised cancer patients

    SciTech Connect

    Grecz, N.; Brannon, R.; Jaw, R.; Al-Harithy, R.; Hahn, E.W.

    1985-12-01

    Arabic bread prepared from local Saudi flour contained a total of up to 105/sup 4/ organisms per g. Most of these were bacterial spores that survived the baking process (1.3 x 10/sup 2/ to 3.5 x 10/sup 3/) and a small number of yeasts and molds (10 to 40 cells per g). The organisms in Arabic bread appear to be harmless to healthy individuals. However, for immune system-compromised cancer patients and bone marrow transplant recipients, it is prudent to irradiate the bread to reduce microbial contamination. The decimal reduction doses (10% survival) for the most radiation-resistant organisms (spore formers) in bread were 0.11 to 0.15 Mrad. Accordingly, 0.6 Mrad was sufficient to reduce the number of spores in Arabic bread by a factor of 10,000, i.e., to <1/g. This treatment constitutes radiation pasteurization (radicidation), and to this extent, provides a margin of microbiological safety. Sensory evaluation by the nine-point hedonic scale showed no detectable loss of organoleptic quality of bread up to 0.6 Mrad, while irradiation to 2.5 Mrad induced unacceptable organoleptic changes.

  3. Premature Graying as a Consequence of Compromised Antioxidant Activity in Hair Bulb Melanocytes and Their Precursors

    PubMed Central

    Shi, Ying; Luo, Long-Fei; Liu, Xiao-Ming; Zhou, Qiong; Xu, Shi-Zheng; Lei, Tie-Chi

    2014-01-01

    Intricate coordinated mechanisms that govern the synchrony of hair growth and melanin synthesis remain largely unclear. These two events can be uncoupled in prematurely gray hair, probably due to oxidative insults that lead to the death of oxidative stress-sensitive melanocytes. In this study, we examined the gene expression profiles of middle (bulge) and lower (hair bulb) segments that had been micro-dissected from unpigmented and from normally pigmented hair follicles from the same donors using quantitative real-time RT-PCR (qPCR) arrays. We found a significant down-regulation of melanogenesis-related genes (TYR, TYRP1, MITF, PAX3, POMC) in unpigmented hair bulbs and of marker genes typical for melanocyte precursor cells (PAX3, SOX10, DCT) in unpigmented mid-segments compared with their pigmented analogues. qPCR, western blotting and spin trapping assays revealed that catalase protein expression and hydroxyl radical scavenging activities are strongly repressed in unpigmented hair follicles. These data provide the first clear evidence that compromised antioxidant activity in gray hair follicles simultaneously affects mature hair bulb melanocytes and their immature precursor cells in the bulge region. PMID:24695442

  4. Has Blending Compromised Cepheid-based Determinations of the Extragalactic Distance Scale?

    PubMed

    Gibson; Maloney; Sakai

    2000-02-10

    We examine the suggestion that half of the galaxies observed by the Hubble Space Telescope Key Project and the Type Ia Supernova Calibration Team have had their distances systematically underestimated, by 0.1-0.3 mag in the distance modulus, because of the underappreciated influence of stellar profile blending on the Wide Field Camera chips. The signature of such an effect would be a systematic trend in (1) the Type Ia supernova-corrected peak luminosity and (2) the Tully-Fisher residuals, with increasing calibrator distance, and (3) a differential offset between Planetary Camera and Wide Field Camera distance moduli, within the same galaxy. The absence of a trend would be expected if blending were negligible (as has been inherently assumed in the analyses of the aforementioned teams). We adopt a functional form for the predicted influence of blending that is consistent with the models of Mochejska et al. and Stanek & Udalski, and we demonstrate that the expected correlation with distance predicted by these studies is not supported by the data. We conclude that the Cepheid-based extragalactic distance scale has not been severely compromised by the neglect of blending. PMID:10642192

  5. Elevated non-esterified fatty acid concentrations during bovine oocyte maturation compromise early embryo physiology.

    PubMed

    Van Hoeck, Veerle; Sturmey, Roger G; Bermejo-Alvarez, Pablo; Rizos, Dimitrios; Gutierrez-Adan, Alfonso; Leese, Henry J; Bols, Peter E J; Leroy, Jo L M R

    2011-01-01

    Elevated concentrations of serum non-esterified fatty acids (NEFA), associated with maternal disorders such as obesity and type II diabetes, alter the ovarian follicular micro-environment and have been associated with subfertility arising from reduced oocyte developmental competence. We have asked whether elevated NEFA concentrations during oocyte maturation affect the development and physiology of zygotes formed from such oocytes, using the cow as a model. The zygotes were grown to blastocysts, which were evaluated for their quality in terms of cell number, apoptosis, expression of key genes, amino acid turnover and oxidative metabolism. Oocyte maturation under elevated NEFA concentrations resulted in blastocysts with significantly lower cell number, increased apoptotic cell ratio and altered mRNA abundance of DNMT3A, IGF2R and SLC2A1. In addition, the blastocysts displayed reduced oxygen, pyruvate and glucose consumption, up-regulated lactate consumption and higher amino acid metabolism. These data indicate that exposure of maturing oocytes to elevated NEFA concentrations has a negative impact on fertility not only through a reduction in oocyte developmental capacity but through compromised early embryo quality, viability and metabolism. PMID:21858021

  6. Myocardial edema and compromised left ventricular function attributable to dirofilariasis and cardiopulmonary bypass in dogs.

    PubMed

    Rohn, D A; Davis, K L; Mehlhorn, U; Allen, S J; Laine, G A

    1995-02-01

    We investigated the relation between left ventricular dysfunction and myocardial edema in dogs with heartworm (Dirofilaria immitis) infection that were undergoing cardiopulmonary bypass. Dogs with and without D immitis were anesthetized by continuous thiopental infusion and were mechanically ventilated. Sonomicrometry crystals were placed on the long and short axes of the left ventricle, and a Millar pressure transducer was placed in the left ventricular chamber. Pressure-volume loops were digitized and continuously recorded. Dogs with and without D immitis were placed on standard hypothermic cardiopulmonary bypass, with 1 hour of aortic cross-clamp. Wet-to-dry weight ratio corrected for residual blood volume was used to quantitate the volume of myocardial edema. Preload recruitable stroke work was used as a preload-independent index of systolic function. Tau, the isovolumic relaxation time constant, was determined to assess diastolic relaxation. Dogs with D immitis had increased baseline myocardial wet-to-dry weight ratio. After cardiopulmonary bypass, myocardial edema increased in all dogs. Acute edema attributable to cardiopulmonary bypass decreased preload recruitable stroke work in all dogs of both groups, and dogs with D immitis could not be weaned from cardiopulmonary bypass. Myocardial edema increased diastolic relaxation times (tau) in dogs with and without D immitis. We conclude that cardiopulmonary bypass and heartworm infection induce myocardial edema. This edema compromises left ventricular systolic and diastolic function making D immitis an important confounding factor in weaning dogs from cardiopulmonary bypass. PMID:7717590

  7. Compromise-based Robust Prioritization of Climate Change Adaptation Strategies for Watershed Management

    NASA Astrophysics Data System (ADS)

    Kim, Y.; Chung, E. S.

    2014-12-01

    This study suggests a robust prioritization framework for climate change adaptation strategies under multiple climate change scenarios with a case study of selecting sites for reusing treated wastewater (TWW) in a Korean urban watershed. The framework utilizes various multi-criteria decision making techniques, including the VIKOR method and the Shannon entropy-based weights. In this case study, the sustainability of TWW use is quantified with indicator-based approaches with the DPSIR framework, which considers both hydro-environmental and socio-economic aspects of the watershed management. Under the various climate change scenarios, the hydro-environmental responses to reusing TWW in potential alternative sub-watersheds are determined using the Hydrologic Simulation Program in Fortran (HSPF). The socio-economic indicators are obtained from the statistical databases. Sustainability scores for multiple scenarios are estimated individually and then integrated with the proposed approach. At last, the suggested framework allows us to prioritize adaptation strategies in a robust manner with varying levels of compromise between utility-based and regret-based strategies.

  8. Compromised axon initial segment integrity in EAE is preceded by microglial reactivity and contact.

    PubMed

    Clark, Kareem C; Josephson, Anna; Benusa, Savannah D; Hartley, Rebecca K; Baer, Matthew; Thummala, Suneel; Joslyn, Martha; Sword, Brooke A; Elford, Howard; Oh, Unsong; Dilsizoglu-Senol, Aysegul; Lubetzki, Catherine; Davenne, Marc; DeVries, George H; Dupree, Jeffrey L

    2016-07-01

    Axonal pathology is a key contributor to long-term disability in multiple sclerosis (MS), an inflammatory demyelinating disease of the central nervous system (CNS), but the mechanisms that underlie axonal pathology in MS remain elusive. Evidence suggests that axonal pathology is a direct consequence of demyelination, as we and others have shown that the node of Ranvier disassembles following loss of myelin. In contrast to the node of Ranvier, we now show that the axon initial segment (AIS), the axonal domain responsible for action potential initiation, remains intact following cuprizone-induced cortical demyelination. Instead, we find that the AIS is disrupted in the neocortex of mice that develop experimental autoimmune encephalomyelitis (EAE) independent of local demyelination. EAE-induced mice demonstrate profound compromise of AIS integrity with a progressive disruption that corresponds to EAE clinical disease severity and duration, in addition to cortical microglial reactivity. Furthermore, treatment with the drug didox results in attenuation of AIS pathology concomitantly with microglial reversion to a less reactive state. Together, our findings suggest that inflammation, but not demyelination, disrupts AIS integrity and that therapeutic intervention may protect and reverse this pathology. GLIA 2016;64:1190-1209. PMID:27100937

  9. Loss of CARD9-mediated innate activation attenuates severe influenza pneumonia without compromising host viral immunity

    PubMed Central

    Uematsu, Takayuki; Iizasa, Ei’ichi; Kobayashi, Noritada; Yoshida, Hiroki; Hara, Hiromitsu

    2015-01-01

    Influenza virus (IFV) infection is a common cause of severe viral pneumonia associated with acute respiratory distress syndrome (ARDS), which is difficult to control with general immunosuppressive therapy including corticosteroids due to the unfavorable effect on viral replication. Studies have suggested that the excessive activation of the innate immunity by IFV is responsible for severe pathologies. In this study, we focused on CARD9, a signaling adaptor known to regulate innate immune activation through multiple innate sensor proteins, and investigated its role in anti-IFV defense and lung pathogenesis in a mouse model recapitulating severe influenza pneumonia with ARDS. We found that influenza pneumonia was dramatically attenuated in Card9-deficient mice, which showed improved mortality with reduced inflammatory cytokines and chemokines in the infected lungs. However, viral clearance, type-I interferon production, and the development of anti-viral B and T cell immunity were not compromised by CARD9 deficiency. Syk or CARD9-deficient DCs but not macrophages showed impaired cytokine but not type-I interferon production in response to IFV in vitro, indicating a possible role for the Syk-CARD9 pathway in DCs in excessive inflammation of IFV-infected lungs. Therefore, inhibition of this pathway is an ideal therapeutic target for severe influenza pneumonia without affecting viral clearance. PMID:26627732

  10. Enamel-smear compromises bonding by mild self-etch adhesives.

    PubMed

    Mine, A; De Munck, J; Vivan Cardoso, M; Van Landuyt, K L; Poitevin, A; Kuboki, T; Yoshida, Y; Suzuki, K; Van Meerbeek, B

    2010-12-01

    In light of the increased popularity of less acidic, so-called 'ultra-mild' self-etch adhesives, adhesion to enamel is becoming more critical. It is hypothesized that this compromised enamel bonding should, to a certain extent, be attributed to interference of bur debris smeared across enamel during cavity preparation. High-resolution transmission electron microscopy revealed that the enamel smear layer differed not only in thickness, but also in crystal density and size, depending on the surface-preparation method used. Lab-demineralization of sections clearly disclosed that resin-infiltration of an ultra-mild self-etch adhesive progressed preferentially along micro-cracks that were abundantly present at and underneath the bur-cut enamel surface. The surface-preparation method significantly affected the nature of the smear layer and the interaction with the ultra-mild adhesive, being more uniform and dense for a lab-SiC-prepared surface vs. a clinically relevant bur-prepared surface. PMID:20929718

  11. 3-bromopyruvate inhibits glycolysis, depletes cellular glutathione, and compromises the viability of cultured primary rat astrocytes.

    PubMed

    Ehrke, Eric; Arend, Christian; Dringen, Ralf

    2015-07-01

    The pyruvate analogue 3-bromopyruvate (3-BP) is an electrophilic alkylator that is considered a promising anticancer drug because it has been shown to kill cancer cells efficiently while having little toxic effect on nontumor cells. To test for potential adverse effects of 3-BP on brain cells, we exposed cultured primary rat astrocytes to 3-BP and investigated the effects of this compound on cell viability, glucose metabolism, and glutathione (GSH) content. The presence of 3-BP severely compromised cell viability and slowed cellular glucose consumption and lactate production in a time- and concentration-dependent manner, with half-maximal effects observed at about 100 µM 3-BP after 4 hr of incubation. The cellular hexokinase activity was not affected in 3-BP-treated astrocytes, whereas within 30 min after application of 3-BP the activity of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was inhibited, and cellular GSH content was depleted in a concentration-dependent manner, with half-maximal effects observed at about 30 µM 3-BP. The depletion of cellular GSH after exposure to 100 µM 3-BP was not prevented by the presence of 10 mM of the monocarboxylates lactate or pyruvate, suggesting that 3-BP is not taken up into astrocytes predominantly by monocarboxylate transporters. The data suggest that inhibition of glycolysis by inactivation of GAPDH and GSH depletion contributes to the toxicity that was observed for 3-BP-treated cultured astrocytes. PMID:25196479

  12. High incarceration rates among black men enrolled in clinical studies may compromise ability to identify disparities.

    PubMed

    Wang, Emily A; Aminawung, Jenerius A; Wildeman, Christopher; Ross, Joseph S; Krumholz, Harlan M

    2014-05-01

    In 1978 the federal government restricted research on prison and jail inmates in medical studies, the result of decades of unethical research in correctional institutions. We evaluated the impact this policy has had on studies of health outcomes in minority populations, particularly studies involving black men, who are disproportionately incarcerated. Specifically, we explored the effect of incarceration on follow-up rates of fourteen prospective clinical studies funded by the National Heart, Lung, and Blood Institute. We estimated that during the past three decades high rates of incarceration of black men may have accounted for up to 65 percent of the loss to follow-up among black men in these studies. The impact of incarceration was far less among white men, black women, and white women. These estimates suggest that the ability of those studies to examine racial disparities in health outcomes, as well as to understand the experience of this group, could be compromised. We believe that community-recruited subjects who are incarcerated should be allowed to continue participating in observational clinical research that poses minimal risk to participants. PMID:24799583

  13. Heavy Cigarette Smokers in a Chinese Population Display a Compromised Permeability Barrier

    PubMed Central

    Xin, Shujun; Ye, Li; Lv, Chengzhi; Elias, Peter M.

    2016-01-01

    Cigarette smoking is associated with various cutaneous disorders with defective permeability. Yet, whether cigarette smoking influences epidermal permeability barrier function is largely unknown. Here, we measured skin biophysical properties, including permeability barrier homeostasis, stratum corneum (SC) integrity, SC hydration, skin surface pH, and skin melanin/erythema index, in cigarette smokers. A total of 99 male volunteers were enrolled in this study. Smokers were categorized as light-to-moderate (<20 cigarettes/day) or heavy smokers (≥20 cigarettes/day). An MPA5 was used to measure SC hydration and skin melanin/erythema index on the dorsal hand, forehead, and cheek. Basal transepidermal water loss (TEWL) and barrier recovery rates were assessed on the forearm. A Skin-pH-Meter pH900 was used to measure skin surface pH. Our results showed that heavy cigarette smokers exhibited delayed barrier recovery after acute abrogation (1.02% ± 13.06 versus 16.48% ± 6.07), and barrier recovery rates correlated negatively with the number of daily cigarettes consumption (p = 0.0087). Changes in biophysical parameters in cigarette smokers varied with body sites. In conclusion, heavy cigarette smokers display compromised permeability barrier homeostasis, which could contribute, in part, to the increased prevalence of certain cutaneous disorders characterized by defective permeability. Thus, improving epidermal permeability barrier should be considered for heavy cigarette smokers. PMID:27437403

  14. Knowledge, attitudes and practices of secondary-school pupils in Oman: I. health-compromising behaviours.

    PubMed

    Jaffer, Y A; Afifi, M; Al Ajmi, F; Alouhaishi, K

    2006-01-01

    We investigated the practice of some of health-compromising behaviours among Omani adolescents and their correlates in a nationally representative secondary school-based sample of 1670 boys and 1675 girls. The mean age of the sample was 17.13 (SD 1.35) years. Through a self-administrated questionnaire the adolescents were asked about 6 risky behaviours: current smoking, ever use of alcohol, succumbing to peer pressure to take illicit drugs, driving without a licence, speeding while driving and being involved in a physical fight in the month prior to the survey. Demographic and psychosocial variables related to their risk behaviours were also assessed. The results indicated that 4.6 % were current smokers, 4.3% had drunk alcohol and 4.6% had taken drugs. About 20% had been involved in a physical fight in the month prior to the survey, 33.4% drove without a licence and 33.9% liked to speed. Male sex and low self-esteem were the strongest predictors of risky behaviour. PMID:17037220

  15. Umami Increases Consumer Acceptability, and Perception of Sensory and Emotional Benefits without Compromising Health Benefit Perception.

    PubMed

    Miyaki, Takashi; Retiveau-Krogmann, Annlyse; Byrnes, Erin; Takehana, Shunji

    2016-02-01

    This study was undertaken to understand how consumers in the United States perceive umami-rich products, specifically low sodium chicken noodle soup. Results suggest that the addition of monosodium l-glutamate (MSG) at a concentration of 0.1% to 0.5%, alone or in synergy with 5'-ribonucleotides of inosine monophosphate (IMP) at 0.1% not only increases consumer acceptance but also positively impacts other aspects of consumer perception. Regardless of concentration of MSG and IMP, samples enhanced in umami compounds were perceived as more savory, flavorful, and less bland while providing a more homemade, fresh, and healthy wholesome taste than a control sample. From a functional and emotional benefit standpoint, when consuming umami-rich samples, consumers reported feeling significantly higher general satisfaction (they felt more content, relaxed, satisfied, less disappointed, dissatisfied…) and heightened positive emotions (happy, excited, indulgent…) than under the control condition. The feeling of being healthy while consuming the dish was not compromised. Last, when asked how they would feel if serving the soup sample to their family or friends, consumers projected feeling more positively under the umami-rich conditions (more happy, competent, loving, less dissatisfied or disappointed) compared to the control condition. PMID:26720057

  16. Dopamine release is severely compromised in the R6/2 mouse model of Huntington's disease.

    PubMed

    Johnson, Michael A; Rajan, Vignesh; Miller, Charles E; Wightman, R Mark

    2006-05-01

    Recently, alterations in dopamine signaling have been implicated in Huntington's disease. In this work, dopamine release and uptake was measured in striatal slices from the R6/2 transgenic mouse model of Huntington's disease using fast-scan cyclic voltammetry at carbon-fiber microelectrodes. Dopamine release in brain slices from 6-week-old R6/2 mice is substantially reduced (53% of wild type), while dopamine uptake is unaffected. In agreement with this, R6/2 mice injected with the dopamine uptake inhibitor cocaine exhibited a blunted motor activity response (54% of wild type). At 10 weeks of age, an even more dramatic motor activity decrease in response to cocaine injection (21% of wild type) was observed. Moreover, the pre-drug activity of 10-week-old R6/2 mice was significantly reduced (by 37%) compared with 6-week-old R6/2 mice. Striatal dopamine release decreased with age, indicating that progressive alterations in dopaminergic pathways may affect motor activity. The inhibition constants of cocaine and methamphetamine (METH) determined in brain slices differed little between genotype or age group, suggesting that the decreased responses to cocaine and METH arise from compromised dopamine release rather than differences in uptake or drug action. Collectively, these data demonstrate (i) a reduction in the ability of dopamine terminals to release dopamine and (ii) the importance of this attenuation of release on the motor symptoms of Huntington's disease. PMID:16573654

  17. SEMA4D compromises blood-brain barrier, activates microglia, and inhibits remyelination in neurodegenerative disease.

    PubMed

    Smith, Ernest S; Jonason, Alan; Reilly, Christine; Veeraraghavan, Janaki; Fisher, Terrence; Doherty, Michael; Klimatcheva, Ekaterina; Mallow, Crystal; Cornelius, Chad; Leonard, John E; Marchi, Nicola; Janigro, Damir; Argaw, Azeb Tadesse; Pham, Trinh; Seils, Jennifer; Bussler, Holm; Torno, Sebold; Kirk, Renee; Howell, Alan; Evans, Elizabeth E; Paris, Mark; Bowers, William J; John, Gareth; Zauderer, Maurice

    2015-01-01

    Multiple sclerosis (MS) is a chronic neuroinflammatory disease characterized by immune cell infiltration of CNS, blood-brain barrier (BBB) breakdown, localized myelin destruction, and progressive neuronal degeneration. There exists a significant need to identify novel therapeutic targets and strategies that effectively and safely disrupt and even reverse disease pathophysiology. Signaling cascades initiated by semaphorin 4D (SEMA4D) induce glial activation, neuronal process collapse, inhibit migration and differentiation of oligodendrocyte precursor cells (OPCs), and disrupt endothelial tight junctions forming the BBB. To target SEMA4D, we generated a monoclonal antibody that recognizes mouse, rat, monkey and human SEMA4D with high affinity and blocks interaction between SEMA4D and its cognate receptors. In vitro, anti-SEMA4D reverses the inhibitory effects of recombinant SEMA4D on OPC survival and differentiation. In vivo, anti-SEMA4D significantly attenuates experimental autoimmune encephalomyelitis in multiple rodent models by preserving BBB integrity and axonal myelination and can be shown to promote migration of OPC to the site of lesions and improve myelin status following chemically-induced demyelination. Our study underscores SEMA4D as a key factor in CNS disease and supports the further development of antibody-based inhibition of SEMA4D as a novel therapeutic strategy for MS and other neurologic diseases with evidence of demyelination and/or compromise to the neurovascular unit. PMID:25461192

  18. Neural Evidence for Compromised Motor Imagery in Right Hemiparetic Cerebral Palsy

    PubMed Central

    van Elk, Michiel; Crajé, Celine; Beeren, Manuela E. G. V.; Steenbergen, Bert; van Schie, Hein T.; Bekkering, Harold

    2010-01-01

    In the present event-related potential (ERP) study we investigated the neural and temporal dynamics of motor imagery in participants with right-sided hemiparetic cerebral palsy (HCP; n = 10) and in left-handed control participants (n = 10). A mental rotation task was used in which participants were required to judge the laterality of hand pictures. At a behavioral level participants with HCP were slower in making hand laterality judgments compared to control subjects, especially when presented with pictures representing the affected hand. At a neural level, individuals with HCP were characterized by a reduced rotation-related negativity (RRN) over parietal areas, that was delayed in onset with respect to control participants. Interestingly, participants that were relatively mildly impaired showed a stronger RRN for the rotation of right-hand stimuli than participants that were more strongly impaired in their motor function, suggesting a direct relation between the motor imagery process and the biomechanical constraints of the participant. Together, the results provide new insights in the relation between motor imagery and motor capabilities and indicate that participants with HCP may be characterized by a compromised ability to use motor imagery. PMID:21206766

  19. Canadian Association of Gastroenterology Indicators of Safety Compromise following Colonoscopy in Clinical Practice.

    PubMed

    Borgaonkar, Mark R; Pace, David; Lougheed, Muna; Marcoux, Curtis; Evans, Bradley; Hickey, Nikita; O'Leary, Meghan; McGrath, Jerry

    2016-01-01

    In 2012 the Canadian Association of Gastroenterology published 19 indicators of safety compromise. We studied the incidence of these indicators by reviewing all colonoscopies performed in St. John's, NL, between January 1, 2012, and June 30, 2012. Results. A total of 3235 colonoscopies were included. Adverse events are as follows. Medication-related includes use of reversal agents 0.1%, hypoxia 9.9%, hypotension 15.4%, and hypertension 0.9%. No patients required CPR or experienced allergic reactions or laryngospasm/bronchospasm. The indicator, "sedation dosages in patients older than 70," showed lower usage of fentanyl and midazolam in elderly patients. Procedure-related immediate includes perforation 0.2%, immediate postpolypectomy bleeding 0.3%, need for hospital admission or transfer to the emergency department 0.1%, and severe persistent abdominal pain proven not to be perforation 0.4%. Instrument impaction was not seen. Procedure-related delayed includes death within 14 days 0.1%, unplanned health care visit within 14 days of the colonoscopy 1.8%, unplanned hospitalization within 14 days of the colonoscopy 0.6%, bleeding within 14 days of colonoscopy 0.2%, infection 0.03%, and metabolic complication 0.03%. Conclusions. The most common adverse events were mild and sedation related. Rates of serious adverse events were in keeping with published reports. PMID:27446832

  20. Canadian Association of Gastroenterology Indicators of Safety Compromise following Colonoscopy in Clinical Practice

    PubMed Central

    Borgaonkar, Mark R.; Pace, David; Lougheed, Muna; Marcoux, Curtis; Evans, Bradley; Hickey, Nikita; O'Leary, Meghan; McGrath, Jerry

    2016-01-01

    In 2012 the Canadian Association of Gastroenterology published 19 indicators of safety compromise. We studied the incidence of these indicators by reviewing all colonoscopies performed in St. John's, NL, between January 1, 2012, and June 30, 2012. Results. A total of 3235 colonoscopies were included. Adverse events are as follows. Medication-related includes use of reversal agents 0.1%, hypoxia 9.9%, hypotension 15.4%, and hypertension 0.9%. No patients required CPR or experienced allergic reactions or laryngospasm/bronchospasm. The indicator, “sedation dosages in patients older than 70,” showed lower usage of fentanyl and midazolam in elderly patients. Procedure-related immediate includes perforation 0.2%, immediate postpolypectomy bleeding 0.3%, need for hospital admission or transfer to the emergency department 0.1%, and severe persistent abdominal pain proven not to be perforation 0.4%. Instrument impaction was not seen. Procedure-related delayed includes death within 14 days 0.1%, unplanned health care visit within 14 days of the colonoscopy 1.8%, unplanned hospitalization within 14 days of the colonoscopy 0.6%, bleeding within 14 days of colonoscopy 0.2%, infection 0.03%, and metabolic complication 0.03%. Conclusions. The most common adverse events were mild and sedation related. Rates of serious adverse events were in keeping with published reports. PMID:27446832

  1. Intra- and Inter-Individual Variability in Location Data for Two U.S. Health-Compromised Elderly Cohorts

    EPA Science Inventory

    This study provides descriptive statistical data on daily time spent in three locations of exposure assessment interest for two panel studies of health-compromised elderly individuals > 65 y old having multi-days of human activity data. The panel studies include individuals livi...

  2. 34 CFR 30.70 - How does the Secretary exercise discretion to compromise a debt or to suspend or terminate...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... standards in the FCCS, 4 CFR part 103, to determine whether compromise of a debt is appropriate if— (1) The... standards in the FCCS, 4 CFR part 104, to determine whether suspension or termination of collection action... 34 Education 1 2012-07-01 2012-07-01 false How does the Secretary exercise discretion...

  3. 34 CFR 30.70 - How does the Secretary exercise discretion to compromise a debt or to suspend or terminate...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... standards in the FCCS, 4 CFR part 103, to determine whether compromise of a debt is appropriate if— (1) The... standards in the FCCS, 4 CFR part 104, to determine whether suspension or termination of collection action... 34 Education 1 2011-07-01 2011-07-01 false How does the Secretary exercise discretion...

  4. 34 CFR 30.70 - How does the Secretary exercise discretion to compromise a debt or to suspend or terminate...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... standards in the FCCS, 4 CFR part 103, to determine whether compromise of a debt is appropriate if— (1) The... standards in the FCCS, 4 CFR part 104, to determine whether suspension or termination of collection action... 34 Education 1 2010-07-01 2010-07-01 false How does the Secretary exercise discretion...

  5. 22 CFR 511.6 - Board authority to adjust, determine, compromise, and settle claims and limitations upon that...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... settle claims asserted under the provisions of section 2672 of the Act and under this part. (b) Limitation on Board authority: An award, compromise, or settlement of a claim by the Board under the provisions of section 2672 of the Act, in excess of $25,000, shall be effected only with the prior...

  6. Left Ventricular Gene Expression Profile of Healthy and Cardiovascular Compromised Rat Models Used in Air Pollution Studies

    EPA Science Inventory

    The link between pollutant exposure and cardiovascular disease (CVD) has prompted mechanistic research with animal models of CVD. We hypothesized that the cardiac gene expression patterns of healthy and genetically compromised, CVD-prone rat models, with or without metabolic impa...

  7. Tract-Specific Analyses of Diffusion Tensor Imaging Show Widespread White Matter Compromise in Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Shukla, Dinesh K.; Keehn, Brandon; Muller, Ralph-Axel

    2011-01-01

    Background: Previous diffusion tensor imaging (DTI) studies have shown white matter compromise in children and adults with autism spectrum disorder (ASD), which may relate to reduced connectivity and impaired function of distributed networks. However, tract-specific evidence remains limited in ASD. We applied tract-based spatial statistics (TBSS)…

  8. Conspiracies and Test Compromise: An Evaluation of the Resistance of Test Systems to Small-Scale Cheating

    ERIC Educational Resources Information Center

    Guo, Jing; Tay, Louis; Drasgow, Fritz

    2009-01-01

    Test compromise is a concern in cognitive ability testing because such tests are widely used in employee selection and administered on a continuous basis. In this study, the resistance of cognitive tests, deployed in different test systems, to small-scale cheating conspiracies, was evaluated regarding the accuracy of ability estimation.…

  9. Accomplishments and Compromises in Prediction Research for World Records and Best Performances in Track and Field and Swimming

    ERIC Educational Resources Information Center

    Liu, Yuanlong; Paul, Stanley; Fu, Frank H.

    2012-01-01

    The conductors of this study reviewed prediction research and studied the accomplishments and compromises in predicting world records and best performances in track and field and swimming. The results of the study showed that prediction research only promises to describe the historical trends in track and field and swimming performances, to study…

  10. Representational and Executive Selection Resources in "Theory of Mind": Evidence from Compromised Belief-Desire Reasoning in Old Age

    ERIC Educational Resources Information Center

    German, Tim P.; Hehman, Jessica A.

    2006-01-01

    Effective belief-desire reasoning requires both specialized representational capacities--the capacity to represent the mental states as such--as well as executive selection processes for accurate performance on tasks requiring the prediction and explanation of the actions of social agents. Compromised belief-desire reasoning in a given population…

  11. The Life Attitudes Schedule: A Theoretically Derived Scale To Assess Adolescent Life-Enhancing, Life-Compromising, and Suicidal Behaviors.

    ERIC Educational Resources Information Center

    Lewinsohn, Peter; And Others

    Adolescent engagement in risk-taking and life-compromising behaviors has become a public health concern. This paper describes the development of three alternate forms of a new scale to measure suicidal and risk-taking behavior, the Life Attitudes Schedule (LAS). The LAS, which was developed and piloted on 1,539 high-school students and young…

  12. 34 CFR 30.70 - How does the Secretary exercise discretion to compromise a debt or to suspend or terminate...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... standards in the FCCS, 4 CFR part 103, to determine whether compromise of a debt is appropriate if— (1) The... standards in the FCCS, 4 CFR part 104, to determine whether suspension or termination of collection action... 34 Education 1 2013-07-01 2013-07-01 false How does the Secretary exercise discretion...

  13. 42 CFR 411.47 - Apportionment of a lump-sum compromise settlement of a workers' compensation claim.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 2 2011-10-01 2011-10-01 false Apportionment of a lump-sum compromise settlement of a workers' compensation claim. 411.47 Section 411.47 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM EXCLUSIONS FROM MEDICARE AND LIMITATIONS ON MEDICARE PAYMENT Limitations...

  14. 42 CFR 411.47 - Apportionment of a lump-sum compromise settlement of a workers' compensation claim.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... of a workers' compensation claim. 411.47 Section 411.47 Public Health CENTERS FOR MEDICARE & MEDICAID... ON MEDICARE PAYMENT Limitations on Medicare Payment for Services Covered Under Workers' Compensation § 411.47 Apportionment of a lump-sum compromise settlement of a workers' compensation claim....

  15. 42 CFR 411.47 - Apportionment of a lump-sum compromise settlement of a workers' compensation claim.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 2 2014-10-01 2014-10-01 false Apportionment of a lump-sum compromise settlement of a workers' compensation claim. 411.47 Section 411.47 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM EXCLUSIONS FROM MEDICARE AND LIMITATIONS ON MEDICARE PAYMENT Limitations...

  16. 42 CFR 411.47 - Apportionment of a lump-sum compromise settlement of a workers' compensation claim.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... of a workers' compensation claim. 411.47 Section 411.47 Public Health CENTERS FOR MEDICARE & MEDICAID... ON MEDICARE PAYMENT Limitations on Medicare Payment for Services Covered Under Workers' Compensation § 411.47 Apportionment of a lump-sum compromise settlement of a workers' compensation claim....

  17. 42 CFR 411.47 - Apportionment of a lump-sum compromise settlement of a workers' compensation claim.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... of a workers' compensation claim. 411.47 Section 411.47 Public Health CENTERS FOR MEDICARE & MEDICAID... ON MEDICARE PAYMENT Limitations on Medicare Payment for Services Covered Under Workers' Compensation § 411.47 Apportionment of a lump-sum compromise settlement of a workers' compensation claim....

  18. Towards A Theory of Autonomous Reconstitution of Compromised Cyber-Systems

    SciTech Connect

    Ramuhalli, Pradeep; Halappanavar, Mahantesh; Coble, Jamie B.; Dixit, Mukul

    2013-11-12

    The ability to maintain mission-critical operations in cyber-systems in the face of disruptions is critical. Faults in cyber systems can come from accidental sources (e.g., natural failure of a component) or deliberate sources (e.g., an intelligent adversary). Natural and intentional manipulation of data, computing, or coordination are the most impactful ways that an attacker can prevent an infrastructure from realizing its mission goals. Under these conditions, the ability to reconstitute critical infrastructure becomes important. Specifically, the question is: Given an intelligent adversary, how can cyber systems respond to keep critical infrastructure operational? In cyber systems, the distributed nature of the system poses serious difficulties in maintaining operations, in part due to the fact that a centralized command and control apparatus is unlikely to provide a robust framework for resilience. Resilience in cyber-systems, in general, has several components, and requires the ability to anticipate and withstand attacks or faults, as well as recover from faults and evolve the system to improve future resilience. The recovery effort (and any subsequent evolution) may require significant reconfiguration of the system (at all levels – hardware, software, services, permissions, etc.) if the system is to be made resilient to further attack or faults. This is especially important in the case of ongoing attacks, where reconfiguration decisions must be taken with care to avoid further compromising the system while maintaining continuity of operations. Collectively, we will label this recovery and evolution process as “reconstitution”. Currently, reconstitution is performed manually, generally after-the-fact, and usually consists of either standing up redundant systems, check-points (rolling back the configuration to a “clean” state), or re-creating the system using “gold-standard” copies. For enterprise systems, such reconstitution may be performed

  19. Compromised Optic Nerve Blood Flow and Autoregulation Secondary to Neural Degeneration

    PubMed Central

    Cull, Grant; Told, Reinhard; Burgoyne, Claude F.; Thompson, Simon; Fortune, Brad; Wang, Lin

    2015-01-01

    Purpose To test the hypothesis that optic nerve head (ONH) blood flow (BF) and autoregulation compromise are consequences of optic nerve degeneration induced by surgical optic nerve transection (ONT). Methods In both eyes of five nonhuman primates, peripapillary retinal nerve fiber layer thickness (RNFLT) was measured by spectral-domain optical coherence tomography. Optic nerve head BF and dynamic autoregulation responses to a rapid manometric IOP increase (from 10–40 mm Hg) were measured by Laser Speckle Flowgraphy. The measurements were conducted every 10 to 15 days before and after unilateral ONT. Post-ONT measurements were repeated until RNFLT in the ONT eye was reduced by more than 40% of baseline value. Results After ONT, RNFLT, and ONH BF progressively declined over time (P < 0.0001 and P = 0.02, respectively). Longitudinal changes between the two were highly correlated (P < 0.0001). When data was grouped by test session, the first significant decreases for RNFLT and BF were found 13 ± 0.8 and 24 ± 3.2 days post ONT, respectively (P < 0.05, both). At the final time point (55 ± 0.5 days post ONT), RNFLT, and BF were reduced by 44% ± 2.0% and 38 ± 5.0% from baseline, respectively. Dynamic autoregulation analysis showed marginal increased response time in post-ONT eyes (P = 0.05). Control eyes showed no longitudinal changes for any parameter. Conclusions The close association between RNFLT loss and ONH BF decrease following optic nerve degeneration demonstrated a clear cause and effect relationship. Increased BF response time appears to be a sign of dynamic autoregulation dysfunction in this ONT model. PMID:26551332

  20. Foxi3 Deficiency Compromises Hair Follicle Stem Cell Specification and Activation.

    PubMed

    Shirokova, Vera; Biggs, Leah C; Jussila, Maria; Ohyama, Takahiro; Groves, Andrew K; Mikkola, Marja L

    2016-07-01

    The hair follicle is an ideal system to study stem cell specification and homeostasis due to its well characterized morphogenesis and stereotypic cycles of stem cell activation upon each hair cycle to produce a new hair shaft. The adult hair follicle stem cell niche consists of two distinct populations, the bulge and the more activation-prone secondary hair germ (HG). Hair follicle stem cells are set aside during early stages of morphogenesis. This process is known to depend on the Sox9 transcription factor, but otherwise the establishment of the hair follicle stem cell niche is poorly understood. Here, we show that that mutation of Foxi3, a Forkhead family transcription factor mutated in several hairless dog breeds, compromises stem cell specification. Further, loss of Foxi3 impedes hair follicle downgrowth and progression of the hair cycle. Genome-wide profiling revealed a number of downstream effectors of Foxi3 including transcription factors with a recognized function in hair follicle stem cells such as Lhx2, Runx1, and Nfatc1, suggesting that the Foxi3 mutant phenotype results from simultaneous downregulation of several stem cell signature genes. We show that Foxi3 displays a highly dynamic expression pattern during hair morphogenesis and cycling, and identify Foxi3 as a novel secondary HG marker. Absence of Foxi3 results in poor hair regeneration upon hair plucking, and a sparse fur phenotype in unperturbed mice that exacerbates with age, caused by impaired secondary HG activation leading to progressive depletion of stem cells. Thus, Foxi3 regulates multiple aspects of hair follicle development and homeostasis. Stem Cells 2016;34:1896-1908. PMID:26992132

  1. Extracellular zinc competitively inhibits manganese uptake and compromises oxidative stress management in Streptococcus pneumoniae.

    PubMed

    Eijkelkamp, Bart A; Morey, Jacqueline R; Ween, Miranda P; Ong, Cheryl-lynn Y; McEwan, Alastair G; Paton, James C; McDevitt, Christopher A

    2014-01-01

    Streptococcus pneumoniae requires manganese for colonization of the human host, but the underlying molecular basis for this requirement has not been elucidated. Recently, it was shown that zinc could compromise manganese uptake and that zinc levels increased during infection by S. pneumoniae in all the niches that it colonized. Here we show, by quantitative means, that extracellular zinc acts in a dose dependent manner to competitively inhibit manganese uptake by S. pneumoniae, with an EC50 of 30.2 µM for zinc in cation-defined media. By exploiting the ability to directly manipulate S. pneumoniae accumulation of manganese, we analyzed the connection between manganese and superoxide dismutase (SodA), a primary source of protection for S. pneumoniae against oxidative stress. We show that manganese starvation led to a decrease in sodA transcription indicating that expression of sodA was regulated through an unknown manganese responsive pathway. Intriguingly, examination of recombinant SodA revealed that the enzyme was potentially a cambialistic superoxide dismutase with an iron/manganese cofactor. SodA was also shown to provide the majority of protection against oxidative stress as a S. pneumoniae ΔsodA mutant strain was found to be hypersensitive to oxidative stress, despite having wild-type manganese levels, indicating that the metal ion alone was not sufficiently protective. Collectively, these results provide a quantitative assessment of the competitive effect of zinc upon manganese uptake and provide a molecular basis for how extracellular zinc exerts a 'toxic' effect on bacterial pathogens, such as S. pneumoniae. PMID:24558498

  2. Conditionally Immortalized Mouse Embryonic Fibroblasts Retain Proliferative Activity without Compromising Multipotent Differentiation Potential

    PubMed Central

    Huang, Enyi; Bi, Yang; Jiang, Wei; Luo, Xiaoji; Yang, Ke; Gao, Jian-Li; Gao, Yanhong; Luo, Qing; Shi, Qiong; Kim, Stephanie H.; Liu, Xing; Li, Mi; Hu, Ning; Liu, Hong; Cui, Jing; Zhang, Wenwen; Li, Ruidong; Chen, Xiang; Shen, Jikun; Kong, Yuhan; Zhang, Jiye; Wang, Jinhua; Luo, Jinyong; He, Bai-Cheng; Wang, Huicong; Reid, Russell R.; Luu, Hue H.; Haydon, Rex C.; Yang, Li; He, Tong-Chuan

    2012-01-01

    Mesenchymal stem cells (MSCs) are multipotent cells which reside in many tissues and can give rise to multiple lineages including bone, cartilage and adipose. Although MSCs have attracted significant attention for basic and translational research, primary MSCs have limited life span in culture which hampers MSCs' broader applications. Here, we investigate if mouse mesenchymal progenitors can be conditionally immortalized with SV40 large T antigen and maintain long-term cell proliferation without compromising their multipotency. Using the system which expresses SV40 large T antigen flanked with Cre/loxP sites, we demonstrate that mouse embryonic fibroblasts (MEFs) can be efficiently immortalized by SV40 large T antigen. The conditionally immortalized MEFs (iMEFs) exhibit an enhanced proliferative activity and maintain long-term cell proliferation, which can be reversed by Cre recombinase. The iMEFs express most MSC markers and retain multipotency as they can differentiate into osteogenic, chondrogenic and adipogenic lineages under appropriate differentiation conditions in vitro and in vivo. The removal of SV40 large T reduces the differentiation potential of iMEFs possibly due to the decreased progenitor expansion. Furthermore, the iMEFs are apparently not tumorigenic when they are subcutaneously injected into athymic nude mice. Thus, the conditionally immortalized iMEFs not only maintain long-term cell proliferation but also retain the ability to differentiate into multiple lineages. Our results suggest that the reversible immortalization strategy using SV40 large T antigen may be an efficient and safe approach to establishing long-term cell culture of primary mesenchymal progenitors for basic and translational research, as well as for potential clinical applications. PMID:22384246

  3. High stability of microRNAs in tissue samples of compromised quality.

    PubMed

    Peiró-Chova, Lorena; Peña-Chilet, María; López-Guerrero, José Antonio; García-Giménez, José Luis; Alonso-Yuste, Elisa; Burgues, Octavio; Lluch, Ana; Ferrer-Lozano, Jaime; Ribas, Gloria

    2013-12-01

    Degradation of tissue samples limits performing RNA-based molecular studies, but little is known about the potential usefulness of samples of compromised quality for studies focused on miRNAs. In this work we analyze a series of cryopreserved tissue samples (n = 14), frozen samples that underwent a severe thawing process (n = 10), and their paired formalin-fixed paraffin-embedded (FFPE) tissue samples (n = 24) from patients with breast cancer obtained during primary surgical resection and collected in 2011. Quality and integrity analyses of the total and small fraction of RNA were carried out. Recovery of specific RNA molecules (miRNAs hsa-miR-21, hsa-miR-125b, and hsa-miR-191; snoRNA RNU6B; and mRNAs GAPDH and HPRT1) was also analyzed by quantitative RT-PCR. Our results suggest that visualisation of the small RNA electrophoretic profiles obtained using the Agilent 2100 bioanalyzer makes it possible to differentiate between the three groups of samples (optimally frozen, thawed, and FFPE). We demonstrate that specific miRNA molecules can be similarly recovered from different tissue sample sources, which supports their high degree of stability. We conclude that miRNAs are robustly detected irrespective of the quality of the tissue sample. In this regard, a word of caution should be raised before degraded samples are discarded: although prior quality assessment of the biological material to be analyzed is recommended, our work demonstrates that degraded tissue samples are also suitable for miRNA studies. PMID:24197449

  4. Cigarette Smoke Exposure Exacerbates Lung Inflammation and Compromises Immunity to Bacterial Infection

    PubMed Central

    Lugade, Amit A.; Bogner, Paul N.; Thatcher, Thomas H.; Sime, Patricia J.; Phipps, Richard P.; Thanavala, Yasmin

    2014-01-01

    The detrimental impact of tobacco on human health is clearly recognized and despite aggressive efforts to prevent smoking, close to one billion individuals worldwide continue to smoke. People with chronic obstructive pulmonary disease (COPD) are susceptible to recurrent respiratory infections with pathogens, including non-typeable Haemophilus influenzae (NTHI), yet the reasons for this increased susceptibility are poorly understood. As mortality rapidly increases with multiple exacerbations, development of protective immunity is critical to improving patient survival. Acute NTHI infection has been studied in the context of cigarette smoke exposure, but this is the first study to investigate chronic infection and the generation of adaptive immune responses to NTHI following chronic smoke exposure. After chronic NTHI infection, mice that had previously been exposed to cigarette smoke developed increased lung inflammation and compromised adaptive immunity relative to air-exposed controls. Importantly, NTHI-specific T cells from mice exposed to cigarette smoke produced lower levels of IFN-γ and IL-4, and B cells produced reduced levels of antibodies against outer membrane lipoprotein P6, with impaired IgG1, IgG2a and IgA class-switching. However, production of IL-17, which is associated with neutrophilic inflammation, was enhanced. Interestingly, cigarette smoke exposed mice exhibited a similar defect in the generation of adaptive immunity following immunization with P6. Our study has conclusively demonstrated that cigarette smoke exposure has a profound suppressive effect on the generation of adaptive immune responses to NTHI and suggests the mechanism by which prior cigarette smoke exposure predisposes COPD patients to recurrent infections, leading to exacerbations and contributing to mortality. PMID:24752444

  5. Cost of Herpes Zoster in Patients With Selected Immune-Compromised Conditions in the United States.

    PubMed

    Li, Qian; Chen, Shih-Yin; Burstin, Stuart J; Levin, Myron J; Suaya, Jose A

    2016-04-01

    Background.  This retrospective study investigates the healthcare costs of herpes zoster (HZ) in patients with selected immune-compromised (IC) conditions in the United States (US). Methods.  Patients with incident HZ diagnosis (index date) were selected from nationwide administrative claims databases from 2005 to 2009. Baseline IC groups, analyzed separately, included adults aged 18-64 years with the following: human immunodeficiency virus infection (HIV), solid organ transplant (SOT), bone marrow or stem cell transplant (BMSCT), or cancer; and older adults (aged ≥65 years) with cancer. Herpes zoster patients (n = 2020, n = 1053, n = 286, n = 13 178, and n = 9089, respectively) were 1-to-1 matched to controls without HZ (with randomly selected index date) in the same baseline group. The healthcare resource utilization and costs (2014 US dollars) during the first 2 postindex quarters were compared between matched cohorts with continuous enrollment during the quarter. Results.  Herpes zoster patients generally had greater use of inpatient, emergency room and outpatient services, and pain medications than matched controls (P < .05). The incremental costs of HZ during the first postindex quarter were $3056, $2649, $13 332, $2549, and $3108 for HIV, SOT, BMSCT, cancer in adults aged 18-64 years, and cancer in older adults, respectively (each P < .05). The incremental costs of HZ during the second quarter were only significant for adults aged 18-64 years with cancer ($1748, P < .05). The national incremental costs of HZ were projected to be $298 million annually across the 5 IC groups. Conclusions.  The healthcare cost associated with HZ among patients with studied IC conditions was sizable and occurred mainly during the first 90 days after diagnosis. PMID:27419151

  6. A Compromise Circadian Phase Position for Permanent Night Work Improves Mood, Fatigue, and Performance

    PubMed Central

    Smith, Mark R.; Fogg, Louis F.; Eastman, Charmane I.

    2009-01-01

    Study Objective: To assess night shift improvements in mood, fatigue, and performance when the misalignment between circadian rhythms and a night shift, day sleep schedule is reduced. Design: Blocks of simulated night shifts alternated with days off. Experimental subjects had interventions to delay their circadian clocks to partially align with a night shift schedule. Control subjects had no interventions. Subjects were categorized according to the degree of circadian realignment independent of whether they were in the experimental or control groups. Twelve subjects were categorized as not re-entrained, 21 as partially re-entrained, and 6 as completely re-entrained. Setting: Home sleep and laboratory night shifts. Participants: Young healthy adults. Interventions: Experimental subjects had intermittent bright light pulses during night shifts, wore dark sunglasses outside, and had scheduled sleep episodes in darkness. Measurements and Results: A computerized test battery was administered every 2 hours during day and night shifts. After about one week on the night shift schedule, which included a weekend off, the partially and completely re-entrained groups had markedly improved mood, fatigue, and performance compared to the group that was not re-entrained. The completely and partially re-entrained groups were similar to each other and had levels of mood, fatigue, and performance that were close to daytime levels. Conclusions: Partial re-entrainment to a permanent night shift schedule, which can be produced by feasible, inexpensive interventions, is associated with greatly reduced impairments during night shifts. Citation: Smith MR; Fogg LF Eastman CI. A compromise circadian phase position for permanent night work improves mood, fatigue, and performance. SLEEP 2009;32(11):1481-1489. PMID:19928387

  7. Successful Kidney Transplantation in Children With a Compromised Inferior Vena Cava

    PubMed Central

    Shishido, Seiichiro; Kawamura, Takeshi; Hamasaki, Yuko; Takahashi, Yusuke; Itabashi, Yoshihiro; Muramatsu, Masaki; Satoh, Hiroyuki; Aikawa, Atsushi

    2016-01-01

    Background Children with a compromised inferior vena cava (IVC) were previously considered unsuitable for kidney transplantation because of the technical difficulties and the increased risk of graft thrombosis secondary to inadequate renal venous outflow. Methods We conducted a retrospective study of 11 transplants in 9 patients with end-stage renal disease and thrombosed IVCs who received adult kidney allografts between 2000 and 2015. The mean age at transplantation was 7.5 ± 3.5 years. A pretransplant diagnosis of the IVC thrombosis was made in 7 patients by magnetic resonance imaging and computerized tomography, whereas there were 2 instances of intraoperative discovery of the IVC thrombosis. Results In the early cases, a kidney was placed intraperitoneally at the right iliac fossa with a venous anastomosis to the patent segment of the suprarenal IVC. After 2008, however, 6 adult-sized kidneys were subsequently placed in the left orthotopic position. Venous drainage was attained to the infrahepatic IVC (n = 3), left native renal vein (n = 2), and ascending lumbar vein (n = 1). Moreover, a venous bypass was created between the graft and the splenic vein in 2 children who showed high return pressure after the vessel was declamped. The mean glomerular filtration rate of the functioning 8 grafts 1 year posttransplant was 73.4 ± 20.4 mL/min per 1.73 m2. Of note, 6 of the grafts have been functioning well, with a mean follow-up of 66 months. Both 1- and 5-year graft survival were 81.8%. Conclusions Transplantation into the left orthotopic position and the revascularization methods are an effective set of surgical techniques that could potentially be adopted as safe and reliable transplant approaches in children with IVC thrombosis. PMID:27500272

  8. Gray matter structural compromise is equally distributed in left and right temporal lobe epilepsy.

    PubMed

    Liu, Min; Bernhardt, Boris C; Bernasconi, Andrea; Bernasconi, Neda

    2016-02-01

    In drug-resistant temporal lobe epilepsy (TLE), MRI studies have shown consistent mesiotemporal and neocortical structural alterations when comparing patients to healthy controls. It remains, however, relatively unclear whether the side of seizure focus differentially impacts the degree of structural damage. This work performed a comprehensive surface-based analysis of mesiotemporal and neocortical morphology on preoperative 1.5 T MRI in 25/35 LTLE/RTLE patients that achieved seizure freedom after surgery (i.e., Engel-I outcome; 7 ± 2 years follow-up), an imaging-independent confirmation of focus lateralization. Compared to 46 age- and sex-matched controls, both TLE groups displayed marked ipsilateral atrophy in mesiotemporal regions, while cortical thinning was bilateral. Direct contrasts between LTLE and RTLE did not reveal significant differences. Bootstrap simulations indicated low reproducibility of observing a between-cohort difference; power analysis revealed that more than 110 patients would be necessary to detect subtle differences. No difference between LTLE and RTLE was confirmed when using voxel-based morphometry, an independent proxy of gray matter volume. Similar results were obtained analyzing a separate 3 T dataset (15/15 LTLE/RTLE patients; Engel-I after 4 ± 2 years follow-up; 42 controls). Our results strongly support equivalent gray matter compromise in left and right TLE. The morphological profile of seizure-free patients, presenting with ipsilateral mesiotemporal and bilateral cortical atrophy, motivates the development of neuromarkers of outcome that consider both mesiotemporal and neocortical structures. Hum Brain Mapp 37:515-524, 2016. © 2015 Wiley Periodicals, Inc. PMID:26526187

  9. Immunosuppressive CD71+ erythroid cells compromise neonatal host defence against infection.

    PubMed

    Elahi, Shokrollah; Ertelt, James M; Kinder, Jeremy M; Jiang, Tony T; Zhang, Xuzhe; Xin, Lijun; Chaturvedi, Vandana; Strong, Beverly S; Qualls, Joseph E; Steinbrecher, Kris A; Kalfa, Theodosia A; Shaaban, Aimen F; Way, Sing Sing

    2013-12-01

    Newborn infants are highly susceptible to infection. This defect in host defence has generally been ascribed to the immaturity of neonatal immune cells; however, the degree of hyporesponsiveness is highly variable and depends on the stimulation conditions. These discordant responses illustrate the need for a more unified explanation for why immunity is compromised in neonates. Here we show that physiologically enriched CD71(+) erythroid cells in neonatal mice and human cord blood have distinctive immunosuppressive properties. The production of innate immune protective cytokines by adult cells is diminished after transfer to neonatal mice or after co-culture with neonatal splenocytes. Neonatal CD71(+) cells express the enzyme arginase-2, and arginase activity is essential for the immunosuppressive properties of these cells because molecular inhibition of this enzyme or supplementation with L-arginine overrides immunosuppression. In addition, the ablation of CD71(+) cells in neonatal mice, or the decline in number of these cells as postnatal development progresses parallels the loss of suppression, and restored resistance to the perinatal pathogens Listeria monocytogenes and Escherichia coli. However, CD71(+) cell-mediated susceptibility to infection is counterbalanced by CD71(+) cell-mediated protection against aberrant immune cell activation in the intestine, where colonization with commensal microorganisms occurs swiftly after parturition. Conversely, circumventing such colonization by using antimicrobials or gnotobiotic germ-free mice overrides these protective benefits. Thus, CD71(+) cells quench the excessive inflammation induced by abrupt colonization with commensal microorganisms after parturition. This finding challenges the idea that the susceptibility of neonates to infection reflects immune-cell-intrinsic defects and instead highlights processes that are developmentally more essential and inadvertently mitigate innate immune protection. We anticipate that

  10. Biofouling of inlet pipes affects water quality in running seawater aquaria and compromises sponge cell proliferation.

    PubMed

    Alexander, Brittany E; Mueller, Benjamin; Vermeij, Mark J A; van der Geest, Harm H G; de Goeij, Jasper M

    2015-01-01

    Marine organism are often kept, cultured, and experimented on in running seawater aquaria. However, surprisingly little attention is given to the nutrient composition of the water flowing through these systems, which is generally assumed to equal in situ conditions, but may change due to the presence of biofouling organisms. Significantly lower bacterial abundances and higher inorganic nitrogen species (nitrate, nitrite, and ammonium) were measured in aquarium water when biofouling organisms were present within a 7-year old inlet pipe feeding a tropical reef running seawater aquaria system, compared with aquarium water fed by a new, biofouling-free inlet pipe. These water quality changes are indicative of the feeding activity and waste production of the suspension- and filter-feeding communities found in the old pipe, which included sponges, bivalves, barnacles, and ascidians. To illustrate the physiological consequences of these water quality changes on a model organism kept in the aquaria system, we investigated the influence of the presence and absence of the biofouling community on the functioning of the filter-feeding sponge Halisarca caerulea, by determining its choanocyte (filter cell) proliferation rates. We found a 34% increase in choanocyte proliferation rates following the replacement of the inlet pipe (i.e., removal of the biofouling community). This indicates that the physiological functioning of the sponge was compromised due to suboptimal food conditions within the aquarium resulting from the presence of the biofouling organisms in the inlet pipe. This study has implications for the husbandry and performance of experiments with marine organisms in running seawater aquaria systems. Inlet pipes should be checked regularly, and replaced if necessary, in order to avoid excessive biofouling and to approach in situ water quality. PMID:26664799

  11. Immunosuppressive CD71+ erythroid cells compromise neonatal host defence against infection

    PubMed Central

    Elahi, Shokrollah; Ertelt, James M.; Kinder, Jeremy M.; Jiang, Tony T.; Zhang, Xuzhe; Xin, Lijun; Chaturvedi, Vandana; Strong, Beverly S.; Qualls, Joseph E.; Steinbrecher, Kris A.; Kalfa, Theodosia A.; Shaaban, Aimen F.; Way, Sing Sing

    2014-01-01

    Newborn infants are highly susceptible to infection. This defect in host defence has generally been ascribed to the immaturity of neonatal immune cells; however, the degree of hyporesponsiveness is highly variable and depends on the stimulation conditions1–7. These discordant responses illustrate the need for a more unified explanation for why immunity is compromised in neonates. Here we show that physiologically enriched CD71+ erythroid cells in neonatal mice and human cord blood have distinctive immunosuppressive properties. The production of innate immune protective cytokines by adult cells is diminished after transfer to neonatal mice or after co-culture with neonatal splenocytes. Neonatal CD71+ cells express the enzyme arginase-2, and arginase activity is essential for the immunosuppressive properties of these cells because molecular inhibition of this enzyme or supplementation with l-arginine overrides immunosuppression. In addition, the ablation of CD71+ cells in neonatal mice, or the decline in number of these cells as postnatal development progresses parallels the loss of suppression, and restored resistance to the perinatal pathogens Listeria monocytogenes and Escherichia coli8,9. However, CD71+ cell-mediated susceptibility to infection is counterbalanced by CD71+ cell-mediated protection against aberrant immune cell activation in the intestine, where colonization with commensal microorganisms occurs swiftly after parturition10,11.Conversely, circumventing such colonization by using antimicrobials or gnotobiotic germ-free mice overrides these protective benefits. Thus, CD71+ cells quench the excessive inflammation induced by abrupt colonization with commensal microorganisms after parturition. This finding challenges the idea that the susceptibility of neonates to infection reflects immune-cell-intrinsic defects and instead highlights processes that are developmentally more essential and inadvertently mitigate innate immune protection. We anticipate that

  12. Biofouling of inlet pipes affects water quality in running seawater aquaria and compromises sponge cell proliferation

    PubMed Central

    Mueller, Benjamin; Vermeij, Mark J.A.; van der Geest, Harm H.G.

    2015-01-01

    Marine organism are often kept, cultured, and experimented on in running seawater aquaria. However, surprisingly little attention is given to the nutrient composition of the water flowing through these systems, which is generally assumed to equal in situ conditions, but may change due to the presence of biofouling organisms. Significantly lower bacterial abundances and higher inorganic nitrogen species (nitrate, nitrite, and ammonium) were measured in aquarium water when biofouling organisms were present within a 7-year old inlet pipe feeding a tropical reef running seawater aquaria system, compared with aquarium water fed by a new, biofouling-free inlet pipe. These water quality changes are indicative of the feeding activity and waste production of the suspension- and filter-feeding communities found in the old pipe, which included sponges, bivalves, barnacles, and ascidians. To illustrate the physiological consequences of these water quality changes on a model organism kept in the aquaria system, we investigated the influence of the presence and absence of the biofouling community on the functioning of the filter-feeding sponge Halisarca caerulea, by determining its choanocyte (filter cell) proliferation rates. We found a 34% increase in choanocyte proliferation rates following the replacement of the inlet pipe (i.e., removal of the biofouling community). This indicates that the physiological functioning of the sponge was compromised due to suboptimal food conditions within the aquarium resulting from the presence of the biofouling organisms in the inlet pipe. This study has implications for the husbandry and performance of experiments with marine organisms in running seawater aquaria systems. Inlet pipes should be checked regularly, and replaced if necessary, in order to avoid excessive biofouling and to approach in situ water quality. PMID:26664799

  13. The up and down bobbing of human walking: a compromise between muscle work and efficiency

    PubMed Central

    Massaad, Firas; Lejeune, Thierry M; Detrembleur, Christine

    2007-01-01

    Human walking has a peculiar straight-legged style. Consequently, the body's centre of mass (CM) moves up and down with each step, which is noticeable in their up and down head bobbing while walking. This vertical CM movement enables humans to save energy via a pendulum-like mechanism but is probably a relatively recent locomotor innovation insofar as earliest bipeds may have walked flexed and flat. We investigated the mechanics, energetics, muscle efficiency and optimization of human walking by decreasing and increasing the vertical CM displacement (flat and bouncy walking) in comparison to normal walking at six speeds (1–6 km h−1). In both flat and bouncy walking, the pendular mechanism was reduced and the energy cost was increased. However, this increase was unexpectedly much sharper in flat walking where muscles provided normal mechanical work but with a decrease in muscle efficiency. In bouncy walking, muscles provided extra mechanical work in an efficient way. Our results showed that not only do humans bob up and down in normal walking to save energy via a pendulum-like mechanism but also to make their muscles work efficiently. Actually, walking flat makes the muscles work in unfavourable conditions that waste energy. Furthermore, we are still close to a flat CM displacement relative to our current ability to change this displacement, which suggests that reducing vertical CM displacement is indeed important but only to certain limits. Evolution may ultimately have chosen the best compromise between flat locomotion that requires little work to move and bouncy locomotion that improves muscle efficiency to minimize energy consumption. PMID:17463048

  14. Management of malignant airway compromise with laser and low dose rate brachytherapy. The Mayo Clinic experience

    SciTech Connect

    Schray, M.F.; McDougall, J.C.; Martinez, A.; Cortese, D.A.; Brutinel, W.M.

    1988-02-01

    Between January 1983 and October 1985, 65 patients with malignant airway compromise have had 93 flexible bronchoscopic placements of a nylon afterloading catheter for low dose rate iridium-192 temporary intraluminal brachytherapy. All patients received prior (59 patients) and/or concurrent (13 patients) external beam irradiation to tolerance and were not candidates for surgery. Forty of these patients also received neodymium-YAG laser treatment prior to brachytherapy in a planned combined approach to provide immediate symptomatic relief and facilitate catheter placement. A dose of 3000 cGy is prescribed to 5 mm and 10 mm radii over 20-40 hours in the bronchus and trachea, respectively. Of 59 patients treated with palliative intent, 40 patients (68%) have had follow-up bronchoscopy, 18 patients have had clinical follow-up only, and one patient was lost to follow-up. Of 40 patients examined by bronchoscope in follow-up, 24 (60%) responded, eight were stable, and eight progressed. Lack of progression after prior external beam radiation for periods of greater than 12 months, six-12 months and less than six months yielded response rates to brachytherapy in 83, 50 and 31%, respectively. Most patients with clinical follow-up only expired at early intervals with airway palliation from extra-airway disease progression. Four of five patients treated with curative intent are disease-free at a median of 16 months. Eleven patients have experienced fistula and/or hemorrhage, of which seven instances (11% of all patients) appear to be treatment-induced. This brachytherapy technique is simple, well tolerated, and convenient for the patient providing airway palliation in the significant majority of patients with acceptable risk.

  15. Advanced medical life support procedures in vitally compromised children by a helicopter emergency medical service

    PubMed Central

    2010-01-01

    Background To determine the advanced life support procedures provided by an Emergency Medical Service (EMS) and a Helicopter Emergency Medical Service (HEMS) for vitally compromised children. Incidence and success rate of several procedures were studied, with a distinction made between procedures restricted to the HEMS-physician and procedures for which the HEMS is more experienced than the EMS. Methods Prospective study of a consecutive group of children examined and treated by the HEMS of the eastern region of the Netherlands. Data regarding type of emergency, physiological parameters, NACA scores, treatment, and 24-hour survival were collected and subsequently analysed. Results Of the 558 children examined and treated by the HEMS on scene, 79% had a NACA score of IV-VII. 65% of the children had one or more advanced life support procedures restricted to the HEMS and 78% of the children had one or more procedures for which the HEMS is more experienced than the EMS. The HEMS intubated 38% of all children, and 23% of the children intubated and ventilated by the EMS needed emergency correction because of potentially lethal complications. The HEMS provided the greater part of intraosseous access, as the EMS paramedics almost exclusively reserved this procedure for children in cardiopulmonary resuscitation. The EMS provided pain management only to children older than four years of age, but a larger group was in need of analgesia upon arrival of the HEMS, and was subsequently treated by the HEMS. Conclusions The Helicopter Emergency Medical Service of the eastern region of the Netherlands brings essential medical expertise in the field not provided by the emergency medical service. The Emergency Medical Service does not provide a significant quantity of procedures obviously needed by the paediatric patient. PMID:20211021

  16. Cigarette smoke exposure exacerbates lung inflammation and compromises immunity to bacterial infection.

    PubMed

    Lugade, Amit A; Bogner, Paul N; Thatcher, Thomas H; Sime, Patricia J; Phipps, Richard P; Thanavala, Yasmin

    2014-06-01

    The detrimental impact of tobacco on human health is clearly recognized, and despite aggressive efforts to prevent smoking, close to one billion individuals worldwide continue to smoke. People with chronic obstructive pulmonary disease are susceptible to recurrent respiratory infections with pathogens, including nontypeable Haemophilus influenzae (NTHI), yet the reasons for this increased susceptibility are poorly understood. Because mortality rapidly increases with multiple exacerbations, development of protective immunity is critical to improving patient survival. Acute NTHI infection has been studied in the context of cigarette smoke exposure, but this is the first study, to our knowledge, to investigate chronic infection and the generation of adaptive immune responses to NTHI after chronic smoke exposure. After chronic NTHI infection, mice that had previously been exposed to cigarette smoke developed increased lung inflammation and compromised adaptive immunity relative to air-exposed controls. Importantly, NTHI-specific T cells from mice exposed to cigarette smoke produced lower levels of IFN-γ and IL-4, and B cells produced reduced levels of Abs against outer-membrane lipoprotein P6, with impaired IgG1, IgG2a, and IgA class switching. However, production of IL-17, which is associated with neutrophilic inflammation, was enhanced. Interestingly, cigarette smoke-exposed mice exhibited a similar defect in the generation of adaptive immunity after immunization with P6. Our study has conclusively demonstrated that cigarette smoke exposure has a profound suppressive effect on the generation of adaptive immune responses to NTHI and suggests the mechanism by which prior cigarette smoke exposure predisposes chronic obstructive pulmonary disease patients to recurrent infections, leading to exacerbations and contributing to mortality. PMID:24752444

  17. Immunosuppressive CD71+ erythroid cells compromise neonatal host defence against infection

    NASA Astrophysics Data System (ADS)

    Elahi, Shokrollah; Ertelt, James M.; Kinder, Jeremy M.; Jiang, Tony T.; Zhang, Xuzhe; Xin, Lijun; Chaturvedi, Vandana; Strong, Beverly S.; Qualls, Joseph E.; Steinbrecher, Kris A.; Kalfa, Theodosia A.; Shaaban, Aimen F.; Way, Sing Sing

    2013-12-01

    Newborn infants are highly susceptible to infection. This defect in host defence has generally been ascribed to the immaturity of neonatal immune cells; however, the degree of hyporesponsiveness is highly variable and depends on the stimulation conditions. These discordant responses illustrate the need for a more unified explanation for why immunity is compromised in neonates. Here we show that physiologically enriched CD71+ erythroid cells in neonatal mice and human cord blood have distinctive immunosuppressive properties. The production of innate immune protective cytokines by adult cells is diminished after transfer to neonatal mice or after co-culture with neonatal splenocytes. Neonatal CD71+ cells express the enzyme arginase-2, and arginase activity is essential for the immunosuppressive properties of these cells because molecular inhibition of this enzyme or supplementation with L-arginine overrides immunosuppression. In addition, the ablation of CD71+ cells in neonatal mice, or the decline in number of these cells as postnatal development progresses parallels the loss of suppression, and restored resistance to the perinatal pathogens Listeria monocytogenes and Escherichia coli. However, CD71+ cell-mediated susceptibility to infection is counterbalanced by CD71+ cell-mediated protection against aberrant immune cell activation in the intestine, where colonization with commensal microorganisms occurs swiftly after parturition. Conversely, circumventing such colonization by using antimicrobials or gnotobiotic germ-free mice overrides these protective benefits. Thus, CD71+ cells quench the excessive inflammation induced by abrupt colonization with commensal microorganisms after parturition. This finding challenges the idea that the susceptibility of neonates to infection reflects immune-cell-intrinsic defects and instead highlights processes that are developmentally more essential and inadvertently mitigate innate immune protection. We anticipate that these

  18. Transient Inhibition of Cell Proliferation does not Compromise Self-Renewal of Mouse Embryonic Stem Cells

    PubMed Central

    Wang, Ruoxing; Guo, Yan-Lin

    2012-01-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remains unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. PMID:22705123

  19. Diet Composition affects surgery-associated weight loss in rats with a compromised alimentary tract

    PubMed Central

    Aiyer, Harini S.; Li, Yan; Martin, Robert C.G.

    2009-01-01

    Background Esophageal adenocarcinoma (EAC) is the fastest growing cancer in terms of incidence and has a high mortality rate. The animal model to study EAC uses esophagoduodenal anastomosis (EDA) to induce mixed-reflux (bile/acid) causing esophagitis, barrett’s esophagus and EAC sequence within 6 months. However, the lack of fully functional stomach in these rats leads to the development of malnutrition. Methods We have assessed the ability of a chemically pure, purified ingredient diet (AIN-93M) to reduce surgery-associated malnutrition in rats that have undergone the EDA-surgery. Animals were either sham- (SH) or EDA-operated and fed either a grain-based rodent diet (RD) (SH-RD, n=3; EDA-RD, n=10) or a purified diet (PD) (SH-PD, n=4; EDA-PD, n=11). The animals were weighed periodically for assessment of weight gain and euthanized at the end of 24 weeks to measure esophageal tumor incidence. Results Animals that underwent sham surgery continued to gain weight throughout the study period and no tumors were detected. The EDA-operated animals had significantly lower weight gain compared with sham animals. There was no significant difference in weight gain among EDA animals fed 2 different types of diets until 9 weeks after the surgery. After 9 weeks, EDA–RD continued to lose weight significantly, whereas the weight loss leveled in EDA-PD (p<0.001). At termination, neither tissue histopathology nor tumor incidence was significantly different between the groups. Conclusion These results show that compared to a natural ingredient diet, a purified ingredient diet can reduce surgery-associated weight loss in rats with a compromised alimentary tract. This reduction in malnutrition has the potential to reduce the confounding effects of weight loss on future animal studies reported. PMID:19932903

  20. Cost of Herpes Zoster in Patients With Selected Immune-Compromised Conditions in the United States

    PubMed Central

    Li, Qian; Chen, Shih-Yin; Burstin, Stuart J.; Levin, Myron J.; Suaya, Jose A.

    2016-01-01

    Background. This retrospective study investigates the healthcare costs of herpes zoster (HZ) in patients with selected immune-compromised (IC) conditions in the United States (US). Methods. Patients with incident HZ diagnosis (index date) were selected from nationwide administrative claims databases from 2005 to 2009. Baseline IC groups, analyzed separately, included adults aged 18–64 years with the following: human immunodeficiency virus infection (HIV), solid organ transplant (SOT), bone marrow or stem cell transplant (BMSCT), or cancer; and older adults (aged ≥65 years) with cancer. Herpes zoster patients (n = 2020, n = 1053, n = 286, n = 13 178, and n = 9089, respectively) were 1-to-1 matched to controls without HZ (with randomly selected index date) in the same baseline group. The healthcare resource utilization and costs (2014 US dollars) during the first 2 postindex quarters were compared between matched cohorts with continuous enrollment during the quarter. Results. Herpes zoster patients generally had greater use of inpatient, emergency room and outpatient services, and pain medications than matched controls (P < .05). The incremental costs of HZ during the first postindex quarter were $3056, $2649, $13 332, $2549, and $3108 for HIV, SOT, BMSCT, cancer in adults aged 18–64 years, and cancer in older adults, respectively (each P < .05). The incremental costs of HZ during the second quarter were only significant for adults aged 18–64 years with cancer ($1748, P < .05). The national incremental costs of HZ were projected to be $298 million annually across the 5 IC groups. Conclusions. The healthcare cost associated with HZ among patients with studied IC conditions was sizable and occurred mainly during the first 90 days after diagnosis. PMID:27419151