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Sample records for spg13 compromises chaperonin

  1. 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.

  2. 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

  3. 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.

  4. 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

  5. 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

  6. 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.

  7. 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.

  8. 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.

  9. Archaeal-like chaperonins in bacteria

    PubMed Central

    Techtmann, Stephen M.; Robb, Frank T.

    2010-01-01

    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

  10. 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

  11. 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.

  12. 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

  13. 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.

  14. Characterization of archaeal group II chaperonin-ADP-metal fluoride complexes: implications that group II chaperonins operate as a "two-stroke engine".

    PubMed

    Iizuka, Ryo; Yoshida, Takao; Ishii, Noriyuki; Zako, Tamotsu; Takahashi, Kazunobu; Maki, Kosuke; Inobe, Tomonao; Kuwajima, Kunihiro; Yohda, Masafumi

    2005-12-01

    Group II chaperonins, found in Archaea and in the eukaryotic cytosol, act independently of a cofactor corresponding to GroES of group I chaperonins. Instead, the helical protrusion at the tip of the apical domain forms a built-in lid of the central cavity. Although many studies on the lid's conformation have been carried out, the conformation in each step of the ATPase cycle remains obscure. To clarify this issue, we examined the effects of ADP-aluminum fluoride (AlFx) and ADP-beryllium fluoride (BeFx) complexes on alpha-chaperonin from the hyperthermophilic archaeum, Thermococcus sp. strain KS-1. Biochemical assays, electron microscopic observations, and small angle x-ray scattering measurements demonstrate that alpha-chaperonin incubated with ADP and BeFx exists in an asymmetric conformation; one ring is open, and the other is closed. The result indicates that alpha-chaperonin also shares the inherent functional asymmetry of bacterial and eukaryotic cytosolic chaperonins. Most interestingly, addition of ADP and BeFx induced alpha-chaperonin to encapsulate unfolded proteins in the closed ring but did not trigger their folding. Moreover, alpha-chaperonin incubated with ATP and AlFx or BeFx adopted a symmetric closed conformation, and its functional turnover was inhibited. These forms are supposed to be intermediates during the reaction cycle of group II chaperonins.

  15. Effective ATPase activity and moderate chaperonin-cochaperonin interaction are important for the functional single-ring chaperonin system.

    PubMed

    Illingworth, Melissa; Salisbury, Jared; Li, Wenqian; Lin, Donghai; Chen, Lingling

    2015-10-01

    Escherichia coli chaperonin GroEL and its cochaperonin GroES are essential for cell growth as they assist folding of cellular proteins. The double-ring assembly of GroEL is required for the chaperone function, and a single-ring variant GroEL(SR) is inactive with GroES. Mutations in GroEL(SR) (A92T, D115N, E191G, and A399T) have been shown to render GroEL(SR)-GroES functional, but the molecular mechanism of activation is unclear. Here we examined various biochemical properties of these functional GroEL(SR)-GroES variants, including ATP hydrolysis rate, chaperonin-cochaperonin interaction, and in vitro protein folding activity. We found that, unlike the diminished ATPase activity of the inactive GroEL(SR)-GroES, all four single-ring variants hydrolyzed ATP at a level comparable to that of the double-ring GroEL-GroES. The chaperonin-cochaperonin interaction in these single-ring systems was weaker, by at least a 50-fold reduction, than the highly stable inactive GroEL(SR)-GroES. Strikingly, only GroEL(SR)D115N-GroES and GroEL(SR)A399T-GroES assisted folding of malate dehydrogenase (MDH), a commonly used folding substrate. These in vitro results are interesting considering that all four of the single-ring systems were able to substitute GroEL-GroES to support cell growth, suggesting that the precise action of chaperonin on MDH folding may not represent that on the intrinsic cellular substrates. Our findings that both effective ATP hydrolysis rate and moderate chaperonin-cochaperonin interaction are important factors for functional single-ring GroEL(SR)-GroES are reminiscent of the naturally occurring single-ring human mitochondrial chaperonin mtHsp60-mtHsp10. Differences in biochemical properties between the single- and double-ring chaperonin systems may be exploited in designing molecules for selective targeting. PMID:26271593

  16. 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.

  17. Mechanism of nucleotide sensing in group II chaperonins

    PubMed Central

    Pereira, Jose H; Ralston, Corie Y; Douglas, Nicholai R; Kumar, Ramya; Lopez, Tom; McAndrew, Ryan P; Knee, Kelly M; King, Jonathan A; Frydman, Judith; Adams, Paul D

    2012-01-01

    Group II chaperonins mediate protein folding in an ATP-dependent manner in eukaryotes and archaea. The binding of ATP and subsequent hydrolysis promotes the closure of the multi-subunit rings where protein folding occurs. The mechanism by which local changes in the nucleotide-binding site are communicated between individual subunits is unknown. The crystal structure of the archaeal chaperonin from Methanococcus maripaludis in several nucleotides bound states reveals the local conformational changes associated with ATP hydrolysis. Residue Lys-161, which is extremely conserved among group II chaperonins, forms interactions with the γ-phosphate of ATP but shows a different orientation in the presence of ADP. The loss of the ATP γ-phosphate interaction with Lys-161 in the ADP state promotes a significant rearrangement of a loop consisting of residues 160–169. We propose that Lys-161 functions as an ATP sensor and that 160–169 constitutes a nucleotide-sensing loop (NSL) that monitors the presence of the γ-phosphate. Functional analysis using NSL mutants shows a significant decrease in ATPase activity, suggesting that the NSL is involved in timing of the protein folding cycle. PMID:22193720

  18. 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

  19. 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.

  20. Essential function of the built-in lid in the allosteric regulation of eukaryotic and archaeal chaperonins

    PubMed Central

    Reissmann, Stefanie; Parnot, Charles; Booth, Christopher R; Chiu, Wah; Frydman, Judith

    2012-01-01

    Chaperonins are allosteric double-ring ATPases that mediate cellular protein folding. ATP binding and hydrolysis control opening and closing of the central chaperonin chamber, which transiently provides a protected environment for protein folding. During evolution, two strategies to close the chaperonin chamber have emerged. Archaeal and eukaryotic group II chaperonins contain a built-in lid, whereas bacterial chaperonins use a ring-shaped cofactor as a detachable lid. Here we show that the built-in lid is an allosteric regulator of group II chaperonins, which helps synchronize the subunits within one ring and, to our surprise, also influences inter-ring communication. The lid is dispensable for substrate binding and ATP hydrolysis, but is required for productive substrate folding. These regulatory functions of the lid may serve to allow the symmetrical chaperonins to function as ‘two-stroke’ motors and may also provide a timer for substrate encapsulation within the closed chamber. PMID:17460696

  1. 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

  2. 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

  3. 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

  4. Protein folding in the cytosol: chaperonin-dependent and -independent mechanisms.

    PubMed

    Netzer, W J; Hartl, F U

    1998-02-01

    Recent findings suggest that a combination of chaperonin-assisted and unassisted mechanisms operate in protein folding in the cytosol. While nascent chain-binding chaperones, such as Hsp70, could have a general role in maintaining the folding competence of translating polypeptide chains, the contribution of the cylindrical chaperonin complexes to overall folding is limited to a subset of aggregation-sensitive polypeptides. The majority of bacterial proteins are relatively small and they are synthesized rapidly and folded independently of the chaperonin GroEL in a posttranslational manner. Eukaryotes have a proportionally larger number of multi-domain proteins than bacteria. The individual domains of these proteins can be folded cotranslationally and sequentially. The use of this mechanism explains how large proteins fold independently of a chaperonin and could have been crucial in the evolution of a wide array of modular polypeptides in eukaryotes.

  5. 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

  6. Role of the chaperonin cofactor Hsp10 in protein folding and sorting in yeast mitochondria

    PubMed Central

    1994-01-01

    Protein folding in mitochondria is mediated by the chaperonin Hsp60, the homologue of E. coli GroEL. Mitochondria also contain a homologue of the cochaperonin GroES, called Hsp10, which is a functional regulator of the chaperonin. To define the in vivo role of the co- chaperonin, we have used the genetic and biochemical potential of the yeast S. cerevisiae. The HSP10 gene was cloned and sequenced and temperature-sensitive lethal hsp10 mutants were generated. Our results identify Hsp10 as an essential component of the mitochondrial protein folding apparatus, participating in various aspects of Hsp60 function. Hsp10 is required for the folding and assembly of proteins imported into the matrix compartment, and is involved in the sorting of certain proteins, such as the Rieske Fe/S protein, passing through the matrix en route to the intermembrane space. The folding of the precursor of cytosolic dihydrofolate reductase (DHFR), imported into mitochondria as a fusion protein, is apparently independent of Hsp10 function consistent with observations made for the chaperonin-mediated folding of DHFR in vitro. The temperature-sensitive mutations in Hsp10 map to a domain (residues 25-40) that corresponds to a previously identified mobile loop region of bacterial GroES and result in a reduced binding affinity of hsp10 for the chaperonin at the non-permissive temperature. PMID:7913473

  7. Diversity of Archaea in Icelandic hot springs based on 16S rRNA and chaperonin genes.

    PubMed

    Mirete, Salvador; de Figueras, Carolina G; González-Pastor, Jose E

    2011-07-01

    The diversity of archaeal communities growing in four hot springs (65-90 °C, pH 6.5) was assessed with 16S rRNA gene primers specific for the domain Archaea. Overall, mainly uncultured members of the Desulfurococcales, the Thermoproteales and the Korarchaeota, were identified. Based on this diversity, a set of chaperonin heat-shock protein (Hsp60) gene sequences from different archaeal species were aligned to design two degenerate primer sets for the amplification of the chaperonin gene: Ths and Kor (which can also detect the korarchaeotal chaperonin gene from one of the samples). A phylogenetic tree was constructed using the chaperonin sequences retrieved and other sequences from cultured representatives. The Alpha and Beta paralogs of the chaperonin gene were observed within the main clades and orthologs among them. Cultivated representatives from these clades were assigned to either paralog in the chaperonin tree. Uncultured representatives observed in the 16S rRNA gene analysis were found to be related to the Desulfurococcales. The topologies of the 16S rRNA gene and chaperonin phylogenetic trees were compared, and similar phylogenetic relationships were observed. Our results suggest that the chaperonin Hsp60 gene may be used as a phylogenetic marker for the clades found in this extreme environment.

  8. Chaperonin genes on the rise: new divergent classes and intense duplication in human and other vertebrate genomes

    PubMed Central

    2010-01-01

    Background Chaperonin proteins are well known for the critical role they play in protein folding and in disease. However, the recent identification of three diverged chaperonin paralogs associated with the human Bardet-Biedl and McKusick-Kaufman Syndromes (BBS and MKKS, respectively) indicates that the eukaryotic chaperonin-gene family is larger and more differentiated than previously thought. The availability of complete genome sequences makes possible a definitive characterization of the complete set of chaperonin sequences in human and other species. Results We identified fifty-four chaperonin-like sequences in the human genome and similar numbers in the genomes of the model organisms mouse and rat. In mammal genomes we identified, besides the well-known CCT chaperonin genes and the three genes associated with the MKKS and BBS pathological conditions, a newly-defined class of chaperonin genes named CCT8L, represented in human by the two sequences CCT8L1 and CCT8L2. Comparative analyses from several vertebrate genomes established the monophyletic origin of chaperonin-like MKKS and BBS genes from the CCT8 lineage. The CCT8L gene originated from a later duplication also in the CCT8 lineage at the onset of mammal evolution and duplicated in primate genomes. The functionality of CCT8L genes in different species was confirmed by evolutionary analyses and in human by expression data. Detailed sequence analysis and structural predictions of MKKS, BBS and CCT8L proteins strongly suggested that they conserve a typical chaperonin-like core structure but that they are unlikely to form a CCT-like oligomeric complex. The characterization of many newly-discovered chaperonin pseudogenes uncovered the intense duplication activity of eukaryotic chaperonin genes. Conclusions In vertebrates, chaperonin genes, driven by intense duplication processes, have diversified into multiple classes and functionalities that extend beyond their well-known protein-folding role as part of the

  9. 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.

  10. 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

  11. Setting the chaperonin timer: A two-stroke, two-speed, protein machine

    PubMed Central

    Grason, John P.; Gresham, Jennifer S.; Lorimer, George H.

    2008-01-01

    In a study of the timing mechanism of the chaperonin nanomachine we show that the hemicycle time (HCT) is determined by the mean residence time (MRT) of GroES on the cis ring of GroEL. In turn, this is governed by allosteric interactions within the trans ring of GroEL. Ligands that enhance the R (relaxed) state (residual ADP, the product of the previous hemicycle, and K+) extend the MRT and the HCT, whereas ligands that enhance the T (taut) state (unfolded substrate protein, SP) decrease the MRT and the HCT. In the absence of SP, the chaperonin machine idles in the resting state, but in the presence of SP it operates close to the speed limit, set by the rate of ATP hydrolysis by the cis ring. Thus, the conformational states of the trans ring largely control the speed of the complete chaperonin cycle. PMID:18988739

  12. 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

  13. Essential Role of the Chaperonin CCT in Rod Outer Segment Biogenesis

    PubMed Central

    Sinha, Satyabrata; Belcastro, Marycharmain; Datta, Poppy; Seo, Seongjin; Sokolov, Maxim

    2014-01-01

    Purpose. While some evidence suggests an essential role for the chaperonin containing t-complex protein 1 (CCT) in ciliogenesis, this function remains poorly understood mechanistically. We used transgenic mice, previously generated in our lab, and characterized by a genetically-induced suppression of CCT in rod photoreceptors as well as a malformation of the rod sensory cilia, the outer segments, to gain new insights into this underlying molecular mechanism. Methods. The CCT activity in rod photoreceptors of mice was suppressed by overexpressing the chaperonin inhibitor, phosducin-like protein short, and the ensuing changes of cellular morphology were analyzed by light and electron microscopy. Protein expression levels were studied by fluorescent microscopy and Western blotting. Results. Suppressing the chaperonin made the photoreceptors incompetent to build their outer segments. Specifically, the CCT-deficient rods appeared unable to expand the outer segment plasma membrane, and accommodate growth of this compartment. Seeking the molecular mechanisms underlying such a shortcoming, we found that the affected rods could not express normal levels of Bardet-Biedl Syndrome (BBS) proteins 2, 5, and 7 and, owing to that deficiency, were unable to assemble the BBSome, a multisubunit complex responsible for ciliary trafficking. A similar effect in response to the chaperonin suppression was also observed in cultured ciliated cells. Conclusions. Our data provide new evidence indicating the essential role of the chaperonin CCT in the biogenesis of vertebrate photoreceptor sensory cilia, and suggest that it may be due to the direct participation of the chaperonin in the posttranslational processing of selected BBS proteins and assembly of the BBSome. PMID:24854858

  14. Origin and evolution of eukaryotic chaperonins: phylogenetic evidence for ancient duplications in CCT genes.

    PubMed

    Archibald, J M; Logsdon, J M; Doolittle, W F

    2000-10-01

    Chaperonins are oligomeric protein-folding complexes which are divided into two distantly related structural classes. Group I chaperonins (called GroEL/cpn60/hsp60) are found in bacteria and eukaryotic organelles, while group II chaperonins are present in archaea and the cytoplasm of eukaryotes (called CCT/TriC). While archaea possess one to three chaperonin subunit-encoding genes, eight distinct CCT gene families (paralogs) have been characterized in eukaryotes. We are interested in determining when during eukaryotic evolution the multiple gene duplications producing the CCT subunits occurred. We describe the sequence and phylogenetic analysis of five CCT genes from TRICHOMONAS: vaginalis and seven from GIARDIA: lamblia, representatives of amitochondriate protist lineages thought to have diverged early from other eukaryotes. Our data show that the gene duplications producing the eight CCT paralogs took place prior to the organismal divergence of TRICHOMONAS: and GIARDIA: from other eukaryotes. Thus, these divergent protists likely possess completely hetero-oligomeric CCT complexes like those in yeast and mammalian cells. No close phylogenetic relationship between the archaeal chaperonins and specific CCT subunits was observed, suggesting that none of the CCT gene duplications predate the divergence of archaea and eukaryotes. The duplications producing the CCTdelta and CCTepsilon subunits, as well as CCTalpha, CCTbeta, and CCTeta, are the most recent in the CCT gene family. Our analyses show significant differences in the rates of evolution of archaeal chaperonins compared with the eukaryotic CCTs, as well as among the different CCT subunits themselves. We discuss these results in light of current views on the origin, evolution, and function of CCT complexes.

  15. Identification and electron microscopic analysis of a chaperonin oligomer from Neurospora crassa mitochondria.

    PubMed Central

    Hutchinson, E G; Tichelaar, W; Hofhaus, G; Weiss, H; Leonard, K R

    1989-01-01

    A 7-fold symmetric particle has been identified in Neurospora crassa which is most probably the mitochondrial chaperonin. The particle, about 12 nm in diameter, appears in preparations of cytochrome reductase, and is shown to contain a 60 kd protein which cross-reacts with anti-GroEL antibodies. Results of STEM mass measurement suggest that the particle is composed of 14 subunits. A preliminary interpretation of the structure of the particle based on electron microscopy is given. Its quaternary structure and molecular weight are similar to those of the recently discovered family of particles called chaperonins, found in bacteria, chloroplasts and mitochondria. Images PMID:2569968

  16. 29 CFR 18.408 - Compromise and offers to compromise.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... BEFORE THE OFFICE OF ADMINISTRATIVE LAW JUDGES Rules of Evidence Relevancy and Its Limits § 18.408 Compromise and offers to compromise. Evidence of furnishing or offering or promising to furnish, or of... for or invalidity of the claim or its amount. Evidence of conduct or statements made in...

  17. 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

  18. Residues in chaperonin GroEL required for polypeptide binding and release.

    PubMed

    Fenton, W A; Kashi, Y; Furtak, K; Horwich, A L

    1994-10-13

    Chaperonins are ring-shaped protein complexes that are essential in the cell, mediating ATP-dependent polypeptide folding in a variety of compartments. Recent studies suggest that they function through multiple rounds of binding and release of non-native proteins: with each round of ATP-driven release into the bulk solution, a substrate protein kinetically partitions between folding to the native state or rebinding to another chaperonin molecule. To gain further insight into the mechanism of polypeptide binding and release by the chaperonin GroEL from Escherichia coli, we have undertaken a mutational analysis that relates the functional properties of GroEL to its crystal structure. Our functional tests identify a putative polypeptide-binding site on the inside surface of the apical domain, facing the central channel, consisting of hydrophobic residues. These same residues are essential for binding of the co-chaperonin GroES, which is required for productive polypeptide release. A highly conserved residue, Asp 87, positioned within a putative nucleotide-binding pocket in the top of the equatorial domain, is essential for ATP hydrolysis and polypeptide release.

  19. Cystosolic chaperonin subunits have a conserved ATPase domain but diverged polypeptide-binding domains.

    PubMed

    Kim, S; Willison, K R; Horwich, A L

    1994-12-01

    CCT (also called the TCP-1 complex or TriC) is a chaperonin found in the eukaryotic cytosol, and has unique structural and functional features. Unlike homo-oligomeric chaperonins, CCT comprises at least eight different subunits, and appears to have a limited range of physiological substrates. We have analysed CCT sequences in light of the recent determination of the crystal structure and mutational identification of the functional domains of the bacterial chaperonin GroEL. A high level of identity among all chaperonin subunits is observed in those regions that correspond to the ATP-binding site of GroEL. By contrast, no significant identity is shared in the region corresponding to the polypeptide-binding region of GroEL, either between CCT subunits or between CCT subunits and GroEL. This suggests that the polypeptide-binding sites of CCT subunits have diverged both from each other and from GroEL, which may explain the apparently different range of substrates recognized by CCT.

  20. The crystal structure of yeast CCT reveals intrinsic asymmetry of eukaryotic cytosolic chaperonins

    PubMed Central

    Dekker, Carien; Roe, S Mark; McCormack, Elizabeth A; Beuron, Fabienne; Pearl, Laurence H; Willison, Keith R

    2011-01-01

    The cytosolic chaperonin CCT is a 1-MDa protein-folding machine essential for eukaryotic life. The CCT interactome shows involvement in folding and assembly of a small range of proteins linked to essential cellular processes such as cytoskeleton assembly and cell-cycle regulation. CCT has a classic chaperonin architecture, with two heterogeneous 8-membered rings stacked back-to-back, enclosing a folding cavity. However, the mechanism by which CCT assists folding is distinct from other chaperonins, with no hydrophobic wall lining a potential Anfinsen cage, and a sequential rather than concerted ATP hydrolysis mechanism. We have solved the crystal structure of yeast CCT in complex with actin at 3.8 Å resolution, revealing the subunit organisation and the location of discrete patches of co-evolving ‘signature residues' that mediate specific interactions between CCT and its substrates. The intrinsic asymmetry is revealed by the structural individuality of the CCT subunits, which display unique configurations, substrate binding properties, ATP-binding heterogeneity and subunit–subunit interactions. The location of the evolutionarily conserved N-terminus of Cct5 on the outside of the barrel, confirmed by mutational studies, is unique to eukaryotic cytosolic chaperonins. PMID:21701561

  1. 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.

  2. 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

  3. 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.

  4. Replacement of GroEL in Escherichia coli by the Group II Chaperonin from the Archaeon Methanococcus maripaludis

    PubMed Central

    Shah, Riddhi; Large, Andrew T.; Ursinus, Astrid; Lin, Bevan; Gowrinathan, Preethy; Martin, Jörg

    2016-01-01

    ABSTRACT Chaperonins are required for correct folding of many proteins. They exist in two phylogenetic groups: group I, found in bacteria and eukaryotic organelles, and group II, found in archaea and eukaryotic cytoplasm. The two groups, while homologous, differ significantly in structure and mechanism. The evolution of group II chaperonins has been proposed to have been crucial in enabling the expansion of the proteome required for eukaryotic evolution. In an archaeal species that expresses both groups of chaperonins, client selection is determined by structural and biochemical properties rather than phylogenetic origin. It is thus predicted that group II chaperonins will be poor at replacing group I chaperonins. We have tested this hypothesis and report here that the group II chaperonin from Methanococcus maripaludis (Mm-cpn) can partially functionally replace GroEL, the group I chaperonin of Escherichia coli. Furthermore, we identify and characterize two single point mutations in Mm-cpn that have an enhanced ability to replace GroEL function, including one that allows E. coli growth after deletion of the groEL gene. The biochemical properties of the wild-type and mutant Mm-cpn proteins are reported. These data show that the two groups are not as functionally diverse as has been thought and provide a novel platform for genetic dissection of group II chaperonins. IMPORTANCE The two phylogenetic groups of the essential and ubiquitous chaperonins diverged approximately 3.7 billion years ago. They have similar structures, with two rings of multiple subunits, and their major role is to assist protein folding. However, they differ with regard to the details of their structure, their cofactor requirements, and their reaction cycles. Despite this, we show here that a group II chaperonin from a methanogenic archaeon can partially substitute for the essential group I chaperonin GroEL in E. coli and that we can easily isolate mutant forms of this chaperonin with further

  5. 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

  6. 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

  7. 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

  8. 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.

  9. Single-Molecule Fluorescence Polarization Study of Conformational Change in Archaeal Group II Chaperonin

    PubMed Central

    Iizuka, Ryo; Ueno, Taro; Morone, Nobuhiro; Funatsu, Takashi

    2011-01-01

    Group II chaperonins found in archaea and in eukaryotic cytosol mediate protein folding without a GroES-like cofactor. The function of the cofactor is substituted by the helical protrusion at the tip of the apical domain, which forms a built-in lid on the central cavity. Although many studies on the change in lid conformation coupled to the binding and hydrolysis of nucleotides have been conducted, the molecular mechanism of lid closure remains poorly understood. Here, we performed a single-molecule polarization modulation to probe the rotation of the helical protrusion of a chaperonin from a hyperthermophilic archaeum, Thermococcus sp. strain KS-1. We detected approximately 35° rotation of the helical protrusion immediately after photorelease of ATP. The result suggests that the conformational change from the open lid to the closed lid state is responsible for the approximately 35° rotation of the helical protrusion. PMID:21779405

  10. A single ring is sufficient for productive chaperonin-mediated folding in vivo.

    PubMed

    Nielsen, K L; Cowan, N J

    1998-07-01

    Facilitated protein folding by the double toroidal bacterial chaperonin, GroEL/GroES, proceeds by a "two-stroke engine" mechanism in which an allosteric interaction between the two rings synchronizes the reaction cycle by controlling the binding and release of cochaperonin. Using chimeric chaperonin molecules assembled by fusing equatorial and apical domains derived from GroEL and its mammalian mitochondrial homolog, Hsp60, we show that productive folding by Hsp60 and its cognate cochaperonin, Hsp10, proceeds in vitro and in vivo without the formation of a two-ring structure. This simpler "one-stroke" engine works because Hsp60 has a different mechanism for the release of its cochaperonin cap and bound target protein.

  11. Binding, encapsulation and ejection: substrate dynamics during a chaperonin-assisted folding reaction.

    PubMed

    Ranson, N A; Burston, S G; Clarke, A R

    1997-03-01

    Mitochondrial malate dehydrogenase (mMDH) folds more rapidly in the presence of GroEL, GroES and ATP than it does unassisted. The increase in folding rate as a function of the concentration of GroEL-ES reaches a maximum at a stoichiometry which is approximately equimolar (mMDH subunits:GroEL oligomer) and with an apparent dissociation constant K' for the GroE acceptor state of at least 1 x 10(-8) M. However, even at chaperonin concentrations which are 4000 x K', i.e. at negligible concentrations of free mMDH, the observed folding rate of the substrate remains at its optimum, showing not only that folding occurs in the chaperonin-mMDH complex but also that this rate is uninhibited by any interactions with sites on GroEL. Despite the ability of mMDH to fold on the chaperonin, trapping experiments show that its dwell time on the complex is only 20 seconds. This correlates with both the rate of ATP turnover and the dwell time of GroES on the complex and is only approximately 5% of the time taken for the substrate to commit to the folded state. The results imply that ATP drives the chaperonin complex through a cycle of three functional states: (1) an acceptor complex in which the unfolded substrate is bound tightly; (2) an encapsulation state in which it is sequestered but direct protein-protein contact is lost so that folding can proceed unhindered; and (3) an ejector state which forces dissociation of the substrate whether folded or not.

  12. Refolding and reassembly of active chaperonin GroEL after denaturation.

    PubMed

    Ybarra, J; Horowitz, P M

    1995-09-22

    Conditions are reported that, for the first time, permit the folding and assembly of active chaperonin, GroEL, following denaturation in 8 m urea. The folding could be achieved by dilution or dialysis, and the best yields required the simultaneous presence of ammonium sulfate and the Mg2+ complexes of ATP or ADP. Ammonium sulfate was the key to this particular protocol, since there was a small recovery of oligomer in its presence, but no detectable recovery was induced by ATP or ADP without ammonium sulfate. The refolded/reassembled GroEL could arrest the spontaneous folding of rhodanese, and it could participate in the chaperonin-assisted refolding of rhodanese as effectively as GroEL that had never been unfolded. The results demonstrate that the primary sequence of GroEL contains the information required for its folding, assembly, and function. Thus, in contrast to previous studies, although chaperonins may facilitate GroEL folding, they are not necessary for the acquisition of the functional oligomeric state of this chaperone. This ability to fold denatured GroEL in vitro will facilitate studies of the influences that determine the interesting folding pattern adopted by the native protein. PMID:7673187

  13. 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.

  14. 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

  15. 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

  16. Chaperonin cofactors, Cpn10 and Cpn20, of green algae and plants function as hetero-oligomeric ring complexes.

    PubMed

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

    2012-06-01

    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, AtCpn60α(7)β(7). 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.

  17. Chaperonin 10 of Mycobacterium tuberculosis induces a protective immune response to foot-and-mouth disease virus.

    PubMed

    Amadori, M; Archetti, I L; Scaccaglia, P; Modena, D; Fossati, G; Lucietto, P; Mascagni, P

    1999-01-01

    Chaperonin 10 of M. tuberculosis conferred partial or total protection against generalized foot-and-mouth disease (FMD) in guinea-pigs challenged with O1 Lausanne FMD virus. Chaperonin 10-immunized animals mounted an antibody response to the protein, one epitope of which was found in the C-terminal half. A similar recognition pattern was observed in FMD-convalescent guinea-pigs, swine and cattle. Anti-chaperonin 10 sera showed antiviral activity against FMDV-infected BHK-21 cells. There was strong evidence that early after infection these cells actively secrete their histones and that antisera to the chaperonin recognize them. The same antisera reacted with purified histones in immunoblotting. Most important, exogenously added histones abrogated the anti-viral activity of the antiserum and an anti-histone monoclonal antibody had strong antiviral activity against FMDV-infected BHK-21 cells. These results are consistent with previous reports on displacement of histones from the nuclear compartment and immune recognition of self-histones after viral infections. On the whole, they indicate that M. tuberculosis chaperonin 10 enables the immune system to react against early abnormalities of virus-infected cells; this is accomplished by antibody cross-reacting with histones released during virus infection. PMID:10416374

  18. Purified chaperonin 60 (groEL) interacts with the nonnative states of a multitude of Escherichia coli proteins.

    PubMed Central

    Viitanen, P. V.; Gatenby, A. A.; Lorimer, G. H.

    1992-01-01

    In vitro experiments employing the soluble proteins from Escherichia coli reveal that about half of them, in their unfolded or partially folded states, but not in their native states, can form stable binary complexes with chaperonin 60 (groEL). These complexes can be isolated by gel filtration chromatography and are efficiently discharged upon the addition of Mg.ATP. Binary complex formation is substantially reduced if chaperonin 60 is presaturated with Rubisco-I, the folding intermediate of Rubisco, but not with native Rubisco. Binary complex formation is also reduced if the transient species that interact with chaperonin 60 are permitted to progress to more stable states. This implies that the structural elements or motifs that are recognized by chaperonin 60 and that are responsible for binary complex formation are only present or accessible in the unfolded states of proteins or in certain intermediates along their respective folding pathways. Given the high-affinity binding that we have observed in the present study and the normal cellular abundance of chaperonin 60, we suspect that the folding of most proteins in E. coli does not occur in free solution spontaneously, but instead takes place while they are associated with molecular chaperones. PMID:1363913

  19. Human CCT4 and CCT5 Chaperonin Subunits Expressed in Escherichia coli Form Biologically Active Homo-oligomers*

    PubMed Central

    Sergeeva, Oksana A.; Chen, Bo; Haase-Pettingell, Cameron; Ludtke, Steven J.; Chiu, Wah; King, Jonathan A.

    2013-01-01

    Chaperonins are a family of chaperones that encapsulate their substrates and assist their folding in an ATP-dependent manner. The ubiquitous eukaryotic chaperonin, TCP-1 ring complex (TRiC), is a hetero-oligomeric complex composed of two rings, each formed from eight different CCT (chaperonin containing TCP-1) subunits. Each CCT subunit may have distinct substrate recognition and ATP hydrolysis properties. We have expressed each human CCT subunit individually in Escherichia coli to investigate whether they form chaperonin-like double ring complexes. CCT4 and CCT5, but not the other six CCT subunits, formed high molecular weight complexes within the E. coli cells that sedimented about 20S in sucrose gradients. When CCT4 and CCT5 were purified, they were both organized as two back-to-back rings of eight subunits each, as seen by negative stain and cryo-electron microscopy. This morphology is consistent with that of the hetero-oligomeric double-ring TRiC purified from bovine testes and HeLa cells. Both CCT4 and CCT5 homo-oligomers hydrolyzed ATP at a rate similar to human TRiC and were active as assayed by luciferase refolding and human γD-crystallin aggregation suppression and refolding. Thus, both CCT4 and CCT5 homo-oligomers have the property of forming 8-fold double rings absent the other subunits, and these complexes carry out chaperonin reactions without other partner subunits. PMID:23612981

  20. The chaperonin assisted and unassisted refolding of rhodanese can be modulated by its N-terminal peptide.

    PubMed

    Mendoza, J A; Horowitz, P M

    1994-01-01

    The in vitro refolding of the monomeric, mitochondrial enzyme rhodanese (thiosulfate: cyanide sulfurtransferase, EC 2.8.1.1), which is assisted by the E. coli chaperonins, is modulated by the 23 amino acid peptide (VHQVLYRALVSTKWLAESVRAGK) corresponding to the amino terminal sequence (1-23) of rhodanese. In the absence of the peptide, a maximum recovery of active enzyme of about 65% is achieved after 90 min of initiation of the chaperonin assisted folding reaction. In contrast, this process is substantially inhibited in the presence of the peptide. The maximum recovery of active enzyme is peptide concentration-dependent. The peptide, however, does not prevent the interaction of rhodanese with the chaperonin 60 (cpn60), which leads to the formation of the cpn60-rhodanese complex. In addition, the peptide does not affect the rate of recovery of active enzyme, although it does affect the extent of recovery. Further, the unassisted refolding of rhodanese is also inhibited by the peptide. Thus, the peptide interferes with the folding of rhodanese in either the chaperonin assisted or the unassisted refolding of the enzyme. A 13 amino acid peptide (STKWLAESVRAGK) corresponding to the amino terminal sequence (11-23) of rhodanese does not show any significant effect on the chaperonin assisted or unassisted refolding of the enzyme. The results suggest that other sequences of rhodanese, in addition to the N-terminus, may be required for the binding of cpn60, in accord with a model in which cpn60 interacts with polypeptides through multiple binding sites.

  1. 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

  2. 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.

  3. 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.

  4. The eukaryote chaperonin CCT is a cold shock protein in Saccharomyces cerevisiae

    PubMed Central

    Somer, Lilach; Shmulman, Oshrit; Dror, Tali; Hashmueli, Sharon; Kashi, Yechezkel

    2002-01-01

    The eukaryotic Hsp60 cytoplasmic chaperonin CCT (chaperonin containing the T-complex polypeptide–1) is essential for growth in budding yeast, and mutations in individual CCT subunits have been shown to affect assembly of tubulin and actin. The present research focused mainly on the expression of the CCT subunits, CCTα and CCTβ, in yeast (Saccharomyces cerevisiae). Previous studies showed that, unlike most other chaperones, CCT in yeast does not undergo induction following heat shock. In this study, messenger ribonucleic acid (mRNA) and protein levels of CCT subunits following exposure to low temperatures, were examined. The Northern blot analysis indicated a 3- to 4-fold increase in mRNA levels of CCTα and CCTβ genes after cold shock at 4°C. Interestingly, Western blot analysis showed that cold shock induces an increase in the CCTα protein, which is expressed at 10°C, but not at 4°C. Transfer of 4°C cold-shocked cells to 10°C induced a 5-fold increase in the CCTα protein level. By means of fluorescent immunostaining and confocal microscopy, we found CCTα to be localized in the cortex and the cell cytoplasm of S. cerevisiae. Localization of CCTα was not affected at low temperatures. Co-localization of CCT and filaments of actin and tubulin was not observed by microscopy. The induction pattern of the CCTα protein suggests that expression of the chaperonin may be primarily important during the recovery from low temperatures and the transition to growth at higher temperatures, as found for other Hsps during the recovery phase from heat shock. PMID:11892987

  5. Heterologous production of active ribonuclease inhibitor in Escherichia coli by redox state control and chaperonin coexpression

    PubMed Central

    2011-01-01

    Background Eukaryotic Ribonuclease inhibitor (RI), belonging to the RNH1 family, is distinguished by unique features - a high sensitivity to oxidation due to the large number of reduced cysteins and a high hydrophobicity, which made most production approaches so far unsuccessful or resulted in very low yields. In this work efficient in vivo folding of native RI in the Escherichia coli cytoplasm was obtained by external addition of a reducing agent in tandem with oxygen limitation and overproduction of a molecular chaperonin. After optimisation of the production conditions in the shake flask scale the process was scaled up to high cell densities by applying a glucose limited fed-batch procedure. Results RI production in a T7 RNA polymerase based system results in accumulation of aggregated inactive product in inclusion bodies. Combination of addition of the reductant DTT, low production temperature and coexpression of the chaperonin GroELS resulted in high level production of approximately 25 mg g-1 CDW active RI in E. coli ER2566 pET21b, corresponding to approximately 800 kU g-1 cell wet weight. Further conditional screening under fed-batch-like conditions with the EnBase® technology and scale up into the bioreactor scale resulted in an efficient high cell density glucose and oxygen limited fed-batch process with a final cell dry weight of 25 g L-1 and a total RI yield of app. 625 mg L-1 (volumetric activity of 80,000 kU L-1). The E. coli based production constructs showed a very high robustness. The recombinant culture maintained its productivity despite the combination of the toxic growth conditions, the substrate limited production mode in tandem with a high level expression of several recombinant proteins, the set of molecular chaperonins and the target protein (RI). Conclusions High level production of active RI in E. coli in a T7 RNA polymerase expression system depends on the following factors: (i) addition of a reducing agent, (ii) low production

  6. 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

  7. 48 CFR 232.616 - Compromise actions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., DEPARTMENT OF DEFENSE GENERAL CONTRACTING REQUIREMENTS CONTRACT FINANCING Contract Debts 232.616 Compromise actions. Only the department/agency contract financing offices (see 232.070(c)) are authorized to compromise debts covered by this subpart....

  8. 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.

  9. 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

  10. Translocation boost protein-folding efficiency of double-barreled chaperonins.

    PubMed

    Coluzza, Ivan; van der Vies, Saskia M; Frenkel, Daan

    2006-05-15

    Incorrect folding of proteins in living cells may lead to malfunctioning of the cell machinery. To prevent such cellular disasters from happening, all cells contain molecular chaperones that assist nonnative proteins in folding into the correct native structure. One of the most studied chaperone complexes is the GroEL-GroES complex. The GroEL part has a "double-barrel" structure, which consists of two cylindrical chambers joined at the bottom in a symmetrical fashion. The hydrophobic rim of one of the GroEL chambers captures nonnative proteins. The GroES part acts as a lid that temporarily closes the filled chamber during the folding process. Several capture-folding-release cycles are required before the nonnative protein reaches its native state. Here we report molecular simulations that suggest that translocation of the nonnative protein through the equatorial plane of the complex boosts the efficiency of the chaperonin action. If the target protein is correctly folded after translocation, it is released. However, if it is still nonnative, it is likely to remain trapped in the second chamber, which then closes to start a reverse translocation process. This shuttling back and forth continues until the protein is correctly folded. Our model provides a natural explanation for the prevalence of double-barreled chaperonins. Moreover, we argue that internal folding is both more efficient and safer than a scenario where partially refolded proteins escape from the complex before being recaptured.

  11. Intermediates in the chaperonin-assisted refolding of rhodanese are trapped at low temperature and show a small stoichiometry.

    PubMed

    Mendoza, J A; Lorimer, G H; Horowitz, P M

    1991-09-15

    In vitro refolding of the urea-unfolded, monomeric, mitochondrial enzyme rhodanese (thiosulfate sulfur-transferase; EC 2.8.1.1) is facilitated by the chaperonin proteins cpn60 and cpn10 from Escherichia coli at 37 degrees C, but the refolding is strongly inhibited at 10 degrees C. In contrast, the unassisted refolding of rhodanese is efficient at 10 degrees C, but the refolding efficiency decreases as the temperature is raised. These observations provided two measures of the cpn60-rhodanese complex. Thus, we monitored either 1) the cpn60-dependent inhibition of spontaneous folding at 10 degrees C or 2) the recovery of active rhodanese in the complete chaperonin system at 25 degrees C, after first forming a cpn60-rhodanese complex at 10 degrees C. These procedures minimized the aggregation of interactive folding intermediates that tend to overestimate the apparent number of cpn60 14-mers in determining the stoichiometry of protein-cpn60 14-mer interactions. Both procedures used here gave results that were consistent with there being 1 rhodanese binding site/cpn60 tetradecamer. This stoichiometry is significantly less than might be expected from the fact that cpn60 is composed of 14 identical subunits, and it may indicate that rhodanese interacts with a restricted region that is formed when the cpn60 tetradecamer is assembled. The ability to stabilize chaperonin-protein complexes that can subsequently be reactivated will aid studies of the mode of action of the ubiquitous chaperonin proteins.

  12. 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

  13. 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

  14. 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.

  15. 6 CFR 11.11 - Compromise.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 6 Domestic Security 1 2012-01-01 2012-01-01 false Compromise. 11.11 Section 11.11 Domestic Security DEPARTMENT OF HOMELAND SECURITY, OFFICE OF THE SECRETARY CLAIMS § 11.11 Compromise. DHS may compromise a debt in accordance with the provisions of 31 CFR part 902. The Chief Financial Officer...

  16. 6 CFR 11.11 - Compromise.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 6 Domestic Security 1 2011-01-01 2011-01-01 false Compromise. 11.11 Section 11.11 Domestic Security DEPARTMENT OF HOMELAND SECURITY, OFFICE OF THE SECRETARY CLAIMS § 11.11 Compromise. DHS may compromise a debt in accordance with the provisions of 31 CFR part 902. The Chief Financial Officer...

  17. 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...

  18. 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.

  19. 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

  20. NOx and ADMA changes with focal ischemia, amelioration with the chaperonin GroEL

    PubMed Central

    Xu, Lijun; Wang, Bingyin; Kaur, Kirandeep; Kho, Melanie F.; Cooke, John P.; Giffard, Rona G.

    2008-01-01

    Both nitric oxide and asymmetrical dimethylarginine (ADMA) play a critical role in the regulation of cerebral blood flow, though their neuroprotective and cytotoxic effects are still under investigation. In this study we found that nitrate/nitrite (NOx) levels in plasma, ischemic brain tissue, and cerebrospinal fluid (CSF) increased significantly 24h after 2h transient middle cerebral artery occlusion (MCAO) in rats. ADMA levels were unchanged in plasma, but decreased significantly in CSF 24h following MCAO. The CSF ADMA/NOx ratio decreased markedly following ischemia. Rats protected by expression of the chaperonin GroEL or its folding deficient mutant D87K had lower plasma NOx levels at 24h reperfusion. ADMA, NO, and their ratio in CSF merit further study as biomarkers for ischemic brain injury. PMID:17398004

  1. Molecular cloning and characterization of a group II chaperonin delta-subunit from soybean.

    PubMed

    Nong, Van Hai; Arahira, Masaomi; Phan, Van Chi; Kim, Chan-Shick; Zhang, Deyu; Udaka, Kyoko; Fukazawa, Chikafusa

    2002-08-01

    Molecular characterization of plant group II chaperonin (CCT, c-cpn, or TriC) still remains elusive. By PCR-based cloning techniques using soybeans, we have made a successful attempt to clone a delta-subunit homologue of CCT (CCTdelta). This subunit is responsible for the binding of an in vivo substrate, alpha-actin, by assisting the correct folding of the cytoskeletal protein in mouse, and the occurrence of the subunit homologue in plant CCT was unclear. As the cloning strategy, a putative amino acid segment, NH(2)-Gly-Gly-Gly-Ala-Pro-Glu-COOH, which is tightly conserved in all known animal and yeast CCTdelta subunits, was chosen for designing a degenerate primer of the PCR-cloning. The resultant 1881-bp cDNA was found to have an open-reading frame of 533 amino acids with a calculated molecular mass of 57,677 Da and to share about 58-65% identity overall at the amino acid level with the corresponding subunits known to date. Using antibodies raised against Escherichia coli-produced soybean insoluble CCTdelta as a monitoring tool, we purified soybean CCT from the extract of its immature seeds. STEM images demonstrated that the molecular shape of soybean CCT is a double eight-membered ring, which resembles the known group II chaperonins. The CCT also reactivated a denatured firefly luciferase with a significant, but limited level of the native enzymic activity in an in vitro system. Northern blot analysis showed that soybean CCTdelta gene, which is intronless and composed of a small family, was only expressed at a very early stage of seed development of soybean.

  2. 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

  3. 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

  4. 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

  5. Substrate protein switches GroE chaperonins from asymmetric to symmetric cycling by catalyzing nucleotide exchange

    PubMed Central

    Ye, Xiang; Lorimer, George H.

    2013-01-01

    The complex kinetics of Pi and ADP release by the chaperonin GroEL/GroES is influenced by the presence of unfolded substrate protein (SP). Without SP, the kinetics of Pi release are described by four phases: a “lag,” a “burst” of ATP hydrolysis by the nascent cis ring, a “delay” caused by ADP release from the nascent trans ring, and steady-state ATP hydrolysis. The release of Pi precedes the release of ADP. The rate-determining step of the asymmetric cycle is the release of ADP from the trans ring of the GroEL-GroES1 “bullet” complex that is, consequently, the predominant species. In the asymmetric cycle, the two rings of GroEL function alternately, 180° out of phase. In the presence of SP, a change in the kinetic mechanism occurs. With SP present, the kinetics of ADP release are also described by four phases: a lag, a “surge” of ADP release attributable to SP-induced ADP/ATP exchange, and a “pause” during which symmetrical “football” particles are formed, followed by steady-state ATP hydrolysis. SP catalyzes ADP/ATP exchange on the trans ring. Now ADP release precedes the release of Pi, and the rate-determining step of the symmetric cycle becomes the hydrolysis of ATP by the symmetric GroEL-GroES2 football complex that is, consequently, the predominant species. A FRET-based analysis confirms that asymmetric GroEL-GroES1 bullets predominate in the absence of SP, whereas symmetric GroEL-GroES2 footballs predominate in the presence of SP. This evidence suggests that symmetrical football particles are the folding functional form of the chaperonin machine in vivo. PMID:24167257

  6. Exogenous delivery of chaperonin subunit fragment ApiCCT1 modulates mutant Huntingtin cellular phenotypes

    PubMed Central

    Sontag, Emily M.; Joachimiak, Lukasz A.; Tan, Zhiqun; Tomlinson, Anthony; Housman, David E.; Glabe, Charles G.; Potkin, Steven G.; Frydman, Judith; Thompson, Leslie M.

    2013-01-01

    Aggregation of misfolded proteins is characteristic of a number of neurodegenerative diseases, including Huntington disease (HD). The CCT/TRiC (chaperonin containing TCP-1/TCP-1 ring) chaperonin complex can inhibit aggregation and cellular toxicity induced by expanded repeat Huntingtin (mHtt) fragments. The substrate-binding apical domain of CCT/TRiC subunit CCT1, ApiCCT1, is sufficient to inhibit aggregation of expanded repeat mHtt fragments in vitro, providing therapeutic promise for HD. However, a key hurdle in considering ApiCCT1 as a potential treatment is in delivery. Because ApiCCT1 has a region of similarity to the HIV Tat protein cell-transduction domain, we tested whether recombinant ApiCCT1 (ApiCCT1r) protein could enter cells following exogenous delivery and modulate an established panel of mHtt-mediated cell-based phenotypes. Cell fractionation studies demonstrate that exogenous ApiCCT1r can penetrate cell membranes and can localize to the nucleus, consistent with a strategy that can target both cytosolic and nuclear pathogenic events in HD. ApiCCT1r application does indeed modulate HD cellular phenotypes by decreasing formation of visible inclusions, fibrillar oligomers, and insoluble mHtt derived from expression of a truncated mHtt exon 1 fragment. ApiCCT1r also delays the onset of inclusion body formation as visualized via live imaging. ApiCCT1r reduces mHtt-mediated toxicity in immortalized striatal cells derived from full-length knock-in HD mice, suggesting that therapeutic benefit may extend beyond effects on aggregation. These studies provide the basis for a potentially robust and unique therapeutic strategy to target mHtt-mediated protein pathogenesis. PMID:23365139

  7. A Single-Ring Mitochondrial Chaperonin (Hsp60-Hsp10) Can Substitute for GroEL-GroES In Vivo

    PubMed Central

    Nielsen, Kåre L.; McLennan, Neil; Masters, Millicent; Cowan, Nicholas J.

    1999-01-01

    Chaperonins participate in the facilitated folding of a variety of proteins in vivo. To see whether the same spectrum of target proteins can be productively folded by the double-ring prokaryotic chaperonin GroEL-GroES and its single-ring human mitochondrial homolog, Hsp60-Hsp10, we expressed the latter in an Escherichia coli strain engineered so that the groE operon is under strict regulatory control. We found that expression of Hsp60-Hsp10 restores viability to cells that no longer express GroEL-GroES, formally demonstrating that Hsp60-Hsp10 can carry out all essential in vivo functions of GroEL-GroES. PMID:10482535

  8. 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.

  9. 48 CFR 32.610 - Compromising debts.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Standards (31 CFR part 902) and agency regulations. Unless specifically authorized by agency procedures... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Compromising debts. 32.610... REQUIREMENTS CONTRACT FINANCING Contract Debts 32.610 Compromising debts. For debts under $100,000,...

  10. 48 CFR 1432.610 - Compromising debts.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 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...

  11. 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...

  12. 48 CFR 32.610 - Compromising debts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Standards (31 CFR part 902) and agency regulations. Unless specifically authorized by agency procedures... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Compromising debts. 32.610... REQUIREMENTS CONTRACT FINANCING Contract Debts 32.610 Compromising debts. For debts under $100,000,...

  13. 49 CFR 1503.425 - Compromise orders.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Assessment of Civil Penalties by TSA § 1503.425 Compromise orders. (a) Issuance. At any time before the... Violation, may agree to dispose of the case by the issuance of a compromise order by TSA. (b) Contents. A... that the person agrees to pay the civil penalty specified. (4) A statement that TSA makes no finding...

  14. On the role of groES in the chaperonin-assisted folding reaction. Three case studies.

    PubMed

    Schmidt, M; Buchner, J; Todd, M J; Lorimer, G H; Viitanen, P V

    1994-04-01

    The mechanism by which correctly folded proteins are recovered from stable complexes with groEL is not well understood. Certain target proteins require ATP and groES, while others seemingly dispense with the cochaperonin. Here, we examine the chaperonin-assisted folding of ribulose-1,5-bisphosphate carboxylase, malate dehydrogenase, and citrate synthase, three proteins that are believed to require both chaperonin components for successful reactivation. Surprisingly, in all cases, the need for groES depended on the folding environment. Under "non-permissive" conditions, where unassisted spontaneous folding could not occur, reactivation to the native state required the complete chaperonin system (e.g. groEL, groES, and MgATP). However, under "permissive" conditions where spontaneous folding could occur groES was no longer mandatory. Instead, upon the addition of ATP alone, all three target proteins could be released from groEL, in a form that was capable of reaching the native state. In the permissive setting, groES merely accelerated the rate of the ATP-dependent release process. The results suggest that the incompletely folded protein species that are released from groEL, in the absence of groES, are not necessarily committed to the native state. Similar to the unassisted folding reaction, they still partition between productive and unproductive folding pathways in an environment-dependent manner. It follows that the mechanistic contribution of the co-chaperonin, groES, and its physiological significance in cellular protein folding, could be entirely missed in a permissive in vitro environment.

  15. GroEL/ES chaperonin modulates the mechanism and accelerates the rate of TIM-barrel domain folding.

    PubMed

    Georgescauld, Florian; Popova, Kristina; Gupta, Amit J; Bracher, Andreas; Engen, John R; Hayer-Hartl, Manajit; Hartl, F Ulrich

    2014-05-01

    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 timescale, avoiding aggregation or degradation.

  16. MgATP binding to the nucleotide-binding domains of the eukaryotic cytoplasmic chaperonin induces conformational changes in the putative substrate-binding domains.

    PubMed Central

    Szpikowska, B. K.; Swiderek, K. M.; Sherman, M. A.; Mas, M. T.

    1998-01-01

    The eukaryotic cytosolic chaperonins are large heterooligomeric complexes with a cylindrical shape, resembling that of the homooligomeric bacterial counterpart, GroEL. In analogy to GroEL, changes in shape of the cytosolic chaperonin have been detected in the presence of MgATP using electron microscopy but, in contrast to the nucleotide-induced conformational changes in GroEL, no details are available about the specific nature of these changes. The present study identifies the structural regions of the cytosolic chaperonin that undergo conformational changes when MgATP binds to the nucleotide binding domains. It is shown that limited proteolysis with trypsin in the absence of MgATP cleaves each of the eight subunits approximately in half, generating two fragments of approximately 30 kDa. Using mass spectrometry (MS) and N-terminal sequence analysis, the cleavage is found to occur in a narrow span of the amino acid sequence, corresponding to the peptide binding regions of GroEL and to the helical protrusion, recently identified in the structure of the substrate binding domain of the archeal group II chaperonin. This proteolytic cleavage is prevented by MgATP but not by ATP in the absence of magnesium, ATP analogs (MgATPyS and MgAMP-PNP) or MgADP. These results suggest that, in analogy to GroEL, binding of MgATP to the nucleotide binding domains of the cytosolic chaperonin induces long range conformational changes in the polypeptide binding domains. It is postulated that despite their different subunit composition and substrate specificity, group I and group II chaperonins may share similar, functionally-important, conformational changes. Additional conformational changes are likely to involve a flexible helix-loop-helix motif, which is characteristic for all group II chaperonins. PMID:9684884

  17. 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

  18. 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

  19. A zinc-binding site by negative selection induces metallodrug susceptibility in an essential chaperonin.

    PubMed

    Cun, Shujian; Sun, Hongzhe

    2010-03-16

    GroES is an indispensable chaperonin virtually found throughout all life forms. Consequently, mutations of this protein must be critically scrutinized by natural selection. Nevertheless, the homolog from a potentially virulent gastric pathogen, Helicobacter pylori, strikingly features a histidine/cysteine-rich C terminus that shares no significant homology with other family members. Additionally, three more (H45, C51, and C53) are uniquely present in its apical domain. The statistical analyses show that these residues may have originated from negative selection, presumably driven by either dependent or independent amino acid mutations. In the absence of the C-terminal metal-binding domain, the mutant protein still exhibits a substantial capacity for zinc binding in vivo. The biochemical properties of site-directed mutants indicate that H45, C51, and C53 make up an oxidation-sensitive zinc-binding site that may donate the bound metal to a zinc acceptor. Of interest, bismuth antiulcer drugs strongly bind at this site (K(d) of approximately 7 x 10(-26) M), replacing the bound zinc and consequently inducing the disruption of the quaternary structure. Because biological features by negative selection are usually inert to change during evolution, this study sheds light on a promising field whereby medicines can be designed or improved to specifically target the residues that uniquely evolved in pathogenic proteins so as to retard the emergence of drug resistance. PMID:20194796

  20. Chaperonin-Inspired pH Protection by Mesoporous Silica SBA-15 on Myoglobin and Lysozyme.

    PubMed

    Lynch, Michele M; Liu, Jichuan; Nigra, Michael; Coppens, Marc-Olivier

    2016-09-20

    While enzymes are valuable tools in many fields of biotechnology, they are fragile and must be protected against denaturing conditions such as unfavorable solution pH. Within living organisms, chaperonins help enzymes fold into their native shape and protect them from damage. Inspired by this natural solution, mesoporous silica SBA-15 with different pore diameters is synthesized as a support material for immobilizing and protecting enzymes. In separate experiments, the model enzymes myoglobin and lysozyme are physically adsorbed to SBA-15 and exposed to a range of buffered pH conditions. The immobilized enzymes' biocatalytic activities are quantified and compared to the activities of nonimmobilized enzymes in the same solution conditions. It has been observed that myoglobin immobilized on SBA-15 is protected from acidic denaturation from pH 3.6 to 5.1, exhibiting relative activity of up to 350%. Immobilized lysozyme is protected from unfavorable conditions from pH 6.6 to 7.6, with relative activity of up to 200%. These results indicate that the protective effects conferred to enzymes immobilized by physical adsorption to SBA-15 are driven by the enzymes' electrostatic attraction to the material's surface. The pore diameter of SBA-15 affects the quality of protection given to immobilized enzymes, but the contribution of this effect at different pH values remains unclear.

  1. CCTα and CCTδ Chaperonin Subunits Are Essential and Required for Cilia Assembly and Maintenance in Tetrahymena

    PubMed Central

    Seixas, Cecilia; Cruto, Teresa; Tavares, Alexandra; Gaertig, Jacek; Soares, Helena

    2010-01-01

    Background The eukaryotic cytosolic chaperonin CCT is a hetero-oligomeric complex formed by two rings connected back-to-back, each composed of eight distinct subunits (CCTα to CCTζ). CCT complex mediates the folding, of a wide range of newly synthesised proteins including tubulin (α, β and γ) and actin, as quantitatively major substrates. Methodology/Principal Findings We disrupted the genes encoding CCTα and CCTδ subunits in the ciliate Tetrahymena. Cells lacking the zygotic expression of either CCTα or CCTδ showed a loss of cell body microtubules, failed to assemble new cilia and died within 2 cell cycles. We also show that loss of CCT subunit activity leads to axoneme shortening and splaying of tips of axonemal microtubules. An epitope-tagged CCTα rescued the gene knockout phenotype and localized primarily to the tips of cilia. A mutation in CCTα, G346E, at a residue also present in the related protein implicated in the Bardet Biedel Syndrome, BBS6, also caused defects in cilia and impaired CCTα localization in cilia. Conclusions/Significance Our results demonstrate that the CCT subunits are essential and required for ciliary assembly and maintenance of axoneme structure, especially at the tips of cilia. PMID:20502701

  2. 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

  3. Conversion of a Chaperonin GroEL-independent Protein into an Obligate Substrate*

    PubMed Central

    Ishimoto, Takuya; Fujiwara, Kei; Niwa, Tatsuya; Taguchi, Hideki

    2014-01-01

    Chaperones assist protein folding by preventing unproductive protein aggregation in the cell. In Escherichia coli, chaperonin GroEL/GroES (GroE) is the only indispensable chaperone and is absolutely required for the de novo folding of at least ∼60 proteins. We previously found that several orthologs of the obligate GroE substrates in Ureaplasma urealyticum, which lacks the groE gene in the genome, are E. coli GroE-independent folders, despite their significant sequence identities. Here, we investigated the key features that define the GroE dependence. Chimera or random mutagenesis analyses revealed that independent multiple point mutations, and even single mutations, were sufficient to confer GroE dependence on the Ureaplasma MetK. Strikingly, the GroE dependence was well correlated with the propensity to form protein aggregates during folding. The results reveal the delicate balance between GroE dependence and independence. The function of GroE to buffering the aggregation-prone mutations plays a role in maintaining higher genetic diversity of proteins. PMID:25288795

  4. The chaperonin genes of jakobid and jakobid-like flagellates: implications for eukaryotic evolution.

    PubMed

    Archibald, John M; O'Kelly, Charles J; Doolittle, W Ford

    2002-04-01

    The jakobids are free-living mitochondriate protists that share ultrastructural features with certain amitochondriate groups and possess the most bacterial-like mitochondrial genomes described thus far. Jakobids belong to a diverse group of mitochondriate and amitochondriate eukaryotes, the excavate taxa. The relationships among the various excavate taxa and their relationships to other putative deep-branching protist groups are largely unknown. With the hope of clarifying these issues, we have isolated the cytosolic chaperonin CCTalpha gene from the jakobid Reclinomonas americana (strains 50394 and 50283), the jakobid-like malawimonad Malawimonas jakobiformis, two heteroloboseans (Acrasis rosea and Naegleria gruberi), a euglenozoan (Trypanosoma brucei), and a parabasalid (Monocercomonas sp.). We also amplified the CCTdelta gene from M. jakobiformis. The Reclinomonas and Malawimonas sequences presented here are among the first nuclear protein-coding genes to be described from these organisms. Unlike other putative early diverging protist lineages, a high density of spliceosomal introns was found in the jakobid and malawimonad CCTs-similar to that observed in vertebrate protein-coding genes. An analysis of intron positions in CCT genes from protists, plants, animals, and fungi suggests that many of the intron-sparse or intron-lacking protist lineages may not be primitively so but have lost spliceosomal introns during their evolutionary history. In phylogenetic trees constructed from CCTalpha protein sequences, R. americana (but not M. jakobiformis) shows a weak but consistent affinity for the Heterolobosea and Euglenozoa.

  5. First characterization of co-chaperonin protein 10 from hyper-thermophilic Aquifex aeolicus.

    PubMed

    Guidry, Jesse; Wittung-Stafshede, Pernilla

    2004-04-23

    All known co-chaperonin protein 10 (cpn10) molecules are heptamers of seven identical subunits that are linked together by beta-strand interactions. Here, we report the first characterization of a cpn10 protein from a thermophilic organism: Aquifex aeolicus. Primary-structure alignment of A. aeolicus cpn10 (Aaecpn10) shows high homology with mesophilic cpn10 sequences, except for a unique 25-residue C-terminal extension not found in any other cpn10. Recombinant Aaecpn10 adopts a heptameric structure in solution at pH values above 4 (20 degrees C). Both monomers and heptamers are folded at 20 degrees C, although the thermal stability of the monomers (pH 3; Tm approximately 58 degrees C) is lower than that of the heptamers (pH 7; Tm approximately 115 degrees C). Aaecpn10 functions in a GroEL-dependent in vitro activity assay. Taken together, Aaecpn10 appears similar in secondary, tertiary, and quaternary structure, as well as in many biophysical features, to its mesophilic counterparts despite a functional temperature of 90 degrees C.

  6. Engineering cellular robustness of microbes by introducing the GroESL chaperonins from extremophilic bacteria.

    PubMed

    Luan, Guodong; Dong, Hongjun; Zhang, Tianrui; Lin, Zhao; Zhang, Yanping; Li, Yin; Cai, Zhen

    2014-05-20

    The cellular robustness is a big concern for efficient microbial production of biofuels and biochemicals. In this study, the groESL genes from extremophilic bacteria were found to serve as transplantable stress-response elements to improve diverse types of stress-tolerances of other microbes. By overexpressing the groESL from the solvent-tolerant Pseudomonas putida in Escherichia coli, its thermo-tolerance and ethanol-tolerance were significantly increased. Meanwhile, the groESL from the thermophilic Thermoanaerobacter tengcongensis endowed Clostridium acetobutylicum with improved corn cob hydrolysates (CCH)-tolerance as well as elevated butanol productivity. The chaperonins GroESL have been widely considered as cellular stress-response proteins and overexpression of native groESL has been proven to improve cellular tolerances facing various stresses. Here we found that the groESL genes from extremophilic bacteria were superior to the native ones, possibly because they have adapted to the environmental stresses during long-term natural evolution. Moreover, our results also revealed that different extreme groESL genes performed quite different in different microbes. Thus the relation and compatibility between the extremophiles and the host must be considered for selection of the proper groESL for engineering microbial robustness. PMID:24637367

  7. 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.

  8. 19 CFR 172.33 - Acceptance of offers in compromise.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Compromise § 172.33 Acceptance of offers in compromise. An offer in compromise will be considered accepted only when the offeror is so notified in writing. As a condition to accepting an offer in compromise... 19 Customs Duties 2 2010-04-01 2010-04-01 false Acceptance of offers in compromise. 172.33...

  9. 45 CFR 30.22 - Bases for compromise.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 45 Public Welfare 1 2013-10-01 2013-10-01 false Bases for compromise. 30.22 Section 30.22 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CLAIMS COLLECTION Debt Compromise § 30.22 Bases for compromise. (a) Compromise. The Secretary may compromise a debt if the full...

  10. 45 CFR 30.22 - Bases for compromise.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 1 2014-10-01 2014-10-01 false Bases for compromise. 30.22 Section 30.22 Public Welfare Department of Health and Human Services GENERAL ADMINISTRATION CLAIMS COLLECTION Debt Compromise § 30.22 Bases for compromise. (a) Compromise. The Secretary may compromise a debt if the full...

  11. 45 CFR 30.22 - Bases for compromise.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 1 2012-10-01 2012-10-01 false Bases for compromise. 30.22 Section 30.22 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CLAIMS COLLECTION Debt Compromise § 30.22 Bases for compromise. (a) Compromise. The Secretary may compromise a debt if the full...

  12. 45 CFR 30.22 - Bases for compromise.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Bases for compromise. 30.22 Section 30.22 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CLAIMS COLLECTION Debt Compromise § 30.22 Bases for compromise. (a) Compromise. The Secretary may compromise a debt if the full...

  13. 45 CFR 30.22 - Bases for compromise.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 1 2011-10-01 2011-10-01 false Bases for compromise. 30.22 Section 30.22 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CLAIMS COLLECTION Debt Compromise § 30.22 Bases for compromise. (a) Compromise. The Secretary may compromise a debt if the full...

  14. 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...

  15. 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

  16. 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

  17. 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.

  18. Association of the influenza virus RNA polymerase subunit PB2 with the host chaperonin CCT.

    PubMed

    Fislová, Tatiana; Thomas, Benjamin; Graef, Katy M; Fodor, Ervin

    2010-09-01

    The RNA polymerase of influenza A virus is a host range determinant and virulence factor. In particular, the PB2 subunit of the RNA polymerase has been implicated as a crucial factor that affects cell tropism as well as virulence in animal models. These findings suggest that host factors associating with the PB2 protein may play an important role during viral replication. In order to identify host factors that associate with the PB2 protein, we purified recombinant PB2 from transiently transfected mammalian cells and identified copurifying host proteins by mass spectrometry. We found that the PB2 protein associates with the cytosolic chaperonin containing TCP-1 (CCT), stress-induced phosphoprotein 1 (STIP1), FK506 binding protein 5 (FKBP5), alpha- and beta-tubulin, Hsp60, and mitochondrial protein p32. Some of these binding partners associate with each other, suggesting that PB2 might interact with these proteins in multimeric complexes. More detailed analysis of the interaction of the PB2 protein with CCT revealed that PB2 associates with CCT as a monomer and that the CCT binding site is located in a central region of the PB2 protein. PB2 proteins from various influenza virus subtypes and origins can associate with CCT. Silencing of CCT resulted in reduced viral replication and reduced PB2 protein and viral RNA accumulation in a ribonucleoprotein reconstitution assay, suggesting an important function for CCT during the influenza virus life cycle. We propose that CCT might be acting as a chaperone for PB2 to aid its folding and possibly its incorporation into the trimeric RNA polymerase complex.

  19. 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

  20. 26 CFR 301.7122-1 - Compromises.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... of offers in cases where the Internal Revenue Service (IRS) is unable to locate the taxpayer's return... this section, the IRS may compromise to promote effective tax administration where compelling public... would permit the IRS to effect collection of the taxpayer's liability from such property (e.g.,...

  1. 26 CFR 301.7122-1 - Compromises.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... of offers in cases where the Internal Revenue Service (IRS) is unable to locate the taxpayer's return... this section, the IRS may compromise to promote effective tax administration where compelling public... would permit the IRS to effect collection of the taxpayer's liability from such property (e.g.,...

  2. 26 CFR 301.7122-1 - Compromises.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... of offers in cases where the Internal Revenue Service (IRS) is unable to locate the taxpayer's return... this section, the IRS may compromise to promote effective tax administration where compelling public... would permit the IRS to effect collection of the taxpayer's liability from such property (e.g.,...

  3. Uneasy Compromise: Language and Education in Moldova

    ERIC Educational Resources Information Center

    Ciscel, Matthew

    2008-01-01

    This study reports on the uneasy compromise in language and education policies in the post-Soviet Republic of Moldova since its first moves toward independence in 1989. Taking an approach that posits language policies as needing to be anchored in both international norms and the idiosyncrasies of local conditions, the discussion explores the…

  4. 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…

  5. Asp-52 in combination with Asp-398 plays a critical role in ATP hydrolysis of chaperonin GroEL.

    PubMed

    Koike-Takeshita, Ayumi; Mitsuoka, Kaoru; Taguchi, Hideki

    2014-10-24

    The Escherichia coli chaperonin GroEL is a double-ring chaperone that assists protein folding with the aid of GroES and ATP. Asp-398 in GroEL is known as one of the critical residues on ATP hydrolysis because GroEL(D398A) mutant is deficient in ATP hydrolysis (<2% of the wild type) but not in ATP binding. In the archaeal Group II chaperonin, another aspartate residue, Asp-52 in the corresponding E. coli GroEL, in addition to Asp-398 is also important for ATP hydrolysis. We investigated the role of Asp-52 in GroEL and found that ATPase activity of GroEL(D52A) and GroEL(D52A/D398A) mutants was ∼ 20% and <0.01% of wild-type GroEL, respectively, indicating that Asp-52 in E. coli GroEL is also involved in the ATP hydrolysis. GroEL(D52A/D398A) formed a symmetric football-shaped GroEL-GroES complex in the presence of ATP, again confirming the importance of the symmetric complex during the GroEL ATPase cycle. Notably, the symmetric complex of GroEL(D52A/D398A) was extremely stable, with a half-time of ∼ 150 h (∼ 6 days), providing a good model to characterize the football-shaped complex.

  6. 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

  7. 19 CFR 171.32 - Acceptance of offers in compromise.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Acceptance of offers in compromise. An offer in compromise will be considered accepted only when the offeror is so notified in writing. As a condition to accepting an offer in compromise, the offeror may be... 19 Customs Duties 2 2010-04-01 2010-04-01 false Acceptance of offers in compromise. 171.32...

  8. 10 CFR 1015.302 - Bases for compromise.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Bases for compromise. 1015.302 Section 1015.302 Energy DEPARTMENT OF ENERGY (GENERAL PROVISIONS) COLLECTION OF CLAIMS OWED THE UNITED STATES Standards for the Compromise of Claims § 1015.302 Bases for compromise. (a) DOE may compromise a debt if the Government...

  9. 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...

  10. 38 CFR 1.931 - Bases for compromise.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 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...

  11. 10 CFR 1015.302 - Bases for compromise.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Bases for compromise. 1015.302 Section 1015.302 Energy DEPARTMENT OF ENERGY (GENERAL PROVISIONS) COLLECTION OF CLAIMS OWED THE UNITED STATES Standards for the Compromise of Claims § 1015.302 Bases for compromise. (a) DOE may compromise a debt if the Government...

  12. 10 CFR 1015.302 - Bases for compromise.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Bases for compromise. 1015.302 Section 1015.302 Energy DEPARTMENT OF ENERGY (GENERAL PROVISIONS) COLLECTION OF CLAIMS OWED THE UNITED STATES Standards for the Compromise of Claims § 1015.302 Bases for compromise. (a) DOE may compromise a debt if the Government...

  13. 10 CFR 1015.302 - Bases for compromise.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Bases for compromise. 1015.302 Section 1015.302 Energy DEPARTMENT OF ENERGY (GENERAL PROVISIONS) COLLECTION OF CLAIMS OWED THE UNITED STATES Standards for the Compromise of Claims § 1015.302 Bases for compromise. (a) DOE may compromise a debt if the Government...

  14. 38 CFR 1.931 - Bases for compromise.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 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...

  15. 38 CFR 1.931 - Bases for compromise.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 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...

  16. 10 CFR 1015.302 - Bases for compromise.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Bases for compromise. 1015.302 Section 1015.302 Energy DEPARTMENT OF ENERGY (GENERAL PROVISIONS) COLLECTION OF CLAIMS OWED THE UNITED STATES Standards for the Compromise of Claims § 1015.302 Bases for compromise. (a) DOE may compromise a debt if the Government...

  17. 38 CFR 1.931 - Bases 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 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...

  18. 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

  19. 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

  20. Mitochondrial hsp60 chaperonopathy causes an autosomal-recessive neurodegenerative disorder linked to brain hypomyelination and leukodystrophy.

    PubMed

    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

    2008-07-01

    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.

  1. Compromises in career-related decisions: examining the role of compromise severity.

    PubMed

    Wee, Serena

    2014-10-01

    This study tested L. S. Gottfredson's (1996) revised compromise theory by examining whether the relative importance of job sex type, job prestige, and person-job interest congruence for predicting job choice changed as the level of compromise required changed. The fully within-persons design had participants engage in a simulated occupational choice task where job sex type and job prestige were manipulated to be experimentally independent. Participants 1st categorized jobs as unacceptable, acceptable, or preferred. Then, within each category, they made further pairwise choices among jobs in that category. In Study 1, participants were 168 college seniors (124 women, 44 men) from a large Midwestern university. In Study 2, participants were 262 (146 women, 116 men) individuals residing in the United States and recruited via Amazon's Mechanical Turk platform. Across both studies, job sex type predicted choice when large compromises were required. Across both studies, job prestige did not predict choice when moderate compromises were required. In Study 2 but not Study 1, person-job interest congruence predicted choice when minimal compromises were required. PMID:25111706

  2. 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

  3. 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.

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

    PubMed

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

    2015-11-20

    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.

  5. 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

  6. Chaperonin-containing TCP-1 complex directly binds to the cytoplasmic domain of the LOX-1 receptor

    PubMed Central

    Bakthavatsalam, Deenadayalan; Soung, Roh Hun; Tweardy, David J.; Chiu, Wah; Dixon, Richard A.F.; Woodside, Darren G.

    2014-01-01

    Lectin-like oxidized low-density lipoprotein receptor (LOX-1) is a scavenger receptor that binds oxidized low-density lipoprotein (OxLDL) and has a role in atherosclerosis development. The N-terminus intracellular region (cytoplasmic domain) of LOX-1 mediates receptor internalization and trafficking, potentially through intracellular protein interactions. Using affinity isolation, we identified 6 of the 8 components of the chaperonin-containing TCP-1 (CCT) complex bound to LOX-1 cytoplasmic domain, which we verified by coimmunoprecipitation and immunostaining in human umbilical vein endothelial cells. We found that the interaction between CCT and LOX-1 is direct and ATP-dependent and that OxLDL suppressed this interaction. Understanding the association between LOX-1 and the CCT complex may facilitate the design of novel therapies for cardiovascular disease. PMID:24846140

  7. 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

  8. 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...

  9. 31 CFR 902.2 - Bases for compromise.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Bases for compromise. 902.2 Section 902.2 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FEDERAL CLAIMS... CLAIMS § 902.2 Bases for compromise. (a) Agencies may compromise a debt if the Government cannot...

  10. 31 CFR 902.2 - Bases for compromise.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Bases for compromise. 902.2 Section 902.2 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FEDERAL CLAIMS... CLAIMS § 902.2 Bases for compromise. (a) Agencies may compromise a debt if the Government cannot...

  11. 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... CLAIMS § 902.2 Bases for compromise. (a) Agencies may compromise a debt if the Government cannot...

  12. 31 CFR 902.2 - Bases for compromise.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Bases for compromise. 902.2 Section 902.2 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FEDERAL CLAIMS... CLAIMS § 902.2 Bases for compromise. (a) Agencies may compromise a debt if the Government cannot...

  13. 31 CFR 902.2 - Bases for compromise.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Bases for compromise. 902.2 Section 902.2 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FEDERAL CLAIMS... CLAIMS § 902.2 Bases for compromise. (a) Agencies may compromise a debt if the Government cannot...

  14. 6 CFR 13.46 - Compromise or settlement.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 6 Domestic Security 1 2012-01-01 2012-01-01 false Compromise or settlement. 13.46 Section 13.46 Domestic Security DEPARTMENT OF HOMELAND SECURITY, OFFICE OF THE SECRETARY PROGRAM FRAUD CIVIL REMEDIES § 13.46 Compromise or settlement. (a) Parties may Make offers of compromise or settlement at any...

  15. 6 CFR 13.46 - Compromise or settlement.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 6 Domestic Security 1 2011-01-01 2011-01-01 false Compromise or settlement. 13.46 Section 13.46 Domestic Security DEPARTMENT OF HOMELAND SECURITY, OFFICE OF THE SECRETARY PROGRAM FRAUD CIVIL REMEDIES § 13.46 Compromise or settlement. (a) Parties may Make offers of compromise or settlement at any...

  16. 45 CFR 30.25 - Further review of compromise offers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Further review of compromise offers. 30.25 Section 30.25 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CLAIMS COLLECTION Debt Compromise § 30.25 Further review of compromise offers. If the Secretary is uncertain whether...

  17. Characterization of Protein and Transcript Levels of the Chaperonin Containing Tailless Complex Protein-1 and Tubulin during Light-Regulated Growth of Oat Seedlings1

    PubMed Central

    Moser, Michael; Schäfer, Eberhard; Ehmann, Bruno

    2000-01-01

    In grass seedlings the network of cortical microtubules is reorganized during light-dependent growth of coleoptiles and mesocotyls. We investigated the effects of light-dependent growth on the relative steady-state levels of the mRNAs and protein levels of α-tubulin and the ε-subunit of the chaperonin containing tailless complex protein-1 in oat (Avena sativa) coleoptiles, which were grown in different light conditions to establish different growth responses. The soluble pools of the ε-subunit of the chaperonin containing tailless complex protein-1 and α-tubulin decreased in nonelongating coleoptiles, suggesting that the dynamics of the light-regulated soluble pool reflect the processes occurring during reorganization of cortical microtubules. The shifts in pool sizes are discussed in relation to the machinery that controls the dynamic structure of cortical microtubules in plant cells. PMID:10982445

  18. 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

  19. 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.

  20. 4.0-Å resolution cryo-EM structure of the mammalian chaperonin TRiC/CCT reveals its unique subunit arrangement

    PubMed Central

    Cong, Yao; Baker, Matthew L.; Jakana, Joanita; Woolford, David; Miller, Erik J.; Reissmann, Stefanie; Kumar, Ramya N.; Redding-Johanson, Alyssa M.; Batth, Tanveer S.; Mukhopadhyay, Aindrila; Ludtke, Steven J.; Frydman, Judith; Chiu, Wah

    2010-01-01

    The essential double-ring eukaryotic chaperonin TRiC/CCT (TCP1-ring complex or chaperonin containing TCP1) assists the folding of ∼5–10% of the cellular proteome. Many TRiC substrates cannot be folded by other chaperonins from prokaryotes or archaea. These unique folding properties are likely linked to TRiC’s unique heterooligomeric subunit organization, whereby each ring consists of eight different paralogous subunits in an arrangement that remains uncertain. Using single particle cryo-EM without imposing symmetry, we determined the mammalian TRiC structure at 4.7-Å resolution. This revealed the existence of a 2-fold axis between its two rings resulting in two homotypic subunit interactions across the rings. A subsequent 2-fold symmetrized map yielded a 4.0-Å resolution structure that evinces the densities of a large fraction of side chains, loops, and insertions. These features permitted unambiguous identification of all eight individual subunits, despite their sequence similarity. Independent biochemical near-neighbor analysis supports our cryo-EM derived TRiC subunit arrangement. We obtained a Cα backbone model for each subunit from an initial homology model refined against the cryo-EM density. A subsequently optimized atomic model for a subunit showed ∼95% of the main chain dihedral angles in the allowable regions of the Ramachandran plot. The determination of the TRiC subunit arrangement opens the way to understand its unique function and mechanism. In particular, an unevenly distributed positively charged wall lining the closed folding chamber of TRiC differs strikingly from that of prokaryotic and archaeal chaperonins. These interior surface chemical properties likely play an important role in TRiC’s cellular substrate specificity. PMID:20194787

  1. 4.0-A resolution cryo-EM structure of the mammalian chaperonin TRiC/CCT reveals its unique subunit arrangement.

    PubMed

    Cong, Yao; Baker, Matthew L; Jakana, Joanita; Woolford, David; Miller, Erik J; Reissmann, Stefanie; Kumar, Ramya N; Redding-Johanson, Alyssa M; Batth, Tanveer S; Mukhopadhyay, Aindrila; Ludtke, Steven J; Frydman, Judith; Chiu, Wah

    2010-03-16

    The essential double-ring eukaryotic chaperonin TRiC/CCT (TCP1-ring complex or chaperonin containing TCP1) assists the folding of approximately 5-10% of the cellular proteome. Many TRiC substrates cannot be folded by other chaperonins from prokaryotes or archaea. These unique folding properties are likely linked to TRiC's unique heterooligomeric subunit organization, whereby each ring consists of eight different paralogous subunits in an arrangement that remains uncertain. Using single particle cryo-EM without imposing symmetry, we determined the mammalian TRiC structure at 4.7-A resolution. This revealed the existence of a 2-fold axis between its two rings resulting in two homotypic subunit interactions across the rings. A subsequent 2-fold symmetrized map yielded a 4.0-A resolution structure that evinces the densities of a large fraction of side chains, loops, and insertions. These features permitted unambiguous identification of all eight individual subunits, despite their sequence similarity. Independent biochemical near-neighbor analysis supports our cryo-EM derived TRiC subunit arrangement. We obtained a Calpha backbone model for each subunit from an initial homology model refined against the cryo-EM density. A subsequently optimized atomic model for a subunit showed approximately 95% of the main chain dihedral angles in the allowable regions of the Ramachandran plot. The determination of the TRiC subunit arrangement opens the way to understand its unique function and mechanism. In particular, an unevenly distributed positively charged wall lining the closed folding chamber of TRiC differs strikingly from that of prokaryotic and archaeal chaperonins. These interior surface chemical properties likely play an important role in TRiC's cellular substrate specificity. PMID:20194787

  2. A eukaryotic cytosolic chaperonin is associated with a high molecular weight intermediate in the assembly of hepatitis B virus capsid, a multimeric particle

    PubMed Central

    1994-01-01

    We have established a system for assembly of hepatitis B virus capsid, a homomultimer of the viral core polypeptide, using cell-free transcription-linked translation. The mature particles that are produced are indistinguishable from authentic viral capsids by four criteria: velocity sedimentation, buoyant density, protease resistance, and electron microscopic appearance. Production of unassembled core polypeptides can be uncoupled from production of capsid particles by decreasing core mRNA concentration. Addition of excess unlabeled core polypeptides allows the chase of the unassembled polypeptides into mature capsids. Using this cell-free system, we demonstrate that assembly of capsids proceeds by way of a novel high molecular weight intermediate. Upon isolation, the high molecular weight intermediate is productive of mature capsids when energy substrates are manipulated. A 60-kD protein related to the chaperonin t-complex polypeptide 1 (TCP-1) is found in association with core polypeptides in two different assembly intermediates, but is not associated with either the initial unassembled polypeptides or with the final mature capsid product. These findings implicate TCP-1 or a related chaperonin in viral assembly and raise the possibility that eukaryotic cytosolic chaperonins may play a distinctive role in multimer assembly apart from their involvement in assisting monomer folding. PMID:7908022

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

    PubMed

    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. PMID:27630992

  4. 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. PMID:27630992

  5. Ideals and compromises in palliative care.

    PubMed

    Philip, Jennifer A M; Komesaroff, Paul

    2006-12-01

    This qualitative study explores the concept of ideal palliative care as it broadens its field of application from terminal care to include people earlier in the course of an illness. Focus groups were held with palliative care professionals from community, inpatient, and hospital consultancy services to examine this issue. Palliative care professionals have clear views of what constitutes ideal care that include: establishing a relationship, setting goals, communication, acceptance, advocacy, flexibility, symptom relief, and recognising the identity of each person. There was agreement upon the nature of obstacles that prevented ideal care being achieved including obstacles created by families, other health professionals, administrative structures, and conflicts between the aims of care for a particular patient. Finally each clinician has a well-developed set of personal views of the acceptable limits to practice, although these views vary widely. The clusters of ideas emerging in this study describe three objects of different ontologic status. The elements of ideal care are conceptual in nature, highlighting the aspirations for workers. The obstacles reflect the real world that palliative care professionals must negotiate each day, giving rise to a form of care that was good enough. The acceptable standards and their limits is the degree to which staff will or will not accept the compromises in care raised by the real world of practice, reflecting the ethical stance of the workers. The pursuit of ideal care may be motivated by a complex mix of aspirations, real-world practicalities and fulfilment for both patients and staff.

  6. 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

  7. Catholic hospitals: survival without moral compromise.

    PubMed

    Pellegrino, E D

    1985-05-01

    The three overriding challenges facing Catholic hospitals today are the decline in vocations, commercialization through competition, and the moral pluralism of participatory democracy. These problems lead to a single practical question: How can Catholic health care institutions preserve their integrity while surviving in today's fiscal and moral climate? Cooperation throughout the entire Catholic health care ministry is essential. Either the whole Catholic community will cooperate and make sacrifices to confront the eroding forces in a specifically Christian way, or the authenticity of the Church's healing ministry will gradually be compromised into extinction. As a unified entity, the Catholic community could more than adequately address the challenges facing it. The obstacles to a cooperative effort of this magnitude are obvious--community and professional pride, regional rivalries, differences of mission among sponsoring religious institutes, and natural resistance to central planning and organization. Today's exigencies are created less by a scarcity of resources than by a disinclination to share them. The problems are more complicated than they were 40 years ago, but the Catholic community also has more resources than then--more people, more money, more organizational and informational skills. We can do more with far less sacrifice than ever before in history. And to do so would offer the world a highly convincing evangelical message. PMID:10271498

  8. 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

  9. Purification, crystallization, and preliminary X-ray crystallographic analysis of the Group III chaperonin from Carboxydothermus hydrogenoformans.

    PubMed

    An, Young Jun; Rowland, Sara E; Robb, Frank T; Cha, Sun-Shin

    2016-06-01

    Chaperonins (CPNs) are megadalton sized ATP-dependent nanomachines that facilitate protein folding through complex cycles of complex allosteric articulation. They consist of two back-to-back stacked multisubunit rings. CPNs are usually classified into Group I and Group II. Here, we report the crystallization of both the AMPPNP (an ATP analogue) and ADP bound forms of a novel CPN, classified as belonging to a third Group, recently discovered in the extreme thermophile Carboxydothermus hydrogenoformans. Crystals of the two forms were grown by the vapor batch crystallization method at 295 K. Crystals of the Ch-CPN/AMPPNP complex diffracted to 3.0 Å resolution and belonged to the space group P422, with unit-cell parameters a = b = 186.166, c = 160.742 Å. Assuming the presence of four molecules in the asymmetric unit, the solvent content was estimated to be about 60.02%. Crystals of the Ch-CPN/ADP complex diffracted to 4.0 Å resolution and belonged to the space group P4212, with unit-cell parameters a = b = 209.780, c = 169.813Å. Assuming the presence of four molecules in the asymmetric unit, the solvent content was estimated to be about 70.19%.

  10. 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.

  11. 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

  12. 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

  13. Chaperonin TRiC/CCT Modulates the Folding and Activity of Leukemogenic Fusion Oncoprotein AML1-ETO.

    PubMed

    Roh, Soung-Hun; Kasembeli, Moses; Galaz-Montoya, Jesús G; Trnka, Mike; Lau, Wilson Chun-Yu; Burlingame, Alma; Chiu, Wah; Tweardy, David J

    2016-02-26

    AML1-ETO is the most common fusion oncoprotein causing acute myeloid leukemia (AML), a disease with a 5-year survival rate of only 24%. AML1-ETO functions as a rogue transcription factor, altering the expression of genes critical for myeloid cell development and differentiation. Currently, there are no specific therapies for AML1-ETO-positive AML. While known for decades to be the translational product of a chimeric gene created by the stable chromosome translocation t(8;21)(q22;q22), it is not known how AML1-ETO achieves its native and functional conformation or whether this process can be targeted for therapeutic benefit. Here, we show that the biosynthesis and folding of the AML1-ETO protein is facilitated by interaction with the essential eukaryotic chaperonin TRiC (or CCT). We demonstrate that a folding intermediate of AML1-ETO binds to TRiC directly, mainly through its β-strand rich, DNA-binding domain (AML-(1-175)), with the assistance of HSP70. Our results suggest that TRiC contributes to AML1-ETO proteostasis through specific interactions between the oncoprotein's DNA-binding domain, which may be targeted for therapeutic benefit.

  14. 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

  15. 47 CFR 1.1915 - Exploration of compromise.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... submitted in writing with full justification of the offer and addressing the bases for compromise at 31 CFR... effect compromise, preferably during the course of personal interviews, in accordance with the standards set forth in part 902 of the Federal Claims Collection Standards (31 CFR part 902). The...

  16. 5 CFR 1312.30 - Loss or possible compromise.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 3 2014-01-01 2014-01-01 false Loss or possible compromise. 1312.30 Section 1312.30 Administrative Personnel OFFICE OF MANAGEMENT AND BUDGET OMB DIRECTIVES CLASSIFICATION... Classified Information § 1312.30 Loss or possible compromise. Any person who has knowledge of the loss...

  17. 5 CFR 1312.30 - Loss or possible compromise.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 3 2013-01-01 2013-01-01 false Loss or possible compromise. 1312.30 Section 1312.30 Administrative Personnel OFFICE OF MANAGEMENT AND BUDGET OMB DIRECTIVES CLASSIFICATION... Classified Information § 1312.30 Loss or possible compromise. Any person who has knowledge of the loss...

  18. 26 CFR 300.3 - Offer to compromise fee.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... taxpayer if the offer is accepted, rejected, withdrawn, or returned as nonprocessable after acceptance for... 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...

  19. 41 CFR 105-55.020 - Bases for compromise.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Bases for compromise. 105-55.020 Section 105-55.020 Public Contracts and Property Management Federal Property Management... Administration 55-COLLECTION OF CLAIMS OWED THE UNITED STATES § 105-55.020 Bases for compromise. (a) The...

  20. 41 CFR 105-55.020 - Bases for compromise.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Bases for compromise. 105-55.020 Section 105-55.020 Public Contracts and Property Management Federal Property Management... Administration 55-COLLECTION OF CLAIMS OWED THE UNITED STATES § 105-55.020 Bases for compromise. (a) The...

  1. 41 CFR 105-55.020 - Bases for compromise.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Bases for compromise. 105-55.020 Section 105-55.020 Public Contracts and Property Management Federal Property Management... Administration 55-COLLECTION OF CLAIMS OWED THE UNITED STATES § 105-55.020 Bases for compromise. (a) The...

  2. 41 CFR 105-55.020 - Bases for compromise.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Bases for compromise. 105-55.020 Section 105-55.020 Public Contracts and Property Management Federal Property Management... Administration 55-COLLECTION OF CLAIMS OWED THE UNITED STATES § 105-55.020 Bases for compromise. (a) The...

  3. 41 CFR 105-55.020 - Bases for compromise.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Bases for compromise. 105-55.020 Section 105-55.020 Public Contracts and Property Management Federal Property Management... Administration 55-COLLECTION OF CLAIMS OWED THE UNITED STATES § 105-55.020 Bases for compromise. (a) The...

  4. 20 CFR 340.13 - Compromise of amounts recoverable.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Compromise of amounts recoverable. 340.13 Section 340.13 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT RECOVERY OF BENEFITS § 340.13 Compromise of amounts recoverable. The Board or its designee...

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

    PubMed Central

    Gheorghiu, IM; Stoian, IM

    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. Abbreviations: healthy compromised patients = HCP PMID:25870664

  6. 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...

  7. 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...

  8. 12 CFR 308.545 - Compromise or settlement.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 5 2013-01-01 2013-01-01 false Compromise or settlement. 308.545 Section 308.545 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION PROCEDURE AND RULES OF PRACTICE RULES OF PRACTICE AND PROCEDURE Program Fraud Civil Remedies and Procedures § 308.545 Compromise or settlement....

  9. 12 CFR 308.545 - Compromise or settlement.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 5 2012-01-01 2012-01-01 false Compromise or settlement. 308.545 Section 308.545 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION PROCEDURE AND RULES OF PRACTICE RULES OF PRACTICE AND PROCEDURE Program Fraud Civil Remedies and Procedures § 308.545 Compromise or settlement....

  10. 12 CFR 308.545 - Compromise or settlement.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 4 2011-01-01 2011-01-01 false Compromise or settlement. 308.545 Section 308.545 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION PROCEDURE AND RULES OF PRACTICE RULES OF PRACTICE AND PROCEDURE Program Fraud Civil Remedies and Procedures § 308.545 Compromise or settlement....

  11. 12 CFR 308.545 - Compromise or settlement.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 5 2014-01-01 2014-01-01 false Compromise or settlement. 308.545 Section 308.545 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION PROCEDURE AND RULES OF PRACTICE RULES OF PRACTICE AND PROCEDURE Program Fraud Civil Remedies and Procedures § 308.545 Compromise or settlement....

  12. 12 CFR 308.545 - Compromise or settlement.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Compromise or settlement. 308.545 Section 308.545 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION PROCEDURE AND RULES OF PRACTICE RULES OF PRACTICE AND PROCEDURE Program Fraud Civil Remedies and Procedures § 308.545 Compromise or settlement....

  13. 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.

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

    PubMed

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

    2015-10-01

    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.

  15. 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

  16. 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

  17. 32 CFR 2400.33 - Loss or possible compromise.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 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...

  18. 32 CFR 2400.33 - Loss or possible compromise.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 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...

  19. 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,...

  20. 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,...

  1. 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,...

  2. 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,...

  3. 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,...

  4. 20 CFR 340.13 - Compromise of amounts recoverable.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... INSURANCE ACT RECOVERY OF BENEFITS § 340.13 Compromise of amounts recoverable. The Board or its designee may... recoverable may not be considered in any case in which there is an indication of fraud, the presentation of...

  5. 20 CFR 340.13 - Compromise of amounts recoverable.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... INSURANCE ACT RECOVERY OF BENEFITS § 340.13 Compromise of amounts recoverable. The Board or its designee may... recoverable may not be considered in any case in which there is an indication of fraud, the presentation of...

  6. 20 CFR 340.13 - Compromise of amounts recoverable.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... INSURANCE ACT RECOVERY OF BENEFITS § 340.13 Compromise of amounts recoverable. The Board or its designee may... recoverable may not be considered in any case in which there is an indication of fraud, the presentation of...

  7. One member of a gro-ESL-like chaperonin multigene family in Bradyrhizobium japonicum is co-regulated with symbiotic nitrogen fixation genes.

    PubMed Central

    Fischer, H M; Babst, M; Kaspar, T; Acuña, G; Arigoni, F; Hennecke, H

    1993-01-01

    This report is concerned with the structural characterization and genetic regulation of new bacterial groES and groEL chaperonin genes, and presents two novelties. The first is the discovery that the nitrogen fixing soybean root nodule bacterium, Bradyrhizobium japonicum, unlike all other prokaryotes investigated so far, possesses a multigene family consisting of five very similar, though not identical, groESL-like genes. The second novelty relates to the finding that these five homologues are expressed to different degrees and, in particular, that one family member (namely groESL3) is induced by a mechanism that does not involve the well-known heat shock response. By contrast, the groESL3 genes are co-regulated together with symbiotic nitrogen fixation genes, in that they are activated by the nitrogen fixation regulatory protein NifA at low oxygen conditions and transcribed from a -24/-12 promoter by the sigma 54 RNA polymerase. Two other members of the groESL gene family are apparently expressed constitutively at different levels, and yet another one is strongly induced by high temperature. As an attractive hypothesis it follows that B. japonicum may modulate its cellular contents of GroES- and GroEL-like chaperonins in response to specific environmental conditions and physiological needs. Images PMID:8101485

  8. Identification of in vivo substrates of the yeast mitochondrial chaperonins reveals overlapping but non-identical requirement for hsp60 and hsp10.

    PubMed Central

    Dubaquié, Y; Looser, R; Fünfschilling, U; Jenö, P; Rospert, S

    1998-01-01

    The mechanism of chaperonin-assisted protein folding has been mostly analyzed in vitro using non-homologous substrate proteins. In order to understand the relative importance of hsp60 and hsp10 in the living cell, homologous substrate proteins need to be identified and analyzed. We have devised a novel screen to test the folding of a large variety of homologous substrates in the mitochondrial matrix in the absence or presence of functional hsp60 or hsp10. The identified substrates have an Mr of 15-90 kDa and fall into three groups: (i) proteins that require both hsp60 and hsp10 for correct folding; (ii) proteins that completely fail to fold after inactivation of hsp60 but are unaffected by the inactivation of hsp10; and (iii) newly imported hsp60 itself, which is more severely affected by inactivation of hsp10 than by inactivation of pre-existing hsp60. The majority of the identified substrates are group I proteins. For these, the lack of hsp60 function has a more pronounced effect than inactivation of hsp10. We suggest that homologous substrate proteins have differential chaperonin requirements, indicating that hsp60 and hsp10 do not always act as a single functional unit in vivo. PMID:9774331

  9. 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

  10. 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

  11. Chaperonin CCT-mediated AIB1 folding promotes the growth of ERα-positive breast cancer cells on hard substrates.

    PubMed

    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. 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.

  13. Roles of Melatonin in Fetal Programming in Compromised Pregnancies

    PubMed Central

    Chen, Yu-Chieh; Sheen, Jiunn-Ming; Tiao, Miao-Meng; Tain, You-Lin; Huang, Li-Tung

    2013-01-01

    Compromised pregnancies such as those associated with gestational diabetes mellitus, intrauterine growth retardation, preeclampsia, maternal undernutrition, and maternal stress may negatively affect fetal development. Such pregnancies may induce oxidative stress to the fetus and alter fetal development through the epigenetic process that may affect development at a later stage. Melatonin is an oxidant scavenger that reverses oxidative stress during the prenatal period. Moreover, the role of melatonin in epigenetic modifications in the field of developmental programming has been studied extensively. Here, we describe the physiological function of melatonin in pregnancy and discuss the roles of melatonin in fetal programming in compromised pregnancies, focusing on its involvement in redox and epigenetic mechanisms. PMID:23466884

  14. Function of the maize mitochondrial chaperonin hsp60: specific association between hsp60 and newly synthesized F1-ATPase alpha subunits.

    PubMed

    Prasad, T K; Hack, E; Hallberg, R L

    1990-08-01

    Mitochondria contain a protein, hsp60, that is induced by heat shock and has been shown to function as a chaperonin in the assembly of mitochondrial enzyme complexes composed of proteins encoded by nuclear genes and imported from the cytosol. To determine whether products of mitochondrial genes are also assembled through an interaction with hsp60, we looked for association between hsp60 and proteins synthesized by isolated mitochondria. We have determined by electrophoretic, centrifugal, and immunological assays that at least two of those proteins become physically associated with hsp60. In mitochondrial matrix extracts, this association could be disrupted by the addition of Mg-ATP. One of the proteins that formed a stable association with hsp60 was the alpha subunit of the multicomponent complex F1-ATPase. We have not identified the other protein. These results indicate that hsp60 can function in the folding and assembly of mitochondrial proteins encoded by both mitochondrial and nuclear genes.

  15. 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

  16. 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

  17. Effects of C-terminal Truncation of Chaperonin GroEL on the Yield of In-cage Folding of the Green Fluorescent Protein*

    PubMed Central

    Ishino, So; Kawata, Yasushi; Taguchi, Hideki; Kajimura, Naoko; Matsuzaki, Katsumi; Hoshino, Masaru

    2015-01-01

    Chaperonin GroEL from Escherichia coli consists of two heptameric rings stacked back-to-back to form a cagelike structure. It assists in the folding of substrate proteins in concert with the co-chaperonin GroES by incorporating them into its large cavity. The mechanism underlying the incorporation of substrate proteins currently remains unclear. The flexible C-terminal residues of GroEL, which are invisible in the x-ray crystal structure, have recently been suggested to play a key role in the efficient encapsulation of substrates. These C-terminal regions have also been suggested to separate the double rings of GroEL at the bottom of the cavity. To elucidate the role of the C-terminal regions of GroEL on the efficient encapsulation of substrate proteins, we herein investigated the effects of C-terminal truncation on GroE-mediated folding using the green fluorescent protein (GFP) as a substrate. We demonstrated that the yield of in-cage folding mediated by a single ring GroEL (SR1) was markedly decreased by truncation, whereas that mediated by a double ring football-shaped complex was not affected. These results suggest that the C-terminal region of GroEL functions as a barrier between rings, preventing the leakage of GFP through the bottom space of the cage. We also found that once GFP folded into its native conformation within the cavity of SR1 it never escaped even in the absence of the C-terminal tails. This suggests that GFP molecules escaped through the pore only when they adopted a denatured conformation. Therefore, the folding and escape of GFP from C-terminally truncated SR1·GroES appeared to be competing with each other. PMID:25887400

  18. Mycobacterium tuberculosis Chaperonin 10 Is Secreted in the Macrophage Phagosome: Is Secretion Due to Dissociation and Adoption of a Partially Helical Structure at the Membrane?

    PubMed Central

    Fossati, Gianluca; Izzo, Gaetano; Rizzi, Emanuele; Gancia, Emanuela; Modena, Daniela; Moras, Maria Luisa; Niccolai, Neri; Giannozzi, Elena; Spiga, Ottavia; Bono, Letizia; Marone, Piero; Leone, Eugenio; Mangili, Francesca; Harding, Stephen; Errington, Neil; Walters, Christopher; Henderson, Brian; Roberts, Michael M.; Coates, Anthony R. M.; Casetta, Bruno; Mascagni, Paolo

    2003-01-01

    To confirm that Mycobacterium tuberculosis chaperonin 10 (Cpn10) is secreted outside the live bacillus, infected macrophages were examined by electron microscopy. This revealed that the mycobacterial protein accumulates both in the wall of the bacterium and in the matrix of the phagosomes in which ingested mycobacteria survive within infected macrophages. To understand the structural implications underlying this secretion, a structural study of M. tuberculosis Cpn10 was performed under conditions that are generally believed to mimic the membrane environment. It was found that in buffer-organic solvent mixtures, the mycobacterial protein forms two main species, namely, a partially helical monomer that prevails in dilute solutions at room temperature and a dimer that folds into a β-sheet-dominated structure and prevails in either concentrated protein solutions at room temperature or in dilute solutions at low temperature. A partially helical monomer was also found and was completely associated with negatively charged detergents in a micelle-bound state. Remarkably, zwitterionic lipids had no effect on the protein structure. By using N- and C-truncated forms of the protein, the C- and N-terminal sequences were identified as possessing an amphiphilic helical character and as selectively associating with acidic detergent micelles. When the study was extended to other chaperonins, it was found that human Cpn10 is also monomeric and partially helical in dilute organic solvent-buffer mixtures. In contrast, Escherichia coli Cpn10 is mostly dimeric and predominately β-sheet in both dilute and concentrated solutions. Interestingly, human Cpn10 also crosses biological membranes, whereas the E. coli homologue is strictly cytosolic. These results suggest that dissociation to partially helical monomers and interaction with acidic lipids may be two important steps in the mechanism of secretion of M. tuberculosis Cpn10 to the external environment. PMID:12837802

  19. 14 CFR 1261.414 - Compromise of claims.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ....414 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION PROCESSING OF MONETARY CLAIMS... activities of the agency where the claim, exclusive of interest, penalties, and administrative costs, does... administrative costs, exceeds $20,000, the authority to accept the compromise rests solely with the Department...

  20. 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...

  1. Enacting the Primary Grade Curriculum: Contradiction, Conflict, and Compromise.

    ERIC Educational Resources Information Center

    Goldstein, Lisa S.

    Although bound by tradition and physical location to elementary schooling, the primary grades are also considered the capstone experience of early childhood education. Primary grade teachers are required to bridge these two disparate worlds, constantly mediating, negotiating, translating, and compromising. This paper describes the experience of…

  2. 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…

  3. 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.

  4. 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... the loss or possible compromise of classified information shall immediately report the...

  5. 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...

  6. 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...

  7. 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.

  8. Tissue response: biomaterials, dental implants, and compromised osseous tissue.

    PubMed

    Babu RS, Arvind; Ogle, Orrett

    2015-04-01

    Tissue response represents an important feature in biocompatibility in implant procedures. This review article highlights the fundamental characteristics of tissue response after the implant procedure. This article also highlights the tissue response in compromised osseous conditions. Understanding the histologic events after dental implants in normal and abnormal bone reinforces the concept of case selection in dental implants.

  9. 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...

  10. 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...

  11. 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...

  12. 49 CFR 107.327 - Compromise and settlement.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... outstanding. (ii) If a compromise is agreed to by the parties, the respondent is notified in writing. Upon receipt of payment by Office of Chief Counsel, the respondent is notified in writing that acceptance of payment is in full satisfaction of the civil penalty proposed or assessed, and Office of Chief...

  13. 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…

  14. 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.

  15. 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.

  16. The ethics of moral compromise for stem cell research policy.

    PubMed

    Master, Zubin; Crozier, G K D

    2012-03-01

    In the US, stem cell research is at a moral impasse-many see this research as ethically mandated due to its potential for ameliorating major diseases, while others see this research as ethically impermissible because it typically involves the destruction of embryos and use of ova from women. Because their creation does not require embryos or ova, induced pluripotent stem cells offer the most promising path for addressing the main ethical objections to stem cell research; however, this technology is still in development. In order for scientists to advance induced pluripotent stem cell research to a point of translational readiness, they must continue to use ova and embryos in the interim. How then are we to ethically move forward with stem cell research? We argue that there is personal integrity and value in adopting a 'moral compromise' as a means for moving past the moral impasse in stem cell research. In a moral compromise, each party concedes part of their desired outcome in order to engage in a process that respects the values and desires of all parties equitably. Whereas some contend that moral compromise in stem cell research necessarily involves self-contradiction or loss of personal integrity, we argue that in the US context, stem cell research satisfies many of the key pre-conditions of an effective moral compromise. To illustrate our point, we offer a model solution wherein eggs and embryos are temporarily used until non-egg and non-embryonic sources of pluripotent stem cells are developed to a state of translational readiness.

  17. Congenital Microstomia in a Neonate with Impending Respiratory Compromise

    PubMed Central

    Nguyen, Khoa N.; Semenov, Igor; Blasiole, Brian; Robison, Jacob G.; Chi, David H.

    2014-01-01

    Microstomia is the term used to describe a reduction in the size of the oral aperture that is severe enough to compromise quality of life, nutrition, and cosmesis. Few cases of congenital microstomia have been reported as most microstomia cases are due to burn injuries. We are presenting a case of a neonate who was found to be in respiratory distress with severe congenital microstomia from no known cause. This case illustrates the rarity of this type of pathologic anatomy as well as the teamwork and tools necessary to treat these patients. PMID:25610661

  18. 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.

  19. 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

  20. Effects of the chaperonin GroE on the refolding of tryptophanase from Escherichia coli. Refolding is enhanced in the presence of ADP.

    PubMed

    Mizobata, T; Akiyama, Y; Ito, K; Yumoto, N; Kawata, Y

    1992-09-01

    The refolding of the tetrameric enzyme tryptophanase was facilitated by the chaperonin GroE. Maximum refolding yield of tryptophanase molecules (about 80%) was attained in the presence of a 15-fold excess of GroE 21-mer over tryptophanase monomer. The GroEL subunit was required for this improvement in refolding yield, whereas the GroES subunit was not. Light scattering experiments of the refolding reaction revealed that GroE bound to tryptophanase folding intermediates and suppressed their aggregation. The presence of ATP was required for the efficient dissociation of tryptophanase from GroEL. However, our experiments indicated that tryptophanase dissociated readily from GroEL in the presence of not only ATP, but also in the presence of non-hydrolyzable ATP analogues such as ATP gamma S (adenosine 5'-O-(3-thiotriphosphate)) and AMP-PNP (adenyl-5'-yl imidodiphosphate) as well. Surprisingly, the release of tryptophanase from GroEL was facilitated in the presence of ADP as well. We concluded that the binding of nucleotides such as ATP and ADP changed the conformation of GroEL and facilitated the dissociation of tryptophanase molecules. The conformation formed in the presence of ADP was distinct from the conformation formed in the presence of ATP, as shown by the selective dissociation of various folding proteins from the two conformations.

  1. 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

  2. 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.

  3. Chaperonin-containing t-complex protein-1 subunit β as a possible biomarker for the phase of glomerular hyperfiltration of diabetic nephropathy.

    PubMed

    Wu, Chung-Ze; Chang, Li-Chien; Lin, Yuh-Feng; Hung, Yi-Jen; Pei, Dee; Chen, Jin-Shuen

    2015-01-01

    In cell model, we discovered the association between chaperonin-containing t-complex polypeptide 1 subunit β (TCP-1β) and early diabetic nephropathy (DN). In this study, we further explored the relationships between TCP-1β and type 2 diabetic mellitus (DM). To mimic the clinical hyperfiltration state, a type 2 DM mice model was established by feeding a high-fat diet in combination with treatment of streptozotocin and nicotinamide. Blood and urine were collected to determine creatinine clearance (C cr), and kidney tissues were harvested for evaluation of TCP-1β expression by immunohistochemistry and Western blot. Meanwhile, clinical subjects of healthy controls and type 2 DM were recruited to strengthen the evidence with urine TCP-1β. Results showed that C cr and the expression of TCP-1β in kidney were significantly higher one week after hyperglycemia development, suggesting that the hyperfiltration state was successfully established in the mice model. TCP-1β was expressed predominantly on renal tubules. By using the estimated glomerular filtration rate to index progression in clinical investigation, urine TCP-1β level was associated with the hyperfiltration phase in type 2 DM patients. Conclusively, we confirmed that TCP-1β is a possible biomarker for early nephropathy of type 2 DM, but further mechanistic study to elucidate its cause and pathway is needed.

  4. 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…

  5. 15 CFR 19.7 - When will Commerce entities compromise a Commerce debt?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... COMMERCE DEBT COLLECTION Procedures To Collect Commerce Debts § 19.7 When will Commerce entities compromise... Commerce entity may compromise the Commerce debt in accordance with the provisions of 31 CFR part 902 and the Commerce entity's policies and procedures. Legal counsel approval to compromise a Commerce debt...

  6. 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…

  7. 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...

  8. 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...

  9. 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.

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

    DOE PAGES

    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

  11. 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.

  12. 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

  13. 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

  14. 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

  15. Mitigating reptile road mortality: fence failures compromise ecopassage effectiveness.

    PubMed

    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

  16. 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

  17. 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

  18. Mitigating reptile road mortality: fence failures compromise ecopassage effectiveness.

    PubMed

    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. 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

  20. Stepwise chilling: tender pork without compromising water-holding capacity.

    PubMed

    Rosenvold, K; Borup, U; Therkildsen, M

    2010-05-01

    The current pork slaughter process is primarily optimized to reduce cooler shrink and the incidence of PSE pork. Elimination of the halothane gene and improved preslaughter handling have decreased the incidence of PSE pork and improved the water-holding capacity of the muscle; however, the chilling process has not been optimized to accommodate these changes. The hypothesis that stepwise chilling could improve tenderness without compromising water-holding capacity was tested in this study. The stepwise chilling treatments were composed of a rapid chilling to 10 or 15 degrees C (in a chilling tunnel) and a 6-h holding period at 10 or 15 degrees C, followed by rapid chilling to 4 degrees C. Both treatments were compared directly with a chilling treatment that simulated conventional tunnel chilling; one carcass half from each pig was allocated to a stepwise chilling treatment, whereas the other carcass half was allocated to the control treatment. A total of 42 pigs were slaughtered on 6 slaughter days. Biopsies were collected for analysis of glycogen degradation and glycogen debranching enzyme activity from slaughter until 72 h postmortem, and samples for color, sarcomere length, drip loss, Warner-Bratzler shear force, and sensory analysis were removed from the carcass 24 h postmortem. Substantial temperature differences were obtained during the holding period between the stepwise and conventionally chilled carcass halves. These had almost, but not completely, disappeared by 22 h postmortem, and although the differences were small, pH was significantly (P < 0.01) less in the stepwise-chilled carcasses compared with the control carcasses. The stepwise chilling treatments led to significantly improved (P < 0.01) tenderness in LM without compromising quality indicators or attributes such as pH, drip loss, or ham processing yield, although color of the stepwise-chilled pork was affected. Neither the tenderness of processed semimembranosus muscle nor the shear force of

  1. 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

  2. Effects of a Mutation in the HSPE1 Gene Encoding the Mitochondrial Co-chaperonin HSP10 and Its Potential Association with a Neurological and Developmental Disorder

    PubMed Central

    Bie, Anne S.; Fernandez-Guerra, Paula; Birkler, Rune I. D.; Nisemblat, Shahar; Pelnena, Dita; Lu, Xinping; Deignan, Joshua L.; Lee, Hane; Dorrani, Naghmeh; Corydon, Thomas J.; Palmfeldt, Johan; Bivina, Liga; Azem, Abdussalam; Herman, Kristin; Bross, Peter

    2016-01-01

    We here report molecular investigations of a missense mutation in the HSPE1 gene encoding the HSP10 subunit of the HSP60/ HSP10 chaperonin complex that assists protein folding in the mitochondrial matrix. The mutation was identified in an infant who came to clinical attention due to infantile spasms at 3 months of age. Clinical exome sequencing revealed heterozygosity for a HSPE1 NM_002157.2:c.217C>T de novo mutation causing replacement of leucine with phenylalanine at position 73 of the HSP10 protein. This variation has never been observed in public exome sequencing databases or the literature. To evaluate whether the mutation may be disease-associated we investigated its effects by in vitro and ex vivo studies. Our in vitro studies indicated that the purified mutant protein was functional, yet its thermal stability, spontaneous refolding propensity, and resistance to proteolytic treatment were profoundly impaired. Mass spectrometric analysis of patient fibroblasts revealed barely detectable levels of HSP10-p.Leu73Phe protein resulting in an almost 2-fold decrease of the ratio of HSP10 to HSP60 subunits. Amounts of the mitochondrial superoxide dismutase SOD2, a protein whose folding is known to strongly depend on the HSP60/HSP10 complex, were decreased to approximately 20% in patient fibroblasts in spite of unchanged SOD2 transcript levels. As a likely consequence, mitochondrial superoxide levels were increased about 2-fold. Although, we cannot exclude other causative or contributing factors, our experimental data support the notion that the HSP10-p.Leu73Phe mutation could be the cause or a strong contributing factor for the disorder in the described patient. PMID:27774450

  3. Chaperonin-containing T-complex Protein 1 Subunit ζ Serves as an Autoantigen Recognized by Human Vδ2 γδ T Cells in Autoimmune Diseases.

    PubMed

    Chen, Hui; You, Hongqin; Wang, Lifang; Zhang, Xuan; Zhang, Jianmin; He, Wei

    2016-09-16

    Human γδ T cells recognize conserved endogenous and stress-induced antigens typically associated with autoimmune diseases. However, the role of γδ T cells in autoimmune diseases is not clear. Few autoimmune disease-related antigens recognized by T cell receptor (TCR) γδ have been defined. In this study, we compared Vδ2 TCR complementarity-determining region 3 (CDR3) between systemic lupus erythematosus (SLE) patients and healthy donors. Results show that CDR3 length distribution differed significantly and displayed oligoclonal characteristics in SLE patients when compared with healthy donors. We found no difference in the frequency of Jδ gene fragment usage between these two groups. According to the dominant CDR3δ sequences in SLE patients, synthesized SL2 peptides specifically bound to human renal proximal tubular epithelial cell line HK-2; SL2-Vm, a mutant V sequence of SL2, did not bind. We identified the putative protein ligand chaperonin-containing T-complex protein 1 subunit ζ (CCT6A) using SL2 as a probe in HK-2 cell protein extracts by affinity chromatography and liquid chromatography-electrospray ionization-tandem mass spectrometry analysis. We found CCT6A expression on the surface of HK-2 cells. Cytotoxicity of only Vδ2 γδ T cells to HK-2 cells was blocked by anti-CCT6A antibody. Finally, we note that CCT6A concentration was significantly increased in plasma of SLE and rheumatoid arthritis patients. These data suggest that CCT6A is a novel autoantigen recognized by Vδ2 γδ T cells, which deepens our understanding of mechanisms in autoimmune diseases. PMID:27489109

  4. 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

  5. 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.

  6. [Measures for tuberculosis in compromised hosts--mainly on chemoprophylaxis].

    PubMed

    Yamagishi, Fumio

    2003-10-01

    As for the measures for tuberculosis in Japan, BCG inoculation and chemoprophylaxis have been done with emphasis placed on children and young people. Since, however, about 90% are older than 30 years and more than 50% are older than 60 years among the new TB patients, measures, particularly chemoprophylaxis aiming at the middle-old aged people are needed in the future. We discuss the method to select cases for chemoprophylaxis as to the cases of diabetes, collagen diseases and lung cancer administered corticosteroid preparations as well as the cases of Crohn's disease and rheumatoid arthritis administered anti-TNF-alpha among compromised hosts. In diabetics, chemoprophylaxis is necessary for those who show healing of TB despite there being no history of TB treatment. Where a corticosteroid preparation, more than 10 mg in terms of prednisolone is administered over a long period of time for collagen disease and lung cancer, chemoprophylaxis is necessary for those who show healing of TB despite there being no history of TB treatment and those who are suspected of having TB infection by a tuberculin test. In the cases of Crohn's disease and rheumatoid arthritis administered anti-TNF-alpha, chemoprophylaxis is necessary for those who show healing of TB despite those who are suspected of having TB infection by a tuberculin test. The administration period of INH as chemoprophylaxis should preferably be set at 9 months instead of 6 months hitherto used. PMID:14621575

  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. 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

  10. 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

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

    PubMed

    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

  12. 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

  13. 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…

  14. 27 CFR 70.484 - Offers in compromise of forfeiture liabilities.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... proponent is notified of the acceptance or rejection of the offer. If the offer is rejected, the sum... is notified and the case is closed. Acceptance of an offer in compromise of civil liabilities does not remit criminal liabilities, nor does acceptance of an offer in compromise of criminal...

  15. 27 CFR 70.483 - Offers in compromise of violations of Federal Alcohol Administration Act.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... offers in compromise may submit such offers on Form 5640.2. When the offer is acted upon, the proponent is notified of the acceptance or rejection of the offer. If the offer is rejected, the sum submitted with the offer in compromise is returned to the proponent. If the offer is accepted, the proponent...

  16. 20 CFR 340.14 - Factors due to be considered in a compromise.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Factors due to be considered in a compromise. 340.14 Section 340.14 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT RECOVERY OF BENEFITS § 340.14 Factors due to be considered in a compromise....

  17. 32 CFR 757.6 - Waiver, compromise, and referral of claims.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... accordance with 31 CFR part 904 shall be forwarded through the Judge Advocate General (Claims and Tort... AFFIRMATIVE CLAIMS REGULATIONS Property Damage Claims § 757.6 Waiver, compromise, and referral of claims. (a... 32 National Defense 5 2010-07-01 2010-07-01 false Waiver, compromise, and referral of claims....

  18. 32 CFR 757.6 - Waiver, compromise, and referral of claims.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... accordance with 31 CFR part 904 shall be forwarded through the Judge Advocate General (Claims and Tort... AFFIRMATIVE CLAIMS REGULATIONS Property Damage Claims § 757.6 Waiver, compromise, and referral of claims. (a... 32 National Defense 5 2012-07-01 2012-07-01 false Waiver, compromise, and referral of claims....

  19. 44 CFR 11.15 - Authority to adjust, determine, compromise and settle.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY GENERAL CLAIMS Administrative Claims Under Federal Tort Claims Act § 11.15 Authority to adjust, determine, compromise and settle. (a) The Chief Counsel of FEMA..., compromise, and settle claims under the provisions of section 2672 of title 28, United States Code, and...

  20. 44 CFR 11.15 - Authority to adjust, determine, compromise and settle.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY GENERAL CLAIMS Administrative Claims Under Federal Tort Claims Act § 11.15 Authority to adjust, determine, compromise and settle. (a) The Chief Counsel of FEMA..., compromise, and settle claims under the provisions of section 2672 of title 28, United States Code, and...

  1. 32 CFR 757.6 - Waiver, compromise, and referral of claims.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... accordance with 31 CFR part 904 shall be forwarded through the Judge Advocate General (Claims and Tort... AFFIRMATIVE CLAIMS REGULATIONS Property Damage Claims § 757.6 Waiver, compromise, and referral of claims. (a... 32 National Defense 5 2011-07-01 2011-07-01 false Waiver, compromise, and referral of claims....

  2. 45 CFR 608.2 - Collection, compromise, and use of consumer reporting agencies.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 3 2011-10-01 2011-10-01 false Collection, compromise, and use of consumer...) NATIONAL SCIENCE FOUNDATION CLAIMS COLLECTION AND ADMINISTRATIVE OFFSET § 608.2 Collection, compromise, and use of consumer reporting agencies. (a) Subject to the specific limitations and procedures of 31...

  3. 45 CFR 608.2 - Collection, compromise, and use of consumer reporting agencies.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Collection, compromise, and use of consumer...) NATIONAL SCIENCE FOUNDATION CLAIMS COLLECTION AND ADMINISTRATIVE OFFSET § 608.2 Collection, compromise, and use of consumer reporting agencies. (a) Subject to the specific limitations and procedures of 31...

  4. 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...

  5. 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...

  6. 45 CFR 30.4 - Compromise, waiver, or disposition under other statutes not precluded.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Compromise, waiver, or disposition under other statutes not precluded. 30.4 Section 30.4 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CLAIMS COLLECTION General Provisions § 30.4 Compromise, waiver, or disposition under...

  7. 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...

  8. 7 CFR 1956.68 - Compromise or adjustment without debtor's signature.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... HOUSING SERVICE, RURAL BUSINESS-COOPERATIVE SERVICE, RURAL UTILITIES SERVICE, AND FARM SERVICE AGENCY... Loan Programs and Multi-Family Housing § 1956.68 Compromise or adjustment without debtor's...

  9. 32 CFR 842.99 - Compromise, termination, and suspension of collection.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... insurance coverage should be obtained and included in the claim file). (2) The Government is unable to...) Compromise is not allowable when there may be fraud, misrepresentation, or violation of antitrust laws....

  10. Combating QR-Code-Based Compromised Accounts in Mobile Social Networks

    PubMed Central

    Guo, Dong; Cao, Jian; Wang, Xiaoqi; Fu, Qiang; Li, Qiang

    2016-01-01

    Cyber Physical Social Sensing makes mobile social networks (MSNs) popular with users. However, such attacks are rampant as malicious URLs are spread covertly through quick response (QR) codes to control compromised accounts in MSNs to propagate malicious messages. Currently, there are generally two types of methods to identify compromised accounts in MSNs: one type is to analyze the potential threats on wireless access points and the potential threats on handheld devices’ operation systems so as to stop compromised accounts from spreading malicious messages; the other type is to apply the method of detecting compromised accounts in online social networks to MSNs. The above types of methods above focus neither on the problems of MSNs themselves nor on the interaction of sensors’ messages, which leads to the restrictiveness of platforms and the simplification of methods. In order to stop the spreading of compromised accounts in MSNs effectively, the attacks have to be traced to their sources first. Through sensors, users exchange information in MSNs and acquire information by scanning QR codes. Therefore, analyzing the traces of sensor-related information helps to identify the compromised accounts in MSNs. This paper analyzes the diversity of information sending modes of compromised accounts and normal accounts, analyzes the regularity of GPS (Global Positioning System)-based location information, and introduces the concepts of entropy and conditional entropy so as to construct an entropy-based model based on machine learning strategies. To achieve the goal, about 500,000 accounts of Sina Weibo and about 100 million corresponding messages are collected. Through the validation, the accuracy rate of the model is proved to be as high as 87.6%, and the false positive rate is only 3.7%. Meanwhile, the comparative experiments of the feature sets prove that sensor-based location information can be applied to detect the compromised accounts in MSNs. PMID:27657071

  11. 28 CFR 0.163 - Approval by Solicitor General of action on compromise offers in certain cases.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... on compromise offers in certain cases. 0.163 Section 0.163 Judicial Administration DEPARTMENT OF... on compromise offers in certain cases. In any Supreme Court case the acceptance, recommendation of acceptance, or rejection, under § 0.160, § 0.161, or § 0.162, of a compromise offer by the Assistant...

  12. Central nervous system compromise in primary Sjögren's syndrome.

    PubMed

    Anaya, Juan-Manuel; Villa, Luis A; Restrepo, Lucas; Molina, Jose F; Mantilla, Rubén D; Vargas, Sergio

    2002-08-01

    Central nervous system (CNS) involvement in primary Sjögren's syndrome (SS) is poorly understood, and its frequency as well as its manifestations are subjects of controversy. The current study was undertaken to determine the prevalence and the clinical and immunogenetic characteristics of CNS compromise in a well defined group of patients with primary SS. In this retrospective study, patients fulfilled the European classification criteria. Among 120 patients with primary SS, 3 (2.5%) had CNS compromise (multiple sclerosis-like illness, complicated migraine, and optic neuritis with epilepsy). The CNS involvement coincided with the onset of sicca symptoms in 1 case. All 3 patients carried the human leukocyte antigen (HLA) DQB1*0303 allele and tested positive for anti-Ro antibodies, but not for anti-cardiolipin antibodies. Although rare, CNS compromise in primary SS can be the presenting manifestation of the disease in a few cases, and may be severe and varied. PMID:17041358

  13. Detecting fetal compromise during active labour and managing neonatal after-effects.

    PubMed

    Meredith, Dawn; Hugill, Kevin

    2016-01-01

    Evaluating fetal wellbeing during the intrapartum period to detect fetal compromise and hypoxia is a topic of considerable importance to midwives. In part this is because the events during this time can have profound significance for the physical and emotional wellbeing of all those involved, including the infant, mother and midwife. This article explores the ways midwives can detect fetal compromise, what they can do to limit the effects of cerebral hypoxic-ischaemia, and reviews neonatal treatments that,can optimise infant neurological outcome. PMID:27652437

  14. 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.

  15. 31 CFR 5.7 - When will Treasury entities compromise a Treasury debt?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... as described in Treasury Directive 34-02 (Credit Management and Debt Collection), which may be found... Treasury TREASURY DEBT COLLECTION Procedures To Collect Treasury Debts § 5.7 When will Treasury entities... Treasury entity may compromise the debt in accordance with the provisions of 31 CFR part 902 and...

  16. Adolescent Occupational Aspirations: Test of Gottfredson's Theory of Circumscription and Compromise

    ERIC Educational Resources Information Center

    Cochran, Daria B.; Wang, Eugene W.; Stevenson, Sarah J.; Johnson, Leah E.; Crews, Charles

    2011-01-01

    The authors investigated the relationship between adolescent occupational aspirations and midlife career success. The model for adolescent occupational aspirations was derived from Gottfredson's (1981) theory of circumscription and compromise. The authors hypothesized that parental socioeconomic status (SES), ability, and gender predict adolescent…

  17. 76 FR 15212 - Redelegation of Authority to Compromise and Close Civil Claims

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-21

    ... Attorney General all of the Assistant Attorney General's authority to compromise and close civil claims... Section, the Appellate Section, the Office of Review, and the Deputy Assistant Attorneys General, to... not exceed $250,000; provided that such redelegation is not made to the attorney-of-record in the...

  18. 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 NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM SBA Financial Assistance for NMVC Companies...

  19. 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…

  20. Congenital Vallecular Cyst Causing Airway Compromise in a 2-Month-Old Girl

    PubMed Central

    AlAbdulla, Amal Faisal

    2015-01-01

    Congenital vallecular cyst is a rare entity and may present with acute airway obstruction. This is a case of congenital vallecular cyst presenting with airway compromise requiring immediate management. The epidemiology, pathogenesis, and clinical presentation of vallecular cysts are discussed as well as the diagnosis and management. PMID:26240568

  1. 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...

  2. 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...

  3. 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…

  4. 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...

  5. 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...

  6. 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…

  7. 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 §...

  8. 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 §...

  9. A Preliminary Investigation of Three Compromise Methods for Establishing Cut-Off Scores.

    ERIC Educational Resources Information Center

    Mills, Craig N.; Melican, Gerald J.

    The study compares three methods for establishing cut-off scores that effect a compromise between absolute cut-offs based on item difficulty and relative cut-offs based on expected passing rates. Each method coordinates these two types of information differently. The Beuk method obtains judges' estimates of an absolute cut-off and an expected…

  10. 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...

  11. 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..., 2014. FOR FURTHER INFORMATION CONTACT: Concerning cost methodology, Eva Williams, at (202)...

  12. 44 CFR 295.7 - Authority to settle or compromise claims.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Authority to settle or compromise claims. 295.7 Section 295.7 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY CERRO GRANDE FIRE ASSISTANCE CERRO GRANDE FIRE ASSISTANCE...

  13. 44 CFR 295.7 - Authority to settle or compromise claims.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 44 Emergency Management and Assistance 1 2011-10-01 2011-10-01 false Authority to settle or compromise claims. 295.7 Section 295.7 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY CERRO GRANDE FIRE ASSISTANCE CERRO GRANDE FIRE ASSISTANCE...

  14. 45 CFR 608.2 - Collection, compromise, and use of consumer reporting agencies.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) NATIONAL SCIENCE FOUNDATION CLAIMS COLLECTION AND ADMINISTRATIVE OFFSET § 608.2 Collection, compromise, and... action of certain claims. In making demands for payment, NSF will follow the guidance set forth at 4 CFR 102.2. In appropriate cases, as authorized by and subject to 31 U.S.C. 3718 and 4 CFR 102.6, NSF...

  15. 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...

  16. 32 CFR 310.14 - Notification when information is lost, stolen, or compromised.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 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...

  17. 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...

  18. 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...

  19. 32 CFR 310.14 - Notification when information is lost, stolen, or compromised.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 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...

  20. 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...

  1. 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

  2. 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

  3. 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.

  4. 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.

  5. 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.

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

    PubMed

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

    2012-08-18

    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.

  7. 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.

  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. 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.

  10. 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.

  11. 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

  12. 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

  13. Mixing ability test compared with a comminution test in persons with normal and compromised masticatory performance.

    PubMed

    Speksnijder, C M; Abbink, J H; van der Glas, H W; Janssen, N G; van der Bilt, A

    2009-10-01

    A mastication test was needed with a material that forms a bolus and is soft enough to be chewed by persons with compromised oral function, in particular patients confronted with oral cancer. We therefore developed a wax-mixing ability test and compared it with a comminution test using Optocal as test food. We hypothesized that the mixing ability test would be better at differentiating between groups of persons with compromised masticatory performance than the comminution test. Sixty healthy subjects were recruited in three groups of 20, matched for age and gender: a group with natural dentition; a group with full dentures; and a group with maxillary denture and implant-supported mandibular overdenture. The mixing ability test was found to discriminate better between the two full-denture groups than the comminution test.

  14. 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

  15. Happenstance and compromise: a gendered analysis of students' computing degree course selection

    NASA Astrophysics Data System (ADS)

    Lang, Catherine

    2010-12-01

    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 choice. This investigation provides an insight into the contributing factors into the continued downturn of student diversity in computing bachelor degree courses. Many females interviewed made decisions based on happenstance, many males interviewed had chosen computing as a compromise course, and family helped in the decision-making to a large degree in both genders. The major implication from this investigation is the finding that students of both genders appear to be socialised away from this discipline, which is perceived as a support or insurance skill, not a career in itself, in all but the most technical-oriented (usually male) student.

  16. Mixing ability test compared with a comminution test in persons with normal and compromised masticatory performance.

    PubMed

    Speksnijder, C M; Abbink, J H; van der Glas, H W; Janssen, N G; van der Bilt, A

    2009-10-01

    A mastication test was needed with a material that forms a bolus and is soft enough to be chewed by persons with compromised oral function, in particular patients confronted with oral cancer. We therefore developed a wax-mixing ability test and compared it with a comminution test using Optocal as test food. We hypothesized that the mixing ability test would be better at differentiating between groups of persons with compromised masticatory performance than the comminution test. Sixty healthy subjects were recruited in three groups of 20, matched for age and gender: a group with natural dentition; a group with full dentures; and a group with maxillary denture and implant-supported mandibular overdenture. The mixing ability test was found to discriminate better between the two full-denture groups than the comminution test. PMID:19758256

  17. 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

  18. 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

  19. 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

  20. 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

  1. 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

  2. The administration of probiotics and synbiotics in immune compromised adults: is it safe?

    PubMed

    Van den Nieuwboer, M; Brummer, R J; Guarner, F; Morelli, L; Cabana, M; Claasen, E

    2015-03-01

    This study aimed to systematically evaluate safety of probiotics and synbiotics in immune compromised adults (≥18 years). Safety was analysed using the Common Terminology Clinical Adverse Events (CTCAE version 4.0) classification, thereby providing an update on previous reports using the most recent available clinical data (2008-2013). Safety aspects are represented and related to number of participants per probiotic strain/culture, study duration, dosage, clinical condition and selected afflictions. Analysis of 57 clinical studies indicates that probiotic and/or synbiotic administration in immune compromised adults is safe with regard to the current evaluated probiotic strains, dosages and duration. Individuals were considered immune compromised if HIV-infected, critically ill, underwent surgery or had an organ- or an autoimmune disease. There were no major safety concerns in the study, as none of the serious adverse events (AE)s were related, or suspected to be related, to the probiotic or synbiotic product and the study products were well tolerated. Overall, AEs occurred less frequent in immune compromised subjects receiving probiotics and/or synbiotics compared to the control group. In addition, the results demonstrated a flaw in precise reporting and classification of AE in most studies. Furthermore, generalisability of conclusions are greatly limited by the inconsistent, imprecise and potentially incomplete reporting as well as the variation in probiotic strains, dosages, administration regimes, study populations and reported outcomes. We argue that standardised reporting on adverse events (CTCAE) in 'food' studies should be obligatory, thereby improving reliability of data and re-enforcing the safety profile of probiotics.

  3. 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

    ... expenses is computed as follows: (i) Determine the ratio of the amount awarded (less the reasonable and...) Determining amount of compromise settlement considered as a payment for medical expenses. (1) If a compromise settlement allocates a portion of the payment for medical expenses and also gives reasonable recognition...

  4. 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

    ... valorem penalties. Neither the taxpayer nor the Government shall, upon acceptance of an offer in.... However, acceptance of an offer in compromise of a civil liability does not remit a criminal liability, nor does acceptance of an offer in compromise of a criminal liability remit a civil liability....

  5. 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

  6. 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

  7. 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

  8. 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.

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. Identifying compromised systems through correlation of suspicious traffic from malware behavioral analysis

    NASA Astrophysics Data System (ADS)

    Camilo, Ana E. F.; Grégio, André; Santos, Rafael D. C.

    2016-05-01

    Malware detection may be accomplished through the analysis of their infection behavior. To do so, dynamic analysis systems run malware samples and extract their operating system activities and network traffic. This traffic may represent malware accessing external systems, either to steal sensitive data from victims or to fetch other malicious artifacts (configuration files, additional modules, commands). In this work, we propose the use of visualization as a tool to identify compromised systems based on correlating malware communications in the form of graphs and finding isomorphisms between them. We produced graphs from over 6 thousand distinct network traffic files captured during malware execution and analyzed the existing relationships among malware samples and IP addresses.

  14. Demographic corrections appear to compromise classification accuracy for severely skewed cognitive tests.

    PubMed

    O'Connell, Megan E; Tuokko, Holly; Kadlec, Helena

    2011-04-01

    Demographic corrections for cognitive tests should improve classification accuracy by reducing age or education biases, but empirical support has been equivocal. Using a simulation procedure, we show that creating moderate or extreme skewness in cognitive tests compromises the classification accuracy of demographic corrections, findings that appear replicated within clinical data for the few neuropsychological test scores with an extreme degree of skew. For most neuropsychological tests, the dementia classification accuracy of raw and demographically corrected scores was equivalent. These findings suggest that the dementia classification accuracy of demographic corrections is robust to slight degrees of skew (i.e., skewness <1.5). PMID:21154077

  15. Pathogen Associated Molecular Pattern (PAMP)-Triggered Immunity Is Compromised under C-Limited Growth

    PubMed Central

    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

    2015-01-01

    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

  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. 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.

  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. Focal cartilage defect compromises fluid-pressure dependent load support in the knee joint.

    PubMed

    Dabiri, Yaghoub; Li, LePing

    2015-06-01

    A focal cartilage defect involves tissue loss or rupture. Altered mechanics in the affected joint may play an essential role in the onset and progression of osteoarthritis. The objective of the present study was to determine the compromised load support in the human knee joint during defect progression from the cartilage surface to the cartilage-bone interface. Ten normal and defect cases were simulated with a previously tested 3D finite element model of the knee. The focal defects were considered in both condyles within high load-bearing regions. Fluid pressurization, anisotropic fibril-reinforcement, and depth-dependent mechanical properties were considered for the articular cartilages and menisci. The results showed that a small cartilage defect could cause 25% reduction in the load support of the knee joint due to a reduced capacity of fluid pressurization in the defect cartilage. A partial-thickness defect could cause a fluid pressure decrease or increase in the remaining underlying cartilage depending on the defect depth. A cartilage defect also increased the shear strain at the cartilage-bone interface, which was more significant with a full-thickness defect. The effect of cartilage defect on the fluid pressurization also depended on the defect sites and contact conditions. In conclusion, a focal cartilage defect causes a fluid-pressure dependent load reallocation and a compromised load support in the joint, which depend on the defect depth, site, and contact condition.

  20. Compromised Structure and Function of HDAC8 Mutants Identified in Cornelia de Lange Syndrome Spectrum Disorders

    PubMed Central

    2015-01-01

    Cornelia de Lange Syndrome (CdLS) is a multiple congenital anomaly disorder resulting from mutations in genes that encode the core components of the cohesin complex, SMC1A, SMC3, and RAD21, or two of its regulatory proteins, NIPBL and HDAC8. HDAC8 is the human SMC3 lysine deacetylase required for cohesin recycling in the cell cycle. To date, 16 different missense mutations in HDAC8 have recently been identified in children diagnosed with CdLS. To understand the molecular effects of these mutations in causing CdLS and overlapping phenotypes, we have fully characterized the structure and function of five HDAC8 mutants: C153F, A188T, I243N, T311M, and H334R. X-ray crystal structures reveal that each mutation causes local structural changes that compromise catalysis and/or thermostability. For example, the C153F mutation triggers conformational changes that block acetate product release channels, resulting in only 2% residual catalytic activity. In contrast, the H334R mutation causes structural changes in a polypeptide loop distant from the active site and results in 91% residual activity, but the thermostability of this mutant is significantly compromised. Strikingly, the catalytic activity of these mutants can be partially or fully rescued in vitro by the HDAC8 activator N-(phenylcarbamothioyl)benzamide. These results suggest that HDAC8 activators might be useful leads in the search for new therapeutic strategies in managing CdLS. PMID:25075551

  1. Indications and contraindications of dental implants in medically compromised patients: update.

    PubMed

    Gómez-de Diego, Rafael; Mang-de la Rosa, María del Rocío; Romero-Pérez, María-Jesús; Cutando-Soriano, Antonio; López-Valverde-Centeno, Antonio

    2014-09-01

    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.

  2. 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.

  3. 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

  4. 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.

  5. 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

  6. 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.

  7. 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

  8. Focal cartilage defect compromises fluid-pressure dependent load support in the knee joint.

    PubMed

    Dabiri, Yaghoub; Li, LePing

    2015-06-01

    A focal cartilage defect involves tissue loss or rupture. Altered mechanics in the affected joint may play an essential role in the onset and progression of osteoarthritis. The objective of the present study was to determine the compromised load support in the human knee joint during defect progression from the cartilage surface to the cartilage-bone interface. Ten normal and defect cases were simulated with a previously tested 3D finite element model of the knee. The focal defects were considered in both condyles within high load-bearing regions. Fluid pressurization, anisotropic fibril-reinforcement, and depth-dependent mechanical properties were considered for the articular cartilages and menisci. The results showed that a small cartilage defect could cause 25% reduction in the load support of the knee joint due to a reduced capacity of fluid pressurization in the defect cartilage. A partial-thickness defect could cause a fluid pressure decrease or increase in the remaining underlying cartilage depending on the defect depth. A cartilage defect also increased the shear strain at the cartilage-bone interface, which was more significant with a full-thickness defect. The effect of cartilage defect on the fluid pressurization also depended on the defect sites and contact conditions. In conclusion, a focal cartilage defect causes a fluid-pressure dependent load reallocation and a compromised load support in the joint, which depend on the defect depth, site, and contact condition. PMID:25727068

  9. 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.

  10. Mixed-species biofilm compromises wound healing by disrupting epidermal barrier function.

    PubMed

    Roy, Sashwati; Elgharably, Haytham; 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

    2014-08-01

    In chronic wounds, biofilm infects host tissue for extended periods of time. This work establishes the first chronic preclinical model of wound biofilm infection aimed at addressing the 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 postclosure. Study of the 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 (TEWL). Intervention strategies aimed at inhibiting biofilm-inducible miRNAs may be productive in restoring the barrier function of host skin.

  11. 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

  12. Constraining the brachial plexus does not compromise regional control in oropharyngeal carcinoma

    PubMed Central

    2013-01-01

    Background Accumulating evidence suggests that brachial plexopathy following head and neck cancer radiotherapy may be underreported and that this toxicity is associated with a dose–response. Our purpose was to determine whether the dose to the brachial plexus (BP) can be constrained, without compromising regional control. Methods The radiation plans of 324 patients with oropharyngeal carcinoma (OPC) treated with intensity-modulated radiation therapy (IMRT) were reviewed. We identified 42 patients (13%) with gross nodal disease <1 cm from the BP. Normal tissue constraints included a maximum dose of 66 Gy and a D05 of 60 Gy for the BP. These criteria took precedence over planning target volume (PTV) coverage of nodal disease near the BP. Results There was only one regional failure in the vicinity of the BP, salvaged with neck dissection (ND) and regional re-irradiation. There have been no reported episodes of brachial plexopathy to date. Conclusions In combined-modality therapy, including ND as salvage, regional control did not appear to be compromised by constraining the dose to the BP. This approach may improve the therapeutic ratio by reducing the long-term risk of brachial plexopathy. PMID:23835205

  13. Effect of reinforcement with resin composite on fracture strength of structurally compromised roots.

    PubMed

    Fukui, Yuji; Komada, Wataru; Yoshida, Keiichi; Otake, Shiho; Okada, Daizo; Miura, Hiroyuki

    2009-09-01

    This study was aimed at evaluating the fracture resistance of structurally compromised roots restored with four different post and core systems. Thirty-two bovine roots were uniformly shaped to simulate human mandibular premolar roots. The roots were divided into four groups based on the type of restoration: cemented cast post and core (Group MC), resin composite build-up (Group CR), resin composite and prefabricated glass fiber post build-up (Group FRC), and thick-layer dual-cured resin composite-reinforced small-diameter tapered cast post and core (Group CRM). After a static loading test, the failure mode and fracture resistance were recorded. Group CRM (719.38+/-196.73 N) exhibited a significantly high fracture resistance compared with the other groups (Group MC: 429.56+/-82.43 N; Group CR: 349.56+/-66.21 N; Group FRC: 398.94+/-112.71 N; p<0.05). In conclusion, Group CRM exhibited better mechanical properties for structurally compromised roots with no ferrules, although all types of restorations showed non-restorable fracture modes. PMID:19822992

  14. Can Neglected Tropical Diseases Compromise Human Wellbeing in Sex-, Age-, and Trait-Specific Ways?

    PubMed

    Geary, David C

    2016-04-01

    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

  15. Bioavailable transition metals in particulate matter mediate cardiopulmonary injury in healthy and compromised animal models.

    PubMed Central

    Costa, D L; Dreher, K L

    1997-01-01

    Many epidemiologic reports associate ambient levels of particulate matter (PM) with human mortality and morbidity, particularly in people with preexisting cardiopulmonary disease (e.g., chronic obstructive pulmonary disease, infection, asthma). Because much ambient PM is derived from combustion sources, we tested the hypothesis that the health effects of PM arise from anthropogenic PM that contains bioavailable transition metals. The PM samples studied derived from three emission sources (two oil and one coal fly ash) and four ambient airsheds (St. Louis, MO; Washington; Dusseldorf, Germany; and Ottawa, Canada). PM was administered to rats by intratracheal instillation in equimass or equimetal doses to address directly the influence of PM mass versus metal content on acute lung injury and inflammation. Our results indicated that the lung dose of bioavailable transition metal, not instilled PM mass, was the primary determinant of the acute inflammatory response for both the combustion source and ambient PM samples. Residual oil fly ash, a combustion PM rich in bioavailable metal, was evaluated in a rat model of cardiopulmonary disease (pulmonary vasculitis/hypertension) to ascertain whether the disease state augmented sensitivity to that PM. Significant mortality and enhanced airway responsiveness were observed. Analysis of the lavaged lung fluids suggested that the milieu of the inflamed lung amplified metal-mediated oxidant chemistry to jeopardize the compromised cardiopulmonary system. We propose that soluble metals from PM mediate the array of PM-associated injuries to the cardiopulmonary system of the healthy and at-risk compromised host. PMID:9400700

  16. 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

  17. 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...

  18. 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...

  19. 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...

  20. 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.

  1. 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.

  2. 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

  3. 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

  4. 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.

  5. 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.

  6. Non-Surgical Management of Critically Compromised Airway Due to Dilatation of Interposed Colon.

    PubMed

    Min, Jinsoo; Cho, Young-Jae

    2016-04-01

    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

  7. 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.

  8. Conflicts of interest in research: is clinical decision-making compromised? An opinion paper.

    PubMed

    Adibi, Shawn; Abidi, Shawn; Bebermeyer, Richard D

    2010-08-01

    Lack of transparency in funded research can compromise clinical decision-making in an evidence-based practice. Transparency can be defined as full disclosure of all financial assistance and support to authors and investigators. There is a perception that ethical principles are eroding and that research data can be biased due to conflicts of interest. These research outcomes biased or not, are used for clinical decision-making in the evidence-based practice. One suggested solution to this common ethical dilemma is to continue the dialogue on transparency in research and to create oversight bodies which include representatives from business and industry, private practice, academia, and research. There is increasing evidence of the need for more ethics education at all levels.

  9. Audiologic Management of Older Adults With Hearing Loss and Compromised Cognitive/Psychoacoustic Auditory Processing Capabilities

    PubMed Central

    Kricos, Patricia B.

    2006-01-01

    The number and proportion of older adults in the United States population is increasing, and more clinical audiologists will be called upon to deliver hearing care to the approximately 35% to 50% of them who experience hearing difficulties. In recent years, the characteristics and sources of receptive communication difficulties in older individuals have been investigated by hearing scientists, cognitive psychologists, and audiologists. It is becoming increasingly apparent that cognitive compromises and psychoacoustic auditory processing disorders associated with aging may contribute to communication difficulties in this population. This paper presents an overview of best practices, based on our current knowledge base, for clinical management of older individuals with limitations in cognitive or psychoacoustic auditory processing capabilities, or both, that accompany aging. PMID:16528428

  10. 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

  11. 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

  12. 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.

  13. Rural and urban older African caregivers coping with HIV/AIDS are nutritionally compromised.

    PubMed

    Kruger, Annamarie; Lekalakalamokgela, Sebi E; Wentzel-Viljoen, Edelweiss

    2011-01-01

    This article describes the nutritional status of a group of rural and urban free living African older surrogate parents caring for HIV/AIDS orphans and grandchildren. Multiple sources of data collection were used, including anthropometry, biochemical analyses, and quantitative questionnaires. The diets of these older participants were marginal. The rural to urban geographical transition in these older persons is characterized by a better micronutrient and trace element intake; however, urban dwellers also had higher fat intakes, increasing the risk for cardiovascular disease. These results suggest that to be a surrogate grandparent provides a special meaning to the life of men that needs to be better understood. However, the diets of these older people caring for HIV/AIDS-affected children were more compromised than those of non-caregivers. PMID:21846243

  14. Artemisinin mimics calorie restriction to trigger mitochondrial biogenesis and compromise telomere shortening in mice.

    PubMed

    Wang, Da-Ting; He, Jiang; Wu, Ming; Li, Si-Ming; Gao, Qian; Zeng, Qing-Ping

    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.

  15. 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

  16. Rare Presentation of Gall Bladder Tuberculosis in a Non Immuno-Compromised Patient.

    PubMed

    Kumar, Pawan; Hazrah, Priya; Taneja, Anil; Ahuja, Arvind; Sharma, Deborshi

    2015-04-24

    The gall bladder is least common intra-abdominal organ to be involved by tuberculosis. It is either part of systemic miliary tuberculosis or abdominal tuberculosis. Isolated gall bladder tuberculosis is even rarer, can presents either as calculus or acalculus cholecystitis. Gall bladder tuberculosis presenting as a localized perforation with a sinus formation into anterior abdominal wall is unreported complication in a non immuno-compromised person. A 48-year old female presented with a gradually increasing swelling in right hypochondrium. Abdominal ultrasound showed superficial collection over right hypochondrium with intraperitoneal extension. Computed tomography showed localized gall bladder perforation with extension to the abdominal wall. Patient underwent emergency exploration and cholecystectomy with excision of sinus tract and drainage of abdominal wall abscess. Histopathological examination showed granulomatous cholecystitis suggestive of tuberculosis of gall bladder with extension into the sinus tract. She had an uneventful recovery and was treated with 6-month antitubercular therapy after surgery. PMID:26236458

  17. Perioperative Respiratory Compromise in Patients Undergoing PCNL-A Case Series.

    PubMed

    Namasivayam S, Ponnambala; Gayathri; Indu

    2013-10-01

    Percutaneous Nephrolithotomy (PCNL) is a surgical procedure which is used to extract renal pelvic stones. An optimum access tract, without traumatizing the surrounding structures, is essential for the surgery. Trauma to the surrounding structures and extra-vasation of the irrigating fluid may result in complications like hydrothorax, pneumothorax, hydro pneumothorax etc. These complications may produce intra- operative respiratory compromise leading on to arterial hypoxemia and its sequelae. A series of three case reports with review is presented here. First case is accumulation of irrigating fluid in the pleura causing hydrothorax and oxygen desaturation. Second case is extra-vasation of fluid in the abdominal wall and the patient was ventilated artificially for 24 hours. Third patient developed pneumothorax and he needed chest drainage.PCNL is done under general anaesthesia in prone position. The anaesthesiologist should be vigil enough to identify the situation and take appropriate measures to correct it.

  18. Perioperative Respiratory Compromise in Patients Undergoing PCNL-A Case Series

    PubMed Central

    Namasivayam S., Ponnambala; Gayathri; Indu

    2013-01-01

    Percutaneous Nephrolithotomy (PCNL) is a surgical procedure which is used to extract renal pelvic stones. An optimum access tract, without traumatizing the surrounding structures, is essential for the surgery. Trauma to the surrounding structures and extra–vasation of the irrigating fluid may result in complications like hydrothorax, pneumothorax, hydro pneumothorax etc. These complications may produce intra– operative respiratory compromise leading on to arterial hypoxemia and its sequelae. A series of three case reports with review is presented here. First case is accumulation of irrigating fluid in the pleura causing hydrothorax and oxygen desaturation. Second case is extra–vasation of fluid in the abdominal wall and the patient was ventilated artificially for 24 hours. Third patient developed pneumothorax and he needed chest drainage.PCNL is done under general anaesthesia in prone position. The anaesthesiologist should be vigil enough to identify the situation and take appropriate measures to correct it. PMID:24298514

  19. A further elaboration of needs in psychoanalysis: needs in conflict, compromise, and harmony.

    PubMed

    Sollars, Franklin R

    2013-04-01

    The author begins by providing a brief history of the use of the concept of needs in psychoanalysis. Suggesting that a more phenomenological/contextual perspective of motivation would be useful, he conceptualizes a healthy versus unhealthy dichotomization of needs as at least partially fitting this bill, and then develops a platform to view needs from an intrapsychic conflict perspective historically reserved for instinctual conflict theory. Moving away from a biological reductionistic view of needs, he describes a needs health by its relationship to love or, conversely, needs unhealthiness by its relationship to egotism, vanity, and being against others and one's real self. Providing clinical and case examples, the dynamic interplay of needs in conflict, compromise, and harmony in the human personality is elaborated.

  20. 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.

  1. A deletion in the bovine FANCI gene compromises fertility by causing fetal death and brachyspina.

    PubMed

    Charlier, Carole; Agerholm, Jorgen Steen; Coppieters, Wouter; Karlskov-Mortensen, Peter; Li, Wanbo; de Jong, Gerben; Fasquelle, Corinne; Karim, Latifa; Cirera, Susanna; Cambisano, Nadine; Ahariz, Naima; Mullaart, Erik; Georges, Michel; Fredholm, Merete

    2012-01-01

    Fertility is one of the most important traits in dairy cattle, and has been steadily declining over the last decades. We herein use state-of-the-art genomic tools, including high-throughput SNP genotyping and next-generation sequencing, to identify a 3.3 Kb deletion in the FANCI gene causing the brachyspina syndrome (BS), a rare recessive genetic defect in Holstein dairy cattle. We determine that despite the very low incidence of BS (<1/100,000), carrier frequency is as high as 7.4% in the Holstein breed. We demonstrate that this apparent discrepancy is likely due to the fact that a large proportion of homozygous mutant calves die during pregnancy. We postulate that several other embryonic lethals may segregate in livestock and significantly compromise fertility, and propose a genotype-driven screening strategy to detect the corresponding deleterious mutations. PMID:22952632

  2. Using Deterministic, Gated Item Response Theory Model to detect test cheating due to item compromise.

    PubMed

    Shu, Zhan; Henson, Robert; Luecht, Richard

    2013-07-01

    The Deterministic, Gated Item Response Theory Model (DGM, Shu, Unpublished Dissertation. The University of North Carolina at Greensboro, 2010) is proposed to identify cheaters who obtain significant score gain on tests due to item exposure/compromise by conditioning on the item status (exposed or unexposed items). A "gated" function is introduced to decompose the observed examinees' performance into two distributions (the true ability distribution determined by examinees' true ability and the cheating distribution determined by examinees' cheating ability). Test cheaters who have score gain due to item exposure are identified through the comparison of the two distributions. Hierarchical Markov Chain Monte Carlo is used as the model's estimation framework. Finally, the model is applied in a real data set to illustrate how the model can be used to identify examinees having pre-knowledge on the exposed items.

  3. Rehabilitation of periodontally compromised teeth with fiber-reinforced composite resin: a case report.

    PubMed

    Hoeppner, Márcio Grama; Fonseca, Rodrigo Borges; Pfau, Eduardo Augusto; Justo, Flávio Roberto Machado; Fávero, Alexandre; Bremm, Laerte Luiz

    2011-02-01

    The rehabilitation of prosthetic spaces resulting from severe periodontitis represents a challenge in terms of functional and esthetic aspects. Generally, tooth extraction is followed by alveolar ridge volume reduction, which increases the esthetic problem. The aim of this article is to report the integration of esthetics and functional parameters in the oral rehabilitation of extracted periodontally compromised mandibular central incisors through the construction of a direct glass fiber-reinforced composite fixed partial denture (DFPD). After periodontal therapy, the patient received a periodontal subepithelial graft, enabling an increase in the thickness and height of the alveolar ridge. The DFPD was fabricated with the use of extracted teeth. Mandibular canines and lateral incisors received cavities 2 mm deep and wide. After fiber insertion, tooth adaptation, and composite resin coverage, the teeth were finished and polished. Results showed an excellent esthetic result with stabilization and function of the remaining periodontally affected teeth. PMID:21359245

  4. 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

  5. Processing of visual information compromises the ability of older adults to control novel fine motor tasks.

    PubMed

    Baweja, Harsimran S; Kwon, MinHyuk; Onushko, Tanya; Wright, David L; Corcos, Daniel M; Christou, Evangelos A

    2015-12-01

    We performed two experiments to determine whether amplified motor output variability and compromised processing of visual information in older adults impair short-term adaptations when learning novel fine motor tasks. In Experiment 1, 12 young and 12 older adults underwent training to learn how to accurately trace a sinusoidal position target with abduction-adduction of their index finger. They performed 48 trials, which included 8 blocks of 6 trials (the last trial of each block was performed without visual feedback). Afterward, subjects received an interference task (watched a movie) for 60 min. We tested retention by asking subjects to perform the sinusoidal task (5 trials) with and without visual feedback. In Experiment 2, 12 young and 10 older adults traced the same sinusoidal position target with their index finger and ankle at three distinct visual angles (0.25°, 1° and 5.4°). In Experiment 1, the movement error and variability were greater for older adults during the visual feedback trials when compared with young adults. In contrast, during the no-vision trials, age-associated differences in movement error and variability were ameliorated. Short-term adaptations in learning the sinusoidal task were similar for young and older adults. In Experiment 2, lower amount of visual feedback minimized the age-associated differences in movement variability for both the index finger and ankle movements. We demonstrate that although short-term adaptations are similar for young and older adults, older adults do not process visual information as well as young adults and that compromises their ability to control novel fine motor tasks during acquisition, which could influence long-term retention and transfer.

  6. 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

  7. 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

  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. Paclitaxel-Releasing Thin Biodegradable Film for Prevention of Bleb Avascularity Without Compromising Filtration in Rabbits

    PubMed Central

    Okuda, Tetsuhiko; Higashide, Tomomi; Sakurai, Mayumi; Fukuhira, Yukako; Kaneko, Hiroaki; Shimomura, Masatsugu; Sugiyama, Kazuhisa

    2015-01-01

    Purpose: A honeycomb-patterned film (HPF) prevents bleb scarring and mitomycin C (MMC)-related bleb avascularity in a rabbit model of filtration surgery. In this study, we examined whether a HPF-releasing paclitaxel (PTX) can prevent bleb avascularity without compromising filtration. Methods: Filtration surgery was performed in one eye of rabbits. A 14-μm thick HPF made from poly(L-lactide-co-ε-caprolactone) was placed subconjunctivally over the filtration site with the honeycomb surface turned toward the subconjunctival Tenon tissue. The rabbits were divided into four groups (n = 5 each): 1, HPF with no drug; 2, HPF + PTX 50 μg; 3, HPF + 5 μg; 4, HPF + 0.5 μg. Intraocular pressure (IOP) measurements and bleb evaluations using ultrasound biomicroscopy were performed periodically for 4 weeks followed by histological examination. A longer follow-up study (12 weeks) was performed for group 4 (experiment 2; n = 8). Results: Among all groups at the 4-week follow up, two blebs failed in group 1. The postoperative IOP decrease was significantly greater in PTX-treated eyes than in group 1. The bleb avascular area persisted for 4 weeks in groups 2 and 3. However, no avascular area was observed in groups 1 and 4 at 4 weeks postoperatively. Histology showed minimal fibrosis at the filtration site in all the PTX groups. In experiment 2, some blebs became flatter starting at 10 weeks after surgery. Conclusions: PTX released from HPF promoted bleb survival and IOP decrease. The lowest dose of PTX (0.5 μg) was effective at preventing bleb avascularity without compromising filtration. PMID:26101723

  10. Staurosporine Induces Necroptotic Cell Death under Caspase-Compromised Conditions in U937 Cells

    PubMed Central

    Dunai, Zsuzsanna A.; Imre, Gergely; Barna, Gabor; Korcsmaros, Tamas; Petak, Istvan; Bauer, Pal I.; Mihalik, Rudolf

    2012-01-01

    For a long time necrosis was thought to be an uncontrolled process but evidences recently have revealed that necrosis can also occur in a regulated manner. Necroptosis, a type of programmed necrosis is defined as a death receptor-initiated process under caspase-compromised conditions. The process requires the kinase activity of receptor-interacting protein kinase 1 and 3 (RIPK1 and RIPK3) and mixed lineage kinase domain-like protein (MLKL), as a substrate of RIPK3. The further downstream events remain elusive. We applied known inhibitors to characterize the contributing enzymes in necroptosis and their effect on cell viability and different cellular functions were detected mainly by flow cytometry. Here we report that staurosporine, the classical inducer of intrinsic apoptotic pathway can induce necroptosis under caspase-compromised conditions in U937 cell line. This process could be hampered at least partially by the RIPK1 inhibitor necrotstin-1 and by the heat shock protein 90 kDa inhibitor geldanamycin. Moreover both the staurosporine-triggered and the classical death ligand-induced necroptotic pathway can be effectively arrested by a lysosomal enzyme inhibitor CA-074-OMe and the recently discovered MLKL inhibitor necrosulfonamide. We also confirmed that the enzymatic role of poly(ADP-ribose)polymerase (PARP) is dispensable in necroptosis but it contributes to membrane disruption in secondary necrosis. In conclusion, we identified a novel way of necroptosis induction that can facilitate our understanding of the molecular mechanisms of necroptosis. Our results shed light on alternative application of staurosporine, as a possible anticancer therapeutic agent. Furthermore, we showed that the CA-074-OMe has a target in the signaling pathway leading to necroptosis. Finally, we could differentiate necroptotic and secondary necrotic processes based on participation of PARP enzyme. PMID:22860037

  11. 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.

  12. 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

  13. A case report of reattachment of fractured root fragment and resin-composite reinforcement in a compromised endodontically treated root.

    PubMed

    Lui, J L

    2001-10-01

    The composite reinforcement technique has been used clinically to salvage damaged root-filled teeth compromised by caries, trauma, developmental abnormalities, internal resorption and iatrogenic causes. This clinical case report describes the use of the technique to reattach a fractured fragment in a compromised endodontically treated root besides reinforcing it for continued function in the mouth. Factors of clinical importance related to this additional application; including reattachment of tooth fragments, post crown retention, coronal microleakage and fracture resistance and strength, are also briefly discussed.

  14. A case report of reattachment of fractured root fragment and resin-composite reinforcement in a compromised endodontically treated root.

    PubMed

    Lui, J L

    2001-10-01

    The composite reinforcement technique has been used clinically to salvage damaged root-filled teeth compromised by caries, trauma, developmental abnormalities, internal resorption and iatrogenic causes. This clinical case report describes the use of the technique to reattach a fractured fragment in a compromised endodontically treated root besides reinforcing it for continued function in the mouth. Factors of clinical importance related to this additional application; including reattachment of tooth fragments, post crown retention, coronal microleakage and fracture resistance and strength, are also briefly discussed. PMID:11678543

  15. 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

  16. 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.

  17. 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

  18. 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

  19. 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.

  20. 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.

  1. 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

  2. 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

  3. Siphon regeneration capacity is compromised during aging in the ascidian Ciona intestinalis.

    PubMed

    Jeffery, William R

    2012-01-01

    The ascidian Ciona intestinalis has a short life span and powerful regeneration capacities. The regeneration of the oral siphon (OS) involves wound healing, blastema formation, cell proliferation, and replacement of 8 oral pigment organs (OPO), the latter via differentiation and migration of stem/precursor cells from localized niches in the siphon. The restoration of OPO pattern during OS regeneration occurs with a high degree of accuracy through three successive cycles of amputation. It is shown here that oral siphons of the largest and oldest members of a wild Ciona population do not completely regenerate their siphons after amputation. The loss of regeneration capacity was accompanied by reduced cell proliferation. In contrast to arrested OS outgrowth, the stem/precursor cells responsible for OPO replacement "over-differentiate" after OS amputation in the oldest animals, the typical number of OPO is increased from 8 to 12-16, and malformed OPO are produced. Also in contrast to younger animals, the oldest animals of the population show arrested OPO development after two consecutive cycles of amputation and regeneration. We conclude that there is a size and age threshold in Ciona after which the regenerative capacity of the OS is compromised due to effects of aging on cell proliferation.

  4. mTOR Overactivation and Compromised Autophagy in the Pathogenesis of Pulmonary Fibrosis

    PubMed Central

    Gui, Yao-Song; Wang, Lianmei; Tian, Xinlun; Li, Xue; Ma, Aiping; Zhou, Weixun; Zeng, Ni; Zhang, Ji; Cai, Baiqiang; Zhang, Hongbing; Chen, Jing-Yu; Xu, Kai-Feng

    2015-01-01

    The mammalian target of rapamycin (mTOR) signaling pathway in pulmonary fibrosis was investigated in cell and animal models. mTOR overactivation in alveolar epithelial cells (AECs) was achieved in the conditional and inducible Tsc1 knock-down mice SPC-rtTA/TetO-Cre/Tsc1fx/+ (STT). Doxycycline caused Tsc1 knock-down and consequently mTOR activation in AECs for the STT mice. Mice treated with bleomycin exhibited increased mortality and pulmonary fibrosis compared with control mice. In wild-type C57BL/6J mice, pretreatment with rapamycin attenuated the bleomycin-mediated mortality and fibrosis. Rapamycin-mediated mouse survival benefit was inhibited by chloroquine, an autophagy inhibitor. Autophagosomes were decreased in the lungs after bleomycin exposure. Rapamycin induced the production of autophagosomes and diminished p62. We concluded that mTOR overactivation in AECs and compromised autophagy in the lungs are involved in the pathogenesis of pulmonary fibrosis. The suppression of mTOR and enhancement of autophagy may be used for treatment of pulmonary fibrosis. PMID:26382847

  5. Protozoan predation in soil slurries compromises determination of contaminant mineralization potential.

    PubMed

    Badawi, Nora; Johnsen, Anders R; Brandt, Kristian K; Sørensen, Jan; Aamand, Jens

    2012-11-01

    Soil suspensions (slurries) are commonly used to estimate the potential of soil microbial communities to mineralize organic contaminants. The preparation of soil slurries disrupts soil structure, however, potentially affecting both the bacterial populations and their protozoan predators. We studied the importance of this "slurry effect" on mineralization of the herbicide 2-methyl-4-chlorophenoxyacetic acid (MCPA, (14)C-labelled), focussing on the effects of protozoan predation. Mineralization of MCPA was studied in "intact" soil and soil slurries differing in soil:water ratio, both in the presence and absence of the protozoan activity inhibitor cycloheximide. Protozoan predation inhibited mineralization in dense slurry of subsoil (soil:water ratio 1:3), but only in the most dilute slurry of topsoil (soil:water ratio 1:100). Our results demonstrate that protozoan predation in soil slurries may compromise quantification of contaminant mineralization potential, especially when the initial density of degrader bacteria is low and their growth is controlled by predation during the incubation period.

  6. 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

  7. 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

  8. Skeletal muscle capillary density and microvascular function are compromised with aging and type 2 diabetes.

    PubMed

    Groen, Bart B L; Hamer, Henrike M; Snijders, Tim; van Kranenburg, Janneau; Frijns, Dionne; Vink, Hans; van Loon, Luc J C

    2014-04-15

    Adequate muscle perfusion is required for the maintenance of skeletal muscle mass. Impairments in microvascular structure and/or function with aging and type 2 diabetes have been associated with the progressive loss of skeletal muscle mass. Our objective was to compare muscle fiber type specific capillary density and endothelial function between healthy young men, healthy older men, and age-matched type 2 diabetes patients. Fifteen healthy young men (24 ± 1 yr), 15 healthy older men (70 ± 2 yr), and 15 age-matched type 2 diabetes patients (70 ± 1 yr) were selected to participate in the present study. Whole body insulin sensitivity, muscle fiber type specific capillary density, sublingual microvascular density, and dimension of the erythrocyte-perfused boundary region were assessed to evaluate the impact of aging and/or type 2 diabetes on microvascular structure and function. Whole body insulin sensitivity was significantly lower at a more advanced age, with lowest values reported in the type 2 diabetic patients. In line, skeletal muscle capillary contacts were much lower in the older and older type 2 diabetic patients when compared with the young. Sidestream darkfield imaging showed a significantly greater thickness of the erythrocyte perfused boundary region in the type 2 diabetic patients compared with the young. Skeletal muscle capillary density is reduced with aging and type 2 diabetes and accompanied by impairments in endothelial glycocalyx function, which is indicative of compromised vascular function. PMID:24577061

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. 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

  14. 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

  15. '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

  16. 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

  17. Generation of DNA single-strand displacement by compromised nucleotide excision repair

    PubMed Central

    Godon, Camille; Mourgues, Sophie; Nonnekens, Julie; Mourcet, Amandine; Coin, Fréderic; Vermeulen, Wim; Mari, Pierre-Olivier; Giglia-Mari, Giuseppina

    2012-01-01

    Nucleotide excision repair (NER) is a precisely coordinated process essential to avoid DNA damage-induced cellular malfunction and mutagenesis. Here, we investigate the mechanistic details and effects of the NER machinery when it is compromised by a pathologically significant mutation in a subunit of the repair/transcription factor TFIIH, namely XPD. In contrast to previous studies, we find that no single- or double-strand DNA breaks are produced at early time points after UV irradiation of cells bearing a specific XPD mutation, despite the presence of a clear histone H2AX phosphorylation (γH2AX) signal in the UV-exposed areas. We show that the observed γH2AX signal can be explained by the presence of longer single-strand gaps possibly generated by strand displacement. Our in vivo measurements also indicate a strongly reduced TFIIH-XPG binding that could promote single-strand displacement at the site of UV lesions. This finding not only highlights the crucial role of XPG's interactions with TFIIH for proper NER, but also sheds new light on how a faulty DNA repair process can induce extreme genomic instability in human patients. PMID:22863773

  18. 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.

  19. 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

  20. 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

  1. 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

  2. Increased Dynamic Effects in a Catalytically Compromised Variant of Escherichia coli Dihydrofolate Reductase

    PubMed Central

    2013-01-01

    Isotopic substitution (15N, 13C, 2H) of a catalytically compromised variant of Escherichia coli dihydrofolate reductase, EcDHFR-N23PP/S148A, has been used to investigate the effect of these mutations on catalysis. The reduction of the rate constant of the chemical step in the EcDHFR-N23PP/S148A catalyzed reaction is essentially a consequence of an increase of the quasi-classical free energy barrier and to a minor extent of an increased number of recrossing trajectories on the transition state dividing surface. Since the variant enzyme is less well set up to catalyze the reaction, a higher degree of active site reorganization is needed to reach the TS. Although millisecond active site motions are lost in the variant, there is greater flexibility on the femtosecond time scale. The “dynamic knockout” EcDHFR-N23PP/S148A is therefore a “dynamic knock-in” at the level of the chemical step, and the increased dynamic coupling to the chemical coordinate is in fact detrimental to catalysis. This finding is most likely applicable not just to hydrogen transfer in EcDHFR but also to other enzymatic systems. PMID:24252106

  3. 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.

  4. 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

  5. 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

  6. 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

  7. Effect of low-level laser therapy on repair of the bone compromised by radiotherapy.

    PubMed

    Batista, Jonas D; Zanetta-Barbosa, Darceny; Cardoso, Sérgio V; Dechichi, Paula; Rocha, Flaviana S; Pagnoncelli, Rogério M

    2014-11-01

    Radiotherapy (RDT) is commonly used for cancer treatment, but high doses of ionizing radiation can directly affect healthy tissues. Positive biological effects of low-level laser therapy (LLLT) on bone repair have been demonstrated; however, this effect on surgical defects of bone previously compromised by radiotherapy has not been evaluated. The aim of this study was to investigate the influence of LLLT (λ = 830 nm) in femur repair after ionizing radiation. Twenty Wistar rats were divided into four groups: control group (GC, n = 5) creation of bone defects (BDs) only; laser group (GL), with BD and LLLT (n = 5); radiotherapy group (GR), submitted to RDT and BD (n = 5); and radiotherapy and laser group (GRL), submitted to RDT, BD, and LLLT (n = 5). GL and GRL received punctual laser application (DE = 210 J/cm(2), P = 50 mW, t = 120 s, and beam diameter of 0.04 cm(2)) immediately after surgery, with 48-h interval during 7 days. Animals were euthanized at 7 days after surgery, and bone sections were evaluated morphometrically with conventional microscopy. Bone repair was only observed in nonirradiated bone, with significant improvement in GL in comparison to GC. GR and GRL did not present any bone neoformation. The result demonstrated a positive local biostimulative effect of LLLT in normal bone. However, LLLT was not able to revert the bone metabolic damage due to ionizing radiation.

  8. 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

  9. 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

  10. '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.

  11. Compromised Osseous Healing of Dental Extraction Sites in Zoledronic Acid-Treated Dogs

    PubMed Central

    Allen, Matthew R.; Kubek, Daniel J.; Burr, David B.; Ruggiero, Salvatore L.; Chu, Tien-Min Gabriel

    2010-01-01

    PURPOSE The goal of this study was to document how treatment with a bisphosphonate affects the bone tissue following dental extraction. METHODS Skeletally mature female beagle dogs were either untreated controls (CON) or treated with intravenous zoledronic acid (ZOL). Following the extraction of the 4th premolars, healing was allowed for 4 or 8 weeks. Properties of the extraction site were assessed using micro-computed tomography (micro-CT) and dynamic histomorphometry. RESULTS The initial infilling of the extraction socket with bone was not affected by ZOL but subsequent removal of this bone was significantly suppressed compared to CON. After 8-weeks of healing, the alveolar cortical bone adjacent to the extraction socket had a remodeling rate of ~50%/year in CON animals while ZOL-treated animals had a rate of < 1%/year. One ZOL-treated animal developed exposed bone post-extraction which eventually led to the formation of a sequestrum. Assessment of the sequestrum with micro-CT and histology showed that it had features consistent with those reported in humans with osteonecrosis of the jaw. CONCLUSIONS These results, showing significantly compromised post-extraction osseous healing as well as presence of exposed bone and development of a sequestrum in one ZOL animal, provide a building block toward understanding the pathophysiology of osteonecrosis of the jaw. PMID:20458574

  12. Field stimulation of the carotid baroreceptor complex does not compromise baroreceptor function in spontaneously hypertensive rats.

    PubMed

    Kouchaki, Zahra; Georgakopoulos, Dimitrios; Butlin, Mark; Avolio, Alberto P

    2014-01-01

    Field stimulation of the carotid baroreceptors has been successfully used to induce a long-term reduction in blood pressure. However, baroreceptor stimulation may interfere with or compromise the beneficial short-term blood pressure regulation function of the baroreceptors. This study aims to quantify the baroreceptor function before and during acute, unilateral field stimulation of the carotid baroreceptors. Spontaneously Hypertensive Rats (n=7) were anaesthetised and instrumented to measure heart rate and mean arterial pressure (MAP), aortic pulse wave velocity (a surrogate measure of arterial stiffness), abdominal aortic flow and renal artery flow. A custom made field stimulation device was fitted to the left common carotid artery. Baroreceptor function was measured by quantifying heart rate response to MAP change induced by bolus injection of phenylephrine. Field stimulation of the baroreceptors reduced heart rate by 20 bpm (p=0.003) with MAP reduction of 18 mmHg (p=0.008). Maximal barorecep-tor gain without stimulation was -1.20±0.41 bpm/mmHg and during stimulation -1.41±0.52 bpm/mmHg (p=0.59). The MAP at which maximal gain occurred also did not change (152±11, 160±9 mmHg respectively, p=0.22). This study indicates that unilateral field stimulation of the carotid baroreceptor complex, while causing a sustained reduction of arterial pressure, does not alter acute baroreceptor function peak gain. PMID:25570608

  13. ["Need-driven-dementia-compromised-behavior" model and "gentle care" as answer to Alzheimer's disease].

    PubMed

    Gallese, Giulia; Stobbione, Tiziana

    2013-01-01

    Alzheimer's disease is characterized by a progressive cognitive, behavioural and functional decline which determines ability loss. With the gradual aging of the population, Alzheimer's disease is becoming a major health and social problem which involves not only the individuals but also their whole family. The aim of this study is to identify the most important needs of patients and to suggest interventions to manage it at home, according to the pattern of Gentle Care. Care needs of Alzheimer's disease patients have been investigated, through the use of semi-structured interview of caregivers who take care of loved ones at home. The survey has been carried out through the use of a data collection tool proposed in the conceptual model of nursing "Need-driven Dementia-compromised Behaviour Model", validated and tested in the United States. Data highlights an high degree of patient dependence from their caregiver for numerous activities of daily living. Interviews show a poor level of information and lack of support from professionals who can help caregivers in their everyday life. On the basis of the data gathered, a number of care interventions, which seams as the most appropriate in order to best take care of patients, were identified. Moreover, main needs of family caregivers were also identified, they need more information and support with respect to caregiving responsibilities.

  14. Diuretics Prevent Thiazolidinedione-Induced Cardiac Hypertrophy without Compromising Insulin-Sensitizing Effects in Mice

    PubMed Central

    Chang, Cherng-Shyang; Tsai, Pei-Jane; Sung, Junne-Ming; Chen, Ju-Yi; Ho, Li-Chun; Pandya, Kumar; Maeda, Nobuyo; Tsai, Yau-Sheng

    2015-01-01

    Much concern has arisen regarding critical adverse effects of thiazolidinediones (TZDs), including rosiglitazone and pioglitazone, on cardiac tissue. Although TZD-induced cardiac hypertrophy (CH) has been attributed to an increase in plasma volume or a change in cardiac nutrient preference, causative roles have not been established. To test the hypothesis that volume expansion directly mediates rosiglitazone-induced CH, mice were fed a high-fat diet with rosiglitazone, and cardiac and metabolic consequences were examined. Rosiglitazone treatment induced volume expansion and CH in wild-type and PPARγ heterozygous knockout (Pparg+/−) mice, but not in mice defective for ligand binding (PpargP465L/+). Cotreatment with the diuretic furosemide in wild-type mice attenuated rosiglitazone-induced CH, hypertrophic gene reprogramming, cardiomyocyte apoptosis, hypertrophy-related signal activation, and left ventricular dysfunction. Similar changes were observed in mice treated with pioglitazone. The diuretics spironolactone and trichlormethiazide, but not amiloride, attenuated rosiglitazone effects on volume expansion and CH. Interestingly, expression of glucose and lipid metabolism genes in the heart was altered by rosiglitazone, but these changes were not attenuated by furosemide cotreatment. Importantly, rosiglitazone-mediated whole-body metabolic improvements were not affected by furosemide cotreatment. We conclude that releasing plasma volume reduces adverse effects of TZD-induced volume expansion and cardiac events without compromising TZD actions in metabolic switch in the heart and whole-body insulin sensitivity. PMID:24287404

  15. Reproductive investment compromises maternal health in three species of freshwater turtle.

    PubMed

    Rafferty, Anthony R; Scheelings, T Franciscus; Foley, Laura J; Johnstone, Christopher P; Reina, Richard D

    2014-01-01

    Life-history theory predicts that a trade-off in the allocation of resources between different physiological systems exists because resources are finite. As a result, females investing heavily in reproduction may compromise their future health. We used hematology, serum biochemistry, mass, and morphometric measurements as indicators of physiological health state to investigate whether reproductive investment altered subsequent maternal health in three Australian freshwater turtles: the oblong turtle (Chelodina oblonga; n = 12), the Macquarie turtle (Emydura macquarii; n = 9), and the eastern long-necked turtle (Chelodina longicollis; n = 8). Maternal health was impaired in turtles that produced larger and heavier eggs and clutches. In C. oblonga and E. macquarii, increased reproductive investment generally resulted in negative changes to the hematology and serum biochemistry profile of maternal blood. Generally, increases in heterophil/lymphocyte ratio, aspartate transaminase, creatine kinase, calcium/phosphorus ratio, and albumin/globulin ratio were observed following reproduction, in addition to a decrease in glucose and total protein. These findings agree with the physiological constraint hypothesis and highlight the connection between life-history evolution and animal physiology by documenting, for the first time, how measures of physiological health state relate to reproductive investment in Australian freshwater turtles. Additionally, our findings suggest that body condition, a readily used morphological biomarker, is a poor predictor of health in turtles. Our results emphasize the need to investigate how maternal health is influenced by the reproductive process in different species. PMID:24769705

  16. 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.

  17. 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

  18. Extracapsular dissection for clinically benign parotid lumps: reduced morbidity without oncological compromise.

    PubMed

    McGurk, M; Thomas, B L; Renehan, A G

    2003-11-01

    Previous studies have shown that extracapsular dissection (ECD) is an alternative approach to superficial parotidectomy (SP) for pleomorphic adenoma parotid tumours, associated with low recurrence rates equal to those following SP, but with significantly reduced morbidity. However, if a malignant tumour masquerades as a clinically benign lump, this approach may be inappropriate. This study addressed this question by analysing the outcome of 821 consecutive patients with parotid tumours treated at one centre over 40 years and with a median 12 (range 5-30) years follow-up. Tumours were classified as 'simple' (discrete, mobile, < 4 cm: n=662) and 'complex' (deep, fixed, facial nerve palsy, > or =4 cm: n=159). Among the 'simple' or clinically benign tumours, 503 patients underwent ECD; 159 patients underwent SP. In all, 32 (5%) clinically benign cases were subsequently revealed as malignant histologies (ECD, 12; SP, 20). For each group, 5- and 10-year cancer-specific survival rates were 100 and 98%, respectively. There were no differences in recurrence rates when subanalysed by surgical groups, but ECD was associated with significantly reduced morbidity (P < 0.001). This study demonstrates that ECD is a viable alternative to superficial parotidectomy for the majority of parotid tumours, associated with reduced morbidity without oncological compromise.

  19. Is a compromised interferon response an etiologic factor in Reye's syndrome?

    PubMed

    Rozee, K R; Lee, S H; Crocker, J F; Digout, S; Arcinue, E

    1982-04-01

    Young mice injected with sublethal doses of Toximul MP8, a typical commercial polyoxyethylene ether-based emulsifier, died more frequently when infected with encephalomyocarditis virus than did control mice. Lymphocytes taken from emulsifier-injected mice responded poorly to interferon induction, unlike lymphocytes from control animals. Interferon protected control mice against viral encephalomyocarditis, but such protection was not equally demonstrable in emulsifier-injected mice. These data suggest that the enhanced lethality of encephalomyocarditis virus in emulsifier-injected mice is associated with and perhaps caused by a compromised interferon response in these animals. Since these emulsifiers are commonly found in the environment in areas where forests are sprayed with pesticides, a group of children suffering from Reye's syndrome who lived in such areas was investigated. Blood samples were obtained from five children with influenza B-associated Reye's syndrome during their acute illness and during convalescence. Lymphocytes obtained from these samples and from peripheral blood samples from healthy children (controls) were induced to synthesize interferon by exposure to Newcastle disease virus. The lymphocytes from the convalescent patients and from the controls responded well to induction. However, the lymphocytes obtained from patients and from the controls responded well to induction. However, the lymphocytes obtained from patients during the acute phase of Reye's syndrome responded very poorly and produced significantly less interferon.

  20. 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.…

  1. 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…

  2. 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...

  3. The Women's Army Auxiliary Corps: A Compromise to Overcome the Conflict of Women Serving in the Army

    ERIC Educational Resources Information Center

    Permeswaran, Yashila

    2008-01-01

    Though people now take the idea of women in the military for granted, in the 1940s it was a vigorously debated suggestion. Men protected their country; women stayed at home. Because of the conflict over whether women should serve in the army, Congress compromised by creating the Women's Army Auxiliary Corps (WAAC). This article describes the…

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. Removable partial denture design using milled abutment surfaces and minimal soft tissue coverage for periodontally compromised teeth: a clinical report.

    PubMed

    Chaiyabutr, Yada; Brudvik, James S

    2008-04-01

    This clinical report describes the treatment of a partially edentulous patient with periodontally compromised teeth using a combination of single crowns and a removable partial denture (RPD). The RPD was designed to combine the benefits of milled surfaces and hygienic principles while allowing modification and addition of artificial teeth, should natural teeth be lost.

  9. 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)…

  10. 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…

  11. 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...

  12. 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

  13. Malarial dihydrofolate reductase as a paradigm for drug development against a resistance-compromised target

    PubMed Central

    Yuthavong, Yongyuth; Tarnchompoo, Bongkoch; Vilaivan, Tirayut; Chitnumsub, Penchit; Kamchonwongpaisan, Sumalee; Charman, Susan A.; McLennan, Danielle N.; White, Karen L.; Vivas, Livia; Bongard, Emily; Thongphanchang, Chawanee; Taweechai, Supannee; Vanichtanankul, Jarunee; Rattanajak, Roonglawan; Arwon, Uthai; Fantauzzi, Pascal; Yuvaniyama, Jirundon; Charman, William N.; Matthews, David

    2012-01-01

    Malarial dihydrofolate reductase (DHFR) is the target of antifolate antimalarial drugs such as pyrimethamine and cycloguanil, the clinical efficacy of which have been compromised by resistance arising through mutations at various sites on the enzyme. Here, we describe the use of cocrystal structures with inhibitors and substrates, along with efficacy and pharmacokinetic profiling for the design, characterization, and preclinical development of a selective, highly efficacious, and orally available antimalarial drug candidate that potently inhibits both wild-type and clinically relevant mutated forms of Plasmodium falciparum (Pf) DHFR. Important structural characteristics of P218 include pyrimidine side-chain flexibility and a carboxylate group that makes charge-mediated hydrogen bonds with conserved Arg122 (PfDHFR-TS amino acid numbering). An analogous interaction of P218 with human DHFR is disfavored because of three species-dependent amino acid substitutions in the vicinity of the conserved Arg. Thus, P218 binds to the active site of PfDHFR in a substantially different fashion from the human enzyme, which is the basis for its high selectivity. Unlike pyrimethamine, P218 binds both wild-type and mutant PfDHFR in a slow-on/slow-off tight-binding mode, which prolongs the target residence time. P218, when bound to PfDHFR-TS, resides almost entirely within the envelope mapped out by the dihydrofolate substrate, which may make it less susceptible to resistance mutations. The high in vivo efficacy in a SCID mouse model of P. falciparum malaria, good oral bioavailability, favorable enzyme selectivity, and good safety characteristics of P218 make it a potential candidate for further development. PMID:23035243

  14. 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

  15. Bedouin in Lebanon: Social discrimination, political exclusion, and compromised health care.

    PubMed

    Chatty, Dawn; Mansour, Nisrine; Yassin, Nasser

    2013-04-01

    Global inequalities in health have long been associated with disparities between rich and poor nations. The middle-income countries of the Levant (Lebanon, Syria and Jordan) have developed models of health care delivery that mirror the often complex make-up of their states. In Lebanon, which is characterized by political clientelism and sectarian structures, access to health care is more contingent on ethnicity and religious affiliation than on poverty. This case study of the Bedouin of the Middle Bekaa Valley of Lebanon is based on interviews with policymakers, health care providers and the Bedouin as part of a study funded by the European Commission between 2006 and 2010. The study explores the importance of considering social discrimination and political exclusion in understanding compromised health care. Three decades after the Declaration of Alma Ata (1978), which declared that an acceptable level of health care for all should be attained by the year 2000, the Bedouin community of Lebanon remains largely invisible to the government and, thus, invisible to national health care policy and practice. They experience significant social discrimination from health practitioners and policymakers alike. Their unfair treatment under the health system is generally disassociated from issues of wealth or poverty; it is manifested in issues of access and use, discrimination, and resistance and agency. Overcoming their political exclusion and recognizing the social discrimination they face are steps that can be taken to protect and promote equal access to basic reproductive and child health care. This case study of the Bedouin in Lebanon is also relevant to the health needs of other marginalized populations in remote and rural areas.

  16. Pulmonary transcriptional response to ozone in healthy and cardiovascular compromised rat models.

    PubMed

    Ward, William O; Kodavanti, Urmila P

    2015-01-01

    The genetic cardiovascular disease (CVD) and associated metabolic impairments can influence the lung injury from inhaled pollutants. We hypothesized that comparative assessment of global pulmonary expression profile of healthy and CVD-prone rat models will provide mechanistic insights into susceptibility differences to ozone. The lung expression profiles of healthy Wistar Kyoto (WKY) and CVD-compromised spontaneously hypertensive (SH), stroke-prone SH (SHSP), obese SH heart failure (SHHF) and obese, atherosclerosis-prone JCR rats were analyzed using Affymetrix platform immediately after 4-h air or 1 ppm ozone exposure. At baseline, the JCR exhibited the largest difference in the number of genes among all strains when compared with WKY. Interestingly, the number of genes affected by ozone was inversely correlated with genes different at baseline relative to WKY. A cluster of NFkB target genes involved in cell-adhesion, antioxidant response, inflammation and apoptosis was induced in all strains, albeit at different levels (JCR < WKY < SHHF < SH < SHSP). The lung metabolic syndrome gene cluster indicated expressions in opposite directions for SHHF and JCR suggesting different mechanisms for common disease phenotype and perhaps obesity-independent contribution to exacerbated lung disease. The differences in expression of adrenergic receptors and ion-channel genes suggested distinct mechanisms by which ozone might induce protein leakage in CVD models, especially SHHF and JCR. Thus, the pulmonary response to ozone in CVD strains was likely linked to the defining gene expression profiles. Differential transcriptional patterns between healthy and CVD rat strains at baseline, and after ozone suggests that lung inflammation and injury might be influenced by multiple biological pathways affecting inflammation gene signatures.

  17. 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

  18. 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.

  19. Temephos Resistance in Aedes aegypti in Colombia Compromises Dengue Vector Control

    PubMed Central

    Grisales, Nelson; Poupardin, Rodolphe; Gomez, Santiago; Fonseca-Gonzalez, Idalyd; Ranson, Hilary; Lenhart, Audrey

    2013-01-01

    Background Control and prevention of dengue relies heavily on the application of insecticides to control dengue vector mosquitoes. In Colombia, application of the larvicide temephos to the aquatic breeding sites of Aedes aegypti is a key part of the dengue control strategy. Resistance to temephos was recently detected in the dengue-endemic city of Cucuta, leading to questions about its efficacy as a control tool. Here, we characterize the underlying mechanisms and estimate the operational impact of this resistance. Methodology/Principal Findings Larval bioassays of Ae. aegypti larvae from Cucuta determined the temephos LC50 to be 0.066 ppm (95% CI 0.06–0.074), approximately 15× higher than the value obtained from a susceptible laboratory colony. The efficacy of the field dose of temephos at killing this resistant Cucuta population was greatly reduced, with mortality rates <80% two weeks after application and <50% after 4 weeks. Neither biochemical assays nor partial sequencing of the ace-1 gene implicated target site resistance as the primary resistance mechanism. Synergism assays and microarray analysis suggested that metabolic mechanisms were most likely responsible for the temephos resistance. Interestingly, although the greatest synergism was observed with the carboxylesterase inhibitor, DEF, the primary candidate genes from the microarray analysis, and confirmed by quantitative PCR, were cytochrome P450 oxidases, notably CYP6N12, CYP6F3 and CYP6M11. Conclusions/Significance In Colombia, resistance to temephos in Ae. aegypti compromises the duration of its effect as a vector control tool. Several candidate genes potentially responsible for metabolic resistance to temephos were identified. Given the limited number of insecticides that are approved for vector control, future chemical-based control strategies should take into account the mechanisms underlying the resistance to discern which insecticides would likely lead to the greatest control efficacy while

  20. Environmentally persistent free radicals compromise left ventricular function during ischemia/reperfusion injury

    PubMed Central

    Burn, Brendan R.

    2015-01-01

    Increases in airborne particulate matter (PM) are linked to increased mortality from myocardial ischemia. PM contains environmentally persistent free radicals (EPFRs) that form as halogenated hydrocarbons chemisorb to transition metal oxide-coated particles, and are capable of sustained redox cycling. We hypothesized that exposure to the EPFR DCB230 would increase cardiac vulnerability to subsequent myocardial ischemia-reperfusion (MI/R) injury. Rats were exposed to DCB230 or vehicle via nose-only inhalation (230 μg max/day) over 30 min/day for 7 days. MI/R or sham MI/R (sham) was initiated 24 h after the final exposure. Following 1 or 7 days of reperfusion, left ventricular (LV) function was assessed and infarct size measured. In vehicle-exposed rats, MI/R injury did not significantly reduce cardiac output (CO), stroke volume (SV), stroke work (SW), end-diastolic volume (EDV), or end-systolic volume (ESV) after 1 day of reperfusion, despite significant reductions in end-systolic pressure (ESP). Preload-recruitable SW (PRSW; contractility) was elevated, presumably to maintain LV function. MI/R 1-day rats exposed to DCB230 also had similarly reduced ESP. Compared with vehicle controls, CO, SV, and SW were significantly reduced in DCB230-exposed MI/R 1-day rats; moreover, PRSW did not increase. DCB230’s effects on LV function dissipated within 8 days of exposure. These data show that inhalation of EPFRs can exacerbate the deficits in LV function produced by subsequent MI/R injury. Infarct size was not different between the MI/R groups. We conclude that inhalation of EPFRs can compromise cardiac function during MI/R injury and may help to explain the link between PM and MI/R-related mortality. PMID:25681431

  1. Genetic identification of missing persons: DNA analysis of human remains and compromised samples.

    PubMed

    Alvarez-Cubero, M J; Saiz, M; Martinez-Gonzalez, L J; Alvarez, J C; Eisenberg, A J; Budowle, B; Lorente, J A

    2012-01-01

    Human identification has made great strides over the past 2 decades due to the advent of DNA typing. Forensic DNA typing provides genetic data from a variety of materials and individuals, and is applied to many important issues that confront society. Part of the success of DNA typing is the generation of DNA databases to help identify missing persons and to develop investigative leads to assist law enforcement. DNA databases house DNA profiles from convicted felons (and in some jurisdictions arrestees), forensic evidence, human remains, and direct and family reference samples of missing persons. These databases are essential tools, which are becoming quite large (for example the US Database contains 10 million profiles). The scientific, governmental and private communities continue to work together to standardize genetic markers for more effective worldwide data sharing, to develop and validate robust DNA typing kits that contain the reagents necessary to type core identity genetic markers, to develop technologies that facilitate a number of analytical processes and to develop policies to make human identity testing more effective. Indeed, DNA typing is integral to resolving a number of serious criminal and civil concerns, such as solving missing person cases and identifying victims of mass disasters and children who may have been victims of human trafficking, and provides information for historical studies. As more refined capabilities are still required, novel approaches are being sought, such as genetic testing by next-generation sequencing, mass spectrometry, chip arrays and pyrosequencing. Single nucleotide polymorphisms offer the potential to analyze severely compromised biological samples, to determine the facial phenotype of decomposed human remains and to predict the bioancestry of individuals, a new focus in analyzing this type of markers.

  2. 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

  3. 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

  4. Proteasome Dysfunction Associated to Oxidative Stress and Proteotoxicity in Adipocytes Compromises Insulin Sensitivity in Human Obesity

    PubMed Central

    Díaz-Ruiz, Alberto; Guzmán-Ruiz, Rocío; Moreno, Natalia R.; García-Rios, Antonio; Delgado-Casado, Nieves; Membrives, Antonio; Túnez, Isaac; El Bekay, Rajaa; Fernández-Real, José M.; Tovar, Sulay; Diéguez, Carlos; Tinahones, Francisco J.; Vázquez-Martínez, Rafael; López-Miranda, José

    2015-01-01

    Abstract Aims: Obesity is characterized by a low-grade systemic inflammatory state and adipose tissue (AT) dysfunction, which predispose individuals to the development of insulin resistance (IR) and metabolic disease. However, a subset of obese individuals, referred to as metabolically healthy obese (MHO) individuals, are protected from obesity-associated metabolic abnormalities. Here, we aim at identifying molecular factors and pathways in adipocytes that are responsible for the progression from the insulin-sensitive to the insulin-resistant, metabolically unhealthy obese (MUHO) phenotype. Results: Proteomic analysis of paired samples of adipocytes from subcutaneous (SC) and omental (OM) human AT revealed that both types of cells are altered in the MUHO state. Specifically, the glutathione redox cycle and other antioxidant defense systems as well as the protein-folding machinery were dysregulated and endoplasmic reticulum stress was increased in adipocytes from IR subjects. Moreover, proteasome activity was also compromised in adipocytes of MUHO individuals, which was associated with enhanced accumulation of oxidized and ubiquitinated proteins in these cells. Proteasome activity was also impaired in adipocytes of diet-induced obese mice and in 3T3-L1 adipocytes exposed to palmitate. In line with these data, proteasome inhibition significantly impaired insulin signaling in 3T3-L1 adipocytes. Innovation: This study provides the first evidence of the occurrence of protein homeostasis deregulation in adipocytes in human obesity, which, together with oxidative damage, interferes with insulin signaling in these cells. Conclusion: Our results suggest that proteasomal dysfunction and impaired proteostasis in adipocytes, resulting from protein oxidation and/or misfolding, constitute major pathogenic mechanisms in the development of IR in obesity. Antioxid. Redox Signal. 23, 597–612. PMID:25714483

  5. GGGGCC repeat expansion in C9ORF72 compromises nucleocytoplasmic transport

    PubMed Central

    Freibaum, Brian D.; Lu, Yubing; Lopez-Gonzalez, Rodrigo; Kim, Nam Chul; Almeida, Sandra; Lee, Kyung-Ha; Badders, Nisha; Valentine, Marc; Miller, Bruce L.; Wong, Philip C.; Petrucelli, Leonard; Kim, Hong Joo; Gao, Fen-Biao; Taylor, J. Paul

    2015-01-01

    GGGGCC (G4C2) repeat expansion in a noncoding region of C9ORF72 is the most common cause of sporadic and familial forms of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD)1,2. The basis for pathogenesis is unknown. To capture the consequences of G4C2 repeat expansion in a tractable genetic system, we generated transgenic fly lines expressing 8, 28 or 58 G4C2 repeat-containing transcripts that do not have a translation start site (AUG) but contain an open-reading frame for green fluorescent protein (GFP) to detect repeat-associated non-AUG (RAN) translation. These transgenic animals show dosage-dependent, repeat length-dependent degeneration in neuronal tissues and RAN translation of dipeptide repeat (DPR) proteins as observed in patients. This model was used in a large-scale, unbiased genetic screen ultimately leading to the identification of 18 genetic modifiers that encode components of the nuclear pore complex (NPC) as well as the machinery that coordinates the export of nuclear RNA and the import of nuclear proteins. Consistent with these results we found morphological abnormalities in the architecture of the nuclear envelope in cells expressing expanded G4C2 repeats in vitro and in vivo. Moreover, we identified a substantial defect in RNA export resulting in retention of RNA in the nuclei of Drosophila cells expressing expanded G4C2 repeats and also in mammalian cells, including aged iPSC-derived neurons from C9ORF72 patients. These studies show that a primary consequence of G4C2 repeat expansion is the compromise of nucleocytoplasmic transport through the nuclear pore, revealing a novel mechanism of neurodegeneration. PMID:26308899

  6. 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

  7. 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

  8. 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

  9. Host lung immunity is severely compromised during tropical pulmonary eosinophilia: role of lung eosinophils and macrophages.

    PubMed

    Sharma, Pankaj; Sharma, Aditi; Vishwakarma, Achchhe Lal; Agnihotri, Promod Kumar; Sharma, Sharad; Srivastava, Mrigank

    2016-04-01

    Eosinophils play a central role in the pathogenesis of tropical pulmonary eosinophilia, a rare, but fatal, manifestation of filariasis. However, no exhaustive study has been done to identify the genes and proteins of eosinophils involved in the pathogenesis of tropical pulmonary eosinophilia. In the present study, we established a mouse model of tropical pulmonary eosinophilia that mimicked filarial manifestations of human tropical pulmonary eosinophilia pathogenesis and used flow cytometry-assisted cell sorting and real-time RT-PCR to study the gene expression profile of flow-sorted, lung eosinophils and lung macrophages during tropical pulmonary eosinophilia pathogenesis. Our results show that tropical pulmonary eosinophilia mice exhibited increased levels of IL-4, IL-5, CCL5, and CCL11 in the bronchoalveolar lavage fluid and lung parenchyma along with elevated titers of IgE and IgG subtypes in the serum. Alveolar macrophages from tropical pulmonary eosinophilia mice displayed decreased phagocytosis, attenuated nitric oxide production, and reduced T-cell proliferation capacity, and FACS-sorted lung eosinophils from tropical pulmonary eosinophilia mice upregulated transcript levels of ficolin A and anti-apoptotic gene Bcl2,but proapoptotic genes Bim and Bax were downregulated. Similarly, flow-sorted lung macrophages upregulated transcript levels of TLR-2, TLR-6, arginase-1, Ym-1, and FIZZ-1 but downregulated nitric oxide synthase-2 levels, signifying their alternative activation. Taken together, we show that the pathogenesis of tropical pulmonary eosinophilia is marked by functional impairment of alveolar macrophages, alternative activation of lung macrophages, and upregulation of anti-apoptotic genes by eosinophils. These events combine together to cause severe lung inflammation and compromised lung immunity. Therapeutic interventions that can boost host immune response in the lungs might thus provide relief to patients with tropical pulmonary eosinophilia. PMID

  10. Ocean acidification compromises recruitment success of the threatened Caribbean coral Acropora palmata.

    PubMed

    Albright, Rebecca; Mason, Benjamin; Miller, Margaret; Langdon, Chris

    2010-11-23

    Ocean acidification (OA) refers to the ongoing decline in oceanic pH resulting from the uptake of atmospheric CO(2). Mounting experimental evidence suggests that OA will have negative consequences for a variety of marine organisms. Whereas the effect of OA on the calcification of adult reef corals is increasingly well documented, effects on early life history stages are largely unknown. Coral recruitment, which necessitates successful fertilization, larval settlement, and postsettlement growth and survivorship, is critical to the persistence and resilience of coral reefs. To determine whether OA threatens successful sexual recruitment of reef-building corals, we tested fertilization, settlement, and postsettlement growth of Acropora palmata at pCO(2) levels that represent average ambient conditions during coral spawning (∼400 μatm) and the range of pCO(2) increases that are expected to occur in this century [∼560 μatm (mid-CO(2)) and ∼800 μatm (high-CO(2))]. Fertilization, settlement, and growth were all negatively impacted by increasing pCO(2), and impairment of fertilization was exacerbated at lower sperm concentrations. The cumulative impact of OA on fertilization and settlement success is an estimated 52% and 73% reduction in the number of larval settlers on the reef under pCO(2) conditions projected for the middle and the end of this century, respectively. Additional declines of 39% (mid-CO(2)) and 50% (high-CO(2)) were observed in postsettlement linear extension rates relative to controls. These results suggest that OA has the potential to impact multiple, sequential early life history stages, thereby severely compromising sexual recruitment and the ability of coral reefs to recover from disturbance.

  11. 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

  12. Bisphenol A reduces fertilizing ability and motility by compromising mitochondrial function of sperm.

    PubMed

    Singh, Ram P; Shafeeque, Chathathayil M; Sharma, Sanjeev K; Pandey, Nitin K; Singh, Renu; Mohan, Jag; Kolluri, Gautham; Saxena, Meeta; Sharma, Bhaskar; Sastry, Kochiganti V H; Kataria, Jag M; Azeez, Parappurath A

    2015-07-01

    Bisphenol A (BPA) acts as an endocrine disruptor, affects animal reproductive success in vivo and affects sperm functions in vitro at environmentally relevant concentrations, leading to reduction in sperm motility and fertilizing ability in fish. The effect of in vitro BPA on avian sperm functions has not been explored. The present study examined the effect of environmentally relevant concentrations of BPA (0 mM, 0.18 mM, 0.37 mM, and 0.74 mM) on sperm functions in chicken in vitro. Sperm were exposed to concentrations of BPA for 30 min and analyzed for motility, fertilizing ability, live sperm percentage, and mitochondrial membrane potential (Δψm). Results showed that BPA at a concentration of 0.74 mM significantly decreased motility, fertilizing ability, live sperm count percentage, and sperm Δψm. Sperm motility was positively correlated with fertility (r = 0.73, p ≤ 0.01), live sperm percentage (r = 0.64, p ≤ 0.01), and high Δψm (r = 0.44, p ≤ 0.01). A dose-dependent and time-dependent effect of BPA was observed on sperm motility at all BPA concentrations. However, sperm's fertilizing ability was unaffected in low BPA concentration (0.18 mM and 0.37 mM). A significantly higher percentage of moribund sperm was observed at 0.37 mM and 0.74 mM BPA compared with at 0.18 mM BPA, in the negative control, and in the vehicle control. The present study confirms that environmentally relevant concentrations of BPA are capable of compromising sperm functions, leading to reduction in fertilizing ability of chicken sperm.

  13. 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

  14. 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

  15. Sleep quantity and quality is not compromised during planned burn shifts of less than 12 h.

    PubMed

    Vincent, Grace E; Aisbett, Brad; Hall, Sarah J; Ferguson, Sally A

    2016-01-01

    Planned burning is a preventative strategy aimed at decreasing fuel loads to reduce the severity of future wildfire events. During planned burn operations, firefighters can work long shifts. Furthermore, remote burning locations may require firefighters to sleep away from home between shifts. The existing evidence surrounding firefighters' sleep during such operations is exclusively anecdotal. The aims of the study were to describe firefighters' sleep during planned burn operations and evaluate the impact of the key operational factors (shift start time, shift length and sleeping location) that may contribute to inadequate sleep. Thirty-three salaried firefighters were recruited from Australia's fire agencies and sleep was measured objectively using wrist actigraphy for four weeks. All variables were examined in two conditions: (1) burn days, and (2) non-burn days. Time in bed, total sleep time, sleep latency and sleep efficiency were evaluated objectively. Subjective reports of pre- and post-sleep fatigue, sleep location, sleep quality, sleep quantity, number of times woken and sleep timing were also recorded. Analyses revealed no differences in measures of sleep quantity and quality when comparing non-burn and burn days. Total sleep time was less when planned burn shifts were >12 h. However, on burn days, work shift start time as well as sleeping location did not impact firefighters' sleep quantity. Self-reported levels of pre- and post-sleep fatigue were greater on burn days compared to non-burn days. These findings indicate that sleep quantity and quality are not compromised during planned burn operations <12 h in duration.

  16. 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

  17. 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

  18. The up and down bobbing of human walking: a compromise between muscle work and efficiency.

    PubMed

    Massaad, Firas; Lejeune, Thierry M; Detrembleur, Christine

    2007-07-15

    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.

  19. 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

  20. Interaction with amyloid beta peptide compromises the lipid binding function of apolipoprotein E.

    PubMed

    Tamamizu-Kato, Shiori; Cohen, Jenny K; Drake, Carolyn B; Kosaraju, Malathi G; Drury, Jessica; Narayanaswami, Vasanthy

    2008-05-01

    Apolipoprotein (apo) E is an exchangeable apolipoprotein that plays an integral role in cholesterol transport in the plasma and the brain. It is also associated with protein misfolding or amyloid proteopathy of the beta amyloid peptide (Abeta) in Alzheimer's disease (AD) and cerebral amyloid angiopathy. The C-terminal domain (CT) of apoE encompasses two types of amphipathic alpha helices: a class A helix (residues 216-266) and a class G* helix (residues 273-299). This domain also harbors high-affinity lipoprotein binding and apoE self-association sites that possibly overlap. The objective of this study is to examine if the neurotoxic oligomeric Abeta interacts with apoE CT and if this association affects the lipoprotein binding function of recombinant human apoE CT. Site-specific fluorescence labeling of single cysteine-containing apoE CT variants with donor probes were employed to identify the binding of Abeta bearing an acceptor probe by intermolecular fluorescence resonance energy-transfer analysis. A higher efficiency of energy transfer was noted with probes located in the class A helix than with those located in the class G* helix of apoE CT. In addition, incubation of apoE CT with Abeta severely impaired the lipid binding ability and the overall amount of lipid-associated apoE CT. However, when apoE CT is present in a lipid-bound state, Abeta appears to be localized within the lipid milieu of the lipoprotein particle and not associated with any specific segments of the protein. When our data are taken together, they suggest that Abeta association compromises the fundamental lipoprotein binding function of apoE, which may have implications not only in terms of amyloid buildup but also in terms of the accumulation of cholesterol at extracellular sites.